title: A plant oil-containing pH 4 emulsion improves epidermal barrier structure and enhances ceramide levels in aged skin.
abstract: OBJECTIVE
  Xerosis is a serious problem among the very old. It is a dermatological challenge caused by significant alterations in stratum corneum (SC) function and structure. Two negative changes in aged skin are (i) the enhanced skin surface pH and (ii) the altered SC lipid content, composition and ordering.
  
  
  METHODS
  Therefore, we investigated the way in which an acidic skin care product with different plant oils affects SC function, structure and lipid profile in older subjects with dry skin. Before and after a 3-week application period, different biophysical measurements were performed: transepidermal water loss, SC hydration and skin surface pH. In addition, the SC lipid matrix was evaluated by analysis of the intercellular lipid lamellae and the SC lipid profile.
  
  
  RESULTS
  After treatment, a significant increase in lipid lamellae in the intercellular space of the SC was observed in the area treated with the test product compared to the untreated area. Furthermore, the ceramide level was found to be increased, although ceramides were not provided by the acidic test formulation.
  
  
  CONCLUSIONS
  In summary, topical application of a pH 4.0 product containing plant oils improves epidermal barrier formation and SC lipid ordering and ratio in aged dry skin.
authors.affiliation: Research and Development, Kneipp GmbH, D-97084 Würzburg, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Blaak
authors.affiliation: Microscopy Services Dähnhardt GmbH, D-24220 Flintbek, Germany.
authors.forename: D
authors.initials: D
authors.lastname: Dähnhardt
authors.affiliation: Microscopy Services Dähnhardt GmbH, D-24220 Flintbek, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Dähnhardt-Pfeiffer
authors.affiliation: proDERM Institut für Angewandte Dermatologische Forschung GmbH, D-22869 Schenefeld, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Bielfeldt
authors.affiliation: proDERM Institut für Angewandte Dermatologische Forschung GmbH, D-22869 Schenefeld, Germany.
authors.forename: K-P
authors.initials: KP
authors.lastname: Wilhelm
authors.affiliation: Research and Development, Kneipp GmbH, D-97084 Würzburg, Germany.
authors.forename: R
authors.initials: R
authors.lastname: Wohlfart
authors.affiliation: Research and Development, Kneipp GmbH, D-97084 Würzburg, Germany.
authors.forename: P
authors.initials: P
authors.lastname: Staib
mesh_terms: D002518:Ceramides / Q000378:metabolism*; D004655:Emulsions; D006801:Humans; D006863:Hydrogen-Ion Concentration; D046529:Microscopy, Electron, Transmission; D010938:Plant Oils / Q000008:administration & dosage* / Q000737:chemistry; D012867:Skin / Q000378:metabolism*; D015595:Skin Aging
chemical_list: D002518:Ceramides; D004655:Emulsions; D010938:Plant Oils
keywords: ceramides; epidermal barrier; skin ageing; skin care; stratum corneum