Hair Growth Promotion Activity and Its Mechanism of Polygonum Multiflorum

The study from 2015 examined the effects of Polygonum multiflorum Radix (PMR) and its processed form (PMRP) on hair growth in C57BL/6J mice. It found that oral administration of PMR resulted in a complete (100%) hair covered skin ratio, while oral PMRP achieved a 48%-88% ratio. Topical application of PMRP also showed a high hair covered skin ratio of about 90%. The research suggested that the hair growth promotion from oral PMR was likely due to the upregulation of fibroblast growth factor (FGF-7), and the topical PMRP worked by stimulating Sonic Hedgehog (SHH) expression. The study indicated that PMR and PMRP could be effective for hair growth promotion, with PMR being more effective orally and PMRP topically. The study did not find a dose-effect relationship for hair length and hair covered ratio, but did for hair total melanin contents. Further research was recommended to understand the potential of PMR and PMRP in treating androgenetic alopecia (AGA).