title: Changes in proliferation, differentiation, fibroblast growth factor 2 responsiveness and expression of syndecan-4 and glypican-1 with turkey satellite cell age.
abstract: Myogenic satellite cells are heterogeneous multipotential stem cells that are required for muscle repair, maintenance, and growth. The membrane-associated heparan sulfate proteoglycans syndecan-4 and glypican-1 differentially regulate satellite cell proliferation, differentiation, fibroblast growth factor 2 (FGF2) signal transduction, and expression of the myogenic regulatory factors MyoD and myogenin. The objective of the current study was to determine the effect of age on syndecan-4 and glypican-1 satellite cell populations, proliferation, differentiation, FGF2 responsiveness, and expression of syndecan-4, glypican-1, MyoD, and myogenin using satellite cells isolated from the pectoralis major muscle of 1-day-old, 7-week-old and 16-week-old turkeys. Proliferation was significantly reduced in the 16-week-old satellite cells, while differentiation was decreased in the 7-week-old and the 16-week-old cells beginning at 48 h of differentiation. Fibroblast growth factor 2 responsiveness was highest in the 1-day-old and 7-week-old cells during proliferation; during differentiation there was an age-dependent response to FGF2. Syndecan-4 and glypican-1 satellite cell populations decreased with age, but syndecan-4 and glypican-1 were differentially expressed with age during proliferation and differentiation. MyoD and myogenin mRNA expression was significantly decreased in 16-week-old cells compared to the 1-day-old and 7-week-old cells. MyoD and myogenin protein expression was higher during proliferation in the 16-week-old cells and decreased with differentiation. These data demonstrate an age-dependent effect on syndecan-4 and glypican-1 satellite cell subpopulations, which may be associated with age-related changes in proliferation, differentiation, FGF2 responsiveness, and the expression of the myogenic regulatory factors MyoD and myogenin.
authors.affiliation: Department of Animal Sciences, Ohio Agricultural Research and Development Center, The Ohio State University, Wooster, OH, USA.
authors.forename: Laura B
authors.initials: LB
authors.lastname: Harthan
authors.forename: Douglas C
authors.initials: DC
authors.lastname: McFarland
authors.forename: Sandra G
authors.initials: SG
authors.lastname: Velleman
mesh_terms: D000367:Age Factors; D000818:Animals; D000831:Animals, Newborn; D030161:Avian Proteins / Q000235:genetics / Q000378:metabolism; D015153:Blotting, Western; D002454:Cell Differentiation / Q000187:drug effects*; D049109:Cell Proliferation / Q000187:drug effects*; D002478:Cells, Cultured; D016222:Fibroblast Growth Factor 2 / Q000494:pharmacology*; D005434:Flow Cytometry; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects; D053673:Glypicans / Q000235:genetics* / Q000378:metabolism; D017570:MyoD Protein / Q000235:genetics / Q000378:metabolism; D018008:Myogenin / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D032496:Satellite Cells, Skeletal Muscle / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D053671:Syndecan-4 / Q000235:genetics* / Q000378:metabolism; D014422:Turkeys
chemical_list: D030161:Avian Proteins; D053673:Glypicans; D017570:MyoD Protein; D018008:Myogenin; D053671:Syndecan-4; D016222:Fibroblast Growth Factor 2