Download Full Text (828 KB)
Colorectal cancer is currently the second leading cause of cancer-related deaths in the United States and is projected to cause 53,200 deaths during 2020. The risk of colon cancer increases by 8-20% in individuals who suffer from colitis, which is inflammation of the colon lining. Colitis is common in patients with inflammatory bowel disease (IBD), including Crohn's disease and ulcerative colitis. The development of colorectal cancer is complex and can be associated with dysbiosis of the gut microbiota, which has been shown to be affected by diet. Disruption of the gut microbiome can lead to the overgrowth of pathogenic bacteria which can contribute to disease. Pathogenic bacteria and other bacterial byproducts that manage to cross the epithelial barrier, trigger the immune system. Small, nonstructural proteins called cytokines are critical to immune response and may have either pro-inflammatory or anti-inflammatory effects. Two cytokines involved in inflammatory response associated with the development of colitis-associated colorectal cancer include IL-6 and IL-17. IL-6 is released by immune cells in response to some other inflammatory cytokines as part of the pro-inflammation signaling pathway that is often active in many chronic disease conditions associated with inflammation. Similarly, IL-17 is also a pro-inflammatory cytokine produced by a specific population of immune cells called T helper 17 cells that play an important role in maintaining the mucosal barrier of the intestine and help clear pathogens. The goal of this study is to determine the blood concentrations of certain cytokines in mice fed either healthy diet (AIN93G) or a Western style diet (TWD) prior to, during, and after colitis, as well as during tumorigenesis. Concentration of the two cytokines in blood samples will be determined using a commercial enzyme-linked immunosorbent assay (ELISA) kit obtained from ThermoFisher. Data collection and analyses are still ongoing. Data will be analyzed using a standard linear mixed model for diet treatment, time point, and diet x time point with cage as a nested random factor. We expect blood levels of IL-6 and IL-17 to increase in animals fed a TWD diet indicating higher levels of colitis, and the levels to remain elevated through recovery and tumorigenesis. If our hypothesis is correct, the finding that IL-6 and IL-17 are increased in mice fed the TWD would suggest potential adverse systemic inflammation due to prolonged elevated cytokine release.
Utah State University
Life Sciences | Nutrition
Mortensen, Emily, "Cytokine Indicators of Inflammation in Mice Fed a Western Type Diet" (2020). Fall Student Research Symposium 2020. 56.