Effect of an omega-3 lipid emulsion in reducing oxidative stress in a rat model of intestinal ischemia−reperfusion injury

OBJECTIVES: The usefulness of omega-3 lipid emulsions has been extensively studied. The objectives of the present study were to examine the effect of an omega-3 lipid emulsion in reducing oxidative stress in a rat model of intestinal ischemia−reperfusion injury and the underlying mechanism. METHODS: A total of 66 rats were divided into three dietary groups (lipid-free, soybean oil, and fish oil groups). Each animal was administered total parenteral nutrition for 3 days, followed by induction of intestinal ischemia for 100 min. Animals subjected to sham surgery served as the controls. Intestinal tissue and blood were harvested 6 and 12 h after the surgery, then, assessment of the histological damage score, plasma-related parameters, and statistical evaluation were performed. RESULTS: The histological damage score in the intestinal tissues was significantly lower in the fish oil group than in the soybean oil group (P = 0.0121). The late-phase urinary level of 8-hydroxy-2-deoxyguanosine was also significantly lower in the fish oil group as compared with that in the other groups (P = 0.0267). Furthermore, the plasma level of high-mobility group box 1 protein was also significantly lower in the fish oil group as compared with that in the lipid-free group (P = 0.0398). CONCLUSION: It appeared that intravenous administration of an omega-3 lipid emulsion prior to ischemia−reperfusion injury reduced the oxidative stress and severity of tissue damage. Modification of membrane fatty acids may serve as the mechanism underlying this reduction of tissue damage.