β‐secretase‐cleaved amyloid precursor protein in Alzheimer brain: a morphologic study

• Published in: Journal of cellular and molecular medicine Vol. 8; no. 1; pp. 127 - 134
• Main Authors: Sennvik, Kristina, Bogdanovic, N., Volkmann, Inga, Fastbom, J., Benedikz, E.
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01.01.2004; John Wiley & Sons, Inc
• Subjects: Alzheimer Disease - metabolism; Alzheimer's disease; Amyloid beta-Protein Precursor - metabolism; Amyloid precursor protein; Amyloid Precursor Protein Secretases; Aspartic Acid Endopeptidases - metabolism; Astrocytes; Astrocytes - metabolism; Axonal transport; Axons; Axons - metabolism; Blood vessels; Brain - pathology; Endopeptidases; Humans; Immunohistochemistry; Localization; Medicin och hälsovetenskap; Microscopy, Fluorescence; Neurodegenerative diseases; Occipital lobe; Proteolysis; Secretase; Senile plaques; Substantia alba; Substantia grisea; β-Amyloid
• ISSN: 1582-1838; 1582-4934; 1582-4934
• DOI: 10.1111/j.1582-4934.2004.tb00267.x

β‐amyloid (Aβ) is the main constituent of senile plaques seen in Alzheimer's disease. Aβ is derived from the amyloid precursor protein (APP) via proteolytic cleavage by proteases β‐ and β‐secretase. In this study, we examined content and localization of β‐secretase‐cleaved APP (β‐sAPP) in brain tissue sections from the frontal, temporal and occipital lobe. Strong granular β‐sAPP staining was found throughout the gray matter of all three areas, while white matter staining was considerably weaker. β‐sAPP was found to be localized in astrocytes and in axons. We found the β‐sAPP immunostaining to be stronger and more extensive in gray matter in Alzheimer disease (AD) cases than controls. The axonal β‐sAPP staining was patchy and unevenly distributed for the AD cases, indicating impaired axonal transport. β‐sAPP was also found surrounding senile plaques and cerebral blood vessels. The results presented here show altered β‐sAPP staining in the AD brain, suggestive of abnormal processing and transport of APP.