Glucose ingestion during exercise blunts exercise-induced gene expression of skeletal muscle fat oxidative genes.
Data(s) |
19/07/2005
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Resumo |
Ingestion of carbohydrate during exercise may blunt the stimulation of fat oxidative pathways by raising plasma insulin and glucose concentrations and lowering plasma free fatty acid (FFA) levels, thereby causing a marked shift in substrate oxidation. We investigated the effects of a single 2-h bout of moderate-intensity exercise on the expression of key genes involved in fat and carbohydrate metabolism with or without glucose ingestion in seven healthy untrained men (22.7 ± 0.6 yr; body mass index: 23.8 ± 1.0 kg/m<sup>2</sup>; maximal O2 consumption: 3.85 ± 0.21 l/min). Plasma FFA concentration increased during exercise (<i>P</i> < 0.01) in the fasted state but remained unchanged after glucose ingestion, whereas fat oxidation (indirect calorimetry) was higher in the fasted state vs. glucose feeding (<i>P</i> < 0.05). Except for a significant decrease in the expression of pyruvate dehydrogenase kinase-4 (<i>P</i> < 0.05), glucose ingestion during exercise produced minimal effects on the expression of genes involved in carbohydrate utilization. However, glucose ingestion resulted in a decrease in the expression of genes involved in fatty acid transport and oxidation (CD36, carnitine palmitoyltransferase-1, uncoupling protein 3, and 5'-AMP-activated protein kinase-α2; <i>P</i> < 0.05). In conclusion, glucose ingestion during exercise decreases the expression of genes involved in lipid metabolism rather than increasing genes involved in carbohydrate metabolism.<br /> |
Identificador | |
Idioma(s) |
eng |
Publicador |
American Physiological Society |
Relação |
http://dro.deakin.edu.au/eserv/DU:30004097/n20062094.pdf http://dx.doi.org/10.1152/ajpendo.00193.2005 |
Direitos |
2005, American Physiological Society |
Palavras-Chave | #skeletal muscle gene expression #exercise-diet interaction |
Tipo |
Journal Article |