Impaired adult hippocampal neurogenesis and its partial reversal by chronic treatment of fluoxetine in a mouse model of Angelman syndrome

Biochem Biophys Res Commun. 2015 Sep 4;464(4):1196-1201. doi: 10.1016/j.bbrc.2015.07.103. Epub 2015 Jul 29.

Abstract

Angelman syndrome (AS) is a neurodevelopmental disorder characterized by severe cognitive and motor deficits, caused by the loss of function of maternally inherited Ube3a. Ube3a-maternal deficient mice (AS model mice) recapitulate many essential features of AS, but how the deficiency of Ube3a lead to such behavioural abnormalities is poorly understood. Here we have demonstrated significant impairment of adult hippocampal neurogenesis in AS mice brain. Although, the number of BrdU and Ki67-positive cell in the hippocampal DG region was nearly equal at early postnatal days among wild type and AS mice, they were significantly reduced in adult AS mice compared to wild type controls. Reduced number of doublecortin-positive immature neurons in this region of AS mice further indicated impaired neurogenesis. Unaltered BrdU and Ki67-positive cells number in the sub ventricular zone of adult AS mice brain along with the absence of imprinted expression of Ube3a in the neural progenitor cell suggesting that Ube3a may not be directly linked with altered neurogenesis. Finally, we show that the impaired hippocampal neurogenesis in these mice can be partially rescued by the chronic treatment of antidepressant fluoxetine. These results suggest that the chronic stress may lead to reduced hippocampal neurogenesis in AS mice and that impaired neurogenesis could contribute to cognitive disturbances observed in these mice.

Keywords: Angelman syndrome; Fluoxetine; Hippocampus; Neurogenesis; Stress.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult Stem Cells / drug effects
  • Adult Stem Cells / pathology*
  • Angelman Syndrome / drug therapy*
  • Angelman Syndrome / pathology*
  • Angelman Syndrome / physiopathology
  • Animals
  • Antidepressive Agents / administration & dosage
  • Cell Differentiation / drug effects
  • Cell Proliferation / drug effects
  • Chronic Disease
  • Fluoxetine / administration & dosage*
  • Hippocampus
  • Mice
  • Neurogenesis / drug effects*
  • Neurons / drug effects
  • Neurons / pathology*
  • Treatment Outcome

Substances

  • Antidepressive Agents
  • Fluoxetine