Objective The aim of this study was to explore the molecular mechanisms involved in aerobic exercise ameliorating insulin resistance (IR) by identifying the differentially expressed proteins in skeletal muscle of mice after 6 weeks aerobic exercise with proteome analysis.Methods Eighty male C57BL/6 mice were randomly divided into normal feed group and IR model group, fed by normal feed and high-fat-diet respectively for 10 weeks.After 10 weeks, the mice from IR model group were confirmed IR.Then IR model group were randomly divided into high-fat-diet control group (HC) and high-fat-diet exercise group (HE).HE group was required to mn on a treadmill for 6 weeks with the intensity of 75％VO2 max.After completion of 6 weeks exercise, fasting serum insulin level (FIN)and oral glucose tolerance test (OGTT) were used to assess the effect of 6 weeks aerobic exercise.Total proteins extracted from quadriceps femoris were separated by two-dimensional gel electrophoresis (2-DE) and the differentially expressed proteins were analyzed using ImageMaster 2D Platinum V5.0, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) and Tandem Mass Spectrometry (LC/LC-MS/MS).Results After 6 weeks aerobic exercise, the FIN of HE group mice decreased significantly compared with HC group; the time point of OGTT peak shifted forward, the peak value of OGTT curve decreased significantly, and the platform stage eliminated.43 protein spots were found altered in HE group compared with HC group using proteome analysis, 21 of which were high abundant proteins.A protein was considered to be significantly differentially expressed (over-expressed or under-expressed) ifthe ratio of intensity between two groups was higher than 1.5-fold.After 6 weeks aerobic exercise, 8 proteins were up- and 14 were down-regulated.Two proteins involved in lipid metabolism were Adipocyte Fatty Acid Binding Protein (AFABP) and Apolipoprotein A-Ⅰ (ApoA-Ⅰ).As compared with HC group, AFABP decreased 50％, while ApoA-Ⅰin HE group increased 2.62 times.Voltage-dependent Anion Channel 1 and 2 (VDAC1.VDAC2) ,which involved in skeletal muscle energy metabolism, decreased 58％ and 42％ respectively.Conclusion 6 week aerobic exercise could improve lipid metabolism in IR mice.4 differentially expressed proteins (AFABP, ApoA-Ⅰ, VDAC1 and VDAC2) were identified as involved in the process of aerobic exercise ameliorating IR with proteome analysis.%目的:采用蛋白组学技术研究6周有氧跑台运动对胰岛素抵抗(Insulin Resistance,IR)小鼠骨骼肌总体蛋白表达的影响,对比筛选差异表达蛋白,分析有氧运动改善小鼠IR的分子机理.方法:选用C57BL/6雄性小鼠80只,将其随机分为正常饮食组(NC,n=20)和IR模型组(n=60),分别饲以基础和高脂饲料10周.鉴定高脂膳食组IR小鼠模型建立成功后,将40只成模的IR小鼠分为高脂饮食安静组(HC,n=20)和高脂饮食运动组(HE,n=20).HE组进行6周、强度为75%VOmax 跑台运动.6周后检测各组小鼠空腹血清胰岛素水平(FIN)及口服葡萄糖耐量实验(OGTT);提取小鼠股四头肌总蛋白进行蛋白质双向电泳(2-DE),采用ImageMaster 2D Platinum V5.0软件分析2.DE电泳图谱,并采用基质辅助激光解吸附离子化飞行时间质谱(MALDI-TOF-MS)和高效液相色谱一串联谱法(LC-MS/MS)分析统计蛋白表达差异.结果:6周有氧跑台运动后,HE组小鼠血清FIN水平显著降低,OGTT曲线峰值出现时间点前移,且峰值下降,平台期消失.比较HC组与HE组小鼠骨骼肌蛋白表达图谱,以蛋白表达量变化大于1.5倍为显著性判定标准,共筛选出43个差异表达蛋白.排除21个为高丰度蛋白后,表达上调蛋白8个、下调蛋白14个.其中与脂代谢相关的蛋白包括脂肪细胞型脂肪酸结合蛋白(AdipocyteFatty Acid Binding Protein,AFABP)和载脂蛋白A-I(Apolipoprotein A-I,ApoA-I).有氧运动引起IR小鼠骨骼肌AFABP表达下降50%、ApoA-I表达上调2.62倍.与HC组相比,与骨骼肌能量代谢相关的蛋白电压依赖性阴离子通道1和2(Voltage-dependentAnion Channel,VDAC)表达分别下降58%和42%.结论:6周有氧运动能够显著改善IR小鼠症状,同时HE组小鼠骨骼肌脂代谢相关蛋白AFABP、ApoA-I和电压依赖性阴离子通道蛋白VDAC1、VDAC2表达受到显著影响.
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