Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
1999-12-22
pubmed:abstractText
Eccentric contractions require the lengthening of skeletal muscle during force production and result in acute and prolonged muscle injury. Because a variety of stressors, including physical exercise and injury, can result in the activation of the c-Jun NH(2)-terminal kinase (JNK) intracellular signaling cascade in skeletal muscle, we investigated the effects of eccentric exercise on the activation of this stress-activated protein kinase in human skeletal muscle. Twelve healthy subjects (7 men, 5 women) completed maximal concentric or eccentric knee extensions on a KinCom isokinetic dynamometer (10 sets, 10 repetitions). Percutaneous needle biopsies were obtained from the vastus lateralis muscle 24 h before exercise (basal), immediately postexercise, and 6 h postexercise. Whereas both forms of exercise increased JNK activity immediately postexercise, eccentric contractions resulted in a much higher activation (15.4 +/- 4.5 vs. 3.5 +/- 1.4-fold increase above basal, eccentric vs. concentric). By 6 h after exercise, JNK activity decreased back to baseline values. In contrast to the greater activation of JNK with eccentric exercise, the mitogen-activated protein kinase kinase 4, the immediate upstream regulator of JNK, was similarly activated by concentric and eccentric exercise. Because the activation of JNK promotes the phosphorylation of a variety of transcription factors, including c-Jun, the results from this study suggest that JNK may be involved in the molecular and cellular adaptations that occur in response to injury-producing exercise in human skeletal muscle.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
8750-7587
pubmed:author
pubmed:issnType
Print
pubmed:volume
87
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1668-73
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed:year
1999
pubmed:articleTitle
Eccentric exercise markedly increases c-Jun NH(2)-terminal kinase activity in human skeletal muscle.
pubmed:affiliation
Research Division, Joslin Diabetes Center, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Massachusetts 02111, USA.
pubmed:publicationType
Journal Article, Clinical Trial, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't