ABSTRACT
<p><b>BACKGROUND</b>Fractalkine 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.</p><p><b>METHODS</b>Six 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.</p><p><b>RESULTS</b>Both 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.</p><p><b>CONCLUSIONS</b>TNF-alpha-stimulated fractalkine expression is suppressed by aspirin in a dose-dependent manner through the nuclear factor-kappa B p65 pathway.</p>
Subject(s)
Humans , Aspirin , Pharmacology , Blotting, Western , Cell Line , Chemokine CX3CL1 , Genetics , Metabolism , Endothelial Cells , Metabolism , Gene Expression Regulation , Reverse Transcriptase Polymerase Chain Reaction , Tumor Necrosis Factor-alpha , Pharmacology , Umbilical Veins , Cell BiologyABSTRACT
<p><b>OBJECTIVE</b>Coronary arterial plaque rupture and secondary thrombosis are the major pathogenesis of acute coronary syndrome (ACS). Metalloprotease (MMPs) secreted by monocyte/macrophage was the main predisposing factor of the plaque rupture and peroxisome proliferator-activated receptor-gamma (PPAR-gamma) is involved in a variety of inflammatory cytokine gene transcriptional regulations. We explored the possible role of PPAR-gamma in the regulation of MMP-9 and TIMP-1 expressed by peripheral monocyte-derived macrophages (MDMs) from patients with ACS.</p><p><b>METHODS</b>Peripheral blood mononuclear cells were isolated from 48 patients with ACS and 28 healthy controls and stimulated by macrophage colony-stimulating factor (0.1 microg/ml for 24 hours) to form MDMs. MDMs were then incubated under various concentrations of rosiglitazone (0, 1, 10, 20 micromol/L) for 48 hours. The concentrations of MMP-9 and TIMP-1 in the supernatant were measured by enzyme linked immunosorbent assay, and the mRNA expression of PPAR-gamma, MMP-9 by RT-PCR and nuclear factor-kappaB P65 (NF-kappaB P65) expression by immunohistochemistry.</p><p><b>RESULTS</b>PPAR-gamma mRNA expression was significantly lower while NF-kappaB P65 and MMP-9 expression as well as MMP-9 and TIMP-1 concentrations in supernatant were significantly higher in ACS group than those in control group (all P < 0.05). After rosiglitazone intervention, PPAR-gamma mRNA expression was significantly upregulated in both ACS and control groups in a dose-dependent manner. Both the MMP-9 concentration in the supernatant and MMP-9 mRNA expression were reduced post intervention with rosiglitazone in both groups. The TIMP-1 mRNA expression and concentration in supernatant were not affected by rosiglitazone in both groups. Rosiglitazone induced significant downregulation of NF-kappaB P65 expression in both groups.</p><p><b>CONCLUSION</b>Rosiglitazone intervention may downregulate MMP-9 expression by upregulating PPAR-gamma expression, and by downregulating NF-kappaB expression in MDMs isolated from patients with ACS.</p>
Subject(s)
Aged , Female , Humans , Male , Middle Aged , Acute Coronary Syndrome , Blood , Case-Control Studies , Cells, Cultured , Macrophages , Metabolism , Matrix Metalloproteinase 9 , Metabolism , PPAR gamma , Thiazolidinediones , Pharmacology , Tissue Inhibitor of Metalloproteinase-1 , Metabolism , Transcription Factor RelA , Metabolism , Vasodilator Agents , PharmacologyABSTRACT
Background Fractalkine is involved in the impairment of endothelium by mediating inflammatory cell chemotaxis.Aspirin inhibites many kinds of cytokine expression.Objective To investigate the effect of aspirin on tumor necrosis factor ?(TNF-?) stimulated fractalkine expression in human umbilical vein endothelial cells (HUVEC) and its mechanism.Methods HUVEC were grouped as follows:control group;TNF-?-stimu- lated;TNF-?+NS-398;TNF-?+PDTC and TNF plus various concentration of aspirin (0.02,0.2,1.5 mmol/L). The level of mRNA and protein expression of fractalkine and nuclear factor(NF)-kB p65 was determined by RT- PCR and Western blot.Results 1)Fractalkine mRNA and protein level was increased after 4 ?g/L TNF-? stim- ulation in HUVEC(both P