Increased vulnerability of hippocampal neurons from presenilin-1 mutant knock-in mice to amyloid beta-peptide toxicity: central roles of superoxide production and caspase activation.
Many cases of early-onset inherited Alzheimer's disease (AD) are caused by mutations in the presenilin-1 (PS1) gene. Overexpression of PS1 mutations in cultured PC12 cells increases their vulnerability to apoptosis-induced trophic factor withdrawal and oxidative insults. We now report that primary hippocampal neurons from PS1 mutant knock-in mice, which express the human PS1M146V mutation at normal levels, exhibit increased vulnerability to amyloid beta-peptide toxicity. The endangering action of mutant PS1 was associated with increased superoxide production, mitochondrial membrane depolarization, and caspase activation. The peroxynitrite-scavenging antioxidant uric acid and the caspase inhibitor benzyloxycarbonyl-Val-Ala-Asp-fluoromethyl ketone protected hippocampal neurons expressing mutant PS1 against cell death induced by amyloid beta-peptide. Increased oxidative stress may contribute to the pathogenic action of PS1 mutations, and antioxidants may counteract the adverse property of such AD-linked mutations.
Guo
Q
Q
Sanders-Brown Research Center on Aging and Department of Anatomy and Neurobiology, University of Kentucky, Lexington 40536-0230, USA.
Sebastian
L
L
Sopher
B L
BL
Miller
M W
MW
Ware
C B
CB
Martin
G M
GM
Mattson
M P
MP
D000544:Alzheimer Disease / Q000235:genetics; D016229:Amyloid beta-Peptides / Q000502:physiology* / Q000633:toxicity; D000818:Animals; D020169:Caspases / Q000378:metabolism*; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D004789:Enzyme Activation; D006624:Hippocampus / Q000166:cytology* / Q000187:drug effects; D006801:Humans; D007150:Immunohistochemistry; D015227:Lipid Peroxidation / Q000187:drug effects / Q000502:physiology; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D018345:Mice, Knockout; D009154:Mutation; D009474:Neurons / Q000187:drug effects / Q000378:metabolism*; D053764:Presenilin-1; D017382:Reactive Oxygen Species / Q000378:metabolism; D013481:Superoxides / Q000378:metabolism*
D016229:Amyloid beta-Peptides; D008565:Membrane Proteins; C508853:PSEN1 protein, human; D053764:Presenilin-1; D017382:Reactive Oxygen Species; D013481:Superoxides; D020169:Caspases