The normal function of the amyloidal precursor protein or APP clarified It has been known for several years that APP is relevant in Alzheimer's disease. APP is the precursor of the amyloidal-â protein that causes the typical 'plaques' in the brains of patients. The normal function of APP was, however, not known. Maarten Leyssen and his colleagues have indicated that APP stimulates the development of nerve paths. Intact nerve paths are essential for the proper functioning of the brain. These connections can be damaged after traumatic brain damage resulting in the improper functioning of the brain. APP is responsible for stimulating the development of new nerve paths.
APP and Alzheimer's disease
These results also aid better understanding of certain aspects of Alzheimer's disease, where APP plays a major role. The fruit fly – an ideal model to study the brain's action – indicates that APP increases considerably after brain damage, namely in areas where new nerve paths need to be formed. Because more APP is made, more plaques can develop in the brain, a typical symptom of Alzheimer's disease. For the first time the results of VIB researchers explain the strong link between brain damage and Alzheimer's disease: not only do patients with major brain damage have more chance of developing Alzheimer's disease later on in life, their brains also often show plaques that strongly resemble those of Alzheimer patients.