Abstract 15674: Notch3/rbpjk Signaling Pathway in the Coronary Arteries is Involved in the Development of Heart Failure in Response to Hypertension

Circulation ◽  
2014 ◽  
Vol 130 (suppl_2) ◽  
Author(s):  
Astrid Monfort ◽  
Hélène Ragot ◽  
Evelyne Polidano ◽  
Regine Merval ◽  
Claude Delcayre ◽  
...  

Background: Notch3, a receptor expressed in vascular smooth muscle cells (VSMC), plays a key role in the integrity of resistance arteries by controlling the maturation of VSMC through RBPJk, a canonical Notch transcriptional factor. We hypothesized that Notch3 signaling pathway in the VSMCs of the coronary arteries might play a key role in the cardiac adaptation to pressure-overload. Methods: To eliminate congenital defect biases, we used mice in which conditional tamoxifen- selective deletion of RBPJk in VSMC was induced at the age of 4 weeks (SMMHC-CRE ER T2, RBP-JK loxp/loxp). Seven weeks later, hypertension was induced in control (C) mice (n= 10) and those with RBPJk deletion (SM-RBPJ-KO, n = 13) by infusion of Angiotensin 2 (Ang2) (1μg/kg/min) using Alzet minipumps after surgery. Results: In response to Ang2, SM-RBPJ-KO and control mice showed similar hypertension (159 ±7 mmHg vs 150±10 mmHg). By day 8 after surgery, SM-RBPJ-KO mice only developed a severe heart failure with anarsaca. These mice showed a decrease in shortening fraction (-42%, p<0.01), a left ventricular dilatation (+15%, p<0.01), and a ventricular hypertrophy (+12%, p<0.05) when compared to C + Ang2. As expected, C + Ang 2 hearts showed an increase in ANP, B-MHC and Gal-3 (+76%, +55%, +46%, p<0.05 respectively vs C) mRNA expressions, whereas SM-RBPJ-KO hearts exhibited even higher induction of ANP (+48%, p<0.01), Gal-3 (+74%, p<0.01), CD68 (+55%, p<0.05) and collagen-3 (+78%, p<0.01) when compared to C + Ang2. This cardiac phenotype confirmed the severe heart failure. Interestingly, immuno-morphometric analysis showed an arteriolar rarefaction in SM-RBPJ-KO + Ang2 mice associated with a lack of angiogenic signaling pathway revealed by a decrease in VEGFa and angiopoietin 2 mRNAs (-50%, and -52%, p<0.05, respectively vs. C + Ang2). Conclusion: We provide evidence that in adulthood, dysfunction of the Notch3/RBPJk signaling pathway in the coronary arteries contributes in the aggravation of heart failure in response to rapid increase in blood pressure.

2021 ◽  
Vol 42 (Supplement_1) ◽  
Author(s):  
J Van Wauwe ◽  
S Craps ◽  
A Zwijsen ◽  
M Beerens ◽  
A Luttun

Abstract Introduction PR-domain containing 16 (Prdm16) has an asymmetric expression pattern in the developing cardiovascular system, including ventricular myocardium, endocardium and arterial endothelial and smooth muscle cell (SMC) layers. Heterozygous PRDM16 mutations in humans have been linked with early-onset cardiomyopathy resulting in heart failure. Myocardial PRDM16-deficiency has been suggested as the culprit for this cardiomyopathy, however embryonic Prdm16 deletion in cardiomyocytes or their progenitors in mice only results in symptomatic cardiac defects upon metabolic stress or ageing. This suggests that Prdm16 loss in other cell types has an important co-contribution in the early heart phenotype seen in patients with causal PRDM16 variants. Purpose To investigate the adjuvant role of non-cardiomyocytes to the heart phenotype caused by Prdm16 deficiency, we used a conditional mouse model in which deletion of Prdm16 occurs in all cells expressing an Sm22-driven Cre recombinase which has a combined activity in cardiomyocyte and non-cardiomyocyte lineages in the heart, including SMCs and pericytes. Methods Mice carrying two Prdm16 alleles with a floxed exon 9 (Prdm16fl/fl) were intercrossed with the Sm22-Cre driver line. Offspring of Sm22Cre+; Prdm16fl/fl and Sm22Cre−; Prdm16fl/fl breeding pairs was monitored for Mendelian inheritance and for signs of (progressive) cardiac dysfunction by echocardiography at 5 and 16 weeks of age. Hearts were isolated and analyzed for RNA expression levels of cardiac stress markers Atrial and Brain Natriuretic Peptide (ANP and BNP) via quantitative RT-PCR and histologically for the appearance of fibrosis through Sirius red-staining. Results Genotyping at 5 weeks of age showed a loss of 60.4% of Sm22Cre+; Prdm16fl/fl offspring. Mice surviving at 5 weeks spontaneously developed signs of left ventricular diastolic and systolic dysfunction, the latter shown by a significantly reduced ejection fraction (EF; 37±3% vs. 61±3% in control Sm22Cre−; Prdm16fl/fl littermates). Cardiac expression levels of ANP and BNP were significantly increased (728-fold and 36-fold, respectively) in Sm22Cre+; Prdm16fl/fl mice which also showed perivascular fibrosis compared to control littermates. At 16 weeks of age, this aberrant cardiac phenotype further progressed (EF: 32±3% vs. 57±4%; ANP: 2,541-fold increase; BNP: 129-fold increase) and in addition to perivascular fibrosis, hearts also showed interstitial fibrosis (Sirius red+ area: 17±2% vs. 3.0±0.4% in control littermates). Conclusion Unlike recently reported mice with a Prdm16 deficiency in cardiomyocytes or their (precursor) lineages, mice with a combined loss of Prdm16 in the cardiomyocytes and certain non-cardiomyocyte lineages feature early mortality and (progressive) signs of severe heart failure. Therefore, Prdm16 expressed by non-cardiomyocytes is indispensable for proper cardiac function and its loss in these cell types co-determines the aberrant cardiac phenotype. FUNDunding Acknowledgement Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Fonds voor Wetenschappelijk Onderzoek Strategic Basic Research pre-doctoral fellowship (1S25817N)KU Leuven Research Coordination grant (C14/19/095)


2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
Y Hsiao ◽  
I Shimizu ◽  
T Wakasugi ◽  
S Jiao ◽  
T Watanabe ◽  
...  

Abstract Background/Introduction Mitochondria are dynamic regulators of cellular metabolism and homeostasis. The dysfunction of mitochondria has long been considered a major contributor to aging and age-related diseases. The prognosis of severe heart failure is still unacceptably poor and it is urgent to establish new therapies for this critical condition. Some patients with heart failure do not respond to established multidisciplinary treatment and they are classified as “non-responders”. The outcome is especially poor for non-responders, and underlying mechanisms are largely unknown. Purpose Studies indicate mitochondrial dysfunction has causal roles for metabolic remodeling in the failing heart, but underlying mechanisms remain to be explored. This study tried to elucidate the role of Mitofusin-1 in a failing heart. Methods We examined twenty-two heart failure patients who underwent endomyocardial biopsy of intraventricular septum. Patients were classified as non-responders when their left-ventricular (LV) ejection fraction did not show more than 10% improvement at remote phase after biopsy. Fourteen patients were classified as responders, and eight as non-responders. Electron microscopy, quantitative PCR, and immunofluorescence studies were performed to explore the biological processes or molecules involved in failure to respond. In addition to studies with cardiac tissue specific knockout mice, we also conducted functional in-vitro studies with neonatal rat ventricular myocytes. Results Twenty-two patients with IDCM who underwent endomyocardial biopsy were enrolled in this study, including 14 responders and 8 non-responders. Transmission electron microscopy (EM) showed a significant reduction in mitochondrial size in cardiomyocytes of non-responders compared to responders. Quantitative PCR revealed that transcript of mitochondrial fusion protein, Mitofusin-1, was significantly reduced in non-responders. Studies with neonatal rat ventricular myocytes (NRVMs) indicated that the beta-1 adrenergic receptor-mediated signaling pathway negatively regulates Mitofusin-1 expression. Suppression of Mitofusin-1 resulted in a significant reduction in mitochondrial respiration of NRVMs. We generated left ventricular pressure overload model with thoracic aortic constriction (TAC) in cardiac specific Mitofusin-1 knockout model (c-Mfn1 KO). Systolic function was reduced in c-Mfn1 KO mice, and EM study showed an increase in dysfunctional mitochondria in the KO group subjected to TAC. Conclusions Mitofusin-1 becomes a biomarker for non-responders with heart failure. In addition, our results suggest that therapies targeting mitochondrial dynamics and homeostasis would become next generation therapy for severe heart failure patients. Funding Acknowledgement Type of funding source: None


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Thanachai Methatham ◽  
Shota Tomida ◽  
Natsuka Kimura ◽  
Yasushi Imai ◽  
Kenichi Aizawa

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.


Open Medicine ◽  
2011 ◽  
Vol 6 (1) ◽  
pp. 11-25
Author(s):  
Enrico Vizzardi ◽  
Tania Bordonali ◽  
Elena Tanghetti ◽  
Marco Metra ◽  
Livio Cas

AbstractAnaemia is one of the most frequent co-morbidities in patients with heart failure. Its prevalence increases from 4% to7% in subjects with asymptomatic left ventricular dysfunction to >30% in patients with severe heart failure. Renal insufficiency, activation of inflammatory mediators and treatment with renin-angiotensin antagonists seem to be its main determinants. The results of many studies agree in providing evidence that anaemia is a powerful independent determinant of survival in patients with heart failure. However, the mechanisms of this relation are still not fully understood. Moreover a favourable effect of the correction of anaemia on prognosis has not yet been shown. Also In addition to this, controlled studies assessing its effects on exercise tolerance have yielded controversial results. Further research is needed to assess the effect of correcting anaemia in chronic heart failure (CHF) patients; ongoing reduction of events with RED-HF (Darbepoetin alpha in heart failure) trial will help define the role.


1989 ◽  
Vol 14 (1) ◽  
pp. 127-134 ◽  
Author(s):  
Constantine N. Aroney ◽  
Howard C. Herrmann ◽  
Marc J. Semigran ◽  
G. William ◽  
Charles A. Boucher ◽  
...  

Author(s):  
Mortimer Korf-Klingebiel ◽  
Marc R. Reboll ◽  
Felix Polten ◽  
Natalie Weber ◽  
Felix Jäckle ◽  
...  

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.


2012 ◽  
Vol 111 (suppl_1) ◽  
Author(s):  
Andrea Iorga ◽  
Rangarajan Nadadur ◽  
Salil Sharma ◽  
Jingyuan Li ◽  
Mansoureh Eghbali

Heart failure is generally characterized by increased fibrosis and inflammation, which leads to functional and contractile defects. We have previously shown that short-term estrogen (E2) treatment can rescue pressure overload-induced decompensated heart failure (HF) in mice. Here, we investigate the anti-inflammatory and anti-fibrotic effects of E2 on reversing the adverse remodeling of the left ventricle which occurs during the progression to heart failure. Trans-aortic constriction procedure was used to induce HF. Once the ejection fraction reached ∼30%, one group of mice was sacrificed and the other group was treated with E2 (30 αg/kg/day) for 10 days. In vitro, co-cultured neonatal rat ventricular myocytes and fibroblasts were treated with Angiotensin II (AngII) to simulate cardiac stress, both in the presence or absence of E2. In vivo RT-PCR showed that the transcript levels of the pro-fibrotic markers Collagen I, TGFβ, Fibrosin 1 (FBRS) and Lysil Oxidase (LOX) were significantly upregulated in HF (from 1.00±0.16 to 1.83±0.11 for Collagen 1, 1±0.86 to 4.33±0.59 for TGFβ, 1±0.52 to 3.61±0.22 for FBRS and 1.00±0.33 to 2.88±0.32 for LOX) and were reduced with E2 treatment to levels similar to CTRL. E2 also restored in vitro AngII-induced upregulation of LOX, TGFβ and Collagen 1 (LOX:1±0.23 in CTRL, 6.87±0.26 in AngII and 2.80±1.5 in AngII+E2; TGFβ: 1±0.08 in CTRL, 3.30±0.25 in AngII and 1.59±0.21 in AngII+E2; Collagen 1: 1±0.05 in CTRL.2±0.01 in AngII and 0.65±0.02 (p<0.05, values normalized to CTRL)). Furthermore, the pro-inflammatory interleukins IL-1β and IL-6 were upregulated from 1±0.19 to 1.90±0.09 and 1±0.30 to 5.29±0.77 in the in vivo model of HF, respectively, and reversed to CTRL levels with E2 therapy. In vitro, IL-1β was also significantly increased ∼ 4 fold from 1±0.63 in CTRL to 3.86±0.14 with AngII treatment and restored to 1.29±0.77 with Ang+E2 treatment. Lastly, the anti-inflammatory interleukin IL-10 was downregulated from 1.00±0.17 to 0.49±0.03 in HF and reversed to 0.67±0.09 in vivo with E2 therapy (all values normalized to CTRL). This data strongly suggests that one of the mechanisms for the beneficial action of estrogen on left ventricular heart failure is through reversal of inflammation and fibrosis.


2001 ◽  
Vol 31 (11) ◽  
pp. 1159
Author(s):  
Hainan Piao ◽  
Jin Sook Kwon ◽  
Hye Young Lee ◽  
Tae Jin Youn ◽  
Dong Woon Kim ◽  
...  

2011 ◽  
Vol 68 (11) ◽  
pp. 979-984
Author(s):  
Sergej Prijic ◽  
Sanja Rakic ◽  
Ljubica Nikolic ◽  
Bosiljka Jovicic ◽  
Mila Stajevic ◽  
...  

Introduction. Levosimendan is a novel positive inotropic agent which, improves myocardial contractility through its calcium-sensitizing action, without causing an increase in myocardial oxygen demand. Also, by opening ATP-sensitive potassium channels, it causes vasodilatation with the reduction in both afterload and preload. Because of the long halflife, its effects last for up 7 to 9 days after 24-hour infusion. Case report. We presented three patients 2, 15 and 17 years old. All the patients had severe acute deterioration of the previously diagnosed chronic heart failure (dilatative cardiomyopathy; univentricular heart with bidirectional Glenn anastomosis and restrictive bulboventricular foramen; bacterial endocarditis on artificial aortic valve with severe stenosis and regurgitation). Signs and symptoms of severe heart failure, cardiomegaly (cardio-thoracic index 0.65) and left ventricular dilatation (end-diastolic diameter z-score 2.6; 4.1 and 4.0) were confirmed on admission. Also, myocardial contractility was poor with ejection fraction (EF - 27%, 25%, 35%), fractional shortening (FS - 13%, 11%, 15%) and stroke volume (SV - 40, 60, 72 mL/m2). The treatment with standard intravenous inotropic agents resulted in no improvement but in clinical deterioration. Thus, standard intravenous inotropic support was stopped and levosimendan treatment was introduced. All the patients received a continuous 24-h infusion 0.1 ?g/kg/min of levosimendan. In a single patient an initial loading dose of 11 ?g/kg over 10 min was administrated, too. Levosimendan treatment resulted in both clinical and echocardiography improvement with the improved EF (42%, 34%, 44%), FS (21%, 16%, 22%) and SV (59, 82, 93 mL/m2). Hemodynamic improvement was registered too, with the reduction in heart rate in all the treated patients from 134-138 bpm before, to less than 120 bpm after the treatment. These parameters were followed by the normalization of lactate levels. Nevertheless, left ventricular end-diastolic diameter did not change after the levosimendan treatment. Conclusion. Our initial experience demonstrates that administration of levosimendan in patients with severe chronic heart failure not responsive to standard intravenous inotropic treatment might result in a significant clinical and hemodynamic improvement and that, in selected patients, it might be life saving. According to our best knowledge patients presented are the first pediatric patients treated with levosimendan in our country.


2020 ◽  
pp. 609-620 ◽  
Author(s):  
M Popková ◽  
E Kuriščák ◽  
P Hála ◽  
D Janák ◽  
L Tejkl ◽  
...  

Veno-arterial extracorporeal membrane oxygenation (VA ECMO) is a technique used in patients with severe heart failure. The aim of this study was to evaluate its effects on left ventricular afterload and fluid accumulation in lungs with electrical impedance tomography (EIT). In eight swine, incremental increases of extracorporeal blood flow (EBF) were applied before and after the induction of ischemic heart failure. Hemodynamic parameters were continuously recorded and computational analysis of EIT was used to determine lung fluid accumulation. With an increase in EBF from 1 to 4 l/min in acute heart failure the associated increase of arterial pressure (raised by 44 %) was accompanied with significant decrease of electrical impedance of lung regions. Increasing EBF in healthy circulation did not cause lung impedance changes. Our findings indicate that in severe heart failure EIT may reflect fluid accumulation in lungs due to increasing EBF.


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