title: Oxidative stress in keratoconus?
abstract: OBJECTIVE
  The purpose of this study was to establish the alterations of oxidative stress-related markers in keratoconus (KC) corneas.
  
  
  METHODS
  A total of 6 healthy and 11 ectatic corneas (7 KC and 4 post-LASIK) were studied. Different oxidative stress-related markers were determined to assess their implication in the KC pathophysiology. Total antioxidant capacity and total nitrites present in the samples were assayed. Furthermore, lipid peroxidation products and the glutathione contents were determined, together with 4-hydroxynonenal (4-HNE) immunohistochemistry, to establish the relationship between KC and oxidative stress.
  
  
  RESULTS
  The antioxidant capacity and glutathione content in KC corneas were decreased significantly when compared with healthy corneas. Moreover, the total nitrites and lipid peroxidation were significantly elevated in the corneas with KC when compared with the controls. There was a statistically significant difference in the amount of HNE-positive cells in KC corneas when compared with healthy corneas by immunohistochemistry. Post-LASIK ectatic corneas and KC corneas showed similar results.
  
  
  CONCLUSIONS
  The increased levels of oxidative stress markers and the decreased antioxidant capacity and antioxidant defenses in KC corneas, as well as in the post-LASIK ectatic corneas, indicate that oxidative stress might be involved in the development of this disease and may provide new insights for its prevention and treatment in the future.
authors.affiliation: Fundación Oftalmológica del Mediterráneo, Valencia, Spain.
authors.forename: Emma
authors.initials: E
authors.lastname: Arnal
authors.forename: Cristina
authors.initials: C
authors.lastname: Peris-Martínez
authors.forename: Jose Luis
authors.initials: JL
authors.lastname: Menezo
authors.forename: Siv
authors.initials: S
authors.lastname: Johnsen-Soriano
authors.forename: Francisco Javier
authors.initials: FJ
authors.lastname: Romero
mesh_terms: D000328:Adult; D000447:Aldehydes / Q000378:metabolism; D000975:Antioxidants / Q000378:metabolism*; D015415:Biomarkers / Q000378:metabolism; D004108:Dilatation, Pathologic / Q000378:metabolism / Q000503:physiopathology; D005260:Female; D005978:Glutathione / Q000378:metabolism; D006801:Humans; D007640:Keratoconus / Q000378:metabolism* / Q000503:physiopathology* / Q000601:surgery; D020731:Keratomileusis, Laser In Situ; D015227:Lipid Peroxidation / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D009573:Nitrites / Q000378:metabolism; D018384:Oxidative Stress / Q000502:physiology*
chemical_list: D000447:Aldehydes; D000975:Antioxidants; D015415:Biomarkers; D009573:Nitrites; D005978:Glutathione; C027576:4-hydroxy-2-nonenal