RESUMO
Dengue virus (DENV) infection is known to affect host cell metabolism, but the molecular players involved are still poorly known. Using a proteomics approach, we identified six DENV proteins associated with mitochondria isolated from infected hepatocytes, and most of the peptides identified were from NS3. We also found an at least twofold decrease of several electron transport system (ETS) host proteins. Thus, we investigated whether NS3 could modulate the ETS function by incubating recombinant DENV NS3 constructs in mitochondria isolated from mouse liver. We found that NS3pro (NS3 protease domain), but not the correspondent catalytically inactive mutant (NS3proS135A), impairs complex I (CI)-dependent NADH:ubiquinone oxidoreductase activity, but not the activities of complexes II, III, IV, or V. Accordingly, using high-resolution respirometry, we found that both NS3pro and full-length NS3 decrease the respiratory rates associated with malate/pyruvate oxidation in mitochondria. The NS3-induced impairment in mitochondrial respiration occurs without altering either leak respiration or mitochondria's capacity to maintain membrane potential, suggesting that NS3 does not deeply affect mitochondrial integrity. Remarkably, CI activity is also inhibited in DENV-infected cells, supporting that the NS3 effects observed in isolated mitochondria may be relevant in the context of the infection. Finally, in silico analyses revealed the presence of potential NS3 cleavage sites in 17 subunits of mouse CI and 16 subunits of human CI, most of them located on the CI surface, suggesting that CI is prone to undergo proteolysis by NS3. Our findings suggest that DENV NS3 can modulate mitochondrial bioenergetics by directly affecting CI function. IMPORTANCE: Dengue virus (DENV) infection is a major public health problem worldwide, affecting about 400 million people yearly. Despite its importance, many molecular aspects of dengue pathogenesis remain poorly known. For several years, our group has been investigating DENV-induced metabolic alterations in the host cells, focusing on the bioenergetics of mitochondrial respiration. The results of the present study reveal that the DENV non-structural protein 3 (NS3) is found in the mitochondria of infected cells, impairing mitochondrial respiration by directly targeting one of the components of the electron transport system, the respiratory complex I (CI). NS3 acts as the viral protease during the DENV replication cycle, and its proteolytic activity seems necessary for inhibiting CI function. Our findings uncover new nuances of DENV-induced metabolic alterations, highlighting NS3 as an important player in the modulation of mitochondria function during infection.
Assuntos
Vírus da Dengue , Complexo I de Transporte de Elétrons , Mitocôndrias , Proteínas não Estruturais Virais , Proteínas não Estruturais Virais/metabolismo , Proteínas não Estruturais Virais/genética , Animais , Vírus da Dengue/fisiologia , Vírus da Dengue/genética , Camundongos , Complexo I de Transporte de Elétrons/metabolismo , Complexo I de Transporte de Elétrons/genética , Humanos , Mitocôndrias/metabolismo , Hepatócitos/virologia , Hepatócitos/metabolismo , Serina Endopeptidases/metabolismo , Serina Endopeptidases/genética , Dengue/virologia , Dengue/metabolismo , Respiração Celular , Proteômica , Proteases ViraisRESUMO
Previous studies have demonstrated the relevance of several soluble molecules in the pathogenesis of dengue. In this regard, a possible role for angiotensin II (Ang II) in the pathophysiology of dengue has been suggested by the observation of a blockade of Ang II in patients with dengue, increased expression of molecules related to Ang II production in the plasma of dengue patients, increased expression of circulating cytokines and soluble molecules related to the action of Ang II, and an apparent relationship between DENV, Ang II effects, and miRNAs. In addition, in ex vivo experiments, the blockade of Ang II AT1 receptor and ACE-1 (angiotensin converting enzyme 1), both of which are involved in Ang II production and its function, inhibits infection of macrophages by DENV, suggesting a role of Ang II in viral entry or in intracellular viral replication of the virus. Here, we discuss the possible mechanisms of Ang II in the entry and replication of DENV. Ang II has the functions of increasing the expression of DENV entry receptors, creation of clathrin-coated vesicles, and increasing phagocytosis, all of which are involved in DENV entry. This hormone also modulates the expression of the Rab5 and Rab7 proteins, which are important in the endosomal processing of DENV during viral replication. This review summarizes the data related to the possible involvement of Ang II in the entry of DENV into cells and its replication.
Assuntos
Angiotensina II , Vírus da Dengue , Internalização do Vírus , Replicação Viral , Angiotensina II/metabolismo , Humanos , Vírus da Dengue/fisiologia , Vírus da Dengue/genética , Animais , Dengue/virologia , Dengue/metabolismoRESUMO
Dengue is an acute febrile illness caused by the Dengue virus (DENV), with a high number of cases worldwide. There is no available treatment that directly affects the virus or the viral cycle. The objective of this study was to identify a compound derived from natural products that interacts with the NS5 protein of the dengue virus through virtual screening and evaluate its in vitro antiviral effect on DENV-2. Molecular docking was performed on NS5 using AutoDock Vina software, and compounds with physicochemical and pharmacological properties of interest were selected. The preliminary antiviral effect was evaluated by the expression of the NS1 protein. The effect on viral genome replication and/or translation was determined by NS5 production using DENV-2 Huh-7 replicon through ELISA and viral RNA quantification using RT-qPCR. The in silico strategy proved effective in finding a compound (M78) with an indole-like structure and with an effect on the replication cycle of DENV-2. Treatment at 50 µM reduced the expression of the NS5 protein by 70% and decreased viral RNA by 1.7 times. M78 is involved in the replication and/or translation of the viral genome.
Assuntos
Produtos Biológicos , Vírus da Dengue , Dengue , Humanos , Antivirais/química , Vírus da Dengue/genética , Simulação de Acoplamento Molecular , Produtos Biológicos/farmacologia , RNA Viral/genética , Proteínas não Estruturais Virais/genética , Dengue/metabolismo , Replicação ViralRESUMO
Transcriptomics, proteomics and pathogen-host interactomics data are being explored for the in silico-informed selection of drugs, prior to their functional evaluation. The effectiveness of this kind of strategy has been put to the test in the current COVID-19 pandemic, and it has been paying off, leading to a few drugs being rapidly repurposed as treatment against SARS-CoV-2 infection. Several neglected tropical diseases, for which treatment remains unavailable, would benefit from informed in silico investigations of drugs, as performed in this work for Dengue fever disease. We analyzed transcriptomic data in the key tissues of liver, spleen and blood profiles and verified that despite transcriptomic differences due to tissue specialization, the common mechanisms of action, "Adrenergic receptor antagonist", "ATPase inhibitor", "NF-kB pathway inhibitor" and "Serotonin receptor antagonist", were identified as druggable (e.g., oxprenolol, digoxin, auranofin and palonosetron, respectively) to oppose the effects of severe Dengue infection in these tissues. These are good candidates for future functional evaluation and clinical trials.
Assuntos
Antivirais/uso terapêutico , Dengue/tratamento farmacológico , Transcriptoma , Adenosina Trifosfatases/antagonistas & inibidores , Antagonistas Adrenérgicos/farmacologia , Antagonistas Adrenérgicos/uso terapêutico , Antivirais/farmacologia , Encéfalo/metabolismo , Simulação por Computador , Dengue/sangue , Dengue/genética , Dengue/metabolismo , Descoberta de Drogas , Avaliação Pré-Clínica de Medicamentos , Reposicionamento de Medicamentos , Humanos , Fígado/metabolismo , Redes e Vias Metabólicas/efeitos dos fármacos , NF-kappa B/metabolismo , Antagonistas da Serotonina/farmacologia , Antagonistas da Serotonina/uso terapêutico , Dengue Grave/sangue , Dengue Grave/tratamento farmacológico , Dengue Grave/genética , Dengue Grave/metabolismo , Baço/metabolismoRESUMO
BACKGROUND: Dengue virus causes dengue fever (DF)disease, transmitted by the mosquito Aedes aegypti. The symptoms could be severe and disable the affected individuals for weeks. The severe form, dengue hemorrhagic fever (DHF), can lead to death if not adequately attended to. Due to global warming, the vector mosquito will advance over new areas and expose more people to this disease over the next decades. Despite the severity, there are no treatments nor efficient vaccines available. Metabolomic studies have shown a new perspective to understand this disease better at a new molecular level. AIM OF REVIEW: Many published works rely on samples obtained from animal studies. This review will mainly focus on human samples and cell culture experiments to view how the dengue virus affects the metabolomic profile. KEY SCIENTIFIC CONCEPTS OF REVIEW: The review compiles the sample sources, metabolomic techniques used, the detected compounds, and how they behave in different DF stages. This disease causes a significant change in many metabolites, but some results are still conflicting between studies. The results gathered here show that metabolomic approaches prove to be an excellent and viable way to expand knowledge about DF.
Assuntos
Dengue/metabolismo , Metabolômica/métodos , Aedes , Aminoácidos/metabolismo , Animais , Metabolismo dos Carboidratos , Dengue/virologia , Humanos , Metabolismo dos Lipídeos , Mosquitos VetoresRESUMO
The aims of this study were to determine the involvement of interleukin 17 (IL-17) and IL-17-producing cells in dengue pathogenesis. Blood samples from dengue virus (DENV)-infected patients were collected on different days after the onset of symptoms. Patients were classified according to 1997 World Health Organization guidelines. Our study examined 152 blood samples from dengue fever (DF, n = 109) and dengue hemorrhagic fever (DHF, n = 43) patients and 90 blood samples from healthy controls (HC). High serum concentrations of IL-17A and IL-22 were also associated with DHF (IL-17A [DHF vs. DF, p < 0.01; DHF vs. HC, p < 0.0001]; IL-22 [DHF vs. DF, p < 0.05; DHF vs. HC, p < 0.0001]). Moreover, there was a positive correlation between serum levels of IL-17A and IL-23, a key cytokine that promotes IL-17-based immune responses (r = 0.4089, p < 0.0001). Consistent with the IL-17-biased immune response in DHF patients, we performed ex vivo activation of peripheral blood mononuclear cells (PBMCs) from DHF patients and flow cytometry analysis showed a robust IL-17-biased immune response, characterized by a high frequency of CD4+IL-17+ producing cells. Our results suggests IL-17-producing cells and their related cytokines can play a prominent role in this viral disease.
Assuntos
Linfócitos T CD4-Positivos/metabolismo , Vírus da Dengue/fisiologia , Dengue/etiologia , Dengue/metabolismo , Interleucina-17/metabolismo , Células Th17/metabolismo , Adolescente , Adulto , Idoso , Linfócitos T CD4-Positivos/imunologia , Criança , Citocinas/sangue , Citocinas/metabolismo , Dengue/diagnóstico , Suscetibilidade a Doenças , Feminino , Humanos , Interleucina-17/sangue , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Células Th17/imunologia , Adulto JovemRESUMO
The arthropod-borne flaviviruses are important human pathogens, and a deeper understanding of the virus-host cell interaction is required to identify cellular targets that can be used as therapeutic candidates. It is well reported that the flaviviruses hijack several cellular functions, such as exosome-mediated cell communication during infection, which is modulated by the delivery of the exosomal cargo of pro- or antiviral molecules to the receiving host cells. Therefore, to study the role of exosomes during flavivirus infections is essential, not only to understand its relevance in virus-host interaction, but also to identify molecular factors that may contribute to the development of new strategies to block these viral infections. This review explores the implications of exosomes in flavivirus dissemination and transmission from the vector to human host cells, as well as their involvement in the host immune response. The hypothesis about exosomes as a transplacental infection route of ZIKV and the paradox effect or the dual role of exosomes released during flavivirus infection are also discussed here. Although several studies have been performed in order to identify and characterize cellular and viral molecules released in exosomes, it is not clear how all of these components participate in viral pathogenesis. Further studies will determine the balance between protective and harmful exosomes secreted by flavivirus infected cells, the characteristics and components that distinguish them both, and how they could be a factor that determines the infection outcome.
Assuntos
Comunicação Celular , Exossomos/metabolismo , Infecções por Flavivirus/metabolismo , Flavivirus/metabolismo , Interações Hospedeiro-Patógeno , Animais , Vetores Aracnídeos/virologia , Dengue/metabolismo , Vesículas Extracelulares/metabolismo , Vesículas Extracelulares/virologia , Infecções por Flavivirus/transmissão , Humanos , Mosquitos Vetores/virologia , Carrapatos/virologia , Infecção por Zika virus/metabolismoRESUMO
During flavivirus infection, some viral proteins move to the nucleus and cellular components are relocated from the nucleus to the cytoplasm. Thus, the integrity of the main regulator of the nuclear-cytoplasmic transport, the nuclear pore complex (NPC), was evaluated during infection with dengue virus (DENV) and Zika virus (ZIKV). We found that while during DENV infection the integrity and distribution of at least three nucleoporins (Nup), Nup153, Nup98, and Nup62 were altered, during ZIKV infection, the integrity of TPR, Nup153, and Nup98 were modified. In this work, several lines of evidence indicate that the viral serine protease NS2B3 is involved in Nups cleavage. First, the serine protease inhibitors, TLCK and Leupeptin, prevented Nup98 and Nup62 cleavage. Second, the transfection of DENV and ZIKV NS2B3 protease was sufficient to inhibit the nuclear ring recognition detected in mock-infected cells with the Mab414 antibody. Third, the mutant but not the active (WT) protease was unable to cleave Nups in transfected cells. Thus, here we describe for the first time that the NS3 protein from flavivirus plays novel functions hijacking the nuclear pore complex, the main controller of the nuclear-cytoplasmic transport.
Assuntos
Vírus da Dengue/metabolismo , Poro Nuclear/metabolismo , Serina Endopeptidases/metabolismo , Proteínas Virais/metabolismo , Zika virus/metabolismo , Transporte Ativo do Núcleo Celular , Dengue/metabolismo , Dengue/virologia , Vírus da Dengue/ultraestrutura , Immunoblotting , Microscopia Confocal , Microscopia Eletrônica de Transmissão , Membrana Nuclear/metabolismo , Complexo de Proteínas Formadoras de Poros Nucleares/metabolismo , Zika virus/ultraestrutura , Infecção por Zika virus/metabolismo , Infecção por Zika virus/virologiaRESUMO
Patients infected with the Dengue virus (DENV) often present with a massive generation of DENV-specific antibody-secreting cells (ASCs) in the blood. In some cases, these ASCs represent more than 50% of the circulating B cells, a higher magnitude than those induced by other infections, vaccinations, and plasma cell lymphomas. However, it remains unclear how the DENV infection elicits this colossal response. To address this issue, we utilised an in vitro strategy to induce human PBMCs of healthy individuals incubated with DENV particles (DENV4 TVP/360) to differentiate into ASCs. As controls, PBMCs were incubated with a mitogen cocktail or supernatants of uninfected C6/36 cells (mock). The ASC phenotype and function were increasingly detected in the DENV and mitogen-cultured PBMCs as compared to mock-treated cells. In contrast to the in vivo condition, secreted IgG derived from the PBMC-DENV culture was not DENV-specific. Lower ASC numbers were observed when inactivated viral particles or purified B cells were added to the cultures. The physical contact was essential between B cells and the remaining PBMCs for the DENV-mediated ASC response. Considering the evidence for the activation of the tryptophan metabolism detected in the serum of Dengue patients, we assessed its relevance in the DENV-mediated ASC differentiation. For this, tryptophan and its respective metabolites were quantified in the supernatants of cell cultures through mass spectrophotometry. Tryptophan depletion and kynurenine accumulation were found in the supernatants of PBMC-DENV cultures, which presented enhanced detection of indoleamine 2,3-dioxygenase 1 and 2 transcripts as compared to controls. In PBMC-DENV cultures, tryptophan and kynurenine levels strongly correlated to the respective ASC numbers, while the kynurenine levels were directly proportional to the secreted IgG titers. Contrastingly, PBMCs incubated with Zika or attenuated Yellow Fever viruses showed no correlation between their kynurenine concentrations and ASC numbers. Therefore, our data revealed the existence of distinct pathways for the DENV-mediated ASC differentiation and suggest the involvement of the tryptophan metabolism in this cellular process triggered by flavivirus infections.
Assuntos
Linfócitos B/imunologia , Linfócitos B/virologia , Diferenciação Celular/imunologia , Vírus da Dengue/imunologia , Dengue/metabolismo , Triptofano/metabolismo , Febre Amarela/metabolismo , Vírus da Febre Amarela/imunologia , Infecção por Zika virus/metabolismo , Zika virus/imunologia , Doadores de Sangue , Células Cultivadas , Dengue/imunologia , Dengue/virologia , Humanos , Cinurenina/metabolismo , Febre Amarela/imunologia , Febre Amarela/virologia , Infecção por Zika virus/imunologia , Infecção por Zika virus/virologiaRESUMO
Dengue virus (DENV) threatens almost 70% of the world's population, with no therapeutic currently available. The severe, potentially lethal forms of DENV disease (dengue hemorrhagic fever/dengue shock syndrome) are associated with the production of high level of cytokines, elicited as part of the host antiviral response, although the molecular mechanisms have not been fully elucidated. We previously showed that infection by DENV serotype 2 (DENV2) disrupts promyelocytic leukemia (PML) gene product nuclear bodies (PML-NBs) after viral protein translation in infected cells. Apart from playing a key role as the nucleating agent in forming PML-NBs, PML has antiviral activity against various viruses, including DENV. The present study builds on this work, showing for the first time that all four DENV serotypes elicit PML-NB breakdown. Importantly, we show for the first time that of the nuclear localizing proteins of DENV, DENV non-structural protein (NS) 5 polymerase alone is sufficient to elicit PML-NB disassembly, in part through complexing with PML isoforms III and IV, but not other PML isoforms or other PML-NB components. The results raise the possibility that PML-NB disruption by nuclear localized NS5 contributes to DENV's suppression of the host antiviral response.