DEVELOPMENT OF TOOLS TO MODULATE ADAM10 TRAFFICKING IN ALZHEIMER’S DISEASE

Alzheimer’s disease (AD) is a progressive neurodegenerative disorder characterized by memory loss and cognitive decline. Recent approval of antibodies targeting amyloid-beta (Abeta) supports the amyloid hypothesis, positing Abeta as a central driver of AD. Abeta is generated from amyloid precursor protein (APP) through sequential cleavage by BACE1 and gamma-secretase. In contrast, the non-amyloidogenic pathway involves APP cleavage by the metalloprotease ADAM10 within the Abeta domain, preventing Abeta formation and releasing neuroprotective soluble APPalpha.
Beyond APP processing, ADAM10 acts as a major synaptic sheddase, regulating morphology and activity-dependent plasticity. In AD, ADAM10 synaptic localization is reduced due to altered trafficking mechanisms, contributing to dysfunction. Notably, increased ADAM10 endocytosis associated with enhanced interaction with clathrin adaptor protein AP2 has been observed in AD patients and experimental models. To counteract this defect, we previously developed a cell-permeable peptide (PEP3) that interferes with ADAM10 endocytosis, enhances its postsynaptic localization and activity, and rescues cognitive deficits in APP/PS1 mice when administered at early disease stages.
To improve the pharmacokinetic properties of this approach, we designed novel peptidomimetics that reproduce PEP3 activity while offering enhanced stability and bioavailability. These compounds were developed to disrupt the ADAM10-AP2 interaction and stabilize ADAM10 at the plasma membrane. Peptidomimetics were characterized by NMR and tested in primary neurons. Target engagement and trafficking effects were assessed using proximity ligation assays, co-immunoprecipitation, quantitative imaging, Western blotting, ELISA, and flow cytometry. Our results demonstrate that the newly developed peptidomimetics efficiently cross biological membranes and significantly increase ADAM10 surface levels and expression.