青少年肠道菌群特点分析

Characteristics of intestinal microbiota in adolescents

目的探讨青少年肠道菌群的特点。方法50名12~18岁健康青少年作为青少年组,60岁以下健康人和10岁以下幼儿分别收集50名作为对照组取新鲜粪便,提取DNA在肠道菌群中门和属水平分别选取具有代表性的细菌,进行荧光定量聚合酶链反应（PCR）检测肠道拟杆菌门、厚壁菌门、双歧杆菌、乳杆菌属、肠杆菌、肠球菌及梭菌细菌拷贝数,统计分析各组间差异。结果青少年组拟杆菌门数量明显高于婴幼儿组而低于成年组（P〈0.05）,而青少年组厚壁菌门数量明显低于婴幼儿组而高于成年组（P〈0.05）。青少年组双歧杆菌、乳杆菌数量均明显低于婴幼儿组（P〈0.05）,高于成年组（P〈0.05）;青少年组肠杆菌、肠球菌数量均明显高于幼儿组（P〈0.05）,青少年组和成年组肠杆菌、肠球菌数量组间差异均无统计学意义（P〉0.05）。各组之间梭菌属量差异无统计学意义（P〉0.05）。青少年组双歧杆菌/肠杆菌（B/E）值明显低于婴幼儿组,而高于成年组（P〈0.05）。结论青少年期肠道菌群呈现不同于婴幼儿期及成人期的特点,这种变化可能与饮食改变、机体需求及激素变化有关。

Objective To investigate the characteristics of intestinal microbiota in adolescents.Methods：Fifty adolescents aged 12-18 years old were included in the adolescent group.Fifty healthy subjects under the age of 60 years old and children under 10 years old were included in the control group,respectively.Fresh feces were obtained to extract DNA.Representative bacteria of intestinal microbiota were included,respectively.Fluorescent quantitative PCR was used to measure the bacterial copy number of intestinal Bacteroides,Firmicutes,Bifidobacterium,Lactobacillus,Enterobacteria,Enterococcus and Clostridium.The differences among the groups were analyzed.Results The number of Bacteroides in the adolescent group was significantly higher than that in the infant group,but lower than that in the adult group（P〈0.05）.The number of the Firmicutes in the adolescent group was significantly lower than that in the infant group,but higher than that in the adult group（P〈0.05）.The numbers of Bifidobacterium and Lactobacillus in the adolescent group were significantly lower than those in the infant group（P〈0.05）,but higher than those in the adult group（P〈0.05）.The numbers of Enterobacteriaceae and Enterococcus in the adolescent group were significantly higher than those in the infant group（P〈0.05）.There were no significant differences on the numbers of Enterobacteriaceae and Enterococcus between the adult group and the adolescent group.There was no significant difference on Clostridium among the groups（P〉0.05）.The B/E values（Bifidobacterium/Enterobacteria） in the adolescent group were significantly lower than that in the infant group,but higher than that in the adult group（P〈0.05）.Conclusion As adolescence is a special period of human body,the characteristics of its intestinal microbiota are different from those of infants and adults.The changes may be related to dietary changes,body needs and hormonal changes.