Peroxisome proliferator-activated receptor alpha, Peroxisome proliferator-activated receptor gamma, Peroxisome proliferator-activated receptor delta (PPAR-α (alpha), PPAR-γ (gamma), PPAR-δ (delta) or PPAR-β/δ (beta/delta))

Peroxisome proliferator-activated receptors (PPARs) are a subgroup of nuclear receptor transcription factors that function as lipid-activated regulators of gene expression. There are three main isoforms in humans: PPAR-α, PPAR-γ, and PPAR-δ (also called PPAR-β/δ). PPAR-α mainly modulates lipid metabolism and is highly expressed in liver, heart, and muscle, controlling fatty acid oxidation and ketogenesis. PPAR-γ is central to adipocyte differentiation, glucose metabolism, and is targeted by thiazolidinedione diabetes drugs. PPAR-δ is more ubiquitous and is involved in fatty acid oxidation, energy expenditure, and modulating inflammation. All PPARs heterodimerize with retinoid X receptor (RXR) and bind to specific DNA sequences—peroxisome proliferator response elements (PPREs)—to regulate expression of metabolic and inflammatory genes. They play significant roles in metabolic diseases, cardiovascular disease, inflammatory conditions, and some cancers.

Other names

PPAR-alphaPPARγPPARδPPARβ/δNR1C1 (PPAR-α)NR1C2 (PPAR-β/δ)NR1C3 (PPAR-γ)Peroxisome proliferator-activated receptor beta (for delta subtype)PPARβ (for delta subtype)hPPARγ (for human PPARγ)

Activation of PPARs by agonists induces conformational changes, promotes heterodimerization with retinoid X receptor (RXR), and recruitment of co-activators to regulate the transcription of target genes involved in fatty acid and glucose metabolism, energy homeostasis, and anti-inflammatory pathways.