This study was aimed at determining the roles and functions of lncRNA XIST/miR-545-3p/G3BP2 axis during hypoxia/reoxygenation (H/R)-induced H9C2 cell apoptosis. H9C2 cells were distributed into two groups, the H/R injury and control groups. High-throughput lncRNA sequencing was applied in the determination of differentially expressed lncRNAs between H/R-induced H9C2 cells and normal H9C2 cells. Real-time polymerase chain reactions (RT-PCR) were used to confirm the expression levels of lncRNA XIST in H/R-induced H9C2 cells. H9C2 cells were then transfected with lncRNA XIST recombinant plasmid (lncRNA XIST), sh-LINC XIST, agomiR-545-3p, antagomiR-545-3p, pcDNA-G3BP2, sh-G3BP2, and a corresponding negative control (NC). Bioinformatic analyses revealed that MiR-545-3p was a target for lncRNA XIST. This finding was confirmed by dual-luciferase reporter assay. The degree of cell apoptosis was evaluated by a flow cytometer. RT-PCR and western blot were performed to assess the apoptotic-related proteins in each group. A total of 859 differentially expressed lncRNAs (up-regulated = 502, down-regulated = 357) were identified. LncRNA XIST was found to be down-regulated in H/R-induced H9C2 cells while miR-545-3p was distinctly up-regulated. miR-545-3p was established to be a direct target for LncRNA XIST. LncRNA XIST significantly enhanced the apoptotic rate, while its inhibition suppressed the apoptotic rate. AgomiR-545-3p partially blocked the lncRNA XIST and enhanced the apoptosis of H/R-induced H9C2 cells. Moreover, miR-545-3p was shown to be a direct target for G3BP2. The overexpression of G3BP2 partially reversed the apoptotic effects of miR-545-3p on H/R-induced H9C2 cells. lncRNA XIST/miR-545-3p/GBP2 was found to be an apoptotic regulator in H/R-induced H9C2 cells.

中文翻译：

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lncRNA XIST敲低通过调节miR-545-3p/G3BP2抑制缺氧/复氧（H/R）诱导的H9C2细胞凋亡


本研究旨在确定lncRNA XIST/miR-545-3p/G3BP2轴在缺氧/复氧（H/R）诱导的H9C2细胞凋亡过程中的作用和功能。 H9C2细胞分为两组，H/R损伤组和对照组。应用高通量lncRNA测序测定H/R诱导的H9C2细胞与正常H9C2细胞之间差异表达的lncRNA。使用实时聚合酶链反应（RT-PCR）来确认H/R诱导的H9C2细胞中lncRNA XIST的表达水平。然后用lncRNA XIST重组质粒（lncRNA XIST）、sh-LINC XIST、agomiR-545-3p、antagomiR-545-3p、pcDNA-G3BP2、sh-G3BP2和相应的阴性对照（NC）转染H9C2细胞。生物信息学分析表明 MiR-545-3p 是 lncRNA XIST 的靶标。这一发现得到了双荧光素酶报告基因测定的证实。通过流式细胞仪评估细胞凋亡的程度。进行RT-PCR和蛋白质印迹来评估各组中的凋亡相关蛋白。总共鉴定出 859 个差异表达的 lncRNA（上调 = 502，下调 = 357）。发现 LncRNA XIST 在 H/R 诱导的 H9C2 细胞中下调，而 miR-545-3p 明显上调。 miR-545-3p 被确定为 LncRNA XIST 的直接靶标。 LncRNA XIST 显着提高了细胞凋亡率，而其抑制作用则抑制了细胞凋亡率。 AgomiR-545-3p部分阻断lncRNA XIST并增强H/R诱导的H9C2细胞的凋亡。此外，miR-545-3p被证明是G3BP2的直接靶标。 G3BP2 的过表达部分逆转了 miR-545-3p 对 H/R 诱导的 H9C2 细胞的凋亡作用。 lncRNA XIST/miR-545-3p/GBP2被发现是H/R诱导的H9C2细胞的凋亡调节因子。