Experimental Study On Antiviral Effects Of Erding Granules Against Enterovirus71in Vivo And Vitro

Background and Objective：Enterovirus71（EV71）is a member of the genusEnterovirus within the family Picornaviridae and a common etiological agent of hand,foot and mouth disease（HFMD）, which can cause severe complications, such asneurogenic pulmonary edema, aseptic meningitis, brainstem encephalitis, myocarditisand acute flaccid paralysis, with a high mortality rate. There is no particularlyeffective antiviral drugs, vaccines and treatments for HFMD caused by EV71atpresent. Erding Granules are compound preparations which are made of4kinds oftraditional chinese medicine herba violae, lobelia, dandelion and radix isatidis. ErdingGranules have a function of heat-clearing and detoxifying. This study will test theeffects of Erding Granules against EV71in Vivo and Vitro, and on immune regulation,etc.Materials and Methods：In vitro experiments：MTT staining method was usedto measure toxic effects of Erding Granules and positive control（Ribavirin）in Verocells. Dose-effect curve was constructed by nonlinear regression to calculatenon-toxic concentration（TC0）and fifty percent toxic concentration（TC50）; Theinhibition rates of Erding Granules and Ribavirin against cytopathic effect（CPE）caused by EV71were measured under TC0. In vivo experiments：Animal model wasmade by EV71through intraperitoneal injection of5days aged rats, and then treatedwith Erding Granules and Ribavirin. Continual observation for14days, we recordedthe bodyweight and clinical scores and calculated the mortality and the rate of lifeextension.6days after infection, serum and muscle tissue were obtained to detect thecontent of inflammatory cytokines and viral load. HE staining was used to observe thechanges of muscle tissue in pathology.Results and Conclusions：In vitro experiments, Erding Granules gave a TC0at2.56mg/ml, a TC50of16.74mg/ml; Ribavirin gave a TC0at1.58mg/ml, a TC50at 18.17mg/ml. Erding Granules under the maximum non-toxic concentration of EV71inhibitory effect is not obvious, there was no statistically significant difference. Invivo experiments, treated with different doses of Erding Granules can improve rats’survival rate and survival time, increase the bodyweight, reduce clinical scores,reduce the content of IL-6, TNF-alpha, IFN-gamma, MCP-1in rats’ serum, alleviateinflammation, improve tissue pathology in different levels. Erding Granules treatmentdoes not inhibit amplification of EV71in muscle, the improvements of rats’ survivalstate and physiological indexes may associate with the regulation of inflammatoryfactors.