高脂膳食及有氧运动对C57BL/6小鼠骨骼肌基因表达谱的影响

关键词：高脂膳食  有氧运动  胰岛素抵抗  基因芯片

Keywords:high-fat-diet  aerobic exercise  insulin resistance  gene microarray

摘要：

      摘要 目的：运用基因芯片技术研究高脂膳食及有氧运动因素对C57BL/6小鼠骨骼肌基因表达谱的影响，初步探寻有氧运动改善机体胰岛素抵抗（IR）相关基因的机制。 方法：选用C57BL/6雄性小鼠80只，随机分为正常饮食组和IR模型组，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，将正常饮食组随机分为正常饮食安静组 (NC) 和正常饮食运动组 (NE)，IR模型组分为高脂饮食安静组 (HC) 和高脂饮食运动组 (HE)。运动方案采用强度为75% VO2max有氧跑台训练，持续6周。后分离各组小鼠股四头肌，提取总RNA，经荧光标记后进行芯片杂交，利用芯片扫描仪记录荧光信号，并通过相关软件对所得数据进行统计分析。 结果：HC/NC共筛选差异表达基因136个；NE/NC筛选差异表达基因74个；筛选HE/HC差异表达基因29个； HE/NC差异表达基因共252个，其中170个基因 (HE/NC-DF) 的差异表达由高脂膳食和运动因素共同引起；HE/HC中16个基因为与HE/NC-DF共同差异基因。 结论：高脂膳食及有氧运动对小鼠骨骼肌基因表达均有显著影响，本研究初步筛选出有氧运动改善IR潜在相关基因，为进一步研究有氧运动改善IR分子机制提供了理论依据。

Abstract:

      Abstract Objective: To investigate the effects of high-fat-diet and aerobic exercise on global gene expression in skeletal muscle of C57BL/6 mice with gene microarray analysis and explore the relevant genes which are involved in aerobic exercise ameliorating insulin resistance(IR). Method: 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. Then the mice from IR model group were confirmed IR by fasting serum insulin and oral glucose tolerance test(OGTT). The two groups were then further divided into normal feed sedentary control group(NC) and normal feed exercise group(NE), high-fat-diet sedentary control group(HC) and high-fat-diet exercise group(HE) respectively. The mice in exercise groups were subjected to 6 weeks of treadmill training at the intensity of 75% VO2max. Then quadriceps femoris samples were removed and total RNA was extracted from tissues and labeled with two color fluorescent dye for microarray hybridization. The microarray slides were scanned to generate gene lists with corresponding fluorescence intensity data which was analyzed with related software. Result: The results showed that 136 genes were differentially expressed in HC group compared to NC group; 74 genes were shown to exhibit differential expression profiles in NE group compared to NC group; 29 genes were differentially expressed in HE group compared to HC group, while 252 genes were found when compared to NC group; Of the 252 genes, 170 exclusive genes (HE/NC-DF) expression were affected by both high-fat-diet and aerobic exercise factors; 16 of the HE/NC-DF genes were common with the differentially expressed genes in HE group compared to HC group. Conclusion: This study demonstrated that high-fat-diet and aerobic exercise factors subtly regulated the gene expression of skeletal muscle in C57BL/6 mice. Sixteen highly promising gene relevant to aerobic exercise ameliorating IR were identified, and the data provides theoretical evidence for further studies about its molecular mechanisms.