Qualitative and quantitative evaluation of plasma glycosaminoglycans (GAGs) of rheumatoid arthritis (RA) patients in relation to disease activity estimated by DAS28 score was evaluated.
GAGs were quantified by hexuronic acid assay and electrophoretic fractionation. Keratan sulfate (KS) and hyaluronic acid (HA) were measured by immunoassay.
Chondroitin/dermatan sulfate (CS/DS) and heparan sulfate/heparin (HS/H) in plasma of healthy subjects and RA patients were stated. Total GAGs, CS, HS/H and HA levels were higher in patients with high and moderate disease activity than in controls. Total GAGs and CS levels in patients with high disease activity were elevated in comparison to patients with low disease activity. HS/H levels in patients with high and moderate activity were elevated in comparison to those with low disease activity. KS levels were increased in all patient groups in comparison to controls. Total GAGs, CS, HS/H and HA levels were positively correlated with DAS28 and CRP.
Structural tissue damage/remodeling of the extracellular matrix occurs in RA, which is reflected in the qualitative and quantitative changes of plasma GAGs. The above changes depend on DAS28 and may contribute to systemic changes in the properties of the extracellular matrix.