The Distribution Of ω-3 Polyunsaturated Fatty Acid In The Gut, The Absorption In The Body And Anti-inflammatory Effects

ω-3 PUFAs was an essential fatty acid in human body. Several studies indicated that the ω-3 PUFAs and the ratio of ω-6/ω-3 play a very important role in human health. It is well known that the intestinal tract is the main organ to absorb the fatty acids and the intestinal bacteria are important for immune protection. Nonetheless, the detailed distribution of fatty acids along the gut has not been reported. Here we investigate the influence of ω-3 PUFAs on the distribution of fatty acids in the gut and the absorption of EPA and DHA in the vivo and the different role of anti-inflammatory effect of EPA and DHA. Our results will provide a foundation for the future ω-3 PUFAs supplementation in the food industry.We feed mice with different ratio of ω-6/ω-3 diet and blood was collected at different time point. At the end of the experiments, the gut, liver, prostate and epididymal fat pad tissues were dissected and the fatty acid composition was analyzed by GC/MS, and the infiltration of inflammatory cells were analyzed by the immunohistochemistry method. Human trial was conducted to confirm the results from animal studies. The main conclusion are as follows:(1) the effect of dietary ω-3 PUFAs on the distribution of fatty acid in the gutIn order to systematically analyze the gut fatty acid composition, the small intestines were divided into 12 equal length segments, ceca as one segment and colons were separated into four equal length segments; the segment were numbered 1-17 along the gut. The percent composition of PUFAs, MUFAs, SFAs, ω-3PUFAs, ω-6 PUFAs, EPA and DHA along the gut were gradually lower. And the downtrend of EPA content was higher than DHA content. The different ratio of ω-6/ω-3 could significantly affect the distribution of fatty acid in the intestinal tract. The supplement of ω-3 PUFAs increased the level of ω-3 PUFAs in the whole gut. These result will support the study of fatty acid absorption in the gut and the interaction between intestinal bacteria and ω-3 PUFAs in the future.(2) the effect of dietary ω-3 PUFAs on the content of fatty acid in the blood and related tissuesAlthough ω-3 PUFAs did not affect the total levels of PUFAs, MUFAs and SFAs in the blood, but the content of ω-3 PUFAs, ω-6 PUFAs, EPA and DHA had been changed significantly. Meanwhile the different ratio of ω-6/ω-3 had also significantly affected the fatty acid composition in liver, prostate and epididymal fat pad tissues specifically. In addition, the baseline of EPA was lower than DHA. But the increase of the percent composition of EPA was higher than DHA by the dietary supplement of EPA and DHA.(3) the effect of ω-3 PUFAs on the inflammatory cells in the prostate tissuesThe immunohistochemistry method was used to analyze the infiltration of inflammatory cells in prostate tissues. Compared to ω-6 group, DHA and EPA could reduce the infiltration of T lymphocyte by 25.5 % and 77.3 %; B lymphocyte by 41.8 % and 74.3 %; macrophage by 22.2 % and 74.3 %. Controry to DHA, EPA could inhibit the infiltration of T, B lymphocyte and macrophage to reduce levels of inflammation and delay the development of prostate cancer.(4) the effect of supplementation of fish oil on the content of EPA and DHA in human bodyCompared to DHA, our result showed that EPA level is very low in human body, which was similar to the levels of EPA and DHA in mice. It may caused by lacking of dietary supplement or the rapid metabolism. Therefore, supplementation of ω-3 PUFAs in human to increase EPA level is effective and necessary.In summary the results from this project found that dietary supplement of ω-3 PUFAs can boost bioavailability of ω-3 PUFAs along the gut, the level of EPA, and inhibit the inflammatory reaction in the body. Meanwhile the human trial indorsed that the body was in a state of lacking EPA, which provided a foundation for the supplement in the food industry.