scholarly journals Carrageenans as Broad-Spectrum Microbicides: Current Status and Challenges

Marine Drugs ◽  
2020 ◽  
Vol 18 (9) ◽  
pp. 435
Author(s):  
Choongho Lee
Keyword(s):  
Broad Spectrum ◽  
Red Algae ◽  
Viral Infections ◽  
Ex Vivo ◽  
Antimicrobial Activities ◽  
Current Status ◽  
Sulfated Polysaccharides ◽  
Future Research

Different kinds of red algae are enriched with chemically diverse carbohydrates. In particular, a group of sulfated polysaccharides, which were isolated from the cell walls of red algae, gained a large amount of attention due to their broad-spectrum antimicrobial activities. Within that group, carrageenans (CGs) were expected to be the first clinically applicable microbicides that could prevent various viral infections due to their superior antiviral potency and desirable safety profiles in subclinical studies. However, their anticipated beneficial effects could not be validated in human studies. To assess the value of a second attempt at pharmacologically developing CGs as a new class of preventive microbicides, all preclinical and clinical development processes of CG-based microbicides need to be thoroughly re-evaluated. In this review, the in vitro toxicities; in vivo safety profiles; and in vitro, ex vivo, and in vivo antiviral activities of CGs are summarized according to the study volume of their target viruses, which include human immunodeficiency virus, herpesviruses, respiratory viruses, human papillomavirus, dengue virus, and other viruses along with a description of their antiviral modes of action and development of antiviral resistance. This evaluation of the strengths and weaknesses of CGs will help provide future research directions that may lead to the successful development of CG-based antimicrobial prophylactics.

scholarly journals Non-Toxic Virucidal Macromolecules Show High Efficacy Against Influenza Virus Ex Vivo and In Vivo

2020 ◽  
Author(s):  
Ozgun Kocabiyik ◽  
Valeria Cagno ◽  
Paulo Jacob Silva ◽  
Yong Zhu ◽  
Laura Sedano ◽  
...  
Keyword(s):  
Broad Spectrum ◽  
Viral Infections ◽  
Ex Vivo ◽  
Public Health Problem ◽  
Major Public Health Problem ◽  
New Class ◽  
Influenza Strain ◽  
Low Toxicity

AbstractInfluenza is one of the most widespread viral infections worldwide and represents a major public health problem. The risk that one of the next pandemics is caused by an influenza strain is very high. It is very important to develop broad-spectrum influenza antivirals to be ready for any possible vaccine shortcomings. Anti-influenza drugs are available but they are far from ideal. Arguably, an ideal antiviral should target conserved viral domains and be virucidal, i.e. irreversibly inhibit viral infectivity. Here, we describe a new class of broad-spectrum anti-influenza macromolecules that meets these criteria and displays exceedingly low toxicity. These compounds are based on a cyclodextrin core modified on its primary face with long hydrophobic linkers terminated in 6’sialyl-N-acetyllactosamine (6’SLN) or 3’SLN. SLN enables nanomolar inhibition of the viruses while the hydrophobic linkers confer irreversibility to the inhibition. The combination of these two properties allows for efficacy in vitro against several human or avian influenza strains, as well as against a 2009 pandemic influenza strain ex vivo. Importantly, we show that, in mice, the compounds provide therapeutic efficacy when administered 24h post-infection allowing 90% survival as opposed to no survival for the placebo and oseltamivir..

scholarly journals Effect of Processing on Fish Protein Antigenicity and Allergenicity

Foods ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 969
Author(s):  
Xingyi Jiang ◽  
Qinchun Rao
Keyword(s):  
Fish Species ◽  
Protein Denaturation ◽  
Ex Vivo ◽  
Protein Solubility ◽  
Future Research ◽  
Food Protein ◽  
In Vivo Evaluation ◽  
Fish Allergy

Fish allergy is a life-long food allergy whose prevalence is affected by many demographic factors. Currently, there is no cure for fish allergy, which can only be managed by strict avoidance of fish in the diet. According to the WHO/IUIS Allergen Nomenclature Sub-Committee, 12 fish proteins are recognized as allergens. Different processing (thermal and non-thermal) techniques are applied to fish and fishery products to reduce microorganisms, extend shelf life, and alter organoleptic/nutritional properties. In this concise review, the development of a consistent terminology for studying food protein immunogenicity, antigenicity, and allergenicity is proposed. It also summarizes that food processing may lead to a decrease, no change, or even increase in fish antigenicity and allergenicity due to the change of protein solubility, protein denaturation, and the modification of linear or conformational epitopes. Recent studies investigated the effect of processing on fish antigenicity/allergenicity and were mainly conducted on commonly consumed fish species and major fish allergens using in vitro methods. Future research areas such as novel fish species/allergens and ex vivo/in vivo evaluation methods would convey a comprehensive view of the relationship between processing and fish allergy.

scholarly journals The Characterization of chIFITMs in Avian Coronavirus Infection In Vivo, Ex Vivo and In Vitro

Genes ◽  
2020 ◽  
Vol 11 (8) ◽  
pp. 918
Author(s):  
Angela Steyn ◽  
Sarah Keep ◽  
Erica Bickerton ◽  
Mark Fife
Keyword(s):  
Post Infection ◽  
Viral Infections ◽  
Ex Vivo ◽  
Large Family ◽  
Respiratory Pathogen ◽  
Restriction Factors ◽  
Respiratory Illnesses ◽  
Bird Mortality

The coronaviruses are a large family of enveloped RNA viruses that commonly cause gastrointestinal or respiratory illnesses in the infected host. Avian coronavirus infectious bronchitis virus (IBV) is a highly contagious respiratory pathogen of chickens that can affect the kidneys and reproductive systems resulting in bird mortality and decreased reproductivity. The interferon-inducible transmembrane (IFITM) proteins are activated in response to viral infections and represent a class of cellular restriction factors that restrict the replication of many viral pathogens. Here, we characterize the relative mRNA expression of the chicken IFITM genes in response to IBV infection, in vivo, ex vivo and in vitro using the pathogenic M41-CK strain, the nephropathogenic QX strain and the nonpathogenic Beaudette strain. In vivo we demonstrate a significant upregulation of chIFITM1, 2, 3 and 5 in M41-CK- and QX-infected trachea two days post-infection. In vitro infection with Beaudette, M41-CK and QX results in a significant upregulation of chIFITM1, 2 and 3 at 24 h post-infection. We confirmed a differential innate response following infection with distinct IBV strains and believe that our data provide new insights into the possible role of chIFITMs in early IBV infection.

scholarly journals Modified cyclodextrins as broad-spectrum antivirals

2020 ◽  
Vol 6 (5) ◽  
pp. eaax9318 ◽  
Author(s):  
Samuel T. Jones ◽  
Valeria Cagno ◽  
Matej Janeček ◽  
Daniel Ortiz ◽  
Natalia Gasilova ◽  
...  
Keyword(s):  
Broad Spectrum ◽  
Viral Infections ◽  
Ex Vivo ◽  
Vaginal Tissue ◽  
Modified Cyclodextrins ◽  
Culture Models ◽  
Heparan Sulfates ◽  
Syncytial Virus ◽  
Simplex Virus

Viral infections kill millions of people and new antivirals are needed. Nontoxic drugs that irreversibly inhibit viruses (virucidal) are postulated to be ideal. Unfortunately, all virucidal molecules described to date are cytotoxic. We recently developed nontoxic, broad-spectrum virucidal gold nanoparticles. Here, we develop further the concept and describe cyclodextrins, modified with mercaptoundecane sulfonic acids, to mimic heparan sulfates and to provide the key nontoxic virucidal action. We show that the resulting macromolecules are broad-spectrum, biocompatible, and virucidal at micromolar concentrations in vitro against many viruses [including herpes simplex virus (HSV), respiratory syncytial virus (RSV), dengue virus, and Zika virus]. They are effective ex vivo against both laboratory and clinical strains of RSV and HSV-2 in respiratory and vaginal tissue culture models, respectively. Additionally, they are effective when administrated in mice before intravaginal HSV-2 inoculation. Lastly, they pass a mutation resistance test that the currently available anti-HSV drug (acyclovir) fails.

scholarly journals Current status of in vitro and in vivo antifungal activities of posaconazole

2013 ◽  
Vol 1 (1) ◽  
pp. 18-22
Author(s):  
He Sun ◽  
Xin Su ◽  
Yi Shi
Keyword(s):  
Animal Models ◽  
Broad Spectrum ◽  
Fungal Infections ◽  
Current Status ◽  
Dimorphic Fungi ◽  
Antifungal Activities ◽  
Endemic Fungi ◽  
Yeasts And Molds

Abstract Posaconazole (POS) is a new triazole drug with broad-spectrum in vitro activity against most yeasts and molds such as Candida, Cryptococcus neoformans, Aspergillus, Fusarium and Zygomycetes, as well as certain species of dimorphic fungi and endemic fungi. In immunocompetent or immunocompromised animal models with invasive fungal infections, POS has demonstrated highly effective, broad-spectrum antifungal activities. In vitro and in vivo antifungal activities of POS were superior to those of other azoles against Candida glabrata, Candida krusei, Aspergillus terrus, Fusarium and Zygomycetes. In vivo susceptibility studies have shown promising efficacy of POS against life-threatening fungal infections in animal models with different immune status and infection sites.

HPMPC (cidofovir), PMEA (adefovir) and Related Acyclic Nucleoside Phosphonate Analogues: A Review of their Pharmacology and Clinical Potential in the Treatment of Viral Infections

1997 ◽  
Vol 8 (1) ◽  
pp. 1-23 ◽  
Author(s):  
L Naesens ◽  
R Snoeck ◽  
G Andrei ◽  
J Balzarini ◽  
J Neyts ◽  
...  
Keyword(s):  
Broad Spectrum ◽  
Viral Infections ◽  
Specific Interaction ◽  
Hiv Infections ◽  
Concomitant Administration ◽  
Varicella Zoster ◽  
Acyclic Nucleoside ◽  
Acyclic Nucleoside Phosphonate

The acyclic nucleoside phosphonate (ANP) analogues are broad-spectrum antiviral agents, with potent and selective antiviral activity in vitro and in vivo. The prototype compounds are: ( S)-1-(3-hydroxy-2-phosphonylmethoxypropyl)cytosine (HPMPC, cidofovir), which is active against a wide variety of DNA viruses; 9-(2-phosphonylmethoxyethyl)adenine (PMEA, adefovir), which is active against retro-, herpes- and hepadnaviruses, and ( R)-9-(2-phosphonylmethoxypropyl) adenine (PMPA), which is active against retro- and hepadnaviruses. The antiviral action of the ANP analogues is based on a specific interaction of the active diphosphorylated metabolite with the viral DNA polymerase. The long intracellular half-life of the active metabolite accounts for the optimal efficacy in infrequent dosing schedules. The potential of HPMPC as a broad-spectrum anti-DNA virus agent, as originally observed in vitro and in vivo, has been confirmed in clinical trials. HPMPC has recently been commercially released in the USA for the treatment of cytomegalovirus retinitis in AIDS patients. In addition, topical systemic HPMPC is being (or will be) explored for use against other herpesviruses (i.e. herpes simplex virus, Epstein-Barr virus, or varicella-zoster virus), by adenoviruses, or by human papilloma- or polyomaviruses. Intravenous HPMPC is associated with dose-dependent nephrotoxicity, that should be counteracted by prehydration and concomitant administration of probenecid, and by the application of an infrequent dosing schedule. The oral prodrug of PMEA, bis(pivaloyloxymethyl)-PMEA, is currently being evaluated in patients infected with human immunodeficiency virus (HIV) or hepatitis B virus. Finally, preclinical data on the efficacy of PMPA in animal retrovirus models point to its potential usefulness against HIV infections, when given either prophylactically or therapeutically in the treatment of established HIV infections.

In Vitro and Ex Vivo Studies of Antioxidant Activity of Carrageenans, Sulfated Polysaccharides from Red Algae

2011 ◽  
Vol 150 (4) ◽  
pp. 426-428 ◽  
Author(s):  
E. V. Sokolova ◽  
A. O. Barabanova ◽  
V. A. Homenko ◽  
T. F. Solov’eva ◽  
R. N. Bogdanovich ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Red Algae ◽  
Ex Vivo ◽  
Sulfated Polysaccharides

scholarly journals Resveratrol, Rapamycin and Metformin as Modulators of Antiviral Pathways

Viruses ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 1458
Author(s):  
Francesca Benedetti ◽  
Vincenzo Sorrenti ◽  
Alessandro Buriani ◽  
Stefano Fortinguerra ◽  
Giovanni Scapagnini ◽  
...  
Keyword(s):  
Mammalian Cells ◽  
Viral Infections ◽  
Small Animal ◽  
Current Status ◽  
Dietary Interventions ◽  
Antiviral Immune Response ◽  
Small Animal Models ◽  
Cellular Pathways

Balanced nutrition and appropriate dietary interventions are fundamental in the prevention and management of viral infections. Additionally, accurate modulation of the inflammatory response is necessary to achieve an adequate antiviral immune response. Many studies, both in vitro with mammalian cells and in vivo with small animal models, have highlighted the antiviral properties of resveratrol, rapamycin and metformin. The current review outlines the mechanisms of action of these three important compounds on the cellular pathways involved with viral replication and the mechanisms of virus-related diseases, as well as the current status of their clinical use.

Dendritic Cells Efficiently Induce Protective Antiviral Immunity

1998 ◽  
Vol 72 (5) ◽  
pp. 3812-3818 ◽  
Author(s):  
Burkhard Ludewig ◽  
Stephan Ehl ◽  
Urs Karrer ◽  
Bernhard Odermatt ◽  
Hans Hengartner ◽  
...  
Keyword(s):  
Dendritic Cells ◽  
High Speed ◽  
Viral Infections ◽  
Ex Vivo ◽  
Antiviral Immunity ◽  
Recombinant Vaccinia Virus ◽  
Challenge Infection ◽  
Antiviral Immune Response

ABSTRACT Cytotoxic T lymphocytes (CTL) are essential for effective immunity to various viral infections. Because of the high speed of viral replication, control of viral infections imposes demanding functional and qualitative requirements on protective T-cell responses. Dendritic cells (DC) have been shown to efficiently acquire, transport, and present antigens to naive CTL in vitro and in vivo. In this study, we assessed the potential of DC, either pulsed with the lymphocytic choriomeningitis virus (LCMV)-specific peptide GP33-41 or constitutively expressing the respective epitope, to induce LCMV-specific antiviral immunity in vivo. Comparing different application routes, we found that only 100 to 1,000 DC had to reach the spleen to achieve protective levels of CTL activation. The DC-induced antiviral immune response developed rapidly and was long lasting. Already at day 2 after a single intravenous immunization with high doses of DC (1 × 105 to 5 × 105), mice were fully protected against LCMV challenge infection, and direct ex vivo cytotoxicity was detectable at day 4 after DC immunization. At day 60, mice were still protected against LCMV challenge infection. Importantly, priming with DC also conferred protection against infections in which the homing of CTL into peripheral organs is essential: DC-immunized mice rapidly cleared an infection with recombinant vaccinia virus-LCMV from the ovaries and eliminated LCMV from the brain, thereby avoiding lethal choriomeningitis. A comparison of DC constitutively expressing the GP33-41 epitope with exogenously peptide-pulsed DC showed that in vivo CTL priming with peptide-loaded DC is not limited by turnover of peptide-major histocompatibility complex class I complexes. We conclude that the priming of antiviral CTL responses with DC is highly efficient, rapid, and long lasting. Therefore, the use of DC should be considered as an efficient means of immunization for antiviral vaccination strategies.

Nature-derived hit, lead, and drug-like small molecules: Current status and future aspects against key target proteins of Coronaviruses

2021 ◽  
Vol 21 ◽  
Author(s):  
Md. Junaid ◽  
Yeasmin Akter ◽  
Aysha Siddika ◽  
S. M. Abdul Nayeem ◽  
Afsana Nahrin ◽  
...  
Keyword(s):  
Clinical Trial ◽  
Clinical Trials ◽  
Small Molecules ◽  
Current Status ◽  
Future Research ◽  
Literature Study ◽  
Lead Compounds ◽  
Human Coronaviruses

Background: COVID-19 pandemic, the most unprecedented event of the year 2020, has brought millions of scientists worldwide in a single platform to fight against it. Though several drugs are now in the clinical trial, few vaccines available on the market already but the lack of an effect of those is making the situation worse. Aim of the study: In this review, we demonstrated comprehensive data of natural antiviral products showing activities against different proteins of Human Coronaviruses (HCoV) that are responsible for its pathogenesis. Furthermore, we categorized the compounds into the hit, lead, and drug based on the IC50/EC50 value, drug-likeness, and lead-likeness test to portray their potentiality to be a drug. We also demonstrated the present status of our screened antiviral compounds with respect to clinical trials and reported the lead compounds that can be promoted to clinical trial against COVID-19. Methods: A systematic search strategy was employed focusing on Natural Products (NPs) with proven activity (in vitro, in vivo, or in silico) against human coronaviruses, in general, and data were gathered from databases like PubMed, Web of Science, Google Scholar, SciVerse, and Scopus. Information regarding clinical trials retrieved from the Clinical Trial database. Results: Total "245" natural compounds were identified initially from the literature study. Among them, Glycyrrhizin, Caffeic acid, Curcumin is in phase 3, and Tetrandrine, Cyclosporine, Tacrolimus, Everolimus are in phase 4 clinical trial. Except for Glycyrrhizin, all compounds showed activity against COVID-19. Conclusions: In summary, our demonstrated specific small molecules with lead and drug-like capabilities clarified their position in the drug discovery pipeline and proposed their future research against COVID-19.

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