title: Increased in vivo collagen synthesis and in vitro cell proliferative effect of glycolic acid.
abstract: BACKGROUND
  Glycolic acid treatment is believed to reverse the photoaging process by increasing collagen synthesis in the skin. However, this effect has not been clearly defined even though alpha hydroxy acid products are used extensively.
  
  
  OBJECTIVE
  This study aimed to define the primary effect of glycolic acid on collagen synthesis that may be achieved by functional activation or proliferation of fibroblasts.
  
  
  METHODS
  Glycolic acid treatment was compared in vivo with lactic acid (hairless mice) and in vitro to malic acid (normal human skin fibroblast culture) with controls. To find the functional activation of fibroblasts, Northern blot assay for type I collagen synthesis with histometric analysis (in vivo) was performed. Cell proliferation assay (MTT) with procollagen type I C-peptide (PICP) enzyme immunoassay and radioisotope ([3H]proline) incorporated collagen production from cultured fibroblasts were determined.
  
  
  RESULTS
  The in vivo collagen mRNA expression with histometric analysis revealed greater collagen synthesis by glycolic acid compared with lactic acid and control. In vitro cell proliferative effect of glycolic and greater amount of collagen production showed a steady increase in a dose-dependent manner.
  
  
  CONCLUSIONS
  Both in vivo and in vitro, glycolic acid treatment increased the production of collagen and fibroblast proliferation. These effects may be the mechanism by which glycolic acid reverses the process of photoaging.
authors.affiliation: Department of Dermatology, Chonnam University Research Institute of Medical Science, Chonnam National University Medical School, Kwangju, Korea.
authors.forename: S J
authors.initials: SJ
authors.lastname: Kim
authors.forename: J H
authors.initials: JH
authors.lastname: Park
authors.forename: D H
authors.initials: DH
authors.lastname: Kim
authors.forename: Y H
authors.initials: YH
authors.lastname: Won
authors.forename: H I
authors.initials: HI
authors.lastname: Maibach
mesh_terms: D000818:Animals; D015152:Blotting, Northern; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured / Q000187:drug effects; D003094:Collagen / Q000096:biosynthesis / Q000187:drug effects*; D003879:Dermatologic Agents / Q000494:pharmacology*; D005347:Fibroblasts / Q000187:drug effects*; D006016:Glycolates / Q000494:pharmacology*; D006801:Humans; D019344:Lactic Acid / Q000494:pharmacology; D008293:Malates / Q000494:pharmacology; D008297:Male; D051379:Mice; D008812:Mice, Hairless; D012867:Skin / Q000187:drug effects*; D015595:Skin Aging / Q000187:drug effects*
chemical_list: D003879:Dermatologic Agents; D006016:Glycolates; D008293:Malates; C031149:glycolic acid; D019344:Lactic Acid; C030298:malic acid; D003094:Collagen