Filip Rafal, Raszewski Grzegorz
Department of Bone Metabolic Diseases, and Department of Internal and Occupational Diseases, Institute of Agricultural Medicine, Lublin, Poland.
Clin Endocrinol (Oxf). 2009 Feb;70(2):214-20. doi: 10.1111/j.1365-2265.2008.03313.x. Epub 2008 Jun 10.
Recent studies have shown that parallel changes in body weight and bone mass can be partially mediated via circulating leptin. Therefore, among the hormones involved in bone and mineral metabolism, such as oestrogens, testosterone and parathormone, leptin has recently become a subject of considerable interest. The aim of this study was to assess associations between leptin, E(2), testosterone, dehydroepiandrosterone sulphate (DHEA-S), SHBG, alpha-ketoglutaric acid (AKG) and bone mineral density (BMD) and bone turnover markers in overweight and obese postmenopausal women.
Eighty healthy, postmenopausal Caucasian women were studied. BMD of the lumbar spine (L(2)-L(4)) and femoral neck regions were examined using the dual X-ray absorptiometry (DXA) method. Associations were evaluated in stepwise multiple regression analysis, including information on the possible confounders and effect modifiers, for example, age, years since menopause, height and weight.
Femoral neck BMD was positively correlated with weight (r = 0.52, P < 0.000001), body mass index (BMI) (r = 0.48, P < 0.000006), hipline (r = 0.48, P < 0.00006), waistline (r = 0.45, P < 0.00002) and DHEA-S (r = 0.36, P < 0.0008). Correlations of E(2), SHBG, testosterone and leptin, as well as biochemical markers of bone turnover with L(2)-L(4) and femoral neck BMD were not found. In the whole study group, significant predictors of L(2)-L(4 )BMD were BMI (beta = 0.35, P < 0.01) testosterone (beta = 0.27, P < 0.05) and osteocalcin (OC) (beta = 0.22, P < 0.05) (R(2) = 0.23), while predictors of femoral neck BMD were BMI (beta = 0.42, P < 0.001), testosterone (beta = 0.24, P < 0.05), E(2) (beta = 0.19, P < 0.05), as well as osteocalcin (beta = 0.20, P < 0.05) (R(2) = 0.41). In the subgroup with BMI 30-39.9, the significant predictors of both L(2)-L(4 )and femoral neck BMD were testosterone (beta = 0.32, P < 0.05, R(2) = 0.19; beta = 0.33, P < 0.05, R(2) = 0.29) and osteocalcin (beta = 0.34, P < 0.05, R(2) = 0.19; beta = 0.45, P < 0.01, R(2) = 0.29). In the subgroup with waist : hip ratio (WHR > or = 0.85, the predictor of L(2)-L(4 )BMD was E(2) (beta = 0.38, P < 0.05) (R(2) = 0.21), whereas the predictors of femoral neck BMD were BMI (beta = 0.29, P < 0.05) and testosterone (beta = 0.35, P < 0.01) (R(2) = 0.36).
The main endocrine variable predicting lumbar spine BMD in overweight and obese postmenopausal females was testosterone, while the main determinants of femoral neck BMD were both testosterone and E(2). No effect was found of serum leptin on examined indicators of bone status.
近期研究表明，体重和骨量的平行变化可部分通过循环中的瘦素介导。因此，在参与骨与矿物质代谢的激素中，如雌激素、睾酮和甲状旁腺激素，瘦素最近成为了一个备受关注的课题。本研究的目的是评估超重和肥胖绝经后女性中瘦素、雌二醇（E₂）、睾酮、硫酸脱氢表雄酮（DHEA-S）、性激素结合球蛋白（SHBG）、α-酮戊二酸（AKG）与骨密度（BMD）及骨转换标志物之间的关联。
对80名健康的绝经后白人女性进行了研究。使用双能X线吸收法（DXA）检测腰椎（L₂-L₄）和股骨颈区域的骨密度。在逐步多元回归分析中评估关联，包括有关可能的混杂因素和效应修饰因素的信息，例如年龄、绝经年限、身高和体重。
股骨颈骨密度与体重（r = 0.52，P < 0.000001）、体重指数（BMI）（r = 0.48，P < 0.000006）、臀围（r = 0.48，P < 0.00006）、腰围（r = 0.45，P < 0.00002）和DHEA-S（r = 0.36，P < 0.0008）呈正相关。未发现E₂、SHBG、睾酮和瘦素以及骨转换生化标志物与L₂-L₄和股骨颈骨密度之间的相关性。在整个研究组中，L₂-L₄骨密度的显著预测因素是BMI（β = 0.35，P < 0.01）、睾酮（β = 0.27，P < 0.05）和骨钙素（OC）（β = 0.22，P < 0.05）（R² = 0.23），而股骨颈骨密度的预测因素是BMI（β = 0.42，P < 0.001）、睾酮（β = 0.24，P < 0.05）、E₂（β = 0.19，P < 0.05）以及骨钙素（β = 0.20，P < 0.05）（R² = 0.41）。在BMI为30 - 39.9的亚组中，L₂-L₄和股骨颈骨密度的显著预测因素均为睾酮（β = 0.32，P < 0.05，R² = 0.19；β = 0.33，P < 0.05，R² = 0.29）和骨钙素（β = 0.34，P < 0.05，R² = 0.19；β = 0.45，P < 0.01，R² = 0.29）。在腰臀比（WHR≥0.85）的亚组中，L₂-L₄骨密度的预测因素是E₂（β = 0.38，P < 0.05）（R² = 0.21），而股骨颈骨密度的预测因素是BMI（β = 0.29，P < 0.05）和睾酮（β = 0.35，P < 0.01）（R² = 0.36）。
超重和肥胖绝经后女性中，预测腰椎骨密度的主要内分泌变量是睾酮，而股骨颈骨密度的主要决定因素是睾酮和E₂。未发现血清瘦素对所检测的骨状态指标有影响。
