Analysis of gut microbiota diversity in the elderly based on high-throughput sequencing / 中华微生物学和免疫学杂志

ABSTRACT

Objective:To investigate the changes in gut microbiota diversity with age in elderly people using high-throughput sequencing.Methods:Ninety healthy volunteers were recruited. People who were <60 years old (middle-aged group) were set up as a baseline control group (Age A group), while those aged ≥60 years old were further divided into four groups (60-<70: Age B group, 70-<80: Age C group, 80-<90: Age D group, ≥90: Age E group). Fecal samples were collected to extract DNA. The second-generation sequencing technology was used to amplify and sequence the V3-V4 hypervariable region of 16S rDNA. Bioinformatics analysis was performed to compare the differences in gut microbiota and functional genes among groups.Results:At the phylum level, gut microbiota were composed mainly of Firmicute, Bacteroidetes, Proteobacteria and Actinobacteria in different groups. The proportion of Firmicute was the highest, accounting for over 60%, followed by that of Bacteroidetes. At the genus level, the abundance of Faecalibacterium genus decreased with age. The α diversity analysis showed that the gut microbiota in the elderly of different ages had higher abundance and uniformity, and there was no significant difference among groups. However, the β diversity analysis showed that in community structure there was difference between Age A and Age B groups, and similarity between Age B and Age C groups. Conclusions:The community structure of gut microbiota changed significantly between young and middle-aged people and the elderly over 60 years old. It tended to be relatively stable in people of 60-80 years old, but changed again when they were over 80 years old. Chronic inflammatory diseases, metabolic diseases and tumors in the elderly might be associated with the decrease in Faecalibacterium.