Myotube depolarization generates reactive oxygen species through NAD(P)H oxidase; ROS-elicited Ca2+ stimulates ERK, CREB, early genes

Espinosa, A.; Leiva A.; Pena M.; Muller, M.; Debandi A.; Hidalgo C.; Carrasco MA; Jaimovich E.

Abstract

Controlled generation of reactive oxygen species (ROS) may contribute to physiological intracellular signaling events. We determined ROS generation in primary cultures of rat skeletal muscle after field stimulation (4001-ms pulses at a frequency of 45 Hz) or after depolarization with 65 mM K+ for 1 min. Both protocols induced a long lasting increase in dichlorofluorescein fluorescence used as ROS indicator. Addition of diphenyleneiodonium (DPI), an inhibitor of NAD(P)H oxidase, PEG-catalase, a ROS scavenger, or nifedipine, an inhibitor of the skeletal muscle voltage sensor, significantly reduced this increase. Myotubes contained both the p47phox and gp91phox phagocytic NAD(P)H oxidase subunits, as revealed by immunodetection. To study the effects of ROS, myotubes were exposed to hydrogen peroxide (H 2O2) at concentrations (100-200 μM) that did not alter cell viability; H2O2 induced a transient intracellular Ca2+ rise, measured as fluo-3 fluorescence. Minutes after Ca 2+ signal initiation, an increase in ERK1/2 and CREB phosphorylation and of mRNA for the early genes c-fos and c-jun was detected. Inhibition of ryanodine receptor (RyR) decreased all effects induced by H2O 2 and NAD(P)H oxidase inhibitors DPI and apocynin decreased ryanodine-sensitive calcium signals. Activity-dependent ROS generation is likely to be involved in regulation of calcium-controlled intracellular signaling pathways in muscle cells. © 2006 Wiley-Liss, Inc.

Más información

Título según WOS: Myotube depolarization generates reactive oxygen species through NAD(P)H oxidase; ROS-elicited Ca2+ stimulates ERK, CREB, early genes
Título según SCOPUS: Myotube depolarization generates reactive oxygen species through NAD(P)H oxidase; ROS-elicited Ca2+ stimulates ERK, CREB, early genes
Título de la Revista: JOURNAL OF CELLULAR PHYSIOLOGY
Volumen: 209
Número: 2
Editorial: WILEY-BLACKWELL
Fecha de publicación: 2006
Página de inicio: 379
Página final: 388
Idioma: English
URL: http://doi.wiley.com/10.1002/jcp.20745
DOI:

10.1002/jcp.20745

Notas: ISI, SCOPUS