Protective effect of olive oil against benzo(a)pyrene (BaP)‐ induced colon tumor development and BaP biotransformation in ApcMin mice

Abstract

Benzo(a)pyrene (BaP) is a widely distributed environmental toxicant. Since sporadic colon cancers are triggered by diet and environment, our studies were aimed at understanding the role of BaP in the development of colon cancer. In this study we investigated the effect of olive oil on BaP‐induced colon carcinogenesis in male ApcMin mice. Mice were assigned to a control (n =7) or treatment group (n =7). Treatment consisted of 50 and 100 μg BaP/kg body weight dissolved in tricaprylin (BaP‐only group) or olive oil administered daily via oral gavage for sixty days. Post exposure, mice were sacrificed; colon and liver tissues were retrieved and preserved for evaluation of pathological changes and further analyzed for the induction of cytochrome 1A1 and 1B1 drug metabolizing enzymes. A reduced incidence of adenomas in colons of mice that ingested BaP through olive oil compared to controls (p < 0.05) was seen. In addition, CYP protein expression was reduced in the colon and liver tissues of olive oil treated mice compared to BaP‐treated mice. In summary, our studies suggest that olive oil exerts a protective effect against BaPinduced colon cancer (funded by NIH grants 5R25GM059994–11 and 5R01CA142845–01A1).