scholarly journals Seipin Deficiency Accelerates Heart Failure Due to Calcium Handling Abnormalities and Endoplasmic Reticulum Stress in Mice

2021 ◽  
Vol 8 ◽  
Author(s):  
Xiaoyue Wu ◽  
Xuejing Liu ◽  
Huan Wang ◽  
Zihao Zhou ◽  
Chengzhi Yang ◽  
...  
Keyword(s):  
Heart Failure ◽  
Endoplasmic Reticulum ◽  
Cardiac Hypertrophy ◽  
Er Stress ◽  
Diastolic Heart Failure ◽  
Left Ventricular ◽  
Calcium Handling ◽  
Related Factors ◽  
Current Decay ◽  
Protein Levels

Seipin deficiency can induce hypertrophic cardiomyopathy and heart failure, which often leads to death in humans. To explore the effects and the possible mechanisms of Seipin deficiency in myocardial remodeling, Seipin knockout (SKO) mice underwent transverse aortic constriction (TAC) for 12 weeks. We found a more severe left ventricular hypertrophy and diastolic heart failure and increases in inflammatory cell infiltration, collagen deposition, and apoptotic bodies in the SKO group compared to those in the wild type (WT) group after TAC. Electron microscopy also showed a more extensive sarcoplasmic reticulum expansion, deformation of microtubules, and formation of mitochondrial lesions in the cardiomyocytes of SKO mice than in those of WT mice after TAC. Compared with the WT group, the SKO group showed increases in endoplasmic reticulum (ER) stress-, inflammation-, and fibrosis-related gene expression, while calcium ion-related factors, such as Serca2a and Ryr, were decreased in the SKO group after TAC. Increased levels of the ER stress-related protein GRP78 and decreased SERCA2a and P-RYR protein levels were detected in the SKO group compared with the WT group after TAC. Slowing of transient Ca2+ current decay and an increased SR Ca2+ content in myocytes were detected in the cardiomyocytes of SKO mice. Adipose tissue transplantation could not rescue the cardiac hypertrophy after TAC in SKO mice. In conclusion, we found that Seipin deficiency could promote cardiac hypertrophy and diastolic heart failure after TAC in mice. These changes may be related to the impairment of myocardial calcium handling, ER stress, inflammation, and apoptosis.

scholarly journals Interferon-γ ablation exacerbates myocardial hypertrophy in diastolic heart failure

2012 ◽  
Vol 303 (5) ◽  
pp. H587-H596 ◽  
Author(s):  
Anthony G. Garcia ◽  
Richard M. Wilson ◽  
Joline Heo ◽  
Namita R. Murthy ◽  
Simoni Baid ◽  
...  
Keyword(s):  
Heart Failure ◽  
Cardiac Hypertrophy ◽  
Ventricular Myocytes ◽  
Salt Water ◽  
Diastolic Heart Failure ◽  
Velocity Ratio ◽  
Interleukin 10 ◽  
Interferon Γ ◽  
Left Ventricular

Diastolic heart failure (HF) accounts for up to 50% of all HF admissions, with hypertension being the major cause of diastolic HF. Hypertension is characterized by left ventricular (LV) hypertrophy (LVH). Proinflammatory cytokines are increased in LVH and hypertension, but it is unknown if they mediate the progression of hypertension-induced diastolic HF. We sought to determine if interferon-γ (IFNγ) plays a role in mediating the transition from hypertension-induced LVH to diastolic HF. Twelve-week old BALB/c (WT) and IFNγ-deficient (IFNγKO) mice underwent either saline ( n = 12) or aldosterone ( n = 16) infusion, uninephrectomy, and fed 1% salt water for 4 wk. Tail-cuff blood pressure, echocardiography, and gene/protein analyses were performed. Isolated adult rat ventricular myocytes were treated with IFNγ (250 U/ml) and/or aldosterone (1 μM). Hypertension was less marked in IFNγKO-aldosterone mice than in WT-aldosterone mice (127 ± 5 vs. 136 ± 4 mmHg; P < 0.01), despite more LVH (LV/body wt ratio: 4.9 ± 0.1 vs. 4.3 ± 0.1 mg/g) and worse diastolic dysfunction (peak early-to-late mitral inflow velocity ratio: 3.1 ± 0.1 vs. 2.8 ± 0.1). LV ejection fraction was no different between IFNγKO-aldosterone vs. WT-aldosterone mice. LV end systolic dimensions were decreased significantly in IFNγKO-aldosterone vs. WT-aldosterone hearts (1.12 ± 0.1 vs. 2.1 ± 0.3 mm). Myocardial fibrosis and collagen expression were increased in both IFNγKO-aldosterone and WT-aldosterone hearts. Myocardial autophagy was greater in IFNγKO-aldosterone than WT-aldosterone mice. Conversely, tumor necrosis factor-α and interleukin-10 expressions were increased only in WT-aldosterone hearts. Recombinant IFNγ attenuated cardiac hypertrophy in vivo and modulated aldosterone-induced hypertrophy and autophagy in cultured cardiomyocytes. Thus IFNγ is a regulator of cardiac hypertrophy in diastolic HF and modulates cardiomyocyte size possibly by regulating autophagy. These findings suggest that IFNγ may mediate adaptive downstream responses and challenge the concept that inflammatory cytokines mediate only adverse effects.

Abstract 285: Endoplasmic Reticulum Stress Induces Mitochondrial ROS Overproduction and Contributes to Electrical Remodeling in Heart Failure

2016 ◽  
Vol 119 (suppl_1) ◽  
Author(s):  
Man Liu ◽  
Guangbin Shi ◽  
Dmitry Terentyev ◽  
Anyu Zhou ◽  
Samuel C Dudley
Keyword(s):  
Heart Failure ◽  
Endoplasmic Reticulum ◽  
Er Stress ◽  
Protein Translation ◽  
Heart Tissue ◽  
Confocal Imaging ◽  
Electrical Remodeling ◽  
Patch Clamp Recording ◽  
Protein Levels ◽  
Mitochondrial Ros

Introduction: Heart failure (HF) is associated with endoplasmic reticulum (ER) stress and activation of the unfolded protein response (UPR), which has three branches (PERK, IRE1 and ATF6α). UPR inhibits protein translation, and we hypothesized UPR contributes to electrical remodeling in HF. Methods: HF was induced in C57BL/6 mice 6-7 weeks after unilateral nephrectomy, deoxycorticosterone acetate pellet implantation, and salt water substitution. Sham operated mice were used as controls. Isolated ventricular myocytes were utilized for whole-cell patch clamp recording and ROS measurement by DCFDA with confocal imaging. Heart tissue was used for mRNA and protein measurements. GSK2606414, a specific inhibitor of PERK, was applied to myocytes at 4-30 nM for 6-20 h. Results: The action potential duration was prolonged in HF myocytes (204±26 vs. 100±16 ms of sham, P<0.05). The mRNA and protein levels of the UPR effectors indicated that the PERK and IRE1 branches were activated in HF heart tissue. The peak I Na , I to , I K1 , and I Kslow were decreased significantly in HF group, while I CaL and other K + currents were not affected. A PERK inhibitor, GSK2606414, restored I Na and I K,slow . Current changes were similar to those observed in myocytes under tunicamycin-induced ER stress. Significant reduction of channel protein levels were observed for K v 4.3, Kir2.1, K v 1.5, and Ca v 1.2, but not Na v 1.5, suggesting that I Na reduction was mediated by PERK but not by translational downregulation. Significant ROS production was observed in mouse cardiomyocytes under ER stress, which was suppressed by GSK2606414. Confocal imaging of ROS indicates the source to be mitochondria. Conclusions: TM-treated cardiomyocyte changes indicated that reductions of I Na , I to , I K1 and I K,slow were mediated by ER stress. Proportionally decreased protein and current levels of K v 4.3, Kir2.1, and K v 1.5 suggested direct effects of ER stress. The downregulation of Na v 1.5 and K v 1.5 could be prevented by PERK inhibition. Nevertheless, the effect of PERK inhibition on I Na was indirect and mediated by a PERK-dependent elevation in mitochondrial ROS. In conclusion, the UPR contributes to electrical remodeling in HF by direct and indirect means. Targeting the UPR may be a novel antiarrhythmic strategy.

Heart Failure with Preserved Ejection Fraction – A Review

2012 ◽  
Vol 9 (1) ◽  
pp. 90-95 ◽  
Author(s):  
Otto A Smiseth ◽  
Anders Opdahl ◽  
Espen Boe ◽  
Helge Skulstad
Keyword(s):  
Heart Failure ◽  
Ejection Fraction ◽  
Diastolic Heart Failure ◽  
The Elderly ◽  
Left Ventricular ◽  
Filling Pressure ◽  
Left Ventricular Ejection ◽  
Ventricular Ejection Fraction ◽  
Reduced Ejection Fraction ◽  
Objective Evidence

Heart failure with preserved left ventricular ejection fraction (HF-PEF), sometimes named diastolic heart failure, is a common condition most frequently seen in the elderly and is associated with arterial hypertension and left ventricular (LV) hypertrophy. Symptoms are attributed to a stiff left ventricle with compensatory elevation of filling pressure and reduced ability to increase stroke volume by the Frank-Starling mechanism. LV interaction with stiff arteries aggravates these problems. Prognosis is almost as severe as for heart failure with reduced ejection fraction (HF-REF), in part reflecting co-morbidities. Before the diagnosis of HF-PEF is made, non-cardiac etiologies must be excluded. Due to the non-specific nature of heart failure symptoms, it is essential to search for objective evidence of diastolic dysfunction which, in the absence of invasive data, is done by echocardiography and demonstration of signs of elevated LV filling pressure, impaired LV relaxation, or increased LV diastolic stiffness. Antihypertensive treatment can effectively prevent HF-PEF. Treatment of HF-PEF is symptomatic, with similar drugs as in HF-REF.

scholarly journals Inhibition of the canonical Wnt signaling pathway by a β-catenin/CBP inhibitor prevents heart failure by ameliorating cardiac hypertrophy and fibrosis

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Thanachai Methatham ◽  
Shota Tomida ◽  
Natsuka Kimura ◽  
Yasushi Imai ◽  
Kenichi Aizawa
Keyword(s):  
Heart Failure ◽  
Cardiac Hypertrophy ◽  
Signaling Pathway ◽  
Wnt Signaling Pathway ◽  
Left Ventricular ◽  
Cardiac Wall ◽  
Macrophage Marker ◽  
Glycolysis Pathway ◽  
Canonical Wnt ◽  
Macrophage Accumulation

AbstractIn heart failure (HF) caused by hypertension, the myocyte size increases, and the cardiac wall thickens. A low-molecular-weight compound called ICG001 impedes β-catenin-mediated gene transcription, thereby protecting both the heart and kidney. However, the HF-preventive mechanisms of ICG001 remain unclear. Hence, we investigated how ICG001 can prevent cardiac hypertrophy and fibrosis induced by transverse aortic constriction (TAC). Four weeks after TAC, ICG001 attenuated cardiac hypertrophy and fibrosis in the left ventricular wall. The TAC mice treated with ICG001 showed a decrease in the following: mRNA expression of brain natriuretic peptide (Bnp), Klf5, fibronectin, β-MHC, and β-catenin, number of cells expressing the macrophage marker CD68 shown in immunohistochemistry, and macrophage accumulation shown in flow cytometry. Moreover, ICG001 may mediate the substrates in the glycolysis pathway and the distinct alteration of oxidative stress during cardiac hypertrophy and HF. In conclusion, ICG001 is a potential drug that may prevent cardiac hypertrophy and fibrosis by regulating KLF5, immune activation, and the Wnt/β-catenin signaling pathway and inhibiting the inflammatory response involving macrophages.

scholarly journals Maternal high-fat diet induces metabolic stress response disorders in offspring hypothalamus

2017 ◽  
Vol 59 (1) ◽  
pp. 81-92 ◽  
Author(s):  
Long The Nguyen ◽  
Sonia Saad ◽  
Yi Tan ◽  
Carol Pollock ◽  
Hui Chen
Keyword(s):  
Endoplasmic Reticulum ◽  
Body Weight ◽  
Er Stress ◽  
High Fat Diet ◽  
Maternal Obesity ◽  
Mrna Level ◽  
Metabolic Stress ◽  
High Fat ◽  
Chemical Chaperone ◽  
Protein Levels

Maternal obesity has been shown to increase the risk of obesity and related disorders in the offspring, which has been partially attributed to changes of appetite regulators in the offspring hypothalamus. On the other hand, endoplasmic reticulum (ER) stress and autophagy have been implicated in hypothalamic neuropeptide dysregulation, thus may also play important roles in such transgenerational effect. In this study, we show that offspring born to high-fat diet-fed dams showed significantly increased body weight and glucose intolerance, adiposity and plasma triglyceride level at weaning. Hypothalamic mRNA level of the orexigenic neuropeptide Y (NPY) was increased, while the levels of the anorexigenic pro-opiomelanocortin (POMC), NPY1 receptor (NPY1R) and melanocortin-4 receptor (MC4R) were significantly downregulated. In association, the expression of unfolded protein response (UPR) markers including glucose-regulated protein (GRP)94 and endoplasmic reticulum DNA J domain-containing protein (Erdj)4 was reduced. By contrast, protein levels of autophagy-related genes Atg5 and Atg7, as well as mitophagy marker Parkin, were slightly increased. The administration of 4-phenyl butyrate (PBA), a chemical chaperone of protein folding and UPR activator, in the offspring from postnatal day 4 significantly reduced their body weight, fat deposition, which were in association with increased activating transcription factor (ATF)4, immunoglobulin-binding protein (BiP) and Erdj4 mRNA as well as reduced Parkin, PTEN-induced putative kinase (PINK)1 and dynamin-related protein (Drp)1 protein expression levels. These results suggest that hypothalamic ER stress and mitophagy are among the regulatory factors of offspring metabolic changes due to maternal obesity.

Abstract 18599: Clinical Assessment of Hemodynamic Profiles Predict Readmission and Mortality in Diastolic Heart Failure Patients

Circulation ◽  
2015 ◽  
Vol 132 (suppl_3) ◽  
Author(s):  
Mohammed Siddiqui ◽  
Salpy V Pamboukian ◽  
Jose A Tallaj ◽  
Michael Falola ◽  
Sula Mazimba
Keyword(s):  
Heart Failure ◽  
Clinical Assessment ◽  
Diastolic Heart Failure ◽  
Clinical Care ◽  
Systolic Heart Failure ◽  
Health Care Expenditures ◽  
Left Ventricular ◽  
Readmission Rates ◽  
Heart Failure Patients ◽  
Increased Risk

Background: Reducing 30 day readmission rates for patients with heart failure (HF) has been a recent focus of lowering health care expenditures. Hemodynamic profiles (HP) have been associated with clinical outcomes in chronic systolic HF. The relationship of HP to outcomes in acute decompensated diastolic HF (DHF) has not been defined. Methods: This case-control study of 1892 DHF patients discharged alive from an academic hospital between 2002-2012 with left ventricular function greater or equal to 45% were categorized into 4 groups: Profile A, no evidence of congestion and hypoperfusion (dry-warm); Profile B, congestion with adequate perfusion (wet-warm); Profile C, congestion with hypoperfusion (wet-cold); and Profile L, hypoperfusion without congestion (dry-cold). All cause readmissions at 30 days and 1 year and mortality at 30 days and 1 year were examined. Statistical analysis using multivariable Cox Proportional hazard model was performed adjusting for demographic, clinical, care and hospital characteristics. Results: Of the 1892 patients, 1196 (63%) were females; mean age was 68 (±14) years. There were 724(38%), 1000 (53%), 88(5%) and 80 (4%) patients in the hemodynamic profiles A, B, C and L respectively. Profiles B and C were associated with an increased risk for 30-day all-cause HF readmission compared to profiles A and L: Hazard ratio (HR) [1.38 (95% C.I 1.17-1.61)], [1.39 (95% C.I 1.18-1.62)] for B and C profiles respectively. Profiles C and L were associated with increased mortality at 1 year: HR [1.46 (95% CI 1.06-1.89)] and [1.31 (95% CI 1.01-1.64)] for A and L profiles respectively (Table). Conclusions: Clinical assessment of HP can help identify DHF patients at increased risk of readmission and mortality, similar to systolic heart failure patients.

Myeloid-Derived Growth Factor Protects Against Pressure Overload-Induced Heart Failure by Preserving Sarco/Endoplasmic Reticulum Ca 2+ -ATPase Expression in Cardiomyocytes

Circulation ◽  
2021 ◽  
Author(s):  
Mortimer Korf-Klingebiel ◽  
Marc R. Reboll ◽  
Felix Polten ◽  
Natalie Weber ◽  
Felix Jäckle ◽  
...  
Keyword(s):  
Heart Failure ◽  
Bone Marrow ◽  
Endoplasmic Reticulum ◽  
Growth Factor ◽  
Plasma Concentrations ◽  
Pressure Overload ◽  
Inflammatory Cells ◽  
Left Ventricular ◽  
Neonatal Rat ◽  
Wild Type

Background: Inflammation contributes to the pathogenesis of heart failure, but there is limited understanding of inflammation's potential benefits. Inflammatory cells secrete myeloid-derived growth factor (MYDGF) to promote tissue repair after acute myocardial infarction. We hypothesized that MYDGF has a role in cardiac adaptation to persistent pressure overload. Methods: We defined the cellular sources and function of MYDGF in wild-type, Mydgf -deficient ( Mydgf -/- ), and Mydgf bone marrow-chimeric or bone marrow-conditional transgenic mice with pressure overload-induced heart failure after transverse aortic constriction surgery. We measured MYDGF plasma concentrations by targeted liquid chromatography-mass spectrometry. We identified MYDGF signaling targets by phosphoproteomics and substrate-based kinase activity inference. We recorded Ca 2+ transients and sarcomere contractions in isolated cardiomyocytes. Additionally, we explored the therapeutic potential of recombinant MYDGF. Results: MYDGF protein abundance increased in the left ventricular (LV) myocardium and in blood plasma of pressure-overloaded mice. Patients with severe aortic stenosis also had elevated MYDGF plasma concentrations, which declined after transcatheter aortic valve implantation. Monocytes and macrophages emerged as the main MYDGF sources in the pressure-overloaded murine heart. While Mydgf -/- mice had no apparent phenotype at baseline, they developed more severe LV hypertrophy and contractile dysfunction during pressure overload than wild-type mice. Conversely, conditional transgenic overexpression of MYDGF in bone marrow-derived inflammatory cells attenuated pressure overload-induced hypertrophy and dysfunction. Mechanistically, MYDGF inhibited G protein coupled receptor agonist-induced hypertrophy and augmented sarco/endoplasmic reticulum Ca 2+ ATPase 2a (SERCA2a) expression in cultured neonatal rat cardiomyocytes by enhancing PIM1 serine/threonine kinase expression and activity. Along this line, cardiomyocytes from pressure-overloaded Mydgf -/- mice displayed reduced PIM1 and SERCA2a expression, greater hypertrophy, and impaired Ca 2+ cycling and sarcomere function compared to cardiomyocytes from pressure-overloaded wild-type mice. Transplanting Mydgf -/- mice with wild-type bone marrow cells augmented cardiac PIM1 and SERCA2a levels and ameliorated pressure overload-induced hypertrophy and dysfunction. Pressure-overloaded Mydgf -/- mice were similarly rescued by adenoviral Serca2a gene transfer. Treating pressure-overloaded wild-type mice subcutaneously with recombinant MYDGF enhanced SERCA2a expression, attenuated LV hypertrophy and dysfunction, and improved survival. Conclusions: These findings establish a MYDGF-based adaptive crosstalk between inflammatory cells and cardiomyocytes that protects against pressure overload-induced heart failure.

Abstract 14664: Reduced Activin Like Kinase 1 Activity Promotes Cardiac Fibrosis in Heart Failure

Circulation ◽  
2015 ◽  
Vol 132 (suppl_3) ◽  
Author(s):  
Kevin Morine ◽  
Vikram Paruchuri ◽  
Xiaoying Qiao ◽  
Emily Mackey ◽  
Mark Aronovitz ◽  
...  
Keyword(s):  
Heart Failure ◽  
Cardiac Remodeling ◽  
Cardiac Fibrosis ◽  
Type I Collagen ◽  
Transforming Growth Factor ◽  
Left Ventricular ◽  
Lv Function ◽  
Type I ◽  
Mrna Levels ◽  
Protein Levels

Introduction: Activin receptor like kinase 1 (ALK1) mediates signaling via transforming growth factor beta-1 (TGFb1), a pro-fibrogenic cytokine. No studies have defined a role for ALK1 in heart failure. We tested the hypothesis that reduced ALK1 expression promotes maladaptive cardiac remodeling in heart failure. Methods and Results: ALK1 mRNA expression was quantified by RT-PCR in left ventricular (LV) tissue from patients with end-stage heart failure and compared to control LV tissue obtained from the National Disease Research Interchange (n=8/group). Compared to controls, LV ALK1 mRNA levels were reduced by 85% in patients with heart failure. Next, using an siRNA approach, we tested whether reduced ALK1 levels promote TGFb1-mediated collagen production in human cardiac fibroblasts. Treatment with an ALK1 siRNA reduced ALK1 mRNA levels by 75%. Compared to control, TGFb1-mediated Type I collagen and pSmad-3 protein levels were 2.5-fold and 1.7-fold higher, respectively, after ALK1 depletion. To explore a role for ALK1 in heart failure, ALK1 haploinsufficient (ALK1) and wild-type mice (WT; n=8/group) were studied 2 weeks after thoracic aortic constriction (TAC). Compared to WT, baseline LV ALK1 mRNA levels were 50% lower in ALK1 mice. Both LV and lung weights were higher in ALK1 mice after TAC. Cardiomyocyte area and LV mRNA levels of BNP, RCAN, and b-MHC were increased similarly, while SERCa levels were reduced in both ALK1 and WT mice after TAC. Compared to WT, LV fibrosis (Figure) and Type 1 Collagen mRNA and protein levels were higher among ALK1 mice. Compared to WT, LV fractional shortening (48±12 vs 26±10%, p=0.01) and survival (Figure) were lower in ALK1 mice after TAC. Conclusions: Reduced LV expression of ALK1 is associated with advanced heart failure in humans and promotes early mortality, impaired LV function, and cardiac fibrosis in a murine model of heart failure. Further studies examining the role of ALK1 and ALK1 inhibitors on cardiac remodeling are required.

Abstract 15295: Molecular Mechanism of Chronic Sildenafil-Caused Regression of Heart Failure: Effects on the Express of Cardiac SR Ca2+-ATPase, Subtype of β-Adrenergic Receptors and Nitric Oxide Synthase Isoforms

Circulation ◽  
2014 ◽  
Vol 130 (suppl_2) ◽  
Author(s):  
Heng-Jie Cheng ◽  
Tiankai Li ◽  
Che Ping Cheng
Keyword(s):  
Nitric Oxide ◽  
Heart Failure ◽  
Nitric Oxide Synthase ◽  
Adrenergic Receptors ◽  
Left Ventricular ◽  
Male Rats ◽  
Protein Levels ◽  
Myocyte Function ◽  
Oxide Synthase ◽  
Β Adrenergic Receptors

Background: Sildenafil (SIL), a selective inhibitor of PDE5 has been shown to exert profound beneficial effects in heart failure (HF). Recently we further found that SIL caused regression of cardiac dysfunction in a rat model with isoproterenol (ISO)-induced progressive HF. However, the molecular basis is unclear. We hypothesized that reversal of HF-induced detrimental alterations on the expressions of cardiac SR Ca 2+ -ATPase (SERCA2a), β-adrenergic receptors (AR) and nitric oxide synthase (NOS) isoforms by SIL may play a key role for its salutary role in HF. Methods: Left ventricular (LV) and myocyte function and the protein levels of myocyte β 1 - and β 3 - AR, SERCA2a, phospholamban (PLB) and three NOS were simultaneously evaluated in 3 groups of male rats (6/group): HF , 3 months (M) after receiving ISO (170 mg/kg sq for 2 days); HF/SIL , 2 M after receiving ISO, SIL (70 μg/kg/day sq via mini pump) was initiated and given for 1 M; and Controls (C). Results: Compared with controls, ISO-treated rats progressed to severe HF at 3 M after ISO followed by significantly decreased LV contractility (E ES , HF: 0.7 vs C: 1.2 mmHg/μl) and slowed LV relaxation, reductions in the peak velocity of myocyte shortening (77 vs 136 μm/sec), relengthening (62 vs 104 μm/sec) and [Ca 2+ ] iT (0.15 vs 0.24) accompanied by a diminished myocyte inotropic response to β-AR agonist, ISO (10 -8 M). These abnormalities were associated with concomitant significant decreases in myocyte protein levels of β 1 -AR (0.23 vs 0.64), SERCA2a (0.46 vs 0.80), PLB Ser16 /PLB ratio (0.24 vs 0.40) and eNOS (0.28 vs 0.46), but significantly increases in protein levels of β 3 -AR (0.29 vs 0.10) and iNOS (0.18 vs 0.08) with relatively unchanged nNOS. Chronic SIL prevented the HF-induced decreases in LV and myocyte contraction, relaxation, peak [Ca 2+ ] iT , and restored normal myocyte contractile response to ISO stimulation. With SIL, protein levels of myocyte β 1 - and β 3 -AR, SERCA2a were restored close to control values, but eNOS was significantly elevated than controls (0.77). Conclusions: Chronic SIL prevents HF-caused downregulation of cardiac β 1 -AR and reverse contrast changes between iNOS and β 3 -AR with SERCA 2a and eNOS expression, leading to the preservation of LV and myocyte function, [Ca 2+ ] iT , and β-adrenergic reserve.

Investigation of the Relationship Between Color M-Mode Early Diastolic Propagation Velocity and Left Ventricular Adverse Pressure Gradients

2010 ◽  
Author(s):  
Kelley C. Stewart ◽  
Rahul Kumar ◽  
John J. Charonko ◽  
Pavlos P. Vlachos ◽  
William C. Little
Keyword(s):  
Heart Failure ◽  
Diastolic Dysfunction ◽  
Diastolic Heart Failure ◽  
Diagnostic Techniques ◽  
Left Ventricular Diastolic Dysfunction ◽  
Left Ventricular ◽  
Pressure Gradients ◽  
Compensatory Mechanisms ◽  
Ventricular Diastolic Dysfunction ◽  
The Relationship

Left ventricular diastolic dysfunction (LVDD) and diastolic heart failure are conditions that affect the filling dynamics of the heart and affect 36% of patients diagnosed with congestive heart failure [1]. Although this condition is very prevalent, it currently remains difficult to diagnose due to inherent atrio-ventricular compensatory mechanisms including increased heart rate, increased left ventricular (LV) contractility, and increased left atrial pressure (LA). A greater comprehension of the governing flow physics in the left ventricle throughout the introduction of the heart’s compensatory mechanisms has great potential to substantially increase the understanding of the progression of diastolic dysfunction and in turn advance the diagnostic techniques.

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