Expression of estrogen-related receptor gamma (ERRgamma) in human skin.

Skin is a non-classical target for estrogens. Despite evidence showing that estrogen receptors (ER) are expressed in skin, there are still extensive gaps in our understanding of how estrogens exert their action in non-reproductive tissues. Estrogen-related receptor gamma (ERRgamma), an orphan member of the nuclear receptor superfamily, shows a strong sequence homology with estrogen receptor alpha but it does not bind estradiol. Here, for the first time, we demonstrate the expression of ERRgamma in adult human skin. ERRgamma mRNA was detected in the keratinocytes and fibroblasts of 8 female donor skins using RT-PCR. The presence of the protein was confirmed using immunohistochemistry on 11 adult human skins and Western Blotting on monolayer-cultures of fibroblasts and keratinocytes from respectively 4 and 2 donors. This study shows that ERRgamma is expressed in human skin and could intervene in a potentially new estrogen signaling pathway in the skin.