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1.
Biochim Biophys Acta Gen Subj ; 1865(1): 129776, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33127433

RESUMO

BACKGROUND: Protein arginine methyltransferase 1 (PRMT1), a major type I arginine methyltransferase in mammals, methylates histone and non-histone proteins to regulate various cellular functions such as transcription, DNA damage response, and signal transduction. SCOPE OF REVIEW: This review summarizes previous and recent studies on PRMT1 functions in major cell types of the central nervous system. We also discuss the potential involvement of PRMT1 in neurodegenerative diseases such as amyotrophic lateral sclerosis and frontotemporal dementia. Also, we raise key questions that must be addressed in the future to more precisely understand the roles of PRMT1. MAJOR CONCLUSIONS: Recent studies revealed that PRMT1 is essential for the development of neurons, astrocytes, and oligodendrocytes, although further investigation using cell type-specific PRMT1-deficient animals is required. In addition, the relevance of PRMT1 in neurodegenerative diseases will continue to be a hot topic. GENERAL SIGNIFICANCE: PRMT1 is important for neural development and neurodegenerative diseases.


Assuntos
Arginina/metabolismo , Encéfalo/crescimento & desenvolvimento , Doenças Neurodegenerativas/metabolismo , Proteína-Arginina N-Metiltransferases/metabolismo , Proteínas Repressoras/metabolismo , Animais , Arginina/análogos & derivados , Arginina/genética , Encéfalo/metabolismo , Encéfalo/patologia , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Metilação , Células-Tronco Neurais/metabolismo , Células-Tronco Neurais/patologia , Doenças Neurodegenerativas/genética , Doenças Neurodegenerativas/patologia , Proteína-Arginina N-Metiltransferases/genética , Proteínas Repressoras/genética
2.
Life Sci ; 260: 118388, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32890602

RESUMO

Damage to the cholinergic system in central nervous system injuries such as traumatic brain injury (TBI) and neurodegenerative diseases leads to impaired learning and cognition. Neural stem cells (NSCs) have self-renewal capacity and multi-directional differentiation potential and considered the best source of cells for cell replacement therapy. However, how to promote the differentiation of NSCs into neurons is a major challenge in current research. Lhx8 has a specific effect on the development of the cholinergic nervous system, but its exact function is unclear. In this study, we found that Lhx8 could regulate the expression of Growth arrest-specific (GAS)5 which has been implicated in cancer but was less studied in the nervous system. Additionally, results from PCR, fluorescence in situ hybridization, and immunocytochemical analyses showed that GAS5 is mainly expressed in the cytoplasm of hippocampal neural stems cells and promotes their differentiation into neurons; the Morris water maze test demonstrated that GAS5 overexpression restored learning and memory in rats with cholinergic injury. These findings indicate that GAS5, which is regulated by Lhx8, improve brain function following cholinergic nerve injury.


Assuntos
Lesões Encefálicas/fisiopatologia , Neurônios Colinérgicos/patologia , Proteínas com Homeodomínio LIM/metabolismo , Aprendizagem/fisiologia , Memória/fisiologia , Células-Tronco Neurais/patologia , RNA Longo não Codificante/genética , Fatores de Transcrição/metabolismo , Acetilcolina/metabolismo , Animais , Colina O-Acetiltransferase/metabolismo , Neurônios Colinérgicos/metabolismo , Regulação da Expressão Gênica , Proteínas com Homeodomínio LIM/genética , Células-Tronco Neurais/metabolismo , Ratos , Ratos Sprague-Dawley , Recuperação de Função Fisiológica , Fatores de Transcrição/genética
3.
Nat Commun ; 11(1): 4038, 2020 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-32788587

RESUMO

Asparaginyl-tRNA synthetase1 (NARS1) is a member of the ubiquitously expressed cytoplasmic Class IIa family of tRNA synthetases required for protein translation. Here, we identify biallelic missense and frameshift mutations in NARS1 in seven patients from three unrelated families with microcephaly and neurodevelopmental delay. Patient cells show reduced NARS1 protein, impaired NARS1 activity and impaired global protein synthesis. Cortical brain organoid modeling shows reduced proliferation of radial glial cells (RGCs), leading to smaller organoids characteristic of microcephaly. Single-cell analysis reveals altered constituents of both astrocytic and RGC lineages, suggesting a requirement for NARS1 in RGC proliferation. Our findings demonstrate that NARS1 is required to meet protein synthetic needs and to support RGC proliferation in human brain development.


Assuntos
Aspartato-tRNA Ligase/deficiência , Aspartato-tRNA Ligase/genética , Córtex Cerebral/patologia , Microcefalia/genética , Células-Tronco Neurais/patologia , Organoides/patologia , Aminoacil-RNA de Transferência/genética , Adolescente , Adulto , Sequência de Bases , Diferenciação Celular , Proliferação de Células , Tamanho Celular , Sobrevivência Celular , Criança , Família , Feminino , Fibroblastos/metabolismo , Fibroblastos/patologia , Células HEK293 , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Antígeno Ki-67/metabolismo , Masculino , Mutação/genética , Células-Tronco Neurais/metabolismo , Neuroglia/metabolismo , Linhagem , Adulto Jovem
4.
J Vis Exp ; (162)2020 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-32831302

RESUMO

Neurite outgrowth assay and neurotoxicity assessment are two major studies that can be performed using the presented method herein. This protocol provides reliable analysis of neuronal morphology together with quantitative measurements of modifications on neurite length and synaptic protein localization and abundance upon treatment with small molecule compounds. In addition to the application of the presented method in neurite outgrowth studies, neurotoxicity assessment can be performed to assess, distinguish and rank commercial chemical compounds based on their potential developmental neurotoxicity effect. Even though cell lines are nowadays widely used in compound screening assays in neuroscience, they often differ genetically and phenotypically from their tissue origin. Primary cells, on the other hand, maintain important markers and functions observed in vivo. Therefore, due to the translation potential and physiological relevance that these cells could offer neurite outgrowth assay and neurotoxicity assessment can considerably benefit from using human neural progenitor cells (hNPCs) as the primary human cell model. The presented method herein can be utilized to screen for the ability of compounds to induce neurite outgrowth and neurotoxicity by taking advantage of the human neural progenitor cell-derived neurons, a cell model closely representing human biology."


Assuntos
Bioensaio/métodos , Células-Tronco Neurais/patologia , Crescimento Neuronal , Neurônios/patologia , Neurotoxinas/toxicidade , Animais , Diferenciação Celular/efeitos dos fármacos , Permeabilidade da Membrana Celular/efeitos dos fármacos , Separação Celular , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Epigênese Genética/efeitos dos fármacos , Fluorescência , Congelamento , Humanos , Células-Tronco Neurais/efeitos dos fármacos , Crescimento Neuronal/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Software , Coloração e Rotulagem
6.
Life Sci ; 256: 118031, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32615186

RESUMO

AIMS: We had previously reported that addition of putrescine to the culture medium was reported to reduce methylmercury toxicity in C17.2 neural stem cells. Here, we have examined the inhibition of methylmercury-induced cytotoxicity by putrescine using ODC1-overexpressing C17.2 cells. MATERIALS AND METHODS: We established stable ODC1-overexpressing C17.2 cells and evaluated methylmercury-induced apoptosis by examining the TUNEL assay and cleaved caspase-3 levels. Mitochondria-mediated apoptosis was also evaluated by reduction of mitochondrial membrane potential and recruitment of Bax and Bak to the mitochondria. KEY FINDINGS: ODC is encoded by ODC1 gene, and putrescine levels in ODC1-overexpressing cells were significantly higher than in control cells. Overexpression of ODC1 and addition of putrescine to the culture medium suppressed DNA fragmentation and caspase-3 activation, which are observed when apoptosis is induced by methylmercury. Moreover, mitochondrial dysfunction and reactive oxygen species (ROS) generation, caused by methylmercury, were also inhibited by the overexpression of ODC1 and putrescine; pretreatment with ODC inhibitor, however, promoted both ROS generation and apoptosis by methylmercury. Finally, we found that Bax and Bak, the apoptosis-promoting factors, to be increased in mitochondria, following methylmercury treatment, and the same was inhibited by overexpression of ODC1. These results suggest that overexpression of ODC1 may prevent mitochondria-mediated apoptosis by methylmercury via increase of putrescine levels. SIGNIFICANCE: Our findings provide important clues to clarify mechanisms involved in the defense against methylmercury toxicity and suggest novel biological functions of putrescine.


Assuntos
Compostos de Metilmercúrio/toxicidade , Mitocôndrias/efeitos dos fármacos , Células-Tronco Neurais/efeitos dos fármacos , Ornitina Descarboxilase/genética , Putrescina/farmacologia , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Marcação In Situ das Extremidades Cortadas , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Mitocôndrias/patologia , Células-Tronco Neurais/patologia
7.
Proc Natl Acad Sci U S A ; 117(32): 19578-19589, 2020 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-32727894

RESUMO

The CreER/LoxP system is widely accepted to track neural lineages and study gene functions upon tamoxifen (TAM) administration. We have observed that prenatal TAM treatment caused high rates of delayed delivery and fetal mortality. This substance could produce undesired results, leading to data misinterpretation. Here, we report that administration of TAM during early stages of cortical neurogenesis promoted precocious neural differentiation, while it inhibited neural progenitor cell (NPC) proliferation. The TAM-induced inhibition of NPC proliferation led to deficits in cortical neurogenesis, dendritic morphogenesis, synaptic formation, and cortical patterning in neonatal and postnatal offspring. Mechanistically, by employing single-cell RNA-sequencing (scRNA-seq) analysis combined with in vivo and in vitro assays, we show TAM could exert these drastic effects mainly through dysregulating the Wnt-Dmrta2 signaling pathway. In adult mice, administration of TAM significantly attenuated NPC proliferation in both the subventricular zone and the dentate gyrus. This study revealed the cellular and molecular mechanisms for the adverse effects of TAM on corticogenesis, suggesting that care must be taken when using the TAM-induced CreER/LoxP system for neural lineage tracing and genetic manipulation studies in both embryonic and adult brains.


Assuntos
Encéfalo/efeitos dos fármacos , Neurogênese/efeitos dos fármacos , Efeitos Tardios da Exposição Pré-Natal/patologia , Tamoxifeno/efeitos adversos , Animais , Encéfalo/embriologia , Encéfalo/patologia , Diferenciação Celular , Proliferação de Células , Giro Denteado/efeitos dos fármacos , Giro Denteado/patologia , Feminino , Ventrículos Laterais/efeitos dos fármacos , Ventrículos Laterais/patologia , Camundongos , Células-Tronco Neurais/efeitos dos fármacos , Células-Tronco Neurais/patologia , Gravidez , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , RNA-Seq , Análise de Célula Única , Fatores de Transcrição/metabolismo , Via de Sinalização Wnt/efeitos dos fármacos
8.
Mol Cell ; 78(2): 346-358.e9, 2020 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-32268123

RESUMO

CAG-repeat expansions in at least eight different genes cause neurodegeneration. The length of the extended polyglutamine stretches in the corresponding proteins is proportionally related to their aggregation propensity. Although these proteins are ubiquitously expressed, they predominantly cause toxicity to neurons. To understand this neuronal hypersensitivity, we generated induced pluripotent stem cell (iPSC) lines of spinocerebellar ataxia type 3 and Huntington's disease patients. iPSC generation and neuronal differentiation are unaffected by polyglutamine proteins and show no spontaneous aggregate formation. However, upon glutamate treatment, aggregates form in neurons but not in patient-derived neural progenitors. During differentiation, the chaperone network is drastically rewired, including loss of expression of the anti-amyloidogenic chaperone DNAJB6. Upregulation of DNAJB6 in neurons antagonizes glutamate-induced aggregation, while knockdown of DNAJB6 in progenitors results in spontaneous polyglutamine aggregation. Loss of DNAJB6 expression upon differentiation is confirmed in vivo, explaining why stem cells are intrinsically protected against amyloidogenesis and protein aggregates are dominantly present in neurons.


Assuntos
Proteínas Amiloidogênicas/genética , Diferenciação Celular/genética , Proteínas de Choque Térmico HSP40/genética , Chaperonas Moleculares/genética , Proteínas do Tecido Nervoso/genética , Células-Tronco Neurais/metabolismo , Regulação da Expressão Gênica/genética , Técnicas de Inativação de Genes , Ácido Glutâmico/metabolismo , Humanos , Doença de Huntington/genética , Doença de Huntington/metabolismo , Doença de Huntington/patologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Células-Tronco Pluripotentes Induzidas/patologia , Doença de Machado-Joseph/genética , Doença de Machado-Joseph/metabolismo , Doença de Machado-Joseph/patologia , Células-Tronco Neurais/patologia , Neurônios/metabolismo , Neurônios/patologia , Agregados Proteicos/genética , Expansão das Repetições de Trinucleotídeos/genética
9.
Mol Cell ; 78(2): 329-345.e9, 2020 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-32268122

RESUMO

Neural stem and progenitor cells (NSPCs) are critical for continued cellular replacement in the adult brain. Lifelong maintenance of a functional NSPC pool necessitates stringent mechanisms to preserve a pristine proteome. We find that the NSPC chaperone network robustly maintains misfolded protein solubility and stress resilience through high levels of the ATP-dependent chaperonin TRiC/CCT. Strikingly, NSPC differentiation rewires the cellular chaperone network, reducing TRiC/CCT levels and inducing those of the ATP-independent small heat shock proteins (sHSPs). This switches the proteostasis strategy in neural progeny cells to promote sequestration of misfolded proteins into protective inclusions. The chaperone network of NSPCs is more effective than that of differentiated cells, leading to improved management of proteotoxic stress and amyloidogenic proteins. However, NSPC proteostasis is impaired by brain aging. The less efficient chaperone network of differentiated neural progeny may contribute to their enhanced susceptibility to neurodegenerative diseases characterized by aberrant protein misfolding and aggregation.


Assuntos
Envelhecimento/genética , Chaperonas Moleculares/genética , Células-Tronco Neurais/metabolismo , Agregação Patológica de Proteínas/genética , Trifosfato de Adenosina/genética , Envelhecimento/patologia , Animais , Encéfalo/crescimento & desenvolvimento , Encéfalo/patologia , Diferenciação Celular/genética , Chaperoninas/genética , Regulação da Expressão Gênica no Desenvolvimento/genética , Redes Reguladoras de Genes/genética , Camundongos , Chaperonas Moleculares/metabolismo , Células-Tronco Neurais/patologia , Dobramento de Proteína , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crescimento & desenvolvimento , Células-Tronco/metabolismo , Células-Tronco/patologia
10.
Mol Cell ; 77(5): 1124-1142.e10, 2020 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-32142685

RESUMO

The ubiquitin ligase Parkin, protein kinase PINK1, USP30 deubiquitylase, and p97 segregase function together to regulate turnover of damaged mitochondria via mitophagy, but our mechanistic understanding in neurons is limited. Here, we combine induced neurons (iNeurons) derived from embryonic stem cells with quantitative proteomics to reveal the dynamics and specificity of Parkin-dependent ubiquitylation under endogenous expression conditions. Targets showing elevated ubiquitylation in USP30-/- iNeurons are concentrated in components of the mitochondrial translocon, and the ubiquitylation kinetics of the vast majority of Parkin targets are unaffected, correlating with a modest kinetic acceleration in accumulation of pS65-Ub and mitophagic flux upon mitochondrial depolarization without USP30. Basally, ubiquitylated translocon import substrates accumulate, suggesting a quality control function for USP30. p97 was dispensable for Parkin ligase activity in iNeurons. This work provides an unprecedented quantitative landscape of the Parkin-modified ubiquitylome in iNeurons and reveals the underlying specificity of central regulatory elements in the pathway.


Assuntos
Células-Tronco Embrionárias Humanas/enzimologia , Mitocôndrias/enzimologia , Proteínas Mitocondriais/metabolismo , Mitofagia , Células-Tronco Neurais/enzimologia , Neurogênese , Neurônios/enzimologia , Tioléster Hidrolases/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Células HeLa , Células-Tronco Embrionárias Humanas/patologia , Humanos , Cinética , Mitocôndrias/genética , Mitocôndrias/patologia , Proteínas Mitocondriais/genética , Células-Tronco Neurais/patologia , Neurônios/patologia , Fosforilação , Proteínas Quinases/genética , Proteínas Quinases/metabolismo , Proteômica , Transdução de Sinais , Tioléster Hidrolases/genética , Ubiquitina-Proteína Ligases/genética , Ubiquitinação , Proteína com Valosina/genética , Proteína com Valosina/metabolismo
11.
Int J Mol Sci ; 21(4)2020 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-32070035

RESUMO

Cadherin epidermal growth factor (EGF) laminin G (LAG) seven-pass G-type receptor 1 (CELSR1) is a member of a special subgroup of adhesion G protein-coupled receptors. Although Celsr1 has been reported to be a sensitive gene for stroke, the effect of CELSR1 in ischemic stroke is still not known. Here, we investigated the effect of CELSR1 on neuroprotection, neurogenesis and angiogenesis in middle cerebral artery occlusion (MCAO) rats. The mRNA expression of Celsr1 was upregulated in the subventricular zone (SVZ), hippocampus and ischemic penumbra after cerebral ischemic injury. Knocking down the expression of Celsr1 in the SVZ with a lentivirus significantly reduced the proliferation of neuroblasts, the number of CD31-positive cells, motor function and rat survival and increased cell apoptosis and the infarct volume in MCAO rats. In addition, the expression of p-PKC in the SVZ and peri-infarct tissue was downregulated after ischemia/ reperfusion. Meanwhile, in the dentate gyrus of the hippocampus, knocking down the expression of Celsr1 significantly reduced the proliferation of neuroblasts; however, it had no influence on motor function, cell apoptosis or angiogenesis. These data indicate that CELSR1 has a neuroprotective effect on cerebral ischemia injury by reducing cell apoptosis in the peri-infarct cerebral cortex and promoting neurogenesis and angiogenesis, mainly through the Wnt/PKC pathway.


Assuntos
Isquemia Encefálica/genética , Caderinas/genética , Neurogênese/genética , Acidente Vascular Cerebral/genética , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Isquemia Encefálica/patologia , Proliferação de Células/genética , Modelos Animais de Doenças , Regulação da Expressão Gênica/genética , Hipocampo/metabolismo , Hipocampo/patologia , Humanos , Infarto da Artéria Cerebral Média/genética , Infarto da Artéria Cerebral Média/patologia , Ventrículos Laterais/metabolismo , Ventrículos Laterais/patologia , Células-Tronco Neurais/metabolismo , Células-Tronco Neurais/patologia , Fármacos Neuroprotetores/metabolismo , RNA Mensageiro/genética , Ratos , Acidente Vascular Cerebral/patologia , Via de Sinalização Wnt/genética
12.
Artif Cells Nanomed Biotechnol ; 48(1): 594-601, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32052645

RESUMO

Background: Hypoxic-ischaemic encephalopathy (HIE) is a prevailing severe brain damage disease in newborns, and caused by perinatal asphyxia cerebral ischaemia and reperfusion. Here, we investigated the role of cZNF292 in oxygen-glucose deprivation/reperfusion (OGD/R)-induced neural stem cells (NSCs) injury, and explored the underlying molecular mechanism.Methods: Before NSCs were subjected to OGD/R treatment, NSCs were transfected with or without overexpressing cZNF292, si-cZNF292 or miR-22 inhibitor. Viability, apoptosis and potential molecular mechanism were examined. Cell viability and apoptotic rate were evaluated utilizing cell counting kit-8 (CCK-8) and flow cytometry. The cZNF292 and miR-22 expression was determined utilizing quantitative reverse transcription-PCR (qRT-PCR). Moreover, apoptosis and Wnt/ß-catenin and PKC/ERK pathways-associated proteins were quantified applying western blot.Results: OGD/R repressed viability and promoted apoptosis of NSCs. Also, cZNF292 expression was promoted by OGD/R treatment. Moreover, cZNF292 overexpression further caused OGD/R-stimulated damage. Inversely, silencing cZNF292 alleviated OGD/R-stimulated damage in NSCs. In addition, miR-22 expression was negatively regulated by cZNF292. It was confirmed that silencing cZNF292 attenuated OGD/R-induced NSCs injury and promoted the activation of Wnt/ß-catenin and PKC/ERK pathways via the up-regulation of miR-22.Conclusions: The cZNF292 silence alleviated OGD/R-induced injury through the up-regulation of miR-22 in NSCs, and which furnished the theoretical basis for further research on HIE progression.


Assuntos
MicroRNAs/genética , Células-Tronco Neurais/metabolismo , Interferência de RNA , RNA Circular/genética , Traumatismo por Reperfusão/prevenção & controle , Animais , Apoptose , Sobrevivência Celular , Células Cultivadas , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Regulação da Expressão Gênica , Glucose/metabolismo , MicroRNAs/antagonistas & inibidores , MicroRNAs/metabolismo , Células-Tronco Neurais/patologia , Oxigênio/metabolismo , Proteína Quinase C/metabolismo , Ratos , Traumatismo por Reperfusão/genética , Traumatismo por Reperfusão/metabolismo , Transdução de Sinais , Proteína Wnt3A/metabolismo , beta Catenina/metabolismo
13.
J Neurosci ; 40(7): 1483-1500, 2020 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-31911460

RESUMO

Myelin loss limits neurological recovery and myelin regeneration and is critical for restoration of function. We recently discovered that global knock-out of the thrombin receptor, also known as Protease Activated Receptor 1 (PAR1), accelerates myelin development. Here we demonstrate that knocking out PAR1 also promotes myelin regeneration. Outcomes in two unique models of myelin injury and repair, that is lysolecithin or cuprizone-mediated demyelination, showed that PAR1 knock-out in male mice improves replenishment of myelinating cells and remyelinated nerve fibers and slows early axon damage. Improvements in myelin regeneration in PAR1 knock-out mice occurred in tandem with a skewing of reactive astrocyte signatures toward a prorepair phenotype. In cell culture, the promyelinating effects of PAR1 loss of function are consistent with possible direct effects on the myelinating potential of oligodendrocyte progenitor cells (OPCs), in addition to OPC-indirect effects involving enhanced astrocyte expression of promyelinating factors, such as BDNF. These findings highlight previously unrecognized roles of PAR1 in myelin regeneration, including integrated actions across the oligodendrocyte and astroglial compartments that are at least partially mechanistically linked to the powerful BDNF-TrkB neurotrophic signaling system. Altogether, findings suggest PAR1 may be a therapeutically tractable target for demyelinating disorders of the CNS.SIGNIFICANCE STATEMENT Replacement of oligodendroglia and myelin regeneration holds tremendous potential to improve function across neurological conditions. Here we demonstrate Protease Activated Receptor 1 (PAR1) is an important regulator of the capacity for myelin regeneration across two experimental murine models of myelin injury. PAR1 is a G-protein-coupled receptor densely expressed in the CNS, however there is limited information regarding its physiological roles in health and disease. Using a combination of PAR1 knock-out mice, oligodendrocyte monocultures and oligodendrocyte-astrocyte cocultures, we demonstrate blocking PAR1 improves myelin production by a mechanism related to effects across glial compartments and linked in part to regulatory actions toward growth factors such as BDNF. These findings set the stage for development of new clinically relevant myelin regeneration strategies.


Assuntos
Doenças Desmielinizantes/fisiopatologia , Regeneração Nervosa/efeitos dos fármacos , Receptor PAR-1/antagonistas & inibidores , Animais , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Astrócitos/patologia , Axônios/patologia , Fator Neurotrófico Derivado do Encéfalo/biossíntese , Fator Neurotrófico Derivado do Encéfalo/farmacologia , Quelantes/toxicidade , Técnicas de Cocultura , Cobre , Corpo Caloso/efeitos dos fármacos , Corpo Caloso/patologia , Cuprizona/toxicidade , Doenças Desmielinizantes/induzido quimicamente , Perfilação da Expressão Gênica , Lisofosfatidilcolinas/toxicidade , Masculino , Camundongos , Camundongos Knockout , Bainha de Mielina/fisiologia , Regeneração Nervosa/fisiologia , Células-Tronco Neurais/efeitos dos fármacos , Células-Tronco Neurais/patologia , Oligodendroglia/efeitos dos fármacos , Oligodendroglia/metabolismo , Oligodendroglia/patologia , Receptor PAR-1/deficiência , Receptor PAR-1/fisiologia , Teste de Desempenho do Rota-Rod , Medula Espinal/efeitos dos fármacos , Medula Espinal/patologia , Substância Branca/efeitos dos fármacos , Substância Branca/patologia
14.
PLoS Biol ; 18(1): e3000585, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31905199

RESUMO

It was recently suggested that supplying the brain with new neurons could counteract Alzheimer's disease (AD). This provocative idea requires further testing in experimental models in which the molecular basis of disease-induced neuronal regeneration could be investigated. We previously found that zebrafish stimulates neural stem cell (NSC) plasticity and neurogenesis in AD and could help to understand the mechanisms to be harnessed for developing new neurons in diseased mammalian brains. Here, by performing single-cell transcriptomics, we found that amyloid toxicity-induced interleukin-4 (IL4) promotes NSC proliferation and neurogenesis by suppressing the tryptophan metabolism and reducing the production of serotonin. NSC proliferation was suppressed by serotonin via down-regulation of brain-derived neurotrophic factor (BDNF)-expression in serotonin-responsive periventricular neurons. BDNF enhances NSC plasticity and neurogenesis via nerve growth factor receptor A (NGFRA)/ nuclear factor 'kappa-light-chain-enhancer' of activated B-cells (NFkB) signaling in zebrafish but not in rodents. Collectively, our results suggest a complex neuron-glia interaction that regulates regenerative neurogenesis after AD conditions in zebrafish.


Assuntos
Doença de Alzheimer , Comunicação Celular/fisiologia , Regeneração Nervosa/fisiologia , Neurogênese/fisiologia , Neuroglia/fisiologia , Neurônios/fisiologia , Fatores Etários , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Doença de Alzheimer/fisiopatologia , Animais , Animais Geneticamente Modificados , Encéfalo/metabolismo , Encéfalo/fisiologia , Fator Neurotrófico Derivado do Encéfalo/genética , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Modelos Animais de Doenças , Masculino , Camundongos , Camundongos Transgênicos , Regeneração Nervosa/genética , Células-Tronco Neurais/patologia , Células-Tronco Neurais/fisiologia , Neuroimunomodulação/fisiologia , Plasticidade Neuronal/fisiologia , Receptores de Fator de Crescimento Neural/genética , Receptores de Fator de Crescimento Neural/metabolismo , Serotonina/genética , Serotonina/metabolismo , Transdução de Sinais/genética , Peixe-Zebra , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
15.
Dev Cell ; 52(3): 294-308.e3, 2020 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-31978324

RESUMO

The ability of XIST to dosage compensate a trisomic autosome presents unique experimental opportunities and potentially transformative therapeutic prospects. However, it is currently thought that XIST requires the natural context surrounding pluripotency to initiate chromosome silencing. Here, we demonstrate that XIST RNA induced in differentiated neural cells can trigger chromosome-wide silencing of chromosome 21 in Down syndrome patient-derived cells. Use of this tightly controlled system revealed a deficiency in differentiation of trisomic neural stem cells to neurons, correctible by inducing XIST at different stages of neurogenesis. Single-cell transcriptomics and other analyses strongly implicate elevated Notch signaling due to trisomy 21, thereby promoting neural stem cell cycling that delays terminal differentiation. These findings have significance for illuminating the epigenetic plasticity of cells during development, the understanding of how human trisomy 21 effects Down syndrome neurobiology, and the translational potential of XIST, a unique non-coding RNA.


Assuntos
Diferenciação Celular , Síndrome de Down/patologia , Inativação Gênica , Células-Tronco Neurais/patologia , Neurogênese , Neurônios/patologia , RNA Longo não Codificante/metabolismo , Células Cultivadas , Compensação de Dosagem (Genética) , Síndrome de Down/genética , Síndrome de Down/metabolismo , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Células-Tronco Pluripotentes Induzidas/patologia , Masculino , Células-Tronco Neurais/metabolismo , Neurônios/metabolismo , RNA Longo não Codificante/genética , Receptores Notch/genética , Receptores Notch/metabolismo , Inativação do Cromossomo X
16.
Sci Adv ; 6(1): eaay6350, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31911949

RESUMO

Temperature homeostasis is critical for fetal development. The heat sensor protein TRPM2 (transient receptor potential channel M2) plays crucial roles in the heat response, but its function and specific mechanism in brain development remain largely unclear. Here, we observe that TRPM2 is expressed in neural stem cells. In hyperthermia, TRPM2 knockdown and knockout reduce the proliferation of neural progenitor cells (NPCs) and, accordingly, increase premature cortical neuron differentiation. In terms of the mechanism, TRPM2 regulates neural progenitor self-renewal by targeting SP5 (specificity protein 5) via inhibiting the phosphorylation of ß-catenin and increasing ß-catenin expression. Furthermore, the constitutive expression of TRPM2 or SP5 partly rescues defective NPC proliferation in the TRPM2-deficient embryonic brain. Together, the data suggest that TRPM2 has a critical function in maintaining the NPC pool during heat stress, and the findings provide a framework for understanding how the disruption of the TRPM2 gene may contribute to neurological disorders.


Assuntos
Desenvolvimento Fetal/genética , Neurogênese/genética , Canais de Cátion TRPM/genética , Fatores de Transcrição/genética , beta Catenina/genética , Animais , Encéfalo/crescimento & desenvolvimento , Encéfalo/patologia , Diferenciação Celular/genética , Proliferação de Células/genética , Autorrenovação Celular/genética , Regulação da Expressão Gênica no Desenvolvimento/genética , Homeostase , Humanos , Hipertermia Induzida , Camundongos , Células-Tronco Neurais/metabolismo , Células-Tronco Neurais/patologia , Neurônios/metabolismo , Neurônios/patologia
17.
Mol Med Rep ; 21(3): 1172-1180, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31922229

RESUMO

Alzheimer's disease (AD) is the most prevalent age­related neurodegenerative disorder. It is featured by the progressive accumulation of ß­amyloid (Aß) plaques and neurofibrillary tangles. This can eventually lead to a decrease of cholinergic neurons in the basal forebrain. Stem cell transplantation is an effective treatment for neurodegenerative diseases. Previous studies have revealed that different types of stem or progenitor cells can mitigate cognition impairment in different Alzheimer's disease mouse models. However, understanding the underlying mechanisms of neural stem cell (NSC) therapies for AD requires further investigation. In the present study, the effects and the underlying mechanisms of the treatment of AD by NSCs are reported. The latter were labelled with the enhanced green fluorescent protein (EGFP) prior to implantation into the bilateral hippocampus of an amyloid precursor protein (APP)/presenilin 1 (PS1) transgenic (Tg) mouse model of AD. It was observed that the number of basal forebrain cholinergic neurons was restored and the expression of choline acetyltransferase (ChAT) protein was increased. Moreover, the levels of synaptophysin (SYP), postsynaptic density protein 95 (PSD­95) and microtubule­associated protein (MAP­2) were significantly increased in the hippocampus of NSC­treated AD mice. Notably, spatial learning and memory were both improved after transplantation of NSCs. In conclusion, the present study revealed that NSC transplantation improved learning and memory functions in an AD mouse model. This treatment allowed repairing of basal forebrain cholinergic neurons and increased the expression of the cognition­related proteins SYP, PSD­95 and MAP­2 in the hippocampus.


Assuntos
Doença de Alzheimer , Neurônios Colinérgicos , Aprendizagem , Memória , Células-Tronco Neurais , Presenilina-1 , Transplante de Células-Tronco , Sinapses , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Doença de Alzheimer/terapia , Amiloide/genética , Amiloide/metabolismo , Animais , Neurônios Colinérgicos/metabolismo , Neurônios Colinérgicos/patologia , Modelos Animais de Doenças , Camundongos , Camundongos Transgênicos , Células-Tronco Neurais/metabolismo , Células-Tronco Neurais/patologia , Células-Tronco Neurais/transplante , Presenilina-1/biossíntese , Presenilina-1/genética , Sinapses/genética , Sinapses/metabolismo , Sinapses/patologia
18.
Protein Cell ; 11(1): 1-22, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31037510

RESUMO

Cockayne syndrome (CS) is a rare autosomal recessive inherited disorder characterized by a variety of clinical features, including increased sensitivity to sunlight, progressive neurological abnormalities, and the appearance of premature aging. However, the pathogenesis of CS remains unclear due to the limitations of current disease models. Here, we generate integration-free induced pluripotent stem cells (iPSCs) from fibroblasts from a CS patient bearing mutations in CSB/ERCC6 gene and further derive isogenic gene-corrected CS-iPSCs (GC-iPSCs) using the CRISPR/Cas9 system. CS-associated phenotypic defects are recapitulated in CS-iPSC-derived mesenchymal stem cells (MSCs) and neural stem cells (NSCs), both of which display increased susceptibility to DNA damage stress. Premature aging defects in CS-MSCs are rescued by the targeted correction of mutant ERCC6. We next map the transcriptomic landscapes in CS-iPSCs and GC-iPSCs and their somatic stem cell derivatives (MSCs and NSCs) in the absence or presence of ultraviolet (UV) and replicative stresses, revealing that defects in DNA repair account for CS pathologies. Moreover, we generate autologous GC-MSCs free of pathogenic mutation under a cGMP (Current Good Manufacturing Practice)-compliant condition, which hold potential for use as improved biomaterials for future stem cell replacement therapy for CS. Collectively, our models demonstrate novel disease features and molecular mechanisms and lay a foundation for the development of novel therapeutic strategies to treat CS.


Assuntos
Senilidade Prematura , Síndrome de Cockayne , DNA Helicases/genética , Enzimas Reparadoras do DNA/genética , Edição de Genes/métodos , Modelos Biológicos , Proteínas de Ligação a Poli-ADP-Ribose/genética , Reparo Gênico Alvo-Dirigido/métodos , Senilidade Prematura/patologia , Senilidade Prematura/terapia , Animais , Sistemas CRISPR-Cas , Células Cultivadas , Síndrome de Cockayne/patologia , Síndrome de Cockayne/terapia , Reparo do DNA , Humanos , Células-Tronco Pluripotentes Induzidas/patologia , Masculino , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/patologia , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Mutação , Células-Tronco Neurais/metabolismo , Células-Tronco Neurais/patologia , Transcriptoma
19.
Cancer Res ; 80(1): 5-16, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31575548

RESUMO

Our understanding of intratumoral heterogeneity in cancer continues to evolve, with current models incorporating single-cell signatures to explore cell-cell interactions and differentiation state. The transition between stem and differentiation states in nonneoplastic cells requires metabolic plasticity, and this plasticity is increasingly recognized to play a central role in cancer biology. The insights from hematopoietic and neural stem cell differentiation pathways were used to identify cancer stem cells in leukemia and gliomas. Similarly, defining metabolic heterogeneity and fuel-switching signals in nonneoplastic stem cells may also give important insights into the corresponding molecular mechanisms controlling metabolic plasticity in cancer. These advances are important, because metabolic adaptation to anticancer therapeutics is rooted in this inherent metabolic plasticity and is a therapeutic challenge to be overcome.


Assuntos
Encéfalo/patologia , Neoplasias/patologia , Células Neoplásicas Circulantes/patologia , Células-Tronco Neoplásicas/patologia , Animais , Encéfalo/citologia , Diferenciação Celular , Hipóxia Celular , Plasticidade Celular , Modelos Animais de Doenças , Ácidos Graxos/metabolismo , Glicólise , Células-Tronco Hematopoéticas/patologia , Humanos , Neoplasias/sangue , Neoplasias/metabolismo , Células Neoplásicas Circulantes/metabolismo , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neurais/patologia , Oxirredução , Oxigênio/metabolismo
20.
Biochim Biophys Acta Mol Basis Dis ; 1866(4): 165533, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-31442530

RESUMO

Human-derived neuronal cell lines are progressively being utilized in understanding neurobiology and preclinical translational research as they are biologically more relevant than rodent-derived cells lines. The Lund human mesencephalic (LUHMES) cell line comprises human neuronal cells that can be differentiated to post-mitotic neurons and is increasingly being used as an in vitro model for various neurodegenerative diseases. A previously published 2-step differentiation procedure leads to the generation of post-mitotic neurons within 5-days, but only a small proportion (10%) of the total cell population tests positive for tyrosine hydroxylase (TH). Here we report on a novel differentiation protocol that we optimized by using a cocktail of neurotrophic factors, pleiotropic cytokines, and antioxidants to effectively generate proportionately more dopaminergic neurons within the same time period. Visualization and quantification of TH-positive cells revealed that under our new protocol, 25% of the total cell population expressed markers of dopaminergic neurons with the TH-positive neuron count peaking on day 5. These neurons showed spontaneous electrical activity and responded to known Parkinsonian toxins as expected by showing decreased cell viability and dopamine uptake and a concomitant increase in apoptotic cell death. Together, our results outline an improved method for generating a higher proportion of dopaminergic neurons, thus making these cells an ideal neuronal culture model of Parkinson's disease (PD) for translational research.


Assuntos
Diferenciação Celular , Neurônios Dopaminérgicos/metabolismo , Modelos Neurológicos , Células-Tronco Neurais/metabolismo , Doença de Parkinson/metabolismo , Pesquisa Médica Translacional , Antígenos de Diferenciação/biossíntese , Linhagem Celular , Neurônios Dopaminérgicos/patologia , Humanos , Células-Tronco Neurais/patologia , Doença de Parkinson/patologia , Doença de Parkinson/terapia
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