: Recent studies have suggested that
n-3 fatty acids from
fish oil (FO) as well as
short-chain fatty acids may attenuate some of the gut injury and inflammationassociated ulcerative colitic (UC). The objectives of this study were to (a) assess the antiinflammatory activity of
sulfasalazine (SAZ), a
drug known to be effective in the treatment of human UC in a model of chronic
granulomatous colitis in rats and (b) determine whether enteral diets supplemented with either FO or two indigestible
oligosaccharides (
fructooligosaccharide, FOS;
xylooligosaccharide, XOS) could attenuate the
inflammation observed in a model of chronic
granulomatous colitis. In one series of experiments, female Lewis rats were randomized into three groups consisting of a
sham-operated control group, a colitic group, and a colitic group in which rats were given oral
sulfasalazine (SAZ) immediately after induction of
colitis and continued for 3 weeks. Chronic
granulomatous colitis with liver and spleen
inflammation was induced by subserosal (intramural) injection of purified
peptidoglycan-
polysaccharide (PG/PS) into the distal colon.
Sham-operated rats were injected with
human serum albumin. All rats received standard lab chow. In a second series of experiments, female Lewis rats were randomized into six groups consisting of four colitic groups fed enteral diets, a colitic group fed chow, and a
sham-operated group fed a control enteral diet. Enteral diets (300 kcal/kg/day) contained either FO, FOS/
gum arabic, XOS/
gum arabic, or no bioactive ingredient (control diet). All rats were fed for 1 week before induction of
colitis. Rats consumed the diets for 3 additional weeks before being killed. SAZ significantly attenuated the PG/PS-induced increases in
myeloperoxidase (MPO) activity as well as significantly reduced the PG/PS-induced increases in liver and spleen weights. Control (enteral diet) as well as the FO and XOS diets significantly attenuated the increase in colon weight when compared with chow-fed rats. We also found that the FO and XOS diets significantly attenuated the PG/PS-induced increases in colonic MPO activity and colon weight. The FOS and XOS diets significantly attenuated the PG/PS-induced increases in liver weights when compared with PG/PS + chow-fed animals. The antiinflammatory activity of these diets was confirmed by means of histological inspection showing an inhibition of
inflammation and maintenance of crypt cell integrity. These results demonstrate that a complete enteral diet supplemented with either FO, FOS, or XOS exhibited antiinflammatory activity that was similar in efficacy to the known antiinflammatory
drug SAZ in this model of
colitis.