Abstract: Objective:To determine the effect of leptin on androgenetic alopecia. Methods: Forty male C57 mice were randomly assigned. Ten mice were not treated (blank group) and 30 mice were treated with 5 mg/kg·d testosterone propionate injection for 4 weeks to establish the androgenetic alopecia mouse model. Then the mice model were divided into three groups and treated for 4 weeks: model group (testosterone propionate injection), minoxidil group (testosterone propionate injection+topical 5% minoxidil tincture), leptin group (testosterone propionate+restructuring mice leptin). The ratio of the number of hair follicles in the growing period to the number of hair follicles in the resting period (A/T) was assessed. The proliferation and apoptosis and androgen receptor protein content in alopecia was detected. Results: (1) The area of hair loss in the minoxidil group and leptin group was smaller than that in the model group. (2) Compared to the model group, the A/T score and Ki67 level in the minoxidil group and leptin group were significantly higher (Ps<0.05), and there was no significant statistical difference between minoxidil group and leptin group (Ps> 0.05). (3) There were no statistically significant difference in apoptotic expression and AR receptor level between the minoxidil group and leptin group (Ps>0.05). Conclusion: Subcutaneous injection of leptin is effective on androgenetic alopecia mice model, and the effect is equivalent to topical 5% minoxidil solution. 

Key words: leptin, androgenetic alopecia, proliferation, apoptosis, androgen receptors