title: Effects of dark chocolate on azoxymethane-induced colonic aberrant crypt foci.
abstract: Epidemiologic evidence supports that diets rich in polyphenols promote health and may delay the onset of colon cancer. Cocoa and chocolate products have some of the highest polyphenolic concentrations compared to other polyphenolic food sources. This study tested the hypothesis that a diet including dark chocolate can protect against colon cancer by inhibiting aberrant crypt foci (ACF) formation, downregulating gene expression of inflammatory mediators, and favorably altering cell kinetics. We also investigated whether bloomed dark chocolate retains the antioxidant capacity and protects against colon cancer. Forty-eight rats received either a diet containing control (no chocolate), regular dark chocolate, or bloomed dark chocolate and were injected subcutaneously with saline or azoxymethane. Relative to control, both regular and bloomed dark chocolate diets lowered the total number of ACF (P = 0.022). Chocolate diet-fed animals downregulated transcription levels of COX-2 (P = 0.035) and RelA (P = 0.045). Both chocolate diets lowered the proliferation index (P = 0.001). These results suggest that a diet including dark chocolate can reduce cell proliferation and some gene expression involving inflammation, which may explain the lower number of early preneoplastic lesions. These results provide new insight on polyphenol-rich chocolate foods and colon cancer prevention.
authors.affiliation: School of Exercise and Nutritional Sciences, San Diego State University, San Diego, California 92182-7251, USA. mhong2@mail.sdsu.edu
authors.forename: Mee Young
authors.initials: MY
authors.lastname: Hong
authors.forename: Emily
authors.initials: E
authors.lastname: Nulton
authors.forename: Mahshid
authors.initials: M
authors.lastname: Shelechi
authors.forename: Lisa M
authors.initials: LM
authors.lastname: Hernández
authors.forename: Tricia
authors.initials: T
authors.lastname: Nemoseck
mesh_terms: D058739:Aberrant Crypt Foci / Q000139:chemically induced / Q000517:prevention & control*; D000818:Animals; D000893:Anti-Inflammatory Agents / Q000494:pharmacology; D000975:Antioxidants / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects; D001397:Azoxymethane / Q000633:toxicity*; D002099:Cacao; D002182:Candy; D002273:Carcinogens / Q000633:toxicity; D049109:Cell Proliferation / Q000187:drug effects; D003106:Colon / Q000187:drug effects* / Q000473:pathology; D015179:Colorectal Neoplasms / Q000139:chemically induced / Q000517:prevention & control*; D051546:Cyclooxygenase 2 / Q000235:genetics / Q000378:metabolism; D015536:Down-Regulation; D008297:Male; D010936:Plant Extracts / Q000494:pharmacology; D059808:Polyphenols / Q000494:pharmacology; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D051996:Transcription Factor RelA / Q000235:genetics / Q000378:metabolism
chemical_list: D000893:Anti-Inflammatory Agents; D000975:Antioxidants; D002273:Carcinogens; D010936:Plant Extracts; D059808:Polyphenols; D012333:RNA, Messenger; C498145:Rela protein, rat; D051996:Transcription Factor RelA; D051546:Cyclooxygenase 2; C489691:Ptgs2 protein, rat; D001397:Azoxymethane