RESUMO
Influenza viruses remain a major threat to human health. Four classes of drugs have been approved for the prevention and treatment of influenza infections. Oseltamivir, a neuraminidase inhibitor, is a first-line anti-influenza drug, and baloxavir is part of the newest generation of anti-influenza drugs that targets the viral polymerase. The emergence of drug resistance has reduced the efficacy of established antiviral drugs. Combination therapy is one of the options for controlling drug resistance and enhancing therapeutical efficacies. Here, we evaluate the antiviral effects of baloxavir combined with neuraminidase inhibitors (NAIs) against wild-type influenza viruses, as well as influenza viruses with drug-resistance mutations. The combination of baloxavir with NAIs led to significant synergistic effects; however, the combination of baloxavir with laninamivir failed to result in a synergistic effect on influenza B viruses. Considering the rapid emergence of drug resistance to baloxavir, we believe that these results will be beneficial for combined drug use against influenza.
Assuntos
Antivirais , Dibenzotiepinas , Farmacorresistência Viral , Sinergismo Farmacológico , Inibidores Enzimáticos , Morfolinas , Neuraminidase , Piridonas , Triazinas , Dibenzotiepinas/farmacologia , Antivirais/farmacologia , Triazinas/farmacologia , Morfolinas/farmacologia , Piridonas/farmacologia , Neuraminidase/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Humanos , Vírus da Influenza B/efeitos dos fármacos , Animais , Piridinas/farmacologia , Tiazóis/farmacologia , Guanidinas/farmacologia , Orthomyxoviridae/efeitos dos fármacos , Cães , Células Madin Darby de Rim Canino , Influenza Humana/tratamento farmacológico , Influenza Humana/virologia , Ácidos Siálicos , Vírus da Influenza A/efeitos dos fármacos , Tiepinas/farmacologia , Triazóis/farmacologia , Benzimidazóis/farmacologia , PiranosRESUMO
Despite much research, considerable data suggest that influenza virus remains a serious health problem because i) the effectiveness of current vaccines ranges only from 19% to 60%, ii) available therapies remain ineffective in advanced stages of disease, iii) death rates vary between 25,000 and 72,000/year in the United States, and iv) avian influenza strains are now being transmitted to dairy cattle that in turn are infecting humans. To address these concerns, we have developed zanDR, a bispecific small molecule that binds and inhibits viral neuraminidase expressed on both free virus and virus-infected cells and recruits naturally occurring anti-rhamnose and anti-dinitrophenyl (DNP) antibodies with rhamnose and DNP haptens. Because the neuraminidase inhibition replicates the chemotherapeutic mechanism of zanamivir and oseltamivir, while rhamnose and DNP recruit endogenous antibodies much like an anti-influenza vaccine, zanDR reproduces most of the functions of current methods of protection against influenza virus infections. Importantly, studies on cells in culture demonstrate that both of the above protective mechanisms remain highly functional in the zanDR conjugate, while studies in lethally infected mice with advanced-stage disease establish that a single intranasal dose of zanDR not only yields 100% protection but also reduces lung viral loads faster and ~1,000× more thoroughly than current antiviral therapies. Since zanDR also lowers secretion of proinflammatory cytokines and protects against virus-induced damage to the lungs better than current therapies, we suggest that combining an immunotherapy with a chemotherapy in single pharmacological agent constitutes a promising approach for treating the more challenging forms of influenza.
Assuntos
Infecções por Orthomyxoviridae , Animais , Camundongos , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/tratamento farmacológico , Infecções por Orthomyxoviridae/virologia , Humanos , Antivirais/farmacologia , Influenza Humana/imunologia , Influenza Humana/tratamento farmacológico , Influenza Humana/prevenção & controle , Neuraminidase/imunologia , Neuraminidase/antagonistas & inibidores , Cães , Feminino , Camundongos Endogâmicos BALB C , Anticorpos Antivirais/imunologiaRESUMO
The prevalent human pathogen, mumps virus (MuV; orthorubulavirus parotitidis) causes various complications and serious sequelae, such as meningitis, encephalitis, deafness, and impaired fertility. Direct-acting antivirals (DAAs) targeting MuV which can prevent mumps and mumps-associated complications and sequelae are yet to be developed. Paramyxoviridae family members, such as MuV, possess viral surface hemagglutinin-neuraminidase (HN) protein with sialidase activity which facilitates efficient viral replication. Therefore, to develop DAAs targeting MuV we synthesized MuV sialidase inhibitors. It is proposed that the viral HN has a single functional site for N-acetylneuraminic acid (Neu5Ac) binding and sialidase activity. Further, the known MuV sialidase inhibitor is an analog of Neu5Ac-2,3-didehydro-2-deoxy-N-acetylneuraminic acid (DANA)-which lacks potency. DANA derivatives with higher MuV sialidase inhibitory potency are lacking. The MuV-HN-Neu5Ac binding site has a hydrophobic cavity adjacent to the C4 position of Neu5Ac. Exploiting this, here, we synthesized DANA derivatives with increasing hydrophobicity at its C4 position and created 3 novel sialidase inhibitors (Compounds 1, 2, and 3) with higher specificity for MuV-HN than DANA; they inhibited MuV replication step to greater extent than DANA. Furthermore, they also inhibited hemagglutination and the MuV infection step. The insight-that these 3 novel DANA derivatives possess linear hydrocarbon groups at the C4-hydroxyl group of DANA-could help develop highly potent sialidase inhibitors with high specificity for MuV sialidase, which may function as direct-acting MuV-specific antivirals.
Assuntos
Antivirais , Vírus da Caxumba , Neuraminidase , Replicação Viral , Vírus da Caxumba/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos , Neuraminidase/antagonistas & inibidores , Neuraminidase/metabolismo , Antivirais/farmacologia , Antivirais/química , Antivirais/síntese química , Humanos , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/química , Inibidores Enzimáticos/síntese química , Animais , Chlorocebus aethiops , Proteína HN/metabolismo , Proteína HN/química , Células Vero , Caxumba/tratamento farmacológico , Caxumba/virologiaRESUMO
Sporadically and periodically, influenza outbreaks threaten global health and the economy. Antigen drift-induced influenza virus mutations hamper antiviral drug development. Thus, a novel antiviral agent is urgently needed to address medication inefficacy issues. Herein, sixteen new quinoline-triazole hybrids 6a-h and 9a-h were prepared and evaluated in vitro against the H1N1 virus. In particular, 6d, 6e, and 9b showed promising H1N1 antiviral activity with selective index (SI) CC50/IC50 values of 15.8, 37, and 29.15. After that, the inhibition rates for various mechanisms of action (virus replication, adsorption, and virucidal activity) were investigated for the most efficient candidates 6d, 6e, and 9b. Additionally, their ability to inhibit neuraminidase was evaluated. With an IC50 value of 0.30 µM, hybrid 6d demonstrated effective and comparable inhibitory activity to Oseltamivir. Ultimately, molecular modeling investigations, encompassing molecular docking and molecular dynamic simulations, were conducted to provide a scientific basis for the observed antiviral results.
Assuntos
Antivirais , Relação Dose-Resposta a Droga , Inibidores Enzimáticos , Vírus da Influenza A Subtipo H1N1 , Neuraminidase , Quinolinas , Triazóis , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Vírus da Influenza A Subtipo H1N1/enzimologia , Antivirais/farmacologia , Antivirais/química , Antivirais/síntese química , Quinolinas/química , Quinolinas/farmacologia , Quinolinas/síntese química , Neuraminidase/antagonistas & inibidores , Neuraminidase/metabolismo , Triazóis/química , Triazóis/farmacologia , Triazóis/síntese química , Relação Estrutura-Atividade , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/química , Inibidores Enzimáticos/síntese química , Estrutura Molecular , Humanos , Testes de Sensibilidade Microbiana , Descoberta de Drogas , Simulação de Acoplamento MolecularRESUMO
Neuraminidase (NA) has been well-studied as a therapeutic target for Influenza. However, resistance to the influenza virus has been observed recently. Out of special interest in the utilization of dietary antivirals from citrus, in vitro inhibition activity against NA and in silico studies including molecular docking, molecular dynamic simulation, and a predictive ADMET study, were performed on five citrus-derived flavanones. Encouragingly, citrus-derived flavanones displayed comparable or even more potent in vitro inhibitory activity than oseltamivir carboxylate against NA. Orange peel extract exhibited higher activity than hesperidin. Among the tested compounds, neohesperidin, forming strong hydrogen-bonding interactions with key arginine residues, exhibited the most effective inhibitory activity against NAs from C. perfringens, consistent with the results of molecular dynamics simulations. Although the molecular docking results were inconsistent with the in vitro activity, the binding energy was identical against the wild-type and mutant, suggesting a lower likelihood of developing drug resistance. Moreover, predictive ADMET studies showed favorable pharmacokinetic properties for the tested compounds. Overall, citrus fruit peel emerges as a promising dietary supplement for prevention and treatment of influenza. These findings elucidate the impact of flavanones on NA activity, and the analysis of their binding modes provides valuable insights into the mechanism of NA inhibition.
Assuntos
Antivirais , Citrus , Inibidores Enzimáticos , Flavanonas , Simulação de Acoplamento Molecular , Neuraminidase , Neuraminidase/antagonistas & inibidores , Neuraminidase/metabolismo , Flavanonas/farmacologia , Flavanonas/química , Citrus/química , Antivirais/farmacologia , Antivirais/química , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/química , Relação Estrutura-Atividade , Simulação de Dinâmica Molecular , Estrutura Molecular , Relação Dose-Resposta a Droga , Testes de Sensibilidade Microbiana , HumanosRESUMO
Human neuraminidases play critical roles in many physiological and pathological processes. Humans have four isoenzymes of NEU, making selective inhibitors important tools to investigate the function of individual isoenzymes. A typical scaffold for NEU inhibitors is 2-deoxy-2,3-didehydro-N-acetylneuraminic acid (DANA) where C9 modifications can be critical for potency and selectivity against human NEU. To design improved DANA analogues, we generated a library of compounds with either a short alkyl chain or a biphenyl substituent linked to the C9 position through one of six amide bioisosteres. Bioisostere linkers included triazole, urea, thiourea, carbamate, thiocarbamate, and sulfonamide groups. Within this library, we identified a C9 biphenyl carbamate derivative (963) that showed high selectivity and potency for NEU3 (Ki = 0.12 ± 0.01 µM). In contrast, NEU1 and NEU4 isoenzymes preferred amide and triazole linkers, respectively. Finally, analogues with urea, sulfonamide, and amide linkers showed enhanced inhibitory activity for a bacterial NEU, NanI from Clostridium perfringens.
Assuntos
Inibidores Enzimáticos , Neuraminidase , Humanos , Neuraminidase/antagonistas & inibidores , Neuraminidase/metabolismo , Relação Estrutura-Atividade , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/química , Inibidores Enzimáticos/síntese química , Clostridium perfringens/enzimologia , Clostridium perfringens/efeitos dos fármacos , Ácido N-Acetilneuramínico/química , Ácido N-Acetilneuramínico/farmacologia , Ácido N-Acetilneuramínico/análogos & derivados , Ácidos Neuramínicos/química , Ácidos Neuramínicos/metabolismoRESUMO
Influenza viruses that cause seasonal and pandemic flu are a permanent health threat. The surface glycoprotein, neuraminidase, is crucial for the infectivity of the virus and therefore an attractive target for flu drug discovery campaigns. We have designed and synthesized more than 40 3-indolinone derivatives. We mainly investigated the role of substituents at the 2 position of the core as well as the introduction of substituents or a nitrogen atom in the fused phenyl ring of the core for inhibition of influenza virus neuraminidase activity and replication in vitro and in vivo. After evaluating the compounds for their ability to inhibit the viral neuraminidase, six potent inhibitors 3c, 3e, 7c, 12o, 12v, 18d were progressed to evaluate for cytotoxicity and inhibition of influenza virus A/PR/8/34 replication in in MDCK cells. Two hit compounds 3e and 12o were tested in an animal model of influenza virus infection. Molecular mechanism of the 3-indolinone derivatives interactions with the neuraminidase was revealed in molecular dynamic simulations. Proposed inhibitors bind to the 430-cavity that is different from the conventional binding site of commercial compounds. The most promising 3-indolinone inhibitors demonstrate stronger interactions with the neuraminidase in molecular models that supports proposed binding site.
Assuntos
Antivirais , Inibidores Enzimáticos , Indóis , Neuraminidase , Neuraminidase/antagonistas & inibidores , Neuraminidase/metabolismo , Antivirais/farmacologia , Antivirais/química , Antivirais/síntese química , Indóis/farmacologia , Indóis/química , Indóis/síntese química , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/química , Inibidores Enzimáticos/síntese química , Animais , Cães , Relação Estrutura-Atividade , Células Madin Darby de Rim Canino , Estrutura Molecular , Modelos Moleculares , Vírus da Influenza A/efeitos dos fármacos , Vírus da Influenza A/enzimologia , Relação Dose-Resposta a Droga , Química Farmacêutica , Humanos , Camundongos , Testes de Sensibilidade Microbiana , Replicação Viral/efeitos dos fármacosRESUMO
Influenza remains a global public health threat, and the development of new antivirals is crucial to combat emerging drug-resistant influenza strains. In this study, we report the synthesis and evaluation of a sialyl lactosyl (TS)-bovine serum albumin (BSA) conjugate as a potential multivalent inhibitor of the influenza virus. The key trisaccharide component, TS, was efficiently prepared via a chemoenzymatic approach, followed by conjugation to dibenzocyclooctyne-modified BSA via a strain-promoted azide-alkyne cycloaddition reaction. Biophysical and biochemical assays, including surface plasmon resonance, isothermal titration calorimetry, hemagglutination inhibition, and neuraminidase inhibition, demonstrated the strong binding affinity of TS-BSA to the hemagglutinin (HA) and neuraminidase (NA) proteins of the influenza virus as well as intact virion particles. Notably, TS-BSA exhibited potent inhibitory activity against viral entry and release, preventing cytopathic effects in cell culture. This multivalent presentation strategy highlights the potential of glycocluster-based antivirals for combating influenza and other drug-resistant viral strains.
Assuntos
Antivirais , Soroalbumina Bovina , Antivirais/farmacologia , Antivirais/química , Antivirais/síntese química , Soroalbumina Bovina/química , Soroalbumina Bovina/metabolismo , Animais , Humanos , Influenza Humana/tratamento farmacológico , Relação Estrutura-Atividade , Relação Dose-Resposta a Droga , Estrutura Molecular , Cães , Bovinos , Testes de Sensibilidade Microbiana , Neuraminidase/antagonistas & inibidores , Neuraminidase/metabolismo , Internalização do Vírus/efeitos dos fármacos , Células Madin Darby de Rim Canino/efeitos dos fármacos , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , GlicosídeosRESUMO
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/enzimologiaRESUMO
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 50RESUMO
Aim: The purpose of this study is to design and synthesize a new series of sulfamethazine derivatives as potent neuraminidase inhibitors. Materials & methods: A sulfamethazine lead compound, ZINC670537, was first identified by structure-based virtual screening technique, then some novel inhibitors X1-X10 based on ZINC670537 were designed and synthesized. Results: Compound X3 exerts the most good potency in inhibiting the wild-type H5N1 NA (IC50 = 6.74 µM) and the H274Y mutant NA (IC50 = 21.09 µM). 150-cavity occupation is very important in determining activities of these inhibitors. The sulfamethazine moiety also plays an important role. Conclusion: Compound X3 maybe regard as a good anti-influenza candidate to preform further study.
[Box: see text].
Assuntos
Antivirais , Desenho de Fármacos , Inibidores Enzimáticos , Virus da Influenza A Subtipo H5N1 , Neuraminidase , Sulfametazina , Neuraminidase/antagonistas & inibidores , Neuraminidase/metabolismo , Sulfametazina/farmacologia , Sulfametazina/síntese química , Sulfametazina/química , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Antivirais/farmacologia , Antivirais/síntese química , Antivirais/química , Virus da Influenza A Subtipo H5N1/efeitos dos fármacos , Virus da Influenza A Subtipo H5N1/enzimologia , Relação Estrutura-Atividade , Humanos , Estrutura Molecular , Simulação de Acoplamento MolecularRESUMO
The frequent mutations of influenza A virus (IAV) have led to an urgent need for the development of innovative antiviral drugs. Glycopolymers offer significant advantages in biomedical applications owing to their biocompatibility and structural diversity. However, the primary challenge lies in the design and synthesis of well-defined glycopolymers to precisely control their biological functionalities. In this study, functional glycopolymers with sulfated fucose and 6'-sialyllactose were successfully synthesized through ring-opening metathesis polymerization and a postmodification strategy. The optimized heteropolymer exhibited simultaneous targeting of hemagglutinin and neuraminidase on the surface of IAV, as evidenced by MU-NANA assay and hemagglutination inhibition data. Antiviral experiments demonstrated that the glycopolymer displayed broad and efficient inhibitory activity against wild-type and mutant strains of H1N1 and H3N2 subtypes in vitro, thereby establishing its potential as a dual-targeted inhibitor for combating IAV resistance.
Assuntos
Antivirais , Fucose , Vírus da Influenza A Subtipo H1N1 , Lactose , Antivirais/farmacologia , Antivirais/química , Antivirais/síntese química , Lactose/análogos & derivados , Lactose/química , Lactose/farmacologia , Fucose/química , Fucose/análogos & derivados , Fucose/farmacologia , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Vírus da Influenza A Subtipo H3N2/efeitos dos fármacos , Farmacorresistência Viral/efeitos dos fármacos , Humanos , Neuraminidase/antagonistas & inibidores , Neuraminidase/metabolismo , Vírus da Influenza A/efeitos dos fármacos , Células Madin Darby de Rim Canino , Animais , Cães , Polímeros/farmacologia , Polímeros/químicaRESUMO
Selaginella tamariscina is a perennial plant that is used for diverse diseases. This study investigated whether Selaginella tamariscina has an antiviral effect against influenza A virus (IAV) infection. We used green fluorescent protein (GFP)-tagged influenza A virus (IAV) to examine the effect of Selaginella tamariscina ethanol extract (STE) on influenza viral infection. Fluorescence microscopy and flow cytometry showed that STE potently represses GFP expression by the virus, dose-dependently. STE significantly inhibited the expression of the IAV M2, NP, HA, NA, NS1, and PB2 proteins. Time-of-addition and hemagglutination inhibition assays showed that STE has an inhibitory effect on hemagglutinin and viral binding on the cells at an early infection time. In addition, STE exerted a suppressive effect on the neuraminidase activity of the H1N1 and H3N2 IAVs. Furthermore, dose-dependently, STE inhibited the cytopathic effect induced by H3N2, as well as by H1N1 IAV. Especially in the presence of 200 µg/mL STE, the cytopathic effect was completely blocked. Our findings suggest that STE has antiviral efficacy against IAV infection; thus, it could be developed as a natural IAV inhibitor.
Assuntos
Antivirais , Etanol , Vírus da Influenza A Subtipo H1N1 , Vírus da Influenza A Subtipo H3N2 , Neuraminidase , Extratos Vegetais , Selaginellaceae , Neuraminidase/antagonistas & inibidores , Neuraminidase/metabolismo , Extratos Vegetais/farmacologia , Antivirais/farmacologia , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Humanos , Vírus da Influenza A Subtipo H3N2/efeitos dos fármacos , Animais , Células Madin Darby de Rim Canino , Selaginellaceae/química , Cães , Vírus da Influenza A/efeitos dos fármacos , Hemaglutininas/metabolismo , Influenza Humana/tratamento farmacológicoRESUMO
This study investigates quercetin complexes as potential synergistic agents against the important respiratory pathogen Streptococcus pneumoniae. Six quercetin complexes (QCX1-6) were synthesized by reacting quercetin with various metal salts and boronic acids and characterized using FTIR spectroscopy. Their antibacterial activity alone and in synergism with antibiotics was evaluated against S. pneumoniae ATCC 49619 using disc diffusion screening, broth microdilution MIC determination, and checkerboard assays. Complexes QCX-3 and QCX-4 demonstrated synergy when combined with levofloxacin via fractional inhibitory concentration indices ≤ 0.5 as confirmed by time-kill kinetics. Molecular docking elucidated interactions of these combinations with virulence enzymes sortase A and sialidase. A biofilm inhibition assay found the synergistic combinations more potently reduced biofilm formation versus monotherapy. Additionally, gene-gene interaction networks, biological activity predictions and in-silico toxicity profiling provided insights into potential mechanisms of action and safety.
Assuntos
Antibacterianos , Biofilmes , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Quercetina , Streptococcus pneumoniae , Streptococcus pneumoniae/efeitos dos fármacos , Quercetina/farmacologia , Quercetina/química , Antibacterianos/farmacologia , Antibacterianos/química , Biofilmes/efeitos dos fármacos , Sinergismo Farmacológico , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/química , Proteínas de Bactérias/antagonistas & inibidores , Cisteína Endopeptidases/metabolismo , Cisteína Endopeptidases/química , Aminoaciltransferases/antagonistas & inibidores , Aminoaciltransferases/metabolismo , Neuraminidase/antagonistas & inibidores , Neuraminidase/metabolismoRESUMO
Since May 2023, a novel combination of neuraminidase mutations, I223V + S247N, has been detected in influenza A(H1N1)pdm09 viruses collected in countries spanning 5 continents, mostly in Europe (67/101). The viruses belong to 2 phylogenetically distinct groups and display ≈13-fold reduced inhibition by oseltamivir while retaining normal susceptibility to other antiviral drugs.
Assuntos
Antivirais , Farmacorresistência Viral , Vírus da Influenza A Subtipo H1N1 , Influenza Humana , Neuraminidase , Oseltamivir , Filogenia , Oseltamivir/farmacologia , Oseltamivir/uso terapêutico , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Vírus da Influenza A Subtipo H1N1/genética , Humanos , Antivirais/farmacologia , Antivirais/uso terapêutico , Influenza Humana/virologia , Influenza Humana/tratamento farmacológico , Influenza Humana/epidemiologia , Neuraminidase/antagonistas & inibidores , Neuraminidase/genética , Farmacorresistência Viral/genética , MutaçãoRESUMO
BACKGROUND: Bacteria within biofilms are thousand times more resistant to antibiotics. Neuraminidase is a crucial enzyme for bacterial adhesion and biofilm formation, it hydrolyzes glycosidic residue of glycoproteins, glycolipids, and oligosaccharides. Coreopsis lanceolata L. flowers may have a significant potential of bacterial neuraminidase (BNA) inhibition because of high natural abundance of chalcones. PURPOSE: The investigation of bacterial biofilm inhibitors has emerged as a novel therapeutic strategy against antibiotic resistance. Therefore, individual chalcones were isolated from C. lanceolata and their capacity to inhibit BNA and formation of Escherichia coli biofilm were evaluated. METHODS: Different chromatographic techniques were used to isolate the compounds (1-12). Enzyme inhibition and detailed kinetic behavior of compounds was determined by estimation of kinetic parameters (Michaelis-Menten constants (Km), maximum velocity (Vmax), dissociation constant for binding with the free enzyme (KI) and enzyme-substate complex (KIS)). Binding affinities (KSV) and binding modes of inhibitors were elucidated by fluorescence quenching and molecular docking, respectively. The natural abundance of chalcones was established through UPLC-Q-TOF/MS. The most potent inhibitor (1) was tested for its ability to inhibit the formation of E. coli biofilm, which was examined by crystal violet assay, scanning electron microscope (SEM) and confocal laser scanning microscope (CLSM). RESULTS: A series of eight chalcones (1-8) and four chalcone glucosides (9-12), inhibited BNA in a dose-dependent manner with IC50 of 8.3 â¼ 77.0 µM. The most potent chalcones were butein (1, IC50 = 8.3 µM) and its glucoside 9 (IC50 = 13.8 µM). The aglycones (1-8) showed non-competitive inhibition, while chalcone glucosides (9-12) displayed a mixed type I (KI < KIS). Inhibitory behaviors were doubly confirmed by KSV and matched with tendency of IC50. The functional group responsible for BNA inhibition were disclosed as 4'-hydroxyl group on B-ring by structure activity relationship (SAR) and molecular docking experiments. Butein (1) suppressed E. coli biofilm formation by > 50 % at 100 µM according to crystal violet assay, which was confirmed by SEM and CLSM imaging. CONCLUSION: The results showed that chalcones (1-8) and chalcone glucosides (9-12), metabolites isolated from the flowers of C. lanceolata, had BNA inhibitory and antibiofilm formation effect on E. coli.
Assuntos
Antibacterianos , Biofilmes , Chalconas , Coreopsis , Escherichia coli , Flores , Neuraminidase , Antibacterianos/farmacologia , Antibacterianos/química , Biofilmes/efeitos dos fármacos , Chalconas/farmacologia , Chalconas/química , Coreopsis/química , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/química , Escherichia coli/efeitos dos fármacos , Flores/química , Cinética , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Neuraminidase/antagonistas & inibidores , Extratos Vegetais/farmacologia , Extratos Vegetais/químicaRESUMO
INTRODUCTION: Influenza affects individuals of all ages and poses a significant threat during pandemics, epidemics, and sporadic outbreaks. Neuraminidase inhibitors (NAIs) are currently the first choice in the treatment and prevention of influenza, but their use can be hindered by viral resistance. AREAS COVERED: This review summarizes current NAIs pharmacological profiles, their current place in therapy, and the mechanisms of viral resistance and outlines possible new indications, ways of administration, and novel candidate NAIs compounds. EXPERT OPINION: NAIs represent a versatile group of compounds with diverse administration methods and pharmacokinetics. While the prevalence of influenza virus resistance to NAIs remains low, there is heightened vigilance due to the pandemic potential of influenza. Several novel NAIs and derivatives are currently under assessment at various stages of development for the treatment and prevention of influenza.
Assuntos
Antivirais , Farmacorresistência Viral , Inibidores Enzimáticos , Influenza Humana , Neuraminidase , Humanos , Neuraminidase/antagonistas & inibidores , Influenza Humana/tratamento farmacológico , Antivirais/uso terapêutico , Antivirais/farmacologia , Inibidores Enzimáticos/uso terapêutico , Inibidores Enzimáticos/farmacologia , Desenvolvimento de Medicamentos , AnimaisRESUMO
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 , MasculinoRESUMO
Influenza A viruses (IAVs) continue to pose a huge threat to public health, and their prevention and treatment remain major international issues. Neuraminidase (NA) is the second most abundant surface glycoprotein on influenza viruses, and antibodies to NA have been shown to be effective against influenza infection. In this study, we generated a monoclonal antibody (mAb), named FNA1, directed toward N1 NAs. FNA1 reacted with H1N1 and H5N1 NA, but failed to react with the NA proteins of H3N2 and H7N9. In vitro, FNA1 displayed potent antiviral activity that mediated both NA inhibition (NI) and blocking of pseudovirus release. Moreover, residues 219, 254, 358, and 388 in the NA protein were critical for FNA1 binding to H1N1 NA. However, further validation is necessary to confirm whether FNA1 mAb is indeed a good inhibitor against NA for application against H1N1 and H5N1 viruses.
Assuntos
Anticorpos Monoclonais , Vírus da Influenza A Subtipo H1N1 , Neuraminidase , Neuraminidase/imunologia , Neuraminidase/metabolismo , Neuraminidase/antagonistas & inibidores , Anticorpos Monoclonais/imunologia , Vírus da Influenza A Subtipo H1N1/imunologia , Humanos , Animais , Anticorpos Antivirais/imunologia , Camundongos , Virus da Influenza A Subtipo H5N1/imunologia , Camundongos Endogâmicos BALB C , Antivirais/farmacologia , Proteínas Virais/imunologia , Proteínas Virais/metabolismo , Vírus da Influenza A Subtipo H3N2/imunologia , Subtipo H7N9 do Vírus da Influenza A/imunologiaRESUMO
BACKGROUND: An analysis was conducted in Japan to determine the most cost-effective neuraminidase inhibitor for the treatment of influenza virus infections from the healthcare payer's standpoint. OBJECTIVE: This study reanalysed the findings of a previous study that had some limitations (no probabilistic sensitivity analysis and quality of life scores measured by the EQ-5D-3L instead of the EQ-5D-5L) and used a decision tree model with only three health conditions. METHODS: This study incorporated new data from a network meta-analysis study into the first examination. The second examination involved constructing a new decision tree model encompassing seven health conditions and identifying costs, which consisted of medical costs and drug prices based on the 2020 version of the Japanese medical fee index. Effectiveness outcomes were measured using EQ-5D-5L questionnaires for adult patients with a history of influenza virus infections within a 14-day time horizon. Deterministic and probabilistic sensitivity analyses were performed to examine the uncertainty. RESULTS: In the first examination, the base-case cost-effectiveness analysis confirmed that oseltamivir outperformed laninamivir, zanamivir and peramivir, making it the most cost-effective neuraminidase inhibitor. The second examination revealed that oseltamivir dominated the other agents. Both deterministic and probabilistic sensitivity analyses showed robust results that validated oseltamivir as the most cost effective among the four neuraminidase inhibitors. CONCLUSIONS: This study thus reaffirms oseltamivir's position as the most cost-effective neuraminidase inhibitor for the treatment of influenza virus infections in Japan from the perspective of healthcare payment. These findings can help decision makers and healthcare providers in Japan.