Nuclear hormone receptors in human skin.

Nuclear hormone receptors are of critical importance for skin homeostasis where they modulate cellular metabolism, proliferation, differentiation, cell death, and inflammation. The cutaneous role of the glucocorticoid, androgen, and estrogen receptors was explored initially. In recent years, sequence homology comparisons have uncovered the complete superfamily of related receptors, many of which are also implicated in cutaneous homeostasis. A subgroup of these receptors acts in concert with the retinoid X receptor by heterodimerization and has been successfully targeted for dermatologic therapy; i.e., the retinoic acid receptor and the vitamin D receptor. Ongoing research is aimed at delineating the cutaneous effects of additional members of this subgroup including the peroxisome proliferator-activated receptors and the liver X receptors. The various receptors exert differential effects in skin and can be rationally chosen as drug targets for the treatment of cutaneous pathologies.