Cytokines in acute coronary syndromes

Meta-analysis of the association between interleukin-17 and ischemic cardiovascular disease

BACKGROUND

Interleukin-17 (IL-17) has been hypothesized to be involved in ischemic cardiovascular disease (ICVD). However, the association of IL-17 with ICVD remained unclear. The aim of this study was to systematically analyze the available evidence regarding the association between IL-17 and ICVD.

METHODS

We searched the PubMed, Web of Science, Cochrane Library, and Embase databases up to October 2023 to identify publications on the association between IL-17 and ICVD. The merged results were analyzed using a random effects model for meta-analysis and subgroup analysis.

RESULTS

A total of 955 publications were initially identified in our search and screened; six studies were eventually included in the analysis. The average age of study participants was 60.3 ± 12.6 years and 65.5% were men. There was a high degree of heterogeneity among studies. The results showed that IL-17 level were higher in the case group than those in the control group (standardized mean difference, SMD = 1.60, 95% confidence interval (95% CI): 0.53-2.66, P = 0.003). In sensitivity analysis, the merged results showed good robustness. Additionally, subgroup analysis showed that race and ethnicity, sample size, and detection methods were significant factors influencing heterogeneity in the published studies.

CONCLUSION

Our finding revealed that increased IL-17 level contributed to the development of ICVD, suggesting IL-17 as a potential risk marker. Further research is needed to establish IL-17 as a therapeutic biomarker of ICVD.

Serum Cytokines Predict the Severity of Coronary Artery Disease Without Acute Myocardial Infarction

Introduction

Various cytokines were involved in the process of atherosclerosis, and their serum levels were correlated with coronary artery disease (CAD) to varying degrees. However, there were limited reports about the correlation between serum cytokines and the severity of coronary atherosclerotic lesion in patients with non-acute myocardial infarction (AMI). The purpose of this study was to investigate the relationship between serum cytokines and the severity of CAD, and identify the predictors of severe CAD in patients suspected to have CAD but AMI had been ruled out.

Methods

A total of 502 patients who had suspected CAD and underwent coronary angiography were enrolled. The serum levels of IL-1β, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, IL-12p70, IL-17, TNF-α, IFN-α,and IFN-γ were determined by multiplexed particle-based flow cytometric assays technology. And the severity of CAD was evaluated by Gensini score (GS).

Results

The serum levels of IL-4, IL-12p70, IL-17, and IFN-α were significantly lower in the severe CAD group (GS≥30) than those in the non-severe CAD group (GS < 30). And IL-12p70 and IL-17 were negatively correlated with the severity of CAD. Multivariate logistic regression analyses demonstrated that two serum cytokines (IL-12p70 and IL-17), one clinical protective factor (HDL-C), and two clinical risk factors (gender and diabetes) were the independent predictors of severe CAD. ROC curve analysis showed that multivariate mode combined these predictors had a good performance in predicting severe CAD.

Conclusion

The combination of serum cytokines (IL-12p70 and IL-17) and clinical risk factors (HDL-C, gender, and diabetes) may help identify patients with more severe coronary artery lesions from those with suspected CAD but not AMI, and may contribute to guiding the risk stratification for patients with chest discomfort in health care facilities without sufficient medical resources (especially cardiac catheterization resources).

Apoptosis and Mobilization of Lymphocytes to Cardiac Tissue Is Associated with Myocardial Infarction in a Reperfused Porcine Model and Infarct Size in Post-PCI Patients

ST-segment elevation myocardial infarction (STEMI) is the most severe outcome of coronary artery disease. Despite rapid reperfusion of the artery, acute irrigation of the cardiac tissue is associated with increased inflammation. While innate immune response in STEMI is well described, an in-depth characterization of adaptive immune cell dynamics and their potential role remains elusive. We performed a translational study using a controlled porcine reperfusion model of STEMI and the analysis of lymphocyte subsets in 116 STEMI patients undergoing percutaneous coronary intervention (PCI). In the animal model, a sharp drop in circulating T lymphocytes occurred within the first hours after reperfusion. Notably, increased apoptosis of circulating lymphocytes and infiltration of proinflammatory Th1 lymphocytes in the heart were observed 48 h after reperfusion. Similarly, in STEMI patients, a sharp drop in circulating T lymphocyte subsets occurred within the first 24 h post-PCI. A cardiac magnetic resonance (CMR) evaluation of these patients revealed an inverse association between 24 h circulating T lymphocyte numbers and infarction size at 1-week and 6-month post-PCI. Our translational approach revealed striking changes in the circulating and tissue-infiltrating T lymphocyte repertoire in response to ischemia-reperfusion. These findings may help in developing new diagnostic and therapeutic approaches for coronary diseases.

Acute coronary syndrome-associated depression: the salience of a sickness response analogy?

Depression emerging in conjunction with acute coronary syndrome (ACS) is thought to constitute a distinct high-risk phenotype with inflammatory determinants. This review critically examines the notion put forward in the literature that ACS-associated depression constitutes a meaningful subtype that is qualitatively different from depressive syndromes observed in psychiatric patients; and evaluates the salience of an analogy to the acute sickness response to infection or injury as an explanatory model. Specific features differentiating ACS-associated depression from other phenotypes are discussed, including differences in depression symptom profiles, timing of the depressive episode in relation to ACS, severity of the cardiac event, and associated immune activation. While an acute sickness response analogy offers a plausible conceptual framework, concrete evidence is lacking for inflammatory activity as the triggering mechanism. It is likely that ACS-associated depression encompasses several causative scenarios.

Decreased plasma endogenous soluble RAGE, and enhanced adipokine secretion, oxidative stress and platelet/coagulative activation identify non-alcoholic fatty liver disease among patients with familial combined hyperlipidemia and/or metabolic syndrome

OBJECTIVE

In patients with familial combined hyperlipidemia (FCHL), without metabolic syndrome (MS), occurrence of non-alcoholic fatty liver disease (NAFLD) is related to a specific pro-inflammatory profile, influenced by genetic traits, involved in oxidative stress and adipokine secretion. Among FCHL or MS patients, hyperactivity of the ligand-receptor for advanced glycation-end-products (RAGE) pathway, as reflected by inadequate protective response by the endogenous secretory (es)RAGE, in concert with genetic predisposition, may identify those with NAFLD even before and regardless of MS.

METHODS

We cross-sectionally compared 60 patients with vs. 50 without NAFLD. Each group included patients with FCHL alone, MS alone, and FCHL plus MS.

RESULTS

NAFLD patients had significantly lower plasma esRAGE, IL-10 and adiponectin, and higher CD40 ligand, endogenous thrombin potential and oxidized LDL. The effects of MS plus FCHL were additive. The genotypic cluster including LOX-1 IVS4-14A plus ADIPO 45GG and 256 GT/GG plus IL-10 10-1082G, together with higher esRAGE levels highly discriminate FCHL and MS patients not developing NAFLD.

CONCLUSIONS

Among FCHL or MS patients, noncarriers of the protective genotypic cluster, with lower esRAGE and higher degree of atherothrombotic abnormalities coincide with the diagnosis of NAFLD. This suggests an interplay between genotype, adipokine secretion, oxidative stress and platelet/coagulative activation, accelerating NAFLD occurrence as a proxy for cardiovascular disease.

Systemic inflammatory response following acute myocardial infarction

Acute cardiomyocyte necrosis in the infarcted heart generates damage-associated molecular patterns, activating complement and toll-like receptor/interleukin-1 signaling, and triggering an intense inflammatory response. Inflammasomes also recognize danger signals and mediate sterile inflammatory response following acute myocardial infarction (AMI). Inflammatory response serves to repair the heart, but excessive inflammation leads to adverse left ventricular remodeling and heart failure. In addition to local inflammation, profound systemic inflammation response has been documented in patients with AMI, which includes elevation of circulating inflammatory cytokines, chemokines and cell adhesion molecules, and activation of peripheral leukocytes and platelets. The excessive inflammatory response could be caused by a deregulated immune system. AMI is also associated with bone marrow activation and spleen monocytopoiesis, which sustains a continuous supply of monocytes at the site of inflammation. Accumulating evidence has shown that systemic inflammation aggravates atherosclerosis and markers for systemic inflammation are predictors of adverse clinical outcomes (such as death, recurrent myocardial infarction, and heart failure) in patients with AMI.

Neurohumoral improvement and torsional dynamics in patients with heart failure after treatment with levosimendan

Background

Levosimendan improves clinical and hemodynamic parameters exerting an anti-inflammatory and antiapoptotic effect in decompensated heart failure. The aim of this study was to evaluate the effects of levosimendan on LV torsion, plasma levels of NT-proBNP and on the balance between pro-inflammatory (TNF-α, IL-6) and anti-inflammatory cytokines (IL-10).

Methods

We enrolled 24 patients (age 62 ± 7 years) with acute HF, NYHA class IV and severe LV dysfunction. All patients underwent transthoracic echocardiography using two-dimensional speckle tracking analysis to detect LV twist angle (LVTA), at baseline and 1 week after treatment with levosimendan infusion. Biochemical parameters (pro-BNP, IL-6, IL-10, TNF-α) were determined by enzyme-linked immunosorbent (ELISA).

Results

After one week, we observed an improvement in LV function especially in LVTA (4.15 ± 2.54 vs 2.9 ± 2.1 p < 0.01), in LV ejection fraction (27.3 ± 8.04 vs 21.6 ± 6.8 p = 0.03) and also a significant reduction in BNP levels (1844 ± 560 vs 4713 ± 1050, p = 0.03). The multiple linear regression analysis showed a significant relation between a reduction of TNF α/IL-10 ratio (Δ > 20%) and BNP (Δ > 40%), LVEF (Δ > 10%) and LVTA (Δ > 20%) (O.R. 1.77, 95% C.I. 1.11–2.83; O.R. 1.49, 95% C.I. 1.08–2.67; O.R. 1.66, 95% C.I. 1.10–2.74, respectively, confirmed p, all < 0.01 by Hosmer–Lemeshov confirmation and the formal test for interaction).

Conclusions

Levosimendan exerts a hemodynamic effect by improving EF and LV torsion in patients with acute HF in association with a positive effect on the balance between pro and anti-inflammatory cytokines.

Age and stress related phenotypical changes in bone marrow CD34+ cells

OBJECTIVE

Phenotypical changes in the human bone marrow (BM) due to age and stress have not so far been properly addressed in the literature. In the present study, we compared CD34(+) BM cells between older and young volunteers. The influence of stress on CD34(+) cell phenotype in older patients was investigated in an age-matched group with acute myocardial infarction (AMI). Cytokines thought to influence BM CD34(+) cell homeostasis were also analysed.

MATERIAL AND METHODS

BM mononuclear cells of 10 older volunteers and of 7 young volunteers (18-25 years), as well as 22 AMI patients, were analysed by flow cytometry for the following markers: CD34, CD38, CD117 (c-kit) and CD133. Blood samples were analysed for CRP, IL-6, MCP-1, IL-8, MMP-9, TIMP-1 and TNFalpha by ELISA methods.

RESULTS

Significantly higher numbers of CD34(+) CD38(-) cells (both absolute and relative) were observed in older volunteers than in young volunteers and AMI patients. Higher numbers of immature progenitors, namely CD34(+)CD38(-) cells and CD34(+)CD38(-)CD117(+)CD133(+) cells, were observed among older volunteers compared to the other groups. However, the relative number of CD34(+) cells lacking CD38 expression or expressing CD133 was higher in the old volunteers and AMI patients. None of the circulating factors investigated correlated with any of the cell population yields.

CONCLUSION

In this study, we found that the absolute and relative numbers of BM CD34(+)CD38(-) progenitor cells increase with age. The increment is attenuated in patients with AMI.

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.

Cardioprotective effect by tumor necrosis factor-alpha and interleukin-6 through late preconditioning in unstable angina patients

BACKGROUND

It has recently been demonstrated that upregulation of proinflammatory cytokines plays an important role in induction of the late preconditioning in rodent models. The aim of this study was to determine if there was a late preconditioning effect caused by higher proinflammatory cytokines in unstable angina patients.

METHODS

TNFalpha and IL-6 levels in plasma before surgery were determined by an enzyme-linked immunosorbent assay. Biopsies of right atrial tissue were obtained from patients with unstable and stable coronary artery disease in conjunction with coronary artery bypass surgery. The two main transcription factors involved in the late preconditioning nuclear factor kappaB (NFkappaB), signal transducer and activator of transcription 3 (STAT3) were investigated by electromobility shift assay. The effector proteins in late preconditioning including inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2) were evaluated by immunoblotting as candidates for possible endogenous cardioprotective agents. Cardioprotective effects were assessed by creatine kinase MB (CK-MB) and cTnT leakage postoperatively.

RESULTS

We found parallel relationships between plasma cytokine levels, activated extent of transcription factors, expression quantities of effector proteins, and cardioprotective effects assessed by CK-MB and cTnT.

CONCLUSIONS

Upregulation of the proinflammatory cytokines in plasma by unstable angina induces late preconditioning effects and shifts the myocardium to a preconditioned phenotype upon exposure to impending stress.

Pro-inflammatory cytokines may induce late preconditioning in unstable angina patients

Late preconditioning can be induced by a wide variety of stimulus, including non-pharmacological and pharmacological. Thus, late preconditioning is a universal response of the heart to stress and it requires the simultaneous activation of multiple stress-responsive genes. Recently, compelling evidence has evolved that the up-regulation of pro-inflammatory cytokines plays an important role in induction of the late phase of ischemic preconditioning in rodent models. However, the role of cytokines in induction of late preconditioning in humans has not been explored. Patients with unstable coronary syndromes have a systemic inflammatory responses with increase of the pro-inflammatory cytokines, such as TNFalpha, IL-6. And some researchers find the patients undergoing CABG with unstable angina have a better cardioprotective effect caused by late preconditioning characterized by the activated NF-kappaB and synthesized effector proteins (HSP72 and eNOS). Therefore, we hypothesize that pro-inflammatory cytokines may induce late preconditioning in unstable angina patients directly or through remote preconditioning. It is difficult to test our hypotheses in vivo, but in vitro, human tissue culture with isolated atrial myocardium could be tested. If the hypotheses is true, the biological complication is immense. A new physiological function of pro-inflammatory cytokines is found, that is, inducing endogenous cytoprotection. From the clinical point of view, administering the appropriate pro-inflammatory cytokines will be beneficial to patients before cardiac surgery.