Plasma levels of interleukin 2, 6, 10 and phenotypic characterization of circulating T lymphocytes in ischemic heart disease

Variations in the Gene Expression Profile in Atherosclerotic Patients with Non-Fatal ACS. A Preliminary Study

The pathophysiology of atherosclerosis and acute coronary syndrome (ACS) is related to interactions between immune cells, endothelium, and blood platelets. An increasing number of reports confirm the link between excessive immune activation and cellular cross-talk with ACS incidence. Our genetic and proteomic analysis was performed on strictly selected atherosclerotic patients with non-fatal ACS without typical risk factors and healthy donors. Results showed changes in the gene expression levels of the various inflammatory factors derived from the peripheral blood cells that drive the over-activation of the immune system. The enhanced activation of the immune system may lead to the overexpression of the pro-inflammatory mediators, which causes self-perpetuating machinery of processes associated with thrombosis. In our preliminary study, we confirmed an altered expression of genes associated with the inflammation and overall interaction of the vascular microenvironment. Furthermore, 5 of 92 analyzed genes, CCL2, CCR2, CSF2, GZMB, and ICOS, were expressed only in patients with ACS. In conclusion, the augmented expression of the pro-inflammatory genes from the peripheral blood cells may be a crucial genetic factor leading to the occurrence of acute inflammation and thus be significant in ACS pathogenesis.

Níveis de Interleucina-35 em Pacientes com Doença Arterial Coronariana Estável

Fundamento

Foi demonstrado que as subunidades de interleucina-35 (IL-35) estão fortemente expressas nas placas ateroscleróticas em humanos. Assim, considera-se que elas têm um papel na aterosclerose.

Objetivos

Neste estudo, os níveis de IL-35 foram comparados com o grupo controle em pacientes com doença arterial coronariana (DAC) estável, e a associação entre os níveis de IL-35 e o tipo, gravidade e extensão da lesão foram investigadas com o escore Gensini (GS) e o escore Syntax (SS) no grupo de pacientes

Métodos

Sessenta pacientes (18 mulheres e 42 homens) com DAC, diagnosticados por meio da angiografia coronária, que apresentaram dor no peito típica e teste de esforço não invasivo positivo, e 46 pacientes (18 mulheres e 28 homens) com luminograma normal, foram incluídos no estudo. Tanto o GS quanto o SS foram calculados para o grupo de pacientes, e esses valores foram comparados com os níveis de IL-35. Variáveis com distribuição não normal foram avaliadas com o teste U de Mann-Whitney, enquanto os parâmetros com distribuição normal foram analisados com o teste t de Student. A diferença entre as variáveis categóricas foi avaliada pelo teste de qui-quadrado ou de Fisher. Os valores de p<0,05 foram considerados como estatisticamente sinificativos.

Resultados

Não foram observadas diferenças significativas entre pacientes e o grupo controle em termos de características demográficas e achados laboratoriais. Em comparação ao grupo controle, os níveis de IL-35 no grupo com DAC foram consideravalmente menores (36,9±63,9 ng/ml vs. 33,2±13,2 ng/ml, p<0,008). Embora não tenha sido estatisticamente significativo, os níveis de IL-35 foram maiores em pacientes com SS mais baixo do que nos com SS mais alto (33,2±13,7 vs. 31,8±8,9, p=0,51). Os valores de IL-35 em pacientes com GS alto foram significativamente mais baixos do que em pacientes com GS baixo (35±17,4 vs. 30,7±8,6, p=0,043).

Conclusão

Demonstrou-se que os níveis de IL-35 podem ser um novo biomarcador para a DAC estável, e que a IL-35 está associada à extensão da DAC.

New Tool for Rapid and Accurate Detection of Interleukin-2 and Soluble Interleukin-2 Receptor α in Cancer Diagnosis Using a Bioresponsive Microgel and Multivalent Protein Binding

Interleukin-2 (IL-2) and its α receptor in soluble form (sIL-2Rα) are considered biomarkers for cancers and immune-related diseases. Enzyme-linked immunosorbent assay is the most common method used to evaluate biomarkers in clinical practice; it is precise but time-consuming and involves complicated procedures. Here, we have developed a rapid yet accurate modality for cancer diagnosis that enables on-site evaluation of cancer markers, that is, IL-2 and sIL-2Rα, without complicated pretreatment of cancer patient-derived blood samples. Surface plasmon resonance and bioresponsive microgels conjugated with IL-2 receptors, that is, IL-2Rβ and IL-2Rγ, were utilized to measure IL-2 and sIL-2Rα levels via multivalent protein binding (MPB) between the ligands and their receptors. Our results showed that this novel method enables us to perform cancer diagnosis with a 1000-fold dilution of serum in 10 min. The advantage of MPB-based cancer diagnosis originates from its great selectivity for a target molecule and tolerance to a myriad of nonspecific substances in serum, which allows on-site clinical evaluation. Importantly, our finding implies that MPB-based cancer diagnosis provides a new paradigm not only for improving cancer treatment but also for evaluating a target molecule in unpurified and complex solutions such as blood.

Influence of low-opioid anesthesia in cardiac surgery on dynamics of pro-inflammatory interleukin-6

Introduction

With coronary artery bypass grafting, patients are subjected to additional risk caused by both surgical treatment itself and pathophysiological changes in homeostasis, provoked by the action of anesthetics and cardiopulmonary bypass.

Material and methods

The study involved 60 patients, who had been subjected to coronary artery bypass grafting with cardiopulmonary bypass. All patients were divided into two groups: group I (30 patients) – low-opioid scheme of anesthesia and group II (30 patients) – standard scheme of anesthetic management. Blood interleukin-6 (IL-6) was identified before and after cardiopulmonary bypass using an ELISA test.

Results

Having compared IL-6 values between study groups after completion of cardiopulmonary bypass, it was established that IL-6 levels were 27.51% (p = 0.001) lower in patients of group I compared with the results of patients in group II. Patients in the first group had a significantly shorter time of mechanical ventilation compared to group II (2.1 ±0.7 hours vs. 3.9 ±0.9 hours, p = 0.021). Low cardiac output syndrome was significantly less frequently reported in patients of group I (10.0% vs. 33.3%, p = 0.028). In addition, patients in group I had a significantly shorter time of intensive care unit (ICU) stay (2.5 ±0.7 days vs. 3.5 ±1.0 days, p = 0.044).

Conclusions

Application of multimodal low-opioid anesthesia was associated with significantly lower IL-6 at the end of surgery, shorter mechanical ventilation duration, less frequent low cardiac output syndrome and need for catecholamines, and shorter ICU stays.

Role of cytokines and inflammation in heart function during health and disease

By virtue of their actions on NF-κB, an inflammatory nuclear transcription factor, various cytokines have been documented to play important regulatory roles in determining cardiac function under both physiological and pathophysiological conditions. Several cytokines including TNF-α, TGF-β, and different interleukins such as IL-1 IL-4, IL-6, IL-8, and IL-18 are involved in the development of various inflammatory cardiac pathologies, namely ischemic heart disease, myocardial infarction, heart failure, and cardiomyopathies. In ischemia-related pathologies, most of the cytokines are released into the circulation and serve as biological markers of inflammation. Furthermore, there is an evidence of their direct role in the pathogenesis of ischemic injury, suggesting cytokines as potential targets for the development of some anti-ischemic therapies. On the other hand, certain cytokines such as IL-2, IL-4, IL-6, IL-8, and IL-10 are involved in the post-ischemic tissue repair and thus are considered to exert beneficial effects on cardiac function. Conflicting reports regarding the role of some cytokines in inducing cardiac dysfunction in heart failure and different types of cardiomyopathies seem to be due to differences in the nature, duration, and degree of heart disease as well as the concentrations of some cytokines in the circulation. In spite of extensive research work in this field of investigation, no satisfactory anti-cytokine therapy for improving cardiac function in any type of heart disease is available in the literature.

Impact of Low-Dose Occupational Exposure to Ionizing Radiation on T-Cell Populations and Subpopulations and Humoral Factors Included in the Immune Response

The aim of the present study is to assess the effects of low-dose occupational exposure on T helper response. One Hundred five employees working in Nuclear Power Plant, Kozloduy, Bulgaria and control group of 32 persons are included in this investigation. Flow cytometry measurements of T-cell populations and subpopulations and natural killer T cells are performed and levels of G, A, and M immunoglobulins and interleukin 2 (IL-2), IL-4, and interferon γ were determined. The data interpreted with regard to cumulative doses, length of service, and age. The results of the present study are not enough to outline a clear impact of occupational radiation exposure on T helper populations. Nevertheless, the observed even slight trends in some lymphocyte’s populations and in cytokines profile give us the reason to assume a possibility of a gradual polarization of T helper 1 to T helper 2 immune response at dose range 100 to 200 mSv. The results of the present study indicate the need to perform a more detailed epidemiological survey including potential confounding and misclassifying factors and possible selection bias that could influence the results.

The influence of low-grade inflammation on platelets in patients with stable coronary artery disease

Inflammation is likely to be involved in all stages of atherosclerosis. Numerous inflammatory biomarkers are currently being studied, and even subtle increases in inflammatory biomarkers have been associated with increased risk of cardiovascular events in patients with coronary artery disease (CAD). Low-grade inflammation may influence both platelet production and platelet activation potentially leading to enhanced platelet aggregation. Thrombopoietin is considered the primary regulator of platelet production, but it likely acts in conjunction with numerous cytokines, of which many have altered levels in CAD. Previous studies have shown that high-sensitive C-reactive protein (CRP) independently predicts increased platelet aggregation in stable CAD patients. Increased levels of CRP, fibrinogen, interleukin-6, stromal cell-derived factor-1, CXC motif ligand 16, macrophage migration inhibitory factor, RANTES, calprotectin, and copeptin have been associated with increased risk of cardiovascular events in CAD patients. Additionally, some of these inflammatory markers have been associated with enhanced platelet activation and aggregation. However, CRP and other inflammatory markers provide only limited additional predictive value to classical risk factors such as smoking, blood pressure, and cholesterol levels. Existing data do not clarify whether inflammation simply accompanies CAD and increased production and aggregation of platelets, or whether a causal relationship exists. In this review, we provide a comprehensive overview of inflammatory markers in stable CAD with particular emphasis on platelet production, activation, and aggregation in CAD patients.

Effects of trimetazidine on interleukin-2 and interleukin-8 concentrations in patients with coronary artery disease

Trimetazidine (TMZ) exhibits metabolic and cardioprotective effects. The aim of this study was to assess the effects of TMZ on interleukin-2 (IL-2) and interleukin-8 (IL-8) serum concentrations in 156 patients with stable coronary artery disease. They underwent a treadmill exercise test (TET) before and after 3 months of TMZ treatment. IL-2 and IL-8 concentrations were determined before and after each TET. Before treatment, TET did not influence IL-2 concentrations, whereas IL-8 concentrations increased. TMZ treatment led to a decrease in IL-2 concentrations before TET, as well as it prevented the increase of IL-8 following the second TET. Obtained results confirmed the improvement in TET performance during TMZ treatment and they revealed a significant influence of TMZ on IL-2 and IL-8 concentrations both before and after TET. These changes may reflect potential anti-inflammatory effects of TMZ.

Using Gene Expression Analysis to Examine Changes in Loneliness, Depression and Systemic Inflammation in Lonely Chronically Ill Older Adults

Purpose

The purpose of this study was to evaluate the effectiveness of LISTEN (Loneliness Intervention) on loneliness, depression, physical health, systemic inflammation, and genomic expression in a sample of lonely, chronically ill, older adults.

Methods

This was a prospective, longitudinal randomized trial of LISTEN, a novel intervention based on theories of narrative and cognitive restructuring to target specific aspects of loneliness. Twenty-three older, lonely, chronically ill adults were recruited from a family medicine clinic in West Virginia. Participants were randomized to two groups, 13 in LISTEN group (Loneliness Intervention) and 10 in attention control (healthy aging education). Participants attended an enrollment session where they completed consent, survey data (including sociodemographics and chronic illness diagnoses), baseline physical measures, and blood sampling for gene expression analysis. After completing the 5 weekly sessions, all participants attended a 12 week post data collection meeting (17 weeks post-baseline) for survey completion, physical measures and blood sampling.

Results

The results of this study show that the LISTEN intervention improves measures of physical and psychosocial health. Specifically, subjects enrolled in LISTEN showed reductions in systolic blood pressure, as well as decreased feelings of loneliness and depression. These changes may be due, in part, to a reduction in systemic inflammation, as measured by interleukin-2.

Conclusion

This study provides support for the use of LISTEN in reducing loneliness in chronically ill, older adults. Further, while some of our results are inconclusive, it provides rationale to expand our study population to evaluate the relationship between loneliness and systemic inflammation. In the future, enhancing knowledge about the relationships among loneliness, chronic illness, systemic inflammation, and gene expression of these particular targets, and how these relationships may change over time with intervention will inform translation of findings to clinical settings.

Lymphocyte subpopulations in myocardial infarction: a comparison between peripheral and intracoronary blood

The frequency and profile of lymphocyte subsets within the culprit coronary artery were investigated in 33 patients with myocardial infarction and compared to their systemic circulating counterparts. T cell subsets including CD4⁺CD28null, activated and regulatory T-cells, TH1/TH2/TH17 phenotypes, NK and B-cells were studied in intracoronary (IC) and arterial peripheral blood (PB) samples. CD4⁺CD28null T-lymphocytes were significantly increased in IC compared to PB (3.7 vs. 2.9 %, p < 0.0001). Moreover, patients with more than 6 h of evolution of STEMI exhibited higher levels of CD4⁺CD28null T-cells suggesting that this subset may be associated with more intense myocardial damage. The rare NK subpopulation CD3⁻CD16⁺CD56⁻ was also increased in IC samples (5.6 vs. 3.9 %, p = 0.006). CD4⁺CD28null T-cells and CD3⁻CD16⁺CD56⁻ NK subpopulations were also associated with higher CK levels. Additionally, IFN-γ and IL10 were significantly higher in IC CD4⁺ lymphocytes. Particular immune cell populations with a pro-inflammatory profile at the site of onset were increased relative to their circulating counterparts suggesting a pathophysiological role of these cells in plaque instability, thrombi and myocardial damage.

Heat-sensitive moxibustion attenuates the inflammation after focal cerebral ischemia/ reperfusion injury

Heat-sensitive moxibustion has neuroprotective effects against focal cerebral ischemia/reperfusion injury, however its mechanism of action remains unclear. In this study, rat models of focal cerebral ischemia/reperfusion injury were treated with suspended moxibustion at acupoint Dazhui (DU14) for 35 minutes. Results showed that suspended moxibustion decreased infarct volume, reduced cortical myeloperoxidase activity, and suppressed serum levels of proinflammatory cytokines in rats with focal cerebral ischemia/reperfusion injury. Our experimental findings indicated that heat-sensitive moxibustion can attenuate inflammation and promote repair after focal cerebral ischemia/reperfusion injury.

[Association between inflammatory markers and microbial translocation in patients with human immunodeficiency virus infection taking antiretroviral treatment]

BACKGROUND AND OBJECTIVE

Inflammatory biomarkers are increased in patients with human immunodeficiency virus (HIV) infection. Antiretroviral treatment (ART) improves some parameters but do not normalize them. The aim of this study is to determine those factors (including microbial translocation) associated with higher inflammation in HIV treated patients.

PATIENTS AND METHODS

Transversal observational study.

INCLUSION CRITERIA

HIV patients receiving ART with an HIV viral load (VL)<400 copies/mL. Selection of patients: consecutively between November 2011 and January 2012. Main variable: plasma levels of interleukin 6 (IL-6) and tumour necrosis factor α (TNF-α). Main explanatory variable: microbial translocation markers (16S ribosomal DNA and sCD14). Patients with IL-6 or TNF-α levels above percentile 75 (group 1) were compared with the rest of patients (group 2). Odds ratio (OR) were determined.

RESULTS

Eighty-one patients were included (73% male, median age 45 years, 48% stage C). Twenty-six percent had chronic hepatitis C. Median CD4 cell was 493/mm(3) and 30% had detectable HIV VL. 16S ribosomal DNA was detected in 21% of patients. Factors associated with the higher levels of inflammatory markers were 16S ribosomal DNA (OR 77, P<.0001), sCD14 levels (P<.0001) and history of cardiovascular disease (OR 15, P<.01). In multivariate analysis, associations remained for 16S ribosomal DNA (OR 62, P<.0001) and previous cardiovascular disease (OR 25, P<.01).

CONCLUSIONS

In patients with HIV infection receiving treatment, the higher levels of inflammatory markers are associated with microbial translocation and past cardiovascular events.

Atherosclerosis is associated with multiple pathogenic mechanisms in HIV-infected antiretroviral-naive or treated individuals

OBJECTIVES

HIV-infected patients have a greater burden of sub-clinical and clinical atherosclerotic disease compared to the general population. The primary objective of this study was to compare the relative roles of inflammation, endothelial alterations, and metabolic factors in the induction and maintenance of atherosclerosis in antiretroviral therapy (ART)-treated or ART-naive patients.

DESIGN

Cross-sectional study; 79 HIV-infected patients (55 ART-treated and 24 naive individuals) were consecutively enrolled. In both groups, nearly 50% of the individuals had a high cardiovascular risk (Framingham value >20%).

METHODS

Echo-Doppler [intima-media thickness (IMT)], inflammatory, thrombophilic, endothelial, metabolic indexes, and cholesterol efflux molecules were evaluated. Multivariate analysis adjusted for age, CD4 nadir, BMI, and Framingham's score were used to analyze the results.

RESULTS

A complex pathogenesis drives atherogenesis in HIV infection. Thus, whereas inflammation could be responsible for this process in ART-naive individuals, metabolic factors [low-density lipoprotein (LDL), apolipoprotein B (ApoB), lipoprotein A] seem to play a more prevalent role in ART-treated patients. Notably, ABCA-1, an ATP-binding transporter cassette protein involved in cholesterol efflux, which is inhibited by Nef, is up-regulated in ART-treated individuals.

CONCLUSION

Atherosclerosis in HIV infection results from the interaction of multiple factors: an inflammatory and HIV-driven disease could prevail in the absence of therapy; metabolic, non-inflammatory causes may be more important in patients undergoing therapy. Approaches to atherosclerotic disease in HIV infection should consider these differences.

Decreased plasma IL-35 levels are related to the left ventricular ejection fraction in coronary artery diseases

Background

Accumulating evidence shows that the novel anti-inflammatory cytokine IL-35 can efficiently suppress effector T cell activity and alter the progression of inflammatory and autoimmune diseases. The two subunits of IL-35, EBI3 and p35, are strongly expressed in human advanced plaque, suggesting a potential role of IL-35 in atherosclerosis and coronary artery disease (CAD). However, the plasma levels of IL-35 in patients with CAD have yet to be investigated.

Methods

Plasma IL-35, IL-10, TGF-β1, IL-12 and IL-27 levels were measured using an ELISA in 43 stable angina pectoris (SAP) patients, 62 unstable angina pectoris (UAP) patients, 56 acute myocardial infarction (AMI) patients and 47 chest pain syndrome patients as a control group.

Results

The results showed that plasma IL-35 levels were significantly decreased in the SAP group (90.74±34.22 pg/ml), the UAP group (72.20±26.63 pg/ml), and the AMI group (50.21±24.69 pg/ml) compared with chest pain syndrome group (115.06±32.27 pg/ml). Similar results were also demonstrated with IL-10 and TGF-β1. Plasma IL-12 and IL-27 levels were significantly increased in the UAP group (349.72±85.22 pg/ml, 101.75±51.42 pg/ml, respectively) and the AMI group (318.05±86.82 pg/ml, 148.88±68.45 pg/ml, respectively) compared with chest pain syndrome group (138.68±34.37 pg/ml, 63.60±22.75 pg/ml, respectively) and the SAP group (153.84±53.86 pg/ml, 70.84±38.77 pg/ml, respectively). Furthermore, lower IL-35 levels were moderately positively correlated with left ventricular ejection fraction (LVEF) in CAD patients (R = 0.416, P<0.01), whereas higher IL-27 levels were weakly negatively correlated with LVEF in CAD patients(R = −0.205, P<0.01).

Conclusions

The results of the present study show that circulating IL-35 is a potentially novel biomarker for coronary artery disease. Regulating the expression of IL-35 also provides a new possible target for the treatment of atherosclerosis and CAD.

Persistent accumulation of interferon-γ-producing CD8+CD56+ T cells in blood from patients with coronary artery disease

OBJECTIVE

There is emerging evidence for CD8(+) T cell alterations in blood from patients with coronary artery disease (CAD). We examined whether the distribution and phenotype of CD8(+)CD56(+) T cells differed according to the clinical manifestation of CAD.

METHODS

Patients with acute coronary syndrome (ACS, n = 30), stable angina (SA, n = 34) and controls (n = 36) were included. Blood was collected before and up to 12 months after referral for coronary investigation. CD8(+)CD56(+) T cells were assessed by flow cytometry for expression of surface markers, apoptosis, and intracellular expression of cytokines.

RESULTS

The proportions of CD8(+)CD56(+) T cells were significantly higher in both ACS and SA patients compared with controls, and remained so after 3 and 12 months. This was independent of age, sex, systemic inflammation and cytomegalovirus seropositivity. CD8(+)CD56(+) T cells differed from CD8(+)CD56(-) T cells in terms of lower CD28 expression and fewer apoptotic cells. Both CD8(+) T cell subsets were positive for interferon (IFN)-γ and tumor necrosis factor, although IFN-γ was significantly more confined to the CD8(+)CD56(+) T cells.

CONCLUSION

The persistent accumulation of CD8(+)CD56(+) T cells in ACS and SA patients share several features with immunological aging. It also contributes to a larger IFN-γ(+) pool in blood, and may thereby hypothetically drive the atherosclerotic process in a less favorable direction.

Lymphocyte subpopulations in lymph nodes and peripheral blood: a comparison between patients with stable angina and acute coronary syndrome

Objective

Atherosclerosis is characterized by a chronic inflammatory response involving activated T cells and impairment of natural killer (NK) cells. An increased T cell activity has been associated with plaque instability and risk of acute cardiac events. Lymphocyte analyses in blood are widely used to evaluate the immune status. However, peripheral blood contains only a minor proportion of lymphocytes. In this study, we hypothesized that thoracic lymph nodes from patients with stable angina (SA) and acute coronary syndrome (ACS) might add information to peripheral blood analyses.

Methods

Peripheral blood and lymph nodes were collected during coronary by-pass surgery in 13 patients with SA and 13 patients with ACS. Lymphocyte subpopulations were assessed by flow cytometry using antibodies against CD3, CD4, CD8, CD19, CD16/56, CD25, Foxp3, CD69, HLA-DR, IL-18 receptor (R) and CCR4.

Results

Lymph nodes revealed a lymphocyte subpopulation profile substantially differing from that in blood including a higher proportion of B cells, lower proportions of CD8⁺ T cells and NK cells and a 2-fold higher CD4/CD8 ratio. CD4⁺CD69⁺ cells as well as Foxp3⁺ regulatory T cells were markedly enriched in lymph nodes (p<0.001) while T helper 1-like (CD4⁺IL-18R+) cells were more frequent in blood (p<0.001). The only significant differences between ACS and SA patients involved NK cells that were reduced in the ACS group. However, despite being reduced, the NK cell fraction in ACS patients contained a significantly higher proportion of IL-18R⁺ cells compared with SA patients (p<0.05).

Conclusion

There were several differences in lymphocyte subpopulations between blood and lymph nodes. However, the lymphocyte perturbations in peripheral blood of ACS patients compared with SA patients were not mirrored in lymph nodes. The findings indicate that lymph node analyses in multivessel coronary artery disease may not reveal any major changes in the immune response that are not detectable in blood.

Multiple aberrations in shared inflammatory and oxidative & nitrosative stress (IO&NS) pathways explain the co-association of depression and cardiovascular disorder (CVD), and the increased risk for CVD and due mortality in depressed patients

There is evidence that there is a bidirectional relationship between major depression and cardiovascular disorder (CVD): depressed patients are a population at risk for increased cardiac morbidity and mortality, and depression is more frequent in patients who suffer from CVD. There is also evidence that inflammatory and oxidative and nitrosative stress (IO&NS) pathways underpin the common pathophysiology of both CVD and major depression. Activation of these pathways may increase risk for both disorders and contribute to shared risk. The shared IO&NS pathways that may contribute to CVD and depression comprise the following: increased levels of pro-inflammatory cytokines, like interleukin-1β (IL-1β), IL-2, IL-6, IL-8, IL-12, tumor necrosis factor-α, and interferon-γ; T cell activation; increased acute phase proteins, like C-reactive protein, haptoglobin, fibrinogen and α1-antitrypsin; complement factors; increased LPS load through bacterial translocation and subsequent gut-derived inflammation; induction of indoleamine 2,3-dioxygenase with increased levels of tryptophan catabolites; decreased levels of antioxidants, like coenzyme Q10, zinc, vitamin E, glutathione and glutathione peroxidase; increased O&NS characterized by oxidative damage to low density lipoprotein (LDL) and phospholipid inositol, increased malondialdehyde, and damage to DNA and mitochondria; increased nitrosative stress; and decreased ω3 polyunsaturated fatty acids (PUFAs). The complex interplay between the abovementioned IO&NS pathways in depression results in pro-atherogenic effects and should be regarded as a risk factor to future clinical CVD and due mortality. We suggest that major depression should be added as a risk factor to the Charlson "comorbidity" index. It is advised that patients with (sub)chronic or recurrent major depression should routinely be assessed by serology tests to predict if they have an increased risk to cardiovascular disorders.

Inflammatory cytokines imbalance in the very early phase of acute coronary syndrome: correlations with angiographic findings and in-hospital events

The aim of this study is to investigate the release of some inflammatory cytokines (Cks) during the very early phase (first 24 h) of acute coronary syndrome (ACS). Twenty-six consecutive subjects admitted to coronary care unit with ACS underwent serial blood sampling in order to evaluate concentrations of interleukin (IL)-2, IL-10, IL-18, tumor necrosis factor (TNF)-α, and interferon (IFN)-γ. Blood samples were taken within 6 h after onset of chest pain (T₀), at 12 h (T₁), and at 24 h (T₂). Patients were thus divided into four groups comparing pro-inflammatory Ck release (IL-2, TNF-α, and IFN-γ) and anti-inflammatory activity (IL-10). Clinical features, risk factors, incidence of adverse events, and coronary angiography findings were compared with Ck activation. Ck levels were significantly increased if compared with baseline. Subjects with marked inflammatory response showed a higher incidence of left anterior descending coronary disease (IL-2, p < 0.001; TNF-α and IFN-γ, p < 0.05) and more often incurred early complications (IL-2, p < 0.05; IFN-γ, p < 0.001). A correlation was detectable between IL-18 levels and myocardial enzyme release (creatine kinase, r = 0.47; lactate dehydrogenase, r = 0.54; troponin I, r = 0.58; p < 0.05). TNF-α levels were associated with a worse prognosis at follow-up (Log rank, p < 0.05). A Ck activation characterizes the early phase of ACS. Early inflammatory reaction seems to correlate with coronary disease and adverse events.

Influenza vaccination promotes stable atherosclerotic plaques in apoE knockout mice

OBJECTIVE

Current evidence suggests a relationship between seasonal Influenza viral infection and cardiovascular disease (CVD). Experimental animals inoculated with Influenza A virus have shown to develop thrombotic complications similar to those seen in humans. Conversely, several epidemiological studies and clinical trials have suggested that Influenza vaccination may have a protective effect on CVD. However, the potential mechanisms behind this protective effect remain unstudied. We aimed to study the effect of Influenza vaccination on atherosclerotic plaque development in apoE(-/-) mice.

METHODS AND RESULTS

The effect of immunization with increasing doses of Influenza vaccine (0.38, 1.8, 9 and 45 μg/0.5 mL Vaxigrip®, Sanofi-Aventis) on atherogenesis was compared with that of animals immunized with Pneumo23® (pneumococcus vaccine, Sanofi-Aventis) and control group inoculated with phosphate buffered saline (PBS). Animals vaccinated with 45 μg/0.5 mL Vaxigrip®, (the same dose used to immunize humans adults against Influenza) developed smaller atherosclerotic lesions with lower lipid content but richer in smooth muscle cells and collagen when compared with control animals. Concomitantly, they showed lower levels of interferon gamma (IFNγ), interleukin (IL)-2 and tumor necrosis factor alpha (TNFα) but higher levels of IL-4. Furthermore, we found increased levels of anti-Influenza immunoglobulin (Ig) G1 or anti-Pneumo23® IgM specific antibodies in a time and dose dependent fashion in animals immunized with these vaccines.

CONCLUSIONS

These results indicate that vaccination against Influenza may protect against the development of CVD by promoting smaller and stable atherosclerotic plaques and by inducing atheroprotective immune responses.

Smoking and atherosclerotic cardiovascular disease: part II: role of cigarette smoking in cardiovascular disease development

Potential mechanisms and biomarkers of atherosclerosis related to cigarette smoking - a modifiable risk factor for that disease - are discussed in this article. These include smoking-associated inflammatory markers, such as leukocytes, high-sensitivity C-reactive protein, serum amyloid A, ICAM-1 and IL-6. Other reviewed markers are indicative for smoking-related impairment of arterial endothelial function (transcapillary leakage of albumin, inhibition of endogenous nitric oxide synthase activity and reduced endothelium-dependent vasodilation) or point to oxidative stress caused by various chemicals (cholesterol oxidation, autoantibodies to oxidized low-density lipoprotein, plasma levels of malondialdehyde and F(2)-isoprostanes and reduced antioxidant capacity). Smoking enhances platelet aggregability, increases blood viscosity and shifts the pro- and antithrombotic balance towards increased coagulability (e.g., fibrinogen, von Willebrand factor, ICAM-1 and P-selectin). Insulin resistance is higher in smokers compared with nonsmokers, and hemoglobin A1c is dose-dependently elevated, as is homocysteine. Smoke exposure may influence the kinetics of markers with different response to transient or chronic changes in cigarette smoking behavior.

Homocysteine and pro-inflammatory cytokine concentrations in acute heart disease

Inflammation is involved in development and progression of atherosclerosis. Interleukin-2 (IL-2) and interleukin-6 (IL-6) have been correlated with various cardiovascular diseases. Hyperhomocysteinemia is an important risk factor for atherosclerosis and thrombotic disease. Recent studies have demonstrated that homocysteine (Hcy) enhances productions of several pro-inflammatory cytokines. In the light of these findings, we decided to determine if any relationship exists between IL-2 and IL-6, the pro-inflammatory cytokines, and total homocysteine (tHcy) in acute coronary syndrome (ACS). A total of 102 patients with ACS and 90 healthy subjects were included in the study. The levels of tHcy, IL-2 and IL-6 were higher and folic acid was lower in patients as compared with those of controls. Furthermore, data of the area under ROC plot for IL-2 demonstrated that IL-2 had higher sensitivity. These data suggest that enhanced inflammation may be associated with tHcy-related cardiovascular disease.

Interleukin-6 and acute coronary syndrome

The designation of atherosclerosis as a chronic inflammatory process represents an exciting and logical paradigm shift for cardiologists. Plasma concentrations of interleukin-6 (IL-6) and its hepatic by-product C-reactive protein (CRP) appear to reflect the intensity of occult plaque inflammation and by inference may determine vulnerability to rupture. Indeed, circulating IL-6 levels are elevated in patients with acute myocardial infarction (AMI), and also in patients with unstable, but not with stable angina. Coronary sinus IL-6 concentrations are also increased after percutaneous coronary intervention (PCI), and late restenosis correlates with an increase in IL-6 concentration after the procedure, indicating that IL-6 expression may be not only related to instability of atheromatous plaques, but also to the formation of restenotic lesions after PCI. These observations suggest the advantage of screening for circulating IL-6 concentration and the use of anti-inflammatory treatment for those thought be at high risk to reduce the risk of future AMI.

Cytokines and coronary artery disease: the state of the art

Initiation and progression of coronary atherosclerosis has been associated with inflammation and cytokines balance. The objective of this study is to understand the role of cytokines in the pathophysiology and management of coronary artery disease. Coronary artery disease has been revisited with revision of the pertinent published articles in the Medline, Scopus, and EBSCO Host research from 1987 to 2007. The 2 groups of cytokines (proinflammatory and anti-inflammatory) have been detected in human atherosclerotic plaques. The balance between the 2 groups may reflect the intensity of occult plaque inflammation and the vulnerability to rupture. Multiple studies have determined that a diverse set of proinflammatory biomarkers can furnish prognostic information beyond the traditional risk factors. Inflammatory responses after coronary revascularization are known to play key role in vascular lesion formation early in atherosclerosis and restenosis. Clinical utilization of cytokines remains promising yet incompletely explored and need more studies.

Comparison of serum levels of inflammatory markers and allelic variant of interleukin-6 in patients with acute coronary syndrome and stable angina pectoris

OBJECTIVES

Although the relationship between atherosclerosis and inflammatory cells has been recognized in recent years, the effect of interleukin-6 (IL-6) genetic variants associated with atherosclerosis is still controversial. Therefore, we investigated the association between IL-6 polymorphism and levels of IL-6 in patients with coronary artery disease (CAD).

METHODS

We conducted a case-control study on 294 unrelated participants who were referred to the cardiology department of the university hospital for coronary angiography because of suspected ischemic heart disease. Group I comprised patients with clinically acute coronary syndrome, and group II comprised patients (individuals matched for age and sex) with clinically stable angina pectoris; both groups were categorized, based on their angiographic findings, as either having angiographically documented less extensive CAD (1 vessel narrowed) or extensive CAD (> or =2 vessels narrowed). They were studied to examine effect of the IL-6 gene variants in CAD. Genotyping was determined by polymerase chain reaction.

RESULTS

The IL-6 G/C-174 polymorphism was found in 19 of 106 (18%) in group I and in four of 188 (2%) in group II (P<0.001). Median IL-6 levels were significantly higher in group I (6.7+/-13.6 pg/ml) than in group II (4.1+/-3.8 pg/ml) (P<0.05). In addition, high sensitivity C-reactive protein levels were significantly higher in group I (8.2+/-6.2 mg/dl) than in group II (4.6+/-3.4 mg/dl) (P<0.001).

CONCLUSION

These results demonstrated that the presence of the IL-6 G/C-174 polymorphism and increased IL-6 and high sensitivity C-reactive protein levels are strongly associated with the inflammatory system and the course of clinical and hemodynamically significant CAD.

Conjugated linoleic acid supplementation reduces peripheral blood mononuclear cell interleukin-2 production in healthy middle-aged males

Conjugated linoleic acid (CLA) refers to geometric and positional isomers of linoleic acid. Animal studies have shown that CLA modulates the immune system and suggest that it may have a therapeutic role in inflammatory disorders. This double-blind placebo-controlled intervention trial investigated the effects of CLA supplementation on indices of immunity relating to cardiovascular disease (CVD) in a cohort of healthy middle-aged male volunteers. Subjects were randomly assigned to supplement their diet with 2.2 g 50:50 isomeric blend of cis 9, trans 11 (c9, t11)-CLA and trans 10, cis 12 (t10, c12)-CLA or placebo daily for 8 weeks. Interleukin (IL) 2, IL-10 and tumour necrosis factor (TNF) alpha were measured in the supernatant of cultured unstimulated and concanavalin A (Con A)-stimulated peripheral blood mononuclear cells (PBMC) by ELISA. Serum IL-6 and plasma CRP were measured by ELISA and plasma fibrinogen by automated clotting assay. Gene expression was investigated by real-time RT-PCR. CLA supplementation significantly reduced Con A-stimulated PBMC IL-2 secretion (37.1%; P=.02). CLA supplementation had no significant effect on transcription of IL-2. CLA supplementation had no direct significant effects on PBMC TNFalpha or IL-10 secretion. Other inflammatory markers associated with CVD, including IL-6, CRP and fibrinogen, were not affected by CLA supplementation. This study showed that CLA supplementation reduced PBMC IL-2 secretion from Con A-stimulated PBMC but lacked effect on other markers of the human inflammatory response.

Inflammatory Cytokine Imbalance after Coronary Angioplasty: Links with Coronary Atherosclerosis

AIM

To investigate release of some inflammatory cytokines (Cys) after coronary angioplasty and its links with coronary atherosclerosis.

METHODS

Twenty-seven consecutive subjects with acute coronary syndrome (ACS) who underwent percutaneous coronary intervention (PCI) were enrolled in the study: serial blood samples were taken in order to evaluate plasma concentrations of Interleukin (IL)-2, IL-10, IL-18, TNFalpha, and IFNgamma just before PCI at 12 and 24 hours. Patients were then divided, considering balance between each inflammatory Cy and IL-10, an antiinflammatory Cy, into four groups, ranging from a prevalent antiinflammatory response (stable inflammatory Cy-increasing IL-10 values) to a marked inflammatory imbalance (increasing inflammatory Cy-stable IL-10 values).

RESULTS

All Cys showed significant increases in plasma concentrations if compared with baseline values. Release curves were not significantly different when comparing subjects with ST-elevation myocardial infarction (STEMI) versus unstable angina-non-STEMI (UA-NSTEMI), diabetics versus controls. Subjects with marked inflammatory response showed a higher incidence of stenosis on left anterior descending (LAD) coronary artery (IL-2 chi(2) and IFNgamma P < 0.05); Cy release was higher in patients with multivessel coronary disease (IL-2 and IFNgamma, ANOVA P < 0.01). Correlations were also referable between Cys and myocardial enzyme release. Subjects treated with sirolimus-eluting stents (SES) showed significantly lower Cy periprocedure ratio if compared with those treated with bare metal stents.

CONCLUSIONS

A significant Cy release is detectable after PCI: inflammatory response seems to correlate with both PCI due to plaque instabilization and coronary atherosclerosis. A blunted inflammatory response is detectable in subjects treated with SES.

An inflammatory pathway of IFN-gamma production in coronary atherosclerosis

Inflammation is associated with the pathogenesis of coronary atherosclerosis, although the mechanisms remain unclear. We investigated whether cytokine secretion by innate immune responses could contribute to the production of proarteriosclerotic Th1-type cytokines in human coronary atherosclerosis. Cytokines were measured by ELISA in the plasma of patients with coronary atherosclerosis undergoing cardiac catheterization. IL-18 was detected in all subjects, whereas a subset of patients demonstrated a coordinated induction of other IFN-gamma-related cytokines. Specifically, elevated plasma levels of IL-12 correlated with that of IFN-gamma and IFN-gamma-inducible chemokines, defining an IFN-gamma axis that was activated independently of IL-6 or C-reactive protein. Systemic inflammation triggered by cardiopulmonary bypass increased plasma levels of the IFN-gamma axis, but not that of IL-18. Activation of the IFN-gamma axis was not associated with acute coronary syndromes, but portended increased morbidity and mortality after 1-year follow-up. IL-12 and IL-18, but not other monokines, elicited secretion of IFN-gamma and IFN-gamma-inducible chemokines in human atherosclerotic coronary arteries maintained in organ culture. T cells were the principal source of IFN-gamma in response to IL-12/IL-18 within the arterial wall. This inflammatory response did not require, but was synergistic with and primed for TCR signals. IL-12/IL-18-stimulated T cells displayed a cytokine-producing, nonproliferating, and noncytolytic phenotype, consistent with previous descriptions of lymphocytes in stable plaques. In contrast to cognate stimuli, IL-12/IL-18-dependent IFN-gamma secretion was prevented by a p38 MAPK inhibitor and not by cyclosporine. In conclusion, circulating IL-12 may provide a mechanistic link between inflammation and Th1-type cytokine production in coronary atherosclerosis.

Expression of monocyte and lymphocyte adhesion molecules is increased in isolated coronary artery ectasia

BACKGROUND

Coronary artery ectasia is defined as localized or diffuse dilation of the coronary arteries exceeding the 1.5-fold of normal adjacent segment. Scarce data are available about the role of inflammation in coronary artery ectasia. In the present study, we aimed to evaluate the expression of CD11b and CD45 adhesion molecules in peripheral blood granulocytes, monocytes and lymphocytes from the patients with coronary artery ectasia as possible indicators of inflammation.

METHOD

The study consisted of 14 patients who had angiographically normal coronary arteries with coronary artery ectasia and 13 age and sex-matched controls without coronary artery ectasia. Cell surface adhesion molecules were detected by direct immunofluorescence evaluated by flow cytometry using monoclonal antibodies tagged with fluorescent markers. Venous blood samples were taken after coronary angiography.

RESULTS

Mean fluorescence intensity of CD45 (33.8+/-3.1 vs. 13.0+/-0.7, P<0.001) and CD11b (39.1+/-13.5 vs. 19.5+/-1.32, P<0.001) on the monocyte surface of patients with coronary artery ectasia were higher than those of controls. Similarly in patients with coronary artery ectasia, the expression of CD11b (7.5+/-0.61 vs. 5.6+/-0.2, P=0.009) and CD45 (47.5+/-3.6 vs. 36.2+/-2.5, P=0.02) on lymphocytes was also significantly higher than those of controls.

CONCLUSION

Increased levels of cellular adhesion molecules in patients with coronary artery ectasia may be an indicator of endothelial activation and inflammation and are likely to be in the causal pathway leading to coronary artery ectasia.

Effects of interleukin-2 on the mechanical restitution and post-rest contraction in rat ventricular papillary muscle

To determine whether application of interleukin-2 (IL-2) alters function of sarcoplasmic reticulum (SR), we measured mechanical restitution and post-rest potentiation (PRP) in isolated rat papillary muscles. Mechanical restitution curves were constructed by interpolating extrasystoles at different test intervals following a train of steady state beats. In control group, the maximal PRP was reached after 60-120s of rest and the maximal potentiation factor was 2.36 +/- 0.23. IL-2 at 200 U/ml decreased the steady-state force of contraction to 56.4 +/- 7.2% of pre-drug control. But the time constant of recovery of steady-state force was not altered after IL-2. IL-2 decreased PRP at all intervals, shifted the potentiation curve parallel to lower values. But the potentiation was enhanced when compared with pre-rest control value in the presence of IL-2. In papillary muscle treated with IL-2, the onset of maximal PRP was delayed and the potentiation factor after 300s was 4.72 +/- 0.58 times that at the steady-state. Recirculation fraction of calcium calculated from the decay of PRP was 0.78 +/- 0.09 in control and 0.59 +/- 0.08 after IL-2 treatment. We conclude that IL-2 decreases the function of SR, which suggests that an impaired function of SR may contribute to the negative inotropic effect of IL-2.

Inflammatory markers in a 2-year follow-up of coronary artery disease

Our study was designed in an attempt to determine the dynamics of changes in serum tumor necrosis factor (TNF)-alpha, soluble forms of its receptors (sTNFR 1, sTNFR 2), and adhesion molecules (sE-selectin, sP-selectin, sVCAM-1, sICAM-1) over a 2-year follow-up of patients with coronary artery disease (CAD). The study involved 70 patients with stable CAD (stable angina class II/III according to the Canadian Cardiovascular Society) and 20 apparently healthy subjects. Over the follow-up period a marked attenuation of angina (P<0.001) was observed. Interventional treatment (percutaneous coronary intervention, coronary artery bypass grafting) was used in 53 CAD patients. Laboratory analysis revealed a significant decrease of serum TNF-alpha and sTNFR1 at 2 years (TNF-alpha: 12.1+/-0.7 pg/ml; sTNFR 1: 1306+/-46 pg/ml) as compared to baseline levels (16.5+/-0.7 pg/ml, P=0.030; 1551+/-82 pg/ml, P=0.048, respectively). The levels of sP-selectin (159+/-7 vs 201+/-14 ng/ml, P<0.01) and sICAM-1 (133+/-4 vs 153+/-6 ng/ml, P<0.05) were found to be significantly increased as compared to the baseline. Interventional procedures resulted in suppression of both cytokine (TNF-alpha, sTNFR 2) and adhesion molecule (sE-selectin, sP-selectin) activation in the CAD group. The baseline and post-follow-up TNF-alpha and sTNFR 1 levels showed persistent elevation in CAD patients as compared to the controls (9.0, 956.3 pg/ml, respectively; P<0.01). There were no differences between baseline and final cytokines and adhesion molecules in healthy subjects. The course of CAD as modified by a clinically effective therapy is characterized by changes of immune markers activation. Revascularization seems to be an important factor suppressing both cytokine and adhesion molecule activation in CAD patients.

Markers of inflammation and atherosclerosis in Egyptian patients with systemic lupus erythematosus

BACKGROUND

Cardiovascular events are markedly increased in systemic lupus erythematosus (SLE) and the mechanism of atherogenesis remains poorly understood. Low-grade inflammation and endothelial dysfunction play pivotal roles in the initiation, progression and propagation of the atherosclerotic process. Several methods have been employed to assess endothelial function, among them the measurement of biomarkers of endothelial activation and dysfunction (intercellular adhesion molecule (ICAM)-1). Since then, it has been reported that such biomarkers play a more important role than traditional risk factors in cardiovascular disease.

OBJECTIVE

To measure (tumour necrosis factor (TNF)-alpha, interleukin (IL)-6 and ICAM-1) levels as markers of inflammation and atherosclerosis in 40 Egyptian patients with SLE with various degrees of activity in comparison with 20 healthy volunteers, and to investigate their relationship to disease activity and hypertension.

METHODS

Sixty subject (40 with SLE and 20 healthy controls) were the subject of this study, their clinical disease activity was scored according to the SLE Disease Activity Index (SLEDAI), and serum sampling was obtained for TNF-alpha, IL-6 and ICAM-1 level assay. Renal biopsy was carried out and examined by light microscopy. The mean level of TNF-alpha, IL-6 and ICAM-1 were significantly higher in SLE patients with active disease (766.95 +/- 357.82 Pg/mL, 135.4 +/- 54.23 Pg/mL, 826.05 +/- 367.1 Pg/mL) when compared with those with inactive disease (314.01 +/- 100.87 Pg/mL, 47.33 +/- 18.61 pg/mL, 441.33 +/- 225.19 Pg/mL) and healthy control volunteers (172.7 +/- 39.19 Pg/mL, 21.15 +/- 10.99 Pg/mL, 111.5 +/- 17.36 Pg/mL), respectively. Furthermore, these levels were significantly higher in hypertensive (614.08 +/- 333.05 Pg/mL, 107.86 +/- 54.96 Pg/mL and 862.13 +/- 333.29 Pg/mL) compared to normotensive patients (267.5 +/- 112.72 Pg/mL, P = 0.008, 35.75 +/- 20.26 Pg/mL, P = 0.02I, and 337.25 +/- 235.62 Pg/mL, P = 0.02) for TNF-alpha, IL-6 and ICAM, respectively. There were no statistically significant difference regarding age, sex, smoking, cholesterol and high-density lipoprotein (HDL) levels between hypertensive and normotensive patients.

CONCLUSION

A high concentration of soluble ICAM-1 in Egyptian patients with SLE and nephritis is reported here for the first time. Our finding of increased concentrations of TNF-alpha, IL-6 and ICAM-1 in Egyptian patients with SLE and lupus nephritis underlines the importance of inflammation and endothelial involvement in this disorder, but their predictive value in the disease monitoring needs to be further studied.

Interleukin-6 and the risk of future cardiovascular events in patients with angina pectoris and/or healed myocardial infarction

The aim of this study was to evaluate the prognostic value of interleukin-6 (IL-6) for myocardial infarction (MI) and mortality in a population with stable coronary artery disease (CAD) during a mean period of 6.3 years. IL-6 is a major proinflammatory cytokine of acute phase response; elevated levels are associated with worse prognosis in unstable angina and after acute MI. However, data regarding its long-term prognostic value in stable CAD are limited and controversial. A nested case-control study design was used. Of 3,090 patients with stable CAD, 129 with an adequate blood sample for IL-6 and who reached the end points (MI or sudden death) were randomly selected. Each case was 1:1 matched with 129 controls (alive at the end of the study and free of cardiovascular events) according to age, gender, and treatment. Of the 129 cases, 113 had a MI as the initial event, and for the other 16 the initial event was sudden death. There were 8 patients who first had a MI and later died suddenly. IL-6 was significantly higher in cases (2.34 pg/ml) than in controls (1.65 pg/ml) (p = 0.0004). IL-6 was significantly correlated with C-reactive protein (r = 0.2, p = 0.002); a borderline significance was also found for fibrinogen (r = 0.11, p = 0.07). Each increase of 1 pg/ml in IL-6 was associated with a 1.70 (range 1.23 to 2.45) increased relative odds of subsequent MI or sudden death. Events rate per 1,000 patients-years for the 5 quintiles of IL-6 were 72.26, 89.61, 79.76, 142.53, and 181.08, respectively (p <0.0001). A significantly higher risk in the upper quintile was found (odds ratio, 3.44; 95% confidence interval 1.57 to 8.13). In conclusion, elevated IL-6 levels are strongly associated with future cardiac events and mortality in a population with stable CAD during a long-term follow-up.

Significance of changes in TNF-α and IL-10 levels in the progression of heart failure subsequent to myocardial infarction

We tested whether a decrease in the ratio of interleukin-10 (IL-10) to tumor necrosis factor-α (TNF-α) correlates with the decrease in cardiac function in heart failure. It has been suggested that TNF-α plays a role in the progression of heart failure, and the effect of TNF-α in many tissues is modulated by IL-10. Any relation of these two cytokines to heart failure has never been examined. Cardiac function was assessed by echocardiographic and hemodynamic techniques in coronary artery-ligated rats at 1, 4, 8, and 16 wk after myocardial infarction (MI). Membrane-bound and soluble fractions of TNF-α and IL-10 proteins, the ratio of TNF-α to IL-10, and TNF-α and IL-10 mRNA levels were analyzed. Losartan was used to modify cardiac function in rats 4 wk after MI to further validate the relation between the IL-10-to-TNF-α ratio and cardiac function. Cardiac function deteriorated with time in all coronary artery-ligated groups, with severe failure at 16 wk after MI. Membrane-bound and soluble TNF-α protein fractions were increased 1 and 4 wk after MI, whereas TNF -α mRNA was increased 4 and 8 wk after MI. Membrane-bound IL-10 protein and mRNA levels were decreased 4, 8, and 16 wk after MI. The decrease in the IL-10-to-TNF-α protein ratio in all coronary artery-ligated groups correlated with the depressed cardiac function. Losartan improved cardiac function, membrane-bound and soluble TNF-α and IL-10 protein levels, the ratio of IL-10 to TNF-α, and IL-10 mRNA. This study suggests that a decrease in IL-10 and IL-10-to-TNF-α ratio correlates with depressed cardiac function.

Helper T cells and atherosclerosis: the cytokine web

There is growing evidence regarding the importance of inflammation in the pathogenesis of atherosclerosis and its ultimate progression to the clinical syndromes. Recently there has been an increasing interest in the role of helper T (Th) cells in atherosclerosis. The Th cells act with the macrophages and the dendritic cells via the various cytokines in bringing about a variety of changes thus leading to the progression of atherosclerosis. Atherosclerotic lesions have been seen to have increased expression of type 1 helper T (TH1) cells together with increased levels of the Th1 related cytokines. It is mainly the cytokines involved with Th1 functioning that seem to show a prominent effect, with the whole process centred around interferon gamma, making it seem like every pathway and the cytokines involved lead to a final common pathway of interferon gamma secretion; the increase or decrease of which dictates the progression of atherosclerosis and its final manifestation as the clinical syndromes.

Immunomodulatory activity of a chymotrypsin inhibitor from Momordica cochinchinensis seeds

Serine protease inhibitors are widely distributed in the plant kingdom. Many of them have been purified and characterized from different species. While the physicochemical properties of these protease inhibitors have been extensively investigated, their biological effects, e.g. immunomodulatory effect, remain relatively unexplored. Recently, we isolated a chymotrypsin-specific inhibitor (MCoCI) from the seeds of Momordica cochinchinensis (Lour) Spreng (Family Cucurbitaceae), the traditional Chinese medicine known as Mubiezhi, which has been used as an antiinflammatory agent. In the present study, the effects of MCoCI on different types of cells of the immune system, including splenocytes, splenic lymphocytes, neutrophils, bone marrow cells and macrophages, were investigated. MCoCI was shown to possess immuno-enhancing and antiinflammatory effects. MCoCI could stimulate the proliferation of different cells of the immune system, e.g. splenocytes, splenic lymphocytes and bone marrow cells, in a manner comparable to that of Concanavalin A. Moreover, MCoCI could also suppress the formation of hydrogen peroxide in neutrophils and macrophages. These immunomodulatory effects may explain some of the therapeutic actions of Mubiezhi.

Intracellular expression of cytokines in peripheral blood from patients with atherosclerosis before and after carotid endarterectomy

OBJECTIVE

We investigated the possible association of intracellular cytokine profiles in peripheral mononuclear cells in whole blood from patients with carotid atherosclerosis in whom follow-up after carotid endarterectomy (CEA) showed the onset or progression of contralateral disease.

METHODS AND RESULTS

Intracellular expression of tumor necrosis factor (TNF)-alpha, interferon (IFN)-gamma, interleukin (IL)-1beta, IL-6, IL-8, IL-4 and IL-10 was determined in 43 patients with carotid atherosclerosis, at baseline and at 1, 3, 6 and 12 months after CEA, and in 16 healthy subjects. When follow-up ended patients were divided into two groups, those with cured or stable disease (no onset of disease or unchanged stenosis in the contralateral vessel) and those with progressive disease (onset of disease or increased stenosis in the contralateral vessel). In patients with cured or stable disease, cytokine-positive cells significantly decreased or remained unchanged (IL-8 and IL-10) during follow-up, whereas in patients with progressive disease they increased or remained unchanged (TNF-alpha). Multivariate ANOVA confirmed that the trend of cytokine expression between baseline and 12 months differed significantly in the two groups.

CONCLUSIONS

Intracellular expression of TNF-alpha, IFN-gamma, IL-1beta, IL-6, IL-8, IL-4 and IL-10 in peripheral mononuclear cells is associated with the outcome of contralateral disease after CEA.

Cytokines in acute coronary syndromes

The aim of this study was to show the presence of an imbalance between pro-inflammatory and anti-inflammatory mediators in patients affected by acute coronary syndromes (ACS). We evaluated the production in cultured and stimulated lymphomonocytes of interferon (IFN)gamma and tumor necrosis factor (TNF)alpha, which are well known to possess pro-inflammatory effects, and of interleukin (IL)10, which has been shown to have a protective anti-inflammatory activity, in two groups of 30 patients affected by acute myocardial infarction (AMI) and unstable angina (UA), compared with two equivalent groups of patients with stable angina (SA) and of healthy volunteers. We found a significant increase of IFNgamma and TNFalpha production (p<0.01) and a significant decrease of IL-10 production (p<0.01) in cultures of lymphomonocytes taken from patients with AMI and UA compared with SA patients and controls. No significant changes were found between AMI and UA patients and SA patients and controls. We conclude that a relevant imbalance in cytokine release is present in ACS, markedly favoring pro-inflammatory effects.

Chylomicron remnants regulate early growth response factor-1 in vascular smooth muscle cells

Early growth response factor-1 (Egr-1) is a zinc-finger transcription factor that induces genes that promote atherosclerosis. The goal of the present study was to determine whether Egr-1 expression is modulated by atherogenic, triglyceride rich lipoproteins known as chylomicron remnants. Chylomicron remnants induced Egr-1 mRNA and protein expression in rat cultured vascular smooth muscle cells (VSMCs) and activated extracellular signal-regulated kinase (ERK) 1/2 in VSMCs. Further, chylomicron remnant-induced Egr-1 expression was inhibited by PD98059, a selective inhibitor of MAPK kinase (MEK), suggesting that the action of chylomicron remnants on Egr-1 was dependent on the ERK/MEK pathway. Chylomicron remnants also induced mRNA expression of the pro-inflammatory cytokines, IL-2 and IFN-gamma in VSMCs. We conclude that chylomicron remnants act as atherogenic lipoproteins via induction of Egr-1 expression and via cytokine-mediated inflammation.

Interleukin-6 Polymorphism: A Genetic Risk Factor for Cardiac Transplant Related Coronary Vasculopathy?

AIMS

Interleukin- (IL-) 6 is a pleiotropic cytokine with effects on the acute phase response, inflammation, and vascular function. A G to C polymorphism has been described at position -174 in the promoter region of the IL-6 gene. We investigated the influence of this polymorphism on the development of cardiac transplant related coronary vasculopathy (CV).

METHODS

Sequence specific polymerase chain reaction identified the -174*G/C allele for 116 cardiac transplant recipients. Coronary disease was identified by routine surveillance post-transplant coronary angiography.

RESULTS

Prevalence of the -174*G/C polymorphism was different between the transplant and control cohorts; *CC 27.6%, *CG 45.7%, and *GG 26.7% vs. 13.2%, 44.1% and 42.7% respectively (p = 0.004). Median time to the first diagnosis of CV was different between the 3 alleles; *CC 2.8 years (2.0-4.0); *CG 3.9 years (2.1-4.5); *GG 5.3 years (3.2-6.1) (p = 0.05). By Kaplan-Meier survival analysis C homozygotes developed CV significantly earlier than the other cohorts (p = 0.035). At 5 years 100% of C homozygotes had evidence for CV. G homozygotes had a more gradual onset of CV with an approximate 60% prevalence at 5 years. *CC genotype was the most predictive risk factor for CV development (Hazard ratio 4.2 (95% CI 1.3-12.9); p = 0.014). Increasing donor age was also significant (Hazard ratio 1.04 (95% CI, 1.0-1.08); p = 0.023).

CONCLUSIONS

Polymorphism at position -174 within the promoter region of the IL-6 gene may be an important risk factor for cardiac transplant related coronary vasculopathy. This may improve patient selection and allow tailored immunosuppressive treatment.

Circulating levels of proinflammatory cytokines and neutrophil-platelet aggregates in patients with coronary artery disease

Several lines of evidence indicate that increased inflammatory activity in peripheral blood is associated with the acute coronary syndrome. Systemic inflammation in clinically stable conditions of coronary artery disease has been less studied. We examined cytokine profiles in 20 patients who had acute coronary syndrome, 45 who had angiographically verified coronary artery disease and stable angina pectoris, and 45 healthy controls. Circulating levels of C-reactive protein, interleukin-1 receptor antagonist, interleukin-2 receptor, interleukin-6, interleukin-10, and interleukin-18 were determined. Subpopulations of peripheral immune cells, including neutrophil-platelet aggregates, were analyzed by 3-color flow cytometry using a panel of monoclonal antibodies. Patients who had acute coronary syndrome and stable angina pectoris had significantly higher levels of C-reactive protein, interleukin-6, and interleukin-1 receptor antagonist than did controls, whereas levels of interleukin-2 receptor, interleukin-10, and interleukin-18 were similar across groups. Patients had significantly more neutrophils, and the numbers of neutrophil-platelet aggregates were particularly large in patients who had stable angina pectoris. High levels of C-reactive protein, interleukin-6, and interleukin-1 receptor antagonist in patients were significantly related to numbers of neutrophils and neutrophil-platelet aggregates but not to other immune cell subpopulations. The data suggest that the interaction between neutrophils and platelets is an important component of proinflammatory activity seen in peripheral blood of stable and unstable forms of coronary artery disease.

Anti-inflammatory cytokine profile in acute coronary syndromes: behavior of interleukin-10 in association with serum metalloproteinases and proinflammatory cytokines

BACKGROUND

The anti-inflammatory cytokine interleukin-10 (IL-10) downregulates the production of metalloproteinases (MMPs) and upregulates the production of their tissue inhibitors (TIMPs). The aim of this study was to assess the levels of IL-10 in patients with acute myocardial infarction (AMI) and unstable angina (UA), as well as to investigate the relationship of circulating IL-10 with the levels of MMPs (MMP-1, -2, -9), their tissue inhibitor (TIMP-1), pro-inflammatory cytokines (IL-6, tumor necrosis factor (TNF)-alpha) and serum lipids in the same patient population.

METHODS

Serum MMP-1, -2, -9, TIMP-1, IL-6, TNF-alpha and IL-10 were measured by ELISA assays in 23 patients with AMI and 20 patients with UA after their hospital admission, as well as in 16 healthy controls subjects. The lipid profile was assessed by measuring the serum levels of total cholesterol, HDL-cholesterol, LDL-cholesterol and triglycerides.

RESULTS

AMI patients exhibited significantly higher serum levels of IL-10 as compared with those of UA patients and healthy controls (both P=0.005). In contrast, there was no significant difference in IL-10 levels between UA patients and healthy controls. In AMI patients there was a statistically significant positive correlation of serum IL-10 with the levels of MMP-9 (rho=0.588, P=0.003), IL-6 (rho=0.502, P=0.015) and HDL-cholesterol (rho=0.697, P<0.001), as well as a significant negative correlation with the levels of triglycerides (rho=-0.417, P=0.048).

CONCLUSIONS

Our results suggest that UA is associated with low serum activity of IL-10, while a significant elevation of this anti-inflammatory cytokine accompanies the peripheral immune responses of AMI. This observation indicates that different patterns of inflammatory reactions are implicated in the pathophysiology of two clinical conditions.

Cigarette smoking and inflammatory indices in coronary artery disease

BACKGROUND

Smoking-induced endothelial dysfunction may lead to inflammatory activation within a vascular wall mediated by cytokines and adhesion molecules. The aim of the study was to assess the relationship between the smoking status and serum levels of tumor necrosis factor (TNF) alpha, sTNFR 1 and 2 (soluble forms of TNF receptor), Interleukin (IL)-2, IL-10 and some selected adhesion molecules (AM): sE-selectin, sP-selectin, Vascular Cell AM-1 (sVCAM-1) and Intercellular AM-1 (sICAM-1) in patients with coronary artery disease (CAD).

METHODS AND RESULTS

The study group consisted of 122 consecutive admissions with stable CAD (class II/III CCS): 31 current smokers (group I; mean age+/-S.E.M.: 53.8+/-1.6 years), 38 ex-smokers (group II; mean age+/-S.E.M.: 57.8+/-1.4 years) and 53 patients who have never smoked (group III; mean age+/-S.E.M.: 62.4+/-1.1 years). Serum concentration of IL-2 was higher in the group of active smokers (77.5+/-12.7 pg/ml) than in ex-smokers (40.0+/-10.6 pg/ml; P=0.017). AM determination also revealed differences between groups I and II-elevated serum sP-selectin levels in active smokers (174.7+/-17.1 ng/ml) than in ex-smokers (123.5+/-10.3 ng/ml; P=0.024). Serum sTNFR 2 level was higher in group III (2457.3+/-120.5 pg/ml) in comparison to group II (2018.4+/-121.5 pg/ml; P=0.006). There were no differences between TNF alpha, sTNFR 1, IL-10, sE-selectin, sICAM-1, sVCAM-1 levels in the groups examined.

CONCLUSIONS

Cigarette smoking is associated with the elevation of IL-2 and sP-selectin serum levels in patients with stable CAD. CAD patients who have never smoked are characterized by delayed onset of angina and increased sTNFR 2 concentrations.

Expression of activation molecules in neutrophils, monocytes and lymphocytes from patients with unstable angina treated with stent implantation

Coronary angioplasty is known to mediate an inflammatory response. Recently, we have characterized the transient systemic inflammatory response after coronary stent implantation in patients with unstable angina by measuring different soluble protein markers. In the present study we have characterized the expression of various cellular activation markers in neutrophils, monocytes and lymphocytes from the same group of patients. Peripheral blood samples were taken before and 24 h, 48 h and 7 days after successful coronary stenting in 58 patients. Cell surface markers (CD11b/CD18 and CD38) were analyzed by flow cytometry to determine the activation of neutrophils, monocytes and T lymphocytes. We found that coronary angioplasty with stent implantation produces an increase in the cell surface expression of CD11b/CD18 in neutrophils and CD38 in monocytes, following a similar time-course with a peak after 24 h, returning to basal levels after 48 h and a second peak after 7 days. However, T lymphocytes were not found to be activated. These results suggest that coronary stent implantation induces a different pattern inducing soluble and cellular inflammation markers, and therefore, they should be taken into account in patients undergoing stent implantation to study clinical correlations.

Expansion of peripheral CD8+ T cells in patients with coronary artery disease: relation to cytomegalovirus infection

OBJECTIVES

The nature of the immune response in coronary artery disease (CAD) is not fully defined. One pathogen that has been linked to atherogenesis, cytomegalovirus (CMV), is known to exert strong and long-lasting effects on peripheral T cells. In the present study, we investigated the effect of prior CMV infection on the immune system in CAD patients.

SUBJECTS

Patients with stable angina and angiographically verified CAD (n=43) and clinically healthy controls (n=69) were included.

METHODS

The expression of CD57 and CD28 on peripheral CD4+ and CD8+ T cells was evaluated with three-colour flow cytometry. The findings were related to serological markers of inflammation, T-cell activation and CMV seropositivity.

RESULTS

An expansion of CD8+ T cells expressing CD57 but lacking CD28 was seen in the patient group. The numbers of CD8+ CD57+ and CD8+ CD28-T-cell subsets were independently related to CMV seropositivity (P<0.001) but also to CAD per se (P<0.05). Serum concentrations of C-reactive protein (CRP) and soluble interleukin-2 receptor (sIL-2R) were elevated in the patients but not related to CMV or CD8+ T-cell subsets.

CONCLUSION

A pronounced shift in peripheral T-cell homeostasis was observed in CAD patients. Primarily CMV infection but also CAD per se contributed to the expansion of CD8+ T-cell subsets. The T-cell changes were not related to a systemic inflammatory response but should rather be considered as markers of a chronic antigen exposure and/or immunosenescence in CAD.

Serum tumour necrosis factor-alpha, interleukin-2 and interleukin-10 activation in stable angina and acute coronary syndromes

BACKGROUND

Dynamic instability of coronary atherosclerotic plaque results in the development of both unstable angina and myocardial infarction. The aim of the study was to investigate the dynamics of serum concentrations of tumour necrosis factor (TNF)alpha, interleukin (IL)-10, and IL-2 in patients with myocardial infarction (MI) and unstable angina (UA) as compared to stable angina (SA) patients and healthy volunteers.

METHODS

A total of 189 patients with coronary artery disease (CAD) were studied: 100 patients with SA (class II/III according to CCS), 57 patients with UA (Braunwald class IIIB; determinations at 6, 24, and 48 h after chest pain), and 32 patients with MI (determinations at admission, on the 7th and 30th days after MI). Twenty healthy volunteers acted as controls.

RESULTS

Serum TNFalpha levels were elevated in all CAD groups (SA: 17.3+/-4; UA: 18.7+/-4; MI: 22.0+/-3 pg/ml; p<0.001) in comparison to the controls (8.3+/-1.4 pg/ml). However, the highest values were characteristic of MI patients, especially values obtained at admission (p<0.01 versus SA and UA). Mean serum concentrations of IL-2 were significantly higher in patients with MI and UA (89.6+/-40; 87.0+/-24 pg/ml, respectively; p<0.01) when compared to SA and the control group (58.3+/-49; and 51.5+/-39, respectively). Serum IL-10 levels were also higher in MI and UA patients. Levels of IL-2 and IL-10 measured following chest pain in unstable patients, as well as their consecutive determinations in MI patients did not show any change dynamics, that is, they were persistently elevated.

CONCLUSIONS

When compared to stable CAD and healthy subjects, acute coronary syndromes are associated with long-term increase of serum concentrations of pro- and anti-inflammatory cytokines. It seems likely that sudden CAD progression leading to acute coronary syndromes is triggered/accompanied by prolonged immune activation.

Interleukins in atherosclerosis: molecular pathways and therapeutic potential

Interleukins are considered to be key players in the chronic vascular inflammatory response that is typical of atherosclerosis. Thus, the expression of proinflammatory interleukins and their receptors has been demonstrated in atheromatous tissue, and the serum levels of several of these cytokines have been found to be positively correlated with (coronary) arterial disease and its sequelae. In vitro studies have confirmed the involvement of various interleukins in pro-atherogenic processes, such as the up-regulation of adhesion molecules on endothelial cells, the activation of macrophages, and smooth muscle cell proliferation. Furthermore, studies in mice deficient or transgenic for specific interleukins have demonstrated that, whereas some interleukins are indeed intrinsically pro-atherogenic, others may have anti-atherogenic qualities. As the roles of individual interleukins in atherosclerosis are being uncovered, novel anti-atherogenic therapies, aimed at the modulation of interleukin function, are being explored. Several approaches have produced promising results in this respect, including the transfer of anti-inflammatory interleukins and the administration of decoys and antibodies directed against proinflammatory interleukins. The chronic nature of the disease and the generally pleiotropic effects of interleukins, however, will demand high specificity of action and/or effective targeting to prevent the emergence of adverse side effects with such treatments. This may prove to be the real challenge for the development of interleukin-based anti-atherosclerotic therapies, once the mediators and their targets have been delineated.

Inflammatory imbalance between IL-10 and TNFalpha in unstable angina potential plaque stabilizing effects of IL-10

BACKGROUND

The pathogenesis of atherosclerosis and acute coronary syndromes involves inflammation and immunological mechanisms. We hypothesized that patients with unstable angina may have an imbalance between inflammatory and anti-inflammatory cytokines.

DESIGN

Plasma levels of tumour necrosis factor (TNF)alpha and interleukin (IL)-10 were analyzed in 44 patients with stable angina, 29 patients with unstable angina and 20 controls. mRNA levels of these cytokines were analyzed in peripheral blood mononuclear cells (PBMC). We also studied the in vitro effects of IL-10 in PBMC from unstable angina patients.

RESULTS

Our main findings were: (1) the angina patients and particularly those with unstable disease had significantly raised TNFalpha in comparison with the controls, both at the protein and mRNA level; (2) in contrast, the levels of IL-10 were not different in the angina patients in comparison with the healthy controls, resulting in a markedly enhanced TNFalpha:IL-10 ratio, particularly in the unstable angina patients; (3) while exogenously added IL-10 markedly inhibited the release of TNFalpha, IL-8 and tissue factor as well as impairing the gelatinolytic activity and mRNA production of matrix metalloproteinase-9, it enhanced the tissue inhibitor of this metalloproteinase (i.e. TIMP-1) in PBMC from the unstable angina patients.

CONCLUSION

Patients with unstable angina appear to have an imbalance between TNFalpha and IL-10, possibly favouring inflammatory net effects. IL-10 may have beneficial effects on mechanisms that are important in plaque rupture and thrombus formation.