Peroxisome proliferator-activated receptors (PPARs) and agonists

Obesity and metabolic syndrome are becoming an epidemic worldwide. The medical problems associated with obesity and metabolic syndrome, including insulin resistance, type 2 diabetes mellitus, hypertension, hyperlipidemia and cardiovascular disease have costed a huge medical financial burden. These are also the noxious members of the Taiwan top-ten leading causes of death. PPARs are intra-nuclear receptors. They act as regulators of lipid and glucose metabolism. Fibrates and thiazolidinediones (TZDs) are marketed PPAR α and PPAR γ agonist respectively, and are used in the treatment of metabolic syndrome. Fibrates lower serum triglycerides and increase HDL-cholesterol, while TZDs improve glycemic control and insulin resistance. Both ameliorate inflammation and improve vascular function, and have been proved to decrease cardiovascular risks. Recently, many dual PPAR α/γ agonists, the glitazars have entered phase III clinical trials. Glitazars obtain the beneficial effects of PPAR α and PPAR γ agonists, as well as the side effects of each PPAR due to class effects. Pan-P-PAR and selective PPAR γ modulator (SPPAR γ M) have also gained much attention in the literature; however their clinical applications still need further investigation. Angiotensin receptor antagonists (ARBs) have recently been found to posses selective PPAR γ modulation activity, and can be used to treat multiple components of metabolic syndrome. PPAR β/δ has gained most interests recently because it has unique features other than the PPAR α and PPAR γ activity. We here reviewed some of literatures and summarized them to the readers.