ABSTRACT
Multiple organs are physiologically and pathologically interconnected during aging, and the brain plays a central role in this process. There is a direct two-way communication between the brain and the gut called “brain-gut interaction”, which is of great significance for the study of aging, and the molecular mechanism remains to be further studied. The aim of this study is to explore the mechanism of aging in the context of brain-gut interaction. The results of general physical signs of mice showed that the amount of exercise decreased, body weight and food intake decreased significantly in aged mice (P < 0. 001, P<0. 05). The thymus index of aged mice was significantly lower than that of normal mice (P< 0. 05), and the thymic pathological results showed that the thymic cortex of aging mice was thinner, the boundary between medulla and cortex was blurred, and the cells were loosely arranged. Metabolomics analysis revealed 317 differential metabolites in feces and 100 differential metabolites in hippocampus. The results of microbiome showed that Bacteroidetes and Firmicutes were the dominant phyla of gut microbiota. Bacteroidetes showed an upward trend and Firmicutes showed a downward trend after aging. KEGG pathway results showed that 26 metabolic pathways were related to the study of aging, among which galactose metabolism, ABC transporter and purine metabolism were of great significance for the brain-gut interaction. The results of Spearman correlation analysis of the three groups showed that the types of metabolites involved were mainly lipids and lipid-like molecules and organic acids and derivatives, and the gut microbiota involved were mainly Bacteroidetes and Firmicutes. In conclusion, the present study demonstrated that the synergistic changes between brain and gut in aging mice were related to the mechanism of aging, which provided new insights into the mechanism of aging process.