The peroxisome proliferator-activated receptors (PPARs) are transcription factors known to play a central role in regulating the storage and catabolism of dietary fats and are also known as lipid sensors of the body. There are three PPAR subtypes: PPARα, PPARγ, and PPARδ. As with other members of the nuclear receptor gene family, the PPARs are ligand-activated transcription factors. Agonist activation of the receptor results in changes in the expression level of mRNAs encoded by PPAR target genes.

The use of PPARγ activators, e.g. rosiglitazone and pioglitazone (glitazones or TZDs), in the treatment of type 2 diabetes has been established due to their ability to lower blood glucose and insulin levels and improve insulin sensitivity. Similarly, PPARα activators, e.g. fenofibrate and clofibrate (fibrates), have been used for more than three decades for their ability to lower plasma triglycerides (TG) and moderately raise HDL-cholesterol.

Currently no marketed drug is available which targets the PPARδ receptor, but several compounds are in exploratory stages providing data that PPARδ is involved in lipid homeostasis.