The Gut-Brain Axis in Autism: Inflammatory Mechanisms, Molecular Insights, and Emerging Microbiome-Based Therapies

Autism spectrum disorder (ASD) is a complex neurodevelopmental condition with multifactorial etiology, including genetic, environmental, and microbial influences. Recent studies have highlighted the gut-brain axis as a crucial mediator in ASD pathophysiology, linking alterations in gut microbiota to neurodevelopmental and behavioral abnormalities. Individuals with ASD frequently exhibit dysbiosis, characterized by an imbalance in gut microbial composition, reduced microbial diversity, and increased intestinal permeability. These changes contribute to systemic inflammation, altered neurotransmitter synthesis, and metabolic dysfunctions, ultimately impacting brain function. Emerging therapeutic approaches targeting gut microbiome, such as probiotics, prebiotics, dietary modifications, and fecal microbiota transplantation (FMT), have shown potential in alleviating both gastrointestinal (GI) and ASD-related symptoms. This review explores the latest evidence on microbiome alterations in ASD, the mechanisms by which gut dysbiosis influences neurodevelopment, and the therapeutic potential of microbiome-based interventions. Understanding these connections may open new avenues for targeted treatments in ASD management.