Cartilaginous glycoprotein‑39 as laboratory marker of dynamics of course and effectiveness of treatment in patients with osteoarthritis

Abstract

Backgrounds. Osteoarthritis (OA) occupies the first rank among diseases of the musculoskeletal system and accounts for 18.4% of the structure of this pathology. Currently, OA is considered as a disease in which there is a violation of the processes of remodeling (degradation and synthesis) of cartilage tissues, subchondral bone, joint capsule, tendon-ligamentous and muscular apparatus. An increased concentration of cartilage glycoprotein-39 (CGP-39) in the circulation is associated with inflammatory diseases and the processes of active tissue restructuring. To date, CGP-39 is a marker of chondrocyte activation and a sign of progressive OA, which determines its clinical significance. Along with this, the role of this biomarker in evaluating the effectiveness of anti-inflammatory therapy is relevant.The purpose. Comparative assessment of the quantitative content of CGP-39 in patients with knee joint OA, depending on the severity of inflammatory changes in the joints, the dynamics of the disease and the effectiveness of therapy.Methods. The study included 36 patients with OA and 30 practically healthy volunteers, identical in gender and age to the examined patients. The mean age of patients was 64 years, the average duration of the disease was 6 years. The diagnosis was determined according to the diagnostic criteria of the American College of Rheumatology (ACR, 1991). Along with the generally accepted clinical, laboratory and instrumental diagnosis of OA, in all patients and in control persons the levels of circulating CGP-39 were measured by enzyme immunoassay (ELISA). All examined patients received Ambene® Bio for 20 days, followed by repeated determination of the level of CGP-39. For statistical processing of the obtained data, we have used the programs Microsoft Excel 2007 and Statistica 10.0. Using the application program KRelRisk 1.1, the relative risk indicator for the studied factor was determined.Results. In the blood of patients with OA, a significant increase in the levels of CGP-39 has been found in comparison with the group of healthy individuals, which indicates increased degradation of articular cartilage in OA. As the severity of knee OA increased, the concentration of CGP-39 in the blood serum significantly raised, including in comparison with the control group. Reliable direct correlations were found between CGP-39 and clinical indices of knee OA severity. The content of CGP-39 in serum in patients with stage III radiological OA was significantly higher than in patients with stage I–II. The highest level of CGP-39 in patients with OA is associated with the presence of synovitis. TThe level of CGP-39 significantly decreased in patients with knee OA after a course of Ambene® Bio therapy, which confirms the participation of CGP-39 in inflammation on the one hand and the possibility of its use as an indicator of the effectiveness of anti-inflammatory therapy on the other hand.Conclusions. CGP-39 as a marker of inflammation and degradation of articular cartilage reflects the severity of the course of OA. The investigation of this biomarker is useful not only for diagnostic purposes, but also to assess the response to anti-inflammatory treatment in patients with knee OA.