【摘要】 目的研究高浓度氧对胎鼠肺泡Ⅱ型上皮细胞(AECⅡ)EGF、TGFβ1信号通路及呼吸抑制拮抗基因Sprouty2表达的影响。方法将原代培养的胎鼠AECⅡ随机分为空气和高氧两个组,观察细胞形态学变化;Annexin V和PI双标记流式细胞仪检测细胞凋亡;实时定量PCR法检测细胞Sprouty2 mRNA的表达;Western blot法检测细胞Sprouty2、EGF受体、磷酸化EGF受体(Tyr1148)、磷酸化EGF受体(Tyr845)、TGF-βⅡ型受体蛋白表达。结果 AECⅡ暴露于高氧后,细胞贴壁不紧,长势欠佳。高氧组早期凋亡细胞明显增多(P<0.05);高氧暴露后24和36 h,Sprouty2 mRNA及蛋白表达随高氧暴露时间延长而增加(P<0.05);高氧暴露后24和36 h,EGF受体、磷酸化EGF受体(Tyr1148)、磷酸化EGF受体(Tyr845)表达均减少,而TGF-βⅡ型受体蛋白表达增加(P<0.05)。结论高氧暴露通过下调EGF信号和上调TGFβ1信号,进而使Sprouty2表达增加,增加的Sprouty2与AECⅡ凋亡相关。更多还原

【Abstract】 Objective To study imbalance between EGF and TGFβ1 signal in fetal rat alveolar epithelial type 2 cell exposed to oxygen.Methods Primary fetal rat type 2 alveolar epithelial cells were divided into air group and O2 group.Cell apoptosis was measured by FACS.Sprouty2,EGF receptor,phospho-EGF receptor(Tyr1148),phospho-EGF receptor(Tyr845)and TGF-βⅡ receptor were tested by Western blot.Sprouty2 mRNA was measured by real-time PCR.Results Compared with air group,there was increased cell apoptosis in O2 group according to FACS.Sprouty2 mRNA and protein were increased in O2 group.EGF receptor,phospho-EGF receptor(Tyr1148),phospho-EGF receptor(Tyr845)were decreased in O2 group compared with air group while TGF-βⅡ receptor expression was increased in O2 group compared with air group.Conclusions EGF which can decrease Sprouty2 expression is downregulated in fetal rat alveolar epithelial type 2 cells exposed to oxygen.TGFβ1 which can increase Sprouty2 expression is upregulated in fetal rat alveolar epithelial type 2 cell exposed to oxygen.Both of these 2 mechanisms cause further rising of Sprouty2.更多还原