AUTHOR=Medvedev Alexei , Buneeva Olga 

TITLE=Tryptophan Metabolites as Mediators of Microbiota-Gut-Brain Communication: Focus on Isatin

JOURNAL=Frontiers in Behavioral Neuroscience

VOLUME=16

YEAR=2022

URL=https://www.frontiersin.org/journals/behavioral-neuroscience/articles/10.3389/fnbeh.2022.922274

DOI=10.3389/fnbeh.2022.922274

ISSN=1662-5153

ABSTRACT=<p>Isatin (indole-2,3-dione) is an endogenous regulator, exhibiting various behavioral, biological, and pharmacological activities. Synthesis of isatin includes several crucial stages: cleavage of the tryptophan side chain and subsequent oxidation of the indole nucleus. Although these stages require concerted action of bacterial and host enzymes, there are two pathways of isatin formation: the host and bacterial pathways. Isatin acts as a neuroprotector in different experimental models of neurodegeneration. Its effects are realized <italic>via</italic> up- and downregulation of isatin-responsive genes and <italic>via</italic> interaction with numerous isatin-binding proteins identified in the brain. The effect of isatin on protein-protein interactions in the brain may be important for realization of weak inhibition of multiple receptor targets.</p>