激活素A及卵泡抑素对大鼠肾间质成纤维细胞Ⅰ型胶原的影响

Effects of activin A and follistatin on type Ⅰ collagen of cultured rat renal interstitial fibroblasts

目的探讨激活素A(ACT-A)及卵泡抑素(FS)对体外培养的大鼠肾间质成纤维细胞合成I型胶原(ColI)的影响。方法无菌条件下取SD大鼠肾脏髓质,胶原酶消化法进行培养,鉴定为肾间质成纤维细胞后分为3组:不同ACT-A浓度组(A组),不同FS浓度组(F组),30ng/mlACT-A+不同浓度FS组(A+F组),应用免疫组化及RT-PCR法检测培养细胞ColI蛋白及ColImR-NA的表达。结果成功培养了大鼠肾间质成纤维细胞,在本研究浓度范围内,ACT-A促进了大鼠肾间质成纤维细胞ColI蛋白(P<0·01)及ColI mRNA表达(P<0·01),FS能抑制30ng/mlACT-A的上述效应(P<0·01),而单纯FS对大鼠肾间质成纤维细胞ColI蛋白和mRNA的表达无影响(P>0·05)。结论ACT-A可能在肾间质损害的发生发展中起重要作用,补充外源性的FS有可能为治疗肾间质纤维化提供新的思路。

Objective To investigate the stimulating effects of activin A（ACT-A） and follistatin（FS） on the secretion of type I collagen（Col I） and the expression of Col I mRNA of cultured rat renal interstitial fibroblasts in vitro.Methods Rat renal interstitial fibroblasts isolated from normal SD rat renal medulla were cultured in vitro.The cells were divided into three groups：different concentrations of ACT-A（group A）,different concentrations of FS（group F）,and different concentrations of FS plus 30ng/ml ACT-A（group A＋F）.The expression of Col I mRNA in cultured rat renal interstitial fibroblasts was detected by RT-PCR,and the expression of Col I protein in cultured rat renal interstitial fibroblasts was examined by immunocytochemistry.Results Renal interstitial fibroblasts were successfully cultured in vitro.In present study,the expression of Col I mRNA increased significantly in cultured rat renal interstitial fibroblasts after stimulated by ACT-A in dose-dependent manner（P〈0.01）.The secretion of Col I increased obviously when ACT-A was applied to the cultured rat renal interstitial fibroblasts（P〈0.01）.But FS showed no significant effect on Col I mRNA and Col I protein of rat renal interstitial fibroblasts in F group（P〉0.05）.FS could inhibit the effects of ACT-A（30ng/ml） on Col I mRNA and Col I protein of the cultured renal interstitial fibroblasts in dose-dependent manner in A＋F group（P〈0.01）.Conclusions ACT-A may play an important role in the pathogenesis and development of renal fibrosis by increasing the expression of Col I mRNA and Col I protein in rat renal interstitial fibroblasts.FS,as ACT-A inhibitor,can inhibit the effects of ACT-A on the cultured renal fibroblasts.It suggests that FS might be useful in inhibiting renal fibrosis.