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...
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.
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.
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제안 방법
Influenza infection causes a cytopathic effect (CPE) that is signified by the cellular detachment as well as the cell rounding, swelling, and finally death [6, 21]. In order to evaluate the effect of the three selected extracts on the CPE of the infected cells, the CPE reduction assay was performed. The MDCK cells were first infected with the influenza virus and treated with the plant extracts at the concentration of 100 µg/ml.
In this study, three thousand plant extracts were investigated for their antiviral effects against influenza virus infection using the cell-based screening system. We found three plant extracts that could inhibit the infection by the influenza A/PR/8/34 virus in the cell culture.
The PCR was performed for 25 cycles at the following times and temperatures:10 s at 94ºC, 30 s at 55ºC, 1 min at 68ºC, and 5 min at 68ºC.
After 3 days of incubation, the antiviral activity was determined by the cell viability assay as described above. The plates were then examined by photometric analysis for the cytopathic effect. The cell morphology was observed under the inverted microscope at 10 × 20 magnification.
To find the plant extracts that have antiviral effects, we performed the cell-based screening and measured ATP levels to determine the viability of the cell. MDCK cells were infected with influenza A/PR/8/34 virus with or without 100 µg/ml of plant extract.
대상 데이터
The cells were incubated in a humidified atmosphere of 5% CO2 at 37ºC. Oseltamivir carboxylate, the active form of oseltamivir, was provided by Chungnam National University Hospital.
The primer sequences were as follows: 5'-AGTGAGCGAGGACTGCAGCGT-3' and 5'-TAGCYT TAGCYGTRGTGCTGGC-3' for the M gene, 5'-CCCATCACCATC TTCCAGGAGC-3' and 5'-CCAGTGAGCTTCCCTTCAGC-3' for the GAPDH gene.
성능/효과
Among the tested extracts, three plant extracts – Thuja orientalis, Aster spathulifolius, and Pinus thunbergii – had the highest percentages of viable cells at 77.3%, 76.8%, and 76.7%, respectively (Table 1).
3E, 3F). The microscopic evaluation suggested that T. orientalis, A. spathulifolius, and P. thunbergii had protective effects against the PR8 virus infection at 48 hpi. Considering these results, the inhibitory activity of the plant extracts against the virus-induced cell death can be thought to be roughly correlated with the cell viability assay described earlier (Fig.
This study suggests that if a single component that has anti-influenza activity is identified from the T. orientalis extract, it might have a great potential to be used as an effective agent for the treatment of influenza virus infections. We will alsºConduct more studies to evaluate whether these treatments can result in the antiviral activity in animals.
후속연구
orientalis and suggest that the infection prevention mechanism of the plant extract might involve the blockage of the virus attachment to the host cells or the inhibition of the virus replication. However, further studies are needed to determine the exact inhibitory mechanism of the plant extract.
1). The isolated plant extracts might show the antiviral activity by increasing the viability of the influenza virus-infected cells, but further investigations are required to make a definite conclusion.
orientalis extract, it might have a great potential to be used as an effective agent for the treatment of influenza virus infections. We will alsºConduct more studies to evaluate whether these treatments can result in the antiviral activity in animals.
참고문헌 (25)
Bright, R. A., D. K. Shay, B. Shu, N. J. Cox, and A. I. Klimov. 2006. Adamantane resistance among influenza A viruses isolated early during the 2005-2006 influenza season in the United States. JAMA 295: 891-894.
Cassetti, M. C., R. Couch, J. Wood, and Y. Pervikov. 2005. Report of meeting on the development of influenza vaccines with broad spectrum and long-lasting immune responses, World Health Organization, Geneva, Switzerland, 26-27 February 2004. Vaccine 23: 1529-1533.
CDC. 2009. Effectiveness of 2008-09 trivalent influenza vaccine against 2009 pandemic influenza A (H1N1) - United States, May-June 2009. Morb. Mortal. Wkly. Rep. 58.
Choi, H. J., J. H. Song, K. S. Park, and D. H. Kwon. 2009. Inhibitory effects of quercetin 3-rhamnoside on influenza A virus replication. Eur. J. Pharm. Sci. 37: 329-333.
Chomczynski, P. and N. Sacchi. 1987. Single-step method of RNA isolation by acid guanidinium thiocyanate-phenolchloroform extraction. Anal. Biochem. 162: 156-159.
Condit, R. C. 2006. Fields virology, pp. 25-57. In D. M. Knipe and P. M. Howley (eds.). Principles of Virology, 5th Ed. Lippincott Williams and Wilkins, Philadelphia.
Couch, R. B. and G. G. Jackson. 1976. Antiviral agents in influenza - summary of Influenza Workshop VIII. J. Infect. Dis. 134: 516-527.
Furuta, Y., K. Takahashi, M. Kuno-Maekawa, H. Sangawa, S. Uehara, K. Kozaki, et al. 2005. Mechanism of action of T-705 against influenza virus. Antimicrob. Agents Chemother. 49: 981-986.
Garten, R. J., C. T. Davis, C. A. Russell, B. Shu, S. Lindstrom, A. Balish, et al. 2009. Antigenic and genetic characteristics of swine-origin 2009 A(H1N1) influenza viruses circulating in humans. Science 325: 197-201.
Hampson, A. W. 2002. Influenza virus antigens and 'antigenic drift', pp. 49-85. In C. W. Potter (ed.). Perspectives in Medical Virology, Vol. 7. Elsevier.
Hui, E. K. and D. P. Nayak. 2001. Role of ATP in influenza virus budding. Virology 290: 329-341.
Irvine, J. D., L. Takahashi, K. Lockhart, J. Cheong, J. W. Tolan, H. E. Selick, and J. R. Grove. 1999. MDCK (Madin-Darby canine kidney) cells: A tool for membrane permeability screening. J. Pharm. Sci. 88: 28-33.
Jackson, D. C. and L. E. Brown. 1991. A synthetic peptide of influenza virus hemagglutinin as a model antigen and immunogen. Pept. Res. 4: 114-124.
Kawaoka, Y. 2006. Influenza Virology: Current Topics. Caister Academic Press.
Kelly, H. and K. Grant. 2009. Interim analysis of pandemic influenza (H1N1) 2009 in Australia: Surveillance trends, age of infection and effectiveness of seasonal vaccination. Euro. Surveill. 14.
Kiso, M., K. Takahashi, Y. Sakai-Tagawa, K. Shinya, S. Sakabe, Q. M. Le, et al. 2010. T-705 (favipiravir) activity against lethal H5N1 influenza A viruses. Proc. Natl. Acad. Sci. USA 107: 882-887.
Murris-Espin, M., A. Didier, S. Mezghani, L. Lacassagne, and P. Leophonte. 1999. Influenza and asthma. Rev. Mal. Res. 16: 9-15.
Noah, J. W., W. Severson, D. L. Noah, L. Rasmussen, E. L. White, and C. B. Jonsson. 2007. A cell-based luminescence assay is effective for high-throughput screening of potential influenza antivirals. Antiviral Res. 73: 50-59.
Numazaki, Y., T. Oshima, A. Ohmi, A. Tanaka, Y. Oizumi, S. Komatsu, et al. 1987. A microplate method for isolation of viruses from infants and children with acute respiratory infections. Microbiol. Immunol. 31: 1085-1095.
Palese, S. M. 2007. Orthomyxoviridae: The viruses and their replication, pp. 1647-1689. In K. DM and H. PM (eds.). Fields Virology, 5th Ed. Lippincott Williams &Wilkins, Philadelphia.
Poland, G. A., R. M. Jacobson, and P. V. Targonski. 2007. Avian and pandemic influenza: An overview. Vaccine 25: 3057-3061.
Renaud, C., J. Kuypers, and J. A. Englund. 2011. Emerging oseltamivir resistance in seasonal and pandemic influenza A/ H1N1. J. Clin. Virol. 52: 70-78.
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