A pilot study of the plasma and urinary neurotransmitters in Chinese children with autism spectrum disorder

A significant negative correlation was observed between plasma GABA neurotransmitter concentrations and ASD severity. In contrast, NE and NMN levels in urine showed significantly positive correlations with ASD severity. Both excessively low and excessively high plasma NE and Tyr levels may be associated with more severe autism symptoms, suggesting a disruption in peripheral neurotransmitter levels in children with ASD. Future studies with larger sample sizes are required for prediction and validation. The peripheral neurotransmitters may serve as potential auxiliary biomarkers for assessing the severity of autism.