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: 290/4/E731    most recent 00415.2005v1 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 HighWire Citing Articles via ISI Web of Science (15) Citing Articles via Google Scholar Google Scholar Articles by Cuthbertson, D. J. Articles by Rennie, M. Search for Related Content PubMed PubMed Citation Articles by Cuthbertson, D. J. Articles by Rennie, M.

Anabolic signaling and protein synthesis in human skeletal muscle after dynamic shortening or lengthening exercise

¹Department of Medicine, Ninewells Hospital and Medical School ²Division of Molecular Physiology, School of Life Sciences, University of Dundee, Dundee, Scotland ³School of Biomedical Sciences, Graduate Entry Medical School, University of Nottingham, Derby City Hospital, Derby, United Kingdom ⁴School of Kinesiology, University of Illinois, Chicago Illinois ⁵Department of Physiology College of Medicine, University of Kentucky, Lexington, Kentucky.

Submitted 1 September 2005 ; accepted in final form 26 October 2005

We hypothesized a differential activation of the anabolic signaling proteins protein kinase B (PKB) and p70 S6 kinase (p70^S6K) and subsequent differential stimulation of human muscle protein synthesis (MPS) after dynamic shortening or lengthening exercise. Eight healthy men [25 ± 5 yr, BMI 26 ± 3 kg/m^–2 (means ± SD)] were studied before and after 12 min of repeated stepping up to knee height, and down again, while carrying 25% of their body weight, i.e., shortening exercise with the "up" leg and lengthening exercise with contralateral "down" leg. Quadriceps biopsies were taken before and 3, 6, and 24 h after exercise. After exercise, over 2 h before the biopsies, the subjects ingested 500 ml of water containing 45 g of essential amino acids and 135 g of sucrose. Rates of muscle protein synthesis were determined via incorporation over time of [1-¹³C]leucine (6 h after exercise) or [1-¹³C]valine (21–24 h after exercise) and phosphorylation of signaling proteins by Western analysis. PKB and p70^S6K phosphorylation increased 3-fold after 3 h and remained elevated at 6 and 24 h. After exercise, rates of myofibrillar and sarcoplasmic protein synthesis were unchanged over the period including exercise and 3 h of recovery but had increased significantly at 6 (3.0- and 2.4-fold, respectively) and 24 h (3.2- and 2.0-fold, respectively), independently of the mode of exercise. Short-term dynamic exercise in either shortening or lengthening mode increases MPS at least as much as resistance exercise and is associated with long-term activation of PKB and p70^S6K.

exercise-induced anabolism; myofibrillar; sarcoplasmic; collagen synthesis

This article has been cited by other articles:

				L. Deldicque, P. Atherton, R. Patel, D. Theisen, H. Nielens, M. J. Rennie, and M. Francaux Effects of resistance exercise with and without creatine supplementation on gene expression and cell signaling in human skeletal muscle J Appl Physiol, February 1, 2008; 104(2): 371 - 378. [Abstract] [Full Text] [PDF]

				H. C. Dreyer, M. J. Drummond, B. Pennings, S. Fujita, E. L. Glynn, D. L. Chinkes, S. Dhanani, E. Volpi, and B. B. Rasmussen Leucine-enriched essential amino acid and carbohydrate ingestion following resistance exercise enhances mTOR signaling and protein synthesis in human muscle Am J Physiol Endocrinol Metab, February 1, 2008; 294(2): E392 - E400. [Abstract] [Full Text] [PDF]

				H. Mascher, J. Tannerstedt, T. Brink-Elfegoun, B. Ekblom, T. Gustafsson, and E. Blomstrand Repeated resistance exercise training induces different changes in mRNA expression of MAFbx and MuRF-1 in human skeletal muscle Am J Physiol Endocrinol Metab, January 1, 2008; 294(1): E43 - E51. [Abstract] [Full Text] [PDF]

				A. Nedergaard, K. Vissing, K. Overgaard, M. Kjaer, and P. Schjerling Expression patterns of atrogenic and ubiquitin proteasome component genes with exercise: effect of different loading patterns and repeated exercise bouts J Appl Physiol, November 1, 2007; 103(5): 1513 - 1522. [Abstract] [Full Text] [PDF]

				M. C. Kostek, Y.-W. Chen, D. J. Cuthbertson, R. Shi, M. J. Fedele, K. A. Esser, and M. J. Rennie Gene expression responses over 24 h to lengthening and shortening contractions in human muscle: major changes in CSRP3, MUSTN1, SIX1, and FBXO32 Physiol Genomics, September 11, 2007; 31(1): 42 - 52. [Abstract] [Full Text] [PDF]

				K. Evans, Z. Nasim, J. Brown, H. Butler, S. Kauser, H. Varoqui, J. D. Erickson, T. P. Herbert, and A. Bevington Acidosis-Sensing Glutamine Pump SNAT2 Determines Amino Acid Levels and Mammalian Target of Rapamycin Signalling to Protein Synthesis in L6 Muscle Cells J. Am. Soc. Nephrol., May 1, 2007; 18(5): 1426 - 1436. [Abstract] [Full Text] [PDF]

				J. Eliasson, T. Elfegoun, J. Nilsson, R. Kohnke, B. Ekblom, and E. Blomstrand Maximal lengthening contractions increase p70 S6 kinase phosphorylation in human skeletal muscle in the absence of nutritional supply Am J Physiol Endocrinol Metab, December 1, 2006; 291(6): E1197 - E1205. [Abstract] [Full Text] [PDF]

				H. C. Dreyer, S. Fujita, J. G. Cadenas, D. L. Chinkes, E. Volpi, and B. B. Rasmussen Resistance exercise increases AMPK activity and reduces 4E-BP1 phosphorylation and protein synthesis in human skeletal muscle J. Physiol., October 15, 2006; 576(2): 613 - 624. [Abstract] [Full Text] [PDF]