Masaoka Y, Watanabe H, Katoh O, Ito A, Dohi K
Department of Environment and Mutation, Hiroshima University, Japan.
Nutr Cancer. 1998;32(1):25-8. doi: 10.1080/01635589809514712.
The present study was designed to investigate the effects of dietary miso and NaCl supplementation on the development of aberrant crypt foci (ACF) induced by azoxymethane (AOM) in male F344 rats. A total of 76 rats, six weeks of age, were divided into seven groups and given weekly subcutaneous injections of AOM (15 mg/kg body wt) for three weeks to induce ACF. The animals were placed on diets one week before the first AOM dosing. Group 1 was fed a normal diet as a control. Groups 2-4 were fed diets containing 5%, 10%, and 20% miso, respectively, and Groups 5 and 6 were fed diets containing 2.2% and 4.4% NaCl, respectively, for five weeks. Group 7 was fed a normal diet without carcinogen exposure. Dietary miso inhibited the development of ACF in a dose-dependent manner (y = -3.9x + 140, r = -0.94). Thus the mean numbers of ACF per colon were significantly lower in Groups 3 and 4 than in Group 1 (p < 0.01), and there were fewer aberrant crypts per colon in Group 4 than in Group 1. NaCl supplementation was associated with fewer ACF, but this was not statistically significant. 5-Bromo-2'-deoxyuridine labeling indexes in the colonic epithelium were significantly lower in Group 3 than in Group 1 (p < 0.05). The present results indicate that dietary miso could act as a chemopreventive agent for colon carcinogenesis.
本研究旨在探讨膳食中添加味噌和氯化钠对雄性F344大鼠由氧化偶氮甲烷（AOM）诱导产生的异常隐窝灶（ACF）发育的影响。总共76只六周龄大鼠被分为七组，连续三周每周皮下注射AOM（15毫克/千克体重）以诱导ACF。在首次注射AOM前一周，将动物置于相应饮食中。第1组喂食正常饮食作为对照。第2 - 4组分别喂食含5%、10%和20%味噌的饮食，第5和6组分别喂食含2.2%和4.4%氯化钠的饮食，持续五周。第7组喂食正常饮食且不接触致癌物。膳食味噌以剂量依赖方式抑制ACF的发育（y = -3.9x + 140，r = -0.94）。因此，第3组和第4组每结肠ACF的平均数量显著低于第1组（p < 0.01），且第4组每结肠的异常隐窝比第1组少。补充氯化钠与较少的ACF相关，但无统计学意义。第3组结肠上皮中的5 - 溴 - 2'-脱氧尿苷标记指数显著低于第1组（p < 0.05）。目前的结果表明，膳食味噌可作为结肠癌发生的化学预防剂。
