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1.
Nat Commun ; 12(1): 4855, 2021 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-34381044

RESUMO

The vertebrate brain consists of diverse neuronal types, classified by distinct anatomy and function, along with divergent transcriptomes and proteomes. Defining the cell-type specific neuroproteomes is important for understanding the development and functional organization of neural circuits. This task remains challenging in complex tissue, due to suboptimal protein isolation techniques that often result in loss of cell-type specific information and incomplete capture of subcellular compartments. Here, we develop a genetically targeted proximity labeling approach to identify cell-type specific subcellular proteomes in the mouse brain, confirmed by imaging, electron microscopy, and mass spectrometry. We virally express subcellular-localized APEX2 to map the proteome of direct and indirect pathway spiny projection neurons in the striatum. The workflow provides sufficient depth to uncover changes in the proteome of striatal neurons following chemogenetic activation of Gαq-coupled signaling cascades. This method enables flexible, cell-type specific quantitative profiling of subcellular proteome snapshots in the mouse brain.


Assuntos
Ascorbato Peroxidases/metabolismo , Núcleo Celular/metabolismo , Corpo Estriado/metabolismo , Proteoma/metabolismo , Animais , Ascorbato Peroxidases/genética , Corpo Estriado/citologia , Citosol/metabolismo , Espectrometria de Massas , Camundongos , Vias Neurais , Neurônios/citologia , Neurônios/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Transdução de Sinais , Coloração e Rotulagem , Fluxo de Trabalho
2.
Molecules ; 26(16)2021 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-34443598

RESUMO

Apocynin (APO) is a known multi-enzymatic complexed compound, employed as a viable NADPH oxidase (NOX) inhibitor, extensively used in both traditional and modern-day therapeutic strategies to combat neuronal disorders. However, its therapeutic efficacy is limited by lower solubility and lesser bioavailability; thus, a suitable nanocarrier system to overcome such limitations is needed. The present study is designed to fabricate APO-loaded polymeric nanoparticles (APO-NPs) to enhance its therapeutic efficacy and sustainability in the biological system. The optimized APO NPs in the study exhibited 103.6 ± 6.8 nm and -13.7 ± 0.43 mV of particle size and zeta potential, respectively, along with further confirmation by TEM. In addition, the antioxidant (AO) abilities quantified by DPPH and nitric oxide scavenging assays exhibited comparatively higher AO potential of APO-NPs than APO alone. An in-vitro release profile displayed a linear diffusion pattern of zero order kinetics for APO from the NPs, followed by its cytotoxicity evaluation on the PC12 cell line, which revealed minimal toxicity with higher cell viability, even after treatment with a stress inducer (H2O2). The stability of APO-NPs after six months showed minimal AO decline in comparison to APO only, indicating that the designed nano-formulation enhanced therapeutic efficacy for modulating NOX-mediated ROS generation.


Assuntos
Acetofenonas/química , Acetofenonas/farmacologia , Peróxido de Hidrogênio/farmacologia , NADPH Oxidases/metabolismo , Nanopartículas/química , Neurônios/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Animais , Sobrevivência Celular/efeitos dos fármacos , Neurônios/citologia , Neurônios/metabolismo , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/farmacologia , Células PC12 , Ratos
3.
Nature ; 596(7871): 257-261, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34349261

RESUMO

An animal's nervous system changes as its body grows from birth to adulthood and its behaviours mature1-8. The form and extent of circuit remodelling across the connectome is unknown3,9-15. Here we used serial-section electron microscopy to reconstruct the full brain of eight isogenic Caenorhabditis elegans individuals across postnatal stages to investigate how it changes with age. The overall geometry of the brain is preserved from birth to adulthood, but substantial changes in chemical synaptic connectivity emerge on this consistent scaffold. Comparing connectomes between individuals reveals substantial differences in connectivity that make each brain partly unique. Comparing connectomes across maturation reveals consistent wiring changes between different neurons. These changes alter the strength of existing connections and create new connections. Collective changes in the network alter information processing. During development, the central decision-making circuitry is maintained, whereas sensory and motor pathways substantially remodel. With age, the brain becomes progressively more feedforward and discernibly modular. Thus developmental connectomics reveals principles that underlie brain maturation.


Assuntos
Encéfalo/citologia , Encéfalo/crescimento & desenvolvimento , Caenorhabditis elegans/citologia , Conectoma , Modelos Neurológicos , Vias Neurais , Sinapses/fisiologia , Envelhecimento/metabolismo , Animais , Encéfalo/anatomia & histologia , Encéfalo/ultraestrutura , Caenorhabditis elegans/anatomia & histologia , Caenorhabditis elegans/crescimento & desenvolvimento , Caenorhabditis elegans/ultraestrutura , Individualidade , Interneurônios/citologia , Microscopia Eletrônica , Neurônios/citologia , Comportamento Estereotipado
4.
Int J Mol Sci ; 22(15)2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34360854

RESUMO

Ketamine is a clinical anesthetic and antidepressant. Although ketamine is a known NMDA receptor antagonist, the mechanisms contributing to antidepression are unclear. This present study examined the loci and duration of ketamine's actions, and the involvement of NMDA receptors. Local field potentials were recorded from the CA1 region of mouse hippocampal slices. Ketamine was tested at antidepressant and anesthetic concentrations. Effects of NMDA receptor antagonists APV and MK-801, GABA receptor antagonist bicuculline, and a potassium channel blocker TEA were also studied. Ketamine decreased population spike amplitudes during application, but a long-lasting increase in amplitudes was seen during washout. Bicuculline reversed the acute effects of ketamine, but the washout increase was not altered. This long-term increase was statistically significant, sustained for >2 h, and involved postsynaptic mechanisms. A similar effect was produced by MK-801, but was only partially evident with APV, demonstrating the importance of the NMDA receptor ion channel block. TEA also produced a lasting excitability increase, indicating a possible involvement of potassium channel block. This is this first report of a long-lasting increase in excitability following ketamine exposure. These results support a growing literature that increased GABA inhibition contributes to ketamine anesthesia, while increased excitatory transmission contributes to its antidepressant effects.


Assuntos
Anestésicos/farmacologia , Antidepressivos/farmacologia , Hipocampo/efeitos dos fármacos , Ketamina/farmacologia , Neurônios/efeitos dos fármacos , Transmissão Sináptica/efeitos dos fármacos , Animais , Hipocampo/citologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/citologia , Receptores de N-Metil-D-Aspartato/metabolismo
5.
Am J Hum Genet ; 108(9): 1647-1668, 2021 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-34416157

RESUMO

Interpretation of the function of non-coding risk loci for neuropsychiatric disorders and brain-relevant traits via gene expression and alternative splicing quantitative trait locus (e/sQTL) analyses is generally performed in bulk post-mortem adult tissue. However, genetic risk loci are enriched in regulatory elements active during neocortical differentiation, and regulatory effects of risk variants may be masked by heterogeneity in bulk tissue. Here, we map e/sQTLs, and allele-specific expression in cultured cells representing two major developmental stages, primary human neural progenitors (n = 85) and their sorted neuronal progeny (n = 74), identifying numerous loci not detected in either bulk developing cortical wall or adult cortex. Using colocalization and genetic imputation via transcriptome-wide association, we uncover cell-type-specific regulatory mechanisms underlying risk for brain-relevant traits that are active during neocortical differentiation. Specifically, we identified a progenitor-specific eQTL for CENPW co-localized with common variant associations for cortical surface area and educational attainment.


Assuntos
Proteínas Cromossômicas não Histona/genética , Regulação da Expressão Gênica no Desenvolvimento , Neocórtex/metabolismo , Neurogênese/genética , Neurônios/metabolismo , Locos de Características Quantitativas , Alelos , Doença de Alzheimer/diagnóstico , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Diferenciação Celular , Cromatina/química , Cromatina/metabolismo , Proteínas Cromossômicas não Histona/metabolismo , Mapeamento Cromossômico , Escolaridade , Feminino , Feto , Predisposição Genética para Doença , Genoma Humano , Estudo de Associação Genômica Ampla , Humanos , Masculino , Neocórtex/citologia , Neocórtex/crescimento & desenvolvimento , Células-Tronco Neurais/citologia , Células-Tronco Neurais/metabolismo , Neurônios/citologia , Neuroticismo , Doença de Parkinson/diagnóstico , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , Cultura Primária de Células , Prognóstico , Esquizofrenia/diagnóstico , Esquizofrenia/genética , Esquizofrenia/metabolismo , Transcriptoma
6.
Nat Biomed Eng ; 5(8): 847-863, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34385693

RESUMO

The therapeutic efficacy of stem cells transplanted into an ischaemic brain depends primarily on the responses of the neurovascular unit. Here, we report the development and applicability of a functional neurovascular unit on a microfluidic chip as a microphysiological model of ischaemic stroke that recapitulates the function of the blood-brain barrier as well as interactions between therapeutic stem cells and host cells (human brain microvascular endothelial cells, pericytes, astrocytes, microglia and neurons). We used the model to track the infiltration of a number of candidate stem cells and to characterize the expression levels of genes associated with post-stroke pathologies. We observed that each type of stem cell showed unique neurorestorative effects, primarily by supporting endogenous recovery rather than through direct cell replacement, and that the recovery of synaptic activities is correlated with the recovery of the structural and functional integrity of the neurovascular unit rather than with the regeneration of neurons.


Assuntos
AVC Isquêmico/terapia , Dispositivos Lab-On-A-Chip , Transplante de Células-Tronco , Astrócitos/citologia , Astrócitos/metabolismo , Barreira Hematoencefálica/química , Barreira Hematoencefálica/metabolismo , Técnicas de Cocultura , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Humanos , Microglia/citologia , Microglia/metabolismo , Microvasos/citologia , Modelos Biológicos , Neurônios/citologia , Neurônios/metabolismo , Pericitos/citologia , Pericitos/metabolismo , Células-Tronco/citologia , Células-Tronco/metabolismo
7.
Oxid Med Cell Longev ; 2021: 5481228, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34457114

RESUMO

Peripheral nerve injury (PNI), resulting in the impairment of myelin sheaths and axons, seriously affects the transmission of sensory or motor nerves. Growth factors (GFs) provide a biological microenvironment for supporting nerve regrowth and have become a promising alternative for repairing PNI. As one number of intracellular growth factor family, fibroblast growth factor 13 (FGF13) was regard as a microtubule-stabilizing protein for regulating cytoskeletal plasticity and neuronal polarization. However, the therapeutic efficiency and underlying mechanism of FGF13 for treating PNI remained unknown. Here, the application of lentivirus that overexpressed FGF13 was delivered directly to the lesion site of transverse sciatic nerve for promoting peripheral nerve regeneration. Through behavioral analysis and histological and ultrastructure examinations, we found that FGF13 not only facilitated motor and sense functional recovery but also enhanced axon elongation and remyelination. Furthermore, pretreatment with FGF13 also promoted Schwann cell (SC) viability and upregulated the expression cellular microtubule-associated proteins in vitro PNI model. These data indicated FGF13 therapeutic effect was closely related to maintain cellular microtubule stability. Thus, this work provides the evident that FGF13-medicated microtubule stability is necessary for promoting peripheral nerve repair following PNI, highlighting the potential therapeutic value of FGF13 on ameliorating injured nerve recovery.


Assuntos
Fatores de Crescimento de Fibroblastos/metabolismo , Microtúbulos/química , Regeneração Nervosa , Neurônios/citologia , Traumatismos dos Nervos Periféricos/terapia , Recuperação de Função Fisiológica , Células de Schwann/citologia , Animais , Fatores de Crescimento de Fibroblastos/genética , Masculino , Neurônios/fisiologia , Traumatismos dos Nervos Periféricos/etiologia , Traumatismos dos Nervos Periféricos/patologia , Ratos , Ratos Sprague-Dawley , Células de Schwann/fisiologia
8.
Int J Mol Sci ; 22(15)2021 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-34361088

RESUMO

Mouse embryonic stem cells (ESCs) are useful tools for studying early embryonic development and tissue formation in mammals. Since neural lineage differentiation is a major subject of organogenesis, the development of efficient techniques to induce neural stem cells (NSCs) from pluripotent stem cells must be preceded. However, the currently available NSC differentiation methods are complicated and time consuming. This study aimed to propose an efficient method for the derivation of NSCs from mouse ESCs; early neural lineage commitment was achieved using a three-dimensional (3D) culture system, followed by a two-dimensional (2D) NSC derivation. To select early neural lineage cell types during differentiation, Sox1-GFP transgenic ESCs were used. They were differentiated into early neural lineage, forming spherical aggregates, which were subsequently picked for the establishment of 2D NSCs. The latter showed a morphology similar to that of brain-derived NSCs and expressed NSC markers, Musashi, Nestin, N-cadherin, and Sox2. Moreover, the NSCs could differentiate into three subtypes of neural lineages, neurons, astrocytes, and oligodendrocytes. The results together suggested that ESCs could efficiently differentiate into tripotent NSCs through specification in 3D culture (for approximately 10 days) followed by 2D culture (for seven days).


Assuntos
Técnicas de Cultura de Células/métodos , Células-Tronco Embrionárias Murinas/citologia , Células-Tronco Neurais/citologia , Neurônios/citologia , Células-Tronco Pluripotentes/citologia , Animais , Diferenciação Celular , Células Cultivadas , Camundongos , Células-Tronco Embrionárias Murinas/metabolismo , Nestina/metabolismo , Células-Tronco Neurais/metabolismo , Neurônios/metabolismo , Células-Tronco Pluripotentes/metabolismo , Fatores de Transcrição SOXB1/metabolismo
9.
Nat Commun ; 12(1): 4839, 2021 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-34376673

RESUMO

The ability to maintain a sequence of items in memory is a fundamental cognitive function. In the rodent hippocampus, the representation of sequentially organized spatial locations is reflected by the phase of action potentials relative to the theta oscillation (phase precession). We investigated whether the timing of neuronal activity relative to the theta brain oscillation also reflects sequence order in the medial temporal lobe of humans. We used a task in which human participants learned a fixed sequence of pictures and recorded single neuron and local field potential activity with implanted electrodes. We report that spikes for three consecutive items in the sequence (the preferred stimulus for each cell, as well as the stimuli immediately preceding and following it) were phase-locked at distinct phases of the theta oscillation. Consistent with phase precession, spikes were fired at progressively earlier phases as the sequence advanced. These findings generalize previous findings in the rodent hippocampus to the human temporal lobe and suggest that encoding stimulus information at distinct oscillatory phases may play a role in maintaining sequential order in memory.


Assuntos
Potenciais de Ação/fisiologia , Epilepsia/fisiopatologia , Aprendizagem/fisiologia , Neurônios/fisiologia , Ritmo Teta/fisiologia , Adolescente , Adulto , Epilepsia/diagnóstico , Feminino , Hipocampo/citologia , Hipocampo/fisiologia , Humanos , Masculino , Modelos Neurológicos , Neurônios/citologia , Estimulação Luminosa/métodos , Lobo Temporal/citologia , Lobo Temporal/fisiologia , Adulto Jovem
10.
Int J Mol Sci ; 22(14)2021 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-34299127

RESUMO

Reelin is a secretory protein involved in a variety of processes in forebrain development and function, including neuronal migration, dendrite growth, spine formation, and synaptic plasticity. Most of the function of Reelin is focused on excitatory neurons; however, little is known about its effects on inhibitory neurons and inhibitory synapses. In this study, we investigated the phosphatidylinositol 3-kinase/Akt pathway of Reelin in primary cortical and hippocampal neurons. Individual neurons were visualized using immunofluorescence to distinguish inhibitory neurons from excitatory neurons. Reelin-rich protein supplementation significantly induced the phosphorylation of Akt and ribosomal S6 protein in excitatory neurons, but not in most inhibitory neurons. In somatostatin-expressing inhibitory neurons, one of major subtypes of inhibitory neurons, Reelin-rich protein supplementation induced the phosphorylation of S6. Subsequently, we investigated whether or not Reelin-rich protein supplementation affected dendrite development in cultured inhibitory neurons. Reelin-rich protein supplementation did not change the total length of dendrites in inhibitory neurons in vitro. Finally, we examined the development of inhibitory synapses in primary hippocampal neurons and found that Reelin-rich protein supplementation significantly reduced the density of gephyrin-VGAT-positive clusters in the dendritic regions without changing the expression levels of several inhibitory synapse-related proteins. These findings indicate a new role for Reelin in specific groups of inhibitory neurons and the development of inhibitory synapses, which may contribute to the underlying cellular mechanisms of RELN-associated neurological disorders.


Assuntos
Moléculas de Adesão Celular Neuronais/metabolismo , Dendritos/fisiologia , Proteínas da Matriz Extracelular/metabolismo , Potenciais Pós-Sinápticos Inibidores , Proteínas do Tecido Nervoso/metabolismo , Inibição Neural , Plasticidade Neuronal , Neurônios/fisiologia , Serina Endopeptidases/metabolismo , Sinapses/fisiologia , Animais , Moléculas de Adesão Celular Neuronais/genética , Proteínas da Matriz Extracelular/genética , Hipocampo/citologia , Hipocampo/fisiologia , Camundongos , Camundongos Endogâmicos ICR , Proteínas do Tecido Nervoso/genética , Neurogênese , Neurônios/citologia , Serina Endopeptidases/genética , Transdução de Sinais
11.
Int J Mol Sci ; 22(14)2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34299143

RESUMO

Botulinum neurotoxins (BoNTs) are produced by Clostridium botulinum and are responsible for botulism, a fatal disorder of the nervous system mostly induced by food poisoning. Despite being one of the most potent families of poisonous substances, BoNTs are used for both aesthetic and therapeutic indications from cosmetic reduction of wrinkles to treatment of movement disorders. The increasing understanding of the biology of BoNTs and the availability of distinct toxin serotypes and subtypes offer the prospect of expanding the range of indications for these toxins. Engineering of BoNTs is considered to provide a new avenue for improving safety and clinical benefit from these neurotoxins. Robust, high-throughput, and cost-effective assays for BoNTs activity, yet highly relevant to the human physiology, have become indispensable for a successful translation of engineered BoNTs to the clinic. This review presents an emerging family of cell-based assays that take advantage of newly developed human pluripotent stem cells and neuronal function analyses technologies.


Assuntos
Bioensaio/métodos , Toxinas Botulínicas/farmacologia , Neurônios/citologia , Neurotoxinas/farmacologia , Células-Tronco Pluripotentes/citologia , Animais , Toxinas Botulínicas/classificação , Humanos , Neurônios/efeitos dos fármacos , Neurotoxinas/classificação , Células-Tronco Pluripotentes/efeitos dos fármacos
12.
Molecules ; 26(11)2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-34199597

RESUMO

The disruption of iron homeostasis is an important factor in the loss of mitochondrial function in neural cells, leading to neurodegeneration. Here, we assessed the protective action of gossypitrin (Gos), a naturally occurring flavonoid, on iron-induced neuronal cell damage using mouse hippocampal HT-22 cells and mitochondria isolated from rat brains. Gos was able to rescue HT22 cells from the damage induced by 100 µM Fe(II)-citrate (EC50 8.6 µM). This protection was linked to the prevention of both iron-induced mitochondrial membrane potential dissipation and ATP depletion. In isolated mitochondria, Gos (50 µM) elicited an almost complete protection against iron-induced mitochondrial swelling, the loss of mitochondrial transmembrane potential and ATP depletion. Gos also prevented Fe(II)-citrate-induced mitochondrial lipid peroxidation with an IC50 value (12.45 µM) that was about nine time lower than that for the tert-butylhydroperoxide-induced oxidation. Furthermore, the flavonoid was effective in inhibiting the degradation of both 15 and 1.5 mM 2-deoxyribose. It also decreased Fe(II) concentration with time, while increasing O2 consumption rate, and impairing the reduction of Fe(III) by ascorbate. Gos-Fe(II) complexes were detected by UV-VIS and IR spectroscopies, with an apparent Gos-iron stoichiometry of 2:1. Results suggest that Gos does not generally act as a classical antioxidant, but it directly affects iron, by maintaining it in its ferric form after stimulating Fe(II) oxidation. Metal ions would therefore be unable to participate in a Fenton-type reaction and the lipid peroxidation propagation phase. Hence, Gos could be used to treat neuronal diseases associated with iron-induced oxidative stress and mitochondrial damage.


Assuntos
Flavonoides/farmacologia , Ferro/efeitos adversos , Mitocôndrias/metabolismo , Neurônios/citologia , Trifosfato de Adenosina/metabolismo , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Ácido Cítrico/efeitos adversos , Compostos Ferrosos/efeitos adversos , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Mitocôndrias/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Ratos
13.
J Cell Sci ; 134(13)2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34313311

RESUMO

Dynamic co-regulation of the actin and microtubule subsystems enables the highly precise and adaptive remodelling of the cytoskeleton necessary for critical cellular processes, such as axonal pathfinding. The modes and mediators of this interpolymer crosstalk, however, are inadequately understood. We identify Fmn2, a non-diaphanous-related formin associated with cognitive disabilities, as a novel regulator of cooperative actin-microtubule remodelling in growth cones of both chick and zebrafish neurons. We show that Fmn2 stabilizes microtubules in the growth cones of cultured spinal neurons and in vivo. Super-resolution imaging revealed that Fmn2 facilitates guidance of exploratory microtubules along actin bundles into the chemosensory filopodia. Using live imaging, biochemistry and single-molecule assays, we show that a C-terminal domain in Fmn2 is necessary for the dynamic association between microtubules and actin filaments. In the absence of the cross-bridging function of Fmn2, filopodial capture of microtubules is compromised, resulting in destabilized filopodial protrusions and deficits in growth cone chemotaxis. Our results uncover a critical function for Fmn2 in actin-microtubule crosstalk in neurons and demonstrate that the modulation of microtubule dynamics via associations with F-actin is central to directional motility.


Assuntos
Actinas , Quimiotaxia , Forminas/genética , Cones de Crescimento , Neurônios/citologia , Citoesqueleto de Actina , Animais , Axônios , Galinhas , Microtúbulos , Peixe-Zebra
14.
FASEB J ; 35(8): e21769, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34288124

RESUMO

Neuronal activity regulates spatial distribution of the SUMOylation system in cytosolic and dendritic sites, which has been implicated in learning, memory, and underlying synaptic structural and functional remodeling in the hippocampus. However, the functional target proteins for activated small ubiquitin-like modifiers (SUMOs) and downstream molecular consequences behind long-term potentiation (LTP) of synaptic plasticity remain to be elucidated. In this study, we showed that N-methyl-D-aspartate receptor-mediated neuronal activity induced the covalent modification of cytosolic Akt1 by small ubiquitin-like modifier 1 (SUMO1) in rat cortical and hippocampal CA1 neurons. Protein inhibitor of activated STAT3 (PIAS3) was involved in the activity-induced Akt1 SUMO1-ylation, and K64 and K276 residues were major SUMOylated sites. Importantly, Akt1 SUMOylation at K64 and K276 enhanced its enzymatic activity and facilitated T308 phosphorylation. Furthermore, the N-terminal SAP domain of PIAS3 bound Akt1 directly. The disruption of Akt1-PIAS3 interaction by Tat-SAP, a synthetic Tat-fused cell-permeable peptide containing PIAS3 SAP domain, inhibited neuronal activity-induced Akt1 SUMOylation and impaired LTP expression and late phase LTP maintenance in the hippocampus. Correlatedly, Tat-SAP not only blocked the LTP-related extracellular signal-regulated kinase (ERK)1/2-Elk-1-brain-derived neurotrophic factor (BDNF)/Arc signaling, but also disrupted mammalian target of rapamycin (mTOR)-eIF4E-binding protein 1 (4E-BP1) pathway. These findings reveal an activity-induced Akt1 SUMOylation by PIAS3 that contributes to ERK1/2-BDNF/Arc and mTOR-4E-BP1 cascades, and in turn, long-lasting excitatory synaptic responses.


Assuntos
Hipocampo , Chaperonas Moleculares/metabolismo , Neurônios , Proteínas Inibidoras de STAT Ativados/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transmissão Sináptica , Animais , Células Cultivadas , Feminino , Células HEK293 , Hipocampo/citologia , Hipocampo/metabolismo , Humanos , Masculino , Neurônios/citologia , Neurônios/metabolismo , Fosforilação , Cultura Primária de Células , Ratos , Ratos Sprague-Dawley , Sumoilação
15.
Int J Mol Sci ; 22(14)2021 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-34299065

RESUMO

One of the changes brought about by Wallerian degeneration distal to nerve injury is disintegration of axonal mitochondria and consequent leakage of mitochondrial DNA (mtDNA)-the natural ligand for the toll-like receptor 9 (TLR9). RT-PCR and immunohistochemical or Western blot analyses were used to detect TLR9 mRNA and protein respectively in the lumbar (L4-L5) and cervical (C7-C8) dorsal root ganglia (DRG) ipsilateral and contralateral to a sterile unilateral sciatic nerve compression or transection. The unilateral sciatic nerve lesions led to bilateral increases in levels of both TLR9 mRNA and protein not only in the lumbar but also in the remote cervical DRG compared with naive or sham-operated controls. This upregulation of TLR9 was linked to activation of the Nuclear Factor kappa B (NFκB) and nuclear translocation of the Signal Transducer and Activator of Transcription 3 (STAT3), implying innate neuronal immune reaction and a pro-regenerative state in uninjured primary sensory neurons of the cervical DRG. The relationship of TLR9 to the induction of a pro-regenerative state in the cervical DRG neurons was confirmed by the shorter lengths of regenerated axons distal to ulnar nerve crush following a previous sciatic nerve lesion and intrathecal chloroquine injection compared with control rats. The results suggest that a systemic innate immune reaction not only triggers the regenerative state of axotomized DRG neurons but also induces a pro-regenerative state further along the neural axis after unilateral nerve injury.


Assuntos
Gânglios Espinais/citologia , Imunidade Inata/imunologia , Neurônios/citologia , Neurônios/imunologia , Fator de Transcrição STAT3/metabolismo , Neuropatia Ciática/terapia , Receptor Toll-Like 9/metabolismo , Animais , Masculino , Ratos , Ratos Wistar , Fator de Transcrição STAT3/genética , Neuropatia Ciática/imunologia , Neuropatia Ciática/metabolismo , Neuropatia Ciática/patologia , Receptor Toll-Like 9/genética
16.
Int J Mol Sci ; 22(14)2021 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-34299091

RESUMO

The differentiation of human pluripotent stem cells (hPSCs) to neural stem cells (NSCs) is the key initial event in neurogenesis and is thought to be dependent on the family of Wnt growth factors, their receptors and signaling proteins. The delineation of the transcriptional pathways that mediate Wnt-induced hPSCs to NSCs differentiation is vital for understanding the global genomic mechanisms of the development of NSCs and, potentially, the creation of new protocols in regenerative medicine. To understand the genomic mechanism of Wnt signaling during NSCs development, we treated hPSCs with Wnt activator (CHIR-99021) and leukemia inhibitory factor (LIF) in a chemically defined medium (N2B27) to induce NSCs, referred to as CLNSCs. The CLNSCs were subcultured for more than 40 passages in vitro; were positive for AP staining; expressed neural progenitor markers such as NESTIN, PAX6, SOX2, and SOX1; and were able to differentiate into three neural lineage cells: neurons, astrocytes, and oligodendrocytes in vitro. Our transcriptome analyses revealed that the Wnt and Hedgehog signaling pathways regulate hPSCs cell fate decisions for neural lineages and maintain the self-renewal of CLNSCs. One interesting network could be the deregulation of the Wnt/ß-catenin signaling pathway in CLNSCs via the downregulation of c-MYC, which may promote exit from pluripotency and neural differentiation. The Wnt-induced spinal markers HOXA1-4, HOXA7, HOXB1-4, and HOXC4 were increased, however, the brain markers FOXG1 and OTX2, were absent in the CLNSCs, indicating that CLNSCs have partial spinal cord properties. Finally, a CLNSC simple culture condition, when applied to hPSCs, supports the generation of NSCs, and provides a new and efficient cell model with which to untangle the mechanisms during neurogenesis.


Assuntos
Biomarcadores/análise , Células-Tronco Neurais/citologia , Neurogênese , Neurônios/citologia , Células-Tronco Pluripotentes/citologia , Transcriptoma , Via de Sinalização Wnt , Diferenciação Celular , Células Cultivadas , Humanos , Fator Inibidor de Leucemia/administração & dosagem , Células-Tronco Neurais/efeitos dos fármacos , Células-Tronco Neurais/metabolismo , Neurônios/metabolismo , Células-Tronco Pluripotentes/efeitos dos fármacos , Células-Tronco Pluripotentes/metabolismo
17.
Int J Mol Sci ; 22(13)2021 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-34206571

RESUMO

In recent years, a large population of immature neurons has been documented in the paralaminar nucleus of the primate amygdala. A substantial fraction of these immature neurons differentiate into mature neurons during postnatal development or following selective lesion of the hippocampus. Notwithstanding a growing number of studies on the origin and fate of these immature neurons, fundamental questions about the life and death of these neurons remain. Here, we briefly summarize what is currently known about the immature neurons present in the primate ventral amygdala during development and in adulthood, as well as following selective hippocampal lesions. We provide evidence confirming that the distribution of immature neurons extends to the anterior portions of the entorhinal cortex and layer II of the perirhinal cortex. We also provide novel arguments derived from stereological estimates of the number of mature and immature neurons, which support the view that the migration of immature neurons from the lateral ventricle accompanies neuronal maturation in the primate amygdala at all ages. Finally, we propose and discuss the hypothesis that increased migration and maturation of neurons in the amygdala following hippocampal dysfunction may be linked to behavioral alterations associated with certain neurodevelopmental disorders.


Assuntos
Tonsila do Cerebelo/citologia , Diferenciação Celular , Neurônios/citologia , Neurônios/metabolismo , Fatores Etários , Tonsila do Cerebelo/metabolismo , Animais , Biomarcadores , Contagem de Células , Morte Celular , Sobrevivência Celular , Expressão Gênica , Hipocampo/citologia , Hipocampo/metabolismo , Imuno-Histoquímica , Primatas , Lobo Temporal/citologia , Lobo Temporal/metabolismo
18.
Nat Commun ; 12(1): 4220, 2021 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-34244497

RESUMO

Prokineticin-2 (Prok2) is an important secreted protein likely involved in the pathogenesis of several acute and chronic neurological diseases through currently unidentified regulatory mechanisms. The initial mechanical injury of neurons by traumatic brain injury triggers multiple secondary responses including various cell death programs. One of these is ferroptosis, which is associated with dysregulation of iron and thiols and culminates in fatal lipid peroxidation. Here, we explore the regulatory role of Prok2 in neuronal ferroptosis in vitro and in vivo. We show that Prok2 prevents neuronal cell death by suppressing the biosynthesis of lipid peroxidation substrates, arachidonic acid-phospholipids, via accelerated F-box only protein 10 (Fbxo10)-driven ubiquitination, degradation of long-chain-fatty-acid-CoA ligase 4 (Acsl4), and inhibition of lipid peroxidation. Mice injected with adeno-associated virus-Prok2 before controlled cortical impact injury show reduced neuronal degeneration and improved motor and cognitive functions, which could be inhibited by Fbxo10 knockdown. Our study shows that Prok2 mediates neuronal cell deaths in traumatic brain injury via ferroptosis.


Assuntos
Lesões Encefálicas Traumáticas/patologia , Córtex Cerebral/patologia , Ferroptose , Hormônios Gastrointestinais/metabolismo , Neuropeptídeos/metabolismo , Adulto , Idoso , Animais , Lesões Encefálicas Traumáticas/cirurgia , Células Cultivadas , Córtex Cerebral/citologia , Coenzima A Ligases/metabolismo , Modelos Animais de Doenças , Proteínas F-Box/genética , Proteínas F-Box/metabolismo , Feminino , Hormônios Gastrointestinais/genética , Técnicas de Silenciamento de Genes , Humanos , Peroxidação de Lipídeos , Masculino , Camundongos , Pessoa de Meia-Idade , Mitocôndrias/patologia , Neurônios/citologia , Neurônios/patologia , Neuropeptídeos/genética , Fosfolipídeos/biossíntese , Cultura Primária de Células , Proteólise , Ubiquitinação
19.
Int J Mol Sci ; 22(12)2021 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-34200797

RESUMO

Although sex differences in the brain are prevalent, the knowledge about mechanisms underlying sex-related effects on normal and pathological brain functioning is rather poor. It is known that female and male brains differ in size and connectivity. Moreover, those differences are related to neuronal morphology, synaptic plasticity, and molecular signaling pathways. Among different processes assuring proper synapse functions are posttranslational modifications, and among them, S-palmitoylation (S-PALM) emerges as a crucial mechanism regulating synaptic integrity. Protein S-PALM is governed by a family of palmitoyl acyltransferases, also known as DHHC proteins. Here we focused on the sex-related functional importance of DHHC7 acyltransferase because of its S-PALM action over different synaptic proteins as well as sex steroid receptors. Using the mass spectrometry-based PANIMoni method, we identified sex-dependent differences in the S-PALM of synaptic proteins potentially involved in the regulation of membrane excitability and synaptic transmission as well as in the signaling of proteins involved in the structural plasticity of dendritic spines. To determine a mechanistic source for obtained sex-dependent changes in protein S-PALM, we analyzed synaptoneurosomes isolated from DHHC7-/- (DHHC7KO) female and male mice. Our data showed sex-dependent action of DHHC7 acyltransferase. Furthermore, we revealed that different S-PALM proteins control the same biological processes in male and female synapses.


Assuntos
Aciltransferases/fisiologia , Lipoilação , Plasticidade Neuronal , Neurônios/fisiologia , Processamento de Proteína Pós-Traducional , Sinapses/fisiologia , Transmissão Sináptica , Animais , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neurônios/citologia , Fatores Sexuais
20.
Science ; 373(6550): 111-117, 2021 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-34210887

RESUMO

Spatial patterns of gene expression manifest at scales ranging from local (e.g., cell-cell interactions) to global (e.g., body axis patterning). However, current spatial transcriptomics methods either average local contexts or are restricted to limited fields of view. Here, we introduce sci-Space, which retains single-cell resolution while resolving spatial heterogeneity at larger scales. Applying sci-Space to developing mouse embryos, we captured approximate spatial coordinates and whole transcriptomes of about 120,000 nuclei. We identify thousands of genes exhibiting anatomically patterned expression, leverage spatial information to annotate cellular subtypes, show that cell types vary substantially in their extent of spatial patterning, and reveal correlations between pseudotime and the migratory patterns of differentiating neurons. Looking forward, we anticipate that sci-Space will facilitate the construction of spatially resolved single-cell atlases of mammalian development.


Assuntos
Padronização Corporal/genética , Embrião de Mamíferos/embriologia , Desenvolvimento Embrionário/genética , Perfilação da Expressão Gênica/métodos , Análise de Célula Única/métodos , Transcriptoma , Animais , Atlas como Assunto , Encéfalo/embriologia , Movimento Celular , Camundongos , Neurogênese/genética , Neurônios/citologia
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