不同有氧运动时间对小鼠心肌细胞凋亡的影响

Effects of different aerobic exercise time on myocardial cell apoptosis in mice

目的比较不同有氧运动时间对小鼠心肌细胞凋亡的影响及作用机制。方法 80只2月龄雄性清洁级BALB/c小鼠随机分为短期静止组、长期静止组、短期运动组和长期运动组各20只。短期静止组和短期运动组小鼠饲养和有氧训练3个月,长期静止组和长期运动组小鼠饲养和有氧训练6个月。分别采用TUNE法、RTPCR法和蛋白印迹法测定心肌细胞凋亡情况以及Bcl-2、Bax的mRNA和蛋白表达。结果长期运动组小鼠心肌细胞凋亡指数较其他三组小鼠明显下降(P<0.05),并且心肌Bcl-2 mRNA及蛋白表达水平、Bcl-2/Bax比值较长期静止组及短期静止组小鼠显著上升(P<0.05),而Bax mRNA及蛋白表达水平较长期静止组、短期静止组显著下降(P<0.05)。与短期运动组比较,长期运动组Bcl-2/Bax mRNA比值及蛋白比值得到明显改善(P<0.05)。短期运动组小鼠的心肌细胞凋亡指数以及心肌Bcl-2、Bax表达较短期静止组有所改善,但差异无统计学意义。结论 6个月有氧运动训练可有效阻止小鼠心肌细胞凋亡,改善心肌细胞Bcl-2、Bax表达和Bcl-2/Bax水平是其重要的作用途径。

Objective To compare the effects of different aerobic exercise time on cardiomyocyte apoptosis and its mechanism in rats. Methods 80 male clean grade BALB/c mice were split into short-period quiet group, long-period quiet group, short- period exercise group and long-period exercise group, each of 20 mice. The feeding and aerobic training time of mice in short-term quiet group and short-term exercise group was 3 months, and the time of feeding and aerobic training in long-term quiet group and long- term exercise group was 6 months. The TUNE kit was used to detect the apoptosis of cardiac myocytes, and the mRNA and protein expression of Bcl-2 and Bax mRNA in cardiac myocytes were assessed by RT-PCR and Western blot method. Results The eardiomyocyte apoptosis index of mice in the long-period exercise group was significantly lower than those in the short-perlod aerobic training mice and the long-perlod and short- period quiet group. The levels of Bcl-2 mRNA and protein expression in their myocardium were significantly higher than those in the long-period and short-period quiet group （P 〈 0.05） , and the Bax mRNA and protein expression were significantly lower than those in the long-period and short-period quiet group （P 〈 0.05）. The Bcl-2/Bax mRNA mRNA and protein ratio of the long-term exercise group were significantly improved compared with the short-term group （P 〈 0.05）. The myocardial apoptosis index and the expression of Bcl-2 and Bax in the short-period exercise group were improved compared with those in the short-period quiet group, but the difference was not obvious Conclusion 6 months of aerobic exercise can effectively prevent cardiomyocyte apoptosis in mice. It is an important way to effectively regulate Bcl-2, Bax expression and Bcl-2/Bax level of cardiomyocytes.