METTL3 Promotes Mitochondrial Dysfunction and Neuronal Ferroptosis in Cerebral Ischemia and Reperfusion Injury through YTHDC1/SLC7A11 Modification.

Abstract

Methyltransferase 3 (METTL3) is dysregulated in various brain disorders. This study aimed to investigate the roles of METTL3 in cerebral ischemia and reperfusion (I/R) injury. Oxygen-glucose deprivation/reoxygenation (OGD/R) was used to establish an in vitro cerebral I/R injury model. mRNA levels were detected by reverse transcription-quantitative PCR. Protein expression was detected by Western blot. Mitochondrial function was detected by immunofluorescence, mitochondrial superoxide (Mitosox) staining, and JC-1 staining. Mitochondrial morphology was detected by transmission electron microscopy. N6-methyladenosine (m6A) levels were detected by m6A assay. The m6A site was verified by luciferase assay. Cellular functions were detected using Cell Counting Kit 8 and propidium iodide staining assays. We found that METTL3 was upregulated in in vitro cerebral I/R injury model. However, inhibition of METTL3 inhibited OGD/R-induced mitochondrial dysfunction and neuronal ferroptosis. Moreover, METTL3 interacted with YTH N6-methyladenosine RNA binding protein C1 (YTHDC1) to promote m6A modification of solute carrier family 7 member 11 (SLC7A11), inhibiting its mRNA and protein stability. Additionally, SLC7A11 knockdown mediated mitochondrial dysfunction and neuronal ferroptosis. In conclusion, METTL3 mediates the progression of cerebral I/R injury through regulating SLC7A11. Therefore, targeting METTL3/YTHDC1/SLC7A11 axis may provide a novel strategy for cerebral I/R injury.