内脏脂肪素在胰岛素抵抗的L6细胞中对叉头框蛋白1初步作用的研究

Preliminary study on the effect of Visfatin on FoxO1 in insulin resistant L6 cells

目的通过上调内脏脂肪素(Visfatin)表达,检测磷脂酰肌醇3激酶/蛋白激酶B(PI3K/Akt)通路下游信号因子叉头框蛋白1(FoxO1)在L6细胞IR模型中的蛋白表达变化,探讨Visfatin对骨骼肌IR的影响。方法将L6细胞分为正常对照(Con)组、磷脂酸(PA)组、Ins组、PA+Ins组,以确定L6细胞IR模型构建及最佳处理时间。通过DMEM培养液和高浓度PA诱导L6细胞IR模型,过表达Visfatin腺病毒载体,将细胞分为空载对照腺病毒组(PC)、PC+PA组、过表达Visfatin组(Vis组)、Visfatin+PA组(Vis+PA组),Western blot法检测L6细胞PI3K、Akt蛋白表达水平及通路下游信号因子FoxO1的蛋白表达变化。结果与PC组比较,PC+PA组葡萄糖含量升高,Vis组葡萄糖含量降低(P<0.01)。Vis+PA组葡萄糖含量高于Vis组(P<0.01)。与PC组比较,Vis组p-Akt蛋白表达升高,FoxO1蛋白表达降低(P<0.01)。与PC+PA组比较,Vis+PA组p-Akt蛋白表达升高,FoxO1蛋白表达降低(P<0.01)。各组PI3K蛋白表达比较,差异无统计学意义(P>0.05)。结论PA诱导的IR的L6细胞中,过表达Visfatin通过调节PI3K/Akt通路活性,下调FoxO1蛋白表达,促进L6细胞对葡萄糖摄取,改善IR。

Objective To explore the effect of Visfatin on insulin resistance(IR)of skeletal muscle,by detecting the changes of protein expression of downstream signal factor Forkhead box O1(FoxO1)in the phosphatidylinositol 3-kinase protein kinase B(PI3 K/Akt)pathway in L6 cell IR model.cells were divided into normal control(Con)group,phosphatidic acid(PA)group,insulin group(Ins)and PA+Ins group to determine the IR model construction and the best treatment time of L6 cells.the IR model of L6 cells was induced by DMEM culture medium and high concentration PA,and the Visfatin adenovirus vector was overexpressed.The cells were divided into no-load control adeno-associated virus group(PC),PC+PA group,over-expression Visfatin group(Vis group)and Visfatin+PA group(Vis+PA group).Western blot was used to detect the expression levels of PI3 K and Akt protein in L6 cells and the protein expression changes of FoxO1,a key molecule downstream of the pathway.PC group,the glucose content in PC+PA group increased,while that in Vis group decreased significantly(P<0.01).Glucose content in Vis+PA group was higher than that in Vis group(P<0.01).Compared with PC group,the expression of p-Akt protein in Vis group increased and the level of FoxO1 protein decreased(P<0.01).Compared with PC+PA group,p-Akt protein expression in Vis+PA group increased,while FoxO1 protein expression decreased(P<0.01).There was no significant difference in PI3 K protein expression between groups(P>0.05).pression of Visfatin can down-regulate the protein expression of FoxO1 by regulating the activity of the PI3 K/Akt pathway,thereby promoting glucose uptake by L6 cells and improving insulin resistance.