Although the vast majority of research on serotonin has centered on its effects in the brain, about 90 percent of this neurotransmitter – a chemical that nerve cells use to communicate with each other – is produced in the gastrointestinal tract, explains study leader Vanessa Sperandio, Ph.D., a professor of microbiology and biochemistry at UT Southwestern Medical Center.
Because gut bacteria are significantly affected by their environment, Sperandio, along with UTSW doctoral student Aman Kumar, laboratory manager Regan Russell, and their colleagues, wondered whether the serotonin produced in the gut can affect the virulence of pathogenic bacteria that infect the gastrointestinal tract.
Using mice, the researchers studied how serotonin might change the ability for Citrobacter rodentium – a mouse gut bacterium often used as an analog for E. coli in humans – to infect and sicken their hosts.
Because many species of gut bacteria also have CpxA, it’s possible that serotonin could have wide-ranging effects on gut bacterial health, Sperandio says.
In the future, she adds, she and her colleagues plan to study the feasibility of manipulating serotonin levels as a way of fighting bacterial infections in the gastrointestinal tract.
