RESUMO
AIM: To investigate the effects of rosiglitazone on fibroblast-like synoviocyte ( FLS )-induced osteoclastogenesis in rheumatoid arthritis ( RA) and the related mechanism.METHODS: RA-FLS were cocultured with peripheral blood monocytes from healthy volunteers in the presence of macrophage colony-stimulating factor ( M-CSF) and rosiglitazone.Osteoclasts were assayed by tartrate-resistant acid phosphatase ( TRAP) staining.Resorption lacunae area was identified by toluidine blue staining and quantified by image analysis software.The mRNA expression of RANKL and OPG was evaluated by real-time PCR, and the protein levels of RANKL, OPG, p-ERK, p-p38 and p-JNK were measured by Western blot.RESULTS:Compared with control group ( without rosiglitazone treatment) , rosiglitazone at concentration of 15 μmol/L significantly decreased the number of osteoclasts (P0.05 ) . CONCLUSION:Rosiglitazone inhibits RA-FLS-induced osteoclast formation and its resorption activity by down-regulating RANKL expression and ERK phosphorylation, suggesting that rosiglitazone may inhibit RA osteoclastogenesis and bone re-sorption.