过氧化物酶体增殖物激活受体γ激动剂对TGF-β_1诱导肾成纤维细胞细胞外基质表达的影响

Effects of peroxisome proliferators-activated receptor γ agonists on TGF-β_1-induced extracellular matrix expression in renal fibroblasts

目的:研究过氧化物酶体增殖物激活受体γ(PPARγ)激动剂对转化生长因子β1(TGFβ1)致肾间质纤维化作用的影响,探讨其抗肾间质纤维化的潜在作用。方法:体外培养大鼠肾成纤维细胞株(NRK/49F),利用逆转录聚合酶链反应(RTPCR)观察PPARγ配体15dPGJ2及其激动剂曲格列酮和齐格列酮对TGFβ1诱导的α平滑肌肌动蛋白(αSMA)、结缔组织生长因子(CTGF)、纤维连结蛋白(FN)和Ⅲ型胶原(ColⅢ)mRNA表达的影响,利用WesternBlot方法观察PPARγ激动剂对TGFβ1诱导的FN蛋白表达的影响。结果:TGFβ1能显著增加NRK/49F细胞CTGF、FN和ColⅢmRNA表达,并呈剂量依赖和时间依赖效应。与TGFβ1刺激组相比,10μM15dPGJ2、曲格列酮和齐格列酮预处理组αSMA、CTGF、FN和ColⅢmRNA表达量显著减少,FN蛋白表达量显著下降。结论:PPARγ激动剂可抑制TGFβ诱导的肾间质成纤维细胞CTGF表达和细胞外基质(ECM)合成。

Objective： To study the effects of peroxisome proliferators-activated receptor γ （PPARγ） agonists on TGF-β1-induced fibrotic response in the renal fibroblasts, so as to investigate its effects on preventing tubulointerstitial fibrosis. Methodology： In cultured rat renal fibroblasts cell line （NRK/49F cells） , the effects of PPARγ ligand 15d-PGJ2 and its agonists troglitazone and ciglitazone on the level of TGF-β1-indued α-smooth muscle actin （α-SMA）, connective tissue growth factor （CTGF） , fibronectin （FN） and collagen type Ⅲ （Col Ⅲ ） mRNA expression was observed by reverse transcriptase-polymerase chain reaction （RT-PCR）. The effects of PPARγ agonists on the level of FN protein expression induced by TGF-β1 were observed by Western Blot. Results：In NRK/49F cells, TGF-β1 enhanced CTGF, FN and Col Ⅲ mRNA expression in a dose-and time-dependent manner. The level of α-SMA, CTGF, FN, Col Ⅲ mRNA and FN protein expression in 15d-PGJ2, troglitazone and ciglitazone-pretreated groups, respectively, were significantly decreased compared with TGF-β1-stimulated group. Conclusion： PPARγ agonists may inhibit TGF-β1-induced CTGF expression and extracellular matrix sythesis in the renal fibroblasts.