title: Laminin-111 improves skeletal muscle stem cell quantity and function following eccentric exercise.
abstract: Laminin-111 (α1, β1, γ1; LM-111) is an important component of the extracellular matrix that is required for formation of skeletal muscle during embryonic development. Recent studies suggest that LM-111 supplementation can enhance satellite cell proliferation and muscle function in mouse models of muscular dystrophy. The purpose of this study was to determine the extent to which LM-111 can alter satellite and nonsatellite stem cell quantity following eccentric exercise-induced damage in young adult, healthy mice. One week following injection of LM-111 or saline, mice either remained sedentary or were subjected to a single bout of downhill running (EX). While one muscle was preserved for evaluation of satellite cell number, the other muscle was processed for isolation of mesenchymal stem cells (MSCs; Sca-1+CD45-) via FACS at 24 hours postexercise. Satellite cell number was approximately twofold higher in LM-111/EX compared with all other groups (p<.05), and the number of satellite cells expressing the proliferation marker Ki67 was 50% to threefold higher in LM-111/EX compared with all other groups (p<.05). LM-111 also increased the quantity of embryonic myosin heavy chain-positive (eMHC+) fibers in young mice after eccentric exercise (p<.05). Although MSC percentage and number were not altered, MSC proinflammatory gene expression was decreased, and hepatocyte growth factor gene expression was increased in the presence of LM-111 (p<.05). Together, these data suggest that LM-111 supplementation provides a viable solution for increasing skeletal muscle stem cell number and/or function, ultimately allowing for improvements in the regenerative response to eccentric exercise.
authors.affiliation: Department of Kinesiology and Community Health, Beckman Institute for Advanced Science and Technology, and Division of Biomedical Sciences, University of Illinois, Urbana, Illinois, USA.
authors.forename: Kai
authors.initials: K
authors.lastname: Zou
authors.affiliation: Department of Kinesiology and Community Health, Beckman Institute for Advanced Science and Technology, and Division of Biomedical Sciences, University of Illinois, Urbana, Illinois, USA.
authors.forename: Michael
authors.initials: M
authors.lastname: De Lisio
authors.affiliation: Department of Kinesiology and Community Health, Beckman Institute for Advanced Science and Technology, and Division of Biomedical Sciences, University of Illinois, Urbana, Illinois, USA.
authors.forename: Heather D
authors.initials: HD
authors.lastname: Huntsman
authors.affiliation: Department of Kinesiology and Community Health, Beckman Institute for Advanced Science and Technology, and Division of Biomedical Sciences, University of Illinois, Urbana, Illinois, USA.
authors.forename: Yair
authors.initials: Y
authors.lastname: Pincu
authors.affiliation: Department of Kinesiology and Community Health, Beckman Institute for Advanced Science and Technology, and Division of Biomedical Sciences, University of Illinois, Urbana, Illinois, USA.
authors.forename: Ziad
authors.initials: Z
authors.lastname: Mahmassani
authors.affiliation: Department of Kinesiology and Community Health, Beckman Institute for Advanced Science and Technology, and Division of Biomedical Sciences, University of Illinois, Urbana, Illinois, USA.
authors.forename: Matthew
authors.initials: M
authors.lastname: Miller
authors.affiliation: Department of Kinesiology and Community Health, Beckman Institute for Advanced Science and Technology, and Division of Biomedical Sciences, University of Illinois, Urbana, Illinois, USA.
authors.forename: Dami
authors.initials: D
authors.lastname: Olatunbosun
authors.affiliation: Department of Kinesiology and Community Health, Beckman Institute for Advanced Science and Technology, and Division of Biomedical Sciences, University of Illinois, Urbana, Illinois, USA.
authors.forename: Tor
authors.initials: T
authors.lastname: Jensen
authors.affiliation: Department of Kinesiology and Community Health, Beckman Institute for Advanced Science and Technology, and Division of Biomedical Sciences, University of Illinois, Urbana, Illinois, USA mboppart@illinois.edu.
authors.forename: Marni D
authors.initials: MD
authors.lastname: Boppart
mesh_terms: D000818:Animals; D015153:Blotting, Western; D005260:Female; D007150:Immunohistochemistry; D007797:Laminin / Q000494:pharmacology*; D051379:Mice; D008810:Mice, Inbred C57BL; D018482:Muscle, Skeletal / Q000166:cytology* / Q000187:drug effects; D010805:Physical Conditioning, Animal / Q000502:physiology*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D032496:Satellite Cells, Skeletal Muscle / Q000166:cytology* / Q000187:drug effects; D013234:Stem Cells / Q000166:cytology* / Q000187:drug effects
chemical_list: D007797:Laminin
keywords: Downhill running; Hepatocyte growth factor (HGF); Mesenchymal stem cells; Repair; Satellite cells