Interaction between Intestinal Microbiota and Serotonin Metabolism

Gut microbiota regulates the production of signaling molecules, such as serotonin or 5-Hydroxytryptamine: 5-HT in the host. Serotonin is a biogenic amine that acts as a neurotransmitter in the gut and brain. There is a perfect interaction between human gastrointestinal microbiota and the serotonin system. The gut microbiota plays an important role in the serotonin signaling pathways through the gut-brain axis. It also has a major role in the pathophysiology of serotonin-related metabolic and physiological diseases. The aim of this review was to investigate the relationship between gut microbiota and their role in regulating peripheral serotonin levels. This study could be highly important since there is paucity of information on the relationship between intestinal microbiota and the serotonin system. Numerous studies have shown that changes in the gut microbiota may modulate serotonin signaling system. Also, any disorder in the serotonin system and lack of homeostasis in this system can be effective in the homeostasis shift of intestinal microbiota to dysbiosis and ultimately play a role in causing inflammation in the intestine and gastrointestinal disorders. Evidence on the exact mechanisms of the interaction between intestinal microbiota and serotonin levels indicates a link between intestinal microbiota and this system. Current review showed that gut microbiota could affect the serotonin system through the gut-brain axis. Serotonin signaling in the gut-brain axis could be considered in new therapies to improve serotonin-related disorders. Therefore, further studies are proposed to more accurately determine the association between the gut microbiota and the serotonin system.