Amyloid, The Amyloid B -Peptide and Alzheimer’s Disease: Structural Considerations - Molecules: Nucleation, Aggregation and Crystallization - page 283

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Amyloid, The Amyloid -Peptide

and Alzheimer's Disease: Structural
Considerations

β

Lars O. Tjernberg*

Several proteins can form ordered, protease-resistant fibrillar deposits, called amy-
loid, in the human body. Amyloid is associated with several different diseases, amy-
loidoses, including Alzheimer's disease. This progressive neurodegenerative
disease affects around 1% of the population of the Western world. The disease is
pathologically characterized by amyloid deposits composed of fibrils formed by the
amyloid β-peptide, Aβ, and it has been suggested that compounds that interfere with
Aβ-polymerization could be used for treatment of Alzheimer's disease. Several
studies aimed at revealing the structure of Aβ in solution and in amyloid fibrils have
been performed. Structural studies of Aβ and other amyloid proteins are problem-
atic since these proteins have poor solubility and do not form crystals. However,
with the help of a combination of several different, mostly spectroscopic, techniques
the structure of Aβ is being resolved. Here, we will give an introduction to amyloid,
Alzheimer's disease, Aβ and different techniques used for studying Aβ structure.
Finally, we will look at Aβ-polymerization and how this process can be inhibited.

Keywords: Amyloid; amyloid β-peptide; Alzheimer's disease; polymerization;
β-sheet; spectroscopy.

Introduction

The term “amyloid” means starch-like, and was first used in the 1850s to
describe histological deposits that were stained with iodine. These deposits

*Karolinska Institutet, Department of NVS, KI-Alzheimer's Disease Research Center,
KASPAC — Phone: + 46 8 585 83620. E-mail: [e-mail].