Proresorptive Activity of Cytokine System, Bone Turnover and Lipoperoxidation in the Pathogenesis of Early Knee Osteoarthrosis

Abstract Osteoarthrosis (ОА) is a condition that features inflammation and degeneration in the articular structures thus affecting the patients’ quality of life. This is a multifactor disease that involves various pathogenetic mechanisms with the imbalance of bone turnover being one of the basic; this results in the joint function impairment. There are studies proving the regulatory effect of cytokine system components on the cell functions in articular structures. Moreover, the enhancement of lipid peroxidation in a certain way contributes to the progressing of this pathology. Although these pathogenetic mechanisms have been thoroughly studied in severe clinical and radiological stages of OA, the perception of early X-ray negative presentations of articular pathologies remains controversial. The aim of this study was to investigate the role of proresorptive in cytokine system, bone turnover, and lipid peroxidation in the pathogenesis of early knee OA. We examined 51 patients (17 men and 34 women) with early knee OA. The control group was made up of 23 donors of both genders with no severe clinical symptoms or articular pathologies. All patients underwent ultrasound scanning, MRI and radiography of their knee joints. Bone turnover was assessed by the level of resorption (β-C-terminal telopeptides of type I collagen (β-CrossLaps)) and bone formation (bone alkaline phosphatase (BAP)) markers. Proresorptive cytokine activity was estimated by the content of tumor necrosis factor-alpha (TNF-α) and interleukin-1β (IL-1β). The intensity of lipid peroxidation was determined by the content of lipid hydroperoxides and malondialdehyde. Our findings showed that even in early stage of knee OA the patients feature the distress of their bone turnover manifested by an increased levels of both destructive (β-CrossLaps) and osteogenetic (BAP) markers along with an increase of pro-resorptive cytokine components (TNF-α and IL-1β) in serum and enhancement of lipid peroxidation. These data suggests that the identified changes in the markers characterizing bone turnover, lipid peroxidation and cytokine activity are promising in terms of objectifying the condition of patients with early knee OA as well as studying pathogenetic mechanisms and choosing therapeutic strategies for this pathology.