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Viral infection induces production of type I interferons and expression of interferon-stimulated genes (ISGs) that play key roles in inhibiting viral infection. Here, we show that the ISG guanylate-binding protein 5 (GBP5) inhibits N-linked glycosylation of key proteins in multiple viruses, including SARS-CoV-2 spike protein. GBP5 binds to accessory subunits of the host oligosaccharyltransferase (OST) complex and blocks its interaction with the spike protein, which results in misfolding and retention of spike protein in the endoplasmic reticulum likely due to decreased N-glycan transfer, and reduces the assembly and release of infectious virions. Consistent with these observations, pharmacological inhibition of the OST complex with NGI-1 potently inhibits glycosylation of other viral proteins, including MERS-CoV spike protein, HIV-1 gp160, and IAV hemagglutinin, and prevents the production of infectious virions. Our results identify a novel strategy by which ISGs restrict virus infection and provide a rationale for targeting glycosylation as a broad antiviral therapeutic strategy.
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To address the need for multivalent vaccines against Coronaviridae that can be rapidly developed and manufactured, we compared antibody responses against SARS-CoV, SARS-CoV-2, and several variants of concern in mice immunized with mRNA-lipid nanoparticle vaccines encoding homodimers or heterodimers of SARS-CoV/SARS-CoV-2 receptor-binding domains. All vaccine constructs induced robust anti-RBD antibody responses, and the heterodimeric vaccine elicited an IgG response capable of cross-neutralizing SARS-CoV, SARS-CoV-2 Wuhan-Hu-1, B.1.351 (beta), and B.1.617.2 (delta) variants.
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COVID-19 , SARS-CoV-2 , Animais , Camundongos , Humanos , SARS-CoV-2/genética , Vacinas Combinadas , Anticorpos Neutralizantes , Nanovacinas , Glicoproteína da Espícula de Coronavírus/genética , COVID-19/prevenção & controle , RNA Mensageiro/genética , Vacinas de mRNA , Lipídeos , Anticorpos AntiviraisRESUMO
The lack of physiologically relevant in vitro models has hampered progress in understanding human lung development and disease. Here, we describe a protocol in which human induced pluripotent stem cells (hiPSCs) undergo stepwise differentiation into definitive endoderm (>88% population) to three-dimensional (3D) lung organoids (LORGs), which contain both epithelial and mesenchymal cellular architecture and display proximal and distal airway patterning. These LORGs can maintained for more than 90 days by re-embedding in the Matrigel. We show the utility of LORGs for disease modeling and drug screening by infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and treatment with antiviral drugs.
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BACKGROUND: The fixation of inferior pole fractures of the patella (IPFPs) is still a great challenge for surgeons. MATERIALS AND METHODS: We introduced a new fixation method for IPFP fixation, that is, separate vertical wiring plus bilateral anchor girdle suturing fixation (SVW-BSAG). Three finite element models including the anterior tension band wiring (ATBW) model, separate vertical wiring (SVW) model and SVW-BSAG model, were built to evaluate the fixation strength of different fixation methods. A total of 41 consecutive patients with IPFP injury were enrolled in this retrospective study, including 23 patients in the ATBW group and 18 patients in the SVW-BSAG group. The operation time, radiation exposure, full weight-bearing time, Bostman score, extension lag versus contralateral healthy leg, Insall-Salvati ratio, and radiograph outcomes were employed to assess and compare the ATBW group and SVW-BSAG group. RESULTS: The finite element analysis confirmed that the SVW-BSAG fixation method was as reliable as the ATBW fixation method in terms of fixed strength. Through retrospective analysis, we found that there was no significant difference between the SVW-BSAG and ATBW groups in age, sex, BMI, fracture side, fracture type, or follow-up time. There were no significant differences between the two groups in the Insall-Salvati ratio, 6-month Bostman score, and fixation failure. Compared with the ATBW group, the SVW-BSAG group showed advantages in intraoperative radiation exposure, full weight-bearing time, and extension lag versus the contralateral healthy leg. CONCLUSION: The finite element analysis and clinical results showed that SVW-BSAG fixation methods are a reliable and valuable for IPFP treatment.
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Fraturas Ósseas , Traumatismos do Joelho , Humanos , Estudos Retrospectivos , Patela/diagnóstico por imagem , Patela/cirurgia , Patela/lesões , Fios Ortopédicos , Fraturas Ósseas/diagnóstico por imagem , Fraturas Ósseas/cirurgia , Fixação Interna de Fraturas/métodosRESUMO
Noise annoyance is recognized as an expression of physiological and psychological strain in acoustical environment. The studies on prediction of noise annoyance and parametric sensitivity analysis of factors affecting it have been rarely reported in India. A hybrid ConvLSTM technique was developed in the study to predict traffic-induced noise annoyance in 484 people based on ambient noise levels, as well as survey information. Ambient noise levels were obtained at different locations of Dhanbad city using sound level meter at varying intervals, viz. 09AM-12PM, 03PM-06PM, and 08PM-11PM. The proposed method was compared with some well-known neural network techniques such as K-nearest neighbors (KNN), artificial neural network (ANN), recurrent neural network (RNN), and long-short-term memory (LSTM). The experimental results indicate that the proposed method outperforms other techniques and can be a reliable approach for prediction of noise annoyance with an accuracy of 93.8%. It can be concluded from noise maps that the noise levels in all locations of the Dhanbad city were higher than 70 dB(A) and noise sensitivity is the most important input variable of traffic-induced noise annoyance, followed by honking noise, education, exposure hours, LAeq, sleeping disorder, and chronic disease. The study shall facilitate in developing a decision support tool for prediction of noise annoyance and promoting implementation of suitable public policy in urban cities.
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Ruído dos Transportes , Humanos , Exposição Ambiental , Cidades , Inquéritos e Questionários , AcústicaRESUMO
To address the need for multivalent vaccines against Coronaviridae that can be rapidly developed and manufactured, we compared antibody responses against SARS-CoV, SARS-CoV-2, and several variants of concern in mice immunized with mRNA-lipid nanoparticle vaccines encoding homodimers or heterodimers of SARS-CoV/SARS-CoV-2 receptor-binding domains. All vaccine constructs induced robust anti-viral antibody responses, and the heterodimeric vaccine elicited an IgG response capable of cross-neutralizing SARS-CoV, SARS-CoV-2 Wuhan-Hu-1, B.1.351 (beta), and B.1.617.2 (delta) variants.
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To combat the problem of acaricide resistance in ticks, efforts have been made to develop eco-friendly herbal acaricides which are safe for animal use with no possibilities of evoking environment and residual toxicity. In the present study, the acaricidal properties of a commonly available plant, Annona squamosa have been established to develop a novel antitick phytoformulation using leaf extract, suitable solvents and emulsifier for managing resistant tick infestations in animals. The quality control of the safe and stable phytoformulation using Rutin as a major constituent was maintained by HPTLC profiling. Several phytformulations (A-E) were prepared and formulation 'C' is identifried as the most effective showing 52.5-75% antitick activity against in vitro treated resistant strains of R. microplus (IVRI-IV and V) with 33.8-40.2% inhibition of oviposition while 65-85% mortality against multiacaricide resistant field populations. The phytoformulation provided 70.4% efficacy after first larval challenge in experimentally infested animals. The field efficacy of the formulation in different multilocational field trials was 68.53-77.8%. The detail antitick efficacy of the formulation along with safety and stability are explained as a component of antitck technology to manage resistant tick problem in livestock.
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Acaricidas , Annona , Doenças dos Bovinos , Extratos Vegetais , Rhipicephalus , Infestações por Carrapato , Acaricidas/farmacologia , Animais , Annona/química , Bovinos , Resistência a Medicamentos , Feminino , Larva , Extratos Vegetais/farmacologia , Infestações por Carrapato/tratamento farmacológico , Infestações por Carrapato/veterináriaRESUMO
The emergence of a new coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), presents an urgent public health crisis. Without available targeted therapies, treatment options remain limited for COVID-19 patients. Using medicinal chemistry and rational drug design strategies, we identify a 2-phenyl-1,2-benzoselenazol-3-one class of compounds targeting the SARS-CoV-2 main protease (Mpro). FRET-based screening against recombinant SARS-CoV-2 Mpro identified six compounds that inhibit proteolysis with nanomolar IC50 values. Preincubation dilution experiments and molecular docking determined that the inhibition of SARS-CoV-2 Mpro can occur by either covalent or noncovalent mechanisms, and lead E04 was determined to inhibit Mpro competitively. Lead E24 inhibited viral replication with a nanomolar EC50 value (844 nM) in SARS-CoV-2-infected Vero E6 cells and was further confirmed to impair SARS-CoV-2 replication in human lung epithelial cells and human-induced pluripotent stem cell-derived 3D lung organoids. Altogether, these studies provide a structural framework and mechanism of Mpro inhibition that should facilitate the design of future COVID-19 treatments.
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Antivirais/farmacologia , Benzotiazóis/farmacologia , Proteases 3C de Coronavírus/antagonistas & inibidores , Inibidores de Cisteína Proteinase/farmacologia , Descoberta de Drogas , SARS-CoV-2/efeitos dos fármacos , Animais , Antivirais/síntese química , Antivirais/química , Benzotiazóis/química , COVID-19/metabolismo , Chlorocebus aethiops , Proteases 3C de Coronavírus/isolamento & purificação , Proteases 3C de Coronavírus/metabolismo , Cristalografia por Raios X , Inibidores de Cisteína Proteinase/síntese química , Inibidores de Cisteína Proteinase/química , Relação Dose-Resposta a Droga , Transferência Ressonante de Energia de Fluorescência , Humanos , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Estrutura Molecular , SARS-CoV-2/enzimologia , Células Vero , Replicação Viral/efeitos dos fármacos , Tratamento Farmacológico da COVID-19RESUMO
Sickle cell disease is a major public health problem in India. Lack of rapid and reliable diagnostic methods result in many avoidable deaths in affected population. Current diagnostic tools are laboratory based, expensive and need trained manpower. Here, we evaluated the performance of a microchip-based cellulose acetate electrophoresis test, "Gazelle" in the tribal-dominated Indian states of Chhattisgarh and Madhya Pradesh. A total of 1,050 patients were screened by sickle cell solubility, hemoglobin (cellulose acetate) electrophoresis, high-performance liquid chromatography (HPLC) and Gazelle. Of the total 1,027 test results obtained, 960 tests were "Valid" (93.5%) and included in the analysis. Gazelle identified all patients with disease (HbSS and Thalassemia Major) with 100% accuracy. Gazelle demonstrated 100% sensitivity when comparing sickle cell disease (SCD) vs. sickle cell trait and SCD vs. normal. Specificity was 98.9% and 99.5% when comparing SCD vs. trait and trait vs. normal, respectively. Specificity was 99.8% when comparing SCD vs. normal and sensitivity was 99.3% when comparing trait vs. normal. Overall, Gazelle yielded a high accuracy (99.0%) compared to reference standard tests (hemoglobin electrophoresis and HPLC). Gazelle is a low-cost, rapid diagnostic test with high accuracy for detecting SCD both quantitatively and qualitatively. Gazelle can be a potential screening tool for the rapid diagnosis in resource limited settings and developing countries with high burden of hemoglobin disorders.
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Osteoarthritis (OA) is a progressive degenerative joint disease whose molecular mechanism has not been revealed clearly, and there is still no effective approach to cure OA completely. Recently, reactive oxygen species (ROS) are exposed as an important mediator of OA's inflammatory response, and it has been regarded as a therapeutic target for OA treatment. MnO2 nanoparticles possess good biocompatibility and can act as an artificial nanoenzyme to scavenge ROS in various diseases effectively. In this study, the modified Stöber method was applied to synthesize hollow MnO2 (H-MnO2) and H-MnO2 was modified with NH2-PEG-NH2, which possesses excellent biological stability and biocompatibility. It induced a change in the articular cartilage structure changes in vivo, with the knee tissue staining and micro-CT scanning of the whole knee suggesting that H-MnO2 nanoparticles could effectively remove ROS and significantly relieve the inflammatory response of OA without obvious side effects. This study reveals the therapeutic effects of MnO2-based nanomedicine toward OA, which provides potential alternative therapeutic options for patients with inflammation tissue.
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Nanopartículas , Osteoartrite , Condrócitos , Humanos , Compostos de Manganês , Osteoartrite/tratamento farmacológico , Óxidos , Espécies Reativas de OxigênioRESUMO
National Capital Region (NCR) encompassing New Delhi is one of the most polluted urban metropolitan areas in the world. Real-time chemical characterization of fine particulate matter (PM1 and PM2.5) was carried out using three aerosol mass spectrometers, two aethalometers, and one single particle soot photometer (SP2) at two sites in Delhi (urban) and one site located ~40 km downwind of Delhi, during January-March 2018. The campaign mean PM2.5 (NR-PM2.5 + BC) concentrations at the two urban sites were 153.8 ± 109.4 µg.m-3 and 127.8 ± 83.2 µg.m-3, respectively, whereas PM1 (NR-PM1 + BC) was 72.3 ± 44.0 µg.m-3 at the downwind site. PM2.5 particles were composed mostly of organics (43-44)% followed by chloride (14-17)%, ammonium (9-11)%, nitrate (9%), sulfate (8-10)%, and black carbon (11-16)%, whereas PM1 particles were composed of 47% organics, 13% sulfate as well as ammonium, 11% nitrate as well as chloride, and 5% black carbon. Organic aerosol (OA) source apportionment was done using positive matrix factorization (PMF), solved using an advanced multi-linear engine (ME-2) model. Highly mass-resolved OA mass spectra at one urban and downwind site were factorized into three primary organic aerosol (POA) factors including one traffic-related and two solid-fuel combustion (SFC), and three oxidized OA (OOA) factors. Whereas unit mass resolution OA at the other urban site was factorized into two POA factors related to traffic and SFC, and one OOA factor. OOA constituted a majority of the total OA mass (45-55)% with maximum contribution during afternoon hours ~(70-80)%. Significant differences in the absolute OOA concentration between the two urban sites indicated the influence of local emissions on the oxidized OA formation. Similar PM chemical composition, diurnal and temporal variations at the three sites suggest similar type of sources affecting the particulate pollution in Delhi and adjoining cities, but variability in mass concentration suggest more local influence than regional.
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COVID-19 is a transmissible respiratory disease caused by a novel coronavirus, SARS-CoV-2, and has become a global health emergency. There is an urgent need for robust and practical in vitro model systems to investigate viral pathogenesis. Here, we generated human induced pluripotent stem cell (iPSC)-derived lung organoids (LORGs), cerebral organoids (CORGs), neural progenitor cells (NPCs), neurons, and astrocytes. LORGs containing epithelial cells, alveolar types 1 and 2, highly express ACE2 and TMPRSS2 and are permissive to SARS-CoV-2 infection. SARS-CoV-2 infection induces interferons, cytokines, and chemokines and activates critical inflammasome pathway genes. Spike protein inhibitor, EK1 peptide, and TMPRSS2 inhibitors (camostat/nafamostat) block viral entry in LORGs. Conversely, CORGs, NPCs, astrocytes, and neurons express low levels of ACE2 and TMPRSS2 and correspondingly are not highly permissive to SARS-CoV-2 infection. Infection in neuronal cells activates TLR3/7, OAS2, complement system, and apoptotic genes. These findings will aid in understanding COVID-19 pathogenesis and facilitate drug discovery.
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Encéfalo/virologia , COVID-19/virologia , Células-Tronco Pluripotentes Induzidas/virologia , Pulmão/virologia , Células-Tronco Neurais/virologia , Organoides/virologia , SARS-CoV-2/patogenicidade , Apoptose/fisiologia , Encéfalo/metabolismo , COVID-19/metabolismo , Células Cultivadas , Proteínas do Sistema Complemento/metabolismo , Células Epiteliais/metabolismo , Células Epiteliais/virologia , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Inflamação/metabolismo , Inflamação/virologia , Pulmão/metabolismo , Células-Tronco Neurais/metabolismo , Neurônios/metabolismo , Neurônios/virologia , Organoides/metabolismo , Serina Endopeptidases/metabolismo , Transdução de Sinais/fisiologia , Células-Tronco/metabolismo , Células-Tronco/virologiaRESUMO
Glioblastoma multiforme (GBM) is the most lethal primary brain tumor characterized by high cellular and molecular heterogeneity, hypervascularization, and innate drug resistance. Cellular components and extracellular matrix (ECM) are the two primary sources of heterogeneity in GBM. Here, biomimetic tri-regional GBM models with tumor regions, acellular ECM regions, and an endothelial region with regional stiffnesses patterned corresponding to the GBM stroma, pathological or normal brain parenchyma, and brain capillaries, are developed. Patient-derived GBM cells, human endothelial cells, and hyaluronic acid derivatives are used to generate a species-matched and biochemically relevant microenvironment. This in vitro study demonstrates that biophysical cues are involved in various tumor cell behaviors and angiogenic potentials and promote different molecular subtypes of GBM. The stiff models are enriched in the mesenchymal subtype, exhibit diffuse invasion of tumor cells, and induce protruding angiogenesis and higher drug resistance to temozolomide. Meanwhile, the soft models demonstrate enrichment in the classical subtype and support expansive cell growth. The three-dimensional bioprinting technology utilized in this study enables rapid, flexible, and reproducible patient-specific GBM modeling with biophysical heterogeneity that can be employed by future studies as a tunable system to interrogate GBM disease mechanisms and screen drug compounds.
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Bioimpressão , Neoplasias Encefálicas , Glioblastoma , Linhagem Celular Tumoral , Células Endoteliais , Humanos , Microambiente TumoralRESUMO
N6-methyladenosine (m6A) has emerged as the most abundant mRNA modification that regulates gene expression in many physiological processes. m6A modification in RNA controls cellular proliferation and pluripotency and has been implicated in the progression of multiple disease states, including cancer. RNA m6A methylation is controlled by a multiprotein "writer" complex including the enzymatic factor methyltransferase-like protein 3 (METTL3) that regulates methylation and two "eraser" proteins, RNA demethylase ALKBH5 (ALKBH5) and fat mass- and obesity-associated protein (FTO), that demethylate m6A in transcripts. FTO can also demethylate N6,2'-O-dimethyladenosine (m6Am), which is found adjacent to the m7G cap structure in mRNA. FTO has recently gained interest as a potential cancer target, and small molecule FTO inhibitors such as meclofenamic acid have been shown to prevent tumor progression in both acute myeloid leukemia and glioblastoma in vivo models. However, current FTO inhibitors are unsuitable for clinical applications due to either poor target selectivity or poor pharmacokinetics. In this work, we describe the structure-based design, synthesis, and biochemical evaluation of a new class of FTO inhibitors. Rational design of 20 small molecules with low micromolar IC50's and specificity toward FTO over ALKBH5 identified two competitive inhibitors FTO-02 and FTO-04. Importantly, FTO-04 prevented neurosphere formation in patient-derived glioblastoma stem cells (GSCs) without inhibiting the growth of healthy neural stem cell-derived neurospheres. Finally, FTO-04 increased m6A and m6Am levels in GSCs consistent with FTO inhibition. These results support FTO-04 as a potential new lead for treatment of glioblastoma.
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Dioxigenase FTO Dependente de alfa-Cetoglutarato/antagonistas & inibidores , Antineoplásicos/farmacologia , Inibidores Enzimáticos/farmacologia , Pirimidinas/farmacologia , Adenosina/análogos & derivados , Adenosina/química , Dioxigenase FTO Dependente de alfa-Cetoglutarato/química , Dioxigenase FTO Dependente de alfa-Cetoglutarato/metabolismo , Antineoplásicos/síntese química , Antineoplásicos/metabolismo , Sítios de Ligação , Desmetilação/efeitos dos fármacos , Desenho de Fármacos , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/metabolismo , Humanos , Simulação de Acoplamento Molecular , Células-Tronco Neoplásicas , Ligação Proteica , Pirimidinas/síntese química , Pirimidinas/metabolismo , RNA/química , RNA/metabolismoRESUMO
Methamphetamine (METH) is a potent stimulant that induces a euphoric state but also causes cognitive impairment, neurotoxicity and neurodevelopmental deficits. Yet, the molecular mechanisms by which METH causes neurodevelopmental defects have remained elusive. Here we utilized human cerebral organoids and single-cell RNA sequencing (scRNA-seq) to study the effects of prenatal METH exposure on fetal brain development. We analyzed 20,758 cells from eight untreated and six METH-treated cerebral organoids and found that the organoids developed from embryonic stem cells contained a diverse array of glial and neuronal cell types. We further identified transcriptionally distinct populations of astrocytes and oligodendrocytes within cerebral organoids. Treatment of organoids with METH-induced marked changes in transcription in multiple cell types, including astrocytes and neural progenitor cells. METH also elicited novel astrocyte-specific gene expression networks regulating responses to cytokines, and inflammasome. Moreover, upregulation of immediate early genes, complement factors, apoptosis, and immune response genes suggests a neuroinflammatory program induced by METH regulating neural stem cell proliferation, differentiation, and cell death. Finally, we observed marked METH-induced changes in neuroinflammatory and cytokine gene expression at the RNA and protein levels. Our data suggest that human cerebral organoids represent a model system to study drug-induced neuroinflammation at single-cell resolution.
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Estimulantes do Sistema Nervoso Central , Metanfetamina , Astrócitos , Humanos , Neurônios , OrganoidesRESUMO
Neurogenesis is a developmental process that involves fine-tuned coordination between self-renewal, proliferation, and differentiation of neural stem cells (NSCs) into neurons. However, early-life assault with environmental toxicants interferes with the regular function of genes, proteins, and other molecules that build brain architecture resulting in attenuated neurogenesis. Cypermethrin is a class II synthetic pyrethroid pesticide extensively used in agriculture, veterinary, and residential applications due to its low mammalian toxicity, high bio-efficacy, and enhanced stability. Despite reports on cypermethrin-mediated behavioral and biochemical alterations, till now, no study implicates whether cypermethrin exposure has any effect on neurogenesis. Therefore, the present study was undertaken to comprehend the effects of cypermethrin treatment on embryonic and adult neurogenesis. We found that cypermethrin exposure led to a considerable decrease in the BrdU/Sox-2+, BrdU/Dcx+, and BrdU/NeuN+ co-labeled cells indicating that cypermethrin treatment decreases NSC proliferation and generation of mature and functional neurons. On the contrary, the generation of BrdU/S100ß+ glial cells was increased resulting in neurogliogenesis imbalance in the hippocampus. Further, cypermethrin treatment also led to an increased number of BrdU/cleaved caspase-3+ and Fluoro-Jade B+ cells suggesting an induction of apoptosis in NSCs and increased degeneration of neurons in the hippocampus. Overall, these results explicate that cypermethrin exposure not only reduces the NSC pool but also disturbs the neuron-astrocyte ratio and potentiates neurodegeneration in the hippocampus, leading to cognitive dysfunctions in rats.
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Linhagem da Célula , Cognição/efeitos dos fármacos , Hipocampo/patologia , Hipocampo/fisiopatologia , Neurogênese/efeitos dos fármacos , Neurônios/patologia , Piretrinas/toxicidade , Animais , Apoptose/efeitos dos fármacos , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Astrócitos/patologia , Diferenciação Celular/efeitos dos fármacos , Linhagem da Célula/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Autorrenovação Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Giro Denteado/efeitos dos fármacos , Giro Denteado/patologia , Proteína Duplacortina , Feminino , Masculino , Mitose/efeitos dos fármacos , Degeneração Neural/patologia , Células-Tronco Neurais/metabolismo , Neurônios/efeitos dos fármacos , Ratos WistarAssuntos
Teste de Ácido Nucleico para COVID-19/métodos , COVID-19/diagnóstico , Primers do DNA/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , SARS-CoV-2/isolamento & purificação , Simulação por Computador , Humanos , SARS-CoV-2/genética , Sensibilidade e EspecificidadeRESUMO
Zika virus (ZIKV) is an emerging flavivirus, which when passed through vertical transmission from mother to developing fetus can lead to developmental abnormalities, including microcephaly. While there is mounting evidence that suggests a causal relationship between ZIKV infection and microcephaly, the mechanisms by which ZIKV induces these changes remain to be elucidated. Here, we demonstrate that ZIKV infection of neural stems cells, both in vitro and in vivo, induces macroautophagy to enhance viral replication. At the same time, ZIKV downregulates a number of essential selective autophagy genes, including the Fanconi anemia (FA) pathway genes. Bioinformatics analyses indicate that the transcription factor E2F4 promotes FANCC expression and is downregulated upon ZIKV infection. Gain and loss of function assays indicate that FANCC is essential for selective autophagy and acts as a negative regulator of ZIKV replication. Finally, we show that Fancc KO mice have increased ZIKV infection and autophagy protein levels in various brain regions. Taken together, ZIKV downregulates FANCC to modulate the host antiviral response and simultaneously attenuate neuronal growth.
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Anemia de Fanconi , Células-Tronco Neurais , Infecção por Zika virus , Zika virus , Animais , Autofagia , Linhagem Celular , Anemia de Fanconi/genética , Proteína do Grupo de Complementação C da Anemia de Fanconi , Macroautofagia , Camundongos , Replicação Viral , Zika virus/genética , Infecção por Zika virus/genéticaRESUMO
Coronavirus disease 2019 (COVID-19) is caused by SARS-CoV-2 and has spread across the globe. SARS-CoV-2 is a highly infectious virus with no vaccine or antiviral therapy available to control the pandemic; therefore, it is crucial to understand the mechanisms of viral pathogenesis and the host immune responses to SARS-CoV-2. SARS-CoV-2 is a new member of the betacoronavirus genus like other closely related viruses including SARS-CoV and Middle East respiratory syndrome coronavirus (MERS-CoV). Both SARS-CoV and MERS-CoV have caused serious outbreaks and epidemics in the past eighteen years. Here, we report that one of the interferon-stimulated genes (ISGs), cholesterol 25-hydroxylase (CH25H), is induced by SARS-CoV-2 infection in vitro and in COVID-19-infected patients. CH25H converts cholesterol to 25-hydrocholesterol (25HC) and 25HC shows broad anti-coronavirus activity by blocking membrane fusion. Furthermore, 25HC inhibits USA-WA1/2020 SARS-CoV-2 infection in lung epithelial cells and viral entry in human lung organoids. Mechanistically, 25HC inhibits viral membrane fusion by activating the ER-localized acyl-CoA:cholesterol acyltransferase (ACAT) which leads to the depletion of accessible cholesterol from the plasma membrane. Altogether, our results shed light on a potentially broad antiviral mechanism by 25HC through depleting accessible cholesterol on the plasma membrane to suppress virus-cell fusion. Since 25HC is a natural product with no known toxicity at effective concentrations, it provides a potential therapeutic candidate for COVID-19 and emerging viral diseases in the future.