Soluble alpha-klotho as a new indicator for autism spectrum disorder and its relation to oxidative stress

Protein soluble alpha-klotho (S-KLα) slows down the aging process and has multiple effects, notably on the nervous system. Autism spectrum disorder (ASD) is a global health issue that must be recognized, prevented, and treated. This study aimed to investigate the clinical significance of S-KLα as a novel marker for diagnosing ASD and to explore its correlation with oxidative stress. The study included children older than 2 years and younger than 16 years, comprising 100 healthy children and 100 children with ASD. Serum S-KLα levels were determined using ELISA. Additionally, iron, uric acid, GSH, vitamin E (Vit_E), ONOO⁻, and MDA levels, as well as arylesterase activity, were measured, and statistical analyses were performed. Patients with ASD had lower serum S-KLα levels than the control group. The area under the curve (AUC) value (0.888, p < 0.0001 for S-KLα), with a sensitivity of 0.765 and a specificity of 0.921, indicates that S-KLα is a reliable additional predictor of ASD. Furthermore, a significant inverse correlation was found between S-KLα and MDA. In contrast, significant positive correlations were observed between serum S-KLα and iron, GSH, Vit_E, and arylesterase activity in patients with ASD. This study is the first to demonstrate that serum S-KLα could serve as a useful marker for predicting ASD. It also reveals interesting links between S-KLα and oxidative stress that could lead to new diagnostic and therapeutic approaches for ASD.