1. Cell Biology
  2. Stem Cells and Regenerative Medicine
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Inducible depletion of adult skeletal muscle stem cells impairs the regeneration of neuromuscular junctions

  1. Wenxuan Liu
  2. Lan Wei-LaPierre
  3. Alanna Klose
  4. Robert T Dirksen
  5. Joe V Chakkalakal  Is a corresponding author
  1. University of Rochester Medical Center, United States
Research Article
  • Cited 65
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Cite this article as: eLife 2015;4:e09221 doi: 10.7554/eLife.09221

Abstract

Skeletal muscle maintenance depends on motor innervation at neuromuscular junctions (NMJs). Multiple mechanisms contribute to NMJ repair and maintenance; however muscle stem cells (satellite cells, SCs), are deemed to have little impact on these processes. Therefore, the applicability of SC studies to attenuate muscle loss due to NMJ deterioration as observed in neuromuscular diseases and aging is ambiguous. We employed mice with an inducible Cre, and conditionally expressed DTA to deplete or GFP to track SCs. We found SC depletion exacerbated muscle atrophy and type transitions connected to neuromuscular disruption. Also, elevated fibrosis and further declines in force generation were specific to SC depletion and neuromuscular disruption. Fate analysis revealed SC activity near regenerating NMJs. Moreover, SC depletion aggravated deficits in reinnervation and post-synaptic morphology at regenerating NMJs. Therefore, our results propose a mechanism whereby further NMJ and skeletal muscle decline ensues upon SC depletion and neuromuscular disruption.

Article and author information

Author details

  1. Wenxuan Liu

    Department of Orthopaedics and Rehabilitation, Center for Musculoskeletal Research, University of Rochester Medical Center, Rochester, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Lan Wei-LaPierre

    Department of Pharmacology and Physiology, University of Rochester Medical Center, Rochester, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Alanna Klose

    Department of Orthopaedics and Rehabilitation, Center for Musculoskeletal Research, University of Rochester Medical Center, Rochester, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Robert T Dirksen

    Department of Pharmacology and Physiology, University of Rochester Medical Center, Rochester, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Joe V Chakkalakal

    Department of Orthopaedics and Rehabilitation, Center for Musculoskeletal Research, University of Rochester Medical Center, Rochester, United States
    For correspondence
    joe_chakkalakal@urmc.rochester.edu
    Competing interests
    The authors declare that no competing interests exist.

Ethics

Animal experimentation: This study was performed in strict accordance with the recommendations in the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health. Work with mice was conducted in accordance with protocols approved by the University Committee on Animal Resources, University of Rochester Medical Center protocol(#101565/2013-002).

Reviewing Editor

  1. Amy J Wagers, Harvard University, United States

Publication history

  1. Received: June 4, 2015
  2. Accepted: August 26, 2015
  3. Accepted Manuscript published: August 27, 2015 (version 1)
  4. Version of Record published: September 23, 2015 (version 2)

Copyright

© 2015, Liu et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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