基于高通量测序技术研究老年人肠道菌群结构变化

Changes of Gut Microbiota Composition in Elderly People Based on High-throughput Sequencing

背景:随着我国人口的老龄化,老年人的健康保健备受关注。目的:探讨增龄对肠道菌群结构的影响,以期通过调节肠道微生态提升老年人健康水平。方法:收集30例健康老年人(60~80岁)和10例健康青年人(18~40岁)的粪便样本,采用高通量测序技术测定所有粪便细菌的16S rRNA基因V3、V4区序列,使用MiSeq 16S宏基因组APP和Qimme软件分析菌群物种分类、物种多样性指数、样本组间显著性差异和各组生物学标志物。结果:老年健康组与青年健康组肠道菌群OTU均数接近,物种多样性相似(P>0.05)。Metastats分析显示,在菌门水平上,两组间优势菌门拟杆菌门(Bacteroidetes)、厚壁菌门(Firmicutes)和变形菌门(Proteobacteria)差异均无统计学意义(P>0.05)。在菌属水平上,两组间共有20余种菌属差异有统计学意义(P<0.05)。老年健康组八叠球菌属(Sarcina)、厌氧支原体属(Anaeroplasma)、甲基杆菌属(Methylobacterium)、丛毛单胞菌属(Comamonas)、Olsenella、Rheinheimera、Terrisporobacter、食酸菌属(Acidovorax)、红蝽菌科(Coriobacteriaceae_UCG-003)、粪芽孢菌属(Coprobacillus)、Gelria、Aquabacterium、氨基酸球菌属(Acidaminococcus)、Caldicoprobacter、肠杆菌属(Enterorhabdus)、Turicibacter丰度显著增高,青年健康组厌氧乙酸属(Acetanaerobacterium)、漫游球菌属(Vagococcus)、瘤胃菌科(Ruminococcaceae_UCG-009)、草酸杆菌属(Oxalobacter)、粪球菌属_2(Coprococcus_2)丰度显著增高。LEfSe分析显示,老年健康组生物学标志物富集于食酸菌属、缠结优杆菌(Eubacterium_nodatum_group)、梭菌科_1(Clostridiaceae_1)、丛毛单胞菌科(Comamonadaceae),青年健康组则富集于普氏菌属_2(Prevotella_2)、罗氏菌属(Roseburia)、厌氧乙酸属。结论:随着年龄的增长,肠道菌群结构和功能发生一定程度的改变。老年人产丁酸盐细菌明显减少,同时机会致病菌增多。

Background:With the trend of aging of Chinese population, the healthcare of the elderly has attracted much attention. Aims: To study the impact of aging on gut microbiota composition for the sake of achieving health promotion in the elderly via regulation of gut microbiota. Methods: Thirty healthy elderly subjects ( 60-80 years) and 10 healthy young subjects (18-40 years) were enrolled and the fecal samples were collected. High-throughput sequencing was performed for determining the sequence of 16S rRNA gene V3-V4 region of all fecal bacteria. Then MiSeq 16S metagenomic APP and Qimme software were used to analyze the classification and diversity index of gut microbiota, the significant differences between sample groups and the biomarkers for each group. Results: The mean OTU and diversity of gut microbiota between healthy elderly group and healthy young group were similar (P>0.05). Metastats analysis showed that there were no significant differences between the two groups in dominant phyla, including Bacteroidetes, Firmicutes and Proteobacteria 0.05). At the genus level, more than 20 genera had statistically significant differences between the two groups The abundance of Sarcina, Anaeroplasma, Methylobacterium, Comamonas, Olsenella, Rheinheimera, Terrisporobacter, Acidovorax, Coriobacteriaceae_UCG-003, Coprobacillus, Gelria, Aquabacterium, Acidaminococcus, Caldicoprobacter, Enterorhabdus and Turicibacter were significantly increased in healthy elderly group, while the abundance of Acetanaerobacterium, Vagococcus, Ruminococcaceae_UCG-009, Oxalobacter and Coprococcus_2 were significantly increased in healthy young group. LEfSe analysis showed that the biomarkers of healthy elderly group were enriched in Acidovorax, Eubacterium_nodatum_group, Clostridiaceae_1 and Comamonadaceae, and those of the healthy young group were concentrated in Prevotella_2, Roseburia and Acetanaerobacterium. Conclusions: The composition and function of gut microbiota change with aging to some extent. Butyrate-producing bacteria are significantly reduced whereas the opportunistic pathogens are increased in the elderly.