Hippocampal adult neurogenesis is enhanced by chronic eszopiclone treatment in rats

J Sleep Res. 2010 Sep;19(3):384-93. doi: 10.1111/j.1365-2869.2010.00833.x. Epub 2010 Apr 7.

Abstract

The adult hippocampal dentate gyrus (DG) exhibits cell proliferation and neurogenesis throughout life. We examined the effects of daily administration of eszopiclone (Esz), a commonly used hypnotic drug and gamma-aminobutyric acid (GABA) agonist, compared with vehicle, on DG cell proliferation and neurogenesis, and on sleep-wake patterns. Esz was administered during the usual sleep period of rats, to mimic typical use in humans. Esz treatment for 7 days did not affect the rate of cell proliferation, as measured by 5-bromo-2'-deoxyuridine (BrdU) immunostaining. However, twice-daily Esz administration for 2 weeks increased survival of newborn cells by 46%. Most surviving cells exhibited a neuronal phenotype, identified as BrdU-neuronal nuclei (NeuN) double-labeling. NeuN is a marker of neurons. Non-rapid eye movement sleep was increased on day 1, but not on days 7 or 14 of Esz administration. Delta electroencephalogram activity was increased on days 1 and 7 of treatment, but not on day 14. There is evidence that enhancement of DG neurogenesis is a critical component of the effects of antidepressant treatments of major depressive disorder (MDD). Adult-born DG cells are responsive to GABAergic stimulation, which promotes cell maturation. The present study suggests that Esz, presumably acting as a GABA agonist, has pro-neurogenic effects in the adult DG. This result is consistent with evidence that Esz enhances the antidepressant treatment response of patients with MDD with insomnia.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Azabicyclo Compounds / administration & dosage
  • Azabicyclo Compounds / pharmacology*
  • Cell Count
  • Cell Survival / drug effects
  • Eszopiclone
  • Hippocampus / cytology
  • Hippocampus / drug effects*
  • Hippocampus / growth & development
  • Hypnotics and Sedatives / administration & dosage
  • Hypnotics and Sedatives / pharmacology*
  • Male
  • Neurogenesis / drug effects*
  • Piperazines / administration & dosage
  • Piperazines / pharmacology*
  • Rats
  • Rats, Sprague-Dawley
  • Sleep / drug effects
  • Time Factors

Substances

  • Azabicyclo Compounds
  • Hypnotics and Sedatives
  • Piperazines
  • Eszopiclone