Department of Physical Activity Research, National Institutes of Biomedical Innovation, Health and Nutrition (NIBIOHN), Tokyo, 162-8636, Japan.
Department of Clinical Nutrition, National Institutes of Biomedical Innovation, Health and Nutrition (NIBIOHN), Tokyo, 162-8636, Japan.
BMC Microbiol. 2021 Jun 28;21(1):196. doi: 10.1186/s12866-021-02255-6.
Colibactin-producing Escherichia coli containing polyketide synthase (pks E. coli) has been shown to be involved in colorectal cancer (CRC) development through gut microbiota analysis in animal models. Stool status has been associated with potentially adverse gut microbiome profiles from fecal analysis in adults. We examined the association between stool patterns and the prevalence of pks E. coli isolated from microbiota in fecal samples of 224 healthy Japanese individuals.
Stool patterns were determined through factorial analysis using a previously validated questionnaire that included stool frequency, volume, color, shape, and odor. Factor scores were classified into tertiles. The prevalence of pks E. coli was determined by using specific primers for pks E. coli in fecal samples. Plasma and fecal fatty acids were measured via gas chromatography-mass spectrometry. The prevalence of pks E. coli was 26.8%. Three stool patterns identified by factorial analysis accounted for 70.1% of all patterns seen (factor 1: lower frequency, darker color, and harder shape; factor 2: higher volume and softer shape; and factor 3: darker color and stronger odor). Multivariable-adjusted odds ratios (95% confidence intervals) of the prevalence of pks E. coli for the highest versus the lowest third of the factor 1 score was 3.16 (1.38 to 7.24; P for trend = 0.006). This stool pattern exhibited a significant positive correlation with fecal isobutyrate, isovalerate, valerate, and hexanoate but showed a significant negative correlation with plasma eicosenoic acid and α-linoleic acid, as well as fecal propionate and succinate. No other stool patterns were significant.
These results suggest that stool patterns may be useful in the evaluation of the presence of tumorigenic bacteria and fecal fatty acids through self-monitoring of stool status without the requirement for specialist technology or skill. Furthermore, it may provide valuable insight about effective strategies for the early discovery of CRC.
通过动物模型中的肠道微生物组分析，已证实产 colibactin 的大肠杆菌（pks E. coli）与结直肠癌（CRC）的发展有关。粪便分析显示，粪便状态与成人潜在不良的肠道微生物组谱有关。我们检查了 224 名健康日本个体粪便样本中微生物群分离的 pks E. coli 流行率与粪便模式之间的关系。
使用之前验证的问卷通过因子分析确定粪便模式，该问卷包括粪便频率、量、颜色、形状和气味。因子得分分为三分位数。通过粪便样本中 pks E. coli 的特定引物确定 pks E. coli 的流行率。通过气相色谱-质谱法测量血浆和粪便脂肪酸。pks E. coli 的流行率为 26.8%。因子分析确定的三种粪便模式占所有模式的 70.1%（因子 1：频率较低、颜色较深、形状较硬；因子 2：体积较高、形状较软；因子 3：颜色较深、气味较强）。多变量调整后的 pks E. coli 流行率最高与最低三分位组的比值比（95%置信区间）为 3.16（1.38 至 7.24；趋势 P 值=0.006）。这种粪便模式与粪便异丁酸、异戊酸、戊酸和己酸呈显著正相关，但与血浆二十碳烯酸和 α-亚麻酸以及粪便丙酸和琥珀酸呈显著负相关。没有其他粪便模式具有显著相关性。
这些结果表明，通过自我监测粪便状态而无需专门技术或技能，粪便模式可用于评估致癌细菌和粪便脂肪酸的存在，这可能为 CRC 的早期发现提供有价值的见解。
