ω-3 fatty acids attenuate mucosal inflammation in premature rat pups.

BACKGROUND: Necrotizing enterocolitis (NEC) is a devastating intestinal disease of premature infants. Although ω-3 fatty acids are known to have antiinflammatory effects, their effect against NEC remains unclear. METHODS: Mother rats fed a soybean-based, docosahexaenoic acid (DHA)- or eicosapentaenoic acid (EPA)-enriched diet from days 7 to 20 of gestation were examined. On day 20, the rat pups were delivered by abdominal incision, their intestines were removed, and messenger RNA was extracted. A rat NEC model was used to confirm the effects of ω-3 fatty acids on the inflamed intestine (n = 20-28). The expression of inflammatory molecules was analyzed by real-time polymerase chain reaction (n = 11-14). RESULTS: The concentrations of DHA and EPA in the intestine were significantly increased in the DHA and EPA groups (P < .01). The expression of the antiinflammatory prostaglandin E2 receptor EP3 was increased in the DHA (P < .05) and EPA groups (P < .01). In the NEC model, the reduced incidence of colitis was confirmed in the DHA and EPA groups. The expression of peroxisome proliferator-activated receptor γ was increased (P < .05), and the inhibitor of nuclear factor-κB α/ß decreased in both the DHA (P < .01) and EPA groups (P < .05). CONCLUSION: Our findings indicate that ω-3 fatty acids are beneficial for protecting the premature intestine from inflammation by regulating eicosanoid- and nuclear factor-κB-related metabolite expression.

Effects of alpha-linolenic acid on colonic secretion in rats with experimental colitis.

BACKGROUND: Few studies have specifically examined the effects of n-3 polyunsaturated fatty acids (PUFAs) on intestinal water and ion secretion in ulcerative colitis (UC). The aim of this study was to examine the contribution of prostaglandins (PGs) and leukotrienes (LTs) to mucosal secretion in intestines with UC and to evaluate the effect of dietary n-3 PUFAs on diarrhea in UC. METHODS: We measured the short-circuit current (Isc), using the Ussing chamber method, and fatty acid composition in the colonic mucosa of rats with dextran sulfate sodium (DSS)-induced experimental colitis. The DSS-treated rats were fed either a perilla oil-enriched diet (perilla group) or a soybean oil-enriched diet (soybean group); a control group did not undergo DSS administration. RESULTS: The bradykinin-stimulated DeltaIsc in the soybean and perilla groups was significantly higher than that in the control group. The mucosal level of arachidonic acid in the perilla group was significantly lower than that in the soybean group. The mucosal levels of alpha-linolenic acid and EPA in the perilla group were significantly higher than those in the soybean group. The bradykinin-stimulated DeltaIsc was significantly suppressed after pretreatment with indomethacin in both the soybean and perilla groups, and was also significantly reduced in both groups after pretreatment with AA861. The suppression of bradykinin-stimulated DeltaIsc by the addition of AA861 was significantly higher in the perilla group than in the soybean group. CONCLUSIONS: Our results suggest that supplementation with alpha-linolenic acid, in combination with a lipoxygenase inhibitor, could suppress the increase in Cl- secretion in patients with UC.