BMC Values Research Articles

Hand grip strength, vitamin D status, and diets as predictors of bone health in 6–12 years old school children

BackgroundVitamin D and calcium-rich foods, exposure to sunlight, and physical activities (PA) play a pivotal role in promoting the production of sufficient vitamin D and improving grip strength needed for better bone health among school children.PurposeThis study aimed to determine the effects of hand grip muscle strength (HGS), vitamin D in addition to diets, and PA on bone health status among 6–12 years old schoolchildren.MethodsThis study was based on a cross-sectional observational design, which was descriptive in nature. A diverse sample of 560 elementary school children aged 6–12 years old were invited to participate in this descriptive cross-sectional study. The Dual-Energy X-Ray Absorptiometry (DXA), QUS technique, and ACTi graph GT1M accelerometer were used respectively as a valid tools to identify BMD, BMC, and other parameters of bone health like c-BUA values and bone stiffness (SI), and physical activity (PA) of all individuals participated in this study. In addition, a hydraulic dynamometer was used to measure hand grip strength among the participants. Moreover, an immunoassay technique was used to measure the serum levels of vitamin 25(OH)D level, and bone metabolism markers; NTX, DPD, Ca, and sBAP in all participants. Bone loss (osteoporosis) was cross-sectionally predicted in 19.64% of the total population, most of whom were girls (14.3% vs. 5.4% for boys; P = 0.01). Compared to boys, the incidence of osteoporosis was higher and significantly correlated in girls with lower HGS, deficient vitamin D, inadequate vitamin D and Ca intake, greater adiposity, poor PA, and lower sun exposure. Also, in girls, lower vitamin 25(OH)D levels, and poor HGS were shown to be significantly associated with lower values of BMD, BMC, SI, and higher values of bone resorption markers; NTX, DPD, and sBAP and lower serum Ca than do in boys. The findings suggested that deficient vitamin D, lower HGS, adiposity, PA, and sun exposure as related risk factors to the pravelence of bone loss among school children, particularly in girls. In addition, these parameters might be considered diagnostic non-invasive predictors of bone health for clinical use in epidemiological contexts; however, more studies are required.

Evaluating the Effect of Jointly Administering Synthetic Graft and Ankaferd Blood Stopper for Bone Recovery in Created Bone Deformities in Diabetic Rats

Objective: In the present paper, it was purposed to examine the late impacts of bone tissue recoveries in combination with synthetic grafts and Ankaferd Blood Stopper (ABS), which are effective in bone wound healing in diabetic rats.
 Methods: A total of 64 Wistar albino male rats with diabetes were studied. A bone deformity was generated in the calvarium of diabetic rats. These diabetic rats are divided into 4 different groups. Only saline was applied to the bone defect in group 1, Beta-tricalcium phosphate (β-TCP) graft was administered to Group 2, ABS solution to Group 3, (β-TCP+ABS) were administered to group 4. Eight rats from each group were sacrificed on the 28th day and another 8 rats on the 56th day. Immunohistochemical, histopathological, and Dual Energy X-ray Absorptiometry (DEXA) analyzes of the obtained samples were made.
 Results: In histopathological measurements, osteoblastic activity and bone regeneration were considerably higher in the group treated with group 2 and group 4 when compared to the control group on the 28th and 56th day (p˂ .05). Western blotting findings showed that the osteopontin (OP) and osteonectin (ON) expression at 28th day increased dramatically in the treated with group 4. DEXA analyzes revealed that BMC values in groups treated with group 2, group 3 and group 4 on 28th day were considerably higher than the control group (p˂ .05).
 Conclusion: We can believe and conclude that ABS in combination with a β-TCP bone graft will produce more successful outcomes on wound
 healing and formation of new bone in diabetic rats.

Characteristics of total body and appendicular bone mineral content and density in Japanese collegiate Sumo wrestlers

The purpose of this study was to explore the characteristics of total body and appendicular bone mineral content (BMC, kg) and bone mineral density (BMD, g/cm2) in Japanese collegiate Sumo wrestlers. A total of 54 male college Sumo wrestlers were recruited for the study and assigned to two groups according to their body weight (middleweight, 85–115 kg, n = 23 and heavyweight, > 115 kg, n = 31). The BMC, BMD, fat mass, and lean soft tissue mass (LSTM) values were measured using dual-energy X-ray absorptiometry for the total body and appendicular regions. Heavyweight Sumo wrestlers had significantly higher body weight, fat mass, and LSTM compared to middleweight Sumo wrestlers. The mean total body and regional BMC values were significantly higher in heavyweight than in middleweight Sumo wrestlers. The total body and leg BMD was significantly higher in heavyweight than in middleweight Sumo wrestlers, and was significantly correlated with body weight, but not arm BMD. The present study indicates that BMC and BMD might not sharply elevate among even heavyweight athletes, although heavier Sumo wrestlers had a greater BMC and BMD.

Relationship between physical activity, lean body mass, and bone mass in the Mexican adult population.

To evaluate the effect of different kinds of leisure-time physical activity (LTPA) on bone mass values and its association with lean mass (LM) in the whole body (wb) and limbs of a large sample of Mexican men and premenopausal (pre-MP) women. We conducted a cross-sectional analysis of data from the Health Workers Cohort Study. Bone mineral content (BMC, kg), bone area (cm2), and LM (kg) were measured with DXA. The LTPA level and the "sedentary" condition were determined using a validated questionnaire adapted for the Mexican population. One-way ANOVA tests evaluated the differences in weight, height, body mass index, and wb, lower limb (ll) and upper limb (ul) BMC and LM between the active (those who engaged in LTPA) and sedentary group. Relationships between BMC and LM values were analyzed. Slopes of the curves and Z scores of LTPA groups with respect to the sedentary group were compared. In men, both wb-BMC and ll-BMC were significantly higher in the groups performing basketball, football, tennis, weightlifting, and running, and all wb-LM, ll-LM, and ul-LM were higher in running, weightlifting, football, and basketball groups with respect to the sedentary group. Both the Z scores and the slopes of BMC-vs-LM relationships were higher than the controls, but only in the ll of male basketball and football players. Our findings demonstrate that some types of LTPA with relatively high/medium impact on bones, such as football, basketball, tennis, and weightlifting, improve both BMC and LM compared to sedentary individuals. Finally, this relationship is stronger for the bones found in the legs and it seems that women are less sensitive to this effect, possibly due to hormonal, dietary, and pharmacological reasons.

Peripheral quantitative computed tomography (pQCT) in 12- and 24-month-old children - Practical aspects and descriptive data.

Peripheral quantitative computed tomography (pQCT) is a useful tool to assess detailed bone characteristics. Its utility in infants is however limited due to lack of reference data and technical challenges. The purpose of this study was to provide data on length- and weight-adjusted pQCT values and to present a quality grading system for healthy children aged 12 and 24months. As a part of the Vitamin D intervention in Infants (VIDI) trial, we collected pQCT and anthropometric data from 855 children at 12months and from 784 children at 24months. Bone mineral content (BMC; mg/mm), volumetric bone mineral density (vBMD; mg/cm3), cross-sectional area (CSA; mm2), polar-moment of inertia (PMI; mm4), and periosteal circumference (PsC; mm) were assessed for total bone at 20% distal site of the left tibia using pQCT (Stratec XCT2000L). We evaluated the impact of scan quality on bone measures. Total bone parameters were assessed for boys and girls separately. The means of the bone parameters were also compared in relation to age. The associations between bone parameters and weight, length, sex and scan quality were analyzed. We included scans with sufficient quality (Grade 1-5) in the final analyses: 679/855 (79%) at 12months and 709/784 (90%) at 24months. Altogether 39% of the scans at 12months and 51% at 24months were of good or excellent quality (Grade 1-2). Scan quality had an impact on BMCs at 12 and 24months (p=0.001 and p=0.017, respectively) but not on other bone parameters. Boys presented greater total bone BMC, CSA, PMI and PsC values at 12 and 24months but vBMDs were similar. All bone parameters showed a significant increase between 12 and 24months for both sexes. When adjusting bone parameters for weight, length and scan quality, differences between sexes disappeared. Weight was the strongest modifier of BMC, CSA, PMI and PsS at 12 and 24months. This study increases our understanding on bone parameters in young children and demonstrates the suitability of pQCT in bone research in infants. The described pQCT data and scan quality grading system should prove useful in evaluating data reliability in research settings. NCT1723852.

Analytical bone calcium and bone ash from mature laying hens correlates to bone mineral content calculated from quantitative computed tomography scans.

Laying hen skeletal health continues to be an industry priority. Bone ash and bone Ca quantification in laying hen long bones provides valuable information on skeletal health. Unfortunately, these measurements can only be accomplished by sacrificing hens, thus making longitudinal measurements on the same hen impossible. Quantitative computed tomography (QCT), used with a calcium hydroxyapatite phantom, has been used to determine bone density of wings and legs as well as live hens throughout the production cycle by scanning with a calcium hydroxyapatite phantom. QCT has also been used to scan live hens throughout the production cycle. The purpose of this study was to determine how QCT calculated bone mineral content (QCT BMC) corresponds to analytical bone Ca and bone ash. Wing and leg quarters from 72-wk-old W-36 hens were QCT scanned along with a QCT Phantom. After scanning, humeri, femurs, and tibias were cleaned, divided into epiphysis (E) and diaphysis (D), fat extracted, ashed, and digested under nitric acid, and Ca was determined by atomic absorption spectroscopy was used to determine E, D, and whole bone Ca. Four bones/type were used for E and D, while 6 bones/type were used for whole bone measurements. A second set of bones were prepared to determine correlation of BMC to bone ash. QCT scans were analyzed with Mimics software (Materialise NV, Leuven, Belgium) to calculate bone volume and density in Hounsfield units. Utilizing the QCT phantom and bone volume, BMC was calculated for E, D, and whole bone. Data were analyzed with regression analysis and Pearson correlation coefficients were determined. Analytical Ca was correlated to QCT BMC for E (R = 0.84, P < 0.01), D (R = 0.99, P < 0.01), and whole bone (R = 0.97, P < 0.01). Whole bone ash was highly correlated to QCT BMC for femur (N = 47, R = 0.97, P < 0.001), tibia (N = 50, R = 0.94, P < 0.001), and keel (N 50, R = 0.94, P < 0.001). Whole bone ash and QCT BMC values of femur and tibia were not different (P = 0.39 and 0.22 respectively). Based on this information, QCT could provide relative quantitative assessment of total bone mineral in live birds proving useful in long-term studies.

Bone mineral density and bone mineral content among female elite athletes.

Exercise is a protective factor for the appearance of osteoporosis, but not all physical activities have the same effect on bones. Low-impact sports, like swimming, may a have a negative or no effect. The aim of the present study is to evaluate bone mineral density (BMD, g/cm2) and bone mineral content (BMC, kg) among female high performance athletes from aquatic and non-aquatic sports and to assess possible differences with sedentary controls. Participants are elite female athletes over 18 years, from the Spanish Olympic teams, with at least 12-15 h of weekly training on aquatic sports: swimming (n = 19), synchronized swimming (n = 24) and water polo (n = 14), and elite female athletes from non-aquatic sports: professional football players of Futbol Club Barcelona team (n = 92), Spanish national volleyball (n = 26) and field hockey teams (n = 29) as well as sedentary controls (n = 126). Bone mineral density scans was performed using dual-energy X-ray absorptiometry for whole body, segmental analysis, proximal femur and lumbar spine. Non-aquatic female athletes have total and segments BMC and BMD values higher than those of aquatic athletes, that in turn show similar BMD values compared to controls. BMD in lumbar spine and proximal femur was higher in non-aquatic sports compared to aquatic sports athletes and both were higher than controls. BMD is not negatively compromised by the practice of aquatic sports at a highly competitive level. However, non-aquatic female athletes show a higher BMD. Time training out of the water improves BMD. Our findings suggest that swimming and synchronized swimming should be combined with weight-bearing, impact or strength activities, as they do not seem to be osteogenic sports.

Investigation of the effect of combined use of alloplastic-based tricalcium phosphate bone graft and antihemorrhagic plant extract (ABS) on bone regeneration in surgically induced bone defects in nondiabetic rats: an experimental animal study

In this experimental study, we aimed to evaluate the late period effects of the combination of Ankaferd Blood Stopper (ABS), which has bone wound healing effects, and β-tricalcium phosphate (TCP) on the regeneration of bone tissue through histopathological, immunohistochemical, and radiological (dual energy X-ray absorptiometry - DEXA) methods in nondiabetic rats. Sixty-four Wistar albino male rats were used. In the calvaria of the rats, a bone defect 7.0 mm in diameter was created. These rats were divided into 4 different groups. Group 1 was the control group without any treatment, a 0.125 mL Β-TCP graft was applied to Group 2, a 0.125 mL ABS was applied to Group 3, and a 0.125 mL (β-TCP + ABS) mixture was applied to group 4. Half of the rats were sacrificed on day 28 and the other half on day 56. Histopathological, immunohistochemical, and DEXA analyses of the specimens were performed after the experiment. As a result of the histopathological analysis, osteoblastic activity and new bone formation were found to be significantly higher in Group 2, Group 3, and Group 4 than the control group on day 28 (P < 0.05). However, inflammatory cell infiltration and vascular dilatation and hemorrhage decreased significantly compared to the control group (P < 0.05). The histopathological analysis in rats on day 56 showed that osteoblastic activity in Group 2 and Group 4 was significantly higher than in the control group, but there was a statistically significant decrease in inflammatory cell infiltration and vascular dilatation and hemorrhage compared to the control group (P < 0.05). New bone formation in Group 2, Group 3, and Group 4 was significantly higher than in the control group. Western blotting findings revealed that the osteonectin and osteopontin expression on day 28 was increased significantly in Group 2 and Group 4. DEXA analyses revealed that BMC values in Group 2 and Group 4 on day 28 were significantly higher than in the control group (P < 0.05). There was no significant difference in bone mineral density values on the 28th and 56th days (P > 0.05). The use of both β-TCP + ABS and only ABS had positive effects on wound healing and bone formation in nondiabetic rats.

Track and Field Practice and Bone Outcomes among Adolescents: A Pilot Study (ABCD-Growth Study).

BackgroundOsteoporosis is considered a public health problem with high worldwide prevalence. One approach to prevention is through the promotion of physical activity, especially exercise, during adolescence.MethodsThis study compared bone variables in different body segments in adolescents according to participation in track and field. The study included 34 adolescents (22 boys), of whom 17 were track and field athletes and 17 were control subjects. Bone mineral density (BMD, g/cm2) and bone mineral content (BMC, g) were analyzed using dual energy X-ray absorptiometry (total body stratified by body segments). Peak height velocity was used to estimate somatic maturation.ResultsAthletes had higher BMD (P=0.003) and BMC (P=0.011) values in the lower limbs and higher whole body BMD (P=0.025) than the control group. However, when adjusted for confounding factors, the difference was not maintained. The groups had similar lean soft tissue values (P=0.094). Training overload was positively correlated with BMD in the upper limbs (r=0.504; 95% confidence interval, 0.031-0.793). Although track and field athletes had higher BMD and BMC values in the lower limbs, these differences were not significant when adjusted for confounding factors.ConclusionsTrack and field participation in adolescence appears to influence BMD and BMC in lower limbs, and fat-free mass seems to mediate this effect. Also, higher training loads were found to be positive for bone health in upper limbs.

Bone and Spinal Muscular Atrophy

Spinal Muscular Atrophy (SMA) is an autosomal recessive neuromuscular disease, leading to progressive denervation atrophy in the involved skeletal muscles. Bone status has been poorly studied. We assessed bone metabolism, bone mineral density (BMD) and fractures in 30 children (age range 15–171months) affected by SMA types 2 and 3.Eighteen children (60%) had higher than normal levels of CTx (bone resorption marker); 25-OH vitamin D was in the lower range of normal (below 20ng/ml in 9 children and below 12ng/ml in 2). Lumbar spine BMAD (bone mineral apparent density) Z-score was below −1.5 in 50% of children. According to clinical records, four children had sustained four peripheral fractures; on spine X-rays, we observed 9 previously undiagnosed vertebral fractures in 7 children. There was a significant inverse regression between PTH and 25-OH D levels, and a significant regression between BMC and BMAD values and the scores of motor-functional tests.Even if this study could not establish the pathogenesis of bone derangements in SMA, its main findings – reduced bone density, low 25OH vitamin D levels, increased bone resorption markers and asymptomatic vertebral fractures also in very young patients – strongly suggest that even young subjects affected by SMA should be considered at risk of osteopenia and even osteoporosis and fractures.

Bone mineralization in children with Wilson's disease.

The goal of this study was to determine bone mineralization in children with Wilson's disease (WD). Twenty-seven patients (16 males) and two age- and gender-matched healthy children for each patient were enrolled in the study. Bone mineral content (BMC, grams) and density (BMD, g/cm(2)) at lumbar 1-4 vertebrae were measured by dual-energy X-ray absorptiometry. Urinary calcium excretion was calculated in 19 patients. The effect of cirrhosis and hypercalciuria on BMC and BMD was also evaluated in WD patients. There was no statistically significant difference between patients and healthy controls regarding mean BMC (33.0 ± 13.9 vs. 35.8 ± 13.8 g) (p = 0.940) and mean BMD values (0.66 ± 0.16 vs. 0.71 ± 0.18 g/cm(2)) (p = 0.269), respectively. Nine (47.4 %) patients had hypercalciuria. Hypercalciuric patients had statistically significant lower BMC and BMD values than those without hypercalciuria. A significant difference continued to be present after age, weight, height, and pubertal stage adjustment was done, but disappeared after weight, height, follow up duration, and pubertal stage adjustment was done. The presence of cirrhosis did not affect BMC and BMD significantly in WD patients. BMC and BMD in children with WD were normal. The presence of hypercalciuria but not cirrhosis may affect BMC and BMD negatively in the patients.

Hormonal and biochemical parameters correlated with bone densitometric markers in prepubertal Hungarian children

BackgroundThe conditions that define bone development in prepuberty profoundly influence bone health later in life. We aimed to reveal important determinants of bone mass in Tanner stage I. MethodsWe studied 84 healthy children (43 girls and 41 boys) aged 7 to 11years. Serum estradiol (E2), 25-hydroxyvitamin D3-vitamin [25(OH)D3], intact parathyroid hormone (PTHi), osteocalcin (OC) and β-crosslaps (CTXs) were longitudinally analyzed (Roche Diagnostics System). Total and spine bone mineral content (tBMC and LBMC) and density (tBMD and LBMD) were assessed, and total fat body mass index (FBMi) was calculated (DXA Lunar Prodigy). ResultsThe serum PTHi, OC and LBMD values were significantly higher in girls than in boys. The mean 25(OH)D3 level was lower but not significantly in girls compared to boys. Significant negative correlation was found between PTHi and 25(OH)D3 levels (r=−0.28; p=0.011) when tested in all subjects, but no correlation was detected when the gender groups were separately tested. There was a trend for higher E2 levels in girls. Significant positive correlation (r=0.32; p=0.042) was detected between FBMi and E2 concentration in girls only. A significant negative correlation was found between E2 and 25(OH)D3 levels (r=−0.37, p<0.05) in girls with elevated (>3.6pmol/l) PTHi and with suboptimal (<75nmol/l) 25(OH)D3 levels. Furthermore, positive correlations were noted between E2 and CTXs and OC (r=0.54, p<0.01 and r=0.39, p<0.03) and a marginally significant positive correlation (r=0.33; p=0.06) was detected between OC and PTHi levels in girls. However, we detected no correlations when these markers were analyzed in boys. There was a significant correlation between E2 and all BMC and LBMD values in both genders. The tBMD, LBMD and tBMC values showed weak, but significant negative associations with 25OHD3 levels (β=−0.44 to −0.55; p<0.001) in girls only. All BMD and BMC values were positively predicted by OC levels, but not by CTXs, in both genders. Among the biochemical markers, E2 was the only factor correlating with all dependent variables (BMCs and BMDs) in both genders. Among all parameters analyzed, FBMi (β=0.64) showed the strongest influence on tBMC characteristically in girls only. ConclusionsOur results support that 1.) E2 levels play a key role in defining bone turnover and bone mass in both genders already in prepuberty; 2.) high PTHi levels in childhood should be evaluated with caution, because the normal range for serum PTHi in different Tanner stage groups is not well established; and 3.) the negative correlation between 25(OH)D and E2 and the positive correlation between PTHi and OC suggest that estrogens regulate PTHi indirectly and cause lower circulating 25(OH)D3 levels. We propose that the decreased levels of 25(OH)D3 reflect not the real vitamin supply, but may rather be the result of E2 regulation. Therefore, the actual serum 25OHD levels may underestimate the availability of factors supporting bone formation.

Participation In A Community-based Running Program Is Associated With Higher Hip Bmc In Young Girls

Girls on the Run (GOTR) is a community-based running program that encourages social, mental, emotional and physical development in young girls through the process of training for a 5k running event. Previous reports have shown that GOTR has positive effects on self esteem and dietary behaviors; whether GOTR influences physiological outcomes is unknown. PURPOSE: To determine if participation in GOTR is associated with positive skeletal development in 8-12 year-old girls. METHODS: Girls (n=31; 9.8±1.4 yrs) were recruited from seven different GOTR Willamette Valley sites to form the intervention group. Girls who did not participate in GOTR or other organized physical activity formed the control group (n=11; 9.6±0.73 yrs). All girls completed a standard health history questionnaire at baseline. Weight, height, and time spent in moderate to vigorous physical activity (MVPA) were measured at baseline, 3, 6, and 9 months. MVPA was measured by accelerometry over a 7-day period at each time point. Bone mineral content (BMC (g/cm2); assessed using DXA) and nutrient intakes (assessed using the Youth Adolescent Food Frequency Questionnaire) were evaluated at baseline and 9-months. To determine baseline differences between groups in BMC outcomes, ANCOVA was used adjusting for age, height, weight, maturation status (years from peak ht. velocity), nutrient intakes and MVPA. The ANCOVA was repeated at 9-months adding initial BMC values to determine differences in BMC outcomes between groups at follow-up. RESULTS: At baseline GOTR participants had higher BMC at the femoral neck (FN) site compared to controls (mean + SE; 2.68 + 0.06 vs. 2.33 + 0.12; p=0.02); there were no baseline differences at any other bone site (p>0.05). At 9-months, GOTR participants had higher FN BMC (p=0.048) and higher trochanteric BMC (p=0.039) compared to controls after adjusting for growth, diet, activity and initial BMC values. There were no group differences at any other bone site (P>0.05). CONCLUSIONS: After adjusting for growth, maturation, diet, MVPA, and initial BMC values, we found that GOTR participants exhibited higher FN and trochanteric BMC compared to controls. Thus there appears to be a positive association between participation in GOTR and skeletal development at the hip in growing girls.

Denosumab, a fully human RANKL antibody, reduced bone turnover markers and increased trabecular and cortical bone mass, density, and strength in ovariectomized cynomolgus monkeys

Denosumab is a fully human monoclonal antibody that inhibits RANKL, a protein essential for osteoclast formation, function, and survival. Osteoclast inhibition with denosumab decreased bone resorption, increased bone mineral density (BMD), and reduced fracture risk in osteoporotic women. The effects of 16months of continuous osteoclast inhibition on bone strength parameters were examined in adult ovariectomized (OVX) cynomolgus monkeys (cynos). One month after surgery, OVX cynos (n=14-20/group) were treated monthly with subcutaneous vehicle (OVX-Veh) or denosumab (25 or 50mg/kg). Sham-operated controls were treated with vehicle (n=17). OVX-Veh exhibited early and persistent increases in the resorption marker CTx, followed by similar increases in the formation marker BSAP, consistent with increased bone remodeling. Denosumab reduced CTx and BSAP throughout the study to levels significantly lower than in OVX-Veh or Sham-Veh, consistent with reduced remodeling. Increased remodeling in OVX-Veh led to absolute declines in areal BMD of 4.3-7.4% at the lumbar spine, total hip, femur neck, and distal radius (all p<0.05 vs baseline). Denosumab significantly increased aBMD at each site to levels exceeding baseline or OVX-Veh controls, and denosumab significantly increased cortical vBMC of the central radius and tibia by 7% and 14% (respectively) relative to OVX-Veh. Destructive biomechanical testing revealed that both doses of denosumab were associated with significantly greater peak load for femur neck (+19-34%), L3-L4 vertebral bodies (+54-55%), and L5-L6 cancellous cores (+69-82%) compared with OVX-Veh. Direct assessment of bone tissue material properties at cortical sites revealed no significant changes with denosumab. For all sites analyzed biomechanically, bone mass (BMC) and strength (load) exhibited strong linear correlations (r(2)=0.59-0.85 for all groups combined). Denosumab did not alter slopes of load-BMC regressions at any site, and denosumab groups exhibited similar or greater load values at given BMC values compared with OVX-Veh or Sham. In summary, denosumab markedly reduced biochemical markers of bone remodeling and increased cortical and trabecular bone mass in adult OVX cynos. Denosumab improved structural bone strength parameters at all sites analyzed, and strength remained highly correlated with bone mass. There was no evidence for reduced material strength properties of cortical bone with denosumab over this time period, which approximates to 4years of remodeling in the slower-remodeling adult human skeleton. These data indicate that denosumab increased bone strength by increasing bone mass and preserving bone quality.

Bone mineral content is positively correlated to n-3 fatty acids in the femur of growing rats

The present study was conducted to determine whether provision of preformed dietary docosapentaenoic acid (DPAn-6) can replace DHA for normal long bone growth as assessed by dual-energy X-ray absorptiometry for mineral content (BMC). A newly modified artificial rearing method was employed to generate n-3 fatty acid-deficient rats. Except the dam-reared (DR; 3.1 % alpha-linolenic acid) group, newborn pups were separated from their mothers at age 2 d and given artificial rat milk containing linoleic acid (LA), or LA supplemented with 1 % DHA (22 : 6n-3; DHA), 1 % DPAn-6 (DPA), or 1 % DHA plus 0.4 % DPAn-6 (DHA/DPA). The rats were later weaned onto similar pelleted diets. At adulthood, the rats were euthanised and bones (femur, tibia, and lumbar vertebrae) collected for tissue fatty acid analysis and bone mineral density (BMD) determination. The analyses showed that long bones such as femur and tibia in DPAn-6-treated rats contained higher DPAn-6 content and generally had the lowest BMC and BMD values. Hence, DPAn-6 did not replace DHA for normal bone growth and maximal BMC in femur, indicating an indispensible role of DHA in bone health. In conclusion, DHA accumulates in the osteoblast-rich and nerve-abundant periosteum of femur; DHA but not EPA appears to be a vital constituent of marrow and periosteum of healthy modelling bone; and both DHA and total n-3 PUFA strongly correlate to BMC.

Dual-Energy X-ray Absorptiometry Assessment of Tibial Mid-third Bone Mineral Density in Young Athletes

We suggested a new reproducible method to measure densitometric values at mid-third part of the tibia by dual-energy X-ray absorptiometry (DXA; Delphi, Hologic ®, Waltham, MA) in a population of young adults. Our population was composed of 170 subjects aged 22.7 ± 4.0 yr: athlete men (n = 67) and women (n = 40); control men (n = 33) and women (n = 30). Athletes practiced collective sports, judo or weightlifting for 10.0 ± 3.6 h/wk. We measured bone area (cm 2), bone mineral content (BMC, g), and bone mineral density (BMD,g/cm 2) at the left total hip and the mid-third part of the tibia with DXA. For the tibia scan, we used the whole body mode. To ensure the reproducibility of the method, both legs were extended and the feet were maintained on a support in an internal rotation of 35°. The region of interest of the lumbar spine from the whole body scan was positioned around the mid-third part of the tibia. Area, BMC, and BMD values were significantly higher in athletes compared with those of controls. The intra- and interobserver variability of the image analysis were 0.38% and 1.01%, respectively. For BMD measurements, the short-term (4 scans/d) and mid-term (4 scans/mo) reproducibility were 1.33% and 1.94%, respectively. DXA is a suitable tool to evaluate densitometric measurements at the mid-third part of the tibia and the influence of physical activity on that bone site.

Adipocytokine and ghrelin levels in relation to bone mineral density in physically active older women: longitudinal associations

We investigated the relationship between the decrease in bone mineral mass (BMC) and bone mineral density (BMD) values with baseline adipocytokine and ghrelin concentrations in physically active postmenopausal women. Leptin, adiponectin, ghrelin, BMC, BMD and different body composition values were measured in 35 women (age: 69.7+/-6.0 years) before and after a 12-month prospective study period. Significant (P<0.05) decreases in fat-free mass (FFM) (by 2.56%) and BMC (by 1.63%) and increases in adiponectin (by 14.8%) were seen in older females as a result of the study period. The independent variables that were associated with decreases in total BMC were baseline fat mass (FM) and adiponectin explaining 30.6% (R(2)x100) of the total variance. In another model, baseline FFM and leptin were the independent variables that explained 20.6% (P<0.05) of the total variance in the decreases in total BMD value. The variables that were associated with decreases in femoral neck BMD were FM and leptin (R(2)=0.102; P<0.05), while the independent variables were baseline trunk fat:leg fat ratio and adiponectin in the model with decreases in lumbar spine BMD as the dependent variable, and accounted for 13.1% (P<0.05) of the decreases in BMD variance. Initial adiponectin concentration together with specific body composition characteristics predicted loss in BMC and lumbar spine BMD values, while initial leptin concentration together with specific body composition parameters determined the loss in total and femoral neck BMD values in physically active older women.

The influence of ghrelin, adiponectin, and leptin on bone mineral density in healthy postmenopausal women

The association of body fat mass (FM) with bone mineral mass (BMC) and bone mineral density (BMD) has been attributed to a mechanical load exerted on the skeleton by FM and by the effect of different hormones. The aim of the present study was to determine whether there is a relationship between ghrelin, adiponectin, and leptin with BMC and BMD in healthy postmenopausal women (n = 88; age, 68.9 +/- 6.8 years; body mass index, 27.4 +/- 3.6 kg/m(2)). Body composition, BMC, and BMD were derived by dual-energy X-ray absorptiometry. Waist-to-hip (WHR) and waist-to-thigh (WTR) ratios were also obtained. Ghrelin was associated with total BMC (beta = -0.945; P = 0.0001), total BMD (beta = -0.959; P = 0.0001), lumbar spine BMD (beta = -0.945; P = 0.0001), and femoral neck BMD (beta = -0.957; P = 0.0001), and remained associated (P < 0.041) in different analyses that controlled for measured body composition and hormonal and insulin resistance values. However, the associations between ghrelin and measured bone mineral values were no longer significant (P > 0.149) when adjusted for body fat distribution values (WHR, WTR). Adiponectin was significantly related to total BMC (beta = -0.931; P = 0.0001), total BMD (beta = -0.940; P = 0.0001), lumbar spine BMD (beta = -0.937; P = 0.0001), and femoral neck BMD (beta = -0.940; P = 0.0001) values, and these relationships remained significant (P < 0.019) after adjusting for measured body fat, hormonal, and insulin resistance values but not when adjusted for fat-free mass (FFM; P > 0.106). In addition, significant associations of leptin with total BMC (beta = 0.912; P = 0.0001), total BMD (beta = 0.907; P = 0.0001), lumbar spine BMD (beta = 0.899; P = 0.0001), and femoral neck BMD (beta = 0.906; P = 0.0001) were found. These associations remained significant (P < 0.010) in different analyses that controlled for hormonal and insulin resistance values, but the associations between leptin and bone mineral values were no longer significant (P > 0.145) when adjusted for specific body composition values (WHR, WTR, FM, and FFM). In conclusion, it appears that the influence of plasma ghrelin, adiponectin, and leptin levels on BMC and BMD values is mediated or confounded by the specific body composition parameters in healthy postmenopausal women.

Effect of WBV Exercise on Bone Remodeling in Ovariectomized Rats

Physical exercise is recommended for the prevention and treatment of osteoporosis. The present study evaluated the influence of WBV exercise on the bone formation and bone remodeling in an ovariectomized animal model. PURPOSE: The aim of this study is to investigate potential possibility for activation of bone formation and decrease of bone loss while whole body vibration exercise(frequency: 45Hz, vertical acceleration: 0.3g, 5days/wk, for 12wks) was performed. METHODS: OPG concentration, RANKL concentration and RANKL/OPG ratio from bone marrow stromal cell were evaluated and DXA from the femur bone was measured. The Sprague-Dawley rats have been divided into 4 groups (Sham-operated control; Shamoperated WBV exercise). RESULTS:To compare the 4 groups(2×2) statistically, tow-way ANOVA was used. Statistical significant value was p<.05. Vibrating exercise groups showed significantly higher OPG concentration(p<.001), RANKL concentration(p<.05), BMD(p<.001), BMC(p<.001) and bone area(p<.01) values compared to control groups. The other side RANKL/OPG ratio was lower in WBV exercise groups(p<.05) significantly. CONCLUSION: These present results indicate that WBV exercise is effective method for activating bone formation and preventing early post-ovariectomy bone loss. These also can be explained that WBV exercise increase bone mass and bone strength in an animal model.

Vitamin K epoxide reductase complex subunit 1 (Vkorc1) haplotype diversity in mouse priority strains

BackgroundPolymorphisms in the vitamin K-epoxide reductase complex subunit 1 gene, Vkorc1, could affect blood coagulation and other vitamin K-dependent proteins, such as osteocalcin (bone Gla protein, BGP). Here we sequenced the Vkorc1 gene in 40 mouse priority strains. We analyzed Vkorc1 haplotypes with respect to prothrombin time (PT) and bone mineral density and composition (BMD and BMC); phenotypes expected to be vitamin K-dependent and represented by data in the Mouse Phenome Database (MPD).FindingsIn the commonly used laboratory strains of Mus musculus domesticus we identified only four haplotypes differing in the intron or 5' region sequence of the Vkorc1. Six haplotypes differing by coding and non-coding polymorphisms were identified in the other subspecies of Mus. We detected no significant association of Vkorc1 haplotypes with PT, BMD and BMC within each subspecies of Mus. Vkorc1 haplotype sequences divergence between subspecies was associated with PT, BMD and BMC.ConclusionPhenotypic variation in PT, BMD and BMC within subspecies of Mus, while substantial, appears to be dominated by genetic variation in genes other than the Vkorc1. This was particularly evident for M. m. domesticus, where a single haplotype was observed in conjunction with virtually the entire range of PT, BMD and BMC values of all 5 subspecies of Mus included in this study. Differences in these phenotypes between subspecies also should not be attributed to Vkorc1 variants, but should be viewed as a result of genome wide genetic divergence.