IBMS/ECTS 2001 - PROGRAM and ABSTRACTS
POSTER PRESENTATIONS
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Osteoporosis: Pathophysiology
NORMAL VALUES FOR QUANTITATIVE ULTRASONOMETRY AT DIFFERENT SKELETAL SITES (RADIUS, TIBIA) IN HEALTHY CAUCASIAN BOYS AGED 7-19 YEARS – INTERIM ANALYSIS OF 228 BOYS MEASURED
O. Bock1*, M. Berndsen1, T. Biedermann2, A. Oldenburg1, M. Schöntube2, D. Felsenberg1
1Free University Berlin, University Hospital Benjamin Franklin, Osteoporosis Research Group, Berlin, Germany
2Dept.of Rheumatology, 2nd Children's Hospital, Klinikum Buch, Berlin, Germany
Quantitative ultrasound (QUS) is an interesting tool for assessment of bone development in childhood as a fundament for further research to establish effective prevention strategies for osteoporosis in later life and for early diagnosis and treatment control of osteoporosis in children.
Using the Sunlight Omnisense Bone Sonometer (Sunlight Medical Ltd., Rehovot, Israel), we measured 228 healthy Caucasian boys – mean age 12.56 years (SD 2.95; range 7-19 years) – at radius and tibia for an age and sex specific normative data base.
In addition, we compared the data with the results in 335 healthy Caucasian girls (Ref.1).
Intra- and inter-observer variation had been tested before in 15 volunteers - the short-term intra-observer CV was 0.35% and 0.44%, the inter-observer CV was 0.79% and 1.03% at radius and tibia.
Additional information was obtained by questionnaire (regarding calcium intake, physical activity, family history for osteoporosis, diseases interfering with bone metabolism and overall health), height and weight measurements, Tanner staging.
A statistical significant correlation between age and maximum speed of sound (SOS) was found only in boys aged 15 years and older (p<0.001) - radius (r=0.62) and tibia (r=0.54) – whereas in younger boys no significant differences in SOS mean values between age groups have been observed.
Marked and significant increases in the maximum SOS between Tanner stages were found only between Tanner stages IV and V at both measurement sites (p<0.001).
Compared with these data girls of the same age show different age and puberty related changes in their SOS values with a slower but continuous and significant increase in the maximum SOS between Tanner stages II – V at tibia and between Tanner stages III – V at radius.
This is the first study to present normative data for QUS measurements at different sites in Caucasian boys including a comparison to normative data in girls.
Ref.1: Bock O, Luck A, Biedermann T, et al.: Normal Values for Quantitative Ultrasonometry at Different Skeletal Sites (Radius, Tibia, Phalanx) in Caucasian Girls Aged 7-19 Years; Workshop on Bone Mineral Density in Children, Heidelberg (Germany), Dec 1-2, 2000.
EVOLUTION OF GENDER-RELATED DIFFERENCES OF DISTAL RADIUS STRUCTURE IN HUMANS FROM 6 TO 84 YEARS OF AGE: A PQCT STUDY
J. L. Ferretti1*, G. Cointry1, H. Plotkin2, J. R. Zanchetta2
1Rosario University, Argentina
2USAL University, Buenos Aires, Argentina
Menstruating women have more whole-body BMC per unit of lean mass (DXA) than men [Bone 22:693, 1998]. We have analyzed biomechanically these differences by measuring the cross-sectional area (CSA), BMC and volumetric BMD (vBMD) of cortical, cortical-subcortical, and total bone; cortical area moment of inertia (CSMI), and Bone Strength Index (BSI = vBMD x CSMI) in 4%-distal radial pQCT scans (Stratec XCT-960) of 155 males (6-84 y) and 176 females (6-77 y), healthy and otherwise untreated.
Both the periosteal perimeter and the cortical CSA were larger in men than women. The CSMI (reflecting the more or less peripheral distribution of cortical bone) was higher in males than females for the same cortical CSA. The CSMI differed largely between genders but correlated closely with the BSI showing similar slopes for males and females (biomechanical equivalence of male and female skeletons). The hyperbolic relationships between CSMI (y) and vBMD of the total bone (x) ("mass / distribution" curves) showed progressively higher intercepts for prepubertal children (2-12 yr), peripubertal boys / girls (13-15 yr), postpubertal men, and pre- and post-menopausal women. Conversely, the pre-menopausal women showed a higher cortical-subcortical-vBMD / total-BMC ratio than any other group.
Results show that 1. boys and girls have similar bone features, 2. the postpubertal increase in DXA-BMC has a tomographic correlate; 3. the BSI is closely determined by the metaphyseal architecture in both genders; 3. the CSMI is higher in men (larger periosteal perimeter) than in age-matched women, regardless of the vBMD; 4. men show higher BSI values than women if their CSMIis also higher, regardless of the bone mass, and 5) women tend to accumulate bone in the inner side of the cortex (mechanially less effectively than on the other aspect) and close to marrow (a typical estrogen effect). These differences a, tend to compensate biomechanically for the higher accumulation of BMC in menstruating women than men (proposedly convenient for reproduction), and b. point out the wider applicability of tomographic than densitometric data for bone structure / strength estimations.
BONE STRUCTURE OF THE ILIAC CREST AND LUMBAR SPINE: A HISTOMORPHOMETRIC STUDY OF ADULT POPULATION IN CROATIA
O. Cvijanovic*, I. Kristofic, J. Spanjol, S. Zoricic, I. Maric, D. Bobinac
Department of Anatomy, University of Rijeka, Rijeka, Croatia
The aim of this study was to compare vertical 7 mm thick cylinders of vertebral (L3) and iliac trabecular bone (anterior, posterior, lateral) obtained from 40 normal cadavers aged from 40 to 80 years (20 females and 20 males). Undecalcified trabecular bone samples were embedded in MMA, cut in 7 microm thick sections and stained with TB and Goldner trichrome. Histomorphometric analysis was performed on an image analyzer (VAMS, Issa, Zagreb), and the following parameters were determined: Trabecular bone volume (BV/TV), surface density (BS/TV), trabecular thickness (Tb.Th), number (Tb.N) and separation (Tb.Sp), osteoid thickness (O.Th), volume (OV/BV) and surface (OS/BS). Iliac crest and lumbar vertebra bone samples were compared within each group and between different age-related groups. Men and women within the age range 60 to 80 yr had significantly increased O.Th (p<0.001), OV/BV (p<0.005) and OS/BS (p<0.001) in lumbar vertebrae. Moreover, Tb.S (p<0.001) was higher in lumbar bone, while BV/ TV (p<0.001) and Tb.Th (p<0.005) were greater in mens iliac crest. BV/TV (p<0.05), BS/TV (p<0.001), and Tb.N (p<0.001), determined from both lumbar and iliac bone samples, were found significantly increased in a group of younger women (40-60 yr) while Tb.Sp (p<0.005) was lesser, when compared with a group of elderly women. Similarly, in a group of younger men we found BV/TV (p<0.001) and Tb.Th (p<0.005) greater while Tb.Sp (p<0.001) was lesser when compared to elderly men. These results indicate that age-related changes in bone microarchitecture more dramatically affect the vertebrae and less the iliac crest bone. We suggests that increased O.Th, OV/BV, OS/BS vertebral values in elderly women reflect the initial bone repairment, following trabecular microfractures.
COMPUTED-TOMOGRAPHY BONE-DENSITY MEASUREMENTS IN NORMAL PRE- AND POST-PUBERTAL FEMALES
T. N. Hangartner1*, M. E. Miller2
1BioMedical Imaging Laboratory, Wright State University, Dayton OH, USA
2Department of Pediatrics, Wright State University, Dayton, OH, USA
Not much is known about how bone density changes with age during childhood. Standard, two-dimensional methods of bone-density measurement such as dual- energy absorptiometry (DXA) are not well suited to address this issue as their results are size-dependent. We have used the OsteoQuant(r), a peripheral quantitative computed-tomography scanner, to determine the bone density of both the radius and tibia in 13 healthy, prepubertal girls ages 7 and 8 years and 8 healthy, postpubertal girls ages 18 and 19 years. CT bone-density measurements are direct, volumetric determinations of bone density which can quantify cortical bone density (CBD) and trabecular bone density (TBD) separately. The results are shown in the table below.
These results indicate that there is a significant increase in CBD as girls advance through puberty, and by the time they reach age 20, most have realized a density that is approaching normal adult female values (2.0±0.05 g/cm3). However, TBD does not significantly change as girls advance through puberty, and by the time they reach 20, most are still significantly below values of TBD for normal adult females (radius: 0.390±0.075 g/cm3; tibia: 0.45±0.075 g/cm3) There are no significant differences in the CBD of the radius compared to the tibia in either group. However, TBD is significantly greater in the tibia compared to the radius in both groups, an observation that is confirmed by our data for adults as well.
| Group | Radius | Tibia | ||
| CBD | TBD | CBD | TBD | |
| PRE | 1.770±.066 | 0.264±.036 | 1.698±.067 | 0.327±.028 |
| POST | 1.971±.040 | 0.252±.033 | 1.963±.073 | 0.340±.032 |
| Bone density (g/cm3);mean ± 1 standard deviation of pre- and post-pubertal girls | ||||
DEVELOPMENT OF BONE MINERAL DENSITY AT THE SPINE AND HIP IN JAPANESE BOYS AND GIRLS OF THE SAME AGE BUT ON THE DIFFERENT STAGES OF MATURITY
H. Naka1*, M. Iki2, A. Morita2, H. Aihara2, Y. Ikeda2
1Kyoto University of Education, Kyoto, Japan
2Kinki University School of Medicine, Osaka-Sayama, Japan
PURPOSE: The purpose of this study was to clarify the process of development of bone mineral density (BMD) of the spine, femoral neck and total hip in Japanese boys and girls of the same age but on the different stages of maturity.
METHODS: We examined 412 first grade students (133 boys and 279 girls) of 3 junior high schools in Kyoto, Japan. BMD at the lumbar spine, femoral neck and total hip were measured by DXA (QDR4500A, Hologic). Present involvements and past history of illness, lifestyle factors such as diet and exercise habits, and information on maturity were obtained from detailed interviews. The stage of maturity was judged by the age at the first appearance of the pubic hair in boys or by the age at menarche in girls.
RESULT: The girls showed significantly greater BMD than did the boys at the spine, but the total hip BMD was significantly greater in boys. The femoral neck BMD did not differ between boys and girls. The more mature students had the greater BMD at every skeletal sites in both sexes. Height and weight were highly correlated with BMD at every skeletal sites in both sexes regardless of the onset of the maturity.
CONCLUSION: Bone mineral density at the spine, femoral neck and total hip were greatly associated with height, weight and stage of maturity in boys and girls even though their ages were same.
RELATION BETWEEN BONE MASS AT AGE 36 AND CALCIUM INTAKE AND PHYSICAL ACTIVITY DURING THE 25 FOREGOING YEARS
I. Bakker*, H. C. G. Kemper, J. W. R. Twisk, W. van Mechelen
EMGO Institute, Vrije Universiteit, Amsterdam, The Netherlands
In the Amsterdam Growth and Health Longitudinal Study the relation between bone mass at adult age (36 years), and physical activity and calcium intake during the 25 foregoing years was studied. Physical activity (Verschuur, 1987) and nutritional intake (Post, 1989) were monitored 9 respectively 8 times in a group of approximately 450 males and females between age 12 and 36, by cross-check interviews with a reference period of 3 respectively 1 month. Physical activity was analysed in two ways: with respect to the amount of energy expenditure (multiples of the basal metabolic rate, MET) and with respect to the amount of biomechanical ground reaction forces (peak strain, PS). Calcium intake was calculated from the nutritional intake by use of the Dutch "NEVO" table. Bone mass was measured as bone mineral density (BMD) by DXA at the lumbar spine (L2-L4) at age 36.
Multiple linear regression analysis, with gender and body mass included as covariates, was used to analyse the relation between BMD at age 36, and physical activity and calcium intake during 3 foregoing periods: adolescence (ages 13-16), young adulthood (ages 21-29) and adulthood (ages 33-36). In case of interaction (alpha=.10) stratified analysis were performed. Subjects were included into the analyses if they were measured at least once during the analysed period.
The results show the following: MET shows a positive significant (p<.001) relation with lumbar BMD for both sexes during the adolescent period (beta=.21) and for the 50% heaviest males and females (>68 kg) during the young adult period (p=.024, beta=.26). PS shows significant (p<.01) positive relations with lumbar BMD for all age periods but for men only: beta(sub adolescence)=.25, beta(sub young adulthood)=.60 and, for the 50% heaviest adult males (>80 kg), beta(sub adulthood)=.33. No relation was found between calcium intake during the foregoing 3 periods and lumbar BMD at age 36.
It can be concluded that physical activity is of importance during adolescence and (young) adulthood in improving adult bone mineral density and therefore in preventing osteoporosis later in life.
BONE MARKERS PROFILE DURING ADOLESCENT PREGNANCY ON CALCIUM SUPPLEMENTATION
J. A. Prada1*, R. I. Sierra1, R. C. Tsang1, S. Guo2
1Children's Hospital Medical Center, Cincinnati, Ohio, USA
2Wright State University, Dayton, Ohio, USA
The Recommended Daily Allowance of calcium during adolescent pregnancy is 1200 mg/day (US-FNB). There is no recommendation for an increment in calcium intake to meet the presumably greater calcium needs of pregnancy as related to bone metabolism changes. Since there are no studies of bone markers during teenage pregnancy, we enrolled 115 healthy pregnant adolescents into a calcium/ placebo trial of 1000 mg/day. Samples were collected to measure calcium metabolism; total and ionized,(tCa, and iCa) parathyroid hormone(PTH), calcitriol (1,25 (OH)2 vitamin D) and bone metabolism, osteocalcin (OC), procollagen type I (PICP), and carboxyterminal telopeptide of procollagen type I (ICTP) as indices of bone formation and resorption respectively. We hypothesized that calcium supplementation during adolescent pregnancy would increase indices of bone turnover.
By 38 weeks of gestation there were significant differences (by ANOVA) in the concentration of tCa, and 1,25 (OH)2 vitamin D, and in OC, PICP, and ICTP between adolescents on calcium or placebo supplementation. The concentration of tCa of adolescents on calcium supplementation was 9.2±0.4 mg/dL and those on placebo was 8.9±0.4 (P=0.05). The concentration of 1,25 (OH)2 vitamin D of adolescents on calcium supplementation was 101.2±46.1 pg/mL and those on placebo 79.3±38.2 pg/mL, (P=0.05). The concentration of OC was 5.4±1.8 ng/mL and 4.6±1.7 ng/mL (P=0.05), PICP 157.8±36.7 ng/mL and 147.2±36.9 ng/mL (P=0.05), and ICTP; 7.0±1.7 g/L and 5.5±1.4 g/L (P=0.05) for adolescents on calcium and placebo supplementation respectively. The concentration of PTH was reduced in adolescents on calcium supplementation but did not reach significance (18.6±8.2 pg/mL and 15.5±11.5 pg/mL, P=0.06).
Calcium supplementation initiated in the second trimester of adolescent pregnancy increases bone turnover: there are increases in concentrations of OC and PICP, indices of bone formation, and ICTP, an index of bone resorption, in conjunction with increases in 1,25 (OH)2 vitamin D and serum calcium. Conclusion: Calcium supplementation increases bone turnover of pregnant adolescents receiving 1000 mg of calcium per day.
ABSENT BONE MASS IN A CHILD WITH DRUG-REFRACTORY EPILEPTOGENIC ENCEPHALOPATHY
D. Rigante1, P. Ranieri2, G. Segni1, P. Caradonna2*
1Dept. of Pediatrics, UCSC, Rome, Italy
2Dept. of Int. Medicine and Geriatrics, UCSC, Rome, Italy
Bone integrity in children with epilepsy needs to be preserved with monitoring for drug toxicity or disturbed bone metabolism that may contribute to insufficient skeletal strength and massiveness.
We encountered a female child, full-term born, who presented refractory epilepsy with signs of psycho-motor regression since the age of 3 months and sustained globally 10 fractures in the axial bones. Over a 3-year period all anticonvulsant drugs (mostly valproate) had been used with poor benefit. Diagnosis of succinate cytochrome c reductase (complex II of the respiratory chain) deficiency emerged on muscle biopsy at 3 years and 8/12 with mild secondary persistent hyperammonemia. Diet was characterized by medical foods with essential aminoacids, minerals and vitamin D supplemented, anyway hypocalcemia remained unchanged and her weight was 8.55 kg (-4 SD). Dual energy X-ray absorptiometry (DEXA, Hologic QDR 2000) revealed the almost complete absence of bone mineralization: bone mineral density was greatly reduced and readable only at skull, arms, some ribs, few thoracic vetrebra and L4 (here BMD was 0.389). Other blood tests showed: alkaline phosphatase 556 UI/l, 25OH-vitamin D 50 ng/ ml (n.v. 7.5-41.0), osteocalcin 2.0 ng/ml (n.v. 3-11), PTH 229.7 pg/ml (n.v. 10-65), IGF-1 < 10 ng/ml (n.v. 30-310), TSH 6.84 mUI/ml (n.v. 0.35-3.80), fT4 16.5 pg/ml (n.v. 9.0-15.5) and SHBG 161 nmol/L (n.v. 60-120. Calcifediol supplementation was introduced but the child died for a sepsis at 4 years and 2/12.
Atraumatic fractures may be observed in children with neurodegenerative disorders especially after chronic anticonvulsant medication which may predispose to bone atrophy and demineralization. In this case we have observed a low-turnover osteoporosis related to valproate therapy along with other known causes of increased bone fragility: genetic influences, proteic undernutrition, absent motor support, unbalanced IGF-1 and hormone systems leading to the dramatic absence of bone mineral density and recurrence of pathologic fractures. Polymorphisms in the vitamin D-receptor gene may have accounted for some variation in bone mass of this child, but unfortunately this aspect was not deepened. We believe that DEXA should have a role in monitoring bone loss in epileptic children and in guiding suitable preventive therapy.
PHANTOMS FOR DUAL ENERGY X-RAY ABSORPTIOMETRIC MEASUREMENTS OF INFANTS
W. Koo*, M. Hammami, S. Rani
Wayne State University, Detroit, MI, USA
Currently the commercial phantoms for evaluation of DXA measurements employ anthropomorphic phantoms based on adult lumbar spine bone mass measurements. We report the development of a set of phantoms suitable for evaluation of DXA bone measurements during infancy. Polyethylene bottles of different shapes and capacities (100 to 1000 mL) were filled with either pure olive oil to mimic fat or with a mixture of sodium chloride and potassium mono- and di- basic phosphate dissolved in type I water to mimic lean tissue. Different size borosilicate tubes and flexible polypropylene tubing were filled with calcium carbonate (CaCO3) to mimic bone. Bottles and tubes were taped together in layers to form nine blocks. Each block contained electrolyte water but different quantities of oil and CaCO3. The blocks were assembled adjacent to one another in different combinations to form 4 phantoms (weights 1490g, 3100g, 4560g, and 7360g) and were scanned in triplicates using the infant whole body-scanning mode with a fan beam densitometer (QDR 4500A, Hologic Inc., Waltham, MA). Results show that CV of repeated measurements tend to be highest in the smallest phantom. CV for DXA measured total weight was <3.2% for total weight, <5% for bone area, <3.9% for bone mineral content (BMC), and <3.7% for bone mineral density. The actual weights and the amount of CaCO3 of each phantom were highly significantly correlated with DXA measured total weight and BMC (r = 0.99 each, p<0.001 regression analyses). We conclude that our phantoms made from readily available material is suitable for monitoring the precision error of DXA bone measurements in infants. Its use can be an added quality assurance in the DXA measurement in infants.
NON-INVASIVE BONE MASS MEASUREMENTS PREDICT BONE STRENGTH IN GROWING ANIMALS
M. Koo1*, K. Yang1, P. Begeman1, M. Hammami2, W. Koo2
1Bioengineering Center, Wayne State University, Detroit, MI, USA
2Department of Pediatrics, Wayne State University, Detroit, MI, USA
This study aims to test the hypothesis that noninvasive bone mass measurements can be used to predict bone strength in a piglet model. Dual energy x-ray absorptiometry measurements of bone mineral content (BMC), bone mineral density (BMD), and bone area (BA) were obtained from 4 sets of bones (left and right humeri and femora) of twelve piglets (6-68 d and 2250-17,660 g). Bone strength, defined by the energy to bone failure, fracture moment, and flexural rigidity, was determined from three point bending tests using an Instron material testing system. Regression and correlation analyses used to compare bone mass and bone strength measurements. Agreement between left and right-sided measurements used the Bland and Altman method (Lancet 1986;1:307). Results show that bone mass between left and right extremities was highly correlated (r = 0.96 to 0.99, p=0.001 all comparisons) and was similar for bone strength (r = 0.85 to 0.98, p<0.01 all comparisons). However, based on the standard deviation of the difference between mean measured values from left and right extremities, the agreement between sides was better for bone mass than for bone strength measurements. For each set of bones, bone mass measurements were highly correlated with bone strength measurements (r = 0.68 to 0.99, p<0.05 to 0.001). The predictive ability of bone mass on bone strength varied (adjusted r2 = 0.41 to 0.97) depending on the bone tested and the measurement parameter used, although remained statistically significant in all instances (p<0.05 to 0.001). We conclude that in developing organisms, noninvasive bone mass measurements are correlated with and predictive of bone strength, although bones from the same side and same anatomical site should be used for comparison purposes.
DIRECT MEASUREMENT OF ABSOLUTE BONE MASS OF WHOLE BONES FROM MEN AND WOMEN, 20 TO 90 YEARS OF AGE
L. Klein*, M. S. Wolfe
Case Western Reserve University School of Medicine, Cleveland, OH, USA, 44106
Current measurements of bone mineral density do not accurately reflect bone mass. Sensitive and accurate measurements are critical for evaluating the amount of bone loss in osteoporosis and its proposed treatment modalities. The objective of this study is to quantify and compare significant changes in the mass of human appendicular and axial bones obtained as intact anatomical units from specimens 20 to 90 years of age.
The bones are from the Hamann-Todd collection of the Cleveland Museum of Natural History and were obtained from human skeletons devoid of skeletal disease and/or generalized wasting. Three bones (femur, humerus, scapula) from females and males (n=10-14 for each sex) were studied at each decade from 20 to 90 years of age. Prior to accurate weighing, the bones were defatted, dried, and then compared as a function of age with the youngest group (20-29 years old) designated as the baseline (100%).
Our results demonstrated that the female bones from 20-90 years of age showed larger and similar losses of mass (femur 42.6%, humerus 40.6%, scapula 34.8%) as compared to the male bones (femur 13%, humerus 16.4%, scapula 15.6%). The male bones showed small but significant linear losses (2-3%) starting in the fourth decade. In contrast, the female bones showed larger linear losses (11-12%) starting in the third decade. These data demonstrate that the loss of bone occurs earlier than previously realized and appears to be a normal process that starts when maturation is complete. Garn et al (1967) recognized that age-associated cortical bone loss due to resorption begins by the fifth decade for males and by the fourth decade females. He also recognized that different bones appear to lose mass at somewhat different rates.
EFFECTS OF GENDER AND AGE DIFFERENCES ON THE DISTRIBTUION OF BONE CONTENT IN THE THIRD LUMBAR VERTEBRA
K. S. Tsai*, W. C. Cheng
National Taiwan University, Taipei, Taiwan
To evaluate the effects of age and gender on the distribution of bone mineral content, we performed a cross sectional study on the distribution of bone mineral content in the third vertebrae. The bone mineral content of the whole L3 including the L3 vertebral body and the posterior segment was measured using a lateral approach with a dual energy x-ray absorptiometer on 177 healthy Taiwanese adults including 65 men, and 55 premenopausal and 57 postmenopausal women. We found the proportion of bone mineral content (BMC) in the vertebral body was significantly lower in premenopausal women than in age-matched men (39.1±0.9% vs 50.0±1.7%, p<0.0001). Furthermore, while postmenopausal women showed a decreased proportion of BMC in the vertebral body with increased age (about 0.22% per year, p=0.0001), premenopausal women and men showed a sustained proportion. Thus we concluded that the proportion of BMC distributed in the body of L3 vertebrae was lower in women than in men. The discrepancy of this parameter between the genders was even larger with increased age.
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BONE MINERAL DENSITY IN ADULT-ONSET TYPE 1 DIABETES AT TIME OF CLINICAL DIAGNOSIS
P. J. López-Ibarra1*, M. M. Campos Pastor1, F. Escobar-Jiménez1, M. D. Serrano Pardo1, A. F. García González1, J. D. Luna2, M. E. Ruiz Requena3, M. Aguilar Diosdado4
1Endocrinology Service, San Cecilio University Hospital, Granada, Spain
2Biostatistics Service, University of Granada, Spain
3Biochemical Service, San Cecilio University Hospital, Granada, Spain
4Endocrinology Service, Puerta del Mar University Hospital, Cádiz, Spain
Osteopenia has been demonstrated in type 1 (insulin dependent) diabetic patients (IDDM) on evaluation time of disease. However, little information are available about bone mass, just at the diagnostic moment. Objective: To study bone mineral density (BMD) and remodeling parameters in adult-onset type 1 diabetes mellitus patients at the time of diagnosis of the disease. Subjects and methods: 22 males and 10 females aged 28.43±5.49 (20-39) years were studied promptly after being diagnosed with type 1 DM (WHO criteria). No patients have any antecedents of excessive consumption of tobacco or alcohol and all had an appropiate degree of physical activity and a daily calcium intake. Before any treatment, the clinic history, glycemia, ketonuria, HbA1c basal and glucagon-stimulated peptide-C levels, islet cells antibodies (ICA), glutamic acid decarboxylase antibodies (GADA) and bone remodeling parameters were recorded for all the subjects. Dual X-ray absorptiometry (Hologic QDR 1000) was carried out to measure BMD in lumbar spine (LS), femoral neck (FN) and Ward's triangle (WT). The values were expressed as Z-score (number of SD adjusted by age and sex) and compared with a matched healthy Spanish population. Results: 24 patients (75%) showed positive levels of ICA and/or GADA, while 8 (25%) tested negative. The BMD values (Z-score) were lower among the diabetic patients in LS (-0.61±1.24 SD; p=0.008) and FN (-0.38±1 SD; p=0.003). Twelve patients (40.7%) had a T-score > -2.5 SD and < -1 SD in LS and 14 (46.9%) had the same score in FN, and were classified as osteopenic. There was a correlation between BMD values and C-peptide levels in LS (r=0.23; p=0.02) and FN (r=0.27; p=0.01). The BMD values did not correlate with bone turnover markers, HbA1c levels or immunologic variables. Conclusions: We found reduced bone mass in type 1 diabetic patients at the time of the clinical diagnosis. A high percentage of diabetic patients have osteopenia, which may not, therefore, consider a later complication of type 1 DM. These findings need to be confirmed in larger studies.
BONE MINERAL DENSITY IN SYSTEMIC LUPUS ERYTHEMATOSUS PATIENTS. A CROSS-SECTIONAL STUDY WITH 12-MONTHS FOLLOW-UP
J. Rosa1*, V. Tesaø2, C. Dostál1, J. Zadina1, J. Kafková1
1Institute of Rheumatology, Prague, Czech Republic
2I.Clinic of Internal Medicine, General University Hospital, Prague, Czech Republic
Objective. To evaluate bone mineral density (BMD) in a cohort of outpatients with systemic lupus erythematosus (SLE) and to determine the influence of corticosteroids and disease-related variables at the baseline and during 12-months follow-up.
Methods. BMD of the lumbar spine, proximal femur, and total body was measured by dual energy X-ray absorptiometry (DEXA) in 61 SLE patients (52 premenopausal women, 9 men; mean age 32.3 and 36 years respectively) and 61 healthy controls matched for age and sex. Several disease-related variables including treatment characteristics were recorded. 50 patients (40 women, 9 men) were followed for another 12 months.
Results. With few exceptions the BMD values of all sites were significantly reduced in both women and men (p values 0.000-0.050). Relationship between BMD, prednisone dose and some of disease-related factors are shown in table. During 12 months of follow-up a significant BMD decrease was seen in neck (both sexes), total body (women) and in total proximal femur (men). In women current corticosteroid dose adversely influenced total body mineral content development.
Conclusion. BMD in premenopausal women and in men with SLE is significantly reduced at all measured sites and is adversely influenced by duration of the illness (proximal femur) and prednisone cumulative dose (lumbar spine, total body). Corresponding the cross-sectional phase of the study regions of proximal femur seem to be most vulnerable to further BMD decrease during the follow-up while current corticosteroid dose affects total body mineral content preferentially.
| Variables impact on BMD (r-/p-values) | ||||||
| Variable | LS | FN | WT | Tr | PF | TB |
| Age | -0.15/0.30 | -0.14/0.32 | -0.33/0.02 | 0.04/0.8 | -0.09/0.53 | -0.03/0.81 |
| Illness duration | -0.24/0.1 | -0.36/0.01 | -0.49/0.0003 | -0.29/0.04 | -0.42/0.002 | -0.25/0.09 |
| BMI | 0.1/0.5 | 0.32/0.02 | 0.08/0.58 | 0.41/0.003 | 0.36/0.008 | 0.13/0.37 |
| Prednisone-cumulative dose | -0.31/0.03 | -0.26/0.07 | -0.34/0.02 | -0.27/0.06 | -0.35/0.01 | -0.40/0.006 |
| S-calcitriol | 0.10/0.52 | 0.15/0.31 | 0.14/0.34 | 0.28/0.05 | 0.25/0.09 | -0.09/0.54 |
| Bone specific ALP | -0.04/0.79 | -0.11/0.46 | -0.08/0.60 | -0.10/0.52 | -0.15/0.31 | -0.31/0.04 |
| LS-lumbar spine, FN-femoral neck, WT-Ward´s triangle, Tr-trochanter, PF-total proximal femur, TB-total body mineral content | ||||||
THE INFLUENCE OF HIGH ENERGETIC EXTRACORPORAL SHOCK WAVES ON BONE DENSITIY IN HUMAN CALCANEUM
L. Gerdesmeyer1*, H. Rechl1, T. Schrader1, M. Weber1, A. Heinzel2
1Clinic of Orthopeadic Surgery and Sportstraumtology, Technical University of Munichand, Munich, Germany
2Clinic of Nuclear Medicine, Technical University of Munich, Munich, Germany
Aim: The study will analyze the influence of high-energetic extracorporal shock-waves on the bone-density of the human calcaneum.
Material and methods: In a prospektive controlled study 20 patients, who suffer under a plantar heel spur, were treated, with the extracorporal shock wave therapy. The shock wave application took place in plantar to dorsal direction, so that the calcaneum was placed in the therapy area. The analyse took place in the intraindividual comparison by means of bipartite t-test for dependent variables. The shock wave were emitted with an electro-magnetic-shock-wave-emitter (EMSE 140) with a frequency of 2Hz, using the Epos Fluoro from Dornier Medizintechnik. All patients were treated two times with a defined interval of 2 weeks. 2000 shock wave were applicated at every ESWT session with the mean energy flux density of 0.32 mJ/mm2. The treatment is executed in local anaesthesia under radiological control. The prospective bone mass density (BMD) examinations followed 6 and 12 weeks after the second shock wave application by using the DEXA method.
Results: After 6 weeks the increase of BMD could already be observed not significant (p>0.05). The second control after 12 weeks showed a significant increase the BMD on the treated side (p<0.05). In kontralateral calcaneum and also in the reference areas on lumbar spine and the femur could not be stated a significant change. No complications were observed except of small petechial skin bleedings.
Conclusion: By the influence of high-energetic shock waves the bone-density increases significantly in the treated area of the calcaneum. These changes are limited locally. Same-clever changes in the controlled areas of the lumbar spine, the femur and the kontralateral side do not appear. The results show an osteoinduktive effect which can be used to increase the bone-density.
DO OSTEON POPULATION DENSITIES REFLECT DIFFERENCES IN FATIGUE HISTORY BETWEEN LIMB BONES OF CURSORIAL MAMMALS?
J. G. Skedros
Utah Bone and Joint Center, Salt Lake City, Utah, USA
Department of Orthopaedics, University of Utah, Salt Lake City, Utah, USA
It has been suggested that limb bones of cursorial mammals are optimized for mechanical/energetic efficiency as oscillating pendulums. Consequently, morphologies of limb bones and their associated soft tissues are highly constrained by kinetic/spatial demands, including accommodating stress transfer, enhancing stride length, and minimizing energetic "costs" of adding mass (i.e., maintaining tapered limbs). Optimization theory suggests that weight-bearing strains are highest in distal bones (i.e., nearest the point of impact) and progressively decrease proximally. Investigators have speculated that fatigue microdamage would be most prevalent distally. Since BMUs repair microdamage, limb bones of a cursorial animal should exhibit a distal-to-proximal decrease in population densities of secondary osteons. In turn, between-bone differences in microdamage would not be expected in mature animals. To test these hypotheses, fresh skeletons of 11 wild mature male mule deer were collected and mid-diaphyseal transverse segments were cut from the left proximal phalanx of the medial digit, principal metacarpal, radius, and humerus. A 100micron slice was obtained from each bone of 7 animals, and was used to determine population densities (no./mm2) of secondary osteons and new remodeling events (NREs = resorption spaces and newly forming osteons). An additional 10-to-16mm section obtained from each animal was stained in 1% basic fuchsin and examined by 3 observers for in vivo microcracks (3 slices/bone, 165 total slices). Results of osteon density measurements demonstrate [means and (standard deviations)]: phalanx [10.2 (2.2)], metacarpal [5.9 (2.5)], radius [8.7 (3.0)], and humerus [2.5 (1.9)]. Only two microcracks were identified, and these were found in the radius of one animal. Variations in NREs did not demonstrate progressive differences and were not significant between bones. Absence of significant between-bone differences in microcracks and NREs suggests that these bones are, respectively, adapted for fatigue requirements and in remodeling equilibrium. However, these data fail to demonstrate a progressive distal-to-proximal decrease in osteon density. At high gait speeds, eccentric loading, and energy storage and stress transfer associated with musculotendinous structures may result in relatively lower strains in some distal bones (e.g., metacarpal < radius). Consequently, a progressive distal-to-proximal strain gradient may not occur during gait speeds that most commonly produce microdamage.
THREE-DIMENSIONAL TRABECULAR MICROSTRUCTURE AND BIOMECHANICAL PROPERTIES IN RATS AND MICE WITH HORMONE REPLACEMENT THERAPY
Y. Jiang*, J. Zhao, H. K. Genant
Osteoporosis and Arthritis Research Group, University of California, San Francisco, USA
To capture 3D trabecular microstructure and biomechanical properties, female 6-month old rats were divided randomly into baseline, sham received placebo (sham), ovariectomy received placebo (OVX), and OVX treated with estrogen (HRT) (n=8 in each group) for 9-month post-OVX. 3D trabecular structure was directly measured in the secondary spiongiosa in the lumbar vertebral body L2, using a µCT scanner (Scanco) with 11 µm3 isotropic resolution. Compressive testing of the vertebral body was performed. In a mice study, 70 Swiss Webster mice of 3-month were equally divided into 7 groups: baseline, sham (2 groups), OVX (2 groups), HRT (2 groups). One group of the animals from sham, OVX, and HRT were sacrificed at 5-week post-surgery, and the rest at 13-week post-surgery. The distal femur was scanned using the µCT scanner with 9 µm3 isotropic resolution.
In rats, compared with sham, OVX induced significant changes in 3D trabecular BV and BV/TV (-40%), Tb.N (-28%), Tb.Th (-16%), Tb.Sp (+37%), structure model index (SMI, +187%), degree of anisotropy (DA, +12%), compressive strength (-54%), stress (-63%), stiffness (-62%), and toughness (-42%). HRT prevented OVX-induced changes up to the sham-level. Strong correlations were found between stress and BV/TV or strength and BV (r2=0.88, p<0.0001), between stress/strength and SMI (r2=0.79, p<0.0001), between stress/strength and DA (r2=0.76, p<0.0001), between stress and Tb.N (r2=0.70, p<0.0001). In a multivariate regression model, the addition of DA and Tb.Th to BV and addition of Tb.N and Tb.Sp to BV/TV significantly increased the correlation with the strength and stress (r2=0.91, p<0.01), respectively. In mice, at 5-week post-surgery, OVX induced significant changes in BV/TV (-50%), Tb.N (-29%), Tb.Th (-8%), Tb.Sp (+54.38%), SMI (+14%), and DA (-10%), compared with sham. These changes were similar at 13-week post-surgery. HRT prevented OVX-induced changes up to the sham level.
Thus, OVX induced dramatic changes in 3D trabecular structural characteristics in rat and mice and a decrease in biomechanical properties in rat vertebral body. 3D trabecular structure was closely associated with biomechanical properties. The combination of trabecular bone volume with trabecular structural parameters improves predicting biomechanical properties. HRT prevents OVX-induced bone loss without anabolic effect.
STRUCTURAL COMPLEXITY OF CANCELLOUS BONE: A FRACTAL ANALYSIS
I. H. Parkinson1,2*, N. L. Fazzalari1,2
1Division of Tissue Pathology, Institute of Medical and Veterinary Science, South Australia
2Department of Pathology, Adelaide University, South Australia
The complex structure of cancellous bone means that mass is not the sole determinant of its mechanical properties. Measurement of the structural entities by conventional histomorphometry relies on parameters calculated from mathematical models of cancellous architecture. Fractal analysis is a model independent method which describes the complexity of morphological 'bone compartments', namely surface detail, shape or form of individual trabeculae and overall spatial arrangement of cancellous architecture. This technique enables change to cancellous architecture, mediated by bone cell activity, to be quantified, thus giving greater understanding of the mechanisms involved in trabecular transformations with disease.
Two hundred and eighty histological sections of cancellous from 8 skeletal sites were analysed. All samples were from skeletally normal individuals (184 from males with a mean age of 59 years and 96 from females with a mean age of 55 years). Fractal analysis and conventional histomorphometry were performed using a Quantimet image analyser. 3 fractal dimensions, BV/TV, BS/TV, BS/BV, Tb.Th, Tb.Sp, Tb.N and Trabecular pattern factor were determined from each section. Stepwise multiple regression was performed to determine which histomorphometric parameter correlated best with each fractal dimension.
Fractal 1 (D1) as a descriptor of surface complexity is significantly correlated with BS/BV (R=0.69, p<0.0001). Fractal 2 (D2) as a descriptor of the shape or form of individual trabeculae is significantly correlated with BV/TV (R=0.93, p<0.0001). Fractal 3 (D3) as a descriptor of the overall spatial distribution of the trabecular structure is significantly correlated with Tb.Sp (R=0.61, p<0.0001). These data are the same for both males and females.
Multiple regression analysis shows that the three fractal dimensions are related to the magnitude of specific conventional histomorphometric parameters. In particular, the fine surface detail (D1) is a function of change in specific bone surface (BS/BV). The shape or form of individual trabeculae (D2) is related to the amount of bone present (BV/TV) and the overall spatial distribution of the trabecular structure (D3) is related to the separation of the trabeculae (Tb.Sp). These data show that fractal dimensions describe the structural complexity of specific 'bone compartments' within cancellous bone.
A SIMPLE, FAST AND REPRODUCIBLE FULLY AUTOMATED METHOD FOR STRUCTURAL AND DYNAMIC BONE HISTOMORPHOMETRY
D. Brown*, S. Picard, J. P. Brown
Groupe de Recherche sur les Maladies Osseuses, Centre de Recherche du CHUL, Université Laval, Canada
Various histological parameters are altered in most metabolic bone diseases. Histomorphometry still remains an absolutely essential tool in clinical research for assessment of cellular and tissular bone dynamics as well as bone microarchitecture. Many methods have been developed for quantitative evaluation in bone morphometry. Semi-automated approaches were described for a long time as the most simple and reproducible methods to measure main primary parameters in bone morphometry. With the development of new high performance image-analysis systems, automated approaches appear to be valuable for measurements of most static and dynamic parameters but not yet for osteoid. By using a black and white CCD cooled camera and NOVA BIOQUANT, R&M Biometrics image-analysis software we have developed a simple reproducible fully-automated method. This method improves both precision and rapidity for measurement of most formation and resorption as well as microarchitecture assessments. Each parameter has been validated for accuracy, repeatability, intermediate precision and linearity in agreement with ICH validation guidelines. To validate our approach 12 samples from different metabolic bone disorders were tested; 5 postmenopausal osteoporosis, 1 corticosteroid-induce osteoporosis, 1 renal osteodystrophy, 2 osteomalacia and 3 histologicaly normal bone. The automated method showed a very good correlation and linearity for all parameters. The coefficient of variation (CV) for intra-observer repeatability and intermediate precision when assessing this automated method for each of these parameters ranged as follows:
Repeatability CV: BV 0.5%, TbN 0.3%, TbTh 0.5%, TbSp 0.2%, OV relative 2.0%, OV absolute 1.6%, OS 0.7%, OTh 1.8%, ES 2.7%, MAR 3.5%.
Intermediate precision CV: BV 3.0%, TbN 0.3%, TbTh 2.8%, TbSp 1.1%, OV relative 5.0%, OV absolute 2.6%, OS 3.4%, OTh 1.8%.
Inter-observer analysis is underway and seems so far to be promising. If we compare both methods, automated measurements save 43% in morphometric analysis time. With the latest improvements in computerized image analysis systems, bone histomorphometry has became a more reliable and less expensive science for assessing pathophysiology of metabolic bone diseases.
RELATIONSHIP OF THE BONE HISTOMORPHOMERY TO THE LEVELS OF VITAMIN K ANALOGUES IN BONE OF THE TREATMENT WITH PHENYTOIN ALONE AND IN COMBINATION WITH ALFACALCIDOL IN GROWING RATS
K. Onodera1*, A. Takahashi2, H. Wakabayashi3, J. Kamei4, H. Furuta1
1Department of Dental Pharmacology, Okayama University Dental School, Okayama, Japan
2Division of Pediatric Dentistry, Department of Lifelong Oral Health Sciences, Tohoku University Graduate School of Dentistry, Sendai, Japan
3Department of Biophysical Chemistry, Niigata College of Pharmacy, Niigata, Japan
4Department of Pathophysiology & Therapeutics, Faculty of Pharmaceutical Sciences, Hoshi University, Tokyo, Japan
We have reported that subcutaneous administration of phenytoin at 20 mg/kg/ day for 5 weeks caused decreases in bone mineral density (BMD) and did not affect the growth curves of rats. Combined administration of alfacalcidol with phenytoin prevented the reduction of BMD induced by phenytoin. In this study, we attempted to clarify the mechanism of bone-loss induced by phenytoin using histomorphometric measurements and the determinations of vitamin K analogues. In histomorphometric analysis, phenytoin decreased trabecular bone volume and trabecular thickness, and increased osteoclast numbers per area of bone surface in the secondary trabecular bone of the tibia. Additionally, there was no significant difference in osteoid thickness. In the group treated with alfacalcidol and phenytoin, a decrease in trabecular bone volume and trabecular thickness was prevented and there was no increase in osteoclast numbers per area of bone surface compared with the vehicle-treated group. The results of the determination of vitamin K1 and vitamin K2 analogues (MK-n), phenytoin decreased the levels of vitamin K1 and vitamin K2 (MK-4, MK-5, MK-6) in femoral metaphysis and these of vitamin K1 and vitamin K2 (MK-4) in femoral diaphysis. Co-administration of alfacalcidol with phenytoin prevented such decrease in some degrees in vitamin K1 and vitamin K2 levels except for vitamin K1 in femoral metaphysis. An adequate correlation is estimated from the results of bone histomorphometric measurement and the levels of vitamin K1 and vitamin K2 analogues between vehicle treated group and phenitoin treated group. Biochemical data indicated that the serum osteocalcin, a marker of bone formation, was decreased significantly in the phenytoin-treated group compared with the vehicle-treated group. From these findings, the treatment with phenytoin induced osteopenia, which may be due to bone loss by inhibiting bone formation and/or by accelerating bone resorption rather than osteoid accumulation. Moreover, it was suggested that phenytoin affected the vitamin K metabolism because of the relation between bone-loss and vitamin K1 and vitamin K2 (MK-4, MK-5, MK-6) decrease in bones in phenytoin treated group.
ANABOLIC EFFECTS OF COXARTHROSIS CONFER PROTECTION AGAINST INTRA-CAPSULAR HIP FRACTURE
G. R. Jordan*, N. Loveridge, J. Power, N. Rushton, J. Reeve
University of Cambridge, Cambridge, UK
Patients with coxarthrosis (cOA) have a reduced incidence of intra-capsular femoral neck fracture suggesting cOA offers protection. In a previous study we demonstrated that the femoral neck in patients with coxarthrosis had increased %cancellous area (Cn.Ar), trabecular thickness and connectivity and suggested that these enhancements contribute to the protection associated with the condition. The aim of the present study was to assess if the differences between cases and controls are the result of increased cancellous bone formation and/or decreased cancellous bone resorption relative to controls. In addition, the role of osteocyte lacunar density in this process was investigated.
Whole cross section femoral neck biopsies were obtained from 11 patients with cOA and histomorphometric parameters were compared in 4 anatomical regions to 11 age and closely sex matched cadaveric controls. Overall, %Osteoid Surface/ Bone Surface was increased in the cases (+206%; p=0.014: n=7) while Eroded Surface/Bone Surface was unchanged (p=0.38: n=7). Cancellous wall width was higher in cOA, (+20%; p<0.001, at the level of the basic multicellular unit). Cancellous lacunar density was decreased in cOA (-22%; p<0.0001) and there was a significant inverse relationship between osteocyte lacunar density and %Cn.Ar (adj. r2=-0.38; p<0.001). The effect of region was not significant for any parameter.
This study suggests that the increased cancellous bone mass and connectivity seen in cases of cOA is due to increased cancellous bone formation rather than decreased bone resorption relative to controls. The increase in cancellous bone in cases of cOA might be explained in part by the reduction of cancellous lacunar density. This suggests that osteoblast transformation into osteocytes is deferred thereby increasing their longevity and productive life. Investigating how cOA modulates the apportioning of bone close to this common site of fracture may provide insights that lead to novel preventative strategies against hip fracture based on the local delivery of anabolic agents.
FRACTAL DIMENSION AS A DIAGNOSTIC TOOL FOR ANALYSIS OF METABOLIC BONE DISEASE
J. J. Siller Leyva1, D. Cohen2*, C. E. Román-Velázquez1, A. Rosas3
1Centro de Investigación en Ciencia Aplicada y Tecnología Avanzada IPN, México, México
2Centro Médico Palmas, México, México
3Instituto Tecnológico de Estudios Superiores de Monterrey, Tlalnepantla, México
Correlation was made between the values of fractal dimension of normal trabecular bone and bone abnormalities. We have calculated the fractal dimension of bone trabecula from healthful individuals and patients with different bone diseases. We have developed different computational procedures for the calculation of fractal dimension of bone trabecula and compared it with the use of Magnetic Resonance and CT Scan images in order to establish the best condition for the determination of fractal dimension of bone. We found that the box counting method applied to CT Scan images provides the best results, and this method could be useful for the analysis and diagnostic of metabolic bone diseases.
THE BONE'S DISORDER IN CHILDREN TREATED FOR ASTHMA BRONCHIALE
M. Bayer1*, J. Novak2, P. Visek2, V. Derner3
1Paediatric Department, Charles University, Prague, Czech Republic
2Department of Clinical Immunology and Allergology, Litomysl Hospital, Czech Republic
3Institute of Clinical Immunology and Allergology, Hradec Kralove, Czech Republic
The aim of this study was to assess the influence of childhood asthma and its therapy on ultrasound bone parameters.
Methods. 70 patients aged 4-17 years were treated for asthma over a period of 12-40 months. The basis of therapy was fluticasone propionate (FP) or nedocromil sodium (NED). Calcaneal velocity of sound (VOS) and broadband ultrasound attenuation (BUA) were measured using CUBA Clinical (McCue Ultrasonics, UK) device.
Results. The difference of the mean VOS and BUA values between asthma patients and control group was significant after one year of NED therapy (p=0.029 and 0.01, respectively). The difference of the mean VOS values between asthma patients and control group was significant after one year of FP therapy with an average daily dose of 205microg (p=0.003). The increase in the cumulative dose of FP is associated with proportional decrease in VOS and BUA values. There were significant differences between the mean VOS values of FP group (cumulative dose 100-200mg/year) and NED (p=0.036) and between the mean BUA values (cumulative dose >200mg/year) and NED (p<0.001).
Conclusion. Asthma bronchiale in childhood has a negative influence on bone mass by itself. Therapy with inhaled fluticasone propionate is worsening the bone disorder.
EVALUATION OF BONE MASS AND BONE QUALITY IN CHILDREN WITH ASTHMA TREATED WITH ANTI-INFLAMMATORY STEROIDS BY DXA AND QUS: PRELIMINARY RESULTS
M. Jaworski1*, K. Nowacka2, R. S. Lorenc1
1Dept. of Bioch. and Exp. Medicine, Children's Memorial Health Institute, Warsaw, Poland
2Dept. of Allergology, Spec. Children's Hospital, Warsaw, Poland
Quantitative ultrasound (QUS), because of potential lack of irradiation is expanding very rapidly. Equipment and potential of measuring are developing focusing in diagnostic and monitoring of treatment. There are still limitation in work concerning children especially with clinical utilization of this technique.
The aim of this study was evaluation of skeleton in children with asthma treated with steroids using 3 ultrasound technic (focused on trabecular weight-bearing bone, cortical not weight-bearing and cortical weight-bearing bone) compared to DXA method. It should enable evaluation of response of bone on steroid therapy and to find possible difference of behavior of various kind of bone.
DPX-L apparatus (DXA) with pediatric software was used for total body and Ap spine measurements; Achilles Plus apparatus (QUS) with pediatric equipment for heel measurement and Omnisense apparatus (QUS) for distal radius and midshaft tibia.
Group of 27 children aged 6-12 yrs of both sexes with asthma were included in the study after obtaining justification of Ethical Committee and informed consent of interested parties.
By the ultrasound method, the lowest mean Z-score value was reached for cortical not weight-bearing bone (distal radius SOS: -0.39±0.74). Weight-bearing bone demonstrated slightly higher value (midshaft tibia SOS: -0.26±1.03). Surprisingly, the highest mean Z-score was for weight-bearing trabecular bone (calcaneal Stiffness: 0.42±0.97). DXA method showed comparable results. Mean Z-score being -0.36±0.69 for Ap spine BMD and 0.07±0.58 for total body BMD. There were no statistically significant differences between means of Z-scores.
Preliminary results pointed on, that deficiencies of Z-score values observed at the beginning of the study were comparable in all studied sites. Maybe, prospective data enable to find possible difference between behavior of various kind of bone during anti-inflammatory steroids therapy.
CHARACTERIZATION OF BONE MASS, STRENGTH, AND TURNOVER IN PREDNISOLONE-ADMINISTERED MINIPIG AS A MODEL OF STEROID-INDUCED OSTEOPOROSIS
S. Ikeda1*, M. Morishita2, H. Tsutsumi3, S. Arita1, T. Nakamura1
1Department of Orthopaedic Surgery, University of Occupational and Environmental Health, Kitakyushu, Japan
2Chugai Pharmaceutical Company, Tokyo, Japan
3CSK Research Park, Inc., Nagano, Japan
To examine the effects of glucocorticoid administration in Göttingen minipig as a model of drug-induced osteoporosis, sixteen female minipigs, 8 months of age, were assigned to 3 groups. Four animals were sacrificed at start for baseline control. Six were subcutaneously injected at a daily dose of prednisolone 0.5 mg/kg body weight (BW) dose in five days a week for 26 weeks (steroid group), and six received vehicle (control). BW and biochemical markers in serum and urine were measured at 0(start), 13, and 26 weeks. At sacrifice, the 2nd lumbar vertebral body (L2) and the left femur were dissected out. After measuring sizes, bone minerals were measured by DXA at the mid portions of L2 and femur. Then, mechanical tests for failure, compression on L2 mid-segment (6 mm) and three-point bending on mid-femur (50 mm), were performed.
Increases in BW did not significantly differ between steroid and control groups. The length values of L2 and femur in steroid group were significantly smaller than those of controls (Tukey-Kramer post hoc test). The bone width, however, did not significantly differ from the controls.
Serum levels of bone alkaline phosphatase and osteocalcin (OC) in steroid group significantly reduced compared to start at 13 and 26 weeks. Their OC levels were significantly smaller than the control levels as well. Their urinary levels of NTx in steroid groups also significantly reduced compared to both the start and control levels. While BMD values of mid L2 in steroid group did not differ from those of the controls, their ultimate load values significantly reduced compared to the controls. Structural stiffness values significantly reduced compared to the baseline levels. BMD and breaking load values of the mid-femur in steroid group significantly reduced compared to the controls. Maximum energy absorption values in steroid group were also reduced.
These data clearly demonstrated that mechanical properties and bone minerals of the lumbar bone and femur were reduced by glucocorticoid administration. Bone markers compatibly suggest reduction of bone turnover in the early period of administration. Mechanical tests and BMD measurements seem to indicate deterioration of trabecular bone structure in the lumbar bone.
BONE LOSS IN PATIENTS ON CORTICOSTEROID THERAPY: A LONGITUDINAL STUDY - ONE YEAR DATA
A. Stewart*, D. M. Reid
Osteoporosis Research Unit, Dept of Medicine and Therapeutics, University of Aberdeen, Aberdeen, UK
Corticosteroid therapy is a risk factor for osteoporosis. We initiated a longitudinal study examining patients commencing corticosteroid therapy. Measurements were taken at baseline and then at 4 month intervals, using DXA of the spine and hip and quantitative ultrasound (QUS) of the heel. 78 patients were enrolled, of which 22 had rheumatoid arthritis and 20 polymyalgia rheumatica. The remaining patients had a variety of rheumatological (n=22) or other (n=8) conditions. DXA was measured using a Lunar Expert and QUS with a Osteometer DTU-One. This is an observational study and baseline reports of DXA scans were given to the physician and appropriate prophylactic treatment commenced if necessary. We report the data from the first year of the study when 64 have completed one year of follow-up. Of these 43 had complete data for all 4 bone mass measurements, with 23 of these having commenced treatment while the remaining 20 had not. For those not on treatment the median change in bone mass is as follows: BUA –0.89%, SOS –0.12%, DXA Spine –2.64%, DXA neck –3.88%, DXA total hip +4.49%. For those on treatment the results are respectively: +0.18%, -0.28%, +0.11%, -3.82%, +5.86%, although none of the differences were significant compared to the untreated group. However, there did appear to be an effect of disease/condition. For BUA there was a significant difference (p=0.035) with those with RA showing a larger decrease (mean loss = -4.7%) compared to the others (PMR = +0.24%, other rheumatological = +0.26%, all others = +0.01%). This was also shown for DXA Neck (RA = -8.05%, PMR = -1.59%, other rheumatological = -5.55%, all others = -1.50%; p=0.037). In those who were treated there appears to be an influence of baseline bone mass (DXA L2-L4 and neck only) since those categorized as osteopenic (T<-1.0) had increased bone loss when compared to those with osteoporosis (T<-2.5) indicating that some drug therapies are more effective with lower bone densities. In conclusion the amount of bone loss due to corticosteroid use seems to be influenced by the underlying condition and baseline bone mass.
STUDY OF BONE MINERAL DENSITY IN PATIENTS WITH BRONCHIAL ASTHMA ON GLUCOCORTICOID THERAPY
I. Baranova1*, N. Toroptsova2, K. Gadjiev1, N. Demin2, A. Chuchalin1
1Pulmonology Research Institute, Moscow, Russia
2Institute of Rheumatology, Moscow, Russia
The main predisposing factor to osteoporosis is effect of glucocorticoids (GCs) in patients with bronchial asthma. Oral GCs have the most important adverse events, but inhaled GCs have less effect on bone metabolism.
Objective: To assess bone loss in patients with bronchial asthma, receiving long term inhaled (LTIGT) or oral (LTOGT) glucocorticoid therapy.
Methods: The bone mineral density (BMD) was measured at lumbar spine and femoral neck using dual energy X-ray absorbtiometry (Hologic QDR 4500A). The patients were divided into 3 groups: 1 group - 20 patients with LTIGT (mean dose 1326±456 mcg/day of beclomethasone dipropionate equivalent, mean duration of therapy 3.31±1.14 years); 2nd – 56 patients with LTOGT (mean dose 10.10±6.01 mg/day of prednisolon, mean duration of therapy 8.0±6.11 years); 3rd – 33 patients without GC therapy.
Results: We observed significant difference in BMD between patients with LTOGT and without GC therapy in lumbar spine region (p<0.05), but we didn’t reveal significant difference in BMD of lumbar spine and femoral neck between groups of patients taking LTIGT and without GC therapy.
Conclusion: Our study demonstrated the deleterious effect of LTOGT, but we did not find detrimental effect of inhaled glucocorticoids. Further prospective study is necessary to answer the questions about effect of LTIGT on bone metabolism.
P458 T
Withdrawn
RAPID NORMALIZATION OF SERUM OSTEOCALCIN LEVELS FOLLOWING TERMINATION OF DEXAMETHASONE TREATMENT IN MONKEYS
R. Brommage*, C. Allison
Wake Forest University, Winston-Salem, USA
Glucocorticoid-induced osteoporosis involves an inhibition of osteoblastic bone formation. The objective of this study was to characterize the responses to short-term glucocorticoid administration and its withdrawal in monkeys.
Adult female cynomolgus monkeys were divided into two groups with one group receiving subcutaneous injections of 2 mg/kg dexamethasone phosphate on days 1, 3, 5, 7, 9 and 11. Blood and body weight were obtained from all monkeys after a morning fast at baseline and on days 4, 8, 12 and 19 with measurements made of serum levels of ionized Ca, cortisol, glucose, IGF-I, osteocalcin, CTX and PTH.
Dexamethasone treatment rapidly blocked endogenous cortisol production while producing transient hyperglycemia (113 vs 71 mg/dl glucose on day 4), mild hypercalcemia (increase of 0.06 mM), elevated levels of serum IGF-I (687 vs 350 ng/ml) and a 70% reduction in serum levels of osteocalcin (15 vs 50 ng/ml). Bone resorption as indicated by serum CTX levels decreased slightly (4.7 vs 6.7 nM) during dexamethasone treatment whereas serum PTH levels and body weight were not affected. Serum levels of cortisol, glucose, ionized Ca, IGF-I and osteocalcin all returned to control values eight days following termination of dexamethasone treatment. In contrast, serum CTX levels remained depressed.
These data demonstrate that monkeys respond to dexamethasone administration similarly to humans with a rapid reduction in bone formation as indicated by serum osteocalcin values. This depressed bone formation rapidly returns to normal levels once dexamethasone treatment is stopped. Dexamethasone treatment also inhibits bone resorption, but the normalization of this parameter requires more than eight days.
COMMUNITY USE OF ORAL GLUCOCORTICOSTEROIDS IN ICELAND AND PROPHYLACTIC TREATMENT FOR STEROID-INDUCED OSTEOPOROSIS IN DAILY CLINICAL PRACTICE
U. I. Juliusson1, F. V. Gudjonsson2, B. Gudbjornsson1,3*
1Department of Medicine, Akureyri, Iceland
2Health Care Center, Akureyri, Iceland
3Centre for Rheumatology Research, Reykjavik, Iceland
Objective: The use of oral corticosteroids is one of the most common causes of iatrogenic osteoporosis. Recently, therapeutic guidelines dealing with the skeletal complication of corticosteroids have been published. Therefore, it is of interest to evaluate the indication for long-term therapy with corticosteroids and the frequency of active intervention against steroid induced osteoporosis in daily clinical practise.
Material and methods: After approval by the Committee on Medical Ethics and The Commission of Data Protection all recipes on corticosteroids in drugstores during two years period in the area of north-east Iceland (population 26,664) were gathered. Thereafter, information was collected from medical records at the Health Care Centres and the local Hospital. Patients who were taking per oral corticosteroids for at least three months per year or in a repeated period (totally three months annually) were included in the study. These patients also received a questionnaire concerning hormone replacement therapy and dieatary consumption of calcium and D-vitamin.
Results: 191 patients were included in the study, or 0.7% of the population. The mean age was 66 years (17-93) and 55% were females. Rheumatic and pulmonary disorders were the most frequent indication for the treatment. 20% of the patients had expired an osteoporosis related fractures and 26% of the patients had supposed corticosteroids induced osteoporosis. 52% of the patients were on sublimentary D-vitamin (fish liver oil) and 37% were taking calcium-tablets, while 91% of the patients were consuming milk products regularly. Nine percent of the patients were taking bisphosphonates and 21% of postmenopausal women were on hormone replacement therapy.
Conclusions: Relatively few patients on long term corticosteroids are on primary prevention against corticosteroids induced osteoporosis, although several patients are on D-vitamin and calcium sublimentation. Specific treatment against osteoporosis was in most cases instituted secondary to osteoporotic complications. Thus, corticosteroids prescribing doctors are urged to applicate the new therapy alternatives against corticosteroid-induced osteoporosis to their patients.
EFFECT OF COFFEE CONSUMPTION ON BONE METABOLISM
W. Sakamoto1*, J. Nishihira2, H. Isomura1, K. Fujie1, T. Iizuka3, M. Ozaki4, S. Yukawa4
1Dept. of Biochemistry, School of Dentistry, Hokkaido University, Japan
2Central Research Institute, School of Medine, Hokkaido University, Japan
3Dept. of Oral Pathology, School of Dentistry, Hokkaido University, Japan
43d Internal Medicine, Wakayama Medical College, Japan
Coffee effects on bone metabolism are still controversial, although several studies have suggested that caffeine and/or heavy coffee consumption is associated with a significant increase in risk of fracture, osteoporosis, and periodontal disease. Therefore, we tried to clarify relationship between coffee consumption and bone metabolism in Male Wistar rats. Forty-eight male Wistar rats were assigned to three treatment groups: control-diet group (n=16; coffee-free diet), 0.62% coffee-diet group (n=16, diet supplemented with 6.2g/kg of the control diet), and 1.36% coffee-diet group (n=16, diet supplemented with 13.6g/kg of the control diet) and were maintained on an experimental diet for 140 days. Although caffeine in serum was not detected in rats fed the control diet, after 140 days of the 0.62% coffee-diet led to an increase in caffeine concentration to 0.53±0.11 microg/ml and the 1.36% diet led to one of 1.77±0.22 microg/ml. No significant differences on body weight change, serum and urinary biochemical markers of bone metabolism, and bone histomorphometry were found between coffee diets groups and control diet group, except that urinary phosphorus excretion after 140 days of the coffee-diets significantly increased as compared with the control-diet (p<0.05). In addition, the coffee-diets could not affect production of TNF-alpha and IL-6, which have been implicated in the pathogenesis of bone loss together with Interleukin-1beta. From these results, the present study strongly indicates that coffee does not stimulate bone loss and is one of the safety beverages.
RATIONALE FOR CALCIUM/VITAMIN D-SUPPLEMENTED YOGURTS IN THE ELDERLY
V. Coxam1*, N. Gaumet-Meunier1, M. J. Davicco1, P. Lebecque1, M. Brandolini1, E. Postaire2, J. P. Barlet1
1INRA - CRNH Clermont-Ferrand 63122, France
2Danone Vitapole, Le Plessis Robinson, France
A potential etiological factor for osteoporosis is the vitamin D deficiency that occurs with advancing age. We thus carried out a double-bind pilot study on 42 institutionalized elderly subjects (mean age 81.4 years) to study the impact of vitamin D fortified-yogurts consumption in the management of hypovitaminosis D. No volunteer had received vitamin D or other compounds known to affect the metabolism of phosphorus and calcium within 6 months before the study. After assessing dietary intake, mental test, outdoor and physical activity scores, volunteers were randomly divided into 3 groups. Each elderly consumed 2 yogurts per day for 1 month. The first 15 days, group 1 received 2 unfortified-yogurts (172 mg Ca) and the 15 other days 1 unenriched + 1 fortified-yogurt (300 mg Ca + 0.94 microg vitamin D). Inversely, group 2 consumed 1 fortified + 1 unfortified-yogurt for 15 days and then, 2 unenriched-yogurts. Group 3 ate 2 enriched-yogurts during 1 month. At J0, J14 and J28, 25(OH)D, 1,25(OH)2D, calcium, creatinine, osteocalcin (a marker for osteoblastic activity) were measured in plasma. Calcium, creatinine and deoxypyrydinoline (bone resorption) were assessed in urine.
In the 3 groups, mean calcium consumption (818±SD 81 mg/d) and vitamin D intake (1.66±SD 0.11 microg/d) were under european recommended dietary intake. Mean basal 25(OH)D level was <12 ng/ml, the usual cutoff for vitamin D deficiency. Plasma 1,25(OH)2D values were also very low (18.59±SD 2.77), showing, again, a high prevalence of hypovitaminosis D in this population. Supplementation increased plasma 1,25(OH)2D concentrations after 15 (group 1, 26.97±SD 2.85 vs 20.29±SD 3.07; group 2, 28.03±SD 3.35 vs 19.61±SD 3.36) or 30 days (group 3, 30.82±SD 3.59 vs 18.55±SD 2.77), while no significant change was observed in the 25(OH)D status. In the same way, bone markers did not vary.
In conclusion, our study demonstrates that severe vitamin D deficiency commonly present in institutionalized elderly, which appears to be of pathophysiological importance in the development and severity of senile osteoporosis, might be partially corrected by vitamin D and calcium fortified-yogurt. Fortified yogurts could thus be a useful mean to improve the vitamin D status in the elderly.
EFFECTS OF SURGERY ON BONE MINERAL DENSITY IN OBESE PATIENTS
M. L. Fernandez-Soto*, E. Ferrandiz, M. Quesada, V. Luna, F. Leruite, A. Gonzalez, P. Mezquita, F. Escobar-Jimenez
University Hospital San Cecilio, Granada, Spain
Background: Published data about the influence on bone metabolism of surgical treatment of obesity are scanty and matter of controversy.
Objective: To compare bone mineral density (BMD) in obese patient before and two year after undergoing vertical-banded gastroplasty (VBG) or distal gastric by-pass (DGB) as a treatment of their obesity.
Design: We recruited 57 women and 20 men who met National Institute of Health criteria for obesity surgery. VBG (n=48 patients) and DGB (n= 29 patients). Bone mineral density (BMD) was measured at the lumbar spine (LS) and three upper femoral sites (FN, FT, WT) before, one and two years after surgery and compared with an age- and sex-matched non-obese control group.
Results: BMD was significantly greater in preoperative obese patients versus controls (p< 0.001 at all sites). The obese patients showed a weight reduction one year after VBG (mean loss 42 kg, p<0.001) and DGB (mean loss 51 kg, p<0.001). At the two-year follow-up, the patients showed a reduction in BMD of 6.1% at LS, 10% at FN, 9.6% at FT and 10.5% at WT, with no significant differences according to the surgical approach. The percentage of patients with osteopenia-osteoporosis was significantly higher two years after surgery, both in lumbar spine (11% vs 25%, p<0.05) and hip (4% vs 29%, p<0.01). Postmenopausal women showed the greatest bone loss with osteopenia-osteoporosis in 50% of cases in LS (p<0.001) at 2-year follow up. A linear correlation was found between the percentage of BMD and the excess of weight lost at LS (r=0.36; p<0.01), FN (r=0.38; p<0.01) and FT (r=0.30; p<0.05).
Conclusions: The obese patients had an increased BMD at baseline. A moderate BMD reduction was found after bariatric surgery, specially in the hip and in postmenopausal women, with a peak after 1 year of follow-up. The bone loss is not affected by surgical technique and is mainly related to weight loss. Serial BMD should be measured in obese patients undergoing bariatric surgery and above all, in postmenopausal women as a group of special risk.
EFFECT OF SEASON ON 25-HYDROXY VITAMIN D AND PARATHYROID HORMONE IN A HEALTHY POPULATION OF WESTERN CANADIANS
D. Rucker*, J. A. Allan, G. F. Fick, D. A. Hanley
Faculty of Medicine, University of Calgary, Calgary, Canada
Secondary hyperparathyroidism resulting from Vitamin D insufficiency has been associated with a loss of bone mass. Individuals living in countries at higher latitudes are more prone to 'seasonal' vitamin D insufficiency, due to limited skin synthesis of vitamin D during the winter months. In this study we evaluated the seasonal prevalence of vitamin D insufficiency and variations in 25-hydroxy vitamin D (25OHD), as well as corresponding levels of parathyroid hormone (PTH) in a healthy, community dwelling population of Canadians at 51.4 North.
A total of 204 subjects (66 men and 137 women, aged 27-89 yrs) were randomly selected from the Calgary cohort of the Canadian Multicenter Osteoporosis Study. Individuals were excluded if baseline 25OHD <25 nmol/L or they were taking >200 IU vitamin D/day. Fasting overnight blood samples were collected in February, May, August and November. Commercial RIA assay kits (DiaSorin Inc.) were used to measure serum PTH and 25OHD. Regression models for longitudinal data were used to assess the effect of season on 25OHD as well as PTH.
The prevalence of vitamin insufficiency (defined as 25OHD <40 nmol/L) was 20% for February, 18% for May, 9% for August and 18% for November. Serum levels of 25OHD and PTH (geometric mean±SD) are shown in the table below. In the prediction of PTH, 25OHD was not significant (P=0.108).
This study documents the predicted rise of 25OHD during the spring and summer months and a subsequent decrease during fall and winter months in a healthy population of Canadians. PTH values declined in the summer, but also in the fall, so that the anticipated reciprocal relationship between 25OHD and PTH was not documented. Thirty-four percent of all participants had vitamin D insufficiency at least once during the year, supporting a recommendation for dietary vitamin D supplementation in Western Canada.
| FEB | MAY | AUG | NOV | |
| 25OHD (nmol/L) | 53.4±1.5 | 57.6±1.5b,c | 67.8±1.4b,c | 49.9±1.4a,c |
| PTH (ng/L) | 35.5±1.6 | 35.6±1.6 | 32.4±1.6a,d | 30.4±1.7b,d |
| Values designated by asterisks differ
significantly from FEB (aP<0.05; bP<0.001); cAdjusted for age, sex, BMI (kg/m2), vitamin D supplementation (<200 IU) and travel to lower latitudes; dAdjusted for age, sex, BMI (kg/m2) and 25OHD |
||||
ALCOHOL ABUSE AND OSTEOPOROSIS
A. Humphries1*, F. Alam2, P. Kyd1, A. Fairney1
1Imperial College School of Medicine, London, UK
2The Max Glatt Alcohol and Drug Dependence Unit, Middlesex, UK
Chronic alcohol abuse has been reported to decrease bone density and increase the incidence of fractures. In vitro and in vivo studies have shown that alcohol has an inhibitory effect on the osteoblast and can stimulate osteoclast function, thus uncoupling the bone remodelling cycle. However, there is some evidence that social drinking is associated with higher bone mineral density in men and women [1]. We have undertaken a cross sectional study to assess bone density and metabolism in chronic alcoholics (n=40) (35 male, 5 female), mean alcohol consumption per week, 241 units (range 60-638) (mean age 40.2 years) undergoing detoxification.
BMD (distal forearm Osteometer DTX 200) showed 22/40, (33%) of subjects with osteopenia, 5/40, (12%) with osteoporosis and 18/40 (47% with normal results (WHO criteria). These values correlated with age and BMI, p<0.05, but not with alcohol intake, serum gamma glutamyl transferese (GGT), serum C telopeptide of type 1 collagen (CTX, Cross Laps). The mean daily calcium intake was 696 mg and GGT levels were above the reference range (10-60 iu/L) in 78% of patients (mean (SD) 310 (75) iu/L). There was no difference in liver function, bone resorption markers, alcohol dependency score (mean value 38.25 (>30 severe dependency) or alcohol intake between those subjects with normal bone density and those with bone loss (osteopenia/osteoporosis). Also, there was no evidence of increased bone resorption from the biochemical results, serum CTX 2519.7 (204) mean (SD) pmol/ L, reference range 302-7208 pmol/L.
These results suggest that high alcohol consumption does not have as significant an effect on bone loss and bone turnover as might be expected, and that age and BMI are important risk factors for osteoporosis for patients who abuse alcohol.
1. Holbrook TL, Barrett-Connor E, British Medical Journal 1993 306 1506-09.
OSTEOMALACIA IN IMMIGRANTS FROM THE MIDDLE EAST
J. Feldkamp*, M. Schott, R. Fritzen, W. A. Scherbaum
Dept. of Endocrinology, Heinrich-Heine-University, Duesseldorf, Germany
Vitamin D is essential for bone metabolism and calcium homeostasis. Osteomalacia is a rare disease in a western population due to a balanced food intake and sufficient exposure of the skin to sunlight.
We analyzed the data from our outpatient clinic retrospectively, and looked for patients with classic features of osteomalacia: i.e. general bone and muscle pain, decreased calcium and vitamin D levels, elevated alkaline phosphatase, increased urinary excretion of pyridinoline crosslinks and a low bone mineral density measured by dual energy X-ray absorptiometry. 25 patients met these criteria during a period of five years. If the diagnosis of osteomalacia was established, all patients underwent follow-up visits after one year of treatment with vitamin D and calcium.
18 of these patients were immigrants from the Middle East and 7 patients have been born and raised in Germany. The mean age (42±14.3 years) of the immigrants was significantly lower than the mean age of the german patients (72±18 years). Compared to an age- and sex- matched control group, alkaline phosphatase and urinary pyridinoline crosslink excretion was significantly (p<0.001) increased, while serum calcium and vitamin D levels were significantly decreased (p<0.001). Bone mineral density was significantly lower (p<0.001) in patients with osteomalacia than in controls. One year of treatment resulted in a normalisation of blood and urine parameters in nearly all patients and an dramatic increase in bone mineral density when compared to basal values.
Osteomalacia is found to be rare in Germany and is more frequently in older patients. Due to different habits in food intake and espicially due to a insufficient exposure of the skin to sunlight, osteomalacia is more common in immigrants from the middle east. Common practitioners should be aware of this problem and should inform this group of people to avoid harmful consequences for bone metabolism and bone mineral density.
BIOCHEMICAL MARKERS AND BONE HISTOLOGY IN ASIAN PATIENTS WITH VITAMIN D DEFICIENCY
S. J. Iqbal1*, I. M. S. Kaddam1, A. Fletcher2, H. McKay2, T. Davies1
1Department of Chemical Pathology, Leicester Royal Infirmary, Leicester, UK
2Department of Histopathology, Leicester Royal Infirmary, Leicester, UK
An excess of unmineralised (osteoid) bone tissue on biopsy samples is the "gold" standard for diagnosis of osteomalacia. Bone biopsy has disadvantages so we compared biochemical measures with bone histology in Asian patients with "nutritional" vitamin D deficiency.
15 females aged 33-91 years and 4 males aged 54-96 years were studied. Diagnosis of osteomalacia was made on clinical, biochemical, radiological and histological findings. BALP was measured by lectin precipitation, BGP by RIA, otherwise standard methods were used.
Results in mean and (SD). Adjusted calcium 2.21 mmol/l (0.22), PO4, 0.91 mmol/l (0.25), TALP 373 (331), BALP 268 (267), BGP 13.7 (6.8), osteoid % 11.7 (14.9). Correlation (r), of osteoid % were: adj calcium - 0.43 (ns), PO4 - 0.46**, TALP 0.85*, BALP 0.80*, BGP 0.27 (ns). (P<0.001* P<0.05**).
TALP and BALP were the best individual predictors of osteoid %. Stepwise regression showed best overall osteoid % predictors were TALP and BGP, (r=0.885, P<0.01). Osteoid % = (0.0455 x TALP) - (0.689 x BGP) + 4.18. Abnormal levels of TALP and BGP can be used to predict the presence of histological osteomalacia.
ADVERSE EFFECTS ON BONE MINERAL DENSITY IN PATIENTS WITH ANOREXIA NERVOSA
M. L. Fernandez-Soto*, M. Quesada, F. J. Gomez, V. Dolz, M. De La Higuera, A. Gonzalez, F. Escobar-Jimenez
Eating Disorders Unit, Endocrine Department, University Hospital San Cecilio
Adverse effects on bone mineral density (BMD)has been reported to occur in patients with anorexia nervosa (AN). Nutritional and hormonal factors have been implicated.
AIMS: To assess BMD in AN and the relationship with anthropometric, biochemical and hormonal parameters.
SUBJECTS and METHODS: We recruited 47 women who met DMS-IV criteria for AN. Mean age(±SD):22±6.5 yr.BMI:16.8±2.6Kg/m2. Age and sex-matched normoweight was used as control group. BMD was measured at the lumbar spine (LS) and three upper femoral sites: neck(N), trochanter(T)and Ward´s triangle(WT)by DEXA Hologic QDR 1000. Anthropometric (weight,BMI), biochemical (albumin, pealbumin, transferrin, retinol binding protein) and sex hormones were evaluated.
RESULTS: BMD Z-score was significantly decreased in AN versus control at LS(-1.72±1.09, p<0.0001), at N(-1.22±1.11, p<0.0001) at T(-1.05±1.00, p<0.0001) and at WT(-0.67±1.13, p<0.01). A linear correlation was found between BMD(g/ cm2) at LS(r=0.57, p<0.0001), at N (r=0.62, p<0.0001), at T(r=0.65, p<0.0001) with weight and BMI. No relationship was found between biochemical and hormonal parameters with BMD.
CONCLUSIONS: The AN patients had a decreased BMD at all the studied sites compared with a matched control population. The LS is the location more affected. There is a close relationship between the lost of weight and the loss of BMD in AN patients.
THE EFFECT OF CALCIUM & VITAMIN D SUPPLEMENTATION IN INDO-ASIANS SUFFERING FROM HYPOVITAMINOSIS D WITH OR WITHOUT SECONDARY HYPERPARATHYROIDISM
E. Serhan1*, M. R. Holland2
1Department of Rheumatology, New Cross Hospital, Wolverhampton, UK
2Department of Cinical Chemistry, New Cross Hospital, Wolverhampton, UK
Background: High prevalence of hypovitaminosis D (HD) and associated secondary hyperparathyroidism (HD-SHPT) amongst Indo-Asians is now well documented. Calcium/vitamin D supplementation in vitamin D deplete elderly subjects has been shown to inhibit bone resorption primarily by suppression of parathyroid hormone (PTH) levels. We know of no studies which have assessed the effect of supplementation therapy on Indo-Asians who develop vitamin D deficiency.
Methods & patients: A total of 84 patients aged 51±13 from Rheumatology clinic, 90.5% females (n=76) were recruited to the study. 56(66.7%) had HD with mean age 49±12 and 28(33.3%) had HD-SHPT aged 56±12. None had renal impairment, malabsorption and none were on anti-convulsants. Only 5 had inflammatory arthritis, the rest complained of non-specific aches and pains. All were commenced on calcium 1.25g + cholecalciferol 400units b.d for 8 weeks, followed by o.d regime. After six months urea, electrolytes, bone profile, 25-OH-vitamin D and PTH levels were re-checked.
Statistics: The groups were compared using the Mann Whitney and unpaired t tests. Results were considered significant at p<= 0.025 (one sided test).
Results: Reduction in total alkaline phosphatase levels before and after 6 months of treatment was significant only in the whole group (238±400 v 179±95 NR=80-330 IU/l p<0.001). 25-OH-vitamin D levels (NR=8.0-60.0ug/) rose significantly in the whole group (4.2±2.1 v 14.3±8.3 l p<0.001), including the HD (4.5±2 v 14.3±9 p<0.001) and HD-SHPT (3.5±2.7 v 14±7 p<0.001) patients after treatment. Similarly PTH levels (NR=12-72ng/l) were significantly suppressed in the whole group, (79±108 v 60±84 p<0.019) and in HD-SHPT patients despite the discovery of non-compliance with therapy in 3 patients (158±159 v 106±133 p<0.001), but not in HD group (39±15 v 37±19 p<0.269). There was significant rise in calcium levels (NR=2.00-2.60mmol/l); whole group (2.35±0.12 v 2.43±0.12 p<0.001), HD-SHPT patients (2.33±0.12 v 2.44±0.15 p<0.005) and HD patients (2.37±0.12 v 2.44±0.10 p<0.001).
Conclusion: The ability of patients to respond to calcium and vitamin D supplementation with suppressed PTH and an increase in 25-OH-vitamin D and calcium levels suggest that a reduction of vitamin D receptors is not an important factor in the development of hypovitaminosis D in this ethnic group of patients.
BIOCHEMICAL MEASURES AND BONE MINERAL DENSITY IN ASIAN PATIENTS WITH SEVERE VITAMIN D DEFICIENCY
S. J. Iqbal*, T. D. Davies, S. Muhlbayer, G. McHugh, O. Badawy
Department of Chemical Pathology, Leicester Royal Infirmary, Leicester, UK
Vitamin D deficiency is well described in Asians in the UK. Leicester City has a high proportion of south-east Asian Indians, 23.7% of a total population of 266,473. We see cases of severe clinical vitamin D deficiency with ensuing osteomalacia which can result in a low bone mineral density (BMD). We examined biochemical measures and BMD (gms/cm) at the lumbar spine -L2-L4- (BMD:LS) and femoral BMD;FN)
In 34 Asians (m;8, premenopausal f;26, age range 20-58 years) adjusted calcium mmol/l (CAL) phosphate mmol/l (PO4) alkaline phosphatase iu/l (TALP)(nr 40-130) were measured routinely, parathormone (nr 1.6 - 7.6 pmol/l) (PTH) by IRMA and 25-hydroxy vitamin D (nr 10-40 ug/l)(25(OH)VitD) by RIA. BMD was measured by Lunar Expert.
Results in mean and (sd):BMD;LS 0.89 (0.17),BMD;FN 0.70 (0.15),CAL 2.05(0.23),PO4 0.94 (0.25),TALP 234(176) and PTH 33(22).
Correlation coefficient (r)(n=26) of BMD:LS and BMD:FN versus CAL; -020, -0.11, PO4; -0.21, -0.01, TALP; -0.42*, -0.19 and PTH; -0.30, -0.30 respectively. All had low undectable 25(OH)VitD. (*P<0.05).
TALP appears to be the best predictor of low spinal BMD in vitamin D deficiency with ostoemalacia.
LOW PHOSPHATE DIET ALTERS MRNA GENE EXPRESSION IN THE HYPOTHALAMO-PITUITARY COMPLEX OF THE RAT
M. H. Meyer1*, B. Louie2, S. E. Mulroney2, M. Levi3, R. A. Meyer1
1Carolinas Medical Center, Charlotte, NC USA
2Georgetown Univ. Sch. Med., Washington, DC USA
3Univ. Texas Health Sci. Ctr., Dallas, TX USA
The phosphate-regulating hormone remains elusive. Mulroney et al. (Faseb J. 14: A659, 2000) have found that infusion of phosphate into the third ventricle of the brains of P-deprived rats resulted in the down-regulation of the type II sodium-phosphate cotransporter (NaPi2) protein in both the hypothalamus and the kidney. This suggestion of a functional link between the two organs led us to search for other hypothalamic genes sensitive to change in phosphate levels. Male Wistar rats (264±4 g) were fed a normal (n=3) or low phosphate (n=4) diet for five days. The pituitary and hypothalamus were combined and rapidly frozen. Total RNA was extracted, and aliquots were pooled to give a control and a low-P-diet sample. These two pools were processed by the Affymetrix protocol to cRNA. Each cRNA was hybridized to an Affymetrix Rat U34A DNA microarray containing 8,799 full-length genes, clones and EST sequences (Research Genetics, Huntsville, AL). 4,855 genes were scored as absent in the control and unchanged in the low P sample. Of the remaining 3,944 expressed genes, 17 were scored as up-regulated 2 fold or more and 33 down-regulated 2 fold or more in the low P sample. NaPi2 was scored as present in the control and up-regulated 1.8 fold in the low P sample. Known pituitary hormones were scored as present in the control and unchanged in the low P sample. To confirm these results, primers were constructed for the altered genes, and mRNA expression measured by reverse transcription - polymerase chain reaction (RT-PCR) in the mRNA from the individual animals. Seven of these genes did not change significantly upon assay by RT-PCR. Two genes, both EST sequences, AI014091 (2.2 fold increase, P<0.001, resembles mouse Mrg1 gene) and AA893172 (1.6 fold increase, P<0.02, no known homology), were up-regulated in the rats fed the low phosphate diet. In conclusion, low phosphate diet results in a change in the mRNA expression of specific genes in the hypothalamo-pituitary complex of rats. Future studies will elucidate the role of these genes in phosphate homeostasis.
ENERGY AND NUTRIENTS INTAKE IN A GROUP OF PSYCHOLOGICAL DISABLED PEOPLE
L. Pérez Gallardo*, Y. García Pérez, J. Gil Mateo
Bioquímica y Biología Molecular, Universidad de Valladolid, Spain
The objective of this work was to know the feeding habits and value the ingestion of nutrients concerning the osseus mineral metabolism in a group of students of a Public Centre for psychological disabled people in Soria. For this project, 34 students, of both sexes, (16 girls and 18 boys) between 5 and 20 years-old, carried out a dietetic opinion poll for seven days. This public poll has been elaborated by the Nutrition Institute of Granada University. The analysis of the survey was done using a statistic programme "FEEDING AND HEALTH". Anthropometric facts were also picked up and were used to calculate the Corporal Mass Index (CMI) and thus, we classified as obese people, those whose values were similar or over 30. The distribution of the ration of energy and the percentage (%) about the recommended ingestion (RI) of nutrients related to the osseus mineral metabolism in the people who took part in the poll, are showed in the following table.
In the elaborated patterns, it can’t be seen risky factors, either exogenous or endogenous, except epilepsy in 30% of the polled among them, 50% were taking more than one antiepilectic medicine. If we take into account epilepsy and the anticonvulsion therapy above all, multiple, as factors that cause osteoporosis and/or osteomalacie and that the taking of Vitamin D is less than the recommended ingestion and that we haven’t found any recommendation about supplementary contributions of Calcium and vitamin D, we consider that the results of this survey should be taken into account for next medical records of prevention and control of osteoporosis in specific groups.
| Energy (Kcal/day) |
Proteins (%RI) | Lipids (%RI) |
Glucides (%RI) |
Ca (%RI) | Mg (%RI) | Vit.D (%RI) |
| 2424±292 | 137±24 | 149±19 | 137±10 | 142±25 | 93±13 | 43±16 |
| Mean±SD of 34 values | ||||||
NUTRITIONAL FACTORS ASSOCIATED WITH BONE MASS OF DIFFERENT SKELETAL SITES IN POSTMENOPAUSAL WOMEN
J. Z. Ilich*, A. R. Brownbill, C. Lindsey, E. H. Mulrenan
University of Connecticut
Nutrition is important modifiable factor in bone health. Besides calcium(Ca) that has been studied extensively, other nutrients such as protein, magnesium(Mg), phosphorus(P), zinc(Zn), copper(Cu), iron(Fe), folate, vitamins D, A, C, and K are required for normal bone metabolism, while other compounds not usually categorized as nutrients (caffeine, alcohol, fiber) may also impact bone health. Many nutrients are co-dependent and at the same time interact with genetic and environmental factors. The complexity of the interactions is probably the reason why there are inconsistent findings regarding their contribution in bone health. The purpose of this study was to evaluate the effect of the above nutrients on bone mass in several skeletal sites.
The subjects were 90 healthy, Caucasian, postmenopausal women, with mean±SD for weight(WT), height(HT) and BMI of 67.9±11.5kg, 161.4±6.6cm, and 26.1±3.9kg/m2, respectively. Bone mass of the whole body, forearm, spine, and femur (neck, trochanter, Ward’s and total) was measured by DXA (Lunar). Dietary intake was assessed by 3-day records, after the subjects have been individually instructed. The diet was analyzed with nutritional package, Food Processor (ESHA Research, Salem, OR), and the mean daily intake for calories and all other macro- and micro-nutrients was calculated. The vitamin and/or mineral supplements were also included in analysis.
The forward stepwise regression models with each of the bone variable as dependent and all food components as independent ones (including total calories, WT and HT to account for different body size) were developed. The best model for total body BMD, adjusted R2=18.1%, was with WT, Ca, folate, Fe, and Mg (p less than 0.05 for each); for lumbar spine BMD, R2=21.1%, with WT, Ca, P, Mg, Zn, and alcohol (p less than 0.05); for total femur BMC, R2=44.5%, with WT, vitamin K, Fe, Mg (p less than 0.05); and for 33% forearm (radius and ulna) BMD, R2=15.0%, with Ca, calories and folate (p less than 0.05). Similar relationships were found with other sites in femur and forearm, as well as with BMC of the above skeletal sites. Based on our analyses, Ca, Fe, and Mg appeared as most consistently related to bone mass. Unraveling the interaction between different nutritional factors and their influence on bone mass will help in understanding the complexity of osteoporosis and its prevention.
BONE CHANGES IN AROMATASE OVER-EXPRESSING TRANSGENIC MICE
Z. Q. Peng*, X. D. Li, S. Mäkelä, M. Poutanen, H. K. Väänänen
University of Turku, Finland
Estrogen is an essential hormone for bone metabolism and maintaining bone mass. Aromatization of androgens is an important source for estrogen production in the body. In order to understand the skeletal response to estrogen produced by aromatase, we investigated the bone changes in aromatase over-expressing transgenic (AROM+) mice. In the age of 40 days, body weights of AROM+ mice were lower compared to wild type (WT) mice in both male and female. The lengths of tibia and femur were significantly shorter in AROM+ than in wild type animals (p<0.001 in male; p<0.05 in female), but the ash weight of both bones were not different between groups (n=9-15).
Peripheral Quantitative Computed Tomography (pQCT) measured parameters showed that AROM+ animals had a much higher trabecular bone density in the proximal tibia compared with the WT animals. The cross sectional area of cortical bone in tibia was not different between groups, but the tissue area and the polar moment of inertia were significantly higher in WT animals. Histomorphometric data was consistent with the pQCT measurements, and further showed that AROM+ mice had a lower longitudinal growth rate of bone and also a lower periosteal bone formation rate. All the data showed that effect of the aromatase over-expression is much pronounced in male. These results suggest that excess estrogen synthesis by aromatase can increase trabecular bone volume, and decrease the longitudinal and periosteal bone growth of young mice. Since mice over-expressing aromatase have high circulating levels of estradiol, the role of local production of estrogen in bone remains to be studied using tissue specific over expression of aromatase.
A COMMON FACTOR RAISES BLOOD PRESSURE AND PROTECTS AGAINST FRACTURES AMONGST MIDDLE-AGED AND ELDERLY MEN
G. Sigurdsson1,2*, K. Siggeirsdottir2, B. Y. Jonsson3, B. Mogensen4, H. Jonsson jr4
1Department of Medicine, Landspitali, University Hospital, Reykjavik, Iceland
2Icelandic Heart Association, Reykjavik, Iceland
3Akranes Hospital, Akranes, Iceland
4Orthopaedic Department, University Hospital, Reykjavik, Iceland
Introduction: Some studies have suggested an association between bone mineral density and hypertension which has been explained by the effect of drugs, especially thiazide diuretics, although this has been noted also amongst other hypertensive groups. We have evaluated the relationship between blood pressure and future fracture incidence amongst Icelandic men, with or without antihypertensive therapy.
Study group and methods: A population based random group of 4394 men from the Reykjavik area, participating in a prospective heart study 1968-1972. Mean age at entry was 48.2 years (range 33-64 years) and the mean follow-up time was 21 years. The participants answered a detailed questionnaire on health, medications and social status and anthropometric characteristics were measured including blood pressure at entry. All fractures occurring after the enrollment into the study until January 1, 1997 were registered. Pathological fractures due to malignancies were excluded.
Results: In a multivariate Poisson regression analysis including such factors as body mass index, smoking and physical activity, systolic blood pressure was an independent protective factor for future fractures, the risk was reduced by 8% for each 10 mmHg increment in systolic blood pressure. This association remained after excluding the group taking antihypertensive drugs at entry. The risk of fractures was on the other hand increased by 1% for each 1 cm in body height, and by smoking 30%, but physical activity decreased the risk by 15%.
Conclusion: This study suggests a common factor raising blood pressure and increasing bone strength amongst middle-aged and elderly men.
EFFECTS OF MELATONIN TREATMENT ON BONE TISSUE OF ORCHIDECTOMIZED RATS
D. Bertoncello*, K. O. Nonaka
Federal University of São Carlos - DCF, São Paulo, Brazil
The ability of the pineal gland to produce melatonin declines significantly with age in many animals as well as in man. It was showed that melatonin stimulates the synthesis of type I collagen, osteoblast differentiation and, mineralization of the matrix in human bone cells in vitro. The orchidectomized rat model has been considered as an animal model for androgen-induced bone loss in men. The aim of this investigation was to evaluate the effect of melatonin treatment on the bone of orchidectomized rat. The study used 24 male rats divided into the following 3 groups, each comprising 8 animals: intact, orchidectomized-treated with saline (injected with saline sc during 8 weeks, 6 days/week) and orchidectomized-treated with melatonin (200 ug/kg sc during 8 weeks, 6 days/week). Orchidectomy (Orchx) was performed at 16 weeks of age, one day prior to the beginning of the treatment. Biomechanical and physical parameters analyses were performed on the right femur. The femur calcium and phosphorus contents were also analyzed, as well as study by scanning electron microscopy from left femur. Orchx reduced the femur weight/length index, bone volume, phosphorus content, maximum load and bone quality. The melatonin treatment had the tendency (p=0,065) to increase the bone volume of orchx rats and did not modify the maximum load in these animals. The femur calcium and phosphorus contents were increased with the melatonin treatment in the castrated rats. When the normalized maximum strength was calculated, the orchx mel group showed no statistical difference from the intact control group. These results were corroborated by scanning electron microscopy. In conclusion, this study has shown for the first time that melatonin has a protective effect on the osteopenic action of androgen deficiency in rats.
| Intact | Orchx Saline | Orchx Melatonin | |
| Body weight gain (g) | 87.38+-16.76 | 65.75+-11.04 | 19.88+-15.07* |
| Femur length (mm) | 39.91+-0.634 | 39.55+-0.257 | 38.89+-0.351 |
| Femur weight (mg) | 917.40+-35.99 | 837.05+-20.99 | 889.71+-20.51 |
| Femur weight/length index (mm/mg) | 22.97+-0.749 | 21.15+-0.422# | 22.88+-0.493@ |
| Femur volume (mm3) | 0.550+-0.027 | 0.445+-0.016# | 0.484+-0.007# |
| Femur ash weight (mg) | 430.38+-20.03 | 403.51+-3.659 | 399.28+-13.814 |
| Calcium content (mg/mg) | 0.67+-0.08 | 0.62+-0.07+ | 0.75+-0.12@ |
| Phosphorus content (mg/mg) | 0.188+-0.006 | 0.171+-0.002# | 0.196+-0.006@ |
| n=8; p<0.05 *from Intact and Orchx saline; # from Intact; @ from Orchx saline; +p=0.065 from Intact | |||
THE MSP1 POLYMORPHISM OF COLLAGEN TYPE I ALPHA 2 GENE IS NOT RELATED TO THE DEVELOPMENT OF OSTEOPOROSIS IN MEN: PRELIMINARY RESULTS
I. Ros*, L. Alvarez, P. Peris, N. Guañabens, A. Monegal, T. Ferro, F. Pons, D. Cerda, A. Ballesta, J.Muñoz-Gómez
Hospital Clinic, University of Barcelona, Spain
Background: The genes encoding collagen type I a1 (COLIA1) and a2 (COLIA2) are excellent candidates for genetic regulation of bone density, since osteogenesis imperfecta has been associated with mutations of the coding regions of these genes. Thus, a Sp1 COLIA1 polymorphism has been recently associated with the development of osteoporosis in both genders. However, the influence of COLIA2 polymorphism in bone mass is not known.
Aims: To analyze the distribution of Msp1 polymorphism of COLIA2 in men with idiopathic osteoporosis and to compare it with the healthy population.
Patients and methods: 44 men with idiopathic osteoporosis aged 31 to 77 (years mean 52.8±1.7 years) were included in the study. Osteoporosis was defined by the presence of atraumatic vertebral fractures and/or lumbar or femoral bone mineral density (BMD) <2 Z-score. The COLIA2 genotypes (NN, Nn, nn) were assessed using the polymerase chain reaction (PCR) and digestion with the restriction enzyme Msp1 of amplified DNA. BMD of the lumbar spine and femur were measured by dual X-ray absorptiometry (lunar DPX-L) and X-rays of spine were obtained for all patients. Vertebral fracture was defined as a reduction <20% in the anterior, middle or posterior height of the vertebral body. The results were compared with a control group of 64 men of similar age.
Results: Patients with idiopathic osteoporosis had similar allele and genotype frequencies than control group (allele frequencies in patients: N 89%, n 11%; controls: N 92%, n 8%, p=NS) (genotype frequencies in patients: 80% NN, 18% Nn, 2% nn, controls: 84% NN, 16% Nn, 0% nn, p=NS).
Patients with osteoporosis did not show significant differences in BMD between genotypes (Lumbar BMD in NN patients: 0.88±0.0 g/cm2; Lumbar BMD in Nn+nn 0.88±0.0 g/cm2, p=NS) (Femoral BMD in NN patients: 0.80±0.0 g/cm2; Femoral BMD in Nn+nn 0.85±0.0 g/cm2, p=NS).
Conclusions: The results of this study suggest that the Msp1 polymorphism in the collagen type I alpha 2 gene is not associated with the development of idiopathic osteoporosis in men.
CAUSES OF OSTEOPOROSIS IN MEN WITH HIP FRACTURES
D. N. Edis1*, B. Erbas2, S. Yeung3, C. Poon3, P. R. Ebeling3
1Dept Surgery, University of Melbourne, Australia
2Dept General Practice and Public Health, University of Melbourne, Australia
3Dept. Diabetes and Endocrinology, University of Melbourne, Royal Melbourne Hospital, Australia
By 2010, 30% of all hip fractures will occur in men. While vertebral fractures are more common in men with the lowest serum oestradiol concentrations, it is not known whether serum oestradiol concentrations are low in men with hip fractures. We assessed 32 men, aged (age±SD) 76±14 yrs, with femoral neck fractures after minimal trauma and 18 control men with hip osteoarthritis (OA), aged 67±10 yrs to determine secondary causes for hip fractures in men and to define differences in bone and mineral metabolism. We assessed environmental factors; biochemical bone markers; serum sex and calciotrophic hormone concentrations and bone mineral density (BMD) at the spine (LS) and proximal femur (FN), measured by DXA. Bone biopsies were performed near the fracture site.
Twenty-three men (72%) in the hip fracture group had secondary causes for osteoporosis: low serum testosterone (14); chronic renal impairment (Cr>0.15 mmol/L) (10); current use of glucocorticoids (* 5 mg/d prednisolone) (3); low serum 25(OH) vitamin D (7); rheumatoid arthritis (3); and ethanol overuse (4). When compared with controls, men with hip fractures had lower FN-BMD (p=0.0007); lower free androgen index (p=0.006); higher oestradiol (p=0.01); lower serum IGF-I (p=0.007); higher PTH (p=0.003); and higher urine deoxypyridinoline (D-Pyr) (p=0.004). There were no differences in dehydroepiandosterone sulphate (DHEAS). Multiple regression analysis with age correction showed men with hip fractures had lower FN-BMD (p=0.002); lower serum IGF-I (p=0.02); higher PTH (p=0.008) and higher urine D-Pyr (p=0.02) than men with OA. No age-independent differences between groups were seen for serum sex hormones, DHEAS, 25(OH) vitamin D or osteocalcin.
In conclusion, secondary causes for osteoporosis are present in the majority of men with hip fracture. Bone resorption rates and serum PTH are increased while IGF-I levels are decreased compared with controls, while age-related changes in sex hormones, particularly testosterone, also contribute. Low serum oestradiol concentrations may contribute less to hip fractures than to vertebral fractures in men.
COLLAGEN TYPE I ALPHA1 SP1 BINDING SITE POLYMORPHISM AND THE RISK OF OSTEOPOROSIS IN MEN
A. Rogers1*, D. Fatayergi1, Y. M. Henry1, J. A. Sorrell2, R. Eastell1
1Bone Metabolism Group, University of Sheffield, UK
2Division of Molecular and Genetic Medicine, University of Sheffield, UK
Recent studies have shown that a polymorphic Sp1 binding site in the collagen type I alpha1 (COLIA1) gene is associated with bone density and vertebral fracture in postmenopausal women. However few studies have considered the importance of this polymorphism to the risk of osteoporosis in men. In this study we examine the association between the COLIA1 polymorphism and bone density and bone turnover in a population of healthy Caucasian men.
Subjects were 178 men, ages 20 to 79 years (approximately 30 per decade, mean 50 years). Bone mineral density was measured at total body (TBBMD), greater trochanter (TROCHBMD), femoral neck (FNBMD) and lumbar spine (LSBMD) by DXA (Lunar DPX). Procollagen propeptide of type I collagen (PINP) was measured by RIA (Orion Diagnostica) and the cross-linked N-telopeptide of type I collagen (NTX) was measured by ELISA (Osteomark). COLIA1 genotypes were determined using an ABI PrismTM 7200 Sequence detection system. BMD and bone marker measurements were adjusted for age and expressed as z scores. Comparisons between genotypes (SS vs Ss and ss) were made using a 2-sample t test.
The frequency of genotypes was SS 65%, Ss 32%, ss 3% and was in Hardy-Weinberg equilibrium. BMD was higher in the SS genotype compared to Ss and ss at all sites. There were no differences in PINP and NTX levels between genotypes (table).
We conclude that there is an association between bone density and COLIA1 genotype in men, and that this is greater in the region of the hip. The underlying molecular and cellular events leading to this association remain unclear since we found no association between type I collagen markers of bone turnover and genotype. We suggest that the relationship between bone density and COLIA1 genotype may arise from differences in peak bone mass.
| SS | Ss and ss | p | |
| TBBMD | 0.09 (0.09) | -0.16 (0.13) | 0.11 |
| *TROCHBMD | 0.12 (0.08) | -0.23 (0.14) | 0.02 |
| *FNBMD | 0.10 (0.08) | -0.21 (0.14) | 0.05 |
| LSBMD | 0.10 (0.08) | -0.19 (0.14) | 0.07 |
| NTX | 0.05 (0.10) | -0.10 (0.10) | 0.54 |
| PINP | -0.37 (0.09) | 0.08 (0.14) | 0.48 |
| Values are mean z score (SE), * p is significant at the 95% confidence interval | |||
TRABECULAR BONE MASS AND BONE FORMATION ARE PRESERVED AFTER MECHANICAL UNLOADING IN P53 KNOCKOUT MICE
A. Sakai1*, T. Sakata1, R. Okazaki2, N. Kunugita3, T. Norimura2, T. Nakamura1
1Department of Orthopaedic Surgery, University of Occupational and Environmental Health, Kitakyushu, Japan
2Department of Radiation Biology and Health, University of Occupational and Environmental Health, Kitakyushu, Japan
3Department of Health Information Science, University of Occupational and Environmental Health, Kitakyushu, Japan
To clarify the hypothesis that mechanical unloading facilitates signaling of p53, an important modulator of cell cycling and apoptosis, in bone marrow cells, thereby reduces trabecular bone volume, we performed the histomorphometric analyses and bone marrow cell cultures in tail-suspended p53 knockout mice. Wild-type mice [p53(+/+)] and p53 knockout mice [p53(-/-)], 8-week-old male, were assigned to 4 groups as follows, after acclimatization for one week: p53(+/+)+ground control (GC), p53(+/+)+tail-suspension (TS), p53(-/-)+GC, and p53(-/-)+TS. Bilateral tibial samples were used for analysis.
The histomorphometric parameters of trabecular structure, formation and resorption did not differ between the p53(-/-)+GC and p53(+/+)+GC groups. Trabecular bone volume in p53(+/+)+TS mice was significantly reduced to 45% of that in p53(+/+)+GC group after 1 week of TS. In contrast, bone volume in p53(-/-)+TS mice was preserved at the same level as that in the p53(-/-)+GC group. The bone formation rate was significantly reduced in p53(+/+)+TS, but not in p53(-/-)+TS mice.
In the bone marrow cell culture, the numbers of alkaline phosphatase (ALP)-positive colony-forming units-fibroblastic (CFU-f) and mineralized nodules were significantly reduced in p53(+/+)+TS, but not p53(-/-)+TS. [3H]Thymidine incorporation into bone marrow cells was higher in p53(-/-) mice than in p53(+/+) mice, independent of mechanical loading or unloading. Flow cytometric cell cycle analysis revealed that unloading significantly increased the percentage of hypoploid bone marrow cells in p53(+/+) mice relative to that in p53(+/+)+GC mice, but there was no significant difference in ploidy between p53(-/-)+TS and p53(-/-)+GC mice. mRNA expression of p53 and p21 was enhanced after TS in bone marrow cells from p53(+/+) mice.
These data demonstrated that trabecular bone mass and bone formation were preserved after TS in p53(-/-) mice, closely associated with ALP-positive CFU-f and mineralized nodule formation in marrow cultures obtained from tibiae of p53(-/-) mice. Bone loss due to mechanical unloading may be related to facilitation of intracellular p53-p21 signaling.
DIFFERENCES OF CALCANEAL ULTRASONOMETRY BETWEEN PHYSICAL EDUCATION AND SPORT SCHOOL STUDENTS AND MEDICAL FACULTY STUDENTS
B. Durmaz1,2*, B. Ozcaldiran2
1Ege University Medical Faculty, Physical Therapy and Rehabilitation Department, Turkey
2Ege University, Physical Education and Sport School, Turkey
The aim of this study was to investigate the differences of calcaneal ultrasonometry between two groups of university students.
First Group consisted of Physical Education and Sport School Students (n=50) and the Second Group consisted of Medical Faculty Students (n=65). All of them were male (ages 20-22, mean age 21.16 years). The first group had been training regularly and the second group was sedentary. The individuals had completed a questionaire form that was consisted all important risk factors. Ultrasonic measurements were performed using Sahara Clinical Bone Sonometer. Bone mineral density (BMD), speed of sound (SOS), broadband ultrasound attenuation (BUA) and quantitative ultrasound index (QUI) were measured by same physician. Differences between the two groups were estimated using Mann-Whitney U tests.
All ultrasonic measurements were higher in the first group (p<0.05). There were no significant differences between the two groups in the respect of weight, height and body mass index.
The results of this study emphasized the importance of the effect of athletic activities on bone mineral density.
6 MONTHS HIGH STRAIN EXERCISE RESULTS IN AUGMENTATION OF LEAN MUSCLE MASS AND BONE MASS AND DENSITY OF TIBIA IN POSTMENOPAUSAL OSTEOPENIC WOMEN
A. J. Kapsabelis1*, G. Skarantavos2, G. Prevena1, S. Mitakidis3, A. Gioni4, A. Galanos4, G. Lyritis4
1Prefecture of Keratsini
2Rheumatology Dept., Kat Hospital
3IKA Amfiali
4Laboratory for the Research of Musculoskeletal Diseases, University of Athens, Greece
Aim: To study the effect of high strain, group exercise in lean muscle mass, bone mass and geometry, in physical and functional fitness and psychological well-being of postmenopausal osteopenic women.
Methods: 56 postmenopausal women were randomly allocated into 2 groups: A (n=34, age: 60±11) and B (n=22, age: 62±10) and were subjected in laboratory tests of bone metabolism. Group A was subjected for 6 months in 3 times a week, 60 minute program of aerobic dancing, bench and rope jumping and resistance training. Group B (control) had had no exercise. All women at the beginning and at the end of the research completed a questionnaire on their physical and functional fitness and psychological well-being, were subjected in three tests of physical and functional fitness and in measurement of their left tibia by pQCT (Stratec 2000) with slices at 4%, 14%, 38% and 66% of the tibia length.
Results: No statistical differences were noted between groups at the beginning of the study. At the end the exercise group presented significant augmentation of lean muscle area (p=0.002), significant augmentation of total bone mass (p=0.029), total bone density (p=0.018) and subcortical bone mass (p=0.004) at the 4% slice, whereas the control group showed no differences. The control group experienced a significant loss of total bone mass at the 38% slice (p=0.029), whereas the exercise group maintained total bone mass (p>0.05).The exercise group reported a significant improvement of all the questionnaire’s parameters and tests (p<0.01), compared to the control group that reported no difference.
Conclusions: According to our results, a 6 months high strain exercise program in postmenopausal, osteopenic women results in: (1) Significant improvement of physical and functional fitness and psychological well-being.(2) Augmentation of lean muscle mass of the calf. (3) Augmentation of the total bone mass and bone density of distal tibia, mainly attributed to the subcortical bone. (4) Maintenance of cortical bone mass of mid-tibia.
THE EFFECT OF PHYSICAL EXERCISE ON INSULIN LIKE GROWTH-FACTOR AND IGFBP-3 LEVELS IN PATIENTS WITH OSTEOARTHRITIS AND OSTEOPOROSIS
H. Franck1*, F. Blum2
1Rheumazentrum Oberammergau
2University of Tübingen
IGF-1 and IGFBP-3 are known to influence bone turnover. The aim of our study was to examine the effect of physical exercise on insulin like growth-factor and IGFBP-3 levels in patients with osteoarthritis und osteoporosis.
Methods:
130 patients with osteoporosis (WHO-definition) (mean age 51.6±15 years) and 90 patients with lumbar spine syndrome (mean age 50.8±16 years) were included in the study. IGF-1 and IGFBP-3 were determined as described by Blum et al..
Patients performed a standarized physical exercise program. All patients with osteoporosis and osteoarthritis were included in a randomized open controlled trial into two arms one group I: classic physiotherapy, group II: weight bearing exercise.
Results:
Patients with osteoporosis presented with a significant increase of IGF-1 (121.8±37.2 µg/l vs 128.9±35 µg/l) after physical therapy. In contrast, patients with osteoarthritis didn't show a significant increase after physical therapy. There was no significant change in IGFBP-3 either.
Looking at different therapy strategies in patients with osteoporosis and patients with osteoarthritis group I didn't show any significant increase in IGF-1 (102±26 µg/l (r) 101.7±38 µg/l) in patients with osteoporosis and osteoarthritis (144±48 µg/l vs 145±47 µg/l). The same was evident for IGFBP-3 in patients with osteoporosis (2.7±0.46 µg/l vs 2.87±0.61 µg/l) and osteoarthritis (2.89±0.7 vs 3.12±0.61 µg/l). In contrast, in group II IGF-1 increase significantly from 103.8±25 µg/l to 120.0±27.6 µg/l (p>0.01) in patients with osteoporosis with no significant change in patients with degenerative disease (135.6±30 vs 135.2±33 µg/l). Correspondingly there was a significant increase in IGFBP-3 (2.91±0.18 vs 2.97±0.18 µg/l, p>0.0001).
Conclusion:
Weight bearing exercise leads to a significant increase of IGF-1 and IGFBP-3 in patients with osteoporosis.
EFFECT OF STEP MASTER AND NORDIC TRACK ON BIOCHEMICAL MARKERS OF BONE METABOLISM, BONE DENSITY, FITNESS, AND STRENGTH IN PREMENOPAUSAL WOMEN
M. Sinaki, J. Canvin*, P. Phillips, B. Clarke
Mayo Clinic, Rochester, MN, USA
The effects of regular weight-bearing exercise on parameters of bone health in premenopausal women are not well known. In the urban setting, indoor health clubs are common sites for exercise. Nordic Track (NT) and Step Master (SM) are two widely available devices used for weight-bearing exercise.
The objective of this pilot study was to determine whether participation in regular exercise using NT or SM can make a difference in bone mineral density (BMD) or markers of bone turnover in premenopausal women aged 29 - 45 years. These and other parameters were analyzed in 4 women using NT and 5 women using SM for at least 3 hours each week for 2 years, and 5 non-exercising control women.
All women were healthy, community dwelling individuals without prior history of disease or medication use known to affect bone metabolism, and all had normal 17B-estradiol levels. Differences between the exercise and control groups were analyzed by Wilcoxen ranked sum tests.
No significant differences were noted between exercise groups and controls with respect to age, height, BMD, calcium intake and metabolic bone markers. Significant differences were noted between exercise groups and controls with weight (NT, p=0.0022; SM, p=0.0181), BMI (NT, p=0.0022; SM, p=0.0165), PAS (NT, p=0.0037; SM, p=0.0004), % Body fat (NT, p=0.0127; SM, p=0.0054), and VO2max (NT, p=0.0049; SM, p=0.0011). There was also a significant difference with respect to bilateral hip extensor strength, between SM and controls (right, p=0.0305, left, p=0.0305). Of note was a significant difference between NT and SM with respect to grip strength (right, p=0.0028; left, p=0.0422).
Lack of differences in parameters of bone health between the exercise and control groups may have been due to the small number of subjects evaluated. However, it is also possible that physiologic mechanisms other than exercise are primarily responsible for maintenance of bone health in the premenopausal state. It is also possible that the level of exercise in the exercise groups was not sufficient enough to affect such a change.
We conclude that weight-bearing exercise helps to maintain body weight, aerobic fitness, and muscle strength, but not BMD in premenopausal women.
P485 T
Withdrawn
DIFFERENCES OF BONE DENSITY IN ATHLETES AND IN ANOREXIC PATIENTS ADOLESCENT FEMALES
A. Andreoli1*, U. Tarantino2, N. Candeloro1, M. Giampietro3, L. Promenzio2, A. De Lorenzo1
1Human Nutrition Unit, University of Rome "Tor Vergata", Rome, Italy
2Orthopaedic Department, University of Rome "Tor Vergata", Rome, Italy
3Institute of Sport Science, Rome, Italy
Bone mass acquired during adolescence and early adulthood may be one of the most important determination for the risk of osteoporosis later in life. Osteopenia is a frequent complication of anorexia nervosa in adolescent girls and occurs during a critical time in bone development. Moreover, in female athletes affected by eating disorders, premature osteoporotic fractures can appear.
Aim of the study was to examine Bone Mineral Density (BMD) and Bone Mineral Content (BMC) in female athletes, in patients with anorexia nervosa (AN) compared with age-height control groups.
Subjects and methods: Training history, Calcium intake, anthropometric measurements, body composition (BC), total bone mineral density and total bone mineral content were performed in 22 adolescent females, age 15.6 (sd 1.4) years, 8 gymnasts, 8 adolescent with anorexia nervosa and 6 age-height matched controls.
Training history was determined by questionnaires, Calcium intake by 7 d dietary record, body composition (lean mass and fat mass), BMD and BMC by dual-energy x-ray absorptiometry (DXA)
Results: Body weight and body mass index were significantly lower in athletes and anorectic patients against controls. BMD was not significantly (p<001) different between groups, however BMC was significantly lower (p<001) in AN and in athletes compared to control group, AN had the lowest value of BMC. Nevertheless, the athletes had higher BMC and Lean body mass compared to AN patients. An high correlation between lean mass and BMC were found in all groups.
Conclusion: the athletes and the AN had significantly lower BMC, Lean mass and Fat mass but not BMD. These results suggest that the effects of eating disorders (AN), particularly BMC, could be attenuated by physical activity. This fact being evidenced by high LMB of athletes which was highly correlated to BMD.
QUANTITATIVE ULTRASOUND AND OSTEOPOROSIS RISK FACTORS: EXERCISE IS INDEPENDENT OF BONE DENSITY
S. Dodin1,3*, C. Blanchet1,2,3, Y. Giguère4, F. Rousseau4, L. Turcot-Lemay1, M. Dumont5, D. Prud'homme2
1Unité de recherche en endocrinologie de la reproduction, Pavillon St-François D'Assise, CHUQ, Québec, Canada
2Laboratoire des Sciences de l'activité physique, Division Kinésiologie, Département de médecine sociale et préventive, Faculté de médecine, Université Laval, Québec, Canada
3Centre Ménopause Québec, Pavillon St-François D'Assise, CHUQ, Québec, Canada
4Unité de recherche en génétique humaine et moléculaire, Pavillon St-François D'Assise, CHUQ, Québec, Canada
5Département de médecine nucléaire, Pavillon St-François D'Assise, CHUQ, Québec, Canada
The purpose of the study was to assess the magnitude of the relationships between osteoporosis risk factors and bone index measured by a AchillesTM ultrasound bone densitometer (QUS) or dual-energy X-ray absorptiometry (DXA), in menopausal women.
We studied 856 French Canadian menopausal women. QUS parameters (broadband ultrasound attenuation (BUA), speed of sound (SOS), and Stiffness index (SI)) were measured at the right calcaneus. Bone mineral density (BMD; g/ cm2) at the lumbar spine and femoral neck was assessed DXA.
Our results show that in French Canadian menopausal women, age explained 15.4% of the variance in BMD at the lumbar spine, 9.4% at the femoral neck, and 15.9% of the stiffness index. Multivariate analyses revealed that physical activity levels, estrogen users, age, alcohol intake and weight are independent predictors of stiffness index of the calcaneum. At the femoral neck, an interaction with physical activity levels was found only in moderately active women. No significant difference was observed in adjusted lumbar spine or femoral neck BMD measured by DXA between active, moderately active and sedentary women. However, all QUS parameters (BUA, SOS, and stiffness) were significantly different according to physical activity levels. The association between physical activity levels and QUS parameters remains even after adjusting for lumbar spine BMD.
These results suggested that physical activity levels could influence QUS parameters, independently of BMD. The real impact of physical activity on QUS parameters should be evaluated in clinical trials. Whether QUS could be really measuring bone architecture and structure remains to be determine. Therefore, in future, the QUS technique could tone down the discrepancy observed between studies evaluating bone measurements and regular physical activity in postmenopausal women.
STOPPING TRAINING: EFFECT ON BROADBAND ULTRASOUND ATTENTUATION (BUA) IN PRE & POST-MENOPAUSAL USERS AND NON-USERS OF HRT
R. Donnelly*, N. M. Murphy, M. M. O'Rathaille
Waterford Institute of Technology, Waterford, Ireland
The purpose of the study was to monitor changes in BUA with exercise(9 months)& following 9 months of detraining.63peri- menopausal women were randomly chosen and assigned to exercise & control groups matched on a ratio of 2:1., with Menopausal & non-Menopausal, HRT & non-HRT subgroups. BUA measurements were taken at 0, 9 & 18 months (CubaClinical machine).The composition of the exercise regime included high impact boneloading, muscular strength & endurance work. The results indicate that BUA declined after cessation of the 9-month exercise intervention, and this happened both in the exercise and control groups. The declines in both groups, and in the group as a whole, were statistically significant (p<0.01). However, within group analysis showed that post- menopausal women, and non-users of HRT, had similar BUA responses, i.e.a significant gain in BUA over the exercise intervention period, a significant loss on cessation of exercise, leading, overall, to a non-significant change in BUA. On the other hand, pre-menopausal women, and women who were on HRT, also increased BUA over the initial 9 months of the study, but their BUA did not decline on cessation of exercise. There was a net gain in BUA in this group over the 18 months. The study suggests that women who were estrogen deplete (post-menopausal, or not on HRT) only maintained, or improved BUA when mechanical loading was applied, and lost the beneficial effect of loading on cessation of exercise. This is in keeping with Frost's mechanostat theory, i.e. in pre-menopausal women normal mechanical usage is sufficient to exceed the strain threshold for remodelling because estrogen levels are adequate. However, post-menopause, the setpoints of minimum effective strain increase, so women may need more mechanical force for conserving existing bone during this period(Frost,1991).
Reference:
Frost HM (1991). A new direction for osteoporosis research: a review and proposal. Bone, 12: 429-437.
MEASUREMENT OF ULTRASOUND TRANSMISSION VELOCITY ENABLES TO CONSIDER THE MECHANICAL PROPERTIES OF AN OSSEOUS IMPLANTATION SITE
P. H. Kann1*, B. Al-Nawas2, R. Brahm2, J. Vaterrodt2, K. A. Grötz2, W. Wagner2, J. Beyer1
1Clinic for Internal Medicine/Endocrinology and Metabolic Diseases, Johannes Gutenberg University Hospital, Mainz, Germany
2Clinic for Oral and Maxillofacial Surgery, Johannes Gutenberg University Hospital, Mainz, Germany
Non-invasive assessment of the mechanical properties of the skeleton by the measurement of ultrasound transmission velocity (UTV) is an established diagnostic tool in systemic metabolic osteopathies such as osteoporosis. It was the aim of this study to consider the usefulness of the measurement of UTV at the prospective implantation site in the jaw in order to estimate its mechanical properties in the planning of surgical treatment. Until now, the only available method to do this besides radiological techniques is to consider the subjective feeling while drilling the bone or performing torque measurement during implant insertion.
Seventeen mandibular and 17 iliac crest bones of freshly slaughtered pigs were used in this study. UTV was measured at the prospective host site using a DBMsonic-instrument (IGEA, Italy) with an ultrasound frequency of 1.25MHz. Surgical preparation of the implant bed was performed using a surgical handpiece that documented the maximum torque values used during cutting.
The UTV measured in the mandible (1777±172m/s) suggested a higher mechanical quality of this type of bone in comparison to the iliac crest (1611±69m/ s). Corresponding to these results, maximum torque at the mandible (16.5±6.7Ncm) was higher than at the iliac crest (9.0±8.8Ncm); the differences were statistically significant (p<0.05). Correlation coefficient between UTV and maximum torque was found to be r=0.50 (p<0.005).
These data suggest that UTV assessment at the prospective implantation site might enhance the planning of surgical treatment. Miniaturisation of the transducers will now allow the evaluation of this methodical approach in vivo.
FOREARM BONE MINERAL DENSITY IN PATIENTS WITH RHEUMATOID ARTHRITIS
J. Iwamoto1*, T. Takeda1, S. Ichimura2
1Keio University School of Medicine, Tokyo, Japan
2National Defense Medical College, Saitama, Japan
Rheumatoid arthritis (RA) is a common disease in women, and induces osteoporosis. Osteoporosis in RA has been reported to result from generalized bone loss: decreased physical activity, duration of disease, steroid use, and disease activity, and localized (periarticular) bone loss: immobility and bone resorbing cytokines. However, the etiology of bone loss in RA is multi-factorial, and the results in the previous studies are varied. Thus, it is hard to say that the pathogenesis of osteoporosis in RA is fully understood. The purpose of the present study was to determine the factors that affect forearm bone mineral density (BMD) in patients with RA. Eight hundred and thirty-nine postmenopausal women, aged 46-90 years, were enrolled for the study: 470 patients with RA (RA group) and 369 healthy controls (CON group). Forearm (distal radius) BMD was measured by DXA using a DTX-200 (Osteometer) in all the subjects. Original BMD and adjusted BMD by age, height, body weight, and years since menopause using stepwise regression analysis were compared between the two groups by ANOVA with Fisher's PLSD test. In the RA group, the correlations of original BMD with anatomic grade (Steinbrocker) in the wrist, functional class (Steinbrocker), duration of disease, modified health assessment questionnaire (HAQ) score in the upper and lower extremities, dose of steroid (prednisolone) use, c-reactive protein (CRP), erythrocyte sedimentation rate (ESR), and rheumatoid factor (RF) were examined by multiple regression analysis. Both original and adjusted BMD was significantly lower in the RA group than that in the CON group (both P<0.0001). In the RA group, multiple regression analysis showed that anatomic grade in the wrist, modified HAQ score in the upper extremity, and ESR were significantly correlated with BMD (P<0.001, P<0.0001, P<0.001, respectively), as were not functional class, duration of disease, dose of prednisolone use, modified HAQ score in the lower extremity, CRP, and RF. These findings suggest that forearm BMD was significantly lower in postmenopausal women with RA than that in healthy controls, and that disuse (anatomic grade) of the wrist, arm function, and disease activity appear to be significant determinants of forearm BMD in patients with RA.
BONE MINERAL DENSITY AND URINARY OSTEOPONTIN INCREASED WITH ESTROGEN THERAPY IN POSTMENOPAUSAL CALCIUM OXALATE STONE FORMERS
K. M. Kellum1,4*, J. S. Lindberg1, L. L. Hamm2, F. E. Husserl1, A. L. Burshell1, D. J. Kok3, J. B. Copley1, E. Reisen4, F. E. C. Cole1
1Ochsner Hospital, New Orleans, USA
2Tulane University, New Orleans, USA
3Erasmus Medical Centre, Rotterdam, Netherlands
4Louisiana State University, New Orleans, USA
Osteopontin (OPN) is a protein that has been found in many tissues, including the kidney. OPN is produced by osteoblasts and osteoclasts and is essential in normal bone formation and remodeling. It is unclear whether urinary osteopontin is derived from bone remodeling. Evidence supports estrogen involvement in bone remodeling.
This study examined the relationships between urinary OPN concentration and femoral neck bone mineral density (fnBMD) in postmenopausal calcium oxalate stone forming women (PMSF) (n=31), twelve on estrogen replacement therapy (+ert), and nineteen were not on estrogen treatment (-ert).Twenty-four hour urine samples were collected for determination of OPN by ELISA. Bone mineral density measurements (DEXA) of the hip done between 6 months before or 12 months after OPN measurement were examined. FnBMD was positively, linearly correlated (p<0.05) with OPN excretion for the 31 PMSF and for the (+ert) PMSF (p<0.05). In contrast, PMSF(-ert) fnBMD was not correlated. Under the influence of estrogen, osteoblasts are promoted and osteoclasts are inhibited.
Data in this report are consistent with a hypothesis that in the presence of estrogen, osteoblastic activity was promoted to produce increased urinary OPN and in the process build bone. In contrast, in the absence of estrogen, osteoclasts were promoted, urinary OPN was not increased, and in the process bone was resorbed.
URINARY cAMP SUPPRESSION TEST IN OSTEOPOROSIS
R. Tanakol1*, M. Akyýldýz1, A. Akköse2, B. Ömer2, S. Yarman1
1Endocrinology, Istanbul Faculty of Medicine, Istanbul, Turkey
2Biochemistry, Istanbul Faculty of Medicine, Istanbul, Turkey
The purpose of this investigation is to detect the value of calcium load test in the differentiation of various causes of hypercalciuria in the pathogenesis of osteoporosis and also the relationship between cAMP suppressibility and BMD. In patients with high-normal urinary calcium, 2-hr urine sample after an overnight fast and after 1 g of calcium by mouth were tested for calcium, PTH, urinary cyclic AMP (UcAMP) and creatinine. Group I consisted of 21 patients (age: 51±11yrs) with BMD<-2.5 SD T-score. Control group was composed of 12 healthy subjects (Group II, 47±9yrs) with BMD±1SD T-score. Serum concentrations of calcium, phosphorus, alkaline phosphatase, osteocalcin, 25 hydroxyvitamin D and daily urinary calcium excretion and hydroxyproline were not significantly different between the groups. In Group I, UcAMP increased from a fasting value of 3.4±1.4 nmol/100 ml GFR to 4.7±5.3 after 1g Ca load, while it decreased from 4.2±1.4 to 3.3±1.2 (p=0.04) in Group II (NS between groups). In group I, urinary Ca increased from a basal fasting level of 0.14 mg/mg Cr to 0.22±0.1 after oral Ca load. In Group II, basal fasting level of urinary Ca (0.07±0.04 mg/mg Cr) was significantly lower than that of group I (p=0.05), which increased to 0.19±0.09 (NS).
There were 12 cases with normal serum levels of PTH which suppressed after oral calcium load without associated suppression of UcAMP. The results suggested higher bone resorption in patients with osteoporosis despite the presence intact PTH levels within normal ranges. UcAMP may provide a more reliable index of parathyroid function than intact PTH in Ca loading test.
Five patients from Group I and 2 subjects from Group II had absorptive hypercalciuria. Renal hypercalciuria was found in 3 patients.
There is a possibility that there may be a link between calcium transport abnormalities in renal tubule and osteoporosis. Some women with osteoporosis may have some genetically determined abnormality in calcium handling both in renal tubule and bone.
THE BIOLOGY OF THE SOFT CALLUS IN LONG BONE FRACTURE REPAIR
J. L. Ford*, B. E. Scammell, D. Robinson
University of Nottingham, UK
Normal fracture healing in long bones involves the production of a soft cartilaginous callus which provides temporary mechanical support during the bone remodelling process. Although the removal of the soft callus is critical stage in fracture healing, much of the biology involved is not yet known.
In this study, a rabbit model was used to investigate cell and matrix removal from the soft callus over a 6 week period following bone fracture. The main aims were to establish whether cells in the soft callus die via apoptosis and whether matrix removal involves the action of proteolytic enzymes.
A standard tibial osteotomy was carried out on New Zealand white rabbits which were sacrificed 1 to 6 weeks after fracture. The bone was processed for either immunohistochemistry or transmission electron microscopy (TEM). Collagen type II and the receptor for a proteolytic enzyme called urokinase (uPAR) were co-localised whilst the TUNEL technique was used to identify apoptotic cells in the soft callus. Results were viewed on a confocal laser scanning microscope.
TUNEL results implied that apoptotic cells were only detected at very early time points, a number of weeks before the vast majority of cells in the soft callus disappear. TEM observations correlated with these results. This suggests that apoptosis is not the main mechanism of chondrocyte removal in the soft callus. Strong co-localisation of collagen type II and uPAR was detected in the soft callus within the first few weeks after fracture but neither were present by week 6. These results imply that protease activity is involved in the removal of the soft callus matrix and suggest that such proteolytic enzymes play a role in bone remodelling.
HIGH PREVALENCE OF VITAMIN D DEFICIENCY AND LOW BONE MASS IN PATIENTS WITH ADVANCED PERIPHERAL ARTERIAL OCCLUSIVE DISEASE
A. Fahrleitner1*, A. Obernosterer2, E. Pilger2, S. Kudlacek3, A. Hoffmann1, K. Weber1, B. Obermayer - Pietsch1, G. Leb1, H. Dobnig1
1Department of Internal Medicine, Div. of Endocrinology, Karl Franzens University, Graz
2Department of Internal Medicine, Div. of Angiology, Karl Franzens University, Graz
3Department of Internal Medicine, BHB, Vienna, Austria
Patients with advanced stages of peripheral arterial occlusive disease (PAOD) often are partially immobilized and lack sufficient sunlight-exposure. They frequently describe paresthesia, diffuse muscle or deep bone pain, arthralgia and muscle weakness, symptoms suggestive of accompanying vitamin D deficiency.
Aim of this study was to compare patients with PAOD grade II and grade IV with an age matched group of healthy controls in regards to their Vitamin D- and bone density status. Only patients without bone-active medication and normal renal and liver function were included in this study. Main results are given in the table below.
In summary, we found a high prevalence of vitamin D deficiency, secondary hyperparathyroidism and low bone mass in patients with advanced peripheral arterial occlusive disease. Some of the patients complaints are likely to be due to underlying osteomalacia or myopathy due to vitamin D deficiency. Further investigations are necessary to evaluate if vitamin D supplementation may mitigate some of the patients symptoms and help to improve bone mass in patients with more advanced stages of PAOD.
| controls | PAOD II | PAOD IV | p-value | |
| n=44 | n=45 | n=49 | POAD II vs IV | |
| Creatinin (mg/dl) | 0.95±0.01 | 0.97±0.12 | 0.93±0.14* | NS |
| Calcium (mmol/l) | 2.39±0.02 | 2.36±0.03 | 2.24±0.02** | p<0.001 |
| Magnesium (mmol/l) | NA | 0.97±0.1 | 0.9±0.12 | p<0.001 |
| Cross laps (nmol/l) | NA | 2.1±1.1 | 4.3±1.8 | p<0.0001 |
| Osteocalcin (ng/ml) | NA | 22.2±1.5 | 24.9±1.7 | NS |
| 25(OH)VitD3(ng/dl) | 19.1±1.4 | 19.3±1.1 | 9.6±0.7** | p<0.0001 |
| iPTH (pg/ml) | 38.5±2.4 | 45.3±3.5 | 66.3±3.6** | p<0.0001 |
| Z-score (femoral neck) | +0.37±0.16 | -0.12±0.14 | -1.11±0.18** | p<0.0001 |
| *p<0.05,**p<0.001 vs controls; NA = not applicable | ||||
AMYLIN INHIBITS OSTEOPENIA IN DIABETIC RATS
M. N. Horcajada-Molteni1, B. Chanteranne1, C. Picherit1, P. Lebecque1, M. J. Davicco1, V. Coxam1, A. A. Young2, J. P. Barlet1*
1U3M, INRA Clermont-Theix, 63122 France
2Amylin Pharmaceuticals Inc, San Diego, USA
Amylin, a peptide co-secreted with insulin, is absent in type 1 diabetes, a condition frequently associated with osteopenia. Amylin inhibits bone resorption and stimulates osteoblastic activity. We examined the effects of amylin replacement on bone loss in streptozotocin-induced diabetic rats.
Of fifty male Wistar rats, forty were made diabetic with intraperitoneal streptozotocin (STZ ; 50mg / kg).Ten non-diabetic control rats (CONT) received citrate buffer without STZ. Diabetic rats were divided into 4 groups, injected subcutaneously with rat amylin (AMY ; 45mg / kg), insulin (INS ; 12U / kg), both (same doses) or saline (STZ ; diabetic controls) once per day. After 40 days treatment, the animals were killed, blood sampled, and femurs removed. The left femur was tested for mechanical resistance (3 point-bending). The right femur was tested for total, diaphyseal (cortical) and metaphyseal (trabecular) bone densities using DEXA. None of the treatments had any effect upon femoral length and diameter. STZ had lower bone strength (145±SD 7 N) than CONT (164±SD 38). Total BMD (g / cm2) was significantly lower in STZ (0.2523±SD 0.0076) than in CONT (0.2826±SD 0.0055) as were metaphyseal and diaphyseal densities. Diabetic rats treated with amylin, insulin or both had bone strengths and bone densities that were undistinguishable from those in CONT. Changes in Ca content paralleled those for total BMD. Plasma osteocalcin concentration (ng/mL) was lower in STZ (7.6±SD 0.9) ; P<0.05) than in CONT (29.8±SD 1.7 ; P<0.05) or than in AMY (20.1±SD 0.7 ; P<0.05). Urinary deoxypyridinoline excretion (nmol / mmol creatinine) was similar in STZ and AMY (35.0±3.1 vs 35.1±SD 4.4), intermediate in INS (49.9±SD 2.7), and normalized in diabetic rats treated with both agents (58.8±SD 8.9 vs 63.2±SD 4.5 in CONT). Thus, in our STZ rat model of diabetic osteopenia, addition of amylin improved bone indices apparently by both inhibiting resorption and stimulating bone formation.
DIETARY PHOSPHORUS MODULATES TRABECULAR BONE MASS AND STRENGTH IN OVARIECTOMIZED RATS
R. Masuyama1*, M. Koshihara1, S. Tanaka2, T. Nakamura2, M. Uehara1, K. Suzuki1
1Tokyo University of Agriculture, Tokyo, Japan
2University of Occupational and Environmental Health
Dietary phosphorus plays a part in maintenance of the calcium homeostasis in the body including the alteration of hormone secretion, which regulates bone metabolism. Phosphorus is not indispensable nutrient same with calcium to form a bone mineral, however, if the intake balance against calcium collapses by excessive dietary phosphorus, it might cause insufficiency to the bone immediately. The effect of phosphorus on bone metabolism has not been resolved yet, to clarify whether the dietary phosphorus modulates bone mineralization, we demonstrated in this study using OVX rats with feeding diets composed with different levels of dietary phosphorus.
Fifteen Wistar strain female rats aged 12 weeks old were ovariectomized and fed a control diet (0.5% Ca, 0.5% P) for 4 weeks. Rats were divided into three groups and changed the diet to three kind of experimental diet: low-P (0.25% P), normal-P (0.5% P), high-P (1.0% P). Feces and urine were collected during 6 weeks of feeding period to investigate the balance of minerals. Serum and bone (femur, lumbar vertebra) mineral contents (BMC) and histology were analyzed at the end of the feeding period. Breaking forces (femur: bending, lumbar vertebra: compression) were also measured.
Apparent calcium absorption was decreased gradually according to the increase in dietary phosphorus levels, but no effect on the serum concentration of calcium was observed. BMC and ultimate load in lumbar vertebra were decreased significantly by the increase in dietary phosphorus levels, but were not observed in femur. In summary, the dietary phosphorus modulates trabecular bone mass through the intestinal absorption of calcium which might be suppressed by the formation of insoluble salt with phosphorus in the inside of lumen.
SECONDARY BONE ILLNESSES ASSOCIATED WITH CHRONIC PANCREATIC INSUFFICIENCY
A. Knauerhase1*, S. Krins1, M. Löhr2, R. Hampel1
1Klinik f. Innere Medizin, Rosotock, Germany
2Medizinische Klinik IV, Universitätsklinik, Mannheim, Germany
Secondary bone illnesses in patients with chronic pancreatic insufficiency are relatively rare.
From the spring of 1999 until the summer of 2000, we studied the effects of exocrine pancreatic insufficiency on the bone mineral density (BMD), on the presence of vertebral deformities and on the parameters of bone metabolism in 50 male patients (aged 33-69 years). The diagnosis of chronic pancreatitis was arrived at through sonography and by determining the level of pancreas elastase in the stool.
The bone mineral density was measured by means of DXA (Hologic QDR 1000, lumbar vertebra 1-4).
Vertebral deformities were demonstrated by means of x-rays of the thoracic and
lumbar spine.
Bone-specific alkaline phosphatase (AP), deoxypyridinoline, urine and serum calcium, serum phosphorus, parathyroid hormone and 25-OH-vitamin D were measured. In addition, the following were determined: total AP, aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma-GT, albumin, proteine, cholesterol, vitamin K, zinc, thyroid stimulating hormone (TSH) and testosterone.
Each patient was subjected to standardized interview.
Results (average±SD): The pancreas elastase level in the stool was, with a value of 181.1±193.2 microg/g, greatly reduced, as defined by the underlying illness. The serum calcium level was, at 2.3±0.13 mmol/l, reduced (normal range 2.3-2.6 mmol/ l);the calcium level in urine collected over 24 hours was reduced, at 2.7±2.6 mmol/ l (normal range 1.3-8.9 mmol/l); bone-specific AP was distinctly elevated, at 39.06±20.06 nmol/l (normal range 40-185 nmol/l), the urine deoxypyridinoline level was elevated, at 6.9±4.1 micromol/mmol creatinine (normal range 2.3-5.4 micromol/mmol creatinine); the DXA- T-score was -1.1±1.07, a value which is in the osteopenia range.
We conclude that exocrine pancreatic insufficiency associated with chronic pancreatitis leads to a dysfunction in vitamin and calcium metabolism, as well as an increased bone turnover rate. The effects on bone mineral density were only moderate. In the presence of further risk factors, these male patients may, however, very quickly become threatened by an increased bone fracture hazard. For these patients, it is to be recommended that at least a vitamin D substitution take place.
BONE MASS IN MALE PATIENTS SUFFERING FROM INFLAMATORY BOWEL DISEASE
R. Perez-Cano1*, M. A. Vazquez-Gamez1, M. J. Gomez-De-Tejada1, E. Lopez-Herrero1, M. J. Montoya-Garcia1, M. L. Castro2, R. Moruno-Garcia1, M. J. Miranda-Garcia1
1Department of Internal Medicine, Osteoporosis Unit, University Hospital Virgen Macarena
2Digestive Service, University Hospital Virgen Macarena
AIMS: To Know the prevalence of low bone mass in males with IBD and to determine all possible risk factors wich could be determinant of this decrease.
SUBJECTS AND METHODS: The lumbar spine and femoral neck bone mass was determined by DXA in 72 male patients with a mean age of 36.39 years (13-67) and suffering from IBD (35 with Crohn disease (CD) and 37 with Ulcerative Colitis (UC).
We also measured serum levels of PTH and 25(OH) vitamin D.
They were all asked about the following parameters: ingestion of milk products, alcohol and cigarettes; age at the time of the first outbreak, years of evolution and number of outbreaks of the disease; lactose intolerance; corticoids treatment; surgical therapy; other diseases and intake of drugs.
RESULTS: The bone mass was expressed in T-score and Z-score. The means obtained were: T-score (L2-L4) = -0.80; T-score (femur) = - 0.88; Z-score (L2-L4) =-0.58; Z-score (femur) = -0.53.
26.3% of the patients were osteopenic and 13.8% were osteoporotic. No significant differences were found regarding this fact between patients with CD and UC.
We observed a negative correlation between T-score and Z-score in spine and femoral neck and corticoids treatment when this treatment went on for more than 25 months. The patients with more than 15 years of evolution of the disease showed a lower bone mass in the lumbar spine than those who had fewer years of evolution.
It was also observed that the lower the serum levels of 25(OH) vitamin D the higher those of PTH and lower the bone mass in lumbar spine as well as in femoral neck.
Others studied parameters do not seem to have any influence in the decrease of bone mass in these patients.
CONCLUSIONS: There is a low bone mass in male patients with IBD. The lower serum levels of 25(OH) vitamin D and the longer evolution of the desease, the lower the bone mass. In addition, corticoids treatment contributes to this decrease.
DIETARY AND OTHER DETERMINANTS OF SUDDEN-ONSET POST-MENOPAUSAL BONE GAIN AND OSTEOARTHRITIS IN THE SPINE
R. Abraham1, J. Walton2, A. Nicholls1, J. Justice1, B. Wardley-Smith1, J. Reeve2 *
1Clinical Research Centre, Northwick Park Hospital, London, UK
2Department of Medicine, University of Cambridge, Cambridge, UK
Purpose: to identify dietary and other predictors of degenerative spine disease post-menopause. Methods: 64 women from a population sample, starting 1.7 years after menopause were scheduled over 15 years: 12 DPA/DXA measurements of L2-4 with careful QA using Hologic and European Spine Phantoms. At baseline each subject underwent diet assessment, with optimal accuracy and precision, by weighing of each food item on 2 weekdays and 1 weekend day. Then from food-tables, daily intakes of the following were calculated: carbohydrate, protein, fat, Ca++, Fe++(+), Zn++, Mg++, P, Cu++(+), vitamins A, C & D, thiamine, niacin, riboflavin, caffeine and fibre. Because of the multiplicity of dietary constituents, principal components were applied to the diet data and used to explore the dependence of bone loss on diet. All but 3 had measurements of lean body mass (40K method) from which accurate measurements of total body fat were derived by difference from body weight. Results: among 60 compliers, 2 had scoliosis and were excluded. 11 others developed classic appearances of osteoarthritis of the spine; or alternatively one or more of L2, L3 or L4 began mid-study a sudden increase in BMD leading to non parallelism in BMD trends (P<0.05). These subjects were grouped as candidate OA (cOA) cases. We used Cox proportional hazard modelling to explore the statistical determinants of cOA. % body fat was important in all models (P<0.01). Smoking status at baseline was found to be a positive risk determinant; but no principal component of diet significantly improved model fit to the model (adjusted for multiple testing: P=0.11). Body fat increased risk of cOA by 18 (6,33 95% CI)% per 1% increase and smoking increased risk 2.2-fold (1.1,4.2). Conclusions: prospective spinal bone densitometry is unlikely to be confounded by cOA in lean, (Body Mass Index 25 or under) non-smoking women, and some of the apparently protective effects of body weight on spine BMD may reflect increased degenerative disease. The adverse effect of smoking might sometimes be confounded by cOA.
BONE DENSITY AND FRACTURES IN PATIENTS WITH COELIAC DISEASE
M. W. J. Davie1*, I. Gaywood2, T. Masud3
1Charles Salt Research Centre, Oswestry, UK
2Lincoln County Hospital, Lincoln, UK
3Nottingham City Hospital, Nottingham, UK
Patients with Coeliac disease have low bone mineral density, but whether this is equally low at the spine or the upper femur and whether fracture rates are increased is uncertain. We studied 85 patients (M, 19, age 59.9±9.7yr; F, 66, 55.4±11.4yr) with coeliac disease. Fracture details and lifestyle data were collected by questionnaire; weight and height measured and bone mineral density measured by Hologic QDR4500W at L2-4 and the femoral neck. BMD was expressed as ‘z’ scores. All patients had been diagnosed by small bowel biopsy.
RESULTS: 28 women (42.4%) had 51 fractures and 7 men (36.8%) had 11 fractures. Women with fracture had low bone density at the femoral neck (FN) (mean -0.67, -.28:-1.06 95%CI) but this not significantly lower than women without fracture (-0.57, -.23:-0.91) although both were significantly lower than a z score of zero (p<0.05). At the lumbar spine BMD was not low (-0.28, 0.03:-0.59, p=ns); in women with fracture, BMD was low (-0.6, -0.22:-0.98, p<0.05) but it was not significantly different from the values in women without fracture. When BMD z score was related to age, values at LS in women under 50 yr were positive (0.25±0.8; mean±SD) and fell progressively with age to -0.99±0.79 in patients over 65yr (p for trend <0.05). Femoral neck BMD ‘z’ score was positively correlated with Body mass index (r=0.25, p<0.02) and with weight (r= 0.39, p<0.01). In men bone mineral density z score was -0.71±0.88 at the spine and -0.36±1.13 at the femoral neck (p=ns).
CONCLUSIONS: BMD is low in coeliac disease in women and correlates with body weight. Women under 50yr do not have low BMD at the lumbar spine; women over 50yr are at risk of losing bone in excess of that which might be expected. Whether this is caused by undertreatment or delay in diagnosis is uncertain.
DETERMINANTS OF OSTEOBLASTIC FUNCTION AMONG HOSPITALIZED ELDERLY: EVALUATION OF BASAL AND STIMULATED SERUM OSTEOCALCIN
V. Badot*, S. De Breucker, P. Bergmann, T. Pepersack, A. Peretz
CHU Brugmann, Free University of Brussems, Belgium
INTRODUCTION. Bone Gla Protein (BGP) is a specific osteoblast product, and serum BGP levels reflect osteoblast function. The relationship between osteoblast activity and aging is controversial. Discrepancies can be explained because the geriatric patient present particularities such as renal failure, immobilization, malnutrition, and high co-morbidity, which can alter serum osteocalcin concentration. AIMS: 1) to assess osteoblastic function in hospitalised geriatric patients as compared with a group of young people, 2) to define the influence of the social, functional, pathological and nutritional characteristics of the population on osteoblastic function. Methods: 43 patients older than 65 years, admitted in the geriatric unit and 20 healthy young subjects, were studied prospectively. After a baseline (day 0), the subjects and the patients received 1,25(OH) 2 D3 (Rocaltrol(r); Roche Laboratories) (2,0 µg / day) during the subsequent 6 days. Blood samples were obtained for determinations of serum levels of BGP BGP (N-Tac Osteocalcin, Incstar), calcium, alkaline phophatase, 1,25(OH)2D3 (Incstar), creatinine at day 0, 5, and 6. All patients were evaluated using comprehensive geriatric assessment. Multiple regression was used to investigate variables influencing BGP. RESULTS. Comprehensive geriatric assessment confirmed the geriatric characteristics of the studied patients. As compared with the controls, geriatric patients had a lower GFR, 25OHD and prealbumin; they had a higher serum level of urea and alkaline phosphatase. Basal BGP was 6.7 ng/ml in patients, not significantly different from controls, and it increased by 45% after 1,25(OH)2D3, which was significantly higher than in controls (p<0.02). Basal serum BGP was negatively correlated to Body Mass Index, (beta=0,26, p=0,003) and positively correlated to PTH (beta=0,29, p=0,04) and IGF1 (beta=0,26, p=0,035). The only determinant of BGP in controls was serum creatinine (beta=0,44, p=0,009). In patients, the increment of BGP after 1,25(OH)2D3 was significantly correlated with age (beta=0,29, p=0,04) and BMI (beta=0,42, p=0,02). CONCLUSION. Osteoblastic function assessed by basal or stimulated BGP concentrations measurements is maintained in the majority of geriatric patients. The major determinants of serum BGP in this aged population are BMI and PTH.
CHANGES IN BIOCHEMICAL MARKERS OF BONE METABOLISM IN MALE PATIENTS WITH HUMAN IMMUNODEFICIENCY VIRUS INFECTION DURING POTENT ANTIRETROVIRAL THERAPY
J. Teichmann1*, U. Lange1, G. Friese2, T. Discher2, J. Lohmeyer2, H. Stracke1, R. G. Bretzel1
1Medizinische Klinik und Poliklinik III, Klinikum der Justus-Liebig-Universität, Giessen, Germany
2Medizinische Klinik und Poliklinik II, Klinikum der Justus-Liebig-Universität, Giessen, Germany
Introduction: Alterations of bone metabolism have been observed in numerous studies of small groups of HIV-afflicted patients. A substantial number of patients with advanced HIV infection suffer from various metabolic and endocrine abnormalities.
Material and methods: In a study the effect of the protease inhibitor sanquinavir in combination with nucleosid analogue on biochemical markers of bone metabolism was investigated in 12 male late stage (CD4+lymphocyte count <50x106 cells/l) HIV-infected patients, in which we analyzed urine and serum samples for both calciotropic hormones and markers of bone metabolism and markers of the endocrine testicular function over a 8 week period. The patients were grouped according to the CDC criteria.
Results: In 10 out of 12 patients 8 week treatment with regimens including sanquinavir resulted in a both significant elevations of both serum osteocalcin as well as bone specific alkaline phosphatase (p<0.01). The alterations of bone resorption were also demonstrable, but these were less pronounced, with an increased urinary excretion of crosslinks (p<0.05). There were a significant correlation between the change of CD4+Lymphocyte count, log 10plasma HIV1 RNA copy number and both osteocalcin and bone specific alkaline phosphatase.
Discussion: The initiation of potent antiretroviral therapy in patients with advanced HIV infection can reduce the dissociation between bone formation and resorption. The potent combination antiretroviral therapy seems to be of additional relevance for the bone metabolism of male HIV-positive patients.
ANKYLOSING SPONDYLITIS: VITAMIN D STATUS AND RELATIONSHIP WITH DISEASE ACTIVITY
U. Lange1*, O. Jung2, J. Teichmann3
1Kerckhoff Clinic and Foundation, Department of Rheumatology, University Giessen, Germany
2IV. Medical Clinic - Nephrology, University Frankfurt/M. Germany
3Medical Clinic, University Giessen, Germany
Background: Ankylosing spondylitis (AS) is a chronic systemic inflammatory rheumatic disease with partial ossification. Nevertheless, vertebral compression fractures due to osteoporosis are a common but frequently unrecognized symptom in AS (1). If inflammatory activity in AS itself plays a major role in the pathophysiology of bone loss, osteopenia/osteoporosis in AS may be mediated by substances regulating both, the inflammatory process and bone turnover. A possible candidate for such a mediatory function is 1.25 vitamin D3 (2, 3).
Aim of the study/Methods: (1) to investigate the vitamin D status in AS (n=58), the relationship to disease activity (ESR, CRP, BASDAI), and markers of bone metabolism (PTH, 1.25 vitamin D3, 25 vitamin D3, calcium, bone alkaline phosphatase, crosslinks), and (2) to measure bone mineral density in different stages of disease by quantitative computer tomography (QCT). Control group: 45 healthy age-matched persons.
Results: Osteoporosis was seen in early as in progressive stages of AS (23/58 = 39.6%). Serum levels of 1.25 Vitamin D3 (P<0.001) and PTH (P<0.001) were negatively correlated to disease activity, the excretion of crosslinks showed a positive correlation with disease activity and 1.25 vitamin D3 and PTH were positively correlated to bone alkaline phosphatase.
Conclusion: Osteoporosis is frequent in AS. High disease activity is associated with an alteration in vitamin D metabolites and increased levels of bone resorption in active AS. The decreased levels of 1.25 vitamin D3 suggest further research to determine, if the low levels as an endogenous immunemodulator suppressing activated T cells and the cell proliferation may accelerate the inflammation process in AS. However, the results of the study suggest that an alteration in vitamin D metabolism may play a critical role and is a potential factor in the pathogenesis of osteopenia/osteporosis in AS. AS-patients should encompass evaluation of diagnostic procedures for osteopenia/osteoporosis in each stage of disease to identify those patients which will develop bone loss for an enable osteologic therapy (i.e. bisphosphonates).
References: (1) Will R et al. Osteoporosis in early ankylosing spondylitis: a primary pathological event? Lancet 1989, ii: 1483-5; (2) Baier R et al. Differential effects of 1.25 vitamin D3 on cell proliferation and calcitonin gene expression. Endocrinology 1994; 135: 2006-2011; (3) Bouillon R et al. Structure-function relationships in the vitamin D endocrine system. Endocr Rev 1995; 16: 200-257.
THE INTERACTION BETWEEN THE VITAMIN D RECEPTOR GENOTYPES AND LIFESTYLE FACTORS ON BONE MINERAL DENSITY
A. Morita1*, Y. Dohi2, Y. Ikeda1, M. Iki1, S. Kagamimori3, Y. Kagawa3, T. Matsuzaki3, H. Yoneshima3, F. Marumo4
1Kinki University School of Medicine, Osaka-Sayama, Japan
2Nara Medical University, Kashihara, Japan
3JPOS Study Group
4President, JPOS Study Group, Tokyo Medical and Dental University, Tokyo, Japan
Conflicting results have been reported on the association between the vitamin D receptor (VDR) genotype and bone mineral density (BMD). One of the reasons for these conflicts is that the prevalence of determinants of BMD other than the VDR genotype was different from a study to study. We investigated three polymorphisms found at ApaI, TaqI and FokI restriction sites with BMD and the interaction between these genotypes and lifestyle factors. We performed a large-scale epidemiologic study for osteoporosis called Japanese Population-based OSteoporosis (JPOS) Study. Fifty women were randomly selected from each of 5-year age stratified populations (15-79 years) in each of 7 municipalities throughout Japan. BMD at the lumbar spine, hip and distal forearm were determined using DXA. We measured, at the same time, body size and grip strength, and obtained the information of medical history and various lifestyle factors. DNA was extracted from peripheral lymphocytes in the subjects of the 3 of 7 study areas. The alleles were designated according to the absence (A, T, F) or presence (a, t, f) of the ApaI, TaqI and FokI restriction site, respectively. Among the 1,652 women who completed the study, 1,441 women served as the subjects for further analyses after exclusion of women who had medical and menstrual history affecting BMD.
The allele frequencies were 29.4% for A, 88.5% for T, and 62.5% for F. No significant departures from Hardy-Weinberg equilibrium were observed for all the polymorphisms. There was no significant difference in BMD over the ApaI, TaqI or FokI genotypes in both post- and pre-menopausal women. However, we found several significant interactions between the VDR genotype and lifestyle factors on BMD. Among the subjects with genotype tt or Tt, BMD at the femoral neck of those who had higher sporting activities in their high school age was greater than those with lower activities. Milk consumption showed a beneficial effect on BMD at the ultradistal forearm only in the postmenopausal women with genotype FF or Ff. It is important to implement preventive procedure suitable for individual genetic and lifestyle background.
EFFECT OF PUBERTY, AGEING AND GENDER ON SERUM N-TERMINAL PROPEPTIDE OF TYPE I PROCOLLAGEN (PINP) AND C-TERMINAL TELOPEPTIDE OF TYPE I COLLAGEN (S-CTX)
Y. M. Henry*, A. C. Eagleton, D. Fatayerji, R. Eastell
University of Sheffield, UK
Biochemical markers of bone turnover are affected by biological variability. Biological variables such as age and gender influence all markers of bone formation and resorption. This biological variability is important when establishing reference ranges. The aims of the present study were to examine the effects of puberty, ageing and gender on markers of bone turnover.
We studied 132 healthy Caucasian children (m:f 63:69, ages 11-19 years) and 279 healthy Caucasian adults (m:f 138:141, ages 20-80 years). We measured PINP as a marker of bone formation and S-CTX as a marker of bone resorption using the Elecsys(r) 2010 automated system. We considered children, young adults, mature adults and older adults to cover ages 11 to 19, 20 to 30, 30 to 45 and 45 to 80 years respectively. Bone turnover is low in the mature adult and so mean levels in all other groups were compared, as a ratio, to these subjects.
Compared to mature adults, PINP was 10 and 7 times higher in boys and girls respectively but only 1.5 and 1.3 times higher in young adult men and women respectively. In older men PINP was lower (0.84) than in mature men. Compared to mature adults, S-CTX was 1.7 and 1.2 times higher in young adult men and women respectively. In older women CTX was 1.5 times higher than mature adults, but in older men levels were lower (0.88).
We conclude that (a) higher bone formation in children compared to mature adults is due to the effects of pubertal growth; (b) the higher bone formation and resorption in boys and young adult men compared to their female counterparts is due their later skeletal maturity; (c) higher bone resorption in older women compared to mature adults is due to the effects of the menopause. This pattern of bone modelling and remodelling emphasises the need for age- and gender-specific reference ranges.
CHANGES IN BIOCHEMICAL MARKERS OF BONE TURNOVER AFTER RENAL TRANSPLANTATION USING EITHER TACROLIMUS OR CYCLOSPORIN BASED IMMUMNOSUPPRESSION
K. A. Harding1*, M. D. Stone1, W. D. Fraser2, G. Morris-Stiff3, W. A. Jurewicz3
1Bone Research Unit, Academic Department of Geriatric Medicine, University of Wales College of Medicine, Cardiff, UK
2Department of Clinical Chemistry, University of Liverpoool, UK
3Transplantation Research Group, University of Wales College of Medicine, Cardiff, UK
In a randomised controlled trial comparing tacrolimus (Prograf) and cyclosporin (Neoral) after renal transplantation we have measured biochemical markers of bone turnover.
Patients were randomised to receive either cyclosporin (8mg/kg/day) or tacrolimus (0.2mg/kg/day) as part of triple therapy which included azathioprine (1.5mg/kg/day) and prednisolone (20mg/day tapered to 5mg/day by the end of the third post transplant month).
Blood and urine samples were taken at baseline, 3 months and 6 months.
We have results of parathyroid hormone, bone specific alkaline phosphatase, P1CP and plasma DPD on 32 patients.
PTH levels are grossly elevated at the time of transplant and fall dramatically between 0-3 months as expected. PTH levels in the cyclosporin group then rise significantly between 3-6 months (p<0.05) but stay the same in the tacrolimus group. This may be because cyclosporin can affect the function of the transplanted kidney.
Bone specific alkaline phosphatase and P1CP are both markers of bone formation. P1CP is excreted via the liver and should therefore not be affected by the renal status of the patient. Bone specific alkaline phosphatase rises significantly, within the normal range, in both groups between 0-3 months and 0-6 months.
P1CP rises significantly (p<0.05) between 0-3 months in the tacrolimus group but is unchanged in the cyclosporin group.
Plasma DPD is a marker of bone resorption and is grossly elevated above the reference range at baseline. It falls dramatically between 0-3 months in both groups and then plateaus. There is a significant difference between the 2 drug groups at 3 months suggesting bone resorption may be greater in the cyclosporin group during this time.
HIGH CYSTATIN C IS AN INDICATOR OF DECLINING RENAL FUNCTION AND IS RELATED TO OSTEOPOROSIS IN A LONGITUDINAL POPULATION STUDY
E. Waern1*, J. Kanis2, A. Lindahl3, G. Lindstedt3, S. Ljunghall4, D. Mellström1
1Dept of Geriatric Medicine, Göteborg University, Sweden
2Dept of Human Metabolism, Sheffield University, UK
3Dept of Clinical Chemistry and Transfusion Medicine, Göteborg University, Sweden
4AstraZeneca
Renal function declines with age which may affect the metabolism of calcium and vitamin D, resulting in secondary hyperparathyroidism. The question is if mild to moderate renal failure can be related to osteoporosis in the elderly?
600 76-year old men and women were studied in a community based population study. 152 were followed longitudinally and were reexamined at the age of 86. Bloodsamples were drawn after an overnight fast for determining serum cystatin C, creatinine, osteocalcin, calcitriol, Hb and PTH. The bone mineral density (BMD) was measured with DPA in calcaneus in 76 years of age and with DXA Hologic 4500 in hip, spine and total body in 86 years of age. GFR was measured with Iohexol-clearance in 50 86 year olds.
Serum Cystatin C increased from 1.53 mg/L at the age of 76 to 1.63 mg/L at the age of 86 (p=0.007)as a sign of declining renal function. Osteocalcin and PTH increased and calcitriol decreased between 76 and 86 years of age. At the age of 76 Cystatin C was positively correlated to serum creatinine, osteocalcin and PTH. Cystatin C was was negatively correlated to calcitriol and Hb. In 86 years of age BMD in femur neck was negatively correlated to Cystatin C.
Renal function declines with age and this increase the risk for secondary hyperparathyroidism in the elderly. This lead to an increased bone turnover and osteoporosis.
EFFECTS OF LOW DOSE METHOTREXATE ON BONE MINERAL DENSITY AND BONE TURNOVER
L. Ogunremi1*, R. Wills1, J. Barron2, S. Patel3
1Osteoporosis Unit, St George's Hospital, London, UK
2Dept Clinical Chemistry, St Helier Hospital, Carshalton, Surrey, UK
3Dept Rheumatology, St Helier Hospital, Carshalton, Surrey, UK
Low dose methotrexate (MTX) is an established treatment for inflammatory rheumatic diseases and psoriasis. In vitro studies show that methotrexate may have an adverse effect on bone metabolism and MTX osteopathy has been described. In patients with rheumatoid arthritis, MTX does not seem to cause bone loss, although this may be because MTX treatment reduces inflammatory activity of RA which itself is known to cause osteopenia. It is unclear whether MTX treatment, in the absence of inflammatory disease, will adversely effect the skeleton. The aim of this study was to assess bone density (BMD) and turnover in patients with psoriasis (without arthritis) who were treated with low dose methotrexate.
We assessed 30 consenting patients with psoriasis treated with methotrexate and obtained detailed history from questionnaire and case notes. All patients underwent bone densitometry and had markers of bone turnover measured. 21 patients agreed to have bone densitometry repeated a mean of 21 months (range 17 to 24) later.
There were 18 F and 12 M, mean age 56 yrs (range 32 to 85). Mean duration of MTX use was 4 yrs (0.3 to 21), mean cumulative dose was 2.5g and mean weekly dose was 15 mg (2.5 to 40). Mean lumbar spine Z score was 0.87 (95% CI 0.19 to 0.15) and mean femoral neck Z score was 0.24 (95% CI – 0.21 to 0.69). Markers of bone turnover (bone specific alkaline phosphatase and urinary crosslinks) were within the normal ranges. BMD or bone turnover markers were not related to weekly or cumulative methotrexate dose or duration of treatment. Lumbar spine and femoral neck BMD did not change significantly. Thus mean change in lumbar spine BMD was 3.5% (95% CI –1.9 to 2.0) and femoral neck BMD –0.8% (95% CI –2.7 to 1.1) over the 21 months of follow-up.
These data suggest that low dose MTX treatment, in the doses used in this study, does not have clinically significant adverse effects on bone density or bone turnover.
BONE MINERAL DENSITY INCREASED WITH URINARY CALCIUM IN POSTMENOPAUSAL CALCIUM OXALATE STONE FORMERS ON ESTROGEN THERAPY
K. M. Kellum1,4*, J. S. Lindberg1, L. L. Hamm2, F. E. Husserl1, A. L. Burshell1, D. J. Kok3, J. B. Copley1, E. Reisen4, F. E. C. Cole1
1Ochsner Hospital, New Orleans, USA
2Tulane University, New Orleans, USA
3Erasmus Medical Centre, Rotterdam, Netherlands
4Louisiana State University, New Orleans, USA
Bone mineral density (BMD) of the lumbar spine was lower in calcium oxalate stone formers (CaOxSF) with hypercalciuria. Estrogen replacement therapy (ERT) is used to preserve bone in postmenopausal women. We studied relationships between calcium excretion, (ERT) and femoral neck BMD (fnBMD) in postmenopausal (PmCaOxSF).
FnBMD was determined by DEXA in fifty-four PmCaOxSF. Calcium excretion was determined in twenty four-hour urine collections from twenty-two of these patients on ERT and thirty two who were not on ERT.
For the 22 estrogen treated patients, calcium excretion rate (milligram/24hours) was positively, linearly correlated with fnBMD (p<0.005 for each). In contrast, for the patients not on estrogen, there was no correlation (p=0.2584) between these variables.
These observations support a hypothesis that in spite of increased calcium excretion, estrogen therapy has a positive effect on fnBMD in PMSF.
THE INFLUENCE OF PREGNANCY AND LACTATION ON OS CALCIS ULTRASONOMETRY IN POSTMENOPAUSAL WOMEN
P. Hadji*, M. Kalder, K. Bock, M. Meyer-Wittkopft, S. Schmidt, K. D. Schulz
Philipps-University of Marburg, Marburg, Germany
Previous studies have suggested that reproductive factors such as parity and lactation may be associated with low bone mass and osteoporotic fractures. This study aimed to elucidate the relation between parity, lactation and bone mass ascertained by quantitative ultrasonometry (QUS) in postmenopausal women.
Altogether 2080 postmenopausal women (mean age 58.8±8.2 SD years) in whom diseases and drug treatments known to affect bone metabolism had been excluded underwent ultrasonometry at the heel. Speed of sound (SOS), broadband ultrasound attenuation (BUA) and Stiffness index (SI) of the Os Calcis were measured using the Achilles ultrasonometer (GE/Lunar). The ultrasonometry variables (SOS, BUA and SI) were compared in nulliparous versus parous women and in nursing versus non-nursing women. Because group differences in confounding factors can be important, a second comparison of variables was undertaken using a randomized sample of equal size, matched for possible confounding variables such as age and BMI (matched pairs).
Our results demonstrated no significant association of parity, including the number of life births and bone status in postmenopausal women. We also did not observe any association of lactation, including it’s duration and bone status.
Our results indicate that reproductive factors such as parity and lactation are not associated with status of Os Calcis ultrasonometry in postmenopausal women. Longitudinal studies are needed to improve our understanding of the mechanism of bone turnover during pregnancy and lactation.
BREAST CANCER AND OSTEOPOROSIS - A LINK BETWEEN TWO FREQUENT DISEASES OF POSTMENOPAUSAL WOMEN
P. Hadji*, M. Kalder, K. Bock, U. S. Albert, G. Emons, K. D. Schulz
Philipps-University of Marburg, Marburg, Germany
Estrogens play important roles in the pathophysiology of breast and bone. A number of recent studies have suggested an inverse relation between both diseases. The aim of the present study was to evaluate the relation between bone mass and breast cancer and to investigate if cumulative exposure to estrogens could explain this association.
Speed of sound (SOS), broadband ultrasound attenuation (BUA), and stiffness index (SI) of the Os calcaneus were measured in 2492 women, mean age 54.4 years, using the "Achilles" ultrasonometer (Lunar Corp., Madison, WI). 242 patients had a history of breast cancer, while 2250 women had not. Due to the significant group differences, we randomly formed an equally sized sample of healthy women who were matched for confounding variables such as age, BMI, cumulative exposure to estrogens and others. We calculated the odds ratios to examine the relation of ultrasonometry results to the risk of breast cancer.
Women with breast cancer were older, showed a higher weight, BMI, number of parity and lactation, age at menopause and a longer exposure to estrogens. SOS and SI were significantly higher in women with breast cancer even after matching for confounding variables (p<0.001). Odds ratios for the risk of breast cancer were 1.0, 1.6, 3.4 and 2.9 from the lowest to the highest quartile of SI (p for trend <0.001).
Women with breast cancer have higher bone mass than controls, even after matching for confounding variables. Women in the higher quartiles of bone mass are at higher risk for breast cancer than those in the lower quartiles. Although the biologic mechanisms linking bone mass to the risk of breast cancer are not fully understood, factors other than cumulative exposure to estrogens must play a role.
BONE AND METABOLIC EFFECTS OF A NEW MUTATION OF THE CYP19 GENE IN A MALE PATIENT
L. E. Maffei1*, G. Tubert1, Y. Murata2, E. Simpson2, C. Clyne2, C. Aranda3, H. H. Salerni4, S. Davis5
1Consultorios Asociados de Endocrinología, Buenos Aires, Argentina
2Prince Henry's Institute of Medical Research, Clayton, Australia
3TCBA, Diagnóstico, Buenos Aires, Argentina
4CIEM, Buenos Aires, Argentina
5Jean Hailes Fdn, Clayton, Australia
Recent findings concerning the role of estrogens in the male have resulted in new insights into the critical effects of estrogen on bone metabolism.
The influence of estrogen on lipoprotein-lipid and carbohydrate metabolism and the cardiovascular system are currently being studied, plus its role in male fertility.
The biosynthesis of estrogens is catalyzed by aromatase, the enzyme encoded by the CYP19 gene. We report a mutation in the CYP19 gene in a 28 year old adopted caucasian male who presented with progressive linear skeletal growth, failure of epiphyseal closure and severe bone pain. He had central obesity (waist/hip ratio:1.04) long limbs, height 182 cm, genu valgum, bilateral cryptorchidism. The karyotype was XY. The biological bone age was of a 15 year old male and the vertebral and the femoral neck mineral density were low (Tscores -3.31 and -2.29). Bone metabolisme studies showed high osteocalcin 24 ng/ml (3,4-12) and deoxypyridoline 9.9 nmol/mmol creatinine (2,3- 5,4).
Treatment with testosterone did not improve bone density or bone age but was associated with elevated hepatic enzymes (TGO and TGP) and the appearence of acanthosis nigricans, confirmed by biopsy, on the neck and the axillae. The liver biopsy revealed severe steatosis.
LH and testosterone were lower normal range; FSH was elevated 18 mu/ml (2,2-6) and the estradiol was below 10 pg/ml (30-90). The testicular biopsy showed total germ cell depletion (Sertoli cell only features). Sequencing of the gene revealed a novel homozygous point mutation in exon V; GAA-AAA, resulting in a predicted Glu210Lys conversion, but the results of the in vitro assays showed that this aminoacid substitution has no effect on the aromatase activity. However the mutation would be predicted to destroy the splice junction consensus sequence, leading to read-through to a cryptic stop codon within the intron.
Low dose transdermal estradiol therapy has now been institued to induce epiphyseal closure, inhibit bone resorption and alleviated bone pain. The effects on hepatic steatosis, acantosis nigricans and bone mineralisation will be monitored.
A CASE CONTROL STUDY OF SEX STEROIDS AND BONE TURNOVER IN MEN WITH SYMPTOMATIC VERTEBRAL FRACTURES
S. P. Tuck1*, A. C. Scane1, R. M. Francis1, M. Diver2, W. D. Fraser2, D. Fatayerji2, R. Eastell3
1Bone Clinic, Freeman Hospital, Newcastle upon Tyne, UK
2Royal Liverpool Hospital, Liverpool, UK
3Northern general Hospital, Sheffield, UK
We have previously performed a case control study comparing 91 men with a past history of symptomatic vertebral fractures (VF) with 91 age-matched controls subjects. The men with VF had lower bone mineral density (BMD) at the lumbar spine and at all sites in the proximal femur (p<0.001). We have now measured the biochemical markers of bone turnover and sex steroid concentrations in a sub-group of 57 case control pairs (median age 63 years, range 27-80). Men with VF had a higher mean±SEM urine deoxypyridinoline/creatinine ratio (VF 5.51±0.6 nmol/mmol, controls 4.03±0.28; p<0.05) and bone specific alkaline phophatase (VF 15.8+-0.7 microg/l, controls 11.8±0.5: p<0.001), suggesting an increase in bone turnover. Sex hormone binding globulin (SHBG) was also higher (VF 46.6±3.0 nmol/l, controls 36.1±2.1; p<0.01) and this was associated with a lower free androgen index (VF0.47±0.04 nmol/nmol, controls 0.57±0.04: p<0.05) and free oestradiol index (VF 1.78±0.18 pmol/nmol, controls 2.44±0.29; p<0.05). There was no difference in total testosterone, bioavailable testosterone or total oestradiol betweeen the two groups. In the men with VF, femoral neck BMD was correlated with SHBG (r=-0.44, p<0.001), free androgen index (r=0.36, p<0.01), bioavailable testosterone (r=0.27, p<0.05) and free oestradiol index (r=0.38, p<0.01). Urine deoxypyridinoline/creatinine was correlated with SHBG (r=0.29, p<0.05), free androgen index (r=-0.38, p<0.01), bioavailable testosterone (r=-0.35, p<0.01) and total oestradiol (r=-0.27, p<0.05), whereas bone specific alkaline phophatase was correlated with SHBG alone (r=0.34, p<0.01). Our results show that men with symptomatic vertebral fractures have biochemical evidence of lower free sex steroid concentrations and increased bone turnover, which may have contributed to the development of osteoporosis.
INFLUENCE OF ESTROGEN RECEPTOR GENOTYPE ON BONE MINERAL DENSITY IN CHINESE HAN WOMEN
Y. Xue*, D. Li
Department of Biochemistry, Beijing Ji Shui Tan Hospital, Beijing, P.R. China
The objective of this study was to investigate the relationship between bone mineral density (BMD) and polymorpism of the estrogen receptor gene (ERG) in Chinese Han women.
Methods: The genotypes of the PvuII (Pp) and XbaI(Xx) restriction fragment length polymorphism (RFLP) of the ER gene were detected using PCR amplification followed by restriction enzyme digestion in 177 healthy Chinese Han women aged 33-83 years (60.4±9.6 years) and BMD at the lumbar spine, hip and forearm was measured using dual energy x-ray absorptiometry.
Results: The frequency of the different ER genotypes and the BMD values of lumbar spine (L2-4), femoral neck (FN) and forearm (AM) in 117 Chinese Han women were shown in table.
Conclusions: (1) The high frequency distribution of ER genotype in Chinese Han women is Pp (41.2%) and Xx (48%). (2) pp genotype is associated with a low BMD of forearm and XX genotype is associated with a low BMD of femoral neck in Chinese Han women. ER genotype may be useful in the prevention and management of osteoporosis.
| Genotype | PP | Pp | pp |
| n | 38 | 73 | 66 |
| Distribution | 0.215 | 0.412 | 0.373 |
| L2-4BMD(g/cm2) | 0.895±0.202 | 0.866±0.186 | 0.842±0.192 |
| FN BMD(g/cm2) | 0.732±0.132 | 0.692±0.134 | 0.674±0.137 |
| AM BMD(g/cm2) | 0.445±0.108 | 0.397±0.102 | 0.339*±0.1 |
| Genotype | XX | Xx | xx |
| n | 45 | 85 | 47 |
| Distribution | 0.254 | 0.48 | 0.266 |
| L2-4BMD(g/cm2) | 0.885±0.214 | 0.86±0.148 | 0.86±0.218 |
| FN BMD(g/cm2) | 0.656±0.054 | 0.716±0.125 | 0.727**±0.124 |
| AM BMD(g/cm2) | 0.398±0.83 | 0.406±0.11 | 0.375±0.115 |
| *p<0.05 vs. PP; **p<0.05 vs. XX | |||
PROXIMAL POSTMENOPAUSAL BONE MINERAL DENSITY (BMD) VARIATION ACCORDING TO TYPE OF PREMATURE MENOPAUSE
D. Hadjidakis*, P. Katsavochristos, A. Mylonakis, M. Sfakianakis, S. A. Raptis
2nd Department of Internal Medicine-Propaedeutic, Research Institute and Diabetes Center, Athens University, Evangelismos and Evgenidion Hospitals, Athens, Greece
Decreased BMD is a known sequel of premature menopause, the latter constituting a risk factor for osteoporosis. However early natural and early surgical menopause differ in their mode of occurrence. In order to investigate possible differences of bone mineral behavior in a life period known to represent skeletal consequences of estrogen deprivation such as the immediate and proximal postmenopausal, we studied 264 women, 99 with early natural menopause (EMP), body mass index (BMI) 26.8±3.8 kg/m², age at menopause (AAM) 39.5±4.1 yrs, (mean ± 1 SD) and 165 with early surgical menopause (SUMP) BMI 27.2±4.1 kg/ m², AAM 39.7±3.7 yrs stratified in 5 three-year segments between 45-59 yrs of age. BMD was measured at L2-L4 and proximal femur by the DEXA method. None of the women suffered from any disease or had received any medication affecting bone metabolism. Comparisons were performed between SUMP and EMP in the same age segment and between age segments within each menopausal category. No significant differences of BMI and AAM existed either among age segments or between SUMP and EMP in each segment. Regarding BMD values and age-adjusted BMD (Z scores) no significant differences were observed among age segments in either menopausal category at any anatomic area (except between extreme segments). SUMP women presented higher BMD values compared to EMP only in the 2 younger age segments at all areas (p< 0.01 to 0.05). In the same age segments SUMP category exhibited greater percentages of women with normal BMD compared to EMP (p< 0.05). The latter presented greater proportion of osteoporotic women in all age segments (p< 0.05 to 0.001). Conclusions: Early natural menopause appears to exert a negative influence on bone density of any anatomic area, compared to the early surgical one in the proximal to menopause ages. The proportion of osteopenic and osteoporotic women seems to be lower after surgical than after natural early menopause. These differences may be accounted for by the different hormonal physiology of the 2 types of premature menopause.
EFFECT OF EARLY MENOPAUSE ON BONE MINERAL DENSITY AND BIOCHEMICAL MARKERS
C. S. Shin1*, J. H. Kim1, Y. J. Park1, S. Y. Kim1, J. G. Kim2
1Dept of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea
2Dept of Obstetric and Gynecology, Seoul National University College of Medicine, Seoul, Korea
Menopause represents a critical life step characterized by complex endocrine changes, which affect musculoskeletal system. After the disappearance of the menstrual cycle, estrogen deficiency is the most important factor in bone loss. Early menopause, whether it be natural or surgical, is one of the established risk factors for osteoporosis. However, it is still unclear whether bone loss rate in women with early menopause is different from that in women whose menopause has occurred later. This study was undertaken to establish whether healthy women with early or late menopause have different bone mass, biochemical bone markers and rates of bone loss. Methods: Ninty-one postmenopausal healthy women (mean age 55±4) were divided into 3 groups according to their age at menopause (AAM): early menopause (EMP) group with AAM < 43 years (n=32), intermediate menopause (IMP) group with AAM between 43 and 50 years (n=33), and late menopause (LMP) with AAM > 50 years. We compared clinical and laboratory profiles between EMP and LMP groups only. Bone mineral density (BMD) was measured using a dual energy X-ray absorptiometry (DEXA) at the lumbar spine, femur neck, femur trochanter, and Wards triangle. Serum levels of bone-specific alkaline phosphatase and osteocalcin, and urinary levels of calcium excretion, deoxypyridinoline and N-telopeptide were measured using a commercial kit. Results: Body mass index (BMI) in EMP group was significantly lower than that in LMP group (22.8±3.1 vs. 24.7±3.5, p<0.01). However, year since menopause (YSM) adjusted BMD at all sites and all the biochemical markers in the EMP group were not different from those in LMP group. When we selected 15 subjects from each group matched by age and BMI, BMD at femur neck in EMP group was lower than in LMP group (p<0.05). However, the difference disappeared after adjusting for YSM. All the biochemical markers were not different in the two groups matched by age and BMI. When we analyzed data from all subjects (n=91), lumbar spine and Wards triangle BMD was significantly correlated with chronological age, YSM and trochanteric BMD was correlated with BMI. However, AAM was not correlated with BMD or biochemical markers. Conclusion: Women with early menopause did not exhibit lower BMD or increased biochemical markers compared to women with late menopause.
CERIVASTATIN INCREASES SOME CANCELLOUS BONE FORMATION INDICES IN OVX RATS
S. C. Miller1*, B. M. Bowman1, C. Bagi2
1University of Utah, Salt Lake City, USA
2Bayer Pharmaceutical Division, West Haven, CT, USA
Statins, HMG coenzyme-A reductase inhibitors, effectively decrease low-density lipoprotein (LDL) cholesterol but also have been found to have possible beneficial effects in the skeleton. Cerivastatin is effective at doses lower than other available statins reducing systemic exposure and thus decreasing potential toxicity. The aim of this study was to examine Cerivastatin effects in vivo on cancellous bone.
An ovariectomized (OVX) rat model was used to study the effects of Cerivastatin. Sprague-Dawley rats were OVX at 100-120 days of age. Experimental groups included: 1) OVX+Estradiol, 2) Mevinolin, postive control, 3) Low-dose, 0.01mg/kg/d, 4) Mid-dose, 0.1mg/kg/d, 5) OVX control and 6) Sham OVX. Drug doses and vehicles were given orally for 6 wks and the Estradiol by slow-release pellets. The treatments began the day after OVX and fluorochrome bone markers given at 4 wks (calcein, 10mg/kg) and 5 wks (tertracycline, 25mg/kg) post-OVX. The proximal tibia metaphysis was used for the cancellous bone histomorphometry.
The OVX response compared to the Sham group exhibited the expected increased turnover following ovariectomy. The OVX+E group had suppressed bone formation, significantly lower than all other groups including the Sham group as expected. The Mid-dose and Low-dose groups had a significant increase in percent double-labeled surface, percent mineralizing surface and bone formation rate (surface referent) compared to all other groups.
The trabecular structure of the metaphyseal area also showed significant differences in the Low-dose group. The Pm/Area ratio (trabecular size), the percent of free-to-free struts and the trabecular separation (marrow space, by star volume) were significantly lower in the Low-dose compared to the OVX controls.
In this OVX model, Cerivastatin increased some indices of bone formation over those of OVX controls, providing additional evidence for a beneficial effect of this statin on the skeleton.
EFFECTS OF ENALAPRIL AND AT I RECEPTOR ANTAGONIST LOSARTAN ON THE SKELETON OF FEMALE RATS.
P. D. Broulik1*, V. Tesaø2, T. Zíma3, M. Jirsa2
13rd Int. Clinic of First Medical Faculty, Prague, Czech Republic
2lst Int. Clinic of First Medical Faculty, Prague, Czech Republic
3Inst. of Clinical Chemistry of Medical Faculty, Prague, Czech Republic
No data are available whether AT 1 receptor antagonist losartan affect the skeleton and there is little information on the activity of ACE inhibitor enalapril on bone metabolism. We studied l4 week old female Wistar rats treated daily with losartan 2 mg/kg/b.w., enalapril 0.4 mg/kg/b.w. or saline. The volume and density of the femora were measured and also morphometric measurements were performed. From bone ash calcium and phosphorus were determined. Administration of the enalapril and losartan in a dose recommended for the treatment of hypertension to intact female rats was not found to cause a significant changes in the bone density and mineral content of the femur and morphometric measurements compared to that in the intact animals.
COMPARISON OF MICROSTRUCTURAL CHANGES AMONG THREE OSTEOPOROTIC RAT MODELS INDUCED BY STEROID, OVARIECTOMY AND SCIATIC NEURECTOMY
M. Ito*, A. Nishida, M. Uetani, K. Hayashi
Department of Radiology, Nagasaki University, Japan
Purpose: The changes of trabecular microstructure were compared among three different osteoporosis rat models: steroid-induced (ST), ovariectomy (OVX), and sciatic neurectomy (NX).
Materials and Methods: Three different osteoporosis rat models, 8-week-old female Lewis rats; ST-induced (n=10)(10mg/kg i.m., 2/week for 4 weeks), OVX (n=9), NX (n=10) models. Each osteoporosis model has its control; non-ST (n=10), and sham operation (n=10, n=10)). At 12-week of age, L5 and left tibia were harvested. These bone samples were scanned using micro-CT (Scanco Medical) to calculate metric (BV/TV, Tb.N, Tb.Sp, and Tb.Th) and non-metric parameters (structure model index (SMI) and trabecular bone pattern factor (TBPf)). After micro-CT scan, mechanical test was performed in L5.
Results
1. All parameters were significantly different in OVX group (p<0.0001), and BV/TV (p<0.05), SMI (p<0.05), Tb.Th (p<0.05) and TBPf (p<0.05) were significantly different in NX group in comparison with their individual controls, while no parameter was significantly different in ST group.
2. The differences were greater in the tibia than in the spine, especially in the NX group.
3. In the tibia, Tb.Th, Tb.Sp, Tb.N, and TBPf (p<0.05) in ST group, and all parameters in OVX and NX groups were significantly different in comparison with their controls. The difference of most parameters was greater in NX group than in OVX group.
4. In OVX group, the heterogeneity of the microstructure was seen to be greater in comparison with ST and NX groups in the tibia.
5. ST group showed that the changes of Tb.Sp and Tb.N were disproportional to bone mass (BV/TV) in the spine and tibia.
6. While the max load of ST and NX groups were not significantly different, some microstructural parameters were significantly different from their individual controls.
6. The correlations of the max load were significant with S/V and BV/TV in ST and NX groups, and with all parameters in OVX group.
Conclusion
The appearance of bone loss are different among 3 different osteoporosis models. The changes of microstructure are greater in the tibia than in the spine after intervention. The change of bone strength is considered to be preceded by the change of microstructure.
THREE-DIMENSIONAL MORPHOMETRIC ANALYSIS OF THREE DIFFERENT SKELETAL SITES IN OVARIECTOMIZED RAT MODEL OF OSTEOPOROSIS: EFFECT OF PREVENTATIVE ADMINISTRATION OF ALFACALCIDOL AND ALENDRONATE
A. Nishida1*, M. Ito1, K. Hayashi1, A. Shiraishi2, S. Higashi2, Y. Uchida2
1Department of Radiology, Nagasaki University, Japan
2Product Research Laboratory, Chugai Pharmaceutical Co, Ltd
Purpose: To compare the changes of trabecular microstructure of lumbar spine (L5), distal metaphysis of femur and proximal metaphysis of tibia induced by preventative administration of therapeutic agents in ovariectomized rat model of osteoporosis.
Method/Materials: (Alfacalcidol study) 10-month-old Winster-Imanichi rats were ovariectomized (OVX) or sham-operated. Alfacalcidol (0.2 microg/kg) was given orally to one OVX group (n=7) 5 times a week for 6 months. Vehicle was given to both the sham group (n=7) and the other OVX group (n=7) under the same protocol. After the treatment, L5, femur and tibia were harvested.
(Alendronate study) 3-month-old Sprague-Dawley rats were OVX or sham-operated. Alendronate (20 microg/kg) was given subcutaneously to one OVX group (n=10) 2 times a week for 3 months. Vehicle injections were given to both sham group (n=11) and other OVX group (n=10) under the same protocol. After the treatment, L5 and tibia were harvested.
These samples were scanned using a micro-CT20 (Scanco Medical). 250 slices from each L5 were obtained with 13 micron-slice thickness. 150 slices of each metaphysis of femur and proximal metaphysis of tibia were obtained with 13 micron-slice thickness. Metric and non-metric parameters were directly assessed.
Results/ Conclusion: Similar results were obtained in Alfacalcidol study and Alendronate study. There were significant changes in BV/TV, Tb.Th, Tb.N, Tb.Sp, SMI and TBPf in OVX group compared with sham group. Administration of theraputic agents prevented the changes of these structural parameters, especially non-metric parameters. Responses to OVX and treatment were greater in strongly weight-bearing sites such as tibia and femur than in slightly weight-bearing sites such as lumbar spine.
OXIDATIVE PARAMETERS CORRELATE WITH BONE MINERAL DENSITY IN COPPER DEFICIENT RATS
V. Coxam*, I. Bureau, M. J. Davicco, B. Chanteranne, E. Gueux, J. P. Barlet, Y. Rayssiguier
U3M, INRA Clermont-Theix, 63122 France
This study was undertaken to better define the relationship between Cu deficiency and bone health in an animal model of osteoporosis, the ovariectomized rat. The experiment was carried out on 20 male and 36 female Wistar rats split into 2 groups according to their Cu dietary consumption (microg Cu/g) (0.6 in deficient animals (Cu-) vs 6 in controls (Cu+)). At 3 weeks of age, half of the females were castrated (OVX), the others being sham-operated (SH) and then fed the appropriate diet for 7 weeks.
Total femoral bone mineral density (BMD, g/cm2) was higher in males (0.1857±SD 0.003) than in females (0.1764±SD 0.003). However, both genders displayed osteopenia, when Cu intake decreased (0.1578±SD 0.003 and 0.1652±SD 0.004). Such a deficiency exacerbates bone loss in OVX rats (0.1414±SD 0.003 vs 0.1693±SD 0.003 in OVX Cu+). Metaphyseal and diaphyseal BMD followed the same pattern, as did bone mineral content at each site. This process could be mainly explained by a decreased bone formation: OC values (ng/ ml) (56.3±SD 2.0 (Cu-) vs 75.6±SD 5.5 in Cu+ males) and (53.0±SD 2.9 (Cu-) vs 70.0±SD 4.0 in Cu+ SH females). DPD (DPD/creatinine, nmoles/mmoles), a marker for resorption, was not significantly modified by the respective diets (340.2±SD 24.1 Cu-) vs 357.7±SD 18.6 in Cu+ males and 300.5±SD 25.2 (Cu-) vs 296.8±SD 26.2 in Cu+ SH females).
In this experiment, the copper status of SH and OVX females was similar. Thus, catalytic involvement of copper as a cofactor for collagen synthesis cannot explain the more drastic bone loss in OVX. On the opposite, when fed the Cu deficient diets, OVX rats exhibited significantly higher TBARS values in tissues than SH (186±SD 37 vs 66±10 nmoles/g for pancreas). As the dramatic decrease of SOD activities induced by Cu deficiency is considered as a model of oxidation stress, the antioxidant properties of endogenous estrogens, could explain the sexual difference in the expression of Cu deficiency.
Consequently, Cu depletion can exacerbate bone mineral loss in postmenopausal osteoporosis, probably through the induced oxidative stress conditions.
STRUCTURAL ANALYSIS OF OVARIECTOMIZED MONKEY MANDIBLE USING MICRO CT
S. Ejiri1*, M. Tanaka2, E. Toyaoka2, H. Tsusaki3, K. Fukuzaki3, H. Miyajima3, S. Kohno2, H. Ozawa1
1Niigata University, Dept of Anatomy, Faculty of Dentistry, Niigata, Japan
2Niigata University, Dept of Prosthodontics, Faculty of Dentistry, Niigata, Japan
3Shin Nippon Biomedical Laboratories Ltd., Dept of the 2nd Safety Research, Kagoshima, Japan
Recently, epidemiological studies suggested the positive relationship existed between the systemic osteoporosis and oral bone loss and/or teeth loss in postmenopausal women. However, the histomorphometrical and maicro-structural changes in mandibles following estrogen deficiency were scarcely reported. In order to clarify the effect of estrogen deficiency on the mandibles of postmenopausal women, we assessed ovariectomized monkey mandibles using micro CT.
Fourteen monkeys were divided into two groups. The OVX group was ovariectomized bilaterally and the Sham group was subjected to sham surgery. Seventy-eight weeks after surgery, the animals were sacrificed and the mandibles were excised. The coronal planes of the bones through the distal root of the first molar were assessed by micro CT. The histomorphometrical measurement and node-strut analysis of the trabecular area were performed with an image analysis system. We also measered the thickness and volume of the cortical bone, and the number and volume of vascular spaces in the cortical bone.
The volume, thickness and number of trabecular bones in the OVX group significantly decreased as compared with those of the Sham group. The value of the trabecular separation in the OVX group was higher than that of Sham group. The node-strut analysis showed a statistically significant decrease in the values of TSL/ TV and CtNd/TSL in the OVX group. Severe trabecular bone loss occurred in the basal part of the mandibular body of the OVX group. In the values of the volume and width of the cortical bones, there was no significant difference between two groups. However, the number and volume of vascular spaces in the cortical bone of the OVX group significantly increased in comparison with that of the Sham group.
From these results, It is clearly demonstrated that estrogen deficiency caused trabecular bone loss and osteoporotic changes in the cortical bone of the monkey mandible. The results also suggest that bone loss and structural fragility of trabecular bones supporting teeth accelerate tooth loss in postmenopausal women.
ESTABLISHMENT OF AN OSTEOPOROTIC GOAT ANIMAL MODEL
W. S. Siu1*, N. M. Cheung1, P. P. Y. Lui1, D. H. K. Chow2, A. James3, L. Qin1, K. S. Leung1
1Department of Orthopaedics and Traumatology, Prince of Wales Hospital, The Chinese University of Hong Kong
2The Rehabilitation Engineering Center, The Hong Kong Polytechnics University
3Laboratory Animal Services Center, The Chinese University of Hong Kong
The establishment of large animal osteoporotic animal models are essential for studying fracture fixation enhancement mimicking human biology. The present study aimed at establishment of osteoporotic animal model in goats.
Sixteen Chinese mountain goats were used for ovariectomy with low calcium diet (Ovx, n=11) or sham operation (Sham, n=5). Monthly photodensitometric analysis on proximal tibial metaphysis and calcaneum was performed. Two iliac crest biopsies at baseline and 6 months after ovariectomy were taken for bone mineral density (BMD) measurement using peripheral Quantitative Computed Tomography (pQCT). After euthanasia of the goat, lumbar spine (L2 and L7), humeral heads and calcaneus were collected for BMD measurement. The humeral heads and calcaneus of the goat were then prepared for indentation test.
pQCT BMD measurement showed that on average there was a significant 32% (p=0.028) decrease in trabecular BMD in the iliac crest biopsy six months after ovariectomy. BMD at L2 and L7, calcaneum and humeral head autopsies were also reduced by 26 - 32% (p ranged from 0.017 to 0.033) when compared with sham-operated controls. Photodensitometry showed that standardized bone density of goat started to decrease after ovariectomy. Significant decreases of 21.6% in proximal tibial metaphysis and 18.1% in calcaneum were found in the Ovx group six months after the operation (p=0.028 and p=0.043, respectively). Indentation test on the humeral heads and calcaneus revealed a substantial 56 - 60% decrease (p=0.017 for both) in energy required for a indentation displacement of 3 mm in the Ovx group compared with the Sham group. Such a decrease was significantly correlated to the decrease of BMD of the relative specimen (r2 = 0.521 and 0.742 for humeral head and calcaneum, respectively, p<0.001 for both). In conclusion, the results of this experimental study demonstrated ovariectomy plus low calcium diet could induce bone loss and deterioration of mechanical properties of bone in goats.
EFFECT OF DIET COMPOSITION ON BONE RESORPTION IN RATS: NO ROLE FOR METABOLICALLY PRODUCED ACID
R. C. Mühlbauer*, A. Lozano, A. Reinli
Bone Biology Dept. Clinical Res. University of Bern, Bern, Switzerland
It is held that vegetarian nutrition positively influences bone metabolism by its base excess which is thought to buffer the metabolic acid load considered to be deleterious to bone. Animal proteins are claimed to be deleterious to bone due to their amino acid composition metabolically generating acid.
We have now investigated the impact on bone resorption of metabolically produced acid by feeding to rats either a "vegetarian" diet containing potato protein and soy flour as main protein sources or a diet based on animal protein ("casein" diet). Onion, previously shown to inhibit bone resorption, was used as a tool. Urinary titrable acid (amount of base to reach pH 7.4) and ammonium were used to monitor proton excretion, tritiated tetracycline from prelabeled rats to monitor bone resorption.
Rats fed a "vegetarian" diet excreted daily -0.024±0.031 (SEM) mmoles protons, reflecting the basic nature of vegetable nutrition. Upon switching rats to the "casein" diet the proton excretion increased to 16.3±0.4 mmoles (10 day cumulative), reflecting the metabolic acid production of the "casein" diet and the powerful acid excretory capacity of the kidneys. When the purified casein was replaced with purified vegetable proteins (soyamin 90, potato protein and a mixture thereof) no effect on bone resorption was found, indicating that the source of the protein plays no role on bone resorption. Addition of 7% onion to the "casein" diet decreased the proton excretion by 17±3% (p<0.01) and bone resorption by 18±2% (p<0.001) confirming previous results.
To mimic the base excess of onion we treated rats receiving the "casein" diet with potassium citrate. Despite a 54±4% (p<0.001), 84±6% (p<0.001) and 119±5% (p<0.001) decrease in titrable acid excretion induced by feeding daily 126, 252 and 504 mg of potassium citrate respectively, bone resorption was not different from controls receiving the "casein" diet only.
Thus, metabolically produced acid plays no role on bone resorption in our conditions. Furthermore, although the base excess of onion correlates with the inhibitory effect on bone resorption the two phenomena cannot be causally related.
THE EFFECT OF OVARIECTOMY ON BONE LOSS IN THE EDENTULOUS AND DENTATE MANDIBLE
E. S. Elsubeihi1*, M. D. Grynpas2, A. M. Cheung3, G. A. Zarb1, J. N. M. Heersche1
1Faculty of Dentistry, University of Toronto, Toronto, ON, Canada.
2Mount Sinai Hospital, Toronto, ON, Canada.
3The Toronto General Hospital, Toronto, ON, Canada.
It is unclear whether postmenopausal bone loss in the dentate and/or edentulous mandible parallels bone loss in the axial and appendicular skeleton. This is because it is difficult to design controlled human studies to investigate these changes using reliable, sensitive and noninvasive techniques. We investigated the effect of ovariectomy (OVX) on bone changes in the edentulous and dentate mandible using adult female rats. First we established the time required for healing of the extraction sockets after extraction of the mandibular teeth. To do this we extracted molars and incisor on one side of the mandible in 6 months old female rats and sacrificed 10 rats in each group at 14 days, 1, 2, and 4 months after extraction. Using bone mineral density (BMD), radiographic and histomorphometric measurements, we established that healing was completed 4 months after extraction. In the next experiment, mandibular teeth were extracted and animals were ovariectomized 4 months after extraction. Twelve animals of each group were sacrificed at 6 weeks, 6- and 9-months post-OVX. Edentulous and dentate mandibles as well as femora, tibiae and lumbar vertebrae were dissected and BMD was measured using Dual Energy X-ray Absorptiometry. Forteen samples of each bone were scanned 3 times to calculate coefficient of variation (CV). The decrease in BMD values (%) in different bones of OVX group and the control group is shown in the table. Our results show that OVX has no significant effect on BMD of the dentate mandible, while bone loss in the edentulous mandible is similar to that occurring in the femur, tibia and lumbar vertebrae. The results indicate that, while normal function did not prevent bone loss in the femur and tibia, masticatory force prevented bone loss in the dentate mandible. Histomorphometric evaluation is currently in progress, and will be presented at the meeting.
| Bone | 6 weeks | 6 months | 9 months | CV |
| post-OVX | post-OVX | post-OVX | ||
| Femur | -4.2% | -11.3% | -10.5% | 1.3% |
| Proximal femur | -4.5% | -7.8% | -9.4% | 1.7% |
| Tibia | -1.9% | -10.1% | -10.2% | 1.2% |
| Proximal tibia | -6.0% | -15.8% | -12.8% | 1.5% |
| Lumbar vertebrae | -4.7% | -13.5% | -10.4% | 2.2% |
| Dentate mandible | -1.32% | -2.5% | -1.08% | 1.0% |
| Edentulous mandible | -5.3% | -11.4% | -11.1% | 1.3% |
| Table: Values represent % decrease in BMD and coefficient of variation. | ||||
BOTH HIGH DIET CALCIUM AND MECHANICAL STIMULATION ARE REQUIRED TO PROTECT AGAINST OVARIECTOMY-INDUCED BONE LOSS IN THE RAT
H. A. Morris*, A. J. Moore, P. D. O'Loughlin, B. Jansen, R. Larik
Institute of Medical and Veterinary Science, Adelaide, South Australia, 5000
Dietary calcium supplementation inhibits bone resorption and protects against vertebral fractures in postmenopausal women. Whether this effect is uniform throughout the skeleton is uncertain. We report data on the interaction between dietary calcium levels and estrogen status on bone architecture in the adult rat at various skeletal regions experiencing high and low mechanical strain energies. Groups of 6 ovary-intact (O-I) and 6 ovariectomised (Ovx) rats (5 months of age) were fed one of 4 semi-synthetic diets containing between 0.05% to 1% calcium (Ca) for 7 weeks. Distal femora and L1-L3 vertebrae (Vert) were prepared for quantitative histomorphometry using established resin embedding techniques. Quantitative static and dynamic bone histomorphometry were performed on 5 µm sections with trabecular bone volume (BV/TV), trabecular thickness (Tb.Th), and trabecular number (Tb.N) calculated using a Quantimet image analysis system. Osteoclast and osteoblast variables demonstrated an inverse relationship with dietary calcium in both O-I and Ovx animals at all sites (P<0.05). At the distal femoral epiphysis (Epi), BV/TV was not different between Ovx and O-I groups in the 1% Ca rats in contrast to the distal femoral metaphysis (Meta) and Vert [Mean BV/TV (%);Epi O-I 36.7, Ovx 35.4 (NS); Meta O-I 26.9, Ovx 12 (P<0.01); Vert O-I 34.8, Ovx 25.9 (P<0.01)]. With 0.4% and lower Ca diets, BV/TV was significantly reduced at all sites in Ovx compared with O-I rats (P<0.01). The reduction of BV/TV in Ovx rats occurred as a result of a reduction in both Tb.Th (P<0.02) and Tb.N (P<0.001). Dietary calcium is a major determinant of bone cell activity independent of oestrogen status and skeletal site in the rat model. High dietary calcium was able to protect against Ovx-induced bone loss only in a region experiencing high mechanical strain energy, the distal femoral epiphysis. In other regions, including the lumbar vertebrae, significant bone loss was observed. These data suggest that both mechanical strain and high dietary calcium are required to protect bone mineral when bone resorption is increased, such as induced by ovariectomy.
EFFECTS OF NADROPARIN ON THE OSSEOUS SYSTEM IN RATS
J. Folwarczna*, W. Janiec, M. Pytlik, I. Kaczmarczyk-Sedlak, M. Barej, B. Nowiñska, U. Cegiela, L. Sliwiñski
Department of Pharmacology, Silesian School of Medicine, Sosnowiec, Poland
Nadroparin calcium is a low-molecular-weight heparin. Low-molecular-weight heparins have a number of advantages over standard heparin (heparin); it is not clear if low-molecular-weight heparins have less effect on bones than heparin. Administration of heparin can lead to osteoporosis. The aim of the present study was to investigate the effects of nadroparin on the rat osseous system and compare them with those of heparin.
The experiments were carried out on female Wistar rats (13-15 weeks old at the beginning of the experiment), divided into 5 groups: I Control, II Nadroparin (1000 anti-Xa IU/kg s.c. daily), III Nadroparin (2000 anti-Xa IU/kg s.c. daily), IV Heparin (1000 IU/kg s.c. daily), V Heparin (2000 IU/kg s.c. daily). Nadroparin or heparin were administered for 4 weeks. Bone length and mass, mass of mineral substances and calcium content in the tibia, femur and L4 vertebra, endosteal and periosteal transverse growth, width of endosteal and periosteal osteoid, transverse cross-section area of the diaphysis and of the marrow cavity in the tibia, width of epiphyseal cartilage, width of trabeculae in the epiphysis and metaphysis in the femur were examined. Mechanical properties of the femur: maximal deformation of the diaphysis, force causing fracture of the diaphysis and force causing fracture of the femoral neck were also studied.
Nadroparin caused unfavourable changes in the osseous system of female rats, similar to those caused by heparin. Nadroparin and heparin caused osteopenia in rats (disorder of bone formation and intensification of bone resorption). Decreases in the bone mineral mass/bone mass ratio and bone calcium content were observed. In the tibia, the transverse cross-section area of the marrow cavity and the width of endosteal osteoid increased, the endosteal transverse growth decreased. The width of trabeculae in the femur decreased. Worsening of the mechanical properties of the femur was observed. The changes caused by nadroparin in some parameters were slightly weaker than those caused by heparin.
SKELETAL EFFECTS OF BENZO[A]PYRENE AND RESVERATROL IN ESTROGEN-REPLETED OVARIECTOMIZED RATS
L. Lee1,2, J. Lee1,2, R. F. Casper1,3, J. F. Savouret4, M. D. Grynpas1,2*
1Samuel Lunenfeld Research Institute, Mount Sinai Hospital
2Department of Laboratory Medicine and Pathobiology, University of Toronto
3Division of Reproductive Sciences, Mount Sinai Hospital
4INSERM Unit 135, Hosp de Bicetre (Le Kremlin-Bicetre)
Cigarette smoking has been linked to increase bone fractures and decrease bone mineral density. BaP and DMBA are two aryl hydrocarbon receptor (AhR) ligands found in the tar fraction of cigarettes. Resveratrol, a component in red wine, is an antagonist to the AhR and moderate alcohol consumption has been shown to be beneficial to bone. We hypothesised that the BaP/DMBA is responsible for bone loss and that resveratrol can prevent this loss. Nine month-old Sprague-Dawley rats were ovariectomized and given a continuous basal dose of estrogen. The loss of ovarian function allowed us to study whether there was a direct effect of BaP/ DMBA on bone. The animals were injected weekly, subcutaneously for 15 weeks. Seventy-two rats were divided in to six groups as shown in the table below. DEXA, trabecular histomorphometry and strut analysis were used to determine the cumulative effect of the treatments on bone. The DEXA results in the lumbar spine and femur showed a significant (p<0.05) decrease in bone mineral density in the BaP/DMBA-treated animals vs. intact rats. The structural parameters of histomorphometry were not significantly altered with the treatment of BaP/DMBA. However, the osteoid parameters were significantly increased with BaP/DMBA addition, mimicking the ovariectomized group (p<0.05). The combination of BaP/ DMBA and resveratrol did not increase the osteoid parameters when compared to the BaP/DMBA-treated group. A similar trend was observed in the dynamic histomorphometry; bone formation was increased in the BaP/DMBA-treated animals, similar to the ovariectomized rats. Resveratrol was able to partially prevent this increase in bone formation. Bone connectivity was not changed when examined with struts analysis. From this study, we concluded that BaP/DMBA induced bone loss and increased bone turnover. This induced-bone loss may be partially prevented with resveratrol.
| Group | Ovariectomy | Estrogen | BaP/DMBA | Resveratrol |
| 250microg/kg | 1250microg/kg | |||
| Intact | - | - | - | - |
| OVX | + | - | - | - |
| OVX+E2 | + | + | - | - |
| OVX+E2+BaP/DMBA | + | + | + | - |
| OVX+E2+BaP/DMBA+Res | + | + | + | + |
| OVX+E2+Res | + | + | - | + |
