Endogenous Retinoids in the Pathogenesis of Alopecia Areata

The document discussed the role of endogenous retinoids in the pathogenesis of alopecia areata (AA), highlighting that retinoids, derivatives of vitamin A, significantly influenced hair follicle biology and immune regulation. Studies using human patients and rodent models found that increased retinoic acid (RA) synthesis enzymes and binding proteins were present in AA, with high dietary vitamin A accelerating AA onset and deficiency leading to more severe disease. The research suggested that precise vitamin A levels are crucial, as they alter immune factors and could make AA patients more sensitive to exogenous retinoids. The findings indicated that targeting retinoid pathways might offer new therapeutic strategies for managing AA by regulating both the hair cycle and immune response.