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1.
Dokl Biochem Biophys ; 486(1): 243-246, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31367831

RESUMO

This work represents one part of our research project, in which we attempted to prove that a humoral regulation between noradrenaline-producing organs exist in the perinatal period. In this study, we used a rat model that allowed blocking the synthesis of noradrenalin in the brain and evaluated gene expression and protein levels of noradrenaline key synthesis enzymes such as tyrosine hydroxylase (TH) and dopamine beta-hydroxylase (DBH) in peripheral noradrenaline-producing organs. As a result, we showed an increased gene expression of TH and DBH in adrenal glands. These data indicate that, if neonatal rat brain lacks the ability to produce noradrenaline, then the synthesis of noradrenaline in adrenal glands increased as a compensatory process, so that the concentration levels in blood are maintained at normal levels. This indicates that there is a humoral regulation between brain and adrenal glands, which is not fully understood yet.


Assuntos
Encéfalo/fisiologia , Morfogênese , Norepinefrina/biossíntese , Animais , Encéfalo/crescimento & desenvolvimento , Dopamina beta-Hidroxilase/genética , Regulação da Expressão Gênica no Desenvolvimento , Ratos , Tirosina 3-Mono-Oxigenase/genética
2.
DNA Cell Biol ; 38(9): 955-961, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31361513

RESUMO

The chromatin-remodeling complex ATRX/DAXX is one of the major epigenetic factors that controls heterochromatin maintenance due to its role in histone deposition. ATRX is involved in nucleosome configuration and maintenance of higher order chromatin structure, and DAXX is a specific histone chaperone for H3.3 deposition. Dysfunctions in this complex have been associated with telomere shortening, which influences cell senescence. However, data about this complex in brain tissue related to aging are still scarce. Therefore, in the present study, we analyzed ATRX and DAXX expressions in autopsied human brain specimens and the telomere length. A significant decrease in gene and protein expressions was observed in the brain tissues from the elderly compared with those from the young, which were related to short telomeres. These findings may motivate further functional analysis to confirm the ATRX-DAXX complex involvement in telomere maintenance and brain aging.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Envelhecimento/genética , Encéfalo/metabolismo , Proteínas Nucleares/genética , Proteína Nuclear Ligada ao X/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Encéfalo/crescimento & desenvolvimento , Humanos , Pessoa de Meia-Idade , Proteínas Nucleares/metabolismo , Homeostase do Telômero , Proteína Nuclear Ligada ao X/metabolismo
3.
Int. j. morphol ; 37(2): 498-503, June 2019. graf
Artigo em Inglês | LILACS | ID: biblio-1002250

RESUMO

A successive embryonic developmental study was conducted on the brain of twenty eight embryos and fetuses of one humped camel (Camelus Dromedarius), whose crown vertebral rump lengths (CVRL) ranged from 9 to 80 mm, collected from the El-Basateen (Cairo) and Belbees (ElSharqya) Slaughterhouse. The current investigation revealed that camel brain was found to consist of fore, mid and hind brains. The fore brain is divided into telencephalon and diencephalon while the rhombencephalon divided into metencephalon and myelencephalon. Flexures appeared between the vesicles are cervical flexure between the rhomencephalon and the spinal cord, cephalic flexure in the mesencephalon and pontine flexure between the metencephalon, and the myelencephalon of the hind brain (rhombencephalon). The cavity of the rhombencephalon is the fourth ventricle, while that of the diencephalon is the third ventricle, and those of the telencephalon are the lateral ventricles but that of mid brain is the cerebral aqueduct. myelencephalon becomes medulla oblongata and metencephalon developed to pons and cerebellum while mesencephalon gives rise to the cerebral crura and anterior and a posterior colliculus. Diencephalon gives the thalamus, hypothalamus, mamillary body, infundibulum and pineal body while telencephalon becomes the cerebral hemispheres and corpus striatum.


Se llevó a cabo un estudio del desarrollo embrionario cerebral de veintiocho embriones y fetos de camello jorobado (Camelus dromedarius). Las muestras fueron recolectadas en los mataderos de El-Basateen (El Cairo) y Belbees (ElSharqya). La investigación reveló que el cerebro de camello posee un cerebro anterior, medio y posterior. El cerebro anterior se divide en telencéfalo y diencéfalo, mientras que el rombencéfalo se divide en metencéfalo y mielencéfalo. Las flexiones encontradas entre las vesículas son la flexión cervical entre el rombencéfalo y la médula espinal; la flexión cefálica en el mesencéfalo; y la flexión pontina entre el metencéfalo y el mielencéfalo del cerebro posterior (rombencéfalo). La cavidad del rombencéfalo conforma el cuarto ventrículo, la del diencéfalo forma el tercer ventrículo, y las del telencéfalo a los ventrículos laterales. En el cerebro medio, la cavidad corresponde al acueducto cerebral. El mielencéfalo se convierte en médula oblonga y el metencéfalo deriva en puente y cerebelo, mientras que el mesencéfalo da lugar a la crura cerebral y a los colículos anterior y posterior. El diencéfalo origina el tálamo, el hipotálamo, el cuerpo mamilar, el infundíbulo y la hipófisis, mientras que del telencéfalo se originan los hemisferios cerebrales y el cuerpo estriado.


Assuntos
Animais , Encéfalo/embriologia , Camelus , Encéfalo/crescimento & desenvolvimento
4.
Rev Med Liege ; 74(5-6): 248-252, 2019 05.
Artigo em Francês | MEDLINE | ID: mdl-31206261

RESUMO

Binge drinking has become a common practice among teenagers, thus a banal behaviour in parties. It is part of a normal psychological evolution that pushes the young to confront limits, prohibitions, other peers, and even more to confront himself. The festive dimension further reinforces this attraction for group transgression. Yet neuroscientific studies are unanimous in showing the negative effects of binge drinking on a maturing brain, with significant neurocognitive and even neuroanatomical alterations. It is illustrated by research conducted on humans and on animal models. This article aims to show the difficult articulation between a clinical practice open to young people and a necessary concern about their behaviour, the danger of which they usually do not know.


Assuntos
Consumo de Bebidas Alcoólicas , Bebedeira , Adolescente , Animais , Encéfalo/crescimento & desenvolvimento , Humanos
5.
J Anim Sci ; 97(7): 3153-3168, 2019 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-31051033

RESUMO

The objective of this study was to assess how exposure to ergot alkaloids during 2 stages of gestation alters fetal growth, muscle fiber formation, and miRNA expression. Pregnant ewes (n = 36; BW = 83.26 ± 8.14 kg; 4/group; 9 groups) were used in a 2 × 2 factorial arrangement with 2 tall fescue seed treatments [endophyte-infected (E+) vs. endophyte-free (E-)] fed during 2 stages of gestation (MID, days 35 to 85 vs. LATE, days 86 to 133), which created 4 possible treatments (E-/E-, E+/E-, E-/E+, or E+/E+). Ewes were individually fed a total mixed ration containing E+ or E- fescue seed according to treatment assignment. Terminal surgeries were conducted on day 133 of gestation for the collection of fetal measurements and muscle samples. Data were analyzed as a 2 × 2 factorial with fescue treatment, stage of gestation, and 2-way interaction as fixed effects. Fetuses exposed to E+ seed during LATE gestation had reduced (P = 0.0020) fetal BW by 10% compared with E- fetuses; however, fetal body weight did not differ (P = 0.41) with E+ exposure during MID gestation. Fetuses from ewes fed E+ seed during MID and LATE gestation tended to have smaller (P = 0.058) kidney weights compared with E- fetuses. Liver weight was larger (P = 0.0069) in fetuses fed E- during LATE gestation compared with E+. Fetal brain weight did not differ by fescue treatment fed during MID (P = 0.36) or LATE (P = 0.40) gestation. The percentage of brain to empty body weight (EBW) was greater (P = 0.0048) in fetuses from ewes fed E+ fescue seed during LATE gestation, which is indicative of intrauterine growth restriction (IUGR). Primary muscle fiber number was lower (P = 0.0005) in semitendinosus (STN) of fetuses exposed to E+ during MID and/or LATE gestation compared with E-/E-. miRNA sequencing showed differential expression (P < 0.010) of 6 novel miRNAs including bta-miR-652_R+1, mdo-miR-22-3p, bta-miR-1277_R-1, ppy-miR-133a_L+1_1ss5TG, hsa-miR-129-1-3p, and ssc-miR-615 in fetal STN muscle. These miRNA are associated with glucose transport, insulin signaling, intracellular ATP, hypertension, or adipogenesis. This work supports the hypothesis that E+ tall fescue seed fed during late gestation reduces fetal weight and causes asymmetrical growth, which is indicative of IUGR. Changes in primary fiber number and miRNA of STN indicate that exposure to E+ fescue fed during MID and LATE gestation alters fetal muscle development that may affect postnatal muscle growth and meat quality.


Assuntos
Endófitos/fisiologia , Alcaloides de Claviceps/toxicidade , Festuca/química , MicroRNAs/genética , Ovinos/fisiologia , Transcriptoma/efeitos dos fármacos , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/crescimento & desenvolvimento , Ergotaminas/toxicidade , Feminino , Festuca/microbiologia , Desenvolvimento Fetal/efeitos dos fármacos , Peso Fetal/efeitos dos fármacos , Fibras Musculares Esqueléticas/efeitos dos fármacos , Placentação , Gravidez , Sementes/química , Sementes/microbiologia , Ovinos/crescimento & desenvolvimento
6.
Gene ; 710: 307-315, 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31125733

RESUMO

FoxL2 is a member of the forkhead/HNF-3-related family of transcription factors which provides tissue specific gene regulation. It is known to regulate ovarian aromatase, which plays a crucial role in ovarian development and mature. To understand the role of FoxL2/ovarian aromatase encoded gene Cyp19a1a during ovarian development and recrudescence, we identified cDNA characteristics of FoxL2 and Cyp19a1a, analyzed its temporal expression both at transcript and protein levels in the anadromous fish, Coilia nasus. Tissue distribution pattern revealed that FoxL2 mRNA expression level was highest in ovary, while Cyp19a1a mRNA was highest in brain. During the upstream migration cycle, in ovary, the FoxL2 mRNA temporal expression peaked at the multiplication stage (stage III in May), the Cyp19a1a mRNA expression peaked at the onset stage (stage I in March). It was found that their mRNA transcripts were maintained at high level during the migration stage (from stage I in March to stage VI in July). Additionally, the strongest immunolabeling positive signals of Cyp19a1a and FoxL2 proteins were mainly found in the cytoplasm of olfactory bulb cell, stratum granulare and neurogliocyte cells and development stage oocytes. Data indicated that FoxL2 and Cyp19a1a were inducible and functional in the C. nasus ovary development and migration process. Therefore, the present results can be regarded as evidence for indispensable roles of FoxL2 and Cyp19a1a in the ovary development and migratory behavior at gene expression patterns and encoded protein distribution level.


Assuntos
Aromatase/metabolismo , Peixes/crescimento & desenvolvimento , Proteína Forkhead Box L2/metabolismo , Ovário/crescimento & desenvolvimento , Animais , Aromatase/genética , Encéfalo/crescimento & desenvolvimento , Encéfalo/metabolismo , Citoplasma/metabolismo , Feminino , Peixes/genética , Peixes/metabolismo , Proteína Forkhead Box L2/genética , Regulação da Expressão Gênica no Desenvolvimento , Ovário/metabolismo , Distribuição Tecidual , Regulação para Cima
7.
Int J Mol Sci ; 20(9)2019 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-31071949

RESUMO

Individuals born preterm have higher rates of neurodevelopmental disorders such as schizophrenia, autistic spectrum, and attention deficit/hyperactivity disorders. These conditions are often sexually dimorphic and with different developmental trajectories. The etiology is likely multifactorial, however, infections both during pregnancy and in childhood have emerged as important risk factors. The association between sex- and age-dependent vulnerability to neuropsychiatric disorders has been suggested to relate to immune activation in the brain, including complex interactions between sex hormones, brain transcriptome, activation of glia cells, and cytokine production. Here, we will review sex-dependent effects on brain development, including glia cells, both under normal physiological conditions and following perinatal inflammation. Emphasis will be given to sex-dependent effects on brain regions which play a role in neuropsychiatric disorders and inflammatory reactions that may underlie early-life programming of neurobehavioral disturbances later in life.


Assuntos
Encéfalo/crescimento & desenvolvimento , Inflamação/fisiopatologia , Transtornos do Neurodesenvolvimento/fisiopatologia , Neuroglia/patologia , Transtorno do Deficit de Atenção com Hiperatividade/fisiopatologia , Transtorno do Espectro Autista/fisiopatologia , Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Humanos , Inflamação/diagnóstico por imagem , Nascimento Prematuro/fisiopatologia , Esquizofrenia/fisiopatologia , Caracteres Sexuais
8.
Hum Genet ; 138(7): 715-721, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31087184

RESUMO

Sequences encoding Olduvai (DUF1220) protein domains show the largest human-specific increase in copy number of any coding region in the genome and have been linked to human brain evolution. Most human-specific copies of Olduvai (119/165) are encoded by three NBPF genes that are adjacent to three human-specific NOTCH2NL genes that have been shown to promote cortical neurogenesis. Here, employing genomic, phylogenetic, and transcriptomic evidence, we show that these NOTCH2NL/NBPF gene pairs evolved jointly, as two-gene units, very recently in human evolution, and are likely co-regulated. Remarkably, while three NOTCH2NL paralogs were added, adjacent Olduvai sequences hyper-amplified, adding 119 human-specific copies. The data suggest that human-specific Olduvai domains and adjacent NOTCH2NL genes may function in a coordinated, complementary fashion to promote neurogenesis and human brain expansion in a dosage-related manner.


Assuntos
Evolução Biológica , Encéfalo/crescimento & desenvolvimento , Encéfalo/metabolismo , Proteínas de Transporte/genética , Genoma Humano , Receptor Notch2/genética , Genômica , Humanos , Filogenia , Domínios Proteicos
9.
Nat Neurosci ; 22(5): 809-819, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30988526

RESUMO

Microscopic features (that is, microstructure) of axons affect neural circuit activity through characteristics such as conduction speed. To what extent axonal microstructure in white matter relates to functional connectivity (synchrony) between brain regions is largely unknown. Using MRI data in 11,354 subjects, we constructed multivariate models that predict functional connectivity of pairs of brain regions from the microstructural signature of white matter pathways that connect them. Microstructure-derived models provided predictions of functional connectivity that explained 3.5% of cross-subject variance on average (ranging from 1-13%, or r = 0.1-0.36) and reached statistical significance in 90% of the brain regions considered. The microstructure-function relationships were associated with genetic variants, co-located with genes DAAM1 and LPAR1, that have previously been linked to neural development. Our results demonstrate that variation in white matter microstructure predicts a fraction of functional connectivity across individuals, and that this relationship is underpinned by genetic variability in certain brain areas.


Assuntos
Encéfalo/anatomia & histologia , Encéfalo/fisiologia , Fenótipo , Substância Branca/anatomia & histologia , Substância Branca/fisiologia , Proteínas Adaptadoras de Transdução de Sinal/genética , Idoso , Encéfalo/crescimento & desenvolvimento , Mapeamento Encefálico , Feminino , Estudo de Associação Genômica Ampla , Humanos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Modelos Neurológicos , Análise Multivariada , Vias Neurais/anatomia & histologia , Vias Neurais/fisiologia , Receptores de Ácidos Lisofosfatídicos/genética
10.
Artigo em Inglês | MEDLINE | ID: mdl-31010095

RESUMO

In this study, several lines of evidence are provided to show that Na + , K + -ATPase activity exerts vital roles in normal brain development and function and that loss of enzyme activity is implicated in neurodevelopmental, neuropsychiatric and neurodegenerative disorders, as well as increased risk of cancer, metabolic, pulmonary and cardiovascular disease. Evidence is presented to show that fluoride (F) inhibits Na + , K + -ATPase activity by altering biological pathways through modifying the expression of genes and the activity of glycolytic enzymes, metalloenzymes, hormones, proteins, neuropeptides and cytokines, as well as biological interface interactions that rely on the bioavailability of chemical elements magnesium and manganese to modulate ATP and Na + , K + -ATPase enzyme activity. Taken together, the findings of this study provide unprecedented insights into the molecular mechanisms and biological pathways by which F inhibits Na + , K + -ATPase activity and contributes to the etiology and pathophysiology of diseases associated with impairment of this essential enzyme. Moreover, the findings of this study further suggest that there are windows of susceptibility over the life course where chronic F exposure in pregnancy and early infancy may impair Na + , K + -ATPase activity with both short- and long-term implications for disease and inequalities in health. These findings would warrant considerable attention and potential intervention, not to mention additional research on the potential effects of F intake in contributing to chronic disease.


Assuntos
Fluoretos/farmacologia , Saúde Pública , ATPase Trocadora de Sódio-Potássio/metabolismo , Animais , Encéfalo/enzimologia , Encéfalo/crescimento & desenvolvimento , Exposição Ambiental , Fluoretos/metabolismo , Humanos , Minerais/metabolismo
11.
Zool Res ; 40(3): 236-238, 2019 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-31011135

RESUMO

Why humans have large brains with higher cognitive abilities is a question long asked by scientists. However, much remains unknown, especially the underlying genetic mechanisms. With the use of a transgenic monkey model, we showed that human-specific sequence changes of a key brain development gene (primary microcephaly1, MCPH1) could result in detectable molecular and cognitive changes resembling human neoteny, a notable characteristic developed during human evolution.


Assuntos
Encéfalo/crescimento & desenvolvimento , Haplorrinos/genética , Haplorrinos/fisiologia , Proteínas do Tecido Nervoso/metabolismo , Animais , Animais Geneticamente Modificados , Evolução Biológica , Humanos
12.
Chem Biol Interact ; 305: 3-10, 2019 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-30890323

RESUMO

The neurotoxic environmental contaminant, methylmercury (MeHg), has shown to have detrimental effects on the developing brain when exposed during gestation. We have shown in our earlier studies that gestational administration of 3,3',4',7-Tetrahydroxyflavone or Fisetin reduces the toxic effects of MeHg in the developing rat brain. The current study has pivoted to study the mechanism behind the mitigating action of Fisetin against prenatal MeHg exposure induced neurotoxicity. Negligible data is available about the toxicity targets of MeHg in the developing brain. Studies have exhibited that MeHg exposure cause toxic effects on synaptic transmission and plasticity in the offspring brain. Hence, we aimed to study the effect of Fisetin on MeHg induced alterations in the expressions of regulatory genes and proteins involved in synaptic plasticity and transmission. Pregnant rats were grouped according to the type of oral administration as, (i) Control, (ii) MeHg (1.5 mg/kg b. w.), (iii) MeHg + Fisetin (30 mg/kg b. w.) and (iv) Fisetin (30 mg/kg b. w). Maternal administration of Fisetin prevented MeHg exposure induced downregulation of neurogranin (Nrgn), dendrin (Ddn), Syntaxin 1 A (Stx1a), Lin-7 homolog A (Lin7a), Complexin-2 (Cplx2) and Exocyst complex component 8 (Exoc8) genes in the offspring rat. Fisetin also prevented MeHg exposure induced downregulation of brain derived neurotrophic factor (BDNF), Glial-cell derived neurotrophic factor (GDNF) protein expressions and hampered reactive astrogliosis in the hippocampus of F1 generation rats. Hence, through this study, we conclude that Fisetin modulates the expression of regulatory genes and proteins involved in synaptic transmission and plasticity and extenuates MeHg neurotoxicity in the developing rat brain.


Assuntos
Flavonoides/farmacologia , Hipocampo/metabolismo , Compostos de Metilmercúrio/toxicidade , Plasticidade Neuronal/efeitos dos fármacos , Transmissão Sináptica/efeitos dos fármacos , Administração Oral , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/crescimento & desenvolvimento , Encéfalo/metabolismo , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Regulação para Baixo/efeitos dos fármacos , Feminino , Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Exposição Materna , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Neurogranina/genética , Neurogranina/metabolismo , Gravidez , Ratos , Ratos Wistar
13.
J Mol Neurosci ; 68(1): 58-65, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30847723

RESUMO

Prolonged or repeated exposure to ketamine, a common anesthetic in pediatrics, has been shown to induce neurotoxicity and long-term neurocognitive deficits in the developing brain. Therefore, identification of potential therapeutic targets for preventing or alleviating such neurodegeneration and neuroapoptosis induced by ketamine is urgently needed. Remote ischemic preconditioning of the limb provides neuroprotection in different models of cerebral injury. Thus, the present study aimed to assess whether remote ischemic preconditioning could have a neuroprotective effect against neurotoxicity induced by ketamine. In our study, 96 newborn rats were assigned to one of four groups, including control, remote ischemic preconditioning, ketamine, and remote ischemic preconditioning plus ketamine. Ketamine was administered intraperitoneally in six doses of 20 mg/kg at 2-h intervals. Limb remote ischemic preconditioning comprised four ischemia (5 min)/reperfusion (5 min) cycles in the right hind limb using an elastic rubber band tourniquet. Histopathological characteristics of cerebral damage were assessed by H&E staining and transmission electron microscopy. TUNEL assay, immunohistochemical staining and immunoblot were employed to evaluate neural cell apoptosis. Learning and memory were evaluated using the Morris water maze. The results showed increased cleaved caspase-3 protein levels in the cerebral cortex and the hippocampal CA1 region, severe cell damage and DNA breakage, and decreased spatial learning and memory abilities in the ketamine group in comparison with controls. Notably, these changes were significantly reduced by remote ischemic preconditioning. These findings suggest that remote ischemic preconditioning ameliorates neuroapoptosis and neurocognitive impairment after repeated ketamine exposure in newborn rats.


Assuntos
Anestésicos Dissociativos/efeitos adversos , Encéfalo/efeitos dos fármacos , Transtornos Cognitivos/prevenção & controle , Extremidades/irrigação sanguínea , Precondicionamento Isquêmico/métodos , Ketamina/efeitos adversos , Animais , Apoptose , Encéfalo/crescimento & desenvolvimento , Transtornos Cognitivos/etiologia , Aprendizagem em Labirinto , Ratos , Ratos Sprague-Dawley
14.
Curr Protoc Neurosci ; 87(1): e65, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30861320

RESUMO

Interneurons in the olfactory bulb are generated from neuronal precursor cells migrating from the anterior subventricular zone (SVZa) throughout the embryonic and postnatal life of mammals. This article describes basic methods for in vivo electroporation to label SVZa cells of both embryonic and postnatal rats. In addition, it describes three methods for tracing SVZa progenitors and following their migration pathway and differentiation, including immunohistochemistry, time-lapse live imaging in slice culture, and time-lapse imaging following transplantation in slice culture. These methods may be applied to all strains of rats and mice, including reporter mice. They may also be combined with methods such as BrdU labeling, tamoxifen injection, and electrophysiology, allowing one to observe proliferation or control gene expression at specific times and for specific neuronal functions. With time-lapse live imaging, details of labeled cells can be studied, including morphology, motility pattern, differentiation, and crosstalk between cells. © 2019 by John Wiley & Sons, Inc.


Assuntos
Encéfalo/fisiologia , Diferenciação Celular/fisiologia , Eletroporação , Imagem com Lapso de Tempo , Animais , Animais Recém-Nascidos , Encéfalo/crescimento & desenvolvimento , Movimento Celular/fisiologia , Eletroporação/métodos , Interneurônios/fisiologia , Camundongos , Neurônios/fisiologia , Ratos , Células-Tronco/citologia , Imagem com Lapso de Tempo/métodos
15.
BMC Neurosci ; 20(1): 8, 2019 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-30832562

RESUMO

BACKGROUND: The electroencephalogram (EEG) is a widely used laboratory technique in rodent models of epilepsy, traumatic brain injury (TBI), and other neurological diseases accompanied by seizures. Obtaining prolonged continuous EEG tracings over weeks to months is essential to adequately answer research questions related to the chronobiology of seizure emergence, and to the effect of potential novel treatment strategies. Current EEG recording methods include wired and the more recent but very costly wireless technologies. Wired continuous long-term EEG in rodents remains the mainstay approach but is often technically challenging due to the notorious frequent EEG cable disconnections from the rodent's head, and to poor signal-to-noise ratio especially when simultaneously monitoring multiple animals. Premature EEG cable disconnections and cable movement-related artifacts result from the animal's natural mobility, and subsequent tension on the EEG wires, as well as from potential vigorous and frequent seizures. These challenges are often accompanied by injuries to the scalp, and result in early terminations of costly experiments. RESULTS: Here we describe an enhanced customized swivel-balance EEG-cage system that allows tension-free rat mobility. The cage setup markedly improves the safety and longevity of current existing wired continuous long-term EEG. Prevention of EEG cable detachments is further enhanced by a special attention to surgical electrode anchoring to the skull. In addition to mechanically preventing premature disconnections, the detailed stepwise approach to the electrical shielding, wiring and grounding required for artifact-free high signal-to-noise ratio recordings is also included. The successful application of our EEG cage system in various rat models of brain insults and epilepsy is described with illustrative high quality tracings of seizures and electrographic patterns obtained during continuous and simultaneous monitoring of multiple rats early and up to 3 months post-brain insult. CONCLUSION: Our simple-to-implement key modifications to the EEG cage setup allow the safe acquisition of substantial high quality wired EEG data without resorting to the still costly wireless technologies.


Assuntos
Eletroencefalografia/instrumentação , Modelos Animais , Animais , Encéfalo/crescimento & desenvolvimento , Encéfalo/fisiopatologia , Eletrodos Implantados , Epilepsia/fisiopatologia , Desenho de Equipamento , Abrigo para Animais , Masculino , Movimento , Ratos , Ratos Sprague-Dawley , Convulsões/fisiopatologia
16.
Proc Natl Acad Sci U S A ; 116(14): 7101-7106, 2019 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-30886094

RESUMO

The development of complex cognitive functions during human evolution coincides with pronounced encephalization and expansion of white matter, the brain's infrastructure for region-to-region communication. We investigated adaptations of the human macroscale brain network by comparing human brain wiring with that of the chimpanzee, one of our closest living primate relatives. White matter connectivity networks were reconstructed using diffusion-weighted MRI in humans (n = 57) and chimpanzees (n = 20) and then analyzed using network neuroscience tools. We demonstrate higher network centrality of connections linking multimodal association areas in humans compared with chimpanzees, together with a more pronounced modular topology of the human connectome. Furthermore, connections observed in humans but not in chimpanzees particularly link multimodal areas of the temporal, lateral parietal, and inferior frontal cortices, including tracts important for language processing. Network analysis demonstrates a particularly high contribution of these connections to global network integration in the human brain. Taken together, our comparative connectome findings suggest an evolutionary shift in the human brain toward investment of neural resources in multimodal connectivity facilitating neural integration, combined with an increase in language-related connectivity supporting functional specialization.


Assuntos
Encéfalo/crescimento & desenvolvimento , Encéfalo/fisiologia , Imagem Multimodal/métodos , Adulto , Idoso , Animais , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Cognição , Conectoma/métodos , Imagem de Difusão por Ressonância Magnética/métodos , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Linguagem , Pessoa de Meia-Idade , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/crescimento & desenvolvimento , Rede Nervosa/fisiologia , Pan troglodytes , Substância Branca/diagnóstico por imagem , Substância Branca/crescimento & desenvolvimento , Adulto Jovem
18.
Int J Mol Sci ; 20(6)2019 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-30875831

RESUMO

For the past few years there has been an exponential increase in the use of animal models to confirm the pathogenicity of candidate disease-causing genetic variants found in patients. One such animal model is the zebrafish. Despite being a non-mammalian animal, the zebrafish model has proven its potential in recapitulating the phenotypes of many different human genetic disorders. This review will focus on recent advances in the modeling of neurodevelopmental disorders in zebrafish, covering aspects from early brain development to techniques used for modulating gene expression, as well as how to best characterize the resulting phenotypes. We also review other existing models of neurodevelopmental disorders, and the current efforts in developing and testing compounds with potential therapeutic value.


Assuntos
Transtornos do Neurodesenvolvimento/patologia , Peixe-Zebra , Animais , Encéfalo/crescimento & desenvolvimento , Encéfalo/patologia , Modelos Animais de Doenças , Predisposição Genética para Doença , Humanos , Transtornos do Neurodesenvolvimento/genética , Fenótipo
19.
Int J Mol Sci ; 20(4)2019 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-30795555

RESUMO

As part of the blood-brain-barrier, astrocytes are ideally positioned between cerebral vasculature and neuronal synapses to mediate nutrient uptake from the systemic circulation. In addition, astrocytes have a robust enzymatic capacity of glycolysis, glycogenesis and lipid metabolism, managing nutrient support in the brain parenchyma for neuronal consumption. Here, we review the plasticity of astrocyte energy metabolism under physiologic and pathologic conditions, highlighting age-dependent brain dysfunctions. In astrocytes, glycolysis and glycogenesis are regulated by noradrenaline and insulin, respectively, while mitochondrial ATP production and fatty acid oxidation are influenced by the thyroid hormone. These regulations are essential for maintaining normal brain activities, and impairments of these processes may lead to neurodegeneration and cognitive decline. Metabolic plasticity is also associated with (re)activation of astrocytes, a process associated with pathologic events. It is likely that the recently described neurodegenerative and neuroprotective subpopulations of reactive astrocytes metabolize distinct energy substrates, and that this preference is supposed to explain some of their impacts on pathologic processes. Importantly, physiologic and pathologic properties of astrocytic metabolic plasticity bear translational potential in defining new potential diagnostic biomarkers and novel therapeutic targets to mitigate neurodegeneration and age-related brain dysfunctions.


Assuntos
Adaptação Fisiológica , Envelhecimento/metabolismo , Astrócitos/metabolismo , Encéfalo/metabolismo , Metabolismo Energético , Animais , Encéfalo/crescimento & desenvolvimento , Humanos
20.
J Neurosurg Anesthesiol ; 31(1): 119-121, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30767934

RESUMO

Neuroimaging has been increasingly used as a modality to study the impact of pain, analgesia, and anesthetics on pediatric neurodevelopment. The sixth biennial Pediatric Anesthesia Neurodevelopmental Assessment (PANDA) Symposium addressed the 2016 US Food and Drug Administration drug safety warning regarding the potential neurotoxic effects of commonly used anesthetic and sedative medications in children, and included a session discussing the use of various neuroimaging techniques, to detect structural, metabolic, and functional brain changes that can occur with exposure to pain and to anesthetic medications. The presenters concluded that advanced multimodal magnetic resonance imaging techniques are useful in detecting the aforementioned changes, which were found to be pain-specific and anesthetic agent-specific.


Assuntos
Analgesia , Anestesia/efeitos adversos , Anestésicos/efeitos adversos , Encéfalo/efeitos dos fármacos , Encéfalo/crescimento & desenvolvimento , Neuroimagem/métodos , Dor/diagnóstico por imagem , Adolescente , Biomarcadores , Encéfalo/patologia , Criança , Pré-Escolar , Humanos , Lactente , Recém-Nascido , Dor/patologia , Manejo da Dor
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