Location: Diet, Genomics and Immunology Laboratory
2024 Annual Report
Objectives
1: Develop a refined New Total Western Diet for rodent studies and determine the effect of diet composition on gut microbiota composition, function, and experimental colitis. [NP107, C3, PS3B]
2: Determine the effect of different types and sources of resistant starches added to the modified New Total Western Diet on gut microbiota composition, function, and experimental colitis. [NP107, C3, PS3A, PS3B]
3: Determine the effect of different foods (cooked beans or fruits and vegetables) added to a Western style diet on gut microbiota composition, gastrointestinal function, and experimental colitis. [NP107, C3, PS3A, PS3B; C4, PS4A]
Subobjective 3A - Determine the impact of cooked beans on gut microbiome composition, function, and response to experimental colitis models in mice and swine.
Subobjective 3B: Determine the impact of fruit and/or vegetable supplemented diets at DGA recommended levels on gut microbiome composition and function in WD-Ossabaw pig model.
Subobjective 3C. Determine the effect of fruit and vegetable dietary supplementation on host inflammatory response against Dextran Sodium Sulfate (DSS) induced colitis in a WD Ossabaw pig model.
Approach
The studies proposed in the current project plan will use a complementary approach to take advantage of the strengths of each model system. Mice will be used as a lower-cost, high-throughput screening tool to evaluate the effect of RS and beans on the microbiome, metabolome, gene expression, and resistance to colitis. The proposed mouse models in this project plan will provide flexibility to evaluate several classes of dietary RS and beans at various concentrations and combinations to evaluate mucosal responses to both DSS- and bacterial- induced colitis. The results from these studies will be evaluated, and the most promising candidate foods will then be used to test mechanism-based effects in a pig model that is likely to yield data highly relevant to humans. Preliminary studies from our laboratory indicate that consumption of FVs improves the outcome of DSS-induced colitis in pigs, and this line of research will be explored further. The effects of RS, FVs, and beans on the pig microbiome, metabolome and glycome will be evaluated and correlated with changes to mucosal immunity. Data derived from this proposal will identify and characterize the host response after consumption of experimental diets targeted to be protective against inflammatory conditions. Results from the pig studies will inform recommendations for dietary RS, FV, and beans predictive of improved intestinal health in humans and can identify points of inquiry suitable for human trials.
Progress Report
Most nutritional studies use diets that do not reflect what is consumed by a typical American. We have been using a Total Western Diet (TWD) whose macro- and micronutrient composition is based on 50 percentile intake from NHANES data to better reflect what an average American consumes. However, the TWD only has one source of protein, casein, and one source of fiber, cellulose. To address this shortcoming, we are developing modified versions of the TWD that have multiple sources of protein and fiber. We are working with Dr. Korry Hintze at Utah State University and Nicole Tiry, a nutritionist with Inotivico on formulating TWDs to include sources of protein (casein, whey, chicken, beef, wheat protein and eggs) and fiber (cellulose, pectin, wheat fiber and carrot fiber) typically consumed by Americans. The resulting diets will be used to conduct studies described in Objective 1 evaluating the effects of these diets on the microbiome, metabolome, gene expression and resistance to colitis. Initiating the animal studies is contingent on having an Attending Veterinarian in place to approve animal protocols describing the proposed studies.
Breeding of Ossabaw pigs needed for proposed experiments under Objective 3 is contingent to have attending Veterinarian to approve import of animals.
Most nutritional studies use diets that do not reflect what is consumed by a typical American. We have been using a Total Western Diet (TWD) whose macro- and micronutrient composition is based on 50 percentile intake from NHANES data to better reflect what an average American consumes. However, the TWD only has one source of protein, casein, and one source of fiber, cellulose. To address this shortcoming, we are developing modified versions of the TWD that have multiple sources of protein and fiber. We are working with Dr. Korry Hintze at Utah State University and Nicole Tiry, a nutritionist with Inotivico on formulating TWDs to include sources of protein (casein, whey, chicken, beef, wheat protein and eggs) and fiber (cellulose, pectin, wheat fiber and carrot fiber) typically consumed by Americans. The resulting diets will be used to conduct studies described in Objective 1 evaluating the effects of these diets on the microbiome, metabolome, gene expression and resistance to colitis. Initiating the animal studies is contingent on having an Attending Veterinarian in place to approve animal protocols describing the proposed studies.
Breeding of Ossabaw pigs needed for proposed experiments under Objective 3 is contingent to have attending Veterinarian to approve import of animals.
Accomplishments
Review Publications
Smith, A.D., Chen, C.T., Cheung, L., Ward, R., Jones, B., Pletsch, E.A., Dawson, H.D. 2024. A type 4 resistant potato starch alters the cecal microbiome and gene expression in mice fed a Western diet based on NHANES data. Nutrients. 15:3141-3157. https://doi.org/10.1039/d3fo04512a.
Liu, F., Smith, A.D., Wang, T.T., Pham, Q., Hou, P., Cheung, L., Yang, H., Li, R.W. 2024. Phospholipid-rich krill oil promotes intestinal health by strengthening beneficial gut microbial interactions in an infectious colitis model. Food & Function. 15(5):2604-2615. https://doi.org/10.1039/D3FO04980A.