An enteral formula containing fish oil, indigestible oligosaccharides, gum arabic and antioxidants affects plasma and colonic phospholipid fatty acid and prostaglandin profiles in pigs

Evidence supports a pathogenic role of arachidonic acid - derived inflammatory mediators within the gastrointestinal tract of patients with inflammatory bowel disease. The purpose of this study was to assess the effects of an ulcerative colitis nutritional formula (UCNF) containing oligosaccharides, fish oil, gum arabic and antioxidants on plasma and colonic phospholipid fatty acid and prostaglandin profiles in pigs. Twenty-four growing barrows in two replications were equally randomized among four killing times (d 0, 7, 14 and 21), and one of two diets, a control and the UCNF. Diets contained comparable levels of protein, fat, and nonstructural carbohydrate and met 100% of the energy requirements of the pig. Intake and body weight were recorded daily while blood, urine and tissue samples were collected at time of kill. Within 1 wk of ingestion of the UCNF, the composition of plasma phospholipid fatty acids showed an increase in 20:5(n-3) and 22:6(n-3) (P < 0.0001) and a decrease in 20:4(n-6) and 18:2(n-6) (P < 0.0001). Similar effects were observed for the phospholipids in the colonic and cecal mucosa. Plasma prostaglandin E was unaffected by treatment, whereas thromboxane [B.sub.2] and 6-ketoprostaglandin [F.sub.1[Alpha]] levels were significantly decreased after 7 d of UCNF ingestion. Ingestion of the UCNF resulted in a suppression in the synthesis of proinflammatory prostaglandins by cecal and colonic mucosal cells. Levels of colonic and cecal prostaglandin E, 6-ketoprostaglandin [F.sub.1[Alpha]] and thromboxane [B.sub.2] were significantly decreased after 7 d of UCNF ingestion. These changes may have been mediated by rapid increases of (n-3) fatty acids into cellular phospholipids. Dietary supplementation with the UCNF may prove beneficial for patients with ulcerative colitis by modulating colonic prostaglandin synthesis. J. Nutr. 127: 137-145, 1997. KEY WORDS: fish oil oligosaccharides pigs inflammatory bowel disease ulcerative colitis