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1.
Nat Commun ; 11(1): 4684, 2020 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-32943635

RESUMO

Cancer cells have a characteristic metabolism, mostly caused by alterations in signal transduction networks rather than mutations in metabolic enzymes. For metabolic drugs to be cancer-selective, signaling alterations need to be identified that confer a druggable vulnerability. Here, we demonstrate that many tumor cells with an acquired cancer drug resistance exhibit increased sensitivity to mechanistically distinct inhibitors of cancer metabolism. We demonstrate that this metabolic vulnerability is driven by mTORC1, which promotes resistance to chemotherapy and targeted cancer drugs, but simultaneously suppresses autophagy. We show that autophagy is essential for tumor cells to cope with therapeutic perturbation of metabolism and that mTORC1-mediated suppression of autophagy is required and sufficient for generating a metabolic vulnerability leading to energy crisis and apoptosis. Our study links mTOR-induced cancer drug resistance to autophagy defects as a cause of a metabolic liability and opens a therapeutic window for the treatment of otherwise therapy-refractory tumor patients.


Assuntos
Antineoplásicos/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Animais , Apoptose/efeitos dos fármacos , Autofagia/genética , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Desoxiglucose , Tratamento Farmacológico , Feminino , Humanos , Neoplasias Pulmonares , Masculino , Alvo Mecanístico do Complexo 1 de Rapamicina , Camundongos , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
2.
J Toxicol Sci ; 45(9): 559-567, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32879255

RESUMO

Lead is a main threat to human health due to its neurotoxicity and the astrocyte is known to be a common deposit site of lead in vivo. However, the detailed mechanisms related to lead exposure in the astrocytes were unclear. In order to deeply investigate this issue, we used Sprague-Dawley (SD) rats and astrocytes isolated from the hippocampus of SD rats to establish the lead-exposed animal and cell models through treating with lead acetate. The expression levels of GFAP, LC3, and p62 in the rat hippocampus were detected by immunofluorescence and Western blot after lead exposure. The effects of autophagy on lead-exposed astrocytes were studied by further autophagy inhibitor 3-methyladenine (3-MA) induction. Transmission electron microscopy was used to observe autophagosomes in astrocytes after lead acetate treatment, followed by assessing related autophagy protein markers. In addition, some inflammatory cytokines and oxidative stress markers were also evaluated after lead exposure and 3-MA administration. We found that lead exposure induced activation of astrocytes, as evidenced by increased GFAP levels and GFAP-positive staining cells in the rat hippocampus. Moreover, lead exposure induced autophagy in astrocytes, as evidenced by increased LC3II and Beclin 1 protein levels and decreased p62 expression in both the rat hippocampus and astrocytes, and it was confirmed that this autophagy was activated through blocking the downstream Akt/target of the rapamycin (mTOR) pathway in astrocytes. Furthermore, it was shown that treatment of lead acetate increased the release of tumor necrosis factor-α (TNF-α) and interleukin-1ß (IL-1ß), and the accumulation of malondialdehyde (MDA) and myeloperoxidase (MPO) in astrocytes, which could be alleviated by further 3-MA induction. Therefore, we conclude that lead exposure can induce the autophagy of astrocytes via blocking the Akt/mTOR pathway, leading to accelerated release of inflammatory factors and oxidative stress indicators in astrocytes.


Assuntos
Astrócitos/metabolismo , Astrócitos/fisiologia , Autofagia/efeitos dos fármacos , Autofagia/genética , Compostos Organometálicos/toxicidade , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Animais , Células Cultivadas , Proteína Glial Fibrilar Ácida/genética , Proteína Glial Fibrilar Ácida/metabolismo , Hipocampo/citologia , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Masculino , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Estresse Oxidativo/genética , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
3.
Trends Immunol ; 41(10): 856-859, 2020 10.
Artigo em Inglês | MEDLINE | ID: covidwho-703987

RESUMO

Coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and mainly affects the lungs. Sarcoidosis is an autoinflammatory disease characterized by the diffusion of granulomas in the lungs and other organs. Here, we discuss how the two diseases might involve some common mechanistic cellular pathways around the regulation of autophagy.


Assuntos
Autofagia/efeitos dos fármacos , Betacoronavirus/patogenicidade , Infecções por Coronavirus/tratamento farmacológico , Pneumonia Viral/tratamento farmacológico , Edema Pulmonar/tratamento farmacológico , Sarcoidose/tratamento farmacológico , Síndrome Respiratória Aguda Grave/tratamento farmacológico , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Autofagia/genética , Azitromicina/uso terapêutico , Betacoronavirus/crescimento & desenvolvimento , Cloroquina/uso terapêutico , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/genética , Infecções por Coronavirus/virologia , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Humanos , Isoniazida/uso terapêutico , Pulmão/efeitos dos fármacos , Pulmão/patologia , Pulmão/virologia , Pandemias , Pneumonia Viral/epidemiologia , Pneumonia Viral/genética , Pneumonia Viral/virologia , Edema Pulmonar/epidemiologia , Edema Pulmonar/genética , Edema Pulmonar/virologia , Rifampina/uso terapêutico , Sarcoidose/epidemiologia , Sarcoidose/genética , Sarcoidose/virologia , Síndrome Respiratória Aguda Grave/epidemiologia , Síndrome Respiratória Aguda Grave/genética , Síndrome Respiratória Aguda Grave/virologia , Índice de Gravidade de Doença
4.
Trends Immunol ; 41(10): 856-859, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32863134

RESUMO

Coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and mainly affects the lungs. Sarcoidosis is an autoinflammatory disease characterized by the diffusion of granulomas in the lungs and other organs. Here, we discuss how the two diseases might involve some common mechanistic cellular pathways around the regulation of autophagy.


Assuntos
Autofagia/efeitos dos fármacos , Betacoronavirus/patogenicidade , Infecções por Coronavirus/tratamento farmacológico , Pneumonia Viral/tratamento farmacológico , Edema Pulmonar/tratamento farmacológico , Sarcoidose/tratamento farmacológico , Síndrome Respiratória Aguda Grave/tratamento farmacológico , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Autofagia/genética , Azitromicina/uso terapêutico , Betacoronavirus/crescimento & desenvolvimento , Cloroquina/uso terapêutico , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/genética , Infecções por Coronavirus/virologia , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Humanos , Isoniazida/uso terapêutico , Pulmão/efeitos dos fármacos , Pulmão/patologia , Pulmão/virologia , Pandemias , Pneumonia Viral/epidemiologia , Pneumonia Viral/genética , Pneumonia Viral/virologia , Edema Pulmonar/epidemiologia , Edema Pulmonar/genética , Edema Pulmonar/virologia , Rifampina/uso terapêutico , Sarcoidose/epidemiologia , Sarcoidose/genética , Sarcoidose/virologia , Síndrome Respiratória Aguda Grave/epidemiologia , Síndrome Respiratória Aguda Grave/genética , Síndrome Respiratória Aguda Grave/virologia , Índice de Gravidade de Doença
5.
Nat Commun ; 11(1): 3806, 2020 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-32732922

RESUMO

Most triple-negative breast cancer (TNBC) patients fail to respond to T cell-mediated immunotherapies. Unfortunately, the molecular determinants are still poorly understood. Breast cancer is the disease genetically linked to a deficiency in autophagy. Here, we show that autophagy defects in TNBC cells inhibit T cell-mediated tumour killing in vitro and in vivo. Mechanistically, we identify Tenascin-C as a candidate for autophagy deficiency-mediated immunosuppression, in which Tenascin-C is Lys63-ubiquitinated by Skp2, particularly at Lys942 and Lys1882, thus promoting its recognition by p62 and leading to its selective autophagic degradation. High Tenascin-C expression is associated with poor prognosis and inversely correlated with LC3B expression and CD8+ T cells in TNBC patients. More importantly, inhibition of Tenascin-C in autophagy-impaired TNBC cells sensitizes T cell-mediated tumour killing and improves antitumour effects of single anti-PD1/PDL1 therapy. Our results provide a potential strategy for targeting TNBC with the combination of Tenascin-C blockade and immune checkpoint inhibitors.


Assuntos
Autofagia/imunologia , Linfócitos T CD8-Positivos/imunologia , Tenascina/metabolismo , Neoplasias de Mama Triplo Negativas/imunologia , Evasão Tumoral/imunologia , Animais , Antineoplásicos Imunológicos/farmacologia , Autofagia/genética , Antígeno B7-H1/antagonistas & inibidores , Linfócitos T CD8-Positivos/transplante , Linhagem Celular Tumoral , Feminino , Células HEK293 , Humanos , Imunoterapia Adotiva , Camundongos , Camundongos Endogâmicos BALB C , Camundongos SCID , Prognóstico , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Interferência de RNA , RNA Interferente Pequeno/genética , Proteínas de Ligação a RNA/metabolismo , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/terapia , Evasão Tumoral/genética
6.
Medicine (Baltimore) ; 99(30): e21163, 2020 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-32791689

RESUMO

Autophagy, a major cause of cancer-related death, is correlated with the pathogenesis of various diseases including cancers. Our study aimed to develop an autophagy-related model for predicting prognosis of patients with laryngeal cancer.We analyzed the correlation between expression profiles of autophagy-related genes (ARGs) and clinical outcomes in 111 laryngeal cancer patients from The Cancer Genome Atlas (TCGA). Afterward, gene functional enrichment analyses of gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) were performed to find the major biological attributes. Univariate Cox regression analyses and multivariate Cox regression analyses were performed to screen ARGs whose expression profiles were significantly associated with laryngeal cancer patients overall survival (OS). Furthermore, to provide the doctors and patients with a quantitative method to perform an individualized survival prediction, we constructed a prognostic nomogram.Thirty eight differentially expressed ARGs were screened out in laryngeal cancer patients through the TCGA database. Related functional enrichments may act as tumor-suppressive roles in the tumorigenesis of laryngeal cancer. Subsequently, 4 key prognostic ARGs (IKBKB, ST13, TSC2, and MAP2K7) were identified from all ARGs by the Cox regression model, which significantly correlated with OS in laryngeal cancer. Furthermore, the risk score was constructed, which significantly divided laryngeal cancer patients into high- and low-risk groups. Integrated with clinical characteristics, gender, N and the risk score are very likely associated with patients OS. A prognostic nomogram of ARGs was constructed using the Cox regression model.Our study could provide a valuable prognostic model for predicting the prognosis of laryngeal cancer patients and a new understanding of autophagy in laryngeal cancer.


Assuntos
Autofagia/genética , Neoplasias Laríngeas/genética , Nomogramas , Fatores Etários , Proteínas de Transporte/genética , Perfilação da Expressão Gênica , Humanos , Quinase I-kappa B/genética , Neoplasias Laríngeas/patologia , MAP Quinase Quinase 7/genética , Modelos Biológicos , Estadiamento de Neoplasias , Prognóstico , Modelos de Riscos Proporcionais , Fatores de Risco , Fatores Sexuais , Taxa de Sobrevida , Transcriptoma , Proteína 2 do Complexo Esclerose Tuberosa/genética , Proteínas Supressoras de Tumor/genética
7.
Arch Virol ; 165(10): 2165-2176, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32740830

RESUMO

The PI3K/Akt signalling pathway is a crucial signalling cascade that regulates transcription, protein translation, cell growth, proliferation, cell survival, and metabolism. During viral infection, viruses exploit a variety of cellular pathways, including the well-known PI3K/Akt signalling pathway. Conversely, cells rely on this pathway to stimulate an antiviral response. The PI3K/Akt pathway is manipulated by a number of viruses, including DNA and RNA viruses and retroviruses. The aim of this review is to provide up-to-date information about the role of the PI3K-Akt pathway in infection with members of five different families of negative-sense ssRNA viruses. This pathway is hijacked for viral entry, regulation of endocytosis, suppression of premature apoptosis, viral protein expression, and replication. Although less common, the PI3K/Akt pathway can be downregulated as an immunomodulatory strategy or as a mechanism for inducing autophagy. Moreover, the cell activates this pathway as an antiviral strategy for interferon and cytokine production, among other strategies. Here, we present new data concerning the role of this pathway in infection with the paramyxovirus Newcastle disease virus (NDV). Our data seem to indicate that NDV uses the PI3K/Akt pathway to delay cell death and increase cell survival as a means of improving its replication. The interference of negative-sense ssRNA viruses with this essential pathway might have implications for the development of antiviral therapies.


Assuntos
Regulação da Expressão Gênica , Interações Hospedeiro-Patógeno/genética , Fosfatidilinositol 3-Quinase/genética , Proteínas Proto-Oncogênicas c-akt/genética , Infecções por Vírus de RNA/genética , Apoptose/genética , Autofagia/genética , Autofagia/imunologia , Citocinas/genética , Citocinas/imunologia , Endocitose/genética , Endocitose/imunologia , Filoviridae/genética , Filoviridae/metabolismo , Filoviridae/patogenicidade , Interações Hospedeiro-Patógeno/imunologia , Interferons/genética , Interferons/imunologia , Orthomyxoviridae/genética , Orthomyxoviridae/metabolismo , Orthomyxoviridae/patogenicidade , Paramyxoviridae/genética , Paramyxoviridae/metabolismo , Paramyxoviridae/patogenicidade , Fosfatidilinositol 3-Quinase/imunologia , Pneumovirinae/genética , Pneumovirinae/metabolismo , Pneumovirinae/patogenicidade , Biossíntese de Proteínas , Proteínas Proto-Oncogênicas c-akt/imunologia , Infecções por Vírus de RNA/imunologia , Infecções por Vírus de RNA/virologia , Rhabdoviridae/genética , Rhabdoviridae/metabolismo , Rhabdoviridae/patogenicidade , Transdução de Sinais , Proteínas Virais/genética , Proteínas Virais/imunologia , Internalização do Vírus , Replicação Viral
8.
Nat Commun ; 11(1): 4029, 2020 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-32788597

RESUMO

In autosomal dominant optic atrophy (ADOA), caused by mutations in the mitochondrial cristae biogenesis and fusion protein optic atrophy 1 (Opa1), retinal ganglion cell (RGC) dysfunction and visual loss occur by unknown mechanisms. Here, we show a role for autophagy in ADOA pathogenesis. In RGCs expressing mutated Opa1, active 5' AMP-activated protein kinase (AMPK) and its autophagy effector ULK1 accumulate at axonal hillocks. This AMPK activation triggers localized hillock autophagosome accumulation and mitophagy, ultimately resulting in reduced axonal mitochondrial content that is restored by genetic inhibition of AMPK and autophagy. In C. elegans, deletion of AMPK or of key autophagy and mitophagy genes normalizes the axonal mitochondrial content that is reduced upon mitochondrial dysfunction. In conditional, RGC specific Opa1-deficient mice, depletion of the essential autophagy gene Atg7 normalizes the excess autophagy and corrects the visual defects caused by Opa1 ablation. Thus, our data identify AMPK and autophagy as targetable components of ADOA pathogenesis.


Assuntos
Autofagia , Atrofia Óptica Autossômica Dominante/complicações , Transtornos da Visão/complicações , Adenilato Quinase/metabolismo , Animais , Autofagia/genética , Axônios/patologia , Caenorhabditis elegans/metabolismo , Modelos Animais de Doenças , Ativação Enzimática , GTP Fosfo-Hidrolases/genética , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mitocôndrias/metabolismo , Mitofagia , Mutação/genética , Fosforilação , Células Ganglionares da Retina/patologia
9.
Nat Commun ; 11(1): 4056, 2020 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-32792483

RESUMO

Autophagy has been associated with oncogenesis with one of its emerging key functions being its contribution to the metabolism of tumors. Therefore, deciphering the mechanisms of how autophagy supports tumor cell metabolism is essential. Here, we demonstrate that the inhibition of autophagy induces an accumulation of lipid droplets (LD) due to a decrease in fatty acid ß-oxidation, that leads to a reduction of oxidative phosphorylation (OxPHOS) in acute myeloid leukemia (AML), but not in normal cells. Thus, the autophagic process participates in lipid catabolism that supports OxPHOS in AML cells. Interestingly, the inhibition of OxPHOS leads to LD accumulation with the concomitant inhibition of autophagy. Mechanistically, we show that the disruption of mitochondria-endoplasmic reticulum (ER) contact sites (MERCs) phenocopies OxPHOS inhibition. Altogether, our data establish that mitochondria, through the regulation of MERCs, controls autophagy that, in turn finely tunes lipid degradation to fuel OxPHOS supporting proliferation and growth in leukemia.


Assuntos
Autofagia/fisiologia , Retículo Endoplasmático/genética , Retículo Endoplasmático/metabolismo , Leucemia Mieloide Aguda/metabolismo , Leucemia/metabolismo , Mitocôndrias/metabolismo , Animais , Autofagia/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Proliferação de Células/fisiologia , Citometria de Fluxo , Humanos , Leucemia/genética , Leucemia Mieloide Aguda/patologia , Metabolismo dos Lipídeos/genética , Metabolismo dos Lipídeos/fisiologia , Lipogênese/genética , Lipogênese/fisiologia , Camundongos , Mitocôndrias/genética , Oxirredução , Fosforilação Oxidativa
10.
PLoS Biol ; 18(8): e3000757, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32833957

RESUMO

In eukaryotes, conserved mechanisms ensure that cell growth is coordinated with nutrient availability. Overactive growth during nutrient limitation ("nutrient-growth dysregulation") can lead to rapid cell death. Here, we demonstrate that cells can adapt to nutrient-growth dysregulation by evolving major metabolic defects. Specifically, when yeast lysine-auxotrophic mutant lys- encountered lysine limitation, an evolutionarily novel stress, cells suffered nutrient-growth dysregulation. A subpopulation repeatedly evolved to lose the ability to synthesize organosulfurs (lys-orgS-). Organosulfurs, mainly reduced glutathione (GSH) and GSH conjugates, were released by lys- cells during lysine limitation when growth was dysregulated, but not during glucose limitation when growth was regulated. Limiting organosulfurs conferred a frequency-dependent fitness advantage to lys-orgS- by eliciting a proper slow growth program, including autophagy. Thus, nutrient-growth dysregulation is associated with rapid organosulfur release, which enables the selection of organosulfur auxotrophy to better tune cell growth to the metabolic environment. We speculate that evolutionarily novel stresses can trigger atypical release of certain metabolites, setting the stage for the evolution of new ecological interactions.


Assuntos
Adaptação Fisiológica/genética , Lisina/farmacologia , Redes e Vias Metabólicas/efeitos dos fármacos , Nutrientes/farmacologia , Saccharomyces cerevisiae/metabolismo , Autofagia/efeitos dos fármacos , Autofagia/genética , Evolução Biológica , Glucose/metabolismo , Glucose/farmacologia , Lisina/deficiência , Redes e Vias Metabólicas/genética , Nitrogênio/metabolismo , Nitrogênio/farmacologia , Nutrientes/metabolismo , Ribossomos/efeitos dos fármacos , Ribossomos/metabolismo , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crescimento & desenvolvimento , Sirolimo/farmacologia , Estresse Fisiológico
11.
Nat Commun ; 11(1): 4150, 2020 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-32811819

RESUMO

The systemic decline in autophagic activity with age impairs homeostasis in several tissues, leading to age-related diseases. A mechanistic understanding of adipocyte dysfunction with age could help to prevent age-related metabolic disorders, but the role of autophagy in aged adipocytes remains unclear. Here we show that, in contrast to other tissues, aged adipocytes upregulate autophagy due to a decline in the levels of Rubicon, a negative regulator of autophagy. Rubicon knockout in adipocytes causes fat atrophy and hepatic lipid accumulation due to reductions in the expression of adipogenic genes, which can be recovered by activation of PPARγ. SRC-1 and TIF2, coactivators of PPARγ, are degraded by autophagy in a manner that depends on their binding to GABARAP family proteins, and are significantly downregulated in Rubicon-ablated or aged adipocytes. Hence, we propose that age-dependent decline in adipose Rubicon exacerbates metabolic disorders by promoting excess autophagic degradation of SRC-1 and TIF2.


Assuntos
Adipócitos/metabolismo , Envelhecimento/fisiologia , Autofagia/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Doenças Metabólicas/metabolismo , Adipócitos/patologia , Adipogenia/genética , Tecido Adiposo/citologia , Tecido Adiposo/metabolismo , Adiposidade/genética , Animais , Proteínas Reguladoras de Apoptose/metabolismo , Autofagia/fisiologia , Fígado Gorduroso/genética , Fígado Gorduroso/metabolismo , Técnicas de Inativação de Genes , Glucose/genética , Glucose/metabolismo , Células HEK293 , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Metabolismo dos Lipídeos/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Associadas aos Microtúbulos/metabolismo , Coativador 1 de Receptor Nuclear/metabolismo , Coativador 2 de Receptor Nuclear/metabolismo , PPAR gama/metabolismo
12.
Mol Cell ; 79(6): 963-977.e3, 2020 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-32735772

RESUMO

Autophagic degradation of the endoplasmic reticulum (ER-phagy) is triggered by ER stress in diverse organisms. However, molecular mechanisms governing ER stress-induced ER-phagy remain insufficiently understood. Here we report that ER stress-induced ER-phagy in the fission yeast Schizosaccharomyces pombe requires Epr1, a soluble Atg8-interacting ER-phagy receptor. Epr1 localizes to the ER through interacting with integral ER membrane proteins VAPs. Bridging an Atg8-VAP association is the main ER-phagy role of Epr1, as it can be bypassed by an artificial Atg8-VAP tether. VAPs contribute to ER-phagy not only by tethering Atg8 to the ER membrane, but also by maintaining the ER-plasma membrane contact. Epr1 is upregulated during ER stress by the unfolded protein response (UPR) regulator Ire1. Loss of Epr1 reduces survival against ER stress. Conversely, increasing Epr1 expression suppresses the ER-phagy defect and ER stress sensitivity of cells lacking Ire1. Our findings expand and deepen the molecular understanding of ER-phagy.


Assuntos
Estresse do Retículo Endoplasmático/genética , Endorribonucleases/genética , Proteínas R-SNARE/genética , Autofagossomos/metabolismo , Autofagia/genética , Família da Proteína 8 Relacionada à Autofagia/genética , Retículo Endoplasmático/genética , Regulação Fúngica da Expressão Gênica/genética , Proteólise , Schizosaccharomyces/genética , Proteínas de Schizosaccharomyces pombe/genética , Resposta a Proteínas não Dobradas/genética
13.
Adv Exp Med Biol ; 1207: 581-584, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32671776

RESUMO

Asthma is one of the most common diseases of the respiratory system, with typical pathogenesis and pathological changes. The current research shows that autophagy is mainly involved in the pathogenesis of asthma by regulating the body's innate and adaptive immune responses. At the same time, a large number of epidemiological studies have shown that multiple autophagy genes affect the risk of asthma at the level of genetic polymorphism. This chapter will explore the relationship between autophagy and asthma.


Assuntos
Asma , Autofagia , Asma/genética , Asma/imunologia , Autofagia/genética , Autofagia/imunologia , Humanos , Polimorfismo Genético
14.
Life Sci ; 256: 118022, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32610163

RESUMO

AIM: We aim to study the anti-apoptotic effect of microRNA-21-5p (miR-21-5p) in the oxidative stress-induced apoptosis of Schwann cells and the relevant mechanism in this research, laying a foundation for the treatment of peripheral neuropathy (PNP). METHODS AND MATERIALS: The oxidative stress model was established by using hydrogen peroxide (H2O2). ROS level were detected by DCFH-DA (2,7-Dichlorodi-hydrofluorescein diacetate). Western blot and fluorescence staining were used to detect the apoptosis and autophagy level. The miR-21-5p overexpression model was established by transfection of miR-21-5p mimics into RSC96 cells. Five groups of control group, H2O2 group, H2O2 + chloroquine (CQ) group, H2O2 + miR-21-5p mimics group, and H2O2 + miR-21-5p mimics+rapamycin (RAPA) group were included in our experiment. KEY FINDINGS: Compared with control group, miR-21-5p was decreased in H2O2-treated RSC96 cells, while autophagy and apoptosis were both promoted. The result revealed that apoptosis was probably triggered by activation of autophagy in H2O2-treated group. In order to verify the relationship between autophagy and apoptosis more accurately, we used CQ to inhibit autophagy. Compared with H2O2-treated group, autophagy and apoptosis were both weakened in H2O2 + CQ group. Subsequently, we found the antiapoptotic effect of miR-21-5p in this model, overexpression of miR-21-5p prevented cells from being damaged by oxidative stress, it induced the decrease of PTEN and the level of autophagy, leading to decreased level of apoptosis. SIGNIFICANCE: The identified relationship between miR-21-5p, apoptosis, and autophagy promotes us to find a new mechanism to improve the treatment for PNP.


Assuntos
Apoptose/genética , Autofagia/genética , MicroRNAs/genética , Estresse Oxidativo/genética , Animais , Linhagem Celular , Regulação da Expressão Gênica , Peróxido de Hidrogênio , PTEN Fosfo-Hidrolase/metabolismo , Doenças do Sistema Nervoso Periférico/genética , Doenças do Sistema Nervoso Periférico/terapia , Ratos , Espécies Reativas de Oxigênio/metabolismo , Células de Schwann/citologia
15.
Crit Rev Oncol Hematol ; 153: 103063, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32712519

RESUMO

Chronic lung disease has become a leading cause of death in recent years. Despite several attempts to discover and develop new therapeutic approaches, patients often suffer a poor quality of life, and are faced with an increased risk of developing lung cancer. Lung cancer often occurs as an end-stage after years of chronic lung disease. An increased understanding of the pathophysiology of chronic lung disease may be obtained from studying the role of autophagy in its initiation and progression. MicroRNAs (miRNAs) play a critical role in the modulation of autophagy, and their deregulation could be associated with the initiation and progression of several chronic lung diseases. Herein, we documented that up/down regulation of miRNAs can activate or inhibit autophagy in chronic lung diseases including lung cancer. Therefore, theses miRNAs could be a promising therapeutic tool for lung cancer specially in drug-resistance lung cancer cells.


Assuntos
Autofagia/genética , Pneumopatias , Neoplasias Pulmonares/genética , MicroRNAs/genética , Humanos , Pulmão , Qualidade de Vida
16.
PLoS One ; 15(7): e0236403, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32716961

RESUMO

Autophagy, a self-degradative physiological process, is critical for homeostasis maintenance and energy source balancing in response to various stresses, including nutrient deprivation. It is a highly conserved catabolic process in eukaryotes and is indispensable for cell survival as it involves degradation of unessential or excessive components and their subsequent recycling as building blocks for the synthesis of necessary molecules. Although the dysregulation of autophagy has been reported to broadly contribute to various diseases, including cancers and neurodegenerative diseases, the molecular mechanisms underlying the epigenetic regulation of autophagy are poorly elucidated. Here, we report that the level of lysine demethylase 3B (KDM3B) increases in nutrient-deprived HCT116 cells, a colorectal carcinoma cell line, resulting in transcriptional activation of the autophagy-inducing genes. KDM3B was found to enhance the transcription by demethylating H3K9me2 on the promoter of these genes. Furthermore, we observed that the depletion of KDM3B inhibited the autophagic flux in HCT116 cells. Collectively, these data suggested the critical role of KDM3B in the regulation of autophagy-related genes via H3K9me2 demethylation and induction of autophagy in nutrient-starved HCT116 cells.


Assuntos
Autofagia/genética , Histona Desmetilases com o Domínio Jumonji/metabolismo , Ativação Transcricional/genética , Aminoácidos/deficiência , Autofagia/efeitos dos fármacos , Epigênese Genética/efeitos dos fármacos , Células HCT116 , Células HEK293 , Histonas/metabolismo , Humanos , Regiões Promotoras Genéticas , Complexo de Endopeptidases do Proteassoma/metabolismo , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Proteólise/efeitos dos fármacos , Sirolimo/farmacologia , Ativação Transcricional/efeitos dos fármacos , Proteína com Valosina/metabolismo
17.
Int J Antimicrob Agents ; 56(3): 106078, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: covidwho-626866

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is having serious consequences on health and the economy worldwide. All evidence-based treatment strategies need to be considered to combat this new virus. Drugs need to be considered on scientific grounds of efficacy, safety and cost. Chloroquine (CQ) and hydroxychloroquine (HCQ) are old drugs used in the treatment of malaria. Moreover, their antiviral properties have been previously studied, including against coronaviruses, where evidence of efficacy has been found. In the current race against time triggered by the COVID-19 pandemic, the search for new antivirals is very important. However, consideration should be given to old drugs with known anti-coronavirus activity, such as CQ and HCQ. These could be integrated into current treatment strategies while novel treatments are awaited, also in light of the fact that they display an anticoagulant effect that facilitates the activity of low-molecular-weight heparin, aimed at preventing acute respiratory distress syndrome (ARDS)-associated thrombotic events. The safety of CQ and HCQ has been studied for over 50 years, however recently published data raise concerns for cardiac toxicity of CQ/HCQ in patients with COVID-19. This review also re-examines the real information provided by some of the published alarming reports, although concluding that cardiac toxicity should in any case be stringently monitored in patients receiving CQ/HCQ.


Assuntos
Antivirais/uso terapêutico , Betacoronavirus/efeitos dos fármacos , Cloroquina/uso terapêutico , Infecções por Coronavirus/tratamento farmacológico , Síndrome da Liberação de Citocina/prevenção & controle , Coagulação Intravascular Disseminada/prevenção & controle , Hidroxicloroquina/uso terapêutico , Pneumonia Viral/tratamento farmacológico , Anti-Inflamatórios/uso terapêutico , Anticoagulantes/uso terapêutico , Autofagia/efeitos dos fármacos , Autofagia/genética , Betacoronavirus/crescimento & desenvolvimento , Betacoronavirus/imunologia , Infecções por Coronavirus/patologia , Infecções por Coronavirus/virologia , Síndrome da Liberação de Citocina/virologia , Citocinas/antagonistas & inibidores , Citocinas/genética , Citocinas/imunologia , Coagulação Intravascular Disseminada/virologia , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/imunologia , Humanos , Fatores Imunológicos/uso terapêutico , Pandemias , Peptidil Dipeptidase A/genética , Peptidil Dipeptidase A/imunologia , Pneumonia Viral/patologia , Pneumonia Viral/virologia , Internalização do Vírus/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos
18.
Am J Chin Med ; 48(5): 1243-1261, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32668963

RESUMO

4-acetylantrocamol LT3 (4AALT3), a new ubiquinone from the mycelium of Antrodia cinnamomea (Polyporaceae), has been recently shown to possess anticancer activity. However, the detailed mechanisms of such action remain unclear. In this study, the molecular mechanisms of 4AALT3 on hepatocellular carcinoma cells (HCC) were investigated. Human hepatocellular carcinoma cell line HepG2 cells were treated with concentrations of 4AALT3. Cell viability, colony formation, and the underlying mechanisms were then analyzed by CCK-8, colony formation, qPCR, and Western blotting assays. We found that 4AALT3 significantly decreased cell viability and colony formation in a dose-dependent manner. Accordingly, 4AALT3 significantly decreased protein levels of cyclin B, E1, D1, and D3, thereby facilitating cell cycle arrest. In addition, 4AALT3 significantly suppressed the nuclear localization of Yes-associated protein (YAP)/transcriptional co-activator with PDZ-binding motif (TAZ), mammalian target of rapamycin (mTOR), and WNT/[Formula: see text]-catenin signaling pathways, all of which are well-known signaling pathways that contribute to the malignant properties of HCC. These effects are associated with activation of 5' AMP-activated protein kinase (AMPK) and autophagy. Our findings indicate that 4AALT3 exerts inhibitory effects on HepG2 cell growth via multiple signaling pathways and may be a potential agent for HCC therapy.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Antrodia/química , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Fatores de Transcrição/metabolismo , Ubiquinona/análogos & derivados , Ubiquinona/farmacologia , Proteínas Wnt/metabolismo , beta Catenina/metabolismo , Antineoplásicos Fitogênicos , Autofagia/efeitos dos fármacos , Autofagia/genética , Células Hep G2 , Humanos , Ubiquinona/isolamento & purificação
19.
DNA Cell Biol ; 39(9): 1532-1544, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32644844

RESUMO

Increasing evidence suggests that aberrant long noncoding (lnc) RNA expression plays a vital role in gastric cancer (GC) initiation and progression. Thus, we aimed to develop a lncRNA-based risk signature and nomogram to predict overall survival (OS) for patients with GC. Our primary cohort was composed of 341 patients with clinical and lncRNA expression data in The Cancer Genome Atlas stomach adenocarcinoma (TCGA STAD), the internal validation cohort was composed of 172 randomly assigned patients, and the external validation cohort was composed of 300 patients from GSE62254 dataset. A risk signature and nomogram were developed for the primary cohort and validated on the validation cohorts. Furthermore, gene set enrichment analysis (GSEA) was used to investigate the pathway enrichment for the risk signature. The expression patterns of several lncRNAs were also investigated in clinical samples from 10 GC patients. We identified and validated a 14-lncRNA signature highly associated with the OS of patients with GC, which performed well on evaluation with C-index, area under the curve, and calibration curves. In addition, univariate and multivariate Cox regression analyses indicated that the lncRNA signature was an independent predictive factor for GC patients. Therefore, a nomogram incorporating lncRNA signature and clinical factors was constructed to predict OS for patients with GC in primary cohort that suggested powerful predictive values for survival in the TCGA cohort and the other two validation cohorts. In addition, GSEA indicated that the identified lncRNAs may regulate the autophagy pathway, affecting tumorigenesis and prognosis of patients with GC. Experimental validation demonstrated that the expression of lncRNAs showed the same trend both in our clinical samples and STAD dataset. These results suggest that both risk signature and nomogram were effective prognostic indicators for patients with GC.


Assuntos
Adenocarcinoma/genética , Biomarcadores Tumorais/genética , RNA Longo não Codificante/genética , Neoplasias Gástricas/genética , Adenocarcinoma/patologia , Idoso , Autofagia/genética , Biomarcadores Tumorais/metabolismo , Carcinogênese/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , RNA Longo não Codificante/metabolismo , Neoplasias Gástricas/patologia , Análise de Sobrevida , Transcriptoma
20.
Life Sci ; 257: 118015, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32629000

RESUMO

BACKGROUND: Cardiovascular disease (CVD) is the leading cause of mortality worldwide. Cardiac fibrosis is the scarring process occurs commonly with CVDs impairing the function and structure of heart. Herein, we investigated the role of circPAN3 in the pathogenesis of cardiac fibrosis. METHODS: A rat myocardial infarction (MI) model was constructed to evaluate the role of circPAN3. Expression of circPAN3 in MI was determined, and si-circPAN3 was applied to verify its profibrotic effects. With an in vitro model, cardiac fibroblasts were stimulated by transforming growth factor beta 1 (TGFß1). Immunofluorescent staining was employed to assess the fibrosis-related markers, as well as autophagy activity. CCK-8 and transwell assays were performed to determine cell proliferation and migration. Luciferase reporter assay and RNA pull-down were subjected to verify the interaction of circPAN3/miR-221. The enrichment of FoxO3 on the promoter region of ATG7 was detected using CHIP assay. RESULTS: Elevated circPAN3 was found in rat MI heart tissue, of which knockdown attenuated cardiac fibrosis after MI. In an in vitro model exposing with TGFß1, increasing cell proliferation and migration were observed, whereas these effects were abolished by circPAN3 knockdown, as well as autophagy activity. miR-221 was identified as a target to be involved in circPAN3-mediated cardiac fibrosis after MI. miR-221 negatively regulated FoxO3, thus causing the inhibition of ATG7 transcription. The regulatory network of circPAN3/miR-221/FoxO3/ATG7 in cardiac fibrosis was further determined in vivo. CONCLUSION: circPAN3 exhibited profibrotic effects during autophagy-mediated cardiac fibrosis via miR-221/FoxO3/ATG7 axis, which may serve as potential biomarkers for cardiac fibrosis therapeutics.


Assuntos
Infarto do Miocárdio/genética , Infarto do Miocárdio/metabolismo , RNA Circular/genética , Animais , Autofagia/genética , Autofagia/fisiologia , Proteína 7 Relacionada à Autofagia/metabolismo , Proliferação de Células/genética , Modelos Animais de Doenças , Fibroblastos/metabolismo , Fibrose/metabolismo , Proteína Forkhead Box O3/metabolismo , Masculino , MicroRNAs/genética , MicroRNAs/metabolismo , Miocárdio/metabolismo , RNA Circular/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/genética
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