Ectopic expression of doublecortin protects adult rat progenitor cells and human glioma cells from severe oxygen and glucose deprivation

Neuroscience. 2006 Oct 27;142(3):739-52. doi: 10.1016/j.neuroscience.2006.06.065. Epub 2006 Sep 8.

Abstract

Doublecortin (DCX) is a microtubule-associated protein expressed in migrating neuroblasts. DCX expression is increased in subventricular zone (SVZ) cells migrating to the boundary of an ischemic lesion after induction of middle cerebral artery occlusion (MCAO) in adult rats and mice. We tested the hypothesis that DCX, in addition to being a marker of migrating neuroblasts, serves to protect neuroblasts from conditions of stress, such as oxygen and glucose deprivation (OGD). Using gene transfer technology, we overexpressed DCX in rat SVZ and U-87 human glioma cells. The cells remained viable against severe OGD, up to 32 h exhibiting 1% apoptosis compared with 100% apoptosis in control. In addition, these genetically modified cells upregulated expression of E-, VE- and N-cadherin, molecules that promote endothelial survival signals via the VE-cadherin/vascular endothelial growth factor receptor-2/phosphoinositide 3-kinase (PI3-K)/AKT/beta-catenin pathway and inactivate the proapoptotic factor Bad. DCX overexpression also significantly increased cell migration in SVZ tissue explants and U-87 cells and significantly upregulated microtubule-associated protein-2 (MAP2) and nestin protein levels in SVZ and U-87 cells compared with wild-type control cells. Knocking down DCX expression in DCX overexpressing SVZ and U-87 cells with DCX small interfering RNA (siRNA), confirmed the specificity of DCX on cell survival against OGD, and the DCX induced upregulation of E-, VE- and N-cadherin, MAP2 and nestin. In NIH3T3 cells, DCX overexpression had no effect on cell survival against OGD, and indicating that the protective effects of DCX was restricted to brain cells e.g. SVZ and U-87 cells. Our data suggest a novel and an important role for DCX as a protective agent for migrating neuroblasts and tumor cells.

Publication types

  • Comparative Study
  • Research Support, N.I.H., Extramural

MeSH terms

  • Analysis of Variance
  • Animals
  • Apoptosis / drug effects
  • Apoptosis / physiology
  • Brain / cytology
  • Cadherins / classification
  • Cadherins / metabolism
  • Cell Movement / drug effects
  • Cell Movement / physiology
  • Cells, Cultured
  • Doublecortin Domain Proteins
  • Doublecortin Protein
  • Gene Expression Regulation / physiology*
  • Glioma / metabolism*
  • Glucose / deficiency*
  • Humans
  • Hypoxia / metabolism*
  • In Situ Nick-End Labeling / methods
  • Intermediate Filament Proteins / metabolism
  • Male
  • Mice
  • Microtubule-Associated Proteins / genetics
  • Microtubule-Associated Proteins / metabolism
  • Microtubule-Associated Proteins / physiology*
  • Nerve Tissue Proteins / metabolism
  • Nestin
  • Neuropeptides / genetics
  • Neuropeptides / physiology*
  • RNA, Small Interfering / pharmacology
  • Rats
  • Rats, Wistar
  • Stem Cells / metabolism*
  • Time Factors
  • Transfection / methods
  • beta-Galactosidase / metabolism

Substances

  • Cadherins
  • DCX protein, human
  • Dcx protein, mouse
  • Dcx protein, rat
  • Doublecortin Domain Proteins
  • Doublecortin Protein
  • Intermediate Filament Proteins
  • MAP2 protein, human
  • Microtubule-Associated Proteins
  • NES protein, human
  • Nerve Tissue Proteins
  • Nes protein, mouse
  • Nes protein, rat
  • Nestin
  • Neuropeptides
  • RNA, Small Interfering
  • beta-Galactosidase
  • Glucose