Sex Steroid Synthesis in Human Skin In Situ: The Roles of Aromatase and Steroidogenic Acute Regulatory Protein in the Homeostasis of Human Skin

The study, involving skin tissues from 17 patients and scalp skin from 10 male autopsies, explored the synthesis of sex steroids in human skin and their relationship with aromatase (ARO) and steroidogenic acute regulatory protein (StAR) expression. It was found that ARO and StAR expression levels were positively correlated with estrogen and testosterone concentrations, respectively. ARO inhibitors reduced estrogen synthesis, and higher ARO expression was linked to thicker elastic fibers in the skin. Cholesterol administration to keratinocytes increased pregnenolone and testosterone levels. Higher StAR expression was associated with fewer hair follicles in scalp skin, suggesting a connection to hair growth. The study concluded that ARO and StAR are involved in the local synthesis of estrogens and testosterone in human skin, potentially affecting elastic fiber formation and hair growth.