高糖培养人肾小球系膜细胞对TGF-β1、FN、Smad7表达的影响

Effect of High Glucose on Transforming Growth Factor β1,Fibronectin and Smad7 Expression in Human Glomerulus Mesangial Cells

目的:通过观察高糖对人肾小球系膜细胞(HMCs)转化生长因子-β1(TGF-β1)、纤维连接蛋白(FN)、Smad7表达的影响,探讨糖尿病肾病(DN)的发病机制。方法:将HMCs于高糖(30mmol/L)环境培养不同时间后,采用RT-PCR方法检测TGF-β1、FN、Smad7 mRNA表达,Western blotting检测Smad7蛋白的表达,采用ELISA检测TGF-β1、FN蛋白水平,同时以低糖培养作为对照组。结果:高糖培养24h、48h、72h后,TGF-β1 mRNA及蛋白的表达均较低糖培养对照组增加,在48h时达到高峰;FN mRNA及蛋白的表达亦较对照组增加,且呈时间依赖性;而Smad7 mRNA及蛋白表达下降。结论:TGF-β1/Smad信号转导途径负反馈调节Smad7蛋白的表达减少,可能是DN发病过程中的重要环节之一。

Objective:To explore the effect of high glucose on transforming growth factor-β1(TGF-β1),fibronectin(FN)and Smad7 expression in human glomerulus mesangial cells(HMCs).Method:HMCs were grown in DMEM medium containing 30mmol/L high glucose for some time(24h,48h,72h).The expression of TGF-β1,FN,Smad7 mRNA were detected by RT-PCR and western blotting were used to detect the expression of Smad7 while the supernatant level of TGF-β1 and FN were detected by ELISA.Results:In HMCs induced by high glucose,the mRNA and protein expression of TGF-β1 were improved and come to the most after 48h,the mRNA and protein expression of FN were up-regulated in a time-dependent manner,however Smad7 was down-regulated.Conclusion:High glucose can stimulate the expression of extracellular matrix excessively,to some degree,it may owe to the reduction of Smad7 which is a major I-Smad in TGF-β1/Smad signaling pathway.