A hipermetioninemia reduz os níveis de fosfolipídios, colesterol e gangliosídios em córtex cerebral de ratos

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Aplicação de anticorpos biespecíficos como imunoreagentes : estudo da cinética de reação da enzima fosfatase alcalina e sua modulação com anticorpos anti-enzima

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Conteúdo lipídico em córtex cerebral, hipotálamo, hipocampo e cerebelo de atos submetidos a um modelo experimental de hiperprolinemia II

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Conteúdo lipídico em córtex cerebral, hipotálamo, hipocampo e cerebelo de atos submetidos a um modelo experimental de hiperprolinemia II

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Avaliação do conteúdo e do perfil de gangliosídios em diferentes estruturas cerebrais em um modelo murino da mucopolissacadidose tipo I (MPS I)

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Avaliação do conteúdo e do perfil de gangliosídios em diferentes estruturas cerebrais em um modelo murino da mucopolissacadidose tipo I (MPS I)

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A hipermetioninemia reduz os níveis de fosfolipídios, colesterol e gangliosídios em córtex cerebral de ratos

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Reduction of gangliosides, phospholipids and cholesterol content in cerebral cortex of rats caused by chronic hypermethioninemia

Neurological dysfunction is observed in patients with severe hypermethioninemia, whose physiopathology is still poorly understood. In the current study we investigated the effect of chronic administration of methionine on the content and species of gangliosides and phospholipids, as well as on the concentration of cholesterol in rat cerebral cortex. Wistar rats received subcutaneous injections of methionine (1.34–2.68 μmol/g of body weight), twice a day, from the 6th to the 28th day of age and controls received saline. Animals were killed 12 h after the last injection. Results showed that methionine administration significantly decreased the total content of lipids in cerebral cortex of rats. We also observed that this amino acid significantly reduced the absolute quantity of the major brain gangliosides (GM1, GD1a, GD1b and GT1b) and phospholipids (sphingomyelin, phosphatidylcholine and phosphatidylethanolamine). We also showed that Na+,K+-ATPase activity and TBARS were changed in cerebral cortex of rats subjected to hypermethioninemia. If confirmed in human beings, these data could suggest that the alteration in lipid composition, Na+,K+-ATPase activity and TBARS caused by methionine might contribute to the neurophysiopathology observed in hypermethioninemic patients

Effects of chronic proline administration on lipid contents of rat brain

In the present work we investigated the effects of chronic proline administration on ganglioside, cholesterol and phospholipid total contents, as well as on ganglioside profile in cerebral cortex, hippocampus, hypothalamus and cerebellum of rats. We also evaluated the ganglioside content and profile in detergent-soluble and resistant microdomains isolated from synaptic membranes obtained from cerebral cortex. Proline solution (hyperprolinemic) or saline (control) were subcutaneously administered to rats from 6th to 28th post-natal day, according to body weight. Twelve hours after the last injection, the animals were sacrificed by decapitation without anaesthesia. Brain structures were homogenized with chloroform:methanol for lipid extraction. Synaptic membranes were obtained by differential centrifugation and detergent-soluble and resistant microdomains were isolated by cold Triton X-100 treatment. Results showed that rats subjected to chronic proline treatment presented a significant increase of ganglioside content in cortex and hippocampus, while this membrane lipid content was not altered in hypothalamus and cerebellum. Besides, phospholipid and cholesterol contents were not modified in all structures studied. On the other hand, ganglioside content decreased in detergent-soluble and resistant microdomains isolated from synaptic membrane obtained from hyperprolinemic cortex. Although ganglioside profiles were apparently not modified, the individual absolute quantities were altered in cortex and hippocampus total lipid extract and membrane microdomains. Our findings suggest that chronic proline treatment affects in a distinct manner different cerebral regions concerning the lipid composition of the cell membranes, reflecting on its distribution in the cortex membrane microdomains. Among these phenomena consequences, distinct modulations in synaptic transmission may be suggested which might contribute to the impairment in cognition and/or other neurological dysfunctions found in hyperprolinemia type II patients