Department of Cardiovascular Surgery, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, Henan, China.
Aging (Albany NY). 2020 Apr 21;12(8):7232-7247. doi: 10.18632/aging.103072.
The purpose of this study was to reveal the hypothesis that lncRNA X inactive specific transcript (XIST) can participate in the regulation of cardiomyocyte apoptosis in neonatal mice cardiomyocytes (NMCMs) and myocardial infarction (MI) through targeting miR-101a-3p. NMCMs were isolated from neonatal C57BL/6 mice and anoxia was induced in hypoxic chamber. MTT assay and flow cytometry were used to determine proliferation and apoptosis respectively. The target relationship among XIST, miR-101a-3p and was revealed by bioinformatic analysis, luciferase reporter assay, pull-down assay and RNA immunoprecipitation assay. The expression of XIST, miR-101a-3p, and apoptosis-related proteins was determined by qRT-PCR or western blot. MI model was constructed to reveal the role of XIST. We found that XIST was up-regulated in NMCMs under anoxia condition. Moreover, XIST increased FOS expression by sponging miR-101a-3p in anoxia cells. Silencing XIST expression improved cell viability and suppressed apoptosis in vitro and inhibited myocardial infarction by reducing the level of c-FOS and apoptosis-related proteins . Our findings suggest that XIST is involved in MI, modulation of its level can be used as a new strategy or potential target in the treatment of myocardial infarction.
本研究旨在揭示长链非编码 RNA X 失活特异性转录物（XIST）可通过靶向 miR-101a-3p 参与调节新生小鼠心肌细胞（NMCM）和心肌梗死（MI）中心肌细胞凋亡的假说。NMCM 从新生 C57BL/6 小鼠中分离出来，并在缺氧室中诱导缺氧。MTT 测定和流式细胞术分别用于确定增殖和凋亡。通过生物信息学分析、荧光素酶报告基因测定、下拉测定和 RNA 免疫沉淀测定揭示了 XIST、miR-101a-3p 和 之间的靶关系。通过 qRT-PCR 或 Western blot 测定 XIST、miR-101a-3p、 和凋亡相关蛋白的表达。构建 MI 模型以揭示 XIST 的作用。我们发现，在缺氧条件下，NMCM 中的 XIST 上调。此外，XIST 通过海绵 miR-101a-3p 在缺氧细胞中增加 FOS 表达。沉默 XIST 表达可提高体外细胞活力并抑制细胞凋亡，并通过降低 c-FOS 和凋亡相关蛋白水平抑制心肌梗死。我们的研究结果表明，XIST 参与 MI，调节其水平可作为心肌梗死治疗的新策略或潜在靶点。
