睾酮对衰老心肌细胞及细胞周期调控因子的作用  

Effect of testosterone on aging myocardial cell and the cell cycle regulation

作　　者：邢晓雯[1] 吴赛珠[1] 阮云军[2] 何天民[1] 刘新强[1] 赖文岩[1] 

机构地区：[1]南方医科大学南方医院心内科,广东广州510515 [2]广州军区总医院心内科

出　　处：《中国老年学杂志》2009年第6期641-644,共4页Chinese Journal of Gerontology

基　　金：国家973项目子课题(No.2007CB507400)

摘　　要：目的探讨不同剂量睾酮对心肌细胞衰老的干预作用及其可能机制。方法用1μmol/L、100nmol/L、10nmol/L三种剂量睾酮干预自然衰老的小鼠心肌细胞,应用流式细胞仪检测各组细胞周期分布,用RT-PCR及Western印迹检测各组细胞p16INK4a、cyclinD1mRNA、蛋白及去磷酸化RB蛋白的表达。结果与衰老心肌细胞相比,1μmol/L、100nmol/L、10nmol/L睾酮干预细胞G0/G1期比例明显降低(P<0.05),这一作用具有剂量依赖性。睾酮干预可上调cyclinD1mRNA及蛋白表达,下调p16INK4amRNA及蛋白表达,并使去磷酸化RB蛋白表达下降(P<0.05),而这些作用均可被雄激素受体阻断剂而不被雌激素受体阻断剂所阻断(P<0.05)。结论睾酮可剂量依赖性的抑制小鼠心肌细胞衰老,这一作用部分是通过睾酮上调cyclinD1表达,下调p16INK4a及去磷酸化RB蛋白表达而实现的。Objective To investigate the effect of testosterone on the aging myocardial cell and the possible mechanism. Methods 1 μmol/L, 100 and 10 nmol/L testosterone were administrated on natural aging murine myocardial cells, and the distribution of cell cycle was measured by flow cytometry, p16INK4a, cyclinD1 mRNA and protein and dephosphorylation RB protein were detected by RT-PCR and Western-blot in each group. Results Compared with the aging myocardial cell, 1 μmol/L, 100 and 10 nmol/L testosterone could diminish the ratio of G0/G1 phase in a dose-dependent way （P 〈0. 05）. 1 μmol/L, 100 and 10 nmoL/L testosterone could induce up-regulations of cyclinD1 mRNA and protein, down-regulations of p16INK4a mRNA and protein and dephosphorylation RB protein （ P 〈 0. 05 ）, which could be blocked by flutamide but not ICI182, 780 （P 〈0. 05）. Conclusions 1μmol/L, 100 and 10 nmol/L testosterone can inhibit the senescence of natural aging murine myocardial cell in a dose-dependent way, which results from the up-regulation of cyclinD1, and down-regulations of p16INK4a and dephosphorylation RB.

关 键 词：衰老 睾酮 RB CYCLIND1 P16INK4A 

分 类 号：R329.12[医药卫生—人体解剖和组织胚胎学]