# Exosomes derived from mouse vibrissa dermal papilla cells promote hair follicle regeneration during wound healing by activating Wnt/β-catenin signaling pathway

## TL;DR

Exosomes from mouse dermal papilla cells help regenerate hair follicles during wound healing by activating a key signaling pathway.

## Contribution

This is the first study to analyze the effects of dermal papilla cell-derived exosomes on fibroblasts during wound healing.

## Key findings

- DPC-Exos stimulate fibroblast proliferation, migration, and hair-inducing capacity.
- DPC-Exos promote wound re-epithelialization and hair follicle regeneration in mice.
- Wnt/β-catenin signaling is activated by DPC-Exos and is essential for their effects.

## Abstract

Hair follicle (HF) regeneration during wound healing continues to present a significant clinical challenge. Dermal papilla cell-derived exosomes (DPC-Exos) hold immense potential for inducing HF neogenesis. However, the accurate role and underlying mechanisms of DPC-Exos in HF regeneration in wound healing remain to be fully explained. This study, represents the first analysis into the effects of DPC-Exos on fibroblasts during wound healing. Our findings demonstrated that DPC-Exos could stimulate the proliferation and migration of fibroblasts, more importantly, enhance the hair-inducing capacity of fibroblasts. Fibroblasts treated with DPC-Exos were capable of inducing HF neogenesis in nude mice when combined with neonatal mice epidermal cells. In addition, DPC-Exos accelerated wound re-epithelialization and promoted HF regeneration during the healing process. Treatment with DPC-Exos led to increased expression levels of the Wnt pathway transcription factors β-catenin and Lef1 in both fibroblasts and the dermis of skin wounds. Specifically, the application of a Wnt pathway inhibitor reduced the effects of DPC-Exos on fibroblasts and wound healing. Accordingly, these results offer evidence that DPC-Exos promote HF regeneration during wound healing by enhancing the hair-inducing capacity of fibroblasts and activating the Wnt/β-catenin signaling pathway. This suggests that DPC-Exos may represent a promising therapeutic strategy for achieving regenerative wound healing.