【摘要】 目的:探讨囊性纤维化跨膜转导调节因子(CFTR)对低氧诱导的大鼠心肌H9c2细胞损伤的影响及其作用机制。方法:利用专业缺氧工作站使大鼠心肌H9c2细胞暴露于1%氧含量环境中建立缺氧培养模型。H9c2细胞中CFTR过表达后在缺氧环境中培养,RT-qPCR和Western blot法检测CFTR的mRNA和蛋白表达水平;MTT法检测细胞存活率;Hoechst 33342和Annexin V-FITC/PI染色法检测细胞凋亡;DCF-DA探针检测细胞内活性氧簇(ROS)的生成。结果:1%低氧环境培养可显著诱导H9c2细胞凋亡,同时伴随CFTR mRNA和蛋白水平的下调和ROS的生成增加(P<0.05)。过表达CFTR后低氧诱导的H9c2细胞凋亡以及ROS生成均明显减少;而CFTR蛋白特异性抑制剂CFTRinh-172可显著逆转过表达CFTR的作用。结论:CFTR可能通过抑制ROS生成对抗低氧诱导的心肌细胞凋亡。更多还原

【Abstract】 AIM: To explore the roles of cystic fibrosis transmembrane conductance regulator(CFTR) in hypoxia-induced apoptosis of H9 c2 cardiomyocytes and the underlying mechanisms. METHODS: The rat H9 c2 cardiomyocytes were exposed to a 1% hypoxic environment in a hypoxic chamber. After CFTR overexpression, H9 c2 cardiomyocytes were cultured in a hypoxic environment. The mRNA and protein levels of CFTR were examined by RT-qPCR and Western blot, respectively. The cell viability was measured by MTT assay. The apoptotic rate was determined by Hoechst 33342 and Annexin V-FITC/PI staining, and the production of reactive oxygen species(ROS) was examined by dichloro-dihydro-fluorescein diacetate(DCF-DA) staining. RESULTS: Hypoxic exposure caused the apoptosis of H9 c2 cardiomyocytes, which was accompanied by the down-regulation of CFTR at mRNA and protein levels and over-production of ROS(P<0.05). After CFTR overexpression, the apoptotic rate of the H9 c2 cardiomyocytes induced by hypoxia was significantly reduced, with a prominent inhibition of ROS production(P<0.05). However, pretreatment with CFTRinh-172, a specific inhibitor of CFTR, reversed the protective effect of CFTR overexpression in H9 c2 cardiomyocytes. CONCLUSION: CFTR has a critical role in protecting against hypoxia-induced apoptosis of H9 c2 cells, which may be through inhibiting the generation of ROS.更多还原