Medicine and Health Sciences Commons^™

Circulating Micrornas In Cardiovascular Disease, David Mcmanus, Victor Ambros

Victor R. Ambros

Comment on: Transcoronary concentration gradients of circulating microRNAs. [Circulation. 2011]

Circulating Micrornas Are Associated With Paroxysmal Or Persistent Atrial Fibrillation, David D. Mcmanus, Jeanine Ward, Amir Y. Shaikh, Khushleen Jaggi, Victor R. Ambros, Jane Freedman, John F. Keaney Jr.

Victor R. Ambros

Introduction: Novel methods of identifying individuals at risk for atrial fibrillation (AF) are needed. MicroRNAs (MiRNAs) regulate gene expression in a number of cardiovascular diseases, including AF. It is unknown, however, if key circulating, cardiac-specific miRNAs differ between individuals with paroxysmal or persistent AF and those in sinus rhythm. Methods: 17 individuals with a history of AF were recruited prior to catheter ablation. 24 hospitalized patients in normal sinus rhythm and no history of AF comprised the control group. 94 plasma miRNAs were selected based on a priori associations with processes implicated in AF for evaluation using the TaqMan miRNA …

Circulating Cell And Plasma Microrna Profiles Differ Between Non-St-Segment And St-Segment-Elevation Myocardial Infarction, Jeanine Ward, Nada Esa, Rahul Pidikiti, Jane E. Freedman, John F. Keaney, Kahraman Tanriverdi, Olga Vitseva, Victor R. Ambros, Rosalind Lee, David D. Mcmanus

Victor R. Ambros

BACKGROUND: Differences in plasma and whole blood expression microRNAs (miRNAs) in patients with an acute coronary syndrome (ACS) have been determined in both in vitro and in vivo studies. Although most circulating miRNAs are located in the cellular components of whole blood, little is known about the miRNA profiles of whole blood subcomponents, including plasma, platelets and leukocytes in patients with myocardial ischemia. METHODS: Thirteen patients with a ST-segment-elevation (STEMI) or non-ST-segment elevation (NSTEMI) myocardial infarction were identified in the University of Massachusetts Medical Center Emergency Department (ED) or cardiac catheterization laboratory between February and June of 2012. Whole blood …

Crosstalk Between Brca-Fanconi Anemia And Mismatch Repair Pathways Prevents Msh2-Dependent Aberrant Dna Damage Responses, Min Peng, Jenny X. Xie, Anna J. Ucher, Janet Stavnezer, Sharon B. Cantor

Janet M. Stavnezer

Several proteins in the BRCA-Fanconi anemia (FA) pathway, such as FANCJ, BRCA1, and FANCD2, interact with mismatch repair (MMR) pathway factors, but the significance of this link remains unknown. Unlike the BRCA-FA pathway, the MMR pathway is not essential for cells to survive toxic DNA interstrand crosslinks (ICLs), although MMR proteins bind ICLs and other DNA structures that form at stalled replication forks. We hypothesized that MMR proteins corrupt ICL repair in cells that lack crosstalk between BRCA-FA and MMR pathways. Here, we show that ICL sensitivity of cells lacking the interaction between FANCJ and the MMR protein MLH1 is …

Increased Ho-1 Levels Ameliorate Fatty Liver Development Through A Reduction Of Heme And Recruitment Of Fgf21, Terry Hinds, Komal Sodhi, Charles Meadows, Nader Abraham, Larisa Fedorova, Nitin Puri, Dong Kim, Stephen Peterson, Joseph Shapiro, Attallah Kappas

Charles Meadows

Objective Obese leptin deficient (ob/ob) mice are a model of adiposity that displays increased levels of fat, glucose, and liver lipids. Our hypothesis is that HO-1 overexpression ameliorates fatty liver development. Methods Obese mice were administered cobalt protoporphyrin (CoPP) and stannic mesoporphyrin (SnMP) for 6 weeks. Heme, HO-1, HO activity, PGC1α, FGF21, glycogen content, and lipogenesis were assessed. Results CoPP administration increased hepatic HO-1 protein levels and HO activity, decreased hepatic heme, body weight gain, glucose levels, and resulted in decreased steatosis. Increased levels of HO-1 produced a decrease in lipid droplet size, Fatty acid synthase (FAS) levels involving recruitment …

Increased Ho-1 Levels Ameliorate Fatty Liver Development Through A Reduction Of Heme And Recruitment Of Fgf21, Terry Hinds, Komal Sodhi, Charles Meadows, Nader Abraham, Larisa Fedorova, Nitin Puri, Dong Kim, Stephen Peterson, Joseph Shapiro, Attallah Kappas

Nader G. Abraham

Objective Obese leptin deficient (ob/ob) mice are a model of adiposity that displays increased levels of fat, glucose, and liver lipids. Our hypothesis is that HO-1 overexpression ameliorates fatty liver development. Methods Obese mice were administered cobalt protoporphyrin (CoPP) and stannic mesoporphyrin (SnMP) for 6 weeks. Heme, HO-1, HO activity, PGC1α, FGF21, glycogen content, and lipogenesis were assessed. Results CoPP administration increased hepatic HO-1 protein levels and HO activity, decreased hepatic heme, body weight gain, glucose levels, and resulted in decreased steatosis. Increased levels of HO-1 produced a decrease in lipid droplet size, Fatty acid synthase (FAS) levels involving recruitment …

Involvement Of Reactive Oxygen Species In A Feed-Forward Mechanism Of Na/K-Atpase Mediated Signaling, Yanling Yan, Anna P. Shapiro, Steven Haller, Vinal Katragadda, Lijun Liu, Jiang Tian, Venkatesha Basrur, Deepak Malhotra, Zi-Jian Xie, Nader G. Abraham, Joseph I. Shapiro Md, Jiang Liu

Nader G. Abraham

Cardiotonic steroids (such as ouabain) signaling through Na/K-ATPase regulate sodium reabsorption in the renal proximal tubule. We report here that reactive oxygen species are required to initiate ouabain-stimulated Na/K-ATPase·c-Src signaling. Pretreatment with the antioxidant N-acetyl-L-cysteine prevented ouabain-stimulated Na/K-ATPase·c-Src signaling, protein carbonylation, redistribution of Na/K-ATPase and sodium/proton exchanger isoform 3, and inhibition of active transepithelial 22Na+ transport. Disruption of the Na/K-ATPase·c-Src signaling complex attenuated ouabain-stimulated protein carbonylation. Ouabain-stimulated protein carbonylation is reversed after removal of ouabain, and this reversibility is largely independent of de novo protein synthesis and degradation by either the lysosome or the proteasome pathways. Furthermore, ouabain stimulated direct …

Cyclooxygenase-2 Dependent Metabolism Of 20-Hete Increases Adiposity And Adipocyte Enlargement In Mesenchymal Stem Cell-Derived Adipocytes, Dong Kim, Nitin Puri, Komal Sodhi, John Falck, Nader Abraham, Joseph Shapiro, Michal Schwartzman

Nader G. Abraham

Abstract 20-Hydroxy-5,8,11,14-eicosatetraenoic acid (20-HETE), a product of the cytochrome P450 (CYP)-catalyzed [1] -hydroxylation of arachidonic acid, induces oxidative stress and, in clinical studies, is associated with increased body mass index (BMI) and the metabolic syndrome. This study was designed to examine the effects of exogenous 20- HETE on mesenchymal stem cell (MSC)-derived adipocytes. The expression levels of CYP4A11 and CYP4F2 (major 20-HETE synthases in humans) in MSCs decreased during adipocyte differentiation; however, exogenous administration of 20-HETE (0.1–1 M) increased adipogenesis in a dose dependent manner in these cells ( P < 0.05). The inability of a 20-HETE analog to reproduce these …

Cyclooxygenase-2 Dependent Metabolism Of 20-Hete Increases Adiposity And Adipocyte Enlargement In Mesenchymal Stem Cell-Derived Adipocytes, Dong Hyun Kim, Nitin Puri, Komal Sodhi, John R. Falck, Nader G. Abraham, Joseph I. Shapiro M.D., Michal L. Schwartzman

Komal Sodhi

Abstract 20-Hydroxy-5,8,11,14-eicosatetraenoic acid (20-HETE), a product of the cytochrome P450 (CYP)-catalyzed [1] -hydroxylation of arachidonic acid, induces oxidative stress and, in clinical studies, is associated with increased body mass index (BMI) and the metabolic syndrome. This study was designed to examine the effects of exogenous 20- HETE on mesenchymal stem cell (MSC)-derived adipocytes. The expression levels of CYP4A11 and CYP4F2 (major 20-HETE synthases in humans) in MSCs decreased during adipocyte differentiation; however, exogenous administration of 20-HETE (0.1–1 M) increased adipogenesis in a dose dependent manner in these cells ( P < 0.05). The inability of a 20-HETE analog to reproduce these …

Gender Differences In The Development Of Uremic Cardiomyopathy Following Partial Nephrectomy: Role Of Progesterone, Christopher Drummond, George Buddny, Steven Haller, Jiang Liu, Yanling Yan, Zijian Xie, Deepak Malhotra, Joseph Shapiro, Jiang Tian

Zijian Xie

Gender difference has been suggested as a risk factor for developing cardiovascular and renal diseases in humans and experimental animals. As a major sex hormone, progesterone was reported to compete with cardiotonic steroid binding to Na/K-ATPase. Our previous publication demonstrated that cardiotonic steroids (e.g., marinobufagenin) play an important role in the development of experimental uremic cardiomyopathy. We also observed that the putative mineralocorticoid antagonists, spironolactone and its major metabolite canrenone, antagonize binding of cardiotonic steroids to Na/K-ATPase in a competitive manner and also ameliorate experimental uremic cardiomyopathy induced by partial nephrectomy. In the following studies, we noted that progesterone displayed …

Cyclooxygenase-2 Dependent Metabolism Of 20-Hete Increases Adiposity And Adipocyte Enlargement In Mesenchymal Stem Cell-Derived Adipocytes, Dong Hyun Kim, Nitin Puri, Komal Sodhi, John R. Falck, Nader G. Abraham, Joseph I. Shapiro M.D., Michal L. Schwartzman

Joseph I Shapiro MD

Abstract 20-Hydroxy-5,8,11,14-eicosatetraenoic acid (20-HETE), a product of the cytochrome P450 (CYP)-catalyzed [1] -hydroxylation of arachidonic acid, induces oxidative stress and, in clinical studies, is associated with increased body mass index (BMI) and the metabolic syndrome. This study was designed to examine the effects of exogenous 20- HETE on mesenchymal stem cell (MSC)-derived adipocytes. The expression levels of CYP4A11 and CYP4F2 (major 20-HETE synthases in humans) in MSCs decreased during adipocyte differentiation; however, exogenous administration of 20-HETE (0.1–1 M) increased adipogenesis in a dose dependent manner in these cells ( P < 0.05). The inability of a 20-HETE analog to reproduce these …

Gender Differences In The Development Of Uremic Cardiomyopathy Following Partial Nephrectomy: Role Of Progesterone, Christopher A. Drummond, George Buddny, Steven T. Haller, Jiang Liu, Yanling Yan, Zijian Xie, Deepak Malhotra, Joseph I. Shapiro Md, Jiang Tian

Joseph I Shapiro MD

Gender difference has been suggested as a risk factor for developing cardiovascular and renal diseases in humans and experimental animals. As a major sex hormone, progesterone was reported to compete with cardiotonic steroid binding to Na/K-ATPase. Our previous publication demonstrated that cardiotonic steroids (e.g., marinobufagenin) play an important role in the development of experimental uremic cardiomyopathy. We also observed that the putative mineralocorticoid antagonists, spironolactone and its major metabolite canrenone, antagonize binding of cardiotonic steroids to Na/K-ATPase in a competitive manner and also ameliorate experimental uremic cardiomyopathy induced by partial nephrectomy. In the following studies, we noted that progesterone displayed …

Involvement Of Reactive Oxygen Species In A Feed-Forward Mechanism Of Na/K-Atpase Mediated Signaling, Yanling Yan, Anna P. Shapiro, Steven Haller, Vinal Katragadda, Lijun Liu, Jiang Tian, Venkatesha Basrur, Deepak Malhotra, Zi-Jian Xie, Nader G. Abraham, Joseph I. Shapiro Md, Jiang Liu

Joseph I Shapiro MD

Cardiotonic steroids (such as ouabain) signaling through Na/K-ATPase regulate sodium reabsorption in the renal proximal tubule. We report here that reactive oxygen species are required to initiate ouabain-stimulated Na/K-ATPase·c-Src signaling. Pretreatment with the antioxidant N-acetyl-L-cysteine prevented ouabain-stimulated Na/K-ATPase·c-Src signaling, protein carbonylation, redistribution of Na/K-ATPase and sodium/proton exchanger isoform 3, and inhibition of active transepithelial 22Na+ transport. Disruption of the Na/K-ATPase·c-Src signaling complex attenuated ouabain-stimulated protein carbonylation. Ouabain-stimulated protein carbonylation is reversed after removal of ouabain, and this reversibility is largely independent of de novo protein synthesis and degradation by either the lysosome or the proteasome pathways. Furthermore, ouabain stimulated direct …

Gender Differences In The Development Of Uremic Cardiomyopathy Following Partial Nephrectomy: Role Of Progesterone, Christopher A. Drummond, George Buddny, Steven T. Haller, Jiang Liu, Yanling Yan, Zijian Xie, Deepak Malhotra, Joseph I. Shapiro Md, Jiang Tian

Jiang Liu

Gender difference has been suggested as a risk factor for developing cardiovascular and renal diseases in humans and experimental animals. As a major sex hormone, progesterone was reported to compete with cardiotonic steroid binding to Na/K-ATPase. Our previous publication demonstrated that cardiotonic steroids (e.g., marinobufagenin) play an important role in the development of experimental uremic cardiomyopathy. We also observed that the putative mineralocorticoid antagonists, spironolactone and its major metabolite canrenone, antagonize binding of cardiotonic steroids to Na/K-ATPase in a competitive manner and also ameliorate experimental uremic cardiomyopathy induced by partial nephrectomy. In the following studies, we noted that progesterone displayed …

Involvement Of Reactive Oxygen Species In A Feed-Forward Mechanism Of Na/K-Atpase Mediated Signaling, Yanling Yan, Anna P. Shapiro, Steven Haller, Vinal Katragadda, Lijun Liu, Jiang Tian, Venkatesha Basrur, Deepak Malhotra, Zi-Jian Xie, Nader G. Abraham, Joseph I. Shapiro Md, Jiang Liu

Jiang Liu

Cardiotonic steroids (such as ouabain) signaling through Na/K-ATPase regulate sodium reabsorption in the renal proximal tubule. We report here that reactive oxygen species are required to initiate ouabain-stimulated Na/K-ATPase·c-Src signaling. Pretreatment with the antioxidant N-acetyl-L-cysteine prevented ouabain-stimulated Na/K-ATPase·c-Src signaling, protein carbonylation, redistribution of Na/K-ATPase and sodium/proton exchanger isoform 3, and inhibition of active transepithelial 22Na+ transport. Disruption of the Na/K-ATPase·c-Src signaling complex attenuated ouabain-stimulated protein carbonylation. Ouabain-stimulated protein carbonylation is reversed after removal of ouabain, and this reversibility is largely independent of de novo protein synthesis and degradation by either the lysosome or the proteasome pathways. Furthermore, ouabain stimulated direct …

Positive Selection Drives Preferred Segment Combinations During Influenza Virus Reassortment, Konstantin Zeldovich, Ping Liu, Nicholas Renzette, Matthieu Foll, Serena Pham, Sergey Venev, Glen Gallagher, Daniel Bolon, Evelyn Kurt-Jones, Jeffrey Jensen, Daniel Caffrey, Celia Schiffer, Timothy Kowalik, Jennifer Wang, Robert Finberg

Celia A. Schiffer

Influenza A virus (IAV) has a segmented genome that allows for the exchange of genome segments between different strains. This reassortment accelerates evolution by breaking linkage, helping IAV cross species barriers to potentially create highly virulent strains. Challenges associated with monitoring the process of reassortment in molecular detail have limited our understanding of its evolutionary implications. We applied a novel deep sequencing approach with quantitative analysis to assess the in vitro temporal evolution of genomic reassortment in IAV. The combination of H1N1 and H3N2 strains reproducibly generated a new H1N2 strain with the hemagglutinin and nucleoprotein segments originating from H1N1 …

A Laminin 511 Matrix Is Regulated By Taz And Functions As The Ligand For The Alpha6bbeta1 Integrin To Sustain Breast Cancer Stem Cells, Cheng Chang, Hira Lal Goel, Huijie Gao, Bryan M. Pursell, Leonard D. Shultz, Dale L. Greiner, Sulev Ingerpuu, Manuel Patarroyo, Shiliang Cao, Elgene Lim, Junhao Mao, Karen Kulju. Mckee, Peter D. Yurchenco, Arthur M. Mercurio

Arthur M. Mercurio

Understanding how the extracellular matrix impacts the function of cancer stem cells (CSCs) is a significant but poorly understood problem. We report that breast CSCs produce a laminin (LM) 511 matrix that promotes self-renewal and tumor initiation by engaging the alpha6Bbeta1 integrin and activating the Hippo transducer TAZ. Although TAZ is important for the function of breast CSCs, the mechanism is unknown. We observed that TAZ regulates the transcription of the alpha5 subunit of LM511 and the formation of a LM511 matrix. These data establish a positive feedback loop involving TAZ and LM511 that contributes to stemness in breast cancer.

Hnrnp A1 And Secondary Structure Coordinate Alternative Splicing Of Mag, Nancy Zearfoss, Emily Johnson, Sean Ryder

Sean P. Ryder

Myelin-associated glycoprotein (MAG) is a major component of myelin in the vertebrate central nervous system. MAG is present in the periaxonal region of the myelin structure, where it interacts with neuronal proteins to inhibit axon outgrowth and protect neurons from degeneration. Two alternatively spliced isoforms of Mag mRNA have been identified. The mRNA encoding the shorter isoform, known as S-MAG, contains a termination codon in exon 12, while the mRNA encoding the longer isoform, known as L-MAG, skips exon 12 and produces a protein with a longer C-terminal region. L-MAG is required in the central nervous system. How inclusion of …

Argonaute Protein Identity And Pairing Geometry Determine Cooperativity In Mammalian Rna Silencing, Jennifer Broderick, William Salomon, Sean Ryder, Neil Aronin, Phillip Zamore

Sean P. Ryder

Small RNAs loaded into Argonaute proteins direct silencing of complementary target mRNAs. It has been proposed that multiple, imperfectly complementary small interfering RNAs or microRNAs, when bound to the 3' untranslated region of a target mRNA, function cooperatively to silence target expression. We report that, in cultured human HeLa cells and mouse embryonic fibroblasts, Argonaute1 (Ago1), Ago3, and Ago4 act cooperatively to silence both perfectly and partially complementary target RNAs bearing multiple small RNA-binding sites. Our data suggest that for Ago1, Ago3, and Ago4, multiple, adjacent small RNA-binding sites facilitate cooperative interactions that stabilize Argonaute binding. In contrast, small RNAs …

The Effects Of Acute And Chronic Hypoxia On Cortisol, Glucose And Lactate Concentrations In Different Populations Of Three-Spined Stickleback, E. A. O'Connor, T. G. Pottinger, L. U. Sneddon

Lynne Sneddon, PhD

The response of individuals from three different populations of three-spined sticklebacks to acute and chronic periods of hypoxia (4.4 kPa DO, 2.2 mg l-1) were tested using measures of whole-body (WB) cortisol, glucose and lactate. Although there was no evidence of a neuroendocrine stress response to acute hypoxia, fish from the population least likely to experience hypoxia in their native habitat had the largest response to low oxygen, with significant evidence of anaerobic glycolysis after two hours of hypoxia. However, there was no measurable effect of a more prolonged period (seven days) of hypoxia on any of the fish in …

Nonenzymatic Glycosylation Of Erythrocyte Membrane Proteins. Relevance To Diabetes, J A. Miller, Ellen M. Gravallese, H F. Bunn

Ellen M. Gravallese

Nonenzymatic glycosylation of proteins of the erythrocyte membrane was determined by incubating erythrocyte ghosts with [3H]borohydride. The incorporation of tritium into protein provides a reliable assay of ketoamine linkages. The membrane proteins from 18 patients with diabetes incorporated twice as much radioactivity as membrane proteins from normal erythrocytes. After acid hydrolysis, amino acid analysis showed that the majority of radioactivity was localized to glucosyllysine. Autoradiograms showed that all of the major proteins of the erythrocyte membrane, separated by electrophoresis on sodium dodecyl sulfate gels, contained ketoamine linkages. No protein bands in either normal or diabetic erythrocytes showed significant preferential labeling. …

Development Of A Novel Screening Strategy Designed To Discover A New Class Of Hiv Drugs, Nancy Cheng, Sook-Kyung Lee, P. Donover, Mel Reichman, Celia Schiffer, Emily Hull-Ryde, Ronald Swanstrom, William Janzen

Celia A. Schiffer

Current antiretroviral treatments target multiple pathways important for human immunodeficiency virus (HIV) multiplication, including viral entry, synthesis and integration of the DNA provirus, and the processing of viral polyprotein precursors. However, HIV is becoming increasingly resistant to these "combination therapies." Recent findings show that inhibition of HIV Gag protein cleavage into its two structural proteins, matrix (MA) and capsid (CA), has a devastating effect on viral production, revealing a potential new target class for HIV treatment. Unlike the widely used HIV protease inhibitors, this new class of inhibitor would target the substrate, not the protease enzyme itself. This approach offers …

Interview With Celia Schiffer, Celia Schiffer

Celia A. Schiffer

Celia Schiffer, a Professor in Biochemistry and Molecular Pharmacology; a former Director of UMass Center for AIDS Research; and a Founder and Co-Director for the Institute for Drug Resistance (University of Massachusetts Medical School, MA, USA). Schiffer has an undergraduate degree in physics from the University of Chicago, with a PhD in biophysics from University of California, San Francisco (CA, USA). She was a postdoctoral associate first at the ETH in Zurich and then at Genentech in San Francisco. Schiffer has published more than 100 peer reviewed journal articles. Her laboratory primarily uses structural biology, biophysical and chemistry techniques to …

Prototypical Recombinant Multi-Protease Inhibitor Resistant Infectious Molecular Clones Of Human Immunodeficiency Virus Type-1, Vici Varghese, Yumi Mitsuya, W. Jeffrey Fessel, Tommy F. Liu, George Melikian, David Katzenstein, Celia Schiffer, Susan Holmes, Robert Shafer

Celia A. Schiffer

The many genetic manifestations of HIV-1 protease inhibitor (PI) resistance present challenges to research into the mechanisms of PI-resistance and the assessment of new PIs. To address these challenges, we created a panel of recombinant multi-PI resistant infectious molecular clones designed to represent the spectrum of clinically relevant multi-PI resistant viruses. To assess the representativeness of this panel, we examined the sequences of the panel's viruses in the context of a correlation network of PI-resistance amino acid substitutions in sequences from more than 10,000 patients. The panel of recombinant infectious molecular clones comprised 29 of 41 study-defined PI-resistance amino acid …

Dysfunctional Conformational Dynamics Of Protein Kinase A Induced By A Lethal Mutant Of Phospholamban Hinder Phosphorylation, Jonggul Kim, Larry R. Masterson, Alessandro Cembran, Raffaello Verardi, Lei Shi, Jiali Gao, Susan S. Taylor, Gianluigi Veglia

Larry Masterson