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

Fischer, T. W. MD
Hipler, U. C. PhD
Elsner, P. 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. E-mail: [email protected]

International Journal of Dermatology 46(1):p 27-35, January 2007.

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.