The purpose of this study was to investigate whether inhibition of DNA (cytosine-5)-methyltransferase 1 (DNMT-1) alleviated ferroptosis through nuclear receptor coactivator 4 (NCOA4)-mediated ferritinophagy during diabetes myocardial (DM) ischemia/reperfusion (I/R) injury (IRI). Rat DM + sham (DS), I/R, and DM + I/R (DIR), H9c2 cell high glucose (HG), hypoxia reoxygenation (H/R), and high-glucose hypoxia reoxygenation (HH/R) models were established. DNMT-1 inhibitor 5-Aza-2’-deoxycytidine (5-aza-CdR) was administered to rat and cell models. The protein level of DNMT-1, NCOA4, FTH, GPX4, Beclin-1, and P62 was detected by western blotting. Compared with normal sham (NS) group, myocardial tissue was injured in DS and I/R models. The level of DNMT-1, NCOA4, and ferroptosis was increased.
Fig: DS, I/R, and DIR rat models construction and verification: A Histopathological changes of myocardium were detected by HE staining. B, CThe TUNEL staining for cell apoptosis rates were detected in different rat groups.D The myocardial infarction area was detected and expressed by AI/AAR (%). ECK-MB in serum was detected. F LDH in serum was detected. Results are presented by means ± SD. n = 8 per group. #P < 0.05 compared with the NS group. *P < 0.05 compared with the DS group. ※P < 0.05 compared with the I/R group.
Moreover, the cell injury was more serious in rat DIR or HH/R model. 5-Aza-CdR could reduce NCOA4-mediated ferritinophagy and myocardial injury in DIR and HH/R models. Moreover, the siRNA for NCOA4 could also reduce the level of ferritinophagy and cell injury in HH/R model. 5-Aza-CdR enhanced the protective effect for NCOA4-siRNA in the process of cell injury. Inhibition of DNMT-1 could reduce ferroptosis during DIR, which the NCOA4-mediated ferritinophagy might be regulated.
Li, W., Li, W., Wang, Y. et al. Inhibition of DNMT-1 alleviates ferroptosis through NCOA4 mediated ferritinophagy during diabetes myocardial ischemia/reperfusion injury. Cell Death Discov. 7, 267 (2021). https://doi.org/10.1038/s41420-021-00656-0