Faculty Opinions recommendation of Myogenic Progenitor Cells Control Extracellular Matrix Production by Fibroblasts during Skeletal Muscle Hypertrophy.

Abstract

Satellite cells, the predominant stem cell population in adult skeletal muscle, are activated in response to hypertrophic stimuli and give rise to myogenic progenitor cells (MPCs) within the extracellular matrix (ECM) that surrounds myofibers. This ECM is composed largely of collagens secreted by interstitial fibrogenic cells, which influence satellite cell activity and muscle repair during hypertrophy and aging. Here we show that MPCs interact with interstitial fibrogenic cells to ensure proper ECM deposition and optimal muscle remodeling in response to hypertrophic stimuli. MPC-dependent ECM remodeling during the first week of a growth stimulus is sufficient to ensure long-term myofiber hypertrophy. MPCs secrete exosomes containing miR-206, which represses Rrbp1, a master regulator of collagen biosynthesis, in fibrogenic cells to prevent excessive ECM deposition. These findings provide insights into how skeletal stem and progenitor cells interact with other cell types to actively regulate their extracellular environments for tissue maintenance and adaptation.Copyright © 2017 Elsevier Inc. All rights reserved. PMID: 27840022 Funding information This work was supported by: NIA NIH HHS, United States Grant ID: R01 AG049806 NCATS NIH HHS, United States Grant ID: UL1 TR001998 NIA NIH HHS, United States Grant ID: P30 AG024832 NIAMS NIH HHS, United States Grant ID: R01 AR060701 NIAMS NIH HHS, United States Grant ID: F32 AR065337 NIA NIH HHS, United States Grant ID: R21 AG034453 NCATS NIH HHS, United States Grant ID: UL1 TR000117 More Less keyboard_arrow_down