New effects of caffeine on corticotropin‐releasing hormone (CRH)‐induced stress along the intrafollicular classical hypothalamic–pituitary–adrenal (HPA) axis (CRH‐R1/2, IP ₃ ‐R, ACTH, MC‐R2) and the neurogenic non‐HPA axis (substance P, p75 ^NTR and TrkA) in ex vivo human male androgenetic scalp hair follicles

Abstract

Background Human hair is highly responsive to stress, and human scalp hair follicles (HFs) contain a peripheral neuroendocrine equivalent of the systemic hypothalamic-pituitary-adrenal (HPA) stress axis. Androgenetic alopecia (AGA) is supposed to be aggravated by stress. We used corticotropin-releasing hormone (CRH), which triggers the HPA axis, to induce a stress response in human ex vivo male AGA HFs. Caffeine is known to reverse testosterone-mediated hair growth inhibition in the same hair organ culture mod…