Linked Life Data

21406613

Source:http://linkedlifedata.com/resource/pubmed/id/21406613

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
2011-5-26
pubmed:abstractText
It is unclear whether the muscle hypertrophy induced by loss of myostatin signaling in mature muscles is maintained only by increased protein synthesis or whether reduced proteolysis contributes. To address this issue, we depleted myostatin by activating Cre recombinase for 2 wk in mature mice in which Mstn exon 3 was flanked by loxP sequences. The rate of phenylalanine tracer incorporation into myofibrillar proteins was determined 2, 5, and 24 wk after Cre activation ended. At all of these time points, myostatin-deficient mice had increased gastrocnemius and quadriceps muscle mass (?27%) and increased myofibrillar synthesis rate per gastrocnemius muscle (?19%) but normal myofibrillar synthesis rates per myofibrillar mass or RNA mass. Mean fractional myofibrillar degradation rates (estimated from the difference between rate of synthesis and rate of change in myofibrillar mass) and muscle concentrations of free 3-methylhistidine (from actin and myosin degradation) were unaffected by myostatin knockout. Overnight food deprivation reduced myofibrillar synthesis and ribosomal protein S6 phosphorylation and increased concentrations of 3-methylhistidine, muscle RING finger-1 mRNA, and atrogin-1 mRNA. Myostatin depletion did not affect these responses to food deprivation. These data indicate that maintenance of the muscle hypertrophy caused by loss of myostatin is mediated by increased protein synthesis per muscle fiber rather than suppression of proteolysis.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
1522-1555
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
300
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
E993-E1001
pubmed:meshHeading
pubmed:year
2011
pubmed:articleTitle
Effect of postdevelopmental myostatin depletion on myofibrillar protein metabolism.
pubmed:affiliation
Department of Medicine, Division of Endocrinology and Metabolism, University of Rochester, Rochester, NY 14642, USA. stephen_welle@urmc.rochester.edu
pubmed:publicationType
Journal Article, In Vitro, Research Support, N.I.H., Extramural