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Sample records for high antiviral activity

  1. Broad spectrum antiviral activity of favipiravir (T-705: protection from highly lethal inhalational Rift Valley Fever.

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    Amy L Caroline

    2014-04-01

    Full Text Available BACKGROUND: Development of antiviral drugs that have broad-spectrum activity against a number of viral infections would be of significant benefit. Due to the evolution of resistance to currently licensed antiviral drugs, development of novel anti-influenza drugs is in progress, including Favipiravir (T-705, which is currently in human clinical trials. T-705 displays broad-spectrum in vitro activity against a number of viruses, including Rift Valley Fever virus (RVFV. RVF is an important neglected tropical disease that causes human, agricultural, and economic losses in endemic regions. RVF has the capacity to emerge in new locations and also presents a potential bioterrorism threat. In the current study, the in vivo efficacy of T-705 was evaluated in Wistar-Furth rats infected with the virulent ZH501 strain of RVFV by the aerosol route. METHODOLOGY/PRINCIPAL FINDINGS: Wistar-Furth rats are highly susceptible to a rapidly lethal disease after parenteral or inhalational exposure to the pathogenic ZH501 strain of RVFV. In the current study, two experiments were performed: a dose-determination study and a delayed-treatment study. In both experiments, all untreated control rats succumbed to disease. Out of 72 total rats infected with RVFV and treated with T-705, only 6 succumbed to disease. The remaining 66 rats (92% survived lethal infection with no significant weight loss or fever. The 6 treated rats that succumbed survived significantly longer before succumbing to encephalitic disease. CONCLUSIONS/SIGNIFICANCE: Currently, there are no licensed antiviral drugs for treating RVF. Here, T-705 showed remarkable efficacy in a highly lethal rat model of Rift Valley Fever, even when given up to 48 hours post-infection. This is the first study to show protection of rats infected with the pathogenic ZH501 strain of RVFV. Our data suggest that T-705 has potential to be a broad-spectrum antiviral drug.

  2. In vitro evaluation of antiviral and virucidal activity of a high molecular weight hyaluronic acid

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    Blasi Elisabetta

    2011-03-01

    Full Text Available Abstract Background hyaluronic acid (HA, a non-sulphated glycosaminoglycan, is present in synovial fluid, vitreous humour serum and many connective tissues. Pharmaceutical preparations of HA are used in clinical practice for wound healing, joint pain, kerato-conjunctivitis, asthma, mouth care, oesophageal-reflux, and gastritis. Moreover, it is used as a filler to counteract ageing and facial lipoatrophy. Our study aims at investigating the in vitro antiviral activity of a high molecular weight HA. Methods the MTT test was used to rule out the potential toxic effects of HA on the different cell lines used in the antiviral assays. The antiviral activity of HA against Coxsackievirus B5, Herpes Simplex Virus-1, Mumps Virus, Adenovirus-5, Influenza Virus A/H1N1, Human Herpesvirus-6, Porcine Parvovirus, Porcine Reproductive and Respiratory Syndrome Virus was assessed by virus yield assays. Results the most effective inhibition was observed against Coxsackievirus B5, with 3Log reduction of the virus yield at 4 mg/ml, and a reduction of 3.5Log and 2Log, at 2 mg/ml and 1 mg/ml, respectively: the selectivity index was 16. Mumps virus was highly inhibited too showing a reduction of 1.7Log at 1 mg/ml and 1Log at 4 mg/ml and 2 mg/ml (selectivity index = 12. The selectivity index for Influenza Virus was 12 with the highest inhibition (1Log observed at 4 mg/ml. Herpes Simplex Virus-1 and Porcine Parvovirus were mildly inhibited, whereas no antiviral activity was observed with respect to Adenovirus-5, Human Herpesvirus-6, Porcine Reproductive and Respiratory Syndrome Virus. No HA virucidal activity was ever observed against any of the viruses tested. Kinetic experiments showed that both Coxsackievirus B5 and Herpes simplex virus-1 replication were consistently inhibited, not influenced by the time of HA addition, during the virus replication cycle. Conclusions the spectrum of the antiviral activity exhibited by HA against both RNA and DNA viruses, known to have

  3. Antiviral Drug Research Proposal Activity

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    Lisa Injaian

    2011-03-01

    Full Text Available The development of antiviral drugs provides an excellent example of how basic and clinical research must be used together in order to achieve the final goal of treating disease. A Research Oriented Learning Activity was designed to help students to better understand how basic and clinical research can be combined toward a common goal. Through this project students gained a better understanding of the process of scientific research and increased their information literacy in the field of virology. The students worked as teams to research the many aspects involved in the antiviral drug design process, with each student becoming an "expert" in one aspect of the project. The Antiviral Drug Research Proposal (ADRP culminated with students presenting their proposals to their peers and local virologists in a poster session. Assessment data showed increased student awareness and knowledge of the research process and the steps involved in the development of antiviral drugs as a result of this activity.

  4. Antiviral active peptide from oyster

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    An active peptide against herpes virus was isolated from the enzymic hydrolysate of oyster (Crassostrea gigas) and purified with the definite direction hydrolysis technique in the order of alcalase and bromelin. The hydrolysate was fractioned into four ranges of molecular weight (>10 kDa, 10-5 kDa, 5-1 kDa and <1 kDa) using ultrafiltration membranes and dialysis. The fraction of 10?5 kDa was purified using consecutive chromatographic methods including DEAE Sephadex A-25 column, Sephadex G-25 column, and high performance liquid chromatogram (HPLC) by activity-guided isolation. The antiviral effect of the obtained peptide on herpetic virus was investigated in Vero cells by observing cytopathic effect (CPE). The result shows that the peptide has high inhibitory activity on herpetic virus.

  5. Broad-Range Antiviral Activity of Hydrogen Sulfide Against Highly Pathogenic RNA Viruses

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    Bazhanov, Nikolay; Escaffre, Olivier; Freiberg, Alexander N.; Garofalo, Roberto P.; Casola, Antonella

    2017-01-01

    Hydrogen sulfide is an important endogenous mediator that has been the focus of intense investigation in the past few years, leading to the discovery of its role in vasoactive, cytoprotective and anti-inflammatory responses. Recently, we made a critical observation that H2S also has a protective role in paramyxovirus infection by modulating inflammatory responses and viral replication. In this study we tested the antiviral and anti-inflammatory activity of the H2S slow-releasing donor GYY4137 on enveloped RNA viruses from Ortho-, Filo-, Flavi- and Bunyavirus families, for which there is no FDA-approved vaccine or therapeutic available, with the exception of influenza. We found that GYY4137 significantly reduced replication of all tested viruses. In a model of influenza infection, GYY4137 treatment was associated with decreased expression of viral proteins and mRNA, suggesting inhibition of an early step of replication. The antiviral activity coincided with the decrease of viral-induced pro-inflammatory mediators and viral-induced nuclear translocation of transcription factors from Nuclear Factor (NF)-kB and Interferon Regulatory Factor families. In conclusion, increasing cellular H2S is associated with significant antiviral activity against a broad range of emerging enveloped RNA viruses, and should be further explored as potential therapeutic approach in relevant preclinical models of viral infections. PMID:28106111

  6. A critical subset model provides a conceptual basis for the high antiviral activity of major HIV drugs.

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    Shen, Lin; Rabi, S Alireza; Sedaghat, Ahmad R; Shan, Liang; Lai, Jun; Xing, Sifei; Siliciano, Robert F

    2011-07-13

    Control of HIV-1 replication was first achieved with regimens that included a nonnucleoside reverse transcriptase inhibitor (NNRTI) or a protease inhibitor (PI); however, an explanation for the high antiviral activity of these drugs has been lacking. Indeed, conventional pharmacodynamic measures like IC(50) (drug concentration causing 50% inhibition) do not differentiate NNRTIs and PIs from less active nucleoside reverse transcriptase inhibitors (NRTIs). Drug inhibitory potential depends on the slope of the dose-response curve (m), which represents how inhibition increases as a function of increasing drug concentration and is related to the Hill coefficient, a measure of intramolecular cooperativity in ligand binding to a multivalent receptor. Although NNRTIs and PIs bind univalent targets, they unexpectedly exhibit cooperative dose-response curves (m > 1). We show that this cooperative inhibition can be explained by a model in which infectivity requires participation of multiple copies of a drug target in an individual life cycle stage. A critical subset of these target molecules must be in the unbound state. Consistent with experimental observations, this model predicts m > 1 for NNRTIs and PIs and m = 1 in situations where a single drug target/virus mediates a step in the life cycle, as is the case with NRTIs and integrase strand transfer inhibitors. This model was tested experimentally by modulating the number of functional drug targets per virus, and dose-response curves for modulated virus populations fit model predictions. This model explains the high antiviral activity of two drug classes important for successful HIV-1 treatment and defines a characteristic of good targets for antiviral drugs in general, namely, intermolecular cooperativity.

  7. Naphthyridines with Antiviral Activity - A Review.

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    Singh, Inder P; Kumar, Sanjay; Gupta, Shiv

    2017-01-01

    Naphthyridine scaffold is an important pharmacophore in compounds which have shown various biological activities like antiviral, antimicrobial, anticancer, antiinflammatory and analgesic. This scaffold is also reported to exhibit activity against HIV, HCMV, HSV, HPV and HCV. Antiviral activity displayed by many naphthyridine analogs is in nM range. Only few review articles are available in literature which describe about various biological activities of naphthyridines, but there is no comprehensive compilation particularly for antiviral activities. The objective of this review is to compile the literature on anti-viral activities of naphthyridine analogs. SciFinder, Google Scholar and PubMed database were searched with keyword "naphthyridine" and the references obtained were further sorted using keywords "antihiv", "antiviral" and "virus", separately. References obtained were considered to review the antiviral literature of naphthyridines. Literature search using SciFinder database with different keywords gave several references. Only references of antiviral activities of naphthyridine compounds were reviewed. References to in-silico studies alone or on formulation development or on patents were excluded. This review will be helpful for future researches to design and synthesize naphthyridine analogs with improved antiviral activities. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  8. Antiviral activity of ovotransferrin derived peptides.

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    Giansanti, Francesco; Massucci, M Teresa; Giardi, M Federica; Nozza, Fabrizio; Pulsinelli, Emy; Nicolini, Claudio; Botti, Dario; Antonini, Giovanni

    2005-05-27

    Ovotransferrin and lactoferrin are iron-binding proteins with antiviral and antibacterial activities related to natural immunity, showing marked sequence and structural homologies. The antiviral activity of two hen ovotransferrin fragments DQKDEYELL (hOtrf(219-227)) and KDLLFK (hOtrf(269-301) and hOtrf(633-638)) towards Marek's disease virus infection of chicken embryo fibroblasts is reported here. These fragments have sequence homology with two bovine lactoferrin fragments with antiviral activity towards herpes simplex virus, suggesting that these fragments could have a role for the exploitation of the antiviral activity of the intact proteins towards herpes viruses. NMR analysis showed that these peptides, chemically synthetized, did not possess any favourite conformation in solution, indicating that both the aminoacid sequence and the conformation they display in the intact protein are essential for the antiviral activity.

  9. Antiviral activities of heated dolomite powder.

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    Motoike, Koichi; Hirano, Shozo; Yamana, Hideaki; Onda, Tetsuhiko; Maeda, Takayoshi; Ito, Toshihiro; Hayakawa, Motozo

    2008-12-01

    The effect of the heating conditions of dolomite powder on its antiviral activity was studied against the H5N3 avian influenza virus. Calcium oxide (CaO) and magnesium oxide (MgO), obtained by the thermal decomposition of dolomite above 800 degrees C, were shown to have strong antiviral activity, but the effect was lessened when the heating temperature exceeded 1400 degrees C. Simultaneous measurement of the crystallite size suggested that the weakening of the activity was due to the considerable grain growth of the oxides. It was found that the presence of Mg in dolomite contributed to the deterrence of grain growth of the oxides during the heating process. Although both CaO and MgO exhibited strong antiviral activity, CaO had the stronger activity but quickly hydrated in the presence of water. On the other hand, the hydration of MgO took place gradually under the same conditions. Separate measurements using MgO and Mg(OH)2 revealed that MgO had a higher antiviral effect than Mg(OH)2. From the overall experiments, it was suggested that the strong antiviral activity of dolomite was related to the hydration reaction of CaO.

  10. A cell-penetrating antibody fragment against HIV-1 Rev has high antiviral activity: characterization of the paratope.

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    Zhuang, Xiaolei; Stahl, Stephen J; Watts, Norman R; DiMattia, Michael A; Steven, Alasdair C; Wingfield, Paul T

    2014-07-18

    The HIV-1 protein Rev oligomerizes on viral transcripts and directs their nuclear export. Previously, a Fab against Rev generated by phage display was used to crystallize and solve the structure of the Rev oligomerization domain. Here we have investigated the capability of this Fab to block Rev oligomerization and inhibit HIV-1 replication. The Fab itself did not have antiviral activity, but when a Tat-derived cell-penetrating peptide was appended, the resulting molecule (FabRev1-Tat) was strongly inhibitory of three different CCR5-tropic HIV-1 isolates (IC50 = 0.09-0.44 μg/ml), as assessed by suppression of reverse transcriptase activity in infected peripheral blood mononuclear cells, and had low cell toxicity (TC50 > 100 μg/ml). FabRev1-Tat was taken up by both peripheral blood mononuclear and HEK293T cells, appearing in both the cytoplasm and nucleus, as shown by immunofluorescence confocal laser scanning microscopy. Computational alanine scanning was used to identify key residues in the complementarity-determining regions to guide mutagenesis experiments. Residues in the light chain CDR3 (LCDR3) were assessed to be important. Residues in LCDR3 were mutated, and LCDR3-Tyr(92) was found to be critical for binding to Rev, as judged by surface plasmon resonance and electron microscopy. Peptides corresponding to all six CDR regions were synthesized and tested for Rev binding. None of the linear peptides had significant affinity for Rev, but four of the amide-cyclic forms did. Especially cyclic-LCDR3 (LGGYPAASYRTA) had high affinity for Rev and was able to effectively depolymerize Rev filaments, as shown by both surface plasmon resonance and electron microscopy.

  11. Screening for Antiviral Activities of Isolated Compounds from Essential Oils

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    Akram Astani

    2011-01-01

    Full Text Available Essential oil of star anise as well as phenylpropanoids and sesquiterpenes, for example, trans-anethole, eugenol, β-eudesmol, farnesol, β-caryophyllene and β-caryophyllene oxide, which are present in many essential oils, were examined for their antiviral activity against herpes simplex virus type 1 (HSV-1 in vitro. Antiviral activity was analyzed by plaque reduction assays and mode of antiviral action was determined by addition of the drugs to uninfected cells, to the virus prior to infection or to herpesvirus-infected cells. Star anise oil reduced viral infectivity by >99%, phenylpropanoids inhibited HSV infectivity by about 60–80% and sesquiterpenes suppressed herpes virus infection by 40–98%. Both, star anise essential oil and all isolated compounds exhibited anti-HSV-1 activity by direct inactivation of free virus particles in viral suspension assays. All tested drugs interacted in a dose-dependent manner with herpesvirus particles, thereby inactivating viral infectivity. Star anise oil, rich in trans-anethole, revealed a high selectivity index of 160 against HSV, whereas among the isolated compounds only β-caryophyllene displayed a high selectivity index of 140. The presence of β-caryophyllene in many essential oils might contribute strongly to their antiviral ability. These results indicate that phenylpropanoids and sesquiterpenes present in essential oils contribute to their antiviral activity against HSV.

  12. ANTI-VIRAL ACTIVITY OF GLYCIRRHETINIC AND GLYCIRRHIZIC ACIDS

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    V. V. Zarubaev

    2016-01-01

    Full Text Available Influenza is a highly contagious human disease. In the course of use of antiviral drugs drug-resistant strains of the virus are formed, resulting in reduced efficiency of the chemotherapy. The review describes the biological activity of glycirrhetinic (GLA and glycirrhizic (GA acids in terms of their use as a therapeutic agent for viral infections. So, these compounds are against a broad spectrum of viruses, including herpes, corona-, alphaand flaviviruses, human immunodeficiency virus, vaccinia virus, poliovirus type I, vesicular stomatitis virus and influenza A virus. These data indicate that anti-viral effect of these compounds is due to several types of activity — direct antiviral effects, effects on cellular proand anti-viral and immunomodulating pathways, in particular by activation of innate immunity system. GA interferes with early steps of the viral reproductive cycle such as virus binding to its receptor, the absorption of the virus by endocytosis or virus decapsidation in the cytoplasm. This is due to the effect of GA-induced reduction of membrane fluidity. Thus, one mechanism for the antiviral activity of GA is that GA molecule increases the rigidity of cellular and viral membranes after incorporation in there. This results in increasing of energy threshold required for the formation of negative curvature at the fusion zones, as well as difficult lateral migration of the virus-receptor complexes. In addition, glycyrrhizin prevents interaction of viral nucleoprotein with cellular protein HMGB1, which is necessary for the viral life cycle. Glycyrrhizin also inhibits the induction of oxidative stress during influenza infection, exhibiting antioxidant properties, which leads to a reduction of virus-induced production of cytokines/chemokines, without affecting the replication of the virus. A wide spectrum of biological activity and effect on various aspects of the viral pathogenesis substantiate the effect of GA and GLA as a component

  13. Antiviral cationic peptides as a strategy for innovation in global health therapeutics for dengue virus: high yield production of the biologically active recombinant plectasin peptide.

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    Rothan, Hussin A; Mohamed, Zulqarnain; Suhaeb, Abdulrazzaq M; Rahman, Noorsaadah Abd; Yusof, Rohana

    2013-11-01

    Dengue virus infects millions of people worldwide, and there is no vaccine or anti-dengue therapeutic available. Antimicrobial peptides have been shown to possess effective antiviral activity against various viruses. One of the main limitations of developing these peptides as potent antiviral drugs is the high cost of production. In this study, high yield production of biologically active plectasin peptide was inexpensively achieved by producing tandem plectasin peptides as inclusion bodies in E. coli. Antiviral activity of the recombinant peptide towards dengue serotype-2 NS2B-NS3 protease (DENV2 NS2B-NS3pro) was assessed as a target to inhibit dengue virus replication in Vero cells. Single units of recombinant plectasin were collected after applying consecutive steps of refolding, cleaving by Factor Xa, and nickel column purification to obtain recombinant proteins of high purity. The maximal nontoxic dose (MNTD) of the recombinant peptide against Vero cells was 20 μM (100 μg/mL). The reaction velocity of DENV2 NS2B-NS3pro decreased significantly after increasing concentrations of recombinant plectasin were applied to the reaction mixture. Plectasin peptide noncompetitively inhibited DENV2 NS2B-NS3pro at Ki value of 5.03 ± 0.98 μM. The percentage of viral inhibition was more than 80% at the MNTD value of plectasin. In this study, biologically active recombinant plectasin which was able to inhibit dengue protease and viral replication in Vero cells was successfully produced in E. coli in a time- and cost- effective method. These findings are potentially important in the development of potent therapeutics against dengue infection.

  14. Novel cycloalkylthiophene-imine derivatives bearing benzothiazole scaffold: synthesis, characterization and antiviral activity evaluation.

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    Ke, Shaoyong; Wei, Yanhong; Yang, Ziwen; Wang, Kaimei; Liang, Ying; Shi, Liqiao

    2013-09-15

    A series of novel cycloalkylthiophene-imine derivatives containing benzothiazole unit were designed, synthesized and evaluated for their anti-viral activities. The bio-evaluation results indicated that some of the target compounds (such as 5g, 5i, 5u) exhibited good to moderate antiviral effect on CVB5, ADV7 and EV71 viruses, however, these compounds did not have inhibition activity against H1N1 virus. Especially, the compounds 4c and 4d also exhibited high antiviral activities, which provide a new and efficient approach to evolve novel multi-functional antiviral agents by rational integration of active pharmacophores. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. Phosprenyl: a novel drug with antiviral and immunomodulatory activity.

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    Danilov, L L; Maltsev, S D; Deyeva, A V; Narovlyansky, A N; Sanin, A V; Ozherelkov, S V; Pronin, A V

    1996-01-01

    A novel antiviral drug with immunomodulatory activity (Phosprenyl) is presented. The main active ingredient of the preparation is polyprenyl phosphates. This medicine is highly efficient against a number of viruses, including HIV in vitro, and tick-borne encephalitis and rabies viruses in the experimental models in vivo. In veterinary practice Phosprenyl is now regarded as an effective therapeutic means for treatment of canine distemper, hepatitis, enteritis, etc.

  16. A quantitative infection assay for human type I, II, and III interferon antiviral activities

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    2013-01-01

    Background Upon virus infection, cells secrete a diverse group of antiviral molecules that signal proximal cells to enter into an antiviral state, slowing or preventing viral spread. These paracrine signaling molecules can work synergistically, so measurement of any one antiviral molecule does not reflect the total antiviral activity of the system. Results We have developed an antiviral assay based on replication inhibition of an engineered fluorescent vesicular stomatitis virus reporter strain on A549 human lung epithelial cells. Our assay provides a quantitative functional readout of human type I, II, and III interferon activities, and it provides better sensitivity, intra-, and inter-assay reproducibility than the traditional crystal violet based assay. Further, it eliminates cell fixation, rinsing, and staining steps, and is inexpensive to implement. Conclusions A dsRed2-strain of vesicular stomatitis virus that is sensitive to type I, II, and III interferons was used to develop a convenient and sensitive assay for interferon antiviral activity. We demonstrate use of the assay to quantify the kinetics of paracrine antiviral signaling from human prostate cancer (PC3) cells in response to viral infection. The assay is applicable to high-throughput screening for anti-viral compounds as well as basic studies of cellular antiviral signaling. PMID:23829314

  17. Antiviral activities of coffee extracts in vitro.

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    Utsunomiya, Hirotoshi; Ichinose, Masao; Uozaki, Misao; Tsujimoto, Kazuko; Yamasaki, Hisashi; Koyama, A Hajime

    2008-06-01

    Both hot water extracts of coffee grinds and instant coffee solutions inhibited the multiplication of herpes simplex virus type 1, a representative enveloped DNA virus, when they were added to the culture medium of the virus-infected cells at a dose of one fifth the concentration suitable for drinking. The antiherpetic activity was independent of the suppliers (companies) of the coffee grinds and of the locations where the coffee beans were produced. Further characterization revealed that there are two different mechanisms, by which the coffee extracts exert inhibitory activities on the virus infection; (1) a direct inactivation of the infectivity of virus particle (i.e., a virucidal activity) and (2) the inhibition of progeny infectious virus formation at the late stage of viral multiplication in the infected cells. Caffeine, but not quinic acid and chlorogenic acid, inhibited the virus multiplication to some extent, but none of them showed the virucidal activity, suggesting that other component(s) in the coffee extracts must play a role in the observed antiviral activity. In addition, the coffee extracts inhibited the multiplication of poliovirus, a non-enveloped RNA virus, but showed no virucidal effect on this virus.

  18. The Antiviral Activities and Mechanisms of Marine Polysaccharides: An Overview

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    Wang, Wei; Wang, Shi-Xin; Guan, Hua-Shi

    2012-01-01

    Recently, the studies on the antiviral activities of marine natural products, especially marine polysaccharides, are attracting more and more attention all over the world. Marine-derived polysaccharides and their lower molecular weight oligosaccharide derivatives have been shown to possess a variety of antiviral activities. This paper will review the recent progress in research on the antiviral activities and the mechanisms of these polysaccharides obtained from marine organisms. In particular, it will provide an update on the antiviral actions of the sulfated polysaccharides derived from marine algae including carrageenans, alginates, and fucans, relating to their structure features and the structure–activity relationships. In addition, the recent findings on the different mechanisms of antiviral actions of marine polysaccharides and their potential for therapeutic application will also be summarized in detail. PMID:23235364

  19. The Antiviral Activities and Mechanisms of Marine Polysaccharides: An Overview

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    Hua-Shi Guan

    2012-12-01

    Full Text Available Recently, the studies on the antiviral activities of marine natural products, especially marine polysaccharides, are attracting more and more attention all over the world. Marine-derived polysaccharides and their lower molecular weight oligosaccharide derivatives have been shown to possess a variety of antiviral activities. This paper will review the recent progress in research on the antiviral activities and the mechanisms of these polysaccharides obtained from marine organisms. In particular, it will provide an update on the antiviral actions of the sulfated polysaccharides derived from marine algae including carrageenans, alginates, and fucans, relating to their structure features and the structure–activity relationships. In addition, the recent findings on the different mechanisms of antiviral actions of marine polysaccharides and their potential for therapeutic application will also be summarized in detail.

  20. Structure and antiviral activity of sulfated fucans from Stoechospermum marginatum.

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    Adhikari, Utpal; Mateu, Cecilia G; Chattopadhyay, Kausik; Pujol, Carlos A; Damonte, Elsa B; Ray, Bimalendu

    2006-11-01

    A sulfated fucan containing fraction (SmWE) was isolated from water extract of the brown seaweed Stoechospermum marginatum collected from the Arabian Sea. Anion exchange chromatography of the crude fraction results in the production of a sulfated fucan (F3) having a molecular mass of 40 kDa and specific rotation [alpha]D(30) - 124 degrees (c 0.5, H2O). NMR spectroscopic studies and methylation analysis suggested that the polymer consists of a backbone of (1-->4)- and (1-->3)-linked-alpha-L-fucopyranosyl residues that are substituted at C-2 and C-3, and that fucosyl residues are sulfated mostly at C-2 and/or C-4. SmWE and F3 were selective inhibitors of herpes simplex virus type 1 (strain F, thymidine kinase-deficient strains field and B2006 and syncytial variants arising after selection with a natural carrageenan syn 13-8 and 14-1) and type 2 (strain MS) in Vero cells, with antiviral effective concentration 50% (EC50) values in the range 0.63-10.0 microg/ml. The compounds were highly selective due to the lack of cytotoxicity. The antiviral activity was dependent on the presence of the sulfated fucans during the adsorption period. No direct inactivating effect on virions was observed in a virucidal assay. The absence of anticoagulant activity at concentrations near EC50 confirmed that there was no correlation between the antiviral and anticoagulant properties.

  1. Ribonuclease, deoxyribonuclease, and antiviral activity of Escherichia coli-expressed Bougainvillea xbuttiana antiviral protein 1.

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    Choudhary, N L; Yadav, O P; Lodha, M L

    2008-03-01

    A full-length cDNA encoding ribosome-inactivating/antiviral protein from the leaves of Bougainvillea xbuttiana was recently isolated. The coding region of cDNA was cloned and expressed in Escherichia coli, and the protein product was designated as BBAP1 (Bougainvillea xbuttiana antiviral protein 1). BBAP1 showed ribonuclease activity against Torula yeast RNA. It also exhibited depurination activity against supercoiled pBlueScript SK+ plasmid DNA in a concentration dependent manner, and was found to convert nicked circular DNA into linear form only at higher concentration. On bioassay, BBAP1 exhibited antiviral activity against sunnhemp rosette virus infecting Cyamopsis tetragonoloba leaves in which 95% inhibition of local lesion formation was observed.

  2. Antiviral activity of lactoferrin towards naked viruses.

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    Seganti, Lucilla; Di Biase, Assunta Maria; Marchetti, Magda; Pietrantoni, Agostina; Tinari, Antonella; Superti, Fabiana

    2004-06-01

    It is well known that lactoferrin (Lf) is a potent inhibitor towards several enveloped and naked viruses, such as rotavirus, enterovirus and adenovirus. Lf is resistant to tryptic digestion and breast-fed infants excrete high levels of faecal Lf, so that its effect on viruses replicating in the gastrointestinal tract is of great interest. In this report, we analysed the mechanism of the antiviral action of this protein in three viral models which, despite representing different genoma and replication strategies, share the ability to infect the gut. Concerning the mechanism of action against rotavirus, Lf from bovine milk (BLf) possesses a dual role, preventing virus attachment to intestinal cells by binding to viral particles, and inhibiting a post adsorption step. The BLf effect towards poliovirus is due to the interference with an early infection step but, when the BLf molecule is saturated with Zn+2 ions, it is also capable of inhibiting viral replication after the viral adsorption phase. The anti-adenovirus action of BLf takes place on virus attachment to cell membranes through competition for common glycosaminoglycan receptors and a specific interaction with viral structural polypeptides. Taken together, these findings provide further evidence that Lf is an excellent candidate in the search of natural agents against viral enteric diseases, as it mainly acts by hindering adsorption and internalisation into cells through specific binding to cell receptors and/or viral particles.

  3. Antiviral activity of monoterpenes beta-pinene and limonene against herpes simplex virus in vitro.

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    Akram Astani

    2014-06-01

    Full Text Available Essential oils are complex mixtures containing compounds of several different functional- group classes. Depending on the structure, we can distinguish monoterpenes, phenylpropanes, and other components. Here in this study two monoterpene compounds of essential oils, i.e. β-pinene and limonene were examined for their antiviral activity against herpes simplex virus type 1 (HSV-1 in vitro.All antiviral assays were performed using RC-37 cells. Cytotoxicity was determined in a neutral red assay, antiviral assays were performed with HSV-1 strain KOS. The mode of antiviral action was evaluated at different periods during the viral replication cycle. Acyclovir was used as positive antiviral control.Beta-pinenene and limonenen reduced viral infectivity by 100 %. The mode of antiviral action has been determined, only moderate antiviral effects were revealed by monoterpenes when these drugs were added to host cells prior infection or after entry of HSV into cells. However, both monoterpenes exhibited high anti-HSV-1 activity by direct interaction with free virus particles. Both tested drugs interacted with HSV-1 in a dose-dependent manner thereby inactivating viral infection.These results suggest that monoterpenes in essential oils exhibit antiherpetic activity in the early phase of viral multiplication and might be used as potential antiviral agents.

  4. STUDY OF ANTIVIRAL ACTIVITY OF SOME HYDRAZONE PINOSTROBIN DERIVATIVES

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    G. K. Mukusheva

    2014-01-01

    Full Text Available New derivatives on the basis of hydrazone pinostrobin molecule were synthesized. Significant antiviral activity of received samples of new hydrazone pinstrobin derivatives was identified.

  5. Antiviral activity of 3(2H- and 6-chloro-3(2H-isoflavenes against highly diverged, neurovirulent vaccine-derived, type2 poliovirus sewage isolates.

    Directory of Open Access Journals (Sweden)

    Lester M Shulman

    Full Text Available BACKGROUND: Substituted flavanoids interfere with uncoating of Enteroviruses including Sabin-2 polio vaccine strains. However flavanoid resistant and dependent, type-2 polio vaccine strains (minimally-diverged, emerged during in vitro infections. Between 1998-2009, highly-diverged (8 to >15% type-2, aVDPV(2s, from two unrelated persistent infections were periodically isolated from Israeli sewage. AIM: To determine whether highly evolved aVDPV(2s derived from persistent infections retained sensitivity to isoflavenes. METHODS: Sabin-2 and ten aVDPV(2 isolates from two independent Israeli sources were titered on HEp2C cells in the presence and absence of 3(2H- Isoflavene and 6-chloro-3(2H-Isoflavene. Neurovirulence of nine aVDPV(2s was measured in PVR-Tg-21 transgenic mice. Differences were related to unique amino acid substitutions within capsid proteins. PRINCIPAL FINDINGS: The presence of either flavanoid inhibited viral titers of Sabin-2 and nine of ten aVDPV(2s by one to two log(10. The tenth aVDPV(2, which had unique amino acid substitution distant from the isoflavene-binding pocket but clustered at the three- and five-fold axies of symmetry between capsomeres, was unaffected by both flavanoids. Genotypic neurovirulence attenuation sites in the 5'UTR and VP1 reverted in all aVDPV(2s and all reacquired a full neurovirulent phenotype except one with amino acid substitutions flanking the VP1 site. CONCLUSION: Both isoflavenes worked equally well against Sabin 2 and most of the highly-diverged, Israeli, aVDPV(2s isolates. Thus, functionality of the hydrophobic pocket may be unaffected by selective pressures exerted during persistent poliovirus infections. Amino acid substitutions at sites remote from the drug-binding pocket and adjacent to a neurovirulence attenuation site may influence flavanoid antiviral activity, and neurovirulence, respectively.

  6. Antiviral and cytotoxic activities of some Indonesian plants.

    Science.gov (United States)

    Lohézic-Le Dévéhat, F; Bakhtiar, A; Bézivin, C; Amoros, M; Boustie, J

    2002-08-01

    Ten methanolic extracts from eight Indonesian medicinal plants were phytochemically screened and evaluated for antiviral (HSV-1 and Poliovirus) and cytotoxic activities on murine and human cancer lines (3LL, L1210, K562, U251, DU145, MCF-7). Besides Melastoma malabathricum (Melastomataceae), the Indonesian Loranthaceae species among which Elytranthe tubaeflora, E. maingayi, E. globosa and Scurrula ferruginea exhibited attractive antiviral and cytotoxic activities. Piper aduncum (Piperaceae) was found active on Poliovirus. S. ferruginea was selected for further studies because of its activity on the U251 glioblastoma cells.

  7. Cherry Valley ducks mitochondrial antiviral-signaling protein (MAVS mediated signaling pathway and antiviral activity research

    Directory of Open Access Journals (Sweden)

    Ning Li

    2016-09-01

    Full Text Available Mitochondrial antiviral-signaling protein (MAVS, an adaptor protein of retinoic acid-inducible gene I (RIG-I like receptors (RLRs-mediated signal pathway, is involved in innate immunity. In this study, Cherry Valley duck MAVS (duMAVS was cloned from the spleen and analyzed. duMAVS was determined to have a caspase activation and recruitment domain at N-terminal, followed by a proline rich domain and a transmembrane domain at C-terminal. Quantitative real time PCR indicated that duMAVS was expressed in all tissues tested across a broad expression spectrum. The expression of duMAVS was significantly up-regulated after infection with duck Tembusu virus. Overexpression of duMAVS could drive the activation of interferon-β, nuclear factor-κB, interferon regulatory factor 7, and many downstream factors (such as Mx, PKR, OAS, and IL-8 in duck embryo fibroblast cells. What’s more, RNA interference further confirmed that duMAVS was an important adaptor for IFN-β activation. The antiviral assay showed that duMAVS could suppress the various viral replications (duck Tembusu virus, novel reovirus, and duck plague virus at early stages of infection. Overall, these results showed that the main signal pathway mediated by duMAVS and it had a broad-spectrum antiviral ability. This research will be helpful to better understanding the innate immune system of ducks.

  8. Phytochemistry, cytotoxicity and antiviral activity of Eleusine indica (sambau)

    Science.gov (United States)

    Iberahim, Rashidah; Yaacob, Wan Ahmad; Ibrahim, Nazlina

    2015-09-01

    Goose grass also known as Eleusine indica (EI) is a local medicinal plant that displays antioxidant, antimicrobial and anticancer activities. The present study is to determine the phytochemical constituents, cytotoxicity and antiviral activities for both crude extract and fraction obtained from the plant. The crude extract contained more secondary metabolites compared to the hexane fraction as gauged using standard phytochemical tests. Cytotoxicity screening against Vero cells using MTT assay showed that the CC50 values for crude extract and hexane fraction were 2.07 and 5.62 mg/ml respectively. The antiviral activity towards Herpes Simplex Virus type 1 (HSV-1) was determined using plaque reduction assay. The selective indices (SI = CC50 / EC50) for both methanol extract and hexane fraction were 12.2 and 6.2 respectively. These results demonstrate that the extract prepared from E. indica possesses phytochemical compound that was non cytotoxic to the cell with potential antiviral activity.

  9. Mechanisms of virus resistance and antiviral activity of snake venoms

    Directory of Open Access Journals (Sweden)

    JVR Rivero

    2011-01-01

    Full Text Available Viruses depend on cell metabolism for their own propagation. The need to foster an intimate relationship with the host has resulted in the development of various strategies designed to help virus escape from the defense mechanisms present in the host. Over millions of years, the unremitting battle between pathogens and their hosts has led to changes in evolution of the immune system. Snake venoms are biological resources that have antiviral activity, hence substances of significant pharmacological value. The biodiversity in Brazil with respect to snakes is one of the richest on the planet; nevertheless, studies on the antiviral activity of venom from Brazilian snakes are scarce. The antiviral properties of snake venom appear as new promising therapeutic alternative against the defense mechanisms developed by viruses. In the current study, scientific papers published in recent years on the antiviral activity of venom from various species of snakes were reviewed. The objective of this review is to discuss the mechanisms of resistance developed by viruses and the components of snake venoms that present antiviral activity, particularly, enzymes, amino acids, peptides and proteins.

  10. Atividade antiviral de Musa acuminata Colla, Musaceae Antiviral activity of Musa acuminata Colla, Musaceae

    Directory of Open Access Journals (Sweden)

    Fernanda Otaviano Martins

    2009-09-01

    Full Text Available O presente trabalho avalia a atividade antiviral de extratos e frações de Musa acuminata Colla, Musaceae, coletada em duas regiões do Estado do Rio de Janeiro (Petrópolis e Santo Antônio de Pádua. As inflorescências de M. acuminata apresentaram excelente atividade para os dois vírus avaliados: herpesvírus simples humano tipo 1 e herpesvírus simples humano tipo 2, ambos resistentes ao Aciclovir. Os resultados indicam que os extratos de M. acuminata testados podem constituir alvo potencial para uso em terapias antivirais.This study evaluates the antiviral activity of extracts and fractions of Musa acuminata Colla collected in two regions of Rio de Janeiro State (Petrópolis and Santo Antônio de Pádua. The inflorescences of M. acuminata showed excellent activity for the two virus evaluated: simple human herpesvirus type 1 and simple human herpesvirus type 2, both resistant to Acyclovir. The results indicate that the tested extracts of M. acuminata can be potential target for use in antiviral therapy.

  11. Development of a Broad-Spectrum Antiviral Agent with Activity ...

    African Journals Online (AJOL)

    Activity Against Herpesvirus Replication and Gene. Expression ... Method: Antiviral activity against Herpes simplex virus type 1 (HSV-1) was determined using thiazolyl ..... Marker; 1 = Vero cells; 2 = HSV-1; 3 = ACV; 4 = H9);. (D) effect of H9 on ...

  12. In vitro evaluation of marine-microorganism extracts for anti-viral activity

    Directory of Open Access Journals (Sweden)

    Yasuhara-Bell Jarred

    2010-08-01

    Full Text Available Abstract Viral-induced infectious diseases represent a major health threat and their control remains an unachieved goal, due in part to the limited availability of effective anti-viral drugs and measures. The use of natural products in drug manufacturing is an ancient and well-established practice. Marine organisms are known producers of pharmacological and anti-viral agents. In this study, a total of 20 extracts from marine microorganisms were evaluated for their antiviral activity. These extracts were tested against two mammalian viruses, herpes simplex virus (HSV-1 and vesicular stomatitis virus (VSV, using Vero cells as the cell culture system, and two marine virus counterparts, channel catfish virus (CCV and snakehead rhabdovirus (SHRV, in their respective cell cultures (CCO and EPC. Evaluation of these extracts demonstrated that some possess antiviral potential. In sum, extracts 162M(4, 258M(1, 298M(4, 313(2, 331M(2, 367M(1 and 397(1 appear to be effective broad-spectrum antivirals with potential uses as prophylactic agents to prevent infection, as evident by their highly inhibitive effects against both virus types. Extract 313(2 shows the most potential in that it showed significantly high inhibition across all tested viruses. The samples tested in this study were crude extracts; therefore the development of antiviral application of the few potential extracts is dependent on future studies focused on the isolation of the active elements contained in these extracts.

  13. In vitro evaluation of marine-microorganism extracts for anti-viral activity.

    Science.gov (United States)

    Yasuhara-Bell, Jarred; Yang, Yongbo; Barlow, Russell; Trapido-Rosenthal, Hank; Lu, Yuanan

    2010-08-07

    Viral-induced infectious diseases represent a major health threat and their control remains an unachieved goal, due in part to the limited availability of effective anti-viral drugs and measures. The use of natural products in drug manufacturing is an ancient and well-established practice. Marine organisms are known producers of pharmacological and anti-viral agents. In this study, a total of 20 extracts from marine microorganisms were evaluated for their antiviral activity. These extracts were tested against two mammalian viruses, herpes simplex virus (HSV-1) and vesicular stomatitis virus (VSV), using Vero cells as the cell culture system, and two marine virus counterparts, channel catfish virus (CCV) and snakehead rhabdovirus (SHRV), in their respective cell cultures (CCO and EPC). Evaluation of these extracts demonstrated that some possess antiviral potential. In sum, extracts 162M(4), 258M(1), 298M(4), 313(2), 331M(2), 367M(1) and 397(1) appear to be effective broad-spectrum antivirals with potential uses as prophylactic agents to prevent infection, as evident by their highly inhibitive effects against both virus types. Extract 313(2) shows the most potential in that it showed significantly high inhibition across all tested viruses. The samples tested in this study were crude extracts; therefore the development of antiviral application of the few potential extracts is dependent on future studies focused on the isolation of the active elements contained in these extracts.

  14. Commensal bacteria calibrate the activation threshold of innate antiviral immunity.

    Science.gov (United States)

    Abt, Michael C; Osborne, Lisa C; Monticelli, Laurel A; Doering, Travis A; Alenghat, Theresa; Sonnenberg, Gregory F; Paley, Michael A; Antenus, Marcelo; Williams, Katie L; Erikson, Jan; Wherry, E John; Artis, David

    2012-07-27

    Signals from commensal bacteria can influence immune cell development and susceptibility to infectious or inflammatory diseases. However, the mechanisms by which commensal bacteria regulate protective immunity after exposure to systemic pathogens remain poorly understood. Here, we demonstrate that antibiotic-treated (ABX) mice exhibit impaired innate and adaptive antiviral immune responses and substantially delayed viral clearance after exposure to systemic LCMV or mucosal influenza virus. Furthermore, ABX mice exhibited severe bronchiole epithelial degeneration and increased host mortality after influenza virus infection. Genome-wide transcriptional profiling of macrophages isolated from ABX mice revealed decreased expression of genes associated with antiviral immunity. Moreover, macrophages from ABX mice exhibited defective responses to type I and type II IFNs and impaired capacity to limit viral replication. Collectively, these data indicate that commensal-derived signals provide tonic immune stimulation that establishes the activation threshold of the innate immune system required for optimal antiviral immunity. Copyright © 2012 Elsevier Inc. All rights reserved.

  15. Evaluation of antiseptic antiviral activity of chemical agents.

    Science.gov (United States)

    Geller, Chloé; Finance, Chantal; Duval, Raphaël Emmanuel

    2011-06-01

    Antiviral antisepsis and disinfection are crucial for preventing the environmental spread of viral infections. Emerging viruses and associated diseases, as well as nosocomial viral infections, have become a real issue in medical fields, and there are very few efficient and specific treatments available to fight most of these infections. Another issue is the potential environmental resistance and spread of viral particles. Therefore, it is essential to properly evaluate the efficacy of antiseptics-disinfectants (ATS-D) on viruses. ATS-D antiviral activity is evaluated by (1) combining viruses and test product for an appropriately defined and precise contact time, (2) neutralizing product activity, and (3) estimating the loss of viral infectivity. A germicide can be considered to have an efficient ATS-D antiviral activity if it induces a >3 or >4 log(10) reduction (American and European regulatory agency requirements, respectively) in viral titers in a defined contact time. This unit describes a global methodology for evaluating chemical ATS-D antiviral activity.

  16. Antiviral activity and mode of action of propolis extracts and selected compounds.

    Science.gov (United States)

    Schnitzler, Paul; Neuner, Annett; Nolkemper, Silke; Zundel, Christine; Nowack, Hans; Sensch, Karl Heinz; Reichling, Jürgen

    2010-01-01

    Aqueous and ethanol extracts of propolis were analysed phytochemically and examined for their antiviral activity in vitro. Different polyphenols, flavonoids and phenylcarboxylic acids were identified as major constituents. The antiviral effect of propolis extracts and selected constituents, e.g. caffeic acid (1), p-coumaric acid (2), benzoic acid (3), galangin (4), pinocembrin (5) and chrysin (6) against herpes simplex virus type 1 (HSV-1) was analysed in cell culture. The 50% inhibitory concentration (IC(50)) of aqueous and ethanol propolis extracts for HSV-1 plaque formation was determined at 0.0004% and 0.000035%, respectively. Both propolis extracts exhibited high levels of antiviral activity against HSV-1 in viral suspension tests, plaque formation was significantly reduced by >98%. In order to determine the mode of antiviral action of propolis, the extracts were added at different times during the viral infection cycle. Both propolis extracts exhibited high anti-HSV-1 activity when the viruses were pretreated with these drugs prior to infection. Among the analysed compounds, only galangin and chrysin displayed some antiviral activity. However, the extracts containing many different components exhibited significantly higher antiherpetic effects as well as higher selectivity indices than single isolated constituents. Propolis extracts might be suitable for topical application against herpes infection.

  17. Bilirubin: an endogenous molecule with antiviral activity in vitro.

    Directory of Open Access Journals (Sweden)

    Rosaria eSantangelo

    2012-03-01

    Full Text Available Bilirubin-IX-alpha (BR is the final product of heme metabolism through the heme oxygenase/biliverdin reductase (HO/BVR system. Previous papers reported on the microbicidal effects of the HO by-products biliverdin-IX-alpha, carbon monoxide and iron, through either direct or indirect mechanisms. In this paper the evidence of a virucidal effect of BR against human herpes simplex virus type 1 (HSV-1 and the enterovirus EV71 was provided. Bilirubin-IX-alpha, at concentrations 1-10 µM, close to those found in blood and tissues, significantly reduced HSV-1 and EV71 replication in Hep-2 and Vero cell lines, respectively. Bilirubin-IX-alpha inhibited viral infection of Hep-2 and Vero cells when given 2 hours before, concomitantly and 2 hours after viral infection. Furthermore, BR retained its antiviral activity even complexed with a saturating concentration of human serum-albumin. Moreover, 10 µM BR increased the formation of nitric oxide and the phosphorylation of JNK in Vero and Hep-2 cell lines, respectively, thus implying a role of these two pathways in the mechanism of antiviral activity of the bile pigment. In conclusion, these results support the antiviral effect of BR against HSV-1 and enterovirus in vitro, and put the basis for further basic and clinical studies to understand the real role of BR as an endogenous antiviral molecule.

  18. DMPD: What is disrupting IFN-alpha's antiviral activity? [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 15283983 What is disrupting IFN-alpha's antiviral activity? Mbow ML, Sarisky RT. Tr...ends Biotechnol. 2004 Aug;22(8):395-9. (.png) (.svg) (.html) (.csml) Show What is disrupting IFN-alpha's ant...iviral activity? PubmedID 15283983 Title What is disrupting IFN-alpha's antiviral activity? Authors Mbow ML,

  19. DMPD: Triggering the innate antiviral response through IRF-3 activation. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 17395583 Triggering the innate antiviral response through IRF-3 activation. Hiscott...g the innate antiviral response through IRF-3 activation. PubmedID 17395583 Title Triggering the innate anti...viral response through IRF-3 activation. Authors Hiscott J. Publication J Biol Ch

  20. Expression of feline interferon-alpha subtypes in Esherichia coli, and their antiviral activity and animal species specificity.

    Science.gov (United States)

    Taira, Osamu; Suzuki, Makoto; Takeuchi, Yuko; Aramaki, Yoshitaka; Sakurai, Itsuki; Watanabe, Takao; Motokawa, Kenji; Arai, Setsuo; Sato, Hisaaki; Maehara, Nobutoshi

    2005-05-01

    Two kinds of FeIFN-alpha consisting of 166 amino acids (aa) and 171 aa were expressed in Escherichia coli, and the purified proteins were tested for antiviral activity on homologous and heterologous animal cells. Crude FeIFN induced in feline cells revealed antiviral activity on both homologous and heterologous animal cells. In contrast, both types of recombinant FeIFN-alpha revealed antiviral activity only on the feline cells. All of the FeIFN-alpha subtypes showed high activity to vesicular stomatitis virus, and the three species of feline viruses belonging to different families.

  1. Synthesis and Antiviral Activities of Chiral Thiourea Derivatives

    Institute of Scientific and Technical Information of China (English)

    YAN,Zhikun; CAI,Xuejian; YANG,Xuan; SONG,Baoan; CHEN,Zhuo; BHADURY,S.Pinaki; HU,Deyu; JIN,Linhong; XUE,Wei; LU,Ping

    2009-01-01

    An environmentally benign method has been developed for the synthesis of novel chiral thiourea derivatives in high yields in ionic liquid [Bmim]PF6.The ionic solvent Call be recovered and reused without any loss of its activity.The target compounds were characterized by elemental analysis,IR,1H NMR and 13C NMR spectral data.Accord-ing to the preliminary bioassay,some of the chiral thiourea analogues exhibited moderate in vivo antiviral activities against TMV at a concentration of 500 mg/L.Title chiral compound 3i Was found to possess good in vivo protection,inactivation and curative activities of 57.O%,96.4%and 55.0%,respectively against TMV with an inhibitory concentration at 500 mg/L.The title chiral compound 3i revealed better inactivation effect on TMV(EC50=50.8pg/mL)than Ningnanmycin(EC50=60.2μg/mL).

  2. New soluble-formazan assay for HIV-1 cytopathic effects: application to high-flux screening of synthetic and natural products for AIDS-antiviral activity.

    Science.gov (United States)

    Weislow, O S; Kiser, R; Fine, D L; Bader, J; Shoemaker, R H; Boyd, M R

    1989-04-19

    We have developed an effective and optimally safe microculture method for rapid and convenient assay of the in vitro cytopathic effects of human immunodeficiency virus (HIV-1) on human lymphoblastoid or other suitable host cells. The assay procedure is applicable to the evaluation of drug effects on in vitro infections induced directly in cultured host cells by cell-free HIV-1 or by coculture with H9 cells chronically infected with HIV-1. The assay uses a newly developed tetrazolium reagent that is metabolically reduced by viable cells to yield a soluble, colored formazan product measurable by conventional colorimetric techniques. This simple microassay minimizes the number of plate manipulations typically required with other assay methods and, coupled with computerized data collection and analysis, facilitates large-scale screening of agents for potential antiviral activity. To support and enhance the discovery of new anti-HIV-1 agents, the National Cancer Institute is offering investigators worldwide the opportunity to submit new candidate agents for anti-HIV-1 screening with this method.

  3. Further evaluation of Rwandan medicinal plant extracts for their antimicrobial and antiviral activities.

    Science.gov (United States)

    Cos, P; Hermans, N; De Bruyne, T; Apers, S; Sindambiwe, J B; Vanden Berghe, D; Pieters, L; Vlietinck, A J

    2002-02-01

    A total of 45 Rwandan plant extracts, belonging to 37 different plant species out of 21 families, were investigated for their antibacterial, antifungal, and antiviral properties. The plants were selected on the base of their ethnomedicinal use against infections and autoimmune diseases. From all the plant extracts tested, only Clematis hirsuta (leaves) showed a pronounced antifungal activity against Candida albicans and the dermatophytes Trichophyton rubrum, Epidermophyton floccosum, and Microsporum canis. Seven plant extracts showed a high antiviral activity against the DNA-virus Herpes simplex type 1, while five and three plant extracts were highly active against the RNA-viruses Coxsackie and Polio, respectively. Only Macaranga kilimandscharica (leaves) showed an interesting anti-measles activity, whereas Eriosema montanum (leaves) and Entada abyssinica (leaves) were highly active against Semliki forest virus. Some plant extracts showed an antibacterial activity against Gram-positive bacteria and Mycobacterium fortuitum, but none of them were active against the Gram-negative bacteria tested.

  4. Antiviral activity of lanatoside C against dengue virus infection.

    Science.gov (United States)

    Cheung, Yan Yi; Chen, Karen Caiyun; Chen, Huixin; Seng, Eng Khuan; Chu, Justin Jang Hann

    2014-11-01

    Dengue infection poses a serious threat globally due to its recent rapid spread and rise in incidence. Currently, there is no approved vaccine or effective antiviral drug for dengue virus infection. In response to the urgent need for the development of an effective antiviral for dengue virus, the US Drug Collection library was screened in this study to identify compounds with anti-dengue activities. Lanatoside C, an FDA approved cardiac glycoside was identified as a candidate anti-dengue compound. Our data revealed that lanatoside C has an IC50 of 0.19μM for dengue virus infection in HuH-7 cells. Dose-dependent reduction in dengue viral RNA and viral proteins synthesis were also observed upon treatment with increasing concentrations of lanatoside C. Time of addition study indicated that lanatoside C inhibits the early processes of the dengue virus replication cycle. Furthermore, lanatoside C can effectively inhibit all four serotypes of dengue virus, flavivirus Kunjin, alphavirus Chikungunya and Sindbis virus as well as the human enterovirus 71. These findings suggest that lanatoside C possesses broad spectrum antiviral activity against several groups of positive-sense RNA viruses.

  5. Cytotoxicity and antiviral activities of Asplenium nidus, Phaleria macrocarpa and Eleusine indica

    Science.gov (United States)

    Tahir, Mariya Mohd; Ibrahim, Nazlina; Yaacob, Wan Ahmad

    2014-09-01

    Three local medicinal plants namely Asplenium nidus (langsuyar), Eleusine indica (sambau) and Phaleria macrocarpa (mahkota dewa) were screened for the cytotoxicity and antiviral activities. Six plant extracts were prepared including the aqueous and methanol extracts from A. nidus leaf and root, aqueous extract from dried whole plant of E. indica and methanol extract from P. macrocarpa fruits. Cytotoxicity screening in Vero cell line by MTT assay showed that the CC50 values ranged from 15 to 60 mg/mL thus indicating the safety of the extracts even at high concentrations. Antiviral properties of the plant extracts were determined by plaque reduction assay. The EC50 concentrations were between 3.2 to 47 mg/mL. The selectivity indices (SI = CC50/EC50) of each tested extracts ranged from 4.3 to 63.25 indicating the usefulness of the extracts as potential antiviral agents.

  6. In vitro characterization of the antiviral activity of fucoidan from Cladosiphon okamuranus against Newcastle Disease Virus

    Directory of Open Access Journals (Sweden)

    Elizondo-Gonzalez Regina

    2012-12-01

    Full Text Available Abstract Background Newcastle Disease Virus (NDV causes a serious infectious disease in birds that results in severe losses in the worldwide poultry industry. Despite vaccination, NDV outbreaks have increased the necessity of alternative prevention and control measures. Several recent studies focused on antiviral compounds obtained from natural resources. Many extracts from marine organisms have been isolated and tested for pharmacological purposes, and their antiviral activity has been demonstrated in vitro and in vivo. Fucoidan is a sulfated polysaccharide present in the cell wall matrix of brown algae that has been demonstrated to inhibit certain enveloped viruses with low toxicity. This study evaluated the potential antiviral activity and the mechanism of action of fucoidan from Cladosiphon okamuranus against NDV in the Vero cell line. Methods The cytotoxicity of fucoidan was determined by the MTT assay. To study its antiviral activity, fusion and plaque-forming unit (PFU inhibition assays were conducted. The mechanism of action was determined by time of addition, fusion inhibition, and penetration assays. The NDV vaccine strain (La Sota was used in the fusion inhibition assays. PFU and Western blot experiments were performed using a wild-type lentogenic NDV strain. Results Fucoidan exhibited antiviral activity against NDV La Sota, with an obtained IS50 >2000. In time of addition studies, we observed viral inhibition in the early stages of infection (0–60 min post-infection. The inhibition of viral penetration experiments with a wild-type NDV strain supported this result, as these experiments demonstrated a 48% decrease in viral infection as well as reduced HN protein expression. Ribavirin, which was used as an antiviral control, exhibited lower antiviral activity than fucoidan and high toxicity at active doses. In the fusion assays, the number of syncytia was significantly reduced (70% inhibition when fucoidan was added before cleavage of

  7. Chitosan-induced antiviral activity and innate immunity in plants.

    Science.gov (United States)

    Iriti, Marcello; Varoni, Elena Maria

    2015-02-01

    Immunity represents a trait common to all living organisms, and animals and plants share some similarities. Therefore, in susceptible host plants, complex defence machinery may be stimulated by elicitors. Among these, chitosan deserves particular attention because of its proved efficacy. This survey deals with the antiviral activity of chitosan, focusing on its perception by the plant cell and mechanism of action. Emphasis has been paid to benefits and limitations of this strategy in crop protection, as well as to the potential of chitosan as a promising agent in virus disease control.

  8. Antiviral Activity of Some Plants Used in Nepalese Traditional Medicine

    Directory of Open Access Journals (Sweden)

    M. Rajbhandari

    2009-01-01

    Full Text Available Methanolic extracts of 41 plant species belonging to 27 families used in the traditional medicine in Nepal have been investigated for in vitro antiviral activity against Herpes simplex virus type 1 (HSV-1 and influenza virus A by dye uptake assay in the systems HSV-1/Vero cells and influenza virus A/MDCK cells. The extracts of Astilbe rivularis, Bergenia ciliata, Cassiope fastigiata and Thymus linearis showed potent anti-herpes viral activity. The extracts of Allium oreoprasum, Androsace strigilosa, Asparagus filicinus, Astilbe rivularis, Bergenia ciliata and Verbascum thapsus exhibited strong anti-influenza viral activity. Only the extracts of A. rivularis and B. ciliata demonstrated remarkable activity against both viruses.

  9. Antiviral activities of medicinal plants of southern Nepal.

    Science.gov (United States)

    Taylor, R S; Hudson, J B; Manandhar, N P; Towers, G H

    1996-08-01

    In a screening of plants used traditionally in Nepal to treat diseases that could be caused by viruses, twenty-one methanol extracts from twenty species were quantitatively assayed for activity against three mammalian viruses: herpes simplex virus, Sindbis virus and poliovirus. Assays were performed in ultraviolet (UV)-A or visible light, as well as dark, and cytotoxicity was also noted. Impressive antiviral activities were exhibited by species of Bauhinia (Fabaceae), Carissa (Apocynaceae), Milletia (Fabaceae), Mallotus (Fabaceae), Rumex (Polygonaceae), Streblus (Moraceae), Terminalia (Combretaceae) and Tridax (Asteraceae). The Carissa extract was the most active, showing activity against all three viruses at a concentration of 12 micrograms/ml. Many of the other extracts showed partial inactivation of one or more test viruses.

  10. Engineering a Therapeutic Lectin by Uncoupling Mitogenicity from Antiviral Activity

    Science.gov (United States)

    Swanson, Michael D.; Boudreaux, Daniel M.; Salmon, Loïc; Chugh, Jeetender; Winter, Harry C.; Meagher, Jennifer L.; André, Sabine; Murphy, Paul V.; Oscarson, Stefan; Roy, René; King, Steven; Kaplan, Mark H.; Goldstein, Irwin J.; Tarbet, E. Bart; Hurst, Brett L.; Smee, Donald F.; de la Fuente, Cynthia; Hoffmann, Hans-Heinrich; Xue, Yi; Rice, Charles M.; Schols, Dominique; Garcia, J. Victor; Stuckey, Jeanne A.; Gabius, Hans-Joachim; Al-Hashimi, Hashim M.; Markovitz, David M.

    2015-01-01

    Summary A key effector route of the Sugar Code involves lectins that exert crucial regulatory controls by targeting distinct cellular glycans. We demonstrate that a single amino acid substitution in a banana lectin, replacing histidine 84 with a threonine, significantly reduces its mitogenicity while preserving its broad-spectrum antiviral potency. X-ray crystallography, NMR spectroscopy, and glycocluster assays reveal that loss of mitogenicity is strongly correlated with loss of pi-pi stacking between aromatic amino acids H84 and Y83, which removes a wall separating two carbohydrate binding sites, thus diminishing multivalent interactions. On the other hand, monovalent interactions and antiviral activity are preserved by retaining other wild-type conformational features and possibly through unique contacts involving the T84 side chain. Through such fine-tuning, target selection and downstream effects of a lectin can be modulated so as to knock down one activity while preserving another, thus providing tools for therapeutics and for understanding the Sugar Code. PMID:26496612

  11. A single nucleotide polymorphism of porcine MX2 gene provides antiviral activity against vesicular stomatitis virus.

    Science.gov (United States)

    Sasaki, Keisuke; Tungtrakoolsub, Pullop; Morozumi, Takeya; Uenishi, Hirohide; Kawahara, Manabu; Watanabe, Tomomasa

    2014-01-01

    The objective was to determine if single nucleotide polymorphisms (SNPs) in porcine MX2 gene affect its antiviral potential. MX proteins are known to suppress the multiplication of several viruses, including influenza virus and vesicular stomatitis virus (VSV). In domestic animals possessing highly polymorphic genome, our previous research indicated that a specific SNP in chicken Mx gene was responsible for its antiviral function. However, there still has been no information about SNPs in porcine MX2 gene. In this study, we first conducted polymorphism analysis in 17 pigs of MX2 gene derived from seven breeds. Consequently, a total of 30 SNPs, of which 11 were deduced to cause amino acid variations, were detected, suggesting that the porcine MX2 is very polymorphic. Next, we classified MX2 into eight alleles (A1-A8) and subsequently carried out infectious experiments with recombinant VSVΔG*-G to each allele. In A1-A5 and A8, position 514 amino acid (514 aa) of MX2 was glycine (Gly), which did not inhibit VSV multiplication, whereas in A6 and A7, 514 aa was arginine (Arg), which exhibited the antiviral ability against VSV. These results demonstrate that a SNP at 514 aa (Gly-Arg) of porcine MX2 plays a pivotal role in the antiviral activity as well as that at 631 aa of chicken Mx.

  12. Studies on the Antiviral Activities in vitro of Polysaccharide from Eucheuma striatum

    Institute of Scientific and Technical Information of China (English)

    CEN,Ying-Zhou; KHOO,Gaik-Ming; YE,Shao-Ming; RUI,Wen

    2004-01-01

    @@ To assay the antiviral activities on HSV-1 and CVB3 in vitro of the polysaccharide from Eucheuma striatum, its antiviral mechanism was explored. Vero cells were infected by HSV-1 and CVB3, and they were cultured with serial dilutions of polysaccharide. The cells cytotoxicity of Polysaccharide was evaluated by the MTT method. The inhibitory effects were evaluated by the cytopathic effect (CPE). Its antiviral mechanism was researched by the method of giving samples in different time. The polysaccharide could inhibit the CPE of cells infected by HSV-1 and CVB3. It showed low cytotoxicity on vero cells. Its antiviral activities were better than those of acyclovir and ribavirin which were run in parallel as the positive control samples. The polysaccharide from Eucheuma striatum has potent antiviral activities. Its antiviral mechanism is that it can prevent the virus from absorbing to the cell surface.

  13. Anti-Viral Antibody Profiling by High Density Protein Arrays

    Science.gov (United States)

    Bian, Xiaofang; Wiktor, Peter; Kahn, Peter; Brunner, Al; Khela, Amritpal; Karthikeyan, Kailash; Barker, Kristi; Yu, Xiaobo; Magee, Mitch; Wasserfall, Clive H.; Gibson, David; Rooney, Madeleine E; Qiu, Ji; LaBaer, Joshua

    2015-01-01

    Viral infections elicit anti-viral antibodies and have been associated with various chronic diseases. Detection of these antibodies can facilitate diagnosis, treatment of infection and understanding of the mechanisms of virus associated diseases. In this work, we assayed anti-viral antibodies using a novel high density-nucleic acid programmable protein array (HD-NAPPA) platform. Individual viral proteins were expressed in situ directly from plasmids encoding proteins in an array of microscopic reaction chambers. Quality of protein display and serum response was assured by comparing intra- and inter- array correlation within or between printing batches with average correlation coefficients of 0.91 and 0.96, respectively. HD-NAPPA showed higher signal to background (S/B) ratio compared with standard NAPPA on planar glass slides and ELISA. Antibody responses to 761 antigens from 25 different viruses were profiled among patients with juvenile idiopathic arthritis (JIA) and type 1 diabetes (T1D). Common as well as unique antibody reactivity patterns were detected between patients and healthy controls. We believe HD-viral-NAPPA will enable the study of host-pathogen interactions at unprecedented dimensions and elucidate the role of pathogen infections in disease development. PMID:25758251

  14. Novel Plant-Derived Recombinant Human Interferons with Broad Spectrum Antiviral Activity

    Science.gov (United States)

    2011-10-14

    compared the antiviral activities of more than 1400 plant-derived, hybrid IFNs against three RNA viruses and one DNA virus from four different families...highly pathogenic viruses with varying sensitivities to type I IFN. In particular, the DNA virus , MPXV, was not expected to be as susceptible to the...K.M., Callis, R.T., Stephen, E.L., 1980. Lassa virus infection of rhesus monkeys: pathogenesis and treatment with ribavirin. J. Infect. Dis. 141, 580

  15. Antiviral and Quantitative Structure Activity Relationship Study for Dihydropyridones Derived from Curcumin

    OpenAIRE

    Saeed, Bahjat A.; Kawkab Y. Saour; Rita S. Elias; AL-MASOUDI, NAJIM A.

    2010-01-01

    Problem statement: Pyridones are known to have variety of biological activities like antitumor, antibacterial, anti-inflammatory and antimalarial activities. This study presents antiviral evaluation of dihydropyridones derived from curcumin, as well as curcumin for comparison. Approach: The compounds evaluated for their in vitro antiviral activities against the viruses: HIV-1, Bovin viral Diarrhea, Yellow Fever, Reovirus 1, Herpesvirus 1, Vaccinia, Vescular Stomatitis, ...

  16. First discovery and stucture-activity relationship study of phenanthroquinolizidines as novel antiviral agents against tobacco mosaic virus (TMV.

    Directory of Open Access Journals (Sweden)

    Ziwen Wang

    Full Text Available A series of phenanthroquinolizidine alkaloids 1-24 were prepared and first evaluated for their antiviral activity against tobacco mosaic virus (TMV. The bioassay results showed that most of these compounds exhibited good to excellent in vivo anti-TMV activity, of which compounds 1, 2, 15 and 16 displayed significantly higher activity than (R-antofine and commercial Ningnanmycin at the same test condition. The substituents on the phenanthrene moiety play an important role for maintaining high in vivo antiviral activity. The introduction of 6-hydroxyl, which is proposed to interact with TMV RNA, did increased anti-TMV activity. The 14aR-configuration was confirmed to be the preferred antiviral configuration for phenanthroquinolizidine alkaloids. Introduction of hydroxy group at 15-position of phenanthroquinolizidine alkaloids increased activity for S-configuration but decreased activity for R-configuration. Present study provides fundamental support for development and optimization of phenanthroquinolizidine alkaloids as potential inhibitors of plant virus.

  17. First discovery and stucture-activity relationship study of phenanthroquinolizidines as novel antiviral agents against tobacco mosaic virus (TMV).

    Science.gov (United States)

    Wang, Ziwen; Feng, Anzheng; Cui, Mingbo; Liu, Yuxiu; Wang, Lizhong; Wang, Qingmin

    2012-01-01

    A series of phenanthroquinolizidine alkaloids 1-24 were prepared and first evaluated for their antiviral activity against tobacco mosaic virus (TMV). The bioassay results showed that most of these compounds exhibited good to excellent in vivo anti-TMV activity, of which compounds 1, 2, 15 and 16 displayed significantly higher activity than (R)-antofine and commercial Ningnanmycin at the same test condition. The substituents on the phenanthrene moiety play an important role for maintaining high in vivo antiviral activity. The introduction of 6-hydroxyl, which is proposed to interact with TMV RNA, did increased anti-TMV activity. The 14aR-configuration was confirmed to be the preferred antiviral configuration for phenanthroquinolizidine alkaloids. Introduction of hydroxy group at 15-position of phenanthroquinolizidine alkaloids increased activity for S-configuration but decreased activity for R-configuration. Present study provides fundamental support for development and optimization of phenanthroquinolizidine alkaloids as potential inhibitors of plant virus.

  18. Further iinvestigations on the antiviral activities of medicinal plants of togo.

    Science.gov (United States)

    Hudson, J B; Anani, K; Lee, M K; de Souza, C; Arnason, J T; Gbeassor, M

    2000-01-01

    Further studies were done on the antiviral activities of 10 species of Togolese medicinal plants, previously shown to possess activity against herpes simplex virus (HSV). The dominant activity in all cases was virucidal (direct inactivation of virus particles), although Adansonia digitata extracts also appeared to have intracellular antiviral activities as well, which could indicate the presence of multiple antiviral compounds, or a single compound with multiple actions. In the seven most active extracts, the anti-HSV activity was considerably enhanced by light, especially UVA (long wavelength UV), although they all showed "dark" antiviral activity as well. Thus, all the extracts contained antiviral photosensitizers. In all tests, the root-bark and leaf extracts of A. digitata were the most potent.

  19. Antiviral activity of squalamine: Role of electrostatic membrane binding

    Science.gov (United States)

    Beckerman, Bernard; Qu, Wei; Mishra, Abhijit; Zasloff, Michael; Wong, Gerard; Luijten, Erik

    2012-02-01

    Recent workootnotetextM. Zasloff et al., Proc. Nat. Acad. Sci. (USA) 108, 15978 (2011). has demonstrated that squalamine, a molecule found in the liver of sharks, exhibits broad-spectrum antiviral properties. It has been proposed that this activity results from the charge-density matching of squalamine and phospholipid membranes, causing squalamine to bind to membranes and displace proteins such as Rac1 that are crucial for the viral replication cycle. Here we investigate this hypothesis by numerical simulation of a coarse-grained model for the competition between Rac1 and squalamine in binding affinity to a flat lipid bilayer. We perform free-energy calculations to test the ability of squalamine to condense stacked bilayer systems and thereby displace bulkier Rac1 molecules. We directly compare our findings to small-angle x-ray scattering results for the same setup.

  20. Epimedium koreanum Nakai Displays Broad Spectrum of Antiviral Activity in Vitro and in Vivo by Inducing Cellular Antiviral State

    Directory of Open Access Journals (Sweden)

    Won-Kyung Cho

    2015-01-01

    Full Text Available Epimedium koreanum Nakai has been extensively used in traditional Korean and Chinese medicine to treat a variety of diseases. Despite the plant’s known immune modulatory potential and chemical make-up, scientific information on its antiviral properties and mode of action have not been completely investigated. In this study, the broad antiviral spectrum and mode of action of an aqueous extract from Epimedium koreanum Nakai was evaluated in vitro, and moreover, the protective effect against divergent influenza A subtypes was determined in BALB/c mice. An effective dose of Epimedium koreanum Nakai markedly reduced the replication of Influenza A Virus (PR8, Vesicular Stomatitis Virus (VSV, Herpes Simplex Virus (HSV and Newcastle Disease Virus (NDV in RAW264.7 and HEK293T cells. Mechanically, we found that an aqueous extract from Epimedium koreanum Nakai induced the secretion of type I IFN and pro-inflammatory cytokines and the subsequent stimulation of the antiviral state in cells. Among various components present in the extract, quercetin was confirmed to have striking antiviral properties. The oral administration of Epimedium koreanum Nakai exhibited preventive effects on BALB/c mice against lethal doses of highly pathogenic influenza A subtypes (H1N1, H5N2, H7N3 and H9N2. Therefore, an extract of Epimedium koreanum Nakai and its components play roles as immunomodulators in the innate immune response, and may be potential candidates for prophylactic or therapeutic treatments against diverse viruses in animal and humans.

  1. In vitro evaluation of marine-microorganism extracts for anti-viral activity

    OpenAIRE

    Yasuhara-Bell Jarred; Yang Yongbo; Barlow Russell; Trapido-Rosenthal Hank; Lu Yuanan

    2010-01-01

    Abstract Viral-induced infectious diseases represent a major health threat and their control remains an unachieved goal, due in part to the limited availability of effective anti-viral drugs and measures. The use of natural products in drug manufacturing is an ancient and well-established practice. Marine organisms are known producers of pharmacological and anti-viral agents. In this study, a total of 20 extracts from marine microorganisms were evaluated for their antiviral activity. These ex...

  2. Design, synthesis and antiviral activity of 2-(3-amino-4-piperazinylphenyl)chromone derivatives.

    Science.gov (United States)

    Kim, Mi Kyoung; Yoon, Hyunjun; Barnard, Dale Lynn; Chong, Youhoon

    2013-01-01

    Previously, we have confirmed that the antiviral activities of the chromone derivatives were controlled by the type as well as the position of the substituents attached to the chromone core structure. In the course of our ongoing efforts to optimize the antiviral activity of the chromone derivatives, we have been attempting to derivatize the chromone scaffold via introduction of various substituents. In this proof-of-concept study, we introduced a 3-amino-4-piperazinylphenyl functionality to the chromone scaffold and evaluated the antiviral activities of the resulting chromone derivatives. The synthesized 2-(3-amino-4-piperazinylphenyl)-chromones showed severe acute respiratory syndrome-corona virus (SARS-CoV)-specific antiviral activity. In particular, the 2-pyridinylpiperazinylphenyl substituents provided the resulting chromone derivatives with selective antiviral activity. Taken together, this result indicates the possible pharmacophoric role of the 2-pyridinylpiperazine functionality attached to the chromone scaffold, which warrants further in-depth structure-activity relationship study.

  3. Dufulin Activates HrBP1 to Produce Antiviral Responses in Tobacco

    Science.gov (United States)

    Chen, Zhuo; Zeng, Mengjiao; Song, Baoan; Hou, Chengrui; Hu, Deyu; Li, Xiangyang; Wang, Zhenchao; Fan, Huitao; Bi, Liang; Liu, Jiaju; Yu, Dandan; Jin, Linhong; Yang, Song

    2012-01-01

    Background Dufulin is a new antiviral agent that is highly effective against plant viruses and acts by activating systemic acquired resistance (SAR) in plants. In recent years, it has been used widely to prevent and control tobacco and rice viral diseases in China. However, its targets and mechanism of action are still poorly understood. Methodology/Principal Findings Here, differential in-gel electrophoresis (DIGE) and classical two-dimensional electrophoresis (2-DE) techniques were combined with mass spectrometry (MS) to identify the target of Dufulin. More than 40 proteins were found to be differentially expressed (≥1.5 fold or ≤1.5 fold) upon Dufulin treatment in Nicotiana tabacum K326. Based on annotations in the Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) databases, these proteins were found to be related to disease resistance. Directed acyclic graph (DAG) analysis of the various pathways demonstrated harpin binding protein-1 (HrBP1) as the target of action of Dufulin. Additionally, western blotting, semi-quantitative reverse transcription polymerase chain reaction (RT-PCR), and real time PCR analyses were also conducted to identify the specific mechanism of action of Dufulin. Our results show that activation of HrBP1 triggers the salicylic acid (SA) signaling pathway and thereby produces antiviral responses in the plant host. A protective assay based on lesion counting further confirmed the antiviral activity of Dufulin. Conclusion This study identified HrBP1 as a target protein of Dufulin and that Dufulin can activate the SA signaling pathway to induce host plants to generate antiviral responses. PMID:22662252

  4. Dufulin activates HrBP1 to produce antiviral responses in tobacco.

    Directory of Open Access Journals (Sweden)

    Zhuo Chen

    Full Text Available BACKGROUND: Dufulin is a new antiviral agent that is highly effective against plant viruses and acts by activating systemic acquired resistance (SAR in plants. In recent years, it has been used widely to prevent and control tobacco and rice viral diseases in China. However, its targets and mechanism of action are still poorly understood. METHODOLOGY/PRINCIPAL FINDINGS: Here, differential in-gel electrophoresis (DIGE and classical two-dimensional electrophoresis (2-DE techniques were combined with mass spectrometry (MS to identify the target of Dufulin. More than 40 proteins were found to be differentially expressed (≥1.5 fold or ≤1.5 fold upon Dufulin treatment in Nicotiana tabacum K(326. Based on annotations in the Gene Ontology (GO and the Kyoto Encyclopedia of Genes and Genomes (KEGG databases, these proteins were found to be related to disease resistance. Directed acyclic graph (DAG analysis of the various pathways demonstrated harpin binding protein-1 (HrBP1 as the target of action of Dufulin. Additionally, western blotting, semi-quantitative reverse transcription polymerase chain reaction (RT-PCR, and real time PCR analyses were also conducted to identify the specific mechanism of action of Dufulin. Our results show that activation of HrBP1 triggers the salicylic acid (SA signaling pathway and thereby produces antiviral responses in the plant host. A protective assay based on lesion counting further confirmed the antiviral activity of Dufulin. CONCLUSION: This study identified HrBP1 as a target protein of Dufulin and that Dufulin can activate the SA signaling pathway to induce host plants to generate antiviral responses.

  5. Targeting APOBEC3A to the viral nucleoprotein complex confers antiviral activity

    Directory of Open Access Journals (Sweden)

    Strebel Klaus

    2007-08-01

    Full Text Available Abstract Background APOBEC3 (A3 proteins constitute a family of cytidine deaminases that provide intracellular resistance to retrovirus replication and to transposition of endogenous retroelements. A3A has significant homology to the C-terminus of A3G but has only a single cytidine deaminase active site (CDA, unlike A3G, which has a second N-terminal CDA previously found to be important for Vif sensitivity and virus encapsidation. A3A is packaged into HIV-1 virions but, unlike A3G, does not have antiviral properties. Here, we investigated the reason for the lack of A3A antiviral activity. Results Sequence alignment of A3G and A3A revealed significant homology of A3A to the C-terminal region of A3G. However, while A3G co-purified with detergent-resistant viral nucleoprotein complexes (NPC, virus-associated A3A was highly detergent-sensitive leading us to speculate that the ability to assemble into NPC may be a property conveyed by the A3G N-terminus. To test this model, we constructed an A3G-3A chimeric protein, in which the N-terminal half of A3G was fused to A3A. Interestingly, the A3G-3A chimera was packaged into HIV-1 particles and, unlike A3A, associated with the viral NPC. Furthermore, the A3G-3A chimera displayed strong antiviral activity against HIV-1 and was sensitive to inhibition by HIV-1 Vif. Conclusion Our results suggest that the A3G N-terminal domain carries determinants important for targeting the protein to viral NPCs. Transfer of this domain to A3A results in A3A targeting to viral NPCs and confers antiviral activity.

  6. Antiviral activity of some Tunisian medicinal plants against Herpes simplex virus type 1.

    Science.gov (United States)

    Sassi, A Ben; Harzallah-Skhiri, F; Bourgougnon, N; Aouni, M

    2008-01-10

    Fifteen species of Tunisian traditional medicinal plants, belonging to 10 families, were selected for this study. They were Inula viscosa (L.) Ait and Reichardia tingitana (L.) Roth ssp. discolor (Pom.) Batt. (Asteraceae), Mesembryanthemum cristallinum L. and M. nodiflorum L. (Aizoaceae), Arthrocnemum indicum (Willd.) Moq., Atriplex inflata Muell., A. parvifolia Lowe var. ifiniensis (Caball) Maire, and Salicornia fruticosa L. (Chenopodiaceae), Cistus monspeliensis L. (Cistaceae), Juniperus phoenicea L. (Cupressaceae), Erica multiflora L. (Ericaceae), Frankenia pulverulenta L. (Frankeniaceae), Hypericum crispum L. (Hypericaceae), Plantago coronopus L. ssp. eu-coronopus Pilger var. vulgaris G.G. (Plantaginaceae) and Zygophyllum album L. (Zygophyllaceae). Fifty extracts prepared from those plants were screened in order to assay their antiviral activity against Herpes simplex virus type 1 (HSV-1), using neutral red incorporation. Extracts from eight plants among these 15 showed some degree of antiviral activity, while the methanolic extract of E. multiflora was highly active with EC(50) of 132.6 microg mL(-1). These results corroborate that medicinal plants from Tunisia can be a rich source of potential antiviral compounds.

  7. Synthesis and biological activity of hydroxycinnamoyl containing antiviral drugs

    Directory of Open Access Journals (Sweden)

    Chochkova Maya G.

    2014-01-01

    Full Text Available Seven N-hydroxycinnamoyl amides were synthesized by EDC/HOBt coupling of the corresponding substituted cinnamic acids (p-coumaric-, ferulic-, sinapic- and caffeic acids with influenza antivirals (amantadine, rimantadine and oseltamivir. DPPH (1,1-diphenyl-2-picrylhydrazyl scavenging abilities and the inhibitory effect on mushroom tyrosinase activity (using L-tyrosine as the substrate were investigated in vitro. Amongst the synthesized compounds, N-[(E-3-(3’,4’-dihydroxyphenyl-2-propenoyl]oseltamivir (1 and N-[(E-3-(3’,4’-dihydroxyphenyl-2-propenoyl]rimantadine (4, containing catechol moiety, exhibited the most potent DPPH radical-scavenging activity. Amide (1 displayed also tyrosinase inhibitory effect toward L-tyrosine as the substrate (~50%. Due to its biological activities revealed so far compound (1 can be considered as a promising candidate for a cosmetic ingredient. The synthesized compounds were also investigated for their in vitro inhibitory activity against the replication of influenza virus A (H3N2.

  8. Potent in vitro antiviral activity of Cistus incanus extract against HIV and Filoviruses targets viral envelope proteins.

    Science.gov (United States)

    Rebensburg, Stephanie; Helfer, Markus; Schneider, Martha; Koppensteiner, Herwig; Eberle, Josef; Schindler, Michael; Gürtler, Lutz; Brack-Werner, Ruth

    2016-02-02

    Novel therapeutic options are urgently needed to improve global treatment of virus infections. Herbal products with confirmed clinical safety features are attractive starting material for the identification of new antiviral activities. Here we demonstrate that Cistus incanus (Ci) herbal products inhibit human immunodeficiency virus (HIV) infections in vitro. Ci extract inhibited clinical HIV-1 and HIV-2 isolates, and, importantly, a virus isolate with multiple drug resistances, confirming broad anti-HIV activity. Antiviral activity was highly selective for virus particles, preventing primary attachment of the virus to the cell surface and viral envelope proteins from binding to heparin. Bioassay-guided fractionation indicated that Ci extract contains numerous antiviral compounds and therefore has favorably low propensity to induce virus resistance. Indeed, no resistant viruses emerged during 24 weeks of continuous propagation of the virus in the presence of Ci extracts. Finally, Ci extracts also inhibited infection by virus particles pseudotyped with Ebola and Marburg virus envelope proteins, indicating that antiviral activity of Ci extract extends to emerging viral pathogens. These results demonstrate that Ci extracts show potent and broad in vitro antiviral activity against viruses that cause life-threatening diseases in humans and are promising sources of agents that target virus particles.

  9. Antiviral activity of human lactoferrin : Inhibition of alphavirus interaction with heparan sulfate

    NARCIS (Netherlands)

    Waarts, Barry-Lee; Aneke, Onwuchekwa J.C.; Smit, Jolanda; Kimata, Koji; Bittman, Robert; Meijer, Dirk K.F.; Wilschut, Jan

    2005-01-01

    Human lactoferrin is a component of the non-specific immune system with distinct antiviral properties. We used alphaviruses, adapted to interaction with heparan sulfate (HS), as a tool to investigate the mechanism of lactoferrin's antiviral activity. Lactoferrin inhibited infection of BHK-21 cells b

  10. Structural, topological and vibrational properties of an isothiazole derivatives series with antiviral activities

    Science.gov (United States)

    Romani, Davide; Márquez, María J.; Márquez, María B.; Brandán, Silvia A.

    2015-11-01

    In this work, the structural, topological and vibrational properties of an isothiazole derivatives series with antiviral activities in gas and aqueous solution phases were studied by using DFT calculations. The self consistent reaction field (SCRF) method was combined with the polarized continuum (PCM) model in order to study the solvent effects and to predict their reactivities and behaviours in both media. Thus, the 3-mercapto-5-phenyl-4-isothiazolecarbonitrile (I), 3-methylthio-5-phenyl-4-isothiazolecarbonitrile (II), 3-Ethylthio-5-phenyl-4-isothiazolecarbonitrile (III), S-[3-(4-cyano-5-phenyl)isothiazolyl] ethyl thiocarbonate (IV), 5-Phenyl-3-(4-cyano-5-phenylisothiazol-3-yl) disulphanyl-4-isothiazolecarbonitrile (V) and 1,2-Bis(4-cyano-5-phenylisothiazol-3-yl) sulphanyl Ethane (VI) derivatives were studied by using the hybrid B3LYP/6-31G* method. All the properties were compared and analyzed in function of the different R groups linked to the thiazole ring. This study clearly shows that the high polarity of (I) probably explains its elevated antiviral activity due to their facility to traverse biological membranes more rapidly than the other ones while in the (IV) and (V) derivatives the previous hydrolysis of both bonds increasing their antiviral properties inside the cell probably are related to their low S-R bond order values. In addition, the complete vibrational assignments and force constants are presented.

  11. Antiviral activity and mechanism of action of arbidol against Hantaan ...

    African Journals Online (AJOL)

    Methods: HUVEC cells infected with HTNV 76-118 were treated with serially diluted arbidol solutions at. -2h (2 h before viral infection, .... murine leukemia virus (M-MLV) Reverse .... DISCUSSION. Arbidol is a small antiviral compound with a.

  12. Antiviral activity of silver nanoparticle/chitosan composites against H1N1 influenza A virus

    Science.gov (United States)

    Mori, Yasutaka; Ono, Takeshi; Miyahira, Yasushi; Nguyen, Vinh Quang; Matsui, Takemi; Ishihara, Masayuki

    2013-02-01

    Silver nanoparticle (Ag NP)/chitosan (Ch) composites with antiviral activity against H1N1 influenza A virus were prepared. The Ag NP/Ch composites were obtained as yellow or brown floc-like powders following reaction at room temperature in aqueous medium. Ag NPs (3.5, 6.5, and 12.9 nm average diameters) were embedded into the chitosan matrix without aggregation or size alternation. The antiviral activity of the Ag NP/Ch composites was evaluated by comparing the TCID50 ratio of viral suspensions treated with the composites to untreated suspensions. For all sizes of Ag NPs tested, antiviral activity against H1N1 influenza A virus increased as the concentration of Ag NPs increased; chitosan alone exhibited no antiviral activity. Size dependence of the Ag NPs on antiviral activity was also observed: antiviral activity was generally stronger with smaller Ag NPs in the composites. These results indicate that Ag NP/Ch composites interacting with viruses exhibit antiviral activity.

  13. Isolation and characterization of ZH14 with antiviral activity against Tobacco mosaic virus.

    Science.gov (United States)

    Zhou, Wen-Wen; Zhang, Li-Xiang; Zhang, Bin; Wang, Fei; Liang, Zhi-Hong; Niu, Tian-Gui

    2008-06-01

    A large number of bacteria were isolated from plant samples and screened for antiviral activity against the Tobacco mosaic virus (TMV). The bacterium ZH14, which was isolated from Chinese Anxi oolong tea, secreted the antiviral substances, having 94.2% virus inhibition when the bacterial culture filtrate and TMV extract were mixed at a ratio of 1:1. The ZH14 strain is a gram-positive, spore-forming rod and has the ability to degrade ribonucleic acid. Based on its effectiveness on virus inhibition, ZH14 was selected for characterization and was identified as a strain of the Bacillus cereus group based on phenotypic tests and comparative analysis of its 16S rDNA sequence. At the same time, we determined the antiviral product of ZH14 as an extracellular protein with high molecular mass, having an optimum temperature of 15-60 degrees C and an optimum pH of 6-10. Hence, the ZH14 strain and its culture filtrate have potential application in controlling plant diseases caused by TMV.

  14. In-vitro antiviral activity of Solanum nigrum against Hepatitis C Virus

    Directory of Open Access Journals (Sweden)

    Rehman Sidra

    2011-01-01

    Full Text Available Abstract Background Hepatitis C is a major health problem causes liver cirrhosis, hepatocellular carcinoma and death. The current treatment of standard interferon in combination with ribavirin, has limited benefits due to emergence of resistant mutations during long-term treatment, adverse side effects and high cost. Hence, there is a need for the development of more effective, less toxic antiviral agents. Results The present study was designed to search anti-HCV plants from different areas of Pakistan. Ten medicinal plants were collected and tested for anti-HCV activity by infecting the liver cells with HCV 3a innoculum. Methanol and chloroform extracts of Solanum nigrum (SN seeds exhibited 37% and more than 50% inhibition of HCV respectively at non toxic concentration. Moreover, antiviral effect of SN seeds extract was also analyzed against HCV NS3 protease by transfecting HCV NS3 protease plasmid into liver cells. The results demonstrated that chloroform extract of SN decreased the expression or function of HCV NS3 protease in a dose- dependent manner and GAPDH remained constant. Conclusion These results suggest that SN extract contains potential antiviral agents against HCV and combination of SN extract with interferon will be better option to treat chronic HCV.

  15. Antiviral activity of Thiosemicarbazones derived from α-amino acids against Dengue virus.

    Science.gov (United States)

    Padmanabhan, Padmapriya; Khaleefathullah, Sheriff; Kaveri, Krishansamy; Palani, Gunasekaran; Ramanathan, Giriprasath; Thennarasu, Sathiah; Tirichurapalli Sivagnanam, Uma

    2017-03-01

    The endemicity and seasonal outbreaks of Dengue disease in most tropical and subtropical countries underscores an urgent need to develop effective prevention and control measures. Development of a Dengue vaccine, which is complicated by the Antibody Dependent Enhancement effect (ADE), a viral inhibitor, seems prudent as it would inhibit the spread of the virus. In vitro methods such as MTT assay and plaque formation unit reduction assays were employed for screening the viral inhibitory property of α-amino acid based Thiosemicarbazides. The results elicits that at concentrations not exceeding the maximum non cytotoxic concentration (MNCC), these compounds completely prevented Dengue virus infection in vero cells as indicated by the absence of cytopathic effects in a dose-dependent manner. The high potency of Bz-Trp-TSC against all four types of Dengue virus infection elevates Thiosemicarbazide as a lead antiviral agent for Dengue disease. Screening small molecules for antiviral activity against the most rapidly spreading mosquito-borne viral disease is being explored by several research groups. Our findings would help to augment the efforts to identify the lead compounds for antiviral therapy to combat the Dengue disease. J. Med. Virol. 89:546-552, 2017. © 2016 Wiley Periodicals, Inc.

  16. Structural basis for the antiviral activity of BST-2/tetherin and its viral antagonism

    Directory of Open Access Journals (Sweden)

    Juan F. eArias

    2011-12-01

    Full Text Available The interferon-inducible host restriction factor bone marrow stromal antigen 2 (BST-2/tetherin blocks the release of HIV-1 and other enveloped viruses. In turn, these viruses have evolved specific antagonists to counteract this host antiviral molecule, such as the HIV-1 protein Vpu. BST-2 is a type II transmembrane protein with an unusual topology consisting of an N-terminal cytoplasmic tail (CT followed by a single transmembrane (TM domain, a coiled-coil extracellular (EC domain, and a glycosylphosphatidylinositol (GPI anchor at the C terminus. We and others showed that BST-2 restricts enveloped virus release by bridging the host and virion membranes with its two opposing membrane anchors and that deletion of either one completely abrogates antiviral activity. The EC domain also shows conserved structural properties that are required for antiviral function. It contains several destabilizing amino acids that confer the molecule with conformational flexibility to sustain the protein's function as a virion tether, and three conserved cysteine residues that mediate homodimerization of BST-2, as well as acting as a molecular ruler that separates the membrane anchors. Conversely, the efficient release of virions is promoted by the HIV-1 Vpu protein and other viral antagonists. Our group and others provided evidence from mutational analyses indicating that Vpu antagonism of BST-2-mediated viral restriction requires a highly specific interaction of their mutual TM domains. This interpretation is further supported and expanded by the findings of the latest structural modeling studies showing that critical amino acids in a conserved helical face of these TM domains are required for Vpu-BST-2 interaction and antagonism. In this review, we summarize the current advances in our understanding of the structural basis for BST-2 antiviral function as well as BST-2-specific viral antagonism.

  17. Characterization of a Novel Human-Specific STING Agonist that Elicits Antiviral Activity Against Emerging Alphaviruses.

    Directory of Open Access Journals (Sweden)

    Tina M Sali

    2015-12-01

    Full Text Available Pharmacologic stimulation of innate immune processes represents an attractive strategy to achieve multiple therapeutic outcomes including inhibition of virus replication, boosting antitumor immunity, and enhancing vaccine immunogenicity. In light of this we sought to identify small molecules capable of activating the type I interferon (IFN response by way of the transcription factor IFN regulatory factor 3 (IRF3. A high throughput in vitro screen yielded 4-(2-chloro-6-fluorobenzyl-N-(furan-2-ylmethyl-3-oxo-3,4-dihydro-2H-benzo[b][1,4]thiazine-6-carboxamide (referred to herein as G10, which was found to trigger IRF3/IFN-associated transcription in human fibroblasts. Further examination of the cellular response to this molecule revealed expression of multiple IRF3-dependent antiviral effector genes as well as type I and III IFN subtypes. This led to the establishment of a cellular state that prevented replication of emerging Alphavirus species including Chikungunya virus, Venezuelan Equine Encephalitis virus, and Sindbis virus. To define cellular proteins essential to elicitation of the antiviral activity by the compound we employed a reverse genetics approach that utilized genome editing via CRISPR/Cas9 technology. This allowed the identification of IRF3, the IRF3-activating adaptor molecule STING, and the IFN-associated transcription factor STAT1 as required for observed gene induction and antiviral effects. Biochemical analysis indicates that G10 does not bind to STING directly, however. Thus the compound may represent the first synthetic small molecule characterized as an indirect activator of human STING-dependent phenotypes. In vivo stimulation of STING-dependent activity by an unrelated small molecule in a mouse model of Chikungunya virus infection blocked viremia demonstrating that pharmacologic activation of this signaling pathway may represent a feasible strategy for combating emerging Alphaviruses.

  18. Design, Synthesis and Antiviral Activity of 2-(3-Amino-4-piperazinylphenyl)chromone Derivatives

    National Research Council Canada - National Science Library

    Kim, Mi Kyoung; Yoon, Hyunjun; Barnard, Dale Lynn; Chong, Youhoon

    2013-01-01

    Previously, we have confirmed that the antiviral activities of the chromone derivatives were controlled by the type as well as the position of the substituents attached to the chromone core structure...

  19. Antiviral activity of glycyrrhizin against hepatitis C virus in vitro.

    Directory of Open Access Journals (Sweden)

    Yoshihiro Matsumoto

    Full Text Available Glycyrrhizin (GL has been used in Japan to treat patients with chronic viral hepatitis, as an anti-inflammatory drug to reduce serum alanine aminotransferase levels. GL is also known to exhibit various biological activities, including anti-viral effects, but the anti-hepatitis C virus (HCV effect of GL remains to be clarified. In this study, we demonstrated that GL treatment of HCV-infected Huh7 cells caused a reduction of infectious HCV production using cell culture-produced HCV (HCVcc. To determine the target step in the HCV lifecycle of GL, we used HCV pseudoparticles (HCVpp, replicon, and HCVcc systems. Significant suppressions of viral entry and replication steps were not observed. Interestingly, extracellular infectivity was decreased, and intracellular infectivity was increased. By immunofluorescence and electron microscopic analysis of GL treated cells, HCV core antigens and electron-dense particles had accumulated on endoplasmic reticulum attached to lipid droplet (LD, respectively, which is thought to act as platforms for HCV assembly. Furthermore, the amount of HCV core antigen in LD fraction increased. Taken together, these results suggest that GL inhibits release of infectious HCV particles. GL is known to have an inhibitory effect on phospholipase A2 (PLA2. We found that group 1B PLA2 (PLA2G1B inhibitor also decreased HCV release, suggesting that suppression of virus release by GL treatment may be due to its inhibitory effect on PLA2G1B. Finally, we demonstrated that combination treatment with GL augmented IFN-induced reduction of virus in the HCVcc system. GL is identified as a novel anti-HCV agent that targets infectious virus particle release.

  20. Synthesis and Antiviral Activity of 3-Aminoindole Nucleosides of 2-Acetamido-2-deoxy-D-glucose

    Energy Technology Data Exchange (ETDEWEB)

    Abdelrahman, Adel A. H.; Elessawy, Farag A.; Barakat, Yousif A. [Menoufia Univ., Shebin El-Koam (Egypt); Ellatif, Mona M. Abd [The British Univ. in Egypt, Cairo (Egypt)

    2012-10-15

    A new method for the construction of 3-aminoindole nucleosides of 2-acetamido-2-deoxy-D-glucose based is presented. Nitration and acetylation of the indole nucleosides by acetic anhydride-nitric acid mixture followed by reduction using silver catalyst (SNSM) impregnated on silica gel, afforded the corresponding amino indole nucleosides. The nucleosides were tested for antiviral activity against hepatitis B virus (HBV) to show different degrees of antiviral activities or inhibitory actions.

  1. Small molecules with antiviral activity against the Ebola virus.

    Science.gov (United States)

    Litterman, Nadia; Lipinski, Christopher; Ekins, Sean

    2015-01-01

    The recent outbreak of the Ebola virus in West Africa has highlighted the clear shortage of broad-spectrum antiviral drugs for emerging viruses. There are numerous FDA approved drugs and other small molecules described in the literature that could be further evaluated for their potential as antiviral compounds. These molecules are in addition to the few new antivirals that have been tested in Ebola patients but were not originally developed against the Ebola virus, and may play an important role as we await an effective vaccine. The balance between using FDA approved drugs versus novel antivirals with minimal safety and no efficacy data in humans should be considered. We have evaluated 55 molecules from the perspective of an experienced medicinal chemist as well as using simple molecular properties and have highlighted 16 compounds that have desirable qualities as well as those that may be less desirable. In addition we propose that a collaborative database for sharing such published and novel information on small molecules is needed for the research community studying the Ebola virus.

  2. Antiviral Activity of Isatis indigotica Extract and Its Derived Indirubin against Japanese Encephalitis Virus

    Directory of Open Access Journals (Sweden)

    Shu-Jen Chang

    2012-01-01

    Full Text Available Isatis indigotica is widely used in Chinese Traditional Medicine for clinical treatment of virus infection, tumor, and inflammation, yet its antiviral activities remain unclear. This study probed antiviral activity of I. indigotica extract and its marker compounds against Japanese encephalitis virus (JEV. I. indigotica methanol extract, indigo, and indirubin proved less cytotoxic than other components, showing inhibitory effect (concentration-dependent on JEV replication in vitro. Time-of-addition experiments proved the extract, indigo, and indirubin with potent antiviral effect by pretreatment (before infection or simultaneous treatment (during infection, but not posttreatment (after entry. Antiviral action of these agents showed correlation with blocking virus attachment and exhibited potent virucidal activity. In particular, indirubin had strong protective ability in a mouse model with lethal JEV challenge. The study could yield anti-JEV agents.

  3. Streptovirudins -- new antibiotics with antiviral activity. The antiviral spectrum and inhibition of Newcastle disease virus in cell cultures.

    Science.gov (United States)

    Tonew, E; Tonew, M; Eckardt, K; Thrum, H; Gumpert, B

    1975-07-01

    Streptovirudins are new antibiotics isolated as a mixture of several structurally related compounds from fermentations of Streptomyces griseoflavus (Krainsky) Waksman et Henrici var. thuringensis JA 10124. They possess antiviral activity against RNA and DNA viruses cultivated in chick embryo cells, namely Sindbis, fowl plague, Newcastle disease (NDV), pseudorabies, vaccinia and sheep abortion viruses. The naturally formed streptovirudin complex, in concentrations of 20-2.5 mug/ml inhibited the viral cytopathic effect and caused 100 percent plaque reduction. Mengo, Coxsackie B1-B5, ECHO 30 and 33, and polio (wild and attenuated types 1, 2, and 3) viruses grown in FL cells were not sensitive in the agar-diffusion plaque-inhibition test. The antibiotics failed to show a direct virucidal effect on the NDV virion itself or to influence virus adsorption and penetration processes. Addition of streptovirudin complex during a one-step growth cycle of NDV from 0-4 hours after virus adsorption resulted in complete suppression of virus yield. The antibiotic complex consists of two main groups: I - A1, B1, C1, D1, E1 and II - A2, B2, C2, D2, E2, each of which possess antiviral activity.

  4. [Antiviral activity of polyprenylphosphates in experimental infection caused by hepatitis C virus in vitro].

    Science.gov (United States)

    Narovlianskiĭ, A N; Deriabin, P G; Sedov, A M; Sanin, A V; Pronin, A V

    2012-01-01

    Study antiviral effect of sodium polyprenylphosphate (PPP) in experimental infection model caused by hepatitis C virus (HCV) in cell culture. Cytopathogenic variant of HCV isolated from blood serum of a chronically infected patient was used. HCV infectious dose was 10.0 TCD50. Highly sensitive to cytopathogenic effect of HCV continuous swine embryo kidney cells (SPEV) as 1 day monolayer grown in 24 well plastic plates on 199 medium with 10% calf serum with addition of L-glutamine and antibiotics (100 U/ml) were used. PPP was used in concentrations that do not have cytotoxic effect (from 60 to 7.5 microg in 50 microl); introduced into SPEV cell cultures immediately after infection, 24 hours before or 24 hours after the infection of cells with HCV. Infectious activity of HCV was evaluated by using Reed-Muench formula based on results of medium samples titration obtained 3 days after the infection of cells. PPP was shown to have antiviral properties when added into the cell cultures immediately after the infection with HCV. Under the effect of PPP HCV titers were established to decrease by 3.0 lg (PPV dose of 60 microg) and by 1.9 lg (PPV dose of 30 microg). Positive effect was also obtained for prophylactic use of PPP. When PPP at a dose of 60 microg was introduced 24 hours before the infection of SPEV with HCV, the titer of the virus decreased by 3.5 lg. Prophylactic administration of low doses of the preparation (7.5 and 15.0 microg) also showed evident antiviral effect (decrease of infectious activity of HCV by 3.2 - 2.3 lg, respectively). PPP at the doses tested has an ability to reduce concentration of HCV in SPEV cell cultures when added immediately after infection or 24 hours before.

  5. Antiviral Activity of Resveratrol against Human and Animal Viruses

    Directory of Open Access Journals (Sweden)

    Yusuf Abba

    2015-01-01

    Full Text Available Resveratrol is a potent polyphenolic compound that is being extensively studied in the amelioration of viral infections both in vitro and in vivo. Its antioxidant effect is mainly elicited through inhibition of important gene pathways like the NF-κβ pathway, while its antiviral effects are associated with inhibitions of viral replication, protein synthesis, gene expression, and nucleic acid synthesis. Although the beneficial roles of resveratrol in several viral diseases have been well documented, a few adverse effects have been reported as well. This review highlights the antiviral mechanisms of resveratrol in human and animal viral infections and how some of these effects are associated with the antioxidant properties of the compound.

  6. Identification of a novel multiple kinase inhibitor with potent antiviral activity against influenza virus by reducing viral polymerase activity

    Energy Technology Data Exchange (ETDEWEB)

    Sasaki, Yutaka; Kakisaka, Michinori; Chutiwitoonchai, Nopporn [Viral Infectious Diseases Unit, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Tajima, Shigeru [Department of Virology I, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku, Tokyo 162-8640 (Japan); Hikono, Hirokazu; Saito, Takehiko [Influenza and Prion Disease Research Center, National Institute of Animal Health, National Agriculture and Food Research Organization (NARO), 3-1-5 Kannondai, Tsukuba, Ibaraki 305-0856 (Japan); Aida, Yoko, E-mail: aida@riken.jp [Viral Infectious Diseases Unit, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan)

    2014-07-18

    Highlights: • Screening of 50,000 compounds and subsequent lead optimization identified WV970. • WV970 has antiviral effects against influenza A, B and highly pathogenic viral strains. • WV970 inhibits viral genome replication and transcription. • A target database search suggests that WV970 may bind to a number of kinases. • KINOMEscan screening revealed that WV970 has inhibitory effects on 15 kinases. - Abstract: Neuraminidase inhibitors are the only currently available influenza treatment, although resistant viruses to these drugs have already been reported. Thus, new antiviral drugs with novel mechanisms of action are urgently required. In this study, we identified a novel antiviral compound, WV970, through cell-based screening of a 50,000 compound library and subsequent lead optimization. This compound exhibited potent antiviral activity with nanomolar IC{sub 50} values against both influenza A and B viruses but not non-influenza RNA viruses. Time-of-addition and indirect immunofluorescence assays indicated that WV970 acted at an early stage of the influenza life cycle, but likely after nuclear entry of viral ribonucleoprotein (vRNP). Further analyses of viral RNA expression and viral polymerase activity indicated that WV970 inhibited vRNP-mediated viral genome replication and transcription. Finally, structure-based virtual screening and comprehensive human kinome screening were used to demonstrate that WV970 acts as a multiple kinase inhibitor, many of which are associated with influenza virus replication. Collectively, these results strongly suggest that WV970 is a promising anti-influenza drug candidate and that several kinases associated with viral replication are promising drug targets.

  7. New imidazolidineiminothione derivatives: Synthesis, spectral characterization and evaluation of antitumor, antiviral, antibacterial and antifungal activities.

    Science.gov (United States)

    Moussa, Ziad; El-Sharief, Marwa A M Sh; Abbas, Samir Y

    2016-10-21

    A series of new imidazolidineiminothione derivatives with various halogenated and alkylated aromatic substituents at N-(1) and at N-(3) was synthesized through the reaction of N-arylcyanothioformamides with arylisocyanate derivatives. Structure of imidazolidineiminothione derivatives were established based on spectroscopic IR, (1)H NMR, (13)C NMR, (1)H,(1)H-COSY, HSQC, (19)F NMR, MS and elemental analyses data. Evaluation of antitumor, antiviral, antibacterial and antifungal activities for the synthesized compounds were carried out to probe their activities. Most of the synthesized compounds displayed antitumor activity. The presence of 3,5-dichlorophenyl moiety at N-(1) and trichlorophenyl moiety on N-(3) (2f) resulted the highest cytotoxic activity. The presence of 9H-fluorenyl moiety on N-(3) resulted in the lowest cytotoxic activity. The antiviral screening displayed that 2d and 2f were markedly active against one or two viral strains. Compound 2d (3,5-dichlorophenyl moiety at N-(1) and 4-chlorophenyl moiety on N-(3)) showed 100% antiviral effect toward HAV. Compound 2f showed 96.7% antiviral effect toward HSV1 and 80.3% antiviral effect toward HAV. The antimicrobial activity suggested that all of the imidazolidineiminothione derivatives possess significant antimicrobial activity against most of the test organisms. Some imidazolidineiminothione derivatives showed MIC values of antibacterial and antifungal activities ranged from 0.78 to 6.25 μg/ml.

  8. Antibacterial, antifungal and antiviral activity of propolis of different geographic origin.

    Science.gov (United States)

    Kujumgiev, A; Tsvetkova, I; Serkedjieva, Y; Bankova, V; Christov, R; Popov, S

    1999-03-01

    Propolis samples from different geographic origins were investigated for their antibacterial (against Staphylococcus aureus and Escherichia coli), antifungal (against Candida albicans) and antiviral (against Avian influenza virus) activities. All samples were active against the fungal and Gram-positive bacterial test strains, and most showed antiviral activity. The activities of all samples were similar in spite of the differences in their chemical composition. In samples from the temperate zone, flavonoids and esters of phenolic acids are known to be responsible for the above mentioned activities of bee glue; tropical samples did not contain such substances but showed similar activities. Obviously, in different samples, different substance combinations are essential for the biological activity of the bee glue. It seems that propolis has general pharmacological value as a natural mixture and not as a source of new powerful antimicrobial, antifungal and antiviral compounds.

  9. Antiviral activity of Ageratina havanensis and major chemical compounds from the most active fraction

    Directory of Open Access Journals (Sweden)

    Gloria del Barrio

    2011-10-01

    Full Text Available The antiviral activity of extracts obtained from Ageratina havanensis (Kunth R.M.King & H.Rob., Asteraceae, against rabbit vesivirus (RaV (Caliciviridae and human herpes simplex viruses type 1 and 2 (HSV-1, HSV-2 (Herpesviridae were analyzed, and the main metabolites from the most active extract were isolated and characterized. The antiviral properties were investigated by measuring the inhibition of viral-induced cytopathic effect in Vero cells. The strongest inhibitory effects were found for ethyl acetate extract from leaves (SI=5 for RaV and SI=5.4 for HSV-1. The crude ethyl acetate extract was further fractionated by chromatographic methods and the structures of isolated compounds were established through comprehensive spectroscopic analyses, including IR, 2D NMR and MS. Four flavonoids were identified: 5,4'-dihydroxy-7-methoxyflavanone (sakuranetin, 3,5,4'-trihydroxy-7-methoxyflavanone (7-methoxyaromadendrin, 4'-O-β-D-glucosyl-5,3'-dihydroxy-7-methoxyflavanone (4'-O-β-D-glucosyl-7-methoxy-eriodictyol and 4'-O-β-D-glucosyl-5-hydroxy-7-methoxyflavanone (4'-O-β-D-glucosylsakuranetin. This is the first report on antiviral activity for Ageratina havanensis.

  10. Antiviral Activity of Sulfated Polysaccharide of Adenanthera pavonina against Poliovirus in HEp-2 Cells.

    Science.gov (United States)

    de Godoi, Ananda Marques; Faccin-Galhardi, Lígia Carla; Lopes, Nayara; Rechenchoski, Daniele Zendrini; de Almeida, Raimundo Rafael; Ricardo, Nágila Maria Pontes Silva; Nozawa, Carlos; Linhares, Rosa Elisa Carvalho

    2014-01-01

    Adenanthera pavonina, popularly known as red-bead tree, carolina, pigeon's eye, and dragon's eye, is a plant traditionally used in Brazil for the treatment of several diseases. The present study aimed at evaluating the activity of sulfated polysaccharide from the Adenanthera pavonina (SPLSAp) seeds against poliovirus type 1 (PV-1) in HEp-2 cell cultures. The SPLSAp presented a cytotoxic concentration (CC50) of 500 μg/mL in HEp-2 cell cultures, evaluated by the dimethylthiazolyl-diphenyltetrazolium bromide method (MTT). The SPLSAp exhibited a significant antiviral activity, with a 50% inhibitory concentration (IC50) of 1.18 µg/mL, determined by plaque reduction assay and a high selectivity index (SI) of 423. The maximum inhibition (100%) of PV replication was found when the SPLSAp treatment was concomitant with viral infection (time 0 h), at all tested concentrations. The maximal inhibition was also found when the SPLSAp was used 1 h and 2 h postinfection, albeit at 50 μg/mL and 100 μg/mL. Therefore, we demonstrated that the SPLSAp inhibited PV growth. We also suggested that SPLSAp inhibited PV in more than one step of the replication, as the mechanism of antiviral action. We, therefore, selected the compound as a potential candidate for further development towards the control of the infection.

  11. High throughput screening for small molecule enhancers of the interferon signaling pathway to drive next-generation antiviral drug discovery.

    Directory of Open Access Journals (Sweden)

    Dhara A Patel

    Full Text Available Most of current strategies for antiviral therapeutics target the virus specifically and directly, but an alternative approach to drug discovery might be to enhance the immune response to a broad range of viruses. Based on clinical observation in humans and successful genetic strategies in experimental models, we reasoned that an improved interferon (IFN signaling system might better protect against viral infection. Here we aimed to identify small molecular weight compounds that might mimic this beneficial effect and improve antiviral defense. Accordingly, we developed a cell-based high-throughput screening (HTS assay to identify small molecules that enhance the IFN signaling pathway components. The assay is based on a phenotypic screen for increased IFN-stimulated response element (ISRE activity in a fully automated and robust format (Z'>0.7. Application of this assay system to a library of 2240 compounds (including 2160 already approved or approvable drugs led to the identification of 64 compounds with significant ISRE activity. From these, we chose the anthracycline antibiotic, idarubicin, for further validation and mechanism based on activity in the sub-µM range. We found that idarubicin action to increase ISRE activity was manifest by other members of this drug class and was independent of cytotoxic or topoisomerase inhibitory effects as well as endogenous IFN signaling or production. We also observed that this compound conferred a consequent increase in IFN-stimulated gene (ISG expression and a significant antiviral effect using a similar dose-range in a cell-culture system inoculated with encephalomyocarditis virus (EMCV. The antiviral effect was also found at compound concentrations below the ones observed for cytotoxicity. Taken together, our results provide proof of concept for using activators of components of the IFN signaling pathway to improve IFN efficacy and antiviral immune defense as well as a validated HTS approach to identify

  12. Evaluation of antiviral activity of essential oil of Trachyspermum Ammi against Japanese encephalitis virus

    Directory of Open Access Journals (Sweden)

    Soumen Roy

    2015-01-01

    Full Text Available Background: Japanese encephalitis is a leading form of viral encephalitis, prevalent mostly in South Eastern Asia caused by Japanese encephalitis virus (JEV. It is transmitted by the mosquitoes of the Culex sp. The disease affects children and results in 50% result in permanent neuropsychiatric disorder. There arises a need to develop a safe, affordable, and potent anti-viral agent against JEV. This study aimed to assess the antiviral activity of ajwain (Trachyspermum ammi: Umbellifereae essential oil against JEV. Materials and Methods: Ajwain oil was extracted by distillation method and in vitro cytotoxicity assay was performed in vero cell line by 3-(4, 5-dimethylthiazol-2-yl-2, 5-diphenyltetrazolium bromide (MTT assay method. JEV titer was determined by plaque assay and in vitro antiviral activity of ajwain oil was quantified by the plaque reduction neutralization test (PRNT. Results: Cytotoxic concentration of the oil was found to be 1 mg/ml by MTT assay. The titer of the virus pool was found to be 50× 10 7 PFU/ml. we observed 80% and 40% virus inhibition in 0.5mg/ml of ajwain oil by PRNT method in preexposure treatment and postexposure treatment (antiviral activity, respectively. Conclusion: Our data indicate ajwain oil has potential in vitro antiviral activity against JEV. Further, the active biomolecule will be purified and evaluated for anti-JEV activity and also to scale up for in vivo trial to evaluate the efficacy of ajwain oil in future.

  13. Synthesis, antiviral and antitumor activity of 2-substituted-5-amidino-benzimidazoles.

    Science.gov (United States)

    Starcević, Kristina; Kralj, Marijeta; Ester, Katja; Sabol, Ivan; Grce, Magdalena; Pavelić, Kresimir; Karminski-Zamola, Grace

    2007-07-01

    We have prepared a set of heterocyclic benzimidazole derivatives bearing amidino substituents at C-5 of benzimidazole ring, by introducing various heterocyclic nuclei (pyridine, N-methyl-pyrrole or imidazole) at C-2, and evaluated their antitumor and antiviral activities. The most pronounced antiproliferative activity was shown with compounds 6 and 9, having imidazolinylamidino-substituent. Interestingly, all compounds show noticeable selectivity toward breast cancer cell line MCF-7. The most distinct and selective antiviral activity toward coxsackieviruses and echoviruses was observed with compounds having pyridine ring at C-2. Especially interesting was fairly strong activity of 4 and 8 toward adenoviruses, which could be considered as leads against adenoviral replication.

  14. Antiviral Activities and Putative Identification of Compounds in Microbial Extracts from the Hawaiian Coastal Waters

    Directory of Open Access Journals (Sweden)

    Yuanan Lu

    2012-02-01

    Full Text Available Marine environments are a rich source of significant bioactive compounds. The Hawaiian archipelago, located in the middle of the Pacific Ocean, hosts diverse microorganisms, including many endemic species. Thirty-eight microbial extracts from Hawaiian coastal waters were evaluated for their antiviral activity against four mammalian viruses including herpes simplex virus type one (HSV-1, vesicular stomatitis virus (VSV, vaccinia virus and poliovirus type one (poliovirus-1 using in vitro cell culture assay. Nine of the 38 microbial crude extracts showed antiviral potencies and three of these nine microbial extracts exhibited significant activity against the enveloped viruses. A secosteroid, 5α(H,17α(H,(20R-beta-acetoxyergost-8(14-ene was putatively identified and confirmed to be the active compound in these marine microbial extracts. These results warrant future in-depth tests on the isolation of these active elements in order to explore and validate their antiviral potential as important therapeutic remedies.

  15. Antioxidant, antifungal and antiviral activities of chitosan from the larvae of housefly, Musca domestica L.

    Science.gov (United States)

    Ai, Hui; Wang, Furong; Xia, Yuqian; Chen, Xiaomin; Lei, Chaoliang

    2012-05-01

    Antioxidant activity of the chitosan from the larvae of Musca domestica L. was evaluated in two different reactive oxygen species assays, and inhibitory effects against seven fungi were also tested. The results showed that the chitosan had scavenging activity for hydroxyl and superoxide radicals which were similar to that of ascorbic acid. Also the chitosan exhibited excellent antifungal activity, especially in the low concentration, it could significantly inhibit the growth of Rhizopus stolonifer. Besides, antiviral results demonstrated that the chitosan could effectively inhibit the infection of AcMNPV and BmNPV. These results suggested that the chitosan from the larvae of housefly could be effectively used as a natural antioxidant to protect the human body from free radicals and retard the progress of many chronic diseases. Furthermore, the chitosan with antiviral and antifungal activity might provide useful information for antiviral breeding technology of economic insect and development of plant pathological control.

  16. Synthesis and Broad-Spectrum Antiviral Activity of Some Novel Benzo-Heterocyclic Amine Compounds

    Directory of Open Access Journals (Sweden)

    Da-Jun Zhang

    2014-01-01

    Full Text Available A series of novel unsaturated five-membered benzo-heterocyclic amine derivatives were synthesized and assayed to determine their in vitro broad-spectrum antiviral activities. The biological results showed that most of our synthesized compounds exhibited potent broad-spectrum antiviral activity. Notably, compounds 3f (IC50 = 3.21–5.06 μM and 3g (IC50 = 0.71–34.87 μM showed potent activity towards both RNA viruses (influenza A, HCV and Cox B3 virus and a DNA virus (HBV at low micromolar concentrations. An SAR study showed that electron-withdrawing substituents located on the aromatic or heteroaromatic ring favored antiviral activity towards RNA viruses.

  17. Antiviral Activity of Natural Products Extracted from Marine Organisms

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    Sobia Tabassum

    2011-11-01

    Full Text Available Many epidemics have broken out over the centuries. Hundreds and thousands of humans have died over a disease. Available treatments for infectious diseases have always been limited. Some infections are more deadly than the others, especially viral pathogens. These pathogens have continuously resisted all kinds of medical treatment, due to a need for new treatments to be developed. Drugs are present in nature and are also synthesized in vitro and they help in combating diseases and restoring health. Synthesizing drugs is a hard and time consuming task, which requires a lot of man power and financial aid. However, the natural compounds are just lying around on the earth, may it be land or water. Over a thousand novel compounds isolated from marine organisms are used as antiviral agents. Others are being pharmacologically tested. Today, over forty antiviral compounds are present in the pharmacological market. Some of these compounds are undergoing clinical and pre-clinical stages. Marine compounds are paving the way for a new trend in modern medicine.

  18. Dimerization of tetherin is not essential for its antiviral activity against Lassa and Marburg viruses.

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    Toshie Sakuma

    Full Text Available Tetherin (also known as BST2, CD317 or HM1.24 has recently been reported to inhibit a wide range of viruses. However, the antiviral mechanism of action of tetherin has not been determined. Both ends of the tetherin molecule are associated with the plasma membrane and it forms a homodimer. Therefore, a model in which progeny virions are retained on the cell surface by dimer formation between tetherin molecules on the viral envelope and plasma membrane has been proposed as the antiviral mechanism of action of this molecule. To investigate this possibility, we examined the correlation between dimerization and antiviral activity of tetherin in Lassa and Marburg virus-like particle production systems using tetherin mutants deficient in dimer formation. However, the tetherin mutant with complete loss of dimerization activity still showed apparent antiviral activity, indicating that dimerization of tetherin is not essential for its antiviral activity. This suggests that tetherin retains progeny virions on the cell surface by a mechanism other than dimerization.

  19. Structure activity relationship of dendrimer microbicides with dual action antiviral activity.

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    David Tyssen

    Full Text Available BACKGROUND: Topical microbicides, used by women to prevent the transmission of HIV and other sexually transmitted infections are urgently required. Dendrimers are highly branched nanoparticles being developed as microbicides. However, the anti-HIV and HSV structure-activity relationship of dendrimers comprising benzyhydryl amide cores and lysine branches, and a comprehensive analysis of their broad-spectrum anti-HIV activity and mechanism of action have not been published. METHODS AND FINDINGS: Dendrimers with optimized activity against HIV-1 and HSV-2 were identified with respect to the number of lysine branches (generations and surface groups. Antiviral activity was determined in cell culture assays. Time-of-addition assays were performed to determine dendrimer mechanism of action. In vivo toxicity and HSV-2 inhibitory activity were evaluated in the mouse HSV-2 susceptibility model. Surface groups imparting the most potent inhibitory activity against HIV-1 and HSV-2 were naphthalene disulfonic acid (DNAA and 3,5-disulfobenzoic acid exhibiting the greatest anionic charge and hydrophobicity of the seven surface groups tested. Their anti-HIV-1 activity did not appreciably increase beyond a second-generation dendrimer while dendrimers larger than two generations were required for potent anti-HSV-2 activity. Second (SPL7115 and fourth generation (SPL7013 DNAA dendrimers demonstrated broad-spectrum anti-HIV activity. However, SPL7013 was more active against HSV and blocking HIV-1 envelope mediated cell-to-cell fusion. SPL7013 and SPL7115 inhibited viral entry with similar potency against CXCR4-(X4 and CCR5-using (R5 HIV-1 strains. SPL7013 was not toxic and provided at least 12 h protection against HSV-2 in the mouse vagina. CONCLUSIONS: Dendrimers can be engineered with optimized potency against HIV and HSV representing a unique platform for the controlled synthesis of chemically defined multivalent agents as viral entry inhibitors. SPL7013 is

  20. Design and evaluation of novel interferon lambda analogs with enhanced antiviral activity and improved drug attributes.

    Science.gov (United States)

    Yu, Debin; Zhao, Mingzhi; Dong, Liwei; Zhao, Lu; Zou, Mingwei; Sun, Hetong; Zhang, Mengying; Liu, Hongyu; Zou, Zhihua

    2016-01-01

    Type III interferons (IFNs) (also called IFN-λ: IFN-λ1, IFN-λ2, IFN-λ3, and IFN-λ4) are critical players in the defense against viral infection of mucosal epithelial cells, where the activity of type I IFNs is weak, and unlike type I IFNs that are associated with severe and diverse side effects, type III IFNs cause minimal side effects due to the highly restricted expression of their receptors, and thus appear to be promising agents for the treatment and prevention of respiratory and gastrointestinal viral infection. However, the antiviral potency of natural type III IFNs is weak compared to type I and, although IFN-λ3 possesses the highest bioactivity among the type III IFNs, IFN-λ1, instead of IFN-λ3, is being developed as a therapeutic drug due to the difficulty to express IFN-λ3 in the prokaryotic expression system. Here, to develop optimal IFN-λ molecules with improved drug attributes, we designed a series of IFN-λ analogs by replacing critical amino acids of IFN-λ1 with the IFN-λ3 counterparts, and vice versa. Four of the designed analogs were successfully expressed in Escherichia coli with high yield and were easily purified from inclusion bodies. Interestingly, all four analogs showed potent activity in inducing the expression of the antiviral genes MxA and OAS and two of them, analog-6 and -7, displayed an unexpected high potency that is higher than that of type I IFN (IFN-α2a) in activating the IFN-stimulated response element (ISRE)-luciferase reporter. Importantly, both analog-6 and -7 effectively inhibited replication of hepatitis C virus in Huh-7.5.1 cells, with an IC50 that is comparable to that of IFN-α2a; and consistent with the roles of IFN-λ in mucosal epithelia, both analogs potently inhibited replication of H3N2 influenza A virus in A549 cells. Together, these studies identified two IFN-λ analogs as candidates to be developed as novel antiviral biologics.

  1. Design and evaluation of novel interferon lambda analogs with enhanced antiviral activity and improved drug attributes

    Science.gov (United States)

    Yu, Debin; Zhao, Mingzhi; Dong, Liwei; Zhao, Lu; Zou, Mingwei; Sun, Hetong; Zhang, Mengying; Liu, Hongyu; Zou, Zhihua

    2016-01-01

    Type III interferons (IFNs) (also called IFN-λ: IFN-λ1, IFN-λ2, IFN-λ3, and IFN-λ4) are critical players in the defense against viral infection of mucosal epithelial cells, where the activity of type I IFNs is weak, and unlike type I IFNs that are associated with severe and diverse side effects, type III IFNs cause minimal side effects due to the highly restricted expression of their receptors, and thus appear to be promising agents for the treatment and prevention of respiratory and gastrointestinal viral infection. However, the antiviral potency of natural type III IFNs is weak compared to type I and, although IFN-λ3 possesses the highest bioactivity among the type III IFNs, IFN-λ1, instead of IFN-λ3, is being developed as a therapeutic drug due to the difficulty to express IFN-λ3 in the prokaryotic expression system. Here, to develop optimal IFN-λ molecules with improved drug attributes, we designed a series of IFN-λ analogs by replacing critical amino acids of IFN-λ1 with the IFN-λ3 counterparts, and vice versa. Four of the designed analogs were successfully expressed in Escherichia coli with high yield and were easily purified from inclusion bodies. Interestingly, all four analogs showed potent activity in inducing the expression of the antiviral genes MxA and OAS and two of them, analog-6 and -7, displayed an unexpected high potency that is higher than that of type I IFN (IFN-α2a) in activating the IFN-stimulated response element (ISRE)-luciferase reporter. Importantly, both analog-6 and -7 effectively inhibited replication of hepatitis C virus in Huh-7.5.1 cells, with an IC50 that is comparable to that of IFN-α2a; and consistent with the roles of IFN-λ in mucosal epithelia, both analogs potently inhibited replication of H3N2 influenza A virus in A549 cells. Together, these studies identified two IFN-λ analogs as candidates to be developed as novel antiviral biologics. PMID:26792983

  2. Cytotoxic, Virucidal, and Antiviral Activity of South American Plant and Algae Extracts

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    Paula Faral-Tello

    2012-01-01

    Full Text Available Herpes simplex virus type 1 (HSV-1 infection has a prevalence of 70% in the human population. Treatment is based on acyclovir, valacyclovir, and foscarnet, three drugs that share the same mechanism of action and of which resistant strains have been isolated from patients. In this aspect, innovative drug therapies are required. Natural products offer unlimited opportunities for the discovery of antiviral compounds. In this study, 28 extracts corresponding to 24 plant species and 4 alga species were assayed in vitro to detect antiviral activity against HSV-1. Six of the methanolic extracts inactivated viral particles by direct interaction and 14 presented antiviral activity when incubated with cells already infected. Most interesting antiviral activity values obtained are those of Limonium brasiliense, Psidium guajava, and Phyllanthus niruri, which inhibit HSV-1 replication in vitro with 50% effective concentration (EC50 values of 185, 118, and 60 μg/mL, respectively. For these extracts toxicity values were calculated and therefore selectivity indexes (SI obtained. Further characterization of the bioactive components of antiviral plants will pave the way for the discovery of new compounds against HSV-1.

  3. Antiviral activity of Acacia nilotica against Hepatitis C Virus in liver infected cells

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    Javed Tariq

    2011-05-01

    Full Text Available Abstract Hepatitis C virus (HCV belonging to the family Flaviviridae has infected 3% of the population worldwide and 6% of the population in Pakistan. The only recommended standard treatment is pegylated INF-α plus ribavirin. Due to less compatibility of the standard treatment, thirteen medicinal plants were collected from different areas of Pakistan on the basis of undocumented antiviral reports against different viral infections. Medicinal plants were air dried, extracted and screened out against HCV by infecting HCV inoculums of 3a genotype in liver cells. RT-PCR results demonstrate that acetonic and methanolic extract of Acacia nilotica (AN showed more than 50% reduction at non toxic concentration. From the above results, it can be concluded that by selecting different molecular targets, specific structure-activity relationship can be achieved by doing mechanistic analysis. So, additional studies are required for the isolation and recognition of antiviral compound in AN to establish its importance as antiviral drug against HCV. For further research, we will scrutinize the synergistic effect of active antiviral compound in combination with standard PEG INF-α and ribavirin which may be helpful in exploring further gateways for antiviral therapy against HCV.

  4. Egyptian propolis: 2. Chemical composition, antiviral and antimicrobial activities of East Nile Delta propolis.

    Science.gov (United States)

    Abd El Hady, Faten K; Hegazi, Ahmed G

    2002-01-01

    Three propolis samples from East Nile Delta, Egypt were collected. Propolis samples were investigated by GC/MS,103 compounds were identified, 20 being new for propolis. Dakahlia propolis was a typical poplar propolis but it contained two new caffeate esters and two new triterpenoids. Ismailia propolis was characterized by the presence of new triterpenic acid methyl esters and it did not contain any aromatic acids, esters and flavonoids. Sharkia propolis was characterized by the presence of caffeate esters only, some di- and triterpenoids. The antiviral (Infectious Bursal Disease Virus and Reo-Virus) and antimicrobial (Staphylococcus aureus; Escherichia coli and Candida albicans) activities of propolis samples were investigated. Dakahlia propolis showed the highest antiviral activity against Infectious Bursal Disease Virus (IBDV) and the highest antibacterial activity against Escherichia coli and the highest antifungal activity against Candida albicans. While Ismailia propolis had the highest antiviral activity against Reo-virus. Sharkia propolis showed the highest antibacterial activity against Staphylococcus aureus and moderate antiviral activity against infectious bursal disease virus and reovirus.

  5. Antiviral activity of the EB peptide against zoonotic poxviruses

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    Altmann Sharon E

    2012-01-01

    Full Text Available Abstract Background The EB peptide is a 20-mer that was previously shown to have broad spectrum in vitro activity against several unrelated viruses, including highly pathogenic avian influenza, herpes simplex virus type I, and vaccinia, the prototypic orthopoxvirus. To expand on this work, we evaluated EB for in vitro activity against the zoonotic orthopoxviruses cowpox and monkeypox and for in vivo activity in mice against vaccinia and cowpox. Findings In yield reduction assays, EB had an EC50 of 26.7 μM against cowpox and 4.4 μM against monkeypox. The EC50 for plaque reduction was 26.3 μM against cowpox and 48.6 μM against monkeypox. A scrambled peptide had no inhibitory activity against either virus. EB inhibited cowpox in vitro by disrupting virus entry, as evidenced by a reduction of the release of virus cores into the cytoplasm. Monkeypox was also inhibited in vitro by EB, but at the attachment stage of infection. EB showed protective activity in mice infected intranasally with vaccinia when co-administered with the virus, but had no effect when administered prophylactically one day prior to infection or therapeutically one day post-infection. EB had no in vivo activity against cowpox in mice. Conclusions While EB did demonstrate some in vivo efficacy against vaccinia in mice, the limited conditions under which it was effective against vaccinia and lack of activity against cowpox suggest EB may be more useful for studying orthopoxvirus entry and attachment in vitro than as a therapeutic against orthopoxviruses in vivo.

  6. Evaluation of antiviral and cytotoxic activities of methanolic extract of S. grandiflora (Fabaceae) flowers

    Institute of Scientific and Technical Information of China (English)

    Saravana Kumar Arthanari; Jayachandran Vanitha; Mani Ganesh; Krishnasamy Venkateshwaran; De Clercq

    2012-01-01

    Objective: To investigate the cytotoxicity and antiviral activity of methanolic extract of S.grandiflora flowers using different cell lines and viruses. Methods: The methanolic flower extracts were prepared and evaluated for their antiviral and cytotoxic activities using viruses like herpes simplex-1 and 2, vaccinia, vesicular stomatitis, cox sackie, respiratory syncytical, feline corona, feline herpes, para influenza, reo-1, sindbis and punta toro viruses in different cell lines, like Hel, HeLa, Crandell Reus feline kidney and Vero cell cultures. Results: Among the viruses used the extract possessed strongest antiviral activity against herpes simplex 1 and 2, repiratory syncytical, para influenza, reo, sindbis, cox sackie and punta toro viruses that was (EC50=20 μg/mL and 45 μg/mL) and moderate activity for remaining viruses (EC50= 100 μg/mL). The antiviral activities assessed by calculating the selectivity index may be due to the presence of flavonoids in the extracts there by inhibit the virus cell fusion in the early and replication stages. The cytotoxicity effect was evaluated using MTT assay and the results revealed that the extracts exhibited cytotoxicity from the range of 20 to 100 μg/mL. Conclusions: Present results confirmed that the S. grandiflora used as a good antimicrobial agent in future.

  7. Phytochemical screening, cytotoxicity and antiviral activity of hexane fraction of Phaleria macrocarpa fruits

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    Ismaeel, Mahmud Yusef Yusef; Yaacob, Wan Ahmad; Tahir, Mariya Mohd.; Ibrahim, Nazlina

    2015-09-01

    Phaleria macrocarpa fruits have been widely used in the traditional medicine for the treatment of several infections. The current study was done to determine the phytochemical content, cytotoxicity and antiviral activity of the hexane fraction (HF) of P. macrocarpa fruits. In the hexane fraction of P. macarocarpa fruits, phytochemical screening showed the presence of terpenoids whereas saponins, alkaloids, tannins and anthraquinones were not present. Evaluation on Vero cell lines by using MTT assay showed that the 50% cytotoxic concentration (CC50) value was 0.48 mg/mL indicating that the fraction is not cytotoxic. Antiviral properties of the plant extracts were determined by plaque reduction assay. The effective concentration (EC50) was 0.18 mg/mL. Whereas the selective index (SI = CC50/EC50) of hexane fraction is 2.6 indicating low to moderate potential as antiviral agent.

  8. A systemic resistance inducing antiviral protein with N-glycosidase activity from Bougainvillea xbuttiana leaves.

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    Narwal, S; Balasubrahmanyam, A; Sadhna, P; Kapoor, H; Lodha, M L

    2001-06-01

    An antiviral protein from Bougainvillea xbuttiana leaves induced systemic resistance in host plants N. glutinosa and Cyamopsis tetragonoloba against TMV and SRV, respectively which was reversed by actinomycin D, when applied immediately or shortly after antiviral protein treatment. When the inhibitor was applied to the host plant leaves post inoculation, it was effective if applied upto 4 h after virus infection. It also delayed the expression of symptoms in systemic hosts of TMV. The inhibitor showed characteristic N-glycosidase activity on 25S rRNA of tobacco ribosomes, suggesting that it could also be interfering with virus multiplication through ribosome-inactivation process.

  9. Genome-wide analysis of antiviral signature genes in porcine macrophages at different activation statuses.

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    Yongming Sang

    Full Text Available Macrophages (MФs can be polarized to various activation statuses, including classical (M1, alternative (M2, and antiviral states. To study the antiviral activation status of porcine MФs during porcine reproductive and respiratory syndrome virus (PRRSV infection, we used RNA Sequencing (RNA-Seq for transcriptomic analysis of differentially expressed genes (DEGs. Sequencing assessment and quality evaluation showed that our RNA-Seq data met the criteria for genome-wide transcriptomic analysis. Comparisons of any two activation statuses revealed more than 20,000 DEGs that were normalized to filter out 153-5,303 significant DEGs [false discovery rate (FDR ≤0.001, fold change ≥2] in each comparison. The highest 5,303 significant DEGs were found between lipopolysaccharide- (LPS and interferon (IFNγ-stimulated M1 cells, whereas only 153 significant DEGs were detected between interleukin (IL-10-polarized M2 cells and control mock-activated cells. To identify signature genes for antiviral regulation pertaining to each activation status, we identified a set of DEGs that showed significant up-regulation in only one activation state. In addition, pathway analyses defined the top 20-50 significantly regulated pathways at each activation status, and we further analyzed DEGs pertinent to pathways mediated by AMP kinase (AMPK and epigenetic mechanisms. For the first time in porcine macrophages, our transcriptomic analyses not only compared family-wide differential expression of most known immune genes at different activation statuses, but also revealed transcription evidence of multiple gene families. These findings show that using RNA-Seq transcriptomic analyses in virus-infected and status-synchronized macrophages effectively profiled signature genes and gene response pathways for antiviral regulation, which may provide a framework for optimizing antiviral immunity and immune homeostasis.

  10. Design and evaluation of novel interferon lambda analogs with enhanced antiviral activity and improved drug attributes

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    Yu D

    2016-01-01

    Full Text Available Debin Yu,1 Mingzhi Zhao,2 Liwei Dong,1 Lu Zhao,1 Mingwei Zou,3 Hetong Sun,4 Mengying Zhang,4 Hongyu Liu,4 Zhihua Zou1 1National Engineering Laboratory for AIDS Vaccine, Key Laboratory for Molecular Enzymology and Engineering of the Ministry of Education, School of Life Sciences, Jilin University, Changchun, 2State Key Laboratory of Proteomics, National Engineering Research Center for Protein Drugs, Beijing Proteome Research Center, Beijing Institute of Radiation Medicine, Beijing, People’s Republic of China; 3Department of Psychology, College of Liberal Arts and Social Sciences, University of Houston, Houston, TX, USA; 4Prosit Sole Biotechnology, Co., Ltd., Beijing, People’s Republic of China Abstract: Type III interferons (IFNs (also called IFN-λ: IFN-λ1, IFN-λ2, IFN-λ3, and IFN-λ4 are critical players in the defense against viral infection of mucosal epithelial cells, where the activity of type I IFNs is weak, and unlike type I IFNs that are associated with severe and diverse side effects, type III IFNs cause minimal side effects due to the highly restricted expression of their receptors, and thus appear to be promising agents for the treatment and prevention of respiratory and gastrointestinal viral infection. However, the antiviral potency of natural type III IFNs is weak compared to type I and, although IFN-λ3 possesses the highest bioactivity among the type III IFNs, IFN-λ1, instead of IFN-λ3, is being developed as a therapeutic drug due to the difficulty to express IFN-λ3 in the prokaryotic expression system. Here, to develop optimal IFN-λ molecules with improved drug attributes, we designed a series of IFN-λ analogs by replacing critical amino acids of IFN-λ1 with the IFN-λ3 counterparts, and vice versa. Four of the designed analogs were successfully expressed in Escherichia coli with high yield and were easily purified from inclusion bodies. Interestingly, all four analogs showed potent activity in inducing the

  11. Coxsackievirus cloverleaf RNA containing a 5' triphosphate triggers an antiviral response via RIG-I activation.

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    Qian Feng

    Full Text Available Upon viral infections, pattern recognition receptors (PRRs recognize pathogen-associated molecular patterns (PAMPs and stimulate an antiviral state associated with the production of type I interferons (IFNs and inflammatory markers. Type I IFNs play crucial roles in innate antiviral responses by inducing expression of interferon-stimulated genes and by activating components of the adaptive immune system. Although pegylated IFNs have been used to treat hepatitis B and C virus infections for decades, they exert substantial side effects that limit their use. Current efforts are directed toward the use of PRR agonists as an alternative approach to elicit host antiviral responses in a manner similar to that achieved in a natural infection. RIG-I is a cytosolic PRR that recognizes 5' triphosphate (5'ppp-containing RNA ligands. Due to its ubiquitous expression profile, induction of the RIG-I pathway provides a promising platform for the development of novel antiviral agents and vaccine adjuvants. In this study, we investigated whether structured RNA elements in the genome of coxsackievirus B3 (CVB3, a picornavirus that is recognized by MDA5 during infection, could activate RIG-I when supplied with 5'ppp. We show here that a 5'ppp-containing cloverleaf (CL RNA structure is a potent RIG-I inducer that elicits an extensive antiviral response that includes induction of classical interferon-stimulated genes, as well as type III IFNs and proinflammatory cytokines and chemokines. In addition, we show that prophylactic treatment with CVB3 CL provides protection against various viral infections including dengue virus, vesicular stomatitis virus and enterovirus 71, demonstrating the antiviral efficacy of this RNA ligand.

  12. Antiviral activity of KR-23502 targeting nuclear export of influenza B virus ribonucleoproteins.

    Science.gov (United States)

    Jang, Yejin; Lee, Hye Won; Shin, Jin Soo; Go, Yun Young; Kim, Chonsaeng; Shin, Daeho; Malpani, Yashwardhan; Han, Soo Bong; Jung, Young-Sik; Kim, Meehyein

    2016-10-01

    The spiro compound 5,6-dimethyl-3H,3'H-spiro(benzofuran-2,1'-isobenzofuran)-3,3'-dione (KR-23502) has antiviral activity against influenza A and more potently B viruses. The aim of this study is to elucidate its mechanism of action. Subcellular localization and time-course expression of influenza B viral proteins, nucleoprotein (NP) and matrix protein 1 (M1), showed that KR-23502 reduced their amounts within 5 h post-infection. Early steps of virus life cycle, including virus entry, nuclear localization of NP and viral RNA-dependent RNA replication, were not affected by KR-23502. Instead it interrupted a later event corresponding to nuclear export of NP and M1 proteins. Delivery of viral ribonucleoprotein (vRNP)-M1 complex has been known to be mediated by the viral nuclear export protein (NEP) through interaction with cellular chromosomal maintenance 1 (CRM1) protein. In this study, we experimentally demonstrated that the compound targets the nuclear export of vRNP. Moreover, a single mutation (aspartate to glycine) at amino acid position 54 in M1 [M1(D54G)] was detected after 18 passages in the presence of KR-23502 with a 2-fold increase in 50% effective concentration indicating that this compound has a relatively high genetic barrier to resistance. Interestingly, it was observed that proteasome-mediated degradation of M1(D54G) was attenuated by KR-23502. In conclusion, we suggest that KR-23502 shows its anti-influenza activity by downregulating NEP/CRM1-mediated nuclear export of influenza vRNP and M1. KR-23502 provides a core chemical skeleton for further structure-based design of novel antivirals against influenza viruses. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Cytotoxicity, antiviral and antimicrobial activities of alkaloids, flavonoids, and phenolic acids.

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    Ozçelik, Berrin; Kartal, Murat; Orhan, Ilkay

    2011-04-01

    Some natural products consisting of the alkaloids yohimbine and vincamine (indole-type), scopolamine and atropine (tropane-type), colchicine (tropolone-type), allantoin (imidazolidine-type), trigonelline (pyridine-type) as well as octopamine, synephrine, and capsaicin (exocyclic amine-type); the flavonoid derivatives quercetin, apigenin, genistein, naringin, silymarin, and silibinin; and the phenolic acids namely gallic acid, caffeic acid, chlorogenic acid, and quinic acid, were tested for their in vitro antiviral, antibacterial, and antifungal activities and cytotoxicity. Antiviral activity of the compounds was tested against DNA virus herpes simplex type 1 and RNA virus parainfluenza (type-3). Cytotoxicity of the compounds was determined using Madin-Darby bovine kidney and Vero cell lines, and their cytopathogenic effects were expressed as maximum non-toxic concentration. Antibacterial activity was assayed against following bacteria and their isolated strains: Escherichia coli, Pseudomonas aeruginosa, Proteus mirabilis, Klebsiella pneumoniae, Acinetobacter baumannii, Staphylococcus aureus, Enterococcus faecalis, and Bacillus subtilis, although they were screened by microdilution method against two fungi: Candida albicans and Candida parapsilosis. Atropine and gallic acid showed potent antiviral effect at the therapeutic range of 0.8-0.05 µg ml(-1), whilst all of the compounds exerted robust antibacterial effect. Antiviral and antimicrobial effects of the compounds tested herein may constitute a preliminary step for further relevant studies to identify the mechanism of action.

  14. Antiviral Activity of MK-4965, a Novel Nonnucleoside Reverse Transcriptase Inhibitor▿

    Science.gov (United States)

    Lai, Ming-Tain; Munshi, Vandna; Touch, Sinoeun; Tynebor, Robert M.; Tucker, Thomas J.; McKenna, Philip M.; Williams, Theresa M.; DiStefano, Daniel J.; Hazuda, Daria J.; Miller, Michael D.

    2009-01-01

    Nonnucleoside reverse transcriptase inhibitors (NNRTIs) are the mainstays of therapy for the treatment of human immunodeficiency virus type 1 (HIV-1) infections. However, the effectiveness of NNRTIs can be hampered by the development of resistance mutations which confer cross-resistance to drugs in the same class. Extensive efforts have been made to identify new NNRTIs that can suppress the replication of the prevalent NNRTI-resistant viruses. MK-4965 is a novel NNRTI that possesses both diaryl ether and indazole moieties. The compound displays potency at subnanomolar concentrations against wild-type (WT), K103N, and Y181C reverse transcriptase (RT) in biochemical assays. MK-4965 is also highly potent against the WT virus and two most prevalent NNRTI-resistant viruses (viruses that harbor the K103N or the Y181C mutation), against which it had 95% effective concentrations (EC95s) of <30 nM in the presence of 10% fetal bovine serum. The antiviral EC95 of MK-4965 was reduced approximately four- to sixfold when it was tested in 50% human serum. Moreover, MK-4965 was evaluated with a panel of 15 viruses with NNRTI resistance-associated mutations and showed a superior mutant profile to that of efavirenz but not to that of etravirine. MK-4965 was similarly effective against various HIV-1 subtypes and viruses containing nucleoside reverse transcriptase inhibitor or protease inhibitor resistance-conferring mutations. A two-drug combination study showed that the antiviral activity of MK-4965 was nonantagonistic with each of the 18 FDA-licensed drugs tested vice versa in the present study. Taken together, these in vitro data show that MK-4965 possesses the desired properties for further development as a new NNRTI for the treatment of HIV-1 infection. PMID:19289522

  15. Tannic acid modified silver nanoparticles show antiviral activity in herpes simplex virus type 2 infection.

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    Piotr Orlowski

    Full Text Available The interaction between silver nanoparticles and herpesviruses is attracting great interest due to their antiviral activity and possibility to use as microbicides for oral and anogenital herpes. In this work, we demonstrate that tannic acid modified silver nanoparticles sized 13 nm, 33 nm and 46 nm are capable of reducing HSV-2 infectivity both in vitro and in vivo. The antiviral activity of tannic acid modified silver nanoparticles was size-related, required direct interaction and blocked virus attachment, penetration and further spread. All tested tannic acid modified silver nanoparticles reduced both infection and inflammatory reaction in the mouse model of HSV-2 infection when used at infection or for a post-infection treatment. Smaller-sized nanoparticles induced production of cytokines and chemokines important for anti-viral response. The corresponding control buffers with tannic acid showed inferior antiviral effects in vitro and were ineffective in blocking in vivo infection. Our results show that tannic acid modified silver nanoparticles are good candidates for microbicides used in treatment of herpesvirus infections.

  16. Cloning and characterization of the antiviral activity of feline Tetherin/BST-2.

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    Aiko Fukuma

    Full Text Available Human Tetherin/BST-2 has recently been identified as a cellular antiviral factor that blocks the release of various enveloped viruses. In this study, we cloned a cDNA fragment encoding a feline homolog of Tetherin/BST-2 and characterized the protein product. The degree of amino acid sequence identity between human Tetherin/BST-2 and the feline homolog was 44.4%. Similar to human Tetherin/BST-2, the expression of feline Tetherin/BST-2 mRNA was inducible by type I interferon (IFN. Exogenous expression of feline Tetherin/BST-2 efficiently inhibited the release of feline endogenous retrovirus RD-114. The extracellular domain of feline Tetherin/BST-2 has two putative N-linked glycosylation sites, N79 and N119. Complete loss of N-linked glycosylation by introduction of mutations into both sites resulted in almost complete abolition of its antiviral activity. In addition, feline Tetherin/BST-2 was insensitive to antagonism by HIV-1 Vpu, although the antiviral activity of human Tetherin/BST-2 was antagonized by HIV-1 Vpu. Our data suggest that feline Tetherin/BST-2 functions as a part of IFN-induced innate immunity against virus infection and that the induction of feline Tetherin/BST-2 in vivo may be effective as a novel antiviral strategy for viral infection.

  17. Synthesis, in vitro and in vivo antitumor and antiviral activity of novel 1-substituted benzimidazole derivatives.

    Science.gov (United States)

    Shaker, Yasser M; Omar, Mohamed A; Mahmoud, Khaled; Elhallouty, Salwa M; El-Senousy, Waled M; Ali, Mamdouh M; Mahmoud, Abeer E; Abdel-Halim, Abeer H; Soliman, Saeed M; El Diwani, Hoda I

    2015-01-01

    A novel series of 5-nitro-1H-benzimidazole derivatives substituted at position 1 by heterocyclic rings was synthesized. Cytotoxicity and antiviral activity of the new compounds were tested. Compound 3 was more active than doxorubicin against A-549, HCT-116 and MCF-7. However, compound 3 showed no activity against human liver carcinoma Hep G-2 cell line. Compounds 9 and 17b (E) showed potency near to doxorubicin against the four cell lines. The acute toxicity of compound 9 on liver cancer induced in rats was determined in vivo. Interestingly, it showed restoration activity of liver function and pathology towards normal as compared to the cancer-bearing rats induced by DENA. Compounds 17a (Z), 17b (E) and 18a (Z) were the most promising compounds for their antiviral activity against rotavirus Wa strain.

  18. Investigation of medicinal plants of togo for antiviral and antimicrobial activities.

    Science.gov (United States)

    Anani, K; Hudson, J B; de Souza, C; Akpagana, K; Tower, G H; Arnason, J T; Gbeassor, M

    2000-01-01

    Methanol extracts were prepared from 19 medicinal plants of Togo and, by means of standard laboratory tests, were analysed for antiviral and antibiotic activities. Ten of the 19 showed significant antiviral activity and all but two displayed antibiotic activity. Extracts of three species, Adansonia digitata (the most potent), Conyza aegyptiaca and Palisota hirsuta , were active against all three test viruses (herpes simplex, Sindbis and poliovirus). The other seven, however, were more selective, showing activity against only one or two viruses. The antibiotic profiles varied considerably. The observation that each extract showed a distinctive permutation of target organisms suggests that different bioactive phytochemicals are present in each species. Only two of the extracts were devoid of bioactivity.

  19. Antiviral activity of the Lippia graveolens (Mexican oregano essential oil and its main compound carvacrol against human and animal viruses

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    Marciele Ribas Pilau

    2011-12-01

    Full Text Available Mexican oregano (Lippia graveolens is a plant found in Mexico and Central America that is traditionally used as a medicinal herb. In the present study, we investigated the antiviral activity of the essential oil of Mexican oregano and its major component, carvacrol, against different human and animal viruses. The MTT test (3-4,5-dimethythiazol-2yl-2,5-diphenyl tetrazolium bromide was conducted to determine the selectivity index (SI of the essential oil, which was equal to 13.1, 7.4, 10.8, 9.7, and 7.2 for acyclovir-resistant herpes simplex virus type 1 (ACVR-HHV-1, acyclovir-sensitive HHV-1, human respiratory syncytial virus (HRSV, bovine herpesvirus type 2 (BoHV-2, and bovine viral diarrhoea virus (BVDV, respectively. The human rotavirus (RV and BoHV-1 and 5 were not inhibited by the essential oil. Carvacrol alone exhibited high antiviral activity against RV with a SI of 33, but it was less efficient than the oil for the other viruses. Thus, Mexican oregano oil and its main component, carvacrol, are able to inhibit different human and animal viruses in vitro. Specifically, the antiviral effects of Mexican oregano oil on ACVR-HHV-1 and HRSV and of carvacrol on RV justify more detailed studies.

  20. RNA interference screening of interferon-stimulated genes with antiviral activities against classical swine fever virus using a reporter virus.

    Science.gov (United States)

    Wang, Xiao; Li, Yongfeng; Li, Lian-Feng; Shen, Liang; Zhang, Lingkai; Yu, Jiahui; Luo, Yuzi; Sun, Yuan; Li, Su; Qiu, Hua-Ji

    2016-04-01

    Classical swine fever (CSF) caused by classical swine fever virus (CSFV) is a highly contagious and often fatal disease of pigs, which leads to significant economic losses in many countries. Viral infection can induce the production of interferons (IFNs), giving rise to the transcription of hundreds of IFN-stimulated genes (ISGs) to exert antiviral effects. Although numerous ISGs have been identified to possess antiviral activities against different viruses, rare anti-CSFV ISGs have been reported to date. In this study, to screen anti-CSFV ISGs, twenty-one ISGs reported previously were individually knocked down using small interfering RNAs (siRNAs) followed by infection with a reporter CSFV expressing Renilla luciferase (Rluc). As a result, four novel anti-CSFV ISGs were identified, including natural-resistance-associated macrophage protein 1 (NRAMP1), cytosolic 5'-nucleotidase III A (NT5C3A), chemokine C-X-C motif ligand 10 (CXCL10), and 2'-5'-oligoadenylate synthetase 1 (OAS1), which were further verified to exhibit antiviral activities against wild-type CSFV. We conclude that the reporter virus is a useful tool for efficient screening anti-CSFV ISGs.

  1. Amphipathic DNA polymers exhibit antiviral activity against systemic Murine Cytomegalovirus infection

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    Juteau Jean-Marc

    2009-12-01

    Full Text Available Abstract Background Phosphorothioated oligonucleotides (PS-ONs have a sequence-independent, broad spectrum antiviral activity as amphipathic polymers (APs and exhibit potent in vitro antiviral activity against a broad spectrum of herpesviruses: HSV-1, HSV-2, HCMV, VZV, EBV, and HHV-6A/B, and in vivo activity in a murine microbiocide model of genital HSV-2 infection. The activity of these agents against animal cytomegalovirus (CMV infections in vitro and in vivo was therefore investigated. Results In vitro, a 40 mer degenerate AP (REP 9 inhibited both murine CMV (MCMV and guinea pig CMV (GPCMV with an IC50 of 0.045 μM and 0.16 μM, respectively, and a 40 mer poly C AP (REP 9C inhibited MCMV with an IC50 of 0.05 μM. Addition of REP 9 to plaque assays during the first two hours of infection inhibited 78% of plaque formation whereas addition of REP 9 after 10 hours of infection did not significantly reduce the number of plaques, indicating that REP 9 antiviral activity against MCMV occurs at early times after infection. In a murine model of CMV infection, systemic treatment for 5 days significantly reduced virus replication in the spleens and livers of infected mice compared to saline-treated control mice. REP 9 and REP 9C were administered intraperitoneally for 5 consecutive days at 10 mg/kg, starting 2 days prior to MCMV infection. Splenomegaly was observed in infected mice treated with REP 9 but not in control mice or in REP 9 treated, uninfected mice, consistent with mild CpG-like activity. When REP 9C (which lacks CpG motifs was compared to REP 9, it exhibited comparable antiviral activity as REP 9 but was not associated with splenomegaly. This suggests that the direct antiviral activity of APs is the predominant therapeutic mechanism in vivo. Moreover, REP 9C, which is acid stable, was effective when administered orally in combination with known permeation enhancers. Conclusion These studies indicate that APs exhibit potent, well tolerated

  2. Molecular characterization and antiviral activity test of common drugs against echovirus 18 isolated in Korea

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    Park KwiSung

    2011-11-01

    Full Text Available Abstract Genetic diversity and antiviral activity for five common antiviral drugs of echovirus (ECV 5 isolated in Korea have been described. The present study extended these tests to a Korean ECV 18 isolate. An outbreak of aseptic meningitis caused by the ECV 18 isolate was reported in Korea in 2005, marking the first time this virus had been identified in the country since enterovirus surveillance began in 1993. Using a sample isolated from stool specimen of a 5-year-old male patient with aseptic meningitis, the complete genome sequence was obtained and was compared it with the Metcalf prototype strain. Unlike the ECV5 isolate, the 3' untranslated region had the highest identity value (94.2% at the nucleotide level, while, at the amino acid level, the P2 region displayed the highest identity value (96.9%. These two strains shared all cleavage sites, with the exception of the 2B/2C site, which was RQ/NN in the Metcalf strain but RQ/NS in the Korean ECV 18 isolate. In Vero cells infected with the Korean ECV 18 isolate, no cytotoxicity was observed in the presence of azidothymidine, acyclovir, amantadine, lamivudine, or ribavirin, when the drugs were administered at a CC50 value >100 μg/mL. Of the five drugs, only amantadine (IC50: 4.97 ± 0.77 μg/mL, TI: 20.12 and ribavirin (IC50: 7.63 ± 0.87 μg/mL, TI: 13.11 had any antiviral activity against the Korean ECV 18 isolate in the five antiviral drugs. These antiviral activity effects were similar with results of the Korean ECV5 isolate.

  3. [Antiviral activity of different drugs in vitro against viruses of bovine infectious rhinotracheitis and bovine diarrhea].

    Science.gov (United States)

    Glotov, A G; Glotova, T I; Sergeev, A A; Belkina, T V; Sergeev, A N

    2004-01-01

    In vitro experiments studied the antiviral activity of 11 different drugs against viruses of bovine infective rhinotracheitis (BIRT) and bovine viral diarrhea (BVD). The 50% inhibiting concentrations of the test agents were determined in the monolayers of MDBK and KCT cell cultures. Only did phosprenyl show a virucidal activity against BIRT virus. All the tested drugs significantly inhibited the reproduction of BIRT virus in the sensitive MDBK cell cultures. Thus, bromuridin, acyclovir, ribavirin and methisazonum inhibited the virus by > or = 100,000 times; liposomal ribavirin, gossypolum, anandinum, polyprenolum, phosprenyl, by 1000-10,000 times; eracond and argovit, by 100 times. In experiments on BVD virus, the cultured KCT cells displayed the antiviral activity of bromuridin, phosprenil, polyprenolum, methisazonum, acyclovir, gossypolum, argovit, and ribavirin (in two variants), which caused a statistically significant (100-10,000-fold) decrease in the productive activity of this virus. Eracond and anandid proved to be ineffective.

  4. Synthesis and antiviral activities of a novel class of thioflavone and flavonoid analogues

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    Dajun Zhang

    2012-12-01

    Full Text Available A novel class of thioflavone and flavonoid derivatives has been prepared and their antiviral activities against enterovirus 71 (EV71 and the coxsackievirus B3 (CVB3 and B6 (CVB6 were evaluated. Compounds 7d and 9b showed potent antiviral activities against EV71 with IC50 values of 8.27 and 5.48 μM, respectively. Compound 7f, which has been synthesized for the first time in this work, showed the highest level of inhibitory activity against both CVB3 and CVB6 with an IC50 value of 0.62 and 0.87 μM. Compounds 4b, 7a, 9c and 9e also showed strong inhibitory activities against both the CVB3 and CVB6 at low concentrations (IC50=1.42−7.15 μM, whereas compounds 4d, 7c, 7e and 7g showed strong activity against CVB6 (IC50=2.91–3.77 μM together with low levels of activity against CVB3. Compound 7d exhibited stronger inhibitory activity against CVB3 (IC50=6.44 μM than CVB6 (IC50>8.29 μM. The thioflavone derivatives 7a, 7c, 7d, 7e, 7f and 7g, represent a new class of lead compounds for the development of novel antiviral agents.

  5. Antibody complementarity-determining regions (CDRs can display differential antimicrobial, antiviral and antitumor activities.

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    Luciano Polonelli

    Full Text Available BACKGROUND: Complementarity-determining regions (CDRs are immunoglobulin (Ig hypervariable domains that determine specific antibody (Ab binding. We have shown that synthetic CDR-related peptides and many decapeptides spanning the variable region of a recombinant yeast killer toxin-like antiidiotypic Ab are candidacidal in vitro. An alanine-substituted decapeptide from the variable region of this Ab displayed increased cytotoxicity in vitro and/or therapeutic effects in vivo against various bacteria, fungi, protozoa and viruses. The possibility that isolated CDRs, represented by short synthetic peptides, may display antimicrobial, antiviral and antitumor activities irrespective of Ab specificity for a given antigen is addressed here. METHODOLOGY/PRINCIPAL FINDINGS: CDR-based synthetic peptides of murine and human monoclonal Abs directed to: a a protein epitope of Candida albicans cell wall stress mannoprotein; b a synthetic peptide containing well-characterized B-cell and T-cell epitopes; c a carbohydrate blood group A substance, showed differential inhibitory activities in vitro, ex vivo and/or in vivo against C. albicans, HIV-1 and B16F10-Nex2 melanoma cells, conceivably involving different mechanisms of action. Antitumor activities involved peptide-induced caspase-dependent apoptosis. Engineered peptides, obtained by alanine substitution of Ig CDR sequences, and used as surrogates of natural point mutations, showed further differential increased/unaltered/decreased antimicrobial, antiviral and/or antitumor activities. The inhibitory effects observed were largely independent of the specificity of the native Ab and involved chiefly germline encoded CDR1 and CDR2 of light and heavy chains. CONCLUSIONS/SIGNIFICANCE: The high frequency of bioactive peptides based on CDRs suggests that Ig molecules are sources of an unlimited number of sequences potentially active against infectious agents and tumor cells. The easy production and low cost of small

  6. Antibody Complementarity-Determining Regions (CDRs) Can Display Differential Antimicrobial, Antiviral and Antitumor Activities

    Science.gov (United States)

    Polonelli, Luciano; Pontón, José; Elguezabal, Natalia; Moragues, María Dolores; Casoli, Claudio; Pilotti, Elisabetta; Ronzi, Paola; Dobroff, Andrey S.; Rodrigues, Elaine G.; Juliano, Maria A.; Maffei, Domenico Leonardo; Magliani, Walter; Conti, Stefania; Travassos, Luiz R.

    2008-01-01

    Background Complementarity-determining regions (CDRs) are immunoglobulin (Ig) hypervariable domains that determine specific antibody (Ab) binding. We have shown that synthetic CDR-related peptides and many decapeptides spanning the variable region of a recombinant yeast killer toxin-like antiidiotypic Ab are candidacidal in vitro. An alanine-substituted decapeptide from the variable region of this Ab displayed increased cytotoxicity in vitro and/or therapeutic effects in vivo against various bacteria, fungi, protozoa and viruses. The possibility that isolated CDRs, represented by short synthetic peptides, may display antimicrobial, antiviral and antitumor activities irrespective of Ab specificity for a given antigen is addressed here. Methodology/Principal Findings CDR-based synthetic peptides of murine and human monoclonal Abs directed to: a) a protein epitope of Candida albicans cell wall stress mannoprotein; b) a synthetic peptide containing well-characterized B-cell and T-cell epitopes; c) a carbohydrate blood group A substance, showed differential inhibitory activities in vitro, ex vivo and/or in vivo against C. albicans, HIV-1 and B16F10-Nex2 melanoma cells, conceivably involving different mechanisms of action. Antitumor activities involved peptide-induced caspase-dependent apoptosis. Engineered peptides, obtained by alanine substitution of Ig CDR sequences, and used as surrogates of natural point mutations, showed further differential increased/unaltered/decreased antimicrobial, antiviral and/or antitumor activities. The inhibitory effects observed were largely independent of the specificity of the native Ab and involved chiefly germline encoded CDR1 and CDR2 of light and heavy chains. Conclusions/Significance The high frequency of bioactive peptides based on CDRs suggests that Ig molecules are sources of an unlimited number of sequences potentially active against infectious agents and tumor cells. The easy production and low cost of small sized synthetic

  7. Antiviral and antimicrobial activities of three sesquiterpene lactones from Centaurea solstitialis L. ssp. solstitialis.

    Science.gov (United States)

    Ozçelik, Berrin; Gürbüz, Ilhan; Karaoglu, Taner; Yeşilada, Erdem

    2009-01-01

    Three sesquiterpene lactones (centaurepensin = chlorohyssopifolin A, chlorojanerin and 13-acetyl solstitialin A) isolated from the aerial parts of Centaurea solstitialis L. ssp. solstitialis (Asteraceae) were investigated for antimicrobial and antiviral activities. For the antimicrobial activity assessment, both standard and isolated strains of Escherichia coli, Pseudomonas aeruginosa, Enterococcus faecalis, Staphylococcus aureus, Candida albicans and C. parapsilosis were employed by the microdilution method. Herpes simplex type-1, a DNA virus, and Parainfluenza, an RNA virus, were employed for the determination of the antiviral activity of these three sesquiterpene lactones using Vero cell lines. Ampicilline, ofloxocine, ketoconazole, fluconazole, acyclovir and oseltamivir were used as the reference drugs. 13-Acetyl solstitialin A displayed remarkable antibacterial activity against isolated strains of E. faecalis at 1 microg/ml concentration, which was close to the effective concentrations of ampicillin. The same compound also showed significant activity against the DNA virus, being as potent as the reference compound acyclovir at maximum and minimum concentrations of 16-<0.00006 microg/ml. This is the first report showing that 13-acetyl solstitialin A possesses significant antiviral activity.

  8. Antiviral activity of Plantago major extracts and related compounds in vitro.

    Science.gov (United States)

    Chiang, L C; Chiang, W; Chang, M Y; Ng, L T; Lin, C C

    2002-07-01

    Plantago major L., a popular traditional Chinese medicine, has long been used for treating various diseases varying from cold to viral hepatitis. The aim of present study was to examine the antiviral activity of aqueous extract and pure compounds of P. major. Studies were conducted on a series of viruses, namely herpesviruses (HSV-1, HSV-2) and adenoviruses (ADV-3, ADV-8, ADV-11). The antiviral activity of EC50 was defined as the concentration achieved 50% cyto-protection against virus infection and the selectivity index (SI) was determined by the ratio of CC50 (concentration of 50% cellular cytotoxicity) to EC50. Results showed that aqueous extract of P. major possessed only a slight anti-herpes virus activity. In contrast, certain pure compounds belonging to the five different classes of chemicals found in extracts of this plant exhibited potent antiviral activity. Among them, caffeic acid exhibited the strongest activity against HSV-1 (EC50=15.3 microg/ml, SI=671), HSV-2 (EC50=87.3 microg/ml, SI=118) and ADV-3 (EC50=14.2 microg/ml, SI=727), whereas chlorogenic acid possessed the strongest anti-ADV-11 (EC50=13.3 microg/ml, SI=301) activity. The present study concludes that pure compounds of P. major, which possess antiviral activities are mainly derived from the phenolic compounds, especially caffeic acid. Its mode of action against HSV-2 and ADV-3 was found to be at multiplication stages (postinfection of HSV-1: 0-12 h; ADV-3: 0-2 h), and with SI values greater than 400, suggesting the potential use of this compound for treatment of the infection by these two viruses.

  9. Phenolic Compounds from the Flowers of Bombax malabaricum and Their Antioxidant and Antiviral Activities

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    Yu-Bo Zhang

    2015-11-01

    Full Text Available Three new phenolic compounds 1–3 and twenty known ones 4–23 were isolated from the flowers of Bombax malabaricum. Their chemical structures were elucidated by spectroscopic analyses (IR, ESI-MS, HR-ESI-MS, 1D- and 2D-NMR and chemical reactions. The antioxidant capacities of the isolated compounds were tested using FRAP and DPPH radical-scavenging assays, and compounds 4, 6, 8, 12, as well as the new compound 2, exhibited stronger antioxidant activities than ascorbic acid. Furthermore, all of compounds were tested for their antiviral activities against RSV by the CPE reduction assay and plaque reduction assay. Compounds 4, 10, 12 possess in vitro antiviral activities, and compound 10 exhibits potent anti-RSV effects, comparable to the positive control ribavirin.

  10. Activation of the Antiviral Kinase PKR and Viral Countermeasures

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    Bianca Dauber

    2009-10-01

    Full Text Available The interferon-induced double-stranded (dsRNA-dependent protein kinase (PKR limits viral replication by an eIF2α-mediated block of translation. Although many negative-strand RNA viruses activate PKR, the responsible RNAs have long remained elusive, as dsRNA, the canonical activator of PKR, has not been detected in cells infected with such viruses. In this review we focus on the activating RNA molecules of different virus families, in particular the negative-strand RNA viruses. We discuss the recently identified non-canonical activators 5’-triphosphate RNA and the vRNP of influenza virus and give an update on strategies of selected RNA and DNA viruses to prevent activation of PKR.

  11. Antiviral activity of carbohydrate-binding agents against Nidovirales in cell culture.

    Science.gov (United States)

    van der Meer, F J U M; de Haan, C A M; Schuurman, N M P; Haijema, B J; Peumans, W J; Van Damme, E J M; Delputte, P L; Balzarini, J; Egberink, H F

    2007-10-01

    Coronaviruses are important human and animal pathogens, the relevance of which increased due to the emergence of new human coronaviruses like SARS-CoV, HKU1 and NL63. Together with toroviruses, arteriviruses, and roniviruses the coronaviruses belong to the order Nidovirales. So far antivirals are hardly available to combat infections with viruses of this order. Therefore, various antiviral strategies to counter nidoviral infections are under evaluation. Lectins, which bind to N-linked oligosaccharide elements of enveloped viruses, can be considered as a conceptionally new class of virus inhibitors. These agents were recently evaluated for their antiviral activity towards a variety of enveloped viruses and were shown in most cases to inhibit virus infection at low concentrations. However, limited knowledge is available for their efficacy towards nidoviruses. In this article the application of the plant lectins Hippeastrum hybrid agglutinin (HHA), Galanthus nivalis agglutinin (GNA), Cymbidium sp. agglutinin (CA) and Urtica dioica agglutinin (UDA) as well as non-plant derived pradimicin-A (PRM-A) and cyanovirin-N (CV-N) as potential antiviral agents was evaluated. Three antiviral tests were compared based on different evaluation principles: cell viability (MTT-based colorimetric assay), number of infected cells (immunoperoxidase assay) and amount of viral protein expression (luciferase-based assay). The presence of carbohydrate-binding agents strongly inhibited coronaviruses (transmissible gastroenteritis virus, infectious bronchitis virus, feline coronaviruses serotypes I and II, mouse hepatitis virus), arteriviruses (equine arteritis virus and porcine respiratory and reproductive syndrome virus) and torovirus (equine Berne virus). Remarkably, serotype II feline coronaviruses and arteriviruses were not inhibited by PRM-A, in contrast to the other viruses tested.

  12. Antitumor and Antiviral Activity of Colombian Medicinal Plant Extracts

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    Betancur-Galvis LA

    1999-01-01

    Full Text Available Extracts of nine species of plants traditionally used in Colombia for the treatment of a variety of diseases were tested in vitro for their potential antitumor (cytotoxicity and antiherpetic activity. MTT (Tetrazolium blue and Neutral Red colorimetric assays were used to evaluate the reduction of viability of cell cultures in presence and absence of the extracts. MTT was also used to evaluate the effects of the extracts on the lytic activity of herpes simplex virus type 2 (HSV-2. The 50% cytotoxic concentration (CC50 and the 50% inhibitory concentration of the viral effect (EC50 for each extract were calculated by linear regression analysis. Extracts from Annona muricata, A. cherimolia and Rollinia membranacea, known for their cytotoxicity were used as positive controls. Likewise, acyclovir and heparin were used as positive controls of antiherpetic activity. Methanolic extract from Annona sp. on HEp-2 cells presented a CC50 value at 72 hr of 49.6x103mg/ml. Neither of the other extracts examined showed a significant cytotoxicity. The aqueous extract from Beta vulgaris, the ethanol extract from Callisia grasilis and the methanol extract Annona sp. showed some antiherpetic activity with acceptable therapeutic indexes (the ratio of CC50 to EC50. These species are good candidates for further activity-monitored fractionation to identify active principles.

  13. Antiviral Activity of Hatay Propolis Against Replication of Herpes Simplex Virus Type 1 and Type 2.

    Science.gov (United States)

    Yildirim, Ayse; Duran, Gulay Gulbol; Duran, Nizami; Jenedi, Kemal; Bolgul, Behiye Sezgin; Miraloglu, Meral; Muz, Mustafa

    2016-02-09

    BACKGROUND Propolis is a bee product widely used in folk medicine and possessing many pharmacological properties. In this study we aimed to investigate: i) the antiviral activities of Hatay propolis samples against HSV-1 and HSV-2 in HEp-2 cell line, and ii) the presence of the synergistic effects of propolis with acyclovir against these viruses. MATERIAL AND METHODS All experiments were carried out in HEp-2 cell cultures. Proliferation assays were performed in 24-well flat bottom microplates. We inoculated 1x105 cells per ml and RPMI 1640 medium with 10% fetal calf serum into each well. Studies to determine cytotoxic effect were performed. To investigate the presence of antiviral activity of propolis samples, different concentrations of propolis (3200, 1600, 800, 400, 200, 100, 75, 50, and 25 μg/mL) were added into the culture medium. The amplifications of HSV-1 and HSV-2 DNA were performed by real-time PCR method. Acyclovir (Sigma, USA) was chosen as a positive control. Cell morphology was evaluated by scanning electron microscopy (SEM). RESULTS The replication of HSV-1 and HSV-2 was significantly suppressed in the presence of 25, 50, and 100 μg/mL of Hatay propolis. We found that propolis began to inhibit HSV-1 replication after 24 h of incubation and propolis activity against HSV-2 was found to start at 48 h following incubation. The activity of propolis against both HSV-1 and HSV-2 was confirmed by a significant decrease in the number of viral copies. CONCLUSIONS We determined that Hatay propolis samples have important antiviral effects compared with acyclovir. In particular, the synergy produced by antiviral activity of propolis and acyclovir combined had a stronger effect against HSV-1 and HSV-2 than acyclovir alone.

  14. Antiviral activity of a Bacillus sp: P34 peptide against pathogenic viruses of domestic animals

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    Débora Scopel e Silva

    2014-09-01

    Full Text Available P34 is an antimicrobial peptide produced by a Bacillus sp. strain isolated from the intestinal contents of a fish in the Brazilian Amazon basin with reported antibacterial activity. The aim of this work was to evaluate the peptide P34 for its in vitro antiviral properties against canine adenovirus type 2 (CAV-2, canine coronavirus (CCoV, canine distemper virus (CDV, canine parvovirus type 2 (CPV-2, equine arteritis virus (EAV, equine influenza virus (EIV, feline calicivirus (FCV and feline herpesvirus type 1 (FHV-1. The results showed that the peptide P34 exhibited antiviral activity against EAV and FHV-1. The peptide P34 inhibited the replication of EAV by 99.9% and FHV-1 by 94.4%. Virucidal activity was detected only against EAV. When P34 and EAV were incubated for 6 h at 37 °C the viral titer reduced from 10(4.5 TCID50 to 10(2.75 TCID50, showing a percent of inhibition of 98.6%. In conclusion, our results demonstrated that P34 inhibited EAV and FHV-1 replication in infected cell cultures and it showed virucidal activity against EAV. Since there is documented resistance to the current drugs used against herpesviruses and there is no treatment for equine viral arteritis, it is advisable to search for new antiviral compounds to overcome these infections.

  15. Antiviral activity of a Bacillus sp. P34 peptide against pathogenic viruses of domestic animals

    Science.gov (United States)

    Silva, Débora Scopel e; de Castro, Clarissa Caetano; Silva, Fábio da Silva e; Sant’anna, Voltaire; Vargas, Gilberto D’Avila; de Lima, Marcelo; Fischer, Geferson; Brandelli, Adriano; da Motta, Amanda de Souza; Hübner, Silvia de Oliveira

    2014-01-01

    P34 is an antimicrobial peptide produced by a Bacillus sp. strain isolated from the intestinal contents of a fish in the Brazilian Amazon basin with reported antibacterial activity. The aim of this work was to evaluate the peptide P34 for its in vitro antiviral properties against canine adenovirus type 2 (CAV-2), canine coronavirus (CCoV), canine distemper virus (CDV), canine parvovirus type 2 (CPV-2), equine arteritis virus (EAV), equine influenza virus (EIV), feline calicivirus (FCV) and feline herpesvirus type 1 (FHV-1). The results showed that the peptide P34 exhibited antiviral activity against EAV and FHV-1. The peptide P34 inhibited the replication of EAV by 99.9% and FHV-1 by 94.4%. Virucidal activity was detected only against EAV. When P34 and EAV were incubated for 6 h at 37 °C the viral titer reduced from 104.5 TCID50 to 102.75 TCID50, showing a percent of inhibition of 98.6%. In conclusion, our results demonstrated that P34 inhibited EAV and FHV-1 replication in infected cell cultures and it showed virucidal activity against EAV. Since there is documented resistance to the current drugs used against herpesviruses and there is no treatment for equine viral arteritis, it is advisable to search for new antiviral compounds to overcome these infections. PMID:25477947

  16. Antiprotozoan and Antiviral Activities of Non-Cytotoxic Truncated and Variant Analogues of Mussel Defensin

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    Philippe Roch

    2004-01-01

    Full Text Available We previously reported the crucial role displayed by loop 3 of defensin isolated from the Mediterranean mussel, Mytilus galloprovincialis, in antibacterial and antifungal activities. We now investigated antiprotozoan and antiviral activities of some previously reported fragments B, D, E, P and Q. Two fragments (D and P efficiently killed Trypanosoma brucei (ID50 4–12 μM and Leishmania major (ID50 12–45 μM in a time/dose-dependent manner. Killing of T. brucei started as early as 1 h after initiation of contact with fragment D and reached 55% mortality after 6 h. Killing was temperature dependent and a temperature of 4°C efficiently impaired the ability to kill T. brucei. Fragments bound to the entire external epithelium of T. brucei. Prevention of HIV-1 infestation was obtained only with fragments P and Q at 20 μM. Even if fragment P was active on both targets, the specificity of fragments D and Q suggest that antiprotozoan and antiviral activities are mediated by different mechanisms. Truncated sequences of mussel defensin, including amino acid replacement to maintain 3D structure and increased positive net charge, also possess antiprotozoan and antiviral capabilities. New alternative and/or complementary antibiotics can be derived from the vast reservoir of natural antimicrobial peptides (AMPs contained in marine invertebrates.

  17. A Review on Antibacterial, Antiviral, and Antifungal Activity of Curcumin

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    Soheil Zorofchian Moghadamtousi

    2014-01-01

    Full Text Available Curcuma longa L. (Zingiberaceae family and its polyphenolic compound curcumin have been subjected to a variety of antimicrobial investigations due to extensive traditional uses and low side effects. Antimicrobial activities for curcumin and rhizome extract of C. longa against different bacteria, viruses, fungi, and parasites have been reported. The promising results for antimicrobial activity of curcumin made it a good candidate to enhance the inhibitory effect of existing antimicrobial agents through synergism. Indeed, different investigations have been done to increase the antimicrobial activity of curcumin, including synthesis of different chemical derivatives to increase its water solubility as well ass cell up take of curcumin. This review aims to summarize previous antimicrobial studies of curcumin towards its application in the future studies as a natural antimicrobial agent.

  18. Actinobacillus pleuropneumoniae possesses an antiviral activity against porcine reproductive and respiratory syndrome virus.

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    Cynthia Lévesque

    Full Text Available Pigs are often colonized by more than one bacterial and/or viral species during respiratory tract infections. This phenomenon is known as the porcine respiratory disease complex (PRDC. Actinobacillus pleuropneumoniae (App and porcine reproductive and respiratory syndrome virus (PRRSV are pathogens that are frequently involved in PRDC. The main objective of this project was to study the in vitro interactions between these two pathogens and the host cells in the context of mixed infections. To fulfill this objective, PRRSV permissive cell lines such as MARC-145, SJPL, and porcine alveolar macrophages (PAM were used. A pre-infection with PRRSV was performed at 0.5 multiplicity of infection (MOI followed by an infection with App at 10 MOI. Bacterial adherence and cell death were compared. Results showed that PRRSV pre-infection did not affect bacterial adherence to the cells. PRRSV and App co-infection produced an additive cytotoxicity effect. Interestingly, a pre-infection of SJPL and PAM cells with App blocked completely PRRSV infection. Incubation of SJPL and PAM cells with an App cell-free culture supernatant is also sufficient to significantly block PRRSV infection. This antiviral activity is not due to LPS but rather by small molecular weight, heat-resistant App metabolites (<1 kDa. The antiviral activity was also observed in SJPL cells infected with swine influenza virus but to a much lower extent compared to PRRSV. More importantly, the PRRSV antiviral activity of App was also seen with PAM, the cells targeted by the virus in vivo during infection in pigs. The antiviral activity might be due, at least in part, to the production of interferon γ. The use of in vitro experimental models to study viral and bacterial co-infections will lead to a better understanding of the interactions between pathogens and their host cells, and could allow the development of novel prophylactic and therapeutic tools.

  19. Anticancer molecule AS1411 exhibits low nanomolar antiviral activity against HIV-1.

    Science.gov (United States)

    Métifiot, Mathieu; Amrane, Samir; Mergny, Jean-Louis; Andreola, Marie-Line

    2015-11-01

    During clinical trials, a number of fully characterized molecules are dropped along the way because they do not provide enough benefit for the patient. Some of them show limited side effects and might be of great use for other applications. AS1411 is a nucleolin-targeting aptamer that underwent phase II clinical trials as anticancer agent. Here, we show that AS1411 exhibits extremely potent antiviral activity and is therefore an attractive new lead as anti-HIV agent.

  20. Antiviral Activity of Hatay Propolis Against Replication of Herpes Simplex Virus Type 1 and Type 2

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    Yildirim, Ayse; Duran, Gulay Gulbol; DURAN, Nizami; Jenedi, Kemal; Bolgul, Behiye Sezgin; Miraloglu, Meral; MUZ, Mustafa

    2016-01-01

    Background Propolis is a bee product widely used in folk medicine and possessing many pharmacological properties. In this study we aimed to investigate: i) the antiviral activities of Hatay propolis samples against HSV-1 and HSV-2 in HEp-2 cell line, and ii) the presence of the synergistic effects of propolis with acyclovir against these viruses. Material/Methods All experiments were carried out in HEp-2 cell cultures. Proliferation assays were performed in 24-well flat bottom microplates. We...

  1. Lipophilicity is a key factor to increase the antiviral activity of HIV neutralizing antibodies.

    Science.gov (United States)

    Augusto, Marcelo T; Hollmann, Axel; Troise, Fulvia; Veiga, Ana S; Pessi, Antonello; Santos, Nuno C

    2017-04-01

    The HIV broadly neutralizing antibody 2F5 targets the transiently exposed epitope in the membrane proximal external region (MPER) of HIV-1 gp41, by a two-step mechanism involving the viral membrane and this viral glycoprotein. It was recently shown that 2F5 conjugation with a cholesterol moiety outside of the antibody paratope substantially increases its antiviral activity. Additionally, the antiviral activity of D5, a human antibody that binds to the N-terminal heptad repeat (NHR) of gp41 and lacks membrane binding, was boosted by the same cholesterol conjugation. In this work, we evaluated the membrane affinity of both antibodies towards membranes of different compositions, using surface plasmon resonance. A correlation was found between membrane affinity and antiviral activity against HIV-1. We propose that the conjugation of cholesterol to 2F5 or D5 allows a higher degree of antibody pre-concentration at the viral membrane. This way, the antibodies become more available to bind efficiently to the gp41 epitope, blocking viral fusion faster than the unconjugated antibody. These results set up a relevant strategy to improve the rational design of therapeutic antibodies against HIV.

  2. Antiviral and Antioxidant Activities of Sulfated Galactomannans from Plants of Caatinga Biome

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    Márcia Maria Mendes Marques

    2015-01-01

    Full Text Available Dengue represents a serious social and economic public health problem; then trying to contribute to improve its control, the objective of this research was to develop phytoterapics for dengue treatment using natural resources from Caatinga biome. Galactomannans isolated from Adenanthera pavonina L., Caesalpinia ferrea Mart., and Dimorphandra gardneriana Tull were chemically sulfated in order to evaluate the antioxidant, and antiviral activities and the role in the inhibition of virus DENV-2 in Vero cells. A positive correlation between the degree of sulfation, antioxidant and antiviral activities was observed. The sulfated galactomannans showed binding to the virus surface, indicating that they interact with DENV-2. The sulfated galactomannans from C. ferrea showed 96% inhibition of replication of DENV-2 followed by D. gardneriana (94% and A. pavonina (77% at 25 µg/mL and all sulfated galactomannans also showed antioxidant activity. This work is the first report of the antioxidant and antiviral effects of sulfated galactomannans against DENV-2. The results are very promising and suggest that these sulfated galactomannans from plants of Caatinga biome act in the early step of viral infection. Thus, sulfated galactomannans may act as an entry inhibitor of DENV-2.

  3. Mechanism of TRIM25 Catalytic Activation in the Antiviral RIG-I Pathway

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    Jacint G. Sanchez

    2016-08-01

    Full Text Available Antiviral response pathways induce interferon by higher-order assembly of signaling complexes called signalosomes. Assembly of the RIG-I signalosome is regulated by K63-linked polyubiquitin chains, which are synthesized by the E3 ubiquitin ligase, TRIM25. We have previously shown that the TRIM25 coiled-coil domain is a stable, antiparallel dimer that positions two catalytic RING domains on opposite ends of an elongated rod. We now show that the RING domain is a separate self-association motif that engages ubiquitin-conjugated E2 enzymes as a dimer. RING dimerization is required for catalysis, TRIM25-mediated RIG-I ubiquitination, interferon induction, and antiviral activity. We also provide evidence that RING dimerization and E3 ligase activity are promoted by binding of the TRIM25 SPRY domain to the RIG-I effector domain. These results indicate that TRIM25 actively participates in higher-order assembly of the RIG-I signalosome and helps to fine-tune the efficiency of the RIG-I-mediated antiviral response.

  4. Antiviral and Antioxidant Activities of Sulfated Galactomannans from Plants of Caatinga Biome.

    Science.gov (United States)

    Marques, Márcia Maria Mendes; de Morais, Selene Maia; da Silva, Ana Raquel Araújo; Barroso, Naiara Dutra; Pontes Filho, Tadeu Rocha; Araújo, Fernanda Montenegro de Carvalho; Vieira, Ícaro Gusmão Pinto; Lima, Danielle Malta; Guedes, Maria Izabel Florindo

    2015-01-01

    Dengue represents a serious social and economic public health problem; then trying to contribute to improve its control, the objective of this research was to develop phytoterapics for dengue treatment using natural resources from Caatinga biome. Galactomannans isolated from Adenanthera pavonina L., Caesalpinia ferrea Mart., and Dimorphandra gardneriana Tull were chemically sulfated in order to evaluate the antioxidant, and antiviral activities and the role in the inhibition of virus DENV-2 in Vero cells. A positive correlation between the degree of sulfation, antioxidant and antiviral activities was observed. The sulfated galactomannans showed binding to the virus surface, indicating that they interact with DENV-2. The sulfated galactomannans from C. ferrea showed 96% inhibition of replication of DENV-2 followed by D. gardneriana (94%) and A. pavonina (77%) at 25 µg/mL and all sulfated galactomannans also showed antioxidant activity. This work is the first report of the antioxidant and antiviral effects of sulfated galactomannans against DENV-2. The results are very promising and suggest that these sulfated galactomannans from plants of Caatinga biome act in the early step of viral infection. Thus, sulfated galactomannans may act as an entry inhibitor of DENV-2.

  5. Tyrosinase inhibitory components from Aloe vera and their antiviral activity.

    Science.gov (United States)

    Kim, Jang Hoon; Yoon, Ju-Yeon; Yang, Seo Young; Choi, Seung-Kook; Kwon, Sun Jung; Cho, In Sook; Jeong, Min Hee; Ho Kim, Young; Choi, Gug Seoun

    2017-12-01

    A new compound, 9-dihydroxyl-2'-O-(Z)-cinnamoyl-7-methoxy-aloesin (1), and eight known compounds (2-9) were isolated from Aloe vera. Their structures were elucidated using 1D/2D nuclear magnetic resonance and mass spectra. Compound 9 exhibited reversible competitive inhibitory activity against the enzyme tyrosinase, with an IC50 value of 9.8 ± 0.9 µM. A molecular simulation revealed that compound 9 interacts via hydrogen bonding with residues His244, Thr261, and Val283 of tyrosinase. Additionally, compounds 3 and 7 were shown by half-leaf assays to exhibit inhibitory activity towards Pepper mild mottle virus.

  6. SUMO-interacting motifs of human TRIM5α are important for antiviral activity.

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    Gloria Arriagada

    2011-04-01

    Full Text Available Human TRIM5α potently restricts particular strains of murine leukemia viruses (the so-called N-tropic strains but not others (the B- or NB-tropic strains during early stages of infection. We show that overexpression of SUMO-1 in human 293T cells, but not in mouse MDTF cells, profoundly blocks N-MLV infection. This block is dependent on the tropism of the incoming virus, as neither B-, NB-, nor the mutant R110E of N-MLV CA (a B-tropic switch are affected by SUMO-1 overexpression. The block occurred prior to reverse transcription and could be abrogated by large amounts of restricted virus. Knockdown of TRIM5α in 293T SUMO-1-overexpressing cells resulted in ablation of the SUMO-1 antiviral effects, and this loss of restriction could be restored by expression of a human TRIM5α shRNA-resistant plasmid. Amino acid sequence analysis of human TRIM5α revealed a consensus SUMO conjugation site at the N-terminus and three putative SUMO interacting motifs (SIMs in the B30.2 domain. Mutations of the TRIM5α consensus SUMO conjugation site did not affect the antiviral activity of TRIM5α in any of the cell types tested. Mutation of the SIM consensus sequences, however, abolished TRIM5α antiviral activity against N-MLV. Mutation of lysines at a potential site of SUMOylation in the CA region of the Gag gene reduced the SUMO-1 block and the TRIM5α restriction of N-MLV. Our data suggest a novel aspect of TRIM5α-mediated restriction, in which the presence of intact SIMs in TRIM5α, and also the SUMO conjugation of CA, are required for restriction. We propose that at least a portion of the antiviral activity of TRIM5α is mediated through the binding of its SIMs to SUMO-conjugated CA.

  7. RNase and DNase activities of antiviral proteins from leaves of Bougainvillea xbuttiana.

    Science.gov (United States)

    Bhatia, Shikha; Lodha, M L

    2005-06-01

    Antiviral proteins (AVPs) purified from the leaves of Bougainvillea xbuttiana cv Mahara exhibited RNase activity against viral RNA of the tobamoviruses, Tobacco mosaic virus (TMV) and Sunnhemp rosette virus (SRV). They caused complete degradation of viral RNAs in a concentration-dependent manner. RNase activity gel assay ruled out the possibility of the presence of contaminating nucleases. AVPs also showed DNase activity, as indicated by conversion of supercoiled form of plasmid DNA into relaxed and linear forms. The implications of these activities in controlling plant viruses are discussed.

  8. The lipid moiety of brincidofovir is required for in vitro antiviral activity against Ebola virus.

    Science.gov (United States)

    McMullan, Laura K; Flint, Mike; Dyall, Julie; Albariño, César; Olinger, Gene G; Foster, Scott; Sethna, Phiroze; Hensley, Lisa E; Nichol, Stuart T; Lanier, E Randall; Spiropoulou, Christina F

    2016-01-01

    Brincidofovir (BCV) is the 3-hexadecyloxy-1-propanol (HDP) lipid conjugate of the acyclic nucleoside phosphonate cidofovir (CDV). BCV has established broad-spectrum activity against double-stranded DNA (dsDNA) viruses; however, its activity against RNA viruses has been less thoroughly evaluated. Here, we report that BCV inhibited infection of Ebola virus in multiple human cell lines. Unlike the mechanism of action for BCV against cytomegalovirus and other dsDNA viruses, phosphorylation of CDV to the diphosphate form appeared unnecessary. Instead, antiviral activity required the lipid moiety and in vitro activity against EBOV was observed for several HDP-nucleotide conjugates.

  9. Antiviral Activity of Obtained Extracts from Different Parts of Cupressus sempervirens against Herpes Simplex Virus Type 1

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    Mehrangiz Khajeh Karamadini

    2009-09-01

    Full Text Available Objective(sThe aim of this study was to search for new antiviral agents from herbal medicines. Ethanol extracts of C. semipervirens, C. semipervirens var. horizontalis and C. semipervirens cv. Cereiformis were used in experiments to test their influence on herpes viruses (HSV-1. Materials and MethodsHeLa cells monolayers were infected with herpes viruses (HSV-1. Antiviral activity of the plant extracts assessed using Hematoxylin & Eosin method and observed under a light microscope. All tests were compared with a positive control, acyclovir.ResultsResults showed that all three plants have antiviral activity against HSV-1 virus. The most active extract was the obtained extract from C. semipervirens. Among the different parts of this medicinal plant tested, the fruit’s extract appeared to possess the strongest anti- HSV activity.ConclusionIn conclusion, of the extracts tested in this survey all showed significant antiviral potency.

  10. Identification of alternatively translated Tetherin isoforms with differing antiviral and signaling activities.

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    Luis J Cocka

    2012-09-01

    Full Text Available Tetherin (BST-2/CD317/HM1.24 is an IFN induced transmembrane protein that restricts release of a broad range of enveloped viruses. Important features required for Tetherin activity and regulation reside within the cytoplasmic domain. Here we demonstrate that two isoforms, derived by alternative translation initiation from highly conserved methionine residues in the cytoplasmic domain, are produced in both cultured human cell lines and primary cells. These two isoforms have distinct biological properties. The short isoform (s-Tetherin, which lacks 12 residues present in the long isoform (l-Tetherin, is significantly more resistant to HIV-1 Vpu-mediated downregulation and consequently more effectively restricts HIV-1 viral budding in the presence of Vpu. s-Tetherin Vpu resistance can be accounted for by the loss of serine-threonine and tyrosine motifs present in the long isoform. By contrast, the l-Tetherin isoform was found to be an activator of nuclear factor-kappa B (NF-κB signaling whereas s-Tetherin does not activate NF-κB. Activation of NF-κB requires a tyrosine-based motif found within the cytoplasmic tail of the longer species and may entail formation of l-Tetherin homodimers since co-expression of s-Tetherin impairs the ability of the longer isoform to activate NF-κB. These results demonstrate a novel mechanism for control of Tetherin antiviral and signaling function and provide insight into Tetherin function both in the presence and absence of infection.

  11. Synergistic antiviral activity of ribavirin and interferon-α against parrot bornaviruses in avian cells.

    Science.gov (United States)

    Reuter, Antje; Horie, Masayuki; Höper, Dirk; Ohnemus, Annette; Narr, Andreas; Rinder, Monika; Beer, Martin; Staeheli, Peter; Rubbenstroth, Dennis

    2016-09-01

    Avian bornaviruses are the causative agents of proventricular dilatation disease (PDD), a widely distributed and often fatal disease in captive psittacines. Because neither specific prevention measures nor therapies against PDD and bornavirus infections are currently available, new antiviral strategies are required to improve animal health. We show here that the nucleoside analogue ribavirin inhibited bornavirus activity in a polymerase reconstitution assay and reduced viral load in avian cell lines infected with two different parrot bornaviruses. Furthermore, we observed that ribavirin enhanced type I IFN signalling in avian cells. Combined treatment of avian bornavirus-infected cells with ribavirin and recombinant IFN-α strongly enhanced the antiviral efficiency compared to either drug alone. The combined use of ribavirin and type I IFN might represent a promising new strategy for therapeutic treatment of captive parrots persistently infected with avian bornaviruses.

  12. Interferon lambda 4 signals via the IFNλ receptor to regulate antiviral activity against HCV and coronaviruses

    DEFF Research Database (Denmark)

    Hamming, Ole Jensen; Terczynska-Dyla, Ewa; Vieyres, Gabrielle;

    2013-01-01

    The IFNL4 gene is a recently discovered type III interferon, which in a significant fraction of the human population harbours a frameshift mutation abolishing the IFNλ4 ORF. The expression of IFNλ4 is correlated with both poor spontaneous clearance of hepatitis C virus (HCV) and poor response...... to treatment with type I interferon. Here, we show that the IFNL4 gene encodes an active type III interferon, named IFNλ4, which signals through the IFNλR1 and IL-10R2 receptor chains. Recombinant IFNλ4 is antiviral against both HCV and coronaviruses at levels comparable to IFNλ3. However, the secretion....... Together, these findings result in the paradox that IFNλ4 is strongly antiviral but a disadvantage during HCV infection...

  13. Antiviral activities of extracts and phenolic components of two Spondias species against dengue virus

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    Ara Silva

    2011-01-01

    Full Text Available In recent years, the search for natural plant products to fight viral diseases has been increasing. In this work, two Spondias species, namely S. mombin and S. tuberosa, found in Ceará state (Brazil, and their main phenolic components were evaluated against dengue virus. In vitro antiviral tests were performed against type-2 dengue virus by the MTT method and standard cytopathic effect reduction assay in C6/36 cells. Cytotoxicity was also evaluated by MTT. The presence of phenolic compounds quercetin, rutin, and ellagic acid in plant extracts was characterized by HPLC analysis. Both Spondias species extracts and components were nontoxic to the cells whereas rutin and quercetin displayed relevant antiviral activity with IC50 of 362.68 µg/mL and 500 µg/mL, respectively.

  14. Antiviral activity of mycosynthesized silver nanoparticles against herpes simplex virus and human parainfluenza virus type 3

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    Gaikwad S

    2013-11-01

    Full Text Available Swapnil Gaikwad,1 Avinash Ingle,1 Aniket Gade,1 Mahendra Rai,1 Annarita Falanga,3 Novella Incoronato,2 Luigi Russo,2 Stefania Galdiero,3 Massimilano Galdiero2 1Department of Biotechnology, Sant Gadge Baba Amravati University, Amravati, Maharashtra, India; 2Department of Experimental Medicine, Division of Microbiology, II University of Naples, 3Department of Pharmacy, University of Naples “Federico II”, DFM and Institute of Biostructures and Bioimages, Naples, Italy Abstract: The interaction between silver nanoparticles and viruses is attracting great interest due to the potential antiviral activity of these particles, and is the subject of much research effort in the treatment of infectious diseases. In this work, we demonstrate that silver nanoparticles undergo a size-dependent interaction with herpes simplex virus types 1 and 2 and with human parainfluenza virus type 3. We show that production of silver nanoparticles from different fungi is feasible, and their antiviral activity is dependent on the production system used. Silver nanoparticles are capable of reducing viral infectivity, probably by blocking interaction of the virus with the cell, which might depend on the size and zeta potential of the silver nanoparticles. Smaller-sized nanoparticles were able to inhibit the infectivity of the viruses analyzed. Keywords: silver nanoparticles, antiviral, herpes simplex virus, parainfluenza virus

  15. The antiviral activity of arctigenin in traditional Chinese medicine on porcine circovirus type 2.

    Science.gov (United States)

    Chen, Jie; Li, Wentao; Jin, Erguang; He, Qigai; Yan, Weidong; Yang, Hanchun; Gong, Shiyu; Guo, Yi; Fu, Shulin; Chen, Xiabing; Ye, Shengqiang; Qian, Yunguo

    2016-06-01

    Arctigenin (ACT) is a phenylpropanoid dibenzylbutyrolactone lignan extracted from the traditional herb Arctium lappa L. (Compositae) with anti-viral and anti-inflammatory effects. Here, we investigated the antiviral activity of ACT found in traditional Chinese medicine on porcine circovirus type 2 (PCV2) in vitro and in vivo. Results showed that dosing of 15.6-62.5μg/mL ACT could significantly inhibit the PCV2 proliferation in PK-15 cells (P<0.01). Dosing of 62.5μg/mL ACT 0, 4 or 8h after challenge inoculation significantly inhibited the proliferation of 1MOI and 10MOI in PK-15 cells (P<0.01), and the inhibitory effect of ACT dosing 4h or 8h post-inoculation was greater than 0h after dosing (P<0.01). In vivo test with mice challenge against PCV2 infection demonstrated that intraperitoneal injection of 200μg/kg ACT significantly inhibited PCV2 proliferation in the lungs, spleens and inguinal lymph nodes, with an effect similar to ribavirin, demonstrating the effectiveness of ACT as an antiviral agent against PCV2 in vitro and in vivo. This compound, therefore, may have the potential to serve as a drug for protection of pigs against the infection of PCV2.

  16. In vitro antiviral activity of Ficus carica latex against caprine herpesvirus-1.

    Science.gov (United States)

    Camero, Michele; Marinaro, Mariarosaria; Lovero, Angela; Elia, Gabriella; Losurdo, Michele; Buonavoglia, Canio; Tempesta, Maria

    2014-01-01

    The latex of Ficus carica Linn. (Moraceae) has been shown to possess antiviral properties against some human viruses. To determine the ability of F. carica latex (F-latex) to interfere with the infection of caprine herpesvirus-1 (CpHV-1) in vitro, F-latex was resuspended in culture media containing 1% ethanol and was tested for potential antiviral effects against CpHV-1. Titration of CpHV-1 in the presence or in the absence of F-latex was performed on monolayers of Madin Darby Bovine Kidney (MDBK) cells. Simultaneous addition of F-latex and CpHV-1 to monolayers of MDBK cells resulted in a significant reduction of CpHV-1 titres 3 days post-infection and this effect was comparable to that induced by acyclovir. The study suggests that the F-latex is able to interfere with the replication of CpHV-1 in vitro on MDBK cells and future studies will determine the mechanisms responsible for the observed antiviral activity.

  17. The anti-obesity drug orlistat reveals anti-viral activity.

    Science.gov (United States)

    Ammer, Elisabeth; Nietzsche, Sandor; Rien, Christian; Kühnl, Alexander; Mader, Theresa; Heller, Regine; Sauerbrei, Andreas; Henke, Andreas

    2015-12-01

    The administration of drugs to inhibit metabolic pathways not only reduces the risk of obesity-induced diseases in humans but may also hamper the replication of different viral pathogens. In order to investigate the value of the US Food and Drug Administration-approved anti-obesity drug orlistat in view of its anti-viral activity against different human-pathogenic viruses, several anti-viral studies, electron microscopy analyses as well as fatty acid uptake experiments were performed. The results indicate that administrations of non-cytotoxic concentrations of orlistat reduced the replication of coxsackievirus B3 (CVB3) in different cell types significantly. Moreover, orlistat revealed cell protective effects and modified the formation of multi-layered structures in CVB3-infected cells, which are necessary for viral replication. Lowering fatty acid uptake from the extracellular environment by phloretin administrations had only marginal impact on CVB3 replication. Finally, orlistat reduced also the replication of varicella-zoster virus moderately but had no significant influence on the replication of influenza A viruses. The data support further experiments into the value of orlistat as an inhibitor of the fatty acid synthase to develop new anti-viral compounds, which are based on the modulation of cellular metabolic pathways.

  18. Battle between influenza A virus and a newly identified antiviral activity of the PARP-containing ZAPL protein

    Science.gov (United States)

    Liu, Chien-Hung; Zhou, Ligang; Chen, Guifang; Krug, Robert M.

    2015-01-01

    Previous studies showed that ZAPL (PARP-13.1) exerts its antiviral activity via its N-terminal zinc fingers that bind the mRNAs of some viruses, leading to mRNA degradation. Here we identify a different antiviral activity of ZAPL that is directed against influenza A virus. This ZAPL antiviral activity involves its C-terminal PARP domain, which binds the viral PB2 and PA polymerase proteins, leading to their proteasomal degradation. After the PB2 and PA proteins are poly(ADP-ribosylated), they are associated with the region of ZAPL that includes both the PARP domain and the adjacent WWE domain that is known to bind poly(ADP-ribose) chains. These ZAPL-associated PB2 and PA proteins are then ubiquitinated, followed by proteasomal degradation. This antiviral activity is counteracted by the viral PB1 polymerase protein, which binds close to the PARP domain and causes PB2 and PA to dissociate from ZAPL and escape degradation, explaining why ZAPL only moderately inhibits influenza A virus replication. Hence influenza A virus has partially won the battle against this newly identified ZAPL antiviral activity. Eliminating PB1 binding to ZAPL would be expected to substantially increase the inhibition of influenza A virus replication, so that the PB1 interface with ZAPL is a potential target for antiviral development. PMID:26504237

  19. Proteolytic activation of the SARS-coronavirus spike protein: cutting enzymes at the cutting edge of antiviral research.

    Science.gov (United States)

    Simmons, Graham; Zmora, Pawel; Gierer, Stefanie; Heurich, Adeline; Pöhlmann, Stefan

    2013-12-01

    The severe acute respiratory syndrome (SARS) pandemic revealed that zoonotic transmission of animal coronaviruses (CoV) to humans poses a significant threat to public health and warrants surveillance and the development of countermeasures. The activity of host cell proteases, which cleave and activate the SARS-CoV spike (S) protein, is essential for viral infectivity and constitutes a target for intervention. However, the identities of the proteases involved have been unclear. Pioneer studies identified cathepsins and type II transmembrane serine proteases as cellular activators of SARS-CoV and demonstrated that several emerging viruses might exploit these enzymes to promote their spread. Here, we will review the proteolytic systems hijacked by SARS-CoV for S protein activation, we will discuss their contribution to viral spread in the host and we will outline antiviral strategies targeting these enzymes. This paper forms part of a series of invited articles in Antiviral Research on "From SARS to MERS: 10years of research on highly pathogenic human coronaviruses.'' Copyright © 2013 Elsevier B.V. All rights reserved.

  20. Antiviral activity of Paulownia tomentosa against enterovirus 71 of hand, foot, and mouth disease.

    Science.gov (United States)

    Ji, Ping; Chen, Changmai; Hu, Yanan; Zhan, Zixuan; Pan, Wei; Li, Rongrong; Li, Erguang; Ge, Hui-Ming; Yang, Guang

    2015-01-01

    The bark, leaves, and flowers of Paulownia trees have been used in traditional Chinese medicine to treat infectious and inflammatory diseases. We investigated the antiviral effects of Paulownia tomentosa flowers, an herbal medicine used in some provinces of P. R. China for the treatment of skin rashes and blisters. Dried flowers of P. tomentosa were extracted with methanol and tested for antiviral activity against enterovirus 71 (EV71) and coxsackievirus A16 (CAV16), the predominant etiologic agents of hand, foot, and mouth disease in P. R. China. The extract inhibited EV71 infection, although no effect was detected against CAV16 infection. Bioactivity-guided fractionation was performed to identify apigenin as an active component of the flowers. The EC50 value for apigenin to block EV71 infection was 11.0 µM, with a selectivity index of approximately 9.3. Although it is a common dietary flavonoid, only apigenin, and not similar compounds like naringenin and quercetin, were active against EV71 infection. As an RNA virus, the genome of EV71 has an internal ribosome entry site that interacts with heterogeneous nuclear ribonucleoproteins (hnRNPs) and regulates viral translation. Cross-linking followed by immunoprecipitation and reverse transcription-polymerase chain reaction (RT-PCR) analysis showed that EV71 RNA was associated with hnRNPs A1 and A2. Apigenin treatment disrupted this association, indicating that apigenin suppressed EV71 replication through a novel mechanism by targeting the trans-acting factors. This study therefore validates the effects of Paulownia against EV71 infection. It also yielded mechanistic insights on apigenin as an active compound for the antiviral activity of P. tomentosa against EV71 infection.

  1. A Study on in vitro antiviral activities of lyophilized extracts of Glycyrrhiza glabra on Hepatitis B Virus

    Directory of Open Access Journals (Sweden)

    Sangeetha Vani

    2016-06-01

    Full Text Available The present study is to determine the effect of lyophilized extracts of different solvents of Glycyrrhiza glabra on Hepatitis B. The lyophilized plant extracts were collected and studied for its cytotoxicity in HepG2 cell line and in vitro antiviral activity of these extracts was investigated by HBs Ag binding Inhibition Assay, Hepatitis B Virus DNA Polymerase Inhibition Assay using fluorescent probes. The results from Glycyrrhiza glabra were promising in acting as a potent antiviral agent.

  2. SYNTHESIS AND ANTIVIRAL ACTIVITY OF NEW THIAZOLE, 1,2,4-TRIAZOL AND OXINDOLE DERIVATIVES

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    Oleg Radul

    2011-06-01

    Full Text Available The synthesis and antiviral activity evaluation of new derivatives of 2-aminothiazole, 1,2,4-triazole, as well as oxindoles has been realized. The synthesized compounds exhibited different cytotoxicity, in particular, oxindols 4 , 5 , 7 , 8 , 9, 10, 11, 12, 13, 58 as well as thiazole/triazole 73 and 75 turned out to be the most cytotoxic for MT-4 cell lines. The compounds 11, 12, 73, and 75 are more toxic than reference compound Efavirenz. As far as the antiviral activity is concerned, none of the title compounds turned out active against Reo-1, Sb-1, VSV, RSV, YFV and VV viruses. The results obtained against Bovine Viral Diarrhoea Virus (BVDV showed that nine compounds (six from oxindol’s seria 6, 12, 13, 52, 56, 58 and three 73, 75, 77 of triazole homologues resulted moderate active. Among all of them, the most potent compound was 52, with EC50 of 6.6 μM. Studies of effect of synthesized compounds against Coxsakie Virus (CVB-2 revealed that only two compounds, 13 and 73 exhibit moderate activity (EC50 >40 and >18 μM, respectively. It should be noticed that eleven compounds, 4, 5, 7, 8, 9, 10, 11, 12, 13, 58, and 75 showed moderate activity against HIV-1 (EC50 >16 – m >59μM.

  3. Immunomodulating and antiviral activities of Uncaria tomentosa on human monocytes infected with Dengue Virus-2.

    Science.gov (United States)

    Reis, Sonia Regina I N; Valente, Ligia M M; Sampaio, André L; Siani, Antonio C; Gandini, Mariana; Azeredo, Elzinandes L; D'Avila, Luiz A; Mazzei, José L; Henriques, Maria das Graças M; Kubelka, Claire F

    2008-03-01

    Uncaria tomentosa (Willd.) DC., a large woody vine native to the Amazon and Central American rainforests has been used medicinally by indigenous peoples since ancient times and has scientifically proven immunomodulating, anti-inflammatory, cytotoxic and antioxidant activities. Several inflammatory mediators that are implicated in vascular permeability and shock are produced after Dengue Virus (DENV) infection by monocytes, the primary targets for virus replication. Here we assessed the immunoregulatory and antiviral activities from U. tomentosa-derived samples, which were tested in an in vitro DENV infection model. DENV-2 infected human monocytes were incubated with U. tomentosa hydro-alcoholic extract or either its pentacyclic oxindole alkaloid-enriched or non-alkaloid fractions. The antiviral activity was determined by viral antigen (DENV-Ag) detection in monocytes by flow cytometry. Our results demonstrated an in vitro inhibitory activity by both extract and alkaloidal fraction, reducing DENV-Ag+ cell rates in treated monocytes. A multiple microbead immunoassay was applied for cytokine determination (TNF-alpha, IFN-alpha, IL-6 and IL-10) in infected monocyte culture supernatants. The alkaloidal fraction induced a strong immunomodulation: TNF-alpha and IFN-alpha levels were significantly decreased and there was a tendency towards IL-10 modulation. We conclude that the alkaloidal fraction was the most effective in reducing monocyte infection rates and cytokine levels. The antiviral and immunomodulating in vitro effects from U. tomentosa pentacyclic oxindole alkaloids displayed novel properties regarding therapeutic procedures in Dengue Fever and might be further investigated as a promising candidate for clinical application.

  4. Rhodiola rosea exerts anti-viral activity in athletes following a competitive marathon race

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    Maryam eAhmed

    2015-07-01

    Full Text Available Rhodiola rosea, a medicinal plant with demonstrated adaptogenic properties, has recently been reported to contain active compounds with antimicrobial activity. The goal of this study was to measure the antiviral and antibacterial properties of the bioactive metabolites of Rhodiola rosea in the serum of experienced marathon runners following supplementation. Marathon runners, randomly divided into two group, ingested 600mg/day of Rhodiola rosea (n=24, 6 female, 18 male or placebo (n=24, 7 female, 17 male for 30 days prior to, the day of, and seven days post-marathon. Blood serum samples were collected the day before, 15 minutes post- and 1.5 hours post-marathon. Serum from Rhodiola rosea supplemented runners collected after marathon running did not attenuate the marathon-induced susceptibility of HeLa cells to killing by vesicular stomatitis virus (VSV. However, the use of Rhodiola rosea induced antiviral activity at early times post-infection by delaying an exercise-dependent increase in virus replication (P=0.013 compared to placebo. Serum from both groups collected 15 minutes post-marathon significantly promoted the growth of Escherichia coli in culture as compared to serum collected the day before the marathon (P=0.003, all subjects. Furthermore, the serum from subjects ingesting Rhodiola rosea did not display antibacterial properties at any time point as indicated by a lack of group differences immediately (P=0.785 or 1.5 hours (P=0.633 post-marathon. These results indicate that bioactive compounds in the serum of subjects ingesting Rhodiola rosea may exert protective effects against virus replication following intense and prolonged exercise by inducing antiviral activity.

  5. Antiviral activity of four types of bioflavonoid against dengue virus type-2

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    Zandi Keivan

    2011-12-01

    Full Text Available Abstract Background Dengue is a major mosquito-borne disease currently with no effective antiviral or vaccine available. Effort to find antivirals for it has focused on bioflavonoids, a plant-derived polyphenolic compounds with many potential health benefits. In the present study, antiviral activity of four types of bioflavonoid against dengue virus type -2 (DENV-2 in Vero cell was evaluated. Anti-dengue activity of these compounds was determined at different stages of DENV-2 infection and replication cycle. DENV replication was measured by Foci Forming Unit Reduction Assay (FFURA and quantitative RT-PCR. Selectivity Index value (SI was determined as the ratio of cytotoxic concentration 50 (CC50 to inhibitory concentration 50 (IC50 for each compound. Results The half maximal inhibitory concentration (IC50 of quercetin against dengue virus was 35.7 μg mL-1 when it was used after virus adsorption to the cells. The IC50 decreased to 28.9 μg mL-1 when the cells were treated continuously for 5 h before virus infection and up to 4 days post-infection. The SI values for quercetin were 7.07 and 8.74 μg mL-1, respectively, the highest compared to all bioflavonoids studied. Naringin only exhibited anti-adsorption effects against DENV-2 with IC50 = 168.2 μg mL-1 and its related SI was 1.3. Daidzein showed a weak anti-dengue activity with IC50 = 142.6 μg mL-1 when the DENV-2 infected cells were treated after virus adsorption. The SI value for this compound was 1.03. Hesperetin did not exhibit any antiviral activity against DENV-2. The findings obtained from Foci Forming Unit Reduction Assay (FFURA were corroborated by findings of the qRT-PCR assays. Quercetin and daidzein (50 μg mL-1 reduced DENV-2 RNA levels by 67% and 25%, respectively. There was no significant inhibition of DENV-2 RNA levels with naringin and hesperetin. Conclusion Results from the study suggest that only quercetin demonstrated significant anti-DENV-2 inhibitory activities. Other

  6. Resveratrol exhibits a strong cytotoxic activity in cultured cells and has an antiviral action against polyomavirus: potential clinical use

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    Galati Gaspare

    2009-07-01

    Full Text Available Abstract Background Resveratrol is a non flavonoid polyphenol compound present in many plants and fruits and, at especially high concentrations, in the grape berries of Vitis vinifera. This compound has a strong bioactivity and its cytoprotective action has been demonstrated, however at high concentrations the drug exhibits also an effective anti-proliferative action. We recently showed its ability to abolish the effects of oxidative stress in cultured cells. In this work we assayed the bioactivity of resveratrol as antiproliferative and antiviral drug in cultured fibroblasts. Studies by other Authors showed that this natural compound inhibits the proliferation of different viruses such as herpes simplex, varicella-zoster and influenza A. The results presented here show an evident toxic activity of the drug at high concentrations, on the other hand at sub-cytotoxic concentrations, resveratrol can effectively inhibit the synthesis of polyomavirus DNA. A possible interpretation is that, due to the damage caused by resveratrol to the plasma membrane, the transfer of the virus from the endoplasmic reticulum to the nucleus, may be hindered thus inhibiting the production of viral DNA. Methods The mouse fibroblast line 3T6 and the human tumor line HL60 were used throughout the work. Cell viability and vital cell count were assessed respectively, by the MTT assay and Trypan Blue staining. Cytotoxic properties and evaluation of viral DNA production by agarose gel electrophoresis were performed according to standard protocols. Results Our results show a clear dose dependent both cytotoxic and antiviral effect of resveratrol respectively at high and low concentrations. The cytotoxic action is exerted towards a stabilized cell-line (3T6 as well as a tumor-line (HL60. Furthermore the antiviral action is evident after the phase of virion entry, therefore data suggest that the drug acts during the synthesis of the viral progeny DNA. Conclusion Resveratrol is

  7. Fucoidans from the brown seaweed Adenocystis utricularis: extraction methods, antiviral activity and structural studies.

    Science.gov (United States)

    Ponce, Nora M A; Pujol, Carlos A; Damonte, Elsa B; Flores, María L; Stortz, Carlos A

    2003-01-20

    The brown seaweed Adenocystis utricularis (family Adenocystaceae, order Ectocarpales sensu lato) was extracted in parallel with three solvents usually utilized for obtaining fucoidans: distilled water, 2% calcium chloride solution and diluted hydrochloric acid (pH 2) solution. In each case, the extraction was effected at room temperature and then at 70 degrees C. The extraction yields and characteristics of the products were similar in the three cases, with only minor differences. The analytical features of the products indicate that two different types of fucoidans are present in this seaweed. One of them, mostly extracted at room temperature, is composed mainly of L-fucose, D-galactose and ester sulfate (the 'galactofucan'). The other product (the 'uronofucoidan') is the major component of the extracts obtained at 70 degrees C. It is composed mainly of fucose, accompanied by other monosaccharides (mostly Man, but also Glc, Xyl, Rha and Gal), significant amounts of uronic acids and low proportions of sulfate ester. Fractionation with the cationic detergent cetrimide has allowed achieving a better separation of the galactofucan and uronofucoidan components. The galactofucans show a high inhibitory activity against herpes simplex virus 1 and 2, with no cytotoxicity, whereas the uronofucoidans carry no antiviral activity. Structural studies on the galactofucan fractions were carried out by methylation analysis, desulfation and NMR spectroscopy. The fucan constituent is mainly composed of 3-linked alpha-L-fucopyranosyl backbone, mostly sulfated at C-4, and branched at C-2 with non-sulfated fucofuranosyl and fucopyranosyl units, and 2-sulfated fucopyranosyl units. The galactan moiety is more heterogeneous, with predominant D-galactopyranose units linked on C-3 and C-6, and sulfation mostly on C-4, even in terminal non-reducing units. It may be inferred that at least some of these galactose units carry the alpha-configuration.

  8. Phytochemical screening and antiviral activity of some medicinal plants from the island Soqotra.

    Science.gov (United States)

    Mothana, Ramzi A A; Mentel, Renate; Reiss, Christiane; Lindequist, Ulrike

    2006-04-01

    Methanol and hot-aqueous extracts of 25 different plant species, used in Yemeni traditional medicine and growing, partly as endemic plants, on the island Soqotra have been investigated for their antiviral activity. In addition, the phytochemical identification of the main chemical constituents was performed. The extracts were assayed in two in vitro viral systems, which used influenza virus type A/MDCK cells and herpes simplex virus type 1/Vero cells, at non-cytotoxic concentrations. The herpes simplex virus type 1 showed more sensitivity than the influenza virus type A against the extracts investigated. The methanol extracts of Boswellia ameero, Boswellia elongata, Buxus hildebrandtii, Cissus hamaderohensis, Cleome socotrana, Dracaena cinnabari, Exacum affine, Jatropha unicostata and Kalanchoe farinacea showed anti-influenza virus type A activity with 50% inhibition (IC50) concentrations ranging from 0.7 to 12.5 microg/mL. In addition, 17 plants of the 25 investigated exhibited anti-HSV-1 activity. The antiviral activity of some active extracts was also observed on a molecular level.

  9. Functional Diversity of Anti-Lipopolysaccharide Factor Isoforms in Shrimp and Their Characters Related to Antiviral Activity

    Directory of Open Access Journals (Sweden)

    Shihao Li

    2015-04-01

    Full Text Available Anti-lipopolysaccharide factor (ALF is a small protein with broad-spectrum antimicrobial activity, which has potential application in the disease control. Previously, we isolated seven ALF isoforms from the Chinese shrimp Fenneropenaeus chinensis. In the present study, their distributions in tissues of shrimp were analyzed and the data showed that different isoforms had different expression profiles, which suggested that they might have different functions. Then, the functions of different isoforms were studied by analyzing the antibacterial and antiviral activities of the functional domain of ALFs, the LPS-binding domain (LBD, which were synthesized by chemical methods. Different ALFs showed distinct antibacterial and antiviral activities, which were consistent with their diverse tissue distribution patterns. Sequence analysis on the LBD domain of different isoforms revealed that an identical lysine residue site was specifically conserved in peptides with anti-WSSV activity. In order to confirm whether this lysine residue is critical to the antiviral activity of the peptide, new peptides were synthesized by changing residues at this site. Changing the lysine residue at the specific site to other amino acid residue, the antiviral activity of the peptide apparently decreased. While replacing other residue with a lysine residue at this site in LBD peptide without anti-WSSV activity, the peptide will obtain the antiviral activity to WSSV. These results not only showed us a comprehensive understanding on the function of ALFs from F. chinensis, but also provided clues for the development of ALFs as potential therapeutic drugs to WSSV.

  10. Functional diversity of anti-lipopolysaccharide factor isoforms in shrimp and their characters related to antiviral activity.

    Science.gov (United States)

    Li, Shihao; Guo, Shuyue; Li, Fuhua; Xiang, Jianhai

    2015-04-27

    Anti-lipopolysaccharide factor (ALF) is a small protein with broad-spectrum antimicrobial activity, which has potential application in the disease control. Previously, we isolated seven ALF isoforms from the Chinese shrimp Fenneropenaeus chinensis. In the present study, their distributions in tissues of shrimp were analyzed and the data showed that different isoforms had different expression profiles, which suggested that they might have different functions. Then, the functions of different isoforms were studied by analyzing the antibacterial and antiviral activities of the functional domain of ALFs, the LPS-binding domain (LBD), which were synthesized by chemical methods. Different ALFs showed distinct antibacterial and antiviral activities, which were consistent with their diverse tissue distribution patterns. Sequence analysis on the LBD domain of different isoforms revealed that an identical lysine residue site was specifically conserved in peptides with anti-WSSV activity. In order to confirm whether this lysine residue is critical to the antiviral activity of the peptide, new peptides were synthesized by changing residues at this site. Changing the lysine residue at the specific site to other amino acid residue, the antiviral activity of the peptide apparently decreased. While replacing other residue with a lysine residue at this site in LBD peptide without anti-WSSV activity, the peptide will obtain the antiviral activity to WSSV. These results not only showed us a comprehensive understanding on the function of ALFs from F. chinensis, but also provided clues for the development of ALFs as potential therapeutic drugs to WSSV.

  11. Guanylate-Binding Protein 1, an Interferon-Induced GTPase, Exerts an Antiviral Activity against Classical Swine Fever Virus Depending on Its GTPase Activity

    Science.gov (United States)

    Li, Lian-Feng; Yu, Jiahui; Li, Yongfeng; Wang, Jinghan; Li, Su; Zhang, Lingkai; Xia, Shui-Li; Yang, Qian; Wang, Xiao; Yu, Shaoxiong; Luo, Yuzi; Sun, Yuan; Zhu, Yan; Munir, Muhammad

    2016-01-01

    ABSTRACT Many viruses trigger the type I interferon (IFN) pathway upon infection, resulting in the transcription of hundreds of interferon-stimulated genes (ISGs), which define the antiviral state of the host. Classical swine fever virus (CSFV) is the causative agent of classical swine fever (CSF), a highly contagious viral disease endangering the pig industry in many countries. However, anti-CSFV ISGs are poorly documented. Here we screened 20 ISGs that are commonly induced by type I IFNs against CSFV in lentivirus-delivered cell lines, resulting in the identification of guanylate-binding protein 1 (GBP1) as a potent anti-CSFV ISG. We observed that overexpression of GBP1, an IFN-induced GTPase, remarkably suppressed CSFV replication, whereas knockdown of endogenous GBP1 expression by small interfering RNAs significantly promoted CSFV growth. Furthermore, we demonstrated that GBP1 acted mainly on the early phase of CSFV replication and inhibited the translation efficiency of the internal ribosome entry site of CSFV. In addition, we found that GBP1 was upregulated at the transcriptional level in CSFV-infected PK-15 cells and in various organs of CSFV-infected pigs. Coimmunoprecipitation and glutathione S-transferase (GST) pulldown assays revealed that GBP1 interacted with the NS5A protein of CSFV, and this interaction was mapped in the N-terminal globular GTPase domain of GBP1. Interestingly, the K51 of GBP1, which is crucial for its GTPase activity, was essential for the inhibition of CSFV replication. We showed further that the NS5A-GBP1 interaction inhibited GTPase activity, which was critical for its antiviral effect. Taking our findings together, GBP1 is an anti-CSFV ISG whose action depends on its GTPase activity. IMPORTANCE Classical swine fever virus (CSFV) is the causative agent of classical swine fever (CSF), an economically important viral disease affecting the pig industry in many countries. To date, only a few host restriction factors against CSFV

  12. Interferon lambda 4 signals via the IFNλ receptor to regulate antiviral activity against HCV and coronaviruses

    DEFF Research Database (Denmark)

    Hamming, Ole Jensen; Terczynska-Dyla, Ewa; Vieyres, Gabrielle

    2013-01-01

    The IFNL4 gene is a recently discovered type III interferon, which in a significant fraction of the human population harbours a frameshift mutation abolishing the IFNλ4 ORF. The expression of IFNλ4 is correlated with both poor spontaneous clearance of hepatitis C virus (HCV) and poor response...... to treatment with type I interferon. Here, we show that the IFNL4 gene encodes an active type III interferon, named IFNλ4, which signals through the IFNλR1 and IL-10R2 receptor chains. Recombinant IFNλ4 is antiviral against both HCV and coronaviruses at levels comparable to IFNλ3. However, the secretion...

  13. Indole alkaloid sulfonic acids from an aqueous extract of Isatis indigotica roots and their antiviral activity

    Directory of Open Access Journals (Sweden)

    Lingjie Meng

    2017-05-01

    Full Text Available Six new indole alkaloid sulfonic acids (1–6, together with two analogues (7 and 8 that were previously reported as synthetic products, were isolated from an aqueous extract of the Isatis indigotica root. Their structures including the absolute configurations were determined by spectroscopic data analysis, combined with enzyme hydrolysis and comparison of experimental circular dichroism and calculated electronic circular dichroism spectra. In the preliminary assay, compounds 2 and 4 showed antiviral activity against Coxsackie virus B3 and influenza virus A/Hanfang/359/95 (H3N2, respectively.

  14. NMR structure of mussel mytilin, and antiviral-antibacterial activities of derived synthetic peptides

    OpenAIRE

    Roch, Philippe; Yang, Y.; Toubiana, Mylene; Aumelas, A

    2008-01-01

    Mytilin is a 34-residue antibacterial peptide from the mussel Mytilus galloprovincialis, which in addition possesses in vitro antiviral activity. The three-dimensional solution structure of the synthetic mytilin was established by using 1H NMR and consists of the common cysteine-stabilized alpha beta motif close to the one observed in the mussel defensin MGD-1. Mytilin is characterized by 8 cysteines engaged in four disulfide bonds (2-27, 6-29, 10-31, and 15-34) only involving the beta-strand...

  15. [Antiviral activity in vitro and pharmacokinetics of HCV entry inhibitor AVR560].

    Science.gov (United States)

    Ivashchenko, A V; Iamanushkin, P M; Mit'kin, O D; Ezhova, E V; Korzinov, O M; Bulanova, E A; Koriakova, A G; Vyshemirskaia, P V; Bychko, V V; Ivashchenko, A A

    2014-01-01

    Several novel compounds were found to be potent inhibitors of the HCV (JFH-1 isolate) infection in vitro. Human serum did not significantly reduce antiviral activity of the lead compound, AVR560 (New Guinea type 2) in in vitro infection experiments. AVR560 also did not inhibit any of the tested human CYP450 isozymes (3A4, 1A2, 2C19 and 2D6). In the pharmacokinetic studies in mice, rats and dogs, favorable pharmacokinetic profiles and good oral bioavailability were observed for AV560. Further pre-clinical studies with this novel HCV inhibitor are in progress.

  16. Autophagy is involved in anti-viral activity of pentagalloylglucose (PGG) against Herpes simplex virus type 1 infection in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Pei, Ying, E-mail: peiying-19802@163.com [Biomedicine Research and Development Center of Jinan University, Guangzhou, Guangdong 510632 (China); Chen, Zhen-Ping, E-mail: 530670663@qq.com [Biomedicine Research and Development Center of Jinan University, Guangzhou, Guangdong 510632 (China); Ju, Huai-Qiang, E-mail: 344464448@qq.com [Biomedicine Research and Development Center of Jinan University, Guangzhou, Guangdong 510632 (China); Komatsu, Masaaki, E-mail: komatsu-ms@igakuken.or.jp [Laboratory of Frontier Science, Tokyo Metropolitan Institute of Medical Science, Bunkyo-ku, Tokyo 113-8613 (Japan); Ji, Yu-hua, E-mail: tjyh@jnu.edu.cn [Institute of Tissue Transplantation and Immunology, College of Life Science and Technology, Jinan University, Guangzhou 510632 (China); Liu, Ge, E-mail: lggege_15@hotmail.com [Division of Molecular Pharmacology of Infectious agents, Department of Molecular Microbiology and Immunology, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki 852-8521 (Japan); Guo, Chao-wan, E-mail: chaovan_kwok@hotmail.com [Division of Molecular Pharmacology of Infectious agents, Department of Molecular Microbiology and Immunology, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki 852-8521 (Japan); Zhang, Ying-Jun, E-mail: zhangyj@mail.kib.ac.cn [Kunming Institute of Botany, the Chinese Academy of Sciences, Yunnan, Kunming 650204 (China); Yang, Chong-Ren, E-mail: cryang@mail.kib.ac.cn [Kunming Institute of Botany, the Chinese Academy of Sciences, Yunnan, Kunming 650204 (China); Wang, Yi-Fei, E-mail: twang-yf@163.com [Biomedicine Research and Development Center of Jinan University, Guangzhou, Guangdong 510632 (China); Kitazato, Kaio, E-mail: kkholi@msn.com [Division of Molecular Pharmacology of Infectious agents, Department of Molecular Microbiology and Immunology, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki 852-8521 (Japan)

    2011-02-11

    Research highlights: {yields} We showed PGG has anti-viral activity against Herpes simplex virus type 1 (HSV-1) and can induce autophgy. {yields} Autophagy may be a novel and important mechanism mediating PGG anti-viral activities. {yields} Inhibition of mTOR pathway is an important mechanism of induction of autophagy by PGG. -- Abstract: Pentagalloylglucose (PGG) is a natural polyphenolic compound with broad-spectrum anti-viral activity, however, the mechanisms underlying anti-viral activity remain undefined. In this study, we investigated the effects of PGG on anti-viral activity against Herpes simplex virus type 1 (HSV-1) associated with autophagy. We found that the PGG anti-HSV-1 activity was impaired significantly in MEF-atg7{sup -/-} cells (autophagy-defective cells) derived from an atg7{sup -/-} knockout mouse. Transmission electron microscopy revealed that PGG-induced autophagosomes engulfed HSV-1 virions. The mTOR signaling pathway, an essential pathway for the regulation of autophagy, was found to be suppressed following PGG treatment. Data presented in this report demonstrated for the first time that autophagy induced following PGG treatment contributed to its anti-HSV activity in vitro.

  17. Effect of Egyptian propolis on the susceptibility of LDL to oxidative modification and its antiviral activity with special emphasis on chemical composition.

    Science.gov (United States)

    Abd El-Hady, Faten K; Hegazi, Ahmed G; Wollenweber, Eckhard

    2007-01-01

    The antioxidant activity of eight Egyptian propolis samples from different localities was evaluated by the antioxidative potential and capacity of the DPPH-ESR signal, superoxide anion generated in the xanthine-xanthine oxidase (XOD) system and low density lipoprotein (LDL) peroxidation assay. As, F, Is and D samples showed the highest antioxidative capacity and potential, respectively. The El, IsR, Is, D and So samples exhibited highly significant antioxidant activity in the XOD system and in LDL peroxidation assays. The antiviral activity of propolis samples was investigated. They showed variations in their activity; sample D induced the highest antiviral activity against Newcastle disease virus and infectious bursal disease virus. 42 Polyphenolic compounds were identified by HPLC; 13 aromatic acids, esters and alcohols were present, 29 flavonoids were identified, 6 of them being new to propolis.

  18. Evaluation of antiviral activity of fractionated extracts of sage Salvia officinalis L. (Lamiaceae

    Directory of Open Access Journals (Sweden)

    Šmidling Dragana

    2008-01-01

    Full Text Available In the present study, we examined cytotoxicity and extracellular and intracellular antiviral activity of frac­tionated extracts of wild and cultivated sage Salvia officinalis L. (Lamiaceae in vitro using the WISH-VSV model system. Extracts were obtained by fractionating depigmented ethanol extracts of sage plants with supercritical CO2 at different pressures. Cytotoxicity was determined by examining cellular morphology in situ with the aid of a colorimetric micromethod and by cell staining with trypan blue. The fraction of distilled cultivated sage obtained at CO2 pressure of 300 bars and temperature of 60°C (149/3 was the most cytotoxic, with CTD10 44 μg/ml. That of non-distilled cultivated sage obtained at CO2 pressure of 500 bars and temperature of 100°C (144/5 was the least toxic (CTD10 199 μg/ml. Moreover, 144/5 had an antiviral effect at the intracellular level: when added 5 hours before VSV infection, it caused 100% reduction of CPE at concentrations of 99.5 and 199.0 μg/ml; when added after virus penetration had occurred, the same concentrations caused 35 and 60% reduction, respectively. The obtained results indicate that antiviral activity of 144/5 involves inhibition of the early steps of the virus infective cycle without a direct virucidal effect. Abbreviations: WISH - human amnion epithelial cells, VSV - vesicular stomatitis virus, HSV - herpes simplex virus, CPE - cytopathic effect, IS - selectivity index, TCID50 - tissue culture infective dose, CTD10 - 10% cytotoxic concentrations.

  19. Structural characteristics and antiviral activity of multiple peptides derived from MDV glycoproteins B and H

    Directory of Open Access Journals (Sweden)

    Wang Ming

    2011-04-01

    Full Text Available Abstract Background Marek's disease virus (MDV, which is widely considered to be a natural model of virus-induced lymphoma, has the potential to cause tremendous losses in the poultry industry. To investigate the structural basis of MDV membrane fusion and to identify new viral targets for inhibition, we examined the domains of the MDV glycoproteins gH and gB. Results Four peptides derived from the MDV glycoprotein gH (gHH1, gHH2, gHH3, and gHH5 and one peptide derived from gB (gBH1 could efficiently inhibit plaque formation in primary chicken embryo fibroblast cells (CEFs with 50% inhibitory concentrations (IC50 of below 12 μM. These peptides were also significantly able to reduce lesion formation on chorioallantoic membranes (CAMs of infected chicken embryos at a concentration of 0.5 mM in 60 μl of solution. The HR2 peptide from Newcastle disease virus (NDVHR2 exerted effects on MDV specifically at the stage of virus entry (i.e., in a cell pre-treatment assay and an embryo co-treatment assay, suggesting cross-inhibitory effects of NDV HR2 on MDV infection. None of the peptides exhibited cytotoxic effects at the concentrations tested. Structural characteristics of the five peptides were examined further. Conclusions The five MDV-derived peptides demonstrated potent antiviral activity, not only in plaque formation assays in vitro, but also in lesion formation assays in vivo. The present study examining the antiviral activity of these MDV peptides, which are useful as small-molecule antiviral inhibitors, provides information about the MDV entry mechanism.

  20. Epigenetic reprogramming of the type III interferon response potentiates antiviral activity and suppresses tumor growth.

    Directory of Open Access Journals (Sweden)

    Siyuan Ding

    2014-01-01

    Full Text Available Type III interferon (IFN-λ exhibits potent antiviral activity similar to IFN-α/β, but in contrast to the ubiquitous expression of the IFN-α/β receptor, the IFN-λ receptor is restricted to cells of epithelial origin. Despite the importance of IFN-λ in tissue-specific antiviral immunity, the molecular mechanisms responsible for this confined receptor expression remain elusive. Here, we demonstrate that the histone deacetylase (HDAC repression machinery mediates transcriptional silencing of the unique IFN-λ receptor subunit (IFNLR1 in a cell-type-specific manner. Importantly, HDAC inhibitors elevate receptor expression and restore sensitivity to IFN-λ in previously nonresponsive cells, thereby enhancing protection against viral pathogens. In addition, blocking HDAC activity renders nonresponsive cell types susceptible to the pro-apoptotic activity of IFN-λ, revealing the combination of HDAC inhibitors and IFN-λ to be a potential antitumor strategy. These results demonstrate that the type III IFN response may be therapeutically harnessed by epigenetic rewiring of the IFN-λ receptor expression program.

  1. Activation of cGAS-dependent antiviral responses by DNA intercalating agents.

    Science.gov (United States)

    Pépin, Geneviève; Nejad, Charlotte; Thomas, Belinda J; Ferrand, Jonathan; McArthur, Kate; Bardin, Philip G; Williams, Bryan R G; Gantier, Michael P

    2017-01-09

    Acridine dyes, including proflavine and acriflavine, were commonly used as antiseptics before the advent of penicillins in the mid-1940s. While their mode of action on pathogens was originally attributed to their DNA intercalating activity, work in the early 1970s suggested involvement of the host immune responses, characterized by induction of interferon (IFN)-like activities through an unknown mechanism. We demonstrate here that sub-toxic concentrations of a mixture of acriflavine and proflavine instigate a cyclic-GMP-AMP (cGAMP) synthase (cGAS)-dependent type-I IFN antiviral response. This pertains to the capacity of these compounds to induce low level DNA damage and cytoplasmic DNA leakage, resulting in cGAS-dependent cGAMP-like activity. Critically, acriflavine:proflavine pre-treatment of human primary bronchial epithelial cells significantly reduced rhinovirus infection. Collectively, our findings constitute the first evidence that non-toxic DNA binding agents have the capacity to act as indirect agonists of cGAS, to exert potent antiviral effects in mammalian cells. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

  2. Antiviral Activity of Diterpene Esters on Chikungunya Virus and HIV Replication.

    Science.gov (United States)

    Nothias-Scaglia, Louis-Félix; Pannecouque, Christophe; Renucci, Franck; Delang, Leen; Neyts, Johan; Roussi, Fanny; Costa, Jean; Leyssen, Pieter; Litaudon, Marc; Paolini, Julien

    2015-06-26

    Recently, new daphnane, tigliane, and jatrophane diterpenoids have been isolated from various Euphorbiaceae species, of which some have been shown to be potent inhibitors of chikungunya virus (CHIKV) replication. To further explore this type of compound, the antiviral activity of a series of 29 commercially available natural diterpenoids was evaluated. Phorbol-12,13-didecanoate (11) proved to be the most potent inhibitor, with an EC50 value of 6.0 ± 0.9 nM and a selectivity index (SI) of 686, which is in line with the previously reported anti-CHIKV potency for the structurally related 12-O-tetradecanoylphorbol-13-acetate (13). Most of the other compounds exhibited low to moderate activity, including an ingenane-type diterpene ester, compound 28, with an EC50 value of 1.2 ± 0.1 μM and SI = 6.4. Diterpene compounds are known also to inhibit HIV replication, so the antiviral activities of compounds 1-29 were evaluated also against HIV-1 and HIV-2. Tigliane- (4β-hydroxyphorbol analogues 10, 11, 13, 15, 16, and 18) and ingenane-type (27 and 28) diterpene esters were shown to inhibit HIV replication in vitro at the nanomolar level. A Pearson analysis performed with the anti-CHIKV and anti-HIV data sets demonstrated a linear relationship, which supported the hypothesis made that PKC may be an important target in CHIKV replication.

  3. In Vitro Evaluation of Antiprotozoal and Antiviral Activities of Extracts from Argentinean Mikania Species

    Directory of Open Access Journals (Sweden)

    Laura C. Laurella

    2012-01-01

    Full Text Available The aim of this study was to investigate the antiprotozoal and antiviral activities of four Argentinean Mikania species. The organic and aqueous extracts of Mikania micrantha, M. parodii, M. periplocifolia, and M. cordifolia were tested on Trypanosoma cruzi epimastigotes, Leishmania braziliensis promastigotes, and dengue virus type 2. The organic extract of M. micrantha was the most active against T. cruzi and L. braziliensis exhibiting a growth inhibition of 77.6±4.5% and 84.9±6.1%, respectively, at a concentration of 10 μg/ml. The bioguided fractionation of M. micrantha organic extract led to the identification of two active fractions. The chromatographic profile and infrared analysis of these fractions revealed the presence of sesquiterpene lactones. None of the tested extracts were active against dengue virus type 2.

  4. Analysis and prediction of highly effective antiviral peptides based on random forests.

    Directory of Open Access Journals (Sweden)

    Kuan Y Chang

    Full Text Available The goal of this study was to examine and predict antiviral peptides. Although antiviral peptides hold great potential in antiviral drug discovery, little is done in antiviral peptide prediction. In this study, we demonstrate that a physicochemical model using random forests outperform in distinguishing antiviral peptides. On the experimental benchmark, our physicochemical model aided with aggregation and secondary structural features reaches 90% accuracy and 0.79 Matthew's correlation coefficient, which exceeds the previous models. The results suggest that aggregation could be an important feature for identifying antiviral peptides. In addition, our analysis reveals the characteristics of the antiviral peptides such as the importance of lysine and the abundance of α-helical secondary structures.

  5. Anti-tumor and anti-viral activities of Galanthus nivalis agglutinin (GNA)-related lectins.

    Science.gov (United States)

    Wu, Lei; Bao, Jin-Ku

    2013-04-01

    Galanthus nivalis agglutinin (GNA)-related lectin family, a superfamily of strictly mannose-binding specific lectins widespread among monocotyledonous plants, is well-known to possess a broad range of biological functions such as anti-tumor, anti-viral and anti-fungal activities. Herein, we mainly focused on exploring the precise molecular mechanisms by which GNA-related lectins induce cancer cell apoptotic and autophagic death targeting mitochondria-mediated ROS-p38-p53 apoptotic or autophagic pathway, Ras-Raf and PI3K-Akt anti-apoptotic or anti-autophagic pathways. In addition, we further discussed the molecular mechanisms of GNA-related lectins exerting anti-viral activities by blocking the entry of the virus into its target cells, preventing transmission of the virus as well as forcing virus to delete glycan in its envelope protein and triggering neutralizing antibody. In conclusion, these findings may provide a new perspective of GNA-related lectins as potential drugs for cancer and virus therapeutics in the future.

  6. Enhancement of the antiviral activity against caprine herpesvirus type 1 of Acyclovir in association with Mizoribine.

    Science.gov (United States)

    Camero, Michele; Buonavoglia, Domenico; Lucente, Maria Stella; Losurdo, Michele; Crescenzo, Giuseppe; Trerotoli, Paolo; Casalino, Elisabetta; Martella, Vito; Elia, Gabriella; Tempesta, Maria

    2017-04-01

    Caprine herpesvirus 1 (CpHV-1) infection in goats is responsible for genital lesions resembling the lesions induced by herpesvirus 2 in humans (HHV-2). The immunosuppressive drug Mizoribine (MIZ) is able to increase the antiviral activity of Acyclovir (ACV) against herpesvirus infections, raising interesting perspectives on new combined therapeutic strategies. In this study the anti-CpHV-1 activity in vitro of ACV alone or in combination with MIZ was evaluated. ACV (100μg/ml) displayed an antiviral effect on CpHV-1 replication. This inhibitory effect was higher when ACV (100μg/ml) was used in association with MIZ (20μg/ml). Other combinations of ACV and MIZ in various concentrations were not as effective as ACV 100μg/ml/MIZ 20μg/ml. These findings suggest that the association of ACV and MIZ is potentially useful for treatment of genital infection by herpesviruses. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Metabolic variations, antioxidant potential, and antiviral activity of different extracts of Eugenia singampattiana (an endangered medicinal plant used by Kani tribals, Tamil Nadu, India) leaf.

    Science.gov (United States)

    John, K M Maria; Ayyanar, Muniappan; Jeeva, Subbiah; Suresh, Murugesan; Enkhtaivan, Gansukh; Kim, Doo Hwan

    2014-01-01

    Eugenia singampattiana is an endangered medicinal plant used by the Kani tribals of South India. The plant had been studied for its antioxidant, antitumor, antihyperlipidemic, and antidiabetic activity. But its primary and secondary metabolites profile and its antiviral properties were unknown, and so this study sought to identify this aspect in Eugenia singampattiana plant through different extraction methods along with their activities against porcine reproductive and respiratory syndrome virus (PRRSV). The GC-MS analysis revealed that 11 primary metabolites showed significant variations among the extracts. Except for fructose all other metabolites were high with water extract. Among 12 secondary metabolites showing variations, the levels of 4-hydroxy benzoic acid, caffeic acid, rutin, ferulic acid, coumaric acid, epigallocatechin gallate, quercetin, myricetin, and kaempferol were high with methanol extract. Since the flavonoid content of methanol extracts was high, the antioxidant potential, such as ABTS, and phosphomolybdenum activity increased. The plants antiviral activity against PRRSV was for the first time confirmed and the results revealed that methanol 25 µg and 75 to 100 µg in case of water extracts revealed antiviral activity.

  8. Lead optimization of an acylhydrazone scaffold possessing antiviral activity against Lassa virus.

    Science.gov (United States)

    Burgeson, James R; Gharaibeh, Dima N; Moore, Amy L; Larson, Ryan A; Amberg, Sean M; Bolken, Tove' C; Hruby, Dennis E; Dai, Dongcheng

    2013-11-01

    Previously we reported the optimization of antiviral scaffolds containing benzimidazole and related heterocycles possessing activity against a variety of arenaviruses. These series of compounds were discovered through an HTS campaign of a 400,000 small molecule library using lentivirus-based pseudotypes incorporated with the Lassa virus envelope glycoprotein (LASV GP). This screening also uncovered an alternate series of very potent arenavirus inhibitors based upon an acylhydrazone scaffold. Subsequent SAR analysis of this chemical series involved various substitutions throughout the chemical framework along with assessment of the preferred stereochemistry. These studies led to an optimized analog (ST-161) possessing subnanomolar activity against LASV and submicromolar activity against a number of other viruses in the Arenaviridae family.

  9. Structure-Activity Relationships of Acyclic Selenopurine Nucleosides as Antiviral Agents

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    Pramod K. Sahu

    2017-07-01

    Full Text Available A series of acyclic selenopurine nucleosides 3a–f and 4a–g were synthesized based on the bioisosteric rationale between oxygen and selenium, and then evaluated for antiviral activity. Among the compounds tested, seleno-acyclovir (4a exhibited the most potent anti-herpes simplex virus (HSV-1 (EC50 = 1.47 µM and HSV-2 (EC50 = 6.34 µM activities without cytotoxicity up to 100 µM, while 2,6-diaminopurine derivatives 4e–g exhibited significant anti-human cytomegalovirus (HCMV activity, which is slightly more potent than the guanine derivative 4d, indicating that they might act as prodrugs of seleno-ganciclovir (4d.

  10. Role of phosphate groups on antiviral activity of casein phosphopeptide against feline calicivirus as a surrogate for norovirus.

    Science.gov (United States)

    Lebetwa, Ntshepisa; Mitani, Takakazu; Nakamura, Soichiro; Katayama, Shigeru

    2017-04-01

    Current research on the gastrointestinal digestion of milk-casein strongly suggests the existence of novel bioactive peptides with antiviral activities that are attributable to their immunostimulatory effects. In the present study, we investigated the antiviral activity of casein peptides rich in phosphate groups, such as casein phosphopeptide (CPP-III). We prepared two types of CPP with different phosphorylation levels to clarify the role of the phosphate group. Further phosphorylation of CPP-III was conducted by dry heating with sodium pyrophosphate, whereas dephosphorylation was performed enzymatically using alkaline phosphatase and alkaline treatment. Feline calicivirus (FCV) strain F9, a typical norovirus surrogate, and Crandell Rees feline kidney cells were used as the target virus and host cells, respectively. Antiviral activity was determined based on the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and quantitative polymerase chain reaction quantification of antiviral cytokine mRNA expression. Higher cell viability was observed in the host cells treated with phosphorylated CPP-III, and a significant up-regulation of type 1 interferon expression was induced compared to that treated with native CPP-III. However, dephosphorylation of CPP-III resulted in a decrease in the anti-FCV effect. The CPP effect was enhanced by the introduction of additional phosphates and conversely weakened by their elimination. Therefore, CPP-III phosphorylation represents an emerging approach for the production of food-grade antiviral agents. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  11. Synthesis and molecular modelling of unsaturated exomethylene pyranonucleoside analogues with antitumor and antiviral activities.

    Science.gov (United States)

    Agelis, George; Tzioumaki, Niki; Tselios, Theodore; Botić, Tanja; Cencic, Avrelija; Komiotis, Dimitri

    2008-07-01

    This report describes the total and facile synthesis of the unsaturated keto and exomethylene pyranonucleoside analogues, 1-(2,3,4-trideoxy-4-methylene-6-O-trityl-alpha-D-glycero-hex-2-enopyranosyl)uracil (10), 1-(2,3-dideoxy-alpha-D-glycero-hex-2-enopyranosyl-4-ulose)uracil (17) and 1-(2,3,4-trideoxy-4-methylene-alpha-D-glycero-hex-2-enopyranosyl)uracil (18). Commercially available 1,2,3,4,6-penta-O-acetyl-alpha-D-mannopyranose (1) was condensed with silylated uracil, deacetylated and acetalated to afford 1-(2,3-O-isopropylidene-alpha-D-mannopyranosyl)uracil (4). Two different synthetic routes were investigated for the conversion of 4 into the olefinic derivative 1-(2,3,4-trideoxy-4-methylene-6-O-trityl-alpha-D-glycero-hex-2-enopyranosyl)uracil (10). Although the two procedures are quite similar with respect to yields and final products, the second also leads to the keto-2',3'-unsaturated analogue (17). The new analogues were evaluated for their anticancer and antiviral activities using several tumor cell lines and gastrointestinal rotavirus. All of the compounds showed direct antiviral effect against rotavirus infectivity in Caco-2 cell line. Moreover, 1-(2,3,4-trideoxy-4-methylene-6-O-trityl-alpha-D-glycero-hex-2-enopyranosyl)uracil (10) was found to be potent in MCF-7 breast carcinoma cell line.

  12. Genetic polymorphisms and antiviral activity in the bovine MX1 gene.

    Science.gov (United States)

    Nakatsu, Y; Yamada, K; Ueda, J; Onogi, A; Ables, G P; Nishibori, M; Hata, H; Takada, A; Sawai, K; Tanabe, Y; Morita, M; Daikohara, M; Watanabe, T

    2004-06-01

    Bovine MX1 cDNAs consisting of 2280 bp from 11 animals of five breeds and from a cultured cell line were sequenced and compared with previously reported data. Ten nucleotide substitutions were synonymous mutations, and a single nucleotide substitution at 458 resulted in an amino acid exchange of Ile (ATT) and Met (ATG). A 13-bp deletion-insertion mutation was also found in the 3'-UTR. Based on the nucleotide substitutions found in this study, bovine MX1 cDNA was classified into 11 genotypes. A phylogenetic tree of the 11 genotypes suggested that the genotypes observed in Brahman were a great genetic distance from other genotypes. An 18-bp deletion-insertion variation at position 171 was found to be the result of alternative splicing. The 18-bp deletion-insertion is located at the boundary between exon 3 and intron 3. Permanently transfected 3T3 cell lines expressing bovine MX1 mRNA were established to analyse the antiviral potential against VSVDeltaG*-G infection. Transfected cell clones expressing bovine MX1 mRNA showed a significantly smaller number of cells infected with VSVDeltaG*-G compared with the control cells. These results indicate that the bovine MX1 protein has potent antiviral activity.

  13. Biological activities of the antiviral protein BE27 from sugar beet (Beta vulgaris L.).

    Science.gov (United States)

    Iglesias, Rosario; Citores, Lucía; Di Maro, Antimo; Ferreras, José M

    2015-02-01

    The ribosome inactivating protein BE27 displays several biological activities in vitro that could result in a broad action against several types of pathogens. Beetin 27 (BE27), a ribosome-inactivating protein (RIP) from sugar beet (Beta vulgaris L.) leaves, is an antiviral protein induced by virus and signaling compounds such as hydrogen peroxide and salicylic acid. Its role as a defense protein has been attributed to its RNA polynucleotide:adenosine glycosidase activity. Here we tested other putative activities of BE27 that could have a defensive role against pathogens finding that BE27 displays rRNA N-glycosidase activity against yeast and Agrobacterium tumefaciens ribosomes, DNA polynucleotide:adenosine glycosidase activity against herring sperm DNA, and magnesium-dependent endonuclease activity against the supercoiled plasmid PUC19 (nicking activity). The nicking activity could be a consequence of an unusual conformation of the BE27 active site, similar to that of PD-L1, a RIP from Phytolacca dioica L. leaves. Additionally, BE27 possesses superoxide dismutase activity, thus being able to produce the signal compound hydrogen peroxide. BE27 is also toxic to COLO 320 cells, inducing apoptosis in these cells by either activating the caspase pathways and/or inhibiting protein synthesis. The combined effect of these biological activities could result in a broad action against several types of pathogens such as virus, bacteria, fungi or insects.

  14. Ophthalmic antiviral chemotherapy : An overview

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    Athmanathan Sreedharan

    1997-01-01

    Full Text Available Antiviral drug development has been slow due to many factors. One such factor is the difficulty to block the viral replication in the cell without adversely affecting the host cell metabolic activity. Most of the antiviral compounds are analogs of purines and pyramidines. Currently available antiviral drugs mainly inhibit viral nucleic acid synthesis, hence act only on actively replicating viruses. This article presents an overview of some of the commonly used antiviral agents in clinical ophthalmology.

  15. In Vitro Antiviral Activity and Resistance Profile Characterization of the Hepatitis C Virus NS5A Inhibitor Ledipasvir

    Science.gov (United States)

    Tian, Yang; Doehle, Brian; Peng, Betty; Corsa, Amoreena; Lee, Yu-Jen; Gong, Ruoyu; Yu, Mei; Han, Bin; Xu, Simin; Dvory-Sobol, Hadas; Perron, Michel; Xu, Yili; Mo, Hongmei; Pagratis, Nikos; Link, John O.; Delaney, William

    2016-01-01

    Ledipasvir (LDV; GS-5885), a component of Harvoni (a fixed-dose combination of LDV with sofosbuvir [SOF]), is approved to treat chronic hepatitis C virus (HCV) infection. Here, we report key preclinical antiviral properties of LDV, including in vitro potency, in vitro resistance profile, and activity in combination with other anti-HCV agents. LDV has picomolar antiviral activity against genotype 1a and genotype 1b replicons with 50% effective concentration (EC50) values of 0.031 nM and 0.004 nM, respectively. LDV is also active against HCV genotypes 4a, 4d, 5a, and 6a with EC50 values of 0.11 to 1.1 nM. LDV has relatively less in vitro antiviral activity against genotypes 2a, 2b, 3a, and 6e, with EC50 values of 16 to 530 nM. In vitro resistance selection with LDV identified the single Y93H and Q30E resistance-associated variants (RAVs) in the NS5A gene; these RAVs were also observed in patients after a 3-day monotherapy treatment. In vitro antiviral combination studies indicate that LDV has additive to moderately synergistic antiviral activity when combined with other classes of HCV direct-acting antiviral (DAA) agents, including NS3/4A protease inhibitors and the nucleotide NS5B polymerase inhibitor SOF. Furthermore, LDV is active against known NS3 protease and NS5B polymerase inhibitor RAVs with EC50 values equivalent to those for the wild type. PMID:26824950

  16. Molecular evolution of the porcine type I interferon family: subtype-specific expression and antiviral activity.

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    Yongming Sang

    Full Text Available Type I interferons (IFNs, key antiviral cytokines, evolve to adapt with ever-changing viral threats during vertebrate speciation. Due to novel pathogenic pressure associated with Suidae speciation and domestication, porcine IFNs evolutionarily engender both molecular and functional diversification, which have not been well addressed in pigs, an important livestock species and animal model for biomedical sciences. Annotation of current swine genome assembly Sscrofa10.2 reveals 57 functional genes and 16 pseudogenes of type I IFNs. Subfamilies of multiple IFNA, IFNW and porcine-specific IFND genes are separated into four clusters with ∼ 60 kb intervals within the IFNB/IFNE bordered region in SSC1, and each cluster contains mingled subtypes of IFNA, IFNW and IFND. Further curation of the 57 functional IFN genes indicates that they include 18 potential artifactual duplicates. We performed phylogenetic construction as well as analyses of gene duplication/conversion and natural selection and showed that porcine type I IFN genes have been undergoing active diversification through both gene duplication and conversion. Extensive analyses of the non-coding sequences proximal to all IFN coding regions identified several genomic repetitive elements significantly associated with different IFN subtypes. Family-wide studies further revealed their molecular diversity with respect to differential expression and restrictive activity on the resurgence of a porcine endogenous retrovirus. Based on predicted 3-D structures of representative animal IFNs and inferred activity, we categorized the general functional propensity underlying the structure-activity relationship. Evidence indicates gene expansion of porcine type I IFNs. Genomic repetitive elements that associated with IFN subtypes may serve as molecular signatures of respective IFN subtypes and genomic mechanisms to mediate IFN gene evolution and expression. In summary, the porcine type I IFN profile has

  17. NMR structure of mussel mytilin, and antiviral-antibacterial activities of derived synthetic peptides.

    Science.gov (United States)

    Roch, Philippe; Yang, Yinshan; Toubiana, Mylène; Aumelas, André

    2008-01-01

    Mytilin is a 34-residue antibacterial peptide from the mussel Mytilus galloprovincialis, which in addition possesses in vitro antiviral activity. The three-dimensional solution structure of the synthetic mytilin was established by using 1H NMR and consists of the common cysteine-stabilized alphabeta motif close to the one observed in the mussel defensin MGD-1. Mytilin is characterized by 8 cysteines engaged in four disulfide bonds (2-27, 6-29, 10-31, and 15-34) only involving the beta-strand II. Hydrophilic and hydrophobic areas of mytilin account for 63% and 37%, respectively, a ratio very close to that of MGD-1 (64% and 36%). One linear and three cyclic fragments were designed from the interstrand loop sequence known to retain the biological activities in MGD-1. Only the fragment of 10 amino acids (C10C) constrained by two disulfide bonds in a stable beta-hairpin structure was able to inhibit the mortality of Palaemon serratus shrimp injected with white spot syndrome virus (WSSV). Fifty percent inhibition was obtained by in vitro pre-incubation of WSSV with 45 microM of C10C compared with 7 microM for mytilin. Interaction between the fragment and the virus occurred very rapidly as 40% survival was recorded after only 1 min of pre-incubation. In addition, C10C was capable of inhibiting in vitro growth of Vibrio splendidus LGP32 (MIC 125 microM), Vibrio anguillarum (MIC 2mM), Micrococcus lysodeikticus and Escherichia coli (MIC 1mM). Destroying the cysteine-stabilized alphabeta structure or shortening the C10C fragment to the C6C fragment with only one disulfide bond resulted in loss of both antiviral and antibacterial activities. Increasing the positive net charge did not enforce the antibacterial activity and completely suppressed the antiviral one. The C10C-designed peptide from mytilin appeared comparable in composition and structure with protegrin, tachyplesin and polyphemusin.

  18. Cloning, expression, and antiviral activity of interferon β from the Chinese microbat, Myotis davidii

    Institute of Scientific and Technical Information of China (English)

    Ying-Zi Liang; Li-Jun Wu; Qian Zhang; Peng Zhou; Mei-Niang Wang; Xing-Lou Yang; Xing-Yi Ge; Lin-Fa Wang; Zheng-Li Shi

    2015-01-01

    Bats are natural reservoir hosts for many viruses that produce no clinical symptoms in bats.Therefore, bats may have evolved effective mechanisms to control viral replication. However, little information is available on bat immune responses to viral infection. Type I interferon(IFN) plays a key role in controlling viral infections. In this study, we report the cloning, expression, and biological activity of interferon β(IFNβ) from the Chinese microbat species, Myotis davidii. We demonstrated the upregulation of IFNB and IFN-stimulated genes in a kidney cell line derived from M. davidii after treatment with poly I:C or infection with Sendai virus. Furthermore, the recombinant IFNβ inhibited vesicular stomatitis virus and bat adenovirus replication in cell lines from two bat species, M. davidii and Rhinolophus sinicus. We provide the first in vitro evidence of IFNβ antiviral activity in microbats, which has important implications for virus interactions with these hosts.

  19. Antimicrobial, antiviral and cytotoxic activity of extracts and constituents from Polygonum spectabile Mart.

    Science.gov (United States)

    Brandão, Geraldo Célio; Kroon, Erna Gessien; Duarte, Maria Gorette R; Braga, Fernão Castro; de Souza Filho, José Dias; de Oliveira, Alaíde Braga

    2010-10-01

    Polygonum spectabile is used in Brazil for treatment of several infection diseases. Extracts and constituents isolated from this species were evaluated for cytotoxicity and effects on 15 bacterias and yeasts as well on 4 viruses strains (HHV-1, VACV-WR, EMCV, DEN-2). Less polar extracts were effective against Staphylococcus aureus, Bacillus subtillis, Micrococcus luteus, M. canis and Tricophyton mentagrophytes and T. rubrum. Two known chalcones and 3-O-β-D-glucosyl-β-sitosterol were isolated. The ethanol extract was the only one to show antiviral activity (CE50 chalcone has inhibited the growth of several bacteria and was significantly active against dermathophytes. The 3 compounds isolated have shown moderate cytotoxicity against Vero and LLCMK(2) cells (CC(50) antimicrobial agent.

  20. Epimedium koreanum Nakai Water Extract Exhibits Antiviral Activity against Porcine Epidermic Diarrhea Virus In Vitro and In Vivo

    Directory of Open Access Journals (Sweden)

    Won-Kyung Cho

    2012-01-01

    Full Text Available Porcine epidemic diarrhea virus (PEDV causes diarrhea of pigs age-independently and death of young piglets, resulting in economic loss of porcine industry. We have screened 333 natural oriental herbal medicines to search for new antiviral candidates against PEDV. We found that two herbal extracts, KIOM 198 and KIOM 124, contain significant anti-PED viral effect. KIOM 198 and KIOM 124 were identified as Epimedium koreanum Nakai and Lonicera japonica Thunberg, respectively. The further plaque and CPE inhibition assay in vitro showed that KIOM 198 has much stronger antiviral activity than KIOM 124. Additionally, KIOM 198 exhibited a similar extent of antiviral effect against other subtypes of Corona virus such as sm98 and TGE viruses. Cytotoxicity results showed that KIOM 198 is nontoxic on the cells and suggest that it can be delivered safely for therapy. Furthermore, when we orally administered KIOM 198 to piglets and then infected them with PEDV, the piglets did not show any disease symptoms like diarrhea and biopsy results showed clean intestine, whereas control pigs without KIOM 198 treatment exhibited PED-related severe symptoms. These results imply that KIOM 198 contains strong antiviral activity and has a potential to be developed as an antiviral phytomedicine to treat PEDV-related diseases in pigs.

  1. Antiviral activity of a small molecule deubiquitinase inhibitor occurs via induction of the unfolded protein response.

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    Jeffrey W Perry

    Full Text Available Ubiquitin (Ub is a vital regulatory component in various cellular processes, including cellular responses to viral infection. As obligate intracellular pathogens, viruses have the capacity to manipulate the ubiquitin (Ub cycle to their advantage by encoding Ub-modifying proteins including deubiquitinases (DUBs. However, how cellular DUBs modulate specific viral infections, such as norovirus, is poorly understood. To examine the role of DUBs during norovirus infection, we used WP1130, a small molecule inhibitor of a subset of cellular DUBs. Replication of murine norovirus in murine macrophages and the human norovirus Norwalk virus in a replicon system were significantly inhibited by WP1130. Chemical proteomics identified the cellular DUB USP14 as a target of WP1130 in murine macrophages, and pharmacologic inhibition or siRNA-mediated knockdown of USP14 inhibited murine norovirus infection. USP14 is a proteasome-associated DUB that also binds to inositol-requiring enzyme 1 (IRE1, a critical mediator of the unfolded protein response (UPR. WP1130 treatment of murine macrophages did not alter proteasome activity but activated the X-box binding protein-1 (XBP-1 through an IRE1-dependent mechanism. In addition, WP1130 treatment or induction of the UPR also reduced infection of other RNA viruses including encephalomyocarditis virus, Sindbis virus, and La Crosse virus but not vesicular stomatitis virus. Pharmacologic inhibition of the IRE1 endonuclease activity partially rescued the antiviral effect of WP1130. Taken together, our studies support a model whereby induction of the UPR through cellular DUB inhibition blocks specific viral infections, and suggest that cellular DUBs and the UPR represent novel targets for future development of broad spectrum antiviral therapies.

  2. Antiviral Activity of Nano Carbon Fullerene Lipidosome against Influenza Virus/In Vitro

    Institute of Scientific and Technical Information of China (English)

    Hong JI; Zhanqiu YANG; Wenling JIANG; Chun GENG; Ming GONG; Hong XIAO; Zhijie WANG; Li CHENG

    2008-01-01

    The activity of nano carbon fullerene lipidosome (NCFL) against influenza virus HINI in vitro was studied by observing the cytotoxicities and its activity rendered by different intensities of lighting with various periods of time. Rimantadine hydrochloride was used as the positive control drug. By using microcultural technique, the morphological changes of cells were observed and by using the gentian violet staining, antiviral activity of the NCFL against influenza virus was assayed. The results showed that: (1) The maximal concentration of the NCFL was 7μg/mL and the 50% toxic concentration (TC50) was 13.54μg/mL respectively; (2) NCFL had a significant activity of directly killing the influenza virus, while the activities in antiadsorption and antireplication were not obvious; (3) There was a dose-activity relationship between the dosages of NCFL and the direct killing effect against the influenza virus, and the periods of lighting-time could influence the activity partly. It was concluded that NCFL had a significant activity of directly killing the influenza virus.

  3. Antiviral immunity of Anopheles gambiae is highly compartmentalized, with distinct roles for RNA interference and gut microbiota.

    Science.gov (United States)

    Carissimo, Guillaume; Pondeville, Emilie; McFarlane, Melanie; Dietrich, Isabelle; Mitri, Christian; Bischoff, Emmanuel; Antoniewski, Christophe; Bourgouin, Catherine; Failloux, Anna-Bella; Kohl, Alain; Vernick, Kenneth D

    2015-01-13

    Arboviruses are transmitted by mosquitoes and other arthropods to humans and animals. The risk associated with these viruses is increasing worldwide, including new emergence in Europe and the Americas. Anopheline mosquitoes are vectors of human malaria but are believed to transmit one known arbovirus, o'nyong-nyong virus, whereas Aedes mosquitoes transmit many. Anopheles interactions with viruses have been little studied, and the initial antiviral response in the midgut has not been examined. Here, we determine the antiviral immune pathways of the Anopheles gambiae midgut, the initial site of viral infection after an infective blood meal. We compare them with the responses of the post-midgut systemic compartment, which is the site of the subsequent disseminated viral infection. Normal viral infection of the midgut requires bacterial flora and is inhibited by the activities of immune deficiency (Imd), JAK/STAT, and Leu-rich repeat immune factors. We show that the exogenous siRNA pathway, thought of as the canonical mosquito antiviral pathway, plays no detectable role in antiviral defense in the midgut but only protects later in the systemic compartment. These results alter the prevailing antiviral paradigm by describing distinct protective mechanisms in different body compartments and infection stages. Importantly, the presence of the midgut bacterial flora is required for full viral infectivity to Anopheles, in contrast to malaria infection, where the presence of the midgut bacterial flora is required for protection against infection. Thus, the enteric flora controls a reciprocal protection tradeoff in the vector for resistance to different human pathogens.

  4. Early gene activation initiates neuroinflammation prior to VSV neuroinvasion: Impact on antiviral responses and sleep.

    Science.gov (United States)

    Ciavarra, Richard P; Lundberg, Patric; Machida, Mayumi; Ambrozewicz, Marta A; Wellman, Laurie L; Breving, Kimberly; Steel, Christina; Sanford, Larry D

    2017-02-15

    Rapid eye movement (REM) sleep is rapidly and persistently suppressed during vesicular stomatitis virus (VSV) encephalitis in C57Bl/6J (B6) mice. REM sleep suppression was associated with a complex global brain chemokine/cytokine response with bimodal kinetics although regionally distinct cytokine profiles were readily identified. Cytokine mRNA was translated either immediately or suppressed until the pathogen was cleared from the CNS. Innate signaling pathway (TLRs, RIG-I) activation occurred rapidly and sequentially prior to VSV neuroinvasion suggesting that antiviral states are quickly established in the CNS in advance of viral pathogen penetration. Il1β suppressed REM sleep mimicking aspects of VSV-induced sleep alterations whereas some robustly induced chemokines may be protective of REM. Thus, multiple brain chemokines may mediate sleep across VSV encephalitis via differential somnogenic effects.

  5. MAVS recruits multiple ubiquitin E3 ligases to activate antiviral signaling cascades

    Science.gov (United States)

    Liu, Siqi; Chen, Jueqi; Cai, Xin; Wu, Jiaxi; Chen, Xiang; Wu, You-Tong; Sun, Lijun; Chen, Zhijian J

    2013-01-01

    RNA virus infections are detected by the RIG-I family of receptors, which induce type-I interferons through the mitochondrial protein MAVS. MAVS forms large prion-like polymers that activate the cytosolic kinases IKK and TBK1, which in turn activate NF-κB and IRF3, respectively, to induce interferons. Here we show that MAVS polymers recruit several TRAF proteins, including TRAF2, TRAF5, and TRAF6, through distinct TRAF-binding motifs. Mutations of these motifs that disrupted MAVS binding to TRAFs abrogated its ability to activate IRF3. IRF3 activation was also abolished in cells lacking TRAF2, 5, and 6. These TRAF proteins promoted ubiquitination reactions that recruited NEMO to the MAVS signaling complex, leading to the activation of IKK and TBK1. These results delineate the mechanism of MAVS signaling and reveal that TRAF2, 5, and 6, which are normally associated with NF-κB activation, also play a crucial role in IRF3 activation in antiviral immune responses. DOI: http://dx.doi.org/10.7554/eLife.00785.001 PMID:23951545

  6. Coxsackievirus cloverleaf RNA containing a 5' triphosphate triggers an antiviral response via RIG-I activation

    NARCIS (Netherlands)

    Feng, Qian; Langereis, Martijn A; Olagnier, David; Chiang, Cindy; van de Winkel, Roel; van Essen, Peter; Zoll, Jan; Hiscott, John; van Kuppeveld, Frank J M

    2014-01-01

    Upon viral infections, pattern recognition receptors (PRRs) recognize pathogen-associated molecular patterns (PAMPs) and stimulate an antiviral state associated with the production of type I interferons (IFNs) and inflammatory markers. Type I IFNs play crucial roles in innate antiviral responses by

  7. Antiviral activity of extracts from Brazilian seaweeds against herpes simplex virus

    Directory of Open Access Journals (Sweden)

    Angélica Ribeiro Soares

    2012-08-01

    Full Text Available Organic extracts of 36 species of marine algae (sixteen species of Rhodophyta, eight species of Ochrophyta and twelve species of Chlorophyta from seven locations on the Brazilian coast were evaluated for their anti-HSV-1 and anti-HSV-2 activity resistant to Acyclovir (ACV. Activity tests in crude extracts, followed by the identification of the major compounds present, were performed for all species. The chemical profiles of all crude extracts were obtained by ¹H-NMR and 13C-NMR spectroscopy. The percentage of extracts with antiviral activity was higher for HSV-1 (86.1% than for HSV-2 (55.5%. The green algae Ulva fasciata and Codium decorticatum both showed the highest activity (99.9% against HSV-1, with triacylglycerols and fatty acids as the major components. The red alga Laurencia dendroidea showed good activity against HSV-1 (97.5% and the halogenated sesquiterpenes obtusol and (--elatol were identified as the major components in the extract. Against HSV-2, the green alga Penicillus capitatus (Chlorophyta and Stypopodium zonale (Ochrophyta were the most active (96.0 and 95.8%. Atomaric acid, a meroditerpene, was identified as the major secondary metabolite in the S. zonale extract. These results reinforce the role of seaweeds as important sources of compounds with the potential to enter into the pipeline for development of new drugs against herpes simplex.

  8. Immunostimulatory motifs enhance antiviral siRNAs targeting highly pathogenic avian influenza H5N1.

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    Cameron R Stewart

    Full Text Available Highly pathogenic avian influenza (HPAI H5N1 virus is endemic in many regions around the world and remains a significant pandemic threat. To date H5N1 has claimed almost 300 human lives worldwide, with a mortality rate of 60% and has caused the death or culling of hundreds of millions of poultry since its initial outbreak in 1997. We have designed multi-functional RNA interference (RNAi-based therapeutics targeting H5N1 that degrade viral mRNA via the RNAi pathway while at the same time augmenting the host antiviral response by inducing host type I interferon (IFN production. Moreover, we have identified two factors critical for maximising the immunostimulatory properties of short interfering (siRNAs in chicken cells (i mode of synthesis and (ii nucleoside sequence to augment the response to virus. The 5-bp nucleoside sequence 5'-UGUGU-3' is a key determinant in inducing high levels of expression of IFN-α, -β, -λ and interleukin 1-β in chicken cells. Positioning of this 5'-UGUGU-3' motif at the 5'-end of the sense strand of siRNAs, but not the 3'-end, resulted in a rapid and enhanced induction of type I IFN. An anti-H5N1 avian influenza siRNA directed against the PB1 gene (PB1-2257 tagged with 5'-UGUGU-3' induced type I IFN earlier and to a greater extent compared to a non-tagged PB1-2257. Tested against H5N1 in vitro, the tagged PB1-2257 was more effective than non-tagged PB1-2257. These data demonstrate the ability of an immunostimulatory motif to improve the performance of an RNAi-based antiviral, a finding that may influence the design of future RNAi-based anti-influenza therapeutics.

  9. Tolerance and antiviral effects of high-dose interferon-alpha B/D in patients with chronic hepatitis B

    NARCIS (Netherlands)

    Rasch, MC; Schellekens, H; van Dijck, CMM; Haagsma, EB; Michielsen, PP; van Buuren, AHJAM; Stotter, H; van Hattum, J

    1998-01-01

    A novel recombinant interferon-alpha B/D hybrid was applied to assess tolerability, antiviral effect, and biological activity in chronic hepatitis B. The study was designed as an open nonrandomized trial. Treatment comprised a two-week run-in phase with 16 MU three times a week followed by 14 weeks

  10. An important role for type III interferon (IFN-lambda/IL-28) in TLR-induced antiviral activity

    DEFF Research Database (Denmark)

    Ank, Nina; Iversen, Marie B; Bartholdy, Christina

    2008-01-01

    Type III IFNs (IFN-lambda/IL-28/29) are cytokines with type I IFN-like antiviral activities, which remain poorly characterized. We herein show that most cell types expressed both types I and III IFNs after TLR stimulation or virus infection, whereas the ability of cells to respond to IFN-lambda w...

  11. An important role for type III interferon (IFN-lambda/IL-28) in TLR-induced antiviral activity

    DEFF Research Database (Denmark)

    Ank, Nina; Iversen, Marie B; Bartholdy, Christina;

    2008-01-01

    Type III IFNs (IFN-lambda/IL-28/29) are cytokines with type I IFN-like antiviral activities, which remain poorly characterized. We herein show that most cell types expressed both types I and III IFNs after TLR stimulation or virus infection, whereas the ability of cells to respond to IFN-lambda w...

  12. Actinobacteria from Termite Mounds Show Antiviral Activity against Bovine Viral Diarrhea Virus, a Surrogate Model for Hepatitis C Virus

    Directory of Open Access Journals (Sweden)

    Marina Aiello Padilla

    2015-01-01

    Full Text Available Extracts from termite-associated bacteria were evaluated for in vitro antiviral activity against bovine viral diarrhea virus (BVDV. Two bacterial strains were identified as active, with percentages of inhibition (IP equal to 98%. Both strains were subjected to functional analysis via the addition of virus and extract at different time points in cell culture; the results showed that they were effective as posttreatments. Moreover, we performed MTT colorimetric assays to identify the CC50, IC50, and SI values of these strains, and strain CDPA27 was considered the most promising. In parallel, the isolates were identified as Streptomyces through 16S rRNA gene sequencing analysis. Specifically, CDPA27 was identified as S. chartreusis. The CDPA27 extract was fractionated on a C18-E SPE cartridge, and the fractions were reevaluated. A 100% methanol fraction was identified to contain the compound(s responsible for antiviral activity, which had an SI of 262.41. GC-MS analysis showed that this activity was likely associated with the compound(s that had a peak retention time of 5 min. Taken together, the results of the present study provide new information for antiviral research using natural sources, demonstrate the antiviral potential of Streptomyces chartreusis compounds isolated from termite mounds against BVDV, and lay the foundation for further studies on the treatment of HCV infection.

  13. Antiviral activity of α-helical stapled peptides designed from the HIV-1 capsid dimerization domain

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    Cowburn David

    2011-05-01

    Full Text Available Abstract Background The C-terminal domain (CTD of HIV-1 capsid (CA, like full-length CA, forms dimers in solution and CTD dimerization is a major driving force in Gag assembly and maturation. Mutations of the residues at the CTD dimer interface impair virus assembly and render the virus non-infectious. Therefore, the CTD represents a potential target for designing anti-HIV-1 drugs. Results Due to the pivotal role of the dimer interface, we reasoned that peptides from the α-helical region of the dimer interface might be effective as decoys to prevent CTD dimer formation. However, these small peptides do not have any structure in solution and they do not penetrate cells. Therefore, we used the hydrocarbon stapling technique to stabilize the α-helical structure and confirmed by confocal microscopy that this modification also made these peptides cell-penetrating. We also confirmed by using isothermal titration calorimetry (ITC, sedimentation equilibrium and NMR that these peptides indeed disrupt dimer formation. In in vitro assembly assays, the peptides inhibited mature-like virus particle formation and specifically inhibited HIV-1 production in cell-based assays. These peptides also showed potent antiviral activity against a large panel of laboratory-adapted and primary isolates, including viral strains resistant to inhibitors of reverse transcriptase and protease. Conclusions These preliminary data serve as the foundation for designing small, stable, α-helical peptides and small-molecule inhibitors targeted against the CTD dimer interface. The observation that relatively weak CA binders, such as NYAD-201 and NYAD-202, showed specificity and are able to disrupt the CTD dimer is encouraging for further exploration of a much broader class of antiviral compounds targeting CA. We cannot exclude the possibility that the CA-based peptides described here could elicit additional effects on virus replication not directly linked to their ability to bind

  14. Antiviral Activity of Ctn[15-34], A Cathelicidin-Derived Eicosapeptide, Against Infectious Myonecrosis Virus in Litopenaeus vannamei Primary Hemocyte Cultures.

    Science.gov (United States)

    Vieira-Girão, P R N; Falcão, C B; Rocha, I R C B; Lucena, H M R; Costa, F H F; Rádis-Baptista, G

    2017-02-16

    The shrimp farming has been converted into a mature aquaculture industry dealing with over millions of metric tonnes of processed commodities. Nevertheless, the global shrimp productions are constantly threatened by disease outbreaks, mainly triggered by rapidly disseminating viruses. Infectious myonecrosis virus (IMNV) is one of these epizootic agents affecting shrimp production in Brazil, of which no treatment exists. Herein, the antiviral activity against IMNV of an eicosapeptide, named Ctn[15-34], derived from a member of the cathelicidin family of antimicrobial peptides, was demonstrated. Cultures of hemocytes from Litopenaeus vannamei were established that support IMNV replication and infectivity titration. The cytotoxic effect of IMNV in culture and the in vitro anti-IMNV activity of Ctn[15-34] were assessed using a high-sensitive fluorescent-based method in combination with quantitative PCR. The Ctn[15-34] (shrimp hemocytes. This study reported for the first time the replication of IMNV in vitro and the employment of a straightforward methodology to assess cell viability and viral/antiviral activities. In addition, it provided the basis for the development of the anti-infective multi-effector Ctn[15-34] eicosapeptide and analogs as components of antiviral formulations against shrimp viral diseases.

  15. Chemical composition of 8 eucalyptus species' essential oils and the evaluation of their antibacterial, antifungal and antiviral activities

    Directory of Open Access Journals (Sweden)

    Elaissi Ameur

    2012-06-01

    Full Text Available Abstract Background In 1957, Tunisia introduced 117 species of Eucalyptus; they have been used as fire wood, for the production of mine wood and to fight erosion. Actually, Eucalyptus essential oil is traditionally used to treat respiratory tract disorders such as pharyngitis, bronchitis, and sinusitis. A few investigations were reported on the biological activities of Eucalyptus oils worldwide. In Tunisia, our previous works conducted in 2010 and 2011 had been the first reports to study the antibacterial activities against reference strains. At that time it was not possible to evaluate their antimicrobial activities against clinical bacterial strains and other pathogens such as virus and fungi. Methods The essential oils of eight Eucalyptus species harvested from the Jbel Abderrahman, Korbous (North East Tunisia and Souinet arboreta (North of Tunisia were evaluated for their antimicrobial activities by disc diffusion and microbroth dilution methods against seven bacterial isolates: Haemophilus influenzae, Klebsiella pneumoniae, Pseudomonas aeruginosa, Staphylococcus aureus, Streptococcus agalactiae, Streptococcus pneumoniae and Streptococcus pyogenes. In addition, the bactericidal, fungicidal and the antiviral activities of the tested oils were carried out. Results Twenty five components were identified by GC/FID and GC/MS. These components were used to correlate with the biological activities of the tested oils. The chemical principal component analysis identified three groups, each of them constituted a chemotype. According to the values of zone diameter and percentage of the inhibition (zdi, % I, respectively, four groups and subgroups of bacterial strains and three groups of fungal strains were characterized by their sensitivity levels to Eucalyptus oils. The cytotoxic effect and the antiviral activity varied significantly within Eucalyptus species oils. Conclusions E. odorata showed the strongest activity against S. aureus, H. influenzae

  16. Chemical composition of 8 eucalyptus species' essential oils and the evaluation of their antibacterial, antifungal and antiviral activities

    Science.gov (United States)

    2012-01-01

    Background In 1957, Tunisia introduced 117 species of Eucalyptus; they have been used as fire wood, for the production of mine wood and to fight erosion. Actually, Eucalyptus essential oil is traditionally used to treat respiratory tract disorders such as pharyngitis, bronchitis, and sinusitis. A few investigations were reported on the biological activities of Eucalyptus oils worldwide. In Tunisia, our previous works conducted in 2010 and 2011 had been the first reports to study the antibacterial activities against reference strains. At that time it was not possible to evaluate their antimicrobial activities against clinical bacterial strains and other pathogens such as virus and fungi. Methods The essential oils of eight Eucalyptus species harvested from the Jbel Abderrahman, Korbous (North East Tunisia) and Souinet arboreta (North of Tunisia) were evaluated for their antimicrobial activities by disc diffusion and microbroth dilution methods against seven bacterial isolates: Haemophilus influenzae, Klebsiella pneumoniae, Pseudomonas aeruginosa, Staphylococcus aureus, Streptococcus agalactiae, Streptococcus pneumoniae and Streptococcus pyogenes. In addition, the bactericidal, fungicidal and the antiviral activities of the tested oils were carried out. Results Twenty five components were identified by GC/FID and GC/MS. These components were used to correlate with the biological activities of the tested oils. The chemical principal component analysis identified three groups, each of them constituted a chemotype. According to the values of zone diameter and percentage of the inhibition (zdi, % I, respectively), four groups and subgroups of bacterial strains and three groups of fungal strains were characterized by their sensitivity levels to Eucalyptus oils. The cytotoxic effect and the antiviral activity varied significantly within Eucalyptus species oils. Conclusions E. odorata showed the strongest activity against S. aureus, H. influenzae, S. agalactiae, S. pyogenes

  17. Zebrafish ISG15 Exerts a Strong Antiviral Activity against RNA and DNA Viruses and Regulates the Interferon Response

    NARCIS (Netherlands)

    Langevin, C.; Aa, van der L.M.; Houel, A.; Torhy, C.; Briolat, V.; Lunazzi, A.; Harmache, A.; Bremont, M.; Levraud, J.P.; Boudinot, P.

    2013-01-01

    ISG15, a 15-kDa interferon-induced protein that participates in antiviral defenses of mammals, is highly conserved among vertebrates. In fish, as in mammals, viral infection and interferon treatment induce isg15 expression. The two ubiquitin-like domains of ISG15 and the presence of a consensus LRLR

  18. Gas chromatography-mass spectroscopy analysis of bioactive petalostigma extracts: Toxicity, antibacterial and antiviral activities

    Directory of Open Access Journals (Sweden)

    F R Kalt

    2014-01-01

    Full Text Available Background: Petalostigma pubescens and Petalostigma triloculare were common components of pharmacopeia′s of multiple Australian Aboriginal tribal groupings which traditionally inhabited the areas in which they grow. Among these groups, they had a myriad of medicinal uses in treating a wide variety of bacterial, fungal and viral infections. This study was undertaken to test P. pubescens and P. triloculare leaf and fruit extracts for the ability to inhibit bacterial and viral growth and thus validate Australian Aboriginal usage of these plants in treating bacterial and fungal diseases. Materials and Methods: P. pubescens, and P. triloculare leaves and fruit were extracted and tested for antimicrobial, antiviral activity and toxicity. The bioactive extracts were further examined by RP-HPLC and GC-MS to identify the component compounds. Results: The methanol, water and ethyl acetate leaf and fruit extracts of displayed potent antibacterial activity. The methanol and ethyl acetate extracts displayed the broadest specificity, inhibiting the growth of 10 of the 14 bacteria tested (71% for the leaf extract and 9 of the 14 bacteria tested (64% for the fruit extracts. The water extracts also had broad spectrum antibacterial activity, inhibiting the growth of 8 (57% and 7 (50% of the 14 bacteria tested, respectively. All antibacterial extracts were approximately equally effective against Gram-positive and Gram-negative bacteria, inhibiting the growth of 50-75% of the bacteria tested. The methanol, water and ethyl acetate extracts also displayed antiviral activity in the MS2 plaque reduction assay. The methanol and water extracts inhibited 26.6-49.0% and 85.4-97.2% of MS2 plaque formation, respectively, with the fruit extracts being more potent inhibitors. All ethyl acetate extracts inhibited 100% of MS2 plaque formation. All extracts were also non-toxic or of low toxicity. Analysis of these extracts by RP-HPLC showed that the P. triloculare ethyl acetate

  19. Benzophenone C-glucosides and gallotannins from mango tree stem bark with broad-spectrum anti-viral activity.

    Science.gov (United States)

    Abdel-Mageed, Wael M; Bayoumi, Soad A H; Chen, Caixia; Vavricka, Christopher J; Li, Li; Malik, Ajamaluddin; Dai, Huanqin; Song, Fuhang; Wang, Luoqiang; Zhang, Jingyu; Gao, George F; Lv, Yali; Liu, Lihong; Liu, Xueting; Sayed, Hanaa M; Zhang, Lixin

    2014-04-01

    The high mutation rate of RNA viruses has resulted in limitation of vaccine effectiveness and increased emergence of drug-resistant viruses. New effective antivirals are therefore needed to control of the highly mutative RNA viruses. The n-butanol fraction of the stem bark of Mangifera indica exhibited inhibitory activity against influenza neuraminidase (NA) and coxsackie virus 3C protease. Bioassay guided phytochemical study of M. indica stem bark afforded two new compounds including one benzophenone C-glycoside (4) and one xanthone dimer (7), together with eleven known compounds. The structures of these isolated compounds were elucidated on the basis of spectroscopic evidences and correlated with known compounds. Anti-influenza and anti-coxsackie virus activities were evaluated by determining the inhibition of anti-influenza neuraminidase (NA) from pandemic A/RI/5+/1957 H2N2 influenza A virus and inhibition of coxsackie B3 virus 3C protease, respectively. The highest anti-influenza activity was observed for compounds 8 and 9 with IC50 values of 11.9 and 9.2μM, respectively. Compounds 8 and 9 were even more potent against coxsackie B3 virus 3C protease, with IC50 values of 1.1 and 2.0μM, respectively. Compounds 8 and 9 showed weak cytotoxic effect against human hepatocellular carcinoma and human epithelial carcinoma cell lines through MTT assay.

  20. Atividade antiviral do extrato de própolis contra o calicivírus felino, adenovírus canino 2 e vírus da diarréia viral bovina Antiviral activity of propolis extracts against feline calicivirus, canine adenovirus 2, and bovine viral diarrhea virus

    Directory of Open Access Journals (Sweden)

    Ana Paula Cueto

    2011-10-01

    Maria (RS region, while the other was bought from a Minas Gerais industry. The high efficiency liquid cromatography (HPLC analysis detected the presence of some flavonoids like rutin, quercetin, and gallic acid. The MTT test was applied in order to detect the citotoxicity and also the antiviral activity. Both extracts showed antiviral activity against BVDV and CAV-2 when incubated with the cell cultures before viral inoculation. The extracts were less effective against FCV comparing to the results for the other viruses and, the antiviral activity was observed only when the própolis was present after virus inoculation The extract obtained in the lab showed the highest selectivity index (SI= CC50/ EC50. Thus, propolis showed antiviral activity against three different viruses, making it a target for the development of new natural compounds with antiviral activity.

  1. Antiviral Activity of Fridericia formosa (Bureau L. G. Lohmann (Bignoniaceae Extracts and Constituents

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    Geraldo Célio Brandão

    2017-01-01

    Full Text Available A phytochemical study of Fridericia formosa (Bignoniaceae ethanol extracts of leaves, stems, and fruits was guided by in vitro assays against vaccinia virus Western Reserve (VACV-WR, human herpes virus 1 (HSV-1, murine encephalomyocarditis virus (EMCV, and dengue virus type 2 (DENV-2 by the MTT method. All the ethanol extracts were active against DENV-2, HSV-1, and VACV-WR with best results for the fruits extract against DENV-2 (SI > 38.2. For VACV-WR and HSV-1, EC50 values > 200 μg mL−1 were determined, while no inhibition of the cytopathic effect was observed with EMCV. Five compounds were isolated and identified as the C-glucosylxanthones mangiferin (1, 2′-O-trans-caffeoylmangiferin (2, 2′-O-trans-coumaroylmangiferin (3, 2′-O-trans-cinnamoylmangiferin (5, and the flavonoid chrysin (4. The most active compound was 2′-O-trans-coumaroylmangiferin (3 with SI > 121.9 against DENV-2 and 108.7 for HSV-1. These results indicate that mangiferin cinnamoyl esters might be potential antiviral drugs.

  2. Mx Is Not Responsible for the Antiviral Activity of Interferon-α against Japanese Encephalitis Virus

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    Jing Zhou

    2017-01-01

    Full Text Available Mx proteins are interferon (IFN-induced dynamin-like GTPases that are present in all vertebrates and inhibit the replication of myriad viruses. However, the role Mx proteins play in IFN-mediated suppression of Japanese encephalitis virus (JEV infection is unknown. In this study, we set out to investigate the effects of Mx1 and Mx2 expression on the interferon-α (IFNα restriction of JEV replication. To evaluate whether the inhibitory activity of IFNα on JEV is dependent on Mx1 or Mx2, we knocked down Mx1 or Mx2 with siRNA in IFNα-treated PK-15 cells and BHK-21 cells, then challenged them with JEV; the production of progeny virus was assessed by plaque assay, RT-qPCR, and Western blotting. Our results demonstrated that depletion of Mx1 or Mx2 did not affect JEV restriction imposed by IFNα, although these two proteins were knocked down 66% and 79%, respectively. Accordingly, expression of exogenous Mx1 or Mx2 did not change the inhibitory activity of IFNα to JEV. In addition, even though virus-induced membranes were damaged by Brefeldin A (BFA, overexpressing porcine Mx1 or Mx2 did not inhibit JEV proliferation. We found that BFA inhibited JEV replication, not maturation, suggesting that BFA could be developed into a novel antiviral reagent. Collectively, our findings demonstrate that IFNα inhibits JEV infection by Mx-independent pathways.

  3. Study of the Biological Activity of Novel Synthetic Compounds with Antiviral Properties against Human Rhinoviruses

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    Raffaello Pompei

    2011-04-01

    Full Text Available Picornaviridae represent a very large family of small RNA viruses, some of which are the cause of important human and animal diseases. Since no specific therapy against any of these viruses currently exists, palliative symptomatic treatments are employed. The early steps of the picornavirus replicative cycle seem to be privileged targets for some antiviral compounds like disoxaril and pirodavir. Pirodavir’s main weakness is its cytotoxicity on cell cultures at relatively low doses. In this work some original synthetic compounds were tested, in order to find less toxic compounds with an improved protection index (PI on infected cells. Using an amino group to substitute the oxygen atom in the central chain, such as that in the control molecule pirodavir, resulted in decreased activity against Rhinoviruses and Polioviruses. The presence of an -ethoxy-propoxy- group in the central chain (as in compound I-6602 resulted in decreased cell toxicity and in improved anti-Rhinovirus activity. This compound actually showed a PI >700 on HRV14, while pirodavir had a PI of 250. These results demonstrate that modification of pirodavir’s central hydrocarbon chain can lead to the production of novel derivatives with low cytotoxicity and improved PI against some strains of Rhinoviruses.

  4. In Vitro Antiviral Activity of Clove and Ginger Aqueous Extracts against Feline Calicivirus, a Surrogate for Human Norovirus.

    Science.gov (United States)

    Aboubakr, Hamada A; Nauertz, Andrew; Luong, Nhungoc T; Agrawal, Shivani; El-Sohaimy, Sobhy A A; Youssef, Mohammed M; Goyal, Sagar M

    2016-06-01

    Foodborne viruses, particularly human norovirus, are a concern for public health, especially in fresh vegetables and other minimally processed foods that may not undergo sufficient decontamination. It is necessary to explore novel nonthermal techniques for preventing foodborne viral contamination. In this study, aqueous extracts of six raw food materials (flower buds of clove, fenugreek seeds, garlic and onion bulbs, ginger rhizomes, and jalapeño peppers) were tested for antiviral activity against feline calicivirus (FCV) as a surrogate for human norovirus. The antiviral assay was performed using dilutions of the extracts below the maximum nontoxic concentrations of the extracts to the host cells of FCV, Crandell-Reese feline kidney (CRFK) cells. No antiviral effect was seen when the host cells were pretreated with any of the extracts. However, pretreatment of FCV with nondiluted clove and ginger extracts inactivated 6.0 and 2.7 log of the initial titer of the virus, respectively. Also, significant dosedependent inactivation of FCV was seen when host cells were treated with clove and ginger extracts at the time of infection or postinfection at concentrations equal to or lower than the maximum nontoxic concentrations. By comprehensive two-dimensional gas chromatography-mass spectrometry analysis, eugenol (29.5%) and R-(-)-1,2-propanediol (10.7%) were identified as the major components of clove and ginger extracts, respectively. The antiviral effect of the pure eugenol itself was tested; it showed antiviral activity similar to that of clove extract, albeit at a lower level, which indicates that some other clove extract constituents, along with eugenol, are responsible for inactivation of FCV. These results showed that the aqueous extracts of clove and ginger hold promise for prevention of foodborne viral contamination.

  5. Antiviral activity of bovine uterus and placenta induced by Newcastle disease virus Atividade antiviral do útero e da placenta bovina induzida pelo vírus da doença de Newcastle

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    J.B. Barreto Filho

    2007-06-01

    Full Text Available The antiviral activity profile of the uterus and fetal membranes from bovine placenta, induced by the Newcastle disease virus (NDV throughout gestation, was investigated. Explants of the endometrium and caruncles were collected from the uterus, and amniochorion, allantochorion and cotyledons, from fetal placenta. Tissue cultures were induced with ~6.0 hemagglutinating units (HU of NDV. Supernatants were concentrated 20 fold, filtered in 100kDa cut-off membranes and antiviral activity was titrated in MDBK x VSV system. Tissues of the uterus did not exhibit antiviral activity, while allantochorion and amniochorion produced antiviral factors throughout gestation. Antiviral factors were not related with IFN-alpha, gamma, tau or TNF-alpha. The antiviral activity pattern observed showed to be related with the development of fetal membranes and increased at the end of pregnancy. Such data suggest that IFN genes inducible by virus are present in fetal membranes of the cow placenta and their expression is dependent on the age of gestation.Investigou-se a atividade antiviral do útero e da placenta bovina, ao longo da gestação, induzidos pelo vírus da doença de Newcastle (NDV. Explantes do endométrio e carúnculas foram colhidos do útero. Os tecidos corioamniótico, corioalantóide e cotilédones foram dissecados da placenta fetal. Os cultivos celulares foram induzidos com aproximadamente 6,0 unidades hemaglutinantes do NDV. Os sobrenadantes foram concentrados 20 vezes, filtrados em dispositivos com superfície de separação de 100kDa e a atividade antiviral foi titulada em células MDBK e vírus da estomatite vesicular (VSV. Endométrio, carúnculas e cotilédones não apresentaram atividade antiviral. Corioamniótico e corioalantóide produziram fatores antivirais ao longo da gestação. Estes fatores não foram relacionados aos IFN - alfa, gama ou tau e nem ao TNF - alfa. O padrão de produção de fatores antivirais acompanhou o desenvolvimento

  6. Highly functionalized and potent antiviral cyclopentane derivatives formed by a tandem process consisting of organometallic, transition-metal-catalyzed, and radical reaction steps.

    Science.gov (United States)

    Jagtap, Pratap R; Ford, Leigh; Deister, Elmar; Pohl, Radek; Císařová, Ivana; Hodek, Jan; Weber, Jan; Mackman, Richard; Bahador, Gina; Jahn, Ullrich

    2014-08-11

    A simple modular tandem approach to multiply substituted cyclopentane derivatives is reported, which succeeds by joining organometallic addition, conjugate addition, radical cyclization, and oxygenation steps. The key steps enabling this tandem process are the thus far rarely used isomerization of allylic alkoxides to enolates and single-electron transfer to merge the organometallic step with the radical and oxygenation chemistry. This controlled lineup of multiple electronically contrasting reactive intermediates provides versatile access to highly functionalized cyclopentane derivatives from very simple and readily available commodity precursors. The antiviral activity of the synthesized compounds was screened and a number of compounds showed potent activity against hepatitis C and dengue viruses.

  7. Evaluation of In vitro antiviral activity of Datura metel Linn. against rabies virus

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    Soumen Roy

    2016-01-01

    Full Text Available Objective: The soxhlet and cold extracts of Datura metel Linn. were evaluated for in vitro antirabies activity. Materials and Methods: Soxhlet and cold extraction method were used to extract Datura (fruit and seed extracts. In vitro cytotoxicity assay was performed by 3-(4,5-dimethylthiazolyl-2-2,5-diphenyltetrazolium bromide assay. Based on the CC50 range, the in vitro antirabies activity of the extracts was screened by rapid fluorescent focus inhibition test and molecular method. Results: The Datura (fruit and seed extracts were not cytotoxic below 5 mg/ml (CC50. Titer of 10−4 rabies virus challenge virus standard (RV CVS (1 50% tissue culture infective dose [1 TCID50] was obtained by RFFT method and the challenge dose of 10 TCID50 was used for antirabies assay. Datura fruit and seed (soxhlet and cold extracts showed 50% inhibition of RV CVS at 2.5 mg/ml and 1.25 mg/ml (inhibitory concentration 50% [IC50], respectively. The tested extracts showed selectivity index (CC50/IC50 ranging from 2 to 4. The viral RNA was extracted and real-time reverse transcription-polymerase chain reaction was performed which also revealed a 2-fold reduction of viral load at 1.25 mg/ml of the Datura seed (soxhlet methanolic and cold aqueous extracts. Conclusion: To the best of our knowledge, this is the first study of in vitro antiviral activity of D. metel Linn. against rabies virus. Datura seed extracts have a potential in vitro antirabies activity and, in future, can be further screened for in vivo activity against rabies virus in murine model.

  8. TRIM11 negatively regulates IFNβ production and antiviral activity by targeting TBK1.

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    Younglang Lee

    Full Text Available The innate immune response is a host defense mechanism against infection by viruses and bacteria. Type I interferons (IFNα/β play a crucial role in innate immunity. If not tightly regulated under normal conditions and during immune responses, IFN production can become aberrant, leading to inflammatory and autoimmune diseases. In this study, we identified TRIM11 (tripartite motif containing 11 as a novel negative regulator of IFNβ production. Ectopic expression of TRIM11 decreased IFNβ promoter activity induced by poly (I:C stimulation or overexpression of RIG-I (retinoic acid-inducible gene-I signaling cascade components RIG-IN (constitutively active form of RIG-I, MAVS (mitochondrial antiviral signaling protein, or TBK1 (TANK-binding kinase-1. Conversely, TRIM11 knockdown enhanced IFNβ promoter activity induced by these stimuli. Moreover, TRIM11 overexpression inhibited the phosphorylation and dimerization of IRF3 and expression of IFNβ mRNA. By contrast, TRIM11 knockdown increased the IRF3 phosphorylation and IFNβ mRNA expression. We also found that TRIM11 and TBK1, a key kinase that phosphorylates IRF3 in the RIG-I pathway, interacted with each other through CC and CC2 domain, respectively. This interaction was enhanced in the presence of the TBK1 adaptor proteins, NAP1 (NF-κB activating kinase-associated protein-1, SINTBAD (similar to NAP1 TBK1 adaptor or TANK (TRAF family member-associated NF-κB activator. Consistent with its inhibitory role in RIG-I-mediated IFNβ signaling, TRIM11 overexpression enhanced viral infectivity, whereas TRIM11 knockdown produced the opposite effect. Collectively, our results suggest that TRIM11 inhibits RIG-I-mediated IFNβ production by targeting the TBK1 signaling complex.

  9. Antiviral Activity of Favipiravir (T-705) against a Broad Range of Paramyxoviruses In Vitro and against Human Metapneumovirus in Hamsters.

    Science.gov (United States)

    Jochmans, D; van Nieuwkoop, S; Smits, S L; Neyts, J; Fouchier, R A M; van den Hoogen, B G

    2016-08-01

    The clinical impact of infections with respiratory viruses belonging to the family Paramyxoviridae argues for the development of antiviral therapies with broad-spectrum activity. Favipiravir (T-705) has demonstrated potent antiviral activity against multiple RNA virus families and is presently in clinical evaluation for the treatment of influenza. Here we demonstrate in vitro activity of T-705 against the paramyxoviruses human metapneumovirus (HMPV), respiratory syncytial virus, human parainfluenza virus, measles virus, Newcastle disease virus, and avian metapneumovirus. In addition, we demonstrate activity against HMPV in hamsters. T-705 treatment inhibited replication of all paramyxoviruses tested in vitro, with 90% effective concentration (EC90) values of 8 to 40 μM. Treatment of HMPV-challenged hamsters with T-705 at 200 mg/kg of body weight/day resulted in 100% protection from infection of the lungs. In all treated and challenged animals, viral RNA remained detectable in the respiratory tract. The observation that T-705 treatment had a significant effect on infectious viral titers, with a limited effect on viral genome titers, is in agreement with its proposed mode of action of viral mutagenesis. However, next-generation sequencing of viral genomes isolated from treated and challenged hamsters did not reveal (hyper)mutation. Polymerase activity assays revealed a specific effect of T-705 on the activity of the HMPV polymerase. With the reported antiviral activity of T-705 against a broad range of RNA virus families, this small molecule is a promising broad-range antiviral drug candidate for limiting the viral burden of paramyxoviruses and for evaluation for treatment of infections with (re)emerging viruses, such as the henipaviruses.

  10. Enhancement of antiviral activity of collectin trimers through cross-linking and mutagenesis of the carbohydrate recognition domain

    DEFF Research Database (Denmark)

    White, Mitchell R; Boland, Patrick; Tecle, Tesfaldet

    2010-01-01

    Surfactant protein D (SP-D) plays important roles in innate defense against respiratory viruses [including influenza A viruses (IAVs)]. Truncated trimers composed of its neck and carbohydrate recognition domains (NCRDs) bind various ligands; however, they have minimal inhibitory activity for IAV......Ab have similar effects. Hence, cross-linking activity, but not the Fc domain of the mAb, is needed for increased antiviral activity. In contrast, the Fc domain of the mAb was important for increasing viral uptake or respiratory burst responses of human neutrophils. Our NCRD constructs contain an S......, complementary strategies, namely cross-linking of NCRDs through various means and mutagenesis of CRD residues to increase viral binding. These findings may be relevant for antiviral therapy....

  11. Tetrameric assembly of hGBP1 is crucial for both stimulated GMP formation and antiviral activity.

    Science.gov (United States)

    Pandita, Esha; Rajan, Sudeepa; Rahman, Safikur; Mullick, Ranajoy; Das, Saumitra; Sau, Apurba Kumar

    2016-06-15

    Interferon-γ inducible human guanylate binding protein-1 (hGBP1) shows a unique characteristic that hydrolyses GTP to a mixture of GDP and GMP through successive cleavages, with GMP being the major product. Like other large GTPases, hGBP1 undergoes oligomerization upon substrate hydrolysis, which is essential for the stimulation of activity. It also exhibits antiviral activity against many viruses including hepatitis C. However, which oligomeric form is responsible for the stimulated activity leading to enhanced GMP formation and its influence on antiviral activity, are not properly understood. Using mutant and truncated proteins, our data indicate that transition-state-induced tetramerization is associated with higher rate of GMP formation. This is supported by chimaeras that are defective in both tetramerization and enhanced GMP formation. Unlike wild-type protein, chimaeras did not show allosteric interactions, indicating that tetramerization and enhanced GMP formation are allosterically coupled. Hence, we propose that after the cleavage of the first phosphoanhydride bond GDP·Pi-bound protein dimers transiently associate to form a tetramer that acts as an allosteric switch for higher rate of GMP formation. Biochemical and biophysical studies reveal that sequential conformational changes and interdomain communications regulate tetramer formation via dimer. Our studies also show that overexpression of the mutants, defective in tetramer formation in Rep2a cells do not inhibit proliferation of hepatitis C virus, indicating critical role of a tetramer in the antiviral activity. Thus, the present study not only highlights the importance of hGBP1 tetramer in stimulated GMP formation, but also demonstrates its role in the antiviral activity against hepatitis C virus.

  12. Activation of Vago by interferon regulatory factor (IRF) suggests an interferon system-like antiviral mechanism in shrimp.

    Science.gov (United States)

    Li, Chaozheng; Li, Haoyang; Chen, Yixiao; Chen, Yonggui; Wang, Sheng; Weng, Shao-Ping; Xu, Xiaopeng; He, Jianguo

    2015-10-13

    There is a debate on whether invertebrates possess an antiviral immunity similar to the interferon (IFN) system of vertebrates. The Vago gene from arthropods encodes a viral-activated secreted peptide that restricts virus infection through activating the JAK-STAT pathway and is considered to be a cytokine functionally similar to IFN. In this study, the first crustacean IFN regulatory factor (IRF)-like gene was identified in Pacific white shrimp, Litopenaeus vannamei. The L. vannamei IRF showed similar protein nature to mammalian IRFs and could be activated during virus infection. As a transcriptional regulatory factor, L. vannamei IRF could activate the IFN-stimulated response element (ISRE)-containing promoter to regulate the expression of mammalian type I IFNs and initiate an antiviral state in mammalian cells. More importantly, IRF could bind the 5'-untranslated region of L. vannamei Vago4 gene and activate its transcription, suggesting that shrimp Vago may be induced in a similar manner to that of IFNs and supporting the opinion that Vago might function as an IFN-like molecule in invertebrates. These suggested that shrimp might possess an IRF-Vago-JAK/STAT regulatory axis, which is similar to the IRF-IFN-JAK/STAT axis of vertebrates, indicating that invertebrates might possess an IFN system-like antiviral mechanism.

  13. In Vitro Antiviral Activity of Rubia Cordifolia Aerial Part Extract Against Rotavirus

    Directory of Open Access Journals (Sweden)

    Yuanyuan Sun

    2016-09-01

    Full Text Available The root of Rubia cordifolia (R. cordifolia has been used traditionally as a hemostatic agent, while the aerial part of the plant consisting of leaf and stem is known to exhibit anti-diarrheal properties and has been widely used as a remedy in many parts of China. As rotavirus is one of the most commonly associated diarrhea-causing pathogen, this study aims to investigate the anti-rotaviral effect of R. cordifolia aerial part (RCAP. The cytotoxicity of RCAP towards MA-104 cells was evaluated using the WST-8 assay. Colloidal gold method and real time polymerase chain reaction (qPCR assay were used to confirm the findings of the antiviral assay. Then, 4',6-diamidino-2-phenylindole (DAPI staining method was subsequently used to investigate the mode of death among the cells. And the representative components of aqueous extract were isolated and identified. It was shown that both the viability of MA-104 cells and the viral load were reduced with increasing concentration of the extract. DAPI staining showed that virus-induced apoptosis was the cause of the low cell viability and viral load, an effect which was accelerated with incubation in the aqueous herbal extract. The major compounds postulated to exhibit this activity were isolated from the aqueous herbal extract and identified to be compounds Xanthopurpurin and Vanillic Acid. This study showed that RCAP extract effectively inhibited rotavirus multiplication by promoting virus-induced apoptosis in MA-104 cells.

  14. Preparation, characterization and in vitro antiviral activity evaluation of foscarnet-chitosan nanoparticles.

    Science.gov (United States)

    Russo, E; Gaglianone, N; Baldassari, S; Parodi, B; Cafaggi, S; Zibana, C; Donalisio, M; Cagno, V; Lembo, D; Caviglioli, G

    2014-06-01

    A new nanoparticulate system for foscarnet delivery was prepared and evaluated. Nanoparticles were obtained by ionotropic gelation of chitosan induced by foscarnet itself, acting as an ionotropic agent in a manner similar to tripolyphosphate anion. A Doehlert design allowed finding the suitable experimental conditions. Nanoparticles were between 200 and 300nm in diameter (around 450nm after redispersion). Nanoparticle size increased after 5h, but no size increase was observed after 48h when nanoparticles were crosslinked with glutaraldehyde. Zeta potential values of noncrosslinked and crosslinked nanoparticles were between 20 and 25mV, while drug loading of noncrosslinked nanoparticles was about 40% w/w (55% w/w for crosslinked nanoparticles). Nanoparticle yield was around 25% w/w. Crosslinked nanoparticles showed a controlled drug release. Foscarnet released from nanoparticles maintained the antiviral activity of the free drug when tested in vitro against lung fibroblasts (HELF) cells infected with HCMV strain AD-169. Moreover, nanoparticles showed no toxicity on non-infected HELF cells. These nanoparticles may represent a delivery system that could improve the therapeutic effect of foscarnet.

  15. In COS cells Vpu can both stabilize tetherin expression and counteract its antiviral activity.

    Science.gov (United States)

    Waheed, Abdul A; Kuruppu, Nishani D; Felton, Kathryn L; D'Souza, Darren; Freed, Eric O

    2014-01-01

    The interferon-inducible cellular protein tetherin (CD317/BST-2) inhibits the release of a broad range of enveloped viruses. The HIV-1 accessory protein Vpu enhances virus particle release by counteracting this host restriction factor. While the antagonism of human tetherin by Vpu has been associated with both proteasomal and lysosomal degradation, the link between Vpu-mediated tetherin degradation and the ability of Vpu to counteract the antiviral activity of tetherin remains poorly understood. Here, we show that human tetherin is expressed at low levels in African green monkey kidney (COS) cells. However, Vpu markedly increases tetherin expression in this cell line, apparently by sequestering it in an internal compartment that bears lysosomal markers. This stabilization of tetherin by Vpu requires the transmembrane sequence of human tetherin. Although Vpu stabilizes human tetherin in COS cells, it still counteracts the ability of tetherin to suppress virus release. The enhancement of virus release by Vpu in COS cells is associated with a modest reduction in cell-surface tetherin expression, even though the overall expression of tetherin is higher in the presence of Vpu. This study demonstrates that COS cells provide a model system in which Vpu-mediated enhancement of HIV-1 release is uncoupled from Vpu-mediated tetherin degradation.

  16. Atividade antiviral de extratos de plantas medicinais disponíveis comercialmente frente aos herpesvírus suíno e bovino Antiviral activity of commercially available medicinal plants on suid and bovine herpesviruses

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    V.M. Kaziyama

    2012-01-01

    Full Text Available O presente trabalho teve como objetivo pesquisar a atividade antiviral in vitro de plantas medicinais disponíveis comercialmente sobre herpesvírus suíno (SuHV-1 e bovino (BoHV-1. As espécies adquiridas foram Mikania glomerata, Cymbopogon citratus, Equisetum arvense, Peumus boldus, Solanum paniculatum, Malva sylvestris, Piper umbellatun e Solidago microglossa. A citotoxicidade dos extratos foi avaliada na linhagem celular MDBK pelas alterações morfológicas das células e obtenção da concentração máxima não citotóxica (CMNC de cada planta. A atividade antiviral foi realizada com os extratos em suas respectivas CMNC e avaliada com base na redução do título viral e expressos em porcentagem de inibição. Os extratos aquosos de Peumus boldus e Solanum paniculatum apresentaram atividade antiviral sobre o SuHV-1 com 98% de inibição viral enquanto o de Peumus boldus inibiu apenas o BoHV-1 em 99%.This paper aims to find commercially available medicinal plants showing antiviral activity in vitro on suid and bovine herpesviruses. The following species were tested: Mikania glomerata, Cymbopogon citratus, Equisetum arvense, Peumus boldus, Solanum paniculatum, Malva sylvestris, Piper umbellatun and Solidago microglossa. The cytotoxicity was evaluated by morphological changes in cells determining the maximum not cytotoxic concentration (MNCC. The antiviral activity was evaluated by viral title reduction. The extracts from Peumus boldus and Solanum paniculatum showed antiviral activity against SuHV-1 with 98% of inhibition. The extract of Peumus boldus also showed activity against BoHV-1 with 99% of inhibition.

  17. In-Vitro Antiviral Activities of Extracts of Plants of The Brazilian Cerrado against the Avian Metapneumovirus (aMPV

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    LK Kohn

    2015-09-01

    Full Text Available ABSTRACTAvian metapneumovirus (aMPV is a negative-sense single-stranded RNA enveloped virus of the Metapneumovirus genus belonging to theParamyxoviridae family. This virus may cause significant economic losses to the poultry industry, despite vaccination, which is the main tool for controlling and preventing aMPV. The aim of this study was to evaluate the antiviral activity of extracts of four different native plants of the Brazilian Cerrado against aMPV. The antiviral activity against aMPV was determined by titration. This technique measures the ability of plant extract dilutions (25 to 2.5 µg mL-1 to inhibit the cytopathic effect (CPE of the virus, expressed as inhibition percentage (IP. The maximum nontoxic concentration (MNTC of the extracts used in antiviral assay was 25 µg mL-1for Aspidosperma tomentosumand Gaylussacia brasiliensis, and 2.5 µg mL-1for Arrabidaea chicaand Virola sebifera. Twelve different extracts derived from four plant species collected from the Brazilian Cerrado were screened for antiviral activity against aMPV. G. brasiliensis, A. chica,and V. sebifera extracts presented inhibition rates of 99% in the early viral replication stages, suggesting that these extracts act during the adsorption phase. On the other hand, A. tomentosum inhibited 99% virus replication after the virus entered the cell. The biomonitored fractioning of extracts active against aMPV may be a tool to identify the active compounds of plant extracts and to determine their precise mode of action.

  18. Domain 2 of a Kazal serine proteinase inhibitor SPIPm2 from Penaeus monodon possesses antiviral activity against WSSV.

    Science.gov (United States)

    Visetnan, Suwattana; Donpudsa, Suchao; Supungul, Premruethai; Tassanakajon, Anchalee; Rimphanitchayakit, Vichien

    2014-12-01

    A 5-domain Kazal type serine proteinase inhibitor SPIPm2 from Penaeus monodon is involved in innate immune defense against white spot syndrome virus (WSSV). To test which domains were involved, the 5 domains of SPIPm2 were over-expressed and tested against WSSV infection. By using hemocyte primary cell culture treated with each recombinant SPIPm2 domain along with WSSV, the expression of WSSV early genes ie1, WSV477 and late gene VP28 were substantially reduced as compared to other domains when the recombinant domain 2, rSPIPm2D2, was used. Injecting the WSSV along with rSPIPm2D2 but not with other domains caused delay in mortality rate of the infected shrimp. The results indicate that the SPIPm2D2 possesses strong antiviral activity and, hence, contributes predominantly to the antiviral activity of SPIPm2.

  19. Muscovy duck reovirus infection rapidly activates host innate immune signaling and induces an effective antiviral immune response involving critical interferons.

    Science.gov (United States)

    Chen, Zhilong; Luo, Guifeng; Wang, Quanxi; Wang, Song; Chi, Xiaojuan; Huang, Yifan; Wei, Haitao; Wu, Baocheng; Huang, Shile; Chen, Ji-Long

    2015-02-25

    Muscovy duck reovirus (MDRV) is a highly pathogenic virus in waterfowl and causes significant economic loss in the poultry industry worldwide. Because the host innate immunity plays a key role in defending against virus invasion, more and more attentions have been paid to the immune response triggered by viral infection. Here we found that the genomic RNA of MDRV was able to rapidly induce the production of interferons (IFNs) in host. Mechanistically, MDRV infection induced robust expression of IFNs in host mainly through RIG-I, MDA5 and TLR3-dependent signaling pathways. In addition, we observed that silencing VISA expression in 293T cells could significantly inhibit the secretion of IFNs. Remarkably, the production of IFNs was reduced by inhibiting the activation of NF-κB or knocking down the expression of IRF-7. Furthermore, our study showed that treatment of 293T cells and Muscovy duck embryo fibroblasts with IFNs markedly impaired MDRV replication, suggesting that these IFNs play an important role in antiviral response during the MDRV infection. Importantly, we also detected the induced expression of RIG-I, MDA5, TLR3 and type I IFN in Muscovy ducks infected with MDRV at different time points post infection. The results from in vivo studies were consistent with those in 293T cells infected with MDRV. Taken together, our findings reveal that the host can resist MDRV invasion by activating innate immune response involving RIG-I, MDA5 and TLR3-dependent signaling pathways that govern IFN production.

  20. The differential antiviral activities of chicken interferon α (ChIFN-α and ChIFN-β are related to distinct interferon-stimulated gene expression.

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    Hongren Qu

    Full Text Available Chicken interferon α (ChIFN-α and ChIFN-β are type I IFNs that are important antiviral cytokines in the innate immune system. In the present study, we identified the virus-induced expression of ChIFN-α and ChIFN-β in chicken fibroblast DF-1 cells and systematically evaluated the antiviral activities of recombinant ChIFN-α and ChIFN-β by cytopathic-effect (CPE inhibition assays. We found that ChIFN-α exhibited stronger antiviral activity than ChIFN-β in terms of inhibiting the replication of vesicular stomatitis virus, Newcastle disease virus and avian influenza virus, respectively. To elucidate the mechanism of differential antiviral activities between the two ChIFNs, we measured the relative mRNA levels of IFN-stimulated genes (ISGs in IFN-treated DF-1 cells by real-time PCR. ChIFN-α displayed greater induction potency than ChIFN-β on several ISGs encoding antiviral proteins and MHC-I, whereas ChIFN-α was less potent than ChIFN-β for inducing ISGs involved in signaling pathways. In conclusion, ChIFN-α and ChIFN-β presented differential induction potency on various sets of ISGs, and the stronger antiviral activity of ChIFN-α is likely attributed to the greater expression levels of downstream antiviral ISGs.

  1. Evaluation of antiviral activities of Houttuynia cordata Thunb. extract, quercetin, quercetrin and cinanserin on murine coronavirus and dengue virus infection

    Institute of Scientific and Technical Information of China (English)

    K. H. Chiow; M. C. Phoon; Thomas Putti; Benny K. H. Tan; Vincent T. Chow

    2016-01-01

    Objective: To evaluate the in vitro activities of the ethyl acetate (EA) fraction of Houttuynia cordata (H. cordata) Thunb. (Saururaceae) and three of its constituent flavonoids (quercetin, quercitrin and rutin) against murine coronavirus and dengue virus (DENV). Methods: The antiviral activities of various concentrations of the EA fraction of H. cordata and flavonoids were assessed using virus neutralization tests against mouse hepatitis virus (MHV) and DENV type 2 (DENV-2). Cinanserin hydrochloride was also tested against MHV. The EA fraction of H. cordata was tested for acute oral toxicity in C57BL/6 mice. Results: The EA fraction of H. cordata inhibited viral infectivity up to 6 d. Cinanserin hydrochloride was able to inhibit MHV for only 2 d. The 50% inhibitory concentrations (IC50) of the EA fraction of H. cordata added before the viral adsorption stage were 0.98 μg/mL for MHV and 7.50 μg/mL for DENV-2 with absence of cytotoxicity. The mice fed with the EA fraction up to 2 000 mg/kg did not induce any signs of acute toxicity, with normal histological features of major organs. Certain flavonoids exhibited comparatively weaker antiviral activity, notably quercetin which could inhibit both MHV and DENV-2. This was followed by quercitrin which could inhibit DENV-2 but not MHV, whereas rutin did not exert any inhibitory effect on either virus. When quercetin was combined with quercitrin, enhancement of anti-DENV-2 activity and reduced cytotoxicity were observed. However, the synergistic efficacy of the flavonoid combination was still less than that of the EA fraction. Conclusions: The compounds in H. cordata contribute to the superior antiviral efficacy of the EA fraction which lacked cytotoxicity in vitro and acute toxicity in vivo. H. cordata has much potential for the development of antiviral agents against coronavirus and dengue infections.

  2. Skeletal modifications of [Formula: see text]-carboline alkaloids and their antiviral activity profile.

    Science.gov (United States)

    Yang, Yan; Huang, Yuanqiong; Song, Hongjian; Liu, Yuxiu; Wang, Lizhong; Wang, Qingmin

    2016-11-01

    To study the effect of the variation of fused ring size and substitution on the antiviral activity of [Formula: see text]-carboline alkaloids, four types of structurally novel [Formula: see text]-carboline alkaloids analogues, with indole-fused six- to nine-membered-rings motifs, were designed, synthesized, and evaluated for the inhibition of tobacco mosaic virus (TMV). Bioassay results indicated that most of these analogues had significant anti-TMV activity; especially I-14 (54 [Formula: see text] 3 % at 500 [Formula: see text]g/mL in vitro; 51 [Formula: see text] 2, 45 [Formula: see text] 2, and 42 [Formula: see text] 1 % at 500 [Formula: see text]g/mL in vivo), II-4 (53 [Formula: see text] 1 % at 500 [Formula: see text]g/mL in vitro; 49 [Formula: see text] 2, 57 [Formula: see text] 2, and 48 [Formula: see text] 1 % at 500 [Formula: see text]g/mL in vivo), and II-8 (48 [Formula: see text] 1 % at 500 [Formula: see text]g/mL in vitro; 53 [Formula: see text] 2 %, 56 [Formula: see text] 2 %, and 46 [Formula: see text] 1 % at 500 [Formula: see text]g/mL in vivo), which were more potent vs. TMV than was ribavirin (36 [Formula: see text] 1 % at 500 [Formula: see text]g/mL in vitro; 37 [Formula: see text] 2, 41 [Formula: see text] 2, and 38 [Formula: see text] 1 % at 500 [Formula: see text]g/mL in vivo). The size of the fused ring has important effects on anti-TMV potency, which may be ascribed to conformational differences. The X-ray structures of I-1, I-6, II-8, and III show differing conformational preferences. The most potent compounds can be used as leads for further optimization as antiphytoviral agents.

  3. IRAV (FLJ11286), an Interferon-Stimulated Gene with Antiviral Activity against Dengue Virus, Interacts with MOV10

    Science.gov (United States)

    Balinsky, Corey A.; Schmeisser, Hana; Wells, Alexandra I.; Ganesan, Sundar; Jin, Tengchuan; Singh, Kavita

    2016-01-01

    ABSTRACT Dengue virus (DENV) is a member of the genus Flavivirus and can cause severe febrile illness. Here, we show that FLJ11286, which we refer to as IRAV, is induced by DENV in an interferon-dependent manner, displays antiviral activity against DENV, and localizes to the DENV replication complex. IRAV is an RNA binding protein and localizes to cytoplasmic processing bodies (P bodies) in uninfected cells, where it interacts with the MOV10 RISC complex RNA helicase, suggesting a role for IRAV in the processing of viral RNA. After DENV infection, IRAV, along with MOV10 and Xrn1, localizes to the DENV replication complex and associates with DENV proteins. Depletion of IRAV or MOV10 results in an increase in viral RNA. These data serve to characterize an interferon-stimulated gene with antiviral activity against DENV, as well as to propose a mechanism of activity involving the processing of viral RNA. IMPORTANCE Dengue virus, a member of the family Flaviviridae, can result in a life-threatening illness and has a significant impact on global health. Dengue virus has been shown to be particularly sensitive to the effects of type I interferon; however, little is known about the mechanisms by which interferon-stimulated genes function to inhibit viral replication. A better understanding of the interferon-mediated antiviral response to dengue virus may aid in the development of novel therapeutics. Here, we examine the influence of the interferon-stimulated gene IRAV (FLJ11286) on dengue virus replication. We show that IRAV associates with P bodies in uninfected cells and with the dengue virus replication complex after infection. IRAV also interacts with MOV10, depletion of which is associated with increased viral replication. Our results provide insight into a newly identified antiviral gene, as well as broadening our understanding of the innate immune response to dengue virus infection. PMID:27974568

  4. The in vitro anti-viral potential of Setarud (IMOD™, a commercial herbal medicine with protective activity against acquired immune deficiency syndrome in clinical trials

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    Rezvan Zabihollahi

    2012-01-01

    Conclusions: Data from this study indicate that IMOD has significant anti-viral activity against HIV, HSV and MLV. Setarud could be subjected to further investigation after isolation of the constituents and determination of the toxic components.

  5. TLR9-dependent recognition of MCMV by IPC and DC generates coordinated cytokine responses that activate antiviral NK cell function.

    Science.gov (United States)

    Krug, Anne; French, Anthony R; Barchet, Winfried; Fischer, Jens A A; Dzionek, Andrzej; Pingel, Jeanette T; Orihuela, Michael M; Akira, Shizuo; Yokoyama, Wayne M; Colonna, Marco

    2004-07-01

    Natural interferon-producing cells (IPC) respond to viruses by secreting type I interferon (IFN) and interleukin-12 (IL-12). Toll-like receptor (TLR) 9 mediates IPC recognition of some of these viruses in vitro. However, whether TLR9-induced activation of IPC is necessary for an effective antiviral response in vivo is not clear. Here, we demonstrate that IPC and dendritic cells (DC) recognize murine cytomegalovirus (MCMV) through TLR9. TLR9-mediated cytokine secretion promotes viral clearance by NK cells that express the MCMV-specific receptor Ly49H. Although depletion of IPC leads to a drastic reduction of the IFN-alpha response, this allows other cell types to secrete IL-12, ensuring normal IFN-gamma and NK cell responses to MCMV. We conclude that the TLR9/MyD88 pathway mediates antiviral cytokine responses by IPC, DC, and possibly other cell types, which are coordinated to promote effective NK cell function and MCMV clearance.

  6. Nutritional and Chemical Composition and Antiviral Activity of Cultivated Seaweed Sargassum naozhouense Tseng et Lu 

    Directory of Open Access Journals (Sweden)

    Yonghong Liu

    2012-12-01

    Full Text Available Sargassum naozhouense is a brown seaweed used in folk medicine and applied for thousands of years in Zhanjiang, Guangdong province, China. This study is the first time to investigate its chemical composition and antiviral activity. On the dry weight basis, this seaweed was constituted of ca. 35.18% ash, 11.20% protein, 1.06% lipid and 47.73% total carbohydrate, and the main carbohydrate was water-soluble polysaccharide. The protein analysis indicated the presence of essential amino acids, which accounted for 36.35% of the protein. The most abundant fatty acids were C14:0, C16:0, C18:1 and C20:4. The ash fraction analysis indicated that essential minerals and trace elements, such as Fe, Zn and Cu, were present in the seaweed. IR analysis revealed that polysaccharides from cultivated S. naozhouense may be alginates and fucoidan. The polysaccharides possessed strong antiviral activity against HSV-1 in vitro with EC50 of 8.92 μg/mL. These results demonstrated cultivated S. naozhouense has a potential for its use in functional foods and antiviral new drugs.

  7. Three novel Anas platyrhynchos avian β-defensins, upregulated by duck hepatitis virus, with antibacterial and antiviral activities.

    Science.gov (United States)

    Ma, Deying; Lin, Lijuan; Zhang, Kexin; Han, Zongxi; Shao, Yuhao; Liu, Xiaoli; Liu, Shengwang

    2011-10-01

    Three novel Anas platyrhynchos avian β-defensins (Apl_AvBDs), Apl_AvBD4, 7 and 12, were identified successfully and characterized in tissues from Peking ducks in the present study. The cDNA fragment of Apl_AvBD4 contained 171 bp, and encoded 56 amino acids. The complete nucleotide sequences of Apl_AvBD7 and 12 contained 204 bp and 198 bp open reading frames, which encoded 67 and 65 amino acids, respectively. Both recombinant and synthetic forms of the three Apl_AvBDs showed antibacterial activity against most of the bacteria investigated, including Gram-negative and Gram-positive bacteria, except for Salmonella choleraesuis. In addition, the antibacterial activity of all the three Apl_AvBDs decreased significantly in 150 mM NaCl. Significant antiviral activity of the three Apl_AvBDs was shown against duck hepatitis virus (DHV). However, none of the Apl_AvBDs showed significant hemolytic activity. Additionally, the expressions of the three Apl_AvBDs in response to DHV infection was highly variable, and significant upregulation of Apl_AvBD7 in liver was found in response to infection at different time points. Expression of Apl_AvBD4 in thymus, and of Apl_AvBD7 in bone marrow was induced in a time-dependent fashion by DHV infection. In contrast, expression of Apl_AvBD12 was found to be significantly decreased, and was hard to detect in cecal tonsil, spleen, bursa of Fabricius, and thymus of ducks at some time points after DHV infection. The present results demonstrate that Apl_AvBDs play vital roles in the immune response of ducks against bacterial and viral pathogens.

  8. Antiviral Activity of a Nanoemulsion of Polyprenols from Ginkgo Leaves against Influenza A H3N2 and Hepatitis B Virus in Vitro

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    Cheng-Zhang Wang

    2015-03-01

    Full Text Available In order to improve the bioavailability levels of polyprenols (derived from ginkgo leaves (GBP in the human body, a GBP nanoemulsion was prepared, and its antiviral activity was evaluated against influenza A H3N2 and hepatitis B virus in vitro. Methods: A GBP nanoemulsion was prepared by inversed-phase emulsification (IPE. Next, we investigated the antiviral activity of the GBP nanoemulsion on influenza A H3N2 and hepatitis B virus in vitro by the MTT (3-(4,5-dimethylthiazol-2-yl-2,5-diphenlytetrezolium bromide method. ELISA and the fluorescent quantitative PCR method were used to measure the content of HBsAg, HBeAg and DNA virus in human samples. Results: The GBP nanoemulsion exhibited uniformity at an average particle size 97 nm with a hydrophilic-lipophilic balance (HLB of 9.5. GBP is non-toxic to normal cells, hepatitis B virus DNA, hepatitis B virus antigen and HepG2215. Furthermore, GBP could reach a 70% virucidal activity and a 74.9% protection rate (*** p < 0.001 on MDCK cells infected with H3N2 virus at a high concentration of 100 μg/mL. GBP had a good inhibition rate on HBsAg (52.11%, ** p < 0.01 at 50 μg/mL and Day 9 of incubation, and a 67.32% inhibition effect on HBeAg at a high concentration of 100 μg/mL and Day 9. GBP had good inhibition on HBV DNA with CT 18.6 and lower copies (** p < 0.01 at a middle concentration of 12.5 to 25 μg/mL. Conclusions: The GBP nanoemulsion was very stable and non-toxic and had very strong antiviral activity against influenza A H3N2 and hepatitis B virus in vitro. The inhibitory effects and reactive mechanisms were similar to the drug, 3TC; by lengthening the incubation time and increasing the drug concentration, GBP has promising potential as an antiviral drug.

  9. ASK1 restores the antiviral activity of APOBEC3G by disrupting HIV-1 Vif-mediated counteraction.

    Science.gov (United States)

    Miyakawa, Kei; Matsunaga, Satoko; Kanou, Kazuhiko; Matsuzawa, Atsushi; Morishita, Ryo; Kudoh, Ayumi; Shindo, Keisuke; Yokoyama, Masaru; Sato, Hironori; Kimura, Hirokazu; Tamura, Tomohiko; Yamamoto, Naoki; Ichijo, Hidenori; Takaori-Kondo, Akifumi; Ryo, Akihide

    2015-04-22

    APOBEC3G (A3G) is an innate antiviral restriction factor that strongly inhibits the replication of human immunodeficiency virus type 1 (HIV-1). An HIV-1 accessory protein, Vif, hijacks the host ubiquitin-proteasome system to execute A3G degradation. Identification of the host pathways that obstruct the action of Vif could provide a new strategy for blocking viral replication. We demonstrate here that the host protein ASK1 (apoptosis signal-regulating kinase 1) interferes with the counteraction by Vif and revitalizes A3G-mediated viral restriction. ASK1 binds the BC-box of Vif, thereby disrupting the assembly of the Vif-ubiquitin ligase complex. Consequently, ASK1 stabilizes A3G and promotes its incorporation into viral particles, ultimately reducing viral infectivity. Furthermore, treatment with the antiretroviral drug AZT (zidovudine) induces ASK1 expression and restores the antiviral activity of A3G in HIV-1-infected cells. This study thus demonstrates a distinct function of ASK1 in restoring the host antiviral system that can be enhanced by AZT treatment.

  10. The cytoplasmic location of chicken mx is not the determining factor for its lack of antiviral activity.

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    Camilla T O Benfield

    Full Text Available BACKGROUND: Chicken Mx belongs to the Mx family of interferon-induced dynamin-like GTPases, which in some species possess potent antiviral properties. Conflicting data exist for the antiviral capability of chicken Mx. Reports of anti-influenza activity of alleles encoding an Asn631 polymorphism have not been supported by subsequent studies. The normal cytoplasmic localisation of chicken Mx may influence its antiviral capacity. Here we report further studies to determine the antiviral potential of chicken Mx against Newcastle disease virus (NDV, an economically important cytoplasmic RNA virus of chickens, and Thogoto virus, an orthomyxovirus known to be exquisitely sensitive to the cytoplasmic MxA protein from humans. We also report the consequences of re-locating chicken Mx to the nucleus. METHODOLOGY/PRINCIPAL FINDINGS: Chicken Mx was tested in virus infection assays using NDV. Neither the Asn631 nor Ser631 Mx alleles (when transfected into 293T cells showed inhibition of virus-directed gene expression when the cells were subsequently infected with NDV. Human MxA however did show significant inhibition of NDV-directed gene expression. Chicken Mx failed to inhibit a Thogoto virus (THOV minireplicon system in which the cytoplasmic human MxA protein showed potent and specific inhibition. Relocalisation of chicken Mx to the nucleus was achieved by inserting the Simian Virus 40 large T antigen nuclear localisation sequence (SV40 NLS at the N-terminus of chicken Mx. Nuclear re-localised chicken Mx did not inhibit influenza (A/PR/8/34 gene expression during virus infection in cell culture or influenza polymerase activity in A/PR/8/34 or A/Turkey/50-92/91 minireplicon systems. CONCLUSIONS/SIGNIFICANCE: The chicken Mx protein (Asn631 lacks inhibitory effects against THOV and NDV, and is unable to suppress influenza replication when artificially re-localised to the cell nucleus. Thus, the natural cytoplasmic localisation of the chicken Mx protein does

  11. Oncostatin M Enhances the Antiviral Effects of Type I Interferon and Activates Immunostimulatory Functions in Liver Epithelial Cells▿

    Science.gov (United States)

    Larrea, Esther; Aldabe, Rafael; Gonzalez, Iranzu; Segura, Victor; Sarobe, Pablo; Echeverria, Itziar; Prieto, Jesus

    2009-01-01

    Oncostatin M (OSM) is released together with type I interferon (IFN) by activated dendritic cells, suggesting a concerted action of these cytokines in the biological response against infection. We found that OSM increases the antiviral effect of IFN-α in Huh7 hepatoma cells infected with hepatitis A or hepatitis C virus and synergizes with IFN-α in the induction of antiviral genes. The combination of OSM and IFN-α led to upregulation of both STAT1 and STAT3 together with intense and prolonged activation of STAT1, STAT3, and Jak1. OSM with or without IFN-α also activated p38 mitogen-activated protein kinase, which is known to enhance transcription of IFN-α-inducible genes. Interestingly, OSM combined with IFN-α strongly induced immunoproteasome genes and other genes involved in antigen processing and presentation. Moreover, OSM, alone or in combination with IFN-α, upregulated relevant innate immunity molecules and increased the expression of intracellular adhesion molecule 1 and interleukin-15 receptor alpha (IL-15Rα) in liver cells. Hepatoma cells transfected with a plasmid encoding a viral antigen were able to activate effector T cells when pretreated with IFN-α plus OSM but not with each cytokine separately. Also, OSM, more than IFN-α, augmented the ability of Huh7 cells to transpresent IL-15 to responding lymphocytes and increased the immunostimulatory activity of liver epithelial cells by presenting a short viral peptide to sensitized cytotoxic T cells. In conclusion, OSM enhances the antiviral effects of type I interferon and cooperates with it in the induction of adaptive immune responses to pathogens. These findings may have therapeutic implications. PMID:19158240

  12. Broad-spectrum antiviral agents

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    Jun-Da eZhu

    2015-05-01

    Full Text Available Development of highly effective, broad-spectrum antiviral agents is the major objective shared by the fields of virology and pharmaceutics. Antiviral drug development has focused on targeting viral entry and replication, as well as modulating cellular defense system. High throughput screening of molecules, genetic engineering of peptides, and functional screening of agents have identified promising candidates for development of optimal broad-spectrum antiviral agents to intervene in viral infection and control viral epidemics. This review discusses current knowledge, prospective applications, opportunities, and challenges in the development of broad-spectrum antiviral agents.

  13. Mixture toxicity of the antiviral drug Tamiflu (oseltamivir ethylester) and its active metabolite oseltamivir acid

    Energy Technology Data Exchange (ETDEWEB)

    Escher, Beate I., E-mail: b.escher@uq.edu.au [University of Queensland, National Research Centre for Environmental Toxicology (Entox), 39 Kessels Rd, Brisbane, Qld 4108 (Australia); Eawag, Swiss Federal Institute of Aquatic Science and Technology, 8600 Duebendorf (Switzerland); Bramaz, Nadine; Lienert, Judit; Neuwoehner, Judith [Eawag, Swiss Federal Institute of Aquatic Science and Technology, 8600 Duebendorf (Switzerland); Straub, Juerg Oliver [F.Hoffmann-La Roche Ltd, Corporate Safety, Health and Environmental Protection, 4070 Basel (Switzerland)

    2010-02-18

    Tamiflu (oseltamivir ethylester) is an antiviral agent for the treatment of influenza A and B. The pro-drug Tamiflu is converted in the human body to the pharmacologically active metabolite, oseltamivir acid, with a yield of 75%. Oseltamivir acid is indirectly photodegradable and slowly biodegradable in sewage works and sediment/water systems. A previous environmental risk assessment has concluded that there is no bioaccumulation potential of either of the compounds. However, little was known about the ecotoxicity of the metabolite. Ester hydrolysis typically reduces the hydrophobicity and thus the toxicity of a compound. In this case, a zwitterionic, but overall neutral species is formed from the charged parent compound. If the speciation and predicted partitioning into biological membranes is considered, the metabolite may have a relevant contribution to the overall toxicity. These theoretical considerations triggered a study to investigate the toxicity of oseltamivir acid (OA), alone and in binary mixtures with its parent compound oseltamivir ethylester (OE). OE and OA were found to be baseline toxicants in the bioluminescence inhibition test with Vibrio fischeri. Their mixture effect lay between predictions for concentration addition and independent action for the mixture ratio excreted in urine and nine additional mixture ratios of OE and OA. In contrast, OE was an order of magnitude more toxic than OA towards algae, with a more pronounced effect when the direct inhibition of photosystem II was used as toxicity endpoint opposed to the 24 h growth rate endpoint. The binary mixtures in this assay yielded experimental mixture effects that agreed with predictions for independent action. This is consistent with the finding that OE exhibits slightly enhanced toxicity, while OA acts as baseline toxicant. Therefore, with respect to mixture classification, the two compounds can be considered as acting according to different modes of toxic action, although there are

  14. Phosphoramidate derivatives of acyclovir: synthesis and antiviral activity in HIV-1 and HSV-1 models in vitro.

    Science.gov (United States)

    Zakirova, Natalia F; Shipitsyn, Alexander V; Jasko, Maxim V; Prokofjeva, Maria M; Andronova, Valeria L; Galegov, Georgiy A; Prassolov, Vladimir S; Kochetkov, Sergey N

    2012-10-01

    The antiviral activity against HIV and HSV and the chemical stability of ACV phosphoramidate derivatives were studied. The phosphoramidates of ACV demonstrated moderate activity. The best compound appeared to be 9-(2-hydroxymethyl)guanine phosphoromonomorpholidate (7), which inhibited virus replication in pseudo-HIV-1 particles by 50% at 50 μM. It also inhibited replication of wild-type HSV-1 (9.7 μM) as well as an acyclovir-resistant strain (25 μM). None of the synthesised compounds showed any cytotoxicity.

  15. Purification of Houttuynia cordata Thunb. Essential Oil Using Macroporous Resin Followed by Microemulsion Encapsulation to Improve Its Safety and Antiviral Activity.

    Science.gov (United States)

    Pang, Jianmei; Dong, Wujun; Li, Yuhuan; Xia, Xuejun; Liu, Zhihua; Hao, Huazhen; Jiang, Lingmin; Liu, Yuling

    2017-02-15

    Essential oil extracted from Houttuynia cordata Thunb. (H. cordata) is widely used in traditional Chinese medicine due to its excellent biological activities. However, impurities and deficient preparations of the essential oil limit its safety and effectiveness. Herein, we proposed a strategy to prepare H. cordata essential oil (HEO) safely and effectively by combining the solvent extraction and the macroporous resin purification flexibly, and then encapsulating it using microemulsion. The extraction and purification process were optimized by orthogonal experimental design and adsorption-desorption tests, respectively. The average houttuynin content in pure HEO was then validated at 44.3% ± 2.01%, which presented a great potential for industrial application. Subsequently, pure HEO-loaded microemulsion was prepared by high-pressure homogenization and was then fully characterized. Results showed that the pure HEO-loaded microemulsion was successfully prepared with an average particle size of 179.1 nm and a high encapsulation rate of 94.7%. Furthermore, safety evaluation tests and in vitro antiviral testing indicated that the safety and activity of HEO were significantly improved after purification using D101 resin and were further improved by microemulsion encapsulation. These results demonstrated that the purification of HEO by macroporous resin followed by microemulsion encapsulation would be a promising approach for industrial application of HEO for the antiviral therapies.

  16. Antiviral activity of plant extract from Tanacetum vulgare against Cucumber Mosaic Virus and Potato Virus Y

    Directory of Open Access Journals (Sweden)

    Nikolay Petrov

    2016-09-01

    Full Text Available Cucumber mosaic virus (CMV and Potato virus Y (PVY have been described among the top five important viruses infecting vegetable species worldwide. They cause severe damages in fruits and cultivated plants. There is currently no available effective pesticide to control these viral diseases. Higher plants contain a wide spectrum of secondary metabolites such as phenolics, flavonoids, quinones, tannins, essential oils, alkaloids, saponins, sterols and others. Extracts prepared from different plants have been reported to have a variety of properties including antifungal, antiviral and antibacterial properties against pathogens. Tanacetum vulgare (Tansy is native to Europe, Asia, and North Africa. It has many horticultural and pharmacological qualities. T. vulgare is principally used in traditional Asian and North African medicine as an antihelminthic, antispasmodic, stimulant to abdominal viscera, tonic, antidiabetic and diuretic, and it is antihypertensive. In our research we established antiviral effect of methanol extract from T. vulgare against CMV and PVY in tomato plants.

  17. The olive leaf extract exhibits antiviral activity against viral haemorrhagic septicaemia rhabdovirus (VHSV).

    Science.gov (United States)

    Micol, Vicente; Caturla, Nuria; Pérez-Fons, Laura; Más, Vicente; Pérez, Luis; Estepa, Amparo

    2005-06-01

    A commercial plant extract derived from olive tree leaf (Olea europaea) (LExt) and its major compound, oleuropein (Ole), inhibited the in vitro infectivity of the viral haemorrhagic septicaemia virus (VHSV), a salmonid rhabdovirus. Incubation of virus with LExt or Ole before infection reduced the viral infectivity to 10 and 30%, respectively. Furthermore, LExt drastically decreased VHSV titers and viral protein accumulation (virucidal effect) in a dose dependent manner when added to cell monolayers 36 h post-infection. On the other hand, both the LExt and Ole were able to inhibit cell-to-cell membrane fusion induced by VHSV in uninfected cells, suggesting interactions with viral envelope. Therefore, we propose that O. europaea could be used as a potential source of promising natural antivirals, which have demonstrated to lack impact on health and environment. In addition, Ole could be used to design other related antiviral agents.

  18. Antiviral activity of Basidiomycete mycelia against influenza type A(serotype H1N1) and herpes simplex virus type 2 in cell culture

    Institute of Scientific and Technical Information of China (English)

    Tetiana; Krupodorova; Svetlana; Rybalko; Victor; Barshteyn

    2014-01-01

    In this study, we investigated the in vitro antiviral activity of the mycelia of higher mushrooms against influenza virus type A(serotype H1N1) and herpes simplex virus type 2(HSV-2), strain BH. All 10 investigated mushroom species inhibited the reproduction of influenza virus strain A/FM/1/47(H1N1) in MDCK cells reducing the infectious titer by 2.0–6.0 lg ID50. Four species, Pleurotus ostreatus, Fomes fomentarius, Auriporia aurea, and Trametes versicolor, were also determined to be effective against HSV-2 strain BH in RK-13 cells, with similar levels of inhibition as for influenza. For some of the investigated mushroom species—Pleurotus eryngii, Lyophyllum shimeji, and Flammulina velutipes—this is the first report of an anti-influenza effect. This study also reports the first data on the medicinal properties of A. aurea, including anti-influenza and antiherpetic activities. T. versicolor 353 mycelium was found to have a high therapeutic index(324.67), and may be a promising material for the pharmaceutical industry as an anti-influenza and antiherpetic agent with low toxicity. Mycelia with antiviral activity were obtained in our investigation by bioconversion of agricultural wastes(amaranth flour after CO2 extraction), which would reduce the cost of the final product and solve some ecological problems.

  19. Antiviral activity of Basidiomycete mycelia against influenza type A (serotype H1N1) and herpes simplex virus type 2 in cell culture.

    Science.gov (United States)

    Krupodorova, Tetiana; Rybalko, Svetlana; Barshteyn, Victor

    2014-10-01

    In this study, we investigated the in vitro antiviral activity of the mycelia of higher mushrooms against influenza virus type A (serotype H1N1) and herpes simplex virus type 2 (HSV-2), strain BH. All 10 investigated mushroom species inhibited the reproduction of influenza virus strain A/FM/1/47 (H1N1) in MDCK cells reducing the infectious titer by 2.0-6.0 lg ID50. Four species, Pleurotus ostreatus, Fomes fomentarius, Auriporia aurea, and Trametes versicolor, were also determined to be effective against HSV-2 strain BH in RK-13 cells, with similar levels of inhibition as for influenza. For some of the investigated mushroom species-Pleurotus eryngii, Lyophyllum shimeji, and Flammulina velutipes-this is the first report of an anti-influenza effect. This study also reports the first data on the medicinal properties of A. aurea, including anti-influenza and antiherpetic activities. T. versicolor 353 mycelium was found to have a high therapeutic index (324.67), and may be a promising material for the pharmaceutical industry as an anti-influenza and antiherpetic agent with low toxicity. Mycelia with antiviral activity were obtained in our investigation by bioconversion of agricultural wastes (amaranth flour after CO2 extraction), which would reduce the cost of the final product and solve some ecological problems.

  20. Partial antiviral activities detection of chicken Mx jointing with neuraminidase gene (NA against Newcastle disease virus.

    Directory of Open Access Journals (Sweden)

    Yani Zhang

    Full Text Available As an attempt to increase the resistance to Newcastle Disease Virus (NDV and so further reduction of its risk on the poultry industry. This work aimed to build the eukaryotic gene co-expression plasmid of neuraminidase (NA gene and myxo-virus resistance (Mx and detect the gene expression in transfected mouse fibroblasts (NIH-3T3 cells, it is most important to investigate the influence of the recombinant plasmid on the chicken embryonic fibroblasts (CEF cells. cDNA fragment of NA and mutant Mx gene were derived from pcDNA3.0-NA and pcDNA3.0-Mx plasmid via PCR, respectively, then NA and Mx cDNA fragment were inserted into the multiple cloning sites of pVITRO2 to generate the eukaryotic co-expression plasmid pVITRO2-Mx-NA. The recombinant plasmid was confirmed by restriction endonuclease treatment and sequencing, and it was transfected into the mouse fibroblasts (NIH-3T3 cells. The expression of genes in pVITRO2-Mx-NA were measured by RT-PCR and indirect immunofluorescence assay (IFA. The recombinant plasmid was transfected into CEF cells then RT-PCR and the micro-cell inhibition tests were used to test the antiviral activity for NDV. Our results showed that co-expression vector pVITRO2-Mx-NA was constructed successfully; the expression of Mx and NA could be detected in both NIH-3T3 and CEF cells. The recombinant proteins of Mx and NA protect CEF cells from NDV infection until after 72 h of incubation but the individually mutagenic Mx protein or NA protein protects CEF cells from NDV infection till 48 h post-infection, and co-transfection group decreased significantly NDV infection compared with single-gene transfection group (P<0. 05, indicating that Mx-NA jointing contributed to delaying the infection of NDV in single-cell level and the co-transfection of the jointed genes was more powerful than single one due to their synergistic effects.

  1. Evaluation of the antiviral activity of a green tea solution as a hand-wash disinfectant.

    Science.gov (United States)

    Shin, Woo-Jin; Kim, Young-Kyung; Lee, Kwang-Hee; Seong, Baik-Lin

    2012-01-01

    Based on the broad-spectrum antiviral effect of green tea catechins, we established an experimental skin contact model for influenza virus transmission and evaluated the use of a green tea solution as a first-hand disinfectant. The infectivity of the virus on the skin cell layer became obsolete when washed with the green tea solution. The skin contact model could be applied to develop non-pharmaceutical intervention measures for reducing human transmission of the influenza virus.

  2. Antiviral Activity of a Small-Molecule Inhibitor of Filovirus Infection

    Science.gov (United States)

    2010-05-01

    virus ) causes Marburg hemorrhagic fever (MHF) among hu- mans and nonhuman primates. Case fatality rates of up to 90% have been reported for outbreaks...infected mice. Antiviral Res. 55:151–159. 6. Centers for Disease Control and Prevention. 2005. Outbreak of Marburg virus hemorrhagic fever—Angola...Interaction of Tsg101 with Marburg virus VP40 depends on the PPPY motif, but not the PT/SAP motif as in the case of Ebola virus , and Tsg101 plays a

  3. Postcoital bioavailability and antiviral activity of 0.5% PRO 2000 gel: implications for future microbicide clinical trials.

    Directory of Open Access Journals (Sweden)

    Marla J Keller

    Full Text Available BACKGROUND: The pharmacokinetics and pharmacodynamics of vaginal microbicides are typically assessed among sexually abstinent women. However, the physical act of sex may modulate gel distribution, and preclinical studies demonstrate seminal plasma interferes with the antiviral activity of several microbicides. This study compared the biological activity and concentration of PRO 2000 in cervicovaginal lavage (CVL collected in the absence or following coitus. METHODS: CVL samples were collected from ten heterosexual couples at baseline, after sex, after a single dose of 0.5% PRO 2000 gel and sex, and after gel application without sex. The impact of CVL on HIV-1 infection of TZM-bl cells and HSV-2 infection of CaSki cells was monitored by luciferase and plaque assay, respectively. PRO 2000 concentrations were measured by fluorescence. RESULTS: CVL collected after PRO 2000 application significantly inhibited HIV-1 and HSV-2 (p = 0.01. However, the antiviral activity was reduced following sex and no significant protective effect was observed in postcoital CVL obtained in the presence compared to the absence of PRO 2000 for HIV (p = 0.45 or HSV-2 (p = 0.56. Less PRO 2000 was recovered in postcoital CVL, which, in conjunction with interference by seminal plasma, may have contributed to lower antiviral activity. CONCLUSIONS: Postcoital responses to PRO 2000 differ from precoital measures and the results obtained may provide insights into the clinical trial findings in which there was no significant protection against HIV-1 or HSV-2. Postcoital studies should be incorporated into clinical studies before embarking on large-scale efficacy trials.

  4. Antagonist peptides of human interferon-α2b isolated from phage display library inhibit interferon induced antiviral activity

    Institute of Scientific and Technical Information of China (English)

    Wang TIAN; Gang BAI; Zheng-he LI; Wen-bo YANG

    2006-01-01

    Aim: To screen human interferon (IFN)-α2b antagonist peptides from a phage displayed heptapeptide library. Methods: WISH cells and polyclonal anti-IFN-α2b antibodies were used to select IFN receptor-binding peptides from a phage displayed heptapeptide library. The specific binding of phage clones was examined by phage ELISA and immunohistochemistry. The specific binding activities of synthetic peptides to WISH cells were detected by competition assay. Effects of synthetic peptides to IFN-induced antiviral activity were analyzed by evaluating the cytopathic effect (CPE) using the MTT method. Results: Twenty-three positive clones were obtained after seven rounds of selection. Ten clones were randomly picked from the positive clones and were sequenced. The corresponding amino acid sequences suggested 3 groups homologous to the 3 domains of IFN-α2b, defined by residues 24-41, 43-49, and 148-158 of IFN-α2b. As they presented as corresponding to IFN receptor-binding domains, AB loop and E helix, clone № 26 and 35 were chosen for further characterization and shown to bind to WISH cells. Two peptides corresponding to clone № 26 and 35, designated SP-7(SLSPGLP) and FY-7(FSAPVRY) were shown to compete with GFP-IFN-α2b for binding to its receptor and to inhibit the IFN-α2b-induced antiviral activity. Conclusion: Both IFN-α2b antagonist peptides, SP-7 and FY-7, were able to inhibit the IFN-induced antiviral activity, and could be helpful in laying the foundation for the molecular mechanism of the interaction between IFN and its receptor.

  5. Convergent Transcription of Interferon-stimulated Genes by TNF-α and IFN-α Augments Antiviral Activity against HCV and HEV

    Science.gov (United States)

    Wang, Wenshi; Xu, Lei; Brandsma, Johannes H.; Wang, Yijin; Hakim, Mohamad S.; Zhou, Xinying; Yin, Yuebang; Fuhler, Gwenny M.; van der Laan, Luc J. W.; van der Woude, C. Janneke; Sprengers, Dave; Metselaar, Herold J.; Smits, Ron; Poot, Raymond A.; Peppelenbosch, Maikel P.; Pan, Qiuwei

    2016-01-01

    IFN-α has been used for decades to treat chronic hepatitis B and C, and as an off-label treatment for some cases of hepatitis E virus (HEV) infection. TNF-α is another important cytokine involved in inflammatory disease, which can interact with interferon signaling. Because interferon-stimulated genes (ISGs) are the ultimate antiviral effectors of the interferon signaling, this study aimed to understand the regulation of ISG transcription and the antiviral activity by IFN-α and TNF-α. In this study, treatment of TNF-α inhibited replication of HCV by 71 ± 2.4% and HEV by 41 ± 4.9%. Interestingly, TNF-α induced the expression of a panel of antiviral ISGs (2-11 fold). Blocking the TNF-α signaling by Humira abrogated ISG induction and its antiviral activity. Chip-seq data analysis and mutagenesis assay further revealed that the NF-κB protein complex, a key downstream element of TNF-α signaling, directly binds to the ISRE motif in the ISG promoters and thereby drives their transcription. This process is independent of interferons and JAK-STAT cascade. Importantly, when combined with IFN-α, TNF-α works cooperatively on ISG induction, explaining their additive antiviral effects. Thus, our study reveals a novel mechanism of convergent transcription of ISGs by TNF-α and IFN-α, which augments their antiviral activity against HCV and HEV. PMID:27150018

  6. High Expression of Antiviral and Vitamin D Pathway Genes Are a Natural Characteristic of a Small Cohort of HIV-1-Exposed Seronegative Individuals

    Science.gov (United States)

    Aguilar-Jimenez, Wbeimar; Saulle, Irma; Trabattoni, Daria; Vichi, Francesca; Lo Caputo, Sergio; Mazzotta, Francesco; Rugeles, Maria T.; Clerici, Mario; Biasin, Mara

    2017-01-01

    Natural resistance to HIV-1 infection is influenced by genetics, viral-exposure, and endogenous immunomodulators such as vitamin D (VitD), being a multifactorial phenomenon that characterizes HIV-1-exposed seronegative individuals (HESNs). We compared mRNA expression of 10 antivirals, 5 immunoregulators, and 3 VitD pathway genes by qRT-PCR in cells of a small cohort of 11 HESNs, 16 healthy-controls (HCs), and 11 seropositives (SPs) at baseline, in response to calcidiol (VitD precursor) and/or aldithriol-2-(AT2)-inactivated HIV-1. In addition, the expression of TIM-3 on T and NK cells of six HCs after calcidiol and calcitriol (active VitD) treatments was evaluated by flow cytometry. Calcidiol increased the mRNA expression of HAVCR2 (TIM-3; Th1-cells inhibitor) in HCs and HESNs. AT2-HIV-1 increased the mRNA expression of the activating VitD enzyme CYP27B1, of the endogenous antiviral proteins MX2, TRIM22, APOBEC3G, and of immunoregulators ERAP2 and HAVCR2, but reduced the mRNA expression of VitD receptor (VDR) and antiviral peptides PI3 and CAMP in all groups. Remarkably, higher mRNA levels of VDR, CYP27B1, PI3, CAMP, SLPI, and of ERAP2 were found in HESNs compared to HCs either at baseline or after stimuli. Furthermore, calcitriol increases the percentage of CD4+ T cells expressing TIM-3 protein compared to EtOH controls. These results suggest that high mRNA expression of antiviral and VitD pathway genes could be genetically determined in HESNs more than viral-induced at least in peripheral blood mononuclear cells. Moreover, the virus could potentiate bio-activation and use of VitD, maintaining the homeostasis of the immune system. Interestingly, VitD-induced TIM-3 on T cells, a T cell inhibitory and anti-HIV-1 molecule, requires further studies to analyze the functional outcomes during HIV-1 infection. PMID:28243241

  7. In vitro antiviral activity of some novel isatin derivatives against HCV and SARS-CoV viruses

    Directory of Open Access Journals (Sweden)

    Selvam P

    2008-01-01

    Full Text Available 4-[(1,2-dihydro-2-oxo-3H-indol-3-ylideneamino]-N(4,6-dimethyl-2-pyrimidinybenzene sulphonamide and its derivatives were evaluated for antiviral activity against Pathogenic viruses such as Hepatitis C Virus and SARS-CoV in Vero and Huh 5-2 cells, respectively. The 5-fluoro derivative inhibited the HCV RNA synthesis at 6 µg/ml, without toxicity at a concentration up to 42 µg/ml in Huh 5-2 cells. Among the compounds tested SPIII-5F exhibits the 45% maximum protection against replication of SARS-CoV in Vero cells.

  8. Antiviral activity of seven iridoids, three saikosaponins and one phenylpropanoid glycoside extracted from Bupleurum rigidum and Scrophularia scorodonia.

    Science.gov (United States)

    Bermejo, Paulina; Abad, María José; Díaz, Ana María; Fernández, Lidia; De Santos, Javier; Sanchez, Sandra; Villaescusa, Lucinda; Carrasco, Luis; Irurzun, Alicia

    2002-02-01

    As part of our screening of antiviral agents from medicinal plants, 11 compounds from plant origin (Bupleurum rigidum and Scrophularia scorodonia), three saikosaponins, seven iridoids and one phenylpropanoid glycoside were tested in vitro against herpes simplex type I (HSV-1), vesicular stomatitis virus (VSV) and poliovirus type 1. Five of these compounds showed antiviral activity against VSV. The percentages of cellular viability at the non-toxic limit concentrations of the active compounds were: verbascoside 53.6 % at 500 microg/ml, 8-acetylharpagide 32.1 % at 500 microg/ml, harpagoside 43.3 % at 450 microg/ml, scorodioside 47.8 % at 500 microg/ml and buddlejasaponin IV 56.9 % at 25 microg/ml. Although none of the saikosaponins were active against HSV-1, the iridoid scorodioside showed moderate in vitro anti-HSV-1 activity (30.6 % at 500 microg/ml). However, none of the compounds tested in this survey had any effect against poliovirus.

  9. A randomized, placebo controlled, double masked phase IB study evaluating the safety and antiviral activity of aprepitant, a neurokinin-1 receptor antagonist in HIV-1 infected adults.

    Directory of Open Access Journals (Sweden)

    Pablo Tebas

    Full Text Available BACKGROUND: Neurokinin-1 receptor (NK1R antagonists have anti-HIV activity in monocyte-derived macrophages, decrease CCR5 expression and improve natural killer cell function ex vivo. Aprepitant is a NK1R antagonist approved by FDA as an antiemetic. METHODS: We conducted a phase IB randomized, placebo controlled, double masked study to evaluate the safety, antiviral activity, pharmacokinetics and immune-modulatory effects of aprepitant in HIV-infected adults not receiving antiretroviral therapy, with CD4+ cell count ≥350 cells/mm(3 and plasma viral load ≥2,000 copies/ml. Subjects were stratified by viral load (< vs. ≥20,000 copies/ml and randomized within each stratum to receive aprepitant at 125 mg QD(Low, or 250 mg QD(High, or placebo(PL for 14 days, and followed for 42 days. RESULTS: Thirty subjects were randomized and 27 completed treatment (9, 8, 10 subjects in 125 (Low, 250 (High, and PL groups. 63% were male; 37% white; mean (SD age 43 (9.3 years. Geometric mean baseline viral load (copies/ml for Low, High, and PL was 15,709, 33,013, and 19,450, respectively. Mean (95%CI change in log10 viral load at day 14 for Low, High, and PL was -0.02(-0.24,+0.20, -0.05(-0.21,+0.10, and +0.04(-0.08,+0.16, respectively. The number of subjects with AEs was 4(44.4%, 5(62.5%, and 1(10% for Low, High, and PL. No Grade 4 AEs occurred. CONCLUSIONS: Adverse events of aprepitant were more common in the treated groups. At the dose used in this two-week phase IB study, aprepitant showed biological activity, but no significant antiviral activity. TRIAL REGISTRATION: ClinicalTrials.gov NCT00428519.

  10. Lambda interferon (IFN-lambda), a type III IFN, is induced by viruses and IFNs and displays potent antiviral activity against select virus infections in vivo

    DEFF Research Database (Denmark)

    Ank, Nina; West, Hans; Bartholdy, Christina;

    2006-01-01

    Type III interferons (IFNs) (interleukin-28/29 or lambda interferon [IFN-lambda]) are cytokines with IFN-like activities. Here we show that several classes of viruses induce expression of IFN-lambda1 and -lambda2/3 in similar patterns. The IFN-lambdas were-unlike alpha/beta interferon (IFN......-alpha/beta)-induced directly by stimulation with IFN-alpha or -lambda, thus identifying type III IFNs as IFN-stimulated genes. In vitro assays revealed that IFN-lambdas have appreciable antiviral activity against encephalomyocarditis virus (EMCV) but limited activity against herpes simplex virus type 2 (HSV-2), whereas IFN...... had a more modest antiviral activity. Finally, pretreatment with IFN-lambda enhanced the levels of IFN-gamma in serum after HSV-2 infection. Thus, type III IFNs are expressed in response to most viruses and display potent antiviral activity in vivo against select viruses. The discrepancy between...

  11. Lambda Interferon (IFN-gamma), a Type III IFN, is induced by viruses and IFNs and displays potent antiviral activity against select virus infections in vivo

    DEFF Research Database (Denmark)

    Ank, Nina; West, Hans; Bartholdy, C.;

    2006-01-01

    Type III interferons (IFNs) (interleukin-28/29 or lambda interferon [IFN-lambda]) are cytokines with IFN-like activities. Here we show that several classes of viruses induce expression of IFN-lambda1 and -lambda2/3 in similar patterns. The IFN-lambdas were-unlike alpha/beta interferon (IFN......-alpha/beta)-induced directly by stimulation with IFN-alpha or -lambda, thus identifying type III IFNs as IFN-stimulated genes. In vitro assays revealed that IFN-lambdas have appreciable antiviral activity against encephalomyocarditis virus (EMCV) but limited activity against herpes simplex virus type 2 (HSV-2), whereas IFN...... had a more modest antiviral activity. Finally, pretreatment with IFN-lambda enhanced the levels of IFN-gamma in serum after HSV-2 infection. Thus, type III IFNs are expressed in response to most viruses and display potent antiviral activity in vivo against select viruses. The discrepancy between...

  12. An antiviral protein from Bougainvillea spectabilis roots; purification and characterisation.

    Science.gov (United States)

    Balasaraswathi, R; Sadasivam, S; Ward, M; Walker, J M

    1998-04-01

    An antiviral protein active against mechanical transmission of tomato spotted wilt virus was identified in the root tissues of Bougainvillea spectabilis Willd. Bougainvillea Antiviral Protein I (BAP I) was purified to apparent homogeneity from the roots of Bougainvillea by ammonium sulphate precipitation, CM- and DEAE-Sepharose chromatography and reverse phase HPLC. BAP I is a highly basic protein (pI value > 8.6) with an Mr of 28,000. The N-terminal sequence of BAP I showed homology with other plant antiviral proteins. Preliminary tests suggest that purified BAP I is capable of interfering with in vitro protein synthesis.

  13. [Antiviral activity of plant components. 1st communication: Flavonoids (author's transl)].

    Science.gov (United States)

    Wacker, A; Eilmes, H G

    1978-01-01

    Some drugs effective against influenza contain flavonoids. We therefore examined the antiviral effect of hesperidin, hesperidinmethylchalcon, trihydroxyethylrutin, catechol, quercitrin, rutin and aurantiin against vesicular stromatitis virus (VSV) action on mouse fibroblasts and that of hesperidin against influenza virus in HeLa cells system by means of dye uptake measurements (Finter) and by plaque reduction test, respectively. Preincubation of the cells with the flavonoids 6--8 h before virus addition was inevitable. Protection of cells against virus action persisted for about 24 h and it abruptly disappeared after an addition of hyaluronidase. Maximal inhibition of virus action was achieved with a concentration of 200 microgram/ml flavonoid.

  14. Antiviral activity of an aqueous extract derived from Aloe arborescens Mill. against a broad panel of viruses causing infections of the upper respiratory tract.

    Science.gov (United States)

    Glatthaar-Saalmüller, B; Fal, A M; Schönknecht, K; Conrad, F; Sievers, H; Saalmüller, A

    2015-09-15

    A number of antiviral therapies have evolved that may be effectively administered to treat respiratory viral diseases. But these therapies are very often of limited efficacy or have severe side effects. Therefore there is great interest in developing new efficacious and safe antiviral compounds e.g. based on the identification of compounds of herbal origin. Since an aqueous extract of Aloe arborescens Mill. shows antiviral activity against viruses causing infections of the upper respiratory tract in vitro we hypothesised that a product containing it such as Biaron C(®) could have an antiviral activity too. Antiviral activity of Bioaron C(®), an herbal medicinal product consisting of an aqueous extract of Aloe arborescens Mill., Vitamin C, and Aronia melanocarpa Elliot. succus, added as an excipient, was tested in vitro against a broad panel of viruses involved in upper respiratory tract infections. These studies included human adenovirus and several RNA viruses and were performed either with plaque reduction assays or with tests for the detection of a virus-caused cytopathic effect. Our studies demonstrated an impressive activity of Bioaron C(®) against members of the orthomyxoviridae - influenza A and influenza B viruses. Replication of both analysed influenza A virus strains - H1N1 and H3N2 - as well as replication of two analysed influenza B viruses - strains Yamagatal and Beiying - was significantly reduced after addition of Bioaron C(®) to the infected cell cultures. In contrast antiviral activity of Bioaron C(®) against other RNA viruses showed a heterogeneous pattern. Bioaron C(®) inhibited the replication of human rhinovirus and coxsackievirus, both viruses belonging to the family of picornaviridae and both representing non-enveloped RNA viruses. In vitro infections with respiratory syncytial virus and parainfluenza virus, both belonging to the paramyxoviridae, were only poorly blocked by the test substance. No antiviral activity of Bioaron C(®) was

  15. An Assay on the Antiviral Activity of Mulberry Leaf Extract%桑叶提取物的抗病毒活性检测

    Institute of Scientific and Technical Information of China (English)

    王辉; 吴莎; 孙毅凡; 江振友; 廖森泰; 刘凡

    2011-01-01

    % (IC50) value less than 12. 5 μg/mL. The residue water fraction and petroleum ether extract of many mulberry varieties from Morus atropurpurea Roxb. Exhibited high anti-influenza A (Flu A) activity. Leaf extracts of some mulberry varieties had certain inhibitory effect against Dengue virus type 2 (DV2). All four extracts of the 20 mulberry varieties had no inhibitory activity to Coxsackievirus B3 (CVB3). These results indicate that mulberry leaves contain rich and broad-spectrum antiviral active ingredients, but different mulberry species have different chemical compositions and various antiviral activities.

  16. Novel biotinylated lipid prodrugs of acyclovir for the treatment of herpetic keratitis (HK): transporter recognition, tissue stability and antiviral activity.

    Science.gov (United States)

    Vadlapudi, Aswani Dutt; Vadlapatla, Ramya Krishna; Earla, Ravinder; Sirimulla, Suman; Bailey, Jake Brain; Pal, Dhananjay; Mitra, Ashim K

    2013-08-01

    Biotinylated lipid prodrugs of acyclovir (ACV) were designed to target the sodium dependent multivitamin transporter (SMVT) on the cornea to facilitate enhanced cellular absorption of ACV. All the prodrugs were screened for in vitro cellular uptake, interaction with SMVT, docking analysis, cytotoxicity, enzymatic stability and antiviral activity. Uptake of biotinylated lipid prodrugs of ACV (B-R-ACV and B-12HS-ACV) was significantly higher than biotinylated prodrug (B-ACV), lipid prodrugs (R-ACV and 12HS-ACV) and ACV in corneal cells. Transepithelial transport across rabbit corneas indicated the recognition of the prodrugs by SMVT. Average Vina scores obtained from docking studies further confirmed that biotinylated lipid prodrugs possess enhanced affinity towards SMVT. All the prodrugs studied did not cause any cytotoxicity and were found to be safe and non-toxic. B-R-ACV and B-12HS-ACV were found to be relatively more stable in ocular tissue homogenates and exhibited excellent antiviral activity. Biotinylated lipid prodrugs demonstrated synergistic improvement in cellular uptake due to recognition of the prodrugs by SMVT on the cornea and lipid mediated transcellular diffusion. These biotinylated lipid prodrugs appear to be promising drug candidates for the treatment of herpetic keratitis (HK) and may lower ACV resistance in patients with poor clinical response.

  17. Antiviral activity produced by an IPNV-carrier EPC cell culture confers resistance to VHSV infection.

    Science.gov (United States)

    Jurado, María Teresa; García-Valtanen, Pablo; Estepa, Amparo; Perez, Luis

    2013-10-25

    Infectious pancreatic necrosis virus (IPNV), a fish birnavirus, can establish a persistent infection on epithelioma papulosum cyprinid (EPC) cells producing a carrier state where a small fraction of IPNV-infected cells is maintained in the culture after continuous subculture. The EPC(IPNV) cells are resistant to challenge with IPNV as well as to challenge with viral hemorrhagic septicemia virus (VHSV), a rhabdovirus. In this work, the antiviral effect of the IPNV carrier culture conditioned medium (EPC(IPNV)-CM) was tested and analyzed in detail. EPC cells treated with the carrier culture supernatant become protected against VHSV challenge. Size-fractionation by filtration and acid and heat treatment showed that the IPNV persistently infected cells release an acid-resistant soluble factor in the molecular weight fraction bellow 50 kDa. The capacity of the EPC(IPNV)-CM to induce cytokine genes in EPC cells was also determined by real-time RT-PCR. We found that there is a positive correlation between up-regulation of mx gene expression in EPC cells treated with EPC(IPNV)-CM and protection against VHSV challenge. Our findings indicate that the control of IPNV multiplication in the carrier culture as well as the interference with rhabdovirus replication are connected to the production and release of an antiviral (interferon-like) factor to the medium.

  18. microRNA control of interferons and interferon induced anti-viral activity.

    Science.gov (United States)

    Sedger, Lisa M

    2013-12-01

    Interferons (IFNs) are cytokines that are spontaneously produced in response to virus infection. They act by binding to IFN-receptors (IFN-R), which trigger JAK/STAT cell signalling and the subsequent induction of hundreds of IFN-inducible genes, including both protein-coding and microRNA genes. IFN-induced genes then act synergistically to prevent virus replication and create an anti-viral state. miRNA are therefore integral to the innate response to virus infection and are important components of IFN-mediated biology. On the other hand viruses also encode miRNAs that in some cases interfere directly with the IFN response to infection. This review summarizes the important roles of miRNAs in virus infection acting both as IFN-stimulated anti-viral molecules and as critical regulators of IFNs and IFN-stimulated genes. It also highlights how recent knowledge in RNA editing influence miRNA control of virus infection.

  19. Antiviral and virucidal activity of Chelidonium majus L. extract compared with Acyclovir against Herpes simplex virus type 1

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    M Sadeghpour Natanzi

    2017-02-01

    Full Text Available Background and aim: Herpes simplex virus is one of the most important human pathogenic viruses that may lead to oral herpes, keratoconjunctivitis and even encephalitis. A number of enzymes of the virus such as DNA polymerase can be targeted antiviral drugs. Acyclovir is used to treat infections of the virus, today due to drug resistance, need to do more research on finding new drugs, especially herbal medicines has increased. This study aimed to investigate the antiviral effect of methanol extract of Chelidonium majus compared with acyclovir against the virus in HeLa cell culture. Methods: In this experimental study, the toxicity of Chelidonium majus L. methanol extract and acyclovir on HeLa cell was determined with both MTT and Trypan blue methods. The antiviral effect of Chelidonium majus L. extract and acyclovir was evaluated in different concentration (1800- 1700- 1600- 1500- 1400 and 500- 100- 75- 50- 30-10 µg/ml and also in different times before, after and during of virus adsorption respectively.  The virus titer was measured by tissue culture infectious dose 50 TCID50(  method. The T-test method was used to comparing the effects of both compounds on virus. Results: The maximum non-toxic concentration of Chelidonium majus L. extract on HeLa cell was determined 1600 µg/ml that has the maximum inhibitory effect on HSV-1 replication. Acyclovir was shown low toxicity on HeLa cells.The 30 µg/ml concentration of acyclovir was considered for the next steps of the study.The highest inhibitory effect of the extract was observed 1 hour after absorption and the virus replication was suppressed completely by the acyclovir immediately after virus adsorption up to 8 hours after infection. Conclusion: The Chelidonium majus L. methanol extract has less effect than the acyclovir on inhibition of herpes simplex virus replication in a first few hours of infection. More research is needed to achieve effective compounds with antiviral activity of above

  20. Reduction of CCR5 with low-dose rapamycin enhances the antiviral activity of vicriviroc against both sensitive and drug-resistant HIV-1

    OpenAIRE

    2008-01-01

    Vicriviroc (VCV) is a chemokine (C-C motif) receptor 5 (CCR5) antagonist with potent anti-HIV activity that currently is being evaluated in phase III clinical trials. In the present study, donor CCR5 density (CCR5 receptors/CD4 lymphocytes) inversely correlated with VCV antiviral activity (Spearman's correlation test; r = 0.746, P = 0.0034). Low doses of the transplant drug rapamycin (RAPA) reduced CCR5 density and enhanced VCV antiviral activity. In drug interaction studies, the RAPA/VCV com...

  1. Asteltoxins with Antiviral Activities from the Marine Sponge-Derived Fungus Aspergillus sp. SCSIO XWS02F40

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    Yong-Qi Tian

    2015-12-01

    Full Text Available Two new asteltoxins named asteltoxin E (2 and F (3, and a new chromone (4, together with four known compounds were isolated from a marine sponge–derived fungus, Aspergillus sp. SCSIO XWS02F40. The structures of the compounds (1–7 were determined by the extensive 1D- and 2D-NMR spectra, and HRESIMS spectrometry. All the compounds were tested for their antiviral (H1N1 and H3N2 activity. Compounds 2 and 3 showed significant activity against H3N2 with the prominent IC50 values of 6.2 ± 0.08 and 8.9 ± 0.3 μM, respectively. In addition, compound 2 also exhibited inhibitory activity against H1N1 with an IC50 value of 3.5 ± 1.3 μM.

  2. Asteltoxins with Antiviral Activities from the Marine Sponge-Derived Fungus Aspergillus sp. SCSIO XWS02F40.

    Science.gov (United States)

    Tian, Yong-Qi; Lin, Xiu-Ping; Wang, Zhen; Zhou, Xue-Feng; Qin, Xiao-Chu; Kaliyaperumal, Kumaravel; Zhang, Tian-Yu; Tu, Zheng-Chao; Liu, Yonghong

    2015-12-26

    Two new asteltoxins named asteltoxin E (2) and F (3), and a new chromone (4), together with four known compounds were isolated from a marine sponge-derived fungus, Aspergillus sp. SCSIO XWS02F40. The structures of the compounds (1-7) were determined by the extensive 1D- and 2D-NMR spectra, and HRESIMS spectrometry. All the compounds were tested for their antiviral (H1N1 and H3N2) activity. Compounds 2 and 3 showed significant activity against H3N2 with the prominent IC50 values of 6.2 ± 0.08 and 8.9 ± 0.3 μM, respectively. In addition, compound 2 also exhibited inhibitory activity against H1N1 with an IC50 value of 3.5 ± 1.3 μM.

  3. In vitro schistosomicidal and antiviral activities of Arctium lappa L. (Asteraceae) against Schistosoma mansoni and Herpes simplex virus-1.

    Science.gov (United States)

    Dias, Mirna Meana; Zuza, Ohana; Riani, Lorena R; de Faria Pinto, Priscila; Pinto, Pedro Luiz Silva; Silva, Marcos P; de Moraes, Josué; Ataíde, Ana Caroline Z; de Oliveira Silva, Fernanda; Cecílio, Alzira Batista; Da Silva Filho, Ademar A

    2017-10-01

    Schistosomiasis and herpes diseases represent serious issues to the healthcare systems, infecting a large number of people worldwide, mainly in developing countries. Arctium lappa L. (Asteraceae), known as "bardana" and "burdock", is a medicinal plant popularly used for several purposes, including as antiseptic. In this study, we evaluated the in vitro schistosomicidal and antiherpes activities of the crude extract of A. lappa, which have not yet been described. Fruits of A. lappa L. were extracted by maceration with ethanol: H2O (96:4 v/v) in order to obtain the hydroalcoholic extract of A. lappa (AL). In vitro schistosomicidal assays were assessed against adult worms of Schistosoma mansoni, while the in vitro antiviral activity of AL was evaluated on replication of Herpes simplex virus type-1 (HSV-1). Cell viability was measured by MTT assay, using Vero cells and chemical composition of AL was determined by qualitative UPLC-ESI-QTOF-MS analysis. UPLC-ESI-QTOF-MS analysis of AL revealed the presence of dibenzylbutyrolactone lignans, such as arctiin and arctigenin. Results showed that AL was not cytotoxic to Vero cells even when tested at 400μg/mL. qPCR results indicated a significant viral load decreased for all tested concentrations of AL (400, 50, and 3.125μg/mL), which showed similar antiviral effect to acyclovir (50μg/mL) when tested at 400μg/mL. Also, AL (400, 200, and 100μg/mL) caused 100% mortality and significantly reduction on motor activity of all adult worms of S. mansoni. Confocal laser scanning microscopy showed tegumental morphological alterations and changes on the numbers of tubercles of S. mansoni worms in a dose-dependent manner after treatment with AL. This report provides the first evidence for the in vitro schistosomicidal and antiherpes activities of AL, opening the route to further schistosomicidal and antiviral studies with AL and their compounds, especially lignans. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  4. High serum palmitic acid is associated with low antiviral effects of interferon-based therapy for hepatitis C virus.

    Science.gov (United States)

    Miyake, Teruki; Hiasa, Yoichi; Hirooka, Masashi; Tokumoto, Yoshio; Watanabe, Takao; Furukawa, Shinya; Ueda, Teruhisa; Yamamoto, Shin; Kumagi, Teru; Miyaoka, Hiroaki; Abe, Masanori; Matsuura, Bunzo; Onji, Morikazu

    2012-11-01

    Hepatitis C virus (HCV) infection alters fatty acid synthesis and metabolism in association with HCV replication. The present study examined the effect of serum fatty acid composition on interferon (IFN)-based therapy. Fifty-five patients with HCV were enrolled and received IFN-based therapy. Patient characteristics, laboratory data (including fatty acids), and viral factors that could be associated with the anti-HCV effects of IFN-based therapy were evaluated. The effects of individual fatty acids on viral replication and IFN-based therapy were also examined in an in-vitro system. Multivariate logistic regression analysis showed that the level of serum palmitic acid before treatment and HCV genotype were significant predictors for rapid virological response (RVR), early virological response (EVR), and sustained virological response (SVR). High levels of palmitic acid inhibited the anti-HCV effects of IFN-based therapy. HCV replication assays confirmed the inhibitory effects of palmitic acid on anti-HCV therapy. The concentration of serum palmitic acid is an independent predictive factor for RVR, EVR, and SVR in IFN-based antiviral therapy. These results suggest that the effect of IFN-based antiviral therapy in patients with HCV infection might be enhanced by treatment that modulates palmitic acid levels.

  5. Myxoma Virus dsRNA Binding Protein M029 Inhibits the Type I IFN-Induced Antiviral State in a Highly Species-Specific Fashion

    Science.gov (United States)

    Rahman, Masmudur M.; McFadden, Grant

    2017-01-01

    Myxoma virus (MYXV) is a Leporipoxvirus that possesses a specific rabbit-restricted host tropism but exhibits a much broader cellular host range in cultured cells. MYXV is able to efficiently block all aspects of the type I interferon (IFN)-induced antiviral state in rabbit cells, partially in human cells and very poorly in mouse cells. The mechanism(s) of this species-specific inhibition of type I IFN-induced antiviral state is not well understood. Here we demonstrate that MYXV encoded protein M029, a truncated relative of the vaccinia virus (VACV) E3 double-stranded RNA (dsRNA) binding protein that inhibits protein kinase R (PKR), can also antagonize the type I IFN-induced antiviral state in a highly species-specific manner. In cells pre-treated with type I IFN prior to infection, MYXV exploits M029 to overcome the induced antiviral state completely in rabbit cells, partially in human cells, but not at all in mouse cells. However, in cells pre-infected with MYXV, IFN-induced signaling is fully inhibited even in the absence of M029 in cells from all three species, suggesting that other MYXV protein(s) apart from M029 block IFN signaling in a species-independent manner. We also show that the antiviral state induced in rabbit, human or mouse cells by type I IFN can inhibit M029-knockout MYXV even when PKR is genetically knocked-out, suggesting that M029 targets other host proteins for this antiviral state inhibition. Thus, the MYXV dsRNA binding protein M029 not only antagonizes PKR from multiple species but also blocks the type I IFN antiviral state independently of PKR in a highly species-specific fashion. PMID:28157174

  6. Antiviral activity and possible mechanism of action of constituents identified in Paeonia lactiflora root toward human rhinoviruses.

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    Luong Thi My Ngan

    Full Text Available Human rhinoviruses (HRVs are responsible for more than half of all cases of the common cold and cost billions of USD annually in medical visits and missed school and work. An assessment was made of the antiviral activities and mechanisms of action of paeonol (PA and 1,2,3,4,6-penta-O-galloyl-β-D-glucopyranose (PGG from Paeonia lactiflora root toward HRV-2 and HRV-4 in MRC5 cells using a tetrazolium method and real-time quantitative reverse transcription polymerase chain reaction and enzyme-linked immunosorbent assay. Results were compared with those of a reference control ribavirin. Based on 50% inhibitory concentration values, PGG was 13.4 and 18.0 times more active toward HRV-2 (17.89 μM and HRV-4 (17.33 μM in MRC5 cells, respectively, than ribavirin. The constituents had relatively high selective index values (3.3->8.5. The 100 μg/mL PA and 20 μg/mL PGG did not interact with the HRV-4 particles. These constituents inhibited HRV-4 infection only when they were added during the virus inoculation (0 h, the adsorption period of HRVs, but not after 1 h or later. Moreover, the RNA replication levels of HRVs were remarkably reduced in the MRC5 cultures treated with these constituents. These findings suggest that PGG and PA may block or reduce the entry of the viruses into the cells to protect the cells from the virus destruction and abate virus replication, which may play an important role in interfering with expressions of rhinovirus receptors (intercellular adhesion molecule-1 and low-density lipoprotein receptor, inflammatory cytokines (interleukin (IL-6, IL-8, tumor necrosis factor, interferon beta, and IL-1β, and Toll-like receptor, which resulted in diminishing symptoms induced by HRV. Global efforts to reduce the level of synthetic drugs justify further studies on P. lactiflora root-derived materials as potential anti-HRV products or lead molecules for the prevention or treatment of HRV.

  7. Antiviral Activity of Alkaloids from Cynanchum komarovii%牛心朴子草中生物碱的抑制植物病毒活性研究

    Institute of Scientific and Technical Information of China (English)

    黄治强; 刘玉秀; 范志金; 汪清民; 李广仁; 姚宇澄; 于学舜; 黄润秋

    2007-01-01

    With the aim of searching antiviral substances to tobacco mosaic virus (TMV),alkaloid extracts from the alcohol extract of Cynanchum komarovii were isolated through gel chromatograph. 7-Demethoxytylophorine (antofine,1)was present as the primary content of the alkaloid,another four alkaloids,6 -hydroxyl -2,3 - dimethoxyphenanthroindolizidine (2_),7-demethoxytylophorine N-oxide (3_),14-hydroxyantofine N-oxide (4_) and 2,3 -dimethoxy-6-(3 -oxobutyl) -7,9,10,11,11a,12-hexahydrobenzo [f] pyrrolo [1,2-b] isoquinoline (5_) wereobtained at lower levels in the extract. Among them,the known alkaloid (2_) was isolated from Cynanchum komaroviifor the first time. A half-leaf method was used to assess the inhibitory activity of the five alkaloids against TMV. It wasfound that the alkaloids (1_) and (2_) exhibited excellent antiviral activity and the both alkaloids were responsible for theantiviral activity of the alkaloid extracts from the alcohol extract of Cynanchum komarovii. The presence of free nitrogenin tertiary amine and phenanthrene ring were essential for high antiviral activity.%牛心朴子草广泛分布于我国西北旱沙荒漠地带,笔者发现其提取物中生物碱部位对危害极大的烟草花叶病毒(TMV)具有很高的抑制活性.生物活性跟踪与色谱分离、结构鉴定确认该生物碱属于菲并吲哚里西啶,活性成份为安托芬(1_)和6-羟基-2,3-二甲氧基菲并吲哚里西啶(2_).此外,还分离得到另外三种生物碱.构效关系表明氮上孤电子对和菲环对高的抗病毒活性是必要的.

  8. Development of a new tacaribe arenavirus infection model and its use to explore antiviral activity of a novel aristeromycin analog.

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    Brian B Gowen

    Full Text Available BACKGROUND: A growing number of arenaviruses can cause a devastating viral hemorrhagic fever (VHF syndrome. They pose a public health threat as emerging viruses and because of their potential use as bioterror agents. All of the highly pathogenic New World arenaviruses (NWA phylogenetically segregate into clade B and require maximum biosafety containment facilities for their study. Tacaribe virus (TCRV is a nonpathogenic member of clade B that is closely related to the VHF arenaviruses at the amino acid level. Despite this relatedness, TCRV lacks the ability to antagonize the host interferon (IFN response, which likely contributes to its inability to cause disease in animals other than newborn mice. METHODOLOGY/PRINCIPAL FINDINGS: Here we describe a new mouse model based on TCRV challenge of AG129 IFN-α/β and -γ receptor-deficient mice. Titration of the virus by intraperitoneal (i.p. challenge of AG129 mice resulted in an LD(50 of ∼100 fifty percent cell culture infectious doses. Virus replication was evident in the serum, liver, lung, spleen, and brain 4-8 days after inoculation. MY-24, an aristeromycin derivative active against TCRV in cell culture at 0.9 µM, administered i.p. once daily for 7 days, offered highly significant (P<0.001 protection against mortality in the AG129 mouse TCRV infection model, without appreciably reducing viral burden. In contrast, in a hamster model of arenaviral hemorrhagic fever based on challenge with clade A Pichinde arenavirus, MY-24 did not offer significant protection against mortality. CONCLUSIONS/SIGNIFICANCE: MY-24 is believed to act as an inhibitor of S-adenosyl-L-homocysteine hydrolase, but our findings suggest that it may ameliorate disease by blunting the effects of the host response that play a role in disease pathogenesis. The new AG129 mouse TCRV infection model provides a safe and cost-effective means to conduct early-stage pre-clinical evaluations of candidate antiviral therapies that target

  9. Antiviral activity of extracts from Morinda citrifolia leaves and chlorophyll catabolites, pheophorbide a and pyropheophorbide a, against hepatitis C virus.

    Science.gov (United States)

    Ratnoglik, Suratno Lulut; Aoki, Chie; Sudarmono, Pratiwi; Komoto, Mari; Deng, Lin; Shoji, Ikuo; Fuchino, Hiroyuki; Kawahara, Nobuo; Hotta, Hak

    2014-03-01

    The development of complementary and/or alternative drugs for treatment of hepatitis C virus (HCV) infection is still needed. Antiviral compounds in medicinal plants are potentially good targets to study. Morinda citrifolia is a common plant distributed widely in Indo-Pacific region; its fruits and leaves are food sources and are also used as a treatment in traditional medicine. In this study, using a HCV cell culture system, it was demonstrated that a methanol extract, its n-hexane, and ethyl acetate fractions from M. citrifolia leaves possess anti-HCV activities with 50%-inhibitory concentrations (IC(50)) of 20.6, 6.1, and 6.6 μg/mL, respectively. Bioactivity-guided purification and structural analysis led to isolation and identification of pheophorbide a, the major catabolite of chlorophyll a, as an anti-HCV compound present in the extracts (IC(50) = 0.3 μg/mL). It was also found that pyropheophorbide a possesses anti-HCV activity (IC(50) = 0.2 μg/mL). The 50%-cytotoxic concentrations (CC(50)) of pheophorbide a and pyropheophorbide a were 10.0 and 7.2 μg/mL, respectively, their selectivity indexes being 33 and 36, respectively. On the other hand, chlorophyll a, sodium copper chlorophyllin, and pheophytin a barely, or only marginally, exhibited anti-HCV activities. Time-of-addition analysis revealed that pheophorbide a and pyropheophorbide a act at both entry and the post-entry steps. The present results suggest that pheophorbide a and its related compounds would be good candidates for seed compounds for developing antivirals against HCV.

  10. Rationally designed interfacial peptides are efficient in vitro inhibitors of HIV-1 capsid assembly with antiviral activity.

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    Rebeca Bocanegra

    Full Text Available Virus capsid assembly constitutes an attractive target for the development of antiviral therapies; a few experimental inhibitors of this process for HIV-1 and other viruses have been identified by screening compounds or by selection from chemical libraries. As a different, novel approach we have undertaken the rational design of peptides that could act as competitive assembly inhibitors by mimicking capsid structural elements involved in intersubunit interfaces. Several discrete interfaces involved in formation of the mature HIV-1 capsid through polymerization of the capsid protein CA were targeted. We had previously designed a peptide, CAC1, that represents CA helix 9 (a major part of the dimerization interface and binds the CA C-terminal domain in solution. Here we have mapped the binding site of CAC1, and shown that it substantially overlaps with the CA dimerization interface. We have also rationally modified CAC1 to increase its solubility and CA-binding affinity, and designed four additional peptides that represent CA helical segments involved in other CA interfaces. We found that peptides CAC1, its derivative CAC1M, and H8 (representing CA helix 8 were able to efficiently inhibit the in vitro assembly of the mature HIV-1 capsid. Cocktails of several peptides, including CAC1 or CAC1M plus H8 or CAI (a previously discovered inhibitor of CA polymerization, or CAC1M+H8+CAI, also abolished capsid assembly, even when every peptide was used at lower, sub-inhibitory doses. To provide a preliminary proof that these designed capsid assembly inhibitors could eventually serve as lead compounds for development of anti-HIV-1 agents, they were transported into cultured cells using a cell-penetrating peptide, and tested for antiviral activity. Peptide cocktails that drastically inhibited capsid assembly in vitro were also able to efficiently inhibit HIV-1 infection ex vivo. This study validates a novel, entirely rational approach for the design of capsid

  11. RING domain is essential for the antiviral activity of TRIM25 from orange spotted grouper.

    Science.gov (United States)

    Yang, Ying; Huang, Youhua; Yu, Yepin; Yang, Min; Zhou, Sheng; Qin, Qiwei; Huang, Xiaohong

    2016-08-01

    Tripartite motif-containing 25 (TRIM25) has been demonstrated to exert crucial roles in the regulation of innate immune signaling. However, the roles of fish TRIM25 in antiviral immune response still remained uncertain. Here, a novel fish TRIM25 gene from orange spotted grouper (EcTRIM25) was cloned and its roles in grouper virus infection were elucidated. EcTRIM25 encoded a 734-aa protein which shared 68% identity to large yellow croaker (Larimichthys crocea). Amino acid alignment showed that EcTRIM25 contained three conserved domains, including a RING-finger domain, a B box/coiled-coil domain and a SPRY domain. In healthy grouper, the transcript of EcTRIM25 was predominantly detected in skin, spleen and intestine. After stimulation with Singapore grouper iridovirus (SGIV) or poly I:C, the relative expression of EcTRIM25 in grouper spleen was significantly increased at the early stage of injection. Subcellular localization analysis showed that EcTRIM25 distributed throughout the cytoplasm in grouper cells. Notably, the deletion RING domain affected its accurate localization and displayed microtubule like structures or bright aggregates in GS cells. After incubation with SGIV or red spotted grouper nervous necrosis virus (RGNNV), overexpression of full length of EcTRIM25 in vitro significantly decreased the viral gene transcription of SGIV and RGNNV. Consistently, the deletion of RING domain obviously affected the inhibitory effect of EcTRIM25. Furthermore, overexpression of EcTRIM25 significantly increased the expression level of interferon related signaling molecules, including interferon regulatory factor (IRF) 3, interferon-induced 35-kDa protein (IFP35), MXI, IRF7 and myeloid differentiation factor 88 (MyD88), suggesting that the positive regulation of interferon immune response by EcTRIM25 might affected RGNNV replication directly. Meanwhile, the expression levels of pro-inflammation cytokines were differently regulated by the ectopic expression of EcTRIM25

  12. The novel primaquine derivatives of N-alkyl, cycloalkyl or aryl urea: synthesis, cytostatic and antiviral activity evaluations.

    Science.gov (United States)

    Dzimbeg, G; Zorc, B; Kralj, M; Ester, K; Pavelić, K; Andrei, G; Snoeck, R; Balzarini, J; De Clercq, E; Mintas, M

    2008-06-01

    The novel urea primaquine derivatives 3a-i were prepared by aminolysis of benzotriazolide 2 with the corresponding amine in the presence or absence of triethylamine. Compound 2 was prepared by acylation of primaquine with 1-benzotriazole carboxylic acid chloride. Among all compounds evaluated, the pyridine derivative 3h exhibited the best cytostatic activities against colon carcinoma, human T-lymphocyte and murine leukemia. However, this compound showed also rather marked cytotoxicity towards human normal fibroblasts. The highest selectivity in the inhibitory effects on human malignant tumor cell lines vs. normal fibroblasts was found for ureas 3c, 3d and 3g. Results of broad antiviral evaluation showed that pyridine and phenethyl derivatives of urea 3h and 3g exhibited some selective inhibition against cytomegalovirus.

  13. Synthesis and antiviral activity of the carbocyclic analogues of 5-ethyl-2'-deoxyuridine and of 5-ethynyl-2'-deoxyuridine.

    Science.gov (United States)

    Shealy, Y F; O'Dell, C A; Arnett, G; Shannon, W M

    1986-01-01

    The carbocyclic analogue of the antiviral agent 5-ethyl-2'-deoxyuridine (EDU) was synthesized by two routes. The pivotal step in the first route is the reaction of lithium dimethylcuprate with the carbocyclic analogue of 5-(bromomethyl)-2'-deoxyuridine dibenzoate (6). The second route is based on the synthesis of the carbocyclic analogue of 5-ethynyl-2'-deoxyuridine (12) by a coupling reaction catalyzed by bis(triphenylphosphine)palladium(II) chloride and copper(I) iodide, a method reported recently (Robins and Barr) for the synthesis of the true nucleoside 5-ethynyl-2'-deoxyuridine (1b). The carbocyclic analogue of EDU inhibits the replication of type 1 and type 2 herpes simplex viruses in Vero cells. The carbocyclic analogue of 5-ethynyl-2'-deoxyuridine has modest activity against herpes simplex virus, types 1 and 2.

  14. Antiviral activity of the oseltamivir and Melissa officinalis L. essential oil against avian influenza A virus (H9N2).

    Science.gov (United States)

    Pourghanbari, Gholamhosein; Nili, Hasan; Moattari, Afagh; Mohammadi, Ali; Iraji, Aida

    2016-06-01

    Lemon balm derivatives are going to acquire a novelty as natural and potent remedy for treatment of viral infections since the influenza viruses are developing resistance to the current antivirals widely. Oseltamivir, Melissa officinalis essential oil (MOEO) and their synergistic efficacy against avian influenza virus (AIV) subtype H9N2 were evaluated in vitro in MDCK cells at different time exposure by using TCID50, HA, Real Time PCR and HI assay. The results showed that MOEO could inhibit replication of AVI through the different virus replication phase (P ≤ 0.05). Also the highest antiviral activity of MOEO was seen when AIV incubated with MOEO before cell infection. The TCID50/ml was reduced 1.3-2.1, 2.3-2.8, 3.7-4.5 log 10 than control group (5.6 log 10), HAU/50 µl was decreased 85-94, 71.4-94, 71.4-94 % and viral genome copy number/µl was brought down 68-95, 90-100, 89.6-99.9 % at pre-infection, post-infection and simultaneous stage, respectively. Hemagglutination inhibition result showed the MOEO was not able to inhibit agglutination of the chicken red blood cell (cRBC). Replication of the AVI was suppressed by the different concentration of oseltamivir completely or near 100 %. Also oseltamivir showed a synergistic activity with MOEO especially when oseltamivir concentration reduced under 0.005 mg/ml. The chemical composition was examined by GC-MS analysis and Its main constituents were identified as monoterpenaldehydes citral a, citral b. In conclusion, the findings of the study showed that lemon balm essential oil could inhibit influenza virus replication through different replication cycle steps especially throughout the direct interaction with the virus particles.

  15. Application of "hydrogen bonding interaction" in new drug development: design, synthesis, antiviral activity, and SARs of thiourea derivatives.

    Science.gov (United States)

    Lu, Aidang; Wang, Ziwen; Zhou, Zhenghong; Chen, Jianxin; Wang, Qingmin

    2015-02-11

    A series of simple thiourea derivatives were designed based on the structure of natural product harmine and lead compound and synthesized from amines in one step. The antiviral activity of these thiourea derivatives was evaluated. Most of them exhibited significantly higher anti-TMV activity than commercial plant virucides ribavirin, harmine, and lead compound. The hydrogen bond was found to be important but not the more the better. The optimal compound (R,R)-20 showed the best anti-TMV activity in vitro and in vivo (in vitro activity, 75%/500 μg/mL and 39%/100 μg/mL; inactivation activity, 71%/500 μg/mL and 35%/100 μg/mL; curative activity, 73%/500 μg/mL and 37%/100 μg/mL; protection activity, 69%/500 μg/mL and 33%/100 μg/mL), which is significantly higher than that of Ningnanmycin. The systematic study provides strong evidence that these simple thiourea derivatives could become potential TMV inhibitors.

  16. Evaluation of the cytotoxic effect and antibacterial, antifungal, and antiviral activities of Hypericum triquetrifolium Turra essential oils from Tunisia

    Science.gov (United States)

    2013-01-01

    Background A number of bio-active secondary metabolites have been identified and reported for several Hypericum species. Many studies have reported the potential use of the plant extracts against several pathogens. However, Hypericum triquetrifolium is one of the least studied species for its antimicrobial activity. The aim of the present study was to evaluate the cytotoxic effect of the essential oils of Hypericum triquetrifolium as well as their antimicrobial potential against coxsakievirus B3 and a range of bacterial and fungal strains. Methods The essential oils of Hypericum triquetrifolium harvested from five different Tunisian localities (Fondouk DJedid, Bou Arada, Bahra, Fernana and Dhrea Ben Jouder) were evaluated for their antimicrobial activities by micro-broth dilution methods against bacterial and fungal strains. In addition, the cytotoxic effect and the antiviral activity of these oils were carried out using Vero cell lines and coxsakievirus B3. Results The results showed a good antibacterial activities against a wide range of bacterial strains, MIC values ranging between 0.39-12.50 mg/ml and MBC values between 1.56-25.0 mg/ml. In addition, the essential oils showed promising antifungal activity with MIC values ranging between 0.39 μg/mL and 12.50 μg/mL; MFC values ranged between 3.12 μg/mL and 25.00 μg/mL; a significant anticandidal activity was noted (MIC values comprised between 0.39 μg/mL and 12.50 μg/mL). Although their low cytotoxic effect (CC50 ranged between 0.58 mg/mL and 12.00 mg/mL), the essential oils did not show antiviral activity against coxsakievirus B3. Conclusion The essential oils obtained from Hypericum triquetrifolium can be used as antimicrobial agents and could be safe at non cytotoxic doses. As shown for the tested essential oils, comparative analysis need to be undertaken to better characterize also the antimicrobial activities of Hypericum triquetrifolium extracts with different solvents as well as their

  17. Perspective of Use of Antiviral Peptides against Influenza Virus

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    Sylvie Skalickova

    2015-10-01

    Full Text Available The threat of a worldwide influenza pandemic has greatly increased over the past decade with the emergence of highly virulent avian influenza strains. The increased frequency of drug-resistant influenza strains against currently available antiviral drugs requires urgent development of new strategies for antiviral therapy, too. The research in the field of therapeutic peptides began to develop extensively in the second half of the 20th century. Since then, the mechanisms of action for several peptides and their antiviral prospect received large attention due to the global threat posed by viruses. Here, we discussed the therapeutic properties of peptides used in influenza treatment. Peptides with antiviral activity against influenza can be divided into three main groups. First, entry blocker peptides such as a Flupep that interact with influenza hemagglutinin, block its binding to host cells and prevent viral fusion. Second, several peptides display virucidal activity, disrupting viral envelopes, e.g., Melittin. Finally, a third set of peptides interacts with the viral polymerase complex and act as viral replication inhibitors such as PB1 derived peptides. Here, we present a review of the current literature describing the antiviral activity, mechanism and future therapeutic potential of these influenza antiviral peptides.

  18. Evaluation of the potential anti-viral activity of microRNAs in rainbow trout (Oncorhynchus mykiss)

    DEFF Research Database (Denmark)

    Bela-Ong, Dennis; Schyth, Brian Dall; Lorenzen, Niels

    2013-01-01

    have previously observed and validated that the fishspecific miRNAs, miR-462 and miR-731, were among the most highly expressed miRNAs in rainbow trout liver following Viral hemorrhagic septicemia virus (VHSV) infection. These miRNAs were also upregulated in the liver and muscle (vaccination site......) of fish vaccinated with a DNA vaccine encoding the glycoprotein gene of VHSV. Recent studies further suggest that the expression of these miRNAs is induced by interferons. In order to analyze if miRNA-462 and miRNA-731 have any antiviral effects, we designed inhibitory synthetic oligonucleotides called...... antagomiRs or anti-miRNAs. These antagomiRs were injected intraperitoneally into rainbow trout fingerlings followed by exposure of the fish to VHSV. Development of disease and levels of infection will be analysed and compared to data from fish treated with control miRNAs....

  19. Antiviral activity of dolutegravir in subjects with failure on an integrase inhibitor-based regimen: week 24 phase 3 results from VIKING-3

    Science.gov (United States)

    Nichols, G; Mills, A; Grossberg, R; Lazzarin, A; Maggiolo, F; Molina, J; Pialoux, G; Wright, D; Ait-Khaled, M; Huang, J; Vavro, C; Wynne, B; Yeo, J

    2012-01-01

    Background VIKING-3 aimed to examine efficacy and safety of dolutegravir (DTG) 50 mg twice daily in patients with resistance to multiple ARV classes, including integrase inhibitors (INI). Methods RAL and/or EVG-resistant (current or historical) adult subjects with screening plasma HIV-1 RNA ≥500 c/mL and resistance to ≥2 other ART classes received open-label DTG 50 mg BID while continuing their failing regimen (without RAL/EVG). At Day 8 the background regimen was optimised and DTG continued. Activity of the optimized background regimen (OBR) was determined by Monogram Net Assessment. Primary endpoints were antiviral efficacy at Day 8 and Week 24. Results 183 subjects enrolled, 124 with INI-resistance at screening and 59 with historical (but no screening) resistance. Population was advanced: at BL, median CD4 140, prior ART 13 yrs, 56% CDC Class C; 79% had >2 NRTI, 75% >1 NNRTI, and 70% >2 PI resistance-associated mutations, and 61% had non-R5 HIV detected. Of the 114 subjects who had the opportunity to complete 24 weeks on study before data cutoff, 72 (63%) had 1 log HIV RNA decline of 2, respectively. Discontinuations due to adverse events were uncommon (6/183, 3%); the most common drug-related AEs were diarrhoea, nausea and headache, each reported in only 5% of subjects. Conclusion A majority of the highly treatment-experienced subjects in VIKING-3 achieved suppression with DTG-based therapy. Responses were associated with Baseline IN genotype but not OSS, highlighting the importance and independence of DTG antiviral activity. DTG had a low rate of discontinuation due to adverse events at 50 mg BID in this advanced patient population.

  20. Evaluation of antibacterial and antiviral activity of N-arylamides of 9-methyl and 9-methoxyphenazine-1-carboxylic acids – inhibitors of the phage T7 model transctiption

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    Hovorun D. M.

    2012-12-01

    Full Text Available Aim. Search for compounds with antibacterial and antiviral properties among N-arylamides of 9-substituted phenazine-1-carboxylic acids (PCA, inhibitors of the RNA synthesis. Methods. Influence of N-aryl-amides on the RNA synthesis was tested in vitro in the model system of the DNA-dependent RNA polymerase of phage T7 (T7 RNAP. Antimicrobial activities of the N-arylamides against bacteria Erysipelothrix rhusiopathiae VR-2 var. IVM, Klebsiella spp. and Escherichia coli ATCC25922 were investigated by the method of two-fold dilution in a liquid medium. Antiviral effects against Bovine Viral Diarrhea Virus (BVDV and cytotoxicity of the N-arylamides were evaluated using Madin-Darby bovine kidney (MDBK cells. Results. Twenty N-arylamides appeared to be efficacious inhibitors of the RNA synthesis at concent- rations of 0.48–61 µМ. The compound 16 proved to be the most effective inhibitor of T7 RNAP with the IC50 value being 0.48 µМ. Fourteen N-arylamides demonstrated antibacterial properties against gram positive and gram negative bacteria at the 0.1–10 µg/ml concentrations. A number of the N-arylamides revealed a multiplicity of their antimicrobial actions: 7 compounds against two bacteria and two compounds, 2 and 3, against three bacteria investigated. N-arylamides 16 and 26 showed high inhibitory activity as to BVDV with the IC50 values 0.43 and 0.88 µg/ml and SI values 160 and 10 correspondingly. Conclusions. The obtained data evidence that the most likely targets of the N-arylamides 9-substituted PCA in bacteria and viruses are their RNA synthesizing complexes.

  1. Critical role for cross-linking of trimeric lectin domains of surfactant protein D in antiviral activity against influenza A virus

    DEFF Research Database (Denmark)

    Tecle, Tesfaldet; White, Mitchell R; Sørensen, Grith Lykke

    2008-01-01

    and antiviral activity of NCRDs as assessed by haemagglutination and neuraminidase inhibition and by viral neutralization. mAb-mediated cross-linking also enabled NCRDs to induce viral aggregation and to increase viral uptake by neutrophils and virus-induced respiratory burst responses by these cells...

  2. Study on the Rationality for Antiviral Activity of Flos Lonicerae Japonicae-Fructus Forsythiae Herb Chito-Oligosaccharide via Integral Pharmacokinetics.

    Science.gov (United States)

    Zhou, Wei; Yin, Ailing; Shan, Jinjun; Wang, Shouchuan; Cai, Baochang; Di, Liuqing

    2017-04-20

    In the present study, the rationality for the antiviral effect (H1N1 virus) of Flos Lonicerae Japonicae (FLJ, named JinYinHua)-Fructus forsythiae (FF, named LianQiao) herb couple preparations improved by chito-oligosaccharide (COS) was investigated. We found that the improvement of antiviral activity for four preparations attributed to the enhancement of bioavailability for the FLJ-FF herb couple in vivo, and that caffeic acid derivatives are the most important type of components for antiviral activity. The anti-Influenza virus activity-half maximal inhibitory concentration (IC50), not area under concentration (AUC) was considered as the weighting factor for integrating the pharmacokinetics of caffeic acid derivatives. It was found that the integral absorption, both in vitro and in vivo, especially that in Shuang-Huang-Lian, can be improved significantly by COS, an absorption enhancer based on tight junction. The results indicated that the antiviral activity in four preparations improved by COS was mainly attributed to the integral absorption enhancement of caffeic acid derivatives.

  3. The innate antiviral immune system of the cat: molecular tools for the measurement of its state of activation.

    Science.gov (United States)

    Robert-Tissot, Céline; Rüegger, Vera L; Cattori, Valentino; Meli, Marina L; Riond, Barbara; Gomes-Keller, Maria Alice; Vögtlin, Andrea; Wittig, Burghardt; Juhls, Christiane; Hofmann-Lehmann, Regina; Lutz, Hans

    2011-10-15

    The innate immune system plays a central role in host defence against viruses. While many studies portray mechanisms in early antiviral immune responses of humans and mice, much remains to be discovered about these mechanisms in the cat. With the objective of shedding light on early host-virus interactions in felids, we have developed 12 real-time TaqMan(®) qPCR systems for feline genes relevant to innate responses to viral infection, including those encoding for various IFNα and IFNω subtypes, IFNβ, intracellular antiviral factor Mx, NK cell stimulator IL-15 and effectors perforin and granzyme B, as well as Toll-like receptors (TLRs) 3 and 8. Using these newly developed assays and others previously described, we measured the relative expression of selected markers at early time points after viral infection in vitro and in vivo. Feline embryonic fibroblasts (FEA) inoculated with feline leukemia virus (FeLV) indicated peak levels of IFNα, IFNβ and Mx expression already 6h after infection. In contrast, Crandell-Rees feline kidney (CrFK) cells inoculated with feline herpes virus (FHV) responded to infection with high levels of IFNα and IFNβ only after 24h, and no induction of Mx could be detected. In feline PBMCs challenged in vitro with feline immunodeficiency virus (FIV), maximal expression levels of IFNα, β and ω subtype genes as well as IL-15 and TLRs 3, 7 and 8 were measured between 12 and 24h after infection, whereas expression levels of proinflammatory cytokine gene IL-6 were consistently downregulated until 48h post inoculation. A marginal upregulation of granzyme B was also observed within 3h after infection. In an in vivo experiment, cats challenged with FIV exhibited a 2.4-fold increase in IFNα expression in blood 1 week post infection. We furthermore demonstrate the possibility of stimulating feline immune cells in vitro with various immune response modifiers (IRMs) already known for their immunostimulatory properties in mice and humans, namely

  4. CGP 53437, an orally bioavailable inhibitor of human immunodeficiency virus type 1 protease with potent antiviral activity.

    Science.gov (United States)

    Alteri, E; Bold, G; Cozens, R; Faessler, A; Klimkait, T; Lang, M; Lazdins, J; Poncioni, B; Roesel, J L; Schneider, P

    1993-10-01

    CGP 53437 is a peptidomimetic inhibitor of human immunodeficiency virus type 1 (HIV-1) protease containing a hydroxyethylene isostere. The compound inhibited recombinant HIV-1 protease with a Ki of 0.2 nM. The inhibition constant versus human cathepsin D and human cathepsin E was 4 nM. Human pepsin and gastricsin were inhibited with Kis of 8 and 500 nM, respectively, and human renin was inhibited with a Ki of 190 microM. The replication of HIV-1/LAV, HIV-1/Z-84, and HIV-1/pLAI was inhibited with a 90% effective dose of 0.1 microM in acutely infected MT-2 cells. The 50% cytotoxic dose was 100 microM. Similar antiviral activity was observed when the compound was added up to 10 h after infection. At the effective concentration, processing of Gag precursor protein p55 was greatly reduced, confirming an action on the late stage of the virus life cycle, as expected. The efficacy of the inhibitor was also demonstrated by using primary human peripheral blood lymphocytes infected with the HIV-1/LAV strain, low-passage clinical isolates obtained from HIV-1-seropositive individuals (including a zidovudine-resistant strain), and HIV-2/ROD. In these cells, CGP 53437 delayed the onset of HIV replication in a dose-dependent fashion (substantial effects with concentrations of > or = 0.1 microM) as long as the inhibitor was maintained in the culture. CGP 53437 was orally bioavailable in mice. Concentrations in plasma 10-fold in excess of the in vitro antiviral 90% effective dose could be sustained for several hours after oral application of 120 mg/kg. Therefore, CGP 53437 has the potential to be a therapeutically useful anti-HIV agent for the treatment of AIDS.

  5. Origin, diversity and maturation of human antiviral antibodies analyzed by high-throughput sequencing

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    Ponraj ePrabakaran

    2012-08-01

    Full Text Available Our understanding of how antibodies are generated and function could help develop effective vaccines and antibody-based therapeutics against viruses such as HIV-1, SARS Coronavirus (CoV, and Hendra and Nipah viruses (henipaviruses. Although broadly neutralizing antibodies (bnAbs against the HIV-1 were observed in patients, elicitation of such bnAbs remains a major challenge when compared to other viral targets. We previously hypothesized that HIV-1 could have evolved a strategy to evade the immune system due to absent or very weak binding of germline antibodies to the conserved epitopes that may not be sufficient to initiate and/or maintain an effective immune response. To further explore our hypothesis, we used the 454 sequence analysis of a large naïve library of human IgM antibodies which had been used for selecting antibodies against SARS Coronavirus (CoV receptor-binding domain (RBD, and soluble G proteins (sG of Hendra and Nipah viruses (henipaviruses. We found that the human IgM repertoires from the 454 sequencing have diverse germline usages, recombination patterns, junction diversity and a lower extent of somatic mutation. In this study, we identified germline intermediates of antibodies specific to HIV-1 and other viruses as observed in normal individuals, and compared their genetic diversity and somatic mutation level along with available structural and functional data. Further computational analysis will provide framework for understanding the underlying genetic and molecular determinants related to maturation pathways of antiviral bnAbs that could be useful for applying novel approaches to the design of effective vaccine immunogens and antibody-based therapeutics.

  6. Independent evolution of Fc- and Fab-mediated HIV-1-specific antiviral antibody activity following acute infection

    Science.gov (United States)

    Dugast, Anne-Sophie; Stamatatos, Leonidas; Tonelli, Andrew; Suscovich, Todd J.; Licht, Anna F.; Mikell, Iliyana; Ackerman, Margaret E.; Streeck, Hendrik; Klasse, P.J.; Moore, John P.; Alter, Galit

    2014-01-01

    Fc-related antibody activities, such as antibody-dependent cellular cytotoxicity (ADCC), or more broadly, antibody-mediated cellular viral inhibition (ADCVI), play a role in curbing early SIV viral replication, are enriched in human long-term infected non-progressors, and could potentially contribute to protection from infection. However, little is known about the mechanism by which such humoral immune responses are naturally induced following infection. Here we focused on the early evolution of the functional antibody response, largely driven by the Fc portion of the antibody, in the context of the evolving binding and neutralizing antibody response, which is driven mainly by the antibody binding fragment (Fab). We show that ADCVI/ADCC-inducing responses in humans are rapidly generated following acute HIV-1 infection, peak at approximately 6 months post-infection, but decay rapidly in the setting of persistent immune activation, as Fab-related activities persistently increase. Moreover, the loss of Fc activity occurred in synchrony with a loss of HIV-specific IgG3 responses. Our data strongly suggest that Fc- and Fab-related antibody functions are modulated in a distinct manner following acute HIV infection. Vaccination strategies intended to optimally induce both sets of antiviral antibody activities may, therefore, require a fine-tuning of the inflammatory response. PMID:25043633

  7. Assorted Processing of Synthetic Trans-Acting siRNAs and Its Activity in Antiviral Resistance.

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    Mingmin Zhao

    Full Text Available The use of syn-tasiRNAs has been proposed as an RNA interference technique alternative to those previously described: hairpin based, virus induced gene silencing or artificial miRNAs. In this study we engineered the TAS1c locus to impair Plum pox virus (PPV infection by replacing the five native siRNAs with two 210-bp fragments from the CP and the 3´NCR regions of the PPV genome. Deep sequencing analysis of the small RNA species produced by both constructs in planta has shown that phased processing of the syn-tasiRNAs is construct-specific. While in syn-tasiR-CP construct the processing was as predicted 21-nt phased in register with miR173-guided cleavage, the processing of syn-tasiR-3NCR is far from what was expected. A 22-nt species from the miR173-guided cleavage was a guide of two series of phased small RNAs, one of them in an exact 21-nt register, and the other one in a mixed of 21-/22-nt frame. In addition, both constructs produced abundant PPV-derived small RNAs in the absence of miR173 as a consequence of a strong sense post-transcriptional gene silencing induction. The antiviral effect of both constructs was also evaluated in the presence or absence of miR173 and showed that the impairment of PPV infection was not significantly higher when miR173 was present. The results show that syn-tasiRNAs processing depends on construct-specific factors that should be further studied before the so-called MIGS (miRNA-induced gene silencing technology can be used reliably.

  8. Assorted Processing of Synthetic Trans-Acting siRNAs and Its Activity in Antiviral Resistance.

    Science.gov (United States)

    Zhao, Mingmin; San León, David; Mesel, Frida; García, Juan Antonio; Simón-Mateo, Carmen

    2015-01-01

    The use of syn-tasiRNAs has been proposed as an RNA interference technique alternative to those previously described: hairpin based, virus induced gene silencing or artificial miRNAs. In this study we engineered the TAS1c locus to impair Plum pox virus (PPV) infection by replacing the five native siRNAs with two 210-bp fragments from the CP and the 3´NCR regions of the PPV genome. Deep sequencing analysis of the small RNA species produced by both constructs in planta has shown that phased processing of the syn-tasiRNAs is construct-specific. While in syn-tasiR-CP construct the processing was as predicted 21-nt phased in register with miR173-guided cleavage, the processing of syn-tasiR-3NCR is far from what was expected. A 22-nt species from the miR173-guided cleavage was a guide of two series of phased small RNAs, one of them in an exact 21-nt register, and the other one in a mixed of 21-/22-nt frame. In addition, both constructs produced abundant PPV-derived small RNAs in the absence of miR173 as a consequence of a strong sense post-transcriptional gene silencing induction. The antiviral effect of both constructs was also evaluated in the presence or absence of miR173 and showed that the impairment of PPV infection was not significantly higher when miR173 was present. The results show that syn-tasiRNAs processing depends on construct-specific factors that should be further studied before the so-called MIGS (miRNA-induced gene silencing) technology can be used reliably.

  9. In vitro antiviral activity of Chamaecrista nictitans (Fabaceae against herpes simplex virus: Biological characterization of mechanisms of action

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    Libia Herrero Uribe

    2004-09-01

    Full Text Available We have previously identified a crude extract of the plant Chamaecrista nictitans (Fabaceaewith antiviral activity against herpes simplex virus.The main objectives of this research were to identify the step of the replication cycle of herpes simplex inhibited by the extract,and to attempt to characterize the chemical characteristics of this extract.The crude extract from Chamaecrista nictitans (Fabaceaewas extracted with a mixture of diclorometane/methanol,and further fractionated following a bioassay-guided protocol using a combination of preparative thin layer and column chromatography.Toxicity and bioassay experiments were carried out in monolayers of Vero cells.The antiviral activity of the extract was assessed by total inhibition of cytopathic effect after three-day incubation.The highest concentration of the extract which was not toxic to the cells was 200 mu g/ml. Western blot and immunofluorescence techniques were used to elucidate the antiviral mechanism of the extract by infecting Vero cells with the virus at different times and monitoring the synthesis of viral proteins.A 60 kDa protein was detected at 2 hr and 8 hr post-infection but no additional proteins were synthesized at later time intervals,and cytopathic effect was not observed after 24 hr.This result indicates that the extract acts at the intracellular level in order to inhibit late transcription.However,it does not inhibit transcription/translation of early viral proteins.These results were confirmed by immunofluorescence experiments.A strong fluorescent signal was observed in control cell monolayers at 24 hr post infection,accompanied with a clear cytopathic effect.In contrast,in the presence of acyclovir or the extract,cells showed very discrete immunofluorescence,characterized by a punctuated pattern, and no cytopathic effect was observed.Neutralization assays were performed using pre-incubation of virus with either specific herpes simplex-1 antiserum,200 mu g/ml of the

  10. A Novel Iminosugar UV-12 with Activity against the Diverse Viruses Influenza and Dengue (Novel Iminosugar Antiviral for Influenza and Dengue).

    Science.gov (United States)

    Warfield, Kelly L; Plummer, Emily; Alonzi, Dominic S; Wolfe, Gary W; Sampath, Aruna; Nguyen, Tam; Butters, Terry D; Enterlein, Sven G; Stavale, Eric J; Shresta, Sujan; Ramstedt, Urban

    2015-05-13

    Iminosugars are capable of targeting the life cycles of multiple viruses by blocking host endoplasmic reticulum α-glucosidase enzymes that are required for competent replication of a variety of enveloped, glycosylated viruses. Iminosugars as a class are approved for use in humans with diseases such as diabetes and Gaucher's disease, providing evidence for safety of this class of compounds. The in vitro antiviral activity of iminosugars has been described in several publications with a subset of these demonstrating in vivo activity against flaviviruses, herpesviruses, retroviruses and filoviruses. Although there is compelling non-clinical in vivo evidence of antiviral efficacy, the efficacy of iminosugars as antivirals has yet to be demonstrated in humans. In the current study, we report a novel iminosugar, UV-12, which has efficacy against dengue and influenza in mouse models. UV-12 exhibits drug-like properties including oral bioavailability and good safety profile in mice and guinea pigs. UV-12 is an example of an iminosugar with activity against multiple virus families that should be investigated in further safety and efficacy studies and demonstrates potential value of this drug class as antiviral therapeutics.

  11. Cissampelos pareira Linn: Natural Source of Potent Antiviral Activity against All Four Dengue Virus Serotypes.

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    Ruchi Sood

    2015-12-01

    Full Text Available Dengue, a mosquito-borne viral disease, poses a significant global public health risk. In tropical countries such as India where periodic dengue outbreaks can be correlated to the high prevalence of the mosquito vector, circulation of all four dengue viruses (DENVs and the high population density, a drug for dengue is being increasingly recognized as an unmet public health need.Using the knowledge of traditional Indian medicine, Ayurveda, we developed a systematic bioassay-guided screening approach to explore the indigenous herbal bio-resource to identify plants with pan-DENV inhibitory activity. Our results show that the alcoholic extract of Cissampelos pariera Linn (Cipa extract was a potent inhibitor of all four DENVs in cell-based assays, assessed in terms of viral NS1 antigen secretion using ELISA, as well as viral replication, based on plaque assays. Virus yield reduction assays showed that Cipa extract could decrease viral titers by an order of magnitude. The extract conferred statistically significant protection against DENV infection using the AG129 mouse model. A preliminary evaluation of the clinical relevance of Cipa extract showed that it had no adverse effects on platelet counts and RBC viability. In addition to inherent antipyretic activity in Wistar rats, it possessed the ability to down-regulate the production of TNF-α, a cytokine implicated in severe dengue disease. Importantly, it showed no evidence of toxicity in Wistar rats, when administered at doses as high as 2g/Kg body weight for up to 1 week.Our findings above, taken in the context of the human safety of Cipa, based on its use in Indian traditional medicine, warrant further work to explore Cipa as a source for the development of an inexpensive herbal formulation for dengue therapy. This may be of practical relevance to a dengue-endemic resource-poor country such as India.

  12. Screening bioactives reveals nanchangmycin as a broad spectrum antiviral active against Zika virus

    Science.gov (United States)

    Rausch, Keiko; Hackett, Brent; Weinbren, Nathan; Reeder, Sophia; Sadovsky, Yoel; Hunter, Christopher; Schultz, David C.; Coyne, Carolyn; Cherry, Sara

    2017-01-01

    Zika virus is an emerging arthropod-borne flavivirus for which there are no vaccines or specific therapeutics. We screened a library of 2000 ‘bioactive’ compounds for their ability to block Zika virus infection in three distinct cell-types with two different strains of Zika virus. Using a microscopy-based assay, we validated 38 drugs that inhibited Zika virus infection, including FDA approved nucleoside analogs. Cells expressing high levels of the attachment factor AXL can be protected from infection with receptor tyrosine kinase inhibitors, while placental-derived cells that lack AXL expression are insensitive to this inhibition. Importantly, we identified nanchangmycin as a potent inhibitor of Zika virus entry across all cell types tested including physiologically relevant primary cells. Nanchanmycin was also active against other medically relevant viruses including West Nile, dengue, and chikungunya virus that use a similar route of entry. This study provides a resource of small molecules to study Zika virus pathogenesis. PMID:28099856

  13. Novel antiviral activity of neuraminidase inhibitors against an avian influenza a virus

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    Ohuchi Masanobu

    2011-08-01

    Full Text Available Abstract Background Neuraminidase (NA inhibitors used for influenza therapy are believed to prevent the release of progeny virus from the surface of an infected cell. In this study, we found that NA inhibitors have a novel antiviral function against an avian influenza virus. Results Madin-Darby canine kidney cells, commonly used for the isolation and propagation of the influenza virus, were infected with an avian influenza viral strain A/chicken/German/N/49(H10N7 (H10/chicken or a human influenza viral strain A/Osaka/981/98(H3N2 (H3/Osaka virus. Cells were incubated in a medium without or with a NA inhibitor, oseltamivir carboxylate (GS4071, from 1 to 13 h post infection (p.i.. Infected cells were washed 12 h p.i. to remove GS4071, incubated for 1 h without GS4071, and assayed for virus production. Incubation with GS4071 decreased the production of infectious viruses. When H10/chicken virus-infected cells were incubated with GS4071 from 12 to 13 h p.i. (i.e., 1 h before the virus production assay, the inhibitory effect was clearly observed, however, the same was not evident for H3/Osaka virus-infected cells. Furthermore, viral protein synthesis in infected cells was not affected by GS4071. Using a scanning electron microscope, many single spherical buds were observed on the surface of H3/Osaka virus-infected cells incubated without GS4071, whereas many aggregated particles were observed on the surface of cells incubated with GS4071. However, many long tubular virus-like structures, with no aggregated particles, were observed on the surface of H10/chicken virus-infected cells incubated with GS4071. The same results were obtained when another NA inhibitor, zanamivir, was used. Conclusions These results indicate that NA inhibitors interfered with virus particle formation in the H10/chicken virus-infected cells, in which the inhibitor caused the formation of long tubular virus-like structures instead of spherical virus particles.

  14. Cross-Species Antiviral Activity of Goose Interferons against Duck Plague Virus Is Related to Its Positive Self-Feedback Regulation and Subsequent Interferon Stimulated Genes Induction.

    Science.gov (United States)

    Zhou, Hao; Chen, Shun; Zhou, Qin; Wei, Yunan; Wang, Mingshu; Jia, Renyong; Zhu, Dekang; Liu, Mafeng; Liu, Fei; Yang, Qiao; Wu, Ying; Sun, Kunfeng; Chen, Xiaoyue; Cheng, Anchun

    2016-01-01

    Interferons are a group of antiviral cytokines acting as the first line of defense in the antiviral immunity. Here, we describe the antiviral activity of goose type I interferon (IFNα) and type II interferon (IFNγ) against duck plague virus (DPV). Recombinant goose IFNα and IFNγ proteins of approximately 20 kDa and 18 kDa, respectively, were expressed. Following DPV-enhanced green fluorescent protein (EGFP) infection of duck embryo fibroblast cells (DEFs) with IFNα and IFNγ pre-treatment, the number of viral gene copies decreased more than 100-fold, with viral titers dropping approximately 100-fold. Compared to the control, DPV-EGFP cell positivity was decreased by goose IFNα and IFNγ at 36 hpi (3.89%; 0.79%) and 48 hpi (17.05%; 5.58%). In accordance with interferon-stimulated genes being the "workhorse" of IFN activity, the expression of duck myxovirus resistance (Mx) and oligoadenylate synthetases-like (OASL) was significantly upregulated (p interferon. These findings will contribute to our understanding of the functional significance of the interferon antiviral system in aquatic birds and to the development of interferon-based prophylactic and therapeutic approaches against viral disease.

  15. The effect of antiviral activity of a green seaweed from the Persian Gulf, Caulerpa sertularioides on Herpes Simplex Virus Type 1

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    Keyvan Zandi

    2006-09-01

    Full Text Available Background: By considering the daily increase in drug resistance of various viruses, novel antiviral compounds extracted from natural resources – due to their fewer side effects, had always been important to researchers. In the present study, we investigated antiviral activity of the hot water extract of a green seaweed, Caulerpa sertularioides, collected from coastal water of Bushehr in the Persian Gulf, against Herpes Simplex Virus Type 1 (HSV-1. Methods: The hot water extract of a green seaweed, Caulerpa sertularioides was sterilized by autoclave and filtration methods. After determining its cytotoxic concentration 50 (CC50 value, the effect of the extract on the inhibition of HSV-1 replication was examined in Vero cell culture. Results: The extract showed antiviral activity against HSV-1 in both attachment and entry of virus to the Vero cells and also on post attachment stages of virus replication. Inhibitory concentration 50 (IC50 values of the autoclaved extract were 81µg/ml and 126 µg/ml for attachment and post attachment stages, respectively. IC50 values of the filtered extract were 73 µg/ml and 104 µg/ml for attachment and post attachment stages, respectively. CC50 values for autoclaved and filtered extracts were 3140 µg/ml and 3095 µg/ml, respectively. Conclusion: The hot water extract of Caulerpa sertularioides of the Persian Gulf had antiviral effect against HSV-1.

  16. Hydantoin derivatives of L- and D-amino acids: synthesis and evaluation of their antiviral and antitumoral activity.

    Science.gov (United States)

    Rajic, Zrinka; Zorc, Branka; Raic-Malic, Silvana; Ester, Katja; Kralj, Marijeta; Pavelic, Kresimir; Balzarini, Jan; De Clercq, Erik; Mintas, Mladen

    2006-11-01

    3,5-Disubstituted hydantoin (1,3-imidazolidinedione) derivatives 5a-h were prepared by base induced cyclization of the corresponding N-(1-benzotriazolecarbonyl)-L- and D-amino acid amides 4a-h. Compounds 5a-h were evaluated for their cytostatic and antiviral activities. Among all the compounds evaluated, 3-benzhydryl-5-isopropyl hydantoin (5a) showed a weak but selective inhibitory effect against vaccinia virus (EC(50) = 16 microg/mL; selectivity index: 25). 3-Cyclohexyl-5-phenyl hydantoin (5g) showed inhibitory activity against cervical carcinoma (HeLa, IC(50) = 5.4 microM) and breast carcinoma (MCF-7, IC(50) = 2 microM), but also cytotoxic effects towards human normal fibroblasts (WI 38). On the contrary, the 3-benzhydryl-5-phenyl substituted hydantoin derivative 5h showed moderate inhibitory activity towards HeLa, MCF-7, pancreatic carcinoma (MiaPaCa-2), lung carcinoma (H 460) and colon carcinoma (SW 620) (IC(50) = 20-23 microM), but no effect on WI 38.

  17. Structure-assisted design of mechanism-based irreversible inhibitors of human rhinovirus 3C protease with potent antiviral activity against multiple rhinovirus serotypes.

    Science.gov (United States)

    Matthews, D A; Dragovich, P S; Webber, S E; Fuhrman, S A; Patick, A K; Zalman, L S; Hendrickson, T F; Love, R A; Prins, T J; Marakovits, J T; Zhou, R; Tikhe, J; Ford, C E; Meador, J W; Ferre, R A; Brown, E L; Binford, S L; Brothers, M A; DeLisle, D M; Worland, S T

    1999-09-28

    Human rhinoviruses, the most important etiologic agents of the common cold, are messenger-active single-stranded monocistronic RNA viruses that have evolved a highly complex cascade of proteolytic processing events to control viral gene expression and replication. Most maturation cleavages within the precursor polyprotein are mediated by rhinovirus 3C protease (or its immediate precursor, 3CD), a cysteine protease with a trypsin-like polypeptide fold. High-resolution crystal structures of the enzyme from three viral serotypes have been used for the design and elaboration of 3C protease inhibitors representing different structural and chemical classes. Inhibitors having alpha,beta-unsaturated carbonyl groups combined with peptidyl-binding elements specific for 3C protease undergo a Michael reaction mediated by nucleophilic addition of the enzyme's catalytic Cys-147, resulting in covalent-bond formation and irreversible inactivation of the viral protease. Direct inhibition of 3C proteolytic activity in virally infected cells treated with these compounds can be inferred from dose-dependent accumulations of viral precursor polyproteins as determined by SDS/PAGE analysis of radiolabeled proteins. Cocrystal-structure-assisted optimization of 3C-protease-directed Michael acceptors has yielded molecules having extremely rapid in vitro inactivation of the viral protease, potent antiviral activity against multiple rhinovirus serotypes and low cellular toxicity. Recently, one compound in this series, AG7088, has entered clinical trials.

  18. Antiviral biflavonoids from Radix Wikstroemiae (Liaogewanggen

    Directory of Open Access Journals (Sweden)

    Ye Wencai

    2010-06-01

    Full Text Available Abstract Background Radix Wikstroemiae is a common Chinese herbal medicine. The ethyl acetate fraction of the ethanolic extract of W. indica possesses potent in vitro antiviral activity against respiratory syncytial virus (RSV. This study aims to identify the antiviral components of the active fraction. Methods The active fraction of the Radix Wikstroemiae extract was isolated with chromatographic methods such as silica gel, Sephadex LH-20 and semi-preparative high performance liquid chromatography (HPLC columns. The structures of the isolated compounds were determined based on spectroscopic analyses. The in vitro antiviral activity of the compounds against RSV was tested with the cytopathic effect (CPE reduction assay and the 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide (MTT method. Results Four biflavonoids, namely neochamaejasmin B, genkwanol B, genkwanol C and stelleranol, were isolated and characterized. Genkwanol B, genkwanol C and stelleranol, which are stereo isomers of spirobiflavonoids, showed potent anti-RSV activity whereas neochamaejasmin B did not. Conclusion Neochamaejasmin B, genkwanol B, genkwanol C and stelleranol were isolated from Radix Wikstroemiae and the complete absolute configurations of five chiral carbons in stelleranol were substantiated for the first time. Furthermore, the anti-RSV activity of genkwanol B, genkwanol C and stelleranol was reported for the first time.

  19. Broad-spectrum antiviral therapeutics.

    Directory of Open Access Journals (Sweden)

    Todd H Rider

    Full Text Available Currently there are relatively few antiviral therapeutics, and most which do exist are highly pathogen-specific or have other disadvantages. We have developed a new broad-spectrum antiviral approach, dubbed Double-stranded RNA (dsRNA Activated Caspase Oligomerizer (DRACO that selectively induces apoptosis in cells containing viral dsRNA, rapidly killing infected cells without harming uninfected cells. We have created DRACOs and shown that they are nontoxic in 11 mammalian cell types and effective against 15 different viruses, including dengue flavivirus, Amapari and Tacaribe arenaviruses, Guama bunyavirus, and H1N1 influenza. We have also demonstrated that DRACOs can rescue mice challenged with H1N1 influenza. DRACOs have the potential to be effective therapeutics or prophylactics for numerous clinical and priority viruses, due to the broad-spectrum sensitivity of the dsRNA detection domain, the potent activity of the apoptosis induction domain, and the novel direct linkage between the two which viruses have never encountered.

  20. Kronik Hepatit B'li Gebelerde Uygulanan Antiviral Tedavi Sonuçlarinin Degerlendirilmesi

    National Research Council Canada - National Science Library

    Ayse ERTÜRK; Ekan CÜRE; Emine PARLAK; Medine Cumhur CÜRE; Aysegül ÇAPUR ÇIÇEK; Figen KIR SAHIN

    2014-01-01

    .... It is possible to prevent transmission with antiviral treatment performed in pregnant women with high viral load in adition to the passive and active immunization treatment performed in the infant...

  1. Antiviral Activity of Bacillus sp. Isolated from the Marine Sponge Petromica citrina against Bovine Viral Diarrhea Virus, a Surrogate Model of the Hepatitis C Virus

    Science.gov (United States)

    Bastos, Juliana Cristina Santiago; Kohn, Luciana Konecny; Fantinatti-Garboggini, Fabiana; Padilla, Marina Aiello; Flores, Eduardo Furtado; da Silva, Bárbara Pereira; de Menezes, Cláudia Beatriz Afonso; Arns, Clarice Weis

    2013-01-01

    The Hepatitis C virus causes chronic infections in humans, which can develop to liver cirrhosis and hepatocellular carcinoma. The Bovine viral diarrhea virus is used as a surrogate model for antiviral assays for the HCV. From marine invertebrates and microorganisms isolated from them, extracts were prepared for assessment of their possible antiviral activity. Of the 128 tested, 2 were considered active and 1 was considered promising. The best result was obtained from the extracts produced from the Bacillus sp. isolated from the sponge Petromica citrina. The extracts 555 (500 µg/mL, SI>18) and 584 (150 µg/mL, SI 27) showed a percentage of protection of 98% against BVDV, and the extract 616, 90% of protection. All of them showed activity during the viral adsorption. Thus, various substances are active on these studied organisms and may lead to the development of drugs which ensure an alternative therapy for the treatment of hepatitis C. PMID:23628828

  2. Antiviral Activity of Bacillus sp. Isolated from the Marine Sponge Petromica citrina against Bovine Viral Diarrhea Virus, a Surrogate Model of the Hepatitis C Virus

    Directory of Open Access Journals (Sweden)

    Clarice Weis Arns

    2013-04-01

    Full Text Available The Hepatitis C virus causes chronic infections in humans, which can develop to liver cirrhosis and hepatocellular carcinoma. The Bovine viral diarrhea virus is used as a surrogate model for antiviral assays for the HCV. From marine invertebrates and microorganisms isolated from them, extracts were prepared for assessment of their possible antiviral activity. Of the 128 tested, 2 were considered active and 1 was considered promising. The best result was obtained from the extracts produced from the Bacillus sp. isolated from the sponge Petromica citrina. The extracts 555 (500 µg/mL, SI>18 and 584 (150 µg/mL, SI 27 showed a percentage of protection of 98% against BVDV, and the extract 616, 90% of protection. All of them showed activity during the viral adsorption. Thus, various substances are active on these studied organisms and may lead to the development of drugs which ensure an alternative therapy for the treatment of hepatitis C.

  3. Isolation and antiviral activity of water-soluble Cynomorium songaricum Rupr. polysaccharides.

    Science.gov (United States)

    Tuvaanjav, Suvdmaa; Shuqin, Han; Komata, Masashi; Ma, Chunjie; Kanamoto, Taisei; Nakashima, Hideki; Yoshida, Takashi

    2016-01-01

    The plant, Cynomorium songaricum Rupr., is used as a traditional medicine in China and Mongolia. In the present study, two new water-soluble polysaccharides isolated from C. songaricum Rupr. were purified by successive Sephadex G-75 and G-50 column chromatographies and then characterized by high resolution NMR and IR spectroscopies. The molecular weights of two polysaccharides were determined by an aqueous GPC to be [Formula: see text] = 3.7 × 10(4) and 1.0 × 10(4), respectively. In addition, it was found that the polysaccharide with the larger molecular weight was an acidic polysaccharide. It was found that the iodine-starch reaction of both isolated polysaccharides was negative and the methylation analysis gave 2, 4, 6-tri-O-methyl alditol acetate as a main product. NMR and IR measurements and sugar analysis revealed that both polysaccharides had a (1 → 3)-α-d-glucopyranosidic main chain with a small number of branches. After sulfation, the sulfated C. songaricum Rupr. polysaccharides were found to have a potent inhibitory effect on HIV infection of MT-4 cells at a 50% effective concentration of 0.3-0.4 μg/ml, a concentration that has almost the same high activity as standard dextran and curdlan sulfates, EC50 = 0.35 and 0.14 μg/ml, respectively. The 50% cytotoxic concentration was low, CC50>1000 μg/ml. In addition, the interaction between the sulfated polysaccharides and poly-l-lysine as a model protein compound was investigated by a surface plasmon resonance to reveal the anti-HIV mechanism.

  4. High-throughput screening normalized to biological response: application to antiviral drug discovery.

    Science.gov (United States)

    Patel, Dhara A; Patel, Anand C; Nolan, William C; Huang, Guangming; Romero, Arthur G; Charlton, Nichole; Agapov, Eugene; Zhang, Yong; Holtzman, Michael J

    2014-01-01

    The process of conducting cell-based phenotypic screens can result in data sets from small libraries or portions of large libraries, making accurate hit picking from multiple data sets important for efficient drug discovery. Here, we describe a screen design and data analysis approach that allow for normalization not only between quadrants and plates but also between screens or batches in a robust, quantitative fashion, enabling hit selection from multiple data sets. We independently screened the MicroSource Spectrum and NCI Diversity Set II libraries using a cell-based phenotypic high-throughput screening (HTS) assay that uses an interferon-stimulated response element (ISRE)-driven luciferase-reporter assay to identify interferon (IFN) signal enhancers. Inclusion of a per-plate, per-quadrant IFN dose-response standard curve enabled conversion of ISRE activity to effective IFN concentrations. We identified 45 hits based on a combined z score ≥2.5 from the two libraries, and 25 of 35 available hits were validated in a compound concentration-response assay when tested using fresh compound. The results provide a basis for further analysis of chemical structure in relation to biological function. Together, the results establish an HTS method that can be extended to screening for any class of compounds that influence a quantifiable biological response for which a standard is available.

  5. Study on Antimicrobial and Antiviral Activities of Lysozyme From Marine Strain S-12-86 In Vitro

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    In this study, the in vitro antimicrobial and antiviral activities of the lysozyme from marine strain S-12-86 (LS) were investigated. The antimicrobial activity of LS was tested by minimum inhibition concentration (MIC) and minimum bactericidal concentration (MBC) method. The inhibiting effects of LS on pseudo rabies virus (PRV) in swine kidney cells (PK-15 cells) were judged by cytopathogenic effect test (CPE). The results showed LS had a broad antimicrobial spectrum against several standard strains including gram-positive bacteria, gram-negative bacteria, fungi, etc. The MIC of LS was 0.25-4.00 mg mL-1 and its MBC was 0.25-8.00 mg mL-1, respectively. Observation under the transmission electron microscope revealed that the cell wall of Candida albicans was distorted seriously, and the cytoplasm with many cavities was asymmetrical after being hydrolyzed by LS. The median cytotoxicity concentration (TC50) of LS was 100.0 μg mL-1, the median effective concentration (EC50) was 0.46 μg mL-1, and the selectivity index (TI = TC50/EC50) was 217. LS could inhibit PRV in PK-15 cells when it was added to cell culture medium at 0, 2, 4, 6, and 8 h after PK-15 cells had been infected by PRV. From the results, we concluded that LS had broad antimicrobial spectrum and good inhibiting effects on PRV.

  6. Multiple interferon stimulated genes synergize with the zinc finger antiviral protein to mediate anti-alphavirus activity.

    Directory of Open Access Journals (Sweden)

    Sophiya Karki

    Full Text Available The zinc finger antiviral protein (ZAP is a host factor that mediates inhibition of viruses in the Filoviridae, Retroviridae and Togaviridae families. We previously demonstrated that ZAP blocks replication of Sindbis virus (SINV, the prototype Alphavirus in the Togaviridae family at an early step prior to translation of the incoming genome and that synergy between ZAP and one or more interferon stimulated genes (ISGs resulted in maximal inhibitory activity. The present study aimed to identify those ISGs that synergize with ZAP to mediate Alphavirus inhibition. Using a library of lentiviruses individually expressing more than 350 ISGs, we screened for inhibitory activity in interferon defective cells with or without ZAP overexpression. Confirmatory tests of the 23 ISGs demonstrating the largest infection reduction in combination with ZAP revealed that 16 were synergistic. Confirmatory tests of all potentially synergistic ISGs revealed 15 additional ISGs with a statistically significant synergistic effect in combination with ZAP. These 31 ISGs are candidates for further mechanistic studies. The number and diversity of the identified ZAP-synergistic ISGs lead us to speculate that ZAP may play an important role in priming the cell for optimal ISG function.

  7. Multiple interferon stimulated genes synergize with the zinc finger antiviral protein to mediate anti-alphavirus activity.

    Science.gov (United States)

    Karki, Sophiya; Li, Melody M H; Schoggins, John W; Tian, Suyan; Rice, Charles M; MacDonald, Margaret R

    2012-01-01

    The zinc finger antiviral protein (ZAP) is a host factor that mediates inhibition of viruses in the Filoviridae, Retroviridae and Togaviridae families. We previously demonstrated that ZAP blocks replication of Sindbis virus (SINV), the prototype Alphavirus in the Togaviridae family at an early step prior to translation of the incoming genome and that synergy between ZAP and one or more interferon stimulated genes (ISGs) resulted in maximal inhibitory activity. The present study aimed to identify those ISGs that synergize with ZAP to mediate Alphavirus inhibition. Using a library of lentiviruses individually expressing more than 350 ISGs, we screened for inhibitory activity in interferon defective cells with or without ZAP overexpression. Confirmatory tests of the 23 ISGs demonstrating the largest infection reduction in combination with ZAP revealed that 16 were synergistic. Confirmatory tests of all potentially synergistic ISGs revealed 15 additional ISGs with a statistically significant synergistic effect in combination with ZAP. These 31 ISGs are candidates for further mechanistic studies. The number and diversity of the identified ZAP-synergistic ISGs lead us to speculate that ZAP may play an important role in priming the cell for optimal ISG function.

  8. Synthesis and hepatitis C antiviral activity of 1-aminobenzyl-1H-indazole-3-carboxamide analogues.

    Science.gov (United States)

    Shi, Jing-Jing; Ji, Fei-Hong; He, Pei-Lan; Yang, Ya-xi; Tang, Wei; Zuo, Jian-Ping; Li, Yuan-Chao

    2013-05-01

    FIGHTING HCV: Two potent antiviral analogues were developed from a previously identified lead as novel agents against hepatitis C virus. Their potency and selectivity (5 n: IC50 =0.013 μM and EC50 =0.018 μM; 5 t: IC50 =0.007 μM and EC50 =0.024 μM) make them good candidates for further development as antiviral agents.

  9. Synthesis and Antiviral Activity of Novel 1,4-Pentadien-3-one Derivatives Containing a 1,3,4-Thiadiazole Moiety

    Directory of Open Access Journals (Sweden)

    Lu Yu

    2017-04-01

    Full Text Available 1,4-Pentadien-3-one derivatives derived from curcumin possess excellent inhibitory activity against plant viruses. On the basis of this finding, a series of novel 1,4-pentadien-3-one derivatives containing a 1,3,4-thiadiazole moiety were designed and synthesized, and their structures confirmed by IR, 1H-NMR, and 13C-NMR spectroscopy and elemental analysis. The antiviral activities of the title compounds were evaluated against tobacco mosaic virus (TMV and cucumber mosaic virus (CMV in vivo. The assay results showed that most of compounds had remarkable antiviral activities against TMV and CMV, among which compounds 4b, 4h, 4i, 4k, 4o, and 4q exhibited good curative, protection, and inactivation activity against TMV. Compounds 4h, 4i, 4k, 4l, 4o, and 4q exhibited excellent protection activity against TMV, with EC50 values of 105.01, 254.77, 135.38, 297.40, 248.18, and 129.87 μg/mL, respectively, which were superior to that of ribavirin (457.25 µg/mL. In addition, preliminary SARs indicated that small electron-withdrawing groups on the aromatic ring were favorable for anti-TMV activity. This finding suggests that 1,4-pentadien-3-one derivatives containing a 1,3,4-thiadiazole moiety may be considered as potential lead structures for discovering new antiviral agents.

  10. Copper(II) complexes with new fluoroquinolones: Synthesis, structure, spectroscopic and theoretical study, DNA damage, cytotoxicity and antiviral activity.

    Science.gov (United States)

    Dorotíková, Sandra; Kožíšková, Júlia; Malček, Michal; Jomová, Klaudia; Herich, Peter; Plevová, Kristína; Briestenská, Katarína; Chalupková, Anna; Mistríková, Jela; Milata, Viktor; Dvoranová, Dana; Bučinský, Lukáš

    2015-09-01

    Copper(II) complexes with fluoroquinolones in the presence of the nitrogen donor heterocyclic ligands 1,10-phenanthroline have been considered in detail. The phenanthroline moiety was introduced into the ligand environment with the aim to determine whether the nuclease activity is feasible. All suitable X-ray structures of the complexes under study reveal a distorted square pyramidal coordination geometry for Cu(II) atom. The conformational and spectroscopic (FT-IR and UV-visible) behavior has been analyzed and has been interpreted with respect to B3LYP/6-311G* calculations including molecular dynamics. The ability of the complexes to cleave DNA was studied by agarose gel electrophoresis with plasmid DNA pBSK+. The results have confirmed that the complexes under study behave as the chemical nucleases. Nuclease like activity in the absence of hydrogen peroxide allows us to deduce an interaction of the complexes with the DNA resulting in the conversion of supercoiled circular DNA to the nicked form. The DNA cleavage activity enhanced by the presence of hydrogen peroxide demonstrates the participation of reactive oxygen species, such as superoxide radical anions and hydroxyl radicals which presence was confirmed independently using the standard radical scavenging agents. It has been suggested that the radical formation through the Fenton/Haber-Weiss reaction is mediated by the redox cycling mechanisms with the participation of cupric/cuprous ions. Cytotoxic activity was evaluated as the 50% cytotoxic concentration (CC50). The potential effects of tested compounds on replication of murine gammaherpesvirus 68 (MHV-68) under in vitro conditions were also evaluated. However, no antiviral activity against MHV-68 was observed. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. Possible role of phosphoinositide-3-kinase in Mx1 protein translation and antiviral activity of interferon-omega-stimulated HeLa cells.

    Science.gov (United States)

    Seo, Youngjun; Kim, Mihee; Choi, Minjoung; Kim, Sunhee; Park, Kidae; Oh, Ilung; Chung, Seungtae; Suh, Hongwon; Hong, Seunghwa; Park, Suenie

    2011-01-01

    Interferon ω (IFN-ω), a cytokine released during innate immune activation, is well known for promoting direct antiviral responses; however, the possible signal pathways that are initiated by IFN-ω binding to the type I IFN receptors have not been fully studied. Here, we provide evidence that activation of phosphoinositide-3-kinase/protein kinase B (PI3K/Akt) signaling plays a pivotal role in the generation of IFN-ω-mediated biological responses. We found that LY294002 (PI3K inhibitor)-attenuated antiviral activities are induced by IFN-ω treatment. Although such effects of LY294002 are unrelated to regulatory activities on IFN-ω-dependent Mx1 (myxovirus resistance 1) or Mx2 gene transcriptional regulation, translation of Mx1 protein, which was known as a key mediator of cell-autonomous antiviral resistance, was significantly reduced by PI3K inhibition. Further studies showed that PI3K inhibition using LY294002 leads to a decrease in PI3K substrate Akt and mitogen-activated protein kinase extracellular signal-regulated kinase and p38 phosphorylation/activation. In addition, although LY294002 was not able to reduce STAT1 activation, we found that the mammalian target of rapamycin (mTOR)/p70 S6 kinase pathway was significantly attenuated by inhibition of the PI3K/Akt signaling pathway. These results indicate that the PI3K/Akt pathway is a common and central integrator for antiviral responses in IFN-ω signaling via its regulatory effects on mTOR that are required for initiation of mRNA translation of Mx genes.

  12. Mytilus galloprovincialis myticin C: a chemotactic molecule with antiviral activity and immunoregulatory properties.

    Science.gov (United States)

    Balseiro, Pablo; Falcó, Alberto; Romero, Alejandro; Dios, Sonia; Martínez-López, Alicia; Figueras, Antonio; Estepa, Amparo; Novoa, Beatriz

    2011-01-01

    Previous research has shown that an antimicrobial peptide (AMP) of the myticin class C (Myt C) is the most abundantly expressed gene in cDNA and suppressive subtractive hybridization (SSH) libraries after immune stimulation of mussel Mytilus galloprovincialis. However, to date, the expression pattern, the antimicrobial activities and the immunomodulatory properties of the Myt C peptide have not been determined. In contrast, it is known that Myt C mRNA presents an unusual and high level of polymorphism of unidentified biological significance. Therefore, to provide a better understanding of the features of this interesting molecule, we have investigated its function using four different cloned and expressed variants of Myt C cDNA and polyclonal anti-Myt C sera. The in vivo results suggest that this AMP, mainly present in hemocytes, could be acting as an immune system modulator molecule because its overexpression was able to alter the expression of mussel immune-related genes (as the antimicrobial peptides Myticin B and Mytilin B, the C1q domain-containing protein MgC1q, and lysozyme). Moreover, the in vitro results indicate that Myt C peptides have antimicrobial and chemotactic properties. Their recombinant expression in a fish cell line conferred protection against two different fish viruses (enveloped and non-enveloped). Cell extracts from Myt C expressing fish cells were also able to attract hemocytes. All together, these results suggest that Myt C should be considered not only as an AMP but also as the first chemokine/cytokine-like molecule identified in bivalves and one of the few examples in all of the invertebrates.

  13. Mytilus galloprovincialis myticin C: a chemotactic molecule with antiviral activity and immunoregulatory properties.

    Directory of Open Access Journals (Sweden)

    Pablo Balseiro

    Full Text Available Previous research has shown that an antimicrobial peptide (AMP of the myticin class C (Myt C is the most abundantly expressed gene in cDNA and suppressive subtractive hybridization (SSH libraries after immune stimulation of mussel Mytilus galloprovincialis. However, to date, the expression pattern, the antimicrobial activities and the immunomodulatory properties of the Myt C peptide have not been determined. In contrast, it is known that Myt C mRNA presents an unusual and high level of polymorphism of unidentified biological significance. Therefore, to provide a better understanding of the features of this interesting molecule, we have investigated its function using four different cloned and expressed variants of Myt C cDNA and polyclonal anti-Myt C sera. The in vivo results suggest that this AMP, mainly present in hemocytes, could be acting as an immune system modulator molecule because its overexpression was able to alter the expression of mussel immune-related genes (as the antimicrobial peptides Myticin B and Mytilin B, the C1q domain-containing protein MgC1q, and lysozyme. Moreover, the in vitro results indicate that Myt C peptides have antimicrobial and chemotactic properties. Their recombinant expression in a fish cell line conferred protection against two different fish viruses (enveloped and non-enveloped. Cell extracts from Myt C expressing fish cells were also able to attract hemocytes. All together, these results suggest that Myt C should be considered not only as an AMP but also as the first chemokine/cytokine-like molecule identified in bivalves and one of the few examples in all of the invertebrates.

  14. Antiviral and anti-inflammatory activity of arbidol hydrochloride in influenza A (H1N1) virus infection

    Institute of Scientific and Technical Information of China (English)

    Qiang LIU; Hai-rong XIONG; Li LU; Yuan-yuan LIU; Fan LUO; Wei HOU; Zhan-qiu YANG

    2013-01-01

    Aim:To investigate the effects of arbidol hydrochloride (ARB),a widely used antiviral agent,on the inflammation induced by influenza virus.Methods:MDCK cells were infected with seasonal influenza A/FM/1/47 (H1N1) or pandemic influenza A/Hubei/71/2009 (H1N1).In vitro cytotoxicity and antiviral activity of ARB was determined using MTT assay.BALB/c mice were infected with A/FM/1/47 (H1N1).Four hours later the mice were administered ARB (45,90,and 180 mg·kg-1·d-1) or the neuraminidase inhibitor oseltamivir (22.5mg·kg-1·d-1) via oral gavage once a day for 5 d.Body-weight,median survival time,viral titer,and lung index of the mice were measured.The levels of inflammatory cytokines were examined using real-time RT-PCR and ELISA.Results:Both H1N1 stains were equally sensitive to ARB as tested in vitro.In the infected mice,ARB (90 and 180 mg·kg-1·d-1)significantly decreased the mortality,alleviated virus-induced lung lesions and viral titers.Furthermore,ARB suppressed the levels of IL-1β,IL-6,IL-12,and TNF-α,and elevated the level of IL-10 in the bronchoalveolar lavage fluids and lung tissues.However,ARB did not significantly affect the levels of IFN-α and IFN-γ,but reduced the level of IFN-β1 in lung tissues at 5 dpi.In peritoneal macrophages challenged with A/FM/1/47 (H1N1) or poly I∶C,ARB (20 μmol/L) suppressed the levels of IL-1β,IL-6,IL-12,and TNF-α,and elevated the level of IL-10.Oseltamivir produced comparable alleviation of virus-induced lung lesions with more reduction in the viral titers,but less effective modulation of the inflammatory cytokines.Conclusion:ARB efficiently inhibits both H1N1 stains and diminishes both viral replication and acute inflammation through modulating the expression of inflammatory cytokines.

  15. Synthesis and antiviral activity of new dimeric inhibitors against HIV-1

    DEFF Research Database (Denmark)

    Danel, Krzysztof; Larsen, Louise M.; Pedersen, Erik Bjerreg.

    2008-01-01

    by Sonogashira reaction, ‘click' chemistry or Pd-catalyzed oxidative coupling. The iodo precursor 5 turned out as a potent compound against wild type and mutated HIV-1 virus. All dimeric compounds showed lower activity against HIV-1 than MKC-442, except the asymmetric dimer of AZT and 1a which showed an activity...

  16. Computer-aided identification, design and synthesis of a novel series of compounds with selective antiviral activity against chikungunya virus.

    Science.gov (United States)

    Bassetto, Marcella; De Burghgraeve, Tine; Delang, Leen; Massarotti, Alberto; Coluccia, Antonio; Zonta, Nicola; Gatti, Valerio; Colombano, Giampiero; Sorba, Giovanni; Silvestri, Romano; Tron, Gian Cesare; Neyts, Johan; Leyssen, Pieter; Brancale, Andrea

    2013-04-01

    Chikungunya virus (CHIKV) is an Arbovirus that is transmitted to humans primarily by the mosquito species Aedes aegypti. Infection with this pathogen is often associated with fever, rash and arthralgia. Neither a vaccine nor an antiviral drug is available for the prevention or treatment of this disease. Albeit considered a tropical pathogen, adaptation of the virus to the mosquito species Aedes albopictus, which is also very common in temperate zones, has resulted in recent outbreaks in Europe and the US. In the present study, we report on the discovery of a novel series of compounds that inhibit CHIKV replication in the low μM range. In particular, we initially performed a virtual screening simulation of ∼5 million compounds on the CHIKV nsP2, the viral protease, after which we investigated and explored the Structure-Activity Relationships of the hit identified in silico. Overall, a series of 26 compounds, including the original hit, was evaluated in a virus-cell-based CPE reduction assay. The study of such selective inhibitors will contribute to a better understanding of the CHIKV replication cycle and may represents a first step towards the development of a clinical candidate drug for the treatment of this disease.

  17. MEK/ERK activation plays a decisive role in yellow fever virus replication: implication as an antiviral therapeutic target.

    Science.gov (United States)

    Albarnaz, Jonas D; De Oliveira, Leonardo C; Torres, Alice A; Palhares, Rafael M; Casteluber, Marisa C; Rodrigues, Claudiney M; Cardozo, Pablo L; De Souza, Aryádina M R; Pacca, Carolina C; Ferreira, Paulo C P; Kroon, Erna G; Nogueira, Maurício L; Bonjardim, Cláudio A

    2014-11-01

    Exploiting the inhibition of host signaling pathways aiming for discovery of potential antiflaviviral compounds is clearly a beneficial strategy for the control of life-threatening diseases caused by flaviviruses. Here we describe the antiviral activity of the MEK1/2 inhibitor U0126 against Yellow fever virus 17D vaccine strain (YFV-17D). Infection of VERO cells with YFV-17D stimulates ERK1/2 phosphorylation early during infection. Pharmacological inhibition of MEK1/2 through U0126 treatment of VERO cells blockades not only the YFV-stimulated ERK1/2 phosphorylation, but also inhibits YFV replication by ∼99%. U0126 was also effective against dengue virus (DENV-2 and -3) and Saint-Louis encephalitis virus (SLEV). Levels of NS4AB, as detected by immunofluorescence, are diminished upon treatment with the inhibitor, as well as the characteristic endoplasmic reticulum membrane invagination stimulated during the infection. Though not protective, treatment of YFV-infected, adult BALB/c mice with U0126 resulted in significant reduction of virus titers in brains. Collectively, our data suggest the potential targeting of the MEK1/2 kinase as a therapeutic tool against diseases caused by flaviviruses such as yellow fever, adverse events associated with yellow fever vaccination and dengue.

  18. Screening of Dengue virus antiviral activity of marine seaweeds by an in situ enzyme-linked immunosorbent assay.

    Directory of Open Access Journals (Sweden)

    Andrea Cristine Koishi

    Full Text Available Dengue is a significant public health problem worldwide. Despite the important social and clinical impact, there is no vaccine or specific antiviral therapy for prevention and treatment of dengue virus (DENV infection. Considering the above, drug discovery research for dengue is of utmost importance; in addition natural marine products provide diverse and novel chemical structures with potent biological activities that must be evaluated. In this study we propose a target-free approach for dengue drug discovery based on a novel, rapid, and economic in situ enzyme-linked immunosorbent assay and the screening of a panel of marine seaweed extracts. The in situ ELISA was standardized and validated for Huh7.5 cell line infected with all four serotypes of DENV, among them clinical isolates and a laboratory strain. Statistical analysis showed an average S/B of 7.2 and Z-factor of 0.62, demonstrating assay consistency and reliability. A panel of fifteen seaweed extracts was then screened at the maximum non-toxic dose previously determined by the MTT and Neutral Red cytotoxic assays. Eight seaweed extracts were able to reduce DENV infection of at least one serotype tested. Four extracts (Phaeophyta: Canistrocarpus cervicornis, Padina gymnospora; Rhodophyta: Palisada perforate; Chlorophyta: Caulerpa racemosa were chosen for further evaluation, and time of addition studies point that they might act at an early stage of the viral infection cycle, such as binding or internalization.

  19. Antiviral Activity of Gold/Copper Sulfide Core/Shell Nanoparticles against Human Norovirus Virus-Like Particles.

    Directory of Open Access Journals (Sweden)

    Jessica Jenkins Broglie

    Full Text Available Human norovirus is a leading cause of acute gastroenteritis worldwide in a plethora of residential and commercial settings, including restaurants, schools, and hospitals. Methods for easily detecting the virus and for treating and preventing infection are critical to stopping norovirus outbreaks, and inactivation via nanoparticles (NPs is a more universal and attractive alternative to other physical and chemical approaches. Using norovirus GI.1 (Norwalk virus-like particles (VLPs as a model viral system, this study characterized the antiviral activity of Au/CuS core/shell nanoparticles (NPs against GI.1 VLPs for the rapid inactivation of HuNoV. Inactivation of VLPs (GI.1 by Au/CuS NPs evaluated using an absorbance-based ELISA indicated that treatment with 0.083 μM NPs for 10 min inactivated ~50% VLPs in a 0.37 μg/ml VLP solution and 0.83 μM NPs for 10 min completely inactivated the VLPs. Increasing nanoparticle concentration and/or VLP-NP contact time significantly increased the virucidal efficacy of Au/CuS NPs. Changes to the VLP particle morphology, size, and capsid protein were characterized using dynamic light scattering, transmission electron microscopy, and Western blot analysis. The strategy reported here provides the first reported proof-of-concept Au/CuS NPs-based virucide for rapidly inactivating human norovirus.

  20. Antiviral Activity of Gold/Copper Sulfide Core/Shell Nanoparticles against Human Norovirus Virus-Like Particles.

    Science.gov (United States)

    Broglie, Jessica Jenkins; Alston, Brittny; Yang, Chang; Ma, Lun; Adcock, Audrey F; Chen, Wei; Yang, Liju

    2015-01-01

    Human norovirus is a leading cause of acute gastroenteritis worldwide in a plethora of residential and commercial settings, including restaurants, schools, and hospitals. Methods for easily detecting the virus and for treating and preventing infection are critical to stopping norovirus outbreaks, and inactivation via nanoparticles (NPs) is a more universal and attractive alternative to other physical and chemical approaches. Using norovirus GI.1 (Norwalk) virus-like particles (VLPs) as a model viral system, this study characterized the antiviral activity of Au/CuS core/shell nanoparticles (NPs) against GI.1 VLPs for the rapid inactivation of HuNoV. Inactivation of VLPs (GI.1) by Au/CuS NPs evaluated using an absorbance-based ELISA indicated that treatment with 0.083 μM NPs for 10 min inactivated ~50% VLPs in a 0.37 μg/ml VLP solution and 0.83 μM NPs for 10 min completely inactivated the VLPs. Increasing nanoparticle concentration and/or VLP-NP contact time significantly increased the virucidal efficacy of Au/CuS NPs. Changes to the VLP particle morphology, size, and capsid protein were characterized using dynamic light scattering, transmission electron microscopy, and Western blot analysis. The strategy reported here provides the first reported proof-of-concept Au/CuS NPs-based virucide for rapidly inactivating human norovirus.

  1. An efficient antiviral strategy for targeting hepatitis B virus genome using transcription activator-like effector nucleases.

    Science.gov (United States)

    Chen, Jieliang; Zhang, Wen; Lin, Junyu; Wang, Fan; Wu, Min; Chen, Cuncun; Zheng, Ye; Peng, Xiuhua; Li, Jianhua; Yuan, Zhenghong

    2014-02-01

    The hepatitis B virus (HBV) is a DNA virus that can cause chronic hepatitis B (CHB) in humans. Current therapies for CHB infection are limited in efficacy and do not target the pre-existing viral genomic DNA, which are present in the nucleus as a covalently closed circular DNA (cccDNA) form. The transcription activator-like (TAL) effector nucleases (TALENs) are newly developed enzymes that can cleave sequence-specific DNA targets. Here, TALENs targeting the conserved regions of the viral genomic DNA among different HBV genotypes were constructed. The expression of TALENs in Huh7 cells transfected with monomeric linear full-length HBV DNA significantly reduced the viral production of HBeAg, HBsAg, HBcAg, and pgRNA, resulted in a decreased cccDNA level and misrepaired cccDNAs without apparent cytotoxic effects. The anti-HBV effect of TALENs was further demonstrated in a hydrodynamic injection-based mouse model. In addition, an enhanced antiviral effect with combinations of TALENs and interferon-α (IFN-α) treatment was observed and expression of TALENs restored HBV suppressed IFN-stimulated response element-directed transcription. Taken together, these data indicate that TALENs can specifically target and successfully inactivate the HBV genome and are potently synergistic with IFN-α, thus providing a potential therapeutic strategy for treating CHB infection.

  2. Cycluridine: A novel antiviral effective against flaviviruses.

    Science.gov (United States)

    Galabov, Angel S; Mukova, Lucia; Abashev, Yuriy P; Wassilewa, Lilia; Tzvetkov, Petko; Minkov, Vassil; Barinskiy, Igor F; Rice, Charles M; Ouzounov, Sergey; Sidzhakova, Dorotea

    2017-08-01

    This review describes the contemporary state of research for antivirals effective against flaviviruses, especially focusing on inhibitors of the pestivirus causative agent of bovine viral diarrhoea virus. We highlight cycluridine, an originally synthesized Mannich's base [a tetrahydro-2(1H)-pyrimidinones derivative], as a highly effective antiviral possessing a strong inhibitory effect on bovine viral diarrhoea virus replication. Cycluridine was active against replication of a wide variety of bovine viral diarrhoea virus strains in cell cultures. The drug-sensitive period in the bovine viral diarrhoea virus replication cycle included the latent period and the exponential phase; a 90-min delay in the peak of viral RNA synthesis was observed. Cycluridine administered orally manifested a pronounced protective effect in calves with natural mucosal disease/viral diarrhoea and calves experimentally infected with bovine viral diarrhoea virus. Its magnitude of activity and selectivity places cycluridine in the lead among all known substances with anti- bovine viral diarrhoea virus activity. Additionally, cycluridine applied subcutaneously showed anti-tick-born encephalitis virus activity, manifesting a marked protective effect in mice infected with tick-born encephalitis virus. Cycluridine could be a prospective antiviral in veterinary and medical practice for the treatment of bovine viral diarrhoea virus and other flavivirus infections.

  3. Reduction of CCR5 with low-dose rapamycin enhances the antiviral activity of vicriviroc against both sensitive and drug-resistant HIV-1.

    Science.gov (United States)

    Heredia, Alonso; Latinovic, Olga; Gallo, Robert C; Melikyan, Gregory; Reitz, Marv; Le, Nhut; Redfield, Robert R

    2008-12-23

    Vicriviroc (VCV) is a chemokine (C-C motif) receptor 5 (CCR5) antagonist with potent anti-HIV activity that currently is being evaluated in phase III clinical trials. In the present study, donor CCR5 density (CCR5 receptors/CD4 lymphocytes) inversely correlated with VCV antiviral activity (Spearman's correlation test; r = 0.746, P = 0.0034). Low doses of the transplant drug rapamycin (RAPA) reduced CCR5 density and enhanced VCV antiviral activity. In drug interaction studies, the RAPA/VCV combination had considerable antiviral synergy (combination indexes of 0.1-0.04) in both multicycle and single-cycle infection of lymphocytes. The synergy between RAPA and VCV translated into dose reduction indexes of 8- to 41-fold reductions for RAPA and 19- to 658-fold reductions for VCV. RAPA enhanced VCV antiviral activity against both B and non-B clade isolates, potently suppressing clade G viruses with reported reduced sensitivities to VCV and to the licensed CCR5 antagonist maraviroc. Importantly, RAPA reduction of CCR5 density in lymphocytes sensitized VCV-resistant strains to VCV, inhibiting virus production by approximately 90%. We further demonstrated the role of CCR5 density on VCV activity against resistant virus in donor lymphocytes and in cell lines expressing varying CCR5 densities. Together, these results suggest that low doses of RAPA may increase the durability of VCV-containing regimens in patients by enhancing VCV viral suppression, by allowing the use of lower doses of VCV with reduced potential for toxicity, and by controlling emerging VCV-resistant variants.

  4. Mx1, Mx2 and Mx3 proteins from the gilthead seabream (Sparus aurata) show in vitro antiviral activity against RNA and DNA viruses.

    Science.gov (United States)

    Fernández-Trujillo, M A; García-Rosado, E; Alonso, M C; Castro, D; Álvarez, M C; Béjar, J

    2013-12-01

    Mx proteins are important components of the antiviral innate immune response mediated by type I interferon. Classically, these proteins have been considered to be triggered by viral RNA, thus showing activity against RNA viruses. Actually, three Mx proteins (SauMx1, SauMx2 and SauMx3) from gilthead seabream (Sparus aurata) have previously shown antiviral activity against a dsRNA virus: the infectious pancreatic necrosis virus (IPNV) in vitro. For further characterizing their antiviral spectrum, the activity of SauMx proteins were tested against three different viral pathogens of fish: the lymphocystis disease virus (LCDV, a dsDNA virus), a pathogen of gilthead seabream; the viral haemorrhagic septicaemia virus (VHSV, a ssRNA virus), to which gilthead seabream is considered a reservoir species; and the European sheatfish virus (ESV, a dsDNA virus), that has not been detected in gilthead seabream to date. Three clonal populations of CHSE-214 cells developed in a previous study, stably expressing SauMx1, SauMx2 and SauMx3, respectively, were challenged with the three viruses. Results combining cytopathic effects and virus yield reduction assays showed that SauMx1 protected the cells against VHSV and LCDV, SauMx2 protected against ESV and LCDV, and SauMx3 showed activity only against VHSV. This study, besides confirming the antiviral activity of the three gilthead seabream Mx proteins, is the first report of the protective effect of a fish Mx against DNA viruses. Additionally, it discloses a clear specificity between Mx proteins and virus targets, supporting the idea that the relationship between virus and Mx proteins is finely tuned.

  5. Do microRNAs induced by Viral Hemorrhagic Septicemia virus in rainbow trout (Oncorhynchus mykiss) possess anti-viral activity?

    DEFF Research Database (Denmark)

    Bela-Ong, Dennis; Schyth, Brian Dall; Lorenzen, Niels

    2013-01-01

    RNAs were also up regulated in the liver and muscle (vaccination site) of fish vaccinated with a DNA vaccine expressing the VHSV glycoprotein gene. Recent studies further indicate that the expression of these miRNAs is induced by interferons. In order to analyze if miRNA-462 and miRNA-731 have any anti...... processes. Some miRNAs have been shown to have direct anti-viral effects. We have previously observed and validated that the fish-specific miRNAs, miR-462 and miR-731, were among the most highly expressed miRNAs in rainbow trout liver following Viral hemorrhagic septicemia virus (VHSV) infection. These mi......-viral effects, we designed inhibitory synthetic oligonucleotides called antagomiRs or anti-miRNAs. These saline-formulated 2’-O-methylated Locked Nucleic Acid (LNA)-based antagomiRs were injected intraperitoneally into rainbow trout fingerlings followed by exposure of the fish to VHSV. Development of disease...

  6. Identification of antiviral mimetic peptides with interferon α-2b-like activity from a random peptide library using a novel functional biopanning method

    Institute of Scientific and Technical Information of China (English)

    Qi ZHANG; Gang BAI; Jia-qi CHEN; Wang TIAN; Yu CAO; Peng-wei PAN; Chao WANG

    2008-01-01

    Aim: To screen for interferon (IFN) α-2b mimetic peptides with antiviral activity. Methods: Selecting IFN receptor-binding peptides from a phage-display heptapeptide library using a novel functional biopanning method. This method was developed to identify peptides with activity against vesicular stomatitis virus (VSV) inducing cytopathic effects on WISH cells. Results: Sixteen positive clones were obtained after 3 rounds of functional selection. Ten clones were picked from these positive clones according to the results of phage ELISA and were sequenced. The amino acid sequences homologous to IFNα-2b were defined by residues AB loop 31-37, BC loop 68-74, C helix 93-99, CD loop 106-112, D helix 115-121, DE loop 132-138, and E helix 143-161. Two of the peptides, designated clones T3 and T9, aligned with the IFNAR2-binding domains (AB loop and E helix), were synthe-sized and designated as IR-7 and KP-7, respectively. Both KP-7 and IR-7 were found to compete with GFP/IFNtα-2b for receptor binding and mimicked the antivi-ral activity of IFNα-2b cooperatively. Conclusion: Two IFNα-2b mimetic peptides with antiviral activity were derived from a phage-display heptapeptide library using a novel functional selection method.

  7. Antimicrobial, Antiviral and Immunomodulatory Activity Studies of Pelargonium sidoides (EPs® 7630 in the Context of Health Promotion

    Directory of Open Access Journals (Sweden)

    Herbert Kolodziej

    2011-10-01

    Full Text Available Pelargonium species contribute significantly to the health care of a large population in the Southern African region, as part of a long-standing medical system intimately linked to traditional healing practices. Most notably, extracts of the roots of P. sidoides have commonly been applied for the treatment of dysentery and diarrhoea but only occasionally for respiratory complaints. Clinical trials have shown that a modern aqueous-ethanolic formulation of P. sidoides extracts (EPs® 7630 is an efficacious treatment for disorders of the respiratory tract, for example bronchitis and sinusitis. It should be noted that EPs® 7630 is the most widely investigated extract and therefore is the focus of this review. In order to provide a rationale for its therapeutic activity extracts have been evaluated for antibacterial activity and for their effects on non-specific immune functions. Only moderate direct antibacterial capabilities against a spectrum of bacteria, including Mycobacteria strains, have been noted. In contrast, a large body of in vitro studies has provided convincing evidence for an anti-infective principle associated with activation of the non-specific immune system. Interestingly, significant inhibition of interaction between bacteria and host cells, a key to the pathogenesis of respiratory tract infections, has emerged from recent studies. In addition, antiviral effects have been demonstrated, including inhibition of the replication of respiratory viruses and the enzymes haemagglutinin and neuraminidase. Besides, an increase of cilliary beat frequency of respiratory cells may contribute to the beneficial effects of P. sidoides extracts. This example provides a compelling argument for continuing the exploration of Nature and traditional medical systems as a source of therapeutically useful herbal medicines.

  8. CD40 activation rescues antiviral CD8⁺ T cells from PD-1-mediated exhaustion.

    Directory of Open Access Journals (Sweden)

    Masanori Isogawa

    Full Text Available The intrahepatic immune environment is normally biased towards tolerance. Nonetheless, effective antiviral immune responses can be induced against hepatotropic pathogens. To examine the immunological basis of this paradox we studied the ability of hepatocellularly expressed hepatitis B virus (HBV to activate immunologically naïve HBV-specific CD8⁺ T cell receptor (TCR transgenic T cells after adoptive transfer to HBV transgenic mice. Intrahepatic priming triggered vigorous in situ T cell proliferation but failed to induce interferon gamma production or cytolytic effector function. In contrast, the same T cells differentiated into cytolytic effector T cells in HBV transgenic mice if Programmed Death 1 (PD-1 expression was genetically ablated, suggesting that intrahepatic antigen presentation per se triggers negative regulatory signals that prevent the functional differentiation of naïve CD8⁺ T cells. Surprisingly, coadministration of an agonistic anti-CD40 antibody (αCD40 inhibited PD-1 induction and restored T cell effector function, thereby inhibiting viral gene expression and causing a necroinflammatory liver disease. Importantly, the depletion of myeloid dendritic cells (mDCs strongly diminished the αCD40 mediated functional differentiation of HBV-specific CD8⁺ T cells, suggesting that activation of mDCs was responsible for the functional differentiation of HBV-specific CD8⁺ T cells in αCD40 treated animals. These results demonstrate that antigen-specific, PD-1-mediated CD8⁺ T cell exhaustion can be rescued by CD40-mediated mDC-activation.

  9. C7L family of poxvirus host range genes inhibits antiviral activities induced by type I interferons and interferon regulatory factor 1.

    Science.gov (United States)

    Meng, Xiangzhi; Schoggins, John; Rose, Lloyd; Cao, Jingxin; Ploss, Alexander; Rice, Charles M; Xiang, Yan

    2012-04-01

    Vaccinia virus (VACV) K1L and C7L function equivalently in many mammalian cells to support VACV replication and antagonize antiviral activities induced by type I interferons (IFNs). While K1L is limited to orthopoxviruses, genes that are homologous to C7L are found in diverse mammalian poxviruses. In this study, we showed that the C7L homologues from sheeppox virus and swinepox virus could rescue the replication defect of a VACV mutant deleted of both K1L and C7L (vK1L(-)C7L(-)). Interestingly, the sheeppox virus C7L homologue could rescue the replication of vK1L(-)C7L(-) in human HeLa cells but not in murine 3T3 and LA-4 cells, in contrast to all other C7L homologues. Replacing amino acids 134 and 135 of the sheeppox virus C7L homologue, however, made it functional in the two murine cell lines, suggesting that these two residues are critical for antagonizing a putative host restriction factor which has some subtle sequence variation in human and murine cells. Furthermore, the C7L family of host range genes from diverse mammalian poxviruses were all capable of antagonizing type I IFN-induced antiviral activities against VACV. Screening of a library of more than 350 IFN-stimulated genes (ISGs) identified interferon-regulated factor 1 (IRF1) as an inhibitor of vK1L(-)C7L(-) but not wild-type VACV. Expression of either K1L or C7L, however, rendered vK1L(-)C7L(-) resistant to IRF1-induced antiviral activities. Altogether, our data show that K1L and C7L antagonize IRF1-induced antiviral activities and that the host modulation function of C7L is evolutionally conserved in all poxviruses that can readily replicate in tissue-cultured mammalian cells.

  10. Randomized phase I: safety, immunogenicity and mucosal antiviral activity in young healthy women vaccinated with HIV-1 Gp41 P1 peptide on virosomes

    OpenAIRE

    Geert Leroux-Roels; Cathy Maes; Frédéric Clement; Frank van Engelenburg; Marieke van den Dobbelsteen; Michael Adler; Mario Amacker; Lucia Lopalco; Morgane Bomsel; Anick Chalifour; Sylvain Fleury

    2013-01-01

    UNLABELLED: Mucosal antibodies harboring various antiviral activities may best protect mucosal surfaces against early HIV-1 entry at mucosal sites and they should be ideally induced by prophylactic HIV-1 vaccines for optimal prevention of sexually transmitted HIV-1. A phase I, double-blind, randomized, placebo-controlled trial was conducted in twenty-four healthy HIV-uninfected young women. The study objectives were to assess the safety, tolerability and immunogenicity of virosomes harboring ...

  11. Synthesis and Antiviral Activity of N-Phenylbenzamide Derivatives, a Novel Class of Enterovirus 71 Inhibitors

    Directory of Open Access Journals (Sweden)

    Zhuo-Rong Li

    2013-03-01

    Full Text Available A series of novel N-phenylbenzamide derivatives were synthesized and their anti-EV 71 activities were assayed in vitro. Among the compounds tested, 3-amino-N-(4-bromophenyl-4-methoxybenzamide (1e was active against the EV 71 strains tested at low micromolar concentrations, with IC50 values ranging from 5.7 ± 0.8–12 ± 1.2 μM, and its cytotoxicity to Vero cells (TC50 = 620 ± 0.0 μM was far lower than that of pirodavir (TC50 = 31 ± 2.2 μM. Based on these results, compound 1e is a promising lead compound for the development of anti-EV 71 drugs.

  12. Antiviral activity of tumor-suppressor pathways: clues from molecular piracy by KSHV.

    Science.gov (United States)

    Moore, P S; Chang, Y

    1998-04-01

    A common feature of many tumor viruses is that they possess genes that produce specific proteins to inhibit major cellular tumor-suppressor pathways. Despite intensive studies, the reasons why these diverse and unrelated viruses have independently evolved oncogenes remains obscure. Kaposi-sarcoma-associated herpesvirus (KSHV or HHV8) has pirated a number of recognizable cellular genes that are key to cell survival and proliferation. In this review, we provide an overview of the known activities of these viral genes and show that many of these pirated proteins affect the same cellular pathways targeted by other, unrelated tumor viruses. We speculate that tumor-suppressor pathways are used by the cell as a primary defense against persistent virus infection, in addition to their well-known activity in regulating cell proliferation.

  13. Synthesis of Nucleoside Analogues with Potential Antiviral Activity against Negative Strand RNA Virus Targets

    Science.gov (United States)

    1989-11-01

    75 out by the same enzyme responsible for the first phosphorylation. The primary target for their activity is the DNA polymerisation reaction against...was the 229 first nucleoside analogue to have clinical usage for the treatment of herpetic eye infections. It was closely followed by 5...sequence and also to see whether it was possible to make an acid chloride in the presence of hydroxyl groups or whether polymerisation or other side

  14. Discovery of BMS-955176, a Second Generation HIV-1 Maturation Inhibitor with Broad Spectrum Antiviral Activity.

    Science.gov (United States)

    Regueiro-Ren, Alicia; Liu, Zheng; Chen, Yan; Sin, Ny; Sit, Sing-Yuen; Swidorski, Jacob J; Chen, Jie; Venables, Brian L; Zhu, Juliang; Nowicka-Sans, Beata; Protack, Tricia; Lin, Zeyu; Terry, Brian; Samanta, Himadri; Zhang, Sharon; Li, Zhufang; Beno, Brett R; Huang, Xiaohua S; Rahematpura, Sandhya; Parker, Dawn D; Haskell, Roy; Jenkins, Susan; Santone, Kenneth S; Cockett, Mark I; Krystal, Mark; Meanwell, Nicholas A; Hanumegowda, Umesh; Dicker, Ira B

    2016-06-09

    HIV-1 maturation inhibition (MI) has been clinically validated as an approach to the control of HIV-1 infection. However, identifying an MI with both broad polymorphic spectrum coverage and good oral exposure has been challenging. Herein, we describe the design, synthesis, and preclinical characterization of a potent, orally active, second generation HIV-1 MI, BMS-955176 (2), which is currently in Phase IIb clinical trials as part of a combination antiretroviral regimen.

  15. Synthesis, pharmacological and antiviral activity of 1,3-thiazepine derivatives.

    Science.gov (United States)

    Struga, Marta; Kossakowski, Jerzy; Koziol, Anna E; Kedzierska, Ewa; Fidecka, Sylwia; La Colla, Paolo; Ibba, Cristina; Collu, Gabriella; Sanna, Giuseppina; Secci, Barbara; Loddo, Roberta

    2009-12-01

    The preparation of new fourteen thiourea and fourteen product of their condensation with 1,4-dibromobutane, viz. 1,3-thiazepine derivatives, of 10-isopropyl-8-methyl-4-aza-tricyclo[5.2.2.0(2,6)]undec-8-ene-3,5-dione and 1-isopropyl-7-methyl-4-aza-tricyclo[5.2.2.0(2,6)]undec-8-ene-3,5-dione is described. Elemental analysis, MS and (1)H NMR spectra confirmed the identity of the products. The molecular structure of linear disubstituted thiourea derivative and its cyclization product was determined by an X-ray crystal structure analysis. Two of new obtained compounds (6b' and 7a') were tested for their pharmacological activity on animal central nervous system (CNS) in behavioral animal tests. With relatively low acute toxicity (LD(50) lower than 2000 mg kg(-1) i.p.) they exhibited significant influence on spontaneous locomotor activity and body temperature. Additionally, compounds reduced number of the "head twitch" episodes after 5-hydroksytryptophan (5-HTP) administration. New compounds were evaluated in vitro against representatives of different virus classes, such as a HIV-1 (Retrovirus), a HBV (Hepadnavirus) and the single-stranded RNA(+) viruses Yellow fever virus (YFV) and Bovine viral diarrhea virus (BVDV), both belonging to Flaviridae. Three of new obtained compounds showed a modest activity against HIV-1 wt(IIIB), BVDV and YFV.

  16. Bioprospecting of Red Sea Sponges for Novel Antiviral Pharmacophores

    KAUST Repository

    O'Rourke, Aubrie

    2015-05-01

    Natural products offer many possibilities for the treatment of disease. More than 70% of the Earth’s surface is ocean, and recent exploration and access has allowed for new additions to this catalog of natural treasures. The Central Red Sea off the coast of Saudi Arabia serves as a newly accessible location, which provides the opportunity to bioprospect marine sponges with the purpose of identifying novel antiviral scaffolds. Antivirals are underrepresented in present day clinical trials, as well as in the academic screens of marine natural product libraries. Here a high-throughput pipeline was initiated by prefacing the antiviral screen with an Image-based High-Content Screening (HCS) technique in order to identify candidates with antiviral potential. Prospective candidates were tested in a biochemical or cell-based assay for the ability to inhibit the NS3 protease of the West Nile Virus (WNV NS protease) as well as replication and reverse transcription of the Human Immunodeficiency Virus 1 (HIV-1). The analytical chemistry techniques of High-Performance Liquid Chromatograpy (HPLC), Liquid Chromatography-Mass Spectrometry (LC-MS), and Nuclear Magnetic Resonance (NMR) where used in order to identify the compounds responsible for the characteristic antiviral activity of the selected sponge fractions. We have identified a 3-alkyl pyridinium from Amphimedon chloros as the causative agent of the observed WNV NS3 protease inhibition in vitro. Additionally, we identified debromohymenialdisine, hymenialdisine, and oroidin from Stylissa carteri as prospective scaffolds capable of HIV-1 inhibition.

  17. Antiviral activity of dolutegravir in subjects with failure on an integrase inhibitor-based regimen: week 24 phase 3 results from VIKING-3

    Directory of Open Access Journals (Sweden)

    Mills A

    2012-11-01

    Full Text Available Background VIKING-3 aimed to examine efficacy and safety of dolutegravir (DTG 50 mg twice daily in patients with resistance to multiple ARV classes, including integrase inhibitors (INI. Methods RAL and/or EVG-resistant (current or historical adult subjects with screening plasma HIV-1 RNA ≥500 c/mL and resistance to ≥2 other ART classes received open-label DTG 50 mg BID while continuing their failing regimen (without RAL/EVG. At Day 8 the background regimen was optimised and DTG continued. Activity of the optimized background regimen (OBR was determined by Monogram Net Assessment. Primary endpoints were antiviral efficacy at Day 8 and Week 24. Results 183 subjects enrolled, 124 with INI-resistance at screening and 59 with historical (but no screening resistance. Population was advanced: at BL, median CD4 140, prior ART 13 yrs, 56% CDC Class C; 79% had >2 NRTI, 75% >1 NNRTI, and 70% >2 PI resistance-associated mutations, and 61% had non-R5 HIV detected. Of the 114 subjects who had the opportunity to complete 24 weeks on study before data cutoff, 72 (63% had <50 c/mL RNA at Week 24 (SNAPSHOT algorithm. Mean HIV RNA declined by 1.4 log10 c/mL (95% CI: 1.3, 1.5; p < 0.001 at Day 8; response differed by genotype pathway (Table. In subjects with Q148 pathway mutations, virologic response decreased with increasing number of secondary mutations. Background overall susceptibility score (OSS was not associated with Wk 24 response: % <50 c/mL were 83%, 63%, 59% and 69% for OSS 0, 1, 2 and >2, respectively. Discontinuations due to adverse events were uncommon (6/183, 3%; the most common drug-related AEs were diarrhoea, nausea and headache, each reported in only 5% of subjects. Conclusion A majority of the highly treatment-experienced subjects in VIKING-3 achieved suppression with DTG-based therapy. Responses were associated with Baseline IN genotype but not OSS, highlighting the importance and independence of DTG antiviral activity. DTG had a low rate

  18. Activation and inactivation of antiviral CD8 T cell responses during murine pneumorvirus infection

    NARCIS (Netherlands)

    Claassen, E.A.W.; Kant, van der P.A.

    2005-01-01

    Pneumonia virus of mice (PVM) is a natural pathogen of mice and has been proposed as a tractable model for the replication of a pneumovirus in its natural host, which mimics human infection with human respiratory syncytial virus (RSV). PVM infection in mice is highly productive in terms of virus pro

  19. Balticolid: A New 12-Membered Macrolide with Antiviral Activity from an Ascomycetous Fungus of Marine Origin

    Directory of Open Access Journals (Sweden)

    Ulrike Lindequist

    2011-05-01

    Full Text Available A new 12-membered macrolide, balticolid (1 was isolated from the EtOAc extract of the culture broth of fungal strain 222 belonging to the Ascomycota, which was found on driftwood collected from the coast of the Greifswalder Bodden, Baltic Sea, Germany. The structure of balticolid was determined to be (3R,11R, (4E,8E-3-hydroxy-11-methyloxacyclododeca-4,8-diene-1,7-dione using extensive spectral data as well as the modified Mosher ester method. Balticolid (1 displayed anti-HSV-1 activity with an IC50 value of 0.45 µM.

  20. Virucidal activity presence in Trichilia glabra leaves Presencia de actividad antiviral en hojas de Trichilia glabra

    Directory of Open Access Journals (Sweden)

    M. Cella

    2004-09-01

    Full Text Available Different immunomodulatory activities present in Trichilia glabra (TG leaf extracts have already been described. Particularly, chloroform-methanol extracts were responsible for an in-vivo anti-inflammatory effect. The effect of such extracts on the infectivity of enveloped and naked viruses were investigated. Methanolic fraction extracts were active against herpes simplex virus type 1 (HSV-1 and vesicular stomatitis virus (VSV, while no activity against poliovirus type 3 was observed. VSV was slightly more affected than HSV-1: 2.8 log10 reduction in VSV titer against 2.4 log10reduction in HSV-1 titer when 0.25 mg/ml F2 fraction was tested and a reduction of 2.7 log10in VSV virus titer and of 1.5 log10in HSV-1 virus titer was observed when 0.25 mg/ml F3 fraction was tested. Results obtained in this work suggest a potential pharmaceutical use of TG extract components.Previamente se han descripto distintas actividades inmunomoduladoras, presentes en extractos de hojas de Trichilia glabra (TG. En particular, se ha demostrado una actividad antiinflamatoria presente en extractos metanólicos. En este trabajo se investigó la actividad virucida de dichos extractos sobre virus envueltos y desnudos. Distintos extractos metanólicos han inactivado en forma moderada los virus herpes simplex tipo 1 (HSV-1 y el virus de la estomatitis vesicular (VSV, mientras no evidenciaron actividad sobre poliovirus tipo 3. VSV resultó algo mas afectado que HSV-1: se observó una reducción en el título viral de 2,8 log10para VSV y de 2,4 log10para HSV-1 cuando se uso una concentración de 0,25 mg/ml de la fracción F2 y una reducción de 2,7 log10para VSV y de 1,5 log 10para HSV-1 cuando se usó una concentración de 0,25 mg/ml de la fracción F3. Los resultados obtenidos en este trabajo, sugieren un potencial uso farmacéutico de los componentes presentes en los extractos de TG.

  1. Studies of antiviral activity and cytotoxicity of Wrightia tinctoria and Morinda citrifolia

    Directory of Open Access Journals (Sweden)

    Selvam P

    2009-01-01

    Full Text Available Different extracts of leaf parts of Wrightia tinctoria and fruit powder of Morinda citrifolia have been studied against replication of HIV-1(IIIB in MT-4 cells and HCV in Huh 5.2 cells. Chloroform extract of Wrightia tinctoria exhibited a maximum protection of 48% against the cytopathic effect of HIV-1(IIIB in MT-4 cells. Fruit juice of Morinda citrifolia exhibited a displayed marked cytotoxic activity in lymphocyte (MT-4 cells (CC50: 0.19 mg/ml. The 50% effective concentration for inhibition of HCV subgenomic replicon replication in Huh 5-2 cells by Morinda citrifolia was 0.98 µg/ml and by chloroform extract of Wrightia tinctoria was 10 µg/ml. The concentration that reduced the growth of exponentially proliferating Huh 5-2 cells by 50% was greater than 50 µg/ml.

  2. The study of antiviral activity of the dietary supplement «Immuno-viral with vitamin C» against influenza A/Victoria virus strains

    Directory of Open Access Journals (Sweden)

    Ганна Сергіївна Шумова

    2016-01-01

    Full Text Available The implementation of combined remedies, having in their composition herbal material, that shows anti-inflammatory, antibacterial, antiviral, restorative, and immunotropic action, is one of promising directions in the search of effective agents for acute respiratory infections prevention and treatment.Aim. The purpose of our research was to determine antiviral activity of the dietary supplement «Immuno-viral with Vitamin C» in the form of hard capsules against influenza A/Victoria virus strains.Methods. Classic virological method of chick embryos contamination in the chorioallantoic membrane, immunofluorescence method for the obtained virus identification, and neutralization reaction in chick embryos has been used.Results. It has been determined that the dietary supplement components were non-toxic for chick embryos in dilution of 1:10 to 1:80; had antiviral activity against influenza A/Victoria prototype virus strain in dilution of 1:10 to 1:20; lethal toxic dose in dilution of 1:40. After administration of influenza A/Victoria prototype virus strain in chick embryos without incubation with the test remedy (passaging, the medicinal agent retained its initial properties, confirmed by infected embryo cells fluorescence and the further study of the subcultered strain in the inhibition hemagglutination test with chick erythrocytes.Conclusion. As a result of the carried out in experiment neutralization reaction in 9–11 days chick embryos by the method of contamination in the chorioallantoic membrane with further visualization and identification of material, containing the virus, by the immunofluorescence method of the infected cells specific fluorescence, antiviral properties of the dietary supplement «Immuno-viral with Vitamin C» components have been determined

  3. AVP-IC50 Pred: Multiple machine learning techniques-based prediction of peptide antiviral activity in terms of half maximal inhibitory concentration (IC50).

    Science.gov (United States)

    Qureshi, Abid; Tandon, Himani; Kumar, Manoj

    2015-11-01

    Peptide-based antiviral therapeutics has gradually paved their way into mainstream drug discovery research. Experimental determination of peptides' antiviral activity as expressed by their IC50 values involves a lot of effort. Therefore, we have developed "AVP-IC50 Pred," a regression-based algorithm to predict the antiviral activity in terms of IC50 values (μM). A total of 759 non-redundant peptides from AVPdb and HIPdb were divided into a training/test set having 683 peptides (T(683)) and a validation set with 76 independent peptides (V(76)) for evaluation. We utilized important peptide sequence features like amino-acid compositions, binary profile of N8-C8 residues, physicochemical properties and their hybrids. Four different machine learning techniques (MLTs) namely Support vector machine, Random Forest, Instance-based classifier, and K-Star were employed. During 10-fold cross validation, we achieved maximum Pearson correlation coefficients (PCCs) of 0.66, 0.64, 0.56, 0.55, respectively, for the above MLTs using the best combination of feature sets. All the predictive models also performed well on the independent validation dataset and achieved maximum PCCs of 0.74, 0.68, 0.59, 0.57, respectively, on the best combination of feature sets. The AVP-IC50 Pred web server is anticipated to assist the researchers working on antiviral therapeutics by enabling them to computationally screen many compounds and focus experimental validation on the most promising set of peptides, thus reducing cost and time efforts. The server is available at http://crdd.osdd.net/servers/ic50avp.

  4. Antiviral and Virucidal Activities of N-Cocoyl-L-Arginine Ethyl Ester

    Directory of Open Access Journals (Sweden)

    Hisashi Yamasaki

    2011-01-01

    Full Text Available Various amino acid-derived compounds, for example, Nα-Cocoyl-L-arginine ethyl ester (CAE, alkyloxyhydroxylpropylarginine, arginine cocoate, and cocoyl glycine potassium salt (Amilite, were examined for their virucidal activities against herpes simplex virus type 1 and 2 (HSV-1 and HSV-2, influenza A virus (IAV, and poliovirus type 1 (PV-1 in comparison to benzalkonium chloride (BKC and sodium dodecylsulfate (SDS as a cationic and anionic control detergent and also to other commercially available disinfectants. While these amino acid-derived compounds were all effective against HSV-1 and HSV-2, CAE and Amilite were the most effective. These two compounds were, however, not as effective against IAV, another enveloped virus, as against HSV. Cytotoxicity of CAE was weak; at 0.012%, only 5% of the cells were killed under the conditions, in which 100% cells were killed by either SDS or BKC. In addition to these direct virucidal effects, CAE inhibited the virus growth in the HSV-1- or PV-1-infected cells even at 0.01%. These results suggest a potential application of CAE as a therapeutic or preventive medicine against HSV superficial infection at body surface.

  5. Conformational adaptation of Asian macaque TRIMCyp directs lineage specific antiviral activity.

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    Laura M J Ylinen

    Full Text Available TRIMCyps are anti-retroviral proteins that have arisen independently in New World and Old World primates. All TRIMCyps comprise a CypA domain fused to the tripartite domains of TRIM5alpha but they have distinct lentiviral specificities, conferring HIV-1 restriction in New World owl monkeys and HIV-2 restriction in Old World rhesus macaques. Here we provide evidence that Asian macaque TRIMCyps have acquired changes that switch restriction specificity between different lentiviral lineages, resulting in species-specific alleles that target different viruses. Structural, thermodynamic and viral restriction analysis suggests that a single mutation in the Cyp domain, R69H, occurred early in macaque TRIMCyp evolution, expanding restriction specificity to the lentiviral lineages found in African green monkeys, sooty mangabeys and chimpanzees. Subsequent mutations have enhanced restriction to particular viruses but at the cost of broad specificity. We reveal how specificity is altered by a scaffold mutation, E143K, that modifies surface electrostatics and propagates conformational changes into the active site. Our results suggest that lentiviruses may have been important pathogens in Asian macaques despite the fact that there are no reported lentiviral infections in current macaque populations.

  6. Rapid Synthesis and Antiviral Activity of (Quinazolin-4-YlaminoMethyl-Phosphonates Through Microwave Irradiation

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    Baoan Song

    2012-06-01

    Full Text Available This study describes the simple synthesis of new (quinazolin-4-ylamino methylphosphonates via microwave irradiation. Substituted-2-aminobenzonitrile reacted with 1,1-dimethoxy-N,N-dimethylmethanamine at a reflux condition to obtain N'-(substituted-2-cyanophenyl-N,N-dimethylformamidine (1. The subsequent reaction of this intermediate product with α-aminophosphonate (2 in a solution containing glacial acetic acid in 2-propanol through microwave irradiation resulted in the formation of (quinazolin-4-ylaminomethyl-phosphonate derivatives 3a to 3x, which were unequivocally characterized by the spectral data and elemental analysis. The influence of the reaction conditions on the yield of 3a was investigated to optimize the synthetic conditions. The relative optimal conditions for the synthesis of 3a include a 1:1 molar ratio of N’-(2-cyanophenyl-N,N-dimethylformamidine to diethyl amino(phenylmethylphosphonate and a 4:1 volume ratio of isopropanol to HOAc in the solvent mixture, at a reaction temperature of 150 °C, with a microwave power of 100 W and a corresponding pressure of 150 psi for 20 min in the microwave synthesizer. The yield of 3a was approximately 79%, whereas those of 3b to 3x were approximately 77% to 86%. Some of the synthesized compounds displayed weak to good anti-Tobacco mosaic virus (TMV activity.

  7. A High Throughput In Vivo Model for Testing Delivery and Antiviral Effects of siRNAs in Vertebrates

    DEFF Research Database (Denmark)

    Schyth, Brian Dall; Lorenzen, Niels; Pedersen, Finn Skou

    2007-01-01

    Despite the promise of small interfering RNAs (siRNAs) in antiviral therapy, few in vivo studies of them as inhibitors of viral replication and disease have been published, a lack that is most probably due to problems with obtaining successful delivery. Here we introduce a novel in vivomodel comp...

  8. Functional Comparison of Mx1 from Two Different Mouse Species Reveals the Involvement of Loop L4 in the Antiviral Activity against Influenza A Viruses

    OpenAIRE

    2015-01-01

    The interferon-induced Mx1 gene is an important part of the mammalian defense against influenza viruses. Mus musculus Mx1 inhibits influenza A virus replication and transcription by suppressing the polymerase activity of viral ribonucleoproteins (vRNPs). Here, we compared the anti-influenza virus activity of Mx1 from Mus musculus A2G with that of its ortholog from Mus spretus. We found that the antiviral activity of M. spretus Mx1 was less potent than that of M. musculus Mx1. Comparison of th...

  9. Antiviral therapy against chronic hepatitis B in Brazil: high rates of lamivudine resistance mutations and correlation with HBV genotypes

    Directory of Open Access Journals (Sweden)

    Francisco Campello do Amaral Mello

    2012-05-01

    Full Text Available The effectiveness of antiviral treatments of chronic hepatitis B has been poorly studied in Brazil. Here, hepatitis B virus (HBV DNA positivity, drug resistance mutations and their association with HBV genotypes were evaluated in chronically HBV-infected patients under different drug regimens in Brazil. The study involved 129 patients under interferon or nucleos(tide analogue therapy for a median treatment time of 12 months. One hundred and five (81% of these patients were treated with lamivudine (LAM, either in monotherapy or in combination with newer drugs, such as entecavir (ETV or tenofovir (TDF. High (37.5-100% rates of HBV DNA positivity were observed with all but one drug regimen (LAM + ETV. However, patients that were treated with ETV alone, TDF alone or with LAM combination therapies had a mean viral load that was 3-4 log lower than patients treated with LAM monotherapy. Of the patients treated with LAM, 47% developed resistance mutations. HBV genotypes A (59.1%, D (30.3% and F (9.1% were found. There was no association between the presence of LAM resistance mutations and genotypes, HBeAg status or treatment duration. Nevertheless, the rtM204V mutation was observed more frequently (12/13, 92% in genotype A than in the others (p = 0.023. Six out of nine isolates that contained the rtM204I mutation belonged to genotype D and half of them displayed a single mutation. Genotype D isolates with the rtM204V variant preferentially displayed a triple mutation, while genotype A preferentially displayed a double mutation (p = 0.04.

  10. Self-assembled dopamine nanolayers wrapped carbon nanotubes as carbon-carbon bi-functional nanocatalyst for highly efficient oxygen reduction reaction and antiviral drug monitoring

    Science.gov (United States)

    Khalafallah, Diab; Akhtar, Naeem; Alothman, Othman Y.; Fouad, H.; Abdelrazek khalil, Khalil

    2017-09-01

    Oxygen reduction reaction (ORR) catalysts are the heart of eco-friendly energy resources particularly low temperature fuel cells. Although valuable efforts have been devoted to synthesize high performance catalysts for ORR, considerable challenges are extremely desirable in the development of energy technologies. Herein, we report a simple self-polymerization method to build a thin film of dopamine along the tubular nanostructures of multi-walled carbon nanotubes (CNT) in a weak alkaline solution. The dopamine@CNT hybrid (denoted as DA@CNT) reveals an enhanced electrocatalytic activity towards ORR with highly positive onset potential and cathodic current as a result of their outstanding features of longitudinal mesoporous structure, high surface area, and ornamentation of DA layers with nitrogen moieties, which enable fast electron transport and fully exposed electroactive sites. Impressively, the as-obtained hybrid afford remarkable electrochemical durability for prolonged test time of 60,000 s compared to benchmark Pt/C (20 wt%) catalyst. Furthermore, the developed DA@CNT electrode was successfully applied to access the quality of antiviral drug named Valacyclovir (VCR). The DA@CNT electrode shows enhanced sensing performance in terms of large linear range (3-75 nM), low limit of detection (2.55 nM) than CNT based electrode, indicating the effectiveness of the DA coating. Interestingly, the synergetic effect of nanostructured DA and CNT can significantly boost the electronic configuration and exposure level of active species for ORR and biomolecule recognition. Therefore, the existing carbon-based porous electrocatalyst may find numerous translational applications as attractive alternative to noble metals in polymer electrolyte membrane fuel cells and quality control assessment of pharmaceutical and therapeutic drugs.

  11. Efficient Suppression of Hepatitis C Virus Replication by Combination Treatment with miR-122 Antagonism and Direct-acting Antivirals in Cell Culture Systems

    OpenAIRE

    Fanwei Liu; Tetsuro Shimakami; Kazuhisa Murai; Takayoshi Shirasaki; Masaya Funaki; Masao Honda; Seishi Murakami; Minkyung Yi; Hong Tang; Shuichi Kaneko

    2016-01-01

    Direct-acting antivirals (DAAs) against Hepatitis C virus (HCV) show effective antiviral activity with few side effects. However, the selection of DAA-resistance mutants is a growing problem that needs to be resolved. In contrast, miR-122 antagonism shows extensive antiviral effects among all HCV genotypes and a high barrier to drug resistance. In the present study, we evaluated three DAAs (simeprevir, daclatasvir, and sofosbuvir) in combination with anti-miR-122 treatment against HCV genotyp...

  12. Antiviral activity of hemocyanins

    Directory of Open Access Journals (Sweden)

    P Dolashka,

    2013-11-01

    Full Text Available Hemocyanins are giant biological macromolecules acting as oxygen-transporting glycoproteins. Most of them are respiratory proteins of arthropods and mollusks, but besides they also exhibit protecting effects against bacterial, fungal and viral invasions. As discovered by 2-DGE proteomics analyses, several proteins including hemocyanins of hemocytes from virus-infected arthropods increased upon infection, confirming hemocyanin’s role as part of the organism’s defence system. Based on the structural analyses of molluscan Hcs it is suggested that the carbohydrate chains of the glycoproteins seem to interact with surface-exposed amino acid or carbohydrate residues of the viruses through van der Waals interactions.

  13. Interferon induced IFIT family genes in host antiviral defense

    Science.gov (United States)

    Secretion of interferons (IFNs) from virus-infected cells is a hallmark of host antiviral immunity and in fact, IFNs exert their antiviral activities through the induction of antiviral proteins. The IFN-induced protein with tetratricopeptide repeats (IFITs) family is among hundreds of IF stimulated ...

  14. Broad antiviral activity of carbohydrate-binding agents against the four serotypes of dengue virus in monocyte-derived dendritic cells.

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    Marijke M F Alen

    Full Text Available BACKGROUND: Dendritic cells (DC, present in the skin, are the first target cells of dengue virus (DENV. Dendritic cell-specific intercellular adhesion molecule 3-grabbing non-integrin (DC-SIGN is present on DC and recognizes N-glycosylation sites on the E-glycoprotein of DENV. Thus, the DC-SIGN/E-glycoprotein interaction can be considered as an important target for inhibitors of viral replication. We evaluated various carbohydrate-binding agents (CBAs against all four described serotypes of DENV replication in Raji/DC-SIGN(+ cells and in monocyte-derived DC (MDDC. METHODOLOGY/PRINCIPAL FINDINGS: A dose-dependent anti-DENV activity of the CBAs Hippeastrum hybrid (HHA, Galanthus nivalis (GNA and Urtica dioica (UDA, but not actinohivin (AH was observed against all four DENV serotypes as analyzed by flow cytometry making use of anti-DENV antibodies. Remarkably, the potency of the CBAs against DENV in MDDC cultures was significantly higher (up to 100-fold than in Raji/DC-SIGN(+ cells. Pradimicin-S (PRM-S, a small-size non-peptidic CBA, exerted antiviral activity in MDDC but not in Raji/DC-SIGN(+ cells. The CBAs act at an early step of DENV infection as they bind to the viral envelope of DENV and subsequently prevent virus attachment. Only weak antiviral activity of the CBAs was detected when administered after the virus attachment step. The CBAs were also able to completely prevent the cellular activation and differentiation process of MDDC induced upon DENV infection. CONCLUSIONS/SIGNIFICANCE: The CBAs exerted broad spectrum antiviral activity against the four DENV serotypes, laboratory-adapted viruses and low passage clinical isolates, evaluated in Raji/DC-SIGN(+ cells and in primary MDDC.

  15. CRM1 Inhibitors for Antiviral Therapy

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    Cynthia Mathew

    2017-06-01

    Full Text Available Infectious diseases are a major global concern and despite major advancements in medical research, still cause significant morbidity and mortality. Progress in antiviral therapy is particularly hindered by appearance of mutants capable of overcoming the effects of drugs targeting viral components. Alternatively, development of drugs targeting host proteins essential for completion of viral lifecycle holds potential as a viable strategy for antiviral therapy. Nucleocytoplasmic trafficking pathways in particular are involved in several pathological conditions including cancer and viral infections, where hijacking or alteration of function of key transporter proteins, such as Chromosome Region Maintenance1 (CRM1 is observed. Overexpression of CRM1-mediated nuclear export is evident in several solid and hematological malignancies. Interestingly, CRM1-mediated nuclear export of viral components is crucial in various stages of the viral lifecycle and assembly. This review summarizes the role of CRM1 in cancer and selected viruses. Leptomycin B (LMB is the prototypical inhibitor of CRM1 potent against various cancer cell lines overexpressing CRM1 and in limiting viral infections at nanomolar concentrations in vitro. However, the irreversible shutdown of nuclear export results in high cytotoxicity and limited efficacy in vivo. This has prompted search for synthetic and natural CRM1 inhibitors that can potentially be developed as broadly active antivirals, some of which are summarized in this review.

  16. Antiviral Lead Compounds from Marine Sponges

    Directory of Open Access Journals (Sweden)

    Kenneth P. Minneman

    2010-10-01

    Full Text Available Marine sponges are currently one of the richest sources of pharmacologically active compounds found in the marine environment. These bioactive molecules are often secondary metabolites, whose main function is to enable and/or modulate cellular communication and defense. They are usually produced by functional enzyme clusters in sponges and/or their associated symbiotic microorganisms. Natural product lead compounds from sponges have often been found to be promising pharmaceutical agents. Several of them have successfully been approved as antiviral agents for clinical use or have been advanced to the late stages of clinical trials. Most of these drugs are used for the treatment of human immunodeficiency virus (HIV and herpes simplex virus (HSV. The most important antiviral lead of marine origin reported thus far is nucleoside Ara-A (vidarabine isolated from sponge Tethya crypta. It inhibits viral DNA polymerase and DNA synthesis of herpes, vaccinica and varicella zoster viruses. However due to the discovery of new types of viruses and emergence of drug resistant strains, it is necessary to develop new antiviral lead compounds continuously. Several sponge derived antiviral lead compounds which are hopedto be developed as future drugs are discussed in this review. Supply problems are usually the major bottleneck to the development of these compounds as drugs during clinical trials. However advances in the field of metagenomics and high throughput microbial cultivation has raised the possibility that these techniques could lead to the cost-effective large scale production of such compounds. Perspectives on biotechnological methods with respect to marine drug development are also discussed.

  17. Antiviral lead compounds from marine sponges

    KAUST Repository

    Sagar, Sunil

    2010-10-11

    Marine sponges are currently one of the richest sources of pharmacologically active compounds found in the marine environment. These bioactive molecules are often secondary metabolites, whose main function is to enable and/or modulate cellular communication and defense. They are usually produced by functional enzyme clusters in sponges and/or their associated symbiotic microorganisms. Natural product lead compounds from sponges have often been found to be promising pharmaceutical agents. Several of them have successfully been approved as antiviral agents for clinical use or have been advanced to the late stages of clinical trials. Most of these drugs are used for the treatment of human immunodeficiency virus (HIV) and herpes simplex virus (HSV). The most important antiviral lead of marine origin reported thus far is nucleoside Ara-A (vidarabine) isolated from sponge Tethya crypta. It inhibits viral DNA polymerase and DNA synthesis of herpes, vaccinica and varicella zoster viruses. However due to the discovery of new types of viruses and emergence of drug resistant strains, it is necessary to develop new antiviral lead compounds continuously. Several sponge derived antiviral lead compounds which are hopedto be developed as future drugs are discussed in this review. Supply problems are usually the major bottleneck to the development of these compounds as drugs during clinical trials. However advances in the field of metagenomics and high throughput microbial cultivation has raised the possibility that these techniques could lead to the cost-effective large scale production of such compounds. Perspectives on biotechnological methods with respect to marine drug development are also discussed. 2010 by the authors; licensee MDPI.

  18. Rationally Designed Interfacial Peptides Are Efficient In Vitro Inhibitors of HIV-1 Capsid Assembly with Antiviral Activity

    OpenAIRE

    Rebeca Bocanegra; María Nevot; Rosa Doménech; Inmaculada López; Olga Abián; Alicia Rodríguez-Huete; Cavasotto, Claudio N.; Adrián Velázquez-Campoy; Javier Gómez; Miguel Ángel Martínez; José Luis Neira; Mateu, Mauricio G.

    2011-01-01

    Virus capsid assembly constitutes an attractive target for the development of antiviral therapies; a few experimental inhibitors of this process for HIV-1 and other viruses have been identified by screening compounds or by selection from chemical libraries. As a different, novel approach we have undertaken the rational design of peptides that could act as competitive assembly inhibitors by mimicking capsid structural elements involved in intersubunit interfaces. Several discrete interfaces in...

  19. [Antimycoplasmic Activity of Fermentation Broth of Trichoderma harzianum Rifai F-180, an Organism Producing L-Lysine-α-Oxidase, an Antitumor and Antiviral Enzyme].

    Science.gov (United States)

    Smirnova, I P; Rakovskaya, I V

    2014-01-01

    A concentrate of the fermentation broth of Trichoderma harzianum Rifai F-180, an organism producing L-lysine-α-oxidase, an antitumor and antiviral enzyme, with the activity in the fermentation broth of 0.54-0.56 U/mI was recovered. The effect of the concentrate on the mycoplasmas growth was investigated for the first time. Two representatives of Mycoplasmafaceae, i.e. Mycoplasma hominis and Mycoplasma fermentans and one representative of Aholeplasmataceae. i. e. Aholeplasma laidlawii were used. It was shown that the fermentation broth inhibited the growth of Mycoplasma hominis after the preliminary exposure. The inhibition rate depended on the mycoplasma inoculation dose and the fermentation broth concentration.

  20. Antiviral, immunomodulatory, and free radical scavenging activities of a protein-enriched fraction from the larvae of the housefly, Musca domestica.

    Science.gov (United States)

    Ai, Hui; Wang, Furong; Zhang, Na; Zhang, Lingyao; Lei, Chaoliang

    2013-01-01

    In our previous study, protein-enriched fraction (PEF) that was isolated from the larvae of the housefly, Musca domestica L. (Diptera: Muscidae), showed excellent hepatoprotective activity as well as the potential for clinical application in therapy for liver diseases. In this study, antiviral, immunomodulatory, and free radical scavenging activities of PEF were evaluated. The antiviral results demonstrated that PEF inhibited the infection of avian influenza virus H9N2 and had a virucidal effect against the multicapsid nucleopolyhedrovirus of the alfalfa looper, Autographa californica Speyer (Lepidoptera: Noctuidae) in vitro. The mortality of silkworm larve in a PEF treatment group decreased significantly compared with a negative control. PEF showed excellent scavenging activity for 1,1-diphenyl-2-picrylhydrazyl and superoxide anion radicals, which were similar to those of ascorbic acid. The imunomodulatory results suggested that PEF could effectively improve immune function in experimental mice. Our results indicated that PEF could possibly be used for the prophylaxis and treatment of diseases caused by avian influenza virus infection. In addition, PEF with virucidal activity against insect viruses might provide useful for the development of antimicrobial breeding technology for economically important insects. As a natural product from insects, PEF could be a potential source for the discovery of potent antioxidant and immunomodulatory agents.

  1. Randomized Phase I: Safety, Immunogenicity and Mucosal Antiviral Activity in Young Healthy Women Vaccinated with HIV-1 Gp41 P1 Peptide on Virosomes.

    Directory of Open Access Journals (Sweden)

    Geert Leroux-Roels

    Full Text Available UNLABELLED: Mucosal antibodies harboring various antiviral activities may best protect mucosal surfaces against early HIV-1 entry at mucosal sites and they should be ideally induced by prophylactic HIV-1 vaccines for optimal prevention of sexually transmitted HIV-1. A phase I, double-blind, randomized, placebo-controlled trial was conducted in twenty-four healthy HIV-uninfected young women. The study objectives were to assess the safety, tolerability and immunogenicity of virosomes harboring surface HIV-1 gp41-derived P1 lipidated peptides (MYM-V101. Participants received placebo or MYM-V101 vaccine at 10 μg/dose or 50 μg/dose intramuscularly at week 0 and 8, and intranasally at week 16 and 24. MYM-V101 was safe and well-tolerated at both doses administered by the intramuscular and intranasal routes, with the majority of subjects remaining free of local and general symptoms. P1-specific serum IgGs and IgAs were induced in all high dose recipients after the first injection. After the last vaccination, vaginal and rectal P1-specific IgGs could be detected in all high dose recipients. Approximately 63% and 43% of the low and high dose recipients were respectively tested positive for vaginal P1-IgAs, while 29% of the subjects from the high dose group tested positive for rectal IgAs. Serum samples had total specific IgG and IgA antibody concentrations ≥ 0.4 μg/mL, while mucosal samples were usually below 0.01 μg/mL. Vaginal secretions from MYM-V101 vaccinated subjects were inhibiting HIV-1 transcytosis but had no detectable neutralizing activity. P1-specific Th1 responses could not be detected on PBMC. This study demonstrates the excellent safety and tolerability of MYM-V101, eliciting systemic and mucosal antibodies in the majority of subjects. Vaccine-induced mucosal anti-gp41 antibodies toward conserved gp41 motifs were harboring HIV-1 transcytosis inhibition activity and may contribute to reduce sexually-transmitted HIV-1. TRIAL

  2. Anti-viral properties and mode of action of standardized Echinacea purpurea extract against highly pathogenic avian Influenza virus (H5N1, H7N7 and swine-origin H1N1 (S-OIV

    Directory of Open Access Journals (Sweden)

    Schoop Roland

    2009-11-01

    Full Text Available Abstract Background Influenza virus (IV infections are a major threat to human welfare and animal health worldwide. Anti-viral therapy includes vaccines and a few anti-viral drugs. However vaccines are not always available in time, as demonstrated by the emergence of the new 2009 H1N1-type pandemic strain of swine origin (S-OIV in April 2009, and the acquisition of resistance to neuraminidase inhibitors such as Tamiflu® (oseltamivir is a potential problem. Therefore the prospects for the control of IV by existing anti-viral drugs are limited. As an alternative approach to the common anti-virals we studied in more detail a commercial standardized extract of the widely used herb Echinacea purpurea (Echinaforce®, EF in order to elucidate the nature of its anti-IV activity. Results Human H1N1-type IV, highly pathogenic avian IV (HPAIV of the H5- and H7-types, as well as swine origin IV (S-OIV, H1N1, were all inactivated in cell culture assays by the EF preparation at concentrations ranging from the recommended dose for oral consumption to several orders of magnitude lower. Detailed studies with the H5N1 HPAIV strain indicated that direct contact between EF and virus was required, prior to infection, in order to obtain maximum inhibition in virus replication. Hemagglutination assays showed that the extract inhibited the receptor binding activity of the virus, suggesting that the extract interferes with the viral entry into cells. In sequential passage studies under treatment in cell culture with the H5N1 virus no EF-resistant variants emerged, in contrast to Tamiflu®, which produced resistant viruses upon passaging. Furthermore, the Tamiflu®-resistant virus was just as susceptible to EF as the wild type virus. Conclusion As a result of these investigations, we believe that this standard Echinacea preparation, used at the recommended dose for oral consumption, could be a useful, readily available and affordable addition to existing control options

  3. Anti-viral properties and mode of action of standardized Echinacea purpurea extract against highly pathogenic avian influenza virus (H5N1, H7N7) and swine-origin H1N1 (S-OIV).

    Science.gov (United States)

    Pleschka, Stephan; Stein, Michael; Schoop, Roland; Hudson, James B

    2009-11-13

    Influenza virus (IV) infections are a major threat to human welfare and animal health worldwide. Anti-viral therapy includes vaccines and a few anti-viral drugs. However vaccines are not always available in time, as demonstrated by the emergence of the new 2009 H1N1-type pandemic strain of swine origin (S-OIV) in April 2009, and the acquisition of resistance to neuraminidase inhibitors such as Tamiflu (oseltamivir) is a potential problem. Therefore the prospects for the control of IV by existing anti-viral drugs are limited. As an alternative approach to the common anti-virals we studied in more detail a commercial standardized extract of the widely used herb Echinacea purpurea (Echinaforce, EF) in order to elucidate the nature of its anti-IV activity. Human H1N1-type IV, highly pathogenic avian IV (HPAIV) of the H5- and H7-types, as well as swine origin IV (S-OIV, H1N1), were all inactivated in cell culture assays by the EF preparation at concentrations ranging from the recommended dose for oral consumption to several orders of magnitude lower. Detailed studies with the H5N1 HPAIV strain indicated that direct contact between EF and virus was required, prior to infection, in order to obtain maximum inhibition in virus replication. Hemagglutination assays showed that the extract inhibited the receptor binding activity of the virus, suggesting that the extract interferes with the viral entry into cells. In sequential passage studies under treatment in cell culture with the H5N1 virus no EF-resistant variants emerged, in contrast to Tamiflu, which produced resistant viruses upon passaging. Furthermore, the Tamiflu-resistant virus was just as susceptible to EF as the wild type virus. As a result of these investigations, we believe that this standard Echinacea preparation, used at the recommended dose for oral consumption, could be a useful, readily available and affordable addition to existing control options for IV replication and dissemination.

  4. Antiviral potential of lactic acid bacteria and their bacteriocins.

    Science.gov (United States)

    Al Kassaa, I; Hober, D; Hamze, M; Chihib, N E; Drider, D

    2014-12-01

    Emerging resistance to antiviral agents is a growing public health concern worldwide as it was reported for respiratory, sexually transmitted and enteric viruses. Therefore, there is a growing demand for new, unconventional antiviral agents which may serve as an alternative to the currently used drugs. Meanwhile, published literature continues shedding the light on the potency of lactic acid bacteria (LAB) and their bacteriocins as antiviral agents. Health-promoting LAB probiotics may exert their antiviral activity by (1) direct probiotic-virus interaction; (2) production of antiviral inhibitory metabolites; and/or (3) via stimulation of the immune system. The aim of this review was to highlight the antiviral activity of LAB and substances they produce with antiviral activity.

  5. Expression of porcine Mx1 with FMDV IRES enhances the antiviral activity against foot-and-mouth disease virus in PK-15 cells.

    Science.gov (United States)

    Yuan, Bing; Fang, Hui; Shen, Chao; Zheng, Congyi

    2015-08-01

    Foot-and-mouth disease virus (FMDV) is the most contagious pathogen in cloven-hoofed (two-toed) animals. Due to the rapid replication and spread of FMDV, novel therapeutic strategies are greatly needed to reduce or block FMDV shedding in cases of disease outbreak. Here, we generated an IRES-Mx1 construct in which the internal ribosome entry site (IRES) of FMDV was inserted between the promoter and open reading frame (ORF) of porcine myxovirus resistance protein 1 (poMx1). This construct provides more powerful protection against FMDV infection than the IRES-IFN construct that was previously generated by our group. The results indicate that this IRES-Mx1 construct was able to express poMx1 12 h after transfection and induce a robust immune response. In contrast to the control, the proliferation of virus in transfected cells was significantly inhibited, as evaluated by morphology monitoring, real-time RT-PCR, virus titration and Western blot. In addition, we also found that the antiviral activity in cells transfected with pc-IRES-Mx1 was abolished when the JAK/STAT pathway was repressed, which indicates that the antiviral mechanism of poMx1 is JAK/STAT pathway dependent. Taken together, our data suggest that the antiviral activity of poMx1 is possibly produced by affecting the host cells themselves, instead of interacting with the virus directly. The new construct reported here could be used as a novel effective therapy against FMDV infection.

  6. High serum leptin is an independent risk factor for non-response patients with low viremia to antiviral treatment in chronic hepatitis C

    Institute of Scientific and Technical Information of China (English)

    Yuichiro Eguchi; Toshihiko Mizuta; Tsutomu Yasutake; Akitaka Hisatomi; Ryuichi Iwakiri; Iwata Ozaki; Kazuma Fujimoto

    2006-01-01

    AIM: To determine whether body weight and/or serum leptin were independent predictors of response to antiviral treatment in patients with chronic hepatitis C.METHODS: A retrospective evaluation was performed in 139 patients with chronic hepatitis C treated with interferon (IFN) from 1996 to 2000. Sustained response was defined as negative by hepatitis C virus (HCV) RNA analysis using PCR and normal transaminase at 24 wk after cessation of IFN therapy. Patients who remained positive for HCV RNA at the end of IFN treatment were defined as resistant to IFN therapy. Sex, age, body mass index (BMI) (≥ 25 vs < 25), complication of diabetes mellitus, serum leptin level (≥8.0 μg/L vs <8.0 μg/L),and the stage of liver fibrosis by needle biopsy (FL/F2 vs F3/F4) were examined.RESULTS: Sustained response was achieved in 33 patients (23.7%), while others failed to show a response to IFN therapy. Overall, the factors associated with sustained antiviral effects were HCV-RNA load, HCV genotype, serum leptin level, and stage of liver fibrosis evaluated by univariate analysis. BMI was not associated with any therapeutic effect of IFN. Multivariate analysis indicated that HCV-RNA load was a significant risk factor,but among the patients with low viremia (HCV-RNA < 100 MU/L), leptin level was an independent risk factor for IFN resistance. Namely, a high level of serum leptin attenuated the effect of IFN on both male and female patients with low viremia.CONCLUSION: High serum leptin level is a negative predictor of response to antiviral treatment in chronic hepatitis C with low viremia.

  7. Gene analysis of an antiviral protein SP-2 from Chinese wild silkworm, Bombyx mandarina Moore and its bio-activity assay

    Institute of Scientific and Technical Information of China (English)

    YAO HuiPeng; HE FangQing; GUO AiQin; CAO CuiPing; LU XingMeng; WU XiaoFeng

    2008-01-01

    The cDNA encoding an antiviral protein SP-2 against BmNPV was cloned from the midgut of Chinese wild silkworm, Bombyx mandarina Moore (GenBank access AY945210) based on the available informa-tion of the domesticated silkworm. Its cDNA was 855 bp encoding 284 amino acids with predicted mo-lecular weight of 29.6 kDa. Its full length in genomics was 1376 bp, including 5 exons and 4 introns. The expression analysis indicated that it was only expressed in midgut, and its expression level was higher during feeding stage of larval instars while very lower during the moltism and mature stages. The de-duced amino acid sequence of this protein showed eight-amino-acid variation compared with the counterpart of domesticated silkworm. Its antiviral activity was assayed through in vitro test. The re-sults indicated that it showed strong bioactivity against BmNPV, and its activity was 1.6 fold higher that the counterpart of domesticated silkworm.

  8. A review on antiviral activity of the Himalayan medicinal plants traditionally used to treat bronchitis and related symptoms.

    Science.gov (United States)

    Amber, Rahila; Adnan, Muhammad; Tariq, Akash; Mussarat, Sakina

    2017-02-01

    Bronchitis is a common respiratory tract infection of humans mainly caused by influenza virus, rhinovirus, adenovirus, coronavirus and respiratory syncytial virus. The aim of this review was to gather fragmented literature on ethnomedicinal plants used against bronchitis in the Himalayan region and their in-vitro validation against bronchitis causing viral pathogens. Present review contains ethnomedicines of total 55 plants from different countries of the Himalayas. Most of the literature reported was from India followed by Pakistan, China and Nepal. Familiarly used plant families for bronchitis treatment in the Himalayan region were Leguminosae (six plants) and Lamiaceae (five plants). Leaves and roots were the most common parts used in ethnomedicines against bronchitis. Of these 55 plants, only six plants have been studied in vitro against viral pathogens causing bronchitis. Different compounds like monoterpenoids, flavonoids, triterpenoids, iridoid glycosides, sesquiterpenes, benzoic and phenolic compounds were reportedly isolated from these plant extracts having strong antiviral potential. The Himalayan regions possess variety of ethnomedicinal plants used against respiratory diseases, but still there are only few studies related with their in-vitro validation. We invite the attention of researchers for detailed ethnopharmacological and phytochemical studies on unexplored plants used to treat bronchitis for the development of novel antiviral drugs. © 2016 Royal Pharmaceutical Society.

  9. HCV RNA Activates APCs via TLR7/TLR8 While Virus Selectively Stimulates Macrophages Without Inducing Antiviral Responses

    Science.gov (United States)

    Zhang, Yuwei; El-Far, Mohamed; Dupuy, Franck P.; Abdel-Hakeem, Mohamed S.; He, Zhong; Procopio, Francesco Andrea; Shi, Yu; Haddad, Elias K.; Ancuta, Petronela; Sekaly, Rafick-Pierre; Said, Elias A.

    2016-01-01

    The innate and adaptive immune systems fail to control HCV infection in the majority of infected individuals. HCV is an ssRNA virus, which suggests a role for Toll-like receptors (TLRs) 7 and 8 in initiating the anti-viral response. Here we demonstrate that HCV genomic RNA harbours specific sequences that initiate an anti-HCV immune response through TLR7 and TLR8 in various antigen presenting cells. Conversely, HCV particles are detected by macrophages, but not by monocytes and DCs, through a TLR7/8 dependent mechanism; this leads to chloroquine sensitive production of pro-inflammatory cytokines including IL-1β, while the antiviral type I Interferon response is not triggered in these cells. Antibodies to DC-SIGN, a c-type lectin selectively expressed by macrophages but not pDCs or mDCs, block the production of cytokines. Novel anti-HCV vaccination strategies should target the induction of TLR7/8 stimulation in APCs in order to establish potent immune responses against HCV. PMID:27385120

  10. In vitro antiviral activity of circular triple helix forming oligonucleotide RNA towards Feline Infectious Peritonitis virus replication.

    Science.gov (United States)

    Choong, Oi Kuan; Mehrbod, Parvaneh; Tejo, Bimo Ario; Omar, Abdul Rahman

    2014-01-01

    Feline Infectious Peritonitis (FIP) is a severe fatal immune-augmented disease in cat population. It is caused by FIP virus (FIPV), a virulent mutant strain of Feline Enteric Coronavirus (FECV). Current treatments and prophylactics are not effective. The in vitro antiviral properties of five circular Triple-Helix Forming Oligonucleotide (TFO) RNAs (TFO1 to TFO5), which target the different regions of virulent feline coronavirus (FCoV) strain FIPV WSU 79-1146 genome, were tested in FIPV-infected Crandell-Rees Feline Kidney (CRFK) cells. RT-qPCR results showed that the circular TFO RNAs, except TFO2, inhibit FIPV replication, where the viral genome copy numbers decreased significantly by 5-fold log10 from 10(14) in the virus-inoculated cells to 10(9) in the circular TFO RNAs-transfected cells. Furthermore, the binding of the circular TFO RNA with the targeted viral genome segment was also confirmed using electrophoretic mobility shift assay. The strength of binding kinetics between the TFO RNAs and their target regions was demonstrated by NanoITC assay. In conclusion, the circular TFOs have the potential to be further developed as antiviral agents against FIPV infection.

  11. In Vitro Antiviral Activity of Circular Triple Helix Forming Oligonucleotide RNA towards Feline Infectious Peritonitis Virus Replication

    Directory of Open Access Journals (Sweden)

    Oi Kuan Choong

    2014-01-01

    Full Text Available Feline Infectious Peritonitis (FIP is a severe fatal immune-augmented disease in cat population. It is caused by FIP virus (FIPV, a virulent mutant strain of Feline Enteric Coronavirus (FECV. Current treatments and prophylactics are not effective. The in vitro antiviral properties of five circular Triple-Helix Forming Oligonucleotide (TFO RNAs (TFO1 to TFO5, which target the different regions of virulent feline coronavirus (FCoV strain FIPV WSU 79-1146 genome, were tested in FIPV-infected Crandell-Rees Feline Kidney (CRFK cells. RT-qPCR results showed that the circular TFO RNAs, except TFO2, inhibit FIPV replication, where the viral genome copy numbers decreased significantly by 5-fold log10 from 1014 in the virus-inoculated cells to 109 in the circular TFO RNAs-transfected cells. Furthermore, the binding of the circular TFO RNA with the targeted viral genome segment was also confirmed using electrophoretic mobility shift assay. The strength of binding kinetics between the TFO RNAs and their target regions was demonstrated by NanoITC assay. In conclusion, the circular TFOs have the potential to be further developed as antiviral agents against FIPV infection.

  12. Antiviral, antifungal, and antiparasitic activities of fluoroquinolones optimized for treatment of bacterial infections: a puzzling paradox or a logical consequence of their mode of action?

    Science.gov (United States)

    Dalhoff, A

    2015-04-01

    This review summarizes evidence that commercially available fluoroquinolones used for the treatment of bacterial infections are active against other non-bacterial infectious agents as well. Any of these fluoroquinolones exerts, in parallel to its antibacterial action, antiviral, antifungal, and antiparasitic actions at clinically achievable concentrations. This broad range of anti-infective activities is due to one common mode of action, i.e., the inhibition of type II topoisomerases or inhibition of viral helicases, thus maintaining the selective toxicity of fluoroquinolones inhibiting microbial topoisomerases at low concentrations but mammalian topoisomerases at much higher concentrations. Evidence suggests that standard doses of the fluoroquinolones studied are clinically effective against viral and parasitic infections, whereas higher doses administered topically were active against Candida spp. causing ophthalmological infections. Well-designed clinical studies should be performed to substantiate these findings.

  13. Differential antiviral activity of Mx1, Mx2 and Mx3 proteins from gilthead seabream (Sparus aurata) against Infectious Pancreatic Necrosis Virus (IPNV).

    Science.gov (United States)

    Fernández-Trujillo, M A; García-Rosado, E; Alonso, M C; Borrego, J J; Alvarez, M C; Béjar, J

    2011-10-01

    Mx proteins are crucial effectors of the innate antiviral response mediated by the interferon type I signalling pathway. Recently, three Mx proteins, named SauMx1, SauMx2 and SauMx3, corresponding to three different genes, have been identified in the cultured marine species gilthead seabream (Sparus aurata). In this study, the three SauMx cDNAs were cloned into expression vectors and used for transfection of CHSE-214 cells. Monoclonal cell populations stably expressing each recombinant protein have been obtained and characterized. The protection conferred by each recombinant SauMx against Infectious Pancreatic Necrosis Virus (IPNV) infection has been in vitro evaluated, having found clear differences among them. According to the cytopathic effects and the virus yield reduction assays, only cells expressing SauMx2 and SauMx3 showed significant resistance to IPNV infection. Otherwise, quantitative RT real-time PCR assays suggested that each SauMx protein has a different target during the viral inhibition process. The differences observed among the three SauMx proteins are discussed in terms of their differential mechanism of action and antiviral specificity, suggesting, as a whole, to play a synergistic activity in the protection of gilthead seabream against IPNV.

  14. Recent advances in antiviral therapy.

    OpenAIRE

    Kinchington, D

    1999-01-01

    In the early 1980s many institutions in Britain were seriously considering whether there was a need for specialist departments of virology. The arrival of HIV changed that perception and since then virology and antiviral chemotherapy have become two very active areas of bio-medical research. Cloning and sequencing have provided tools to identify viral enzymes and have brought the day of the "designer drug" nearer to reality. At the other end of the spectrum of drug discovery, huge numbers of ...

  15. Chebulagic Acid, a Hydrolyzable Tannin, Exhibited Antiviral Activity in Vitro and in Vivo against Human Enterovirus 71

    Directory of Open Access Journals (Sweden)

    Lianfeng Zhang

    2013-05-01

    Full Text Available Human enterovirus 71 is one of the major causative agents of hand, foot and mouth disease in children under six years of age. Presently, no vaccines or antiviral drugs have been clinically available to employ against EV71. In this study, we demonstrate that treatment with chebulagic acid reduced the viral cytopathic effect on rhabdomyosarcoma cells with an IC50 of 12.5 μg/mL. The utilization of the chebulagic acid treatment on mice challenged with a lethal dose of enterovirus 71 was able to efficiently reduce mortality and relieve clinical symptoms through the inhibition of viral replication. Chebulagic acid may represent a potential therapeutic agent to control infections to enterovirus 71.

  16. High Serum Lipopolysaccharide-Binding Protein Level in Chronic Hepatitis C Viral Infection Is Reduced by Anti-Viral Treatments

    Science.gov (United States)

    Nien, Hsiao-Ching; Hsu, Shih-Jer; Su, Tung-Hung; Yang, Po-Jen; Sheu, Jin-Chuan; Wang, Jin-Town; Chow, Lu-Ping; Chen, Chi-Ling

    2017-01-01

    Background Lipopolysaccharide-binding protein (LBP) has been reported to associate with metabolic diseases, such as obesity, diabetes, and non-alcoholic fatty liver disease. Since chronic hepatitis C virus (HCV) infection is associated with metabolic derangements, the relationship between LBP and HCV deserves additional studies. This study aimed to determine the serum LBP level in subjects with or without HCV infection and investigate the change of its level after anti-viral treatments with or without interferon. Methods and Findings We recruited 120 non-HCV subjects, 42 and 17 HCV-infected subjects respectively treated with peginterferon α-2a/ribavirin and direct-acting antiviral drugs. Basic information, clinical data, serum LBP level and abdominal ultrasonography were collected. All the subjects provided written informed consent before being enrolled approved by the Research Ethics Committee of the National Taiwan University Hospital. Serum LBP level was significantly higher in HCV-infected subjects than non-HCV subjects (31.0 ± 8.8 versus 20.0 ± 6.4 μg/mL; p-value < 0.001). After multivariate analyses, LBP at baseline was independently associated with body mass index, hemoglobin A1c, alanine aminotransferase (ALT) and HCV infection. Moreover, the baseline LBP was only significantly positively associated with ALT and inversely with fatty liver in HCV-infected subjects. The LBP level significantly decreased at sustained virologic response (27.4 ± 6.6 versus 34.6 ± 7.3 μg/mL, p-value < 0.001; 15.9 ± 4.4 versus 22.2 ± 5.7 μg/mL, p-value = 0.001), regardless of interferon-based or -free therapy. Conclusions LBP, an endotoxemia associated protein might be used as an inflammatory biomarker of both infectious and non-infectious origins in HCV-infected subjects. PMID:28107471

  17. Antiviral susceptibility of highly pathogenic avian influenza A(H5N1) viruses isolated from poultry, Vietnam, 2009-2011.

    Science.gov (United States)

    Nguyen, Ha T; Nguyen, Tung; Mishin, Vasiliy P; Sleeman, Katrina; Balish, Amanda; Jones, Joyce; Creanga, Adrian; Marjuki, Henju; Uyeki, Timothy M; Nguyen, Dang H; Nguyen, Diep T; Do, Hoa T; Klimov, Alexander I; Davis, Charles T; Gubareva, Larisa V

    2013-12-01

    We assessed drug susceptibilities of 125 avian influenza A(H5N1) viruses isolated from poultry in Vietnam during 2009-2011. Of 25 clade 1.1 viruses, all possessed a marker of resistance to M2 blockers amantadine and rimantadine; 24 were inhibited by neuraminidase inhibitors. One clade 1.1 virus contained the R430W neuraminidase gene and reduced inhibition by oseltamivir, zanamivir, and laninamivir 12-, 73-, and 29-fold, respectively. Three of 30 clade 2.3.4 viruses contained a I223T mutation and showed 7-fold reduced inhibition by oseltamivir. One of 70 clade 2.3.2.1 viruses had the H275Y marker of oseltamivir resistance and exhibited highly reduced inhibition by oseltamivir and peramivir; antiviral agents DAS181 and favipiravir inhibited H275Y mutant virus replication in MDCK-SIAT1 cells. Replicative fitness of the H275Y mutant virus was comparable to that of wildtype virus. These findings highlight the role of drug susceptibility monitoring of H5N1 subtype viruses circulating among birds to inform antiviral stockpiling decisions for pandemic preparedness.

  18. Antiviral Susceptibility of Highly Pathogenic Avian Influenza A(H5N1) Viruses Isolated from Poultry, Vietnam, 2009–2011

    Science.gov (United States)

    Nguyen, Ha T.; Nguyen, Tung; Mishin, Vasiliy P.; Sleeman, Katrina; Balish, Amanda; Jones, Joyce; Creanga, Adrian; Marjuki, Henju; Uyeki, Timothy M.; Nguyen, Dang H.; Nguyen, Diep T.; Do, Hoa T.; Klimov, Alexander I.; Davis, Charles T.

    2013-01-01

    We assessed drug susceptibilities of 125 avian influenza A(H5N1) viruses isolated from poultry in Vietnam during 2009–2011. Of 25 clade 1.1 viruses, all possessed a marker of resistance to M2 blockers amantadine and rimantadine; 24 were inhibited by neuraminidase inhibitors. One clade 1.1 virus contained the R430W neuraminidase gene and reduced inhibition by oseltamivir, zanamivir, and laninamivir 12-, 73-, and 29-fold, respectively. Three of 30 clade 2.3.4 viruses contained a I223T mutation and showed 7-fold reduced inhibition by oseltamivir. One of 70 clade 2.3.2.1 viruses had the H275Y marker of oseltamivir resistance and exhibited highly reduced inhibition by oseltamivir and peramivir; antiviral agents DAS181 and favipiravir inhibited H275Y mutant virus replication in MDCK-SIAT1 cells. Replicative fitness of the H275Y mutant virus was comparable to that of wildtype virus. These findings highlight the role of drug susceptibility monitoring of H5N1 subtype viruses circulating among birds to inform antiviral stockpiling decisions for pandemic preparedness. PMID:24274711

  19. Efficacious early antiviral activity of HIV Gag- and Pol-specific HLA-B 2705-restricted CD8+ T cells

    DEFF Research Database (Denmark)

    Payne, Rebecca P; Kløverpris, Henrik; Sacha, Jonah B;

    2010-01-01

    control of HIV, we first characterized the CD8(+) T-cell responses of nine highly active antiretroviral therapy (HAART)-naïve B 2705-positive subjects. Unexpectedly, we observed a strong response to an HLA-B 2705-restricted Pol epitope, KRKGGIGGY (KY9), in 8/9 subjects. The magnitude of the KY9 response...

  20. Eupafolin and Ethyl Acetate Fraction of Kalanchoe gracilis Stem Extract Show Potent Antiviral Activities against Enterovirus 71 and Coxsackievirus A16

    Directory of Open Access Journals (Sweden)

    Ching-Ying Wang

    2013-01-01

    Full Text Available Enterovirus 71 (EV71 and coxsackievirus A16 (CoxA16 are main pathogens of hand-foot-and-mouth disease, occasionally causing aseptic meningitis and encephalitis in tropical and subtropical regions. Kalanchoe gracilis, Da-Huan-Hun, is a Chinese folk medicine for treating pain and inflammation, exhibiting antioxidant and anti-inflammatory activities. Our prior report (2012 cited K. gracilis leaf extract as moderately active against EV71 and CoxA16. This study further rates antienteroviral potential of K. gracilis stem (KGS extract to identify potent antiviral fractions and components. The extract moderately inhibits viral cytopathicity and virus yield, as well as in vitro replication of EV71 (IC50 = 75.18 μg/mL and CoxA16 (IC50 = 81.41 μg/mL. Ethyl acetate (EA fraction of KGS extract showed greater antiviral activity than that of n-butanol or aqueous fraction: IC50 values of 4.21 μg/mL against EV71 and 9.08 μg/mL against CoxA16. HPLC analysis, UV-Vis absorption spectroscopy, and plaque reduction assay indicate that eupafolin is a vital component of EA fraction showing potent activity against EV71 (IC50 = 1.39 μM and CoxA16 (IC50 = 5.24 μM. Eupafolin specifically lessened virus-induced upregulation of IL-6 and RANTES by inhibiting virus-induced ERK1/2, AP-1, and STAT3 signals. Anti-enteroviral potency of KGS EA fraction and eupafolin shows the clinical potential against EV71 and CoxA16 infection.

  1. Matrine displayed antiviral activity in porcine alveolar macrophages co-infected by porcine reproductive and respiratory syndrome virus and porcine circovirus type 2.

    Science.gov (United States)

    Sun, Na; Sun, Panpan; Lv, Haipeng; Sun, Yaogui; Guo, Jianhua; Wang, Zhirui; Luo, Tiantian; Wang, Shaoyu; Li, Hongquan

    2016-04-15

    The co-infection of porcine reproductive respiratory syndrome virus (PRRSV) and porcine circovirus type 2 (PCV2) is quite common in clinical settings and no effective treatment to the co-infection is available. In this study, we established the porcine alveolar macrophages (PAM) cells model co-infected with PRRSV/PCV2 with modification in vitro, and investigated the antiviral activity of Matrine on this cell model and further evaluated the effect of Matrine on virus-induced TLR3,4/NF-κB/TNF-α pathway. The results demonstrated PAM cells inoculated with PRRSV followed by PCV2 2 h later enhanced PRRSV and PCV2 replications. Matrine treatment suppressed both PRRSV and PCV2 infection at 12 h post infection. Furthermore, PRRSV/PCV2 co- infection induced IκBα degradation and phosphorylation as well as the translocation of NF-κB from the cytoplasm to the nucleus indicating that PRRSV/PCV2 co-infection induced NF-κB activation. Matrine treatment significantly down-regulated the expression of TLR3, TLR4 and TNF-α although it, to some extent, suppressed p-IκBα expression, suggesting that TLR3,4/NF-κB/TNF-α pathway play an important role of Matrine in combating PRRSV/PCV2 co-infection. It is concluded that Matrine possesses activity against PRRSV/PCV2 co-infection in vitro and suppression of the TLR3,4/NF-κB/TNF-α pathway as an important underlying molecular mechanism. These findings warrant Matrine to be further explored for its antiviral activity in clinical settings.

  2. Small molecules with antiviral activity against the Ebola virus [v1; ref status: indexed, http://f1000r.es/523

    OpenAIRE

    Nadia Litterman; Christopher Lipinski; Sean Ekins

    2015-01-01

    The recent outbreak of the Ebola virus in West Africa has highlighted the clear shortage of broad-spectrum antiviral drugs for emerging viruses. There are numerous FDA approved drugs and other small molecules described in the literature that could be further evaluated for their potential as antiviral compounds. These molecules are in addition to the few new antivirals that have been tested in Ebola patients but were not originally developed against the Ebola virus, and may play an important r...

  3. Insects antiviral and anticancer peptides: new leads for the future?

    Science.gov (United States)

    Slocinska, Malgorzata; Marciniak, Pawel; Rosinski, Grzegorz

    2008-01-01

    Insect produce wide range of protein and peptides as a first fast defense line against pathogen infection. These agents act in different ways including insect immune system activation or by direct impact on the target tumor cells or viruses. It has been shown that some of the insect peptides suppress viral gene and protein expression, rybosilate DNA, whereas others cause membrane lysis, induce apoptosis or arrest cell cycle. Several of the purified and characterized peptides of insect origin are very promising in treating of serious human diseases like human immunodeficiency virus (HIV), herpex simplex virus (HSV) or leukaemia. However, some obstacles need to be overcome. Cytotoxic activity of peptides, susceptibility to proteases or high cost of production remain still unsolved problems. Reports on the peptides antiviral and antitumour mechanisms are scanty. Thus, in this review we present characteristic, mode of action and potential medical applications of insects origin peptides with the antiviral and antitumour activity.

  4. Inorganic base-catalyzed formation of antivirally active N-substituted benzamides from α-amido sulfones and N-nucleophile

    Directory of Open Access Journals (Sweden)

    Wang Zhenchao

    2011-05-01

    Full Text Available Abstract Background Heteronucleophiles as well as carbanionic reagents can be used to react with α-amido sulfones, thus giving the opportunity to prepare a large array of amino derivatives. Since, novel 1,3,4-oxadiazole-2-thiol derivatives can serve as potent nucleophiles, we employed 5-subsititued phenyl-1,3,4-oxadiazole-2-thiols as the nucleophilic source of nitrogen in the reaction with α-amido sulfones. Results A series of N-substituted benzamides bearing 1,3,4-oxadiazol unit were prepared for the first time by the reaction of in situ generated protected imine from α-amido sulfones with 5-subsititued phenyl-1,3,4-oxadiazole-2-thiols as the source of nitrogen nucleophile. Some of the synthesized products displayed favourable antiviral activity against cucumber mosaic virus (CMV in preliminary antiviral activity tests. The title compounds 5c, 5o and 5r revealed curative activity of 42.2%, 48.7% and 40.5%, respectively against CMV (inhibitory rate compared to the commercial standard Ningnanmycin (53.4% at 500 μg/mL. Conclusion A practical synthetic route to N-benzoyl-α-amido sulfones by the reaction of 5-subsititued phenyl-1,3,4-oxadiazole-2-thiols as the source of nitrogen nucleophiles with in situ generated protected imine from N-benzoyl-α-amido sulfones is presented. The reaction catalyzed by an inorganic base has considerable significance to exploit the potential of α-amido sulfones in organic synthesis.

  5. [Renal toxicity of antiviral drugs].

    Science.gov (United States)

    Frasca', Giovanni M; Balestra, Emilio; Tavio, Marcello; Morroni, Manrico; Manarini, Gloria; Brigante, Fabiana

    2012-01-01

    Highly effective and powerful antiviral drugs have been introduced into clinical practice in recent years which are associated with an increased incidence of nephrotoxicity. The need of combining several drugs, the fragility of the patients treated, and the high susceptibility of the kidney are all factors contributing to renal injury. Many pathogenetic mechanisms are involved in the nephrotoxicity of antiviral drugs, including drug interaction with transport proteins in the tubular cell; direct cytotoxicity due to a high intracellular drug concentration; mitochondrial injury; and intrarenal obstruction or stone formation due to the low solubility of drugs at a normal urinary pH. As a result, various clinical pictures may be observed in patients treated with antiviral drugs, ranging from tubular dysfunction (Fanconi syndrome, renal tubular acidosis, nephrogenic diabetes insipidus) to acute renal failure (induced by tubular necrosis or crystal nephropathy) and kidney stones. Careful attention should be paid to prevent renal toxicity by evaluating the glomerular filtration rate before therapy and adjusting the drug dosage accordingly, avoiding the combination with other nephrotoxic drugs, and monitoring renal parameters on a regular basis while treating patients.

  6. Antiviral effect of methylated flavonol isorhamnetin against influenza.

    Directory of Open Access Journals (Sweden)

    Ahmed Abdal Dayem

    Full Text Available Influenza is an infectious respiratory disease with frequent seasonal epidemics that causes a high rate of mortality and morbidity in humans, poultry, and animals. Influenza is a serious economic concern due to the costly countermeasures it necessitates. In this study, we compared the antiviral activities of several flavonols and other flavonoids with similar, but distinct, hydroxyl or methyl substitution patterns at the 3, 3', and 4' positions of the 15-carbon flavonoid skeleton, and found that the strongest antiviral effect was induced by isorhamnetin. Similar to quercetin and kaempferol, isorhamnetin possesses a hydroxyl group on the C ring, but it has a 3'-methyl group on the B ring that is absent in quercetin and kaempferol. Co-treatment and pre-treatment with isorhamnetin produced a strong antiviral effect against the influenza virus A/PR/08/34(H1N1. However, isorhamnetin showed the most potent antiviral potency when administered after viral exposure (post-treatment method in vitro. Isorhamnetin treatment reduced virus-induced ROS generation and blocked cytoplasmic lysosome acidification and the lipidation of microtubule associated protein1 light chain 3-B (LC3B. Oral administration of isorhamnetin in mice infected with the influenza A virus significantly decreased lung virus titer by 2 folds, increased the survival rate which ranged from 70-80%, and decreased body weight loss by 25%. In addition, isorhamnetin decreased the virus titer in ovo using embryonated chicken eggs. The structure-activity relationship (SAR of isorhamnetin could explain its strong anti-influenza virus potency; the methyl group located on the B ring of isorhamnetin may contribute to its strong antiviral potency against influenza virus in comparison with other flavonoids.

  7. Antiviral effect of methylated flavonol isorhamnetin against influenza.

    Science.gov (United States)

    Abdal Dayem, Ahmed; Choi, Hye Yeon; Kim, Young Bong; Cho, Ssang-Goo

    2015-01-01

    Influenza is an infectious respiratory disease with frequent seasonal epidemics that causes a high rate of mortality and morbidity in humans, poultry, and animals. Influenza is a serious economic concern due to the costly countermeasures it necessitates. In this study, we compared the antiviral activities of several flavonols and other flavonoids with similar, but distinct, hydroxyl or methyl substitution patterns at the 3, 3', and 4' positions of the 15-carbon flavonoid skeleton, and found that the strongest antiviral effect was induced by isorhamnetin. Similar to quercetin and kaempferol, isorhamnetin possesses a hydroxyl group on the C ring, but it has a 3'-methyl group on the B ring that is absent in quercetin and kaempferol. Co-treatment and pre-treatment with isorhamnetin produced a strong antiviral effect against the influenza virus A/PR/08/34(H1N1). However, isorhamnetin showed the most potent antiviral potency when administered after viral exposure (post-treatment method) in vitro. Isorhamnetin treatment reduced virus-induced ROS generation and blocked cytoplasmic lysosome acidification and the lipidation of microtubule associated protein1 light chain 3-B (LC3B). Oral administration of isorhamnetin in mice infected with the influenza A virus significantly decreased lung virus titer by 2 folds, increased the survival rate which ranged from 70-80%, and decreased body weight loss by 25%. In addition, isorhamnetin decreased the virus titer in ovo using embryonated chicken eggs. The structure-activity relationship (SAR) of isorhamnetin could explain its strong anti-influenza virus potency; the methyl group located on the B ring of isorhamnetin may contribute to its strong antiviral potency against influenza virus in comparison with other flavonoids.

  8. STAT2/IRF9 directs a prolonged ISGF3-like transcriptional response and antiviral activity in the absence of STAT1

    Science.gov (United States)

    Blaszczyk, Katarzyna; Olejnik, Adam; Nowicka, Hanna; Ozgyin, Lilla; Chen, Yi-Ling; Chmielewski, Stefan; Kostyrko, Kaja; Wesoly, Joanna; Balint, Balint Laszlo; Lee, Chien-Kuo; Bluyssen, Hans A.R.

    2015-01-01

    Evidence is accumulating for the existence of a signal transducer and activator of transcription 2 (STAT2)/interferon regulatory factor 9 (IRF9)-dependent, STAT1-independent interferon alpha (IFNα) signalling pathway. However, no detailed insight exists into the genome-wide transcriptional regulation and the biological implications of STAT2/IRF9-dependent IFNα signalling as compared with interferon-stimulated gene factor 3 (ISGF3). In STAT1-defeicient U3C cells stably overexpressing human STAT2 (hST2-U3C) and STAT1-deficient murine embryonic fibroblast cells stably overexpressing mouse STAT2 (mST2-MS1KO) we observed that the IFNα-induced expression of 2′-5′-oligoadenylate synthase 2 (OAS2) and interferon-induced protein with tetratricopeptide repeats 1 (Ifit1) correlated with the kinetics of STAT2 phosphorylation, and the presence of a STAT2/IRF9 complex requiring STAT2 phosphorylation and the STAT2 transactivation domain. Subsequent microarray analysis of IFNα-treated wild-type (WT) and STAT1 KO cells overexpressing STAT2 extended our observations and identified ∼120 known antiviral ISRE-containing interferon-stimulated genes (ISGs) commonly up-regulated by STAT2/IRF9 and ISGF3. The STAT2/IRF9-directed expression profile of these IFN-stimulated genes (ISGs) was prolonged as compared with the early and transient response mediated by ISGF3. In addition, we identified a group of ‘STAT2/IRF9-specific’ ISGs, whose response to IFNα was ISGF3-independent. Finally, STAT2/IRF9 was able to trigger an antiviral response upon encephalomyocarditis virus (EMCV) and vesicular stomatitis Indiana virus (VSV). Our results further prove that IFNα-activated STAT2/IRF9 induces a prolonged ISGF3-like transcriptome and generates an antiviral response in the absence of STAT1. Moreover, the existence of ‘STAT2/IRF9-specific’ target genes predicts a novel role of STAT2 in IFNα signalling. PMID:25564224

  9. Antiviral Effect of Methylated Flavonol Isorhamnetin against Influenza

    OpenAIRE

    Ahmed Abdal Dayem; Hye Yeon Choi; Young Bong Kim; Ssang-Goo Cho

    2015-01-01

    Influenza is an infectious respiratory disease with frequent seasonal epidemics that causes a high rate of mortality and morbidity in humans, poultry, and animals. Influenza is a serious economic concern due to the costly countermeasures it necessitates. In this study, we compared the antiviral activities of several flavonols and other flavonoids with similar, but distinct, hydroxyl or methyl substitution patterns at the 3, 3', and 4' positions of the 15-carbon flavonoid skeleton, and found t...

  10. A STRATEGY FOR THE RAPID IDENTIFICATION OF FUNGAL METABOLITES AND THE DISCOVERY OF THE ANTIVIRAL ACTIVITY OF PYRENOCINE A AND HARZIANOPYRIDONE

    Directory of Open Access Journals (Sweden)

    Laura P. Ióca

    2016-07-01

    Full Text Available The isolation and identification of bioactive metabolites from complex extracts obtained from microbial growth media is a time consuming, costly, and labor-intensive task. A strategy to rapidly identify secondary metabolites isolated from extracts obtained from the culture media of marine-derived and endophytic fungal strains is described. Identification was achieved by HPLC-UV-MS and 1H NMR analyses in combination with data obtained from the Dictionary of Natural Products. Among the compounds identified, (--naphthoquinoneimine, citreorosein, emodin, pyrenocine A and harzianopyridone displayed moderate to potent antiviral activity. (--Naphthoquinoneimine was isolated as the enantiomer of its previously reported dextrorotatory congener, while 6,7-dihydroxy-2,2-dimethyl-4-chromanone is herein reported for the first time as a natural product.

  11. Virus and dsRNA-triggered transcriptional responses reveal key components of honey bee antiviral defense.

    Science.gov (United States)

    Brutscher, Laura M; Daughenbaugh, Katie F; Flenniken, Michelle L

    2017-07-25

    Recent high annual losses of honey bee colonies are associated with many factors, including RNA virus infections. Honey bee antiviral responses include RNA interference and immune pathway activation, but their relative roles in antiviral defense are not well understood. To better characterize the mechanism(s) of honey bee antiviral defense, bees were infected with a model virus in the presence or absence of dsRNA, a virus associated molecular pattern. Regardless of sequence specificity, dsRNA reduced virus abundance. We utilized next generation sequencing to examine transcriptional responses triggered by virus and dsRNA at three time-points post-infection. Hundreds of genes exhibited differential expression in response to co-treatment of dsRNA and virus. Virus-infected bees had greater expression of genes involved in RNAi, Toll, Imd, and JAK-STAT pathways, but the majority of differentially expressed genes are not well characterized. To confirm the virus limiting role of two genes, including the well-characterized gene, dicer, and a probable uncharacterized cyclin dependent kinase in honey bees, we utilized RNAi to reduce their expression in vivo and determined that virus abundance increased, supporting their involvement in antiviral defense. Together, these results further our understanding of honey bee antiviral defense, particularly the role of a non-sequence specific dsRNA-mediated antiviral pathway.

  12. Antiviral activity of chlorogenic acid against influenza A (H1N1/H3N2) virus and its inhibition of neuraminidase

    Science.gov (United States)

    Ding, Yue; Cao, Zeyu; Cao, Liang; Ding, Gang; Wang, Zhenzhong; Xiao, Wei

    2017-01-01

    Lonicera japonica Thunb, rich in chlorogenic acid (CHA), is used for viral upper respiratory tract infection treatment caused by influenza virus, parainfluenza virus, and respiratory syncytial virus, ect in China. It was reported that CHA reduced serum hepatitis B virus level and death rate of influenza virus-infected mice. However, the underlying mechanisms of CHA against the influenza A virus have not been fully elucidated. Here, the antiviral effects and potential mechanisms of CHA against influenza A virus were investigated. CHA revealed inhibitory against A/PuertoRico/8/1934(H1N1) (EC50 = 44.87 μM), A/Beijing/32/92(H3N2) (EC50 = 62.33 μM), and oseltamivir-resistant strains. Time-course analysis showed CHA inhibited influenza virus during the late stage of infectious cycle. Indirect immunofluorescence assay indicated CHA down-regulated the NP protein expression. The inhibition of neuraminidase activity confirmed CHA blocked release of newly formed virus particles from infected cells. Intravenous injection of 100 mg/kg/d CHA possessed effective antiviral activity in mice, conferring 60% and 50% protection from death against H1N1 and H3N2, reducing virus titres and alleviating inflammation in the lungs effectively. These results demonstrate that CHA acts as a neuraminidase blocker to inhibit influenza A virus both in cellular and animal models. Thus, CHA has potential utility in the treatment of the influenza virus infection. PMID:28393840

  13. Water extract of Pueraria lobata Ohwi has anti-viral activity against human respiratory syncytial virus in human respiratory tract cell lines

    Directory of Open Access Journals (Sweden)

    Tzeng-Jih Lin

    2013-12-01

    Full Text Available Human respiratory syncytial virus (HRSV infects all age groups and causes bronchiolitis, pneumonia, and acute respiratory distress syndrome with a significant mortality rate. To date, only ribavirin has been used to manage HRSV infection. However, ribavirin is expensive with an only modest effect. Furthermore, ribavirin has several side effects, which means it has limited clinical benefit. Pueraria lobata Ohwi (P. lobata is a common ingredient of Ge-Gen-Tang (Kakkon-to and Sheng-Ma-Ge-Gen-Tang (Shoma-kakkon-to, which are prescriptions of Chinese traditional medicine proven to have antiviral activity against HRSV. Therefore, it was hypothesized that P. lobata might be effective against HRSV. To find a cost-effective therapeutic modality, both human upper (HEp-2 and lower (A549 respiratory tract cell lines were used to test the hypothesis that P. lobata could inhibit HRSV-induced plaque formation. Results showed that the water extract of P. lobata was effective (p < 0.0001 against HRSV-induced plaque formation. P. lobata was more effective when given prior to viral inoculation (p < 0.0001 by inhibiting viral attachment (p < 0.0001 and penetration (p < 0.0001. However, supplementation with P. lobata could not stimulate interferon secretion after HRSV infection. In conclusion, P. lobata has antiviral activity against HRSV-induced plaque formation in airway mucosa mainly by inhibiting viral attachment and internalization. Further identification of effective constituents could contribute to the prevention of HRSV infection.

  14. 人防御素的抗病毒活性及机制%The Antiviral Activity and Mechanisms of Human Defensin

    Institute of Scientific and Technical Information of China (English)

    朱颜鑫(综述); 江滟(审校)

    2016-01-01

    防御素属于阳离子抗菌肽家族,具有广泛的抗微生物活性、细胞毒性和免疫趋化作用,在先天免疫系统中起着重要作用。近些年,随着防御素抗病毒的研究更加深入,越来越多的证据表明防御素不仅能直接灭活病毒和阻止病毒吸附、穿入及细胞内信号转导抑制病毒复制,还可以间接通过介导免疫反应发挥抗病毒作用。这种天然的抗菌肽具有抗包膜病毒和无包膜病毒的活性。%Defensins belong to the cationic antimicrobial peptide family and have extensive antimicrobial activity,cell toxicity and immune chemotaxis,playing an important role in the innate immune system.In recent years,with the deepening of the study on antiviral defense,more and more evidence showed that defensins not only can directly inactivate virus and prevent virus adsorption,penetration and intracellular sig-nal transduction and inhibit virus replication,they also play an indirect antiviral role by mediating immune response.The natural antibacterial peptides have the antibacterial activity against both enveloped and non-enveloped viruses.

  15. Semi-synthesis of oxygenated dolabellane diterpenes with highly in vitro anti-HIV-1 activity.

    Science.gov (United States)

    Pardo-Vargas, Alonso; Ramos, Freddy A; Cirne-Santos, Claudio Cesar; Stephens, Paulo Roberto; Paixão, Izabel Christina Palmer; Teixeira, Valeria Laneuville; Castellanos, Leonardo

    2014-09-15

    Research on dolabellane diterpenes of brown algae Dictyota spp. has shown that these diterpenoids have strong anti-HIV-1 activity, but there are not data about antiviral activity of dolabellane diterpenes isolated from octocorals, which are antipodes of those isolated from the brown algae. Dolabellanes 13-keto-1(R),11(S)-dolabella-3(E),7(E),12(18)-triene (1) and β-Araneosene (2) were isolated from the Caribbean octocoral Eunicea laciniata, and both showed low anti-HIV-1 activity and low toxicity. Since it was shown that oxygenated dolabellanes from algae have better anti-HIV-1 activity, in this work some derivatives of the main dolabellane of E. laciniata1 were obtained by epoxidation (3), epoxide opening (4), and allylic oxidation (5). The derivatives showed significant improvement in the anti-HIV-1potency (100-fold), being compounds 3 and 5 the most active ones. Their high antiviral activities, along with their low cytotoxicity, make them promissory antiviral compounds; and it is worth noting that the absolute configuration at the ring junction in the dolabellane skeleton does not seem to be determinant in the antiviral potency of these diterpeneoids.

  16. Silver Nanoparticles as Potential Antiviral Agents

    Directory of Open Access Journals (Sweden)

    Massimiliano Galdiero

    2011-10-01

    Full Text Available Virus infections pose significant global health challenges, especially in view of the fact that the emergence of resistant viral strains and the adverse side effects associated with prolonged use continue to slow down the application of effective antiviral therapies. This makes imperative the need for the development of safe and potent alternatives to conventional antiviral drugs. In the present scenario, nanoscale materials have emerged as novel antiviral agents for the possibilities offered by their unique chemical and physical properties. Silver nanoparticles have mainly been studied for their antimicrobial potential against bacteria, but have also proven to be active against several types of viruses including human imunodeficiency virus, hepatitis B virus, herpes simplex virus, respiratory syncytial virus, and monkey pox virus. The use of metal nanoparticles provides an interesting opportunity for novel antiviral therapies. Since metals may attack a broad range of targets in the virus there is a lower possibility to develop resistance as compared to conventional antivirals. The present review focuses on the development of methods for the production of silver nanoparticles and on their use as antiviral therapeutics against pathogenic viruses.

  17. PCBP2 enhances the antiviral activity of IFN-α against HCV by stabilizing the mRNA of STAT1 and STAT2.

    Directory of Open Access Journals (Sweden)

    Zhongshuai Xin

    Full Text Available Interferon-α (IFN-α is a natural choice for the treatment of hepatitis C, but half of the chronically infected individuals do not achieve sustained clearance of hepatitis C virus (HCV during treatment with IFN-α alone. The virus can impair IFN-α signaling and cellular factors that have an effect on the viral life cycles. We found that the protein PCBP2 is down-regulated in HCV-replicon containing cells (R1b. However, the effects and mechanisms of PCBP2 on HCV are unclear. To determine the effect of PCBP2 on HCV, overexpression and knockdown of PCBP2 were performed in R1b cells. Interestingly, we found that PCBP2 can facilitate the antiviral activity of IFN-α against HCV, although the RNA level of HCV was unaffected by either the overexpression or absence of PCBP2 in R1b cells. RIP-qRT-PCR and RNA half-life further revealed that PCBP2 stabilizes the mRNA of STAT1 and STAT2 through binding the 3'Untranslated Region (UTR of these two molecules, which are pivotal for the IFN-α anti-HCV effect. RNA pull-down assay confirmed that there were binding sites located in the C-rich tracts in the 3'UTR of their mRNAs. Stabilization of mRNA by PCBP2 leads to the increased protein expression of STAT1 and STAT2 and a consistent increase of phosphorylated STAT1 and STAT2. These effects, in turn, enhance the antiviral effect of IFN-α. These findings indicate that PCBP2 may play an important role in the IFN-α response against HCV and may benefit the HCV clinical therapy.

  18. Synthesis and antiviral and fungicidal activity evaluation of β-carboline, dihydro-β-carboline, tetrahydro-β-carboline alkaloids, and their derivatives.

    Science.gov (United States)

    Song, Hongjian; Liu, Yongxian; Liu, Yuxiu; Wang, Lizhong; Wang, Qingmin

    2014-02-05

    Six known β-carboline, dihydro-β-carboline, and tetrahydro-β-carboline alkaloids and a series of their derivatives were designed, synthesized, and evaluated for their anti-tobacco mosaic virus (TMV) and fungicidal activities for the first time. All of the alkaloids and some of their derivatives (compounds 3, 4, 14, and 19) exhibited higher anti-TMV activity than the commercial antiviral agent Ribavirin both in vitro and in vivo. Especially, the inactivation, curative, and protection activities of alkaloids Harmalan (62.3, 55.1, and 60.3% at 500 μg/mL) and tetrahydroharmane (64.2, 57.2, and 59.5% at 500 μg/mL) in vivo were much higher than those of Ribavirin (37.4, 36.2, and 38.5% at 500 μg/mL). A new derivative, 14, with optimized physicochemical properties, obviously exhibited higher activities in vivo (50.4, 43.9, and 47.9% at 500 μg/mL) than Ribavirin and other derivatives; therefore, 14 can be used as a new lead structure for the development of anti-TMV drugs. Moreover, most of these compounds exhibited good fungicidal activity against 14 kinds of fungi, especially compounds 4, 7, and 11.

  19. TRIM25 Enhances the Antiviral Action of Zinc-Finger Antiviral Protein (ZAP)

    Science.gov (United States)

    Lau, Zerlina; Cheung, Pamela; Schneider, William M.; Bozzacco, Leonia; Buehler, Eugen; Takaoka, Akinori; Rice, Charles M.; Felsenfeld, Dan P.; MacDonald, Margaret R.

    2017-01-01

    The host factor and interferon (IFN)-stimulated gene (ISG) product, zinc-finger antiviral protein (ZAP), inhibits a number of diverse viruses by usurping and intersecting with multiple cellular pathways. To elucidate its antiviral mechanism, we perform a loss-of-function genome-wide RNAi screen to identify cellular cofactors required for ZAP antiviral activity against the prototype alphavirus, Sindbis virus (SINV). In order to exclude off-target effects, we carry out stringent confirmatory assays to verify the top hits. Important ZAP-liaising partners identified include proteins involved in membrane ion permeability, type I IFN signaling, and post-translational protein modification. The factor contributing most to the antiviral function of ZAP is TRIM25, an E3 ubiquitin and ISG15 ligase. We demonstrate here that TRIM25 interacts with ZAP through the SPRY domain, and TRIM25 mutants lacking the RING or coiled coil domain fail to stimulate ZAP’s antiviral activity, suggesting that both TRIM25 ligase activity and its ability to form oligomers are critical for its cofactor function. TRIM25 increases the modification of both the short and long ZAP isoforms by K48- and K63-linked polyubiquitin, although ubiquitination of ZAP does not directly affect its antiviral activity. However, TRIM25 is critical for ZAP’s ability to inhibit translation of the incoming SINV genome. Taken together, these data uncover TRIM25 as a bona fide ZAP cofactor that leads to increased ZAP modification enhancing its translational inhibition activity. PMID:28060952

  20. Sulfated Alkyl Glucopyranans with Potent Antiviral Activity Synthesized by Ring-Opening Copolymerization of Anhydroglucose and Alkyl Anhydroglucose Monomers

    Directory of Open Access Journals (Sweden)

    Shiming Bai

    2015-01-01

    Full Text Available Sulfated glucopyranans having long alkyl groups were prepared by the ring-opening copolymerization of benzylated 1,6-anhydroglucopyranose with 3-O-octadecyl 1,6-anhydro-β-d-glucopyranose monomers, and subsequent deprotection and sulfation. Water-soluble sulfated glucopyranans with 2.8 and 4.7 mol% of 3-O-octadecyl group and lower molecular weights of M-n = 2.5 × 103–5.1 × 103 have potent anti-HIV activity at 0.05–1.25 μg/mL, even though sulfated polysaccharides with molecular weights below M-n = 6 × 103 had low anti-HIV activity. The interaction with poly-l-lysine as a model compound of proteins was analyzed by SPR, DSL, and zeta potential, indicating that the sulfated 3-O-octadecyl glucopyranans had high association and low dissociation rate constants, and the particle size increased after addition of poly-l-lysine. The anti-HIV activity was induced by electrostatic interaction between sulfate groups and amino groups of poly-l-lysine and by the synergistic effect of the hydrophobic long alkyl chain and hydrophilic sulfated group.

  1. Antiviral effect of lithium chloride on feline calicivirus in vitro.

    Science.gov (United States)

    Wu, Hongxia; Zhang, Xiaozhan; Liu, Chunguo; Liu, Dafei; Liu, Jiasen; Tian, Jin; Qu, Liandong

    2015-12-01

    Feline calicivirus (FCV) is a highly contagious pathogen that causes oral and upper respiratory tract disease in cats. Despite widespread vaccination, the prevalence of FCV remains high. Furthermore, a high gene mutation rate has led to the emergence of variants, and some infections are lethal. To date, there is no effective antiviral drug available for treating FCV infection. Here, we show that lithium chloride (LiCl) effectively suppresses the replication of FCV strain F9 in Crandell-Reese feline kidney (CRFK) cells. The antiviral activity of LiCl occurred primarily during the early stage of infection and in a dose-dependent manner. LiCl treatment also inhibited the cytopathic effect. LiCl treatment exhibited a strong inhibitory effect against a panel of other two reference strains and two recent FCV isolates from China. These results demonstrate that LiCl might be an effective anti-FCV drug for controlling FCV disease. Further studies are required to explore the antiviral activity of LiCl against FCV replication in vivo.

  2. Antiviral Innate Immune Activation in HIV-Infected Adults Negatively Affects H1/IC31-Induced Vaccine-Specific Memory CD4+ T Cells.

    Science.gov (United States)

    Lenz, Nicole; Schindler, Tobias; Kagina, Benjamin M; Zhang, Jitao David; Lukindo, Tedson; Mpina, Maxmillian; Bang, Peter; Kromann, Ingrid; Hoff, Søren T; Andersen, Peter; Reither, Klaus; Churchyard, Gavin J; Certa, Ulrich; Daubenberger, Claudia A

    2015-07-01

    Tuberculosis (TB) remains a global health problem, with vaccination being a necessary strategy for disease containment and elimination. A TB vaccine should be safe and immunogenic as well as efficacious in all affected populations, including HIV-infected individuals. We investigated the induction and maintenance of vaccine-induced memory CD4(+) T cells following vaccination with the subunit vaccine H1/IC31. H1/IC31 was inoculated twice on study days 0 and 56 among HIV-infected adults with CD4(+) lymphocyte counts of >350 cells/mm(3). Whole venous blood stimulation was conducted with the H1 protein, and memory CD4(+) T cells were analyzed using intracellular cytokine staining and polychromatic flow cytometry. We identified high responders, intermediate responders, and nonresponders based on detection of interleukin-2 (IL-2), tumor necrosis factor alpha (TNF-α), and gamma interferon (IFN-γ) expressing central (TCM) and effector memory CD4(+) T cells (TEM) 182 days after the first immunization. Amplicon-based transcript quantification using next-generation sequencing was performed to identify differentially expressed genes that correlated with vaccine-induced immune responses. Genes implicated in resolution of inflammation discriminated the responders from the nonresponders 3 days after the first inoculation. The volunteers with higher expression levels of genes involved in antiviral innate immunity at baseline showed impaired H1-specific TCM and TEM maintenance 6 months after vaccination. Our study showed that in HIV-infected volunteers, expression levels of genes involved in the antiviral innate immune response affected long-term maintenance of H1/IC31 vaccine-induced cellular immunity. (The clinical trial was registered in the Pan African Clinical Trials Registry [PACTR] with the identifier PACTR201105000289276.). Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  3. Atividade antiviral de extratos de plantas medicinais disponíveis comercialmente frente aos herpesvírus suíno e bovino Antiviral activity of commercially available medicinal plants on suid and bovine herpesviruses

    OpenAIRE

    V.M. Kaziyama; Fernandes,M.J.B.; I.C. Simoni

    2012-01-01

    O presente trabalho teve como objetivo pesquisar a atividade antiviral in vitro de plantas medicinais disponíveis comercialmente sobre herpesvírus suíno (SuHV-1) e bovino (BoHV-1). As espécies adquiridas foram Mikania glomerata, Cymbopogon citratus, Equisetum arvense, Peumus boldus, Solanum paniculatum, Malva sylvestris, Piper umbellatun e Solidago microglossa. A citotoxicidade dos extratos foi avaliada na linhagem celular MDBK pelas alterações morfológicas das células e obtenção da concentra...

  4. Differential contributions of plant Dicer-like proteins to antiviral defences against potato virus X in leaves and roots.

    Science.gov (United States)

    Andika, Ida Bagus; Maruyama, Kazuyuki; Sun, Liying; Kondo, Hideki; Tamada, Tetsuo; Suzuki, Nobuhiro

    2015-03-01

    Members of the plant Dicer-like (DCL) protein family are the critical components of the RNA-silencing pathway that mediates innate antiviral defence. The distinct antiviral role of each individual DCL protein has been established with mostly based on observations of aerial parts of plants. Thus, although the roots are closely associated with the life cycle of many plant viruses, little is known about the antiviral activities of DCL proteins in roots. We observed that antiviral silencing strongly inhibits potato virus X (PVX) replication in roots of some susceptible Solanaceae species. Silencing of the DCL4 homolog in Nicotiana benthamiana partially elevated PVX replication levels in roots. In Arabidopsis thaliana, which was originally considered a non-host plant of PVX, high levels of PVX accumulation in inoculated leaves were achieved by inactivation of DCL4, while in the upper leaves and roots, it required the additional inactivation of DCL2. In transgenic A. thaliana carrying the PVX amplicon with a green fluorescent protein (GFP) gene insertion in the chromosome (AMP243 line), absence of DCL4 enabled high levels of PVX-GFP accumulation in various aerial organs but not in the roots, suggesting that DCL4 is critical for intracellular antiviral silencing in shoots but not in roots, where it can be functionally compensated by other DCL proteins. Together, the high level of functional redundancies among DCL proteins may contribute to the potent antiviral activities against PVX replication in roots.

  5. Inhibition of enterovirus 71 (EV-71 infections by a novel antiviral peptide derived from EV-71 capsid protein VP1.

    Directory of Open Access Journals (Sweden)

    Chee Wah Tan

    Full Text Available Enterovirus 71 (EV-71 is the main causative agent of hand, foot and mouth disease (HFMD. In recent years, EV-71 infections were reported to cause high fatalities and severe neurological complications in Asia. Currently, no effective antiviral or vaccine is available to treat or prevent EV-71 infection. In this study, we have discovered a synthetic peptide which could be developed as a potential antiviral for inhibition of EV-71. Ninety five synthetic peptides (15-mers overlapping the entire EV-71 capsid protein, VP1, were chemically synthesized and tested for antiviral properties against EV-71 in human Rhabdomyosarcoma (RD cells. One peptide, SP40, was found to significantly reduce cytopathic effects of all representative EV-71 strains from genotypes A, B and C tested, with IC(50 values ranging from 6-9.3 µM in RD cells. The in vitro inhibitory effect of SP40 exhibited a dose dependent concentration corresponding to a decrease in infectious viral particles, total viral RNA and the levels of VP1 protein. The antiviral activity of SP40 peptide was not restricted to a specific cell line as inhibition of EV-71 was observed in RD, HeLa, HT-29 and Vero cells. Besides inhibition of EV-71, it also had antiviral activities against CV-A16 and poliovirus type 1 in cell culture. Mechanism of action studies suggested that the SP40 peptide was not virucidal but was able to block viral attachment to the RD cells. Substitutions of arginine and lysine residues with alanine in the SP40 peptide at positions R3A, R4A, K5A and R13A were found to significantly decrease antiviral activities, implying the importance of positively charged amino acids for the antiviral activities. The data demonstrated the potential and feasibility of SP40 as a broad spectrum antiviral agent against EV-71.

  6. Tannins from Hamamelis virginiana bark extract: characterization and improvement of the antiviral efficacy against influenza A virus and human papillomavirus.

    Directory of Open Access Journals (Sweden)

    Linda L Theisen

    Full Text Available Antiviral activity has been demonstrated for different tannin-rich plant extracts. Since tannins of different classes and molecular weights are often found together in plant extracts and may differ in their antiviral activity, we have compared the effect against influenza A virus (IAV of Hamamelis virginiana L. bark extract, fractions enriched in tannins of different molecular weights and individual tannins of defined structures, including pseudotannins. We demonstrate antiviral activity of the bark extract against different IAV strains, including the recently emerged H7N9, and show for the first time that a tannin-rich extract inhibits human papillomavirus (HPV type 16 infection. As the best performing antiviral candidate, we identified a highly potent fraction against both IAV and HPV, enriched in high molecular weight condensed tannins by ultrafiltration, a simple, reproducible and easily upscalable method. This ultrafiltration concentrate and the bark extract inhibited early and, to a minor extent, later steps in the IAV life cycle and tannin-dependently inhibited HPV attachment. We observed interesting mechanistic differences between tannin structures: High molecular weight tannin containing extracts and tannic acid (1702 g/mol inhibited both IAV receptor binding and neuraminidase activity. In contrast, low molecular weight compounds (<500 g/mol such as gallic acid, epigallocatechin gallate or hamamelitannin inhibited neuraminidase but not hemagglutination. Average molecular weight of the compounds seemed to positively correlate with receptor binding (but not neuraminidase inhibition. In general, neuraminidase inhibition seemed to contribute little to the antiviral activity. Importantly, antiviral use of the ultrafiltration fraction enriched in high molecular weight condensed tannins and, to a lesser extent, the unfractionated bark extract was preferable over individual isolated compounds. These results are of interest for developing and

  7. Antiviral Drugs: Seasonal Flu

    Centers for Disease Control (CDC) Podcasts

    2010-09-29

    In this podcast, Dr. Joe Bresee explains the nature of antiviral drugs and how they are used for seasonal flu.  Created: 9/29/2010 by National Center for Immunization and Respiratory Diseases (NCIRD).   Date Released: 9/29/2010.

  8. Spectroscopic, quantum chemical studies, Fukui functions, in vitro antiviral activity and molecular docking of 5-chloro-N-(3-nitrophenyl)pyrazine-2-carboxamide

    Science.gov (United States)

    Sebastian, S. H. Rosline; Al-Alshaikh, Monirah A.; El-Emam, Ali A.; Panicker, C. Yohannan; Zitko, Jan; Dolezal, Martin; VanAlsenoy, C.

    2016-09-01

    The molecular structural parameters and vibrational frequencies of 5-chloro-N-(3-nitrophenyl)pyrazine-2-carboxamide have been obtained using density functional theory technique in the B3LYP approximation and CC-pVDZ (5D, 7F) basis set. Detailed vibrational assignments of observed FT-IR and FT-Raman bands have been proposed on the basis of potential energy distribution and most of the modes have wavenumbers in the expected range. In the present case, the NH stretching mode is a doublet in the IR spectrum with a difference of 138 cm-1 and is red shifted by 76 cm-1 from the computed value, which indicates the weakening of NH bond resulting in proton transfer to the neighboring oxygen atom. The molecular electrostatic potential has been mapped for predicting sites and relative reactivities towards electrophilic and nucleophilic attack. The hyperpolarizability values are calculated in order to find its role in nonlinear optics. From the molecular docking study, amino acids Asn161, His162 forms H-bond with pyrazine ring and Trp184, Gln19 shows H-bond with Cdbnd O group and the docked ligand, title compound forms a stable complex with cathepsin K and the results suggest that the compound might exhibit inhibitory activity against cathepsin K. Moderate in vitro antiviral activity with EC50 at tens of μM was detected against feline herpes virus, coxsackie virus B4, and influenza A/H1N1 and A/H3N2.

  9. P1-Substituted Symmetry-Based Human Immunodeficiency Virus Protease Inhibitors with Potent Antiviral Activity against Drug-Resistant Viruses

    Energy Technology Data Exchange (ETDEWEB)

    DeGoey, David A.; Grampovnik, David J.; Chen, Hui-Ju; Flosi, William J.; Klein, Larry L.; Dekhtyar, Tatyana; Stoll, Vincent; Mamo, Mulugeta; Molla, Akhteruzzaman; Kempf, Dale J. (Abbott)

    2013-03-07

    Because there is currently no cure for HIV infection, patients must remain on long-term drug therapy, leading to concerns over potential drug side effects and the emergence of drug resistance. For this reason, new and safe antiretroviral agents with improved potency against drug-resistant strains of HIV are needed. A series of HIV protease inhibitors (PIs) with potent activity against both wild-type (WT) virus and drug-resistant strains of HIV was designed and synthesized. The incorporation of substituents with hydrogen bond donor and acceptor groups at the P1 position of our symmetry-based inhibitor series resulted in significant potency improvements against the resistant mutants. By this approach, several compounds, such as 13, 24, and 29, were identified that demonstrated similar or improved potencies compared to 1 against highly mutated strains of HIV derived from patients who previously failed HIV PI therapy. Overall, compound 13 demonstrated the best balance of potency against drug resistant strains of HIV and oral bioavailability in pharmacokinetic studies. X-ray analysis of an HIV PI with an improved resistance profile bound to WT HIV protease is also reported.

  10. Letermovir and inhibitors of the terminase complex: a promising new class of investigational antiviral drugs against human cytomegalovirus

    Directory of Open Access Journals (Sweden)

    Melendez DP

    2015-08-01

    Full Text Available Dante P Melendez,1,2 Raymund R Razonable1,2 1Division of Infectious Diseases, 2William J von Liebig Center for Transplantation and Clinical Regeneration, Mayo Clinic, Rochester, MN, USA Abstract: Infection with cytomegalovirus is prevalent in immunosuppressed patients. In solid organ transplant and hematopoietic stem cell transplant recipients, cytomegalovirus infection is associated with high morbidity and preventable mortality. Prevention and treatment of cytomegalovirus with currently approved antiviral drugs is often associated with side effects that sometimes preclude their use. Moreover, cytomegalovirus has developed mutations that confer resistance to standard antiviral drugs. During the last decade, there have been calls to develop novel antiviral drugs that could provide better options for prevention and treatment of cytomegalovirus. Letermovir (AIC246 is a highly specific antiviral drug that is currently undergoing clinical development for the management of cytomegalovirus infection. It acts by inhibiting the viral terminase complex. Letermovir is highly potent in vitro and in vivo against cytomegalovirus. Because of a distinct mechanism of action, it does not exhibit cross-resistance with other antiviral drugs. It is predicted to be active against strains that are resistant to ganciclovir, foscarnet, and cidofovir. To date, early-phase clinical trials suggest a very low incidence of adverse effects. Herein, we present a comprehensive review on letermovir, from its postulated novel mechanism of action to the results of most recent clinical studies. Keywords: cytomegalovirus, letermovir, AIC246, terminase, antivirals, transplantation 

  11. Development of Methods for Carrier-Mediated Targeted Delivery of Antiviral Compounds Using Monoclonal Antibodies

    Science.gov (United States)

    1987-04-01

    Conclusions Ribavirin and the S’-hemlsucclnate derivative of ribavirin were found to have highly significant in vitro antiviral activity against Punto Toro...for later characterization. Cooling equipment with programmable, controlled cooling rates, generally around l°C/minute, is ideal for freezing

  12. Induction and suppression of the innate antiviral responses by picornaviruses

    NARCIS (Netherlands)

    Feng, Q.

    2014-01-01

    On the front line of innate antiviral immune reactions is the type I interferon (IFN-α/β) system. IFN-α/β are small signaling molecules that can be produced by virtually all nucleated cells in our body upon virus infections, and induce a so-called “antiviral state” in neighboring cells by activating

  13. Development and Validation of a High Throughput Screen for Compounds with Antiviral Activity Against Encephalitic Alphaviruses

    Science.gov (United States)

    2010-09-15

    determined the compounds as cytotoxic if the viability is less than 85% in the screening. 1. Single dose study A. Small library screening We have...run on two independent days and the results are shown below (Table 8). The assay metrics meet the requirement for a successful HTS assay for a library ... screening . The assay performance was ascertained by testing plate-to-plate variation (data not shown). Table 8. Assay performance of the assay

  14. 水团花黄酮类成分及其体外抗病毒活性%Flavonoids from Adina pilulifera and Their in vitro Antiviral Activity

    Institute of Scientific and Technical Information of China (English)

    李药兰; 王辉; 范兆永; 苏妙贤; 薛珺一; 李婷; 岑颖洲

    2009-01-01

    Six flavonoids were isolated from the ethyl acetate fraction of the ethanol extract of Adina pilulifera. The chemical structures of these flavonoids were determined by spectroscopic analysis,and identified to be naringenin(l) .eriodic-tyol(2) ,quercetin(3) ,naringenin-7-0-β-O-glucopyranside(4) , eriodictyol-7-O-β-D-glucopyranside(5) ,and quercetin-3-O-β-D-glucopyranside(6). Among them,compounds 1,2,4 and 5 were isolated from A. Pilulifera for the first time. Antiviral tests using cytopathic effect(CPE) reduction assay and MTT method revealed that the flavonoid aglycones 1,2 and 3 possess in vitro antiviral activity against both respiratory syncytial virus (RSV) and coxsackie B3 virus ( CVB3) to different extents. In contrast,the flavonoid glucosides 4,5 and 6 did not show any anti-RSV and anti-CVB3 effects.%从水团花乙醇提物的乙酸乙酯部位分离到6个黄酮类化合物,根据光谱数据分别鉴定为柚皮素(1)、圣草酚(2)、槲皮素(3)、柚皮素7-O-β-D-葡萄糖苷(4)、圣草酚-7-O-β-D-葡萄糖苷(5)、槲皮素-3-O-β-D-葡萄糖苷(6),化合物1、2、4和5为首次从该植物中分离得到.采用细胞病变抑制法(CPE reduction assay)和MTT法测定化合物的体外抗病毒活性,结果显示,三个黄酮苷元1、2和3均具有不同程度的体外抑制呼吸道合胞病毒(RSV)和柯萨奇B3型病毒(CVB3)活性,反之,3个黄酮苷均不显示活性.

  15. N(4)-Acyl derivatives as lipophilic prodrugs of cidofovir and its 5-azacytosine analogue, (S)-HPMP-5-azaC: chemistry and antiviral activity.

    Science.gov (United States)

    Krečmerová, Marcela; Pohl, Radek; Masojídková, Milena; Balzarini, Jan; Snoeck, Robert; Andrei, Graciela

    2014-05-15

    Even number fatty acid residues-docosanoyl (behenoyl) and stearoyl were selected for introduction to the N(4)-position of (S)-1-[3-hydroxy-2-(phosphonomethoxy)propyl]cytosine) (HPMPC, cidofovir), and its 5-azacytosine counterpart, (S)-1-[3-hydroxy-2-(phosphonomethoxy)propyl]cytosine) (HPMP-5-azaC) with the aim to prepare a new type of lipophilic prodrugs. The study on the influence of these modifications to the stability and biological activity of both antivirals was performed. Different reactivity of both systems towards acylation reactions was also found: the 4-NH2 group of cidofovir was more reactive compared to that of HPMP-5-azaC. In 5-azacytosine derivatives, we found mostly a destabilizing effect of the N(4)-acylation but this could be compensated by a positive influence of the esterification of the phosphonate group. Chemical stability of the 5-azacytosine moiety in the HPMP series is increasing in the following order: HPMP-5-azaC

  16. Drosophila as a model for antiviral immunity

    Institute of Scientific and Technical Information of China (English)

    Susanna; Valanne; Mika; Rmet

    2010-01-01

    The fruit fly Drosophila melanogaster has been successfully used to study numerous biological processes including immune response.Flies are naturally infected with more than twenty RNA viruses making it a valid model organism to study host-pathogen interactions during viral infections.The Drosophila antiviral immunity includes RNA interference,activation of the JAK/STAT and other signaling cascades and other mechanisms such as autophagy and interactions with other microorganisms.Here we review Drosophila as an immunological research model as well as recent advances in the field ofDrosophila antiviral immunity.

  17. Tannins from Hamamelis virginiana bark extract: characterization and improvement of the antiviral efficacy against influenza A virus and human papillomavirus.

    Science.gov (United States)

    Theisen, Linda L; Erdelmeier, Clemens A J; Spoden, Gilles A; Boukhallouk, Fatima; Sausy, Aurélie; Florin, Luise; Muller, Claude P

    2014-01-01

    Antiviral activity has been demonstrated for different tannin-rich plant extracts. Since tannins of different classes and molecular weights are often found together in plant extracts and may differ in their antiviral activity, we have compared the effect against influenza A virus (IAV) of Hamamelis virginiana L. bark extract, fractions enriched in tannins of different molecular weights and individual tannins of defined structures, including pseudotannins. We demonstrate antiviral activity of the bark extract against different IAV strains, including the recently emerged H7N9, and show for the first time that a tannin-rich extract inhibits human papillomavirus (HPV) type 16 infection. As the best performing antiviral candidate, we identified a highly potent fraction against both IAV and HPV, enriched in high molecular weight condensed tannins by ultrafiltration, a simple, reproducible and easily upscalable method. This ultrafiltration concentrate and the bark extract inhibited early and, to a minor extent, later steps in the IAV life cycle and tannin-dependently inhibited HPV attachment. We observed interesting mechanistic differences between tannin structures: High molecular weight tannin containing extracts and tannic acid (1702 g/mol) inhibited both IAV receptor binding and neuraminidase activity. In contrast, low molecular weight compounds (tannins and, to a lesser extent, the unfractionated bark extract was preferable over individual isolated compounds. These results are of interest for developing and improving plant-based antivirals.

  18. Antiviral Polymer Therapeutics

    DEFF Research Database (Denmark)

    Smith, Anton Allen Abbotsford

    2014-01-01

    The field of drug delivery is in essence an exercise in engineered pharmacokinetics. Methods of doing so have been developed through the introduction of a vehicle carrying the drug, either by encapsulation or covalent attachment. The emergence of polymer therapeutics in anticancer therapy has...... the examples of polymer therapeutics being applied as an antiviral treatment are few and far in-between. This work aims to explore antiviral therapeutics, specifically in context of hepatitis virus C (HCV) and HIV. The current treatment of hepatitis C consists of a combination of drugs, of which ribavirin....... Curiously, the therapeutic window of ribavirin was vastly improved in several of these polymers suggesting altered pharmacodynamics. The applicability of liver-targeting sugar moieties is likewise tested in a similarly methodical approach. The same technique of synthesis was applied with zidovudine to make...

  19. IFN-gamma: Novel antiviral cytokines

    DEFF Research Database (Denmark)

    Ank, Nina; West, Hans; Paludan, Søren Riis

    2006-01-01

    and adaptive immune responses. Recently, a novel class of cytokines was discovered and named IFN-lambda (alternatively type III IFN or interleukin-28/29 [IL- 28/29]), based on IFN-like antiviral activity and induction of typical IFN-inducible genes. Here, we review the literature on IFN-lambda and discuss...

  20. Antiviral Defense Mechanisms in Honey Bees

    Science.gov (United States)

    Brutscher, Laura M.; Daughenbaugh, Katie F.; Flenniken, Michelle L.

    2015-01-01

    Honey bees are significant pollinators of agricultural crops and other important plant species. High annual losses of honey bee colonies in North America and in some parts of Europe have profound ecological and economic implications. Colony losses have been attributed to multiple factors including RNA viruses, thus understanding bee antiviral defense mechanisms may result in the development of strategies that mitigate colony losses. Honey bee antiviral defense mechanisms include RNA-interference, pathogen-associated molecular pattern (PAMP) triggered signal transduction cascades, and reactive oxygen species generation. However, the relative importance of these and other pathways is largely uncharacterized. Herein we review the current understanding of honey bee antiviral defense mechanisms and suggest important avenues for future investigation. PMID:26273564

  1. Antiviral activity and underlying molecular mechanisms of Matrine against porcine reproductive and respiratory syndrome virus in vitro.

    Science.gov (United States)

    Sun, Na; Wang, Zhi-Wei; Wu, Cai-Hong; Li, E; He, Jun-Ping; Wang, Shao-Yu; Hu, Yuan-Liang; Lei, Hai-Min; Li, Hong-Quan

    2014-04-01

    Porcine reproductive and respiratory syndrome (PRRS), caused by porcine reproductive and respiratory syndrome virus (PRRSV), is an acute infectious disease. The prevalence of PRRS has made swine industry suffered huge financial losses. Matrine, a natural compound, has been demonstrated to possess anti-PRRSV activity in Marc-145 cells. However, the underlying molecular mechanisms were still unknown. The main objective of our study was to discuss the effect of Matrine on PRRSV N protein expression and PRRSV induced apoptosis. Indirect immunofluorescence assay (IFA) and Western blot were used to assess the effect of Matrine on N protein expression. Apoptosis was analyzed by fluorescence staining. In addition, the effect of Matrine on caspase-3 activation was investigated by Western blot. Indirect immunofluorescence assay and Western blot analysis demonstrated that Matrine could inhibit N protein expression in Marc-145 cells. And Matrine was found to be able to impair PRRSV-induced apoptosis by inhibiting caspase-3 activation.

  2. In-vitro antiviral efficacy of ribavirin and interferon-alpha against canine distemper virus.

    Science.gov (United States)

    Carvalho, Otávio V; Saraiva, Giuliana L; Ferreira, Caroline G T; Felix, Daniele M; Fietto, Juliana L R; Bressan, Gustavo C; Almeida, Márcia R; Silva Júnior, Abelardo

    2014-10-01

    Canine distemper is a highly contagious disease with high incidence and lethality in the canine population. The objective of this study was to evaluate the efficacy of antiviral action with ribavirin (RBV), interferon-alpha (IFNα), and combinations of RBV and IFNα against canine distemper virus (CDV). Vero cells inoculated with CDV were treated with RBV, IFNα, and combinations of these drugs. The efficacy to inhibit viral replication was evaluated by adding the compounds at different times to determine which step of the viral replicative process was affected. Both drugs were effective against CDV in vitro. The IFNα was the most active compound, with an average IC50 (50% inhibitory concentration) value lower than the IC50 of the RBV. Ribavirin (RBV) was more selective than IFNα, however, and neither drug showed extracellular antiviral activity. The combination of RBV and IFNα exhibited antiviral activity for the intra- and extracellular stages of the replicative cycle of CDV, although the intracellular viral inhibition was higher. Both RBV and IFNα showed high antiviral efficacy against CDV, and furthermore, RBV + IFNα combinations have shown greater interference range in viral infectivity. These compounds could potentially be used to treat clinical disease associated with CDV infection.

  3. Functional Diversity of Anti-Lipopolysaccharide Factor Isoforms in Shrimp and Their Characters Related to Antiviral Activity

    OpenAIRE

    2015-01-01

    Anti-lipopolysaccharide factor (ALF) is a small protein with broad-spectrum antimicrobial activity, which has potential application in the disease control. Previously, we isolated seven ALF isoforms from the Chinese shrimp Fenneropenaeus chinensis. In the present study, their distributions in tissues of shrimp were analyzed and the data showed that different isoforms had different expression profiles, which suggested that they might have different functions. Then, the functions of different...

  4. Counteraction of tetherin antiviral activity by two closely related SIVs differing by the presence of a Vpu gene.

    Directory of Open Access Journals (Sweden)

    Kristina Nikovics

    Full Text Available In different primate lentiviruses, three proteins (Vpu, Env and Nef have been shown to have anti-tetherin activities. SIVden is a primate lentivirus harbored by a Cercopithecus denti (C. denti whose genome code for a Vpu gene. We have compared the activity of HIV-1 Vpu and of SIVden Vpu on tetherin proteins from humans, from C. denti and from Cercopithecus neglectus (C. neglectus, a monkey species that is naturally infected by SIVdeb, a virus closely related to SIVden but which does not encode a Vpu protein. Here, we demonstrate that SIVden Vpu, is active against C. denti tetherin, but not against human tetherin. Interestingly, C. neglectus tetherin was more sensitive to SIVden Vpu than to HIV-1 Vpu. We also identify residues in the tetherin transmembrane domains that are responsible for the species-specific Vpu effect. Simultaneous mutation (P40L and T45I of human tetherin conferred sensitivity to SIVden Vpu, while abolishing its sensitivity to HIV-1 Vpu. We next analyzed the anti-tetherin activity of the Nef proteins from HIV-1, SIVden and SIVdeb. All three Nef proteins were unable to rescue virus release in the presence of human or C. denti tetherin. Conversely, SIVdeb Nef enhanced virus release in the presence of C. neglectus tetherin, suggesting that SIVdeb relies on Nef in its natural host. Finally, while HIV-1 Vpu not only removed human tetherin from the cell surface but also directed it for degradation, SIVden Vpu only induced the redistribution of both C. denti and C. neglectus tetherins, resulting in a predominantly perinuclear localization.

  5. Role of cell-to-cell variability in activating a positive feedback antiviral response in human dendritic cells.

    Directory of Open Access Journals (Sweden)

    Jianzhong Hu

    Full Text Available In the first few hours following Newcastle disease viral infection of human monocyte-derived dendritic cells, the induction of IFNB1 is extremely low and the secreted type I interferon response is below the limits of ELISA assay. However, many interferon-induced genes are activated at this time, for example DDX58 (RIGI, which in response to viral RNA induces IFNB1. We investigated whether the early induction of IFNBI in only a small percentage of infected cells leads to low level IFN secretion that then induces IFN-responsive genes in all cells. We developed an agent-based mathematical model to explore the IFNBI and DDX58 temporal dynamics. Simulations showed that a small number of early responder cells provide a mechanism for efficient and controlled activation of the DDX58-IFNBI positive feedback loop. The model predicted distributions of single cell responses that were confirmed by single cell mRNA measurements. The results suggest that large cell-to-cell variation plays an important role in the early innate immune response, and that the variability is essential for the efficient activation of the IFNB1 based feedback loop.

  6. High antiviral effect of TiO2·PL–DNA nanocomposites targeted to conservative regions of (−RNA and (+RNA of influenza A virus in cell culture

    Directory of Open Access Journals (Sweden)

    Asya S. Levina

    2016-08-01

    Full Text Available Background: The development of new antiviral drugs based on nucleic acids is under scrutiny. An important problem in this aspect is to find the most vulnerable conservative regions in the viral genome as targets for the action of these agents. Another challenge is the development of an efficient system for their delivery into cells. To solve this problem, we proposed a TiO2·PL–DNA nanocomposite consisting of titanium dioxide nanoparticles and polylysine (PL-containing oligonucleotides.Results: The TiO2·PL–DNA nanocomposites bearing the DNA fragments targeted to different conservative regions of (−RNA and (+RNA of segment 5 of influenza A virus (IAV were studied for their antiviral activity in MDCK cells infected with the H1N1, H5N1, and H3N2 virus subtypes. Within the negative strand of each of the studied strains, the efficiency of DNA fragments increased in the direction of its 3’-end. Thus, the DNA fragment aimed at the 3’-noncoding region of (−RNA was the most efficient and inhibited the reproduction of different IAV subtypes by 3–4 orders of magnitude. Although to a lesser extent, the DNA fragments targeted at the AUG region of (+RNA and the corresponding region of (−RNA were also active. For all studied viral subtypes, the nanocomposites bearing the DNA fragments targeted to (−RNA appeared to be more efficient than those containing fragments aimed at the corresponding (+RNA regions.Conclusion: The proposed TiO2·PL–DNA nanocomposites can be successfully used for highly efficient and site-specific inhibition of influenza A virus of different subtypes. Some patterns of localization of the most vulnerable regions in IAV segment 5 for the action of DNA-based drugs were found. The (−RNA strand of IAV segment 5 appeared to be more sensitive as compared to (+RNA.

  7. Synthesis and Antiviral Activity of 5‑(4‑Chlorophenyl-1,3,4-Thiadiazole Sulfonamides

    Directory of Open Access Journals (Sweden)

    Yuping Zhang

    2010-12-01

    Full Text Available Starting from 4-chlorobenzoic acid, 10 new 5-(4-chlorophenyl-N-substituted-N-1,3,4-thiadiazole-2-sulfonamide derivatives were synthesized in six-steps. Esterification of 4-chlorobenzoic acid with methanol and subsequent hydrazination, salt formation and cyclization afforded 5-(4-chlorophen-yl-1,3,4-thiadiazole-2-thiol (5. Conversion of this intermediate into sulfonyl chloride 6, followed by nucleophilic attack of the amines gave the title sulfonamides 7a-7j whose structures were confirmed by NMR, IR and elemental analysis. The bioassay tests showed that compounds 7b and 7i possessed certain anti-tobacco mosaic virus activity.

  8. Streptovirudins, new antibiotics with antibacterial and antiviral activity. I. Culture taxonomy, fermentation and production of streptovirudin complex.

    Science.gov (United States)

    Thrum, H; Eckardt, K; Bradler, G; Fügner, R; Tonew, E; Tonew, M

    1975-07-01

    A new antibiotic complex has been isolated from cultures of Streptomyces strain No. JA 10124. On the basis of taxonomic studies, the producing microorganism is described as Streptomyces griseoflavus (Krainsky, 1914) Waksman et Henrici, 1948, subsp. thuringiensis subsp. nov., type strain JA 10124. The antibiotic complex, designated as streptovirudin, was isolated from extracts of both mycelium and culture filtrate. It is a white amorphous material which consists of ten closely related components including streptovirudins A, B, C, D and E. The streptovirudin complex exhibits antibiotic activity against Gram-positive bacteria, mycobacteria, and various DNA- and RNA-viruses.

  9. Anti-viral drug treatment along with immune activator IL-2: a control-based mathematical approach for HIV infection

    Science.gov (United States)

    Nath Chatterjee, Amar; Roy, Priti Kumar

    2012-02-01

    Recent development in antiretroviral treatment against HIV can help AIDS patients to fight against HIV. But the question that whether the disease is to be partially or totally eradicated from HIV infected individuals still remains unsolved. Usually, the most effective treatment for the disease is HAART which can only control the disease progression. But as the immune system becomes weak, the patients can not fight against other diseases. Immune cells are activated and proliferated by IL-2 after the identification of antigen. IL-2 production is impaired in HIV positive patients and intermitted administration of immune activator IL-2 together with HAART which is a more effective treatment to fight against the disease. Thus, its expediency is essential and is yet to be explored. In this article we anticipated a mathematical model of the effect of IL-2 together with RTIs therapy in HIV positive patients. Our analytical as well as numerical study shows that the optimal schedule of treatment for best result is to be obtained by systematic drug therapy. But at the last stage of treatment, the infection level raises again due to minimisation of drug dosage. Thus we study the perfect adherence of the drugs and found out if RTIs are taken with sufficient interval then for fixed interval of IL-2 therapy, certain amount of drug dosages may be able to sustain the immune system at pre-infection stage and the infected CD4+T cells are going towards extinction.

  10. Antiviral effect of cationic compounds on bacteriophages

    Directory of Open Access Journals (Sweden)

    Mai Huong eChatain-Ly

    2013-03-01

    Full Text Available The antiviral activity of several cationic compounds - cetytrimethylammonium (CTAB, chitosan, nisin and lysozyme - was investigated on the bacteriophage c2 (DNA head and non-contractile tail infecting Lactococcus strains and the bacteriophage MS2 (F-specific RNA infecting E.coli. Firstly, these activities were evaluated in a phosphate buffer pH 7- 10 mM. The CTAB had a virucidal effect on the Lactococcus bacteriophages, but not on the MS2. After 1 min of contact with 0.125 mM CTAB, the c2 population was reduced from 6 log(pfu/mL to 1,5 log(pfu/mL and completely deactivated at 1 mM. On the contrary, chitosan inhibited the MS2 more than it did the bacteriophages c2. No antiviral effect was observed for the nisin or the lysozyme on bacteriophages after 1 min of treatment. A 1 and 2.5 log reduction was respectively observed for nisin and lysozyme when the treatment time increased (5 or 10 min. These results showed that the antiviral effect depended both on the virus and structure of the antimicrobial compounds. The antiviral activity of these compounds was also evaluated in different physico-chemical conditions and in complex matrices. The antiviral activity of CTAB was impaired in acid pH and with an increase of the ionic strength. These results might be explained by the electrostatic interactions between cationic compounds and negatively charged particles such as bacteriophages or other compounds in a matrix. Milk proved to be protective suggesting the components of food could interfere with antimicrobial compounds.

  11. New ribosome-inactivating proteins with polynucleotide:adenosine glycosidase and antiviral activities from Basella rubra L. and bougainvillea spectabilis Willd.

    Science.gov (United States)

    Bolognesi, A; Polito, L; Olivieri, F; Valbonesi, P; Barbieri, L; Battelli, M G; Carusi, M V; Benvenuto, E; Del Vecchio Blanco, F; Di Maro, A; Parente, A; Di Loreto, M; Stirpe, F

    1997-12-01

    New single-chain (type 1) ribosome-inactivating proteins (RIPs) were isolated from the seeds of Basella rubra L. (two proteins) and from the leaves of Bougainvillea spectabilis Willd. (one protein). These RIPs inhibit protein synthesis both in a cell-free system, with an IC50 (concentration causing 50% inhibition) in the 10(-10) M range, and by various cell lines, with IC50S in the 10(-8)-10(-6) M range. All three RIPs released adenine not only from rat liver ribosomes but also from Escherichia coli rRNA, polyadenylic acid, herring sperm DNA, and artichoke mottled crinkle virus (AMCV) genomic RNA, thus being polynucleotide:adenosine glycosidases. The proteins from Basella rubra had toxicity to mice similar to that of most type 1 RIPs (Barbieri et al., 1993, Biochim Biophys Acta 1154: 237-282) with an LD50 (concentration that is 50% lethal) Bougainvillea spectabilis had an LD50 > 32 mg.kg-1. The N-terminal sequence of the two RIPs from Basella rubra had 80-93% identity, whereas it differed from the sequence of the RIP from Bougainvillea spectabilis. When tested with antibodies against various RIPs, the RIPs from Basella gave some cross-reactivity with sera against dianthin 32, and weak cross-reactivity with momordin I and momorcochin-S, whilst the RIP from Bougainvillea did not cross-react with any antiserum tested. An RIP from Basella rubra and one from Bougainvillea spectabilis were tested for antiviral activity, and both inhibited infection of Nicotiana benthamiana by AMCV.

  12. Potential antiviral lignans from the roots of Saururus chinensis with activity against Epstein-Barr virus lytic replication.

    Science.gov (United States)

    Cui, Hui; Xu, Bo; Wu, Taizong; Xu, Jun; Yuan, Yan; Gu, Qiong

    2014-01-24

    Epstein-Barr virus (EBV) is a member of the γ-herpes virus subfamily and has been implicated in the pathogenesis of several human malignancies. Bioassay-guided fractionation was conducted on an EtOAc-soluble extract of the roots of Saururus chinensis and monitored using an EBV lytic replication assay. This led to the isolation of 19 new (1-19) and nine known (20-28) lignans. The absolute configurations of the new lignans were established by Mosher's ester, ECD, and computational methods. Eight lignans, including three sesquineolignans (19, 23, and 24) and five dineolignans (3, 4, 26, 27, and 28), exhibited inhibitory effects toward EBV lytic replication with EC50 values from 1.09 to 7.55 μM and SI values from 3.3 to 116.4. In particular, manassantin B (27) exhibited the most promising inhibition, with an EC50 of 1.72 μM, low cytotoxicity, CC50 > 200 μM, and SI > 116.4. This is the first study demonstrating that lignans possess anti-EBV lytic replication activity.

  13. Small molecules with antiviral activity against the Ebola virus [v1; ref status: indexed, http://f1000r.es/523

    Directory of Open Access Journals (Sweden)

    Nadia Litterman

    2015-02-01

    Full Text Available The recent outbreak of the Ebola virus in West Africa has highlighted the clear shortage of broad-spectrum antiviral drugs for emerging viruses. There are numerous FDA approved drugs and other small molecules described in the literature that could be further evaluated for their potential as antiviral compounds. These molecules are in addition to the few new antivirals that have been tested in Ebola patients but were not originally developed against the Ebola virus, and may play an important role as we await an effective vaccine. The balance between using FDA approved drugs versus novel antivirals with minimal safety and no efficacy data in humans should be considered. We have evaluated 55 molecules from the perspective of an experienced medicinal chemist as well as using simple molecular properties and have highlighted 16 compounds that have desirable qualities as well as those that may be less desirable. In addition we propose that a collaborative database for sharing such published and novel information on small molecules is needed for the research community studying the Ebola virus.

  14. La respuesta inmune antiviral

    Directory of Open Access Journals (Sweden)

    Rainel Sánchez de la Rosa

    1998-02-01

    Full Text Available Se expone que los virus son parásitos intracelulares obligados, puesto que no tienen metabolismo propio; esto obliga al sistema inmune a poner en marcha sus mecanismos más especializados para reconocer y eliminar, tanto a los virus libres, como a las células infectadas. Se señala que las células presentadoras de antígenos, los linfocitos B y los T unidos al complejo mayor de histocompatibilidad, forman parte de la organización de la respuesta inmune antiviral; la inducción de esta respuesta con proteínas, péptidos y ADN desnudo, son alternativas actuales tanto en la prevención como en el tratamiento de las infecciones viralesIt is explained that viruses are compulsory intracellular parasites, since they don't have their own metabolism, which makes the immune system to start its mest specialized mechanisms to recognize and eliminate the free viruses and the infected cells. It is stated that the cells presenting antigens, and the B and T lymphocytes together with the major histocompatibility complex, are part of the organization of the immune antiviral response. The induction of this response with proteins, peptides and naked DNA are the present alternatives for the prevention and treatment of viral infections

  15. SP-303, an antiviral oligomeric proanthocyanidin from the latex of Croton lechleri (Sangre de Drago).

    Science.gov (United States)

    Ubillas, R; Jolad, S D; Bruening, R C; Kernan, M R; King, S R; Sesin, D F; Barrett, M; Stoddart, C A; Flaster, T; Kuo, J; Ayala, F; Meza, E; Castañel, M; McMeekin, D; Rozhon, E; Tempesta, M S; Barnard, D; Huffman, J; Smee, D; Sidwell, R; Soike, K; Brazier, A; Safrin, S; Orlando, R; Kenny, P T; Berova, N; Nakanishi, K

    1994-09-01

    SP-303, a large proanthocyanidin oligomer isolated from the latex of the plant species Croton lechleri (Eupborbiaceae) has demonstrated broad activity against a variety of DNA and RNA viruses. In cell culture, SP-303 exhibits potent activity against isolates and laboratory strains of respiratory syncytial virus (RSV), influenza A virus (FLU-A) and parainfluenza virus (PIV). Parallel assays of SP-303 and ribavirin showed comparable activity against these viruses. SP-303 also exhibits significant inhibitory activity against herpesvirus (HSV) types 1 and 2, including herpesviruses resistant to acyclovir and foscarnet. Inhibition was also observed against hepatitis A and B viruses. The antiviral mechanism of SP-303 seems to derive from its direct binding to components of the viral envelope, resulting in inhibition of viral attachment and penetration of the plasma membrane. Antiviral effects of SP-303 were measured by three distinct methods: CPE, MTT and precursor uptake/incorporation. Cytotoxicity endpoints were markedly greater than the respective antiviral endpoints. SP-303 exhibited activity in RSV-infected cotton rats and African green monkeys, PIV-3-infected cotton rats, HSV-2 infected mice and guinea pigs and FLU-A-infected mice. The most successful routes of SP-303 administration for producing efficacy were: topical application to HSV-2- genital lesions in mice and guinea pigs, aerosol inhalation to FLU-A-infected mice and PIV-3-infected cotton rats, and oral dosage to RSV-infected cotton rats. A variety of toxicological evaluations demonstrated the safety of SP-303, particularly orally, which was predictable, since condensed tannins are a common dietary component. It is notable that the larger proanthocyanidins as a class have high antiviral activity, whereas most of the monomers are inactive. Clinical trials are ongoing to evaluate SP-303 as a therapeutic antiviral agent.

  16. Phytochemical, antioxidant, antiviral and cytotoxic evaluation of Opuntia dillenii flowers

    OpenAIRE

    Arthanari Saravana Kumar; Mani Ganesh; Mei Mei Peng; Jang Hyun Tae

    2014-01-01

    Opuntia dillenii used in Asian traditional medicine especially in China. We here report on the investigation of the phytochemical content, antioxidant, cytotoxicity and antiviral activity of methanolic extract of O. dillenii flowers. The antioxidant activity was measured with the DPPH, hydrogen peroxide and hydroxyl radicals scavenging method. In the antiviral and cytotoxic assay we used different viruses in different cell lines. In antioxidant assay, the DPPH assay exhibited potent antioxid...

  17. Inactivation of a non-enveloped RNA virus by artificial ribonucleases: honey bees and acute bee paralysis virus as a new experimental model for in vivo antiviral activity assessment.

    Science.gov (United States)

    Fedorova, Antonina A; Azzami, Klara; Ryabchikova, Elena I; Spitsyna, Yulia E; Silnikov, Vladimir N; Ritter, Wolfgang; Gross, Hans J; Tautz, Jürgen; Vlassov, Valentin V; Beier, Hildburg; Zenkova, Marina A

    2011-09-01

    RNA-containing viruses represent a global threat to the health and wellbeing of humans and animals. Hence, the discovery of new approaches for the design of novel vaccines and antiviral compounds attains high attention. Here we describe the potential of artificial ribonucleases (aRNases), low molecular weight compounds capable to cleave phosphodiester bonds in RNA under mild conditions, to act as antiviral compounds via destroying the genome of non-enveloped RNA viruses, and the potential of utilizing honey bee larvae and adult bees (Apis mellifera) as a novel experimental system for the screening of new antiviral compounds. Pre-incubation of an Acute bee paralysis virus (ABPV) suspension with aRNases D3-12, K-D-1 or Dp12F6 in a concentration-dependent manner increased the survival rate of bee larvae and adult bees subsequently infected with these preparations, whereas incubation of the virus with aRNases ABL3C3 or L2-3 had no effect at all. The results of RT-PCR analysis of viral RNA isolated from aRNase-treated virus particles confirmed that virus inactivation occurs via degradation of viral genomic RNA: dose-dependent inactivation of ABPV correlates well with the cleavage of viral RNA. Electron microscopy analysis revealed that the morphology of ABPV particles inactivated by aRNases remains unaffected as compared to control virus preparations. Altogether the obtained results clearly demonstrate the potential of aRNases as a new virus inactivation agents and bee larvae/ABPV as a new in vivo system for the screening of antiviral compounds. Copyright © 2011 Elsevier B.V. All rights reserved.

  18. Antiviral immunity in amphibians.

    Science.gov (United States)

    Chen, Guangchun; Robert, Jacques

    2011-11-01

    Although a variety of virus species can infect amphibians, diseases caused by ranaviruses ([RVs]; Iridoviridae) have become prominent, and are a major concern for biodiversity, agriculture and international trade. The relatively recent and rapid increase in prevalence of RV infections, the wide range of host species infected by RVs, the variability in host resistance among population of the same species and among different developmental stages, all suggest an important involvement of the amphibian immune system. Nevertheless, the roles of the immune system in the etiology of viral diseases in amphibians are still poorly investigated. We review here the current knowledge of antiviral immunity in amphibians, focusing on model species such as the frog Xenopus and the salamander (Ambystoma tigrinum), and on recent progress in generating tools to better understand how host immune defenses control RV infections, pathogenicity, and transmission.

  19. Synthesis, X-ray structure, and hydrolytic chemistry of the high potent antiviral polyniobotungstate A-[alpha]-[Si2Nb6W18O77]8–

    Science.gov (United States)

    Gyu-Shik Kim; Huadong Zeng; Jeffrey T. Rhule; Ira A. Weinstock; Craig L. Hill

    1999-01-01

    Potently antiviral polyniobotungstates have been structurally characterized; the dimer A-[alpha]-[Si2Nb6W18O77]8– cleaves cleanly to the monomer A-[alpha]-[SiNb3W9O40]7– within 1 min in aqueous solution buffered at physiological (neutral) pH establishing that the monomer and not the dimer is pharmacologically relevant.

  20. Dynamic changes in CD45RA−Foxp3high regulatory T-cells in chronic hepatitis C patients during antiviral therapy

    OpenAIRE

    Zhiqin Li; Yu Ping; Zujiang Yu; Meng Wang; Dongli Yue; Zhen Zhang; Jianbin Li; Bin Zhang; Xuezhong Shi; Yi Zhang

    2016-01-01

    Objectives: CD4+Foxp3+ regulatory T-cells (Treg) are known to accumulate under certain pathological conditions. This study was conducted to evaluate the characteristics of and dynamic changes in Treg cells in chronic hepatitis C (CHC) patients during antiviral therapy. Methods: One hundred and forty-five subjects were enrolled in this study, including 105 CHC patients and 40 healthy donors. The phenotypes and functions of Treg cells were analyzed by flow cytometry. Results: A significan...

  1. Metabolism of phosphatidylinositol 4-kinase IIIα-dependent PI4P Is subverted by HCV and is targeted by a 4-anilino quinazoline with antiviral activity.

    Directory of Open Access Journals (Sweden)

    Annalisa Bianco

    Full Text Available 4-anilino quinazolines have been identified as inhibitors of HCV replication. The target of this class of compounds was proposed to be the viral protein NS5A, although unequivocal proof has never been presented. A 4-anilino quinazoline moiety is often found in kinase inhibitors, leading us to formulate the hypothesis that the anti-HCV activity displayed by these compounds might be due to inhibition of a cellular kinase. Type III phosphatidylinositol 4-kinase α (PI4KIIIα has recently been identified as a host factor for HCV replication. We therefore evaluated AL-9, a compound prototypical of the 4-anilino quinazoline class, on selected phosphatidylinositol kinases. AL-9 inhibited purified PI4KIIIα and, to a lesser extent, PI4KIIIβ. In Huh7.5 cells, PI4KIIIα is responsible for the phosphatidylinositol-4 phosphate (PI4P pool present in the plasma membrane. Accordingly, we observed a gradual decrease of PI4P in the plasma membrane upon incubation with AL-9, indicating that this agent inhibits PI4KIIIα also in living cells. Conversely, AL-9 did not affect the level of PI4P in the Golgi membrane, suggesting that the PI4KIIIβ isoform was not significantly inhibited under our experimental conditions. Incubation of cells expressing HCV proteins with AL-9 induced abnormally large clusters of NS5A, a phenomenon previously observed upon silencing PI4KIIIα by RNA interference. In light of our findings, we propose that the antiviral effect of 4-anilino quinazoline compounds is mediated by the inhibition of PI4KIIIα and the consequent depletion of PI4P required for the HCV membranous web. In addition, we noted that HCV has a profound effect on cellular PI4P distribution, causing significant enrichment of PI4P in the HCV-membranous web and a concomitant depletion of PI4P in the plasma membrane. This observation implies that HCV--by recruiting PI4KIIIα in the RNA replication complex--hijacks PI4P metabolism, ultimately resulting in a markedly altered

  2. In Vitro Antiviral Activity of Favipiravir (T-705) against Drug-Resistant Influenza and 2009 A(H1N1) Viruses▿

    OpenAIRE

    Sleeman, Katrina; Mishin, Vasiliy P.; Deyde, Varough M.; Furuta, Yousuke; Klimov, Alexander I.; Gubareva, Larisa V.

    2010-01-01

    Favipiravir (T-705) has previously been shown to have a potent antiviral effect against influenza virus and some other RNA viruses in both cell culture and in animal models. Currently, favipiravir is undergoing clinical evaluation for the treatment of influenza A and B virus infections. In this study, favipiravir was evaluated in vitro for its ability to inhibit the replication of a representative panel of seasonal influenza viruses, the 2009 A(H1N1) strains, and animal viruses with pandemic ...

  3. Oyster viperin retains direct antiviral activity and its transcription occurs via a signalling pathway involving a heat-stable haemolymph protein.

    Science.gov (United States)

    Green, Timothy J; Speck, Peter; Geng, Lu; Raftos, David; Beard, Michael R; Helbig, Karla J

    2015-12-01

    Little is known about the response of non-model invertebrates, such as oysters, to virus infection. The vertebrate innate immune system detects virus-derived nucleic acids to trigger the type I IFN pathway, leading to the transcription of hundreds of IFN-stimulated genes (ISGs) that exert antiviral functions. Invertebrates were thought to lack the IFN pathway based on the absence of IFN or ISGs encoded in model invertebrate genomes. However, the oyster genome encodes many ISGs, including the well-described antiviral protein viperin. In this study, we characterized oyster viperin and showed that it localizes to caveolin-1 and inhibits dengue virus replication in a heterologous model. In a second set of experiments, we have provided evidence that the haemolymph from poly(I : C)-injected oysters contains a heat-stable, protease-susceptible factor that induces haemocyte transcription of viperin mRNA in conjunction with upregulation of IFN regulatory factor. Collectively, these results support the concept that oysters have antiviral systems that are homologous to the vertebrate IFN pathway.

  4. Original Inventions based on Chemical scaffolds and electro-physical activity-derived biosimilars interacting with specialties in biology yielding platforms for analysis in virology and antiviral compounds

    Directory of Open Access Journals (Sweden)

    Yamaji N

    2014-11-01

    line. Mebiol Gel based hepatocytes had better differentiation and the cells were susceptible to hepatitis C virus replication. The Mebiol Gel based 3D culture system can be used as a better cell culture system for viral studies. Potential Solutions: The works presented in the IIDIAS session have portrayed that original invention in any field when subjected to multi-disciplinary interaction after carefully evaluating the potentials can lead to novel solutions. Though the experts in various disciplines in the reported work have got to interact by chance or due to geographical proximity to each other, when a networking platform to throw such ideas to a forum with mutually rewarding opportunities given for discussion and planning of interactive researches is made possible, novel solutions may not be impossible, if the target platform is well understood within the limitations of each stake holder. Creation of a niche or a suitable environment for such multi disciplinary interaction may prevail and work to its best in a physical state of interaction but advances in information technology has broken the need for such physical interaction among peers to bring out novel solutions. Interactions across specialties in the IIDIAS session help in identifying roles for the invention in other fields which may not be directly related to healthcare. The probable solutions and advantages by combining the electro-physical activity-derived biosimilar and the chemically synthesized polymer described in the study include: A novel platform for in vitro culture of HCV having been described, similar platforms for not so easily cultivable viruses can also be developed. The 3D viral culture technology can be exploited to study the replication process and other intricacies of the virus in in vitro culture. When in vitro expansion of viruses in an appropriate manner becomes feasible, anti-viral agents, either virostatic or virucidal, herbal or synthetic biosimilars can be analysed to come out with

  5. 鸭β-防御素16的分离、鉴定及其抗病毒机制%Isolation, Characterization and Mechanism of Anti-viral Activity of Duck Avian Beta-defensin 16

    Institute of Scientific and Technical Information of China (English)

    张可心; 张名岳; 辛胜男; 韩宗玺; 邵昱昊; 刘胜旺; 马得莹

    2012-01-01

    . [Result] Duck AvBD16 consisted of 155 bp encoding 50 amino acids and shared an amino acid homology (62%) with chicken AvBD3. Both recombinant and synthetic duck AvBD16 showed similar antibacterial activities. In high salt ions conditions, antibacterial activity of duck AvBD16 protein was decreased. In addition, the hemolysis activity of the peptide was extremely low. The duck AvBD16 exhibited significant antiviral activity against DHV in vitro. The mRNA expression of AvBD16 and TLR-7 in most tissues, including immune organs and liver, was upregulated or induced in response to DHV infection at different time points. [Conclusion] The duck AvBD16 gene from duck was successfully cloned, expressed in E. call, and recombinant and synthetic AvBD16 protein showed antimicrobial activity and has no hemolytic properties. Duck AvBD16 exhibits significant antiviral activity against DHV in vitro. This result suggests that the antiviral activity against DHV of the AvBD16 is partially via a TLR7-dependent mechanism.

  6. Myxoma Virus dsRNA Binding Protein M029  Inhibits the Type I IFN-Induced Antiviral State in a  Highly Species-Specific Fashion.

    Science.gov (United States)

    Rahman, Masmudur M; McFadden, Grant

    2017-02-02

    Myxoma virus (MYXV) is Leporipoxvirus that possesses a specific rabbit-restricted host tropism but exhibits a much broader  cellular host range in cultured cells. MYXV is able to efficiently  block all aspects of the type I interferon (IFN)-induced  antiviral  state  in rabbit cells, partially in  human  cells  and  very  poorly  in  mouse  cells.  The mechanism(s) of this species-specific inhibition of  type I IFN-induced antiviral state is not well understood. Here we demonstrate that MYXV encoded  protein  M029, a truncated relative of the vaccinia virus (VACV) E3 double-stranded RNA (dsRNA)  binding  protein  that  inhibits  protein  kinase  R (PKR),  can  also  antagonize the type I IFN-induced  antiviral state in a highly species-specific manner. In cells pre-treated with type I IFN prior to  infection,  MYXV  exploits  M029  to  overcome  the  induced  antiviral  state completely in rabbit cells,  partially  in  human  cells,  but  not at all in mouse cells. However, in cells pre-infected with MYXV,  IFN-induced  signaling  is fully  inhibited  even  in the  absence  of M029 in cells from all three species,  suggesting  that  other  MYXV  protein(s)  apart  from  M029  block  IFN  signaling  in  a  speciesindependent  manner.  We  also  show  that  the  antiviral  state  induced in rabbit, human or mouse cells  by  type  I IFN  can  inhibit M029-knockout MYXV even when PKR is genetically knocked-out, suggesting  that  M029  targets  other  host  proteins  for  this  antiviral state inhibition. Thus, the MYXV  dsRNA  binding  protein  M029  not  only  antagonizes  PKR  from  multiple  species  but  also blocks the  type I IFN antiviral state independently of PKR in a highly species-specific fashion.

  7. Myxoma Virus dsRNA Binding Protein M029  Inhibits the Type I IFN‐Induced Antiviral State in a  Highly Species‐Specific Fashion

    Directory of Open Access Journals (Sweden)

    Masmudur M. Rahman

    2017-02-01

    Full Text Available Myxoma virus (MYXV is Leporipoxvirus that possesses a specific rabbit‐restricted host tropism but exhibits a much broader  cellular host range in cultured cells. MYXV is able to efficiently  block all aspects of the type I interferon (IFN‐induced  antiviral  state  in rabbit cells, partially in  human  cells  and  very  poorly  in  mouse  cells.  The mechanism(s of this species‐specific inhibition of  type I IFN‐induced antiviral state is not well understood. Here we demonstrate that MYXV encoded  protein  M029, a truncated relative of the vaccinia virus (VACV E3 double‐stranded RNA (dsRNA  binding  protein  that  inhibits  protein  kinase  R (PKR,  can  also  antagonize the type I IFN‐induced  antiviral state in a highly species‐specific manner. In cells pre‐treated with type I IFN prior to  infection,  MYXV  exploits  M029  to  overcome  the  induced  antiviral  state completely in rabbit cells,  partially  in  human  cells,  but  not at all in mouse cells. However, in cells pre‐infected with MYXV,  IFN‐induced  signaling  is fully  inhibited  even  in the  absence  of M029 in cells from all three species,  suggesting  that  other  MYXV  protein(s  apart  from  M029  block  IFN  signaling  in  a  speciesindependent  manner.  We  also  show  that  the  antiviral  state  induced in rabbit, human or mouse cells  by  type  I IFN  can  inhibit M029‐knockout MYXV even when PKR is genetically knocked‐out, suggesting  that  M029  targets  other  host  proteins  for  this  antiviral state inhibition. Thus, the MYXV  dsRNA  binding  protein  M029  not  only  antagonizes  PKR  from  multiple  species  but  also blocks the  type I IFN antiviral state independently of PKR in a highly species‐specific fashion.

  8. A quantitative measurement of antiviral activity of anti-human immunodeficiency virus type 1 drugs against simian immunodeficiency virus infection: dose-response curve slope strongly influences class-specific inhibitory potential.

    Science.gov (United States)

    Deng, Kai; Zink, M Christine; Clements, Janice E; Siliciano, Robert F

    2012-10-01

    Simian immunodeficiency virus (SIV) infection in macaques is so far the best animal model for human immunodeficiency virus type 1 (HIV-1) studies, but suppressing viral replication in infected animals remains challenging. Using a novel single-round infectivity assay, we quantitated the antiviral activities of antiretroviral drugs against SIV. Our results emphasize the importance of the dose-response curve slope in determining the inhibitory potential of antiretroviral drugs and provide useful information for regimen selection in treating SIV-infected animals in models of therapy and virus eradication.

  9. Anti-infective activities of Pelargonium sidoides (EPS® 7630): effects of induced NO production on Leishmania major in infected macrophages and antiviral effects as assessed in a fibroblast-virus protection assay.

    Science.gov (United States)

    Thäle, Carsten; Kiderlen, Albrecht Ferdinand; Kolodziej, Herbert

    2011-05-01

    EPs® 7630 is an aqueous-ethanolic extract of the roots of Pelargonium sidoides, employed in the treatment of upper respiratory tract infections. Its anti-infective activity is supposed to be associated with the activation of the nonspecific immune system. Using Leishmania major GFP-infected murine BMMΦ, the NO production of EPs® 7630-activated macrophages was correlated with the reduction of the GFP signal measured at single cell levels using flow cytometry. The anti-infectious effect of EPs® 7630 (3-10 µg/mL) on its own (NO production: 4-13 µM; signal reduction: 25-73 %) was less prominent than that in combination with IFN- γ (100 U/mL) (NO production: 20-27 µM; signal reduction: 35-78 %). Furthermore, supernatants of EPs® 7630-stimulated BMMΦ (10 µg/mL) significantly reduced the cytopathic effect of EMCV on L929 fibroblasts (antiviral activity 80 U/mL) when compared with an IFN- γ standard (100 U/mL). Direct addition of EPs® 7630 to L929 did not mediate cytoprotective effects. The antiviral components induced in BMMΦ by EPs® 7630 remain to be identified. Detection of any IFNs by ELISA was unsuccessful, which may be due to their very low concentrations in cell supernatants. The current data provide convincing support for the induction of anti-infectious responses by EPs® 7630.

  10. Natural Products as Source of Potential Dengue Antivirals

    Directory of Open Access Journals (Sweden)

    Róbson Ricardo Teixeira

    2014-06-01

    Full Text Available Dengue is a neglected disease responsible for 22,000 deaths each year in areas where it is endemic. To date, there is no clinically approved dengue vaccine or antiviral for human beings, even though there have been great efforts to accomplish these goals. Several approaches have been used in the search for dengue antivirals such as screening of compounds against dengue virus enzymes and structure-based computational discovery. During the last decades, researchers have turned their attention to nature, trying to identify compounds that can be used as dengue antivirals. Nature represents a vast reservoir of substances that can be explored with the aim of discovering new leads that can be either used directly as pharmaceuticals or can serve as lead structures that can be optimized towards the development of new antiviral agents against dengue. In this review we describe an assortment of natural products that have been reported as possessing dengue antiviral activity. The natural products are organized into classes of substances. When appropriate, structure-activity relationships are outlined. The biological assays used to assess antiviral activity are briefly described.

  11. Exploiting Genetic Interference for Antiviral Therapy.

    Science.gov (United States)

    Tanner, Elizabeth J; Kirkegaard, Karla A; Weinberger, Leor S

    2016-05-01

    Rapidly evolving viruses are a major threat to human health. Such viruses are often highly pathogenic (e.g., influenza virus, HIV, Ebola virus) and routinely circumvent therapeutic intervention through mutational escape. Error-prone genome replication generates heterogeneous viral populations that rapidly adapt to new selection pressures, leading to resistance that emerges with treatment. However, population heterogeneity bears a cost: when multiple viral variants replicate within a cell, they can potentially interfere with each other, lowering viral fitness. This genetic interference can be exploited for antiviral strategies, either by taking advantage of a virus's inherent genetic diversity or through generating de novo interference by engineering a competing genome. Here, we discuss two such antiviral strategies, dominant drug targeting and therapeutic interfering particles. Both strategies harness the power of genetic interference to surmount two particularly vexing obstacles-the evolution of drug resistance and targeting therapy to high-risk populations-both of which impede treatment in resource-poor settings.