Diet And Antibiotic Influences On Mice Induced With Dss Colitis And Their Gut Flora

Open Access
Author:
Innes, Gabriel Keller
Area of Honors:
Veterinary and Biomedical Sciences
Degree:
Bachelor of Science
Document Type:
Thesis
Thesis Supervisors:
  • Margherita Teresa Anna Cantorna, Thesis Supervisor
  • Lester C Griel Jr., Honors Advisor
Keywords:
  • Colitis
  • Microflora
  • Gut
  • DSS
  • Fiber
  • Mice
  • Diet
Abstract:
Inflammatory bowel disease causes a variety of problems in patients. The most obvious is the serious degradation of the intestinal tract. It has been shown that specific diets have ameliorated as well as aggravated the intestinal lining. The specific mechanism and reason for this exacerbation is relatively unknown, however there are notably two possibilities: diet influences gut flora, promoting helpful bacteria or decreasing harmful ones; or that the diet has an impact upon the host’s immune system, compromising the host. First, the diets’ (specifically types of carbohydrates) effects in mice induced with a mouse model of inflammatory bowel syndrome called dextran sulfate sodium (DSS) was investigated. To understand the central cause of inflammation, the successive study utilized antibiotics to alter the composition of the bacteria flora in the gut and examine how it affects symptom severity of DSS colitis. Through the analysis of weight change, fecal DNA, as well as colon length changes, the correlation between gut flora can be studied. Three diets were used: Chow (CD, LabDiet 5001), Harlan Teklad (TD, TD96348), and a purified diet (PD) (made in the laboratory). There are multiple differences in the diets’ composition. The CD diet contained the greatest diversity of fiber. The TD diet, with significant makeup of starch, lactose, and fiber (cellulose) had the most negative effects on the mice induced with DSS. Conversely, the mice fed PD, with dextrose and sucrose, and less fiber, proved to perform better all around, while mice fed TD performed significantly worse. This was determined via relative weight changes, as well as colon shrinkages. After this, antibiotics were introduced in the mice’s water with either TD or PD. The influence of antibiotics had a greatly positive consequence on mice given both types of diets, highly outperforming their control counterparts. This promotes the theory that the gut flora largely controls the inflammation of the gut.