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1.
PLoS Comput Biol ; 16(8): e1008076, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32745094

RESUMO

We consider how a signalling system can act as an information hub by multiplexing information arising from multiple signals. We formally define multiplexing, mathematically characterise which systems can multiplex and how well they can do it. While the results of this paper are theoretical, to motivate the idea of multiplexing, we provide experimental evidence that tentatively suggests that the NF-κB transcription factor can multiplex information about changes in multiple signals. We believe that our theoretical results may resolve the apparent paradox of how a system like NF-κB that regulates cell fate and inflammatory signalling in response to diverse stimuli can appear to have the low information carrying capacity suggested by recent studies on scalar signals. In carrying out our study, we introduce new methods for the analysis of large, nonlinear stochastic dynamic models, and develop computational algorithms that facilitate the calculation of fundamental constructs of information theory such as Kullback-Leibler divergences and sensitivity matrices, and link these methods to a new theory about multiplexing information. We show that many current models such as those of the NF-κB system cannot multiplex effectively and provide models that overcome this limitation using post-transcriptional modifications.


Assuntos
Comunicação Celular/fisiologia , Modelos Biológicos , Transdução de Sinais/fisiologia , Algoritmos , Diferenciação Celular/fisiologia , Linhagem Celular Tumoral , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Regulação da Expressão Gênica , Humanos , Teoria da Informação , NF-kappa B/metabolismo , Análise de Célula Única , Processos Estocásticos
2.
Nature ; 583(7817): 620-624, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32669709

RESUMO

Approximately 75% of all breast cancers express the oestrogen and/or progesterone receptors. Endocrine therapy is usually effective in these hormone-receptor-positive tumours, but primary and acquired resistance limits its long-term benefit1,2. Here we show that in mouse models of hormone-receptor-positive breast cancer, periodic fasting or a fasting-mimicking diet3-5 enhances the activity of the endocrine therapeutics tamoxifen and fulvestrant by lowering circulating IGF1, insulin and leptin and by inhibiting AKT-mTOR signalling via upregulation of EGR1 and PTEN. When fulvestrant is combined with palbociclib (a cyclin-dependent kinase 4/6 inhibitor), adding periodic cycles of a fasting-mimicking diet promotes long-lasting tumour regression and reverts acquired resistance to drug treatment. Moreover, both fasting and a fasting-mimicking diet prevent tamoxifen-induced endometrial hyperplasia. In patients with hormone-receptor-positive breast cancer receiving oestrogen therapy, cycles of a fasting-mimicking diet cause metabolic changes analogous to those observed in mice, including reduced levels of insulin, leptin and IGF1, with the last two remaining low for extended periods. In mice, these long-lasting effects are associated with long-term anti-cancer activity. These results support further clinical studies of a fasting-mimicking diet as an adjuvant to oestrogen therapy in hormone-receptor-positive breast cancer.


Assuntos
Neoplasias da Mama/dietoterapia , Neoplasias da Mama/tratamento farmacológico , Dietoterapia/métodos , Jejum/fisiologia , Fulvestranto/uso terapêutico , Animais , Fatores Biológicos/sangue , Neoplasias da Mama/patologia , Dieta Saudável/métodos , Modelos Animais de Doenças , Progressão da Doença , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Feminino , Fulvestranto/administração & dosagem , Humanos , Insulina/sangue , Fator de Crescimento Insulin-Like I/metabolismo , Leptina/sangue , Células MCF-7 , Camundongos Endogâmicos NOD , Camundongos SCID , PTEN Fosfo-Hidrolase/metabolismo , Piperazinas/administração & dosagem , Piperazinas/uso terapêutico , Piridinas/administração & dosagem , Piridinas/uso terapêutico , Receptores Estrogênicos , Receptores de Progesterona , Tamoxifeno/efeitos adversos , Tamoxifeno/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto
3.
PLoS Biol ; 18(3): e3000666, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32203529

RESUMO

Ataxia-telangiectasia mutated (ATM) is an apical kinase of the DNA damage response following DNA double-strand breaks (DSBs); however, the mechanisms of ATM activation are not completely understood. Long noncoding RNAs (lncRNAs) are a class of regulatory molecules whose significant roles in DNA damage response have started to emerge. However, how lncRNA regulates ATM activity remains unknown. Here, we identify an inhibitor of ATM activation, lncRNA HITT (HIF-1α inhibitor at translation level). Mechanistically, HITT directly interacts with ATM at the HEAT repeat domain, blocking MRE11-RAD50-NBS1 complex-dependent ATM recruitment, leading to restrained homologous recombination repair and enhanced chemosensitization. Following DSBs, HITT is elevated mainly by the activation of Early Growth Response 1 (EGR1), resulting in retarded and restricted ATM activation. A reverse association between HITT and ATM activity was also detected in human colon cancer tissues. Furthermore, HITTs sensitize DNA damaging agent-induced cell death both in vitro and in vivo. These findings connect lncRNA directly to ATM activity regulation and reveal potential roles for HITT in sensitizing cancers to genotoxic treatment.


Assuntos
Antineoplásicos/farmacologia , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Dano ao DNA , RNA Longo não Codificante/metabolismo , Reparo de DNA por Recombinação/genética , Hidrolases Anidrido Ácido/metabolismo , Animais , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Proteínas Mutadas de Ataxia Telangiectasia/antagonistas & inibidores , Proteínas Mutadas de Ataxia Telangiectasia/genética , Sítios de Ligação , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Quebras de DNA de Cadeia Dupla/efeitos dos fármacos , Proteínas de Ligação a DNA/metabolismo , Proteína 1 de Resposta de Crescimento Precoce/genética , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Células HCT116 , Células HeLa , Humanos , Proteína Homóloga a MRE11/metabolismo , Camundongos , Camundongos Nus , Neoplasias/tratamento farmacológico , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologia , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Fosforilação , Ligação Proteica , RNA Longo não Codificante/genética , Transcrição Genética/efeitos dos fármacos
4.
Int J Mol Sci ; 21(4)2020 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-32102332

RESUMO

In-stent restenosis is a serious concern for patients treated through the stenting procedure, although this can be solved using drug-eluting stents and/or drug-eluting balloon catheters. However, the chemical agents released from the drug-eluting layer for inhibiting smooth muscle cell (SMC) migration are inevitably associated with damage to vascular endothelial cell (ECs). The present in vitro study used a distinct strategy, in which a smart gene (phEGR1-PKCδ, an engineered plasmid consists of an SMC-specific promoter (human early growth response 1, hEGR1 promoter) ligated with a gene encoding apoptosis-inducing protein (protein kinase C-delta, PKCδ) was incorporated into a novel gene vehicle (Au cluster-incorporated polyethylenimine/carboxymethyl hexanoyl chitosan, PEI-Au/CHC) to form the PEI-Au/CHC/phEGR1-PKCδ complex, which was proposed for the selective inhibition of SMC proliferation. It was found that the cell viability of SMCs receiving the PEI-Au/CHC/phEGR1-PKCδ complex under simulated inflammation conditions was significantly lower than that of the ECs receiving the same treatment. In addition, the PEI-Au/CHC/phEGR1-PKCδ complex did not demonstrate an inhibitory effect on EC proliferation and migration under simulated inflammation conditions. Finally, the PEI-Au/CHC/phEGR1-PKCδ complexes coated onto a balloon catheter used in percutaneous transluminal coronary angioplasty (PTCA) could be transferred to both the ECs and the SMC layer of Sprague Dawley (SD) rat aortas ex vivo. These preliminary in vitro results suggest that the newly developed approach proposed in the present study might be a potential treatment for reducing the incidence rate of in-stent restenosis and late thrombosis in the future.


Assuntos
Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Terapia Genética/métodos , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Proteína Quinase C-delta/metabolismo , Animais , Aorta/citologia , Aorta/metabolismo , Apoptose/genética , Sobrevivência Celular/genética , Reestenose Coronária/genética , Reestenose Coronária/terapia , Portadores de Fármacos/química , Stents Farmacológicos , Proteína 1 de Resposta de Crescimento Precoce/genética , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Engenharia Genética , Microscopia de Fluorescência , Músculo Liso Vascular/citologia , Miócitos de Músculo Liso/citologia , Nanoestruturas/química , Proteína Quinase C-delta/genética , Ratos Sprague-Dawley
5.
Mol Immunol ; 120: 61-66, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32078859

RESUMO

Myocardial infarction (MI) or heart attack is a deadly event with high prevalence. In the present study, we investigated the effects of the polypeptide copolymer glatiramer acetate (GA) in H9c2 rat cardiomyocytes exposed to oxygen-glucose deprivation/reperfusion injury. Immediately following MI, an acute inflammatory response is triggered that causes activation of various proinflammatory cytokines, infiltration of immune cells, and neovascularization. This response is largely mediated by some genes such as TNF-α, IL-6, ICAM-1, and VEGF. Additionally, the rapid influx of oxidants, such as reactive oxygen species (ROS), leads to a harmful state of oxidative stress. Here, we found that GA could reduce OGD/R-induced inflammation and oxidative stress by inhibiting the expression of TNF-α, IL-6, ICAM-1, and VEGF, and suppressing the production of ROS via reduced NADPH oxidase 1 (NOX1) expression. To elucidate the pathways involved in these promising results, we took a close look at the impact of the endothelial growth response-1 (Egr-1), a transcriptional factor recognized as a mediator of MI-related inflammation and cellular injury. Using siRNA for Egr-1, we found that GA could reduce the expression of ICAM-1 and VEGF by inhibiting Egr-1 expression. Together, our findings indicate a novel therapeutic potential of GA in the treatment of MI.


Assuntos
Cardiotônicos/farmacologia , Proteína 1 de Resposta de Crescimento Precoce/antagonistas & inibidores , Acetato de Glatiramer/farmacologia , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Animais , Linhagem Celular , Proteína 1 de Resposta de Crescimento Precoce/genética , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Glucose/metabolismo , Mediadores da Inflamação/antagonistas & inibidores , Mediadores da Inflamação/metabolismo , Infarto do Miocárdio/tratamento farmacológico , Infarto do Miocárdio/genética , Infarto do Miocárdio/metabolismo , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Estresse Oxidativo/efeitos dos fármacos , Oxigênio/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Espécies Reativas de Oxigênio/metabolismo
6.
Basic Res Cardiol ; 115(2): 9, 2020 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-31900593

RESUMO

Ventricular arrhythmia is the most common cause of sudden cardiac death in patients with myocardial infarction (MI). Fibroblast growth factor 21 (FGF21) has been shown to play an important role in cardiovascular and metabolic diseases. However, the effects of FGF21 on ventricular arrhythmias following MI have not been addressed yet. The present study was conducted to investigate the pharmacological action of FGF21 on ventricular arrhythmias after MI. Adult male mice were administrated with or without recombinant human basic FGF21 (rhbFGF21), and the susceptibility to arrhythmias was assessed by programmed electrical stimulation and optical mapping techniques. Here, we found that rhbFGF21 administration reduced the occurrence of ventricular tachycardia (VT), improved epicardial conduction velocity and shorted action potential duration at 90% (APD90) in infarcted mouse hearts. Mechanistically, FGF21 may improve cardiac electrophysiological remodeling as characterized by the decrease of INa and IK1 current density in border zone of infarcted mouse hearts. Consistently, in vitro study also demonstrated that FGF21 may rescue oxidant stress-induced dysfunction of INa and IK1 currents in cultured ventricular myocytes. We further found that oxidant stress-induced down-regulation of early growth response protein 1 (EGR1) contributed to INa and IK1 reduction in post-infarcted hearts, and FGF21 may recruit EGR1 into the SCN5A and KCNJ2 promoter regions to up-regulate NaV1.5 and Kir2.1 expression at transcriptional level. Moreover, miR-143 was identified as upstream of EGR1 and mediated FGF21-induced EGR1 up-regulation in cardiomyocytes. Collectively, rhbFGF21 administration effectively suppressed ventricular arrhythmias in post-infarcted hearts by regulating miR-143-EGR1-NaV1.5/Kir2.1 axis, which provides novel therapeutic strategies for ischemic arrhythmias in clinics.


Assuntos
Antiarrítmicos/administração & dosagem , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Fatores de Crescimento de Fibroblastos/administração & dosagem , Sistema de Condução Cardíaco/efeitos dos fármacos , Frequência Cardíaca/efeitos dos fármacos , MicroRNAs/metabolismo , Infarto do Miocárdio/tratamento farmacológico , Miocárdio/metabolismo , Taquicardia Ventricular/prevenção & controle , Potenciais de Ação/efeitos dos fármacos , Animais , Células Cultivadas , Modelos Animais de Doenças , Proteína 1 de Resposta de Crescimento Precoce/genética , Sistema de Condução Cardíaco/metabolismo , Sistema de Condução Cardíaco/fisiopatologia , Masculino , Camundongos Endogâmicos C57BL , MicroRNAs/genética , Infarto do Miocárdio/genética , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/fisiopatologia , Miocárdio/patologia , Canal de Sódio Disparado por Voltagem NAV1.5/genética , Canal de Sódio Disparado por Voltagem NAV1.5/metabolismo , Canais de Potássio Corretores do Fluxo de Internalização/genética , Canais de Potássio Corretores do Fluxo de Internalização/metabolismo , Proteínas Recombinantes/administração & dosagem , Transdução de Sinais , Taquicardia Ventricular/genética , Taquicardia Ventricular/metabolismo , Taquicardia Ventricular/fisiopatologia
7.
Nat Immunol ; 21(3): 287-297, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31932812

RESUMO

Cancer cells subvert immune surveillance through inhibition of T cell effector function. Elucidation of the mechanism of T cell dysfunction is therefore central to cancer immunotherapy. Here, we report that dual specificity phosphatase 2 (DUSP2; also known as phosphatase of activated cells 1, PAC1) acts as an immune checkpoint in T cell antitumor immunity. PAC1 is selectively upregulated in exhausted tumor-infiltrating lymphocytes and is associated with poor prognosis of patients with cancer. PAC1hi effector T cells lose their proliferative and effector capacities and convert into exhausted T cells. Deletion of PAC1 enhances immune responses and reduces cancer susceptibility in mice. Through activation of EGR1, excessive reactive oxygen species in the tumor microenvironment induce expression of PAC1, which recruits the Mi-2ß nucleosome-remodeling and histone-deacetylase complex, eventually leading to chromatin remodeling of effector T cells. Our study demonstrates that PAC1 is an epigenetic immune regulator and highlights the importance of targeting PAC1 in cancer immunotherapy.


Assuntos
Fosfatase 2 de Especificidade Dupla/imunologia , Neoplasias/imunologia , Linfócitos T/imunologia , Animais , Cromatina/genética , Cromatina/metabolismo , Fosfatase 2 de Especificidade Dupla/deficiência , Fosfatase 2 de Especificidade Dupla/genética , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Feminino , Humanos , Ativação Linfocitária , Linfócitos do Interstício Tumoral/imunologia , Masculino , Complexo Mi-2 de Remodelação de Nucleossomo e Desacetilase/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Camundongos Knockout , Camundongos SCID , Neoplasias/genética , Neoplasias/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Microambiente Tumoral/genética , Microambiente Tumoral/imunologia , Regulação para Cima
8.
Int J Mol Sci ; 21(1)2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31906413

RESUMO

Muscle invasive bladder carcinoma is a highly malignant cancer with a high mortality rate, due to its tendency to metastasize. The tyrosine kinase recepteur d'origine nantais (RON) promotes bladder carcinoma metastasis. Lysophosphatidic acid (LPA) is a phospholipid derivative, which acts as a signaling molecule to activate three high affinity G-protein coupled receptors, LPA1, LPA2, and LPA3. This in turn leads to cell proliferation and contributes to oncogenesis. However, little is known about the effects of LPA on invasive bladder cancer (IBC). In this study, we discovered that LPA upregulated RON expression, which in turn promoted cell invasion in bladder cancer T24 cells. As expected, we found that the LPA receptor was essential for the LPA induced increase in RON expression. More interestingly, we discovered that LPA induced RON expression via the MAPK (ERK1/2, JNK1/2), Egr-1, AP-1, and NF-κB signaling axes. These results provide experimental evidence and novel insights regarding bladder malignancy metastasis, which could be helpful for developing new therapeutic strategies for IBC treatment.


Assuntos
Movimento Celular/efeitos dos fármacos , Lisofosfolipídeos/farmacologia , Receptores Proteína Tirosina Quinases/metabolismo , Transdução de Sinais/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos , Neoplasias da Bexiga Urinária/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proteína 1 de Resposta de Crescimento Precoce/antagonistas & inibidores , Proteína 1 de Resposta de Crescimento Precoce/genética , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Humanos , NF-kappa B/metabolismo , Isoformas de Proteínas/antagonistas & inibidores , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Receptores Proteína Tirosina Quinases/genética , Receptores de Ácidos Lisofosfatídicos/antagonistas & inibidores , Receptores de Ácidos Lisofosfatídicos/genética , Receptores de Ácidos Lisofosfatídicos/metabolismo , Fator de Transcrição AP-1/antagonistas & inibidores , Fator de Transcrição AP-1/metabolismo , Neoplasias da Bexiga Urinária/metabolismo
9.
Int J Cancer ; 146(8): 2218-2228, 2020 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-31443114

RESUMO

Glioblastoma (GBM) is one of the most aggressive primary brain tumors with frequent recurrences following the standard methods of treatment-temozolomide (TMZ), ionizing radiation and surgical resection. The objective of our study was to investigate GBM resistance mediated via MMP14 (matrix metalloproteinase 14). We used multiple PDX GBM models and established glioma cell lines to characterize expression and subcellular localization of MMP14 after TMZ treatment. We performed a Kiloplex ELISA-based array to evaluate changes in cellular proteins induced by MMP14 expression and translocation. Lastly, we conducted functional and mechanistic studies to elucidate the role of DLL4 (delta-like canonical notch ligand 4) in regulation of glioma stemness, particularly in the context of its relationship to MMP14. We detected that TMZ treatment promotes nuclear translocation of MMP14 followed by extracellular release of DLL4. DLL4 in turn stimulates cleavage of Notch3, its nuclear translocation and induction of sphering capacity and stemness.


Assuntos
Neoplasias Encefálicas/tratamento farmacológico , Glioblastoma/tratamento farmacológico , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Metaloproteinase 14 da Matriz/metabolismo , Proteínas de Membrana/metabolismo , Células-Tronco Neoplásicas/efeitos dos fármacos , Receptor Notch3/metabolismo , Temozolomida/farmacologia , Animais , Biomarcadores Tumorais/biossíntese , Biomarcadores Tumorais/metabolismo , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Fatores de Crescimento de Fibroblastos/metabolismo , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Metaloproteinase 14 da Matriz/biossíntese , Camundongos , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
10.
Biomed Pharmacother ; 123: 109616, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31881485

RESUMO

Breast cancer (BC) is a major contributor of cancer-associated mortality in women. It is essential to find new therapeutic targets and drugs. Polyrhachis vicina Rogers is one of the Traditional Chinese Medicine (TCM). Our previous studies have shown an active fraction of Polyrhachis vicina Rogers (AFPR) has significant anti-inflammatory activity, suggesting its anti-cancer effect. Here, we aimed to explore the inhibitory effects of AFPR on BC and reveal its mechanism. The effects of AFPR on BC were examined by cell proliferation assay, wound healing assay, invasion assay and xenograft assay. Microarray sequencing, qRT-PCR, Western blot, chromatin immunoprecipitation assay and luciferase reporter assay were performed to investigate the regulation of AFPR on related genes and underlying mechanisms. As a result, AFPR suppressed BC cell growth, migration and invasion and inhibited tumor growth. LncRNA NKILA was most prominently upregulated in AFPR-treated MCF7 cells. AFPR inactivated NF-κB signaling pathway via regulating NKILA. Furthermore, AFPR regulated the expression of NKILA by inhibiting its transcript suppressor EGR1. This study firstly indicated that AFPR was a potential inhibitor of BC development via regulating EGR1/NKILA/NF-κB axis.


Assuntos
Formigas/química , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , NF-kappa B/metabolismo , RNA Longo não Codificante/metabolismo , Animais , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Movimento Celular/efeitos dos fármacos , Fracionamento Químico , Proteína 1 de Resposta de Crescimento Precoce/genética , Feminino , Humanos , Células MCF-7 , Masculino , Medicina Tradicional Chinesa , Camundongos Nus , NF-kappa B/genética , Invasividade Neoplásica , Neoplasias Experimentais , RNA Longo não Codificante/genética , Regulação para Cima
11.
Virology ; 539: 121-128, 2020 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-31733451

RESUMO

Venezuelan equine encephalitis virus (VEEV) is a neurotropic virus that causes significant disease in both humans and equines. Here we characterized the impact of VEEV on signaling pathways regulating cell death in human primary astrocytes. VEEV productively infected primary astrocytes and caused an upregulation of early growth response 1 (EGR1) gene expression at 9 and 18 h post infection. EGR1 induction was dependent on extracellular signal-regulated kinase1/2 (ERK1/2) and protein kinase R (PKR)-like endoplasmic reticulum kinase (PERK), but not on p38 mitogen activated protein kinase (MAPK) or phosphoinositide 3-kinase (PI3K) signaling. Knockdown of EGR1 significantly reduced VEEV-induced apoptosis and impacted viral replication. Knockdown of ERK1/2 or PERK significantly reduced EGR1 gene expression, dramatically reduced viral replication, and increased cell survival as well as rescued cells from VEEV-induced apoptosis. These data indicate that EGR1 activation and subsequent cell death are regulated through ERK and PERK pathways in VEEV infected primary astrocytes.


Assuntos
Morte Celular , Proteína 1 de Resposta de Crescimento Precoce/genética , Vírus da Encefalite Equina Venezuelana/fisiologia , Encefalomielite Equina Venezuelana/virologia , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , eIF-2 Quinase/metabolismo , Apoptose , Astrócitos/metabolismo , Astrócitos/patologia , Astrócitos/virologia , Sobrevivência Celular , Células Cultivadas , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Vírus da Encefalite Equina Venezuelana/patogenicidade , Encefalomielite Equina Venezuelana/metabolismo , Encefalomielite Equina Venezuelana/patologia , Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Proteína Quinase 1 Ativada por Mitógeno/genética , Proteína Quinase 3 Ativada por Mitógeno/genética , Transdução de Sinais , Replicação Viral , eIF-2 Quinase/genética
12.
Toxicol Lett ; 318: 12-21, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31622651

RESUMO

Maternal smoking during pregnancy and lactation is associated with increased fat mass in the offspring, but the mechanism by which this occurs is not fully understood. Our study focused on the relationships among maternal nicotine exposure, adipose angiogenesis and adipose tissue function in female offspring. Pregnant rats were randomly assigned to nicotine or control groups. Microvascular density, lipid metabolism and α7nAChR-Egr1-FGF2 signaling pathway genes/proteins were tested in 4-, 12- and 26-week female offspring. In vitro, nicotine concentration- and time-response experiments were conducted in 3T3-L1. Lipid metabolism and α7nAChR-Egr1-FGF2 signaling pathway genes/proteins were tested. The conditioned media of differentiated 3T3-L1 treated with nicotine were used to observe tube formation in human umbilical vein endothelial cells (HUVECs). Nicotine-exposed females presented higher adipose microvascular density. The gene expression of α7nAChR, Egr1 and FGF2 was significantly increased in gonadal white adipose tissue (gWAT) and inguinal subcutaneous WAT (igSWAT) of nicotine-exposed females at 4 weeks of age. The protein expression of α7nAChR, Egr1 and FGF2 was increased in gWAT and igSWAT of nicotine-exposed females at 4 weeks of age, and increased in gWAT at 26 weeks. In vitro, nicotine increased the expression of lipid metabolism and α7nAChR-Egr1-FGF2 signaling pathway genes/proteins in a concentration- and time-dependent manner. In the tube formation experiment, adipocytes affected by nicotine promoted HUVEC angiogenesis. Therefore, maternal nicotine exposure promoted the early angiogenesis of adipose tissue via the α7nAChR-Egr1-FGF2 signaling pathway, and this angiogenesis mechanism was associated with increased adipogenesis in adipose tissue of female offspring.


Assuntos
Adipócitos/efeitos dos fármacos , Tecido Adiposo Branco/irrigação sanguínea , Neovascularização Fisiológica/efeitos dos fármacos , Nicotina/toxicidade , Agonistas Nicotínicos/toxicidade , Efeitos Tardios da Exposição Pré-Natal , Células 3T3-L1 , Adipócitos/metabolismo , Animais , Proteína 1 de Resposta de Crescimento Precoce/genética , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Feminino , Fator 2 de Crescimento de Fibroblastos/genética , Fator 2 de Crescimento de Fibroblastos/metabolismo , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Exposição Materna , Camundongos , Gravidez , Ratos Wistar , Transdução de Sinais/efeitos dos fármacos , Receptor Nicotínico de Acetilcolina alfa7/genética , Receptor Nicotínico de Acetilcolina alfa7/metabolismo
13.
J Orthop Res ; 38(1): 173-181, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31692087

RESUMO

Tendon cells exist in a dense extracellular matrix and mechanical loading is important for the strength development of this matrix. We therefore use a three-dimensional (3D) culture system for tendon formation in vitro. The objectives of this study were to elucidate the temporal expression of tendon-related genes during the formation of artificial tendons in vitro and to investigate if early growth response-1 (EGR1), EGR2, FOS, and cyclooxygenase-1 and -2 (PTGS1 and PTGS2) are sensitive to mechanical loading. First, we studied messenger RNA (mRNA) levels of several tendon-related genes during formation of tendon constructs. Second, we studied the mRNA levels of, for example, EGR1 and EGR2 after different degrees of loading; dynamic physiologic-range loading (2.5% strain), dynamic overloading (approximately 10% strain), or tension release. The gene expression for tendon-related genes (i.e., EGR2, MKX, TNMD, COL3A1) increased with time after seeding into this 3D model. EGR1, EGR2, FOS, PTGS1, and PTGS2 did not respond to physiologic-range loading. But overloading (and tension release) lead to elevated levels of EGR1 and EGR2 (p ≤ 0.006). FOS and PTGS2 were increased after overloading (both p < 0.007) but not after tension release (p = 0.06 and 0.08). In conclusion, the expression of tendon-related genes increases during the formation of artificial tendons in vitro, including EGR2. Furthermore, the gene expression of EGR1 and EGR2 in human tendon cells appear to be sensitive to overloading and unloading but did not respond to the single episode of physiologic-range loading. These findings could be helpful for the understanding of tendon tensional homeostasis. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 38:173-181, 2020.


Assuntos
Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Proteína 2 de Resposta de Crescimento Precoce/metabolismo , Tenócitos/metabolismo , Engenharia Tecidual , Expressão Gênica , Humanos , Cultura Primária de Células , Suporte de Carga
14.
Food Chem Toxicol ; 136: 111083, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31887396

RESUMO

Prenatal ethanol exposure induces developmental toxicities of multiple organs in offspring. Here, we investigate the effects of prenatal ethanol exposure on bone mass in postnatal offspring and explore its intrauterine programming mechanism. We found that prenatal ethanol exposure could induce bone dysplasia in fetuses and postnatal osteopenia in female offspring, accompanied by the sustained activation of the local renin-angiotensin systems (RAS) and inhibition of bone formation. Additionally, we also found that histone 3 lysine 9 acetylation (H3K9ac) and H3K27ac levels in the promoter region of angiotensin-converting enzyme (ACE) were increased in female offspring exposed to ethanol during pregnancy. In vitro, ethanol suppressed the formation of mineralized nodules and osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs), which was blocked by enalapril. Furthermore, ethanol promoted the expression and nuclear translocation of early growth response factor 1 (Egr1), which participated in the promotion of histone acetylation of ACE and subsequent RAS activation, by recruiting p300 and binding to the ACE promoter region directly. These findings indicate that the sustained activation of the local RAS might participate in bone dysplasia in fetus and postnatal osteopenia in the female offspring, while the Egr1/p300/ACE signal might be a key promoter of the sustained activation of the local RAS of the long bone.


Assuntos
Doenças Ósseas Metabólicas/metabolismo , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Etanol/efeitos adversos , Exposição Materna/efeitos adversos , Peptidil Dipeptidase A/metabolismo , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Fatores de Transcrição de p300-CBP/metabolismo , Acetilação , Animais , Doenças Ósseas Metabólicas/etiologia , Doenças Ósseas Metabólicas/genética , Doenças Ósseas Metabólicas/fisiopatologia , Proteína 1 de Resposta de Crescimento Precoce/genética , Feminino , Histonas/genética , Histonas/metabolismo , Humanos , Masculino , Osteogênese , Peptidil Dipeptidase A/genética , Gravidez , Efeitos Tardios da Exposição Pré-Natal/etiologia , Efeitos Tardios da Exposição Pré-Natal/genética , Efeitos Tardios da Exposição Pré-Natal/fisiopatologia , Ratos , Ratos Wistar , Fatores Sexuais , Fatores de Transcrição de p300-CBP/genética
15.
Basic Res Cardiol ; 115(1): 3, 2019 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-31823016

RESUMO

Despite improved treatment options myocardial infarction (MI) is still a leading cause of mortality and morbidity worldwide. Remote ischemic preconditioning (RIPC) is a mechanistic process that reduces myocardial infarction size and protects against ischemia reperfusion (I/R) injury. The zinc finger transcription factor early growth response-1 (Egr-1) is integral to the biological response to I/R, as its upregulation mediates the increased expression of inflammatory and prothrombotic processes. We aimed to determine the association and/or role of Egr-1 expression with the molecular mechanisms controlling the cardioprotective effects of RIPC. This study used H9C2 cells in vitro and a rat model of cardiac ischemia reperfusion (I/R) injury. We silenced Egr-1 with DNAzyme (ED5) in vitro and in vivo, before three cycles of RIPC consisting of alternating 5 min hypoxia and normoxia in cells or hind-limb ligation and release in the rat, followed by hypoxic challenge in vitro and I/R injury in vivo. Post-procedure, ED5 administration led to a significant increase in infarct size compared to controls (65.90 ± 2.38% vs. 41.00 ± 2.83%, p < 0.0001) following administration prior to RIPC in vivo, concurrent with decreased plasma IL-6 levels (118.30 ± 4.30 pg/ml vs. 130.50 ± 1.29 pg/ml, p < 0.05), downregulation of the cardioprotective JAK-STAT pathway, and elevated myocardial endothelial dysfunction. In vitro, ED5 administration abrogated IL-6 mRNA expression in H9C2 cells subjected to RIPC (0.95 ± 0.20 vs. 6.08 ± 1.40-fold relative to the control group, p < 0.05), resulting in increase in apoptosis (4.76 ± 0.70% vs. 2.23 ± 0.34%, p < 0.05) and loss of mitochondrial membrane potential (0.57 ± 0.11% vs. 1.0 ± 0.14%-fold relative to control, p < 0.05) in recipient cells receiving preconditioned media from the DNAzyme treated donor cells. This study suggests that Egr-1 functions as a master regulator of remote preconditioning inducing a protective effect against myocardial I/R injury through IL-6-dependent JAK-STAT signaling.


Assuntos
Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Interleucina-6/metabolismo , Precondicionamento Isquêmico Miocárdico , Janus Quinases/metabolismo , Fatores de Transcrição STAT/metabolismo , Animais , Linhagem Celular , Ratos
16.
PLoS Pathog ; 15(11): e1007854, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31725809

RESUMO

Reactivation of latent Human Cytomegalovirus (HCMV) in CD34+ hematopoietic progenitor cells (HPCs) is closely linked to hematopoiesis. Viral latency requires maintenance of the progenitor cell quiescence, while reactivation initiates following mobilization of HPCs to the periphery and differentiation into CD14+ macrophages. Early growth response gene 1 (EGR-1) is a transcription factor activated by Epidermal growth factor receptor (EGFR) signaling that is essential for the maintenance of CD34+ HPC self-renewal in the bone marrow niche. Down-regulation of EGR-1 results in mobilization and differentiation of CD34+ HPC from the bone marrow to the periphery. In the current study we demonstrate that the transcription factor EGR-1 is directly targeted for down-regulation by HCMV miR-US22 that results in decreased proliferation of CD34+ HPCs and a decrease in total hematopoietic colony formation. We also show that an HCMV miR-US22 mutant fails to reactivate in CD34+ HPCs, indicating that expression of EGR-1 inhibits viral reactivation. Since EGR-1 promotes CD34+ HPC self-renewal in the bone marrow niche, HCMV miR-US22 down-regulation of EGR-1 is a necessary step to block HPC self-renewal and proliferation to induce a cellular differentiation pathway necessary to promote reactivation of virus.


Assuntos
Proliferação de Células , Infecções por Citomegalovirus/virologia , Citomegalovirus/fisiologia , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Células-Tronco Hematopoéticas/citologia , MicroRNAs/genética , Ativação Viral , Diferenciação Celular , Células Cultivadas , Proteína 1 de Resposta de Crescimento Precoce/genética , Hematopoese , Células-Tronco Hematopoéticas/virologia , Interações Hospedeiro-Patógeno , Humanos , Transdução de Sinais
17.
PLoS Pathog ; 15(11): e1008037, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31725811

RESUMO

Sustained phosphotinositide3-kinase (PI3K) signaling is critical to the maintenance of alpha and beta herpesvirus latency. We have previously shown that the beta-herpesvirus, human cytomegalovirus (CMV), regulates epidermal growth factor receptor (EGFR), upstream of PI3K, to control states of latency and reactivation. How signaling downstream of EGFR is regulated and how this impacts CMV infection and latency is not fully understood. We demonstrate that CMV downregulates EGFR early in the productive infection, which blunts the activation of EGFR and its downstream pathways in response to stimuli. However, CMV infection sustains basal levels of EGFR and downstream pathway activity in the context of latency in CD34+ hematopoietic progenitor cells (HPCs). Inhibition of MEK/ERK, STAT or PI3K/AKT pathways downstream of EGFR increases viral reactivation from latently infected CD34+ HPCs, defining a role for these pathways in latency. We hypothesized that CMV modulation of EGFR signaling might impact viral transcription important to latency. Indeed, EGF-stimulation increased expression of the UL138 latency gene, but not immediate early or early viral genes, suggesting that EGFR signaling promotes latent gene expression. The early growth response-1 (EGR1) transcription factor is induced downstream of EGFR signaling through the MEK/ERK pathway and is important for the maintenance of hematopoietic stemness. We demonstrate that EGR1 binds the viral genome upstream of UL138 and is sufficient to promote UL138 expression. Further, disruption of EGR1 binding upstream of UL138 prevents the establishment of latency in CD34+ HPCs. Our results indicate a model whereby UL138 modulation of EGFR signaling feeds back to promote UL138 gene expression and suppression of replication for latency. By this mechanism, the virus has hardwired itself into host cell biology to sense and respond to changes in homeostatic host cell signaling.


Assuntos
Infecções por Citomegalovirus/virologia , Citomegalovirus/fisiologia , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Regulação Viral da Expressão Gênica , Interações Hospedeiro-Patógeno , Proteínas Virais/metabolismo , Replicação Viral , Infecções por Citomegalovirus/genética , Infecções por Citomegalovirus/metabolismo , Proteína 1 de Resposta de Crescimento Precoce/genética , Genoma Viral , Células-Tronco Hematopoéticas/metabolismo , Células-Tronco Hematopoéticas/patologia , Células-Tronco Hematopoéticas/virologia , Humanos , Proteínas Virais/genética , Latência Viral
18.
Proc Natl Acad Sci U S A ; 116(47): 23743-23752, 2019 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-31685635

RESUMO

Epidemiological studies show that maternal diabetes is associated with an increased risk of autism spectrum disorders (ASDs), although the detailed mechanisms remain unclear. The present study aims to investigate the potential effect of maternal diabetes on autism-like behavior in offspring. The results of in vitro study showed that transient hyperglycemia induces persistent reactive oxygen species (ROS) generation with suppressed superoxide dismutase 2 (SOD2) expression. Additionally, we found that SOD2 suppression is due to oxidative stress-mediated histone methylation and the subsequent dissociation of early growth response 1 (Egr1) on the SOD2 promoter. Furthermore, in vivo rat experiments showed that maternal diabetes induces SOD2 suppression in the amygdala, resulting in autism-like behavior in offspring. SOD2 overexpression restores, while SOD2 knockdown mimics, this effect, indicating that oxidative stress and SOD2 expression play important roles in maternal diabetes-induced autism-like behavior in offspring, while prenatal and postnatal treatment using antioxidants permeable to the blood-brain barrier partly ameliorated this effect. We conclude that maternal diabetes induces autism-like behavior through hyperglycemia-mediated persistent oxidative stress and SOD2 suppression. Here we report a potential mechanism for maternal diabetes-induced ASD.


Assuntos
Transtorno Autístico/etiologia , Diabetes Mellitus Experimental/complicações , Diabetes Gestacional/metabolismo , Hiperglicemia/complicações , Estresse Oxidativo , Tonsila do Cerebelo/enzimologia , Animais , Transtorno Autístico/metabolismo , Barreira Hematoencefálica , Diabetes Mellitus Experimental/metabolismo , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Feminino , Técnicas de Silenciamento de Genes , Histonas/metabolismo , Metilação , Gravidez , Regiões Promotoras Genéticas , Ratos , Espécies Reativas de Oxigênio/metabolismo , Resveratrol/administração & dosagem , Resveratrol/farmacocinética , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo
19.
Int J Mol Sci ; 20(20)2019 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-31635309

RESUMO

Epidermal growth factor (EGF) is a member of the EGF-like ligands family, which plays a vital role in cell proliferation, differentiation, and folliculogenesis through binding with EGF receptors, including ErbB1 (EGFR/HER1), ErbB2 (HER2), ErbB3 (HER3), and ErbB4 (HER4). In mammals, many functional roles of EGF have been reported in the ovaries and breasts. However, little is known about the functions of EGF in the pituitary, especially in teleost. In this study, using grass carp pituitary cells as the model, we try to examine the direct pituitary actions of EGF in teleost. Firstly, transcriptomic analysis showed that 599 different expressed genes (DEGs) between the control and EGF-treatment group were mainly involved in cell proliferation, cell migration, signal transduction, and transcriptional regulation. Then, we further confirmed that EGF could significantly induce UTS1, EGR1, and MMP13 mRNA expression in a time-and dose-dependent manner. The stimulatory actions of EGF on UTS1 and EGR1 mRNA expression were mediated by the MEK1/2/ERK1/2 and PI3K/AKT/mTOR pathways coupled with both ErbB1 and ErbB2 in grass carp pituitary cells. The receptor specificity and signal transductions for the corresponding responses on MMP13 mRNA expression were also similar, except that the ErbB2 and PI3K/AKT/mTOR pathway were not involved. As we know, MMP13 could release EGF from HB-EGF. Interestingly, our data also showed that the MMPs inhibitor BB94 could suppress EGF-induced UTS1 and EGR1 mRNA expression. These results, taken together, suggest that the stimulatory actions of EGF on UTS1 and EGR1 mRNA expression could be enhanced by EGF-induced MMP13 expression in the pituitary.


Assuntos
Fator de Crescimento Epidérmico/metabolismo , Receptores ErbB/metabolismo , Hipófise/metabolismo , Transdução de Sinais , Animais , Carpas , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Fator de Crescimento Epidérmico/genética , Metaloproteinase 13 da Matriz , Modelos Biológicos , Ligação Proteica
20.
Nutr Metab Cardiovasc Dis ; 29(12): 1418-1428, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31653519

RESUMO

BACKGROUND AND AIMS: Intrauterine growth restriction (IUGR) is a state of slower fetal growth usually followed by a catch-up growth. Postnatal catch-up growth in IUGR models increases the incidence of pulmonary arterial hypertension in adulthood. Here, we hypothesize that the adverse pulmonary vascular consequences of IUGR may be improved by slowing down postnatal growth velocity. Meanwhile, cognitive function was also studied. METHODS AND RESULTS: We established an IUGR rat model by restricting maternal food throughout gestation. After birth, pups were fed a regular or restricted diet during lactation by changing litter size. Thus, there were three experimental groups according to the dam/offspring diet: C/C (gold standard), IUGR with catch-up growth (R/C) and IUGR with delayed growth (R/D). In adulthood (14 weeks of age), we assessed pulmonary vascular development by hemodynamic measurement and immunohistochemistry. Our results showed that adult R/C offspring developed an elevated mean pulmonary arterial pressure (mPAP) and pulmonary arteriolar remodeling accompanied with decreased eNOS mRNA and protein expressions compared to C/C or R/D offspring. This suggested that delayed postnatal growth improved pulmonary circulation compared to postnatal catch-up growth. Conversely, adult R/D offspring performed poorly in cognition. Behavior test and electrophysiology results exhibited a reduced synaptic plasticity. Furthermore, decreased mRNA expression levels of the memory-related gene zif268 and transcription factor recruitment factor p300 in the hippocampus region were also observed in R/D group. CONCLUSION: These findings indicate that delayed postnatal growth results in cognitive impairment, but it reverses elevations in mPAP induced by postnatal catch-up growth following IUGR.


Assuntos
Comportamento Animal , Encéfalo/crescimento & desenvolvimento , Restrição Calórica/efeitos adversos , Cognição , Disfunção Cognitiva/etiologia , Retardo do Crescimento Fetal/dietoterapia , Hipertensão Pulmonar/prevenção & controle , Artéria Pulmonar/crescimento & desenvolvimento , Fatores Etários , Fenômenos Fisiológicos da Nutrição Animal , Animais , Encéfalo/metabolismo , Disfunção Cognitiva/metabolismo , Disfunção Cognitiva/fisiopatologia , Disfunção Cognitiva/psicologia , Modelos Animais de Doenças , Proteína p300 Associada a E1A/genética , Proteína p300 Associada a E1A/metabolismo , Proteína 1 de Resposta de Crescimento Precoce/genética , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Feminino , Retardo do Crescimento Fetal/fisiopatologia , Retardo do Crescimento Fetal/psicologia , Hemodinâmica , Hipertensão Pulmonar/etiologia , Hipertensão Pulmonar/metabolismo , Hipertensão Pulmonar/fisiopatologia , Masculino , Plasticidade Neuronal , Óxido Nítrico Sintase Tipo III/genética , Óxido Nítrico Sintase Tipo III/metabolismo , Gravidez , Efeitos Tardios da Exposição Pré-Natal , Artéria Pulmonar/metabolismo , Ratos Sprague-Dawley , Remodelação Vascular , Ganho de Peso
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