萝卜硫素通过下调微小核糖酸-22改善缺氧诱导的心肌H9c2细胞凋亡

目的:研究萝卜硫素(SFP)对缺氧诱导心肌H9c2细胞损伤的保护作用及其机制。方法:缺氧条件为94%N2、5%CO2和1%O2,将细胞在缺氧培养箱中培养构建缺氧损伤模型。采用SFP处理细胞后,CCK8法、Western blot实验和流式细胞术检测H9c2细胞活力、增殖及凋亡相关指标;观察SFP对缺氧诱导H9c2细胞损伤的保护机制,采用RT-PCR和Western blot方法分析了SFP对H9c2细胞中miR-22/PI3K/AKT信号通路的影响。结果:缺氧诱导H9c2细胞增殖活力的降低,促使细胞凋亡;SFP能明显增强H9c2细胞增殖活力,降低其凋亡;缺氧诱导H9c2细胞中miR-22表达上调,SFP前处理可以明显抑制miR-22表达;miR-22高表达能降低SFP前处理对缺氧诱导H9c2细胞损伤的保护作用,而miR-22低表达诱导SFP对H9c2细胞损伤的保护效应;SFP可通过下调H9c2细胞中miR-22表达增高PI3K和AKT的磷酸化。结论:SFP前处理通过下调miR-22表达改善缺氧诱导的H9c2细胞损伤,其作用机制与PI3K/AKT信号通路活化有关。

Sulforaphane protects rat cardiomyocytes H9c2 from hypoxia-induced apoptosis by down-regulation of microRNA-22

Objective: To investigate the effects of sulforaphane(SFP) on hypoxia-induced H9 c2 cell injury as well as the underlying mechanisms. Methods: The cells were cultured in anoxic incubator under anoxic conditions of 94% N2,5% CO2 and 1% O2 to establish anoxic injury model.After treatment with SPF, cell viability, proliferation and apoptosis were respectively measured by using CCK-8 assay, western blot analysis, and flow cytometry assay. The effects of SFP pretreatment on hypoxia-induced injury were explored. Expression of miR-22 after treatments was determined by stem-loop RT-PCR, and whether SFP affected H9 c2 cells via miR-22/PI3 K/AKT was studied. Results: Hypoxia-induced decreases of cell viability and proliferation as well as increase of apoptosis were attenuated by SFP pretreatments. Hypoxia treatment up-regulated miR-22 expression, and the up-regulation was mitigated by SFP pretreatment. Effects of SFP pretreatment on hypoxia-treated H9 c2 cells were mitigated by miR-22 overexpression while were augmented by miR-22 inhibition. Phosphorylation levels of PI3 K and AKT were increased by SFP through down-regulating miR-22 in hypoxia-treated H9 c2 cells. Conclusions: SFP pretreatment attenuated hypoxia-induced H9 c2 cell injury, possibly through down-regulating miR-22 expression. The PI3 K/AKT pathway was activated by SFP pretreatment via miR-22 in hypoxia-treated cells.