Comprehensive 16S rRNA sequencing based microbiomes and 1H NMR based metabolomics reveal the relationships of aging and constipation.

Aging is a complex physiological process associated with degenerative disorders of metabolism and intestinal flora. Constipation is an age-dependent gastrointestinal disease, which is involved in several diseases, such as cardiovascular and cerebrovascular diseases, colon cancer, etc. Gut microbiota is involved in both aging and constipation, which is probably through metabolism. Yet, the underlying mechanisms are still unclear. Our findings showed significant changes in the cecum microbiome compositions across aging and constipation, and the community composition is similar in both. A cluster analysis demonstrated that the key gut bacteria associated with aging and the key gut bacteria associated with constipation were clustered together. Function analysis explored the associations between both via specific gut bacteria's metabolism pathways, involving in 8 metabolic pathways. Associated networks showed that not only gut microbial metabolites are important signaling molecules associated with aging and constipation, but also the occurrence and the development of senescence and constipation are affected at multiple levels and by multiple factors. In this study, both macro and micro indexes, and traditional and modern indexes are combined to prove the important regulatory roles of intestinal microorganisms in aging and constipation, and systematically elaborated the fact that constipation and aging are mutual causation and mutual influences.