doi: 10.56294/shp2024106

 

SHORT COMMUNICATION

 

The gut-brain axis and neurodevelopment: microbial correlations in autism

 

Eje intestino-cerebro y neurodesarrollo: correlaciones microbianas en el autismo

 

Camila Tamara Pereira de Arruda1  *, Patricia Susana Salguero1  *

 

1Universidad Abierta Interamericana, Facultad de Medicina y Ciencias de la Salud, Carrera de Medicina. Buenos Aires, Argentina.

 

Cite as: Pereira de Arruda CT, Salguero PS. The gut-brain axis and neurodevelopment: microbial correlations in autism. South Health and Policy. 2024; 3:106. https://doi.org/10.56294/shp2024106  

 

Submitted: 28-06-2023          Revised: 01-10-2023          Accepted: 22-01-2024          Published: 23-01-2024

 

Editor: Dr. Telmo Raúl Aveiro-Róbalo  

 

Corresponding Author: Camila Tamara Pereira de Arruda *

 

ABSTRACT

 

Autism Spectrum Disorder (ASD) was described as a neurodevelopmental condition characterised by difficulties in social communication and repetitive behaviours. In Argentina, as in other countries, an increase in its prevalence has been observed. The relationship between ASD and the gut microbiota was investigated, finding significant differences in children with ASD compared to neurotypical children, particularly in bacteria such as Clostridium, Bacteroides, and Desulfovibrio. A study published in 2024 identified 31 biological markers in faecal samples from children with ASD, suggesting a possible use of the microbiome as a diagnostic tool. However, some researchers proposed that these alterations could be due to selective eating behaviours. Various interventions were explored, such as specific diets, probiotics, prebiotics and faecal microbiota transplants. In Argentina, interest in this integrative approach grew, highlighting the gut-brain axis as a relevant component in understanding and addressing ASD.

 

Keywords: Autism Spectrum Disorder (ASD); Dysbiosis; Microbiota; Diagnosis; Neurodevelopment.

 

RESUMEN

 

El Trastorno del Espectro Autista (TEA) fue descrito como una condición del neurodesarrollo con dificultades en la comunicación social y conductas repetitivas. En Argentina, al igual que en otros países, se observó un aumento en su prevalencia. Se investigó la relación entre el TEA y la microbiota intestinal, encontrándose diferencias significativas en niños con TEA respecto a los neurotípicos, particularmente en bacterias como Clostridium, Bacteroides y Desulfovibrio. Un estudio publicado en 2024 identificó 31 marcadores biológicos en muestras fecales de niños con TEA, lo que sugirió un posible uso del microbioma como herramienta diagnóstica. Sin embargo, algunos investigadores propusieron que estas alteraciones podrían deberse a conductas alimentarias selectivas. Se exploraron diversas intervenciones, como dietas específicas, probióticos, prebióticos y trasplantes de microbiota fecal. En Argentina, el interés por este enfoque integrador creció, destacándose el eje intestino-cerebro como un componente relevante en el entendimiento y abordaje del TEA.

 

Palabras clave: Trastorno Del Espectro Autista (TEA); Disbiosis; Microbiota; Diagnóstico; Neurodesarrollo.

 

 

 

BACKGROUND

Autism Spectrum Disorder (ASD) is a neurodevelopmental condition characterized by difficulties in social communication and repetitive behaviors.(1) In Argentina, as in other countries, there has been an increase in the prevalence of ASD, with an estimated one in 44 children having the disorder.(2) At the same time, research into the gut microbiota and its influence on various neurological conditions, including ASD, has intensified.

Gut dysbiosis refers to an imbalance in the composition of the gut microbiota. Numerous studies have identified significant differences in the microbiota of children with ASD compared to neurotypical children.(3) For example, alterations have been found in Clostridium, Bacteroides, and Desulfovibrio. These differences could influence communication between the gut and the brain, affecting behavior and cognitive function.(4)

A study published in Nature Microbiology 2024 analyzed fecal samples from more than 1600 children, identifying 31 distinctive biological markers in those with ASD.(5) These findings suggest that the gut microbiome could be a valuable tool for the early diagnosis of autism.

However, some researchers argue that dysbiosis could be a consequence of selective eating behaviors common in children with ASD rather than a direct cause of the disorder.(6,7)

The gut-brain axis is a two-way communication pathway between the gastrointestinal and central nervous systems.(8,9) The gut microbiota plays a crucial role in this axis, influencing neurotransmitter production and modulating the immune response.(10,11) Alterations in this axis could contribute to the symptoms observed in ASD.

Various interventions have been explored to correct dysbiosis in children with ASD, including:(12,13,14,15,16)

•     Diet: A diet rich in fiber and low in processed foods may promote healthy microbiota.

•     Probiotics and Prebiotics: Some studies have shown promising results from the use of supplements that promote the growth of beneficial bacteria.

•     Fecal Microbiota Transplant: Although still in the experimental stages, this technique has been explored as a possible intervention to restore microbial balance.

 

In Argentina, interest in the relationship between microbiota and ASD has grown, highlighting the microbiome’s importance in neurological health and its potential role in ASD.(17,18)

The relationship between intestinal dysbiosis and ASD is a growing field of research. While evidence suggests a connection, more studies are needed to fully understand the nature of this relationship and its clinical applicability. In Argentina, growing interest and ongoing research offer an opportunity to advance the diagnosis and treatment of ASD from an integrative perspective that considers gut health as a key component.

 

BIBLIOGRAPHICAL REFERENCES

1.  que é o Autismo? [Internet]. Autismo e Realidade. Disponible en: https://autismoerealidade.org.br/o-que-e-o-autismo/

 

2.  Autismo [Internet]. Organización Mundial de la Salud;. Disponible en: https://www.who.int/es/news-room/fact-sheets/detail/autism-spectrum-disorders

 

3.  Álvarez J, Fernández Real JM, Guarner F, Gueimonde M, Rodríguez JM, Saenz de Pipaon M, et al. Gut microbes and health. Gastroenterol Hepatol. 2021;44(7):519-35.

 

4.  Kang DW, Adams JB, Gregory AC, Borody T, Chittick L, Fasano A, et al. Microbiota transfer therapy alters gut ecosystem and improves gastrointestinal and autism symptoms: an open-label study. Microbiome. 2017 Jan 23;5(1):10.

 

5.  Berding K, Donovan SM. Diet can impact microbiota composition in children with autism spectrum disorder. Front Neurosci. 2018;12:515.

 

6.  Niu M, Li Q, Zhang J, Wen F, Dang W, Duan G, et al. Characterization of intestinal microbiota and probiotics treatment in children with autism spectrum disorders in China. Front Neurol. 2019;10:1084.

 

7.  Sanctuary MR, Kain JN, Chen SY, Kalanetra K, Lemay DG, Rose DR, et al. Pilot study of probiotic/colostrum supplementation on gut function in children with autism and gastrointestinal symptoms. PLoS One. 2019;14(1):e0210064.

 

8.  Plaza-Díaz J, Gómez-Fernández A, Chueca N, de la Torre-Aguilar MJ, Gil Á, Perez-Navero JL, et al. Autism spectrum disorder (ASD) with and without mental regression is associated with changes in the fecal microbiota. Nutrients. 2019 Feb 5;11(2):337.

 

9.  Cryan JF, O’Riordan KJ, Cowan CSM, Sandhu KV, Bastiaanssen TFS, Boehme M, et al. The microbiota-gut-brain axis. Physiol Rev. 2019 Oct 1;99(4):1877-2013.

 

10.  Hsiao EY, McBride SW, Hsien S, Sharon G, Hyde ER, McCue T, et al. Microbiota modulate behavioral and physiological abnormalities associated with neurodevelopmental disorders. Cell. 2013 Dec 19;155(7):1451-63.

 

11.  Moreno X, Santamaria G, Sánchez R, de la Torre B, Garcés F, Hernández C, et al. Microbiota gastrointestinal aeróbica en niños con trastorno del espectro autista. Estudio preliminar. Gen. 2015 Jul;69(2):36-44.

 

12.  Fattorusso A, Di Genova L, Dell’Isola GB, Mencaroni E, Esposito S. Autism spectrum disorders and the gut microbiota. Nutrients. 2019 Feb 28;11(3):521.

 

13.  Dinan TG, Cryan JF. The microbiome-gut-brain axis in health and disease. Gastroenterol Clin North Am. 2017 Mar;46(1):77-89.

 

14.  Marler S, Ferguson BJ, Lee EB, Peters B, Williams KC, McDonnell E, et al. Association of rigid-compulsive behavior with functional constipation in autism spectrum disorder. J Autism Dev Disord. 2017 Jun;47(6):1673-81.

 

15.  Shaaban SY, El Gendy YG, Mehanna NS, El-Senousy WM, El-Feki HSA, Saad K, et al. The role of probiotics in children with autism spectrum disorder: a prospective, open-label study. Nutr Neurosci. 2018 Nov;21(9):676-81.

 

16.  Kang DW, Ilhan ZE, Isern NG, Hoyt DW, Howsmon DP, Shaffer M, et al. Differences in fecal microbial metabolites and microbiota of children with autism spectrum disorders. Anaerobe. 2018 Feb;49:121-31.

 

17.  Buie T, Campbell DB, Fuchs GJ, Furuta GT, Levy J, Vandewater J, et al. Evaluation, diagnosis, and treatment of gastrointestinal disorders in individuals with ASDs: a consensus report. Pediatrics. 2010 Jan;125 Suppl 1:S1-18.

 

18.  McElhanon BO, McCracken C, Karpen S, Sharp WG. Gastrointestinal symptoms in autism spectrum disorder: a meta-analysis. Pediatrics. 2014 May;133(5):872-83.

 

FUNDING

None.

 

CONFLICT OF INTEREST

None.

 

AUTHOR CONTRIBUTION

Conceptualization: Camila Tamara Pereira de Arruda, Patricia Susana Salguero.

Writing – original draft: Camila Tamara Pereira de Arruda, Patricia Susana Salguero.

Writing – review and editing: Camila Tamara Pereira de Arruda, Patricia Susana Salguero.