|
|
||||||||
Human Performance Laboratory, Ball State University, Muncie, Indiana
Submitted 26 June 2007 ; accepted in final form 28 August 2007
The aim of this study was to examine the time course induction of select proteolytic [muscle ring finger-1 (MuRF-1), atrogin-1, forkhead box 3A (FOXO3A), calpain-1, calpain-2], myostatin, and cytokine (IL -6, -8, -15, and TNF-
) mRNA after an acute bout of resistance (RE) or run (RUN) exercise. Six experienced RE (25 ± 4 yr, 74 ± 14 kg, 1.71 ± 0.11 m) and RUN (25 ± 4 yr, 72 ± 5 kg, 1.81 ± 0.07 m) subjects had muscle biopsies from the vastus lateralis (RE) or gastrocnemius (RUN) before, immediately after, and 1, 2, 4, 8, 12, and 24 h postexercise. RE increased (P < 0.05) mRNA expression of MuRF-1 early (3.5-fold, 1–4 h), followed by a decrease in atrogin-1 (3.3-fold) and FOXO3A (1.7-fold) 8–12 h postexercise. Myostatin mRNA decreased (6.3-fold; P < 0.05) from 1 to 24 h postexercise, whereas IL-6, IL-8, and TNF-
mRNA were elevated 2–12 h. RUN increased (P < 0.05) MuRF-1 (3.6-fold), atrogin-1 (1.6-fold), and FOXO3A (1.9-fold) 1–4 h postexercise. Myostatin was suppressed (3.6-fold; P < 0.05) 8–12 h post-RUN. The cytokines exhibited a biphasic response, with immediate elevation (P < 0.05) of IL-6, IL-8, and TNF-
, followed by a second elevation (P < 0.05) 2–24 h postexercise. In general, the timing of the gene induction indicated early elevation of proteolytic genes, followed by prolonged elevation of cytokines and suppression of myostatin. These data provide basic information for the timing of human muscle biopsy samples for gene expression studies involving exercise. Furthermore, this information suggests a greater induction of proteolytic genes following RUN compared with RE.
muscle ring finger-1; atrogin-1; myostatin; interleukin-6; interleukin-8
This article has been cited by other articles:
![]() |
S. Al-Majid and H. Waters The Biological Mechanisms of Cancer-Related Skeletal Muscle Wasting: The Role of Progressive Resistance Exercise Biol Res Nurs, July 1, 2008; 10(1): 7 - 20. [Abstract] [PDF] |
||||
![]() |
H. D. Kollias and J. C. McDermott Transforming growth factor-{beta} and myostatin signaling in skeletal muscle J Appl Physiol, March 1, 2008; 104(3): 579 - 587. [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] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |