Experimental inflammatory bowel disease in western diet fed rats

BACKGROUND: The etiology of inflammatory bowel disease (IBD) is still not well known. Recent studies however, have clearly demonstrated that both environmental and genetic factors play a role in the development of the disease. This study aimed at developing a chronic IBD model in western diet fed rats using a combination treatment of Iodoacetamide and bacteria. METHODS: 110 Male Sprague‐Dawley rats were given a western diet since birth and at adulthood were divided into 4 groups and inoculated according to a weekly schedule with: 1‐ methylcellulose, 2‐ Iodoacetamide, 3‐Iodoacetamide + bacteria, 4 bacteria alone. Rats were observed on a daily basis for clinical signs and symptoms (diarrhea, weight loss, bloody stools...). Descending colons (DC) tissues and mucosal scrapings were removed for light microscopic studies, as well as RNA and protein extraction for cytokine level determination. RESULTS: Results showed a successful development of an IBD experimental model with repetitive treatments in groups 2 and 3 whereby a decrease in weight gain as well as diarrhea and loose bloody stools were observed. In addition, histological changes confirmed the development of ulcers Althrough the 42 days of the study. Inflammation signaling through Tumor Necrosis Factor alpha and Interleukin 1 beta were elevated in particular in the second and third groups. Preliminary studies carried out on gap junctions showed changes in epithelial cell to cell communication in this model. Supported by a grant from the Lebanese National Science Research Council