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1.
ACS Appl Mater Interfaces ; 13(14): 16084-16096, 2021 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-33793211

RESUMO

As COVID-19 exemplifies, respiratory diseases transmitted through aerosols or droplets are global threats to public health, and respiratory protection measures are essential first lines of infection prevention and control. However, common face masks are single use and can cause cross-infection due to the accumulated infectious pathogens. We developed salt-based formulations to coat membrane fibers to fabricate antimicrobial filters. Here, we report a mechanistic study on salt-induced pathogen inactivation. The salt recrystallization following aerosol exposure was characterized over time on sodium chloride (NaCl), potassium sulfate (K2SO4), and potassium chloride (KCl) powders and coatings, which revealed that NaCl and KCl start to recrystallize within 5 min and K2SO4 within 15 min. The inactivation kinetics observed for the H1N1 influenza virus and Klebsiella pneumoniae matched the salt recrystallization well, which was identified as the main destabilizing mechanism. Additionally, the salt-coated filters were prepared with different methods (with and without a vacuum process), which led to salt coatings with different morphologies for diverse applications. Finally, the salt-coated filters caused a loss of pathogen viability independent of transmission mode (aerosols or droplets), against both DI water and artificial saliva suspensions. Overall, these findings increase our understanding of the salt-recrystallization-based technology to develop highly versatile antimicrobial filters.


Assuntos
Filtração/instrumentação , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Klebsiella pneumoniae/efeitos dos fármacos , Máscaras , Cloreto de Potássio/química , Cloreto de Sódio/química , Sulfatos/química , Aerossóis , Filtros de Ar , Cristalização , Cinética , Membranas Artificiais , Polipropilenos , Pós , Dispositivos de Proteção Respiratória , Temperatura , Difração de Raios X
2.
Sci Rep ; 11(1): 8692, 2021 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-33888738

RESUMO

A metal nanoparticle composite, namely TPNT1, which contains Au-NP (1 ppm), Ag-NP (5 ppm), ZnO-NP (60 ppm) and ClO2 (42.5 ppm) in aqueous solution was prepared and characterized by spectroscopy, transmission electron microscopy, dynamic light scattering analysis and potentiometric titration. Based on the in vitro cell-based assay, TPNT1 inhibited six major clades of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) with effective concentration within the range to be used as food additives. TPNT1 was shown to block viral entry by inhibiting the binding of SARS-CoV-2 spike proteins to the angiotensin-converting enzyme 2 (ACE2) receptor and to interfere with the syncytium formation. In addition, TPNT1 also effectively reduced the cytopathic effects induced by human (H1N1) and avian (H5N1) influenza viruses, including the wild-type and oseltamivir-resistant virus isolates. Together with previously demonstrated efficacy as antimicrobials, TPNT1 can block viral entry and inhibit or prevent viral infection to provide prophylactic effects against both SARS-CoV-2 and opportunistic infections.


Assuntos
Ouro/farmacologia , Vírus da Influenza A Subtipo H1N1/fisiologia , Virus da Influenza A Subtipo H5N1/fisiologia , Prata/farmacologia , Óxido de Zinco/farmacologia , /metabolismo , Antivirais/química , Antivirais/farmacologia , Farmacorresistência Viral/efeitos dos fármacos , Aditivos Alimentares/farmacologia , Ouro/química , Células HEK293 , Humanos , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Virus da Influenza A Subtipo H5N1/efeitos dos fármacos , Nanopartículas Metálicas/química , Nanocompostos/química , Oseltamivir/farmacologia , Tamanho da Partícula , Ligação Proteica/efeitos dos fármacos , Prata/química , Glicoproteína da Espícula de Coronavírus/metabolismo , Internalização do Vírus/efeitos dos fármacos , Óxido de Zinco/química
3.
BMC Complement Med Ther ; 21(1): 92, 2021 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-33726731

RESUMO

BACKGROUND: Some viruses play a key role in the disturbance of the digestive system. The common viruses which cause infectious diarrhoea (gastroenteritis) include astrovirus, caliciviruses, coronavirus and torovirus which are single-stranded RNA viruses. Influenza A virus (H1N1) also causes diarrhoea in addition to being associated with respiratory symptoms. In preliminary studies, Newtonia hildebrandtii and N. buchananii leaf extracts had good antibacterial activity against some bacteria implicated in causing diarrhoea. The aim of this study was to evaluate the anti-influenza activity of two Newtonia species extracts and the isolated compound (myricitrin). METHODS: N. hildebrandtii and N. buchananii acetone, and MeOH: DCM (methanol-dichloromethane) leaf and stem extracts, and an antibacterial compound myricetin-3-o-rhamnoside (myricitrin), isolated from N. buchananii, were evaluated for their antiviral efficacy against influenza A virus (IAV) PR8/34/H1N1 as a model organism. The MTT and hemagglutination assays were used to assess the extracts and compound interference with cell viability and viral surface HA glycoprotein. The quantitative real-time PCR was performed to assess the viral load. RESULTS: Plant extracts of N. hildebrandtii and N. buchananii were effective against IAV. The extracts in combination with H1N1 showed highly significant antiviral activity (P < 0.01) and maintained cell viabilities (P < 0.05). Myricitrin was non-cytotoxic at concentration 104 µg/ml. Myricitrin was most effective against IAV in a co-penetration combined treatment, thereby confirming the inhibitory effect of this compound in the viral attachment and entry stages. Myricitrin treatment also resulted in the highest viability of the cells in co-penetration treatment. The activity of myricitrin indicates the potential of the extracts in controlling viral infection at the attachment stage. The antiviral effect of myricitrin on IAV load in MDCK cell culture was confirmed using quantitative real-time PCR. CONCLUSION: Data from this study support further research and development on Newtonia hildebrandtii, Newtonia buchananii and myricitrin to address diarrhoea and related conditions caused by viruses in both human and veterinary medicine. Further work needs to be conducted on the activity of the extracts and the purified compound on other viruses of importance which have similar symptoms to influenza virus such as the coronavirus which led to a recent global pandemic.


Assuntos
Antivirais/farmacologia , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Manosídeos/farmacologia , Fitoterapia , Extratos Vegetais/farmacologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Cães , Humanos , Células Madin Darby de Rim Canino/efeitos dos fármacos , Folhas de Planta , Caules de Planta , Reação em Cadeia da Polimerase em Tempo Real
4.
Viruses ; 13(2)2021 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-33546185

RESUMO

The long-term control strategy of SARS-CoV-2 and other major respiratory viruses needs to include antivirals to treat acute infections, in addition to the judicious use of effective vaccines. Whilst COVID-19 vaccines are being rolled out for mass vaccination, the modest number of antivirals in use or development for any disease bears testament to the challenges of antiviral development. We recently showed that non-cytotoxic levels of thapsigargin (TG), an inhibitor of the sarcoplasmic/endoplasmic reticulum (ER) Ca2+ ATPase pump, induces a potent host innate immune antiviral response that blocks influenza A virus replication. Here we show that TG is also highly effective in blocking the replication of respiratory syncytial virus (RSV), common cold coronavirus OC43, SARS-CoV-2 and influenza A virus in immortalized or primary human cells. TG's antiviral performance was significantly better than remdesivir and ribavirin in their respective inhibition of OC43 and RSV. Notably, TG was just as inhibitory to coronaviruses (OC43 and SARS-CoV-2) and influenza viruses (USSR H1N1 and pdm 2009 H1N1) in separate infections as in co-infections. Post-infection oral gavage of acid-stable TG protected mice against a lethal influenza virus challenge. Together with its ability to inhibit the different viruses before or during active infection, and with an antiviral duration of at least 48 h post-TG exposure, we propose that TG (or its derivatives) is a promising broad-spectrum inhibitor against SARS-CoV-2, OC43, RSV and influenza virus.


Assuntos
Antivirais/farmacologia , Betacoronavirus/efeitos dos fármacos , Coronavirus Humano OC43/efeitos dos fármacos , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Vírus Sincicial Respiratório Humano/efeitos dos fármacos , Tapsigargina/farmacologia , Animais , Antivirais/uso terapêutico , Betacoronavirus/fisiologia , Linhagem Celular , Linhagem Celular Tumoral , Células Cultivadas , Coronavirus Humano OC43/fisiologia , Estresse do Retículo Endoplasmático , Humanos , Vírus da Influenza A Subtipo H1N1/fisiologia , Camundongos , Testes de Sensibilidade Microbiana , Infecções por Orthomyxoviridae/tratamento farmacológico , Infecções por Orthomyxoviridae/virologia , Vírus Sincicial Respiratório Humano/fisiologia , Ribavirina/farmacologia , Tapsigargina/uso terapêutico , Replicação Viral/efeitos dos fármacos
5.
Angew Chem Int Ed Engl ; 60(17): 9467-9473, 2021 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-33464672

RESUMO

The search for vaccines that protect from severe morbidity and mortality because of infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus that causes coronavirus disease 2019 (COVID-19) is a race against the clock and the virus. Here we describe an amphiphilic imidazoquinoline (IMDQ-PEG-CHOL) TLR7/8 adjuvant, consisting of an imidazoquinoline conjugated to the chain end of a cholesterol-poly(ethylene glycol) macromolecular amphiphile. It is water-soluble and exhibits massive translocation to lymph nodes upon local administration through binding to albumin, affording localized innate immune activation and reduction in systemic inflammation. The adjuvanticity of IMDQ-PEG-CHOL was validated in a licensed vaccine setting (quadrivalent influenza vaccine) and an experimental trimeric recombinant SARS-CoV-2 spike protein vaccine, showing robust IgG2a and IgG1 antibody titers in mice that could neutralize viral infection in vitro and in vivo in a mouse model.


Assuntos
Adjuvantes Imunológicos/uso terapêutico , /prevenção & controle , Imidazóis/uso terapêutico , Imunidade Inata/efeitos dos fármacos , Quinolinas/uso terapêutico , Animais , Colesterol/análogos & derivados , Colesterol/imunologia , Colesterol/uso terapêutico , Feminino , Humanos , Imidazóis/imunologia , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Vacinas contra Influenza/imunologia , Vacinas contra Influenza/uso terapêutico , Influenza Humana/prevenção & controle , Glicoproteínas de Membrana/agonistas , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Polietilenoglicóis/uso terapêutico , Quinolinas/imunologia , Proteínas Recombinantes/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Tensoativos/uso terapêutico , Receptor 7 Toll-Like/agonistas , Receptor 8 Toll-Like/agonistas
6.
Bioorg Chem ; 107: 104619, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33450541

RESUMO

Severe emerging and re-emerging viral infections such as Lassa fever, Avian influenza (AI), and COVID-19 caused by SARS-CoV-2 urgently call for new strategies for the development of broad-spectrum antivirals targeting conserved components in the virus life cycle. Viral lipids are essential components, and viral-cell membrane fusion is the required entry step for most unrelated enveloped viruses. In this paper, we identified a porphyrin derivative of protoporphyrin IX (PPIX) that showed broad antiviral activities in vitro against a panel of enveloped pathogenic viruses including Lassa virus (LASV), Machupo virus (MACV), and SARS-CoV-2 as well as various subtypes of influenza A viral strains with IC50 values ranging from 0.91 ± 0.25 µM to 1.88 ± 0.34 µM. A mechanistic study using influenza A/Puerto Rico/8/34 (H1N1) as a testing strain showed that PPIX inhibits the infection in the early stage of virus entry through biophysically interacting with the hydrophobic lipids of enveloped virions, thereby inhibiting the entry of enveloped viruses into host cells. In addition, the preliminary antiviral activities of PPIX were further assessed by testing mice infected with the influenza A/Puerto Rico/8/34 (H1N1) virus. The results showed that compared with the control group without drug treatment, the survival rate and mean survival time of the mice treated with PPIX were apparently prolonged. These data encourage us to conduct further investigations using PPIX as a lead compound for the rational design of lipid-targeting antivirals for the treatment of infection with enveloped viruses.


Assuntos
Antivirais/uso terapêutico , Infecções por Orthomyxoviridae/tratamento farmacológico , Protoporfirinas/uso terapêutico , Internalização do Vírus/efeitos dos fármacos , Animais , Antivirais/síntese química , Antivirais/metabolismo , Antivirais/farmacologia , Arenavirus do Novo Mundo/efeitos dos fármacos , Chlorocebus aethiops , Cães , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Vírus Lassa/efeitos dos fármacos , Células Madin Darby de Rim Canino , Masculino , Lipídeos de Membrana/metabolismo , Camundongos , Testes de Sensibilidade Microbiana , Protoporfirinas/síntese química , Protoporfirinas/metabolismo , Protoporfirinas/farmacologia , Células Vero , /efeitos dos fármacos
7.
J Ethnopharmacol ; 264: 112800, 2021 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-32224195

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: The San Wu Huangqin Decoction (SWHD), which is made from the dried root of Sophora flavescens Aiton (Kushen in Chinese), the dried root of Scutellaria baicalensis Georgi (Huangqin in Chinese), and the dried root tuber of Rehmannia glutinosa (Gaertn.) DC. (Dihuang in Chinese), is a traditional Chinese formula used to treat prolonged fever and inflammatory diseases in clinics and proven to inhibit influenza virus effectively in our previous study. AIM OF THE STUDY: This work was performed to study the regulation of SWHD on inflammation and immune dysfunction induced by the influenza virus and the underlying mechanism in the treatment of SWHD. METHODS: In this study, the influenza virus A/PR/8/34 (H1N1)-infected mouse model was used to investigate the regulation of SWHD on inflammation and immune dysfunction induced by H1N1. The pathological changes, the capacity of proliferation of T and B lymphocytes, the cytotoxicity of natural killer (NK) cells, and the levels of IL-6, TNF-α, IL-1ß, IL-4, and IFN-γ in the serum, bronchoalveolar lavage fluid (BALF), and lung were analyzed. The effects of type 1 T helper cell (Th1) and type 2 T helper cell (Th2) immune responses were discussed indirectly. In addition, the expression levels of p-p65, p65, IKKα/ß, p-IκBα, and IκBα in relation to the NF-κB pathway were measured using Western blot analysis, or immunohistochemical assay. RESULTS: SWHD decreased the pathological changes in lung tissues, promoted the proliferation of T and B lymphocytes, enhanced NK cell activity, and accelerated the phagocytic function of macrophages in H1N1-infected mice. At the same time, SWHD decreased the levels of IL-6, TNF-α, IL-1ß, IFN-γ, and increased the level of IL-4 in the serum, BALF, and lung of model mice. Moreover, the p-p65, p65, and IκBα protein expression levels were inhibited, whereas the p-IκBα protein expression levels were improved in the lungs of H1N1-infected mice. CONCLUSIONS: SWHD can inhibit the replication of the H1N1 virus and reduced the excessive inflammation and immune dysfunction induced by the H1N1 virus in the body. This work provides rich experimental basis for further anti-inflammation research of SWHD and sets the foundation for the development of a viral inflammation drug of traditional Chinese medicine.


Assuntos
Antivirais/uso terapêutico , Medicamentos de Ervas Chinesas/uso terapêutico , Imunidade Celular/efeitos dos fármacos , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , NF-kappa B/fisiologia , Infecções por Orthomyxoviridae/tratamento farmacológico , Animais , Antivirais/farmacologia , Relação Dose-Resposta a Droga , Medicamentos de Ervas Chinesas/farmacologia , Feminino , Imunidade Celular/fisiologia , Inflamação/tratamento farmacológico , Inflamação/imunologia , Vírus da Influenza A Subtipo H1N1/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Infecções por Orthomyxoviridae/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia
8.
Front Immunol ; 11: 598444, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33362782

RESUMO

Patients infected with SARS-CoV-2 show a wide spectrum of clinical manifestations ranging from mild febrile illness and cough up to acute respiratory distress syndrome, multiple organ failure, and death. Data from patients with severe clinical manifestations compared to patients with mild symptoms indicate that highly dysregulated exuberant inflammatory responses correlate with severity of disease and lethality. Epithelial-immune cell interactions and elevated cytokine and chemokine levels, i.e. cytokine storm, seem to play a central role in severity and lethality in COVID-19. The present perspective places a central cellular pro-inflammatory signal pathway, NF-κB, in the context of recently published data for COVID-19 and provides a hypothesis for a therapeutic approach aiming at the simultaneous inhibition of whole cascades of pro-inflammatory cytokines and chemokines. The simultaneous inhibition of multiple cytokines/chemokines is expected to have much higher therapeutic potential as compared to single target approaches to prevent cascade (i.e. redundant, triggering, amplifying, and synergistic) effects of multiple induced cytokines and chemokines in critical stage COVID-19 patients.


Assuntos
/tratamento farmacológico , Síndrome da Liberação de Citocina/tratamento farmacológico , NF-kappa B/antagonistas & inibidores , Inibidores de Proteassoma/farmacologia , /efeitos dos fármacos , Animais , /patologia , Síndrome da Liberação de Citocina/patologia , Citocinas/sangue , Modelos Animais de Doenças , Humanos , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Virus da Influenza A Subtipo H5N1/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Infecções por Orthomyxoviridae/tratamento farmacológico , /imunologia
9.
PLoS Pathog ; 16(8): e1008716, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32780760

RESUMO

Pandemic influenza A virus (IAV) remains a significant threat to global health. Preparedness relies primarily upon a single class of neuraminidase (NA) targeted antivirals, against which resistance is steadily growing. The M2 proton channel is an alternative clinically proven antiviral target, yet a near-ubiquitous S31N polymorphism in M2 evokes resistance to licensed adamantane drugs. Hence, inhibitors capable of targeting N31 containing M2 (M2-N31) are highly desirable. Rational in silico design and in vitro screens delineated compounds favouring either lumenal or peripheral M2 binding, yielding effective M2-N31 inhibitors in both cases. Hits included adamantanes as well as novel compounds, with some showing low micromolar potency versus pandemic "swine" H1N1 influenza (Eng195) in culture. Interestingly, a published adamantane-based M2-N31 inhibitor rapidly selected a resistant V27A polymorphism (M2-A27/N31), whereas this was not the case for non-adamantane compounds. Nevertheless, combinations of adamantanes and novel compounds achieved synergistic antiviral effects, and the latter synergised with the neuraminidase inhibitor (NAi), Zanamivir. Thus, site-directed drug combinations show potential to rejuvenate M2 as an antiviral target whilst reducing the risk of drug resistance.


Assuntos
Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Influenza Humana/virologia , Rimantadina/farmacologia , Proteínas da Matriz Viral/antagonistas & inibidores , Zanamivir/farmacologia , Antivirais/farmacologia , Farmacorresistência Viral , Sinergismo Farmacológico , Quimioterapia Combinada , Humanos , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H1N1/metabolismo , Influenza Humana/tratamento farmacológico , Proteínas da Matriz Viral/genética , Proteínas da Matriz Viral/metabolismo
10.
Cell Rep ; 32(6): 108016, 2020 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-32755598

RESUMO

The influenza virus hemagglutinin (HA) and coronavirus spike (S) protein mediate virus entry. HA and S proteins are heavily glycosylated, making them potential targets for carbohydrate binding agents such as lectins. Here, we show that the lectin FRIL, isolated from hyacinth beans (Lablab purpureus), has anti-influenza and anti-SARS-CoV-2 activity. FRIL can neutralize 11 representative human and avian influenza strains at low nanomolar concentrations, and intranasal administration of FRIL is protective against lethal H1N1 infection in mice. FRIL binds preferentially to complex-type N-glycans and neutralizes viruses that possess complex-type N-glycans on their envelopes. As a homotetramer, FRIL is capable of aggregating influenza particles through multivalent binding and trapping influenza virions in cytoplasmic late endosomes, preventing their nuclear entry. Remarkably, FRIL also effectively neutralizes SARS-CoV-2, preventing viral protein production and cytopathic effect in host cells. These findings suggest a potential application of FRIL for the prevention and/or treatment of influenza and COVID-19.


Assuntos
Antivirais/uso terapêutico , Infecções por Coronavirus/tratamento farmacológico , Fabaceae/química , Infecções por Orthomyxoviridae/tratamento farmacológico , Lectinas de Plantas/uso terapêutico , Pneumonia Viral/tratamento farmacológico , Células A549 , Administração Intranasal , Animais , Antivirais/administração & dosagem , Antivirais/farmacologia , Betacoronavirus/efeitos dos fármacos , Embrião de Galinha , Chlorocebus aethiops , Cães , Feminino , Humanos , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Células Madin Darby de Rim Canino , Camundongos , Camundongos Endogâmicos BALB C , Pandemias , Lectinas de Plantas/administração & dosagem , Lectinas de Plantas/farmacologia , Ligação Proteica , Células Vero , Proteínas do Envelope Viral/metabolismo
11.
PLoS One ; 15(7): e0236172, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32726321

RESUMO

There are several broadly neutralizing monoclonal antibodies that neutralize influenza viruses with different mechanisms from traditional polyclonal antibodies induced by vaccination. CT149, which is one of the broadly neutralizing antibodies, was also previously reported to neutralize group 2 and some of group 1 influenza viruses (13 out of 13 tested group 2 viruses and 5 out of 11 group 1 viruses). In this study, we developed another antibody with the aim of compensating partial coverage of CT149 against group 1 influenza viruses. CT120 was screened among different antibody candidates and mixed with CT149. Importantly, although the binding sites of CT120 and CT149 are close to each other, the two antibodies do not interfere. The mixture of CT120 and CT149, which we named as CT-P27, showed broad efficacy by neutralizing 37 viruses from 11 different subtypes, of both group 1 and 2 influenza A viruses. Moreover, CT-P27 showed in vivo therapeutic efficacy, long prophylactic potency, and synergistic effect with oseltamivir in influenza virus-challenged mouse models. Our findings provide a novel therapeutic opportunity for more efficient treatment of influenza.


Assuntos
Anticorpos Monoclonais/farmacocinética , Anticorpos Neutralizantes/farmacologia , Vírus da Influenza A Subtipo H1N1/imunologia , Influenza Humana/imunologia , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Especificidade de Anticorpos/imunologia , Antígenos Virais/imunologia , Hemaglutinação/imunologia , Humanos , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Vírus da Influenza A Subtipo H1N1/patogenicidade , Vírus da Influenza A , Influenza Humana/prevenção & controle , Influenza Humana/virologia , Camundongos , Testes de Neutralização , Vacinação
12.
Front Immunol ; 11: 1102, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32670273

RESUMO

With the sudden outbreak of COVID-19 patient worldwide and associated mortality, it is critical to come up with an effective treatment against SARS-CoV-2. Studies suggest that mortality due to COVID 19 is mainly attributed to the hyper inflammatory response leading to cytokine storm and ARDS in infected patients. Sphingosine-1-phosphate receptor 1 (S1PR1) analogs, AAL-R and RP-002, have earlier provided in-vivo protection from the pathophysiological response during H1N1 influenza infection and improved mortality. Recently, it was shown that the treatment with sphingosine-1-phosphate receptor 1 analog, CYM5442, resulted in the significant dampening of the immune response upon H1N1 challenge in mice and improved survival of H1N1 infected mice in combination with an antiviral drug, oseltamivir. Hence, here we suggest to investigate the possible utility of using S1P analogs to treat COVID-19.


Assuntos
Infecções por Coronavirus/tratamento farmacológico , Síndrome da Liberação de Citocina/prevenção & controle , Indanos/uso terapêutico , Lisofosfolipídeos/agonistas , Oxidiazóis/uso terapêutico , Pneumonia Viral/tratamento farmacológico , Receptores de Esfingosina-1-Fosfato/metabolismo , Esfingosina/análogos & derivados , Animais , Betacoronavirus/efeitos dos fármacos , Betacoronavirus/imunologia , Humanos , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Camundongos , Infecções por Orthomyxoviridae/tratamento farmacológico , Infecções por Orthomyxoviridae/prevenção & controle , Oseltamivir/uso terapêutico , Pandemias , Esfingosina/agonistas
13.
Proc Natl Acad Sci U S A ; 117(31): 18431-18438, 2020 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-32690700

RESUMO

Influenza hemagglutinin (HA) glycoprotein is the primary surface antigen targeted by the host immune response and a focus for development of novel vaccines, broadly neutralizing antibodies (bnAbs), and therapeutics. HA enables viral entry into host cells via receptor binding and membrane fusion and is a validated target for drug discovery. However, to date, only a very few bona fide small molecules have been reported against the HA. To identity new antiviral lead candidates against the highly conserved fusion machinery in the HA stem, we synthesized a fluorescence-polarization probe based on a recently described neutralizing cyclic peptide P7 derived from the complementarity-determining region loops of human bnAbs FI6v3 and CR9114 against the HA stem. We then designed a robust binding assay compatible with high-throughput screening to identify molecules with low micromolar to nanomolar affinity to influenza A group 1 HAs. Our simple, low-cost, and efficient in vitro assay was used to screen H1/Puerto Rico/8/1934 (H1/PR8) HA trimer against ∼72,000 compounds. The crystal structure of H1/PR8 HA in complex with our best hit compound F0045(S) confirmed that it binds to pockets in the HA stem similar to bnAbs FI6v3 and CR9114, cyclic peptide P7, and small-molecule inhibitor JNJ4796. F0045 is enantioselective against a panel of group 1 HAs and F0045(S) exhibits in vitro neutralization activity against multiple H1N1 and H5N1 strains. Our assay, compound characterization, and small-molecule candidate should further stimulate the discovery and development of new compounds with unique chemical scaffolds and enhanced influenza antiviral capabilities.


Assuntos
Antivirais/farmacologia , Avaliação Pré-Clínica de Medicamentos/métodos , Polarização de Fluorescência/métodos , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Virus da Influenza A Subtipo H5N1/efeitos dos fármacos , Influenza Humana/virologia , Bibliotecas de Moléculas Pequenas/farmacologia , Antivirais/química , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Glicoproteínas de Hemaglutininação de Vírus da Influenza/metabolismo , Humanos , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H1N1/metabolismo , Virus da Influenza A Subtipo H5N1/genética , Virus da Influenza A Subtipo H5N1/metabolismo , Bibliotecas de Moléculas Pequenas/química
14.
Cell ; 181(4): 865-876.e12, 2020 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-32353252

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic, caused by the SARS-CoV-2 virus, has highlighted the need for antiviral approaches that can target emerging viruses with no effective vaccines or pharmaceuticals. Here, we demonstrate a CRISPR-Cas13-based strategy, PAC-MAN (prophylactic antiviral CRISPR in human cells), for viral inhibition that can effectively degrade RNA from SARS-CoV-2 sequences and live influenza A virus (IAV) in human lung epithelial cells. We designed and screened CRISPR RNAs (crRNAs) targeting conserved viral regions and identified functional crRNAs targeting SARS-CoV-2. This approach effectively reduced H1N1 IAV load in respiratory epithelial cells. Our bioinformatic analysis showed that a group of only six crRNAs can target more than 90% of all coronaviruses. With the development of a safe and effective system for respiratory tract delivery, PAC-MAN has the potential to become an important pan-coronavirus inhibition strategy.


Assuntos
Antivirais/farmacologia , Betacoronavirus/efeitos dos fármacos , Sistemas CRISPR-Cas , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , RNA Viral/antagonistas & inibidores , Células A549 , Antibioticoprofilaxia/métodos , Sequência de Bases , Betacoronavirus/genética , Betacoronavirus/crescimento & desenvolvimento , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Simulação por Computador , Sequência Conservada , Coronavirus/efeitos dos fármacos , Coronavirus/genética , Coronavirus/crescimento & desenvolvimento , Infecções por Coronavirus/tratamento farmacológico , Células Epiteliais/virologia , Humanos , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H1N1/crescimento & desenvolvimento , Pulmão/patologia , Pulmão/virologia , Proteínas do Nucleocapsídeo/genética , Pandemias , Fosfoproteínas , Filogenia , Pneumonia Viral/tratamento farmacológico , Proteínas não Estruturais Virais/genética
15.
PLoS One ; 15(5): e0233052, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32413095

RESUMO

Severe influenza virus (IV) infections still represent a major challenge to public health. To combat IV infections, vaccines and antiviral compounds are available. However, vaccine efficacies vary with very limited to no protection against newly emerging zoonotic IV introductions. In addition, the development of resistant virus variants against currently available antivirals can be rapidly detected, in consequence demanding the design of novel antiviral strategies. Virus supportive cellular signaling cascades, such as the NF-κB pathway, have been identified to be promising antiviral targets against IV in in vitro and in vivo studies and clinical trials. While administration of NF-κB pathway inhibiting agents, such as LASAG results in decreased IV replication, it remained unclear whether blocking of NF-κB might sensitize cells to secondary bacterial infections, which often come along with viral infections. Thus, we examined IV and Staphylococcus aureus growth during LASAG treatment. Interestingly, our data reveal that the presence of LASAG during superinfection still leads to reduced IV titers. Furthermore, the inhibition of the NF-κB pathway resulted in decreased intracellular Staphylococcus aureus loads within epithelial cells, indicating a dependency on the pathway for bacterial uptake. Unfortunately, so far it is not entirely clear if this phenomenon might be a drawback in bacterial clearance during infection.


Assuntos
Antivirais/efeitos adversos , Aspirina/análogos & derivados , Infecções Bacterianas/etiologia , Glicina/efeitos adversos , Influenza Humana/tratamento farmacológico , Lisina/análogos & derivados , NF-kappa B/antagonistas & inibidores , Células A549 , Aspirina/efeitos adversos , Combinação de Medicamentos , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/microbiologia , Técnicas de Silenciamento de Genes , Humanos , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Vírus da Influenza A Subtipo H1N1/fisiologia , Influenza Humana/complicações , Influenza Humana/virologia , Lisina/efeitos adversos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Infecções Estafilocócicas/etiologia , Superinfecção/etiologia , Fator de Transcrição RelA/antagonistas & inibidores , Fator de Transcrição RelA/genética , Replicação Viral/efeitos dos fármacos
16.
Biochem Pharmacol ; 177: 113982, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32305436

RESUMO

Marine environments are known to be a new source of structurally diverse bioactive molecules. In this paper, we identified a porphyrin derivative of Pyropheophorbide a (PPa) from the mussel Musculus senhousei (M. senhousei) that showed broad anti-influenza A virus activity in vitro against a panel of influenza A viral strains. The analysis of the mechanism of action indicated that PPa functions in the early stage of virus infection by interacting with the lipid bilayer of the virion, resulting in an alteration of membrane-associated functions, thereby blocking the entry of enveloped viruses into host cells. In addition, the anti-influenza A virus activity of PPa was further assessed in mice infected with the influenza A virus. The survival rate and mean survival time of mice were apparently prolonged compared with the control group which was not treated with the drug. Therefore, PPa and its derivatives may represent lead compounds for controlling influenza A virus infection.


Assuntos
Antivirais/farmacologia , Betacoronavirus/efeitos dos fármacos , Bivalves/química , Clorofila/análogos & derivados , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Vírus Sinciciais Respiratórios/efeitos dos fármacos , Vírion/efeitos dos fármacos , Animais , Antivirais/química , Antivirais/isolamento & purificação , Betacoronavirus/crescimento & desenvolvimento , Betacoronavirus/metabolismo , Clorofila/química , Clorofila/isolamento & purificação , Clorofila/farmacologia , Cães , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Vírus da Influenza A Subtipo H1N1/crescimento & desenvolvimento , Vírus da Influenza A Subtipo H1N1/metabolismo , Bicamadas Lipídicas/antagonistas & inibidores , Bicamadas Lipídicas/química , Bicamadas Lipídicas/metabolismo , Células Madin Darby de Rim Canino , Masculino , Camundongos , Infecções por Orthomyxoviridae/tratamento farmacológico , Infecções por Orthomyxoviridae/mortalidade , Infecções por Orthomyxoviridae/patologia , Infecções por Orthomyxoviridae/virologia , Vírus Sinciciais Respiratórios/crescimento & desenvolvimento , Vírus Sinciciais Respiratórios/metabolismo , Alimentos Marinhos , Análise de Sobrevida , Vírion/crescimento & desenvolvimento , Vírion/metabolismo , Internalização do Vírus/efeitos dos fármacos
17.
PLoS Pathog ; 16(4): e1008395, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32294137

RESUMO

Influenza viruses cause seasonal outbreaks and pose a continuous pandemic threat. Although vaccines are available for influenza control, their efficacy varies each season and a vaccine for a novel pandemic virus manufactured using current technology will not be available fast enough to mitigate the effect of the first pandemic wave. Antivirals can be effective against many different influenza viruses but have not thus far been used extensively for outbreak control. Baloxavir, a recently licensed antiviral drug that targets the influenza virus endonuclease, has been shown to reduce virus shedding more effectively than oseltamivir, a widely used neuraminidase inhibitor drug. Thus it is possible that treatment with baloxavir might also interrupt onward virus transmission. To test this, we utilized the ferret model, which is the most commonly used animal model to study influenza virus transmission. We established a subcutaneous baloxavir administration method in ferrets which achieved similar pharmacokinetics to the approved human oral dose. Transmission studies were then conducted in two different locations with different experimental setups to compare the onward transmission of A(H1N1)pdm09 virus from infected ferrets treated with baloxavir, oseltamivir or placebo to naïve sentinel ferrets exposed either indirectly in adjacent cages or directly by co-housing. We found that baloxavir treatment reduced infectious viral shedding in the upper respiratory tract of ferrets compared to placebo, and reduced the frequency of transmission amongst sentinels in both experimental setups, even when treatment was delayed until 2 days post-infection. In contrast, oseltamivir treatment did not substantially affect viral shedding or transmission compared to placebo. We did not detect the emergence of baloxavir-resistant variants in treated animals or in untreated sentinels. Our results support the concept that antivirals which decrease viral shedding could also reduce influenza transmission in the community.


Assuntos
Antivirais/farmacologia , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Neuraminidase/antagonistas & inibidores , Infecções por Orthomyxoviridae/tratamento farmacológico , Oxazinas/farmacologia , Piridinas/farmacologia , Tiepinas/farmacologia , Triazinas/farmacologia , Replicação Viral/efeitos dos fármacos , Eliminação de Partículas Virais/efeitos dos fármacos , Animais , Dibenzotiepinas , Feminino , Furões , Morfolinas , Infecções por Orthomyxoviridae/transmissão , Infecções por Orthomyxoviridae/virologia , Piridonas
18.
J Infect Chemother ; 26(8): 775-779, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32249161

RESUMO

To assess the extent of susceptibility to the four most commonly used neuraminidase inhibitors (NAIs) of the epidemic viruses in the 2018-19 Japanese influenza season, we measured the 50% inhibitory concentration (IC50) of four NAIs, oseltamivir, zanamivir, peramivir, and laninamivir, for influenza virus isolates from patients and compared them with the results from the 2010-11 to 2017-18 seasons. Viral isolation was done with specimens obtained prior to and after treatment, and the type/subtype was determined by RT-PCR using type- and subtype-specific primers. The IC50 was determined by a neuraminidase inhibition assay using a fluorescent substrate. Virus isolates, 51 A(H1N1)pdm09, 125 A(H3N2), and one B, were measured in the 2018-19 season and the geometric mean IC50s of the four NAIs were quite comparable to the previous eight studied seasons. No A(H1N1)pdm09 with highly reduced sensitivity for oseltamivir was found in the 2018-19 season prior to drug administration, although such A(H1N1)pdm09 were found in two, two, and two samples in the 2010-11, 2013-14, and 2015-16 seasons, respectively. No isolates with highly reduced sensitivity to the four NAIs were found for A(H3N2) or B through the 2010-11 to 2018-19 seasons. Among 18 samples with A(H1N1)pdm09 virus isolated after NAI administration, highly reduced sensitivity to oseltamivir and peramivir was detected from one of the five patients treated with oseltamivir. These results suggest that the sensitivity to the four commonly used NAIs has been maintained, although viruses with highly reduced sensitivity to oseltamivir and peramivir have emerged in some adult patients treated with oseltamivir.


Assuntos
Antivirais/farmacologia , Inibidores Enzimáticos/farmacologia , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Vírus da Influenza A Subtipo H3N2/efeitos dos fármacos , Vírus da Influenza B/efeitos dos fármacos , Influenza Humana/virologia , Neuraminidase/antagonistas & inibidores , Ácidos Carbocíclicos , Adolescente , Adulto , Criança , Ciclopentanos/farmacologia , Farmacorresistência Viral , Feminino , Guanidinas/farmacologia , Humanos , Influenza Humana/tratamento farmacológico , Concentração Inibidora 50 , Japão , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Oseltamivir/farmacologia , Piranos , Estações do Ano , Ácidos Siálicos , Adulto Jovem , Zanamivir/análogos & derivados , Zanamivir/farmacologia
19.
Proc Natl Acad Sci U S A ; 117(15): 8593-8601, 2020 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-32217734

RESUMO

Baloxavir marboxil (BXM) was approved in 2018 for treating influenza A and B virus infections. It is a first-in-class inhibitor targeting the endonuclease activity of the virus polymerase acidic (PA) protein. Clinical trial data revealed that PA amino acid substitutions at residue 38 (I38T/F/M) reduced BXM potency and caused virus rebound in treated patients, although the fitness characteristics of the mutant viruses were not fully defined. To determine the fitness impact of the I38T/F/M substitutions, we generated recombinant A/California/04/2009 (H1N1)pdm09, A/Texas/71/2017 (H3N2), and B/Brisbane/60/2008 viruses with I38T/F/M and examined drug susceptibility in vitro, enzymatic properties, replication efficiency, and transmissibility in ferrets. Influenza viruses with I38T/F/M substitutions exhibited reduced baloxavir susceptibility, with 38T causing the greatest reduction. The I38T/F/M substitutions impaired PA endonuclease activity as compared to that of wild-type (I38-WT) PA. However, only 38T/F A(H3N2) substitutions had a negative effect on polymerase complex activity. The 38T/F substitutions decreased replication in cells among all viruses, whereas 38M had minimal impact. Despite variable fitness consequences in vitro, all 38T/M viruses disseminated to naive ferrets by contact and airborne transmission, while 38F-containing A(H3N2) and B viruses failed to transmit via the airborne route. Reversion of 38T/F/M to I38-WT was rare among influenza A viruses in this study, suggesting stable retention of 38T/F/M genotypes during these transmission events. BXM reduced susceptibility-associated mutations had variable effects on in vitro fitness of influenza A and B viruses, but the ability of these viruses to transmit in vivo indicates a risk of their spreading from BXM-treated individuals.


Assuntos
Farmacorresistência Viral , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Vírus da Influenza A Subtipo H3N2/efeitos dos fármacos , Vírus da Influenza B/efeitos dos fármacos , Infecções por Orthomyxoviridae/transmissão , Oxazinas/farmacologia , Piridinas/farmacologia , Tiepinas/farmacologia , Triazinas/farmacologia , Replicação Viral , Substituição de Aminoácidos , Animais , Antivirais/farmacologia , Dibenzotiepinas , Furões , Masculino , Testes de Sensibilidade Microbiana , Morfolinas , Infecções por Orthomyxoviridae/tratamento farmacológico , Infecções por Orthomyxoviridae/veterinária , Infecções por Orthomyxoviridae/virologia , Piridonas , Proteínas Virais/genética , Proteínas Virais/metabolismo
20.
J Nanobiotechnology ; 18(1): 54, 2020 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-32209114

RESUMO

BACKGROUND: Influenza viruses (IVs) have become increasingly resistant to antiviral drugs that target neuraminidase and matrix protein 2 due to gene mutations that alter their drug-binding target protein regions. Consequently, almost all recent IV pandemics have exhibited resistance to commercial antiviral vaccines. To overcome this challenge, an antiviral target is needed that is effective regardless of genetic mutations. MAIN BODY: In particular, hemagglutinin (HA), a highly conserved surface protein across many IV strains, could be an effective antiviral target as it mediates binding of IVs with host cell receptors, which is crucial for membrane fusion. HA has 6 disulfide bonds that can easily bind with the surfaces of gold nanoparticles. Herein, we fabricated porous gold nanoparticles (PoGNPs) via a surfactant-free emulsion method that exhibited strong affinity for disulfide bonds due to gold-thiol interactions, and provided extensive surface area for these interactions. A remarkable decrease in viral infectivity was demonstrated by increased cell viability results after exposing MDCK cells to various IV strains (H1N1, H3N2, and H9N2) treated with PoGNP. Most of all, the viability of MDCK cells infected with all IV strains increased to 96.8% after PoGNP treatment of the viruses compared to 33.9% cell viability with non-treated viruses. Intracellular viral RNA quantification by real-time RT-PCR also confirmed that PoGNP successfully inhibited viral membrane fusion by blocking the viral entry process through conformational deformation of HA. CONCLUSION: We believe that the technique described herein can be further developed for PoGNP-utilized antiviral protection as well as metal nanoparticle-based therapy to treat viral infection. Additionally, facile detection of IAV can be achieved by developing PoGNP as a multiplatform for detection of the virus.


Assuntos
Antivirais/farmacologia , Ouro/farmacologia , Vírus da Influenza A/efeitos dos fármacos , Nanopartículas Metálicas/química , Animais , Cães , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H3N2/efeitos dos fármacos , Vírus da Influenza A Subtipo H3N2/genética , Vírus da Influenza A Subtipo H9N2/efeitos dos fármacos , Vírus da Influenza A Subtipo H9N2/genética , Vírus da Influenza A/genética , Células Madin Darby de Rim Canino , Fusão de Membrana , Porosidade , RNA Viral/análise , RNA Viral/genética , Internalização do Vírus
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