Recently gut bacterial populations seem to be involved in many functions and in the pathogenesis
of several medical conditions. Traditionally the intestinal microbiome has been recognized to
play an important role in metabolizing food compounds in simpler chemical structures for the absorption
of different nutrients, and in maintenance control of gastrointestinal pathogens species. Bacterial populations
are implicated in a complicated network of interactions within the immune system, epithelial cells
local endocrine system, that affects the peripheral and the central nervous system, via blood circulation.
Microbiome influencing the mind via immune, endocrine and metabolic signalling, is able to exert some
clinical effects in different mental diseases. It releases endocrine substances through several pathways
involved in the modulation of neuroinflammation and production of several neurotrasmitter precursors.
It has recently been named psychobiome. It is known that phenolic compounds are able to influence microbiome
proliferation and to exert several roles, especially regarding neuroinflammation in depressive
and anxious behaviour. The clinical effects are reported in the literature. The aim of this study is to highlight
the interaction between polyphenols and microbiota- gut-brain axis.