Alterations in circadian entrainment precede the onset of depression-like behavior that does not respond to fluoxetine.

ABSTRACT: Growing evidence links adverse prenatal conditions to mood disorders. We investigated the long-term behavioral alterations induced by prenatal exposure to excess glucocorticoids (dexamethasone--DEX). At 12 months, but not earlier, DEX-exposed mice displayed depression-like behavior and impaired hippocampal neurogenesis, not reversible by the antidepressant fluoxetine (FLX). Concomitantly, we observed arrhythmic glucocorticoid secretion and absent circadian oscillations in hippocampal clock gene expression. Analysis of spontaneous activity showed progressive alterations in circadian entrainment preceding depression. Circadian oscillations in clock gene expression (measured by means of quantitative PCR) were also attenuated in skin fibroblasts before the appearance of depression. Interesting

SUBMITTER: Spulber S 

PROVIDER: S-EPMC5068723 | biostudies-literature | 2015 Jul

REPOSITORIES: biostudies-literature