Nature-derived lignan compound VB-1 exerts hair growth-promoting effects by augmenting Wnt/β-catenin signaling in human dermal papilla cells

Background, Vitexin is a kind of lignan compound which has been shown to possess a variety of pharmacological effects, such as anti-inflammatory, anti-oxidative and anti-cancer activities. However the effect of vitexin on hair regeneration has not been elaborated. Methods. The proliferation of human dermal papilla cells (hDPCs) was examined by cell counting and continuous cell culture after vitexin compound 1 (VB-1) was treated. The expression of lefl, wnt5a,bmp2,bmp4, alpl and vcan was examined by RT-PCR. The expression of dkk1, tgf-beta 1, active-beta-Catenin, and AXIN2 was examined by RT-PCR or immunoblotting, Hair shaft growth was measured the absence or presence of VB-1. Results. We demonstrated that VB-1 significantly promotes the proliferation of hDPCs in a concentration-dependent manner within a certain concentration range. Among the hair growth-related genes investigated, dkk1 was clearly down-regulated in hDPCs treated with VB-1, The increased active B-Catenin and decreased AXIN2 protein levels suggest that VB-1 facilitates Wnt/beta-catenin signaling in hDPCs in vitro. The expression of DP signature genes was also upregulated after VB-1 treatment. Our study further indicated that VB-1 promotes human hair follicle (HF) growth by HF organ culture' assay. Discussion. VB-1 may exert hair growth-promoting effects via augmenting Wnt/beta-catenin signaling in hDPCs.