title: Cyclic mechanical stress suppresses myogenic differentiation of adult bovine satellite cells through activation of extracellular signal-regulated kinase.
abstract: Mechanical stress leads to satellite cell activation, which is an important event in the development, growth, and remodeling of postnatal skeletal muscle. Although there is a considerable knowledge on the events involved in skeletal muscle regeneration and development, the precise role of mechanical stress on activation of satellite cells remains unclear. Previously, satellite cells were isolated from adult bovine muscle and it was shown that the cells are multipotent, i.e., capable of proliferating and to differentiating into both myoblasts and adipocytes. This study investigated the cellular mechanisms by which cyclic mechanical stretching modulates the proliferation and differentiation of adult bovine satellite cells. The application of cyclic stretch induced the proliferation of satellite cells and inhibited their differentiation into myotubes. This response is believed to be closely related to the stretch-mediated changes in the expression of myogenic and cell cycle regulatory factors. Cyclic stretching increased the level of extracellular signal-regulated kinase (ERK) phosphorylation, whereas a specific ERK inhibitor (PD98058) blocked the stretch-mediated inhibition of myogenesis in a dose-dependent manner. Overall, this study demonstrates for the first time that cyclic mechanical stretch induces the proliferation of bovine satellite cells and suppresses their myogenic differentiation through the activation of ERK.
authors.affiliation: Division of Biological Sciences, Chonbuk National University, Jeonju 561-756, Korea.
authors.forename: Sung-Ho
authors.initials: SH
authors.lastname: Kook
authors.forename: Young-Ok
authors.initials: YO
authors.lastname: Son
authors.forename: Ki-Choon
authors.initials: KC
authors.lastname: Choi
authors.forename: Hyun-Jeong
authors.initials: HJ
authors.lastname: Lee
authors.forename: Wan-Tae
authors.initials: WT
authors.lastname: Chung
authors.forename: In-Ho
authors.initials: IH
authors.lastname: Hwang
authors.forename: Jeong-Chae
authors.initials: JC
authors.lastname: Lee
mesh_terms: D000818:Animals; D002417:Cattle; D002453:Cell Cycle; D002454:Cell Differentiation; D002459:Cell Fusion; D049109:Cell Proliferation; D048430:Cell Shape; D019938:Cyclin D1 / Q000378:metabolism; D050760:Cyclin-Dependent Kinase Inhibitor p27 / Q000378:metabolism; D004789:Enzyme Activation; D005786:Gene Expression Regulation; D020935:MAP Kinase Signaling System; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism*; D048052:Mitogen-Activated Protein Kinase 3 / Q000378:metabolism*; D018485:Muscle Fibers, Skeletal / Q000166:cytology / Q000201:enzymology; D018006:Myogenic Regulatory Factors / Q000235:genetics / Q000378:metabolism; D018995:Myosin Heavy Chains / Q000235:genetics / Q000378:metabolism; D018809:Proliferating Cell Nuclear Antigen / Q000378:metabolism; D032496:Satellite Cells, Skeletal Muscle / Q000166:cytology* / Q000201:enzymology*; D013314:Stress, Mechanical
chemical_list: D018006:Myogenic Regulatory Factors; D018809:Proliferating Cell Nuclear Antigen; D019938:Cyclin D1; D050760:Cyclin-Dependent Kinase Inhibitor p27; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D018995:Myosin Heavy Chains