Pressure Overload-Induced Cardiac Dysfunction in Aged Male Adiponectin Knockout Mice Is Associated With Autophagy Deficiency

Heart failure is a leading cause of death, especially in the elderly or obese and diabetic populations. Various remodeling events have been characterized, which collectively contribute to the progression of heart failure. Of particular interest, autophagy has recently emerged as an important determinant of cardiac remodeling and function. Here, we used aged, 13-month-old, male adiponectin knockout (Ad-KO) or wild-type (wt) mice subjected to aortic banding to induce pressure overload (PO). Cardiac strain analysis using speckle tracking echocardiography indicated significant dysfunction at an earlier stage in Ad-KO than wt. Analysis of autophagy by Western blotting for Light Chain 3 or microtubule-associated proteins 1B and Sequestosome 1 together with transmission electron microscopy of left ventricular tissue indicated a lack of PO-induced cardiac autophagy in Ad-KO compared with wt mice. Associated with this was mitochondrial degeneration and evidence of enhanced endoplasmic reticulum stress. Western blotting for Light Chain 3 or microtubule-associated proteins 1B, examination of flux using tandem fluoresent tagged-Light Chain 3, and analysis of lysosomal activity in H9c2 cardiac myoblasts treated with adiponectin indicated that adiponectin enhanced autophagy flux. In conclusion, adiponectin directly stimulates autophagic flux and the lack of autophagy in response to PO in aged mice lacking adiponectin may contribute to cellular events which exacerbate the development of cardiac dysfunction.

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Abstract 83: Autophagy Protects the Heart Against Pressure Overload Induced Heart Failure

Circulation Research ◽

10.1161/res.119.suppl_1.83 ◽

2016 ◽

Vol 119 (suppl_1) ◽

Author(s):

Akihiro Shirakabe ◽

Yoshiyuki Ikeda ◽

Toshiro Saito ◽

Peiyong Zhai ◽

Junichi Sadoshima

Keyword(s):

Heart Failure ◽

Cardiac Dysfunction ◽

Sham Group ◽

Pressure Overload ◽

Left Ventricular ◽

Autophagic Flux ◽

Multiple Time ◽

Double Positive ◽

Lung Weight ◽

Multiple Time Points

Autophagy is an important mechanism for the degradation of cytosolic proteins and organelles. We investigated how autophagy is regulated in the heart in response to pressure overload (PO). Mice were subjected to transverse aortic constriction (TAC) at multiple time points between 1 hours and 30 days. Left ventricular (LV) weight/tibial length (TL) was significantly elevated at Day 5 (6.21 ± 0.10 vs 4.59 ± 0.10, p<0.05) and thereafter. Ejection fraction (EF) was maintained at Day 7 (82.1±3.4 vs 78.4±3.2%), but gradually decreased thereafter (at Day 30; 51.0±4.5, p<0.05). The level of LC3II was rapidly increased and peaked at 3 hour (2.4 fold , p<0.05), returned to normal by 24 hours, and then significantly decreased at Day 5 (-40.0%, p<0.05) and thereafter. Autophagic flux was evaluated with tandem fluorescent LC3. At 6 hours, both GFP/RFP double positive (yellow) dots and RFP dots were significantly increased in the TAC group compared to the sham group with or without chloroquine (CQ) (yellow 12±2 vs 4±0 CQ(-), 23±3 vs 9±1 CQ(+); RFP 13±2 vs 5±1 CQ(-), 19±1 vs 13±1 CQ(+)). On the other hand, both yellow and RFP dots were significantly decreased at Day7 and thereafter in the TAC group compared to the sham group with or without CQ. These data suggest that autophagic flux is activated transiently after TAC, but is inactivated after Day 5. To examine the functional significance of autophagy during PO, beclin1 heterozygous KO ( beclin1 -hetKO) mice, atg7 cardiac specific KO (Atg7-CKO) mice, and cardiac-specific U6-shRNA beclin1 (U6shRNA beclin1 ) mice were subjected to TAC. At Day 7 or 14, decreases in EF (60.7 ± 4.8%, 53.8 ± 2.1% and 46.7 ± 5.9%, p<0.05) and increases in lung weight/TL (8.43 ± 0.87, 11.04 ± 4.16 and 18.76 ± 3.77, p<0.05) were exacerbated in beclin1 -hetKO, atg7 -CKO and U6shRNA beclin1 mice compared to in control mice. These results suggest that PO inhibits autophagy after Day5, which coincides with the development of cardiac dysfunction. Since heart failure is exacerbated by further suppression of autophagy, autophagy during PO protects the heart from cardiac dysfunction.

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Abstract 17583: Autophagy Protects the Heart Against Pressure Overload Induced Heart Failure

Circulation ◽

10.1161/circ.132.suppl_3.17583 ◽

2015 ◽

Vol 132 (suppl_3) ◽

Author(s):

Akihiro Shirakabe ◽

Yoshiyuki Ikeda ◽

Peiyong Zai ◽

Toshiro Saito ◽

Junichi Sadoshima

Keyword(s):

Heart Failure ◽

Cardiac Dysfunction ◽

Sham Group ◽

Pressure Overload ◽

Left Ventricular ◽

Autophagic Flux ◽

Aortic Constriction ◽

Double Positive ◽

Lung Weight ◽

Transient Activation

Autophagy is an important mechanism for the degradation of cytosolic proteins and organelles. We investigated how autophagy is regulated in the heart in response to pressure overload (PO). Mice were subjected to transverse aortic constriction (TAC) for multiple durations ranging from 1 hour to 30 days. Left ventricular (LV) weight/tibial length (TL) was significantly elevated at Day 5 (6.21 ± 0.10 vs 4.59 ± 0.10, p<0.05) and thereafter. Ejection fraction (EF) was maintained at Day 7 (82.1±3.4 vs 78.4±3.2%), but gradually decreased thereafter (at Day 30, 51.0±4.5, p<0.05). The level of LC3II increased rapidly, peaking at 3 hours (2.4 fold, p<0.05), returned to normal by 24 hours, and then was significantly decreased at Day 5 (-40.0%, p<0.05) and thereafter. Autophagic flux was evaluated with tandem fluorescent LC3. At 6 hours, both GFP/RFP double positive (yellow) dots and RFP dots were significantly increased in the TAC group compared to the sham group, with or without chloroquine (CQ) (yellow 12±2 vs 4±0 CQ(-), 23±3 vs 9±1 CQ(+); RFP 13±2 vs 5±1 CQ(-), 19±1 vs 13±1 CQ(+)). However, both yellow and RFP dots were significantly decreased at Day 7 and thereafter in the TAC group compared to the sham group, with or without CQ. These data suggest that autophagic flux is activated only transiently after TAC, but is inactivated after Day 5. To examine the functional significance of autophagy during PO, beclin1 heterozygous knockout (beclin1-hetKO) mice, atg7 cardiac-specific knockout (Atg7-CKO) mice, and cardiac-specific U6-shRNA beclin1 (U6shRNAbeclin1) mice were subjected to TAC. At Day 7 and 14 of TAC, decreases in EF (60.7 ± 4.8%, 53.8 ± 2.1% and 46.7 ± 5.9%, p<0.05) and increases in lung weight/TL (8.43 ± 0.87, 11.04 ± 4.16 and 18.76 ± 3.77, p<0.05) were exacerbated in beclin1-hetKO, atg7-CKO and U6shRNAbeclin1 mice compared to in control mice. These results suggest that, after transient activation during the initial 24 hours, PO inhibits autophagy below control levels after Day 5, which coincides with the development of cardiac dysfunction. Since heart failure is exacerbated by further suppression of autophagy, autophagy during PO protects the heart from cardiac dysfunction and PO-induced downregulation of autophagy exacerbates heart failure.

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P1613Brown adipose tissue dysfunction has a critical role for the development of heart failure in murine pressure overload model

European Heart Journal ◽

10.1093/eurheartj/ehz748.0372 ◽

2019 ◽

Vol 40 (Supplement_1) ◽

Author(s):

Y Yoshida ◽

I Shimizu ◽

K Walsh ◽

T Minamino

Keyword(s):

Heart Failure ◽

Adipose Tissue ◽

Body Temperature ◽

Cardiac Dysfunction ◽

Critical Role ◽

Pressure Overload ◽

Left Ventricular ◽

Failing Heart ◽

Brown Adipose

Abstract Prognosis of severe heart failure is unacceptably high, and it is our urgent task to find therapies for this critical condition. It has been reported that low body temperature predicts poor clinical outcomes in patients with heart failure, however, underlying mechanisms and pathological implications are largely unknown. Brown adipose tissue (BAT) was initially characterized as a heat generating organ, and studies suggest that BAT has crucial roles for the maintenance of systemic metabolic health. Here we show that BAT dysfunction develops in a murine thoracic aortic constriction (TAC) model, and has a causal role for promoting pathologies in failing heart. TAC operation led to a significant reduction both in intraperitoneal and subcutaneous temperature. TUNEL-positive cells significantly increased in BAT during left ventricular (LV)-pressure overload, and in-vitro studies with differentiated brown adipocytes suggested that the chronic activation of adrenergic signaling promotes apoptosis in these cells. Gain of BAT function model, generated with BAT implantation into peritoneal cavity, improved thermogenesis and ameliorated cardiac dysfunction in TAC. In contrast, genetic model of BAT dysfunction promoted cardiac dysfunction. Metabolomic analyses showed that BAT dysfunction led to an increase of oxidized choline that promoted metabolic dysfunction in the failing heart. Electron microscope study showed that oxidized choline induced mitochondrial dysfunction in vitro as well as in vivo settings. Extracellular flux analyzerindicated that oxidized choline suppresses oxidative phosphorylation in mitochondria. We found that dilated cardiomyopathy patients have lower body temperature, and confirmed by metabolomic study that both choline and oxidized choline are increased in circulation. Maintenance of BAT homeostasis and suppression of oxidized choline would become a novel therapeutic target for heart failure.

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Oxidative Stress as A Mechanism for Functional Alterations in Cardiac Hypertrophy and Heart Failure

Antioxidants ◽

10.3390/antiox10060931 ◽

2021 ◽

Vol 10 (6) ◽

pp. 931

Author(s):

Anureet K. Shah ◽

Sukhwinder K. Bhullar ◽

Vijayan Elimban ◽

Naranjan S. Dhalla

Keyword(s):

Oxidative Stress ◽

Heart Failure ◽

Angiotensin Ii ◽

Cardiac Hypertrophy ◽

Cardiac Remodeling ◽

Cardiac Dysfunction ◽

Critical Role ◽

Pressure Overload ◽

Hypertrophied Heart ◽

Vasoactive Hormones

Although heart failure due to a wide variety of pathological stimuli including myocardial infarction, pressure overload and volume overload is associated with cardiac hypertrophy, the exact reasons for the transition of cardiac hypertrophy to heart failure are not well defined. Since circulating levels of several vasoactive hormones including catecholamines, angiotensin II, and endothelins are elevated under pathological conditions, it has been suggested that these vasoactive hormones may be involved in the development of both cardiac hypertrophy and heart failure. At initial stages of pathological stimuli, these hormones induce an increase in ventricular wall tension by acting through their respective receptor-mediated signal transduction systems and result in the development of cardiac hypertrophy. Some oxyradicals formed at initial stages are also involved in the redox-dependent activation of the hypertrophic process but these are rapidly removed by increased content of antioxidants in hypertrophied heart. In fact, cardiac hypertrophy is considered to be an adaptive process as it exhibits either normal or augmented cardiac function for maintaining cardiovascular homeostasis. However, exposure of a hypertrophied heart to elevated levels of circulating hormones due to pathological stimuli over a prolonged period results in cardiac dysfunction and development of heart failure involving a complex set of mechanisms. It has been demonstrated that different cardiovascular abnormalities such as functional hypoxia, metabolic derangements, uncoupling of mitochondrial electron transport, and inflammation produce oxidative stress in the hypertrophied failing hearts. In addition, oxidation of catecholamines by monoamine oxidase as well as NADPH oxidase activation by angiotensin II and endothelin promote the generation of oxidative stress during the prolonged period by these pathological stimuli. It is noteworthy that oxidative stress is known to activate metallomatrix proteases and degrade the extracellular matrix proteins for the induction of cardiac remodeling and heart dysfunction. Furthermore, oxidative stress has been shown to induce subcellular remodeling and Ca2+-handling abnormalities as well as loss of cardiomyocytes due to the development of apoptosis, necrosis, and fibrosis. These observations support the view that a low amount of oxyradical formation for a brief period may activate redox-sensitive mechanisms, which are associated with the development of cardiac hypertrophy. On the other hand, high levels of oxyradicals over a prolonged period may induce oxidative stress and cause Ca2+-handling defects as well as protease activation and thus play a critical role in the development of adverse cardiac remodeling and cardiac dysfunction as well as progression of heart failure.

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Very early detection of low dose anti-cancer therapy-related cardiotoxicity in lymphoma patients

European Heart Journal ◽

10.1093/ehjci/ehaa946.3257 ◽

2020 ◽

Vol 41 (Supplement_2) ◽

Author(s):

Y.W Liu ◽

H.Y Chang ◽

C.H Lee ◽

W.C Tsai ◽

P.Y Liu ◽

...

Keyword(s):

Heart Failure ◽

Cancer Therapy ◽

Cardiac Dysfunction ◽

Systolic Dysfunction ◽

Multivariable Analysis ◽

Cardiopulmonary Exercise Test ◽

Left Ventricular ◽

Funding Source ◽

Anti Cancer ◽

All Cause Mortality

Abstract Background and purpose Left ventricular (LV) global peak systolic longitudinal strain (GLS) by speckle-tracking echocardiography is a sensitive modality for the detection of subclinical LV systolic dysfunction and a powerful prognostic predictor. However, the clinical implication of LV GLS in lymphoma patients receiving anti-cancer therapy remains unknown. Methods We prospectively enrolled 74 patients (57.9±17.0 years old, 57% male) with lymphoma who underwent echocardiography prior to chemotherapy, post 3rd and 6th cycle and 1 year after chemotherapy. Cancer therapy-related cardiac dysfunction (CTRCD) is defined as the reduction of absolute GLS value from baseline of ≥15%. All the eligible patients underwent a cardiopulmonary exercise test (CPET) upon completion of 3 cycles of anti-cancer therapy. The primary outcome was defined as a composite of all-cause mortality and heart failure events. Results Among 36 (49%) patients with CTRCD, LV GLS was significantly decreased after the 3rd cycle of chemotherapy (20.1±2.6% vs. 17.5±2.3%, p<0.001). In the multivariable analysis, male sex and anemia (hemoglobin <11 g/dL) were found to be independent risk factors of CTRCD. Objectively, patients with CTRCD had lower minute oxygen consumption/kg (VO2/kg) and lower VO2/kg value at anaerobic threshold in the CPET. The incidence of the primary composite outcome was higher in the CTRCD group than in the non-CTRCD group (hazard ratio 3.21; 95% CI, 1.04–9.97; p=0.03). Conclusion LV GLS is capable of detecting early cardiac dysfunction in lymphoma patients receiving anti-cancer therapy. Patients with CTRCD not only had a reduced exercise capacity but also a higher risk of all-cause mortality and heart failure events. Change of LVEF and GLS after cancer Tx Funding Acknowledgement Type of funding source: Public grant(s) – National budget only. Main funding source(s): The Ministry of Science and Technology (MOST), Taiwan

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Abstract 1213: Cardiac Overexpression of Epac1 in Transgenic Mice Protects Heart from Lipopolysaccharide-induced Cardiac Dysfunction and Inhibits JAK-STAT Pathway

Circulation ◽

10.1161/circ.116.suppl_16.ii_246-b ◽

2007 ◽

Vol 116 (suppl_16) ◽

Author(s):

Satoshi Okumura ◽

Yunzhe Bai ◽

Meihua Jin ◽

Sayaka Suzuki ◽

Akiko Kuwae ◽

...

Keyword(s):

Heart Failure ◽

Cyclic Amp ◽

Transgenic Mice ◽

Cardiac Function ◽

Proinflammatory Cytokines ◽

Cardiac Dysfunction ◽

Left Ventricular ◽

Left Ventricular Ejection ◽

Ventricular Ejection Fraction ◽

Stat Pathway

The sympathetic nervous system and proinflammatory cytokines are believed to play independent roles in the pathophysiology of heart failure. However, the recent identification of Epac (exchange protein activated by cyclic AMP), a new cyclic AMP-binding protein that directly activates Rap1, have implicated that there may be a potential cross talk between the sympathetic and cytokine signals. In order to examine the role of Epac in cytokine signal to regulate cardiac function, we have generated transgenic mice expressing the human Epac1 gene under the control of alpha-cardiac myosin heavy chain promoter (Epac1-TG), and examined their response in lipopolysaccharide (LPS)-induced cardiac dysfunction, a well established model for sepsis-induced cardiac dysfunction. Sepsis-induced cardiac dysfunction results from the production of proinflammatory cytokines. At baseline, left ventricular ejection fraction (LVEF) was similar (TG vs. NTG, 67±1.7 vs. 69±2.1%, n =7–9). The degree of cardiac hypertrophy (LV(mg)/tibia(mm)) was also similar at 3 months old (TG vs. NTG 4.0±0.1 vs. 4.2±0.1, n =5–6), but it became slightly but significantly greater in Epac1-TG at 5 month old (TG vs. NTG 4.9±0.1 vs. 4.4±0.1, p< 0.05, n =5–7). LPS (5mg/kg) elicited a significant and robust reduction of LVEF in both Epac1-TG and NTG, but the magnitude of this decrease was much less in Epac1-TG at 6 hr after injection (TG vs. NTG 48±2.4 vs. 57±1.8%, p< 0.01, n =6–9). At 24 hr after injection, cardiac function was restored to the baseline in both Epac1-TG and NTG. We also examined the activation of JAK-STAT pathway at 24 hr after injection. The tyrosine phosphorylation of STAT1 (Tyr701) and STAT3 (Tyr705) in LV, which is an indicator of STAT activation, was reduced to a greater degree in Epac1-TG by 31±8.8% ( p< 0.05, n =4) and 29±5.9% ( p< 0.05, n =7), respectively, relative to that in NTG. Taken together, Epac1 protects the heart from the cytokine-induced cardiac dysfunction, at least in part, through the inhibition of the JAK-STAT pathway, suggesting the beneficial role played by sympathetic signal to antagonize proinflammatory cytokine signal in heart failure.

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Abstract P352: An Antiplatelet Agent Sarpogrelate Suppresses Pressure Overload-induced Development Of Heart Failure In A 5-ht 2a Receptor-independent Manner

Circulation Research ◽

10.1161/res.129.suppl_1.p352 ◽

2021 ◽

Vol 129 (Suppl_1) ◽

Author(s):

Kana Shimizu ◽

Masafumi Funamoto ◽

Yoichi Sunagawa ◽

Yasufumi Katanasaka ◽

Yusuke Miyazaki ◽

...

Keyword(s):

Heart Failure ◽

Western Blotting ◽

Drug Repositioning ◽

Antiplatelet Agent ◽

Left Ventricular ◽

Antiplatelet Drug ◽

Cardiomyocyte Hypertrophy ◽

Sham Operation ◽

Mrna Levels ◽

Independent Manner

Purpose: The cost of new drug development is increasing year by year, and drug repositioning is being used as a strategy to develop new treatments at low-cost. We used a library of approved drugs to screen for compounds that suppress cardiomyocyte hypertrophy, and identified as a candidate the antiplatelet drug sarpogrelate, a selective serotonin-2A (5-HT 2A ) receptor antagonist. In this study, we examined the effect of sarpogrelate on cultured cardiomyocyte hypertrophy and development of heart failure. Methods & Results: First, primary cultured cardiomyocytes were treated with 1 μM sarpogrelate and then stimulated with various hypertrophic stimuli (30 μM phenylephrine (PE), 0.1 μM angiotensin II and 0.1 μM endothelin 1). The results of immunofluorescence staining with anti-MHC antibody showed that sarpogrelate significantly suppressed cardiomyocyte hypertrophy induced by each stimulus. Western blotting and qPCR analysis showed that the mRNA and protein levels of 5-HT 2A receptor did not change by PE, and sarpogrelate significantly suppressed PE-induced phosphorylation of ERK1/2 and GATA4. Next, C57BL/6j male mice were subjected to a transverse aortic constriction (TAC) and sham operation. One day after the operation, the mice were randomly divided into 3 groups: sarpogrelate at 1 mg/kg or 5 mg/kg, and vehicle as a control. Daily oral administration was repeated for 8 weeks. Echocardiographic analysis showed that 5 mg/kg sarpogrelate significantly prevented a TAC-induced increase in posterior left ventricular wall thickness and a decrease in fractional shortening at 8 weeks after the operation. Five mg/kg sarpogrelate also suppressed TAC-induced increase in HW/BW ratio, cross-sectional areas, perivascular fibrosis, and mRNA levels of ANF and BNP. Moreover, the western blotting analysis showed that 5 mg/kg sarpogrelate significantly suppressed TAC-induced phosphorylation of ERK1/2. Conclusions: These results indicate that sarpogrelate significantly suppresses cardiomyocyte hypertrophy and the development of heart failure via at least, in part, by inhibition of ERK1/2-GATA4 pathway. These findings suggest that sarpogrelate may be an effective agent for heart failure therapy.

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

Circulation ◽

10.1161/circulationaha.120.053365 ◽

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.

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Abstract P210: Central Blockade Of Tumor Necrosis Factor-Á-Converting Enzyme (tace) Ameliorates Neuroinflammation, Sympathetic Excitation And Cardiac Dysfunction In Heart Failure Rat

Hypertension ◽

10.1161/hyp.78.suppl_1.p210 ◽

2021 ◽

Vol 78 (Suppl_1) ◽

Author(s):

Yang Yu ◽

Baojian Xue ◽

Hanzeng Li ◽

Qing Chen ◽

Mingxuan Li ◽

...

Keyword(s):

Heart Failure ◽

Body Weight ◽

Growth Factor ◽

Tumor Necrosis Factor ◽

Cardiac Dysfunction ◽

Tumor Necrosis ◽

Left Ventricular ◽

Male Rats ◽

Tnf Α ◽

Necrosis Factor

TACE is a key metalloprotease involved in ectodomain shedding of tumor necrosis factor (TNF)-α and transforming growth factor (TGF)-α. We previously reported that TACE-mediated production of TNF-α in the hypothalamic paraventricular nucleus (PVN) contributes to the sympathetic excitation in heart failure (HF). Additionally, the upregulated TGF-α in the PVN transactivates the epidermal growth factor receptor (EGFR) to activate extracellular signal-regulated kinase (ERK) 1/2 in HF. Here we sought to determine whether central inhibition of TACE attenuates neuroinflammation and prevents the progress of HF. Male rats underwent coronary artery ligation to induce HF or sham surgery (Sham). These rats were treated with bilateral PVN microinjection of a TACE siRNA or control siRNA while some rats received a 4-week intracerebroventricular (ICV) infusion of TACE inhibitor TAPI-0 or vehicle. Compared with Sham rats, HF rats treated with control siRNA, had higher (*P<0.05) levels of TNF-α (7.88±1.32* vs 2.77±0.98 pg/mL) and TGF-α (28.27±2.76* vs 11.62±2.48 pg/mL) in cerebrospinal fluid, and increased mRNA expression of TACE (2.53±0.30* vs 1.04±0.12), TNF-α (3.43±0.55* vs 1.03±0.11), TNF-α receptor 1 (2.32±0.27* vs 1.07±0.19), cyclooxygenase-2 (2.96±0.31* vs 1.10±0.19) and TGF-α (2.68±0.41* vs 1.06±0.14) in the PVN, but these levels were markedly reduced (39-54%*) in TACE siRNA-treated HF rats. Compared with control HF rats, HF rats treated with TACE siRNA had reduced expression of phosphorylated (p-) NF-κB p65 (1.27±0.14 vs 0.84±0.07*), p-EGFR (0.52±0.05 vs 0.37±0.04*) and p-ERK1/2 (1.06±0.10 vs 0.62±0.09*) in the PVN. Moreover, the elevated plasma norepinephrine levels, lung/body weight, heart/body weight and left ventricular (LV) end-diastolic pressure along with decreased LV dP/dt max in HF rats-treated with control siRNA were significantly attenuated in HF rats treated with TACE siRNA. Treatments with TACE siRNA in the PVN also improved the indicators of cardiac hypertrophy and fibrosis of HF. ICV infusion of TAPI-0 had the similar effects with PVN TACE siRNA on these variables in HF. These data indicate that central interventions suppressing TACE activity ameliorate neuroinflammation, sympathetic activation and cardiac dysfunction in HF.

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Abstract 285: Cardiac Inflammation and Fibrosis Induced by Heart Failure Are Reversed by Short-Duration Estrogen Therapy

Circulation Research ◽

10.1161/res.111.suppl_1.a285 ◽

2012 ◽

Vol 111 (suppl_1) ◽

Author(s):

Andrea Iorga ◽

Rangarajan Nadadur ◽

Salil Sharma ◽

Jingyuan Li ◽

Mansoureh Eghbali

Keyword(s):

Heart Failure ◽

Estrogen Therapy ◽

Pressure Overload ◽

Decompensated Heart Failure ◽

Left Ventricular ◽

Neonatal Rat ◽

In Vivo Model ◽

Anti Inflammatory

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.

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