scholarly journals An Historic Overview of Biological Response Modifiers as Antiviral Agents

1992 ◽  
Vol 3 (suppl b) ◽  
pp. 34-40 ◽  
Author(s):  
Page S Morahan ◽  
Aangelo J Pinto
Keyword(s):  
Antiviral Activity ◽  
Broad Spectrum ◽  
Antiviral Agents ◽  
Biological Response ◽  
Natural Resistance ◽  
Biological Response Modifiers ◽  
Protective Effects ◽  
Small Molecular Weight

A wide variety ofimmunomodulators/biological response modifiers (BRMs) has been demonstrated to provide broad spectrum antiviral activity against both RNA and DNA viruses in several animal species. Dramatic decreases in mortality, reduced virus titres in tissues and reduced histopathology can be produced. The antivirally effective agents include microbially derived materials, polyanions, cytokines and chemically diverse small molecular weight chemicals. The greatest protective effects are observed with prophylactic treatment. although early therapeutic treatment can also be effective. Little direct antiviral activity can be observed in vitro. The findings suggest induction by BRMs of antiviral mediators in vivo early in the course of viral pathogenesis, before the virus has become sequestered in a privileged site or too much infectious virus has been produced for natural resistance to have an impact, immunomodulators are pleiotropic in their immunomodulatory effects, and it has been difficult to establish whether one cell type or mediator is critical for the observed broad spectrum antiviral activity. Therefore, the mechanisms of antiviral action of immunomodulators remain unclear for most systems, but probably involve enhancement of natural immune responses. While no unified antiviral mechanism among different immunomodulators has yet emerged, interferon induction remains a major hypothesis.

scholarly journals Broad-Spectrum Antiviral Activity of 3’-Deoxy-3’-Fluoroadenosine against Emerging Flaviviruses

2020 ◽  
Author(s):  
Luděk Eyer ◽  
Pavel Svoboda ◽  
Jan Balvan ◽  
Tomáš Vičar ◽  
Matina Raudenská ◽  
...  
Keyword(s):  
Antiviral Activity ◽  
Broad Spectrum ◽  
Nucleotide Metabolism ◽  
Modified Nucleosides ◽  
Bioactive Molecules ◽  
Nucleoside Analogues ◽  
Phase Imaging ◽  
Structural And Functional Properties

Emerging flaviviruses are causative agents of severe and life-threatening diseases, against which no approved therapies are available. Among the nucleoside analogues, which represent a promising group of potentially therapeutic compounds, fluorine-substituted nucleosides are characterized by unique structural and functional properties. Despite having been first synthesized almost 5 decades ago, they still offer new therapeutic opportunities as inhibitors of essential viral or cellular enzymes active in nucleic acid replication/transcription or nucleoside/nucleotide metabolism. Here we report evaluation of the anti-flaviviral activity of 28 nucleoside analogues, each modified with a fluoro substituent at different positions of the ribose ring and/or heterocyclic nucleobase. Our antiviral screening revealed that 3′-deoxy-3′-fluoroadenosine exerted a low-micromolar antiviral effect against tick-borne encephalitis virus (TBEV), Zika virus, and West Nile (WNV) virus (EC50 values from 1.1 ± 0.1 μM to 4.7 ± 1.5 μM), which was manifested in host cell lines of neural and extraneural origin. The compound did not display any measurable cytotoxicity up to concentrations of 25 μM but had an observable cytostatic effect, resulting in suppression of cell proliferation at concentrations of >12.5 μM. Novel approaches based on quantitative phase imaging using holographic microscopy were developed for advanced characterization of antiviral and cytotoxic profiles of 3′-deoxy-3′-fluoroadenosine in vitro. In addition to its antiviral activity in cell cultures, 3′-deoxy-3′-fluoroadenosine was active in vivo in mouse models of TBEV and WNV infection. Our results demonstrate that fluoro-modified nucleosides represent a group of bioactive molecules with excellent potential to serve as prospective broad-spectrum antivirals in antiviral research and drug development.

scholarly journals Amphipathic DNA Polymers Exhibit Antiherpetic Activity In Vitro and In Vivo

2008 ◽  
Vol 52 (8) ◽  
pp. 2727-2733 ◽  
Author(s):  
David I. Bernstein ◽  
Nathalie Goyette ◽  
Rhonda Cardin ◽  
Earl R. Kern ◽  
Guy Boivin ◽  
...  
Keyword(s):  
Antiviral Activity ◽  
Broad Spectrum ◽  
Parent Compound ◽  
Human Herpesvirus ◽  
Varicella Zoster ◽  
Barr Virus ◽  
Simplex Virus ◽  
Acid Stable

ABSTRACT Phosphorothioated oligonucleotides have a sequence-independent antiviral activity as amphipathic polymers (APs). The activity of these agents against herpesvirus infections in vitro and in vivo was investigated. The previously established sequence-independent, phosphorothioation-dependent antiviral activity of APs was confirmed in vitro by showing that a variety of equivalently sized homo- and heteropolymeric AP sequences were similarly active against herpes simplex virus type 1 (HSV-1) infection in vitro compared to the 40mer degenerate parent compound (REP 9), while the absence of phosphorothioation resulted in the loss of antiviral activity. In addition, REP 9 demonstrated in vitro activity against a broad spectrum of other herpesviruses: HSV-2 (50% effective concentration [EC50], 0.02 to 0.06 μM), human cytomegalovirus (EC50, 0.02 to 0.13 μM), varicella zoster virus (EC50, <0.02 μM), Epstein-Barr virus (EC50, 14.7 μM) and human herpesvirus types 6A/B (EC50, 2.9 to 10.2 μM). The murine microbicide model of genital HSV-2 was then used to evaluate in vivo activity. REP 9 (275 mg/ml) protected 75% of animals from disease and infection when provided 5 or 30 min prior to vaginal challenge. When an acid-stable analog (REP 9C) was used, 75% of mice were protected when treated with 240 mg/ml 5 min prior to infection (P < 0.001), while a lower dose (100 mg/ml) protected 100% of the mice (P < 0.001). The acid stable REP 9C formulation also provided protection at 30 min (83%, P < 0.001) and 60 min (50%, P = 0.07) against disease. These observations suggest that APs may have microbicidal activity and potential as broad-spectrum antiherpetic agents and represent a novel class of agents that should be studied further.

scholarly journals Broad-spectrum virucidal activity of bacterial secreted lipases against flaviviruses, SARS-CoV-2 and other enveloped viruses

2020 ◽  
Author(s):  
Xi Yu ◽  
Liming Zhang ◽  
Liangqin Tong ◽  
Nana Zhang ◽  
Han Wang ◽  
...  
Keyword(s):  
Broad Spectrum ◽  
Lipase Activity ◽  
Antiviral Agents ◽  
Antiviral Drug ◽  
Viral Envelope ◽  
Global Public Health ◽  
Virucidal Activity ◽  
Extracellular Milieu

AbstractViruses are the major aetiological agents of acute and chronic severe human diseases that place a tremendous burden on global public health and economy; however, for most viruses, effective prophylactics and therapeutics are lacking, in particular, broad-spectrum antiviral agents. Herein, we identified 2 secreted bacterial lipases from a Chromobacterium bacterium, named Chromobacterium antiviral effector-1 (CbAE-1) and CbAE-2, with a broad-spectrum virucidal activity against dengue virus (DENV), Zika virus (ZIKV), severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), human immunodeficiency virus (HIV) and herpes simplex virus (HSV). The CbAEs potently blocked viral infection in the extracellular milieu through their lipase activity. Mechanistic studies showed that this lipase activity directly disrupted the viral envelope structure, thus inactivating infectivity. A mutation of CbAE-1 in its lipase motif fully abrogated the virucidal ability. Furthermore, CbAE-2 presented low toxicity in vivo and in vitro, highlighting its potential as a broad-spectrum antiviral drug.

Antiviral activities of pyridine fused and pyridine containing heterocycles, a review (From 2000 to 2020)

2021 ◽  
Vol 21 ◽  
Author(s):  
Seyedeh Roya Alizadeh ◽  
Mohammad Ali Ebrahimzadeh
Keyword(s):  
Antiviral Activity ◽  
Biological Activities ◽  
Critical Role ◽  
Antiviral Agents ◽  
Rnase H ◽  
Pyridine Derivatives ◽  
Action Mechanism ◽  
Syncytial Virus

: Heterocyclic compounds play a critical role in medicinal chemistry and many available drugs contain heterocyclic rings. A six-membered heterocyclic compound pyridine showed various applications that acts as an important solvent, reagent, and precursor in agrochemicals and pharmaceuticals. Due to the increase of drug resistance, there is an obvious medical need to develop new antiviral agents. Various derivatives of pyridine scaffold display abroad biological activities such as anti-microbial, anti-viral, antioxidant, anti-diabetic, anti-cancer, anti-malaria, analgesic and anti-inflammatory activities, psychopharmacological antagonistic, anti-amoebic agents, and anti-thrombic activity. Due to the high importance of pyridine derivatives, in the present review, we tried to collect and classify many pyridine derivatives based on their structures from 2000 to 2020. Pyridine derivatives were classified into two general categories including pyridine containing heterocycles and pyridine fused rings. Structure-activity relationship (SAR) and the action mechanism of derivatives were also investigated. According to the recent studies, these derivatives exhibited good antiviral activity against different types of viruses such as the human immunodeficiency viruses (HIV), the hepatitis C virus (HCV), the hepatitis B virus (HBV), Respiratory syncytial virus (RSV), and Cytomegalovirus (CMV). These derivatives inhibited viral application with different action mechanism such as RT inhibition, polymerase inhibition, Inhibition of RNase H activity, inhibition of maturation, inhibition of the viral thymidine kinase, AAK1 (Adaptor-Associated Kinase 1) inhibition, GAK (Cyclin G-associated kinase) inhibition, inhibition of post-integrational event, inhibition of HDAC6, CCR5 antagonistic activity, DNA and RNA replication inhibition, gene expression inhibition, cellular NF-jB signaling pathway and neuraminidase (NA) inhibition, protein synthesis inhibition, and generally inhibition of viral replication cycle. This paper summarily expressed the past and present results about the discovery of novel lead compounds with good antiviral activity. Studies exhibited that almost all of the evaluations were performed by way of in vitro testing and is necessary to investigate in vivo and clinical testing for having better evaluations in the future. We believe that pyridine derivatives can be used as promising antiviral agents and needs to perform more broad investigations in this field.

scholarly journals Biological Response Modifiers and Parasitic Infections: Experimental Aspects of Toxoplasmosis

1994 ◽  
Vol 5 (suppl a) ◽  
pp. 47A-50A
Author(s):  
Miles H Beaman
Keyword(s):  
Critical Role ◽  
Biological Response ◽  
Biological Response Modifiers ◽  
Toxoplasmic Encephalitis ◽  
Current Therapy ◽  
Mouse Strains ◽  
Parasitic Infections ◽  
Ifn Γ

Parasitic infections are important causes of disease in the developing world and, since the advent of AIDS, the developed world. Over the past decade, in vitro and in vivo studies have established the important role that biological response modifiers play in pathogenesis of parasitic disease. These basic studies have resulted in successful clinical trials of interferon gamma (IFN-γ) in human leishmaniasis. Toxoplasmic encephalitis is a major opportunistic infection in patients with AIDS. and current therapy is often problematic. IFN-γ has been shown in in vitro and in vivo animal studies to be critical for host defence against Toxoplasma gondii. Tumour necrosis factor alpha plays a critical role in mediating IFN-γ effect in vitro, but its role in vivo is under further study. lnterleukin (1L)-6 and IL-10 have both recently been shown to enhance T gondii replication in vitro and to antagonize the beneficial effects of IPN-γ. In addition, in certain mouse strains. IL-6 has been shown to worsen mortality from T gondii infection. Future strategies for therapy of T gondii may include administration of exogenous IFN-γ or IL-12 with or without antibody to antagonistic cytokines such as IL-6 (or possibly IL-10).

scholarly journals Nitazoxanide and JIB-04 have broad-spectrum antiviral activity and inhibit SARS-CoV-2 replication in cell culture and coronavirus pathogenesis in a pig model

2020 ◽  
Author(s):  
Juhee Son ◽  
Shimeng Huang ◽  
Qiru Zeng ◽  
Traci L. Bricker ◽  
James Brett Case ◽  
...  
Keyword(s):  
Antiviral Activity ◽  
Body Weight Gain ◽  
Antiviral Agents ◽  
Cell Types ◽  
Respiratory Syndrome Virus ◽  
Transmissible Gastroenteritis Virus ◽  
Global Public Health ◽  
Dna And Rna

AbstractPathogenic coronaviruses represent a major threat to global public health. Here, using a recombinant reporter virus-based compound screening approach, we identified several small-molecule inhibitors that potently block the replication of the newly emerged severe acute respiratory syndrome virus 2 (SARS-CoV-2). Two compounds, nitazoxanide and JIB-04 inhibited SARS-CoV-2 replication in Vero E6 cells with an EC50 of 4.90 μM and 0.69 μM, respectively, with specificity indices of greater than 150. Both inhibitors had in vitro antiviral activity in multiple cell types against some DNA and RNA viruses, including porcine transmissible gastroenteritis virus. In an in vivo porcine model of coronavirus infection, administration of JIB-04 reduced virus infection and associated tissue pathology, which resulted in improved body weight gain and survival. These results highlight the potential utility of nitazoxanide and JIB-04 as antiviral agents against SARS-CoV-2 and other viral pathogens.

scholarly journals NASA GeneLab Platform Utilized for Biological Response to Space Radiation in Animal Models

Cancers ◽  
2020 ◽  
Vol 12 (2) ◽  
pp. 381 ◽  
Author(s):  
J. Tyson McDonald ◽  
Robert Stainforth ◽  
Jack Miller ◽  
Thomas Cahill ◽  
Willian A. da Silveira ◽  
...  
Keyword(s):  
Animal Models ◽  
Radiation Exposure ◽  
Biological Response ◽  
Galactic Cosmic Rays ◽  
Low Earth Orbit ◽  
Protective Effects ◽  
Biological Responses ◽  
Spaceflight Experiments

Background: Ionizing radiation from galactic cosmic rays (GCR) is one of the major risk factors that will impact the health of astronauts on extended missions outside the protective effects of the Earth’s magnetic field. The NASA GeneLab project has detailed information on radiation exposure using animal models with curated dosimetry information for spaceflight experiments. Methods: We analyzed multiple GeneLab omics datasets associated with both ground-based and spaceflight radiation studies that included in vivo and in vitro approaches. A range of ions from protons to iron particles with doses from 0.1 to 1.0 Gy for ground studies, as well as samples flown in low Earth orbit (LEO) with total doses of 1.0 mGy to 30 mGy, were utilized. Results: From this analysis, we were able to identify distinct biological signatures associating specific ions with specific biological responses due to radiation exposure in space. For example, we discovered changes in mitochondrial function, ribosomal assembly, and immune pathways as a function of dose. Conclusions: We provided a summary of how the GeneLab’s rich database of omics experiments with animal models can be used to generate novel hypotheses to better understand human health risks from GCR exposures.

scholarly journals In Vitro Antiviral Activity of Doxycycline against SARS-CoV-2

Molecules ◽  
2020 ◽  
Vol 25 (21) ◽  
pp. 5064 ◽  
Author(s):  
Mathieu Gendrot ◽  
Julien Andreani ◽  
Priscilla Jardot ◽  
Sébastien Hutter ◽  
Océane Delandre ◽  
...  
Keyword(s):  
Antiviral Activity ◽  
Broad Spectrum ◽  
In Vitro Study ◽  
Experimental Models ◽  
In Vivo Evaluation ◽  
Study Results ◽  
Anti Inflammatory ◽  
Approved Drugs

In December 2019, a new severe acute respiratory syndrome coronavirus (SARS-CoV-2), causing coronavirus disease 2019 (COVID-19), emerged in Wuhan, China. Despite containment measures, SARS-CoV-2 spread in Asia, Southern Europe, then in America and currently in Africa. Identifying effective antiviral drugs is urgently needed. An efficient approach to drug discovery is to evaluate whether existing approved drugs can be efficient against SARS-CoV-2. Doxycycline, which is a second-generation tetracycline with broad-spectrum antimicrobial, antimalarial and anti-inflammatory activities, showed in vitro activity on Vero E6 cells infected with a clinically isolated SARS-CoV-2 strain (IHUMI-3) with median effective concentration (EC50) of 4.5 ± 2.9 µM, compatible with oral uptake and intravenous administrations. Doxycycline interacted both on SARS-CoV-2 entry and in replication after virus entry. Besides its in vitro antiviral activity against SARS-CoV-2, doxycycline has anti-inflammatory effects by decreasing the expression of various pro-inflammatory cytokines and could prevent co-infections and superinfections due to broad-spectrum antimicrobial activity. Therefore, doxycycline could be a potential partner of COVID-19 therapies. However, these results must be taken with caution regarding the potential use in SARS-CoV-2-infected patients: it is difficult to translate in vitro study results to actual clinical treatment in patients. In vivo evaluation in animal experimental models is required to confirm the antiviral effects of doxycycline on SARS-CoV-2 and more trials of high-risk patients with moderate to severe COVID-19 infections must be initiated.

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