Bioactive Fatty Acids Reduce Development of Gastric Cancer Following Duodenogastric Reflux in Rats

Abstract

Background: Bioactive fatty acids such as the eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) and the modified fatty acid analogue, tetradecylthioacetic acid (TTA), are known to influence inflammatory processes in the body. Our aim was to investigate if diets containing fish oil (FO) enriched with bioactive fatty acids could affect inflammation and development of glandular stomach carcinogenesis in a duodenogastric reflux (DGR) animal model. We also wanted to evaluate if a high-fat diet might increase the risk of developing gastric cancer compared to a low-fat diet. Methods: 185 rats operated on with a gastroenterostomy were randomly allocated to 5 different treatment groups given: low-fat, high-fat, high-fat + FO, high-fat + TTA or high-fat + FO + TTA. The stomachs were removed after 50 weeks and examined by light microscopy with hematoxylin and eosin staining (HE). Immunohistochemical staining against COX-2, PCNA and p53 was performed when adenocarcinomas were found. The plasma fatty acid profile was determined. Results: Adenocarcinomas developed in 21% of animals fed the low-fat diet, 35% in the high-fat group, 16% in the high-fat + TTA group, 21% in the high-fat + FO group and 8.6% in the high-fat + FO + TTA treatment group. COX-2 and PCNA were positive whereas p53 was negative in the majority of the samples. The anti-inflammatory fatty acid index increased after treatment with FO and in combination with FO and TTA. Conclusion: FO and TTA in combination with a high-fat diet significantly lower the risk of developing adenocarcinomas in rats subjected to duodenogastric reflux. This is most likely due to a selective modulation of inflammation.

Peroxisome Proliferator-Activated Receptor Activation is Associated with Altered Plasma One-Carbon Metabolites and B-Vitamin Status in Rats

“…The diets had the same amounts of micronutrients, and the rats had free access to water and feed during the study period. The animals investigated were part of a larger study, and more detailed descriptions of this experiment and the composition of the diets have previously been published [ 27 ]. Feed intake was comparable between groups, but the TTA treated rats gained less weight as compared to Controls [ 28 ].…”

Long-term treatment with the pan-PPAR agonist tetradecylthioacetic acid or fish oil is associated with increased cardiac content of n-3 fatty acids in rat

“…These animals were part of a larger study [ 47 ], where they all underwent a jejuno-gastric reflux surgical procedure. A separate experiment enduring 11 weeks were done comparing animals with and without operation, to make sure that the procedure did not affect the nutritional state in the animals.…”