Hair Dermal papilla maintain its hair inducing characteristics via autocrine exosomal miR-23a-3p

ABSTRACT Human dermal papilla cells (hDPCs) are specialized mesenchymal cells that regulate hair follicle development and drive the hair cycle. However, when cultured in vitro, hDPCs progressively lose their hair-inductive capacity. This decline may be closely associated with the absence of the native microenvironmental niche, which plays a critical role in maintaining hDPC identity and function in vivo. In addition to extrinsic cues, autocrine signaling within the dermal papilla itself may serve as a key mechanism for sustaining its regenerative potential. In this study, we present a novel growth model that enables real-time tracking of hDPC functional recovery, with particular attention to autocrine signaling and niche reprogramming. Our results reveal that intrinsic feedback loops are essential for maintaining hDPC function during the anagen phase. By elucidating the dynamic interplay between hDPC expansion and hair-inductive capacity, this work advances our understanding of hair follicle biology and highlights new avenues for developing regenerative therapies for hair loss.