Abstract

The bidirectional communication pathway known as the gut-brain axis is discussed with regard to both gut-to-brain and brainto- gut communications. In particular, the influence of the gut microbiota on the development of emotional behavior, stress- and painmodulation systems, as well as brain neurotransmitter systems is reviewed. The literature on the potential role of the gut microbiota on central nervous disorders such as autism and anxiety-depressive behaviors as well as its role in Parkinson’s and Alzheimer’s disease is reviewed. The potential contribution of intestinal dysbiosis to psychiatric disorders in patients with bowel disorders is also considered.

The literature on the influence of the brain on gut bacteria, notably disruption of the microbial balance within the gut and promoting inflammatory bowel disease, is discussed. Disturbance of homeostasis within the body and particularly the GI system apparently increases susceptibility to infectious disease and also can trigger a cascade of molecular reactions. These reactions can feed back to the central nervous system and the brain via the gut-brain axis, adversely affect the brain and behavior.

Finally, gut dysbiosis and its health sequalae are reassessed together with the potential benefits derived from ingesting prebiotics and probiotics on gut, brain and systemic health.

Keywords: Gut-Brain Axis; Gut Microbiota; Prebiotics; Probiotics

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