title: Exercise training has beneficial anti-atrophy effects by inhibiting oxidative stress-induced MuRF1 upregulation in rats with diabetes.
abstract: OBJECTIVE
  MuRF1 E3 ubiquitin ligase has been identified as a mediator of skeletal muscle wasting in various skeletal muscle atrophy models, and its expression is upregulated by oxidative stress. Exercise training could decrease oxidative stress and restore the atrophied skeletal muscle. Here, our aim was to investigate whether exercise training has any effect on MuRF1 expression in rats with diabetes.
  
  
  METHODS
  Rats with streptozotocin-induced diabetes were subjected to exercise training, after which oxidative stress was determined, and MuRF1 expression was analyzed by immunohistochemistry, real-time RT-PCR and Western blot analysis. In addition, we analyzed C2C12 myotubes in an in vitro model to examine the effects of oxidative stress on the protein levels of MuRF1 and myosin heavy chain (MHC).
  
  
  RESULTS
  While oxidative stress and MuRF1 expression were increased in rats with diabetes, exercise training diminished the skeletal muscle wasting in diabetic rats by decreasing oxidative stress and inhibiting MuRF1 expression at both the mRNA and protein levels. In addition, oxidative stress-induced MuRF1 upregulation promoted proteasome dependent degradation of the myosin heavy chain (MHC) in C2C12 myotubes.
  
  
  CONCLUSIONS
  Our study provides the first evidence that the beneficial anti-atrophy effects of exercise training on diabetes might be mediated by inhibiting oxidative stress-induced MuRF1 upregulation and preventing MuRF1-mediated degradation of MHC.
authors.affiliation: Department of Health Science, Wuhan Institute of Physical Education, Luoyu Road No. 461, Wuhan City, Hubei Province, China.
authors.forename: Guo-Qing
authors.initials: GQ
authors.lastname: Chen
authors.forename: Cai-Ying
authors.initials: CY
authors.lastname: Mou
authors.forename: Yue-Qin
authors.initials: YQ
authors.lastname: Yang
authors.forename: Song
authors.initials: S
authors.lastname: Wang
authors.forename: Zhi-Wei
authors.initials: ZW
authors.lastname: Zhao
mesh_terms: D000818:Animals; D015153:Blotting, Western; D003921:Diabetes Mellitus, Experimental / Q000378:metabolism*; D007150:Immunohistochemistry; D018485:Muscle Fibers, Skeletal / Q000378:metabolism; D009124:Muscle Proteins / Q000378:metabolism*; D009133:Muscular Atrophy / Q000517:prevention & control*; D018995:Myosin Heavy Chains / Q000378:metabolism; D018384:Oxidative Stress / Q000502:physiology*; D010805:Physical Conditioning, Animal / Q000502:physiology*; D051381:Rats; D020133:Reverse Transcriptase Polymerase Chain Reaction; D000070584:Tripartite Motif Proteins; D044767:Ubiquitin-Protein Ligases / Q000378:metabolism*; D015854:Up-Regulation / Q000502:physiology*
chemical_list: D009124:Muscle Proteins; D000070584:Tripartite Motif Proteins; C499086:Trim63 protein, rat; D044767:Ubiquitin-Protein Ligases; D018995:Myosin Heavy Chains