Effect of total glucosides of paeony on the proliferation of fibroblast-like synovial cells in osteoarthritis

Objective To investigate the proliferative characteristics of fibroblast-like synovial cells (FLS)in osteoarthritis in vitro and the mechanism of the immunosuppressive effect of total glucusides of paeony(TGP).Methods FLS of OA and non-inflamed synovium(NS)were cultured and identified in vitro in the presence or absence of TGP.After incubation,the survival fraction(SF)of FLS was evaluated by MTI' and the TNF-α,IFN-γand bFGF level in cultured FLS supernatant was measured by ELISA.The expression of FLS c-los mRNA and cell cycle of OA-FLS was observed by RT-PCR and flow eytometry respectively at the same time.Results No statistical significant differences were noted between the OA and NS FLS in pro- liferating double time.High doses of TGP suppressed FLS-SF more evidently in OA patients than in NS(P0.05).The SF of FLS interfered by TGP was lower than that of no drug control(P0.05).The TNF-α,bFGF level in OA-FLS supernatant was depressed and IFN-γwas increased,the accumulation of c-fos mRNA was reduced when FLS cultured with 2000 mg/L or 400 mg/ml TGP(P0.05).The TGP could change the cell cy- cle of FLS,prolong G_1 phase and shorten S phase at dose of 2000 mg/ml,but no statistical significant differ- ences were observed(P0.05).Conclusion High dose TGP can inhibit OA-FLS proliferation,modulate cy- tokine secretion and c-fos expression in OA.This suggests that TGP has immunosuppressive effect on OA syn- ovitis,probably by preventing the synovial hypertrophy in OA.