Profiling plasma levels of thiamine and histamine in Jordanian children with autism spectrum disorder (ASD): potential biomarkers for evaluation of ASD therapies and diet

Background: The current work involved monitoring two biomarkers in the plasma of children with ASD: the cofactor thiamine that is involved in neurotransmitters modulation for acetylcholine, and the compound histamine, which acts as a neuromodulator by regulating the release of other neurotransmitters. This is the first report to highlight the potential utilization of plasma levels of the selected two brain-related biomarkers in children with ASD. Methods: A total of 43 children with ASD of both genders (age 4–12 years) were involved in this study and compared to age and gender-matched control children (n = 42). The diagnosis of ASD was based on the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM5), followed by an additional assessment using the Childhood Autism Rating Scale (CARS). All participants were Jordanian children on Mediterranean diet, and had no history of chronic illness or medications. Measurement of thiamine and histamine in plasma was performed using enzyme-linked immunosorbent assay (ELISA). Results: The outcomes revealed that average histamine levels (31.7 ± 18.5 ng/ml) of ASD group were 5.3× higher (p <.001) compared to their control (0.013 ± 0.011 ng/ml; 6.03 ± 4.25 ng/ml), while thiamine (10.78 ± 7.49 ng/ml) levels of ASD group were significantly lower (p <.001) than the control (37.92 ± 26.87 ng/ml; 0.209 ± 0.054 ng/ml). Conclusions: The study is proposing that monitoring of the plasma levels of thiamine and histamine as biomarkers for future evaluation and development of ASD therapies and nutritious diets.