title: Prevention by long-term fermented miso of induction of colonic aberrant crypt foci by azoxymethane in F344 rats.
abstract: The present study was designed to investigate the effects of fermented miso in the diet on the induction of aberrant crypt foci (ACF) by azoxymethane (AOM) in male F344 rats. A total of 50 rats, 8 weeks of age, were divided into 5 groups and given weekly subcutaneous injections of AOM (15 mg/kg body wt) for 3 weeks. Rats were fed a normal control MF solid diet, or solid diet containing 10% long-term fermented (aged), medium- or short-term fermented miso, or 2.2% NaCl for 5 weeks, starting one week before the first AOM dosing. It was found that, compared to the control (MF) diet, the long-term fermented diet significantly decreased (by 22.2%) ACF/colon, but increased (by 18.2%) the number of aberrant crypts (Acs)/focus. The latter was also increased by the medium-term fermented diet (by 25.3%). The PCNA labeling index was only affected by the short-term fermented diet (36.9% increase) and by 2.2% NaCl diet (27.2% increased). The present results indicate that aged or completely fermented miso supplemented into the diet, could act as a chemopreventive agent for colon carcinogenesis.
authors.affiliation: Department of Environment and Mutation, Research Institute for Radiation Biology and Medicine, Hiroshima University, Minami-ku, Hiroshima 734-8553, Japan.
authors.forename: Masayuki
authors.initials: M
authors.lastname: Ohara
authors.forename: Huimei
authors.initials: H
authors.lastname: Lu
authors.forename: Katsutomo
authors.initials: K
authors.lastname: Shiraki
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Ishimura
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Uesaka
authors.forename: Osamu
authors.initials: O
authors.lastname: Katoh
authors.forename: Hiromitsu
authors.initials: H
authors.lastname: Watanabe
mesh_terms: D000818:Animals; D001397:Azoxymethane / Q000633:toxicity; D001835:Body Weight; D002273:Carcinogens / Q000633:toxicity; D003110:Colonic Neoplasms / Q000139:chemically induced / Q000178:diet therapy* / Q000378:metabolism; D004044:Dietary Proteins / Q000008:administration & dosage*; D005285:Fermentation; D007124:Immunoenzyme Techniques; D008297:Male; D009929:Organ Size; D011230:Precancerous Conditions / Q000139:chemically induced / Q000178:diet therapy* / Q000378:metabolism; D018809:Proliferating Cell Nuclear Antigen / Q000378:metabolism; D051381:Rats; D011916:Rats, Inbred F344; D030262:Soybean Proteins / Q000008:administration & dosage*
chemical_list: D002273:Carcinogens; D004044:Dietary Proteins; D018809:Proliferating Cell Nuclear Antigen; D030262:Soybean Proteins; D001397:Azoxymethane