title: Effects of alpha-hydroxy acids on photoaged skin: a pilot clinical, histologic, and ultrastructural study.
abstract: BACKGROUND
  alpha-Hydroxy acids (AHAs) have been reported to improve aging skin. The mechanisms of action of AHAs on epidermal and dermal compartments need clarification.
  
  
  OBJECTIVE
  Our purpose was to determine the effects of AHAs on photoaged human skin by clinical and microanalytic means.
  
  
  METHODS
  Patients applied a lotion containing 25% glycolic, lactic, or citric acid to one forearm and a placebo lotion to the opposite forearm for an average of 6 months. Thickness of forearm skin was measured throughout the study. Biopsy specimens from both forearms were processed for analysis at the end of the study.
  
  
  RESULTS
  Treatment with AHAs caused an approximate 25% increase in skin thickness. The epidermis was thicker and papillary dermal changes included increased thickness, increased acid mucopolysaccharides, improved quality of elastic fibers, and increased density of collagen. No inflammation was evident.
  
  
  CONCLUSIONS
  Treatment with AHAs produced significant reversal of epidermal and dermal markers of photoaging.
authors.affiliation: Department of Dermatology, Hahnemann University School of Medicine, Philadelphia, Pennsylvania, USA.
authors.forename: C M
authors.initials: CM
authors.lastname: Ditre
authors.forename: T D
authors.initials: TD
authors.lastname: Griffin
authors.forename: G F
authors.initials: GF
authors.lastname: Murphy
authors.forename: H
authors.initials: H
authors.lastname: Sueki
authors.forename: B
authors.initials: B
authors.lastname: Telegan
authors.forename: W C
authors.initials: WC
authors.lastname: Johnson
authors.forename: R J
authors.initials: RJ
authors.lastname: Yu
authors.forename: E J
authors.initials: EJ
authors.lastname: Van Scott
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001706:Biopsy; D002951:Citrates / Q000627:therapeutic use; D019343:Citric Acid; D003094:Collagen / Q000187:drug effects; D004547:Elastic Tissue / Q000187:drug effects / Q000473:pathology; D004817:Epidermis / Q000187:drug effects / Q000473:pathology / Q000648:ultrastructure; D005260:Female; D005542:Forearm; D006016:Glycolates / Q000627:therapeutic use; D006025:Glycosaminoglycans / Q000032:analysis; D006801:Humans; D006880:Hydroxy Acids / Q000627:therapeutic use*; D007773:Lactates / Q000627:therapeutic use; D019344:Lactic Acid; D008297:Male; D008543:Melanins / Q000032:analysis; D008854:Microscopy, Electron; D008875:Middle Aged; D010865:Pilot Projects; D010919:Placebos; D012867:Skin / Q000187:drug effects* / Q000473:pathology / Q000648:ultrastructure; D015595:Skin Aging / Q000187:drug effects*
chemical_list: D002951:Citrates; D006016:Glycolates; D006025:Glycosaminoglycans; D006880:Hydroxy Acids; D007773:Lactates; D008543:Melanins; D010919:Placebos; C031149:glycolic acid; D019343:Citric Acid; D019344:Lactic Acid; D003094:Collagen