Peroxisome proliferator-activated receptor α (PPARα) is a ligand-activated transcription factor involved in the regulation of lipid homeostasis. Activation of PPARα results in expression of a variety of genes, particularly those involved in fatty acid β-oxidation, binding, and transport. Ciprofibrate activates PPARα with an EC50 value of 20 μM and only marginally affects PPARγ (EC50 = >300 μM). It has been shown to lower adipose tissue weight and reduce plasma insulin concentrations in obese rats and has been used clinically in the treatment of dyslipidemia. Ciprofibrate reportedly stimulates cholesteryl ester transfer protein expression and improves the flow of cholesterol through the indirect reverse cholesterol transport system, preserving plasma HDL.
