运动干预对胰岛素抵抗大鼠骨骼肌蛋白激酶B活性和蛋白与基因表达的影响

关键词：胰岛素抵抗  运动  蛋白激酶B  骨骼肌

Keywords:insulin-resistance  exercises  protein kinase B  skeletal muscle

摘要：

      目的：探讨一次性游泳运动对胰岛素抵抗大鼠骨骼肌蛋白激酶B（protein kinaes, PKB）mRMA表达、蛋白总量（t- PKB）及磷酸化PKB（p-PKB）的影响。方法：SD大鼠随机分为正常饮食组、高脂饮食组、高脂饮食+运动组。分别对高脂饮食组与高脂饮食+运动组饲以高脂饲料，4周后对高脂饮食+运动组大鼠运动干预2h。测血液葡萄糖和胰岛素浓度；Western blot法检测骨骼肌t-PKB蛋白表达、p-PKB磷酸化水平；RT-PCR法分析PKB mRNA表达。结果：高脂饮食组血糖和胰岛素浓度明显高于对照组；高脂饮食+运动组血糖和胰岛素浓度低于高脂饮食组；高脂饮食组PKB mRNA表达下降；高脂饮食+运动组 PKB磷酸化水平和蛋白总量高于高脂饮食组。结论：运动干预改善高脂饮食诱发胰岛素抵抗大鼠对胰岛素的敏感性，增加PKB磷酸化水平和蛋白与基因的表达。

Abstract:

      Objective:To investigate the effects of a single bout of exercises on PKB phosphorylation, protein and gene expression in skeletal muscle of insulin-resistance rats. Method:Male rats were randomly divided into control diet and high-fat diet(HFD) and high-fat diet trained groups. Except control group, the rats were fed high-fat diet for 4 weeks and then the rats in exercises group exercised for 2 h swimming. The serum levels of glucose and insulin were measured. The levels of PKB protein and phosphorylation were determined by Western blot and the level of PKB mRNA was determined by reverse transcription polymerase chain reaction(RT-PCR). Result:Compared with control group, the serum levels of glucose and insulin increased in HFD rats. The serum levels of glucose and insulin in HFD with exercises training rats was significantly lower than that in HFD rats. The level of PKB mRNA in HFD rats was decreased as compared to control. The levels of PKB phosphorylation and protein expresson in HFD with exercises training rats were higher than that in HFD rats. Conclusion:Exercises may improve PKB phosphorylation and protein and gene expression,elevate the sensitivity of skeletal muscle to insulin.