Reduction in formation and growth of 1,2-dimethylhydrazine-induced aberrant crypt foci in rat colon by docosahexaenoic acid.

The effect of intragastric gavage administration of docosahexaenoic acid (DHA) on the formation of 1,2-dimethylhydrazine (DMH)-induced aberrant crypt foci in rat colon was investigated. Male F344 rats were treated three times s.c. with 20 mg/kg of DMH and were given either 0.7 ml of DHA or water intragastrically 5 times a week for 4, 8, or 12 weeks from the day before the first carcinogen treatment. The numbers of DMH-induced aberrant crypt foci per colon after 4, 8, and 12 weeks of DHA treatment were approximately 40% of those in the respective control groups, and the differences were statistically significant. The numbers of foci reached plateau levels at 8 weeks in both the DHA-treated and control groups. The mean number of aberrant crypts per focus was also significantly smaller in the group given DHA than that in the control group at each time. These results suggest that DHA suppresses the formation and growth of aberrant crypt foci and has a preventive effect on colon carcinogenesis.