Abstract: The article was a preliminary study of the effect of biochanin A on hair growth as well as its potential mechanisms.The testosterone-induced C57BL/6 alopecia mice were used as the pathology alopecia model.Four groups of treatment were tested including a blank control group,an alopecia model group,a biochanin A group and a minoxidil group.The model was constructed by measuring the differences of hair weight and length,the number of hair follicles between the blank control group and the alopecia model group.The effect of testosterone on hormones level was evaluated by comparing the difference of the hormone contents between blank control group and alopecia model group.The effect of biochanin A on hair growth and hormone level was assessed by comparing the differences of hair weight and length,the number of hair follicles and the hormone contents between alopecia model group and biochanin A group.The 5α-reductase inhibitory activity of biochanin A was analyzed using an in vitro micro-reaction system.The results showed that there was a significant difference between alopecia model group and blank control,as well as between alopecia model and biochanin A groups in terms of hair length,hair height,the number of hair follicles and androgen level.Also,biochanin A demonstrated positive 5α-reductase inhibitory activity.The concentration leading to 50% inhibitory rate (IC₅₀) was 94.45±6.92 μmol/L.The testosteroneinduced alopecia model was successfully constructed.Biochanin A showed a positive effect on the hair growth of testosterone-induced alopecia mice.The mechanism was possibly associated with the conversion of testosterone into lower activity products or inhibition of 5α-reductase.

Key words: biochanin A, testosterone, alopecia mice model, hair growth, 5&alpha, -reductase