The Gut Microbiota and Dysbiosis in Autism Spectrum Disorders
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Purpose of Review
There is a growing body of evidence indicating the gut microbiota influence neurodevelopment and behavior. The purposes of this review are to provide an overview of studies analyzing the microbiota and their metabolites in autism spectrum disorders (ASD) and to discuss the possible mechanisms of action involved in microbial influence on the brain and behavior.
The microbiota-gut-brain (MGB) axis has been extensively studied in animal models, and it is clear that alterations in the composition of microbiota alter neurological and behavioral outcomes. However, findings in human studies are less abundant. Although there are several studies so far showing altered microbiota (dysbiosis) in ASD, the results are heterogeneous and often contradictory. Intervention studies such as fecal microbiota transplant therapies show promise and lend credence to the involvement of the microbiota in ASD.
A role for the microbiota in ASD is likely; however, further studies elucidating microbial or metabolomic signatures and mechanisms of action are needed. Future research should focus on intervention studies that can identify specific metabolites and immune mediators that improve with treatment to help identify etiologies and pathological mechanisms of ASD.
KeywordsAutism Microbiota Dysbiosis Dysregulation Neurodevelopment Behavior
Investigators were funded by the NIEHS Children’s Center grant (P01 ES011269), US EPA STAR program grant (R833292 and R829388), NIEHS CHARGE study (R01ES015359), NICHD (HD086669, HD090214 and U54 HD079125), Autism Research Institute, Autism Speaks Foundation, The Boler Company Foundation, NARSAD Foundation and the Johnson Foundation. This material is based upon work supported by the National Science Foundation Graduate Research Fellowship under Grant No. 1650042.
Compliance with Ethical Standards
Conflict of Interest
Heather K. Hughes, Destanie Rose, and Paul Ashwood each declare no potential conflicts of interest.
Human and Animal Rights
This article does not contain any studies with human or animal subjects performed by any of the authors.
Papers of particular interest, published recently, have been highlighted as: • Of importance •• Of major importance
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