Androgens and Androgen Receptor Action in Skin and Hair Follicles

The document from 2018 reviews the roles of androgens and the androgen receptor (AR) in skin and hair follicle physiology and pathology, particularly focusing on androgenetic alopecia (AGA). It explains how skin cells synthesize androgens, the involvement of enzymes in skin steroidogenesis, and the molecular pathophysiology of AGA, including the role of type 2 5α-reductase, AR coactivators, and deregulated paracrine factors in the dermal papilla. The review also discusses the importance of androgens in regulating hair growth, sebum production, and other physiological effects, as well as the potential for new treatments targeting AR and Wnt signaling. It notes that androgens and AR are crucial in AGA, with elevated 5α-reductase activity in men and decreased aromatase activity in women being significant, and that AR gene polymorphisms and methylation patterns may influence AGA. The document also mentions investigational treatments for AGA, including a 'Hair Stimulating Complex' and a molecule that activates the Wnt pathway, both showing promise in clinical trials. Despite decades of study, the molecular mechanisms of androgen involvement in skin disorders are not fully understood, but ongoing research is contributing to the development of targeted therapies.