马齿苋多糖对猪流行性腹泻病毒抑制作用的研究

Inhibitory effect of Portulaca oleracea polysaccharide on porcine epidemic diarrhea virus

提取马齿苋多糖(POP),研究它对猪流行性腹泻病毒(PEDV)体外复制的作用及机制。采用醇沉法提取POP并用纯化,选用VH细胞为模型细胞,检测纯化后的多糖对该细胞的细胞毒性。用PEDV感染VH细胞,建立体外病毒感染模型,用CCK-8和RT-q PCR的方法检测POP对细胞的保护和对病毒的抑制效果以及作用于病毒感染的时期,免疫荧光观察其对病毒复制的作用,并通过ELISA方法检测POP对体外PEDV感染模型分泌IFN-α、TNF-α、IL-6等细胞因子的影响。结果显示,POP浓度在0~25 μg/m L范围内对VH细胞无毒副作用;浓度为6.25~25 μg/m L时对PEDV具有明显的抑制作用,并呈一定的剂量依赖性,免疫荧光可以清晰观察到其对病毒复制的抑制作用。该药物主要作用于病毒感染的吸附期;其对PEDV感染引起的细胞因子IFN-α、TNF-α和IL-6的分泌的抑制作用显著(P<0.01)。由此得出:POP对PEDV感染的VH细胞具有明显的抑制作用,能抑制PEDV感染引起的细胞因子IFN-α、TNF-α、IL-6的蛋白含量的增加,从而发挥抗病毒的作用。

Portulaca oleracea polysaccharide(POP)was extracted to study its effect and mechanism on PEDV replication in vitro.The POP was extracted by alcohol precipitation method and purified, and VH cells were selected as model cells to detect the cytotoxicity of the purified polysaccharide on the cells.We infected VH cells with PEDV,established a virus infection model in vitro,and used CCK-8 and RT-q PCR to detect the protection of POP on cells and the inhibitory effect on the virus,as well as the period of action;and we detected POP to PEDV infection in vitro by ELISA.The model secretes the effects of cytokines such as IFN-α,TNF-α,and IL-6.The results showed that the POP concentration in the range of 0-25μg/m L had no toxic side effects on VH cells;the concentration of 6.25-25μg/m L had a significant inhibitory effect on PEDV in a dose-dependent manner;the drug mainly acts on the virus.The adsorption period of infection;it has a significant inhibitory effect on the secretion of cytokines IFN-α,TNF-αand IL-6 induced by PEDV infection(P<0.01).It is concluded that POP has a significant inhibitory effect on PEDV-infected VH cells,and can inhibit the increase of the protein content of cytokines IFN-α,TNF-α,and IL-6 caused by PEDV infection,thereby exerting an antiviral effect.