Abstract
Objective: Hydrogen sulfide (H2S) is a gaseous mediator produced in the body. In experimental models, endogenously produced H2S has been shown to have pro-inflammatory effects. The aim of this study was to investigate whether H2S is present in three common rheumatic diseases, rheumatoid arthritis (RA), gout and osteoarthritis (OA) and to determine if H2S levels correlate with disease activity.
Methods: Patients with RA, gout, OA, and healthy controls (n = 30 each) were recruited. Plasma and where possible, synovial fluid (SF), were obtained. Levels of H2S and interleukin-6 (IL-6) (a known inflammatory marker as a positive control) were determined and assessed for their relationship with disease activity.
Results: SF-H2S levels were significantly elevated in both RA and gout when compared to respective plasma levels. Plasma levels of H2S were not different from those in healthy controls in patients with either RA or gout. In OA, plasma levels of H2S were significantly elevated compared to healthy controls. In RA, SF-H2S levels correlated with Disease Activity Score (DAS)-28 and tender joint count.
Conclusion: H2S is present in the joint and acts as a pro-inflammatory mediator in rheumatic diseases. H2S may be a novel therapeutic target for these conditions.