Exploring the Effects of Adolescent Exposure to Social Instability Stress on Anxiety and Risk-Assessment Behavior in Male C57BL/6J and C57BL/6NJ Mice

open_access
Open Access
Author:
Gerboc, Lia
Area of Honors:
Biology
Degree:
Bachelor of Science
Document Type:
Thesis
Thesis Supervisors:
Thomas J Gould, Thesis Supervisor
C. Guilherme Becker, Thesis Honors Advisor
Keywords:
adolescence
social instability stress
anxiety
risk assessment
EPM
stress susceptibility
male mice
Abstract:
Adolescence is a critical period for emotional and cognitive development, during which stress can have lasting effects on behavior and mental health, including the development of anxiety. Social instability stress (SIS), a model of chronic early-life stress, mimics social challenges often faced by adolescents in human populations and induces psychological stress in rodents. Risk-assessment behavior, involving cautious exploration and threat evaluation, is crucial for survival and plays a significant role in human maturation. Risk assessment and anxiety are closely intertwined, as heightened anxiety can lead to risk aversion and/or changes in risk-assessment behavior. Understanding how SIS impacts anxiety-like and risk-assessment behaviors during adolescence is essential, as the behaviors are closely linked to long-term mental health outcomes, including anxiety disorders and how adolescents respond to stress. This honors thesis investigated the effects of SIS on anxiety-like and risk-assessment behaviors in male adolescent C57BL/6J and C57BL/6NJ mice, also exploring the genetic influences on stress susceptibility during adolescence. It was hypothesized that SIS would increase anxiety-like and risk-assessment behavior. Mice were randomly assigned to a SIS or control condition and tested on the elevated plus maze (EPM). Results showed that SIS increased anxiety-like behavior and affected risk-assessment behavior in the EPM, emphasizing the impact of adverse social experiences on health throughout development. A strain-stress interaction for stretch attend posture (SAP) frequency suggests genetic differences in stress regulation and response, which could explain why individuals differ in stress susceptibility. These findings indicate the potential for future research and have important implications for how stress is regulated and how the onset of stress impacts risk-assessment behavior.