Prdx4 and superoxide dismutase 1 (Sod1) double-knockout mice (Prdx4−/y;Sod−/−) show more severe liver phenotypes, such as aggravated liver steatosis and liver failure, at a relatively young age compared with those of wild-type, Prdx4−/y, and Sod−/− [93]. Here, SOD1 is linked to fatty liver disease.