黄芪甲苷对肺炎链球菌体外诱导的肺泡上皮细胞凋亡和炎症反应的影响

Effects of astragaloside Ⅳ on Streptococcus pneumoniae-induced apoptosis and inflammation in alveolar epithelial cells in vitro

目的探讨黄芪甲苷对肺炎链球菌(Streptococcus pneumoniae)诱导的肺泡上皮细胞损伤的影响和机制探讨。方法体外培养正常肺上皮BEAS-2B细胞,用肺炎链球菌处理后,选择黄芪甲苷10、20、40、60μmol/L处理,采用MTT法检测细胞活性。选择黄芪甲苷40μmol/L进行后续实验,流式细胞术检测细胞凋亡;Western blot检测Bcl-2、Bax、Cleaved Cas3、MCP-1、NF-κB蛋白表达;qRT-PCR检测Bcl-2、Bax、Cleaved Cas3、IL-1β、IL-6、TNF-αmRNA表达量;ELISA检测IL-1β、IL-6、TNF-α含量。结果与Con组相比,SP组细胞活性明显降低(P<0.05,P<0.01);与SP组相比,SP+AstragalosideⅣ各组呈剂量效应关系增加细胞活性(P<0.05,P<0.01)。肺炎链球菌感染细胞后促进凋亡,并增加炎症相关因子和蛋白表达。黄芪甲苷降低肺炎链球菌诱导的细胞凋亡率,及炎症相关因子和蛋白表达。结论黄芪甲苷能减轻肺炎链球菌诱导的肺泡上皮细胞炎性损伤,减少细胞凋亡。

To explore the effect of astragaloside Ⅳ on alveolar epithelial cell injury induced by Streptococcus pneumoniae(SP) and its mechanism.Normal lung epithelial BEAS-2B cells were cultured in vitro,and then treated with SP;astragaloside Ⅳ at 10,20,40,60 μmol/L were used to treat the BEAS-2B cells,and the cell viability was detected by MTT.Astragaloside Ⅳ 40 μmol/L was selected for follow-up experiments.Flow cytometry was used to detect cell apoptosis;Western blot were used to detect the protein expression of Bcl-2,Bax,Cleaved Cas3,MCP-1,NF-κB proteins;qRT-PCR was applied to detect the mRNA expression of of Bcl-2,Bax,Cleaved Cas3,IL-1β,IL-6,TNF-α;ELISA was used to detect the levels of IL-1β,IL-6,TNF-α.Compared with the control group,the cell activity of the SP group was significantly reduced(P<0.05,P<0.01);compared with the SP group,the cell activity increased in the SP+astragaloside Ⅳ groups with a dose-effect relationship(P<0.05,P<0.01).SP promoted the apoptosis of alveolar epithelial cells,and up-regulated the expression of inflammation-related factors and proteins;astragaloside Ⅳ could reduce SP-induced apoptosis and the expression of inflammation-related factors and proteins.In conclusion,astragaloside Ⅳ can effectively reduce the inflammatory injury of alveolar epithelial cells induced by Streptococcus pneumoniae and reduce apoptosis of alveolar epithelial cells.