Date of Defense


Date of Graduation



Biological Sciences

First Advisor

John Spitsbergen

Second Advisor

David Huffman

Third Advisor

Alberto Felipe


Exercise is a positive form of reinforcing positive lifestyle choices. There are many benefits to exercising such as decreased risk of cardiovascular disease and improved mental condition (Centers for Disease Control and Prevention). In addition, exercise can serve a protecting role for the nervous system. One form in which exercise can protect the nervous system is by increasing the production of neurotrophic factors, specifically glial cell line-derived neurotrophic factor. Another way by which exercise can protect the nervous system is by preserving muscle tissue due to actively recruiting it. The goal of this study was to explore the effects of aging and exercise on extensor digitorum longus (EDL) from 4-week-old and 1-year-old rats. EDL is primarily a fast-twitch fiber (Staron et al., 1999). Enzyme-linked immunosorbent assay (ELISA) and Western Blot were used to compare GDNF protein content and phenotype switch between fast and slow-twitch muscle fibers between sedentary and exercised subjects. An increase in GDNF occurred from the young rats to 1-year-old sedentary rats. No significant differences in GDNF content were noted between sedentary and exercised 1-year-old rats. Fast-twitch muscle fiber was detected in all three groups of rats. Understanding molecular mechanisms can lead to insight on the protection of nervous system due to exercise.

Access Setting

Honors Thesis-Open Access