Stress and the Gut-Brain Axis

Microbiomes and the Digestive System Student's Name Institutional Affiliation Microbiomes and the Digestive System We human beings happen to be microbes. Our bodies largely consist of them in that they outnumber the human cells. Most of these microbes live in the gut, particularly in the large intestines. Microbiomes are genetic materials of all microbes such as viruses, fungi, bacteria, and protozoa that live in the human body. They also outnumber the genes of the human body and they weigh as much as four pounds. Microbiomes in the human body help in digesting food, regulating the immune system and protecting the body against other disease causing bacteria. They are also involved in the production of vitamins, K, B and B12, riboflavin and thiamine which are responsible for blood coagulation. The microbiomes are essential for human development, immunity and nutrition. They are bacteria that live on our bodies and are not threats to our immune system but important colonizers of our body. The microbes start colonizing the mammalian body immediately after birth and continue doing so as throughout the lifetime of an individual. The gut is being signaled by the central nervous system. Any change in dietary pattern due to the control of food intake by the CNS has an impact on the availability of nutrients to the microbes in the gut and their composition. This signaling is done by the peptides that are the key molecular intermediaries between the CNS and gut. The peptides are transported to the brain through the blood system to stimulate satiety (Romijn, 2008). They primarily arise from the GI tract but most of them are synthesized in the brain. At this point the CNS is able to influence microbes through the endocrine and neural pathways both direct and indirect ways (O'Malley, 2011). The influence of microbes on the functions of the central nervous system is based on both normal and disease conditions. Therefore, there exists a link between the microbes and the maturation of the central nervous system under physiological state. The prenatal and postnatal development of the brain can be affected by the external characteristics that are de...