Oxidative stress results in cell apoptosis/death and plays a detrimental role in disease development and progression. Stressors alter the miRNA expression profile and miRNAs play a role in the cell response to stress. We previously showed that miR-711 is significantly over-expressed in extended cold ischemia reperfusion injured hearts in heart transplant. In this study, we aimed to investigate the role of miR-711 in cardiac cell damage in response to oxidative stress and how miR-711 is regulated. Rat cardiac cell line H9c2 cells were cultured and exposed to oxidative conditions (Antimycin A (AA), H2O2, CoCl2, or cold hypoxia/reoxygenation (H/R)) in vitro. H9c2 cells were transfected with miR-711 mimics, miR-711 inhibitors, or small interference RNA, using transfection reagents. The expression of miR-711 was measured by quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR). Cell apoptosis/death was detected by flow cytometry and an IncuCyte system. Mitochondrial damage was detected by measuring the mitochondria membrane potential by flow cytometry. Gene expression was detected by qRT-PCR at the mRNA level and Western blotting and immunocytochemistry staining at the protein level. We found that miR-711 was significantly up-regulated in cells treated with H2O2, AA, CoCl2, and cold H/R. Over-expression of miR-711 increased cell apoptosis/death induced by AA and H/R whereas cell death was reduced by miR-711 inhibitors. MiR-711 induced cell death through negative regulation of angiopoietin 1 (Ang-1), fibroblast growth factor 14 (FGF14) and calcium voltage-gated channel subunit alpha1C (Cacna1c) genes. Both knockdown of hypoxia inducible factor 1α (HIF-1α) and inactivation of the nuclear factor kappa-light-chain-enhancer of activated B cells (NFКB) pathway inhibited over-expression of miR-711. Oxidative stress increases the expression of miR-711. Over-expression of miR-711 induces cell apoptosis/death. HIF-1α and NFКB regulate miR-711 in H9c2 cells during oxidative stress. miR-711 is a new target for preventing oxidative stress.

中文翻译：

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miR-711 在心肌细胞中对氧化应激反应的作用及其生物发生：对 H9C2 细胞的研究。

氧化应激导致细胞凋亡/死亡，并在疾病发展和进展中起有害作用。压力源会改变 miRNA 的表达谱，并且 miRNA 在细胞对压力的反应中发挥作用。我们之前表明 miR-711 在心脏移植中延长的冷缺血再灌注损伤心脏中显着过表达。在这项研究中，我们旨在研究 miR-711 在心脏细胞损伤中对氧化应激反应的作用以及 miR-711 是如何被调节的。培养大鼠心脏细胞系 H9c2 细胞并在体外暴露于氧化条件（抗霉素 A (AA)、H2O2、CoCl2 或冷缺氧/复氧 (H/R)）。使用转染试剂，用 miR-711 模拟物、miR-711 抑制剂或小干扰 RNA 转染 H9c2 细胞。通过定量逆转录酶-聚合酶链反应（qRT-PCR）测量miR-711的表达。通过流式细胞术和 IncuCyte 系统检测细胞凋亡/死亡。通过流式细胞仪测量线粒体膜电位来检测线粒体损伤。通过 qRT-PCR 在 mRNA 水平和蛋白质印迹和免疫细胞化学染色在蛋白质水平检测基因表达。我们发现 miR-711 在 H2O2、AA、CoCl2 和冷 H/R 处理的细胞中显着上调。miR-711 的过表达增加了由 AA 和 H/R 诱导的细胞凋亡/死亡，而 miR-711 抑制剂减少了细胞死亡。MiR-711 通过血管生成素 1 (Ang-1)、成纤维细胞生长因子 14 (FGF14) 和钙电压门控通道亚基 alpha1C (Cacna1c) 基因的负调控诱导细胞死亡。低氧诱导因子 1α (HIF-1α) 的敲低和活化 B 细胞 (NFКB) 通路的核因子 kappa-轻链增强子的失活均抑制了 miR-711 的过表达。氧化应激增加了 miR-711 的表达。miR-711 的过表达诱导细胞凋亡/死亡。HIF-1α 和 NFКB 在氧化应激期间调节 H9c2 细胞中的 miR-711。miR-711 是预防氧化应激的新靶点。