Title:Is Adult Hippocampal Neurogenesis Really Relevant for the Treatment of Psychiatric Disorders?
Volume: 19
Issue: 10
Author(s): Marco Carli, Stefano Aringhieri, Shivakumar Kolachalam, Biancamaria Longoni, Giovanna Grenno, Mario Rossi, Angelo Gemignani, Francesco Fornai, Roberto Maggio and Marco Scarselli*
Affiliation:
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Pisa,Italy
Keywords:
Adult hippocampal neurogenesis, antidepressants, mood stabilizers, atypical antipsychotics, receptor biased agonism,
physical activity, restorative sleep.
Abstract:
Adult neurogenesis consists in the generation of newborn neurons from neural stem
cells taking place in the adult brain. In mammals, this process is limited to very few areas of the
brain, and one of these neurogenic niches is the subgranular layer of the dentate gyrus (DG) of the
hippocampus. Adult newborn neurons are generated from quiescent neural progenitors (QNPs),
which differentiate through different steps into mature granule cells (GCs), to be finally integrated
into the existing hippocampal circuitry.
In animal models, adult hippocampal neurogenesis (AHN) is relevant for pattern discrimination,
cognitive flexibility, emotional processing and resilience to stressful situations. Imaging techniques
allow to visualize newborn neurons within the hippocampus through all their stages of development
and differentiation. In humans, the evidence of AHN is more challenging, and, based on recent
findings, it persists through adulthood, even if it declines with age. Whether this process has
an important role in human brain function and how it integrates into the existing hippocampal circuitry
is still a matter of exciting debate. Importantly, AHN deficiency has been proposed to be relevant
in many psychiatric disorders, including mood disorders, anxiety, post-traumatic stress disorder
and schizophrenia.
This review aims to investigate how AHN is altered in different psychiatric conditions and how
pharmacological treatments can rescue this process. In fact, many psychoactive drugs, such as antidepressants,
mood stabilizers and atypical antipsychotics (AAPs), can boost AHN with different
results. In addition, some non-pharmacological approaches are discussed, as well.