Impact of Sirolimus as a Primary Immunosuppressant on Myocardial Fibrosis and Diastolic Function Following Heart Transplantation.

Background Myocardial fibrosis is an important contributor for development of diastolic dysfunction. We investigated the impact of sirolimus as primary immunosuppression on diastolic dysfunction and fibrosis progression among heart transplantation recipients. Methods and Results In 100 heart transplantation recipients who were either treated with a calcineurin inhibitor (CNI) (n=51) or converted from CNI to sirolimus (n=49), diastolic function parameters were assessed using serial echocardiograms and right heart catheterizations. Myocardial fibrosis was quantified on serial myocardial biopsies. After 3 years, lateral e' increased within the sirolimus group but decreased in the CNI group (0.02±0.04 versus -0.02±0.04 m/s delta change; P=0.003, respectively). Both pulmonary capillary wedge pressure and diastolic pulmonary artery pressure significantly decreased in the sirolimus group but remained unchanged in the CNI group (-1.50±2.59 versus 0.20±2.20 mm Hg/year; P=0.02; and -1.72±3.39 versus 0.82±2.59 mm Hg/year; P=0.005, respectively). A trend for increased percentage of fibrosis was seen in the sirolimus group (8.48±3.17 to 10.10±3.0%; P=0.07) as compared with marginally significant progression in the CNI group (8.76±3.87 to 10.56±4.34%; P=0.04). The percent change in fibrosis did not differ significantly between the groups (1.62±4.67 versus 1.80±5.31%, respectively; P=0.88). Conclusions Early conversion to sirolimus is associated with improvement in diastolic dysfunction and filling pressures as compared with CNI therapy. Whether this could be attributed to attenuation of myocardial fibrosis progression with sirolimus treatment warrants further investigation.

Menopause-Related Estrogen Decrease and the Pathogenesis of HFpEF: JACC Review Topic of the Week.

Heart failure (HF) is a complex condition affecting >40 million people worldwide. It is defined by failure of the heart to pump (HF with reduced ejection fraction) or by the failure of the heart to relax, resulting in reduced filling but with preserved ejection fraction (HFpEF). HFpEF affects approximately 50% of patients with HF, most of whom are women. Given that the annual mortality ranges from 10% to 30% and as there are no treatments specifically directed for HFpEF, there is a need for better understanding of the underlying mechanisms of this condition. We put forward the hypothesis that the decline of estrogen at menopause might contribute to the pathogenesis of HFpEF and we highlight potential underlying mechanisms of estrogen action, which may attenuate the development of HFpEF. We also discuss areas in which additional research is needed to develop new approaches for prevention and treatment of HFpEF.

Urinary Peptidomic Biomarker for Personalized Prevention and Treatment of Diastolic Left Ventricular Dysfunction.

Diastolic heart failure (DHF) is characterized by slow left ventricular (LV) relaxation, increased LV stiffness, interstitial deposition of collagen, and a modified extracellular matrix proteins. Among Europeans, the frequency of asymptomatic diastolic LV dysfunction (DD) is 25%. This constitutes a large pool of people at high risk of DHF. The goal of this review was to describe the discovery and the initial validation of new multidimensional urinary peptidomic biomarkers (UPB) indicative of DD, mainly consisting of collagen fragments, and to describe a roadmap for their introduction into clinical practice. The availability of new drugs creates a window of opportunity for mounting a randomized clinical trial consolidating the clinical applicability of UPB to screen for DD. If successfully completed, such trial will benefit ≈25% of all people older than 50 years and open a large market for a UPB diagnostic tool and the drug tested. Moreover, sequenced peptides making up UPB will generate novel insights in the pathophysiology of DD and facilitate personalized treatment of patients with DHF for whom prevention came too late. If proven cost-effective, the clinical application of UPB will contribute to the sustainability of health care in aging population in epidemiologic transition.

Heart Failure with Preserved Ejection Fraction: Diagnosis and Management.

Heart failure with preserved ejection fraction, also referred to as diastolic heart failure, causes almost one-half of the 5 million cases of heart failure in the United States. It is more common among older patients and women, and results from abnormalities of active ventricular relaxation and passive ventricular compliance, leading to a decline in stroke volume and cardiac output. Heart failure with preserved ejection fraction should be suspected in patients with typical symptoms (e.g., fatigue, weakness, dyspnea, orthopnea, paroxysmal nocturnal dyspnea, edema) and signs (S3 heart sound, displaced apical pulse, and jugular venous distension) of chronic heart failure. Echocardiographic findings of normal ejection fraction with impaired diastolic function confirm the diagnosis. Measurement of natriuretic peptides is useful in the evaluation of patients with suspected heart failure with preserved ejection fraction in the ambulatory setting. Multiple trials have not found medications to be an effective treatment, except for diuretics. Patients with congestive symptoms should be treated with a diuretic. If hypertension is present, it should be treated according to evidence-based guidelines. Exercise and treatment by multidisciplinary teams may be helpful. Atrial fibrillation should be treated using a rate-control strategy and appropriate anticoagulation. Revascularization should be considered for patients with heart failure with preserved ejection fraction and coronary artery disease. The prognosis is comparable to that of heart failure with reduced ejection fraction and is worsened by higher levels of brain natriuretic peptide, older age, a history of myocardial infarction, and reduced diastolic function.

Inhibition of the Cardiac Fibroblast-Enriched lncRNA Meg3 Prevents Cardiac Fibrosis and Diastolic Dysfunction.

RATIONALE: Cardiac fibroblasts (CFs) drive extracellular matrix remodeling after pressure overload, leading to fibrosis and diastolic dysfunction. Recent studies described the role of long noncoding RNAs (lncRNAs) in cardiac pathologies. Nevertheless, detailed reports on lncRNAs regulating CF biology and describing their implication in cardiac remodeling are still missing. OBJECTIVE: Here, we aimed at characterizing lncRNA expression in murine CFs after chronic pressure overload to identify CF-enriched lncRNAs and investigate their function and contribution to cardiac fibrosis and diastolic dysfunction. METHODS AND RESULTS: Global lncRNA profiling identified several dysregulated transcripts. Among them, the lncRNA maternally expressed gene 3 (Meg3) was found to be mostly expressed by CFs and to undergo transcriptional downregulation during late cardiac remodeling. In vitro, Meg3 regulated the production of matrix metalloproteinase-2 (MMP-2). GapmeR-mediated silencing of Meg3 in CFs resulted in the downregulation of Mmp-2 transcription, which, in turn, was dependent on P53 activity both in the absence and in the presence of transforming growth factor-ß I. Chromatin immunoprecipitation showed that further induction of Mmp-2 expression by transforming growth factor-ß I was blocked by Meg3 silencing through the inhibition of P53 binding on the Mmp-2 promoter. Consistently, inhibition of Meg3 in vivo after transverse aortic constriction prevented cardiac MMP-2 induction, leading to decreased cardiac fibrosis and improved diastolic performance. CONCLUSIONS: Collectively, our findings uncover a critical role for Meg3 in the regulation of MMP-2 production by CFs in vitro and in vivo, identifying a new player in the development of cardiac fibrosis and potential new target for the prevention of cardiac remodeling.

The Effect of Exercise Training on Diastolic and Systolic Function After Acute Myocardial Infarction: A Randomized Study.

After acute myocardial infarction (AMI), diastolic dysfunction is frequent and an important determinant of adverse outcome. However, few interventions have proven to be effective in improving diastolic function. We aimed to determine the effect of exercise training on diastolic and systolic function after AMI.One month after AMI, 188 patients were prospectively randomized (1:1) to an 8-week supervised program of endurance and resistance exercise training (n = 86; 55.9 ±â€Š10.8 years) versus standard of care (n = 89; 55.4 ±â€Š10.3 years). All patients were submitted to detailed echocardiography and cardiopulmonary exercise test, at baseline and immediately after the study. Diastolic function was evaluated by the determination of tissue-Doppler derived early diastolic velocities (E' velocity at the septal and lateral sides of mitral annulus) and by the E/E' (ratio between the E wave velocity from mitral inflow and the E' velocity) as recommended in the consensus document for diastolic function assessment.At the end of the study, there was no significant change in E' septal velocity or E/E' septal ratio in the exercise group. We observed a small, although nonsignificant, improvement in E' lateral (mean change 0.1 ±â€Š2.0 cm/s; P = 0.40) and E/E' lateral ratio (mean change of -0.3 ±â€Š2.5; P = 0.24), while patients in the control group had a nonsignificant reduction in E' lateral (mean change -0.4 ±â€Š1.9 cm/s; P = 0.09) and an increase in E/E' lateral ratio (mean change + 0.3 ±â€Š3.3; P = 0.34). No relevant changes occurred in other diastolic parameters. The exercise-training program also did not improve systolic function (either tissue Doppler systolic velocities or ejection fraction).Exercise capacity improved only in the exercise-training group, with an increase of 1.6 mL/kg/min in pVO2 (P = 0.001) and of 1.9 mL/kg/min in VO2 at anaerobic threshold (P < 0.001).After AMI, an 8-week endurance plus resistance exercise-training program did not significantly improve diastolic or systolic function, although it was associated with an improvement in exercise capacity parameters.

Beneficial effects of angiotensin-(1-7) against deoxycorticosterone acetate-induced diastolic dysfunction occur independently of changes in blood pressure.

Mineralocorticoids have been implicated in the pathogenesis of diastolic heart failure. On the contrary, angiotensin (Ang)-(1-7) has emerged as a potential strategy for treatment of cardiac dysfunction induced by excessive mineralocorticoid receptor activation. A critical question about the cardioprotective effect of Ang-(1-7) in hypertensive models is its dependence on blood pressure (BP) reduction. Here, we addressed this question by investigating the mechanisms involved in Ang-(1-7) cardioprotection against mineralocorticoid receptor activation. Sprague-Dawley (SD) and transgenic (TG) rats that overexpress an Ang-(1-7) producing fusion protein (TG(A1-7)3292) were treated with deoxycorticosterone acetate (DOCA) for 6 weeks. After treatment, SD rats became hypertensive and developed ventricular hypertrophy. These parameters were attenuated in TG-DOCA. SD-DOCA rats developed diastolic dysfunction which was associated at the cellular level with reduced Ca(2+) transient. Oppositely, TG-DOCA myocytes presented enhanced Ca(2+) transient. Moreover, higher extracellular signal-regulated kinase phosphorylation, type 1 phosphatase, and protein kinase Cα levels were found in SD-DOCA cells. In vivo, pressor effects of DOCA can contribute to the diastolic dysfunction, raising the question of whether protection in TG was a consequence of reduced BP. To address this issue, BP in SD-DOCA was kept at TG-DOCA level by giving hydralazine or by reducing the DOCA amount given to rats (Low-DOCA). Under similar BP, diastolic dysfunction and molecular changes were still evident in DOCA-hydralazine and SD-low-DOCA, but not in TG-DOCA. In conclusion, Ang-(1-7) protective signaling against DOCA-induced diastolic dysfunction occurs independently of BP attenuation and is mediated by the activation of pathways involved in Ca(2+) handling, hypertrophy, and survival.

Optimising exercise training in prevention and treatment of diastolic heart failure (OptimEx-CLIN): rationale and design of a prospective, randomised, controlled trial.

BACKGROUND: Heart failure with preserved left ventricular ejection fraction (HFpEF) currently affects more than seven million Europeans and is the only cardiovascular disease increasing in prevalence and incidence. No pharmacological agent has yet been shown to improve symptoms or prognosis. The most promising way to improve pathophysiology and deprived exercise-tolerance in HFpEF patients seems to be exercise training, but the optimal approach and dose of exercise is still unknown. OBJECTIVES: The major objective of the optimising exercise training in prevention and treatment of diastolic heart failure study (OptimEx-CLIN) is to define the optimal dose of exercise training in patients with HFpEF. In order to optimise adherence, supervision and economic aspects of exercise training a novel telemedical approach will be introduced and investigated. STUDY DESIGN: In a prospective randomised multi-centre study, 180 patients with stable symptomatic HFpEF will be randomised (1:1:1) to moderate intensity continuous training, high intensity interval training, or a control group. The training intervention includes three months supervised followed by nine months of telemedically monitored home-based training. The primary endpoint is change in exercise capacity, defined as change in peak oxygen uptake (VO2peak) after three months, assessed by cardiopulmonary exercise testing. Secondary endpoints include diastolic filling pressure (E/e') and further echocardiographic and cardiopulmonary exercise testing (CPX) parameters, biomarkers, quality of life and endothelial function. Training sessions and physical activity will be monitored and documented throughout the study with accelerometers and heart rate monitors developed on a telemedical platform for the OptimEx-CLIN study. Inclusion of patients started in July 2014, first results are expected in 2017.

Disfunción cardiaca en la cirrosis hepática / Cardiac dysfunction in liver cirrhosis

Objetivo: determinar las alteraciones de la función cardiaca en las personas que padecen cirrosis hepática. Métodos: se desarrolló un estudio descriptivo transversal en el Instituto de Gastroenterología durante el período 2011-2012, en 33 cirróticos de causa viral y alcohólica, 57,6 por ciento del sexo masculino, con una edad promedio de 50 años, la mayoría (84,8 por ciento) tenía la enfermedad compensada. Resultados: la disfunción diastólica fue la alteración cardiaca más frecuente (39,3 por ciento) seguida de la prolongación del intervalo QT (12,1 por ciento), disfunción sistólica (6,1 por ciento) y miocardiopatía cirrótica (3 por ciento). No se identificaron rasgos distintivos epidemiológicos y/o clínicos que caracterizara a estos pacientes. La circulación hiperdinámica fue más evidente en los que presentaron disfunción diastólica y en la cirrosis de origen alcohólico; las dimensiones cardiacas fueron normales en todos los casos. Conclusiones: las personas que padecen cirrosis son susceptibles de presentar alteraciones de la función cardiaca, incluso, desde la etapa compensada de la enfermedad, lo que debe considerarse por las implicaciones terapéuticas que demanda este tipo de paciente...

Objective: to determine abnormalities of cardiac function in subjects with liver cirrhosis. Methods: a descriptive cross-sectional study was conducted at the Institute of Gastroenterology from 2011 to 2012, in 33 cirrhotic patients due to alcoholic and viral causes, 57.6 percent male, with an average age of 50 years, most (84,8 percent) had compensated disease. Results: diastolic dysfunction was the most common cardiac disorders (39.3 percent) followed by QT prolongation (12.1 percent), systolic dysfunction (6.1 percent) and cirrhotic (3 percent) cardiomyopathy interval. No distinctive epidemiological and/or clinical studies were identified to characterize these patients. The hyperdynamic circulation was more evident in those presenting diastolic dysfunction and alcohol-related cirrhosis. Cardiac dimensions were normal in all cases. Conclusions: people with cirrhosis are susceptible to alterations in cardiac function, even from the compensated stage of the disease, which should be considered by the therapeutic implications of this type of patient demand...

Diastolic ventricular support with cardiac support devices: an alternative approach to prevent adverse ventricular remodeling.

Heart failure is a global epidemic with limited therapy. Abnormal left ventricular wall stress in the diseased myocardium results in a biochemical positive feedback loop that results in global ventricular remodeling and further deterioration of myocardial function. Mechanical myocardial restraints such as the Acorn CorCap and Paracor HeartNet ventricular restraints have attempted to minimize diastolic ventricular wall stress and limit adverse ventricular remodeling. Unfortunately, these therapies have not yielded viable clinical therapies for heart failure. Cellular and novel biopolymer-based therapies aimed at stabilizing pathologic myocardium hold promise for translation to clinical therapy in the future.

Efecto agudo hipotensivo de la combinación de ejercicios basados en caminar y de resistencia en mujeres mayores de 65 años no institucionalizadas / Hypotensive acute effect of a combined resistance and walk-based exercise among over 65-year old community-dwelling women

Objective. The aim of this study was to test the effects on blood pressure of a single bout of low-intensity resistance exercise combined with moderate aerobic walk-based exercise performed by active, controlled hypertensive elderly women. Method. Forty-two participants were randomized in two types of sessions: exercise session (n = 21), that performed a single bout of combined exercise and control session (n = 21) that keep in rest during the bout. Pre-session, post-session and post-24-hour systolic, diastolic and mean pressure values were evaluated and compared between groups. Results. Statistical significant reductions were achieved just after the performed bout (7% of reduction) and 24 hours after the bout (9% of reduction) on the diastolic blood pressure values in the exercise session group. Conclusions. In this population, a single bout of combined session is feasible and safe and has a hypotensive effect on diastolic blood pressure in both immediately and after 24 hours post exercise(AU)

Objetivo. Comprobar el efecto hipotensivo que una sola sesión de ejercicio combinado puede tener sobre la presión arterial de mujeres hipertensas controladas y mayores de 65 años. Método. Cuarenta y dos participantes fueron asignadas aleatoriamente a dos grupos de sesiones: sesión de entrenamiento (n = 21) que realizó una sola sesión de ejercicios combinados y sesión control (n = 21) que mantuvo reposo durante la misma. Antes, después y tras 24 horas desde la sesión, los valores de presión sistólica, diastólica y medios fueron evaluados y comparados entre grupos. Resultados. Se encontraron diferencias estadísticamente significativas entre los grupos tras la realización de la sesión (7% de reducción) y tras 24 horas (9% de reducción) en los valores de presión arterial diastólica media del grupo experimental. Conclusiones. En esta población una sola sesión de ejercicio combinado se propone como aplicable y segura y tiene un efecto hipotensivo en la presión diastólica tanto inmediatamente después como pasadas 24 horas de la intervención(AU)

Diastolic heart failure and LV dyssynchrony.

Our knowledge of diastolic heart failure (DHF) is still limited with regard to pathophysiology, diagnosis and clinical treatment. Amongst others, LV dyssynchrony was suggested to be an additional factor involved in the pathogenesis of subgroup of patients with DHF. In 20-30% of patients with DHF a systolic LV dyssynchrony could be detected and about 20% DHF patients evidenced a diastolic dyssyncrony. Both systolic and diastolic dyssynchrony may contribute to the impairment of cardiac function and clinical manifestation in DHF. Opposite to the systolic heart failure, wide QRS complex is uncommon which incriminates that dyssynchrony in DHF is rather related to regional disperse in contractility than to electromechanical coupling delay. Asynchronous LV relaxation and impairment of ventricular restoring forces may also impair the LV filing and lead to a diastolic dyssynchrony. Particularly in patients with preserved LV contractility mechanical LV dyssynchrony induces energy wastage and consequently reduces cardiac reserves. However, up to date it is not clear to what degree LV dyssynchrony is involved in the pathomechanisms of this subpopulation of DHF.

Allopurinol attenuates oxidative stress and cardiac fibrosis in angiotensin II-induced cardiac diastolic dysfunction.

AIMS: Oxidative stress and fibrosis is implicated in cardiac remodeling and failure. We tested whether allopurinol could decrease myocardial oxidative stress and attenuate cardiac fibrosis and left ventricular diastolic dysfunction in angiotensin II (AngII)-induced hypertensive mice. METHODOLOGY: We used 8-week-old male C57BL/6J mice, in which angiotensin II was subcutaneously infused for 4 weeks to mimic cardiac remodeling and fibrosis. They were treated with either normal saline or allopurinol in daily doses, which did not lower blood pressure. RESULTS: Allopurinol improved diastolic dysfunction in angiotensin II-induced hypertensive mice, which was associated with the amelioration of cardiac fibrosis. However, allopurinol showed no effect on the increased systolic blood pressure by angiotensin II infusion. The ratio of reduced glutathione (GSH) to oxidized glutathione (GSSG) [GSH/GSSG] was decreased and malondialdehyde levels were increased in the hearts of AngII-treated mice. Allopurinol also inhibited both the decrease in the GSH/GSSG ratio and the increase in malondialdehyde levels in the heart. Infusion of AngII-induced upregulation of transfer growth factor (TGF)-ß1, Smad3 expression and downregulation of Smad7 expression. Treatment with allopurinol reduced cardiac levels of TGF-ß1, Smad3, and increased Smad7 expression. CONCLUSIONS: These results suggest that allopurinol prevents pathological remodeling of the heart in AngII-induced hypertensive mice. The antioxidative effect of allopurinol contributes to the regression of AngII-induced cardiac diastolic dysfunction. These effects of allopurinol to prevent cardiac fibrosis are mediated at least partly through modulation of the TGF-ß1/Smad signaling pathway.

Diastolic heart failure: progress, treatment challenges, and prevention.

Diastolic heart failure (DHF) is an important entity, the significance of which is increasingly recognized. This report examines the available evidence regarding the role, significance, and mechanisms of DHF. Epidemiologic studies have documented the rising burden of DHF, and experimental data are revealing the unique mechanisms distinguishing it from systolic heart failure. Despite controversies on the definition of DHF, or heart failure with preserved ejection fraction, standardized clinical criteria with supplementary imaging and structural data have identified DHF as a distinct pathophysiological entity. The mechanisms underlying DHF include abnormal matrix dynamics, altered myocyte cytoskeleton, and impaired active relaxation. The commonly held belief that survival of patients with DHF is better than that of patients with systolic heart failure has been challenged by updated data. The heterogeneous etiologies or risk factors for the condition include aging, diabetes, hypertension, and ischemia, making a common diagnostic or treatment pathway difficult. Novel therapeutic targets that address the pathophysiology of this disease are under consideration, although there are no proven therapies for DHF to date. Exacerbating factors include volume and sodium indiscretion, arrhythmias, ischemia, and comorbidities. Strategies to ameliorate or to obviate these precipitating factors are most effective in preventing DHF and its exacerbations. Meanwhile, prevention of DHF through appropriate and aggressive risk factor identification and management must remain the cornerstone of clinical intervention.

Evaluating the effectiveness of rosuvastatin in preventing the progression of diastolic dysfunction in aortic stenosis: A substudy of the aortic stenosis progression observation measuring effects of rosuvastatin (ASTRONOMER) study.

BACKGROUND: Tissue Doppler imaging (TDI) is a noninvasive echocardiographic method for the diagnosis of diastolic dysfunction in patients with varying degrees of aortic stenosis (AS). Little is known however, on the utility of TDI in the serial assessment of diastolic abnormalities in AS. OBJECTIVE: The aim of the current proposal was to examine whether treatment with rosuvastatin was successful in improving diastolic abnormalities in patients enrolled in the Aortic Stenosis Progression Observation Measuring Effects of Rosuvastatin (ASTRONOMER) study. METHODS: Conventional Doppler indices including peak early (E) and late (A) transmitral velocities, and E/A ratio were measured from spectral Doppler. Tissue Doppler measurements including early (E') and late (A') velocities of the lateral annulus were determined, and E/E' was calculated. RESULTS: The study population included 168 patients (56 ± 13 years), whose AS severity was categorized based on peak velocity at baseline (Group I: 2.5-3.0 m/s; Group II: 3.1-3.5 m/s; Group III: 3.6-4.0 m/s). Baseline and follow-up hemodynamics, LV dimensions and diastolic functional parameters were evaluated in all three groups. There was increased diastolic dysfunction from baseline to follow-up in each of the placebo and rosuvastatin groups. In patients with increasing severity of AS in Groups I and II, the lateral E' was lower and the E/E' (as an estimate of increased left ventricular end-diastolic pressure) was higher at baseline (p < 0.05). However, treatment with rosuvastatin did not affect the progression of diastolic dysfunction from baseline to 3.5 year follow-up between patients in any of the three predefined groups. CONCLUSION: In patients with mild to moderate asymptomatic AS, rosuvastatin did not attenuate the progression of diastolic dysfunction.

Neuronal nitric oxide synthase inhibition improves diastolic function and reduces oxidative stress in ovariectomized mRen2.Lewis rats.

OBJECTIVE: The loss of estrogen in mRen2.Lewis rats leads to an exacerbation of diastolic dysfunction. Because specific neuronal nitric oxide synthase (nNOS) inhibition reverses renal damage in the same model, we assessed the effects of inhibiting neuronal nitric oxide on diastolic function, left ventricular remodeling, and the components of the cardiac nitric oxide system in ovariectomized (OVX) and sham-operated mRen2.Lewis rats treated with N5-(1-imino-3-butenyl)-L-ornithine (L-VNIO; 0.5 mg/kg per day for 28 d) or vehicle (saline). METHODS: Female mRen2.Lewis rats underwent either bilateral oophorectomy (OVX; n = 15) or sham operation (or surgical procedure) (sham; n = 19) at 4 weeks of age. Beginning at 11 weeks of age, the rats were randomized to receive either L-VNIO or vehicle. RESULTS: The surgical loss of ovarian hormones, particularly estrogen, led to exacerbated hypertension, impaired myocardial relaxation, diminished diastolic compliance, increased perivascular fibrosis, and increased relative wall thickness. The cardiac tetrahydrobiopterin-to-dihydrobiopterin levels were lower among OVX rats compared with sham-operated rats, and this altered cardiac biopterin profile was associated with enhanced myocardial superoxide production and decreased nitric oxide release. L-VNIO decreased myocardial reactive oxygen species production, increased nitrite concentrations, attenuated cardiac remodeling, and improved diastolic function. CONCLUSIONS: Impaired relaxation, diastolic stiffness, and cardiac remodeling were found among OVX mRen2.Lewis rats. A possible mechanism for this unfavorable cardiac phenotype may have resulted from a deficiency in available tetrahydrobiopterin and subsequent increase in nNOS-derived superoxide and reduction in nitric oxide synthase metabolites within the heart. Selective nNOS inhibition with L-VNIO attenuated cardiac superoxide production and limited remodeling, leading to improved diastolic function in OVX mRen2.Lewis rats.

Vascular endothelial growth factor-B gene transfer prevents angiotensin II-induced diastolic dysfunction via proliferation and capillary dilatation in rats.

AIMS: heart growth and function are angiogenesis-dependent, but little is known concerning the effects of key regulators of angiogenesis on diastolic heart failure. Here, we tested the hypothesis that local vascular endothelial growth factor-B (VEGF-B) gene therapy prevents left ventricular diastolic dysfunction. METHODS AND RESULTS: rats were subjected to pressure overload by infusing angiotensin II (33.3 microg/kg/h) for 2 weeks using osmotic minipumps. Intramyocardial delivery of adenoviral vector expressing VEGF-B(167A) improved the angiotensin II-induced diastolic dysfunction compared with LacZ control virus. Local VEGF-B gene transfer increased the mean capillary area in the left ventricle in control and angiotensin II-infused animals, whereas the density of capillaries was not affected. Interestingly, significant increases were noted in Ki67(+) proliferating cells, expression of interleukin1ß, and c-kit(+) cells in response to VEGF-B gene transfer. The increase in cardiac c-kit(+) cells was not associated with an induction of stromal cell-derived factor 1α, suggesting no mobilization of cells from bone marrow. Also, the phosphatidylinositol 3-kinase/Akt pathway was activated. CONCLUSION: VEGF-B gene transfer resulted in prevention of the angiotensin II-induced diastolic dysfunction associated with induction of the Akt pathway, increased proliferation and number of c-kit(+) cells, as well as an increase in the capillary area in the left ventricle. VEGF-B may offer novel therapeutic possibilities for the prevention of the transition from compensated to decompensated cardiac hypertrophy and thereby for the treatment of heart failure.

Whole grape intake impacts cardiac peroxisome proliferator-activated receptor and nuclear factor kappaB activity and cytokine expression in rats with diastolic dysfunction.

Prolonged hypertension is the leading cause of heart failure. Failing hearts show reduced peroxisome proliferator-activating receptor (PPAR) activity and enhanced nuclear factor kappaB (NF-kappaB) activity, which together modify cardiac inflammation and fibrosis. In vitro studies suggest that phytochemicals alter PPAR and NF-kappaB activity, but the capabilities of a phytochemical-rich diet are less understood. Grapes contain an array of commonly consumed dietary phytochemicals. In Dahl salt-sensitive hypertensive rats, we showed previously that dietary provision of whole table grape powder (3% weight:weight) for 18 weeks reduced blood pressure, cardiac hypertrophy, and diastolic dysfunction. The hypothesis tested here is that, in this model, phytochemical provision from whole grape powder impacts cardiac PPAR and NF-kappaB activity and their related gene transcripts. Grape-fed rats had enhanced PPAR-alpha and PPAR-gamma DNA binding activity but reduced NF-kappaB DNA binding activity. RT-PCR revealed that grape-fed rats showed upregulated mRNA for PPAR-alpha, PPAR-gamma coactivator-1alpha, PPAR-gamma, and the cytosolic NF-kappaB inhibitor, inhibitor-kappaBalpha. By contrast, grape-fed rats showed downregulated mRNA for tumor necrosis factor-alpha and transforming growth factor-beta1. Finally, grape-fed rats showed significantly reduced cardiac tumor necrosis factor-alpha and transforming growth factor-beta protein expression, increased inhibitor-kappaBalpha expression, and reduced cardiac fibrosis. In the Dahl salt-sensitive rat, chronic intake of grapes altered cardiac transcripts related to PPAR and NF-kappaB that may be significant to the observed diet-associated cardioprotection.