title: Relationship between anti-CCP antibodies and oxidant and anti-oxidant activity in patients with rheumatoid arthritis.
abstract: OBJECTIVE
  A new group of autoantibodies in Rheumatoid Arthritis (RA), the anti-cyclic citrullinated peptide (anti-CCP) antibodies directed to citrulline-containing proteins, which are of value for the severity of RA. Up to date, the relationship between anti-CCP antibodies and oxidant, anti-oxidant activity in patients with RA has not been elucidated in the previous studies. In this study we aimed to investigate the effect of anti-CCP antibodies in the circulation on whole blood, serum and synovial fluid oxidant and anti-oxidant activity in patients with RA.
  
  
  METHODS
  RA patients with anti-CCP (+) (n=25) and anti-CCP (-) (n=24) were recruited into the study. All patients had a positive rheumatoid factor (RF). The patients who were under treatment with only non-steroidal antiinflammatory drugs (NSAID) at the study time included in the study. Catalase (CAT), Glutathione peroxidase (GSHPx), Myeloperoxidase (MPO) activities and the levels of Malondialdehyde (MDA) were measured in whole blood, serum and synovial fluid in both groups.
  
  
  RESULTS
  There were no significant differences in terms of the mean whole blood and serum antioxidative activity (CAT, GSHpx) and the mean blood and serum MDA and MPO values (oxidative activity), between the patients with anti-CCP(+) and those with anti-CCP(-). There was increased synovial oxidant activity (MDA and MPO levels) (p<0.05) in anti-CCP(+) RA patients with or without ESR negativity when compared with anti-CCP(-) RA patients. There was positive correlation between anti-CCP antibody levels and synovial MDA and MPO levels (r=0.435, p<0.05, r=0.563, p<0.05 respectively) in anti-CCP (+) group.
  
  
  CONCLUSIONS
  In conclusion, anti-CCP antibody positivity seems to be associated with increased synovial fluid oxidant activity (increased MDA and MPO levels) in patients with RA. These conclusions need to be validated in a larger controlled study population.
authors.affiliation: Yuzuncu Yil University, Medical Faculty, Department of Physical Medicine Rehabilitation and Rheumatology, Van, Turkey. leventediz@gmail.com
authors.forename: Levent
authors.initials: L
authors.lastname: Ediz
authors.forename: Ozcan
authors.initials: O
authors.lastname: Hiz
authors.forename: Halil
authors.initials: H
authors.lastname: Ozkol
authors.forename: Elif
authors.initials: E
authors.lastname: Gulcu
authors.forename: Murat
authors.initials: M
authors.lastname: Toprak
authors.forename: Mehmet Fethi
authors.initials: MF
authors.lastname: Ceylan
mesh_terms: D000328:Adult; D000906:Antibodies / Q000097:blood*; D000975:Antioxidants / Q000378:metabolism*; D001172:Arthritis, Rheumatoid / Q000276:immunology*; D002374:Catalase / Q000097:blood / Q000378:metabolism; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005979:Glutathione Peroxidase / Q000097:blood / Q000378:metabolism; D006801:Humans; D008297:Male; D008315:Malondialdehyde / Q000378:metabolism; D008875:Middle Aged; D010456:Peptides, Cyclic / Q000276:immunology*; D009195:Peroxidase / Q000097:blood / Q000378:metabolism
chemical_list: D000906:Antibodies; D000975:Antioxidants; D010456:Peptides, Cyclic; C487763:cyclic citrullinated peptide; D008315:Malondialdehyde; D002374:Catalase; D009195:Peroxidase; D005979:Glutathione Peroxidase