Monocyte Subsets and Inflammatory Cytokines in Acute Decompensated Heart Failure

Corticosteroid burst therapy in patients with acute heart failure: Design of the CORTAHF pilot study

AIMS

Inflammation has emerged as a potential key pathophysiological mechanism in heart failure (HF) in general and acute HF (AHF) specifically, with inflammatory biomarkers shown to be highly predictive of adverse outcomes in these patients. The CORTAHF study builds on both these data and the fact that steroid burst therapy has been shown to be effective in the treatment of respiratory diseases and COVID-19. Our hypothesis is that in patients with AHF and elevated C-reactive protein (CRP) levels without symptoms or signs of infection, a 7-day course of steroid therapy will lead to reduced inflammation and short-term improvement in quality of life and a reduced risk of worsening HF (WHF) events.

METHODS AND RESULTS

The study, which is currently ongoing, will include 100 patients with AHF ages 18-85, regardless of ejection fraction, screened within 12 h of presentation. Patients will be included who have NT-proBNP > 1500 pg/mL and CRP > 20 mg/L at screening. Exclusion criteria include haemodynamic instability and symptoms and signs of infection. After signed consent, eligible patients will be randomized according to a central randomization scheme stratified by centre 1:1 to either treatment once daily for 7 days with 40 mg prednisone orally or to standard care. Patients will be assessed at study day 2, day 4 or at discharge if earlier, and at days 7 and 31 at the hospital; and at day 91 through a telephone follow-up. The primary endpoint is the change in CRP level from baseline to day 7, estimated from a mixed model for repeated measures (MMRM) including all measured timepoints, in patients without a major protocol violation. Secondary endpoints include the time to the first event of WHF adverse event, readmission for HF, or death through day 91; and changes to day 7 in EQ-5D visual analogue scale score and utility index. Additional clinical and laboratory measures will be assessed.

CONCLUSIONS

The results of the study will add to the knowledge of the role of inflammation in AHF and potentially inform the design of larger studies with possibly longer duration of anti-inflammatory therapies in AHF.

Exploring the causal relationship between immune cell and all-cause heart failure: a Mendelian randomization study

Background and objectives

Heart failure (HF) is a disease with numerous genetic and environmental factors that affect it. The results of previous studies indicated that immune phenotypes are associated with HF, but there have been inconclusive studies regarding a causal relationship. Therefore, Mendelian randomization (MR) analyses were undertaken to confirm the causal connections between immune phenotypes and HF, providing genetic evidence supporting the association of immune cell factors with HF risk.

Methods

We selected instrumental variables that met the criteria based on data from the results of genome-wide association studies (GWAS) of immune phenotype and all-cause HF. An evaluation of the causal association between 731 immune cell factors and HF risk was carried out using the inverse variance weighted (IVW), MR-Egger regression (MR-Egger), and weighted median (WM) analysis methods. To determine the horizontal pleiotropy, heterogeneity, and stability of the genetic variants, the MR-Egger intercept test, Cochran's Q test, MR-PRESSO, and leave-one-out sensitivity analysis were performed.

Results

MR principal method (IVW) analysis showed that a total of 38 immune cell-related factors were significantly causally associated with HF. Further analyses combining three methods (IVW, MR-Egger and WME) showed that six exposure factors significantly associated with heart failure, as shown below. The effect of Dendritic cell Absolute Count, CD62l- CD86+ myeloid Dendritic cell Absolute Count, CD62l- CD86+ myeloid Dendritic cell% Dendritic cell, CD39+ CD8+ T cell% CD8+ T cell, CD3 on Central Memory CD4+ T cell on heart failure was positive. Whereas, a reverse effect was observed for CD14+ CD16+ monocyte% monocyte.

Conclusion

We investigated the causal relationship between immune phenotypes and all-cause HF. According to the results, Dendritic cell Absolute Count, CD62l- CD86+ myeloid Dendritic cell Absolute Count, CD62l- CD86+ myeloid Dendritic cell% Dendritic cell, CD39+ CD8+ T cell% CD8+ T cell, CD3 on Central Memory CD4+ T cell aggravate HF, and the risk of HF is decreased by CD14+ CD16+ monocyte% monocyte. These phenotypes may serve as new biomarkers, providing new therapeutic insights for the prevention and treatment of all-cause HF.

The Emerging Field of Cardioimmunology: Past, Present and Foreseeable Future

Over the past 30 years, the field of cardioimmunology has moved from being dismissed as a field that was chasing an epiphenomenon of little biological consequence to a scientific discipline that is providing important new insights into the immunologic basis for hypertension, atherosclerosis, myocarditis, pericarditis, autoimmune heart disease, and heart failure. In this article, we will review the conceptual insights and technical breakthroughs that have allowed the field to move forward, as well as the clinical trials in the cardioimmunology space, to provide a historical context for the articles that will appear in the compendium that is focused on the interface between cardioimmunology, myocardial function, and disease.

Glycocalyx Disruption Triggers Human Monocyte Activation in Acute Heart Failure Syndromes

PURPOSE

Acute heart failure (AHF) syndromes manifest increased inflammation and vascular dysfunction; however, mechanisms that integrate the two in AHF remain largely unknown. The glycocalyx (GAC) is a sugar-based shell that envelops all mammalian cells. Much GAC research has focused on its role in vascular responses, with comparatively little known about how the GAC regulates immune cell function.

METHODS

In this study, we sought to determine if GAC degradation products are elevated in AHF patients, how these degradation products relate to circulating inflammatory mediators, and whether the monocyte GAC (mGAC) itself modulates monocyte activation. Inflammatory markers and GAC degradation products were profiled using ELISAs. Flow cytometry was used to assess the mGAC and RNA-seq was employed to understand the role of the mGAC in regulating inflammatory activation programs.

RESULTS

In a cohort of hospitalized AHF patients (n = 17), we found that (1) the GAC degradation product heparan sulfate (HS) was elevated compared with age-matched controls (4396 and 2903 ng/mL; p = 0.01) and that (2) HS and soluble CD14 (a marker of monocyte activation) levels were closely related (Pearson's r = 0.65; p = 0.002). Mechanistically, Toll-like receptor (TLR) activation of human monocytes results in GAC remodeling and a decrease in the mGAC (71% compared with no treatment; p = 0.0007). Additionally, we found that ex vivo enzymatic removal of HS and disruption of the mGAC triggers human monocyte activation and amplifies monocyte inflammatory responses. Specifically, using RNA-seq, we found that enzymatic degradation of the mGAC increases transcription of inflammatory (IL6, CCL3) and vascular (tissue factor/F3) mediators.

CONCLUSION

These studies indicate that the mGAC is dynamically remodeled during monocyte activation and that mGAC remodeling itself may contribute to the heightened inflammation associated with AHF.

Short-Term Prognostic Efficacy of mGPS and LCS in Patients With Acute Heart Failure

Aim

Systemic inflammation plays an important role in the occurrence and development of acute heart failure. The modified Glasgow Prognostic Score (mGPS) and “lymphocyte C-reactive protein score” (LCS) are used to assess the inflammation levels in cancer patients. The purpose of this study was to assess the prognostic value of these two inflammation-related scoring systems in patients with acute heart failure.

Methods

Two hundred and fifty patients with acute heart failure were enrolled in this study. The mGPS and LCS scores were recorded after admission. All patients were divided into 2 groups: the death group and the survival group according to the 3-month follow-up results. The predictive values of mGPS and LCS were assessed using receiver-operating characteristic (ROC) analyses. Univariate and multivariate logistic analyses were used to evaluate the relationships between variables and endpoint.

Results

The levels of mGPS and LCS in the death group were significantly higher than those in the survival group (P < 0.05). The areas under the ROC curve of the mGPS and LCS for predicting death were 0.695 (95%CI: 0.567~0.823) and 0.736 (95%CI: 0.616~0.856), respectively. Multivariate analysis demonstrated that both LCS, LVEF and serum direct bilirubin were independent predictors of all-cause death, excluding mGPS.

Conclusions

Compared with mGPS, LCS is independently associated with short-term outcomes in patients with acute heart failure. LCS was a clinically promising and feasible prognostic scoring system for patients with acute heart failure.

Effect of systemic corticosteroid therapy for acute heart failure patients with elevated C-reactive protein

AIMS

The current study explores whether degree of inflammation, reflected by C-reactive protein (CRP) level, modifies the effect of intravenous (IV) corticosteroid administered in the emergency department (ED) on clinical outcomes in patients with acute heart failure (AHF).

METHODS AND RESULTS

We selected patients diagnosed with AHF in the ED, with confirmed N-terminal pro-B-type natriuretic peptide > 300 pg/mL and CRP > 5 mg/L in the ED from the Epidemiology of Acute Heart Failure in the Emergency Departments (EAHFE) registry. In these 1109 patients, 121 were treated by corticosteroid. The corticosteroid therapy hazard ratio (HR) for 30 day all-cause mortality was 1.26 [95% confidence interval (CI) 0.75-2.09, P = 0.38]. Although not statistically significant, HRs tended to decrease with increasing CRP level, with point estimates favouring corticosteroid at CRP levels above 20. In patients with CRP > 40 mg/L, with adjusted HRs of 0.56 (95% CI 0.20-1.55, P = 0.27) for 30 day all-cause mortality, 0.92 (95% CI 0.52-1.62, P = 0.78) for 30 day post-discharge ED revisit, hospitalization, or death, and adjusted odds ratio of 0.61 (95% CI 0.17-2.14, P = 0.44) for in-hospital all-cause mortality.

CONCLUSIONS

The present analysis suggests that corticosteroids might have the potential to improve outcomes in AHF patients with inflammatory activation. Larger, prospective studies of anti-inflammatory therapy should be considered to assess potential benefit in patients with the highest degree of inflammation.

Mechanism of Zhen Wu Decoction in the Treatment of Heart Failure Based on Network Pharmacology and Molecular Docking

Heart failure (HF) is a serious manifestation or advanced stage of various cardiovascular diseases, and its mortality and rehospitalization rate are still on the rise in China. Based on the network pharmacology method, 59 components of Zhen Wu decoction (ZWD) and 83 target genes related to HF were obtained. Through the PPI network, four potential therapeutic targets were identified: AKT1, IL6, JUN, and MAPK8. The beneficial components of ZWD might intervene HF through the AGE-RAGE signalling pathway in the diabetes component, fluid shear stress and atherosclerosis, the TNF signalling pathway, TB, and Kaposi sarcoma related herpesvirus infection, according to a KEGG enrichment study. The protein interaction network of candidate targets was constructed by the STRING database, and the protein interaction network was clustered by MEODE software. GO and KEGG enrichment analyses were performed on the core modules obtained by clustering. Finally, AutoDock Vina software was used for molecular docking verification of key targets and active ingredients. The result was that 75 active ingredients and 109 genes were screened as potential active ingredients and potential targets of Shengjie Tongyu decoction for CHF treatment. The main active components were quercetin, luteolin, kaempferol, dehydrated icariin, isorhamnetin, formononetin, and other flavonoids. Il-6, MAPK1, MAPK8, AKT1, VEGFA, and JUN were selected as the core targets. Molecular docking showed that the key components were well connected with the target. GO enrichment analysis showed that Shengjie Tongyu decoction could play a role through multiple biological pathways including angiogenesis, regulation of endothelial cell proliferation, binding of cytokine receptors, negative regulation of apoptotic signalling pathways, regulation of nitric oxide synthase activity, and reactive oxygen metabolism. Key pathways mainly focus on the toll-like receptor signalling pathway, nod-like receptor signalling pathway, MAPK signalling pathway, mTOR signalling pathway, JAK-STAT signalling pathway, VEGF signalling pathway, and other pathways. Through molecular docking technology, it was found that a variety of effective components in ZWD, such as kaempferol. Molecular docking technology has preliminatively verified the network pharmacology and laid a foundation for the follow-up pharmacological research.

A New Biomarker Tool for Risk Stratification in “de novo” Acute Heart Failure (OROME)

Background: Inflammation is one of the mechanisms involved in heart failure (HF) pathophysiology. Thus, the acute phase reactant protein, orosomucoid, was associated with a worse post-discharge prognosis in de novo acute HF (AHF). However, the presence of anti-inflammatory adipokine, omentin, might protect and reduce the severity of the disease. We wanted to evaluate the value of omentin and orosomucoid combination for stratifying the risk of these patients.

Methods and Results: Two independent cohorts of patients admitted for de novo AHF in two centers were included in the study (n = 218). Orosomucoid and omentin circulating levels were determined by ELISA at discharge. Patients were followed-up for 317 (3–575) days. A predictive model was determined for the primary endpoint, death, and/or HF readmission. Differences in survival were evaluated using a Log-rank test. According to cut-off values of orosomucoid and omentin, patients were classified as UpDown (high orosomucoid and low omentin levels), equal (both proteins high or low), and DownUp (low orosomucoid and high omentin levels). The Kaplan Meier determined a worse prognosis for the UpDown group (Long-rank test p = 0.02). The predictive model that includes the combination of orosomucoid and omentin groups (OROME) + NT-proBNP values achieved a higher C-index = 0.84 than the predictive model with NT-proBNP (C-index = 0.80) or OROME (C-index = 0.79) or orosomucoid alone (C-index = 0.80).

Conclusion: The orosomucoid and omentin determination stratifies de novo AHF patients into the high, mild, and low risk of rehospitalization and/or death for HF. Its combination with NT-proBNP improves its predictive value in this group of patients.

[Patterns of immunological reactions in the pathogenesis of chronic heart failure: review]

The immune system is essential for maintaining the homeostasis. At present, there is convincing evidence for participation of the immune system in the pathogenesis of cardiovascular pathology, including the final step of cardiovascular continuum, heart failure. Objective difficulties in understanding subtle processes of loss of the normal cardiac structure and function are based on the diversity of pathogenetic factors of development and progression of chronic heart failure (CHF) and the involvement of most organs and body systems. Russian and international scientists actively study issues of immune homeostasis, including the efficacy of current immune therapy. At the same time, available reports are largely uncompiled and reflect isolated parts of the immunopathogenesis of cardiovascular diseases. This review focuses on comprehensive elucidation of major patterns of immune processes in the CHF pathogenesis to form an integral view of the problem under study.

Monocyte Subsets in Patients with Chronic Heart Failure Treated with Cardiac Resynchronization Therapy

Background: The exact role of individual inflammatory factor in heart failure with reduced ejection fraction (HFrEF) remains elusive. The study aimed to evaluate three monocyte subsets (classical-CD14⁺⁺CD16⁻, intermediate-CD14⁺⁺CD16⁺, and nonclassical-CD14⁺CD16⁺⁺) in HFrEF patients and to assess the effect of the cardiac resynchronization therapy (CRT) on the changes in monocyte compartment. Methods: The study included 85 patients with stable HFrEF. Twenty-five of them underwent CRT device implantation with subsequent 6-month assessment. The control group consisted of 23 volunteers without HFrEF. Results: The analysis revealed that frequencies of non-classical-CD14⁺CD16⁺⁺ monocytes were lower in HFrEF patients compared to the control group (6.98 IQR: 4.95–8.65 vs. 8.37 IQR: 6.47–9.94; p = 0.021), while CD14⁺⁺CD16⁺ and CD14⁺⁺CD16⁻ did not differ. The analysis effect of CRT on the frequency of analysed monocyte subsets 6 months after CRT device implantation showed a significant increase in CD14⁺CD16⁺⁺ (from 7 IQR: 4.5–8.4 to 7.9 IQR: 6.5–9.5; p = 0.042) and CD14⁺⁺CD16⁺ (from 5.1 IQR: 3.7–6.5 to 6.8 IQR: 5.4–7.4; p = 0.017) monocytes, while the frequency of steady-state CD14⁺⁺CD16⁻ monocytes was decreased (from 81.4 IQR: 78–86.2 to 78.2 IQR: 76.1–81.7; p = 0.003). Conclusions: HFrEF patients present altered monocyte composition. CRT-related changes in the monocyte compartment achieve levels observed in controls without HFrEF.

The Association Between Monocyte Subsets and Cardiometabolic Disorders/Cardiovascular Disease: A Systematic Review and Meta-Analysis

Background: Monocyte subsets in humans, i.e., classical (CM), intermediate (IM), and non-classical monocytes (NCM), are thought to differentially contribute to the pathogenesis of atherosclerosis, the leading cause of cardiovascular disease (CVD). However, the association between monocyte subsets and cardiometabolic disorders and CVD is not well-understood. Thus, the aim of the current systematic review and meta-analysis was to evaluate recent findings from clinical studies that examined the association between the distribution of monocyte subsets in subjects with cardiometabolic disorders and CVD compared to healthy controls.

Methods: Articles were systematically searched in CINAHL, PubMed and Cochrane Library. Articles were independently screened and selected by two reviewers. Studies that reported the percentage of each monocyte subset were included in the systematic review and meta-analysis. For the meta-analysis, a random-effects model was used to generate pooled standardized mean differences (SMD) between subjects with cardiometabolic disorders and healthy controls.

Results: A total of 1,693 articles were screened and 27 studies were selected for qualitative analyses. Among them, six studies were included in the meta-analysis. In total, sample size ranged from 22 to 135 and mean or median age from 22 to 70 years old. We found studies that reported higher percentage and number of IM and/or NCM in subjects with cardiometabolic disorders (9 out of 13 studies) and in subjects with CVD (11 out of 15 studies) compared to healthy controls. In the meta-analysis, the percentage of CM was lower [SMD = −1.21; 95% CI (−1.92, −0.50); P = 0.0009; I² = 91%] and the percentage of IM [SMD = 0.56; 95% CI (0.23, 0.88); P = 0.0008; I² = 65%] and NCM [SMD = 1.39; 95% CI (0.59, 2.19); P = 0.0007; I² = 93%] were higher in subjects with cardiometabolic disorders compared to healthy controls.

Conclusions: Individuals with cardiometabolic disorders and CVD may have a higher percentage of IM and NCM than healthy controls. Future studies are needed to evaluate the cause and biological significance of this potential altered distribution of monocyte subsets.

The Additive Prognostic Value of Serial Plasma Interleukin-6 Levels over Changes in Brain Natriuretic Peptide in Patients with Acute Heart Failure

BACKGROUND

Elevated plasma interleukin-6 (IL-6) concentrations are frequently observed in patients with acute heart failure (AHF). However, the predictive value of serial IL-6 measurements beyond brain natriuretic peptide (BNP) remains poorly characterized.

METHODS AND RESULTS

This was a retrospective analysis of the PROTECT cohort (2033 patients with AHF). Plasma IL-6 and BNP levels were determined on days 1, 2, 7 and 14 after admission for AHF in 1591 (78.3%), 1462 (71.9%), 1445 (71.1%) and 1451 (71.4%) patients, respectively. The primary endpoint was 180-day all-cause mortality. The median day-1 IL-6 concentration was 11.1 pg/mL (IQR: 6.6, 20.9) and decreased to 10.1 pg/mL (IQR: 5.6-18.5) at day-7. Higher cross-sectional IL-6 concentrations at all time-points predicted the primary endpoint, independent of a risk model for this cohort and changes in BNP. Each doubling of IL-6 between day-1 and day-7 predicted the primary endpoint independent of baseline IL-6 concentrations, the risk model, baseline BNP and changes in BNP [HR (95% CI): 1.18 (1.07-1.30), p=0.0013]. Collectively, 214 (17%) patients experienced at least a doubling of their IL-6 concentrations between day-1 and day-7.

CONCLUSIONS

We demonstrate that the temporal evolution patterns of IL-6 in patients with AHF have additive prognostic value independent of changes in BNP.

Leucocyte count predicts cardiovascular risk in heart failure with preserved ejection fraction: insights from TOPCAT Americas

AIMS

Prior evidence has implicated leucocyte expansion in several cardiovascular disorders, including heart failure (HF) with reduced ejection fraction (rEF). However, the prognostic importance of leucocyte count in HF with preserved EF (HFpEF) remains largely unexplored.

METHODS AND RESULTS

The Americas cohort of the treatment of preserved cardiac function heart failure with an aldosterone antagonist (TOPCAT-Americas) was used to evaluate the association between total leucocyte count and clinical outcomes in HFpEF. The primary outcome was a composite of aborted cardiac arrest, cardiovascular mortality, or hospitalization for HF. Secondary outcomes were hospitalization for HF, aborted cardiac arrest, stroke, non-fatal myocardial infarction (MI), cardiovascular mortality, non-cardiovascular mortality, and all-cause mortality. Survival models were used to identify the risk of the primary and secondary outcomes in those with leucocyte count above the median (7100 cells/μL), as compared to those with leucocyte count below the median, during the follow-up period. A total of 1746 (out of 1767; 99%) patients from TOPCAT-Americas were available for the analyses with a median follow up of 2.4 (25th to 75th percentile 1.4-3.9) years. Patients with leucocyte count >7100 cells/μL were 36% more likely to experience the primary endpoint compared to those with ≤7100 cells/μL (hazard ratio: 1.36, 95% confidence interval: 1.14-1.61). This association remained significant after extensive adjustment for potential confounders (hazard ratio: 1.27, 95% confidence interval: 1.06-1.52). We also observed a greater incidence of HF hospitalization and non-fatal MI in patients with higher leucocyte count. These associations remained robust on sensitivity analyses, suggesting a low probability of confounding. Exploratory analyses suggested that both higher leucocyte count (integrating the combined influence of both myeloid and lymphoid immune cells) and augmented platelet count (as a surrogate for myeloid immune cell expansion) in the same model were associated with the primary outcome (both P < 0.05).

CONCLUSIONS

Leucocyte count >7100 cells/μL was independently associated with adverse clinical outcomes in HFpEF patients from TOPCAT-Americas. These results were primarily driven by the HF hospitalization outcome but were also accompanied by an excess of non-fatal MI. Further research is needed to define the mechanisms underlying our findings and their prognostic implications.

Single-cell RNA-sequencing reveals profound changes in circulating immune cells in patients with heart failure

AIMS

Identification of signatures of immune cells at single-cell level may provide novel insights into changes of immune-related disorders. Therefore, we used single-cell RNA-sequencing to determine the impact of heart failure on circulating immune cells.

METHODS AND RESULTS

We demonstrate a significant change in monocyte to T-cell ratio in patients with heart failure, compared to healthy subjects, which were validated by flow cytometry analysis. Subclustering of monocytes and stratification of the clusters according to relative CD14 and FCGR3A (CD16) expression allowed annotation of classical, intermediate, and non-classical monocytes. Heart failure had a specific impact on the gene expression patterns in these subpopulations. Metabolically active genes such as FABP5 were highly enriched in classical monocytes of heart failure patients, whereas β-catenin expression was significantly higher in intermediate monocytes. The selective regulation of signatures in the monocyte subpopulations was validated by classical and multifactor dimensionality reduction flow cytometry analyses.

CONCLUSION

Together this study shows that circulating cells derived from patients with heart failure have altered phenotypes. These data provide a rich source for identification of signatures of immune cells in heart failure compared to healthy subjects. The observed increase in FABP5 and signatures of Wnt signalling may contribute to enhanced monocyte activation.

Reappraising the role of inflammation in heart failure

The observation that heart failure with reduced ejection fraction is associated with elevated circulating levels of pro-inflammatory cytokines opened a new area of research that has revealed a potentially important role for the immune system in the pathogenesis of heart failure. However, until the publication in 2019 of the CANTOS trial findings on heart failure outcomes, all attempts to target inflammation in the heart failure setting in phase III clinical trials resulted in neutral effects or worsening of clinical outcomes. This lack of positive results in turn prompted questions on whether inflammation is a cause or consequence of heart failure. This Review summarizes the latest developments in our understanding of the role of the innate and adaptive immune systems in the pathogenesis of heart failure, and highlights the results of phase III clinical trials of therapies targeting inflammatory processes in the heart failure setting, such as anti-inflammatory and immunomodulatory strategies. The most recent of these studies, the CANTOS trial, raises the exciting possibility that, in the foreseeable future, we might be able to identify those patients with heart failure who have a cardio-inflammatory phenotype and will thus benefit from therapies targeting inflammation.

CRP genetic variants are associated with mortality and depressive symptoms in chronic heart failure patients

OBJECTIVE

Heart failure (HF) is a complex medical condition with a multitude of genetic and other factors being involved in the pathogenesis. Emerging evidence points to an involvement of inflammatory mechanisms at least in subgroups of patients. The same is true for depression and depressive symptoms, which have a high prevalence in HF patients and are risk factors for the development and outcomes of cardiovascular disease.

METHODS

In 936 patients of the Interdisciplinary Network Heart Failure (INH) program, CRP and IL-6 protein blood levels were measured and genetic variants (single nucleotide polymorphisms) of the CRP and IL6 gene analyzed regarding their influence on mortality.

RESULTS

Less common recessive genotypes of two single nucleotide polymorphisms in the CRP gene (rs1800947 and rs11265263) were associated with significantly higher mortality risk (p < 0.006), higher CRP levels (p = 0.029, p = 0.006) and increased depressive symptoms in the PHQ-9 (p = 0.005, p = 0.003). Variants in the IL-6 gene were not associated with mortality.

CONCLUSION

Our results hint towards an association of less common CRP genetic variants with increased mortality risk, depressive symptoms and peripheral CRP levels in this population of HF patients thereby suggesting a possible role of the inflammatory system as link between poor prognosis in HF and depressive symptoms.

Expression of CD206 and CD163 on intermediate CD14++CD16+ monocytes are increased in hemorrhagic fever with renal syndrome and are correlated with disease severity

BACKGROUND

Hantaan virus infection causes lethal hemorrhagic fever with renal syndrome (HFRS) in humans. Little is known about how monocytes contribute to HFRS pathogenesis. In this study, we aimed to investigate changes in various monocyte subsets in HFRS patients.

METHODS

A total of 41 HFRS patients and 17 age-, sex-, and ethnicity-matched healthy control subjects were included in this study. Numbers/percentages of various monocyte subsets were quantitatively determined using flow cytometry. Serum levels of interleukin (IL)-10, IL-12, and tumor necrosis factor alpha (TNF-α) were detected using a cytometric bead array (CBA).

RESULTS

CD14⁺⁺CD16⁺ intermediate monocytes were significantly higher in HFRS patients compared to healthy controls (P < 0.01), especially during the acute phase. The expression of both CD163 and CD206 on CD14⁺⁺CD16⁺ intermediate monocytes were increased during the acute phase of HFRS (P < 0.01 and P < 0.05, respectively) when comparing the convalescent phase and healthy controls. Furthermore, the numbers of CD14⁺⁺CD16⁺ monocytes during the acute phase, and the percentages of CD14⁺⁺CD16⁺CD163⁺ monocytes in patients with severe/critical HFRS were much higher compared to patients with mild/moderate HFRS. This also positively correlated with increased levels of white blood cells (WBC), blood urea nitrogen (BUN), and creatinine (Cr). However, the percentages of CD14⁺⁺CD16⁺CD206⁺monocytes were higher in mild/moderate HFRS than in severe/critical HFRS, and they negatively correlated with platelets (PLT) and Cr.

CONCLUSIONS

Higher frequency of the CD14⁺⁺CD16⁺ intermediate monocytes and increased expression of CD163⁺ and CD206⁺ markers on CD14⁺⁺CD16⁺ monocytes were detected in patients with HFRS. The changes in the frequency of CD14⁺⁺CD16⁺ monocytes and expression of CD163 and CD206 markers on CD14⁺⁺CD16⁺ monocytes positively correlated with the severity of HFRS.

Natriuretic peptides system in the pulmonary tissue of rats with heart failure: potential involvement in lung edema and inflammation

Congestive heart failure (CHF) often leads to progressive cardiac hypertrophy and salt/water retention as evident by peripheral and lung edema. Although the pathogenesis of CHF remains largely unclarified, it is widely accepted that neurohormonal changes and inflammatory processes are profoundly involved in structural and functional deterioration of vital organs including, heart, kidney and lungs. Corin, a cardiac serine protease, is responsible for converting pro-ANP and pro-BNP to biologically active natriuretic peptides (NPs). Although the involvement of corin in cardiac hypertrophy and heart failure was extensively studied, the alterations in corin and PCSK6, a key enzyme in the conversion of procorin to corin, have not been studied in the pulmonary tissue. Thus, this study aims at examining the status of PCSK6/Corin in the lung of rats with CHF induced by the creation of aorto-caval fistula (ACF) between the abdominal aorta and vena cava in SD rats. Rats with ACF were divided into 2 subgroups based on the pattern of their daily sodium excretion, compensated and decompensated CHF. Placement of ACF led to cardiac hypertrophy, pulmonary congestion, and renal dysfunction, which were more severe in the decompensated subgroup, despite remarkable elevation of circulatory ANP and BNP levels. Corin mRNA and immunoreactive peptide were detected in pulmonary tissue of all experimental groups. However, the expression and abundance of pulmonary corin significantly increased in the decompensated animals, but not in the compensated ones. Noteworthy, the expression of PCSK6 and ANP/BNP in the pulmonary tissue followed a similar pattern as corin. The upregulation of pulmonary Corin/PCSK6 and NPs were accompanied by local activation of cathepsin L and certain cytokines including IL-6. In light of the anti-inflammatory role of NPs, we postulate that the obtained upregulation of pulmonary PCSK6/Corin along NPs in rats with decompensated CHF may represent a counterbalance response to the inflammatory milieu characterizing CHF especially in severe cases.

Involvement of Cytokines in the Pathogenesis of Salt and Water Imbalance in Congestive Heart Failure

Congestive heart failure (CHF) has become a major medical problem in the western world with high morbidity and mortality rates. CHF adversely affects several systems, mainly the kidneys and the lungs. While the involvement of the renin-angiotensin-aldosterone system and the sympathetic nervous system in the progression of cardiovascular, pulmonary, and renal dysfunction in experimental and clinical CHF is well established, the importance of pro-inflammatory mediators in the pathogenesis of this clinical setting is still evolving. In this context, CHF is associated with overexpression of pro-inflammatory cytokines, such as tumor necrosis factor-α, interleukin (IL)-1, and IL-6, which are activated in response to environmental injury. This family of cytokines has been implicated in the deterioration of CHF, where it plays an important role in initiating and integrating homeostatic responses both at the myocardium and circulatory levels. We and others showed that angiotensin II decreased the ability of the lungs to clear edema and enhanced the fibrosis process via phosphorylation of the mitogen-activated protein kinases p38 and p42/44, which are generally involved in cellular responses to pro-inflammatory cytokines. Literature data also indicate the involvement of these effectors in modulating ion channel activity. It has been reported that in heart failure due to mitral stenosis; there were varying degrees of vascular and other associated parenchymal changes such as edema and fibrosis. In this review, we will discuss the effects of cytokines and other inflammatory mediators on the kidneys and the lungs in heart failure; especially their role in renal and alveolar ion channels activity and fluid balance.

Pathophysiology of heart failure and frailty: a common inflammatory origin?

Frailty, a clinical syndrome that typically occurs in older adults, implies a reduced ability to tolerate biological stressors. Frailty accompanies many age‐related diseases but can also occur without overt evidence of end‐organ disease. The condition is associated with circulating inflammatory cytokines and sarcopenia, features that are shared with heart failure (HF). However, the biological underpinnings of frailty remain unclear and the interaction with HF is complex. Here, we describe the inflammatory pathophysiology that is associated with frailty and speculate that the inflammation that occurs with frailty shares common origins with HF. We discuss the limitations in investigating the pathophysiology of frailty due to few relevant experimental models. Leveraging current therapies for advanced HF and current known therapies to address frailty in humans may enable translational studies to better understand the inflammatory interactions between frailty and HF.

Severe Aortic Valve Stenosis in Adults is Associated with Increased Levels of Circulating Intermediate Monocytes

Individual monocyte subsets have been associated with atherosclerotic disease, but their distribution has not been evaluated in aortic valve stenosis (AS) so far. In the present study, we have asked whether levels of the circulating intermediate monocyte subset are increased in AS. Classical (CD14++CD16-), intermediate (CD14++CD16+), and non-classical (CD14+CD16++) CD86-positive monocytes and monocyte activation (intensity of CD11b expression) were determined by flow cytometry in peripheral blood of patients with severe AS (n = 100) and matched AS-free controls (n = 75). AS patients exhibited significantly higher levels of circulating intermediate monocytes, while levels of circulating classical and non-classical monocytes or monocyte activation did not differ compared to controls. The difference in levels of intermediate monocytes between groups was independent of age, gender, BMI, LDL-C, NT-proBNP, NYHA functional class, or creatinine levels. The present pilot study provides evidence of an association of severe AS with increased levels of circulating intermediate monocytes. Further studies need to clarify whether this finding is related to the inflammatory status and hemodynamic disturbances associated with severe AS.

Orosomucoid as prognosis factor associated with inflammation in acute or nutritional status in chronic heart failure

BACKGROUND

Inflammation and nutritional state are involved in the pathogenesis of heart failure (HF).

OBJECTIVE

To study the contribution of alpha-1-acid-glycoprotein (AGP) to these factors and its prognostic value in acute (AHF) or chronic HF (CHF).

METHODS

The observational study has included 147 patients (mean age 70years, 62% men) admitted to a cardiology department for HF and followed-up for an average 326.6±140.8days. Blood AGP values were measured by Enzyme-Linked ImmunoSorbent Assay. Monocytes subsets were determined with CD14 and CD16 antibodies by flow cytometry and body composition was measured by dual-energy X-ray absorptiometry. The regulation of tumor necrosis factor (TNF-α) and leptin by AGP in epicardial adipose tissue (EAT) were analyzed by real time polymerase chain reaction.

RESULTS

High AGP, that was associated with CD14⁺CD16⁺ monocytes, and proBNP levels at the discharge were indicators of rehospitalization for HF in AHF patients. However, low AGP levels determined a worse nutritional state in CHF patients. The leptin levels were downregulated by high AGP concentration in epicardial fat.

CONCLUSION

AGP is a dual indicator in HF because high levels are predictors of adverse outcomes in AHF but low levels are related to the worse nutritional status in CHF. The regulation of leptin by AGP in epicardial fat might suggest a new pathway as protective mechanism in CHF.

Thymopentin improves cardiac function in older patients with chronic heart failure

OBJECTIVE

Recent studies have shown that activation of the immune system, inflammatory cell infiltration, and activation of inflammatory mediators play an important role in the development of heart failure. The purpose of this study was to investigate whether cardiac function can be improved by regulating the balance of lymphocyte subsets and cytokines.

METHODS

Ninety-six patients with chronic heart failure (CHF) who were older than 60 years were randomly divided into two groups: CHF testing group (CHFT) received regular therapy and thymopentin (2 mg thymopentin per day, 15th as a course, three courses in total). CHF control group (CHFC) received regular therapy. Forty-five healthy individuals older than 60 years were used as normal controls. The ejection fraction of left ventricle (LVEF), inner diameter of left ventricular end-diastole (LVEDD), inner diameter of left ventricular end-systole (LVESD), plasma high sensitive C-reactive protein (hsCRP), plasma brain natriuretic peptide (BNP), 6-min walking distance (6MWT), Minnesota Living with Heart Failure Questionnaire (MLHFQ) assessment, lymphocyte subsets, and inflammatory cytokines were tested.

RESULTS

The levels of LVEF, 6MWT, CD 3+, CD4+T cells, natural killer cells, CD4+/CD8+ and IL-10 in CHFT were increased (p<0.01) compared with CHFC, while BNP, hsCRP, MLHFQ, CD8+, TNF-α, IL-1ß, and TNF-α/IL-10 ratio in CHFT were decreased (p<0.01). LVEDD and LVESD were decreased, even though there was no significant difference between the two CHF groups.

CONCLUSION

These data suggest that immune modulation therapy improve cardiac function and regulate cytokines and lymphocyte subsets in older patients with CHF.

Perspectives for Monocyte/Macrophage-Based Diagnostics of Chronic Inflammation

Low-grade chronic inflammation underlies the development of the most dangerous cardiometabolic disorders including type 2 diabetes and its vascular complications. In contrast to acute inflammation induced by bacteria and viruses, chronic inflammation can be driven by abnormal reaction to endogenous factors, including Th2 cytokines, metabolic factors like advanced glycation end products (AGEs), modified lipoproteins, or hyperglycemia. The key innate immune cells that recognize these factors in blood circulation are monocytes. Inflammatory programming of monocytes which migrate into tissues can, in turn, result into generation of tissue macrophages with pathological functions. Therefore, determination of the molecular and functional phenotype of circulating monocytes is a very promising diagnostic tool for the identification of hidden inflammation, which can precede the development of the pathology. Here we propose a new test system for the identification of inflammatory programming of monocytes: surface biomarkers and ex vivo functional system. We summarize the current knowledge about surface biomarkers for monocyte subsets, including CD16, CCR2, CX3CR1, CD64, stabilin-1 and CD36, and their association with inflammatory human disorders. Furthermore, we present the design of an ex vivo monocyte-based test system with minimal set of parameters as a potential diagnostic tool for the identification of personalized inflammatory responses.