title: Oxidative stress impairs endothelial nitric oxide levels in Behçets' disease.
abstract: BACKGROUND
  Behçet's disease (BD) is an inflammatory vasculitis. Endogenous nitric oxide (NO), produced by endothelial cells, has pleiotropic effects such as vasodilatator, antiplatelet, antiproliferative. Reactive oxygen species (ROS) are produced at sites of endothelial inflammation. ROS target polyunsaturated lipids, which results in malondialdehyde (MDA) production.
  
  
  OBJECTIVE
  The aim was to investigate the oxidative stress in BD patients by measuring MDA and total antioxidant status (TAS) levels and to establish a possible relationship with respect to NO levels regarding disease activity.
  
  
  METHODS
  55 BD patients (30 active/25 inactive) and 20 healthy volunteers were included in the study. Blood samples were drawn following an overnight fasting. TAS and MDA levels were determined spectrophotometrically. Serum nitrite (NO(2-)) and nitrate (NO(3-)) levels were measured to estimate NO production. Data were expressed as mean ± SD.
  
  
  RESULTS
  TAS levels were significantly lower in BD patients than the controls (1.19 ± 0.34 vs. 3.29 ± 0.89 mmol/L). In the active BD group, MDA levels (0.36 ± 0.19 nmol/mL) were significantly higher than both the inactive BD group (0.25 ± 0.18 nmol/mL) and controls (0.18 ± 0.41 nmol/mL). NO levels were significantly lower in the active group compared to the inactive group (18.0 ± 2.80 vs. 19.40 ± 2.70 µmol/L). MDA levels correlated negatively with NO levels in the active group.
  
  
  CONCLUSIONS
  Decreased NO levels mediated by increased oxidative stress significantly contribute to endothelial dysfunction observed in BD.
authors.affiliation: Celal Bayar University School of Medicine, Department of Biochemistry, Manisa, Turkey. ece.onur@bayar.edu.tr
authors.forename: Ece
authors.initials: E
authors.lastname: Onur
authors.forename: Ceyda
authors.initials: C
authors.lastname: Kabaroglu
authors.forename: Isil
authors.initials: I
authors.lastname: Inanir
authors.forename: Ahmet
authors.initials: A
authors.lastname: Var
authors.forename: Yesim
authors.initials: Y
authors.lastname: Guvenc
authors.forename: Ozlem
authors.initials: O
authors.lastname: Gunay
authors.forename: Kamer
authors.initials: K
authors.lastname: Gunduz
mesh_terms: D000328:Adult; D000975:Antioxidants / Q000378:metabolism; D001528:Behcet Syndrome / Q000097:blood / Q000378:metabolism* / Q000503:physiopathology; D016022:Case-Control Studies; D004730:Endothelium, Vascular / Q000378:metabolism* / Q000503:physiopathology; D005260:Female; D006801:Humans; D015227:Lipid Peroxidation; D008297:Male; D008315:Malondialdehyde / Q000097:blood; D009566:Nitrates / Q000097:blood; D009569:Nitric Oxide / Q000378:metabolism*; D018384:Oxidative Stress
chemical_list: D000975:Antioxidants; D009566:Nitrates; D009569:Nitric Oxide; D008315:Malondialdehyde