SOCS-3在耐力运动改善膳食性瘦素抵抗中作用机制的研究  

Roles of SOCS-3 in the Effects of High-fat Diet and Endurance Exercise on Skeletal Muscle Leptin Resistance

作　　者：胡建忠[1] 刘海平[2] 

机构地区：[1]衡阳师范学院体育系,湖南衡阳421008 [2]温州医学院体育科学学院,浙江温州3250351

出　　处：《体育科学》2010年第3期53-58,共6页China Sport Science

基　　金：湖南省自然科学基金项目(09JJ6027)

摘　　要：目的:分析SOCS-3与瘦素受体LRb的结合作用,探讨高脂膳食条件下耐力运动对骨骼肌瘦素抵抗的预防或改善机制。方法:32只大鼠随机平均分成普通膳食对照组(CS)、普通膳食运动组(CE)、高脂膳食对照组(HS)、高脂膳食运动组(HE)。CE、HE组进行12周跑台训练,跑速20 m/min。最后一次训练后48 h,测试空腹血糖、血液甘油三酯(TG)、胰岛素、瘦素以及红色(RG)、白色(WG)腓肠肌的甘油三酯。采用Real-time PCR测定RG、WG肌的SOCS-3 mRNA表达水平,采用免疫共沉淀技术测定RG、WG肌SOCS-3蛋白与瘦素受体LRb的结合活性。结果:1)HS组体重增长率最高,HS组体重、血糖、血液甘油三酯、胰岛素、瘦素均显著高于CS组(P<0.05);HE组血液胰岛素、瘦素水平显著低于HS组(P<0.05)。2)RG肌TG含量:HS组显著低于CS组(P<0.05),HE组显著高于HS组(P<0.05)。WG肌TG含量:CE组显著高于CS组(P<0.05),HE组显著高于HS组(P<0.05)。3)RG肌SOCS-3 mRNA表达:CE、HS组显著高于CS组(P<0.01)。WG肌SOCS-3 mRNA表达:CE组显著高于CS组(P<0.01)。4)RG肌SOCS-3蛋白与瘦素受体LRb的结合活性:HS组显著高于CS组(P<0.05),HE显著低于HS组(P<0.05)。结论:1)高脂膳食显著降低红色腓肠肌的TG含量,表明高脂膳食性瘦素抵抗易发于红肌,高脂膳食能降低红肌的脂肪代谢能力;耐力运动对红肌的瘦素抵抗有显著的逆转作用;2)耐力运动和高脂膳食都能上调红色腓肠肌SOCS-3 mRNA表达,SOCS-3 mRNA表达对运动和膳食的应答反应在肌纤维类型之间存在差异,至少白肌耐力运动与高脂膳食还存在负交互作用;3)高脂膳食导致骨骼肌瘦素抵抗,至少有一部分机制使SOCS-3与LRb受体的结合增加。耐力运动对高脂膳食性瘦素抵抗的改善机制,至少有一部分是因为运动解除了SOCS-3与LRb受体的结合,减弱了SOCS-3对瘦素信号的抑制作用。Objective：To investigate the action of SOCS-3 binding to leptin receptor LRb,and discover the mechanism of endurance exercise on high-fat diet induced skeletal muscle leptin resistance.Methods：32 Sprague-Dawley rats were randomly assigned to standard diet control group（CS,n=8）,standard diet endurance group（CE,n=8）,high-fat diet control group（HS,n=8）,high-fat diet endurance group（HE,n=8）.Endurance group rats were accustomed to 12-week treadmill training with a speed of 20m/min.48h after the last treadmill training all rats were sacrificed,the concentrations of blood glucose,triacylglycerol（TG）,leptin and insulin were measured.Red（RG） and white gastrocnemius（WG） were excised and used to detect intramusclular TG.Real-time PCR was used to detect mRNA of SOCS-3 in RG and WG muscle,Co-immunoprecipitation was used to detect the action of SOCS-3 binding to leptin receptor LRb in RG and WG muscle.Results：1）High-fat diet induced a very quick incraese in rats＇ weight,and increased body weight,blood glucose,triacylglycerol（TG）,leptin and insulin（P〈0.05）,blood leptin and insulin were decreased by endurance exercise in HE group（P〈0.05）.2）TG content in RG muscles：HS group was lower than CS group（P〈0.05）,HE group was higher than HS group（P〈0.05）.WG content in RG muscles：CE group was higher than CS group（P〈0.05）,HE group was higher than HS group（P〈0.05）.3）SOCS-3mRNA expression in RG muscles：CE,HS group was higher than CS group（P〈0.01）.SOCS-3mRNA expression inWG muscles：CE group was higher than CS group（P〈0.01）.4）High-fat diet induced significantly SOCS-3 binding to leptin receptor LRb in RG muscles（P〈0.05）,12-wk endurance exercise decreased the binding（P〈0.05）.Conclusions：1）High-fat diet significantly reduced the TG content of red gastrocnemius,indicating that leptin resistance was prone to be induced by high-fat diet in slow-twitch fibers,high-fat diet weakened the lipid metabolism of slow-twitch fibers;enduran

关 键 词：SOCS-3 高脂膳食 瘦素抵抗 骨骼肌 耐力运动 鼠 动物实验 

分 类 号：G804.7[文化科学—运动人体科学]