3-nitrotyrosine and Heart-Failure

Endothelial dysfunction associated with decreased nitric oxide (NO) bioactivity is a major feature of vascular diseases such as atherosclerosis or diabetes. Sodium nitroprusside (SNP)-induced relaxation is entirely dependent on cyclic guanosine monophosphate (cGMP) and preserved in atherosclerosis, suggesting that smooth muscle response to NO donor is intact. However, NO gas activates both cGMP-dependent and -independent signal pathways in vascular smooth muscle cells, and oxidative stress associated with vascular diseases selectively impairs cGMP-independent relaxation to NO. Sarco/endoplasmic reticulum Ca(2+) ATPase (SERCA), which regulates intracellular Ca(2+) levels by pumping Ca(2+) into store, is a major cGMP-independent target for NO. Physiological levels of reactive nitrogen species (RNS) S-glutathiolate SERCA at Cys674 to increase its activity, and the augmentation of RNS in vascular diseases irreversibly oxidizes Cys674 or nitrates tyrosine residues at Tyr296-Tyr297, which are associated with loss of function. S-glutathiolation of various proteins by NO can explain redox-sensitive cGMP-independent actions, and oxidative inactivation of target proteins for NO can be associated with the pathogenesis of cardiovascular diseases. Oxidative inactivation of SERCA is also implicated with dysregulation of smooth muscle migration, promotion of platelet aggregation, and impairment of cardiac function, which can be implicated with restenosis, pathological angiogenesis, thrombosis, as well as heart failure. Analysis of posttranslational oxidative modifications of SERCA and the preservation of SERCA function can be novel strategies against cardiovascular diseases associated with oxidative stress.

Topics: Animals; Antioxidants; Atherosclerosis; Cyclic GMP; Cyclic GMP-Dependent Protein Kinases; Diabetic Angiopathies; Endothelium, Vascular; Glutathione; Heart Failure; Humans; Mice; Models, Animal; Muscle, Smooth, Vascular; Nitric Oxide; Oxidative Stress; Protein Processing, Post-Translational; Rabbits; Rats; Sarcoplasmic Reticulum Calcium-Transporting ATPases; Tyrosine; Vasodilation

Oxidative stress is associated with maladaptive cardiac remodeling and vascular dysfunction and may be an important contributor to chronic heart failure (CHF) deterioration. We sought to investigate if the calcium sensitizer levosimendan beneficially modulates circulating markers of oxidative and nitrosative stress thus lessening their deleterious effects in patients with advanced CHF.. Thirty-nine patients with advanced CHF (mean NYHA 3.5+/-0.4; ischemic/dilated: 23/16; mean left ventricular ejection fraction: 26+/-7%) who were hospitalized due to syndrome worsening, were randomized (2:1) to receive either a 24-h levosimendan infusion of 0.1 microg/(kg min) (n=26) or placebo (n=13). Plasma b-type natriuretic peptide (BNP), circulating markers of oxidative [protein carbonyls, malondialdehyde (MDA)] and nitrosative (nitrotyrosine) stress, and cyclic GMP (cGMP) were measured at baseline and 48 h after each treatment.. Baseline characteristics and medications were well balanced in the two treatment groups. A significant improvement in left ventricular ejection fraction (P<0.01), NYHA class (P<0.01), and plasma BNP (P<0.01) was observed post-treatment only in the levosimendan group. Markers such as MDA, protein carbonyls and nitrotyrosine remained stable in the levosimendan-treated group, but significantly increased (P<0.05) in the placebo-treated patients. Neither therapeutic intervention changed the levels of circulating cGMP.. Levosimendan does not increase markers of oxidative and nitrosative stress in contrast to the placebo treatment, thus, exerting cardioprotective effects in advanced CHF patients. Moreover, levosimendan may exert its biologic action through non-cGMP-dependent biochemical pathways.

Topics: Aged; Anti-Arrhythmia Agents; Female; Heart Failure; Humans; Hydrazones; Male; Malondialdehyde; Middle Aged; Nitric Oxide; Oxidative Stress; Protein Carbonylation; Pyridazines; Simendan; Stroke Volume; Tyrosine

In the present study, we evaluated circulating pro-inflammatory mediators and markers of oxidative stress in patients with decompensated CHF (congestive heart failure) and assessed whether clinical recompensation by short-term inotropic therapy influences these parameters. Patients with worsening CHF (n=29, aged 61.9+/-2.7 years), NYHA (New York Heart Association) class III-IV, and left ventricular ejection fraction of 23.7+/-1.8% were studied. Controls comprised age-matched healthy volunteers (n=15; 54.1+/-3.2 years). Plasma levels of cytokines [IL (interleukin)-6 and IL-18], chemokines [MCP-1 (monocyte chemotactic protein-1)], adhesion molecules [sICAM (soluble intercellular adhesion molecule), sE-selectin (soluble E-selectin)], systemic markers of oxidation [TBARS (thiobarbituric acid-reactive substances), 8-isoprostaglandin F(2alpha) and nitrotyrosine] and hs-CRP (high-sensitivity C-reactive protein) were measured by ELISA and colorimetric assays at admission and 30 days following 72-h milrinone (n=15) or dobutamine (n=14) infusion. Plasma IL-6, IL-18, sICAM, E-selectin, hs-CRP and oxidative markers were significantly higher in patients on admission before inotropic treatment compared with controls (P<0.05). Short-term inotropic support improved clinical status as assessed by NYHA classification and by the 6-min walk test and significantly decreased plasma levels of IL-6, IL-18, sICAM, hs-CRP and markers of oxidation (P<0.05) at 30 days. The effects of milrinone and dobutamine were similar. In conclusion, our results demonstrate that patients with decompensated CHF have marked systemic inflammation and increased production of oxygen free radicals. Short-term inotropic support improves functional status and reduces indices of inflammation and oxidative stress in patients with decompensated CHF.

Topics: Biomarkers; C-Reactive Protein; Cardiotonic Agents; Case-Control Studies; Cell Adhesion Molecules; Chemokine CCL2; Colorimetry; Cytokines; Dinoprost; Disease Progression; Dobutamine; E-Selectin; Enzyme-Linked Immunosorbent Assay; Exercise Test; Female; Heart Failure; Humans; Inflammation; Interleukin-18; Interleukin-6; Male; Middle Aged; Milrinone; Oxidative Stress; Thiobarbituric Acid Reactive Substances; Tyrosine

Chronic heart failure (CHF) is accompanied by an inflammatory activation which occurs both systemically and in the skeletal muscle. Exercise training has been shown to reduce the local expression of cytokines and inducible nitric oxide synthase (iNOS) in muscle biopsies of CHF patients. INOS-derived NO can inhibit oxidative phosphorylation and contribute to skeletal muscle dysfunction in CHF.. To investigate the correlation between changes in local iNOS expression associated with regular exercise and changes in aerobic enzyme activities in the skeletal muscle of patients with CHF. Twenty male CHF patients [ejection fraction 25% (SE 2), age 54 (SE 2) years] were randomized to a training (n=10) or a control group (C, n=10).. At baseline and after 6 months skeletal muscle iNOS expression was measured by real-time polymerase chain reaction. INOS protein and protein nitrosylation were assessed by immunohistochemistry. Cytochrome c oxidase (COX) activity was quantified electrochemically using the Clark oxygen electrode.. Exercise training led to a 27% increase in cytochrome c oxidase activity [from 21.8 (SE 3.2) to 27.7 (SE 3.5) nmol O2/mg per min, P=0.02 versus baseline]. Changes in iNOS expression and iNOS protein content were inversely correlated with changes in COX-activity (r=-0.60, P=0.01; r=-0.71, P<0.001).. The inverse correlation between iNOS expression/iNOS protein content and COX-activity indicates that local anti-inflammatory effects may contribute to improved muscular oxidative metabolism.

Topics: Aged; Chronic Disease; Electron Transport Complex IV; Energy Metabolism; Exercise; Exercise Test; Exercise Tolerance; Follow-Up Studies; Heart Failure; Humans; Immunohistochemistry; Male; Middle Aged; Muscle, Skeletal; Nitric Oxide Synthase Type II; Oxidative Stress; Oxygen Consumption; Prospective Studies; Tyrosine

Chronic heart failure is characterized by decreased exercise capacity with early exacerbation of fatigue and dyspnea. Intrinsic skeletal muscle abnormalities can play a role in exercise intolerance. Causal or contributing factors responsible for muscle alterations have not been completely defined. This study evaluated skeletal muscle oxidative stress and NADPH oxidase activity in rats with myocardial infarction (MI) induced heart failure.. Four months after MI, rats were assigned to Sham, MI-C (without treatment), and MI-NAC (treated with N-acetylcysteine) groups. Two months later, echocardiogram showed left ventricular dysfunction in MI-C; NAC attenuated diastolic dysfunction. In soleus muscle, glutathione peroxidase and superoxide dismutase activity was decreased in MI-C and unchanged by NAC. 3-nitrotyrosine was similar in MI-C and Sham, and lower in MI-NAC than MI-C. Total reactive oxygen species (ROS) production was assessed by HPLC analysis of dihydroethidium (DHE) oxidation fluorescent products. The 2-hydroxyethidium (EOH)/DHE ratio did not differ between Sham and MI-C and was higher in MI-NAC. The ethidium/DHE ratio was higher in MI-C than Sham and unchanged by NAC. NADPH oxidase activity was similar in Sham and MI-C and lower in MI-NAC. Gene expression of p47(phox) was lower in MI-C than Sham. NAC decreased NOX4 and p22(phox) expression.. We corroborate the case that oxidative stress is increased in skeletal muscle of heart failure rats and show for the first time that oxidative stress is not related to increased NADPH oxidase activity.

Topics: Acetylcysteine; Animals; Ethidium; Free Radical Scavengers; Glutathione Peroxidase; Heart Failure; Heart Ventricles; Male; Malondialdehyde; Muscle, Skeletal; Myocardial Infarction; NADPH Oxidase 4; NADPH Oxidases; Oxidative Stress; Rats; Rats, Wistar; Reactive Oxygen Species; Superoxide Dismutase; Tyrosine

Exposure to fine particulate air pollution (PM₂.₅) is strongly associated with cardiovascular morbidity and mortality. Exposure to PM₂.₅ during pregnancy promotes reduced birthweight, and the associated adverse intrauterine conditions may also promote adult risk of cardiovascular disease. Here, we investigated the potential for in utero exposure to diesel exhaust (DE) air pollution, a major source of urban PM₂.₅, to promote adverse intrauterine conditions and influence adult susceptibility to disease. We exposed pregnant female C57Bl/6J mice to DE (≈300 µg/m³ PM₂.₅, 6 hrs/day, 5 days/week) from embryonic day (E) 0.5 to 17.5. At E17.5 embryos were collected for gravimetric analysis and assessed for evidence of resorption. Placental tissues underwent pathological examination to assess the extent of injury, inflammatory cell infiltration, and oxidative stress. In addition, some dams that were exposed to DE were allowed to give birth to pups and raise offspring in filtered air (FA) conditions. At 10-weeks of age, body weight and blood pressure were measured. At 12-weeks of age, cardiac function was assessed by echocardiography. Susceptibility to pressure overload-induced heart failure was then determined after transverse aortic constriction surgery. We found that in utero exposure to DE increases embryo resorption, and promotes placental hemorrhage, focal necrosis, compaction of labyrinth vascular spaces, inflammatory cell infiltration and oxidative stress. In addition, we observed that in utero DE exposure increased body weight, but counterintuitively reduced blood pressure without any changes in baseline cardiac function in adult male mice. Importantly, we observed these mice to have increased susceptibility to pressure-overload induced heart failure, suggesting this in utero exposure to DE 'reprograms' the heart to a heightened susceptibility to failure. These observations provide important data to suggest that developmental exposure to air pollution may strongly influence adult susceptibility to cardiovascular disease.

Topics: Air Pollutants; Animals; Aorta; Blood Pressure; Echocardiography; Female; Heart Failure; Inflammation; Inhalation Exposure; Leukocyte Common Antigens; Male; Maternal Exposure; Mice; Mice, Inbred C57BL; Myocardium; Necrosis; Oxidative Stress; Particle Size; Pregnancy; Pregnancy, Animal; Time Factors; Tyrosine; Vehicle Emissions; Weight Gain

Heart failure and related cardiac complications remains a great health challenge. We investigated the effects of upregulating heme-oxygenase (HO) on myocardial histo-pathological lesions, proinflammatory cytokines/chemokines, oxidative mediators and important markers of heart failure such as osteopontin and osteoprotergerin in N(ω)-nitro-l-arginine methyl ester (L-NAME)-induced hypertension. Treatment with the HO-inducer, heme-arginate improved myocardial morphology in L-NAME hypertensive rats by attenuating subendocardial injury, interstitial fibrosis, mononuclear-cell infiltration and cardiomyocyte hypertrophy. These were associated with the reduction of several inflammatory/oxidative mediators including chemokines/cytokines such as macrophage inflammatory protein-1 alpha (MIP-1α), macrophage chemoattractant protein-1 (MCP-1), tumor necrosis factor alpha (TNF-α), interleukin (IL)-6, IL-1β, endothelin-1, 8-isoprostane, nitrotyrosine, and aldosterone. Similarly, heme-arginate abated the elevated levels of extracellular matrix/remodeling proteins including transforming-growth factor beta (TGF-β1) and collagen-IV in the myocardium. These were accompanied by significant reduction of proteins of heart failure such as osteopontin and osteoprotegerin. Interestingly, the cardio-protective effects of heme-arginate were associated with the potentiation of adiponectin, atrial-natriuretic peptide (ANP), HO-1, HO-activity, cyclic gnanosine monophosphate (cGMP) and the total-anti-oxidant capacity, whereas the HO-inhibitor, chromium-mesoporphyrin nullified the effects of heme-arginate, exacerbating inflammatory injury and oxidative insults. We conclude that heme-arginate therapy protects myocardial damage by potentiating the HO-adiponectin-ANP axis, which in turn suppressed the elevated levels of aldosterone, pro-inflammatory chemokines/cytokines, mononuclear-cell infiltration and oxidative stress, with concomitant reduction of extracellular matrix/remodeling proteins and heart failure proteins. These data suggest a cardio-protective role of the HO system against L-NAME-induced hypertension that could be explored in the design of novel strategies against cardiomyopathy.

Topics: Adiponectin; Aldosterone; Animals; Antioxidants; Arginine; Atrial Natriuretic Factor; Biomarkers; Blood Pressure; Cardiomyopathies; Cardiotonic Agents; Chemokine CCL2; Chemokine CCL3; Cyclic GMP; Dinoprost; Endothelin-1; Enzyme Induction; Extracellular Matrix Proteins; Heart Failure; Heme; Heme Oxygenase (Decyclizing); Hypertension; Interleukin-1beta; Interleukin-6; Male; NG-Nitroarginine Methyl Ester; Rats; Rats, Sprague-Dawley; Tumor Necrosis Factor-alpha; Tyrosine

Coexistence of chronic kidney disease (CKD) and heart failure (HF) in humans is associated with poor outcome. We hypothesized that preexistent CKD worsens cardiac outcome after myocardial infarction, and conversely that ensuing HF worsens progression of CKD. Subtotally nephrectomized (SNX) or sham-operated (CON) rats were subjected to coronary ligation (CL) or sham surgery in week 9 to realize four groups: CON, SNX, CON + CL, and SNX + CL. Blood pressure and renal function were measured in weeks 8, 11, 13, and 15. In week 16, cardiac hemodynamics and end-organ damage were assessed. Blood pressure was significantly lower in SNX + CL vs. SNX. Despite this, glomerulosclerosis was more severe in SNX + CL vs. SNX. Two weeks after CL, SNX + CL had more cardiac dilatation compared with CON + CL (end-diastolic volume index: 0.28 ± 0.04 vs. 0.19 ± 0.03 ml/100 g body wt; mean ± SD, P < 0.001), although infarct size was similar. During follow-up in SNX + CL, ejection fraction declined. Mortality was only observed in SNX + CL (2 out of 9). In SNX + CL, end-diastolic pressure (18 ± 4 mmHg) and tau (29 ± 9 ms), the time constant of active relaxation, were significantly higher compared with SNX (13 ± 3 mmHg, 20 ± 4 ms; P < 0.01) and CON + CL (11 ± 5 mmHg, 17 ± 2 ms; P < 0.01). The diameter of small arterioles in the myocardium was significantly decreased in SNX + CL vs. CON + CL (P < 0.01). Urinary excretion of NO metabolites was significantly lower in SNX + CL compared with both CL and SNX. This study demonstrates the existence of more heart and more kidney damage in a new model of combined CKD and HF than in the individual models. Such enhanced damage appears to be separate from systemic hemodynamic changes. Reduced nitric oxide availability may have played a role in both worsened glomerulosclerosis and cardiac diastolic function and appears to be a connector in the cardiorenal syndrome.

Topics: Animals; Blood Pressure; Cardio-Renal Syndrome; Coronary Stenosis; Disease Models, Animal; Gene Expression; Heart Failure; Ligation; Male; Myocarditis; Nephrectomy; Nephritis; Nitrates; Nitrites; Peptidyl-Dipeptidase A; Prorenin Receptor; Rats; Rats, Inbred Lew; Receptors, Cell Surface; Renal Insufficiency, Chronic; Renin; Thiobarbituric Acid Reactive Substances; Tyrosine; Ultrasonography

The current study was designed to test the hypothesis that inducible nitric oxide synthase (iNOS)-mediated lipid free radical overproduction exists in an insulin-resistant rat model and that reducing the accumulation of toxic metabolites is associated with improved insulin signaling and metabolic response. Lipid radical formation was detected by electron paramagnetic resonance spectroscopy with in vivo spin trapping in an obese rat model, with or without thiazolidinedione treatment. Lipid radical formation was accompanied by accumulation of toxic end products in the liver, such as 4-hydroxynonenal and nitrotyrosine, and was inhibited by the administration of the selective iNOS inhibitor 1400 W. The model showed impaired phosphorylation of the insulin signaling pathway. Ten-day rosiglitazone injection not only improved the response to an oral glucose tolerance test and corrected insulin signaling but also decreased iNOS levels. Similar to the results with specific iNOS inhibition, thiazolidinedione dramatically decreased lipid radical formation. We demonstrate a novel mechanism where a thiazolidinedione treatment can reduce oxidative stress in this model through reducing iNOS-derived lipid radical formation. Our results suggest that hepatic iNOS expression may underlie the accumulation of lipid end products and that reducing the accumulation of toxic lipid metabolites contributes to a better redox status in insulin-sensitive tissues.

Topics: Aldehydes; Animals; Body Composition; Free Radicals; Glucose Intolerance; Heart Failure; Hypertension; Insulin Resistance; Lipid Peroxidation; Liver; Male; Muscle, Skeletal; Nitric Oxide Synthase Type II; Nitrites; Oxidative Stress; Rats; Rats, Inbred SHR; Rats, Inbred WKY; Thiazolidinediones; Tyrosine

Prominent features of myocardial remodeling in heart failure with preserved ejection fraction (HFPEF) are high cardiomyocyte resting tension (F(passive)) and cardiomyocyte hypertrophy. In experimental models, both reacted favorably to raised protein kinase G (PKG) activity. The present study assessed myocardial PKG activity, its downstream effects on cardiomyocyte F(passive) and cardiomyocyte diameter, and its upstream control by cyclic guanosine monophosphate (cGMP), nitrosative/oxidative stress, and brain natriuretic peptide (BNP). To discern altered control of myocardial remodeling by PKG, HFPEF was compared with aortic stenosis and HF with reduced EF (HFREF).. Patients with HFPEF (n=36), AS (n=67), and HFREF (n=43) were free of coronary artery disease. More HFPEF patients were obese (P<0.05) or had diabetes mellitus (P<0.05). Left ventricular myocardial biopsies were procured transvascularly in HFPEF and HFREF and perioperatively in aortic stenosis. F(passive) was measured in cardiomyocytes before and after PKG administration. Myocardial homogenates were used for assessment of PKG activity, cGMP concentration, proBNP-108 expression, and nitrotyrosine expression, a measure of nitrosative/oxidative stress. Additional quantitative immunohistochemical analysis was performed for PKG activity and nitrotyrosine expression. Lower PKG activity in HFPEF than in aortic stenosis (P<0.01) or HFREF (P<0.001) was associated with higher cardiomyocyte F(passive) (P<0.001) and related to lower cGMP concentration (P<0.001) and higher nitrosative/oxidative stress (P<0.05). Higher F(passive) in HFPEF was corrected by in vitro PKG administration.. Low myocardial PKG activity in HFPEF was associated with raised cardiomyocyte F(passive) and was related to increased myocardial nitrosative/oxidative stress. The latter was probably induced by the high prevalence in HFPEF of metabolic comorbidities. Correction of myocardial PKG activity could be a target for specific HFPEF treatment.

Topics: Aortic Valve Stenosis; Biopsy; Cohort Studies; Comorbidity; Cyclic GMP; Cyclic GMP-Dependent Protein Kinases; Diabetes Mellitus; Female; Heart; Heart Failure; Humans; Male; Middle Aged; Myocardium; Natriuretic Peptide, Brain; Obesity; Oxidative Stress; Stroke Volume; Tyrosine

Hypoxia followed by reoxygenation (H-R) observed during perinatal asphyxia is a serious complication with high mortality and morbidity rates that may cause adverse cardiovascular effects in neonates. Our aim was to determine if oxidative stress related to H-R induces peroxynitrite-dependent modifications of the cardiac contractile protein, myosin regulatory light chain 2 (MLC2), and whether this is associated with development of cardiac systolic dysfunction. Twelve newborn piglets were acutely instrumented for hemodynamic monitoring and randomized to a control group ventilated with only atmospheric air or to the H-R study group exposed to alveolar normocapnic hypoxia followed by reoxygenation. Afterward, animals were euthanized, and the hearts were harvested for biochemical analyses. Systolic function as well as cardiac MLC2 levels decreased in H-R animals, whereas nitrates and nitrotyrosine levels increased. Negative correlations between nitrates, nitrotyrosine, and MLC2 levels were observed. Moreover, H-R induced nitration of two tyrosine residues within the MLC2 protein. Similarly, in vitro exposure of MLC2 to peroxynitrite resulted in the nitration of tyrosine, which increased the susceptibility of MLC2 to subsequent degradation by matrix metalloproteinase 2. Substitution of this tyrosine with phenylalanine prevented the matrix metalloproteinase 2-dependent degradation of MLC2. In addition, a large decrease in MLC2 phosphorylation caused by H-R was observed. Oxidative stress related to asphyxia induces nitration of cardiac MLC2 protein and thus increases its degradation. This and a large decrease in MLC2 phosphorylation contribute to the development of systolic dysfunction. Inhibition of MLC2 nitration and/or direct inhibition of its degradation by MMP-2 could be potential therapeutic targets aiming at reduction of myocardial damage during resuscitation of asphyxiated newborns.

Topics: Animals; Animals, Newborn; Asphyxia Neonatorum; Blotting, Western; Cardiac Myosins; Electrophoresis, Gel, Two-Dimensional; Heart Failure; Hemodynamics; Humans; Immunoprecipitation; Infant, Newborn; Myosin Light Chains; Nitrates; Nitrites; Swine; Tyrosine

Congestive heart failure (CHF) would be associated with mitochondrial abnormalities and increased of reactive species of oxygen (ROS). To clarify these issues we studied the structure, function of the mitochondrial enzyme nitro oxide synthase inducible (iNOS) and lipoperoxidation of membranes, one of their products through the peroxide nitrite ion (ONOO-), in the heart muscle of patients with heart failure congestive (ICC) grade III and IV (according to New York Heart Association). We included 25 patients who underwent cardiovascular surgery to biopsies of the heart muscle. They were stratified into a group with CHF (n = 18) and control group (n = 7). In di-chas biopsies analyzed the enzymatic activity of mitochondrial complex III spectrophotometrically, which was measured in mM.ubiquinona-1.mg prot, while the mitochondrial morphology was analyzed by the Zeiss electron microscope, the areas were quantified with program Axionvision 4.6. Lipoperoxidation of membranes was measured by the presence of ONOO-by immunohistochemistry against primary antibody against 3-nitrotyrosine was used lab kit system biogenic steptobidin biotin peroxidase (SBA) and coloring triamiobencidina (TAB), it is made with semicuantificacion intensity SCORE test. The statistical test used was ANOVA. The heart muscle of patients with CHF showed that the mitochondrial area was reduced by 78% compared with the control (160.37 μm2 ± 9.87) (936.81 μm2 ± 78.48) p 0.0001. There was also a 70% reduction in complex III activity compared to control (1.9 10-2 mM ubiq.mim-prot 1.mg ± 12.6) (5.79 10-2mM ubiq.mim prot-1.mg ± 36.6) p . The presence of ONOO-was significantly increased in patients with CHF. Alterations ultraestructutural and functional mitochondria found in patients with CHF and increased ROS are involved in the measures of physiopathology CCI and whites should be taken into account for future therapies of this condition.

Topics: Adult; Case-Control Studies; Disease Progression; Female; Heart Failure; Humans; Immunohistochemistry; Male; Microscopy, Electron, Transmission; Mitochondria, Heart; Nitric Oxide Synthase Type II; Reactive Oxygen Species; Severity of Illness Index; Tyrosine

The presence of a reciprocal link between inflammation and oxidative/nitrosative stress has been postulated in chronic heart failure (CHF). We aimed to determine signs of nitrosative stress in serum/plasma of CHF patients. ELISA tests were used for quantification of serum/plasma levels of Nitrotyrosine (NT), H(2)O(2), total NO, nitrite (NO(2)(-)), myeloperoxidase (MPO), Tumor Necrosis Factor-alpha (TNFalpha) and pro-Brain Natriuretic Peptide (proBNP) in 66 CHF patients (9 in NYHA I, 34 NYHA II, 23 NYHA III) and in 14 age-matched healthy subjects. NT levels were higher in NYHA III CHF patients compared to NYHA II (p<0.05), NYHA I (p<0.03) and controls (p<0.02), whereas NO(2)(-) and total NO were higher in NYHA III compared to I (p<0.05 and p<0.04, respectively) and controls (p<0.004 and 0.002) and in NYHA II compared to controls (p<0.04 and p<0.009). NT levels correlated significantly with MPO (r=0.37, p<0.003), TNFalpha (r=0.32, p<0.01) and proBNP (r=0.32, p<0.01). These data demonstrate an increased NT plasma level in patients with moderate/severe CHF which is associated to increased levels of markers of systemic inflammation.

Topics: Aged; Biomarkers; Chronic Disease; Cohort Studies; Female; Heart Failure; Humans; Inflammation Mediators; Male; Middle Aged; Peroxidase; Tyrosine

Increased reactive oxygen species (ROS) produced by the failing heart can react with nitric oxide (NO), thereby decreasing NO bioavailability. This study tested the hypothesis that increased ROS generation contributes to coronary endothelial dysfunction in the failing heart. Congestive heart failure (CHF) was produced in six dogs by ventricular pacing at 240 beats/min for 4 wk. Studies were performed at rest and during treadmill exercise under control conditions and after treatment with the NADPH oxidase inhibitor and antioxidant apocynin (4 mg/kg iv). Apocynin caused no significant changes in heart rate, aortic pressure, left ventricular (LV) systolic pressure, LV end-diastolic pressure, or maximum rate of LV pressure increase at rest or during exercise in normal or CHF dogs. Apocynin caused no change in coronary blood flow (CBF) in normal dogs but increased CBF at rest and during exercise in animals with CHF (P < 0.05). Intracoronary ACh caused dose-dependent increases of CBF that were blunted in CHF. Apocynin had no effect on the response to ACh in normal dogs but augmented the response to ACh in CHF dogs (P < 0.05). The oxidative stress markers nitrotyrosine and 4-hydroxy-2-nonenal were significantly greater in failing than in normal myocardium. Furthermore, coelenterazine chemiluminescence for O(2)(-) was more than twice normal in failing myocardium, and this difference was abolished by apocynin. Western blot analysis of myocardial lysates demonstrated that the p47(phox) and p22(phox) subunits of NADPH were significantly increased in the failing hearts, while real-time PCR demonstrated that Nox2 mRNA was significantly increased. The data indicate that increased ROS generation in the failing heart is associated with coronary endothelial dysfunction and suggest that NADPH oxidase may contribute to this abnormality.

Topics: Acetophenones; Acetylcholine; Aldehydes; Animals; Antioxidants; Cardiac Pacing, Artificial; Coronary Circulation; Coronary Vessels; Disease Models, Animal; Dogs; Dose-Response Relationship, Drug; Endothelium, Vascular; Enzyme Inhibitors; Female; Heart Failure; Hemodynamics; Male; NADPH Oxidases; Oxidative Stress; RNA, Messenger; Superoxides; Tyrosine; Up-Regulation; Vasodilation; Vasodilator Agents

Mitochondria of circulating white blood cells (WBC) and platelets sense oxidative stress during capillary passage and react by producing reactive oxygen species (ROS). Although evidence indicates that congestive heart failure (CHF) is associated with oxidative stress, the role of WBC and platelets as mediators in CHF has not been investigated.. Patients with CHF (n = 15) and healthy volunteers (n = 9) were enrolled between 2006 and 2007 into this observational study. Arterial and venous blood samples from participants were incubated with probes to detect cytosolic and mitochondrial ROS. Fluorescence-activated cell sorting was used to measure the degree of fluorescence in WBC and platelets.. Patients with CHF had a higher proportion of ROS-positive arterial WBC and platelets than did controls (67% +/- 47% versus 16% +/- 9%; P <0.005), as well as venous WBC and platelets (77% +/- 43% versus 38% +/- 13%; P <0.01). In the control group, the proportion of cytosolic ROS-positive arterial WBC and platelets was lower than that for ROS-positive venous WBC and platelets (16% +/- 9% versus 38% +/- 13%; P <0.005). CHF patients had a higher proportion of mitochondrial ROS-positive arterial and venous WBC and platelets than did controls.. In CHF, the proportion of WBC and platelets that are ROS-positive is raised, possibly because cytosolic ROS-positive WBC and platelets are normally cleared in the lungs; this function is deficient in CHF while mitochondrial ROS production is increased. The raised numbers of circulating ROS-positive WBC and platelets amplify oxidative stress in CHF.

Topics: Aged; Aged, 80 and over; Biomarkers; Blood Platelets; Case-Control Studies; Cell Separation; Cytosol; Female; Flow Cytometry; Heart Failure; Humans; Leukocytes; Male; Microscopy, Fluorescence; Middle Aged; Mitochondria; Oxidative Stress; Reactive Oxygen Species; Tyrosine

Congestive heart failure (CHF) is a common cause of atrial fibrillation (AF). Oxidative stress and inflammation (profibrotic) and peroxisome proliferator-activated receptor-alpha (PPAR-alpha, antifibrotic) factors may be involved in CHF-related remodeling. We evaluated the effects of simvastatin (antioxidant, anti-inflammatory) and fenofibrate (PPAR-alpha activator) on CHF-related atrial remodeling.. Dogs were subjected to 2-week ventricular tachypacing (VTP) in the absence and presence of simvastatin (20 or 80 mg/day) or fenofibrate. Induced AF duration (DAF) was increased by VTP from 36+/-14 (non-paced controls) to 1005+/-257 s (p<0.01). Simvastatin prevented VTP-induced DAF increases (147+/-37 and 84+/-37 s at 20 and 80 mg/day, respectively), but fenofibrate did not (1018+/-352 s). Simvastatin also attenuated CHF-induced conduction abnormalities (heterogeneity-index reduced from 1.5+/-0.1 to 1.1+/-0.1 and 1.0+/-0.1 at 20 and 80 mg/day, p<0.01) and atrial fibrosis (from 19.4+/-1.3% to 10.8+/-0.8% and 9.9+/-0.8% at 20 and 80 mg/day, p<0.01), while fenofibrate did not. Simvastatin (but not fenofibrate) also attenuated VTP-induced left-ventricular nitric-oxide synthase and nitrotyrosine increases, along with hemodynamic dysfunction. Atrial fibroblast proliferation increased with 24-h fetal bovine serum (FBS) stimulation from 654+/-153 to 7264+/-1636 DPM (p<0.001). Simvastatin, but not fenofibrate, suppressed fibroblast proliferation (664+/-192 DPM, p<0.001). Simvastatin also significantly attenuated transforming growth factor-beta1-stimulated alpha-smooth muscle actin (alpha-SMA) expression (indicating myofibroblast differentiation) from 1.3+/-0.1 to 1.0+/-0.1 times baseline (p<0.05).. CHF-induced atrial structural remodeling and AF promotion are attenuated by simvastatin, but not fenofibrate. Statin-induced inhibition of profibrotic atrial fibroblast responses and attenuation of left-ventricular dysfunction may contribute to preventing the CHF-induced fibrotic AF substrate.

Topics: Actins; Animals; Anti-Inflammatory Agents; Atrial Fibrillation; Biomarkers; Cardiac Pacing, Artificial; Cell Proliferation; Cells, Cultured; Dogs; Fenofibrate; Fibroblasts; Heart Atria; Heart Failure; Heart Ventricles; Hypolipidemic Agents; Models, Animal; Nitric Oxide Synthase Type II; Nitric Oxide Synthase Type III; PPAR alpha; Refractory Period, Electrophysiological; Simvastatin; Tyrosine; Ventricular Remodeling

Oxidative stress is an important susceptibility factor for dilated cardiomyopathy. We have investigated the effects of bisoprolol, a beta1-selective adrenoceptor blocker, on oxidative stress and the development of cardiac dysfunction in a model of dilated cardiomyopathy. Male TO-2 and control hamsters at 8 weeks of age were treated with bisoprolol (5 mg/kg per day) or vehicle for 4 weeks. Treatment with bisoprolol prevented the progression of cardiac dysfunction in TO-2 hamsters. This drug did not affect the increase in NADPH oxidase activity but prevented the reduction in activity and expression of mitochondrial manganese-dependent superoxide dismutase as well as the increases in the concentrations of interleukin-1beta and tumor necrosis factor-alpha in the left ventricle of TO-2 hamsters. Attenuation of the development of cardiac dysfunction by bisoprolol may thus result in part from normalization of the associated increases in the levels of oxidative stress and pro-inflammatory cytokines in the left ventricle.

Topics: Aldehydes; Animals; Antioxidants; Bisoprolol; Blood Pressure; Body Weight; Cardiomyopathy, Dilated; Cricetinae; Disease Models, Animal; Echocardiography; Fibrosis; Glutathione; Heart Failure; Heart Rate; Interleukin-1; Isoenzymes; Male; NADPH Oxidases; Organ Size; Oxidative Stress; Superoxide Dismutase; Tumor Necrosis Factor-alpha; Tyrosine; Ventricular Function, Left

Vascular endothelial functions, other than nitric oxide (NO)-mediated control of vasomotor tone, are poorly characterized in patients with chronic heart failure (CHF). Veins and arteries are exposed to the same circulating proinflammatory mediators in patients with CHF. The present study tested whether endothelial cell activation occurs in veins of patients with decompensated CHF and whether activation, if present, subsides with return to a clinically compensated state.. Fifteen patients with decompensated CHF requiring transient inotropic support and 6 age-matched, healthy controls were studied. Endothelial cells and blood were collected from a forearm vein, and brachial artery flow-mediated dilation (FMD) was measured before and 24 hours after discontinuation of short-term inotropic therapy, when patients had returned to a steady compensated state. Nitrotyrosine immunoreactivity (an intracellular marker of oxidative stress), cyclooxygenase-2 (COX-2), and inducible NO synthase (iNOS) expression were significantly higher in venous endothelial cells of patients in clinical decompensation when compared with healthy subjects. Return to a compensated state resulted in a significant reduction in nitrotyrosine immunoreactivity, COX-2, and iNOS expression. Concomitantly, a significant increase in FMD and a decline in plasma total 8-isoprostane and bicycloprostaglandin E2 levels were observed. Venous endothelial NOS expression was unaffected by clinical decompensation.. Clinical decompensation in CHF is associated with activation of the venous endothelium. Return to a compensated state after short-term inotropic therapy results in a significant reduction in endothelial nitrotyrosine formation, COX-2, and iNOS expression.

Topics: Adult; Aged; Brachial Artery; Cardiotonic Agents; Cells, Cultured; Cyclooxygenase 2; Dinoprost; Dinoprostone; Endothelium, Vascular; Enzyme Induction; Female; Heart Failure; Humans; Male; Membrane Proteins; Middle Aged; Nitric Oxide Synthase; Nitric Oxide Synthase Type II; Nitric Oxide Synthase Type III; Oxidative Stress; Prostaglandin-Endoperoxide Synthases; Tyrosine; Vasodilation; Veins

Although aldosterone, acting via mineralocorticoid receptors, causes left ventricular (LV) hypertrophy in experimental models of high-aldosterone hypertension, little is known about the role of aldosterone or mineralocorticoid receptors in mediating adverse remodeling in response to chronic pressure overload.. We used the mineralocorticoid receptor-selective antagonist eplerenone (EPL) to test the role of mineralocorticoid receptors in mediating the transition from hypertrophy to failure in mice with chronic pressure overload caused by ascending aortic constriction (AAC). One week after AAC, mice were randomized to regular chow or chow containing EPL (200 mg/kg per day) for an additional 7 weeks. EPL had no significant effect on systolic blood pressure after AAC. Eight weeks after AAC, EPL treatment improved survival (94% versus 65%), attenuated the increases in LV end-diastolic (3.4+/-0.1 versus 3.7+/-0.1 mm) and end-systolic (2.0+/-0.1 versus 2.5+/-0.2 mm) dimensions, and ameliorated the decrease in fractional shortening (42+/-2% versus 34+/-4%). EPL also decreased myocardial fibrosis, myocyte apoptosis, and the ratio of matrix metalloproteinase-2/tissue inhibitor of matrix metalloproteinase-2. These beneficial effects of EPL were associated with less myocardial oxidative stress, as assessed by 3-nitrotyrosine staining, reduced expression of the adhesion molecule intercellular adhesion molecule-1, and reduced infiltration by macrophages.. Mineralocorticoid receptors play an important role in mediating the transition from LV hypertrophy to failure with chronic pressure overload. The effects of mineralocorticoid receptor stimulation are associated with alterations in the interstitial matrix and myocyte apoptosis and may be mediated, at least in part, by oxidative stress and inflammation.

Topics: Animals; Aorta; Apoptosis; Blood Pressure; Cell Size; Chronic Disease; Constriction, Pathologic; Drug Evaluation, Preclinical; Eplerenone; Fibrosis; Heart Failure; Hypertrophy, Left Ventricular; Intercellular Adhesion Molecule-1; Ligation; Male; Matrix Metalloproteinases; Mice; Mineralocorticoid Receptor Antagonists; Myocarditis; Myocardium; Myocytes, Cardiac; Oxidative Stress; Pressure; Random Allocation; Receptors, Mineralocorticoid; Spironolactone; Tissue Inhibitor of Metalloproteinase-1; Tissue Inhibitor of Metalloproteinase-2; Tyrosine

Reduced sarcoplasmic reticulum (SR) Ca2+-ATPase (SERCA2a isoform) activity is a major determinant of reduced contractility in heart failure. Ca2+-ATPase inactivation can occur through SERCA2a nitration. We therefore investigated the role of SERCA2a nitration in heart failure.. We measured SERCA2a levels and nitrotyrosine levels in tissue from normal and failing human hearts using Western blots. We found that nitrotyrosine levels in idiopathic dilated cardiomyopathic (DCM) hearts were almost double those of control hearts in age-matched groups. Nitrotyrosine was dominantly present in a single protein with the molecular weight of SERCA2a, and immunoprecipitation confirmed that the protein recognized by the nitrotyrosine antibody was SERCA2a. There was a positive correlation between the time to half relaxation and the nitrotyrosine/SERCA2a content (P<0.01) in myocytes isolated from control and DCM hearts. In experiments with isolated SR vesicles from porcine hearts, we also showed that the Ca pump is inactivated by peroxynitrite exposure, and inactivation was prevented by protein kinase A pretreatment.. We conclude that SERCA2a inactivation by nitration may contribute to Ca pump failure and hence heart failure in DCM.

Topics: Adolescent; Adult; Blotting, Western; Calcium-Transporting ATPases; Female; Heart Failure; Heart Ventricles; Humans; Isoenzymes; Male; Middle Aged; Myocardium; Myocytes, Cardiac; Phosphorylation; Sarcoplasmic Reticulum; Sarcoplasmic Reticulum Calcium-Transporting ATPases; Tyrosine

Topics: Biomarkers; Cells, Cultured; Heart Failure; Humans; Myocardial Contraction; Myocardial Reperfusion Injury; Myocardium; Peroxynitrous Acid; Tyrosine

We investigated the effects of a novel ultrapotent poly(adenosine diphosphate-ribose) polymerase (PARP) inhibitor, PJ34, on cardiac and endothelial dysfunction in a rat model of chronic heart failure (CHF).. Overactivation of the nuclear enzyme PARP importantly contributes to the development of cell dysfunction and tissue injury in various pathophysiologic conditions associated with oxidative stress, including myocardial reperfusion injury, heart transplantation, stroke, shock, and diabetes.. Chronic heart failure was induced in Wistar rats by chronic ligation of the left anterior descending coronary artery. Left ventricular (LV) function and ex vivo vascular contractility and relaxation were measured 10 weeks after the surgery. Nitrotyrosine (NT) formation and PARP activation were detected by immunohistochemistry.. Chronic heart failure induced increased NT formation and PARP activation in the myocardium and intramural vasculature, depressed LV performance, and impaired vascular relaxation of aortic rings. PJ34 significantly decreased myocardial PARP activation but not NT formation, and improved both cardiac dysfunction and vascular relaxation.. Poly(ADP-ribose) polymerase inhibition represents a novel approach for the experimental treatment of CHF.

Topics: Animals; Enzyme Activation; Enzyme Inhibitors; Heart Failure; Immunohistochemistry; Male; Phenanthrenes; Poly(ADP-ribose) Polymerase Inhibitors; Rats; Rats, Wistar; Tyrosine; Vasomotor System; Ventricular Function, Left

Oxidative stress is implicated in the initiation and progression of congestive heart failure, but the putative reactive species and cellular targets involved remain undefined. We have previously shown that peroxynitrite (ONOO(-), an aggressive biological oxidant and nitrating agent) potently inhibits myofibrillar creatine kinase (MM-CK), a critical controller of contractility known to be impaired during heart failure. Here we hypothesized that nitration and inhibition of MM-CK participate in cardiac failure in vivo.. Heart failure was induced in rats by myocardial infarction (left coronary artery ligation) and confirmed by histological analysis at 8 weeks postinfarct (1.3+/-1.4 vs. 37.7+/-3.2% left ventricular circumference; sham control vs. CHF, n=10 each).. Immunohistochemistry demonstrated significantly increased protein nitration in failing myocardium compared to control (optical density: 0.58+/-0.06 vs. 0.93+/-0.09, sham vs. CHF, P<0.05). Significant decreases in MM-CK activity and content were observed in failing hearts (MM-CK k(cat): 6.0+/-0.4 vs. 3.0+/-0.3 micromol/nM M-CK/min, P<0.05; 6.8+/-1.3 vs. 4.7+/-1.2% myofibrillar protein, P<0.05), with no change in myosin ATPase activity. In separate experiments, isolated rat cardiac myofibrils were exposed to ONOO(-) (2-250 microM) and enzyme studies were conducted. Identical to in vivo studies, selective reductions in MM-CK were observed at ONOO(-) concentrations as low as 2 microM (IC(50)=92.5+/-6.0 microM); myosin ATPase was unaffected with ONOO(-) concentrations as high as 250 microM. Concentration dependent nitration of MM-CK occurred and extent of nitration was statistically correlated to extent of CK inhibition (P<0.001). Immunoprecipitation of MM-CK from failing left ventricle yielded significant evidence of tyrosine nitration.. These data demonstrate that cardiac ONOO(-) formation and perturbation of myofibrillar energetic controllers occur during experimental heart failure; MM-CK may be a critical cellular target in this setting.

Topics: Animals; Creatine Kinase; Creatine Kinase, MM Form; Heart Failure; Image Processing, Computer-Assisted; Immunohistochemistry; Isoenzymes; Male; Myofibrils; Myosins; Nitrates; Oxidants; Rats; Rats, Sprague-Dawley; Tyrosine

Hydroxymethylglutaryl coenzyme A reductase inhibitors (statins) attenuate angiotensin II-induced cellular signaling. Because angiotensin II is involved in left ventricular (LV) remodeling after myocardial infarction (MI), we examined the effects of statin treatment in an experimental model of chronic heart failure after MI.. Rats with extensive MI were treated with placebo or cerivastatin (0.3 mg/kg per day) as a dietary supplement or via gavage for 11 weeks starting on the 7th postoperative day. Infarct size and cholesterol levels were similar among all groups. LV cavity area, an index of LV dilatation, was reduced in MI rats on cerivastatin compared with placebo. LV end-diastolic pressure was increased in MI rats on placebo (24.1+/-4.1 mm Hg versus sham: 5.1+/-0.3 mm Hg; P<0.01), and it was significantly reduced by cerivastatin treatment (13.7+/-2.7 mm Hg; P<0.05 versus placebo). Cerivastatin partially normalized LV dP/dt(max) and dP/dt(min), indices of LV systolic and diastolic function, which were significantly reduced in MI rats on placebo. Improvement of LV function by cerivastatin was accompanied by a reduced expression of collagen type I and beta-myosin heavy chain. LV endothelial nitric oxide synthase was increased, whereas the nitrotyrosine protein level was decreased in MI rats by cerivastatin treatment.. Cerivastatin improved LV remodeling and function in rats with heart failure. This effect was associated with an attenuated LV expression of fetal myosin heavy chain isoenzymes and collagen I. Statin treatment may retard the progression of chronic heart failure.

Topics: Animals; Blotting, Northern; Blotting, Western; Collagen; Gene Expression Regulation; Heart Failure; Heart Ventricles; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Male; Myocardial Contraction; Myocardial Infarction; Myosin Heavy Chains; Nitric Oxide Synthase; Nitric Oxide Synthase Type III; Pyridines; Rats; Rats, Wistar; RNA, Messenger; Tyrosine

The renin-angiotensin system is upregulated with diabetes, and this may contribute to the development of a dilated myopathy. Angiotensin II (Ang II) locally may lead to oxidative damage, activating cardiac cell death. Moreover, diabetes and hypertension could synergistically impair myocardial structure and function. Therefore, apoptosis and necrosis were measured in ventricular myocardial biopsies obtained from diabetic and diabetic-hypertensive patients. Accumulation of a marker of oxidative stress, nitrotyrosine, and Ang II labeling were evaluated quantitatively. The diabetic heart showed cardiac hypertrophy, cavitary dilation, and depressed ventricular performance. These alterations were more severe with diabetes and hypertension. Diabetes was characterized by an 85-fold, 61-fold, and 26-fold increase in apoptosis of myocytes, endothelial cells, and fibroblasts, respectively. Apoptosis in cardiac cells did not increase additionally with diabetes and hypertension. Diabetes increased necrosis by 4-fold in myocytes, 9-fold in endothelial cells, and 6-fold in fibroblasts. However, diabetes and hypertension increased necrosis by 7-fold in myocytes and 18-fold in endothelial cells. Similarly, Ang II labeling in myocytes and endothelial cells increased more with diabetes and hypertension than with diabetes alone. Nitrotyrosine localization in cardiac cells followed a comparable pattern. In spite of the difference in the number of nitrotyrosine-positive cells with diabetes and with diabetes and hypertension, apoptosis and necrosis of myocytes, endothelial cells, and fibroblasts were detected only in cells containing this modified amino acid. In conclusion, local increases in Ang II with diabetes and with diabetes and hypertension may enhance oxidative damage, activating cardiac cell apoptosis and necrosis.

Topics: Angiotensin II; Apoptosis; Cardiomegaly; Diabetes Mellitus, Type 2; Female; Heart Failure; Humans; Hypertension; Male; Middle Aged; Oxidative Stress; Reactive Oxygen Species; Renin-Angiotensin System; Tyrosine