New Perspectives in Reducing Amyloid Aggregation and Toxicity

One of the fundamental biochemical characteristics of Alzheimer′s Disease (AD) is the intercellular accumulation of amyloid beta (Aβ) peptide plaques in the brain. Although there is not yet a cure for AD, major efforts have been made to identify antiamyloidogenic agents and therapeutic strategies to treat this disease and related conditions. Our group focuses on inhibiting the aggregation and toxicity of Aβ using two distinct approaches. The first involves covalently attaching the sequence-derived core amyloidogenic amino acid fragment KLVFF to the surfaces of serum albumin microspheres. These particles bind soluble Aβ with high affinity, inhibit its aggregation, reduce its toxicity, and decrease the inflammation induced by its aggregates. Microsphere-bound Aβ stimulates microglia and is phagocytosed via a different mechanism from that used for Aβ removal, so enabling its clearance even by defective cells. Our second approach utilizes self-assembled cyclic D,L-α-peptides as conformational mimics of the amyloid fibril architecture that inhibit the aggregation and cytotoxicity of Aβ. Here, we review these strategies and their mechanisms of action.