Abstract
Tumor necrosis factor type I receptor (TNFRI), a death receptor, mediates apoptosis and plays a crucial role in the interaction between the nervous and immune systems. A direct link between death receptor activation and signal cascade-mediated neuron death in brains with neurodegenerative disorders remains inconclusive. Here, we show that amyloid-beta protein (Abeta), a major component of plaques in the Alzheimer's diseased brain, induces neuronal apoptosis through TNFRI by using primary neurons overexpressing TNFRI by viral infection or neurons from TNFRI knock-out mice. This was mediated via alteration of apoptotic protease-activating factor (Apaf-1) expression that in turn induced activation of nuclear factor kappaB (NF-kappaB). Abeta-induced neuronal apoptosis was reduced with lower Apaf-1 expression, and little NF-kappaB activation was found in the neurons with mutated Apaf-1 or a deletion of TNFRI compared with the cells from wild-type (WT) mice. Our studies suggest a novel neuronal response of Abeta, which occurs through a TNF receptor signaling cascade and a caspase-dependent death pathway.
Publication types
-
Research Support, Non-U.S. Gov't
MeSH terms
-
Active Transport, Cell Nucleus / drug effects
-
Active Transport, Cell Nucleus / physiology
-
Amyloid beta-Peptides / toxicity*
-
Animals
-
Antigens, CD / genetics*
-
Antigens, CD / metabolism
-
Apoptosis / drug effects
-
Apoptosis / genetics
-
Apoptotic Protease-Activating Factor 1
-
Cell Nucleus / metabolism
-
Cells, Cultured
-
Cytoplasm / metabolism
-
Gene Targeting
-
Genes, Reporter
-
Hippocampus / cytology
-
Humans
-
Mice
-
Mice, Inbred C57BL
-
Mice, Knockout
-
NF-kappa B / metabolism
-
Neurons / drug effects*
-
Neurons / metabolism*
-
Peptide Fragments / toxicity*
-
Proteins / genetics
-
Proteins / metabolism
-
RNA, Messenger / metabolism
-
Receptors, Tumor Necrosis Factor / genetics*
-
Receptors, Tumor Necrosis Factor / metabolism
-
Receptors, Tumor Necrosis Factor, Type I
-
Signal Transduction / physiology*
-
Transfection
-
Up-Regulation / drug effects
Substances
-
APAF1 protein, human
-
Amyloid beta-Peptides
-
Antigens, CD
-
Apaf1 protein, mouse
-
Apoptotic Protease-Activating Factor 1
-
NF-kappa B
-
Peptide Fragments
-
Proteins
-
RNA, Messenger
-
Receptors, Tumor Necrosis Factor
-
Receptors, Tumor Necrosis Factor, Type I
-
amyloid beta-protein (1-40)