三白草水提液抗肠道病毒71型作用初探

Antiviral activity evaluation of water extracts of Saururus chinensis(Lour.) baill on enterovirus 71 infection

目的:初步探讨三白草水提液抗肠道病毒71型(EV71)的活性及其机制。方法:采用EV71感染非洲绿猴肾上皮(Vero细胞)模型,以不同浓度的三白草水提液提前预处理细胞,结合MTT方法检测细胞活力,采用TCID50的方法检测子代病毒的释放,评价三白草水提物抗EV71病毒能力。应用Realtime PCR的方法检查三白草水提物对炎症因子产生的作用。以免疫印迹法检测三白草水提物对NF-κB信号通路的影响。利巴韦林为阳性对照。结果:三白草水提物0. 1、0. 03、0. 015 mg/ml的浓度下能够显著抑制EV71感染诱导的细胞死亡,并且这种抑制作用具有剂量依赖性。与病毒组相比,三白草水提液在0. 1、0. 03以及0. 015 mg/ml的浓度下分别将病毒滴度降低了1. 60 logs、1. 85 logs和3. 45 logs。利巴韦林将病毒滴度降低了3. 54 logs。Realtime PCR的结果显示,三白草水提液能够明显降低EV71诱导的IL-1β、IL-6以及IL-8 m RNA的表达。提取核蛋白,免疫印迹检测结果显示,三白草水提物能够阻断EV71诱导的NF-κB核转移。结论:三白草水提液在体外具有抗EV71病毒复制的活性,并且可能通过抑制NF-κB核转移抑制炎症因子的产生。

Objective:To evaluate the antiviral activity of water extracts of Saururus chinensis(Lour.)Baill on enterovirus 71 infection.Methods:Vero cells were infected with EV71.Then the cells were treated with or without water extracts of Saururus chinensis(Lour.)Baill.Ribavirin was served as a positive reference drug.Cell viability was monitored by MTT assay and virus titers were tested by TCID50 method.The expression of cytokines was detected by Realtime PCR,while nuclear translocation of p-65/NF-κB were examined by Western blot assay.Results:Water extracts of Saururus chinensis(Lour.)Baill significantly inhibited EV71 induced cell death in a dose dependent way.Compared with the virus group,water extract at 0.1 mg/ml,0.03 mg/ml and 0.015 mg/ml decreased the virus titers by 1.60 logs,1.85 logs and 3.45 logs,respectively,while Ribavirin downregulated the virus titer by 3.54 logs.Moreover,water extract of Saururus chinensis(Lour.)Baill inhibited the mRNA level of IL-1β,IL-6 and IL-8.The results also showed that Water extracts of Saururus chinensis(Lour.)Baill can notably block the neuclear translocation of p-65/NF-κB,suggesting that EV71 blocked the expression of cytokines by bloking NF-κB signal pathway.Conclusion:Water extract of Saururus chinensis(Lour.)Baill possessed anti-EV71 activity and inhibited the expressions of cytokines by blocking the nuclear translocation of p-65/NF-κB.