紫草多糖抑制LPS活化PBMC表达炎症相关因子的基因转录

Arnebia euchroma polysaccharides inhibit expression of inflammation-related cytokines in LPS-stimulated PBMC

目的：研究紫草多糖对LPS活化外周血单个核细胞（Peripheral blood mononuclear cells,PBMC）表达TNF-α、IL-10、IL-18相关因子的影响及其可能的信号通路。方法：LymphopreTM（1.077 g/ml）淋巴细胞分离液离心分离正常健康人PBMC,紫草多糖处理正常健康人的PBMC或LPS活化的PBMC,利用Real-time RT-PCR法检测TNF-α、IL-10、IL-18、IL-18BP、IL-18Rα、IL-18Rβ基因转录水平,通过Western blot检测PBMC中ERK磷酸化水平。结果：紫草多糖可增强PBMC TNF-α、IL-10、IL-18Rα、IL-18Rβ的转录,与LPS处理的PBMC相近。紫草多糖处理LPS活化的PBMC,在处理早期（4小时）可抑制LPS活化的PBMCTNF-α及IL-18的表达,抑制率达15%50%（P〈0.05）;并可抑制LPS诱导的ERK磷酸化,抑制率达27%61%（P〈0.05）。结论：紫草多糖可能是通过抑制PBMC的MAPK信号通路进而抑制LPS诱导的炎症相关因子TNF-α等高表达。

Objective：To study the effects of Arnebia euchroma polysaccharides on TNF-α,IL-10 and IL-18.mRNA expression in LPS-stimulated peripheral blood mononuclear cells（PBMC） and to explore the possible signaling pathways.Methods：PBMC were isolated from peripheral blood of healthy people by LymphopreTM.After the treatment of culturing human peripheral blood mononuclear cells（PBMC） or LPS stimulated PBMC,in presence or absence of Arnebia euchroma polysaccharides the transcription levels of TNF-α,IL-10,IL-18,IL-18BP,IL-18Rα,IL-18Rβ were detected by Real-time RT-PCR.The phosphorylation of ERK in PBMC was detected by Western blot.Results：The transcription levels of TNF-α,IL-10,IL-18Rα and IL-18Rβ in PBMC induced by Arnebia euchroma polysaccharides were similar to that treated by LPS.Arnebia euchroma polysaccharides inhibited transcription of inflammatory mediators,TNF-α and IL-18 mRNA at 4 h in LPS-stimulated PBMC（inhibition ratio,15%-50%,P〈0.05）,and inhibited LPS-induced phosphorylation of ERK（inhibition ratio,27%-61%,P〈0.05）.Conclusion：Arnebia euchroma polysaccharides may inhibit LPS-induced TNF-α expression in LPS-stimulated PBMC via down-regulation of MAPK signaling pathway.