We previously reported that oxidized low density lipoprotein (ox-LDL) induc
ed apoptosis in vascular smooth muscle cells (VSMCs). However, the transcri
ption factors important for apoptotic signalling have been little clarified
. We investigated the involvement of nuclear factor-kappa B (NF-kappa B), b
y which apoptotic signalling is reported to be mediated, in ox-LDL-induced
apoptosis. The effect of ox-LDL on the transcriptional factor NF-kappa B ac
tivation was investigated by electrophoretic mobility shift assay (EMSA), O
x-LDL caused NF-kappa B activation in VSMCs. Next, we investigated the effe
ct on ox-LDL-induced apoptosis by introduction of synthetic double-stranded
DNA with high affinity for NF kappa B in vitro as "decoy" cis elements tha
t bind the transcriptional factor. Treatment by transfection of NF-kappa B
decoy oligodeoxynucleotides (ODN), but not scramble ones, blunted the activ
ation of NF-kappa B by ox-LDL and caused a significant further induction of
ox-LDL-induced apoptosis. Results indicate that the activation of NF-kappa
B prevents excessive apoptosis by ox-LDL in VSMCs. (C) 2000 Elsevier Scien
ce Inc. All rights reserved.