Acupuncture in Autism Spectrum Disorder: A Narrative Review of Neurotransmitter Regulation and Neuroplasticity.

Autism spectrum disorder (ASD) is a heterogeneous neurodevelopmental condition characterized by impairments in social communication, restricted and repetitive behaviors, sensory dysregulation, and frequent psychiatric comorbidities. Increasing attention has been directed toward acupuncture as a complementary neuro-modulatory intervention; however, its underlying molecular mechanisms remain incompletely understood. This review synthesizes evidence from preclinical, clinical, and molecular studies published between 2015 and 2025 to examine how acupuncture influences neurobiological pathways relevant to ASD. Current evidence indicates that acupuncture modulates multiple neurotransmitter systems, including glutamatergic, GABAergic, dopaminergic, serotonergic, and noradrenergic signaling, while also influencing neurotrophin-mediated plasticity, neuroinflammatory responses, and synaptic function. Studies conducted directly in ASD models demonstrate regulation of excitatory/inhibitory balance, monoaminergic signaling, neurotrophin pathways, and ASD-associated behavioral outcomes, whereas evidence from related neuropsychiatric conditions provides complementary mechanistic support for these pathways. Collectively, the findings suggest that acupuncture may act through coordinated modulation of interconnected neurotransmitter and neuroplasticity networks rather than a single molecular target. However, direct mechanistic evidence in ASD-specific models and clinical populations remains limited, and considerable heterogeneity exists among acupuncture protocols and outcome measures. Future studies integrating standardized stimulation paradigms with molecular, electrophysiological, neuroimaging, and behavioral assessments will be essential to validate the proposed mechanisms and clarify the translational potential of acupuncture in ASD.