Aging progression of human gut microbiota

Abstract

BackgroundHuman gut microbiota are important for human health and have been regarded as a “forgotten organ”, whose variation is closely linked with various factors, such as host genetics, diet, pathological conditions and external environment. The diversity of human gut microbiota has been correlated with aging, which was characterized by different abundance of bacteria in various age groups. In the literature, most of the previous studies of age-related gut microbiota changes focused on individual species in the gut community with supervised methods. Here, we aimed to examine the underlying aging progression of the human gut microbial community from an unsupervised perspective.ResultsWe obtained raw 16S rRNA sequencing data of subjects ranging from newborns to centenarians from a previous study, and summarized the data into a relative abundance matrix of genera in all the samples. Without using the age information of samples, we applied an unsupervised algorithm to recapitulate the underlying aging progression of microbial community from hosts in different age groups and identify genera associated to this progression. Literature review of these identified genera indicated that for individuals with advanced ages, some beneficial genera are lost while some genera related with inflammation and cancer increase.ConclusionsThe multivariate unsupervised analysis here revealed the existence of a continuous aging progression of human gut microbiota along with the host aging process. The identified genera associated to this aging process are meaningful for designing probiotics to maintain the gut microbiota to resemble a young age, which hopefully will lead to positive impact on human health, especially for individuals in advanced age groups.

Gut microbiota: effect of pubertal status

“…Recent studies have yielded insight into the intricate interactions between age and the gut microbiota by 16S rRNA sequencing [ 10 ]. With increasing age, it has been observed a gradual and steady reduction in the population of aerobes and facultative anaerobes, in concert with a simultaneous upsurge in the number of anaerobes [ 5 , 11 ].…”

Gut Microbiota: Effect of Pubertal Status

“…Recent studies exploring bacterial 16S rDNA genes have yielded insight into the intricate interactions between age and the gut microbiota (13). With increasing age, there is a gradual and steady reduction in the population of aerobes and facultative anaerobes, in concert with a simultaneous upsurge in the number of anaerobes (5,14).…”

“…However, although healthy pre-adolescent children (ages 7-12 years) and adults harbored similar numbers of taxa and functional genes, their relative composition differed signi cantly (4). Nonetheless, a large scale study by Enck et al using conventional colony plating to assess numbers of several bacterial genera, found no noticeable changes in children between [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18] years old, including stable levels of Bi dobacterium and Lactobacillus (5). Recently, with the expansion and availability of bacterial DNA sequencing technology, a study revealed that comparison of distal intestinal microbiota composition between adolescents (11-18 years of age) and adults, a statistically signi cant higher abundance of the genera Bi dobacterium and Clostridium was found in adolescent samples.…”

Gut Microbiota: Effect of Pubertal Status

“…Recent studies have yielded insight into the intricate interactions between age and the gut microbiota by 16S rDNA sequencing (13). With increasing age, it has been observed a gradual and steady reduction in the population of aerobes and facultative anaerobes, in concert with a simultaneous upsurge in the number of anaerobes (5,14).…”