Please use this identifier to cite or link to this item:
Appears in Collections:Faculty of Health Sciences and Sport Journal Articles
Peer Review Status: Refereed
Title: Muscle satellite cells increase during hibernation in ground squirrels
Author(s): Brooks, Naomi
Myburgh, Kathryn H
Storey, Kenneth B
Contact Email:
Keywords: Myonuclei
Myogenic regulatory factors (MRFs)
Issue Date: Nov-2015
Date Deposited: 16-Dec-2015
Citation: Brooks N, Myburgh KH & Storey KB (2015) Muscle satellite cells increase during hibernation in ground squirrels. Comparative Biochemistry and Physiology - Part B: Biochemistry and Molecular Biology, 189, pp. 55-61.
Abstract: Skeletal muscle satellite cells (SCs) are involved in muscle growth and repair. However, clarification of their behavior in hibernating mammals is lacking. The aim of this study was to quantify SCs and total myonuclei in hibernator muscle during different phases of the torpor-arousal cycle. Skeletal muscle was collected from thirteen-lined ground squirrels,Ictidomys tridecemlineatus, at five timepoints during hibernation: control euthermic [CON, stable body temperature (Tb)], early torpor (ET, within 24h), late torpor (LT, 5+ consecutive days), early arousal (EA, increased respiratory rate >60 breaths/min, Tb 9–12°C) and interbout arousal (IA, euthermic Tb). Protein levels of p21, Myf5, Wnt4, and β-catenin were determined by western blotting. SCs (Pax7+) and myonuclei were identified using immunohistochemistry. Over the torpor–arousal cycle, myonuclei/fiber remained unchanged. However, the percentage of SCs increased significantly during ET (7.35±1.04% vs. control: 4.18±0.58%; p<0.05) and returned to control levels during LT. This coincided with a 224% increase in p21 protein during ET. Protein levels of Wnt4 did not change throughout, whereas Myf5 was lower during EA (p<0.08) and IA (p<0.05). Compared to torpor, β-catenin increased by 247% and 279% during EA and IA, respectively (p<0.05). In conclusion, SCs were not dormant during hibernation and increased numbers of SC during ET corresponded with elevated amounts of p21 suggesting that cell cycle control may explain the SC return to baseline levels during late torpor. Despite relatively low Tb during early arousal, active control of quiescence by Myf5 is reduced.
DOI Link: 10.1016/j.cbpb.2015.07.006
Rights: The publisher does not allow this work to be made publicly available in this Repository. Please use the Request a Copy feature at the foot of the Repository record to request a copy directly from the author. You can only request a copy if you wish to use this work for your own research or private study.
Licence URL(s):

Files in This Item:
File Description SizeFormat 
Brooks Myburgh Storey CBPB 2015.pdfFulltext - Published Version949.42 kBAdobe PDFUnder Embargo until 2999-12-27    Request a copy

Note: If any of the files in this item are currently embargoed, you can request a copy directly from the author by clicking the padlock icon above. However, this facility is dependent on the depositor still being contactable at their original email address.

This item is protected by original copyright

Items in the Repository are protected by copyright, with all rights reserved, unless otherwise indicated.

The metadata of the records in the Repository are available under the CC0 public domain dedication: No Rights Reserved

If you believe that any material held in STORRE infringes copyright, please contact providing details and we will remove the Work from public display in STORRE and investigate your claim.