Endosomal-Lysosomal Cholesterol Sequestration by U18666A Differentially Regulates Amyloid Precursor Protein (APP) Metabolism in Normal and APP-Overexpressing Cells
| Autor: | Robert J. Andrew, G. Phukan, Mahua Maulik, M Stahn, J. Chung, Amany Mohamed, Satyabrata Kar, Gopal Thinakaran, E Posse de Chaves, D. Vergote |
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| Rok vydání: | 2017 |
| Předmět: |
0301 basic medicine
Endosome Mutant Endosomes 03 medical and health sciences chemistry.chemical_compound 0302 clinical medicine Alzheimer Disease mental disorders Extracellular Amyloid precursor protein Aspartic Acid Endopeptidases Humans Molecular Biology Lipid raft Cells Cultured Amyloid beta-Peptides biology Cholesterol Autophagy Cell Biology Cell biology 030104 developmental biology chemistry biology.protein Androstenes Amyloid Precursor Protein Secretases Lysosomes 030217 neurology & neurosurgery Fetal bovine serum Research Article |
| Zdroj: | Molecular and cellular biology. 38(11) |
| ISSN: | 1098-5549 |
| Popis: | Amyloid β (Aβ) peptide, derived from amyloid precursor protein (APP), plays a critical role in the development of Alzheimer's disease. Current evidence indicates that altered levels or subcellular distribution of cholesterol can regulate Aβ production and clearance, but it remains unclear how cholesterol sequestration within the endosomal-lysosomal (EL) system can influence APP metabolism. Thus, we evaluated the effects of U18666A, which triggers cholesterol redistribution within the EL system, on mouse N2a cells expressing different levels of APP in the presence or absence of extracellular cholesterol and lipids provided by fetal bovine serum (FBS). Our results reveal that U18666A and FBS differentially increase the levels of APP and its cleaved products, the α-, β-, and η-C-terminal fragments, in N2a cells expressing normal levels of mouse APP (N2awt), higher levels of human wild-type APP (APPwt), or "Swedish" mutant APP (APPsw). The cellular levels of Aβ1-40/Aβ1-42 were markedly increased in U18666A-treated APPwt and APPsw cells. Our studies further demonstrate that APP and its cleaved products are partly accumulated in the lysosomes, possibly due to decreased clearance. Finally, we show that autophagy inhibition plays a role in mediating U18666A effects. Collectively, these results suggest that altered levels and distribution of cholesterol and lipids can differentially regulate APP metabolism depending on the nature of APP expression. |
| Databáze: | OpenAIRE |
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