NOX4 and metabolic dysfunction-associated steatotic liver disease: Furthermore, CD38 deficiency markedly inhibited HFD- or OA-induced the expressions of NOX4, and increased the expression of PPARα, CPT1, ACOX1 and SOD2 in liver tissue and hepatocytes from CD38-/- mice, indicating that CD38 deficiency-mediated the enhancement of fatty acid oxidation and the inhibition of oxidative stress contributed to protecting NAFLD.