Effect of caffeine and testosterone on the proliferation of human hair follicles in vitro

Int J Dermatol. 2007 Jan;46(1):27-35. doi: 10.1111/j.1365-4632.2007.03119.x.

Abstract

Background: Androgenetic alopecia (AGA) is a common problem in men of all ages, affecting approximately 50% at 50 years of age. The underlying cause is an androgen-dependent miniaturization of genetically predetermined hair follicles. Here, the hair organ culture model was used to investigate the effects of testosterone and caffeine; the latter being a promising candidate for hair growth stimulation.

Methods: Hair follicles from 14 biopsies, taken from the vertex areas from male AGA patients, were cultivated for 120-192 h in vitro with normal William's E medium (control) or William's E medium containing different concentrations of testosterone and/or caffeine. Hair shaft elongation was measured daily and at the end of cultivation, cryosections of follicles were stained with Ki-67 to evaluate the degree and localization of keratinocyte proliferation.

Results: Significant growth suppression was found in hair follicles treated with 5 microg/ml testosterone. This was counteracted by caffeine in concentrations of 0.001% and 0.005%. Moreover, caffeine alone led to a significant stimulation of hair follicle growth. These results were confirmed immunohistochemically by Ki-67 staining.

Conclusions: Androgen-dependent growth inhibition of ex vivo hair follicles from patients suffering from AGA was present in the human hair organ culture model, a constellation which may serve for future studies to screen new substances against androgen-dependent hair loss. Caffeine was identified as a stimulator of human hair growth in vitro; a fact which may have important clinical impact in the management of AGA.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Alopecia / metabolism
  • Alopecia / pathology*
  • Androgens / pharmacology*
  • Biopsy
  • Caffeine / pharmacology*
  • Hair Follicle / drug effects*
  • Hair Follicle / growth & development
  • Humans
  • Immunohistochemistry
  • In Vitro Techniques
  • Ki-67 Antigen / metabolism
  • Male
  • Middle Aged
  • Phosphodiesterase Inhibitors / pharmacology*
  • Scalp / pathology
  • Testosterone / pharmacology*

Substances

  • Androgens
  • Ki-67 Antigen
  • Phosphodiesterase Inhibitors
  • Caffeine
  • Testosterone