Evaluation of oxytocin and serotonin levels in autism spectrum disorder

Abstract

Objective Autism spectrum disorder (ASD) is a complex neurological and developmental disorder that affects how a person acts and interacts, communicates with others, and learns. Endocrine and neuropeptide factors are some among the list of possible etiologic or predisposing contenders. Abnormalities in the brain serotonin system are reported in ASD, including evidence of altered serotonin synthesis and receptor binding, as well as dystrophic serotonergic axons. Blood oxytocin levels are also a focus of ASD research. This work aimed to assess oxytocin and serotonin levels as biomarkers in individuals with ASD. Participants and methods Serotonin and oxytocin levels, as biochemical parameters related to neurochemistry, were determined in the sera of 40 autistic patients (29 males and 11 females). They were categorized as mild to moderate and severe as indicated by their Childhood Autism Rating Scale and as low average intelligence, slow learner, and mentally retarded according to their intelligence quotients. The parameters were then compared with that of 40 age-matched and sex-matched control samples (30 males and 10 females). Results Our patients showed a highly significant increase in serotonin levels and a highly significant decrease in oxytocin levels as compared to controls. Diagnostic validity test was carried out for both serotonin and oxytocin and showed excellent results. A correlation done between serotonin and oxytocin levels among the patient group showed significant negative correlation. Conclusion Our results significantly reinforce the reliability of increased serotonin blood levels and decreased oxytocin levels as biomarkers in ASD, providing possible indications potentially useful for their inclusion in multimarker diagnostic panels for clinical use. Identifying relationships between identified ASD biomarkers may be a useful approach to connect the different findings of multiple systems in this heterogeneous disorder and to find the causesof ASD and to identify potential interventions.