YTHDF2 Promotes Cardiac Ferroptosis via Degradation of SLC7A11 in Cardiac Ischemia–reperfusion Injury
Aims: Myocardial ischemia–reperfusion (I/R) injury severely facilitates cardiomyocyte death and endangers human health. RNA N6-methyladenosine (m6A) methylation modification plays a critical role in cardiovascular diseases. M6A reader YTHDF2 could identify m6a-modified RNA and promote target RNA degradation. Hence, we hypothesized that YTHDF2 impacts I/R injury by regulating RNA stability, in turn revealing the potential regulatory mechanism.  Results: Both the mRNA and protein levels of YTHDF2 were upregulated in I/R mice and hypoxia-reoxygenation (H/R)-induced cardiomyocytes. Silencing endogenous YTHDF2 abrogated cardiac dysfunction and lowered infarct size in I/R mice, and forced expression of YTHDF2 aggravated the above-mentioned adverse pathological process. Consistently, the protective effect of silencing YTHDF2 reappeared in cardiomyocytes induced by H/R and erastin. Furthermore, RNA-seq and RIP revealed that YTHDF2 could recognize the m6A modification sites of ferroptosis-related gene SLC7A11 mRNA to promote its degradation both in vivo and in vitro. Inhibition of SLC7A11 also aggravated cardiac function, infarct size and the release of LDH in I/R mice after silencing YTHDF2. The advantageous effect of si-YTHDF2 in H/R injury was reversed by cotransfection with si-SLC7A11, which substantially exacerbated ferroptosis and the production of ROS. Innovation and Conclusion: All of the obtained data demonstrate that the cardioprotective effects of silencing YTHDF2 are accomplished by enhancing SLC7A11 stability and expression and reducing the level of ferroptosis, furnishing novel potential therapeutic targets for treating ischemic cardiac diseases. Overall design: C57BL/6 mice were injected with the virus solution AAV9 carrying a YTHDF2 shRNA or NC via tail vein injection, and a cTNT promoter conjugated with the GFP gene was constructed. After 4 weeks, I/R surgery was administered.