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)

Endothelium-dependent responses are depressed in coronary and peripheral blood vessels after the onset of pacing-induced heart failure in dogs and heart failure of various etiologies in humans. The present study was designed to examine whether these responses were due to decreases in the expression of endothelial cell NO synthase (ecNOS) and cyclooxygenase-1 (COX-1). After 1 month of left ventricular pacing, 8 mongrel dogs were monitored for heart failure as defined by clinical signs and left ventricular end diastolic pressures > 25 mm Hg. Total RNA and protein were isolated from endothelial cells scraped from the thoracic aorta and analyzed by Northern and Western blotting, respectively. Blots probed with 32P-labeled cDNAs for ecNOS and COX-1 were quantified densitometrically, and results were normalized against GAPDH or von Willebrand factor (vWF). In arbitrary units, the ratios of ecNOS to GAPDH were 2.66 +/- 0.77 (mean +/- SEM, n = 17) and 1.12 +/- 0.37 (n = 6 and the ratios of COX-1 to GAPDH were 1.52 +/- 0.52 and 0.56 +/- 0.15 before and after heart failure, respectively. These represent 56% to 64% (P < .05) reductions in ecNOS and COX-1 gene expression. There was no change in the ratios of either COX-1 or ecNOS to vWF. There was also a marked reduction in ecNOS protein after heart failure, estimated at 70%. A marked reduction in nitrite production, a measure of enzyme activity, from thoracic aortas in response to stimulation by either acetylcholine or bradykinin also occurred. To determine whether ecNOS and COX-1 could be independently regulated, an orally active NO-releasing agent, CAS 936, was given to 7 normal dogs for 7 days, and aortic ecNOS and COX-1 mRNAs were analyzed. The ratio of ecNOS to GAPDH was depressed by 52% (P < .05) in aortas from these dogs, whereas the ratio of COX-1 to GAPDH was unchanged. Similar results were found when data were normalized to vWF. These results suggest that at least two endothelial vasodilator gene products are reduced in heart failure, as opposed to a selective defect in NO synthase gene expression.
 ...
PMID:Reduced gene expression of vascular endothelial NO synthase and cyclooxygenase-1 in heart failure. 860 6

Recent studies have implicated angiotensin II (angiotensin) in the pathogenesis of cardiac hypertrophy and heart failure. Heart failure is associated with alterations in intracellular Ca2+ movements mediated by sarcolemmal (SL) and sarcoplasmic reticular (SR) membranes in cardiac myocytes. As it was suspected that alteration gene expression of proteins responsible for controlling transmembrane Ca2+ fluxes may contribute to loss of Ca2+ homeostasis in failing hearts, we undertook a study of the effect of angiotensin on the expression of some target genes in the myocardium. Specifically, we tested the effect of angiotensin on mRNA abundance of cardiac Ca(2+)-transport genes including SL Na+/Ca2+ exchange (EX), SR ryanodine receptor (RYR), and sarco(endo)plasmic reticulum Ca(2+)-ATPase (SERCA). The mRNA abundance of target gene was assessed by Northern blot assay in (i) direct hormonal stimulation of cultured isolated neonatal and adult rat myocytes and (ii) adult rat hearts after implantation of osmotic mini-pumps for delivery of hormone. In all experiments, Northern blot data were normalized using cDNA (Glyceraldehyde 3-phosphate dehydrogenase signal, GAPDH) hybridization to RNA samples. The results indicate that the ratios of EX/GAPDH, RYR/GAPDH, and SERCA2/GAPDH signals were decreased by 51.6%, 55.0%, and 49.4% respectively after neonatal cardiac myocytes were treated (24 h) with 10(-7) M angiotensin. These decreases were blocked completely by treatment with angiotensin subtype 1 (AT1) receptor antagonist (losartan), whereas angiotensin subtype 2 (AT2) receptor antagonist (PD123319) treatment had no effect on the angiotensin-mediated decrease in target gene mRNA abundance. In contrast, angiotensin had no effect on EX, RYR nor SERCA2 gene mRNA abundance in cultured adult myocytes. In a separate series of experiments wherein adult male Sprague-Dawley rats were infused with different dose of angiotensin for 3 days via osmotic mini-pump, we did not detect any alterations in mRNA abundance of cardiac EX/GAPDH, RYR/GAPDH or SERCA/GAPDH genes in either left or right ventricular samples. Thus our results indicate that, in neonatal rat myocytes, angiotensin affects SL and SR calcium transport gene expression by direct agonism of AT1-receptors. As the infusion of low and high dose angiotensin did not affect the expression of target genes in adult hearts, we suggest that the mechanisms for transduction of the angiotensin signaling in neonatal and adult myocytes may be different and may depend on the stage of development. We conclude that regulation of myocardial Ca(2+)-transport gene mRNA abundance by angiotensin may differ among neonatal and adult animals. Nonetheless, our finding with respect to neonatal preparation led us to believe that in neonatal myocytes, the mRNA abundance of SL Na+/Ca2+ exchange, SR ryanodine receptor, and SR Ca(2+)-ATPase are all decreased in response to stimulation by angiotensin.
 ...
PMID:Altered mRNA abundance of calcium transport genes in cardiac myocytes induced by angiotensin II. 876 48

The mammalian heart is normally well oxygenated and anaerobic glycolysis is extremely rare except for the production of extra ATP during extreme exercise like a marathon race. Anaerobic glycolysis plays a role when there is a serious impairment in coronary blood flow such as during heart attack and open heart surgery. The control of glycolysis in ischemic myocardial tissue appears to be extremely complex. During aerobic glycolysis, phosphofructokinase is the most important regulatory enzyme that controls the energy requirements of the cell. Under anaerobic conditions, however, glyceraldehyde-3-phosphate dehydrogenase becomes the key enzyme because it responds promptly to any changes in the essential supply of co-factors for oxidation. The conversion of pyruvate to acetyl CoA (aerobic metabolism) involves a series of chain reactions primarily catalyzed by pyruvate dehydrogenase complex which is situated at the cross roads between both aerobic and anaerobic glycolysis. It is important to remember that substrate utilization is carefully controlled by substrate availability. During aerobic metabolism, control mechanisms using fatty acids, lactate and glucose as energy substrates regulate the rate of ATP production according to energy demand. This precise mechanism is upset during ischemia and post-ischemic reperfusion for reasons discussed in this review. The demand for ATP can no longer be met by its supply because of severely reduced anaerobic glycolysis and significantly inhibited beta-oxidation of fatty acids. The impairment of bioenergetics is discussed in the context of several diseases such as cardiomyopathy, heart failure, diabetes, arrhythmias, cardiac surgery, heart-lung transplantation, and also in aging and oxidative stress. The regulation of energy metabolism in preconditioned heart is also discussed. Finally, methods used to preserve energy in ischemic myocardium are summarized and quantitation of the high-energy phosphates is discussed. This review challenges scientists to discover drugs which will stimulate energy supply during myocardial ischemia.
 ...
PMID:Bioenergetics, ischemic contracture and reperfusion injury. 880 94

Pressure overload on the heart is known to produce hypertrophy of cardiomyocytes and distinct changes in protein phenotype, including reduced expression of the gene for the sarcoplasmic reticulum (SR) Ca2+ATPase (SERCA2). In this study we have shown that the decrease in SERCA2 gene expression (normalized by poly(A)+ mRNA or 18 S rRNA) in rats with 8 wk of aortic constriction was prevented by treatment with etomoxir, an inhibitor of carnitine palmitoyltransferase 1. The reduction in steady-state mRNA levels for SR phospholamban (PLP) and Ca2+ release channel (CRC) in the pressure-overloaded animals was also prevented without any reduction in the extent of cardiac hypertrophy by treatment with etomoxir. Although no changes in mRNA levels for GAPDH were evident in rats with pressure overload, the expression of the alpha-skeletal actin was increased; this change was prevented by etomoxir. Similar beneficial effects of etomoxir treatment were also evident when the gene expression for SR SERCA2, PLP, and CRC in the hypertrophied heart was normalized with respect to mRNA for GAPDH. These results support the view that drugs such as etomoxir may increase the abundance of the mRNA for SR proteins in the hypertrophied heart and thus may prevent the transition of cardiac hypertrophy into heart failure.
 ...
PMID:Modification of sarcoplasmic reticulum gene expression in pressure overload cardiac hypertrophy by etomoxir. 883 44

Congestive heart failure is often associated with skeletal muscle abnormalities that contribute to early fatigue and acidosis. Up to the present time, however, the mechanisms responsible for these changes are unclear. Myocardial infarctions were produced by coronary ligation in adult Sprague-Dawley rats. At 20 weeks, 10 control rats, and 15 animals with heart failure [defined by elevated LVEDP (26.1 +/- 3.1 v 2.5 +/- 0.5 mmHg) and RV hypertrophy (300 +/- 21 g v 158 +/- 9 mg)] underwent in vivo measurements of total body, and soleus total protein and myosin heavy chain (MHC) synthesis by [3H]leucine constant infusion. Soleus muscle was also analysed for protein content, and MHC isoenzyme content by SDS-PAGE. Northern blotting also was used to determine levels of the mRNA's encoding type I, IIa, IIb, and IIx MHC, alpha-skeletal actin, COX III, SDH and GAPDH. Soleus muscles in heart failure rats were smaller than controls (112 +/- 6 v 126 +/- 5 mg) and the degree of atrophy was significant when corrected for body mass (0.38 +/- 0.02 v 0.46 +/- 0.02 mg/g. P = 0.007). Although there was no significant difference in plasma leucine flux (an index of whole-body protein synthesis), soleus muscle total and MHC synthesis was reduced in heart failure animals. Whereas the Type I MHC isoenzyme (beta MHC) was the only MHC detected in the soleus of control animals, type II MHC isoenzyme comprised 11.8 +/- 3.1% of the MHC in the heart failure group. Furthermore, steady-state mRNA levels encoding beta MHC were significantly depressed in the heart failure rats, where those encoding Types IIb and IIx MHC were increased. Steady-state mRNA levels of alpha-skeletal actin, cytochrome C oxidase (COX III) and succinate dehydrogenase (SDH) were also significantly depressed. This animal model of chronic heart failure is associated with quantitative and qualitative alterations in skeletal muscle gene expression that are similar to those reported in skeletal muscle of patients with chronic heart failure. The altered phenotype and impaired metabolic capacity may contribute to exercise intolerance in CHF.
 ...
PMID:Alterations in skeletal muscle gene expression in the rat with chronic congestive heart failure. 887 78

Myocardial angiotensin receptors of type 1 (AT1) are downregulated at the protein and mRNA levels in human heart failure. No data are available for the transplanted human heart, which frequently exhibits functional alterations. The aim of the present study was the quantitation of ventricular AT1 mRNA content in endomyocardial biopsies from patients after heart transplantation. For the determination of AT1 mRNA we used a novel quantitative reverse transcription polymerase chain reaction with low variance (6%) based on an internal AT1 cRNA standard, liquid-phase hybridization of polymerase chain reaction products in microtiter plates, and quantitation by enzyme-linked immunosorbent assay. Right ventricular biopsies from 16 patients after heart transplantation (left ventricular ejection fraction 67 +/- 7%) were compared with 12 patients with normal cardiac function (left ventricular ejection fraction 62 +/- 5%). A 46% lower AT1 mRNA content was found in biopsies from the 16 patients after heart transplantation than in the 12 controls (heart transplantation, 200 +/- 25 AT1 mRNA copies/ng RNA; controls, 368 +/- 50; P < 0.01). When AT1 mRNA content was related to the stably expressed GAPDH mRNA, a 49% decrease was detected (AT1/GAPDH: patients, 2.4 +/- 0.25; controls, 4.7 +/- 0.6; P < 0.006). No association between the extent of AT1 downregulation and clinical or hemodynamic variables was detected. In the human heart ventricular AT1 is downregulated after orthotopic heart transplantation. The decrease in AT1 mRNA is not associated with altered systolic function. This may partially reflect a loss of autonomic nerves and thus altered nervous control of the heart.
 ...
PMID:Decreased expression of ventricular angiotensin receptor type 1 mRNA after human heart transplantation. 897 19

Endothelin-converting enzyme-1 (ECE-1) plays a substantial role in activation of the endothelin (ET) system by cleaving the precursor, big ET-1, to the active peptide ET-1. The aim of this study was to investigate whether ECE-1 mRNA expression is modified in human cardiovascular disease. ECE-1 expression was related to echocardiographic data, drug treatment, age, sex, and NYHA heart failure classification. A quantitative PCR assay (qPCR) was established to measure ECE-1 mRNA in these samples. The ECE-1 measurements were normalized over a simultaneously performed GAPDH qPCR. The results indicate a higher ECE-1 expression level in atrial tissue samples of patients who have experienced a myocardial infarction compared with those who did not (ECE-1/GAPDH: 5.81 +/- 0.76 fg/ng; n = 21 vs. 3.20 +/- 0.51 fg/ng; n = 22; p = 0.007). The transverse diameter of the left atrium over 37 mm was associated with a lower ECE-1 expression (ECE-1/GAPDH: 3.11 +/- 0.69 fg/ng; n = 18 vs. 5.12 +/- 0.65 fg/ng; n = 25; p = 0.044). In assessing the drug treatment, decreased ECE-1 expression could be observed in patients who received a beta-blocker (ECE-1/GAPDH: 3.90 +/- 58 fg/ng; n = 31 vs. 5.81 +/- 0.76 fg/ng; n = 12; p = 0.077). These data suggest an involvement of the ET system is cardiovascular disease that may be clinically important.
 ...
PMID:Endothelin-converting enzyme-1 mRNA expression in human cardiovascular disease. 959 98

Creatine kinase (CK) plays a crucial role in cardiac energy transduction. During chronic cardiac stress conditions leading to hypertrophy and/or heart failure, the profile of CK isoenzyme activities changes towards a fetal pattern with increases of BB- and MB-CK and decreases of MM-CK and mito-CK. Changes of myocardial CK gene expression are only indirectly reflected by measurements of CK activities. The purpose of this work was, therefore, to determine myocardial expression of B-, M- and sarcomeric mito-CK genes in an animal model of heart failure where hemodynamic alterations and CK system changes are well defined, that is, in the rat heart post-myocardial infarction. Intact residual left ventricular myocardium was harvested 2 months following infarction (MI; n = 7) or sham operation (sham; n = 6) after in vivo left-ventricular end-diastolic pressure (LVEDP) was recorded. Total CK activity was measured spectrophotometrically, CK isoenzyme distribution with agarose gel electrophoresis. Steady state mRNA levels coding for B-, M- and mito-CK genes were measured with quantitative PCR and were normalized for GAPDH expression. Total CK activity tended to be reduced in MI (5.51 +/- 0.62 IU/mg protein) compared to sham (6.77 +/- 0.24; P = 0.55). CK isoenzyme distribution showed an increase of fetal BB- + MB-CK (MI 22.0 +/- 3.1%, sham 15.1 +/- 1.0%; P < 0.05), no change of MM-CK and a decrease of mito-CK (27.0 +/- 1.5% sham, 20.8 +/- 2.0% MI: P < 0.05). Relative B-CK mRNA levels increased (sham 0.46 +/- 0.06, MI 1.03 +/- 0.09; P < 0.05) and M-CK mRNA levels decreased (sham 1.06 +/- 0.08. MI 0.66 +/- 0.09; P < 0.05) significantly post-MI. The increase of B-CK mRNA (r = 0.72; P = 0.009) and the decrease of M-CK mRNA (r = 0.76; P = 0.003) correlated significantly with in vivo LVEDP. Mito-CK mRNA levels remained unchanged after MI (sham 0.94 +/- 0.16, MI 0.98 +/- 0.09). Intact residual left-ventricular myocardium post-MI is characterized by increased B-CK-mRNA and reduced M-CK-mRNA expression.
 ...
PMID:Changes of creatine kinase gene expression in rat heart post-myocardial infarction. 960 29

1. Adrenomedullin is a recently discovered vasodilating and natriuretic peptide whose physiological and pathophysiological roles remain to be established. Like atrial natiuretic peptide adrenomedullin is expressed in the left ventricle. Ventricular expression of atrial natriuretic peptide is known to be markedly increased by volume or pressure overload. In this study we investigated whether ventricular expression of adrenomedullin is similarly stimulated under such conditions. 2. Ventricular adrenomedullin and atrial natriuretic peptide mRNA levels as well as those of a loading control mRNA (glyceraldehyde-3-phosphate dehydrogenase) were quantified by Northern blot analysis in (a) rats with severe post-infarction heart failure induced by left coronary ligation at 30 days post-surgery and (b) in rats with pressure-related cardiac hypertrophy induced by aortic banding at several time points (0.5, 1 and 4 h, and 1, 4, 7 and 28 days) after surgery. Levels were compared with those in matched sham-operated controls. 3. The mRNA level of atrial natriuretic peptide was markedly increased (8-10-fold) in the left ventricle of animals with post-infarction heart failure. In contrast, there was only a modest (40%) increase in the level of adrenomedullin mRNA. In rats with pressure-induced cardiac hypertrophy the ventricular level of atrial natriuretic peptide mRNA was again markedly increased (maximum 10-fold). The increase was first noticeable at 24 h post-banding and persisted until 28 days. In contrast, there was no change in adrenomedullin mRNA level compared with sham-operated rats at any time point. 4. Despite having similar systemic effects, the expression of adrenomedullin and atrial natriuretic peptide in the left ventricle is differently regulated. The findings imply distinct roles for the two peptides. The results do not support an important role for ventricular adrenomedullin expression in the remodelling process that occurs during the development of cardiac hypertrophy but suggest that ventricular adrenomedullin participates in the local and/or systemic response to heart failure.
 ...
PMID:Differential regulation of ventricular adrenomedullin and atrial natriuretic peptide gene expression in pressure and volume overload in the rat. 964 Mar 41

Sarcoplasmic reticulum (SR) Ca2+-ATPase gene expression is reduced in the failing myocardium. However, the functional relevance of these changes to myocardial contractility is not yet established. We assessed myocardial contractile function by analyzing sarcomere motion of isolated myocytes and also quantified SR Ca2+ regulatory protein gene expression by Northern blot analysis in the same hearts obtained from 10 dogs with pacing-induced heart failure (HF; 240 beats/min, 4 wk) and 7 control dogs. Sarcomere-shortening velocity was depressed in HF myocytes, accompanied by the prolongation of intracellular Ca2+ concentration ([Ca2+]i) transient measured by indo 1 fluorescence ratio. SR Ca2+-ATPase mRNA levels (normalized to glyceraldehyde-3-phosphate dehydrogenase mRNA) were significantly depressed in HF, and calsequestrin mRNA was increased. For control and HF dogs, sarcomere-shortening velocity correlated positively with Ca2+-ATPase mRNA levels (r = 0.73, n = 17, P < 0.01) but not with calsequestrin mRNA. Ca2+-ATPase mRNA levels were correlated with 45Ca2+ uptake rate by SR, which was also reduced in HF. Moreover, the inhibition of SR Ca2+-ATPase with thapsigargin or cyclopiazonic acid reproduced in normal myocytes the abnormalities observed in HF myocytes, such as depressed contractility and the prolonged [Ca2+]i transient duration. A downregulation of Ca2+-ATPase gene expression and a resultant decrease in Ca2+ uptake by SR may be responsible for the contractile dysfunction and the alterations of [Ca2+]i transient in HF.
 ...
PMID:Role of SR Ca2+-ATPase in contractile dysfunction of myocytes in tachycardia-induced heart failure. 968 93


1 2 3 4 Next >>