It is widely accepted that the occurrence of androgenetic alopecia (AGA) is closely related to androgen,androgen receptor and androgen-metabolizing enzymes.However,how they work in AGA remains unclear.Recent studies have shown that androgen exerts their roles by regulating various cytokines secreted by dermal papilla cells.At present,it is considered that insulin-like growth factor,vascular endothelial growth factor,transforming growth factor-β and Wnt inhibitory factor-1 are the most important and well-studied cytokines in the pathogenesis of AA,which may modulate hair growth via accelerating or deccelarating the growth of hair follicles.