title: Plasma total antioxidant capacity, lipid peroxidation, and erythrocyte antioxidant enzyme activities in patients with rheumatoid arthritis and osteoarthritis.
abstract: OBJECTIVE
  The metabolism of cells in inflammatory and noninflammatory arthritic joint diseases is subject to complex environmental controls. The aim of the present study was to investigate the total antioxidant capacity (TAC), levels of lipid peroxidation (LPO), and antioxidant enzyme activities in patients with rheumatoid arthritis (RA) and osteoarthritis (OA).
  
  
  METHODS
  Plasma levels of TAC, malondialdehyde (MDA), the activities of some erythrocyte antioxidant enzymes, as well as erythrocyte sedimentation rates (ESR) were estimated in patients with RA and OA and compared with controls.
  
  
  RESULTS
  The plasma TAC levels were significantly lower in the RA group than the OA and control group (P < 0.05). Plasma MDA concentrations were significantly higher in patients with RA than those with OA and healthy subjects (P < 0.05). Erythrocyte GSH-Px and CAT activities were found to be significantly lower in patients with RA than those with OA and healthy subjects (P < 0.05, P < 0.05, respectively). However, there were no significant differences in erythrocyte SOD activities between the groups (P > 0.05). ESR were significantly higher in RA patients than in healthy subjects and patients with OA (P < 0.01). Moreover, there were significant negative correlations between TAC vs. MDA, ESR vs. TAC, and a positive correlation between ESR vs. MDA in the RA group (r = -0.398, P < 0.05; r = -0.422, P < 0.05; r = 0.530, P < 0.05, respectively).
  
  
  CONCLUSIONS
  Our results demonstrated that levels of LPO are increased in patients with RA compared to patients with OA. In addition, plasma TAC levels are decreased in RA due to its inflammatory character. We conclude that detecting plasma TAC levels with this novel method may be used as a routine and rapid test to verify the levels of oxidative stress in RA. Furthermore, correlating TAC and LPO levels with acute phase reactants such as ESR may give some clues about disease activity in RA.
authors.affiliation: Department of Orthopaedic Surgery, Harran University, Medical Faculty, 63200 Sanliurfa, Turkey. sezginsarban@harran.edu.tr
authors.forename: Sezgin
authors.initials: S
authors.lastname: Sarban
authors.forename: Abdurrahim
authors.initials: A
authors.lastname: Kocyigit
authors.forename: Mithat
authors.initials: M
authors.lastname: Yazar
authors.forename: Ugur E
authors.initials: UE
authors.lastname: Isikan
mesh_terms: D000328:Adult; D000975:Antioxidants / Q000032:analysis*; D001172:Arthritis, Rheumatoid / Q000097:blood*; D001799:Blood Sedimentation; D002374:Catalase / Q000097:blood; D004912:Erythrocytes / Q000201:enzymology*; D005260:Female; D005979:Glutathione Peroxidase / Q000097:blood; D006801:Humans; D015227:Lipid Peroxidation / Q000502:physiology*; D008297:Male; D008315:Malondialdehyde / Q000097:blood; D008875:Middle Aged; D010003:Osteoarthritis / Q000097:blood*; D013482:Superoxide Dismutase / Q000097:blood
chemical_list: D000975:Antioxidants; D008315:Malondialdehyde; D002374:Catalase; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase