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1.
Nat Commun ; 11(1): 137, 2020 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-31919425

RESUMO

Public archives of next-generation sequencing data are growing exponentially, but the difficulty of marshaling this data has led to its underutilization by scientists. Here, we present ASCOT, a resource that uses annotation-free methods to rapidly analyze and visualize splice variants across tens of thousands of bulk and single-cell data sets in the public archive. To demonstrate the utility of ASCOT, we identify novel cell type-specific alternative exons across the nervous system and leverage ENCODE and GTEx data sets to study the unique splicing of photoreceptors. We find that PTBP1 knockdown and MSI1 and PCBP2 overexpression are sufficient to activate many photoreceptor-specific exons in HepG2 liver cancer cells. This work demonstrates how large-scale analysis of public RNA-Seq data sets can yield key insights into cell type-specific control of RNA splicing and underscores the importance of considering both annotated and unannotated splicing events.


Assuntos
Processamento Alternativo/genética , Biologia Computacional/métodos , Análise de Dados , Células Fotorreceptoras/citologia , Sítios de Splice de RNA/genética , Animais , Linhagem Celular Tumoral , Expressão Gênica/genética , Células Hep G2 , Ribonucleoproteínas Nucleares Heterogêneas/genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Neoplasias Hepáticas/genética , Camundongos , Proteínas do Tecido Nervoso/biossíntese , Proteínas do Tecido Nervoso/genética , Neurônios/citologia , Proteína de Ligação a Regiões Ricas em Polipirimidinas/genética , Proteínas de Ligação a RNA/biossíntese , Proteínas de Ligação a RNA/genética , Retina/citologia , Análise de Sequência de RNA/métodos
2.
Elife ; 82019 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-31392959

RESUMO

Proper connectivity of the nervous system requires temporal and spatial control of axon guidance signaling. As commissural axons navigate across the CNS midline, ROBO-mediated repulsion has traditionally been thought to be repressed before crossing, and then to become upregulated after crossing. The regulation of the ROBO receptors involves multiple mechanisms that control protein expression, trafficking, and activity. Here, we report that mammalian ROBO1 and ROBO2 are not uniformly inhibited precrossing and are instead subject to additional temporal control via alternative splicing at a conserved microexon. The NOVA splicing factors regulate the developmental expression of ROBO1 and ROBO2 variants with small sequence differences and distinct guidance activities. As a result, ROBO-mediated axonal repulsion is activated early in development to prevent premature crossing and becomes inhibited later to allow crossing. Postcrossing, the ROBO1 and ROBO2 isoforms are disinhibited to prevent midline reentry and to guide postcrossing commissural axons to distinct mediolateral positions.


Assuntos
Processamento Alternativo , Regulação da Expressão Gênica no Desenvolvimento , Proteínas do Tecido Nervoso/biossíntese , Crescimento Neuronal , Receptores Imunológicos/biossíntese , Animais , Camundongos , Camundongos Knockout , Proteínas do Tecido Nervoso/genética , Receptores Imunológicos/genética
3.
Biomed Res Int ; 2019: 7420189, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31396533

RESUMO

Toll-like receptors mediate important cellular immune responses upon activation via various pathogenic stimuli such as bacterial or viral components. The activation and subsequent secretion of cytokines and proinflammatory factors occurs in the whole body including the brain. The subsequent inflammatory response is crucial for the immune system to clear the pathogen(s) from the body via the innate and adaptive immune response. Within the brain, astrocytes, neurons, microglia, and oligodendrocytes all bear unique compositions of Toll-like receptors. Besides pathogens, cellular damage and abnormally folded protein aggregates, such as tau and Amyloid beta peptides, have been shown to activate Toll-like receptors in neurodegenerative diseases such as Alzheimer's disease. This review provides an overview of the different cell type-specific Toll-like receptors of the human brain, their activation mode, and subsequent cellular response, as well as their activation in Alzheimer's disease. Finally, we critically evaluate the therapeutic potential of targeting Toll-like receptors for treatment of Alzheimer's disease as well as discussing the limitation of mouse models in understanding Toll-like receptor function in general and in Alzheimer's disease.


Assuntos
Doença de Alzheimer/metabolismo , Encéfalo/metabolismo , Regulação da Expressão Gênica , Proteínas do Tecido Nervoso/biossíntese , Receptores Toll-Like/biossíntese , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/biossíntese , Encéfalo/patologia , Humanos , Especificidade de Órgãos
4.
Med Hypotheses ; 131: 109309, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31443781

RESUMO

Stroke and traumatic brain injury (TBI) are significant clinical problems characterized by high rate of mortality and long-lasting disabilities, and an unmet need for new treatments. Current experimental stroke and TBI research are evolving to focus more on understanding the brain's self-protective mechanisms to meet the critical need of developing new therapies for these disorders. In this hypothesis-based manuscript, I provide several lines of evidence that peptidase neurolysin (Nln) is one of the brain's potent, self-protective mechanisms promoting preservation and recovery of the brain after acute injury. Based on published experimental observations and ongoing studies in our laboratory, I posit that Nln is a compensatory and cerebroprotective mechanism in the post-stroke/TBI brain that functions to process a diverse group of extracellular neuropeptides and by that to reduce excitotoxicity, oxidative stress, edema formation, blood brain barrier hyper-permeability, and neuroinflammation. If this hypothesis is correct, Nln could potentially serve as a single therapeutic target to modulate the function of multiple targets, the involved neuropeptide systems, critically involved in various mechanisms of brain injury and cerebroprotection/restoration. Such multi-pathway target would be highly desired for pharmacotherapy of stroke and TBI, because targeting one pathophysiological pathway has proven to be ineffective for such complex disorders.


Assuntos
Lesões Encefálicas Traumáticas/metabolismo , Metaloendopeptidases/fisiologia , Proteínas do Tecido Nervoso/fisiologia , Neuropeptídeos/metabolismo , Acidente Vascular Cerebral/metabolismo , Doença Aguda , Animais , Lesões Encefálicas Traumáticas/fisiopatologia , Morte Celular , Hipóxia Celular , Células Cultivadas , Córtex Cerebral/embriologia , Córtex Cerebral/metabolismo , Terapia Genética , Humanos , Metaloendopeptidases/biossíntese , Metaloendopeptidases/genética , Camundongos , Proteínas do Tecido Nervoso/biossíntese , Proteínas do Tecido Nervoso/genética , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/patologia , Neurotoxinas/farmacologia , Bulbo Olfatório/metabolismo , Estresse Oxidativo , Oxigênio/farmacologia , Ratos , Proteínas Recombinantes/metabolismo , Sistema Renina-Angiotensina/fisiologia , Acidente Vascular Cerebral/fisiopatologia , Acidente Vascular Cerebral/terapia , Regulação para Cima
5.
Biomed Res Int ; 2019: 7654798, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31309116

RESUMO

This study aimed to screen the target miRNAs and to investigate the differential miR-3557/324-targeted signal mechanisms in the rats' model of Parkinson's disease (PD) with regular aerobic exercise. Rats were divided into sedentary control PD group (SED-PD, n = 18) and aerobic exercise PD group (EX-PD, n = 22). After 8 weeks of regular aerobic exercise, a 6-hydroxydopamine- (6-OHDA-) induced PD lesion model was constructed. Preregular aerobic exercises enhanced the injury resistance of rats with 6-OHDA-induced PD. The rotational behavior after injection of apomorphine hydrochloride was alleviated. Under the scanning electron microscopy, we found the neurons, axons, and villi of the striatum were clearly and tightly arranged, and neurons and axons significantly becoming larger. Tyrosine hydroxylase (TH) was increased significantly and α-synuclein protein expression was reduced in the EX-PD group compared to the SED-PD group. Screening from miRNA microarray chip, we further found upregulation of miR-3557 and downregulation of miR-324 were closely related to the calcium-modulating signaling pathway, remitting the progress of Parkinson's disease on aerobic exercise. Compared to the SED-PD group, Ca2+/calmodulin dependent protein kinase II (CaMK2α) was upregulated, but CaMKV and voltage-dependent anion-selective channel protein 1 (Vdac1) were significantly downregulated in the EX-PD group. Additionally, phosphatidylinositol-3-kinase (PI3K)/mammalian target of rapamycin (mTOR) expression were activated, and ubiquitin carboxy-terminal hydrolase L1 (UCH-L1) expression was upregulated in the EX-PD group. Conclusions: the adaptive mechanism of regular aerobic exercise delaying neurodegenerative diseases and lesions was that miR-3557/324 was activated to regulate one of its targets CaMKs signaling pathways. CaMKs, coordinated with mTOR pathway-related gene expression, improved UCH-L1 level to favor for delaying neurodegeneration or improving the pathogenesis of PD lesions.


Assuntos
Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/biossíntese , Proteínas de Ligação a Calmodulina/biossíntese , Corpo Estriado/metabolismo , Regulação da Expressão Gênica , MicroRNAs/biossíntese , Proteínas do Tecido Nervoso/biossíntese , Doença de Parkinson Secundária/metabolismo , Condicionamento Físico Animal , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo , Animais , Corpo Estriado/patologia , Corpo Estriado/fisiopatologia , Perfilação da Expressão Gênica , Masculino , Doença de Parkinson Secundária/patologia , Doença de Parkinson Secundária/fisiopatologia , Ratos , Ratos Sprague-Dawley
6.
Neuron ; 103(4): 598-616.e7, 2019 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-31248728

RESUMO

Dorsal root ganglion (DRG) sensory neuron subtypes defined by their in vivo properties display distinct intrinsic electrical properties. We used bulk RNA sequencing of genetically labeled neurons and electrophysiological analyses to define ion channel contributions to the intrinsic electrical properties of DRG neuron subtypes. The transcriptome profiles of eight DRG neuron subtypes revealed differentially expressed and functionally relevant genes, including voltage-gated ion channels. Guided by these data, electrophysiological analyses using pharmacological and genetic manipulations as well as computational modeling of DRG neuron subtypes were undertaken to assess the functions of select voltage-gated potassium channels (Kv1, Kv2, Kv3, and Kv4) in shaping action potential (AP) waveforms and firing patterns. Our findings show that the transcriptome profiles have predictive value for defining ion channel contributions to sensory neuron subtype-specific intrinsic physiological properties. The distinct ensembles of voltage-gated ion channels predicted to underlie the unique intrinsic physiological properties of eight DRG neuron subtypes are presented.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala , Canais Iônicos/fisiologia , Células Receptoras Sensoriais/fisiologia , Potenciais de Ação , Vias Aferentes/fisiologia , Animais , Simulação por Computador , Gânglios Espinais/citologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Canais Iônicos/biossíntese , Canais Iônicos/genética , Mecanorreceptores/fisiologia , Camundongos , Camundongos Transgênicos , Modelos Neurológicos , Proteínas do Tecido Nervoso/biossíntese , Proteínas do Tecido Nervoso/genética , Técnicas de Patch-Clamp , Canais de Potássio de Abertura Dependente da Tensão da Membrana/fisiologia , RNA/genética , Células Receptoras Sensoriais/química , Células Receptoras Sensoriais/classificação , Transcriptoma
7.
Nat Neurosci ; 22(7): 1066-1074, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31209380

RESUMO

Cannabis is the most frequently used illicit psychoactive substance worldwide; around one in ten users become dependent. The risk for cannabis use disorder (CUD) has a strong genetic component, with twin heritability estimates ranging from 51 to 70%. Here we performed a genome-wide association study of CUD in 2,387 cases and 48,985 controls, followed by replication in 5,501 cases and 301,041 controls. We report a genome-wide significant risk locus for CUD (P = 9.31 × 10-12) that replicates in an independent population (Preplication = 3.27 × 10-3, Pmeta-analysis = 9.09 × 10-12). The index variant (rs56372821) is a strong expression quantitative trait locus for cholinergic receptor nicotinic α2 subunit (CHRNA2); analyses of the genetically regulated gene expression identified a significant association of CHRNA2 expression with CUD in brain tissue. At the polygenic level, analyses revealed a significant decrease in the risk of CUD with increased load of variants associated with cognitive performance. The results provide biological insights and inform on the genetic architecture of CUD.


Assuntos
Abuso de Maconha/genética , Proteínas do Tecido Nervoso/fisiologia , Receptores Nicotínicos/fisiologia , Idade de Início , Alelos , Transtorno do Deficit de Atenção com Hiperatividade/genética , Encéfalo/metabolismo , Estudos de Casos e Controles , Cromossomos Humanos Par 8/genética , Cognição/fisiologia , Estudos de Coortes , Dinamarca , Escolaridade , Feminino , Perfilação da Expressão Gênica , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Islândia , Masculino , Herança Multifatorial , Proteínas do Tecido Nervoso/biossíntese , Proteínas do Tecido Nervoso/genética , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Receptores Nicotínicos/biossíntese , Receptores Nicotínicos/genética , Esquizofrenia/genética , Fumar/genética , Transcriptoma
8.
Stroke ; 50(7): 1850-1858, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31167620

RESUMO

Background and Purpose- Ischemic stroke is one of the leading causes of morbidity and mortality worldwide and a major cause of long-term disability. Recently, long noncoding RNAs have been revealed, which are tightly associated with several human diseases. However, the functions of long noncoding RNAs in ischemic stroke still remain largely unknown. In the current study, for the first time, we investigated the role of long noncoding RNA Nespas in ischemic stroke. Methods- We used in vivo models of middle cerebral artery occlusion and in vitro models of oxygen-glucose deprivation to illustrate the effect of long noncoding RNA Nespas on ischemic stroke. Results- We found expression of Nespas was significantly increased in ischemic cerebral tissues and oxygen-glucose deprivation-treated BV2 cells in a time-dependent manner. Silencing of Nespas aggravated middle cerebral artery occlusion operation-induced IR injury and cell death. In addition, proinflammatory cytokine production and NF-κB (nuclear factor-κB) signaling activation were inhibited by Nespas overexpression. TAK1 (transforming growth factor-ß-activated kinase 1) was found to directly interact with Nespas, and TAK1 activation was significantly suppressed by Nespas. At last, we found Nespas-inhibited TRIM8 (tripartite motif 8)-induced K63-linked polyubiquitination of TAK1. Conclusions- We showed that Nespas played anti-inflammatory and antiapoptotic roles in cultured microglial cells after oxygen-glucose deprivation stimulation and in mice after ischemic stroke by inhibiting TRIM8-related K63-linked polyubiquitination of TAK1.


Assuntos
Isquemia Encefálica/patologia , Morte Celular , Inativação Gênica , Inflamação/patologia , Microglia/patologia , RNA Longo não Codificante/genética , Acidente Vascular Cerebral/patologia , Animais , Células Cultivadas , Citocinas/metabolismo , Humanos , Infarto da Artéria Cerebral Média/patologia , MAP Quinase Quinase Quinases/biossíntese , MAP Quinase Quinase Quinases/genética , Camundongos , Proteínas do Tecido Nervoso/biossíntese , Proteínas do Tecido Nervoso/genética , Ubiquitina-Proteína Ligases/biossíntese , Ubiquitina-Proteína Ligases/genética , Ubiquitinação/genética
9.
J Neurol ; 266(9): 2273-2276, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31168673

RESUMO

OBJECTIVE: The efficacy of levetiracetam (LEV) in controlling seizures in patients with brain tumor-related epilepsy (BTRE) depends on tumoral expression of synaptic vesicle protein 2A (SV2A). Although LEV is generally well tolerated, neuropsychiatric adverse events (NPAEs) might occur, limiting compliance and seizure control. We aimed to assess the influence of tumoral SV2A expression on the occurrence of LEV-related NPAEs in patients with glioma. METHODS: Specimens from patients enrolled in the multicenter COMPO study, with glioma and BTRE treated with LEV, undergoing neurosurgery were retrieved. Immunohistochemistry-based expression of SV2A in tumoral and peritumoral tissue was scored in a four-point scale from absent (score = 0) to strong (score = 3). Low immunoreactivity (IR) corresponded to scores < 2. Staining ratios (tumoral SV2A IR/peritumoral SV2A IR) were grouped into low (≤ 0.5) and high (> 0.5). NPAEs were assessed longitudinally with the Neuropsychiatry Inventory 12 test (NPI-12). RESULTS: Overall, 18 patients were eligible for analysis. All received LEV monotherapy, with 67% developing NPAEs. Patients with NPAEs had significantly lower median SV2A intensity score compared to patients without NPAEs (score 1 vs 0, p = 0.025). Low staining ratio (≤ 0.5) associated with higher NPAE occurrence compared to SR > 0.5 (85.7% vs 0%, p < 0.01). A SR ≤ 0.5 predicted a consistent increase in risk of NPAEs (OR 45.0; 95% CI 1.8-1128; p = 0.02). CONCLUSIONS: Our results suggest that SV2A expression in tumoral and peritumoral tissue correlates with the occurrence of LEV-related NPAEs. Thus, considering that SV2A expression also influences LEV effectiveness, SV2A staining might help in tailoring treatment to patients.


Assuntos
Anticonvulsivantes/uso terapêutico , Neoplasias Encefálicas/metabolismo , Epilepsia/metabolismo , Levetiracetam/uso terapêutico , Glicoproteínas de Membrana/biossíntese , Proteínas do Tecido Nervoso/biossíntese , Adulto , Idoso , Anticonvulsivantes/efeitos adversos , Biomarcadores/metabolismo , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/genética , Epilepsia/tratamento farmacológico , Epilepsia/genética , Feminino , Expressão Gênica , Humanos , Levetiracetam/efeitos adversos , Masculino , Glicoproteínas de Membrana/genética , Transtornos Mentais/induzido quimicamente , Transtornos Mentais/genética , Transtornos Mentais/metabolismo , Pessoa de Meia-Idade , Proteínas do Tecido Nervoso/genética , Valor Preditivo dos Testes , Estudos Prospectivos
10.
Neuron ; 103(4): 702-718.e5, 2019 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-31227310

RESUMO

The locus coeruleus (LC) supplies norepinephrine (NE) to the entire forebrain and regulates many fundamental brain functions. Studies in humans have suggested that strong LC activation might shift network connectivity to favor salience processing. To causally test this hypothesis, we use a mouse model to study the effect of LC stimulation on large-scale functional connectivity by combining chemogenetic activation of the LC with resting-state fMRI, an approach we term "chemo-connectomics." We show that LC activation rapidly interrupts ongoing behavior and strongly increases brain-wide connectivity, with the most profound effects in the salience and amygdala networks. Functional connectivity changes strongly correlate with transcript levels of alpha-1 and beta-1 adrenergic receptors across the brain, and functional network connectivity correlates with NE turnover within select brain regions. We propose that these changes in large-scale network connectivity are critical for optimizing neural processing in the context of increased vigilance and threat detection.


Assuntos
Conectoma , Locus Cerúleo/fisiologia , Receptores Adrenérgicos alfa 1/fisiologia , Receptores Adrenérgicos beta 1/fisiologia , Animais , Ansiedade/fisiopatologia , Clozapina/farmacologia , Corpo Estriado/metabolismo , Drogas Desenhadas/farmacologia , Dopamina/metabolismo , Comportamento Exploratório/fisiologia , Neuroimagem Funcional , Genes fos , Locus Cerúleo/efeitos dos fármacos , Imagem por Ressonância Magnética , Masculino , Camundongos , Camundongos Transgênicos , Rede Nervosa/fisiologia , Proteínas do Tecido Nervoso/biossíntese , Proteínas do Tecido Nervoso/genética , Norepinefrina/metabolismo , Proteínas Proto-Oncogênicas c-fos/biossíntese , Proteínas Proto-Oncogênicas c-fos/genética , Receptores Adrenérgicos alfa 1/biossíntese , Receptores Adrenérgicos alfa 1/genética , Receptores Adrenérgicos beta 1/biossíntese , Receptores Adrenérgicos beta 1/genética , Receptores de Droga/fisiologia , Teste de Desempenho do Rota-Rod , Regulação para Cima/efeitos dos fármacos
11.
Nucleic Acids Res ; 47(13): e77, 2019 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-31045217

RESUMO

The availability of genome-wide epigenomic datasets enables in-depth studies of epigenetic modifications and their relationships with chromatin structures and gene expression. Various alignment tools have been developed to align nucleotide or protein sequences in order to identify structurally similar regions. However, there are currently no alignment methods specifically designed for comparing multi-track epigenomic signals and detecting common patterns that may explain functional or evolutionary similarities. We propose a new local alignment algorithm, EpiAlign, designed to compare chromatin state sequences learned from multi-track epigenomic signals and to identify locally aligned chromatin regions. EpiAlign is a dynamic programming algorithm that novelly incorporates varying lengths and frequencies of chromatin states. We demonstrate the efficacy of EpiAlign through extensive simulations and studies on the real data from the NIH Roadmap Epigenomics project. EpiAlign is able to extract recurrent chromatin state patterns along a single epigenome, and many of these patterns carry cell-type-specific characteristics. EpiAlign can also detect common chromatin state patterns across multiple epigenomes, and it will serve as a useful tool to group and distinguish epigenomic samples based on genome-wide or local chromatin state patterns.


Assuntos
Cromatina/ultraestrutura , Biologia Computacional/métodos , Epigenômica/métodos , Alinhamento de Sequência , Algoritmos , Sequência de Bases , Química Encefálica , Cromatina/genética , Metilação de DNA , Bases de Dados Genéticas , Conjuntos de Dados como Assunto , Ontologia Genética , Humanos , Proteínas do Tecido Nervoso/biossíntese , Proteínas do Tecido Nervoso/química , Proteínas do Tecido Nervoso/genética , Software
12.
Biotechnol Lett ; 41(6-7): 873-887, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31073804

RESUMO

OBJECTIVE: Human dental pulp-derived stem cells (hDPSCs) are becoming an attractive source for cell-based neurorestorative therapies. As such, it is important to understand the molecular mechanisms that regulate the differentiation of hDPSCs toward the neuronal fate. Notch signaling plays key roles in neural stem/progenitor cells (NS/PCs) maintenance and prevention of their differentiation. The aim of this study was to address the effects of Notch signaling inhibition on neurosphere formation of hDPSCs and neuronal differentiation of hDPSCs-neurospheres. RESULTS: hDPSCs were isolated from third molar teeth. The cultivated hDPSCs highly expressed CD90 and CD44 and minimally presented CD34 and CD45 surface markers. The osteo/adipogenic differentiation of hDPSCs was documented. hDPSCs were cultured in neural induction medium and N-[N-(3,5-difluorophenacetyl-L-alanyl)]-Sphenylglycine t-butyl ester (DAPT) was applied to impede Notch signaling during transformation into spheres or on the formed neurospheres. Our results showed that the size and number of neurospheres decreased and the expression profile of nestin, sox1 and pax6 genes reduced provided DAPT. Treatment of the formed neurospheres with DAPT resulted in the cleaved Notch1 reduction, G0/G1 arrest and a decline in L-lactate production. DAPT significantly reduced hes1 and hey1 genes, while ascl1 and neurogenin2 expressions augmented. The number of MAP2 positive cells improved in the DAPT-treated group. CONCLUSIONS: Our findings demonstrated the Notch activity in hDPSCs-neurospheres. DAPT treatment positively regulated proneural genes expression and increased neuronal-like differentiation.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/biossíntese , Pontos de Checagem do Ciclo Celular , Diferenciação Celular/efeitos dos fármacos , Inibidores Enzimáticos/metabolismo , Proteínas do Tecido Nervoso/biossíntese , Células-Tronco Neurais/efeitos dos fármacos , Receptores Notch/antagonistas & inibidores , Células Cultivadas , Polpa Dentária , Expressão Gênica , Humanos
13.
Elife ; 82019 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-31099332

RESUMO

Direct conversion of human somatic fibroblasts into induced neurons (iNs) allows for the generation of functional neurons while bypassing any stem cell intermediary stages. Although iN technology has an enormous potential for modeling age-related diseases, as well as therapeutic approaches, the technology faces limitations due to variable conversion efficiencies and a lack of thorough understanding of the signaling pathways directing iN conversion. Here, we introduce a new all-in-one inducible lentiviral system that simplifies fibroblast transgenesis for the two pioneer transcription factors, Ngn2 and Ascl1, and markedly improves iN yields. Further, our timeline RNA-Seq data across the course of conversion has identified signaling pathways that become transcriptionally enriched during iN conversion. Small molecular modulators were identified for four signaling pathways that reliably increase the yield of iNs. Taken together, these advances provide an improved toolkit for iN technology and new insight into the mechanisms influencing direct iN conversion.


Assuntos
Transdiferenciação Celular , Fibroblastos/efeitos dos fármacos , Fibroblastos/fisiologia , Neurônios/fisiologia , Transdução de Sinais/efeitos dos fármacos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/biossíntese , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Células Cultivadas , Criança , Pré-Escolar , Perfilação da Expressão Gênica , Técnicas de Transferência de Genes , Humanos , Lactente , Recém-Nascido , Pessoa de Meia-Idade , Proteínas do Tecido Nervoso/biossíntese , Proteínas do Tecido Nervoso/genética , Análise de Sequência de RNA , Adulto Jovem
14.
Biomed Res Int ; 2019: 1431760, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30949496

RESUMO

Repetitive transcranial magnetic stimulation (rTMS) is a noninvasive and painless technique that has been applied for the treatments of diverse neurodegenerative disorders. In the current study, its anti-Alzheimer's disease (AD) effect was assessed and the mechanism driving the effect was explored. The AD symptoms were induced via the intracranial injection of Aß 1-42 in mice and then treated with rTMS of 1 Hz or 10 Hz. The anti-AD effect of rTMS was assessed by Morris water maze (MWM), histological staining and western blotting. The results showed that rTMS administrations of both frequencies improved the cognitive function and suppressed neuron apoptosis in AD mice. Moreover, the treatment also increased the brain BDNF, NGF, and doublecortin levels, which represented the increased viability of neurons by rTMS. The injection of Aß 1-42 also increased the expressions of p-GSK-3ß, p-Tau, and p-ß-catenin and suppressed the level of total ß-catenin. After the treatments of rTMS, the level of ß-catenin was restored, indicating the activation of ß-catenin signaling. In conclusion, the findings outlined in the current study demonstrated that the anti-AD effect of rTMS was associated with the activation of ß-catenin, which would promote the survival of neurons.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides/toxicidade , Encéfalo , Fragmentos de Peptídeos/toxicidade , Transdução de Sinais , Estimulação Magnética Transcraniana , beta Catenina/metabolismo , Doença de Alzheimer/induzido quimicamente , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Doença de Alzheimer/terapia , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Regulação da Expressão Gênica , Humanos , Masculino , Camundongos , Proteínas do Tecido Nervoso/biossíntese
15.
Glia ; 67(7): 1333-1343, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30889310

RESUMO

Neural progenitor cells (NPCs) are sequentially specified into neurons and glia during the development of central nervous system. WNT/ß-catenin signaling is known to regulate the balance between the proliferation and differentiation of NPCs during neurogenesis. However, the function of WNT/ß-catenin signaling during gliogenesis remains poorly defined. Here, we report that activation of WNT/ß-catenin signaling disrupts astrogliogenesis in the developing spinal cord. Conversely, inhibition of WNT/ß-catenin signaling leads to precocious astrogliogenesis. Further analysis reveals that activation of WNT/ß-catenin pathway results in a dramatic increase of neurogenin 2 (Ngn2) expression in transgenic mice, and knockdown of Ngn2 expression in neural precursor cells can reverse the inhibitory effect of WNT/ß-catenin on astrocytic differentiation. Moreover, Ngn2 can directly bind to the promoters of several astrocyte specific genes and suppress their expression independent of STATs activity. Together, our studies provide the first in vivo evidence that WNT/ß-catenin signaling inhibits early astrogliogenesis via an Ngn2-dependent transcriptional repression mechanism.


Assuntos
Astrócitos/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/biossíntese , Diferenciação Celular/fisiologia , Proteínas do Tecido Nervoso/biossíntese , Neurogênese/fisiologia , Via de Sinalização Wnt/fisiologia , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Feminino , Expressão Gênica , Células HEK293 , Humanos , Masculino , Camundongos , Camundongos Transgênicos , Proteínas do Tecido Nervoso/genética
16.
Neuroscience ; 406: 126-139, 2019 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-30825582

RESUMO

Ethanol ingestion by a mother during pregnancy entails adverse consequences for her offspring. In this study, adult female rats were given access to ethanol from 8 days prior to mating to post-parturition weaning, and the effects on her offspring were evaluated. We investigated changes in the cocaine- and amphetamine-regulated transcript peptide (CART), a neuropeptide involved in the central effects of ethanol in the frame of reward and stress processing circuits. CART-immunoreactivity was augmented in the cells of Edinger-Westphal (EW) nucleus and lateral hypothalamus (LH) and fibers in the LH and ventral tegmental area (VTA) in 25-day-old pups. On the other hand, a significant decrease was seen in the expression of the peptide in paraventricular nucleus (PVN), arcuate nucleus (ARC), hippocampus (CA1 and CA2) and locus coeruleus (LC). The offspring at 85 days showed increased anxiety in elevated plus maze and immobility in forced swim test suggestive of depression. These rats also failed to discriminate between novel versus familiar object in object recognition test indicating memory deficits. Their brains showed decreased CART-immunoreactivity in nucleus accumbens shell, lateral bed nucleus of stria terminalis, PVN, ARC, LH, hippocampus and LC as compared to age-matched control offspring. However, CART-immunoreactive profile in EW and fibers in VTA of 85-day-old offspring was similar to that in the control. Thus, regional imbalance in the CART system of the offspring of alcoholic dams seems correlated with the affective and emotional abnormalities and memory deficits.


Assuntos
Ansiedade/metabolismo , Encéfalo/metabolismo , Depressão/metabolismo , Etanol/efeitos adversos , Transtornos da Memória/metabolismo , Proteínas do Tecido Nervoso/biossíntese , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Animais , Ansiedade/induzido quimicamente , Encéfalo/efeitos dos fármacos , Depressão/induzido quimicamente , Etanol/administração & dosagem , Feminino , Masculino , Transtornos da Memória/induzido quimicamente , Gravidez , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Ratos , Ratos Sprague-Dawley
17.
Mol Cell Biochem ; 457(1-2): 51-59, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30830528

RESUMO

Exosomes are nanometer-sized vesicles involved in intercellular communication, and they are released by various cell types. To learn about exosomes produced by Schwann cells (SCs) and to explore their potential function in repairing the central nervous system (CNS), we isolated exosomes from supernatants of SCs by ultracentrifugation, characterized them by electron microscopy and immunoblotting and determined their protein profile using proteomic analysis. The results demonstrated that Schwann cell-derived exosomes (SCDEs) were, on average, 106.5 nm in diameter, round, and had cup-like concavity and expressed exosome markers CD9 and Alix but not tumor susceptibility gene (TSG) 101. We identified a total of 433 proteins, among which 398 proteins overlapped with the ExoCarta database. According to their specific functions, we identified 12 proteins that are closely related to CNS repair and classified them by different potential mechanisms, such as axon regeneration and inflammation inhibition. Gene Oncology analysis indicated that SCDEs are mainly involved in signal transduction and cell communication. Biological pathway analysis showed that pathways are mostly involved in exosome biogenesis, formation, uptake and axon regeneration. Among the pathways, the neurotrophin, PI3K-Akt and cAMP signaling pathways played important roles in CNS repair. Our study isolated SCDEs, unveiled their contents, presented potential neurorestorative proteins and pathways and provided a rich proteomics data resource that will be valuable for future studies of the functions of individual proteins in neurodegenerative diseases.


Assuntos
Exossomos/metabolismo , Proteínas do Tecido Nervoso/biossíntese , Proteômica , Células de Schwann/metabolismo , Nervo Isquiático/lesões , Nervo Isquiático/metabolismo , Animais , Biomarcadores/metabolismo , Exossomos/patologia , Masculino , Ratos , Ratos Wistar , Células de Schwann/patologia , Nervo Isquiático/patologia
18.
Toxicol Lett ; 306: 1-10, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30742882

RESUMO

Chronic lead (Pb) exposure has been shown to reduce the expression of some synaptic proteins which are involved in vesicular trafficking and affect presynaptic neurotransmitter release. However, the precise mechanisms by Pb impairs neurotransmitter release are still not well defined. In the current study, we aimed to elucidate the changes of Huntingtin-associated protein 1 (HAP1) in Pb exposed rats and PC12 cells models and its molecular mechanism. Repressor element-1 silencing transcription (REST) modulates the expression of genes containing the repressor element 1 (RE-1) cis-regulatory DNA sequence. HAP1 promoter region contains a RE-1 binding motif. We also observed whether Pb exposure regulated the HAP1 transcription level through influencing the expression of REST. Mother rats were exposed to 0.5 and 2 g/L Pb acetate (PbAc) in drinking water from the first day of gestation until postnatal 21 days, then the offspring rats were continued to drink PbAc for 1 year, while the control groups received drinking water. PC12 cells were divided into 3 groups: 0 µM, 1 µM and 100 µM PbAc. The results revealed that Pb levels in blood and brain of Pb exposed groups were significantly higher than that of the control group. The ability of learning and memory in Pb exposed rats was decreased. Pb exposure reduced the expression of HAP1 and increased the REST expression. Silencing REST could reverse the decreasing of HAP1 in Pb exposed PC12 cells. Our findings raise a possibility that the decreasing of HAP1 expression by Pb exposure may affect neurotransmitter release and results in impairments in spatial learning and memory ability.


Assuntos
Intoxicação por Chumbo/metabolismo , Proteínas do Tecido Nervoso/biossíntese , Proteínas do Tecido Nervoso/efeitos dos fármacos , Correpressor 1 de Receptor Nuclear/efeitos dos fármacos , Proteínas Repressoras/biossíntese , Proteínas Repressoras/efeitos dos fármacos , Animais , Encéfalo/metabolismo , Feminino , Expressão Gênica/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Humanos , Chumbo/sangue , Chumbo/metabolismo , Intoxicação por Chumbo/genética , Intoxicação por Chumbo/psicologia , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Memória/efeitos dos fármacos , Células PC12 , Gravidez , RNA Interferente Pequeno/farmacologia , Ratos , Ratos Sprague-Dawley , Proteínas Repressoras/genética
19.
Medicine (Baltimore) ; 98(7): e13298, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30762724

RESUMO

INTRODUCTION: SEMA4D and its high affinity receptor Plexin-B1 showed a promising prognosis prediction for carcinoma patients in recent studies, we performed a meta-analysis to evaluate the prognostic role of them in various malignancies. METHODS: A systematic literature search was performed in PubMed, Embase, Web of Science, and CNKI from inception till July 2017. Eligible studies were identified by different reviewers. Hazard ratios (HRs)/related ratios (RRs) and their corresponding 95% confidence intervals (CIs) were extracted to investigate the relevance between malignancies prognosis and SEMA4D/Plexin-B1. RESULTS: Around 2638 patients from 14 studies were included in this meta-analysis. High expression of SEMA4D was significantly associated with overall survival (OS) and disease-free survival/progression-free survival/recurrence-free survival (DFS/PFS/RFS) in tumors (respectively, HRos = 2.05, 95%CI: 1.68-2.50, P < .001; HRdfs/pfs/rfs = 1.59, 95%CI = 1.27-1.98, P < .001). However, the relationship between SEMA4D expression and prognosis of breast cancer patients was failed to find (HR = 0.76, 95%CI = 0.32-1.82, P = .539). Plexin-B1 level showed a significant positive correlation both with OS and DFS of Caucasian breast cancer patients (respectively, HRos = 0.56, 95%CI: 0.39-0.79, P = .001; HRdfs = 0.68, 95%CI = 0.51-0.90, P = .008) CONCLUSIONS:: SEMA4D could be a prospective biomarker for prognostic prediction of various malignancies except breast cancer. For Caucasian breast cancer patients, SEMA4D's high affinity receptor Plexin-B1 showed a significant positive correlation with survival.


Assuntos
Antígenos CD/biossíntese , Neoplasias/genética , Neoplasias/mortalidade , Proteínas do Tecido Nervoso/biossíntese , Receptores de Superfície Celular/biossíntese , Semaforinas/biossíntese , Biomarcadores Tumorais , Neoplasias da Mama/genética , Intervalo Livre de Doença , Humanos , Prognóstico , Modelos de Riscos Proporcionais , Estudos Prospectivos
20.
Int J Med Sci ; 16(1): 115-124, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30662335

RESUMO

Background: The magic roundabout receptor 4 (Robo 4) is a tumor endothelial marker expressed in the vascular network of various tumor entities. However, the role of Robo 4 in prostate cancer (PCa), the second common cause of cancer death among men in -developed countries, has not been described yet. Thus, the present study investigates for the first time the impact of Robo 4 in PCa both in the clinical setting and in vitro. Methods and Results: Immunohistochemical analyses of benign and malignant prostate tissue samples of 95 PCa patients, who underwent radical prostatectomy (RPE), revealed a significant elevated expression of Robo 4 as well as its ligand Slit 2 protein in cancerous tissue compared to benign. Moreover, increased Robo 4 expression was associated with higher Gleason score and pT stage. In advanced stage we observed a hypothesis-generating trend that high Robo 4 and Slit 2 expression is associated with delayed development of tumor recurrence compared to patients with low Robo 4 and Slit 2 expression, respectively. In contrast to so far described exclusive expression of Robo 4 in the tumor vascular network, our analyses showed that in PCa Robo 4 is not only expressed in the tumor stroma but also in cancer epithelial cells. This finding was also confirmed in vitro as PC3 PCa cells express Robo 4 on mRNA as well as protein level. Overexpression of Robo 4 in PC3 as well as in Robo 4 negative DU145 and LNCaP PCa cells was associated with a significant decrease in cell-proliferation and cell-viability. Conclusion: In summary we observed that Robo 4 plays a considerable role in PCa development as it is expressed in cancer epithelial cells as well as in the surrounding tumor stroma. Moreover, higher histological tumor grade was associated with increased Robo 4 expression; controversially patients with high Robo 4 tend to exert lower biochemical recurrence possibly reflecting a protective role of Robo 4.


Assuntos
Peptídeos e Proteínas de Sinalização Intercelular/biossíntese , Proteínas do Tecido Nervoso/biossíntese , Neoplasias da Próstata , Receptores de Superfície Celular/biossíntese , Idoso , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Neovascularização Patológica , Prognóstico , Neoplasias da Próstata/irrigação sanguínea , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Transcriptoma
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