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1.
Int J Biol Macromol ; 275(Pt 1): 133564, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38955298

RESUMO

Influenza viruses contribute significantly to the global health burden, necessitating the development of strategies against transmission as well as effective antiviral treatments. The present study reports a biomimetic strategy inspired by the natural antiviral properties of mucins. A bovine serum albumin (BSA) conjugate decorated with the multivalent neuraminidase inhibitor Zanamivir (ZA-BSA) was synthesized using copper-free click chemistry. This synthetic pseudo-mucin exhibited potent neuraminidase inhibitory activity against several influenza strains. Virus capture and growth inhibition assays demonstrated its effective absorption of virion particles and ability to prevent viral infection in nanomolar concentrations. Investigation of the underlying antiviral mechanism of ZA-BSA revealed a dual mode of action, involving disruption of the initial stages of host-cell binding and fusion by inducing viral aggregation, followed by blocking the release of newly assembled virions by targeting neuraminidase activity. Notably, the conjugate also exhibited potent inhibitory activity against Oseltamivir-resistant neuraminidase variant comparable to the monomeric Zanamivir. These findings highlight the application of multivalent drug presentation on protein scaffold to mimic mucin adsorption of viruses, together with counteracting drug resistance. This innovative approach has potential for the creation of antiviral agents against influenza and other viral infections.


Assuntos
Antivirais , Mucinas , Neuraminidase , Vírion , Zanamivir , Neuraminidase/antagonistas & inibidores , Neuraminidase/metabolismo , Zanamivir/farmacologia , Zanamivir/química , Antivirais/farmacologia , Antivirais/química , Mucinas/metabolismo , Mucinas/química , Humanos , Vírion/efeitos dos fármacos , Animais , Soroalbumina Bovina/química , Cães , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/química , Células Madin Darby de Rim Canino , Orthomyxoviridae/efeitos dos fármacos , Orthomyxoviridae/enzimologia
2.
Antiviral Res ; 229: 105959, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38986873

RESUMO

Avian influenza outbreaks, including ones caused by highly pathogenic A(H5N1) clade 2.3.4.4b viruses, have devastated animal populations and remain a threat to humans. Risk elements assessed for emerging influenza viruses include their susceptibility to approved antivirals. Here, we screened >20,000 neuraminidase (NA) or polymerase acidic (PA) protein sequences of potentially pandemic A(H5Nx), A(H7Nx), and A(H9N2) viruses that circulated globally in 2010-2023. The frequencies of NA or PA substitutions associated with reduced inhibition (RI) or highly reduced inhibition (HRI) by NA inhibitors (NAIs) (oseltamivir, zanamivir) or a cap-dependent endonuclease inhibitor (baloxavir) were low: 0.60% (137/22,713) and 0.62% (126/20,347), respectively. All tested subtypes were susceptible to NAIs and baloxavir at sub-nanomolar concentrations. A(H9N2) viruses were the most susceptible to oseltamivir, with IC50s 3- to 4-fold lower than for other subtypes (median IC50: 0.18 nM; n = 22). NA-I222M conferred RI of A(H5N1) viruses by oseltamivir (with a 26-fold IC50 increase), but NA-S246N did not reduce inhibition. PA-E23G, PA-K34R, PA-I38M/T, and the previously unreported PA-A36T caused RI by baloxavir in all subtypes tested. Avian A(H9N2) viruses endemic in Egyptian poultry predominantly acquired PA-I38V, which causes only a <3-fold decrease in the baloxavir EC50 and fails to meet the RI criteria. PA-E199A/D in A(H7Nx) and A(H9N2) viruses caused a 2- to 4-fold decrease in EC50 (close to the borderline for RI) and should be closely monitored. Our data indicate antiviral susceptibility is high among avian influenza A viruses with pandemic potential and present novel markers of resistance to existing antiviral interventions.


Assuntos
Antivirais , Aves , Dibenzotiepinas , Farmacorresistência Viral , Inibidores Enzimáticos , Genótipo , Vírus da Influenza A , Influenza Aviária , Neuraminidase , Oseltamivir , Piridonas , Triazinas , Neuraminidase/antagonistas & inibidores , Neuraminidase/genética , Antivirais/farmacologia , Influenza Aviária/virologia , Animais , Inibidores Enzimáticos/farmacologia , Dibenzotiepinas/farmacologia , Farmacorresistência Viral/genética , Piridonas/farmacologia , Vírus da Influenza A/efeitos dos fármacos , Vírus da Influenza A/genética , Vírus da Influenza A/enzimologia , Triazinas/farmacologia , Oseltamivir/farmacologia , Aves/virologia , Morfolinas/farmacologia , Endonucleases/antagonistas & inibidores , Endonucleases/genética , Endonucleases/metabolismo , Vírus da Influenza A Subtipo H9N2/efeitos dos fármacos , Vírus da Influenza A Subtipo H9N2/genética , Proteínas Virais/genética , Proteínas Virais/antagonistas & inibidores , Virus da Influenza A Subtipo H5N1/efeitos dos fármacos , Virus da Influenza A Subtipo H5N1/genética , Virus da Influenza A Subtipo H5N1/enzimologia , Zanamivir/farmacologia , Fenótipo , Humanos , Concentração Inibidora 50
3.
Antiviral Res ; 228: 105938, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38897317

RESUMO

We compared the duration of fever in children infected with A(H1N1)pdm09, A(H3N2), or influenza B viruses following treatment with baloxavir marboxil (baloxavir) or neuraminidase inhibitors (NAIs) (oseltamivir, zanamivir, or laninamivir). This observational study was conducted at 10 outpatient clinics across 9 prefectures in Japan during the 2012-2013 and 2019-2020 influenza seasons. Patients with influenza rapid antigen test positive were treated with one of four anti-influenza drugs. The type/subtype of influenza viruses were identified from MDCK or MDCK SIAT1 cell-grown samples using two-step real-time PCR. Daily self-reported body temperature after treatment were used to evaluate the duration of fever by treatment group and various underlying factors. Among 1742 patients <19 years old analyzed, 452 (26.0%) were A(H1N1)pdm09, 827 (48.0%) A(H3N2), and 463 (26.0%) influenza B virus infections. Among fours treatment groups, baloxavir showed a shorter median duration of fever compared to oseltamivir in univariate analysis for A(H1N1)pdm09 virus infections (baloxavir, 22.0 h versus oseltamivir, 26.7 h, P < 0.05; laninamivir, 25.5 h, and zanamivir, 25.0 h). However, this difference was not significant in multivariable analyses. For A(H3N2) virus infections, there were no statistically significant differences observed (20.3, 21.0, 22.0, and 19.0 h) uni- and multivariable analyses. For influenza B, baloxavir shortened the fever duration by approximately 15 h than NAIs (20.3, 35.0, 34.3, and 34.1 h), as supported by uni- and multivariable analyses. Baloxavir seems to have comparable clinical effectiveness with NAIs on influenza A but can be more effective for treating pediatric influenza B virus infections than NAIs.


Assuntos
Antivirais , Dibenzotiepinas , Febre , Guanidinas , Vírus da Influenza A Subtipo H1N1 , Vírus da Influenza A Subtipo H3N2 , Vírus da Influenza B , Influenza Humana , Morfolinas , Oseltamivir , Piranos , Piridonas , Ácidos Siálicos , Triazinas , Zanamivir , Humanos , Influenza Humana/tratamento farmacológico , Influenza Humana/virologia , Antivirais/uso terapêutico , Antivirais/farmacologia , Vírus da Influenza B/efeitos dos fármacos , Vírus da Influenza B/genética , Criança , Zanamivir/uso terapêutico , Zanamivir/análogos & derivados , Zanamivir/farmacologia , Triazinas/uso terapêutico , Triazinas/farmacologia , Guanidinas/uso terapêutico , Vírus da Influenza A Subtipo H3N2/efeitos dos fármacos , Vírus da Influenza A Subtipo H3N2/genética , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Piridonas/uso terapêutico , Dibenzotiepinas/uso terapêutico , Japão , Feminino , Masculino , Pré-Escolar , Oseltamivir/uso terapêutico , Febre/tratamento farmacológico , Febre/virologia , Adolescente , Morfolinas/uso terapêutico , Lactente , Estações do Ano , Tiepinas/uso terapêutico , Tiepinas/farmacologia , Oxazinas/uso terapêutico , Fatores de Tempo , Benzoxazinas/uso terapêutico
4.
Antiviral Res ; 227: 105918, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38795911

RESUMO

The most widely used class of antivirals available for Influenza treatment are the neuraminidase inhibitors (NAI) Oseltamivir and Zanamivir. However, amino acid (AA) substitutions in the neuraminidase may cause reduced inhibition or high antiviral resistance. In Mexico, the current state of knowledge about NAI susceptibility is scarce, in this study we report the results of 14 years of Influenza surveillance by phenotypic and genotypic methods. A total of 255 isolates were assessed with the NAI assay, including Influenza A(H1N1)pdm09, A(H3N2) and Influenza B (IBV). Furthermore, 827 sequences contained in the GISAID platform were analyzed in search of relevant mutations.Overall, five isolates showed highly reduced inhibition or reduced inhibition to Oseltamivir, and two showed reduced inhibition to Zanamivir in the NAI assays. Additionally, five A(H1N1)pdm09 sequences from the GISAID possessed AA substitutions associated to reduced inhibition to Oseltamivir and none to Zanamivir. Oseltamivir resistant A(H1N1)pdm09 harbored the H275Y mutation. No genetic mutations were identified in Influenza A(H3N2) and IBV. Overall, these results show that in Mexico the rate of NAI resistance is low (0.6%), but it is essential to continue the Influenza surveillance in order to understand the drug susceptibility of circulating strains.


Assuntos
Antivirais , Farmacorresistência Viral , Vírus da Influenza B , Influenza Humana , Neuraminidase , Oseltamivir , Zanamivir , Farmacorresistência Viral/genética , Antivirais/farmacologia , México/epidemiologia , Humanos , Vírus da Influenza B/efeitos dos fármacos , Vírus da Influenza B/genética , Influenza Humana/virologia , Influenza Humana/tratamento farmacológico , Influenza Humana/epidemiologia , Oseltamivir/farmacologia , Zanamivir/farmacologia , Neuraminidase/genética , Neuraminidase/antagonistas & inibidores , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Mutação , Vírus da Influenza A Subtipo H3N2/efeitos dos fármacos , Vírus da Influenza A Subtipo H3N2/genética , Adulto , Vírus da Influenza A/efeitos dos fármacos , Vírus da Influenza A/genética , Adolescente , Criança , Substituição de Aminoácidos , Adulto Jovem , Pessoa de Meia-Idade , Feminino , Pré-Escolar , Genótipo , Masculino , Idoso , Testes de Sensibilidade Microbiana , Proteínas Virais/genética
5.
EMBO Mol Med ; 16(6): 1228-1253, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38789599

RESUMO

In the injured brain, new neurons produced from endogenous neural stem cells form chains and migrate to injured areas and contribute to the regeneration of lost neurons. However, this endogenous regenerative capacity of the brain has not yet been leveraged for the treatment of brain injury. Here, we show that in healthy brain chains of migrating new neurons maintain unexpectedly large non-adherent areas between neighboring cells, allowing for efficient migration. In instances of brain injury, neuraminidase reduces polysialic acid levels, which negatively regulates adhesion, leading to increased cell-cell adhesion and reduced migration efficiency. The administration of zanamivir, a neuraminidase inhibitor used for influenza treatment, promotes neuronal migration toward damaged regions, fosters neuronal regeneration, and facilitates functional recovery. Together, these findings shed light on a new mechanism governing efficient neuronal migration in the adult brain under physiological conditions, pinpoint the disruption of this mechanism during brain injury, and propose a promising therapeutic avenue for brain injury through drug repositioning.


Assuntos
Encéfalo , Movimento Celular , Neuraminidase , Neurônios , Neuraminidase/metabolismo , Neuraminidase/antagonistas & inibidores , Movimento Celular/efeitos dos fármacos , Animais , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Camundongos , Zanamivir/farmacologia , Inibidores Enzimáticos/farmacologia , Ácidos Siálicos/metabolismo , Lesões Encefálicas/tratamento farmacológico , Lesões Encefálicas/metabolismo , Recuperação de Função Fisiológica/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Adesão Celular/efeitos dos fármacos , Humanos , Masculino
6.
mBio ; 15(5): e0017524, 2024 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-38551343

RESUMO

Influenza viruses (IVs) threaten global human health due to the high morbidity, infection, and mortality rates. Currently, the influenza drugs recommended by the Food and Drug Administration are oseltamivir, zanamivir, peramivir, and baloxavir marboxil. These recommended antivirals are currently effective for major subtypes of IVs as the compounds target conserved domains in neuraminidase or polymerase acidic (PA) protein. However, this trend may gradually change due to the selection of antiviral drugs and the natural evolution of IVs. Therefore, there is an urgent need to develop drugs related to the treatment of influenza to deal with the next pandemic. Here, we summarized the cutting-edge research in mechanism of action, inhibitory activity, and clinical efficacy of drugs that have been approved and drugs that are still in clinical trials for influenza treatment. We hope this review will provide up-to-date and comprehensive information on influenza antivirals and generate hypotheses for screens and development of new broad-spectrum influenza drugs in the near future.


Assuntos
Antivirais , Ensaios Clínicos como Assunto , Desenvolvimento de Medicamentos , Influenza Humana , Humanos , Antivirais/farmacologia , Antivirais/uso terapêutico , Dibenzotiepinas , Influenza Humana/tratamento farmacológico , Influenza Humana/virologia , Morfolinas , Orthomyxoviridae/efeitos dos fármacos , Piridonas , Triazinas , Zanamivir/farmacologia , Zanamivir/uso terapêutico
7.
J Infect Chemother ; 30(3): 266-270, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37832825

RESUMO

To assess the extent of susceptibility to the four neuraminidase inhibitors (NAIs) approved in Japan of the epidemic viruses in the 2022-23 influenza season in Japan, we measured the 50 % inhibitory concentration (IC50) of oseltamivir, zanamivir, peramivir, and laninamivir in influenza virus isolates from patients. 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, one A(H1N1)pdm09 and 74 A(H3N2), were measured in the 2022-23 season. The geometric mean IC50s of the 74 A(H3N2) isolated prior to treatment were 0.78 nM, 0.66 nM, 2.08 nM, and 2.85 nM for oseltamivir, peramivir, zanamivir, and laninamivir, respectively, comparable to those of the previous ten studied seasons. No A(H3N2) with highly reduced sensitivity to any of the NAIs was found in the 2022-23 season prior to or after drug administration. These results indicate that the sensitivity to these four commonly used NAIs has been maintained, at least for A(H3N2), in the 2022-23 influenza season in Japan, after the 2020-21 and 2021-22 seasons when the prevalence of influenza was extremely low.


Assuntos
Ácidos Carbocíclicos , Guanidinas , Vírus da Influenza A Subtipo H1N1 , Influenza Humana , Piranos , Ácidos Siálicos , Humanos , Zanamivir/farmacologia , Zanamivir/uso terapêutico , Oseltamivir/farmacologia , Oseltamivir/uso terapêutico , Neuraminidase , Estações do Ano , Japão/epidemiologia , Vírus da Influenza A Subtipo H3N2 , Antivirais/farmacologia , Antivirais/uso terapêutico , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico
8.
J Virol Methods ; 323: 114838, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37914041

RESUMO

In influenza A virus-infected cells, newly synthesized viral neuraminidases (NAs) transiently localize at the host cell Golgi due to glycosylation, before their expression on the cell surface. It remains unproven whether Golgi-localized intracellular NAs exhibit sialidase activity. We have developed a sialidase imaging probe, [2-(benzothiazol-2-yl)-5-(non-1-yn-1-yl) phenyl]-α-D-N-acetylneuraminic acid (BTP9-Neu5Ac). This probe is designed to be cleaved by sialidase activity, resulting in the release of a hydrophobic fluorescent compound, 2-(benzothiazol-2-yl)-5-(non-1-yn-1-yl) phenol (BTP9). BTP9-Neu5Ac makes the location of sialidase activity visually detectable by the BTP9 fluorescence that results from the action of sialidase activity. In this study, we established a protocol to visualize the sialidase activity of intracellular NA at the Golgi of influenza A virus-infected cells using BTP9-Neu5Ac. Furthermore, we employed this fluorescence imaging protocol to elucidate the intracellular inhibition of laninamivir octanoate, an anti-influenza drug. At approximately 7 h after infection, newly synthesized viral NAs localized at the Golgi. Using our developed protocol, we successfully histochemically stained the sialidase activity of intracellular viral NAs localized at the Golgi. Importantly, we observed that laninamivir octanoate effectively inhibited the intracellular viral NA, in contrast to drugs like zanamivir or laninamivir. Our study establishes a visualization protocol for intracellular viral NA sialidase activity and visualizes the inhibitory effect of laninamivir octanoate on Golgi-localized intracellular viral NA in infected cells.


Assuntos
Antivirais , Inibidores Enzimáticos , Vírus da Influenza A , Neuraminidase , Proteínas Virais , Humanos , Antivirais/farmacologia , Vírus da Influenza A/efeitos dos fármacos , Vírus da Influenza A/enzimologia , Neuraminidase/análise , Neuraminidase/antagonistas & inibidores , Imagem Óptica/métodos , Zanamivir/farmacologia , Proteínas Virais/análise , Proteínas Virais/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia
9.
Artigo em Inglês | MEDLINE | ID: mdl-37817300

RESUMO

As part of its role in the World Health Organization's (WHO) Global Influenza Surveillance and Response System (GISRS), the WHO Collaborating Centre for Reference and Research on Influenza in Melbourne received a record total of 12,073 human influenza positive samples during 2022. Viruses were analysed for their antigenic, genetic and antiviral susceptibility properties. Selected viruses were propagated in qualified cells or embryonated hen's eggs for potential use in seasonal influenza virus vaccines. In 2022, influenza A(H3N2) viruses predominated over influenza A(H1N1)pdm09 and B viruses, accounting for 77% of all viruses analysed. The majority of A(H1N1)pdm09, A(H3N2) and influenza B viruses analysed at the Centre were found to be antigenically and genetically similar to the respective WHO recommended vaccine strains for the southern hemisphere in 2022. Of 3,372 samples tested for susceptibility to the neuraminidase inhibitors oseltamivir and zanamivir, two A(H1N1)pdm09 viruses showed highly reduced inhibition against oseltamivir.


Assuntos
Vírus da Influenza A , Vacinas contra Influenza , Influenza Humana , Animais , Feminino , Humanos , Austrália/epidemiologia , Galinhas , Farmacorresistência Viral/genética , Farmacorresistência Viral/imunologia , Vírus da Influenza A/efeitos dos fármacos , Vírus da Influenza A/genética , Vírus da Influenza A/imunologia , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H3N2/genética , Vacinas contra Influenza/genética , Vacinas contra Influenza/imunologia , Vacinas contra Influenza/uso terapêutico , Influenza Humana/epidemiologia , Influenza Humana/genética , Influenza Humana/imunologia , Influenza Humana/prevenção & controle , Oseltamivir/farmacologia , Organização Mundial da Saúde , Zanamivir/farmacologia , Antivirais/farmacologia
10.
Am J Physiol Heart Circ Physiol ; 325(6): H1337-H1353, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37801046

RESUMO

Neuraminidases cleave sialic acids from glycocalyx structures and plasma neuraminidase activity is elevated in type 2 diabetes (T2D). Therefore, we hypothesize circulating neuraminidase degrades the endothelial glycocalyx and diminishes flow-mediated dilation (FMD), whereas its inhibition restores shear mechanosensation and endothelial function in T2D settings. We found that compared with controls, subjects with T2D have higher plasma neuraminidase activity, reduced plasma nitrite concentrations, and diminished FMD. Ex vivo and in vivo neuraminidase exposure diminished FMD and reduced endothelial glycocalyx presence in mouse arteries. In cultured endothelial cells, neuraminidase reduced glycocalyx coverage. Inhalation of the neuraminidase inhibitor, zanamivir, reduced plasma neuraminidase activity, enhanced endothelial glycocalyx length, and improved FMD in diabetic mice. In humans, a single-arm trial (NCT04867707) of zanamivir inhalation did not reduce plasma neuraminidase activity, improved glycocalyx length, or enhanced FMD. Although zanamivir plasma concentrations in mice reached 225.8 ± 22.0 ng/mL, in humans were only 40.0 ± 7.2 ng/mL. These results highlight the potential of neuraminidase inhibition for ameliorating endothelial dysfunction in T2D and suggest the current Food and Drug Administration-approved inhaled dosage of zanamivir is insufficient to achieve desired outcomes in humans.NEW & NOTEWORTHY This work identifies neuraminidase as a key mediator of endothelial dysfunction in type 2 diabetes that may serve as a biomarker for impaired endothelial function and predictive of development and progression of cardiovascular pathologies associated with type 2 diabetes (T2D). Data show that intervention with the neuraminidase inhibitor zanamivir at effective plasma concentrations may represent a novel pharmacological strategy for restoring the glycocalyx and ameliorating endothelial dysfunction.


Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Doenças Vasculares , Camundongos , Humanos , Animais , Zanamivir/farmacologia , Neuraminidase/química , Neuraminidase/farmacologia , Células Endoteliais , Diabetes Mellitus Tipo 2/tratamento farmacológico , Antivirais/farmacologia , Inibidores Enzimáticos/farmacologia
11.
Antiviral Res ; 217: 105701, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37567255

RESUMO

Neuraminidase inhibitors (NAIs) are recommended for influenza treatment and prevention worldwide. The most widely prescribed NAI is oral oseltamivir, while inhaled zanamivir is less commonly used. Using phenotypic neuraminidase (NA) enzymatic assays and molecular modeling approaches, we examined the ability of the investigational orally-dosed NAI AV5080 to inhibit viruses of the influenza A(H1N1)pdm09, A(H3N2), A(H5N1), and A(H7N9) subtypes and the influenza B/Victoria- and B/Yamagata-lineages containing NA substitutions conferring oseltamivir or zanamivir resistance including: NA-R292K, NA-E119G/V, NA-H274Y, NA-I122L/N, and NA-R150K. Broadly, AV5080 showed enhanced in vitro efficacy when compared with oseltamivir and/or zanamivir. Reduced AV5080 inhibition was determined for influenza A viruses with NA-E119G and NA-R292K, and for B/Victoria-lineage viruses with NA-I122N/L and B/Yamagata-lineage virus with NA-R150K. Molecular modeling suggested loss of the short hydrogen bond to the carboxyl group of AV5080 affected inhibition of NA-R292K viruses, whereas loss of the salt bridge with the guanidine group of AV5080 affected inhibition of NA-E119G. The resistance profiles and predicted binding modes of AV5080 and zanamivir are most similar, but dissimilar to those of oseltamivir, in part because of a guanidine moiety compensatory binding effect. Overall, our data suggests that AV5080 is a promising orally-dosed NAI that exhibited similar or superior in vitro efficacy against viruses with reduced or highly reduced inhibition phenotypes with respect to currently approved NAIs.


Assuntos
Herpesvirus Cercopitecino 1 , Vírus da Influenza A Subtipo H1N1 , Virus da Influenza A Subtipo H5N1 , Subtipo H7N9 do Vírus da Influenza A , Influenza Humana , Humanos , Antivirais/farmacologia , Farmacorresistência Viral/genética , Inibidores Enzimáticos/farmacologia , Guanidina/metabolismo , Guanidinas/metabolismo , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Vírus da Influenza A Subtipo H3N2 , Influenza Humana/virologia , Neuraminidase/genética , Oseltamivir/farmacologia , Zanamivir/farmacologia
12.
Sci Immunol ; 8(84): eadg9459, 2023 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-37352373

RESUMO

The immune system eliminates pathogen intruders such as viruses and bacteria. To recruit immune effectors to virus-infected cells, we conjugated a small molecule, the influenza neuraminidase inhibitor zanamivir, to a nanobody that recognizes the kappa light chains of mouse immunoglobulins. This adduct was designed to achieve half-life extension of zanamivir through complex formation with the much-larger immunoglobulins in the circulation. The zanamivir moiety targets the adduct to virus-infected cells, whereas the anti-kappa component simultaneously delivers polyclonal immunoglobulins of indeterminate specificity and all isotypes. Activation of antibody-dependent cell-mediated cytotoxicity and complement-dependent cytotoxicity promoted elimination of influenza neuraminidase-positive cells. A single dose of the conjugate protected mice against influenza A or B viruses and was effective even when given several days after infection with a lethal dose of virus. In the absence of circulating immunoglobulins, we observed no in vivo protection from the adduct. The type of conjugates described here may thus find application for both anti-influenza prophylaxis and therapy.


Assuntos
Influenza Humana , Zanamivir , Camundongos , Animais , Humanos , Zanamivir/farmacologia , Zanamivir/uso terapêutico , Oseltamivir/farmacologia , Oseltamivir/uso terapêutico , Cadeias Leves de Imunoglobulina/uso terapêutico , Neuraminidase/uso terapêutico , Influenza Humana/prevenção & controle , Camundongos Endogâmicos BALB C
13.
Viruses ; 15(5)2023 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-37243142

RESUMO

In this study, we describe the input data and processing steps to find antiviral lead compounds by a virtual screen. Two-dimensional and three-dimensional filters were designed based on the X-ray crystallographic structures of viral neuraminidase co-crystallized with substrate sialic acid, substrate-like DANA, and four inhibitors (oseltamivir, zanamivir, laninamivir, and peramivir). As a result, ligand-receptor interactions were modeled, and those necessary for binding were utilized as screen filters. Prospective virtual screening (VS) was carried out in a virtual chemical library of over half a million small organic substances. Orderly filtered moieties were investigated based on 2D- and 3D-predicted binding fingerprints disregarding the "rule-of-five" for drug likeness, and followed by docking and ADMET profiling. Two-dimensional and three-dimensional screening were supervised after enriching the dataset with known reference drugs and decoys. All 2D, 3D, and 4D procedures were calibrated before execution, and were then validated. Presently, two top-ranked substances underwent successful patent filing. In addition, the study demonstrates how to work around reported VS pitfalls in detail.


Assuntos
Vírus da Influenza A , Influenza Humana , Humanos , Inibidores Enzimáticos/farmacologia , Estudos Prospectivos , Zanamivir/farmacologia , Antivirais/uso terapêutico , Vírus da Influenza A/metabolismo , Neuraminidase/metabolismo , Influenza Humana/tratamento farmacológico , Influenza Humana/prevenção & controle
14.
Nano Lett ; 23(11): 4844-4853, 2023 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-37220024

RESUMO

Here, we demonstrate the concerted inhibition of different influenza A virus (IAV) strains using a low-molecular-weight dual-action linear polymer. The 6'-sialyllactose and zanamivir conjugates of linear polyglycerol are optimized for simultaneous targeting of hemagglutinin and neuraminidase on the IAV surface. Independent of IAV subtypes, hemagglutination inhibition data suggest better adsorption of the heteromultivalent polymer than homomultivalent analogs onto the virus surface. Cryo-TEM images imply heteromultivalent compound-mediated virus aggregation. The optimized polymeric nanomaterial inhibits >99.9% propagation of various IAV strains 24 h postinfection in vitro at low nM concentrations and is up to 10000× more effective than the commercial zanamivir drug. In a human lung ex vivo multicyclic infection setup, the heteromultivalent polymer outperforms the commercial drug zanamivir and homomultivalent analogs or their physical mixtures. This study authenticates the translational potential of the dual-action targeting approach using small polymers for broad and high antiviral efficacy.


Assuntos
Alphainfluenzavirus , Glicosilação , Polímeros/química , Polímeros/farmacologia , Alphainfluenzavirus/efeitos dos fármacos , Influenza Humana/tratamento farmacológico , Antivirais/química , Antivirais/farmacologia , Humanos , Zanamivir/química , Zanamivir/farmacologia
15.
Eur J Med Chem ; 255: 115410, 2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37120995

RESUMO

The influenza virus remains a major health concern for mankind because it tends to mutate frequently and cause high morbidity. Influenza prevention and treatment are greatly aided by the use of antivirals. One such class of antivirals is neuraminidase inhibitors (NAIs), effective against influenza viruses. A neuraminidase on the virus's surface serves a vital function in viral propogation by assisting in the release of viruses from infected host cells. Neuraminidase inhibitors are the backbone in stoping such virus propagation thus helps in the treatment of influenza viruses infections. Two NAI medicines are licensed globally: Oseltamivir (Tamiflu™) and Zanamivir (Relanza™). There are two molecules that have acquired Japanese approval recently: Peramivir and Laninamivir, whereas Laninamivir octanoate is in Phase III clinical trials. The need for novel NAIs is due to frequent mutations in viruses and the rise in resistance against existing medication. The NA inhibitors (NAIs) are designed to have (oxa)cyclohexene scaffolds (a sugar scaffold) to mimic the oxonium transition state in the enzymatic cleavage of sialic acid. This review discusses in details and comprises all such conformationally locked (oxa)cyclohexene scaffolds and their analogues which have been recently designed and synthesized as potential neuraminidase inhibitors, thus as antiviral molecules. The structure-activity relationship of such diverese molecules has also been discussed in this review.


Assuntos
Influenza Humana , Orthomyxoviridae , Humanos , Neuraminidase , Antivirais/farmacologia , Antivirais/uso terapêutico , Zanamivir/farmacologia , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico , Oseltamivir/farmacologia , Influenza Humana/tratamento farmacológico , Guanidinas/farmacologia , Cicloexenos/uso terapêutico , Farmacorresistência Viral
16.
Virus Res ; 325: 199039, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36610656

RESUMO

Influenza infection causes substantial morbidity and mortality during seasonal epidemics and pandemics. Antivirals, including neuraminidase inhibitors, play an important role in the treatment of severely ill patients infected with influenza. Resistance is a key factor that can affect the efficacy of neuraminidase inhibitors (NAIs). It is a recommendation by regulatory authorities to monitor for resistance during the development of anti-influenza medications. An additional requirement by regulators is to examine amino acid sequences for minority species harbouring resistance substitutions. In a Phase III study of intravenous (IV) zanamivir respiratory samples were analysed for the presence of resistant quasi species using Next Generation Sequencing (NGS). In this study ten resistance substitutions, two of which were treatment emergent, were detected by NGS that otherwise would not have been detectable by Sanger sequencing. None of the substitutions were present at any other timepoints analysed. The effect these mutations have on clinical response is difficult to characterize; in fact, all patients from which these variants were isolated had a successful clinical outcome and the effect on clinical response was therefore likely minimal. Although NGS is becoming a routine method for nucleic acid sequencing and will detect substitutions previously undetected by Sanger sequencing, the value of this technique in identifying minority species with resistance substitutions that are clinically meaningful remains to be demonstrated, particularly with acute infections such as influenza.


Assuntos
Influenza Humana , Zanamivir , Humanos , Antivirais/farmacologia , Antivirais/uso terapêutico , Farmacorresistência Viral/genética , Inibidores Enzimáticos/farmacologia , Guanidinas/farmacologia , Influenza Humana/tratamento farmacológico , Neuraminidase/genética , Oseltamivir/farmacologia , Zanamivir/farmacologia , Zanamivir/uso terapêutico
17.
Int J Pharm ; 629: 122392, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36379395

RESUMO

Antiviral drugs play a major role in the control of seasonal influenza epidemics and may provide prophylactic and therapeutic benefits during an eventual pandemic. Among the neuraminidase inhibitors, zanamivir has been shown to be a potent inhibitor of influenza viruses, and similarly against emerging resistant strains. Despite its high antiviral efficiency, zanamivir suffers from poor intestinal permeability, therefore administered via inhalation. Enabling oral delivery of zanamivir will augment the available antiviral tools in clinical practice, increase patient compliance and ultimately improve public health. Encapsulation of hydrophilic drugs within double emulsions (DEs), is an efficacious approach to enhance the oral bioavailability of BCS Class III drugs, such as zanamivir. The objective of this research was to increase the intestinal absorption of zanamivir by means of compatible DEs. Two different types of stable DEs were prepared comprising different internal aqueous phases (W1). These micro-sized DEs showed high encapsulation efficacy (96.6-98.9 %) and markedlyretardedtherelease rateof the antiviral drug. Both types of the zanamivir loaded DEs (zDEs) significantly increased the transport ability of zanamivir across a parallel artificial membrane. Furthermore, in-situ perfusion of zDEs revealed outstanding permeability of zanamivir across the intestinal wall of rats. The zDEs containing carbomer gel (rather than carboxymethyl cellulose) as W1 obtained superior in-vivo effective permeability (Peff); yet, both zDEs exhibited higher Peff values (2-6-fold) than the low/high permeability marker (metoprolol). In conclusion, the DEs delivery system allowed overcoming the intestinal permeability barriers, towards successful oral administration of zanamivir.


Assuntos
Antivirais , Zanamivir , Ratos , Animais , Zanamivir/farmacologia , Antivirais/farmacologia , Emulsões , Absorção Intestinal , Inibidores Enzimáticos
18.
Molecules ; 27(18)2022 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-36144655

RESUMO

An epidemic of avian type H7N9 influenza virus, which took place in China in 2013, was enhanced by a naturally occurring R294K mutation resistant against Oseltamivir at the catalytic site of the neuraminidase. To cope with such drug-resistant neuraminidase mutations, we applied the molecular docking technique to evaluate the fitness of the available drugs such as Oseltamivir, Zanamivir, Peramivir, Laninamivir, L-Arginine and Benserazide hydrochloride concerning the N9 enzyme with single (R294K, R119K, R372K), double (R119_294K, R119_372K, R294_372K) and triple (R119_294_372K) mutations in the pocket. We found that the drugs Peramivir and Zanamivir score best amongst the studied compounds, demonstrating their high binding potential towards the pockets with the considered mutations. Despite the fact that mutations changed the shape of the pocket and reduced the binding strength for all drugs, Peramivir was the only drug that formed interactions with the key residues at positions 119, 294 and 372 in the pocket of the triple N9 mutant, while Zanamivir demonstrated the lowest RMSD value (0.7 Å) with respect to the reference structure.


Assuntos
Subtipo H7N9 do Vírus da Influenza A , Influenza Humana , Ácidos Carbocíclicos , Antivirais/química , Arginina/farmacologia , Benserazida/farmacologia , Benserazida/uso terapêutico , Farmacorresistência Viral/genética , Inibidores Enzimáticos/farmacologia , Guanidinas/farmacologia , Guanidinas/uso terapêutico , Humanos , Subtipo H7N9 do Vírus da Influenza A/genética , Subtipo H7N9 do Vírus da Influenza A/metabolismo , Influenza Humana/tratamento farmacológico , Simulação de Acoplamento Molecular , Mutação , Neuraminidase/química , Oseltamivir/farmacologia , Zanamivir/farmacologia
19.
Artigo em Inglês | MEDLINE | ID: mdl-36154657

RESUMO

As part of its role in the World Health Organization's (WHO) Global Influenza Surveillance and Response System (GISRS), the WHO Collaborating Centre for Reference and Research on Influenza in Melbourne received a total of 2,393 human influenza positive samples between 1 January 2020 and 31 December 2021 (2020: n = 2,021 samples; 2021: n = 372 samples). Viruses were analysed for their antigenic, genetic and antiviral susceptibility properties. Selected viruses were propagated in qualified cells or embryonated hen's eggs for potential use in seasonal influenza virus vaccines. During 2020-2021, influenza A viruses (A(H1N1)pdm09 in 2020 and A(H3N2) in 2021) predominated over influenza B viruses. In 2020, the majority of A(H1N1)pdm09, A(H3N2) and influenza B viruses analysed at the Centre were found to be antigenically similar to the respective WHO recommended vaccine strains for the southern hemisphere in 2020. In 2021, the majority of A(H1N1)pdm09 and A(H3N2) viruses were found to be antigenically distinct relative to the WHO recommended vaccine strains for the southern hemisphere in 2021. Of the influenza B viruses analysed at the Centre, 46.7% were found to be antigenically distinct to the respective WHO recommended vaccine strains. Of 1,538 samples tested for susceptibility to the neuraminidase inhibitors oseltamivir and zanamivir (in 2020, n = 1,374; in 2021, n = 164), two A(H1N1)pdm09 viruses showed highly reduced inhibition against oseltamivir, and one A(H1N1)pdm09 virus showed highly reduced inhibition against zanamivir. All of these samples were received in 2020.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Vírus da Influenza A Subtipo H3N2 , Vírus da Influenza B , Influenza Humana , Antivirais/farmacologia , Austrália/epidemiologia , Farmacorresistência Viral/genética , Humanos , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H3N2/genética , Vírus da Influenza B/genética , Vacinas contra Influenza , Influenza Humana/epidemiologia , Influenza Humana/virologia , Neuraminidase , Oseltamivir/farmacologia , Organização Mundial da Saúde , Zanamivir/farmacologia
20.
Eur J Med Chem ; 243: 114711, 2022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-36055001

RESUMO

Influenza with a tendency to cause pandemic and epidemic is an infectious disease with a high of morbidity and mortality. Neuraminidase (NA) inhibitors are proved to prevent and treat influenza. Among the four Neuraminidase inhibitors (NAIs) licensed, oseltamivir is most commonly used. With the extensive usage, several variants containing mutant NAs especially H274Y point mutation exhibit reduced susceptibility. In this review, we covered the current drugs available for influenza, the analysis of active site of NA, the mutant types of NAs and the molecular mechanism of drug resistance brought by H274Y mutant NAs. For recovering the susceptibility to oseltamivir, many series of oseltamivir analogues were designed. We present the details of the strategies of strengthening the interactions with S2 via introducing strong basic fragment, targeting additional subpockets and making full use of Zone X by modifying 3-pentyl of OC. PROTAC targeting NA and combination therapies are also introduced. Further, the advantages and disadvantages of these methods are also discussed.


Assuntos
Influenza Humana , Oseltamivir , Humanos , Oseltamivir/farmacologia , Oseltamivir/química , Neuraminidase/genética , Neuraminidase/química , Zanamivir/farmacologia , Mutação , Antivirais/farmacologia , Antivirais/química , Inibidores Enzimáticos/farmacologia , Guanidinas/farmacologia , Glicosídeo Hidrolases , Farmacorresistência Viral
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