小儿热速清口服液防治EV71型手足口病的体内外作用研究

Antiviral Effect of Xiao'er Resuqing(小儿热速清)Oral Liquid Against Enterovirus 71-infected Hand,Foot,and Mouth Disease In Vitro and In Vivo

目的:探讨小儿热速清口服液对EV71型手足口病(HFMD)模型体内外防治作用及机制。方法:采用3 d龄BALB/c乳鼠腹腔注射EV71H株建立BALB/c乳鼠手足口病模型,分为模型对照组、利巴韦林对照组、小儿热速清15.5、31、62 mL/kg组,另设正常对照组。进行预防性给药和治疗性给药评价。观察乳鼠的每日感染程度、动物死亡数,计算各组动物平均存活天数、死亡率、死亡保护率及生命延长率。RT-PCR法检测后肢肌肉组织病毒载量;CBA法检测血清中IL-6、IFN-γ的含量;比色法检测心肌组织中AST的含量;组织病理学检测心、后肢肌肉组织病理变化。采用CPE法观察其对EV71 H株在Vero细胞增殖的抑制作用。结果:小儿热速清口服液对肠道病毒EV71感染BALB/c乳鼠模型具有明显的保护作用,31、62 mL/kg组可以明显降低感染积分程度、死亡率,延长存活天数(P<0.05或P<0.01),可以明显降低后肢肌肉组织病毒载量、血清中IL-6含量、心肌AST活力(P<0.05或P<0.01);明显改善后肢肌肉组织病理变化(P<0.05或P<0.01)。对EV71 H株致Vero细胞病变有一定的抑制作用,TI值为3.98,并能明显降低EV71 H株感染细胞的病毒载量(P<0.05)。结论:小儿热速清口服液对EV71型手足口病具有较好的预防和治疗作用,可能通过直接抑制病毒复制、抑制炎症因子分泌、改善心肌功能发挥作用。

Objective:To investigate the antiviral effect of Xiao'er Resuqing(小儿热速清)Oral Liquid on the model of Enterovirus 71(EV71)-infected hand,foot,and mouth disease(HFMD)in vivo and in vitro and its mechanism.Methods:BALB/c suckling mice,3-day-old,were intraperitoneally injected with EV71H to induce the BALB/c suckling mouse model of HFMD.Mice were divided into a normal group,a model group,a ribavirin group,and Xiao'er Resuqing Oral Liquid groups(62,31,and 15.5 mL/kg)and were treated with therapeutic administration and preventive administration.After administration,the daily infection rate and mortality were observed,and the mean survival time,mortality rate,death protection rate,and life extension rate in each group were calculated.Real-time polymerase chain reaction(RT-PCR)was used to detect the viral loads in hind limbs.The CBA method was used to detect the content of interleukin-6(IL-6)and interferon-(IFN-).The colorimetric method was used to detect the content of aspartate aminotransferase(AST)in myocardial tissues,and the histopathological changes in hind limbs and myocardial tissues were determined.The CPE method was used to detect the inhibitory effect of EV71H on Vero cell proliferation.Results:Xiao'er Resuqing Oral Liquid showed a significant protective effect on the BALB/c suckling mouse model of EV71 infection.In the Xiao'er Resuqing Oral Liquid group(31 mL/kg),the daily infection rate,mortality rate,and life extension rate were increased(P<0.05 or P<0.01),the viral load in hind limbs,IL-6 content,and AST activity were decreased significantly(P<0.05 or P<0.01),and the pathological changes in hind limbs were improved(P<0.05 or P<0.01).Xiao'er Resuqing Oral Liquid also effectively inhibited Vero cytopathia induced by EV71H strain,with a therapeutic index(TI)of 3.98,and it significantly reduced the viral load of cells infected by EV71H(P<0.05).Conclusion:Xiao'er Resuqing Oral Liquid shows a good preventive and therapeutic effect on EV71-infected HFMD.Its mechanism may be related to the direct inhibition of virus replication and inflammatory factor secretion and the improvement of myocardial function.