Acute and severe hypobaric hypoxia-induced muscle oxidative stress in mice: the role of glutathione against oxidative damage

• Tipo: Artigo em Revista Científica Internacional
• Data: 2004

Autores

J. Magalhães (Autor) FADEUP; A. Ascensão (Autor) FADEUP; J. M. C. Soares (Autor) FADEUP; M. J. Neuparth (Autor) Outra; R. Ferreira (Autor) Outra; J. Oliveira (Autor) FADEUP; F. Amado (Autor) Outra; J. A. Duarte (Autor) FADEUP

Revista

Título: European Journal of Applied Physiology

Vol. 91

Páginas: 185-191

ISSN: 1439-6319

Editora: Springer Nature

Indexação

ISI Web of Knowledge - 24 Citações

Scopus - 24 Citações

Classificação Científica

FOS: Ciências médicas e da saúde > Medicina básica

Outras Informações

ID Authenticus: P-000-BC4

DOI: 10.1007/s00421-003-0972-6

Abstract (EN): This study intended to analyze: (1) the effects of acute and severe hypoxia exposure on skeletal muscle oxidative stress and oxidative damage markers; (2) the protective role of the antioxidant glutathione against oxidative damage; and (3) the expression of heat shock protein 70 kDa (HSP70) induced by this hypoxic insult. Forty mice were divided into four groups: control + placebo (C+P), hypoxia + placebo (H+P), control + L-buthionine-[S,R]-sulfoximine (BSO, a GSH-depleting compound) (C+BSO) and hypoxia + BSO (H+BSO). Hypoxia groups were continuously exposed for 24 h to a hypobaric hypoxic environment equivalent to an altitude of 7000 m and sacrificed immediately after. Control groups were maintained at sea level during the experimental protocol. Analyzed biochemical parameters were: reduced (GSH) and oxidized (GSSG) glutathione, thiobarbituric acid reactive substances (TBARS), sulfhydryl protein groups (SH), N-acetyl-beta-D-glucosaminidase (NAG) and HSP70 protein. Hypoxia (H+P) per se, compared to C+P, induced a significant increase in %GSSG (5.68 vs. 1.14%), TBARS (436.7 vs. 227.9 nM), NAG (4.49 vs. 3.35 U/mg) and HSP70 (178.7 vs. 100%). Compared with H+P, H+BSO showed a significant decrease in total glutathione (19.30 vs. 6.13 nmol/mg) and an additional increase in %GSSG (5.68 vs. 11.33%) and in HSP70 expression (178.7 vs. 202.2%). However, no further oxidative damage was observed in H+BSO. These data suggest that acute hypoxia per se might enhance oxidative stress; however, the glutathione system seems to have a modest role in skeletal muscle protection against hypoxia-induced oxidative stress. Moreover, hypoxia and BSO treatment is a sufficient stimulus to promote HSP70 overexpression.

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 7