The Effect of Strain and Exercise on Hypothalmic Gene Expression in C57BL/6J and DBA/2J Mice
Open Access
- Author:
- Metkus, James Scott
- Area of Honors:
- Kinesiology
- Degree:
- Bachelor of Science
- Document Type:
- Thesis
- Thesis Supervisors:
- Teresa Caroldean Lang, Thesis Supervisor
Jinger S. Gottschall, Thesis Honors Advisor - Keywords:
- Skeletal Quality
B6 mice
D2 mice
Hypothalamus
Exercise - Abstract:
- Osteoporosis is a degenerative bone disease that affects a majority of Americans, specifically those of older age. Within the last few decades, researchers have begun to consider neurological pathways that contribute to osteoporosis and other bone disorders, including hormonal effects on osteoporosis or other bone disorders. There have been decades of studies focusing on exercise and it has been shown that exercise has positive effects on bone mass by increasing bone density and gene expression within bone. However, there is a lack of research on how exercise affects gene expression within the brain or specific parts of the brain, such as the hypothalamus. In this study, 77 480 day old C57BL/6 (B6) and DBA/2J(D2) female mice were divided into three treatment groups: a treadmill running group (14 B6 and 14 D2 mice), a tower climbing group (13 B6 and 12 D2) and finally a sedentary control group (14 B6 and 10 D2). After 5 weeks of exercise treatment, RNA was extracted from the hypothalamus of each mouse, homogenized and underwent Nanodrop and Bioanalyzer assessment for quality control. Two samples were pooled onto three gene chips for each treatment group in order to measure gene expression within the hypothalamus. Gene expression was then compared across to identify differential gene expression as a function of mouse strain and/or exercise. While the exercise treatment did not produce significant differences in gene expression, important differences that were suggested from this study include the expression of Insulin Growth factor-1(IGF-1) in B6 tower climbing as compared to B6 sedentary controls. In terms of strain differences, around 497 genes were differentially expressed between B6 and D2 mice. The identification of genes such as IGF-1 within the hypothalamuses of B6 and D2 mice may help provide greater insight into how differences in activity levels and genetics may lead to the elucidation of new pathways for the prevention as well as treatment of osteoporosis and other bone disorders.