Upregulation of StAR and 3β-HSD in the bald scalp of Androgenetic Alopecia patients may simply reflect marked hyperplasia of sebaceous glands contrasted with the miniaturized hair follicles or imply the active de novo biosynthesis of androgens in pilosebaceous units. Given the juxtaposition of hair follicle and sebaceous glands, a kind of paracrine effect originating from sebaceous gland-secreted androgens on the growth and development of hair follicles is possible. Separate isolation of sebaceous glands and hair follicles to determine the difference of gene expression in bald and hairy scalp would help clarify the contributory role of each steroidogenic organ.
