Adipokine Contribution to the Pathogenesis of Osteoarthritis

Figure 10

Expression of adipokines in large and small joints. Hand: Different studies have demonstrated that adiponectin may have a protective role in knee OA and it may be related to erosive hand OA [163, 164, 166]. Choe et al. showed that serum levels of resistin correlate with radiographic changes, in specific with subchondral erosions but with no pain [173]. Knee: there are multiple studies that show a higher level of leptin in synovial fluid and serum, and this correlates with the damage of the joint. The higher SF levels are thought to be related to the presence of infrapatellar fat (IFP) pad that produces leptin locally [215, 216]. Resistin and visfatin are produced by the IFP, and their levels correlate with joint damage and the levels of IL-6. Resistin also correlates with menisci damage. Hip: even though the hip and knee are under similar stress conditions, the clinical features and the adipocytokine profile are different, with lower levels of leptin and higher adiponectin, resistin, and visfatin levels within the joint. Only the levels of visfatin correlate with hip pain [140]. Shoulder: the leptin and adiponectin levels correlate with joint damage, but appear to have a different profile of adipocytokines in shoulder, with lower SF and serum levels of leptin and adiponectin, but a higher serum/SF ratio for both, especially adiponectin [168].