Long noncoding RNA NEAT1 promotes cardiac fibrosis in heart failure through increased recruitment of EZH2 to the Smad7 promoter region

AbstractCardiac fibrosis, a well-known major pathological process that ultimately leads to heart failure, has attracted increasing attention and focus in recent years. A large amount of research indicates that long noncoding RNAs (lncRNAs) play an important role in cardiac fibrosis, but little is known about the specific function and mechanism of the lncRNA NEAT1 in the progression of cardiac fibrosis to heart failure. In the present study, we have demonstrated that the lncRNA NEAT1 is upregulated in patients with heart failure. Similarly, the expression of Neat1 was also increased in the left ventricular tissue of transverse aortic constriction (TAC) surgery mice and cardiac fibroblasts treated with TGF-β1. Further, gain-of-function and loss-of-function experiments showed that silencing of Neat1 attenuated cardiac fibrosis, while overexpression of Neat1 with adenovirus significantly aggravated the in vitro progression of fibrosis. With regard to the underlying mechanism, our experiments showed that Neat1 recruited EZH2 to the promoter region of Smad7 through physical binding of EZH2 to the promoter region, as a result of which Smad7 expression was inhibited and the progression of cardiac fibrosis was ultimately exacerbated. We found that the introduction of shNeat1 carried by adeno-associated virus-9 significantly ameliorated cardiac fibrosis and dysfunction caused by TAC surgery in mice. Overall, our study findings demonstrate that the lncRNA Neat1 accelerates the progression of cardiac fibrosis and dysfunction by recruiting EZH2 to suppress Smad7 expression. Thus, NEAT1 may serve as a target for the treatment of cardiac fibrosis.

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Th1 effector T cells selectively orchestrate cardiac fibrosis in nonischemic heart failure

Journal of Experimental Medicine ◽

10.1084/jem.20161791 ◽

2017 ◽

Vol 214 (11) ◽

pp. 3311-3329 ◽

Cited By ~ 46

Author(s):

Tania Nevers ◽

Ane M. Salvador ◽

Francisco Velazquez ◽

Njabulo Ngwenyama ◽

Francisco J. Carrillo-Salinas ◽

...

Keyword(s):

Heart Failure ◽

T Cells ◽

Cardiac Fibrosis ◽

Cardiac Fibroblasts ◽

Th1 Cells ◽

Dependent Manner ◽

Effector Cells ◽

Ifn Γ

Despite emerging data indicating a role for T cells in profibrotic cardiac repair and healing after ischemia, little is known about whether T cells directly impact cardiac fibroblasts (CFBs) to promote cardiac fibrosis (CF) in nonischemic heart failure (HF). Recently, we reported increased T cell infiltration in the fibrotic myocardium of nonischemic HF patients, as well as the protection from CF and HF in TCR-α−/− mice. Here, we report that T cells activated in such a context are mainly IFN-γ+, adhere to CFB, and induce their transition into myofibroblasts. Th1 effector cells selectively drive CF both in vitro and in vivo, whereas adoptive transfer of Th1 cells, opposite to activated IFN-γ−/− Th cells, partially reconstituted CF and HF in TCR-α−/− recipient mice. Mechanistically, Th1 cells use integrin α4 to adhere to and induce TGF-β in CFB in an IFN-γ–dependent manner. Our findings identify a previously unrecognized role for Th1 cells as integrators of perivascular CF and cardiac dysfunction in nonischemic HF.

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Long Noncoding RNA DICER1-AS1 Functions in Methylation Regulation on the Multi-Drugresistance of Osteosarcoma Cells via miR-34a-5p and GADD45A

Frontiers in Oncology ◽

10.3389/fonc.2021.685881 ◽

2021 ◽

Vol 11 ◽

Author(s):

Feng Wang ◽

Lingsuo Kong ◽

Youguang Pu ◽

Fengmei Chao ◽

Chunbao Zang ◽

...

Keyword(s):

Drug Resistance ◽

Therapeutic Target ◽

Promoter Region ◽

Noncoding Rna ◽

Expression Profiles ◽

Methylation Status ◽

Rna Seq ◽

Loss Of Function ◽

Potential Biomarker

Osteosarcoma (OS) is a common malignant bone tumor that commonly occurs in children and adolescents. Long noncoding RNAs (lncRNAs) are recognized as a novel class of regulators of gene expression associated with tumorigenesis. However, the effect and mechanism of lncRNAs in OS tumorigenesis and drug resistance have not been characterized. The purpose of the study is to screen potential biomarker and therapeutic target against OS. We compared the lncRNA expression profiles between OS cell lines with different drug resistance levels using RNA-seq analysis and found that lncRNA DICER1-AS1 was significantly differentially expressed in multi-drugresistant OS cells SJSA-1 versus multi-drugsensitive OS cells G-292. Bisulfite Sequencing PCR (BSP) assay was performed to analyze the differential methylation status of the promoter region of DICER1-AS1 in four OS cells. Subsequently, in vitro gain- and loss-of-function experiments demonstrated the roles of DICER1-AS1 and miR-34a-5p in the multi-drugresistance of OS cells. The main findings is that DICER1-AS1 directly binds to miR-34a-5p, and their expression has a negative correlation with each other. The hypermethylation of the promoter region of DICER1-AS1 silenced its expression in the drugresistant cells SJSA-1 and MNNG/HOS. Moreover, we found that growth arrest and DNA damage-inducible alpha (GADD45A) participates in the DICER1-AS1/miR-34a-5p-regulated drug resistance of OS cells, probably via the cell cycle/pRb-E2F pathway. Our results revealed DICER1-AS1/miR-34a-5p-regulated drug resistance of OS cells, a new lncRNA-regulated network in OS tumorigenesis, suggested that DICER1-AS1 can be considered as a potential biomarker and therapeutic target against OS cells.

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Cholinergic Elicitation Prevents Ventricular Remodeling via Alleviations of Myocardial Mitochondrial Injury Linked to Inflammation in Ischemia-Induced Chronic Heart Failure Rats

Mediators of Inflammation ◽

10.1155/2021/4504431 ◽

2021 ◽

Vol 2021 ◽

pp. 1-17

Author(s):

Yang Zhao ◽

Huaxin Sun ◽

Kai Li ◽

Luxiang Shang ◽

Xiaoyan Liang ◽

...

Keyword(s):

Heart Failure ◽

Chronic Heart Failure ◽

Cardiac Fibrosis ◽

Ventricular Remodeling ◽

Left Ventricular ◽

H9c2 Cells ◽

Tnf Α ◽

Underlying Mechanisms

Background. Cholinergic anti-inflammatory pathway (CAP) is implicated in cardioprotection in chronic heart failure (CHF) by downregulating inflammation response. Mitochondrial injuries play an important role in ventricular remodeling of the CHF process. Herein, we aim to investigate whether CAP elicitation prevents ventricular remodeling in CHF by protecting myocardial mitochondrial injuries and its underlying mechanisms. Methods and Results. CHF models were established by ligation of anterior descending artery for 5 weeks. Postoperative survival rats were assigned into 5 groups: the sham group (sham, n = 10 ), CHF group (CHF, n = 11 ), Vag group (CHF+vagotomy, n = 10 ), PNU group (CHF+PNU-282987 for 4 weeks, n = 11 ), and Vag+PNU group (CHF+vagotomy+PNU-282987 for 4 weeks, n = 10 ). The antiventricular remodeling effect of cholinergic elicitation was evaluated in vivo, and H9C2 cells were selected for the TNF-α gradient stimulation experiment in vitro. In vivo, CAP agitated by PNU-282987 alleviated the left ventricular dysfunction and inhibited the energy metabolism remodeling. Further, cholinergic elicitation increased myocardium ATP levels and reduced systemic inflammation. CAP induction alleviates macrophage infiltration and cardiac fibrosis, of which the effect is counteracted by vagotomy. Myocardial mitochondrial injuries were ameliorated by CAP activation, including the reserved ultrastructural integrity, declining ROS overload, reduced myocardial apoptosis, and enhanced mitochondrial fusion. In vitro, TNF-α intervention significantly exacerbated the mitochondrial damage in H9C2 cells. Conclusion. CAP elicitation effectively improves ischemic ventricular remodeling by suppressing systemic and cardiac inflammatory response, attenuating cardiac fibrosis and potentially alleviating the mitochondrial dysfunction linked to hyperinflammation reaction.

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Cardiac fibroblasts acquire properties of matrifibrocytes in vitro and in mice with pressure overload-induced congestive heart failure

European Heart Journal ◽

10.1093/ehjci/ehaa946.3741 ◽

2020 ◽

Vol 41 (Supplement_2) ◽

Author(s):

K.M Herum ◽

G Gilles ◽

A Romaine ◽

A.O Melleby ◽

G Christensen ◽

...

Keyword(s):

Heart Failure ◽

Congestive Heart Failure ◽

Cardiac Fibroblasts ◽

Pressure Overload ◽

Left Ventricular Pressure ◽

Left Ventricular ◽

Funding Source ◽

High Stiffness

Abstract Introduction Activation of cardiac fibroblasts (CFB) is a key step in development of fibrosis in the heart. It was recently shown that, in addition to the well-studied myofibroblast (myoFB) phenotype, activated cardiac fibroblasts can adopt a newly defined matrifibrocyte phenotype, characterized by expression of extracellular matrix (ECM) genes associated with bone, cartilage and tendon development. However, it is unknown whether matrifibrocytes exists in the pressure-overloaded fibrotic and failing heart, and whether substrate stiffness drives differentiation. Hypothesis Matrifibrocyte differentiation occurs in vitro during culturing of primary cardiac fibroblasts, and in vivo in response to left ventricular pressure overload. Methods Left ventricular pressure overload induced by o-ring aortic banding (ORAB) induced cardiac phenotypes of concentric hypertrophic remodelling and congestive heart failure. Primary CFB from adult mice were cultured on plastic or soft polyacrylamide hydrogels (4.5 kPa) for various times. mRNA expression of phenotypic markers were measured by RT-PCR. Presence of smooth muscle α-actin (SMA) fibers was determined by immunocytochemistry. Results ECM genes normally expressed in bone and cartilage (COMP, CILP-2, OPG and SCX) were upregulated in hypertrophic left ventricles of mice with congestive heart failure. The myoFB marker acta2 was increased 2 weeks after ORAB, returned to baseline at 4 weeks and increased again at 20 weeks when the left ventricle was dilating and failing, indicating that the myoFB phenotype is not permanent. In vitro, primary CFB upregulated bone/cartilage-associated ECM genes after 12 days of culturing on plastic. Acta2 mRNA and SMA protein levels peaked after 9 days in culture whereafter they declined, indicating a shift in phenotype. Culturing primary CFB on soft (4.5 kPa) hydrogels delayed, but did not prevent, myoFB differentiation while expression of bone/cartilage ECM genes was absent or low, indicating that high stiffness is a driver of the matrifibrocyte phenotype. Blockers of mechanotransduction, SB431542 (TGFβRI inhibitor), Y27623 (ROCK inhibitor) and cyclosporine A (calcineurin inhibitor), completely inhibited myoFB differentiation but upregulated several matrifibrocyte markers, indicating that distinct signaling pathways regulate myoFB and matrifibrocyte differentiation. Removing inhibitors re-induced myofibroblast markers in cells on plastic but not on soft gels consistent with high stiffness promoting myofibroblast differentiation. Conclusion Primary cardiac fibroblasts acquire characteristics of matrifibrocytes in vitro when cultured for long time on plastic and in vivo in left ventricles of mice with pressure overload-induced congestive heart failure. Funding Acknowledgement Type of funding source: Public grant(s) – EU funding. Main funding source(s): Marie Sklodowska-Curie Individual Fellowship

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PLK2 is a novel regulator of osteopontin-driven fibrosis and diastolic dysfunction in permanent atrial fibrillation

European Heart Journal ◽

10.1093/ehjci/ehaa946.3671 ◽

2020 ◽

Vol 41 (Supplement_2) ◽

Author(s):

S Kuenzel ◽

E Klapproth ◽

K Kuenzel ◽

C Piorkowski ◽

M Mayr ◽

...

Keyword(s):

Heart Failure ◽

Atrial Fibrillation ◽

Diastolic Dysfunction ◽

Cardiac Fibrosis ◽

Cardiac Fibroblasts ◽

Diastolic Heart Failure ◽

Left Ventricular Diastolic Dysfunction ◽

Left Ventricular ◽

Knockout Mouse Model ◽

Ventricular Diastolic Dysfunction

Abstract Background and aim Atrial fibrillation (AF) is frequently accompanied by cardiac fibrosis and diastolic heart failure. Due to the heterogeneous nature and complexity of fibrosis, the knowledge of the underlying pathomechanisms is limited. Thus, effective antifibrotic pharmacotherapy is missing. The objective of this study was to decipher the role of polo-like kinase 2 (PLK2) in the pathogenesis of cardiac fibrosis and left ventricular diastolic dysfunction. We put particular emphasis on the identification of profibrotic downstream targets of PLK2, which can serve as therapeutic targets. Methods and results This study was based on human atrial tissue biopsies and peripheral blood samples, a PLK2 knockout mouse model, a canine tachy-pacing model and specific pharmacological interventions on cardiac fibroblasts. In human atrial AF tissue samples, PLK2 was 50% downregulated by hypoxia-induced promoter methylation compared to sinus rhythm (SR) control. Confirmatory analysis of a canine tachy-pacing model showed PLK2 downregulation exclusively in the atria but not in the ventricles. Specific pharmacological inhibition as well as genetic deletion of PLK2 led to a striking myofibroblast phenotype. Discovery proteomics revealed that the global knockout of PLK2 resulted in de novo secretion of the inflammatory cytokine osteopontin (OPN) in cardiac fibroblasts and concomitant ventricular fibrosis in the PLK2 knockout mouse model. An ELISA analysis of peripheral blood samples of AF patients with electrophysiologically proven fibrosis, confirmed significantly increased OPN plasma concentrations compared to SR and non-fibrosis AF controls. Consequently, echocardiography on PLK2 KO mice revealed left ventricular diastolic dysfunction, tachycardia and fibrosis-typical surface ECG anomalies (PQ and QRS prolongation). Mechanistically, we identified the ERK1/2 signaling pathway as the molecular link between reduced expression of PLK2 and elevated osteopontin transcription. In a reverse translational attempt, we successfully tested the capability of 5-amino-salicylic acid (5-ASA) to inhibit osteopontin transcription and to reverse a TGF-β-induced myofibroblast phenotype in vitro. Currently the long-term administration of 5-ASA is tested in PLK2 knockout mice to evaluate the therapeutic potential to prevent cardiac fibrosis and diastolic heart failure development. Conclusion and clinical impact We identified PLK2 as an epigenetically regulated kinase involved in the pathophysiology of fibrosis in AF. PLK2 knockout mice can serve as a model of diastolic heart failure wherein OPN is a promising therapeutic target. Our results strengthen the current hypothesis that atrial fibrillation is not only an ion channel disease but a complex systemic disorder. Restoration of physiological PLK2 expression and blockade of osteopontin release with 5-ASA may constitute valuable new drug targets for the prevention and treatment of fibrosis and diastolic heart failure in AF. Funding Acknowledgement Type of funding source: Public Institution(s). Main funding source(s): Faculty of Medicine, Carl Gustav Carus, Dresden, “MeDDrive Start” Grant

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Loss of Function in Dopamine D3 Receptor Attenuates Left Ventricular Cardiac Fibroblast Migration and Proliferation in vitro

Frontiers in Cardiovascular Medicine ◽

10.3389/fcvm.2021.732282 ◽

2021 ◽

Vol 8 ◽

Author(s):

Andrew Kisling ◽

Shannon Byrne ◽

Rohan U. Parekh ◽

Deepthy Melit-Thomas ◽

Lisandra E. de Castro Brás ◽

...

Keyword(s):

Cardiac Tissue ◽

Cardiac Fibroblasts ◽

Fibroblast Cell ◽

Left Ventricular ◽

Cardiac Fibroblast ◽

Loss Of Function ◽

Fibroblast Migration ◽

And Migration ◽

Proliferation And Migration

Evidence suggests the existence of an intracardiac dopaminergic system that plays a pivotal role in regulating cardiac function and fibrosis through G-protein coupled receptors, particularly mediated by dopamine receptor 3 (D3R). However, the expression of dopamine receptors in cardiac tissue and their role in cardiac fibroblast function is unclear. In this brief report, first we determined expression of D1R and D3R both in left ventricle (LV) tissue and fibroblasts. Then, we explored the role of D3R in the proliferation and migration of fibroblast cell cultures using both genetic and pharmaceutical approaches; specifically, we compared cardiac fibroblasts isolated from LV of wild type (WT) and D3R knockout (D3KO) mice in response to D3R-specific pharmacological agents. Finally, we determined if loss of D3R function could significantly alter LV fibroblast expression of collagen types I (Col1a1) and III (Col3a1). Cardiac fibroblast proliferation was attenuated in D3KO cells, mimicking the behavior of WT cardiac fibroblasts treated with D3R antagonist. In response to scratch injury, WT cardiac fibroblasts treated with the D3R agonist, pramipexole, displayed enhanced migration compared to control WT and D3KO cells. Loss of function in D3R resulted in attenuation of both proliferation and migration in response to scratch injury, and significantly increased the expression of Col3a1 in LV fibroblasts. These findings suggest that D3R may mediate cardiac fibroblast function during the wound healing response. To our knowledge this is the first report of D3R's expression and functional significance directly in mouse cardiac fibroblasts.

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Retinoid X receptor agonists attenuates cardiomyopathy in streptozotocin-induced type 1 diabetes through LKB1-dependent anti-fibrosis effects

Clinical Science ◽

10.1042/cs20190985 ◽

2020 ◽

Vol 134 (6) ◽

pp. 609-628 ◽

Cited By ~ 1

Author(s):

Dajun Chai ◽

Xiaoyan Lin ◽

Qiaowen Zheng ◽

Changsheng Xu ◽

Hong Xie ◽

...

Keyword(s):

Myocardial Fibrosis ◽

Cardiac Fibrosis ◽

Transforming Growth Factor ◽

Cardiac Fibroblasts ◽

Transforming Growth Factor Β ◽

Underlying Mechanism ◽

Left Ventricular ◽

Retinoid X Receptor ◽

Sprague Dawley

Abstract Diabetic cardiac fibrosis increases ventricular stiffness and facilitates the occurrence of diastolic dysfunction. Retinoid X receptor (RXR) plays an important role in cardiac development and has been implicated in cardiovascular diseases. In the present study, we investigated the effects of RXR agonist treatment on streptozotocin (STZ)-induced diabetic cardiomyopathy (DCM) and the underlying mechanism. Sprague–Dawley (SD) rats induced by STZ injection were treated with either RXR agonist bexarotene (Bex) or vehicle alone. Echocardiography was performed to determine cardiac structure and function. Cardiac fibroblasts (CFs) were treated with high glucose (HG) with or without the indicated concentration of Bex or the RXR ligand 9-cis-retinoic acid (9-cis-RA). The protein abundance levels were measured along with collagen, body weight (BW), blood biochemical indexes and transforming growth factor-β (TGF-β) levels. The effects of RXRα down-regulation by RXRα small interfering RNA (siRNA) were examined. The results showed that bexarotene treatment resulted in amelioration of left ventricular dysfunction by inhibiting cardiomyocyte apoptosis and myocardial fibrosis. Immunoblot with heart tissue homogenates from diabetic rats revealed that bexarotene activated liver kinase B1 (LKB1) signaling and inhibited p70 ribosomal protein S6 kinase (p70S6K). The increased collagen levels in the heart tissues of DCM rats were reduced by bexarotene treatment. Treatment of CFs with HG resulted in significantly reduced LKB1 activity and increased p70S6K activity. RXRα mediated the antagonism of 9-cis-RA on HG-induced LKB1/p70S6K activation changes in vitro. Our findings suggest that RXR agonist ameliorates STZ-induced DCM by inhibiting myocardial fibrosis via modulation of the LKB1/p70S6K signaling pathway. RXR agonists may serve as novel therapeutic agents for the treatment of DCM.

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Abstract 304: Estrogen Plays a Protective Role in Advanced Heart Failure by Suppressing Cardiac Fibrosis Associated Genes via miR129 Induction

Circulation Research ◽

10.1161/res.113.suppl_1.a304 ◽

2013 ◽

Vol 113 (suppl_1) ◽

Author(s):

Salil Sharma ◽

Andrea Iorga ◽

Harnek Singh ◽

Jingyaun Li ◽

Mansoureh Eghbali

Keyword(s):

Heart Failure ◽

Target Genes ◽

Cardiac Fibrosis ◽

Cardiac Fibroblasts ◽

Pressure Overload ◽

Neonatal Rat ◽

Fibroblast Proliferation ◽

Short Term ◽

Short Term Treatment

We have previously shown that short term treatment of estrogen(E2) can rescue advance heart failure(HF) and decreases associated fibrosis. We hypothesized that E2 can reduce fibrosis by regulating the levels of specific microRNAs including miR129-5p(miR129) through ERβ mediated mechanism. We used transaortic constriction to induce HF in male mice, and once the ejection fraction (EF) reached ~30%, one group of animals was sacrificed (HF), and the other group received 17b-estradiol via a subcutaneous pellet implant (0.012mg/pellet, n=16) (E2) for 10 days. Sham-operated mice served as CTRL. Serial echocardiography was performed to monitor cardiac structure and function. Short-term E2 treatment rescued pressure overload-induced decompensated HF in mice by restoring the EF from 33.17±1.12% to 53.05±1.29 (p <0.001, n=16). E2 decreased both interstitial and perivascular fibrosis in HF. Microarray analysis comparing HF with E2 revealed ~70 microRNAs including miR129 regulated by E2. qPCR validation revealed that E2 treatment upregulates miR129 by 2 folds compared to HF restoring it to CTRL levels. Treatment of HF with ERβ agonist (DPN), but not ERα agonist (PPT) resulted in the upregulation of miR129 indicating the E2 mediated induction of miR129 is mediated through ERβ. In vitro, angiotensin II treatment significantly downregulated miR129 expression in neonatal rat fibroblasts (NRVF) which was restored by E2 and DPN but not by E2+ERβ antagonist (PHPT) further confirming the role of ERβ in regulating miR129. In vitro, OE of miR129 in both neonatal and adult rat cardiac fibroblasts (ARVF) resulted in significant downregulation of transcripts of many in-silico predicted pro-fibrotic target genes including EGFR, RUNX, GREM1, COL2A, PDGFA, PDGFRA and the transcription factor SOX4. OE of miR129 in fibroblasts also resulted in downregulation of EGFR protein. Gain of miR129 prevented the transition of fibroblasts to myofibroblasts in both NRVF and ARVF and inhibited fibroblast proliferation in vitro. In conclusion, E2 treatment during HF induces miR129 likely through ERβ. MiR129 represses fibrosis by targeting key genes associated with cardiac fibrosis, inhibits fibroblast proliferation and fibroblast to myofibroblast transition.

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EphrinB2 Regulates Cardiac Fibrosis Through Modulating the Interaction of Stat3 and TGF-β/Smad3 Signaling

Circulation Research ◽

10.1161/circresaha.117.311045 ◽

2017 ◽

Vol 121 (6) ◽

pp. 617-627 ◽

Cited By ~ 35

Author(s):

Sheng-an Su ◽

Du Yang ◽

Yue Wu ◽

Yao Xie ◽

Wei Zhu ◽

...

Keyword(s):

Myocardial Infarction ◽

Heart Failure ◽

Cardiac Fibrosis ◽

Transforming Growth Factor ◽

Ventricular Remodeling ◽

Left Ventricular Remodeling ◽

Cardiac Fibroblasts ◽

Left Ventricular ◽

Intramyocardial Injection

Rationale: Cardiac fibrosis is a common feature in left ventricular remodeling that leads to heart failure, regardless of the cause. EphrinB2 (erythropoietin-producing hepatoma interactor B2), a pivotal bidirectional signaling molecule ubiquitously expressed in mammals, is crucial in angiogenesis during development and disease progression. Recently, EphrinB2 was reported to protect kidneys from injury-induced fibrogenesis. However, its role in cardiac fibrosis remains to be clarified. Objective: We sought to determine the role of EphrinB2 in cardiac fibrosis and the underlying mechanisms during the pathological remodeling process. Methods and Results: EphrinB2 was highly expressed in the myocardium of patients with advanced heart failure, as well as in mouse models of myocardial infarction and cardiac hypertrophy induced by angiotensin II infusion, which was accompanied by myofibroblast activation and collagen fiber deposition. In contrast, intramyocardial injection of lentiviruses carrying EphrinB2-shRNA ameliorated cardiac fibrosis and improved cardiac function in mouse model of myocardial infarction. Furthermore, in vitro studies in cultured cardiac fibroblasts demonstrated that EphrinB2 promoted the differentiation of cardiac fibroblasts into myofibroblasts in normoxic and hypoxic conditions. Mechanistically, the profibrotic effect of EphrinB2 on cardiac fibroblast was determined via activating the Stat3 (signal transducer and activator of transcription 3) and TGF-β (transforming growth factor-β)/Smad3 (mothers against decapentaplegic homolog 3) signaling. We further determined that EphrinB2 modulated the interaction between Stat3 and Smad3 and identified that the MAD homology 2 domain of Smad3 and the coil–coil domain and DNA-binding domain of Stat3 mediated the interaction. Conclusions: This study uncovered a previously unrecognized profibrotic role of EphrinB2 in cardiac fibrosis, which is achieved through the interaction of Stat3 with TGF-β/Smad3 signaling, implying a promising therapeutic target in fibrotic diseases and heart failure.

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HE4 Predicts Progressive Fibrosis and Cardiovascular Events in Patients With Dilated Cardiomyopathy

Journal of the American Heart Association ◽

10.1161/jaha.120.021069 ◽

2021 ◽

Author(s):

Masahiro Yamamoto ◽

Shinsuke Hanatani ◽

Satoshi Araki ◽

Yasuhiro Izumiya ◽

Toshihiro Yamada ◽

...

Keyword(s):

Dilated Cardiomyopathy ◽

Cardiac Fibrosis ◽

Interstitial Fibrosis ◽

Cox Model ◽

Cardiac Fibroblasts ◽

Left Ventricular ◽

Extracellular Signal Regulated Kinase ◽

Extracellular Signal

Background Cardiac fibrosis plays a crucial role in the pathogenesis of dilated cardiomyopathy (DCM). HE4 (human epididymis protein 4) is a secretory protein expressed in activated fibroblasts that exacerbates tissue fibrosis. In the present study, we investigated the clinical utility of HE4 measurement in patients with DCM and its pathophysiological role in preclinical experiments in vivo and in vitro. Methods and Results We measured serum HE4 levels of 87 patients with DCM. Endomyocardial biopsy expressed severe fibrosis only in the high HE4 group ( P <0.0001). Echocardiography showed that left ventricular end‐diastolic diameter tends to decrease over time (58±7.3 to 51±6.6 mm; P <0.0001) in the low HE4 group (<59.65 pmol/L [median value]). HE4 was significantly associated with risk reduction of mortality and cardiovascular hospitalization in multivariate Cox model. In vivo, HE4 was highly expressed in kidney and lung tissue of mouse, and scarcely expressed in heart. In genetically induced DCM mouse model, HE4 expression increased in kidney but not in heart and lung. In vitro, supernatant from HE4‐transfected human embryonic kidney 293T cells enhanced transdifferentiation of rat neonatal fibroblasts and increased expression of fibrosis‐related genes, and this was accompanied by the activation of extracellular signal‐regulated kinase signaling in cardiac fibroblasts. Treatment with an inhibitor of upstream signal of extracellular signal‐regulated kinase or a neutralizing HE4 antibody canceled the profibrotic properties of HE4. Conclusions HE4 functions as a secretory factor, activating cardiac fibroblasts, thereby inducing cardiac interstitial fibrosis. HE4 could be a promising biomarker for assessing ongoing fibrosis and a novel therapeutic target in DCM. Registration URL: https://upload.umin.ac.jp/cgi‐open‐bin/ctr ; Unique identifier: UMIN000043062.

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