ANTIOXIDANT ENZYME LEVELS IN RHEUMATOID ARTHRITIS

C. Kacar, O. Elmas , E. Gilgil , S. Urhan , T. Tuncer , Y. Aliciguzel , B. Butun Department of PM and R and Rheumatology, Department of Biochemistry, Akdeniz University Faculty of Medicine, Antalya, TurkeyObjectives: To measure the activities of antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), glutathione-S-transferase (GST) and malondialdehyde (MDA) as a marker of lipid peroxidation in erythrocytes of patients with rheumatoid arthritis (RA).Methods: Twenty two subjects who satisfied ACR criteria for RA, and 12 age and sex matched healthy controls were enrolled in this study.Activities of enzymes in the erythrocytes were determined using the following methods: SOD activity by the indirect inhibition technique of Misra and Fridovich, CAT activity by the method of Aebi, GSH-Px activity by the coupled assay of Paglia and Valentine, GST activity according to the procedure of Cohen et al.All enzymatic activities were expressed per gram of hemoglobin (Hb) at either 30.8°C (SOD, CAT and GST) or 37.8°C (GSH-Px). The results for CAT activities were expressed as the rate constant (k) of a first order reaction per gram of Hb.The lipid peroxidation contents of erythrocytes were determined by MDA production and assayed as thiobarbituric acid-reactive substances using the method of Stocks and Dormandy and the results were expressed as nmol/gHb using 1,1,3,3-tetraethoxypropane as standard.Hb content was determined by using the cyanmethemoglobin method.Results: Erythrocyte CAT, SOD and GST activities were significantly higher in the patients with RA (Table 1). There was no correlation between those enzymes and serum Hb level. Antioxidant enzyme levels in the patients with RA Patients Controls p Age (year) 52.00 ± 8.83 52.33 ±9.74 0.92 CAT (k/gHb) 231.27 ± 43.55 201.58 ± 30.11 0.04 SOD (U/gHb) 1474.73 ± 552.2 1039.34 ± 288.62 0.01 GSH-Px (U/gHb) 10.87 ± 4.35 10.49 ± 4.79 0.81 GST (U/gHb) 1.79 ± 0.29 1.39 ± 0.21 0.00 MDA (nmol/gHb) 0.24± 0.06 0.2 ± 0.05 0.12 ld]Conclusion: In conclusion, erythrocyte CAT, SOD, and GST activity were significantly higher in RA patients than controls. Further studies are required to determine the association between activities of those enzymes in erythrocytes and erythrocyte life time and/or anemia in chronic disease.Citation: , volume , supplement , year 2004, page Session: Rheumatoid arthritis – Etiology and pathogenesis/Animal models