Allopurinol reduces B-type natriuretic peptide concentrations and haemoglobin but does not alter exercise capacity in chronic heart failure

OBJECTIVE

To study whether the effect of allopurinol on improvement of endothelial dysfunction in chronic heart failure (CHF) translates into improved exercise capacity and to examine whether allopurinol also improves B-type natriuretic peptide (BNP), the other important prognostic marker of CHF.

DESIGN

Randomised, double blind, placebo controlled crossover trial.

SETTING

Teaching hospital.

PATIENTS

50 patients with CHF (New York Heart Association functional classes II and III) were recruited.

INTERVENTIONS

50 patients with CHF were randomly assigned to three months' treatment with allopurinol (300 mg/day) or placebo. At two and three months into treatment, they underwent a modified Bruce exercise protocol and a six minute walk test. Blood was taken for BNP and haemoglobin analysis.

RESULTS

Neither exercise test was altered by allopurinol. However, plasma BNP concentrations fell significantly (p = 0.035) with allopurinol (11.9 pmol/l) versus placebo (14.4 pmol/l). Haemoglobin concentrations also fell highly significantly with allopurinol (p = 0.001).

CONCLUSIONS

An important negative finding is that despite high hopes for it, allopurinol had no effect on exercise capacity in CHF. On the other hand, allopurinol did reduce BNP, which is the best available surrogate marker for prognosis in CHF.

Increased risk of heart failure as a consequence of perioperative myocardial injury after coronary artery bypass grafting

OBJECTIVE

To analyse the relation between perioperative myocardial injury (PMI) and the risk of subsequent heart failure after coronary artery bypass grafting (CABG).

DESIGN AND SETTING

Clinical data were documented prospectively in all patients and stored in a computer. All hospital readmissions were identified and the registered primary diagnoses were analysed. Survival information on all patients was obtained by use of combined registers. The study was carried out at the cardiac surgical referral centre of University Hospital, Uppsala, Sweden.

PATIENTS

7493 patients discharged alive after primary CABG between 1987 and 1996 were followed up until the first hospital readmission for heart failure, death, or 31 December 1996 was reached.

MAIN OUTCOME MEASURES

Hospital readmission for heart failure or late mortality.

RESULTS

Of the patients studied 576 (7.7%) were readmitted for heart failure. Actuarial freedom from readmission for heart failure after four years was 93%, and after seven years, 89%. Of the 576 patients, 114 (20%) had had PMI, which increased the risk of heart failure independently (hazard ratio (HR) 2.3, 95% confidence interval (CI) 1.8 to 2.8). Increased age, female sex, diabetes, previous myocardial infarction, dyspnoea, preoperative atrial fibrillation, left ventricular dysfunction, and triple vessel disease were independent risk factors for heart failure. The use of an internal mammary artery decreased the risk. PMI implied increased mortality (HR 1.4, 95% CI 1.1 to 1.8). Late mortality was greatly increased in patients readmitted for heart failure.

CONCLUSION

PMI increased the risk of heart failure and late death after CABG, and heart failure had a notable adverse effect on late survival.

Carnitine palmitoyl transferase-I inhibition prevents ventricular remodeling and delays decompensation in pacing-induced heart failure

OBJECTIVE

Experimental evidence suggests that modulation of myocardial substrate metabolism can markedly affect the progression of chronic heart failure (HF). We tested whether the inhibition of carnitine palmitoyl transferase-I (CPT-I), the enzyme regulating mitochondrial fatty acid oxidation, slows left ventricular remodeling and deterioration of function in pacing-induced HF.

METHODS

Normal dogs (n=9) were compared to untreated dogs with pacing-induced HF (n=9) and HF dogs treated with 65 mg/kg/day of oxfenicine (HF+Oxf, n=9), a CPT-I inhibitor.

RESULTS

HF+Oxf reached terminal failure (LV end-diastolic pressure=25 mm Hg) 6 days later than untreated HF (P<0.05). At 28 days of pacing, hemodynamic alterations and LV dilation were significantly attenuated and the 25% decrease in LV wall thickness was completely prevented in HF+Oxf vs. untreated HF, as was the activation of matrix metalloproteinase-2 and -9, markers of tissue remodeling. Oxfenicine also prevented HF-induced transcriptional down-regulation of CPT-I, medium chain acyl-CoA dehydrogenase, GAPDH and citrate synthase, key enzymes of cardiac energy metabolism. In addition, mRNA, but not protein levels of the nuclear receptor peroxisome proliferator-activated receptor-alpha were reduced in untreated HF, while they did not change significantly in HF+Oxf, as compared to control.

CONCLUSIONS

CPT-I inhibition early in the development of HF prevented LV wall thinning and delayed the time to end-stage failure. While these results are limited to an experimental model of disease, they nevertheless suggest that CPT-I inhibition might be effective for slowing the progression of clinical HF.

Statin-induced improvement of endothelial progenitor cell mobilization, myocardial neovascularization, left ventricular function, and survival after experimental myocardial infarction requires endothelial nitric oxide synthase

BACKGROUND

Endothelial nitric oxide (eNO) bioavailability is severely reduced after myocardial infarction (MI) and in heart failure. Statins enhance eNO availability by both increasing eNO production and reducing NO inactivation. We therefore studied the effect of statin treatment on eNO availability after MI and tested its role for endothelial progenitor cell mobilization, myocardial neovascularization, left ventricular (LV) dysfunction, remodeling, and survival after MI.

METHODS AND RESULTS

Wild-type (WT) and eNO synthase (eNOS)-/- mice with extensive anterior MI were randomized to treatment with vehicle (V) or atorvastatin (Ator, 50 mg/kg QD by gavage) for 4 weeks starting on day 1 after MI. Ator markedly improved endothelium-dependent, NO-mediated vasorelaxation; mobilization of endothelial progenitor cells; and myocardial neovascularization of the infarct border in WT mice after MI while having no effect in eNOS-/- mice. LV dysfunction and interstitial fibrosis were markedly attenuated by Ator in WT mice, whereas no effect was observed in eNOS-/- mice after MI. Importantly, Ator significantly increased the survival rate during 4 weeks after MI in WT mice (Ator versus V, 80% versus 46%; P<0.01, n=75) but not in eNOS-/- mice (43% versus 48%; NS, n=42).

CONCLUSIONS

These findings suggest that increased eNO availability is required for statin-induced improvement of endothelial progenitor cell mobilization, myocardial neovascularization, LV dysfunction, interstitial fibrosis, and survival after MI. eNO bioavailability after MI likely represents an important therapeutic target in heart failure after MI and mediates beneficial effects of statin treatment after MI.

Ventricular Assist Device Therapy Normalizes Inducible Nitric Oxide Synthase Expression and Reduces Cardiomyocyte Apoptosis in the Failing Human Heart

OBJECTIVES

We examined the effect of mechanical unloading with ventricular assist device (VAD) therapy on myocardial inducible nitric oxide synthase (iNOS) expression and cardiomyocyte apoptosis in patients with end-stage heart failure (HF).

BACKGROUND

Despite advances in medical therapy, HF continues to be a progressive and ultimately fatal disorder. High levels of iNOS expression are present in the myocardium of failing hearts, suggesting a potential role for iNOS in HF progression.

METHODS

Inducible NOS protein expression was analyzed by Western blotting and cardiomyocyte apoptosis by terminal deoxynucleotidyltransferase dUTP nick end-labeling (TUNEL) in myocardial samples from failing hearts. Included in these analyses were tissues from 9 patients at the time of transplantation (HF-transplant group), 10 patients at the time of VAD insertion (pre-VAD group), and 11 patients undergoing transplant after VAD support (post-VAD group). Seven control samples were obtained at autopsy.

RESULTS

Low or undetectable levels of iNOS were present in controls (0.005 +/- 0.002). The HF-transplant and pre-VAD myocardial specimens exhibited a marked increase in iNOS expression (1.48 +/- 0.34 and 1.29 +/- 0.26, respectively; p < 0.01 for both vs. controls). The increase in iNOS expression was reversed in the post-VAD group (0.36 +/- 0.16; p < 0.01 vs. HF-transplant and pre-VAD groups). The rate of TUNEL-positive cardiomyocytes was high in the pre-VAD group and significantly lower in the post-VAD group (0.64 +/- 0.15% in pre-VAD group and 0.16 +/- 0.07% in post-VAD group; p < 0.01). The iNOS levels correlated significantly with cardiomyocyte apoptosis (r = 0.66, p < 0.01).

CONCLUSIONS

Therapy with VAD normalizes iNOS expression in association with diminished cardiomyocyte apoptosis in the failing heart. Further work is required to define whether a causal relationship exists between iNOS and cardiomyocyte apoptosis.

[Myocardial effects of nitric oxide, NO. Clinical and experimental evidence]

The vasodilatory properties of nitric oxide (NO) are well documented, but its direct effects on myocardial contractility are somewhat controversial. The present report follows a series of articles in which we reported the translocation of NO synthase isoforms both after myocardial infarction in aged rats and in human heart failure (HF). This redistribution is due to nNOS1 translocation from the sarcoplasmic reticulum to the caveolae in the outer membranes. Translocation is determined by strong interactions between the enzyme and caveoline-3 (a marker of caveolae). It suggests a regulatory role of nNOS1 in both normal inotropism and HF. The physiological consequences of this translocation were studied in a well-documented experimental model of myocardial infarction with HF in adult rats. Myocardial function was analyzed before and after adrenergic activation, both ex vivo on isolated hearts and in vivo with a Millar probe.--In rats, as in humans, the level of nNOS1 is enhanced, and this is associated with translocation to the caveolae. Such a process is seen in both humans and rats with HF.--In HF, ventricular elastance (E(s), in mmHg/microL: a load-independent measure of contractility) is reduced, and the time constant of relaxation, tau, is prolonged. In basal conditions, in non HF controls, specific nNOS1 inhibition by L-VNIO induces a 33% increase in E(s) and a 17% increase in the time constant of relaxation. The response to an adrenergic stimulation is attenuated in HF. The main result of this work is that pharmacological inhibition of nNOS1, either ex vivo with L-VNIO, or in vivo with SMTC, normalizes the adrenergic response of failing hearts. nNOS1 translocation is thus a major contributor to the autocrine regulation of contractility in HF, and is probably responsible for hampering the adrenergic response in HF.

Myocardial expression and redistribution of GRKs in hypertensive hypertrophy and failure

G-protein-coupled receptor kinases (GRKs) are involved in cardiac hypertrophy and failure. But their temporal expression and cellular localization during the development of hypertrophy and its transition to failure remains to be investigated. In this study, we determined the expression and subcellular distribution of GRK2, GRK3, GRK5, and GRK6 in cardiac myocytes of 2- to 24-month-old spontaneously hypertensive heart failure (SHHF) rats. GRK2 increased in the intercalated disks in 6-, 12-, and 24-month-old SHHF rats, although total expression remained relatively constant from 2 to 24 months in both SHHF and normotensive rats. GRK3 expression progressively increased in 6-, 12-, and 24-month-old SHHF rats and was significantly higher than in age-matched controls. Immunolabeling of GRK3 showed a typical pattern of cross-striations that colocalized with alpha-actinin and G(alphas) at Z-lines in both SHHF and control rats. GRK5 expression showed no change from 2 to 24 months in both SHHF and normotensive rats. Confocal analysis revealed nuclear translocation of GRK5 in myocytes of SHHF rats. GRK6 had a striated pattern colocalized with alpha-actinin at Z-lines in the cytoplasm and was also present in the intercalated disks of cardiac myocytes from both SHHF and control rats. GRK6 expression increased in 12- and 24-month-old SHHF rats and was significantly higher than in age-matched controls. GRK6 labeling was reduced at the intercalated disks, but increased in the cytoplasm of cardiac myocytes from SHHF rats compared to age-matched controls. The increased expression of GRK3 and GRK6 and subcellular redistribution of GRK2, GRK5, and GRK6 in SHHF rats may be involved in abnormal remodeling of cardiac myocytes in hypertensive hypertrophy and failure.

Na+-K+-ATPase properties in rat heart and skeletal muscle 3 mo after coronary artery ligation

This study was designed to determine whether chronic heart failure (CHF) results in changes in Na(+)-K(+)-ATPase properties in heart and skeletal muscles of different fiber-type composition. Adult rats were randomly assigned to a control (Con; n = 8) or CHF (n = 8) group. CHF was induced by ligation of the left main coronary artery. Examination of Na(+)-K(+)-ATPase activity (means +/- SE) 12 wk after the ligation measured, using the 3-O-methylfluorescein phosphatase assay (3-O-MFPase), indicated higher (P < 0.05) levels in soleus (Sol) (250 +/- 13 vs. 179 +/- 18 nmol.mg protein(-1).h(-1)) and lower (P < 0.05) levels in diaphragm (Dia) (200 +/- 12 vs. 272 +/- 27 nmol.mg protein(-1).h(-1)) and left ventricle (LV) (760 +/- 62 vs. 992 +/- 16 nmol.mg protein(-1).h(-1)) in CHF compared with Con, respectively. Na(+)-K(+)-ATPase protein content, measured by the [(3)H]ouabain binding technique, was higher (P < 0.05) in white gastrocnemius (WG) (166 +/- 12 vs. 135 +/- 7.6 pmol/g wet wt) and lower (P < 0.05) in Sol (193 +/- 20 vs. 260 +/- 8.6 pmol/g wet wt) and LV (159 +/- 10 vs. 221 +/- 10 pmol/g wet wt) in CHF compared with Con, respectively. Isoform content in CHF, measured by Western blot techniques, showed both increases (WG; P < 0.05) and decreases (Sol; P < 0.05) in alpha(1). For alpha(2), only increases [red gastrocnemius (RG), Sol, and Dia; P < 0.05] occurred. The beta(2)-isoform was decreased (LV, Sol, RG, and WG; P < 0.05) in CHF, whereas the beta(1) was both increased (WG and Dia; P < 0.05) and decreased (Sol and LV; P < 0.05). For beta(3), decreases (P < 0.05) in RG were observed in CHF, whereas no differences were found in Sol and WG between CHF and Con. It is concluded that CHF results in alterations in Na(+)-K(+)-ATPase that are muscle specific and property specific. Although decreases in Na(+)-K(+)-ATPase content would appear to explain the lower 3-O-MFPase in the LV, such does not appear to be the case in skeletal muscles where a dissociation between these properties was observed.

G-protein-coupled receptor kinase activity in human heart failure: effects of beta-adrenoceptor blockade

OBJECTIVES

In human end-stage heart failure as well as in experimental animal models of heart failure, G-protein-coupled receptor kinase activity (GRK) is increased while beta-adrenoceptor responsiveness is diminished. In animal studies, beta-adrenoceptor blockers reverse the GRK-mediated desensitization and down-regulation of myocardial beta-adrenoceptors. The aim of this study was to investigate whether alterations in GRK activity are an early or late accompaniment of human heart failure and whether also in humans beta-adrenoceptor blocker treatment is able to influence myocardial GRK activity.

METHODS

We assessed in right atria, obtained from patients at different stages of heart failure, treated with or not treated with beta-adrenoceptor blockers, and in the four chambers of explanted hearts, obtained from patients with end-stage heart failure, beta-adrenoceptor density (by (-)-[(125)I]-iodocyanopindolol binding) and GRK activity (by an in vitro rhodopsin phosphorylation assay).

RESULTS

With increasing severity of heart failure, plasma noradrenaline levels increased while myocardial beta-adrenoceptor density decreased with a maximum in GRK activity in end-stage heart failure. However, in relation to the progression of heart failure, we found that GRK activity transiently increased at an early stage of heart failure (NYHA I and II) but decreased back to control values in patients at NYHA III and IV. beta-Adrenoceptor blockers were able to reduce the early increase in GRK activity at NYHA I and II to control levels, whereas in those patients who did not have increased GRK activity (NYHA III and IV), they had only a marginal effect.

CONCLUSION

According to our results, an increase in GRK activity is an early and transient event in the course of heart failure that can be prevented by beta-adrenoceptor blocker treatment.

Antioxidative effects of exercise training in patients with chronic heart failure: increase in radical scavenger enzyme activity in skeletal muscle

BACKGROUND

In chronic heart failure (CHF), cross-talk between inflammatory activation and oxidative stress has been anticipated in skeletal muscle (SM). The role of the radical scavenger enzymes superoxide dismutase (SOD), catalase (Cat), and glutathione peroxidase (GPX), which remove oxygen radicals, has never been assessed in the SM in this context. Moreover, it remains unknown whether exercise training augments the activity of these enzymes in CHF.

METHODS AND RESULTS

Twenty-three patients with CHF were randomized to either 6 months of exercise training (T) or a sedentary lifestyle (C); 12 age-matched healthy subjects (HS) were studied in parallel. Activity of Cat, SOD, and GPX was assessed in SM biopsies before and after 6 months (6 months). Oxidative stress was determined by measuring nitrotyrosine formation. SOD, Cat, and GPX activity was reduced by 31%, 57%, and 51%, respectively, whereas nitrotyrosine formation was increased by 107% in SM in CHF (P<0.05 versus HS). In CHF, exercise training augmented GPX and Cat activity in SM by 41% (P<0.05 versus before and group C) and 42% (P<0.05 versus before and group C), respectively, and decreased nitrotyrosine production by 35% (from 3.8+/-0.4% tissue area before to 2.5+/-0.3% after 6 months; P<0.05 versus before).

CONCLUSIONS

The reduced activity of major antioxidative enzymes in the SM of CHF patients is associated with increased local oxidative stress. Exercise training exerts antioxidative effects in the SM in CHF, in particular, due to an augmentation in activity of radical scavenger enzymes.

Enhanced matrix metalloproteinase activity in skeletal muscles of rats with congestive heart failure

Patients with congestive heart failure (CHF) are prone to increased skeletal muscle fatigue. Elevated circulatory concentrations of tumor necrosis factor (TNF)-alpha and monocyte chemoattractant protein-1, which may stimulate matrix metalloproteinase (MMP) activity and, thereby, contribute to skeletal muscle dysfunction, are frequently found in CHF. However, whether skeletal muscle MMP activity is altered in CHF is unknown. Hence, we have used a gelatinase assay to assess the activity of MMP and tissue inhibitors of MMP in single skeletal muscles of rats with CHF 6 wk after induction of myocardial infarction. Sham-operated (Sham) rats were used as controls. We also measured the gene expression and protein contents of MMP-2 and MMP-9 in skeletal muscles of these rats. Plasma MMP activity was nearly seven times higher (P < 0.05) in CHF than in Sham rats. Concomitantly, the MMP activity within single slow- and fast-twitch skeletal muscles of CHF rats increased two- to fourfold compared with Sham animals, whereas tissue inhibitor of MMP activity did not differ (P > 0.05). Preformed MMP-2 and MMP-9 were probably activated in CHF, because neither their gene expression nor protein levels were altered (P > 0.05). Serum concentrations of TNF-alpha and monocyte chemoattractant protein-1 remained unchanged (P > 0.05) between CHF and Sham rats during the 6-wk observation period. We conclude that development of CHF in rats enhances MMP activity, which in turn may distort the normal contractile function of skeletal muscle, thereby contributing to increased skeletal muscle fatigue.

Plasma concentrations of tumour dimeric pyruvate kinase are increased in patients with chronic cardiac failure

BACKGROUND

The aim of the study was to assess the effect of chronic cardiac failure (CCF) on circulating plasma concentrations of tumour metabolic marker dimeric pyruvate kinase type M2 (M2-PK).

METHODS

Fifty patients with clinically stable CCF were studied. Patients with a history of past or ongoing malignancy were excluded. Dimeric M2-PK was measured by enzyme-linked immunosorbent assay in EDTA plasma.

RESULTS

Dimeric M2-PK concentration increased significantly (P = 0.005) with increasing clinical severity of CCF as assessed by the New York Heart Association classification grade.

CONCLUSIONS

Chronic cardiac failure results in an increased circulating plasma concentration of M2-PK, probably related to increased glycolytic flux. The physiological significance of the results is at present unclear but may relate to maintaining a balance between energy production and the supply of glycolytic intermediates to maintain synthetic processes. The results of this investigation will also have significance in the clinical interpretation of M2-PK concentrations.

Gene expression analysis of ischemic and nonischemic cardiomyopathy: shared and distinct genes in the development of heart failure

Cardiomyopathy can be initiated by many factors, but the pathways from unique inciting mechanisms to the common end point of ventricular dilation and reduced cardiac output are unclear. We previously described a microarray-based prediction algorithm differentiating nonischemic (NICM) from ischemic cardiomyopathy (ICM) using nearest shrunken centroids. Accordingly, we tested the hypothesis that NICM and ICM would have both shared and distinct differentially expressed genes relative to normal hearts and compared gene expression of 21 NICM and 10 ICM samples with that of 6 nonfailing (NF) hearts using Affymetrix U133A GeneChips and significance analysis of microarrays. Compared with NF, 257 genes were differentially expressed in NICM and 72 genes in ICM. Only 41 genes were shared between the two comparisons, mainly involved in cell growth and signal transduction. Those uniquely expressed in NICM were frequently involved in metabolism, and those in ICM more often had catalytic activity. Novel genes included angiotensin-converting enzyme-2 (ACE2), which was upregulated in NICM but not ICM, suggesting that ACE2 may offer differential therapeutic efficacy in NICM and ICM. In addition, a tumor necrosis factor receptor was downregulated in both NICM and ICM, demonstrating the different signaling pathways involved in heart failure pathophysiology. These results offer novel insight into unique disease-specific gene expression that exists between end-stage cardiomyopathy of different etiologies. This analysis demonstrates that transcriptome analysis offers insight into pathogenesis-based therapies in heart failure management and complements studies using expression-based profiling to diagnose heart failure of different etiologies.

Small guanine nucleotide-binding protein Rho and myocardial function

RhoA and Rho-kinase (ROCK) participate in a wide variety of cell signal functions such as cell growth, smooth and cardiac muscle contraction, cytoskeleton rearrangement, cell migration and proliferation. In vascular smooth muscle cells, RhoA and ROCK play an important role in Ca2+ sensitization and regulate vascular smooth muscle tone. In the heart, RhoA and ROCK mediate hypertrophic response leading to cardiac hypertrophy. Recent cellular and molecular biology studies using ROCK inhibitors such as Y-27632 and fasudil have indicated a pivotal role of the RhoA-ROCK cascade in many aspects of cardiovascular function such as cardiac hypertrophy and ventricular remodeling following myocardial infarction. Inhibition of the RhoA-ROCK signaling pathway may be a suitable target for a number of cardiovascular diseases including hypertension, atherosclerosis, diabetes and hypertrophic heart failure. This review focuses on the current understanding of the RhoA-ROCK signal pathway in heart diseases and discusses the use of ROCK inhibitors as therapeutic agents for heart diseases ranging from hypertensive cardiomyopathy to heart failure.

Expression of phospholipase D isozymes in scar and viable tissue in congestive heart failure due to myocardial infarction

The phospholipase D (PLD) associated with the cardiac sarcolemmal (SL) membrane hydrolyses phosphatidylcholine to produce phosphatidic acid, an important phospholipid signaling molecule known to influence cardiac function. The present study was undertaken to examine PLD isozyme mRNA expression, protein contents and activities in congestive heart failure (CHF) subsequent to myocardial infarction (MI). MI was induced in rats by occlusion of the left anterior descending coronary artery. At 8 weeks after the surgical procedure, hemodynamic assessment revealed that these experimental rats were at a moderate stage of CHF. Semi-quantitative reverse transcriptase-polymerase chain reaction revealed that PLD1 and PLD2 mRNA amounts were unchanged in viable left ventricular (LV) tissue of the failing heart. Furthermore, this technique demonstrated the presence of PLD1 and PLD2 mRNA in the scar tissue. While SL PLD1 and PLD2 protein contents were elevated in the viable LV tissue of the failing heart, SL PLD1 activity was significantly decreased, whereas SL PLD2 activity was significantly increased. On the other hand, although PLD1 protein was undetectable, PLD2 protein and activity were detected in the scar tissue. Our findings suggest that differential changes in PLD isozymes may contribute to the pathophysiology of CHF and may also be involved in the processes of scar remodeling.

[Cyclic GMP as a biomarker for cardiovascular disease and cancer]

BACKGROUND

Levels of cyclic guanosine 3',5'-monophosphate (cGMP) are elevated in plasma and urine from patients with some cardiovascular diseases and some types of cancer.

MATERIALS AND METHODS

This paper is based on studies of cGMP as a biomarker.

RESULTS AND INTERPRETATION

It is well documented that cGMP levels are elevated in plasma in patients with heart failure and various leukaemias and in urine from patients with gynaecological cancers. Because of great interindividual variation in levels, cGMP is less suitable in primary diagnostics, but appears to be a sensitive marker in individual follow up in some diseases.

Proinflammatory cytokines, soluble Fas receptor, nitric oxide and angiotensin converting enzyme in congestive heart failure

We measured serum interleukin-2 receptor (sIL-2R), tumor necrosis factor-a (TNF-a), Fas receptor (sFas), nitric oxide (NO), and angiotensin converting enzyme (ACE) activity in 45 patients with congestive heart failure (CHF) of different etiologies. The relatioship between these bioindices and the severity of heart failure was analysed. Patients were classified according to the etiology of heart failure into: 15 patients with rheumatic valvular heart disease (RHD), 17 with ischemic heart disease (IHD) and 13 with idiopathic dilated cardiomyopathy (DCM). Patients were further classified according to severity of CHF following the New York Heart Association classification (NYHA) into: NYHA class II (n= 7), NYHA class III (n=20) and NYHA class IV (n=18). Eighteen healthy subjects were included as controls. Serum sIL-2R, TNF-alpha and sFas levels were determined by ELISA while serum NO and ACE levels were measured by colorimetric methods. Doppler Echocardiography was performed for all participants. Levels of sIL-2R, TNF-alpha, sFas, NO, and ACE were significantly higher in CHF patients than controls. Levels of the bioindices varied according to the CHF etiology. TNF-a level was the only one that had significant differences among different subgroups (RHD, IHD and DCM). The levels of sIL-2R, TNF-alpha, NO and sFas in patients with NYHA class IV were significantly higher than class II or III. Moreover, sIL-2R, TNF-alpha and NO levels were significantly higher in patients with diastolic dysfunction than patients with normal diastolic function. A significant positive correlations were found between sFas and both TNF-alpha and sIL-2R and between TNF-alpha and both NO and diastolic function. In addition, significant positive correlations were found between TNF-alpha and sIL-2R in both IHD and RHD patients and between sIL-2R and both ACE in IHD patients and diastolic function in DCM patients. It is concluded that a relationship exists between immune system activation, apoptosis and renin- angiotensin system in CHF and this may play a significant role in the pathophysiology and prognosis of the disease.

Protein Kinase C in Cardiac Disease and as a Potential Therapeutic Target

Protein kinase C (PKC) is a member of a large family of serine/threonine kinases that plays an integral role in many of the signaling cascades that govern cellular behavior. As such, it is intricately involved in the processes that mediate disease pathogenesis. Strategies that serve to alter PKC function may prove to be useful in the treatment of numerous disease states. This article reviews the various roles PKC may play in cardiovascular disease, specifically with regard to ischemic heart disease, cardiac hypertrophy, heart failure, hypertension, and atherosclerosis, and suggests the potential for developing therapeutic approaches that can target PKC activity.

Deficiency of iNOS does not attenuate severe congestive heart failure in mice

Inducible nitric oxide synthase (iNOS) has been implicated in the pathophysiology of congestive heart failure (CHF). Given the extensive evidence supporting this concept, we hypothesized that iNOS deficiency (iNOS−/−) would attenuate the severity of CHF in mice. Mice were subjected to permanent occlusion [myocardial infarction (MI)] of the proximal left anterior descending coronary artery to produce CHF. Cardiac function was assessed in vivo using echocardiography and ultraminiature ventricular pressure catheters. Sham wild-type ( n = 17), sham iNOS−/− ( n = 8), MI wild-type ( n = 56), and MI iNOS−/− ( n = 48) mice were subjected to MI (or sham MI) and followed for 1 mo. Deficiency of iNOS did not alter survival during CHF compared with wild type (35% vs. 32%, P = not significant). Furthermore, fractional shortening and cardiac output were not significantly different between wild-type (9.6 ± 2.0% and 441 ± 20 μl·min−1·g−1) and iNOS−/− (9.8 ± 1.3% and 471 ± 26 μl·min−1·g−1) mice. The extent of cardiac hypertrophy and pulmonary edema was also similar between wild-type and iNOS−/− mice. None of the indexes demonstrated any significant differences between iNOS−/− and wild-type mice subjected to MI. These findings indicate that deficiency of iNOS does not significantly affect severe CHF in mice after MI.

Neurohormonal activation is associated with increased levels of plasma matrix metalloproteinase-2 in human heart failure

AIMS

Development of heart failure depends on systemic and molecular abnormalities among which are the activation of neurohormonal systems and the increase of matrix metalloproteinases (MMPs). This study assessed the relationship between catecholamines and active MMPs in vivo in patients with severe congestive heart failure (CHF) and in vitro in human cardiac fibroblasts.

METHODS AND RESULTS

Forty patients with CHF due to dilated cardiomyopathy, either idiopathic (n=20) or secondary to ischaemic heart disease (n=20), were compared with 20 healthy subjects. Plasma MMP-2 and MMP-9 activity, but not TIMP-2, were significantly higher in patients than in controls (median MMP-2, 270 vs. 214 ng/mL, P=0.006; MMP-9 16.3 vs. 8.7 ng/mL, P<0.0001). Similarly, noradrenaline, but not adrenaline, was significantly higher in patients (noradrenaline 645 vs. 157 pg/mL, P<0.0001; adrenaline 86.0 vs. 72.6 pg/mL, P=0.68). No difference in any parameter was observed between patient groups. The intra-group correlation between MMP-2 and noradrenaline was significant (r=0.33, P=0.01); indeed, noradrenaline appear to be a predictor of MMP-2. Moreover, this catecholamine increased MMP-2 in human cardiac fibroblasts.

CONCLUSIONS

The positive correlation between noradrenaline and MMP-2 in severe CHF patients, together with the in vitro induction of MMP-2 by this catecholamine, suggests a potential biochemical link between noradrenaline and MMP-2.

Statin therapy for cardiac hypertrophy and heart failure

Cardiac hypertrophy leading to heart failure is a major cause of morbidity and mortality worldwide. The 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors, or statins, have been shown to inhibit cardiac hypertrophy and improve symptoms of heart failure by cholesterol-independent mechanisms. Statins block the isoprenylation and function of members of the Rho guanosine triphosphatase family, such as Rac1 and RhoA. Because Rac1 is a requisite component of reduced nicotinamide adenine dinucleotide phosphate oxidase, which is a major source of reactive oxygen species in cardiovascular cells, the ability of statins to inhibit Rac1-mediated oxidative stress contributes importantly to their inhibitory effects on cardiac hypertrophy. Furthermore, inhibition of RhoA by statins leads to the activation of protein kinase B/Akt and up-regulation of endothelial nitric oxide synthase in the endothelium and the heart. This results in increased angiogenesis and myocardial perfusion, decreased myocardial apoptosis, and improvement in endothelial and cardiac function. Because these effects of statins occur independently of cholesterol lowering, statins may have therapeutic benefits in nonhyperlipidemic patients with cardiac hypertrophy and heart failure.