抗阻训练对衰老小鼠心肌Sarcopenia中Akt/mTOR信号通路的影响

Effect of Resistance Training on Akt/mTOR Signaling Pathway of Aging Mice Cardiac Sarcopenia

目的:探讨抗阻训练对衰老小鼠心肌sarcopenia中Akt/mTOR信号通路的影响。方法:雄性,3月龄SAMP8小鼠随机分为对照组(n=12)和抗阻训练组(n=12)。对照组常规喂养至6月龄,达到衰老后处死;抗阻训练组进行3个月的抗阻训练,建立衰老小鼠抗阻训练运动模型,使用实时荧光定量PCR技术,对小鼠心肌Akt/mTOR信号通路中Akt、mTOR、p70S6K和eIF-4E基因mRNA的表达进行测定。结果:衰老小鼠出现心肌纤维数目减少,心肌纤维空白区域面积增多;抗阻训练后,小鼠心脏重量和心系数与衰老对照组相比虽然显著增加(P<0.05)但没有产生病理性心肌肥大;心肌纤维空白区域面积小于对照组;抗阻训练组Akt、mTOR、p70S6K和eIF-4E基因mRNA的表达与衰老对照组相比显著上升(P<0.05)。结论:抗阻训练可以增强衰老小鼠心肌Akt/mTOR信号通路中各基因mRNA的表达,产生运动性心肌肥大,并对心肌产生保护性调节作用,改善衰老小鼠的心脏功能。

Objective： To study the effect of resistance training on cardiac sarcopenia. Methods： Male SAMP8 3-months old mice were randomly divided into control group （n= 12 ） and resistance training group （n= 12）. The control group was executed at 6-months old. After inducing the animal model of resistance training, using the real-time PCR system to analyze the mRNA expression of Akt, mTOR, p70S6K and elF-4E in mouse heart. Result： The aging mice turned cardiac sarcopenia. After resistance training, the mouse heart weight and the ventricular mess index significantly increased （P〈0.05）, without pathological cardiac hypertrophy, and did not turn cardiac sareopenia. The mRNA expressions of Akt, mTOR, p70S6K and elF-4E of resistance training group increased significantly than that of the aging control group （P〈0.05）. Conclusion： The resistance training can elevate the cardiac P13-K/Akt signaling pathway expression, induce exercise cardiac hypertrophy, start the cardiac cell protection control action, and improve the cardiac function of aging mice.