Résumé
To elucidate the involvement of adipocytokines "Adiponectin" in the pathogenesis of rheumatoid arthritis [RA] by measuring serum and synovial fluid levels of adiponectin in RA patients and also by evaluating its expression in RA synovial tissue to find out its possible role in disease activity and severity in order to throw light on possible new strategy in the management of RA. Twenty RA patients and ten subjects with acute post traumatic knee effusion - who served as a control group-were recruited for this study. Serum adiponectin levels were measured using enzyme linked immunosorbent [ELISA]. Synovial fluid [SF] levels of adiponectin, IL-6 and pro MMP-1 were measured by ELISA. Modified disease activity score [DAS] and Larsen score were assessed in RA patients. Synovial tissue [ST] specimens were obtained from control subjects and RA patients. These specimens were assessed immunohistochemically for adiponectin and graded in a semiquantitative scale. Serum adiponectin was significantly raised in RA patients compared to controls [p<0.05]. There was a highly statistically significant increase in SF adiponectin, SF Pro MMP-1, ST adiponectin expression in RA patients compared to controls [p<0.01], while there was a significant increase in SF IL-6 in RA patients compared to controls [p<0.05]. SF adiponectin correlated positively with each of ST adiponectin expression, SF IL-6, SF pro MMP-1 [p<0.01]. A highly significant positive correlation was found between SF levels of adiponectin and each of DAS and Larsen score [p<0.01]. Adiponectin is expressed in the RA synovium and it stimulates the production of key mediators of destructive arthritis, IL-6 and pro MMP-1, so targeting the proinflammatory cascade of adiponectin may represent an exciting new therapeutic tool in RA