Effect of omega-3 versus omega-6 fatty acids on induced ulcerative colitis in male albino rat. Light and electron microscopic study

ABSTRACT

Ulcerative colitis [UC] is an inflammatory bowel disease [IBD] well known by its exacerbated immune response. At present, a specific causal treatment for IBD is not available. The drugs currently used for management of IBD unfortunately are not devoid of potentially serious side effects. Polyunsaturated fatty acids [PUFAS] as omega-3 and omega-6 were reported to have immunomodulatory activities. Hence, may be of benefit in treating UC. The goal of this study was to illustrate the effect of omega-3 and omega-6 fatty acids on ulcerative colitis induced in male albino rat. Thirty adult male albino rats were used in the study. They were divided into four groups; Group I served as a control group. Group II was used as a model of ulcerative colitis. Rats of this group were subjected to intracolonic enema injection of 1 ml of 2% acetic acid for three consecutive days. Group III and group IV were subjected to colitis induction and on the fourth day, daily oral administration of omega-3 and omega-6 was done respectively for 14 days. All rats were sacrificed on day 17 from the beginning of the experiment. Colon specimens were collected and processed for light microscopic, scanning and transmission electron microscopic examination. Ulcerative colitis induction showed mucosal injury. There were patchy areas with loss of crypt architecture, inflammatory cell infiltrate and ulcerated mucosa. Scanning electron microscopic study revealed areas of ulceration, whereas other areas showed alteration of the columnar absorptive cells. Transmission electron microscopic study revealed loss of apical microvilli of enterocytes with signs of degeneration. Administration of omega-3 completely treated the colonic structure, while omega-6 was by far less efficient in treating induced ulcerative colitis. Omega-6 fatty acids partially improved the colon against ulcer induction. Meanwhile, omega-3 fatty acid proved to be a more effective dietary management of ulcerative colitis without the adverse effects of either surgery or medications