Roles of peroxisome proliferator-activated receptor δ in skeletal muscle function and adaptation

Purpose of the review Peroxisome proliferator-activated receptors mediate the transcriptional effects of fatty acids and fatty acid metabolites and regulate many physiological functions including development and metabolism. The roles of peroxisome proliferator-activated receptor alpha and gamma isotypes have been well established, while the functions of the third member of the family, peroxisome proliferator-activated receptor delta, remained unclear until very recently. This review focuses on the physiological functions of the nuclear receptor and especially on its roles in the control of fatty acid metabolism. Recent findings We review very recent data demonstrating that peroxisome proliferator-activated receptor delta plays a central role in the regulation of fatty acid oxidation in several tissues, such as skeletal muscle and adipose tissue, and also that the nuclear receptor is involved in cholesterol metabolism. Summary Use of potent and specific peroxisome proliferator-activated receptor delta agonists and appropriate transgenic animal models revealed the importance of this nuclear receptor in regulation of fatty acid catabolism in skeletal muscle and other tissues. It also indicated the potential of peroxisome proliferator-activated receptor delta as a therapeutic target in pathologies such as metabolic syndrome. However, the effects of peroxisome proliferator-activated receptor delta activation in atherosclerosis and the control of cell proliferation remain to be established.