琼枝麒麟菜多糖抗单纯疱疹病毒2型活性研究

Study on the anti-herpes simplex virus activity of Eucheuma gelatinae polysaccharide

目的探讨琼枝麒麟菜多糖(EGP)抗单纯疱疹病毒2型(HSV-2)的活性及其作用机制。方法联合采用观察细胞病变效应(CPE)法和MTT法评价EGP对Vero细胞的毒性。空斑减数实验检测EGP对HSV-2的综合抗病毒活性、直接灭活作用、吸附及进入细胞过程的抑制作用、和感染后的治疗作用。Real-time PCR(RT-PCR)检测EGP对HSV-2基因表达及其DNA复制的影响。结果 EGP浓度低于125μg/mL对Vero细胞无毒性。EGP具有较强的综合抗病毒活性,在实验所用最低浓度(1.95μg/mL)下,EGP可达到80%的HSV-2病毒抑制率。EGP对HSV-2具有很强的直接灭活和抑制吸附作用,治疗作用相对较弱。同时,EGP可以下调HSV-2早期基因UL52和晚期基因UL27的表达,但是对病毒的DNA复制过程无影响。结论麒麟菜多糖具有显著的抗HSV-2感染活性,主要通过干扰病毒对细胞的粘附、侵入而发挥作用。

Objective To determine the activity of Eucheuma gelatinae polysaccharide（EGP）on the replication of herpes simplex virus type 2（HSV-2）.Methods The maximum tolerance concentration of EGP to Vero was screened by cytopathic effect（CPE）method and MTT method.The antiviral effects of EGP were verified by plaque reduction assay via described protocols,such as direct inactivation,adsorption and penetration inhibition and virucidal effect.The viral gene expression was also monitored by real-time PCR（RT-PCR）.Results No toxic effect was observed,when the concentration of EGP kept lower than 125μg/mL in Vero cells.EGP inhibited 80% of HSV-2 at 1.95μg/mL,which was the lowest concentration of EGP used in this experiment.EGP prevented early HSV-2 infection through directly inactivation and impairment of virus attachment.But EGP couldn＇t prevent viral penetration.RTPCR demonstrated that EGP also inhibited the RNA synthesis of HSV-2 early gene and late gene,but EGP didn＇t cause any change in viral replication.Conclusion EGP showed high anti-HSV activity but low toxicity which represented that it could be a potential viral inhibitor.