BACKGROUNDFractalkine is an important chemokine mediating local monocyte accumulation and inflammatory reactions in the vascular wall. Aspirin inhibits inflammatory cytokine expression closely related to atherosclerosis through the way independent of platelet and cyclooxygenase (COX). There has been no report about the effect of aspirin on fractalkine expression. We aimed to determine the fractalkine expression in human umbilical vein endothelial cell (HUVEC) stimulated by tumor necrosis factor (TNF)-alpha and the effect of aspirin intervention.

METHODSSix of 8 HUVEC groups received either different concentrations of aspirin (0.02, 0.2, 1.0, 5.0 mmol/L) or 40 micromol/L pyrrolidinecarbodithioc acid (PDTC) or 0.5 micromol/L NS-398. The other two groups were negative control and positive control (TNF-alpha-stimulated). After being incubated for 24 hours, cells of the 8 groups except the negative control one were stimulated with TNF-alpha (4 ng/ml) for another 24 hours. After that, the cells were collected for RNA isolation and protein extraction.

RESULTSBoth mRNA and protein expressions of fractalkine in HUVEC were upregulated by 4 ng/ml TNF-alpha stimulation. Aspirin inhibited fractalkine expression in a dose-dependent manner at mRNA and protein levels. Nuclear factor-kappa B inhibitor, PDTC, effectively decreased the fractalkine expression. Fractalkine expression was not influenced by COX-2 selective inhibitor NS-398. COX-1 protein expression was not changed by either TNF-alpha stimulation or aspirin, PDTC, NS-398 intervention. Both mRNA and protein expression of COX-2 in HUVEC were upregulated by 4 ng/ml TNF-alpha stimulation. Aspirin decreased COX-2 expression in a dose-dependent manner at mRNA and protein levels.

CONCLUSIONSTNF-alpha-stimulated fractalkine expression is suppressed by aspirin in a dose-dependent manner through the nuclear factor-kappa B p65 pathway.