It has recently been discovered that the digestive tract is lined with about 100 million nerve cells; the digestive tract has been baptized, metaphorically speaking, as “the second brain,” which contains a multitude of neurotransmitters, viruses, and bacteria that help regulate our emotional state. This second brain, known as the enteric nervous system, is a unique anatomical unit that extends from the esophagus to the anus. Like the nervous system, it produces a whole series of psychoactive substances, such as serotonin, dopamine, and opioids for pain, and synthesizes benzodiazepines. In it, we find the microbiota: a set of microorganisms (viruses and bacteria). Together with the brain, the microbiota directly influences mood, character, or sleep. Knowledge about the possible relationship of the microbiota with frequent neurological diseases is still just beginning. Recently, possible changes in the microbiota have been linked to the onset of Parkinson’s disease (PD). Also, today, we know that there are differences between the microbiota of healthy people and people with multiple sclerosis and that these differences have also been related to the disease and its evolution.
Part of the book: Eat, Learn, Remember
Tryptophan is an essential amino acid. It is metabolized through two main pathways: the kynurenine pathway and the methoxyidol pathway. The intestinal microbiota has been identified as a modifier of the metabolism of tryptophan and its derived metabolites. The resulting metabolites can trigger immune, metabolic, and neuronal effects, at the systemic and distant levels, as well as therapeutic specific and nonspecific targets. The reader reviewing this content will learn the importance of tryptophan biotransformation through metabolism and the host-microbiome complex, the formation of serotonin and kynurenine, the pathways of unwinding and the physiological effects of metabolites within the intestinal part, energy metabolism and neurotransmitters. The effects and pathologies that dysregulation may have with this metabolism will be reviewed, as well as the therapeutic targets and related drugs.
Part of the book: Weight Loss - A Multidisciplinary Perspective [Working title]