Data/hora: 05/06/2024 00:29:03

Provedor de dados: | Brazilian Journal of Medical and Biological Research
País: | Brazil
Título: | Modulation of ROS production in human leukocytes by ganglioside micelles
Autores: | Gavella,M.; Kveder,M.; Lipovac,V.
Data: | 2010-10-01
Ano: | 2010
Palavras-chave: | Ganglioside micelles; Reactive oxygen species; Human polymorphonuclear neutrophils.
Resumo: | Recent studies have reported that exogenous gangliosides, the sialic acid-containing glycosphingolipids, are able to modulate many cellular functions. We examined the effect of micelles of mono- and trisialoganglioside GM1 and GT1b on the production of reactive oxygen species by stimulated human polymorphonuclear neutrophils using different spectroscopic methods. The results indicated that exogenous gangliosides did not influence extracellular superoxide anion (O2.-) generation by polymorphonuclear neutrophils activated by receptor-dependent formyl-methionyl-leucyl-phenylalanine. However, when neutrophils were stimulated by receptor-bypassing phorbol 12-myristate 13-acetate (PMA), gangliosides above their critical micellar concentrations prolonged the lag time preceding the production in a concentration-dependent way, without affecting total extracellular O2.- generation detected by superoxide dismutase-inhibitable cytochrome c reduction. The effect of ganglioside GT1b (100 µM) on the increase in lag time was shown to be significant by means of both superoxide dismutase-inhibitable cytochrome c reduction assay and electron paramagnetic resonance spectroscopy (P &lt; 0.0001 and P &lt; 0.005, respectively). The observed phenomena can be attributed to the ability of ganglioside micelles attached to the cell surface to slow down PMA uptake, thus increasing the diffusion barrier and consequently delaying membrane events responsible for PMA-stimulated O2.- production.
Tipo: | Info:eu-repo/semantics/article
Idioma: | Inglês
Identificador: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2010001000004
Editor: | Associação Brasileira de Divulgação Científica
Relação: | 10.1590/S0100-879X2010007500092
Formato: | text/html
Fonte: | Brazilian Journal of Medical and Biological Research  v.43 n.10 2010
Fonte: | info:eu-repo/semantics/openAccess