The US Department of Agriculture’s MyPyramid guidelines introduced a near doubling of the dietary recommendations for vegetables including dry beans—an important food staple in many traditional diets that can improve public health and nutrition. Populations with high legume (peas, beans, lentils) consumption have a low risk of cancer and chronic degenerative diseases. Common beans (Phaseolus vulgaris L.) are known as a rich, reliable source of non-digested compounds like fiber, phenolics, peptides and phytochemicals that are associated with health benefits. Emerging evidence indicates that common bean consumption is associated with reduced cancer risk in human populations, inhibiting carcinogenesis in animal models and inducing cell cycle arrest and apoptosis in cell cultures. Fiber may reduce the risk of premature death from all causes, whereas the whole non-digestible fraction from common beans exhibits anti-proliferative activity and induces apoptosis in vitro and in vivo colon cancer. The mechanisms responsible for this apparently protective role may include gene-nutrient interactions and modulation of proteins’ expression. This review investigates the potential health benefits and bioactivity of beans on tumor inhibition, highlighting studies involving functional compounds, mainly non-digestible fractions that modulate genes and proteins, thereby, unraveling their preventive role against the development of cancer.
The non-digestible fraction (NDF) of common bean (Phaseolus vulgaris L.) cultivar Bayo Madero was evaluated for its chemopreventive effect on azoxymethane (AOM) induced aberrant crypt foci (ACF) in rats. Diets containing cooked beans (CB) or its non-digestible fraction (NDF) were fed to 72 male rats after 2 azoxymethane injections (15 mg kg−1 of body weight once a week for 2 weeks). ACF number, short chain fatty acids (SCFA) and β-glucuronidase activity were measured in colon sections from rats sacrificed 7 weeks after the last AOM injection. Food intake and weight gain of rats were unaffected by CB and NDF. CB and NDF suppressed the AOM-induced formation of ACF (0.8 and 1.5 ACF/distal zone, respectively vs. 6.6 ACF/distal zone based on methylene blue stain) and lowered β-glucuronidase activity in cecal, colonic and fecal content compared to AOM group. SCFA production was not significantly different among fecal, cecal and colonic content. These results indicate that CB and NDF from Bayo Madero provide direct chemoprotection against early stage of azoxymethane (AOM)-induced colon cancer in rats.
1 March 2016 in Journal of Colloid and Interface Science
Bisphenol A (BPA) promotes colon cancer by altering the physiological functions of hormones. Quercetin (Q) can regulate signaling pathways through hormone receptors, inhibiting cancer cells. The antiproliferative effects of Q and its fermented extract (FEQ, obtained by Q gastrointestinal digestion and in vitro colonic fermentation) were analyzed in HT-29 cells exposed to BPA. Polyphenols were quantified in FEQ by HPLC and their antioxidant capacity by DPPH and ORAC. Q and 3,4-dihydroxyphenylacetic acid (DOPAC) were quantified in FEQ. Q and FEQ exhibited antioxidant capacity. Cell viability with Q+BPA and FEQ+BPA was 60% and 50%, respectively; less than 20% of dead cells were associated with the necrosis process (LDH). Treatments with Q and Q+BPA induced cell cycle arrest in the G0/G1 phase, and FEQ and FEQ+BPA in the S phase. Compared with other treatments, Q positively modulated ESR2 and GPR30 genes. Using a gene microarray of the p53 pathway, Q, Q+BPA, FEQ and FEQ+BPA positively modulated genes involved in apoptosis and cell cycle arrest; bisphenol inhibited the expression of pro-apoptotic and cell cycle repressor genes. In silico analyses demonstrated the binding affinity of Q > BPA > DOPAC molecules for ERα and ERβ. Further studies are needed to understand the role of disruptors in colon cancer.