Medicine and Health Sciences Commons^™

Reversing Heart Failure With A Ventricular Anchoring Device: Another Hope For Myopathic Mitral Regurgitation., J. Eduardo Rame

Center for Translational Medicine Faculty Papers

No abstract provided.

Mechanisms Of Simvastatin Myotoxicity: The Role Of Autophagy Flux Inhibition., Arya Emami, Shahla Shojaei, Simone C. Da Silva Rosa, Mahmoud Aghaei, Ehsan Samiei, Amir Reza Vosoughi, Forouh Kalantari, Philip Kawalec, James Thliveris, Pawan Sharma, Amir A. Zeki, Mohsen Akbari, Joseph W. Gordon, Saeid Ghavami

Center for Translational Medicine Faculty Papers

Statins are some of the most widely used drugs worldwide, but one of their major side effects is myotoxicity. Using mouse myoblast (C2C12) and human alveolar rhabdomyosarcoma cell lines (RH30) in both 2-dimensional (2D) and 3-dimensional (3D) cell culture, we investigated the mechanisms of simvastatin's myotoxicity. We found that simvastatin significantly reduced cell viability in C2C12 cells compared to RH30 cells. However, simvastatin induced greater apoptosis in RH30 compared to C2C12 cells. Simvastatin-induced cell death is dependent on geranylgeranyl pyrophosphate (GGPP) in C2C12 cells, while in RH30 cells it is dependent on both farnesyl pyrophosphate (FPP) and GGPP. Simvastatin inhibited …

C1q/Tnf-Related Protein 3 (Ctrp3) And 9 (Ctrp9) Concentrations Are Decreased In Patients With Heart Failure And Are Associated With Increased Morbidity And Mortality., Chao Gao, Shasha Zhao, Kun Lian, Baibing Mi, Rui Si, Zhijun Tan, Feng Fu, Shuai Wang, Rutao Wang, Xin-Liang Ma, Ling Tao

Center for Translational Medicine Faculty Papers

BACKGROUND: Biochemical marker has revolutionized the approach to the diagnosis of heart failure. However, it remains difficult to assess stability of the patient. As such, novel means of stratifying disease severity are needed. C1q/TNF-Related Protein 3 (CTRP3) and C1q/TNF-Related Protein 9 (CTRP9) are novel adipokines that contribute to energy homeostasis with additional anti-inflammatory and anti-ischemic properties. The aim of our study is to evaluate concentrations of CTRP3 and CTRP9 in patients with HFrEF (heart failure with reduced ejection fraction) and whether associated with mortality.

METHODS: Clinical data and plasma were obtained from 176 healthy controls and 168 patients with HFrEF. …

Transcriptional Up-Regulation Of Relaxin-3 By Nur77 Attenuates Β-Adrenergic Agonist-Induced Apoptosis In Cardiomyocytes., Xiaohua You, Zhifu Guo, Fang Cheng, Bing Yi, Fan Yang, Xinzhu Liu, Ni Zhu, Xianxian Zhao, Guijun Yan, Xin-Liang Ma, Jianxin Sun

Center for Translational Medicine Faculty Papers

The relaxin family peptides have been shown to exert several beneficial effects on the heart, including anti-apoptosis, anti-fibrosis, and anti-hypertrophy activity. Understanding their regulation might provide new opportunities for therapeutic interventions, but the molecular mechanism(s) coordinating relaxin expression in the heart remain largely obscured. Previous work demonstrated a role for the orphan nuclear receptor Nur77 in regulating cardiomyocyte apoptosis. We therefore investigated Nur77 in the hopes of identifying novel relaxin regulators. Quantitative real-time PCR (qRT-PCR) and enzyme-linked immunosorbent assay (ELISA) data indicated that ectopic expression of orphan nuclear receptor Nur77 markedly increased the expression of latexin-3 (RLN3), but not relaxin-1 …

Hmgcs2 Is A Key Ketogenic Enzyme Potentially Involved In Type 1 Diabetes With High Cardiovascular Risk., Sanket Kumar Shukla, Weijing Liu, Kunal Sikder, Sankar Addya, Amrita Sarkar, Yidong Wei, Khadija Rafiq

Center for Translational Medicine Faculty Papers

Diabetes increases the risk of Cardio-vascular disease (CVD). CVD is more prevalent in type 2 diabetes (T2D) than type 1 diabetes (T1D), but the mortality risk is higher in T1D than in T2D. The pathophysiology of CVD in T1D is poorly defined. To learn more about biological pathways that are potentially involved in T1D with cardiac dysfunction, we sought to identify differentially expressed genes in the T1D heart. Our study used T1D mice with severe hyperglycemia along with significant deficits in echocardiographic measurements. Microarray analysis of heart tissue RNA revealed that the T1D mice differentially expressed 10 genes compared to …

Determining The Absolute Requirement Of G Protein-Coupled Receptor Kinase 5 For Pathological Cardiac Hypertrophy: Short Communication., Jessica I Gold, Erhe Gao, Xiying Shang, Richard T Premont, Walter J Koch

Center for Translational Medicine Faculty Papers

RATIONALE: Heart failure (HF) is often the end phase of maladaptive cardiac hypertrophy. A contributing factor is activation of a hypertrophic gene expression program controlled by decreased class II histone deacetylase (HDAC) transcriptional repression via HDAC phosphorylation. Cardiac-specific overexpression of G proteinen-coupled receptor kinase-5 (GRK5) has previously been shown to possess nuclear activity as a HDAC5 kinase, promoting an intolerance to in vivo ventricular pressure overload; however, its endogenous requirement in adaptive and maladaptive hypertrophy remains unknown.

OBJECTIVE: We used mouse models with global or cardiomyocyte-specific GRK5 gene deletion to determine the absolute requirement of endogenous GRK5 for cardiac hypertrophy …

Cardiac G-Protein-Coupled Receptor Kinase 2 Ablation Induces A Novel Ca2+ Handling Phenotype Resistant To Adverse Alterations And Remodeling After Myocardial Infarction., Philip W Raake, Xiaoying Zhang, Leif E Vinge, Henriette Brinks, Erhe Gao, Naser Jaleel, Yingxin Li, Mingxin Tang, Patrick Most, Gerald W Dorn, Steven R Houser, Hugo A Katus, Xiongwen Chen, Walter J Koch

Center for Translational Medicine Faculty Papers

BACKGROUND: G-protein-coupled receptor kinase 2 (GRK2) is a primary regulator of β-adrenergic signaling in the heart. G-protein-coupled receptor kinase 2 ablation impedes heart failure development, but elucidation of the cellular mechanisms has not been achieved, and such elucidation is the aim of this study.

METHODS AND RESULTS: Myocyte contractility, Ca(2+) handling and excitation-contraction coupling were studied in isolated cardiomyocytes from wild-type and GRK2 knockout (GRK2KO) mice without (sham) or with myocardial infarction (MI). In cardiac myocytes isolated from unstressed wild-type and GRK2KO hearts, myocyte contractions and Ca(2+) transients were similar, but GRK2KO myocytes had lower sarcoplasmic reticulum (SR) Ca(2+) content …

Cardioprotection Of Controlled And Cardiac-Specific Over-Expression Of A(2a)-Adenosine Receptor In The Pressure Overload., Eman A Hamad, Weizhong Zhu, Tung O Chan, Valerie Myers, Erhe Gao, Xue Li, Jin Zhang, Jianliang Song, Xue-Qian Zhang, Joseph Y Cheung, Walter Koch, Arthur M Feldman

Center for Translational Medicine Faculty Papers

Adenosine binds to three G protein-coupled receptors (R) located on the cardiomyocyte (A(1)-R, A(2A)-R and A(3)-R) and provides cardiac protection during both ischemic and load-induced stress. While the role of adenosine receptor-subtypes has been well defined in the setting of ischemia-reperfusion, far less is known regarding their roles in protecting the heart during other forms of cardiac stress. Because of its ability to increase cardiac contractility and heart rate, we hypothesized that enhanced signaling through A(2A)-R would protect the heart during the stress of transverse aortic constriction (TAC). Using a cardiac-specific and inducible promoter, we selectively over-expressed A(2A)-R in FVB …

Microrna-145 Protects Cardiomyocytes Against Hydrogen Peroxide (H₂O₂)-Induced Apoptosis Through Targeting The Mitochondria Apoptotic Pathway., Ruotian Li, Guijun Yan, Qiaoling Li, Haixiang Sun, Yali Hu, Jianxin Sun, Biao Xu

Center for Translational Medicine Faculty Papers

MicroRNAs, a class of small and non-encoding RNAs that transcriptionally or post-transcriptionally modulate the expression of their target genes, has been implicated as critical regulatory molecules in many cardiovascular diseases, including ischemia/reperfusion induced cardiac injury. Here, we report microRNA-145, a tumor suppressor miRNA, can protect cardiomyocytes from hydrogen peroxide H₂O₂-induced apoptosis through targeting the mitochondrial pathway. Quantitative real-time PCR (qPCR) demonstrated that the expression of miR-145 in either ischemia/reperfused mice myocardial tissues or H₂O₂-treated neonatal rat ventricle myocytes (NRVMs) was markedly down-regulated. Over-expression of miR-145 significantly inhibited the H₂O₂-induced cellular apoptosis, ROS production, mitochondrial structure disruption as well as the …

Orphan Nuclear Receptor Nur77 Regulates Androgen Receptor Gene Expression In Mouse Ovary., Anyi Dai, Guijun Yan, Qinyuan He, Yue Jiang, Qun Zhang, Ting Fang, Lijun Ding, Jianxin Sun, Haixiang Sun, Yali Hu

Center for Translational Medicine Faculty Papers

The androgen receptor (AR) is a nuclear receptor that is expressed in growing follicles and involved in folliculogenesis and follicle growth. The orphan nuclear receptor, Nur77, also has an important role in steroid signaling and follicle maturation. We hypothesized that AR levels and androgen signaling through AR are regulated by Nur77 in the ovary. In the ovaries of Nur77 knockout mice (n = 5), real-time PCR results showed that the mRNA levels of AR and an androgen signaling target gene, Kitl, were decreased by 35% and 24%, respectively, relative to wild-type mice (n = 5), which suggested transcriptional regulation of …

Wnt Signaling Exerts An Antiproliferative Effect On Adult Cardiac Progenitor Cells Through Igfbp3., Angelos Oikonomopoulos, Konstantina-Ioanna Sereti, Frank Conyers, Michael Bauer, Annette Liao, Jian Guan, Dylan Crapps, Jung-Kyu Han, Hanhua Dong, Ahmad F Bayomy, Gabriel C Fine, Karen Westerman, Travis L Biechele, Randall T Moon, Thomas Force, Ronglih Liao

Center for Translational Medicine Faculty Papers

RATIONALE: Recent work in animal models and humans has demonstrated the presence of organ-specific progenitor cells required for the regenerative capacity of the adult heart. In response to tissue injury, progenitor cells differentiate into specialized cells, while their numbers are maintained through mechanisms of self-renewal. The molecular cues that dictate the self-renewal of adult progenitor cells in the heart, however, remain unclear.

OBJECTIVE: We investigate the role of canonical Wnt signaling on adult cardiac side population (CSP) cells under physiological and disease conditions.

METHODS AND RESULTS: CSP cells isolated from C57BL/6J mice were used to study the effects of canonical …

Adrenal Beta-Arrestin 1 Inhibition In Vivo Attenuates Post-Myocardial Infarction Progression To Heart Failure And Adverse Remodeling Via Reduction Of Circulating Aldosterone Levels, Anastasios Lymperopoulos, Phd, Giuseppe Rengo, Md, Carmela Zincarelli, Md, Jihee Kim, Phd, Walter J. Koch, Phd

Center for Translational Medicine Faculty Papers

ABSTRACT

OBJECTIVES: We investigated whether adrenal betaarrestin 1 (betaarr1)-mediated aldosterone production plays any role in post-MI HF progression.

BACKGROUND: Heart failure (HF) represents one of the most significant health problems worldwide and new and innovative treatments are needed. Aldosterone contributes significantly to HF progression after myocardial infarction (MI) by accelerating adverse cardiac remodeling and ventricular dysfunction. It is produced by the adrenal cortex after angiotensin II (AngII) activation of AngII type 1 receptors (AT1Rs), G protein-coupled receptors (GPCRs) that also signal independently of G proteins. G protein-independent signaling is mediated by betaarrestin (betaarr) -1 and -2. We recently reported that …

Research Priorities In Hypertrophic Cardiomyopathy: Report Of A Working Group Of The National Heart, Lung, And Blood Institute., Thomas Force, Robert O Bonow, Steven R Houser, R John Solaro, Ray E Hershberger, Bishow Adhikari, Mark E Anderson, Robin Boineau, Barry J Byrne, Thomas P Cappola, Raghu Kalluri, Martin M Lewinter, Martin S Maron, Jeffery D Molkentin, Steve R Ommen, Michael Regnier, W H Wilson Tang, Rong Tian, Marvin A Konstam, Barry J Maron, Christine E Seidman

Center for Translational Medicine Faculty Papers

Hypertrophic cardiomyopathy (HCM) is a myocardial disorder characterized by left ventricular (LV) hypertrophy without dilatation and without apparent cause (ie, it occurs in the absence of severe hypertension, aortic stenosis, or other cardiac or systemic diseases that might cause LV hypertrophy). Numerous excellent reviews and consensus documents provide a wealth of additional background.1–8 HCM is the leading cause of sudden death in young people and leads to significant disability in survivors. It is caused by mutations in genes that encode components of the sarcomere. Cardiomyocyte and cardiac hypertrophy, myocyte disarray, interstitial and replacement fibrosis, and dysplastic intramyocardial arterioles characterize the …

Phospholemman: A Novel Cardiac Stress Protein., Joseph Y Cheung, Xue-Qian Zhang, Jianliang Song, Erhe Gao, Joseph E Rabinowitz, Tung O Chan, Jufang Wang

Center for Translational Medicine Faculty Papers

Phospholemman (PLM), a member of the FXYD family of regulators of ion transport, is a major sarcolemmal substrate for protein kinases A and C in cardiac and skeletal muscle. In the heart, PLM co-localizes and co-immunoprecipitates with Na(+)-K(+)-ATPase, Na(+)/Ca(2+) exchanger, and L-type Ca(2+) channel. Functionally, when phosphorylated at serine(68), PLM stimulates Na(+)-K(+)-ATPase but inhibits Na(+)/Ca(2+) exchanger in cardiac myocytes. In heterologous expression systems, PLM modulates the gating of cardiac L-type Ca(2+) channel. Therefore, PLM occupies a key modulatory role in intracellular Na(+) and Ca(2+) homeostasis and is intimately involved in regulation of excitation-contraction (EC) coupling. Genetic ablation of PLM results …

Gsk-3alpha Directly Regulates Beta-Adrenergic Signaling And The Response Of The Heart To Hemodynamic Stress In Mice., Jibin Zhou, Hind Lal, Xiongwen Chen, Xiying Shang, Jianliang Song, Yingxin Li, Risto Kerkela, Bradley W Doble, Katrina Macaulay, Morgan Decaul, Walter J Koch, John Farber, James Woodgett, Erhe Gao, Thomas Force

Center for Translational Medicine Faculty Papers

The glycogen synthase kinase-3 (GSK-3) family of serine/threonine kinases consists of 2 highly related isoforms, alpha and beta. Although GSK-3beta has an important role in cardiac development, much remains unknown about the function of either GSK-3 isoform in the postnatal heart. Herein, we present what we believe to be the first studies defining the role of GSK-3alpha in the mouse heart using gene targeting. Gsk3a(-/-) mice over 2 months of age developed progressive cardiomyocyte and cardiac hypertrophy and contractile dysfunction. Following thoracic aortic constriction in young mice, we observed enhanced hypertrophy that rapidly transitioned to ventricular dilatation and contractile dysfunction. …

An Adrenal Beta-Arrestin 1-Mediated Signaling Pathway Underlies Angiotensin Ii-Induced Aldosterone Production In Vitro And In Vivo., Anastasios Lymperopoulos, Giuseppe Rengo, Carmela Zincarelli, Jihee Kim, Stephen Soltys, Walter J Koch

Center for Translational Medicine Faculty Papers

Aldosterone produces a multitude of effects in vivo, including promotion of postmyocardial infarction adverse cardiac remodeling and heart failure progression. It is produced and secreted by the adrenocortical zona glomerulosa (AZG) cells after angiotensin II (AngII) activation of AngII type 1 receptors (AT(1)Rs). Until now, the general consensus for AngII signaling to aldosterone production has been that it proceeds via activation of G(q/11)-proteins, to which the AT(1)R normally couples. Here, we describe a novel signaling pathway underlying this AT(1)R-dependent aldosterone production mediated by beta-arrestin-1 (betaarr1), a universal heptahelical receptor adapter/scaffolding protein. This pathway results in sustained ERK activation and subsequent …

Deletion Of Gsk-3beta In Mice Leads To Hypertrophic Cardiomyopathy Secondary To Cardiomyoblast Hyperproliferation., Risto Kerkela, Lisa Kockeritz, Katrina Macaulay, Jibin Zhou, Bradley W. Doble, Cara Beahm, Sarah Greytak, Kathleen Woulfe, Chinmay M. Trivedi, James R. Woodgett, Jonathan A. Epstein, Thomas Force, Gordon S. Huggins

Center for Translational Medicine Faculty Papers

Based on extensive preclinical data, glycogen synthase kinase-3 (GSK-3) has been proposed to be a viable drug target for a wide variety of disease states, ranging from diabetes to bipolar disorder. Since these new drugs, which will be more powerful GSK-3 inhibitors than lithium, may potentially be given to women of childbearing potential, and since it has controversially been suggested that lithium therapy might be linked to congenital cardiac defects, we asked whether GSK-3 family members are required for normal heart development in mice. We report that terminal cardiomyocyte differentiation was substantially blunted in Gsk3b(-/-) embryoid bodies. While GSK-3alpha-deficient mice …

Beta Blocker Specificity: A Building Block Toward Personalized Medicine., Brent R Degeorge, Walter J Koch

Center for Translational Medicine Faculty Papers

Drugs known as beta blockers, which antagonize the beta-adrenergic receptor (beta-AR), are an important component of the treatment regimen for chronic heart failure (HF). However, a significant body of evidence indicates that genetic heterogeneity at the level of the beta(1)-AR may be a factor in explaining the variable responses of HF patients to beta blockade. In this issue of the JCI, Rochais et al. describe how a single amino acid change in beta(1)-AR alters its structural conformation and improves its functional response to carvedilol, a beta blocker currently used in the treatment of HF (see the related article beginning on …

P5l Mutation In Ank Results In An Increase In Extracellular Inorganic Pyrophosphate During Proliferation And Nonmineralizing Hypertrophy In Stably Transduced Atdc5 Cells, Raihana Zaka, David Stokes, Arnold S. Dion, Anna Kusnierz, Fei Han, Charlene J. Williams

Center for Translational Medicine Faculty Papers

Ank is a multipass transmembrane protein that regulates the cellular transport of inorganic pyrophosphate. In the progressive ankylosis (ank) mouse, a premature termination mutation at glutamic acid 440 results in a phenotype characterized by inappropriate deposition of basic calcium phosphate crystals in skeletal tissues. Mutations in the amino terminus of ANKH, the human homolog of Ank, result in familial calcium pyrophosphate dihydrate deposition disease. It has been hypothesized that these mutations result in a gain-of-function with respect to the elaboration of extracellular inorganic pyrophosphate. To explore this issue in a mineralization-competent system, we stably transduced ATDC5 cells with wild-type Ank …