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1.
Science ; 370(6513)2020 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-33033186

RESUMO

Excitotoxicity induced by NMDA receptors (NMDARs) is thought to be intimately linked to high intracellular calcium load. Unexpectedly, NMDAR-mediated toxicity can be eliminated without affecting NMDAR-induced calcium signals. Instead, excitotoxicity requires physical coupling of NMDARs to TRPM4. This interaction is mediated by intracellular domains located in the near-membrane portions of the receptors. Structure-based computational drug screening using the interaction interface of TRPM4 in complex with NMDARs identified small molecules that spare NMDAR-induced calcium signaling but disrupt the NMDAR/TRPM4 complex. These interaction interface inhibitors strongly reduce NMDA-triggered toxicity and mitochondrial dysfunction, abolish cyclic adenosine monophosphate-responsive element-binding protein (CREB) shutoff, boost gene induction, and reduce neuronal loss in mouse models of stroke and retinal degeneration. Recombinant or small-molecule NMDAR/TRPM4 interface inhibitors may mitigate currently untreatable human neurodegenerative diseases.


Assuntos
Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Descoberta de Drogas , Doenças Neurodegenerativas/metabolismo , Fármacos Neuroprotetores/química , Receptores de N-Metil-D-Aspartato/metabolismo , Proteínas Recombinantes/metabolismo , Canais de Cátion TRPM/metabolismo , Animais , Sinalização do Cálcio , AMP Cíclico/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Técnicas de Silenciamento de Genes , Humanos , Camundongos , Doenças Neurodegenerativas/tratamento farmacológico , Domínios Proteicos , Receptores de N-Metil-D-Aspartato/química , Receptores de N-Metil-D-Aspartato/uso terapêutico , Proteínas Recombinantes/química , Proteínas Recombinantes/uso terapêutico , Canais de Cátion TRPM/genética , Ativação Transcricional
2.
PLoS Genet ; 16(8): e1008963, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32780743

RESUMO

Long-term memory (LTM) formation depends on the conversed cAMP response element-binding protein (CREB)-dependent gene transcription followed by de novo protein synthesis. Thirsty fruit flies can be trained to associate an odor with water reward to form water-reward LTM (wLTM), which can last for over 24 hours without a significant decline. The role of de novo protein synthesis and CREB-regulated gene expression changes in neural circuits that contribute to wLTM remains unclear. Here, we show that acute inhibition of protein synthesis in the mushroom body (MB) αß or γ neurons during memory formation using a cold-sensitive ribosome-inactivating toxin disrupts wLTM. Furthermore, adult stage-specific expression of dCREB2b in αß or γ neurons also disrupts wLTM. The MB αß and γ neurons can be further classified into five different neuronal subsets including αß core, αß surface, αß posterior, γ main, and γ dorsal. We observed that the neurotransmission from αß surface and γ dorsal neuron subsets is required for wLTM retrieval, whereas the αß core, αß posterior, and γ main are dispensable. Adult stage-specific expression of dCREB2b in αß surface and γ dorsal neurons inhibits wLTM formation. In vivo calcium imaging revealed that αß surface and γ dorsal neurons form wLTM traces with different dynamic properties, and these memory traces are abolished by dCREB2b expression. Our results suggest that a small population of neurons within the MB circuits support long-term storage of water-reward memory in Drosophila.


Assuntos
Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Memória de Longo Prazo/fisiologia , Neurônios/metabolismo , Olfato/genética , Transativadores/genética , Animais , Animais Geneticamente Modificados , Cálcio/metabolismo , Drosophila melanogaster/fisiologia , Corpos Pedunculados/fisiologia , Neurônios/fisiologia , Biossíntese de Proteínas/genética , Recompensa , Olfato/fisiologia , Transmissão Sináptica/genética , Água
3.
PLoS Biol ; 18(8): e3000826, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32776935

RESUMO

Ca2+/calmodulin-dependent kinase II (CaMKII) regulates synaptic plasticity in multiple ways, supposedly including the secretion of neuromodulators like brain-derived neurotrophic factor (BDNF). Here, we show that neuromodulator secretion is indeed reduced in mouse α- and ßCaMKII-deficient (αßCaMKII double-knockout [DKO]) hippocampal neurons. However, this was not due to reduced secretion efficiency or neuromodulator vesicle transport but to 40% reduced neuromodulator levels at synapses and 50% reduced delivery of new neuromodulator vesicles to axons. αßCaMKII depletion drastically reduced neuromodulator expression. Blocking BDNF secretion or BDNF scavenging in wild-type neurons produced a similar reduction. Reduced neuromodulator expression in αßCaMKII DKO neurons was restored by active ßCaMKII but not inactive ßCaMKII or αCaMKII, and by CaMKII downstream effectors that promote cAMP-response element binding protein (CREB) phosphorylation. These data indicate that CaMKII regulates neuromodulation in a feedback loop coupling neuromodulator secretion to ßCaMKII- and CREB-dependent neuromodulator expression and axonal targeting, but CaMKIIs are dispensable for the secretion process itself.


Assuntos
Astrócitos/metabolismo , Fator Neurotrófico Derivado do Encéfalo/genética , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/genética , Cálcio/metabolismo , Neurônios/metabolismo , Subunidades Proteicas/genética , Animais , Astrócitos/citologia , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/deficiência , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Retroalimentação Fisiológica , Regulação da Expressão Gênica , Hipocampo/citologia , Hipocampo/metabolismo , Camundongos , Camundongos Transgênicos , Neurônios/citologia , Fosforilação , Cultura Primária de Células , Subunidades Proteicas/deficiência , Sinapses/fisiologia , Transmissão Sináptica , Imagem com Lapso de Tempo
4.
J Stroke Cerebrovasc Dis ; 29(8): 104850, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32689640

RESUMO

BACKGROUND: Following the recent discovery that microRNA-134-5p (miR-134-5p) is elevated in the early stages of acute myocardial infarction (AMI), we examined the specific role of miR-134-5p in cardiomyocytes during AMI. METHODS: To study miR-134-5p's role in the context of AMI, we used a combination of in vitro experiments in H2O2-treated or hypoxic cardiomyocyte cell cultures as well as in vivo experiments in a murine model of AMI. RESULTS: H2O2- and hypoxia-induced cardiomyocyte injury upregulated miR-134-5p expression. miR-134-5p overexpression increased cardiomyocyte apoptosis, whereas miR-134-5p inhibition reduced cardiomyocyte apoptosis. We discovered that the transcription factor cAMP-responsive element binding protein 1 (Creb1) is a functional target of miR-134-5p responsible for regulating cardiomyocyte apoptosis. In vivo AMI resulted in the upregulation and downregulation of miR-134-5p and Creb1 in the infarct area, respectively. Circulating miR-134-5p levels were also increased at days 1 and 2 post-AMI. Modulation of myocardial miR-124-5p expression by intramyocardial injection of antagomiR-134-5p or agomiR-134-5p significantly affected cardiomyocyte apoptosis, infarct size, and cardiac function in vivo. CONCLUSIONS: miR-134-5p/Creb1 axis dysregulation plays a role in hypoxia- or oxidative stress-induced cardiomyocyte apoptosis as well as AMI. Circulating miR-134-5p may show promise as a biomarker for AMI or post-AMI cardiac dysfunction. Manipulating the miR-134-5p/Creb1 axis through either inhibition of miR-134-5p or overexpression of Creb1 may show promise as a novel therapeutic strategy to attenuate cardiac dysfunction following AMI.


Assuntos
Antagomirs/administração & dosagem , Apoptose , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , MicroRNAs/antagonistas & inibidores , Infarto do Miocárdio/prevenção & controle , Miócitos Cardíacos/metabolismo , Regiões 3' não Traduzidas , Animais , Sítios de Ligação , Hipóxia Celular , Células Cultivadas , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Modelos Animais de Doenças , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Peróxido de Hidrogênio/toxicidade , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Infarto do Miocárdio/genética , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , Miócitos Cardíacos/patologia , Estresse Oxidativo , Transdução de Sinais , Regulação para Cima
5.
Arterioscler Thromb Vasc Biol ; 40(8): 1935-1941, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32580631

RESUMO

OBJECTIVE: Genetic determinants of severe hypertriglyceridemia include both common variants with small effects (assessed using polygenic risk scores) plus heterozygous and homozygous rare variants in canonical genes directly affecting triglyceride metabolism. Here, we broadened our scope to detect associations with rare loss-of-function variants in genes affecting noncanonical pathways, including those known to affect triglyceride metabolism indirectly. Approach and Results: From targeted next-generation sequencing of 69 metabolism-related genes in 265 patients of European descent with severe hypertriglyceridemia (≥10 mmol/L or ≥885 mg/dL) and 477 normolipidemic controls, we focused on the association of rare heterozygous loss-of-function variants in individual genes. We observed that compared with controls, severe hypertriglyceridemia patients were 20.2× (95% CI, 1.11-366.1; P=0.03) more likely than controls to carry a rare loss-of-function variant in CREB3L3, which encodes a transcription factor that regulates several target genes with roles in triglyceride metabolism. CONCLUSIONS: Our findings indicate that rare variants in a noncanonical gene for triglyceride metabolism, namely CREB3L3, contribute significantly to severe hypertriglyceridemia. Secondary genes and pathways should be considered when evaluating the genetic architecture of this complex trait.


Assuntos
Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Hipertrigliceridemia/genética , Adulto , Idoso , Apolipoproteína A-V/genética , Feminino , Heterozigoto , Humanos , Lipase Lipoproteica/genética , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Triglicerídeos/metabolismo
7.
Proc Natl Acad Sci U S A ; 117(21): 11760-11769, 2020 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-32393629

RESUMO

Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) are two related neurodegenerative diseases that present with similar TDP-43 pathology in patient tissue. TDP-43 is an RNA-binding protein which forms aggregates in neurons of ALS and FTD patients as well as in a subset of patients diagnosed with other neurodegenerative diseases. Despite our understanding that TDP-43 is essential for many aspects of RNA metabolism, it remains obscure how TDP-43 dysfunction contributes to neurodegeneration. Interestingly, altered neuronal dendritic morphology is a common theme among several neurological disorders and is thought to precede neurodegeneration. We previously found that both TDP-43 overexpression (OE) and knockdown (KD) result in reduced dendritic branching of cortical neurons. In this study, we used TRIBE (targets of RNA-binding proteins identified by editing) as an approach to identify signaling pathways that regulate dendritic branching downstream of TDP-43. We found that TDP-43 RNA targets are enriched for pathways that signal to the CREB transcription factor. We further found that TDP-43 dysfunction inhibits CREB activation and CREB transcriptional output, and restoring CREB signaling rescues defects in dendritic branching. Finally, we demonstrate, using RNA sequencing, that TDP-43 OE and KD cause similar changes in the abundance of specific messenger RNAs, consistent with their ability to produce similar morphological defects. Our data therefore provide a mechanism by which TDP-43 dysfunction interferes with dendritic branching, and may define pathways for therapeutic intervention in neurodegenerative diseases.


Assuntos
Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico , Proteínas de Ligação a DNA , Dendritos , Regulação da Expressão Gênica/genética , Transdução de Sinais , Animais , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Dendritos/metabolismo , Dendritos/patologia , Células HEK293 , Humanos , RNA Mensageiro/metabolismo , Ratos , Transdução de Sinais/genética , Transdução de Sinais/fisiologia , Proteinopatias TDP-43
8.
Epilepsia ; 61(6): 1240-1252, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32463128

RESUMO

OBJECTIVE: Activity-dependent changes have been reported in animal models and in human epileptic specimens and could potentially be used as tissue biomarkers to evaluate the propensity of a tissue to generate seizure activity. In this context, cAMP-response element binding protein (CREB) activation was specifically reported in human epileptic foci and related mainly to interictal spike activity. To get further insights into CREB activation in human epilepsy, we analyzed pCREB expression on brain tissue samples from patients who underwent surgery for drug-resistant focal epilepsy, correlating this expression with intracranial stereo-electroencephalography (SEEG) recording in a subgroup. METHODS: Neocortical specimens from patients with neuropathological diagnosis of no lesion (cryptogenic), malformations of cortical development,mainly type II focal cortical dysplasia (FCD), and hippocampi with and without hippocampal sclerosis have been analyzed by immunohistochemistry. Peritumoral cortex from non-epileptic patients and autoptic samples were used as controls, whereas rat brains were used to test possible loss of pCREB antigenicity due to fixation procedures and postmortem delay. RESULTS: pCREB was consistently expressed in layer II neuronal nuclei in regions with normal cortical lamination both in epileptic and non-epileptic surgical tissues. In patients with SEEG recordings, this anatomical pattern was unrelated to the presence of interictal spike activity. Conversely, in the core of type II FCD, as well as in other developmental malformations, pCREB was scattered without any laminar specificity. Furthermore, quantitative data did not reveal significant differences between epileptic and non-epileptic tissues, except for an increased immunoreactivity in the core of type IIB FCD lesion related mainly to reactive glial and balloon cells. SIGNIFICANCE: The present data argue against the reliability of pCREB immunohistochemistry as a marker of epileptic focus but underscores its layer-related expression, suggesting a potential application in the study of malformations of cortical development, a wide range of diseases arising from perturbations of normal brain development.


Assuntos
Encéfalo/metabolismo , Encéfalo/cirurgia , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/biossíntese , Epilepsia Resistente a Medicamentos/metabolismo , Epilepsia Resistente a Medicamentos/cirurgia , Adolescente , Adulto , Idoso , Animais , Encéfalo/patologia , Pré-Escolar , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Epilepsia Resistente a Medicamentos/genética , Feminino , Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Ratos , Ratos Sprague-Dawley , Técnicas Estereotáxicas
9.
Life Sci ; 254: 117795, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32417373

RESUMO

AIMS: The primary focus of this study was to explore the effects of cyclic AMP response element-binding protein H (CREBH) on the development of nonalcoholic fatty liver disease (NAFLD). MATERIALS AND METHODS: CREBH knockout (KO) and wildtype (WT) mice were averagely divided into a methionine and choline-deficient (MCD) or high fat (HF) diet group and respective chow diet (CD) groups. Mice were sacrificed after 4-week treatment for MCD model and 24-week treatment for HF model. KEY FINDINGS: Characteristics of nonalcoholic steatohepatitis-related liver fibrosis in KO-MCD/HF group were verified by hepatic histological analyses. Compared with WT-MCD/HF group, levels of plasma ALT and hepatic hydroxyproline increased in KO-MCD/HF group. Significantly higher levels of MCP-1, αSMA, Desmin, COL-1, TIMP-1, TGF-ß1, TGF-ß2 were found while MMP-9 and FGF21 mRNA levels decreased in KO-MCD/HF group. There was also a distinct difference of mRNA levels of TNFα, CTGF and CCND1 in KO-HF group compared with controls. Protein levels of MCP-1, BAX, αSMA, COL-1, TGF-ß1 and SMAD2/3 significantly increased in KO-MCD/HF group and CCND1 was also upregulated in KO-HF group compared to their counterparts. SIGNIFICANCE: CREBH knockout may primarily regulate the TGF-ß1 signaling pathway via TGF-ß2 and FGF21 resulting in more severe inflammation and fibrosis in NAFLD.


Assuntos
Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Cirrose Hepática/genética , Hepatopatia Gordurosa não Alcoólica/genética , Fator de Crescimento Transformador beta/metabolismo , Alanina Transaminase/sangue , Animais , Deficiência de Colina , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/deficiência , Dieta Hiperlipídica , Fatores de Crescimento de Fibroblastos/biossíntese , Hidroxiprolina/metabolismo , Lipídeos/sangue , Cirrose Hepática/sangue , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Masculino , Metionina/deficiência , Camundongos , Camundongos Knockout , Hepatopatia Gordurosa não Alcoólica/sangue , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Transdução de Sinais/genética
10.
Am J Physiol Endocrinol Metab ; 319(1): E232-E244, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32369417

RESUMO

Voltage-gated Ca2+ (CaV) channels are expressed in endocrine cells where they contribute to hormone secretion. Diverse chemical messengers, including epidermal growth factor (EGF), are known to affect the expression of CaV channels. Previous studies have shown that EGF increases Ca2+ currents in GH3 pituitary cells by increasing the number of high voltage-activated (HVA) CaV channels at the cell membrane, which results in enhanced prolactin (PRL) secretion. However, little is known regarding the mechanisms underlying this regulation. Here, we show that EGF actually increases the expression of the CaVα2δ-1 subunit, a key molecular component of HVA channels. The analysis of the gene promoter encoding CaVα2δ-1 (CACNA2D1) revealed binding sites for transcription factors activated by the Ras/Raf/MEK/ERK signaling cascade. Chromatin immunoprecipitation and site-directed mutagenesis showed that ELK-1 is crucial for the transcriptional regulation of CACNA2D1 in response to EGF. Furthermore, we found that EGF increases the membrane expression of CaVα2δ-1 and that ELK-1 overexpression increases HVA current density, whereas ELK-1 knockdown decreases the functional expression of the channels. Hormone release assays revealed that CaVα2δ-1 overexpression increases PRL secretion. These results suggest a mechanism for how EGF, by activating the Ras/Raf/MEK/ERK/ELK-1 pathway, may influence the expression of HVA channels and the secretory behavior of pituitary cells.


Assuntos
Canais de Cálcio Tipo L/genética , Fator de Crescimento Epidérmico/metabolismo , Regulação da Expressão Gênica , Sistema de Sinalização das MAP Quinases/genética , Proteínas Elk-1 do Domínio ets/genética , Quinases raf/genética , Proteínas ras/genética , Animais , Canais de Cálcio Tipo L/metabolismo , Linhagem Celular Tumoral , Imunoprecipitação da Cromatina , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Técnicas de Silenciamento de Genes , Mutagênese Sítio-Dirigida , Regiões Promotoras Genéticas , Ratos , Transdução de Sinais , Proteínas Elk-1 do Domínio ets/metabolismo , Quinases raf/metabolismo , Proteínas ras/metabolismo
11.
Cell Mol Life Sci ; 77(20): 4049-4067, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32347317

RESUMO

Altered expression and function of the transcription factor cyclic AMP response-binding protein (CREB) has been identified to play an important role in cancer and is associated with the overall survival and therapy response of tumor patients. This review focuses on the expression and activation of CREB under physiologic conditions and in tumors of distinct origin as well as the underlying mechanisms of CREB regulation by diverse stimuli and inhibitors. In addition, the clinical relevance of CREB is summarized, including its use as a prognostic and/or predictive marker as well as a therapeutic target.


Assuntos
Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Animais , Biomarcadores Tumorais/genética , AMP Cíclico/genética , Regulação da Expressão Gênica/genética , Humanos , Neoplasias/genética , Transdução de Sinais/genética
12.
Proc Natl Acad Sci U S A ; 117(19): 10246-10253, 2020 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-32327610

RESUMO

The evolution of insect resistance to pesticides poses a continuing threat to agriculture and human health. While much is known about the proximate molecular and biochemical mechanisms that confer resistance, far less is known about the regulation of the specific genes/gene families involved, particularly by trans-acting factors such as signal-regulated transcription factors. Here we resolve in fine detail the trans-regulation of CYP6CM1, a cytochrome P450 that confers resistance to neonicotinoid insecticides in the whitefly Bemisia tabaci, by the mitogen-activated protein kinase (MAPK)-directed activation of the transcription factor cAMP-response element binding protein (CREB). Reporter gene assays were used to identify the putative promoter of CYP6CM1, but no consistent polymorphisms were observed in the promoter of a resistant strain of B. tabaci (imidacloprid-resistant, IMR), which overexpresses this gene, compared to a susceptible strain (imidacloprid-susceptible, IMS). Investigation of potential trans-acting factors using in vitro and in vivo assays demonstrated that the bZIP transcription factor CREB directly regulates CYP6CM1 expression by binding to a cAMP-response element (CRE)-like site in the promoter of this gene. CREB is overexpressed in the IMR strain, and inhibitor, luciferase, and RNA interference assays revealed that a signaling pathway of MAPKs mediates the activation of CREB, and thus the increased expression of CYP6CM1, by phosphorylation-mediated signal transduction. Collectively, these results provide mechanistic insights into the regulation of xenobiotic responses in insects and implicate both the MAPK-signaling pathway and a transcription factor in the development of pesticide resistance.


Assuntos
Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Resistência a Medicamentos/genética , Regulação da Expressão Gênica , Hemípteros/crescimento & desenvolvimento , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Neonicotinoides/farmacologia , Nitrocompostos/farmacologia , Animais , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Sistema Enzimático do Citocromo P-450/genética , Hemípteros/efeitos dos fármacos , Hemípteros/genética , Hemípteros/metabolismo , Inseticidas/farmacologia , Proteínas Quinases Ativadas por Mitógeno/genética , Mutação , Fosforilação , Regiões Promotoras Genéticas
13.
Neurobiol Aging ; 91: 66-75, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32224066

RESUMO

Cognitive impairments and circadian rhythm disorders are the main clinical manifestations of Alzheimer's disease (AD). Orexin has been reported as abnormally elevated in the cerebrospinal fluid of AD patients, accompanied with cognitive impairments. Our recent research revealed that suvorexant, a dual orexin receptor antagonist, could improve behavioral circadian rhythm disorders in 9-month-old APP/PS1 mice. Here we further observed whether suvorexant could ameliorate the cognitive decline in APP/PS1 mice by using behavioral tests, and investigated the possible mechanisms by in vivo electrophysiological recording, western blot, and immunochemistry. The results showed that suvorexant treatment effectively ameliorated the cognitive impairments, alleviated in vivo hippocampal long-term potentiation suppression, restored the circadian phosphorylated CREB expression in the hippocampus, and reduced amyloid-ß protein deposition in the hippocampus and cortex in APP/PS1 mice. These results indicate that the neuroprotective effects of suvorexant against AD are involved in the reduction of amyloid-ß plaques, improvement of synaptic plasticity, and circadian expression of phosphorylated CREB, suggesting that suvorexant could be beneficial to the prevention and treatment of AD.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Azepinas/farmacologia , Azepinas/uso terapêutico , Transtornos Cronobiológicos/tratamento farmacológico , Disfunção Cognitiva/tratamento farmacológico , Neuroprostanos , Antagonistas dos Receptores de Orexina , Triazóis/farmacologia , Triazóis/uso terapêutico , Doença de Alzheimer/líquido cefalorraquidiano , Doença de Alzheimer/complicações , Peptídeos beta-Amiloides/genética , Peptídeos beta-Amiloides/metabolismo , Animais , Transtornos Cronobiológicos/etiologia , Disfunção Cognitiva/líquido cefalorraquidiano , Disfunção Cognitiva/etiologia , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Modelos Animais de Doenças , Expressão Gênica/efeitos dos fármacos , Hipocampo/metabolismo , Hipocampo/fisiopatologia , Potenciação de Longa Duração/efeitos dos fármacos , Camundongos Transgênicos , Plasticidade Neuronal/efeitos dos fármacos , Orexinas/líquido cefalorraquidiano
14.
Brain Tumor Pathol ; 37(2): 76-80, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32215804

RESUMO

Intracranial myxoid mesenchymal tumors harboring EWSR1 fusions with CREB transcriptional factor gene families were recently described in several case reports and a few case series and this tumor closely resembles the myxoid variant of angiomatoid fibrous histiocytoma. We herein present an intracranial mesenchymal myxoid tumor arising in the third ventricle of a middle-aged woman. The tumor displayed prominent myxoid features consisting of mildly atypical oval to round cells, arranged in reticular and cord-like structures, with starburst-like amianthoid fibers, whereas it lacked pseudoangiomatoid spaces, pseudocapsules and lymphoid cuffing. Immunophenotypically, tumor cells were positive for EMA, desmin, and ALK (focal). EWSR1 and CREB1 rearrangements were identified using FISH assay. The proliferation index was low. It is currently uncertain whether these myxoid tumors represent a variant of angiomatoid fibrous histiocytoma or a novel tumor entity.


Assuntos
Neoplasias Encefálicas/genética , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Fusão Gênica , Histiocitoma Fibroso Maligno/genética , Proteína EWS de Ligação a RNA/genética , Neoplasias Encefálicas/patologia , Feminino , Rearranjo Gênico , Histiocitoma Fibroso Maligno/patologia , Humanos , Pessoa de Meia-Idade
15.
Mol Biol Rep ; 47(3): 2023-2034, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32030599

RESUMO

The purpose of the current study was to examine the neuroprotective effect of rutin against colistin-induced neurotoxicity in rats. Thirty-five male Sprague Dawley rats were randomly divided into 5 groups. The control group (orally received physiological saline), the rutin group (orally administered 100 mg/kg body weight), the colistin group (i.p. administered 15 mg/kg body weight), the Col + Rut 50 group (i.p. administered 15 mg/kg body weight of colistin, and orally received 50 mg/kg body weight of rutin), the Col + Rut 100 group (i.p. administered 15 mg/kg body weight of colistin, and orally received 100 mg/kg body weight of rutin). Administration of colistin increased levels of glial fibrillary acidic protein and brain-derived neurotrophic factor and acetylcholinesterase and butyrylcholinesterase activities while decreasing level of cyclic AMP response element binding protein and extracellular signal regulated kinases 1 and 2 (ERK1/2) expressions. Colistin increased oxidative impairments as evidenced by a decrease in level of nuclear factor erythroid 2-related factor 2 (Nrf-2), glutathione, superoxide dismutase, glutathione peroxidase and catalase activities, and increased malondialdehyde content. Colistin also increased the levels of the apoptotic and inflammatoric parameters such as cysteine aspartate specific protease-3 (caspase-3), p53, B-cell lymphoma-2 (Bcl-2), nuclear factor kappa B (NF-κB), Bcl-2 associated X protein (Bax), tumor necrosis factor-α (TNF-α) and neuronal nitric oxide synthase (nNOS). Rutin treatment restored the brain function by attenuating colistin-induced oxidative stress, apoptosis, inflammation, histopathological and immunohistochemical alteration suggesting that rutin supplementation mitigated colistin-induced neurotoxicity in male rats.


Assuntos
Apoptose/efeitos dos fármacos , Fator Neurotrófico Derivado do Encéfalo/genética , Colistina/farmacologia , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Inflamação/etiologia , Inflamação/metabolismo , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Rutina/farmacologia , Animais , Biomarcadores , Encéfalo/metabolismo , Encéfalo/patologia , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Colistina/efeitos adversos , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Imuno-Histoquímica , Inflamação/patologia , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Ratos
16.
BMC Genomics ; 21(1): 103, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32000663

RESUMO

BACKGROUND: Luman is a member of CREB3 (cAMP responsive element-binding) subfamily of the basic leucine-zipper (bZIP) transcription factors. It may play an important regulatory role during the decidualization process since Luman was highly expressed in the decidual cells. However, the exact molecular mechanisms of how Luman regulating decidualization is unknown. RESULTS: Using an in vitro model, we prove that Luman knockdown significantly affects the decidualization process of mice endometrial stromal cells (ESCs) as the expression of two decidual markers PRL8a2 and PRL3c1 were repressed. We employed massively parallel RNA sequencing (RNA-Seq) to understand the changes in the transcriptional landscape associated with knockdown of Luman in ESCs during in vitro decidualization. We found significant dysregulation of genes related to protein processing in the endoplasmic reticulum (ER). Several genes involved in decidualization including bone morphogenetic proteins (e.g. BMP1, BMP4, BMP8A, BMP2, and BMP8B), growth factor-related genes (e.g. VEGFB, FGF10, and FGFR2), and transcription factors (IF4E, IF4A2, WNT4, WNT9A, ETS1, NOTCH1, IRX1, IDB1, IDB2, and IDB3), show altered expression. We also found that the knockdown of Luman is associated with increased expression of cell cycle-related genes including cycA1, cycB1, cycB2, CDK1, CDK2, and PLPK1, which resulted in an increased proportion of ESCs in the G1 phase. Differentially expressed genes (DEGs) were highly enriched on ECM-receptor interaction signaling, endoplasmic reticulum protein processing, focal adhesion, and PI3K-Akt signaling pathways. CONCLUSIONS: Luman knockdown results in widespread gene dysregulation during decidualization of ESCs. Genes involved in protein processing in ER, bone morphogenetic protein, growth factor, and cell cycle progression were identified as particularly important for explaining the decidual deficiency observed in this in vitro model. Therefore, this study provides clues as to the underlying mechanisms that may expand our understanding of gene regulation during decidualization.


Assuntos
Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Decídua/metabolismo , Perfilação da Expressão Gênica/veterinária , Redes Reguladoras de Genes , Animais , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Endométrio/metabolismo , Feminino , Regulação da Expressão Gênica , Técnicas de Silenciamento de Genes , Sequenciamento de Nucleotídeos em Larga Escala/veterinária , Camundongos , Análise de Sequência de RNA/veterinária
17.
J Steroid Biochem Mol Biol ; 199: 105608, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31996328

RESUMO

Ovarian granulosa cells, known to be endocrine cells, have well active TLR4-/NFKB signalling mediated innate immune capabilities. We have previously shown that endotoxin not only transiently regulates proinflammatory cytokines but cells become tolerant on repeated exposure to endotoxin and impaired granulosa cells functions, which includes downregulation of CYP19A1 gene. To understand further endotoxin tolerance and impaired granulosa cells function, genome-wide transcriptomic profiling in endotoxin tolerant buffalo granulosa cells (bGCs) identified miR-326 as upregulated amongst top 5 DE miRNAs [unpublished data] and qPCR validation confirmed its upregulation during endotoxin tolerance. In silico analyses showed that miR-326 targets CYP19A1 gene. Therefore, in the present study, we elucidated the role of miR-326 in buffalo granulosa cells (bGCs). We first validated its expression vis-à-vis CYP19A1 gene expression in bGCs, both in vivo and in vitro. Results showed an inverse relationship between miR-326 and CYP19A1 expression. Similarly, transcription factors, known to be involved in CYP19A1 gene regulation, CREB and C/EBP-ß expression was also found to be decreased in granulosa cells mimicking pre-ovulatory follicular stage. Further, miR-326 mimic was transfected to bGCs in culture and expression of CYP19A1 and CREB & C/EBP-ß and genes encoding other enzymes of steroidogenesis pathway were also analyzed. The present study results showed that miR-326 significantly inhibits the expression of CYP19A1 gene while expression of transcription factors CREB and C/EBP-ß was found to be upregulated. The expression of STAR and CYP11A1 was found to be unaffected. To elucidate the molecular mechanism of miR-326 mediated downregulation of CYP19A1, binding analyses of RNA polymerase II and CEBP-ß to CYP19A1 gene promoter II was analyzed. The result also showed decreased binding of RNA polymerase II with increased binding of CEBP-ß to CYP19A1 gene promoter II in bGCs, transfected with miR-326 as compared to control. In summary, our results suggest that miR-326 upregulate CREB and CREB may activate C/EBP-ß and later inhibited the transcription of CYP19A1 and decreased estradiol-17b production. The miR-326 mediated down-regulation of the CYP19A1 gene involving CREB-C/EBP-ß can be exploited in developing strategies to attenuate endotoxin-mediated tolerance induced impaired granulosa cells function to ensure proper fertility in females.


Assuntos
Aromatase/genética , Estradiol/genética , Estrogênios/genética , MicroRNAs/genética , Animais , Búfalos/genética , Búfalos/metabolismo , Proteína beta Intensificadora de Ligação a CCAAT/genética , Bovinos , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Estradiol/biossíntese , Estrogênios/biossíntese , Feminino , Regulação da Expressão Gênica/genética , Células da Granulosa/metabolismo , Regiões Promotoras Genéticas , Transdução de Sinais
18.
Psychogeriatrics ; 20(1): 35-43, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30950168

RESUMO

AIM: Obesity contributes to the development of mild cognitive impairment, but the potential role of normal weight obesity in this disease has not been explored in humans. The aim of the study was to reveal the relationship between normal weight obesity and mild cognitive impairment in elderly individuals. METHODS: This study consisted of 360 patients with amnestic mild cognitive impairment and 360 cognitively normal controls. Normal weight obesity was defined as having metabolic syndrome but a normal weight. Metabolic health meant having no metabolic syndrome. Reverse transcription quantitative real-time polymerase chain reaction was adopted to measure the messenger RNA expression of four cognitive-related genes (amyloid precursor protein, cyclic adenosine monophosphate-responsive element-binding protein 1, sortilin-related receptor 1, and synapsin I) in peripheral blood mononuclear cells. RESULTS: Normal weight obesity was related to a higher risk of amnestic mild cognitive impairment (odds ratio = 3.14, 95% confidence interval: 2.13-4.60). In the patients, the expression of each gene in the peripheral blood mononuclear cells was linearly related to Mini-Mental State Examination and Montreal Cognitive Assessment scores (P < 0.05). The expression of these genes in the patients with metabolic health deviated from the normal levels found in the controls (P < 0.05), and the deviations were more significant in the patients with normal weight obesity (P < 0.05). CONCLUSION: Normal weight obesity may be a potential risk factor for amnestic mild cognitive impairment in elderly. This relationship was reflected in the abnormal expression of several cognitive-related genes in peripheral blood mononuclear cells.


Assuntos
Disfunção Cognitiva/genética , Expressão Gênica , Leucócitos Mononucleares , Síndrome Metabólica/genética , Obesidade/genética , RNA Mensageiro , Idoso , Idoso de 80 Anos ou mais , Amnésia/complicações , Precursor de Proteína beta-Amiloide/sangue , Precursor de Proteína beta-Amiloide/genética , Biomarcadores/sangue , Índice de Massa Corporal , Estudos de Casos e Controles , China/epidemiologia , Disfunção Cognitiva/complicações , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/sangue , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Feminino , Humanos , Peso Corporal Ideal , Proteínas Relacionadas a Receptor de LDL/sangue , Proteínas Relacionadas a Receptor de LDL/genética , Masculino , Proteínas de Membrana Transportadoras/sangue , Proteínas de Membrana Transportadoras/genética , Testes de Estado Mental e Demência , Síndrome Metabólica/classificação , Obesidade/classificação , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sinapsinas/sangue , Sinapsinas/genética
19.
BMB Rep ; 53(2): 82-87, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31072448

RESUMO

Circular RNAs (circRNAs), one kind of non-coding RNA, have been reported as critical regulators for modulating gene expression in cancer. In this study, microarray analysis was used to screen circRNA expression profiles of bladder cancer (BC) 5637 cells, T24 cells and normal control SV-HUC-1 cells. The data from the microarray showed that hsa_circ_0075828 (named circCASC15) was most highly expressed in 5637 and T24 cells. circCASC15 was highly expressed in BC tissues and cells. Overexpression of circCASC15 was closely associated with BC tumor stage and promoted cell proliferation significantly in vitro and in vivo. Mechanistically, circCASC15 could act as miR-1224-5p sponge to activate the expression of CREB1 to promote cell proliferation in BC. In short, circCASC15 promotes cell proliferation in BC, which might be a new molecular target for BC diagnosis and therapy. [BMB Reports 2020; 53(2): 82-87].


Assuntos
Carcinoma/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , MicroRNAs/metabolismo , RNA Circular/fisiologia , Neoplasias da Bexiga Urinária/genética , Animais , Carcinoma/patologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Citoplasma/genética , Citoplasma/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Camundongos Nus , MicroRNAs/genética , Análise em Microsséries , Estadiamento de Neoplasias , Prognóstico , Neoplasias da Bexiga Urinária/metabolismo , Neoplasias da Bexiga Urinária/patologia
20.
J Endocrinol ; 244(2): 353-367, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31770098

RESUMO

High-fat diet (HFD) not only induces insulin resistance in liver, but also causes autophagic imbalance and metabolic disorders, increases chronic inflammatory response and induces mitochondrial dysfunction. Calcium/calmodulin-dependent protein kinase IV (CaMKIV) has recently emerged as an important regulator of glucose metabolism and skeletal muscle insulin action. Its activation has been involved in the improvement of hepatic and adipose insulin action. But the underlying mechanism is not fully understood. In the present study, we aimed to address the direct effects of CaMKIV in vivo and to evaluate the potential interaction of impaired insulin sensitivity and autophagic disorders in hepatic insulin resistance. Our results indicated obese mice receiving CaMKIV showed decreased blood glucose and serum insulin and improved insulin sensitivity as well as increased glucose tolerance compared with vehicle injection. Meanwhile, defective hepatic autophagy activity, impaired insulin signaling, increased inflammatory response and mitochondrial dysfunction in liver tissues which are induced by high-fat diet were also effectively alleviated by injection of CaMKIV. Consistent with these results, the addition of CaMKIV to the culture medium of BNL cl.2 hepatocytes markedly restored palmitate-induced hepatic insulin resistance and autophagic imbalance. These effects were nullified by blockade of cyclic AMP response element-binding protein (CREB), indicating the causative role of CREB in action of CaMKIV. Our findings suggested that CaMKIV restores hepatic autophagic imbalance and improves impaired insulin sensitivity via phosphorylated CREB signaling pathway, which may offer novel opportunities for treatment of obesity and diabetes.


Assuntos
Autofagia , Proteína Quinase Tipo 4 Dependente de Cálcio-Calmodulina/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Fígado/metabolismo , Obesidade/metabolismo , Animais , Proteína Quinase Tipo 4 Dependente de Cálcio-Calmodulina/genética , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Dieta Hiperlipídica/efeitos adversos , Glucose/metabolismo , Hepatócitos/citologia , Hepatócitos/metabolismo , Humanos , Insulina/metabolismo , Resistência à Insulina , Fígado/citologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Obesos , Obesidade/etiologia , Obesidade/genética , Obesidade/fisiopatologia , Fosforilação
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