PPARA and obesity due to melanocortin 4 receptor deficiency: Because obesity-induced UGT expression in mouse liver and the induction was associated with AhR, CAR, PPAR-α, PXR, Nrf2, and peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) up-regulation,[10] this may have a significant impact on the metabolism of bilirubin at different stages of hypertriglyceridemia.