Circular RNA circDhx32 promotes cardiac inflammatory responses in mouse cardiac ischemia-reperfusion injury via binding to FOXO1 competed with AdipoR1
摘要
Ischaemic heart disease is an important cause of death in humans, and resupply of blood to damaged myocardium can exacerbate the risk of cardiac I/R injury. Circular RNAs (circRNAs) play an important role in cardiovascular disease. In this study we investigated the regulatory role of circDhx32 in the progression of I/R injury. Cardiac I/R model was established in mice by ligating the left anterior descending coronary artery (LAD) for 45 min, followed by blood reperfusion for 24 h or 2 weeks. For in vitro study, neonatal mouse ventricular cardiomyocytes were subjected to hypoxia-reoxygenation (H/R) assault. CircDhx32 was significantly upregulated in I/R-treated mice and H/R-treated cardiomyocytes. Cardiomyocyte-specific knockdown of circDhx32 ameliorated the pathological outcomes of cardiac I/R injury including improved cardiac function, reduced infarct size and reduced release of cardiac injury biomarkers. The protective effects of circDhx32 silencing were also observed in cardiomyocytes after H/R. We demonstrated that ALKBH5 functioned as an m6A demethylase, removing the m6A modification sites of circDhx32. Reduced m6A modification inhibited recognition and bindin