PEGylated Liposomal Resveratrol Induces Region-Specific Redox Modulation Without Behavioral or Neurotrophin Recovery in a VPA Model of Autism

Abstract

Autism Spectrum Disorder (ASD) is associated with neuroinflammation and oxidative stress that disrupt neurodevelopmental processes. Resveratrol (RSV) is a polyphenol with antioxidant and anti-inflammatory properties, but its poor bioavailability limits therapeutic use. This study investigated whether PEGylated liposomes encapsulating RSV (LipRSV) could modulate oxidative and behavioral alterations in a valproic acid (VPA)-induced rat model of ASD. PEGylated LipRSV were synthesized, characterized as hemocompatible, and administered to offspring from postnatal day (PND) 6 to 27. Behavioral tests included developmental milestones, olfactory discrimination, negative geotaxis, open field, and three-chamber social interaction. Oxidative stress markers and neurotrophins (BDNF, NGF) were quantified in the following brain regions: hippocampus, hypothalamus, striatum, cerebellum, frontal and posterior cortex. LipRSV exerted limited and region-dependent redox effects, reducing ROS levels only in the hippocampus, cerebellum, and posterior cortex, while failing to improve behavioral outcomes and being associated with unfavorable neurochemical alterations, including reduced BDNF and NGF levels. Importantly, LipRSV also induced behavioral deficits, redox imbalance, and neurochemical alterations in control animals, indicating treatment-related effects in the absence of VPA exposure. LipRSV modulated oxidative stress in a region-dependent manner without improving behavioral deficits in the VPA model and was associated with reduced BDNF and NGF levels. This study provides evidence that modulation of oxidative stress alone is insufficient to rescue behavioral phenotypes in the VPA model of ASD. These findings highlight the partial neurochemical efficacy and translational limitations of this formulation, suggesting the need for optimized nanocarrier design and dosing strategies in ASD pharmacotherapy.