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Factor VIIa/tissue factor (FVIIa/TF) interaction has been reported to induce intracellular signalling in cells constitutively expressing TF, independently of downstream activation of the coagulation cascade. It is unknown, however, whether binding of FVII to its cofactor TF alters the gene expression profile in cells which inducible express TF under inflammatory conditions. To address this issue, gene expression patterns in cultured LPS-stimulated monocyte-derived macrophages with or without exposure to FVIIa were compared by cDNA macro-array analysis. Of the 1176 genes examined on the array, a small set of six genes (IL-6, IL-8,TNF-a, GRO-beta alpha-thymosin, cathepsin H) were consistently up-regulated and one gene suppressed (alpha-antitrypsin) in response to FVIIa in activated monocyte-derived macrophages. Among the seven genes identified by array analysis, five genes were finally confirmed by real-time RT-PCR. Interestingly, all of these genes differentially regulated in response to FVIIa (GRO-beta, IL-6, IL-8, TNF-alpha and alpha-antitrypsin) are critical in inflammation. The changes in gene expression were reflected by corresponding changes in the protein concentrations of IL-6 and IL-8 as demonstrated by ELISA. Active site-inhibited FVIIa had no effect on gene expression indicating that FVIIa-induced gene alteration is dependent on the proteolytic activity of FVIIa. The FVIIa-induced alterations in gene expression were found to be TF-dependent but independent of downstream coagulation proteins like thrombin and FXa. In summary, this study demonstrates that binding of FVIIa to its cofactor TF enhances restricted pro-inflammatory genes in activated monocyte-derived macrophages. By up-regulation of chemokines critical for leukocyte recruitment, FVIIa/TF interaction on activated monocyte-derived macrophages could be relevant to prepare monocytes/macrophages for extravasation and may represent a novel amplification loop of leukocyte recruitment.

Ca(2+)-activated K(+) channels with large conductance (BK(Ca)) have been shown to play an important role in the regulation of vascular tone. We examined the role of the p42/p44 MAP-kinase (p42/p44(MAPK)) on nitric oxide (NO) production in human endothelial cells induced by the BK(Ca)-opener NS1619. Using DiBAC-fluorescence imaging a concentration-dependent (2.5-12.5 microM) hyperpolarization induced by NS1619 was observed. A significant increase of intracellular Ca(2+)-concentration by NS1619 was seen using Fura-2-fluorescence-imaging, which was blocked by 2-APB, or reduction of extracellular Ca(2+) (n=30; p<0.05). A cGMP-radioimmunoassay was used to examine NO synthesis. NS1619 significantly increased cGMP levels which was inhibited by LNMMA, iberiotoxin, BAPTA, 2-APB, reduction of extracellular Ca(2+), PD 98059, or U0126 (cGMP (pmol/mg protein): NS1619 3.25 +/- 0.85; NS1619 + L-NMMA 0.86 +/- 0.02; NS1619 + iberiotoxin 0.99 +/- 0.09; NS1619 + BAPTA 0.93 +/- 0.29; NS1619 + 2-APB 0.99 +/- 0.31; NS1619 + Ca(2+)-reduction 1.17 +/- 0.06; NS1619 + PD98059 1.06 +/- 0.49; NS1619 + U0126 1.10 +/- 0.24; n=10; p<0.05). The phosphorylation of eNOS and p42/p44(MAPK) was examined by immunocytochemistry. Phosphorylation of p42/p44(MAPK) was significantly increased after 10 minutes of NS1619 stimulation, whereas eNOS phosphorylation was not changed over a period of 1 to 30 minutes. NS1619-induced hyperpolarization was not affected by treatment with PD 98059 or U0126. Additionally, NS1619 inhibited endothelial proliferation involving a NO-dependent mechanism. Our data demonstrate that NS1619 causes a transmembrane Ca(2+)-influx leading to an increased NO production involving p42/p44(MAPK). This rise of NO formation is responsible for the NS1619 induced reduction of endothelial cell growth.

The association between use of oral contraceptives (OCs) and increased risk of thromboembolic disease has been firmly established. This risk increases when use of OCs is combined with cigarette smoking. The cellular mechanism favoring an hypercoagulable state under these behaviours is not known. Circulating monocytes are potent activators of the coagulation cascade through their ability to synthesize procoagulant tissue factor (TF). In the present study we report that monocyte TF expression is increased in women who use OCs and smoke. We studied monocyte TF expression in 4 groups of healthy pre-menopausal women (n = 15 each): (1) non-smoking OC non-users, (2) nonsmoking current OC users, (3) smoking OC non-users and (4) smoking OC users. TF expression was assessed on both mRNA and protein levels in unstimulated and LPS-stimulated cells. Transcriptional activation of the TF gene was assessed by analysis of the transcription factor NF-kappaB and its inhibitor molecule IkappaBalpha. Monocyte TF generation was significantly higher in OC users than in women who did not use OCs. Enhanced monocyte TF generation was also observed in smoking women when compared to non-smokers. Strongest monocyte TF expression occurred in women with combined smoking and use of OCs. The enhanced TF expression in monocytes from women using OCs or smoking was based on an increased TF gene transcription following activation of NF-kappaB. Experiments on cultured monocytes/macrophages demonstrated enhanced IkappaBalpha degradation in the presence of estradiol, suggesting that a direct hormone effect is responsible for the observed increase in monocyte TF expression. This study demonstrates that use of OCs and smoking is associated with an increase in monocyte TF expression in pre-menopausal women. Aberrant TF expression by blood monocytes may favour intravascular clotting activation in women with OC therapy. The further enhancement of TF activity observed in women who smoke and use OCs may explain the synergistic effect of smoking on risk of thromboembolic events associated with contraceptive use.

Background: Disturbances in fibrinolytic activity, such as increase in plasminogen activator inhibitor (PAI) activity, have been linked with an increased risk for coronary artery disease (CAD) and myocardial infarction (MI). Since 4G4G homozygotes of an insertion/deletion (4G/5G) gene variation in the promoter of PAI-I have been shown to have increased levels of PAI-I, we analysed the relation of this gene polymorphism to CAD and MI in a population of 2565 participants who underwent coronary angiography for diagnostic purposes., Results: In the total sample, the PAI-I 4G/4G genotype was associated with the presence, but not with the extent of CAD. However, in a subgroup of former and present smokers (n = 1782) or of individuals with a BMI above the mean value of 26.9 kg x m(-2) (n = 1269), the PAI-I 4G4G genotype was not only associated with the presence, but also with the extent of CAD, defined either by the number of diseased vessels or by the CHD score according to Gensini. This observation also applied to other high-risk groups of individuals with high BMI and hypertension (n = 869), of subjects with high fibrinogen plasma levels (>3.53 g x l(-1), mean value) and hypertension (n = 599) and of former and present smokers with high fibrinogen and hypertension (n = 452). An association of the gene variation with MI was not detected., Conclusions: The present data indicate that the 4G/4G genotype of the PAI-I gene polymorphism is an independent risk factor for coronary artery disease and that the additional presence of major cardiovascular risk factors accelerates the risk for this disease.

Background: G to A transitions at nucleotide position 20210 of the factor II (Fll) gene and at 1691 of the factor V (FV) gene have been shown to be associated with an increased risk of venous thrombosis. Since it is still unclear whether both gene variations are also related to an increased risk of coronary heart disease (CHD), we studied the relation of both gene variations to coronary artery disease (CAD) and myocardial infarction (MI) in a sample of 2210 male individuals whose coronary anatomy were defined by coronary angiography., Results: In the total sample, the FII G20210A gene variation was not associated with the presence or the extent of CAD, the latter defined either by the degree of vessel disease or by a CHD score according to Gensini. However, individuals with unfavourable lipid profiles showed pronounced differences in CHD scores between GA heterozygotes and GG homozygotes: this observation applied in particular to younger patients (<62 years; mean age of total sample) who simultaneously had low apoAI/apoB ratios (< 1.19, mean value) and high Lp(a) plasma levels (>28 mg/dl; mean value). In addition, in subjects without acetylsalicylic acid treatment GA heterozygotes had clearly higher CHD scores than AA genotypes. Further restriction to smokers, to subjects with high fibrinogen plasma levels (>3.47 g/l; mean value) or to patients with high glucose concentrations (>112 mg/dl; mean value) tended to increase the difference in CHD score between FII G20210A genotypes. An association of the FII G20210A gene variation with non-fatal MI was not observed. In the total sample and in high and low risk subpopulations, an association of the FV G1691A gene variation was not detected neither with presence and extent of CAD or with nonfatal MI., Conclusion: The importance of the factor II G20210A gene variation for CHD may be restricted to individuals with major cardiovascular risk factors. In addition, the present study did not strengthen the hypothesis of the factor V G 1691 A transition as a risk factor of coronary heart disease neither in the total sample nor in subgroups of individuals who were at high or low risk of CHD.

Background: The platelet membrane glycoprotein IIb/IIIa functions as a receptor for fibrinogen and von Willebrand factor during platelet aggregation. In a small case-control study, evidence has been presented that the PlA2 allele of the platelet glycoprotein GPIIIa PlA/A2 gene polymorphism might be an independent risk factor for acute myocardial infarction (MI)., Methods and Results: We explored the association of the PlA1A2 to the severity of coronary artery disease (CAD), as assessed angiographically in 2252 male individuals, and to myocardial infarction (MI). The severity of coronary heart disease (CHD) was also estimated by calculating a CHD score according to Gensini. The PlA genotype was determined by allele specific restriction digestion. Relation of the PlA2 allele to CAD: In the total population, the frequency of the PlA2 allele was not associated to the presence or to the extent of CAD. Also the CHD scores of PlA1/PlA2 genotypes were essentially the same. However, after exclusion of individuals with high BMI (> or =26.9 kg/m2) and/or low apoAI (< 1.43 g/l) PlA2PlA2 carriers had clearly higher CHD scores than PlA1PlA1 genotypes: PlA1PlA2 heterozygotes had intermediate values (p <0.05). After division of the study population into one group of individuals without any angiographic signs of CAD (CHD score = 0) and into another group of patients with severe CAD (CHD score (> or = 120), a strong association of the PlA2 allele with severe CAD was also found in the same low risk groups: e.g. exclusion of persons with high BMI and low apoAI resulted in an Odds ratio of 5.37 (1.46-19.7) (p <0.02). Relation of the PlA2 allele to MI: No association was found between PlA1/PlA2 genotypes and risk of MI neither in the total population nor in low risk subgroups., Conclusions: Whereas no difference in the distribution of allele and genotype frequencies between controls and survivors of MI could be detected, the PlA2 allele is associated with CHD in low risk patients.

Background: Fibrinogen has been demonstrated to be an independent risk factor of cardiovascular disease. The absence of the HaeIII cutting site (H2 allele) of an H1/H2 gene variation in the promoter region of the beta fibrinogen gene was associated with increased levels of fibrinogen., Methods and Results: In the present study, the effects of the H1/H2 gene variation not only on plasma fibrinogen concentrations but also on coronary artery disease (CAD) and myocardial infarction (MI) were investigated in 923 individuals who underwent coronary angiography for diagnostic purposes. Relation of the H1/H2 genotype to fibrinogen plasma levels: A strong association was observed between the H1/H2 gene variation and fibrinogen levels. The differences in fibrinogen plasma levels between H2H2 and H1H1 homozygotes were almost threefold more pronounced within subjects with clinical chemical signs of an acute phase reaction (CRP > or = 7.5 mg/l) than within a subgroup of subjects without these signs (CRP < 7.5 mg/l) (median of CRP distribution: 7.5 mg/l). In 207 patients who underwent aortocoronary bypass surgery plasma fibrinogen levels were almost identical directly after surgery. Two days after operation fibrinogen increased to clearly higher levels in H2H2 homozygotes than in H1H2 and H1H1 genotypes, whereas almost the same maximal increases in fibrinogen concentrations were reached 3-4 days after surgery in all individuals. Relation of the H1/H2 genotype to CAD and MI. Whereas in the total population the plasma fibrinogen concentrations were strongly associated with smoking, CAD and MI, an association of the H1/H2 gene variation to CAD and MI was not detected. However, mean age at first MI of H2H2 individuals (62.9 years) was clearly higher than of H1H2 genotypes (56.9 years) and of H1H1 subjects (56.4 years). In addition, in a subgroup of individuals with a higher risk of MI by either high apoB and/or low apoA1 plasma levels the portion of MI patients was clearly smaller within H2H2 homozygotes than within H1H2 or H1H1 genotypes, although-also in these high risk groups-mean age at first MI of H2H2 individuals were higher than of the other two genotypes., Conclusions: Obviously, the H2 allele of the fibrinogen H1/H2 genotype does not only influence basal fibrinogen concentrations, but particularly also the extent of fibrinogen level increase during acute phase reaction. Whereas the fibrinogen plasma level is positively associated with coronary artery disease and myocardial infarction, the H2 allele-although exhibiting an association with elevated fibrinogen levels-was not positively associated with CAD and MI.