Discipline: Biological Sciences
Subcategory: Physiology and Health
Session: 4
Room: Exhibit Hall
Kayleigh M. Paddock - University of Arizona
Co-Author(s): Erin K. Conant, University of Arizona, Tucson, AZ; Farah S. Sawal, University of Arizona, Tucson, AZ; David Sands, Montana State University, Bozeman, MT; Edward Dratz, Montana State University, Bozeman, MT; Steve D. Coon, Fort Peck Community College, Poplar, MT; Jennifer A. Teske, University of Arizona, Tucson, AZ
Dietary strategies are needed to mitigate the high prevalence of type II diabetes and obesity. Acute consumption of foods with a low glycemic index (LGI) lead to a lower rise in postprandial blood glucose compared to foods with a high glycemic index (HGI), which would be beneficial for individuals with type II diabetes. The effect of LGI foods on weight gain have been mixed. The purpose of this study was to test the hypothesis that chronic consumption of a diet with a LGI low food (i.e. potato) would lead to favorable blood glucose levels and less weight gain in a rodent model of obesity regardless of sex or the background diet. Methods: Commercially available Russet (HGI) and Huckleberry gold (LGI) potatoes were boiled, freeze-dried and then incorporated into a 10% low fat (LF) and 45% high fat (HF) diet (Research Diets), which produced 4 diets (LGI-LF, LGI-HF, HGI-LF, HGI-HF) that had equal amounts of protein and carbohydrate. The macronutrient profile of the freeze-dried powders were verified (Medallion Laboratories) prior to incorporation into the LF and HF diet. Sprague-Dawley rats (n=20/sex per diet) were randomized and fed the LF or HF diet for 2 weeks to acclimate the rats to the diets. Then rats were randomized (within each sex and diet) to either a diet containing the HGI (i.e. control) or LGI potato. Rats (n=10/group) were fed these diets for 2 weeks. Weight gain and food intake were determined every 48h throughout the study. Body composition (EchoMRI) was determined at baseline and on days 14, and 28 of the study. Blood glucose was determined at euthanasia with a glucometer. Results/Discussion: Rats fed the LGI potato had significantly lower blood glucose compared to those fed the HGI potato independent of sex or the background diet (LF or HF). The HF diet significantly increased weight gain after 2 weeks in males only. GI and the background diet (LF or HF) had no effect on weight gain at the end of the study despite the males gaining significantly more weight compared to females. Conclusion: Chronic consumption of a diet supplemented with a LGI potato may be beneficial for individuals with type II diabetes regardless of the percentage of fat in the background diet. Future questions: Did the LGI potato augment glucose transporters in the small intestine? Can these results be replicated in individuals with pre-diabetes and type II diabetes?
Funder Acknowledgement(s): Funding for this research was supported by the Western Alliance to Expand StudentOpportunities (S2021ur0014, F2021ur0006), the National Institutes of Health ofEnvironmental Health Sciences (Grant #2-R25-ES025494) and the U.S. Departmentof Agriculture (ARZT-1372540-R23-131).
Faculty Advisor: Jennifer Teske, teskeja@arizona.edu
Role: The portion I was responsible for included animal facility work, collecting data, and analyzing results via ANOVA and t-tests. Over the span of the study, I measured food intake, body weight, and body composition using EchoMRI.