Platelet-rich plasma-derived exosomes stimulate hair follicle growth through activation of the Wnt/β-Catenin signaling pathway.

Background: Androgenetic alopecia (AGA) is a common type of hair loss that affects a large segment of the global population, significantly influencing individuals' appearance and mental health. Existing treatments like minoxidil and finasteride have limited effectiveness and can cause side effects, highlighting the need for alternative therapies. Objective: This study aims to explore the effectiveness of platelet-rich plasma-derived exosomes (PRP-Exos) in stimulating hair follicle growth and the proliferation of human dermal papilla cells (DPCs), as well as to investigate the mechanisms involved. Methods: PRP-Exos were isolated and characterized using techniques such as nanoparticle tracking analysis (NTA), transmission electron microscopy (TEM), and Western blotting. The impact of PRP-Exos on DPC proliferation was measured using CCK-8 assays, while their migration was assessed through Transwell migration and scratch wound healing assays. Flow cytometry was used to analyze cell cycle progression. Hair follicle organ culture was employed to examine the effects of PRP-Exos on hair follicle growth, and in vivo experiments were conducted in a mouse model to assess the influence of PRP-Exos on hair follicles. Results: DPCs internalized PRP-Exos, which significantly boosted their proliferation and migration, as shown by CCK-8, Transwell migration, and scratch wound healing assays. Flow cytometry revealed that PRP-Exos facilitated cell cycle progression in DPCs. Furthermore, treatment with PRP-Exos resulted in increased levels of β-Catenin and Lef-1, along with decreased expression of SFRP1, indicating activation of the Wnt/β-Catenin pathway. Hair follicle organ culture indicated enhanced hair follicle growth and a prolonged anagen phase, delaying the transition to the telogen phase. In vivo studies demonstrated increased skin thickness, hair follicle diameter, and a favorable anagen-to-telogen ratio in mice, promoting hair growth during the telogen phase. Conclusions: PRP-Exos show promise as a therapeutic option for AGA by stimulating hair follicle growth through the activation of the Wnt/β-Catenin signaling pathway. These findings suggest that PRP-Exos could enhance hair follicle regeneration both in vitro and in vivo.