title: Regulation of skeletal muscle stem cells by fibroblast growth factors.
abstract: Fibroblast growth factors (FGFs) are essential for self-renewal of skeletal muscle stem cells (satellite cells) and required for maintenance and repair of skeletal muscle. Satellite cells express high levels of FGF receptors 1 and 4, low levels of FGF receptor 3, and little or no detectable FGF receptor 2. Of the multiple FGFs that influence satellite cell function in culture, FGF2 and FGF6 are the only members that regulate satellite cell function in vivo by activating ERK MAPK, p38α/β MAPKs, PI3 kinase, PLCγ and STATs. Regulation of FGF signaling is complex in satellite cells, requiring Syndecan-4, a heparan sulfate proteoglycan, as well as ß1-integrin and fibronectin. During aging, reduced responsiveness to FGF diminishes satellite cell self-renewal, leading to impaired skeletal muscle regeneration and depletion of satellite cells. Mislocalization of ß1-integrin, reductions in fibronectin, and alterations in heparan sulfate content all contribute to reduced FGF responsiveness in satellite cells. How these cell surface proteins regulate satellite cell self-renewal is incompletely understood. Here we summarize the current knowledge, highlighting the role(s) for FGF signaling in skeletal muscle regeneration, satellite cell behavior, and age-induced muscle wasting. Developmental Dynamics 246:359-367, 2017. © 2017 Wiley Periodicals, Inc.
authors.affiliation: Department of Molecular, Cellular, and Developmental Biology, University of Colorado, Boulder, Colorado.
authors.forename: Bradley
authors.initials: B
authors.lastname: Pawlikowski
authors.affiliation: Department of Molecular, Cellular, and Developmental Biology, University of Colorado, Boulder, Colorado.
authors.forename: Thomas Orion
authors.initials: TO
authors.lastname: Vogler
authors.affiliation: Department of Molecular, Cellular, and Developmental Biology, University of Colorado, Boulder, Colorado.
authors.forename: Katherine
authors.initials: K
authors.lastname: Gadek
authors.affiliation: Department of Molecular, Cellular, and Developmental Biology, University of Colorado, Boulder, Colorado.
authors.forename: Bradley B
authors.identifier: 0000-0001-6977-2509
authors.initials: BB
authors.lastname: Olwin
mesh_terms: D000375:Aging; D000818:Animals; D000066673:Cell Self Renewal; D005346:Fibroblast Growth Factors / Q000378:metabolism* / Q000502:physiology; D006801:Humans; D018482:Muscle, Skeletal / Q000166:cytology*; D032496:Satellite Cells, Skeletal Muscle / Q000502:physiology*; D015398:Signal Transduction; D013234:Stem Cells
chemical_list: D005346:Fibroblast Growth Factors
keywords: FGF; regeneration; satellite cell; skeletal muscle; stem cell