C-reactive protein levels predict systolic heart failure and outcome in patients with first ST-elevation myocardial infarction treated with coronary angioplasty.

INTRODUCTION: There is growing evidence that inflammation plays a pivotal role in the etiology and progression of atherosclerosis. High C-reactive protein (CRP) levels have been associated with high mortality in patients with acute myocardial infarction (AMI). Furthermore, in animal models CRP has been found to significantly increase infarct size. So there is growing evidence that CRP is not only a marker for cardiovascular disease but also might be pathogenic. The aim of our study was to test the hypothesis that peak CRP levels could predict heart failure (HF) in ST-elevation myocardial infarction (STEMI) patients. MATERIAL AND METHODS: Eighty-one consecutive patients with STEMI were prospectively enrolled in the study. C-reactive protein concentrations were measured on admission and after 6, 12, 24, 30, 48, 72 and 96 h. We assessed the association between the elevation of CRP, heart failure and cardiovascular mortality following the first 12 months after STEMI. RESULTS: C-reactive protein levels reached a peak after 48 h. Patients with STEMI and signs of HF showed significantly higher peak CRP levels. We found a positive correlation between maximum CK levels and peak CRP and a negative correlation between left ventricular ejection fraction (EF) and peak CRP. One year total mortality and HF mortality rates were found to be higher in patients with peak CRP > 47.5 mg/l than in those with CRP below that level (p < 0.001). CONCLUSIONS: Peak CRP levels in STEMI patients predict emergence of HF. Peak CRP is also a strong predictor of global and cardiovascular mortality during the following year after STEMI.

Platelet CD40 contributes to enhanced monocyte chemoattractant protein 1 levels in patients with resistant hypertension.

BACKGROUND: Growing evidence shows that inflammation plays a pivotal role in the pathophysiology of essential hypertension (EH). Although it is acknowledged that target organ damage involves an inflammatory response, most work has focused on the role of macrophages. However, recently, platelets were identified as inducing inflammation partly by releasing cytokines. The goal of our study was to evaluate the role of platelets as inflammatory cells in the pathogenesis of EH. METHODS: Thirty-nine patients with EH and 30 healthy normotensive controls have been examined. Expression of platelet CD40 was measured by flow cytometry. Serum levels of monocyte chemoattractant protein 1 (MCP-1) and sCD40L were measured via a multiplexing assay. In in vitro experiments, activated platelets were cocultured with human umbilical vein endothelial cells (HUVEC) in the presence and absence of anti-CD154 antibodies. MCP-1 in the supernatants was measured by EIA. RESULTS: Essential hypertension patients showed significantly enhanced MCP-1 levels with highest levels in EH patients with microalbuminuria. EH patients showed increased expression of platelet CD40. In the cell coculture model, activated platelets were able to significantly induce MCP-1 release from HUVEC in a CD40L-dependent manner. EH patients showed elevated sCD40L levels with a positive correlation with MCP-1 levels. CONCLUSIONS: Platelets can contribute to enhanced MCP-1 levels in EH. MCP-1 is markedly elevated in serum of EH patients with highest levels in patients with microalbuminuria, one early sign of renal target organ damage. Further studies are required to test whether MCP-1 blocking or antiplatelet strategies may represent new therapeutic options in preventing hypertensive target organ damage.

Anti-inflammatory effects of danshen on human vascular endothelial cells in culture.

Inflammation plays a crucial role in the pathophysiology of atherosclerosis. Besides cytokines, chemokines and cell adhesion molecules, CD40 and P-selectin play important roles as key regulators of the inflammatory process in atherosclerosis. Danshen (DS) is commonly used in traditional Chinese medicine for therapy of cardiovascular diseases such as coronary artery disease. The aim of the present study was to evaluate the protective effects of DS with respect to possible anti-inflammatory effects. Human umbilical vein endothelial cells as well as platelets were incubated with an extract of DS or one of its major ingredients salvianolic acid B (Sal B), tanshinone IIA (Tansh) and protocatechuic acid (Protoc) under tumor necrosis factor (TNF)-α or ADP stimulation. Expression of CD40 and cellular adhesion molecules (VCAM-1/ICAM-1) were assessed via flow cytometry. Levels of interleukin (IL)-6, IL-8, monocyte-chemoattractant-protein (MCP)-1 as well as soluble VCAM1 and ICAM-1 in the supernatants were examined via luminex based analysis. Treatment with DS attenuated TNF-α induced expression of CD40. Furthermore, the expression of VCAM-1 and ICAM-1 as well as the release of soluble VCAM-1 and ICAM-1 were downregulated. In the cell supernatants we also observed a significant reduction of IL-6, IL8 and MCP-1. DS and its major ingredients, Sal B and Protoc, significantly inhibited TNF-induced expression and release of adhesion molecules, cytokines and chemokines as well as ADP-induced expression of platelet P-selectin. Because of the key roles of inflammatory mediators in the etiology of atherosclerosis, this work provides useful insight in understanding the pharmacological efficacy of Chinese herbal medicine.

Shear stress preconditioning modulates endothelial susceptibility to circulating TNF-alpha and monocytic cell recruitment in a simplified model of arterial bifurcations.

OBJECTIVE: Atherosclerotic plaque formation results from a combination of local shear stress patterns and inflammatory processes. This study investigated the endothelial response to shear stress in combination with the inflammatory cytokine TNF-alpha in a simplified model of arterial bifurcation. METHODS: Human umbilical vein endothelial cells (ECs) were exposed to laminar or non-uniform shear stress in bifurcating flow-through slides, followed by stimulation with TNF-alpha. To study cell adhesion, ECs were perfused with medium containing THP-1 monocytic cells. Endothelial protein expression was determined by immunofluorescence. RESULTS: Adhesion of monocytic cells to unstimulated ECs was nearly undetectable under laminar shear stress and was slightly increased under non-uniform shear stress. Exposure of ECs to non-uniform shear stress in combination with TNF-alpha induced a 12-fold increase in monocytic cell recruitment and a significant induction of endothelial E-selectin and VCAM-1 expression. Both these effects were prevented in ECs exposed to laminar shear stress. The significant differences in TNF-alpha-induced monocytic cell recruitment and adhesion molecule expression between laminar and non-uniform shear stress regions were abolished in the absence of shear stress preconditioning. Simvastatin (1 micromol/L) suppressed the non-uniform shear stress- and TNF-alpha-induced increase in monocytic cell adhesion by about 30% via inhibition of VCAM-1 expression. Resveratrol, the active component of red wine, inhibited the expression of both VCAM-1 and E-selectin, and reduced monocytic cell recruitment by 50% at 20 micromol/L. CONCLUSIONS: Non-uniform shear stress induces endothelial susceptibility to circulating TNF-alpha and adhesion of monocytic cells. Interference with this process may inhibit inflammatory response in atherosclerosis-prone regions.

FcgammaRIIa genotype is associated with acute coronary syndromes as first manifestation of coronary artery disease.

OBJECTIVE: Identification of clinically relevant determinants for acute coronary syndromes (ACS) promises reduction of ACS-associated mortality. C-reactive protein (CRP) has proved to be useful identifying people at risk for cardiovascular events. However, it is unknown whether genetic variants at Fcgamma receptor IIa (FcgammaRIIa), the main receptor for CRP, are involved in CRP-related cardiovascular risk. We evaluated the potential impact of FcgammaRIIa through a genetic association study in patients with ACS. METHODS AND RESULTS: We conducted a genetic association study among 701 consecutive patients with first event of ACS compared to 467 patients with stable angina pectoris. All patients were genotyped for a frequent functional variant at position 131 of the mature FcgammaRIIa, where the arginine (R) allele results in an increased signal transduction upon CRP binding. In our study, the R/R131 genotype was significantly associated with ACS as the first manifestation of coronary artery disease (P=1.2x10(-9), odds ratio 2.86, 95% CI: 2.06-3.99) compared to the non-R/R131 genotype. CONCLUSIONS: Our data show a genetic association of the FcgammaRIIa R/R131 genotype with a more frequent occurrence of ACS as the first manifestation of coronary artery disease, probably mediated via its interaction with CRP. Genotyping of this FcgammaRIIa variant could help to improve risk stratification in the course of coronary disease in the future.

Atorvastatin enhances interleukin-10 levels and improves cardiac function in rats after acute myocardial infarction.

LV (left ventricular) remodelling is the basic mechanism of HF (heart failure) following MI (myocardial infarction). Although there is evidence that pro-inflammatory cytokines [including TNF-alpha (tumour necrosis factor-alpha) and IL-6 (interleukin-6)] are involved in the remodelling process, only little is known about the role of anti-inflammatory cytokines, such as IL-10. As accumulating evidence has revealed that statins possess anti-inflammatory properties, the aim of the present study was to elucidate the effect of atorvastatin on the modulation of the anti-inflammatory cytokine IL-10 and its effect on LV function in rats with HF subsequent to MI. Rats with MI, induced by permanent LAD (left anterior descending) branch coronary artery ligation, were treated for 4 weeks with atorvastatin (10 mg x kg(-1) of body weight x day(-1) via oral gavage) starting on the first day after induction of MI. Cardiac function was assessed by echocardiography and cardiac catheterization 4 weeks after MI induction. Membrane-bound and soluble fractions of TNF-alpha, IL-6 and IL-10 protein, the TNF-alpha/IL-10 ratio, serum levels of MCP-1 (monocyte chemoattractant protein-1) as well as myocardial macrophage infiltration were analysed. Treatment with atorvastatin significantly improved post-MI LV function (fractional shortening, +120%; dP/dt(max), +147%; and LV end-diastolic pressure, -27%). Furthermore atorvastatin treatment markedly decreased the levels of TNF-alpha, IL-6 and MCP-1, reduced myocardial infiltration of macrophages and significantly increased myocardial and serum levels of the anti-inflammatory cytokine IL-10. Thus the balance between pro-inflammatory and anti-inflammatory cytokines was shifted in the anti-inflammatory direction, as shown by a significantly decreased TNF-alpha/IL-10 ratio. Atorvastatin ameliorated early LV remodelling and improved LV function in rats with HF subsequent to MI. Our study suggests that the modulation of the balance between pro- and anti-inflammatory cytokines towards the anti-inflammatory cytokine IL-10 is one salutary mechanism underlying how atorvastatin influences post-MI remodelling and thus improves LV function.

Interleukin-10 improves left ventricular function in rats with heart failure subsequent to myocardial infarction.

Evidence has shown that pro-inflammatory cytokines, especially TNF-alpha, are involved in the inflammatory response in the remodelling process after myocardial infarction (MI). Although IL-10, an anti-inflammatory cytokine, has been shown to antagonize some of the deleterious effects of TNF-alpha, little is known about its role in post-MI left ventricular (LV) dysfunction. The aim of the present study was to investigate whether a therapy with rhIL-10 could be beneficial in an animal model of post-MI heart failure (HF). Rats with experimental MI were treated with rhIL-10 (75 microg/kg/d sc) starting directly after MI induction, and continuing for 4 weeks. Controls were untreated MI and sham-operated rats. Cardiac function was assessed by echocardiography and cardiac catheterization 4 weeks after MI induction. Membrane-bound and soluble fractions of TNF-alpha, IL-6 and IL-10, the ratio of TNF-alpha to IL-10, serum levels of MCP-1 as well as myocardial macrophage infiltration, were analyzed. Treatment with rhIL-10 significantly improved post-MI LV function (FS +127%;, dP/dt(max) +131%; LVEDP -36%). This effect was associated with a significant decrease in pro-inflammatory cytokine and chemokine levels (TNF-alpha, IL-6, MCP-1) and furthermore resulted in a reduced myocardial infiltration of macrophages.

Pharmacological inhibition of RhoA signaling prevents connective tissue growth factor induction in endothelial cells exposed to non-uniform shear stress.

Shear stress changes play an important role in atheroma formation. This study focussed on atherogenic protein expression under non-uniform shear stress and the pharmacological modulation of shear-related endothelial dysfunction. Bifurcating flow-through cell culture slides were used to expose HUVECs to steady laminar or non-uniform shear stress for 18 h at 10 dyn/cm(2). Protein expression was determined by immunofluorescence, and quantified using MetaVue software. Laminar shear stress resulted in cell alignment, reduced F-actin fibers, and significant induction of endothelial nitric oxide synthase expression. Under non-uniform shear stress at bifurcations, minor upregulation of adhesion molecules was observed. Connective tissue growth factor (CTGF) was significantly downregulated by laminar shear stress and induced in cells exposed to non-uniform shear stress. CTGF upregulation by non-uniform shear stress was RhoA-dependent, because it was almost completely inhibited in cells transfected with dominant negative RhoA-N19, and when cells were treated with 1 micromol/L simvastatin during flow. Pre-incubation of HUVECs with inhibitors of Rho-associated kinase before exposure to flow significantly suppressed the CTGF induction in regions of non-uniform shear stress. In conclusion, non-uniform shear stress-dependent CTGF expression requires active RhoA and can be prevented pharmacologically. Interference with shear stress-induced protein expression may inhibit endothelial dysfunction in atheroprone vessel regions.

Detection of coronary artery stenoses using multi-detector CT with 16 x 0.75 collimation and 375 ms rotation.

AIMS: Insufficient spatial and temporal resolutions have limited image quality and accuracy of multi-detector CT (MDCT) for coronary artery visualization and detection of stenoses. We assessed the accuracy of a new 16-slice scanner with 370 ms rotation and 0.75 mm collimation for detection of coronary stenoses using an analysis approach based on coronary artery segments. METHODS AND RESULTS: Fifty consecutive patients scheduled for diagnostic coronary angiography in stable clinical condition and sinus rhythm were enrolled. All patients with a heart rate > 60 b.p.m. received 100 mg atenolol p.o. and up to four doses of 5 mg metoprolol i.v. before the scan. MDCT was performed using 16 x 0.75 mm collimation, 120 kV, and ECG-gated tube current modulation. Ninety millilitres of contrast agent was injected intravenously. MDCT images were visually analysed using the 16-segment coronary artery model of the American Heart Association and compared with invasive, quantitative coronary angiography in a blinded fashion. A significant stenosis was assumed if the diameter reduction was > or = 50%. Mean heart rate was 58 b.p.m. during MDCT. After exclusion of two patients with not fully evaluable data sets, MDCT correctly identified at least one coronary stenosis in all 25 patients with significant coronary lesions in angiography and correctly demonstrated the absence of stenoses in 19/23 patients (sensitivity 100%, specificity 83%). Sensitivity and specificity for all 50 patients were 93 and 83%, respectively. On a per-segment basis, nine coronary segments distal of total occlusions and 128 coronary segments with a reference diameter < 1.5 mm were excluded from the analysis. Twenty-eight of the included 663 segments (4%) were unevaluable due to calcification or motion artefact. In the remaining 635 segments, 50/53 stenoses were detected by MDCT (sensitivity 94%, specificity 96%, negative predictive value 99%, positive predictive value 69%). CONCLUSION: Increasing temporal and spatial resolutions of MDCT lead to improved evaluation and diagnostic accuracy for detection of coronary stenoses.

Enhanced levels of platelet P-selectin and circulating cytokines in young patients with mild arterial hypertension.

BACKGROUND: Emerging evidence links inflammation to atherosclerosis (AS). Although some studies have addressed the role of inflammation in patients with arterial hypertension (AH), its overall contribution in AH is far from being understood. Therefore, the present pilot study was designed to examine the role of platelet P-selectin and various inflammatory mediators in young patients with moderate AH without signs of target organ damage. METHODS AND RESULTS: Fifteen patients with mild AH [33.8 +/- 7.3 years, mean arterial pressure (MAP) 106.6 +/- 10.4 mmHg] and 15 healthy normotensive controls (31.7 +/- 10.6 years) were examined. Platelet P-selectin was analysed by flow cytometry. Plasma levels of monocyte-chemoattractant-protein-1 (MCP-1), high-sensitivity C-reactive protein (hsCRP), interleukin (IL)-6, tumour necrosis factor alpha (TNFalpha), and IL-10 levels were measured by enzyme immunoassay (EIA). Patients with mild AH showed significantly enhanced expression of platelet P-selectin [17.2 +/- 5.4 versus 10.6 +/- 4.2 mean fluorescence intensity (MFI), P < 0.001]. P-selectin expression positively correlated with MAP (r = 0.43, P < 0.05). Furthermore, patients with mild AH had significantly enhanced plasma levels of hsCRP (2.7 +/- 3.8 versus 0.6 +/- 0.9 mg/l, P < 0.01), IL-6 (1.4 +/- 0.7 versus 0.6 +/- 0.3 pg/ml, P < 0.001), TNFalpha (2.8 +/- 0.7 versus 2.4 +/- 0.4 pg/ml, P < 0.05), and MCP-1 (291.3 +/- 100.7 versus 214.3 +/- 8.3 pg/ml, P < 0.05). IL-6 levels positively correlated with hsCRP levels (r = 0.47, P < 0.05) and mean arterial pressure (MAP) (r = 0.44, P < 0.05). CONCLUSIONS: This pilot study demonstrates that in an early stage of AH, inflammatory pathways are already activated. Besides pro-inflammatory cytokines, platelets seem to play a significant role in mediating inflammation in AH, which could lead to target organ injury. Further investigations have to clarify the role of early anti-inflammatory therapy, in patients with mild to moderate AH, in alleviating hypertensive target organ damage.

Emergence of dendritic cells in rupture-prone regions of vulnerable carotid plaques.

Dendritic cells (DC), which are critically involved in various immunological disorders, were detected in atherosclerotic plaques in 1995. Since DC might be related to the immunological processes in atherosclerosis (AS), we analyzed the emergence of DC and other inflammatory cells in different stages of AS. Serial cross-sections of 44 carotid specimens were immunohistochemically analyzed for the presence of DC, T cells, macrophages, and HLA-DR. Atherosclerotic specimens were histologically defined as initial lesions, advanced stable, or vulnerable plaques. In initial lesions significantly lower DC numbers were detected than in advanced plaques (P < 0.001). For advanced plaques, DC numbers were significantly higher in vulnerable than in stable plaques (P = 0.005). In contrast to initial lesions, approximately 70% of DC in advanced plaques exhibited a mature phenotype (CD83+, DC-LAMP+), indicating a functional activity of DC. In plaques of patients with acute ischemic symptoms DC numbers were markedly elevated (P = 0.03), whereas significantly lower DC numbers and more often a stable plaque morphology were detected in statin-treated patients (P = 0.02). DC clusters with a strong HLA-DR expression and frequent DC-T cell contacts were located particularly in the rupture-prone plaque regions and at complications. The results of the present study indicate that DC might contribute to plaque destabilization through an activation of T cells.

HMG-CoA reductase inhibitors suppress maturation of human dendritic cells: new implications for atherosclerosis.

The beneficial effects of statins in atherosclerosis have been partly attributed to their immunomodulating functions. Dendritic cells (DC), which are "professional" antigen-presenting cells, were recently detected in atherosclerotic plaques. It is assumed that DC play a critical role in the immunological processes related to atherosclerosis. Thus, we investigated the effects of statins on maturation and antigen-presenting function of DC. Human monocyte-derived DC were incubated with simvastatin or atorvastatin (1-10microM) for different periods (1-48h), and were subsequently stimulated with a cytokine cocktail (1.25ng/ml TNF-alpha, 1ng/ml Il-1beta, and 0.5microg/ml prostaglandin E(2)) to induce maturation. In contrast to untreated DC, statin-preincubated DC exhibited an immature phenotype and a significantly lower expression of the maturation-associated markers CD83, CD40, CD86, HLA-DR, and CCR7. The inhibitory statin effect was completely reversed by mevalonate or geranylgeranyl pyrophosphate. In addition, preincubation with statins significantly reduced the ability of cytokine-stimulated DC to induce T cell proliferation. In the present study, we have shown that statins inhibit the maturation and antigen-presenting function of human myeloid dendritic cells, thus maybe contributing to their beneficial effects in atherosclerosis. Therefore, the use of statins as immunomodulators might also provide a new therapeutic approach to other immunological disorders.

Enhanced levels of CD154 (CD40 ligand) on platelets in patients with chronic heart failure.

BACKGROUND: Inflammation plays a significant contributory role in the pathogenesis of chronic heart failure (CHF). Previous data have shown enhanced plasma levels of proinflammatory cytokines, i.e. TNF-alpha and IL-6, as well as a persistent immune activation in patients with CHF. Furthermore, the immune modulator CD154 has been receiving increased attention, since it plays a key role in the pathophysiology of multicellular vascular events such as thrombosis, inflammation and atherosclerosis. Since CD154 initiates and maintains the release of proinflammatory cytokines from endothelial cells, its potential role for the development and progression of CHF is of interest. METHODS: Fifty patients with CHF (aged 66.9+/-12.6 years, mean ejection fraction 22.1+/-9.2%, NYHA II-IV, 39 of ischemic origin, 11 with idiopathic dilated cardiomyopathy) and 15 healthy controls (aged 62.5+/-9.8 years) were examined. Thirty-two patients were taking aspirin (100 mg/day). Blood was drawn from a peripheral vein and immediately fixed with 1% paraformaldehyde, incubated with anti-CD154, anti-P-selectin, and anti-CD61 and thereafter analyzed by flow cytometry. RESULTS: Patients with CHF showed significantly enhanced expression of platelet-bound CD154 and P-selectin as compared to controls (CD154: median 35.6 25th percentile: 26.3; 75th percentile: 44.6 vs. 12.8; 25th: 6.8; 75th: 15.6 mean fluorescence intensity [MFI], P<0.001; P-selectin: median 3.2 25th percentile: 1.9; 75th percentile: 5.9 vs. 1.4; 25th: 1.2; 75th: 1.9, MFI, P<0.001). CD154 expression on platelets positively correlated with increasing NYHA-class. In contrast, no significant differences in serum levels of soluble CD154 or CD40 expression on monocytes were detected in the study groups. Antiplatelet-therapy with aspirin did not influence CD154 or P-selectin expression on platelets. CONCLUSION: Our pilot study demonstrates significantly enhanced levels of CD154 on platelets in patients with CHF. This suggests that the CD40-CD154 axis may contribute to the proinflammatory milieu, which exists in CHF and thus may play a pathogenic role in the development and progression of CHF.