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1.
EMBO J ; 39(21): e106057, 2020 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-32944968

RESUMO

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.


Assuntos
Antivirais/farmacologia , Betacoronavirus/efeitos dos fármacos , Colesterol/metabolismo , Infecções por Coronavirus/tratamento farmacológico , Pneumonia Viral/tratamento farmacológico , Mucosa Respiratória/virologia , Esteroide Hidroxilases/farmacologia , Internalização do Vírus/efeitos dos fármacos , Acetil-CoA C-Acetiltransferase/metabolismo , Animais , COVID-19 , Linhagem Celular , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Chlorocebus aethiops , Ativação Enzimática/efeitos dos fármacos , Humanos , Coronavírus da Síndrome Respiratória do Oriente Médio/efeitos dos fármacos , Organoides/virologia , Pandemias , Mucosa Respiratória/efeitos dos fármacos , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/efeitos dos fármacos , SARS-CoV-2 , Células Vero , Tratamento Farmacológico da COVID-19
2.
EMBO J ; 38(8)2019 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-30918008

RESUMO

Long noncoding RNAs (lncRNAs) can regulate target gene expression by acting in cis (locally) or in trans (non-locally). Here, we performed genome-wide expression analysis of Toll-like receptor (TLR)-stimulated human macrophages to identify pairs of cis-acting lncRNAs and protein-coding genes involved in innate immunity. A total of 229 gene pairs were identified, many of which were commonly regulated by signaling through multiple TLRs and were involved in the cytokine responses to infection by group B Streptococcus We focused on elucidating the function of one lncRNA, named lnc-MARCKS or ROCKI (Regulator of Cytokines and Inflammation), which was induced by multiple TLR stimuli and acted as a master regulator of inflammatory responses. ROCKI interacted with APEX1 (apurinic/apyrimidinic endodeoxyribonuclease 1) to form a ribonucleoprotein complex at the MARCKS promoter. In turn, ROCKI-APEX1 recruited the histone deacetylase HDAC1, which removed the H3K27ac modification from the promoter, thus reducing MARCKS transcription and subsequent Ca2+ signaling and inflammatory gene expression. Finally, genetic variants affecting ROCKI expression were linked to a reduced risk of certain inflammatory and infectious disease in humans, including inflammatory bowel disease and tuberculosis. Collectively, these data highlight the importance of cis-acting lncRNAs in TLR signaling, innate immunity, and pathophysiological inflammation.


Assuntos
Regulação da Expressão Gênica , Imunidade Inata/imunologia , Inflamação/imunologia , Macrófagos/imunologia , RNA Longo não Codificante/metabolismo , Infecções Estreptocócicas/microbiologia , Receptores Toll-Like/metabolismo , Células Cultivadas , Citocinas/metabolismo , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/genética , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/metabolismo , Genoma Humano , Histona Desacetilase 1/genética , Histona Desacetilase 1/metabolismo , Humanos , Inflamação/genética , Inflamação/microbiologia , Macrófagos/metabolismo , Macrófagos/microbiologia , Substrato Quinase C Rico em Alanina Miristoilada/genética , Substrato Quinase C Rico em Alanina Miristoilada/metabolismo , Regiões Promotoras Genéticas , RNA Longo não Codificante/genética , Infecções Estreptocócicas/imunologia , Streptococcus agalactiae/isolamento & purificação , Receptores Toll-Like/genética
3.
Mol Psychiatry ; 26(4): 1194-1207, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-32051547

RESUMO

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.


Assuntos
Estimulantes do Sistema Nervoso Central , Metanfetamina , Astrócitos , Humanos , Neurônios , Organoides
4.
EMBO Rep ; 21(12): e49183, 2020 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-33073500

RESUMO

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.


Assuntos
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/genética
5.
Small ; 17(15): e2006050, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33502104

RESUMO

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.


Assuntos
Bioimpressão , Neoplasias Encefálicas , Glioblastoma , Linhagem Celular Tumoral , Células Endoteliais , Humanos , Microambiente Tumoral
6.
J Biol Chem ; 292(47): 19423-19440, 2017 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-28982980

RESUMO

The widely used carbamate pesticide carbofuran causes neurophysiological and neurobehavioral deficits in rodents and humans and therefore poses serious health hazards around the world. Previously, we reported that gestational carbofuran exposure has detrimental effects on hippocampal neurogenesis, the generation of new neurons from neural stem cells (NSC), in offspring. However, the underlying cellular and molecular mechanisms for carbofuran-impaired neurogenesis remain unknown. Herein, we observed that chronic carbofuran exposure from gestational day 7 to postnatal day 21 altered expression of genes and transcription factors and levels of proteins involved in neurogenesis and the TGF-ß pathway (i.e. TGF-ß; SMAD-2, -3, and -7; and SMURF-2) in the rat hippocampus. We found that carbofuran increases TGF-ß signaling (i.e. increased phosphorylated SMAD-2/3 and reduced SMAD-7 expression) in the hippocampus, which reduced NSC proliferation because of increased p21 levels and reduced cyclin D1 levels. Moreover, the carbofuran-altered TGF-ß signaling impaired neuronal differentiation (BrdU/DCX+ and BrdU/NeuN+ cells) and increased apoptosis and neurodegeneration in the hippocampus. Blockade of the TGF-ß pathway with the specific inhibitor SB431542 and via SMAD-3 siRNA prevented carbofuran-mediated inhibition of neurogenesis in both hippocampal NSC cultures and the hippocampus, suggesting the specific involvement of this pathway. Of note, both in vitro and in vivo studies indicated that TGF-ß pathway attenuation reverses carbofuran's inhibitory effects on neurogenesis and associated learning and memory deficits. These results suggest that carbofuran inhibits NSC proliferation and neuronal differentiation by altering TGF-ß signaling. Therefore, we conclude that TGF-ß may represent a potential therapeutic target against carbofuran-mediated neurotoxicity and neurogenesis disruption.


Assuntos
Carbofurano/farmacologia , Hipocampo/efeitos dos fármacos , Células-Tronco Neurais/efeitos dos fármacos , Neurogênese/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Proteína Smad3/antagonistas & inibidores , Fator de Crescimento Transformador beta/antagonistas & inibidores , Animais , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Proteína Duplacortina , Feminino , Hipocampo/citologia , Hipocampo/metabolismo , Células-Tronco Neurais/citologia , Células-Tronco Neurais/metabolismo , Neurônios/citologia , Neurônios/metabolismo , Ratos , Ratos Wistar , Transdução de Sinais
7.
J Biol Chem ; 291(31): 15923-39, 2016 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-27252377

RESUMO

The regulatory dynamics of mitochondria comprises well orchestrated distribution and mitochondrial turnover to maintain the mitochondrial circuitry and homeostasis inside the cells. Several pieces of evidence suggested impaired mitochondrial dynamics and its association with the pathogenesis of neurodegenerative disorders. We found that chronic exposure of synthetic xenoestrogen bisphenol A (BPA), a component of consumer plastic products, impaired autophagy-mediated mitochondrial turnover, leading to increased oxidative stress, mitochondrial fragmentation, and apoptosis in hippocampal neural stem cells (NSCs). It also inhibited hippocampal derived NSC proliferation and differentiation, as evident by the decreased number of BrdU- and ß-III tubulin-positive cells. All these effects were reversed by the inhibition of oxidative stress using N-acetyl cysteine. BPA up-regulated the levels of Drp-1 (dynamin-related protein 1) and enhanced its mitochondrial translocation, with no effect on Fis-1, Mfn-1, Mfn-2, and Opa-1 in vitro and in the hippocampus. Moreover, transmission electron microscopy studies suggested increased mitochondrial fission and accumulation of fragmented mitochondria and decreased elongated mitochondria in the hippocampus of the rat brain. Impaired mitochondrial dynamics by BPA resulted in increased reactive oxygen species and malondialdehyde levels, disruption of mitochondrial membrane potential, and ATP decline. Pharmacological (Mdivi-1) and genetic (Drp-1siRNA) inhibition of Drp-1 reversed BPA-induced mitochondrial dysfunctions, fragmentation, and apoptosis. Interestingly, BPA-mediated inhibitory effects on NSC proliferation and neuronal differentiations were also mitigated by Drp-1 inhibition. On the other hand, Drp-1 inhibition blocked BPA-mediated Drp-1 translocation, leading to decreased apoptosis of NSC. Overall, our studies implicate Drp-1 as a potential therapeutic target against BPA-mediated impaired mitochondrial dynamics and neurodegeneration in the hippocampus.


Assuntos
Compostos Benzidrílicos/toxicidade , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Dinaminas/metabolismo , Hipocampo/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/metabolismo , Células-Tronco Neurais/metabolismo , Fenóis/toxicidade , Trifosfato de Adenosina/metabolismo , Animais , Apoptose/efeitos dos fármacos , Hipocampo/patologia , Masculino , Mitocôndrias/patologia , Células-Tronco Neurais/patologia , Transporte Proteico/efeitos dos fármacos , Ratos , Ratos Wistar
9.
J Biol Chem ; 290(47): 28540-28558, 2015 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-26420483

RESUMO

Neurogenesis involves generation of new neurons through finely tuned multistep processes, such as neural stem cell (NSC) proliferation, migration, differentiation, and integration into existing neuronal circuitry in the dentate gyrus of the hippocampus and subventricular zone. Adult hippocampal neurogenesis is involved in cognitive functions and altered in various neurodegenerative disorders, including Alzheimer disease (AD). Ethosuximide (ETH), an anticonvulsant drug is used for the treatment of epileptic seizures. However, the effects of ETH on adult hippocampal neurogenesis and the underlying cellular and molecular mechanism(s) are yet unexplored. Herein, we studied the effects of ETH on rat multipotent NSC proliferation and neuronal differentiation and adult hippocampal neurogenesis in an amyloid ß (Aß) toxin-induced rat model of AD-like phenotypes. ETH potently induced NSC proliferation and neuronal differentiation in the hippocampus-derived NSC in vitro. ETH enhanced NSC proliferation and neuronal differentiation and reduced Aß toxin-mediated toxicity and neurodegeneration, leading to behavioral recovery in the rat AD model. ETH inhibited Aß-mediated suppression of neurogenic and Akt/Wnt/ß-catenin pathway gene expression in the hippocampus. ETH activated the PI3K·Akt and Wnt·ß-catenin transduction pathways that are known to be involved in the regulation of neurogenesis. Inhibition of the PI3K·Akt and Wnt·ß-catenin pathways effectively blocked the mitogenic and neurogenic effects of ETH. In silico molecular target prediction docking studies suggest that ETH interacts with Akt, Dkk-1, and GSK-3ß. Our findings suggest that ETH stimulates NSC proliferation and differentiation in vitro and adult hippocampal neurogenesis via the PI3K·Akt and Wnt·ß-catenin signaling.


Assuntos
Doença de Alzheimer/induzido quimicamente , Peptídeos beta-Amiloides/toxicidade , Etossuximida/farmacologia , Hipocampo/efeitos dos fármacos , Neurogênese/efeitos dos fármacos , Doença de Alzheimer/enzimologia , Doença de Alzheimer/metabolismo , Animais , Diferenciação Celular , Proliferação de Células , Transtornos Cognitivos/induzido quimicamente , Transtornos Cognitivos/enzimologia , Transtornos Cognitivos/metabolismo , Modelos Animais de Doenças , Hipocampo/enzimologia , Hipocampo/metabolismo , Hipocampo/patologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Proteínas Wnt/metabolismo , beta Catenina/metabolismo
11.
J Biol Chem ; 290(34): 21163-21184, 2015 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-26139607

RESUMO

The human health hazards related to persisting use of bisphenol-A (BPA) are well documented. BPA-induced neurotoxicity occurs with the generation of oxidative stress, neurodegeneration, and cognitive dysfunctions. However, the cellular and molecular mechanism(s) of the effects of BPA on autophagy and association with oxidative stress and apoptosis are still elusive. We observed that BPA exposure during the early postnatal period enhanced the expression and the levels of autophagy genes/proteins. BPA treatment in the presence of bafilomycin A1 increased the levels of LC3-II and SQSTM1 and also potentiated GFP-LC3 puncta index in GFP-LC3-transfected hippocampal neural stem cell-derived neurons. BPA-induced generation of reactive oxygen species and apoptosis were mitigated by a pharmacological activator of autophagy (rapamycin). Pharmacological (wortmannin and bafilomycin A1) and genetic (beclin siRNA) inhibition of autophagy aggravated BPA neurotoxicity. Activation of autophagy against BPA resulted in intracellular energy sensor AMP kinase (AMPK) activation, increased phosphorylation of raptor and acetyl-CoA carboxylase, and decreased phosphorylation of ULK1 (Ser-757), and silencing of AMPK exacerbated BPA neurotoxicity. Conversely, BPA exposure down-regulated the mammalian target of rapamycin (mTOR) pathway by phosphorylation of raptor as a transient cell's compensatory mechanism to preserve cellular energy pool. Moreover, silencing of mTOR enhanced autophagy, which further alleviated BPA-induced reactive oxygen species generation and apoptosis. BPA-mediated neurotoxicity also resulted in mitochondrial loss, bioenergetic deficits, and increased PARKIN mitochondrial translocation, suggesting enhanced mitophagy. These results suggest implication of autophagy against BPA-mediated neurodegeneration through involvement of AMPK and mTOR pathways. Hence, autophagy, which arbitrates cell survival and demise during stress conditions, requires further assessment to be established as a biomarker of xenoestrogen exposure.


Assuntos
Autofagia/efeitos dos fármacos , Compostos Benzidrílicos/toxicidade , Poluentes Ambientais/toxicidade , Hipocampo/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Fenóis/toxicidade , Proteínas Quinases/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Quinases Proteína-Quinases Ativadas por AMP , Androstadienos/farmacologia , Animais , Animais Recém-Nascidos , Proteínas Reguladoras de Apoptose/antagonistas & inibidores , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Autofagia/genética , Proteína Beclina-1 , Compostos Benzidrílicos/antagonistas & inibidores , Poluentes Ambientais/antagonistas & inibidores , Regulação da Expressão Gênica , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Hipocampo/metabolismo , Hipocampo/patologia , Humanos , Macrolídeos/farmacologia , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Neurônios/metabolismo , Neurônios/patologia , Estresse Oxidativo , Fenóis/antagonistas & inibidores , Cultura Primária de Células , Proteínas Quinases/genética , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Proteína Sequestossoma-1 , Transdução de Sinais , Sirolimo/farmacologia , Serina-Treonina Quinases TOR/genética , Wortmanina
12.
Hum Mol Genet ; 21(15): 3474-88, 2012 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-22589249

RESUMO

Huntington's disease (HD) is an incurable neurological disorder caused by an abnormal glutamine repeat expansion in the huntingtin (Htt) protein. In the present studies, we investigated the role of Transducers of Regulated cAMP response element-binding (CREB) protein activity (TORCs) in HD, since TORCs play an important role in the expression of the transcriptional co-regulator peroxisome proliferator-activated receptor gamma coactivator 1α (PGC-1α), whose expression is impaired in HD. We found significantly decreased TORC1 expression levels in STHdhQ111 cells expressing mutant Htt, in the striatum of NLS-N171-82Q, R6/2 and HdhQ111 HD transgenic mice and in postmortem striatal tissue from HD patients. TORC1 overexpression in wild-type (WT) and Htt striatal cells increased CREB mRNA and protein levels, PGC-1α promoter activity, mRNA expression of the PGC-1α, NRF-1, Tfam and CytC genes, mitochondrial DNA content, mitochondrial activity and mitochondrial membrane potential. TORC1 overexpression also increased the resistance of striatal cells to 3-nitropropionic (3-NP) acid-mediated toxicity. In cultured WT and mutant Htt striatal cells, small hairpin RNA-mediated TORC1 knockdown resulted in decreased PGC-1α expression and increased susceptibility to 3-NP-induced toxicity. Overexpression of PGC-1α partially prevented TORC1 knockdown-mediated increased susceptibility of Htt striatal cells to 3-NP. Specific knockdown of TORC1 in the striatum of NLS-N171-82Q HD transgenic mice induced neurodegeneration. Lastly, knockdown of Htt prevents transcriptional repression of TORC1 and CREB in Htt striatal cells. These findings show that impaired expression and function of TORC1, which results in a reduction in PGC-1α, plays an important role in mitochondrial dysfunction in HD.


Assuntos
Doença de Huntington/genética , Doença de Huntington/metabolismo , Transativadores/genética , Fatores de Transcrição/genética , Animais , Células Cultivadas , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Humanos , Proteína Huntingtina , Camundongos , Camundongos Transgênicos , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Neurônios/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , RNA Mensageiro/metabolismo , Proteínas da Membrana Plasmática de Transporte de Serotonina/genética , Proteínas da Membrana Plasmática de Transporte de Serotonina/metabolismo , Transativadores/metabolismo , Fatores de Transcrição/metabolismo , Transcrição Gênica
13.
bioRxiv ; 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38746287

RESUMO

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.

14.
Heliyon ; 9(9): e19601, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37809493

RESUMO

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.

15.
Environ Sci Pollut Res Int ; 30(17): 49666-49684, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36781668

RESUMO

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.


Assuntos
Ruído dos Transportes , Humanos , Exposição Ambiental , Cidades , Inquéritos e Questionários , Acústica
16.
J Med Chem ; 65(4): 2866-2879, 2022 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-34570513

RESUMO

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.


Assuntos
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-19
17.
ACS Chem Biol ; 16(2): 324-333, 2021 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-33412003

RESUMO

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.


Assuntos
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/metabolismo
18.
Stem Cell Reports ; 16(3): 437-445, 2021 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-33631122

RESUMO

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.


Assuntos
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/virologia
19.
Mol Neurobiol ; 58(1): 263-280, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32920670

RESUMO

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.


Assuntos
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 Wistar
20.
Front Med (Lausanne) ; 8: 639208, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34722554

RESUMO

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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