蓝刺头多糖B对胰岛素抵抗L6骨骼肌细胞耗糖量及AMPK表达的影响

Effect of Echinops latifolius Tausch Polysaccharide B on glucose consumption and AMPK in insulin-resistance L6 skeletal muscle cells

为了探究蓝刺头多糖B(ETPB)对棕榈酸(PA)诱导的胰岛素抵抗L6骨骼肌细胞耗糖量及腺苷酸活化蛋白激酶(AMPK)表达的影响,体外培养大鼠L6成肌细胞,诱导分化为骨骼肌细胞并进行分化鉴定;采用CCK8法检测细胞存活率,筛选PA和ETPB的安全浓度;葡萄糖氧化酶法检测各组细胞耗糖量;实时荧光定量PCR法检测AMPK mRNA基因表达水平,Western blot法检测AMPK蛋白表达量。结果显示:PA诱导L6骨骼肌细胞发生胰岛素抵抗的最适造模浓度为0.4 mmol/L,ETPB的最大安全浓度为200 mg/mL;ETPB可显著提高胰岛素抵抗L6骨骼肌细胞耗糖量(P<0.05),上调AMPK mRNA表达水平,增加AMPK蛋白表达量。提示:ETPB可以通过提高AMPK基因及蛋白表达而促进胰岛素抵抗L6骨骼肌细胞耗糖,这可能是ETPB改善骨骼肌胰岛素抵抗的作用机制之一。

This study was to explore the effects of Echinops latifolius Tausch polysaccharide B(ETPB)on the sugar consumption and 5′-adenosine monophosphate-activated protein kinase(AMPK)expression in the palmitic acid(PA)-induced insulin resistance L6 skeletal muscle cells.Rat L6 myoblasts cultured in vitro were differentiated into skeletal muscle cells,and the differentiation was confirmed.The CCK8 method was used to measure the cell vialibity,and the safe concentrations of PA and ETPB were screened.The glucose oxidase method was employed to quantify the sugar consumption rate of cells in each group.RT-qPCR was used to detect the mRNA level of AMPK;and Western Blot was used to detect the protein level of AMPK.The results were:The optimal concentration of PA for induction of insulin-resistance in L6 skeletal muscle cells was 0.4 mmol/L,and the maximum safe concentration of ETPB was 200 mg/mL.ETPB significantly increased the sugar consumption(P<0.05),up-regulated mRNA expression in AMPK and increased AMPK protein expression in the insulin-resistance L6 skeletal muscle cells.ETPB promoted glucose consumption in L6 skeletal muscle cells with high insulin-resistance by increasing the levels of mRNA and protein of AMPK,which might be one of the crucial mechanisms underlying the improvement of insulin-resistance by ETPB.