Initial Research About EGCG Anti-Grass Carp Reovirus And Its Pharmacokinetics In Grass Carp?Gobiocypris Rarus And Penaeus Vannamei

(-)-Epigallocatechin gallate(EGCG)is a small molecular substance with a variety of biological activities.It is derived from tea polyphenols in green tea and has natural antioxidant activity,anticancer activity,antiviral function and immunity enhancement.A number of studies have shown that EGCG standards have a certain inhibitory effect on Grass Carp Reovirus(GCRV)and White Spot Syndrome Virus(WSSV).Gobiocypris rarus as a new model organism highly sensitive to GCRV virus,can provide experimental samples for the later EGCG antiviral research at the fish level.In this study,EGCG anti-GCRV virus was verified at the cellular level by using 35%,50%,and 99% three concentrations of EGCG crude extract.To explore the effects of EGCG on different cell activities and various enzyme activities in grass carp plasma after administration.To study the pharmacokinetics of EGCG in grass carp,Gobiocypris rarus and Penaeus vannamei,and provide reference for later clinical drug use.The main findings are as follows:1.EGCG crude extract can effectively inhibit GCRV infection of CIK cellsAfter cultivating grass carp kidney cells(CIK)with different concentrations of EGCG crude extract,infected with GCRV virus,observe the replication of the virus infection,the expression of GCRV virus in the supernatant of the cells was detected by real-time PCR.The results showed that with the increase of the concentration of crude EGCG in CIK cells,the efficiency of GCRV adsorption and infection was significantly reduced,the cytopathic effect(CPE)in the cells was significantly reduced,and the virus titer in the cell supernatant was also significantly decreased.It was proved that the crude EGCG extract had a good effect of inhibiting the infection of GCRV virus.2.EGCG crude extract is a safe and non-toxic green drug for fishIn order to explore the safety of EGCG crude extract.In this study,CIK,grass carp ovary(CGO),fathead minnow(Pimeohales promelas,FHM)and Epithelioma papulosum cyprinid(EPC)were incubated with 35%,50% and 99% concentrations of EGCG crude extracts,and then assay for cell viability.At the temperature(17±1)?,the grass carps were inoculated with the crude extract of 99% EGCG at 50 mg/kg and 100 mg/kg respectively.Then detected the activities of malondialdehyde(MDA),glutathione(GSH)and lysozyme(LZM)in the plasma of grass carp.The results showed that after EGCG was incubated with four cells,the cell viability remained between 80% and 97%,indicating that the three crude extracts of EGCG had no obvious toxic effects on fish cell lines.With the increase of intraperitoneal injection of EGCG,MDA in the plasma of grass carp showed a downward trend,and the contents of GSH and LZM increased,indicating that the crude EGCG extract can protect the health of fish by reducing the peroxidation reaction in fish.3.EGCG is easily absorbed and metabolized in grass carp,Gobiocypris rarus and Penaeus vannameiUnder the condition of water temperature(17±1)?,grass carp were injected intraperitoneally with a crude extract of 99% EGCG at a concentration of 150 mg/kg,and Gobiocypris rarus was injected intraperitoneally at(22±1)?,and the Penaeus vannamei was intramuscularly injected.Sampling at multiple time points,using liquid chromatograsph/mass spectrometer to detect EGCG content in tissues,The pharmacokinetic parameters of EGCG in various tissues after drug administration were estimated by the statistical distance principle.The results showed that at(17±1)?,the peak time of EGCG in the kidney and blood of grass carp was 12 h,and the peak concentrations were 1630.9 ng/mL and 20924.1 ng/mL.After 48 h,the EGCG contents in the kidney and blood of grass carp were 2.087 ng/mL and 0.503 ng/mL.At(22±1)?,the peak time of EGCG in Gobiocypris rarus muscle was 2h,the peak concentration was 5.004 ?g/mL,and the peak time in muscle and hepatopancreas of Penaeus vannamei was 0.5 h,the peak concentrations were 41.0529 ?g/mL and 2.825 ?g/mL.After 24 h,the EGCG content in the Gobiocypris rarus muscle was 0.014 ?g/mL,and the EGCG contents in the muscle and hepatopancreas of Penaeus vannamei were 0.912 ?g/mL and 0.162 ?g/mL.The results of this study indicate that the absorption of EGCG in organisms is greatly affected by temperature and biological species,which provides a scientific basis for the later use of EGCG to control grass carp hemorrhage and prawn white spot syndrome.