Institute of Fermentation Technology and Microbiology, Technical University of Lodz, Department of Biotechnology and Food Science, Wolczanska 171/173, 90-924 Lodz, Poland.
Environ Toxicol Pharmacol. 2012 Nov;34(3):895-904. doi: 10.1016/j.etap.2012.08.009. Epub 2012 Sep 2.
The aim of the study was to investigate the effects of beetroot juice fermented by Lactobacillus brevis 0944 and Lactobacillus paracasei 0920 (FBJ) on carcinogen induction of aberrant crypt foci (ACF) in rat colon. 2-Amino-1-methyl-6-phenylimidazo[4,5-b] pyridine (PhIP) was used as carcinogen, which was administrated intragastrically at a dose of 10 μg/day, every day of the experiment. Additionally, we investigated the cytotoxicity and genotoxicity of fecal water from experimental animals in the Caco-2 cell line, evaluated by MTT test and the comet assay, respectively, as well as by the count of bacteria adhered to colon epithelium assessed by fluorescence in situ hybridization. Oxidative stress in rats was expressed by measuring serum antioxidant status and the level of malondialdehyde in the kidneys and liver. The experimental rats were divided into four groups based on diet type: basal diet, basal diet supplemented with FBJ, basal diet and PhIP treatment, and basal diet supplemented with FBJ and PhIP treatment. FBJ significantly reduced the number of ACF in PhIP-treated rats (from 59 ± 18 to 26 ± 4). Moreover, the number of extensive aberrations (more than 4 crypts in a focus) decreased from 52 ± 18 to 18 ± 4. Fecal water obtained from rats fed with a PhIP-containing diet induced pronounced cytotoxic and genotoxic effects in Caco-2 cells, but FBJ supplementation of the diet abolished these effects. In groups fed dietary PhP and FBJ the latter was found to increase the antioxidant status of serum from 40% to 66% depending on the fraction. Reduced concentration of malondialdehyde was found only in the kidneys of rats fed with PhIP and FBJ. FBJ present in the diet of rats causes a reduction of MDA in the kidneys from 118.7 nmol/g tissue to 100 nmol/g tissue. The presence of FBJ in the diet of rats significantly increased the count of bacteria, including Lactobacillus/Enterococcus and Bacteroides-Prevotella group adhered to colonic epithelium. In conclusion, supplementation of the diet with lactofermented beetroot juice may provide protection against precancerous aberrant crypt formation and reduce the cytotoxic and genotoxic effects of fecal water and improve the oxidative status of the organism.
本研究旨在探讨红甜菜汁经短乳杆菌 0944 和副干酪乳杆菌 0920（FBJ）发酵后对大鼠结肠致瘤诱导的异常隐窝病灶（ACF）的影响。2-氨基-1-甲基-6-苯基咪唑[4,5-b]吡啶（PhIP）被用作致癌剂，以 10μg/天的剂量每天经胃内给药。此外，我们通过 MTT 试验和彗星试验分别评估了实验动物粪便水对 Caco-2 细胞的细胞毒性和遗传毒性，通过荧光原位杂交评估了粪便水对结肠上皮附着细菌的计数。通过测量血清抗氧化状态和肾脏、肝脏中丙二醛的水平来评估大鼠的氧化应激。实验大鼠根据饮食类型分为四组：基础饮食、基础饮食加 FBJ、基础饮食加 PhIP 处理和基础饮食加 FBJ 和 PhIP 处理。FBJ 显著减少了 PhIP 处理大鼠的 ACF 数量（从 59±18 个减少到 26±4 个）。此外，广泛的畸变（一个病灶中超过 4 个隐窝）的数量从 52±18 个减少到 18±4 个。用含有 PhIP 的饮食喂养的大鼠的粪便水在 Caco-2 细胞中引起明显的细胞毒性和遗传毒性作用，但 FBJ 补充饮食可消除这些作用。在喂食含 PhP 和 FBJ 的饮食的大鼠中，FBJ 增加了血清抗氧化状态，依分组不同，增加了 40%至 66%。仅在喂食 PhIP 和 FBJ 的大鼠的肾脏中发现丙二醛浓度降低。FBJ 存在于大鼠饮食中，使肾脏中的 MDA 从 118.7 nmol/g 组织减少到 100 nmol/g 组织。FBJ 存在于大鼠饮食中，显著增加了粘附在结肠上皮的细菌计数，包括乳杆菌/肠球菌和拟杆菌-普雷沃氏菌组。总之，饮食中添加乳铁蛋白发酵的甜菜汁可能提供对癌前异常隐窝形成的保护，并减少粪便水的细胞毒性和遗传毒性作用，改善机体的氧化状态。
