A miR-208–Mef2 Axis Drives the Decompensation of Right Ventricular Function in Pulmonary Hypertension

Rationale: Right ventricular (RV) failure is a major cause of morbidity and mortality in pulmonary hypertension, but its mechanism remains unknown. Myocyte enhancer factor 2 (Mef2) has been implicated in RV development, regulating metabolic, contractile, and angiogenic genes. Moreover, Mef2 regulates microRNAs that have emerged as important determinants of cardiac development and disease, but for which the role in RV is still unclear. Objective: We hypothesized a critical role of a Mef2-microRNAs axis in RV failure. Methods and Results: In a rat pulmonary hypertension model (monocrotaline), we studied RV free wall tissues from rats with normal, compensated, and decompensated RV hypertrophy, carefully defined based on clinically relevant parameters, including RV systolic and end-diastolic pressures, cardiac output, RV size, and morbidity. Mef2c expression was sharply increased in compensating phase of RVH tissues but was lost in decompensation phase of RVH. An unbiased screening of microRNAs in our model resulted to a short microRNA signature of decompensated RV failure, which included the myocardium-specific miR-208, which was progressively downregulated as RV failure progressed, in contrast to what is described in left ventricular failure. With mechanistic in vitro experiments using neonatal and adult RV cardiomyocytes, we showed that miR-208 inhibition, as well as tumor necrosis factor-&agr;, activates the complex mediator of transcription 13/nuclear receptor corepressor 1 axis, which in turn promotes Mef2 inhibition, closing a self-limiting feedback loop, driving the transition from compensating phase of RVH toward decompensation phase of RVH. In our model, serum tumor necrosis factor-&agr; levels progressively increased with time while serum miR-208 levels decreased, mirroring its levels in RV myocardium. Conclusions: We describe an RV-specific mechanism for heart failure, which could potentially lead to new biomarkers and therapeutic targets.

[1]  W. Fang,et al.  Comparison of 18F-FDG uptake by right ventricular myocardium in idiopathic pulmonary arterial hypertension and pulmonary arterial hypertension associated with congenital heart disease , 2012, Pulmonary circulation.

[2]  N. Voelkel,et al.  Suppression of histone deacetylases worsens right ventricular dysfunction after pulmonary artery banding in rats. , 2011, American journal of respiratory and critical care medicine.

[3]  B. Black,et al.  Transcriptional control of muscle development by myocyte enhancer factor-2 (MEF2) proteins. , 1998, Annual review of cell and developmental biology.

[4]  S. Guruswamy,et al.  Myocyte enhancer factor 2 (MEF2)-binding site is required for GLUT4 gene expression in transgenic mice. Regulation of MEF2 DNA binding activity in insulin-deficient diabetes. , 1998, The Journal of biological chemistry.

[5]  T. O’Connell,et al.  Isolation and culture of adult mouse cardiac myocytes. , 2007, Methods in molecular biology.

[6]  Antonio Abbate,et al.  Mechanisms of right heart failure—A work in progress and a plea for failure prevention , 2013, Pulmonary circulation.

[7]  Federica Limana,et al.  Circulating microRNAs are new and sensitive biomarkers of myocardial infarction , 2010, European heart journal.

[8]  Kohtaro Abe,et al.  The right ventricle under pressure: cellular and molecular mechanisms of right-heart failure in pulmonary hypertension. , 2009, Chest.

[9]  N. Voelkel,et al.  Alveolar inflammation and arachidonate metabolism in monocrotaline-induced pulmonary hypertension. , 1985, The American journal of physiology.

[10]  Brad T. Sherman,et al.  Systematic and integrative analysis of large gene lists using DAVID bioinformatics resources , 2008, Nature Protocols.

[11]  E. Olson,et al.  Therapeutic Inhibition of miR-208a Improves Cardiac Function and Survival During Heart Failure , 2011, Circulation.

[12]  P. Fawcett,et al.  Molecular signature of a right heart failure program in chronic severe pulmonary hypertension. , 2011, American journal of respiratory cell and molecular biology.

[13]  D. Bernstein,et al.  Dynamic microRNA expression during the transition from right ventricular hypertrophy to failure. , 2012, Physiological genomics.

[14]  S. Berger,et al.  A Feed-Forward Repression Mechanism Anchors the Sin3/Histone Deacetylase and N-CoR/SMRT Corepressors on Chromatin , 2006, Molecular and Cellular Biology.

[15]  M. Privalsky,et al.  The role of corepressors in transcriptional regulation by nuclear hormone receptors. , 2004, Annual review of physiology.

[16]  N. Bodyak,et al.  Deletion of Ptpn11 (Shp2) in Cardiomyocytes Causes Dilated Cardiomyopathy via Effects on the Extracellular Signal–Regulated Kinase/Mitogen-Activated Protein Kinase and RhoA Signaling Pathways , 2008, Circulation.

[17]  B. Groves,et al.  Changes in gene expression in the intact human heart. Downregulation of alpha-myosin heavy chain in hypertrophied, failing ventricular myocardium. , 1997, The Journal of clinical investigation.

[18]  E. Olson,et al.  An intragenic MEF2-dependent enhancer directs muscle-specific expression of microRNAs 1 and 133 , 2007, Proceedings of the National Academy of Sciences.

[19]  F. Charron,et al.  GATA‐dependent recruitment of MEF2 proteins to target promoters , 2000, The EMBO journal.

[20]  D. Wilson,et al.  Progressive inflammatory and structural changes in the pulmonary vasculature of monocrotaline-treated rats. , 1989, Microvascular research.

[21]  J. Sandoval,et al.  Right ventricular ischemia in patients with primary pulmonary hypertension. , 2001, Journal of the American College of Cardiology.

[22]  S. Archer,et al.  Therapeutic inhibition of fatty acid oxidation in right ventricular hypertrophy: exploiting Randle’s cycle , 2011, Journal of Molecular Medicine.

[23]  P. Doevendans,et al.  Early assessment of acute coronary syndromes in the emergency department: the potential diagnostic value of circulating microRNAs , 2012, EMBO molecular medicine.

[24]  Yong Zhao,et al.  Serum response factor regulates a muscle-specific microRNA that targets Hand2 during cardiogenesis , 2005, Nature.

[25]  A. Waggoner,et al.  Severe pulmonary hypertension without right ventricular failure: the unique hearts of patients with Eisenmenger syndrome. , 2002, The American journal of cardiology.

[26]  S. Hunt,et al.  Right Ventricular Function in Cardiovascular Disease, Part II: Pathophysiology, Clinical Importance, and Management of Right Ventricular Failure , 2008, Circulation.

[27]  D. Metzger,et al.  Skeletal muscle mitochondrial dysfunction precedes right ventricular impairment in experimental pulmonary hypertension , 2012, Molecular and Cellular Biochemistry.

[28]  C. Drake,et al.  The transcription factor MEF2C-null mouse exhibits complex vascular malformations and reduced cardiac expression of angiopoietin 1 and VEGF. , 1999, Developmental biology.

[29]  Xiaoxia Qi,et al.  Control of Stress-Dependent Cardiac Growth and Gene Expression by a MicroRNA , 2007, Science.

[30]  P. Jones,et al.  N-CoR-HDAC corepressor complexes: roles in transcriptional regulation by nuclear hormone receptors. , 2003, Current topics in microbiology and immunology.

[31]  I. Haber,et al.  The inhibition of pyruvate dehydrogenase kinase improves impaired cardiac function and electrical remodeling in two models of right ventricular hypertrophy: resuscitating the hibernating right ventricle , 2009, Journal of Molecular Medicine.

[32]  R. Testa,et al.  Diagnostic potential of circulating miR-499-5p in elderly patients with acute non ST-elevation myocardial infarction. , 2013, International journal of cardiology.

[33]  S. Chien,et al.  Cardiac developmental defects and eccentric right ventricular hypertrophy in cardiomyocyte focal adhesion kinase (FAK) conditional knockout mice , 2008, Proceedings of the National Academy of Sciences.

[34]  E. Dodou,et al.  Mef 2 c is a direct transcriptional target of ISL 1 and GATA factors in the anterior heart field during mouse embryonic development , 2022 .

[35]  M. Maitland,et al.  Inflammation, growth factors, and pulmonary vascular remodeling. , 2009, Journal of the American College of Cardiology.

[36]  M. S. Mcmurtry,et al.  Pyruvate dehydrogenase inhibition by the inflammatory cytokine TNFα contributes to the pathogenesis of pulmonary arterial hypertension , 2011, Journal of Molecular Medicine.

[37]  C. Long,et al.  Chronic Pulmonary Artery Pressure Elevation Is Insufficient to Explain Right Heart Failure , 2009, Circulation.

[38]  S J Allen,et al.  Left ventricular myocardial edema. Lymph flow, interstitial fibrosis, and cardiac function. , 1991, Circulation research.

[39]  B. Black,et al.  Mitochondrial deficiency and cardiac sudden death in mice lacking the MEF2A transcription factor , 2002, Nature Medicine.

[40]  M. Lazar,et al.  The histone‐binding code of nuclear receptor co‐repressors matches the substrate specificity of histone deacetylase 3 , 2005, EMBO reports.

[41]  Deepak Srivastava,et al.  A genetic blueprint for cardiac development , 2000, Nature.

[42]  M. Satoh,et al.  A cellular microRNA, let-7i, is a novel biomarker for clinical outcome in patients with dilated cardiomyopathy. , 2011, Journal of cardiac failure.

[43]  R. Conaway,et al.  Function and regulation of the Mediator complex. , 2011, Current opinion in genetics & development.

[44]  E. Dodou,et al.  Mef2c is a direct transcriptional target of ISL1 and GATA factors in the anterior heart field during mouse embryonic development , 2004, Development.

[45]  R. Trembath,et al.  Elevated Levels of Inflammatory Cytokines Predict Survival in Idiopathic and Familial Pulmonary Arterial Hypertension , 2010, Circulation.

[46]  Sotirios D. Zervopoulos,et al.  A metabolic remodeling in right ventricular hypertrophy is associated with decreased angiogenesis and a transition from a compensated to a decompensated state in pulmonary hypertension , 2013, Journal of Molecular Medicine.

[47]  M. A. Saad,et al.  Early Activation of the Multicomponent Signaling Complex Associated With Focal Adhesion Kinase Induced by Pressure Overload in the Rat Heart , 2000, Circulation research.

[48]  Yue Li,et al.  Circulating microRNA: a novel potential biomarker for early diagnosis of acute myocardial infarction in humans. , 2010, European heart journal.

[49]  R. Roeder,et al.  Dynamic regulation of pol II transcription by the mammalian Mediator complex. , 2005, Trends in biochemical sciences.

[50]  L. Leinwand,et al.  The cell biology of disease Cellular mechanisms of cardiomyopathy , 2022 .

[51]  Hyung-Seok Kim,et al.  Sodium valproate, a histone deacetylase inhibitor, but not captopril, prevents right ventricular hypertrophy in rats. , 2010, Circulation journal : official journal of the Japanese Circulation Society.

[52]  Jian-Fu Chen,et al.  MicroRNA-208a is a regulator of cardiac hypertrophy and conduction in mice. , 2009, The Journal of clinical investigation.

[53]  Evan G. Williams,et al.  NCoR1 Is a Conserved Physiological Modulator of Muscle Mass and Oxidative Function , 2011, Cell.

[54]  J. Dyck,et al.  A dynamic and chamber-specific mitochondrial remodeling in right ventricular hypertrophy can be therapeutically targeted. , 2008, The Journal of thoracic and cardiovascular surgery.

[55]  Chad E. Grueter,et al.  A Cardiac MicroRNA Governs Systemic Energy Homeostasis by Regulation of MED13 , 2012, Cell.

[56]  P. Anversa,et al.  Angiotensin II stimulation in vitro induces hypertrophy of normal and postinfarcted ventricular myocytes. , 1998, Circulation research.

[57]  J. Bauersachs,et al.  Diagnostic and prognostic impact of six circulating microRNAs in acute coronary syndrome. , 2011, Journal of molecular and cellular cardiology.

[58]  Nico Westerhof,et al.  Progressive right ventricular dysfunction in patients with pulmonary arterial hypertension responding to therapy. , 2011, Journal of the American College of Cardiology.