DJ1 and microRNA‐214 act synergistically to rescue myoblast cells after ischemia/reperfusion injury

Abstract

Ischemia/reperfusion injury is a tissue injury occurring post-reperfusion of tissues with pre-existing ischemia. A good blood supply to tissues aids in the survival of ischemic tissue, however, due to prolonged ischemia the levels of ATP decrease and pH declines leading to acidosis. Reduced ATP leads to an increase in the AMP/ATP ratio, causing cessation of intracellular calcium transport, hence calcium overload and cell death. In this study, we demonstrate the synergistic and antagonistic effect of DJ1 and microR-214 (miR-214) in rescuing myoblast C2C12 cells after ischemia/reperfusion in an in vitro model. Both DJ1 and miR-214 were cloned into a hypoxic inducible expression cassette and transfected into the C2C12 cells. We showed that DJ1 and miR-214 have synergistic effects in reducing intracellular lactate dehydrogenase and intracellular transient calcium levels after reoxygenation compared to control cells, in addition to reducing cell death via necrosis. Western blotting revealed a decrease in autophagosome formation in LC3II/I ratio and an increase in AKT expression in cells transfected with DJ1 and miR-214. Using quantitative real-time PCR, we demonstrated that DJ1 and miR-214 significantly reduced the expression of pro-apoptotic factors and autophagy compared to control. The results indicated DJ1 is an endogenous oxidative stress molecule and miR-214 is a potent inhibitor of the sodium calcium exchanger channel. DJ1 had the greatest effect to inhibiting mitochondrial cell death pathways by possibly acting as a modulator of autophagy. Additionally, we have concluded that miR-214 has an inhibitory effect on extrinsic cell death pathways such as necrosis and autophagy.

Role of the microRNA‑214/Bax axis in the progression of acute liver failure

“…The present results indicated that mir-214 expression was downregulated in the liver tissues from mice stimulated with d-Galn/lPS. it has also been reported that mir-214 serves a suppressive role on extrinsic cell death pathways, such as necrosis and autophagy (33). a previous study indicated that mir-214 improves acute kidney injury in vivo by inhibiting apoptosis (34).…”

The Regulatory Role of Non-coding RNA in Autophagy in Myocardial Ischemia-Reperfusion Injury

“…It was found that the downregulation of miR-204 ( Xiao et al, 2011 ) increased the expression of LC3-II and enhanced autophagy, which aggravated the myocardial cell injury in the I/R model but did not affect the expression of LC3-I. Similarly, miR-214 regulated the ratio of LC3II/I, thus inhibiting autophagy and diminishing cell necrosis and I/R injury ( Ghaderi et al, 2018 ).…”