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Query: UMLS:C0018801 (heart failure)
 72,216 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Lipid peroxidation (LPO) was studied in 90 patients with chronic heart failure (CHF) in relation to the disease stage. The patients with various CHF showed increased LPO and decreased antioxidative function. Impaired LPO was more pronounced in patients with Stage II CHF. To correct LPO processes, emoxipine, a new synthetic antioxidant, was used in 48 patients. The agent in a dose of 40 mg/day was ascertained to have a regulatory effect on the oxidative-antioxidative system in patients with heart failure. A more profound effect was observed in patients with Stage I patients. The main mechanism of the antioxidative action of emoxipine in CHF was to enhance glutathione reductase and glutathione peroxidase and to lower the level on dienic conjugates in patients with Stage IIB CHF.
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PMID:[Effects of emoxipine on lipid peroxidation in patients with chronic heart failure]. 180 67

Changes in myocardial function, structure, high energy phosphates and lipid peroxide content were examined in hypertrophied hearts exposed to partially reduced forms of oxygen (PRFO) in an ex vivo system. Heart hypertrophy in rats was produced by narrowing of the abdominal aorta for 6, 12, 24, and 48 weeks. During this period, a stable hypertrophy and hyperfunction with no clinical signs of heart failure is reported to be accompanied by an increase in myocardial superoxide dismutase and glutathione peroxidase activities and a decrease in lipid peroxide content (Gupta and Singal, Circ. Res. 64:398-406, 1989). A 10-min perfusion of sham control hearts with PRFO caused a significant decline in the developed force, +/- dF/dt and a rise in resting tension. These changes due to PRFO were significantly less in all groups of hypertrophied hearts. PRFO produced 80.8 +/- 4.2% increase in malondialdehyde (MDA) content in sham controls, while different groups of hypertrophied hearts showed significantly lesser increase (range 45-50%) in MDA. PRFO resulted in loss of myocardial ATP and CP in control and hypertrophied groups, but this loss was significantly less in all groups of hypertrophied hearts. Both quantitative and qualitative ultrastructural changes due to PRFO were also found to be less in hypertrophied hearts. There were no significant differences among 6- to 48-week hypertrophy groups in their response to PRFO. The study suggests that endogenous antioxidants may serve as putative stabilizers of myocardial subcellular as well as contractile functions against oxidative stress.
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PMID:Reduced myocardial injury due to exogenous oxidants in pressure induced heart hypertrophy. 183 11

Antioxidant enzyme activities, including superoxide dismutase, glutathione peroxidase and catalase, are known to be altered under various physiological and pathophysiological conditions. There is a significant increase in some of these activities in the myocardium during stable hyperfunctional heart hypertrophy subsequent to pressure overload, as well as after exercise training in rats. Hearts with increased antioxidant capacity have been reported to be more resistant to in vivo and in vitro oxidative stress. On the other hand, cardiomyopathy and heart failure under a variety of conditions are accompanied by increased free radicals and lipid peroxidation. These data lead to the hypothesis that maintained or improved function during compensated heart hypertrophy may be supported by an increased antioxidant capacity, and a relative deficit in this 'antioxidant reserve' may contribute in the decompensated state.
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PMID:A relative deficit in antioxidant reserve may contribute in cardiac failure. 213 50

Primary (dienic conjugates) and secondary (malonic dialdehyde) products of plasma lipid peroxidation were measured and the activity of antioxidative enzymes (glutathione peroxidase and superoxide dismutase) in erythrocytes was determined in 96 patients with chronic heart failure due to ischemic heart disease and rheumatic heart disease. Heart failure was found to show elevated plasma lipid peroxidation product levels, mostly in Stages I and IIA. Whereas in Stage IIB, the product levels became lower and in Stage III, they reached the control values. Similarly, the activity of superoxide dismutase varied with the stages of heart failure. That of glutathione peroxidase increased with circulatory decompensation development, reaching the maximal level in Stage IIB, then decreased down to the values observed in the control groups of patients without heart failure. The changes detected were not related to the causes of heart failure.
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PMID:[Changes in antioxidative enzyme activity in patients with chronic heart failure]. 238 Nov 25

Changes in oxygen radical mechanisms during 6-48 weeks of heart hypertrophy in rats subjected to a narrowing of the subdiaphragmatic aorta were examined. During this period, hypertrophied hearts demonstrated a stable hyperfunction, as indicated by an elevated but stable left ventricular systolic pressure, dP/dt, and aortic pressure and no change in left ventricular end diastolic pressure. Experimental animals showed increased heart-to-body weight ratios; however, the conventional signs of heart failure such as increased wet-to-dry weight ratios of liver and lung, ascites, or pleural effusion were absent. Hearts were examined for superoxide dismutase, glutathione peroxidase, and lipid peroxide activities. The superoxide dismutase activity was significantly higher in hypertrophied hearts at 6 and 12 weeks as compared with sham-operated rats (sham controls), while no difference was seen at 24 and 48 weeks due to a marked increase in the superoxide dismutase activity of sham control hearts in these age groups. During the period studied, glutathione peroxidase activity remained unchanged in controls but was significantly elevated in hypertrophied hearts. Lipid peroxide activity as indicated by the malondialdehyde content was significantly lower in hypertrophied hearts. Perfusion of isolated control and hypertrophy hearts with xanthine-xanthine oxidase, an exogenous source of oxygen radicals, resulted in contractile failure and rise in resting tension. In hypertrophied hearts, however, the contractile force was better maintained and there was a lesser rise in resting tension after exposure to xanthine-xanthine oxidase. The study suggests the development of a higher antioxidative capacity during the stable phase of hypertrophy due to a chronic pressure overload.
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PMID:Higher antioxidative capacity during a chronic stable heart hypertrophy. 252 64

We hypothesize that oxygen free radicals are involved in the genesis and maintenance of volume and pressure overload heart failure. Pressure and volume overload would produce myocardial ischemia. During ischemia there will be an increase in xanthine and xanthine oxidase; and a decrease in the superoxide dismutase and glutathione peroxidase activity leading to an increase in the oxygen free radicals. A decrease in the cellular pH during ischemia would release phospholipase which would, in turn, release arachidonic acid from phospholipids. Leukotrienes and prostaglandins will be synthesized through arachidonic acid metabolism. During this synthesis not only oxygen free radicals will be produced but also there will be formation of leukotriene, LTB4, which is known to activate neutrophil and hence increased secretion of oxygen free radicals. Increased circulatory catecholamines due to compensatory mechanism would also lead to an increase in the oxygen free radicals. Oxygen free radicals are known to depress Ca++ binding and uptake of sarcoplasmic reticulum which would lead to a decrease in the myocardial contractility. We have shown that oxygen free radicals depress cardiac function and cardiac contractility. It is, therefore, suggested that oxygen free radicals might be involved in the development of heart failure. The use of agents that reduce the amount of oxygen free radicals would be of value in the prevention and treatment of heart failure.
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PMID:Oxygen free radicals and heart failure. 283 9

The present study has examined early cellular effects of chronic adriamycin administration to dogs using a protocol (1 mg/kg/week to a total cumulative dose of 240 mg/m2) producing significant but small reductions in ejection fraction and stroke volume as determined echocardiographically prior to the development of clinical or radiological manifestations of heart failure. At this early phase of cardiomyopathy, significant reduction (P less than 0.05) in sarcoplasmic reticulum Ca2+, K+-ATPase was observed without any change in mitochondrial, lysosomal or sarcolemmal marker enzymes. Myocardial calcium (P less than 0.01) and glutathione (P less than 0.001) levels were increased significantly. Detailed analysis of myocardial phospholipid profiles failed to show any significant differences between control and treated dogs. In contrast, red cell membranes showed increased phosphatidylcholine (PC) and decreased phosphatidylserine (PS) contents, resulting in a significant increase in PC/PS ratio (P less than 0.05). No significant changes were detected in activities of catalase, superoxide dismutase or glutathione peroxidase in erythrocytes or myocardial tissue from control and adriamycin-treated animals. A significant (P less than 0.05) elevation in plasma sialic acid was observed following adriamycin treatment. Our results suggest that early adriamycin-induced damage is unlikely to result from alterations in cellular processes protecting tissues against oxidant injury. Regression analysis indicated that, of the various abnormalities observed, only the elevated myocardial calcium levels and the increases in plasma sialic acid correlated with the degree of myocardial functional impairment. Our findings suggest the presence of sarcolemmal alterations in Ca2+ handling in early adriamycin-induced myocardial injury and indicate that measurement of plasma sialic acid should be further investigated as a possible noninvasive indicator of impending adriamycin cardiotoxicity.
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PMID:Adriamycin cardiomyopathy: implications of cellular changes in a canine model with mild impairment of left ventricular function. 299 97

It is found that glutathione reductase and superoxidismutase activity decreases in postmitochondrial fraction of the myocardium tissue under cardiovascular insufficiency of the hemodynamic type. In erythrocytes the activity of lipoperoxide-detoxicating glutathione peroxidase--GSH-peroxidase II lowers and that of hydrogen peroxide-utilizing GSH-peroxidase I grows. Disturbances in the antioxidant enzymic systems are discussed for their role in development of cardiac insufficiency.
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PMID:[Activity of enzymes with an antioxidant action in the myocardium and blood of the rat during cardiovascular insufficiency]. 671 Jun 16

During radiotherapy of thoracic tumors, the heart is often included in the primary treatment volume, and chronic impairment of myocardial function occurs. The cellular biomolecules are altered directly by radiation or damaged indirectly by free radical production. The purpose of this investigation was to evaluate the biochemical and functional responses of the rat heart to a single high dose of radiation. The effect of 20 Gy local X irradiation was determined in the heart of Wistar rats under general anesthesia. Mechanical performances were measured in vitro using an isolated perfused working heart model, and cardiac antioxidant defenses were also evaluated. Hearts were studied at 1 and 4 months after irradiation. This single dose of radiation induced a marked drop in the mechanical activity of the rat heart: aortic output was significantly reduced (18% less than control values) at 1 month postirradiation and remained depressed for the rest of the experimental period (21% less than control 4 months after treatment). This suggests the development of myocardial failure after irradiation. The decline of functional parameters was associated with changes in antioxidant defenses. The decrease in cardiac levels of vitamin E (-30%) was associated with an increase in the levels of Mn-SOD and glutathione peroxidase (+45.5% and +32%, respectively, at 4 months postirradiation). However, cardiac vitamin C and catalase levels remained constant. Since these antioxidant defenses were activated relatively long after irradiation, it is suggested that this was probably due to the production of free radical species associated with the development of inflammation.
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PMID:Effect of in vivo heart irradiation on the development of antioxidant defenses and cardiac functions in the rat. 756 73

Hypertrophy and heart failure were induced by placing a mildly constrictive band around the ascending aorta in young guinea pigs. Based on heart weight, left ventricular wall thickness, hemodynamic data, and other clinical signs, these animals were found to have physiological hypertrophy at 10 wk and congestive heart failure (CHF) at 20 wk. Hearts from these two groups of animals were examined for superoxide dismutase (SOD), glutathione peroxidase (GSHPx), and catalase activities as well as lipid peroxidation and glutathione [reduced glutathione (GSH)/oxidized glutathione (GSSG)] levels. There was an age-dependent increase in SOD activity and GSH content in sham controls. SOD activity was 28% higher in the 10-wk-hypertrophy group and 46% lower in the CHF group than in respective sham controls. GSHPx activity increased significantly in the hypertrophied hearts, whereas in the failing hearts, the activity was not different from the 20-wk controls but was significantly lower than in the hypertrophied hearts. Catalase activity did not change at either stage. GSH content in the hypertrophied hearts was significantly higher compared with sham controls. In the CHF group, GSH content was significantly lower and GSSG content was significantly higher than in sham controls. Lipid peroxidation, as indicated by malondialdehyde content, was significantly decreased in the hypertrophy group but increased toward control levels in the failure group. It is proposed that a relative deficit in myocardial antioxidant capacity as well as in the redox state may play a role in the pathogenesis of cardiac failure.
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PMID:Antioxidant changes in hypertrophied and failing guinea pig hearts. 818 5


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