Combatting ageing in dermal papilla cells and promoting hair follicle regeneration using exosomes from human hair follicle dermal sheath cup cells

Abstract Dermal papilla cells (DPCs) undergo premature ageing in androgenetic alopecia and senescent alopecia. As critical components of hair follicle reconstruction, DPCs are also prone to senescence in vitro, resulting in a diminished hair follicle inductivity capacity. Dermal sheath cup cells (DSCCs), a specific subset of hair follicle mesenchymal stem cells, intimately linked to the function of DPCs. The primary objective of this research is to investigate the anti‐ageing effect of exosomes derived from DSCCs (Exo DSCCs ) on DPCs. Exosomes were utilized to treat H 2 O 2 ‐induced DPCs or long‐generation DPCs(P10). Our findings demonstrate that Exo DSCCs(P3) promote the proliferation, viability and migration of senescent DPCs while inhibiting cell apoptosis. The expression of senescence marker SA‐β‐Gal were significantly downregulated in senescent DPCs. When treated with Exo DSCCs(P3) , expression of inducibility related markers alkaline phosphatase and Versican were significantly upregulated. Additionally, Exo DSCCs(P3) activated the Wnt/β‐catenin signalling in vitro. In patch assay, Exo DSCCs(P3) significantly promoted hair follicle reconstruction in senescent DPCs. In summary, our work highlights that Exo DSCCs(P3) may restore the biological functions and improve the hair follicle induction ability of senescent DPCs. Therefore, Exo DSCCs(P3) may represent a new strategy for intervening in the ageing process of DPCs, contributing to the prevention of senile alopecia.