The intriguing role of the Gut Microbiome in the etiology and pathogenesis of Neuropsychiatric Disorders

Abstract

Humans live in a symbiotic, evolutionarily endorsed, relationship with the plethora of microbes residing within them, but not until very recently we came to understand that our microbes are more than simply bystanders co-existing with us. They have established a communication, an inter-kingdom connection, with the host’s cells, which is responsible for many physiological aspects concerning human health. The gut microbiome, by its very definition, represents the collective genome material of all microbes inhabiting our intestines, and holds tremendous capacities, for it is able to affect the host in terms of health and disease. It’s intriguing the fact that the gut microbes are engaged not only in local events, but may influence remote tissues and organs as well. Via the gut-brain axis, a multichannel system of pathways connecting the two organs, microbes can affect mood, behavior and cognition and become implicated in the pathogenesis of many neuropsychological disorders. They are able to impact brain function in a variety of ways, however, their true potential lies in their ability to regulate the neural development, a delicate process whose defects can lead to long-term mental health outcomes later in life. In this article, we will review the contribution of the gut microbes in the process of neurodevelopment and attempt to shed light on the etiology of many neuropsychological disorders from the perspective of gut dysbiotic states. Unraveling the mystery behind the true meaning of symbiosis with microbes may provide novel therapeutic strategies against neuro-psychological disorders.