【摘要】 目的 研究干酪乳杆菌（Lactobacillus casei,L.casei）对APC^min/+小鼠结直肠腺瘤发生的抑制作用，并且探讨其对肠道菌群的影响。方法 将10只APC^min/+小鼠分为结直肠腺瘤组和L.casei治疗组，结直肠腺瘤组予PBS灌胃作对照，而L.casei治疗组予干酪乳杆菌灌胃，每天记录小鼠体重、毛发、精神状态等一般情况。实验终点分离结肠，测量结肠长度、计算结直肠腺瘤数量，并行HE染色观察结肠病理情况，采集小鼠粪便，利用16s高通量测序分析小鼠粪便菌群的变化。结果 L.casei治疗后APC^min/+小鼠大体状态改善，结肠长度/体重较结直肠腺瘤组显著增加（P<0.01）,结直肠腺瘤数量减少（P>0.05）,组织学癌变倾向更轻；菌群分析提示L.casei治疗后APC^min/+小鼠α-多样性有明显下降趋势（P>0.05）,两组菌群结构差异显著（PC1+PC2=60.58%, Anosim, Amova;P<0.05,P<0.05）,进一步利用LEfSe分析发现L.casei治疗后APC^min/+小鼠Gammaproteobacteria纲、Enterobacteriales目、Enterobacteriaceae科、unidentified＿Enterobacteriaceae属、Faecalibaculum属、Escherichia＿coli种显著增加，而Tenericutes门、Mollicutes纲、Rhizobiales目、Ruminococcaceae科、Eggerthellaceae科、Anaerovorax属、Ileibacterium属、Ileibacterium＿valens种显著减少（P均<0.05）。结论 干酪乳杆菌干预对APC^min/+小鼠结直肠腺瘤有抑制作用，其作用效果可能与下调促癌菌群和上调抑癌共生菌有关。更多还原

【Abstract】 Objective To study the inhibitory effect of colorectal adenoma of Lactobacillus casei（L. casei） on APC^min/+ mice and its effect on gut microbiota. Methods Ten APC^min/+ mice were divided into colorectal adenoma group and L. casei treatment group. The colorectal adenoma group was treated with PBS as control, while the L. casei treatment group was given Lactobacillus casei by gavage. The general conditions of mice including weight, fur change and mental state were recorded every day. The end point of the experiment was to separate the colon, measure the length of the colon, calculate the number of colorectal adenomas, observe the pathology of the colon with HE staining, collect the feces of mice, and analyze the changes of fecal flora of mice with 16 S high-throughput sequencing. Results After L. casei treatment, the general state of APC^min/+ mice was improved, the length/weight of colon were increased significantly（P<0.01）, the number of polyps was decreased（P>0.05）, and the tendency of histological carcinogenesis was lighter. Microbial analysis suggested that the α-diversity of L. casei treated APC^min/+ mice was significantly decreased（P>0.05）, and significant different from model group（PC1+PC2=60.58%, Anosim, AMOVA; P<0.05, P<0.05）. LEfSe analysis showed that Gammaproteobacteria, Enterobacteriales, Enterobacteriaceae, unidentified＿Enterobacteriaceae, Faecalibaculum, and Escherichia coli were increased significantly, while Tenericutes, Mollicutes, Rhizobiales, Ruminococcaceae, Eggerthellaceae, Anaerovorax, Ileibacterium, and Ileibacterium＿valens were decreased significantly（P<0.05）. ConclusionLactobacillus casei has inhibitory effect on the colorectal adenoma of APC^min/+ mice, and its effect may be related to the down-regulation of cancer promoting bacteria and up-regulation of cancer inhibiting symbionts.更多还原