A NAD(P)H-dependent oxidoreductase that acts as a key inhibitor of ferroptosis (PubMed:31634899, PubMed:31634900, PubMed:35922516, PubMed:36788244, PubMed:37957306, PubMed:39881208, PubMed:37739993, PubMed:39160155, PubMed:38414669, PubMed:40233740). At the plasma membrane, catalyzes reduction of coenzyme Q/ubiquinone-10 to ubiquinol-10, a lipophilic radical-trapping antioxidant that prevents lipid oxidative damage and consequently ferroptosis (PubMed:31634899, PubMed:31634900, PubMed:37739993, PubMed:39160155, PubMed:38414669, PubMed:40233740). Acts in parallel to GPX4 to suppress phospholipid peroxidation and ferroptosis (PubMed:31634899, PubMed:31634900). This anti-ferroptotic function is independent of cellular glutathione levels (PubMed:31634899, PubMed:31634900). Also acts as a potent radical- trapping antioxidant by mediating warfarin-resistant vitamin K reduction in the canonical vitamin K cycle: catalyzes NAD(P)H-dependent reduction of vitamin K (phylloquinone, menaquinone-4 and menadione) to hydroquinone forms (PubMed:35922516, PubMed:36788244). Hydroquinones act as potent radical-trapping antioxidants inhibitor of phospholipid peroxidation and ferroptosis (PubMed:35922516). May play a role in mitochondrial stress signaling (PubMed:26689472). Upon oxidative stress, associates with the lipid peroxidation end product 4-hydroxy-2- nonenal (HNE) forming a lipid adduct devoid of oxidoreductase activity, which then translocates from mitochondria into the nucleus triggering DNA damage and cell death (PubMed:26689472). Capable of DNA binding in a non-sequence specific way (PubMed:15958387). {ECO:0000269|PubMed:15958387, ECO:0000269|PubMed:26689472, ECO:0000269|PubMed:31634899, ECO:0000269|PubMed:31634900, ECO:0000269|PubMed:35922516, ECO:0000269|PubMed:36788244, ECO:0000269|PubMed:37739993, ECO:0000269|PubMed:37957306, ECO:0000269|PubMed:38414669, ECO:0000269|PubMed:39160155, ECO:0000269|PubMed:39881208, ECO:0000269|PubMed:40233740}. This is the function of Ensembl gene identifier ENSG00000042286 (AIFM2, AIF family member 2, ferroptosis suppressor).