Protein turnover in atrophying muscle: from nutritional intervention to microarray expression analysis.
OBJECTIVE
In response to decreased usage, skeletal muscle undergoes adaptive reductive remodeling due to the decrease in tension on the weight bearing components of the musculo-skeletal system. This response occurs with uncomplicated disuse (e.g. bed rest, space flight), as a secondary consequence of several widely prevalent chronic diseases for which activity is reduced (e.g. chronic obstructive pulmonary disease and chronic heart failure) and is part of the aging process. The problem is therefore one of considerable clinical importance.


RESULTS
The impaired function and exercise intolerance is related more to the associated muscle wasting rather than to the specific organ system primarily impacted by the disease. Progress has continued in describing the use of anabolic drugs and dietary manipulation. The major advance in the field has been: (i) the discovery of the atrogin-1 gene and (ii) the application of microarray expression analysis and proteomics with the objectives of obtaining comprehensive understanding of the pathways changed with disuse atrophy.


CONCLUSIONS
Disuse atrophy is a common clinical problem. There is a need for therapeutic interventions that do not involve exercise. A better understanding of the changes, particularly at the molecular level, could indicate hitherto unsuspected sites for nutritional and pharmacological intervention.
Stein
T Peter
TP
Department of Surgery, University of Medicine and Dentistry of New Jersey - SOM, 2 Medical Center Drive, Stratford, NJ 08084, USA. tpstein@umdnj.edu
Wade
Charles E
CE
D017079:Exercise Tolerance; D006801:Humans; D009124:Muscle Proteins / Q000096:biosynthesis / Q000378:metabolism*; D018482:Muscle, Skeletal / Q000378:metabolism*; D009133:Muscular Atrophy / Q000378:metabolism* / Q000503:physiopathology; D020411:Oligonucleotide Array Sequence Analysis
D009124:Muscle Proteins