Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0018801 (heart failure)
 72,216 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The observed increased susceptibility of patients with fulminant hepatic failure for local and systemic infections has been hypothesized to be due to a failure for the hepatic clearance function and subsequent leaking of endogenous endotoxins into the systemic circulation. However, experimental evidence for such a systemic inflammation during liver failure due to endogenous endotoxemia is lacking. Therefore, we designed a study to clarify whether circulating endotoxins due to liver failure could lead to the development of systemic inflammations. In a rat model for liver failure induced by a two-thirds partial hepatectomy, we evaluated the course of circulating tumor necrosis factor and interleukin-6, changes in blood chemistry and hemodynamics, and histopathological changes in the lungs. Partially hepatectomized animals, but not sham-operated animals, demonstrated cardiac failure, increased levels of creatinin and urea, metabolic acidosis, high plasma levels of tumor necrosis factor and interleukin-6, and an influx of PMNs in the lungs-together indicating the development of a systemic inflammatory response. Continuous infusion of recombinant N-terminal bactericidal/permeability-increasing protein (rBPI23), a well described endotoxin-neutralizing protein, prevented these inflammatory reactions. Ex vivo experiments with rat plasma samples confirmed the presence of circulating endotoxins in partially hepatectomized rats as opposed to those treated with rBPI23. Thus, our results indicate that the early phase of liver failure induces a systemic inflammatory response triggered by circulating endotoxins, which can be prevented by perioperative infusion of rBPI23.
 ...
PMID:Liver failure induces a systemic inflammatory response. Prevention by recombinant N-terminal bactericidal/permeability-increasing protein. 748 5

Proinflammatory cytokines are capable of modulating cardiovascular function by a variety of mechanisms. These cytokines are elevated in patients with severe heart failure, but changes in mild or moderate heart failure have not been reported. Therefore, simultaneous arterial and coronary sinus concentrations of interleukin-1alpha, soluble interleukin-2 receptor, interleukin-6, and tumor necrosis factor-alpha were measured in 78 patients with New York Heart Association functional class II to IV heart failure and compared with 17 healthy volunteers. Concentrations of interleukin-1alpha, soluble interleukin-2 receptor, and interleukin-6 were determined by a "sandwich" enzyme-linked immunosorbent assay and tumor necrosis factor-alpha by tissue culture technique. There were no statistical differences in interleukin-1alpha, soluble interleukin-2 receptor, or tumor necrosis factor-alpha concentrations in mild to moderate heart failure versus control subjects. Interleukin-6 was significantly elevated, 75 +/- 16 versus 0.4 +/- 0.4pg/ml (p = 0.002). Cytokine concentrations did not differ by heart failure etiology. Paired arterial and coronary sinus concentrations were not significantly different. Soluble interleukin-2 receptor concentrations were significantly correlated with New York Heart Association functional class (r = 0.59, p = 0.04) and negatively associated with exercise tolerance time (r = -0.59, p = 0.007). Thus, interleukin-6 is significantly elevated in mild or moderate heart failure.
 ...
PMID:Circulating concentrations of proinflammatory cytokines in mild or moderate heart failure secondary to ischemic or idiopathic dilated cardiomyopathy. 865 Nov 23

To ascertain whether elevated levels of circulating proinflammatory cytokines in patients with advanced heart failure are due to congestive heart failure or due to cachexia or infection complicating heart failure, we measured prospectively plasma concentrations of tumor necrosis factor-alpha (TNF-alpha), interleukin-1 beta (IL-1 beta), interleukin 2 (IL-2), and interleukin-6 (IL-6) in 12 patients with mitral stenosis with moderate congestive heart failure, but not with cachexia or infection. Blood samples were obtained from the peripheral vein and right and left atria of the patients during percutaneous mitral valvuloplasty. Levels of TNF-alpha, IL-1 beta, IL-2, and IL-6 in the plasma form the peripheral vein and right and left atria of these patients were not elevated compared with those from the peripheral vein of a control group of 10 normal subjects. On the other hand, plasma levels of TNF-alpha but not IL-1 beta, IL-2 or IL-6, were elevated in 4 of 9 patients with congestive heart failure complicated with cachexia and/or infection. Our results suggest that proinflammatory cytokine levels are not elevated in congestive heart failure uncomplicated with cachexia or infection.
 ...
PMID:Plasma cytokine levels in cardiac chambers of patients with mitral stenosis with congestive heart failure. 890 73

Proinflammatory cytokines have been implicated in the pathophysiology of chronic heart failure. We determined mixed venous levels of interleukin-6 (IL6) in 18 heart transplant candidates before, 1, 4, and 24 h after initiation of dobutamine infusion (3 micrograms/kg/min) during hemodynamic evaluation. During the first 4 h of dobutamine, systemic vascular resistance decreased (1358 to 1024 dyn x s x cm-5, P = 0.01) while cardiac index (2.3 to 2.9 l/min/m2, P = 0.008) increased. Both returned to baseline after 24 h. IL6 was elevated at baseline compared to age-matched controls (1.5 (0/4.3) vs. 0 (0/0.5) P = 0.003). There was an increase in IL6 from 1.5 (0/4.3) to 3.6 (0.3/5.3) pg/ml after 24 h (P = 0.04). We found higher IL6 levels in the sicker half of patients as defined by pulmonary capillary wedge pressure > 24 mmHg (P = 0.005), mean pulmonary arterial pressure > or = 35 mmHg (P = 0.01), right atrial pressure > 13 mmHg (P = 0.02), and heart rate > or = 87/min (P = 0.02) as well as mean arterial pressure < 82 mmHg (P = 0.005). In conclusion, in this pilot study IL6 correlates with the severity of chronic heart failure during low dose dobutamine infusion.
 ...
PMID:Interleukin-6 correlates with hemodynamic impairment during dobutamine administration in chronic heart failure. 901 64

We have previously proposed that pro-inflammatory cytokines and nitric oxide (NO) contributed to reversible myocardial depression in patients with sepsis and congestive heart failure. Sepsis and heart failure are also associated with refractoriness to beta-adrenoceptor agonists. Therefore, the chronotropic effects of cytokines and the NO synthase inhibitor, NG-methyl-L-arginine (NMA), on beta-adrenoceptor stimulation of neonatal cardiac myocytes were studied. Tumor necrosis factor alpha, interleukin-1 beta and interleukin-6 but not interleukin-4 or interleukin-5 significantly enhanced spontaneous beating rates compared to untreated myocytes in serum-free media for 48 h (P < 0.01; n = 12 for each). NMA also significantly enhanced spontaneous beating rates (P < 0.01; n = 12 for each). Only interleukin-1 beta treatment resulted in significant nitrite production, immunohistochemical staining for inducible nitric oxide synthase and detection of inducible NO synthase messenger RNA by reverse transcriptase-polymerase chain reaction (RT-PCR). However, tumor necrosis factor alpha, interleukin-1 beta, interleukin-6, and NMA each completely blocked the positive chronotropic effects of the beta-adrenoceptor agonist, isoproterenol (P < 0.01; n = 12 for each). These findings are most consistent with an inducible NO synthase-independent effect of cytokines and NMA on the chronotropic responses of neonatal cardiac myocytes to beta-adrenoceptor stimulation. This effect of cytokines and NMA on adrenergic signaling may involve a myocardial constitutive NO synthase or an NO-independent mechanism.
 ...
PMID:Cytokines and nitric oxide synthase inhibitor as mediators of adrenergic refractoriness in cardiac myocytes. 905 50

In a group of patients with New York Heart Association class IV heart failure, significant relations between interleukin-6 and tumor necrosis factor-alpha, and between levels of both interleukin-6 and tumor necrosis factor-alpha and plasma levels of norepinephrine were observed. The present study also demonstrates that in patients with heart failure, elevated levels of tumor necrosis factor-alpha and interleukin-6 may be present even without cachexia.
 ...
PMID:Circulating interleukin-6 in severe heart failure. 911 81

Cytokines are proteins with pleiotropic biological effects, but the pathophysiologic role of cytokine inhibitors in advanced cardiac disease remains unclear. We assessed the levels of tumor necrosis factor (TNF)-alpha and its soluble receptors I (sTNF-RI) and II (sTNF-RII), soluble interleukin-1 receptor antagonist (sIL-1 Ra), and interleukin-6 soluble receptor (IL-6 sR) in sera from 11 patients with severe chronic congestive heart failure (mean left ventricular ejection fraction 19 +/- 6%; mean symptom-limited oxygen consumption 13 +/- 4 ml/min per kg) and 11 healthy volunteers. The serum concentrations of TNF, sTNF-RI, and sIL-1 Ra, but not of sTNF-RII and IL-6 sR, were significantly increased in heart failure patients. Importantly, their symptom-limited oxygen consumption was strongly associated with both sTNF-RI (R = -0.68, p = 0.04) and sIL-1 Ra (R = -0.77, p = 0.01). These results suggest that cytokine inhibitors from different receptor families may be involved in functional disability, a characteristic feature in patients with severe congestive heart failure. Understanding the response of cytokine inhibitors to heart failure might have therapeutic value as interventions against cytokines become available.
 ...
PMID:Cytokine inhibitors in patients with heart failure and impaired functional capacity. 929 4

Cardiac hypertrophy and heart failure are frequently accompanied by elevated plasma levels of tumor necrosis factor alpha (TNF alpha), the pathogenetic relevance of this finding being a matter of debate. In human acute septic cardiomyopathy, on the other hand, the negative inotropic impact of TNF alpha on the heart is well documented and frequently ascribed to the induction of inducible nitric oxide (NO) synthase (iNOS) and an enhanced production of NO in the heart. Yet the present study presents evidence that in cardiomyocytes TNF alpha in non-toxic concentrations specifically depresses contractile performance independent of NO. In spontaneously beating neonatal rat cardiomyocytes, TNF alpha in a low, pathophysiologically relevant concentration (10 U/ml, 1-3 days) does not alter basal pulsation amplitude, but blocks alpha- and beta-adrenoceptor-stimulated increase in contractility and beating irregularity and impairs the impact of high extracellular calcium on contractile performance. However, this low TNF alpha-concentration does not suffice to induce iNOS - documented by reverse transcriptase polymerase chain reaction - or enhance nitrite concentrations in the cell culture supernatants as a measure of cellular NO production, neither in the presence nor absence of dexamethasone (0.1 micro M). Only in high concentration - the specific proinflammatory action being documented by an enhanced release of interleukin-6 from cardiomyocytes - TNF alpha (1000 U/mol; 6, 24 h) weakly induces the mRNA for iNOS, with a consecutive moderate rise in cellular nitrite production. TNF alpha-incubation (10-1000 U/ml) does not alter the morphological appearance of the cells displayed by phase contrast microscopy or evoke gross cytotoxicity.
 ...
PMID:Tumor necrosis factor alpha (TNF alpha) is cardiodepressant in pathophysiologically relevant concentrations without inducing inducible nitric oxide-(NO)-synthase (iNOS) or triggering serious cytotoxicity. 940 66

Endothelin-1 (ET-1) enhances the biosynthesis of interleukin-6 (IL-6) in endothelial cells and bone marrow-derived stromal cells of the rat. This study investigates (i) whether ET-1 stimulates the formation of tumour necrosis factor alpha (TNF alpha) or interferon-gamma (IFN gamma) in cultured macrophages or in the anaesthetized rat. Incubation of J774.2 macrophages with ET-1 (0.001-1 microM) caused a concentration- and time-dependent increase in the concentration of TNF alpha, but not of IFN gamma, in the culture medium. The increase in TNF alpha caused by stimulation of J774.2 macrophages was abolished by pretreatment of cells with (i) the protein synthesis inhibitor cycloheximide, (ii) with the selective ETA-receptor antagonists BQ-123 or BQ-485 (but not the selective ETB-receptor antagonist BQ-788), (iii) the tyrosine kinase inhibitors genistein or tyrphostin AG126, or (iv) with the glucocorticoid, dexamethasone. The inhibition by dexamethasone of the formation of TNF alpha by cells activated with ET-1 is not due to the formation of lipocortin-1 (LC1), as it was not reduced by a monoclonal antibody against LC1. Systemic administration (i.v.) of ET-1 (1 nmol.kg-1) to anaesthetized rats caused a rapid and sustained (maximum: 45 min; return to baseline: within 180 min) rise in the plasma levels of TNF alpha. This is the first demonstration that ET-1 can release proinflammatory cytokines in vitro and in vivo. The generation of TNF alpha caused by ET-1 involves (in sequence) the (i) activation of ETA-receptors, (ii) activation of tyrosine kinase resulting in the phosphorylation of intracellular proteins, (iii) the activation of, hitherto, unknown transcription factors, finally resulting in (iv) transcription and translation of the TNF alpha gene. The generation of TNF alpha by cells activated with ET-1 points to a pro-inflammatory role of ET-1 in diseases associated with local (e.g. atherosclerosis, heart failure) or systemic inflammation (circulatory shock), which are associated with high ET-1 plasma levels.
 ...
PMID:Endothelin-1 stimulates the biosynthesis of tumour necrosis factor in macrophages: ET-receptors, signal transduction and inhibition by dexamethasone. 944 16

In situations of depressed myocardial function, the role of immunological mechanisms has been studied recently. In different pathophysiological situations, such as chronic heart failure, open heart surgery with extracorporal circulation, cardiac transplantation, myocardial infarction and angina pectoris, patterns have been described with elevation of proinflammatory cytokines, such as tumor necrosis factor-alpha, interleukin-1, interleukin-6, and reversible myocardial dysfunction, which may represent a final common pathway. The available data suggest a modulation of important determinants of pump function, i.e., contractility, preload, afterload, and heart rate, by cytokines. Potential mechanisms include the beta-adrenoceptor- and nitric oxide pathway, as well as a direct impact on intracellular calcium homeostasis. Interventional strategies based on this understanding are beginning to emerge.
 ...
PMID:[Proinflammatory cytokines and cardiac pump function]. 945 46


1 2 3 4 5 6 7 8 9 10 Next >>