By Sabrina Perez, Kori Wilson, Paola Marquez

Faculty Mentor: Dr. Parrish Waters

Abstract

Anxiety disorders affect over 40 million adults in the US. Regular physical activity reduces anxiety, elevates mood, and improves stress resilience, but the underlying biological mechanisms are not fully understood. Brain-derived neurotrophic factor (BDNF) is a protein that elicits neuron growth and synapse formation, and BDNF expression in the amygdala is associated with elevated levels of anxiety in mice. To explore the relationship between exercise and anxiety, we kept colonies of female mice with either no access, limited access, or unlimited access to voluntary running wheels. We chose female mice due to the higher prevalence of anxiety disorders in women. We used the Elevated Plus Maze to assess anxiety-related behavior and performed an ELISA to quantify levels of BDNF in the amygdala. Our results indicate that unlimited exercise reduces one measure of anxiety, and limited access increases other measures of anxiety, perhaps due to the stress of competition for the wheel. Exercise did not affect BDNF in the amygdala, suggesting that the behavioral effects that we observe may be due to changes in other physiological systems, which should be investigated in future studies.