Correlation of synovial fluid leptin concentrations with the severity of osteoarthritis

Abstract

Leptin is known to play an important role in the pathophysiology of osteoarthritis (OA). This study investigated whether synovial fluid (SF) leptin level is related to the radiographic severity of OA and its role as a quantitative marker for the detection of OA. SF was obtained from 42 OA patients who underwent knee surgery and 10 who had no abnormality of articular cartilage during arthroscopic examination. The progression of OA was classified by Kellgren-Lawrence grading scale. The concentrations of leptin were measured with commercial enzyme-linked-immunosorbent serologic assay kits. Median leptin concentrations in SF were significantly higher in OA patients (median 4.40 ng/ml; range 0.5-15.8) compared to controls (median 2.05 ng/ml; range 1.0-4.6; P = 0.006). SF leptin levels showed significant difference according to the severity of OA (P = 0.0125). Median SF leptin level was highest in stage IV patients (11.1 ng/ml), which was significantly higher compared to all other groups including controls (P < 0.05). Age showed a significant positive correlation with leptin concentrations in OA patients (P < 0.05), but not in controls. These results demonstrate that SF leptin concentrations were closely related to the radiographic severity of OA, suggesting that SF leptin levels could be used as an effective marker for quantitative detection of OA.

Differential Signalling Through ALK-1 and ALK-5 Regulates Leptin Expression in Mesenchymal Stem Cells

“…Leptin is considered a pro-inflammatory peptide in rheumatic diseases, whereas it is not expressed in healthy cartilage [24,25]. Indeed, recent works have shown that leptin inhibits chondrogenesis [26].…”

Correlation between plasma and synovial fluid basic fibroblast growth factor with radiographic severity in primary knee osteoarthritis

“…Even though plasma and/or synovial fluid levels of several cytokines and growth factors have been studied in patients with knee OA, to our knowledge, there has been no published data regarding the association of circulating and synovial fluid levels of bFGF in various clinical stages of primary knee OA [3,9,10,15,23]. Accordingly, we hypothesised that bFGF in plasma and synovial fluid could be correlated with the severity of clinical outcomes in knee OA patients.…”

Cardiometabolic comorbidities and rheumatic diseases: Focus on the role of fat mass and adipokines

“…Adiponectin stimulates PGE 2 and IL-8 production in RA synovial fibroblast (93,94). In addition, it was also reported in RA synovial fibroblast that adiponectin is able to stimulate the production of IL-6, PGE 2 , vascular endothelial growth factor, and MMP-1 and MMP-13 (43,95). In cultured chondrocytes, adiponectin also induces the production of NO, IL-6, MMP-3, MMP-9, and monocyte chemotactic protein 1 (MCP-1) (96).…”

“…It is known that leptin expression is much higher in human OA cartilage than in normal cartilage. Moreover, leptin expression in chondrocytes, as in synovial fluid, correlates with the severity of the disease (42)(43)(44). Considering the sexual dimorphism of leptin circulating levels, it has been hypothesized that the increased predisposition of women to develop OA could be due to the higher circulating levels observed in women in comparison with men (45).…”