Stress and hippocampal neurogenesis

Area of Science:

• Neuroscience
• Developmental Biology
• Cell Biology

Background:

• The dentate gyrus (DG) exhibits prolonged development from gestation through adulthood.
• Adult neurogenesis in the DG is conserved across mammalian species.
• This extended development renders the DG susceptible to environmental influences.

Purpose of the Study:

• To review the unique developmental trajectory of the dentate gyrus.
• To explore the impact of environmental factors, particularly stress, on DG development and function.
• To discuss the long-term consequences of early life events on hippocampal function.

Main Methods:

• Review of existing literature on dentate gyrus development and adult neurogenesis.
• Analysis of studies investigating the role of adrenal steroids and stress on granule cell precursor proliferation.
• Examination of the mechanisms underlying stress-induced inhibition of neurogenesis.

Main Results:

• Granule cell production in the DG is modulated by circulating adrenal steroids.
• Glucocorticoids inhibit proliferation via an NMDA receptor-dependent pathway.
• Stressful experiences elevate glucocorticoids, inhibit precursor proliferation, and alter DG structure.

Conclusions:

• The dentate gyrus's protracted development makes it vulnerable to environmental perturbations.
• Chronic stress leads to sustained inhibition of neurogenesis and structural changes in the DG.
• Stress-induced alterations in DG neurogenesis may be a mechanism by which stress impacts hippocampal function.