Products of
arachidonic acid metabolism are elevated in patients with
inflammatory bowel disease and this elevation is correlated with disease activity.
Eicosapentaenoic acid competes with
arachidonic acid and alters
eicosanoid biosynthesis. In this experiment, the possibility that
eicosapentaenoic acid could be used in the treatment of
inflammatory bowel disease was investigated by determining the effect of 6 weeks of a
fish oil-supplemented diet, enriched in
eicosapentaenoic acid, on colonic and ileal morphology, histology, and in vivo fluid absorption in rats with 4%
acetic acid-induced
colitis. The results of an
eicosapentaenoic acid-enriched diet were compared with results of saturated and
polyunsaturated fatty acid-enriched diets. In rats with
misoprostol pretreated
acetic acid-induced
colitis, an
eicosapentaenoic acid-enriched diet reversed net colonic fluid secretion to absorption and prevented macroscopic and histologic injury, compared with saturated and poly-
unsaturated fatty acid-enriched diets, which did not. The
fish oil mucosal protective effect occurred in the presence of a 30-fold enhancement of
PGE2 synthesis. In rats with non-
misoprostol pretreated
acetic acid-induced
colitis, an
eicosapentaenoic acid-enriched diet returned ileal fluid absorption to control levels, as compared with saturated and
polyunsaturated fatty acid-enriched diets, which did not. In conclusion, a
fish oil (
eicosapentaenoic acid)-enriched diet, but not a saturated- or a polyunsaturated-enriched diet, protected colonic and ileal net fluid absorption in an experimental model of
inflammatory bowel disease.