Association of serum Wnt1-inducible signaling pathway protein 1 (WISP1) levels with osteoarthritis and obesity-related inflammation in obese adults.

Osteoarthritis (OA) is increasingly recognized as a metabolically influenced inflammatory disease, particularly in the context of obesity. Wnt1-inducible signaling pathway protein 1 (WISP1), a downstream mediator of Wnt/β-catenin signaling, has been implicated in adipose tissue inflammation and cartilage remodeling; however, clinical data regarding circulating serum WISP1 levels in obesity-associated OA remain limited. This study aimed to investigate the relationship between serum WISP1 concentrations and OA status in obese adults. This cross-sectional study included 180 participants classified into three groups: healthy non-obese controls (n = 60), obese individuals without OA (n = 60), and obese individuals with OA (n = 60). Clinical, anthropometric, metabolic, and inflammatory parameters were recorded. Serum WISP1 concentrations were measured using enzyme-linked immunosorbent assay (ELISA). Group comparisons, correlation analyses, logistic regression models, and receiver operating characteristic (ROC) analyses were performed. Serum WISP1 concentrations differed significantly among groups, showing a stepwise increase from healthy controls to obese OA (-) and obese OA (+) participants (p < 0.001). WISP1 remained independently associated with osteoarthritis among obese individuals after adjustment for age, sex, body mass index, HOMA-IR, diuretic use and C-reactive protein (OR 1.003; 95% CI 1.001-1.005). Although obese participants demonstrated adverse metabolic and inflammatory profiles compared with controls, most metabolic parameters did not distinguish OA subgroups within obesity. ROC analysis demonstrated good discriminatory performance of WISP1 for distinguishing obese OA (+) from obese OA (-) groups (AUC 0.807, 95% CI 0.727-0.879, p < 0.001). Serum WISP1 concentrations are elevated in obese individuals with osteoarthritis and are independently associated with OA status beyond conventional measures of adiposity and systemic inflammation. These findings suggest that WISP1 may serve as a potential biomarker associated with metabolic-inflammatory processes. Given the cross-sectional nature of the study, the observed findings should be interpreted as associations, and causal relationships cannot be inferred. Further longitudinal and externally validated studies are needed to clarify its clinical utility and biological significance.