Linninge Caroline, Ahrné Siv, Molin Göran
Food Hygiene, Department of Food Technology, Engineering and Nutrition, Lund University, Box 124, 221 00, Lund, Sweden,
Antonie Van Leeuwenhoek. 2015 Jan;107(1):149-56. doi: 10.1007/s10482-014-0312-3. Epub 2014 Oct 31.
The composition of the gut microbiota can vary widely between individual mice of the same batch and thereby affect the resulting outcome in experimental studies. Therefore, an efficient method is needed to equalize the gut microbiota prior to the start of critical experiments. In order to minimize variations in gut microbiota between animals and provide the animals with a Gram-negative flora exposing lipopolysaccharides in the cell-walls, C57BL/6 mice were given a mixture of ampicillin, metronidazole and clindamycin in the drinking water for 3 days and then Escherichia coli for two additional days. Treatment with antibiotics alone or with antibiotics in combination with E. coli was well tolerated by all animals. Body weight and liver weight were not affected, although higher hepatic fat content was found in treated animals (p < 0.05). The diversity of the gut microbiota was strongly reduced in animals treated with antibiotics and antibiotics in combination with E. coli (p < 0.01), without affecting the total amount of bacteria. Cloned and sequenced 16S rRNA genes showed high presence of Enterobacteriaceae and Porphymonadaceae in the treated animals. Analysis with Principal Component Analysis gave a clear separation of the composition in microbiota between different treatment groups. The described treatment efficiently equalized the gut microbiota and provided the animals with a strong abundance of Enterobacteriaceae without changing the total load of bacteria. This is a straightforward, lenient and efficient method of pre-treatment to equalize the gut microbiota of mice as a starting procedure of animal studies.
同一批次的个体小鼠之间，肠道微生物群的组成可能存在很大差异，从而影响实验研究的最终结果。因此，需要一种有效的方法在关键实验开始前使肠道微生物群均衡化。为了尽量减少动物之间肠道微生物群的差异，并为动物提供一种细胞壁中暴露脂多糖的革兰氏阴性菌群，给C57BL/6小鼠在饮用水中添加氨苄青霉素、甲硝唑和克林霉素的混合物，持续3天，然后再额外添加大肠杆菌，持续2天。单独使用抗生素或抗生素与大肠杆菌联合使用的处理方式，所有动物都能很好地耐受。体重和肝脏重量未受影响，尽管在接受处理的动物中发现肝脏脂肪含量较高（p < 0.05）。用抗生素以及抗生素与大肠杆菌联合处理的动物，其肠道微生物群的多样性大幅降低（p < 0.01），但不影响细菌总量。对克隆和测序的16S rRNA基因分析显示，处理过的动物中肠杆菌科和卟啉单胞菌科大量存在。主成分分析表明，不同处理组的微生物群组成有明显区分。所描述的处理方法有效地均衡了肠道微生物群，并使动物体内肠杆菌科大量富集，同时不改变细菌的总载量。这是一种简单、宽松且高效的预处理方法，可作为动物研究的起始步骤来均衡小鼠的肠道微生物群。
