Date of Award
2019
Document Type
Thesis
Degree Name
Bachelors
Department
Natural Sciences
First Advisor
Walstrom, Katherine
Area of Concentration
Biochemistry
Abstract
In the midst of the obesity epidemic, a broad understanding of metabolic conditions is necessary for proper care of obese and overweight individuals. Rebound weight gain, that which follows a period of significant weight loss, is an adaptive symptom which minimizes the utility of caloric deficit as a long-term treatment of obesity. Rebound weight gain is documented in humans and mice, and mice have been found with increased levels of a fat-synthesis gene, acetyl CoA carboxylase (ACC, pod- 2), in response to starvation and refeeding. In the present study, the model organism, Caenorhabditis elegans, was age-matched with hypochlorite treatment, starved in the L2 life stage, and refed from the mid L3 to young adult life stages. The stain analysis showed that the experimental worms had an increase in total fat mass, but they also showed an increase in age. With RT-PCR, 5 fat-related genes—hosl-1, cpt-2, pod-2, mboa-2, and sbp-1—were evaluated for expression-level changes. Sbp-1 showed an increase while cpt-2 showed a decrease; these changes are consistent with an increase in fat accumulation efficiency. However, hosl-1 expression was increased as was the mean age of the experimental worms, suggesting that age-related changes might have confounded the effects of starvation. Pod-2 showed no changes in expression, which was inconsistent with previous murine studies; possibly this also suggests that age-related changes caused the results shown here. The function of mboa-2 is not fully known and this study suggests that is it unrelated to starvation or rebound weight gain. Future work should increase the breadth of this analysis, including testing of other genes related to fat metabolic pathways and adding a western blot for protein quantification, in order to determine if several possible hypothesis explain the results listed herein.
Recommended Citation
Nosacka, Sarah, "Exploration of molecular basis for rebound weight gain in Caenorhabditis elegans." (2019). Theses & ETDs. 5766.
https://digitalcommons.ncf.edu/theses_etds/5766