title: Cocoa-rich diet prevents azoxymethane-induced colonic preneoplastic lesions in rats by restraining oxidative stress and cell proliferation and inducing apoptosis.
abstract: Cocoa is a rich source of bioactive compounds with potential chemopreventive ability but up to date its effectiveness in animal models of colon carcinogenesis has not been addressed. Herein, we investigated the in vivo effect of a cocoa-rich diet in the prevention of azoxymethane (AOM)-induced colon cancer and the mechanisms involved. Our results showed that cocoa feeding significantly reduced AOM-induced colonic aberrant crypt foci formation and crypt multiplicity. Oxidative imbalance in colon tissues seems to be prevented by cocoa as indicated by reduced oxidation markers levels and increased enzymatic and non-enzymatic endogenous defences. Cocoa-rich diet also exhibited antiproliferative effects by decreasing the levels of extracellular regulated kinases, protein kinase B and cyclin D1 together with pro-apoptotic effects evidenced by reduced Bcl-x(L)  levels and increased Bax levels and caspase-3 activity. Our findings provide the first in vivo evidence that a cocoa-rich diet may inhibit the early stage of colon carcinogenesis probably by preventing oxidative stress and cell proliferation and by inducing apoptosis.
authors.affiliation: Instituto de Ciencia y Tecnología de Alimentos y Nutrición (ICTAN-CSIC), Madrid, Spain.
authors.forename: Ildefonso
authors.initials: I
authors.lastname: Rodríguez-Ramiro
authors.forename: Sonia
authors.initials: S
authors.lastname: Ramos
authors.forename: Elvira
authors.initials: E
authors.lastname: López-Oliva
authors.forename: Angel
authors.initials: A
authors.lastname: Agis-Torres
authors.forename: Miren
authors.initials: M
authors.lastname: Gómez-Juaristi
authors.forename: Raquel
authors.initials: R
authors.lastname: Mateos
authors.forename: Laura
authors.initials: L
authors.lastname: Bravo
authors.forename: Luis
authors.initials: L
authors.lastname: Goya
authors.forename: María Ángeles
authors.initials: MÁ
authors.lastname: Martín
mesh_terms: D000818:Animals; D016588:Anticarcinogenic Agents / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects*; D001397:Azoxymethane / Q000633:toxicity; D002099:Cacao / Q000737:chemistry*; D053148:Caspase 3 / Q000235:genetics / Q000378:metabolism; D049109:Cell Proliferation / Q000187:drug effects*; D003106:Colon / Q000187:drug effects / Q000473:pathology; D003110:Colonic Neoplasms / Q000139:chemically induced / Q000517:prevention & control*; D019938:Cyclin D1 / Q000235:genetics / Q000378:metabolism; D004032:Diet; D005786:Gene Expression Regulation; D018384:Oxidative Stress / Q000187:drug effects*; D011230:Precancerous Conditions / Q000139:chemically induced / Q000517:prevention & control; D051381:Rats; D051028:bcl-2-Associated X Protein / Q000235:genetics / Q000378:metabolism
chemical_list: D016588:Anticarcinogenic Agents; C494828:Bax protein, rat; C530106:Ccnd1 protein, rat; D051028:bcl-2-Associated X Protein; D019938:Cyclin D1; C505410:Casp3 protein, rat; D053148:Caspase 3; D001397:Azoxymethane