Maria Sole Chimenti, Paola Conigliaro, Maria Morello, Rossella Zenobi, Paola Triggianese, Carlo Perricone, Lucia Novelli, Sergio Bernardini and Roberto Perricone
Rheumatoid (RA) and Psoriatic arthritis (PsA) are characterized by extensive synovitis resulting in bone destruction in both diseases and new bone formation in PsA. Objective: This prospective study analyzed interleukin (IL)-6, IL-17, IL-23, tumor necrosis factor (TNF)-α serum and synovial fluid (SF) levels and osteoprotegerin (OPG), bone-specific alkaline phosphatase (BAP) and D-vitamin (D-Vit) serum levels in RA and PsA patients before and after anti-TNF-α. Methods: 15 RA and 15 PsA patients with knee effusion and starting adalimumab (ADA) treatment were enrolled. Serum and SF from inflamed knee joint samples were obtained at baseline and after 24 weeks of treatment. Statistical analysis was performed using Graph Pad 5.0 statistical software. Results: In RA and PsA, SF IL-6, IL-17, and TNF-α were higher than serum levels while higher serum IL-23 was detected than in SF. Higher serum/SF IL-6, IL-23 and SF TNF-α were observed in RA than PsA, while serum IL-17 was higher in PsA than RA. Positive feedback among IL-6, IL-23, IL-17 and CRP and negative correlation between IL-17 and TNF-α in RA were found. In PsA, IL-23 correlated positively with IL-6. OPG correlated positively with ESR/CRP in RA and PsA. D-Vit correlated negatively with OPG and ESR in PsA. Higher BAP in RA than PsA and positive correlation with IL-6 in RA and with OPG in PsA were noticed. In PsA, IL-6 and OPG serum levels decreased significantly after 24 weeks ADA treatment. Conclusions: Distinct distribution of inflammatory cytokines and correlations with bone mediators were detected in RA and PsA. ADA affected inflammatory cytokines and bone mediators in PsA patients.