Study On Antivirus Effects Of The Traditional Chinese Medicine Sargassum Extract

Objective To clear the inhibitory activity of the extract of Sargassum fusiforme on respiratory syncytial virus(RSV)and enterovirus 71(EV71).Methods Firstly,6 kinds of seaweed were extracted by means of water extraction and alcohol precipitation,whereafter conducted an experiment of resisting RSV and EV71 in vitro with method of cytopathic effect(CPE).Compared their antiviral activity,screening out the best to do antiviral experiment against 7 kinds of viruses.Secendly,RSV intranasally infected young mice to establish RSV pneumonia model,intraperitoneal injection for drug delivery route.Seted normal control group,virus control group,positive control group,drug group,then compared the lung index of mice lung index,inhibition rate and observed results of Real-Time PCR for lung tissue' viral genome,dealed with lung tissue pathological section by hematoxylin-eosin staining(HE).Three types of dosing mode which including prevention,treatment and pre mixed were applied in 96 well plates of EV71 in vitro experiments.Detected EV71 genome replication of 4 experiental group growing in 6 hole board by Real-Time quantitative PCR.Observed and took pictures of GFP-EV71 under the fluorescence microscope.Gene Chip primeview human scanning was used to find potential targets on cells infected by EV71 after treated with ESF.Results (1)The therapeutic index of 6 kinds of seaweed as follow,RSV of the antiviral effect: Sargassum fusiforme > Sargassum pallidum > Gulfweed > Cladophora >Sargassum thunbergii > Ulva > Ribavirin.EV71 of the antiviral effect: Sargassum fusiforme > Cladophora > Sargassum pallidum > Gulfweed > Sargassum thunbergii >Ulva > Ribavirin.The therapeutic index of extract of Sargassum fusiforme to 7 kinds of viruses: EV71 > Cox A16 > RSV > Cox B3 > Cox B5 > Cox B2.(2)The mice lung index inhibition rate: Ribavirin < ESF of low dose < ESF of middle dose < ESF of high dose.The result of Real-Time PCR displayed that RSV gene' expression in lung tissue of mice in ESF group was in low abundance.The observation of mouse lung tissue pathological slices stained with HE indicated that ESF confered protection on mouse lung that infected RSV.(3)The therapeutic index of directly killing group about anti-EV71 mechanism study in preliminary experiments in vitro was 512,higher than the prevention group(32)and treatment group(8).The result of Real-Time PCR about EV71 showed that viruses' gene expression of ESF group was in low abundance.The activity of GFP-EV71 increases with the rise of concentration of ESF which observed under fluorescence microscopy.Finaly,the channel and gene ontology with significant difference were found with the method of Gene Chip primeview human scanning,whose level increased or decreased dramaticlly.Conclusions Sargassum fusiforme which is the source of Chinese medicine “seaweed”has excellent antiviral effect on RSV and EV71,and the higher the concentration of ESF is,the better lung protective effect on pneumonia mice is.The directly killing effect of ESF to EV71 was the highest,ESF can kill EV71 before EV71 infects cells.For the potential targets of ESF in the host cells,a series of channels and genes were given through the Gene Chip primeview human scanning which need experiments like western blot to testify.