Time course and spatial profile of Nogo-A expression in experimental autoimmune encephalomyelitis in C57BL/6 mice

J Neuropathol Exp Neurol. 2012 Oct;71(10):907-20. doi: 10.1097/NEN.0b013e31826caebe.

Abstract

Inhibition of the myelin-associated neurite outgrowth inhibitor Nogo-A has been found to be beneficial in experimental autoimmune encephalomyelitis (EAE), but there are little data on its expression dynamics during the disease course. We analyzed Nogo-A mRNA and protein during the course of EAE in 27 C57BL/6 mice and in 8 controls. Histopathologic and molecular analyses were performed on Day 0 (naive), preclinical (Day 10), acute (Days 18-22) and chronic (Day 50) time points. In situ hybridization and real-time polymerase chain reaction analyses revealed reduced Nogo-A mRNA expression at preclinical (p < 0.0001) and acute phases (p < 0.0001), followed by upregulation during the chronic phase (p < 0.0001). Nogo-A mRNA was expressed in neurons and oligodendrocytes. By immunohistochemistry and Western blot, there was increased Nogo-A protein expression (p < 0.001) in the chronic phase. Moreover, spatial differences were observed within EAE lesions. The pattern of Nogo-A protein expression inversely correlated with axonal regeneration growth-associated protein 43-positive axons (60% of which were Nogo-A contact-free during the acute phase) and axonal injury (β-amyloid precursor protein-positive axons). Cortical Nogo-66 receptor protein and mRNA levels increased during the chronic phase. The results indicate that Nogo-A and Nogo receptor are actively regulated in EAE lesions; this may indicate a specific time window for localized axonal regeneration in the acute phase of EAE.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acute Disease
  • Animals
  • Encephalomyelitis, Autoimmune, Experimental / genetics
  • Encephalomyelitis, Autoimmune, Experimental / metabolism*
  • Female
  • GPI-Linked Proteins / biosynthesis
  • GPI-Linked Proteins / genetics
  • Gene Expression Regulation*
  • Mice
  • Mice, Inbred C57BL
  • Myelin Proteins / biosynthesis*
  • Myelin Proteins / genetics
  • Neurons / metabolism
  • Nogo Proteins
  • Nogo Receptor 1
  • Oligodendroglia / metabolism
  • Receptors, Cell Surface / biosynthesis*
  • Receptors, Cell Surface / genetics
  • Time Factors

Substances

  • GPI-Linked Proteins
  • Myelin Proteins
  • Nogo Proteins
  • Nogo Receptor 1
  • Receptors, Cell Surface
  • Rtn4 protein, mouse
  • Rtn4r protein, mouse