IGFBP‐rP1 is a potential therapeutic target in androgenic alopecia

Abstract The available interventions for androgenic alopecia (AGA), the most common type of hair loss worldwide, remain limited. The insulin growth factor (IGF) system may play an important role in the pathogenesis of AGA. However, the exact role of IGF binding protein‐related protein 1 (IGFBP‐rP1) in hair growth and AGA has not been reported. In this study, we first found periodic variation in IGFBP‐rP1 during the hair cycle transition in murine hair follicles (HFs). We further demonstrated that IGFBP‐rP1 levels were lower in the serum and scalp HFs of individuals with AGA than in those of healthy controls. Subsequently, we verified that IGFBP‐rP1 had no cytotoxicity to human outer root sheath cells (HORSCs) and that IGFBP‐rP1 reversed the inhibitory effects of DHT on the migration of HORSCs in vitro. Finally, a DHT‐induced AGA mouse model was created. The results revealed that the expression of IGFBP‐rP1 in murine HFs was downregulated after DHT treatment and that subcutaneous injection of IGFBP‐rP1 delayed catagen occurrence and prolonged the anagen phase of HFs in mice with DHT‐induced AGA. The present work shows that IGFBP‐rP1 is involved in hair cycle transition and exhibits great therapeutic potential for AGA.