微RNA-27a介导3T3-L1脂肪细胞胰岛素抵抗的作用机制

The mechanism of miR-27a induced insulin resistance on 3T3-L1 adipocyte cells

目的研究微RNA 27a(miR 27a)介导3T3 L1脂肪细胞胰岛素抵抗的作用机制。方法将3T3 L1细胞诱导分化为脂肪细胞,采用肿瘤坏死因子 α(TNF α)法建立3T3 L1脂肪细胞的胰岛素抵抗模型,检测miR 27a对3T3 L1细胞葡萄糖摄取的影响,蛋白质印迹法(Western Blot)检测miR 27a对胰岛素信号通路的影响。实时荧光定量多聚核苷酸链式反应(qPCR)及双荧光素酶报告基因检测法检测miR 27a的作用靶点。结果miR 27a介导了3T3 L1脂肪细胞的胰岛素抵抗[正常对照组,模型组,miR 27a mimics+模型组,miR 27a inhibitor+模型组四组的吸光度值分别为(2.03±0.20),(1.28±0.27),(1.43±0.20),(1.97±0.18),P<0.01],蛋白质印迹法显示miR 27a抑制了胰岛素信号通路中胰岛素受体底物1(IRS1)及Akt蛋白的磷酸化。qPCR显示miR 27a抑制了过氧化物酶体增殖物激活受体γ(PPARγ)的表达[对照组和mir 27a组的相对值分别为(1.00±0.08)和(0.59±0.14),P=0.0048],双荧光素酶报告基因检测验证了PPARγ为miR 27a的作用靶点[PPARγWT+miR NC,PPARγWT+miR 27a,PPARγMut+miR NC,PPARγMut+miR 27a四组的相对荧光值分别为(5.37±0.80)、(3.17±0.57)、(4.94±0.63)、(4.68±0.74),P<0.01]。结论miR 27a通过抑制胰岛素信号通路及靶向PPARγ介导3T3 L1细胞胰岛素抵抗。

Objective To preliminary study the mechanism of miR 27a induced insulin resistance on 3T3 L1 adipocyte.Methods The insulin resistance modal was induced on 3T3 L1 adipocyte by TNF α.The glucose intake by 3T3 L1 adipocyte was examined and the insulin signal pathway was detected by Western Bolt.At last,Quantitative real time PCR and Dual Luciferase Reporter were used to proved the target of miR 27a,Results miR 27a induced insulin resistance on 3T3 L1 adipocyte(The light absorption val ue of control group,model group,miR 27a mimics+model group,miR 27a inhibitor+modal group were(2.03±0.20),(1.28±0.27),(1.43±0.20),(1.97±0.18),P<0.01),miR 27a mimics inhibit the phosphorylation of IRS1 and Akt.PPARγwas proved to be the target of miR 27a by Dual Luciferase Reporter(The relative value of PPARγWT+miR NC,PPARγWT+miR 27a,PPARγMut+miR NC,PPARγMut+miR 27a were(5.37±0.80)、(3.17±0.57)、(4.94±0.63)、(4.68±0.74),P<0.01).Conclusion miR 27a in duced insulin resistance on 3T3 L1 adipocyte by inhibit insulin signal pathway and targeting PPARγ.