Tocovid Attenuated Oxidative Stress and Cognitive Decline by Inhibiting Amyloid-β-Induced NOX2 Activation in Alzheimer’s Disease Mice

Background: NADPH oxidase 2 (NOX2) is an important source of reactive oxygen species (ROS). Activated NOX2 may contribute to Alzheimer’s disease (AD). Our previous studies showed that a novel vitamin E mixture, Tocovid, had potential neuroprotective effects in a stroke mice model and an AD cell model. Objective: The aim of this study was two-fold: to assess whether long-term Tocovid treatment can regulate NOX2, and the therapeutic effects of long-term administration of Tocovid to an AD mice model. Methods: Therapeutic effects of long-term administration of Tocovid (200 mg/kg /day) on an Aβ-overexpressed transgenic AD mice model (APP23, n = 8) was investigated. The therapeutic effect of Tocovid in 16-month-old mice compared with the no-treatment APP23 group (n = 9) was assessed. Results: Tocovid treatment strongly improved motor and memory deficits of APP23 mice by attenuating NOX2 expression, oxidative stress, neuroinflammation, neurovascular unit dysfunction, synaptic alteration, and Aβ deposition after 16 months. Conclusion: These findings suggest that NOX2 is a potential target in AD pathology. Long-term administration of Tocovid may be a promising candidate for AD treatment.