Inflammatory mediators in heart failure

Quercetin and Its Derivative Counteract Palmitate-Dependent Lipotoxicity by Inhibiting Oxidative Stress and Inflammation in Cardiomyocytes

Cardiac lipotoxicity plays an important role in the pathogenesis of obesity-related cardiovascular disease. The flavonoid quercetin (QUE), a nutraceutical compound that is abundant in the "Mediterranean diet", has been shown to be a potential therapeutic agent in cardiac and metabolic diseases. Here, we investigated the beneficial role of QUE and its derivative Q2, which demonstrates improved bioavailability and chemical stability, in cardiac lipotoxicity. To this end, H9c2 cardiomyocytes were pre-treated with QUE or Q2 and then exposed to palmitate (PA) to recapitulate the cardiac lipotoxicity occurring in obesity. Our results showed that both QUE and Q2 significantly attenuated PA-dependent cell death, although QUE was effective at a lower concentration (50 nM) when compared with Q2 (250 nM). QUE decreased the release of lactate dehydrogenase (LDH), an important indicator of cytotoxicity, and the accumulation of intracellular lipid droplets triggered by PA. On the other hand, QUE protected cardiomyocytes from PA-induced oxidative stress by counteracting the formation of malondialdehyde (MDA) and protein carbonyl groups (which are indicators of lipid peroxidation and protein oxidation, respectively) and intracellular ROS generation, and by improving the enzymatic activities of catalase and superoxide dismutase (SOD). Pre-treatment with QUE also significantly attenuated the inflammatory response induced by PA by reducing the release of key proinflammatory cytokines (IL-1β and TNF-α). Similar to QUE, Q2 (250 nM) also significantly counteracted the PA-provoked increase in intracellular lipid droplets, LDH, and MDA, improving SOD activity and decreasing the release of IL-1β and TNF-α. These results suggest that QUE and Q2 could be considered potential therapeutics for the treatment of the cardiac lipotoxicity that occurs in obesity and metabolic diseases.

Inhibition of protein kinase R protects against palmitic acid-induced inflammation, oxidative stress, and apoptosis through the JNK/NF-kB/NLRP3 pathway in cultured H9C2 cardiomyocytes

BACKGROUND AND PURPOSE

Double-stranded RNA-dependent protein kinase (PKR) is a critical regulator of apoptosis, oxidative stress, and inflammation under hyperlipidemic and insulin resistance conditions. Saturated free fatty acids, such as palmitic acid (PA), are known inducers of apoptosis in numerous cell types. However, the underlying molecular mechanism is not fully understood. The aim of the present study was to examine the effect of PA on cultured rat H9C2 cardiac myocytes cells and to investigate the PKR mediated harmful effects of PA in vitro in cultured cardiomyocytes.

EXPERIMENTAL APPROACH

PKR expression was determined by immunofluorescence and immunoblotting. Oxidative stress and apoptosis were determined by flow cytometry and assay kits. The expression of different gene markers of apoptosis, oxidative stress, and inflammation were measured by Western blot analysis and reverse transcription polymerase chain reaction.

KEY RESULTS

PKR expression, reactive oxygen species levels as well as apoptosis were increased in PA-treated cultured H9C2 cardiomyocytes. The harmful effects of PA were attenuated by a selective PKR inhibitor, C16. Moreover, we observed that upregulation of c-Jun N-terminal kinase (JNK), nuclear factor-kB (NF-kB) and NACHT, LRR and PYD domains-containing protein 3 (NLRP3) pathways is associated with increased expression of interleukin 6 and tumor necrosis factor-α in PA-treated cardiomyocytes and attenuation by a selective PKR inhibitor.

CONCLUSION AND IMPLICATIONS

Our study reports, for the first time, that PKR-mediated harmful effects of PA in cultured cardiomyocytes via activation of JNK, NF-kB, and NLRP3 pathways. Inhibition of PKR is one of the possible mechanistic approaches to inhibit inflammation, oxidative stress, and apoptosis in lipotoxicity-induced cardiomyocyte damage.

Experimental Evidences Supporting the Benefits of Exercise Training in Heart Failure

Heart Failure (HF), a common end point for many cardiovascular diseases, is a syndrome with a very poor prognosis. Although clinical trials in HF have achieved important outcomes in reducing mortality, little is known about functional mechanisms conditioning health improvement in HF patients. In parallel with clinical studies, basic science has been providing important discoveries to understand the mechanisms underlying the pathophysiology of HF, as well as to identify potential targets for the treatment of this syndrome. In spite of being the end-point of cardiovascular derangements caused by different etiologies, autonomic dysfunction, sympathetic hyperactivity, oxidative stress, inflammation and hormonal activation are common factors involved in the progression of this syndrome. Together these causal factors create a closed link between three important organs: brain, heart and the skeletal muscle. In the past few years, we and other groups have studied the beneficial effects of aerobic exercise training as a safe therapy to avoid the progression of HF. As summarized in this chapter, exercise training, a non-pharmacological tool without side effects, corrects most of the HF-induced neurohormonal and local dysfunctions within the brain, heart and skeletal muscles. These adaptive responses reverse oxidative stress, reduce inflammation, ameliorate neurohormonal control and improve both cardiovascular and skeletal muscle function, thus increasing the quality of life and reducing patients' morbimortality.

Aerobic Exercise and Pharmacological Therapies for Skeletal Myopathy in Heart Failure: Similarities and Differences

Skeletal myopathy has been identified as a major comorbidity of heart failure (HF) affecting up to 20% of ambulatory patients leading to shortness of breath, early fatigue, and exercise intolerance. Neurohumoral blockade, through the inhibition of renin angiotensin aldosterone system (RAS) and β-adrenergic receptor blockade (β-blockers), is a mandatory pharmacological therapy of HF since it reduces symptoms, mortality, and sudden death. However, the effect of these drugs on skeletal myopathy needs to be clarified, since exercise intolerance remains in HF patients optimized with β-blockers and inhibitors of RAS. Aerobic exercise training (AET) is efficient in counteracting skeletal myopathy and in improving functional capacity and quality of life. Indeed, AET has beneficial effects on failing heart itself despite being of less magnitude compared with neurohumoral blockade. In this way, AET should be implemented in the care standards, together with pharmacological therapies. Since both neurohumoral inhibition and AET have a direct and/or indirect impact on skeletal muscle, this review aims to provide an overview of the isolated effects of these therapeutic approaches in counteracting skeletal myopathy in HF. The similarities and dissimilarities of neurohumoral inhibition and AET therapies are also discussed to identify potential advantageous effects of these combined therapies for treating HF.

Cardiac dysfunction in cirrhosis - does adrenal function play a role? A hypothesis

Cirrhotic cardiomyopathy (CCM), a condition of unknown pathogenesis, is characterized by suboptimal ventricular contractile response to stress, diastolic dysfunction and QT interval prolongation. It is most often found in patients with advanced cirrhosis. It is clinically relevant during stressful conditions, such as sepsis, bleeding and surgery. CCM reverses after liver transplantation and potentially has a role in the pathogenesis of hepatorenal syndrome. In adrenal insufficiency (AI), cardiac dysfunction is a feature with low ejection fraction, decreased left ventricular chamber size and electrocardiographic abnormalities, including QT interval prolongation. With optimal diagnostic tests, AI is present in approximately 10% of patients with cirrhosis, particularly in those with advanced disease. Down-regulation and decreased number of beta-adrenergic receptors, and high catecholamine levels are common to both cardiac conditions. Thus, AI may play a role in CCM. Steroid replacement therapy reverses cardiac changes in AI, and may do so for CCM, with important therapeutic implications; this needs formal evaluation.

PKCβII inhibition attenuates myocardial infarction induced heart failure and is associated with a reduction of fibrosis and pro-inflammatory responses

Protein kinase C βII (PKCβII) levels increase in the myocardium of patients with end-stage heart failure (HF). Also targeted overexpression of PKCβII in the myocardium of mice leads to dilated cardiomyopathy associated with inflammation, fibrosis and myocardial dysfunction. These reports suggest a deleterious role of PKCβII in HF development. Using a post-myocardial infarction (MI) model of HF in rats, we determined the benefit of chronic inhibition of PKCβII on the progression of HF over a period of 6 weeks after the onset of symptoms and the cellular basis for these effects. Four weeks after MI, rats with HF signs that were treated for 6 weeks with the PKCβII selective inhibitor (βIIV5-3 conjugated to TAT(47-57) carrier peptide) (3 mg/kg/day) showed improved fractional shortening (from 21% to 35%) compared to control (TAT(47-57) carrier peptide alone). Formalin-fixed mid-ventricle tissue sections stained with picrosirius red, haematoxylin and eosin and toluidine blue dyes exhibited a 150% decrease in collagen deposition, a two-fold decrease in inflammation and a 30% reduction in mast cell degranulation, respectively, in rat hearts treated with the selective PKCβII inhibitor. Further, a 90% decrease in active TGFβ1 and a significant reduction in SMAD2/3 phosphorylation indicated that the selective inhibition of PKCβII attenuates cardiac remodelling mediated by the TGF-SMAD signalling pathway. Therefore, sustained selective inhibition of PKCβII in a post-MI HF rat model improves cardiac function and is associated with inhibition of pathological myocardial remodelling.

Modification of a volume-overload heart failure model to track myocardial remodeling and device-related reverse remodeling

Purpose. To provide an ovine model of ventricular remodeling and reverse remodeling by creating congestive heart failure (CHF) and then treating it by implanting a left ventricular assist device (LVAD). Methods. We induced volume-overload heart failure in 2 sheep; 20 weeks later, we implanted an LVAD and assessed recovery 11 weeks thereafter. We examined changes in histologic and hemodynamic data and levels of cellular markers of CHF. Results. After CHF induction, we found increases in LV end-diastolic pressure, LV systolic and diastolic dimensions, wall thickness, left atrial diameter, and atrial natriuretic protein (ANP) and endothelin-1 (ET-1) levels; β-adrenergic receptor (BAR) and dystrophin expression decreased markedly. Biopsies confirmed LV remodeling. After LVAD support, LV systolic and diastolic dimensions, wall thickness, and mass, and ANP and ET-1 levels decreased. Histopathologic and hemodynamic markers improved, and BAR and dystrophin expression normalized. Conclusions. We describe a successful sheep model for ventricular and reverse remodeling.

The effect of physical training on systemic proinflammatory cytokine expression in heart failure patients: a systematic review

Systemic inflammation is associated with cardiovascular disease, especially the end stages of heart failure (HF). The authors sought to determine by systematic review whether physical therapy reduces serum levels of pro-inflammatory cytokines in HF patients. Potential studies were identified from a systematic search of Medline (Ovid) (1950-October 2010), Embase.com (1974-current), Cochrane Central Register of Controlled Trials, CINAHL (1981-current), and Web of Science (2000-current). The search strategy included a mix of MeSH and free text terms for key concepts. A total of 11 studies were included, with 4 reporting a post-training reduction in tumor necrosis factor α (TNF-α), of which 3 used traditional aerobic or resistance exercise and 1 used functional electrical stimulation. Reduced post-training serum levels of interleukin 6 were reported by one exercise study. The one study that employed combined resistance and aerobic training only showed soluble receptors TNF-α1 and TNF-α2 to be lower. The one study of respiratory muscle training and two studies that employed electrical stimulation had limited effect on cytokines and peak maximal oxygen uptake. With the exception of one study, those therapies that employed ≥ 5 sessions per week lowered serum TNF-α. Our review data suggest that physical therapies employing ≥ 5 sessions per week are most likely to reduce serum levels of TNF-α in HF patients. No isolated study of resistance training has yet examined the relationship between muscle wasting, glycogen depletion, and the ability of exercise training to reverse both of these conditions in HF patients.

Effect of exercise training on interleukin-6, tumour necrosis factor alpha and functional capacity in heart failure

Background. We pooled data from four studies, to establish whether exercise training programs were able to modulate systemic cytokine levels of tumour necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6). A second aim was to establish if differences in ExT regimens are related to degree of change in cytokines and peak VO₂. Methods. Data from four centres relating to training protocol, exercise capacity, and cytokine measures (TNF-alpha and IL-6) were pooled for analysis. Results. Data for 106 CHF patients were collated (98 men, age 62 ± 10 yrs, wt 79 ± 14 Kg). Patients were moderately impaired (peak VO₂ 16.9 ± 4.4 mls/kg/min), with moderate LV systolic dysfunction (EF 30 ± 6.9%), 78% (83) had ischaemic cardiomyopathy. After ExT, peak VO₂ increased 1.4 ± 3.4 ml/kg/min (P < .001), serum TNF-alpha decreased 1.9 ± 8.6 pg/ml (P = .02) and IL-6 was not significantly changed (0.5 ± 5.4 pg/ml, P = .32) for the whole group. Baseline and post-training peak VO₂ changes were not correlated with change in cytokine levels. Conclusions. Exercise training reduces levels TNF-alpha but not IL-6 in CHF. However, across a heterogenic patient group, change in peak VO₂ was not correlated with alterations in cytokine levels. While greater exercise volume (hours) was superior in improving peak VO₂, no particular characteristic of ExT regimes appeared superior in effecting change in serum cytokines.

IL-6 loss causes ventricular dysfunction, fibrosis, reduced capillary density, and dramatically alters the cell populations of the developing and adult heart

Interleukin-6 (IL-6) is a pleiotropic cytokine responsible for many different processes including the regulation of cell growth, apoptosis, differentiation, and survival in various cell types and organs, including the heart. Recent studies have indicated that IL-6 is a critical component in the cell-cell communication between myocytes and cardiac fibroblasts. In this study, we examined the effects of IL-6 deficiency on the cardiac cell populations, cardiac function, and interactions between the cells of the heart, specifically cardiac fibroblasts and myocytes. To examine the effects of IL-6 loss on cardiac function, we used the IL-6(-/-) mouse. IL-6 deficiency caused severe cardiac dilatation, increased accumulation of interstitial collagen, and altered expression of the adhesion protein periostin. In addition, flow cytometric analyses demonstrated dramatic alterations in the cardiac cell populations of IL-6(-/-) mice compared with wild-type littermates. We observed a marked increase in the cardiac fibroblast population in IL-6(-/-) mice, whereas a concomitant decrease was observed in the other cardiac cell populations examined. Moreover, we observed increased cell proliferation and apoptosis in the developing IL-6(-/-) heart. Additionally, we observed a significant decrease in the capillary density of IL-6(-/-) hearts. To elucidate the role of IL-6 in the interactions between cardiac fibroblasts and myocytes, we performed in vitro studies and demonstrated that IL-6 deficiency attenuated the activation of the STAT3 pathway and VEGF production. Taken together, these data demonstrate that a loss of IL-6 causes cardiac dysfunction by shifting the cardiac cell populations, altering the extracellular matrix, and disrupting critical cell-cell interactions.

Neurohumoral changes in chronic heart failure

BACKGROUND

Humoral systems play an important role in the pathophysiology and development of chronic heart failure (CHF).

METHODS

We conducted a search of neurohumoral activation in heart failure and its risk in the development of CHF.

RESULTS AND CONCLUSION

Neurohumoral factors may be divided into vasoconstrictive, vasodilative and cytokines. The main vasoconstrictive systems are the renin-angiotensin-aldosterone system (RAAS) and the sympathoadrenal system (SAS). Cytokines include tumour necrosis factor (TNF) alpha and interleukins. The systems of actions are interconnected and they mutually influence their secretion and activities. The possibilities of their detection and assessment for clinical purposes depend on their changes and kinetics in the organism and on the activity of individual metabolites. Apart from their vasoactive effects, the majority of humoral actions also interfere in the process of remodelling, function of the endothelium, blood elements, cardiomyocytes, cells of the smooth muscles, and in immunity as well as inflammatory processes. The rapid development of knowledge on the humoral actions in recent years has made possible their utilisation in diagnostics, treatment and prognosis.

Genetics of humoral and cytokine activation in heart failure and its importance for risk stratification of patients

The study objective is to prove an association among plasma concentration of big endothelin and endothelin-1, other clinical parameters and two frequent polymorphisms - G8002A and -3A/-4A - in the endothelin-1 (EDN-1) coding gene (6p21-23), and among plasma concentration of TNF alpha and gene polymorphisms TNF alpha -308 A/G, -238 A/G, TNF beta Ncol and 3'TACE (tumour necrosis factor alpha converting enzyme) in patients with chronic heart failure (CHF). The second objective is to find an association between polymorphisms G8002A and -3A/4A EDN-1 with diabetes mellitus (DM), peripheral artery disease (PAD) and myocardial infarction (MI) in patients with chronic heart failure (CHF). The study population included 266 patients with symptomatic CHF and proven dysfunction of the left ventricle (LV). Genotyping and plasma concentrations of humoral substances were examined in 224 patients with ejection fraction (EF) below 40%. No associations between plasma concentrations of endothelin-1 and big endothelin and polymorphisms G8002A (p=0.87, p=0.81) and -3A/-4A (p=0.871, p=0.749) in the gene coding endothelin-1 were found. No associations were observed between plasma concentration of TNF alpha and genotypes in four polymorphisms in TNF alpha, beta and TACE genes. A significant correlation was seen between plasma concentration of big endothelin and pulmonary congestion. Patients with ischemic heart disease (IHD) and previous MI showed a difference in the distribution of genotype G8002A for endothelin-1: allele G 0.718 and A 0.282 vs those without MI: allele G 0.882 and A 0.118, (p<0.05). Patients with IHD and DM had allele G in 0.67 and A 0.33, while those without DM had allele G in 0.790 and A in 0.209 (p<0.03). Patients with IHD and concomitant PAD had allele G in 0.718 and A in 0.282 vs those without PAD allele G in 0.882 and A in 0.118 (p<0.0004). Patients with dilative cardiomyopathy (DCMP) showed no differences in genotype G8002A and presence of DM or PAD. It might be speculated that in the case of endothelin-1 and TNF alpha in CHF the genetic determination is not important, and plasma concentrations are influenced more by the disease severity. Ischemics with previous MI, concomitant DM or PAD showed more frequently allele A and less often allele G than those without these diseases. A genotype with allele A is associated with higher risk of concomitant diseases.

Anti-Inflammatory Effect of Cardiac Resynchronization Therapy

BACKGROUND

Congestive heart failure (CHF) is associated with persistent immune activation. Medical therapy has been shown to exert only limited anti-inflammatory effects. Cardiac resynchronization therapy (CRT) reduces morbidity and mortality in a subset of patients with heart failure, but it is not known whether this treatment affects the immune system as well. To test this hypothesis, eight patients with heart failure scheduled for CRT were investigated for immune activation before and 6 months after CRT treatment.

METHODS AND RESULTS

After 6 months, all patients had improved in NYHA-class and LVEF, and there was a statistically significant reduction in serum N-terminal pro brain natriuretic peptide (BNP). Furthermore, there was a statistically significant reduction in plasma levels of the chemokines monocyte chemoattractant protein 1 (MCP-1) and interleukin 8 (IL-8) and the cytokine interleukin 6 (IL-6). We observed no changes in the levels of interleukin 1beta (IL-1beta), tumor necrosis factor alpha (TNF-alpha), interleukin 10 (IL-10), or complement activation products. There was a significant correlation between changes in BNP and IL-6 (r = 0.74, P = 0.037).

CONCLUSION

Although based upon a limited number of patients, this report indicates that CRT reduces peripheral markers of immune activation in patients with CHF. Further large scale studies are warranted to verify these findings.

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Interleukin-1 β inhibits Na+-K+ATPase activity and protein expression in cardiac myocytes

Recent studies have shown that heart diseases are always accompanied with high levels of IL-1beta and a decrease in Na+-K+ ATPase concentrations. This work studies the involvement of the cytokine in the observed changes in the pump. Rats were injected intraperitoneally with 400 mg of IL-1beta and 4 h later, the heart was isolated and a crude homogenate of the right and left ventricles was prepared and tested for Na+-K+ ATPase activity and protein expression. IL-1beta inhibited by around 70% the activity of the ATPase in the left and right ventricles. This inhibition of the pump was ascribed to a decrease in its protein expression as demonstrated by western blot analysis. A dose and time response study conducted on isolated cardiac myocytes confirmed the inhibitory role of the cytokine on the ATPase and showed that IL-1beta exerts its maximal down-regulatory effect at 2 h and at a dose of 20 ng/ml. The cytokine caused also an up-regulation of the NaKCl2 cotransporter. Both MEK and p38MAPK were shown to be involved in the signaling pathway activated by the cytokine. It can be concluded that the decrease in the Na+-K+ ATPase concentration observed in heart diseases is a consequence of the accompanying high levels of IL-1beta, and may be responsible for the different symptoms that accompany cardiac ischemia.

Heart failure as a cause for hospitalization in chronic dialysis patients

BACKGROUND

Risk factors for heart failure (HF) have not been reported previously in a nationally representative sample of dialysis patients.

METHODS

We conducted a historic cohort study of 1,995 patients enrolled in the US Renal Data System Dialysis Morbidity and Mortality Study Wave 2 who were Medicare eligible at the study start and were followed up until December 31, 1999, or receipt of a renal transplant. Cox regression analysis was used to model associations with time to first hospitalization for both recurrent and de novo HF (International Classification of Diseases, Ninth Revision code 428.x), defined as patients with and without a history of HF, respectively.

RESULTS

The incidence density of HF was 71/1,000 person-years. Angiotensin-converting enzyme inhibitors and beta-blockers were each used in less than 25% of patients with a known history of HF. A history of coronary heart disease was associated with an increased total risk for HF, as were hemodialysis (versus peritoneal dialysis), aspirin use, and a history of diabetes. However, hemodialysis and aspirin use were the only factors associated with both de novo and recurrent HF. Widened pulse pressure was associated with de novo HF. The mortality rate after HF was 83% at 3 years (adjusted hazard ratio for mortality, 2.10; 95% confidence interval, 1.80 to 2.45; P < 0.0001).

CONCLUSION

In chronic dialysis patients, hemodialysis and aspirin use were associated with increased risk for both total and de novo HF. Hospitalized HF was associated with a significantly increased risk for death.

Systemic consequences of ventricular assist devices: alterations of coagulation, immune function, inflammation, and the neuroendocrine system

Implantable ventricular assist devices have proven efficacious as a bridge to transplantation and as a bridge to recovery. Although current indications for use of assist devices are somewhat limited, they are likely to expand in the upcoming years, including their use as destination therapy for end-stage heart failure. Recipients of assist devices, however, are prone to certain device-specific complications, including excessive postoperative bleeding, late propensity for thromboembolism, infections, and systemic inflammation, which may contribute to end-organ dysfunction. This article reviews the systemic biochemical alterations underlying these clinical phenomena. As assist devices are increasingly used, better understanding of these systemic perturbations is imperative.

Origin of symptoms in patients with cachexia with special reference to weakness and shortness of breath

Cachexia is a complication of many disorders. It is associated with an extremely poor prognosis and many symptoms. The wasting process affects particularly skeletal muscle causing extreme fatigue and weakness. In many underlying conditions associated with cachexia, the patient also suffers an often unexplained severe dyspnoea along with weakness, asthenia and exhaustion. There appears to be marked similarities in the cause of dyspnoea and fatigue between different cachectic conditions. Using the example of cardiac cachexia, this article reviews the evidence linking skeletal muscle reflex inputs to ventilatory control and exaggerated chemoreflex responses as candidates for the heightened perception of dyspnoea which cannot be explained by heart or lung dysfunction in many patients. Evidence is reviewed that similar processes may occur in other cachexias, especially those complicating cancer, AIDS, chronic liver disease, and chronic lung disease. Potential novel therapeutic strategies to combat these cachexia symptoms are reviewed.

Secretion of IL-6, IL-11 and LIF by human cardiomyocytes in primary culture

Interleukin (IL)-6-type cytokines are multifunctional proteins involved in cardiac hypertrophy and myocardial protection. Recent studies, performed on animal models, report the production of these cytokines by heart. The aim of this study was to analyse the capacity of myocytes and fibroblasts isolated from human atrium to secrete IL-6, leukaemia inhibitory factor (LIF), cardiotrophin-1 (CT-1), IL-11, oncostatin M (OSM), ciliary neurotrophic factor (CNTF) and the soluble receptor subunits sIL-6R and sgp130 during primary culture. We detected LIF, IL-11, sgp130 and a large amount of IL-6, but not OSM, CT-1, CNTF nor IL-6R in these culture supernatants. Both cardiomyocytes and fibroblasts are able to spontaneously produce IL-6. The increase of IL-6 production all along the culture period appears to be the consequence of fibroblast proliferation and gp130 stimulation. This is the first demonstration that human cardiac cells are able to secrete IL-6, but also LIF and IL-11 in vitro. These cytokines could be involved in an autocrine and/or a paracrine networks regulating myocardial cyto-protection, hypertrophy and fibrosis.

Diagnostic value of interleukin-1alpha, interleukin-6, and tumor necrosis factor in pleural effusions

STUDY OBJECTIVES

Interleukin (IL)-1alpha, IL-6, and tumor necrosis factor (TNF)-alpha were measured in pleural fluid from 57 patients with pleural effusion in order to evaluate the diagnostic utility of these cytokines. We studied 20 patients with malignant pleural effusion, 11 patients with parapneumonic pleural effusion, 9 patients with tuberculous pleural effusion, and 17 patients with transudative pleural effusion. Cytokines were measured by radioimmunoassay.

SETTING

University tertiary hospital.

RESULTS

The mean values of the three cytokines measured in pleural fluid or in serum were significantly higher in patients with exudates than with transudates (p < 0.05). The ratio of IL-6 in pleural fluid to serum was significantly higher in exudates than in transudates (p < 0.05). The level of IL-6 in pleural fluid was significantly higher in tuberculous than malignant (p < 0.007) or parapneumonic pleural effusions (p < 0.04). No significant difference between the three types of exudates was found in pleural fluid levels of IL-1alpha or TNF-alpha.

CONCLUSIONS

Serum levels of IL-1alpha, TNF-alpha, and in particular IL-6 can distinguish exudates from transudates, while pleural fluid IL-6 levels could be useful as an additional marker in the differential diagnosis of tuberculous, malignant, and parapneumonic exudates. Finally, our results suggest that there is local cytokine production in exudative pleural effusions.

Cirrhotic cardiomyopathy: a pathophysiological review of circulatory dysfunction in liver disease

The systemic circulation in patients with cirrhosis is hyperdynamic with an increased cardiac output and heart rate and a reduced systemic vascular resistance as the most pronounced alterations. The concomitant cardiac dysfunction has recently been termed "cirrhotic cardiomyopathy", which is an entity different from that seen in alcoholic heart muscle disease. Clinically, these patients present with sodium fluid retention and strain often unmasks the presence of latent heart failure. No specific treatment can yet be recommended but caution should be used with respect to procedures that may stress the heart such as shunt implantation and liver transplantation.

When cancer and heart failure cross paths: a case report of severe cardiorenal compromise associated with the anti-CD20 monoclonal antibody rituximab in a patient with dilated cardiomyopathy

The authors describe the case of a 41-year-old man with end-stage, nonischemic dilated cardiomyopathy of 11 years' duration. The patient had been deemed ineligible for transplantation, despite his young age, when he was diagnosed with non-Hodgkin's lymphoma 7 years previously. Since he had survived the lymphoma without significant chemotherapy, while his cardiovascular and renal status continued to deteriorate, the issue was revisited. In an attempt to at least render him eligible for an assist device, a novel, promising, and reportedly nontoxic immunomodulation therapy for his lymphoma was employed. This consisted of infusion of the monoclonal antibody rituximab, specifically targeting the CD20 antigen on B cells. Despite testimonials concerning the benign nature of the treatment, the patient was unable to tolerate it and his clinical condition deteriorated rapidly, eventually leading to his death. The authors discuss potential mechanisms that might have accounted for the patient's cardiorenal compromise, with a focus on a very rare "cytokine release" syndrome attributed to this type of monoclonal antibody therapy and the probable interplay of cytokines in advanced heart failure. (c)2001 CHF, Inc.

Carvedilol in the treatment of chronic heart failure

Along with the angiotensin-converting enzyme inhibitors (ACEIs), the beta-adrenergic receptor blockers have gradually emerged to be standard in the therapy of heart failure. Individual beta-blockers that have been shown to reduce all-cause mortality in patients with heart failure include bisoprolol, metoprolol and carvedilol. Carvedilol distinguishes from the other beta-blockers as being a non-selective beta(1)- and beta(2)-receptor blocker with (1)-receptor blockade effect and anti-oxidant properties. The drug does not have sympathomimetic activity and has vasodilatory effects attributable to its (1)-receptor blockade property. Experimental and clinical studies have confirmed carvedilol's vasodilator, anti-oxidant and anti-apoptotic properties, which may contribute to its effect in reversing cardiac remodelling in animal models and patients with heart failure. These pharmacological properties render carvedilol a potentially useful agent in the treatment of patients with heart failure. Early studies of carvedilol in heart failure have reported beneficial haemodynamic effects but variable effects on exercise tolerance and clinical well being. The large-scale US Carvedilol Heart Failure Program and the Australian/New Zealand Heart Failure Collaborative Research Group reported beneficial effects of carvedilol on mortality, morbidity and clinical well being in patients with mild-to-moderate heart failure. The recently reported but yet unpublished preliminary results of the COPERNICUS study suggest that carvedilol improves mortality and morbidity in patients with advanced heart failure and severe symptoms. At this time, it is unclear whether the ancillary pharmacological properties of carvedilol can be translated to more superior clinical benefit compared to the other beta-blockers. Preliminary studies examining surrogate end points suggest that carvedilol may improve left ventricular ejection fraction (LVEF) more than metoprolol. More conclusive information regarding their relative effects of clinical outcomes will await the completion of the COMET study, which compares the effect of metoprolol and carvedilol on mortality and morbidity, expected at the end of the year 2002.