TitleAge effect on myocellular remodeling: response to exercise and nutrition in humans.
Publication TypeJournal Article
Year of Publication2012
AuthorsIrving, BA, Robinson, MM, K Nair, S
JournalAgeing Res Rev
Volume11
Issue3
Pagination374-89
Date Published2012 Jul
ISSN1872-9649
KeywordsAging, Animals, Exercise, Humans, Muscle Fibers, Skeletal, Muscle, Skeletal, Nutritional Status, Postprandial Period, Protein Biosynthesis
Abstract

Aging is associated with decline in muscle mass and muscle functions. Muscle strength declines disproportionate to the decline in muscle mass indicating that muscle quality or protein quality also declines with age. Human studies have shown a progressive decline in muscle protein synthesis including proteins in the contractile apparatus and mitochondria with age. However, the decline in muscle protein synthesis is disproportionate to the decline in muscle mass that occurs with age prompting to hypothesize that muscle protein degradation also declines with age. A decline in mitochondrial capacity to synthesize ATP is likely a limiting factor of both synthesis and degradation, which are ATP dependent processes. In support of the above hypothesis, several studies have shown a decline in whole body protein turnover (synthesis and degradation). The timely and efficient degradation of irreversibly damaged or modified proteins is critical to maintain the quality of protein. It is proposed that a failure to degrade the damaged proteins and replacing them with newly synthesized proteins contribute to age related decline in muscle mass and quality of muscle proteins. The underlying molecular mechanism of these age related changes in human muscle needs further investigation.

DOI10.1016/j.arr.2011.11.001
Alternate JournalAgeing Res. Rev.
PubMed ID22085885
PubMed Central IDPMC3309175
Grant ListR01 DK041973 / DK / NIDDK NIH HHS / United States
R01-DK41973 / DK / NIDDK NIH HHS / United States
UL1-RR-024150-01 / RR / NCRR NIH HHS / United States
P30 DK050456 / DK / NIDDK NIH HHS / United States
R01 DK041973-10 / DK / NIDDK NIH HHS / United States
T32 DK007352-32 / DK / NIDDK NIH HHS / United States
R01 AG009531-08 / AG / NIA NIH HHS / United States
KL2 RR024151 / RR / NCRR NIH HHS / United States
AG09531 / AG / NIA NIH HHS / United States
T32 DK007352 / DK / NIDDK NIH HHS / United States
5T32DK007352-32 / DK / NIDDK NIH HHS / United States
UL1 RR024150 / RR / NCRR NIH HHS / United States
R01 AG009531 / AG / NIA NIH HHS / United States
KL2 RR024151-06 / RR / NCRR NIH HHS / United States
UL1 RR024150-01 / RR / NCRR NIH HHS / United States