从SIRT1探讨白藜芦醇抑制肾小球足细胞表型改变的作用机制

摘要

目的 探讨SIRT1在白藜芦醇抑制肾小球足细胞表型改变中的作用,研究白藜芦醇维持足细胞表型的重要机制.方法 体外分化条件下培养小鼠足细胞10天,用TGF-β1诱导作为研究模型,分别用白藜芦醇、SRT1720和EX527以及白藜芦醇与EX527联合干预等.采用RT-PCR和Western blot法等检测足细胞α-平滑肌肌动蛋白(α-smooth muscle-actin,α-SMA)、snail等分子基因表达;NEPH1、结蛋白Desmin和α-SMA等分子蛋白表达.结果 TGF-β1诱导的足细胞α-SMA、snail基因表达较正常组增高,白藜芦醇、SRT1720干预组则较模型组降低.模型组NEPH1蛋白表达较正常组显著降低,而Desmin和α-SMA蛋白表达水平则显著增高.白藜芦醇组NEPH1蛋白表达较模型组显著上调,Desmin和α-SMA表达显著降低,白藜芦醇与EX527同时干预或EX527单独干预,对足细胞表型分子表达则未表现出显著干预作用.结论 激活SIRT1是白藜芦醇显著抑制TGF-β1诱导的足细胞表型异常的重要机制.%Objective To investigate the role of SIRT1 (silent mating type information regulation 2 homolog 1) in the inhibition of podocyte transdifferentiation by resveratrol,and explore the mechanism of resveratrol to maintain podocyte phenotype.Methods Immortalized mouse podocytes were cultured under differentiating conditions for 10d in vitro.The podocytes incubated with TGF-β1 were served as research model,and they were treated with resveratrol or SRT1720 or EX527 or resveratrol combined with EX527,respectively.The genetic expressions of α-SMA and snail were verified by RT-PCR.The protein levels of NEPH1,α-SMA and Desmin were determined by western-blotting.Results Compared with normal group,the genetic expression of o-SMA and snail in the podocytes induced with TGF-β1 (model group) increased.While the resveratrol and SRT1720 intervention group was lower than that of the model group.The protein expression of NEPH1 decreased significantly in model group compared with normal group,however,the expression of α -SMA and Desmin increased obviously.Besides,the expression of NEPH1 protein in Resveratrol group was significantly higher than that of the model group,while the expression of α-SMA and Desmin decreased significantly.In co-ordinated intervention of resveratrol and EX527 group and EX527 group,the expression of podocyte phenotype molecules including NEPH1,α-SMA and Desmin all showed no significant difference with model group.Conclusion Activating SIRT1 is an important mechanism of resveratrol to significantly inhibit transdifferentiation of podocytes induced by TGF-β1.