Enhanced inflammatory response in patients with preinfarction unstable angina

Cardiovascular Inflammaging: Mechanisms and Translational Aspects

Aging is one of the major non-reversible risk factors for several chronic diseases, including cancer, type 2 diabetes, dementia, and cardiovascular diseases (CVD), and it is a key cause of multimorbidity, disability, and frailty (decreased physical activity, fatigue, and weight loss). The underlying cellular mechanisms are complex and consist of multifactorial processes, such as telomere shortening, chronic low-grade inflammation, oxidative stress, mitochondrial dysfunction, accumulation of senescent cells, and reduced autophagy. In this review, we focused on the molecular mechanisms and translational aspects of cardiovascular aging-related inflammation, i.e., inflammaging.

Management of inflammation in cardiovascular diseases

Cardiovascular disease is the leading cause of morbidity and mortality world-wide. Recently, the role of inflammation in the progression of diseases has significantly attracted considerable attention. In addition, various comorbidities, including diabetes, obesity, etc. exacerbate inflammation in the cardiovascular system, which ultimately leads to heart failure. Furthermore, cytokines released from specialized immune cells are key mediators of cardiac inflammation. Here, in this review article, we focused on the role of selected immune cells and cytokines (both pro-inflammatory and anti-inflammatory) in the regulation of cardiac inflammation and ultimately in cardiovascular diseases. While IL-1β, IL-6, TNFα, and IFNγ are associated with cardiac inflammation; IL-10, TGFβ, etc. are associated with resolution of inflammation and cardiac repair. IL-10 reduces cardiovascular inflammation and protects the cardiovascular system via interaction with SMAD2, p53, HuR, miR-375 and miR-21 pathway. In addition, we also highlighted recent advancements in the management of cardiac inflammation, including clinical trials of anti-inflammatory molecules to alleviate cardiovascular diseases.

High Sensitivity C-reactive Protein in Patients with Coronary Artery in-stent Restenosis: A Case-control Study

Background:

Inflammation plays a pivotal role in the pathogenesis of In-Stent Restenosis (ISR). High sensitivity C-reactive protein (hsCRP) is positively associated with major cardiovascular events.

Aim:

We aimed to investigate the hsCRP inflammatory response to Percutaneous Coronary Intervention (PCI) in Coronary Artery Disease (CAD) patients with coronary ISR vs. patients without ISR.

Methods:

This case-control study included 80 CAD patients previously treated with drug-eluting stent (DES) implantation. Patients had Coronary Angiography (CAG) because of chest pain or equivalent symptoms and were subdivided into 2 groups. Group A (n=40) included CAD patients with ISR. Group B (n=40) included age and gender-matched controls with CAD but without ISR. Serum hsCRP levels were obtained before PCI (baseline) and 8, 16, 24 h post-PCI.

Results:

At baseline (before intervention/CAG), the hsCRP level was increased in the ISR group compared with the No-ISR group (p=0.007). There were 36 (90%) patients in the ISR group who had a high hsCRP (>3 mg/L) compared with 25 (62.5%) patients in the No-ISR group. Also, there was a significant relationship between high hsCRP and the ISR. Patients with ISR had higher frequencies and percentages of elevated CRP than the no-ISR control group. This difference was maintained for all measurements, baseline, after 8, 16, and 24 h (p<0.05). Repeated measures analysis of variance (ANOVA) in the ISR group revealed that mean hsCRP differed significantly between serial measurements (p<0.001). In contrast, in the control group, the mean hsCRP did not differ significantly between the serial measurements (p=0.65).

Most of our patients (n=66, 82.5%) had 1-vessel CAD disease, and the left anterior descending (LAD) coronary artery was significantly affected in 46 patients (57.5%). Management of restenosis was accomplished mainly by stenting by DES in 29 patients (72.5%).

Conclusion:

Patients with ISR had substantially higher pre- and post-PCI hsCRP levels than the no-ISR controls. This difference was maintained up to 24h post-PCI. Conversely, the mean hsCRP did not significantly differ at the follow-up points for the controls without ISR.

Effect of atorvastatin on inflammatory markers in hemodialysis patients

Background

Cardiovascular disease is the commonest cause of death in patients with end-stage renal disease (ESRD) under maintenance hemodialysis. Dyslipidemia, oxidative stress, and low-grade inflammation with increased circulating cytokines are factors that increase the cardiovascular risk in patients with chronic kidney disease, in addition to traditional risk factors, such as obesity, hypertension, and diabetes. We aimed to investigate the possible anti-inflammatory effects of atorvastatin in prevalent hemodialysis patients. Fifty-three stable adult hemodialysis patients were assigned into two groups (a drug group and a control group). Patients in the drug group received 20 mg of atorvastatin daily for 6 months. Serum levels of highly sensitive C-reactive protein (hs-CRP) and interleukin-6 (IL-6) were measured in both groups at baseline and at the end of the study period.

Results

Atorvastatin therapy caused a statistically significant decrease in levels of hs-CRP but no change in levels of IL-6 after 6 months of therapy.

Conclusions

In addition to its favorable effect on lipid profile parameters, atorvastatin therapy can be considered as an effective and safe modality to overcome the problem of chronic inflammation encountered in end-stage renal disease patients.

Coronary inflammation: why searching, how to identify and treat it

Inflammation plays an important role in the development of atherosclerotic lesions. A variety of stimuli promote atherosclerosis, including increased LDL cholesterol in blood, exposure to tobacco, diabetes mellitus, hypertension, or rheological stress. Inflammatory cells have an established role in the growth of atherosclerotic lesions. Macrophages recognize and internalise ox-LDL to eventually become lipid-laden foam cells, the hallmark cellular component of atheroma. Infiltrating CD4-T cells have a role too, by interacting with ox-LDL and other antigens. Cytokines secreted by inflammatory cells stimulate smooth muscle cells migration whilst macrophages produce metalloprotease that lead to fibrous cap rupture. The necrotic debris of died macrophages and smooth muscle cells help to continue the inflammatory process. The inflammatory response can also directly activate platelets and promote thrombus formation at the surface of complicated coronary plaques. The CANTOS trial can be waived as an innovative study promoting a novel approach of personalized medicine. In patients with previous myocardial infarction, high-sensitivity C-reactive protein level of 2 mg and normal LDL level (<70 mg/dL), canakinumab a therapeutic monoclonal antibody targeting interleukin-1β, at a dose of 150 mg every 3 months, led to a significant reduction of the primary efficacy end point: nonfatal myocardial infarction, nonfatal stroke, or cardiovascular death at 48 months. Based on the CANTOS results, patients on statins and residual inflammatory risk as assessed by means of a high-sensitivity CRP >2 mg/l at baseline have a high risk of future cardiac events, comparable to that of statin-treated patients with suboptimal cholesterol LDL level. The inhibition of interleukin-1β by means of canakinumab, which is only one of many potential anti-inflammatory pathways, open new perspectives, showing that a selective inhibition of the inflammatory pathway may be beneficial in reducing cardiovascular risk. In a process of personalized medicine, there is need to accurately identify patients at high risk of events, to be treated with potent statins or anti-inflammatory drugs. Perhaps in the near future a more specific assessment of coronary inflammations, possibly obtained with imaging modalities (either invasive or non-invasive), will better select patients at risk of events. In this scenario, in the setting of secondary prevention, OCT may serve the scope of identifying vulnerable plaques with local aggregates of inflammatory cells. Future studies are needed to understand the clinical effectiveness of strategies based on invasive coronary assessment.

Systemic inflammatory activation in patients with acute coronary syndrome secondary to nonatherosclerotic spontaneous coronary artery dissection

OBJECTIVE

Pathological studies have suggested that local inflammation, particularly eosinophilic infiltration of the adventitia, could be related to nonatherosclerotic spontaneous coronary artery dissection (NA-SCAD). However, the role of systemic inflammation in the pathogenesis of NA-SCAD remains unknown. Our aim was to investigate systemic inflammatory activation in patients with an acute coronary syndrome (ACS) secondary to NA-SCAD.

METHODS

The institutional electronic medical database was reviewed, and 22 patients with NA-SCAD-ACS were identified after the review. Furthermore, 30 random patients with CAD-ACS and 30 random subjects without any history of CAD or ACS with demographic and clinical characteristics similar to those of NA-SCAD-ACS patients were identified from the institutional database to be included in the study.

RESULTS

Patients with NA-SCAD-ACS and those with CAD-ACS both had higher white blood cell and neutrophil counts than controls. Neutrophil-lymphocyte ratio (NLR) and C-reactive protein (CRP) levels were only significantly higher in the NA-SCAD-ACS group [2.01 (1.54-6.17) for NLR and 0.70 (0.13-2.70) for CRP] than in the controls [1.55 (1.27-2.13), p=0.03 for NLR and 0.15 (0.10-0.43), p=0.049 for CRP]; however, there were no differences between the NA-SCAD-ACS and CAD-ACS groups [1.91 (1.41-2.78) for NLR and 0.41 (0.09-1.10) for CRP, p>0.05 for both comparisons] regarding all tested parameters.

CONCLUSION

The degree of inflammatory activation in NA-SCAD-ACS patients was similar to, or even greater than, that in CAD-ACS patients; thus, suggesting a role of inflammation in the pathophysiology of NA-SCAD-ACS.

Can Specialized Pro-resolving Mediators Deliver Benefit Originally Expected from Fish Oil?

PURPOSE OF THE REVIEW

Fish oil (FO) supplementation has historically been used by individuals suffering from cardiovascular disease and other inflammatory processes. However, a meta-analysis of several large randomized control trials (RCTs) suggested FO conferred no benefit in reducing cardiovascular risk. Skeptics surmised that the lack of benefit was related to FO dose or drug interactions; therefore, the widely accepted practice of FO consumption was brought into question.

RECENT FINDINGS

Thereafter, Serhan et al. identified specialized pro-resolving mediators (SPMs) to be one of the bioactive components and mechanisms of action of FO. SPMs are thought to enhance resolution of inflammation, as opposed to classic anti-inflammatory agents which inhibit inflammatory pathways. Numerous diseases, including persistent Inflammation, immunosuppression, and catabolic syndrome (PICS), are rooted in a burden of chronic inflammation. SPMs are gaining traction as potential therapeutic agents used to resolve inflammation in cardiovascular disorders, inflammatory bowel disease, sepsis, pancreatitis, and acute respiratory distress syndrome (ARDS). This narrative reviews the history of FO and the various studies that made the health benefits of FO inconclusive, as well as an overview of SPMs and their use in specific disease states.

T cells and cytokines in atherogenesis

Recent findings suggest that inflammation plays a key role in atherosclerosis from the earliest stage of lesion initiation, to the ultimate complication of thrombosis. In patients who died because of acute coronary syndromes (ACS), coronary atherosclerotic plaques are characterized by the presence of macrophages, and to a lesser extent T-lymphocytes, at the immediate site of either plaque rupture or superficial erosion. The rupture-related inflammatory cells are activated, indicating ongoing inflammation. ACS patients are also characterized by activated circulating lymphocytes, monocytes and neutrophils, and by increased concentrations of proinflammatory cytokines and of the highly sensitive acute phase reactant C-reactive protein. Interestingly, an unusual subset of T cells, CD4+CD28null T cells, involved in vascular complication of rheumatoid arthritis because of their functional profile predisposing for vascular injury, are expanded in the peripheral blood and infiltrate the coronary lesions of ACS patients. The presence of activated T lymphocytes implies antigenic stimulation, but the nature of such antigen(s) remains to be investigated. Several autoantigens expressed in the atherosclerotic plaque, including oxidized LDL and heat shock proteins, and infectious agents are able to elicit an immune response. The inflammatory component is not localized to the ‘culprit’ plaque, but it is diffused to the entire coronary vascular bed, and involves also the myocardium.

Factors Associated With Plasma IL-6 Levels During HIV Infection

BACKGROUND

Elevated interleukin 6 (IL-6) levels have been linked to cardiovascular disease, cancer and death. Persons with human immunodeficiency virus (HIV) infection receiving treatment have higher IL-6 levels, but few data are available on factors associated with circulating IL-6.

METHODS

Participants in 3 trials with IL-6 measured at baseline were included (N = 9864). Factors associated with IL-6 were identified by linear regression. Demographic and HIV variables (nadir/entry CD4(+) cell count, HIV RNA level, antiretroviral therapy regimen) were investigated in all 3 trials. In the SMART (Strategies for Management of Anti-Retroviral Therapy) trial, CD4/CD8 ratio, smoking, comorbid conditions, serum lipids, renal function (estimated glomerular filtration rate [eGFR]), and educational level were assessed.

RESULTS

Demographics associated with higher IL-6 levels were older age and lower education, whereas black race was associated with lower IL-6. Higher HIV RNA levels were associated with higher IL-6 levels, and higher nadir CD4(+) cell counts with lower IL-6 levels. Compared with efavirenz, protease inhibitors were associated with higher and nevirapine with lower IL-6 levels. Smoking and all comorbid conditions were related to higher IL-6. IL-6 levels increased with decreasing eGFR and decreasing serum lipids.

CONCLUSIONS

Higher levels of IL-6 were associated with older age, nonblack race, higher body mass index, lower serum lipid levels, HIV replication, low nadir CD4(+) cell count, protease inhibitor use, comorbid conditions, and decreased eGFR. Multiple factors affect inflammation in HIV and should be considered in studies of IL-6 as a biomarker of clinical outcomes.

The role of notch in the cardiovascular system: potential adverse effects of investigational notch inhibitors

Targeting the Notch pathway is a new promising therapeutic approach for cancer patients. Inhibition of Notch is effective in the oncology setting because it causes a reduction of highly proliferative tumor cells and it inhibits survival of cancer stem cells, which are considered responsible for tumor recurrence and metastasis. Additionally, since Delta-like ligand 4 (Dll4)-activated Notch signaling is a major modulator of angiogenesis, anti-Dll4 agents are being investigated to reduce vascularization of the tumor. Notch plays a major role in the heart during the development and, after birth, in response to cardiac damage. Therefore, agents used to inhibit Notch in the tumors (gamma secretase inhibitors and anti-Dll4 agents) could potentially affect myocardial repair. The past experience with trastuzumab and other tyrosine kinase inhibitors used for cancer therapy demonstrates that the possible cardiotoxicity of agents targeting shared pathways between cancer and heart and the vasculature should be considered. To date, Notch inhibition in cancer patients has resulted only in mild gastrointestinal toxicity. Little is known about the potential long-term cardiotoxicity associated to Notch inhibition in cancer patients. In this review, we will focus on mechanisms through which inhibition of Notch signaling could lead to cardiomyocytes and endothelial dysfunctions. These adverse effects could contrast with the benefits of therapeutic responses in cancer cells during times of increased cardiac stress and/or in the presence of cardiovascular risk factor.

Association between resting heart rate and inflammatory biomarkers (high-sensitivity C-reactive protein, interleukin-6, and fibrinogen) (from the Multi-Ethnic Study of Atherosclerosis)

Heart rate (HR) at rest is associated with adverse cardiovascular events; however, the biologic mechanism for the relation is unclear. We hypothesized a strong association between HR at rest and subclinical inflammation, given their common interrelation with the autonomic nervous system. HR at rest was recorded at baseline in the Multi-Ethnic Study of Atherosclerosis, a cohort of 4 racial or ethnic groups without cardiovascular disease at baseline and then divided into quintiles. Subclinical inflammation was measured using high-sensitivity C-reactive protein, interleukin-6, and fibrinogen. We used progressively adjusted regression models with terms for physical activity and atrioventricular nodal blocking agents in the fully adjusted models. We examined inflammatory markers as both continuous and categorical variables using the clinical cut point of ≥3 mg/L for high-sensitivity C-reactive protein and the upper quartiles of fibrinogen (≥389 mg/dl) and interleukin-6 (≥1.89 pg/ml). Participants had a mean age of 62 years (SD 9.7), mean resting heart rate of 63 beats/min (SD 9.6) and were 47% men. Increased HR at rest was significantly associated with higher levels of all 3 inflammatory markers in both continuous (p for trend <0.001) and categorical (p for trend <0.001) models. Results were similar among all 3 inflammatory markers, and there was no significant difference in the association among the 4 racial or ethnic groups. In conclusion, an increased HR at rest was associated with a higher level of inflammation among an ethnically diverse group of subjects without known cardiovascular disease.

The Impact of Ischemic Time on the Predictive Value of High-Sensitivity C-Reactive Protein in ST-Segment Elevation Myocardial Infarction Patients Treated by Primary Percutaneous Coronary Intervention

BACKGROUND AND OBJECTIVES

The high-sensitivity C-reactive protein (hs-CRP), a marker of inflammation, has been known to be elevated in patients with coronary artery disease. However, there is controversy about the predictive value of hs-CRP after acute myocardial infarction (MI). Therefore, we evaluated the impact of ischemic time on the predictive value of hs-CRP in ST-segment elevation myocardial infarction (STEMI) patients who were treated by primary percutaneous coronary intervention (PCI).

SUBJECTS AND METHODS

We enrolled 5123 STEMI patients treated by primary PCI from the Korean Working Group in Myocardial Infarction and divided enrolled patients into four groups by symptom-to-balloon time (SBT) and level of hs-CRP (Group I: SBT <6 hours and hs-CRP <3 mg/L, Group II: SBT <6 hours and hs-CRP ≥3 mg/L, Group III: SBT ≥6 hours and hs-CRP <3 mg/L, and Group IV: SBT ≥6 hours and hs-CRP ≥3 mg/L). To evaluate the impact of ischemic time on the predictive value of hs-CRP in STEMI patients, we compared the cumulative cardiac event-free survival rate between these four groups.

RESULTS

The sum of the cumulative incidence of all-cause mortality and recurrence of MI was higher in Group IV than in the other groups. However, there was no significant difference among Group I, Group II, and Group III. The Cox-regression analyses showed that an elevated level of hs-CRP (≥3 mg/L) was an independent predictor of long-term cardiovascular outcomes only among late-presenting STEMI patients (p=0.017, hazard ratio=2.462).

CONCLUSION

For STEMI patients with a long ischemic time (≥6 hours), an elevated level of hs-CRP is a poor prognostic factor of long-term cardiovascular outcomes.

Enhanced SCAP glycosylation by inflammation induces macrophage foam cell formation

Inflammatory stress promotes foam cell formation by disrupting LDL receptor feedback regulation in macrophages. Sterol Regulatory Element Binding Proteins (SREBPs) Cleavage-Activating Protein (SCAP) glycosylation plays crucial roles in regulating LDL receptor and 3-hydroxy-3-methyl-glutaryl-CoA reductase (HMGCoAR) feedback regulation. The present study was to investigate if inflammatory stress disrupts LDL receptor and HMGCoAR feedback regulation by affecting SCAP glycosylation in THP-1 macrophages. Intracellular cholesterol content was assessed by Oil Red O staining and quantitative assay. The expression of molecules controlling cholesterol homeostasis was examined using real-time quantitative RT-PCR and Western blotting. The translocation of SCAP from the endoplasmic reticulum (ER) to the Golgi was detected by confocal microscopy. We demonstrated that exposure to inflammatory cytokines increased lipid accumulation in THP-1 macrophages, accompanying with an increased SCAP expression even in the presence of a high concentration of LDL. These inflammatory cytokines also prolonged the half-life of SCAP by enhancing glycosylation of SCAP due to the elevated expression of the Golgi mannosidase II. This may enhance translocation and recycling of SCAP between the ER and the Golgi, escorting more SREBP2 from the ER to the Golgi for activation by proteolytic cleavages as evidenced by an increased N-terminal of SREBP2 (active form). As a consequence, the LDL receptor and HMGCoAR expression were up-regulated. Interestingly, these effects could be blocked by inhibitors of Golgi mannosidases. Our results indicated that inflammation increased native LDL uptake and endogenous cholesterol de novo synthesis, thereby causing foam cell formation via increasing transcription and protein glycosylation of SCAP in macrophages. These data imply that inhibitors of Golgi processing enzymes might have a potential vascular-protective role in prevention of atherosclerotic foam cell formation.

Prognostic value of low and moderately elevated C-reactive protein in acute coronary syndrome: a 2-year follow-up study

BACKGROUND

The main goal of this study was to improve diagnostic and predictive value of low and moderately elevated C-reactive protein (CRP) in patients with acute coronary syndrome (ACS), related to noninvasive clinical parameters, in order to improve and prolong patient life with low or no additional costs.

MATERIAL/METHODS

A prospective, open clinical study was conducted at the University Hospital Split, Croatia with 112 patients with ACS and low or moderately elevated CRP (<3.0 mg/L). After diagnosing ACS, data on physical activity, alcohol consumption, and functional status were recorded. Anthropometric measurements were made. Blood and urine samples were taken for analyses. Electrocardiographic, ergometric, and echocardiographic testing was performed. A total of 72 parameters were monitored at the time of hospital admission in ACS patients to analyze which ones could predict disease outcome at the end of follow-up in patients with low or moderately elevated CRP. Patients were followed up for 2 years.

RESULTS

The variables that were predictive of major adverse cardiac events (MACE) within 2 years of ACS hospitalization were hemoglobin, fibrinogen, antithrombin III, cholesterol levels, brain natriuretic peptide, and microalbuminuria. ACS patients with CRP<3.0 mg/L had significantly higher risk of developing MACE within 2 years if ≥50% of the 8 key parameters were outside the reference values.

CONCLUSIONS

Major adverse cardiac events can be predicted in patients with acute coronary syndrome whose CRP values are low or moderately elevated.

Do we know enough about the immune pathogenesis of acute coronary syndromes to improve clinical practice?

Morbidities related to atherosclerosis, such as acute coronary syndromes (ACS) including unstable angina and myocardial infarction, remain leading causes of mortality. Unstable plaques are inflamed and infiltrated with macrophages and T lymphocytes. Activated dendritic cells interact with T cells, yielding predominantly Th1 responses involving interferon-gamma (IFN-γ) and tumour necrosis factor-alpha (TNF-α), while the role of interleukin 17 (IL-17) is questionable. The expansion of CD28nullCD4 or CD8 T cells as well as pattern recognition receptors activation (especially Toll-like receptors; TLR2 and TLR4) is characteristic for unstable plaque. Inflammation modifies platelet and fibrin clot characteristics, which are critical for ACS. Understanding of the inflammatory mechanisms of atherothrombosis, bridging inflammation, oxidative stress and immune regulation, will allow for the detection of subjects at risk, through the use of novel biomarkers and imaging techniques including intravascular ultrasound, molecular targeting, magnetic resonance imaging (MRI) and 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET). Moreover, understanding the specific inflammatory pathways of plaque rupture and atherothrombosis may allow for immunomodulation of ACS. Statins and anti-platelet drugs are anti-inflammatory, but importance of immune events in ACS warrants the introduction of novel, specific treatments directed either on cytokines, TLRs or inflammasomes. While the prime time for the introduction of immunologically inspired diagnostic tests and treatments for atherosclerosis have not come yet, we are closer than ever before to finally being able to benefit from this vast body of experimental and clinical evidence. This paper provides a comprehensive review of the role of the immune system and inflammation in ACS.

Cross-reacting antibacterial auto-antibodies are produced within coronary atherosclerotic plaques of acute coronary syndrome patients

Coronary atherosclerosis, the main condition predisposing to acute myocardial infarction, has an inflammatory component caused by stimuli that are yet unknown. We molecularly investigated the nature of the immune response within human coronary lesion in four coronary plaques obtained by endoluminal atherectomy from four patients. We constructed phage-display libraries containing the IgG1/kappa antibody fragments produced by B-lymphocytes present in each plaque. By immunoaffinity, we selected from these libraries a monoclonal antibody, arbitrarily named Fab7816, able to react both with coronary and carotid atherosclerotic tissue samples. We also demonstrated by confocal microscopy that this monoclonal antibody recognized human transgelin type 1, a cytoskeleton protein involved in atherogenesis, and that it co-localized with fibrocyte-like cells transgelin+, CD68+, CD45+ in human sections of coronary and carotid plaques. In vitro fibrocytes obtained by differentiating CD14+ cells isolated from peripheral blood mononuclear cells also interacted with Fab7816, thus supporting the hypothesis of a specific recognition of fibrocytes into the atherosclerotic lesions. Interestingly, the same antibody, cross-reacted with the outer membrane proteins of Proteus mirabilis and Klebsiella pneumoniae (and possibly with homologous proteins of other enterobacteriaceae present in the microbiota). From all the other three libraries, we were able to clone, by immunoaffinity selection, human monoclonal antibodies cross-reacting with bacterial outer membrane proteins and with transgelin. These findings demonstrated that in human atherosclerotic plaques a local cross-reactive immune response takes place.

Acute-phase serum amyloid A: perspectives on its physiological and pathological roles

Serum amyloid A (SAA), a protein originally of interest primarily to investigators focusing on AA amyloidogenesis, has become a subject of interest to a very broad research community. SAA is still a major amyloid research topic because AA amyloid, for which SAA is the precursor, is the prototypic model of in vivo amyloidogenesis and much that has been learned with this model has been applicable to much more common clinical types of amyloid. However, SAA has also become a subject of considerable interest to those studying (i) the synthesis and regulation of acute phase proteins, of which SAA is a prime example, (ii) the role that SAA plays in tissue injury and inflammation, a situation in which the plasma concentration of SAA may increase a 1000-fold, (iii) the influence that SAA has on HDL structure and function, because during inflammation the majority of SAA is an apolipoprotein of HDL, (iv) the influence that SAA may have on HDL's role in reverse cholesterol transport, and therefore, (v) SAA's potential role in atherogenesis. However, no physiological role for SAA, among many proposed, has been widely accepted. None the less from an evolutionary perspective SAA must have a critical physiological function conferring survival-value because SAA genes have existed for at least 500 million years and SAA's amino acid sequence has been substantially conserved. An examination of the published literature over the last 40 years reveals a great deal of conflicting data and interpretation. Using SAA's conserved amino acid sequence and the physiological effects it has while in its native structure, namely an HDL apolipoprotein, we argue that much of the confounding data and interpretation relates to experimental pitfalls not appreciated when working with SAA, a failure to appreciate the value of physiologic studies done in the 1970-1990 and a current major focus on putative roles of SAA in atherogenesis and chronic disease. When viewed from an evolutionary perspective, published data suggest that acute-phase SAA is part of a systemic response to injury to recycle and reuse cholesterol from destroyed and damaged cells. This is accomplished through SAA's targeted delivery of HDL to macrophages, and its suppression of ACAT, the enhancement of neutral cholesterol esterase and ABC transporters in macrophages. The recycling of cholesterol during serious injury, when dietary intake is restricted and there is an immediate and critical requirement of cholesterol in the generation of myriads of cells involved in inflammation and repair responses, is likely SAA's important survival role. Data implicating SAA in atherogenesis are not relevant to its evolutionary role. Furthermore, in apoE(-/-) mice, domains near the N- and C- termini of SAA inhibit the initiation and progression of aortic lipid lesions illustrating the conflicting nature of these two sets of data.

Adipokines and cardiovascular risk in Cushing's syndrome

Cushing's syndrome (CS) is associated with increased cardiovascular morbidity and mortality. Recent evidence also suggests that increased cardiovascular risk may persist even after long-term remission of CS. Increased central obesity, a typical feature of CS, is associated with altered production of adipokines, which contributes to the pathogenesis of several metabolic and cardiovascular complications observed in this condition. In vitro and in vivo studies have shown a relationship between cortisol and adipokines in several experimental settings. In patients with either active or 'cured' CS, an increase in leptin and resistin levels as well as the release of pro-inflammatory cytokines, such as tumor necrosis factor-α and interleukin-6, may be associated with increased cardiovascular risk. For other adipokines, including adiponectin, results are inconclusive. Studies are needed to further elucidate the interactions between clinical and subclinical increases in cortisol production and altered adipokine release in CS.

Multiple biomarkers at admission significantly improve the prediction of mortality in patients undergoing primary percutaneous coronary intervention for acute ST-segment elevation myocardial infarction

OBJECTIVES

We investigated whether multiple biomarkers improve prognostication in ST-segment elevation myocardial infarction (STEMI) patients undergoing primary percutaneous coronary intervention.

BACKGROUND

Few data exist on the prognostic value of combined biomarkers.

METHODS

We used data from 1,034 STEMI patients undergoing primary percutaneous coronary intervention in a high-volume percutaneous coronary intervention center in the Netherlands and investigated whether combining N-terminal pro-brain natriuretic peptide, glucose, C-reactive protein, estimated glomerular filtration rate, and cardiac troponin T improved the prediction of mortality. A risk score was developed based on the strongest predicting biomarkers in multivariate Cox regression. The additional prognostic value of the strongest predicting biomarkers to the established prognostic factors (age, body weight, diabetes, hypertension, systolic blood pressure, heart rate, anterior myocardial infarction, and time to treatment) was assessed in multivariable Cox regression.

RESULTS

During follow-up (median, 901 days), 120 of the 1,034 patients died. In Cox regression, glucose, estimated glomerular filtration rate, and N-terminal pro-brain natriuretic peptide were the strongest predictors for mortality (p < 0.05, for all). A risk score incorporating these biomarkers identified a high-risk STEMI subgroup with a significantly higher mortality when compared with an intermediate- or low-risk subgroup (p < 0.001). Addition of the 3 biomarkers to established prognostic factors significantly improved prediction for mortality, as shown by the net reclassification improvement (0.481, p < 0.001) [corrected] and integrated discrimination improvement (0.0226, p = 0.03) [corrected].

CONCLUSIONS

Our data suggest that addition of a multimarker to a model including established risk factors improves the prediction of mortality in STEMI patients undergoing primary percutaneous coronary intervention. Furthermore, the use of a simple risk score based on these biomarkers identifies a high-risk subgroup.

[Urgent percutaneous coronary intervention leads to a decrease in serum concentrations of soluble CD40 ligand]

BACKGROUND/AIM

Inflammation as a consequence of vascular injury after percutaneous coronary intervention (PCI) is a pathological substrate of restenosis and of its complications. The aim of the study was to examine perprocedural inflammatory response expressed by soluble CD40 ligand (sCD40L) and C-reactive protein (CRP) in patients treated with PCI and dual antiplatelet therapy.

METHODS

The experimental group included 52 patients (80.8% men, age 60 +/- 9 years) with angina pectoris treated by PCI (22 urgent PCI) with stent implantation, and dual antiplatelet therapy (tienopiridins and aspirin), according to the current recommendations for the execution of the intervention. The control group consisted of 8 patients (70.5% men, age 59 +/- 7 years) with angina pectoris, who had undergone coronarography taking aspirin 3 days prior to it. In all the patients 24 hours before and after the PCI concentrations of CRP and sCD40L in the blood were determined.

RESULTS

In the experimental group, the concentration of sCD40L was lower as compared to the control (p < 0.02). In 34 (65%) patients postprocedural decrease in sCD40L was recorded, in 18 (34.6%) of them increase, while in 50 (96%) patients there was a rise in CRP. The patients with postprocedural fall in sCD40L hod greater preprocedural concentration of sCD40L (p < 0.001), and less postprocedural concentration of sCD40L (p < 0.001), compared to the group with an increase in sCD40L after the PCI, while CRP levels between these groups were not statistically different. Patients treated with emergency PCI compared to elective patients had a postprocedural decrease in sCD40L (p = 0.02). Increase in the level of CRP was higher in the group with emergency PCI in relation to elective PCI (p < 0.01).

CONCLUSION

Emergency PCI procedures in the treatment of patients with unstable angina pectoris lead to a postprocedural fall in the serum concentration of sCD40L. Dual antiplate therapy with tienopiridins and aspirin inhibits the release of sCD40L. Regardless a clinical presentation of coronary disease PCI leads to an postprocedural increase in concentrations of CRP in the serum.

Coronary stenting is associated with an acute increase in plasma myeloperoxidase in stable angina patients but not in patients with acute myocardial infarction

BACKGROUND

Myeloperoxidase (MPO) has emerged as a critical mediator in the physiopathology of atherosclerosis from plaque formation and growth until destabilization and rupture leading to acute coronary syndrome (ACS). Using coronary stenting as a model of plaque injury, we aimed to determine the evolution of systemic MPO levels following coronary stenting in stable angina patients and in patients with acute myocardial infarction (AMI).

METHODS

Plasma levels of MPO, lactoferrin, interleukin (IL)-6, C-reactive protein and PMN counts were assessed in 13 patients with Non-ST-elevation myocardial infarction (NSTEMI) (Group A) and in 29 patients with stable angina pectoris (Group B), undergoing coronary stenting. Serial blood samples were taken before angioplasty (baseline) and at 1, 6 and 24 h following initial balloon inflation.

RESULTS

Following angioplasty, the overall plasma MPO levels significantly increased at 1 h in group B (120.5+/-79.0 to 166+/-79.5, p=0.003) but not in group A (121+/-63.4 to 124.7+/-76.9, p=0.753). In Group B, the increase in MPO levels at 1 h were significantly higher in the presence of complex lesions compared to patients with simple lesions (p=0.023). Lactoferrin levels showed no change over time except for a significant decrease at 6 h in group B.

CONCLUSIONS

In stable angina patients, coronary stenting is associated with an acute and transient increase in plasma MPO levels, but not in lactoferrin levels, with an enhanced response in the presence of complex lesions. In contrast, we observed no changes in plasma MPO and lactoferrin levels following stenting in patients with AMI. Given its pro-inflammatory properties, the potential implication of MPO release on clinical outcome in stable patients undergoing stenting needs further investigation.

Procalcitonin in acute myocardial infarction

OBJECTIVE

Procalcitonin (PCT) is released in severe bacterial infections, sepsis and in infection independent cases such as major surgery, multiple trauma, cardiogenic shock, burns, resuscitation, and after cardiac surgery. The aim of this study was to determine the levels and the kinetics of PCT in AMI and to investigate their possible correlation with the release of IL-6 and CRP. DESIGN-PATIENTS: The study included 60 patients (47 men, 63.2+/-14.8 years) with the diagnosis of AMI at admission. In all patients, serum levels of PCT, IL-6, CK-MB, TnI and CRP were measured at admission, at 3, 6, 12, 24, 48 and 72 h and at the seventh day.

RESULTS

PCT was elevated in all patients with AMI. It was initially detected in serum approximately 2-3 h after the onset of the symptoms. The median value at admission was 1.3 ng/ml (95% CI: 0.89 to 1.80). The value of PCT showed an increase and reached a plateau after 12-24 h. The median value at 24 h was 3.57 ng/ml (95% CI: 2.89 to 4.55). PCT values fell to baseline (<0.5 ng/ml) by the seventh day. PCT was detected in serum earlier than CK-MB or TnI in 56 of the 60 patients (93.3%). The kinetics of PCT was similar to those of CK-MB and TnI. The maximal values of PCT were positively correlated with the maximal values of IL-6 (r = 0.59, P = 0.00) and of CRP (r = 0.65, P = 0.001). The maximal values of IL-6 were positively correlated with max CRP (r = 0.35, P = 0.045).

CONCLUSIONS

PCT could be considered as a novel sensitive myocardial index. Its release in AMI is probably due to the inflammatory process that occurs during AMI.

Acute arterial thrombosis in the absence of inflammation: the stress-related anti-inflammatory hormone ACTH participates in platelet-mediated thrombosis

OBJECTIVE

Despite the reciprocal relationship that exists between inflammation and thrombosis, we asked whether thrombosis can develop without inflammation, and whether stress-related hormones (ACTH and cortisol) influence platelet-mediated thrombosis.

METHODS

We investigated the role of ACTH and cortisol in platelet aggregation, as well as on the circulating levels of IL-6 in pigs subjected to different treatments. In control animals, deep vessel wall injury (DVWI) was induced in the right common carotid artery, while in the animals under study DVWI was induced 60 min after ACTH administration (subgroup 1) or not at all (subgroup 2). In an ex vivo study we evaluated whether ACTH or cortisol modulates platelet aggregation. Indeed, we assessed whether blocking the P2Y platelet receptors inhibits the effect of ACTH on platelet aggregation. Finally, we assessed whether ACTH mobilizes intracellular calcium and modulates intracellular cAMP in platelets ex vivo.

RESULTS

We found that the suppression of inflammation following ACTH administration was accompanied by acute arterial thrombosis in the zone of injury in vivo. Furthermore, ACTH but not cortisol amplifies the platelet aggregation induced ex vivo by agonists. Platelets do not express ACTH receptors which may explain why ACTH does not reduce intracellular levels of cAMP in platelets. Nevertheless, supraphysiological concentrations of ACTH increase calcium mobilization in platelets.

CONCLUSION

These results indicate for the first time that ACTH may fulfil an important role in acute arterial thrombosis by increasing the platelet aggregation induced by agonists, probably via a G(q)-coupled pathway.

Higher body mass index (BMI) is associated with reduced glucocorticoid inhibition of inflammatory cytokine production following acute psychosocial stress in men

BACKGROUND

Body mass index (BMI) and mental stress seem to exert part of their cardiovascular risk by eliciting inflammation. However, the adverse effects of stress on inflammatory activity with BMI are not fully understood. We investigated whether higher BMI is associated with reduced glucocorticoid inhibition of inflammatory cytokine production following stress in men while controlling for age and blood pressure. We measured glucocorticoid inhibition of lipopolysaccharide (LPS)-stimulated release of the proinflammatory cytokine tumor necrosis factor (TNF)-alpha.

METHODS

Forty-two men (age range 21-65 years; BMI range 21-34 kg/m(2)) underwent the Trier Social Stress Test (combination of mock job interview and mental arithmetic task). Whole blood samples were taken immediately before and after stress, and during recovery up to 60 min post-stress. Glucocorticoid sensitivity of LPS-stimulated TNF-alpha expression was assessed in vitro with and without coincubating increasing doses of dexamethasone. Moreover, salivary cortisol was measured during the experiment and on a normal day for assessment of baseline circadian cortisol.

RESULTS

Higher BMI was associated with lower glucocorticoid sensitivity of monocyte TNF-alpha production after stress (main effect of BMI: p<0.001) and with more pronounced decreases of glucocorticoid sensitivity following stress (interaction of stress-by-BMI: p=0.002). Neither LPS-stimulated TNF-alpha release nor baseline glucocorticoid sensitivity were associated with BMI. Similarly, BMI was not associated with salivary cortisol, either in reaction to stress or in circadian cortisol secretion.

CONCLUSIONS

Our data suggest that with increasing BMI, glucocorticoids are less able to inhibit TNF-alpha production following stress. This might suggest a new mechanism linking BMI with elevated risk for adverse cardiovascular outcomes following stress.

C-reactive protein levels do not correlate with retinal artery occlusion but with atherosclerosis

PURPOSE

To determine C-reactive protein (CRP) levels in acute retinal artery occlusion (RAO) and their association with atherosclerotic risk factors.

METHODS

CRP levels in 16 patients with RAO were compared with levels in 16 age-matched controls at risk of atherosclerosis and 16 young volunteers. Repeated CRP testing was performed 6 years later.

RESULTS

Elevated CRP levels (>3 mg/l) and risk factors for atherosclerosis were detected in seven patients in the study group (44%) and nine at-risk controls (56%). On follow-up, CRP levels were reduced in all seven retested patients. Six patients died of vascular events within 5 years, of whom four had high CRP levels during RAO.

CONCLUSIONS

CRP level correlates with atherosclerosis but it is not significantly elevated in patients with RAO.

Effects of acute mental stress and exercise on inflammatory markers in patients with coronary artery disease and healthy controls

Physical and mental stressors result in increased inflammation markers in populations free of coronary artery disease (CAD). However, inflammatory responses to mental and exercise challenges have not been established in patients with CAD. This study investigated the responses of inflammatory markers, including C-reactive protein (CRP), interleukin-6 (IL-6), and soluble intercellular adhesion molecule-1, in patients with CAD after successful elective percutaneous coronary intervention (n = 36, 59 +/- 8 years of age, 33% women) and healthy controls without a history of CAD (n = 28, 54 +/- 10 years of age, 36% women). Increases in inflammatory markers were examined in response to mental challenge tasks (anger recall and mental arithmetic) and treadmill exercise. Stress echocardiography was used to rule out stress-induced ischemia as a possible confounding factor. Results showed that CRP increased significantly to mental challenge and exercise (p values <0.01), and CRP responses were higher in patients with CAD than in controls (change in mental arithmetic 0.19 +/- 0.11 vs 0.01 +/- 0.03 mg/L, p = 0.003; change in exercise 0.57 +/- 0.11 vs 0.08 +/- 0.0.03 mg/L, p = 0.001). Increased norepinephrine responses were related to larger CRP and IL-6 increases to mental challenge tasks (p values <0.05). Exercise elicited increased CRP, IL-6, and soluble intercellular adhesion molecule-1 levels (p values <0.01), and these responses were larger than with mental challenge tasks (p values <0.05). In conclusion, mental stress and exercise induce increased levels of inflammatory markers in patients with CAD. These stress-induced increases are larger than in healthy subjects, occur in the absence of myocardial ischemia, and are related to the neurohormonal stress response.

Effect of statin therapy before Q-wave myocardial infarction on myocardial perfusion

Recent studies emphasized the non-lipid-lowering effects of hydroxymethylglutaryl coenzyme A reductase inhibitors on endothelial function, inflammation, and platelet activation in patients with stable atherosclerosis. This study sought to evaluate the impact of statin pretreatment in patients with acute myocardial infarction (AMI) on level of systemic inflammation and myocardial perfusion. A total of 253 consecutive patients undergoing primary angioplasty on a native vessel within 12 hours of AMI were divided into a group with statin pretreatment (n = 86) and control patients (n = 167). Angiographic myocardial blush grade (MBG) after revascularization of the infarct-related artery was determined to evaluate myocardial perfusion. Statin pretreatment was associated with a lower frequency of increased C-reactive protein (>or=5 mg/L) on admission compared with the control group (48% vs 64%; p = 0.019). The frequency of normal perfusion (MBG 3) was higher in the statin-pretreatment group than the control group (45% vs 26%, respectively; p <0.001). Statin pretreatment was an independent predictor of normal myocardial perfusion (MBG 3; odds ratio 2.53, 95% confidence interval 1.15 to 9.53, p = 0.022) in addition to age <or=70 years and C-reactive protein <5 mg/L. In conclusion, statin pretreatment in patients with AMI was associated with decreased systemic inflammation and better perfusion after primary angioplasty of the infarct-related artery.

1059G/C polymorphism within the exon 2 of the C-reactive protein gene: relationship to C-reactive protein levels and prognosis in unstable angina

OBJECTIVE

Patients with unstable angina (UA) and high C-reactive protein (CRP) have increased cardiovascular risk. Whether genetic factors such as the synonymous 1059G/C polymorphism within the exon 2 of the human CRP gene determine CRP levels and outcome is unclear.

METHODS

In 105 consecutive patients with UA, we assessed the CRP 1059G/C polymorphism, CRP plasma levels and interleukin-6 production after in-vitro stimulation of whole blood with lipopolysaccharide (1 ng/ml). Coronary events during a 24-month follow-up were recorded.

RESULTS

CRP levels (median, range) were significantly lower among C-allele carriers (2.3 mg/l, 0.5-26.9) than among GG homozygotes (5.9 mg/l, 0.8-72.12, P=0.009). Interleukin-6 production was lower in C-allele carriers (1645 pg/ml, 832.0-9522) than in GG homozygotes (3929 pg/ml, 670.8-10 582), (P=0.085). At follow-up, 1059C-allele carriers experienced fewer coronary events than 1059GG homozygotes (13 vs. 47%, P=0.021). At multivariable analysis, a CRP level >3 mg/l, but not the 1059G/C polymorphism, was an independent predictor of coronary events (odds ratio 10.04, 95% confidence interval 2.84-35.44, P=0.0002).

CONCLUSION

This study shows that the CRP synonymous 1059G/C polymorphism affects CRP levels. No independent association was, however, observed between this polymorphism and clinical outcome in UA.

Role of pre-infarction angina and inflammatory status in the extent of microvascular obstruction detected by MRI in myocardial infarction patients treated by PCI

BACKGROUND/OBJECTIVES

The extent of microvascular obstruction (MVO) during myocardial infarction referred to as the "no-reflow phenomenon", may determine myocardial damage. Our study aimed to investigate the incidence and the influencing factors of MVO in patients with ST-elevation myocardial infarction (STEMI) treated by primary percutaneous intervention (PCI).

PATIENTS, METHODS

Using contrast-enhanced MRI, microvascular obstruction was defined as early hypoenhancement. Contrast defects were scored from 0 (no hypoenhancement) to 3 (strong hypoenhancement). 50 patients (56+/-11 years) with STEMI underwent PCI. Contrast-enhanced MRI (6+/-2 days after STEMI) and biochemical parameters were evaluated.

RESULTS

Microvascular obstruction (score 1 to 3) was observed in 90% of the patients and major microvascular obstruction (score 2-3) in 54%. In univariate analysis, leukocytes and CRP levels were associated with MVO, whereas pre-infarction angina and prior medication by aspirin or calcium channel antagonist appeared protective. Microvascular obstruction intensity positively correlated with baseline inflammation status assessed by C-reactive protein and leukocytes (rho=0.43 and rho=0.44; p=0.003), the peak of CK (rho=0.56; p=0.01) or Troponin I (rho=0.59; p=0.01) and negatively correlated with LVEF (rho=-0.44; p=0.002). Multivariate analysis identified the absence of pre-infarction angina as the only independent predictor for microvascular obstruction (odds ratio, 8.35, 95% confidence interval 1.27-54.71; p=0.027).

CONCLUSION

MRI-detected microvascular obstruction has a high incidence in patients with STEMI treated by primary PCI and determines post-MI LVEF even in patients with post PCI TIMI 3 flow score. Pre-infarction angina appears to be an independent determinant of the extent of MVO detected by MRI.

Beneficial effects of cardiac rehabilitation and exercise after percutaneous coronary intervention on hsCRP and inflammatory cytokines in CAD patients

Recent studies showed that tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6), as well as high-sensitive C-reactive protein (hsCRP) levels are predictive factors of cardiovascular risk. However, the effect of cardiac rehabilitation (CR) intervention in coronary artery disease (CAD) patients on these factors is not known. The aim of this study was to evaluate the effects of CR and exercise on hsCRP and inflammatory cytokine levels in patients with CAD after percutaneous coronary intervention (PCI). CAD patients who underwent PCI were divided into a CR and exercise group (CRE, n = 29) or a control group (CON, n = 10). CR and exercise consisted of 6 weeks supervised exercise training and 8 weeks home-based, self-managed exercise. Compared to pre-experimental levels, TNF-alpha (by 20.4%; p = 0.006) and IL-6 (by 49.0%; p < 0.0001), as well as hsCRP (by 59.4%; p < 0.0001), were markedly decreased after CR and exercise in CAD patients but not in control group, except for IL-6 (by 41.6%; p = 0.001). However, there was no significant alteration of adiposity-related variables such as BMI, percent body fat, and waist circumferences, in both groups. We suggest that CR and exercise in CAD patients after PCI induce significant reduction in hsCRP and inflammatory cytokines (TNF-alpha and IL-6), and marked increase in exercise tolerance and capacity.

Unusual CD4+CD28null T lymphocytes and recurrence of acute coronary events

OBJECTIVES

We hypothesized that the expansion of unusual T lymphocytes, CD4+CD28null T cells, might represent a key pathogenetic mechanism of recurrent instability.

BACKGROUND

Clinical presentation of acute coronary syndromes (ACS) is variable. Some patients have recurrent episodes of instability, despite optimal treatment, whereas others have a single acute event in their life. The CD4+CD28null T cells, with a functional profile that favors vascular injury, have recently been found both in peripheral blood and in unstable coronary plaques of patients with ACS.

METHODS

Peripheral blood T cells from 120 consecutive unstable angina (UA) patients were analyzed for the distribution of T-cell subsets by flow cytometry. Patients were subgrouped according to the occurrence of prior (during the 24 months before the study enrollment) and subsequent (during the 24 months of follow-up) acute coronary events. For 51 patients, the index event was the first ever (G1); 30 patients had prior events (G2); and 39 patients had further events at follow-up (death, myocardial infarction, or UA) or both before and after the index event (G3).

RESULTS

The CD4+CD28null T-cell frequency was higher in G3 than in G2 and G1 (median 9.5% [range 2.4% to 48.0%] vs. 5.1% [range 0.4% to 27.8%] and 2.3% [range 0.2% to 22.8%], respectively; p < 0.001). The expansion of these unusual T lymphocytes was higher in patients with elevated C-reactive protein levels, and it was reduced by statin therapy. On multivariate logistic regression analysis, CD4+CD28null T-cell frequency was an independent predictor of future acute coronary events (odds ratio 3.01, 95% confidence interval 1.1 to 8.25; p = 0.023).

CONCLUSIONS

A perturbation of T-cell repertoire is strongly associated with the recurrence of acute coronary events, conceivably playing a key pathogenetic role.

Chemokines and left ventricular function in patients with acute myocardial infarction

BACKGROUND

Leukocytes are activated in the inflammatory process involving locally atherosclerotic lesions through adhesive molecules attaching to the surface of endothelial cells, especially during acute myocardial infarction. The aim of the study was to assess MCP-1, MIP-1alpha, and RANTES serum levels in patients with STEMI and to correlate them with the severity of left ventricle (LV) dysfunction.

METHODS

Forty patients were initially divided into two groups, with group 1 having an ejection fraction (EF) above 40% and group 2 an EF of 40% or less. Next, the patients were divided on the basis of wall motion score index (WMSI): group 3 had a WMSI of 1.3 or lower and group 4 had a WMSI above 1.3. A control group of ten volunteers was also included in the study. Serum samples were taken at admission as well as 3, 24, 48, 72 h, and 7 days after.

RESULTS

The baseline serum levels of MCP-1 and RANTES in group 1 were significantly higher than in the controls (p<0.05 and p<0.005, respectively). The highest concentrations of chemokines were observed 3 h after admission. The serum levels of MIP-1alpha on admission and 3 h later were significantly higher in group 1 than in group 2 (p<0.03 and p<0.01, respectively). Maximum MIP-1 concentrations were observed 3 h after admission in group 3 and 24 h after admission in group 4 (p<0.006). In group 1, MIP-1alpha 3 h after admission correlated positively with the EF (r=0.444, p<0.05). In group 1 there was a negative correlation between MIP-1alpha concentration 3 h after admission and LV end-diastolic dimension (r=-0.492, p<0.02).

CONCLUSIONS

Patients with myocardial infarction with an elevated ST segment had a significant increase in MCP-1, MIP-1alpha, and RANTES serum levels.

Persistent activation of nuclear factor kappa-B signaling pathway in patients with unstable angina and elevated levels of C-reactive protein evidence for a direct proinflammatory effect of azide and lipopolysaccharide-free C-reactive protein on human monocytes via nuclear factor kappa-B activation

OBJECTIVES

Our study investigated: 1) the contribution of nuclear factor kappa-B (NF-kappaB) signaling pathway to the enhanced inflammatory response observed in unstable angina (UA) patients with elevated levels of C-reactive protein (CRP); and 2) whether CRP may have direct proinflammatory effects via NF-kappaB activation.

BACKGROUND

Unstable angina patients with elevated CRP have enhanced inflammatory response and increased risk of persistent instability, myocardial infarction, and death.

METHODS

We studied 28 patients with history of UA and persistently elevated CRP (>3 mg/l) followed for 24 months and free of symptoms for at least 6 months (group 1), 14 patients with history of UA and low CRP (group 2), and 24 patients with chronic stable angina and low CRP (group 3). Peripheral blood monocytes were analyzed for spontaneous NF-kappaB activation and interleukin (IL)-6 and tumor necrosis factor (TNF)-alpha production. To assess the direct proinflammatory effects of CRP, monocytes from 8 healthy subjects were stimulated in vitro with increasing doses of CRP (5 to 10 to 25 microg/ml), lipopolysaccharide (LPS) (1 to 10 ng/ml), or both.

RESULTS

Spontaneous NF-kappaB activation in vivo was demonstrated in 82% of group 1 versus 14% of group 2 and 21% of group 3 patients (p < 0.001). Interleukin-6 and TNF-alpha production was significantly correlated with the NF-kappaB activation status (r = 0.55, p < 0.001 and r = 0.53, p = 0.006, respectively). Patients with NF-kappaB activation had recurrence of acute coronary events (60% vs. 28%; p = 0.017). C-reactive protein induced a significant but modest in vitro NF-kappaB activation in human monocytes (p = 0.002). Coincubation with LPS produced a greater-than-additive response (p < 0.01 vs. CRP and LPS alone).

CONCLUSIONS

Nuclear factor kappa-B activation might represent a mechanism by which CRP amplifies and perpetuates the inflammatory component of acute coronary syndromes and influences the clinical outcome.

Plasma C-reactive protein predicts left ventricular remodeling and function after a first acute anterior wall myocardial infarction treated with coronary angioplasty: comparison with brain natriuretic peptide

BACKGROUND

C-reactive protein (CRP) directly participates in the myocardial injury of acute myocardial infarction (MI). Although high plasma CRP levels in the acute phase strongly indicate a poor early clinical outcome of patients with MI, the impact of CRP levels on late left ventricular (LV) function and remodeling, which are closely associated with long-term prognosis, remains unknown.

HYPOTHESIS

Acute plasma CRP levels may predict late LV function and remodeling after MI.

METHODS

We prospectively studied 12 consecutive patients with a first acute anterior MI recanalized by angioplasty. We measured plasma CRP levels on Days 0, 1, 2, 3, 4, and 7, and calculated the area under the curve (AUC). We also measured plasma brain natriuretic peptide (BNP) levels on Day 3 as the referential indicator of LV dysfunction and late LV remodeling. Late LV indices were independently assessed on a left ventriculogram obtained at 5.3 months to estimate the extent of LV remodeling.

RESULTS

Plasma CRP reached its peak at Day 2.8 (8.68+/-4.57 mg/dl). On linear regression analysis, the AUC of CRP (35.21+/-19.33 mg/dl x day) correlated positively with BNP (316.5+/-418.6 pg/ml) (r = 0.646, p = 0.023). The AUC of CRP, peak CRP, and BNP correlated significantly with late LV indices. Among these, the AUC of CRP showed the best correlation with end-diastolic volume index (r = 0.765, p = 0.004), end-systolic volume index (r = 0.907, p < 0.001), and ejection fraction (r = -0.862, p < 0.001).

CONCLUSIONS

Patients with high plasma CRP levels may be at risk for late LV dysfunction and remodeling; theoretically, their long-term prognosis may be poor. Measuring plasma CRP levels may provide valuable information for long-term risk stratification after MI.

Soluble CD40 ligand and interleukin-6 in the coronary circulation after acute myocardial infarction

BACKGROUND

Inflammation, operated by blood, vascular and immune cells interaction, is implicated in plaque disruption and CD40 ligand (CD40L) was identified on activated T cells and platelets. We sought to investigate the roles of local inflammation in acute myocardial infarction (AMI).

METHODS

Coronary sinus (CS) and arterial (A) levels of interleukin (IL)-6 and soluble CD40L (sCD40L) and matrix metalloproteinase (MMP)-9 activity in serial blood samples obtained until 48 h after percutaneous coronary intervention (PCI) were determined. In tissue specimens obtained by aspirating thrombectomy and directional coronary atherectomy, CD40L was immunohistochemically stained.

RESULTS

Trans-cardiac gradient (CS-A) of IL-6, indicating cardiac release into the coronary circulation, significantly increased at 24 h after PCI in patients with AMI (group MI, n=17) in contrast with angina pectoris (n=10). Soluble CD40L levels in CS showed earlier peak, yielding trans-cardiac gradient, at 9 h in both groups. The maximum (max) release of IL-6 in MI, but not sCD40L, positively correlated with end-diastolic volume index (R=0.84) and negatively with ejection fraction (R=-0.66) by contrast ventriculography at 6-month follow up. Immunohistological study revealed the expression of CD40L in intra-coronary occlusive and mural thrombi. Aspirating thrombectomy significantly reduced the increase in both sCD40L levels and MMP-9 activity, but not max IL-6 release in MI.

CONCLUSIONS

In contrast with myocardial injury represented by IL-6 release, acute rise in sCD40L levels with the MMP-9 activation in the coronary circulation may possibly reflect local inflammation with platelet activation and be a novel marker of plaque damage by PCI.

Pathogenesis and early management of non-ST-segment elevation acute coronary syndromes

NSTE ACS is a clinically significant problem. Endothelial dysfunction triggered by traditional cardiovascular risk factors (and perhaps by other as yet unidentified risks) in the susceptible host leads to the formation and development of atherosclerotic plaque. Inflammatory mediators and mechanical stresses contribute to plaque rupture by disrupting the protective fibrous cap. In about 25% of patients who have ACS, typically those who are younger, female, or smokers, plaque erosion seems to be the main underlying pathologic mechanism. Endothelial alteration, inflammation,or exposure of the lipid core results in the release of TF, vWF, and PAF. The release of these factors leads to platelet activation and aggregation as well as to the formation of a fibrin clot, resulting in arterial thrombosis that occludes the vessel. A variety of factors, including circulating catecholamines, LDL levels, blood glucose levels, and systemic thrombogenic factors, can affect the extent and stability of the thrombus, thereby determining whether the occlusion is complete and fixed, labile and nonocclusive (NSTE ACS),or clinically silent resulting in a mural thrombus and plaque growth. The acute treatment of NSTEACS is directed at interrupting the prothrombotic environment surrounding the ruptured plaque; thus, antiplatelet agents such as aspirin, clopidogrel, and glycoprotein IIb/IIla receptor antagonists,as well as anticoagulants such as heparin, are the mainstays of early therapy.

Mechanisms of dysregulation of low-density lipoprotein receptor expression in vascular smooth muscle cells by inflammatory cytokines

OBJECTIVE

Although inflammation is a recognized feature of atherosclerosis, the impact of inflammation on cellular cholesterol homeostasis is unclear. This study focuses on the molecular mechanisms by which inflammatory cytokines disrupt low-density lipoprotein (LDL) receptor regulation.

METHODS AND RESULTS

IL-1beta enhanced transformation of vascular smooth muscle cells into foam cells by increasing uptake of unmodified LDL via LDL receptors and by enhancing cholesterol esterification as demonstrated by Oil Red O staining and direct assay of intracellular cholesterol concentrations. In the absence of IL-1beta, a high concentration of LDL decreased LDL receptor promoter activity, mRNA synthesis and protein expression. However, IL-1beta enhanced LDL receptor expression, overriding the suppression usually induced by a high concentration of LDL and inappropriately increasing LDL uptake. Exposure to IL-1beta also caused overexpression of the sterol regulatory element binding protein (SREBP) cleavage-activating protein (SCAP), and enhanced its translocation from the endoplasmic reticulum to the Golgi, where it is known to cleave SREBP, thereby enhancing LDL receptor gene expression.

CONCLUSIONS

These observations demonstrate that IL-1beta disrupts cholesterol-mediated LDL receptor feedback regulation, permitting intracellular accumulation of unmodified LDL and causing foam cell formation. The implication of these findings is that inflammatory cytokines may contribute to intracellular LDL accumulation without previous modification of the lipoprotein.

Predictive Value of C-Reactive Protein and Left Ventricular Diastolic Filling Pattern after a Non-ST Elevation Myocardial Infarction

BACKGROUND

Recent studies have shown that the odds ratio for high-sensitivity C-reactive protein (CRP) in predicting a coronary events in healthy subjects is 1.4, a value substantially less than previously reported. It is unclear whether this extends to acute coronary syndrome patients or if CRP would predict long-term events in this population. We evaluated the predictive value of CRP in patients with non-ST segment elevation myocardial infarction (NSTEMI) as their first manifestation of coronary artery disease and compared it with that of left ventricle diastolic function.

METHODS

Serum CRP concentration measurement and left ventricle diastolic function evaluation were performed in 51 consecutive patients with NSTEMI 48 hours, 3 months, and 6 months after infarction. Patients were followed for 1 year and events comprising the endpoints of death, new myocardial infarction, percutaneous coronary intervention, and coronary artery bypass grafting were reported.

RESULTS

Thirty of 51 patients developed the endpoints. Mean CRP concentration in patients who developed any endpoint and those who did not was similar at 48 hours, 3 months, and 6 months. A strong correlation between the presence of impaired relaxation 6 months after the infarction and development of the combined endpoints was noted (P < 0.001).

CONCLUSION

CRP has limited value in predicting future cardiovascular events in subjects with NSTEMI. Other biomarkers or a combination of other biomarkers may be needed to identify patients at high risk. Evaluation of diastolic left ventricular function not during the acute phase but 6 months later could predict adverse outcome in our series.

C-reactive protein increase in unstable coronary disease cause or effect?

A crucial point in understanding the clinical and pathophysiologic meaning of C-reactive protein (CRP) elevation in acute coronary syndromes (ACS) is whether CRP release is predominantly a response to even small amounts of myocardial necrosis, for which troponin is a sensitive and specific marker, or is an independent indicator of the inflammatory process occurring in that clinical condition. Whereas troponin is a good predictor of both mortality and myocardial infarction (MI), although the highest values are associated with a decreased probability of MI, CRP predicts mortality but has no relation with the early or late occurrence of MI. The large variability of CRP values in ACS may depend on the different response of this inflammation marker to various stimuli, some patients being particularly hyperresponsive, especially those with elevated CRP values at baseline. We hypothesize that myonecrosis, as detected by troponin increases, would represent the strongest stimulus for CRP increase in ACS, causing in some patients, especially those with already-elevated CRP values at baseline, a disproportionate increase of this marker. Accordingly, the highest CRP values during ACS are likely to be observed in patients with already-elevated CRP values at baseline (which would increase the probability of having death and MI in the follow-up) and the highest troponin values (which would increase the probability of death in the follow-up, but not of subsequent MI). This hypothesis would explain why high CRP levels in unstable coronary disease are good predictors of death, but not of MI.

Proinflammatory cytokines and myocardial viability in patients after acute myocardial infarction

BACKGROUND

Proinflammatory cytokines such as tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) can potentiate heart muscle damage during acute myocardial infarction (AMI). Whether changes in their plasma levels after AMI are dependent on the presence of myocardial viability is unclear. The aim of the study was to estimate the relation of time course of plasma TNF-alpha and IL-6 and the presence of reversible and irreversible myocardial dysfunction in patients early after AMI treated thrombolytically.

MATERIAL AND METHODS

Patients (54; mean age 60.4 +/- 11.7 years) with AMI plasma TNF-alpha and IL-6 were evaluated on the 2nd, 10th and 30th day after thrombolysis. Based on the response of dysfunctional segments of myocardium during dobutamine stress echocardiography performed on the 10th day, patients were divided into four groups: A, sustained improvement in contractility; B, biphasic (improvement followed by worsening); C, only worsening; D, no change. Twenty-two healthy persons served as controls.

RESULTS

On the 2nd day, all four groups of patients demonstrated increased levels of TNF-alpha and IL-6 and did not differ among one another regarding both cytokines. On the 10th day, plasma TNF-alpha and IL-6 decreased in each group and were the lowest in group A, intermediate in group B and the highest in groups C and D. On the 30th day, both cytokines were not different among all studied groups.

CONCLUSION

Elevated plasma TNF-alpha and IL-6 early after AMI decreased more quickly in patients with dysfunctional myocardium comprising not only necrotic but also viable segments. This decline is attenuated by the presence of residual ischemia.

Relationship between C-Reactive Protein and the Electrocardiographic Pattern on Admission in Patients with Acute Coronary Syndrome

BACKGROUND

In patients with acute coronary syndrome (ACS), the prevalence of a primary inflammatory pathogenic component of coronary instability, as detectable by elevated C-reactive protein (CRP), varies considerably. The aim of the present study was to assess the prevalence of inflammation in patients with ACS according to the different electrocardiographic (ECG) patterns on admission.

METHODS

Hundred and thirty-six consecutive patients with the diagnosis of acute myocardial infarction were divided in three groups according to the ECG pattern on admission. Group 1 included 59 patients with ST segment elevation, group 2 included 50 patients with ST depression and/or T wave inversion and group 3 included 27 patients with no ECG changes. CRP was measured on admission in all patients. For the prevalence of inflammation analysis, we used a cutoff value of 3 mg/l.

RESULTS

CRP was above cutpoint significantly more often in patients with ST depression and/or T wave inversion (44.1% in group 1, 70% in group 2 and 40.7% in group 3; p=0.009). Patients with similar ECG pattern and CRP levels above the cutpoint presented a poorer outcome (coronary death, myocardial infarction and recurrence of instability) at one-year follow-up: 54 versus 27% for group 1, 74 versus 27% for group 2 and 45 versus 31% for group 3.

CONCLUSIONS

Patients with ST depression and/or T wave inversion on admission exhibit a higher prevalence of elevated CRP than those with ST elevation or no ECG changes, suggesting an important heterogeneity of the role of inflammatory triggers of the clinical syndromes of coronary instability.

Endothelial microparticles correlate with high-risk angiographic lesions in acute coronary syndromes

BACKGROUND

Endothelial Microparticles (EMP) are small fragments of endothelial cell membrane shed during apoptosis or activation. Our group has previously reported elevations of EMP in patients with coronary artery disease (CAD), thrombotic thrombocytopenic purpura (TTP), pre-eclampsia, multiple sclerosis (MS), and severe hypertension (HTN). In the present study, we evaluate the possible relationship between EMP levels and the angiographic severity and characteristics of coronary obstructive lesions.

METHODS

We studied a total of 43 patients undergoing coronary angiography. Fifteen had presented with acute myocardial infarction (MI), 20 with unstable anginas (UA), 5 with stable angina (SA) and 3 with congestive heart failure. Coronary angiography was reviewed and coronary lesions were classified using the Ambrose classification. Coronary stenoses were classified as high and low risk. High-risk included lesions with eccentric appearance (type II), presence of thrombi, or multiple irregularities. Low-risk lesions were defined as concentric or type I. Lesions were also analyzed by degree of stenosis and history of acute coronary syndrome (ACS). EMP in plasma was assayed by flow cytometry.

RESULTS

EMP in eccentric type II or multiple irregular lesions (high-risk) were 2.5-fold higher than in type I or concentric (low-risk) lesions, p<0.05. Lesions with thrombi had three-fold higher EMP than those without (p=0.05). Mild stenosis (>20%-<45%) had three-fold higher EMP than more severe (>45%), and five-fold higher than those without stenosis (p<0.01). Among patients with type II lesions, those with first ACS episode had four-fold higher EMP levels than those with recurrent ACS (p<0.01).

CONCLUSION

High EMP was associated with high-risk angiographic lesions including eccentric type II, multiple irregular, and lesions with thrombi. Mild to moderate stenosis was associated with higher EMP levels than severe stenosis. EMP may be a useful marker in detecting endothelial injury and risk of ACS as defined by angiography.

Enhanced T-helper-1 lymphocyte activation patterns in acute coronary syndromes

OBJECTIVES

We sought to determine whether different stages of coronary artery disease (CAD) are associated with distinct differentiation patterns of activated T cells.

BACKGROUND

Atherosclerosis is an inflammatory disease. However, little is known about specific inflammatory cell activation in atherosclerosis, for example, the T-helper (Th)1/Th2-balance.

METHODS

We studied 18 patients with stable angina (SA), 28 patients with acute coronary syndrome (ACS) (16 with unstable angina pectoris and 12 with ST-segment elevation myocardial infarction), 19 patients with unheralded myocardial infarction (UH), and 16 control patients. Cytokine patterns and transcription factor signaling pathways of circulating T cells were characterized using reverse transcription polymerase chain reaction and flow cytometry.

RESULTS

Although interferon (IFN)-gamma(+)/CD3(+) T cells were approximately 2-fold greater in patients with SA or UH than in control subjects, there was a massive expansion of Th1 cells in patients with ACS (p < 0.001). This increase was paralleled by significantly increased mRNA transcript levels for signal-transducer-and-activator-4 (ACS 1.17 +/- 0.14 relative units [RU]; control patients 0.44 +/- 0.09 RU; SA 0.67 +/- 0.12 RU; UH 0.61 +/- 0.17 RU), interleukin-2 (ACS 1.55 +/- 0.51 RU; control patients 0.21 +/- 0.09 RU; SA 0.54 +/- 0.18 RU; UH 0.45 +/- 0.16 RU), and IFN-gamma in ACS (1.27 +/- 0.39 RU; control patients 0.35 +/- 0.09 RU; SA 0.58 +/- 0.11 RU; UH 0.53 +/- 0.24 RU; p < 0.002). Th2 and Th0 cells were not different across patient subsets. The burden of CAD was identical between SA (1.4 +/- 0.2 diseased vessels, 68 +/- 13% diameter stenosis) and ACS (1.4 +/- 0.2 diseased vessels, 64 +/- 17% diameter stenosis) but significantly greater in patients with UH (2.5 +/- 0.5 diseased vessels, 95 +/- 7% diameter stenosis; p < 0.05).

CONCLUSIONS

Patients with UH have a greater burden of obstructive CAD than SA but no greater T-cell activation. Patients with ACS have the same extent of CAD than SA but significantly greater activation of Th1 cells that may contribute to the increasing instability. Differences in circulating Th1 cells might indicate different pathogenic components, leading to ACS and UH.

Body Temperature – A Marker of Infarct Size in the Era of Early Reperfusion

We measured body temperature in 40 consecutive patients treated for a first ST elevation acute myocardial infarction (AMI) with primary percutaneous coronary interventions. Left ventricular function was assessed by echocardiography, and blood samples were drawn for highly sensitive C-reactive protein (hs-CRP), white blood cell (WBC) count, fibrinogen, creatine kinase (CK), and cardiac troponin I levels (cTnI). The median (25th, 75th quartiles) peak 24-hour temperature was 37.4 degrees C (36.9 degrees C, 37.6 degrees C). Variables significantly associated with peak 24-hour temperature were CK (p = 0.01, r = 0.42), wall motion index (p = 0.01, r = 0.41), hs-CRP (p = 0.01, r = 0.41), and cTnI (p = 0.03, r = 0.35). There was no significant correlation between peak 24-hour temperature and WBC count (p = 0.39, r = 0.14) and fibrinogen (p = 0.12, r = 0.21). Thus, peak 24-hour body temperature after ST elevation AMI probably reflects infarct size rather than a nonspecific inflammatory response.