Stem Cell Reviews and Reports

, Volume 10, Issue 4, pp 539–547

The synthetic NCAM mimetic peptide FGL mobilizes neural stem cells in vitro and in vivo

  • Rebecca Klein
  • Stefan Blaschke
  • Bernd Neumaier
  • Heike Endepols
  • Rudolf Graf
  • Meike Keuters
  • Joerg Hucklenbroich
  • Morten Albrechtsen
  • Stephen Rees
  • Gereon Rudolf Fink
  • Michael Schroeter
  • Maria Adele Rueger
Article

DOI: 10.1007/s12015-014-9512-5

Cite this article as:
Klein, R., Blaschke, S., Neumaier, B. et al. Stem Cell Rev and Rep (2014) 10: 539. doi:10.1007/s12015-014-9512-5

Abstract

The neural cell adhesion molecule (NCAM) plays a role in neurite outgrowth, synaptogenesis, and neuronal differentiation. The NCAM mimetic peptide FG Loop (FGL) promotes neuronal survival in vitro and enhances spatial learning and memory in rats. We here investigated the effects of FGL on neural stem cells (NSC) in vitro and in vivo. In vitro, cell proliferation of primary NSC was assessed after exposure to various concentrations of NCAM or FGL. The differentiation potential of NCAM- or FGL-treated cells was assessed immunocytochemically. To investigate its influence on endogenous NSC in vivo, FGL was injected subcutaneously into adult rats. The effects on NSC mobilization were studied both via non-invasive positron emission tomography (PET) imaging using the tracer [18F]-fluoro-l-thymidine ([18F]FLT), as well as with immunohistochemistry. Only FGL significantly enhanced NSC proliferation in vitro, with a maximal effect at 10 μg/ml. During differentiation, NCAM promoted neurogenesis, while FGL induced an oligodendroglial phenotype; astrocytic differentiation was neither affected by NCAM or FGL. Those differential effects of NCAM and FGL on differentiation were mediated through different receptors. After FGL-injection in vivo, proliferative activity of NSC in the subventricular zone (SVZ) was increased (compared to placebo-treated animals). Moreover, non-invasive imaging of cell proliferation using [18F]FLT-PET supported an FGL-induced mobilization of NSC from both the SVZ and the hippocampus. We conclude that FGL robustly induces NSC mobilization in vitro and in vivo, and supports oligodendroglial differentiation. This capacity renders FGL a promising agent to facilitate remyelinization, which may eventually make FGL a drug candidate for demyelinating neurological disorders.

Keywords

NCAMNCAM-derived peptide FG LoopPrimary neural stem cellsRemyelination[18F]FLTPositron-Emission-Tomography

Copyright information

© Springer Science+Business Media New York 2014

Authors and Affiliations

  • Rebecca Klein
    • 1
    • 2
  • Stefan Blaschke
    • 1
  • Bernd Neumaier
    • 2
  • Heike Endepols
    • 2
  • Rudolf Graf
    • 2
  • Meike Keuters
    • 1
  • Joerg Hucklenbroich
    • 1
  • Morten Albrechtsen
    • 4
  • Stephen Rees
    • 4
  • Gereon Rudolf Fink
    • 1
    • 3
  • Michael Schroeter
    • 1
    • 3
  • Maria Adele Rueger
    • 1
    • 3
  1. 1.Department of NeurologyUniversity Hospital of CologneCologneGermany
  2. 2.Max Planck Institute for Neurological ResearchCologneGermany
  3. 3.Cognitive Neurology Section, Institute of Neuroscience and Medicine Research Centre JuelichJuelichGermany
  4. 4.Enkam Pharmaceuticals A/SCopenhagenDenmark