胰岛素对高脂诱导胰岛素抵抗L6细胞固醇调节元件结合蛋白-1c表达的影响  

Effects of insulin intervention on SREBP-1c expressions in L-6 myotubes with FFA-induced insulin resistance

作　　者：孙婧[1] 汤孙寅焱[1] 陈莹莹[1] 朱大龙[1] 毕艳[1] 

机构地区：[1]南京大学医学院附属鼓楼医院内分泌科,210008

出　　处：《临床内科杂志》2015年第6期413-416,共4页Journal of Clinical Internal Medicine

基　　金：南京大学医学院附属鼓楼医院青年科研启动基金资助项目（QJ2012005）

摘　　要：目的探讨胰岛素对高脂诱导胰岛素抵抗的骨骼肌细胞脂代谢及相关基因、蛋白表达的影响和机制。方法 L6成肌细胞诱导分化后行棕榈酸干预建立胰岛素抵抗模型，胰岛素干预后，分别检测3组脂代谢相关基因和蛋白表达的变化。结果与对照组比较，高脂组诱导胰岛素抵抗后，固醇调节元件结合蛋白（SREBP）-1cmRNA和蛋白水平明显升高，IRS-1mRNA和蛋白水平明显降低。胰岛素干预后，SREBP-1c表达下降，IRS-1表达升高。3组中肿瘤坏死因子（TNF）-α、star3mRNA表达无明显变化。结论高脂诱导骨骼肌胰岛素抵抗下，胰岛素干预可能通过影响脂质代谢通路中关键的转录因子改善胰岛素抵抗。Objective To observe the effects of insulin intervention on lipid metabolism in L-6 myotubes with FFA-induced insulin resistance. Methods L6 cell line was cultured and differentiated into myotubes. After 12-16h of the starved condition in L-DMEM with 1% FFA-free BSA, L-DMEM with 0.4 mM PA and 5% FFA-free BSA was added to the myotubes for 24 h, the content of glucose in the supernatant was detected by using glucose oxidase method. Myotubes of PA were then replaced by L-DMEM with 10 nmol insulin for 24 h,The mRNA and protein related with lipid metabolism were measured by RT-PCR and Western blotting. Results In PA group, the mRNA expression and the protein level of SREBP-1c was up-regulated, IRS-1 mRNA expression and protein level wasdecreased（P 〈 0.05）. After insulin intervention,SREBP-1c expression was down-regulated, IRS-1 expression was increased（P 〈 0.05）. The mRNA expressions of TNF-α and stat3 in the control group, PA group and insulin group were not changed （ P 〉 0. 05 ）. Conclusion Insulin intervention may relieve insulin resistance potentially through inhibition of SREBP-1c in skeletal muscle.

关 键 词：骨骼肌细胞 棕榈酸 胰岛素抵抗 SREBP-1C 

分 类 号：R587.1[医药卫生—内分泌]