Researchers identify brain pathway impairing postpartum social behavior following adolescent stress

In a Nature Communications study, the University of Alabama at Birmingham researchers used a mouse model and cutting-edge neurobiological techniques to show how psychological stress during adolescence alters neuronal functions in the brain, resulting in altered postpartum social behavior.

This research builds on their recent finding that mice exposed to social isolation in late adolescence, which alone causes no endocrine or behavioral changes, show long-lasting behavioral changes only when accompanied by pregnancy and delivery. They were able to use this behavioral model to probe for postpartum neural circuit differences between mouse dams that were stressed in late adolescence and a control group of mouse dams that remained unstressed in adolescence, due to normal social interactions with other mice.

The UAB researchers used optogenetics — where light signals can selectively activate or inhibit brain circuits — and in vivo calcium imaging, which allows researchers to examine the neuronal activity of specific neurons in a brain region. These approaches allow investigators to understand how nerve cells communicate in freely-behaving animals.

The UAB Department of Psychiatry and Behavioral Neurobiology researchers found that adolescent psychosocial stress, combined with pregnancy and delivery, caused hypofunction of the glutamatergic pathway that they mapped from the anterior insula region of the brain cortex to the prelimbic cortex. Glutamate is the main excitatory neurotransmitter in the central nervous systems of mammals.

Reference: Adolescent stress impairs postpartum social behavior via an anterior insula-prelimbic pathway in mice, Nature Communications, DOI 10.1038/s41467-023-38799-6