Increased circulating cytokines in patients with myocarditis and cardiomyopathy

Role of the cholinergic antiinflammatory pathway in murine autoimmune myocarditis

RATIONALE

This study was performed to gain insights into novel therapeutic approaches for the treatment of autoimmune myocarditis.

OBJECTIVE

Chemical stimulation of the efferent arm of the vagus nerve through activation of nicotinic acetylcholine receptor subtype-7α (α7-nAChR) has been shown to be protective in several models of inflammatory diseases. In the present study, we investigated the potentially protective effect of vagus nerve stimulation on myocarditis.

METHODS AND RESULTS

A/J mice were immunized with cardiac troponin I (TnI) to induce autoimmune myocarditis. Mice were exposed to drinking water that contained nicotine in different concentrations and for different time periods (for 3 days at 12.5 mg/L; 3 days at 125 mg/L; 21 days at 12.5 mg/L; and 21 days at 125 mg/L after first immunization). TnI-immunized mice with no pharmacological treatment showed extensive myocardial inflammation and fibrosis and significantly elevated levels of interleukin-6 and tumor necrosis factor-α. Furthermore, elevated levels of mRNA transcripts of proinflammatory chemokines (monocyte chemoattractant protein-1, macrophage inflammatory protein-1β, and RANTES) and chemokine receptors (CCR1, CCR2, and CCR5) were found. Oral nicotine administration reduced inflammation within the myocardium, decreased the production of interleukin-6 and tumor necrosis factor-α, and downregulated the expression of monocyte chemoattractant protein-1, macrophage inflammatory protein-1β, RANTES, CCR1, CCR2, and CCR5. In addition, nicotine treatment resulted in decreased expression of matrix metalloproteinase-14, natriuretic peptide precursor B, tissue inhibitor of metalloproteinase-1, and osteopontin, proteins that are commonly involved in heart failure. Finally, we found that nicotine reduced levels of pSTAT3 (phosphorylated signal transducer and activator of transcription 3) protein expression within the myocardium. Neostigmine treatment did not affect the progression of myocarditis.

CONCLUSIONS

We showed that activation of the cholinergic antiinflammatory pathway with nicotine reduces inflammation in autoimmune myocarditis. Our results may open new possibilities in the therapeutic management of autoimmune myocarditis.

Modulation of novel cardiorenal and inflammatory biomarkers by intravenous nitroglycerin and nesiritide in acute decompensated heart failure: an exploratory study

BACKGROUND

Modulation of novel cardiorenal and inflammatory markers may provide insight into the disease process and outcomes of patients with acute decompensated heart failure.

METHODS AND RESULTS

In this open-labeled, prospective, randomized study, 89 patients received either nesiritide (NES) or nitroglycerin (NTG) infusion by standard protocol. The serum or plasma concentrations of cystatin-C and inflammatory markers (high-sensitivity C-reactive protein, tumor necrosis factor-α, transforming growth factor-β1, and interleukin-6) were measured in 66 patients with acute decompensated heart failure at baseline and during drug infusion. Mean baseline values for demographics were not significantly different between NTG and NES groups; however, baseline inflammatory markers were elevated on admission. In NES compared with NTG groups, lower cystatin-C (1449 versus 2739 ng/mL, P<0.05) and IL-6 (25 versus 50 pg/mL, P<0.05) were observed. There were no significant differences in concentrations of high-sensitivity C-reactive protein, tumor necrosis factor-α, and transforming growth factor-β1 between groups over time.

CONCLUSIONS

The differential modulation effects of cystatin-C and interleukin-6 but not other inflammatory markers, in response to NES compared with NTG therapy, may provide important implications for vasodilator therapy. Further studies are warranted to confirm these findings.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00842023.

Olmesartan, an AT1 antagonist, attenuates oxidative stress, endoplasmic reticulum stress and cardiac inflammatory mediators in rats with heart failure induced by experimental autoimmune myocarditis

Studies have demonstrated that angiotensin II has been involved in immune and inflammatory responses which might contribute to the pathogenesis of immune-mediated diseases. Recent evidence suggests that oxidative stress may play a role in myocarditis. Here, we investigated whether olmesartan, an AT(1)R antagonist protects against experimental autoimmune myocarditis (EAM) by suppression of oxidative stress, endoplasmic reticulum (ER) stress and inflammatory cytokines. EAM was induced in Lewis rats by immunization with porcine cardiac myosin, were divided into two groups and treated with either olmesartan (10 mg/kg/day) or vehicle for a period of 21 days. Myocardial functional parameters measured by hemodynamic and echocardiographic analyses were significantly improved by the treatment with olmesartan compared with those of vehicle-treated rats. Treatment with olmesartan attenuated the myocardial mRNA expressions of proinflammatory cytokines, [Interleukin (IL)-1β, monocyte chemoattractant protein-1, tumor necrosis factor-α and interferon-γ)] and the protein expression of tumor necrosis factor-α compared with that of vehicle-treated rats. Myocardial protein expressions of AT(1)R, NADPH oxidase subunits (p47phox, p67phox, gp91phox) and the expression of markers of oxidative stress (3-nitrotyrosine and 4-hydroxy-2-nonenal), and the cardiac apoptosis were also significantly decreased by the treatment with olmesartan compared with those of vehicle-treated rats. Furthermore, olmesartan treatment down-regulated the myocardial expressions of glucose regulated protein-78, growth arrest and DNA damage-inducible gene, caspase-12, phospho-p38 mitogen-activated protein kinase (MAPK) and phospho-JNK. These findings suggest that olmesartan protects against EAM in rats, at least in part via suppression of oxidative stress, ER stress and inflammatory cytokines.

Telmisartan ameliorates experimental autoimmune myocarditis associated with inhibition of inflammation and oxidative stress

Excess cytokine produced by inflammatory stimuli contributes to the progression of myocardial damage in myocarditis. Angiotensin-II has been shown to play a pivotal role in the pathophysiology of various organs, especially the cardiovascular system. Some angiotensin II type 1 receptor antagonists are reported to inhibit proinflammatory cytokine production in vitro and in vivo. We investigated whether telmisartan, an angiotensin II type 1 receptor antagonist protects against experimental autoimmune myocarditis by suppression of inflammatory cytokines and oxidative stress. Experimental autoimmune myocarditis was induced in Lewis rats by immunization with porcine cardiac myosin. The rats were divided into two groups and treated with either telmisartan (10mg/kg/day) or vehicle for 21days. Age-matched normal rats without immunization were also included in this study. Myocardial functional parameters were significantly improved by treatment with telmisartan compared with vehicle-treated rats. Increased myocardial mRNA expressions of inflammatory cytokines [interleukin (IL-6), IL-1β, tumor necrosis factor-α and interferon-γ] were also suppressed by telmisartan treatment compared with vehicle-treated rats. Myocardial protein expressions of NADPH oxidase subunits p47phox, Nox-4, and gp91phox, myocardial levels of 8-hydroxydeoxyguanosine and 4-hydroxy-2-nonenal, and myocardial apoptosis were also significantly decreased by telmisartan treatment compared with vehicle-treated rats. Further, telmisartan significantly decreased endoplasmic reticulum stress markers in experimental autoimmune myocarditis rats. These findings suggest that telmisartan protects against experimental autoimmune myocarditis in rats, at least in part by suppressing inflammatory cytokines and oxidative stress; however, further investigations are needed before clinical use.

Beneficial effects of olmesartan, an angiotensin II receptor type 1 antagonist, in rats with dilated cardiomyopathy

Favorable effects of angiotensin II type 1 receptor blockers on patients with ischemic or idiopathic dilated cardiomyopathy (DCM) have already been suggested by several human trials, but their effects on DCM remain unknown. Hence, we investigated the effect of olmesartan on myocardial remodeling in a rat model in which myosin-induced experimental autoimmune myocarditis (EAM) might develop into DCM. EAM was elicited in Lewis rats by immunization with cardiac myosin, and 28 d after immunization, the surviving Lewis rats were divided into two groups and treated with either olmesartan (10 mg/kg/d) or vehicle. Age-matched normal rats without immunizations were also used. After four weeks of treatment, we investigated the effects of olmesartan on cardiac function, inflammatory cytokines and cardiac remodeling in EAM rats. Myocardial functional parameters measured by hemodynamic and echocardiographic analyses were significantly improved by the treatment with olmesartan compared with those of vehicle-treated rats. Olmesartan significantly reduced cardiac fibrosis as well as hypertrophy and its molecular markers (left ventricular [LV] mRNA expressions of transforming growth factor beta1, collagen-I and -III, and atrial natriuretic peptide) compared with those of vehicle-treated rats. Increased myocardial mRNA expressions of proinflammatory cytokines (interleukin [IL]-6, IL-1β), monocyte chemoattractant protein-1 and matrix metalloproteinases (MMP-2 and -9) were also suppressed by the treatment with olmesartan in rats with DCM. Further, the plasma level of angiotensin II was significantly increased in olmesartan-treated rats. These findings demonstrate that olmesartan treatment significantly improved LV function and ameliorated the progression of cardiac remodeling in rats with DCM after EAM.

Cetirizine a histamine H1 receptor antagonist improves viral myocarditis

BACKGROUND

We showed that mast cells played a critical role in the progression of heart failure induced by pressure overload and viral myocarditis in mice. In this study, we investigated the effect of cetirizine, a selective H1 receptor antagonist, on experimental viral myocarditis induced by encephalomyocarditis (EMC) virus.

METHODS

Four-week-old inbred male DBA/2 mice were inoculated intraperitoneally with 10 plaque-forming units (pfu) of the EMC virus. Cetirizine was administered orally at a dose of 1 or 10 mg/kg per day for the survival study, and 1 mg/kg for the histologic and gene expression studies, beginning on the day of viral inoculation.

RESULTS

Cetirizine improved survival dose dependently. Heart weight to body weight ratio was significantly decreased in mice treated with cetirizine. The area of myocardial necrosis was significantly smaller in the hearts of mice treated with cetirizine compared with controls. Gene expressions of tumor necrosis factor, interleukin 6, and metalloproteinase 2 were significantly suppressed in the hearts of mice treated with cetirizine.

CONCLUSION

These results suggest that cetirizine exerts its beneficial effects on viral myocarditis by suppressing expression of pro-inflammatory cytokines, genes related to cardiac remodeling in the hearts of mice.

Telmisartan, an angiotensin-II receptor blocker ameliorates cardiac remodeling in rats with dilated cardiomyopathy

Multiple trials over the past several years have examined indications for angiotensin receptor blockers (ARBs) in the treatment of left ventricular (LV) dysfunction, both acutely after myocardial infarction and in chronic heart failure (CHF). However, the effects of telmisartan, an ARB in rats with CHF after experimental autoimmune myocarditis (EAM) have not yet been analyzed. CHF was elicited in Lewis rats by immunization with cardiac myosin, and 28 days after immunization, the surviving Lewis rats were divided into two groups and treated with either telmisartan (10 mg kg(-1) day(-1)) or vehicle. After 4 weeks of treatment, we analyzed the effects of telmisartan on cardiac function, proinflammatory cytokines and cardiac remodeling in EAM rats. Myocardial functional parameters measured by hemodynamic and echocardiographic studies were significantly improved by telmisartan treatment in rats with CHF compared with those of vehicle-treated rats with CHF. Telmisartan significantly reduced levels of cardiac fibrosis, hypertrophy and its marker molecules (LV mRNA expressions of transforming growth factor beta 1, collagen I and III, and atrial natriuretic peptide), and peroxisome proliferator-activated receptor--gamma protein expression compared with those of vehicle-treated rats. CHF-induced increases in myocardial mRNA expressions of proinflammatory cytokines, (interleukin (IL)-6, IL-1beta), monocyte chemoattractant protein-1 and matrix metalloproteinases (MMP-2 and -9) were also suppressed by the treatment with telmisartan. Moreover, the plasma level of angiotensin-II was significantly elevated in telmisartan-treated rats. Our results indicate that telmisartan treatment significantly improved LV function and ameliorated the progression of cardiac remodeling in rats with CHF after EAM.

Echocardiographic manifestations of pandemic 2009 (H1N1) influenza a virus infection

SUMMARY AIM: The prevalence of myocardial involvement in influenza infection ranges from 0% to 12% depending on the diagnostic criteria used to define myocarditis. Whether such an association holds for the novel influenza A strain, pandemic-2009-H1N1, remains unknown. The aim of this present study is to evaluate the cardiovascular manifestations of pandemic (H1N1) 2009 influenza A (pH1N1) by using standard echocardiography and tissue Doppler imaging (TDI).

METHODS

Twenty-eight young patients who had been hospitalized for at least 24 h due to an influenza-like illness and tested positive for pH1N1 by real-time polymerase chain reaction were included in the study. All patients underwent echocardiographic studies during the first 72 h of admission. Echocardiographic studies of thirty gender and age matched control subjects were performed and the results were compared.

RESULTS

Heart rate was significantly higher in patients infected with pH1N1 virus. Other clinical variables were similar between the two groups (p > 0.05). Echocardiographic variables were also similar except left ventricular end-systolic dimension, which was significantly increased in the patient group (P = 0.042). Left ventricular tissue Doppler assessment at mitral annulus showed that mean systolic velocities of pH1N1 infected patients and control group were statistically similar. However, early diastolic velocity was decreased and late diastolic velocity was increased in the patient group. Therefore early diastolic/late diastolic velocity ratio was significantly decreased in pH1N1 infected patients. Also, isovolumetric contraction time and isovolumetric relaxation time were prolonged and ejection time was significantly shortened in pH1N1 infected patients. As a result, global myocardial performance index was significantly higher in pH1N1 infected patients (p < 0.001). Right ventricular tissue Doppler assessment at tricuspid annulus showed similar results with the left ventricular measurements.

CONCLUSION

The results of the study suggest an association between hospitalized pH1N1 and subclinical cardiac dysfunction as measured by tissue Doppler echocardiography.

Homocysteine and pro-inflammatory cytokine concentrations in acute heart disease

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

gp130-mediated pathway and heart failure

Binding of ligands to gp130 activates at least three different downstream signaling pathways: the signal transducer and activator of transcription (STAT), the Src-homology tyrosine phosphatase 2-ras-MAPK and the PI3K/Akt pathways. Cardiac-specific disruption of gp130 was shown to result in heart failure in response to mechano-stress accompanied by an increase in apoptosis of cardiac myocytes. Inactivation of STAT3 resulting from the loss of gp130 may be a key event in the transition from cardiac hypertrophy to heart failure. Proper vascular growth would be essential for normal cardiac development and the remodeling process. In addition to various factors, such as bcl-xL, inducible nitric oxide synthase and reactive oxygen species-scavenging proteins, VEGF has also been identified as a target gene of STAT3 and together can promote cardiac myocyte survival by preventing apoptosis and restoration of energy deprivation. In this regard, the gp130-receptor system and its main downstream mediator, STAT3, play a key role in the prevention of heart failure. In this review, current knowledge of the IL-6 family of cytokines relating to human cardiac disease is summarized, in addition to the potential role of gp130-mediated signaling systems in various models of experimental heart failure.

Diagnosis and treatment of viral myocarditis

Myocarditis, an inflammatory disease of heart muscle, is an important cause of dilated cardiomyopathy worldwide. Viral infection is also an important cause of myocarditis, and the spectrum of viruses known to cause myocarditis has changed in the past 2 decades. Several new diagnostic methods, such as cardiac magnetic resonance imaging, are useful for diagnosing myocarditis. Endomyocardial biopsy may be used for patients with acute dilated cardiomyopathy associated with hemodynamic compromise, those with life-threatening arrhythmia, and those whose condition does not respond to conventional supportive therapy. Important prognostic variables include the degree of left and right ventricular dysfunction, heart block, and specific histopathological forms of myocarditis. We review diagnostic and therapeutic strategies for the treatment of viral myocarditis. English-language publications in PubMed and references from relevant articles published between January 1, 1985, and August 5, 2008, were analyzed. Main keywords searched were myocarditis, dilated cardiomyopathy, endomyocardial biopsy, cardiac magnetic resonance imaging, and immunotherapy.

Inflammatory markers and cardiac function in acute coronary syndrome: difference in ST-segment elevation myocardial infarction (STEMI) and in non-STEMI models

PURPOSE

No studies have been addressed to the differences in inflammation kinetics between ST-segment elevation myocardial infarction (STEMI) and non-ST-segment elevation myocardial infarction (NSTEMI).

PATIENTS AND METHODS

Forty consecutive patients with acute coronary syndrome (ACS) (n=23 STEMI, age=61.7+/-10.3 years; n=17 NSTEMI, age=65.6+/-11.3 years) were enrolled within 12h after symptoms. All patients received therapy according to the current Guidelines. Blood samples were collected at admission (t0), on days 7 (t1) and 30 (t2) to evaluate CD40 ligand (CD40L), transforming growth factor (TGF)-beta, interleukin (IL)-6, tumor necrosis factor (TNF)-alpha and its receptors TNFRI and TNFRII, high sensitivity C-reactive protein (hs-CRP), serum amyloid A (SAA) and white blood cells (WBC). Echocardiographic parameters were also evaluated.

RESULTS

STEMI patients, at admission, had significantly higher median values of hs-CRP (p<0.001), WBC (p<0.01), ferritin (p<0.0005) and IL-6 (p<0.05) than NSTEMI. On the contrary, NSTEMI patients had lower median levels of every inflammatory marker except for CD40L (p<0.05) that was significantly higher. Moreover, three out of four deceased patients presented levels of CD40L higher than the median. At admission, STEMI showed a reduced ejection fraction (EF, p<0.01) and increased wall motion score index (WMSI, p<0.001) and end-diastolic volume (EDV, p<0.05) vs NSTEMI. An inverse correlation between admission values of inflammatory markers (SAA and WBC) and cardiac function was observed (p<0.05). Moreover, the necrosis marker troponin I was positively correlated with both WMSI (p<0.05) and hs-CRP (p<0.05). Regarding the inflammation kinetics, a difference was observed in the two groups only for WBC (p<0.05) and SAA (p<0.05). SAA showed higher values in STEMI at t0 and t1. In both groups, TGF-beta had an increase at t1 and t2 with respect to admission, while IL-6 had a decreasing trend. The total incidence of major adverse clinical events (MACE) was 22.5% at t2, with a mortality rate of 10%.

CONCLUSION

These observations suggest a differential inflammatory pattern in STEMI and NSTEMI patients. The absence of significant correlations between inflammatory indexes and myocardial infarction in NSTEMI supports the hypothesis that a different pattern of inflammation occurs in these patients. CD40L may have an important role as a marker for risk stratification in patients with ACS.

Spontaneous autoimmune myocarditis and cardiomyopathy in HLA-DQ8.NODAbo transgenic mice

Most individuals have viral infections at some point in their life, however, only few develop autoreactivity to cardiac myosin following infection suggesting a genetic predisposition. Population studies have shown that among all the genetic factors linked with autoimmune disease development, MHC class II genes are the most significant genetic factors. Experimental autoimmune myocarditis resembling human Dilated cardiomyopathy can be induced in susceptible mice by infection with coxsackie virus as well as immunization with purified foreign and murine cardiac specific a-myosin. We generated transgenic mice lacking endogenous class II molecules, HLA-DR3.Abo and HLA-DQ8.Abo transgenic mice in NOD and HLA-DQ8.Abo in B10 background, to study the role of MHC in spontaneous autoimmunity. The HLA molecules in these mice are expressed on cell surface and can positively select CD4+ T cells expressing various Vb T cell receptors. NOD.DQ8 female mice spontaneously developed myocarditis and dilated cardiomyopathy. Histopathology of heart revealed mononuclear infiltrate consisting of CD4 and Mac-1+ cells and myocyte necrosis. NOD.DQ8 mice showed cellular and humoral autoreactive response to self cardiac myosin.. Depletion of CD8 and CD4 + cells suggested that CD8 T cells may act as regulatory cells while CD4 cells are required as effector cells. NOD.DR3 and B10.DQ8 mice did not develop any cardiac pathology suggesting DQ8 is required for predisposition to the spontaneous autoreactivity while NOD background influences onset and progression of disease. Thus these mice provide powerful tools to understand the role of HLA class II molecules in predisposition and onset of human diseases and to develop immunotherapy.

Cytokines and matrix metalloproteinases as potential biomarkers in chronic heart failure

Heart failure (HF) is accompanied by the upregulation of bioactive signaling molecules, known as cytokines, and a family of downstream proteases, matrix metalloproteinases (MMPs). It is now apparent that these molecules contribute to adverse myocardial remodeling during HF. Elevated levels of cytokines and MMPs exist in the myocardium and can subsequently spill over into the systemic circulation. The purpose of this article is to examine clinical studies of HF that have quantified levels of different types of cytokines, MMPs and endogenous tissue inhibitors of MMPs in relation to this disease process. HF is a complex syndrome that can develop from various etiologies and can be characterized into two distinct phenotypes: systolic and diastolic. This article will present recent clinical studies that have identified significant differences between the cytokine and MMP circulating profile of systolic and diastolic HF patients. In general, elevated levels of cytokines and MMPs exist in systolic HF patients when compared with diastolic HF patients, whereas diastolic HF patients have elevated levels of cytokines and MMPs when compared with controls. Therefore, future studies distinguishing between HF phenotypes may provide more consistent results in determining possible analytes to be used as biomarkers. Furthermore, this article will emphasize why standardization of analytical techniques and establishment of referent cytokine and MMP levels are necessary if these analytes are to be used as biomarkers for the diagnosis, prognosis and evaluation of treatment in the context of HF.

Viral causes of human myocarditis

The diagnosis of acute myocarditis is complex and challenging. The use of the Dallas criteria in the diagnosis of myocarditis is associated with poor sensitivity and specificity because of the sampling error related to the often focal distribution of the specific histological lesions in cardiac tissue and the variability in pathological interpretation. To improve histological diagnosis, additional virological evaluation of cardiac tissues is required, with immunohistochemical and polymerase chain reaction (PCR) techniques allowing identification and quantification of viral infection markers. The diagnostic gold standard is endomyocardial biopsy (EMB) with the histological Dallas criteria, in association with new immunohistochemical and PCR analyses of cardiac tissues. Using real-time PCR and reverse transcription PCR assays, parvovirus B19, Coxsackie B virus, human herpesvirus 6 (HHV-6) type B and adenovirus have been detected in 37, 33, 11 and 8% of EMB, respectively, from young adults (aged<35 years) with histologically proven acute myocarditis. Viral co-infections have also been found in 12% of acute myocarditis cases, generally parvovirus B19 plus HHV-6. Moreover, herpesviruses such as the Epstein-Barr virus or cytomegalovirus can also be associated with myocarditis after heart transplantation. During the clinical course of myocarditis, the immunohistochemical detection of enterovirus, adenovirus or parvovirus B19 capsid proteins or herpesvirus late proteins is necessary to differentiate a viral cardiac infection with replication activities from a persistent or latent cardiac infection. These new viral diagnostic approaches can lead to better identification of the aetiology of myocarditis and may therefore enable the development and evaluation of specific aetiology-directed treatment strategies.

Global gene expression profiling in the failing myocardium

Heart failure (HF) is a syndrome that involves multiple cellular mechanisms leading to a common phenotype of reduced ventricular contraction and cardiac chamber dilation. To clarify the mechanisms, a number of microarray analyses of the failing myocardium have been conducted. Gene expression profiles are usually compared between opposing pairs of samples, such as non-failing vs failing hearts, ischemic vs non-ischemic hearts, male vs female failing hearts or atria vs ventricles of failing hearts. Apart from these conventional methods, a different novel approach identified cardiac myosin light chain kinase (MLCK) as a HF-related gene by the comprehensive search for the genes that had an expression level that strongly correlated with the severity of HF; further investigations proved the important role of cardiac MLCK in HF. Moreover, a robust gene expression signature composed of 27 genes was revealed on analysis of 4 independent microarray data sets from the failing myocardium of dilated cardiomyopathy. The authors newly demonstrate 107 HF-related genes that were listed in 2 or more of 7 microarray data sets previously reported. Among these genes, many were observed to be involved in mitochondrial dysfunction and oxidative phosphorylation and 3 extracellular molecules, including periostin, pleiotrophin, and SERPINA3, which might become novel diagnostic and therapeutic targets for HF. These novel strategies warrant the new identification of specific genes that are linked to the pathophysiology of HF.

Beneficial Effect on Cardiac Function by Intravenous Immunoglobulin Treatment in Patients with Dilated Cardiomyopathy is not due to Neutralization of Anti-receptor Autoantibody

Anti-beta1-adrenoceptor (beta1AR) autoantibodies have been shown to be pathophysiologically important in idiopathic dilated cardiomyopathy (DCM). Treatment with intravenous immunoglobulin (IVIG) has shown beneficial effects in both DCM and ischemic cardiomyopathy. However, the underlying mechanism has not been clarified. In the present study, we therefore examined whether the improvement of cardiac function was due to neutralization of functional beta1AR autoantibodies by anti-idiotypic antibodies. Autoantibodies against the beta1AR was analysed in sera from patients with DCM and coronary artery disease (CAD) treated with IVIG or placebo before, 6 and 12 months. Six month after treatment, DCM patients showed increase in beta1AR autoantibodies, mostly in IgG1 and IgG2, whereas in CAD patients mostly in IgG2. No changes in beta1AR autoantibodies after 12 months were detected. In summary, our results indicate that improvement of cardiac function by IVIG is not due to neutralization of beta1AR autoantibodies.

The eNOS enhancer AVE 9488: a novel cardioprotectant against ischemia reperfusion injury

Nitric oxide (NO) is an important regulator of vascular and myocardial function. Cardiac ischemia/reperfusion injury is reduced in mice overexpressing endothelial NO synthase (eNOS) suggesting cardioprotection by eNOS. Novel pharmacological substances, so called eNOS enhancers, upregulate eNOS expression and thereby increase NO production. We tested the effects of the eNOS enhancer AVE 9488 on cardiac ischemia/reperfusion injury in vivo in mice. After treatment with the eNOS enhancer AVE 9488 (30 mg/kg/day) or placebo for one week mice underwent 30 min of coronary artery ligation and 24 h of reperfusion in vivo. Ischemia-reperfusion damage was significantly reduced in mice treated with the eNOS enhancer when compared to placebo treated mice (infarct/area at risk 65.4 +/- 4.1 vs. 36.9 +/- 4.0%, placebo vs. eNOS enhancer, P = 0.0002). The protective effect was blunted in eNOS knockout mice treated with the eNOS enhancer (infarct/area at risk 64.1 +/- 6.2%, eNOS knockout + eNOS enhancer vs. WT + eNOS enhancer, P = ns). Reactive oxygen species were significantly reduced in mice treated with the eNOS enhancer as indicated by significantly lower malondialdehyde-thiobarbituric acid levels (placebo vs. eNOS enhancer, 3.2 +/- 0.5 vs. 0.8 +/- 0.07 micromol/l, P = 0.0003). Thus pharmacological interventions addressed to increase eNOS-derived NO production constitute a promising therapeutic approach to prevent myocardial ischemia/reperfusion injury.

Relationship between circulating levels of monocyte chemoattractant protein-1 and systolic dysfunction in patients with hypertrophic cardiomyopathy

BACKGROUND

Progression of hypertrophic cardiomyopathy (HCM) to left ventricular dilatation and systolic dysfunction sometimes occurs. However, the mechanism of the transition from hypertrophy to dysfunction has not been elucidated. It has been reported that circulating levels of monocyte chemoattractant protein-1 (MCP-1), which is a major factor promoting the accumulation of macrophages, are increased in patients with congestive heart failure. We measured circulating levels of MCP-1 in patients with HCM and examined whether MCP-1 was expressed in the myocardium of HCM patients. We also examined whether circulating levels of MCP-1 were correlated with left ventricular dysfunction.

METHODS

Circulating levels of MCP-1 were measured by an enzyme immunoassay in 26 patients with HCM (60+/-2 years old) and 20 control subjects (57+/-2 years old). Cardiac function was evaluated by two-dimensional echocardiography and cardiac catheterization.

RESULTS

HCM patients had significantly elevated levels of MCP-1 (HCM: 309+/-30 vs. control: 178+/-8 pg/ml, P<.001). MCP-1 levels in patients with systolic dysfunction were significantly higher than those in patients without systolic dysfunction (P<.05) and were also significantly higher than those in patients with outflow obstruction (P<.05). Immunohistochemical analysis revealed that MCP-1 was expressed in endomyocardial biopsy samples obtained from HCM patients with systolic dysfunction. Furthermore, MCP-1 levels were inversely correlated with fractional shortening (r=-.401, P<.05) and correlated with left ventricular end-diastolic pressure (r=-.579, P<.01).

CONCLUSION

These results show that MCP-1 is associated with, and might be involved in the pathogenesis of, left ventricular systolic dysfunction in patients with HCM.

Serial circulating concentrations of C-reactive protein, interleukin (IL)-4, and IL-6 in patients with acute left heart decompensation

BACKGROUND

Interleukin (IL)-6 has recently been shown to have negative inotropic effects, and several studies have reported increases in circulating concentrations of this cytokine in patients with depressed left ventricular ejection fraction and chronic left heart failure. However, most previous clinical studies have measured cytokines in compensated chronic heart failure.

HYPOTHESIS

The purpose of this study was to examine the temporal evolution of circulating concentrations of C-reactive protein (CRP) and cytokines in patients with cardiomyopathy and acute cardiac decompensation, free of infection and unstable angina.

METHODS

The time course of circulating concentrations of CRP, an anti-inflammatory cytokine interleukin (IL)-4, and a proinflammatory cytokine IL-6 were studied in eight patients with cardiomyopathy and acute cardiac decompensation in the absence of infection or unstable angina. Control samples were obtained from eight age-matched asymptomatic subjects.

RESULTS

Increased circulating concentrations of CRP (2.6 +/- 0.8 mg/dl), IL-4 (164.6 + 36.5 pg/ml), and IL-6 (17.1 +/- 5.1 pg/ml) were found in all eight patients during acute cardiac decompensation; these values decreased significantly with the resolution of symptoms of cardiac decompensation (0.5 +/- 0.1 mg/dl, 77.8 +/- 23.6 pg/ml, 2.3 +/- 0.1 pg/ml, respectively, p < 0.05 for both). There was a significant correlation between peak CRP and peak IL-6 (p < 0.05).

CONCLUSIONS

In patients with acute left heart decompensation in the absence of infection or coronary events, CRP, IL-4, and IL-6 increased and returned toward normal levels as the symptoms of heart failure resolved. Since the changes in concentrations of CRP, IL-4, and IL-6 in patients with heart failure are dynamic, the distinction between compensated and decompensated state is important when discussing the significance of acute reactive proteins or cytokines in the pathogenesis of heart failure.

Can cocaine abuse exacerbate the cardiac toxicity of human immunodeficiency virus?

Both cocaine use and human immunodeficiency virus (HIV) infection alone have been associated with an increased incidence of cardiac dysfunction. Concomitant exposure to cocaine and HIV infection may exacerbate the cardiac toxicity of either agent alone, a hypothesis that is examined in this review article. A possible unifying hypothesis based on enhancement of adrenergic stimulation is proposed.

Role of the innate immune system in acute viral myocarditis

Although the adaptive immune system is thought to play an important role in the pathogenesis of viral myocarditis, the role of the innate immune system has not been well defined. To address this deficiency, we employed a unique line of mice that harbor a genomic "knock in" of a mutated TNF gene lacking the AU rich element (TNF(ARE/ARE)) that is critical for TNF mRNA stability and translation, in order to examine the contribution of the innate immune system in encephalomyocarditis-induced myocarditis (EMCV). Heterozygous mice (TNF(ARE/+)) were infected with 500 plaque-forming units of EMCV. TNF(ARE/+)mice had a significantly higher 14-day mortality and myocardial inflammation when compared to littermate control mice. Virologic studies showed that the viral load at 14 days was significantly lower in the hearts of TNF(ARE/+) mice. TNF(ARE/+) mice had an exaggerated proinflammatory cytokine and chemokine response in the heart following EMCV infection. Modulation of the innate immune response in TNF(ARE/+) mice by the late administration of prednisolone resulted in a significant improvement in survival and decreased cardiac inflammation, whereas early administration of prednisolone resulted in a blunted innate response and increased mortality in littermate control mice. Viewed together, these data suggest that the duration and degree of activation of the innate immune system plays a critical role in determining host outcomes in experimental viral myocarditis.

Proinflammatory cytokine and ligands modulate cardiac peroxisome proliferator-activated receptors

BACKGROUND

Peroxisome proliferator-activated receptors (PPAR) mediate inflammatory processes and alter cardiac function. However, it is not clear whether inflammatory cytokines or PPAR ligands regulate PPARs in the cardiomyocytes to modulate cardiac functions. We investigated the effects of tumour necrosis factor-alpha (TNF-alpha) and PPAR ligands on the expression of PPARs in HL-1 cardiomyocytes.

MATERIALS AND METHODS

HL-1 cardiomyocytes were incubated with and without TNF-alpha (1, 10, 25 and 50 ng mL(-1)) or PPAR ligands (rosiglitazone, pioglitazone and fenofibrate) at concentrations of 0.1, 1 and 10 microM for 24 h. The cells also received SN-50 (NF-kappaB inhibitor, 50 microg mL(-1)), ascorbic acid (100 microM) and coenzyme Q10 (10 microM) alone or combined with TNF-alpha.

RESULTS

Using reverse transcriptase-polymerase chain reaction and Western blot, we found that incubation of TNF-alpha (50 ng mL(-1)) for 24 h decreased PPAR-alpha, but increased PPAR-gamma without altering PPAR-delta. These effects were not changed by co-administration of SN-50. However, co-administration of ascorbic acid prevented the effect of TNF-alpha both on PPAR-alpha and PPAR-gamma. Coenzyme Q10 partially attenuated the effect of TNF-alpha on PPAR-gamma but did not alter its effect on PPAR-alpha. The administration of rosiglitazone (10 microM) and pioglitazone (10 microM) for 24 h increased PPAR-gamma mRNA, but did not alter PPAR-alpha or PPAR-delta. Moreover, fenofibrate (0.1, 1 and 10 microM) increased PPAR-gamma without any effects on PPAR-alpha or PPAR-delta.

CONCLUSIONS

Oxidative stress causes the regulations of PPAR-alpha and PPAR-gamma in the TNF-alpha-treated cardiomyocytes. The up-regulation of PPAR-gamma by PPAR ligands may contribute to their anti-inflammation effects.

Cardiac cachexia: a systematic overview

Cardiac cachexia as a terminal stage of chronic heart failure carries a poor prognosis. The definition of this clinical syndrome has been a matter of debate in recent years. This review describes the ongoing discussion about this issue and the complex pathophysiology of cardiac cachexia and chronic heart failure with particular focus on immunological, metabolic, and hormonal aspects at the intracellular and extracellular level. These include regulators such as neuropeptide Y, leptin, melanocortins, ghrelin, growth hormone, and insulin. The regulation of feeding is discussed as are nutritional aspects in the treatment of the disease. The mechanisms of wasting in different body compartments are described. Moreover, we discuss several therapeutic approaches. These include appetite stimulants like megestrol acetate, medroxyprogesterone acetate, and cannabinoids. Other drug classes of interest comprise angiotensin-converting enzyme inhibitors, beta-blockers, anabolic steroids, beta-adrenergic agonists, anti-inflammatory substances, statins, thalidomide, proteasome inhibitors, and pentoxifylline.

Acute effect of antidiabetic 1,4-dihydropyridine compound cerebrocrast on cardiac function and glucose metabolism in the isolated, perfused normal rat heart

Diabetes mellitus (DM) is an important cardiovascular risk factor and is associated with abnormalities in endothelial and vascular smooth muscle cell function, evoked by chronic hyperglycemia and hyperlipidemia. Chronic insulin deficiency or resistance is marked by decreases in the intensity of glucose transport, glucose phosphorylation, and glucose oxidation, plus decreases in ATP levels in cardiac myocytes. It is important to search for new agents that promote glucose consumption in the heart and partially inhibit extensive fatty acid beta-oxidation observed in diabetic, ischemia. When the oxygen supply for myocardium is decreased, the heart accumulates potentially toxic intermediates of fatty acid beta-oxidation, that is, long-chain acylcarnitine and long-chain acyl-CoA metabolites. Exogenous glucose and heart glycogen become an important compensatory source of energy. Therefore we studied the effect of the antidiabetic 1,4-dihydropyridine compound cerebrocrast at concentrations from 10(-10) M to 10(-7) M on isolated rat hearts using the method of Langendorff, on physiological parameters and energy metabolism. Cerebrocrast at concentrations from 10(-10) M to 10(-7) M has a negative inotropic effect on the rat heart. It inhibits L-type Ca(2+)channels thereby diminishing the cellular Ca(2+) supply, reducing contractile activity, and oxygen consumption, that normally favors enhanced glucose uptake, metabolism, and production of high-energy phosphates (ATP content) in myocardium. Cerebrocrast decreases heart rate and left ventricular (LV) systolic pressure; at concentrations of 10(-10) M and 10(-9) M it evokes short-term vasodilatation of coronary arteries. Increase of ATP content in the myocytes induced by cerebrocrast has a ubiquitous role. It can preserve the integrity of the cell plasma membranes, maintain normal cellular function, and inhibit release of lactate dehydrogenase (LDH) from cells that is associated with diabetes and heart ischemia. Administration of cerebrocrast together with insulin shows that both compounds only slightly enhance glucose uptake in myocardium, but significantly normalize the rate of contraction and relaxation ( +/- dp/dt). The effect of insulin on coronary flow is more pronounced by administration of insulin together with cerebrocrast at a concentration of 10(-7) M. Cerebrocrast may promote a shift of glucose consumption from aerobic to anerobic conditions (through the negative inotropic properties), and may be very significant in prevention of cardiac ischemic episodes.

Right ventricular beneficial effects of beta adrenergic receptor kinase inhibitor (betaARKct) gene transfer in a rat model of severe pressure overload

Heart failure is associated with abnormalities in betaAR cascade regulation, calcium cycling, expression of inflammatory mediators and apoptosis. Adenoviral mediated gene transfer of betaARKct has beneficial indirect effects on these pathologic processes upon the left ventricular myocardium. The concomitant biochemical changes that occur in the right ventricle have not been well characterized. Sprague-Dawley rats underwent aortic banding and were followed by echocardiography. After a decrease in fractional shortening of 25% from baseline, intracoronary injection of adenoviral-betaARKct (n=14) or adenoviral-beta-galactosidase (control, n=13) was performed. Rats were randomly euthanized on post-operative day 7, 14 or 21. Protein analysis including RV myocardial levels of betaARKct, betaARK1, SERCA(2a), inflammatory tissue mediators (IL-1, IL-6 and TNF-alpha), apoptotic markers (bax and bak), and MAP kinases (jnk, p38 and erk) was performed. ANOVA was employed for group comparison. Adenoviral-betaARKct treated animals showed increased expression of betaARKct and decreased levels of betaARK1 compared with controls. This treatment group also demonstrated normalization of SERCA(2a) expression and decreased levels of the inflammatory markers IL-1, IL-6 and TNF-alpha. The pro-apoptotic markers bax and bak were similarly improved. Ventricular levels of the MAP kinase jnk were increased. Differences were most significant 7 days after gene transfer, but the majority of these changes persisted at 21 days. These results suggest that attenuation of the pathologic mechanisms of beta adrenergic receptor desensitization, SERCA(2a) expression, inflammation and apoptosis, not only occur in the left ventricle but also in the right ventricular myocardium after intracoronary gene transfer of betaARKct during heart failure.

Tumor necrosis factor-alpha and mortality in heart failure: a community study

BACKGROUND

Tumor necrosis factor-alpha (TNFalpha), an inflammatory cytokine, was reported to be elevated in trials of heart failure (HF) with reduced ejection fraction (EF) and associated with mortality. Whether this is true for HF with preserved EF is unknown, and community data are lacking. We evaluated the distribution of TNFalpha, its association with baseline characteristics and mortality, and its benefit in assessing risk in community HF patients.

METHODS AND RESULTS

Olmsted County residents with active HF from July 2004 to March 2007 (n=486; mean age, 76.7 years; EF > or =50%, 55%) were prospectively recruited. Clinical characteristics and TNFalpha were measured. Elevated TNFalpha (more than the assay limit of normal of 2.8 pg/mL) was present in 143 (29%). Higher TNFalpha was associated with decreased creatinine clearance, nonsmoking status, anemia, and greater comorbidity (P(trend)<0.05 for all). Mortality increased with increasing TNFalpha (P=0.016), with 1-year mortality estimates of 16%, 18%, 23%, and 32% from the lowest to highest quartile, respectively. After adjustment for age, sex, and EF, the hazard ratios for death were 1.24, 1.37, and 1.90 from the second to the highest TNFalpha quartile, respectively (P(trend)=0.007). TNFalpha contributed to risk assessment as indicated by increases in the area under the receiver operating characteristic curves in all models examined (P<0.05 for all). Results did not differ by EF (P=0.60 interaction term of TNFalpha and EF).

CONCLUSIONS

TNFalpha was elevated in a large portion of community HF patients, was associated with a large decrease in survival, and provided a significant incremental increase in risk assessment above established indicators. TNFalpha is useful for risk assessment in HF patients with preserved and reduced EF.

Cardiovascular manifestations associated with influenza virus infection

Influenza accounts for 3 to 5 million cases of severe illness and up to 300,000 deaths annually. Cardiovascular involvement in acute influenza infection can occur through direct effects of the virus on the myocardium or through exacerbation of existing cardiovascular disease. Epidemiological studies have demonstrated an association between influenza epidemics and cardiovascular mortality and a decrease in cardiovascular mortality in high risk patients has been demonstrated following vaccination with influenza vaccine. Influenza is a recognised cause of myocarditis which can lead to significant impairment of cardiac function and mortality. With recent concerns regarding another potential global pandemic of influenza the huge potential for cardiovascular morbidity and mortality is discussed.

Mast cells play a critical role in the pathogenesis of viral myocarditis

BACKGROUND

Mast cells are powerful producers of multiple cytokines and chemical mediators playing a pivotal role in the pathogenesis of various cardiovascular diseases. We examined the role of mast cells in murine models of heart failure due to viral myocarditis, using 2 strains of mast cell-deficient mice.

METHODS AND RESULTS

Two strains of mast cell-deficient mice, WBB6F1-Kit(W)/Kit(W-v) (W/W(V)) and WCB6F1-Kitl(Sl)/Kitl(Sl-d) (Sl/Sl(d)), were inoculated with 10 plaque-forming units of the encephalomyocarditis virus intraperitoneally. On day 14 after inoculation, survival of W/W(V) mice was significantly higher than that of their control littermates (77% versus 31%; P=0.03; n=13). On histological examination on day 7, myocardial necrosis and cellular infiltration were significantly less pronounced in W/W(V) and Sl/Sl(d) mice than in their control littermates (area of infiltration, 7.6+/-3.5% versus 29.3+/-15.6%; P=0.002; area of necrosis, 7.6+/-3.5% versus 30.0+/-17.2%; P=0.003; n=10). Histological examination showed more severe changes in mast cell-reconstituted than in -nonreconstituted W/W(V) and Sl/Sl(d) mice. The gene expressions of mast cell proteases were upregulated in the acute phase of viral myocarditis and rose further in the subacute phase of heart failure. Their activation coincided with the development of myocardial necrosis and fibrosis and correlated with the upregulation of gene expression of matrix metalloproteinase-9. The histamine H1-receptor antagonist bepotastine improved encephalomyocarditis viral myocarditis.

CONCLUSIONS

These observations suggest that mast cells participate in the acute inflammatory reaction and the onset of ventricular remodeling associated with acute viral myocarditis and that the inhibition of their function may be therapeutic in this disease.

Molecular biology and pathogenesis of viral myocarditis

Myocarditis is a cardiac disease associated with inflammation and injury of the myocardium. Several viruses have been associated with myocarditis in humans. However, coxsackievirus B3 is still considered the dominant etiological agent. The observed pathology in viral myocarditis is a result of cooperation or teamwork between viral processes and host immune responses at various stages of disease. Both innate and adaptive immune responses are crucial determinants of the severity of myocardial damage, and contribute to the development of chronic myocarditis and dilated cardiomyopathy following acute viral myocarditis. Advances in genomics and proteomics, and in the use of informatics and biostatistics, are allowing unbiased initial evaluations that can be the basis for testable hypotheses about virus pathogenesis and new therapies.

HLA-DPbeta chain may confer the susceptibility to hepatitis C virus-associated hypertrophic cardiomyopathy

Hypertrophic cardiomyopathy (HCM) is a heart muscle disease characterized by hypertrophy and diastolic dysfunction of cardiac ventricles. It is suggested that one possible aetiology of HCM is the hepatitis C virus (HCV) infection, but molecular mechanisms underlying development of HCV-associated HCM (HCV-HCM) remains unknown. Because the human leucocyte antigen (HLA) molecule is involved in the control of progression/suppression of viral infection, extensive HLA allelic diversity may modulate the post-infectious course of HCV and pathogenesis of HCV-HCM. Here we undertook a case-control study with 38 patients with HCV-HCM and 132 unrelated healthy controls to reveal the potential impact of polymorphisms in seven classical and two non-classical HLA genes on the pathogenesis of HCV-HCM. It was found that DPB1*0401 and DPB1*0901 were significantly associated with increased risk to HCV-HCM in dominant model (P < 0.028, OR = 3.94, 95% confidence interval (CI) = 1.19, 13.02) and in recessive model (P < 0.007, OR = 9.85, 95% CI = 1.83, 53.04), respectively. The disparity in the gene-dose effect by two susceptible DPB1 alleles may be attributable to the difference between the susceptible (36 A and 55 A) and resistant (8L, 9F, 11G, 57E and 76M) residue-combination consisting of DPbeta anchor pocket for antigenic peptide-binding. These results implied that the HLA-DP molecules with specificity pocket appropriate for HCV antigen(s) might confer the progressive process of HCM among the HCV-infected individuals.

Mao-to Prolongs the Survival of and Reduces TNF-alpha Expression in Mice with Viral Myocarditis

Goal of this study was to evaluate effects of Mao-to on development of myocarditis induced by encephalomyocarditis (EMC) virus in mice. Mice were randomly divided into five groups. Group N included uninfected controls (n = 18), while group A, B and C underwent intraperitoneal injection of EMC virus. Group A was administered oral saline from day 0 to day 4. Group B was administered oral Mao-to (500 mg⁻¹ kg⁻¹ day⁻¹) from day 0 to day 4. Group C was administered Mao-to from day 2 to day 6. Group D was administered Mao-to from day 5 to day 10. Treated mice were followed for survival rates during 2 weeks after infection. Body weight (BW) and organ weights including heart (HW), lungs, thymus and spleen were examined on days 4, 6 and 14. Survival rate of group C (36.4%) was significantly improved compared with group A, B or D (0% of each, P < 0.05). HW and HW/BW ratio in group C was significantly (P < 0.05) lower than those in group A, B or D. Viral titers of hearts were significantly different among groups A, B and C. Cardiac expression in tumor necrosis factor-α (TNF-α) was significantly reduced in group C in comparison with group A, B or D on day 6 by immunohistochemical study. Administration of Mao-to starting on day 2 improves mortality resulting from viral myocarditis in mice with reduced expression of cardiac TNF-α. These findings suggest that timing of Mao-to is crucial for preventing cardiac damage in mice with viral myocarditis.

Improved exercise capacity and reduced systemic inflammation after adenoviral-mediated SERCA-2a gene transfer

BACKGROUND

We hypothesized that sarcoplasmic reticulum Ca2+ ATPase pump (SERCA-2a) gene delivery would have beneficial effects upon exercise capacity and markers of inflammation in the setting of heart failure.

MATERIALS AND METHODS

A pressure-overload model of experimental heart failure was used in rats. Following a decrease in fractional shortening of >or=25%, animals underwent intracoronary adenoviral-mediated gene transfection using SERCA-2a. Heart failure animals were randomized to receive the SERCA-2a gene, the beta galactosidase (control) gene, or followed without any further intervention. Exercise and hemodynamic testing were performed, and myocardial and systemic markers of inflammation were assayed after 7 and 21 d.

RESULTS

Animals receiving Ad.SERCA-2a showed an increase in exercise tolerance (499.0 +/- 14.9 versus 312.8 +/- 10.5 s, P < 0.0001) relative to Ad.Gal group. Groups treated with Ad.SERCA-2a had significantly decreased serum levels of the inflammatory markers interleukin-1, interleukin-6, and tumor necrosis factor-alpha compared with Ad.Gal-treated animals. Serum levels of atrial natriuretic peptide were decreased in animals receiving Ad.SERCA-2a compared with animals receiving Ad.Gal at day 7 (0.35 +/- 0.03 versus 0.52 +/- 0.11 pg/mL, P = 0.001). Myocardial levels of the proapoptotic protein bax were reduced in Ad.SERCA-2a -treated animals compared with those receiving Ad.Gal at day 7 (protein level/actin: 0.24 +/- 0.05 versus 0.33 +/- 0.04, P = 0.04) and day 21 (protein level/actin: 0.61 +/- 0.04 versus 0.69 +/- 0.01, P = 0.001).

CONCLUSIONS

Genetic modulation of heart failure using the SERCA-2a gene was associated with improvement in cardiac function and exercise capacity as well as improvements in heart-failure associated inflammatory markers.

Results of a non-specific immunomodulation therapy in chronic heart failure (ACCLAIM trial): a placebo-controlled randomised trial

BACKGROUND

Evidence suggests that inflammatory mediators contribute to development and progression of chronic heart failure. We therefore tested the hypothesis that immunomodulation might counteract this pathophysiological mechanism in patients.

METHODS

We did a double-blind, placebo-controlled study of a device-based non-specific immunomodulation therapy (IMT) in patients with New York Heart Association (NYHA) functional class II-IV chronic heart failure, left ventricular (LV) systolic dysfunction, and hospitalisation for heart failure or intravenous drug therapy in an outpatient setting within the past 12 months. Patients were randomly assigned to receive IMT (n=1213) or placebo (n=1213) by intragluteal injection on days 1, 2, 14, and every 28 days thereafter. Primary endpoint was the composite of time to death from any cause or first hospitalisation for cardiovascular reasons. The study continued until 828 primary endpoint events had accrued and all study patients had been treated for at least 22 weeks. Analysis was by intention to treat. This study is registered with ClinicalTrials.gov, number NCT00111969.

FINDINGS

During a mean follow-up of 10.2 months, there were 399 primary events in the IMT group and 429 in the placebo group (hazard ratio 0.92; 95% CI 0.80-1.05; p=0.22). In two prespecified subgroups of patients--those with no history of previous myocardial infarction (n=919) and those with NYHA II heart failure (n=689)--IMT was associated with a 26% (0.74; 0.57-0.95; p=0.02) and a 39% (0.61; 95% CI 0.46-0.80; p=0.0003) reduction in the risk of primary endpoint events, respectively.

INTERPRETATION

Non-specific immunomodulation may have a role as a potential treatment for a large segment of the heart failure population, which includes patients without a history of myocardial infarction (irrespective of their functional NYHA class) and patients within NYHA class II.

Ccr1 deficiency reduces inflammatory remodelling and preserves left ventricular function after myocardial infarction

Myocardial necrosis triggers inflammatory changes and a complex cytokine cascade that are only incompletely understood. The chemokine receptor CCR1 mediates inflammatory recruitment in response to several ligands released by activated platelets and up-regulated after myocardial infarction (MI). Here, we assess the effect of CCR1 on remodelling after MI using Ccr1-deficient (Ccr1^−/−) mice. MI was induced in Ccr1^−/− or wild-type mice by proximal ligation of the left anterior descending (LAD). Mice were sacrificed and analysed at day 1, 4, 7, 14 and 21 after MI. While initial infarct areas and areas at risk did not differ between groups, infarct size increased to 20.6±8.4% of the left ventricle (LV) in wild-type mice by day 21 but remained at 11.2±1.2% of LV (P<0.05) in Ccr1^−/− mice. This attenuation in infarct expansion was associated with preserved LV function, as analysed by isolated heart studies according to Langendorff. Left ventricular developed pressure was 84.5±19.8 mmHg in Ccr1^−/− mice compared to 49.0±19.7 mmHg in wild-type mice (P<0.01) and coronary flow reserve was improved in Ccr1^−/− mice. An altered post-infarct inflammatory pattern was observed in Ccr1^−/− mice characterized by diminished neutrophil infiltration, accelerated monocyte/lymphocyte infiltration, decreased apoptosis, increased cell proliferation and earlier myofibroblast population in the infarcted tissue. In conclusion, functional impairment and structural remodelling after MI is reduced in the genetic absence of Ccr1 due to an abrogated early inflammatory recruitment of neutrophils and improved tissue healing, thus revealing a potential therapeutic target.

Candesartan improves myocardial damage in obese mice with viral myocarditis and induces cardiac adiponectin

PURPOSE

To clarify the mechanism of the effects of angiotensin II receptor type 1 antagonist, candesartan, upon cardiac adiponectin in the combination of myocarditis with obesity, we examined obese KKAy mice with acute viral myocarditis treated by candesartan and investigated cardiac adiponectin regulation.

METHODS

Mice were divided into candesartan early treatment group (Can-early) receiving orally candesartan at daily dose of 10 mg/kg 7 days starting before viral inoculation and then 7 days; candesartan late treatment group (Can-late) or vehicle (Vehicle) receiving candesartan starting simultaneously with viral inoculation and then 7 days. Encephalomyocarditis virus was used to induce the acute viral myocarditis. Differences in myocardial damages, serum adiponectin and myocardial expression of adiponectin, tumor necrosis factor-alpha (TNF-alpha), CCAAT/enhancer binding proteinalpha (C/EBPalpha) and peroxisome proliferator-activated receptor gamma (PPAR-gamma) and nuclear factor-kappaB (NF-kappaB) mRNA among three groups were determined on days 0, 4 and 7 after viral inoculation.

RESULTS

Mice in Can-early and Can-late groups showed reduced myocardial necrosis and cellular infiltration as compared with those in the Vehicle. On day 4 the circulating adiponectin levels were significantly higher in Can-early than those in Vehicle. Mice in Vehicle had significantly reduced in myocardial adiponectin mRNA after viral myocarditis. Cardiac adiponectin mRNA was significantly higher in Can-early and in Can-late than in Vehicle on days 4 and 7. Cardiac C/EBPalpha in Can-early and Can-early groups was significantly increased on day 4. Myocardial NF-kappaB and TNF-alpha mRNA in Can-early and Can-late groups were significantly reduced on day 7.

CONCLUSION

Candesartan treatment improved myocardial injury in obese mice with acute viral myocarditis and induced expression of cardiac adiponectin with the induction of C/EBPalpha as well as the reduction of cardiac NF-kappaB and TNF-alpha.