Emu Oil and Zinc Monoglycerolate Influence the Course of Disease in a Rat Model of Ulcerative Colitis

Background: Ulcerative colitis is characterized by colonic inflammation. Previously, Emu Oil protected the intestine against experimentally-induced inflammatory intestinal disorders. Zinc monoglycerolate (ZMG) polymer, formed by heating zinc oxide with glycerol, demonstrated anti-inflammatory and wound healing properties. Objective: We aimed to determine whether ZMG, alone or in combination with Emu Oil, could reduce acute colitis severity in rats. Methods: . Male Sprague Dawley rats (n=8/group) were orally-administered either vehicle, ZMG, Emu Oil (EO) or ZMG combined with EO (ZMG/EO) daily. Rats were provided ad libitum access to drinking water (Groups 1-4) or dextran sulphate sodium (DSS; 2%w/v; Groups 5-8) throughout the trial (days 0-5) before euthanasia on day 6. Disease activity index, crypt depth, degranulated mast cells (DMCs) and myeloperoxidase activity were assessed. p<0.05 was considered significant. Results: . DSS increased disease severity (days 3-6) compared to normal controls (p<0.05). Importantly, in DSS-administered rats, ZMG reduced disease activity index (day 6) compared to controls and EO-treated rats (p<0.05). Following DSS consumption, distal colonic crypts lengthened (p<0.01), occurring to a greater extent with EO compared to ZMG and ZMG/EO (p<0.001). DSS increased colonic DMCs compared to normal controls (p<0.001); an effect decreased only by EO (p<0.05). Colonic myeloperoxidase activity increased following DSS consumption (p<0.05); notably, ZMG, EO and ZMG/EO treatments decreased myeloperoxidase activity compared to DSS controls (p<0.001). EO, ZMG and ZMG/EO did not impact any parameter in normal animals. Conclusions: . Emu Oil and ZMG independently decreased selected indicators of colitic disease severity in rats; however, the combination did not reveal any additional benefit.