Abstract

Stressful events during adulthood are potent adverse environmental factors that can predispose individuals to psychiatric disorders, including depression; however, many individuals exposed to stressful events can adapt and function normally. While stress vulnerability may influence depression, the molecular mechanisms underlying the susceptibility and adaptation to chronic stress within the brain are poorly understood. In this study, two genetically distinct mouse strains that exhibit different behavioral responses to chronic stress were used to demonstrate how the differential epigenetic status of the glial cell-derived neurotrophic factor (Gdnf) gene in the ventral striatum modulates susceptibility and adaptation to chronic stress. Our results suggest that the histone modifications and DNA methylation of the Gdnf promoter have crucial roles in the control of behavioral responses to chronic stress. Our data provide insights into these mechanisms, suggesting that epigenetic modifications of Gdnf, along with genetic and environmental factors, contribute to behavioral responses to stress.