UNESP São Paulo State University, Department of Food and Nutrition, Araraquara Rodovia Araraquara/Jau Km 1,14801-902, Araraquara, SP, Brazil.
J Int Soc Sports Nutr. 2009 Aug 6;6:17. doi: 10.1186/1550-2783-6-17.
In this study the influence of moderate or intense physical exercise, alone or in combination with the consumption of a soya product fermented with Enterococcus faecium, on the development of colon cancer induced chemically in rats with 1,2-dimethylhydrazine (DMH), was investigated.
Eighty male Wistar SPF rats were randomly allocated to 8 groups (n = 10). One week after the start of the program of product ingestion and/or physical activity, all animals except the controls (group I) were injected subcutaneously with 50 mg/kg b.w. of 1,2-dimethylhydrazine (DMH). This procedure was repeated at the end of the second week. At the end of the 6-week experiment, all the animals were euthanized; the colons were removed and numbers of ACF was estimated.
Twenty-four days after the induction of pre-neoplastic lesions, it was evident that the formation of ACF was not significantly reduced by the ingestion of the fermented product, by intense or moderate physical activity or by a combination of these factors, in comparison with the positive control group of rats (p < 0.05). On the other hand, the performance of intense exercise, on its own, increased the number of ACF.
The results reported in this article show that consumption of the fermented soy product described here and the practice of physical exercise (intense or moderate) were incapable, separately or combined, of inhibiting the formation of ACF in DMH-induced rats. The intense physical exercise led to an increased number of foci in the colons of these rats and, probably, to greater susceptibility to colorectal cancer.
本研究旨在探讨中等或剧烈强度的身体锻炼，单独或与食用富含屎肠球菌发酵大豆产品相结合，对用 1,2-二甲基肼（DMH）诱导的大鼠结肠癌发展的影响。
将 80 只雄性 Wistar SPF 大鼠随机分为 8 组（n = 10）。在开始摄入产品和/或进行身体活动的一周后，除对照组（I 组）外，所有动物均接受皮下注射 50mg/kg b.w.的 1,2-二甲基肼（DMH）。第二周结束时重复此程序。在 6 周实验结束时，所有动物均被安乐死；取出结肠并估计 ACF 的数量。
在诱导前瘤病变 24 天后，与阳性对照组大鼠相比，摄入发酵产品、进行剧烈或中等强度的身体活动或这些因素的组合，均不能显著减少 ACF 的形成（p<0.05）。另一方面，单独进行剧烈运动增加了 ACF 的数量。
本文报道的结果表明，单独或联合使用本文所述发酵大豆产品和进行身体锻炼（剧烈或中等强度），均不能抑制 DMH 诱导的大鼠中 ACF 的形成。剧烈的身体锻炼导致这些大鼠结肠中焦点数量增加，可能使它们更容易患上结直肠癌。
