| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
ENVIRONMENTAL, EXERCISE AND RESPIRATORY PHYSIOLOGY
1Biochemistry of Aging Laboratory and Department of Aging and Geriatric Research, University of Florida, Gainesville, Florida; and Departments of 2Geriatrics and 3Physiology and Biophysics, University of Arkansas for Medical Sciences, Little Rock, Arkansas
Submitted 23 August 2004 ; accepted in final form 10 January 2005
Muscle atrophy is associated with a loss of muscle fiber nuclei, most likely through apoptosis. We investigated age-related differences in the extent of apoptosis in soleus muscle of young (6 mo) and old (32 mo) male Fischer 344 x Brown Norway rats subjected to acute disuse atrophy induced by 14 days of hindlimb suspension (HS). HS-induced atrophy (reduction in muscle weight and cross-sectional area) was associated with loss of myofiber nuclei in soleus muscle of young, but not old, rats. This resulted in a significant decrease in the myonuclear domain (cross-sectional area per nucleus) in young and old rats, with changes being more pronounced in old animals. Levels of apoptosis (TdT-mediated dUTP nick end labeling and DNA fragmentation) were higher in soleus muscles of old control rats than young animals. Levels were significantly increased with HS in young and old rats, with the greatest changes in old animals. Caspase-3 activity in soleus muscle tended to be increased with age, but changes were not statistically significant (P = 0.052). However, with HS, caspase-3 activity significantly increased in young, but not old, rats. Immunohistochemistry showed that the proapoptotic endonuclease G (EndoG, a mitochondrion-specific nuclease) was localized in the subsarcolemmal mitochondria in control muscles, and translocation to the nucleus occurred in old, but not young, control animals. There was no difference between EndoG total protein content in young and old control rats, but EndoG increased almost fivefold in soleus muscle of old, but not young, rats after HS. These results show that deregulation of myonuclear number occurs in old skeletal muscle and that the pathways involved in apoptosis are distinct in young and old muscles. Apoptosis in skeletal muscle is partly mediated by the subsarcolemmal mitochondria through EndoG translocation to the nucleus in response to HS.
hindlimb suspension; sarcopenia; nuclear apoptosis; caspase-3; endonuclease G; oxidative stress; aging
This article has been cited by other articles:
|
|
 |
|
  K. Gundersen and J. C. Bruusgaard Nuclear domains during muscle atrophy: nuclei lost or paradigm lost? J. Physiol., June 1, 2008; 586(11): 2675 - 2681. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 K. A. Huey, R. R. Roy, H. Zhong, and C. Lullo Time-dependent changes in caspase-3 activity and heat shock protein 25 after spinal cord transection in adult rats Exp Physiol, March 1, 2008; 93(3): 415 - 425. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 E. Marzetti, L. Groban, S. E. Wohlgemuth, H. A. Lees, M. Lin, H. Jobe, S. Giovannini, C. Leeuwenburgh, and C. S. Carter Effects of short-term GH supplementation and treadmill exercise training on physical performance and skeletal muscle apoptosis in old rats Am J Physiol Regulatory Integrative Comp Physiol, February 1, 2008; 294(2): R558 - R567. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
H. Degens, A. K. Swisher, Y. F. Heijdra, P. M. Siu, P. N. Richard Dekhuijzen, and S. E. Alway Apoptosis and Id2 expression in diaphragm and soleus muscle from the emphysematous hamster Am J Physiol Regulatory Integrative Comp Physiol, July 1, 2007; 293(1): R135 - R144. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 E. E. Pistilli, P. M. Siu, and S. E. Alway Interleukin-15 responses to aging and unloading-induced skeletal muscle atrophy Am J Physiol Cell Physiol, April 1, 2007; 292(4): C1298 - C1304. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
D. S. Perrien, N. S. Akel, E. E. Dupont-Versteegden, R. A. Skinner, E. R. Siegel, L. J. Suva, and D. Gaddy Aging alters the skeletal response to disuse in the rat Am J Physiol Regulatory Integrative Comp Physiol, February 1, 2007; 292(2): R988 - R996. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
E. E. Dupont-Versteegden, B. A. Strotman, C. M. Gurley, D. Gaddy, M. Knox, J. D. Fluckey, and C. A. Peterson Nuclear translocation of EndoG at the initiation of disuse muscle atrophy and apoptosis is specific to myonuclei Am J Physiol Regulatory Integrative Comp Physiol, December 1, 2006; 291(6): R1730 - R1740. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 E. E. Dupont-Versteegden, J. D. Fluckey, M. Knox, D. Gaddy, and C. A. Peterson Effect of flywheel-based resistance exercise on processes contributing to muscle atrophy during unloading in adult rats J Appl Physiol, July 1, 2006; 101(1): 202 - 212. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
K. Csukly, A. Ascah, J. Matas, P. F. Gardiner, E. Fontaine, and Y. Burelle Muscle denervation promotes opening of the permeability transition pore and increases the expression of cyclophilin D J. Physiol., July 1, 2006; 574(1): 319 - 327. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
F. Haddad and G. R. Adams Aging-sensitive cellular and molecular mechanisms associated with skeletal muscle hypertrophy J Appl Physiol, April 1, 2006; 100(4): 1188 - 1203. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
P. M. Siu, E. E. Pistilli, Z. Murlasits, and S. E. Alway Hindlimb unloading increases muscle content of cytosolic but not nuclear Id2 and p53 proteins in young adult and aged rats J Appl Physiol, March 1, 2006; 100(3): 907 - 916. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 R. T. Hepple Dividing to Keep Muscle Together: The Role of Satellite Cells in Aging Skeletal Muscle Sci. Aging Knowl. Environ., January 18, 2006; 2006(3): pe3 - pe3. [Abstract] [Full Text]
|
|
|
|
 |
|
 M. BAR-SHAI, E. CARMELI, and A. Z. REZNICK The Role of NF-{kappa}B in Protein Breakdown in Immobilization, Aging, and Exercise: From Basic Processes to Promotion of Health Ann. N.Y. Acad. Sci., December 1, 2005; 1057(1): 431 - 447. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
P. M. Siu and S. E. Alway Age-related apoptotic responses to stretch-induced hypertrophy in quail slow-tonic skeletal muscle Am J Physiol Cell Physiol, November 1, 2005; 289(5): C1105 - C1113. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
P. M. Siu, E. E. Pistilli, and S. E. Alway Apoptotic responses to hindlimb suspension in gastrocnemius muscles from young adult and aged rats Am J Physiol Regulatory Integrative Comp Physiol, October 1, 2005; 289(4): R1015 - R1026. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 P. M. Siu, E. E. Pistilli, M. J. Ryan, and S. E. Alway Aging Sustains the Hypertrophy-Associated Elevation of Apoptotic Suppressor X-Linked Inhibitor of Apoptosis Protein (XIAP) in Skeletal Muscle During Unloading J. Gerontol. A Biol. Sci. Med. Sci., August 1, 2005; 60(8): 976 - 983. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
P. M. Siu and S. E. Alway Mitochondria-associated apoptotic signalling in denervated rat skeletal muscle J. Physiol., May 15, 2005; 565(1): 309 - 323. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |
