Consistently, the mRNA expression levels of fatty acid oxidation-related genes, including ACOX1, CPT1, HMGCS2, and PDK4, were increased in the livers of the MHY2013-treated db/db mice (Figure 4D), indicating that the increased AMPK/β-oxidation signaling contributes to the improvement of hepatic steatosis. The gene discussed is PDK4; the disease is fatty liver disease.