有氧运动训练对大鼠心肌缺血/再灌注损伤致心肌细胞凋亡的作用

Effects of aerobic exercise training on myocardial apoptosis induced by ischemia-reperfusion injury

目的应用大鼠在体心脏缺血/再灌注损伤(ischemia/reperfusion injury,I/RI)动物模型,观察缺血/再灌注(I/R)后运动训练(exercise training)对心肌细胞凋亡的作用以及与磷脂酸肌醇3激酶蛋白激酶B(PI3K/Akt)信号通路可能存在的相互作用,探讨运动训练对心脏保护作用的可能机制。方法 60只SD大鼠建模后随机分成3组:假手术组,I/R组,I/RI+运动训练组。LTTC染色检测心肌梗死范围;采用TUNEL荧光标记法检测心肌凋亡;Caspase-3试剂盒检测caspase-3活性;免疫印迹法检测p-Akt水平。结果与I/R组比较,运动训练可以减少心肌梗死范围(n=9,P<0.01),可以明显抑制心肌细胞凋亡(n=10,P<0.01),降低caspase-3活性(n=8,P<0.01),有效提高I/R后心肌p-Akt水平(n=7,P<0.01)。结论运动训练对I/RI的心肌具有保护作用,其可能是通过PI3K/Akt信号通路实现的。

AIM To investigate the effects of aerobic exercise training on myocardium undergoing ischemia and reperfusion injury （I/RI）. METHODS Sixty male healthy Sprague Dawley rats were randomized into three groups： A, sham operation group; B, I/RI group, ischemia 30 rain, reperfusion 4 h, and C, I/RI ＋ aerobic exercise training group. Myocardial infarct size, apoptotic index of eardiomyocytes, caspase-3 activity and p-Akt levels were detected. RESULTS Aerobic exercise training reduced myocardial infarct size （ n = 9, P 〈 0. 01 ）, inhibited cardiomyocyte apoptosis （ n = 10, P 〈 0. 01 ）, decreased caspase-3 activity （ n = 8, P 〈 0. 01 ）, and significantly increased p-Akt levels （ n = 7, P 〈 0. 01 ）. CONCLUSION Aerobic exercise training plays a protective role on myoeardium undergoing ischemia and reperfusion iniury, and its protective effect is partially through PI3K/Akt signal Dathwav.