Decorin promotes proliferation and migration of ORS keratinocytes and maintains hair anagen in mice

DECORIN is a prototypical member of the small leucine‐rich proteoglycan (SLRP) family that plays important roles in numerous biological processes and cellular biological pathways. We previously showed that Decorin expression was highly enhanced in mouse dorsal hair follicles (HFs) during the anagen phase and was reduced during the catagen and telogen phases, suggesting that Decorin might modulate follicular cycling and morphogenesis. In this study, to further clarify the effects of DECORIN on hair cells and the cycling transition, an in vitro overexpression strategy and Decorin‐null (Dcn−/−) mice were used to investigate the effects of DECORIN on outer root sheath (ORS) keratinocytes. DECORIN overexpression significantly enhanced proliferation and migration in ORS keratinocytes in vitro. Moreover, DECORIN overexpression upregulated the mRNA and protein expression levels of WNT10b, β‐CATENIN and LEF1. The DECORIN overexpression‐induced increase in the proliferation and migration of ORS keratinocytes was partially inhibited by a Wnt/β‐catenin inhibitor. Furthermore, Dcn−/− mice had a shortened anagen phase and lower levels of β‐catenin expression than were observed in wild‐type mice in imaging and histological analyses. Taken together, these findings suggest that DECORIN promotes the proliferation and migration of ORS keratinocytes in vitro and maintains hair anagen in mice.