Serum hypoxia-inducible factor-1 alpha (HIF-1α) and apelin levels in children and adolescents diagnosed with autism spectrum disorder

Background: Autism spectrum disorder (ASD) is a neurodevelopmental disorder in which underlying etiological factors remains unclear. The important environmental factors associated with ASD, include neuroinflammation, hypoxia, and oxidative stress. HIF-1α and apelin are biochemical markers that play important roles in neuroinflammation, hypoxia and oxidative stress. The aim of this study is to determine whether serum HIF-1α and apelin levels differ between children and adolescents with Autism Spectrum Disorder (ASD) and healthy controls. Methods: This cross-sectional study included 30 children and adolescents with ASD and 30 healthy controls. HIF-1α and apelin serum levels were measured using commercial enzyme-linked immunosorbent assay kits. Autism symptom severity was evaluated using Childhood Autism Rating Scale (CARS). HIF-1α and apelin serum levels were compared between groups. Additionally, correlations between HIF-1α and apelin serum levels and sociodemographic-clinical variables (age, BMI, CARS total score, ASD severity, psychiatric medication use, psychiatric comorbidity, NLR, SII) were evaluated in the ASD group. Results: Serum HIF-1α and apelin levels were statistically significantly higher in the ASD group (p = 0.044, p = 0.041 respectively). Serum apelin levels were negatively correlated with age (r = −0.430, p = 0.018). Serum HIF-1α levels were positively correlated with NLR (r = 0.627 p < 0.001) and SII (r = 0.609 p < 0.001). There was positive correlation between serum apelin levels and NLR (r = 0.525 p = 0.003) and SII (r = 559 p = 0.002). Conclusion: These results suggest that, HIF-1α and apelin may play a potential role in the etiopathogenesis of ASD. Further studies on the subject are needed to reveal the causality between HIF-1α, apelin and ASD.