Navegando por Palavras-chave "Medial ganglionic eminence"
Agora exibindo 1 - 5 de 5
Resultados por página
Opções de Ordenação
- ItemAcesso aberto (Open Access)Avaliação do transplante de células-tronco precursoras de neurônios inibitórios na amígdala basolateral em camundongos tratados com cocaína na ansiedade e na preferência condicionada por lugar e suas correlações neurobiológicas(Universidade Federal de São Paulo (UNIFESP), 2017-06-29) Yokoyama, Thais Suemi [UNIFESP]; Longo, Beatriz Monteiro [UNIFESP]; Marinho, Eduardo Ary Villela [UNIFESP]; http://lattes.cnpq.br/0245964878412260; http://lattes.cnpq.br/0245964878412260; http://lattes.cnpq.br/4851041162128915; Universidade Federal de São Paulo (UNIFESP)Drug addiction is one of the main problems modern society, as it can affect several areas of society, economy and public health. Studies have shown that in addition to the pharmacological effects of drugs of abuse, the environmental context where the individual makes use of it is extremely important for the development of dependence on the substance with potential for abuse. Moreover, they showed the important involvement of the basolateral amygdala by promoting desire for the use of the drug only by exposure to environments previously associated with such use. In order to better understand this pathology, we used stem cell transplantation, an inhibitory interneuron from the medial ganglionic eminence (EGM), to modulate pathways related to chemical dependence and to analyze possible behavioral changes. Thus, our objective was to evaluate the effects of stem cell transplantation of inhibitory interneuron on anxiety behaviors, preference conditioned by cocaine-induced site and characterize possible neuroanatomic structures involved in the conditioned response. For this, we used GFP + mice to obtain EGM stem cells and the hosts were Swiss mice at 2 months of age. After 30 days of cell transplantation, the animals were exposed to the high cross labyrinth for anxiety analysis, the next day the animals were conditioned to cocaine and submitted to the postconditioning test to evaluate the preference conditioned by place. Our results showed that inhibitory precursor cell transplantation was not able to alter anxiety behavior, but it potentiated cocaine- induced preference. In relation to the expression of c-fos, we evaluated the basolateral amygdala, medial prefrontal cortex, tegmental ventral area, nucleus accumbens (core and shell) and dorsal striatum. The expression of c-fos in the structures evaluated was not altered by the presence of EGM cells, only a pharmacological alteration of cocaine. Taken together, our results suggest that neural precursor transplantation from EGM is not capable of altering anxiety behavior, but has influenced cocaine-induced site-based preference
- ItemAcesso aberto (Open Access)Caracterização in vitro de precursores neuronais da eminência gangliônica medial e avaliação in vivo do seu potencial anticonvulsivo após transplante em animais epilépticos(Universidade Federal de São Paulo (UNIFESP), 2016-05-13) Romariz, Simone Amaro Alves [UNIFESP]; Longo, Beatriz Monteiro [UNIFESP]; http://lattes.cnpq.br/0245964878412260; http://lattes.cnpq.br/9325741054357205; Universidade Federal de São Paulo (UNIFESP)Epilepsia, crises epilépticas espontâneas e recorrentes se desenvolvem a partir de disparos neuronais contínuos e de alta frequência que podem ser gerados por uma disfunção sináptica inibitória. Portanto, as consequências da perda ou disfunção de interneurônios GABAérgicos no desenvolvimento do quadro epiléptico são importantes. Os interneurônios inibitórios se originam na região do telencéfalo conhecida como eminência gangliônica medial (EGM). Células progenitoras da EGM têm a capacidade de migrar e se diferenciar em interneurônios inibitórios GABAérgicos, modificando o tônus inibitório quando transplantadas no cérebro do hospedeiro. Assim, o transplante de células progenitoras derivadas da EGM pode modificar a circuitaria neuronal em disfunções neurológicas onde há alteração da função inibitória, como na epilepsia. No entanto, o transplante de células da EGM requer uma grande quantidade de células fetais, esbarrando em questões éticas. A expansão in vitro desses progenitores em neuroesferas pode ser uma alternativa para a aplicação terapêutica das células da EGM em maior escala. Nosso objetivo foi comparar diferentes condições de cultivo de neuroesferas derivadas da EGM quanto ao padrão de diferenciação neuronal e expressão de genes presentes na EGM in vitro e, avaliar in vivo após transplante em animais adultos no período epileptogênico, o potencial anticonvulsivo e de diferenciação em interneurônios inibitórios de células oriundas da EGM cultivadas ou não como neuroesferas. Os resultados in vitro mostraram que a remoção dos fatores de crescimento EGF e FGF2, bem como a adição de ácido retinóico ao meio de cultivo de neuroesferas oriundas da EGM aumentam a proporção de neurônios e a expressão de genes relacionados à especificação celular de interneurônios inibitórios nas neuroesferas, comparado à condição padrão de cultura. Os resultados in vivo indicam que as células derivadas da EGM que não foram cultivadas como neuroesferas originam mais interneurônios inibitórios e apresentam um efeito anticonvulsivo mais eficaz quando comparadas com células da EGM cultivadas como neuroesferas, independente das modificações realizadas no meio de cultivo. Dentre as células da EGM cultivadas como neuroesferas, as que foram cultivadas na presença de fatores de crescimento reduziram a frequência de crises do tipo IV e se diferenciaram, preferencialmente, em astrócitos. Concluímos que os precursores neuronais oriundos da região da EGM apresentam um potencial anticonvulsivo e que a técnica de expansão dessas células em neuroesferas, mesmo com as modificações no meio de cultivo, não favoreceu o aumento de interneurônios inibitórios após transplante em animais epilépticos. Apesar disso, as células cultivadas como neuroesferas na condição padrão se diferenciaram em astrócitos após o transplante, um tipo celular que pode ser importante no controle das crises espontâneas e recorrentes devido a possiveis mecanismos de redução de crises que devem ser melhor investigados.
- ItemAcesso aberto (Open Access)Long-lasting anxiolytic effect of neural precursor cells freshly prepared but not neurosphere-derived cell transplantation in newborn rats(Biomed Central Ltd, 2014-08-02) Romariz, Simone Amaro Alves [UNIFESP]; Paiva, Daisylea de Souza [UNIFESP]; Valente, Maria Fernanda [UNIFESP]; Barnabe, Gabriela Filoso [UNIFESP]; Frussa-Filho, Roberto [UNIFESP]; Silva, Regina Cláudia Barbosa da [UNIFESP]; Calcagnotto, Maria Elisa; Longo, Beatriz Monteiro [UNIFESP]; Universidade Federal de São Paulo (UNIFESP); Univ Fed Rio Grande do SulBackground: the GABAergic system plays an important role in modulating levels of anxiety. When transplanted into the brain, precursor cells from the medial ganglionic eminence (MGE) have the ability to differentiate into GABAergic interneurons and modify the inhibitory tone in the host brain. Currently, two methods have been reported for obtaining MGE precursor cells for transplantation: fresh and neurosphere dissociated cells. Here, we investigated the effects generated by transplantation of the two types of cell preparations on anxiety behavior in rats.Results: We transplanted freshly dissociated or neurosphere dissociated cells into the neonate brain of male rats on postnatal (PN) day 2-3. At early adulthood (PN 62-63), transplanted animals were tested in the Elevated Plus Maze (EPM). To verify the differentiation and migration pattern of the transplanted cells in vitro and in vivo, we performed immunohistochemistry for GFP and several interneuron-specific markers: neuropeptide Y (NPY), parvalbumin (PV) and calretinin (CR). Cells from both types of preparations expressed these interneuronal markers. However, an anxiolytic effect on behavior in the EPM was observed in animals that received the MGE-derived freshly dissociated cells but not in those that received the neurosphere dissociated cells.Conclusion: Our results suggest a long-lasting anxiolytic effect of transplanted freshly dissociated cells that reinforces the inhibitory function of the GABAergic neuronal circuitry in the hippocampus related to anxiety-like behavior in rats.
- ItemSomente MetadadadosMedial Ganglionic Eminence Cells Freshly Obtained or Expanded as Neurospheres Show Distinct Cellular and Molecular Properties in Reducing Epileptic Seizures(Wiley-Blackwell, 2017) Romariz, Simone A. A. [UNIFESP]; Paiva, Daisylea S. [UNIFESP]; Galindo, Layla T. [UNIFESP]; Barnabe, Gabriela F.; Guedes, Vivian A.; Borlongan, Cesario V.; Longo, Beatriz M. [UNIFESP]AimsMedial ganglionic eminence (MGE) progenitors give rise to inhibitory interneurons and may serve as an alternative cell source for large-scale cell transplantation for epilepsy after in vitro expansion. We investigated whether modifications in the culture medium of MGE neurospheres affect neuronal differentiation and expression of MGE-specific genes. In vivo, we compared anticonvulsant effects and cell differentiation pattern among neurospheres grown in different culture media and compared them with freshly harvested MGE cells. MethodsWe used four variations of cell culture: standard, containing growth factors (EGF/FGF-2) (GF)
- ItemSomente MetadadadosTransplantation of inhibitory precursor cells from medial ganglionic eminence produces distinct responses in two different models of acute seizure induction(Academic Press Inc Elsevier Science, 2017) Paiva, Daisylea de Souza [UNIFESP]; Alves Romariz, Simone Amaro [UNIFESP]; Valente, Maria Fernanda [UNIFESP]; Moraes, Luiz Bruno [UNIFESP]; Covolan, Luciene [UNIFESP]; Calcagnotto, Maria Elisa; Longo, Beatriz Monteiro [UNIFESP]Medial ganglionic eminence (MGE) is one of the sources of inhibitory interneurons during development. Following transplantation in postnatal developing brain, MGE cells can increase local inhibition suggesting a possible protection to GABAergic dysfunction in brain disorders, such as epilepsy. Since it has been shown that MGE-derived cells harvested as neurospheres are able to suppress seizures, it might be important to investigate whether these protective effects would change in different seizure models. Here, we used pentylenetetrazole(PTZ) and maximal electroshock (MES)-induced seizure models to test whether the transplantation of MGE cells would increase the threshold to trigger acute seizures. When transplanted into the neocortex (layers 3-4) of neonatal mice (postnatal days 3-4), MGE cells were able to survive and were mainly found in piriform cortex, fimbria, and ventricular wall regions. Additionally, the number of GFP + cells found in the brains of mice induced with PTZ and MES differed significantly and suggests proliferation and larger survival rate of MGE-transplanted cells after PTZ, but not MES-induced seizures. Following transplantation, there was a reduction in the number of animals presenting mild and severe seizures induced by PTZ. Furthermore, MGE-cell transplantation was able to increase threshold to seizures induced by PTZ, but was not able to prevent seizure spread induced by MES. (C) 2017 Elsevier Inc. All rights reserved.