Effects Of Glutamate On The Secretion Of Cytokines In Fibroblast-Like Synoviocytes Of Rheumatoid Arthritis

Objective Glutamate(Glu)signals may play an important role in the pathogenesis of rheumatoid arthritis(RA).This study aims to analyze the effects of different concentrations of Glu on secretion of interleukin-17(IL-17)and tumor necrosis factor alpha(TNF-?)in cultured RA fibroblast-like synoviocytes(FLS),explore the role of Glu in development of RA.Methods In this study,synovial tissues were obtained from RA patients undering joint operation.The primary cells were cultured,and the 3-5 generation cells were used for the experiment.FLS in better growth condition was observed under microscope.Glu was divided into4 groups according to the different concentrations:A group(blank group),B group(100umol/L Glu),C group(500umol/L Glu),D group(1000umol/L Glu).IL-17 and TNF-? were detected by ELISA after Glu stimulation of 15 h on RA-FLS.The experiment was repeated three times.The statistical analysis was carried out by SPSS19.0 software.Results(1)RA-FLS itself without any stimulation could secrete IL-17 and TNF-?;(2)The influence of Glu on RA-FLS secretion IL-17 suggested: the differences between A-B group,A-D group,B-D group,C-D group were significant(P<0.05,P<0.01,P<0.01,P<0.01),but there were no significant differences between the other groups.That was,when at the concentration of100umol/L,Glu stimulated RA-FLS secreting more IL-17,However,Glu inhibited the secretion of IL-17 at 1000umol/L.(3)The influence of Glu on RA-FLS secretion TNF-? showed: A group had significant difference between D group(P<0.05),and there were no significant differences between the other groups.That was,when the concentration of Glu was 100umol/L or 500umol/L,the effect of Glu on the secretion of TNF-? in RA-FLS had not Statistical different with no Glu stimulation.Glu inhibited RA-FLS secreting TNF-? at 1000umol/L.Conclusion Glu can regulate RA-FLS secreting IL-17 and TNF-? by different concentrations.Low concentration of Glu stimulates IL-17 secretion on RA-FLS,but when the concentration is high at 1000umol/L,Glu inhibits RA-FLS secreting IL-17 and TNF-?.