Protective role of peroxisome proliferator-activated receptor α agonists in skin barrier and inflammation.

Peroxisome proliferator-activated receptor α (PPARα) is one of the three isoforms of PPARs, which are ligand-activated nuclear transcription factors. PPARα is highly expressed in liver and its agonists are widely used to treat hyperlipidemia. Epidermal keratinocytes express all three isoforms (α, β/δ, and γ) of PPARs and PPARα is particularly important for regulating the epidermal barrier and inflammation. Agonistic ligation of PPARα protects the epidermal barrier function and inhibits the inflammatory response in dermatitis. In this review, we summarize recent topics on the role of PPARα in skin biology and discuss the potential use of topical PPARα agonists for treating atopic dermatitis and other eczemas.