Chemopreventive effects of dietary flaxseed on colon tumor development.
Cast your vote
You can rate an item by clicking the amount of stars they wish to award to this item.
When enough users have cast their vote on this item, the average rating will also be shown.
Your vote was cast
Thank you for your feedback
Thank you for your feedback
MetadataShow full item record
AbstractFatty acid composition of dietary fat plays a vital role in colon tumor development in animal models. Fats containing omega-6 fatty acids (e.g., corn oil) enhanced and omega-3 fatty acids (e.g., flaxseed oil) reduced chemically induced colon tumor development in rats. Lignans have also been shown to prevent colon tumor development in experimental animals. The objective of this investigation is to study the effects of dietary flaxseed meal, a source of both omega-3 fatty acid and lignans, on colon tumor development and compare them with the effects of dietary corn meal. Male Fischer rats, two groups of 24 each, were assigned to the AIN-93M diet supplemented with either 15% corn meal or 15% flaxseed meal, respectively. Carcinogenesis was initiated with subcutaneous injections of azoxymethane (15 mg/kg) once a week for 3 consecutive wk. After 35 wk of initiation, rats were anesthetized with ether. Blood was collected by cardiac puncture, and rats were sacrificed. The gastrointestinal tract was isolated. The site, size, and number of tumors were recorded. The fatty acid analysis of the collected serum and colon samples was performed. Expression of cyclooxygenase (COX)-1 and COX-2 was performed by Western blot method. Lignan levels in serum and colon samples were assayed. Colon tumor incidence, multiplicity, and size were found to be 82.6% and 29.4%; 1.3 and 0.3; and 44.4 and 5.3 mm(2) in corn and flaxseed meal groups, respectively. Colon and serum samples of the corn meal group showed higher levels of omega-6 fatty acid levels whereas the flaxseed meal group exhibited higher levels of omega-3 fatty acids. COX-1 and COX-2 expression in the flaxseed group was significantly lower (P < 0.05) as compared to the corn group. Dietary flaxseed meal containing high levels of omega-3 fatty acids and lignans is effective in preventing colon tumor development when compared with dietary corn meal possibly by increasing omega-3 fatty acid levels and decreasing COX-1 and COX-2 levels.
CitationNutr. Cancer 2006, 54 (2):216-222
JournalNutrition and Cancer
DescriptionDietary modulation of cancer & cancer biomarkers; Dietary modulation of carcinogenesis-related pathways. Dietary item or component studied: flaxseed oil. Outcome studied: colon cancer risk; expression of cyclooxygenase (COX)-1; expression of COX-2. Study type: male Fischer rats Tissue/biological material/sample size: colon, blood. Impact on outcome (including dose-response): Colon tumor incidence, multiplicity, and size were found to be 82.6% and 29.4%; 1.3 and 0.3; and 44.4 and 5.3 mm(2) in corn and flaxseed meal groups, respectively. Colon and serum samples of the corn meal group showed higher levels of omega-6 fatty acid levels whereas the flaxseed meal group exhibited higher levels of omega-3 fatty acids. COX-1 and COX-2 expression in the flaxseed group was significantly lower (P < 0.05) as compared to the corn group. Keywords - classification: administration & dosage;adverse effects;analysis;Animals;Azoxymethane;blood;Carcinogens;chemically induced;chemistry;Colon;Colonic Neoplasms;Corn Oil;Cyclooxygenase 1;Cyclooxygenase 2;Dietary Fats;Dietary Fats,Unsaturated;dietary modulation of cancer & cancer biomarkers;dietary modulation of carcinogenesis-related pathways;Fatty Acids;Fatty Acids,Omega-3;Fatty Acids,Omega-6;Flax;humans;Lignans;Male;metabolism;pathology;pharmacology;prevention & control;Random Allocation;Rats;Rats,Inbred F344;Research;toxicity;