Amyloid beta-peptide activates nuclear factor-kappaB through an N-methyl-D-aspartate signaling pathway in cultured cerebellar cells.
Amyloid beta-peptide (A beta) likely causes functional alterations in neurons well prior to their death. Nuclear factor-kappaB (NF-kappaB), a transcription factor that is known to play important roles in cell survival and apoptosis, has been shown to be modulated by A beta in neurons and glia, but the mechanism is unknown. Because A beta has also been shown to enhance activation of N-methyl-D-aspartate (NMDA) receptors, we investigated the role of NMDA receptor-mediated intracellular signaling pathways in A beta-induced NF-kappaB activation in primary cultured rat cerebellar cells. Cells were treated with different concentrations of A beta1-40 (1 or 2 microM) for different periods (6, 12, or 24 hr). MK-801 (NMDA antagonist), manumycin A and FTase inhibitor 1 (farnesyltransferase inhibitors), PP1 (Src-family tyrosine kinase inhibitor), PD98059 [mitogen-activated protein kinase (MAPK) inhibitor], and LY294002 [phosphatidylinositol 3-kinase (PI3-k) inhibitor] were added 20 min before A beta treatment of the cells. A beta induced a time- and concentration-dependent activation of NF-kappaB (1 microM, 12 hr); both p50/p65 and p50/p50 NF-kappaB dimers were involved. This activation was abolished by MK-801 and attenuated by manumycin A, FTase inhibitor 1, PP1, PD98059, and LY294002. A beta at 1 microM increased the expression of inhibitory protein I kappaB, brain-derived neurotrophic factor, inducible nitric oxide synthase, tumor necrosis factor-alpha, and interleukin-1 beta as shown by RT-PCR assays. Collectively, these findings suggest that A beta activates NF-kappaB by an NMDA-Src-Ras-like protein through MAPK and PI3-k pathways in cultured cerebellar cells. This pathway may mediate an adaptive, neuroprotective response to A beta.
Kawamoto
E M
EM
Department of Pharmacology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil.
Lepsch
L B
LB
Boaventura
M F C
MF
Munhoz
C D
CD
Lima
L S
LS
Yshii
L M
LM
Avellar
M C W
MC
Curi
R
R
Mattson
M P
MP
Scavone
C
C
D016229:Amyloid beta-Peptides / Q000378:metabolism*; D000818:Animals; D002478:Cells, Cultured; D002531:Cerebellum / Q000187:drug effects / Q000378:metabolism; D016291:Dizocilpine Maleate / Q000494:pharmacology; D024202:Electrophoretic Mobility Shift Assay; D004789:Enzyme Activation / Q000187:drug effects / Q000502:physiology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology; D005455:Fluorescent Antibody Technique; D015870:Gene Expression / Q000187:drug effects; D015151:Immunoblotting; D020928:Mitogen-Activated Protein Kinases / Q000187:drug effects / Q000378:metabolism; D016202:N-Methylaspartate / Q000187:drug effects / Q000378:metabolism*; D016328:NF-kappa B / Q000378:metabolism*; D009474:Neurons / Q000187:drug effects / Q000378:metabolism*; D019869:Phosphatidylinositol 3-Kinases / Q000187:drug effects / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology*
D016229:Amyloid beta-Peptides; D004791:Enzyme Inhibitors; D018691:Excitatory Amino Acid Antagonists; D016328:NF-kappa B; D016202:N-Methylaspartate; D016291:Dizocilpine Maleate; D019869:Phosphatidylinositol 3-Kinases; D020928:Mitogen-Activated Protein Kinases