【摘要】 目的观察百草枯(PQ)诱导人肺上皮HPAEpiC细胞发生上皮间质转化(EMT)作用及其调节机制。方法MTT法计算PQ对HPAEpiC细胞的半数抑制浓度(IC50)值,计算最适合诱导HPAEpiC细胞发生EMT的浓度,Transwell检测证实PQ诱导肺上皮细胞体外迁移能力增强,酶联免疫吸附试验(ELISA)检测转化生长因子-β(TGF-β)变化。实时聚合酶链式反应(Real time-PCR)和免疫印迹法(Western blot)检测细胞EMT标志物及TGF-β下游信号通路变化。结果 PQ对HPAEpiC细胞的IC50值为95.3μmol/L,与DMSO对照组比较,PQ可以诱导肺上皮HPAEpiC细胞形态发生EMT改变,并增加其体外迁移能力,PQ可以促进肺上皮HPAEpiC细胞TGF-β的分泌,并增加其下游Smad2/3、抑制Smad7的蛋白表达;PQ也可以增加间质性标志物N-cadhenrin、波形蛋白(Vimentin)及基质金属蛋白酶2(MMP2)表达,抑制上皮性标志物E-cadherin表达。结论 PQ在促进人肺上皮HPAEpiC细胞死亡的同时促进其向EMT转化,提示PQ诱导肺纤维化的一种新机制。更多还原

【Abstract】 Objective To investigate the mechanisms of paraquat( PQ) induced the epithelial-mesenchymal transition( EMT) in human lung epithelial HPAEpiC cells. Methods HPAEpiC cells IC50 were determined by MTT assay. The TGF- β was assayed by ELASA. The EMT and TGF- β related downstream mRNA and protein were also performed by real time PCR and Western blot in HPAEpiC cells following paraquat treatment. Results PQ IC50 cutoff in HPAEpiC cells is 95. 3 μmol /L. Compared with DMSO control group,PQ could induce lung epithelial to mesenchymal transition morphogenesis change. PQ could also promote the secretion of TGF- β in pulmonary epithelial HPAEpiC cells,increase the downstream Smad2 /3 and inhibit Smad7 expression. PQ could also increase the mesenchymal marker N- cadhenrin,Vimentin and MMP2 expression,however inhibit the expression of E- cadherin. Conclusion PQ could promote human lung epithelial HPAEpiC cell death and furthermore induce " EMT". Our conclusions provided a new mechanism for PQ- induced pulmonary fibrosis.更多还原