摘要
目的:观察跑台运动对高脂饮食诱导的肥胖大鼠腓肠肌结构重塑及肌肉生长抑制素(myostatin,MSTN)表达的影响。方法:5周龄健康雄性SD大鼠随机分成对照组和高脂喂养组,分别进行普通饲料和高脂饲料喂养,12周后筛选肥胖大鼠16只,随机分为高脂安静组和高脂运动组。跑台训练持续8周,每周5次,每次60分钟,跑速26米/分钟。测定大鼠腓肠肌重量,HE染色观察腓肠肌纤维横截面积,免疫组化方法测定慢肌肌球蛋白重链(myosin heavy chain,MHC)含量。分别采用realtime PCR技术和western blot方法测定腓肠肌MSTN mRNA和蛋白表达。结果:与对照组相比,高脂饮食喂养大鼠体重和体脂显著增加(P<0.01),TG、TC和LDL水平显著升高,HDL水平显著降低(P<0.05)。持续8周跑台运动显著降低大鼠体重和体脂(P<0.01),改善血脂。与对照组相比,肥胖大鼠腓肠肌重量减轻(P<0.05),肌纤维横截面积减小,慢肌MHC显著增多。与单纯高脂组相比,高脂运动组大鼠腓肠肌/胫骨长明显恢复(P<0.01),肌纤维横截面积显著增加,未发现慢肌MHC染色。此外,肥胖大鼠腓肠肌MSTN mRNA和蛋白表达显著增加(P<0.01)。与单纯高脂组相比,高脂运动组大鼠腓肠肌MSTN mRNA和蛋白表达水平显著降低(P<0.01)。结论:8周跑台运动明显逆转了高脂饮食诱导的肥胖大鼠腓肠肌结构重塑,其机制可能与MSTN的表达调节相关。
Objective To observe the effect of treadmill running on the muscle structure remodeling and the myostatin（MSTN）expression in gastrocnemius of obese rats induced by high-fat diet.Methods5-week-old male SD rats were randomly divided into control group,high-fat diet induced obese sedentary group,and high-fat diet induced obese exercise group.The rats in exercise group underwent treadmill running 60min per day,5 days per week at the speed of 26 m/min for 8 weeks.Gastrocnemius weight,cross section area of gastrocnemius muscle fiber,slow myosin heavy chain（MHC）,and the mRNA and protein expression of MSTN were observed.Results Comparing with control group,body weight,body fat,TG,TC and LDL increased（P 〈 0.01）,muscle weight,cross section area and slow MHC muscle fiber type and HDL decreased（P 〈 0.05）in obese groups.Body weight,fat,and mRNA and protein levels of MSTN in gastrocnemius muscle of obese exercise group reduced significantly（P 〈 0.01）.Conclusion The results showed that exercise improved remodeling of gastrocnemius muscle structure and reversed the upregulation of MSTN in gastrocnemius muscle induced by high fat diet.
出处
《中国运动医学杂志》
CAS
CSCD
北大核心
2014年第5期446-452,共7页
Chinese Journal of Sports Medicine
基金
国家自然科学基金(81270921)
教育部人文社会科学研究青年基金(10YJC880156)
