Fibulin-2 is a key mediator of the pro-neurogenic effect of TGF-beta1 on adult neural stem cells

Mol Cell Neurosci. 2015 Jul:67:75-83. doi: 10.1016/j.mcn.2015.06.004. Epub 2015 Jun 5.

Abstract

Transforming growth factor beta 1 (TGF-beta1), an anti-inflammatory cytokine, has been shown to have pro-neurogenic effects on adult Neural Stem Cells (aNSC) from the dentate gyrus and in vivo models. Here, we expanded the observation of the pro-neurogenic effect of TGF-beta1 on aNSC from the subventricular zone (SVZ) of adult rats and performed a functional genomic analysis to identify candidate genes to mediate its effect. 10 candidate genes were identified by microarray analysis and further validated by qRT-PCR. Of these, Fibulin-2 was increased 477-fold and its inhibition by siRNA blocks TGF-beta1 pro-neurogenic effect. Curiously, Fibulin-2 was not expressed by aNSC but by a GFAP-positive population in the culture, suggesting an indirect mechanism of action. TGF-beta1 also induced Fibulin-2 in the SVZ in vivo. Interestingly, 5 out of the 10 candidate genes identified are known to interact with integrins, paving the way for exploring their functional role in adult neurogenesis. In conclusion, we have identified 10 genes with putative pro-neurogenic effects, 5 of them related to integrins and provided proof that Fibulin-2 is a major mediator of the pro-neurogenic effects of TGF-beta1. These data should contribute to further exploring the molecular mechanism of adult neurogenesis of the genes identified and the involvement of the integrin pathway on adult neurogenesis.

Keywords: Adult neural stem cells; Adult neurogenesis; Fibulin-2; Genomics; Subventricular zone; Transforming growth factor-beta 1.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult Stem Cells / cytology
  • Adult Stem Cells / drug effects
  • Adult Stem Cells / metabolism*
  • Animals
  • Astrocytes / metabolism
  • Calcium-Binding Proteins / genetics
  • Calcium-Binding Proteins / metabolism*
  • Cells, Cultured
  • Extracellular Matrix Proteins / genetics
  • Extracellular Matrix Proteins / metabolism*
  • Integrins / metabolism
  • Lateral Ventricles / cytology
  • Lateral Ventricles / growth & development
  • Lateral Ventricles / metabolism
  • Neural Stem Cells / cytology
  • Neural Stem Cells / drug effects
  • Neural Stem Cells / metabolism*
  • Neurogenesis*
  • Rats
  • Rats, Wistar
  • Transforming Growth Factor beta1 / metabolism
  • Transforming Growth Factor beta1 / pharmacology*

Substances

  • Calcium-Binding Proteins
  • Extracellular Matrix Proteins
  • Integrins
  • Transforming Growth Factor beta1
  • fibulin 2