Gamma-secretase as a pharmacological target in Alzheimer disease research: when, why and how?

Alzheimer disease (AD) is characterized by excessive deposition of amyloid beta-peptides (Abeta peptides) in the form of senile plaques as well as neurofibrillary tangles (NFTs) in the brain. In the amyloidogenic pathway, the amyloid-beta precursor protein (APP) is cleaved by beta-secretase first, followed by gamma-secretase cleavage producing therefore Abeta. This review summarizes the recent findings in the AD field and focuses on the different gamma-secretase inhibitors that have been developed as a therapeutic approach toward AD.