Androgen Receptor-Mediated Paracrine Signaling Induces Regression of Blood Vessels in the Dermal Papilla in Androgenetic Alopecia

The study examined the role of androgen receptor (AR) signaling in the regression of blood vessels in the dermal papilla (DP) in androgenetic alopecia (AGA), or male pattern baldness. The researchers found that AR levels were higher in the DP of balding scalp in AGA patients. Transcriptome analysis revealed abnormalities in the microvasculature of the DP in balding scalp compared to nonbalding scalp. The study also showed that blood vessels regress in the DP during the early stages of hair follicle miniaturization in AGA development. The researchers demonstrated that AR-mediated paracrine signaling, particularly TGFβ signaling, from DP cells leads to the apoptosis of microvascular endothelial cells in the DP of balding scalp. These findings suggest that the regression of blood vessels in the DP, mediated by AR, plays a role in AGA and support the idea that early anti-AR treatment is more effective than late treatment.