Identification of the Process of Amyloid -Peptide Degrading Catabolism in the Brain Laboratory for Proteolytic Neuroscience Dr. Takaomi C. Saido, Head of the Laboratory for Proteolytic Neuroscience and colleagues have successfully clarified the degrading mechanism of amyloid -peptide in the brain through the application of a new experimental paradigm that uses radioisotopes for the analysis of amyloid -peptide, a key protein for the research of brain aging. Primarily responsible for the aging of the brain that leads to Alzheimer's disease is believed to be the deposition of amyloid -peptide. The amyloid ｧ-peptide is a sort of ﾒdaily garbage in vivo,ﾓ which is constantly anabolized and catabolized in a normal brain. While much of the process of its anabolism has been extensively studied in the last decade, its catabolic process remains largely unclarified. This study found that a protein-degrading enzyme called neutral endopeptidase plays a key role in the catabolic process and that a suppression of its action leads to the deposition of amyloid -peptide. One achievement of this study is the discovery of a clue to the clarification of the aging mechanism of the brain. This research has also paved the way for a possible prevention and remedy of dementia by regulating brain aging through the manipulation of the catabolic process. Amyloid -Peptide Degrading Catabolic Pathway magnified scene by clicking image Iwata, N., Tsubuki, S., Takaki, Y., Watanabe, K., Sekiguchi, M., Hosoki, E., Kawashima-Morishima, M., Jun Lee, H., Hama, E., Sekine-Aizawa, Y., Saido, T. C. Identification of the major Aβ1-42-degrading catabolic pathway in brain parenchyma: Suppression leads to biochemical and pathological deposition Nature Medicine, Vol. 6, No. 2, pp143-150, February (2000)