RESUMO
The nucleoprotein (NP) of influenza A virus (IAV) required for IAV replication is a promising target for new antivirals. We previously identified by in silico screening naproxen being a dual inhibitor of NP and cyclooxygenase COX2, thus combining antiviral and anti-inflammatory effects. However, the recently shown strong COX2 antiviral potential makes COX2 inhibition undesirable. Here we designed and synthesized two new series of naproxen analogues called derivatives 2, 3, and 4 targeting highly conserved residues of the RNA binding groove, stabilizing NP monomer without inhibiting COX2. Derivative 2 presented improved antiviral effects in infected cells compared to that of naproxen and afforded a total protection of mice against a lethal viral challenge. Derivative 4 also protected infected cells challenged with circulating 2009-pandemic and oseltamivir-resistant H1N1 virus. This improved antiviral effect likely results from derivatives 2 and 4 inhibiting NP-RNA and NP-polymerase acidic subunit PA N-terminal interactions.
Assuntos
Antivirais/química , Antivirais/farmacologia , Inibidores de Ciclo-Oxigenase 2/farmacologia , Vírus da Influenza A/efeitos dos fármacos , Naproxeno/análogos & derivados , Células A549 , Animais , Sítios de Ligação , Inibidores de Ciclo-Oxigenase 2/química , Cães , Desenho de Fármacos , Reposicionamento de Medicamentos , Farmacorresistência Viral/efeitos dos fármacos , Feminino , Humanos , Vírus da Influenza A/patogenicidade , Influenza Humana/tratamento farmacológico , Influenza Humana/patologia , Células Madin Darby de Rim Canino , Camundongos Endogâmicos C57BL , Simulação de Acoplamento Molecular , Naproxeno/farmacologia , Proteínas do Nucleocapsídeo , Oseltamivir/farmacologia , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/metabolismo , Ressonância de Plasmônio de Superfície , Proteínas do Core Viral/química , Proteínas do Core Viral/metabolismoRESUMO
New 1-[1-(1H-indol-3-yl) alkyl]-1H-indoles, surprisingly, have been obtained from the addition of indole to a variety of aldehydes under neat conditions. CaO, present in excess, was fundamental for carrying out the reaction with paraformaldehyde. Under the same reaction conditions, aromatic and heteroaromatic aldehydes afforded only classical bis (indolyl) aryl indoles. In this paper, the role of CaO, together with the regiochemistry and the mechanism of the reaction, are discussed in detail. The effect of some selected 3,3'- and 1,3'-diindolyl methane derivatives on cell proliferation of the hepatoma cell line FaO was also evaluated.
Assuntos
Aldeídos/química , Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Indóis/síntese química , Indóis/farmacologia , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Indóis/química , Neoplasias Hepáticas , Espectroscopia de Ressonância Magnética , Estrutura Molecular , SolventesRESUMO
The nucleoprotein (NP) binds the viral RNA genome as oligomers assembled with the polymerase in a ribonucleoprotein complex required for transcription and replication of influenza A virus. Novel antiviral candidates targeting the nucleoprotein either induced higher order oligomers or reduced NP oligomerization by targeting the oligomerization loop and blocking its insertion into adjacent nucleoprotein subunit. In this study, we used a different structure-based approach to stabilize monomers of the nucleoprotein by drugs binding in its RNA-binding groove. We recently identified naproxen as a drug competing with RNA binding to NP with antiinflammatory and antiviral effects against influenza A virus. Here, we designed novel derivatives of naproxen by fragment extension for improved binding to NP. Molecular dynamics simulations suggested that among these derivatives, naproxen A and C0 were most promising. Their chemical synthesis is described. Both derivatives markedly stabilized NP monomer against thermal denaturation. Naproxen C0 bound tighter to NP than naproxen at a binding site predicted by MD simulations and shown by competition experiments using wt NP or single-point mutants as determined by surface plasmon resonance. MD simulations suggested that impeded oligomerization and stabilization of monomeric NP is likely to be achieved by drugs binding in the RNA grove and inducing close to their binding site conformational changes of key residues hosting the oligomerization loop as observed for the naproxen derivatives. Naproxen C0 is a potential antiviral candidate blocking influenza nucleoprotein function.
Assuntos
Antivirais/química , Vírus da Influenza A/química , Influenza Humana/virologia , Naproxeno/química , Nucleoproteínas/química , Antivirais/uso terapêutico , Sítios de Ligação , Humanos , Vírus da Influenza A/efeitos dos fármacos , Influenza Humana/tratamento farmacológico , Simulação de Dinâmica Molecular , Naproxeno/análogos & derivados , Naproxeno/uso terapêutico , Multimerização Proteica , RNA Viral/químicaRESUMO
A mild and versatile method for the synthesis of some novel indole-1-carbinols has been developed via one-pot reaction of indoles and paraformaldehyde in the presence of an excess of CaO, MgO, ZnO or TiO(2). The solvent-free reaction provided all the indole derivatives in moderate to good yields and short reaction times. Moreover, the effect of some selected indole-1-carbinols on cell proliferation of the hepatoma cell line FaO was evaluated.
