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

The obese ZDFxSHHF-fa/fa(cp) model was developed by crossing lean female Zucker Diabetic Fatty (ZDF +/fa) and lean male Spontaneously Hypertensive Heart Failure (SHHF/Mcc-fa(cp), +/fa) rats. The purpose of the present study was to determine renal function and morphology, hemodynamics, and metabolic status in ZDFxSHHF rats. Two sets of experiments were conducted. First, we evaluated heart and kidney function and metabolic status in aged (46 weeks old) male obese ZDFxSHHF and age matched obese SHHF rats, lean Spontaneously Hypertensive (SHR) and lean normotensive Wistar Kyoto (WKY) rats. In the second set of experiments, renal function and structure as well as metabolic and lipid status were determined in lean (LN) and obese (OB) adult (29-weeks of age) ZDFxSHHF rats. At 46 weeks of age ZDFxSHHF rats are hypertensive expressing marked cardiac hypertrophy associated with diastolic dysfunction and preserved contractile function. Fasted hyperglycemia and hyperinsulinemia are accompanied by moderate hypercholesterolemia and hypertriglyceridemia. Obese aged ZDFxSHHF have marked renal hypertrophy, a 3-8 fold decrease in creatinine clearance (compared with SHHF, SHR and WKY), a high percent of segmental + global glomerulosclerosis (59.8%+/-10.8), and severe tubulointerstitial and vascular changes. Obese ZDFxSHHF rats die at an early age (approximately 12 months) from end-stage renal failure. Studies conducted in 29-week animals showed that, although both LN and OB 29-week old animals are hypertensive, OB animals have more severely compromised renal function and structure as compared with lean litter-mates (kidney weight: 2.56+/-0.16 vs. 1.61+/-0.12 g; creatinine clearance: 0.42+/-0.04 vs. 1.24+/-0.13 L/g kid/day; renal vascular resistance 12.39+/-1.4 vs. 6.14+/-0.42 mmHg/mL/min/g kid; protein excretion: 556+/-16 vs. 159+/-9mg/day/g kid, p < 0.05, OB vs. LN, respectively). Obesity is also associated with hyperglycemia (424+/-37 vs. 115+/-11 mg/dL), hyperinsulinemia (117.2+/-8.8 vs. 42.3+/-3.5 microU/mL), hypertriglyceridemia (5200+/-702 vs. 194+/-23 mg/dL), hypercholesterolemia (632+/-39 vs. 109+/-4mg/dL), and presence of segmental + global glomerulosclerosis (20.1+/-3.2% vs. 0.1+/-0.1%) with prominent tubular and interstitial changes (p < 0.05, OB vs. LN, respectively). In summary, the present study indicates that the crossing of rat strains of nephropathy produces hybrids that carry a high risk for severe renal dysfunction. The ZDFxSHHF rats express insulin resistance, hypertension, dislipidemia and obesity and develop severe renal dysfunction. In addition, the hybrids do not develop some of the complications (hydronephrosis or congestive heart failure) common for the parental strains that may compromise studies of renal function and structure. Therefore, the ZDFxSHHF rat may be a useful model fore valuating risk factors and pharmacological interventions in chronic renal failure.
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PMID:Renal function and structure in diabetic, hypertensive, obese ZDFxSHHF-hybrid rats. 1090 Nov 78

Measurement of regional sympathetic activity in lean essential hypertension patients using electrophysiologic (sympathetic nerve recording) and neurochemical (measurement of norepinephrine spillover) techniques demonstrates activation of sympathetic outflow to the heart, kidneys, and skeletal muscle vasculature in younger (< 45 years) patients. The increase in sympathetic activity is a mechanism for both initiating and sustaining the blood pressure elevation. Sympathetic nervous activation also confers specific cardiovascular risk. Stimulation of the sympathetic nerves to the heart promotes the development of left ventricular hypertrophy and contributes to the genesis of ventricular arrhythmias and sudden death. Sympathetically mediated vasoconstriction in skeletal muscle vascular beds reduces the uptake of glucose by muscle, and is thus a basis for insulin resistance and consequent hyperinsulinemia. Understanding the neural pathophysiology of obesity-related hypertension has been more difficult. In normotensive obesity, renal sympathetic tone is doubled, but cardiac norepinephrine spillover (a measure of sympathetic activity in the heart) is only 50% of normal. In obesity-related hypertension, there is a comparable elevation of renal norepinephrine spillover, but without suppression of cardiac sympathetics, as here cardiac norepinephrine spillover is more than double that of normotensive obese and 25% higher than in healthy volunteers. Increased renal sympathetic activity in obesity may be a necessary cause for the development of hypertension (predisposing to hypertension development), but apparently is not a sufficient cause. The discriminating feature of the obese who develop hypertension is the absence of the presumably adaptive suppression of cardiac sympathetic outflow seen in the normotensive obese. The sympathetic nervous system has moved towards center stage in cardiovascular medicine. The importance of sympathetic activation in heart failure progression and mortality and in the generation of ventricular arrhythmias is now well established. In essential hypertension also, although the mechanism differs somewhat between the lean and obese, the sympathetic nervous system is a key factor in the genesis of the disorder, and additionally promotes the development of complications. Through their central inhibition of sympathetic nervous activity, I1 agents such as rilmenidine powerfully reduce sympathetic nervous activity in essential hypertension patients, lowering blood pressure, and carrying the potential for specific cardiovascular protection.
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PMID:The sympathetic system and hypertension. 1092 28

The left ventricular hypertrophy is a risk marker of the cardiovascular morbidity and mortality in hypertensive patients--it contributes to sudden death, myocardial infarction, myocardial ischemia, heart failure, arrhythmias, left ventricular diastolic dysfunction, stroke and renal failure. The mechanisms by which the heart hypertrophy increases the risk of cardiovascular morbidity and mortality, however, is not completely clear yet. Pressure overload (resulting in the concentric hypertrophy) and volume overload (resulting in the eccentric hypertrophy) of the left ventricle play a significant role in the development of the hypertrophy of the left ventricle. Other risk factors, stimulating left ventricular hypertrophy, include growth factors, genetic predisposition, age, obesity, hyperinsulinemia and anemia. The hypertrophy of left ventricle most often occurs with hypertension, cardiomyopathy and aortic stenosis. Several clinical studies evaluated functional consequences of the reduction of the ventricular hypertrophy and found out that the function of the left ventricle to be improved in hypertensive patients who had undergone an effective and long-term antihypertensive treatment. However, these studies did not differentiate whether for the improvement in the function of left ventricle was the matter of the reduction of the left ventricular mass or whether it was because of the decrease of the arterial pressure during the period of anti-hypertensive treatment. On the basis of the literature studied we can emphasize that the reduction of myocardial hypertrophy resulting from a specific antihypertensive treatment appears to be more favourable than harmful for the heart's pump performance.
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PMID:[Hypertrophy of the left ventricle--etiopathogenesis, clinical consequences and prognosis]. 1104 62

Insulin resistance and hyperinsulinemia have been observed in over 70% of the nonobese, nondiabetic subjects with essential hypertension (HT). Alpha-1 blockers, ACE-antagonists, long-acting Ca blockers including nifedipine CR, some form of beta-blockers, tilisolor, which is reported to increase blood flow, improve insulin sensitivity when blood pressure is better controlled. Decrease of serum potassium during insulin sensitivity test and intraplatelet free Ca2+ concentration is positively and negatively correlated with insulin sensitivity, respectively. Blood pressure is correlated with insulin resistance, which is also observed in secondary HT. The resistance is correlated with salt sensitivity as well as impaired nocturnal fall of blood pressure. These suggest the possible association of insulin resistance with altered intracellular cation metabolism. Insulin resistance and associated hyperinsulinemia have been observed in effort as well as vasospastic angina pectoris (VSAP), atherothrombotic cerebral infarction, and in ASO without obesity, HT, or diabetes, suggesting the resistance resulting from endothelial dysfunction. Insulin resistance has been observed in heart failure and is correlated with angiotensin II. Resistance is also observed in hypertrophic cardiomyopathy and is partially correlated with TNF-alpha. These results indicate that insulin resistance seem to be multifactorial. An effort to normalize insulin sensitivity is crucial to eliminate multiple risk factors as well as to prevent the progression of atherosclerotic vascular lesions.
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PMID:Multifactorial insulin resistance and clinical impact in hypertension and cardiovascular diseases. 1187 61

There are almost one hundred inborn errors of metabolism which can start in the neonatal period, but less than 20 are amenable to treatment. In general, an extremely evocative clinical setting is the course of a full-term baby born after normal pregnancy and delivery who, after an initial symptom-free period deteriorates relentlessly for no apparent reason and does not respond to symptomatic therapy. Investigations routinely performed in all sick neonates yield normal results. Emergency treatment must be undertaken in parallel with investigations. Five main presentations can be observed: a neurologic deterioration 'intoxication' type mostly suggests maple syrup urine disease, methylmalonic, propionic, isovaleric acidaemias and urea cycle disorders. Isolated seizures is the revealing symptom of pyridoxine-responsive and folinic acid responsive seizures. A jaundice or a liver failure suggest galactosaemia, fructosaemia, tyrosinaemia type I (after 3 weeks), phosphomannoisomerase deficiency or bile acid synthesis defects. Cardiac failure and heartbeat disorders should first suggest mitochondrial fatty acid oxidation (FAO) disorders. Persistent hypoglycaemia is the presenting sign of glyco/gluconeogeneis defects, hyperinsulinism and FAO disorders. The first line investigation relies upon the collection at the same time of a few samples including blood gases electrolytes, prothrombin time, transaminases, ammonia and lactic acid, and the search for ketonuria. The storage of plasma, urine and blood (on filter paper) is an important element in the diagnosis. The utilization of these samples should be carefully planned after taking advice from specialists in inborn errors.
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PMID:Clinical approach to inherited metabolic disorders in neonates: an overview. 1206 34

During the neonatal period, inborn errors of metabolism mostly present with an overwhelming illness that requires prompt diagnosis and both supportive and specific treatments. The most frequent situations are due to branched-chain organic acidurias that present with ketoacidosis and urea cycle defects that are characterized by hyperammonaemia. During both situations, toxin removal procedures and nutritional support with a free-protein and high-energy diet are pivotal treatments. In patients presenting with hypoglycaemia blood glucose levels must be corrected. Progress following glucose provision is useful in recognizing the disorders that are mainly implicated. Hyperinsulinism requires high-glucose infusion. Glycogen storage diseases and gluconeogenesis defects are easily treated with a permanent glucose provision while hypoglycaemias quickly recur. In patients with galactosaemia, hereditary fructose intolerance or tyrosinaemia type I, the presentation is dominated by a liver failure requiring galactose and fructose exclusion associated with a low-protein diet. Many patients with beta-oxidation defects may present with hypoglycaemia that is usually easily corrected. The precise diagnosis can be easily missed in those patients that do well in the following weeks but may develop cardiac failure, arrhythmia and/or liver failure. Patients presenting with intractable convulsions, vitamin responsiveness to biotin, pyridoxine and folate must be considered.
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PMID:Management and emergency treatments of neonates with a suspicion of inborn errors of metabolism. 1206 35

Endothelins are powerful vasoconstrictor agents produced by endothelial cells and identified by Yanagisawa et al. in 1988. Two types of receptors for endothelins have been identified: ET(A) receptors are located on smooth muscle cells of the vascular wall and are responsible for endothelin-induced vasoconstriction while ET(B) receptors are located on endothelial cells and induce these cells to release NO and prostacyclin. Moreover, these peptides not only cause a potent and prolonged vasoconstriction but are also known to enhance cell proliferation and to stimulate extracellular matrix accumulation. High levels of plasma or tissue endothelins have been found in patients with heart failure, diabetes, stroke, primary pulmonary hypertension, liver cirrhosis and other diseases. Given these effects of endothelins, blocking their receptors might be a new way to reduce blood pressure and to treat other illnesses. Accordingly, many endothelin antagonists have been developed and evaluated in animals and humans. Enrasentan is a mixed ET(A) and ET(B) receptor antagonist with a higher affinity for ET(A) receptors, although it cannot be considered a selective antagonist. In an animal model of hypertension and cardiac hypertrophy the drug has reduced blood pressure, prevented cardiac hypertrophy and preserved myocardial function. In rats with hyperinsulinemia and hypertension enrasentan normalized blood pressure and prevented cardiac and renal damage. In rats with stroke the drug reduced the ischemic area in the brain. Enrasentan has been added to conventional treatment in patients with heart failure (NYHA Class 2-3) and no addictive effect of the drug has been observed. This is in contrast with results obtained in animal models and still has not been explained. In conclusion, many possible clinical applications can be suggested for this drug, but further studies are necessary to better evaluate its therapeutic efficacy.
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PMID:Enrasentan, an antagonist of endothelin receptors. 1259 14

Heart failure is known to be a complication of insulin-dependent (IDDM) and noninsulin-dependent diabetes mellitus (NIDDM) even in the absence of coronary heart disease or hypertension. The mechanisms leading to diabetic cardiomyopathy are unknown. The aim of the study was to characterize structural and functional alterations in hyperinsulinemic Zucker diabetic fatty (ZDF) rats treated with or without insulin. Diabetic animals showed a twofold increase in cardiomyocyte volume with increased left ventricular ANP but not BNP mRNA levels in spite of a reduced plasma renin activity (PRA) 2 months after onset of diabetes compared to nondiabetic littermates. These changes were associated with an increase in left ventricular performance as assessed by echocardiography. Insulin treatment led to a significant increase in body weight (BW), total heart weight, myocardial protein content, and left ventricular mass (LVM). Perivascular fibrosis and laminin thickness were significantly augmented in diabetic rat myocardium irrespective of insulin treatment, whereas interstitial collagen I and fibronectin were similarly found in diabetic and control myocardium. Initial stages of diabetic cardiomyopathy in hyperinsulinemic rats are characterized by cardiomyocyte hypertrophy and enhanced cardiac contractility. It is suggested that hyperinsulinemia may be involved in cardiac hypertrophy.
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PMID:Myocardial hypertrophy and enhanced left ventricular contractility in Zucker diabetic fatty rats. 1476 80

Abnormalities in energy metabolism may play an important role in the development of hypertensive heart failure. However, the transition from compensated hypertrophy to heart failure is not fully understood in terms of energy metabolism. In Dahl salt-sensitive (DS) and salt-resistant (DR) rats, myocardial fatty acid and glucose uptake values were determined using (131)I- or (125)I-labeled 9-methylpentadecanoic acid ((131)I- or (125)I-9MPA), and [(14)C]deoxyglucose ([(14)C]DG), fatty acid beta-oxidation was identified using thin-layer chromatography, and insulin-stimulated glucose-uptake was observed using a euglycemic hyperinsulinemic glucose clamp. Six-week-old rats were fed a diet that contained 8% NaCl, which resulted in development of compensated hypertrophy in DS rats at 12 wk of age and ultimately led to heart failure by 18 wk of age. Uptake of [(14)C]DG increased markedly with age in the DS rats, whereas (131)I-9MPA uptake was marginally but significantly increased only in animals aged 12 wk. The ratio of (125)I-9MPA beta-oxidation metabolites to total uptake in the DS rats was significantly lower (P < 0.05) at 12 (37%) and 18 (34%) wk compared with at 6 (45%) wk. Insulin increased [(14)C]DG uptake more than twofold in the DS rats at 6 wk, although this increase was markedly attenuated at 12 and 18 wk (11 and 8%, respectively). Our data suggest that in a hypertrophied heart before heart failure, fatty acid oxidation is impaired and the capacity to increase glucose uptake during insulin stimulation is markedly reduced. These changes in both glucose and fatty acid metabolism that occur in association with myocardial hypertrophy may have a pathogenic role in the subsequent development of heart failure.
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PMID:Saturated glucose uptake capacity and impaired fatty acid oxidation in hypertensive hearts before development of heart failure. 1503 Nov 23

Glucocorticoids impair insulin sensitivity. Because insulin resistance is closely linked to increased incidence of cardiovascular diseases and given that metabolic abnormalities have been linked to initiation of heart failure, we examined the acute effects of dexamethasone (DEX) on rat cardiac metabolism. Although injection of DEX for 4 h was not associated with hyperinsulinemia, the euglycemic-hyperinsulinemic clamp showed a decrease in glucose infusion rate. Rates of cardiac glycolysis were unaffected, whereas the rate of glucose oxidation following DEX was significantly decreased and could be associated with augmented expression of PDK4 mRNA and protein. Myocardial glycogen content in DEX hearts increased compared with control. Similar to hypoinsulinemia induced by streptozotocin (STZ), hearts from insulin-resistant DEX animals also demonstrated enlargement of the coronary lipoprotein lipase (LPL) pool. However, unlike STZ, DEX hearts showed greater basal release of LPL and were able to maintain their high heparin-releasable LPL in vitro. This effect could be explained by the enhanced LPL mRNA expression following DEX. Our data provide evidence that in a setting of insulin resistance, an increase in LPL could facilitate increased delivery of fatty acid to the heart, leading to excessive triglyceride storage. It has not been determined whether these acute effects of DEX on cardiac metabolism can be translated into increased cardiovascular risk.
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PMID:Single-dose dexamethasone induces whole-body insulin resistance and alters both cardiac fatty acid and carbohydrate metabolism. 1522 Feb 3


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