The peroxisome proliferator-activated receptor gamma is a nuclear hormone receptor playing a crucial role in adipogenesis and insulin sensitization. Prostaglandin J2 derivatives and the antidiabetic thiazolidinediones are its respective natural and synthetic ligands. The RXR/PPAR gamma heterodimer has also been reported to have important immunomodulatory activities and its pleiotropic functions suggest wide-ranging medical implications.