Estrogen Receptor Alpha, But Not Estrogen Receptor Beta, Is Involved in the Regulation of Hair Follicle Cycling and Epidermis Thickness in Male Mice

The study found that estrogen receptor α (ERα), but not estrogen receptor β (ERβ), was essential for regulating hair follicle cycling and epidermal thickness in male mice. In wild-type and ERβ knockout mice, 17β-estradiol inhibited the transition from telogen to anagen phases and increased epidermal thickness, effects not observed in ERα knockout and double knockout mice. This indicated that ERα mediated these processes. The study involved 4-6 mice per group and suggested potential therapeutic uses for ERα-specific agonists and antagonists in regulating hair growth and treating epidermal conditions. Hair thickness was unaffected by estrogen treatment or ER inactivation.