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1.
Biomed Res Int ; 2021: 1601565, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34604381

RESUMO

Trogocytosis is a general biological process that involves one cell physically taking small parts of the membrane and other components from another cell. In trogocytosis, one cell seems to take little "bites" from another cell resulting in multiple outcomes from these cell-cell interactions. Trogocytosis was first described in protozoan parasites, which by taking pieces of host cells, kill them and cause tissue damage. Now, it is known that this process is also performed by cells of the immune system with important consequences such as cell communication and activation, elimination of microbial pathogens, and even control of cancer cells. More recently, trogocytosis has also been reported to occur in cells of the central nervous system and in various cells during development. Some of the molecules involved in phagocytosis also participate in trogocytosis. However, the molecular mechanisms that regulate trogocytosis are still a mystery. Elucidating these mechanisms is becoming a research area of much interest. For example, why neutrophils can engage trogocytosis to kill Trichomonas vaginalis parasites, but neutrophils use phagocytosis to eliminate already death parasites? Thus, trogocytosis is a significant process in normal physiology that multiple cells from different organisms use in various scenarios of health and disease. In this review, we present the basic principles known on the process of trogocytosis and discuss the importance in this process to host-pathogen interactions and to normal functions in the immune and nervous systems.


Assuntos
Crescimento e Desenvolvimento , Imunidade , Sistema Nervoso/citologia , Trogocitose/imunologia , Animais , Bactérias/metabolismo , Morte Celular , Humanos
2.
Int J Mol Sci ; 22(5)2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33807555

RESUMO

Although the human brain would be an ideal model for studying human neuropathology, it is difficult to perform in vitro culture of human brain cells from genetically engineered healthy or diseased brain tissue. Therefore, a suitable model for studying the molecular mechanisms responsible for neurological diseases that can appropriately mimic the human brain is needed. Somatic cell nuclear transfer (SCNT) was performed using an established porcine Yucatan EGFP cell line and whole seeding was performed using SCNT blastocysts. Two Yucatan EGFP porcine embryonic stem-like cell (pESLC) lines were established. These pESLC lines were then used to establish an in vitro neuro-organoids. Aggregates were cultured in vitro until 61 or 102 days after neural induction, neural patterning, and neural expansion. The neuro-organoids were sampled at each step and the expression of the dopaminergic neuronal marker (TH) and mature neuronal marker (MAP2) was confirmed by reverse transcription-PCR. Expression of the neural stem cell marker (PAX6), neural precursor markers (S100 and SOX2), and early neural markers (MAP2 and Nestin) were confirmed by immunofluorescence staining. In conclusion, we successfully established neuro-organoids derived from pESLCs in vitro. This protocol can be used as a tool to develop in vitro models for drug development, patient-specific chemotherapy, and human central nervous system disease studies.


Assuntos
Células-Tronco Embrionárias/citologia , Organoides/citologia , Animais , Biomarcadores/metabolismo , Blastocisto/citologia , Blastocisto/metabolismo , Linhagem Celular , Células-Tronco Embrionárias/metabolismo , Fibroblastos/citologia , Fibroblastos/metabolismo , Camundongos , Camundongos Endogâmicos ICR , Sistema Nervoso/citologia , Sistema Nervoso/metabolismo , Técnicas de Transferência Nuclear , Organoides/metabolismo , Suínos
3.
FEBS J ; 288(1): 99-110, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32307851

RESUMO

How evolutionary novelties have arisen is one of the central questions in evolutionary biology. Preexisting gene regulatory networks or signaling pathways have been shown to be co-opted for building novel traits in several organisms. However, the structure of entire gene regulatory networks and evolutionary events of gene co-option for emergence of a novel trait are poorly understood. In this study, to explore the genetic and molecular bases of the novel wing pigmentation pattern of a polka-dotted fruit fly (Drosophila guttifera), we performed de novo genome sequencing and transcriptome analyses. As a result, we comprehensively identified the genes associated with the pigmentation pattern. Furthermore, we revealed that 151 of these associated genes were positively or negatively regulated by wingless, a master regulator of wing pigmentation. Genes for neural development, Wnt signaling, Dpp signaling, and effectors (such as enzymes) for melanin pigmentation were included among these 151 genes. None of the known regulatory genes that regulate pigmentation pattern formation in other fruit fly species were included. Our results suggest that the novel pigmentation pattern of a polka-dotted fruit fly might have emerged through multistep co-options of multiple gene regulatory networks, signaling pathways, and effector genes, rather than recruitment of one large gene circuit.


Assuntos
Proteínas de Drosophila/genética , Drosophila/genética , Neurogênese/genética , Pigmentação/genética , Transcriptoma , Asas de Animais/metabolismo , Proteína Wnt1/genética , Animais , Evolução Biológica , Drosophila/crescimento & desenvolvimento , Drosophila/metabolismo , Proteínas de Drosophila/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Redes Reguladoras de Genes , Melaninas/genética , Melaninas/metabolismo , Sistema Nervoso/citologia , Sistema Nervoso/crescimento & desenvolvimento , Sistema Nervoso/metabolismo , Fenótipo , Transdução de Sinais , Asas de Animais/crescimento & desenvolvimento , Proteínas Wnt/genética , Proteínas Wnt/metabolismo , Proteína Wnt1/metabolismo
4.
Sci Rep ; 10(1): 18746, 2020 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-33127972

RESUMO

Dendrites, branched structures extending from neuronal cell soma, are specialized for processing information from other neurons. The morphogenesis of dendritic structures is spatiotemporally regulated by well-orchestrated signaling cascades. Dysregulation of these processes impacts the wiring of neuronal circuit and efficacy of neurotransmission, which contribute to the pathogeneses of neurological disorders. While Cdk5 (cyclin-dependent kinase 5) plays a critical role in neuronal dendritic development, its underlying molecular control is not fully understood. In this study, we show that p39, one of the two neuronal Cdk5 activators, is a key regulator of dendritic morphogenesis. Pyramidal neurons deficient in p39 exhibit aberrant dendritic morphology characterized by shorter length and reduced arborization, which is comparable to dendrites in Cdk5-deficient neurons. RNA sequencing analysis shows that the adaptor protein, WDFY1 (WD repeat and FYVE domain-containing 1), acts downstream of Cdk5/p39 to regulate dendritic morphogenesis. While WDFY1 is elevated in p39-deficient neurons, suppressing its expression rescues the impaired dendritic arborization. Further phosphoproteomic analysis suggests that Cdk5/p39 mediates dendritic morphogenesis by modulating various downstream signaling pathways, including PI3K/Akt-, cAMP-, or small GTPase-mediated signaling transduction pathways, thereby regulating cytoskeletal organization, protein synthesis, and protein trafficking.


Assuntos
Quinase 5 Dependente de Ciclina/metabolismo , Proteínas do Citoesqueleto/metabolismo , Dendritos/metabolismo , Proteínas Ligadas a Lipídeos/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Western Blotting , Diferenciação Celular/genética , Diferenciação Celular/fisiologia , AMP Cíclico/metabolismo , Quinase 5 Dependente de Ciclina/genética , Proteínas do Citoesqueleto/genética , Células HEK293 , Humanos , Proteínas Ligadas a Lipídeos/genética , Espectrometria de Massas , Camundongos , Proteínas Monoméricas de Ligação ao GTP/genética , Proteínas Monoméricas de Ligação ao GTP/metabolismo , Morfogênese/genética , Morfogênese/fisiologia , Sistema Nervoso/citologia , Sistema Nervoso/metabolismo , Neurônios/metabolismo , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Transdução de Sinais/genética , Transdução de Sinais/fisiologia , Transmissão Sináptica/genética , Transmissão Sináptica/fisiologia
5.
Nat Commun ; 11(1): 2123, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32358558

RESUMO

Mammals differ in their regeneration potential after traumatic injury, which might be caused by species-specific regeneration programs. Here, we compared murine and human Schwann cell (SC) response to injury and developed an ex vivo injury model employing surgery-derived human sural nerves. Transcriptomic and lipid metabolism analysis of murine SCs following injury of sural nerves revealed down-regulation of lipogenic genes and regulator of lipid metabolism, including Pparg (peroxisome proliferator-activated receptor gamma) and S1P (sphingosine-1-phosphate). Human SCs failed to induce similar adaptations following ex vivo nerve injury. Pharmacological PPARg and S1P stimulation in mice resulted in up-regulation of lipid gene expression, suggesting a role in SCs switching towards a myelinating state. Altogether, our results suggest that murine SC switching towards a repair state is accompanied by transcriptome and lipidome adaptations, which are reduced in humans.


Assuntos
Metabolismo dos Lipídeos/fisiologia , Células de Schwann/citologia , Células de Schwann/metabolismo , Animais , Feminino , Humanos , Lisofosfolipídeos/metabolismo , Masculino , Camundongos , Bainha de Mielina/metabolismo , Regeneração Nervosa/genética , Regeneração Nervosa/fisiologia , Sistema Nervoso/citologia , Sistema Nervoso/metabolismo , Neuroglia/citologia , Neuroglia/metabolismo , PPAR gama/metabolismo , Sistema Nervoso Periférico/citologia , Sistema Nervoso Periférico/metabolismo , Esfingosina/análogos & derivados , Esfingosina/metabolismo
6.
PLoS One ; 15(3): e0221006, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32187190

RESUMO

Homeodomain-interacting protein kinases (Hipks) have been previously associated with cell proliferation and cancer, however, their effects in the nervous system are less well understood. We have used Drosophila melanogaster to evaluate the effects of altered Hipk expression on the nervous system and muscle. Using genetic manipulation of Hipk expression we demonstrate that knockdown and over-expression of Hipk produces early adult lethality, possibly due to the effects on the nervous system and muscle involvement. We find that optimal levels of Hipk are critical for the function of dopaminergic neurons and glial cells in the nervous system, as well as muscle. Furthermore, manipulation of Hipk affects the structure of the larval neuromuscular junction (NMJ) by promoting its growth. Hipk regulates the phosphorylation of the synapse-associated cytoskeletal protein Hu-li tai shao (Hts; adducin in mammals) and modulates the expression of two important protein kinases, Calcium-calmodulin protein kinase II (CaMKII) and Partitioning-defective 1 (PAR-1), all of which may alter neuromuscular structure/function and influence lethality. Hipk also modifies the levels of an important nuclear protein, TBPH, the fly orthologue of TAR DNA-binding protein 43 (TDP-43), which may have relevance for understanding motor neuron diseases.


Assuntos
Proteínas de Drosophila/isolamento & purificação , Drosophila melanogaster/enzimologia , Drosophila melanogaster/fisiologia , Músculos/anatomia & histologia , Músculos/metabolismo , Sistema Nervoso/anatomia & histologia , Sistema Nervoso/metabolismo , Proteínas Quinases/isolamento & purificação , Animais , Padronização Corporal , Núcleo Celular/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/anatomia & histologia , Olho/embriologia , Larva/metabolismo , Masculino , Músculos/citologia , Sistema Nervoso/citologia , Junção Neuromuscular/metabolismo , Tamanho do Órgão , Fosforilação , Sinapses/metabolismo
7.
Eur Biophys J ; 48(7): 593-598, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31280337

RESUMO

Cell membrane nanotubes, variously referred to as tunneling nanotubes and cytonemes, are currently the focus of much interest. They are of ancient origin, as indicated by their opportunistic use for cell invasion by pathogens, including bacteria and virus, and by their employment in bacterial networking. They play a significant role in cancer invasion and in the explanation of glioblastoma resistance to treatment. Their structure and properties have been investigated with optical tweezers. They have been detected in vivo. Their role in the immune system was early verified. Very recently, it was shown that they share many properties with nerve synapses, including the roles of glutamate and Ca ions. Similar features have also been observed in primitive plants. These results support the conjecture that, besides their roles in immunology, developmental biology and cancer, cell membrane nanotubes are the ancestors of the nervous system.


Assuntos
Membrana Celular , Nanoestruturas , Sistema Nervoso/citologia , Membrana Celular/metabolismo , Membrana Celular/patologia , Doença , Humanos , Neurônios/citologia , Neurônios/patologia
8.
Dev Neurobiol ; 79(5): 497-517, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31102334

RESUMO

Mathematical and computational modeling enables biologists to integrate data from observations and experiments into a theoretical framework. In this review, we describe how developmental processes associated with stem-cell-driven growth of tissue in both the embryonic and adult nervous system can be modeled using cellular automata (CA). A cellular automaton is defined by its discrete nature in time, space, and state. The discrete space is represented by a uniform grid or lattice containing agents that interact with other agents within their local neighborhood. This possibility of local interactions of agents makes the cellular automata approach particularly well suited for studying through modeling how complex patterns at the tissue level emerge from fundamental developmental processes (such as proliferation, migration, differentiation, and death) at the single-cell level. As part of this review, we provide a primer for how to define biologically inspired rules governing these processes so that they can be implemented into a CA model. We then demonstrate the power of the CA approach by presenting simulations (in the form of figures and movies) based on building models of three developmental systems: the formation of the enteric nervous system through invasion by neural crest cells; the growth of normal and tumorous neurospheres induced by proliferation of adult neural stem/progenitor cells; and the neural fate specification through lateral inhibition of embryonic stem cells in the neurogenic region of Drosophila.


Assuntos
Modelos Neurológicos , Sistema Nervoso/crescimento & desenvolvimento , Células-Tronco Neurais , Animais , Fenômenos Fisiológicos Celulares , Simulação por Computador , Drosophila , Sistema Nervoso/citologia , Células-Tronco Neurais/citologia , Células-Tronco Neurais/fisiologia , Neurogênese/fisiologia
9.
Elife ; 82019 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-30694177

RESUMO

Dendritic arbors are crucial for nervous system assembly, but the intracellular mechanisms that govern their assembly remain incompletely understood. Here, we show that the dendrites of PVD neurons in Caenorhabditis elegans are patterned by distinct pathways downstream of the DMA-1 leucine-rich transmembrane (LRR-TM) receptor. DMA-1/LRR-TM interacts through a PDZ ligand motif with the guanine nucleotide exchange factor TIAM-1/GEF in a complex with act-4/Actin to pattern higher order 4° dendrite branches by localizing F-actin to the distal ends of developing dendrites. Surprisingly, TIAM-1/GEF appears to function independently of Rac1 guanine nucleotide exchange factor activity. A partially redundant pathway, dependent on HPO-30/Claudin, regulates formation of 2° and 3° branches, possibly by regulating membrane localization and trafficking of DMA-1/LRR-TM. Collectively, our experiments suggest that HPO-30/Claudin localizes the DMA-1/LRR-TM receptor on PVD dendrites, which in turn can control dendrite patterning by directly modulating F-actin dynamics through TIAM-1/GEF.


Assuntos
Actinas/genética , Proteínas de Caenorhabditis elegans/genética , Caenorhabditis elegans/genética , Proteínas de Membrana/genética , Plasticidade Neuronal/genética , Proteína 1 Indutora de Invasão e Metástase de Linfoma de Células T/genética , Actinas/metabolismo , Animais , Caenorhabditis elegans/citologia , Caenorhabditis elegans/crescimento & desenvolvimento , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Claudinas/genética , Claudinas/metabolismo , Regulação da Expressão Gênica , Proteínas de Membrana/metabolismo , Sistema Nervoso/citologia , Sistema Nervoso/crescimento & desenvolvimento , Sistema Nervoso/metabolismo , Neurogênese/genética , Neurônios/citologia , Neurônios/metabolismo , Domínios PDZ , Ligação Proteica , Transporte Proteico , Transmissão Sináptica , Proteína 1 Indutora de Invasão e Metástase de Linfoma de Células T/metabolismo , Proteínas rac1 de Ligação ao GTP/genética , Proteínas rac1 de Ligação ao GTP/metabolismo
10.
Int J Mol Sci ; 19(12)2018 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-30513991

RESUMO

Recent studies have clarified many still unknown aspects related to innate immunity and the blood-brain barrier relationship. They have also confirmed the close links between effector immune system cells, such as granulocytes, macrophages, microglia, natural killer cells and mast cells, and barrier functionality. The latter, in turn, is able to influence not only the entry of the cells of the immune system into the nervous tissue, but also their own activation. Interestingly, these two components and their interactions play a role of great importance not only in infectious diseases, but in almost all the pathologies of the central nervous system. In this paper, we review the main aspects in the field of vascular diseases (cerebral ischemia), of primitive and secondary neoplasms of Central Nervous System CNS, of CNS infectious diseases, of most common neurodegenerative diseases, in epilepsy and in demyelinating diseases (multiple sclerosis). Neuroinflammation phenomena are constantly present in all diseases; in every different pathological state, a variety of innate immunity cells responds to specific stimuli, differentiating their action, which can influence the blood-brain barrier permeability. This, in turn, undergoes anatomical and functional modifications, allowing the stabilization or the progression of the pathological processes.


Assuntos
Imunidade Inata , Sistema Nervoso/irrigação sanguínea , Sistema Nervoso/citologia , Animais , Barreira Hematoencefálica/patologia , Humanos , Sistema Nervoso/imunologia
11.
Development ; 145(14)2018 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-29945870

RESUMO

The zebrafish posterior lateral line primordium migrates along a path defined by the chemokine Cxcl12a, periodically depositing neuromasts, to pioneer formation of the zebrafish posterior lateral line system. snail1b, known for its role in promoting cell migration, is expressed in leading cells of the primordium in response to Cxcl12a, whereas its expression in trailing cells is inhibited by Fgf signaling. snail1b knockdown delays initiation of primordium migration. This delay is associated with aberrant expansion of epithelial cell adhesion molecule (epcam) and reduction of cadherin 2 expression in the leading part of the primordium. Co-injection of snail1b morpholino with snail1b mRNA prevents the initial delay in migration and restores normal expression of epcam and cadherin 2 The delay in initiating primordium migration in snail1b morphants is accompanied by a delay in sequential formation of trailing Fgf signaling centers and associated protoneuromasts. This delay is not specifically associated with knockdown of snail1b but also with other manipulations that delay migration of the primordium. These observations reveal an unexpected link between the initiation of collective migration and sequential formation of protoneuromasts in the primordium.


Assuntos
Movimento Celular/genética , Quimiocina CXCL2/metabolismo , Fatores de Crescimento de Fibroblastos/metabolismo , Sistema da Linha Lateral/embriologia , Sistema Nervoso/embriologia , Fatores de Transcrição da Família Snail/genética , Proteínas de Peixe-Zebra/genética , Peixe-Zebra/embriologia , Animais , Movimento Celular/efeitos dos fármacos , Quimiocina CXCL12 , Quimiocinas/metabolismo , Embrião não Mamífero/citologia , Embrião não Mamífero/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Sistema da Linha Lateral/citologia , Sistema da Linha Lateral/efeitos dos fármacos , Sistema da Linha Lateral/metabolismo , Modelos Biológicos , Morfolinos/farmacologia , Sistema Nervoso/citologia , Fatores de Transcrição da Família Snail/metabolismo , Células-Tronco/citologia , Células-Tronco/efeitos dos fármacos , Células-Tronco/metabolismo , Imagem com Lapso de Tempo , Via de Sinalização Wnt/efeitos dos fármacos , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
12.
Food Chem Toxicol ; 118: 13-23, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29709612

RESUMO

Iron oxide nanoparticles (ION) have great potential for an increasing number of medical and biological applications, particularly those focused on nervous system. Although ION seem to be biocompatible and present low toxicity, it is imperative to unveil the potential risk for the nervous system associated to their exposure, especially because current data on ION effects on human nervous cells are scarce. Thus, in the present study potential toxicity associated with silica-coated ION (S-ION) exposure was evaluated on human A172 glioblastoma cells. To this aim, a complete toxicological screening testing several exposure times (3 and 24 h), nanoparticle concentrations (5-100 µg/ml), and culture media (complete and serum-free) was performed to firstly assess S-ION effects at different levels, including cytotoxicity - lactate dehydrogenase assay, analysis of cell cycle and cell death production - and genotoxicity - H2AX phosphorylation assessment, comet assay, micronucleus test and DNA repair competence assay. Results obtained showed that S-ION exhibit certain cytotoxicity, especially in serum-free medium, related to cell cycle disruption and cell death induction. However, scarce genotoxic effects and no alteration of the DNA repair process were observed. Results obtained in this work contribute to increase the knowledge on the impact of ION on the human nervous system cells.


Assuntos
Astrócitos/efeitos dos fármacos , Materiais Revestidos Biocompatíveis , Compostos Férricos/toxicidade , Nanopartículas Metálicas/toxicidade , Dióxido de Silício/química , Testes de Carcinogenicidade , Ciclo Celular/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Meios de Cultura , Reparo do DNA , Histonas/metabolismo , Humanos , Nanopartículas Metálicas/química , Microscopia Eletrônica de Transmissão , Testes de Mutagenicidade , Sistema Nervoso/citologia , Sistema Nervoso/efeitos dos fármacos , Fosforilação
13.
Nutr Res ; 52: 80-86, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29526395

RESUMO

Saturated fatty acids (SFAs) induce reactive oxygen species (ROS) production in neurons. Extracellular signal regulated kinase (ERK)/nuclear factor erythroid-2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) is a ROS response pathway. Therefore, high ROS is always accompanied by increase of HO-1, an anti-oxidative enzyme; but it remains unknown why there is no significant reduction of ROS with the increase of HO-1 in SFAs-treated neurons. We hypothesized that the up-regulation of HO-1 is compensatory for response to fatty acid-induced oxidative stress but not enough to reduce ROS levels. We evaluated the anti-ROS effect of HO-1 and the involved pathway in palmitic acid (PA)-treated human neuroblastoma BE(2)-M17 cells. As expected, PA-induced ROS increase was accompanied by activation of the ERK-Nrf2-HO-1 pathway, as demonstrated by an increase in ERK phosphorylation, Nrf2 phosphorylation and nuclear accumulation, and HO-1 expression at the mRNA and protein levels, in a PA-dose-dependent manner. In contrast, administration of the ROS scavenger NAC significantly reduced the levels of PA-regulated ROS and HO-1 protein. However, the ERK inhibitor U0126 not only reversed the activating effect of PA on the ERK-Nrf2-HO-1 pathway but also aggravated PA-induced ROS. Furthermore, the Nrf2-specific activator NK-252 significantly increased PA-up-regulated HO-1 protein and alleviated PA-induced ROS. Therefore, our results suggest that up-regulation of HO-1 in PA-treated neurons is a compensatory response to ROS increase and that increasing HO-1 expression by Nrf2 activation can prevent the process of ROS production in PA-treated neurons.


Assuntos
Heme Oxigenase-1/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Sistema Nervoso/efeitos dos fármacos , Estresse Oxidativo , Ácido Palmítico/efeitos adversos , Espécies Reativas de Oxigênio/metabolismo , Regulação para Cima , Adaptação Fisiológica , Doença de Alzheimer/metabolismo , Antioxidantes/farmacologia , Linhagem Celular , Gorduras na Dieta/efeitos adversos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Humanos , Sistema Nervoso/citologia , Sistema Nervoso/metabolismo , Neuroblastoma , Fosforilação , RNA Mensageiro/metabolismo , Transdução de Sinais
14.
Cell Death Differ ; 24(8): 1411-1421, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28644437

RESUMO

Nervous systems are arguably the most fascinating and complex structures in the known universe. How they are built, changed by experience and then degenerate are some of the biggest questions in biology. Regressive phenomena, such as neuron pruning and programmed cell death, have a key role in the building and maintenance of the nervous systems. Both of these cellular mechanisms deploy the caspase family of protease enzymes. In this review, we highlight the non-apoptotic function of caspases during nervous system development, plasticity and disease, particularly focussing on their role in structural remodelling. We have classified pruning as either macropruning, where complete branches are removed, or micropruning, where individual synapses or dendritic spines are eliminated. Finally we discuss open questions and possible future directions within the field.


Assuntos
Caspases/genética , Sistema Nervoso/enzimologia , Doenças Neurodegenerativas/genética , Neurogênese/genética , Neurônios/enzimologia , Animais , Apoptose/genética , Caspases/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Sistema Nervoso/citologia , Sistema Nervoso/crescimento & desenvolvimento , Doenças Neurodegenerativas/metabolismo , Doenças Neurodegenerativas/patologia , Plasticidade Neuronal/genética , Neurônios/citologia , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Receptores de AMPA/genética , Receptores de AMPA/metabolismo , Receptores de N-Metil-D-Aspartato/genética , Receptores de N-Metil-D-Aspartato/metabolismo , Transdução de Sinais , Sinapses/genética
15.
Dev Genes Evol ; 227(1): 11-23, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27833997

RESUMO

The nervous system of the antenna of the grasshopper Schistocerca gregaria consists of two nerve tracts in which sensory cells project their axons to the brain. Each tract is pioneered early in embryogenesis by a pair of identified cells located apically in the antennal lumen. The pioneers are thought to originate in the epithelium of the antenna and then delaminate into the lumen where they commence axogenesis. However, unambiguous molecular identification of these cells in the epithelium, of an identifiable precursor, and of their mode of generation has been lacking. In this study, we have used immunolabeling against neuron-specific horseradish peroxidase and against Lachesin, a marker for differentiating epithelial cells, in combination with the nuclear stain DAPI, to identify the pioneers within the epithelium of the early embryonic antenna. We then track their delamination into the lumen as differentiated neurons. The pioneers are not labeled by the mesodermal/mesectodermal marker Mes3, consistent with an epithelial (ectodermal) origin. Intracellular dye injection, as well as labeling against the mitosis marker phospho-histone 3, identifies precursor cells in the epithelium, each associated with a column of cells. Culturing with the S-phase label 5-ethynyl-2'-deoxyuridine (EdU) shows that both a precursor and its column have incorporated the label, confirming a lineage relationship. Each set of pioneers can be shown to belong to a separate lineage of such epithelial cells, and the precursors remain and are proliferative after generating the pioneers. Analyses of mitotic spindle orientation then enable us to propose a model in which a precursor generates its pioneers asymmetrically via self-renewal.


Assuntos
Gafanhotos/crescimento & desenvolvimento , Animais , Antenas de Artrópodes/crescimento & desenvolvimento , Axônios/fisiologia , Células Epiteliais/citologia , Células Epiteliais/fisiologia , Gafanhotos/citologia , Gafanhotos/fisiologia , Mitose , Sistema Nervoso/citologia , Sistema Nervoso/crescimento & desenvolvimento , Neurônios/citologia , Fuso Acromático , Células-Tronco/citologia , Células-Tronco/fisiologia
16.
J Biomed Semantics ; 7(1): 44, 2016 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-27377652

RESUMO

BACKGROUND: The Cell Ontology (CL) is an OBO Foundry candidate ontology covering the domain of canonical, natural biological cell types. Since its inception in 2005, the CL has undergone multiple rounds of revision and expansion, most notably in its representation of hematopoietic cells. For in vivo cells, the CL focuses on vertebrates but provides general classes that can be used for other metazoans, which can be subtyped in species-specific ontologies. CONSTRUCTION AND CONTENT: Recent work on the CL has focused on extending the representation of various cell types, and developing new modules in the CL itself, and in related ontologies in coordination with the CL. For example, the Kidney and Urinary Pathway Ontology was used as a template to populate the CL with additional cell types. In addition, subtypes of the class 'cell in vitro' have received improved definitions and labels to provide for modularity with the representation of cells in the Cell Line Ontology and Reagent Ontology. Recent changes in the ontology development methodology for CL include a switch from OBO to OWL for the primary encoding of the ontology, and an increasing reliance on logical definitions for improved reasoning. UTILITY AND DISCUSSION: The CL is now mandated as a metadata standard for large functional genomics and transcriptomics projects, and is used extensively for annotation, querying, and analyses of cell type specific data in sequencing consortia such as FANTOM5 and ENCODE, as well as for the NIAID ImmPort database and the Cell Image Library. The CL is also a vital component used in the modular construction of other biomedical ontologies-for example, the Gene Ontology and the cross-species anatomy ontology, Uberon, use CL to support the consistent representation of cell types across different levels of anatomical granularity, such as tissues and organs. CONCLUSIONS: The ongoing improvements to the CL make it a valuable resource to both the OBO Foundry community and the wider scientific community, and we continue to experience increased interest in the CL both among developers and within the user community.


Assuntos
Ontologias Biológicas , Células , Processamento de Linguagem Natural , Sistema Nervoso/citologia
17.
Nat Rev Neurosci ; 17(3): 160-72, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26891626

RESUMO

Functional neural competence and integrity require interactive exchanges among sensory and motor neurons, interneurons and glial cells. Recent studies have attributed some of the tasks needed for these exchanges to extracellular vesicles (such as exosomes and microvesicles), which are most prominently involved in shuttling reciprocal signals between myelinating glia and neurons, thus promoting neuronal survival, the immune response mediated by microglia, and synapse assembly and plasticity. Such vesicles have also been identified as important factors in the spread of neurodegenerative disorders and brain cancer. These extracellular vesicle functions add a previously unrecognized level of complexity to transcellular interactions within the nervous system.


Assuntos
Comunicação Celular/fisiologia , Vesículas Extracelulares/fisiologia , Sistema Nervoso/citologia , Neurônios/fisiologia , Animais , Humanos , Neuroglia/fisiologia
18.
Acta Neuropathol Commun ; 3: 74, 2015 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-26610346

RESUMO

BACKGROUND: Tamoxifen (TAM) is an important cancer therapeutic and an experimental tool for effecting genetic recombination using the inducible Cre-Lox technique. Despite its widespread use in the clinic and laboratory, we know little about its effects on the nervous system. This is of significant concern because TAM, via unknown mechanisms, induces cognitive impairment in humans. A hallmark of cellular stress is induction of Activating Transcription Factor 3 (Atf3), and so to determine whether TAM induces cellular stress in the adult nervous system, we generated a knock-in mouse in which Atf3 promoter activity drives transcription of TAM-dependent Cre recombinase (Cre-ERT2); when crossed with tdtomato reporter mice, Atf3 induction results in robust and permanent genetic labeling of cells in which it is up-regulated even transiently. RESULTS: We found that granular neurons of the olfactory bulb and dentate gyrus, vascular cells and ependymal cells throughout the brain, and peripheral sensory neurons expressed tdtomato in response to TAM treatment. We also show that TAM induced Atf3 up-regulation through inhibition of cholesterol epoxide hydrolase (ChEH): reporter expression was mitigated by delivery in vitamin E-rich wheat germ oil (vitamin E depletes ChEH substrates), and was partially mimicked by a ChEH-specific inhibitor. CONCLUSIONS: This work demonstrates that TAM stresses cells of the adult central and peripheral nervous systems and highlights concerns about clinical and experimental use of TAM. We propose TAM administration in vitamin E-rich vehicles such as wheat germ oil as a simple remedy.


Assuntos
Colesterol/metabolismo , Sistema Nervoso/citologia , Neurônios/fisiologia , Moduladores Seletivos de Receptor Estrogênico/farmacologia , Tamoxifeno/farmacologia , Regulação para Cima/efeitos dos fármacos , Fator 3 Ativador da Transcrição/genética , Animais , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Relação Dose-Resposta a Droga , Epóxido Hidrolases/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mutação/genética , Proteínas do Tecido Nervoso/metabolismo , Neurônios/efeitos dos fármacos , Lectinas de Plantas/genética , Lectinas de Plantas/metabolismo , Óleos de Plantas/farmacologia , Regiões Promotoras Genéticas , Vitamina E/farmacologia
19.
Curr Top Dev Biol ; 114: 159-84, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26431567

RESUMO

Programmed cell death (PCD) is a fundamental component of nervous system development. PCD serves as the mechanism for quantitative matching of the number of projecting neurons and their target cells through direct competition for neurotrophic factors in the vertebrate peripheral nervous system. In addition, PCD plays roles in regulating neural cell numbers, canceling developmental errors or noise, and tissue remodeling processes. These findings are mainly derived from genetic studies that prevent cells from dying by apoptosis, which is a major form of PCD and is executed by activation of evolutionarily conserved cysteine protease caspases. Recent studies suggest that caspase activation can be coordinated in time and space at multiple levels, which might underlie nonapoptotic roles of caspases in neural development in addition to apoptotic roles.


Assuntos
Apoptose , Caspases/metabolismo , Sistema Nervoso/crescimento & desenvolvimento , Neurônios/citologia , Animais , Apoptose/fisiologia , Morte Celular , Diferenciação Celular , Linhagem da Célula , Sobrevivência Celular , Drosophila/crescimento & desenvolvimento , Ativação Enzimática , Olho/citologia , Olho/crescimento & desenvolvimento , Morfogênese , Sistema Nervoso/citologia , Neurogênese , Neuroglia/citologia
20.
Rev. Esc. Enferm. USP ; 48(spe): 53-58, 08/2014.
Artigo em Inglês | LILACS, BDENF | ID: lil-731286

RESUMO

Objective To understand the experiences and expectations of nurses in the treatment of women with chronic venous ulcers. Method Phenomenological research was based on Alfred Schütz, whose statements were obtained in January, 2012, through semi-structured interviews with seven nurses. Results The nurse reveals the difficulties presented by the woman in performing self-care, the perceived limitations in the treatment anchored in motivation, and the values and beliefs of women. It showed professional frustration because venous leg ulcer recurrence, lack of inputs, interdisciplinary work and training of nursing staff. There was an expected adherence to the treatment of women, and it emphasized the need for ongoing care, supported self-care and standard practices in treatment. Conclusion That treatment of chronic venous leg ulcers constitutes a challenge that requires collective investment, involving women, professionals, managers and health institutions. .


Objetivo Comprender las experiencias y expectativas de enfermeras en el tratamiento de mujeres con úlcera venosa crónica. Método Investigación fenomenológica fundamentada en Alfred Schutz, que buscó Se realizó entrevista semiestructurada con siete enfermeras, en enero del 2012. Resultados La enfermera revela dificultades presentadas por la mujer para realizar el autocuidado, percibe limitaciones en el tratamiento relacionadas con la desmotivación, los valores y las creencias de las mujeres. Refiere frustración profesional debido a la recidiva de la lesión, a la falta de insumos, al deficiente trabajo interdisciplinar y a la limitada capacitación del equipo de enfermeras. Espera la adhesión de la mujer al tratamiento y resalta la necesidad del cuidado continuo, del autocuidado apoyado y de estandarizar conductas de tratamiento. Conclusión El tratamiento de la úlcera venosa crónica es un desafío que requiere contribución colectiva, involucrando a las mujeres, a los profesionales, a los gestores y a las instituciones de salud. .


Objetivo Compreender as experiências e expectativas de enfermeiras no tratamento de mulheres com úlcera venosa crônica na Atenção Primária à Saúde. Método Pesquisa fundamentada na fenomenologia social de Alfred Schütz, com depoimentos obtidos em janeiro de 2012, por meio de entrevista semiestruturada com sete enfermeiras. Resultados As enfermeiras revelam dificuldades apresentadas pelas mulheres com úlcera venosa crônica para realizar o autocuidado, percebem limitações na terapêutica ancoradas na desmotivação e nos valores e crenças das mulheres. Referem frustração profissional em razão da recidiva da lesão, falta de insumos e tecnologia, de trabalho interdisciplinar e da capacitação da equipe de enfermagem. Esperam a adesão das mulheres ao tratamento e ressaltam a necessidade do cuidado contínuo, do autocuidado apoiado e da padronização de condutas no tratamento. Conclusão O tratamento da úlcera venosa crônica constitui-se em um desafio que requer investimento coletivo, envolvendo a mulher, os profissionais, os gestores e as instituições de saúde. .


Assuntos
Animais , Proteínas de Caenorhabditis elegans/isolamento & purificação , Caenorhabditis elegans/metabolismo , Membrana Celular/metabolismo , Canais Iônicos/isolamento & purificação , Canais Iônicos/metabolismo , Proteínas do Tecido Nervoso/isolamento & purificação , Proteínas do Tecido Nervoso/metabolismo , Sistema Nervoso/metabolismo , Neurônios Aferentes/metabolismo , Sensação/genética , Sequência de Aminoácidos/genética , Sequência de Bases/genética , Comportamento Animal/efeitos dos fármacos , Comportamento Animal/fisiologia , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/citologia , Capsaicina/farmacologia , Compartimento Celular/genética , Membrana Celular/efeitos dos fármacos , Membrana Celular/ultraestrutura , Regulação da Expressão Gênica/fisiologia , Canais Iônicos/genética , Canais Iônicos/ultraestrutura , Dados de Sequência Molecular , Mutação/genética , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/ultraestrutura , Sistema Nervoso/citologia , Sistema Nervoso/efeitos dos fármacos , Neurônios Aferentes/citologia , Neurônios Aferentes/efeitos dos fármacos , Dor/genética , Dor/metabolismo , Dor/fisiopatologia , Filogenia , Receptores de Droga/efeitos dos fármacos , Receptores de Droga/metabolismo , Receptores de Droga/ultraestrutura , Sensação/efeitos dos fármacos , Transdução de Sinais/genética , Canais de Cátion TRPV , Canais de Potencial de Receptor Transitório
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