高脂饮食中添加短链菊粉对小鼠肠道菌群的影响

Effect of Short-chain Inulin Supplement on the Gut Microbiota in Mice Fed by High Fat Diet

目的:探究高脂饮食中添加短链菊粉对小鼠肠道菌群的影响。方法:选择8周龄雄性小鼠,5只喂食高脂饲料,5只喂食10%菊粉复合型高脂饲料,喂食8周后收集小鼠粪便,检测小鼠粪便中三种主要的短链脂肪酸。同时,提取小鼠粪便中的细菌基因组,对菌群基因组16S rRNA基因V4高变区进行测序,对数据进行PCoA分析、Alpha多样性分析、LEfSe分析和16S功能预测。结果:菊粉添加后,小鼠粪便中含有的细菌DNA量增多,短链脂肪酸增加。菊粉组和对照组PCoA图可以看到明显聚类。菊粉组物种多样性低于对照组。菊粉组小鼠粪便中S24_7菌科丰度上升;Lachnospiraceae(毛螺菌科),Ruminococcaceae(瘤胃菌科)和Deferribacteraceae(脱铁杆菌科)丰度下降。16S基因功能预测发现22个第二层级的KEGG通路发生变化。结论:高脂饮食情况下短链菊粉的添加会改变小鼠肠道菌群,继而影响肠道菌群的功能。

ABSTRACT Objective： Detect the gut microbiota change in mice caused by 10 % short-chain inulin addition in high fat diet condition. Methods： 8-week-old male C57/B6J mice, 5 mice were fed with high fat diets, 5 mice were fed with high fat diets with 10 % short-chain inulin addition. Fed 8 weeks and then collected fresh feces. Detected the three main short chain fatty acids in fresh feces. Extracted gut bacteria genome DNA for 16S rRNA V4 region sequencing. Principal Coordinate Analysis （PCoA）, Alpha diversity and LEfSe analysis were performed to detect gut microbiota changes induced by short chain inulin. Results： Gut bacterial DNA amount and SCFAs amount per gram feces increased. PCoA analysis demonstrated fecal microbiota from inulin and control group mice had distinctive different features and clustered well. Inulin group owned lower fecal microbiota diversity compared with control group. LEfSe analysis revealed that in family level, S24_7 increased, Deferdbacteraceae, Laclmospiraceae and Ruminococcaceae decreased. PICRUSt predicted that 22 level 2 KEGG Orthology groups changed. Conclusions： Inulin addition altered the gut microbiota composition in mice in high fat diet condition and impact the gut microbiota gene function.