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1.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 48(3): 310-317, 2019 May 25.
Artigo em Chinês | MEDLINE | ID: mdl-31496164

RESUMO

The habenula is a small and bilateral nucleus above dorsal thalamus, which contains several different types of neurons. The habenula has extensive connections with the forebrain, septum and monoaminergic nuclei in the midbrain and brainstem. Habenula is known as an 'anti-reward' nucleus, which can be activated by aversive stimulus and negative reward prediction errors. Accumulating researchs have implicated that the habenula is involved in several behaviors crucial to survival. Meanwhile, the roles of the habenula in neuropsychiatric diseases have received increasing attention. This review summaries the studies regarding the roles of habenula and the related circuits in neuropathic pain, depression, drug addiction and schizophrenia, and discusses the possibility to use the habenula as a treatment target.


Assuntos
Transtorno Depressivo , Habenula , Humanos , Transtornos Mentais/patologia , Mesencéfalo , Neurônios/metabolismo , Recompensa
2.
Dokl Biochem Biophys ; 486(1): 184-186, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31367817

RESUMO

To perform optogenetic prosthetics of the retinal ganglion cell receptive field, a bicistronic genetic construct carrying the genes encoding the excitatory (channelrhodopsin-2) and inhibitory (Guillardia theta anion channelrhodopsin GtACR2) rhodopsins was created. A characteristic feature of this construct was the combination of these two genes with a mutant IRES insertion between them, which ensures the exact ratio of expression levels of the first and second genes in each transfected cell. Illumination of the central part of the neuron with light with a wavelength of 470 nm induced the action potential generation in the cell. Stimulation of the peripheral neuronal region with light induced the inhibition of action potential generation. Thus, using optogenetics methods, we simulated the ON-OFF interaction in the retinal ganglion cell receptive field. Theoretically, this construct can be used for optogenetic prosthetics of degenerative retina in the case of its delivery to the ganglion cells with lentiviral vectors.


Assuntos
Channelrhodopsins/genética , Optogenética/métodos , Retina/patologia , Células Ganglionares da Retina/metabolismo , Animais , Luz , Neurônios/citologia , Neurônios/metabolismo , Neurônios/efeitos da radiação , Ratos , Retina/efeitos da radiação , Células Ganglionares da Retina/patologia , Células Ganglionares da Retina/efeitos da radiação , Transfecção
3.
Adv Exp Med Biol ; 1173: 33-44, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31456204

RESUMO

With the development of research, more and more evidences suggested that mutations in the genes associated with brain iron metabolism induced diseases in the brain. Brain iron metabolism disorders might be one cause of neurodegenerative diseases. This review mainly summarizes the normal process of iron entry into the brain across the blood-brain barrier, and the distribution and transportation of iron among neurons and glial cells, as well as the underlying regulation mechanisms. To understand the mechanisms of iron metabolism in the brain will provide theoretical basis to prevent and cure brain diseases related to iron metabolism disorders.


Assuntos
Encéfalo/metabolismo , Distúrbios do Metabolismo do Ferro , Ferro/metabolismo , Barreira Hematoencefálica , Humanos , Neuroglia/metabolismo , Neurônios/metabolismo
4.
Chem Biodivers ; 16(8): e1900299, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31287220

RESUMO

The biotransformation of huperzine B (hupB), one of the characteristic bioactive constituents of the medicinal plant Huperzia serrata, by a fungal endophyte of the host plant was studied. One new compound, 8α,15α-epoxyhuperzine B (1), along with two known oxygenated hupB analogs, 16-hydroxyhuperzine B (2) and carinatumin B (3), was isolated and identified. The structures of all the isolates were deduced by spectroscopic methods including NMR, MS, IR, and UV spectra. The known compounds 2 and 3 were obtained from a microbial source for the first time. To the best of our knowledge, it is the first report on the microbial transformation of hupB and would facilitate further structural modification of hupB by chemo-enzymatic method. In the LPS-induced neuro-inflammation injury assay, 8α,15α-epoxyhuperzine B (1) exhibited moderate neuroprotective activity by increasing the viability of U251 cell lines with an EC50 of 40.1 nm.


Assuntos
Alcaloides/química , Huperzia/química , Alcaloides/metabolismo , Alcaloides/farmacologia , Biotransformação , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Humanos , Huperzia/metabolismo , Lipopolissacarídeos/toxicidade , Conformação Molecular , Neurônios/citologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Plantas Medicinais/química , Plantas Medicinais/metabolismo , Substâncias Protetoras/química , Substâncias Protetoras/farmacologia
5.
Toxicol Lett ; 314: 43-52, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31310794

RESUMO

Thioredoxin is an evolutionarily conserved antioxidant protein that plays a crucial role for fundamental cellular processes and embryonic development. Growing evidence support that Thioredoxin influences cellular response to chemicals insults, particularly those accompanying oxidative stress. The mechanisms underlying the functions of Thioredoxin1 in the embryonic development under the environmental toxicant exposure remain, however, largely unexplored. We report here that thioredoxin1 becomes differentially expressed in zebrafish embryos after exposure to 9 out of 11 environmental chemicals. In situ gene expression analysis show that thioredoxin1 is expressed in neurons, olfactory epithelia, liver and swim bladder under normal conditions. After MeHg exposure, however, thioredoxin1 is ectopically induced in the hair cells of the lateral line and in epithelia cells of the pharynx. Knockdown of Thioredoxin1 induces hydrocephalus and increases cell apoptosis in the brain ventricular epithelia cells. In comparison with 5% malformation in embryos injected with control morpholino, MeHg induces more than 77% defects in Thioredoxin1 knockdown embryos. Our data suggest that there is an association between hydrocephalus and Thioredoxin1 malfunction in embryonic development, and provide valuable information to elucidate the protective role of Thioredoxin1 against chemicals disruption.


Assuntos
Encéfalo/efeitos dos fármacos , Poluentes Ambientais/toxicidade , Hidrocefalia/induzido quimicamente , Tiorredoxinas/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Peixe-Zebra/metabolismo , Animais , Animais Geneticamente Modificados , Apoptose/efeitos dos fármacos , Encéfalo/embriologia , Encéfalo/metabolismo , Embrião não Mamífero/efeitos dos fármacos , Embrião não Mamífero/metabolismo , Embrião não Mamífero/patologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Regulação da Expressão Gênica no Desenvolvimento , Hidrocefalia/embriologia , Hidrocefalia/genética , Hidrocefalia/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/patologia , Estresse Oxidativo/efeitos dos fármacos , Tiorredoxinas/genética , Peixe-Zebra/embriologia , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/genética
6.
J Agric Food Chem ; 67(29): 8227-8234, 2019 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-31299148

RESUMO

The mechanisms underlying neurodegenerative diseases are not fully understood yet. However, an increasing amount of evidence has suggested that these disorders are related to oxidative stress. We reported herein that lipoamide (LM), a neutral amide derivative of lipoic acid (LA), could resist oxidative stress-mediated neuronal cell damage. LM is more potent than LA in alleviating hydrogen peroxide- or 6-hydroxydopamine-induced PC12 cell injury. Our results reveal that LM promotes the nuclear accumulation of NFE2-related factor 2 (Nrf2), following with the activation of expression of Nrf2-governed antioxidant and detoxifying enzymes. Notably, silencing Nrf2 gene annuls the protection of LM, which demonstrates that Nrf2 is engaged in this cytoprotection. Our findings suggest that LM might be used as a potential therapeutic candidate for oxidative stress-related neurological disorders.


Assuntos
Fator 2 Relacionado a NF-E2/metabolismo , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Ácido Tióctico/análogos & derivados , Animais , Elementos de Resposta Antioxidante/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/genética , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Células PC12 , Ratos , Transdução de Sinais/efeitos dos fármacos , Ácido Tióctico/farmacologia
7.
Nat Commun ; 10(1): 2947, 2019 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-31270320

RESUMO

To expand the toolbox of imaging in living cells, we have engineered a single-chain variable fragment binding the linear HA epitope with high affinity and specificity in vivo. The resulting probe, called the HA frankenbody, can light up in multiple colors HA-tagged nuclear, cytoplasmic, membrane, and mitochondrial proteins in diverse cell types. The HA frankenbody also enables state-of-the-art single-molecule experiments in living cells, which we demonstrate by tracking single HA-tagged histones in U2OS cells and single mRNA translation dynamics in both U2OS cells and neurons. Together with the SunTag, we also track two mRNA species simultaneously to demonstrate comparative single-molecule studies of translation can now be done with genetically encoded tools alone. Finally, we use the HA frankenbody to precisely quantify the expression of HA-tagged proteins in developing zebrafish embryos. The versatility of the HA frankenbody makes it a powerful tool for imaging protein dynamics in vivo.


Assuntos
Epitopos/metabolismo , Sondas Moleculares/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Imagem Individual de Molécula , Animais , Linhagem Celular Tumoral , Embrião não Mamífero/metabolismo , Proteínas de Fluorescência Verde/metabolismo , Neurônios/metabolismo , Biossíntese de Proteínas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas Recombinantes de Fusão/isolamento & purificação , Anticorpos de Cadeia Única/metabolismo , Coloração e Rotulagem , Peixe-Zebra/embriologia
8.
Nat Commun ; 10(1): 2907, 2019 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-31266958

RESUMO

Single-nucleus RNA-seq (snRNA-seq) enables the interrogation of cellular states in complex tissues that are challenging to dissociate or are frozen, and opens the way to human genetics studies, clinical trials, and precise cell atlases of large organs. However, such applications are currently limited by batch effects, processing, and costs. Here, we present an approach for multiplexing snRNA-seq, using sample-barcoded antibodies to uniquely label nuclei from distinct samples. Comparing human brain cortex samples profiled with or without hashing antibodies, we demonstrate that nucleus hashing does not significantly alter recovered profiles. We develop DemuxEM, a computational tool that detects inter-sample multiplets and assigns singlets to their sample of origin, and validate its accuracy using sex-specific gene expression, species-mixing and natural genetic variation. Our approach will facilitate tissue atlases of isogenic model organisms or from multiple biopsies or longitudinal samples of one donor, and large-scale perturbation screens.


Assuntos
Anticorpos/análise , Núcleo Celular/genética , Genômica/métodos , Análise de Célula Única/métodos , Idoso , Idoso de 80 Anos ou mais , Animais , Núcleo Celular/química , Núcleo Celular/metabolismo , DNA/genética , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/química , Neurônios/citologia , Neurônios/metabolismo , Córtex Pré-Frontal/química , Córtex Pré-Frontal/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
9.
Cell Biochem Funct ; 37(6): 432-442, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31318458

RESUMO

Advanced glycation end products (AGEs) are naturally occurring molecules that start to accumulate from embryonic developmental stages and form as part of normal ageing. When reducing sugars interact with and modify proteins or lipids, AGE production occurs. AGE formation accelerates in chronic hyperglycemic conditions, and high AGE levels have been associated with the pathogenesis of various diseases. In addition, enhanced levels of AGEs have been linked to delayed wound healing as seen in patients with diabetes mellitus. Research has provided numerous ways in which a high AGE concentration results in impaired wound healing, including oxidative stress, structural and functional changes to proteins important in wound repair, an enhanced inflammatory response by activation of transcription factors, and possible exaggerated apoptosis of cells necessary to the wound repair process. Apoptosis is a naturally occurring cell death process that is significant for normal tissue functioning and plays an important role in wound repair by preventing a prolonged inflammatory response and excessive scar formation. Abnormal apoptosis affects wound healing, resulting in slow healing wounds. This review will summarize the role of AGEs in wound healing, focusing on the mechanisms by which AGEs lead to apoptosis in various cell types. The review provides the way forward for medical research and molecular studies as it focuses on the mechanisms by which AGEs induce apoptosis in various cell types, including fibroblasts, osteoblasts, neuronal cells, and endothelial cells. Reviewing the mechanisms of AGE-linked apoptosis is important in understanding the impact of high AGE levels in delayed wound healing in diabetic patients due to abnormal apoptosis of cells necessary to the wound healing process.


Assuntos
Apoptose , Produtos Finais de Glicação Avançada/metabolismo , Cicatrização , Animais , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Fibroblastos/metabolismo , Fibroblastos/patologia , Humanos , Neurônios/metabolismo , Neurônios/patologia , Osteoblastos/metabolismo , Osteoblastos/patologia
10.
Life Sci ; 232: 116611, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31260683

RESUMO

PURPOSE: To observe the effect of dexmedetomidine (DEX) on mitochondrial apoptosis of hippocampal neurons in hypoxia/reoxygenation (H/R) brain injury in developing rats, and to investigate its regulatory mechanism on HIF-1α/p53 signaling pathway. METHODS: Hypoxia/reoxygenation model was used in this study. TUNEL assay was performed to detect cell apoptosis. Immunohistochemical analysis and Western-blotting analysis were conducted to detect Cytochrome-C (Cyt-c), APAF-1, Caspase-3, Neuroglobin (Ngb), HIF-1α and p53 expression. After 28 days, Morris water maze (MWM) was performed. RESULTS: 50 µg/kg DEX improved H/R-induced brain injury and inhibited mitochondrial apoptosis in rats. Western-blotting and Immunohistochemical results demonstrated that DEX could up-regulate Ngb through α2 receptor to inhibit H/R-induced mitochondrial apoptosis. In addition, by adding inhibitors yohimbine and 2-methoxyestradiol (2ME2), we found that DEX could activate HIF-1α/p53 signaling pathway. MWM test showed that DEX could enhance long-term learning and memory of H/R brain injury rats. CONCLUSION: DEX alleviates H/R-induced brain injury and mitochondrial apoptosis in developing rats through α2 receptor, which may be related to activation of HIF-1α/p53 signaling pathway to up-regulate the expression of Ngb.


Assuntos
Hipóxia Celular/efeitos dos fármacos , Dexmedetomidina/farmacologia , Hipocampo/efeitos dos fármacos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Neurônios/efeitos dos fármacos , Proteína Supressora de Tumor p53/metabolismo , Animais , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Hipocampo/metabolismo , Hipocampo/patologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Masculino , Mitocôndrias/metabolismo , Neurônios/metabolismo , Neurônios/patologia , Substâncias Protetoras/farmacologia , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteína Supressora de Tumor p53/efeitos dos fármacos
11.
Nature ; 571(7765): 349-354, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31292549

RESUMO

Ascidian embryos highlight the importance of cell lineages in animal development. As simple proto-vertebrates, they also provide insights into the evolutionary origins of cell types such as cranial placodes and neural crest cells. Here we have determined single-cell transcriptomes for more than 90,000 cells that span the entirety of development-from the onset of gastrulation to swimming tadpoles-in Ciona intestinalis. Owing to the small numbers of cells in ascidian embryos, this represents an average of over 12-fold coverage for every cell at every stage of development. We used single-cell transcriptome trajectories to construct virtual cell-lineage maps and provisional gene networks for 41 neural subtypes that comprise the larval nervous system. We summarize several applications of these datasets, including annotating the synaptome of swimming tadpoles and tracing the evolutionary origin of cell types such as the vertebrate telencephalon.


Assuntos
Linhagem da Célula/genética , Ciona intestinalis/citologia , Ciona intestinalis/genética , Análise de Célula Única , Transcriptoma , Animais , Sequência de Bases , Evolução Biológica , Ciona intestinalis/classificação , Ciona intestinalis/crescimento & desenvolvimento , Gastrulação , Redes Reguladoras de Genes , Larva/citologia , Larva/genética , Sistema Nervoso/citologia , Sistema Nervoso/metabolismo , Neurônios/citologia , Neurônios/metabolismo , Notocorda/citologia , Notocorda/embriologia , Especificidade de Órgãos , Sinapses/genética , Sinapses/metabolismo
12.
Life Sci ; 232: 116651, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31302195

RESUMO

The miR-19 family, including miR-19a, miR-19b-1 and miR-19b-2, arises from two different paralogous clusters miR-17-92 and miR-106a-363. Although it is identified as oncogenic miRNA, the miR-19 family has also been found to play important roles in regulating normal tissue development. The precise control of miR-19 family level is essential for keeping tissue homeostasis and normal development of organisms. Its dysregulation leads to dysplasia, disease and even cancer. Therefore, this review focuses on the roles of miR-19 family in the development and disease of heart, vessels and neurons to estimate the potential value of miR-19 family as diagnostic biomarker or therapeutic target of cardiac, neurological, and vascular diseases.


Assuntos
Vasos Sanguíneos/metabolismo , MicroRNAs/genética , Miocárdio/metabolismo , Neurônios/metabolismo , Biomarcadores/metabolismo , Humanos
13.
Yonsei Med J ; 60(7): 640-650, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31250578

RESUMO

PURPOSE: Alzheimer's disease (AD) is the most common neurodegenerative disease, with a rising prevalence worldwide. Long noncoding RNAs (lncRNAs) have been found to play important roles in the development and treatment of AD. However, the exact role of lncRNA nuclear enriched abundant transcript 1 (NEAT1) in neuronal damage in AD is largely unknown. MATERIALS AND METHODS: The AD model was established in SH-SY5Y and SK-N-SH cells via treatment with amyloid ß1-42 (Aß). The expression of NEAT1 and microRNA-107 (miR-107) was measured by quantitative real-time polymerase chain reaction. Cell viability and apoptosis were detected by MTT assay, immunocytochemistry, and flow cytometry. The expression of phosphorylated tau protein (p-Tau) was measured by Western blot. The interaction between NEAT1 and miR-107 was explored by bioinformatics analysis, luciferase activity, and RNA immunoprecipitation assays. RESULTS: NEAT1 expression was enhanced in Aß-treated SH-SY5Y and SK-N-SH cells, and its knockdown attenuated Aß-induced inhibition of viability and promotion of apoptosis and p-Tau levels. NEAT1 was indicated as a decoy of miR-107. miR-107 abundance was reduced in Aß-treated cells, and its overexpression reversed Aß-induced injury. Moreover, interference of miR-107 abated silencing of NEAT1-mediated inhibition of neuronal damage in Aß-treated SH-SY5Y and SK-N-SH cells. CONCLUSION: LncRNA NEAT1 aggravated Aß-induced neuronal damage by sponging miR-107, indicating a novel avenue for treatment of AD.


Assuntos
Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/toxicidade , MicroRNAs/genética , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Fragmentos de Peptídeos/toxicidade , RNA Longo não Codificante/genética , Apoptose/efeitos dos fármacos , Apoptose/genética , Linhagem Celular Tumoral , Humanos , Neurônios/patologia
14.
Cell Mol Life Sci ; 76(16): 3097-3116, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31172218

RESUMO

Metalloproteinases-such as matrix metalloproteinases (MMPs) and a disintegrin and metalloproteinases (ADAMs)-are involved in various diseases of the nervous system but also contribute to nervous system development, synaptic plasticity and neuroregeneration upon injury. MMPs and ADAMs proteolytically cleave many substrates including extracellular matrix components but also signaling molecules and receptors. During neuroinfectious disease with associated neuroinflammation, MMPs and ADAMs regulate blood-brain barrier breakdown, bacterial invasion, neutrophil infiltration and cytokine signaling. Specific and broad-spectrum inhibitors for MMPs and ADAMs have experimentally been shown to decrease neuroinflammation and brain damage in diseases with excessive neuroinflammation as a common denominator, such as pneumococcal meningitis and multiple sclerosis, thereby improving the disease outcome. Timing of metalloproteinase inhibition appears to be critical to effectively target the cascade of pathophysiological processes leading to brain damage without inhibiting the neuroregenerative effects of metalloproteinases. As the critical role of metalloproteinases in neuronal repair mechanisms and regeneration was only lately recognized, the original idea of chronic MMP inhibition needs to be conceptually revised. Recently accumulated research urges for a second chance of metalloproteinase inhibitors, which-when correctly applied and dosed-harbor the potential to improve the outcome of different neuroinflammatory diseases.


Assuntos
Proteínas ADAM/metabolismo , Metaloproteinases da Matriz/metabolismo , Esclerose Múltipla/patologia , Doenças do Sistema Nervoso/patologia , Barreira Hematoencefálica/metabolismo , Citocinas/metabolismo , Humanos , Esclerose Múltipla/metabolismo , Doenças do Sistema Nervoso/metabolismo , Neurônios/metabolismo , Neutrófilos/citologia , Neutrófilos/imunologia , Neutrófilos/metabolismo , Transdução de Sinais
15.
Cell Mol Biol Lett ; 24: 37, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31168302

RESUMO

Background: Accumulating evidence has shown that altered microRNA (miR) modulation is implicated in the pathologies of ischemic stroke. However, it is unclear whether and how hsa-miR-19a-3p mediates cerebral ischemic injury. Herein, we investigated the functional role of miR-19a-3p in cerebral ischemic injury and explored its underlying regulatory mechanism. Methods: In vivo ischemic/reperfusion (I/R) neuronal injury and in vitro oxygen-glucose deprivation (OGD) were established. Expression of miR-19a-3p was determined by quantitative real-time polymerase chain reaction (qRT-PCR). Glucose uptake, lactate production, and apoptosis were determined. ADIPOR2 was predicted as a target of miR-19a-3p in silico and experimentally validated by qRT-PCR, Western blot analysis and luciferase assay assays. Results: MiR-19a expression was significantly downregulated and upregulated in rat neurons and astrocytes, respectively (P < 0.01). A significantly elevated level of miR-19a-3p was found in I/R and OGD models in comparison to sham/control groups (P < 0.01). Expression of the glycolysis enzyme markers LDHA, PKM2, HK2, Glut1 and PDK1, apoptosis-related factors levels, apoptosis, glucose uptake, and lactate production were significantly repressed by both I/R and OGD (P < 0.01 in each case). Moreover, miR-19a-3p mimic aggravated, while miR-19a-3p inhibitor alleviated, the above observations. Adipor2 was predicted and confirmed to be a direct target of miR-19a. Furthermore, restoration of Adipor2 reversed miR-19a-3p-induced effects. Conclusions: Collectively, our results indicate that elevated miR-19a-3p mediates cerebral ischemic injury by targeting ADIPOR2. MiR-19a-3p attenuation thus might offer hope of a novel therapeutic target for ischemic stroke injury treatment.


Assuntos
Apoptose , Isquemia Encefálica/patologia , Glucose/metabolismo , MicroRNAs/metabolismo , Neurônios/metabolismo , Neurônios/patologia , Neuroproteção , Acidente Vascular Cerebral/patologia , Animais , Animais Recém-Nascidos , Astrócitos/metabolismo , Sequência de Bases , Modelos Animais de Doenças , MicroRNAs/genética , Oxigênio , Ratos Sprague-Dawley , Receptores de Adiponectina/metabolismo , Regulação para Cima/genética
16.
Nat Commun ; 10(1): 2505, 2019 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-31175285

RESUMO

Brain signals that govern memory formation remain incompletely identified. The hypothalamus is implicated in memory disorders, but how its rapidly changing activity shapes memorization is unknown. During encounters with objects, hypothalamic melanin-concentrating hormone (MCH) neurons emit brief signals that reflect object novelty. Here we show that targeted optogenetic silencing of these signals, performed selectively during the initial object encounters (i.e. memory acquisition), prevents future recognition of the objects. We identify an upstream inhibitory microcircuit from hypothalamic GAD65 neurons to MCH neurons, which constrains the memory-promoting MCH cell bursts. Finally, we demonstrate that silencing the GAD65 cells during object memory acquisition improves future object recognition through MCH-receptor-dependent pathways. These results provide causal evidence that object-associated signals in genetically distinct but interconnected hypothalamic neurons differentially control whether the brain forms object memories. This gating of memory formation by hypothalamic activity establishes appropriate behavioral responses to novel and familiar objects.


Assuntos
Glutamato Descarboxilase/metabolismo , Hormônios Hipotalâmicos/metabolismo , Hipotálamo/fisiologia , Melaninas/metabolismo , Memória/fisiologia , Neurônios/metabolismo , Hormônios Hipofisários/metabolismo , Receptores do Hormônio Hipofisário/metabolismo , Recognição (Psicologia)/fisiologia , Animais , Hipotálamo/citologia , Hipotálamo/metabolismo , Memória/efeitos dos fármacos , Camundongos , Inibição Neural/fisiologia , Vias Neurais , Optogenética , Piperidinas/farmacologia , Receptores do Hormônio Hipofisário/antagonistas & inibidores , Recognição (Psicologia)/efeitos dos fármacos
17.
Nat Commun ; 10(1): 2746, 2019 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-31227712

RESUMO

Nicotinic acetylcholine receptors (nAChRs) mediate and modulate synaptic transmission throughout the brain, and contribute to learning, memory, and behavior. Dysregulation of α7-type nAChRs in neuropsychiatric as well as immunological and oncological diseases makes them attractive targets for pharmaceutical development. Recently, we identified NACHO as an essential chaperone for α7 nAChRs. Leveraging the robust recombinant expression of α7 nAChRs with NACHO, we utilized genome-wide cDNA library screening and discovered that several anti-apoptotic Bcl-2 family proteins further upregulate receptor assembly and cell surface expression. These effects are mediated by an intracellular motif on α7 that resembles the BH3 binding domain of pro-apoptotic Bcl-2 proteins, and can be blocked by BH3 mimetic Bcl-2 inhibitors. Overexpression of Bcl-2 member Mcl-1 in neurons enhanced surface expression of endogenous α7 nAChRs, while a combination of chemotherapeutic Bcl2-inhibitors suppressed neuronal α7 receptor assembly. These results demonstrate that Bcl-2 proteins link α7 nAChR assembly to cell survival pathways.


Assuntos
Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Neurônios/metabolismo , Receptor Nicotínico de Acetilcolina alfa7/metabolismo , Motivos de Aminoácidos/genética , Animais , Benzotiazóis/farmacologia , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Células HEK293 , Humanos , Isoquinolinas/farmacologia , Chaperonas Moleculares/metabolismo , Mutação , Proteína de Sequência 1 de Leucemia de Células Mieloides/antagonistas & inibidores , Neurônios/efeitos dos fármacos , Agonistas Nicotínicos/farmacologia , Cultura Primária de Células , Ligação Proteica/efeitos dos fármacos , Piridinas/farmacologia , Pirimidinas/farmacologia , Ratos , Transmissão Sináptica/efeitos dos fármacos , Tiofenos/farmacologia , Regulação para Cima , Receptor Nicotínico de Acetilcolina alfa7/genética
18.
Nat Commun ; 10(1): 2394, 2019 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-31160584

RESUMO

To understand the molecular processes that link Aß amyloidosis, tauopathy and neurodegeneration, we screened for tau-interacting proteins by immunoprecipitation/LC-MS. We identified the carboxy-terminal PDZ ligand of nNOS (CAPON) as a novel tau-binding protein. CAPON is an adaptor protein of neuronal nitric oxide synthase (nNOS), and activated by the N-methyl-D-aspartate receptor. We observed accumulation of CAPON in the hippocampal pyramidal cell layer in the AppNL-G-F -knock-in (KI) brain. To investigate the effect of CAPON accumulation on Alzheimer's disease (AD) pathogenesis, CAPON was overexpressed in the brain of AppNL-G-F mice crossbred with MAPT (human tau)-KI mice. This produced significant hippocampal atrophy and caspase3-dependent neuronal cell death in the CAPON-expressing hippocampus, suggesting that CAPON accumulation increases neurodegeneration. CAPON expression also induced significantly higher levels of phosphorylated, oligomerized and insoluble tau. In contrast, CAPON deficiency ameliorated the AD-related pathological phenotypes in tauopathy model. These findings suggest that CAPON could be a druggable AD target.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Doença de Alzheimer/metabolismo , Hipocampo/metabolismo , Agregação Patológica de Proteínas/metabolismo , Células Piramidais/metabolismo , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Precursor de Proteína beta-Amiloide/genética , Animais , Atrofia , Caspase 3/metabolismo , Morte Celular , Cromatografia Líquida , Modelos Animais de Doenças , Técnicas de Introdução de Genes , Hipocampo/patologia , Humanos , Imunoprecipitação , Espectrometria de Massas , Camundongos , Neurônios/metabolismo , Neurônios/patologia , Agregação Patológica de Proteínas/patologia , Células Piramidais/patologia , Tauopatias , Proteínas tau/metabolismo
19.
Nat Commun ; 10(1): 2798, 2019 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-31243268

RESUMO

Dynamic combinatorial chemistry (DCC) has proven its potential in drug discovery speeding the identification of modulators of biological targets. However, the exchange chemistries typically take place under specific reaction conditions, with limited tools capable of operating under physiological parameters. Here we report a catalyzed protein-directed DCC working at low temperatures that allows the calcium sensor NCS-1 to find the best ligands in situ. Ultrafast NMR identifies the reaction intermediates of the acylhydrazone exchange, tracing the molecular assemblies and getting a real-time insight into the essence of DCC processes at physiological pH. Additionally, NMR, X-ray crystallography and computational methods are employed to elucidate structural and mechanistic aspects of the molecular recognition event. The DCC approach leads us to the identification of a compound stabilizing the NCS-1/Ric8a complex and whose therapeutic potential is proven in a Drosophila model of disease with synaptic alterations.


Assuntos
Cálcio/metabolismo , Biblioteca Gênica , Proteínas Sensoras de Cálcio Neuronal/metabolismo , Animais , Catálise , Células Cultivadas , Técnicas de Química Combinatória , Drosophila/fisiologia , Imagem por Ressonância Magnética , Masculino , Membranas Artificiais , Camundongos , Proteínas Sensoras de Cálcio Neuronal/genética , Neurônios/metabolismo , Palmitoil-CoA Hidrolase , Permeabilidade , Conformação Proteica , Proteínas
20.
Chem Biol Interact ; 309: 108686, 2019 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-31152735

RESUMO

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


Assuntos
Acetilcolinesterase/metabolismo , Meios de Cultivo Condicionados/química , Expressão Gênica/efeitos dos fármacos , Dibenzodioxinas Policloradas/farmacologia , Acetilcolinesterase/genética , Animais , Astrócitos/citologia , Astrócitos/metabolismo , Células Cultivadas , Meios de Cultivo Condicionados/farmacologia , Neurônios/citologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Dibenzodioxinas Policloradas/química , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley
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