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)

Pyruvate, a metabolic product of glycolysis and an oxidizable fuel in myocardium, increases cardiac mechanical performance and energy reserves, especially when supplied at supraphysiological concentrations. The inotropic effects of pyruvate are most impressive in hearts that have been reversibly injured (stunned) by ischemia/reperfusion stress. Glucose appears to be an essential co-substrate for pyruvate's salutary effects in stunned hearts, but other fuels including lactate, acetate, fatty acids, and ketone bodies produce little or no improvement in postischemic function over glucose alone. In contrast to pharmacological inotropism by catecholamines, metabolic inotropism by pyruvate increases cardiac energy reserves and bolsters the endogenous glutathione antioxidant system. Pyruvate enhancement of cardiac function may result from one or more of the following mechanisms: increased cytosolic ATP phosphorylation potential and Gibbs free energy of ATP hydrolysis, enhanced sarcoplasmic reticular calcium ion uptake and release, decreased cytosolic inorganic phosphate concentration, oxyradical scavenging via direct neutralization of peroxides and/or enhancement of the intracellular glutathione/NADPH antioxidant system, and/or closure of mitochondrial permeability transition pores. This review aims to summarize evidence for each of these mechanisms and to consider the potential utility of pyruvate as a therapeutic intervention for clinical management of cardiac insufficiency.
 ...
PMID:Pyruvate: metabolic protector of cardiac performance. 1065 16

Increased reactive oxygen species (ROS) production is implicated in the pathophysiology of left ventricular (LV) hypertrophy and heart failure. However, the enzymatic sources of myocardial ROS production are unclear. We examined the expression and activity of phagocyte-type NADPH oxidase in LV myocardium in an experimental guinea pig model of progressive pressure-overload LV hypertrophy. Concomitant with the development of LV hypertrophy, NADPH-dependent O2- production in LV homogenates, measured by lucigenin (5 micro mol/L) chemiluminescence or cytochrome c reduction assays, significantly and progressively increased (by approximately 40% at the stage of LV decompensation; P<0.05). O2- production was fully inhibited by diphenyleneiodonium (100 micromol/L). Immunoblotting revealed a progressive increase in expression of the NADPH oxidase subunits p22(phox), gp91(phox), p67(phox), and p47(phox) in the LV hypertrophy group, whereas immunolabeling studies indicated the presence of oxidase subunits in cardiomyocytes and endothelial cells. In parallel with the increase in O2- production, there was a significant increase in activation of extracellular signal-regulated kinase 1/2, extracellular signal-regulated kinase 5, c-Jun NH2-terminal kinase 1/2, and p38 mitogen-activated protein kinase. These data indicate that an NADPH oxidase expressed in cardiomyocytes is a major source of ROS generation in pressure overload LV hypertrophy and may contribute to pathophysiological changes such as the activation of redox-sensitive kinases and progression to heart failure.
 ...
PMID:Activation of NADPH oxidase during progression of cardiac hypertrophy to failure. 1236 50

Despite advances in treatment, chronic congestive heart failure carries a poor prognosis and remains a leading cause of cardiovascular death. Accumulating evidence suggests that reactive oxygen species (ROS) play an important role in the development and progression of heart failure, regardless of the etiology. Under pathophysiological conditions, ROS have the potential to cause cellular damage and dysfunction. Whether the effects are beneficial or harmful will depend upon site, source and amount of ROS produced, and the overall redox status of the cell. All cardiovascular cell types are capable of producing ROS, and the major enzymatic sources in heart failure are mitochondria, xanthine oxidases and the nonphagocytic NADPH oxidases (Noxs). As well as direct effects on cellular enzymatic and protein function, ROS have been implicated in the development of agonist-induced cardiac hypertrophy, cardiomyocyte apoptosis and remodelling of the failing myocardium. These alterations in phenotype are driven by redox-sensitive gene expression, and in this way ROS may act a potent intracellular second messengers. Recent experimental studies have suggested a possible causal role for increased ROS in the development of contractile dysfunction following myocardial infarction and pressure overload, however the precise contribution of different cellular and enzymatic sources involved remain under investigation.
 ...
PMID:Oxidative stress and heart failure. 1272 52

Energostim is a combined drug comprising a mixture of nicotinamide adenine dinucleotide (0.5 mg), cytochrome C (10 mg), and inosine (80 mg), representing antihypoxant and antioxidant of direct action in one ampule. After pretreatment and subsequent 3-day energostim therapy of animals with 3-day toxico-allergic myocarditis (3d-TAM), the ECG was free of any rhythm disorders and showed evidence of improved conduction, restoration of the normal form of T-wave and the position of ST segment, while the content of myofibrillar fraction of creatine phosphokinase and toxic products of disturbed metabolism (degree of endotoxemia) decreased to the upper normal level. Under the action of energostim, neither pressure nor the maximum rate of pressure buildup in the left ventricle are reduced (as they do upon 3d-TAM); neither systolic and diastolic functions are disturbed, nor their coordination (r = 0.79 between dP/dtmin and dP/dtmax, p < 0.01). The restoration of contractile activity and maximum rate of relaxation of myocardial microfibrils during 3d-TAM is accompanied by an increase in the content of adenyl nucleotides, in the ATP/ADP, ADP/AMP, NAD/NADH, and NADP/NADPH ratios, and in the cytosol phosphorylation potential. The energostim-induced improvement in the energy supply system are accompanied by restoration of the ability of sarcoplasmic reticulum to efflux Ca2+. Thus, it is demonstrated that the effect of energostim is related to its ability to actively participate in intracell metabolic processes in myocardium, abolish necrotic changes and endotoxicosis, and restore homeostasis in the systems responsible for the contraction--relaxation process (thus preventing from the development of dysfunction of the left ventricle and the heart failure).
 ...
PMID:[Cardioprotective effect of energostim in toxic allergic myocarditis]. 1518 54

NAD(P)H oxidase contributes to the pathogenesis of cancer and cardiovascular diseases such as hypertension, atherosclerosis, restenosis, cardiac hypertrophy and heart failure. Plumbagin, a plant-derived naphthoquinone, has been shown to exert anticarcinogenic and anti-atherosclerosis effects in animals. However, the molecular mechanisms underlying these effects remain unknown. It is possible that the beneficial effect of plumbagin is due to the inhibition of NAD(P)H oxidase. Human embryonic kidney 293 (HEK293) and brain tumour LN229 cells express mainly Nox-4, a renal NAD(P)H oxidase. We have examined the effect of plumbagin on Nox-4 activity in HEK293 and LN229 cells using lucigenin-dependent chemiluminescence assay. Plumbagin inhibited the activity of Nox-4 in a time- and dose-dependent manner in HEK293 and LN229 cells. Production of superoxide in HEK293 cells was inhibited by diphenyleneiodonium (DPI), a NAD(P)H oxidase inhibitor. The superoxide production in HEK293 cells was NADPH- and NADH-dependent indicating that the superoxide was generated by a NAD(P)H oxidase in HEK293 cells, but not by the redox-cycling of lucigenin. Furthermore, plumbagin inhibited the superoxide production in Nox-4 transfected COS-7 cells. These results indicated that plumbagin directly interacted with Nox-4 and inhibited its activity.
 ...
PMID:Inhibition of Nox-4 activity by plumbagin, a plant-derived bioactive naphthoquinone. 1563 99

Refracterin therapy of patients with chronic heart failure caused by coronary heart disease and postinfarction cardiosclerosis markedly promoted improvement in the pulmonary and systemic circulation in comparison with patients receiving traditional therapy. The mean functional class of chronic cardiac failure decreased by 43% under the effect of refracterin vs. 27% decrease in the group receiving traditional therapy. After 1-month refracterin course the end-systolic and end-diastolic sizes of the left ventricle decreased by 12 and 7%, respectively, ejection fraction increased by 7.2% in comparison with the initial level, total oxidant activity and MDA content in the plasma decreased significantly, while total antioxidant activity, catalase and SOD activities, cytochrome C, NADH, and NADPH levels increased. The prooxidant-antioxidant system was shifted towards antioxidants, which attests to activation of the defense and adaptive mechanisms after administration of refracterin, which is especially important in elderly patients with initially decreased reserve potentialities of the antioxidant defense system.
 ...
PMID:Efficiency and mechanisms of the antioxidant effect of standard therapy and refracterin in the treatment of chronic heart failure in elderly patients with postinfarction cardiosclerosis. 1566 59

It is now established that the brain possesses a local renin-angiotensin system and that angiotensin II exerts multiple actions in the nervous system, including regulation of striatal dopamine release. Furthermore, angiotensin activates NADPH-dependent oxidases, which are a major source of superoxide, and angiotensin-converting enzyme inhibitors, commonly used in the treatment of hypertension and chronic heart failure, have shown antioxidant properties in several tissues. Oxidative stress is a key contributor to the pathogenesis and progression of Parkinson's disease. In the present study, we treated rats with intraventricular injections of the dopaminergic neurotoxin 6-hydroxydopamine and subcutaneous injections of the angiotensin-converting enzyme inhibitor Captopril to study the possible neuroprotective effect of the latter on the dopaminergic system and on 6-hydroxydopamine-induced oxidative stress. Rats treated with Captopril and 6-hydroxydopamine showed significantly less reduction in the number of dopaminergic neurons (i.e., immunoreactive to tyrosine hydroxylase) in the substantia nigra and in the density of striatal dopaminergic terminals than 6-hydroxydopamine-lesioned rats not treated with Captopril. In addition, Captopril reduced the levels of major oxidative stress indicators (i.e., lipid peroxidation and protein oxidation) in the ventral midbrain and the striatum of 6-hydroxydopamine-lesioned rats. Our results suggest that angiotensin-converting enzyme inhibitors may be useful for treatment of Parkinson's disease and that further investigation should focus on the neuroprotective capacity of these compounds.
 ...
PMID:Angiotensin-converting enzyme inhibition reduces oxidative stress and protects dopaminergic neurons in a 6-hydroxydopamine rat model of Parkinsonism. 1601 98

Intracellular ROS (reactive oxygen species) such as superoxide and H2O2 have been increasingly appreciated to have a role in endothelial pathophysiology. Of the several sources within the vasculature, a family of multi-subunit NADPH oxidases appears to be a predominant contributor of endothelial superoxide. More importantly, this enzyme system is activated by numerous stimuli and is involved in triggering diverse intracellular signalling pathways ('redox-sensitive' signalling pathways) that have a central role in conditions such as endothelial activation and inflammation, cell growth, apoptosis and hypertrophy. Furthermore, NADPH oxidase-derived superoxide contributes to the impairment of endothelium-dependent vasodilatation by inactivating nitric oxide; the resultant endothelial dysfunction is implicated in the pathophysiology of diseases such as atherosclerosis, hypertension, diabetic vasculopathy and heart failure. A detailed understanding of the regulation of NADPH oxidases and their modulation and downstream effects may define novel therapeutic targets for cardiovascular disease prevention and treatment in the clinical setting, in contrast with global antioxidant therapy which has to date been disappointing.
 ...
PMID:NADPH oxidase and endothelial cell function. 1610 42

Human cardiac fibroblasts are the main source of cardiac fibrosis associated with cardiac hypertrophy and heart failure. Transforming growth factor-beta1 (TGF-beta1) irreversibly converts fibroblasts into pathological myofibroblasts, which express smooth muscle alpha-actin (SM alpha-actin) de novo and produce extracellular matrix. We hypothesized that TGF-beta1-stimulated conversion of fibroblasts to myofibroblasts requires reactive oxygen species derived from NAD(P)H oxidases (Nox). We found that TGF-beta1 potently upregulates the contractile marker SM alpha-actin mRNA (7.5+/-0.8-fold versus control). To determine whether Nox enzymes are involved, we first performed quantitative real time polymerase chain reaction and found that Nox5 and Nox4 are abundantly expressed in cardiac fibroblasts, whereas Nox1 and Nox2 are barely detectable. On stimulation with TGF-beta1, Nox4 mRNA is dramatically upregulated by 16.2+/-0.8-fold (n=3, P<0.005), whereas Nox5 is downregulated. Small interference RNA against Nox4 downregulates Nox4 mRNA by 80+/-5%, inhibits NADPH-driven superoxide production in response to TGF-beta1 by 65+/-7%, and reduces TGF-beta1-induced expression of SM alpha-actin by 95+/-2% (n=6, P<0.05). Because activation of small mothers against decapentaplegic (Smads) 2/3 is critical for myofibroblast conversion in response to TGF-beta1, we also determined whether Nox4 affects Smad 2/3 phosphorylation. Depletion of Nox4 but not Nox5 inhibits baseline and TGF-beta1 stimulation of Smad 2/3 phosphorylation by 75+/-5% and 68+/-3%, respectively (n=7, P<0.0001). We conclude that Nox 4 mediates TGF-beta1-induced conversion of fibroblasts to myofibroblasts by regulating Smad 2/3 activation. Thus, Nox4 may play a critical role in the pathological activation of cardiac fibroblasts in cardiac fibrosis associated with human heart failure.
 ...
PMID:NAD(P)H oxidase 4 mediates transforming growth factor-beta1-induced differentiation of cardiac fibroblasts into myofibroblasts. 1625 16

Chronic heart failure, secondary to left ventricular hypertrophy or myocardial infarction, is a condition with increasing morbidity and mortality. Although the mechanisms underlying the development and progression of this condition remain a subject of intense interest, there is now growing evidence that redox-sensitive pathways play an important role. This article focuses on the involvement of reactive oxygen species derived from a family of superoxide-generating enzymes, termed NADPH oxidases (NOXs), in the pathophysiology of ventricular hypertrophy, the accompanying interstitial fibrosis and subsequent heart failure. In particular, the apparent ability of the different NADPH oxidase isoforms to define the response of a cell to a range of physiological and pathophysiological stimuli is reviewed. If confirmed, these data would suggest that independently targeting different members of the NOX family may hold the potential for therapeutic intervention in the treatment of cardiac disease.
 ...
PMID:NADPH oxidase-derived reactive oxygen species in cardiac pathophysiology. 1632 3


1 2 3 4 5 6 7 8 Next >>