title: Granulocyte colony-stimulating factor (G-CSF) positive effects on muscle fiber degeneration and gait recovery after nerve lesion in MDX mice.
abstract: BACKGROUND
  G-CSF has been shown to decrease inflammatory processes and to act positively on the process of peripheral nerve regeneration during the course of muscular dystrophy.
  
  
  OBJECTIVE
  The aims of this study were to investigate the effects of treatment of G-CSF during sciatic nerve regeneration and histological analysis in the soleus muscle in MDX mice.
  
  
  METHODS
  Six-week-old male MDX mice underwent left sciatic nerve crush and were G-CSF treated at 7 days prior to and 21 days after crush. Ten and twenty-one days after surgery, the mice were euthanized, and the sciatic nerves were processed for immunohistochemistry (anti-p75(NTR) and anti-neurofilament) and transmission electron microscopy. The soleus muscles were dissected out and processed for H&E staining and subsequent morphologic analysis. Motor function analyses were performed at 7 days prior to and 21 days after sciatic crush using the CatWalk system and the sciatic nerve index.
  
  
  RESULTS
  Both groups treated with G-CSF showed increased p75(NTR) and neurofilament expression after sciatic crush. G-CSF treatment decreased the number of degenerated and regenerated muscle fibers, thereby increasing the number of normal muscle fibers.
  
  
  CONCLUSIONS
  The reduction in p75(NTR) and neurofilament indicates a decreased regenerative capacity in MDX mice following a lesion to a peripheral nerve. The reduction in motor function in the crushed group compared with the control groups may reflect the cycles of muscle degeneration/regeneration that occur postnatally. Thus, G-CSF treatment increases motor function in MDX mice. Nevertheless, the decrease in baseline motor function in these mice is not reversed completely by G-CSF.
authors.affiliation: Departament of Structural and Functional Biology, Institute of Biology, University of Campinas (UNICAMP) CP 6109, CEP 13083-907, Campinas, SP, Brazil.
authors.forename: Gustavo F
authors.initials: GF
authors.lastname: Simões
authors.affiliation: Departament of Structural and Functional Biology, Institute of Biology, University of Campinas (UNICAMP) CP 6109, CEP 13083-907, Campinas, SP, Brazil.
authors.forename: Suzana U
authors.initials: SU
authors.lastname: Benitez
authors.affiliation: Departament of Structural and Functional Biology, Institute of Biology, University of Campinas (UNICAMP) CP 6109, CEP 13083-907, Campinas, SP, Brazil.
authors.forename: Alexandre L R
authors.initials: AL
authors.lastname: Oliveira
mesh_terms: D000818:Animals; D001369:Axons / Q000187:drug effects; D016022:Case-Control Studies; D004195:Disease Models, Animal; D005684:Gait / Q000187:drug effects; D016179:Granulocyte Colony-Stimulating Factor / Q000494:pharmacology*; D008297:Male; D051379:Mice; D018101:Mice, Inbred mdx; D018482:Muscle, Skeletal / Q000187:drug effects* / Q000293:injuries / Q000502:physiology; D009133:Muscular Atrophy / Q000188:drug therapy*; D009409:Nerve Crush; D009416:Nerve Regeneration / Q000187:drug effects*; D020127:Recovery of Function / Q000187:drug effects; D012584:Sciatic Nerve / Q000187:drug effects* / Q000293:injuries / Q000502:physiology; D020426:Sciatic Neuropathy / Q000188:drug therapy*; D016896:Treatment Outcome
chemical_list: D016179:Granulocyte Colony-Stimulating Factor
keywords: Axotomy; G-CSF; Schwann cell; muscular dystrophy