• Journal of Microbiology and Biotechnology
• /
• v.23 no.1
• /
• pp.125-130
• /
• 2013

Influenza viruses cause significant morbidity and mortality in humans through epidemics or pandemics. Currently, two classes of anti-influenza virus drugs, M2 ion-channel inhibitors (amantadin and rimantadine) and neuraminidase inhibitors (oseltamivir and zanamivir), have been used for the treatment of the influenza virus infection. Since the resistance to these drugs has been reported, the development of a new antiviral agent is necessary. In this study, we examined the antiviral efficacy of the plant extracts against the influenza A/PR/8/34 infection. In vitro, the antiviral activities of the plant extracts were investigated using the cell-based screening. Three plant extracts, Thuja orientalis, Aster spathulifolius, and Pinus thunbergii, were shown to induce a high cell viability rate after the infection with the influenza A/PR/8/34 virus. The antiviral activity of the plant extracts also increased as a function of the concentration of the extracts and these extracts significantly reduced the visible cytopathic effect caused by virus infections. Furthermore, the treatment with T. orientalis was shown to have a stronger inhibitory effect than that with A. spathulifolius or P. thunbergii. These results may suggest that T. orientalis has anti-influenza A/PR/8/34 activity.

• Journal of fish pathology
• /
• v.16 no.3
• /
• pp.139-146
• /
• 2003

We have investigated the biological effects of recombinant IL-1$\beta$ (rIL-1$\beta$) on the expression of antiviral genes such as Myxovirus-3 (MX-3) and Interferon regulating factor-1 (IRF-1), which are related to type I interferon. When ten micrograms of rIL-1$\beta$ were treated, we observed the stimulatory effect on the expression of these antiviral genes. Interestingly, at the early stage of stimulation, these genes were down-regulated and then up-regulated by the results obtained that the expressions of these genes were decreased at day 1 post-injection and gradually increased at day 3 post-injection. Thus, the stimulatory effect of rIL-1$\beta$ on the expression of MX-3 and IRF-3 gene might be an indirect stimulatory effect because significant up-regulation was delayed until day 3 post-injection.

• Korean Journal of Pharmacognosy
• /
• v.47 no.2
• /
• pp.137-142
• /
• 2016

Enterovirus is a common cause of several severe diseases such as myocarditis, hand-foot-mouth disease, and meningitis in children and adult. There are many try to develop new antiviral drug for direct treatment in virus infection. However, synthetic chemical antiviral drug is not working. To overcome this limitation, we examined plant extracts. The antiviral effect of plant extracts was screened by HeLa cell survival assay in coxsackievirus B3 (CVB3) infection. We observed a strong antiviral effect of Poria cocos extract in a dose-dependent manner (1 mg/ml~0.01 mg/ml). P. cocos extract (1 mg/ml) treatment was dramatically decreased virus protease 2A induced eIF4G-I cleavage and virus capsid protein VP1 production. CVB3 positive and negative strand RNA amplification were significantly reduced in P. cocos extract treatment. P. cocos extract completely blocked early time activation of ERK and AKT activity in CVB3 infection. Taken together these data indicate that the treatment of P. cocos extract strongly inhibit CVB3 replication. Poria cocos extract may possible to developed as a therapeutic agent for enterovirus.

• YAKHAK HOEJI
• /
• v.49 no.2
• /
• pp.151-155
• /
• 2005

For decades, the demand for new antiviral strategies, especially in hepatitis, has increased markedly due to its devastating pathogenic outcome, In the present study, we examin ed the antiviral effect of the combination of amantadine and biphenyl dimethyl dicarboxylate (DDB) in HepG2 2.2.15, which is transfected with HBV DNA. The study demonstrated that the combination not the single treatment may have an anti-HBV effect through a synergism of antiviral, anti-inflammatory and cytoprotective activities in STAT1 ${\alpha}$, 6-16 gene, and pro-inflammatory components such as nitric oxide and IL-1${\beta}$ expression. In addition, hepatitis B surface and core gene expression were examined as a final end point for the anti-HBV activities, which was also significantly suppressed comparing to normal control (p<0.01).

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

• Archives of Pharmacal Research
• /
• v.15 no.3
• /
• pp.242-245
• /
• 1992

Two triterpenes 1 and 2 with antiviral activity against Herpes simplex virus type 1 in vitro were isolated from Prunella vulgaris. Each compound caused a significant reduction in viral cytopathic effect when vero cells were exposed to them for 72 hours after viral challenge. They were identified as betulinic acid (1) and $2\alpha, 3\alpha$-dihydroxyurs-12-en-28-oic acid(2) on the basis of their spectroscopic properties. The antiviral activity of them was estimated as $EC_{50}=30\;\mu$g/ml(1) and $8\;\mu$g/ml(2), respectively by plaque reduction assay.

• Korean Journal of Pharmacognosy
• /
• v.30 no.3
• /
• pp.244-249
• /
• 1999

In order to find less toxic antiviral agents from Basidiomycetes, EA, the water soluble substance, was prepared from the carpophores of Elfvingia applanata(Pers.) Karst. Antiviral activity of EA against vesicular stomatitis virus [Indiana serotype, VSV(IND)] was examined in Vero cells using plaque reduction assay in vitro. And the combined antiviral effects of EA with interferon (IFN) alpha or gamma were examined on the multiplication of VSV(IND). EA caused a concentration-dependent reduction in the plaque formation of VSV(IND) with 50% effective concentration $(EC_{50})$ of $104.02\;{\mu}g/ml$. The results of combination assay were evaluated by the combination index (CI) that was analysed by the multiple drug effect analysis. All cases of the combination of EA with IFN alpha or IFN gamma showed potent synergism with CI values of $0.38{\sim}0.52$ for $50{\sim}90%$ effective levels.

• Microbiology and Biotechnology Letters
• /
• v.42 no.2
• /
• pp.207-210
• /
• 2014

Viral infections are capable of inducing reactive oxygen species (ROS) production in the infected cells and antioxidants have been reported to have antiviral activities against many viruses. In this study, an antiviral assay using the cytopathic effect (CPE) reduction method revealed that gallic acid possesses good anti-coxsackievirus B3 (CB3) and coxsackievirus B4 (CB4) activities, reducing the formation of visible CPE. However, ribavirin did exhibit weak anti-CB3 and CB4 activities and was unable to prevent CPE. Therefore, we conclude that the inhibition of CB3 or CB4 production by gallic acid may be due to its general action as an antioxidant.

• Korean Journal Plant Pathology
• /
• v.13 no.1
• /
• pp.63-68
• /
• 1997

In the screening of antiviral materials produced by actinomycetes, an isolate named B25 was fond to produce an antibiotic substance ASA, which showed a strong inhibitory activity against tobacco mosaic virus (TMV) infection. ASA was purified from culture broth of B25 by silica gel column chromatography, preparative TLC, and reversed phase HPLC. Also MS, IR, UV spectrum, and melting point of ASA were determined and analysed. ASA was white powder soluble in dimethyl sulfoxide, chloroform, and ethyl acetate, having absorption peaks at 223 and 328 nm in UV-VIS spectrum, and had a molecular weight of 548. ASA showed strong inhibitory effect on TMV infection when it was applied as a mixture of TMV to the upper surface of leaves of a local lesion host (Nicotiana tabacum c. Xanthi-nc). It also showed antimicrobial effect against yeast and some phytopathogenic fungi.

• Archives of Pharmacal Research
• /
• v.24 no.1
• /
• pp.74-78
• /
• 2001

A preparation of water soluble components (EA) was made from carpophores of Elfvingia applanata (Pers.) Karst and its in vitro antiviral activity on vesicular stomatitis virus [(Indiana serotype, VSV(IND)] was investigated by plaque reduction assay. EA exhibited potent antiviral activity on VSV(IND) growth and negligible cytotoxicity on Vero cells, 50% effective concentration ($EC_{50}C$/) of 104$ug\textrm\/ml$ and 50% cytotoxic concentration ($CC_{50}C$) of 3,793$ug\textrm\/ml$, respectively. Selectivity index (Sl $CC_{50}C$/$EC_{50}C$) of EA on Vero cell and VSV(IND) was about 36.5. EA did not display either a direct virucidal effect on V5V(IND) or induction of antiviral substance by Vero cells upon its treatment. Thus, the mode of antiviral activity of EA was studied at steps of viral adsorption onto cell. When both EA and virus were added to cell monolayers, titer of cell-free virus in culture supernatant increased in ca. 30-40% compared with that of control group and titer of cell-associated virus was 60-100% higher than that of control group. These results suggested that antiviral activity of EA on VSV(IND) might be due to the hindrance of viral entry to cells at eITher endocytosis or loss of envelope.