title: The role of neuropeptides in the multifactorial pathogenesis of acne vulgaris.
abstract: BACKGROUND
  Central or peripheral stress may induce the development of clinical inflammation in the pilosebaceous unit (PSU) leading to the development or to exacerbation of preexisting acne. The presence of a complete corticotropin-releasing hormone (CRH) system has been confirmed in human sebocytes in vitro. CRH is capable to induce lipid synthesis, steroidogenesis and interact with testosterone and growth hormone. alpha-Melanocyte-stimulating hormone (alpha-MSH) and its receptors can regulate melanogenesis as well as affect inflammation, apoptosis and sebogenesis.
  
  
  OBJECTIVE
  The purpose of the study was to investigate by immunohistochemistry if changes of CRH/CRH-binding protein (CRHBP)/CRH receptors (CRHR) as well as melanocortin-1 receptor (MC-1R) expression are detectable in acne lesions vs. normal skin, especially in the sebaceous gland (SG).
  
  
  RESULTS
  Very strong expression of CRH was observed in acne-involved skin in SG cells comparing with weaker expression in non-involved and normal skin SG. The strongest reaction for CRHBP in acne-involved SG was in differentiating sebocytes. CRHR-1 and -2 exhibited the strongest expression in sweat glands and SG, respectively. Sebocytes and cells of the ductus seboglandularis (DSG) of acne-involved and non-involved skin showed very intense MC-1R expression in contrast to less intense scattered immunoreactivity in normal skin samples.
  
  
  METHODS
  33 patients with acne vulgaris and 8 age-matched volunteers without acne participated in the study. Skin biopsies were taken from acne-involved face, the non-involved thigh skin of the same patients and from normal human skin.
  
  
  CONCLUSIONS
  These data suggest that NP, such as the complete CRH system and MC-1R, are involved in the pathogenesis of acne.
authors.forename: Ruta
authors.initials: R
authors.lastname: Ganceviciene
authors.forename: Markus
authors.initials: M
authors.lastname: Böhm
authors.forename: Sabine
authors.initials: S
authors.lastname: Fimmel
authors.forename: Christos C
authors.initials: CC
authors.lastname: Zouboulis