Gut microbiota and its metabolism in autism spectrum disorder: from pathogenesis to therapy.

This review looks at how gut bacteria might be connected to autism. Nearly half of autistic people have stomach problems like pain and diarrhea. The research shows that autistic people often have different gut bacteria compared to others, with less variety and different bacterial balance. These gut changes might affect autism symptoms through the connection between the gut and brain.

Treatments that target gut bacteria, like special diets, probiotics, and exercise, may help improve both stomach problems and autism behaviors.

This comprehensive review examines the relationship between gut microbiota and autism spectrum disorder (ASD). The analysis reveals that ASD patients commonly experience gastrointestinal symptoms (nearly 50% of cases) and demonstrate altered gut microbiota composition, including reduced diversity and imbalanced bacterial ratios. The gut-brain axis emerges as a critical pathway through which microbiota abnormalities influence ASD symptoms via multiple mechanisms: metabolite disruption (affecting neurotransmitters and inflammation), immune pathway alterations, and compromised barrier functions. Various microbiota-targeted interventions show promise for alleviating both gastrointestinal and behavioral symptoms.

However, the review identifies significant knowledge gaps in metabolite regulation mechanisms and notes considerable individual variation in treatment responses, emphasizing the need for personalized approaches and advanced research methodologies.

Results support integrating gastrointestinal assessment and gut microbiota-targeted interventions into autism care. Clinicians should consider dietary modifications, probiotics, and exercise as adjunct treatments. However, significant individual variation necessitates personalized approaches. The gut-brain axis provides a valuable framework for understanding autism symptoms and developing comprehensive treatment strategies.

The review identifies unclear metabolite regulation mechanisms and significant individual differences in intervention responses. As a review paper, findings depend on the quality of underlying studies. The lack of reported sample sizes and heterogeneity of included studies limits strength of conclusions.

Autism Spectrum Disorder (ASD) is a complex neurodevelopmental disorder characterized by social communication deficits and repetitive behaviors. Studies show that nearly half of ASD patients have gastrointestinal symptoms such as abdominal pain and diarrhea, indicating the important role of gut microbiota in its pathogenesis. This review finds that ASD patients exhibit reduced gut microbiota diversity and imbalanced Bacteroidetes/Firmicutes ratio, with abnormal microbial structure affecting neurobehavior through the gut-brain axis. Abnormalities in gut microbiota metabolites (short-chain fatty acids, phenolic compounds, bile acids, amino acids, etc.) are key mediators, which can exacerbate symptoms by affecting BBB permeability, neuroinflammation, and neurotransmitter balance.

The gut-brain axis regulates ASD through mechanisms including the HPA axis, vagus nerve, immune pathways, and barrier functions. Gut microbiota-targeted interventions (exercise, dietary intervention, fecal microbiota transplantation, prebiotics/probiotics, etc.) can alleviate gastrointestinal and behavioral symptoms of ASD by regulating microbiota balance and improving metabolic environment. However, there are still issues such as unclear metabolite regulation mechanisms and significant individual differences in interventions. Future studies should combine multi-omics and artificial intelligence to identify core targets, develop personalized plans, and promote clinical translation.