IL-6 inhibition improves nitric oxide in rheumatoid arthritis

Jaspreet Kaur, Ashit Syngle, Pawan Krishan, Kanchan Vohra, Nidhi Garg, Ladbans Kaur, Monica Chhabra
DOI: 10.15305/ijrci/v2i1/78



To investigate the serum nitrite levels in patients with active rheumatoid arthritis (RA) after treatment with tocilizumab, an IL-6 antagonist, and to correlate between inflammatory disease activity measures and endothelial dysfunction.

Materials and methods

Eleven anti-IL-6-naive RA patients with high disease activity (DAS28 >5.1) were investigated. Inflammatory disease activity (DAS28 and HAQ-DI scores, ESR and CRP), serum nitrite concentration and flow mediated dilation (FMD) of the brachial artery were measured before and after 12 weeks of therapy with tocilizumab 8mg/kg intravenous infusion every 4 weeks. Serum nitrite levels and FMD were also estimated in 10 age- and sex- matched healthy controls.


Serum nitrite levels in RA patients at baseline were significantly higher when compared to healthy volunteers (P <0.01). Level of serum nitrite significantly decreased (P <0.001), inflammatory disease activity measures and FMD significantly improved (P <0.001) after treatment. There was a significant correlation of serum nitrite with FMD, CRP, and DAS 28 both at baseline (P <0.05) and after 12 weeks therapy (P <0.05).


Nitrite production is enhanced to a greater extent in patients with RA compared to controls. Reduction in nitrite level after treatment is associated with the improvement in disease activity and endothelial dysfunction. Serum nitrite level may serve as a good predictor of both inflammatory disease activity and response to therapy in RA.



Kaur J, Syngle A, Krishan P, Vohra K, Garg N, Kaur L, Chhabra M. IJRCI. 2014;2(1):OA2 (27 May 2014) DOI: 10.15305/ijrci/v2i1/78


Serum nitrite; Endothelial dysfunction; Rheumatoid Arthritis; Tocilizumab, IL-6 antagonist.


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