HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) All Versions of this Article: 296/4/E787    most recent 90556.2008v1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Frøsig, C. Articles by Kiens, B. Search for Related Content PubMed PubMed Citation Articles by Frøsig, C. Articles by Kiens, B.

Reduced malonyl-CoA content in recovery from exercise correlates with improved insulin-stimulated glucose uptake in human skeletal muscle

Copenhagen Muscle Research Centre, Molecular Physiology Group, Section of Human Physiology, Department of Exercise and Sport Sciences, University of Copenhagen, Copenhagen, Denmark

Submitted 1 July 2008 ; accepted in final form 27 January 2009

This study evaluated whether improved insulin-stimulated glucose uptake in recovery from acute exercise coincides with reduced malonyl-CoA (MCoA) content in human muscle. Furthermore, we investigated whether a high-fat diet [65 energy-% (Fat)] would alter the content of MCoA and insulin action compared with a high-carbohydrate diet [65 energy-% (CHO)]. After 4 days of isocaloric diet on two occasions (Fat/CHO), 12 male subjects performed 1 h of one-legged knee extensor exercise (80% peak workload). Four hours after exercise, insulin-stimulated glucose uptake was determined in both legs during a euglycemic-hyperinsulinemic clamp. Muscle biopsies were obtained in both legs before and after the clamp. Four hours after exercise, insulin-stimulated glucose uptake was improved (70%, P < 0.001) independent of diet composition and despite normal insulin-stimulated regulation of insulin receptor substrate-1-associated phosphatidylinositol 3-kinase, Akt, GSK-3, and glycogen synthase. Interestingly, exercise resulted in a sustained reduction (20%, P < 0.05) in MCoA content 4 h after exercise that correlated (r = 0.65, P < 0.001) with improved insulin-stimulated glucose uptake. Four days of Fat diet resulted in an increased content of intramyocellular triacylglycerol (P < 0.01) but did not influence muscle MCoA content or whole body insulin-stimulated glucose uptake. However, at the muscular level proximal insulin signaling and insulin-stimulated glucose uptake appeared to be compromised, although to a minor extent, by the Fat diet. Collectively, this study indicates that reduced muscle MCoA content in recovery from exercise may be part of the adaptive response leading to improved insulin action on glucose uptake after exercise in human muscle.

AMP-activated protein kinase; acetyl coenzyme A carboxylase; intramuscular triacylglycerol; Akt; diet