By Nathan Terrell

Faculty Mentor: Dr. Waters

Abstract

Exercise is known to increase memory and elevate mood in both mice and humans. Two important molecules are Brain derived neurotrophic factor (BDNF) and Corticotropin-releasing hormone (CRH). The prefrontal cortex plays a role in controlling stress. The hypothalamus is the main mediator of CRH in the brain. Regular exercise is an important factor in brain function and mental health. Finding out which molecules are highly expressed in each region of the brain would allow for a better understanding of the mechanisms behind the mental benefits of exercise. It was hypothesized that BDNF levels in the prefrontal cortex would be elevated and that CRH levels in the hypothalamus would be decreased in the exercised mice in comparison to the sedentary mice.
Twenty mice were split into two groups: one with access to a running wheel, and one without access to a running wheel. For six weeks, the mice lived in groups of five in a cage. They were then killed and their brains were collected. PCR analysis was then used to quantify the amount of BDNF and CRH in each brain region.
BDNF levels in the prefrontal cortex were higher in the mice that exercised when compared to the mice that were sedentary. CRH levels in the hypothalamus were lower in the mice that exercised when compared to the mice that were sedentary.
Exercise plays an essential role in preventing neurodegeneration and maintaining good brain function. It is also important in decreasing stress and anxiety.