Circulating intercellular adhesion molecule-1 and E-selectin in patients with acute coronary syndrome

Kinetics and prognostic value of soluble VCAM-1 in ST-segment elevation myocardial infarction patients

BACKGROUND

Soluble vascular cell adhesion molecule-1 (sVCAM-1) is a biomarker of endothelial activation and inflammation. There is still controversy as to whether it can predict clinical outcome after ST-elevation myocardial infarction (STEMI). Our aim was to assess the sVCAM-1 kinetics and to evaluate its prognostic predictive value.

METHOD

We prospectively enrolled 251 consecutive STEMI patients who underwent coronary revascularization in our university hospital. Blood samples were collected at admission, 4, 24, 48 h and 1 month after admission. sVCAM-1 serum level was assessed using ELISA assay. All patients had cardiac magnetic resonance imaging at 1-month for infarct size (IS) and left ventricular ejection fraction (LVEF) assessment. Clinical outcomes were recorded over 12 months after STEMI.

RESULTS

sVCAM-1 levels significantly increased from admission up to 1 month and were significantly correlated with IS, LVEF, and LV end-systolic and diastolic volume. (H48 area under curve (AUC) ≥ H48 median) were associated with an increased risk of adverse clinical events during the 12-month follow-up period with a hazard ratio (HR) = 2.6 (95% confidence interval [CI] of ratio = 1.2-5.6, p = .02). The ability of H48 AUC for sVCAM-1 to discriminate between patients with or without the composite endpoint was evaluated using receiver operating characteristics with an AUC at 0.67 (0.57-0.78, p = .004). This ability was significantly superior to H48 AUC creatine kinase (p = .03).

CONCLUSIONS

In STEMI patients, high sVCAM-1 levels are associated with a poor clinical outcome. sVCAM-1 is an early postmyocardial infarction biomarker and might be an interesting target for the development of future therapeutic strategies.

Caloric restriction, physical exercise, and CB1 receptor blockade as an efficient combined strategy for bodyweight control and cardiometabolic status improvement in male rats

Obesity is critically associated with the development of insulin resistance and related cardiovascular and kidney diseases. Several strategies for weight loss have been developed but most of them exhibit a post-intervention rebound effect. Here, we aimed to design combined weight-loss strategies of caloric restriction, physical exercise, and administration of a CB1 receptor blocker to inhibit food intake that also accomplish the objectives of lost-weight maintenance and improvement of cardiovascular and renal function. Diet-induced obesity (DIO) was generated in Sprague Dawley rats for 12 weeks to test the effects of single or combined strategies (i.e. caloric restriction, mixed training protocol, and/or administration of appetite suppressant) on caloric intake, body weight, cardiovascular and renal functionality resulting from a weight-loss intervention period of 3 weeks followed by 6 weeks of weight maintenance. Consumption of a high-fat diet (HFD) caused a significant increase in body weight (5th week of the experimental period) and led to the development of insulin resistance, cardiovascular, and renal alterations. The different interventions tested, resulted in a significant body weight loss and improved glucose metabolism, aerobic capacity, electrocardiographic parameters, vascular expression of adhesion molecules and inflammatory mediators, and renal functionality, reaching values similar to the control normocaloric group or even improving them. Successful maintenance of lost weight was achieved along a 6-week maintenance period in addition to adequate health status. In conclusion, the weight-loss and maintenance intervention strategies tested were efficient at reversing the obesity-related alterations in body weight, glucose metabolism, aerobic capacity, cardiovascular and renal functionality. The beneficial action was very consistent for caloric restriction and physical exercise, whereas administration of a CB1 receptor blocker complemented the effects of the prior interventions in some parameters like body weight or aerobic capacity, and showed specific actions in renal status, increasing glomerular filtration rate and diuresis. Overall, the novelty of our study relies on the easy implementation of combined strategies for effective weight management that resulted in significant health benefits.

The impact of selectins on mortality in stable carotid atherosclerosis

Cellular adhesion molecules also known as selectins promote recruitment of inflammatory cells into the arterial wall where they interact with lipid particles leading subsequently to plaque formation. The intercellular adhesion molecule-1 (ICAM-1), the vascular cell adhesion molecule-1 (VCAM-1) and the endothelial-leukocyte adhesion molecule 1 (ELAM-1) also known as E-selectin mediate the attachment of leukocytes and have been implicated in the destabilisation of atherosclerotic plaques. Therefore, we hypothesised that plasma selectin levels are associated with adverse clinical outcome. We prospectively studied 855 patients with sonographically confirmed carotid atherosclerosis. During a median follow-up of 6.2 years, corresponding to 5,551 overall person-years, 275 patients (26 %) died. We detected a significant association between cardiovascular mortality and ICAM-1 (adjusted hazard ratio [HR]: 3.43, 95 % confidence interval [CI] 2.00-5.88, p< 0.001) as well as VCAM-1 (adjusted HR: 2.51, 95 %CI 1.45-4.34, p=0.001) when comparing the fourth with the first quartile. Comparable results were obtained for all-cause mortality. In contrast, we could not detect a significant association between E-selectin and all-cause or cardiovascular mortality. We identified the selectins ICAM-1 and VCAM-1 as strong and independent predictors of all-cause and cardiovascular mortality in patients with stable carotid atherosclerosis. These molecules are elevated in states of endothelial activation and might assist to monitor anti-atherosclerotic therapy and select those patients with carotid atherosclerosis, who are at higher risk for cardiovascular events.

Increased circulating macrophage migration inhibitory factor levels are associated with coronary artery disease

BACKGROUND

To evaluate the macrophage migration inhibitory factor and E-selectin levels in patients with acute coronary syndrome.

MATERIALS/METHODS

We examined the plasma migration inhibitory factor and E-selectin levels in 87 patients who presented with chest pain at our hospital. The patients were classified into two groups according to their cardiac status. Sixty-five patients had acute myocardial infarction, and 22 patients had non-cardiac chest pain (non-coronary disease). We designated the latter group of patients as the control group. The patients who presented with acute myocardial infarction were further divided into two subgroups: ST-elevated myocardial infarction (n = 30) and non-ST elevated myocardial infarction (n = 35).

RESULTS

We found higher plasma migration inhibitory factor levels in both acute myocardial infarction subgroups than in the control group. However, the E-selectin levels were similar between the acute myocardial infarction and control patients. In addition, we did not find a significant difference in the plasma migration inhibitory factor levels between the ST elevated myocardial infarction and NST-elevated myocardial infarction subgroups.

DISCUSSION

The circulating concentrations of migration inhibitory factor were significantly increased in acute myocardial infarction patients, whereas the soluble E-selectin levels were similar between acute myocardial infarction patients and control subjects. Our results suggest that migration inhibitory factor may play a role in the atherosclerotic process.

Assessment of the E-selectin rs5361 (561A>C) polymorphism and soluble protein concentration in acute coronary syndrome: association with circulating levels

Introduction. The acute coronary syndrome (ACS) is a complex disease where genetic and environmental factors are involved. E-selectin gene is a candidate for ACS progression due to its contribution in the inflammatory process and endothelial function. The rs5361 (561A>C) polymorphism in the E-selectin gene has been linked to changes in gene expression, affinity for its receptor, and plasmatic levels; therefore it is associated with an increased risk of cardiovascular disease. The aim of this study was to determine the association of the rs5361 polymorphism with ACS and to measure serum levels of soluble E-selectin (sE-selectin). Materials and Methods. 283 ACS patients and 205 healthy subjects (HS) from Western Mexico were included. The polymerase chain reaction-restriction fragment length polymorphism was used to determine the rs5361 polymorphism. The sE-selectin levels were measured by enzyme-linked immunosorbent assay. Results. Neither genotype nor allele frequencies of the rs5361 polymorphism showed statistical differences between groups. The sE-selectin levels were significantly higher in ACS patients compared to HS (54.58 versus 40.41 ng/ml, P = 0.02). The C allele had no effect on sE-selectin levels. Conclusions. The rs5361 E-selectin gene polymorphism is not a susceptibility marker for ACS in Western Mexico population. However, sE-selectin may be a biological marker of ACS.

Inflammatory biomarkers for predicting cardiovascular disease

The pathology of cardiovascular disease (CVD) is complex; multiple biological pathways have been implicated, including, but not limited to, inflammation and oxidative stress. Biomarkers of inflammation and oxidative stress may serve to help identify patients at risk for CVD, to monitor the efficacy of treatments, and to develop new pharmacological tools. However, due to the complexities of CVD pathogenesis there is no single biomarker available to estimate absolute risk of future cardiovascular events. Furthermore, not all biomarkers are equal; the functions of many biomarkers overlap, some offer better prognostic information than others, and some are better suited to identify/predict the pathogenesis of particular cardiovascular events. The identification of the most appropriate set of biomarkers can provide a detailed picture of the specific nature of the cardiovascular event. The following review provides an overview of existing and emerging inflammatory biomarkers, pro-inflammatory cytokines, anti-inflammatory cytokines, chemokines, oxidative stress biomarkers, and antioxidant biomarkers. The functions of each biomarker are discussed, and prognostic data are provided where available.

Morphine postconditioning attenuates ICAM-1 expression on endothelial cells

The purpose of this study is to determine 1) whether morphine post condition (MPostC) can attenuate the intercellular adhesion molecules-1 (ICAM-1) expression after reoxygenation injury and 2) the subtype(s) of the opioid receptors (ORs) that are involved with MPostC. Human umbilical vein endothelial cells (HUVECs) were subjected to 6 hr anoxia followed by 12 hr reoxygenation. Three morphine concentrations (0.3, 3, 30 µM) were used to evaluate the protective effect of MPostC. We also investigated blockading the OR subtypes' effects on MPostC by using three antagonists (a µ-OR antagonist naloxone, a κ-OR antagonist nor-binaltorphimine, and a δ-OR antagonist naltrindole) and the inhibitor of protein kinase C (PKC) chelerythrine. As results, the ICAM-1 expression was significantly reduced in the MPostC (3, 30 µM) groups compared to the control group at 1, 6, 9, and 12 hours reoxygenation time. As a consequence, neutrophil adhesion was also decreased after MPostC. These effects were abolished by co administering chelerythrine, nor-binaltorphimine or naltrindole, but not with naloxone. In conclusion, it is assumed that MPostC could attenuate the expression of ICAM-1 on endothelial cells during reoxygenation via the κ and δ-OR (opioid receptor)-specific pathway, and this also involves a PKC-dependent pathway.

A sensitive assay for the quantification of integrin-mediated adhesiveness of human stem cells and leukocyte subpopulations in whole blood

Adhesion of leukocytes is an early step in the formation of adaptive or innate immunity. In chronic inflammatory pathologies like atherosclerosis, regulation of adhesiveness is pivotal for the accumulation of leukocytes within the vessel wall. Therefore, the quantification of adhesion is crucial for the understanding and monitoring of immune responses in patients. However, so far, functional analysis of leukocyte adhesion has been time consuming and required prior purification of cell populations from peripheral blood. This reduced the number of samples and cell populations that could be analysed from limited patient material. Here, we introduce a novel method involving rapid quantification of integrin-mediated leukocyte adhesion in human whole blood using flow cytometry. The quantification relies on soluble multivalent immunocomplexes and is thus called "ligand-complex-based adhesion assay" (LC-AA). LC-AA evaluates both integrin affinity and avidity in T-cells, NK-cells and monocytes from as little as 20 mul of whole blood. In marked contrast to T-cells and NK-cells, unstimulated monocytes show non-blockable background binding of the complexes. Therefore, for this subset only, the stimulation-induced integrin activation is measurable. With the LC-AA, for the first time, measurement of adhesiveness of extremely rare cell populations like CD34+ peripheral blood stem cells can be assessed in the absence of prior purification steps. Finally, the small blood volumes needed for adhesion analysis with the LC-AA allow the evaluation of multiple cell subpopulations in large sample collectives, e.g. required in clinical studies.

Gliclazide treatment lowers serum ICAM-1 levels in poorly controlled type 2 diabetic patients

OBJECTIVE

To investigate the potential effect of gliclazide on serum ICAM-1 (intercellular adhesion molecule-1) and VCAM-1 (vascular cell adhesion molecule-1) levels in poorly controlled type 2 diabetic patients.

PATIENTS AND METHODS

The study included 104 patients, randomly divided into two groups. Group A comprised 53 patients (26 men) treated with gliclazide with a mean age of 67.5+/-9.9 years, a mean diabetes duration of 13.4+/-5.4 years and a mean HbA1c of 8.6+/-1.1%. Group B comprised 51 patients (25 men) treated with glibenclamide with a mean age of 66.4+/-10.9 years, a mean diabetes duration of 13.2+/-6.1 years and a mean HbA1c of 8.4+/-1.3%. A third group of 30 healthy controls (15 men) with a mean age of 63.3+/-10.4 years was also included. Serum levels of ICAM-1 and VCAM-1 were measured at the beginning of the study and after six months of treatment.

RESULTS

Pretreatment serum ICAM-1 and VCAM-1 levels did not differ between groups A and B, while they were significantly higher (P=0.0001) than in healthy controls. No significant difference in HbA1c, body mass index, blood pressure control and lipid profile between the two groups was observed after the sixth month of treatment. In group A, serum ICAM-1 levels after six months of treatment were significantly reduced from 623.12+/-61.17 ng/ml to 370.14+/-49.92 ng/ml (P=0,01), while no reduction was found in VCAM-1 levels. In group B, no reduction was found in serum ICAM-1 and VCAM-1 levels after the end of the study.

CONCLUSIONS

Our results suggest that gliclazide treatment reduces serum ICAM-1 levels in poorly controlled type 2 diabetic patients. This reduction is independent of the hypoglycaemic action of gliclazide.

Circulating markers of endothelial function in cardiovascular disease

Endothelial dysfunction is a key event in cardiovascular disease. Measurement of endothelial dysfunction in vivo presents a major challenge, but has important implications since it may identify the clinical need for therapeutic intervention, specifically in primary prevention. Several biological markers have been used as indicators of endothelial dysfunction. The soluble adhesion molecules sICAM-1 and sVCAM-1 lack specificity and are increased in inflammatory processes. Both markers are increased in coronary artery disease. sICAM-1 level predicts the risk for cardiovascular disease or diabetes mellitus in healthy individuals. sE-selectin is specific for the endothelium and is increased in coronary artery disease and diabetes mellitus. sE-selectin is also associated with diabetic risk. The endothelium-specific marker, soluble thrombomodulin, is associated with severity of coronary artery disease, stroke or peripheral occlusive arterial disease and is not increased in healthy or asymptomatic subjects. Interestingly, thrombomodulin decreases during treatment of hypercholesterolemia or hyperhomocysteinemia. In contrast, von Willebrand factor is the best endothelial biomarker and predicts risk for ischemic heart disease or stroke.

Systemic inflammatory markers in acute coronary syndrome: association with cardiovascular risk factors and effect of early lipid lowering

BACKGROUND

Evidence for statin therapy in prevention of coronary artery disease is overwhelming. In spite of theoretical benefits, any additional advantage of its early introduction in the management of acute coronary syndrome is, however, uncertain. We therefore investigated differences between plasma levels of the systemic inflammatory markers intercellular adhesion molecule-1, vascular cell adhesion molecule-1, E-selectin, C-reactive protein and interleukin-6 in patients presenting with unstable angina or acute myocardial infarction, and assessed whether the 30-day levels of these markers are influenced by early instigation of the HMG-CoA reductase inhibitor pravastatin.

MATERIALS AND METHODS

170 (134 male) patients presenting with acute coronary syndrome, but without previous statin therapy, participated. Blood was taken within 24 h of onset of ischaemic pain and again at 30 days. In all, 87 (71 male) participants were treated with pravastatin (20-40 mg daily) and 83 (63 male) with a matched placebo.

RESULTS

At presentation, interleukin-6 was higher in males than in females (P=0.008) and lower in those with a pre-existing history of myocardial infarction (P=0.038). C-reactive protein and interleukin-6 were greater in myocardial infarction, but this difference was lost at 30 days. Thirty-day changes in all parameters were inversely related to level at presentation but not to treatment with pravastatin. Hypertension (P=0.011) and smoking (P=0.042) were associated with elevation of C-reactive protein with no difference between unstable angina or acute myocardial infarction. The effect of these individual factors was cumulative.

CONCLUSIONS

Interleukin-6 was greater in acute myocardial infarction than in unstable angina; E-selectin was positively associated with a previous myocardial infarction and inversely related to age. We found no effect of early introduction of pravastatin on systemic inflammatory markers 30 days after acute coronary syndrome.

C-Reactive Protein, Interleukin-6, and Soluble Adhesion Molecules as Predictors of Progressive Peripheral Atherosclerosis in the General Population

Background— The relationship between levels of circulating inflammatory markers and risk of progressive atherosclerosis is relatively undetermined. We therefore studied inflammatory markers as predictors of peripheral atherosclerotic progression, measured by the ankle-brachial index (ABI) at 3 consecutive time points over 12 years.

Methods and Results— The Edinburgh Artery Study is a population cohort study of 1592 men and women aged 55 to 74 years. C-reactive protein (CRP), interleukin-6 (IL-6), intercellular adhesion molecule-1 (ICAM-1), vascular adhesion molecule-1 (VCAM-1), and E-selectin were measured at baseline. Valid ABI measurements were obtained on 1582, 1081, and 813 participants at baseline and 5-year and 12-year follow-up examinations, respectively. At baseline, a significant trend was found between higher plasma levels of CRP ( P ≤0.05) and increasing severity of peripheral arterial disease (PAD), after adjustment for baseline cardiovascular risk factors. IL-6 at baseline ( P ≤0.001) was associated with progressive atherosclerosis at 5 years (ABI change from baseline), and CRP ( P ≤0.01), IL-6 ( P ≤0.001), and ICAM-1 ( P ≤0.01) were associated with changes at 12 years, independently of baseline ABI, cardiovascular risk factors, and baseline cardiovascular disease. Only IL-6 independently predicted ABI change at 5 years ( P ≤0.01) and 12 years ( P ≤0.05) in analyses of all inflammatory markers simultaneously and adjusted for baseline ABI, cardiovascular risk factors, and cardiovascular disease at baseline.

Conclusions— These findings suggest that CRP, IL-6, and ICAM-1 are molecular markers associated with atherosclerosis and its progression. IL-6 showed more consistent results and stronger independent predictive value than other inflammatory markers.

Serum soluble lectin-like oxidized low-density lipoprotein receptor-1 levels are elevated in acute coronary syndrome: a novel marker for early diagnosis

BACKGROUND

Markers of cardiac injury, including troponin-T (TnT), are used to diagnose acute coronary syndrome (ACS); however, markers for plaque instability may be more useful for diagnosing ACS at the earliest stage. Lectin-like oxidized LDL receptor-1 (LOX-1) appears to play crucial roles in the pathogenesis of atherosclerotic plaque rupture and ACS onset. LOX-1 is released in part as soluble LOX-1 (sLOX-1) by proteolytic cleavage.

METHODS AND RESULTS

We examined serum sLOX-1 levels in 521 patients, consisting of 427 consecutive patients undergoing coronary angiography, including 80 ACS patients, 173 symptomatic coronary heart disease patients, 122 patients with significant coronary stenosis without ischemia, and 52 patients without apparent coronary atherosclerosis plus 34 patients with noncardiac acute illness and 60 patients with noncardiac chronic illness. Time-dependent changes in sLOX-1 and TnT levels were analyzed in an additional 40 ACS patients. Serum sLOX-1 levels were significantly higher in ACS than the other groups and were associated with ACS as shown by multivariable logistic regression analyses. Given a cutoff value of 1.0 ng/mL, sLOX-1 can discriminate ACS from other groups with 81% and 75% of sensitivity and specificity, respectively. sLOX-1 can also discriminate ACS without ST elevation or abnormal Q waves and ACS without TnT elevation from non-ACS with 91% and 83% of sensitivity, respectively. Peak values of sLOX-1 in ACS were observed earlier than those of TnT.

CONCLUSIONS

sLOX-1 appears to be a useful marker for early diagnosis of ACS.

Adhesion molecules and atherosclerosis

One early phase of atherosclerosis involves the recruitment of inflammatory cells from the circulation and their transendothelial migration. This process is predominantly mediated by cellular adhesion molecules, which are expressed on the vascular endothelium and on circulating leukocytes in response to several inflammatory stimuli. Selectins (P, E and L) and their ligands (mainly P-selectin ligand) are involved in the rolling and tethering of leukocytes on the vascular wall. Intercellular adhesion molecules (ICAMs) and vascular cell adhesion molecules (VCAM-1), as well as some of the integrins, induce firm adhesion of inflammatory cells at the vascular surface, whereas platelet endothelial cellular adhesion molecules (PECAM-1) are involved in extravasation of cells from the blood compartment into the vessel and underlying tissue. For most of the cellular adhesion molecules, except integrins, soluble forms have been identified in the circulation although their origins are not fully understood. Several lines of evidence support a crucial role of adhesion molecules in the development of atherosclerosis and plaque instability. Expression of VCAM-1, ICAM-1 and L-selectin has been consistently observed in atherosclerotic plaques. There is accumulating evidence from prospective studies for a predictive role of elevated circulating levels of sICAM-1 in initially healthy people, and of sVCAM-1 in patients at high risk or with overt CAD. A large number of common polymorphisms has been identified in the genes encoding the different adhesion molecules, but studies investigating their relationship either with soluble forms or with CAD are still sparse and often based on small samples. Further research is needed to firmly establish the potential clinical and therapeutic utilities of (soluble) adhesion molecules, but results in both fields hold the promise that in future, adhesion molecules might add information for clinical risk prediction and serve as therapeutic targets.

Cellular adhesion molecules and cardiovascular disease. Part II. Their association with conventional and emerging risk factors, acute coronary events and cardiovascular risk prediction

The role of cellular adhesion molecules in the patho-genesis of atherosclerosis has now been clearly demonstrated. Plasma levels of adhesion molecules, which have been shed from the cell surface, have also been associated with the presence of clinical atherosclerotic disease, cardiovascular risk factors and acute coronary syndromes. However, there is little consensus in the literature, including between the large well-designed population studies. This may be explained either by unrecognized confounding factors or, alternatively, by the unpredictable relationship between cell surface expression and activity of cellular adhesion molecules and their shedding into the plasma under different circumstances. Probably for the latter reasons, there is at present little evidence that the measurement of circulating adhesion molecules is likely to offer any additional benefit for individual patients above the assessment of conventional cardiovascular risk factors in the assessment of either the extent of, or future risk from, cardiovascular disease.

Usefulness of elevated levels of soluble vascular cell adhesion molecule-1 in predicting in-hospital prognosis in patients with unstable angina pectoris

To assess the in-hospital prognostic value of cellular adhesion molecules (CAMs), the levels of soluble CAMs were measured at admission in 114 patients with severe unstable angina. Patients with an eventful in-hospital course (death, nonfatal acute myocardial infarction, and recurrence of angina) had higher levels of soluble vascular cell adhesion molecule-1 than those without events (p = 0.01); this association was independent of classic risk factors and C-reactive protein.

Time course of plasma adhesion molecules in acute coronary syndromes

BACKGROUND

Atherosclerosis is an inflammatory process in which adhesion molecules play an intimate role in both the initiation and progression of lesions. It is postulated that they also play a role in the presentation of acute coronary syndromes and that plasma levels thereafter may be of potential prognostic significance. The stability of sample levels under different laboratory conditions is unknown.

METHODS

Stability of plasma levels was assessed in six healthy subjects under four different laboratory conditions. The time course of levels was studied in 57 patients with acute chest pain, 21 of non-cardiac aetiology, 23 unstable angina and 13 acute myocardial infarction, at mean times of 2.3, 8.2 and 17.3 h after the onset of pain. Samples were assayed for intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), P-selectin, E-selectin and C-reactive protein (CRP).

RESULTS

ICAM-1, VCAM-1, P-selectin and E-selectin levels did not differ under different laboratory conditions. Levels were similar at presentation in patients with acute chest pain of non-cardiac aetiology, unstable angina or acute myocardial infarction (median levels ICAM-1 269 microg/l, VCAM-1 379 microg/l, P-selectin 167 microg/l and E-selectin 53 microg/l). Levels did not change in the 24 h following the onset of pain. CRP levels did not differ at presentation between groups (median level 2.1 mg/l), but rose more than 12 h after the onset of pain in the group with acute myocardial infarction (P < 0.05).

CONCLUSION

Adhesion molecule levels are stable under normal laboratory sample handling conditions. Levels do not change in the 24 h following the onset of chest pain of non-cardiac or acute ischaemic aetiology.

Serum levels of selected adhesion molecules in patients with coronary artery disease

BACKGROUND

Adhesion molecules have been suggested as mediators of atherosclerotic inflammatory process. They may contribute to the pathogenesis of stable and unstable angina.

METHODS

The study group consisted of 59 patients with coronary artery disease: 27 patients with stable exertional angina (group A), 32 patients with unstable angina (group B). 20 healthy persons acted as controls (group C). Serum levels of soluble Intercellular Adhesion Molecule 1 (sICAM-1), Vascular Cell Adhesion Molecule 1 (sVCAM-1), sE-selectin, sP-selectin were measured both before and after the treadmill ECG stress test in groups A and C. In group B the measurements were carried out at 6, 24, and 48 hours following an episode of chest pain.

RESULTS

There were no differences between the baseline serum levels of adhesion molecules as determined in groups A and C. In patients with stable angina, the post-exercise concentrations of sE-selectin were significantly higher (68.8+/-29 ng/ml) in comparison to both baseline- (38.7+/-15 ng/ml), and group C-values (pre-exercise: 35.1+/-16; post-exercise: 49.9+/-15 ng/ml). In unstable patients, serum sP-selectin (190.1+/-99 ng/ml) and sVCAM-1 levels (1359+/-299 ng/ml) were higher when compared to those found in groups A (142.3+/-24; 962+/-352 ng/ml, respectively) and C (136.4+/-33; 851+/-168 ng/ml, respectively).

CONCLUSIONS

Serum levels of soluble adhesion molecules in patients with stable angina are comparable to those of healthy persons. Stress test-induced increase of sE-selectin concentration may reflect endothelial response to exercise. Unstable angina is characterized by significant elevation of sP-selectin and sVCAM-1 serum levels which seems to be related to enhanced platelets and leukocytes activation.

Elevated soluble cellular adhesion molecules in subjects with low HDL-cholesterol

The purpose of this study was to investigate whether the expression of cellular adhesion molecules (CAMs) is enhanced in individuals with low HDL cholesterol (HDL-C). Plasma levels of soluble vascular cell adhesion molecule-1 (sVCAM-1), intercellular adhesion molecule-1 (sICAM-1), and E-selectin (sE-selectin) were measured in subjects with low (below the 10th percentile for the Italian population), average, or high (above the 90th percentile) HDL-C. Average sICAM-1 and sE-selectin levels were significantly higher in two groups of 65 individuals with low HDL levels, either hyperlipidemic (320.5+/-16.0 and 61.4+/-3.5 ng/mL) or normolipidemic (309.6+/-13.0 and 60.0+/-2.7 ng/mL), than in subjects with average HDL levels, either hyperlipidemic (267.0+/-10.1 and 50.4+/-2.8 ng/mL) or normolipidemic (257.9+/-5.4 and 51.1+/-2.4 ng/mL), or with high HDL levels (254.8+/-10.2 and 52.5+/-3.2 ng/mL). No significant difference was found in the plasma sVCAM-1 concentration. HDL-C was inversely correlated with sICAM-1 and sE-selectin in the low-HDL subjects (r(2)=0.087 and 0.035, P=0.0007 and 0.033, respectively), but not in individuals with normal or elevated HDL-C (r(2)=0.012 and 0.006). A fenofibrate-induced increase of HDL-C in 20 low-HDL subjects was associated with a significant reduction of plasma sICAM-1 and sE-selectin concentrations. An increased CAMs expression may be a mechanism by which a low plasma HDL level promotes atherogenesis and causes acute atherothrombotic events.

Inflammation in acute coronary syndromes

Extensive evidence supports a pathogenic role for both local and systemic inflammation in acute coronary syndromes. However, several important questions remain unanswered. Is the observed inflammatory process a precursor or a consequence of coronary plaque rupture? Is the inflammatory component of unstable coronary disease a potential therapeutic target? Finally, do infectious agents have a pathogenic role in coronary atherosclerosis and acute coronary syndromes?

Levels of soluble E-selectin and ICAM-1 in the coronary circulation of patients with stable coronary artery disease: association with the severity of coronary atherosclerosis

The recruitment of circulating leukocytes to atherosclerotic sites is mediated by a family of adhesion molecules. The objective of the present study was to evaluate the relationship between circulating adhesion molecule levels in the coronary circulation and the severity of coronary atherosclerosis in patients with stable coronary artery disease. The subjects were 79 patients undergoing coronary angiography. According to the severity of coronary atherosclerosis as assessed by the Gensini Score (GS) of the left coronary artery, they were classified into three groups: group C (no organic stenosis, score 0, n = 14), group M (mild organic stenosis, score 1-13, n = 39) and group S (severe organic stenosis, score > or = 14, n = 26). Blood samples were taken from the aorta (Ao) and coronary sinus (CS), and plasma levels of soluble E-selectin (sE-selectin) and soluble intercellular adhesion molecule-1 (sICAM-1) were measured by enzyme-linked immunosorbent assay. These levels were then compared between groups. There were no significant differences in plasma sICAM-1 levels in the Ao or CS between the three groups. The difference in sICAM-1 levels between the CS and Ao (CS-Ao) also showed no significant difference. Plasma sE-selectin levels in both the Ao and CS were significantly higher in group S than in groups C and M (p < 0.05), but there were no significant differences in CS-Ao. There was a weak but significant correlation between the plasma levels of these adhesion molecules and the number of coronary risk factors present. Multivariate analysis showed that the number of coronary risk factors was the only positive predictor (p = 0.0048) of the GS; there was no association between the plasma level of either adhesion molecule and the GS. In patients with stable coronary artery disease, sICAM-1 plasma levels do not indicate the severity of coronary atherosclerosis, while sE-selectin plasma levels appear to reflect the severity of systemic rather than coronary atherosclerosis.

Elevated soluble P-selectin levels are associated with an increased risk of early adverse events in patients with presumed myocardial ischemia

BACKGROUND

Cell adhesion molecules (CAMs) play a pivotal role in the interactions between leukocytes, platelets, and vascular endothelium. Soluble CAMs (sCAMs) are shed from cell surfaces and reflect cellular activation. Elevated levels of sCAMs have been reported in the acute coronary syndromes. We hypothesized, therefore, that sCAMs might prove of prognostic value in patients with acute chest pain presumed to be the result of myocardial ischemia.

METHODS

One hundred twenty-six consecutive patients with chest pain, thought clinically to represent myocardial ischemia, were studied prospectively. Soluble intercellular adhesion molecule-1 (sICAM-1), vascular cell adhesion molecule-1 (sVCAM-1), E-selectin (sE-selectin) and P-selectin (sP-selectin) levels were assayed at presentation, as were cardiac troponin I (cTnI) and creatine kinase-MB(mass) (CK-MB(mass)). The primary study end point was the occurrence of a serious cardiac event (SCE) during the index admission or the subsequent 3 months.

RESULTS

sP-selectin and cTnI levels were significantly higher among patients who had an early SCE (P =.006 and P <.001, respectively). Both remained independently predictive (P <.001) in a multivariate regression equation. The other independent predictor was a history of vascular disease (P <.05). No other markers were significant predictors of early outcome.

CONCLUSION

Elevated sP-selectin levels, but not those of other sCAMs, are predictors of early adverse events in patients with chest pain presumed caused by myocardial ischemia. Their utility in predicting the outcome of individual patients is, however, limited.

Inhibition of phosphatidylinositol 3-kinase enhances mitogenic actions of insulin in endothelial cells

The concept of "selective insulin resistance" has emerged as a unifying hypothesis in attempts to reconcile the influence of insulin resistance with that of hyperinsulinemia in the pathogenesis of macrovascular complications of diabetes. To explore this hypothesis in endothelial cells, we designed a set of experiments to mimic the "typical metabolic insulin resistance" by blocking the phosphatidylinositol 3-kinase pathway and exposing the cells to increasing concentrations of insulin ("compensatory hyperinsulinemia"). Inhibition of phosphatidylinositol 3-kinase with wortmannin blocked the ability of insulin to stimulate increased expression of endothelial nitric-oxide synthase, did not affect insulin-induced activation of MAP kinase, and increased the effects of insulin on prenylation of Ras and Rho proteins. At the same time, this experimental paradigm resulted in increased expression of vascular cellular adhesion molecules-1 and E-selectin, as well as increased rolling interactions of monocytes with endothelial cells. We conclude that inhibition of the metabolic branch of insulin signaling leads to an enhanced mitogenic action of insulin in endothelial cells.

The influence of tobacco smoking on adhesion molecule profiles

Sequential interactions between several adhesion molecules and their ligands regulate lymphocyte circulation and leukocyte recruitment to inflammatory foci. Adhesion molecules are, therefore, central and critical components of the immune and inflammatory system. We review the evidence that tobacco smoking dysregulates specific components of the adhesion cascade, which may be a common factor in several smoking-induced diseases. Smoking causes inappropriate leukocyte activation, leukocyte-endothelial adhesion, and neutrophil entrapment in the microvasculature, which may help initiate local tissue destruction. Appropriate inflammatory reactions may thus be compromised. In addition to smoke-induced alterations to membrane bound endothelial and leukocyte adhesion molecule expression, which may help explain the above phenomena, smoking has a profound influence on circulating adhesion molecule profiles, most notably sICAM-1 and specific sCD44 variants. Elevated concentrations of soluble adhesion molecules may simply reflect ongoing inflammatory processes. However, increasing evidence suggests that specific soluble adhesion molecules are immunomodulatory, and that alterations to soluble adhesion molecule profiles may represent a significant risk factor for several diverse diseases. This evidence is discussed herein.

Therapeutic potential of monoclonal antibodies in myocardial reperfusion injury

While reperfusion therapy in myocardial infarction is associated with better short- and long-term outcomes, it paradoxically results in reperfusion injury mediated by interactions between leukocytes, endothelial cells, platelets, and the myocardium. Several surface receptors, adhesion molecules, and ligands have been shown to be important in the pathogenesis of myocardial reperfusion injury, and therapeutic strategies employing the use of monoclonal antibodies have been attempted against many of them. These have included monoclonal antibodies against activated complement 5 (C5a) to inhibit leukotaxis, monoclonal antibodies against P-selectin, P-selectin glycoprotein ligand (PSGL)-1, L-selectin and E-selectin to inhibit leukocyte rolling, and monoclonal antibodies against the Mac-1 (CD11b/CD18) receptor and intercellular adhesion molecule (ICAM)-1 to block firm adhesion of leukocytes to endothelial cells. In addition, although initially developed as an antiplatelet agent, the glycoprotein IIb/IIIa receptor antagonist abciximab shows significant ability to diminish or prevent reperfusion injury, presumably through its ability to block the Mac-1 receptor on leukocytes. Finally, monoclonal antibodies have also been tested against several cytokines and adhesion molecules implicated in so-called subacute endothelial activation, including interleukin-8 and vascular cell adhesion molecule (VCAM)-1. Studies in animals evaluating the use of monoclonal antibodies in reperfusion injury against various potential targets have largely been successful; however, studies in humans have been disappointing, underscoring the pitfalls of using animal models for the study of complex diseases. Based upon current knowledge, it is becoming clear that a successful strategy against reperfusion injury will require targeting several pathways at once, rather than attempting to block one final common pathway. In addition, inhibition of subacute endothelial activation through inhibition of transcription factors, namely nuclear factor (NF)-kappa B, may be a prerequisite to significantly reducing the extent of myocardial damage in this condition. The future of monoclonal antibodies in the overall strategy remains unclear. Newer small molecule inhibitors are also under development, and the eventual role of gene therapy remains to be elucidated.

Soluble adhesion molecules and prediction of coronary heart disease: a prospective study and meta-analysis

BACKGROUND

Previous studies have suggested that circulating concentrations of soluble adhesion molecules are useful predictors of risk of coronary heart disease (CHD). Larger studies are needed, however, to test this hypothesis.

METHODS

We measured serum concentrations of four soluble cell adhesion molecules (intercellular adhesion molecule-1 [ICAM-1], vascular cell adhesion molecule-1 [VCAM-1], E-selectin, and P-selectin) in the stored baseline serum samples of 643 men with coronary heart disease and 1278 controls nested in a prospective sutdy of 5661 men who were monitored for 16 years. We also did a meta-analysis of previous relevant studies to place our findings in context.

RESULTS

Concentrations of soluble adhesion molecules were significantly associated with one another, with other markers of inflammation, and with some classic coronary risk factors. For ICAM-1, the odds ratio for CHD was 1.68 (95% CI 1.32-2.14) in a comparison of men in the top third with those in the bottom third of baseline measurements after adjustments for age and town. This decreased to 1.11 (0.75-1.64) after adjustment for some classic coronary risk factors and indicators of socioeconomic status. For the three other cell adhesion molecules, the odds ratios for CHD, first adjusted for age and town only, and then additionally adjusted for other risk factors, were: VCAM-1: 1.26 (0.99-1.61) and 0.96 (0.66-1.40); E-selectin: 1.27 (1.00-1.61) and 1.13 (0.78-1.62); and P-selectin: 1.23 (0.96-1.56) and 1.20 (0.81-1.76).

INTERPRETATION

The measurement of these adhesion molecules is unlikely to add much predictive information to that provided by more established risk factors.

Plasma levels of soluble cellular adhesion molecules in patients with arterial hypertension. Correlations with plasma endothelin-1

Background: Several reports have shown that circulating, soluble cellular adhesion molecules and endothelin-1 (ET-1) are implicated in the pathophysiological events of atherosclerosis and may reflect the endothelial dysfunction characterizing this disorder. Methods: To evaluate the expression of these factors in arterial hypertension (AH), we measured plasma levels of soluble intercellular adhesion molecule-1 (sICAM-1), soluble vascular cell adhesion molecule-1 (sVCAM-1), soluble P-selectin (sP-selectin), and ET-1 in 60 untreated patients with mild to moderate AH (hypercholesterolemic: n=31, normocholesterolemic: n=29) and 30 sex- and age-matched normocholesterolemic normotensive controls. Results: Hypertensive patients exhibited significantly higher levels of sICAM-1 (234+/-21 vs. 187+/-12 ng/ml, P<0.005), sVCAM-1 (681+/-42 vs. 589+/-23 ng/ml, P<0.005), sP-selectin (89+/-17 vs. 55+/-11 ng/ml, P<0.01) and ET-1 (6.2+/-0.7 vs. 2.4+/-0.3 pg/ml, P<0.01) than did normotensive controls. The normocholesterolemic hypertensives had lower levels of sICAM-1, sVCAM-1 (P<0.01), sP-selectin and ET-1 (P<0.05) than hypercholesterolemic hypertensives, but higher levels than normotensive controls (P<0.05). In hypertensives, plasma ET-1 was significantly correlated with mean arterial pressure (r=0.51, P<0.03) and sICAM-1 levels (r=0.64, P<0.01). In hypercholesterolemic hypertensives, LDL cholesterol was also significantly correlated with plasma levels of sICAM-1 (r=0.53, P<0.04) and sP-selectin (r=0.41, P<0.05). Conclusions: Plasma levels of soluble cellular adhesion molecules are elevated in hypertensive patients in comparison to normotensive controls and may be related to plasma ET-1 activity. The coexistence of hypercholesterolemia may enhance the plasma soluble adhesion molecule activity induced by AH.

Adhesion molecules in different treatments of acute myocardial infarction

BACKGROUND

Tissue damage after ischemia and reperfusion involves leukocyte endothelial interactions mediated by cell adhesion molecules. This study was designed to determine the time course of soluble adhesion molecules in patients with acute myocardial infarction after attempted reperfusion by thrombolysis with tissue plasminogen activator (tPA) or streptokinase (SK), or percutaneous transluminal coronary angioplasty (PTCA).

METHODS

In 3 x 10 randomly selected patients with acute myocardial infarction undergoing thrombolysis with tPA or SK, or treated with PTCA, plasma concentrations of soluble L-selectin, P-selectin, E-selectin, intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and platelet endothelial cell adhesion molecule-1 (PECAM-1) were measured by enzyme-linked immunosorbent assay, 30 min and 1, 2, 4, 8, 12 and 24 hours after intervention.

RESULTS

After thrombolysis with tPA, soluble L-selectin concentrations were persistently depressed and soluble PECAM-1 concentrations were elevated, compared with controls, SK and PTCA. While soluble VCAM-1 concentrations did not differ within the first hours after interventions between the three groups, soluble VCAM-1 rose by 24 hours after tPA thrombolysis but did not increase after SK and PTCA treatment. Soluble ICAM-1 concentrations were consistently elevated after PTCA compared with controls and thrombolysed patients. Soluble E-selectin was depressed after tPA thrombolysis and PTCA in comparison with controls, while the SK group showed an increase throughout the observation period. Soluble P-selectin was increased after PTCA and SK lysis up to 8 hours after treatment compared with controls, but no significant differences could be found between treatment groups.

CONCLUSION

Adhesion molecules mediating leukocyte endothelial interactions are altered subsequent to postischemic reperfusion and by treatment with thrombolytic agents and angioplasty. The clinical relevance of these biological changes remains to be determined.

Increased endothelial injury in septic patients with coronary artery disease

STUDY OBJECTIVE

Recently, it was proposed that soluble intercellular adhesion molecule (sICAM)-1 plasma levels may allow subgroup identification of patients at risk for cardiovascular complications during sepsis. However, the impact of preexisting coronary artery disease (CAD) on these results has not yet been tested. The aim of this study was to investigate whether plasma levels of adhesion molecules, nitric oxide, and cytokines differ between septic patients with or without preexisting CAD.

DESIGN

Prospective study.

SETTING

Surgical ICU.

PATIENTS

Forty-four septic patients, 24 of whom met the criteria of CAD.

MEASUREMENT

Hemodynamic measurements were performed and blood samples were taken within 12 h after onset of sepsis (early sepsis) and again 72 h thereafter (late sepsis). Soluble adhesion molecules and cytokines were determined using commercially available enzyme-linked immunosorbent assay kits, cyclic guanosinomonophosphate (cGMP) by competitive radioimmunoassay, and nitrite/nitrate photometrically by Griess reaction.

RESULTS

In CAD patients, sICAM-1 (p < 0.02) was significantly elevated in early and late sepsis, whereas soluble endothelial-linked adhesion molecule (sE-selectin; p < 0.01) and cGMP (p < 0.03) were only increased in late sepsis. Oxygen consumption did not significantly differ between groups. Oxygen delivery and mixed venous oxygen saturation during early and late sepsis were significantly diminished and the oxygen extraction ratio significantly increased in the CAD group (p < 0.05).

CONCLUSIONS

Increased endothelial injury may be indicated by the elevated levels of sICAM-1, sE-selectin, and cGMP in septic patients with preexisting CAD. These parameters, however, failed to serve as predictors for unknown CAD or chances for survival in early sepsis.

Relationship between intracoronary and peripheral expression of soluble cell adhesion molecules

BACKGROUND

Elevated levels of soluble cell adhesion molecules (sCAMs) have been reported in various coronary artery disease processes. The principle stimulus for expression of sCAMs is believed to be an inflamed atherosclerotic plaque within the coronary vessel. The relationship between levels of sCAMs in the coronary circulation and the peripheral circulation has not been defined. The primary aim of this study was to define the relationship between levels of sCAMs sampled from the systemic circulation and from the coronary circulation. We also set out to document the acute expression of soluble CAMs following coronary angioplasty with or without stent implantation.

METHODS

The coronary sinus was cannulated in patients undergoing LAD angioplasty. Samples were drawn from left coronary ostium (LCO) and coronary sinus (CS) and femoral vein simultaneously before, immediately after and 4 h after the PTCA procedure. Levels of sICAM-1, sVCAM-1, sE-selectin and sP-selectin were measured using ELISA technique.

RESULTS

10 patients (7 male/3 female, 61+/-11 y) entered the study. There was no significant difference in the levels of sICAM-1, sVCAM-1, sE-selectin and sPselectin whether sampled from left coronary ostium, coronary sinus or femoral vein at all time points. There was no significant change in the acute expression of sICAM-1, sVCAM-1 and sE-selectin following coronary angioplasty. Levels of sP-selectin fell significantly during the PTCA procedure (142+/-7 ng/ml to 64+/-6 ng/ml, P<0.001) but then rose again after 4 h and returned toward baseline levels at 24 h.

CONCLUSION

Levels of soluble CAMs sampled in the systemic circulation directly reflect levels in the coronary circulation. Coronary angioplasty results in rapid fall in levels of sP-selectin which returns to normal within 24 h following the procedure.

Activation of NF kappa B and expression of ICAM-1 in ischemic-reperfused canine myocardium

Although redox-sensitive transcription factors, including nuclear factor kappa B (NF kappa B) and activator protein-1 (AP-1), have been shown to induce intercellular adhesion molecule-1 (ICAM-1) gene transcription in isolated cells, little is known about their involvement in the regulation of the ICAM-1 gene in vivo during ischemia-reperfusion. Anesthetized closed-chest dogs underwent 90 min coronary artery occlusion, followed by reperfusion for 0, 15, 30, 60, 180, or 360 min. Blood flow (fluorescent or radioactive microspheres), ICAM-1 protein expression (immunohistochemistry), ICAM-1 gene activation (Northern blotting), and nuclear DNA-binding activity of NF kappa B and AP-1 (electrophoretic mobility shift assays) were assessed in myocardial tissue samples. ICAM-1 protein was expressed constitutively on vascular endothelium, but expression levels decreased markedly during ischemia. Within 15 min reperfusion, endothelial ICAM-1 protein increased, associated with a rapid appearance of ICAM-1 mRNA. Activation of both NF kappa B and AP-1 occurred following ischemia-reperfusion, but did not coincide temporally with early post-reperfusion ICAM-1 gene induction. NF kappa B was activated during ischemia, when ICAM-1 mRNA was undetectable, and did not increase further until 60 min reperfusion, well after the increase in ICAM-1 mRNA had begun. Similarly, AP-1 did not increase until 60 min reperfusion. In non-ischemic myocardium, NF kappa B and AP-1 were both activated, but ICAM-1 mRNA did not appear until 6 h later. By immunohistology, NF kappa B (p65 subunit) and the c-Fos subunit of AP-1 were localized primarily in vascular endothelium. Reperfusion of ischemic myocardium is associated with very rapid ICAM-1 gene induction in the context of prior NF kappa B activation, without new activation of NF kappa B. In non-ischemic myocardium, ICAM-1 transcription begins hours after NF kappa B is activated. These findings support a role for NF kappa B in ICAM-1 induction in vivo, but suggest that other processes, such as oxygen-radical generation, may combine with NF kappa B to trigger an accelerated transcription of ICAM-1 following ischemia-reperfusion.

Insulin inhibits the expression of intercellular adhesion molecule-1 by human aortic endothelial cells through stimulation of nitric oxide

Intercellular adhesion molecule-1 (ICAM-1) is expressed by endothelial and other cell types and participates in inflammation and atherosclerosis. It serves as a ligand for leukocyte function-associated antigen-1 on leukocytes and is partially responsible for the adhesion of lymphocytes, granulocytes, and monocytes to cytokine-stimulated endothelial cells and the subsequent transendothelial migration. Its expression on endothelial cells is increased in inflammation and atherosclerosis. As it has been suggested that insulin and hyperinsulinemia may have a role in atherogenesis, we have now investigated whether insulin has an effect on the expression of ICAM-1 on human aortic endothelial cells (HAEC). HAEC were prepared from human aortas by collagenase digestion and were grown in culture. Insulin (100 and 1000 microU/mL) caused a decrease in the expression of ICAM-1 (messenger ribonucleic acid and protein) by these cells in a dose-dependent manner after incubation for 2 days. This decrease was associated with a concomitant increase in endothelial nitric oxide synthase (NOS) expression also induced by insulin. To examine whether the insulin-induced inhibition of ICAM-1 was mediated by nitric oxide (NO) from increased endothelial NOS, HAEC were treated with N(omega)-nitro-L-arginine, a NOS inhibitor. N(omega)-Nitro-L-arginine inhibited the insulin-induced decrease in ICAM-1 expression in HAEC at the messenger ribonucleic acid and protein levels. Thus, the inhibitory effect of insulin on ICAM-1 expression is mediated by NO. We conclude that insulin reduces the expression of the proinflammatory adhesion molecule ICAM-1 through an increase in the expression of NOS and NO generation and that insulin may have a potential antiinflammatory and antiatherosclerotic effect rather than a proatherosclerotic effect.

Circulating adhesion molecules and neutral endopeptidase enzymuria in patients with urolithiasis and hydronephrosis

OBJECTIVES

To measure the concentrations of adhesion molecules (intercellular adhesion molecule-1 ¿ICAM-1, E-selectin, and L-selectin) in the serum of patients with renal stones and patients with hydronephrosis caused by obstructive ureteral stones. Renal tubular enzymes were examined from their urine samples to evaluate whether neutral endopeptidase (NEP) behaved as traditional tubular enzyme markers (N-acetyl-beta-glucosaminidase ¿NAG and beta-galactosidase ¿beta-GAL) in their disease state.

METHODS

Three groups were studied. Group 1 included 15 normal volunteers, group 2 included 12 patients with ureteral stones and ipsilateral hydronephrosis, and group 3 included 17 patients with renal stones in one kidney without hydronephrosis or hydrocalycosis. A single, overnight fasting blood and urine sample was collected from each subject. Serum levels of ICAM-1, E-selectin, and L-selectin were measured by enzyme-linked immunosorbent assay. NEP, NAG, and beta-GAL were measured from urine samples, and the enzyme activities were expressed per gram of creatinine.

RESULTS

Serum levels of ICAM-1 were higher in groups 2 and 3 (522 +/- 95 and 329 +/- 42 ng/mL, respectively), but the differences were only significant between group 2 and group 1 (263 +/- 32 ng/mL) and group 2 and group 3 (P <0.05). Serum levels of L-selectin were lower in group 3 and were significantly different when compared with groups 1 and 2 (P <0. 05). The serum levels of E-selectin were not significantly different among these three groups. Urinary levels of NEP were lower in group 2, although the levels of NAG and beta-GAL were more elevated than in group 1.

CONCLUSIONS

Serum levels of ICAM-1 were elevated in patients with unilateral hydronephrosis caused by a ureteral stone, and E-selectin and L-selectin levels did not change significantly. These findings suggest that ICAM-1 may play a role in renal immune injury to ureteral obstruction. The urinary NEP values were lower in patients with hydronephrosis caused by ureteral stones, and the traditional lysosomal enzymes were increased. The lower urinary NEP values might suggest impairment of ipsilateral renal function. Renal stones per se resulted in no significant changes in serum adhesion molecule levels, although the levels of L-selectin were significantly decreased.

Microvascular response in patients with cardiogenic shock

OBJECTIVE

To examine the mechanisms contributing to decreased microvascular blood flow in cardiogenic shock by comparing patients with cardiogenic shock with critically ill controls and with patients with septic shock.

DESIGN

Prospective, consecutive entry of patients meeting the criteria for septic shock, cardiogenic shock, and critical illness without coexisting infection or shock.

SETTING

University hospital, medical intensive care unit, coronary care unit, and respiratory care unit.

PATIENTS

Eight patients with cardiogenic shock secondary to acute myocardial infarction, six critically ill controls, and six patients with septic shock.

MEASUREMENTS AND MAIN RESULTS

Forearm blood flow was measured at rest and during reactive hyperemia by venous air plethysmography. Red cell deformability was determined by filtration. Leukocyte aggregation was detected by the leukergy test. Neutrophil CD11b/CD18 expression and soluble intercellular adhesion molecule-1 levels were also measured. In cardiogenic shock, forearm arterial resistance was significantly increased at rest and during reactive hyperemia compared with controls and patients with septic shock. The response to reactive hyperemia was attenuated in cardiogenic and septic shock patients, as measured by the absolute change in forearm blood flow from baseline, which was significantly less as compared with controls (p < .01). The percent change in forearm blood flow during reactive hyperemia compared with forearm blood flow at rest was significantly lower in cardiogenic shock (60+/-10) and in septic shock (50+/-11) compared with controls at baseline (145+/-20; p < .01). Red cell deformability was significantly decreased in cardiogenic shock (1.2+/-0.2 mL/min; p < .05) and septic shock (1.1+/-0.2 mL/min; p < .05), compared with controls (1.8+/-0.1 mL/min). Neutrophil CD11b/CD18 expression, leukergy, and serum intercellular adhesion molecule-1 levels in cardiogenic shock patients were not significantly different from controls.

CONCLUSION

These data suggest that the response to reactive hyperemia is attenuated in cardiogenic shock. This appears to reflect increased vasoconstriction and an impaired capacity for vasodilation. Decreased erythrocyte deformability may also be important in limiting systemic microvascular flow. However, evidence supporting a role for neutrophil-endothelial cell interactions was not observed.

The acute influence of tobacco smoking on adhesion molecule expression on monocytes and neutrophils and on circulating adhesion molecule levels in vivo

Soluble adhesion molecules have been reported as risk markers of a wide range of human diseases and specific adhesion molecules may play a direct role in pathological processes. Serum soluble intercellular adhesion molecule-1 (sICAM-1) is known to be significantly elevated in smokers compared to non-smokers. We examined the acute effects of smoking a standard 2R1 research cigarette on the serum concentration of sICAM-1 and other circulating adhesion molecules (sP-selectin, sE-selectin, sL-selectin, sVCAM-1 and sPECAM-1) in heavy smokers (serum cotinine >/= 100 ng/ml), light smokers (serum cotinine </= 60 ng/ml) and non-smokers (serum cotinine </= 10 ng/ml) by ELISA. Adhesion molecule expression on the cell surface of monocytes and neutrophils in peripheral blood was examined by flow cytometry. The sICAM-1 concentration directly correlated to serum cotinine concentration (p= 0.047) and nicotine load (p= 0.033) in smokers and was significantly elevated compared to non-smokers (p= 0.037). Other than a decrease in the concentration of sP-selectin over 1 hour regardless of smoking, no significant temporal alterations of any adhesion molecule were observed following the smoking experience or in the non-smoking control group. No significant difference in surface expression of ICAM-1, CD18, PECAM-1 or L-selectin on peripheral monocytes or neutrophils was observed over a 1-hour period following smoking. These data suggest that the elevated concentration of sICAM-1 in smokers is not due to an immediate effect of smoking.

Elevated levels of soluble intercellular adhesion molecule-1 in the coronary circulation of patients with coronary organic stenosis and spasm

The cell surface expression of intercellular adhesion molecule-1 (ICAM-1) is upregulated following activation during inflammatory responses, mediating both cell migration and activation. The involvement of inflammation in unstable angina is suggested by the presence of activated circulating leukocytes. To examine whether plasma soluble ICAM-1 (sICAM-1) levels increase in the coronary circulation of patients with coronary organic stenosis and coronary spasm, plasma sICAM-1 levels were measured in the coronary sinus (CS) and the aortic root (Ao) simultaneously in 10 patients with 90% or more coronary narrowing and coronary spasm (coronary spastic angina (CSA) with organic stenosis), in 11 patients with coronary spasm and no significant coronary narrowing (CSA without organic stenosis), in 16 patients with stable exertional angina, and in 13 control subjects. The plasma sICAM-1 levels (ng/ml) in the CS increased in CSA with organic stenosis (230+/-26) as compared with CSA without organic stenosis (158+/-14), stable exertional angina (130+/-9) and control subjects (121+/-10) (p<0.01). The levels in the Ao also increased in CSA with organic stenosis (208+/-24) as compared with CSA without organic stenosis (149+/-13), stable exertional angina (130+/-11) and control subjects (121+/-10) (p<0.01). Furthermore, the plasma sICAM-1 levels were higher in the CS than in the Ao only in CSA with organic stenosis. These results suggest that activation of leukocytes occurs through the induction of ICAM-1 in the coronary circulation in the patients with CSA with organic stenosis.

Circulating adhesion molecules and severity of coronary atherosclerosis

BACKGROUND

Circulating leukocytes are recruited at atherosclerotic sites through a family of adhesion molecules. Circulating forms of adhesion molecules in peripheral blood can be quantified now.

OBJECTIVE

To evaluate the relationship between circulating adhesion molecules and severity of coronary atherosclerosis.

METHODS

Subjects included 81 patients undergoing diagnostic coronary angiography, 12 of whom had normal coronary arteries (control group). The remaining 69 patients with demonstrable coronary atherosclerosis were divided into two groups by use of Gensini scores, namely mild atherosclerosis (n = 36, Gensini score 1-20) and severe atherosclerosis (n = 33, Gensini score > 20). Serum levels of circulating intercellular adhesion molecule-1 (ICAM-1), vascular cellular adhesion molecule-1 (VCAM-1), and E-selectin of groups measured before angiography were compared.

RESULTS

Circulating levels of ICAM-1 in members of mild and severe atherosclerosis groups were significantly higher than those in members of the control group, whereas there was no significant difference among circulating levels of VCAM-1 in members of the three groups. Circulating levels of E-selectin in members of the mild atherosclerosis group were significantly higher than those in members of the severe atherosclerosis and control groups.

CONCLUSIONS

These findings suggest that E-selectin is related to the early stage, and ICAM-1 is related to the advanced stage, of coronary atherosclerosis. With progression of atherosclerosis, one-step adhesion by ICAM-1 could become more important than multistep adhesion involving E-selectin, ICAM-1, and VCAM-1. These molecules may serve as markers for severity of coronary atherosclerosis.

Soluble E-selectin is not a marker of unstable coronary plaque in serum of patients with ischemic heart disease

Increased level of soluble cell adhesion molecules may be a marker for atherosclerosis and/or reflect complication of the atherosclerotic plaque. To test whether expression of cell adhesion molecules is more pronounced in unstable versus stable coronary plaques, we measured the serum level of soluble E-selectin (sE-selectin) in 99 consecutive patients admitted to the hospital for acute coronary syndromes (ACS) and in 61 patients with chronic coronary artery disease (CAD) using a commercially available ELISA kit. We also measured the sE-selectin concentration in 20 sex- and age-matched subjects without clinical evidence of atherosclerosis, who served as controls. The mean sE-selectin level was higher in both groups of patients compared with controls (ACS, 35.0 +/- 23.4 ng/mL; chronic CAD, 32.9 +/- 21.0 ng/mL; controls, 14.5 +/- 6.6 ng/mL; one-way ANOVA, P = 0.001), but there was no difference between patients with ACS and chronic CAD. Furthermore, there was a trend (P = 0.08) toward a decrease in sE-selectin with an increase in the extent and severity of CAD. In patients with ACS, the in-hospital cardiac event rate was 8%. Although mean sE-selectin concentration tended to be higher in patients with (49.2 +/- 42.1 ng/mL) than in those without (33.8 +/- 21.3 ng/mL) in-hospital cardiac events, the difference was not significant. In 53 patients with ACS, C-reactive protein was measured and showed no correlation with the sE-selectin concentration. These findings show that although sE-selectin concentration is elevated in the presence of clinically relevant atherosclerosis, it does not further increase during the unstable phase of the disease, indicating that sE-selectin is not a reliable indicator of a complicated atherosclerotic plaque.

Role of cytokines and adhesion molecules in ischemia and reperfusion in patients with acute myocardial infarction

Although acute myocardial infarction (AMI) may involve both plaque rupture and ischemia-reperfusion injury, the pathogenesis of these phenomena is unclear. To elucidate the pathogenesis of AMI, serial measurements of platelet activating factor (PAF), interleukin-6 and cell adhesion molecules were made in patients with AMI. The PAF levels were measured upon hospital admission and at 24 and 72h in 8 patients with AMI. Serum levels of interleukin-6, soluble E-selectin (sE-selectin), soluble intercellular adhesion molecule-1 and soluble vascular cell adhesion molecule- 1 (sVCAM- 1) were measured upon admission and at 24 h and 4 weeks in 30 patients with AMI and 15 patients with stable effort angina. PAF levels were higher in patients with AMI than in normal volunteers; the increased levels lasting at least 72h. In contrast, interleukin-6 increased at 24h. sE-selectin was elevated at admission and sVCAM-1 increased later. sE-selectin levels upon admission in patients with additional ST-segment elevation after reperfusion were significantly higher than those in patients without ST-elevation. In patients with AMI, the time-course of changes in blood levels of cytokines varied according to the individual substances. Although it is unclear what is the precise role of each of the cytokines in the pathophysiology of AMI, sE-selectin may be possibly related to the reperfusion injury in the infarcted myocardium.

Early temporal expression of soluble cellular adhesion molecules in patients with unstable angina and subendocardial myocardial infarction

Inflammation is increasingly considered to be involved in the pathogenesis of acute coronary syndromes. We documented persistent elevation in the levels of soluble ICAM-1 and soluble VCAM-1 and a decrease in the levels of soluble E-selectin in the first 72 hours of acute presentation in patients with unstable angina and subendocardial myocardial infarction.

Soluble vascular cell adhesion molecule-1 and E-selectin in patients with acute myocardial infarction treated with thrombolytic agents

Twenty-three patients enrolled in th GUSTO-III study underwent serial measurements of soluble vascular cell adhesion molecule-1 (VCAM-1) and E-selectin by enzyme-linked immunosorbent assay at prespecified time intervals. Soluble VCAM-1, but not E-selectin levels, were increased in patients with acute myocardial infarction, indicating that VCAM-1 may serve as a marker of increased endothelial activation in acute myocardial infarction.

Attenuation of neutrophil and endothelial activation by intravenous morphine in patients with acute myocardial infarction

To investigate the effects of morphine on neutrophil and endothelial activation, we measured serum levels of intercellular adhesion molecule-1 (ICAM-1), L-selectin, and neutrophil endopeptidase 24.11 (NEP) in 38 patients with acute myocardial infarction (group 1) and 16 control subjects (group 2). In group 1, all the patients underwent blood sampling at initial presentation and 10 minutes later. Twenty of them had 3 mg of morphine administered intravenously immediately after the first sampling (group 1A) and the other 18 after a second sampling (group 1B). The serum levels of ICAM-1 and L-selectin were both significantly higher in groups 1A and 1B than in group 2. In group 1A, the ICAM-1 decreased significantly at second blood samplings (310 +/- 28 vs 368 +/- 30 ng/ml; p <0.001), whereas in group 1B there was no significant change in ICAM-1 (357 +/- 33 vs 359 +/- 26 ng/ml; p = NS). In group 1A, the L-selectin decreased significantly at second blood samplings (2.3 +/- 1.2 mg/L, p <0.001 vs baseline), whereas in group 1B there was no significant change in L-selectin (3.9 +/- 1.0 mg/L, p = NS vs baseline). There was no significant difference in baseline NEP activities between groups 1A and 1B (4.89 +/- 1.22 vs 5.14 +/- 1.57 nmol/mg protein; p = NS). However, the NEP activities at second blood samplings decreased significantly in group 1A (9.88 +/- 1.86 nmol/mg protein, p <0.001 vs baseline), whereas no significant changes were observed in group 1B (5.09 +/- 1.62 nmol/mg protein, p = NS vs baseline). In conclusion, morphine increased NEP activities and thus attenuated shedding of L-selectin and ICAM-1.

Soluble adhesion molecules reflect endothelial cell activation in ischemic stroke and in carotid atherosclerosis

BACKGROUND AND PURPOSE

Activation of endothelial cells and platelets plays an important role in the development of atherosclerosis and thrombotic disorders. Soluble adhesion molecules originating from these cells can be demonstrated in plasma. We hypothesized that elevated plasma concentrations of soluble P-selectin (sP-selectin), soluble intercellular adhesion mole-cule-1 (sICAM-1), soluble vascular cell adhesion molecule-1 (sVCAM-1), and soluble E-selectin (sE-selectin) can reflect activation of endothelial cells and/or platelets in acute ischemic stroke and in previously symptomatic internal carotid artery stenosis.

METHODS

Plasma was sampled from patients within 2 days of acute ischemic stroke (n = 28), from patients with a previous (> 1 week) transient or persistent ischemic neurological deficit associated with stenosis of the internal carotid artery (n = 34), and from control patients without a history of vascular disease (n = 34). Concentrations of sP-selectin, sICAM-1, sVCAM-1, and sE-selectin were measured by means of an enzyme-linked immunosorbent assay.

RESULTS

Compared with control subjects, sP-selectin and sE-selectin were significantly elevated in the acute stage of ischemic stroke (P < .0001 and P = .001, respectively) as well as in previously symptomatic carotid stenosis (P < .0001 and P = .0007). sICAM-1 and sVCAM-1 were not increased.

CONCLUSIONS

The elevated levels of sE-selectin indicate that endothelial cell activation occurs both in the acute stage of ischemic stroke and in previously symptomatic carotid atherosclerosis. Increased sP-selectin concentrations reflect endothelial cell activation as well but may also be caused by platelet activation.

Elevation of soluble adhesion molecules is associated with the severity of myocardial damage in acute myocardial infarction

In 20 patients with acute myocardial infarction, blood samples were taken to study the serial changes in the soluble intercellular adhesion molecule-1 (ICAM-1), vascular cellular adhesion molecule-1 (VCAM-1) and E-selectin. Results indicated that soluble ICAM-1 increased significantly and persisted throughout the study period; however, soluble E-selectin was significantly elevated only transiently and decreased rapidly thereafter, and the VCAM-1 did not increase during entire study period. There was a significant correlation between the levels of ICAM-1, E-selectin 6 hours after admission, and peak creatine kinase level; the levels of ICAM-1 and E-selectin were also positively correlated with total leukocyte count at admission.