Tuna Oil Alleviates d‑Galactose Induced Aging in Mice Accompanied by Modulating Gut Microbiota and Brain Protein Expression

To
discern whether tuna oil modulates the expression of brain proteins
and the gut microbiota structure during aging induced by d-galactose, we generated an aging mouse model with d-galactose
treatment, and the mice showed aging and memory deterioration symptoms
according to physiological and biochemical indices. Treatment with
different doses of tuna oil alleviated the symptoms; the high dose
showed a better effect. Subsequently, brain proteomic analysis showed
the differentially expressed proteins were involved in damaged synaptic
system repairment and signal transduction system enhancement. In addition,
tuna oil treatment restored the diversity of gut microbiota, 27 key
operational taxonomic units, which were identified using a redundancy
analysis and were significantly correlated with at least one physiological
index and three proteins or genes. These findings suggest that the
combination of proteomics and gut microbiota is an effective strategy
to gain novel insights regarding the effect of tuna oil treatment
on the microbiota–gut–brain axis.