Reactive oxygen species and p38 mitogen-activated protein kinase activate Bax to induce mitochondrial cytochrome c release and apoptosis in response to malonate
Identificadores
URI: http://hdl.handle.net/20.500.12020/1157ISSN: 15210111
DOI: https://doi.org/10.1124/mol.106.030718
Autor/es
Gómez-Lazaro, María; Galindo, María Francisca; Melero Fernández de Mera, Raquel María; Fernández Gómez, Francisco José; Cancannon, CG; [et al.]Fecha
2007Tipo de documento
articleMateria/s Unesco
32 Ciencias MédicasResumen
Malonate, an inhibitor of mitochondrial complex II, is a widely used toxin to study neurodegeneration in Huntington's disease and ischemic stroke. We have shown previously that malonate increased reactive oxygen species (ROS) production in human SH-SY5Y neuroblastoma cells, leading to oxidative stress, cytochrome c release, and apoptotic cell death. Expression of a green fluorescent protein-Bax fusion protein in SH-SY5Y neuroblastoma cells demonstrated a Bax redistribution from the cytosol to mitochondria after 12 to 24 h of malonate treatment that coincided with mitochondrial potential collapse and chromatin condensation. Inhibition of Bax translocation using furosemide, as well as Bax gene deletion, afforded significant protection against malonate-induced apoptosis. Further experiments revealed that malonate induced a prominent increase in the level of activated p38 mitogen-activated protein (MAP) kinase and that treatment with the p38 MAP kinase inhibitor SKF86002 potently blocked malonate-induced Bax translocation and apoptosis. Treatment with vitamin E diminished ROS production, reduced the activation status of p38 MAP kinase, inhibited Bax translocation, and protected against malonate-induced apoptosis. Our data suggest that malonate-induced ROS production and subsequent p38 MAP kinase activation mediates the activation of the pro-apoptotic Bax protein to induce mitochondrial membrane permeabilization and neuronal apoptosis.