Olive oil and omega-3 polyunsaturated fatty acids suppress intestinal polyp growth by modulating the apoptotic process in ApcMin/+ mice

Abstract

The promotion and progression of carcinogenesis are susceptible to nutritional interventions aimed at counteracting cancer development. Lipid metabolism is essential in the onset and progression of tumours as well as for cancer cell survival. In the present study we tested the effects of diets enriched with natural compounds, such as olive oil and salmon oil, in mice that spontaneously develop intestinal polyps (ApcMin/+ mice). For this purpose we evaluated polyp number and volume, intestinal mucosa proliferation/apoptosis, oestrogen receptors (ERs) expression, fatty acid synthase (FAS) and 3-hydroxy-3-methylglutaryl coenzyme A (HMGCoA) reductase gene expression and enzymatic activity. As compared to the standard diet, the salmon oil-enriched diet, containing a high percentage of omega-3 polyunsaturated fatty acids (omega-3 PUFAs) and, to a lesser extent, olive oil-enriched diet reduced polyp number and volume through a reduction of proliferation and a marked proapoptotic effect. These biological effects were mediated by an inhibition of FAS and HMGCoA reductase gene expression and activity and an increase of ERβ/ERα ratio. Our findings suggest that a proper dietary lifestyle could contribute to primary cancer prevention. Summary: Natural substances, components of Mediterranean Diet, may counteract intestinal polyp development through the modulation of metabolic pathways involving lipogenic enzymes and estrogen receptors. Our findings further support the idea that an appropriate dietary treatment is important in colon tumour prevention.