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Abstract: Background: Osteoblast-derived matrix metalloproteinse-1 (MMP-1), MMP-2 and tissue inhibitor of metalloproteinase-1 (TIMP-1) play a role in bone metabolism by degrading bone matrix. Methods: We measured MMP-1, MMMP-2, TIMP-1 and associated results with age and bone metabolism in 591 Chinese women aged 20–80 y. Results: Serum MMP-1, MMP-2, and TIMP-1 concentrations exhibited positive correlation with age. Serum concentrations of MMP-1 were higher in 40–69 y old women. The concentrations of MMP-2 were significantly increased in the 50–69 y olds. Serum TIMP-1 concentrations were significantly lower in women aged 30–59 y, and then these were followed by an increase at >60 y olds. We found a significant negative weaker correlation between MMP-2 and BMD. But multiple linear stepwise regression analysis showed that MMP-2 was not a determinant factor for BMD. There were significant positive correlations between MMP-2 and bone alkaline phosphatase (BAP), osteocalcin (OC), and cross-linked N-telopeptides of type I collagen (NTX). Conclusions: The serum concentrations of MMP-1, MMP-2, and TIMP-1 exhibit age-related changes, and circulating MMP-2 and bone turnover are related. [Copyright &y& Elsevier]

Objective. Recently our studies have shown that nylestriol in combination with levonorgestrel prevented bone loss, decreased bone turnover rate and increased the maximal loading of bone without obvious side effects in retinoic acid (RA) induced osteoporotic rats. In addition to the animal experiments, we evaluate the effect of Compound Nylestriol Tablet (CNT) on bone mineral density (BMD) in women with postmenopausal osteoporosis. Compound Nylestriol Tablet, which contains 0.5 mg of nylestriol (cyclopentylethinyl estriol) and 0.15 mg of levonorgestrel per tablet, was authorized as a new anti-osteoporotic agent for clinical trial in postmenopausal osteoporosis. Methods. One year's clinical observation was performed in 191 eligible patients who were randomly divided into two groups (A and B). In group A, 119 patients were treated for one year with CNT (one tablet per week) and in group B, 72 patients with placebo. Bone mineral density of lumbar antero-posterior spine (L1-L4), lateral spine, total hip and total forearm positions including radius+ulna at the ultra distal areas, mid areas, and one-third areas, were measured before and after treatment. Biochemical parameters and effects of CNT on uterus, and breast were observed. Results. We found that patients treated with CNT had a significant decrease of bone loss in total forearm, including radius+ulna at the ultra distal, mid, and 1/3 areas compared with control subjects (all P <0.05). An improved BMD tendency could be seen at the lumbar spine. There were no differences in the observed biochemical variables. No side-effects on uterus, or mammary glands were observed. None of the patients had uterine bleeding or vertebral fractures during one year's CNT treatment. Conclusion. These data suggested that CNT is effective, safe and convenient in treating postmenopausal osteoporosis. [ABSTRACT FROM AUTHOR]

Abstract: Background: Adiponectin and leptin, as the main circulating peptides secreted by adipose tissue, are potential contributors to bone metabolism. However, their association with bone mineral density (BMD) is unknown. We investigated whether these serum adipocytokines concentrations are associated with BMD and bone turnover markers. Methods: Serum adiponectin, leptin concentrations, bone turnover biochemical markers, and BMD were determined in 265 premenopausal and 336 postmenopausal Chinese women. Results: In postmenopausal Chinese women, the multiple linear stepwise regression analysis showed that year since menopause, lean mass, estradiol, and adiponectin, but not fat mass, leptin, were independent predictors of BMD in postmenopausal Chinese women. However, in premenopausal Chinese women, adiponectin was not the predictor of BMD. The significant positive correlations between adiponectin and bone-specific alkaline phosphatase (BAP), bone cross-linked N-telopeptides of type I collagen (NTX) were found only in postmenopausal women. Serum BAP, and NTX, but not adiponectin, decreased in response to alendronate therapy. Conclusions: Adiponectin was an independent predictor of BMD, and positively correlated with bone turnover biochemical markers in postmenopausal Chinese women, but not premenopausal women. It suggested that adiponectin may exert a negative effect on bone mass by promoting excessive bone resorption associated with bone loss. However, these effects may be mediated by menopausal status. [Copyright &y& Elsevier]

Abstract: Background: Follicle-stimulating hormone (FSH) and luteinizing hormone (LH) may play an important role in bone mass regulation in postmenopausal women. Methods: A cross-sectional study of 699 healthy Chinese women, aged 20 to 82 y, was conducted. Serum FSH and LH and BMD were measured at the posteroanterior (PA) spine, lateral spine, total hip, and distal forearm. Results: The geometric mean values (±SD) of serum FSH and LH in premenopausal women were 3.94±2.08 and 7.51±2.58 IU/l, respectively, and in postmenopausal women were 28.8±1.88 and 25.6±1.95 IU/l, respectively. The correlation of FSH to BMD at different skeletal regions (r =−0.597–−0.492, P =0.000) was higher than that of LH to BMD (r =−0.452–−0.332, P =0.000). The prevalences of osteoporosis for the quartiles of FSH at various skeletal sites were 0.57%, 0.43%, 27.1%, and 30.9%, respectively; and of LH were 2.14%, 4.43%, 19.5%, and 26.0%, respectively. The prevalence of osteoporosis in 3rd and 4th quartile was more significantly increased than the 1st and 2nd quartile. Conclusions: These data suggest that FSH and LH levels in circulation are associated with BMD changes and osteoporosis occurrence in Chinese women. [Copyright &y& Elsevier]

Abstract: Background: Serum leptin concentration is associated with age, fat and bone mineral density (BMD), and there are ethnic differences in physique and BMD values. The relationship between serum leptin concentration and BMD in Chinese women is presently unknown. We examined the relationship of serum leptin concentration with age, body weight, BMI and BMD in mainland Chinese women. Methods: Serum leptin concentration in a population of 676 Chinese females, aged 20–80 years (45.4±14.8 years, mean±S.D.), was measured using an enzyme-linked immunosorbent assay (ELISA). BMD values were measured by dual-energy X-ray absorptiometry (DXA) at a number of sites: the posteroanterior lumbar spine (PA, L1–L4), lateral lumbar spine (Lat, L2–L4), hip (including the femoral neck (FN) and total hip (T-hip)), and forearm (one-third region (RU1/3) and total region (RUT)). The relationship between changes in serum leptin concentration with age, body weight, height, body mass index (BMI) and BMD values at six sites were analyzed using 10 different regression models, and the models giving the best fit were selected. Results: The cubic regression model best described the changes in serum leptin concentration with age (R2=0.048, p<0.001) and body weight (R2=0.352, p<0.001), while the quadratic regression model was best for serum leptin concentration changes with BMI (R2=0.410, p<0.001); serum leptin concentration was not correlated with height. Serum leptin concentration was significantly higher in postmenopausal than premenopausal women (p<0.001). Serum leptin concentration was correlated with Lat BMD (R2=0.012, p<0.018), FN BMD (R2=0.006, p<0.041) and T-hip BMD (R2=0.013, p<0.004) in the whole population. In premenopausal women, leptin was positively associated with BMD except for Lat (R2=0.029–0.055, p<0.008); in postmenopausal women, leptin was also positively associated with AP, FN, T-hip BMD (R2=0.026–0.042, p<0.007). However, after adjusting for BMI not for body weight, there was no association between serum leptin concentration and age. Meanwhile, after adjustment for age, body weight and BMI, there was no association between serum leptin concentration and BMD values in premenopausal and postmenopausal women. Conclusions: Age-related changes in serum leptin concentration is dependent on BMI, but not a direct determinant of BMD in Chinese females. [Copyright &y& Elsevier]