Acute myocardial infarction and increased soluble intercellular adhesion molecule-1: a marker of vascular inflammation and a risk of early restenosis?

Intercellular adhesion molecule 1 rs5498 polymorphism is associated with the risk of myocardial infarction

Several studies addressed the association between Intercellular adhesion molecule 1 (ICAM-1) rs5498 polymorphism and Myocardial Infarction (MI) risk. However, they addressed conflicting findings. Therefore, the aim of this study was to explore whether ICAM-1 gene rs5498 polymorphism plays an important role in modifying the risk of MI. A meta-analysis was conducted on the association between ICAM-1 rs5498 polymorphism and MI. 12 eligible studies involving 1,696 cases and 3,039 controls were included in the meta-analysis. Meta-analysis revealed that ICAM-1 rs5498 polymorphism showed a strongly positive correlation with MI and could be viewed as a protective factor for MI. Furthermore, subgroup analysis according to ethnicity indicated that ICAM-1 rs5498 polymorphism decreased the risk of MI among Caucasian and Asian populations. In conclusion, ICAM-1 rs5498 polymorphism was associated with the decreased risk of MI. Larger sample size studies with more diverse ethnic populations are needed to confirm these findings.

Changes in CCR2 chemokine receptor expression and plasma MCP-1 concentration after the implantation of bare metal stents versus sirolimus-eluting stents in patients with stable angina

BACKGROUND

Although restenosis after successful coronary stenting is associated with changes in adhesion molecules and chemokines, it is unclear whether the differential effects of these molecules between a bare metal stent (BMS) and sirolimus-eluting stent (SES) may help to prevent coronary restenosis. The aim of this clinical study was to compare the expression levels of those molecules after elective placement of either a BMS or SES.

METHODS AND RESULTS

The subjects included 32 consecutive patients with stable angina who had undergone successful coronary stenting and who randomly received either a BMS (n=16) or SES (n=16). Quantitative angiographic analysis 6 months after stenting showed that the minimal lumen diameter was significantly greater in the SES as compared to the BMS group, while the percent diameter stenosis and in-stent lumen loss were significantly lower. Plasma monocyte chemotactic protein-1 (MCP-1) increased significantly after 14 days and 6 months and monocyte CCR2 expression increased 24 hr and 48 hr after stenting in the BMS but not the SES group. Changes in plasma MCP-1 (DeltaMCP-1) within 6 months after stenting correlated significantly with in-stent lumen loss. The DeltaMCP-1 (between 6 months and baseline) was significantly related only to the lumen loss (r=0.443, p=0.023), which suggests that the reduction of MCP-1 is the best contributor to decreased lumen loss.

CONCLUSIONS

These data suggest that reduction in MCP-1 production by SES may be one mechanism to prevent restenosis after coronary stenting.

Enhanced inflammatory response to coronary stenting marks the development of clinically relevant restenosis

OBJECTIVES

The aims of this study were to investigate the effect of coronary stenting on the release of cytokines and cell-mediated immunity factors and to evaluate the association between inflammation and clinical outcomes at 6 months.

BACKGROUND

Circulating levels of inflammatory markers and cytokines are elevated in patients with acute coronary syndromes and are related to an unfavorable outcome. The aims of this study were to investigate the effect of coronary stenting on the release of cytokines and cell-mediated immunity factors and to evaluate the association between inflammation and clinical outcomes at 6 months.

METHODS

Forty patients with single native coronary artery disease treated with stenting were enrolled. Peripheral venous blood samples were collected before and 6 h, 48 h, and 12 weeks after stenting. Serum concentrations of high-sensitivity C-reactive protein, interleukin-6, interleukin-8, tumor necrosis factor-alpha (markers of inflammation) and serum-soluble interleukin-2 receptor for T-lymphocyte activation (sIL2-R, marker of cell-mediated immunity) were measured. Patients also were evaluated clinically one, 3, and 6 months post-stenting or when they presented with cardiovascular symptoms to identify major adverse cardiac events (cardiac death, MI, revascularization).

RESULTS

Concentrations of interleukins 6 and 8 and tumor necrosis factor-alpha peaked at 6 h (11.0, 12.6, and 5.3 pg/ml, respectively). The peak level of high-sensitivity C-reactive protein (2.77 mg/dL) occurred 48 h post stenting, while sIL2-R peaked (495 U/ml) at 12 weeks. Patients who experienced restenosis had higher levels of C-reactive protein at 48 h (4.94 vs. 1.84 mg/dl; P = 0.043) and of IL-8 at 6 h (26.75 vs. 13.55 pg/mL; P = 0.048) than those without restenosis.

CONCLUSIONS

Proinflammatory cytokines and inflammatory markers are released into the peripheral circulation early after coronary stenting, and increased levels of some are associated with clinically relevant restenosis.

Restenosis after percutaneous angioplasty: the role of vascular inflammation

Restenosis after endovascular treatment of atherosclerotic lesions in the peripheral, cerebrovascular, and coronary circulation is the major drawback of this minimally invasive technique. Although certain advances have been made during recent years to improve patency rates after percutaneous angioplasty, restenosis remains a challenging clinical problem. Understanding factors that contribute to the pathophysiology of late lumen loss is an effective strategy to improving patients' postangioplasty outcome. Vascular inflammation after balloon angioplasty or stent implantation has been identified as a cornerstone of the restenotic process, and several markers of inflammation have been referred to as potential predictors of outcome. This article reviews recent findings on the issue of inflammation and restenosis after percutaneous angioplasty with special attention given to the role of inflammatory parameters as markers for the restenosis risk in the peripheral vessel area.

Lipoic acid in multiple sclerosis: a pilot study

Lipoic acid (LA) is an antioxidant that suppresses and treats an animal model of multiple sclerosis (MS), experimental autoimmune encephalomyelitis. The purpose of this study was to determine the pharmacokinetics (PK), tolerability and effects on matrix metalloproteinase-9 (MMP-9) and soluble intercellular adhesion molecule-1 (sICAMP-1) of oral LA in patients with MS. Thirty-seven MS subjects were randomly assigned to one of four groups: placebo, LA 600 mg twice a day, LA 1200 mg once a day and LA 1200 mg twice a day. Subjects took study capsules for 14 days. We found that subjects taking 1200 mg LA had substantially higher peak serum LA levels than those taking 600 mg and that peak levels varied considerably among subjects. We also found a significant negative correlation between peak serum LA levels and mean changes in serum MMP-9 levels (T = -0.263, P =0.04). There was a significant dose response relationship between LA and mean change in serum sICAM-1 levels (P =0.03). We conclude that oral LA is generally well tolerated and appears capable of reducing serum MMP-9 and sICAM-1 levels. LA may prove useful in treating MS by inhibiting MMP-9 activity and interfering with T-cell migration into the CNS.

Inflammation as a mechanism and therapeutic target for in-stent restenosis

Restenosis following coronary stenting has long been attributed to neointimal proliferation, thrombosis, and negative remodeling. More recently, the important role of inflammation in vascular healing has also been increasingly well understood. From animal models and from clinical experience, we know that endothelial injury, platelet and leukocyte interactions, and subcellular chemoattractant and inflammatory mediators are pivotal in the development of the inflammatory response following stent implantation. By examining the specific mechanisms governing the inflammatory response to percutaneous coronary intervention, we may gain insight into potential therapeutic targets and strategies to prevent restenosis in clinical practice.

Increase in soluble E-selectin level after PTCA and stent implantation: a potential marker of restenosis

BACKGROUND

E-Selectin is expressed only on activated endothelial cells, and may be used as a marker of endothelial activation. The relationship between soluble form of E-selectin (sE-selectin) and development of restenosis after balloon angioplasty (PTCA) is controversial, and there are no data for after stent implantation. We evaluated the role of serially measured sE-selectin levels in predicting the development of restenosis after PTCA and stent implantation.

METHODS

In sixty-one patients with stable angina pectoris who underwent PTCA (n=20) or stent implantation (n=41), peripheral blood samples were taken just before (baseline), at 3 and at 24 h after the intervention. sE-Selectin levels were measured by ELISA. Coronary angiography was repeated at 4-6 months after the intervention, and > or =50% stenosis at the site of the intervention was regarded as restenosis. Levels and time course of sE-selectin after the intervention were compared in patients with and those without restenosis.

RESULTS

sE-Selectin levels of the patients with and those without restenosis were similar at each of the three measurements, and significantly increased after the intervention both in the PTCA and stent groups (P<0.001 for both groups). Posthoc analysis showed that sE-selectin levels increased significantly at 3 h after PTCA (P=0.024) and stent implantation (P=0.018), and did not change thereafter in patients with restenosis. In the nonrestenotic group, sE-selectin did not change significantly in the 24 h following PTCA, however, a significant difference was observed only by comparing the values at baseline with those at 24 h after stent implantation (P=0.021).

CONCLUSIONS

A substantial increase in sE-selectin levels early (at 3 h) after PTCA and stent implantation may predict development of restenosis.

Increased Expression of Monocyte CD11a and Intracellular Adhesion Molecule-1 in Patients With Initial Atherosclerotic Coronary Stenosis

BACKGROUND

Cell adhesion molecules have been implicated in the adhesion of leukocytes to endothelial cells and therefore play a role in atherosclerosis, which is a frequent cause of morbidity and mortality in patients with coronary artery disease (CAD) or undergoing hemodialysis (HD). The levels of expression of leukocyte adhesion molecules were evaluated in patients with CAD or HD.

METHODS AND RESULTS

The expression of leukocyte (ie, neutrophil, monocyte and lymphocyte) surface CD11a, CD18, intracellular adhesion molecule-1 (ICAM-1), very late antigen-4 alpha (VLA-4 alpha) and L-selectin was investigated by flow cytometry in 20 patients who were initially diagnosed with CAD (CAD group), 15 patients with coronary re-stenosed vessels (RESTE group), 20 undergoing HD (HD group) and 20 without CAD (CONT group). Monocyte surface expression of both CD11a and ICAM-1 in the CAD group was significantly higher than in the CONT group. Interestingly, when 15 patients with RESTE were analyzed, they showed monocyte CD11a and ICAM-1 expression levels comparable to those in the CONT group. On the other hand, there were no significant differences in the expression of CD11a, CD18, L-selectin or VLA-4 alpha between the HD group and CONT group, but monocyte L-selectin was increased in the CAD group compared with the CONT group.

CONCLUSIONS

Because CD11a and CD18 are expressed on the cell surface as a heterodimer and ICAM-1 is a ligand for CD11a/CD18, this increased expression of CD11a and ICAM-1 may affect the development of initial atherosclerotic coronary stenosis, but not re-stenosis.

Downregulation of PPARγ expression in peripheral blood monocytes correlated with adhesion molecules in acute coronary syndrome

BACKGROUND

Peroxisome proliferator-activated receptor-gamma (PPARgamma) is a nuclear hormone receptor and may regulate the metabolism of lipids, inhibit monocytes/macrophages function and reduce the production of cell adhesion molecules and some inflammatory factors. Thus, it may affect the occurrence and progression of atherosclerosis.

METHODS

Forty-three patients with acute coronary syndrome and 34 control subjects were studied for PPARgamma expression in peripheral blood monocytes by reverse transcription-polymerase chain reaction (RT-PCR), and adhesion molecules were measured by enzyme-linked immunosorbent assay (ELISA).

RESULTS

Expression of PPARgamma in peripheral blood monocytes was significantly reduced in acute coronary syndrome, which was inversely associated with intercellular adhesion molecule 1 (r=-0.339, P<0.05), vascular cell adhesion molecule 1 (r=-0.331, P<0.05) and body mass index (r=-0.334, P<0.05), respectively, and positively correlated with apoA1 (r=0.289, P<0.05).

CONCLUSIONS

The reduced expression of PPARgamma in peripheral blood monocytes of patients with acute coronary syndrome is inversely associated with plasma soluble adhesion molecules, suggesting that PPARgamma may be involved in acute coronary syndrome.

Restenosis after femoropopliteal PTA and elective stent implantation: predictive value of monocyte counts

PURPOSE

To investigate the association of baseline peripheral blood monocyte counts and restenosis after femoropopliteal percutaneous transluminal angioplasty (PTA) and PTA plus elective stent implantation.

METHODS

Three hundred thirty consecutive patients (170 men; median age 71 years, interquartile range 61-78) with peripheral artery disease underwent femoropopliteal PTA (n=258) or PTA plus elective stent implantation (n=72). Multivariate Cox regression analysis was used to determine the predictive value of baseline peripheral blood monocyte counts on the rate of restenosis (> or =50% luminal reduction) in follow-up.

RESULTS

Cumulative patency at 6 and 12 months was 55% and 39% after PTA and 70% and 41% after elective stenting, respectively (p=0.19). Pretreatment monocyte counts (in tertiles) were associated with restenosis after PTA (p=0.002) and stent implantation (p=0.02). Compared to patients with monocyte counts <0.3x10(9)/L (lower tertile, n=128), patients with monocytes from 0.3 to 0.4x10(9)/L (middle tertile, n=91) had a 1.8-fold increased adjusted risk for restenosis (95% CI 1.1 to 2.8, p=0.01). Patients with monocytes >0.4x10(9)/L (upper tertile, n=87) had a 2.3-fold increased adjusted risk (95% CI 1.4 to 3.5, p<0.0001).

CONCLUSIONS

Baseline monocyte counts were associated with restenosis after femoropopliteal PTA and elective stent implantation, suggesting that circulating monocytes play a pivotal role in the development of recurrent lumen narrowing.

Pre-procedural expression of Mac-1 and LFA-1 on leukocytes for prediction of late restenosis and their possible correlation with advanced coronary artery disease

BACKGROUND

The activation status of the inflammatory system has been suggested to play an important role in predicting restenosis. Activation of leukocyte adhesion molecules occur after coronary intervention and the level of activation correlates to restenosis. However, little is known about the specific role of adhesion molecules before intervention. The purpose of this study concerned the search for differences in the expression level of selected adhesion molecules to identify suitable tools for the pre-procedural identification of restenosis patients prior to angioplasty.

METHODS

Blood samples of 31 patients undergoing elective coronary angiography were obtained just before intervention. Seven healthy volunteers were also enrolled. Surface expression of leukocyte adhesion molecules Mac-1 (CD11b/CD18), LFA-1 (CD11a/CD18), L-Selectin (CD62L), ICAM-1 (CD54), and MHC-II (HLA-DR) were assessed by flow cytometry. Patients with a successful angioplasty received a follow-up angiography after six months.

RESULTS

According to the clinical and angiographic data, patients were divided into four groups: control (N = 14), no restenosis (N = 11), restenosis (N = 4), and advanced coronary artery disease (CAD, N = 9). The restenosis group and the advanced CAD group showed higher expression of Mac-1 and LFA-1 on monocytes and neutrophils compared to the other groups. Using the pre-procedural expression levels, patients with restenosis could be predicted by discriminant analysis with CD11a, CD11b, and CD18 (average recognition index = 95.5%).

CONCLUSIONS

The data of this pilot study indicate that pre-procedural activation status of CD11a and CD11b may play a role in the subsequent development of restenosis. Moreover, CD11a, CD11b, and CD18 may be helpful as indicators for the progression of CAD.

C/T polymorphism of the intercellular adhesion molecule-1 gene (exon 6, codon 469). A risk factor for coronary heart disease and myocardial infarction

BACKGROUND

The intercellular adhesion molecule-1 (ICAM-1) mediates the interaction of activated endothelial cells with leukocytes and plays a fundamental role in the pathogenesis of coronary atherosclerosis. ICAM-1 single-base C/T polymorphism, which determines an amino acid substitution in the ICAM-1 protein in exon 6 codon 469, has been described. Our purpose was to determine whether this C/T polymorphism influences the risk of coronary heart disease (CHD) and myocardial infarction (MI) in humans.

METHODS AND RESULTS

We enrolled 349 patients with angiographically documented CHD, including a sub-group of 179 patients with acute or chronic MI. The control group consisted of 213 patients with normal left ventricular function and no documented evidence of CHD. All patients and controls were Germans genotyped by polymerase chain reaction and allele-specific oligonucleotide techniques for the ICAM-1 polymorphism. In the patients with CHD and MI the frequencies of the T genotype (TT+TC) were significantly higher than the CC genotype compared to the control subjects (P<0.001). With the additional use of multivariable logistic regression analysis for CHD (TT+TC versus CC; P=0.011, odds ratio 2.21, 95% CI 1.20-4.07), we found a significant association between CHD and MI and the TT and TC genotype of the ICAM-1 gene polymorphism.

CONCLUSIONS

These results suggest that the TT and TC genotype of the ICAM-1 gene polymorphism in codon 469 is a genetic factor that may determine an individual's susceptibility for CHD and MI.

Tumor necrosis factor-alpha in cardiovascular biology and the potential role for anti-tumor necrosis factor-alpha therapy in heart disease

The functional role of tumor necrosis factor (TNF)-alpha in the heart has been extensively studied over the last 15 years. Collectively, these studies have demonstrated that TNF-alpha has both diverse and potentially conflicting roles in cardiac function and pathology. These include beneficial effects, such as cardioprotection against ischemia, myocarditis, and pressure overload, as well as potentially adverse effects, such as the development of atherosclerosis, reperfusion injury, hypertrophy, and heart failure. TNF-alpha antagonist therapy recently has been demonstrated to be clinically applicable in inflammatory conditions, and clinical trials are currently in progress in the use of these agents in cardiovascular diseases. The scope for clinical applications of anti-TNF-alpha therapy in cardiovascular diseases is potentially extensive. Hence, this review has been undertaken to evaluate the cardiovascular effects of this pleiotropic cytokine and to evaluate the potential of targeting this cytokine in cardiovascular therapeutics. An overview of the TNF-alpha peptide and its associated signaling are described. This is followed by a discussion of the known roles of TNF-alpha in cardiac physiology and in a diverse array of cardiac pathologies. Reference to experimental and clinical studies using anti-TNF-alpha therapies are described where applicable. The postulated role of TNF-alpha signaling concerning innate cardiac cellular processes that may have direct adaptive effects in the heart will be reviewed with respect to future research directions. Finally, the author postulates that attenuation of TNF-alpha biosynthesis in selected individuals will need to be tested if true benefits of this therapeutic approach are to be realized in the management of cardiovascular diseases.

Reperfusion injury after focal myocardial ischaemia: polymorphonuclear leukocyte activation and its clinical implications

The only way to rescue ischaemic tissue is to re-instate the oxygen supply to the tissue. However reperfusion of the ischaemic area not only oxygenates the tissue but also initiates a cascade of processes, which may in some cases result in temporary dysfunction of the myocardium. In order to devise protective measures, it is essential to understand the mechanisms and the triggers of this reperfusion phenomenon. In this review we will mainly focus on the inflammatory response caused by reperfusion. We will cover the different steps of polymorphonuclear leukocyte activation and will briefly discuss the molecular biology of the receptors involved. The currently used pharmacological medications in acute cardiology will be reviewed and in particular their actions on polymorphonuclear leukocyte activation, adhesion and degranulation. This review is a compilation of the current knowledge in the field and the therapeutic progress in the prevention of reperfusion injury made today.

Mouse model of femoral artery denudation injury associated with the rapid accumulation of adhesion molecules on the luminal surface and recruitment of neutrophils

Techniques of arterial injury commonly used in animals to mimic endovascular procedures are not suitable for small mouse arteries. This has limited examination of the response to arterial injury in genetically modified mice. We therefore sought to develop a model of transluminal injury to the mouse femoral artery that would be reproducible and result in substantial levels of intimal hyperplasia. Mice of the C57BL/6 strain underwent bilateral femoral artery denudation by passage of an angioplasty guidewire. Intimal hyperplasia was observed in 10% of injured arteries at 1 week, in 88% at 2 weeks, and in 90% at 4 weeks. The mean intimal-to-medial area ratio reached 1.1+/-0.1 at 4 weeks. No intimal proliferation was found in control sham-operated arteries. One hour after injury, the denuded surface was covered with platelets and leukocytes, predominantly neutrophils. This was associated with the accumulation of P-selectin, intercellular adhesion molecule-1, and vascular cell adhesion molecule-1. Expression of these adhesion molecules was not seen in the underlying medial smooth muscle cells. At 24 hours, few neutrophils remained on the denuded surface. At 1 week, macrophages and platelets were present in the vessel wall, partially covered by regenerated endothelium. Transluminal wire injury to the mouse femoral artery induces abundant intimal hyperplasia formation by 2 and 4 weeks and elicits the rapid accumulation of leukocytes and adhesion molecules on the denuded luminal surface. This model will be a valuable tool to study arterial injury in genetically modified mouse models.

Preanalytical Factors (Biological Variation) and the Measurement of Serum Soluble Intercellular Adhesion Molecule-1 in Humans: Influence of the Time of Day, Food Intake, and Physical and Psychological Stress

Background: Adhesion proteins such as soluble intercellular adhesion molecule-1 (sICAM-1) may be important markers for early atherosclerosis and some other diseases. To devise optimum specimen collection procedures, we investigated the effects on serum sICAM-1 of several preanalytical factors (factors that occur before a specimen is analyzed) such as the time of the day, food ingestion, and physical and psychological stress.

Methods: Three sets of experiments were conducted: (a) 30 subjects were investigated during the morning, after an overnight fast, and then after the usual breakfast and at 1200; (b) 20 subjects were studied before and after exposure to thermal stress (sauna + swimming in ice-cold water); and (c) 15 volunteers were investigated after their driving license examination and during a (stress-free) control session. Conventional methods and kits were used to determine the blood picture and serum sICAM-1.

Results: All of these preanalytical factors induced a significant increase (∼10%) in the concentration of sICAM-1.

Conclusion: It is advisable to consider timing, food intake, and stress when collecting specimens and analyzing data on the concentration of sICAM-1 in serum.