Table 1.

Basic features of the three PPAR isoforms.

	Location	Ligands	Coactivators	Primary function	Knockout
PPARα	liver, brown fat, kidney, heart, skeletal muscle	fibrates fatty acids (e.g., oleic acid, palmitic acid) eicosanoids (e.g., arachidonic acid)	p300, c/EBP, SRC-1, PBP, PGC-1, PRIP	lipid catabolism, inflammatory responses, lipoprotein metabolism	hepatomegaly, liver tumors, impaired wound healing, prolonged inflammatory responses, increased adipose tissue
PPARδ	gut, kidney, brain, heart, skeletal muscle	fatty acids, NSAIDS (antagonist)	SRC-1, PBP	fatty acid β-oxidation, bone metabolism, tumorigenesis, vascular integrity	fatal placental defects from abnormal vasculature, small healthy adults
PPARγ	adipose tissue, cartilage, osteoblasts, epithelial cells, prostate, large intestine, monocytes, kidney	thiazolinediones eicosanoids (e.g., 15d-PGJ2, 15-HETE) fatty acids (e.g., DHA, linoleic acid)	p300, c/EBP, SRC-1, PBP, PGC-1, PRIP	adipogenesis, inflammatory response, insulin sensitization, differentiation	embryo-fatal, placenta fails to implant and develop, severe metabolic, hepatic, intestinal, adipogenic, abnormalities