Elemental anomalies in hair as indicators of endocrinologic pathologies and deficiencies in calcium and bone metabolism

Analytical results obtained by ICP-MS of hair samples from a group of women from Rio de Janeiro city show that abnormal Ca and P concentrations in this compartment can be an indication of pathologies affecting the metabolism of these elements. The study was conducted initially on 900 women (outpatients, >40 years). From this group, approx. 24% showed anomalously high or low Ca concentrations in hair, in some cases correlated to anomalies of other elements. In 144 cases (16%), very high concentrations of Ca (up to 8,285 mg/kg) were measured, frequently correlated with a high concentration of P (up to 4,720 mg/kg), exceeding by far the reference intervals for this age/sex group. Follow-up studies of a few individuals from this group gave first indications that their abnormal hair compositions were related to endocrinologic pathologies affecting calcium/bone metabolism. Very low hair Ca-concentrations were observed in older women (72 cases, age >60 years) and related to senile osteoporosis. Complementary investigations of patients with recognized endocrinologic pathologies (hyperthyroidism, hyper- and hypoparathyroidism) and osteomalacia gave statistical support for the hypothesis that hair concentrations of Ca, P and various other trace elements are influenced characteristically by these diseases. In patients with hyperparathyroidism and hyperthyroidism, both elements showed significant increase in hair, whereas patients with rickets/osteomalacia had only elevated Ca concentrations, together with suspiciously high toxic levels of Cd and various other elements (Fe, Mn, Mg, Sr, Ba). Patients with hypoparathyroidism had significantly decreased Ca and P concentrations in hair. Statistical evaluation of these data by multivariant analysis (MANOVA) using a contrast matrix and by discriminant analysis showed that elemental hair anomalies can be used to diagnose correctly the above-mentioned pathologies, demonstrating the usefulness of hair analysis as a complementary tool for the detection of disturbances in calcium/bone metabolism.     

Correlation Analysis Between Bone Mineral Density and Serum Element Contents of Postmenopausal Women in Xi’an Urban Area

The objective of this paper is to investigate the correlation between serum macro-element and trace element contents and bone mineral density (BMD) as well as the occurrence of osteoporosis. After the epidemiological investigation of 290 postmenopausal women from ages 45 to 65 in the Xi’an urban area, their blood was collected and serum concentrations of macro-elements, calcium, phosphonium, potassium, sodium, magnesium, and trace elements, zinc, iron, copper, and selenium were determined using atomic absorption spectrometry. Their BMD was measured by QDR-2000 dual-energy X-ray absorptiometry (DEXA). The correlation analysis between BMD and serum element contents was done with the software of SPSS 13.0. The correlation analysis of serum elements of postmenopausal women showed that there was a significant correlation between serum calcium and the other elements, and also a significant correlation between serum phosphonium and the others except serum potassium. The serum potassium content had a significant correlation with serum calcium, sodium and iron, but sodium content showed a significant correlation with the others except iron and selenium. In addition, copper had a significant correlation with the others except potassium and selenium. In correlation analysis between BMD and the elements contents, only did the potassium content show a significant positive correlation with BMD of lumbar vertebra and proximal femora. The comparison results between osteoporosis group, osteopenia group, and healthy group showed that there was no significant difference in the element contents between the groups, but there existed a tendency that potassium content increased with the rise of BMD. There exist significant correlations between the contents of serum elements such as calcium, phosphonium, sodium, potassium, magnesium, zinc, iron, copper, and selenium, but no significant differences in these elements contents between the osteoporosis group, osteopenia group, and healthy group. Serum potassium content shows a significant positive correlation with BMD, suggesting potassium may be involved in the development of osteoporosis in postmenopausal women.     

Predicting changes in mechanical properties of trabecular bone by adaptive remodeling

Because changes in the mechanical properties of bone are closely related to trabecular bone remodeling, methods that consider the temporal morphological changes induced by adaptive remodeling of trabecular bone are needed to estimate long-term fracture risk and bone quality in osteoporosis. We simulated bone remodeling using simplified and pig trabecular bone models and estimated the morphology of healthy and osteoporotic cases. We then displayed the fracture risk of the remodeled models based on a cumulative histogram from high stress. The histogram showed more elements had higher stresses in the osteoporosis model, indicating that the osteoporosis model had a greater risk.     

Ca/P concentration ratio at different sites of normal and osteoporotic rabbit bones evaluated by Auger and energy dispersive X-ray spectroscopy

Osteoporosis is a systemic skeletal disorder associated with reduced bone mineral density and the consequent high risk of bone fractures. Current practice relates osteoporosis largely with absolute mass loss. The assessment of variations in chemical composition in terms of the main elements comprising the bone mineral and its effect on the bone’s quality is usually neglected. In this study, we evaluate the ratio of the main elements of bone mineral, calcium (Ca), and phosphorus (P), as a suitable in vitro biomarker for induced osteoporosis. The Ca/P concentration ratio was measured at different sites of normal and osteoporotic rabbit bones using two spectroscopic techniques: Auger electron spectroscopy (AES) and energy-dispersive X-ray spectroscopy (EDX). Results showed that there is no significant difference between samples from different genders or among cortical bone sites. On the contrary, we found that the Ca/P ratio of trabecular bone sections is comparable to cortical sections with induced osteoporosis. Ca/P ratio values are positively related to induced bone loss; furthermore, a different degree of correlation between Ca and P in cortical and trabecular bone is evident. This study also discusses the applicability of AES and EDX to the semiquantitative measurements of bone mineral’s main elements along with the critical experimental parameters.     

Bone tissue changes in rats during prolonged restriction of motor activity

The objective of this investigation was to measure the effect of prolonged restriction of motor activity (hypokinesia) of rats on the mass, density, mineral composition, reconstruction parameters and elemental composition of their bone tissue. The studies were done during 90 days of hypokinesia (HK) on 90 male Wistar rats equally divided into two groups: (1) vivarium control rats (VCR) and (2) hypokinetic rats (HKR). For the simulation of the hypokinetic effect the HKR group was kept for 90 days in small individual cages made of wood that restricted the movements of rats in all directions without hindering food and water intakes. During the prehypokinetic period of 15 days and during the hypokinetic period of 90 days bone mass, bone density, bone calcium and phosphorus concentrations, bone reconstruction parameters and elemental composition of bones were determined. During the same periods food intake and body weight losses were also measured. In the HKR group signs of osteoporosis in the spongy structures of the tubular bones were observed; they also showed significant decrease in rat femur weight, and in cross section of the rat femur, and in mineral concentrations of the femoral head when compared with the VCR group. The HKR group also show a significant decrease in food intake and body weight when compared with the VCR group. The corresponding parameters did not change significantly in the VCR group when compared with the baseline control values. It was concluded that prolonged exposure to HK induced osteoporosis and structural changes in bones. This apparently occurred due to inhibition of bone tissue formation in the HKR group.     

降钙素对骨质疏松大鼠骨密度形态计量学与骨代谢的影响

目的探讨降钙素(密盖息)对骨质疏松大鼠骨密度、骨形态计量学影响以及与血钙、磷、维生素D代谢和生长因子的关系。方法用摘除大鼠双侧卵巢的方式制备骨质疏松模型(OVX),实验动物分为4个组:模型对照组、密盖息治疗组,盐酸雷洛昔芬治疗组,假手术组。应用HOLOGIC第4代双能X线4500W骨密度仪测定大鼠腰椎、股骨上段骨密度值(BMD);以骨形态计量学测股骨骨小梁面积、矿化沉积率;用ELISA法测定血清IGF-1水平和血清25OHVitD浓度以及血淋巴细胞维生素D受体(VDR)含量。结果密盖息治疗组、盐酸雷洛昔芬治疗组均较OVX组腰椎、股骨上段骨密度增高,组间比较差异有显著性(P<0.01)。密盖息治疗组较盐酸雷洛昔芬治疗组股骨上段骨密度增高,两组之间差异有显著性(P<0.01)。密盖息治疗组骨小梁面积明显增加、矿化沉积率增高。密盖息治疗组、盐酸雷洛昔芬治疗组血清IGF-1浓度值、血清25-OHVitD浓度值升高,与OVX组比较差异有显著性(P<0.01)。各组血淋巴细胞VDR含量无明显变化,与OVX组比较差异无显著性(P>0.05)。结论密盖息能够预防腰椎、股骨上段骨密度丢失,使骨小梁面积明显增加、矿化沉积率增高并且血清IGF-1及血清25-OHVitD浓度值升高,但对VDR含量无明显作用。     

Osteoporosis influences the late period of fracture healing in a rat model prepared by ovariectomy and low calcium diet

To elucidate the influence of osteoporosis on the fracture healing, we produced a rat osteoporosis model by ovariectomy and by maintaining a low calcium diet; and monitored the healing process radiographically, histologically, and biomechanically for 12 weeks. Radiologic, histologic and biomechanical findings of the fracture areas 6 weeks after making the fractures were almost identical in both the osteoporosis group and the control group. However, 12 weeks after making the fractures, newly generated bones in the osteoporosis group showed histological osteoporotic changes and their bone mineral density on the fracture site decreased. These findings show that estrogen-deficient and low calcium conditions greatly affect the bone in the later period of the healing process, but do not affect remarkably the early healing period. This is clinically important when we consider fracture treatments for patients with osteoporosis due to menopause.     

Effects of a calcium/vitamin D/Zinc combination on anti-osteoporosis in ovariectomized rats

BackgroundOsteoporosis is a major health problem in postmenopausal women, and characterized by deteriorated bone mass and micro-architecture. There have been some clinical trials demonstrating the beneficial effects of vitamin-D and some trace elements on calcium absorption and attenuation of osteoporosis development. However, effects of the combination of vitamin-D and zinc on calcium absorption and osteoporosis have not been adequately investigated.MethodsNetwork pharmacology was first performed to explore possible correlations between calcium/vitamin D/zinc and osteoporosis. Forty-nine female Sprague-Dawley rats (6 months old, 250 ± 20 g) were randomized into 7 experimental groups with 7 animals per group for the in vivo study, including one sham surgery control group, one ovariectomizing (OVX) group, and 5 OVX plus treatment groups. At the end of animal experiment, animal tibia and femur leg bones and blood were collected for H&E staining, bone microstructure analysis by a micro-CT, measurement of bone and serum Ca, P and Zn concentrations, and immunohistochemical detection of macrophage-colony stimulating factor receptor (M-CSFR) and receptor activator of nuclear factor-kappa B ligand (RANKL).ResultsThe network pharmacology analysis identified 57 candidate targets that were related to the osteoporosis-Ca/VitD/Zn interconnections. Further pathway analysis suggested that the combined treatment of Ca, VitD and Zn attenuated osteoporosis via modulation of metabolic pathways. We found that a therapy with Ca/VitD-M/Zn-M (73 mg/kg/day Ca, 0.6 g/kg/day VitD3 and 0.6 mg/kg/day zinc citrate) could significantly suppress the progression of osteoporosis in rats. After the Ca/VitD-M/Zn-M treatment, the ratio of bone volume/tissue volume, trabecular number and the trabecular thickness were all significantly elevated while the extent of trabecular separation was significantly reduced. Additionally, both serum calcium and bone calcium levels were significantly upregulated by the Ca/VitD/Zn treatment in a dose-dependent manner. The combination of Ca/VitD-M/Zn-M was superiou to either Ca/VitD-L/Zn-L or Ca/VitD-H/Zn-H treatment for such an effect. Moreover, the osteoporosis-associated M-CSFR and RANKL factors were both significantly downregulated by the Ca/VitD-M/Zn-M treatment in bone tissues of OVX rats.ConclusionsThe combined supplement of VitD and Zn facilitates the Ca(2 +) absorption and attenuates the development of osteoporosis via down-regulation of osteoporosis-associated factors M-CSFR and RANKL, thus potentially constitutes an alternative therapy for the postmenopausal osteoporosis.     

Synchrotron ultraviolet microspectroscopy on rat cortical bone: involvement of tyrosine and tryptophan in the osteocyte and its environment

Alcohol induced osteoporosis is characterized by a bone mass decrease and microarchitecture alterations. Having observed an excess in osteocyte apoptosis, we aimed to assess the bone tissue biochemistry, particularly in the osteocyte and its environment. For this purpose, we used a model of alcohol induced osteoporosis in rats. Bone sections of cortical bone were investigated using synchrotron UV-microspectrofluorescence at subcellular resolution. We show that bone present three fluorescence peaks at 305, 333 and 385 nm, respectively corresponding to tyrosine, tryptophan and collagen. We have determined that tyrosine/collagen and tryptophan/collagen ratios were higher in the strong alcohol consumption group. Tryptophan is related to the serotonin metabolism involved in bone formation, while tyrosine is involved in the activity of tyrosine kinases and phosphatases in osteocytes. Our experiment represents the first combined synchrotron UV microspectroscopy analysis of bone tissue with a quantitative biochemical characterization in the osteocyte and surrounding matrix performed separately.     

不同程度老年骨质疏松患者血清BALP、OPG/PYR比值变化及其与骨密度、骨折发生的相关性分析

摘要 目的：分析不同程度老年骨质疏松患者血清骨特异性碱性磷酸酶(BALP)、骨保护素(OPG)/吡啶啉(PYR)比值变化及其与骨密度、骨折发生的相关性。方法：选择我院自2020年11月至2023年7月接诊的70例老年骨质疏松患者作为观察组,其中轻-中度骨质疏松44例、重度骨质疏松26例;另选70例老年非骨质疏松者作为对照组。检测所有受试者血清BALP、OPG/PYR比值、腰椎、股骨颈和髋部的骨密度(BMD),分析BALP、OPG/PYR比值与不同骨骼部位BMD的关系,使用受试者工作特征(ROC)曲线分析BALP、OPG/PYR比值对老年骨质疏松骨折的预测效能。结果：观察组血清BALP水平高于对照组,OPG/PYR比值小于对照组（P＜0.05）;重度骨质疏松组血清BALP水平高于轻-中度骨质疏松组,OPG/PYR比值小于轻-中度骨质疏松组（P＜0.05）;观察组腰椎、股骨颈及髋部的BMD均小于对照组（P＜0.05）;经Pearson相关性分析,腰椎、股骨颈及髋部的BMD与血清BALP水平呈负相关（P＜0.05）,与OPG/PYR比值呈正相关（P＜0.05）;经ROC曲线分析,血清BALP联合OPG/PYR比值预测老年骨质疏松骨折的AUC为0.890。结论：老年骨质疏松患者血清BALP水平升高、OPG/PYR比值减小,与病情严重程度及骨密度有关,联合预测骨折的效能较好,值得进一步研究应用。     

Bone density parathyroid hormone and 25-hydroxyvitamin D concentrations in middle aged women.

OBJECTIVE--To examine the relation between bone density and indices of calcium metabolism including parathyroid hormone and 25-hydroxyvitamin D concentrations in middle aged women. DESIGN--A cross sectional study. SETTING AND SUBJECTS--138 women volunteers aged 45-65 with no known osteoporosis and unselected for disease status recruited for a dietary assessment study from the community using general practice registers. Volunteer rate was 20%. MAIN OUTCOME MEASURE--Bone mineral density measured with dual energy x ray absorptiometry. RESULTS--Bone density at the lumbar spine and neck and trochanteric regions of the femur was inversely related to serum intact parathyroid hormone concentrations and positively related to serum 25-hydroxyvitamin D concentrations. These associations were independent of possible confounding factors, including age, body mass index, cigarette smoking habit, menopausal status, and use of diuretics and postmenopausal hormone replacement therapy. These associations were apparent throughout the whole distribution of bone density and 25-hydroxyvitamin D and parathyroid hormone concentrations within the normal range, suggesting a physiological relation. CONCLUSIONS--The findings are consistent with the hypothesis that parathyroid hormone and 25-hydroxyvitamin D concentrations influence bone density in middle aged women. Findings from this study together with other work suggest that the role of vitamin D in osteoporosis should not be neglected. The associations with parathyroid hormone also indicate plausible biological mechanisms. The roughly 5-10% difference in bone density between top and bottom tertiles of serum 25-hydroxyvitamin D concentrations, though not large in magnitude, may have considerable public health implications in terms of prevention of osteoporosis and its sequelae, fractures.     

Measurement of bone mineral density (BMD) with quantitative computed tomography (QCT) in postmenopausal osteoporosis: effect of estrogen.

To determine the efficacy of the estrogen replacement therapy (ERT) on the bone mineral density (BMD) measured with quantitative computed tomography (QCT) in postmenopausal osteoporosis 16 women aged 46-72 were examined. They were divided into two groups: 8 women treated with conjugated estrogens (Group I) and 8 who did not received ERT (Group II). In all 16 patients the serum hormonal concentrations (LH, FSH and estradiol) were measured with radioimmunological methods. The bone densitometry was performed in all of them using the single-energy computed tomography (QCT) with the computer Picker 1200. Bone mineral density was measured in three lumbar vertebra (L1-L3) and expressed in milligrams K2HPO4 per ml. The bone mineral density (BMD) was statistically significantly higher in the estrogen treated group (Group I) in every vertebra compared with that of controls (Group II). The serum FSH concentration was statistically significantly lower in the ERT group (Group I) and a statistically significant correlation between FSH level and average BMD (Lmean) was present. In conclusion: 1. the ERT is very efficacious in preventing bone loss in postmenopausal women; 2. measurement of BMD in lumbar vertebra L1 or L3 may be a sufficiently reliable and accurate, cost-effective and time-saving method of screening for osteoporosis; 3. the serum FSH determination seems to be useful in monitoring of the estrogen therapy for postmenopausal osteoporosis.     

绝经期女性血脂及血压水平与糖尿病骨质疏松的关系

目的：探讨绝经期女性血脂及血压与糖尿病骨质疏松发生的关系。方法：选取2014 年3 月-2015 年5 月在我院接受治疗的 绝经期女性糖尿病患者100 例作为研究对象,根据骨密度不同将患者分为骨质疏松组和非骨质疏松组。检测并比较两组研究对 象的血脂及血压水平,分析其与骨质疏松发生的关系。结果：骨质疏松组患者总胆固醇（TC）、三酰甘油（TG）、高密度脂蛋白胆固 醇（HDL-C）及低密度脂蛋白胆固醇（LDL-C）水平均高于非骨质疏松组,差异具有统计学意义（P<0.05）;与非骨质疏松组比较,骨 质疏松组患者舒张压（DBP）升高,而收缩压（SBP）降低,差异具有统计学意义（P<0.05）;Pearson相关性分析结果显示,年龄、总胆 固醇（TC）及低密度脂蛋白胆固醇（LDL-C）与双股骨骨密度呈正相关关系（P＜0.05）,与腰椎骨密度呈负相关关系（P＜0.05）;Logistic 回归分析结果显示,年龄、总胆固醇（TC）、低密度脂蛋白胆固醇（LDL-C）及收缩压（SBP）是糖尿病骨质疏松发生的危险因素 （P<0.05）。结论：绝经期女性糖尿病患者的年龄、总胆固醇、LDL-C 及收缩压与骨质疏松密切相关,临床应给予重视并采取有效措 施进行预防。     

Osteoporosis and trace elements--an overview

More than 200 million people are affected by osteoporosis worldwide, as estimated by 2 million annual hip fractures and other debilitating bone fractures (vertebrae compression and Colles' fractures). Osteoporosis is a multi-factorial disease with potential contributions from genetic, endocrine functional, exercise related and nutritional factors. Of particular considerations are calcium (Ca) status, vitamin D, fluoride, magnesium and other trace elements. Several trace elements such as zinc and copper are essential for normal development of the skeleton in humans and animals. Fluoride accumulates in new bone and results in a net gain in bone mass, but may be associated with a tissue of poor quality. Aluminum induces impairment of bone formation. Gallium and cadmium suppresses bone turnover. However, exact involvements of the trace elements in osteoporosis have not yet been fully clarified. Numerous investigators have evaluated the role of medications and supplementations with minerals and trace substances to reverse the progression of this disease. Although bisphosphonates are still the drugs of choice, low-dosed fluoride and strontium salts have shown promise for the future.     

Age-related cortical bone loss in women from a 3rd-4th century AD population from England

Age-dependent cortical bone loss in adult females from a skeletal assemblage from 3rd-4th century AD England was studied using metacarpal radiogrammetry. Results showed reduced peak cortical bone thickness compared with modern subjects, and the magnitude of cortical bone loss in older females compared with their younger counterparts was greater than that documented for a modern reference population. An elevated prevalence of fractures classically associated with osteoporosis was also observed in the over-50-year cohort. The severity of osteoporosis in this group is difficult to explain in terms of extraneous factors relating to 3rd-4th century lifestyles. Given the important genetic component in osteoporosis, the results may indicate some inherent susceptibility in this particular population to the disease, and ways in which this possibility might be further explored are suggested.     

PIXE study on the effects of parathyroid hormone on elemental content in rat bones

Parathyroid hormone (PTH) has attracted considerable interest as a bone anabolic agent. PTH plays a central role in regulating calcium phosphate metabolism and its increases in production in response to low serum calcium levels. A continuous hypersecretion of PTH, as occurs in primary hyperparathyroidism, leads to bone resorption. In this study, the effect of different doses of parathyroid hormone (PTH) on bone mineral content (BMC) in rats was investigated by particle-induced X-ray emission (PIXE). This study will help in investigating further the toxicity of extremely high doses of PTH on BMC. For this study, PTH at doses of 15, 45, or 135 μg/kg/day were applied to 9-month-old male and female Sprague Dawley (SD) rats. The concentrations of calcium (Ca), phosphorus (P), strontium (Sr), and zinc (Zn) were measured for bone treatment of PTH. From the results of the research, it was revealed that the biomechanical characteristics of the bone as well as the bone mass were enhanced after the treatment. It was further found that the concentrations of other elements also increased, excluding Zn. This research proved that PTH assists in the treatment of osteoporosis as revealed by the characteristics of different elements. PIXE can be used to determine the concentrations of bone mineral content.     

An NMR Metabolomic Study on the Effect of Alendronate in Ovariectomized Mice

Alendronate sodium (Fosamax) is most widely used for the prevention and treatment of osteoporosis. It is a type of anti-resorptive agent that reduces the risk of fractures by changing bone turnover and bone mineral density. We investigated the effect of Fosamax on a mouse model of osteoporosis. Twenty-seven female C57BL/6JNarl mice were divided into three groups: sham, ovariectomized (OVX) and OVX + Fosamax (Fosamax). After 23 weeks, bone density of femurs was analyzed using microcomputed tomography (micro-CT), and serum was analyzed for osteoblast and osteoclast activity, as well as metabolites using nuclear magnetic resonance (NMR) spectroscopy. Fosamax increased bone mineral density and cortical bone thickness, and decreased osteoblast activity slightly. Fosamax did not significantly change osteoclast activity. Serum metabolomics revealed that Fosamax had profound effects on overall metabolism, as significantly higher concentrations of metabolites associated with energy metabolism (including TCA-cycle intermediates and glucose), 3-hydroxybutyrate, taurine, allantoin, acetate, and ethanol, as well as lower concentrations of aspartate were observed in the Fosamax-treated mice compared with the OVX mice. These results suggest that alendronate may work by increasing bone density through altered metabolic activity.     

Polar bears (Ursus maritimus), the most evolutionary advanced hibernators, avoid significant bone loss during hibernation

Some hibernating animals are known to reduce muscle and bone loss associated with mechanical unloading during prolonged immobilisation,compared to humans. However, here we show that wild pregnant polar bears (Ursus maritimus) are the first known animals to avoid significant bone loss altogether, despite six months of continuous hibernation. Using serum biochemical markers of bone turnover, we showed that concentrations for bone resorption are not significantly increased as a consequence of hibernation in wild polar bears. This is in sharp contrast to previous studies on other hibernating species, where for example, black bears (Ursus americanus), show a 3-4 fold increase in serum bone resorption concentrations posthibernation,and must compensate for this loss through rapid bone recovery on remobilisation, to avoid the risk of fracture. In further contrast to black bears, serum concentrations of bone formation markers were highly significantly increased in pregnant female polar bears compared to non-pregnant,thus non-hibernating females both prior to and after hibernation. However, bone formation concentrations in new mothers were significantly reduced compared to pre-hibernation concentrations. The de-coupling of bone turnover in favour of bone formation prior to hibernation, suggests that wild polar bears may posses a unique physiological mechanism for building bone in protective preparation against expected osteopenia associated with disuse,starvation, and hormonal drives to mobilise calcium for reproduction, during hibernation. Understanding this physiological mechanism could have profound implications for a natural solution for the prevention of osteoporosis in animals subjected to captivity with inadequate space for exercise,humans subjected to prolonged bed rest while recovering from illness, or astronauts exposed to antigravity during spaceflight.? 2008 Elsevier Inc. All rights reserved.     

Plasma Selenium, Zinc, Copper and Lipid Levels in Postmenopausal Turkish Women and Their Relation with Osteoporosis

It has been shown that the trace elements and lipids play role in the growth, development and maintenance of bones. We aimed to investigate serum selenium (Se), zinc (Zn), copper (Cu) and lipid (total cholesterol, triglyceride (TG), high density lipoprotein-cholesterol, low-density lipoprotein-cholesterol) levels in postmenopausal women with osteoporosis, osteopenia and in healthy controls, and to determine the relationship between Se, Zn, Cu and lipid parameters and bone mineral density (BMD). The study included 107 postmenopausal women; 35 healthy (group 1), 37 osteopenic (group 2) and 35 osteoporotic (group 3). The women in all three groups were carefully matched for body mass index (BMI). Serum concentrations of Se, Zn and Cu were measured by atomic absorption spectrophotometry. Plasma Se, Cu, Zn and lipid levels were similar in all groups (p?>?0.05). When we combined the women in each of the three groups, and considered them as one group (n?=?107) we found a positive correlation between BMI and lumbar vertebra BMD, femur neck BMD, femur total BMD; a positive correlation between TG and femur neck BMD, femur total BMD; a positive correlation between Zn and lumbar vertebra BMD (total T score) (p??0.05). Although BMI has a positive effect on BMD, trace elements and lipids, except Zn and TG, did not directly and correlatively influence BMD. Further studies are needed to clarify the role and relationship of trace elements and lipid parameters in postmenopausal osteoporosis.     

Regulation of bone mass, bone loss and osteoclast activity by cannabinoid receptors

Accelerated osteoclastic bone resorption has a central role in the pathogenesis of osteoporosis and other bone diseases. Identifying the molecular pathways that regulate osteoclast activity provides a key to understanding the causes of these diseases and to the development of new treatments. Here we show that mice with inactivation of cannabinoid type 1 (CB1) receptors have increased bone mass and are protected from ovariectomy-induced bone loss. Pharmacological antagonists of CB1 and CB2 receptors prevented ovariectomy-induced bone loss in vivo and caused osteoclast inhibition in vitro by promoting osteoclast apoptosis and inhibiting production of several osteoclast survival factors. These studies show that the CB1 receptor has a role in the regulation of bone mass and ovariectomy-induced bone loss and that CB1- and CB2-selective cannabinoid receptor antagonists are a new class of osteoclast inhibitors that may be of value in the treatment of osteoporosis and other bone diseases.