Gut-Microbiota-Brain Axis and Depression

  • Alper EvrenselEmail author
  • Mehmet Emin Ceylan


Contrary to the general belief, a fetus is not sterile. Gut microbiota becomes colonized to the fetus in the intrauterine period. Microorganisms play a very significant role in the development of the immune system and the brain of the fetus. There is a bidirectional symbiotic relationship between gut microbiota and the body. This interaction is determinant on human health. Gut microbiota has fundamental effects on neurodevelopmental processes such as blood-brain barrier formation, myelination, and neurogenesis. There is a relationship between dysbiosis of microbiota and neuropsychological disorders, particularly depression. Colonization of pathogen bacteria in the gut and their metabolites (endotoxins) leads to immune response. Microorganisms affect the brain via the immune system, neuroendocrine system, and nervus vagus. Nutrition, stress, and medication lead to dysbiosis by changing the microbiota composition. It is also possible to purposefully manipulate the gut microbiota. Dysbiosis may be restored by changing gut bacteria composition with probiotics and fecal microbiota transplantation (FMT). Probiotic bacteria have a potential to be used in depression treatment. FMT may be a sign of hope in treatment-resistant depression in the future. The door to the mysterious world of gut-brain relationship seems to have just been opened.


Depression Gut-brain axis Microbiota Probiotics Fecal microbiota transplantation 


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© Springer Nature Singapore Pte Ltd. 2018

Authors and Affiliations

  1. 1.Department of PsychiatryUskudar UniversityIstanbulTurkey

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