持续光照对大鼠有氧运动后骨骼肌质量及运动耐力的影响  

Effects of Constant Light on Skeletal Muscle Mass and Exercise Endurance after Aerobic Exercise in Rats

作　　者：程凤佳 高扬[1] 杨婷婷 苏香楠 孔祥浩 王圣凯 高久翔 于亮[1] CHENG Fengjia;GAO Yang;YANG Tingting;SU Xiangnan;KONG Xianghao;WANG Shengkai;GAO Jiuxiang;YU Liang(Beijing Sport University,Beijing 100084,China)

机构地区：[1]北京体育大学,北京100084

出　　处：《中国体育科技》2023年第11期91-96,F0003,共7页China Sport Science and Technology

基　　金：中央高校基本科研业务费专项基金资助项目(2022YB019);国家自然科学基金项目(32071168)。

摘　　要：目的:探讨持续光照对大鼠12周有氧运动后骨骼肌质量及运动耐力的影响。方法:32只健康雄性SD大鼠随机分为4组:空白对照(Control)组、有氧运动(Exercise)组、有氧运动+持续光照1周(Exe+LL-1)组和有氧运动+持续光照2周(Exe+LL-2)组。Control组在正常条件下自然饲养12周,Exercise组、Exe+LL-1组和Exe+LL-2组在正常条件下进行12周跑台运动,运动强度为60%-70%VO_(2max),60 min/天,5天/周。停止运动后,Exe+LL-1组和Exe+LL-2组分别给予持续光照1、2周。干预后,测试各组大鼠四肢抓力、耐力,取材并分离双侧腓肠肌,称量湿重并记录;于透射电镜观察肌纤维及线粒体结构形态;麦胚凝集素染色检测骨骼肌肌纤维横截面积;采用微量法检测柠檬酸合酶(citrate synthase,CS)酶活性;Western Blot检测时钟基因Bmal1及过氧化物酶体增殖物激活受体γ辅激活因子1α(peroxisome proliferator activated receptor γ coactivator-1α,PGC-1α)的蛋白表达情况。结果:1)与Control组相比,12周有氧运动使Exercise组耐力跑时间、肌纤维横截面积、CS酶活性、BMAL1及PGC-1α蛋白表达量显著增加(P<0.01)。2)与Exercise组相比,持续光照1周使Exe+LL-1组耐力跑时间(P<0.01)、CS酶活性(P<0.05)、BMAL1(P<0.01)及PGC-1α(P<0.05)蛋白表达量显著下降。3)与Exercise组相比,持续光照2周使Exe+LL-2组耐力跑时间(P<0.01)、肌纤维横截面积(P<0.05)、CS酶活性(P<0.01)、BMAL1(P<0.01)及PGC-1α(P<0.01)蛋白表达量显著下降。4)12周有氧运动后,大鼠骨骼肌线粒体形态规则且均匀分布在Z线两侧;持续光照1周后,线粒体出现大小不一及分布不均的情况;持续光照2周后,肌纤维排列严重紊乱,大部分线粒体内部出现空泡。结论:持续光照可能通过降低BMAL1蛋白表达,抑制PGC-1α蛋白表达,减少有氧运动后骨骼肌线粒体含量,导致运动耐力受损;持续光照可能首先累及运动耐力,随后进一步降低骨骼肌质量。Objectives:To investigate the effects of constant light exposure on skeletal muscle mass and exercise endurance after 12 weeks of aerobic exercise in rats.Methods:Thirty-two healthy male SD rats were randomly divided into four groups:Control group,Exercise group,Exercise+12∶12 h Light-Light cycle for one week(Exe+LL-1)group,and Exercise+12∶12 h Light-Light cycle for two weeks(Exe+LL-2)group.The Control group was reared naturally for 12 weeks under normal conditions.Exercise group,Exe+LL-1 group and Exe+LL-2 group were subjected to running-table exercise for 12 weeks under normal conditions,with exercise intensity 60%-70% VO_(2max),60 min/d,5 d/w.Exe+LL-1 group and Exe+LL-2 group were given constant light(12∶12 h Light-Light)for 1 and 2 weeks after exercise,respectively.After the intervention,the grip strength and endurance of rats in each group were tested,bilateral gastrocnemius muscles were collected and separated,and the wet weight was weighed and recorded;the structural morphology of myofibrils and mitochondria was observed under transmission electron microscope;the cross-sectional area of myofibrils of skeletal muscle was detected by wheatgerm agglutinin staining;the enzyme activity of citrate synthase(CS)was detected by microtitration assay;and the clock gene Bmal1 and peroxisome proliferator-activated receptorγ-coactivated factor 1α(PGC-1α)protein expression.Results:1)Compared with the Control group,12 weeks of aerobic exercise resulted in a significant increase in endurance running time,muscle fiber cross-sectional area,CS enzyme activity,and BMAL1 and PGC-1αprotein expression in the Exercise group of rats(P<0.01).2)Compared with the Exercise group,1 week of constant light resulted in a significant decrease in endurance running time(P<0.01),CS enzyme activity(P<0.05),BMAL1(P<0.01)and PGC-1α(P<0.05)protein expression in the Exe+LL-1 group.3)Compared with the Exercise group,2 weeks of constant light exposure resulted in a significant decrease in endurance running time(P<0.01),muscle fiber cross-s

关 键 词：持续光照 有氧运动 骨骼肌 线粒体生物合成 Bmal1基因 

分 类 号：G804.2[文化科学—运动人体科学]