The role of monocytes and inflammation in the pathophysiology of heart failure

Monocytes may be favorable biomarker and predictor of long-term outcome in patients with chronic heart failure: A cohort study

Although some studies found that an increased monocyte count is a predictive, short-term marker of unfavorable outcomes for patients with acute heart failure (HF), others have reported that monocytosis predicts prolonged survival.The current follow-up study aimed to identify different monocyte count patterns and their prognostic association with HF outcomes.Baseline blood samples for complete blood counts, differential counts, renal function tests, and lipid profiles of 303 chronic HF patients (average NYHA classification 2.8) were prospectively obtained to evaluate whether there is an association between monocyte count and clinical outcomes.Mean follow-up was 11.3 years (range 1 month to 16 years) and 111 (36.6%) patients died during follow-up. Mean monocyte count was 10.6 ± 5.5 and mean left ventricular ejection fraction (LVEF) was 36%. Patients with low monocyte counts (≤6%) had significantly lower survival rates than did those with monocyte counts 6.1% to 14%, or >14% (14.3% vs 70.2% vs. 88%, P < .001). Poorest survival was predicted for patients with NYHA class 3 to 4 and monocyte counts ≤6. Regression analysis showed that monocyte levels, NYHA class, and LVEF values were predictors of mortality, in decreasing importance.The total monocyte count was found to be an important prognostic factor that was inversely associated with predicted long-term mortality among patients with chronic HF. A low total monocyte count was strongly correlated with NYHA class and B-type natriuretic peptide levels, but no correlation was found with LVEF and oxidized low-density lipoproteins. It emerged as an independent risk factor for mortality in patients with chronic HF.

Intermediate Monocytes and Cytokine Production Associated With Severe Forms of Chagas Disease

Monocytes are classified according to their CD14 and CD16 expression into classical (reparative), intermediate (inflammatory), and non-classical. This study assessed the frequency of monocyte and the relationship between monocyte subset percentages and the levels of blood cytokines in Colombian chagasic patients with different clinical forms. This study included chagasic patients in different clinical stages: indeterminate (IND) n = 14, chronic chagasic cardiomyopathy (CCC) n = 14, and heart transplant chagasic (HTCC) n = 9; controls with non-chagasic cardiopathy (NCC) n = 15, and healthy individuals (HI) n = 15. Peripheral blood mononuclear cells (PBMCs) were isolated, labeled for CD14, CD16, and HLA-DR, and analyzed by flow cytometry. Cytokines were measured with a bead-based immunoassay. Percentages of total CD14+ CD16+ and CD14+ HLA-DR+ monocytes were higher in patients with heart involvement (CCC, HTCC, and NCC) than controls. Percentages of intermediate monocytes increased in symptomatic chagasic patients (CCC and HTCC) compared to asymptomatic chagasic patients (IND) and controls (HI). Asymptomatic chagasic patients (IND) had higher percentages of classical monocytes, an increased production of CCL17 chemokine compared to chagasic symptomatic patients (CCC), and their levels of CCL17 was positively correlated with the percentage of classical monocyte subset. In CCC, the percentages of intermediate and classical monocytes were positively correlated with IL-6 levels, which were higher in this group compared to HI, and negatively with IL-12p40 concentration, respectively. Remarkably, there also was an important increased of classical monocytes frequency in three chronic chagasic patients who underwent cardiac transplant, of which one received anti-parasitic treatment. Our findings suggest that cardiac chagasic patients have an increased percentage of inflammatory monocytes and produce more IL-6, a biomarker of heart failure and left ventricular dysfunction, whereas asymptomatic chagasic individuals present a higher percentage of reparative monocytes and CCL17.

Plasma Lipopolysaccharide Concentrations in Cardiorenal Syndrome Type 1

BACKGROUND

Cardiorenal syndrome (CRS) type 1 is characterized by a rapid worsening of cardiac function that leads to acute kidney injury (AKI). This study evaluated the role of lipopolysaccharide (LPS) in the development of AKI in patients with acute heart failure (AHF) and its relationship with renal parameters, to enable a better comprehension of the pathophysiology of CRS type 1.

METHODS

We enrolled 32 AHF patients, 15 of whom were classified as having CRS type 1. Eight of these 15 exhibited AKI at the time of admission (caused by AHF) and the other 7 developed AKI during their stay in hospital (in the first 48 h). We evaluated the plasmatic LPS concentrations as well as conventional (serum creatinine [sCr] and urea) and unconventional (neutrophil gelatinase-associated lipocalin [NGAL] and cystatin C) renal markers.

RESULTS

LPS levels were significantly higher in the CRS type 1 patients. No significant difference in LPS level was found in patients who were admitted with AKI and those developed AKI in hospital, but there was a tendency towards a higher level of LPS in CRS type 1 patients admitted with AKI. The LPS concentrations at admission were similar in CRS type 1 survivors (n = 12) and nonsurvivors (n = 3) (p = 0.22). We observed a positive correlation between LPS level and NGAL, Scr at admission and peak Scr during hospitalization and urea at admission.

CONCLUSION

CRS type 1 patients present with an increased level of LPS and there is a direct correlation between LPS and renal parameters. This pilot research is the first study to explore the premise of LPS as novel pathophysiological factor in CRS type 1.

Expression of socially sensitive genes: The multi-ethnic study of atherosclerosis

BACKGROUND

Gene expression may be an important biological mediator in associations between social factors and health. However, previous studies were limited by small sample sizes and use of differing cell types with heterogeneous expression patterns. We use a large population-based cohort with gene expression measured solely in monocytes to investigate associations between seven social factors and expression of genes previously found to be sensitive to social factors.

METHODS

We employ three methodological approaches: 1) omnibus test for the entire gene set (Global ANCOVA), 2) assessment of each association individually (linear regression), and 3) machine learning method that performs variable selection with correlated predictors (elastic net).

RESULTS

In global analyses, significant associations with the a priori defined socially sensitive gene set were detected for major or lifetime discrimination and chronic burden (p = 0.019 and p = 0.047, respectively). Marginally significant associations were detected for loneliness and adult socioeconomic status (p = 0.066, p = 0.093, respectively). No associations were significant in linear regression analyses after accounting for multiple testing. However, a small percentage of gene expressions (up to 11%) were associated with at least one social factor using elastic net.

CONCLUSION

The Global ANCOVA and elastic net findings suggest that a small percentage of genes may be "socially sensitive," (i.e. demonstrate differential expression by social factor), yet single gene approaches such as linear regression may be ill powered to capture this relationship. Future research should further investigate the biological mechanisms through which social factors act to influence gene expression and how systemic changes in gene expression affect overall health.

Intraoperative Management of a Patient With Impaired Cardiac Function Undergoing Simultaneous ABO-Compatible Liver and ABO-Incompatible Kidney Transplant From 2 Living Donors: A Case Report

BACKGROUND

Combined liver and kidney transplant is a very complex surgery. To date, there has been no report on the intraoperative management of patients with impaired cardiac function undergoing simultaneous ABO-compatible liver and ABO-incompatible kidney transplant from 2 living donors.

CASE REPORT

A 60-year-old man underwent simultaneous ABO-compatible liver and ABO-incompatible kidney transplant from 2 living donors because of IgA nephropathy and alcoholic liver cirrhosis. The preoperative cardiac findings revealed continuous aggravation, shown by large left atrial enlargement, severe left ventricular hypertrophy, a very prolonged QT interval, and a calcified left anterior descending coronary artery. Severe hypotension with very weak pulsation and severe bradycardia developed, with an irregular junctional rhythm noted immediately after the liver graft was reperfused. Although epinephrine was administered as a rescue drug, hemodynamics did not improve, and central venous pressure and mean pulmonary arterial pressure increased to potentially fatal levels. Emergency phlebotomy via the central line was performed. Thereafter, hypotension and bradycardia recovered gradually as the central venous pressure and mean pulmonary arterial pressure decreased. The irregular junctional rhythm returned to a sinus rhythm, but the QTc interval was slightly more prolonged. Because of poor cardiac capacity, the volume and rate of fluid infusion were increased aggressively to maintain appropriate kidney graft perfusion after confirming vigorous urine production of the graft.

CONCLUSIONS

A heart with impaired function due to both end-stage liver and kidney diseases may be less able to withstand surgical stress. Further study on cardiac dysfunction will be helpful for the management of patients undergoing complex transplant surgery.

Serum Albumin at Start of Peritoneal Dialysis Predicts Long-Term Outcomes in Anhui Han Patients on Continuous Ambulatory Peritoneal Dialysis: A Retrospective Cohort Study

Objective

This study assessed the relationship between serum albumin (ALB) at start of peritoneal dialysis (PD) and long-term outcomes of continuous ambulatory PD (CAPD) in Anhui Han patients.

Methods

A total of 149 Anhui Han CAPD patients were enrolled in this study and followed up for 3 years. They were initially diagnosed with the end-stage renal disease and underwent surgical PD catheter placement from January 2009 to December 2013. According to serum ALB at start of PD, the patients were divided into two groups: low ALB group (ALB < 35 g/L) and high ALB group (ALB ≥35 g/L). Demographic, hematologic, biochemical, and dialysis-related data were collected. Kaplan-Meier survival analysis and log-rank test were conducted to compare patient mortality, cardiovascular mortality and technique failure between the low ALB group and the high ALB group. Cox regression analysis was performed to analyze the risk factors, calculate the hazard ratio (HR), adjusted HR (AHR) and 95% confidence interval (CI).

Results

The low ALB group showed a greater number of diabetes mellitus compared with the high ALB group. Patient mortality, cardiovascular mortality, and technique failure in the high ALB group were significantly lower than those in the low ALB group. In Cox regression analysis, serum ALB < 35 g/L was an independent predictor of patient mortality (AHR 3.043, 95% CI 1.085-8.536, p = 0.034), cardiovascular mortality (AHR 11.587, 95% CI 1.466-91.574, p = 0.020), and technique failure (AHR 3.148, 95% CI 1.603-6.182, p = 0.001) in CAPD patients after adjustment for sex, age, estimated glomerular filtration rate, primary renal disease, diabetes mellitus, and cardiovascular disease.

Conclusions

In Anhui Han patients on CAPD, the levels of serum ALB at start of PD are inversely correlated with patient mortality, cardiovascular mortality, and technique failure, and the long-term outcomes of patients with hypoalbuminemia at start of PD are poor. To improve the long-term outcomes of Anhui Han CAPD patients, patients with hypoalbuminemia at start of PD should be closely monitored.

Inflammation in Right Ventricular Failure: Does It Matter?

Right ventricular (RV) failure is a common consequence of acute and chronic RV overload of pressure, such as after pulmonary embolism and pulmonary hypertension. It has been recently realized that symptomatology and survival of patients with pulmonary hypertension are essentially determined by RV function adaptation to increased afterload. Therefore, improvement of RV function and reversal of RV failure are treatment goals. Currently, the pathophysiology and the pathobiology underlying RV failure remain largely unknown. A better understanding of the pathophysiological processes involved in RV failure is needed, as there is no proven treatment for this disease at the moment. The present review aims to summarize the current understanding of the pathogenesis of RV failure, focusing on inflammation. We attempt to formally emphasize the importance of inflammation and associated representative inflammatory molecules and cells in the primum movens and development of RV failure in humans and in experimental models. We present inflammatory biomarkers and immune mediators involved in RV failure. We focus on inflammatory mediators and cells which seem to correlate with the deterioration of RV function and also explain how all these inflammatory mediators and cells might impact RV function adaptation to increased afterload. Finally, we also discuss the evidence on potential beneficial effects of targeted anti-inflammatory agents in the setting of acute and chronic RV failure.

Design of the GutHeart-targeting gut microbiota to treat heart failure-trial: a Phase II, randomized clinical trial

Aims

Heart failure (HF) is a multifactorial disease. Current treatments target only a fraction of the putative pathophysiological pathways. In patients with HF, reduced cardiac output and congestion cause increased gut wall permeability. It has been suggested that leakage of microbial products is detrimental to the heart, at least partly through activation of systemic inflammatory pathways, which again could promote gut leakage. Whether manipulating the gut microbiota can improve cardiac function in patients with HF remains unknown. We aim to evaluate the effect of drugs targeting the gut microbiota on left ventricular function, quality of life, and functional capacity, as well as on markers of gut leakage and inflammation, in stable patients with HF with reduced ejection fraction.

Methods and results

GutHeart is a randomized, open‐label, controlled trial. Four centres will randomize 150 patients with stable HF and a left ventricular ejection fraction <40% to receive the antibiotic rifaximin, the probiotic yeast Saccharomyces boulardii (ATCC 74012), or no treatment (control) in a 1:1:1 fashion. Treatment will last for 3 months. The primary endpoint is baseline‐adjusted left ventricular ejection fraction as measured by echocardiography after 3 months. A further follow‐up 6 months after randomization will be undertaken.

Conclusions

This trial is likely to give new insights into important disease processes involving the gut microbiota in HF patients, hereby leading to new potential therapeutic strategies to prevent and down‐regulate the inflammation seen in these patients.

T cell and monocyte/macrophage activation markers associate with adverse outcome, but give limited prognostic value in anemic patients with heart failure: results from RED-HF

BACKGROUND

Activated leukocytes may contribute to the development and progression of heart failure (HF). We investigated the predictive value of circulating levels of stable and readily detectable markers reflecting both monocyte/macrophage and T-cell activity, on clinical outcomes in HF patients with reduced ejection fraction (HFrEF).

METHODS

The association between baseline plasma levels of soluble CD163 (sCD163), macrophage migration inhibitory factor (MIF), granulysin, soluble interleukin-2 receptor (sIL-2R), and activated leukocyte cell adhesion molecule (ALCAM) and the primary endpoint of death from any cause or first hospitalization for worsening of HF was evaluated using multivariable Cox proportional hazard models in 1541 patients with systolic HF and mild to moderate anemia, enrolled in the Reduction of Events by darbepoetin alfa in Heart Failure (RED-HF) trial. Modifying effects and interaction with darbepoetin alfa treatment were also assessed.

RESULTS

All leukocyte markers, except granulysin, were associated with the primary outcome and all-cause death in univariate analysis (all p < 0.01) and remained significantly associated in multivariable analysis adjusting for conventional clinical variables (e.g. age, gender, BMI, NYHA class, creatinine, LVEF, etiology) and CRP. However, after final adjustment for TnT and NT-proBNP no associations were found with outcomes. No interaction with darbepoetin alpha treatment was observed for any marker.

CONCLUSIONS

Leukocyte activation markers sCD163, MIF, sIL-2R, and ALCAM were associated with adverse outcome in patients with HFrEF, but add little as prognostic markers on top of established biochemical risk markers.

CLINICAL TRIAL REGISTRATION

https://clinicaltrials.gov/ct2/show/NCT00358215 .

Effect of albumin-globulin score and albumin to globulin ratio on survival in patients with heart failure: a retrospective cohort study in China

OBJECTIVE

To investigate the combined effect of albumin (ALB) and globulin (GLB) on the overall survival (OS) of patients with heart failure (HF).

DESIGN

Retrospective cohort study.

SETTING

A hospital.

PARTICIPANTS

404 patients first diagnosed with HF.

MEASUREMENTS

Serum ALB and GLB were measured within 3 days after admission. The albumin to globulin ratio (AGR) was calculated as the ALB divided by the GLB. The receiver operating characteristic curve was used to calculate the cut-off points for ALB, GLB and AGR. Patients with low ALB levels (≤35.3 g/L) and high GLB levels (>27.0 g/L) were assigned an albumin-globulin score (AGS) of 2, those with only one of the two abnormalities were assigned an AGS of 1 and those with neither of the two abnormalities were assigned an AGS of 0.

RESULTS

The mean age of the 404 patients was 62.69±15.62, and 54.5% were male. 14 patients were lost to follow-up. 120 patients died from HF and 211 patients were readmitted to the hospital for worsening HF. Multivariate Cox regression analysis showed that higher AGR was significantly associated with favourable OS (HR, 0.61, 95% CI 0.38 to 0.98, p=0.040) but not AGS.

CONCLUSION

Serum levels of ALB and GLB are objective and easily measurable biomarkers which can be used in combination to predict the survival of patients with HF.

Prognostic value of the absolute lymphocyte count in patients admitted for acute heart failure

BACKGROUND

Low relative lymphocyte count is an important prognostic marker in acute heart failure (AHF); however, it could be influenced by other abnormalities in white cells count. Our purpose is to evaluate if low absolute lymphocyte count (ALC) is an independent predictor of events in patients with AHF.

METHODS

In a retrospective analysis, we included 309 patients with AHF, divided into two groups according to the median value of ALC at admission (1410 cells/μl). The primary end point was all-cause mortality or urgent heart transplantation within 1 year.

RESULTS

Patients with low ALC were older and had more comorbidity, namely atrial fibrillation, chronic kidney disease, chronic obstructive pulmonary disease and anemia. Low ALC was associated with higher all-cause mortality or urgent heart transplantation at 1 year (24.3 vs 13.0%; P = 0.012). In a multivariable model, the independent predictors of mortality at 1 year were ALC 1410 cells/μl or less at admission [hazard ratio 2.04; CI (confidence interval) 95% (1.06-3.95); P = 0.033], age [hazard ratio 1.08; CI 95% (1.04-1.12); P < 0.001], baseline serum creatinine [hazard ratio 1.25; CI 95% (1.05-1.50); P = 0.012] and baseline serum Na [hazard ratio 0.91; CI 95% (0.85-0.98); P = 0.013].

CONCLUSION

Low ALC in patients with AHF is associated with higher in-hospital mortality during the hospitalization and is an independent predictor of long-term mortality.

Monocyte Response to Different Campylobacter jejuni Lysates Involves Endoplasmic Reticulum Stress and the Lysosomal⁻Mitochondrial Axis: When Cell Death Is Better Than Cell Survival

Campylobacter jejuni is a Gram-negative spiral-shaped bacterium, commonly associated with gastroenteritis in humans. It explicates its virulence also by the cytolethal distending toxin (CDT), able to cause irreversible cell cycle arrest. Infection by C. jejuni may result in the development of the Guillain⁻Barré Syndrome, an acute peripheral neuropathy. Symptoms of this disease could be caused by CDT-induced cell death and a subsequent inflammatory response. We tested C. jejuni lysates from different strains on donor monocytes: in fact, monocytes are potent producers of both pro- and anti-inflammatory cytokines, playing a major role in innate immunity and in non-specific host responses. We found, by cytometric and confocal analyses, that mitochondria and lysosomes were differently targeted: The C. jejuni strain that induced the most relevant mitochondrial alterations was the ATCC 33291, confirming an intrinsic apoptotic pathway, whereas the C. jejuni ISS 1 wild-type strain mostly induced lysosomal alterations. Lysates from all strains induced endoplasmic reticulum (ER) stress in monocytes, suggesting that ER stress was not associated with CDT but to other C. jejuni virulence factors. The ER data were consistent with an increase in cytosolic Ca2+ content induced by the lysates. On the contrary, the changes in lysosomal acidic compartments and p53 expression (occurring together from time 0, T0, to 24 h) were mainly due to CDT. The loss of p53 may prevent or impede cell death and it was not observable with the mutant strain. CDT not only was responsible for specific death effects but also seemed to promote an apoptotic stimuli-resisting pathway.

More intensive CMV-infection in chronic heart failure patients contributes to higher T-lymphocyte differentiation degree

Immunosenescence in chronic heart failure (CHF) is characterized by a high frequency of differentiated T-lymphocytes, contributing to an inflammatory status and a deficient ability to generate immunocompetent responses. CMV is the best known inducer of T-lymphocyte differentiation, and is associated with the phenomenon of immunosenescence. In this study, we included 58 elderly chronic heart failure patients (ECHF), 60 healthy elderly controls (HEC), 40 young chronic heart failure patients (YCHF) and 40 healthy young controls (HYC). High differentiation of CD8+ T-lymphocytes was found in CMV-seropositive patients; however, the differentiation of CD4+ T-lymphocytes was increased in CMV-seropositive but also in CHF patients. Anti-CMV antibody titers showed positive correlation with more differentiated CD4+ and CD8+ subsets and inverse correlation with CD4/CD8 ratio. Immunosenescence found in CHF patients is mainly due to the dynamics of CMV-infection, since the differentiation of T-lymphocyte subsets is related not only to CMV-infection, but also to anti-CMV antibody titers.

Leukocyte-Associated Immunoglobulin-like Receptor-1 is regulated in human myocardial infarction but its absence does not affect infarct size in mice

Heart failure after myocardial infarction (MI) depends on infarct size and adverse left ventricular (LV) remodelling, both influenced by the inflammatory response. Leukocyte-associated immunoglobulin-like receptor 1 (LAIR-1) is an inhibitory receptor of ITAM-dependent cell activation, present on almost all immune cells. We investigated regulation of LAIR-1 leukocyte expression after MI in patients and hypothesized that its absence in a mouse model of MI would increase infarct size and adverse remodelling. In patients, LAIR-1 expression was increased 3 days compared to 6 weeks after MI on circulating monocytes (24.8 ± 5.3 vs. 21.2 ± 5.1 MFI, p = 0.008) and neutrophils (12.9 ± 4.7 vs. 10.6 ± 3.1 MFI, p = 0.046). In WT and LAIR-1^-/- mice, infarct size after ischemia-reperfusion injury was comparable (37.0 ± 14.5 in WT vs. 39.4 ± 12.2% of the area at risk in LAIR-1^-/-, p = 0.63). Remodelling after permanent left coronary artery ligation did not differ between WT and LAIR-1^-/- mice (end-diastolic volume 133.3 ± 19.3 vs. 132.1 ± 27.9 μL, p = 0.91 and end-systolic volume 112.1 ± 22.2 vs. 106.9 ± 33.5 μL, p = 0.68). Similarly, no differences were observed in inflammatory cell influx or fibrosis. In conclusion, LAIR-1 expression on monocytes and neutrophils is increased in the acute phase after MI in patients, but the absence of LAIR-1 in mice does not influence infarct size, inflammation, fibrosis or adverse cardiac remodelling.

Hemographic indices are associated with mortality in acute heart failure

Hemographic indices have been associated with clinical outcomes in patients with chronic heart failure. We therefore investigated the prognostic values of hemographic indices in patients hospitalized for acute heart failure (AHF). Patients hospitalized primarily for AHF were drawn from an intramural registry. Hemographic indices, including white blood cell counts, neutrophil counts, neutrophil-to-lymphocyte ratio, reciprocal of lymphocyte (RL) and platelet-to-lymphocyte ratio were recorded. Among a total of 1923 participants (mean age 76 ± 12 years, 68% men), 875 patients died during a mean follow-up of 28.6 ± 20.7 months. Except for white blood cell counts, all the other hemographic indices were related to mortality, independently. In a forward stepwise Cox regression analysis among hemographic indices, RL was the strongest predictor (HR and 95% CI per-1SD:1.166,1.097-1.240) for mortality, after accounting for confounders. However, conditioned on the survivals, the hemographic indices were independently related to mortality within 3 years of follow-up, rather than beyond. Hemographic indices were independent risk factors of mortality in patients hospitalized for AHF, especially in patients with impaired left ventricular systolic function. As an acute presentation of inflammation, hemographic indices might be useful to identify subjects at risk of mortality soon after the index hospitalization.

Increased expression of cell adhesion molecule receptors on monocyte subsets in ischaemic heart failure

The objective of this study was to evaluate the expression of cell adhesion molecule (CAM) receptors (integrins) on monocyte subsets in heart failure (HF) and examine their prognostic implication. Increased levels of soluble CAMs have been observed in patients with HF, but the precise mechanism of monocyte adhesion to the vascular endothelium remains unknown. Patients with acute HF (AHF, n=51) were compared to those with stable HF (SHF, n=42) and stable coronary artery disease (CAD, n=44) without HF. Expression of integrins-receptors to intercellular adhesion molecule-1 (ICAM-1R) and vascular CAM-1 (VCAM-1R) on monocyte subsets was assessed by flow cytometry. Monocyte subsets were defined as CD14++CD16–CCR2+ (‘classical’, Mon1), CD14++CD16+CCR2+ (‘intermediate’, Mon2), and CD14+CD16++CCR2– (‘non-classical’, Mon3). Compared to patients with SHF, those with AHF had significantly higher expression of ICAM-1R on Mon2 (p=0.01). Compared to those with stable CAD, patients with SHF had a significantly higher expression of ICAM-1R on Mon2 (p=0.025). Compared to SHF, patients with AHF had a similar expression of VCAM-1R on both Mon1 and Mon3 but significantly higher expression on Mon2 (p=0.019). There were no significant differences between SHF and CAD in monocyte expression of VCAM-1R. In multivariate Cox regression analysis, VCAM-1R expression on Mon2 was associated with adverse clinical outcome (death or rehospitalisation) in AHF [HR 1.07 (1.01–1.14), p=0.029]. In conclusion, HF is associated with increased monocyte expression of integrins-receptors to both ICAM-1 and VCAM-1, being particularly linked to Mon2 subset. Expression of VCAM-1R on Mon2 may have prognostic value in patients with AHF.

The Physiopathology of Cardiorenal Syndrome: A Review of the Potential Contributions of Inflammation

Inter-organ crosstalk plays an essential role in the physiological homeostasis of the heart and other organs, and requires a complex interaction between a host of cellular, molecular, and neural factors. Derangements in these interactions can initiate multi-organ dysfunction. This is the case, for instance, in the heart or kidneys where a pathological alteration in one organ can unfavorably affect function in another distant organ; attention is currently being paid to understanding the physiopathological consequences of kidney dysfunction on cardiac performance that lead to cardiorenal syndrome. Different cardiorenal connectors (renin-angiotensin or sympathetic nervous system activation, inflammation, uremia, etc.) and non-traditional risk factors potentially contribute to multi-organ failure. Of these, inflammation may be crucial as inflammatory cells contribute to over-production of eicosanoids and lipid second messengers that activate intracellular signaling pathways involved in pathogenesis. Indeed, inflammation biomarkers are often elevated in patients with cardiac or renal dysfunction. Epigenetics, a dynamic process that regulates gene expression and function, is also recognized as an important player in single-organ disease. Principal epigenetic modifications occur at the level of DNA (i.e., methylation) and histone proteins; aberrant DNA methylation is associated with pathogenesis of organ dysfunction through a number of mechanisms (inflammation, nitric oxide bioavailability, endothelin, etc.). Herein, we focus on the potential contribution of inflammation in pathogenesis of cardiorenal syndrome.

Pterostilbene reduces oxidative stress, prevents hypertrophy and preserves systolic function of right ventricle in cor pulmonale model

BACKGROUND AND PURPOSE

In cor pulmonale, the increased afterload imposed on the right ventricle (RV) generates a maladaptive response, impairing the contractile cardiac function. Oxidative mechanisms play an important role in the pathophysiology and progression of this disease. The administration of pterostilbene (PTS), a phytophenol with antioxidant potential, may represent a therapeutic option. In the present study, we evaluated the effect of PTS complexed with hydroxypropyl-β-cyclodextrin (HPβCD) on hypertrophy, contractile function and oxidative parameters in the RV of rats with pulmonary hypertension, induced by the administration of monocrotaline (MCT).

EXPERIMENTAL APPROACH

The rats received daily doses of the PTS : HPβCD complex at 25, 50 or 100 mg·kg^-1 , p.o., for 14 days. The diastolic function, E/A ratio, and systolic function, shortening fraction, fractional area change (FAC) and tricuspid annular plane systolic excursion (TAPSE) of the RV were determined by echocardiography.

KEY RESULTS

The PTS : HPβCD complex reduced the production of NADPH oxidase-dependent superoxide anions and oxidative stress in the RV of MCT-treated rats in a dose-dependent manner. At higher doses it prevented the reduction in FAC and TAPSE in MCT-treated animals.

CONCLUSIONS AND IMPLICATIONS

The PTS : HPβCD complex prevented the maladaptative remodelling and protected systolic function in the RV of rats with pulmonary hypertension. These cardioprotective mechanisms may be related, in part, to the antioxidant potential of PTS, favoured by the increased p.o. bioavailability promoted by the presence of HPβCD in the complex.

Nutritional intervention in acute heart failure patients with undernutrition and normalbuminemia: A subgroup analysis of PICNIC study

BACKGROUND & AIMS

Hypoalbuminemia is common in acute heart failure (HF) patients and has been associated with increased hospital mortality and long-term mortality. Undernutrition is a factor causing hypoalbuminemia. The PICNIC study results show that a nutritional intervention in undernourished acute HF patients reduces the risks of all-cause death and of readmission for HF. We aimed to investigate whether the efficacy of a nutritional intervention is consistent among the subgroups of patients with and without hypoalbuminemia.

METHODS

In PICNIC study, a total of 120 malnourished hospitalized patients due to acute HF were randomized to conventional HF treatment or conventional HF treatment combined with an individualized nutritional intervention. The primary endpoint was a composite of all-cause death or readmission for worsening of HF, with a maximum follow-up of 12 months. In this post-hoc sub-analysis we assessed the interaction of the effects of a nutritional intervention among patients with and without hypoalbuminemia. Analysis was by intention to treat.

RESULTS

59 (49,2%) patients demonstrated hypoalbuminemia and 61 (50,8%) had normalbuminemia. At 12 months, the number of events for the primary endpoint in the intervention group compared with the control group was consistent among patients with hypoalbuminemia (28.6% intervention vs 61.3% control, HR 0,35, 95% CI 0,15-0,81) and those without (25.8% intervention vs 60% control, HR 0,35, 95% CI 0,15-0,79; interaction p = 0,86).

CONCLUSION

There was no evidence that the relative efficacy of a nutritional intervention in undernourished acute HF patients was different between patients with normalbuminemia and those with hypoalbuminemia.

Epigenetics, inflammation and metabolism in right heart failure associated with pulmonary hypertension

Right ventricular failure (RVF) is the most important prognostic factor for both morbidity and mortality in pulmonary arterial hypertension (PAH), but also occurs in numerous other common diseases and conditions, including left ventricle dysfunction. RVF remains understudied compared with left ventricular failure (LVF). However, right and left ventricles have many differences at the morphological level or the embryologic origin, and respond differently to pressure overload. Therefore, knowledge from the left ventricle cannot be extrapolated to the right ventricle. Few studies have focused on the right ventricle and have permitted to increase our knowledge on the right ventricular-specific mechanisms driving decompensation. Here we review basic principles such as mechanisms accounting for right ventricle hypertrophy, dysfunction, and transition toward failure, with a focus on epigenetics, inflammatory, and metabolic processes.

Myoblast transplantation improves cardiac function after myocardial infarction through attenuating inflammatory responses

Myocardial infarction (MI) is a highly prevalent cardiac emergency, which results in adverse cardiac remodeling and then exacerbates progressive heart failure. Inflammatory responses in cardiac tissue after MI is necessary for myocardium repair and wound healing. However, the excessive inflammation is also a key component of subsequent heart failure pathology. Myoblast transplantation after MI have been fulfilled attractive effects on cardiac repair, but the complications of transplantation and the underlying mechanisms have not been fully elucidated. Here, we found that human myoblast transplantation into minipig myocardium decreased the infiltration of inflammatory cells, the expression levels of many pro-inflammatory genes and the activation of inflammation-related signal pathways, while upregulated the expression levels of anti-inflammatory genes such as IL-10 in cardiac tissue of minipig post-MI, which was contributed to the improved cardiac function, the decreased infarct area and the attenuated myocardial fibrosis. Moreover, co-culture of human myoblasts inhibited the production of IL-1β and TNF-α as well as activation of MAPK and NF-κB signaling pathway induced by damage-associated molecular patterns such as HMGB1 and HSP60 in human THP-1 cells, which was partially attributed to the up-regulated production of IL-10. Collectively, these results indicate that myoblast transplantation ameliorates heart injury and improves cardiac function post-MI through inhibiting the inflammatory response, which provides the novel mechanism for myoblast transplantation therapy of MI.

Oral health and cardiovascular disease risk in a cohort of periodontitis patients

BACKGROUND AND AIMS

The aim of this study was to determine whether oral health is uniformly associated with three different cardiovascular diseases (CVDs), including myocardial infarction (MI), stroke, and heart failure (HF), which has not been studied previously.

METHODS

A full mouth investigation was performed in 8999 individuals referred to a specialized periodontology clinic between 1979 and 2012. The number of deepened pockets (NDP), number of teeth (NT), and bleeding on probing (BOP) were investigated. Incident CVD diagnosis was obtained from the Swedish cause of death and the hospital discharge registers.

RESULTS

During a median follow-up time of 15.8 years (153,103 person years at risk), 1338 incident cases of fatal/non-fatal CVD occurred (672 fatal/non-fatal MI, 545 stroke and 302 HF). When NT, BOP and NDP were all included in the same model with age, sex, smoking, calendar time, and education level, NT and NDP, but not BOP, were significantly related to future CVD (combined end-point, p = 0.0003 for NT and p = 0.007 for NDP). In similar analyses of 3 separate CVD outcomes, NT was significantly related to MI, with an incidence rate ratio (IRR) for a given interquartile range change of 0.90 (95% CI 0.82-0.99) and to HF, with an IRR of 0.87 (95% CI 0.77-0.99). However, NT was not significantly related to stroke. BOP and NDP were not significantly related to any of the three separate CVD outcomes.

CONCLUSION

Oral health, mainly represented by NT, was related to incident MI and HF, but not to incident stroke. Therefore, oral health does not seem to relate to all major CV disorders in a similar fashion.

Presepsin (sCD14-ST) Is a Novel Marker for Risk Stratification in Cardiac Surgery Patients

Background

Presepsin (soluble cluster-of-differentiation 14 subtype [sCD14-ST]) is a humoral risk stratification marker for systemic inflammatory response syndrome and sepsis. It remains unknown whether presepsin can be used to stratify risk in elective cardiac surgery. The authors therefore determined the usefulness of presepsin for risk stratification in patients having elective cardiac surgery.

Methods

Eight hundred fifty-six cardiac surgical patients were prospectively studied. Preoperative plasma concentrations of presepsin, procalcitonin, N-terminal pro–hormone natriuretic peptide, cystatin C, and the additive European System of Cardiac Operative Risk Evaluation 2 were compared to mortality at 30 days (primary outcome), 6 months, and 2 yr. Discrimination was assessed with C statistic. Logistic regression analysis was used to calculate univariable and multivariable odds ratios.

Results

Thirty-day mortality was 3.2%, 6-month mortality was 6.1%, and 2-yr mortality was 10.4% across the population. Median preoperative presepsin concentrations were significantly greater in 30-day nonsurvivors than in survivors: 842 pg/ml (interquartile range, 306 to 1,246) versus 160 pg/ml (interquartile range, 122 to 234); difference, 167 pg/ml (interquartile range, 92 to 301; P &lt; 0.001). The results were similar for 6-month and 2-yr mortality. Compared to the European System of Cardiac Operative Risk Evaluation 2, presepsin concentration provided better discrimination for postoperative mortality at all follow-up periods, including 30 days (C statistic 0.88 vs. 0.74), 6 months (0.87 vs. 0.76), and 2 yr (0.81 vs. 0.74). Presepsin also provided better discrimination than cystatin C, N-terminal pro–hormone natriuretic peptide, or procalcitonin. Elevated presepsin remained an independent risk predictor after adjustment for potential confounding factors.

Conclusions

Elevated preoperative plasma presepsin concentration is an independent predictor of postoperative mortality in elective cardiac surgery patients and is a stronger predictor than several other commonly used assessments.

Poor Response to Periodontal Treatment May Predict Future Cardiovascular Disease

Periodontal disease has been associated with cardiovascular disease (CVD), but whether the response to the treatment of periodontal disease affects this association has not been investigated in any large prospective study. Periodontal data obtained at baseline and 1 y after treatment were available in 5,297 individuals with remaining teeth who were treated at a specialized clinic for periodontal disease. Poor response to treatment was defined as having >10% sites with probing pocket depth >4 mm deep and bleeding on probing at ≥20% of the sites 1 y after active treatment. Fatal/nonfatal incidence rate of CVD (composite end point of myocardial infarction, stroke, and heart failure) was obtained from the Swedish cause-of-death and hospital discharge registers. Poisson regression analysis was performed to analyze future risk of CVD. During a median follow-up of 16.8 y (89,719 person-years at risk), those individuals who did not respond well to treatment (13.8% of the sample) had an increased incidence of CVD ( n = 870) when compared with responders (23.6 vs. 15.3%, P < 0.001). When adjusting for calendar time, age, sex, educational level, smoking, and baseline values for bleeding on probing, probing pocket depth >4 mm, and number of teeth, the incidence rate ratio for CVD among poor responders was 1.28 (95% CI, 1.07 to 1.53; P = 0.007) as opposed to good responders. The incidence rate ratio among poor responders increased to 1.39 (95% CI, 1.13 to 1.73; P = 0.002) for those with the most remaining teeth. Individuals who did not respond well to periodontal treatment had an increased risk for future CVD, indicating that successful periodontal treatment might influence progression of subclinical CVD.

ERBB signaling attenuates proinflammatory activation of nonclassical monocytes

Immune activation in chronic systolic heart failure (HF) correlates with disease severity and prognosis. Recombinant neuregulin-1 (rNRG-1) is being developed as a possible therapy for HF, based on the activation of ERBB receptors in cardiac cells. Work in animal models of HF led us to hypothesize that there may be direct effects of NRG-1 on immune system activation and inflammation. We investigated the expression of ERBB receptors and the effect of rNRG-1 isoform glial growth factor 2 (GGF2) in subpopulations of peripheral blood mononuclear cells (PB MNCs) in subjects with HF. We found that human monocytes express both ERBB2 and ERBB3 receptors, with high interindividual variability among subjects. Monocyte surface ERBB3 and TNF-α mRNA expression were inversely correlated in subjects with HF but not in human subjects without HF. GGF2 activation of ERBB signaling ex vivo inhibited LPS-induced TNF-α production, specifically in the CD14^lowCD16⁺ population of monocytes in a phosphoinositide 3-kinase-dependent manner. GGF2 suppression of TNF-α correlated directly with the expression of ERBB3. In vivo, a single dose of intravenous GGF2 reduced TNF-α expression in PB MNCs of HF subjects participating in a phase I safety study of GGF2. These results support a role for ERBB3 signaling in the regulation of TNF-α production from CD14^lowCD16⁺ monocytes and a need for further investigation into the clinical significance of NRG-1/ERBB signaling as a modulator of immune system function.NEW & NOTEWORTHY This study identified a novel role of neuregulin-1 (NRG-1)/ERBB signaling in the control of proinflammatory activation of monocytes. These results further improve our fundamental understanding of cardioprotective effects of NRG-1 in patients with heart failure.

Risk Factors for Intrapartum Fever in Term Gestations and Associated Maternal and Neonatal Sequelae

AIM

To determine factors associated with intrapartum fever and to examine associated maternal and neonatal outcomes.

METHODS

Retrospective study of patients between 360/7 and 420/7 gestational weeks who entered spontaneous or induced active labor and developed temperature ≥38°C; a similar group that did not develop fever were controls. Univariate and multivariate analyses were performed with p < 0.05 as significant.

RESULTS

Fifty-four febrile patients and 306 nonfebrile controls met inclusion criteria. Nulligravidity (45.8 vs. 77.8%, p < 0.001), length of first stage ≥720 min (OR 3.59, 95% CI 1.97-6.55, p < 0.001), length of second stage ≥120 min (OR 4.76, 95% CI 2.29-9.89, p < 0.001), membrane rupture ≥240 min (46.4 vs. 79.6%, p < 0.001), increasing number of vaginal exams (4 vs. 6, p < 0.001), oxytocin (44.8 vs. 63.0%, p = 0.014), and meperidine (14.7 vs. 35.2%, p < 0.001) were all associated with intrapartum fever. Associated morbidity included cesarean delivery (22.5 vs. 44.4%, p = 0.001), Apgar score <7 at 5 min (0.7 vs. 5.6%, p = 0.011), and neonatal intensive care unit admission (9.5 vs. 51.9%, p < 0.001).

CONCLUSION

We have identified several noninfectious factors that are associated with intrapartum fever. Modification of risk factors may improve both maternal and neonatal outcomes.

Mesenchymal Stem Cell Therapy for the Treatment of Heart Failure Caused by Ischemic or Non-ischemic Cardiomyopathy: Immunosuppression and Its Implications

HF patients with signs and symptoms of worsening heart failure (HF), despite optimal medical therapy, have a poor prognosis. The pathways contributing to HF are multiple, probably accounting, in part, for current treatment approaches not being more effective. Stem cells, particularly mesenchymal stem cells (MSCs), have a broad range of activities, making them particularly interesting candidates for a new HF therapeutic. This review presents an overview of the studies examining the efficacy of stem cell studies administered to HF patients, focusing mainly on MSCs. It examines the issues surrounding autologous vs. allogenic stem cells, the results of different routes of administration, and implications deriving from the belief that for stem cells to be effective, they must engraft in the myocardium and exert local effects. Since intravenous administration of stem cells leads to sparse cardiac engraftment, stem cell delivery strategies have uniformly involved catheter-based delivery systems. This becomes problematic in a disease that will almost certainly require delivery of the therapeutic throughout the course of the disease. Importantly, it appears that a critical contributing cause of the progressive cardiac dysfunction experienced by HF patients is the existence of a persistent inflammatory response. Since MSCs exert potent anti-inflammatory effects through paracrine mechanisms, it is possible that intravenous delivery of MSCs may be therapeutically effective. If this concept is valid, it could lead to a transformational change in stem cell delivery strategies.

DNA methylation patterns associated with oxidative stress in an ageing population

Background

Oxidative stress has been related to type 2 diabetes (T2D) and cardiovascular disease (CVD), the leading global cause of death. Contributions of environmental factors such as oxidative stress on complex traits and disease may be partly mediated through changes in epigenetic marks (e.g. DNA methylation). Studies relating differential methylation with intermediate phenotypes and disease endpoints may be useful in identifying additional candidate genes and mechanisms involved in disease.

Methods

To investigate the role of epigenetic variation in oxidative stress marker levels and subsequent development of CVD and T2D, we performed analyses of genome-wide DNA methylation in blood, ten markers of oxidative stress (total glutathione [TGSH], reduced glutathione [GSH], oxidised glutathione [GSSG], GSSG to GSH ratio, homocysteine [HCY], oxidised low-density lipoprotein (oxLDL), antibodies against oxLDL [OLAB], conjugated dienes [CD], baseline conjugated dienes [BCD]-LDL and total antioxidant capacity [TAOC]) and incident disease in up to 966 age-matched individuals.

Results

In total, we found 66 cytosine-guanine (CpG) sites associated with one or more oxidative stress markers (false discovery rate [FDR] <0.05). These sites were enriched in regulatory regions of the genome. Genes annotated to CpG sites showed enrichment in annotation clusters relating to phospho-metabolism and proteins with pleckstrin domains. We investigated the contribution of oxidative stress-associated CpGs to development of cardiometabolic disease. Methylation variation at CpGs in the 3'-UTR of HIST1H4D (cg08170869; histone cluster 1, H4d) and in the body of DVL1 (cg03465880; dishevelled-1) were associated with incident T2D events during 10 years of follow-up (all permutation p-values <0.01), indicating a role of epigenetic regulation in oxidative stress processes leading to development or progression of diabetes. Methylation QTL (meQTL) analysis showed significant associations with genetic sequence variants in cis at 28 (42%) of oxidative stress phenotype-associated sites (FDR < 0.05). Integrating cis-meQTLs with genotype-phenotype associations indicated that genetic effects on oxidative stress phenotype at one locus (cg07547695; BCL2L11) may be mediated through DNA methylation.

Conclusions

In conclusion, we report novel associations of DNA methylation with oxidative stress, some of which also show evidence of a relation with T2D incidence.

Electronic supplementary material

The online version of this article (doi:10.1186/s12920-016-0235-0) contains supplementary material, which is available to authorized users.

[Total cholesterol levels predict in-hospital mortality in patients with acute heart failure aged 70 years or older]

INTRODUCTION AND PURPOSE

Lower total cholesterol (TC) levels have been associated with increased mortality In both acute and chronic heart failure (HF) patients. The present study sought to evaluate the impact of TC levels on in-hospital mortality in patients with acute HF aged 70 years or older.

METHODS

Patients were divided into 3 groups based on TC (mg/dL) quartiles (Q) as follow: Q1 (CT≤125), Q2-Q3 (CT 126-174), Q4 (CT≥175). Multivariate logistic regression analysis was performed to assess the association of each variable with hypocholesterolaemia and in-hospital mortality.

RESULTS

The analysis included 301 patients with acute HF. The mean age was 79.3±5.5 years, and 51.2% of patients had HF with depressed systolic function, and the most frequent aetiology was ischaemic heart disease (40.9%). Higher C-reactive protein levels, lower levels of serum albumin and haemoglobin, and lower left ventricle ejection fraction were independently associated with hypocholesterolaemia. There 26 deaths (8.6% of the series) during hospitalization. In-hospital mortality decreased in a stepwise fashion with increasing quartile of TC: Q1 14.3%, Q2-Q3 8.7% and Q4 2.7% (P=.04), and was independently associated with higher serum creatinine levels and lower serum albumin and TC levels.

CONCLUSIONS

Lower TC levels independently predict increased in-hospital mortality risk in older patients with acute HF. A higher inflammatory activity, associated with a lower total cholesterol in this clinical setting may explain the inverse relationship between cholesterol and mortality.

Epidemiology and pathogenesis of diffuse obstructive coronary artery disease: the role of arterial stiffness, shear stress, monocyte subsets and circulating microparticles

Despite falling age-adjusted mortality rates coronary artery disease (CAD) remains the leading cause of death worldwide. Advanced diffuse CAD is becoming an important entity of modern cardiology as more patients with historical revascularisation no longer have suitable anatomy for additional procedures. Advances in the treatment of diffuse obstructive CAD are hampered by a poor understanding of its development. Although the likelihood of developing clinically significant (obstructive) CAD is linked to traditional risk factors, the morphology of obstructive CAD among individuals is highly variable - some patients have diffuse stenotic disease, while others have a focal stenosis. This is challenging to explain in mechanistic terms as vascular endothelium is equally exposed to injury stimulants. Patients with diffuse disease are at high risk of adverse outcomes, particularly if unsuitable for revascularisation. We searched multiple electronic databases (MEDLINE, EMBASE and the Cochrane Database) and reviewed the epidemiology, pathogenesis and prognosis relating to advanced diffuse CAD with particular focus on the role of endothelial shear stress, large artery stiffness, monocyte subsets and circulating microparticles. Key messages Although traditional CAD risk factors correlate strongly with disease severity, significant individual variation in disease morphology exists. Advanced, diffuse CAD is difficult to treat effectively and can significantly impair quality of life and increases mortality. The pathophysiology associated with the progression of CAD is the result of complex maladaptive interaction between the endothelium, cells of the immune system and patterns of blood flow.

Evaluation of Innate Immunity Biomarkers on Admission and at Discharge From an Acute Heart Failure Episode

BACKGROUND

The involvement of the immune system in heart failure (HF) has been demonstrated. Evidence shows that innate immunity can have a role in the remodeling process and progression of HF. With previous studies showing the prognostic value of some innate immunity markers and their relevance in this condition, we aim to evaluate how these markers vary on hospitalization due to an acute episode of HF and at discharge.

METHODS

About 154 patients admitted with acute HF were prospectively recruited. Patients were evaluated on admission and at discharge from the hospital. Patients with infection were separately analyzed. Innate immunity, inflammatory, and cardiac biomarkers were measured and were compared between groups and between admission and discharge and with reference values of biological variation.

RESULTS

Median patients' age was 78 years, and half of the patients were men. The median duration of hospitalization was 6 days. C3 and C4 protein levels significantly increased (P < 0.001) between admission and discharge, as well as eosinophils (P < 0.001) and BNP levels decreased (P < 0.001). Variation in all these variables was independent of infection and biological variation.

CONCLUSION

Our results show that innate immunity markers such as C3 and C4 increase after treatment for acute HF, supporting the hypothesis that they can be involved in the resolution of the acute episode.

Transcriptome Analysis on Monocytes from Patients with Neovascular Age-Related Macular Degeneration

Mononuclear phagocytes (MPs), including monocytes/macrophages, play complex roles in age-related macular degeneration (AMD) pathogenesis. We reported altered gene-expression signature in peripheral blood mononuclear cells from AMD patients, and a chemokine receptor signature on AMD monocytes. To obtain comprehensive understanding of MP involvement, particularly in peripheral circulation in AMD, we performed global gene expression analysis in monocytes. We separated monocytes from treatment-naïve neovascular AMD (nvAMD) patients (n = 14) and age-matched controls (n = 15), and performed microarray and bioinformatics analysis. Quantitative real-time PCR was performed on other sets of nvAMD (n = 25), atrophic AMD (n = 21), and controls (n = 28) for validation. This validated microarray genes (like TMEM176A/B and FOSB) tested, including differences between nvAMD and atrophic AMD. We identified 2,165 differentially-expressed genes (P < 0.05), including 79 genes with log2 fold change ≥1.5 between nvAMD and controls. Functional annotation using DAVID and TANGO demonstrated immune response alterations in AMD monocytes (FDR-P <0.05), validated by randomized data comparison (P < 0.0001). GSEA, ISMARA, and MEME analysis found immune enrichment and specific involved microRNAs. Enrichment of differentially-expressed genes in monocytes was found in retina via SAGE data-mining. These genes were enriched in non-classical vs. classical monocyte subsets (P < 0.05). Therefore, global gene expression analysis in AMD monocytes reveals an altered immune-related signature, further implicating systemic MP activation in AMD.

Roles of inflammation and apoptosis in experimental brain death-induced right ventricular failure

BACKGROUND

Right ventricular (RV) dysfunction remains the leading cause of early death after cardiac transplantation. Methylprednisolone is used to improve graft quality; however, evidence for that remains empirical. We sought to determine whether methylprednisolone, acting on inflammation and apoptosis, might prevent brain death-induced RV dysfunction.

METHODS

After randomization to placebo (n = 11) or to methylprednisolone (n = 8; 15 mg/kg), 19 pigs were assigned to a brain-death procedure. The animals underwent hemodynamic evaluation at 1 and 5 hours after Cushing reflex (i.e., hypertension and bradycardia). The animals euthanized, and myocardial tissue was sampled. This was repeated in a control group (n = 8).

RESULTS

At 5 hours after the Cushing reflex, brain death resulted in increased pulmonary artery pressure (27 ± 2 vs 18 ± 1 mm Hg) and in a 30% decreased ratio of end-systolic to pulmonary arterial elastances (Ees/Ea). Cardiac output and right atrial pressure did not change. This was prevented by methylprednisolone. Brain death-induced RV dysfunction was associated with increased RV expression of heme oxygenase-1, interleukin (IL)-6, IL-10, IL-1β, tumor necrosis factor (TNF)-α, IL-1 receptor-like (ST)-2, signal transducer and activator of transcription-3, intercellular adhesion molecules-1 and -2, vascular cell adhesion molecule-1, and neutrophil infiltration, whereas IL-33 expression decreased. RV apoptosis was confirmed by terminal deoxynucleotide transferase-mediated deoxy uridine triphosphate nick-end labeling staining. Methylprednisolone pre-treatment prevented RV-arterial uncoupling and decreased RV expression of TNF-α, IL-1 receptor-like-2, intercellular adhesion molecule-1, vascular cell adhesion molecule-1, and neutrophil infiltration. RV Ees/Ea was inversely correlated to RV TNF-α and IL-6 expression.

CONCLUSIONS

Brain death-induced RV dysfunction is associated with RV activation of inflammation and apoptosis and is partly limited by methylprednisolone.

Pentoxifylline Attenuates Cardiac Remodeling Induced by Tobacco Smoke Exposure

Background

Tobacco smoke exposure is an important risk factor for cardiac remodeling. Under this condition, inflammation, oxidative stress, energy metabolism abnormalities, apoptosis, and hypertrophy are present. Pentoxifylline has anti‑inflammatory, anti-apoptotic, anti-thrombotic and anti-proliferative properties.

Objective

The present study tested the hypothesis that pentoxifylline would attenuate cardiac remodeling induced by smoking.

Methods

Wistar rats were distributed in four groups: Control (C), Pentoxifylline (PX), Tobacco Smoke (TS), and PX-TS. After two months, echocardiography, invasive blood pressure measurement, biochemical, and histological studies were performed. The groups were compared by two-way ANOVA with a significance level of 5%.

Results

TS increased left atrium diameter and area, which was attenuated by PX. In the isolated heart study, TS lowered the positive derivate (+dp/dt), and this was attenuated by PX. The antioxidants enzyme superoxide dismutase and glutathione peroxidase were decreased in the TS group; PX recovered these activities. TS increased lactate dehydrogenase (LDH) and decreased 3-hydroxyacyl Coenzyme A dehydrogenases (OH-DHA) and citrate synthase (CS). PX attenuated LDH, 3-OH-DHA and CS alterations in TS-PX group. TS increased IL-10, ICAM-1, and caspase-3. PX did not influence these variables.

Conclusion

TS induced cardiac remodeling, associated with increased inflammation, oxidative stress, apoptosis, and changed energy metabolism. PX attenuated cardiac remodeling by reducing oxidative stress and improving cardiac bioenergetics, but did not act upon cardiac cytokines and apoptosis.

Monocyte and macrophage contributions to cardiac remodeling

The mammalian heart contains a population of resident macrophages that expands in response to myocardial infarction and hemodynamic stress. This expansion occurs likely through both local macrophage proliferation and monocyte recruitment. Given the role of macrophages in tissue remodeling, their contribution to adaptive processes in the heart is conceivable but currently poorly understood. In this review, we discuss monocyte and macrophage heterogeneity associated with cardiac stress, the cell's potential contribution to the pathogenesis of cardiac fibrosis, and describe different tools to study and characterize these innate immune cells. Finally, we highlight their potential role as therapeutic targets.

Monocytes increase human cardiac myofibroblast-mediated extracellular matrix remodeling through TGF-β1

Following myocardial infarction (MI), cardiac myofibroblasts remodel the extracellular matrix (ECM), preventing mechanical complications. However, prolonged myofibroblast activity leads to dysregulation of the ECM, maladaptive remodeling, fibrosis, and heart failure (HF). Chronic inflammation is believed to drive persistent myofibroblast activity; however, the mechanisms are unclear. We assessed the influence of peripheral blood monocytes on human cardiac myofibroblast activity in a three-dimensional (3D) ECM microenvironment. Human cardiac myofibroblasts isolated from surgical biopsies of the right atrium and left ventricle were seeded into 3D collagen matrices. Peripheral blood monocytes were isolated from healthy human donors and cocultured with myofibroblasts. Monocytes increased myofibroblast activity measured by collagen gel contraction (baseline: 57.6 ± 5.9% vs. coculture: 65.2 ± 7.1% contraction; P < 0.01) and increased local ECM remodeling quantified by confocal microscopy. Under coculture conditions that allow indirect cellular interaction via paracrine factors but prevent direct cell-cell contact, monocytes had minimal effects on myofibroblast activity (17.9 ± 11.1% vs. 6.4 ± 7.0% increase, respectively; P < 0.01). When cells were cultured under direct contact conditions, multiplex analysis of the coculture media revealed an increase in the paracrine factors TGF-β1 and matrix metalloproteinase 9 compared with baseline (122.9 ± 10.1 pg/ml and 3,496.0 ± 190.4 pg/ml, respectively, vs. 21.5 ± 16.3 pg/ml and 183.3 ± 43.9 pg/ml; P < 0.001). TGF-β blockade abolished the monocyte-induced increase in cardiac myofibroblast activity. These data suggest that direct cell-cell interaction between monocytes and cardiac myofibroblasts stimulates TGF-β-mediated myofibroblast activity and increases remodeling of local matrix. Peripheral blood monocyte interaction with human cardiac myofibroblasts stimulates myofibroblast activity through release of TGF-β1. These data implicate inflammation as a potential driver of cardiac fibrosis.

A Central Role for Monocyte-Platelet Interactions in Heart Failure

Heart failure (HF) is an increasingly prevalent and costly multifactorial syndrome with high morbidity and mortality rates. The exact pathophysiological mechanisms leading to the development of HF are not completely understood. Several emerging paradigms implicate cardiometabolic risk factors, inflammation, endothelial dysfunction, myocardial fibrosis, and myocyte dysfunction as key factors in the gradual progression from a healthy state to HF. Inflammation is now a recognized factor in disease progression in HF and a therapeutic target. Furthermore, the monocyte-platelet interaction has been highlighted as an important pathophysiological link between inflammation, thrombosis, endothelial activation, and myocardial malfunction. The contribution of monocytes and platelets to acute cardiovascular injury and acute HF is well established. However, their role and interaction in the pathogenesis of chronic HF are not well understood. In particular, the cross talk between monocytes and platelets in the peripheral circulation and in the vicinity of the vascular wall in the form of monocyte-platelet complexes (MPCs) may be a crucial element, which influences the pathophysiology and progression of chronic heart disease and HF. In this review, we discuss the role of monocytes and platelets as key mediators of cardiovascular inflammation in HF, the mechanisms of cell activation, and the importance of monocyte-platelet interaction and complexes in HF pathogenesis. Finally, we summarize recent information on pharmacological inhibition of inflammation and studies of antithrombotic strategies in the setting of HF that can inform opportunities for future work. We discuss recent data on monocyte-platelet interactions and the potential benefits of therapy directed at MPCs, particularly in the setting of HF with preserved ejection fraction.

Monocyte and macrophage subsets along the continuum to heart failure: Misguided heroes or targetable villains?

The important contribution of monocytes and macrophages to cardiovascular disease and heart failure pathophysiology has attracted significant attention in the past several years. Moreover, subsets of these cells have been shown to partake in the initiation and exacerbation of several cardiovascular pathologies including atherosclerosis, myocardial infarction, pressure overload, cardiac ischemia and fibrosis. This review focuses on the role of monocytes and macrophages along the continuum to heart failure and the contribution of different cell subsets in promoting or inhibiting cardiac injury or repair. It outlines a primary role for the monocyte/macrophage system as an important regulator of cardiac inflammation and extracellular matrix remodelling in early and late stage heart disease with particular focus on phenotypic plasticity and the inflammatory and fibrotic functions of these cells. It also summarizes evidence from pre-clinical and clinical studies evaluating monocyte type regulation and its functional significance for development of cardiovascular disease and heart failure. Finally, current and prospective therapeutic approaches based on monocyte and macrophage manipulation for the treatment of cardiovascular disease and heart failure are discussed. Based on these data, future work in this fertile research area may aid in identifying potential diagnostic biomarkers and novel therapies for chronic heart failure.

Efficacy of mineralocorticoid receptor antagonism in the acute myocardial infarction phase: eplerenone versus spironolactone

AIMS

The selective mineralocorticoid receptor (MR) antagonist eplerenone given early in patients with acute myocardial infarction (MI) improves clinical outcome, whereas little is known about the effectiveness of early spironolactone therapy. We aimed to compare the ability of eplerenone and spironolactone to promote cardiac repair after experimental MI.

METHODS AND RESULTS

Starting immediately after coronary artery ligation, C57BL/6J mice were treated with placebo, eplerenone, or spironolactone. At 7 days, treatment with eplerenone or spironolactone reduced thinning and expansion of healing infarct and improved early left ventricular chamber enlargement. Remarkably, eplerenone therapy resulted in significantly greater improvement than spironolactone of left ventricular contractile function and relaxation, associated with a more considerable leftward and downward shift of the pressure volume curve. Seven-day survival rate was significantly increased only in eplerenone treated mice. Moreover, eplerenone was superior to spironolactone in ameliorating neovessel formation in the injured myocardium. Optimized flow cytometry analysis of the monocyte differentiation marker Ly6C revealed predominant accumulation of Ly6Chigh monocytes/macrophages at the site of ischemic injury during the early inflammatory phase in placebo-treated mice. In contrast, MR antagonism, especially by eplerenone, led to a skewing of the monocyte/macrophage population toward a higher frequency of healing promoting Ly6Clow cells.

CONCLUSION

The MR antagonist eplerenone versus spironolactone showed superior efficacy during the acute MI phase with more beneficial effects on survival, early cardiac dilation, and functional decline. Modulation of monocyte maturation and enhanced infarct neovessel formation appears to play a pivotal role.

Up-regulated TLR4 in cardiomyocytes exacerbates heart failure after long-term myocardial infarction

It remains unclear whether and how cardiomyocytes contribute to the inflammation in chronic heart failure (CHF). We recently reviewed the capacity of cardiomyocytes to initiate inflammation, by means of expressing certain immune receptors such as toll‐like receptors (TLRs) that respond to pathogen‐ and damage‐associated molecular patterns (PAMP and DAMP). Previous studies observed TLR4‐mediated inflammation within days of myocardial infarction (MI). This study examined TLR4 expression and function in cardiomyocytes of failing hearts after 4 weeks of MI in rats. The increases of TLR4 mRNA and proteins, as well as inflammatory cytokine production, were observed in both the infarct and remote myocardium. Enhanced immunostaining for TLR4 was observed in cardiomyocytes but not infiltrating leucocytes. The injection of lentivirus shRNA against TLR4 into the infarcted heart decreased inflammatory cytokine production and improved heart function in vivo. Accordingly, in cardiomyocytes isolated from CHF hearts, increases of TLR4 mRNA and proteins were detected. More robust binding of TLR4 with lipopolysaccharide (LPS), a PAMP ligand for TLR4, and heat shock protein 60 (HSP60), a DAMP ligand for TLR4, was observed in CHF cardiomyocytes under a confocal microscope. The maximum binding capacity (B_max) of TLR4 was increased for LPS and HSP60, whereas the binding affinity (Kd) was not significantly changed. Furthermore, both LPS and HSP60 induced more robust production of inflammatory cytokines in CHF cardiomyocytes, which was reduced by TLR4‐blocking antibodies. We conclude that the expression, ligand‐binding capacity and pro‐inflammatory function of cardiomyocyte TLR4 are up‐regulated after long‐term MI, which promote inflammation and exacerbate heart failure.