RESUMEN

Drug resistance to commercially available antimalarials is a major obstacle in malaria control and elimination, creating the need to find new antiparasitic compounds with novel mechanisms of action. The success of kinase inhibitors for oncological treatments has paved the way for the exploitation of protein kinases as drug targets in various diseases, including malaria. Casein kinases are ubiquitous serine/threonine kinases involved in a wide range of cellular processes such as mitotic checkpoint signaling, DNA damage response, and circadian rhythm. In Plasmodium, it is suggested that these protein kinases are essential for both asexual and sexual blood-stage parasites, reinforcing their potential as targets for multi-stage antimalarials. To identify new putative PfCK2α inhibitors, we utilized an in silico chemogenomic strategy involving virtual screening with docking simulations and quantitative structure-activity relationship predictions. Our investigation resulted in the discovery of a new quinazoline molecule (542), which exhibited potent activity against asexual blood stages and a high selectivity index (>100). Subsequently, we conducted chemical-genetic interaction analysis on yeasts with mutations in casein kinases. Our chemical-genetic interaction results are consistent with the hypothesis that 542 inhibits yeast Cka1, which has a hinge region with high similarity to PfCK2α. This finding is in agreement with our in silico results suggesting that 542 inhibits PfCK2α via hinge region interaction.

Asunto(s)

Antimaláricos , Malaria Falciparum , Malaria , Plasmodium , Antimaláricos/farmacología , Quinasa de la Caseína II/antagonistas & inhibidores , Malaria/tratamiento farmacológico , Malaria/parasitología , Malaria Falciparum/parasitología , Plasmodium/metabolismo , Plasmodium falciparum

RESUMEN

Zika virus (ZIKV) infection is associated with severe neurological disorders and congenital malformation. Despite efforts to eradicate the disease, there is still neither vaccine nor approved drugs to treat ZIKV infection. The NS2B-NS3 protease is a validated drug target since it is essential to polyprotein virus maturation. In the present study, we describe an experimental screening of 2,320 compounds from the chemical library of the Muséum National d'Histoire Naturelle of Paris on ZIKV NS2B-NS3 protease. A total of 96 hits were identified with 90% or more of inhibitory activity at 10 µM. Amongst the most active compounds, five were analyzed for their inhibitory mechanisms by kinetics assays and computational approaches such as molecular docking. 2-(3-methoxyphenoxy) benzoic acid (compound 945) show characteristics of a competitive inhibition (Ki = 0.49 µM) that was corroborated by its molecular docking at the active site of the NS2B-NS3 protease. Taxifolin (compound 2292) behaves as an allosteric inhibitor whereas 3,8,9-trihydroxy-2-methyl-1H-phenalen-1-one (compound 128), harmol (compound 368) and anthrapurpurin (compound 1499) show uncompetitive inhibitions. These new NS2B-NS3 protease inhibitors are valuable hits to further hit-to-lead optimization.

Asunto(s)

Infección por el Virus Zika , Virus Zika , Humanos , Simulación del Acoplamiento Molecular , Proteínas no Estructurales Virales/química , Serina Endopeptidasas/química , Inhibidores de Proteasas/farmacología , Inhibidores de Proteasas/química , Péptido Hidrolasas , Antivirales/farmacología , Antivirales/química

RESUMEN

Although the past epidemic of Zika virus (ZIKV) resulted in severe neurological consequences for infected infants and adults, there are still no approved drugs to treat ZIKV infection. In this study, we applied computational approaches to screen an in-house database of 77 natural and semi-synthetic compounds against ZIKV NS5 RNA-dependent RNA-polymerase (NS5 RdRp), an essential protein for viral RNA elongation during the replication process. For this purpose, we integrated computational approaches such as binding-site conservation, chemical space analysis and molecular docking. As a result, we prioritized nine virtual hits for experimental evaluation. Enzymatic assays confirmed that pedalitin and quercetin inhibited ZIKV NS5 RdRp with IC50 values of 4.1 and 0.5 µM, respectively. Moreover, pedalitin also displayed antiviral activity on ZIKV infection with an EC50 of 19.28 µM cell-based assays, with low toxicity in Vero cells (CC50 = 83.66 µM) and selectivity index of 4.34. These results demonstrate the potential of the natural compounds pedalitin and quercetin as candidates for structural optimization studies towards the discovery of new anti-ZIKV drug candidates.

RESUMEN

The Zika virus (ZIKV) is a neurotropic arbovirus considered a global threat to public health. Although there have been several efforts in drug discovery projects for ZIKV in recent years, there are still no antiviral drugs approved to date. Here, we describe the results of a global collaborative crowdsourced open science project, the OpenZika project, from IBM's World Community Grid (WCG), which integrates different computational and experimental strategies for advancing a drug candidate for ZIKV. Initially, molecular docking protocols were developed to identify potential inhibitors of ZIKV NS5 RNA-dependent RNA polymerase (NS5 RdRp), NS3 protease (NS2B-NS3pro), and NS3 helicase (NS3hel). Then, a machine learning (ML) model was built to distinguish active vs inactive compounds for the cytoprotective effect against ZIKV infection. We performed three independent target-based virtual screening campaigns (NS5 RdRp, NS2B-NS3pro, and NS3hel), followed by predictions by the ML model and other filters, and prioritized a total of 61 compounds for further testing in enzymatic and phenotypic assays. This yielded five non-nucleoside compounds which showed inhibitory activity against ZIKV NS5 RdRp in enzymatic assays (IC50 range from 0.61 to 17 µM). Two compounds thermally destabilized NS3hel and showed binding affinity in the micromolar range (Kd range from 9 to 35 µM). Moreover, the compounds LabMol-301 inhibited both NS5 RdRp and NS2B-NS3pro (IC50 of 0.8 and 7.4 µM, respectively) and LabMol-212 thermally destabilized the ZIKV NS3hel (Kd of 35 µM). Both also protected cells from death induced by ZIKV infection in in vitro cell-based assays. However, while eight compounds (including LabMol-301 and LabMol-212) showed a cytoprotective effect and prevented ZIKV-induced cell death, agreeing with our ML model for prediction of this cytoprotective effect, no compound showed a direct antiviral effect against ZIKV. Thus, the new scaffolds discovered here are promising hits for future structural optimization and for advancing the discovery of further drug candidates for ZIKV. Furthermore, this work has demonstrated the importance of the integration of computational and experimental approaches, as well as the potential of large-scale collaborative networks to advance drug discovery projects for neglected diseases and emerging viruses, despite the lack of available direct antiviral activity and cytoprotective effect data, that reflects on the assertiveness of the computational predictions. The importance of these efforts rests with the need to be prepared for future viral epidemic and pandemic outbreaks.

Asunto(s)

Antivirales , Inhibidores de Proteasas , Virus Zika , Humanos , Antivirales/farmacología , Antivirales/química , Simulación del Acoplamiento Molecular , Péptido Hidrolasas , Inhibidores de Proteasas/farmacología , Inhibidores de Proteasas/química , ARN Polimerasa Dependiente del ARN/metabolismo , Proteínas no Estructurales Virales/química , Virus Zika/efectos de los fármacos , Virus Zika/enzimología , Infección por el Virus Zika/tratamiento farmacológico

RESUMEN

We postulated that dimethyl fumarate (DMF) exerts neuroprotective effects against depression-like behaviors through astrocytes and microglia modulation. To ascertain our hypothesis and define the mechanistic pathways involved in effect of DMF on neuroinflammation, we used the depression model induced by chronic unpredictable mild stress (CUMS), in which, the mice were exposed to stressful events for 28 days and from the 14th day they received DMF in the doses of 50 and 100 mg/kg or fluoxetine 10 mg/kg or saline. On the 29th day, the animals were subjected to behavioral tests. Microglia (Iba1) and astrocyte (GFAP) marker expressions were evaluated by immunofluorescence analyzes and the cytokines TNF-α and IL-Iß by immunoenzymatic assay. In addition, computational target prediction, 3D protein structure prediction, and docking calculations were performed with monomethyl fumarate (DMF active metabolite) and the Keap1 and HCAR2 proteins, which suggested that these could be the probable targets related protective effects. CUMS induced anxiety- and depressive-like behaviors, cognitive deficit, decreased GFAP, and increased Iba1, TNF-α, and IL-Iß expression in the hippocampus. These alterations were reversed by DMF. Thus, it is suggested that one of the mechanisms involved in the antidepressant effect of DMF is neuroinflammatory suppression, through the signaling pathway HCAR2/Nrf2. However, more studies must be performed to better understand the molecular mechanisms of this drug.

Asunto(s)

Dimetilfumarato , Fármacos Neuroprotectores , Animales , Astrocitos , Depresión , Proteína 1 Asociada A ECH Tipo Kelch , Ratones , Microglía , Factor 2 Relacionado con NF-E2 , Receptores Acoplados a Proteínas G , Transducción de Señal , Factor de Necrosis Tumoral alfa

RESUMEN

Chikungunya virus (CHIKV) is the causative agent of Chikungunya fever, an acute febrile and arthritogenic illness with no effective treatments available. The development of effective therapeutic strategies could be significantly accelerated with detailed knowledge of the molecular components behind CHIKV replication. However, drug discovery is hindered by our incomplete understanding of their main components. The RNA-dependent RNA-polymerase (nsP4-CHIKV) is considered the key enzyme of the CHIKV replication complex and a suitable target for antiviral therapy. Herein, the nsP4-CHIKV was extensively characterized through experimental and computational biophysical methods. In the search for new molecules against CHIKV, a compound designated LabMol-309 was identified as a strong ligand of the nsp4-CHIKV and mapped to bind to its active site. The antiviral activity of LabMol-309 was evaluated in cellular-based assays using a CHIKV replicon system and a reporter virus. In conclusion, this study highlights the biophysical features of nsP4-CHIKV and identifies a new compound as a promising antiviral agent against CHIKV infection.

Asunto(s)

Fiebre Chikungunya , Virus Chikungunya , Antivirales/uso terapéutico , Virus Chikungunya/genética , Humanos , Ligandos , ARN/metabolismo , ARN Polimerasa Dependiente del ARN , Replicación Viral

RESUMEN

Zika virus (ZIKV) is a dangerous human pathogen and no antiviral drugs have been approved to date. The chalcones are a group of small molecules that are found in a number of different plants, including Angelica keiskei Koidzumi, also known as ashitaba. To examine chalcone anti-ZIKV activity, three chalcones, 4-hydroxyderricin (4HD), xanthoangelol (XA), and xanthoangelol-E (XA-E), were purified from a methanol-ethyl acetate extract from A. keiskei. Molecular and ensemble docking predicted that these chalcones would establish multiple interactions with residues in the catalytic and allosteric sites of ZIKV NS2B-NS3 protease, and in the allosteric site of the NS5 RNA-dependent RNA-polymerase (RdRp). Machine learning models also predicted 4HD, XA and XA-E as potential anti-ZIKV inhibitors. Enzymatic and kinetic assays confirmed chalcone inhibition of the ZIKV NS2B-NS3 protease allosteric site with IC50s from 18 to 50 µM. Activity assays also revealed that XA, but not 4HD or XA-E, inhibited the allosteric site of the RdRp, with an IC50 of 6.9 µM. Finally, we tested these chalcones for their anti-viral activity in vitro with Vero cells. 4HD and XA-E displayed anti-ZIKV activity with EC50 values of 6.6 and 22.0 µM, respectively, while XA displayed relatively weak anti-ZIKV activity with whole cells. With their simple structures and relative ease of modification, the chalcones represent attractive candidates for hit-to-lead optimization in the search of new anti-ZIKV therapeutics.

Asunto(s)

Angelica , Chalcona , Chalconas , Infección por el Virus Zika , Virus Zika , Angelica/química , Animales , Chalcona/farmacología , Chalconas/química , Chalconas/farmacología , Chlorocebus aethiops , Humanos , ARN , ARN Polimerasa Dependiente del ARN , Células Vero , Replicación Viral

RESUMEN

Although the widespread epidemic of Zika virus (ZIKV) and its neurological complications are well-known there are still no approved drugs available to treat this arboviral disease or vaccine to prevent the infection. Flavonoids from Pterogyne nitens have already demonstrated anti-flavivirus activity, although their target is unknown. In this study, we virtually screened an in-house database of 150 natural and semi-synthetic compounds against ZIKV NS2B-NS3 protease (NS2B-NS3p) using docking-based virtual screening, as part of the OpenZika project. As a result, we prioritized three flavonoids from P. nitens, quercetin, rutin and pedalitin, for experimental evaluation. We also used machine learning models, built with Assay Central® software, for predicting the activity and toxicity of these flavonoids. Biophysical and enzymatic assays generally agreed with the in silico predictions, confirming that the flavonoids inhibited ZIKV protease. The most promising hit, pedalitin, inhibited ZIKV NS2B-NS3p with an IC50 of 5 µM. In cell-based assays, pedalitin displayed significant activity at 250 and 500 µM, with slight toxicity in Vero cells. The results presented here demonstrate the potential of pedalitin as a candidate for hit-to-lead (H2L) optimization studies towards the discovery of antiviral drug candidates to treat ZIKV infections.

Asunto(s)

Antivirales/farmacología , Proteínas no Estructurales Virales/antagonistas & inhibidores , Proteínas Virales/antagonistas & inhibidores , Virus Zika/metabolismo , Animales , Antivirales/química , Supervivencia Celular/efectos de los fármacos , Chlorocebus aethiops , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Flavonas/farmacología , Aprendizaje Automático , Modelos Moleculares , Simulación del Acoplamiento Molecular , Conformación Proteica , Quercetina/farmacología , Rutina/farmacología , Serina Endopeptidasas , Células Vero

RESUMEN

The recent outbreak of coronavirus disease 2019 (COVID-19) has gained considerable attention worldwide due to its increased potential to spread and infect the general population. COVID-19 primarily targets the human respiratory epithelium but also has neuro-invasive potential. Indeed, neuropsychiatric manifestations, such as fatigue, febrile seizures, psychiatric symptoms, and delirium, are consistently observed in COVID-19. The neurobiological basis of neuropsychiatric COVID-19 symptoms is not fully understood. However, previous evidence about systemic viral infections pointed to an ongoing neuroinflammatory response to viral antigens and proinflammatory mediators/immune cells from the periphery. Microglia cells mediate the overproduction of inflammatory cytokines, free radicals, and damage signals, culminating with neurotoxic consequences. Semi-synthetic second-generation tetracyclines, including minocycline (MINO) and doxycycline (DOXY), are safe bacteriostatic agents that have remarkable neuroprotective and anti-inflammatory properties. Promising results have been obtained in clinical trials using tetracyclines for major psychiatric disorders, such as schizophrenia and major depression. Tetracyclines can inhibit microglial reactivity and neuroinflammation by inhibiting nuclear factor kappa B (NF-kB) signaling, cyclooxygenase 2, and matrix metalloproteinases (MMPs). This drug class also has a broad profile of activity against bacteria associated with community-based pneumonia, including atypical agents. COVID-19 patients are susceptible to secondary bacterial infections, especially those on invasive ventilation. Therefore, we suggest tetracyclines' repurposing as a potential treatment for COVID-19 neuropsychiatric manifestations. These drugs can represent a valuable multi-modal treatment for COVID-19-associated neuroinflammatory alterations based on their broad antimicrobial profile and neuroinflammation control.

Asunto(s)

Antiinflamatorios/administración & dosificación , Tratamiento Farmacológico de COVID-19 , Reposicionamiento de Medicamentos/métodos , Trastornos Mentales/tratamiento farmacológico , Enfermedades del Sistema Nervioso/tratamiento farmacológico , Tetraciclinas/administración & dosificación , Antivirales/administración & dosificación , COVID-19/epidemiología , COVID-19/inmunología , Humanos , Mediadores de Inflamación/antagonistas & inhibidores , Mediadores de Inflamación/inmunología , Trastornos Mentales/epidemiología , Trastornos Mentales/inmunología , Enfermedades del Sistema Nervioso/epidemiología , Enfermedades del Sistema Nervioso/inmunología

RESUMEN

Increasing reports of multidrug-resistant malaria parasites urge the discovery of new effective drugs with different chemical scaffolds. Protein kinases play a key role in many cellular processes such as signal transduction and cell division, making them interesting targets in many diseases. Protein kinase 7 (PK7) is an orphan kinase from the Plasmodium genus, essential for the sporogonic cycle of these parasites. Here, we applied a robust and integrative artificial intelligence-assisted virtual-screening (VS) approach using shape-based and machine learning models to identify new potential PK7 inhibitors with in vitro antiplasmodial activity. Eight virtual hits were experimentally evaluated, and compound LabMol-167 inhibited ookinete conversion of Plasmodium berghei and blood stages of Plasmodium falciparum at nanomolar concentrations with low cytotoxicity in mammalian cells. As PK7 does not have an essential role in the Plasmodium blood stage and our virtual screening strategy aimed for both PK7 and blood-stage inhibition, we conducted an in silico target fishing approach and propose that this compound might also inhibit P. falciparum PK5, acting as a possible dual-target inhibitor. Finally, docking studies of LabMol-167 with P. falciparum PK7 and PK5 proteins highlighted key interactions for further hit-to lead optimization.

Asunto(s)

Antimaláricos/farmacología , Inteligencia Artificial , Quinasas de Proteína Quinasa Activadas por Mitógenos/antagonistas & inhibidores , Plasmodium falciparum/efectos de los fármacos , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Protozoarias/antagonistas & inhibidores , Antimaláricos/química , Relación Dosis-Respuesta a Droga , Evaluación Preclínica de Medicamentos , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Estructura Molecular , Pruebas de Sensibilidad Parasitaria , Plasmodium falciparum/metabolismo , Inhibidores de Proteínas Quinasas/química , Proteínas Protozoarias/metabolismo , Relación Estructura-Actividad

RESUMEN

Widespread resistance against antimalarial drugs thwarts current efforts for controlling the disease and urges the discovery of new effective treatments. Drug repositioning is increasingly becoming an attractive strategy since it can reduce costs, risks, and time-to-market. Herein, we have used this strategy to identify novel antimalarial hits. We used a comparative in silico chemogenomics approach to select Plasmodium falciparum and Plasmodium vivax proteins as potential drug targets and analyzed them using a computer-assisted drug repositioning pipeline to identify approved drugs with potential antimalarial activity. Among the seven drugs identified as promising antimalarial candidates, the anthracycline epirubicin was selected for further experimental validation. Epirubicin was shown to be potent in vitro against sensitive and multidrug-resistant P. falciparum strains and P. vivax field isolates in the nanomolar range, as well as being effective against an in vivo murine model of Plasmodium yoelii Transmission-blocking activity was observed for epirubicin in vitro and in vivo Finally, using yeast-based haploinsufficiency chemical genomic profiling, we aimed to get insights into the mechanism of action of epirubicin. Beyond the target predicted in silico (a DNA gyrase in the apicoplast), functional assays suggested a GlcNac-1-P-transferase (GPT) enzyme as a potential target. Docking calculations predicted the binding mode of epirubicin with DNA gyrase and GPT proteins. Epirubicin is originally an antitumoral agent and presents associated toxicity. However, its antiplasmodial activity against not only P. falciparum but also P. vivax in different stages of the parasite life cycle supports the use of this drug as a scaffold for hit-to-lead optimization in malaria drug discovery.

Asunto(s)

Antimaláricos , Malaria Vivax , Animales , Antimaláricos/farmacología , Antimaláricos/uso terapéutico , Reposicionamiento de Medicamentos , Epirrubicina/uso terapéutico , Malaria Vivax/tratamiento farmacológico , Ratones , Plasmodium falciparum/genética , Plasmodium vivax/genética

RESUMEN

The N-methyl-(2S,4R)-trans-4-hydroxy-l-proline-enriched fraction (NMP) from Sideroxylon obtusifolium was evaluated as a neuroprotective agent in the intracerebroventricular (icv) pilocarpine (Pilo) model. To this aim, male mice were subdivided into sham (SO, vehicle), Pilo (300 µg/1 µL icv, followed by the vehicle per os, po) and NMP-treated groups (Pilo 300 µg/1 µL icv, followed by 100 or 200 mg/kg po). The treatments started one day after the Pilo injection and continued for 15 days. The effects of NMP were assessed by characterizing the preservation of cognitive function in both the Y-maze and object recognition tests. The hippocampal cell viability was evaluated by Nissl staining. Additional markers of damage were studied-the glial fibrillary acidic protein (GFAP) and the ionized calcium-binding adaptor molecule 1 (Iba-1) expression using, respectively, immunofluorescence and western blot analyses. We also performed molecular docking experiments revealing that NMP binds to the γ-aminobutyric acid (GABA) transporter 1 (GAT1). GAT1 expression in the hippocampus was also characterized. Pilo induced cognitive deficits, cell damage, increased GFAP, Iba-1, and GAT1 expression in the hippocampus. These alterations were prevented, especially by the higher NMP dose. These data highlight NMP as a promising candidate for the protection of the hippocampus, as shown by the icv Pilo model.

Asunto(s)

Hipocampo/efectos de los fármacos , Hidroxiprolina/farmacología , Fármacos Neuroprotectores/farmacología , Sapotaceae/química , Estado Epiléptico/patología , Animales , Conducta Animal/efectos de los fármacos , Proteínas de Unión al Calcio/metabolismo , Supervivencia Celular/efectos de los fármacos , Proteínas Transportadoras de GABA en la Membrana Plasmática/química , Proteínas Transportadoras de GABA en la Membrana Plasmática/metabolismo , Proteína Ácida Fibrilar de la Glía/metabolismo , Hipocampo/metabolismo , Hipocampo/patología , Humanos , Hidroxiprolina/química , Infusiones Intraventriculares , Masculino , Ratones , Proteínas de Microfilamentos/metabolismo , Simulación del Acoplamiento Molecular , Neuronas/efectos de los fármacos , Neuronas/patología , Fármacos Neuroprotectores/química , Pilocarpina/administración & dosificación , Pilocarpina/toxicidad , Plantas Medicinales/química , Estado Epiléptico/inducido químicamente

RESUMEN

Despite recent advances, current antidepressants have considerable limitations: late onset of action and the high profile of refractoriness. Biomedical research with natural products has gained growing interest in the last years, and had provide useful candidates for new antidepressants. Riparins are a group of natural alkamides obtained from Aniba riparia, which had marked neuroactive effects, mainly as antidepressant and antinociceptive agents. We made modifications of the basic structure of riparins, originating a synthetic alkamide, also known as riparin IV (RipIV). RipIV demonstrated a superior analgesic effect than its congeners and a marked antidepressant-like effect. However, the basic mechanism for the central effects of RipIV remains unknown. Here, we aimed to investigate the participation of monoaminergic neurotransmission targets in the antidepressant-like effects of RipIV. To do this, we applied a combined approach of experimental (classical pharmacology and neurochemistry) and computer-aided techniques. Our results demonstrated that RipIV presented antidepressant- and anxiolytic-like effects without modifying locomotion and motor coordination of mice. Also, RipIV increased brain monoamines and their metabolite levels. At the higher dose (100 mg/kg), RipIV increased serotonin concentrations in all studied brain areas, while at the lower one (50 mg/kg), it increased mainly dopamine and noradrenaline levels. When tested with selective receptor antagonists, RipIV antidepressant effect showed dependence of the activation of multiple targets, including D1 and D2 dopamine receptors, 5-HT2A/2, 5-HT3 receptors and α2 adrenergic receptors. Molecular docking demonstrated favorable binding conformation and affinity of RipIV to monoamine oxidase B (MAO-B), serotonin transporter (SERT), α1 receptor, D2 receptor, dopamine transporter (DAT) and at some extent GABA-A receptor. RipIV also presented a computationally predicted favorable pharmacokinetic profile. Therefore, this study demonstrated the involvement of monoaminergic targets in the mechanism of RipIV antidepressant-like action, and provide evidence of it as a promising new antidepressant.

Asunto(s)

Ansiolíticos/farmacología , Antidepresivos/farmacología , Monoaminooxidasa/efectos de los fármacos , Receptores Adrenérgicos alfa 2/efectos de los fármacos , Receptores Dopaminérgicos/efectos de los fármacos , Receptores de Serotonina/efectos de los fármacos , Tiramina/análogos & derivados , Animales , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Bupropión/farmacología , Dopamina/metabolismo , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática/efectos de los fármacos , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática/metabolismo , Fluoxetina/farmacología , Imipramina/farmacología , Ratones , Simulación del Acoplamiento Molecular , Monoaminooxidasa/metabolismo , Norepinefrina/metabolismo , Receptor de Serotonina 5-HT2A/efectos de los fármacos , Receptor de Serotonina 5-HT2A/metabolismo , Receptores Adrenérgicos alfa 2/metabolismo , Receptores Dopaminérgicos/metabolismo , Receptores de Dopamina D1 , Receptores de Dopamina D2 , Receptores de GABA-A/efectos de los fármacos , Receptores de GABA-A/metabolismo , Receptores de Serotonina/metabolismo , Receptores de Serotonina 5-HT2/efectos de los fármacos , Receptores de Serotonina 5-HT2/metabolismo , Receptores de Serotonina 5-HT3/efectos de los fármacos , Receptores de Serotonina 5-HT3/metabolismo , Serotonina/metabolismo , Proteínas de Transporte de Serotonina en la Membrana Plasmática/efectos de los fármacos , Proteínas de Transporte de Serotonina en la Membrana Plasmática/metabolismo , Tiramina/farmacología

RESUMEN

Communicated by Ramaswamy H. Sarma.

Asunto(s)

Virus del Dengue , Dengue , Infección por el Virus Zika , Virus Zika , Dengue/tratamiento farmacológico , Diseño de Fármacos , Humanos , Proteínas no Estructurales Virales/genética

RESUMEN

Zika virus (ZIKV) is a mosquito-transmitted Flavivirus, originally identified in Uganda in 1947 and recently associated with a large outbreak in South America. Despite extensive efforts there are currently no approved antiviral compounds for treatment of ZIKV infection. Here we describe the antiviral activity of diarylamines derived from anthranilic acid (FAMs) against ZIKV. A synthetic FAM (E3) demonstrated anti-ZIKV potential by reducing viral replication up to 86%. We analyzed the possible mechanisms of action of FAM E3 by evaluating the intercalation of this compound into the viral dsRNA and its interaction with the RNA polymerase of bacteriophage SP6. However, FAM E3 did not act by these mechanisms. In silico results predicted that FAM E3 might bind to the ZIKV NS3 helicase suggesting that this protein could be one possible target of this compound. To test this, the thermal stability and the ATPase activity of the ZIKV NS3 helicase domain (NS3Hel) were investigated in vitro and we demonstrated that FAM E3 could indeed bind to and stabilize NS3Hel.

Asunto(s)

Antivirales/farmacología , Replicación Viral , Virus Zika/efectos de los fármacos , ortoaminobenzoatos/farmacología , Aminas/química , Animales , Antivirales/síntesis química , Sitios de Unión , Chlorocebus aethiops , Unión Proteica , Serina Endopeptidasas/química , Serina Endopeptidasas/metabolismo , Células Vero , Proteínas Virales/química , Proteínas Virales/metabolismo , Virus Zika/fisiología , ortoaminobenzoatos/síntesis química

RESUMEN

Despite the recent outbreak of Zika virus (ZIKV), there are still no approved treatments, and early-stage compounds are probably many years away from approval. A comprehensive A-Z review of the recent advances in ZIKV drug discovery efforts is presented, highlighting drug repositioning and computationally guided compounds, including discovered viral and host cell inhibitors. Promising ZIKV molecular targets are also described and discussed, as well as targets belonging to the host cell, as new opportunities for ZIKV drug discovery. All this knowledge is not only crucial to advancing the fight against the Zika virus and other flaviviruses but also helps us prepare for the next emerging virus outbreak to which we will have to respond.

Asunto(s)

Antivirales/farmacología , Descubrimiento de Drogas , Terapia Molecular Dirigida/métodos , Infección por el Virus Zika/tratamiento farmacológico , Virus Zika/efectos de los fármacos , Antivirales/química , Antivirales/uso terapéutico , Humanos , Modelos Biológicos , Estructura Molecular

RESUMEN

Few Zika virus (ZIKV) outbreaks had been reported since its first detection in 1947, until the recent epidemics occurred in South America (2014/2015) and expeditiously became a global public health emergency. This arbovirus reached 0.5-1.3 million cases of ZIKV infection in Brazil in 2015 and rapidly spread in new geographic areas such as the Americas. Despite the mild symptoms of the Zika fever, the major concern is related to the related severe neurological disorders, especially microcephaly in newborns. Advances in ZIKV drug discovery have been made recently and constitute promising approaches to ZIKV treatment. In this review, we summarize current computational drug discovery efforts and their applicability to discovery of anti-ZIKV drugs. Lastly, we present successful examples of the use of computational approaches to ZIKV drug discovery.

Asunto(s)

Diseño Asistido por Computadora/estadística & datos numéricos , Descubrimiento de Drogas/instrumentación , Virus Zika , Antivirales/farmacología , Triaje/métodos , Metodologías Computacionales , Flavivirus

RESUMEN

America is still suffering with the outbreak of Zika virus (ZIKV) infection. Congenital ZIKV syndrome has already caused a public health emergency of international concern. However, there are still no vaccines to prevent or drugs to treat the infection caused by ZIKV. The ZIKV NS3 helicase (NS3h) protein is a promising target for drug discovery due to its essential role in viral genome replication. NS3h unwinds the viral RNA to enable the replication of the viral genome by the NS5 protein. NS3h contains two important binding sites: the NTPase binding site and the RNA binding site. Here, we used molecular dynamics (MD) simulations to study the molecular behavior of ZIKV NS3h in the presence and absence of ssRNA and the potential implications for NS3h activity and inhibition. Although there is conformational variability and poor electron densities of the RNA binding loop in various apo flaviviruses NS3h crystallographic structures, the MD trajectories of NS3h-ssRNA demonstrated that the RNA binding loop becomes more stable when NS3h is occupied by RNA. Our results suggest that the presence of RNA generates important interactions with the RNA binding loop, and these interactions stabilize the loop sufficiently that it remains in a closed conformation. This closed conformation likely keeps the ssRNA bound to the protein for a sufficient duration to enable the unwinding/replication activities of NS3h to occur. In addition, conformational changes of this RNA binding loop can change the nature and location of the optimal ligand binding site, according to ligand binding site prediction results. These are important findings to help guide the design and discovery of new inhibitors of NS3h as promising compounds to treat the ZIKV infection.

Asunto(s)

Modelos Químicos , Simulación de Dinámica Molecular , ARN Viral/química , ARN Viral/ultraestructura , Proteínas no Estructurales Virales/química , Proteínas no Estructurales Virales/ultraestructura , Virus Zika/enzimología , Sitios de Unión , Activación Enzimática , Conformación de Ácido Nucleico , Unión Proteica , Conformación Proteica , ARN Helicasas/química , ARN Helicasas/ultraestructura , Serina Endopeptidasas/química , Serina Endopeptidasas/ultraestructura

RESUMEN

The peroxisome proliferator-activated receptor γ (PPARγ) ligands are important therapeutic drugs for the treatment of type 2 diabetes, obesity and cardiovascular diseases. In particular, partial agonists and non-agonists are interesting targets to reduce glucose levels, presenting few side effects in comparison to full agonists. In this work, we present a set of CHARMM-based parameters of a molecular mechanics force field for two PPARγ ligands, GQ16 and SR1664. GQ16 belongs to the thiazolidinedione class of drugs and it is a PPARγ partial agonist that has been shown to promote the "browning" of white adipose tissue. SR1664 is the precursor of the PPARγ non-agonist class of ligands that activates PPARγ in a non-classical manner. Here, we use quantum chemical calculations consistent with the CHARMM protocol to obtain bonded and non-bonded parameters, including partial atomic charges and effective torsion potentials for both molecules. The newly parameterized models were evaluated by examining the behavior of GQ16 and SR1664 free in water and bound to the ligand binding pocket of PPARγ using molecular dynamics simulations. The potential parameters derived here are readily transferable to a variety of pharmaceutical compounds and similar PPARγ ligands.

Asunto(s)

Algoritmos , Compuestos de Bifenilo/farmacología , Simulación del Acoplamiento Molecular , PPAR gamma/química , Tiazolidinedionas/farmacología , Sitios de Unión , Compuestos de Bifenilo/química , Ligandos , PPAR gamma/metabolismo , Unión Proteica , Tiazolidinedionas/química