Galanin promotes neuronal differentiation in murine subventricular zone cell cultures

Stem Cells Dev. 2013 Jun 1;22(11):1693-708. doi: 10.1089/scd.2012.0161. Epub 2013 Mar 1.

Abstract

Neural stem cells of the subventricular zone (SVZ) represent a potentially important source of surrogate cells for the treatment of brain damage. Proper use of these cells for neuronal replacement depends on the ability to drive neuronal differentiation. Several neuromodulators stimulate neurogenesis. Here we examined the effects of the neuropeptide galanin, on neuronal differentiation in murine SVZ cultures. SVZ neurospheres obtained from early postnatal mice were treated with 10 nM to 2 μM galanin. Galanin promoted neuronal differentiation, increasing numbers of NeuN-, vesicular GABA transporter- and tyrosine hydroxylase-expressing neurons. In contrast, galanin neither affected cell proliferation assessed by BrdU incorporation nor cell death evaluated by terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL). Neuronal differentiation was further confirmed at the functional level by measuring [Ca(2+)]i variations in single SVZ cells after KCl and histamine stimulations to distinguish neurons from immature cells. Galanin treatment increased the numbers of neuronal-like responding cells compared to immature cells. Using selective agonists (M617, AR-M1896) and antagonists (galantide, M871) for galanin receptors 1 and 2, we showed that both galanin receptors mediated neuronal differentiation. Early proneuronal effects of galanin included positive regulation of the transcription factor neurogenin-1 (Ngn1). In addition, galanin promoted axonogenesis and dendritogenesis, increasing both the length of phosphorylated stress-activated protein kinase- and Tau-positive axons and the numbers of microtubule associated protein-2 (MAP-2)-labelled dendrites. Moreover, galanin inhibited SVZ cell migration in the transwell assay. Our results show a proneurogenic effect of galanin and open new perspectives for future applications in stem cell-based therapies for neuronal replacement.

MeSH terms

  • Animals
  • Basic Helix-Loop-Helix Transcription Factors / metabolism
  • Cell Culture Techniques
  • Cell Death / drug effects
  • Cell Differentiation / drug effects*
  • Cell Movement
  • Cell Proliferation / drug effects
  • Cells, Cultured
  • Cerebral Ventricles / cytology
  • Cerebral Ventricles / drug effects
  • DNA-Binding Proteins
  • Galanin / metabolism
  • Galanin / pharmacology*
  • Mice
  • Mice, Inbred C57BL
  • Microtubule-Associated Proteins / metabolism
  • Nerve Tissue Proteins / biosynthesis
  • Nerve Tissue Proteins / metabolism
  • Neural Stem Cells / metabolism*
  • Neurogenesis / physiology
  • Neurons / metabolism
  • Nuclear Proteins / biosynthesis
  • Peptide Fragments / pharmacology
  • Receptor, Galanin, Type 1 / metabolism*
  • Receptor, Galanin, Type 2 / metabolism*
  • Tyrosine 3-Monooxygenase / biosynthesis
  • Vesicular Inhibitory Amino Acid Transport Proteins / biosynthesis

Substances

  • Basic Helix-Loop-Helix Transcription Factors
  • DNA-Binding Proteins
  • Microtubule-Associated Proteins
  • Mtap2 protein, mouse
  • Nerve Tissue Proteins
  • NeuN protein, mouse
  • Nuclear Proteins
  • Peptide Fragments
  • Receptor, Galanin, Type 1
  • Receptor, Galanin, Type 2
  • Vesicular Inhibitory Amino Acid Transport Proteins
  • galanin (2-11)-amide
  • vesicular GABA transporter
  • Neurog1 protein, mouse
  • Galanin
  • Tyrosine 3-Monooxygenase