Cy. Han et al., Role of endocytosis in the transactivation of nuclear factor-kappa B by oxidized low-density lipoprotein, BIOCHEM J, 350, 2000, pp. 829-837
Oxidized low-density lipoprotein (oxLDL) has been shown to modulate transac
tivation by the peroxisome proliferator-activated receptor (PPAR)-gamma and
by nuclear factor-kappa B (NF-kappa B). In the present study, the oxLDL si
gnalling pathways involved in NF-kappa B transactivation were investigated
by utilizing a reporter construct driven by three upstream NF-kappa B bindi
ng sites, and Various pharmacological inhibitors. OxLDL and its constituent
lysophophatidylcholine (lysoPC) induced a rapid and transient increase in
intracellular calcium and stimulated NF-kappa B transactivation in resting
RAW264.7 macrophage cells in an oxidation-dependent manner. NF-kappa B acti
vation by oxLDL or lysoPC was inhibited by inhibitors of protein kinase C o
r by a chelator of intracellular calcium. Tyrosine kinase or phosphatidylin
ositol 3-kinase inhibitors did not block NF-kappa B transactivation.