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1.
Proc Biol Sci ; 287(1929): 20200239, 2020 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-32576103

RESUMO

Animals display remarkable variation in social behaviour. However, outside of rodents, little is known about the neural mechanisms of social variation, and whether they are shared across species and sexes, limiting our understanding of how sociality evolves. Using coral reef butterflyfishes, we examined gene expression correlates of social variation (i.e. pair bonding versus solitary living) within and between species and sexes. In several brain regions, we quantified gene expression of receptors important for social variation in mammals: oxytocin (OTR), arginine vasopressin (V1aR), dopamine (D1R, D2R) and mu-opioid (MOR). We found that social variation across individuals of the oval butterflyfish, Chaetodon lunulatus, is linked to differences in OTR,V1aR, D1R, D2R and MOR gene expression within several forebrain regions in a sexually dimorphic manner. However, this contrasted with social variation among six species representing a single evolutionary transition from pair-bonded to solitary living. Here, OTR expression within the supracommissural part of the ventral telencephalon was higher in pair-bonded than solitary species, specifically in males. These results contribute to the emerging idea that nonapeptide, dopamine and opioid signalling is a central theme to the evolution of sociality across individuals, although the precise mechanism may be flexible across sexes and species.


Assuntos
Expressão Gênica , Perciformes/fisiologia , Comportamento Social , Animais , Recifes de Corais , Perciformes/genética , Telencéfalo , Vasopressinas
2.
PLoS Biol ; 18(5): e3000705, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32401820

RESUMO

Modeling the processes of neuronal progenitor proliferation and differentiation to produce mature cortical neuron subtypes is essential for the study of human brain development and the search for potential cell therapies. We demonstrated a novel paradigm for the generation of vascularized organoids (vOrganoids) consisting of typical human cortical cell types and a vascular structure for over 200 days as a vascularized and functional brain organoid model. The observation of spontaneous excitatory postsynaptic currents (sEPSCs), spontaneous inhibitory postsynaptic currents (sIPSCs), and bidirectional electrical transmission indicated the presence of chemical and electrical synapses in vOrganoids. More importantly, single-cell RNA-sequencing analysis illustrated that vOrganoids exhibited robust neurogenesis and that cells of vOrganoids differentially expressed genes (DEGs) related to blood vessel morphogenesis. The transplantation of vOrganoids into the mouse S1 cortex resulted in the construction of functional human-mouse blood vessels in the grafts that promoted cell survival in the grafts. This vOrganoid culture method could not only serve as a model to study human cortical development and explore brain disease pathology but also provide potential prospects for new cell therapies for nervous system disorders and injury.


Assuntos
Técnicas de Cultura de Células , Neurogênese , Organoides/irrigação sanguínea , Telencéfalo/embriologia , Animais , Células-Tronco Embrionárias , Células Endoteliais da Veia Umbilical Humana , Humanos , Células-Tronco Pluripotentes Induzidas , Camundongos Endogâmicos NOD , Camundongos SCID , Organoides/metabolismo , Organoides/transplante
3.
Nat Methods ; 17(6): 605-608, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32341543

RESUMO

Behaviors emerge from activity throughout the brain, but noninvasive optical access in adult vertebrate brains is limited. We show that three-photon (3P) imaging through the head of intact adult zebrafish allows structural and functional imaging at cellular resolution throughout the telencephalon and deep into the cerebellum and optic tectum. With 3P imaging, considerable portions of the brain become noninvasively accessible from embryo to sexually mature adult in a vertebrate model.


Assuntos
Cerebelo/diagnóstico por imagem , Imageamento Tridimensional/métodos , Fótons , Colículos Superiores/diagnóstico por imagem , Telencéfalo/diagnóstico por imagem , Peixe-Zebra/anatomia & histologia , Animais
4.
Int. j. morphol ; 38(2): 499-504, abr. 2020. graf
Artigo em Inglês | LILACS | ID: biblio-1056468

RESUMO

Several studies on the elasmobranchs neuroanatomy have shown that their brain is more complex than previously thought, and had significant intra and interspecific variations. The objective of this work was conducting a comparative encephalic neuroanatomy study of two species of genus Myliobatis. In total, 16 organisms of genera Myliobatis californica and Myliobatis longirostris, collected in the coasts of Kino Bay, Sonora, Mexico, were used. In Myliobatis, the brain has a long telencephalon and the posterior central nucleus is poorly developed. Their cerebellum is asymmetric, has several sulci, most of which are transversally oriented, with four lobes (anterior, medium and two posterior), a condition which has not been reported for any other species. It was observed that, despite the morphology of M. californica and M. longirostris is similar, there are some significant differences. Both species have moderate foliation, but M. californica has more sulci. In the diencephalon of M. californica, it was observed that the lobes of the infundibulum are oval-shaped and separated, while in M. longirostris, such lobes are rounded and near the medium line. It has to be highlighted that Myliobatis belongs to the most derived batoid group; nevertheless, its brain is considerably less complex, as compared to what has been reported for the most derived milyobatoids species.


Diversos estudios sobre la neuroanatomía de los elasmobranquios han demostrado que el cerebro es más complejo de lo que se pensaba y presenta considerables variaciones tanto intra como interespecíficas. El objetivo de este trabajo fue realizar un estudio de neuroanatomía comparada del encéfalo de dos especies del género Myliobatis. Se utilizaron un total de 16 organismos de Myliobatis californica y Myliobatis longirostris, los cuales fueron colectados en las costas de Bahía Kino, Son., México. El cerebro de Myliobatis tiene un telencéfalo largo, el núcleo central posterior está poco desarrollado; el cerebelo es asimétrico, presenta surcos que en su mayoría están orientados transversalmente, con cuatro lóbulos (anterior, medio y dos posteriores), condición que no ha sido reportada para otra especie. Se observó que, aunque M. californica y M. longirostris presentan una morfología similar existen ciertas diferencias. En ambas especies presentan una foliación moderada; sin embargo, en M. californica se observan más surcos. En el diencéfalo de M. californica se observa que los lóbulos del infundíbulo son ovalados y están separados, mientras que en M. longirostris son redondeados y se encuentran próximos a la línea media. Es importante señalar que, pese a que Myliobatis pertenece al grupo de batoideos más derivado, su cerebro es considerablemente menos complejo de lo que se ha reportado para las especies de miliobatoideos más derivadas.


Assuntos
Animais , Rajidae/anatomia & histologia , Encéfalo/anatomia & histologia , Telencéfalo/anatomia & histologia , Cerebelo/anatomia & histologia
5.
Nat Commun ; 11(1): 1172, 2020 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-32127543

RESUMO

von Economo neurons (VENs) are bipolar, spindle-shaped neurons restricted to layer 5 of human frontoinsula and anterior cingulate cortex that appear to be selectively vulnerable to neuropsychiatric and neurodegenerative diseases, although little is known about other VEN cellular phenotypes. Single nucleus RNA-sequencing of frontoinsula layer 5 identifies a transcriptomically-defined cell cluster that contained VENs, but also fork cells and a subset of pyramidal neurons. Cross-species alignment of this cell cluster with a well-annotated mouse classification shows strong homology to extratelencephalic (ET) excitatory neurons that project to subcerebral targets. This cluster also shows strong homology to a putative ET cluster in human temporal cortex, but with a strikingly specific regional signature. Together these results suggest that VENs are a regionally distinctive type of ET neuron. Additionally, we describe the first patch clamp recordings of VENs from neurosurgically-resected tissue that show distinctive intrinsic membrane properties relative to neighboring pyramidal neurons.


Assuntos
Neurônios/fisiologia , Lobo Temporal/citologia , Transcriptoma , Animais , Encéfalo/citologia , Encéfalo/fisiologia , Eletrofisiologia/métodos , Perfilação da Expressão Gênica , Humanos , Hibridização in Situ Fluorescente , Camundongos , Neurônios/citologia , Células Piramidais/fisiologia , Telencéfalo/citologia , Lobo Temporal/fisiologia
6.
Nat Commun ; 11(1): 686, 2020 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-32019934

RESUMO

Humans' symbolic counting skills are built on a primordial ability to approximately estimate the number of items, or numerosity. To date it is debated whether numerosities presented in categorically different formats, that is as temporal sequences versus spatial arrays, are represented abstractly in the brain. To address this issue, we identified the behavioral characteristics and neuronal codes for sequential and simultaneous number formats in crows. We find a format-dependent representation by distinct groups of selective neurons during the sensory encoding stage. However, an abstract and format-independent numerosity code emerges once the encoding phase is completed and numerosities needed to be memorized. These results suggest a successive two-stage code for categorically different number formats and help to reconcile conflicting findings observed in psychophysics and brain imaging.


Assuntos
Corvos/fisiologia , Telencéfalo/fisiologia , Animais , Masculino , Conceitos Matemáticos , Neurônios/fisiologia , Percepção Visual
7.
Mol Cells ; 43(1): 76-85, 2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-31910335

RESUMO

MARCH5 is a RING finger E3 ligase involved in mitochondrial integrity, cellular protein homeostasis, and the regulation of mitochondrial fusion and fission. To determine the function of MARCH5 during development, we assessed transcript expression in zebrafish embryos. We found that march5 transcripts were of maternal origin and evenly distributed at the 1-cell stage, except for the mid-blastula transition, with expression predominantly in the developing central nervous system at later stages of embryogenesis. Overexpression of march5 impaired convergent extension movement during gastrulation, resulting in reduced patterning along the dorsoventral axis and alterations in the ventral cell types. Overexpression and knockdown of march5 disrupted the organization of the developing telencephalon and diencephalon. Lastly, we found that the transcription of march5 was tightly regulated by the transcriptional regulators CHOP, C/EBPα, Staf, Znf143a, and Znf76. These results demonstrate the essential role of March5 in the development of zebrafish embryos.


Assuntos
Sistema Nervoso Central/fisiologia , Diencéfalo/embriologia , Proteínas de Membrana/metabolismo , Mitocôndrias/metabolismo , Telencéfalo/embriologia , Ubiquitina-Proteína Ligases/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Peixe-Zebra/embriologia , Animais , Desenvolvimento Embrionário , Técnicas de Silenciamento de Genes , Células HEK293 , Homeostase , Humanos , Proteínas de Membrana/genética , Ubiquitina-Proteína Ligases/genética , Ubiquitinação , Proteínas de Peixe-Zebra/genética
8.
Development ; 147(1)2020 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-31908317

RESUMO

Zebrafish display widespread and pronounced adult neurogenesis, which is fundamental for their regeneration capability after central nervous system injury. However, the cellular identity and the biological properties of adult newborn neurons are elusive for most brain areas. Here, we have used short-term lineage tracing of radial glia progeny to prospectively isolate newborn neurons from the her4.1+ radial glia lineage in the homeostatic adult forebrain. Transcriptome analysis of radial glia, newborn neurons and mature neurons using single cell sequencing identified distinct transcriptional profiles, including novel markers for each population. Specifically, we detected two separate newborn neuron types, which showed diversity of cell fate commitment and location. Further analyses showed that these cell types are homologous to neurogenic cells in the mammalian brain, identified neurogenic commitment in proliferating radial glia and indicated that glutamatergic projection neurons are generated in the adult zebrafish telencephalon. Thus, we prospectively isolated adult newborn neurons from the adult zebrafish forebrain, identified markers for newborn and mature neurons in the adult brain, and revealed intrinsic heterogeneity among adult newborn neurons and their homology with mammalian adult neurogenic cell types.


Assuntos
Encéfalo/citologia , Linhagem da Célula , Células Ependimogliais/citologia , Neurogênese , Neurônios/citologia , Peixe-Zebra/anatomia & histologia , Animais , Animais Geneticamente Modificados , Animais Recém-Nascidos/anatomia & histologia , Diencéfalo/citologia , Perfilação da Expressão Gênica , Camundongos , Análise de Sequência de RNA , Análise de Célula Única , Telencéfalo/citologia , Peixe-Zebra/crescimento & desenvolvimento
9.
J Vis Exp ; (153)2019 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-31840665

RESUMO

The neural mechanisms governing fish behavior remain mostly unknown, although fish constitute the majority of all vertebrates. The ability to record brain activity from freely moving fish would advance research on the neural basis of fish behavior considerably. Moreover, precise control of the recording location in the brain is critical to studying coordinated neural activity across regions in fish brain. Here, we present a technique that records wirelessly from the brain of freely swimming fish while controlling for the depth of the recording location. The system is based on a neural logger associated with a novel water-compatible implant that can adjust the recording location by microdrive-controlled tetrodes. The capabilities of the system are illustrated through recordings from the telencephalon of goldfish.


Assuntos
Eletrodos Implantados , Eletroencefalografia/instrumentação , Eletroencefalografia/métodos , Neurônios/fisiologia , Natação/fisiologia , Animais , Mapeamento Encefálico , Carpa Dourada/fisiologia , Telencéfalo/citologia , Telencéfalo/fisiologia
10.
Nat Commun ; 10(1): 4911, 2019 10 29.
Artigo em Inglês | MEDLINE | ID: mdl-31664020

RESUMO

Foxg constitutes a regulatory loop with Fgf8 and plays an important role in the development of anterior placodes and the telencephalon in vertebrate embryos. Ascidians, which belong to Tunicata, the sister group of vertebrates, develop a primitive placode-like structure at the anterior boundary of the neural plate, but lack a clear counterpart of the telencephalon. In this animal, Foxg is expressed in larval palps, which are adhesive organs with sensory neurons. Here, we show that Foxg begins to be expressed in two separate rows of cells within the neural plate boundary region under the control of the MAPK pathway to pattern this region. However, Foxg is not expressed in the brain, and we find no evidence that knockdown of Foxg affects brain formation. Our data suggest that recruitment of Fgf to the downstream of Foxg might have been a critical evolutionary event for the telencephalon in the vertebrate lineage.


Assuntos
Crista Neural/metabolismo , Células Receptoras Sensoriais/metabolismo , Fatores de Transcrição/metabolismo , Urocordados/embriologia , Animais , Evolução Biológica , Regulação da Expressão Gênica no Desenvolvimento , Crista Neural/citologia , Crista Neural/embriologia , Telencéfalo/embriologia , Telencéfalo/metabolismo , Fatores de Transcrição/genética , Urocordados/citologia , Urocordados/metabolismo
11.
Gene Expr Patterns ; 34: 119073, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31574305

RESUMO

FoxG1, a member of the Fox/Forkhead family of winged helix transcription factors, plays key roles in the induction and spatial compartmentalization of the telencephalon in vertebrates. Loss- and gain-of-function experiments have established FoxG1 as a maintenance factor for neural progenitors and a crucial player in the specification of the ventral telencephalon (subpallium). For the first time in evolution, the telencephalon appeared in the ancestors of vertebrates, including cyclostomes. However, although FoxG1 homologues are present in cyclostomes (i.e., in lampreys and hagfishes), no systematic study of the spatial-temporal expression of FoxG1 during the embryonic development of these animals has been carried out. Given these findings, we have now studied FoxG1 spatial-temporal expression patterns in the early development of the European river lamprey Lampetra fluviatilis. We show that in contrast to other vertebrates, in which the expression of FoxG1 begins during neurulation, the expression of this gene in L. fluviatilis starts after neurulation, first at stage 21 (early head protrusion) in the area of the otic placodes and then, beginning from stage 22, in the telencephalon. Such heterochrony of FoxG1 expression in the lamprey may reflect the fact that in this basally divergent representative of vertebrates, telencephalon specification occurs relatively late. This heterochrony could be related to the evolutionary history of the telencephalon, with a recent appearance in vertebrates as an extension to more ancient anterior brain regions. Another peculiarity of FoxG1 expression in lamprey, compared to other vertebrates, is that it is not expressed in the lamprey optic structures.


Assuntos
Desenvolvimento Embrionário/genética , Lampreias/embriologia , Lampreias/genética , Animais , Encéfalo/metabolismo , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/genética , Lampreias/metabolismo , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Telencéfalo/metabolismo , Vertebrados/metabolismo
12.
Nat Biotechnol ; 37(10): 1198-1208, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31501559

RESUMO

Harnessing the potential of human embryonic stem cells to mimic normal and aberrant development with standardized models is a pressing challenge. Here we use micropattern technology to recapitulate early human neurulation in large numbers of nearly identical structures called neuruloids. Dual-SMAD inhibition followed by bone morphogenic protein 4 stimulation induced self-organization of neuruloids harboring neural progenitors, neural crest, sensory placode and epidermis. Single-cell transcriptomics unveiled the precise identities and timing of fate specification. Investigation of the molecular mechanism of neuruloid self-organization revealed a pulse of pSMAD1 at the edge that induced epidermis, whose juxtaposition to central neural fates specifies neural crest and placodes, modulated by fibroblast growth factor and Wnt. Neuruloids provide a unique opportunity to study the developmental aspects of human diseases. Using isogenic Huntington's disease human embryonic stem cells and deep neural network analysis, we show how specific phenotypic signatures arise in our model of early human development as a consequence of mutant huntingtin protein, outlining an approach for phenotypic drug screening.


Assuntos
Ectoderma/fisiologia , Células-Tronco Embrionárias/fisiologia , Doença de Huntington , Neurulação/fisiologia , Telencéfalo/crescimento & desenvolvimento , Técnicas de Cultura de Células , Diferenciação Celular/fisiologia , Linhagem Celular , Humanos , Neurogênese , Telencéfalo/fisiologia
13.
Dev Neurobiol ; 79(8): 794-804, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31509642

RESUMO

In adult songbirds, the telencephalic song nucleus HVC and its efferent target RA undergo pronounced seasonal changes in morphology. In breeding birds, there are increases in HVC volume and total neuron number, and RA neuronal soma area compared to nonbreeding birds. At the end of breeding, HVC neurons die through caspase-dependent apoptosis and thus, RA neuron size decreases. Changes in HVC and RA are driven by seasonal changes in circulating testosterone (T) levels. Infusing T, or its metabolites 5α-dihydrotestosterone (DHT) and 17 ß-estradiol (E2), intracerebrally into HVC (but not RA) protects HVC neurons from death, and RA neuron size, in nonbreeding birds. The phosphoinositide 3-kinase (PI3K)-Akt (a serine/threonine kinase)-mechanistic target of rapamycin (mTOR) signaling pathway is a point of convergence for neuroprotective effects of sex steroids and other trophic factors. We asked if mTOR activation is necessary for the protective effect of hormones in HVC and RA of adult male Gambel's white-crowned sparrows (Zonotrichia leucophrys gambelii). We transferred sparrows from breeding to nonbreeding hormonal and photoperiod conditions to induce regression of HVC neurons by cell death and decrease of RA neuron size. We infused either DHT + E2, DHT + E2 plus the mTOR inhibitor rapamycin, or vehicle alone in HVC. Infusion of DHT + E2 protected both HVC and RA neurons. Coinfusion of rapamycin with DHT + E2, however, blocked the protective effect of hormones on HVC volume and neuron number, and RA neuron size. These results suggest that activation of mTOR is an essential downstream step in the neuroprotective cascade initiated by sex steroid hormones in the forebrain.


Assuntos
Plasticidade Neuronal/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Sirolimo/farmacologia , Vocalização Animal/efeitos dos fármacos , Envelhecimento , Animais , Di-Hidrotestosterona/farmacologia , Estrogênios/farmacologia , Plasticidade Neuronal/fisiologia , Neurônios/fisiologia , Pardais/fisiologia , Telencéfalo/efeitos dos fármacos , Testosterona/farmacologia , Vocalização Animal/fisiologia
14.
Int. j. morphol ; 37(3): 1172-1178, Sept. 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1012413

RESUMO

The morphological and histological structure of the brains of Bufo gargarizans and Cynops orientalis were observed by anatomy and light microscopy. The results show that the brains of Bufo gargarizans and Cynops orientalis are divided into 5 parts which include the telencephalon, diencephalon, mesencephalon, cerebellum and medulla oblongata. The telencephalon consists of the olfactory bulb and the cerebral hemisphere. The olfactory bulb is developed that has two pairs of olfactory nerve. Bufo gargarizan has a symmetrical oval hemisphere optic lobes; Cynops orientalis only has a spherical optic lobe. The cerebellum is situated behind the optic lobe and closely connected with the myelencephalon. In this paper, the morphological and histological differences between the two species are discussed. The proportion of cerebral hemisphere is gradually increasing, which correlated with a progressive increase in the number of neuronal cell classes, and reflected in behavior complexity.


La estructura morfológica e histológica de los cerebros de Bufo gargarizans y Cynops orientalis se observó mediante anatomía y microscopía óptica. Los resultados muestran que los cerebros de Bufo gargarizans y Cynops orientalis se dividen en 5 partes, que incluyen el telencéfalo, diencéfalo, mesencéfalo, cerebelo y mielencéfalo. El telencéfalo consiste en bulbo olfatorio y hemisferio cerebral. El bulbo olfatorio tiene dos pares de nervios olfatorios. Los lóbulos ópticos de Bufo gargarizans son ovalados y simétricos en ambos hemisferios cerebrales; Cynops orientalis tiene solo un lóbulo óptico esférico. El cerebelo está situado detrás del lóbulo óptico y está estrechamente conectado con el mielencéfalo. En este trabajo, se discuten las diferencias morfológicas e histológicas entre las dos especies. El tamaño del hemisferio cerebral aumenta gradualmente, lo que se correlaciona con un aumento progresivo de células neuronales en los núcleos, reflejándose en la complejidad del comportamiento.


Assuntos
Animais , Salamandridae/anatomia & histologia , Encéfalo/anatomia & histologia , Bufo bufo/anatomia & histologia , Anatomia Comparada , Telencéfalo/anatomia & histologia , Mesencéfalo/anatomia & histologia , Cerebelo/anatomia & histologia , Diencéfalo/anatomia & histologia , Mielencéfalo/anatomia & histologia
15.
Curr Biol ; 29(16): R794-R796, 2019 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-31430475

RESUMO

Despite the negative connotations of the term 'birdbrain', birds possess cognitive abilities on par with primates. A new study finds that neurons in the crow's brain display characteristics similar to those displayed by neurons in the primate's brain.


Assuntos
Corvos , Animais , Encéfalo , Memória de Curto Prazo , Neurônios , Primatas , Telencéfalo
16.
EMBO Rep ; 20(10): e47880, 2019 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-31469223

RESUMO

Microinjection into single cells in brain tissue is a powerful technique to study and manipulate neural stem cells. However, such microinjection requires expertise and is a low-throughput process. We developed the "Autoinjector", a robot that utilizes images from a microscope to guide a microinjection needle into tissue to deliver femtoliter volumes of liquids into single cells. The Autoinjector enables microinjection of hundreds of cells within a single organotypic slice, resulting in an overall yield that is an order of magnitude greater than manual microinjection. The Autoinjector successfully targets both apical progenitors (APs) and newborn neurons in the embryonic mouse and human fetal telencephalon. We used the Autoinjector to systematically study gap-junctional communication between neural progenitors in the embryonic mouse telencephalon and found that apical contact is a characteristic feature of the cells that are part of a gap junction-coupled cluster. The throughput and versatility of the Autoinjector will render microinjection an accessible high-performance single-cell manipulation technique and will provide a powerful new platform for performing single-cell analyses in tissue for bioengineering and biophysics applications.


Assuntos
Encéfalo/citologia , Microinjeções , Robótica , Análise de Célula Única , Animais , Automação , Comunicação Celular , Linhagem da Célula , Humanos , Processamento de Imagem Assistida por Computador , Camundongos Endogâmicos C57BL , Células-Tronco Neurais/citologia , Neurogênese , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Telencéfalo/citologia , Telencéfalo/embriologia
17.
Surg Radiol Anat ; 41(9): 1037-1044, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31250136

RESUMO

BACKGROUND AND PURPOSE: The subcallosal artery [SCA, a branch of the anterior communicating artery (ACoA)] is not well described in the literature. However, the memory disorders that can occur after surgical repair of ruptured ACoA aneurysms might be related to infarction of the SCA. The objective of the present study was to perform a thorough anatomical assessment of the SCA. METHODS: The study was carried out over a 6-month period in a University Hospital's anatomy laboratory, using brains extracted from human cadavers. The brains were injected with colored neoprene latex and dissected to study the SCA's origin, path, termination, diameter, length, and vascularized territories. RESULTS: 21 cadaveric specimens were studied. The mean ± standard deviation diameter and length of the SCA were 0.83 ± 0.57 mm and 38.14 ± 25.11 mm, respectively. The predominantly vascularized territories were the paraterminal gyrus (100%), the parolfactory gyrus (78.95%), the rostrum (84.21%) and genu (78.95%) of the corpus callosum, the lamina terminalis (78.95%), the anterior commissure (63.16%), the anterior cingulate gyrus (47.37%), and the fornix (26.32%). When the SCA supplied the fornix and the anterior cingulate gyrus, it was significantly longer and broader (p < 0.05). CONCLUSION: Anatomic knowledge of the SCA is crucial-especially for the treatment of ACoA aneurysms.


Assuntos
Artéria Cerebral Anterior/anatomia & histologia , Aneurisma Intracraniano/cirurgia , Microcirurgia/métodos , Telencéfalo/irrigação sanguínea , Cadáver , Dissecação/métodos , Humanos
18.
Brain Struct Funct ; 224(7): 2325-2341, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31203451

RESUMO

In mammals, the development of the olfactory bulb (OB) relies in part on the expression of transcription factors involved in the specifications/differentiation of glutamatergic cells. In a previous study from our group, a high molecular similarity was reported between mammals and cartilaginous fishes regarding the neurogenic mechanisms underlying the development of glutamatergic cells in the telencephalon. However, information about the transcriptional program operating in the development of the glutamatergic system (mainly represented by mitral cells) in the OB is lacking in the catshark Scyliorhinus canicula, a cartilaginous fish. Using immunohistochemistry and in situ hybridization techniques, we have found that, previously to the appearance of the olfactory primordium (OP), proliferating cells expressing Pax6 with molecular hallmarks of progenitor radial glia were located in the ventrolateral pallial ventricular zone. Later in development, when the OP is recognizable, a stream of Pax6-positive cells were observed between the ventricular zone and the OP, where transcription factors involved in mitral cell development in mammals (ScTbr2, ScNeuroD, Tbr1) are expressed. Later in development, these transcription factors became expressed in a layered-like structure where ScVglut1, a marker of mitral cells, is also present. Our data suggest that the transcriptional program related with the specification/differentiation of glutamatergic cells in the telencephalon has been conserved throughout the evolution of vertebrates. These results, in combination with previous studies concerning GABAergic neurogenesis in sharks, have evidenced that the OB of mammals and sharks shares similarities in the timing and molecular programs of development.


Assuntos
Diferenciação Celular/fisiologia , Células-Tronco Neurais/metabolismo , Neurogênese/fisiologia , Bulbo Olfatório/metabolismo , Animais , Movimento Celular/fisiologia , Proliferação de Células/fisiologia , Proteínas do Olho/metabolismo , Proteínas de Homeodomínio/metabolismo , Fatores de Transcrição Box Pareados/metabolismo , Tubarões/metabolismo , Telencéfalo/metabolismo
19.
eNeuro ; 6(2)2019.
Artigo em Inglês | MEDLINE | ID: mdl-31068363

RESUMO

In male songbirds, the motivation to sing is largely regulated by testosterone (T) action in the medial preoptic area, whereas T acts on song control nuclei to modulate aspects of song quality. Stereotaxic implantation of T in the medial preoptic nucleus (POM) of castrated male canaries activates a high rate of singing activity, albeit with a longer latency than after systemic T treatment. Systemic T also increases the occurrence of male-like song in female canaries. We hypothesized that this effect is also mediated by T action in the POM. Females were stereotaxically implanted with either T or with 17ß-estradiol (E2) targeted at the POM and their singing activity was recorded daily during 2 h for 28 d until brains were collected for histological analyses. Following identification of implant localizations, three groups of subjects were constituted that had either T or E2 implanted in the POM or had an implant that had missed the POM (Out). T and E2 in POM significantly increased the number of songs produced and the percentage of time spent singing as compared with the Out group. The songs produced were in general of a short duration and of poor quality. This effect was not associated with an increase in HVC volume as observed in males, but T in POM enhanced neurogenesis in HVC, as reflected by an increased density of doublecortin-immunoreactive (DCX-ir) multipolar neurons. These data indicate that, in female canaries, T acting in the POM plays a significant role in hormone-induced increases in the motivation to sing.


Assuntos
Estradiol/fisiologia , Motivação/fisiologia , Neurogênese/fisiologia , Área Pré-Óptica/metabolismo , Telencéfalo/metabolismo , Testosterona/fisiologia , Vocalização Animal/fisiologia , Animais , Canários , Estradiol/farmacologia , Feminino , Motivação/efeitos dos fármacos , Neurogênese/efeitos dos fármacos , Área Pré-Óptica/efeitos dos fármacos , Telencéfalo/efeitos dos fármacos , Testosterona/farmacologia , Vocalização Animal/efeitos dos fármacos
20.
Braz J Med Biol Res ; 52(5): e8026, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31038577

RESUMO

Carassius auratus is a teleost fish that has been largely used in behavioral studies. However, little is known about potential environmental influences on its performance of learning and memory tasks. Here, we investigated this question in C. auratus, and searched for potential correlation between exercise and visuospatial enrichment with the total number of telencephalic glia and neurons. To that end, males and females were housed for 183 days in either an enriched (EE) or impoverished environment (IE) aquarium. EE contained toys, natural plants, and a 12-hour/day water stream for voluntary exercise, whereas the IE had none of the above. A third plus-maze aquarium was used for spatial and object recognition tests. Different visual clues in 2 of its 4 arms were used to guide fish to reach the criteria to complete the task. The test consisted of 30 sessions and was concluded when each animal performed three consecutive correct choices or seven alternated, each ten trials. Learning rates revealed significant differences between EE and IE fish. The optical fractionator was used to estimate the total number of telencephalic cells that were stained with cresyl violet. On average, the total number of cells in the subjects from EE was higher than those from subjects maintained in IE (P=0.0202). We suggest that environmental enrichment significantly influenced goldfish spatial learning and memory abilities, and this may be associated with an increase in the total number of telencephalic cells.


Assuntos
Proliferação de Células/fisiologia , Peixes/fisiologia , Aprendizagem Espacial/fisiologia , Memória Espacial/fisiologia , Telencéfalo/metabolismo , Animais , Comportamento Animal/fisiologia , Contagem de Células , Feminino , Masculino , Condicionamento Físico Animal
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