Oral edaravone ameliorates behavioral deficits and pathologies in a valproic acid-induced rat model of autism spectrum disorder

Abstract

Autism spectrum disorder (ASD) is neurodevelopmental disorder with a high incidence rate, characterized by social deficits and repetitive behaviors. There is currently no effective management available to treat the core symptoms of ASD; however, oxidative stress has been implicated in its pathogenesis. Edaravone (EDA), a free-radical scavenger, is used to treat amyotrophic lateral sclerosis (ALS) and acute ischemic stroke (AIS). Here, we hypothesized that an oral formula of EDA may have therapeutic efficacy in the treatment of core ASD symptoms. A rat model of autism was established by prenatal exposure to valproic acid (VPA), and the offsprings were orally treated with EDA at low (3 mg/kg), medium (10 mg/kg), and high (30 mg/kg) doses once daily for 28 days starting from postnatal day 25 (PND25). Oral EDA administration alleviated the core symptoms in VPA rats in a dose-dependent manner, including repetitive stereotypical behaviors and impaired social interaction. Furthermore, oral administration of EDA significantly reduced oxidative stress in a dose-dependent manner, as evidenced by a reduction in oxidative stress markers and an increase in antioxidants in the blood and brain. In addition, oral EDA significantly attenuated downstream pathologies, including synaptic and mitochondrial damage in the brain. Proteomic analysis further revealed that EDA corrected the imbalance in brain oxidative reduction and mitochondrial proteins induced by prenatal VPA administration. Overall, these findings demonstrate that oral EDA has therapeutic potential for ASD by targeting the oxidative stress pathway of disease pathogenesis and paves the way towards clinical studies.