Serotonin helps gut bacteria colonize

Abstract

From the crowded confines of the intestine comes new research about a bacterial species that uses serotonin from the gut to gain an upper hand in its quest to colonize and survive. In studies done in mice, a team of researchers found that Turicibacter sanguinis, a common gut microbe, can signal nearby intestinal cells to release serotonin, a neurotransmitter typically associated with mammalian mood and digestion (Nat. Microbiol. 2019, DOI: 10.1038/s41564-019-0540-4). When the bacteria take up serotonin, the small molecule prompts the expression of genes related to growth and survival, allowing the microbes to colonize the host’s gut, says Elaine Hsiao, the lead researcher on the project at the University of California, Los Angeles. Treating the mice with fluoxetine, sold as Prozac, blocks serotonin uptake and prevents T. sanguinis from colonizing the animals. The Prozac findings may help explain some of the drug’s gastrointestinal side effects, Hsiao says. Mice, human,