CIRKIL Exacerbates Cardiac Ischemia/Reperfusion Injury by Interacting With Ku70
CIRKIL Exacerbates Cardiac Ischemia/Reperfusion Injury by Interacting With Ku70
复制标题
CIRKIL 通过与 Ku70 相互作用加剧心脏缺血/再灌注损伤
DOI：
10.1161/circresaha.121.318992
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发表时间：
2022-03-04
影响因子：
20.1
通讯作者：
Pan, Zhenwei
中科院分区：
文献类型：
--
作者：
Xiao, Hongwen;Zhang, Mingyu;Pan, Zhenwei
背景：Ku 70通过介导DNA双链断裂修复参与多种病理过程。我们以前的研究已经确定了一个高度保守的长非编码RNA心肌缺血再灌注相关Ku 70相互作用lncRNA（CIRKIL），在心肌梗死上调。本研究旨在研究CIRKIL是否通过与Ku 70结合来调节心肌缺血/再灌注（I/R）。方法：采用CIRKIL转基因小鼠和CIRKIL基因敲除小鼠心肌缺血45 min再灌注24 h的方法建立心肌I/R模型。RNA pull-down和RNA免疫沉淀法检测CIRKIL与Ku 70的相互作用。结果：CIRKIL在I/R心肌细胞和H2 O2处理心肌细胞中表达增加。CIRKIL的过表达增加了gamma H（2）A.X的表达，这是DNA双链断裂的特异性标志物，并加重了心肌细胞凋亡，而CIRKIL的敲低则产生了相反的变化。转基因CIRKIL过表达加重了I/R小鼠的心功能不全，扩大了梗死面积，加重了心肌细胞损伤。CIRKIL基因敲除可减轻心肌I/R损伤。从机制上讲，CIRKIL直接与Ku 70结合，随后减少Ku 70的核转位并损害DNA双链断裂修复。Ku 70的同时过表达减轻了CIRKIL过表达诱导的心肌I/R损伤。此外，敲低人CIRKIL显著抑制了H2 O2在成人心室心肌细胞和人诱导多能干细胞衍生的心肌细胞中诱导的细胞损伤。结论：CIRKIL通过调节Ku 70核转位和DNA双链断裂修复，参与I/R损伤的保护作用。因此，CIRKIL可能被认为是一种新的分子靶点，用于治疗与I/R损伤相关的心脏疾病。
Background: Ku70 participates in several pathological processes through mediating repair of DNA double-strand breaks. Our previous study has identified a highly conserved long noncoding RNA cardiac ischemia reperfusion associated Ku70 interacting lncRNA (CIRKIL) that was upregulated in myocardial infarction. The study aims to investigate whether CIRKIL regulates myocardial ischemia/reperfusion (I/R) through binding to Ku70. Methods: CIRKIL transgenic and knockout mice were subjected to 45-minute ischemia and 24-hour reperfusion to establish myocardial I/R model. RNA pull-down and RNA immunoprecipitation assay were used to detect the interaction between CIRKIL and Ku70. Results: The expression of CIRKIL was increased in I/R myocardium and H2O2-treated cardiomyocytes. Overexpression of CIRKIL increased the expression of gamma H(2)A.X, a specific marker of DNA double-strand breaks and aggravated cardiomyocyte apoptosis, whereas knockdown of CIRKIL produced the opposite changes. Transgenic overexpression of CIRKIL aggravated cardiac dysfunction, enlarged infarct area, and worsened cardiomyocyte damage in I/R mice. Knockout of CIRKIL alleviated myocardial I/R injury. Mechanistically, CIRKIL directly bound to Ku70 to subsequently decrease nuclear translocation of Ku70 and impair DNA double-strand breaks repair. Concurrent overexpression of Ku70 mitigated CIRKIL overexpression-induced myocardial I/R injury. Furthermore, knockdown of human CIRKIL significantly suppressed cell damage induced by H2O2 in adult human ventricular cardiomyocytes and human induced pluripotent stem cell-derived cardiomyocytes. Conclusions: CIRKIL is a detrimental factor in I/R injury acting via regulating nuclear translocation of Ku70 and DNA double-strand breaks repair. Thus, CIRKIL might be considered as a novel molecular target for the treatment of cardiac conditions associated with I/R injury.