Elevated vulnerability to oxidative stress-induced cell death and activation of caspase-3 by the Swedish amyloid precursor protein mutation.
The Swedish double mutation (KM670/671NL) of amyloid precursor protein (APPsw) is associated with early-onset familial Alzheimer's disease (FAD) and results in from three- to sixfold increased beta-amyloid production. The goal of the present study was to elucidate the effects of APPsw on mechanisms of apoptotic cell death. Therefore, PC12 cells were stably transfected with human APPsw. Here we report that the vulnerability of APPsw-bearing PC12 cells to undergo apoptotic cell death was significantly enhanced after exposure to hydrogen peroxide compared to human wild-type APP-bearing cells, empty vector-transfected cells, and parent untransfected cells. In addition, we have analyzed the potential influence of several mechanisms that can interfere with the execution of the apoptotic cell death program: the inhibition of cell death by the use of caspase inhibitors and the reduction of oxidative stress by the use of (+/-)-alpha-tocopherol (vitamin E). Interestingly, oxidative stress-induced cell death was significantly attenuated in APPsw PC12 cells by pretreatment with caspase-3 inhibitors but not with caspase-1 inhibitors. In parallel, caspase-3 activity was markedly elevated in APPsw PC12 after stimulation with hydrogen peroxide for 6 hr, whereas caspase-1 activity was unaltered. In addition, oxidative stress-induced cell death could be reduced after pretreatment of APPsw cells with (+/-)-alpha-tocopherol. The protective potency of (+/-)-alpha-tocopherol was even greater than that of caspase-3 inhibitors. Our findings further emphasize the role of mutations in the amyloid precursor protein in apoptotic cell death and may provide the fundamental basis for further efforts to elucidate the underlying processes caused by FAD-related mutations.
Eckert
A
A
Department of Pharmacology, Biocenter, University of Frankfurt, Frankfurt, Germany. A.Eckert@em.uni-frankfurt.de
Steiner
B
B
Marques
C
C
Leutz
S
S
Romig
H
H
Haass
C
C
Müller
W E
WE
D000544:Alzheimer Disease / Q000453:epidemiology / Q000235:genetics*; D000590:Amino Acid Chloromethyl Ketones / Q000494:pharmacology; D053829:Amyloid Precursor Protein Secretases; D016564:Amyloid beta-Protein Precursor / Q000235:genetics* / Q000502:physiology; D000813:Anilides / Q000494:pharmacology; D000818:Animals; D000975:Antioxidants / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects; D016282:Aspartic Acid Endopeptidases / Q000378:metabolism; D053148:Caspase 3; D020169:Caspases / Q000378:metabolism*; D015853:Cysteine Proteinase Inhibitors / Q000494:pharmacology; D010450:Endopeptidases; D004789:Enzyme Activation; D006801:Humans; D006861:Hydrogen Peroxide / Q000633:toxicity; D009154:Mutation; D009419:Nerve Tissue Proteins / Q000378:metabolism*; D009842:Oligopeptides / Q000494:pharmacology; D018384:Oxidative Stress; D016716:PC12 Cells; D010455:Peptides; D011506:Proteins / Q000494:pharmacology; D051381:Rats; D013548:Sweden / Q000453:epidemiology; D014162:Transfection; D014810:Vitamin E / Q000494:pharmacology
C423942:Ac-AAVALLPAVLLALLAPYVAD-CHO; D000590:Amino Acid Chloromethyl Ketones; D016564:Amyloid beta-Protein Precursor; D000813:Anilides; D000975:Antioxidants; D015853:Cysteine Proteinase Inhibitors; C098738:N-acetyl-tyrosyl-valyl-alanyl-aspartyl chloromethyl ketone; D009419:Nerve Tissue Proteins; D009842:Oligopeptides; D010455:Peptides; D011506:Proteins; C430227:acetyl-AAVALLPAVLLALLAP-DEVD-CHO; C430230:acetyl-aspartyl-glutamyl-valyl-aspartic acid p-nitroanilide; C430228:acetyl-aspartyl-glutamyl-valyl-lysine chloromethyl ketone; C430229:acetyl-tyrosyl-valyl-alanyl-aspartic acid p-nitroanilide; C096713:benzyloxycarbonylvalyl-alanyl-aspartyl fluoromethyl ketone; D014810:Vitamin E; D006861:Hydrogen Peroxide; D053829:Amyloid Precursor Protein Secretases; D010450:Endopeptidases; C505407:CASP3 protein, human; C505410:Casp3 protein, rat; D053148:Caspase 3; D020169:Caspases; D016282:Aspartic Acid Endopeptidases; C509284:BACE2 protein, human; C509280:BACE1 protein, human; C509281:Bace1 protein, rat