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

This Article Full Text Free Full Text (PDF) Free All Versions of this Article: 102/4/1624    most recent 00821.2006v1 Submit a response Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Web of Science (2) Citing Articles via Google Scholar Google Scholar Articles by Wadley, G. D. Articles by Cameron-Smith, D. Search for Related Content PubMed PubMed Citation Articles by Wadley, G. D. Articles by Cameron-Smith, D.

Increased insulin-stimulated Akt pSer⁴⁷³ and cytosolic SHP2 protein abundance in human skeletal muscle following acute exercise and short-term training

¹School of Exercise and Nutrition Sciences, Deakin University, Burwood, Victoria; ²Department of Physiology, The University of Melbourne, Parkville, Victoria; ³Commonwealth Scientific and Industrial Research Organisation Molecular and Health Technologies, Parkville, Victoria; and ⁴Metabolic Research Unit, Deakin University, Geelong, Victoria, Australia

Submitted 26 July 2006 ; accepted in final form 16 December 2006

The purpose of the present study was to determine in human skeletal muscle whether a single exercise bout and 7 days of consecutive endurance (cycling) training 1) increased insulin-stimulated Akt pSer⁴⁷³ and 2) altered the abundance of the protein tyrosine phosphatases (PTPases), PTP1B and SHP2. In healthy, untrained men (n = 8; 24 ± 1 yr), glucose infusion rate during a hyperinsulinemic euglycemic clamp, when compared with untrained values, was not improved 24 h following a single 60-min bout of endurance cycling but was significantly increased (30%; P < 0.05) 24 h following completion of 7 days of exercise training. Insulin-stimulated Akt pSer⁴⁷³ was 50% higher (P < 0.05) 24 h following the acute bout of exercise, with this effect remaining after 7 days of training (P < 0.05). Insulin-stimulated insulin receptor and insulin receptor substrate-1 tyrosine phosphorylation were not altered 24 h after acute exercise and short-term training. Insulin did not acutely regulate the localization of the PTPases, PTP1B or SHP2, although cytosolic protein abundance of SHP2 was increased (P < 0.05; main effect) 24 h following acute exercise and short-term training. In conclusion, insulin-sensitive Akt pSer⁴⁷³ and cytosolic SHP2 protein abundance are higher after acute exercise and short-term training, and this effect appears largely due to the residual effects of the last bout of prior exercise. The significance of exercise-induced alterations in cytosolic SHP2 and insulin-stimulated Akt pSer⁴⁷³ on the improvement in insulin sensitivity requires further elucidation.

contraction; insulin-signaling; protein phosphatases

This article has been cited by other articles:

				T. Nedachi, H. Fujita, and M. Kanzaki Contractile C2C12 myotube model for studying exercise-inducible responses in skeletal muscle Am J Physiol Endocrinol Metab, November 1, 2008; 295(5): E1191 - E1204. [Abstract] [Full Text] [PDF]

				S. Fujita, B. B. Rasmussen, J. G. Cadenas, M. J. Drummond, E. L. Glynn, F. R. Sattler, and E. Volpi Aerobic Exercise Overcomes the Age-Related Insulin Resistance of Muscle Protein Metabolism by Improving Endothelial Function and Akt/Mammalian Target of Rapamycin Signaling Diabetes, June 1, 2007; 56(6): 1615 - 1622. [Abstract] [Full Text] [PDF]