Expression And Clinical Research Of Glutamate In The Serum Of Patients With Rheumatoid Arthritis

Objective Glutamatergic signaling play possible role in the pathogenesis of joint diseases such as rheumatoid arthritis(RA).We aimed to analyze the expression levels of glutamate(Glu),IL-17 and TNF-? in serum of patients with rheumatoid arthritis(RA)and investigate the clinical significance of Glu in RA.Methods A total of 34 RA patients were enrolled and 20 healthy subjects were enrolled as healthy control group.We collected serum from 54 cases enrolled.Glu,IL-17 and TNF-? levels were determined by enzyme-linked immunosorbent assay(ELISA),serum Glu levels were detected in 20 cases healthy controls by the same way.We recorded laboratory index and clinical parameters during the same period when drew patients blood.Compare the differences of Glu in RA group than healthy control group and pearson correlation analysis were used to define the correlation of Glu,IL-17andTNF-?.RA patients were divided into bone erosion group and non-bone erosion group and compare the differences of Glu,IL-17 and TNF-? in the two groups.Analysis the correlation between Glu and IL-17,TNF-a,clinical parameters of RA patients.Results(1)The levels of Glu were significantly higher in RA group than healthy control group[(14.16�7.76)?mol/L vs(11.31�1.08)?mol/L,P =0.003].(2)The levels of Glu,IL-17,TNF-a in serum were higher in the bone-erosion group than the no bone-erosion group [(16.53�10.35)?mol/L,(273.44�114.31)pg/mL,(169.95�92.58)pg/mL vs(14.79�4.90)?mol/L,(203.62�62.18)pg/mL,(107.49�56.42)pg/mL].(3)The levels of Glu in RA group were positively correlated to IL-17,TNF-a,visual analogue scale(VAS)scores,disease activity score in 28 joints(DAS28)and tender joint count,however no correlation with ESR,CRP,anti-CCP antibody and swollen joint count.Conclusions(1)Compared to healthy controls,serum Glu levels were significantly higher in RA group which illustrated that Glu may be involved in the pathogenesis of RA.(2)The levels of Glu in serum were significantly higher in the bone-erosion group than non-bone erosion group,and were positively correlated to IL-17,TNF-a.While IL-17,TNF-a were associated with RA bone destruction,thus Glu may be involved in the occurrence of RA.(3)The levels of Glu in RA group were positively correlated to visual analogue scale(VAS)scores and tender joint count,however VAS scores and tender joint count were related to pain,so Glu may be involved in RA inflammatory pain.