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1.
Ecotoxicol Environ Saf ; 183: 109498, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31377521

RESUMO

2',2',4,4'-tetrabromo diphenyl ether (BDE-47), one of the most abundant congeners of commercial pentaBDE utilized as flame retardants, has been phased out of production due to its potential neural toxicity and endocrine disrupting activities, and yet still present in the environment. Several alternatives to BDE-47, including tetrabromobisphenol A (TBBPA), tetrabromobisphenol S (TBBPS), tetrachlorobisphenol A (TCBPA) and decabromodiphenyl ether (BDE-209), are presently employed without restrictions and their potential toxic effects on human neural development are still unclear. In this study, we utilized a human neural stem cell (hNSC)-based system to evaluate the potential developmental neurotoxic effects of the above-mentioned five chemicals, at environment and human exposure relevant concentrations. We found that those compounds slightly altered the expression of hNSC identity markers (SOX2, SOX3 and NES), without impairing cell viability or proliferation, in part by either modulating glycogen synthase kinase 3 beta (GSK3ß) signaling (TBBPS, TCBPA and BDE-47), and slightly disturbing the NOTCH pathway (TBBPA, TBBPS and TCBPA). Moreover, the five chemicals seemed to alter hNSC differentiation by perturbing triiodothyronine (T3) cellular signaling. Thus, our findings suggest that the five compounds, especially TBBPS, TCBPA, and BDE-47, may affect hNSC self-renewal and differentiation abilities and potentially elicit neural developmental toxicity.


Assuntos
Retardadores de Chama/toxicidade , Regulação da Expressão Gênica/efeitos dos fármacos , Glicogênio Sintase Quinase 3 beta/metabolismo , Células-Tronco Neurais/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Tri-Iodotironina/metabolismo , Humanos , Hidrocarbonetos Halogenados/toxicidade , Células-Tronco Neurais/metabolismo , Células-Tronco Neurais/patologia , Neurogênese/efeitos dos fármacos , Neurogênese/genética
2.
Nat Commun ; 10(1): 2612, 2019 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-31197141

RESUMO

Primary microcephaly is caused by mutations in genes encoding centrosomal proteins including WDR62 and KIF2A. However, mechanisms underlying human microcephaly remain elusive. By creating mutant mice and human cerebral organoids, here we found that WDR62 deletion resulted in a reduction in the size of mouse brains and organoids due to the disruption of neural progenitor cells (NPCs), including outer radial glia (oRG). WDR62 ablation led to retarded cilium disassembly, long cilium, and delayed cell cycle progression leading to decreased proliferation and premature differentiation of NPCs. Mechanistically, WDR62 interacts with and promotes CEP170's localization to the basal body of primary cilium, where CEP170 recruits microtubule-depolymerizing factor KIF2A to disassemble cilium. WDR62 depletion reduced KIF2A's basal body localization, and enhanced KIF2A expression partially rescued deficits in cilium length and NPC proliferation. Thus, modeling microcephaly with cerebral organoids and mice reveals a WDR62-CEP170-KIF2A pathway promoting cilium disassembly, disruption of which contributes to microcephaly.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Cinesina/metabolismo , Microcefalia/patologia , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Fosfoproteínas/metabolismo , Proteínas Repressoras/metabolismo , Animais , Técnicas de Cultura de Células , Proteínas de Ciclo Celular/genética , Diferenciação Celular , Linhagem Celular , Proliferação de Células , Cílios/metabolismo , Modelos Animais de Doenças , Feminino , Técnicas de Inativação de Genes , Humanos , Masculino , Camundongos , Camundongos Knockout , Microcefalia/genética , Proteínas Associadas aos Microtúbulos/genética , Proteínas do Tecido Nervoso/genética , Células-Tronco Neurais/citologia , Células-Tronco Neurais/patologia , Neuroglia/citologia , Neuroglia/patologia , Organoides/patologia , Fosfoproteínas/genética , RNA Interferente Pequeno/metabolismo
3.
Nat Commun ; 10(1): 2000, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-31043608

RESUMO

Capicua (Cic) is a transcriptional repressor mutated in the brain cancer oligodendroglioma. Despite its cancer link, little is known of Cic's function in the brain. We show that nuclear Cic expression is strongest in astrocytes and neurons but weaker in stem cells and oligodendroglial lineage cells. Using a new conditional Cic knockout mouse, we demonstrate that forebrain-specific Cic deletion increases proliferation and self-renewal of neural stem cells. Furthermore, Cic loss biases neural stem cells toward glial lineage selection, expanding the pool of oligodendrocyte precursor cells (OPCs). These proliferation and lineage effects are dependent on de-repression of Ets transcription factors. In patient-derived oligodendroglioma cells, CIC re-expression or ETV5 blockade decreases lineage bias, proliferation, self-renewal, and tumorigenicity. Our results identify Cic as an important regulator of cell fate in neurodevelopment and oligodendroglioma, and suggest that its loss contributes to oligodendroglioma by promoting proliferation and an OPC-like identity via Ets overactivity.


Assuntos
Neoplasias Encefálicas/patologia , Células-Tronco Neurais/patologia , Oligodendroglioma/patologia , Proteínas Proto-Oncogênicas c-ets/metabolismo , Proteínas Repressoras/metabolismo , Animais , Astrócitos/patologia , Diferenciação Celular , Linhagem Celular Tumoral , Proliferação de Células , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Embrião de Mamíferos , Feminino , Técnicas de Silenciamento de Genes , Humanos , Masculino , Camundongos , Camundongos Knockout , Neurônios/patologia , Oligodendroglia/citologia , Oligodendroglia/patologia , Cultura Primária de Células , Prosencéfalo/citologia , Prosencéfalo/patologia , Proteínas Repressoras/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Regulação para Cima , Ensaios Antitumorais Modelo de Xenoenxerto
4.
Nat Med ; 25(5): 784-791, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31061540

RESUMO

Owing to recent medical and technological advances in neonatal care, infants born extremely premature have increased survival rates1,2. After birth, these infants are at high risk of hypoxic episodes because of lung immaturity, hypotension and lack of cerebral-flow regulation, and can develop a severe condition called encephalopathy of prematurity3. Over 80% of infants born before post-conception week 25 have moderate-to-severe long-term neurodevelopmental impairments4. The susceptible cell types in the cerebral cortex and the molecular mechanisms underlying associated gray-matter defects in premature infants remain unknown. Here we used human three-dimensional brain-region-specific organoids to study the effect of oxygen deprivation on corticogenesis. We identified specific defects in intermediate progenitors, a cortical cell type associated with the expansion of the human cerebral cortex, and showed that these are related to the unfolded protein response and changes. Moreover, we verified these findings in human primary cortical tissue and demonstrated that a small-molecule modulator of the unfolded protein response pathway can prevent the reduction in intermediate progenitors following hypoxia. We anticipate that this human cellular platform will be valuable for studying the environmental and genetic factors underlying injury in the developing human brain.


Assuntos
Lesões Encefálicas/etiologia , Hipóxia Encefálica/etiologia , Modelos Neurológicos , Lesões Encefálicas/metabolismo , Lesões Encefálicas/patologia , Hipóxia Celular/genética , Hipóxia Celular/fisiologia , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Humanos , Hipóxia Encefálica/metabolismo , Hipóxia Encefálica/patologia , Lactente Extremamente Prematuro , Recém-Nascido , Células-Tronco Neurais/metabolismo , Células-Tronco Neurais/patologia , Neurogênese/genética , Neurogênese/fisiologia , Organoides/metabolismo , Organoides/patologia , Proteínas com Domínio T/metabolismo , Resposta a Proteínas não Dobradas
5.
Proc Natl Acad Sci U S A ; 116(15): 7483-7492, 2019 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-30923117

RESUMO

Three-dimensional cell cultures are leading the way to the fabrication of tissue-like constructs useful to developmental biology and pharmaceutical screenings. However, their reproducibility and translational potential have been limited by biomaterial and culture media compositions, as well as cellular sources. We developed a construct comprising synthetic multifunctionalized hydrogels, serum-free media, and densely seeded good manufacturing practice protocol-grade human neural stem cells (hNSC). We tracked hNSC proliferation, differentiation, and maturation into GABAergic, glutamatergic, and cholinergic neurons, showing entangled electrically active neural networks. The neuroregenerative potential of the "engineered tissue" was assessed in spinal cord injuries, where hNSC-derived progenitors and predifferentiated hNSC progeny, embedded in multifunctionalized hydrogels, were implanted. All implants decreased astrogliosis and lowered the immune response, but scaffolds with predifferentiated hNSCs showed higher percentages of neuronal markers, better hNSC engraftment, and improved behavioral recovery. Our hNSC-construct enables the formation of 3D functional neuronal networks in vitro, allowing novel strategies for hNSC therapies in vivo.


Assuntos
Diferenciação Celular , Proliferação de Células , Células Imobilizadas , Hidrogéis , Células-Tronco Neurais , Regeneração , Traumatismos da Medula Espinal , Animais , Células Imobilizadas/metabolismo , Células Imobilizadas/patologia , Células Imobilizadas/transplante , Neurônios Colinérgicos/metabolismo , Neurônios Colinérgicos/patologia , Modelos Animais de Doenças , Feminino , Xenoenxertos , Humanos , Hidrogéis/química , Hidrogéis/farmacologia , Células-Tronco Neurais/metabolismo , Células-Tronco Neurais/patologia , Células-Tronco Neurais/transplante , Ratos , Ratos Sprague-Dawley , Traumatismos da Medula Espinal/metabolismo , Traumatismos da Medula Espinal/patologia , Traumatismos da Medula Espinal/terapia
6.
Neurosci Lett ; 703: 162-167, 2019 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-30902571

RESUMO

Prader-Willi syndrome (PWS) is a neurodevelopmental disorder caused by a lack of expression of paternally inherited genes located in the15q11.2-q13 chromosome region. An obstacle in the study of human neurological diseases is the inaccessibility of brain material. Generation of induced pluripotent stem cells (iPSC cells) from patients can partially overcome this problem. We characterized the cellular differentiation potential of iPS cells derived from a PWS patient with a paternal 15q11-q13 deletion. A gene tip transcriptome array revealed very low expression of genes in the 15q11.2-q13 chromosome region, including SNRPN, SNORD64, SNORD108, SNORD109, and SNORD116, in iPS cells of this patient compared to that in control iPS cells. Methylation-specific PCR analysis of the SNRPN gene locus indicated that the PWS region of the paternal chromosome was deleted or methylated in iPS cells from the patient. Both the control and patient-derived iPS cells were positive for Oct3/4, a key marker of pluripotent cells. After 11 days of differentiation into neural stem cells (NSCs), Oct3/4 expression in both types of iPS cells was decreased. The NSC markers Pax6, Sox1, and Nestin were induced in NSCs derived from control iPS cells, whereas induction of these NSC markers was not apparent in NSCs derived from iPS cells from the patient. After 7 days of differentiation into neurons, neuronal cells derived from control iPS cells were positive for ßIII-tubulin and MAP2. However, neuronal cells derived from patient iPS cells only included a few immunopositive neurons. The mRNA expression levels of the neuronal marker ßIII-tubulin were increased in neuronal cells derived from control iPS cells, while the expression levels of ßIII-tubulin in neuronal cells derived from patient iPS cells were similar to those of NSCs. These results indicate that iPS cells derived from a PWS patient exhibited neuronal differentiation defects.


Assuntos
Células-Tronco Pluripotentes Induzidas/patologia , Neurônios/patologia , Síndrome de Prader-Willi/patologia , Diferenciação Celular , Cromossomos Humanos Par 15/genética , Humanos , Células-Tronco Neurais/patologia , Síndrome de Prader-Willi/genética
7.
Neurosci Lett ; 703: 139-144, 2019 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-30904575

RESUMO

Brain tissue undergoes substantial activity-dependent reorganisation after stroke due to neuronal plasticity, leading to partial functional recovery in patients. Concurrent myelin repair is crucial for proper neuronal network function and reorganisation. Myelin repair after stroke might occur as myelin plasticity or as remyelination through the recruitment and differentiation of oligodendrocyte precursor cells (OPCs), which become myelin-forming oligodendrocytes (OLs). These two processes might share a similar guiding mechanism, which is postulated to depend on neuronal activity and glutamate signaling to OPCs. However, with ageing, the ability of OPCs to differentiate into myelinating OLs decreases due to changes in their ion channel and neurotransmitter receptor expression profile, rendering them less sensitive to neuronal activity. Because of their unique ability to replace damaged OLs, OPCs represent a potential therapeutic target for myelin repair in the context of stroke.


Assuntos
Bainha de Mielina/fisiologia , Neurônios/fisiologia , Acidente Vascular Cerebral/patologia , Animais , Diferenciação Celular , Proliferação de Células , Humanos , Células-Tronco Neurais/patologia , Plasticidade Neuronal , Oligodendroglia/patologia , Acidente Vascular Cerebral/fisiopatologia
8.
Neurosci Lett ; 703: 111-118, 2019 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-30904577

RESUMO

Alzheimer's disease (AD) is a progressive, degenerative disorder that mainly results in memory loss and a cognitive disorder. Although the cause of AD is still unknown, a minor percentage of AD cases are produced by genetic mutations in the presenilin-1 (PSEN1) gene. Differentiated neuronal cells derived from induced pluripotent stem cells (iPSCs) of patients can recapitulate key pathological features of AD in vitro; however, iPSCs studies focused on the p.E280 A mutation, which afflicts the largest family in the world with familial AD, have not been carried out yet. Although a link between the loss of the Y (LOY) chromosome in peripheral blood cells and risk for AD has been reported, LOY-associated phenotype has not been previously studied in PSEN1 E280 A carriers. Here, we report the reprogramming of fibroblast cells into iPSCs from a familial AD patient with the PSEN1 E280 A mutation, followed by neuronal differentiation into neural precursor cells (NPCs), and the differentiation of NPCs into differentiated neurons that lacked a Y chromosome. Although the PSEN1 E280 A iPSCs and NPCs were successfully obtained, after 8 days of differentiation, PSEN1 E280 A differentiated neurons massively died reflected by release and/ or activation of death markers, and failed to reach complete neural differentiation compared to PSEN 1 wild type cells.


Assuntos
Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Cromossomos Humanos Y , Células-Tronco Pluripotentes Induzidas/metabolismo , Fragmentos de Peptídeos/metabolismo , Presenilina-1/genética , Doença de Alzheimer/genética , Morte Celular , Diferenciação Celular , Reprogramação Celular , Espaço Extracelular/metabolismo , Fibroblastos/metabolismo , Fibroblastos/patologia , Humanos , Células-Tronco Pluripotentes Induzidas/patologia , Mutação , Células-Tronco Neurais/patologia , Neurônios/patologia
9.
Transl Res ; 210: 57-79, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30904442

RESUMO

Radial glial cells (RGCs) are the neural stem/progenitor cells (NSPCs) that give rise to most of neurons and glial cells that constitute the adult central nervous system. A hallmark of RGCs is their polarization along the apical-basal axis. They extend a long basal process that contacts the pial surface and a short apical process to the ventricular surface. Adherens junctions (AJs) are organized as belt-like structures at the most-apical lateral plasma membrane of the apical processes. These junctional complexes anchor RGCs to each other and allow the recruitment of cytoplasmic proteins that act as apical-basal determinants. It has been proposed that disruption of AJs underlies the onset of different neurodevelopmental disorders. In fact, studies performed in different animal models indicate that loss of function of AJs-related proteins in NSPCs can disrupt cell polarity, imbalance proliferation and/or differentiation rates and increase cell death, which, in turn, lead to disruption of the cytoarchitecture of the ventricular zone, protrusion of non-polarized cells into the ventricles, cortical thinning, and ventriculomegaly/hydrocephalus, among other neuropathological findings. Recent Zika virus (ZIKV) outbreaks and the high comorbidity of ZIKV infection with congenital neurodevelopmental defects have led to the World Health Organization to declare a public emergency of international concern. Thus, noteworthy advances have been made in clinical and experimental ZIKV research. This review summarizes the current knowledge regarding the function of AJs in normal and pathological corticogenesis and focuses on the neuropathological and cellular mechanisms involved in congenital ZIKV syndrome, highlighting the potential role of cell-to-cell junctions between NSPCs in the etiopathogenesis of such syndrome.


Assuntos
Junções Aderentes/metabolismo , Polaridade Celular , Células-Tronco Neurais/patologia , Transtornos do Neurodesenvolvimento/patologia , Transtornos do Neurodesenvolvimento/virologia , Infecção por Zika virus/congênito , Animais , Humanos , Transtornos do Neurodesenvolvimento/epidemiologia , Síndrome
10.
Stem Cell Res ; 35: 101390, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30763736

RESUMO

Notch signalling regulates neural stem cell (NSC) proliferation, differentiation and survival for the correct development and functioning of the central nervous system. Overactive Notch2 signalling has been associated with poor prognosis of aggressive brain tumours, such as glioblastoma multiforme (GBM). We recently reported that constitutive expression of the Notch2 intracellular domain (N2ICD) enhances proliferation and gliogenesis in NSCs. Here, we investigated the mechanism by which Notch2 promotes resistance to apoptosis of NSCs to cytotoxic insults. We performed ex vivo studies using NSC cultures from transgenic mice constitutively expressing N2ICD. These NSCs expressed increased levels of pro-survival factors and lack an apoptotic response to the topoisomerase inhibitor etoposide, not showing neither mitochondrial damage nor caspase activation. Interestingly, Notch2 signalling also regulated chemoresistance of human GBM cells to etoposide. We also identified a signalling crosstalk with FGF signalling pathway involved in this resistance to apoptosis of NSCs. Aberrant Notch2 expression enhances fibroblast growth factor receptor-1 (FGFR1) activity to specifically target the AKT-GSK3 signalling pathway to block apoptosis. These results have implications for understanding molecular changes involved in both tumorigenesis and therapy resistance.


Assuntos
Neoplasias Encefálicas/metabolismo , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Etoposídeo/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glioblastoma/metabolismo , Células-Tronco Neurais/metabolismo , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/biossíntese , Receptor Notch2/metabolismo , Transdução de Sinais/efeitos dos fármacos , Ativação Transcricional/efeitos dos fármacos , Animais , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/genética , Glioblastoma/genética , Glioblastoma/patologia , Humanos , Camundongos Transgênicos , Células-Tronco Neurais/patologia , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/genética , Receptor Notch2/genética , Transdução de Sinais/genética
11.
Neurochem Res ; 44(4): 905-916, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30690681

RESUMO

Neuroinflammation is an important part of the development of neurodegenerative diseases such as Alzheimer's disease (AD), Parkinson's and amyotrophic lateral sclerosis. Inflammatory factors destroy the balance of the microenvironment, which results in changes in neural stem cell differentiation and proliferation behaviour. However, the mechanism underlying inflammatory factor-induced NSC behavioural changes is not clear. Resistin is a proinflammatory and adipogenic factor and is involved in several human pathology processes. The neural stem cell microenvironment changes when the concentration of resistin in the brain during an inflammatory response disease increases. In the present study, we explored the effect and mechanism of resistin on the proliferation and differentiation of neural stem cells. We found that intracerebroventricular injection of resistin induced a decrease in GFAP-positive cells in mice by influencing NSC differentiation. Resistin significantly decreased TEER and increased permeability in an in vitro blood-brain barrier model, which is consistent with the results of an HBMEC-astrocyte coculture system. Resistin-inhibited astrocyte differentiation is mediated through TLR4 on neural stem cells. To our knowledge, this is the first study reporting the effect of resistin on neural stem cells. Our findings shed light on resistin-involved neural stem cell degeneration mechanisms.


Assuntos
Astrócitos/metabolismo , Barreira Hematoencefálica/metabolismo , Permeabilidade Capilar/fisiologia , Diferenciação Celular/fisiologia , Células-Tronco Neurais/metabolismo , Resistina/administração & dosagem , Animais , Astrócitos/efeitos dos fármacos , Astrócitos/patologia , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/patologia , Permeabilidade Capilar/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Endotélio Vascular/patologia , Humanos , Injeções Intraventriculares , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Células-Tronco Neurais/efeitos dos fármacos , Células-Tronco Neurais/patologia , Neurogênese/efeitos dos fármacos , Neurogênese/fisiologia , Resistina/toxicidade
12.
Neurosci Bull ; 35(2): 216-224, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30607770

RESUMO

Diffuse intrinsic pontine glioma (DIPG) is the main cause of brain tumor-related death among children. Until now, there is still a lack of effective therapy with prolonged overall survival for this disease. A typical strategy for preclinical cancer research is to find out the molecular differences between tumor tissue and para-tumor normal tissue, in order to identify potential therapeutic targets. Unfortunately, it is impossible to obtain normal tissue for DIPG because of the vital functions of the pons. Here we report the human fetal hindbrain-derived neural progenitor cells (pontine progenitor cells, PPCs) as normal control cells for DIPG. The PPCs not only harbored similar cell biological and molecular signatures as DIPG glioma stem cells, but also had the potential to be immortalized by the DIPG-specific mutation H3K27M in vitro. These findings provide researchers with a candidate normal control and a potential medicine carrier for preclinical research on DIPG.


Assuntos
Neoplasias do Tronco Encefálico/metabolismo , Glioma/metabolismo , Células-Tronco Neurais/metabolismo , Ponte/metabolismo , Animais , Neoplasias do Tronco Encefálico/genética , Neoplasias do Tronco Encefálico/patologia , Linhagem Celular Tumoral , Senescência Celular , Feminino , Glioma/genética , Glioma/patologia , Histonas/genética , Humanos , Camundongos Endogâmicos NOD , Camundongos SCID , Transplante de Neoplasias , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Células-Tronco Neurais/efeitos dos fármacos , Células-Tronco Neurais/patologia , Ponte/embriologia , Ponte/patologia , Cultura Primária de Células
13.
Bull Exp Biol Med ; 166(3): 317-320, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30627909

RESUMO

The in vitro and in vivo models of ethanol-induced neurodegeneration were used to evaluate the content and functional activity of various types of regeneration-competent cells in subventricular zone of the cerebral hemispheres in C57Bl/6JY mice. In nervous tissue culture, ethanol (65 mM) produced no effect on formation of neurospheres. When administered per os in a daily dose of 3 g/kg for 8 weeks, ethanol produced no effect on the number of neural CFU in situ. In both cases, ethanol reduced proliferative activity of neural CFU. Long-term administration of ethanol in vivo suppressed differentiation of neural stem cells and decreased the number of committed precursors (neural cluster-forming units) in the subventricular zone of cerebral hemispheres. In vitro application of ethanol stimulated secretion of humoral growth factors by the cluster-forming neural glial cells. In contrast, in vivo administration of ethanol suppressed this secretion.


Assuntos
Alcoolismo/patologia , Cérebro/efeitos dos fármacos , Etanol/farmacologia , Ventrículos Laterais/efeitos dos fármacos , Doenças Neurodegenerativas/patologia , Neurônios/efeitos dos fármacos , Alcoolismo/metabolismo , Animais , Contagem de Células , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Cérebro/metabolismo , Cérebro/patologia , Cérebro/fisiopatologia , Modelos Animais de Doenças , Peptídeos e Proteínas de Sinalização Intercelular/agonistas , Peptídeos e Proteínas de Sinalização Intercelular/biossíntese , Ventrículos Laterais/metabolismo , Ventrículos Laterais/patologia , Ventrículos Laterais/fisiopatologia , Camundongos , Camundongos Endogâmicos C57BL , Células-Tronco Neurais/efeitos dos fármacos , Células-Tronco Neurais/patologia , Doenças Neurodegenerativas/metabolismo , Neuroglia/efeitos dos fármacos , Neuroglia/metabolismo , Neuroglia/patologia , Neurônios/patologia , Cultura Primária de Células , Esferoides Celulares/efeitos dos fármacos
14.
Environ Toxicol ; 34(4): 548-555, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30698896

RESUMO

OBJECTIVE: To investigate the effect of paraquat (PQ) exposure on gene expression in neural stem cells as well as structures and functions of vascular endothelial cells. METHODS: RNA-Seq was used to explore the differentially expressed genes in human umbilical cord blood-neural stem cells (HUCB-NSCs) at different stages (eg, proliferation, early and late differentiation) in the presence of PQ. The effects of PQ on human umbilical vein endothelial cells (HUVECs), including cell proliferation, apoptosis, cytokines secretion, and expression of tight junction proteins, were assessed with CCK-8, flow cytometry, ELISA, and western blot analysis, individually. RESULTS: A total of 53 genes were up-regulated and 61 genes were down-regulated in PQ treated HUCB-NSCs, including seven genes associated with the differentiation of neural stem cells, for example, Gfap, S100B, Oct4, Gdf3, Sox1, Pax6, and Ngn1. PQ treatment significantly reduced the proliferation of HUVECs, inhibited cytokines secretion (VEGF, BFGF) and expressions of tight junction-associated protein (Claudin 1, Occludin, ZO-1), as well as induced significant apoptosis. CONCLUSION: Our study suggests that PQ impairs the development of nervous system by regulating the expression of genes associated with neural stem cell differentiation, as well as the structure and function of vascular endothelial cells, which together lead to abnormality in the nervous system.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células-Tronco Neurais/efeitos dos fármacos , Paraquat/toxicidade , Apoptose/efeitos dos fármacos , Apoptose/genética , Diferenciação Celular/genética , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Regulação para Baixo , Sequenciamento de Nucleotídeos em Larga Escala , Células Endoteliais da Veia Umbilical Humana/patologia , Humanos , Células-Tronco Neurais/patologia , Proteínas de Junções Íntimas/genética , Regulação para Cima
15.
Mult Scler Relat Disord ; 28: 263-272, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30639828

RESUMO

Sox2 transcription factor has been frequently used for reprograming starting cells to neural progenitor/stem cells. In vivo administration of Sox2 in the adult mouse brain reprogrammed the transduced astrocytes to neurons. In searching for adequate cell source for repairing the myelin insults, here, we studied the possible conversion of astrocytes to oligodendrocyte lineage cells by Sox2, while an extensive demyelination exists in animal brain. Lentiviral particles expressing Sox2-GFP were injected into the corpora callosa of animals fed with cuprizone diet for 12 weeks. Transduced cells were mainly astrocytes that changed their fate to oligodendrocyte lineage cells by time. For further conformation astrocytes received the vector in culture and then transplanted to the animal brains. Tracing the fate of transplanted cells showed their conversion to oligodendrocyte lineage cells. In vitro transduced cell were also maintained in the oligodendrocyte progenitor cell (OPC) induction medium. Produced OPC-like cells were positive for specific markers. This study provides a new strategy for endogenous production of myelinating cells. After optimizing the experimental conditions for safety and feasibility, this approach may contribute into future cell based therapies in patients with white matter insults as like as those with multiple sclerosis.


Assuntos
Astrócitos/metabolismo , Encéfalo/metabolismo , Linhagem da Célula/fisiologia , Doenças Desmielinizantes/metabolismo , Oligodendroglia/metabolismo , Fatores de Transcrição SOXB1/metabolismo , Animais , Astrócitos/patologia , Astrócitos/transplante , Encéfalo/patologia , Diferenciação Celular/fisiologia , Células Cultivadas , Cuprizona , Doenças Desmielinizantes/patologia , Doenças Desmielinizantes/terapia , Modelos Animais de Doenças , Vetores Genéticos , Lentivirus/genética , Masculino , Camundongos Endogâmicos C57BL , Células-Tronco Neurais/metabolismo , Células-Tronco Neurais/patologia , Células-Tronco Neurais/transplante , Oligodendroglia/patologia , Oligodendroglia/transplante , Regeneração/fisiologia , Fatores de Transcrição SOXB1/genética
16.
Nat Neurosci ; 22(2): 243-255, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30617258

RESUMO

Autism spectrum disorder (ASD) is thought to emerge during early cortical development. However, the exact developmental stages and associated molecular networks that prime disease propensity are elusive. To profile early neurodevelopmental alterations in ASD with macrocephaly, we monitored subject-derived induced pluripotent stem cells (iPSCs) throughout the recapitulation of cortical development. Our analysis revealed ASD-associated changes in the maturational sequence of early neuron development, involving temporal dysregulation of specific gene networks and morphological growth acceleration. The observed changes tracked back to a pathologically primed stage in neural stem cells (NSCs), reflected by altered chromatin accessibility. Concerted over-representation of network factors in control NSCs was sufficient to trigger ASD-like features, and circumventing the NSC stage by direct conversion of ASD iPSCs into induced neurons abolished ASD-associated phenotypes. Our findings identify heterochronic dynamics of a gene network that, while established earlier in development, contributes to subsequent neurodevelopmental aberrations in ASD.


Assuntos
Transtorno do Espectro Autista/genética , Redes Reguladoras de Genes , Potenciais Pós-Sinápticos Inibidores/fisiologia , Rede Nervosa/fisiopatologia , Neurônios/fisiologia , Transtorno do Espectro Autista/patologia , Transtorno do Espectro Autista/fisiopatologia , Humanos , Células-Tronco Pluripotentes Induzidas/patologia , Células-Tronco Neurais/patologia , Neurônios/patologia
17.
Methods Mol Biol ; 1869: 1-9, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30324509

RESUMO

From stem cells, to the cancer stem cell hypothesis and intratumoral heterogeneity, the following introductory chapter on brain tumor stem cells explores the history of normal and cancerous stem cells, and their implication in the current model of brain tumor development. The origins of stem cells date back to the 1960s, when they were first described as cells capable of self-renewal, extensive proliferation, and differentiation. Since then, many advances have been made and adult stem cells are now known to be present in a very wide variety of tissues. Neural stem cells were subsequently discovered 30 years later, which was shortly followed by the discovery of cancer stem cells in leukemia and in brain tumors over the next decade, effectively enabling a new understanding of cancer. Since then, many markers including CD133, brain cancer stem cells have been implicated in a variety of phenomena including intratumoral heterogeneity on the genomic, cellular, and functional levels, tumor initiation, chemotherapy-resistance, radiation-resistance, and are believed to be ultimately responsible for tumor relapse. Understanding this small and rare population of cells could be the key to solving the great enigma that is cancer.


Assuntos
Neoplasias Encefálicas/patologia , Células-Tronco Neoplásicas/patologia , Animais , Humanos , Células-Tronco Neurais/patologia
18.
Methods Mol Biol ; 1869: 127-142, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30324520

RESUMO

Utilization of human embryonic stem cells (hESCs) as a model system to study highly malignant pediatric cancers has led to significant insight into the molecular mechanisms governing tumor progression and has revealed novel therapeutic targets for these devastating diseases. Here, we describe a method for generating heterogeneous populations of neural precursors from both normal and neoplastic hESCs and the subsequent injection of neoplastic human embryonic neural cells (hENs) into intracerebellar or intracranial xenograft models. Histopathologically, neural tumors derived from neoplastic hENs exhibit features similar to more aggressive medulloblastoma, the most common malignant primary pediatric brain tumor. In this chapter, we will outline the detailed methods for culturing normal and neoplastic neural precursor cells in both adherent and tumorsphere format and the full characterization of the brain tumors generated from these cells in non-obese diabetic severe combined immunodeficiency (NOD SCID) mice.


Assuntos
Neoplasias Encefálicas/patologia , Células-Tronco Embrionárias Humanas/patologia , Modelos Biológicos , Animais , Bovinos , Ensaios de Migração Celular , Humanos , Lentivirus/metabolismo , Camundongos , Células-Tronco Neurais/patologia , Células-Tronco Neurais/transplante , Perfusão , Esferoides Celulares/patologia , Fixação de Tecidos , Transdução Genética
19.
Exp Neurol ; 311: 274-284, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30359565

RESUMO

BACKGROUND: Subarachnoid hemorrhage (SAH) is a devastating cerebrovascular disease that leads to poor outcomes. Neurogenesis, an essential recovery mechanism after brain injury, has not been fully elucidated after SAH. METHODS: A total of 122 SD rats were used in this study. For experiment one, the rats were randomly divided into six groups: sham and SAH with different time points (1,3,5,7,14 days) (n = 12/group). An endovascular perforation method was conducted for SAH model. Rats were injected with 5-Bromo-2'-deoxyuridine (BrdU, 50 mg/kg) 24 h before euthanasia at different time points after SAH. The BrdU labeled cells were detected by immunohistochemistry; Doublecortin (DCX) and glial fibrillary acidic protein (GFAP) were measured by western blot and immunohistochemistry. For experiment two, rats were randomly divided into five groups: sham and SAH with different time points (1, 2, 4, 8 weeks) (n = 6/group). Rats received BrdU (50 mg/kg) once daily for 7 days after the induction of SAH. Double immunofluorescence staining was used to verify proliferation, differentiation and migration of progenitor cells. Rotarod test and water maze used to test the neurobehavioral recovery. RESULTS: Our results showed that BrdU positive cells in hippocampus changed overtime after SAH. BrdU positive cells decreased as early as 1 day reaching lowest levels at 3 days after SAH, after which it gradually recovered. Similar change patterns were observed with DCX, which was reversed with GFAP. In addition, BrdU did not co-localize with cleaved caspase-3. The BrdU positive cells mainly differentiated into immature neurons for short-term fate, whereas they differentiated into mature neurons for long-term fate but not astrocytes, which facilitated neurobehavioral recovery after SAH. CONCLUSION: Neurogenesis in the hippocampus changes overtime after SAH. The neuronal progenitor cells may play an essential role in the neurobehavioral recovery after brain injury induced by SAH, since short-term progenitors helped with the recovery of immature neurons in the hippocampus, whereas long-term progenitors differentiated into mature neurons.


Assuntos
Hipocampo/metabolismo , Hipocampo/patologia , Células-Tronco Neurais/metabolismo , Neurogênese/fisiologia , Hemorragia Subaracnóidea/metabolismo , Hemorragia Subaracnóidea/patologia , Animais , Bromodesoxiuridina/metabolismo , Masculino , Células-Tronco Neurais/patologia , Ratos , Ratos Sprague-Dawley , Células-Tronco/metabolismo , Células-Tronco/patologia , Fatores de Tempo
20.
Mol Cell ; 73(5): 1001-1014.e8, 2019 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-30527540

RESUMO

In Parkinson's disease (PD), α-synuclein (αS) pathologically impacts the brain, a highly lipid-rich organ. We investigated how alterations in αS or lipid/fatty acid homeostasis affect each other. Lipidomic profiling of human αS-expressing yeast revealed increases in oleic acid (OA, 18:1), diglycerides, and triglycerides. These findings were recapitulated in rodent and human neuronal models of αS dyshomeostasis (overexpression; patient-derived triplication or E46K mutation; E46K mice). Preventing lipid droplet formation or augmenting OA increased αS yeast toxicity; suppressing the OA-generating enzyme stearoyl-CoA-desaturase (SCD) was protective. Genetic or pharmacological SCD inhibition ameliorated toxicity in αS-overexpressing rat neurons. In a C. elegans model, SCD knockout prevented αS-induced dopaminergic degeneration. Conversely, we observed detrimental effects of OA on αS homeostasis: in human neural cells, excess OA caused αS inclusion formation, which was reversed by SCD inhibition. Thus, monounsaturated fatty acid metabolism is pivotal for αS-induced neurotoxicity, and inhibiting SCD represents a novel PD therapeutic approach.


Assuntos
Antiparkinsonianos/farmacologia , Descoberta de Drogas/métodos , Inibidores Enzimáticos/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Metabolômica/métodos , Neurônios/efeitos dos fármacos , Doença de Parkinson/tratamento farmacológico , Estearoil-CoA Dessaturase/antagonistas & inibidores , alfa-Sinucleína/toxicidade , Animais , Caenorhabditis elegans/efeitos dos fármacos , Caenorhabditis elegans/enzimologia , Caenorhabditis elegans/genética , Linhagem Celular , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/enzimologia , Córtex Cerebral/patologia , Diglicerídeos/metabolismo , Modelos Animais de Doenças , Neurônios Dopaminérgicos/efeitos dos fármacos , Neurônios Dopaminérgicos/enzimologia , Neurônios Dopaminérgicos/patologia , Humanos , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Células-Tronco Pluripotentes Induzidas/enzimologia , Células-Tronco Pluripotentes Induzidas/patologia , Gotículas Lipídicas/efeitos dos fármacos , Gotículas Lipídicas/enzimologia , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Terapia de Alvo Molecular , Degeneração Neural , Células-Tronco Neurais/efeitos dos fármacos , Células-Tronco Neurais/enzimologia , Células-Tronco Neurais/patologia , Neurônios/enzimologia , Neurônios/patologia , Ácido Oleico/metabolismo , Doença de Parkinson/enzimologia , Doença de Parkinson/genética , Doença de Parkinson/patologia , Ratos Sprague-Dawley , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/enzimologia , Saccharomyces cerevisiae/genética , Estearoil-CoA Dessaturase/metabolismo , Triglicerídeos/metabolismo , alfa-Sinucleína/genética
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