The NSUN5-FTH1/FTL pathway mediates ferroptosis in bone marrow-derived mesenchymal stem cells

Abstract

AbstractFerroptosis is a type of cell death induced by the iron-dependent accumulation of lipid hydroperoxides and reactive oxygen species (ROS) in cells. Inhibiting ferroptosis is important for improving the survival of transplanted bone marrow-derived mesenchymal stem cells (BMSCs). Although it is known that NOP2/Sun RNA methyltransferase 5 (NSUN5) post-transcriptionally regulates ferroptosis in BMSCs through RNA methylation, the precise mechanisms underlying these effects have not been reported. In this study, we demonstrate that NSUN5 is downregulated in erastin-induced ferroptosis in BMSCs. Ferroptosis was inhibited by the overexpression ofNSUN5or ferritin heavy chain/light-chain (FTH1/FTL) and was enhanced byNSUN5knockdown. RNA immunoprecipitation experiments revealed that NSUN5 binds to FTH1/FTL, whileNSUN5depletion reduced the levels of 5-methylcytosine inFTH1/FTLRNA and increased intracellular iron concentrations, resulting in the downregulation of glutathione peroxidase 4 (GPX4) and the accumulation of ROS and lipid peroxidation products. Co-immunoprecipitation experiments demonstrated that the recognition ofFTH1andFTLby NSUN5 is dependent on the recruitment of tumor necrosis factor receptor-associated protein 1 (TRAP1). These results suggested that the NSUN5-FTH1/FTL pathway mediates ferroptosis in BMSCs and that the therapeutic targeting of components of this pathway may promote resistance to ferroptosis and improve the survival of transplanted BMSCs.