Navegando por Palavras-chave "Cuprizone"
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- ItemSomente MetadadadosAnálise de parâmetros inflamatórios e comportamentais em decorrência da indução da desmielinização química com cuprizona em ratos lewis expostos ao enriquecimento ambiental(Universidade Federal de São Paulo (UNIFESP), 2014-07-30) Serra-Oliveira, Nathalia [UNIFESP]; Castro, Glaucia Monteiro de [UNIFESP]; http://lattes.cnpq.br/2727707909050870; http://lattes.cnpq.br/2634685799181212; Universidade Federal de São Paulo (UNIFESP)The myelin in the central nervous system (CNS) is vulnerable to damage due to metabolic, toxic or autoimmune attacks change. In this way, neurological damage such as demyelination causes motor, sensory, and behavioral changes. Multiple sclerosis is one of the most prevalent demyelinating disorders resulting from an aberrant immune response directed against oligodendrocytes. One of the biggest challenges is to find strategies that improve the remyelination process, although it occurs, is usually incomplete or failed. In this context, cuprizone has been used as animal model of demyelination, sharing some characteristics of multiple sclerosis. It is known that sensory, motor, cognitive and social stimulus modulate the CNS throughout life and the exposure to enriched environment (EE) provides new sensorimotor experiences, enhancing integration of CNS and promoting neuroplasticity. We hypothesize that the clinical signs of demyelination induced by cuprizone can be minimized by daily exposure to EE. In behavioral tests, it was found that the cuprizone group showed impairment in motor coordination in sensitivity and exploratory behavioral, similar to signs of anxiety. On the other hand, the EE minimized or reversed behavioral changes resulting from cuprizone. In demyelinated lesion, the density of oligodendrocytes is reduced, the astrocytic and microglial activation are increased in the corpus callosum compared with the control group, however the EE reduced the damage caused to oligodendrocytes by cuprizone. The TNF-? induces apoptosis of oligodendrocytes, accentuating demyelination. It was found that the concentrations of this cytokine significantly increased when compared to the cuprizone EE and control groups. Our results suggest that the EE can minimize the impact of white mater lesions enabling improved clinical signs and behavioral changes caused by demyelination exerting neuroprotective action.
- ItemAcesso aberto (Open Access)Avaliação do efeito do ambiente enriquecido sobre o processo de desmielinização e remielinização(Universidade Federal de São Paulo (UNIFESP), 2011-11-23) Oliveira, Nathalia Serra de [UNIFESP]; Castro, Glaucia Monteiro de [UNIFESP]; http://lattes.cnpq.br/2727707909050870; http://lattes.cnpq.br/2634685799181212; Universidade Federal de São Paulo (UNIFESP)A Esclerose Múltipla (EM) é uma doença neurológica crônica, inflamatória, desmielinizante do Sistema Nervoso Central (SNC). Para seu estudo diversos modelos vêm sendo utilizados, entre os quais desmielinização induzida com cuprizona, a qual desencadeia alterações comportamentais nos animais. Estudos recentes fornecem novos parâmetros sobre a ação do enriquecimento ambiental e sua relevância para o envelhecimento e doenças neurodegenerativas. O enriquecimento ambiental é uma condição de habitação para animais que permite maior estimulação sensorial, motora, social e cognitiva em relação às condiçõespadrão, proporcionando a reorganização funcional dos circuitos neuronais. O presente estudo tem por objetivo avaliar o processo de desmielinização e neurotoxicidade desencadeado pelo tratamento com a cuprizona frente à exposição ao ambiente enriquecido. Foram utilizados ratos da linhagem Lewis, machos com idade de sete semanas. Os animais controle receberam ração comercial moída e o grupo tratado recebeu ração moída com adição de cuprizona (0,6%) por 4 semanas. Os grupos que passaram por o período de recuperação receberam a ração comercial normal por mais uma semana, totalizando 5 semanas. Animais pertencentes aos grupos de ambiente enriquecido foram expostos a sessões diárias de uma hora durante o período experimental. Na primeira, terceira e última semana do tratamento, os animais foram submetidos a testes de comportamento e neurotoxicidade. Grupos tratados com cuprizona apresentam escores de neurotoxicidade significativamente mais elevados (p < 0,001) 15 dias após início do tratamento. Os resultados do teste Walking Track demonstraram impressão completa e uniforme das patas dos animais do grupo controle. Por outro lado, a impressão das patas dos animais tratados apresentou-se errátil e sem uniformidade de caminhada e na distância entre as pegadas. Animais expostos ao ambiente enriquecido e ao período de recuperação apresentam impressão uniforme, semelhante aos dos animais controle. No Campo aberto, notou-se redução significativa na quantidade de cruzamentos e na exploração vertical nos grupos tratados com cuprizona quando comparado ao grupo controle, por outro lado animais tratados expostos ao ambiente enriquecido apresentam índices semelhantes aos dos animais controle. No teste do labirinto em cruz, com o decorrer do tratamento, o grupo cuprizona aumentou significativamente sua permanência no braço fechado e diminuiu significativamente sua permanência no braço aberto. Animais tratados que frequentaram sessões de ambiente enriquecido apresentam índices semelhantes ao grupo controle e na analise do processo de desmielinização com Luxol Fast Blue apresentam densidade intermediaria entre os grupos controle após o período de recuperação. Estes dados sugerem que a exposição ao ambiente enriquecido pode atuar na recuperação dos animais com desmielinização induzida pela cuprizona, estimulando a regeneração.
- ItemSomente MetadadadosBehavioural changes observed in demyelination model shares similarities with white matter abnormalities in humans(Elsevier B.V., 2015-07-01) Oliveira, Nathalia Serra de [UNIFESP]; Boilesen, Sabine Nunes [UNIFESP]; Carvalho, Carolina Prado de França [UNIFESP]; Le Sueur-Maluf, Luciana [UNIFESP]; Zollner, Ricardo de Lima; Spadari, Regina Celia [UNIFESP]; Medalha, Carla Christina [UNIFESP]; Castro, Glaucia Monteiro de [UNIFESP]; Universidade Federal de São Paulo (UNIFESP); Universidade Estadual de Campinas (UNICAMP)Multiple sclerosis (MS) is a chronic, inflammatory, demyelinating disease of the central nervous system (CNS). Further to the symptoms resulting from demyelination, new studies point to the involvement of neuroinflammation and white matter abnormalities in psychiatric disorders and neurodegenerative diseases. Cuprizone, a model of MS, produces consistent demyelination and elicits behavioural, morphological and inflammatory changes in animals that share some similarities with those observed in humans. in this study, we used the cuprizone model in Lewis rats to evaluate clinical signs triggered by the demyelination process which could be comparable with the symptoms seen in white matter abnormalities in human beings. To induce the demyelination process, 0.6% cuprizone was added to the Lewis rats' diet for 4 weeks. We proceeded with behavioural, morphological and immunological analyses. Animals fed with cuprizone exhibited behavioural changes: higher scores in the neurotoxicity test, reduced exploratory and locomotion behaviour, and also an increase of permanency in the closed arm of the elevated plus maze test, were observed. in these analyses, the animals showed motor coordination impairment and anxiety-like behaviour. Demyelination also triggered changes in discrimination of objects identified by an increase in the time spent close to a familiar object. These behavioural alterations were associated with a significant increase in the levels of TNF-alpha and corticosterone, consistent with the activation of microglia and astrocytes. Taken together, the results of this work show the cuprizone/Lewis rat model demyelination as an attractive paradigm for studying the correlation between white matter abnormalities and behaviour. (C) 2015 Elsevier B.V. All rights reserved.
- ItemSomente MetadadadosEfeitos do laser de baixa intensidade na desmielinização induzida por cuprizona em camundongos(Universidade Federal de São Paulo (UNIFESP), 2016-03-24) Duarte, Katherine Chuere Nunes [UNIFESP]; Castro, Glaucia Monteiro de [UNIFESP]; http://lattes.cnpq.br/2727707909050870; http://lattes.cnpq.br/0526412538364715; Universidade Federal de São Paulo (UNIFESP)Multiple sclerosis is an autoimmune, inflammatory, and demyelinating disease of the central nervous system (CNS). The inflammation, mediated by immunological attacks against myelin, leads to demyelination and, subsequently, neuron loss. The lack of an efficient therapy as treatment of demyelination has motivated the investigation of new therapeutic approaches. Studies show that laser therapy is efficient in promoting neurogenesis and modulation of inflammation in rodents? CNS. The aim of this study was to evaluate the effects of low-level laser therapy (LLLT) on cuprizone induced demyelination. We used C57BL/6 mice, randomly distributed in Control Laser, Cuprizone, and Cuprizone Laser groups. Demyelination was induced by feeding the animals with a diet including 0.2% cuprizone for four weeks. The LLLT were applied in Control Laser and Cuprizone Laser mice for three consecutive days, in the third and fourth weeks of the experiment. Motor coordination was assessed by the rotarod test. Twenty-four hours after the final laser session, the animals were euthanized to collect blood and brains. Histological analyses were carried out by immunohistochemistry and Luxol Fast Blue staining (LFB). The results showed that laser-treated animals demonstrated better motor performance. In the nervous tissue, the LLLT treatment attenuated the demyelination indicated by LFB staining and immunolabeling. Laser therapy increased the number of oligodendrocytes precursor cells (OPCs), modulated microglial and astrocytes activation, and reduced toxicity induced by cuprizone. These results suggest that low-level laser therapy was effective in motor recovery, attenuation of demyelination, modulation of inflammation, proliferation of OPCs, and toxicity control