Microbiota-gut brain axis involvement in neuropsychiatric disorders

ABSTRACT

Introduction: The microbiota-gut brain (MGB) axis is the bidirectional communication between the intestinal microbiota and the brain. An increasing body of preclinical and clinical evidence has revealed that the gut microbial ecosystem can affect neuropsychiatric health. However, there is still a need of further studies to elucidate the complex gene–environment interactions and the role of the MGB axis in neuropsychiatric diseases, with the aim of identifying biomarkers and new therapeutic targets, to allow early diagnosis and improving treatments.

Areas covered: To review the role of MGB axis in neuropsychiatric disorders, prediction and prevention of disease through exploitation, integration, and combination of data from existing gut microbiome/microbiota projects and appropriate other International ‘-Omics’ studies. The authors also evaluated the new technological advances to investigate and modulate, through nutritional and other interventions, the gut microbiota.

Expert opinion: The clinical studies have documented an association between alterations in gut microbiota composition and/or function, whereas the preclinical studies support a role for the gut microbiota in impacting behaviors which are of relevance to psychiatry and other central nervous system (CNS) disorders. Targeting MGB axis could be an additional approach for treating CNS disorders and all conditions in which alterations of the gut microbiota are involved.

KEYWORDS:

• Ketogenic diet
• microbiota-gut brain axis
• inflammation
• manipulating microbiota
• metabolomics
• neuropsychiatric disorders

Article highlights

• The gut microbiota is a highly dynamic and complex system with approximately 10¹⁴ cells of 1.000 different species.

• The host-microbiota communication pathways, above all the main microbiota-gut brain (MGB) axis network, are fundamental mechanisms to preserve a healthy human holobiont.

• Deep changes in diversity, loss of commensals, and bloom of pathobionts can cause a dysbiosis and the leak of microbiota from its functional range.

• Sequencing technologies are revolutionizing the field of microbiota research to fully understand the various aspects of host-microbial mutualism.

• Promising applications in the medical field is allowing the identification of metabolic patterns of metabolites at single patient level, a useful tool to understand the etiology of a disease and to follow its progression over time.

• Gut microbiota can affect neural circuits and behavior related to stress response and his compositional alterations can lead to an immune system activation, with local and systemic pro-inflammatory state and more permissive intestinal barrier.

Targeted therapies focused on microbiota will likely play a large role in the future.

Acknowledgments

“The Gut-Brain-Microbiome connection in neuropsychiatric diseases of children and adults” workshop (Genova, April 27–28th, 2018) was supported by Kolfarma, Fb Health, Ecupharma and by University of Genova (travel grant to PS). We also thank Leandro and Jacopo Nencioni (J Medical Books Ed. S.r.l.) for their support.

Declaration of interest

P Striano has received a travel grant from Kolfarma S.R.L. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or conflict with the subject matter or materials discussed in this manuscript apart from those disclosed.

Reviewer disclosures

Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Additional information

Funding

This paper was not funded.