Mechanical regulation of mitogen-activated protein kinase signaling in articular cartilage
Authors
Fanning, Paul J.Emkey, Gregory
Smith, Robert J.
Grodzinsky, Alan J.
Szasz, Nora
Trippel, Stephen B.
UMass Chan Affiliations
Department of Orthopedics and Physical RehabilitationDocument Type
Journal ArticlePublication Date
2003-09-04Keywords
AnimalsAnimals, Newborn
Biomechanics
Cartilage, Articular
Cattle
Insulin-Like Growth Factor I
JNK Mitogen-Activated Protein Kinases
MAP Kinase Signaling System
Mechanotransduction, Cellular
Mitogen-Activated Protein Kinase 3
Mitogen-Activated Protein Kinase Kinases
Mitogen-Activated Protein Kinases
Phosphorylation
Time Factors
p38 Mitogen-Activated Protein Kinases
Orthopedics
Rehabilitation and Therapy
Metadata
Show full item recordAbstract
Articular chondrocytes respond to mechanical forces by alterations in gene expression, proliferative status, and metabolic functions. Little is known concerning the cell signaling systems that receive, transduce, and convey mechanical information to the chondrocyte interior. Here, we show that ex vivo cartilage compression stimulates the phosphorylation of ERK1/2, p38 MAPK, and SAPK/ERK kinase-1 (SEK1) of the JNK pathway. Mechanical compression induced a phased phosphorylation of ERK consisting of a rapid induction of ERK1/2 phosphorylation at 10 min, a rapid decay, and a sustained level of ERK2 phosphorylation that persisted for at least 24 h. Mechanical compression also induced the phosphorylation of p38 MAPK in strictly a transient fashion, with maximal phosphorylation occurring at 10 min. Mechanical compression stimulated SEK1 phosphorylation, with a maximum at the relatively delayed time point of 1 h and with a higher amplitude than ERK1/2 and p38 MAPK phosphorylation. These data demonstrate that mechanical compression alone activates MAPK signaling in intact cartilage. In addition, these data demonstrate distinct temporal patterns of MAPK signaling in response to mechanical loading and to the anabolic insulin-like growth factor-I. Finally, the data indicate that compression coactivates distinct signaling pathways that may help define the nature of mechanotransduction in cartilage.Source
J Biol Chem. 2003 Dec 19;278(51):50940-8. Epub 2003 Sep 2. Link to article on publisher's siteDOI
10.1074/jbc.M305107200Permanent Link to this Item
http://hdl.handle.net/20.500.14038/43069PubMed ID
12952976Related Resources
Link to Article in PubMedae974a485f413a2113503eed53cd6c53
10.1074/jbc.M305107200
Scopus Count
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