Dietary Combinations of Wheat Bran, Flax, and Soy Reduce ACF in Rat Model

摘要

Certain dietary fibers have been shown to reduce the incidence of colon tumors in rats fed high-fat diets. Although insoluble fibers are most commonly associated with this anticancer potential, certain soluble fibers, such as psyllium, flaxseed, and soybean, have also been shown to inhibit chemically induced colon cancer in rodents. The main purpose of this research was to evaluate the effect of wheat bran, flaxseed, and soybean alone and in combination on azoxymethane (AOM, Sigma Chemical Co., St. Louis, MO, U.S.A.)-induced colon tumorigenesis in Fisher-344 rats maintained on high-fat diets. A total of 165 male Fisher-344 rats was divided into 11 test diet groups. After three weeks on test diets, the rats were given injections of ethane AOM (15 mg/kg of body weight) and remained on their respective experimental diets until kiUed by exsan-guination under anesthesia at week 10. The colons were removed and prepared for evaluation of colonic aberrant crypt formations (ACF). Results indicate that bothinsoluble (wheat bran) in various combinations with soluble (soy, flax) fibers significantly reduced both the number and size of ACF. The soybean diet resulted in a significant decrease (p < 0.05) in the number of ACF compared with wheat bran or flax. ACF incidence and multipHcities were significantly reduced (p < 0.05) in dietary groups including flax and wheat bran fiber in combination with soybean.