Baicalin increases hair follicle development by increasing canonical Wnt/β-catenin signaling and activating dermal papillar cells in mice

Baicalin is a traditional Chinese herbal medicine commonly used for hair loss, the precise molecular mechanism of which is unknown. In the present study, the mechanism of baicalin was investigated via the topical application of baicalin to reconstituted hair follicles on mice dorsa and evaluating the effect on canonical Wnt/β-catenin signaling in the hair follicles and the activity of dermal papillar cells. The results indicate that baicalin stimulates the expression of Wnt3a, Wnt5a, frizzled 7 and disheveled 2 whilst inhibiting the Axin/casein kinase 1α/adenomatous polyposis coli/glycogen synthase kinase 3β degradation complex, leading to accumulation of β-catenin and activation of Wnt/β-catenin signaling. In addition, baicalin was observed to increase the alkaline phosphatase levels in dermal papillar cells, a process which was dependent on Wnt pathway activation. Given its non-toxicity and ease of topical application, baicalin represents a promising treatment for alopecia and other forms of hair loss. Further studies of baicalin using human hair follicle transplants are warranted in preparation for future clinical use.