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1.
Toxicol Lett ; 349: 69-83, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34126181

RESUMO

Exposure to sterigmatocystin (STC) raises concerns on developmental neurological disorders. The present study investigated the effects of maternal oral STC exposure on postnatal hippocampal neurogenesis of offspring in rats. Dams were exposed to STC (1.7, 5.0, and 15.0 ppm in diet) from gestational day 6 until day 21 post-delivery (weaning), and offspring were maintained without STC exposure until adulthood on postnatal day (PND) 77, in accordance with OECD chemical testing guideline Test No. 426. On PND 21, 15.0-ppm STC decreased type-3 neural progenitor cell numbers in the subgranular zone (SGZ) due to suppressed proliferation. Increased γ-H2AX-immunoreactive (+) cell numbers in the SGZ and Ercc1 upregulation and Brip1 downregulation in the dentate gyrus suggested induction of DNA double-strand breaks in SGZ cells. Upregulation of Apex1 and Ogg1 and downregulation of antioxidant genes downstream of NRF2-Keap1 signaling suggested induction of oxidative DNA damage. Increased p21WAF1/CIP1+ SGZ cell numbers and suppressed cholinergic signaling through CHRNB2-containing receptors in GABAergic interneurons suggested potential neurogenesis suppression mechanisms. Multiple mechanisms involving N-methyl-d-aspartate (NMDA) receptor-mediated glutamatergic signaling and various GABAergic interneuron subpopulations, including CHRNA7-expressing somatostatin+ interneurons activated by BDNF-TrkB signaling, may be involved in ameliorating the neurogenesis. Upregulation of Arc, Ptgs2, and genes encoding NMDA receptors and α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors suggested synaptic plasticity facilitation. On PND 77, ARC+ granule cells decreased, and Nos2 was upregulated following 15.0 ppm STC exposure, suggesting oxidative stress-mediated synaptic plasticity suppression. Inverse pattern in gene expression changes in vesicular glutamate transporter isoforms, Slc17a7 and Slc17a6, from weaning might also be responsible for the synaptic plasticity suppression. The no-observed-adverse-effect level of maternal oral STC exposure for offspring neurogenesis was determined to be 5.0 ppm, translating to 0.34-0.85 mg/kg body weight/day.


Assuntos
Proliferação de Células/efeitos dos fármacos , Giro Denteado/efeitos dos fármacos , Células-Tronco Neurais/efeitos dos fármacos , Neurogênese/efeitos dos fármacos , Plasticidade Neuronal/efeitos dos fármacos , Esterigmatocistina/toxicidade , Animais , Apoptose/efeitos dos fármacos , Quebras de DNA de Cadeia Dupla , Giro Denteado/metabolismo , Giro Denteado/patologia , Relação Dose-Resposta a Droga , Regulação da Expressão Gênica , Células-Tronco Neurais/metabolismo , Células-Tronco Neurais/patologia , Nível de Efeito Adverso não Observado , Estresse Oxidativo/efeitos dos fármacos , Ratos Sprague-Dawley , Receptores de Neurotransmissores/genética , Receptores de Neurotransmissores/metabolismo , Desmame
2.
Int J Mol Sci ; 22(11)2021 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-34074027

RESUMO

The development of a biomimetic neuronal network from neural cells is a big challenge for researchers. Recent advances in nanotechnology, on the other hand, have enabled unprecedented tools and techniques for guiding and directing neural stem cell proliferation and differentiation in vitro to construct an in vivo-like neuronal network. Nanotechnology allows control over neural stem cells by means of scaffolds that guide neurons to reform synaptic networks in suitable directions in 3D architecture, surface modification/nanopatterning to decide cell fate and stimulate/record signals from neurons to find out the relationships between neuronal circuit connectivity and their pathophysiological functions. Overall, nanotechnology-mediated methods facilitate precise physiochemical controls essential to develop tools appropriate for applications in neuroscience. This review emphasizes the newest applications of nanotechnology for examining central nervous system (CNS) roles and, therefore, provides an insight into how these technologies can be tested in vitro before being used in preclinical and clinical research and their potential role in regenerative medicine and tissue engineering.


Assuntos
Técnicas de Cultura de Células/métodos , Nanotecnologia/métodos , Rede Nervosa/metabolismo , Células-Tronco Neurais/metabolismo , Neurogênese , Engenharia Tecidual/métodos , Animais , Técnicas de Cultura de Células/instrumentação , Humanos , Nanotecnologia/instrumentação , Rede Nervosa/ultraestrutura , Células-Tronco Neurais/ultraestrutura , Neurogênese/fisiologia , Medicina Regenerativa , Engenharia Tecidual/instrumentação
3.
Cell Prolif ; 54(7): e13027, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33988263

RESUMO

OBJECTIVES: The area of the subventricular zone (SVZ) in the adult brain exhibits the highest number of proliferative cells, which, together with the olfactory bulb (OB), maintains constant brain plasticity through the generation, migration and integration of newly born neurons. Despite Tau and its malfunction is increasingly related to deficits of adult hippocampal neurogenesis and brain plasticity under pathological conditions [e.g. in Alzheimer's disease (AD)], it remains unknown whether Tau plays a role in the neurogenic process of the SVZ and OB system under conditions of chronic stress, a well-known sculptor of brain and risk factor for AD. MATERIALS AND METHODS: Different types of newly born cells in SVZ and OB were analysed in animals that lack Tau gene (Tau-KO) and their wild-type littermates (WT) under control or chronic stress conditions. RESULTS: We demonstrate that chronic stress reduced the number of proliferating cells and neuroblasts in the SVZ leading to decreased number of newborn neurons in the OB of adult WT, but not Tau-KO, mice. Interestingly, while stress-evoked changes were not detected in OB granular cell layer, Tau-KO exhibited increased number of mature neurons in this layer indicating altered neuronal migration due to Tau loss. CONCLUSIONS: Our findings suggest the critical involvement of Tau in the neurogenesis suppression of SVZ and OB neurogenic niche under stressful conditions highlighting the role of Tau protein as an essential regulator of stress-driven plasticity deficits.


Assuntos
Ventrículos Laterais/metabolismo , Bulbo Olfatório/metabolismo , Estresse Fisiológico , Proteínas tau/metabolismo , Animais , Comportamento Animal , Proliferação de Células , Sobrevivência Celular , Ventrículos Laterais/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Células-Tronco Neurais/citologia , Células-Tronco Neurais/metabolismo , Neurogênese , Bulbo Olfatório/patologia , Oligodendroglia/citologia , Oligodendroglia/metabolismo , Proteínas tau/genética
4.
J Affect Disord ; 290: 61-64, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-33993081

RESUMO

BACKGROUND: Brain-derived neurotrophic factor (BDNF) antisense RNA (BDNF-AS) was identified as naturally conserved non-coding antisense RNA that suppresses the transcription of BDNF. METHODS: We measured the expression of BDNF mRNA and BDNF-AS mRNA in iPSC and NSC from bipolar disorder (BD) patients and healthy control subjects, and postmortem brain samples such as the corpus callosum, the Brodmann area (BA8), and BA46 from BD patients and age- and sex-matched controls. RESULTS: The expression of BDNF mRNA in iPSC from BD patients (n = 6) was significantly lower than that of control subjects (n = 4) although the expression of BDNF mRNA in NSC from BD patients was significantly higher than that of control subjects. In contrast, there were no changes in the expression of BDNF-AS mRNA in both iPSC and NSC between two groups. The expression of BDNF mRNA in the BA46 from BD patients (n = 35) was significantly lower than that of controls (n = 34) although the expression of BDNF mRNA in the corpus callosum and BA8 was not different between two groups (n = 15). In contrast, there were no changes in expression of BDNF-AS mRNA in the three brain regions between two groups. Interestingly, there were significant positive correlations between BDNF mRNA expression and BDNF-AS mRNA expression in the postmortem brain samples. LIMITATIONS: Sample sizes are relatively low. CONCLUSIONS: Our data suggest that abnormalities in the expression of BDNF, but not BDNF-AS, play a role in the pathogenesis of BD.


Assuntos
Transtorno Bipolar , Células-Tronco Pluripotentes Induzidas , Células-Tronco Neurais , Transtorno Bipolar/genética , Encéfalo/metabolismo , Fator Neurotrófico Derivado do Encéfalo/genética , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Expressão Gênica , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Células-Tronco Neurais/metabolismo
5.
Nat Commun ; 12(1): 2614, 2021 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-33972525

RESUMO

The differentiation of neural stem cells (NSCs) into neurons is proposed to be critical in devising potential cell-based therapeutic strategies for central nervous system (CNS) diseases, however, the determination and prediction of differentiation is complex and not yet clearly established, especially at the early stage. We hypothesize that deep learning could extract minutiae from large-scale datasets, and present a deep neural network model for predictable reliable identification of NSCs fate. Remarkably, using only bright field images without artificial labelling, our model is surprisingly effective at identifying the differentiated cell types, even as early as 1 day of culture. Moreover, our approach showcases superior precision and robustness in designed independent test scenarios involving various inducers, including neurotrophins, hormones, small molecule compounds and even nanoparticles, suggesting excellent generalizability and applicability. We anticipate that our accurate and robust deep learning-based platform for NSCs differentiation identification will accelerate the progress of NSCs applications.


Assuntos
Aprendizado Profundo , Células-Tronco Neurais/citologia , Células-Tronco Neurais/metabolismo , Neurogênese/genética , Animais , Astrócitos/citologia , Astrócitos/metabolismo , Células Cultivadas , Simulação por Computador , Imunofluorescência , Hormônios/farmacologia , Microscopia Eletrônica de Transmissão , Nanopartículas/química , Nanopartículas/ultraestrutura , Fatores de Crescimento Neural/farmacologia , Redes Neurais de Computação , Células-Tronco Neurais/efeitos dos fármacos , Neurônios/citologia , Neurônios/metabolismo , Oligodendroglia/citologia , Oligodendroglia/metabolismo , Ratos
6.
Nat Commun ; 12(1): 2594, 2021 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-33972529

RESUMO

Adult neural stem cells (NSCs) must tightly regulate quiescence and proliferation. Single-cell analysis has suggested a continuum of cell states as NSCs exit quiescence. Here we capture and characterize in vitro primed quiescent NSCs and identify LRIG1 as an important regulator. We show that BMP-4 signaling induces a dormant non-cycling quiescent state (d-qNSCs), whereas combined BMP-4/FGF-2 signaling induces a distinct primed quiescent state poised for cell cycle re-entry. Primed quiescent NSCs (p-qNSCs) are defined by high levels of LRIG1 and CD9, as well as an interferon response signature, and can efficiently engraft into the adult subventricular zone (SVZ) niche. Genetic disruption of Lrig1 in vivo within the SVZ NSCs leads an enhanced proliferation. Mechanistically, LRIG1 primes quiescent NSCs for cell cycle re-entry and EGFR responsiveness by enabling EGFR protein levels to increase but limiting signaling activation. LRIG1 is therefore an important functional regulator of NSC exit from quiescence.


Assuntos
Células-Tronco Adultas/metabolismo , Ventrículos Laterais/metabolismo , Sistema de Sinalização das MAP Quinases/genética , Glicoproteínas de Membrana/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Células-Tronco Neurais/metabolismo , Neurogênese/genética , Células-Tronco Adultas/citologia , Células-Tronco Adultas/efeitos dos fármacos , Animais , Proteína Morfogenética Óssea 4/farmacologia , Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Proliferação de Células/genética , Proteínas de Ligação a DNA/metabolismo , Receptores ErbB/farmacologia , Fator 2 de Crescimento de Fibroblastos/farmacologia , Ontologia Genética , Imuno-Histoquímica , Interferons/farmacologia , Ventrículos Laterais/citologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Glicoproteínas de Membrana/genética , Camundongos , Proteínas do Tecido Nervoso/genética , Células-Tronco Neurais/citologia , Células-Tronco Neurais/efeitos dos fármacos , Proteômica , RNA-Seq , Regeneração/efeitos dos fármacos , Tetraspanina 29/metabolismo , Regulação para Cima
7.
Int J Mol Sci ; 22(9)2021 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-33946340

RESUMO

During brain development, the genome must be repeatedly reconfigured in order to facilitate neuronal and glial differentiation. A host of chromatin remodeling complexes facilitates this process. At the genetic level, the non-redundancy of these complexes suggests that neurodevelopment may require a lexicon of remodelers with different specificities and activities. Here, we focus on the nucleosome remodeling and deacetylase (NuRD) complex. We review NuRD biochemistry, genetics, and functions in neural progenitors and neurons.


Assuntos
Encéfalo/crescimento & desenvolvimento , Montagem e Desmontagem da Cromatina , Complexo Mi-2 de Remodelação de Nucleossomo e Desacetilase/metabolismo , Animais , Encéfalo/embriologia , Encéfalo/metabolismo , Humanos , Complexo Mi-2 de Remodelação de Nucleossomo e Desacetilase/genética , Células-Tronco Neurais/citologia , Células-Tronco Neurais/metabolismo , Neurogênese , Neurônios/citologia , Neurônios/metabolismo
8.
Int J Mol Sci ; 22(9)2021 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-33946667

RESUMO

Transplantation of various types of stem cells as a possible therapy for stroke has been tested for years, and the results are promising. Recent investigations have shown that the administration of the conditioned media obtained after stem cell cultivation can also be effective in the therapy of the central nervous system pathology (hypothesis of their paracrine action). The aim of this study was to evaluate the therapeutic effects of the conditioned medium of hiPSC-derived glial and neuronal progenitor cells in the rat middle cerebral artery occlusion model of the ischemic stroke. Secretory activity of the cultured neuronal and glial progenitor cells was evaluated by proteomic and immunosorbent-based approaches. Therapeutic effects were assessed by overall survival, neurologic deficit and infarct volume dynamics, as well as by the end-point values of the apoptosis- and inflammation-related gene expression levels, the extent of microglia/macrophage infiltration and the numbers of formed blood vessels in the affected area of the brain. As a result, 31% of the protein species discovered in glial progenitor cells-conditioned medium and 45% in neuronal progenitor cells-conditioned medium were cell type specific. The glial progenitor cell-conditioned media showed a higher content of neurotrophins (BDNF, GDNF, CNTF and NGF). We showed that intra-arterial administration of glial progenitor cells-conditioned medium promoted a faster decrease in neurological deficit compared to the control group, reduced microglia/macrophage infiltration, reduced expression of pro-apoptotic gene Bax and pro-inflammatory cytokine gene Tnf, increased expression of anti-inflammatory cytokine genes (Il4, Il10, Il13) and promoted the formation of blood vessels within the damaged area. None of these effects were exerted by the neuronal progenitor cell-conditioned media. The results indicate pronounced cytoprotective, anti-inflammatory and angiogenic properties of soluble factors secreted by glial progenitor cells.


Assuntos
Meios de Cultivo Condicionados/metabolismo , Meios de Cultivo Condicionados/farmacologia , AVC Isquêmico/terapia , Células-Tronco Neurais/citologia , Células-Tronco Neurais/metabolismo , Animais , Células Cultivadas , Modelos Animais de Doenças , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Infarto da Artéria Cerebral Média/metabolismo , Infarto da Artéria Cerebral Média/terapia , Infusões Intra-Arteriais , AVC Isquêmico/metabolismo , AVC Isquêmico/patologia , Masculino , Neuroglia/citologia , Neuroglia/metabolismo , Ratos , Ratos Wistar
9.
Nat Genet ; 53(5): 694-706, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33833454

RESUMO

Characterization of the progression of cellular states during human embryogenesis can provide insights into the origin of pediatric diseases. We examined the transcriptional states of neural crest- and mesoderm-derived lineages differentiating into adrenal glands, kidneys, endothelium and hematopoietic tissue between post-conception weeks 6 and 14 of human development. Our results reveal transitions connecting the intermediate mesoderm and progenitors of organ primordia, the hematopoietic system and endothelial subtypes. Unexpectedly, by using a combination of single-cell transcriptomics and lineage tracing, we found that intra-adrenal sympathoblasts at that stage are directly derived from nerve-associated Schwann cell precursors, similarly to local chromaffin cells, whereas the majority of extra-adrenal sympathoblasts arise from the migratory neural crest. In humans, this process persists during several weeks of development within the large intra-adrenal ganglia-like structures, which may also serve as reservoirs of originating cells in neuroblastoma.


Assuntos
Linhagem da Célula , Embrião de Mamíferos/metabolismo , Neuroblastoma/embriologia , Neuroblastoma/genética , Análise de Célula Única , Sistema Simpático-Suprarrenal/embriologia , Transcriptoma/genética , Animais , Células Cromafins/metabolismo , Células Cromafins/patologia , Análise por Conglomerados , Desenvolvimento Embrionário , Regulação da Expressão Gênica no Desenvolvimento , Regulação Neoplásica da Expressão Gênica , Humanos , Lactente , Camundongos , Células-Tronco Neurais/metabolismo , Neuroblastoma/patologia , Células de Schwann/metabolismo , Células de Schwann/patologia , Microambiente Tumoral
10.
Nat Commun ; 12(1): 2148, 2021 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-33846320

RESUMO

Deregulation of chromatin modifiers plays an essential role in the pathogenesis of medulloblastoma, the most common paediatric malignant brain tumour. Here, we identify a BMI1-dependent sensitivity to deregulation of inositol metabolism in a proportion of medulloblastoma. We demonstrate mTOR pathway activation and metabolic adaptation specifically in medulloblastoma of the molecular subgroup G4 characterised by a BMI1High;CHD7Low signature and show this can be counteracted by IP6 treatment. Finally, we demonstrate that IP6 synergises with cisplatin to enhance its cytotoxicity in vitro and extends survival in a pre-clinical BMI1High;CHD7Low xenograft model.


Assuntos
Adaptação Fisiológica , Neoplasias Cerebelares/genética , Epigênese Genética , Inositol/farmacologia , Meduloblastoma/genética , Adaptação Fisiológica/efeitos dos fármacos , Animais , Contagem de Células , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cisplatino/farmacologia , Proteínas de Ligação a DNA/metabolismo , Sinergismo Farmacológico , Epigênese Genética/efeitos dos fármacos , Humanos , Camundongos , Células-Tronco Neurais/metabolismo , Consumo de Oxigênio/efeitos dos fármacos , Fosfatidilinositóis/metabolismo , Complexo Repressor Polycomb 1/metabolismo , Regiões Promotoras Genéticas/genética , Proteínas Proto-Oncogênicas/metabolismo , Transdução de Sinais , Proteínas com Domínio T , Serina-Treonina Quinases TOR/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Int J Mol Sci ; 22(7)2021 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-33810614

RESUMO

We studied cell proliferation in the postnatal mouse brain between the ages of 2 and 30 months and identified four compartments with different densities of proliferating cells. The first identified compartment corresponds to the postnatal pallial neurogenic (PPN) zone in the telencephalon; the second to the subpallial postnatal neurogenic (SPPN) zone in the telencephalon; the third to the white matter bundles in the telencephalon; and the fourth to all brain parts outside of the other three compartments. We estimated that about 3.4 million new cells, including 0.8 million in the subgranular zone (SGZ) in the hippocampus, are produced in the PPN zone. About 21 million new cells, including 10 million in the subependymal zone (SEZ) in the lateral walls of the lateral ventricle and 2.7 million in the rostral migratory stream (RMS), are produced in the SPPN zone. The third and fourth compartments together produced about 31 million new cells. The analysis of cell proliferation in neurogenic zones shows that postnatal neurogenesis is the direct continuation of developmental neurogenesis in the telencephalon and that adult neurogenesis has characteristics of the late developmental process. As a developmental process, adult neurogenesis supports only compensatory regeneration, which is very inefficient.


Assuntos
Encéfalo/crescimento & desenvolvimento , Proliferação de Células , Hipocampo/crescimento & desenvolvimento , Telencéfalo/crescimento & desenvolvimento , Animais , Mapeamento Encefálico , Movimento Celular , Ventrículos Laterais/diagnóstico por imagem , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Células-Tronco Neurais/metabolismo , Neurogênese , Neurônios/metabolismo , Regeneração
12.
Mol Cell ; 81(12): 2625-2639.e5, 2021 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-33887196

RESUMO

The Polycomb repressive complex 2 (PRC2) is an essential epigenetic regulator that deposits repressive H3K27me3. PRC2 subunits form two holocomplexes-PRC2.1 and PRC2.2-but the roles of these two PRC2 assemblies during differentiation are unclear. We employed auxin-inducible degradation to deplete PRC2.1 subunit MTF2 or PRC2.2 subunit JARID2 during differentiation of embryonic stem cells (ESCs) to neural progenitors (NPCs). Depletion of either MTF2 or JARID2 resulted in incomplete differentiation due to defects in gene regulation. Distinct sets of Polycomb target genes were derepressed in the absence of MTF2 or JARID2. MTF2-sensitive genes were marked by H3K27me3 in ESCs and remained silent during differentiation, whereas JARID2-sensitive genes were preferentially active in ESCs and became newly repressed in NPCs. Thus, MTF2 and JARID2 contribute non-redundantly to Polycomb silencing, suggesting that PRC2.1 and PRC2.2 have distinct functions in maintaining and establishing, respectively, Polycomb repression during differentiation.


Assuntos
Complexo Repressor Polycomb 2/metabolismo , Animais , Diferenciação Celular/fisiologia , Células-Tronco Embrionárias/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/genética , Histonas/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Células-Tronco Neurais/metabolismo , Complexo Repressor Polycomb 2/fisiologia , Proteínas do Grupo Polycomb/metabolismo , Proteínas do Grupo Polycomb/fisiologia , Ligação Proteica/genética
13.
Genes Cells ; 26(6): 399-410, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33811429

RESUMO

An expanded and folded neocortex is characteristic of higher mammals, including humans and other primates. The neocortical surface area was dramatically enlarged during the course of mammalian brain evolution from lissencephalic to gyrencephalic mammals, and this bestowed higher cognitive functions especially to primates, including humans. In this study, we generated transgenic (Tg) mice in which the expression of Sonic hedgehog (Shh) could be controlled in neural stem cells (NSCs) and neural progenitors by using the Tet-on system. Shh overexpression during embryogenesis promoted the symmetric proliferative division of NSCs in the neocortical region, leading to the expansion of lateral ventricles and tangential extension of the ventricular zone. Moreover, Shh-overexpressing Tg mice showed dramatic expansion of the neocortical surface area and exhibited a wrinkled brain when overexpression was commenced at early stages of neural development. These results indicate that Shh is able to increase the neocortical NSCs and contribute to expansion of the neocortex.


Assuntos
Proteínas Hedgehog/metabolismo , Neocórtex/metabolismo , Células-Tronco Neurais/citologia , Células-Tronco Neurais/metabolismo , Animais , Biomarcadores/metabolismo , Diferenciação Celular , Proliferação de Células , Ventrículos Cerebrais/metabolismo , Regulação da Expressão Gênica , Camundongos Transgênicos , Neurônios/citologia , Transdução de Sinais
14.
Mol Biol Rep ; 48(4): 3549-3559, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33866496

RESUMO

This study investigated the differentiation of transplanted transplanted mesenchymal stem cells MSCs into neuron-like cells, repair of erectile dysfunction (ED), and synergy of MSCs seeded to nanofibrous scaffolds with after transplantation around the injured cavernous nerve (CN) of rats. The synthesized polymer was electrospun in a rotating drum to prepare nanofiber meshes (NMs). Human MSCs were prepared and confirmed. Eight-week-old male Sprague-Dawley rats were divided into five groups of six each: group 1-sham operation; group 2-CN injury; group 3-MSCs treatment after CN injury; group 4-nanofibrous scaffold treatment after CN injury; and group 5-post-CN injury treatment combining a nanofibrous scaffold and MSCs (nano-MSCs). In the latter group, the damaged CN was instantly surrounded by an MSC-containing a nanofibrous scaffold in the aftermath of injury. Morphological analysis and immuno-histochemical staining in relation to nerves (Tuj1, NF, MAP2, MBP and peripherin), endothelium (vWF), smooth muscle (SMA), neurofilament (NF), and apoptosis (TUNEL) were performed. We evaluated the mean proportion expressed as a percentage of the ratio of muscle to collagen of penile cavernous smooth-muscle cells as well as the expression of cavernous SMA, NF, vWF, and TUNEL makers. Compared to the group free of CN injury, erectile function was markedly reduced in the group with CN injury at 2 and 4 weeks (p < 0.05). By contrast, compared to the sham operation group, erectile function was better in the group with MSC transplantation (p < 0.05). Similarly, by comparison to the group solely with hMSCs, erectile function was better in the group with nano-MSC transplantation (p < 0.05). Transplantation of MSCs demonstrated the neuronal differentiation. By contrast to MSCs on their own, neuronal differentiation was more significantly expressed in nano-MSCs. The mean proportion expressed as a percentage of the ratio of muscle to collagen of penile cavernous smooth-muscle cells, the expression of cavernous SMA, NF, vWF, and apoptosis improved in the cavernosum after transplantation. NMs showed synergy with MSCs for the repair of erectile dysfunction. Transplanted MSCs differentiated into neuron-like cells and repaired erectile dysfunction in the rats with CN injury. Transplanted MSCs increased the mean percentage of the collagen area of the caversnosum as well as the expression levels of cavernous neuronal, endothelial, smooth-muscle markers, and apoptosis.


Assuntos
Diferenciação Celular , Disfunção Erétil/terapia , Transplante de Células-Tronco Mesenquimais/métodos , Regeneração Nervosa , Traumatismos dos Nervos Periféricos/terapia , Actinas/genética , Actinas/metabolismo , Animais , Apoptose , Células Cultivadas , Humanos , Masculino , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Células-Tronco Neurais/citologia , Células-Tronco Neurais/metabolismo , Proteínas de Neurofilamentos/genética , Proteínas de Neurofilamentos/metabolismo , Pênis/inervação , Poliésteres/química , Ratos , Ratos Sprague-Dawley , Tecidos Suporte/química , Tubulina (Proteína)/metabolismo
15.
Oxid Med Cell Longev ; 2021: 6657944, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33791072

RESUMO

Long noncoding RNAs (lncRNAs) have attracted extensive attention due to their regulatory role in various cellular processes. Emerging studies have indicated that lncRNAs are expressed to varying degrees after the growth and development of the nervous system as well as injury and degeneration, thus affecting various physiological processes of the nervous system. In this review, we have compiled various reported lncRNAs related to the growth and development of central and peripheral nerves and pathophysiology (including advanced nerve centers, spinal cord, and peripheral nervous system) and explained how these lncRNAs play regulatory roles through their interactions with target-coding genes. We believe that a full understanding of the regulatory function of lncRNAs in the nervous system will contribute to understand the molecular mechanism of changes after nerve injury and will contribute to discover new diagnostic markers and therapeutic targets for nerve injury diseases.


Assuntos
Sistema Nervoso/metabolismo , RNA Longo não Codificante/genética , Animais , Diferenciação Celular/genética , Humanos , Regeneração Nervosa/genética , Sistema Nervoso/crescimento & desenvolvimento , Doenças do Sistema Nervoso/genética , Doenças do Sistema Nervoso/patologia , Células-Tronco Neurais/metabolismo , RNA Longo não Codificante/metabolismo
16.
Int J Mol Sci ; 22(8)2021 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-33920124

RESUMO

Central nervous system tumor with BCL6-corepressor internal tandem duplication (CNS-BCOR ITD) is a malignant entity characterized by recurrent alterations in exon 15 encoding the essential binding domain for the polycomb repressive complex (PRC). In contrast to deletion or truncating mutations seen in other tumors, BCOR expression is upregulated in CNS-BCOR ITD, and a distinct oncogenic mechanism has been suggested. However, the effects of this change on the biology of neuroepithelial cells is poorly understood. In this study, we introduced either wildtype BCOR or BCOR-ITD into human and murine neural stem cells and analyzed them with quantitative RT-PCR and RNA-sequencing, as well as growth, clonogenicity, and invasion assays. In human cells, BCOR-ITD promoted derepression of PRC2-target genes compared to wildtype BCOR. A similar effect was found in clinical specimens from previous studies. However, no growth advantage was seen in the human neural stem cells expressing BCOR-ITD, and long-term models could not be established. In the murine cells, both wildtype BCOR and BCOR-ITD overexpression affected cellular differentiation and histone methylation, but only BCOR-ITD increased cellular growth, invasion, and migration. BCOR-ITD overexpression drives transcriptional changes, possibly due to altered PRC function, and contributes to the oncogenic transformation of neural precursors.


Assuntos
Proliferação de Células/genética , Neoplasias do Sistema Nervoso Central/genética , Proteínas do Grupo Polycomb/genética , Proteínas Proto-Oncogênicas/genética , Proteínas Repressoras/genética , Animais , Linhagem Celular Tumoral , Neoplasias do Sistema Nervoso Central/patologia , Duplicação Gênica/genética , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Camundongos , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , Células-Tronco Neurais/metabolismo , Células-Tronco Neurais/patologia , Sequências de Repetição em Tandem/genética
17.
Biomed Res Int ; 2021: 5542545, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33834065

RESUMO

Background: Recent studies suggest a correlation between the reduced Sirt-1 expression with Alzheimer's diseases (AD) and depression, respectively, suggesting a possible pathogenic role of the altered Sirt-1 expression in neuronal degenerative diseases, such as AD and depression. However, the molecular mechanisms underlying how Sirt-1 reduction impairs neuronal functions remain unknown. Methods: We used the SK-N-SH neuroblastoma cells to study the role of Sirt-1 expression on physiological roles in neuronal cells. Gain of Sirt-1 was achieved by transiently transfecting Sirt-1 expression plasmid. Sirt-1-specific shRNA was used to elucidate the role of Sirt-1 loss of function. CCK-8 (Cell Counting Kit-8) assay and flow cytometry were used to evaluate cell proliferation. Semiquantitative western blotting was used to detect relative protein levels. A further luciferase reporter gene assay was employed to examine the effect of Sirt-1 expression on the transcriptional activity of p53. RT-qPCR was used to determine the mRNA levels of p21, Bax, and Bcl-2, which were the downstream target genes of p53. Results: Sirt-1 suppressed the p53 downstream gene p21 transcription, while shRNA-mediated Sirt-1 knockdown resulted in a significant increase in p21 expression, implying a possibility that Sirt-1 promotes neuron proliferation through suppressing p53 transcriptional activity. The mRNA and protein levels of p53 were not affected by the altered Sirt-1 expression, suggesting that Sirt-1 regulates the transcriptional regulatory activity of p53 rather than p53 expression. Indeed, we further confirmed that Sirt-1 appeared to inhibit p53 transcriptional activity by attenuating its acetylation and resulted in a decrease of p53's binding to the p21 promoter. Overexpressed Sirt-1 scavenged reactive oxygen species (ROS) production in SK-N-SH with H2O2. Knockdown of Sirt-1 presented opposite effect; the addition of EX527 (Sirt-1 inhibitor) increased ROS accumulation. Conclusions: Oxidative stress induces Sirt-1 in neuron cells, and Sirt-1 promotes proliferation in SK-N-SH cells, which protects them from oxidative stress-induced cell death, potentially via suppressing the transcriptional activity of p53. These results provide a molecular explanation underlying how the reduced Sirt-1 potentially causes the AD and depression-related diseases, supporting the idea that Sirt-1 can possibly be used as a diagnostic biomarker and/or therapeutic drug target for the AD and depression-related diseases.


Assuntos
Estresse Oxidativo , Substâncias Protetoras/metabolismo , Sirtuína 1/metabolismo , Acetilação/efeitos dos fármacos , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Humanos , Peróxido de Hidrogênio/toxicidade , Lisina/metabolismo , Células-Tronco Neurais/efeitos dos fármacos , Células-Tronco Neurais/metabolismo , Células-Tronco Neurais/patologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/patologia , Estresse Oxidativo/efeitos dos fármacos , Regiões Promotoras Genéticas/genética , Ligação Proteica/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transcrição Genética/efeitos dos fármacos , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
18.
Int J Mol Sci ; 22(9)2021 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-33922276

RESUMO

Sialidosis, caused by a genetic deficiency of the lysosomal sialidase gene (NEU1), is a systemic disease involving various tissues and organs, including the nervous system. Understanding the neurological dysfunction and pathology associated with sialidosis remains a challenge, partially due to the lack of a human model system. In this study, we have generated two types of induced pluripotent stem cells (iPSCs) with sialidosis-specific NEU1G227R and NEU1V275A/R347Q mutations (sialidosis-iPSCs), and further differentiated them into neural precursor cells (iNPCs). Characterization of NEU1G227R- and NEU1V275A/R347Q- mutated iNPCs derived from sialidosis-iPSCs (sialidosis-iNPCs) validated that sialidosis-iNPCs faithfully recapitulate key disease-specific phenotypes, including reduced NEU1 activity and impaired lysosomal and autophagic function. In particular, these cells showed defective differentiation into oligodendrocytes and astrocytes, while their neuronal differentiation was not notably affected. Importantly, we found that the phenotypic defects of sialidosis-iNPCs, such as impaired differentiation capacity, could be effectively rescued by the induction of autophagy with rapamycin. Our results demonstrate the first use of a sialidosis-iNPC model with NEU1G227R- and NEU1V275A/R347Q- mutation(s) to study the neurological defects of sialidosis, particularly those related to a defective autophagy-lysosome pathway, and may help accelerate the development of new drugs and therapeutics to combat sialidosis and other LSDs.


Assuntos
Astrócitos/patologia , Células-Tronco Pluripotentes Induzidas/patologia , Mucolipidoses/patologia , Células-Tronco Neurais/patologia , Neuraminidase/metabolismo , Oligodendroglia/patologia , Teratoma/patologia , Astrócitos/metabolismo , Autofagia , Diferenciação Celular , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Lisossomos , Mucolipidoses/genética , Mucolipidoses/metabolismo , Mutação , Células-Tronco Neurais/metabolismo , Neuraminidase/genética , Oligodendroglia/metabolismo , Fenótipo , Teratoma/genética , Teratoma/metabolismo
19.
Yakugaku Zasshi ; 141(3): 343-348, 2021.
Artigo em Japonês | MEDLINE | ID: mdl-33642502

RESUMO

We have been investigating the physiological and pathological roles of stem cells and progenitor cells in the central nervous system using multimodal imaging methods, including positron emission tomography (PET), in vivo optical imaging, and light as well as electron microscopy. Furthermore, we generated transgenic rats for selective ablation of these cells. Imaging studies have demonstrated the proliferation and dynamics of neural stem cells in neurogenic regions and glial progenitor cells expressing a chondroitin sulfate proteoglycan (neuron-glial antigen 2; NG2) in the brain of adult rodents. Glial progenitor cells change their direction of differentiation into mature oligodendrocytes or astrocytes by neural activity following their proliferation. This phenomenon was thought to control the local tissue structure for maintenance of moderate neural activity. Furthermore, selective ablation of glial progenitor cells in the brain induced defects of neurons via neuroinflammation with microglial activation and proinflammatory cytokine production in the region. Thus, we have proposed a novel concept that glial progenitor cells regulate the neuro-immune system in the central nervous system, in addition to their role as germinal cells, giving rise to mature glial cells. Neuroinflammation is associated with the onset and progression of depression, chronic fatigue syndrome, and neurodegenerative diseases, including Alzheimer's disease. Anti-inflammatory effects of glial progenitor cells might bring about the possibility of these cells as the new therapeutic targets for such neurological disorders.


Assuntos
Encéfalo/citologia , Encéfalo/fisiologia , Células-Tronco Neurais/fisiologia , Neuroglia/fisiologia , Animais , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Diferenciação Celular , Proliferação de Células , Proteoglicanas de Sulfatos de Condroitina/metabolismo , Citocinas/metabolismo , Depressão/etiologia , Síndrome de Fadiga Crônica/etiologia , Inflamação , Mediadores da Inflamação/metabolismo , Células-Tronco Neurais/metabolismo , Doenças Neurodegenerativas/etiologia , Neuroglia/metabolismo , Neuroimagem/métodos , Ratos
20.
EMBO Rep ; 22(5): e52130, 2021 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-33751817

RESUMO

The final size and function of the adult central nervous system (CNS) are determined by neuronal lineages generated by neural stem cells (NSCs) in the developing brain. In Drosophila, NSCs called neuroblasts (NBs) reside within a specialised microenvironment called the glial niche. Here, we explore non-autonomous glial regulation of NB proliferation. We show that lipid droplets (LDs) which reside within the glial niche are closely associated with the signalling molecule Hedgehog (Hh). Under physiological conditions, cortex glial Hh is autonomously required to sustain niche chamber formation. Upon FGF-mediated cortex glial overgrowth, glial Hh non-autonomously activates Hh signalling in the NBs, which in turn disrupts NB cell cycle progression and its ability to produce neurons. Glial Hh's ability to signal to NB is further modulated by lipid storage regulator lipid storage droplet-2 (Lsd-2) and de novo lipogenesis gene fatty acid synthase 1 (Fasn1). Together, our data suggest that glial-derived Hh modified by lipid metabolism mechanisms can affect the neighbouring NB's ability to proliferate and produce neurons.


Assuntos
Proteínas de Drosophila , Células-Tronco Neurais , Animais , Proliferação de Células , Drosophila/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Proteínas Hedgehog/genética , Metabolismo dos Lipídeos , Células-Tronco Neurais/metabolismo
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