Chapter 2 Gut–brain communication through microbes

Beyond a local role in intestinal health and homeostasis, the microbial ecosystem that resides in our gut is an essential contributor to proper development, maturation, and function of the central nervous system (CNS). Research to understand the gut–brain axis and the connection between gut microbes and the brain has revealed a substantial role for the gut microbiome in the neurobiology and behavior of the host, including in psychiatric, neurodegenerative, and neurodevelopmental disorders. As research in the field advances, mechanisms mediating this critical aspect of host–microbe communication are being brought to light. This chapter will overview the signaling pathways between gut microbes and the brain. Recent experiments have begun to reveal key neural, immune, and metabolic pathways that contribute to translating an altered microbiome composition into observable phenotypes and behavioral profiles. Moreover, recent advances in translating preclinical observations to clinical cohorts demonstrate the potential for microbiome-targeted therapies in treating CNS disorders.