类风湿关节炎患者PBMC中凋亡相关蛋白Bcl-2与c-FLIP的表达及其意义

Expression and significance of apoptosis-related proteins Bcl-2 and c-FLIP in peripheral blood mononuclear cells of patients with rheumatoid arthritis

目的探讨类风湿关节炎(RA)患者外周血单个核细胞(PBMC)中凋亡相关蛋白Bcl-2与c-FLIP的表达水平及其临床意义。方法 60例类风湿关节炎患者外周血标本按RA疾病活动指数(DAS28)分为低度活动期(DAS28 <3. 2)、中度活动期(DAS28 3. 2～5. 1)与高度活动期(DAS28> 5. 1),以同期25例健康体检者外周血作为健康对照组(N组)。实时荧光定量PCR法检测RA患者PBMC中Bcl-2、c-FLIP、caspase-8凋亡相关蛋白的mRNA表达水平;蛋白免疫印迹法检测PBMC中cFLIP、caspase-8蛋白表达水平。结果 Bcl-2的低活动组mRNA相对表达量为1. 02±0. 35,高于健康对照组(0. 32±0. 18,P<0. 05),而中、高活动组分别为0. 08±0. 01,0. 05±0. 02,低于健康对照组(均P <0. 05)。c-FLIP的低、中、高三个活动组mRNA相对表达量分别为1. 27±0. 28,1. 32±0. 34,1. 93±0. 40,均高于健康对照组(1. 08±0. 12,均P <0. 05); caspase-8的低、中、高组mRNA相对表达量分别为2. 77±0. 97,4. 52±0. 85,2. 13±0. 44,也均高于健康对照组(均P <0. 05)。中活动组cFLIP蛋白表达明显高于健康对照组(P <0. 05),而低、高活动组与对照组差异无统计学意义(P> 0. 05);中、高活动组caspase-8蛋白表达明显高于健康对照组(P <0. 05),而低活动组表达差异无统计学意义(P> 0. 05)。结论 PBMC中凋亡相关蛋白c-FLIP mRNA表达水平随着RA疾病的进程增高,而Bcl-2只有低活动组有明显增高,此可为类风湿关节炎发病机制的后续研究提供参考。

Objective To investigate the expression and its significance of apoptosis-related proteins Bcl-2,c-FLIP and caspase-8in peripheral blood mononuclear cells of patients with rheumatoid arthritis(RA).Methods The blood samples of60patients with rheumatoid arthritis were divided into low activity(DAS28<3.2)group,moderate activity(3.2-5.1DAS28)group and high activity(DAS28>5.1)group according to the RA disease activity index(DAS28).The blood of25normal controls for health check-up were used as normal control group.The mRNA expression of apoptosis related proteins Bcl-2,c-FLIP and caspase-8was detected by realtime PCR,and the protein levels of c-FLIP and caspase-8were detected by Western blot.Results The mRNA expression of Bcl-2in low activity group was higher than in normal control group(P<0.05),but it was lower in moderate activity group and high activity group(P<0.05).The relative mRNA expression of c-FLIP in low activity group,moderate activity group and high activity group were higher than that in normal control group respectively(P<0.05).The expression level of Caspase-8mRNA was higher in low activity group,moderate activity group and high activity group than in normal control group(P<0.05).The protein level of c-FLIP in moderate activity group was significantly higher than that in control group(P<0.05),but there was no difference between low activity group and normal control group.The protein levels of Caspase-8in moderate activity group and high activity group were significantly higher than that in normal control group(P<0.05),but there was no difference between low activity group and normal control group.Conclusion In peripheral blood mononuclear cells of patients with RA,the relative mRNA expression level of c-FLIP is increased with the progress of the disease,while Bcl-2mRNA increases only in low activity patients compared with normal controls,but decreases in moderate and high activity patients.It provides reference for the further study of the pathogenesis of rheumatoid arthritis.