Is there a relationship between serum ox-LDL, oxidative stress, and PON1 in knee osteoarthritis?

Previous in vitro studies have shown that oxidized low-density lipoprotein (ox-LDL) plays a role in the pathogenesis of osteoarthritis (OA). Paraoxonase-1 (PON1) protects both low-density lipoproteins (LDLs) and high-density lipoprotein (HDLs) against oxidative damage from circulating cells. In addition, PON1 is inactivated by ox-LDL and preserved by antioxidants. However, the relationship between serum ox-LDL, oxidative stress, and PON1 in knee OA remains unclear. Therefore, we investigated ox-LDL association with oxidative stress and PON1 in knee OA, and evaluated their relationships using radiological and clinical parameters. This study included 203 patients and 194 controls. The severity of OA was classified based on the Kellgren–Lawrence scoring system. In addition, each patient was clinically evaluated using the Western Ontario and McMaster University Osteoarthritis Index (WOMAC) score. Plasma concentrations of ox-LDL, oxidative stress markers, and PON1 were measured. Serum ox-LDL and oxidant parameters were significantly higher in patients compared to controls ( p