Hair follicle stem cells promote epidermal regeneration under expanded condition

Abstract

Skin soft tissue expansion is the process of obtaining excess skin mixed with skin development, wound healing, and mechanical stretching. Previous studies have reported that tissue expansion significantly induces epidermal proliferation throughout the skin. However, the mechanisms underlying epidermal regeneration during skin soft tissue expansion are yet to be clarified. Hair follicle stem cells (HFSCs) have been recognized as a promising approach for epidermal regeneration. This study examines HFSC-related epidermal regeneration mechanisms under expanded condition and proposes a potential method for its cellular and molecular regulation.

Keywords: epidermal regeneration; hair follicle stem cells; mechanical stretch; skin soft tissue expansion; wound healing.

FIGURE 1

The effects of mechanical stretch on HFSCs and their niches Diverse groups of cells and extracellular matrix proteins around the HFSCs are organized to form a niche that serves to promote and maintain the optimal functioning of these stem cell populations. The hair cycle and HFSCs activation condition are changed induced by mechanical stretch. Under certain circumstances, HFSCs are transformed into epidermal stem cells which can be promoted by several growth factors secreted by M2 macrophages. These effects on HFSCs play important roles in epidermal regeneration.

FIGURE 2

Signaling pathways induced by HFSCs under mechanical stretching There are mainly three signaling pathways induced by HFSCs under mechanical stretching including Wnt/β-catenin, Shh and Notch pathway. They are underlying mechanisms of HFSCs promoting epidermal regeneration.