Effect of dimethylsufoxide on sphingomyelinase activity and cholesterol metabolism in Niemann-Pick type C fibroblasts

Niemann-Pick type C (NPC) fibroblasts present a large concentration of cholesterol in their cytoplasm due to a still unidentified deficiency in cholesterol metabolism. The influence of dimethylsulfoxide (DMSO) on the amount of intracellular cholesterol was measured in 8 cultures of normal fibroblast...

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Detalles Bibliográficos
Autores: Scalco, Fernanda Bertao, Giugliani, Roberto, Tobo, Patricia R., Coelho, Janice Carneiro
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:1999
País:Brasil
Institución:Universidade Federal do Rio Grande do Sul (UFRGS)
Repositorio:Repositório Institucional da UFRGS
Idioma:portugués
OAI Identifier:oai:www.lume.ufrgs.br:10183/21127
Acceso en línea:http://hdl.handle.net/10183/21127
Access Level:acceso abierto
Palabra clave:Dimetil sulfóxido
Colesterol
Esfingomielina fosfodiesterase
Doenças de Niemann-Pick
Cholesterol metabolism
Sphingomyelinase
Niemann-Pick disease
Lysosomal storage disorders
Descripción
Sumario:Niemann-Pick type C (NPC) fibroblasts present a large concentration of cholesterol in their cytoplasm due to a still unidentified deficiency in cholesterol metabolism. The influence of dimethylsulfoxide (DMSO) on the amount of intracellular cholesterol was measured in 8 cultures of normal fibroblasts and in 7 fibroblast cultures from NPC patients. DMSO was added to the fibroblast cultures at three different concentrations (1, 2 and 4%, v/v) and the cultures were incubated for 24 h. Sphingomyelinase activity was significantly increased in both groups of cells only when incubated with 2% DMSO (59.4 ± 9.1 and 77.0 ± 9.1 nmol h-1 mg protein-1, controls without and with 2% DMSO, respectively; 47.7 ± 5.2 and 55.8 ± 4.1 nmol h-1 mg protein-1, NPC without and with 2% DMSO, respectively). However, none of the DMSO concentrations used altered the amount of cholesterol in the cytoplasm of NPC cells (0.704 ± 0.049, 0.659 ± 0.041, 0.688 ± 0.063 and 0.733 ± 0.088 mg/mg protein, without DMSO, 1% DMSO, 2% DMSO and 4% DMSO, respectively). This finding suggests that sphingomyelinase deficiency is a secondary defect in NPC and shows that DMSO failed to remove the stored cholesterol. These data do not support the use of DMSO in the treatment of NPC patients.