AUTHOR=Wu Yijin , Wu Min , Yang Jue , Li Ying , Peng Wenying , Wu Meifen , Yu Changjiang , Fang Miaoxian 

TITLE=RETRACTED: Silencing CircHIPK3 Sponges miR-93-5p to Inhibit the Activation of Rac1/PI3K/AKT Pathway and Improves Myocardial Infarction-Induced Cardiac Dysfunction

JOURNAL=Frontiers in Cardiovascular Medicine

VOLUME=Volume 8 - 2021

YEAR=2021

URL=https://www.frontiersin.org/journals/cardiovascular-medicine/articles/10.3389/fcvm.2021.645378

DOI=10.3389/fcvm.2021.645378

ISSN=2297-055X

ABSTRACT=The ceRNA network involving circular RNAs (circRNAs) is essential in cardiovascular system. We investigated the underlying ceRNA network involving circHIPK3 in myocardial infarction (MI). After MI model was established, cardiac function was verified and myocardial tissue damage in mice with MI was evaluated. Hypoxia model of cardiomyocytes was used to simulate MI in vivo, and the expression of and targeting relationships among circHIPK3, miR-93-5p and Rac1 were verified. The apoptosis of cardiomyocyte was identified. Gain-and loss-of functions were performed to verify the ceRNA mechanism. MI-modeled mice showed cardiac dysfunction and enlarged infarct size. CircHIPK3 was high-expressed in mouse and cell models of MI. Interference with circHIPK3 reduced infarct size, myocardial collagen deposition and myocardial apoptosis rate, and improved cardiac function. CircHIPK3 sponged miR-93-5p, and miR-93-5p targeted Rac1. Overexpression of miR-93-5p inhibited MI-induced cardiomyocyte injury and eliminated the harmful effect of circHIPK3. CircHIPK3 acted as ceRNA to absorb miR-93-5p, thus promoting the activation of Rac1/PI3K/AKT pathway. We highlighted that interference with circHIPK3 can upregulate miR-93-5p and then inhibit the activation of Rac1/PI3K/Akt pathway, which can improve MI-induced cardiac dysfunction.