Unexpected questions appear in science. If we asked the inhabitant where to find a second brain, very few would think to look for it in the intestines. However, the gastrointestinal system has two hundred million neurons: more than the brain of a dog or the entire spinal cord. That is, such a number of neurons must, undoubtedly, have a specific function. This cerebroenteric system is mainly associated with the vagus nerve, but, nevertheless, it works completely independently of the central nervous system.
That is, although it is known that there has been a joint operation for a long time (where, for example, psychological problems affect the intestines in a stressful situation, such as an examination or danger), at present the importance of the relationship between the brain and the enteric is important. , that is, the intestine through millions of neurons, its neurotransmitters and microbes contained in it can modify the brain.
Thus, there is a return path from the main compound, which is the vagus nerve, a long structure of interaction between the intestine and the brain. But it also establishes a connection with the spinal cord of the central nervous system, with the entire local autonomic system, which unconsciously regulates the balance of the body and the work of the intestines. A regulator that connects the spinal cord (with vegetative medullary neurons) with a system of neurons in the gastrointestinal wall, in a diffuse form.
An important number of neurons possessed by the gastrointestinal system regulates intestinal movements, which have a special rhythmic and consistent activity. It also regulates digestion, secretion of digestive substances and enzymes. It also synthesizes neurotransmitters, some of which are first found in the intestines, such as neuropeptides. Human intestinal cells produce 90 percent of the important neurotransmitter serotonin of the entire human body. This substance is fundamental in the functioning of various physiological processes, including state of mind, anxiety and pain in the central nervous system. Its reduction causes an affective state, and also reduces physiological anxiety, a necessary function for normal human behavior. However, at the intestinal level, serotonin generates a synchronous regulation of the movement of the intestine (peristalsis).
Communication of the nervous system of the intestine with the brain, apparently, is associated with various diseases. Among them are depression, anxiety, obesity and irritable bowel. There are causal hypotheses about even more serious problems, such as neurodegenerative diseases (Parkinson’s disease), autism and schizophrenia; assumptions that are not related to contradictions.
This system is further complicated if one considers that a particularly large intestine or large intestine supports in its space the specific intestinal flora necessary not only for proper digestion, but also for the proper functioning of the intestinal nervous system. In the intestines hundreds of billions of microorganisms (microbiome). This place is very special and different from the usual. Currently, it is mostly anaerobic, which means that it contains organisms that do not use oxygen, which distinguishes it in both diseases and in their treatment. These bacteria metabolize substances such as carbohydrates to short-chain fatty acids, which strengthen and activate the digestive system, but also have transcendental activity in neurological function, enhancing the blood-brain barrier that separates the brain from the rest of the body.
In a study conducted by Rebecca Nikmeyer of the University of North Carolina, the relationship between the microbiome and the development of the nervous system is investigated: it promotes the development of glia (supporting cells and protection of neurons) of the central nervous system and its myelination. This project investigated animals grown under sterile conditions in which they observed physiological changes in neural development.
Man includes normal microbes from birth and symbiotically builds human life. Many animals cohabit with other lives necessary for functioning. Man needs their intestines, vagina, skin and mouth. This symbiosis is key and will be non-pathological microbes (saprophytes) that inhabit us in life. They will be different in different people, but very similar during the life of each person. In general, one third of the microbiome is the same for different people, the rest are different.
A group of the Karolinska Institute (Pettersson and Diaz Heijtz) studied modifications that occur in the absence of microbes in the intestines of rats. They change their behavior, are less sensitive to stress and change their routines. Before microbes are replaced, the animal returns to its normal behavior, except that sterilization has occurred as a result of the development of the nervous system, where they will continue to be affected as a neurological sign.
Depression, anxiety, obesity, and irritable bowel appear to be involved in a relationship
The embryos contained in us coincide with us at the beginning of life three thousand five hundred million years ago. Then evolution divided us, and those who had a simpler evolution were inside our body as unicellular microbes, billions of them. This set of germs begins at an early age and is generally stable throughout life. One of the first places of incorporation is the birth canal, which contains normal microbes (which creates another need for the study of cesarean section). They are necessary for the health and roommates of our existence.
Important news about the intestinal flora appeared at the US Congress of Neuroscientists. 2018, celebrated in San Diego, California. Rosalind Roberts, Courtney Walker and Charlene Farmer of the Department of Psychiatry and Behavioral Neuroscience at the University of Alabama School of Medicine in Birmingham found that they had detected intestinal bacteria in the human brain. Without generating pathology, we do not know how they got there, perhaps because of the vagus nerve or the blood-brain barrier.
Some scientists suggest that the intestinal nervous system precedes the nervous system and that its great complexity is necessary for the development of the human brain. There will be a genetic transfer between the same microbiome, as well as with our body and nervous system. The intruders who make us up and who provide key information to our brain.
These microorganisms contain a total of three million genes (these genes are called microbiota) compared with the twenty-three thousand genes that humans have and which organize our entire structure and functions. This includes an unusual source of genetic information that needs to be discovered. In the intestine there are billions of bacteria that are interconnected with the digestive system, but also very active with the nervous system. In turn, the intestines contain ten microbes from the body's own cells, which means that our tiny visitors are a clear component of the human body.
Doctor of Medicine and Philosophy.
Prof Tit UBA. Pte Humanas Foundation