MiR-144-5p reduces myocardial ischemia/reperfusion injury by targeting Atg5 to regulate myocardial autophagy
GAN Peiting
LYU Xiangwei
XU Tongtong
QIN Qiuyu
LING Yuya
LI Shuirong
Abstract：Objective To investigate the mechanism of action of microRNA-144-5p(miR-144-5p)and autophagy-related protein 5(Atg5)for myocardial ischemia/reperfusion(I/R)injury in rats and its relationship with autophagy.Methods A total of 24 male Sprague-Dawley(SD)rats were randomly divided into sham operation group,model group,blank transfection group,and low-expression group,with 6 rats in each group.The rat model of myocardial I/R injury was established by ligation of the left anterior descending coronary artery for 30 min of ischemia followed by 2 h of reperfusion.The low-expression group was injected with adeno-associated virus(AAV)-miR-144-5p antagonist(5×1011 vg),while the blank transfection group was injected with AAV-blank transfection control vector.2,3,5-triphenyltetrazolium chloride(TTC)staining was used to detect the area of myocardial ischemic region;HE staining was applied to observe the pathological changes of myocardial tissue.Western blotting was employed to measure the expression of microtubule-associated protein light chain 3(LC3-B),Atg5,and autophagic degradation substrate P62 in the cardiomyocytes.Dual-luciferase reporter gene assay was conducted to determine the binding effect between miR-144-5p and Atg5.Results Compared with the sham operation group,the model group exhibited significantly increased expression of miR-144-5p in myocardial tissue(2.91±0.12 vs 0.93±0.04,P<0.05),severer myocardial injury,larger myocardial infarction area,elevated P62 expression and decreased expression of Atg5 and LC3-B(P<0.05).Lowering the expression of miR-144-5p attenuated myocardial injury,decreased myocardial infarction area and P62 expression,and up-regulated the expression of Atg5 and LC3-B when compared with the blank transfection group(P<0.05).Dual-luciferase reporter assay revealed that Atg5 and miR-144-5p had a binding interaction.Conclusion MiR-144-5p can target Atg5 to regulate myocardial autophagy,thereby alleviating myocardial I/R injury in rats.
Keywords：myocardial ischemiamyocardial reperfusion injurymicroRNAsautophagy-related protein 5
Publication Date：2026-02-15
Online Publishing Date：2026-03-11(First online date of this platform, not the publication date of the document)
Pages：5( 239-243 )