Fig. 2.

Gut microbiota and brain function in Italian centenarians. This figure summarizes our studies on the phenotypic characteristics of Italian centenarians. In extreme longevity complex remodeling of the GM is reflected at a systemic level by specific signatures of blood and urine markers (inflammatory, lipidic and metabolic). The strong two-way connection between GM and brain is likely to positively affect the well-preserved cognitive function of centenarians until a very advanced age. The fundamental role in the effect on the brain by bacterial tryptophan metabolism via the serotonin and/or kynurenine pathways deserves to be further investigated. AD Alzheimer’s disease, PD Parkinson’s disease, SCFAs short-chain fatty acids, IL-6 interleukin-6, IL-8 interleukin-8, 9-HODE 9-hydroxy-octadecadienoic acid, 9-oxo-HODE 9-oxo-octadecadienoic acid, PCS p-cresol sulfate, PAG phenylacetylglutamine