• Biomedical Science Letters
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• v.16 no.4
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• pp.229-238
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• 2010

Chicken Mx protein (cMx) induced interferon (IFN) is an antiviral protein to inhibit replication of RNA virus, particularly negative stranded RNA virus, through blockage of transfortation of viral RNA and proteins. In order to determine antiviral effects of cMx from different MHC haplotype chicken, we characterized cMx gene by studying on nucleotide sequencing, antiviral effects to Newcastle disease virus, VSV and MDV, and transcription activities. Three types of eMx genes (2,118 bp) were detected from the different MHC haplotype chickens [B19 (N), B15(F) and B21 (GSP)] chickens, which have showed different susceptible to Marek's disease (MD). Several amino acid substitutions were showed in the cMx. The amino acid 548 and 631 in the cMxs from N and F, chickens susceptible to MD, was Val and Asn which was important on antiviral effects, and showed in resistant cMx. Those in the cMx from GSP, chicken resistant to MD, were same that showed in susceptible cMx. Though every cMx transactivated the expression of the reporter gene, the transcription activation by resistant cMx from N and F was lower compared to that by susceptible cMx from GSP. The decease of the cell growth in the resistant cMx cloned cells was seen in comparison with another cMx clone cells. Replication of NDV and VSV was suppressed in the clones with resistant cMx from N and F. NMx258-transducted cells lack of antiviral effects, and NMx437 or NMx646-transducted cells was showed 60% of antiviral effects compared to NMx705. Mean death time (MDT) and hemaggutination (HA) titer to NDV was long and low in the eggs of N and F lines, but short and high in the egg of GSP line. Interestingly, strong suppression to NDV was observed in the clone with N-Mx and in the eggs of N line. However, the effects of Mx for replication of vvMDV1 have not been. Thus, resistant types of cMx, N- and F-Mx, have showed the anti-viral effects to only RNA virus including NDV and VSV, but not to DNA virus. Antiviral effects of cMx were required whole length of amino acid including Val and Asn in amino acid 548 and 631.

• Journal of fish pathology
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• v.35 no.1
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• pp.41-46
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• 2022

Since viral haemorrhagic septicaemia virus (VHSV) was first reported in European rainbow trout (Oncorhynchus mykiss) in the 1930s, it has caused high prices in freshwater and saltwater fish around the world, causing enormous economic damage to the aquaculture industry. We have been seeking required countermeasures against viruses because of economic damage to the aquaculture industry. However, commercial vaccines have the limitations of being costly to use in farms and being effective to only one pathogen. The aquaculture industry these days is taking on new alternatives to vaccines, antibiotics and chemicals. In this study, the suitability of antiviral effects against VHSV was evaluated in vitro for various plant extracts to judge their effectiveness. Atriplex gmelinii, Ixeris repens, Arctium lappa, and Sargassum coreanum were tested to know the correlation between the amount of virus and the concentration of extract investigates if these extracts have antiviral effects. Virus and extracts at various concentrations were inoculated simultaneously as 1:1 ratio into EPC cell lines. There are no antiviral effects with Atriplex gmelinii, Ixeris repens and Arctium lappa. Extract of Sargassum coreanum only has the antiviral activity in a dose-dependent manner. These results show that extract of Sargassum coreanum can be used in aquaculture industry as an antiviral materials.

• Journal of Veterinary Science
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• v.21 no.5
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• pp.72.1-72.10
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• 2020

Background: Fenbendazole, a dewormer drug, is used widely in the clinical treatment of parasite infections in animals. Recent studies have shown that fenbendazole has substantial effects on tumor growth, immune responses, and inflammatory responses, suggesting that fenbendazole is a pluripotent drug. Nevertheless, the antiviral effects have not been reported. Fenbendazole can disrupt microtubules, which are essential for multiple viruses infections, suggesting that fenbendazole might have antiviral effects. Objectives: This study examined whether fenbendazole could inhibit bovine herpesvirus 1 (BoHV-1) productive infection in cell cultures. Methods: The effects of fenbendazole on viral production, transcription of the immediate early (IE) genes, viron-associated protein expression, and the cellular signaling PLC-γ1/Akt pathway were assessed using distinct methods. Results: Fenbendazole could inhibit BoHV-1 productive infections significantly in MDBK cells in a dose-dependent manner. A time-of-addition assay indicated that fenbendazole affected both the early and late stages in the virus replication cycles. The transcription of IE genes, including BoHV-1 infected cell protein 0 (bICP0), bICP4, and bICP22, as well as the synthesis of viron-associated proteins, were disrupted differentially by the fenbendazole treatment. The treatment did not affect the cellular signaling pathway of PLC-γ1/Akt, a known cascade playing important roles in virus infection. Conclusions: Overall, fenbendazole has antiviral effects on BoHV-1 replication.

• Journal of Veterinary Science
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• v.19 no.6
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• pp.788-797
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• 2018

In many countries, vaccines are used for the prevention of foot-and-mouth disease (FMD). However, because there is no protection against FMD immediately after vaccination, research and development on antiviral agents is being conducted to induce protection until immunological competence is produced. This study tested whether well-known chemicals used as RNA virus treatment agents had inhibitory effects on FMD viruses (FMDVs) and demonstrated that ribavirin showed antiviral effects against FMDV in vitro/in vivo. In addition, it was observed that combining the administration of the antiviral agents orally and complementary therapy with vaccines synergistically enhanced antiviral activity and preserved the survival rate and body weight in the experimental animals. Antiviral agents mixed with an adjuvant were inoculated intramuscularly along with the vaccines, thereby inhibiting virus replication after injection and verifying that it was possible to induce early protection against viral infection prior to immunity being achieved through the vaccine. Finally, pigs treated with antiviral agents and vaccines showed no clinical signs and had low virus excretion. Based on these results, it is expected that this combined approach could be a therapeutic and preventive treatment for early protection against FMD.

• Journal of Ginseng Research
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• v.35 no.4
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• pp.429-435
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• 2011

Korean red ginseng has been studied various biological activities such as immune, anti-oxidative, anti-microbial, and anticancer activities but antiviral mechanism needs further studies. In this study, we aimed to examine the antiviral effects of Korea red ginseng extract and ginsenosides on norovirus surrogate, including murine norovirus (MNV) and feline calicivirus (FCV). We evaluated the pre-, co-, and post-treatment effects of Korean red ginseng (KRG), ginsenosides $Rb_1$ and $Rg_1$. To measure the antiviral effect and cytotoxicity of KRG extract, and ginsenosides $Rb_1$ and $Rg_1$, we treated Crandell-Reese Feline Kidney for FCV or RAW264.7 cells for MNV with concentrations of 0, 5, 6.7, 10, 20 ug/mL total saponin. There was cytotoxic effect in the highest concentration 20 ug/mL of KRG extract so this concentration was excluded in this study. The FCV titer was significantly reduced to 0.23-0.83 $log_{10}$ 50% tissue culture infectious dose ($TCID_{50}$)/mL in groups pre-treated with red ginseng extract or ginsenosides. The titer of MNV was significantly reduced to 0.37-1.48 $log_{10}$ $TCID_{50}$/mL in groups pre-treated with red ginseng extract or ginsenosides. However, there was no observed antiviral effect in groups co-treated or post-treated with KRG and its constituents. Our data suggest that KRG extract has an antiviral effect against norovirus surrogates. The antiviral mechanisms of KRG and ginsenosides should be addressed in future studies.

• Journal of Microbiology and Biotechnology
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• v.30 no.2
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• pp.172-177
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• 2020

Influenza viruses cause respiratory diseases in humans and animals with high morbidity and mortality rates. Conventional anti-influenza drugs are reported to exert side effects and newly emerging viral strains tend to develop resistance to these commonly used agents. Fritillaria thunbergii (FT) is traditionally used as an expectorant for controlling airway inflammatory disorders. Here, we evaluated the therapeutic effects of FT extracts against influenza virus type A (H1N1) infection in vitro, in ovo, and in vivo. In the post-treatment assay, FT extracts showed high CC50 (7,500 ㎍/ml), indicating low toxicity, and exerted moderate antiviral effects compared to oseltamivir (SI 50.6 vs. 222) in vitro. Antiviral activity tests in ovo revealed strong inhibitory effects of both FT extract and oseltamivir against H1N1 replication in embryonated eggs. Notably, at a treatment concentration of 150 mg/kg, only half the group administered oseltamivir survived whereas the FT group showed 100% survival, clearly demonstrating the low toxicity of FT extracts. Consistent with these findings, FT-administered mice showed a higher survival rate with lower body weight reduction relative to the oseltamivir group upon treatment 24 h after viral infection. Our collective results suggest that FT extracts exert antiviral effects against influenza H1N1 virus without inducing toxicity in vitro, in ovo or in vivo, thereby supporting the potential utility of FT extract as a novel candidate therapeutic drug or supplement against influenza.

• Journal of Ginseng Research
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• v.47 no.2
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• pp.329-336
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• 2023

Background: Panax ginseng Meyer is a medicinal plant well-known for its antiviral activities against various viruses, but its antiviral effect on coronavirus has not yet been studied thoroughly. The antiviral activity of Korean Red Ginseng (KRG) and ten ginsenosides against Human coronavirus OC43 (HCoV-OC43) was investigated in vitro. Methods: The antiviral response and mechanism of action of KRG extract and ginsenoside Rc, Re, Rf, Rg1, Rg2-20 (R) and -20 (S), Rg3-20 (R) and -20 (S), and Rh2-20 (R) and -20 (S), against the human coronavirus strain OC43 were investigated by using plaque assay, time of addition assay, real-time PCR, and FACS analysis. Results: Virus plaque formation was reduced in KRG extract-treated and HCoV-OC43-infected HCT-8 cells. KRG extract decreased the viral proteins (Nucleocapsid protein and Spike protein) and mRNA (N and M gene) expression, while increased the expression of interferon genes. Conclusion: KRG extract exhibits antiviral activity by enhancing the expression of interferons and can be used in treating infections caused by HCoV-OC43.

• 한국생물공학회:학술대회논문집
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• 2003.04a
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• pp.615-620
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• 2003

The sulfated exopolysaccharide p-KG03, which is produced by the marine microalga Gyrodinium impudicum strain KG03, exhibited impressive antiviral activity in vitro ($EC_{50}$ = 26.9 g/ml) against the encephalomyocarditis virus (EMCV). Depending on the p-KG03 concentration, the development of cytopathic effects in EMCV-infected HeLa cells was either inhibited completely or slowed. Moreover, p-KG03 did not show any cytotoxic effects on HeLa cells, even at concentrations up to 1,000 g/ml. The polysaccharide was purified by repeated precipitation in ethanol, followed by gel filtration. The p-KG03 polysaccharide had a molecular weight of $1.87\;{\times}\;10^6$, and was characterized as a homopolysaccharide of galactose with uronic acid (2.96%, w/w) and sulfate groups (10.32% w/w). The biological activities of p-KG03 suggest that sulfated metabolites from marine organisms are a rich source of antiviral agents. This is the first reported marine source of antiviral sulfated polysaccharides against EMCV. The p-KG03 polysaccharide may be useful for the development of marine bioactive exopolysaccharides for use in biotechnological and pharmaceutical products.

• YAKHAK HOEJI
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• v.39 no.6
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• pp.622-630
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• 1995

Inoculation of Friend anemia virus, which was a Kind of retro virus such as HIV, results splenomegaly, anemia, the increase of WBC counts and reverse transcriptase activity in serum. These results were due to the inhibition of the differentiation of erythroid progenitor cell by the FVA at the spleen. Using these as index of antiviral effects, we pursued the establishment of in vivo screening method for the new anti-ADS drugs. Among zidovudine, didanosine and zalcitabine, which were already approved as anti-AIDS drugs, treatment of zidovudine for 18 days in BALB/c mice inoculated with Friend anemia virus resulted the most potent inhibitory effects on the splenomegaly, the increase of WBC counts and reverse transcriptase activity, but did not recovered the anemia due to the tomcity of zidovudhie itself on the bone marrow. The antiviral effects of zidovudine was reduced in case of zidovudine treatment 7 days after Friend anemia virus inoculation. These results suggested that the sooner treatment of zidovudine would be better improved when the virus was inoculated. Human recombinant interferon itself .alpha. did not showed the antiviral activity against Friend anemia virus and did not also affected the antiviral activity of zidovudine. These results suggested that Friend anemia virus would be used as a tool in vivo screening method for the Lobster of reverse transcriptase.

• Journal of Life Science
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• v.32 no.5
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• pp.375-390
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• 2022

Influenza viruses are zoonotic respiratory pathogens, and influenza infections have caused a substantial burden on public health systems and the livestock industry. Although currently approved seasonal influenza vaccines have shown potent protection efficacy against antigenically well-matched strains, there are considerable unmet needs for the efficient control of viral infections. Enormous efforts have been made to develop broadly protective universal influenza vaccines to tackle the huge levels of genetic diversity and variability of influenza viruses. In addition, antiviral drugs have been considered important interventions for the treatment of viral infections. The viral neuraminidase inhibitor oseltamivir is the most widely used antiviral medication to treat influenza A and influenza B viruses. However, unsatisfactory clinical outcomes resulting from side effects and the emergence of resistant variants have led to greater attention being paid to plants as a natural resource for anti-influenza drugs. In particular, the recent COVID-19 pandemic has underpinned the need for safe and effective antiviral drugs with a broad spectrum of antiviral activity to prevent the rapid spread of viruses among humans. This review outlines the results of the antiviral activities of various natural products isolated from plants against influenza viruses. Special focus is paid to the virucidal effects and the immune-enhancing effects of antiviral natural products, since the products have broad applications as inactivating agents for the preparation of inactivated vaccines and vaccine adjuvants.