Inflammatory bowel disease in rats： Bacterial and chemical interaction

• Published in: World journal of gastroenterology : WJG Vol. 14; no. 25; pp. 4028 - 4039
• Main Authors: Hajj Hussein, Inaya-Abdallah, Tohme, Rania, Barada, Kassem, Mostafa, Mostafa Hassan, Freund, Jean-Noel, Jurjus, Rosalyn A, Karam, Walid, Jurjus, Abdo
• Format: Journal Article
• Language: English
• Published: United States Faculty of Science, 115020 Beirut Arab University, Beirut, Lebanon%Faculty of Medicine, 110236/41 Riad El-Slaleh, 1107-2020 American University of Beirut, Beirut, Lebanon%Faculty of Science, 115020 Beirut Arab University, Beirut, Lebanon%INSERM 682, Ontogenese et pathologie du system digestif, Strasbourg, France%Institut National De Pathologic, Beirut, Lebanon 07-07-2008; Faculty of Medicine, 110236/41 Riad El-Slaleh, 1107-2020 American University of Beirut, Beirut, Lebanon; Baishideng Publishing Group Co. Limited; The WJG Press and Baishideng
• Subjects: Animals; Basic Research; Cancer; Colitis, Ulcerative - chemically induced; Colitis, Ulcerative - metabolism; Colitis, Ulcerative - microbiology; Colitis, Ulcerative - pathology; Colon, Descending - drug effects; Colon, Descending - enzymology; Colon, Descending - microbiology; Colon, Descending - pathology; Disease Models, Animal; Enteropathogenic Escherichia coli; Iodoacetamide; Life Sciences; Male; Peroxidase - metabolism; Rats; Rats, Sprague-Dawley; Reproducibility of Results; RNA, Messenger - metabolism; Time Factors; Tumor Necrosis Factor-alpha - genetics; Tumor Necrosis Factor-alpha - metabolism; 临床表现; 化学治疗; 炎症肠疾病; 碘乙酰胺; Inflammatory bowel disease model; Iodoacetamide; Gastrointestinal inflammation; Colitis; Escherichchia coli
• ISSN: 1007-9327; 2219-2840
• DOI: 10.3748/wjg.14.4028

AIM：To develop a novel model of colitis in rats, using a combination of iodoacetamide and enteropathogenic E. coli（EPEC）, and to elucidate the pathophysiologic processes implicated in the development of ulcerative colitis （UC）.
METHODS： Hale Sprague-Dawley rats （/7 = 158） were inoculated intrarectally on a weekly basis with 4 different combinations： （a） 1% methylcellulose （HC）, （b） 100 μL of 6% iodoacetamide （IA） in 1% HC, （c） 200 p.L containing 4×10^8 colony factor units （CFU） of EPEC, and （d） combined treatment of （IA） followed by bacteria （13） after 2 d. Thirty days post treatment, each of the four groups was divided into two subgroups; the inoculation was stopped for one subgroup and the other subgroup continued with biweekly inoculation until the end of the experiment. Colitis was evaluated by the clinical course of the disease, the macroscopic and microscopic alterations, activity of myeloperoxidase （HPO）, and by TNF-α gene expression. RESULTS： Findings indicative of UC were seen in the combined treatment （IA ＋ B） as well as the IA continued treatment groups： the animals showed slow rate of increase in body weight, diarrhea, bloody stools, high colonic ulcer score, as well as histological alterations characteristic of UC, with an extensive inflammatory reaction. During the course of the experiment, the MPO activity was consistently elevated and the TNF-α gene expression was upregulated compared to the control animals.
CONCLUSION： The experimental ulcerative colitis model used in the present study resembles, to a great extent, the human disease. It is reproducible with characteristics indicative of chronicity.