卷柏多糖对肠道病毒71型复制的体外抑制作用

Inhibition of EV71 replication in vitro by polysaccharides from Selaginella tamariscina

目的研究卷柏多糖对EV71病毒复制的体外抑制活性。方法将卷柏多糖不同提取物设置不同剂量作用于人恶性横纹肌肉瘤细胞(RD),采用细胞病变效应(CPE)及细胞计数试剂盒(CCK8法)检测细胞存活率,并计算药物的半数中毒浓度(CC50);培养EV71感染的RD细胞,建立体外病毒感染模型,并设立正常细胞对照组和阳性药物对照组(利巴韦林3.2mg/L),将卷柏多糖不同提取物设置不同剂量作用于EV71感染后的RD细胞,应用CCK8法检测药物抗病毒抑制率,并计算药物的半数抑制浓度(IC50);收集药物作用于感染后RD细胞的培养液上清,进行荧光定量PCR检测,观察药物对EV71病毒RNA表达的影响。结果卷柏30%醇沉多糖和50%醇沉多糖对RD细胞的CC50值分别为396和142 mg/L,抑制EV71病毒致CPE的IC50值分别为40.8和26.2 mg/L。与病毒感染对照组相比较,卷柏30%和50%醇沉多糖作用后,经EV71感染的RD细胞培养液中病毒RNA拷贝数显著降低(P<0.05)。结论卷柏及其30%和50%醇沉多糖可以作为新的抗EV71的潜在药物。

Objective To evaluate the inhibitory effect of polysaccharides from Selaginella tamariscina on Enterovirus 71（EV71） replication in vitro.Methods For detecting the cytotoxicity,series of doses of polysaccharides from Selaginella tamariscina were added in RD cells,cell survival rates were evaluated by observing the cytopathic effect（CPE） and using cell counting Kit-8（CCK8） assay,then the half toxic concentration（CC50） of the drugs were calculated.For studying the antiviral activity,the cellular model was established by infecting RD cells with EV71.Several groups were set in the experiments： normal control group,virus-infected group,positive drug treated EV71-infected group（ribavirin 3.2 mg/L） and series of doses of polysaccharides treated EV71-infected groups.The CPE inhibitions were determined by using CCK8 assay and the half inhibitory concentrations of drugs（IC50） were calculated.The inhibitiory effect of polysaccharides on EV71 RNA were determined by using real-time RT-PCR methods for detecting the virus RNA levels in cell cultures.Results The CC50 of 30% and 50% alcohol precipitated polysaccharides from Selaginella tamariscina on RD cells were 396 and 142 mg/L,respectively;the IC50 calculated according to the CPE inhibitory rates were respectively 40.8 and 26.2 mg/L.Additionally,these two polysaccharides significantly reduced viral RNA copies in EV71-infected RD cells.Conclusion Selaginella tamariscina together with its 30% and 50% alcohol precipitated polysaccharides can be developed as potential new anti-EV71 drugs.