运动降低MG53表达及其在缓解高脂膳食大鼠IR中的作用  

The Effect of Exercise on MG53 in Rat with Insulin Resistance

作　　者：齐洁[1] 任彩玲[2] 傅建[3] 张钧[1] 

机构地区：[1]上海师范大学体育学院,上海200234 [2]赣南医学院康复学院,江西赣州341000 [3]扬州大学体育学院,江苏扬州225009

出　　处：《中国运动医学杂志》2016年第3期240-247,共8页Chinese Journal of Sports Medicine

基　　金：国家自然科学基金(31571223);上海师范大学理工科一般科研项目(SK201514)

摘　　要：目的:观察游泳运动对高脂诱导的胰岛素抵抗(IR)大鼠骨骼肌脂质沉积相关基因及MG53的影响,探讨MG53-IRS1通路在胰岛素抵抗发生中的作用,为运动防治胰岛素抵抗提供理论依据。方法:以SD大鼠为实验对象,随机分为3组:普通饮食对照组(C组)、高脂饮食IR模型组(H组)、高脂饮食90min运动组(HE组)。通过8周高脂饲料喂养建立IR大鼠动物模型,同时对HE组大鼠实施每天2次45min无负重游泳运动干预。运用正糖钳技术结合HOMA-IR、ISI综合评价动物模型的建立;通过观察运动对高脂饮食大鼠骨骼肌甘油三酯(TG)含量,骨骼肌PPARγ的辅激活子-1(PGC-1α)、脂肪酸转位酶FAT/CD36、MG53和胰岛素受体底物-1(IRS-1)m RNA的表达量及p IRS-1Ser307、IRS-1蛋白表达水平的变化,探讨运动干预IR的机制。结果:(1)IR动物模型评价:8周高脂饮食喂养后,与C组相比,H组大鼠葡萄糖输注速率(GIR)显著下降(P<0.01),ISI水平显著下降(P<0.01),HOMA-IR水平显著增加(P<0.01),提示胰岛素抵抗大鼠建模成功。(2)运动对IR的影响:8周游泳干预后,与H组相比,HE组大鼠GIR显著增加(P<0.01),血清胰岛素含量和HOMA-IR水平均显著降低(P<0.01),ISI水平显著增加(P<0.01);HE组大鼠骨骼肌TG含量显著下降(P<0.05),PGC-1-α和FAT/CD36 m RNA表达量均显著降低(P<0.01),骨骼肌MG53 m RNA和蛋白表达水平均显著下降(P<0.05,P<0.01),骨骼肌IRS-1 m RNA表达量水平显著增加(P<0.01),p IRS-1Ser307表达水平显著下降(P<0.01),IRS-1蛋白表达水平显著增加(P<0.05)。结论:8周游泳运动可以通过减少骨骼肌脂质沉积,降低大鼠骨骼肌MG53表达水平,增加IRS-1的表达,从而可能通过增强胰岛素信号转导,延缓高脂饮食大鼠IR的发生。Objective To study the effect of exercise on the lipid deposition related genes（PGC-1α,FAT/CD36）and mitsugumin 53（MG53）in rats with high-fat diet induced insulin resistance. Methods 29 SD rats were randomly assigned to（1）sedentary normal diet group（C,n=10）,（2）sedentary high-fat diet group（H,n=9）,（3）high-fat diet plus exercise group（HE,n=10）. Rats in group HE performed 45-min swimming twice a day with an interval of 8 hours,6 days per week,for a total of 8 weeks. Thereafter,the body weight,FBG,FINS,HOMA-IR,ISI,TG,PGC-1α,FAT/CD36,MG53 and IRS-1 were determined to evaluate the outcome of high-fat diet and exercise intervention. Results After the experiment,（1）in group H,the levels of insulin and HOMA-IR increased dramatically（P〈0.01）,the glucose infusion rate（GIR）decreased significantly（P〈0.01）,the level of ISI decreased markedly（P〈0.01）as compared with the group C,（2）in group HE,the GIR increased significantly（P〈0.01）,the level of INS and HOMA-IR decreased dramatically（P〈0.01）,the level of ISI increased obviously（P〈0.01） the content of TG decreased significantly（P〈0.05）,the m RNA expression of PGC-1α and FAT/CD36 increased obviously（P〈0.01）,the m RNA and protein expression of MG53 decreased markedly（P〈0.01）,the m RNA and protein expression of IRS-1 increased dramatically（P〈0.01,P〈0.05）,the protein expression of p IRS-1Ser307 decreased obviously（P〈0.01）as compared with the group H. Conclusion Swimming exercise can ameliorate high-fat-diet induced insulin resistance in rats through reducing the expression of lipid deposition related genes,decreasing the m RNA and protein expression of MG53,and enhancing the insulin signaling transduction.

关 键 词：胰岛素抵抗 MG53 胰岛素受体底物1 运动 

分 类 号：R87[医药卫生—运动医学]