不同强度耐力运动对骨骼肌质量的影响:自噬与衰老  

Effects of Different Intensity Endurance Exercise on Skeletal Muscle Mass: Autophagy and Aging

作　　者：邱守涛[1,2] 崔迪[1,2] 付绍婷 张蕴琨[3] 陈彩珍[1,2] 卢健[1,2] 

机构地区：[1]青少年健康评价与运动干预教育部重点实验室,上海200241 [2]华东师范大学体育与健康学院,上海200241 [3]南京体育学院,江苏南京210014

出　　处：《沈阳体育学院学报》2015年第1期78-84,90,共8页Journal of Shenyang Sport University

基　　金：上海市浦江人才计划(10PJC029);青少年健康评价与运动干预教育部重点实验室建设项目(40500-541235-14203/004)

摘　　要：目的:观察不同强度耐力运动对SAMP6小鼠骨骼肌质量及自噬的影响。方法:3月龄雌性SAMP6小鼠随机分为安静组(P,n=5)及高(PH,n=5)、中(PM,n=5)、低(PL,n=5)强度耐力运动组,SAMR1小鼠为正常对照组(R,n=5);运动组小鼠进行8周跑台耐力运动,速度分别为28、18、8 m/min。结果:1)与R组比,快速老化小鼠体重均显著增加(P<0.05),P、PM、PL组骨骼肌重量显著下降(P<0.05),P组肌纤维横截面积降低(P<0.05),肌细胞间隙增大、形状不规则并出现核居中现象,MHC1及Myo D1 mRNA表达下调(P<0.05),MSTN mRNA含量增加(P<0.05);与P组比,PH组骨骼肌重量及肌纤维横截面积显著增加(P<0.05),PH、PM、PL组MSTN mRNA表达下调(P<0.05)。2)与R组比,P组小鼠骨骼肌P62 mRNA及蛋白表达显著增加(P<0.05);与P组比,PM组LC3Ⅱ/LC3Ⅰ比值显著升高并高于PL组,PH、PM、PL组p62蛋白表达下调(P<0.05)。结论:1)SAMP6小鼠体重增加而骨骼肌重量显著降低提示其发生骨骼肌衰减,耐力运动尤其是高强度耐力运动可有效缓解这一现象;2)衰老进程中,降解机制障碍导致自噬水平降低可能参与骨骼肌衰减的发生,耐力运动尤其是中等强度耐力运动可有效提高自噬水平而缓解骨骼肌衰减。Objective：To study the effects of endurance exercise on autophagy and the muscle mass during aging. Methods： Female SAMP6 mice were divided randomly into sedentary group （ P, n = 5 ）, high- （ PH, n = 5 ）, moderate- （ PM, n = 5 ） and low- （PL,n = 5 ） intensity exercise group. The SAMR1 mice were assigned as the normal control （R,n = 5 ）. The mice of PH, PM and PL undertook 8-week treadmill training, and the speed verified as 28,18 and 8 m/min separately. Results： 1 ） Compared to R, the body weight of SAMP6 mice increased obviously （ P 〈 0.05 ） while the skeletal muscle mass of P, PM and PL dropped （ P 〈 0.05 ） ; the myofiber cross-section area in group P decreased while the gap of myofiber in- creased. The irregular shape of myofiber appeared and the cell nucleus mediated;the MHC1 and MyoD1 mRNA decreased sharply in group P （P 〈 0.05 ） while MSTN mRNA expression up regulated seriously （ P 〈 0.05 ） ; compared to P, the muscle mass and the myofiber cross-section area of PH increased and the MSTN mRNA relative content in PH, PM and PL decreased incredibly. 2） Compared to R,both mRNA and protein content of p62 accelerated in P;compared to P, the ratio of LC3 I//LC3 I increased in PM ,higher than it in PL, and the p62 protein content down regulated in PH, PM and PL. Conclusions ： 1 ） It was implied that sarcopenia occurred in the SAMP6 mice with the body weight increasing and the skele- tal muscle decreasing, and this phenomena can be ameliorated by endurance exercise, especially the high-intensity exercise. 2） In the process of aging,it is the degradation impairment of autophagy that involves in the induction of sarcopenia, and the autophagy regulation induced by endurance exercise, especially the moderate-intensity exercise,plays an important role in the exercise therapeutic of sarcopenia.

关 键 词：耐力运动 骨骼肌质量 衰老 自噬 骨骼肌衰减 

分 类 号：G804.22[文化科学—运动人体科学]