| Aim of the work: Considering the importance of toll-like receptor (TLR) 4 and oxidative stress in the
pathogenesis of autoimmune disorders, present study was designed to assess serum TLR4, 8-hydroxy-
20-deoxyguanosine (8-OHdG) as a marker of oxidative DNA damage, and total antioxidant capacity
(TAC) in rheumatoid arthritis (RA) patients and to study their relation with disease activity and their predictive
potential.
Patients and methods: 44 RA patients and 44 matched controls were studied. Disease activity score (DAS-
28) was assessed. Serum TLR4, 8-OHdG and TAC were measured.
Results: The mean age of patients was 44 ± 10.4 years, 33 females and 11 males with and disease duration
5.5 ± 3.8 months. The mean DAS-28 was 4.6 ± 0.6 (3.45–6.01). Rheumatoid factor (RF) and anti-cyclic
citrullinated peptide (anti-CCP) were both positive in 20 patients. Compared to control, the mean ± SD
of serum TLR4 (2.41 ± 4.50 vs. 1.20 ± 1.67 ng/ml), and 8-OHdG (67.67 ± 20.57 vs. 45.34 ± 30.61 ng/ml)
were significantly higher in patients (p < 0.001); whilst serum TAC (1.3 ± 0.5 vs. 2.01 ± 0.55 mmol/L)
was significantly lower (p < 0.001). TLR4, 8-OHdG were significantly increased and TAC decreased in
patients with positive RF/anti-CCP compared to negative (p < 0.001, p = 0.005 and p = 0.036 respectively).
TLR4 was significantly higher in patients with higher DAS-28 (p = 0.003) and both significantly correlated
(p < 0.001). Areas under the ROC curve of TLR4 (0.87; 95%CI: 0.78–0.96) and 8-OHdG (0.88; 95%CI: 0.79–
0.97) were greater than that of TAC (0.19, 95%CI: 0.09–0.29) (p < 0.001).
Conclusion: The TLR4, 8-OHdG and TAC showed high predictive value in RA disease. TLR4 can be
remarked as a sensitive and specific marker for determining disease activity in RA. |