A neuroendocrinological perspective on human hair follicle pigmentation


  • Ralf Paus

    1. Department of Dermatology, University of Lübeck, Lübeck, Germany
    2. School of Translational Medicine, University of Manchester, Manchester, UK
    Search for more papers by this author

  • This essay is based on an lecture presented at the XVth PASPR Meeting in Memphis, TN, September 2009. It is dedicated with lasting gratitude to my friend and teacher in hair biology, Kurt S. Stenn, who always tried to stay as far away as possible from both pigmentation and neurohormones.

R. Paus, e-mail: ralf.paus@uk-sh.de


The role of neurohormones and neuropeptides in human hair follicle (HF) pigmentation extends far beyond the control of melanin synthesis by α-MSH and ACTH and includes melanoblast differentiation, reactive oxygen species scavenging, maintenance of HF immune privilege, and remodeling of the HF pigmentary unit (HFPU). It is now clear that human HFs are not only a target of multiple neuromediators, but also are a major non-classical production site for neurohormones such as CRH, proopiomelanocortin, ACTH, α-MSH, ß-endorphin, TRH, and melatonin. Moreover, human HFs have established a functional peripheral equivalent of the hypothalamic–pituitary–adrenal axis. By charting the author’s own meanderings through the jungle of hair pigmentation research, the current perspectives essay utilizes four clinical observations – hair repigmentation, canities, poliosis, and ‘overnight greying’– as points of entry into the enigmas and challenges of .pigmentary HF neuroendocrinology. After synthesizing key principles and defining major open questions in the field, selected research avenues are delineated that appear clinically most promising. In this context, novel neuroendocrinological strategies to retard or reverse greying and to reduce damage to the HFPU are discussed.