title: Unchanged Neurotrophic Factors and Their Receptors Correlate With Sparing in Extraocular Muscles in Amyotrophic Lateral Sclerosis.
abstract: To investigate the impact of amyotrophic lateral sclerosis (ALS) on the extraocular muscles (EOMs) by examining the distribution of neurotrophic factors (NTFs) and their receptors in EOMs and limb muscles from ALS transgenic mice.
  
  
  
  Muscle samples collected from transgenic mice overexpressing human superoxide dismutase type 1 mutations (SOD1G93A, the most widely used mouse model of ALS) at 50 and 150 days as well as age-matched controls were analyzed with immunohistochemistry using antibodies against brain-derived neurotrophic factor (BDNF), neurotrophin-3 (NT-3), neurotrophin-4/5 (NT-4), glial cell line-derived neurotrophic factor (GDNF), and the neurotrophin receptors p75NTR, tyrosine kinase (Trk) receptor TrkB and TrkC, and GDNF family receptor alpha-1 (GFRα-1).
  
  
  
  There was an intrinsic difference in NTF expression between EOMs and limb muscles in control mice: EOMs presented significantly lower number of neuromuscular junctions (NMJs) labeled for BDNF and NT-4 at 50 days, and for BDNF and GDNF at 150 days, compared with the control limb muscles of corresponding age. In ALS transgenic mice at 150 days, NTF expression in limb muscles was significantly changed but not in EOMs: the limb muscles presented a significant decline in the number of NMJs labeled for BDNF, NT-4, GDNF, p75NTR, TrkB, and TrkC, which was not observed in EOMs.
  
  
  
  The significant differences in expression of NTFs on NMJs between EOMs and limb muscles in both control and ALS transgenic mice suggest that NTF may be involved in the pathogenesis of ALS and the resistance of EOMs to the disease.
authors.affiliation: Department of Integrative Medical Biology, Section for Anatomy, Umeå University, Umeå, Sweden 2Department of Clinical Sciences, Ophthalmology, Umeå University, Umeå, Sweden.
authors.forename: Vahid M
authors.initials: VM
authors.lastname: Harandi
authors.affiliation: Department of Clinical Sciences, Ophthalmology, Umeå University, Umeå, Sweden.
authors.forename: Aida R N
authors.initials: AR
authors.lastname: Gaied
authors.affiliation: Department of Medical Biosciences, Pathology, Umeå University, Umeå, Sweden.
authors.forename: Thomas
authors.initials: T
authors.lastname: Brännström
authors.affiliation: Department of Integrative Medical Biology, Section for Anatomy, Umeå University, Umeå, Sweden 2Department of Clinical Sciences, Ophthalmology, Umeå University, Umeå, Sweden.
authors.forename: Fatima
authors.initials: F
authors.lastname: Pedrosa Domellöf
authors.affiliation: Department of Integrative Medical Biology, Section for Anatomy, Umeå University, Umeå, Sweden.
authors.forename: Jing-Xia
authors.initials: JX
authors.lastname: Liu
mesh_terms: D000690:Amyotrophic Lateral Sclerosis / Q000378:metabolism* / Q000473:pathology; D000818:Animals; D002460:Cell Line; D004195:Disease Models, Animal; D006801:Humans; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D009046:Motor Neurons / Q000378:metabolism; D018482:Muscle, Skeletal / Q000378:metabolism* / Q000473:pathology; D009414:Nerve Growth Factors / Q000378:metabolism*; D009469:Neuromuscular Junction / Q000378:metabolism; D009801:Oculomotor Muscles / Q000378:metabolism* / Q000473:pathology; D017475:Receptors, Nerve Growth Factor / Q000378:metabolism*
chemical_list: D009414:Nerve Growth Factors; D017475:Receptors, Nerve Growth Factor