Comparison of gene expressions between LB81 yogurt-intake mice and control mice in the intestine, liver and spleen at 28 months of age

We performed the long-term administration experiment using a yogurt fermented with Lactobacillus delbrueckii subsp. bulgaricus 2038 and Streptococcus thermophilus 1131 (LB81 yogurt) for 20 months in order to understand the effects of the long-term intake of probiotics on mice. Microarrays were used to compare the gene expressions of the intestine, liver and spleen tissues between control mice and LB81 yogurt-intake mice at 28 months of age. Abbreviations used: A, LB81 yogurt-intake mice; C, control mice The eight-month-old ICR male mice obtained from Japan SLC (Hamamatsu, Shizuoka, Japan) were fed on a normal diet (AIN-93) (Oriental Yeast, Tokyo) or the same diet containing 1–2% LB81 yogurt until they were 28 months of age. We isolated the jejunum, ileum, distal colon, liver and spleen tissues from the control mice (n=9) and the LB81 yogurt-intake mice (n=10) at 28 months of age. Equal amounts of total RNA, previously extracted from the tissues of each mouse, were pooled and mixed for each group. The RNA mixtures (100 ng) were individually amplified using the GeneChip 3’IVT Express kit and then hybridized to an Affymetrix Mouse Genome 430 2.0 chip (GPL1261; 45,101 probes).

本研究开展了为期20个月的长期饲喂实验，以德氏乳杆菌保加利亚亚种2038（Lactobacillus delbrueckii subsp. bulgaricus 2038）与嗜热链球菌1131（Streptococcus thermophilus 1131）发酵制备的LB81酸奶为受试制剂，旨在探究益生菌长期摄入对小鼠的影响。于小鼠28月龄时，采用基因芯片（microarrays）技术对比对照组与LB81酸奶摄入组小鼠的肠道、肝脏及脾脏组织的基因表达水平。本研究所用缩写定义如下：A代表LB81酸奶摄入组小鼠，C代表对照组小鼠。本研究使用的实验动物为8月龄雄性ICR小鼠，购自日本静冈县滨松市的日本SLC（Japan SLC）公司。实验期间，小鼠分为两组，分别饲喂正常AIN-93饲料（日本东京Oriental Yeast公司生产），或在同款基础饲料中添加1%~2%的LB81酸奶，持续饲喂至小鼠生长至28月龄。在小鼠28月龄时，分别从对照组（n=9）与LB81酸奶摄入组（n=10）小鼠体内分离空肠、回肠、远端结肠、肝脏及脾脏组织。提取每只小鼠组织中的总RNA，取等量总RNA按实验组与对照组分别混合富集。取100 ng的各组RNA混合样本，分别采用GeneChip 3’IVT Express试剂盒进行体外转录扩增，随后将扩增产物与Affymetrix小鼠基因组430 2.0芯片（GPL1261，包含45101个探针）进行杂交反应。