有氧运动和饮食干预对胰岛素抵抗小鼠骨骼肌脂联素-腺苷酸活化蛋白激酶信号系统的影响研究

The Effect of Aerobic Exercise and Diet on the Adiponectin-AMPK Signaling Pathway in Skeletal Muscle of Mice with Insulin Resistant

目的:探讨有氧运动和饮食干预对胰岛素抵抗(IR)小鼠骨骼肌球形脂联素(G-Adiponectin)及腺苷酸活化蛋白激酶(AMPK)的影响,为运动和饮食辅助防治IR的研究提供理论依据。方法:选用雄性C57BL/6小鼠30只,随机分为正常饮食和IR模型组,后者喂养8周高脂饲料后建立胰岛素抵抗(IR)模型,再将IR模型组分为高脂饮食安静组(HC)、高脂饮食运动组(HE)、正常饮食安静组(HNC)和正常饮食运动组(HNE)。运动组进行6周跑台训练,高脂饮食组继续6周的高脂饮食。实验8周后,采用ELISA法检测小鼠血清空腹胰岛素水平及以口服糖耐量试验(OGTT)检测葡萄糖耐量。14周后,采用NorthernBlot检测腓肠肌AMPKmRNA表达,WesternBlot和免疫荧光染色检测腓肠肌G-Adiponectin、AMPK和pAMPK-Thr172蛋白表达。采用酶法测定小鼠血清甘油三酯(TG)和胆固醇(TC)含量。结果:HE和HNE组骨骼肌细胞AMPKmRNA和蛋白以及pAMPK-Thr172蛋白分别较HC及HNC组表达显著增高;HNE组G-Adiponectin显著高于HNC组;HNC组AMPK蛋白和mRNA表达均显著高于HC组;各组免疫荧光检测结果与WesternBlot结果一致。结论:有氧运动和饮食干预均能有效增强Adiponectin-AMPK信号通路,改善机体的脂质代谢紊乱,从而产生防治IR的效果。

Objective To provide the beneficial effects of exercise and diet on the adiponectin-AMPK signaling pathway under the condition of insulin resistance（IR）,the expression of adiponectin and AMPK in skeletal muscle of mice with insulin resistance after 6 weeks of aerobic exercise and/or diet control was studied. Methods Thirty male C57BL/6 mice were randomly divided into control group and IR group by feeding with normal chow and high fat diet respectively. The mice in IR group were fed with high fat diet for 8 weeks and insulin resistance in the mice was con- firmed. The IR group were randomly divided into high fat diet control group（HC）,high fat diet exercise group（HE）, normal chow control group（HNC）,and normal chow exercise group（HNE）; both NE and HNE groups were undergo- ing treadmill exercise at the intensity of 75% VO2max,1 hour/day,5 days/week for 6 weeks. After 6 weeks,mice were sacrificed and gastrocnemius was removed for mRNA and protein analysis. Serum insulin concentration was evaluated by ELISA. Northern and Western blot were applied to detect AMPK mRNA,globular adiponectin（G-Adiponectin）, AMPK and pAMPK-Thr172 expression. Frozen sections of skeletal muscle stained with immunofluorescence （IF）were evaluated by confocal microscopy. Serum TG and TC were evaluated by CHOD-PAP. Results skeletal muscle AMPK mRNA,protein and pAMPK-Thr172 expression were significantly higher in groups HE and HNE comparing to their untrained control groups. Skeletal muscle G-adiponectin expression in skeletal muscle significantly increased in group HNE comparing to group HNC. Skeletal muscle AMPK mRNA and protein significantly increased in group HNC comparing to group HC. Conclusion Aerobic exercise and diet intervention activated adiponectin-AMPK signaling pathway in mice with insulin resistance.