Oxidative Stress Up-Regulate IL-17 In Go Patients

Objective To research the role of cytokine interleukine-17 ( IL-17 ) in the pathogenesis of Graves' ophthalmopathy(GO) , and investigate the relationship between IL-17 and oxidative stress in GO.MethodsTwenty-five newly diagnosed GO patients in active status as GO group and fifteen healthy subjects as control group participated in this study. Clinical activity score (CAS) and severity (NOSPECS) of GO were examined.Peripheral blood samples were obtained from each subject and measured for Serum FT3,FT4,μTSH,TRAb,TPOAb,TgAb,IL-17and activity of monohydrate/superoxidedismutase .Ten controls and patients selected from this study,from whom venous blood obtained and isolated for T lymphocytes . Then T lymphocytes cultured in the presence of low concentrations of H₂O₂ and/or Vitamin C(VitC) for 48 hours. All T lymphocytes were divided into four groups: blank group(H₂O₂ =0,VitC =0),H₂O₂ group(H₂O₂ =1 000 nM,VitC=0), VitC group(H₂O₂ =0,VitC =25μM),H₂O₂+VitC(H₂O₂ =1 000 nM ,VitC =25μM ).Culture supernatants were harvested and examined for IL-17.All the statistics were analysised by SPSS 17.0.Results1. All the GO patients were with CAS≥3 points (rang 3-6,mean 4.88±0.93),NOSPECS≥3(rang 3-5,mean3.56±0.65).2. In GO patients, the mean serum FT3(13.49±4.96 vs. 3.11±0.16 pg/ml),FT4(6.03±2.64 vs. 1.24±1.36 ng/dl),TPOAb(300.38±233.05 vs.44.20±37.51 IU/ml),TgAb(1542.54±1614.51 vs.59.52±34.66 IU/ml),TRAb ( 19.41±3.77 vs.12.47±1.15U/L ) and IL-17 ( 10.15±0.93 vs.13.62±2.43 ng/L ) were significantly higher than that in controls (P﹤0.05),μTSH(0.02±0.02 vs.1.24±0.14 mIU/L)was significantly lower. There was no significant differences in age(30.00±5.30 vs.31.04±8.33)(P>0.05). Serum IL-17 positively correlated with CAS(r=0.43,P=0.03).3. The mean serum MDA in GO patients were significantly higher than that in normal controls (6.77±1.11 vs. 4.16±0.61nmol/ml)(P﹤0.05),SOD(53.95±17.53 vs. 73.16±15.33U/ml)were significantly lower(P﹤0.05). Surem MDA and IL-17 were positively correlated in GO (r=0.490,P=0.046).No correlation were observed between CAS/ NOSPECS and SOD/MDA(P﹤0.05).4.Culture supernatants level of IL-17 in GO patients were significantly higher in H₂O₂ group > blank group >VitC and H₂O₂+VitC groups (P﹤ 0.05).There was no statistics differences among all T lymphocytes groups in controls(P>0.05).Conclusion1.Serum IL-17 was significantly higher in Graves' ophthalmopathy(GO), and positively correlated with CAS,which may play an important role in the pathogenesis of GO .2.Oxidative stress up-regulate IL-17in GO patients ,the effect could be blocked by vitamin C by certain extent.