Effect of short-term training on GLUT-4 mRNA and protein expression in human skeletal muscle
Data(s) |
01/09/2004
|
---|---|
Resumo |
Six untrained, male subjects (23 ± 1 years old, 84 ± 5 kg, V<sub>O2peak</sub>= 3.7 ± 0.8 l min<sup>–1</sup>) exercised for 60 min at 75 ± 1%V<sub>O2peak</sub> on 7 consecutive days. Muscle samples were obtained before the start of cycle exercise training and 24 h after the first and seventh exercise sessions and analysed for citrate synthase activity, glycogen and glucose transporter 4 (GLUT-4) mRNA and protein expression. Exercise training increased (<i>P</i> < 0.05) citrate synthase by ~20% and muscle glycogen concentration by ~40%. GLUT-4 mRNA levels 24 h after the first and seventh exercise sessions were similar to those measured before the start of exercise training. In contrast, GLUT-4 protein expression was increased after 7 days of exercise training (12.4 ± 1.5 <i>versus</i> 3.4 ± 1.0 arbitray units (a.u.), <i>P</i> < 0.05) and although it tended to be higher 24 h after the first exercise session (6.0 ± 3.0 <i>versus</i> 3.4 ± 1.0 a.u.), this was not significantly different (<i>P</i>= 0.09). These results support the suggestion that the adaptive increase in skeletal muscle GLUT-4 protein expression with short-term exercise training arises from the repeated, transient increases in GLUT-gene transcription following each exercise bout leading to a gradual accumulation of GLUT-4 protein, despite GLUT-4 mRNA returning to basal levels between exercise stimuli.<br /> |
Identificador | |
Idioma(s) |
eng |
Publicador |
Cambridge University Press for the Physiological Society |
Relação |
http://dro.deakin.edu.au/eserv/DU:30002463/n20040328.pdf http://ep.physoc.org/cgi/content/abstract/89/5/559 |
Direitos |
2004, The Physiological Society |
Tipo |
Journal Article |