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

  • T. W. Fischer, MD,
  • U. C. Hipler, PhD, and
  • P. Elsner, MD
  • From the Department of Dermatology and Allergology, Friedrich-Schiller-University, Jena, Germany, Department of Dermatology, University Hospital Schleswig-Holstein, University of Lübeck, Lübeck, Germany

Correspondence Tobias W. Fischer, MD Department of Dermatology and Allergology Friedrich-Schiller-University Jena Erfurter Str. 35 07740 Jena Germany


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 µg/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.