PPAR-γ Agonists and Their Role in Primary Cicatricial Alopecia

Peroxisome proliferator-activated receptor gamma (PPAR-gamma) is a ligand- activated nuclear receptor that regulates the transcription of various genes. PPAR-gamma plays roles in lipid homeostasis, sebocyte maturation, and peroxisome biogenesis and has shown antiinflammatory effects. PPAR-gamma is highly expressed in human sebaceous glands. Disruption of PPAR-gamma is believed to be one of the mechanisms of primary cicatricial alopecia (PCA) pathogenesis, causing pilosebaceous dysfunction leading to follicular inflammation. In this review article, we discuss the pathogenesis of PCA with a focus on PPAR-gamma involvement in pathogenesis of lichen planopilaris (LPP), the most common lymphocytic form of PCA. We also discuss clinical trials utilizing PPAR-agonists in PCA treatment.