Experimental Alzheimer Drugs Targeting Beta- Amyloid and the “Amyloid Hypothesis”

What is beta-amyloid? Beta-amyloid is a small piece of a larger protein called “amyloid precursor protein” (APP). Although scientists have not yet determined APP’s normal function, they have learned a great deal about how it appears to work. In its complete form, APP extends from the inside to the outside of brain cells by passing through a fatty membrane around the cell. When APP is “activated” to do its normal job, it is cut by other proteins into smaller sections that stay inside and outside cells. There are several different ways APP can be cut. Under some circumstances, one of the pieces produced is beta-amyloid.