β-Amyloid: Structure, Properties, and Link with Alzheimer’s Disease

Abstract Under certain conditions, peptides and proteins are capable of conversion from their soluble native form to insoluble, highly ordered fibrillar aggregates. Alzheimer’s disease is a progressive neurodegenerative disease, whose development is accompanied by a steady decline in the patient’s condition, loss of the ability to live independently, and ultimately death. Currently, there are tens of millions of people in the world with Alzheimer’s disease, but there are still no effective methods for combating this disease. One of the key pathomorphological attributes of Alzheimer’s disease is the formation of senile plaques: accumulations of β‑amyloid fibrils, the main components of which are β-amyloid peptides (Aβ), having a molecular weight and length of about 4 kDa and 40 amino acid residues, respectively. The review is devoted to the structural features of Aβ peptides, the mechanism of their aggregation leading to the formation of various Aβ oligomeric forms, protofibrils, protofilaments, and ultimately fibrils, as well as their biological role and link with Alzheimer’s disease. Modern scientific approaches aimed at inhibiting Aβ peptide aggregation by the action of various inhibitors on Aβ monomers, Aβ oligomers, as well as the surface of formed Aβ protofilaments and fibrils, are considered.