Tang Yu, Wang Yun-Xia, Zhan Yu-Liang, Liu Yan-Feng, Wu Gui-Ping, Wen Li-Dan
Altern Ther Health Med. 2024 Aug 30.
Circular RNAs (circRNAs) have emerged as essential regulators in cardiovascular disease, including acute myocardial infarction (AMI). This study investigated the role of circRNA Pum1_0014 in myocardial infarction (MI) and its underlying mechanisms using an H9C2 cell model. Through Sanger sequencing, nucleic acid electrophoresis, RNase R, and transcriptional inhibition experiments, Pum1_0014 was identified as a novel circRNA. The cell localization of circRNA Pum1_0014 was detected by qPCR and fluorescence in situ hybridization, and the results revealed that circRNA Pum1_0014 is predominantly located in the cytoplasm. StarBase (URL: http://starbase.sysu.edu.cn/) and TargetScan (URL: https://www.targetscan.org/vert_80/) were used to predict circRNA Pum1_0014 targeting miRNAs and miRNA targeting mRNA, and the results identified miR-146a-5p as a potential target of Pum1_0014, which in turn targets NF2. The plasmid encoding the mutant circRNA Pum1_0014 or the 3'UTR mutant NF2 was constructed, and the interaction between Pum1_0014 and miR-146a-5p or miR-146a-5p and NF2 was detected by luciferase reporter gene assay. The results confirmed the interactions between Pum1_0014, miR-146a-5p, and NF2. In the MI cell model, upregulation of circRNA Pum1_0014 and NF2 and downregulation of miR-146a-5p were observed. Knockdown of circRNA Pum1_0014 inhibited NF2 expression and activated the VEGF/PAK1 pathway, reducing cardiomyocyte apoptosis. Conversely, inhibition of miR-146a-5p and overexpression of NF2 had opposite effects. These findings suggest that circRNA Pum1_0014 acts through the miR-146a-5p/NF2 axis to reduce cardiomyocyte apoptosis in MI via the VEGF/PAK1/NF2 pathway.
环状RNA（circRNAs）已成为心血管疾病（包括急性心肌梗死，AMI）中的重要调节因子。本研究使用H9C2细胞模型研究了circRNA Pum1_0014在心肌梗死（MI）中的作用及其潜在机制。通过桑格测序、核酸电泳、RNase R和转录抑制实验，Pum1_0014被鉴定为一种新型circRNA。通过qPCR和荧光原位杂交检测circRNA Pum1_0014的细胞定位，结果显示circRNA Pum1_0014主要位于细胞质中。使用StarBase（网址：http://starbase.sysu.edu.cn/）和TargetScan（网址：https://www.targetscan.org/vert_80/）预测circRNA Pum1_0014靶向的miRNA以及miRNA靶向的mRNA，结果确定miR-146a-5p为Pum1_0014的潜在靶点，而miR-146a-5p反过来靶向NF2。构建了编码突变型circRNA Pum1_0014或3'UTR突变型NF2的质粒，并通过荧光素酶报告基因检测法检测Pum1_0014与miR-146a-5p或miR-146a-5p与NF2之间的相互作用。结果证实了Pum1_0014、miR-146a-5p和NF2之间的相互作用。在MI细胞模型中，观察到circRNA Pum1_0014和NF2上调，miR-146a-5p下调。敲低circRNA Pum1_0014可抑制NF2表达并激活VEGF/PAK1通路，减少心肌细胞凋亡。相反，抑制miR-146a-5p和过表达NF2则产生相反的效果。这些发现表明，circRNA Pum1_0014通过miR-146a-5p/NF轴，经由VEGF/PAK1/NF2通路减少MI中的心肌细胞凋亡。
