PPAR alpha

Peroxisome proliferator-activated receptor alpha (PPAR alpha, gene PPARA) is the lipid-activated transcription factor that orchestrates fasting responses in liver, heart and muscle. Activated by fatty acids and eicosanoids, it heterodimerizes with RXR on peroxisome proliferator response elements to induce genes for fatty acid beta-oxidation, ketogenesis and lipoprotein metabolism. PPAR alpha is the molecular target of fibrate drugs such as fenofibrate and gemfibrozil, which lower triglycerides and raise HDL cholesterol, and rodent PPAR alpha activation also drives peroxisome proliferation and hepatocarcinogenesis, a species-specific effect relevant to safety assessment. Expression is high in liver, brown adipose tissue, kidney and heart. Recombinant PPAR alpha ligand-binding domain underpins transactivation and coactivator-binding assays used in metabolic drug discovery.