上调Smad7表达对腹膜纤维化大鼠腹膜间皮细胞转分化的影响  

Effect of overexpression of Smad7 on epithelial-mesenchymal transition of mesothelial cells in rat peritoneal fibrosis model

作　　者：孙艳艳[1] 黄锋先[1] 聂静[1] 李晓艳[1] 骆宁[1] 王涌涛[1] 董秀清[1] 余学清[1] 

机构地区：[1]中山大学附属第一医院肾内科,广州510080

出　　处：《中华肾脏病杂志》2007年第12期784-788,共5页Chinese Journal of Nephrology

基　　金：教育部国际合作项目（教外司留【2001】498号）;广东省自然基金（重点）资助项目（2003-36640）;广州市科学委员会重点项目（200422-E0041）

摘　　要：目的探讨上调TGF-β抑制性信号蛋白Smad7表达对大鼠腹膜纤维化模型腹膜间皮细胞转分化的影响。方法30只160～170 g SD雄性大鼠.随机分为4组：正常对照组（n=6）;腹膜纤维化模型组（n=12）：予腹腔注射4.25%腹膜透析液与脂多糖;空载体组（n=6）：模型成功后转染pTRE与pEFpurop-Tet-on质粒;Smad7治疗组（n=6）：模型成功后转染pTRE- m2 Smad7与pEFpurop-Tet-on质粒。第14、28天杀检大鼠,取脏层腹膜组织,用RT-PCR方法检测TGF-B1、α-SMA、E-钙黏蛋白（E-cadherin）基因的表达;用Western杂交或间接免疫荧光的方法检测TGF-β1、Smad7、磷酸化（p）-Smad2/3、α-SMA、E-cadherin的表达。结果与正常对照组比较,模型组TGF-β1、p-Smad2/3及α-SMA的表达显著上调（p〈0.01）;E-cadherin的表达显著下调（P〈0.01）。与模型组、空载体组比较,Smad7治疗组p-Smad2/3及α-SMA表达水平显著下调（P〈0.01）;E-cadherin的表达显著上调,但仍低于正常对照组（P〈0.05）。结论Smad7可通过抑制受体调控信号蛋白Smad2/3的活化,阻止高糖透析液及脂多糖介导的腹膜间皮细胞转分化,从而防止腹膜纤维化的发生和发展。Objective To explore the effect of overexpression of Smad7 on epithelial-mesenchymal transition （EMT） of mesothelial cells in rat peritoneal fibrosis model. Methods Thirty rats were randomly allocated into four groups： normal control group （n=6）, peritoneal fibrosis model group （n=12）, empty vector group （n=6） and Smad7 gene transfer group （n=6）. pTRE-m2 Smad7 plus pEFpurop-Tet-on plasmids plus sonovue or substitution of pTRE-m2 Smad7 with empty vector were injected simultaneously with 4.25% peritoneal dialysate （PDS） and lipopolysaccharide （LPS） on day 15, after intraperitoneal injection of PDS and LIE＇S alone. Peritoneal tissue was dissected out at days 14 and 28 after intraperitoneal injections of PDS and LIE＇S, and the expression patterns of TGF-β1, p-Smad2/3, α-SMA, and E-cadherin were examined by RT-PCR, Western blot or immunofluorescence. Results Comparing with the rats in normal control group, the expression levels of TGF-β1, p-Smad2/3, and α-SMA were increased in model group and vector group （P〈0.01）, but E-cadherin was reduced （P〈0.01）. Smad7 gene transfer group abrogated PDS- and LPS-induced changes in the expression of p-Smad2/3, α-SMA, and E-cadherin （P〈0.01）. Conclusion Blockade of Smad2/3 activation is a central mechanism by which overexpression of Smad7 prevents EMT of mesothelial cells and progressive peritoneal fibrosis in rat peritoneal fibrosis model induced by PDS and LPS.

关 键 词：腹膜透析 纤维化 转化生长因子Β SMAD7 细胞转分化 

分 类 号：R686[医药卫生—骨科学]