A Prodrug Approach for Activity-Based Chemical Modulation toward Multiple Pathological Targets in Alzheimer's Disease

Area of Science:

• Neuroscience
• Medicinal Chemistry
• Biochemistry

Background:

• Alzheimer's disease (AD) is characterized by oxidative stress, amyloid-beta (Aβ) aggregation, and metal ion imbalance.
• Elevated hydrogen peroxide (H2O2) in AD brains creates an oxidative environment suitable for targeted drug activation.

Purpose of the Study:

• To design and evaluate a novel prodrug platform that utilizes H2O2 as an endogenous trigger for redox-based therapy in AD.
• To investigate the prodrug's ability to modulate multiple pathological features of AD simultaneously.

Main Methods:

• Development of boronic ester-masked precursors (BE-1, BE-2) designed for H2O2-triggered activation.
• Biochemical and biophysical analyses to assess the prodrug's activity, including reactive oxygen species scavenging and Aβ modification.
• In vivo studies using AD transgenic mice to evaluate brain conversion, oxidative stress reduction, plaque burden, and cognitive function.

Main Results:

• Prodrugs BE-1 and BE-2 were successfully synthesized and remained inert until exposed to H2O2.
• Activated prodrugs scavenged reactive oxygen species and modified Aβ aggregation pathways.
• In AD mice, BE-1 converted to its active form in the brain, reducing oxidative stress, amyloid plaques, and improving cognitive deficits.

Conclusions:

• A rationally designed, H2O2-responsive prodrug platform offers a precise strategy for AD therapy.
• This activity-based prodrug approach effectively targets multiple interconnected drivers of neurodegeneration.
• The prodrug strategy demonstrates potential for simultaneous modulation of AD pathology and improvement of cognitive function.