NOX4 and obesity due to melanocortin 4 receptor deficiency: To explore the effect of NOX4 abundance on hepatic pathophysiology in diet-induced obesity (DIO), we sought to delete Nox4 postnatally in hepatocytes using the Alb-Cre transgene; Nox4 was efficiently deleted in the livers and hepatocytes of Alb-Cre Nox4fl/fl mice (Figure 3, A and B, and Supplemental Figure 5, A and B), but not in other metabolic tissues (Supplemental Figure 5, A and B).