Linked Life Data

18703409

Source:http://linkedlifedata.com/resource/pubmed/id/18703409

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
2008-10-3
pubmed:abstractText
To gain insight into the significance of alterations in the proteasome pathway for sarcopenia and its attenuation by calorie restriction, we examined protein oxidation and components of the proteasome pathway in plantaris muscle in 8-, 30-, and 35-mo-old ad libitum-fed (AL) rats; and in 8-, 35-, and 40-mo-old calorie-restricted (CR) rats. We hypothesized that CR rats would exhibit a lesser accumulation of protein carbonyls with aging and that this would be associated with a better maintenance of skeletal muscle proteasome activity and function with aging. Consistent with this view, whereas AL rats had a significant increase in protein carbonylation with aging, there was no such increase in CR rats. Protein levels of the ubiquitin ligases MuRF1 and MAFbx increased similarly with aging in both AL and CR rats. On the other hand, chymotrypsin-like activity of the proteasome increased with aging more gradually in CR rats, and this increase was paralleled by increases in the expression of the C2 subunit in both groups, suggesting that differences in activity were not related to differences in proteasome function with aging. Interestingly, the plot of muscle mass vs. proteasome activity showed that the oldest animals in both diets had a lower muscle mass than would be predicted by their proteasome activity, suggesting that other factors explain the acceleration of sarcopenia at advanced age. Since calorie restriction better protects skeletal muscle function than muscle mass with aging (Hepple RT, Baker DJ, Kaczor JJ, Krause DJ, FASEB J 19: 1320-1322, 2005), and our current results show that this protection of function is associated with a prevention of oxidative protein damage accumulation, we suggest that calorie restriction optimizes the proteasome pathway to preserve skeletal muscle function at the expense of modest muscle atrophy.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0363-6119
pubmed:author
pubmed:issnType
Print
pubmed:volume
295
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
R1231-7
pubmed:meshHeading
pubmed-meshheading:18703409-Age Factors, pubmed-meshheading:18703409-Aging, pubmed-meshheading:18703409-Animals, pubmed-meshheading:18703409-Body Weight, pubmed-meshheading:18703409-Caloric Restriction, pubmed-meshheading:18703409-Male, pubmed-meshheading:18703409-Muscle, Skeletal, pubmed-meshheading:18703409-Muscle Proteins, pubmed-meshheading:18703409-Muscular Atrophy, pubmed-meshheading:18703409-Proteasome Endopeptidase Complex, pubmed-meshheading:18703409-Protein Carbonylation, pubmed-meshheading:18703409-Protein Subunits, pubmed-meshheading:18703409-Rats, pubmed-meshheading:18703409-Rats, Inbred F344, pubmed-meshheading:18703409-SKP Cullin F-Box Protein Ligases, pubmed-meshheading:18703409-Signal Transduction, pubmed-meshheading:18703409-Time Factors, pubmed-meshheading:18703409-Ubiquitin-Protein Ligases
pubmed:year
2008
pubmed:articleTitle
Caloric restriction optimizes the proteasome pathway with aging in rat plantaris muscle: implications for sarcopenia.
pubmed:affiliation
Faculty of Kinesiology, Univ. of Calgary, 2500 Univ. Dr. NW, Calgary, AB, Canada T2N 1N4. hepple@ucalgary.ca
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't