As the average human lifespan has increased, diseases that have higher incidence with increasing age have become a research priority in many labs around the world. One of these age-related diseases is Alzheimer's.

Patients with Alzheimer's disease suffer gradual loss of memory and judgement, and are eventually incapable of performing basic tasks such as eating. One of the physical hallmarks of Alzheimer's is the formation of clusters of proteins between and inside nerve cells of the brain. These protein clumps, called plaques, damage the brain's nerve cells, resulting in the set of symptoms (i.e. memory loss, emotional instability) observed in Alzheimer's patients.

Nowadays, there are drugs that can reduce the severity of the symptoms of Alzheimer's disease in its early stages; but no treatment can prevent or stop the progression of this degenerative disease. However, researchers continue to take on the challenge of unraveling the mysteries locked in the brains of Alzheimer's patients.

Fifteen years ago, it was found that the main component of the plaques that formed between the nerve cells was a product of the biological processing of a protein called the amyloid precursor protein or APP (1, 2). APP, like many other proteins in the body, goes through a modification step called post-translational processing after it is synthesized by the ribosomes. During post-translational processing, APP is cleaved into smaller fragments, or peptides, by proteins called enzymes. When the two enzymes named a and g secretase make excisions on APP, a harmless fragment, p3, is produced (3). However, if APP is cut by the b and g secretases, then fragments of either 40 or 42 amino acids (the building blocks of proteins) result and are released from the cell (4). The 42 amino acid long fragment, named the amyloid beta peptide , is prone to associate with other amyloid beta peptides and has been deemed responsible for the formation of plaques in Alzheimer's patients.