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1.
Adv Exp Med Biol ; 1175: 93-115, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31583585

RESUMO

Astrocytes are secretory cells, actively participating in cell-to-cell communication in the central nervous system (CNS). They sense signaling molecules in the extracellular space, around the nearby synapses and also those released at much farther locations in the CNS, by their cell surface receptors, get excited to then release their own signaling molecules. This contributes to the brain information processing, based on diffusion within the extracellular space around the synapses and on convection when locales relatively far away from the release sites are involved. These functions resemble secretion from endocrine cells, therefore astrocytes were termed to be a part of the gliocrine system in 2015. An important mechanism, by which astrocytes release signaling molecules is the merger of the vesicle membrane with the plasmalemma, i.e., exocytosis. Signaling molecules stored in astroglial secretory vesicles can be discharged into the extracellular space after the vesicle membrane fuses with the plasma membrane. This leads to a fusion pore formation, a channel that must widen to allow the exit of the Vesiclal cargo. Upon complete vesicle membrane fusion, this process also integrates other proteins, such as receptors, transporters and channels into the plasma membrane, determining astroglial surface signaling landscape. Vesiclal cargo, together with the whole vesicle can also exit astrocytes by the fusion of multivesicular bodies with the plasma membrane (exosomes) or by budding of vesicles (ectosomes) from the plasma membrane into the extracellular space. These astroglia-derived extracellular vesicles can later interact with various target cells. Here, the characteristics of four types of astroglial secretory vesicles: synaptic-like microvesicles, dense-core vesicles, secretory lysosomes, and extracellular vesicles, are discussed. Then machinery for vesicle-based exocytosis, second messenger regulation and the kinetics of exocytotic vesicle content discharge or release of extracellular vesicles are considered. In comparison to rapidly responsive, electrically excitable neurons, the receptor-mediated cytosolic excitability-mediated astroglial exocytotic vesicle-based transmitter release is a relatively slow process.


Assuntos
Astrócitos/citologia , Sistema Nervoso Central/citologia , Exocitose , Vesículas Secretórias/fisiologia , Humanos , Fusão de Membrana
2.
Adv Exp Med Biol ; 1175: 227-272, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31583591

RESUMO

Motor neuron disorders are highly debilitating and mostly fatal conditions for which only limited therapeutic options are available. To overcome this limitation and develop more effective therapeutic strategies, it is critical to discover the pathogenic mechanisms that trigger and sustain motor neuron degeneration with the greatest accuracy and detail. In the case of Amyotrophic Lateral Sclerosis (ALS), several genes have been associated with familial forms of the disease, whilst the vast majority of cases develop sporadically and no defined cause can be held responsible. On the contrary, the huge majority of Spinal Muscular Atrophy (SMA) occurrences are caused by loss-of-function mutations in a single gene, SMN1. Although the typical hallmark of both diseases is the loss of motor neurons, there is increasing awareness that pathological lesions are also present in the neighbouring glia, whose dysfunction clearly contributes to generating a toxic environment in the central nervous system. Here, ALS and SMA are sequentially presented, each disease section having a brief introduction, followed by a focussed discussion on the role of the astrocytes in the disease pathogenesis. Such a dissertation is substantiated by the findings that built awareness on the glial involvement and how the glial-neuronal interplay is perturbed, along with the appraisal of this new cellular site for possible therapeutic intervention.


Assuntos
Esclerose Amiotrófica Lateral/fisiopatologia , Astrócitos/citologia , Neurônios Motores/patologia , Atrofia Muscular Espinal/fisiopatologia , Humanos , Mutação
3.
Adv Exp Med Biol ; 1175: 273-324, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31583592

RESUMO

Alzheimer's disease is the most common cause of dementia. Cellular changes in the brains of the patients suffering from Alzheimer's disease occur well in advance of the clinical symptoms. At the cellular level, the most dramatic is a demise of neurones. As astroglial cells carry out homeostatic functions of the brain, it is certain that these cells are at least in part a cause of Alzheimer's disease. Historically, Alois Alzheimer himself has recognised this at the dawn of the disease description. However, the role of astroglia in this disease has been understudied. In this chapter, we summarise the various aspects of glial contribution to this disease and outline the potential of using these cells in prevention (exercise and environmental enrichment) and intervention of this devastating disease.


Assuntos
Doença de Alzheimer/fisiopatologia , Astrócitos/citologia , Neuroglia/citologia , Encéfalo/fisiopatologia , Humanos
4.
Adv Exp Med Biol ; 1175: 355-381, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31583595

RESUMO

Huntington's disease (HD) is a dominantly inherited neurodegenerative disease that results in motor, cognitive and psychiatric dysfunction. It is caused by a polyglutamine repeat expansion mutation in the widely expressed HTT protein. The clinical manifestations of HD have been largely attributed to the neurodegeneration of specific neuronal cell types in the brain. However, it has become clear that other cell types, including astrocytes, play important roles in the pathogenesis of HD. The mutant HTT (mHTT) protein is present in neuronal and non-neuronal cell types throughout the nervous system. Studies designed to understand the contribution of mHTT expression in non-neuronal cell types to HD pathogenesis has lagged considerably behind those focused on neurons. However, the role of astrocytes in HD has received more attention over the last 5-10 years. In this chapter we present an overview of HD and our current understanding of astrocytic involvement in this disease. We describe the neuropathological features of HD and provide evidence of morphological and molecular changes in mHTT expressing astrocytes. We review data from animal models and HD patients that implicate mHTT expressing astrocytes to the progression of HD.


Assuntos
Astrócitos/citologia , Doença de Huntington/fisiopatologia , Animais , Modelos Animais de Doenças , Humanos , Neurônios
5.
Adv Exp Med Biol ; 1175: 383-405, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31583596

RESUMO

Despite over a century of research into Alzheimer's disease (AD), progress in understanding the complex aetiology has been hindered, in part, by a lack of human, disease relevant, cellular models, reflected in an inability to translate results from animal studies to successful human therapies. Induced pluripotent stem cell (iPSC) technology, in which somatic cells are reprogrammed to pluripotent stem cells, creates an ideal physiologically relevant model as they maintain the genetic identity of the donor. These iPSCs can self-renew indefinitely in vitro and have the capacity to differentiate into any cell type, opening up new discovery and therapeutic opportunities. Despite a plethora of publications indicating the generation and utility of iPSC-derived neurones for disease modelling to date, in comparison only a limited number of studies have described generation of enriched astroglia from patients with early- or late-stage onset of AD. We recently reported that iPSC-astroglia derived from these patients are capable of mimicking a wide variety of deficits in homeostatic molecular cascades, intimately associated with AD, that are routinely observed in vivo. This review examines the opportunities and limitations of this innovative technology in the context of AD modelling and uses for preclinical discovery to improve our success for an efficacious therapeutic outcome.


Assuntos
Doença de Alzheimer , Astrócitos/citologia , Células-Tronco Pluripotentes Induzidas/citologia , Animais , Humanos , Neurônios
6.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 41(4): 524-528, 2019 Aug 30.
Artigo em Chinês | MEDLINE | ID: mdl-31484616

RESUMO

To compare the biological functions of astrocytes cultured in vitro by two methods. Methods The primary astrocytes were cultured from rodent neonatal brain,whereas the differentiated astrocytes were prepared by differentiating neural stem cells with fetal bovine serum.The morphologies of these two different types of astrocytes were observed under microscope and the expression of glial fibrillary acidic protein(GFAP),an astrocyte-specific marker,was detected by immunofluorescence staining after treatment with 10 cytokines.Changes in GFAP,glutamate synthetase(GS),glutamate-aspartic acid transporter(xCT),neuregulin-1(NRG),N-methyl-D-aspartic acid receptor(NMDA),lipoprotein lipase(LPL)were detected and compared. Results The morphologies and GFAP expression differed between these two astrocyte types.Microarray showed that the expressions of GFAP,GS,xCT,NRG,NMDA,and LPL were significantly higher in primary astrocytes than in differentiated astrocytes.None of these 10 cytokines increased the expression of GFAP in primary astrocytes,whereas treatment with transforming growth factor-ß(TGF-ß)significantly increased the expression of GFAP in the differentiated astrocytes. Conclusion Compared with the differentiated astrocytes,the primary astrocytes are more similar to reactive astrocytes,and TGF-ß can promote the transition of differentiated cells to reactive cells.


Assuntos
Astrócitos/citologia , Diferenciação Celular , Animais , Animais Recém-Nascidos , Células Cultivadas , Proteína Glial Fibrilar Ácida/metabolismo , Células-Tronco Neurais/citologia , Roedores , Fator de Crescimento Transformador beta/farmacologia
7.
Adv Exp Med Biol ; 1169: 31-53, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31487017

RESUMO

The discovery of neural stem cells in the adult mammalian hippocampus has attracted attention and controversy, which both continue to this day. Hippocampal neural stem cells and their immediate progeny, amplifying neuroprogenitor cells, give rise to neurons and astrocytes in the region. Envisioned as possible key for tissue regeneration, whether mobilized endogenously or transplanted exogenously, neural stem cells have been in the eye of both public and science over the course of the past 20 years. These cells are a heterogeneous population, and here, we review different aspects of their heterogeneity from morphology to metabolism and response to different stimuli.


Assuntos
Hipocampo , Células-Tronco Neurais , Animais , Astrócitos/citologia , Diferenciação Celular , Hipocampo/citologia , Humanos , Células-Tronco Neurais/citologia , Neurogênese , Neurônios/citologia
8.
Chem Biol Interact ; 309: 108686, 2019 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-31152735

RESUMO

Acetylcholinesterase (EC3.1.1.7; AChE) is a key enzyme in the cholinergic system. Emerging evidence has shown that 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), a typical persistent organic pollutant, suppressed neuronal AChE activity via dysregulation of different biosynthesis processes in human and rat neuronal cells. In the nervous system, astrocytes protect neurons from environmental pollutants. As a known target cell of TCDD, the astrocyte might be involved in TCDD effects on neuronal AChE. Therefore, in the present study, we found astrocyte-derived conditioned medium (ACM) could induce AChE activity preferentially in mature neurons in the absence of TCDD. The enzymatic activity of AChE was generally decreased in cultured cortical neurons upon direct treatment with TCDD (0.003-0.01 nM). This trend of changes in AChE activity was not significantly altered in immature neurons exposed to ACM produced in the presence of TCDD (TACM group), but reversed in mature neurons. Compared with effects of treatment with ACM plus TCDD (ACMT), a significant differential effect on AChE activity was found in the TACM group in response to TCDD treatment specifically in immature neurons, suggesting the presence of a TCDD-specific active component derived from the astrocyte. Inconsistent alterations in expression and enzymatic activities of the AChE T subunit (AChET) and the proline-rich membrane anchor (PRiMA) were found, suggesting that a mechanism of action beyond the transcriptional level might be involved. These data indicate that the astrocyte might play a protective role in TCDD-induced alterations of neuronal AChE in certain stages of differentiation.


Assuntos
Acetilcolinesterase/metabolismo , Meios de Cultivo Condicionados/química , Expressão Gênica/efeitos dos fármacos , Dibenzodioxinas Policloradas/farmacologia , Acetilcolinesterase/genética , Animais , Astrócitos/citologia , Astrócitos/metabolismo , Células Cultivadas , Meios de Cultivo Condicionados/farmacologia , Neurônios/citologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Dibenzodioxinas Policloradas/química , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley
9.
Nat Commun ; 10(1): 2541, 2019 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-31186414

RESUMO

Reactive astrocytes evolve after brain injury, inflammatory and degenerative diseases, whereby they undergo transcriptomic re-programming. In malignant brain tumors, their function and crosstalk to other components of the environment is poorly understood. Here we report a distinct transcriptional phenotype of reactive astrocytes from glioblastoma linked to JAK/STAT pathway activation. Subsequently, we investigate the origin of astrocytic transformation by a microglia loss-of-function model in a human organotypic slice model with injected tumor cells. RNA-seq based gene expression analysis of astrocytes reveals a distinct astrocytic phenotype caused by the coexistence of microglia and astrocytes in the tumor environment, which leads to a large release of anti-inflammatory cytokines such as TGFß, IL10 and G-CSF. Inhibition of the JAK/STAT pathway shifts the balance of pro- and anti-inflammatory cytokines towards a pro-inflammatory environment. The complex interaction of astrocytes and microglia cells promotes an immunosuppressive environment, suggesting that tumor-associated astrocytes contribute to anti-inflammatory responses.


Assuntos
Astrócitos/metabolismo , Citocinas/metabolismo , Glioblastoma/imunologia , Microglia/metabolismo , Astrócitos/citologia , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Perfilação da Expressão Gênica , Humanos , Mediadores da Inflamação , Janus Quinases/metabolismo , Microglia/citologia , Fenótipo , Fatores de Transcrição STAT/metabolismo , Análise de Sequência de RNA , Transdução de Sinais , Técnicas de Cultura de Tecidos
10.
Mol Cells ; 42(4): 321-332, 2019 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-31085806

RESUMO

The brain is the most common metastatic site of lung adenocarcinoma; however, the mechanism of this selective metastasis remains unclear. We aimed to verify the hypothesis that exposure of tumor cells to the brain microenvironment leads to changes in their gene expression, which promotes their oriented transfer to the brain. A549 and H1299 lung adenocarcinoma cells were exposed to human astrocyte-conditioned medium to simulate the brain microenvironment. Microarray analysis was used to identify differentially expressed genes, which were confirmed by quantitative real-time PCR and western blotting. Knockdown experiments using microRNAs and the overexpression of genes by cell transfection were performed in addition to migration and invasion assays. In vitro findings were confirmed in clinical specimens using immunohistochemistry. We found and confirmed a significant increase in insulin-like growth factor binding protein-3 (IGFBP3) levels. Our results also showed that the up-regulation of IGFBP3 promoted A549 cell epithelial-mesenchymal transition, migration, and invasion, while the knockdown of IGFBP3 resulted in decreased cell motility. We also found that Transforming growth factor-ß (TGF-ß)/Mothers against decapentaplegic homolog 4 (Smad4)-induced epithelial-mesenchymal transition was likely IGFBP3-dependent in A549 cells. Finally, expression of IGFBP3 was significantly elevated in pulmonary cancer tissues and intracranial metastatic tissues. Our data indicate that up-regulation of IGFBP3 might mediate brain metastasis in lung adenocarcinoma, which makes it a potential therapeutic target.


Assuntos
Adenocarcinoma de Pulmão/metabolismo , Astrócitos/citologia , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/secundário , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/genética , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Neoplasias Pulmonares/metabolismo , Regulação para Cima , Células A549 , Adenocarcinoma de Pulmão/genética , Astrócitos/metabolismo , Neoplasias Encefálicas/genética , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Meios de Cultivo Condicionados/farmacologia , Transição Epitelial-Mesenquimal , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Análise de Sequência com Séries de Oligonucleotídeos
11.
Artif Cells Nanomed Biotechnol ; 47(1): 1917-1923, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31079497

RESUMO

OBJECTIVE: To investigate the effect of Sulfiredoxin-1 (Srxn1) on astrocyte injury induced by hydrogen peroxide (H2O2). METHODS: Observing the changes of H2O2 on contents of lactate dehydrogenase (LDH), malondialdehyde (MDA), superoxide dismutase (SOD) and apoptosis after transfected Srxn1 siRNA into astrocytes. The protein expression of Notch 1, NICD and Hes1, the content of LDH and MDA, the activity of SOD and apoptosis rate of astrocytes after inhibiting or activation of Notch signalling pathway were detected by Western blot, ELISA and flow cytometry, respectively. RESULTS: Knockdown of Srxn1 could promote the secretion of LDH and MDA, decrease the activity of SOD and aggravate apoptosis of astrocytes induced by H2O2. The results of Western blot, ELISA assay and flow cytometry indicated that activation of the Notch signalling pathway attenuated the effect of Srxn1 on H2O2-induced oxidative damage and apoptosis of astrocytes. CONCLUSION: Srxn1 may protect astrocytes from oxidative stress injury induced by H2O2 by activation of Notch signalling pathway.


Assuntos
Astrócitos/citologia , Astrócitos/efeitos dos fármacos , Peróxido de Hidrogênio/farmacologia , Oxirredutases atuantes sobre Doadores de Grupo Enxofre/metabolismo , Receptores Notch/metabolismo , Transdução de Sinais/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Apoptose/efeitos dos fármacos , Astrócitos/metabolismo , Proliferação de Células/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Técnicas de Silenciamento de Genes , L-Lactato Desidrogenase/metabolismo , Malondialdeído/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Oxirredutases atuantes sobre Doadores de Grupo Enxofre/deficiência , Oxirredutases atuantes sobre Doadores de Grupo Enxofre/genética , Ratos , Ratos Sprague-Dawley , Superóxido Dismutase/metabolismo
12.
Cell Biol Int ; 43(7): 809-819, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31050073

RESUMO

Our research group has developed a cell-penetrating peptide-based delivery system that includes the Asn194Lys mutation in the rabies virus glycoprotein-9R peptide (mRVG-9R). This system has the capacity to deliver DNA in astrocytes and SH-SY5Y cells. The aim of this study was to evaluate the ability of the mRVG-9R peptide to deliver DNA molecules to murine brain cells. The mRVG-9R peptide, a karyophilic peptide (KP) and a plasmid encoding green fluorescent protein (GFP) were bound by electrostatic charges to form the mRVG-9R complex. mRVG-9R complex was injected into the cerebral cortex, striatum and hippocampus of C57BL/6 mice by stereotactic surgery. After 2, 4, and 20 days, the animals were sacrificed and their brains were prepared for quantitative reverse-transcription polymerase chain reaction and histological analysis. We detected the GFP expression in neurons and glial cells in the cerebral cortex, striatum, and hippocampus of the murine brain. The results suggest that the mRVG-9R peptide has the ability to deliver DNA molecules to murine brain cells. Also, the expression of the reporter gene is maintained at least up to 20 days after injection in neurons, astrocytes, oligodendrocytes, and microglia cells. Thus, the in vivo transfection ability of the mRVG-9R peptide, makes it a promising candidate as a therapeutic gene delivery vector to the central nervous system cells.


Assuntos
Peptídeos Penetradores de Células/farmacologia , Corpo Estriado/efeitos dos fármacos , Portadores de Fármacos/farmacologia , Glicoproteínas/farmacologia , Proteínas de Fluorescência Verde/metabolismo , Hipocampo/efeitos dos fármacos , Fragmentos de Peptídeos/farmacologia , Proteínas Virais/farmacologia , Animais , Astrócitos/citologia , Astrócitos/efeitos dos fármacos , Corpo Estriado/citologia , Genes Reporter , Vetores Genéticos/uso terapêutico , Proteínas de Fluorescência Verde/genética , Hipocampo/citologia , Camundongos , Camundongos Endogâmicos C57BL , Microglia/citologia , Neurônios/citologia , Neurônios/efeitos dos fármacos , Oligodendroglia/citologia , Oligodendroglia/efeitos dos fármacos , Transfecção/métodos
13.
BMC Res Notes ; 12(1): 225, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30987672

RESUMO

OBJECTIVE: Delivery of constructs for silencing or over-expressing genes or their modified versions is a crucial step for studying neuronal cell biology. Therefore, efficient transfection is important for the success of these experimental techniques especially in post-mitotic cells like neurons. In this study, we have assessed the transfection rate, using a previously established protocol, in both primary cortical cultures and neuroblastoma cell lines. Transfection efficiencies in these preparations have not been systematically determined before. RESULTS: Transfection efficiencies obtained herein were (10-12%) for neuroblastoma, (5-12%) for primary astrocytes and (1.3-6%) for primary neurons. We also report on cell-type specific transfection efficiency of neurons and astrocytes within primary cortical cultures when applying cell-type selective transfection protocols. Previous estimations described in primary cortical or hippocampal cultures were either based on general observations or on data derived from unspecified number of biological and/or technical replicates. Also to the best of our knowledge, transfection efficiency of pure primary neuronal cultures or astrocytes cultured in the context of pure or mixed (neurons/astrocytes) population cultures have not been previously determined. The transfection strategy used herein represents a convenient, and a straightforward tool for targeted cell transfection that can be utilized in a variety of in vitro applications.


Assuntos
Astrócitos/metabolismo , Células-Tronco Neurais/metabolismo , Neurônios/metabolismo , Plasmídeos/metabolismo , Transfecção/métodos , Animais , Antígenos Nucleares/genética , Antígenos Nucleares/metabolismo , Astrócitos/citologia , Astrócitos/efeitos dos fármacos , Biomarcadores/metabolismo , Diferenciação Celular , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Córtex Cerebral/citologia , Córtex Cerebral/metabolismo , Técnicas de Cocultura , Expressão Gênica , Genes Reporter , Proteína Glial Fibrilar Ácida/genética , Proteína Glial Fibrilar Ácida/metabolismo , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Humanos , Lipídeos/química , Lipídeos/farmacologia , Camundongos , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Células-Tronco Neurais/citologia , Células-Tronco Neurais/efeitos dos fármacos , Neurônios/citologia , Neurônios/efeitos dos fármacos , Especificidade de Órgãos , Plasmídeos/química , Cultura Primária de Células
15.
Int J Mol Sci ; 20(8)2019 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-31013990

RESUMO

Methyl CpG binding protein-2 (MeCP2) isoforms (E1 and E2) are important epigenetic regulators in brain cells. Accordingly, MeCP2 loss- or gain-of-function mutation causes neurodevelopmental disorders, including Rett syndrome (RTT), MECP2 duplication syndrome (MDS), and autism spectrum disorders (ASD). Within different types of brain cells, highest MeCP2 levels are detected in neurons and the lowest in astrocytes. However, our current knowledge of Mecp2/MeCP2 regulatory mechanisms remains largely elusive. It appears that there is a sex-dependent effect in X-linked MeCP2-associated disorders, as RTT primarily affects females, whereas MDS is found almost exclusively in males. This suggests that Mecp2 expression levels in brain cells might be sex-dependent. Here, we investigated the sex- and cell type-specific expression of Mecp2 isoforms in male and female primary neurons and astrocytes isolated from the murine forebrain. Previously, we reported that DNA methylation of six Mecp2 regulatory elements correlated with Mecp2 levels in the brain. We now show that in male brain cells, DNA methylation is significantly correlated with the transcript expression of these two isoforms. We show that both Mecp2 isoforms are highly expressed in male neurons compared to male astrocytes, with Mecp2e1 expressed at higher levels than Mecp2e2. Our data indicate that higher DNA methylation at the Mecp2 regulatory element(s) is associated with lower levels of Mecp2 isoforms in male astrocytes compared to male neurons.


Assuntos
Astrócitos/metabolismo , Metilação de DNA , Proteína 2 de Ligação a Metil-CpG/metabolismo , Neurônios/metabolismo , Animais , Astrócitos/citologia , Encéfalo/metabolismo , Encéfalo/patologia , Células Cultivadas , Ilhas de CpG , Modelos Animais de Doenças , Feminino , Genes Ligados ao Cromossomo X , Masculino , Proteína 2 de Ligação a Metil-CpG/genética , Camundongos , Transtornos do Neurodesenvolvimento/metabolismo , Transtornos do Neurodesenvolvimento/patologia , Neurônios/citologia , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo
16.
Nat Commun ; 10(1): 1726, 2019 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-30979904

RESUMO

Ten-eleven-translocation (TET) proteins catalyze DNA hydroxylation, playing an important role in demethylation of DNA in mammals. Remarkably, although hydroxymethylation levels are high in the mouse brain, the potential role of TET proteins in adult neurogenesis is unknown. We show here that a non-catalytic action of TET3 is essentially required for the maintenance of the neural stem cell (NSC) pool in the adult subventricular zone (SVZ) niche by preventing premature differentiation of NSCs into non-neurogenic astrocytes. This occurs through direct binding of TET3 to the paternal transcribed allele of the imprinted gene Small nuclear ribonucleoprotein-associated polypeptide N (Snrpn), contributing to transcriptional repression of the gene. The study also identifies BMP2 as an effector of the astrocytic terminal differentiation mediated by SNRPN. Our work describes a novel mechanism of control of an imprinted gene in the regulation of adult neurogenesis through an unconventional role of TET3.


Assuntos
Diferenciação Celular , Proteínas de Ligação a DNA/metabolismo , Células-Tronco Neurais/citologia , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Centrais de snRNP/metabolismo , Animais , Astrócitos/citologia , Encéfalo/metabolismo , Catálise , Ventrículos Laterais/metabolismo , Camundongos , RNA Interferente Pequeno/metabolismo , Transdução de Sinais
17.
Biomater Sci ; 7(5): 1995-2008, 2019 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-30839020

RESUMO

Neural stem cell (NSC) transplantation exerts a therapeutic effect on spinal cord injury (SCI) but is limited to an unregulated differentiation pattern by which NSCs preferentially differentiate into astrocytes, with relatively few neurons. It is well established that the increased NSC-derived astrocytes exhibit aberrant axonal sprouting associated with allodynia-like symptoms of the forepaws. Some strategies have been used to overcome this issue, such as regulation of major pathways, ex vivo gene transfer, and genetic overexpression. However, lack of efficiency, viral vector safety issues and the risk of tumorigenesis have hindered the clinical application of these treatments. Here, we show that astrocytic differentiation of NSCs in vitro and in vivo can be inhibited by encapsulation of cells in a three-dimensional chondroitin sulfate methacrylate (CSMA) hydrogel. When CSMA hydrogels were used to transplant NSCs, the combinatory implant promoted functional recovery and attenuated the hypersensitivity responses of the forepaws. Further analysis showed that transplantation of NSCs within CSMA hydrogels reduced injured cavity areas and promoted neurogenesis rather than fibroglial formation after graft implantation. Furthermore, the treatment prevented allodynia-related CGRP/GAP43-positive nociception due to fibers sprouting into inappropriate lamina regions. Taken together, these findings show that CSMA/NSCs combined transplantation helps prevent adverse side effects of NSCs treatment and promotes recovery of SCI.


Assuntos
Astrócitos/citologia , Diferenciação Celular/efeitos dos fármacos , Sulfatos de Condroitina/farmacologia , Hidrogéis/química , Metacrilatos/química , Células-Tronco Neurais/transplante , Traumatismos da Medula Espinal/patologia , Animais , Astrócitos/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Sulfatos de Condroitina/química , Feminino , Neurogênese/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Recuperação de Função Fisiológica/efeitos dos fármacos , Traumatismos da Medula Espinal/fisiopatologia
18.
Methods Mol Biol ; 1942: 101-121, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30900179

RESUMO

Patient-derived or genomically modified human induced pluripotent stem cells (iPSCs) offer the opportunity to study neurodevelopmental and neurodegenerative disorders. Overexpression of certain neurogenic transcription factors (TFs) in iPSCs can induce efficient differentiation into homogeneous populations of the disease-relevant neuronal cell types. Here we provide protocols for genomic manipulations of iPSCs by CRISPR/Cas9. We also introduce two methods, based on lentiviral delivery and the piggyBac transposon system, to stably integrate neurogenic TFs into human iPSCs. Furthermore, we describe the TF-mediated neuronal differentiation and maturation in combination with astrocyte cocultures.


Assuntos
Astrócitos/citologia , Sistemas CRISPR-Cas , Células-Tronco Pluripotentes Induzidas/citologia , Doenças Neurodegenerativas/terapia , Transtornos do Neurodesenvolvimento/terapia , Neurônios/citologia , Fatores de Transcrição/genética , Diferenciação Celular , Técnicas de Cocultura , Humanos , Células-Tronco Pluripotentes Induzidas/transplante , Doenças Neurodegenerativas/genética , Transtornos do Neurodesenvolvimento/genética , Neurônios/transplante , Fatores de Transcrição/antagonistas & inibidores
19.
Methods Mol Biol ; 1936: 311-331, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30820907

RESUMO

Human glial progenitor cells (hGPCs) can engraft, expand, and differentiate into functional oligodendrocytes and astrocytes when transplanted neonatally into murine hosts, in which they outcompete the host glial pool to ultimately colonize and dominate the recipient brains. When congenitally hypomyelinated mutants are used as hosts, the donor hGPCs generate myelinogenic oligodendrocytes as well as astrocytes, so that the recipient mice develop a largely humanized white matter, with entirely human-derived myelin. In addition, by neonatally engrafting hGPCs derived from patient- and disease-specific pluripotent stem cells, glial chimeric mice may be produced in which large proportions of all macroglial cells are not only human but also patient and disease specific. Human glial chimeric mice thus provide intriguing preparations by which to investigate the species-specific contributions of human glia to both cognition and human-selective neurodegenerative and neuropsychiatric diseases, as well as the potential for therapeutic glial cell replacement in these disorders. This review presents an overview of the uses, characteristics, and limitations of the human glial chimeric brain model, while providing a step-by-step protocol for the establishment of these mice.


Assuntos
Doenças Neurodegenerativas/patologia , Neuroglia/patologia , Animais , Astrócitos/citologia , Quimera , Modelos Animais de Doenças , Humanos , Camundongos , Neuroglia/citologia , Oligodendroglia/citologia , Células-Tronco Pluripotentes/citologia , Substância Branca/patologia
20.
J Zhejiang Univ Sci B ; 20(3): 205-218, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30829009

RESUMO

Spinal cord injury (SCI), which is much in the public eye, is still a refractory disease compromising the well-being of both patients and society. In spite of there being many methods dealing with the lesion, there is still a deficiency in comprehensive strategies covering all facets of this damage. Further, we should also mention the structure called the corticospinal tract (CST) which plays a crucial role in the motor responses of organisms, and it will be the focal point of our attention. In this review, we discuss a variety of strategies targeting different dimensions following SCI and some treatments that are especially efficacious to the CST are emphasized. Over recent decades, researchers have developed many effective tactics involving five approaches: (1) tackle more extensive regions; (2) provide a regenerative microenvironment; (3) provide a glial microenvironment; (4) transplantation; and (5) other auxiliary methods, for instance, rehabilitation training and electrical stimulation. We review the basic knowledge on this disease and correlative treatments. In addition, some well-formulated perspectives and hypotheses have been delineated. We emphasize that such a multifaceted problem needs combinatorial approaches, and we analyze some discrepancies in past studies. Finally, for the future, we present numerous brand-new latent tactics which have great promise for curbing SCI.


Assuntos
Tratos Piramidais/patologia , Medicina Regenerativa/métodos , Traumatismos da Medula Espinal/terapia , Animais , Astrócitos/citologia , Axônios/fisiologia , Transplante de Células , Modelos Animais de Doenças , Estimulação Elétrica , Humanos , Microglia/citologia , Neurônios Motores/citologia , Regeneração Nervosa , Neuroglia/citologia , Plasticidade Neuronal , Neurônios/citologia , Oligodendroglia/citologia , Recuperação de Função Fisiológica
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