MiR-204 regulates cardiomyocyte autophagy induced by ischemia-reperfusion through LC3-II

Abstract

BackgroundAutophagy plays a significant role in myocardial ischemia-reperfusion (IR) injury. So it is important to inhibit autophagy to protect cardiomyocytes besides anti-apoptosis. MiRNA has been demonstrated to protect cardiomyocytes against apoptosis during IR, while whether it has anti-autophagy effect has not been known. The aim of this study was to investigate whether miR-204 regulated autophagy by regulating LC3-II protein, which is the marker of autophagosome during myocardial IR injury.MethodsAdult SD rats were randomized to Control and IR groups. IR group was treated with 30 min ischemia by ligating the left anterior descending coronary artery, followed by 2 h reperfusion by loosing the ligation. The expression of miR-204 was measured by RT-PCR, and LC3 protein was measured by western-blot.ResultsWe found that IR induced cardiomyocytes autophagy, together with down-regulation of miR-204 and up-regulation of LC3-II protein. And, we have found that LC3-II protein was regulated by miR-204, using the method of transferring miR-204 mimic or AMO-204 into the cardiomyocytes, before.ConclusionsThese studies provided evidence that miR-204 played an important role in regulating autophagy through LC3-IIprotein during IR.

PI3K/SGK1/GSK3β signaling pathway is involved in inhibition of autophagy in neonatal rat cardiomyocytes exposed to hypoxia/reoxygenation by hydrogen sulfide

“…The pathophysiologic change underlying IR injury involves necrosis and apoptosis. Autophagy is significantly increased in the myocardium after IR and plays an important role in the IR injury [2] . Autophagy is an evolutionarily conserved lysosomal degradative pathway to remove damaged intracellular constituents for the sake of facilitating cellular homeostasis and promoting cell survival under stressed conditions such as nutrient deprivation and hypoxia [3] .…”

Autophagic program is regulated by miR-325

“…27 miR-204 regulates autophagy through LC3-II. 28 It remains largely unknown as to how autophagy is regulated by miRNAs.…”

MicroRNA-30a Sensitizes Tumor Cells to cis-Platinum via Suppressing Beclin 1-mediated Autophagy

“…Brest et al (26) showed that an miRNA-based alteration in the IRGM gene (encoding a member of the p47 immunity-related GTPase family) regulation can affect the efficacy of autophagy. By studying autophagy induced by ischemia reperfusion, Xiao et al (27) also identified a critical role of miR-204 in regulating autophagy through the LC3-II protein during ischemia reperfusion. However, the role of miRNAs in autophagy-mediated cancer cell chemotherapy resistance remains largely unknown.…”