TGFβ1-Smad信号通路参与IL-33诱导的A549细胞上皮间质转化

Transforming Growth Factor Beta 1-Smad Signal Pathway Participates in the Epithelial Mesenchymal Transition of A549 Cells Induced by IL-33

目的:探讨TGFβ1-Smad信号通路在IL-33诱导的A549细胞上皮间质转化中的作用。方法:体外培养人肺泡上皮细胞来源的A549细胞株,将传代培养的细胞分为对照组、TGFβ受体抑制剂(LY2109761)组、IL-33组、IL-33+TGFβ受体抑制剂(LY2109761)组。给予相应处理,24h后收集各处理组细胞。RT-PCR和Western blot检测转化生长因子β1(TGFβ1)、上皮细胞标志物E钙黏素(E-cad)和间质细胞标志物α-平滑肌肌动蛋白(α-SMA)的表达水平。Western-blot检测Smad信号通路Smad3、p-Smad3的表达水平。结果:与对照组比较,TGFβ受体抑制剂组Smad3蛋白,p-Smad3蛋白,TGFβ1、E-cad、α-SMA的mRNA及蛋白表达表达水平均未见明显变化(P>0.05);与对照组比较,IL-33组Smad3蛋白表达水平无明显变化(P>0.05),但p-Smad3蛋白表达水平明显升高(P<0.05),TGFβ1mRNA及蛋白表达明显升高(P<0.05),E-cad mRNA及蛋白表达明显降低(P<0.05),α-SMA mRNA及蛋白表达明显升高(P<0.05);IL-33+TGFβ受体抑制剂组与IL-33组比较,Smad3蛋白表达水平无明显变化(P>0.05),但p-Smad3蛋白表达水平明显降低(P<0.05),TGFβ1的mRNA及蛋白表达未见明显改变(P>0.05),E-cad的mRNA及蛋白表达明显升高(P<0.05),α-SMA的mRNA及蛋白表达水平明显降低(P<0.05)。结论:TGFβ1-Smad信号通路参与IL-33诱导的A549细胞上皮间质转化。

Objective：To investigate the effect of transforming growth factor（TGF）β1-Smad signal pathway on the epithelial-mesenchymal transition（EMT）of A549 cells induced by IL-33.Methods：The alveolar epithelial cell line-A549 cells cultured in vitro were divided into 4groups：the control group,the TGF-βreceptor typeⅠ/Ⅱdual inhibitor（LY2109761）group,the IL-33 group,the IL-33＋TGF-βreceptor typeⅠ/Ⅱdual inhibitor（LY2109761）group.Given the corresponding processing,cells were collected after 24 hours.RT-PCR and Western-blot were utilized to evaluate the expression of TGFβ1,E-cad andα-SMA.Western-blot was utilized to evaluate the expression of Smad3 and p-Smad3.Results：There was no difference between the control group and TGF-βreceptor typeⅠ/Ⅱdual inhibitor group（P〉0.05）in the expression of Smad3,p-Smad3,TGFβ1,E-cad andα-SMA.Compared with the control group,theexpression of Smad3 in the IL-33 group did not change significantly（P〈0.05）,while the expression of p-Smad3,TGFβ1,α-SMA significantly increased（P〈0.05）and the expression of E-cad markedly decreased（P〈0.05）.Compared with the IL-33 group,there was no differrnce between the expressions of Smad3 and TGFβ1in IL-33＋TGF-βreceptor type Ⅰ/Ⅱ dual inhibitor group（P〈0.05）,but the expression of p-Smad3andα-SMA significantly decreased（P〈0.05）,while the expression of E-cad significantly increased（P〈0.05）.Conclusion：TGFβ1-Smad signal pathway participates in the EMT of A549 cells induced by IL-33.