Nitric oxide and superoxide dismutase in juvenile connective tissue diseases

الملخص EN

Nitric oxide (NO) may be a critical mediator in the inflammatory cascade of rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE).

Superoxide anion (O2-) plays an important role in reactive oxygen species.

In order to explore their effects on the pathogenesis of these diseases, we measured serum nitrite and nitrate as end products of NO metabolites by using Griess reagent and spectrophotometric assay.

Also, the synovial fluid nitrite and nitrate were determined in patients with juvenile rheumatoid arthritis.

Superoxide dismutase (SOD) activity was measured with the spectrophotometer at 505 nm.

Serum nitrite and nitrate in juvenile SLE patients (16.88 ± 5.53 ∞ M / L and 72.5 ± 15.1 ∞ M / L respectively) were significantly higher than in healthy subjects (3.2 ± 1.3 ∞M / L, 23.1 ± 9.34 ∞ M / L respectively) p < 0.001.

Serum nitrite and nitrate in juvenile rheumatoid arthritis patients (5.66 ± 2.4 ∞ M / L, 39.1± 16.3 ∞ M / L respectively) were significantly higher than in healthy subjects p < 0.002, < 0.005 respectively.

Synovial fluid nitrite was significantly higher than serum nitrite in rheumatoid arthritis (7.7 ± 2.9∞ M / L vs 5.66 ± 2.4 ∞ M / L) p < 0.05.

The elevated serum nitrite correlated with disease activity indices as the articular index, morning stiffness, CRP, ESR and SLEDAI.

Our results also showed a significant decreased SOD activity in juvenile SLE (614.7 ± 98.4 U / g Hb), and juvenile RA (1075.9 ± 234.6 U / g Hb), than healthy subjects (1537.8 ± 327.3 U / g / Hb) p < 0.001.

We concluded that NO production increased in juvenile SLE and juvenile RA while the superoxide dismutase activity was reduced reflecting their role in the pathogenesis in those connective tissue diseases.