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Sample records for cells restore cardiac

  1. Optogenetics-enabled assessment of viral gene and cell therapy for restoration of cardiac excitability

    PubMed Central

    Ambrosi, Christina M.; Boyle, Patrick M.; Chen, Kay; Trayanova, Natalia A.; Entcheva, Emilia

    2015-01-01

    Multiple cardiac pathologies are accompanied by loss of tissue excitability, which leads to a range of heart rhythm disorders (arrhythmias). In addition to electronic device therapy (i.e. implantable pacemakers and cardioverter/defibrillators), biological approaches have recently been explored to restore pacemaking ability and to correct conduction slowing in the heart by delivering excitatory ion channels or ion channel agonists. Using optogenetics as a tool to selectively interrogate only cells transduced to produce an exogenous excitatory ion current, we experimentally and computationally quantify the efficiency of such biological approaches in rescuing cardiac excitability as a function of the mode of application (viral gene delivery or cell delivery) and the geometry of the transduced region (focal or spatially-distributed). We demonstrate that for each configuration (delivery mode and spatial pattern), the optical energy needed to excite can be used to predict therapeutic efficiency of excitability restoration. Taken directly, these results can help guide optogenetic interventions for light-based control of cardiac excitation. More generally, our findings can help optimize gene therapy for restoration of cardiac excitability. PMID:26621212

  2. Stem cell sources for cardiac regeneration.

    PubMed

    Roccio, M; Goumans, M J; Sluijter, J P G; Doevendans, P A

    2008-03-01

    Cell-based cardiac repair has the ambitious aim to replace the malfunctioning cardiac muscle developed after myocardial infarction, with new contractile cardiomyocytes and vessels. Different stem cell populations have been intensively studied in the last decade as a potential source of new cardiomyocytes to ameliorate the injured myocardium, compensate for the loss of ventricular mass and contractility and eventually restore cardiac function. An array of cell types has been explored in this respect, including skeletal muscle, bone marrow derived stem cells, embryonic stem cells (ESC) and more recently cardiac progenitor cells. The best-studied cell types are mouse and human ESC cells, which have undisputedly been demonstrated to differentiate into cardiomyocyte and vascular lineages and have been of great help to understand the differentiation process of pluripotent cells. However, due to their immunogenicity, risk of tumor development and the ethical challenge arising from their embryonic origin, they do not provide a suitable cell source for a regenerative therapy approach. A better option, overcoming ethical and allogenicity problems, seems to be provided by bone marrow derived cells and by the recently identified cardiac precursors. This report will overview current knowledge on these different cell types and their application in cardiac regeneration and address issues like implementation of delivery methods, including tissue engineering approaches that need to be developed alongside.

  3. Heart Regeneration with Embryonic Cardiac Progenitor Cells and Cardiac Tissue Engineering.

    PubMed

    Tian, Shuo; Liu, Qihai; Gnatovskiy, Leonid; Ma, Peter X; Wang, Zhong

    Myocardial infarction (MI) is the leading cause of death worldwide. Recent advances in stem cell research hold great potential for heart tissue regeneration through stem cell-based therapy. While multiple cell types have been transplanted into MI heart in preclinical studies or clinical trials, reduction of scar tissue and restoration of cardiac function have been modest. Several challenges hamper the development and application of stem cell-based therapy for heart regeneration. Application of cardiac progenitor cells (CPCs) and cardiac tissue engineering for cell therapy has shown great promise to repair damaged heart tissue. This review presents an overview of the current applications of embryonic CPCs and the development of cardiac tissue engineering in regeneration of functional cardiac tissue and reduction of side effects for heart regeneration. We aim to highlight the benefits of the cell therapy by application of CPCs and cardiac tissue engineering during heart regeneration.

  4. Cardiac regeneration: stem cells and beyond.

    PubMed

    Moerkamp, A T; Goumans, Marie-Jose

    2012-01-01

    After myocardial infarction, the lost healthy myocardium is replaced by non-contractile scar tissue which may lead to the development of heart failure and death. There is no curative therapy for the irreversible myocardial cell loss. This review will give an overview of the current options to restore the contractile force of the heart: the different stem cell sources as therapeutic agents in cardiac repair as well as more novel approaches like the activation of endogenous cell populations, the use of paracrine factors and engineered heart tissue.

  5. Pre-transplantation specification of stem cells to cardiac lineage for regeneration of cardiac tissue.

    PubMed

    Mayorga, Maritza; Finan, Amanda; Penn, Marc

    2009-03-01

    Myocardial infarction (MI) is a lead cause of mortality in the Western world. Treatment of acute MI is focused on restoration of antegrade flow which inhibits further tissue loss, but does not restore function to damaged tissue. Chronic therapy for injured myocardial tissue involves medical therapy that attempts to minimize pathologic remodeling of the heart. End stage therapy for chronic heart failure (CHF) involves inotropic therapy to increase surviving cardiac myocyte function or mechanical augmentation of cardiac performance. Not until the point of heart transplantation, a limited resource at best, does therapy focus on the fundamental problem of needing to replace injured tissue with new contractile tissue. In this setting, the potential for stem cell therapy has garnered significant interest for its potential to regenerate or create new contractile cardiac tissue. While to date adult stem cell therapy in clinical trials has suggested potential benefit, there is waning belief that the approaches used to date lead to regeneration of cardiac tissue. As the literature has better defined the pathways involved in cardiac differentiation, preclinical studies have suggested that stem cell pretreatment to direct stem cell differentiation prior to stem cell transplantation may be a more efficacious strategy for inducing cardiac regeneration. Here we review the available literature on pre-transplantation conditioning of stem cells in an attempt to better understand stem cell behavior and their readiness in cell-based therapy for myocardial regeneration.

  6. The Role of Cardiac Side Population Cells in Cardiac Regeneration

    PubMed Central

    Yellamilli, Amritha; van Berlo, Jop H.

    2016-01-01

    The heart has a limited ability to regenerate. It is important to identify therapeutic strategies that enhance cardiac regeneration in order to replace cardiomyocytes lost during the progression of heart failure. Cardiac progenitor cells are interesting targets for new regenerative therapies because they are self-renewing, multipotent cells located in the heart. Cardiac side population cells (cSPCs), the first cardiac progenitor cells identified in the adult heart, have the ability to differentiate into cardiomyocytes, endothelial cells, smooth muscle cells, and fibroblasts. They become activated in response to cardiac injury and transplantation of cSPCs into the injured heart improves cardiac function. In this review, we will discuss the current literature on the progenitor cell properties and therapeutic potential of cSPCs. This body of work demonstrates the great promise cSPCs hold as targets for new regenerative strategies. PMID:27679798

  7. No evidence of myocardial restoration following transplantation of mononuclear bone marrow cells in coronary bypass grafting surgery patients based upon cardiac SPECT and 18F-PET

    PubMed Central

    Tossios, Paschalis; Müller-Ehmsen, Jochen; Schmidt, Matthias; Scheid, Christof; Ünal, Nermin; Moka, Detlef; Schwinger, Robert HG; Mehlhorn, Uwe

    2006-01-01

    Background We tested the hypothesis, that intramyocardial injection of mononuclear bone marrow cells combined with coronary artery bypass grafting (CABG) surgery improves tissue viability or function in infarct regions with non-viable myocardium as assessed by nuclear imaging techniques. Methods Thus far, 7 patients (60 ± 10 [SD] years) undergoing elective CABG surgery after a myocardial infarction were included in this study. Prior to sternotomy, bone marrow was harvested by sternal puncture. Mononuclear bone marrow cells were isolated by gradient centrifugation and resuspended in 2 ml volume of Hank's buffered salt solution. At the end of CABG surgery 10 injections of 0.2 ml each were applied to the core area and borderzones of the infarct. Global and regional perfusion and viability were evaluated by ECG-gated 99mTc-tetrofosmin myocardial single-photon emission computed tomograph (SPECT) imaging and 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) in all study patients < 6 days before and 3 months after the intervention. Results Non-viable segments indicating transmural defects were identified in 5 patients. Two patients were found to have non-transmural defects before surgery. Concomitant surgical revascularisation and bone marrow cell injection was performed in all patients without major complications. The median total injected mononuclear cell number was 7.0 × 107 (range: 0.8–20.4). At 3 months 99mTc-tetrofosmin SPECT and 18F-FDG-PET scanning showed in 5 patients (transmural defect n = 4; non-transmural defect n = 1) no change in myocardial viability and in two patients (transmural defect n = 1, non-transmural defect n = 1) enhanced myocardial viability by 75%. Overall, global and regional LV ejection fraction was not significantly increased after surgery compared with the preoperative value. Conclusion In CABG surgery patients with non-viable segments the concurrent use of intramyocardial cell transfer did not show any clear improvement in

  8. Cardiac regeneration: still a 21st century challenge in search for cardiac progenitors from stem cells and embryos.

    PubMed

    Neri, Tui; Stefanovic, Sonia; Pucéat, Michel

    2010-07-01

    Regeneration of the heart after a stroke would be the best biologic response to restore its function. However, although this phenomenon occurs in primitive organisms, the regenerative potential is lost in mammals. Thus, the search for an appropriate cardiac progenitor with the potential to differentiate into a functional cardiomyocyte in vitro and in vivo has been the subject of intensive investigation. We summarize the cardiogenic transcriptional pathway that constitutes the molecular scaffold to drive pluripotent stem cells toward a cardiac progenitor fate. Then we overview the literature on derivation of cardiac progenitors from both embryos and stem cells.

  9. Pluripotent Stem Cell Derived Cardiomyocytes for Cardiac Repair

    PubMed Central

    Lundy, Scott D.; Gantz, Jay A.; Pagan, Chelsea M.; Filice, Dominic; Laflamme, Michael A.

    2014-01-01

    Opinion Statement The adult mammalian heart has limited capacity for generation, so a major injury such as a myocardial infarction results in the permanent loss of up to one billion cardiomyocytes. The field of cardiac cell therapy aims to replace these lost contractile units with de novo cardiomyocytes to restore lost systolic function and prevent progression to heart failure. Arguably the ideal cell for this application is the human cardiomyocyte itself, which can electromechanically couple with host myocardium and contribute active systolic force. Pluripotent stem cells from both human embryonic or induced pluripotent lineages are attractive sources for cardiomyocytes, and preclinical investigation of these cells is in progress. Recent work has focused on efficient generation and purification of cardiomyocytes, tissue engineering efforts, and examining the consequences of cell transplantation from mechanical, vascular, and electrical standpoints. Here we discuss historical and contemporary aspects of pluripotent stem cell-based cardiac cell therapy, with an emphasis on recent preclinical studies with translational goals. PMID:24838687

  10. Role of Cardiac Stem Cells in Cardiac Pathophysiology: A Paradigm Shift in Human Myocardial Biology

    PubMed Central

    Leri, Annarosa; Kajstura, Jan; Anversa, Piero

    2012-01-01

    For nearly a century, the human heart has been viewed as a terminally differentiated post-mitotic organ in which the number of cardiomyocytes is established at birth and these cells persist throughout the lifespan of the organ and organism. However, the discovery that cardiac stem cells (CSCs) live in the heart and differentiate into the various cardiac cell lineages has changed profoundly our understanding of myocardial biology. CSCs regulate myocyte turnover and condition myocardial recovery following injury. This novel information imposes a reconsideration of the mechanisms involved in myocardial aging and the progression of cardiac hypertrophy to heart failure. Similarly, the processes implicated in the adaptation of the infarcted heart have to be dissected in terms of the critical role that CSCs and myocyte regeneration play in the restoration of myocardial mass and ventricular function. Several categories of cardiac progenitors have been described but, thus far, the c-kit-positive cell is the only class of resident cells with the biological and functional properties of tissue specific adult stem cells. PMID:21960726

  11. Resident cardiac progenitor cells: at the heart of regeneration.

    PubMed

    Bollini, Sveva; Smart, Nicola; Riley, Paul R

    2011-02-01

    Stem cell therapy has recently emerged as an innovative strategy over conventional cardiovascular treatments to restore cardiac function in patients affected by ischemic heart disease. Various stem cell populations have been tested and their potential for cardiac repair has been analyzed. Embryonic stem cells retain the greatest differentiation potential, but concerns persist with regard to their immunogenic and teratogenic effects. Although adult somatic stem cells are not tumourigenic and easier to use in an autologous setting, they exist in small numbers and possess reduced differentiation potential. Traditionally the heart was considered to be a post-mitotic organ; however, this dogma has recently been challenged with the identification of a reservoir of resident stem cells, defined as cardiac progenitor cells (CPCs). These endogenous progenitors may represent the best candidates for cardiovascular cell therapy, as they are tissue-specific, often pre-committed to a cardiac fate, and display a greater propensity to differentiate towards cardiovascular lineages. This review will focus on current research into the biology of CPCs and their regenerative potential. This article is part of a special issue entitled, "Cardiovascular Stem Cells Revisited".

  12. Cell-cell connection to cardiac disease.

    PubMed

    Sheikh, Farah; Ross, Robert S; Chen, Ju

    2009-08-01

    Intercalated disks (ICDs) are highly organized cell-cell adhesion structures, which connect cardiomyocytes to one another. They are composed of three major complexes: desmosomes, fascia adherens, and gap junctions. Desmosomes and fascia adherens junction are necessary for mechanically coupling and reinforcing cardiomyocytes, whereas gap junctions are essential for rapid electrical transmission between cells. Because human genetics and mouse models have revealed that mutations and/or deficiencies in various ICD components can lead to cardiomyopathies and arrhythmias, considerable attention has focused on the biologic function of the ICD. This review will discuss recent scientific developments related to the ICD and focus on its role in regulating cardiac muscle structure, signaling, and disease.

  13. Restoring the impaired cardiac calcium homeostasis and cardiac function in iron overload rats by the combined deferiprone and N-acetyl cysteine

    PubMed Central

    Wongjaikam, Suwakon; Kumfu, Sirinart; Khamseekaew, Juthamas; Chattipakorn, Siriporn C.; Chattipakorn, Nipon

    2017-01-01

    Intracellular calcium [Ca2+]i dysregulation plays an important role in the pathophysiology of iron overload cardiomyopathy. Although either iron chelators or antioxidants provide cardioprotection, a comparison of the efficacy of deferoxamine (DFO), deferiprone (DFP), deferasirox (DFX), N-acetyl cysteine (NAC) or a combination of DFP plus NAC on cardiac [Ca2+]i homeostasis in chronic iron overload has never been investigated. Male Wistar rats were fed with either a normal diet or a high iron (HFe) diet for 4 months. At 2 months, HFe rats were divided into 6 groups and treated with either a vehicle, DFO (25 mg/kg/day), DFP (75 mg/kg/day), DFX (20 mg/kg/day), NAC (100 mg/kg/day), or combined DFP plus NAC. At 4 months, the number of cardiac T-type calcium channels was increased, whereas cardiac sarcoplasmic-endoplasmic reticulum Ca2+ ATPase (SERCA) was decreased, leading to cardiac iron overload and impaired cardiac [Ca2+]i homeostasis. All pharmacological interventions restored SERCA levels. Although DFO, DFP, DFX or NAC alone shared similar efficacy in improving cardiac [Ca2+]i homeostasis, only DFP + NAC restored cardiac [Ca2+]i homeostasis, leading to restoring left ventricular function in the HFe-fed rats. Thus, the combined DFP + NAC was more effective than any monotherapy in restoring cardiac [Ca2+]i homeostasis, leading to restored myocardial contractility in iron-overloaded rats. PMID:28287621

  14. Human embryonic stem cells and cardiac repair.

    PubMed

    Zhu, Wei-Zhong; Hauch, Kip D; Xu, Chunhui; Laflamme, Michael A

    2009-01-01

    The muscle lost after a myocardial infarction is replaced with noncontractile scar tissue, often initiating heart failure. Whole-organ cardiac transplantation is the only currently available clinical means of replacing the lost muscle, but this option is limited by the inadequate supply of donor hearts. Thus, cell-based cardiac repair has attracted considerable interest as an alternative means of ameliorating cardiac injury. Because of their tremendous capacity for expansion and unquestioned cardiac potential, pluripotent human embryonic stem cells (hESCs) represent an attractive candidate cell source for obtaining cardiomyocytes and other useful mesenchymal cell types for such therapies. Human embryonic stem cell-derived cardiomyocytes exhibit a committed cardiac phenotype and robust proliferative capacity, and recent testing in rodent infarct models indicates that they can partially remuscularize injured hearts and improve contractile function. Although the latter successes give good reason for optimism, considerable challenges remain in the successful application of hESCs to cardiac repair, including the need for preparations of high cardiac purity, improved methods of delivery, and approaches to overcome immune rejection and other causes of graft cell death. This review will describe the phenotype of hESC-derived cardiomyocytes and preclinical experience with these cells and will consider strategies to overcoming the aforementioned challenges.

  15. Cardiac Regeneration and Stem Cells

    PubMed Central

    Zhang, Yiqiang; Mignone, John; MacLellan, W. Robb

    2015-01-01

    After decades of believing the heart loses the ability to regenerate soon after birth, numerous studies are now reporting that the adult heart may indeed be capable of regeneration, although the magnitude of new cardiac myocyte formation varies greatly. While this debate has energized the field of cardiac regeneration and led to a dramatic increase in our understanding of cardiac growth and repair, it has left much confusion in the field as to the prospects of regenerating the heart. Studies applying modern techniques of genetic lineage tracing and carbon-14 dating have begun to establish limits on the amount of endogenous regeneration after cardiac injury, but the underlying cellular mechanisms of this regeneration remained unclear. These same studies have also revealed an astonishing capacity for cardiac repair early in life that is largely lost with adult differentiation and maturation. Regardless, this renewed focus on cardiac regeneration as a therapeutic goal holds great promise as a novel strategy to address the leading cause of death in the developed world. PMID:26269526

  16. Translational aspects of cardiac cell therapy

    PubMed Central

    Chen, Cheng-Han; Sereti, Konstantina-Ioanna; Wu, Benjamin M; Ardehali, Reza

    2015-01-01

    Cell therapy has been intensely studied for over a decade as a potential treatment for ischaemic heart disease. While initial trials using skeletal myoblasts, bone marrow cells and peripheral blood stem cells showed promise in improving cardiac function, benefits were found to be short-lived likely related to limited survival and engraftment of the delivered cells. The discovery of putative cardiac ‘progenitor’ cells as well as the creation of induced pluripotent stem cells has led to the delivery of cells potentially capable of electromechanical integration into existing tissue. An alternative strategy involving either direct reprogramming of endogenous cardiac fibroblasts or stimulation of resident cardiomyocytes to regenerate new myocytes can potentially overcome the limitations of exogenous cell delivery. Complimentary approaches utilizing combination cell therapy and bioengineering techniques may be necessary to provide the proper milieu for clinically significant regeneration. Clinical trials employing bone marrow cells, mesenchymal stem cells and cardiac progenitor cells have demonstrated safety of catheter based cell delivery, with suggestion of limited improvement in ventricular function and reduction in infarct size. Ongoing trials are investigating potential benefits to outcome such as morbidity and mortality. These and future trials will clarify the optimal cell types and delivery conditions for therapeutic effect. PMID:26119413

  17. Method of restoring degraded solar cells

    DOEpatents

    Staebler, David L.

    1983-01-01

    Amorphous silicon solar cells have been shown to have efficiencies which degrade as a result of long exposure to light. Annealing such cells in air at a temperature of about 200.degree. C. for at least 30 minutes restores their efficiency.

  18. Method of restoring degraded solar cells

    DOEpatents

    Staebler, D.L.

    1983-02-01

    Amorphous silicon solar cells have been shown to have efficiencies which degrade as a result of long exposure to light. Annealing such cells in air at a temperature of about 200 C for at least 30 minutes restores their efficiency. 2 figs.

  19. Methylene blue counteracts H2S toxicity-induced cardiac depression by restoring L-type Ca channel activity.

    PubMed

    Judenherc-Haouzi, Annick; Zhang, Xue-Qian; Sonobe, Takashi; Song, Jianliang; Rannals, Matthew D; Wang, JuFang; Tubbs, Nicole; Cheung, Joseph Y; Haouzi, Philippe

    2016-06-01

    We have previously reported that methylene blue (MB) can counteract hydrogen sulfide (H2S) intoxication-induced circulatory failure. Because of the multifarious effects of high concentrations of H2S on cardiac function, as well as the numerous properties of MB, the nature of this interaction, if any, remains uncertain. The aim of this study was to clarify 1) the effects of MB on H2S-induced cardiac toxicity and 2) whether L-type Ca(2+) channels, one of the targets of H2S, could transduce some of the counteracting effects of MB. In sedated rats, H2S infused at a rate that would be lethal within 5 min (24 μM·kg(-1)·min(-1)), produced a rapid fall in left ventricle ejection fraction, determined by echocardiography, leading to a pulseless electrical activity. Blood concentrations of gaseous H2S reached 7.09 ± 3.53 μM when cardiac contractility started to decrease. Two to three injections of MB (4 mg/kg) transiently restored cardiac contractility, blood pressure, and V̇o2, allowing the animals to stay alive until the end of H2S infusion. MB also delayed PEA by several minutes following H2S-induced coma and shock in unsedated rats. Applying a solution containing lethal levels of H2S (100 μM) on isolated mouse cardiomyocytes significantly reduced cell contractility, intracellular calcium concentration ([Ca(2+)]i) transient amplitudes, and L-type Ca(2+) currents (ICa) within 3 min of exposure. MB (20 mg/l) restored the cardiomyocyte function, ([Ca(2+)]i) transient, and ICa The present results offer a new approach for counteracting H2S toxicity and potentially other conditions associated with acute inhibition of L-type Ca(2+) channels.

  20. Removal of Abnormal Myofilament O-GlcNAcylation Restores Ca2+ Sensitivity in Diabetic Cardiac Muscle

    PubMed Central

    Ma, Junfeng; Slawson, Chad; Zeidan, Quira; Lugo-Fagundo, Nahyr S.; Xu, Mingguo; Shen, Xiaoxu; Gao, Wei Dong; Caceres, Viviane; Chakir, Khalid; DeVine, Lauren; Cole, Robert N.; Marchionni, Luigi; Paolocci, Nazareno; Hart, Gerald W.; Murphy, Anne M.

    2015-01-01

    Contractile dysfunction and increased deposition of O-linked β-N-acetyl-d-glucosamine (O-GlcNAc) in cardiac proteins are a hallmark of the diabetic heart. However, whether and how this posttranslational alteration contributes to lower cardiac function remains unclear. Using a refined β-elimination/Michael addition with tandem mass tags (TMT)–labeling proteomic technique, we show that CpOGA, a bacterial analog of O-GlcNAcase (OGA) that cleaves O-GlcNAc in vivo, removes site-specific O-GlcNAcylation from myofilaments, restoring Ca2+ sensitivity in streptozotocin (STZ) diabetic cardiac muscles. We report that in control rat hearts, O-GlcNAc and O-GlcNAc transferase (OGT) are mainly localized at the Z-line, whereas OGA is at the A-band. Conversely, in diabetic hearts O-GlcNAc levels are increased and OGT and OGA delocalized. Consistent changes were found in human diabetic hearts. STZ diabetic hearts display increased physical interactions of OGA with α-actin, tropomyosin, and myosin light chain 1, along with reduced OGT and increased OGA activities. Our study is the first to reveal that specific removal of O-GlcNAcylation restores myofilament response to Ca2+ in diabetic hearts and that altered O-GlcNAcylation is due to the subcellular redistribution of OGT and OGA rather than to changes in their overall activities. Thus, preventing sarcomeric OGT and OGA displacement represents a new possible strategy for treating diabetic cardiomyopathy. PMID:26109417

  1. Multipotent Stem Cells in Cardiac Regeneration

    PubMed Central

    Karra, Ravi; Wu, Sean M.

    2008-01-01

    Summary The potential for stem cells to ameliorate or cure heart diseases has galvanized a cadre of cardiovascular translational and clinical scientists to take a “first-in-man” approach using autologous stem cells from a variety of tissues. However, recent clinical trial data show that when these cells are given by intracoronary infusion or direct myocardial injection, limited improvement in heart function occurs with no evidence of cardiomyogenesis. These studies illustrate the great need to understand the logic of cell-lineage commitment and the principles of cardiac differentiation. Recent identification of stem/progenitor cells of embryological origin with intrinsic competence to differentiate into multiple lineages within the heart offers new possibilities for cardiac regeneration. When combined with developments in nuclear reprogramming and provided that tumor risks and other challenges of embryonic cell transplantation can be overcome, the prospect of achieving autologous, cardiomyogenic, stem cell-based therapy may be within reach. PMID:18307403

  2. Cardiac stem cell aging and heart failure.

    PubMed

    Cesselli, Daniela; Aleksova, Aneta; Mazzega, Elisa; Caragnano, Angela; Beltrami, Antonio Paolo

    2017-01-19

    A side effect of the medical improvements of the last centuries is the progressive aging of the world population, which is estimated to reach the impressive number of 2 billion people with more than 65 years by 2050. As a consequence, age-related diseases, such as heart failure, will affect more and more patients in the next years. To understand the biological bases of these diseases will be a crucial task in order to find better treatments, and possibly slow age-related morbidity and mortality. Cardiac stem cells have been at the center of a heated debate and their potential involvement in cardiac homeostasis has been questioned. In this review, we summarize evidence obtained by independent groups, on different animal models and humans, that strongly support the important role played by immature, cardiac resident cells in the cardioprotection against heart failure.

  3. Stem cells and exosomes in cardiac repair.

    PubMed

    Singla, Dinender K

    2016-04-01

    Cardiac diseases currently lead in the number of deaths per year, giving rise an interest in transplanting embryonic and adult stem cells as a means to improve damaged tissue from conditions such as myocardial infarction and coronary artery disease. After testing these cells as a treatment option in both animal and human models, it is believed that these cells improve the damaged tissue primarily through the release of autocrine and paracrine factors. Major concerns such as teratoma formation, immune response, difficulty harvesting cells, and limited cell proliferation and differentiation, hinder the routine use of these cells as a treatment option in the clinic. The advent of stem cell-derived exosomes circumvent those concerns, while still providing the growth factors, miRNA, and additional cell protective factors that aid in repairing and regenerating the damaged tissue. These exosomes have been found to be anti-apoptotic, anti-fibrotic, pro-angiogenic, as well as enhance cardiac differentiation, all of which are key to repairing damaged tissue. As such, stem cell derived exosomes are considered to be a potential new and novel approach in the treatment of various cardiac diseases.

  4. Cardiac cell proliferation assessed by EdU, a novel analysis of cardiac regeneration.

    PubMed

    Zeng, Bin; Tong, Suiyang; Ren, Xiaofeng; Xia, Hao

    2016-08-01

    Emerging evidence suggests that mammalian hearts maintain the capacity for cardiac regeneration. Rapid and sensitive identification of cardiac cellular proliferation is prerequisite for understanding the underlying mechanisms and strategies of cardiac regeneration. The following immunologically related markers of cardiac cells were analyzed: cardiac transcription factors Nkx2.5 and Gata 4; specific marker of cardiomyocytes TnT; endothelial cell marker CD31; vascular smooth muscle marker smooth muscle myosin IgG; cardiac resident stem cells markers IsL1, Tbx18, and Wt1. Markers were co-localized in cardiac tissues of embryonic, neonatal, adult, and pathological samples by 5-ethynyl-2'-deoxyuridine (EdU) staining. EdU was also used to label isolated neonatal cardiomyocytes in vitro. EdU robustly labeled proliferating cells in vitro and in vivo, co-immunostaining with different cardiac cells markers. EdU can rapidly and sensitively label proliferating cardiac cells in developmental and pathological states. Cardiac cell proliferation assessed by EdU is a novel analytical tool for investigating the mechanism and strategies of cardiac regeneration in response to injury.

  5. Mechanical communication in cardiac cell synchronized beating

    NASA Astrophysics Data System (ADS)

    Nitsan, Ido; Drori, Stavit; Lewis, Yair E.; Cohen, Shlomi; Tzlil, Shelly

    2016-05-01

    Cell-cell communication, which enables cells to coordinate their activity and is essential for growth, development and function, is usually ascribed a chemical or electrical origin. However, cells can exert forces and respond to environment elasticity and to mechanical deformations created by their neighbours. The extent to which this mechanosensing ability facilitates intercellular communication remains unclear. Here we demonstrate mechanical communication between cells directly for the first time, providing evidence for a long-range interaction that induces long-lasting alterations in interacting cells. We show that an isolated cardiac cell can be trained to beat at a given frequency by mechanically stimulating the underlying substrate. Deformations are induced using an oscillatory mechanical probe that mimics the deformations generated by a beating neighbouring cardiac cell. Unlike electrical field stimulation, the probe-induced beating rate is maintained by the cell for an hour after the stimulation stops, implying that long-term modifications occur within the cell. These long-term alterations provide a mechanism for cells that communicate mechanically to be less variable in their electromechanical delay. Mechanical coupling between cells therefore ensures that the final outcome of action potential pacing is synchronized beating. We further show that the contractile machinery is essential for mechanical communication.

  6. Therapeutic application of cardiac stem cells and other cell types.

    PubMed

    Hayashi, Emiko; Hosoda, Toru

    2013-01-01

    Various researches on regenerative medicine were carried out experimentally, and selected modalities have been introduced to the clinical arena. Meanwhile, the presence of resident stem cells in the heart and their role in physiological cell turnover were demonstrated. So far skeletal myoblasts, bone marrow-derived cells, mesenchymal stromal cells, and resident cardiac cells have been applied for therapeutic myocardial regeneration. Among them, autologous transplantation of c-kit-positive cardiac stem cells in congestive heart failure patients resulted in an outstanding outcome, with long-lasting beneficial effects without major adverse events. By reviewing these clinical trials, an endeavor was made to seek for an ideal cellular therapy for cardiovascular diseases.

  7. Transplantation of multipotent Isl1+ cardiac progenitor cells preserves infarcted heart function in mice

    PubMed Central

    Li, Yunpeng; Tian, Shuo; Lei, Ienglam; Liu, Liu; Ma, Peter; Wang, Zhong

    2017-01-01

    Cell-based cardiac therapy is a promising therapeutic strategy to restore heart function after myocardial infarction (MI). However, the cell type selection and ensuing effects remain controversial. Here, we intramyocardially injected Isl1+ cardiac progenitor cells (CPCs) derived from EGFP/luciferase double-tagged mouse embryonic stem (dt-mES) cells with vehicle (fibrin gel) or phosphate-buffered saline (PBS) into the infarcted area in nude mice to assess the contribution of CPCs to the recovery of cardiac function post-MI. Our results showed that Isl1+ CPCs differentiated normally into three cardiac lineages (cardiomyocytes (CMs), endothelial cells and smooth muscle cells) both on cell culture plates and in fibrin gel. Cell retention was significantly increased when the transplanted cells were injected with vehicle. Importantly, 28 days after injection, CPCs were observed to differentiate into CMs within the infarcted area. Moreover, numerous CD31+ endothelial cells derived from endogenous revascularization and differentiation of the injected CPCs were detected. SMMHC-, Ki67- and CX-43-positive cells were identified in the injected CPC population, further demonstrating the proliferation, differentiation and integration of the transplanted CPCs in host cells. Furthermore, animal hearts injected with CPCs showed increased angiogenesis, decreased infarct size, and improved heart function. In conclusion, our studies showed that Isl1+ CPCs, when combined with a suitable vehicle, can produce notable therapeutic effects in the infarcted heart, suggesting that CPCs might be an ideal cell source for cardiac therapy. PMID:28386378

  8. Transplantation of multipotent Isl1+ cardiac progenitor cells preserves infarcted heart function in mice.

    PubMed

    Li, Yunpeng; Tian, Shuo; Lei, Ienglam; Liu, Liu; Ma, Peter; Wang, Zhong

    2017-01-01

    Cell-based cardiac therapy is a promising therapeutic strategy to restore heart function after myocardial infarction (MI). However, the cell type selection and ensuing effects remain controversial. Here, we intramyocardially injected Isl1+ cardiac progenitor cells (CPCs) derived from EGFP/luciferase double-tagged mouse embryonic stem (dt-mES) cells with vehicle (fibrin gel) or phosphate-buffered saline (PBS) into the infarcted area in nude mice to assess the contribution of CPCs to the recovery of cardiac function post-MI. Our results showed that Isl1+ CPCs differentiated normally into three cardiac lineages (cardiomyocytes (CMs), endothelial cells and smooth muscle cells) both on cell culture plates and in fibrin gel. Cell retention was significantly increased when the transplanted cells were injected with vehicle. Importantly, 28 days after injection, CPCs were observed to differentiate into CMs within the infarcted area. Moreover, numerous CD31+ endothelial cells derived from endogenous revascularization and differentiation of the injected CPCs were detected. SMMHC-, Ki67- and CX-43-positive cells were identified in the injected CPC population, further demonstrating the proliferation, differentiation and integration of the transplanted CPCs in host cells. Furthermore, animal hearts injected with CPCs showed increased angiogenesis, decreased infarct size, and improved heart function. In conclusion, our studies showed that Isl1+ CPCs, when combined with a suitable vehicle, can produce notable therapeutic effects in the infarcted heart, suggesting that CPCs might be an ideal cell source for cardiac therapy.

  9. Improving Cell Engraftment in Cardiac Stem Cell Therapy

    PubMed Central

    Xie, Xiaoyun

    2016-01-01

    Myocardial infarction (MI) affects millions of people worldwide. MI causes massive cardiac cell death and heart function decrease. However, heart tissue cannot effectively regenerate by itself. While stem cell therapy has been considered an effective approach for regeneration, the efficacy of cardiac stem cell therapy remains low due to inferior cell engraftment in the infarcted region. This is mainly a result of low cell retention in the tissue and poor cell survival under ischemic, immune rejection and inflammatory conditions. Various approaches have been explored to improve cell engraftment: increase of cell retention using biomaterials as cell carriers; augmentation of cell survival under ischemic conditions by preconditioning cells, genetic modification of cells, and controlled release of growth factors and oxygen; and enhancement of cell survival by protecting cells from excessive inflammation and immune surveillance. In this paper, we review current progress, advantages, disadvantages, and potential solutions of these approaches. PMID:26783405

  10. Cardiac regeneration using human embryonic stem cells: producing cells for future therapy.

    PubMed

    Wong, Sharon S Y; Bernstein, Harold S

    2010-09-01

    Directed differentiation of human embryonic stem cells (hESCs) has generated much interest in the field of regenerative medicine. Because of their ability to differentiate into any cell type in the body, hESCs offer a novel therapeutic paradigm for myocardial repair by furnishing a supply of cardiomyocytes (CMs) that would ultimately restore normal myocardial function when delivered to the damaged heart. Spontaneous CM differentiation of hESCs is an inefficient process that yields very low numbers of CMs. In addition, it is not clear that fully differentiated CMs provide the benefits sought from cell transplantation. The need for new methods of directed differentiation of hESCs into functional CMs and cardiac progenitors has led to an explosion of research utilizing chemical, genetic, epigenetic and lineage selection strategies to direct cardiac differentiation and enrich populations of cardiac cells for therapeutic use. Here, we review these approaches and highlight their increasingly important roles in stem cell biology and cardiac regenerative medicine.

  11. CARDIAC-LIKE OSCILLATION IN LIVER STEM CELLS INDUCE THEIR ACQUISITION OF CARDIAC PHENOTYPE

    EPA Science Inventory

    We examined in a cardiac microenvironment the plasticity of a liver stem cell line (WB F344) generated from a cloned, single, non-parenchymal epithelial cell from a normal adult male rat. Our previous studies suggested that WB F344 cells acquire a cardiac phenotype in the absenc...

  12. In Vivo Tracking of Cell Therapies for Cardiac Diseases with Nuclear Medicine

    PubMed Central

    Moreira, Mayra Lorena; da Costa Medeiros, Priscylla; de Souza, Sergio Augusto Lopes; Rosado-de-Castro, Paulo Henrique

    2016-01-01

    Even though heart diseases are amongst the main causes of mortality and morbidity in the world, existing treatments are limited in restoring cardiac lesions. Cell transplantations, originally developed for the treatment of hematologic ailments, are presently being explored in preclinical and clinical trials for cardiac diseases. Nonetheless, little is known about the possible efficacy and mechanisms for these therapies and they are the center of continuous investigation. In this scenario, noninvasive imaging techniques lead to greater comprehension of cell therapies. Radiopharmaceutical cell labeling, firstly developed to track leukocytes, has been used successfully to evaluate the migration of cell therapies for myocardial diseases. A substantial rise in the amount of reports employing this methodology has taken place in the previous years. We will review the diverse radiopharmaceuticals, imaging modalities, and results of experimental and clinical studies published until now. Also, we report on current limitations and potential advances of radiopharmaceutical labeling for cell therapies in cardiac diseases. PMID:26880951

  13. Developmental origin and lineage plasticity of endogenous cardiac stem cells.

    PubMed

    Santini, Maria Paola; Forte, Elvira; Harvey, Richard P; Kovacic, Jason C

    2016-04-15

    Over the past two decades, several populations of cardiac stem cells have been described in the adult mammalian heart. For the most part, however, their lineage origins and in vivo functions remain largely unexplored. This Review summarizes what is known about different populations of embryonic and adult cardiac stem cells, including KIT(+), PDGFRα(+), ISL1(+)and SCA1(+)cells, side population cells, cardiospheres and epicardial cells. We discuss their developmental origins and defining characteristics, and consider their possible contribution to heart organogenesis and regeneration. We also summarize the origin and plasticity of cardiac fibroblasts and circulating endothelial progenitor cells, and consider what role these cells have in contributing to cardiac repair.

  14. Cyclosporin in cell therapy for cardiac regeneration.

    PubMed

    Jansen Of Lorkeers, S J; Hart, E; Tang, X L; Chamuleau, M E D; Doevendans, P A; Bolli, R; Chamuleau, S A J

    2014-07-01

    Stem cell therapy is a promising strategy in promoting cardiac repair in the setting of ischemic heart disease. Clinical and preclinical studies have shown that cell therapy improves cardiac function. Whether autologous or allogeneic cells should be used, and the need for immunosuppression in non-autologous settings, is a matter of debate. Cyclosporin A (CsA) is frequently used in preclinical trials to reduce cell rejection after non-autologous cell therapy. The direct effect of CsA on the function and survival of stem cells is unclear. Furthermore, the appropriate daily dosage of CsA in animal models has not been established. In this review, we discuss the pros and cons of the use of CsA on an array of stem cells both in vitro and in vivo. Furthermore, we present a small collection of data put forth by our group supporting the efficacy and safety of a specific daily CsA dosage in a pig model.

  15. Cardiac myofibroblast engulfment of dead cells facilitates recovery after myocardial infarction

    PubMed Central

    Watari, Kenji; Tajima, Mitsuru; Nakaya, Takeo; Matsuda, Shoichi; Ohara, Hiroki; Nishihara, Hiroaki; Yamaguchi, Hiroshi; Hashimoto, Akiko; Nishida, Mitsuho; Nagasaka, Akiomi; Horii, Yuma; Ono, Hiroki; Iribe, Gentaro; Inoue, Kazuhide; Tanaka, Akira; Kuroda, Masahiko; Nagata, Shigekazu

    2016-01-01

    Myocardial infarction (MI) results in the generation of dead cells in the infarcted area. These cells are swiftly removed by phagocytes to minimize inflammation and limit expansion of the damaged area. However, the types of cells and molecules responsible for the engulfment of dead cells in the infarcted area remain largely unknown. In this study, we demonstrated that cardiac myofibroblasts, which execute tissue fibrosis by producing extracellular matrix proteins, efficiently engulf dead cells. Furthermore, we identified a population of cardiac myofibroblasts that appears in the heart after MI in humans and mice. We found that these cardiac myofibroblasts secrete milk fat globule-epidermal growth factor 8 (MFG-E8), which promotes apoptotic engulfment, and determined that serum response factor is important for MFG-E8 production in myofibroblasts. Following MFG-E8–mediated engulfment of apoptotic cells, myofibroblasts acquired antiinflammatory properties. MFG-E8 deficiency in mice led to the accumulation of unengulfed dead cells after MI, resulting in exacerbated inflammatory responses and a substantial decrease in survival. Moreover, MFG-E8 administration into infarcted hearts restored cardiac function and morphology. MFG-E8–producing myofibroblasts mainly originated from resident cardiac fibroblasts and cells that underwent endothelial-mesenchymal transition in the heart. Together, our results reveal previously unrecognized roles of myofibroblasts in regulating apoptotic engulfment and a fundamental importance of these cells in recovery from MI. PMID:27918308

  16. Cardiac Cells Beating in Culture: A Laboratory Exercise

    ERIC Educational Resources Information Center

    Weaver, Debora

    2007-01-01

    This article describes how to establish a primary tissue culture, where cells are taken directly from an organ of a living animal. Cardiac cells are taken from chick embryos and transferred to culture dishes. These cells are not transformed and therefore have a limited life span. However, the unique characteristics of cardiac cells are maintained…

  17. Restoration of β -Adrenergic Signaling in Failing Cardiac Ventricular Myocytes via Adenoviral-Mediated Gene Transfer

    NASA Astrophysics Data System (ADS)

    Akhter, Shahab A.; Skaer, Christine A.; Kypson, Alan P.; McDonald, Patricia H.; Peppel, Karsten C.; Glower, Donald D.; Lefkowitz, Robert J.; Koch, Walter J.

    1997-10-01

    Cardiovascular gene therapy is a novel approach to the treatment of diseases such as congestive heart failure (CHF). Gene transfer to the heart would allow for the replacement of defective or missing cellular proteins that may improve cardiac performance. Our laboratory has been focusing on the feasibility of restoring β -adrenergic signaling deficiencies that are a characteristic of chronic CHF. We have now studied isolated ventricular myocytes from rabbits that have been chronically paced to produce hemodynamic failure. We document molecular β -adrenergic signaling defects including down-regulation of myocardial β -adrenergic receptors (β -ARs), functional β -AR uncoupling, and an upregulation of the β -AR kinase (β ARK1). Adenoviral-mediated gene transfer of the human β 2-AR or an inhibitor of β ARK1 to these failing myocytes led to the restoration of β -AR signaling. These results demonstrate that defects present in this critical myocardial signaling pathway can be corrected in vitro using genetic modification and raise the possibility of novel inotropic therapies for CHF including the inhibition of β ARK1 activity in the heart.

  18. Cell-Specific Cardiac Electrophysiology Models

    PubMed Central

    Groenendaal, Willemijn; Ortega, Francis A.; Kherlopian, Armen R.; Zygmunt, Andrew C.; Krogh-Madsen, Trine; Christini, David J.

    2015-01-01

    The traditional cardiac model-building paradigm involves constructing a composite model using data collected from many cells. Equations are derived for each relevant cellular component (e.g., ion channel, exchanger) independently. After the equations for all components are combined to form the composite model, a subset of parameters is tuned, often arbitrarily and by hand, until the model output matches a target objective, such as an action potential. Unfortunately, such models often fail to accurately simulate behavior that is dynamically dissimilar (e.g., arrhythmia) to the simple target objective to which the model was fit. In this study, we develop a new approach in which data are collected via a series of complex electrophysiology protocols from single cardiac myocytes and then used to tune model parameters via a parallel fitting method known as a genetic algorithm (GA). The dynamical complexity of the electrophysiological data, which can only be fit by an automated method such as a GA, leads to more accurately parameterized models that can simulate rich cardiac dynamics. The feasibility of the method is first validated computationally, after which it is used to develop models of isolated guinea pig ventricular myocytes that simulate the electrophysiological dynamics significantly better than does a standard guinea pig model. In addition to improving model fidelity generally, this approach can be used to generate a cell-specific model. By so doing, the approach may be useful in applications ranging from studying the implications of cell-to-cell variability to the prediction of intersubject differences in response to pharmacological treatment. PMID:25928268

  19. Targeting chronic cardiac remodeling with cardiac progenitor cells in a murine model of ischemia/reperfusion injury

    PubMed Central

    Deddens, Janine C.; Feyen, Dries A.; Zwetsloot, Peter-Paul; Brans, Maike A.; Siddiqi, Sailay; van Laake, Linda W.; Doevendans, Pieter A.; Sluijter, Joost P.

    2017-01-01

    Background Translational failure for cardiovascular disease is a substantial problem involving both high research costs and an ongoing lack of novel treatment modalities. Despite the progress already made, cell therapy for chronic heart failure in the clinical setting is still hampered by poor translation. We used a murine model of chronic ischemia/reperfusion injury to examine the effect of minimally invasive application of cardiac progenitor cells (CPC) in cardiac remodeling and to improve clinical translation. Methods 28 days after the induction of I/R injury, mice were randomized to receive either CPC (0.5 million) or vehicle by echo-guided intra-myocardial injection. To determine retention, CPC were localized in vivo by bioluminescence imaging (BLI) two days after injection. Cardiac function was assessed by 3D echocardiography and speckle tracking analysis to quantify left ventricular geometry and regional myocardial deformation. Results BLI demonstrated successful injection of CPC (18/23), which were mainly located along the needle track in the anterior/septal wall. Although CPC treatment did not result in overall restoration of cardiac function, a relative preservation of the left ventricular end-diastolic volume was observed at 4 weeks follow-up compared to vehicle control (+5.3 ± 2.1 μl vs. +10.8 ± 1.5 μl). This difference was reflected in an increased strain rate (+16%) in CPC treated mice. Conclusions CPC transplantation can be adequately studied in chronic cardiac remodeling using this study set-up and by that provide a translatable murine model facilitating advances in research for new therapeutic approaches to ultimately improve therapy for chronic heart failure. PMID:28319168

  20. Generation of cardiac pacemaker cells by programming and differentiation.

    PubMed

    Husse, Britta; Franz, Wolfgang-Michael

    2016-07-01

    A number of diseases are caused by faulty function of the cardiac pacemaker and described as "sick sinus syndrome". The medical treatment of sick sinus syndrome with electrical pacemaker implants in the diseased heart includes risks. These problems may be overcome via "biological pacemaker" derived from different adult cardiac cells or pluripotent stem cells. The generation of cardiac pacemaker cells requires the understanding of the pacing automaticity. Two characteristic phenomena the "membrane-clock" and the "Ca(2+)-clock" are responsible for the modulation of the pacemaker activity. Processes in the "membrane-clock" generating the spontaneous pacemaker firing are based on the voltage-sensitive membrane ion channel activity starting with slow diastolic depolarization and discharging in the action potential. The influence of the intracellular Ca(2+) modulating the pacemaker activity is characterized by the "Ca(2+)-clock". The generation of pacemaker cells started with the reprogramming of adult cardiac cells by targeted induction of one pacemaker function like HCN1-4 overexpression and enclosed in an activation of single pacemaker specific transcription factors. Reprogramming of adult cardiac cells with the transcription factor Tbx18 created cardiac cells with characteristic features of cardiac pacemaker cells. Another key transcription factor is Tbx3 specifically expressed in the cardiac conduction system including the sinoatrial node and sufficient for the induction of the cardiac pacemaker gene program. For a successful cell therapeutic practice, the generated cells should have all regulating mechanisms of cardiac pacemaker cells. Otherwise, the generated pacemaker cells serve only as investigating model for the fundamental research or as drug testing model for new antiarrhythmics. This article is part of a Special Issue entitled: Cardiomyocyte Biology: Integration of Developmental and Environmental Cues in the Heart edited by Marcus Schaub and Hughes Abriel.

  1. ANGPTL8 reverses established adriamycin cardiomyopathy by stimulating adult cardiac progenitor cells

    PubMed Central

    Chen, Shuyuan; Chen, Jiaxi; Meng, Xing-Li; Shen, Jin-Song; Huang, Jing; Huang, Pintong; Pu, Zhaoxia; McNeill, Nathan H.; Grayburn, Paul A.

    2016-01-01

    Established adriamycin cardiomyopathy is a lethal disease. When congestive heart failure develops, mortality is approximately 50% in a year. It has been known that ANGPTLs has various functions in lipid metabolism, inflammation, cancer cell invasion, hematopoietic stem activity and diabetes. We hypothesized that ANGPTL8 is capable of maintaining heart function by stimulating adult cardiac progenitor cells to initiate myocardial regeneration. We employed UTMD to deliver piggybac transposon plasmids with the human ANGPTL8 gene to the liver of rats with adriamycin cardiomyopathy. After ANGPTL8 gene liver delivery, overexpression of transgenic human ANGPTL8 was found in rat liver cells and blood. UTMD- ANGPTL8 gene therapy restored LV mass, fractional shortening index, and LV posterior wall diameter to nearly normal. Our results also showed that ANGPTL8 reversed established ADM cardiomyopathy. This was associated with activation of ISL-1 positive cardiac progenitor cells in the epicardium. A time-course experiment shown that ISL-1 cardiac progenitor cells proliferated and formed a niche in the epicardial layer and then migrated into sub-epicardium. The observed myocardial regeneration accompanying reversal of adriamycin cardiomyopathy was associated with upregulation of PirB expression on the cell membrane of cardiac muscle cells or progenitor cells stimulated by ANGPTL8. PMID:27823982

  2. 3D culture for cardiac cells.

    PubMed

    Zuppinger, Christian

    2016-07-01

    This review discusses historical milestones, recent developments and challenges in the area of 3D culture models with cardiovascular cell types. Expectations in this area have been raised in recent years, but more relevant in vitro research, more accurate drug testing results, reliable disease models and insights leading to bioartificial organs are expected from the transition to 3D cell culture. However, the construction of organ-like cardiac 3D models currently remains a difficult challenge. The heart consists of highly differentiated cells in an intricate arrangement.Furthermore, electrical “wiring”, a vascular system and multiple cell types act in concert to respond to the rapidly changing demands of the body. Although cardiovascular 3D culture models have been predominantly developed for regenerative medicine in the past, their use in drug screening and for disease models has become more popular recently. Many sophisticated 3D culture models are currently being developed in this dynamic area of life science. This article is part of a Special Issue entitled: Cardiomyocyte Biology: Integration of Developmental and Environmental Cues in the Heart edited by Marcus Schaub and Hughes Abriel.

  3. Copper inhibition of hydrogen peroxide-induced hypertrophy in embryonic rat cardiac H9c2 cells.

    PubMed

    Zhou, Yang; Jiang, Youchun; Kang, Y James

    2007-03-01

    Previous studies have shown that dietary copper deficiency causes cardiac hypertrophy and depression of vascular epithelial growth factor (VEGF) expression in mouse model. Copper replenishment in the diet reverses cardiac hypertrophy and restores VEGF expression. The present study was undertaken to specifically determine the role of VEGF in copper effect on cell hypertrophy. Embryonic rat cardiac H9c2 cells were exposed to hydrogen peroxide to develop hypertrophy, determined by increases in cell size and total protein content. Copper addition at 5 microM in cultures suppressed cell hypertrophy. In the presence of anti-VEGF antibody, copper inhibitory effect on cell hypertrophy was blunted, and VEGF alone mimicked the inhibitory effect of copper. The results thus demonstrated that VEGF is critically involved in copper inhibition of cell hypertrophy induced by hydrogen peroxide in the H9c2 cells.

  4. Restoring forces in cardiac myocytes. Insight from relaxations induced by photolysis of caged ATP.

    PubMed Central

    Niggli, E; Lederer, W J

    1991-01-01

    Concentration jumps of intracellular ATP were produced by photolysis of P3-1-(2-nitrophenyl)ethyl (NPE)-caged ATP and were used to investigate the passive relengthening properties in unloaded cardiac myocytes. Patch-clamp pipettes in the whole-cell mode were used to voltage-clamp the myocytes and to load the cells with caged ATP while optical methods were applied to record sarcomere length or cell length simultaneously. Cell length was varied using energy deprivation contractures while intracellular Ca2+ was controlled with EGTA. At sarcomere lengths between 1.8 and 1.4 microns cellular relengthening after photolysis of caged ATP was rapid (t1/2 approximately 100 ms) and could be well described by a simple mechanical model. However, ATP jumps made at sarcomere lengths approximately 1.1 microns led to slow relengthening (t1/2 approximately seconds), comparable to the slow reextensions observed in skinned myocytes after bulk solution changes. We attribute the slow and incomplete relengthening of intact and skinned myocytes after severe rigor shortening to deformation and alteration of structural elements inside the cell. Relengthening from intermediate sarcomere lengths in intact cells is elastic and provides information about the underlying relengthening forces inside the cell. The data do not support the presence of a significant discontinuity in elastic modulus at a sarcomere length of approximately 1.6 microns expected from ultrastructural features of the sarcomeres and from observations in skinned myocytes. Our results suggest that the cell length measurements usually performed in this preparation provide an adequate description of the force produced by the unloaded cell in the steady state. The results also provide a way to estimate the error arising from viscous forces during rapid shortening. PMID:1868157

  5. Predictors for severe cardiac complications after hematopoietic stem cell transplantation.

    PubMed

    Sakata-Yanagimoto, M; Kanda, Y; Nakagawa, M; Asano-Mori, Y; Kandabashi, K; Izutsu, K; Imai, Y; Hangaishi, A; Kurokawa, M; Tsujino, S; Ogawa, S; Chiba, S; Motokura, T; Hirai, H

    2004-05-01

    The value of pre-transplant factors for predicting the development of cardiac complications after transplantation has been inconsistent among studies. We analyzed the impact of pre-transplant factors on the incidence of severe cardiac complications in 164 hematopoietic stem cell transplant recipients. We identified eight patients (4.8%) who experienced grade III or IV cardiac complications according to the Bearman criteria. Seven died of cardiac causes a median of 3 days after the onset of cardiac complications. On univariate analysis, both the cumulative dose of anthracyclines and the use of anthracyclines within 60 days before transplantation affected the incidence of severe cardiac complications (P=0.0091 and 0.011). The dissociation of heart rate and body temperature, which reflects "relative tachycardia", was also associated with a higher incidence of cardiac complications (P=0.024). None of the variables obtained by electrocardiography or echocardiography were useful for predicting cardiac complications after transplantation, although the statistical power might not be sufficient to detect the usefulness of ejection fraction. On a multivariate analysis, the cumulative dose of anthracyclines was the only independent significant risk factor for severe cardiac complications. We conclude that the cumulative dose of anthracyclines is the most potent predictor of cardiac complications and the administration of anthracyclines should be avoided within two months before transplantation.

  6. Cardiac Resynchronization Therapy Restores Sympathovagal Balance in the Failing Heart by Differential Remodeling of Cholinergic Signaling

    PubMed Central

    DeMazumder, Deeptankar; Kass, David A.; O’Rourke, Brian; Tomaselli, Gordon F.

    2015-01-01

    Rationale Cardiac resynchronization therapy (CRT) is the only heart failure (HF) therapy documented to improve left ventricular (LV) function and reduce mortality. The underlying mechanisms are incompletely understood. While β-adrenergic signaling has been studied extensively, the effect of CRT on cholinergic signaling is unexplored. Objective We hypothesized that remodeling of cholinergic signaling plays an important role in the aberrant calcium signaling and depressed contractile and β-adrenergic responsiveness in dyssynchronous HF (DHF) that are restored by CRT. Methods and Results Canine tachypaced DHF and CRT models were generated to interrogate responses specific to dyssynchronous vs. resynchronized ventricular contraction during hemodynamic decompensation. Echocardiographic, electrocardiographic and invasive hemodynamic data were collected from normal controls, DHF and CRT models. LV tissue was used for biochemical analyses and functional measurements (calcium transient, sarcomere shortening) from isolated myocytes (N=42–104 myocytes/model; 6–9 hearts/model). Human LV myocardium was obtained for biochemical analyses from explanted failing (N=18) and non-failing (N=7) hearts. The M2 subtype of muscarinic acetylcholine receptors (M2-mAChR) was upregulated in human and canine HF compared to non-failing controls. CRT attenuated the increased M2-mAChR expression and Gαi-coupling, and enhanced M3-mAChR expression in association with enhanced calcium cycling, sarcomere shortening and β-adrenergic responsiveness. Despite model-dependent remodeling, cholinergic stimulation completely abolished isoproterenol-induced triggered activity in both DHF and CRT myocytes. Conclusions Remodeling of cholinergic signaling is a critical pathological component of human and canine HF. Differential remodeling of cholinergic signaling represents a novel mechanism for enhancing sympathovagal balance with CRT and may identify new targets for treatment of systolic HF. PMID

  7. Cardiac tissue development for delivery of embryonic stem cell-derived endothelial and cardiac cells in natural matrices.

    PubMed

    Turner, William S; Wang, Xiaoling; Johnson, Scott; Medberry, Christopher; Mendez, Jose; Badylak, Stephen F; McCord, Marian G; McCloskey, Kara E

    2012-11-01

    The packaging and delivery of cells for cardiac regeneration has been explored using a variety biomaterials and delivery methods, but these studies often ignore one or more important design factors critical for rebuilding cardiac tissue. These include the biomaterial architecture, strength and stiffness, cell alignment, and/or incorporation of multiple cell types. In this article, we explore the combinatorial use of decellularized tissues, moldable hydrogels, patterned cell-seeding, and cell-sheet engineering and find that a combination of these methods is optimal in the recreation of transplantable cardiac-like tissue in vivo. We show that decellularized urinary bladder matrix (UBM), that is compliant and suturable, supports the survival of cell cultures but does not allow maintenance of cell-to-cell contacts of transferred cell-sheets (presumably, due to its rough surface). Moreover, the UBM material must be filled with hyaluronan (HA) hydrogels for smoothing rough surfaces and allowing the delivery of greater cell numbers. We additionally incorporated our previously developed "wrinkled" microchip for inducing alignment of cardiac cells with a laser-etched mask for co-seeding patterned "channels" of cells. This article also introduces a novel method of plasma coating for cell-sheet engineering that compares well with electron bean irradiation methods and may be combined with our "wrinkled" surfaces to facilitate the alignment of cardiac cells into sheets. Our data shows that an optimal design for generating cardiac tissue would include (1) decellularized matrix seeded with endothelial cells in a HA layered with (2) prealigned cardiac cell-sheets fabricated using our "wrinkled" microchips and thermo-responsive polymer [poly(N-isopropylacrylamide)] cell sheet transfer system.

  8. Embryonic stem cells in cardiac repair and regeneration.

    PubMed

    Singla, Dinender K

    2009-08-01

    Cell transplantation is a subject of fast-growing research with a potential of a therapeutic approach for the treatment of heart diseases. Clinical applications require preparation of large number of donor cells. Stem cell studies published to date demonstrate that scientists have not reached the general consensus to use an optimal cell type for better cardiac repair and regeneration. We used embryonic stem (ES) cells and their released factors for cardiac repair and regeneration. The major concern of cardiac regeneration with stem cells includes engraftment, differentiation, and teratoma formation after ES cell transplantation. Our current knowledge of ES cell transplantation in the heart is very limited. This review discusses the use of various growth factors to enhance ES cells engraftment and differentiation, as well as the issue of teratoma formation.

  9. Cardiac electromechanical models: from cell to organ.

    PubMed

    Trayanova, Natalia A; Rice, John Jeremy

    2011-01-01

    The heart is a multiphysics and multiscale system that has driven the development of the most sophisticated mathematical models at the frontiers of computational physiology and medicine. This review focuses on electromechanical (EM) models of the heart from the molecular level of myofilaments to anatomical models of the organ. Because of the coupling in terms of function and emergent behaviors at each level of biological hierarchy, separation of behaviors at a given scale is difficult. Here, a separation is drawn at the cell level so that the first half addresses subcellular/single-cell models and the second half addresses organ models. At the subcellular level, myofilament models represent actin-myosin interaction and Ca-based activation. The discussion of specific models emphasizes the roles of cooperative mechanisms and sarcomere length dependence of contraction force, considered to be the cellular basis of the Frank-Starling law. A model of electrophysiology and Ca handling can be coupled to a myofilament model to produce an EM cell model, and representative examples are summarized to provide an overview of the progression of the field. The second half of the review covers organ-level models that require solution of the electrical component as a reaction-diffusion system and the mechanical component, in which active tension generated by the myocytes produces deformation of the organ as described by the equations of continuum mechanics. As outlined in the review, different organ-level models have chosen to use different ionic and myofilament models depending on the specific application; this choice has been largely dictated by compromises between model complexity and computational tractability. The review also addresses application areas of EM models such as cardiac resynchronization therapy and the role of mechano-electric coupling in arrhythmias and defibrillation.

  10. Cardiac Electromechanical Models: From Cell to Organ

    PubMed Central

    Trayanova, Natalia A.; Rice, John Jeremy

    2011-01-01

    The heart is a multiphysics and multiscale system that has driven the development of the most sophisticated mathematical models at the frontiers of computational physiology and medicine. This review focuses on electromechanical (EM) models of the heart from the molecular level of myofilaments to anatomical models of the organ. Because of the coupling in terms of function and emergent behaviors at each level of biological hierarchy, separation of behaviors at a given scale is difficult. Here, a separation is drawn at the cell level so that the first half addresses subcellular/single-cell models and the second half addresses organ models. At the subcellular level, myofilament models represent actin–myosin interaction and Ca-based activation. The discussion of specific models emphasizes the roles of cooperative mechanisms and sarcomere length dependence of contraction force, considered to be the cellular basis of the Frank–Starling law. A model of electrophysiology and Ca handling can be coupled to a myofilament model to produce an EM cell model, and representative examples are summarized to provide an overview of the progression of the field. The second half of the review covers organ-level models that require solution of the electrical component as a reaction–diffusion system and the mechanical component, in which active tension generated by the myocytes produces deformation of the organ as described by the equations of continuum mechanics. As outlined in the review, different organ-level models have chosen to use different ionic and myofilament models depending on the specific application; this choice has been largely dictated by compromises between model complexity and computational tractability. The review also addresses application areas of EM models such as cardiac resynchronization therapy and the role of mechano-electric coupling in arrhythmias and defibrillation. PMID:21886622

  11. From ontogenesis to regeneration: learning how to instruct adult cardiac progenitor cells.

    PubMed

    Chimenti, Isotta; Forte, Elvira; Angelini, Francesco; Giacomello, Alessandro; Messina, Elisa

    2012-01-01

    Since the first observations over two centuries ago by Lazzaro Spallanzani on the extraordinary regenerative capacity of urodeles, many attempts have been made to understand the reasons why such ability has been largely lost in metazoa and whether or how it can be restored, even partially. In this context, important clues can be derived from the systematic analysis of the relevant distinctions among species and of the pathways involved in embryonic development, which might be induced and/or recapitulated in adult tissues. This chapter provides an overview on regeneration and its mechanisms, starting with the lesson learned from lower vertebrates, and will then focus on recent advancements and novel insights concerning regeneration in the adult mammalian heart, including the discovery of resident cardiac progenitor cells (CPCs). Subsequently, it explores all the important pathways involved in regulating differentiation during development and embryogenesis, and that might potentially provide important clues on how to activate and/or modulate regenerative processes in the adult myocardium, including the potential activation of endogenous CPCs. Furthermore the importance of the stem cell niche is discussed, and how it is possible to create in vitro a microenvironment and culture system to provide adult CPCs with the ideal conditions promoting their regenerative ability. Finally, the state of clinical translation of cardiac cell therapy is presented. Overall, this chapter provides a new perspective on how to approach cardiac regeneration, taking advantage of important lessons from development and optimizing biotechnological tools to obtain the ideal conditions for cell-based cardiac regenerative therapy.

  12. Dental stem cells as an alternative source for cardiac regeneration.

    PubMed

    Xin, Loo Zhang; Govindasamy, Vijayendran; Musa, Sabri; Abu Kasim, Noor Hayaty

    2013-10-01

    Dental tissues contains stem cells or progenitors that have high proliferative capacity, are clonogenic in vitro and demonstrate the ability to differentiate to multiple type cells involving neurons, bone, cartilage, fat and smooth muscle. Numerous experiments have demonstrated that the multipotent stem cells are not rejected by immune system and therefore it may be possible to use these cells in allogeneic settings. In addition, these remarkable cells are easily abundantly available couple with less invasive procedure in isolating comparing to bone marrow aspiration. Here we proposed dental stem cells as candidate for cardiac regeneration based on its immature characteristic and propensity towards cardiac lineage via PI3-Kinase/Aktsignalling pathway.

  13. Pluripotent Stem Cell Derived Cardiac Cells for Myocardial Repair.

    PubMed

    Zhu, Wuqiang; Gao, Ling; Zhang, Jianyi

    2017-02-03

    Human induced pluripotent stem cells (hiPSCs) must be fully differentiated into specific cell types before administration, but conventional protocols for differentiating hiPSCs into cardiomyocytes (hiPSC-CMs), endothelial cells (hiPSC-ECs), and smooth muscle cells (SMCs) are often limited by low yield, purity, and/or poor phenotypic stability. Here, we present novel protocols for generating hiPSC-CMs, -ECs, and -SMCs that are substantially more efficient than conventional methods, as well as a method for combining cell injection with a cytokine-containing patch created over the site of administration. The patch improves both the retention of the injected cells, by sealing the needle track to prevent the cells from being squeezed out of the myocardium, and cell survival, by releasing insulin-like growth factor (IGF) over an extended period. In a swine model of myocardial ischemia-reperfusion injury, the rate of engraftment was more than two-fold greater when the cells were administered with the cytokine-containing patch comparing to the cells without patch, and treatment with both the cells and the patch, but not with the cells alone, was associated with significant improvements in cardiac function and infarct size.

  14. Effects of carbon monoxide on cardiac muscle cells in culture

    SciTech Connect

    Nag, A.C.; Chen, K.C.; Cheng, Mei General Motors Research Laboratories, Warren, MI )

    1988-09-01

    Embryonic rat cardiac muscle cells grown in the presence of various tensions of CO (5-95%) without the presence of O{sub 2} survived and exhibited reduced cell growth, which was concentration dependent. When cardiac muscle cells were grown in the presence of a mixture of CO (10-20%) and O{sub 2} (10-20%), the growth rate of these cells was comparable to that of the control cells. Cardiac myocytes continued to beat when exposed to varying tensions of CO, except in the case of 95% CO. The cells exposed to different concentrations of CO contained fewer myofibrils of different stages of differentiation compared with the control and the culture exposed to a mixture of 20% O{sub 2} and 20% CO, with cells that contained abundant, highly differentiated myofibrils. There was no significant difference in the structural organization of mitochondria between the control and the surviving experimental cells. It is evident from the present studies that O{sub 2} is required for the optimum in vitro cellular growth of cardiac muscle. Furthermore, CO in combination with O{sub 2} at a concentration of 10 or 20% can produce optimal growth of cardiac muscle cells in culture. To determine maximum labeling index during the labeling period, cells were continuously labeled with ({sup 3}H)thymidine for 24 h before the termination of cultures.

  15. Microwave radiation effects on cardiac muscle cells in vitro

    SciTech Connect

    Galvin, M.J.; Hall, C.A.; McRee, D.I.

    1981-05-01

    Isolated cardiac muscle cells were exposed to microwave radiation in a temperature-controlled waveguide apparatus. Microwave radiation for 90 min at specific absorption rates (SAR) as low as 10 mW/g increases the permeability of cardiac cells to trypan blue. At 100 mW/g the inability of the cells to exclude trypan blue is concurrent with the release of lactic dehydrogenase into the suspending medium. However, when the SAR is decreased to 50 mW/g, trypan blue uptake is still elevated without the concomitant release of lactic dehydrogenase. Transmission electron micrographs of the exposed cells showed cellular damage only at the 100 mW/g exposure level. The microwave-reduced change in membrane permeability was unrelated to a macroscopic heating effect of microwave radiation on the cells, but appeared to be due to some other specific action of microwave radiation on isolated cardiac cells.

  16. Chemical genetics and its potential in cardiac stem cell therapy.

    PubMed

    Vieira, Joaquim M; Riley, Paul R

    2013-05-01

    Over the last decade or so, intensive research in cardiac stem cell biology has led to significant discoveries towards a potential therapy for cardiovascular disease; the main cause of morbidity and mortality in humans. The major goal within the field of cardiovascular regenerative medicine is to replace lost or damaged cardiac muscle and coronaries following ischaemic disease. At present, de novo cardiomyocytes can be generated either in vitro, for cell transplantation or disease modelling using directed differentiation of embryonic stem cells or induced pluripotent stem cells, or in vivo via direct reprogramming of resident adult cardiac fibroblast or ectopic stimulation of resident cardiac stem or progenitor cells. A major bottleneck with all of these approaches is the low efficiency of cardiomyocyte differentiation alongside their relative functional immaturity. Chemical genetics, and the application of phenotypic screening with small molecule libraries, represent a means to enhance understanding of the molecular pathways controlling cardiovascular cell differentiation and, moreover, offer the potential for discovery of new drugs to invoke heart repair and regeneration. Here, we review the potential of chemical genetics in cardiac stem cell therapy, highlighting not only the major contributions to the field so far, but also the future challenges.

  17. A multistaged automatic restoration of noisy microscopy cell images.

    PubMed

    Xu, Jinwei; Hu, Jiankun; Jia, Xiuping

    2015-01-01

    Automated cell segmentation for microscopy cell images has recently become an initial step for further image analysis in cell biology. However, microscopy cell images are easily degraded by noise during the readout procedure via optical-electronic imaging systems. Such noise degradations result in low signal-to-noise ratio (SNR) and poor image quality for cell identification. In order to improve SNR for subsequent segmentation and image-based quantitative analysis, the commonly used state-of-art restoration techniques are applied but few of them are suitable for corrupted microscopy cell images. In this paper, we propose a multistaged method based on a novel integration of trend surface analysis, quantile-quantile plot, bootstrapping, and the Gaussian spatial kernel for the restoration of noisy microscopy cell images. We show this multistaged approach achieves higher performance compared with other state-of-art restoration techniques in terms of peak signal-to-noise ratio and structure similarity in synthetic noise experiments. This paper also reports an experiment on real noisy microscopy data which demonstrated the advantages of the proposed restoration method for improving segmentation performance.

  18. Concise Review: Cardiac Disease Modeling Using Induced Pluripotent Stem Cells.

    PubMed

    Yang, Chunbo; Al-Aama, Jumana; Stojkovic, Miodrag; Keavney, Bernard; Trafford, Andrew; Lako, Majlinda; Armstrong, Lyle

    2015-09-01

    Genetic cardiac diseases are major causes of morbidity and mortality. Although animal models have been created to provide some useful insights into the pathogenesis of genetic cardiac diseases, the significant species differences and the lack of genetic information for complex genetic diseases markedly attenuate the application values of such data. Generation of induced pluripotent stem cells (iPSCs) from patient-specific specimens and subsequent derivation of cardiomyocytes offer novel avenues to study the mechanisms underlying cardiac diseases, to identify new causative genes, and to provide insights into the disease aetiology. In recent years, the list of human iPSC-based models for genetic cardiac diseases has been expanding rapidly, although there are still remaining concerns on the level of functionality of iPSC-derived cardiomyocytes and their ability to be used for modeling complex cardiac diseases in adults. This review focuses on the development of cardiomyocyte induction from pluripotent stem cells, the recent progress in heart disease modeling using iPSC-derived cardiomyocytes, and the challenges associated with understanding complex genetic diseases. To address these issues, we examine the similarity between iPSC-derived cardiomyocytes and their ex vivo counterparts and how this relates to the method used to differentiate the pluripotent stem cells into a cardiomyocyte phenotype. We progress to examine categories of congenital cardiac abnormalities that are suitable for iPSC-based disease modeling.

  19. Ultrastructural features of degenerated cardiac muscle cells in patients with cardiac hypertrophy.

    PubMed Central

    Maron, B. J.; Ferrans, V. J.; Roberts, W. C.

    1975-01-01

    Degenerated cardiac muscle cells were present in hypertrophied ventricular muscle obtained at operation from 12 (38%) of 32 patients with asymmetric septal hypertrophy (hypertrophic cardiomyopathy) or aortic valvular disease. Degenerated cells demonstrated a wide variety of ultrastructural alterations. Mildly altered cells were normal-sized or hypertrophied and showed focal changes, including preferential loss of thick (myosin) filaments, streaming and clumping of Z band material, and proliferation of the tubules of sarcoplasmic reticulum. Moderately and severely degenerated cells were normal-sized or atrophic and showed additional changes, including extensive myofibrillar lysis and loss of T tubules. The appearance of the most severely degenerated cells usually reflected the cytoplasmic organelle (sarcoplasmic reticulum, glycogen, or mitochondria) which underwent proliferation and filled the myofibril-free areas of these cells. Moderately and severely degenerated cells were present in areas of fibrosis, had thickened basement membranes, and had lost their intercellular connections. These observations suggest that degenerated cardiac muscle cells have poor contractile function and may be responsible for impaired cardiac performance in some patients with chronic ventricular hypertrophy. Images Fig 1 Fig 2 Fig 3 Figs 4-6 Figs 7-8 Fig 9 Fig 10 Fig 11 Figs 12-15 Fig 16 Fig 17 Figs 18-21 Figs 22-23 Fig 24 Fig 25 Fig 26 Fig 27 Figs 28-29 Fig 30 Figs 31-32 Fig 33 PMID:124533

  20. Restoration of normal phenotype in cancer cells

    DOEpatents

    Bissell, Mina J.; Weaver, Valerie M.

    1998-01-01

    A method for reversing expression of malignant phenotype in cancer cells is described. The method comprises applying .beta..sub.1 integrin function-blocking antibody to the cells. The method can be used to assess the progress of cancer therapy. Human breast epithelial cells were shown to be particularly responsive.

  1. Restoration of normal phenotype in cancer cells

    DOEpatents

    Bissell, M.J.; Weaver, V.M.

    1998-12-08

    A method for reversing expression of malignant phenotype in cancer cells is described. The method comprises applying {beta}{sub 1} integrin function-blocking antibody to the cells. The method can be used to assess the progress of cancer therapy. Human breast epithelial cells were shown to be particularly responsive. 14 figs.

  2. Spatiotemporal Tracking of Cells in Tissue Engineered Cardiac Organoids

    PubMed Central

    Iyer, Rohin K.; Chui, Jane; Radisic, Milica

    2009-01-01

    Cardiac tissue engineering aims to create myocardial patches for repair of defective or damaged native heart muscle. The inclusion of non-myocytes in engineered cardiac tissues has been shown to improve the properties of cardiac tissue compared to tissues engineered from enriched populations of myocytes alone. While attempts to mix non-myocytes (fibroblasts, endothelial cells) with cardiomyocytes have been made, very little is understood about how the tissue properties are affected by varying the respective ratios of the three cell types and how these cells assemble into functional tissues with time. The goal of this study was to investigate the effects of modulating the ratios of the three cell types as well as to spatially and temporally track cardiac tri-cultures of cells. Primary neonatal cardiac fibroblasts and D4T endothelial cells were incubated in 5µM of CellTracker™ Green dye and CellTracker™ Red dye respectively while neonatal cardiomyocytes were labeled with 20µg/mL of DAPI. The non-myocytes were seeded either sequentially (Pre-culture) or simultaneously (Tri-culture) in Matrigel-coated microchannels and allowed to form organoids, as in our previous studies. We also varied the seeding percentage of cardiomyocytes while keeping the total cell number constant in an attempt to improve the functional properties of the organoids. Organoids were imaged on days 1 and 4. Endothelial cells were seen to aggregate into clusters when Simultaneously Tri-cultured with myocytes and fibroblasts, while Pre-cultures contained elongated cells. Functional properties of organoids were improved by increasing the seeding percentage of enriched cardiomyocytes from 40% to 80%. PMID:19235264

  3. Restoration of angiogenic capacity of diabetes-insulted mesenchymal stem cells by oxytocin

    PubMed Central

    2013-01-01

    Background Angiogenesis is the main therapeutic mechanism of cell therapy for cardiovascular diseases, but diabetes is reported to reduce the function and number of progenitor cells. Therefore, we studied the effect of streptozotocin-induced diabetes on the bone marrow-mesenchymal stem cell (MSC) function, and examined whether diabetes-impaired MSC could be rescued by pretreatment with oxytocin. Results MSCs were isolated and cultured from diabetic (DM) or non-diabetic (non-DM) rat, and proliferation rate was compared. DM-MSC was pretreated with oxytocin and compared with non-DM-MSC. Angiogenic capacity was estimated by tube formation and Matrigel plug assay, and therapeutic efficacy was studied in rat myocardial infarction (MI) model. The proliferation and angiogenic activity of DM-MSC were severely impaired but significantly improved by pretreatment with oxytocin. Krüppel-like factor 2 (KLF2), a critical angiogenic factor, was dramatically reduced in DM-MSC and significantly restored by oxytocin. In the Matrigel plug assay, vessel formation of DM-BMSCs was attenuated but was recovered by oxytocin. In rat MI model, DM-MSC injection did not ameliorate cardiac injury, whereas oxytocin-pretreated DM-MSC improved cardiac function and reduced fibrosis. Conclusions Our results show that diabetes influenced MSC by reducing angiogenic capacity and therapeutic potential. We demonstrate the striking effect of oxytocin on stem cell dysfunction and suggest the use of oxytocin as a priming reagent in autologous stem cell therapy. PMID:24024790

  4. Optimizing stem cells for cardiac repair: Current status and new frontiers in regenerative cardiology

    PubMed Central

    Der Sarkissian, Shant; Lévesque, Thierry; Noiseux, Nicolas

    2017-01-01

    Cell therapy has the potential to improve healing of ischemic heart, repopulate injured myocardium and restore cardiac function. The tremendous hope and potential of stem cell therapy is well understood, yet recent trials involving cell therapy for cardiovascular diseases have yielded mixed results with inconsistent data thereby readdressing controversies and unresolved questions regarding stem cell efficacy for ischemic cardiac disease treatment. These controversies are believed to arise by the lack of uniformity of the clinical trial methodologies, uncertainty regarding the underlying reparative mechanisms of stem cells, questions concerning the most appropriate cell population to use, the proper delivery method and timing in relation to the moment of infarction, as well as the poor stem cell survival and engraftment especially in a diseased microenvironment which is collectively acknowledged as a major hindrance to any form of cell therapy. Indeed, the microenvironment of the failing heart exhibits pathological hypoxic, oxidative and inflammatory stressors impairing the survival of transplanted cells. Therefore, in order to observe any significant therapeutic benefit there is a need to increase resilience of stem cells to death in the transplant microenvironment while preserving or better yet improving their reparative functionality. Although stem cell differentiation into cardiomyocytes has been observed in some instance, the prevailing reparative benefits are afforded through paracrine mechanisms that promote angiogenesis, cell survival, transdifferentiate host cells and modulate immune responses. Therefore, to maximize their reparative functionality, ex vivo manipulation of stem cells through physical, genetic and pharmacological means have shown promise to enable cells to thrive in the post-ischemic transplant microenvironment. In the present work, we will overview the current status of stem cell therapy for ischemic heart disease, discuss the most recurring

  5. Optimizing stem cells for cardiac repair: Current status and new frontiers in regenerative cardiology.

    PubMed

    Der Sarkissian, Shant; Lévesque, Thierry; Noiseux, Nicolas

    2017-01-26

    Cell therapy has the potential to improve healing of ischemic heart, repopulate injured myocardium and restore cardiac function. The tremendous hope and potential of stem cell therapy is well understood, yet recent trials involving cell therapy for cardiovascular diseases have yielded mixed results with inconsistent data thereby readdressing controversies and unresolved questions regarding stem cell efficacy for ischemic cardiac disease treatment. These controversies are believed to arise by the lack of uniformity of the clinical trial methodologies, uncertainty regarding the underlying reparative mechanisms of stem cells, questions concerning the most appropriate cell population to use, the proper delivery method and timing in relation to the moment of infarction, as well as the poor stem cell survival and engraftment especially in a diseased microenvironment which is collectively acknowledged as a major hindrance to any form of cell therapy. Indeed, the microenvironment of the failing heart exhibits pathological hypoxic, oxidative and inflammatory stressors impairing the survival of transplanted cells. Therefore, in order to observe any significant therapeutic benefit there is a need to increase resilience of stem cells to death in the transplant microenvironment while preserving or better yet improving their reparative functionality. Although stem cell differentiation into cardiomyocytes has been observed in some instance, the prevailing reparative benefits are afforded through paracrine mechanisms that promote angiogenesis, cell survival, transdifferentiate host cells and modulate immune responses. Therefore, to maximize their reparative functionality, ex vivo manipulation of stem cells through physical, genetic and pharmacological means have shown promise to enable cells to thrive in the post-ischemic transplant microenvironment. In the present work, we will overview the current status of stem cell therapy for ischemic heart disease, discuss the most recurring

  6. Electrically Induced Calcium Handling in Cardiac Progenitor Cells

    PubMed Central

    Wagner, Mary B.

    2016-01-01

    For nearly a century, the heart was viewed as a terminally differentiated organ until the discovery of a resident population of cardiac stem cells known as cardiac progenitor cells (CPCs). It has been shown that the regenerative capacity of CPCs can be enhanced by ex vivo modification. Preconditioning CPCs could provide drastic improvements in cardiac structure and function; however, a systematic approach to determining a mechanistic basis for these modifications founded on the physiology of CPCs is lacking. We have identified a novel property of CPCs to respond to electrical stimulation by initiating intracellular Ca2+ oscillations. We used confocal microscopy and intracellular calcium imaging to determine the spatiotemporal properties of the Ca2+ signal and the key proteins involved in this process using pharmacological inhibition and confocal Ca2+ imaging. Our results provide valuable insights into mechanisms to enhance the therapeutic potential in stem cells and further our understanding of human CPC physiology. PMID:27818693

  7. Cardiac tissue engineering and regeneration using cell-based therapy

    PubMed Central

    Alrefai, Mohammad T; Murali, Divya; Paul, Arghya; Ridwan, Khalid M; Connell, John M; Shum-Tim, Dominique

    2015-01-01

    Stem cell therapy and tissue engineering represent a forefront of current research in the treatment of heart disease. With these technologies, advancements are being made into therapies for acute ischemic myocardial injury and chronic, otherwise nonreversible, myocardial failure. The current clinical management of cardiac ischemia deals with reestablishing perfusion to the heart but not dealing with the irreversible damage caused by the occlusion or stenosis of the supplying vessels. The applications of these new technologies are not yet fully established as part of the management of cardiac diseases but will become so in the near future. The discussion presented here reviews some of the pioneering works at this new frontier. Key results of allogeneic and autologous stem cell trials are presented, including the use of embryonic, bone marrow-derived, adipose-derived, and resident cardiac stem cells. PMID:25999743

  8. Electrical and mechanical stimulation of cardiac cells and tissue constructs.

    PubMed

    Stoppel, Whitney L; Kaplan, David L; Black, Lauren D

    2016-01-15

    The field of cardiac tissue engineering has made significant strides over the last few decades, highlighted by the development of human cell derived constructs that have shown increasing functional maturity over time, particularly using bioreactor systems to stimulate the constructs. However, the functionality of these tissues is still unable to match that of native cardiac tissue and many of the stem-cell derived cardiomyocytes display an immature, fetal like phenotype. In this review, we seek to elucidate the biological underpinnings of both mechanical and electrical signaling, as identified via studies related to cardiac development and those related to an evaluation of cardiac disease progression. Next, we review the different types of bioreactors developed to individually deliver electrical and mechanical stimulation to cardiomyocytes in vitro in both two and three-dimensional tissue platforms. Reactors and culture conditions that promote functional cardiomyogenesis in vitro are also highlighted. We then cover the more recent work in the development of bioreactors that combine electrical and mechanical stimulation in order to mimic the complex signaling environment present in vivo. We conclude by offering our impressions on the important next steps for physiologically relevant mechanical and electrical stimulation of cardiac cells and engineered tissue in vitro.

  9. A rare case of primary cardiac B cell lymphoma

    PubMed Central

    2014-01-01

    Primary cardiac lymphomas represent an extremely rare entity of extranodal lymphomas and should be distinguished from secondary cardiac involvement of disseminated lymphomas belonging to the non-Hodgkin’s classification of blood cancers. Only 90 cases have been reported in literature. Presentation of cardiac lymphomas on imaging studies may not be unambiguous since they potentially mimic other cardiac neoplasms including myxomas, angiosarcoma or rhadomyomas and therefore require multimodality cardiac imaging, endomyocardial biopsy, excisional intraoperative biopsy and pericardial fluid cytological evaluation to establish final diagnosis. Herein we report the case of a 70 y/o immunocompetent Caucasian female with a rapidly progressing superior vena cava syndrome secondary to a large primary cardiac diffuse large B cell lymphoma (NHL lymphoma) almost completely obstructing the right atrium, right ventricle and affecting both mitral and tricuspid valve. The patient had no clinical evidence of disseminated disease and was successfully treated with extensive debulking during open-heart surgery on cardiopulmonary bypass and 6 cycles of rituximab, cyclophosphamide, doxorubicin, vincristine and prednisone chemotherapy (R-CHOP). PMID:24422789

  10. Cardiac progenitor cells and bone marrow-derived very small embryonic-like stem cells for cardiac repair after myocardial infarction.

    PubMed

    Tang, Xian-Liang; Rokosh, D Gregg; Guo, Yiru; Bolli, Roberto

    2010-03-01

    Heart failure after myocardial infarction (MI) continues to be the most prevalent cause of morbidity and mortality worldwide. Although pharmaceutical agents and interventional strategies have contributed greatly to therapy, new and superior treatment modalities are urgently needed given the overall disease burden. Stem cell-based therapy is potentially a promising strategy to lead to cardiac repair after MI. An array of cell types has been explored in this respect, including skeletal myoblasts, bone marrow (BM)-derived stem cells, embryonic stem cells, and more recently, cardiac progenitor cells (CPCs). Recently studies have obtained evidence that transplantation of CPCs or BM-derived very small embryonic-like stem cells can improve cardiac function and alleviate cardiac remodeling, supporting the potential therapeutic utility of these cells for cardiac repair. This report summarizes the current data from those studies and discusses the potential implication of these cells in developing clinically-relevant stem cell-based therapeutic strategies for cardiac regeneration.

  11. Granule cargo release from bone marrow-derived cells sustains cardiac hypertrophy.

    PubMed

    Yang, Fanmuyi; Dong, Anping; Ahamed, Jasimuddin; Sunkara, Manjula; Smyth, Susan S

    2014-11-15

    Bone marrow-derived inflammatory cells, including platelets, may contribute to the progression of pressure overload-induced left ventricular hypertrophy (LVH). However, the underlying mechanisms for this are still unclear. One potential mechanism is through release of granule cargo. Unc13-d(Jinx) (Jinx) mice, which lack Munc13-4, a limiting factor in vesicular priming and fusion, have granule secretion defects in a variety of hematopoietic cells, including platelets. In the current study, we investigated the role of granule secretion in the development of LVH and cardiac remodeling using chimeric mice specifically lacking Munc13-4 in marrow-derived cells. Pressure overload was elicited by transverse aortic constriction (TAC). Chimeric mice were created by bone marrow transplantation. Echocardiography, histology staining, immunohistochemistry, real-time polymerase chain reaction, enzyme-linked immunosorbent assay, and mass spectrometry were used to study LVH progression and inflammatory responses. Wild-type (WT) mice that were transplanted with WT bone marrow (WT→WT) and WT mice that received Jinx bone marrow (Jinx→WT) developed LVH and a classic fetal reprogramming response early (7 days) after TAC. However, at late times (5 wk), mice lacking Munc13-4 in bone marrow-derived cells (Jinx→WT) failed to sustain the cardiac hypertrophy observed in WT chimeric mice. No difference in cardiac fibrosis was observed at early or late time points. Reinjection of WT platelets or platelet releasate partially restored cardiac hypertrophy in Jinx chimeric mice. These results suggest that sustained LVH in the setting of pressure overload depends on one or more factors secreted from bone marrow-derived cells, possibly from platelets. Inhibiting granule cargo release may represent a novel target for preventing sustained LVH.

  12. Mesenchymal Stem Cells and Inflammatory Cardiomyopathy: Cardiac Homing and Beyond

    PubMed Central

    Van Linthout, S.; Stamm, Ch.; Schultheiss, H.-P.; Tschöpe, C.

    2011-01-01

    Under conventional heart failure therapy, inflammatory cardiomyopathy usually has a progressive course, merging for alternative interventional strategies. There is accumulating support for the application of cellular transplantation as a strategy to improve myocardial function. Mesenchymal stem cells (MSCs) have the advantage over other stem cells that they possess immunomodulatory features, making them attractive candidates for the treatment of inflammatory cardiomyopathy. Studies in experimental models of inflammatory cardiomyopathy have consistently demonstrated the potential of MSCs to reduce cardiac injury and to improve cardiac function. This paper gives an overview about how inflammation triggers the functionality of MSCs and how it induces cardiac homing. Finally, the potential of intravenous application of MSCs by inflammatory cardiomyopathy is discussed. PMID:21403844

  13. Cardiac stem cell research: an elephant in the room?

    PubMed

    Di Felice, Valentina; De Luca, Angela; Colorito, Maria Luisa; Montalbano, Antonella; Ardizzone, Nella Maria; Macaluso, Filippo; Gammazza, Antonella Marino; Cappello, Francesco; Zummo, Giovanni

    2009-03-01

    Heart disease is the leading cause of death in the industrialized world, and stem cell therapy seems to be a promising treatment for injured cardiac tissue. To reach this goal, the scientific community needs to find a good source of stem cells that can be used to obtain new myocardium in a very period range of time. Since there are many ethical and technical problems with using embryonic stem cells as a source of cells with cardiogenic potential, many laboratories have attempted to isolate potential cardiac stem cells from several tissues. The best candidates seem to be cardiac "progenitor" and/or "stem" cells, which can be isolated from subendocardial biopsies from the same patient or from embryonic and/or fetal myocardium. Regardless of the technique used to isolate and characterize these cells, it appears that the different cells isolated from adult myocardium to date are all phenotypic variations of a unique cell type that expresses several markers, such as c-Kit, CD34, MDR-1, Sca-1, CD45, nestin, or Isl-1, in various combinations.

  14. Pituitary cell differentiation from stem cells and other cells: toward restorative therapy for hypopituitarism?

    PubMed

    Willems, Christophe; Vankelecom, Hugo

    2014-01-01

    The pituitary gland, key regulator of our endocrine system, produces multiple hormones that steer essential physiological processes. Hence, deficient pituitary function (hypopituitarism) leads to severe disorders. Hypopituitarism can be caused by defective embryonic development, or by damage through tumor growth/resection and traumatic brain injury. Lifelong hormone replacement is needed but associated with significant side effects. It would be more desirable to restore pituitary tissue and function. Recently, we showed that the adult (mouse) pituitary holds regenerative capacity in which local stem cells are involved. Repair of deficient pituitary may therefore be achieved by activating these resident stem cells. Alternatively, pituitary dysfunction may be mended by cell (replacement) therapy. The hormonal cells to be transplanted could be obtained by (trans-)differentiating various kinds of stem cells or other cells. Here, we summarize the studies on pituitary cell regeneration and on (trans-)differentiation toward hormonal cells, and speculate on restorative therapies for pituitary deficiency.

  15. Stem cells and molecular strategies to restore hearing

    PubMed Central

    PAULEY, S.; KOPECKY, B.; BEISEL, K.; SOUKUP, G.; FRITZSCH, B.

    2008-01-01

    Hearing loss is a costly and growing problem for the elderly population worldwide with millions of people being affected. There are currently two prosthetic devices available to minimize problems associated with the two forms of hearing loss: hearing aids that amplify sound to overcome middle ear based conductive hearing loss and cochlear implants that restore some hearing after neurosensory hearing loss. The current presentation provides information on the treatment of neurosensory hearing loss. Although the cochlear implant solution for neurosensory hearing loss is technologically advanced; it still provides only moderate hearing capacity in neurosensory deaf individuals. Inducible stem cells and molecular therapies are appealing alternatives to the cochlear implant and may provide more than a new form of treatment as they hold the promise for a cure. To this end, current insights into inducible stem cells that may provide cells for seeding the cochlea with the hope of new hair cell formation are being reviewed. Alternatively, similar to induction of stem cells, cells of the flat epithelium that remains after hair cell loss could be induced to proliferate and differentiate into hair cells. In either of these strategies, hair cell specific genes known to be essential for hair cell differentiation or maintenance such as ATOH1, POU4F3, GFI1, and miRNA-183 will be utilized with the hope of completely restoring hearing to all patients with hearing loss. PMID:18427387

  16. Cardiac stem cell therapy: Have we put too much hype in which cell type to use?

    PubMed

    Ye, Jianqin; Yeghiazarians, Yerem

    2015-09-01

    Injection of various stem cells has been tested with the hopes of improving cardiac function after a myocardial infarction (MI). However, there is continued controversy as to which cell type is best for repair. Due to technical differences in cell isolation, processing, delivery, and cardiac functional assessment by various investigators, it has been difficult to directly compare the results of different cells. Using same techniques to evaluate the efficacy of different cell types, we have separately delivered bone marrow cells (BMCs), cardiospheres (CSs), CS-derived Sca-1(+)/CD45(-) cells, human embryonic stem cell-derived cardiomyocytes, and BMC extract into infarcted murine myocardium and found that all of these treatments reduce infarct size and improve cardiac function post-MI similarly without one regimen being superior to another. The beneficial effects appear to be via paracrine influences. Different progenitors lead to improved cardiac function post-MI, but it is premature to hype any specific cell type at this time.

  17. Moxonidine modulates cytokine signalling and effects on cardiac cell viability.

    PubMed

    Aceros, Henry; Farah, Georges; Noiseux, Nicolas; Mukaddam-Daher, Suhayla

    2014-10-05

    Regression of left ventricular hypertrophy and improved cardiac function in SHR by the centrally acting imidazoline I1-receptor agonist, moxonidine, are associated with differential actions on circulating and cardiac cytokines. Herein, we investigated cell-type specific I1-receptor (also known as nischarin) signalling and the mechanisms through which moxonidine may interfere with cytokines to affect cardiac cell viability. Studies were performed on neonatal rat cardiomyocytes and fibroblasts incubated with interleukin (IL)-1β (5 ng/ml), tumor necrosis factor (TNF)-α (10 ng/ml), and moxonidine (10(-7) and 10(-5) M), separately and in combination, for 15 min, and 24 and 48 h for the measurement of MAPKs (ERK1/2, JNK, and p38) and Akt activation and inducible NOS (iNOS) expression, by Western blotting, and cardiac cell viability/proliferation and apoptosis by flow cytometry, MTT assay, and Live/Dead assay. Participation of imidazoline I1-receptors and the signalling proteins in the detected effects was identified using imidazoline I1-receptor antagonist and signalling protein inhibitors. The results show that IL-1β, and to a lower extent, TNF-α, causes cell death and that moxonidine protects against starvation- as well as IL-1β -induced mortality, mainly by maintaining membrane integrity, and in part, by improving mitochondrial activity. The protection involves activation of Akt, ERK1/2, p38, JNK, and iNOS. In contrast, moxonidine stimulates basal and IL-1β-induced fibroblast mortality by mechanisms that include inhibition of JNK and iNOS. Thus, apart from their actions on the central nervous system, imidazoline I1-receptors are directly involved in cardiac cell growth and death, and may play an important role in cardiovascular diseases associated with inflammation.

  18. Early cardiac development: a view from stem cells to embryos

    PubMed Central

    Van Vliet, Patrick; Wu, Sean M.; Zaffran, Stéphane; Pucéat, Michel

    2012-01-01

    From the 1920s, early cardiac development has been studied in chick and, later, in mouse embryos in order to understand the first cell fate decisions that drive specification and determination of the endocardium, myocardium, and epicardium. More recently, mouse and human embryonic stem cells (ESCs) have demonstrated faithful recapitulation of early cardiogenesis and have contributed significantly to this research over the past few decades. Derived almost 15 years ago, human ESCs have provided a unique developmental model for understanding the genetic and epigenetic regulation of early human cardiogenesis. Here, we review the biological concepts underlying cell fate decisions during early cardiogenesis in model organisms and ESCs. We draw upon both pioneering and recent studies and highlight the continued role for in vitro stem cells in cardiac developmental biology. PMID:22893679

  19. Nonlinear onset of calcium wave propagation in cardiac cells

    NASA Astrophysics Data System (ADS)

    Shiferaw, Yohannes

    2016-09-01

    Spontaneous calcium (Ca) waves in cardiac myocytes are known to underlie a wide range of cardiac arrhythmias. However, it is not understood which physiological parameters determine the onset of waves. In this study, we explore the relationship between Ca signaling between ion channels and the nucleation of Ca waves. In particular, we apply a master equation approach to analyze the stochastic interaction between neighboring clusters of ryanodine receptor (RyR) channels. Using this analysis, we show that signaling between clusters can be described as a barrier hopping process with exponential sensitivity to system parameters. A consequence of this feature is that the probability that Ca release at a cluster induces release at a neighboring cluster exhibits a sigmoid dependence on the Ca content in the cell. This nonlinearity originates from the regulation of RyR opening due to more than one Ca ion binding site, in conjunction with Ca mediated cooperativity between RyR channels in clusters. We apply a spatially distributed stochastic model of Ca cycling to analyze the physiological consequences of this nonlinearity, and show that it explains the sharp onset of Ca wave nucleation in cardiac cells. Furthermore, we show that this sharp onset can serve as a mechanism for Ca alternans under physiologically relevant conditions. Thus our findings identify the nonlinear features of Ca signaling which potentially underlie the onset of Ca waves and Ca alternans in cardiac cells.

  20. iPS cells: a source of cardiac regeneration.

    PubMed

    Yoshida, Yoshinori; Yamanaka, Shinya

    2011-02-01

    For the treatment of heart failure, a new strategy to improve cardiac function and inhibit cardiac remodeling needs to be established. Embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs) are pluripotent cells that can differentiate into cell types from all three germ layers both in vitro and in vivo. The therapeutic effect of ES/iPS cell-derived progeny was reported in animal model. Mouse and human somatic cells can be reprogrammed to induced pluripotent stem cells (iPSCs) by the transduction of four transcription factors, Oct 3/4, Sox2, Klf4, and c-Myc. However, the low induction efficiency hinders the clinical application of iPS technology, and efforts have been made to improve the reprogramming efficiency. There are variations in the characteristics in ES/iPS cell lines, and the further understanding is necessary for the applications of ES/iPS cell technology. Some improvements were also made in the methods to induce cardiomyocytes from ES/iPS cells efficiently. This review article is focused on generation of iPS cells, cardiomyocyte differentiation from ES/iPS cells, and transplantation of derived cardiomyocytes.This article is part of a special issue entitled, "Cardiovascular Stem Cells Revisited".

  1. Electrical stimulation of cardiac adipose tissue-derived progenitor cells modulates cell phenotype and genetic machinery.

    PubMed

    Llucià-Valldeperas, A; Sanchez, B; Soler-Botija, C; Gálvez-Montón, C; Prat-Vidal, C; Roura, S; Rosell-Ferrer, J; Bragos, R; Bayes-Genis, A

    2015-11-01

    A major challenge of cardiac tissue engineering is directing cells to establish the physiological structure and function of the myocardium being replaced. Our aim was to examine the effect of electrical stimulation on the cardiodifferentiation potential of cardiac adipose tissue-derived progenitor cells (cardiac ATDPCs). Three different electrical stimulation protocols were tested; the selected protocol consisted of 2 ms monophasic square-wave pulses of 50 mV/cm at 1 Hz over 14 days. Cardiac and subcutaneous ATDPCs were grown on biocompatible patterned surfaces. Cardiomyogenic differentiation was examined by real-time PCR and immunocytofluorescence. In cardiac ATDPCs, MEF2A and GATA-4 were significantly upregulated at day 14 after stimulation, while subcutaneous ATDPCs only exhibited increased Cx43 expression. In response to electrical stimulation, cardiac ATDPCs elongated, and both cardiac and subcutaneous ATDPCs became aligned following the linear surface pattern of the construct. Cardiac ATDPC length increased by 11.3%, while subcutaneous ATDPC length diminished by 11.2% (p = 0.013 and p = 0.030 vs unstimulated controls, respectively). Compared to controls, electrostimulated cells became aligned better to the patterned surfaces when the pattern was perpendicular to the electric field (89.71 ± 28.47º for cardiac ATDPCs and 92.15 ± 15.21º for subcutaneous ATDPCs). Electrical stimulation of cardiac ATDPCs caused changes in cell phenotype and genetic machinery, making them more suitable for cardiac regeneration approaches. Thus, it seems advisable to use electrical cell training before delivery as a cell suspension or within engineered tissue.

  2. SPARC regulates collagen interaction with cardiac fibroblast cell surfaces.

    PubMed

    Harris, Brett S; Zhang, Yuhua; Card, Lauren; Rivera, Lee B; Brekken, Rolf A; Bradshaw, Amy D

    2011-09-01

    Cardiac tissue from mice that do not express secreted protein acidic and rich in cysteine (SPARC) have reduced amounts of insoluble collagen content at baseline and in response to pressure overload hypertrophy compared with wild-type (WT) mice. However, the cellular mechanism by which SPARC affects myocardial collagen is not clearly defined. Although expression of SPARC by cardiac myocytes has been detected in vitro, immunohistochemistry of hearts demonstrated SPARC staining primarily associated with interstitial fibroblastic cells. Primary cardiac fibroblasts isolated from SPARC-null and WT mice were assayed for collagen I synthesis by [(3)H]proline incorporation into procollagen and by immunoblot analysis of procollagen processing. Bacterial collagenase was used to discern intracellular from extracellular forms of collagen I. Increased amounts of collagen I were found associated with SPARC-null versus WT cells, and the proportion of total collagen I detected on SPARC-null fibroblasts without propeptides [collagen-α(1)(I)] was higher than in WT cells. In addition, the amount of total collagen sensitive to collagenase digestion (extracellular) was greater in SPARC-null cells than in WT cells, indicating an increase in cell surface-associated collagen in the absence of SPARC. Furthermore, higher levels of collagen type V, a fibrillar collagen implicated in collagen fibril initiation, were found in SPARC-null fibroblasts. The absence of SPARC did not result in significant differences in proliferation or in decreased production of procollagen I by cardiac fibroblasts. We conclude that SPARC regulates collagen in the heart by modulating procollagen processing and interactions with fibroblast cell surfaces. These results are consistent with decreased levels of interstitial collagen in the hearts of SPARC-null mice being due primarily to inefficient collagen deposition into the extracellular matrix rather than to differences in collagen production.

  3. Modern Perspectives on Numerical Modeling of Cardiac Pacemaker Cell

    PubMed Central

    Maltsev, Victor A.; Yaniv, Yael; Maltsev, Anna V.; Stern, Michael D.; Lakatta, Edward G.

    2015-01-01

    Cardiac pacemaking is a complex phenomenon that is still not completely understood. Together with experimental studies, numerical modeling has been traditionally used to acquire mechanistic insights in this research area. This review summarizes the present state of numerical modeling of the cardiac pacemaker, including approaches to resolve present paradoxes and controversies. Specifically we discuss the requirement for realistic modeling to consider symmetrical importance of both intracellular and cell membrane processes (within a recent “coupled-clock” theory). Promising future developments of the complex pacemaker system models include the introduction of local calcium control, mitochondria function, and biochemical regulation of protein phosphorylation and cAMP production. Modern numerical and theoretical methods such as multi-parameter sensitivity analyses within extended populations of models and bifurcation analyses are also important for the definition of the most realistic parameters that describe a robust, yet simultaneously flexible operation of the coupled-clock pacemaker cell system. The systems approach to exploring cardiac pacemaker function will guide development of new therapies, such as biological pacemakers for treating insufficient cardiac pacemaker function that becomes especially prevalent with advancing age. PMID:24748434

  4. Optical Imaging of Voltage and Calcium in Cardiac Cells & Tissues

    PubMed Central

    Herron, Todd J.; Lee, Peter; Jalife, José

    2012-01-01

    Cardiac optical mapping has proven to be a powerful technology for studying cardiovascular function and disease. The development and scientific impact of this methodology are well documented. Because of its relevance in cardiac research, this imaging technology advances at a rapid pace. Here we review technological and scientific developments during the past several years and look also towards the future. First we explore key components of a modern optical mapping setup, focusing on 1) new camera technologies, 2) powerful light-emitting-diodes (from ultraviolet to red) for illumination, 3) improved optical filter technology, 4) new synthetic and optogenetic fluorescent probes, 5) optical mapping with motion and contraction, 6) new multi-parametric optical mapping techniques and 7) photon scattering effects in thick tissue preparations. We then look at recent optical mapping studies in single cells, cardiomyocyte monolayers, atria and whole hearts. Finally, we briefly look into the possible future roles of optical mapping in the development of regenerative cardiac research, cardiac cell therapies, and molecular genetic advances. PMID:22343556

  5. Epigenomic Reprogramming of Adult Cardiomyocyte-Derived Cardiac Progenitor Cells

    PubMed Central

    Zhang, Yiqiang; Zhong, Jiang F; Qiu, Hongyu; Robb MacLellan, W.; Marbán, Eduardo; Wang, Charles

    2015-01-01

    It has been believed that mammalian adult cardiomyocytes (ACMs) are terminally-differentiated and are unable to proliferate. Recently, using a bi-transgenic ACM fate mapping mouse model and an in vitro culture system, we demonstrated that adult mouse cardiomyocytes were able to dedifferentiate into cardiac progenitor-like cells (CPCs). However, little is known about the molecular basis of their intrinsic cellular plasticity. Here we integrate single-cell transcriptome and whole-genome DNA methylation analyses to unravel the molecular mechanisms underlying the dedifferentiation and cell cycle reentry of mouse ACMs. Compared to parental cardiomyocytes, dedifferentiated mouse cardiomyocyte-derived CPCs (mCPCs) display epigenomic reprogramming with many differentially-methylated regions, both hypermethylated and hypomethylated, across the entire genome. Correlated well with the methylome, our transcriptomic data showed that the genes encoding cardiac structure and function proteins are remarkably down-regulated in mCPCs, while those for cell cycle, proliferation, and stemness are significantly up-regulated. In addition, implantation of mCPCs into infarcted mouse myocardium improves cardiac function with augmented left ventricular ejection fraction. Our study demonstrates that the cellular plasticity of mammalian cardiomyocytes is the result of a well-orchestrated epigenomic reprogramming and a subsequent global transcriptomic alteration. PMID:26657817

  6. Concise Review: Skeletal Muscle Stem Cells and Cardiac Lineage: Potential for Heart Repair

    PubMed Central

    Hassan, Narmeen; Tchao, Jason

    2014-01-01

    Valuable and ample resources have been spent over the last two decades in pursuit of interventional strategies to treat the unmet demand of heart failure patients to restore myocardial structure and function. At present, it is clear that full restoration of myocardial structure and function is outside our reach from both clinical and basic research studies, but it may be achievable with a combination of ongoing research, creativity, and perseverance. Since the 1990s, skeletal myoblasts have been extensively investigated for cardiac cell therapy of congestive heart failure. Whereas the Myoblast Autologous Grafting in Ischemic Cardiomyopathy (MAGIC) trial revealed that transplanted skeletal myoblasts did not integrate into the host myocardium and also did not transdifferentiate into cardiomyocytes despite some beneficial effects on recipient myocardial function, recent studies suggest that skeletal muscle-derived stem cells have the ability to adopt a cardiomyocyte phenotype in vitro and in vivo. This brief review endeavors to summarize the importance of skeletal muscle stem cells and how they can play a key role to surpass current results in the future and enhance the efficacious implementation of regenerative cell therapy for heart failure. PMID:24371329

  7. Stem Cells for Cardiac Regeneration by Cell Therapy and Myocardial Tissue Engineering

    NASA Astrophysics Data System (ADS)

    Wu, Jun; Zeng, Faquan; Weisel, Richard D.; Li, Ren-Ke

    Congestive heart failure, which often occurs progressively following a myocardial infarction, is characterized by impaired myocardial perfusion, ventricular dilatation, and cardiac dysfunction. Novel treatments are required to reverse these effects - especially in older patients whose endogenous regenerative responses to currently available therapies are limited by age. This review explores the current state of research for two related approaches to cardiac regeneration: cell therapy and tissue engineering. First, to evaluate cell therapy, we review the effectiveness of various cell types for their ability to limit ventricular dilatation and promote functional recovery following implantation into a damaged heart. Next, to assess tissue engineering, we discuss the characteristics of several biomaterials for their potential to physically support the infarcted myocardium and promote implanted cell survival following cardiac injury. Finally, looking ahead, we present recent findings suggesting that hybrid constructs combining a biomaterial with stem and supporting cells may be the most effective approaches to cardiac regeneration.

  8. Stem cells for cardiac regeneration by cell therapy and myocardial tissue engineering.

    PubMed

    Wu, Jun; Zeng, Faquan; Weisel, Richard D; Li, Ren-Ke

    2009-01-01

    Congestive heart failure, which often occurs progressively following a myocardial infarction, is characterized by impaired myocardial perfusion, ventricular dilatation, and cardiac dysfunction. Novel treatments are required to reverse these effects - especially in older patients whose endogenous regenerative responses to currently available therapies are limited by age. This review explores the current state of research for two related approaches to cardiac regeneration: cell therapy and tissue engineering. First, to evaluate cell therapy, we review the effectiveness of various cell types for their ability to limit ventricular dilatation and promote functional recovery following implantation into a damaged heart. Next, to assess tissue engineering, we discuss the characteristics of several biomaterials for their potential to physically support the infarcted myocardium and promote implanted cell survival following cardiac injury. Finally, looking ahead, we present recent findings suggesting that hybrid constructs combining a biomaterial with stem and supporting cells may be the most effective approaches to cardiac regeneration.

  9. Harnessing the secretome of cardiac stem cells as therapy for ischemic heart disease.

    PubMed

    Khanabdali, Ramin; Rosdah, Ayeshah A; Dusting, Gregory J; Lim, Shiang Y

    2016-08-01

    Adult stem cells continue to promise opportunities to repair damaged cardiac tissue. However, precisely how adult stem cells accomplish cardiac repair, especially after ischemic damage, remains controversial. It has been postulated that the clinical benefit of adult stem cells for cardiovascular disease results from the release of cytokines and growth factors by the transplanted cells. Studies in animal models of myocardial infarction have reported that such paracrine factors released from transplanted adult stem cells contribute to improved cardiac function by several processes. These include promoting neovascularization of damaged tissue, reducing inflammation, reducing fibrosis and scar formation, as well as protecting cardiomyocytes from apoptosis. In addition, these factors might also stimulate endogenous repair by activating cardiac stem cells. Interestingly, stem cells discovered to be resident in the heart appear to be functionally superior to extra-cardiac adult stem cells when transplanted for cardiac repair and regeneration. In this review, we discuss the therapeutic potential of cardiac stem cells and how the proteins secreted from these cells might be harnessed to promote repair and regeneration of damaged cardiac tissue. We also highlight how recent controversies about the efficacy of adult stem cells in clinical trials of ischemic heart disease have not dampened enthusiasm for the application of cardiac stem cells and their paracrine factors for cardiac repair: the latter have proved superior to the mesenchymal stem cells used in most clinical trials in the past, some of which appear to have been conducted with sub-optimal rigor.

  10. Quality Metrics for Stem Cell-Derived Cardiac Myocytes

    PubMed Central

    Sheehy, Sean P.; Pasqualini, Francesco; Grosberg, Anna; Park, Sung Jin; Aratyn-Schaus, Yvonne; Parker, Kevin Kit

    2014-01-01

    Summary Advances in stem cell manufacturing methods have made it possible to produce stem cell-derived cardiac myocytes at industrial scales for in vitro muscle physiology research purposes. Although FDA-mandated quality assurance metrics address safety issues in the manufacture of stem cell-based products, no standardized guidelines currently exist for the evaluation of stem cell-derived myocyte functionality. As a result, it is unclear whether the various stem cell-derived myocyte cell lines on the market perform similarly, or whether any of them accurately recapitulate the characteristics of native cardiac myocytes. We propose a multiparametric quality assessment rubric in which genetic, structural, electrophysiological, and contractile measurements are coupled with comparison against values for these measurements that are representative of the ventricular myocyte phenotype. We demonstrated this procedure using commercially available, mass-produced murine embryonic stem cell- and induced pluripotent stem cell-derived myocytes compared with a neonatal mouse ventricular myocyte target phenotype in coupled in vitro assays. PMID:24672752

  11. [Embryonic stem cells in the treatment of severe cardiac insufficiency].

    PubMed

    Menasché, Philippe

    2012-01-01

    The experience accumulated in cardiac cell therapy suggests that regeneration of extensively necrotic myocardial areas is unlikely to be achieved by the sole paracrine effects of the grafted cells but rather requires the conversion of these cells into cardiomyocytes featuring the capacity to substitute for those which have been irreversibly lost. In this setting, the use of human pluripotent embryonic stem cells has a strong rationale. The experimental results obtained in animal models of myocardial infarction are encouraging. However, the switch to clinical applications still requires to address some critical issues, among which optimizing cardiac specification of the embryonic stem cells, purifying the resulting progenitor cells so as to graft a purified population devoid from any contamination by residual pluripotent cells which carry the risk of tumorigenesis and controlling the expected allogeneic rejection by clinically acceptable methods. If the solution to these problems is a pre-requisite, the therapeutic success of this approach will also depend on the capacity to efficiently transfer the cells to the target tissue, to keep them alive once engrafted and to allow them to spatially organize in such a way that they can contribute to the contractile function of the heart.

  12. Integrative Modeling of Electrical Properties of Pacemaker Cardiac Cells

    NASA Astrophysics Data System (ADS)

    Grigoriev, M.; Babich, L.

    2016-06-01

    This work represents modeling of electrical properties of pacemaker (sinus) cardiac cells. Special attention is paid to electrical potential arising from transmembrane current of Na+, K+ and Ca2+ ions. This potential is calculated using the NaCaX model. In this respect, molar concentration of ions in the intercellular space which is calculated on the basis of the GENTEX model is essential. Combined use of two different models allows referring this approach to integrative modeling.

  13. Cardiac Repair and Regeneration: The Value of Cell Therapies.

    PubMed

    Lerman, Daniel Alejandro; Alotti, Nasri; Ume, Kiddy Levente; Péault, Bruno

    2016-01-01

    Ischaemic heart disease is the predominant contributor to cardiovascular morbidity and mortality; one million myocardial Infarctions occur per year in the USA, while more than five million patients suffer from chronic heart failure. Recently, heart failure has been singled out as an epidemic and is a staggering clinical and public health problem associated with significant mortality, morbidity and healthcare expenditures, particularly among those aged ≥65 years. Death rates have improved dramatically over the last four decades, but new approaches are nevertheless urgently needed for those patients who go on to develop ventricular dysfunction and chronic heart failure. Over the past decade, stem cell transplantation has emerged as a promising therapeutic strategy for acute or chronic ischaemic cardiomyopathy. Multiple candidate cell types have been used in preclinical animal models and in humans to repair or regenerate the injured heart, either directly or indirectly (through paracrine effects), including: embryonic stem cells (ESCs), induced pluripotent stem cells (iPSCs), neonatal cardiomyocytes, skeletal myoblasts (SKMs), endothelial progenitor cells, bone marrow mononuclear cells (BMMNCs), mesenchymal stem cells (MSCs) and, most recently, cardiac stem cells (CSCs). Although no consensus has emerged yet, the ideal cell type for the treatment of heart disease should: (a) improve heart function; (b) create healthy and functional cardiac muscle and vasculature, integrated into the host tissue; (c) be amenable to delivery by minimally invasive clinical methods; (d) be available 'off the shelf' as a standardised reagent; (e) be tolerated by the immune system; (f) be safe oncologically, i.e. not create tumours; and (g) circumvent societal ethical concerns. At present, it is not clear whether such a 'perfect' stem cell exists; what is apparent, however, is that some cell types are more promising than others. In this brief review, we provide ongoing data on agreement

  14. Calcium Imaging in Pluripotent Stem Cell-Derived Cardiac Myocytes.

    PubMed

    Walter, Anna; Šarić, Tomo; Hescheler, Jürgen; Papadopoulos, Symeon

    2016-01-01

    The possibility to generate cardiomyocytes (CMs) from disease-specific induced pluripotent stem cells (iPSCs) is a powerful tool for the investigation of various cardiac diseases in vitro. The pathological course of various cardiac conditions, causatively heterogeneous, often converges into disturbed cellular Ca(2+) cycling. The gigantic Ca(2+) channel of the intracellular Ca(2+) store of CMs, the ryanodine receptor type 2 (RyR2), controls Ca(2+) release and therefore plays a crucial role in Ca(2+) cycling of CMs. In the present protocol we describe ways to measure and analyze global as well as local cellular Ca(2+) release events in CMs derived from a patient carrying a CPVT-causing RyR2 mutation.

  15. The developing role of Neuregulin1 in cardiac regenerative stem cell therapy.

    PubMed

    P Blomberg, Christopher; Lee, Juyong; P Morgan, James

    2014-01-01

    Myocardial infarction, heart failure, and chronic ischemic heart disease account for the majority of the cardiovascular burden. The current treatment strategies focus on limiting the progression of disease and preserving cardiac myocardium. The goal of stem cell therapy, on the other hand, is to reverse or replace damaged cardiac tissue. Over the past two decades many studies have been conducted to understand stem cell performance, survival, and the potential for cardiac repair. Neuregulin1, an epidermal growth factor family member, promotes embryonic stem cell differentiation into the cardiac lineage and improves survival in bone marrow-derived mesenchymal stem cell and embryonic endothelial progenitor cells. Current clinical trials are actively pursuing Neuregulin1's therapeutic potential in the areas of heart failure and cardiac ischemia. It is the intent of this paper to review the current knowledge of Neuregulin1 in stem cell biology and discuss the potential of using Neuregulin1 to improve stem cell therapy for cardiac repair.

  16. Cardiac stem cell therapy and arrhythmogenicity: prometheus and the arrows of Apollo and Artemis.

    PubMed

    Lyon, Alexander R; Harding, Sian E; Peters, Nicholas S

    2008-09-01

    Cardiac cell therapy is an expanding scientific field which is yielding new insights into the pathogenesis of cardiac disease and offers new therapeutic strategies. Inherent to both these areas of research are the electrical properties of individual cells, the electrical interplay between cardiomyocytes, and their roles in arrhythmogenesis. This review discusses the potential mechanisms by which various candidate cells for cardiac therapy may modulate the ventricular arrhythmic substrate and highlights the data and lessons learnt from the clinical cardiac cell therapy trials published to date. Pro- and antiarrhythmic mechanistic factors are discussed, and the importance of their consideration in the design of any future clinical cell therapy trials.

  17. Patient-Specific Induced Pluripotent Stem Cell Models: Generation and Characterization of Cardiac Cells.

    PubMed

    Zanella, Fabian; Sheikh, Farah

    2016-01-01

    The generation of human induced pluripotent stem cell (hiPSC)-derived cardiomyocytes has been of utmost interest for the study of cardiac development, cardiac disease modeling, and evaluation of cardiotoxic effects of novel candidate drugs. Several protocols have been developed to guide human stem cells toward the cardiogenic path. Pioneering work used serum to promote cardiogenesis; however, low cardiogenic throughputs, lack of chemical definition, and batch-to-batch variability of serum lots constituted a considerable impediment to the implementation of those protocols to large-scale cell biology. Further work focused on the manipulation of pathways that mouse genetics indicated to be fundamental in cardiac development to promote cardiac differentiation in stem cells. Although extremely elegant, those serum-free protocols involved the use of human recombinant cytokines that tend to be quite costly and which can also be variable between lots. The latest generation of cardiogenic protocols aimed for a more cost-effective and reproducible definition of the conditions driving cardiac differentiation, using small molecules to manipulate cardiogenic pathways overriding the need for cytokines. This chapter details methods based on currently available cardiac differentiation protocols for the generation and characterization of robust numbers of hiPSC-derived cardiomyocytes under chemically defined conditions.

  18. Patient-Specific Induced Pluripotent Stem Cell Models: Generation and Characterization of Cardiac Cells

    PubMed Central

    Zanella, Fabian; Sheikh, Farah

    2017-01-01

    The generation of human induced pluripotent stem cell (hiPSC)-derived cardiomyocytes has been of utmost interest for the study of cardiac development, cardiac disease modeling, and evaluation of cardiotoxic effects of novel candidate drugs. Several protocols have been developed to guide human stem cells toward the cardiogenic path. Pioneering work used serum to promote cardiogenesis; however, low cardiogenic throughputs, lack of chemical definition, and batch-to-batch variability of serum lots constituted a considerable impediment to the implementation of those protocols to large-scale cell biology. Further work focused on the manipulation of pathways that mouse genetics indicated to be fundamental in cardiac development to promote cardiac differentiation in stem cells. Although extremely elegant, those serum-free protocols involved the use of human recombinant cytokines that tend to be quite costly and which can also be variable between lots. The latest generation of cardiogenic protocols aimed for a more cost-effective and reproducible definition of the conditions driving cardiac differentiation, using small molecules to manipulate cardiogenic pathways overriding the need for cytokines. This chapter details methods based on currently available cardiac differentiation protocols for the generation and characterization of robust numbers of hiPSC-derived cardiomyocytes under chemically defined conditions. PMID:25520292

  19. Uniform sarcomere shortening behavior in isolated cardiac muscle cells

    PubMed Central

    1980-01-01

    We have observed the dynamics of sarcomere shortening and the diffracting action of single, functionally intact, unattached cardiac muscle cells enzymatically isolated from the ventricular tissue of adult rats. Sarcomere length was measured either (a) continuously by a light diffraction method or (b) by direct inspection of the cell's striated image as recorded on videotape or by cinemicroscopy (120--400 frames/s). At physiological levels of added CaCl2 (0.5--2.0 mM), many cells were quiescent (i.e., they did not beat spontaneously) and contracted in response to electrical stimulation (less than or equal to 1.0-ms pulse width). Sarcomere length in the quiescent, unstimulated cells (1.93 +/- 0.10 [SD] micrometers), at peak shortening (1.57 +/- 0.13 micrometers, n = 49), and the maximum velocity of sarcomere shortening and relengthening were comparable to previous observations in intact heart muscle preparations. The dispersion of light diffracted by the cell remained narrow, and individual striations remained distinct and laterally well registered throughout the shortening- relengthening cycle. In contrast, appreciable nonuniformity and internal buckling were seen at sarcomere lengths < 1.8 micrometers when the resting cell, embedded in gelatin, was longitudinally compressed These results indicate (a) that shortening and relengthening is characterized by uniform activation between myofibrils within the cardiac cell and (b) that physiologically significant relengthening forces in living heart muscle originate at the level of the cell rather than in extracellular connections. First-order diffracted light intensity, extremely variable during sarcomere shortening, was always greatest during midrelaxation preceding the onset of a very slow and uniform phase of sarcomere relengthening. PMID:7441197

  20. Perspectives on stem cell therapy for cardiac regeneration. Advances and challenges.

    PubMed

    Choi, Sung Hyun; Jung, Seok Yun; Kwon, Sang-Mo; Baek, Sang Hong

    2012-01-01

    Ischemic heart disease (IHD) accelerates cardiomyocyte loss, but the developing stem cell research could be useful for regenerating a variety of tissue cells, including cardiomyocytes. Diverse sources of stem cells for IHD have been reported, including embryonic stem cells, induced pluripotent stem cells, skeletal myoblasts, bone marrow-derived stem cells, mesenchymal stem cells, and cardiac stem cells. However, stem cells have unique advantages and disadvantages for cardiac tissue regeneration, which are important considerations in determining the specific cells for improving cell survival and long-term engraftment after transplantation. Additionally, the dosage and administration method of stem cells need to be standardized to increase stability and efficacy for clinical applications. Accordingly, this review presents a summary of the stem cell therapies that have been studied for cardiac regeneration thus far, and discusses the direction of future cardiac regeneration research for stem cells.

  1. Cell-cell junction remodeling in the heart: possible role in cardiac conduction system function and arrhythmias?

    PubMed

    Mezzano, Valeria; Sheikh, Farah

    2012-02-27

    Anchoring cell-cell junctions (desmosomes, fascia adherens) play crucial roles in maintaining mechanical integrity of cardiac muscle cells and tissue. Genetic mutations and/or loss of critical components in these macromolecular structures are increasingly being associated with arrhythmogenic cardiomyopathies; however, their specific roles have been primarily attributed to effects within the working (ventricular) cardiac muscle. Growing evidence also points to a key role for anchoring cell-cell junction components in cardiac muscle cells of the cardiac conduction system. This is not only evidenced by the molecular and ultra-structural presence of anchoring cell junctions in specific compartments/structures of the cardiac conduction system (sinoatrial node, atrioventricular node, His-Purkinje system), but also because conduction system-related arrhythmias can be found in humans and mouse models of cardiomyopathies harboring defects and/or mutations in key anchoring cell-cell junction proteins. These studies emphasize the clinical need to understand the molecular and cellular role(s) for anchoring cell-cell junctions in cardiac conduction system function and arrhythmias. This review will focus on (i) experimental findings that underline an important role for anchoring cell-cell junctions in the cardiac conduction system, (ii) insights regarding involvement of these structures in age-related cardiac remodeling of the conduction system, (iii) summarizing available genetic mouse models that can target cardiac conduction system structures and (iv) implications of these findings on future therapies for arrhythmogenic heart diseases.

  2. SUCCESSFUL FERTILITY RESTORATION AFTER ALLOGENEIC HEMATOPOIETIC STEM CELL TRANSPLANTATION

    PubMed Central

    Gharwan, Helen; Neary, Nicola M.; Link, Mary; Hsieh, Matthew M.; Fitzhugh, Courtney D.; Sherins, Richard J.; Tisdale, John F.

    2015-01-01

    Objective Myeloablative conditioning regimens given prior to hematopoietic stem cell transplantation (HSCT) frequently cause permanent sterility in men. In patients with sickle cell disease (SCD) we use a nonmyeloablative regimen with sirolimus, alemtuzumab, and low-dose total-body irradiation (300 centigrays) with gonadal shielding preceding allogeneic HSCT. We report here the restoration of azoospermia in a patient with SCD after allogeneic HSCT. We discuss the impact of our patient’s underlying chronic medical conditions and the therapies he had received (frequent blood transfusions, iron chelating drugs, ribavirin, hydroxyurea, opioids), as well as the impact of the nonmyeloablative conditioning regimen on male gonadal function, and we review the literature on this topic. Methods We determined the patient’s reproductive hormonal values and his semen parameters before, during, and after HSCT and infertility treatment. In addition, we routinely measured his serum laboratory parameters pertinent to SCD and infertility, such as iron and ferritin levels. A karyotype analysis was performed to assess the potential presence of Klinefelter syndrome. Finally, imaging studies of the patient’s brain and testes were done to rule out further underlying pathology. Results A 42-year-old man with SCD, transfusional iron overload, and hepatitis C underwent a nonmyeloablative allogeneic HSCT. One year later he desired to father a child but was found to be azoospermic in the context of hypogonadotropic hypogonadism. Restoration of fertility was attempted with human chorionic gonadotropin (2,000 IU) plus human menopausal gonadotropin (75 IU follicle-stimulating hormone) injected subcutaneously 3 times weekly. Within 6 months of treatment, the patient’s serum calculated free testosterone value normalized, and his sperm count and sperm motility improved. After 10 months, he successfully initiated a pregnancy through intercourse. The pregnancy was uncomplicated, and a healthy

  3. The Role of MicroRNAs in Cardiac Stem Cells

    PubMed Central

    Purvis, Nima; Bahn, Andrew; Katare, Rajesh

    2015-01-01

    Stem cells are considered as the next generation drug treatment in patients with cardiovascular disease who are resistant to conventional treatment. Among several stem cells used in the clinical setting, cardiac stem cells (CSCs) which reside in the myocardium and epicardium of the heart have been shown to be an effective option for the source of stem cells. In normal circumstances, CSCs primarily function as a cell store to replace the physiologically depleted cardiovascular cells, while under the diseased condition they have been shown to experimentally regenerate the diseased myocardium. In spite of their major functional role, molecular mechanisms regulating the CSCs proliferation and differentiation are still unknown. MicroRNAs (miRs) are small, noncoding RNA molecules that regulate gene expression at the posttranscriptional level. Recent studies have demonstrated the important role of miRs in regulating stem cell proliferation and differentiation, as well as other physiological and pathological processes related to stem cell function. This review summarises the current understanding of the role of miRs in CSCs. A deeper understanding of the mechanisms by which miRs regulate CSCs may lead to advances in the mode of stem cell therapies for the treatment of cardiovascular diseases. PMID:25802528

  4. Stem cell therapy for cardiac regeneration: hits and misses.

    PubMed

    Padda, Jagjit; Sequiera, Glen Lester; Sareen, Niketa; Dhingra, Sanjiv

    2015-10-01

    Cardiac injury and loss of cardiomyocytes is a causative as well as a resultant condition of cardiovascular disorders, which are the leading cause of death throughout the world. This loss of cardiomyocytes cannot be completely addressed through the currently available drugs being administered, which mainly function only in relieving the symptoms. There is a huge potential being investigated for regenerative and cell replacement therapies through recruiting stem cells of various origins namely embryonic, reprogramming/induction, and adult tissue. These sources are being actively studied for translation to clinical scenarios. In this review, we attempt to discuss some of these promising scenarios, including the clinical trials and the obstacles that need to be overcome, and hope to address the direction in which stem cell therapy is heading.

  5. Targeting Dendritic Cell Function during Systemic Autoimmunity to Restore Tolerance

    PubMed Central

    Mackern-Oberti, Juan P.; Vega, Fabián; Llanos, Carolina; Bueno, Susan M.; Kalergis, Alexis M.

    2014-01-01

    Systemic autoimmune diseases can damage nearly every tissue or cell type of the body. Although a great deal of progress has been made in understanding the pathogenesis of autoimmune diseases, current therapies have not been improved, remain unspecific and are associated with significant side effects. Because dendritic cells (DCs) play a major role in promoting immune tolerance against self-antigens (self-Ags), current efforts are focusing at generating new therapies based on the transfer of tolerogenic DCs (tolDCs) during autoimmunity. However, the feasibility of this approach during systemic autoimmunity has yet to be evaluated. TolDCs may ameliorate autoimmunity mainly by restoring T cell tolerance and, thus, indirectly modulating autoantibody development. In vitro induction of tolDCs loaded with immunodominant self-Ags and subsequent cell transfer to patients would be a specific new therapy that will avoid systemic immunosuppression. Herein, we review recent approaches evaluating the potential of tolDCs for the treatment of systemic autoimmune disorders. PMID:25229821

  6. Scaffold Free Bio-orthogonal Assembly of 3-Dimensional Cardiac Tissue via Cell Surface Engineering

    PubMed Central

    Rogozhnikov, Dmitry; O’Brien, Paul J.; Elahipanah, Sina; Yousaf , Muhammad N.

    2016-01-01

    There has been tremendous interest in constructing in vitro cardiac tissue for a range of fundamental studies of cardiac development and disease and as a commercial system to evaluate therapeutic drug discovery prioritization and toxicity. Although there has been progress towards studying 2-dimensional cardiac function in vitro, there remain challenging obstacles to generate rapid and efficient scaffold-free 3-dimensional multiple cell type co-culture cardiac tissue models. Herein, we develop a programmed rapid self-assembly strategy to induce specific and stable cell-cell contacts among multiple cell types found in heart tissue to generate 3D tissues through cell-surface engineering based on liposome delivery and fusion to display bio-orthogonal functional groups from cell membranes. We generate, for the first time, a scaffold free and stable self assembled 3 cell line co-culture 3D cardiac tissue model by assembling cardiomyocytes, endothelial cells and cardiac fibroblast cells via a rapid inter-cell click ligation process. We compare and analyze the function of the 3D cardiac tissue chips with 2D co-culture monolayers by assessing cardiac specific markers, electromechanical cell coupling, beating rates and evaluating drug toxicity. PMID:28008983

  7. Cardiac muscle plasticity in adult and embryo by heart-derived progenitor cells.

    PubMed

    Oh, Hidemasa; Chi, Xuan; Bradfute, Steven B; Mishina, Yuji; Pocius, Jennifer; Michael, Lloyd H; Behringer, Richard R; Schwartz, Robert J; Entman, Mark L; Schneider, Michael D

    2004-05-01

    The evidence of cardiomyocyte proliferation in damaged heart implied cardiac regeneration might occur by resident or extra cardiac stem cells. However, the specification and origin of these cells remain unknown. Here, we report using fluorescence-activated cell sorting that cardiac progenitor cells resided in adult heart and colocalized with small capillary vessels, within the stem cell antigen (Sca-1) population expressing high telomerase activity. Notably, hematopoietic stem cells capable of efflux Hoechst 33342, termed side population cells, also were identified within the heart-derived cells. The cardiac progenitor cells (CD45(-)/CD34(-)) express neither cardiac muscle nor endothelial cell markers at an undifferentiated stage. The exposure of 5-azacytidine induced cardiac differentiation, which depends, in part, on Bmpr1a, a type IA receptor for bone morphogenetic protein (BMP). The capability of adult Sca1(+) cells to adopt a cardiac muscle in embryogenesis was substantiated by blastocyst injection, using progenitors from the adult hearts of transgenic mice that harbor a bacterial artificial chromosome expressing GFP via the Nkx-2.5 locus. Intravenously injected progenitors, shortly after ischemic/reperfusion, homed and functionally differentiated 3.5% of total left ventricle in the host myocardium. Differentiation included both fusion-independent and fusion-associated components, proved by the Cre/loxP donor/recipient system. Our studies suggest that endogenous cardiac progenitors reside in the adult heart, regenerate cardiomyocytes functionally, and integrate into the existing heart circuitry.

  8. Scaffold Free Bio-orthogonal Assembly of 3-Dimensional Cardiac Tissue via Cell Surface Engineering

    NASA Astrophysics Data System (ADS)

    Rogozhnikov, Dmitry; O’Brien, Paul J.; Elahipanah, Sina; Yousaf, Muhammad N.

    2016-12-01

    There has been tremendous interest in constructing in vitro cardiac tissue for a range of fundamental studies of cardiac development and disease and as a commercial system to evaluate therapeutic drug discovery prioritization and toxicity. Although there has been progress towards studying 2-dimensional cardiac function in vitro, there remain challenging obstacles to generate rapid and efficient scaffold-free 3-dimensional multiple cell type co-culture cardiac tissue models. Herein, we develop a programmed rapid self-assembly strategy to induce specific and stable cell-cell contacts among multiple cell types found in heart tissue to generate 3D tissues through cell-surface engineering based on liposome delivery and fusion to display bio-orthogonal functional groups from cell membranes. We generate, for the first time, a scaffold free and stable self assembled 3 cell line co-culture 3D cardiac tissue model by assembling cardiomyocytes, endothelial cells and cardiac fibroblast cells via a rapid inter-cell click ligation process. We compare and analyze the function of the 3D cardiac tissue chips with 2D co-culture monolayers by assessing cardiac specific markers, electromechanical cell coupling, beating rates and evaluating drug toxicity.

  9. Mesenchymal Stem Cells for Cardiac Regenerative Therapy: Optimization of Cell Differentiation Strategy.

    PubMed

    Shen, Han; Wang, Ying; Zhang, Zhiwei; Yang, Junjie; Hu, Shijun; Shen, Zhenya

    2015-01-01

    With the high mortality rate, coronary heart disease (CHD) has currently become a major life-threatening disease. The main pathological change of myocardial infarction (MI) is the induction of myocardial necrosis in infarction area which finally causes heart failure. Conventional treatments cannot regenerate the functional cell efficiently. Recent researches suggest that mesenchymal stem cells (MSCs) are able to differentiate into multiple lineages, including cardiomyocyte-like cells in vitro and in vivo, and they have been used for the treatment of MI to repair the injured myocardium and improve cardiac function. In this review, we will focus on the recent progress on MSCs derived cardiomyocytes for cardiac regeneration after MI.

  10. Transcription factor-induced activation of cardiac gene expression in human c-kit+ cardiac progenitor cells

    PubMed Central

    Vajravelu, Bathri N.; Moktar, Afsoon; Cao, Pengxiao; Moore, Joseph B.; Bolli, Roberto

    2017-01-01

    Although transplantation of c-kit+ cardiac progenitor cells (CPCs) significantly alleviates post-myocardial infarction left ventricular dysfunction, generation of cardiomyocytes by exogenous CPCs in the recipient heart has often been limited. Inducing robust differentiation would be necessary for improving the efficacy of the regenerative cardiac cell therapy. We assessed the hypothesis that differentiation of human c-kit+ CPCs can be enhanced by priming them with cardiac transcription factors (TFs). We introduced five different TFs (Gata4, MEF2C, NKX2.5, TBX5, and BAF60C) into CPCs, either alone or in combination, and then examined the expression of marker genes associated with the major cardiac cell types using quantitative RT-PCR. When introduced individually, Gata4 and TBX5 induced a subset of myocyte markers. Moreover, Gata4 alone significantly induced smooth muscle cell and fibroblast markers. Interestingly, these gene expression changes brought by Gata4 were also accompanied by morphological changes. In contrast, MEF2C and NKX2.5 were largely ineffective in initiating cardiac gene expression in CPCs. Surprisingly, introduction of multiple TFs in different combinations mostly failed to act synergistically. Likewise, addition of BAF60C to Gata4 and/or TBX5 did not further potentiate their effects on cardiac gene expression. Based on our results, it appears that GATA4 is able to potentiate gene expression programs associated with multiple cardiovascular lineages in CPCs, suggesting that GATA4 may be effective in priming CPCs for enhanced differentiation in the setting of stem cell therapy. PMID:28355297

  11. Transcription factor-induced activation of cardiac gene expression in human c-kit+ cardiac progenitor cells.

    PubMed

    Al-Maqtari, Tareq; Hong, Kyung U; Vajravelu, Bathri N; Moktar, Afsoon; Cao, Pengxiao; Moore, Joseph B; Bolli, Roberto

    2017-01-01

    Although transplantation of c-kit+ cardiac progenitor cells (CPCs) significantly alleviates post-myocardial infarction left ventricular dysfunction, generation of cardiomyocytes by exogenous CPCs in the recipient heart has often been limited. Inducing robust differentiation would be necessary for improving the efficacy of the regenerative cardiac cell therapy. We assessed the hypothesis that differentiation of human c-kit+ CPCs can be enhanced by priming them with cardiac transcription factors (TFs). We introduced five different TFs (Gata4, MEF2C, NKX2.5, TBX5, and BAF60C) into CPCs, either alone or in combination, and then examined the expression of marker genes associated with the major cardiac cell types using quantitative RT-PCR. When introduced individually, Gata4 and TBX5 induced a subset of myocyte markers. Moreover, Gata4 alone significantly induced smooth muscle cell and fibroblast markers. Interestingly, these gene expression changes brought by Gata4 were also accompanied by morphological changes. In contrast, MEF2C and NKX2.5 were largely ineffective in initiating cardiac gene expression in CPCs. Surprisingly, introduction of multiple TFs in different combinations mostly failed to act synergistically. Likewise, addition of BAF60C to Gata4 and/or TBX5 did not further potentiate their effects on cardiac gene expression. Based on our results, it appears that GATA4 is able to potentiate gene expression programs associated with multiple cardiovascular lineages in CPCs, suggesting that GATA4 may be effective in priming CPCs for enhanced differentiation in the setting of stem cell therapy.

  12. Slit and Robo control cardiac cell polarity and morphogenesis.

    PubMed

    Qian, Li; Liu, Jiandong; Bodmer, Rolf

    2005-12-20

    Basic aspects of heart morphogenesis involving migration, cell polarization, tissue alignment, and lumen formation may be conserved between Drosophila and humans, but little is known about the mechanisms that orchestrate the assembly of the heart tube in either organism. The extracellular-matrix molecule Slit and its Robo-family receptors are conserved regulators of axonal guidance. Here, we report a novel role of the Drosophila slit, robo, and robo2 genes in heart morphogenesis. Slit and Robo proteins specifically accumulate at the dorsal midline between the bilateral myocardial progenitors forming a linear tube. Manipulation of Slit localization or its overexpression causes disruption in heart tube alignment and assembly, and slit-deficient hearts show disruptions in cell-polarity marker localization within the myocardium. Similar phenotypes are observed when Robo and Robo2 are manipulated. Rescue experiments suggest that Slit is secreted from the myocardial progenitors and that Robo and Robo2 act in myocardial and pericardial cells, respectively. Genetic interactions suggest a cardiac morphogenesis network involving Slit/Robo, cell-polarity proteins, and other membrane-associated proteins. We conclude that Slit and Robo proteins contribute significantly to Drosophila heart morphogenesis by guiding heart cell alignment and adhesion and/or by inhibiting cell mixing between the bilateral compartments of heart cell progenitors and ensuring proper polarity of the myocardial epithelium.

  13. Mouse embryonic stem cell-derived cardiac myocytes in a cell culture dish.

    PubMed

    Glass, Carley; Singla, Reetu; Arora, Anshu; Singla, Dinender K

    2015-01-01

    Embryonic stem (ES) cells are pluripotent stem cells capable of self-renewal and have broad differentiation potential yielding cell types from all three germ layers. In the absence of differentiation inhibitory factors, when cultured in suspension, ES cells spontaneously differentiate and form three-dimensional cell aggregates termed embryoid bodies (EBs). Although various methods exist for the generation of EBs, the hanging drop method offers reproducibility and homogeneity from a predetermined number of ES cells. Herein, we describe the in vitro differentiation of mouse embryonic stem cells into cardiac myocytes using the hanging drop method and immunocytochemistry to identify cardiomyogenic differentiation. In brief, ES cells, placed in droplets on the lid of culture dishes following a 2-day incubation, yield embryoid bodies, which are resuspended and plated. 1-2 weeks following plating of the EBs, spontaneous beating areas can be observed and staining for specific cardiac markers can be achieved.

  14. Single-cell transcriptome and epigenomic reprogramming of cardiomyocyte-derived cardiac progenitor cells

    PubMed Central

    Chen, Xin; Chakravarty, Tushar; Zhang, Yiqiang; Li, Xiaojin; Zhong, Jiang F.; Wang, Charles

    2016-01-01

    The molecular basis underlying the dedifferentiation of mammalian adult cardiomyocytes (ACMs) into myocyte-derived cardiac progenitor cells (mCPCs) during cardiac tissue regeneration is poorly understood. We present data integrating single-cell transcriptome and whole-genome DNA methylome analyses of mouse mCPCs to understand the epigenomic reprogramming governing their intrinsic cellular plasticity. Compared to parental cardiomyocytes, mCPCs display epigenomic reprogramming with many differentially-methylated regions, both hypermethylated and hypomethylated, across the entire genome. Correlating well with the methylome, our single-cell transcriptomic data show that the genes encoding cardiac structure and function proteins are remarkably down-regulated in mCPCs, while those for cell cycle, proliferation, and stemness are significantly up-regulated. In addition, implanting mCPCs into infarcted mouse myocardium improves cardiac function with augmented left ventricular ejection fraction. This dataset suggests that the cellular plasticity of mammalian cardiomyocytes is the result of a well-orchestrated epigenomic reprogramming and a subsequent global transcriptomic alteration. Understanding cardiomyocyte epigenomic reprogramming may enable the design of future clinical therapies that induce cardiac regeneration, and prevent heart failure. PMID:27622691

  15. Electrophysiological effects of risperidone in mammalian cardiac cells.

    PubMed

    Magyar, János; Bányász, Tamás; Bagi, Zsolt; Pacher, Pál; Szentandrássy, Norbert; Fülöp, László; Kecskeméti, Valéria; Nánási, Péter P

    2002-10-01

    In this study, the effects of risperidone, the widely used antipsychotic drug, on isolated canine ventricular myocytes and guinea-pig papillary muscles were analyzed using conventional microelectrode and whole cell voltage-clamp techniques. Risperidone concentration-dependently lengthened action potential duration in guinea-pig papillary muscles (EC(50)=0.29+/-0.02 micro M) and single canine ventricular myocytes (EC(50)=0.48+/-0.14 micro M). This effect was reversible, showed reverse rate dependence, and it was most prominent on the terminal portion of repolarization. No significant effect of risperidone on the resting membrane potential, action potential amplitude or maximum rate of depolarization was observed. In voltage-clamped canine ventricular myocytes risperidone caused concentration-dependent block of the rapid component of the delayed rectifier K(+) current ( I(Kr)), measured as outward current tails at -40 mV, with an IC(50) of 0.92+/-0.26 micro M. Suppression of I(Kr) was not associated with changes in activation or deactivation kinetics. High concentration of risperidone (10 micro M) suppressed also the slow component of the delayed rectifier K(+) current ( I(Ks)) by 9.6+/-1.5% at +50 mV. These effects of risperidone developed rapidly and were readily reversible. Risperidone had no significant effect on the amplitude of other K(+) currents ( I(K1) and I(to)). The inhibition of cardiac I(Kr) current by risperidone may explain the cardiac side-effects observed occasionally with the drug. Our results suggest that risperidone displays class III antiarrhythmic properties, and as such, may produce QTc prolongation, especially in patients with long QT syndrome. Therefore, in psychotic patients having also cardiac disorders, ECG control may be suggested during risperidone therapy.

  16. Silk fibroin scaffolds enhance cell commitment of adult rat cardiac progenitor cells.

    PubMed

    Di Felice, Valentina; Serradifalco, Claudia; Rizzuto, Luigi; De Luca, Angela; Rappa, Francesca; Barone, Rosario; Di Marco, Patrizia; Cassata, Giovanni; Puleio, Roberto; Verin, Lucia; Motta, Antonella; Migliaresi, Claudio; Guercio, Annalisa; Zummo, Giovanni

    2015-11-01

    The use of three-dimensional (3D) cultures may induce cardiac progenitor cells to synthesize their own extracellular matrix (ECM) and sarcomeric proteins to initiate cardiac differentiation. 3D cultures grown on synthetic scaffolds may favour the implantation and survival of stem cells for cell therapy when pharmacological therapies are not efficient in curing cardiovascular diseases and when organ transplantation remains the only treatment able to rescue the patient's life. Silk fibroin-based scaffolds may be used to increase cell affinity to biomaterials and may be chemically modified to improve cell adhesion. In the present study, porous, partially orientated and electrospun nanometric nets were used. Cardiac progenitor cells isolated from adult rats were seeded by capillarity in the 3D structures and cultured inside inserts for 21 days. Under this condition, the cells expressed a high level of sarcomeric and cardiac proteins and synthesized a great quantity of ECM. In particular, partially orientated scaffolds induced the synthesis of titin, which is a fundamental protein in sarcomere assembly.

  17. CALCIUM-DRIVEN TRANSCRIPTION OF CARDIAC SPECIFYING GENE PROGRAM IN LIVER STEM CELLS

    EPA Science Inventory

    We have previously shown that a cloned liver stem cell line (WB F344) acquires a cardiac phenotype when seeded in a cardiac microenvironment in vivo and ex vivo. Here we investigated the mechanisms of this transdifferentiation in early (<72 hr) WB F344 cell, rat neonatal ventricu...

  18. Cellular cardiac electrophysiology modeling with Chaste and CellML.

    PubMed

    Cooper, Jonathan; Spiteri, Raymond J; Mirams, Gary R

    2014-01-01

    Chaste is an open-source C++ library for computational biology that has well-developed cardiac electrophysiology tissue simulation support. In this paper, we introduce the features available for performing cardiac electrophysiology action potential simulations using a wide range of models from the Physiome repository. The mathematics of the models are described in CellML, with units for all quantities. The primary idea is that the model is defined in one place (the CellML file), and all model code is auto-generated at compile or run time; it never has to be manually edited. We use ontological annotation to identify model variables describing certain biological quantities (membrane voltage, capacitance, etc.) to allow us to import any relevant CellML models into the Chaste framework in consistent units and to interact with them via consistent interfaces. This approach provides a great deal of flexibility for analysing different models of the same system. Chaste provides a wide choice of numerical methods for solving the ordinary differential equations that describe the models. Fixed-timestep explicit and implicit solvers are provided, as discussed in previous work. Here we introduce the Rush-Larsen and Generalized Rush-Larsen integration techniques, made available via symbolic manipulation of the model equations, which are automatically rearranged into the forms required by these approaches. We have also integrated the CVODE solvers, a 'gold standard' for stiff systems, and we have developed support for symbolic computation of the Jacobian matrix, yielding further increases in the performance and accuracy of CVODE. We discuss some of the technical details of this work and compare the performance of the available numerical methods. Finally, we discuss how this is generalized in our functional curation framework, which uses a domain-specific language for defining complex experiments as a basis for comparison of model behavior.

  19. Fibronectin biosynthesis and cell-surface expression by cardiac and non-cardiac endothelial cells.

    PubMed Central

    Johnson, C. M.; Helgeson, S. C.

    1993-01-01

    We examined the biosynthesis and surface expression of fibronectin, an adhesive glycoprotein, in several types of cultured porcine endothelial cells: pulmonary artery, thoracic aorta, coronary artery, aortic valve, and mitral valve. We used immunocytochemical staining to compare the levels of fibronectin present in these same tissues in vivo. Using endogenous radiolabeling, we found that all cell types except aortic valve endothelial cells synthesized and released into the culture media substantial quantities of fibronectin. Using radioiodination of intact cells, we found that, whereas both thoracic aorta and pulmonary artery cells had measurable fibronectin on the surface, aortic valve, mitral valve, and coronary artery cells had little cell-surface fibronectin present. Immunocytochemical staining showed that all endothelial regions except aortic valve had substantial quantities of immunoreactive fibronectin in vivo. These data suggest that the aortic valve endothelium may be distinct from other endothelia. Such differences could be important for the pathogenesis of valvular disease. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:8494044

  20. Use of Mesenchymal Stem Cells for Therapy of Cardiac Disease

    PubMed Central

    Karantalis, Vasileios; Hare, Joshua M.

    2015-01-01

    Despite substantial clinical advances over the past 65 years, cardiovascular disease remains the leading cause of death in America. The past 15 years has witnessed major basic and translational interest in the use of stem and/or precursor cells as a therapeutic agent for chronically injured organs. Among the cell types under investigation, adult mesenchymal stem cells (MSCs) are widely studied and in early stage clinical studies show promise for repair and regeneration of cardiac tissues. The ability of MSCs to differentiate into mesoderm and non-mesoderm derived tissues, their immunomodulatory effects, their availability and their key role in maintaining and replenishing endogenous stem cell niches have rendered them one of the most heavily investigated and clinically tested type of stem cell. Accumulating data from preclinical and early phase clinical trials document their safety when delivered as either autologous or allogeneic forms in a range of cardiovascular diseases, but also importantly define parameters of clinical efficacy that justify further investigation in larger clinical trials. Here, we review the biology of MSCs, their interaction with endogenous molecular and cellular pathways, and their modulation of immune responses. Additionally, we discuss factors that enhance their proliferative and regenerative ability and factors that may hinder their effectiveness in the clinical setting. PMID:25858066

  1. Induced pluripotent stem cell intervention rescues ventricular wall motion disparity, achieving biological cardiac resynchronization post-infarction

    PubMed Central

    Yamada, Satsuki; Nelson, Timothy J; Kane, Garvan C; Martinez-Fernandez, Almudena; Crespo-Diaz, Ruben J; Ikeda, Yasuhiro; Perez-Terzic, Carmen; Terzic, Andre

    2013-01-01

    Dyssynchronous myocardial motion aggravates cardiac pump function. Cardiac resynchronization using pacing devices is a standard-of-care in the management of heart failure. Post-infarction, however, scar tissue formation impedes the efficacy of device-based therapy. The present study tests a regenerative approach aimed at targeting the origin of abnormal motion to prevent dyssynchronous organ failure. Induced pluripotent stem (iPS) cells harbour a reparative potential, and were here bioengineered from somatic fibroblasts reprogrammed with the stemness factors OCT3/4, SOX2, KLF4, and c-MYC. In a murine infarction model, within 30 min of coronary ligation, iPS cells were delivered to mapped infarcted areas. Focal deformation and dysfunction underlying progressive heart failure was resolved prospectively using speckle-tracking imaging. Tracked at high temporal and spatial resolution, regional iPS cell transplantation restored, within 10 days post-infarction, the contractility of targeted infarcted foci and nullified conduction delay in adjacent non-infarcted regions. Local iPS cell therapy, but not delivery of parental fibroblasts or vehicle, prevented or normalized abnormal strain patterns correcting the decrease in peak strain, disparity of time-to-peak strain, and pathological systolic stretch. Focal benefit of iPS cell intervention translated into improved left ventricular conduction and contractility, reduced scar, and reversal of structural remodelling, protecting from organ decompensation. Thus, in ischaemic cardiomyopathy, targeted iPS cell transplantation synchronized failing ventricles, offering a regenerative strategy to achieve biological resynchronization. PMID:23568891

  2. Recreating the Cardiac Microenvironment in Pluripotent Stem Cell Models of Human Physiology and Disease.

    PubMed

    Atmanli, Ayhan; Domian, Ibrahim John

    2016-12-19

    The advent of human pluripotent stem cell (hPSC) biology has opened unprecedented opportunities for the use of tissue engineering to generate human cardiac tissue for in vitro study. Engineering cardiac constructs that recapitulate human development and disease requires faithful recreation of the cardiac niche in vitro. Here we discuss recent progress in translating the in vivo cardiac microenvironment into PSC models of the human heart. We review three key physiologic features required to recreate the cardiac niche and facilitate normal cardiac differentiation and maturation: the biochemical, biophysical, and bioelectrical signaling cues. Finally, we discuss key barriers that must be overcome to fulfill the promise of stem cell biology in preclinical applications and ultimately in clinical practice.

  3. HMGB1-stimulated human primary cardiac fibroblasts exert a paracrine action on human and murine cardiac stem cells.

    PubMed

    Rossini, Alessandra; Zacheo, Antonella; Mocini, David; Totta, Pierangela; Facchiano, Antonio; Castoldi, Raffaella; Sordini, Paolo; Pompilio, Giulio; Abeni, Damiano; Capogrossi, Maurizio C; Germani, Antonia

    2008-04-01

    High Mobility Box 1 Protein (HMGB1) is a cytokine released into the extracellular space by necrotic cells and activated macrophages in response to injury. We recently demonstrated that HMGB1 administration into the mouse heart during acute myocardial infarction induces cardiac tissue regeneration by activating resident cardiac c-kit+ cells (CSCs) and significantly enhances left ventricular function. In the present study it was analyzed the hypothesis that human cardiac fibroblasts (cFbs) exposed to HMGB1 may exert a paracrine effect on mouse and human CSCs. Human cFbs expressed the HMGB1 receptor RAGE. Luminex technology and ELISA assays revealed that HMGB1 significantly enhanced VEGF, PlGF, Mip-1alpha, IFN-gamma, GM-CSF, Il-10, Il-1beta, Il-4, Il-1ra, Il-9 and TNF-alpha in cFbs cell culture medium. HMGB1-stimulated cFbs conditioned media induced CSC migration and proliferation. These effects were significantly higher to those obtained when HMGB1 was added directly to the culture medium. In conclusion, we provide evidence that HMGB1 may act in a paracrine manner stimulating growth factor, cytokine and chemokine release by cFbs which, in turn, modulate CSC function. Via this mechanism HMGB1 may contribute to cardiac tissue regeneration.

  4. HL-1 cells: a cardiac muscle cell line that contracts and retains phenotypic characteristics of the adult cardiomyocyte.

    PubMed

    Claycomb, W C; Lanson, N A; Stallworth, B S; Egeland, D B; Delcarpio, J B; Bahinski, A; Izzo, N J

    1998-03-17

    We have derived a cardiac muscle cell line, designated HL-1, from the AT-1 mouse atrial cardiomyocyte tumor lineage. HL-1 cells can be serially passaged, yet they maintain the ability to contract and retain differentiated cardiac morphological, biochemical, and electrophysiological properties. Ultrastructural characteristics typical of embryonic atrial cardiac muscle cells were found consistently in the cultured HL-1 cells. Reverse transcriptase-PCR-based analyses confirmed a pattern of gene expression similar to that of adult atrial myocytes, including expression of alpha-cardiac myosin heavy chain, alpha-cardiac actin, and connexin43. They also express the gene for atrial natriuretic factor. Immunohistochemical staining of the HL-1 cells indicated that the distribution of the cardiac-specific markers desmin, sarcomeric myosin, and atrial natriuretic factor was similar to that of cultured atrial cardiomyocytes. A delayed rectifier potassium current (IKr) was the most prominent outward current in HL-1 cells. The activating currents displayed inward rectification and deactivating current tails were voltage-dependent, saturated at >+20 mV, and were highly sensitive to dofetilide (IC50 of 46.9 nM). Specific binding of [3H]dofetilide was saturable and fit a one-site binding isotherm with a Kd of 140 +/- 60 nM and a Bmax of 118 fmol per 10(5) cells. HL-1 cells represent a cardiac myocyte cell line that can be repeatedly passaged and yet maintain a cardiac-specific phenotype.

  5. Spontaneous Calcium Oscillations Regulate Human Cardiac Progenitor Cell Growth

    PubMed Central

    Ferreira-Martins, João; Rondon-Clavo, Carlos; Tugal, Derin; Korn, Justin A; Rizzi, Roberto; Padin-Iruegas, Maria Elena; Ottolenghi, Sergio; De Angelis, Antonella; Urbanek, Konrad; Iwata, Noriko; D’Amario, Domenico; Hosoda, Toru; Leri, Annarosa; Kajstura, Jan; Anversa, Piero; Rota, Marcello

    2009-01-01

    Rationale The adult heart possesses a pool of progenitor cells stored in myocardial niches but the mechanisms involved in the activation of this cell compartment are currently unknown. Objective Ca2+ promotes cell growth raising the possibility that changes in intracellular Ca2+ initiate division of c-kit-positive human cardiac progenitor cells (hCPCs) and determine their fate. Methods and Results Ca2+ oscillations were identified in hCPCs and these events occurred independently from coupling with cardiomyocytes or the presence of extracellular Ca2+. These findings were confirmed in the heart of transgenic mice in which EGFP was under the control of the c-kit-promoter. Ca2+ oscillations in hCPCs were regulated by the release of Ca2+ from the ER through activation of inositol 1,4,5-triphosphate receptors (IP3Rs) and the re-uptake of Ca2+ by the sarco/endoplasmic reticulum Ca2+ pump (SERCA). IP3Rs and SERCA were highly expressed in hCPCs while ryanodine receptors were not detected. Although Na+-Ca2+ exchanger, store-operated Ca2+-channels and plasma membrane Ca2+-pump were present and functional in hCPCs, they had no direct effects on Ca2+ oscillations. Conversely, Ca2+ oscillations and their frequency markedly increased with ATP and histamine which activated purinoceptors and histamine-1 receptors highly expressed in hCPCs. Importantly, Ca2+ oscillations in hCPCs were coupled with the entry of cells into the cell cycle and BrdUrd incorporation. Induction of Ca2+ oscillations in hCPCs prior to their intramyocardial delivery to infarcted hearts was associated with enhanced engraftment and expansion of these cells promoting the generation of a large myocyte progeny. Conclusion IP3R-mediated Ca2+ mobilization control hCPC growth and their regenerative potential. PMID:19745162

  6. Second heart field cardiac progenitor cells in the early mouse embryo.

    PubMed

    Francou, Alexandre; Saint-Michel, Edouard; Mesbah, Karim; Théveniau-Ruissy, Magali; Rana, M Sameer; Christoffels, Vincent M; Kelly, Robert G

    2013-04-01

    At the end of the first week of mouse gestation, cardiomyocyte differentiation initiates in the cardiac crescent to give rise to the linear heart tube. The heart tube subsequently elongates by addition of cardiac progenitor cells from adjacent pharyngeal mesoderm to the growing arterial and venous poles. These progenitor cells, termed the second heart field, originate in splanchnic mesoderm medial to cells of the cardiac crescent and are patterned into anterior and posterior domains adjacent to the arterial and venous poles of the heart, respectively. Perturbation of second heart field cell deployment results in a spectrum of congenital heart anomalies including conotruncal and atrial septal defects seen in human patients. Here, we briefly review current knowledge of how the properties of second heart field cells are controlled by a network of transcriptional regulators and intercellular signaling pathways. Focus will be on 1) the regulation of cardiac progenitor cell proliferation in pharyngeal mesoderm, 2) the control of progressive progenitor cell differentiation and 3) the patterning of cardiac progenitor cells in the dorsal pericardial wall. Coordination of these three processes in the early embryo drives progressive heart tube elongation during cardiac morphogenesis. This article is part of a Special Issue entitled: Cardiomyocyte Biology: Cardiac Pathways of Differentiation, Metabolism and Contraction.

  7. Analysis of electric field stimulation of single cardiac muscle cells.

    PubMed Central

    Tung, L; Borderies, J R

    1992-01-01

    Electrical stimulation of cardiac cells by imposed extracellular electric fields results in a transmembrane potential which is highly nonuniform, with one end of the cell depolarized and the other end hyperpolarized along the field direction. To date, the implications of the close proximity of oppositely polarized membranes on excitability have not been explored. In this work we compare the biophysical basis for field stimulation of cells at rest with that for intracellular current injection, using three Luo-Rudy type membrane patches coupled together as a lumped model to represent the cell membrane. Our model shows that cell excitation is a function of the temporal and spatial distribution of ionic currents and transmembrane potential. The extracellular and intracellular forms of stimulation were compared in greater detail for monophasic and symmetric biphasic rectangular pulses, with duration ranging from 0.5 to 10 ms. Strength-duration curves derived for field stimulation show that over a wide range of pulse durations, biphasic waveforms can recruit and activate membrane patches about as effectively as can monophasic waveforms having the same total pulse duration. We find that excitation with biphasic stimulation results from a synergistic, temporal summation of inward currents through the sodium channel in membrane patches at opposite ends of the cell. Furthermore, with both waveform types, a net inward current through the inwardly rectifying potassium channel contributes to initial membrane depolarization. In contrast, models of stimulation by intracellular current injection do not account for the nonuniformity of transmembrane potential and produce substantially different (even contradictory) results for the case of stimulation from rest. PMID:1420884

  8. Overexpression of TIMP-1 in embryonic stem cells attenuates adverse cardiac remodeling following myocardial infarction.

    PubMed

    Glass, Carley; Singla, Dinender K

    2012-01-01

    Transplanted embryonic stem (ES) cells, following myocardial infarction (MI), contribute to limited cardiac repair and regeneration with improved function. Therefore, novel strategies are still needed to understand the effects of genetically modified transplanted stem cells on cardiac remodeling. The present study evaluates whether transplanted mouse ES cells overexpressing TIMP-1, an antiapoptotic and antifibrotic protein, can enhance cardiac myocyte differentiation, inhibit native cardiac myocyte apoptosis, reduce fibrosis, and improve cardiac function in the infarcted myocardium. MI was produced in C57BL/6 mice by coronary artery ligation. TIMP-1-ES cells, ES cells, or culture medium (control) were transplanted into the peri-infarct region of the heart. Immunofluorescence, TUNEL staining, caspase-3 activity, ELISAs, histology, and echocardiography were used to identify newly differentiated cardiac myocytes and assess apoptosis, fibrosis, and heart function. Two weeks post-MI, significantly (p < 0.05) enhanced engraftment and cardiac myocyte differentiation was observed in TIMP-1-ES cell-transplanted hearts compared with hearts transplanted with ES cells and control. Hearts transplanted with TIMP-1-ES cells demonstrated a reduction in apoptosis as well as an increase (p< 0.05) in p-Akt activity compared with ES cells or culture media controls. Infarct size and interstitial and vascular fibrosis were significantly (p< 0.05) decreased in the TIMP-1-ES cell group compared to controls. Furthermore, MMP-9, a key profibrotic protein, was significantly (p < 0.01) reduced following TIMP-1-ES cell transplantation. Echocardiography data showed fractional shortening and ejection fraction were significantly (p< 0.05) improved in the TIMP-1-ES cell group compared with respective controls. Our data suggest that transplanted ES cells overexpressing TIMP-1 attenuate adverse myocardial remodeling and improve cardiac function compared with ES cells that may have therapeutic

  9. Chronic infusion of enalaprilat into hypothalamic paraventricular nucleus attenuates angiotensin II-induced hypertension and cardiac hypertrophy by restoring neurotransmitters and cytokines

    SciTech Connect

    Kang, Yu-Ming; Zhang, Dong-Mei; Yu, Xiao-Jing; Yang, Qing; Qi, Jie; Su, Qing; Suo, Yu-Ping; Yue, Li-Ying; Zhu, Guo-Qing; Qin, Da-Nian

    2014-02-01

    The renin–angiotensin system (RAS) in the brain is involved in the pathogenesis of hypertension. We hypothesized that inhibition of angiotensin-converting enzyme (ACE) in the hypothalamic paraventricular nucleus (PVN) attenuates angiotensin II (ANG II)-induced hypertension via restoring neurotransmitters and cytokines. Rats underwent subcutaneous infusions of ANG II or saline and bilateral PVN infusions of ACE inhibitor enalaprilat (ENL, 2.5 μg/h) or vehicle for 4 weeks. ANG II infusion resulted in higher mean arterial pressure and cardiac hypertrophy as indicated by increased whole heart weight/body weight ratio, whole heart weight/tibia length ratio, left ventricular weight/tibia length ratio, and mRNA expressions of cardiac atrial natriuretic peptide and beta-myosin heavy chain. These ANG II-infused rats had higher PVN levels of glutamate, norepinephrine, tyrosine hydroxylase, pro-inflammatory cytokines (PICs) and the chemokine monocyte chemoattractant protein-1, and lower PVN levels of gamma-aminobutyric acid, interleukin (IL)-10 and the 67-kDa isoform of glutamate decarboxylase (GAD67), and higher plasma levels of PICs, norepinephrine and aldosterone, and lower plasma IL-10, and higher renal sympathetic nerve activity. However, PVN treatment with ENL attenuated these changes. PVN microinjection of ANG II induced increases in IL-1β and IL-6, and a decrease in IL-10 in the PVN, and pretreatment with angiotensin II type 1 receptor (AT1-R) antagonist losartan attenuated these changes. These findings suggest that ANG II infusion induces an imbalance between excitatory and inhibitory neurotransmitters and an imbalance between pro- and anti-inflammatory cytokines in the PVN, and PVN inhibition of the RAS restores neurotransmitters and cytokines in the PVN, thereby attenuating ANG II-induced hypertension and cardiac hypertrophy. - Highlights: • Chronic ANG II infusion results in sympathetic hyperactivity and cardiac hypertrophy. • PVN inhibition of ACE

  10. Embryonic stem cells improve cardiac function in Doxorubicin-induced cardiomyopathy mediated through multiple mechanisms.

    PubMed

    Singla, Dinender K; Ahmed, Aisha; Singla, Reetu; Yan, Binbin

    2012-01-01

    Doxorubicin (DOX) is an effective antineoplastic agent used for the treatment of a variety of cancers. Unfortunately, its use is limited as this drug induces cardiotoxicity and heart failure as a side effect. There is no report that describes whether transplanted embryonic stem (ES) cells or their conditioned medium (CM) in DOX-induced cardiomyopathy (DIC) can repair and regenerate myocardium. Therefore, we transplanted ES cells or CM in DIC to examine apoptosis, fibrosis, cytoplasmic vacuolization, and myofibrillar loss and their associated Akt and ERK pathway. Moreover, we also determined activation of endogenous c-kit(+ve) cardiac stem cells (CSCs), levels of HGF and IGF-1, growth factors required for c-kit cell activation, and their differentiation into cardiac myocytes, which also contributes in cardiac regeneration and improved heart function. We generated DIC in C57Bl/6 mice (cumulative dose of DOX 12 mg/kg body weight, IP), and animals were treated with ES cells, CM, or cell culture medium in controls. Two weeks post-DIC, ES cells or CM transplanted hearts showed a significant (p < 0.05) decrease in cardiac apoptotic nuclei and their regulation with Akt and ERK pathway. Cardiac fibrosis observed in the ES cell or CM groups was significantly less compared with DOX and cell culture medium groups (p < 0.05). Next, cytoplasmic vacuolization and myofibrillar loss was reduced (p < 0.05) following treatment with ES cells or CM. Moreover, our data also demonstrated increased levels of c-kit(+ve) CSCs in ES cells or CM hearts and differentiated cardiac myocytes from these CSCs, suggesting endogenous cardiac regeneration. Importantly, the levels of HFG and IGF-1 were significantly increased in ES cells or CM transplanted hearts. In conclusion, we reported that transplanted ES cells or CM in DIC hearts significantly decreases various adverse pathological mechanisms as well as enhances cardiac regeneration that effectively contributes to improved heart function.

  11. Tubular Cardiac Tissues Derived from Human Induced Pluripotent Stem Cells Generate Pulse Pressure In Vivo

    PubMed Central

    Seta, Hiroyoshi; Matsuura, Katsuhisa; Sekine, Hidekazu; Yamazaki, Kenji; Shimizu, Tatsuya

    2017-01-01

    Human induced pluripotent stem (iPS) cell-derived cardiac cells provide the possibility to fabricate cardiac tissues for transplantation. However, it remains unclear human bioengineered cardiac tissues function as a functional pump in vivo. Human iPS cells induced to cardiomyocytes in suspension were cultured on temperature-responsive dishes to fabricate cardiac cell sheets. Two pairs of triple-layered sheets were transplanted to wrap around the inferior vena cava (IVC) of nude rats. At 4 weeks after transplantation, inner pressure changes in the IVC were synchronized with electrical activations of the graft. Under 80 pulses per minute electrical stimulation, the inner pressure changes at 8 weeks increased to 9.1 ± 3.2 mmHg, which were accompanied by increases in the baseline inner pressure of the IVC. Immunohistochemical analysis revealed that 0.5-mm-thick cardiac troponin T-positive cardiac tissues, which contained abundant human mitochondria, were clearly engrafted lamellar around the IVC and surrounded by von Willebrand factor-positive capillary vessels. The mRNA expression of several contractile proteins in cardiac tissues at 8 weeks in vivo was significantly upregulated compared with those at 4 weeks. We succeeded in generating pulse pressure by tubular human cardiac tissues in vivo. This technology might lead to the development of a bioengineered heart assist pump. PMID:28358136

  12. Cardiac fibroblast-derived extracellular matrix (biomatrix) as a model for the studies of cardiac primitive cell biological properties in normal and pathological adult human heart.

    PubMed

    Castaldo, Clotilde; Di Meglio, Franca; Miraglia, Rita; Sacco, Anna Maria; Romano, Veronica; Bancone, Ciro; Della Corte, Alessandro; Montagnani, Stefania; Nurzynska, Daria

    2013-01-01

    Cardiac tissue regeneration is guided by stem cells and their microenvironment. It has been recently described that both cardiac stem/primitive cells and extracellular matrix (ECM) change in pathological conditions. This study describes the method for the production of ECM typical of adult human heart in the normal and pathological conditions (ischemic heart disease) and highlights the potential use of cardiac fibroblast-derived ECM for in vitro studies of the interactions between ECM components and cardiac primitive cells responsible for tissue regeneration. Fibroblasts isolated from adult human normal and pathological heart with ischemic cardiomyopathy were cultured to obtain extracellular matrix (biomatrix), composed of typical extracellular matrix proteins, such as collagen and fibronectin, and matricellular proteins, laminin, and tenascin. After decellularization, this substrate was used to assess biological properties of cardiac primitive cells: proliferation and migration were stimulated by biomatrix from normal heart, while both types of biomatrix protected cardiac primitive cells from apoptosis. Our model can be used for studies of cell-matrix interactions and help to determine the biochemical cues that regulate cardiac primitive cell biological properties and guide cardiac tissue regeneration.

  13. Machine learning classification of cell-specific cardiac enhancers uncovers developmental subnetworks regulating progenitor cell division and cell fate specification.

    PubMed

    Ahmad, Shaad M; Busser, Brian W; Huang, Di; Cozart, Elizabeth J; Michaud, Sébastien; Zhu, Xianmin; Jeffries, Neal; Aboukhalil, Anton; Bulyk, Martha L; Ovcharenko, Ivan; Michelson, Alan M

    2014-02-01

    The Drosophila heart is composed of two distinct cell types, the contractile cardial cells (CCs) and the surrounding non-muscle pericardial cells (PCs), development of which is regulated by a network of conserved signaling molecules and transcription factors (TFs). Here, we used machine learning with array-based chromatin immunoprecipitation (ChIP) data and TF sequence motifs to computationally classify cell type-specific cardiac enhancers. Extensive testing of predicted enhancers at single-cell resolution revealed the added value of ChIP data for modeling cell type-specific activities. Furthermore, clustering the top-scoring classifier sequence features identified novel cardiac and cell type-specific regulatory motifs. For example, we found that the Myb motif learned by the classifier is crucial for CC activity, and the Myb TF acts in concert with two forkhead domain TFs and Polo kinase to regulate cardiac progenitor cell divisions. In addition, differential motif enrichment and cis-trans genetic studies revealed that the Notch signaling pathway TF Suppressor of Hairless [Su(H)] discriminates PC from CC enhancer activities. Collectively, these studies elucidate molecular pathways used in the regulatory decisions for proliferation and differentiation of cardiac progenitor cells, implicate Su(H) in regulating cell fate decisions of these progenitors, and document the utility of enhancer modeling in uncovering developmental regulatory subnetworks.

  14. Machine learning classification of cell-specific cardiac enhancers uncovers developmental subnetworks regulating progenitor cell division and cell fate specification

    PubMed Central

    Ahmad, Shaad M.; Busser, Brian W.; Huang, Di; Cozart, Elizabeth J.; Michaud, Sébastien; Zhu, Xianmin; Jeffries, Neal; Aboukhalil, Anton; Bulyk, Martha L.; Ovcharenko, Ivan; Michelson, Alan M.

    2014-01-01

    The Drosophila heart is composed of two distinct cell types, the contractile cardial cells (CCs) and the surrounding non-muscle pericardial cells (PCs), development of which is regulated by a network of conserved signaling molecules and transcription factors (TFs). Here, we used machine learning with array-based chromatin immunoprecipitation (ChIP) data and TF sequence motifs to computationally classify cell type-specific cardiac enhancers. Extensive testing of predicted enhancers at single-cell resolution revealed the added value of ChIP data for modeling cell type-specific activities. Furthermore, clustering the top-scoring classifier sequence features identified novel cardiac and cell type-specific regulatory motifs. For example, we found that the Myb motif learned by the classifier is crucial for CC activity, and the Myb TF acts in concert with two forkhead domain TFs and Polo kinase to regulate cardiac progenitor cell divisions. In addition, differential motif enrichment and cis-trans genetic studies revealed that the Notch signaling pathway TF Suppressor of Hairless [Su(H)] discriminates PC from CC enhancer activities. Collectively, these studies elucidate molecular pathways used in the regulatory decisions for proliferation and differentiation of cardiac progenitor cells, implicate Su(H) in regulating cell fate decisions of these progenitors, and document the utility of enhancer modeling in uncovering developmental regulatory subnetworks. PMID:24496624

  15. Electrotonic loading of anisotropic cardiac monolayers by unexcitable cells depends on connexin type and expression level

    PubMed Central

    McSpadden, Luke C.; Kirkton, Robert D.; Bursac, Nenad

    2009-01-01

    Understanding how electrotonic loading of cardiomyocytes by unexcitable cells alters cardiac impulse conduction may be highly relevant to fibrotic heart disease. In this study, we optically mapped electrical propagation in confluent, aligned neonatal rat cardiac monolayers electrotonically loaded with cardiac fibroblasts, control human embryonic kidney (HEK-293) cells, or HEK-293 cells genetically engineered to overexpress the gap junction proteins connexin-43 or connexin-45. Gap junction expression and function were assessed by immunostaining, immunoblotting, and fluorescence recovery after photobleaching and were correlated with the optically mapped propagation of action potentials. We found that neonatal rat ventricular fibroblasts negative for the myofibroblast marker smooth muscle α-actin expressed connexin-45 rather than connexin-43 or connexin-40, weakly coupled to cardiomyocytes, and, without significant depolarization of cardiac resting potential, slowed cardiac conduction to 75% of control only at high (>60%) coverage densities, similar to loading effects found from HEK-293 cells expressing similar levels of connexin-45. In contrast, HEK-293 cells with connexin-43 expression similar to that of cardiomyocytes significantly decreased cardiac conduction velocity and maximum capture rate to as low as 22% and 25% of control values, respectively, while increasing cardiac action potential duration to 212% of control and cardiac resting potential from −71.6 ± 4.9 mV in controls to −65.0 ± 3.8 mV. For all unexcitable cell types and coverage densities, velocity anisotropy ratio remained unchanged. Despite the induced conduction slowing, none of the loading cell types increased the proportion of spontaneously active monolayers. These results signify connexin isoform and expression level as important contributors to potential electrical interactions between unexcitable cells and myocytes in cardiac tissue. PMID:19494239

  16. Constitutive properties of adult mammalian cardiac muscle cells

    NASA Technical Reports Server (NTRS)

    Zile, M. R.; Richardson, K.; Cowles, M. K.; Buckley, J. M.; Koide, M.; Cowles, B. A.; Gharpuray, V.; Cooper, G. 4th

    1998-01-01

    BACKGROUND: The purpose of this study was to determine whether changes in the constitutive properties of the cardiac muscle cell play a causative role in the development of diastolic dysfunction. METHODS AND RESULTS: Cardiocytes from normal and pressure-hypertrophied cats were embedded in an agarose gel, placed on a stretching device, and subjected to a change in stress (sigma), and resultant changes in cell strain (epsilon) were measured. These measurements were used to examine the passive elastic spring, viscous damping, and myofilament activation. The passive elastic spring was assessed in protocol A by increasing the sigma on the agarose gel at a constant rate to define the cardiocyte sigma-versus-epsilon relationship. Viscous damping was assessed in protocol B from the loop area between the cardiocyte sigma-versus-epsilon relationship during an increase and then a decrease in sigma. In both protocols, myofilament activation was minimized by a reduction in [Ca2+]i. Myofilament activation effects were assessed in protocol C by defining cardiocyte sigma versus epsilon during an increase in sigma with physiological [Ca2+]i. In protocol A, the cardiocyte sigma-versus-epsilon relationship was similar in normal and hypertrophied cells. In protocol B, the loop area was greater in hypertrophied than normal cardiocytes. In protocol C, the sigma-versus-epsilon relation in hypertrophied cardiocytes was shifted to the left compared with normal cells. CONCLUSIONS: Changes in viscous damping and myofilament activation in combination may cause pressure-hypertrophied cardiocytes to resist changes in shape during diastole and contribute to diastolic dysfunction.

  17. Potential effects of intrinsic heart pacemaker cell mechanisms on dysrhythmic cardiac action potential firing

    PubMed Central

    Yaniv, Yael; Tsutsui, Kenta; Lakatta, Edward G.

    2015-01-01

    The heart's regular electrical activity is initiated by specialized cardiac pacemaker cells residing in the sinoatrial node. The rate and rhythm of spontaneous action potential firing of sinoatrial node cells are regulated by stochastic mechanisms that determine the level of coupling of chemical to electrical clocks within cardiac pacemaker cells. This coupled-clock system is modulated by autonomic signaling from the brain via neurotransmitter release from the vagus and sympathetic nerves. Abnormalities in brain-heart clock connections or in any molecular clock activity within pacemaker cells lead to abnormalities in the beating rate and rhythm of the pacemaker tissue that initiates the cardiac impulse. Dysfunction of pacemaker tissue can lead to tachy-brady heart rate alternation or exit block that leads to long atrial pauses and increases susceptibility to other cardiac arrhythmia. Here we review evidence for the idea that disturbances in the intrinsic components of pacemaker cells may be implemented in arrhythmia induction in the heart. PMID:25755643

  18. Restoration of WNT4 inhibits cell growth in leukemia-derived cell lines

    PubMed Central

    2013-01-01

    Background WNT signaling pathways are significantly altered during cancer development. Vertebrates possess two classes of WNT signaling pathways: the “canonical” WNT/β-catenin signaling pathway, and the “non-canonical” pathways including WNT/Ca2+ and WNT/Planar cell polarity [PCP] signaling. WNT4 influences hematopoietic progenitor cell expansion and survival; however, WNT4 function in cancer development and the resulting implications for oncogenesis are poorly understood. The aim of this study was twofold: first, to determine the expression of WNT4 in mature peripheral blood cells and diverse leukemia-derived cells including cell lines from hematopoietic neoplasms and cells from patients with leukemia; second, to identify the effect of this ligand on the proliferation and apoptosis of the blast-derived cell lines BJAB, Jurkat, CEM, K562, and HL60. Methods We determined WNT4 expression by quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) in peripheral blood mononuclear cells (PBMCs) and T- and B-lymphocytes from healthy individuals, as well as from five leukemia-derived cell lines and blasts derived from patients with leukemia. To analyze the effect of WNT4 on cell proliferation, PBMCs and cell lines were exposed to a commercially available WNT4 recombinant human protein. Furthermore, WNT4 expression was restored in BJAB cells using an inducible lentiviral expression system. Cell viability and proliferation were measured by the addition of WST-1 to cell cultures and counting cells; in addition, the progression of the cell cycle and the amount of apoptosis were analyzed in the absence or presence of WNT4. Finally, the expression of WNT-pathway target genes was measured by qRT-PCR. Results WNT4 expression was severely reduced in leukemia-derived cell lines and blasts derived from patients with leukemia. The exposure of cell lines to WNT4 recombinant protein significantly inhibited cell proliferation; inducing WNT4 expression in BJAB

  19. Cardiomyocytes from phorbol myristate acetate-activated mesenchymal stem cells restore electromechanical function in infarcted rat hearts

    PubMed Central

    Song, Heesang; Hwang, Hye Jin; Chang, Woochul; Song, Byeong-Wook; Cha, Min-Ji; Lim, Soyeon; Choi, Eun Ju; Ham, Onju; Lee, Chang Youn; Park, Jun-Hee; Lee, Se-Yeon; Choi, Eunmi; Lee, Chungkeun; Lee, Myoungho; Lee, Moon-Hyoung; Kim, Sung-Hou; Jang, Yangsoo; Hwang, Ki-Chul

    2011-01-01

    Despite the safety and feasibility of mesenchymal stem cell (MSC) therapy, an optimal cell type has not yet emerged in terms of electromechanical integration in infarcted myocardium. We found that poor to moderate survival benefits of MSC-implanted rats were caused by incomplete electromechanical integration induced by tissue heterogeneity between myocytes and engrafted MSCs in the infarcted myocardium. Here, we report the development of cardiogenic cells from rat MSCs activated by phorbol myristate acetate, a PKC activator, that exhibited high expressions of cardiac-specific markers and Ca2+ homeostasis-related proteins and showed adrenergic receptor signaling by norepinephrine. Histological analysis showed high connexin 43 coupling, few inflammatory cells, and low fibrotic markers in myocardium implanted with these phorbol myristate acetate-activated MSCs. Infarct hearts implanted with these cells exhibited restoration of conduction velocity through decreased tissue heterogeneity and improved myocardial contractility. These findings have major implications for the development of better cell types for electromechanical integration of cell-based treatment for infarcted myocardium. PMID:21173226

  20. Adult stem cells for cardiac repair: a choice between skeletal myoblasts and bone marrow stem cells.

    PubMed

    Ye, Lei; Haider, Husnain Kh; Sim, Eugene K W

    2006-01-01

    The real promise of a stem cell-based approach for cardiac regeneration and repair lies in the promotion of myogenesis and angiogenesis at the site of the cell graft to achieve both structural and functional benefits. Despite all of the progress and promise in this field, many unanswered questions remain; the answers to these questions will provide the much-needed breakthrough to harness the real benefits of cell therapy for the heart in the clinical perspective. One of the major issues is the choice of donor cell type for transplantation. Multiple cell types with varying potentials have been assessed for their ability to repopulate the infarcted myocardium; however, only the adult stem cells, that is, skeletal myoblasts (SkM) and bone marrow-derived stem cells (BMC), have been translated from the laboratory bench to clinical use. Which of these two cell types will provide the best option for clinical application in heart cell therapy remains arguable. With results pouring in from the long-term follow-ups of previously conducted phase I clinical studies, and with the onset of phase II clinical trials involving larger population of patients, transplantation of stem cells as a sole therapy without an adjunct conventional revascularization procedure will provide a deeper insight into the effectiveness of this approach. The present article discusses the pros and cons of using SkM and BMC individually or in combination for cardiac repair, and critically analyzes the progress made with each cell type.

  1. Three-dimensional cardiac microtissues composed of cardiomyocytes and endothelial cells co-differentiated from human pluripotent stem cells

    PubMed Central

    van Meer, Berend J.; Tertoolen, Leon G. J.

    2017-01-01

    ABSTRACT Cardiomyocytes and endothelial cells in the heart are in close proximity and in constant dialogue. Endothelium regulates the size of the heart, supplies oxygen to the myocardium and secretes factors that support cardiomyocyte function. Robust and predictive cardiac disease models that faithfully recapitulate native human physiology in vitro would therefore ideally incorporate this cardiomyocyte-endothelium crosstalk. Here, we have generated and characterized human cardiac microtissues in vitro that integrate both cell types in complex 3D structures. We established conditions for simultaneous differentiation of cardiomyocytes and endothelial cells from human pluripotent stem cells following initial cardiac mesoderm induction. The endothelial cells expressed cardiac markers that were also present in primary cardiac microvasculature, suggesting cardiac endothelium identity. These cell populations were further enriched based on surface markers expression, then recombined allowing development of beating 3D structures termed cardiac microtissues. This in vitro model was robustly reproducible in both embryonic and induced pluripotent stem cells. It thus represents an advanced human stem cell-based platform for cardiovascular disease modelling and testing of relevant drugs. PMID:28279973

  2. Exon Skipping and Gene Transfer Restore Dystrophin Expression in Human Induced Pluripotent Stem Cells-Cardiomyocytes Harboring DMD Mutations

    PubMed Central

    Dick, Emily; Kalra, Spandan; Anderson, David; George, Vinoj; Ritso, Morten; Laval, Steven H.; Barresi, Rita; Aartsma-Rus, Annemieke; Lochmüller, Hanns

    2013-01-01

    With an incidence of ∼1:3,500 to 5,000 in male children, Duchenne muscular dystrophy (DMD) is an X-linked disorder in which progressive muscle degeneration occurs and affected boys usually die in their twenties or thirties. Cardiac involvement occurs in 90% of patients and heart failure accounts for up to 40% of deaths. To enable new therapeutics such as gene therapy and exon skipping to be tested in human cardiomyocytes, we produced human induced pluripotent stem cells (hiPSC) from seven patients harboring mutations across the DMD gene. Mutations were retained during differentiation and analysis indicated the cardiomyocytes showed a dystrophic gene expression profile. Antisense oligonucleotide-mediated skipping of exon 51 restored dystrophin expression to ∼30% of normal levels in hiPSC-cardiomyocytes carrying exon 47–50 or 48–50 deletions. Alternatively, delivery of a dystrophin minigene to cardiomyocytes with a deletion in exon 35 or a point mutation in exon 70 allowed expression levels similar to those seen in healthy cells. This demonstrates that DMD hiPSC-cardiomyocytes provide a novel tool to evaluate whether new therapeutics can restore dystrophin expression in the heart. PMID:23829870

  3. Electromechanical Conditioning of Adult Progenitor Cells Improves Recovery of Cardiac Function After Myocardial Infarction.

    PubMed

    Llucià-Valldeperas, Aida; Soler-Botija, Carolina; Gálvez-Montón, Carolina; Roura, Santiago; Prat-Vidal, Cristina; Perea-Gil, Isaac; Sanchez, Benjamin; Bragos, Ramon; Vunjak-Novakovic, Gordana; Bayes-Genis, Antoni

    2017-03-01

    Cardiac cells are subjected to mechanical and electrical forces, which regulate gene expression and cellular function. Therefore, in vitro electromechanical stimuli could benefit further integration of therapeutic cells into the myocardium. Our goals were (a) to study the viability of a tissue-engineered construct with cardiac adipose tissue-derived progenitor cells (cardiac ATDPCs) and (b) to examine the effect of electromechanically stimulated cardiac ATDPCs within a myocardial infarction (MI) model in mice for the first time. Cardiac ATDPCs were electromechanically stimulated at 2-millisecond pulses of 50 mV/cm at 1 Hz and 10% stretching during 7 days. The cells were harvested, labeled, embedded in a fibrin hydrogel, and implanted over the infarcted area of the murine heart. A total of 39 animals were randomly distributed and sacrificed at 21 days: groups of grafts without cells and with stimulated or nonstimulated cells. Echocardiography and gene and protein analyses were also carried out. Physiologically stimulated ATDPCs showed increased expression of cardiac transcription factors, structural genes, and calcium handling genes. At 21 days after implantation, cardiac function (measured as left ventricle ejection fraction between presacrifice and post-MI) increased up to 12% in stimulated grafts relative to nontreated animals. Vascularization and integration with the host blood supply of grafts with stimulated cells resulted in increased vessel density in the infarct border region. Trained cells within the implanted fibrin patch expressed main cardiac markers and migrated into the underlying ischemic myocardium. To conclude, synchronous electromechanical cell conditioning before delivery may be a preferred alternative when considering strategies for heart repair after myocardial infarction. Stem Cells Translational Medicine 2017;6:970-981.

  4. Induced pluripotent stem cells as a new strategy for cardiac regeneration and disease modeling.

    PubMed

    Iglesias-García, Olalla; Pelacho, Beatriz; Prósper, Felipe

    2013-09-01

    The possibility to induce pluripotency in somatic cells or, even further, to induce cell transdifferentiation through the forced expression of reprogramming factors has offered new, attractive options for cardiovascular regenerative medicine. In fact, recent discoveries have demonstrated that induced pluripotent stem (iPS) cells can be differentiated into cardiomyocytes, suggesting that iPS cells have the potential to significantly advance future cardiac regenerative therapies. Herein, we provide an overview of the characteristics and differentiation potential associated with iPS cells. In addition, we discuss current methods for inducing their specification towards a cardiovascular phenotype as well as in vivo evidence supporting the therapeutic benefit of iPS-derived cardiac cells. Finally, we describe recent findings regarding the use of iPS-derived cells for modeling several genetic cardiac disorders, which have indicated that these pluripotent cells represent an ideal tool for drug testing and might contribute to the development of future personalized regenerative cell therapies.

  5. Stem Cell Technology in Cardiac Regeneration: A Pluripotent Stem Cell Promise.

    PubMed

    Duelen, Robin; Sampaolesi, Maurilio

    2017-01-27

    Despite advances in cardiovascular biology and medical therapy, heart disorders are the leading cause of death worldwide. Cell-based regenerative therapies become a promising treatment for patients affected by heart failure, but also underline the need for reproducible results in preclinical and clinical studies for safety and efficacy. Enthusiasm has been tempered by poor engraftment, survival and differentiation of the injected adult stem cells. The crucial challenge is identification and selection of the most suitable stem cell type for cardiac regenerative medicine. Human pluripotent stem cells (PSCs) have emerged as attractive cell source to obtain cardiomyocytes (CMs), with potential applications, including drug discovery and toxicity screening, disease modelling and innovative cell therapies. Lessons from embryology offered important insights into the development of stem cell-derived CMs. However, the generation of a CM population, uniform in cardiac subtype, adult maturation and functional properties, is highly recommended. Moreover, hurdles regarding tumorigenesis, graft cell death, immune rejection and arrhythmogenesis need to be overcome in clinical practice. Here we highlight the recent progression in PSC technologies for the regeneration of injured heart. We review novel strategies that might overcome current obstacles in heart regenerative medicine, aiming at improving cell survival and functional integration after cell transplantation.

  6. Developmental stage-dependent effects of cardiac fibroblasts on function of stem cell-derived engineered cardiac tissues

    PubMed Central

    Liau, Brian; Jackman, Christopher P.; Li, Yanzhen; Bursac, Nenad

    2017-01-01

    We investigated whether the developmental stage of mouse cardiac fibroblasts (CFs) influences the formation and function of engineered cardiac tissues made of mouse embryonic stem cell-derived cardiomyocytes (mESC-CMs). Engineered cardiac tissue patches were fabricated by encapsulating pure mESC-CMs, mESC-CMs + adult CFs, or mESC-CMs + fetal CFs in fibrin-based hydrogel. Tissue patches containing fetal CFs exhibited higher velocity of action potential propagation and contractile force amplitude compared to patches containing adult CFs, while pure mESC-CM patches did not form functional syncytium. The functional improvements in mESC-CM + fetal CF patches were associated with differences in structural remodeling and increased expression of proteins involved in cardiac function. To determine role of paracrine signaling, we cultured pure mESC-CMs within miniature tissue “micro-patches” supplemented with media conditioned by adult or fetal CFs. Fetal CF-conditioned media distinctly enhanced CM spreading and contractile activity, which was shown by pathway inhibitor experiments and Western blot analysis to be mediated via MEK-ERK signaling. In mESC-CM monolayers, CF-conditioned media did not alter CM spreading or MEK-ERK activation. Collectively, our studies show that 3D co-culture of mESC-CMs with embryonic CFs is superior to co-culture with adult CFs for in vitro generation of functional myocardium. Ensuring consistent developmental stages of cardiomyocytes and supporting non-myocytes may be a critical factor for promoting functional maturation of engineered cardiac tissues. PMID:28181589

  7. Hyperglycemic and Hyperlipidemic Conditions Alter Cardiac Cell Biomechanical Properties

    PubMed Central

    Michaelson, Jarett; Hariharan, Venkatesh; Huang, Hayden

    2014-01-01

    Currently, many diabetic cardiomyopathy (DC) studies focus on either in vitro molecular pathways or in vivo whole-heart properties such as ejection fraction. However, as DC is primarily a disease caused by changes in structural and functional properties, such studies may not precisely identify the influence of hyperglycemia or hyperlipidemia in producing specific cellular changes, such as increased myocardial stiffness or diastolic dysfunction. To address this need, we developed an in vitro approach to examine how structural and functional properties may change as a result of a diabetic environment. Particle-tracking microrheology was used to characterize the biomechanical properties of cardiac myocytes and fibroblasts under hyperglycemia or hyperlipidemic conditions. We showed that myocytes, but not fibroblasts, exhibited increased stiffness under diabetic conditions. Hyperlipidemia, but not hyperglycemia, led to increased cFos expression. Although direct application of reactive oxygen species had only limited effects that altered myocyte properties, the antioxidant N-acetylcysteine had broader effects in limiting glucose or fatty-acid alterations. Changes consistent with clinical DC alterations occur in cells cultured in elevated glucose or fatty acids. However, the individual roles of glucose, reactive oxygen species, and fatty acids are varied, suggesting multiple pathway involvement. PMID:24896111

  8. Hyperglycemic and hyperlipidemic conditions alter cardiac cell biomechanical properties.

    PubMed

    Michaelson, Jarett; Hariharan, Venkatesh; Huang, Hayden

    2014-06-03

    Currently, many diabetic cardiomyopathy (DC) studies focus on either in vitro molecular pathways or in vivo whole-heart properties such as ejection fraction. However, as DC is primarily a disease caused by changes in structural and functional properties, such studies may not precisely identify the influence of hyperglycemia or hyperlipidemia in producing specific cellular changes, such as increased myocardial stiffness or diastolic dysfunction. To address this need, we developed an in vitro approach to examine how structural and functional properties may change as a result of a diabetic environment. Particle-tracking microrheology was used to characterize the biomechanical properties of cardiac myocytes and fibroblasts under hyperglycemia or hyperlipidemic conditions. We showed that myocytes, but not fibroblasts, exhibited increased stiffness under diabetic conditions. Hyperlipidemia, but not hyperglycemia, led to increased cFos expression. Although direct application of reactive oxygen species had only limited effects that altered myocyte properties, the antioxidant N-acetylcysteine had broader effects in limiting glucose or fatty-acid alterations. Changes consistent with clinical DC alterations occur in cells cultured in elevated glucose or fatty acids. However, the individual roles of glucose, reactive oxygen species, and fatty acids are varied, suggesting multiple pathway involvement.

  9. Primary cardiac B cell lymphoma: Manifestation of Felty's syndrome or TNFα antagonist.

    PubMed

    Benzerdjeb, Nazim; Ameur, Fatima; Ikoli, Jean-Fortune; Sevestre, Henri

    2016-12-01

    Primary cardiac B cell lymphoma is rare. To date, fewer than 90 cases have been described in the literature. We report a 67-year-old woman with a 30-year history of rheumatoid arthritis, who had received treatment with leflunomide for 10 years and infliximab for 2 years. Secondary Felty's syndrome appeared. She was admitted to the hospital for abdominal pain. Investigations disclosed a 5cm cardiac mass in the right atrium. Histopathologic examination of tissue specimens obtained at surgical myocardial biopsy demonstrated primary cardiac B cell lymphoma. The other iatrogenic lymphoproliferative disorders are reviewed. This lesion might be a manifestation of long term TNFα antagonists treatment.

  10. Paracrine Engineering of Human Explant-Derived Cardiac Stem Cells to Over-Express Stromal-Cell Derived Factor 1α Enhances Myocardial Repair.

    PubMed

    Tilokee, Everad L; Latham, Nicholas; Jackson, Robyn; Mayfield, Audrey E; Ye, Bin; Mount, Seth; Lam, Buu-Khanh; Suuronen, Erik J; Ruel, Marc; Stewart, Duncan J; Davis, Darryl R

    2016-07-01

    First generation cardiac stem cell products provide indirect cardiac repair but variably produce key cardioprotective cytokines, such as stromal-cell derived factor 1α, which opens the prospect of maximizing up-front paracrine-mediated repair. The mesenchymal subpopulation within explant derived human cardiac stem cells underwent lentiviral mediated gene transfer of stromal-cell derived factor 1α. Unlike previous unsuccessful attempts to increase efficacy by boosting the paracrine signature of cardiac stem cells, cytokine profiling revealed that stromal-cell derived factor 1α over-expression prevented lv-mediated "loss of cytokines" through autocrine stimulation of CXCR4+ cardiac stem cells. Stromal-cell derived factor 1α enhanced angiogenesis and stem cell recruitment while priming cardiac stem cells to readily adopt a cardiac identity. As compared to injection with unmodified cardiac stem cells, transplant of stromal-cell derived factor 1α enhanced cells into immunodeficient mice improved myocardial function and angiogenesis while reducing scarring. Increases in myocardial stromal-cell derived factor 1α content paralleled reductions in myocyte apoptosis but did not influence long-term engraftment or the fate of transplanted cells. Transplantation of stromal-cell derived factor 1α transduced cardiac stem cells increased the generation of new myocytes, recruitment of bone marrow cells, new myocyte/vessel formation and the salvage of reversibly damaged myocardium to enhance cardiac repair after experimental infarction. Stem Cells 2016;34:1826-1835.

  11. Cobalt chloride pretreatment promotes cardiac differentiation of human embryonic stem cells under atmospheric oxygen level.

    PubMed

    Ng, Kwong-Man; Chan, Yau-Chi; Lee, Yee-Ki; Lai, Wing-Hon; Au, Ka-Wing; Fung, Man-Lung; Siu, Chung-Wah; Li, Ronald A; Tse, Hung-Fat

    2011-12-01

    Our previous study demonstrated the direct involvement of the HIF-1α subunit in the promotion of cardiac differentiation of murine embryonic stem cells (ESCs). We report the use of cobalt chloride to induce HIF-1α stabilization in human ESCs to promote cardiac differentiation. Treatment of undifferentiated hES2 human ESCs with 50 μM cobalt chloride markedly increased protein levels of the HIF-1α subunit, and was associated with increased expression of early cardiac specific transcription factors and cardiotrophic factors including NK2.5, vascular endothelial growth factor, and cardiotrophin-1. When pretreated cells were subjected to cardiac differentiation, a notable increase in the occurrence of beating embryoid bodies and sarcomeric actinin-positive cells was observed, along with increased expression of the cardiac-specific markers, MHC-A, MHC-B, and MLC2V. Electrophysiological study revealed increased atrial- and nodal-like cells in the cobalt chloride-pretreated group. Confocal calcium imaging analysis indicated that the maximum upstroke and decay velocities were significantly increased in both noncaffeine and caffeine-induced calcium transient in cardiomyocytes derived from the cobalt chloride-pretreated cells, suggesting these cells were functionally more mature. In conclusion, our study demonstrated that cobalt chloride pretreatment of hES2 human ESCs promotes cardiac differentiation and the maturation of calcium homeostasis of cardiomyocytes derived from ESCs.

  12. Tbx18-dependent differentiation of brown adipose tissue-derived stem cells toward cardiac pacemaker cells.

    PubMed

    Chen, Lei; Deng, Zi-Jun; Zhou, Jian-Sheng; Ji, Rui-Juan; Zhang, Xi; Zhang, Chuan-Sen; Li, Yu-Quan; Yang, Xiang-Qun

    2017-04-05

    A cell-sourced biological pacemaker is a promising therapeutic approach for sick sinus syndrome (SSS) or severe atrial ventricular block (AVB). Adipose tissue-derived stem cells (ATSCs), which are optimal candidate cells for possible use in regenerative therapy for acute or chronic myocardial injury, have the potential to differentiate into spontaneous beating cardiomyocytes. However, the pacemaker characteristics of the beating cells need to be confirmed, and little is known about the underlying differential mechanism. In this study, we found that brown adipose tissue-derived stem cells (BATSCs) in mice could differentiate into spontaneous beating cells in 15% FBS Dulbecco's modified Eagle's medium (DMEM) without additional treatment. Subsequently, we provide additional evidence, including data regarding ultrastructure, protein expression, electrophysiology, and pharmacology, to support the differentiation of BATSCs into a cardiac pacemaker phenotype during the course of early cultivation. Furthermore, we found that silencing Tbx18, a key transcription factor in the development of pacemaker cells, terminated the differentiation of BATSCs into a pacemaker phenotype, suggesting that Tbx18 is required to direct BATSCs toward a cardiac pacemaker fate. The expression of Tbx3 and shox2, the other two important transcription factors in the development of pacemaker cells, was decreased by silencing Tbx18, which suggests that Tbx18 mediates the differentiation of BATSCs into a pacemaker phenotype via these two downstream transcription factors.

  13. Targeted deletion of Hand2 in cardiac neural crest-derived cells influences cardiac gene expression and outflow tract development

    PubMed Central

    Holler, Kristen L.; Hendershot, Tyler J.; Troy, Sophia E.; Vincentz, Joshua W.; Firulli, Anthony B.; Howard, Marthe J.

    2010-01-01

    The basic helix-loop-helix DNA binding protein Hand2 has critical functions in cardiac development both in neural crest-derived and mesoderm-derived structures. Targeted deletion of Hand2 in the neural crest has allowed us to genetically dissect Hand2-dependent defects specifically in outflow tract and cardiac cushion independent of Hand2 functions in mesoderm-derived structures. Targeted deletion of Hand2 in the neural crest results in misalignment of the aortic arch arteries and outflow tract, contributing to development of double outlet right ventricle (DORV) and ventricular septal defects (VSD). These neural crest-derived developmental anomalies are associated with altered expression of Hand2-target genes we have identified by gene profiling. A number of Hand2 direct target genes have been identified using ChIP and ChIP-on-chip analyses. We have identified and validated a number of genes related to cell migration, proliferation/cell cycle and intracellular signaling whose expression is affected by Hand2 deletion in the neural crest and which are associated with development of VSD and DORV. Our data suggest that Hand2 is a multifunctional DNA binding protein affecting expression of target genes associated with a number of functional interactions in neural crest-derived cells required for proper patterning of the outflow tract, generation of the appropriate number of neural crest-derived cells for elongation of the conotruncus and cardiac cushion organization. Our genetic model has made it possible to investigate the molecular genetics of neural crest contributions to outflow tract morphogenesis and cell differentiation. PMID:20144608

  14. Cardiac regeneration using pluripotent stem cells--progression to large animal models.

    PubMed

    Chong, James J H; Murry, Charles E

    2014-11-01

    Pluripotent stem cells (PSCs) have indisputable cardiomyogenic potential and therefore have been intensively investigated as a potential cardiac regenerative therapy. Current directed differentiation protocols are able to produce high yields of cardiomyocytes from PSCs and studies in small animal models of cardiovascular disease have proven sustained engraftment and functional efficacy. Therefore, the time is ripe for cardiac regenerative therapies using PSC derivatives to be tested in large animal models that more closely resemble the hearts of humans. In this review, we discuss the results of our recent study using human embryonic stem cell derived cardiomyocytes (hESC-CM) in a non-human primate model of ischemic cardiac injury. Large scale remuscularization, electromechanical coupling and short-term arrhythmias demonstrated by our hESC-CM grafts are discussed in the context of other studies using adult stem cells for cardiac regeneration.

  15. Recent Insights in the Paracrine Modulation of Cardiomyocyte Contractility by Cardiac Endothelial Cells

    PubMed Central

    Andriantsitohaina, Ramaroson

    2014-01-01

    The cardiac endothelium is formed by a continuous monolayer of cells that line the cavity of the heart (endocardial endothelial cells (EECs)) and the luminal surface of the myocardial blood vessels (intramyocardial capillary endothelial cells (IMCEs)). EECs and IMCEs can exercise substantial control over the contractility of cardiomyocytes by releasing various factors such as nitric oxide (NO) via a constitutive endothelial NO-synthase (eNOS), endothelin-1, prostaglandins, angiotensin II, peptide growth factors, and neuregulin-1. The purpose of the present paper is actually to shortly review recent new information concerning cardiomyocytes as effectors of endothelium paracrine signaling, focusing particularly on contractile function. The modes of action and the regulatory paracrine role of the main mediators delivered by cardiac endothelial cells upon cardiac contractility identified in cardiomyocytes are complex and not fully described. Thus, careful evaluation of new therapeutic approaches is required targeting important physiological signaling pathways, some of which have been until recently considered as deleterious, like reactive oxygen species. Future works in the field of cardiac endothelial cells and cardiac function will help to better understand the implication of these mediators in cardiac physiopathology. PMID:24745027

  16. Cardiac tissue engineering in magnetically actuated scaffolds

    NASA Astrophysics Data System (ADS)

    Sapir, Yulia; Polyak, Boris; Cohen, Smadar

    2014-01-01

    Cardiac tissue engineering offers new possibilities for the functional and structural restoration of damaged or lost heart tissue by applying cardiac patches created in vitro. Engineering such functional cardiac patches is a complex mission, involving material design on the nano- and microscale as well as the application of biological cues and stimulation patterns to promote cell survival and organization into a functional cardiac tissue. Herein, we present a novel strategy for creating a functional cardiac patch by combining the use of a macroporous alginate scaffold impregnated with magnetically responsive nanoparticles (MNPs) and the application of external magnetic stimulation. Neonatal rat cardiac cells seeded within the magnetically responsive scaffolds and stimulated by an alternating magnetic field of 5 Hz developed into matured myocardial tissue characterized by anisotropically organized striated cardiac fibers, which preserved its features for longer times than non-stimulated constructs. A greater activation of AKT phosphorylation in cardiac cell constructs after applying a short-term (20 min) external magnetic field indicated the efficacy of magnetic stimulation to actuate at a distance and provided a possible mechanism for its action. Our results point to a synergistic effect of magnetic field stimulation together with nanoparticulate features of the scaffold surface as providing the regenerating environment for cardiac cells driving their organization into functionally mature tissue.

  17. Magnetic Resonance Imaging of Iron Oxide-Labeled Human Embryonic Stem Cell-Derived Cardiac Progenitors

    PubMed Central

    Skelton, Rhys J.P.; Khoja, Suhail; Almeida, Shone; Rapacchi, Stanislas; Han, Fei; Engel, James; Zhao, Peng; Hu, Peng; Stanley, Edouard G.; Elefanty, Andrew G.; Kwon, Murray

    2016-01-01

    Given the limited regenerative capacity of the heart, cellular therapy with stem cell-derived cardiac cells could be a potential treatment for patients with heart disease. However, reliable imaging techniques to longitudinally assess engraftment of the transplanted cells are scant. To address this issue, we used ferumoxytol as a labeling agent of human embryonic stem cell-derived cardiac progenitor cells (hESC-CPCs) to facilitate tracking by magnetic resonance imaging (MRI) in a large animal model. Differentiating hESCs were exposed to ferumoxytol at different time points and varying concentrations. We determined that treatment with ferumoxytol at 300 μg/ml on day 0 of cardiac differentiation offered adequate cell viability and signal intensity for MRI detection without compromising further differentiation into definitive cardiac lineages. Labeled hESC-CPCs were transplanted by open surgical methods into the left ventricular free wall of uninjured pig hearts and imaged both ex vivo and in vivo. Comprehensive T2*-weighted images were obtained immediately after transplantation and 40 days later before termination. The localization and dispersion of labeled cells could be effectively imaged and tracked at days 0 and 40 by MRI. Thus, under the described conditions, ferumoxytol can be used as a long-term, differentiation-neutral cell-labeling agent to track transplanted hESC-CPCs in vivo using MRI. Significance The development of a safe and reproducible in vivo imaging technique to track the fate of transplanted human embryonic stem cell-derived cardiac progenitor cells (hESC-CPCs) is a necessary step to clinical translation. An iron oxide nanoparticle (ferumoxytol)-based approach was used for cell labeling and subsequent in vivo magnetic resonance imaging monitoring of hESC-CPCs transplanted into uninjured pig hearts. The present results demonstrate the use of ferumoxytol labeling and imaging techniques in tracking the location and dispersion of cell grafts

  18. The effect of encapsulation of cardiac stem cells within matrix-enriched hydrogel capsules on cell survival, post-ischemic cell retention and cardiac function.

    PubMed

    Mayfield, Audrey E; Tilokee, Everad L; Latham, Nicholas; McNeill, Brian; Lam, Bu-Khanh; Ruel, Marc; Suuronen, Erik J; Courtman, David W; Stewart, Duncan J; Davis, Darryl R

    2014-01-01

    Transplantation of ex vivo proliferated cardiac stem cells (CSCs) is an emerging therapy for ischemic cardiomyopathy but outcomes are limited by modest engraftment and poor long-term survival. As such, we explored the effect of single cell microencapsulation to increase CSC engraftment and survival after myocardial injection. Transcript and protein profiling of human atrial appendage sourced CSCs revealed strong expression the pro-survival integrin dimers αVβ3 and α5β1- thus rationalizing the integration of fibronectin and fibrinogen into a supportive intra-capsular matrix. Encapsulation maintained CSC viability under hypoxic stress conditions and, when compared to standard suspended CSC, media conditioned by encapsulated CSCs demonstrated superior production of pro-angiogenic/cardioprotective cytokines, angiogenesis and recruitment of circulating angiogenic cells. Intra-myocardial injection of encapsulated CSCs after experimental myocardial infarction favorably affected long-term retention of CSCs, cardiac structure and function. Single cell encapsulation prevents detachment induced cell death while boosting the mechanical retention of CSCs to enhance repair of damaged myocardium.

  19. Evidence for a discrete UTP receptor in cardiac endothelial cells.

    PubMed Central

    Yang, S.; Buxton, I. L.; Probert, C. B.; Talbot, J. N.; Bradley, M. E.

    1996-01-01

    1. We have examined the effects of various purine and pyrimidine nucleotides upon cells cultured from guinea-pig cardiac endothelium (CEC), and find the P2Y-agonist 2-methylthioadenosine triphosphate (2MeSATP) to be a potent (EC50 = 85 +/- 10.2 nM) stimulator of increase in intracellular calcium concentrations, while uridine 5'-triphosphate (UTP) and adenosine 5'-triphosphate (ATP) are less potent but equipotent with one another (EC50s = 2.1 +/- 0.3 and 1.8 +/- 0.2 microM, respectively). 2. While the P2Y receptor exhibited rapid homologous desensitization, this had no effect upon subsequent responsiveness of CEC to either ATP or UTP. Effects of maximal concentrations of ATP and UTP were not only additive, but did not cross-desensitize. Responses to UTP (but not to ATP or 2MeSATP) were blocked by treatment with pertussis toxin (PTX); all three nucleotides appeared to liberate calcium from an intracellular pool. 3. Suramin (30 microM) significantly (P < 0.05) increased the EC50 for ATP-dependent increases in intracellular calcium (5.3 +/- 2.2 microM vs. 2.0 +/- 0.9 microM in the absence of suramin), while it completely blocked the response to 2MeSATP. Suramin had no effect upon responses to UTP at concentrations of 100 microM. 4. We conclude that in addition to the P2Y and P2U subtypes of the ATP receptor, an additional receptor responsive to UTP but exhibiting no affinity for purine nucleotides is present in CEC; this "pyrimidine receptor' liberates intracellular calcium via a G-protein, and may partly mediate the contractile response to UTP in the coronary vasculature. PMID:8730756

  20. Gene Therapy Restores Hair Cell Stereocilia Morphology in Inner Ears of Deaf Whirler Mice.

    PubMed

    Chien, Wade W; Isgrig, Kevin; Roy, Soumen; Belyantseva, Inna A; Drummond, Meghan C; May, Lindsey A; Fitzgerald, Tracy S; Friedman, Thomas B; Cunningham, Lisa L

    2016-02-01

    Hereditary deafness is one of the most common disabilities affecting newborns. Many forms of hereditary deafness are caused by morphological defects of the stereocilia bundles on the apical surfaces of inner ear hair cells, which are responsible for sound detection. We explored the effectiveness of gene therapy in restoring the hair cell stereocilia architecture in the whirlin mouse model of human deafness, which is deaf due to dysmorphic, short stereocilia. Wild-type whirlin cDNA was delivered via adeno-associated virus (AAV8) by injection through the round window of the cochleas in neonatal whirler mice. Subsequently, whirlin expression was detected in infected hair cells (IHCs), and normal stereocilia length and bundle architecture were restored. Whirlin gene therapy also increased inner hair cell survival in the treated ears compared to the contralateral nontreated ears. These results indicate that a form of inherited deafness due to structural defects in cochlear hair cells is amenable to restoration through gene therapy.

  1. Inscribing Optical Excitability to Non-Excitable Cardiac Cells: Viral Delivery of Optogenetic Tools in Primary Cardiac Fibroblasts.

    PubMed

    Yu, Jinzhu; Entcheva, Emilia

    2016-01-01

    We describe in detail a method to introduce optogenetic actuation tools, a mutant version of channelrhodopsin-2, ChR2(H134R), and archaerhodopsin (ArchT), into primary cardiac fibroblasts (cFB) in vitro by adenoviral infection to yield quick, robust, and consistent expression. Instructions on adjusting infection parameters such as the multiplicity of infection and virus incubation duration are provided to generalize the method for different lab settings or cell types. Specific conditions are discussed to create hybrid co-cultures of the optogenetically modified cFB and non-transformed cardiomyocytes to obtain light-sensitive excitable cardiac syncytium, including stencil-patterned cell growth. We also describe an all-optical framework for the functional testing of responsiveness of these opsins in cFB. The presented methodology provides cell-specific tools for the mechanistic investigation of the functional bioelectric contribution of different non-excitable cells in the heart and their electrical coupling to cardiomyocytes under different conditions.

  2. Inscribing Optical Excitability to Non-Excitable Cardiac Cells: Viral Delivery of Optogenetic Tools in Primary Cardiac Fibroblasts

    PubMed Central

    Yu, Jinzhu; Entcheva, Emilia

    2016-01-01

    We describe in detail a method to introduce optogenetic actuation tools, a mutant version of channelrhodopsin- 2, ChR2(H134R), and archaerhodopsin (ArchT), into primary cardiac fibroblasts (cFB) in vitro by adenoviral infection to yield quick, robust, and consistent expression. Instructions on adjusting infection parameters such as the multiplicity of infection and virus incubation duration are provided to generalize the method for different lab settings or cell types. Specific conditions are discussed to create hybrid co-cultures of the optogenetically modified cFB and non-transformed cardiomyocytes to obtain light- sensitive excitable cardiac syncytium, including stencil-patterned cell growth. We also describe an all-optical framework for the functional testing of responsiveness of these opsins in cFB. The presented methodology provides cell-specific tools for the mechanistic investigation of the functional bioelectric contribution of different non-excitable cells in the heart and their electrical coupling to cardiomyocytes under different conditions. PMID:26965132

  3. The Histone Methyltransferase Inhibitor BIX01294 Enhances the Cardiac Potential of Bone Marrow Cells

    PubMed Central

    Mezentseva, Nadejda V.; Yang, Jinpu; Kaur, Keerat; Iaffaldano, Grazia; Rémond, Mathieu C.; Eisenberg, Carol A.

    2013-01-01

    Bone marrow (BM) has long been considered a potential stem cell source for cardiac repair due to its abundance and accessibility. Although previous investigations have generated cardiomyocytes from BM, yields have been low, and far less than produced from ES or induced pluripotent stem cells (iPSCs). Since differentiation of pluripotent cells is difficult to control, we investigated whether BM cardiac competency could be enhanced without making cells pluripotent. From screens of various molecules that have been shown to assist iPSC production or maintain the ES cell phenotype, we identified the G9a histone methyltransferase inhibitor BIX01294 as a potential reprogramming agent for converting BM cells to a cardiac-competent phenotype. BM cells exposed to BIX01294 displayed significantly elevated expression of brachyury, Mesp1, and islet1, which are genes associated with embryonic cardiac progenitors. In contrast, BIX01294 treatment minimally affected ectodermal, endodermal, and pluripotency gene expression by BM cells. Expression of cardiac-associated genes Nkx2.5, GATA4, Hand1, Hand2, Tbx5, myocardin, and titin was enhanced 114, 76, 276, 46, 635, 123, and 5-fold in response to the cardiogenic stimulator Wnt11 when BM cells were pretreated with BIX01294. Immunofluorescent analysis demonstrated that BIX01294 exposure allowed for the subsequent display of various muscle proteins within the cells. The effect of BIX01294 on the BM cell phenotype and differentiation potential corresponded to an overall decrease in methylation of histone H3 at lysine9, which is the primary target of G9a histone methyltransferase. In summary, these data suggest that BIX01294 inhibition of chromatin methylation reprograms BM cells to a cardiac-competent progenitor phenotype. PMID:22994322

  4. The histone methyltransferase inhibitor BIX01294 enhances the cardiac potential of bone marrow cells.

    PubMed

    Mezentseva, Nadejda V; Yang, Jinpu; Kaur, Keerat; Iaffaldano, Grazia; Rémond, Mathieu C; Eisenberg, Carol A; Eisenberg, Leonard M

    2013-02-15

    Bone marrow (BM) has long been considered a potential stem cell source for cardiac repair due to its abundance and accessibility. Although previous investigations have generated cardiomyocytes from BM, yields have been low, and far less than produced from ES or induced pluripotent stem cells (iPSCs). Since differentiation of pluripotent cells is difficult to control, we investigated whether BM cardiac competency could be enhanced without making cells pluripotent. From screens of various molecules that have been shown to assist iPSC production or maintain the ES cell phenotype, we identified the G9a histone methyltransferase inhibitor BIX01294 as a potential reprogramming agent for converting BM cells to a cardiac-competent phenotype. BM cells exposed to BIX01294 displayed significantly elevated expression of brachyury, Mesp1, and islet1, which are genes associated with embryonic cardiac progenitors. In contrast, BIX01294 treatment minimally affected ectodermal, endodermal, and pluripotency gene expression by BM cells. Expression of cardiac-associated genes Nkx2.5, GATA4, Hand1, Hand2, Tbx5, myocardin, and titin was enhanced 114, 76, 276, 46, 635, 123, and 5-fold in response to the cardiogenic stimulator Wnt11 when BM cells were pretreated with BIX01294. Immunofluorescent analysis demonstrated that BIX01294 exposure allowed for the subsequent display of various muscle proteins within the cells. The effect of BIX01294 on the BM cell phenotype and differentiation potential corresponded to an overall decrease in methylation of histone H3 at lysine9, which is the primary target of G9a histone methyltransferase. In summary, these data suggest that BIX01294 inhibition of chromatin methylation reprograms BM cells to a cardiac-competent progenitor phenotype.

  5. Injection of vessel-derived stem cells prevents dilated cardiomyopathy and promotes angiogenesis and endogenous cardiac stem cell proliferation in mdx/utrn-/- but not aged mdx mouse models for duchenne muscular dystrophy.

    PubMed

    Chun, Ju Lan; O'Brien, Robert; Song, Min Ho; Wondrasch, Blake F; Berry, Suzanne E

    2013-01-01

    Duchenne muscular dystrophy (DMD) is the most common form of muscular dystrophy. DMD patients lack dystrophin protein and develop skeletal muscle pathology and dilated cardiomyopathy (DCM). Approximately 20% succumb to cardiac involvement. We hypothesized that mesoangioblast stem cells (aorta-derived mesoangioblasts [ADMs]) would restore dystrophin and alleviate or prevent DCM in animal models of DMD. ADMs can be induced to express cardiac markers, including Nkx2.5, cardiac tropomyosin, cardiac troponin I, and α-actinin, and adopt cardiomyocyte morphology. Transplantation of ADMs into the heart of mdx/utrn(-/-) mice prior to development of DCM prevented onset of cardiomyopathy, as measured by echocardiography, and resulted in significantly higher CD31 expression, consistent with new vessel formation. Dystrophin-positive cardiomyocytes and increased proliferation of endogenous Nestin(+) cardiac stem cells were detected in ADM-injected heart. Nestin(+) striated cells were also detected in four of five mdx/utrn(-/-) hearts injected with ADMs. In contrast, when ADMs were injected into the heart of aged mdx mice with advanced fibrosis, no functional improvement was detected by echocardiography. Instead, ADMs exacerbated some features of DCM. No dystrophin protein, increase in CD31 expression, or increase in Nestin(+) cell proliferation was detected following ADM injection in aged mdx heart. Dystrophin was observed following transplantation of ADMs into the hearts of young mdx mice, however, suggesting that pathology in aged mdx heart may alter the fate of donor stem cells. In summary, ADMs delay or prevent development of DCM in dystrophin-deficient heart, but timing of stem cell transplantation may be critical for achieving benefit with cell therapy in DMD cardiac muscle.

  6. Recent Stem Cell Advances: Cord Blood and Induced Pluripotent Stem Cell for Cardiac Regeneration- a Review

    PubMed Central

    Medhekar, Sheetal Kashinath; Shende, Vikas Suresh; Chincholkar, Anjali Baburao

    2016-01-01

    Stem cells are primitive self renewing undifferentiated cell that can be differentiated into various types of specialized cells like nerve cell, skin cells, muscle cells, intestinal tissue, and blood cells. Stem cells live in bone marrow where they divide to make new blood cells and produces peripheral stem cells in circulation. Under proper environment and in presence of signaling molecules stem cells begin to develop into specialized tissues and organs. These unique characteristics make them very promising entities for regeneration of damaged tissue. Day by day increase in incidence of heart diseases including left ventricular dysfunction, ischemic heart disease (IHD), congestive heart failure (CHF) are the major cause of morbidity and mortality. However infracted tissue cannot regenerate into healthy tissue. Heart transplantation is only the treatment for such patient. Due to limitation of availability of donor for organ transplantation, a focus is made for alternative and effective therapy to treat such condition. In this review we have discussed the new advances in stem cells such as use of cord stem cells and iPSC technology in cardiac repair. Future approach of CB cells was found to be used in tissue repair which is specifically observed for improvement of left ventricular function and myocardial infarction. Here we have also focused on how iPSC technology is used for regeneration of cardiomyocytes and intiating neovascularization in myocardial infarction and also for study of pathophysiology of various degenerative diseases and genetic disease in research field. PMID:27426082

  7. Recent Stem Cell Advances: Cord Blood and Induced Pluripotent Stem Cell for Cardiac Regeneration- a Review.

    PubMed

    Medhekar, Sheetal Kashinath; Shende, Vikas Suresh; Chincholkar, Anjali Baburao

    2016-05-30

    Stem cells are primitive self renewing undifferentiated cell that can be differentiated into various types of specialized cells like nerve cell, skin cells, muscle cells, intestinal tissue, and blood cells. Stem cells live in bone marrow where they divide to make new blood cells and produces peripheral stem cells in circulation. Under proper environment and in presence of signaling molecules stem cells begin to develop into specialized tissues and organs. These unique characteristics make them very promising entities for regeneration of damaged tissue. Day by day increase in incidence of heart diseases including left ventricular dysfunction, ischemic heart disease (IHD), congestive heart failure (CHF) are the major cause of morbidity and mortality. However infracted tissue cannot regenerate into healthy tissue. Heart transplantation is only the treatment for such patient. Due to limitation of availability of donor for organ transplantation, a focus is made for alternative and effective therapy to treat such condition. In this review we have discussed the new advances in stem cells such as use of cord stem cells and iPSC technology in cardiac repair. Future approach of CB cells was found to be used in tissue repair which is specifically observed for improvement of left ventricular function and myocardial infarction. Here we have also focused on how iPSC technology is used for regeneration of cardiomyocytes and intiating neovascularization in myocardial infarction and also for study of pathophysiology of various degenerative diseases and genetic disease in research field.

  8. Erythropoietin protects myocardin-expressing cardiac stem cells against cytotoxicity of tumor necrosis factor-{alpha}

    SciTech Connect

    Madonna, Rosalinda; Shelat, Harnath; Xue, Qun; Willerson, James T.; De Caterina, Raffaele; Geng, Yong-Jian

    2009-10-15

    Cardiac stem cells are vulnerable to inflammation caused by infarction or ischemic injury. The growth factor, erythropoietin (Epo), ameliorates the inflammatory response of the myocardium to ischemic injury. This study was designed to assess the role of Epo in regulation of expression and activation of the cell death-associated intracellular signaling components in cardiac myoblasts stimulated with the proinflammatory cytokine tumor necrosis factor (TNF)-{alpha}. Cardiac myoblasts isolated from canine embryonic hearts characterized by expression of myocardin A, a promyogenic transcription factor for cardiovascular muscle development were pretreated with Epo and then exposed to TNF-{alpha}. Compared to untreated cells, the Epo-treated cardiac myoblasts exhibited better morphology and viability. Immunoblotting revealed lower levels of active caspase-3 and reductions in iNOS expression and NO production in Epo-treated cells. Furthermore, Epo pretreatment reduced nuclear translocation of NF-{kappa}B and inhibited phosphorylation of inhibitor of kappa B (I{kappa}B) in TNF-{alpha}-stimulated cardiac myoblasts. Thus, Epo protects cardiac myocyte progenitors or myoblasts against the cytotoxic effects of TNF-{alpha} by inhibiting NF-{kappa}B-mediated iNOS expression and NO production and by preventing caspase-3 activation.

  9. Doxorubicin Regulates Autophagy Signals via Accumulation of Cytosolic Ca2+ in Human Cardiac Progenitor Cells

    PubMed Central

    Park, Ji Hye; Choi, Sung Hyun; Kim, Hyungtae; Ji, Seung Taek; Jang, Woong Bi; Kim, Jae Ho; Baek, Sang Hong; Kwon, Sang Mo

    2016-01-01

    Doxorubicin (DOXO) is widely used to treat solid tumors. However, its clinical use is limited by side effects including serious cardiotoxicity due to cardiomyocyte damage. Resident cardiac progenitor cells (hCPCs) act as key regulators of homeostasis in myocardial cells. However, little is known about the function of hCPCs in DOXO-induced cardiotoxicity. In this study, we found that DOXO-mediated hCPC toxicity is closely related to calcium-related autophagy signaling and was significantly attenuated by blocking mTOR signaling in human hCPCs. DOXO induced hCPC apoptosis with reduction of SMP30 (regucalcin) and autophagosome marker LC3, as well as remarkable induction of the autophagy-related markers, Beclin-1, APG7, and P62/SQSTM1 and induction of calcium-related molecules, CaM (Calmodulin) and CaMKII (Calmodulin kinase II). The results of an LC3 puncta assay further indicated that DOXO reduced autophagosome formation via accumulation of cytosolic Ca2+. Additionally, DOXO significantly induced mTOR expression in hCPCs, and inhibition of mTOR signaling by rapamycin, a specific inhibitor, rescued DOXO-mediated autophagosome depletion in hCPCs with significant reduction of DOXO-mediated cytosolic Ca2+ accumulation in hCPCs, and restored SMP30 and mTOR expression. Thus, DOXO-mediated hCPC toxicity is linked to Ca2+-related autophagy signaling, and inhibition of mTOR signaling may provide a cardio-protective effect against DOXO-mediated hCPC toxicity. PMID:27735842

  10. Understanding a Period-Doubling Bifurcation in Cardiac Cells

    NASA Astrophysics Data System (ADS)

    Berger, Carolyn; Zhao, Xiaopeng; Schaeffer, David; Idriss, Salim; Gauthier, Daniel

    2008-03-01

    Bifurcations in the electrical response of cardiac tissue can destabilize spatio-temporal waves of electrochemical activity in the heart, leading to tachycardia or even fibrillation. Therefore, it is important to classify these bifurcations so that we can understand the mechanisms that cause instabilities in cardiac tissue. We have determined that the period-doubling bifurcation in paced myocardium is of the unfolded border-collision type. To understand how this new type of bifurcation manifest itself in cardiac tissue, we have also studied the role of calcium in inducing the bifurcation. We will discuss the nature of the unfolded border-collision bifurcation and present our results of dual voltage and calcium measurements in a frog ventricle preparation.

  11. Human embryonic stem cells vs human induced pluripotent stem cells for cardiac repair.

    PubMed

    Barad, Lili; Schick, Revital; Zeevi-Levin, Naama; Itskovitz-Eldor, Joseph; Binah, Ofer

    2014-11-01

    Human embryonic stem cells (hESCs) and human induced pluripotent stem cells (hiPSCs) have the capacity to differentiate into any specialized cell type, including cardiomyocytes. Therefore, hESC-derived and hiPSC-derived cardiomyocytes (hESC-CMs and hiPSC-CMs, respectively) offer great potential for cardiac regenerative medicine. Unlike some organs, the heart has a limited ability to regenerate, and dysfunction resulting from significant cardiomyocyte loss under pathophysiological conditions, such as myocardial infarction (MI), can lead to heart failure. Unfortunately, for patients with end-stage heart failure, heart transplantation remains the main alternative, and it is insufficient, mainly because of the limited availability of donor organs. Although left ventricular assist devices are progressively entering clinical practice as a bridge to transplantation and even as an optional therapy, cell replacement therapy presents a plausible alternative to donor organ transplantation. During the past decade, multiple candidate cells were proposed for cardiac regeneration, and their mechanisms of action in the myocardium have been explored. The purpose of this article is to critically review the comprehensive research involving the use of hESCs and hiPSCs in MI models and to discuss current controversies, unresolved issues, challenges, and future directions.

  12. Multicellular automaticity of cardiac cell monolayers: effects of density and spatial distribution of pacemaker cells

    NASA Astrophysics Data System (ADS)

    Elber Duverger, James; Boudreau-Béland, Jonathan; Le, Minh Duc; Comtois, Philippe

    2014-11-01

    Self-organization of pacemaker (PM) activity of interconnected elements is important to the general theory of reaction-diffusion systems as well as for applications such as PM activity in cardiac tissue to initiate beating of the heart. Monolayer cultures of neonatal rat ventricular myocytes (NRVMs) are often used as experimental models in studies on cardiac electrophysiology. These monolayers exhibit automaticity (spontaneous activation) of their electrical activity. At low plated density, cells usually show a heterogeneous population consisting of PM and quiescent excitable cells (QECs). It is therefore highly probable that monolayers of NRVMs consist of a heterogeneous network of the two cell types. However, the effects of density and spatial distribution of the PM cells on spontaneous activity of monolayers remain unknown. Thus, a simple stochastic pattern formation algorithm was implemented to distribute PM and QECs in a binary-like 2D network. A FitzHugh-Nagumo excitable medium was used to simulate electrical spontaneous and propagating activity. Simulations showed a clear nonlinear dependency of spontaneous activity (occurrence and amplitude of spontaneous period) on the spatial patterns of PM cells. In most simulations, the first initiation sites were found to be located near the substrate boundaries. Comparison with experimental data obtained from cardiomyocyte monolayers shows important similarities in the position of initiation site activity. However, limitations in the model that do not reflect the complex beat-to-beat variation found in experiments indicate the need for a more realistic cardiomyocyte representation.

  13. Dedifferentiated fat cells convert to cardiomyocyte phenotype and repair infarcted cardiac tissue in rats.

    PubMed

    Jumabay, Medet; Matsumoto, Taro; Yokoyama, Shin-ichiro; Kano, Koichiro; Kusumi, Yoshiaki; Masuko, Takayuki; Mitsumata, Masako; Saito, Satoshi; Hirayama, Atsushi; Mugishima, Hideo; Fukuda, Noboru

    2009-11-01

    Adipose tissue-derived stem cells have been demonstrated to differentiate into cardiomyocytes and vascular endothelial cells. Here we investigate whether mature adipocyte-derived dedifferentiated fat (DFAT) cells can differentiate to cardiomyocytes in vitro and in vivo by establishing DFAT cell lines via ceiling culture of mature adipocytes. DFAT cells were obtained by dedifferentiation of mature adipocytes from GFP-transgenic rats. We evaluated the differentiating ability of DFAT cells into cardiomyocytes by detection of the cardiac phenotype markers in immunocytochemical and RT-PCR analyses in vitro. We also examined effects of the transplantation of DFAT cells into the infarcted heart of rats on cardiomyocytes regeneration and angiogenesis. DFAT cells expressed cardiac phenotype markers when cocultured with cardiomyocytes and also when grown in MethoCult medium in the absence of cardiomyocytes, indicating that DFAT cells have the potential to differentiate to cardiomyocyte lineage. In a rat acute myocardial infarction model, transplanted DFAT cells were efficiently accumulated in infarcted myocardium and expressed cardiac sarcomeric actin at 8 weeks after the cell transplantation. The transplantation of DFAT cells significantly (p<0.05) increased capillary density in the infarcted area when compared with hearts from saline-injected control rats. We demonstrated that DFAT cells have the ability to differentiate to cardiomyocyte-like cells in vitro and in vivo. In addition, transplantation of DFAT cells led to neovascuralization in rats with myocardial infarction. We propose that DFAT cells represent a promising candidate cell source for cardiomyocyte regeneration in severe ischemic heart disease.

  14. Nicotinate-Curcumin Impedes Foam Cell Formation from THP-1 Cells through Restoring Autophagy Flux

    PubMed Central

    Gu, Hong-Feng; Li, Hai-Zhe; Tang, Ya-Ling; Tang, Xiao-Qing; Zheng, Xi-Long; Liao, Duan-Fang

    2016-01-01

    Our previous studies have indicated that a novel curcumin derivate nicotinate-curcumin (NC) has beneficial effects on the prevention of atherosclerosis, but the precise mechanisms are not fully understood. Given that autophagy regulates lipid metabolism, the present study was designed to investigate whether NC decreases foam cell formation through restoring autophagy flux in oxidized low-density lipoprotein (ox-LDL)-treated THP-1 cells. Our results showed that ox-LDL (100 μg/ml) was accumulated in THP-1 cells and impaired autophagy flux. Ox-LDL-induced impairment of autophagy was enhanced by treatment with the autophagy inhibitor chloroquine (CQ) and rescued by the autophagy inducer rapamycin. The aggregation of ox-LDL was increased by CQ, but decreased by rapamycin. In addition, colocalization of lipid droplets with LC3-II was remarkably reduced in ox-LDL group. In contrast, NC (10 μM) rescued the impaired autophagy flux by significantly increasing level of LC3-II, the number of autophagolysosomes, and the degradation of p62 in ox-LDL-treated THP-1 cells. Inhibition of the PI3K-Akt-mTOR signaling was required for NC-rescued autophagy flux. Notably, our results showed that NC remarkably promoted the colocalization of lipid droplets with autophagolysosomes, increased efflux of cholesterol, and reduced ox-LDL accumulation in THP-1 cells. However, treatment with 3-methyladenine (3-MA) or CQ reduced the protective effects of NC on lipid accumulation. Collectively, the findings suggest that NC decreases lipid accumulation in THP-1 cells through restoring autophagy flux, and further implicate that NC may be a potential therapeutic reagent to reverse atherosclerosis. PMID:27128486

  15. Electrical Stimulation Promotes Cardiac Differentiation of Human Induced Pluripotent Stem Cells

    PubMed Central

    Hernández, Damián; Millard, Rodney; Sivakumaran, Priyadharshini; Wong, Raymond C. B.; Crombie, Duncan E.; Hewitt, Alex W.; Liang, Helena; Hung, Sandy S. C.; Pébay, Alice; Shepherd, Robert K.; Dusting, Gregory J.; Lim, Shiang Y.

    2016-01-01

    Background. Human induced pluripotent stem cells (iPSCs) are an attractive source of cardiomyocytes for cardiac repair and regeneration. In this study, we aim to determine whether acute electrical stimulation of human iPSCs can promote their differentiation to cardiomyocytes. Methods. Human iPSCs were differentiated to cardiac cells by forming embryoid bodies (EBs) for 5 days. EBs were then subjected to brief electrical stimulation and plated down for 14 days. Results. In iPS(Foreskin)-2 cell line, brief electrical stimulation at 65 mV/mm or 200 mV/mm for 5 min significantly increased the percentage of beating EBs present by day 14 after plating. Acute electrical stimulation also significantly increased the cardiac gene expression of ACTC1, TNNT2, MYH7, and MYL7. However, the cardiogenic effect of electrical stimulation was not reproducible in another iPS cell line, CERA007c6. Beating EBs from control and electrically stimulated groups expressed various cardiac-specific transcription factors and contractile muscle markers. Beating EBs were also shown to cycle calcium and were responsive to the chronotropic agents, isoproterenol and carbamylcholine, in a concentration-dependent manner. Conclusions. Our results demonstrate that brief electrical stimulation can promote cardiac differentiation of human iPS cells. The cardiogenic effect of brief electrical stimulation is dependent on the cell line used. PMID:26788064

  16. Generation of Functional Human Cardiac Progenitor Cells by High-Efficiency Protein Transduction

    PubMed Central

    Li, Xiao-Hong; Li, Qianqian; Jiang, Lin; Deng, Chunyu; Liu, Zaiyi; Fu, Yongheng; Zhang, Mengzhen; Tan, Honghong; Feng, Yuliang; Shan, Zhixin

    2015-01-01

    The reprogramming of fibroblasts to induced pluripotent stem cells raises the possibility that somatic cells could be directly reprogrammed to cardiac progenitor cells (CPCs). The present study aimed to assess highly efficient protein-based approaches to reduce or eliminate the genetic manipulations to generate CPCs for cardiac regeneration therapy. A combination of QQ-reagent-modified Gata4, Hand2, Mef2c, and Tbx5 and three cytokines rapidly and efficiently reprogrammed human dermal fibroblasts (HDFs) into CPCs. This reprogramming process enriched trimethylated histone H3 lysine 4, monoacetylated histone H3 lysine 9, and Baf60c at the Nkx2.5 cardiac enhancer region by the chromatin immunoprecipitation quantitative polymerase chain reaction assay. Protein-induced CPCs transplanted into rat hearts after myocardial infarction improved cardiac function, and this was related to differentiation into cardiomyocyte-like cells. These findings demonstrate that the highly efficient protein-transduction method can directly reprogram HDFs into CPCs. This protein reprogramming strategy lays the foundation for future refinements both in vitro and in vivo and might provide a source of CPCs for regenerative approaches. Significance The findings from the present study have demonstrated an efficient protein-transduction method of directly reprogramming fibroblasts into cardiac progenitor cells. These results have great potential in cell-based therapy for cardiovascular diseases. PMID:26564862

  17. Strategies for heart regeneration: approaches ranging from induced pluripotent stem cells to direct cardiac reprogramming.

    PubMed

    Yamakawa, Hiroyuki; Ieda, Masaki

    2015-01-01

    Cardiovascular disease remains a leading cause of death for which current therapeutic regimens are limited. Following myocardial injury, endogenous cardiac fibroblasts, which account for more than half of the cells in the heart, proliferate and synthesize extracellular matrix, leading to fibrosis and heart failure. As terminally differentiated cardiomyocytes have little regenerative capacity following injury, development of cardiac regenerative therapy is highly desired. Embryonic stem (ES) and induced pluripotent stem (iPS) cells are promising tools for regenerative medicine; however, these stem cells demonstrate variable cardiac differentiation efficiency and tumorigenicity, which should be solved for clinical applications. Up until the last decade, it was an established theory that cardiomyocytes could only be produced from fibroblasts mediating through stem cells. However, in 2010, we reported for the first time a novel method of the direct reprogramming of fibroblasts into cardiomyocytes, demonstrating various reprogramming pathways exist. This review summarizes the latest trends in stem cell and regenerative research, touching upon iPS cells, partial reprogramming strategy, and direct cardiac reprogramming. Specifically, we examine the many recent advances in both in vitro and in vivo direct cardiac reprogramming, and explore the application of these methods to cardiovascular regenerative medicine.

  18. Cardiac Non-myocyte Cells Show Enhanced Pharmacological Function Suggestive of Contractile Maturity in Stem Cell Derived Cardiomyocyte Microtissues

    PubMed Central

    Ravenscroft, Stephanie M.; Pointon, Amy; Williams, Awel W.; Cross, Michael J.; Sidaway, James E.

    2016-01-01

    The immature phenotype of stem cell derived cardiomyocytes is a significant barrier to their use in translational medicine and pre-clinical in vitro drug toxicity and pharmacological analysis. Here we have assessed the contribution of non-myocyte cells on the contractile function of co-cultured human embryonic stem cell derived cardiomyocytes (hESC-CMs) in spheroid microtissue format. Microtissues were formed using a scaffold free 96-well cell suspension method from hESC-CM cultured alone (CM microtissues) or in combination with human primary cardiac microvascular endothelial cells and cardiac fibroblasts (CMEF microtissues). Contractility was characterized with fluorescence and video-based edge detection. CMEF microtissues displayed greater Ca2+ transient amplitudes, enhanced spontaneous contraction rate and remarkably enhanced contractile function in response to both positive and negative inotropic drugs, suggesting a more mature contractile phenotype than CM microtissues. In addition, for several drugs the enhanced contractile response was not apparent when endothelial cell or fibroblasts from a non-cardiac tissue were used as the ancillary cells. Further evidence of maturity for CMEF microtissues was shown with increased expression of genes that encode proteins critical in cardiac Ca2+ handling (S100A1), sarcomere assembly (telethonin/TCAP) and β-adrenergic receptor signalling. Our data shows that compared with single cell-type cardiomyocyte in vitro models, CMEF microtissues are superior at predicting the inotropic effects of drugs, demonstrating the critical contribution of cardiac non-myocyte cells in mediating functional cardiotoxicity. PMID:27125969

  19. Hypoxia Enhances Differentiation of Hair Follicle-Associated-Pluripotent (HAP) Stem Cells to Cardiac-Muscle Cells.

    PubMed

    Shirai, Kyoumi; Hamada, Yuko; Arakawa, Nobuko; Yamazaki, Aiko; Tohgi, Natsuko; Aki, Ryoichi; Mii, Sumiyuki; Hoffman, Robert M; Amoh, Yasuyuki

    2017-03-01

    We have previously demonstrated that the neural stem-cell marker nestin is expressed in hair-follicle stem cells located in the bulge area which are termed hair-follicle-associated pluripotent (HAP) stem cells. HAP stem cells from mouse and human could form spheres in culture, termed hair spheres, which are keratin 15-negative and nestin-positive and could differentiate to neurons, glia, keratinocytes, smooth muscle cells, and melanocytes in vitro. Subsequently, we demonstrated that nestin-expressing stem cells could effect nerve and spinal cord regeneration in mouse models. Recently, we demonstrated that HAP stem cells differentiated to beating cardiac muscle cells. We recently observed that isoproterenol directs HAP stem cells to differentiate to cardiac-muscle cells in large numbers in culture compared to HAP stem cells not supplemented with isoproterenol. The addition of activin A, bone morphogenetic protein 4, and basic fibroblast growth factor, along with isoproternal, induced the cardiac muscle cells to form tissue sheets of beating heart muscle cells. In the present study, we report that, under hypoxic conditions, HAP stem cells differentiated to troponin-positive cardiac-muscle cells at a higher rate that under normoxic conditions. Hypoxia did not influence the differentiation to other cell types. For future use of HAP stem cells for cardiac muscle regeneration, hypoxia should enhance the rate of differentiation thereby providing patients more opportunities to use their own HAP stem cells which are easily accessible, for this purpose. J. Cell. Biochem. 118: 554-558, 2017. © 2016 Wiley Periodicals, Inc.

  20. Evidence for Transfer of Membranes from Mesenchymal Stem Cells to HL-1 Cardiac Cells.

    PubMed

    Boomsma, Robert A; Geenen, David L

    2014-01-01

    This study examined the interaction of mouse bone marrow mesenchymal stem cells (MSC) with cardiac HL-1 cells during coculture by fluorescent dye labeling and then flow cytometry. MSC were layered onto confluent HL-1 cell cultures in a 1 : 4 ratio. MSC gained gap junction permeant calcein from HL-1 cells after 4 hours which was partially reduced by oleamide. After 20 hours, 99% MSC gained calcein, unaffected by oleamide. Double-labeling HL-1 cells with calcein and the membrane dye DiO resulted in transfer of both calcein and DiO to MSC. When HL-1 cells were labeled with calcein and MSC with DiO, MSC gained calcein while HL-1 cells gained DiO. Very little fusion was observed since more than 90% Sca-1 positive MSC gained DiO from HL-1 cells while less than 9% gained gap junction impermeant CMFDA after 20 hours with no Sca-1 transfer to HL-1 cells. Time dependent transfer of membrane DiD was observed from HL-1 cells to MSC (100%) and vice versa (50%) after 20 hours with more limited transfer of CMFDA. These results demonstrate that MSC and HL-1 cells exchange membrane components which may account for some of the beneficial effect of MSC in the heart after myocardial infarction.

  1. Cardiac stem cell niche, MMP9, and culture and differentiation of embryonic stem cells.

    PubMed

    Mishra, Paras Kumar; Kuypers, Nicholas John; Singh, Shree Ram; Leiberh, Noel Diaz; Chavali, Vishalakshi; Tyagi, Suresh C

    2013-01-01

    Embryonic stem cells (ESC) are totipotent, self-renewing, and clonogenic, having potential to differentiate into a wide variety of cell types. Due to regenerative capability, it has tremendous potential for treating myocardial infarction (death of myocardial tissue) and type 1 diabetes (death of pancreatic beta cells). Understanding the components regulating ESC differentiation is the key to unlock the regenerative potential of ESC-based therapies. Both the stiffness of extracellular matrix (ECM) and surrounding niche/microenvironment play pivotal roles in ESC differentiation. Matrix metalloproteinase-9 (MMP9) induces fibrosis that causes stiffness of the ECM and impairs differentiation of cardiac stem cells into cardiomyocytes. Here, we describe the method of ESC culture and differentiation, and the expression of MMP9 and its inhibitor, tissue inhibitor of metalloproteinase-4 (TIMP4) in differentiating ESC.

  2. Sickle cell anaemia and the consequences on the anaesthetic management of cardiac surgery.

    PubMed

    Mennes, I; Van de Velde, M; Missant, C

    2012-01-01

    A review of the available literature on genetics and pathophysiology of Sickle Cell Anaemia was performed with special emphasis on the intraoperative management during cardiac surgery. Hypoxia, acidosis and hypothermia have been identified as independent sickling provoking factors. Although no official guidelines on transfusion for Sickle Cell patients have been published, useful directives on preoperative transfusion could be derived from available data. Additionally, we bundled and reviewed the published expertise in the management of cardiopulmonary bypass and the necessity of hypothermia during cardiac surgery in Sickle Cell patients. Our conclusion is that the available data in case reports and case series on cardiac surgery in case of Sickle Cell Anaemia suggest a necessary preoperative or on bypass blood transfusion to guarantee an uncomplicated course of cardiopulmonary bypass and hypothermia.

  3. Polymeric scaffold aided stem cell therapeutics for cardiac muscle repair and regeneration.

    PubMed

    Lakshmanan, Rajesh; Krishnan, Uma Maheswari; Sethuraman, Swaminathan

    2013-09-01

    The constantly expanding repository of novel polymers and stem cells has opened up new vistas in the field of cardiac tissue engineering. Successful regeneration of the complex cardiac tissue mainly centres on the appropriate scaffold material with topographical features that mimic the native environment. The integration of stem cells on these scaffolds is expected to enhance the regeneration potential. This review elaborates on the interplay of these vital factors in achieving the functional cardiac tissue. The recent advances in polymers, nanocomposites, and stem cells from different sources are highlighted. Special emphasis is laid on the clinical trials involving stem cells and the state-of-the-art materials to obtain a balanced perspective on the translational potential of this strategy.

  4. Human Thymus Mesenchymal Stromal Cells Augment Force Production in Self-Organized Cardiac Tissue

    PubMed Central

    Sondergaard, Claus S.; Hodonsky, Chani J.; Khait, Luda; Shaw, John; Sarkar, Bedabrata; Birla, Ravi; Bove, Edward; Nolta, Jan; Si, Ming-Sing

    2011-01-01

    Background Mesenchymal stromal cells have been recently isolated from thymus gland tissue discarded after surgical procedures. The role of this novel cell type in heart regeneration has yet to be defined. The purpose of this study was to evaluate the therapeutic potential of human thymus-derived mesenchymal stromal cells using self-organized cardiac tissue as an in vitro platform for quantitative assessment. Methods Mesenchymal stromal cells were isolated from discarded thymus tissue from neonates undergoing heart surgery and were incubated in differentiation media to demonstrate multipotency. Neonatal rat cardiomyocytes self-organized into cardiac tissue fibers in a custom culture dish either alone or in combination with varying numbers of mesenchymal stromal cells. A transducer measured force generated by spontaneously contracting self-organized cardiac tissue fibers. Work and power outputs were calculated from force tracings. Immunofluorescence was performed to determine the fate of the thymus-derived mesenchymal stromal cells. Results Mesenchymal stromal cells were successfully isolated from discarded thymus tissue. After incubation in differentiation media, mesenchymal stromal cells attained the expected phenotypes. Although mesenchymal stromal cells did not differentiate into mature cardiomyocytes, addition of these cells increased the rate of fiber formation, force production, and work and power outputs. Self-organized cardiac tissue containing mesenchymal stromal cells acquired a defined microscopic architecture. Conclusions Discarded thymus tissue contains mesenchymal stromal cells, which can augment force production and work and power outputs of self-organized cardiac tissue fibers by several-fold. These findings indicate the potential utility of mesenchymal stromal cells in treating heart failure. PMID:20732499

  5. Isolation, characterization and cardiac differentiation of human thymus tissue derived mesenchymal stromal cells.

    PubMed

    Lin, Ze Bang; Qian, Bo; Yang, Yu Zhong; Zhou, Kai; Sun, Jian; Mo, Xu Ming; Wu, Kai Hong

    2015-07-01

    Mesenchymal stromal cells (MSCs) are promising candidate donor cells for replacement of cardiomyocyte loss during ischemia and in vitro generation of myocardial tissue. We have successfully isolated MSCs from the discarded neonatal thymus gland during cardiac surgery. The thymus MSCs were characterized by cell-surface antigen expression. These cells have high ability for proliferation and are able to differentiate into osteoblasts and adipocytes in vitro. For cardiac differentiation, the cells were divided into 3 groups: untreated control; 5-azacytidine group and sequential exposure to 5-azacytidine, bone morphogenetic protein 4, and basic fibroblast growth factor. Thymus MSCs showed a fibrolast-like morphology and some differentiated cells increased in size, formed a ball-like appearance over time and spontaneously contracting cells were observed in sequential exposure group. Immunostaining studies, cardiac specific genes/protein expression confirmed the cardiomyocyte phenotype of the differentiated cells. These results demonstrate that thymus MSCs can be a promising cellular source for cardiac cell therapy and tissue engineering.

  6. Cardiac progenitors derived from reprogrammed mesenchymal stem cells contribute to angiomyogenic repair of the infarcted heart.

    PubMed

    Buccini, Stephanie; Haider, Khawaja Husnain; Ahmed, Rafeeq P H; Jiang, Shujia; Ashraf, Muhammad

    2012-11-01

    The strategy to reprogram somatic stem cells to pluripotency status has provided an alternative source of surrogate ES cells (ESC). We report efficient reprogramming of multipotent bone marrow (BM) mesenchymal stem cells (MSC) to pluripotent status and the resultant MSC derived iPS cells (MiPS) and their derived progenitors effectively repaired the infarcted heart. MSC from young, male, Oct4-GFP transgenic mice were reprogrammed by retroviral transduction with Oct4, Sox2, Klf4, and c-Myc stemness factors. MiPS thus generated displayed characteristics of mouse ESC including morphology, surface antigens, gene and miR expression profiles. MiPS also formed spontaneously beating cardiac progenitors which expressed cardiac specific transcription factors and protein markers including Gata4, Mef2c, Nkx2.5, myosin heavy chain, troponin-I, and troponin-T, and showed ultra structural characteristics typical of cardiomyocytes. Intramyocardial delivery of MiPS (group-2) and their derivative cardiac-like cells (MiPS-CP; group-3) in a mouse model of acute myocardial infarction showed extensive survival and engraftment at 4 weeks with resultant attenuation of infarct size (p < 0.001 vs. DMEM injected control; n = 4). Engraftment of MiPS-CP was without cardiac tumorigenesis as compared to 21 % in MiPS transplanted animals. Furthermore, angiogenesis was improved in groups-2 and 3 (p < 0.001 vs. control). Transthoracic echocardiography revealed significantly preserved indices of cardiac contractility (ejection fraction p < 0.001 and fractional shortening p < 0.001 vs. control; n = 7). MSC were successfully reprogrammed into MiPS that displayed ESC-like characteristics and differentiated into spontaneously beating cardiomyocytes. Cardiac progenitors derived from MiPS repopulated the infarcted heart without tumorigenesis and improved global cardiac function.

  7. Method for restoration of normal phenotype in cancer cells

    DOEpatents

    Bissell, Mina J.; Weaver, Valerie M.

    2000-01-01

    A method for reversing expression of malignant phenotype in cancer cells is described. The method comprises applying .beta..sub.1 integrin function-blocking antibody to the cells. The method can be used to assess the progress of cancer therapy. Human breast epithelial cells were shown to be particularly responsive.

  8. Rejuvenating stem cells to restore muscle regeneration in aging

    PubMed Central

    Bengal, Eyal; Perdiguero, Eusebio; Serrano, Antonio L.; Muñoz-Cánoves, Pura

    2017-01-01

    Adult muscle stem cells, originally called satellite cells, are essential for muscle repair and regeneration throughout life. Besides a gradual loss of mass and function, muscle aging is characterized by a decline in the repair capacity, which blunts muscle recovery after injury in elderly individuals. A major effort has been dedicated in recent years to deciphering the causes of satellite cell dysfunction in aging animals, with the ultimate goal of rejuvenating old satellite cells and improving muscle function in elderly people. This review focuses on the recently identified network of cell-intrinsic and -extrinsic factors and processes contributing to the decline of satellite cells in old animals. Some studies suggest that aging-related satellite-cell decay is mostly caused by age-associated extrinsic environmental changes that could be reversed by a “youthful environment”. Others propose a central role for cell-intrinsic mechanisms, some of which are not reversed by environmental changes. We believe that these proposals, far from being antagonistic, are complementary and that both extrinsic and intrinsic factors contribute to muscle stem cell dysfunction during aging-related regenerative decline. The low regenerative potential of old satellite cells may reflect the accumulation of deleterious changes during the life of the cell; some of these changes may be inherent (intrinsic) while others result from the systemic and local environment (extrinsic). The present challenge is to rejuvenate aged satellite cells that have undergone reversible changes to provide a possible approach to improving muscle repair in the elderly. PMID:28163911

  9. Enhancement of early cardiac differentiation of dedifferentiated fat cells by dimethyloxalylglycine via notch signaling pathway

    PubMed Central

    Li, Fuhai; Li, Zongzhuang; Jiang, Zhi; Tian, Ye; Wang, Zhi; Yi, Wei; Zhang, Chenyun

    2016-01-01

    Background: Hypoxia has been reported to possess the ability to induce mature lipid-filled adipocytes to differentiate into fibroblast-like multipotent dedifferentiated fat (DFAT) cells and stem cells such as iPSCs (interstitial pluripotent stem cells) and ESCs (embryonic stem cells) and then to differentiate into cardiomyocytes. However, the effect of hypoxia on cardiac differentiation of DFAT cells and its underlying molecular mechanism remains to be investigated. Objective: To investigate the role of hypoxia in early cardiac differentiation of DFAT cells and the underlying molecular mechanism. Methods: DFAT cells were prepared from 4 to 6 week-age mice and cultured under hypoxic conditions by adding Prolyl hydroxylase inhibitor and dimethyloxalylglycine (DMOG) into the culture media. To inhibit or block Notch signaling, γ-secretase inhibitor-II (GSI-II) and Notch1 siRNA (si-Notch1) were used. DFAT cell viability was detected using MTT assay. qRT-PCR, immunofluorescence microscopy and western blotting were used to evaluate the cardiac differentiation of DFAT cells and co-immunoprecipitation was used to study the interaction between HIF-1α and Notch signaling. Results: 0.6-mM DMOG failed to affect the viability of DFAT cells, but stimulated the cells to express early cardiac transcription factors including Islet1, Nkx2.5 and Gata4 in a time-dependent manner and increase the number of cTnT+ cardiomyocytes (detected at the 28th day after stimulation). It was also demonstrated that DMOG was involved in HIF-1α and Notch signaling as well as HIF-1α-NICD complex formation. Conclusion: Hypoxia enhanced early cardiac differentiation of DFAT cells through HIF-1α and Notch signaling pathway. PMID:27904680

  10. Enhancement of early cardiac differentiation of dedifferentiated fat cells by dimethyloxalylglycine via notch signaling pathway.

    PubMed

    Li, Fuhai; Li, Zongzhuang; Jiang, Zhi; Tian, Ye; Wang, Zhi; Yi, Wei; Zhang, Chenyun

    2016-01-01

    Background: Hypoxia has been reported to possess the ability to induce mature lipid-filled adipocytes to differentiate into fibroblast-like multipotent dedifferentiated fat (DFAT) cells and stem cells such as iPSCs (interstitial pluripotent stem cells) and ESCs (embryonic stem cells) and then to differentiate into cardiomyocytes. However, the effect of hypoxia on cardiac differentiation of DFAT cells and its underlying molecular mechanism remains to be investigated. Objective: To investigate the role of hypoxia in early cardiac differentiation of DFAT cells and the underlying molecular mechanism. Methods: DFAT cells were prepared from 4 to 6 week-age mice and cultured under hypoxic conditions by adding Prolyl hydroxylase inhibitor and dimethyloxalylglycine (DMOG) into the culture media. To inhibit or block Notch signaling, γ-secretase inhibitor-II (GSI-II) and Notch1 siRNA (si-Notch1) were used. DFAT cell viability was detected using MTT assay. qRT-PCR, immunofluorescence microscopy and western blotting were used to evaluate the cardiac differentiation of DFAT cells and co-immunoprecipitation was used to study the interaction between HIF-1α and Notch signaling. Results: 0.6-mM DMOG failed to affect the viability of DFAT cells, but stimulated the cells to express early cardiac transcription factors including Islet1, Nkx2.5 and Gata4 in a time-dependent manner and increase the number of cTnT(+) cardiomyocytes (detected at the 28(th) day after stimulation). It was also demonstrated that DMOG was involved in HIF-1α and Notch signaling as well as HIF-1α-NICD complex formation. Conclusion: Hypoxia enhanced early cardiac differentiation of DFAT cells through HIF-1α and Notch signaling pathway.

  11. Cardiac differentiation potential of human induced pluripotent stem cells in a 3D self-assembling peptide scaffold.

    PubMed

    Puig-Sanvicens, Veronica A C; Semino, Carlos E; Zur Nieden, Nicole I

    2015-01-01

    In the past decade, various strategies for cardiac reparative medicine involving stem cells from multiple sources have been investigated. However, the intra-cardiac implantation of cells with contractile ability may seriously disrupt the cardiac syncytium and de-synchronize cardiac rhythm. For this reason, bioactive cardiac implants, consisting of stem cells embedded in biomaterials that act like band aids, have been exploited to repair the cardiac wall after myocardial infarction. For such bioactive implants to function properly after transplantation, the choice of biomaterial is equally important as the selection of the stem cell source. While adult stem cells have shown promising results, they have various disadvantages including low proliferative potential in vitro, which make their successful usage in human transplants difficult. As a first step towards the development of a bioactive cardiac patch, we investigate here the cardiac differentiation properties of human induced pluripotent stem cells (hiPSCs) when cultured with and without ascorbic acid (AA) and when embedded in RAD16-I, a biomaterial commonly used to develop cardiac implants. In adherent cultures and in the absence of RAD16-I, AA promotes the cardiac differentiation of hiPSCs by enhancing the expression of specific cardiac genes and proteins and by increasing the number of contracting clusters. In turn, embedding in peptide hydrogel based on RAD16-I interferes with the normal cardiac differentiation progression. Embedded hiPSCs up-regulate genes associated with early cardiogenesis by up to 105 times independently of the presence of AA. However, neither connexin 43 nor troponin I proteins, which are related with mature cardiomyocytes, were detected and no contraction was noted in the constructs. Future experiments will need to focus on characterizing the mature cardiac phenotype of these cells when implanted into infarcted myocardia and assess their regenerative potential in vivo.

  12. Influence of aging on the activity of mice Sca-1+CD31− cardiac stem cells

    PubMed Central

    Pu, Shiming; Qin, Liu; Li, Yun; Zhou, Zuping

    2017-01-01

    Therapeutic application of cardiac resident stem/progenitor cells (CSC/CPCs) is limited due to decline of their regenerative potential with donor age. A variety of studies have shown that the cardiac aging was the problem of the stem cells, but little is known about the impact of age on the subgroups CSC/CPCs, the relationship between subgroups CSC/CPCs ageing and age-related dysfunction. Here, we studied Sca-1+CD31− subgroups of CSCs from younger(2~3months) and older(22~24months) age mice, biological differentiation was realized using specific mediums for 14 days to induce cardiomyocyte, smooth muscle cells or endothelial cells and immunostain analysis of differentiated cell resulting were done. Proliferation and cell cycle were measured by flow cytometry assay, then used microarray to dissect variability from younger and older mice. Although the number of CSCs was higher in older mice, the advanced age significantly reduced the differentiation ability into cardiac cell lineages and the proliferation ability. Transcriptional changes in Sca-1+CD31− subgroups of CSCs during aging are related to Vitamin B6 metabolism, circadian rhythm, Tyrosine metabolism, Complement and coagulation cascades. Taking together these results indicate that Cardiac resident stem/progenitor cells have significant differences in their proliferative, pluripotency and gene profiles and those differences are age depending. PMID:27980224

  13. Cardiac cell proliferation is not necessary for exercise-induced cardiac growth but required for its protection against ischaemia/reperfusion injury.

    PubMed

    Bei, Yihua; Fu, Siyi; Chen, Xiangming; Chen, Mei; Zhou, Qiulian; Yu, Pujiao; Yao, Jianhua; Wang, Hongbao; Che, Lin; Xu, Jiahong; Xiao, Junjie

    2017-03-17

    The adult heart retains a limited ability to regenerate in response to injury. Although exercise can reduce cardiac ischaemia/reperfusion (I/R) injury, the relative contribution of cardiac cell proliferation including newly formed cardiomyocytes remains unclear. A 4-week swimming murine model was utilized to induce cardiac physiological growth. Simultaneously, the antineoplastic agent 5-fluorouracil (5-FU), which acts during the S phase of the cell cycle, was given to mice via intraperitoneal injections. Using EdU and Ki-67 immunolabelling, we showed that exercise-induced cardiac cell proliferation was blunted by 5-FU. In addition, the growth of heart in size and weight upon exercise was unaltered, probably due to the fact that exercise-induced cardiomyocyte hypertrophy was not influenced by 5-FU as demonstrated by wheat germ agglutinin staining. Meanwhile, the markers for pathological hypertrophy, including ANP and BNP, were not changed by either exercise or 5-FU, indicating that physiological growth still developed in the presence of 5-FU. Furthermore, we showed that CITED4, a key regulator for cardiomyocyte proliferation, was blocked by 5-FU. Meanwhile, C/EBPβ, a transcription factor responsible for both cellular proliferation and hypertrophy, was not altered by treatment with 5-FU. Importantly, the effects of exercise in reducing cardiac I/R injury could be abolished when cardiac cell proliferation was attenuated in mice treated with 5-FU. In conclusion, cardiac cell proliferation is not necessary for exercise-induced cardiac physiological growth, but it is required for exercise-associated protection against I/R injury.

  14. Regulation of Cardiac Remodeling by Cardiac Na(+)/K(+)-ATPase Isoforms.

    PubMed

    Liu, Lijun; Wu, Jian; Kennedy, David J

    2016-01-01

    Cardiac remodeling occurs after cardiac pressure/volume overload or myocardial injury during the development of heart failure and is a determinant of heart failure. Preventing or reversing remodeling is a goal of heart failure therapy. Human cardiomyocyte Na(+)/K(+)-ATPase has multiple α isoforms (1-3). The expression of the α subunit of the Na(+)/K(+)-ATPase is often altered in hypertrophic and failing hearts. The mechanisms are unclear. There are limited data from human cardiomyocytes. Abundant evidences from rodents show that Na(+)/K(+)-ATPase regulates cardiac contractility, cell signaling, hypertrophy and fibrosis. The α1 isoform of the Na(+)/K(+)-ATPase is the ubiquitous isoform and possesses both pumping and signaling functions. The α2 isoform of the Na(+)/K(+)-ATPase regulates intracellular Ca(2+) signaling, contractility and pathological hypertrophy. The α3 isoform of the Na(+)/K(+)-ATPase may also be a target for cardiac hypertrophy. Restoration of cardiac Na(+)/K(+)-ATPase expression may be an effective approach for prevention of cardiac remodeling. In this article, we will overview: (1) the distribution and function of isoform specific Na(+)/K(+)-ATPase in the cardiomyocytes. (2) the role of cardiac Na(+)/K(+)-ATPase in the regulation of cell signaling, contractility, cardiac hypertrophy and fibrosis in vitro and in vivo. Selective targeting of cardiac Na(+)/K(+)-ATPase isoform may offer a new target for the prevention of cardiac remodeling.

  15. Regulation of Cardiac Remodeling by Cardiac Na+/K+-ATPase Isoforms

    PubMed Central

    Liu, Lijun; Wu, Jian; Kennedy, David J.

    2016-01-01

    Cardiac remodeling occurs after cardiac pressure/volume overload or myocardial injury during the development of heart failure and is a determinant of heart failure. Preventing or reversing remodeling is a goal of heart failure therapy. Human cardiomyocyte Na+/K+-ATPase has multiple α isoforms (1–3). The expression of the α subunit of the Na+/K+-ATPase is often altered in hypertrophic and failing hearts. The mechanisms are unclear. There are limited data from human cardiomyocytes. Abundant evidences from rodents show that Na+/K+-ATPase regulates cardiac contractility, cell signaling, hypertrophy and fibrosis. The α1 isoform of the Na+/K+-ATPase is the ubiquitous isoform and possesses both pumping and signaling functions. The α2 isoform of the Na+/K+-ATPase regulates intracellular Ca2+ signaling, contractility and pathological hypertrophy. The α3 isoform of the Na+/K+-ATPase may also be a target for cardiac hypertrophy. Restoration of cardiac Na+/K+-ATPase expression may be an effective approach for prevention of cardiac remodeling. In this article, we will overview: (1) the distribution and function of isoform specific Na+/K+-ATPase in the cardiomyocytes. (2) the role of cardiac Na+/K+-ATPase in the regulation of cell signaling, contractility, cardiac hypertrophy and fibrosis in vitro and in vivo. Selective targeting of cardiac Na+/K+-ATPase isoform may offer a new target for the prevention of cardiac remodeling. PMID:27667975

  16. Protective effect of creatine against inhibition by methylglyoxal of mitochondrial respiration of cardiac cells.

    PubMed

    Roy, Soumya Sinha; Biswas, Swati; Ray, Manju; Ray, Subhankar

    2003-06-01

    Previous publications from our laboratory have shown that methylglyoxal inhibits mitochondrial respiration of malignant and cardiac cells, but it has no effect on mitochondrial respiration of other normal cells [Biswas, Ray, Misra, Dutta and Ray (1997) Biochem. J. 323, 343-348; Ray, Biswas and Ray (1997) Mol. Cell. Biochem. 171, 95-103]. However, this inhibitory effect of methylglyoxal is not significant in cardiac tissue slices. Moreover, post-mitochondrial supernatant (PMS) of cardiac cells could almost completely protect the mitochondrial respiration against the inhibitory effect of methylglyoxal. A systematic search indicated that creatine present in cardiac cells is responsible for this protective effect. Glutathione has also some protective effect. However, creatine phosphate, creatinine, urea, glutathione disulphide and beta-mercaptoethanol have no protective effect. The inhibitory and protective effects of methylglyoxal and creatine respectively on cardiac mitochondrial respiration were studied with various concentrations of both methylglyoxal and creatine. Interestingly, neither creatine nor glutathione have any protective effect on the inhibition by methylglyoxal on the mitochondrial respiration of Ehrlich ascites carcinoma cells. The creatine and glutathione contents of several PMS, which were tested for the possible protective effect, were measured. The activities of two important enzymes, namely glyoxalase I and creatine kinase, which act upon glutathione plus methylglyoxal and creatine respectively, were also measured in different PMS. Whether mitochondrial creatine kinase had any role in the protective effect of creatine had also been investigated using 1-fluoro-2,4-dinitrobenzene, an inhibitor of creatine kinase. The differential effect of creatine on mitochondria of cardiac and malignant cells has been discussed with reference to the therapeutic potential of methylglyoxal.

  17. Targeting cardiac mast cells: pharmacological modulation of the local renin-angiotensin system.

    PubMed

    Reid, Alicia C; Brazin, Jacqueline A; Morrey, Christopher; Silver, Randi B; Levi, Roberto

    2011-11-01

    Enhanced production of angiotensin II and excessive release of norepinephrine in the ischemic heart are major causes of arrhythmias and sudden cardiac death. Mast cell-dependent mechanisms are pivotal in the local formation of angiotensin II and modulation of norepinephrine release in cardiac pathophysiology. Cardiac mast cells increase in number in myocardial ischemia and are located in close proximity to sympathetic neurons expressing angiotensin AT1- and histamine H3-receptors. Once activated, cardiac mast cells release a host of potent pro-inflammatory and pro-fibrotic cytokines, chemokines, preformed mediators (e.g., histamine) and proteases (e.g., renin). In myocardial ischemia, angiotensin II (formed locally from mast cell-derived renin) and histamine (also released from local mast cells) respectively activate AT1- and H3-receptors on sympathetic nerve endings. Stimulation of angiotensin AT1-receptors is arrhythmogenic whereas H3-receptor activation is cardioprotective. It is likely that in ischemia/reperfusion the balance may be tipped toward the deleterious effects of mast cell renin, as demonstrated in mast cell-deficient mice, lacking mast cell renin and histamine in the heart. In these mice, no ventricular fibrillation occurs at reperfusion following ischemia, as opposed to wild-type hearts which all fibrillate. Preventing mast cell degranulation in the heart and inhibiting the activation of a local renin-angiotensin system, hence abolishing its detrimental effects on cardiac rhythmicity, appears to be more significant than the loss of histamine-induced cardioprotection. This suggests that therapeutic targets in the treatment of myocardial ischemia, and potentially congestive heart failure and hypertension, should include prevention of mast cell degranulation, mast cell renin inhibition, local ACE inhibition, ANG II antagonism and H3-receptor activation.

  18. Mesenchymal stem cell-loaded cardiac patch promotes epicardial activation and repair of the infarcted myocardium.

    PubMed

    Wang, Qiang-Li; Wang, Hai-Jie; Li, Zhi-Hua; Wang, Yong-Li; Wu, Xue-Ping; Tan, Yu-Zhen

    2017-02-28

    Cardiac patch is considered a promising strategy for enhancing stem cell therapy of myocardial infarction (MI). However, the underlying mechanisms for cardiac patch repairing infarcted myocardium remain unclear. In this study, we investigated the mechanisms of PCL/gelatin patch loaded with MSCs on activating endogenous cardiac repair. PCL/gelatin patch was fabricated by electrospun. The patch enhanced the survival of the seeded MSCs and their HIF-1α, Tβ4, VEGF and SDF-1 expression and decreased CXCL14 expression in hypoxic and serum-deprived conditions. In murine MI models, the survival and distribution of the engrafted MSCs and the activation of the epicardium were examined, respectively. At 4 weeks after transplantation of the cell patch, the cardiac functions were significantly improved. The engrafted MSCs migrated across the epicardium and into the myocardium. Tendency of HIF-1α, Tβ4, VEGF, SDF-1 and CXCL14 expression in the infarcted myocardium was similar with expression in vitro. The epicardium was activated and epicardial-derived cells (EPDCs) migrated into deep tissue. The EPDCs differentiated into endothelial cells and smooth muscle cells, and some of EPDCs showed to have differentiated into cardiomyocytes. Density of blood and lymphatic capillaries increased significantly. More c-kit(+) cells were recruited into the infarcted myocardium after transplantation of the cell patch. The results suggest that epicardial transplantation of the cell patch promotes repair of the infarcted myocardium and improves cardiac functions by enhancing the survival of the transplanted cells, accelerating locality paracrine, and then activating the epicardium and recruiting endogenous c-kit(+) cells. Epicardial transplantation of the cell patch may be applied as a novel effective MI therapy.

  19. Identification of drugs that restore primary cilium expression in cancer cells

    PubMed Central

    Khan, Niamat Ali; Willemarck, Nicolas; Talebi, Ali; Marchand, Arnaud; Binda, Maria Mercedes; Dehairs, Jonas; Rueda-Rincon, Natalia; Daniels, Veerle W.; Bagadi, Muralidhararao; Raj, Deepak Balaji Thimiri Govinda; Vanderhoydonc, Frank; Munck, Sebastian; Chaltin, Patrick; Swinnen, Johannes V.

    2016-01-01

    The development of cancer is often accompanied by a loss of the primary cilium, a microtubule-based cellular protrusion that functions as a cellular antenna and that puts a break on cell proliferation. Hence, restoration of the primary cilium in cancer cells may represent a novel promising approach to attenuate tumor growth. Using a high content analysis-based approach we screened a library of clinically evaluated compounds and marketed drugs for their ability to restore primary cilium expression in pancreatic ductal cancer cells. A diverse set of 118 compounds stimulating cilium expression was identified. These included glucocorticoids, fibrates and other nuclear receptor modulators, neurotransmitter regulators, ion channel modulators, tyrosine kinase inhibitors, DNA gyrase/topoisomerase inhibitors, antibacterial compounds, protein inhibitors, microtubule modulators, and COX inhibitors. Certain compounds also dramatically affected the length of the cilium. For a selection of compounds (Clofibrate, Gefitinib, Sirolimus, Imexon and Dexamethasone) their ability to restore ciliogenesis was confirmed in a panel of human cancer cell line models representing different cancer types (pancreas, lung, kidney, breast). Most compounds attenuated cell proliferation, at least in part through induction of the primary cilium, as demonstrated by cilium removal using chloral hydrate. These findings reveal that several commonly used drugs restore ciliogenesis in cancer cells, and warrant further investigation of their antineoplastic properties. PMID:26862738

  20. Cardiac Regenerative Medicine: The Potential of a New Generation of Stem Cells.

    PubMed

    Cambria, Elena; Steiger, Julia; Günter, Julia; Bopp, Annina; Wolint, Petra; Hoerstrup, Simon P; Emmert, Maximilian Y

    2016-07-01

    Cardiac stem cell therapy holds great potential to prompt myocardial regeneration in patients with ischemic heart disease. The selection of the most suitable cell type is pivotal for its successful application. Various cell types, including crude bone marrow mononuclear cells, skeletal myoblast, and hematopoietic and endothelial progenitors, have already advanced into the clinical arena based on promising results from different experimental and preclinical studies. However, most of these so-called first-generation cell types have failed to fully emulate the promising preclinical data in clinical trials, resulting in heterogeneous outcomes and a critical lack of translation. Therefore, different next-generation cell types are currently under investigation for the treatment of the diseased myocardium. This review article provides an overview of current stem cell therapy concepts, including the application of cardiac stem (CSCs) and progenitor cells (CPCs) and lineage commitment via guided cardiopoiesis from multipotent cells such as mesenchymal stem cells (MSCs) or pluripotent cells such as embryonic and induced pluripotent stem cells. Furthermore, it introduces new strategies combining complementary cell types, such as MSCs and CSCs/CPCs, which can yield synergistic effects to boost cardiac regeneration.

  1. Cardiac Regenerative Medicine: The Potential of a New Generation of Stem Cells

    PubMed Central

    Cambria, Elena; Steiger, Julia; Günter, Julia; Bopp, Annina; Wolint, Petra; Hoerstrup, Simon P.; Emmert, Maximilian Y.

    2016-01-01

    Cardiac stem cell therapy holds great potential to prompt myocardial regeneration in patients with ischemic heart disease. The selection of the most suitable cell type is pivotal for its successful application. Various cell types, including crude bone marrow mononuclear cells, skeletal myoblast, and hematopoietic and endothelial progenitors, have already advanced into the clinical arena based on promising results from different experimental and preclinical studies. However, most of these so-called first-generation cell types have failed to fully emulate the promising preclinical data in clinical trials, resulting in heterogeneous outcomes and a critical lack of translation. Therefore, different next-generation cell types are currently under investigation for the treatment of the diseased myocardium. This review article provides an overview of current stem cell therapy concepts, including the application of cardiac stem (CSCs) and progenitor cells (CPCs) and lineage commitment via guided cardiopoiesis from multipotent cells such as mesenchymal stem cells (MSCs) or pluripotent cells such as embryonic and induced pluripotent stem cells. Furthermore, it introduces new strategies combining complementary cell types, such as MSCs and CSCs/CPCs, which can yield synergistic effects to boost cardiac regeneration. PMID:27721703

  2. Exploring the Role of Calcium in Cardiac Cell Dynamics

    NASA Astrophysics Data System (ADS)

    Berger, Carolyn; Idriss, Salim; Rouze, Ned; Hall, David; Gauthier, Daniel

    2007-03-01

    Bifurcations in the electrical response of cardiac tissue can destabilize spatio-temporal waves of electrochemical activity in the heart, leading to tachycardia or even fibrillation. Therefore, it is important to understand the mechanisms that cause instabilities in cardiac tissue.Traditionally, researchers have focused on understanding how the transmembrane voltage is altered in response to an increase in pacing rate, i.e. a shorter time interval between propagating electrochemical waves. However, the dynamics of the transmembrane voltage are coupled to the activity of several ions that traverse the membrane. Therefore, to fully understand the mechanisms that drive these bifurcations, we must include an investigation of the ionic behavior. We will present our recent investigation of the role of intracellular calcium in an experimental testbed of frog ventricle. Calcium and voltage are measured simultaneously, allowing for the previous research regarding voltage to guide our understanding of the calcium dynamics.

  3. Restoring balance to B cells in ADA deficiency.

    PubMed

    Luning Prak, Eline T

    2012-06-01

    It is paradoxical that immunodeficiency disorders are associated with autoimmunity. Adenosine deaminase (ADA) deficiency, a cause of X-linked severe combined immunodeficiency (SCID), is a case in point. In this issue of the JCI, Sauer and colleagues investigate the B cell defects in ADA-deficient patients. They demonstrate that ADA patients receiving enzyme replacement therapy had B cell tolerance checkpoint defects. Remarkably, gene therapy with a retrovirus that expresses ADA resulted in the apparent correction of these defects, with normalization of peripheral B cell autoantibody frequencies. In vitro, agents that either block ADA or overexpress adenosine resulted in altered B cell receptor and TLR signaling. Collectively, these data implicate a B cell-intrinsic mechanism for alterations in B cell tolerance in the setting of partial ADA deficiency that is corrected by gene therapy.

  4. Chitosan hydrogel improves mesenchymal stem cell transplant survival and cardiac function following myocardial infarction in rats

    PubMed Central

    Xu, Bin; Li, Yang; Deng, Bo; Liu, Xiaojing; Wang, Lin; Zhu, Qing-Lei

    2017-01-01

    Myocardial infarction (MI) remains the leading cause of cardiovascular-associated mortality and morbidity. Improving the retention rate, survival and cardiomyocyte differentiation of mesenchymal stem cells (MSCs) is important in improving the treatment of patients with MI. In the present study, temperature-responsive chitosan hydrogel, an injectable scaffold, was used to deliver MSCs directly into the infarcted myocardium of rats following MI. Histopathology and immunohistochemical staining were used to evaluate cardiac cell survival and regeneration, and cardiac function was assessed using an echocardiograph. It was demonstrated that chitosan hydrogel increased graft size and cell retention in the ischemic heart, promoted MSCs to differentiate into cardiomyocytes and increased the effects of MSCs on neovasculature formation. Furthermore, chitosan hydrogel enhanced the effect of MSCs on the improvement of cardiac function and hemodynamics in the infarcted area of rats following MI. These findings suggest that chitosan hydrogel is an appropriate material to deliver MSCs into infarcted myocardium. PMID:28352335

  5. Embryonic stem cell-based cardiopatches improve cardiac function in infarcted rats.

    PubMed

    Vallée, Jean-Paul; Hauwel, Mathieu; Lepetit-Coiffé, Matthieu; Bei, Wang; Montet-Abou, Karin; Meda, Paolo; Gardier, Stephany; Zammaretti, Prisca; Kraehenbuehl, Thomas P; Herrmann, Francois; Hubbell, Jeffrey A; Jaconi, Marisa E

    2012-03-01

    Pluripotent stem cell-seeded cardiopatches hold promise for in situ regeneration of infarcted hearts. Here, we describe a novel cardiopatch based on bone morphogenetic protein 2-primed cardiac-committed mouse embryonic stem cells, embedded into biodegradable fibrin matrices and engrafted onto infarcted rat hearts. For in vivo tracking of the engrafted cardiac-committed cells, superparamagnetic iron oxide nanoparticles were magnetofected into the cells, thus enabling detection and functional evaluation by high-resolution magnetic resonance imaging. Six weeks after transplantation into infarcted rat hearts, both local (p < .04) and global (p < .015) heart function, as well as the left ventricular dilation (p < .0011), were significantly improved (p < .001) as compared with hearts receiving cardiopatches loaded with iron nanoparticles alone. Histological analysis revealed that the fibrin scaffolds had degraded over time and clusters of myocyte enhancer factor 2-positive cardiac-committed cells had colonized most of the infarcted myocardium, including the fibrotic area. De novo CD31-positive blood vessels were formed in the vicinity of the transplanted cardiopatch. Altogether, our data provide evidence that stem cell-based cardiopatches represent a promising therapeutic strategy to achieve efficient cell implantation and improved global and regional cardiac function after myocardial infarction.

  6. Pharmacologic and genetic strategies to enhance cell therapy for cardiac regeneration.

    PubMed

    Kanashiro-Takeuchi, Rosemeire M; Schulman, Ivonne Hernandez; Hare, Joshua M

    2011-10-01

    Cell-based therapy is emerging as an exciting potential therapeutic approach for cardiac regeneration following myocardial infarction (MI). As heart failure (HF) prevalence increases over time, development of new interventions designed to aid cardiac recovery from injury are crucial and should be considered more broadly. In this regard, substantial efforts to enhance the efficacy and safety of cell therapy are continuously growing along several fronts, including modifications to improve the reprogramming efficiency of inducible pluripotent stem cells (iPS), genetic engineering of adult stem cells, and administration of growth factors or small molecules to activate regenerative pathways in the injured heart. These interventions are emerging as potential therapeutic alternatives and/or adjuncts based on their potential to promote stem cell homing, proliferation, differentiation, and/or survival. Given the promise of therapeutic interventions to enhance the regenerative capacity of multipotent stem cells as well as specifically guide endogenous or exogenous stem cells into a cardiac lineage, their application in cardiac regenerative medicine should be the focus of future clinical research. This article is part of a special issue entitled "Key Signaling Molecules in Hypertrophy and Heart Failure."

  7. Challenges in identifying the best source of stem cells for cardiac regeneration therapy.

    PubMed

    Dixit, Parul; Katare, Rajesh

    2015-03-13

    The overall clinical cardiac regeneration experience suggests that stem cell therapy can be safely performed, but it also underlines the need for reproducible results for their effective use in a real-world scenario. One of the significant challenges is the identification and selection of the best suited stem cell type for regeneration therapy. Bone marrow mononuclear cells, bone marrow-derived mesenchymal stem cells, resident or endogenous cardiac stem cells, endothelial progenitor cells and induced pluripotent stem cells are some of the stem cell types which have been extensively tested for their ability to regenerate the lost myocardium. While most of these cell types are being evaluated in clinical trials for their safety and efficacy, results show significant heterogeneity in terms of efficacy. The enthusiasm surrounding regenerative medicine in the heart has been dampened by the reports of poor survival, proliferation, engraftment, and differentiation of the transplanted cells. Therefore, the primary challenge is to create clearcut evidence on what actually drives the improvement of cardiac function after the administration of stem cells. In this review, we provide an overview of different types of stem cells currently being considered for cardiac regeneration and discuss why associated factors such as practicality and difficulty in cell collection should also be considered when selecting the stem cells for transplantation. Next, we discuss how the experimental variables (type of disease, marker-based selection and use of different isolation techniques) can influence the study outcome. Finally, we provide an outline of the molecular and genetic approaches to increase the functional ability of stem cells before and after transplantation.

  8. 3, 4-dihydroxyl-phenyl lactic acid restores NADH dehydrogenase 1 α subunit 10 to ameliorate cardiac reperfusion injury.

    PubMed

    Yang, Xiao-Yuan; He, Ke; Pan, Chun-Shui; Li, Quan; Liu, Yu-Ying; Yan, Li; Wei, Xiao-Hong; Hu, Bai-He; Chang, Xin; Mao, Xiao-Wei; Huang, Dan-Dan; Wang, Li-Jun; Hu, Shui-Wang; Jiang, Yong; Wang, Guo-Cheng; Fan, Jing-Yu; Fan, Tai-Ping; Han, Jing-Yan

    2015-06-01

    The present study aimed to detect the role of 3, 4-dihydroxyl-phenyl lactic acid (DLA) during ischemia/reperfusion (I/R) induced myocardial injury with emphasis on the underlying mechanism of DLA antioxidant. Male Spragu-Dawley (SD) rats were subjected to left descending artery occlusion followed by reperfusion. Treatment with DLA ameliorated myocardial structure and function disorder, blunted the impairment of Complex I activity and mitochondrial function after I/R. The results of 2-D fluorescence difference gel electrophoresis revealed that DLA prevented the decrease in NDUFA10 expression, one of the subunits of Complex I. To find the target of DLA, the binding affinity of Sirtuin 1 (SIRT1) to DLA and DLA derivatives with replaced two phenolic hydroxyls was detected using surface plasmon resonance and bilayer interferometry. The results showed that DLA could activate SIRT1 after I/R probably by binding to this protein, depending on phenolic hydroxyl. Moreover, the importance of SIRT1 to DLA effectiveness was confirmed through siRNA transfection in vitro. These results demonstrated that DLA was able to prevent I/R induced decrease in NDUFA10 expression, improve Complex I activity and mitochondrial function, eventually attenuate cardiac structure and function injury after I/R, which was possibly related to its ability of binding to and activating SIRT1.

  9. T-cell post-transplantation lymphoproliferative disorders after cardiac transplantation: a single institutional experience.

    PubMed

    Draoua, H Y; Tsao, Lawrence; Mancini, Donna M; Addonizio, Linda J; Bhagat, Govind; Alobeid, Bachir

    2004-11-01

    Post-transplantation lymphoproliferative disorders (PTLDs) are a well-recognized and potentially life-threatening complication of solid organ transplantation. While the vast majority of PTLDs are B-cell lymphoproliferations, T-cell PTLDs are rarely seen. Among 898 patients receiving cardiac transplants between 1990 and 2003, 34 patients (3.8%) developed PTLDs with two (0.2%) T-cell PTLDs, 31 (3.5%) B-cell PTLDs and one (0.1%) natural killer cell PTLD. An additional three cases of T-cell PTLD were identified among all cardiac transplant patients followed at our institution. These T-cell PTLDs comprised a heterogeneous group of Epstein-Barr virus negative lymphoproliferations that developed late after transplantation and followed an aggressive course.

  10. Components of the interleukin-33/ST2 system are differentially expressed and regulated in human cardiac cells and in cells of the cardiac vasculature.

    PubMed

    Demyanets, Svitlana; Kaun, Christoph; Pentz, Richard; Krychtiuk, Konstantin A; Rauscher, Sabine; Pfaffenberger, Stefan; Zuckermann, Andreas; Aliabadi, Arezu; Gröger, Marion; Maurer, Gerald; Huber, Kurt; Wojta, Johann

    2013-07-01

    Interleukin-33 (IL-33) is a recently described member of the IL-1 family of cytokines, which was identified as a ligand for the ST2 receptor. Components of the IL-33/ST2 system were shown to be expressed in normal and pressure overloaded human myocardium, and soluble ST2 (sST2) has emerged as a prognostic biomarker in myocardial infarction and heart failure. However, expression and regulation of IL-33 in human adult cardiac myocytes and fibroblasts was not tested before. In this study we found that primary human adult cardiac fibroblasts (HACF) and human adult cardiac myocytes (HACM) constitutively express nuclear IL-33 that is released during cell necrosis. Tumor necrosis factor (TNF)-α, interferon (IFN)-γ and IL-1β significantly increased both IL-33 protein and IL-33 mRNA expression in HACF and HACM as well as in human coronary artery smooth muscle cells (HCASMC). The nuclear factor-κB (NF-κB) inhibitor dimethylfumarate inhibited TNF-α- and IL-1β-induced IL-33 production as well as nuclear translocation of p50 and p65 NF-κB subunits in these cells. Mitogen-activated protein/extracellular signal-regulated kinase inhibitor U0126 abrogated TNF-α-, IFN-γ-, and IL-1β-induced and Janus-activated kinase inhibitor I reduced IFN-γ-induced IL-33 production. We detected IL-33 mRNA in human myocardial tissue from patients undergoing heart transplantation (n=27) where IL-33 mRNA levels statistically significant correlated with IFN-γ (r=0.591, p=0.001) and TNF-α (r=0.408, p=0.035) mRNA expression. Endothelial cells in human heart expressed IL-33 as well as ST2 protein. We also reveal that human cardiac and vascular cells have different distribution patterns of ST2 isoforms (sST2 and transmembrane ST2L) mRNA expression and produce different amounts of sST2 protein. Both human macrovascular (aortic and coronary artery) and heart microvascular endothelial cells express specific mRNA for both ST2 isoforms (ST2L and sST2) and are a source for sST2 protein, whereas

  11. The modulation of cardiac progenitor cell function by hydrogel-dependent Notch1 activation.

    PubMed

    Boopathy, Archana V; Che, Pao Lin; Somasuntharam, Inthirai; Fiore, Vincent F; Cabigas, E Bernadette; Ban, Kiwon; Brown, Milton E; Narui, Yoshie; Barker, Thomas H; Yoon, Young-Sup; Salaita, Khalid; García, Andrés J; Davis, Michael E

    2014-09-01

    Myocardial infarction is the leading cause of death worldwide and phase I clinical trials utilizing cardiac progenitor cells (CPCs) have shown promising outcomes. Notch1 signaling plays a critical role in cardiac development and in the survival, cardiogenic lineage commitment, and differentiation of cardiac stem/progenitor cells. In this study, we functionalized self-assembling peptide (SAP) hydrogels with a peptide mimic of the Notch1 ligand Jagged1 (RJ) to evaluate the therapeutic benefit of CPC delivery in the hydrogels in a rat model of myocardial infarction. The behavior of CPCs cultured in the 3D hydrogels in vitro including gene expression, proliferation, and growth factor production was evaluated. Interestingly, we observed Notch1 activation to be dependent on hydrogel polymer density/stiffness with synergistic increase in presence of RJ. Our results show that RJ mediated Notch1 activation depending on hydrogel concentration differentially regulated cardiogenic gene expression, proliferation, and growth factor production in CPCs in vitro. In rats subjected to experimental myocardial infarction, improvement in acute retention and cardiac function was observed following cell therapy in RJ hydrogels compared to unmodified or scrambled peptide containing hydrogels. This study demonstrates the potential therapeutic benefit of functionalizing SAP hydrogels with RJ for CPC based cardiac repair.

  12. G-CSF displays restricted ability to promote Sca-1(+) cardiac stem cell proliferation in vitro.

    PubMed

    Luo, Haijian; Bassi, Giulio; Tessari, Maddalena; Yang, Zhenyu; Faggian, Giuseppe

    2014-12-01

    Granulocyte colony-stimulating factor (G-CSF) is a controversial chemical in cardiac cell therapy. Myocardial homing of mobilized bone marrow-derived cells is thought to play a critical role in observed G-CSF-induced cardiac repair; meanwhile, the activation of proliferative potential of cardiac stem cells (CSCs) residing in the heart is a significant challenge. The present study aims to investigate whether G-CSF receptor is expressed in adult resident Sca-1(+) CSCs and determine the effect of G-CSF treatment on the proliferation of CSCs. For cardiac cells isolation, 12-week-old male C57BL/6 mice were anesthetized in a chamber containing 2.5% isoflurane in oxygen, euthanized by CO2 inhalation and then sacrificed by cervical dislocation. Magnetic-activated cell sorting was employed to acquire highly purified Sca-1(+) CSCs. We found that G-CSF receptor was expressed in adult resident Sca-1(+) CSCs by immunofluorescence staining and Western blotting. Exposure of Sca-1(+) cells to G-CSF in the culture medium for 72 h induced time-dependent but self-limiting cell cycle acceleration with a restricted effect on the CSC proliferation. As a result, it has provided a new insight to focus on the association between cardiac G-CSF therapy and adult resident stem cell activation. It may suggest gaining a deeper insight into the mechanisms of the interaction between CSCs and G-CSF to develop a synergistic strategy based on resident stem cell and G-CSF therapy for heart disease.

  13. The role of antioxidation and immunomodulation in postnatal multipotent stem cell-mediated cardiac repair.

    PubMed

    Saparov, Arman; Chen, Chien-Wen; Beckman, Sarah A; Wang, Yadong; Huard, Johnny

    2013-08-06

    Oxidative stress and inflammation play major roles in the pathogenesis of coronary heart disease including myocardial infarction (MI). The pathological progression following MI is very complex and involves a number of cell populations including cells localized within the heart, as well as cells recruited from the circulation and other tissues that participate in inflammatory and reparative processes. These cells, with their secretory factors, have pleiotropic effects that depend on the stage of inflammation and regeneration. Excessive inflammation leads to enlargement of the infarction site, pathological remodeling and eventually, heart dysfunction. Stem cell therapy represents a unique and innovative approach to ameliorate oxidative stress and inflammation caused by ischemic heart disease. Consequently, it is crucial to understand the crosstalk between stem cells and other cells involved in post-MI cardiac tissue repair, especially immune cells, in order to harness the beneficial effects of the immune response following MI and further improve stem cell-mediated cardiac regeneration. This paper reviews the recent findings on the role of antioxidation and immunomodulation in postnatal multipotent stem cell-mediated cardiac repair following ischemic heart disease, particularly acute MI and focuses specifically on mesenchymal, muscle and blood-vessel-derived stem cells due to their antioxidant and immunomodulatory properties.

  14. A Mouse Model for Fetal Maternal Stem Cell Transfer During Ischemic Cardiac Injury

    PubMed Central

    Kara, Rina J.; Bolli, Paola; Matsunaga, Iwao; Tanweer, Omar; Altman, Perry; Chaudhry, Hina W.

    2012-01-01

    Fetal cells enter the maternal circulation during pregnancies and can persist in blood and tissues for decades, creating a state of physiologic microchimerism. Microchimerism refers to acquisition of cells from another individual and can be due to bi-directional cell traffic between mother and fetus during pregnancy. Peripartum cardiomyopathy, a rare cardiac disorder associated with high mortality rates has the highest recovery rate amongst all etiologies of heart failure although the reason is unknown. Collectively, these observations led us to hypothesize that fetal cells enter the maternal circulation and may be recruited to the sites of myocardial disease or injury. The ability to genetically modify mice makes them an ideal system for studying the phenomenon of microchimerism in cardiac disease. Described here is a mouse model for ischemic cardiac injury during pregnancy designed to study microchimerism. Wild-type virgin female mice mated with eGFP male mice underwent ligation of the left anterior descending artery to induce a myocardial infarction at gestation day 12. We demonstrate the selective homing of eGFP cells to the site of cardiac injury without such homing to nonfinjured tissues suggesting the presence of precise signals sensed by fetal cells enabling them to target diseased myocardium specifically. PMID:22883609

  15. Impact of Cell Composition and Geometry on Human Induced Pluripotent Stem Cells-Derived Engineered Cardiac Tissue

    PubMed Central

    Nakane, Takeichiro; Masumoto, Hidetoshi; Tinney, Joseph P.; Yuan, Fangping; Kowalski, William J.; Ye, Fei; LeBlanc, Amanda J.; Sakata, Ryuzo; Yamashita, Jun K.; Keller, Bradley B.

    2017-01-01

    The current study describes a scalable, porous large-format engineered cardiac tissue (LF-ECT) composed of human induced pluripotent stem cells (hiPSCs) derived multiple lineage cardiac cells with varied 3D geometries and cell densities developed towards the goal of scale-up for large animal pre-clinical studies. We explored multiple 15 × 15 mm ECT geometries using molds with rectangular internal staggered posts (mesh, ME), without posts (plain sheet, PS), or long parallel posts (multiple linear bundles, ML) and a gel matrix containing hiPSC-derived cardiomyocytes, endothelial, and vascular mural cells matured in vitro for 14 days. ME-ECTs displayed the lowest dead cell ratio (p < 0.001) and matured into 0.5 mm diameter myofiber bundles with greater 3D cell alignment and higher active stress than PS-ECTs. Increased initial ECT cell number beyond 6 M per construct resulted in reduced cell survival and lower active stress. The 6M-ME-ECTs implanted onto 1 week post-infarct immune tolerant rat hearts engrafted, displayed evidence for host vascular coupling, and recovered myocardial structure and function with reduced scar area. We generated a larger (30 × 30 mm) ME-ECT to confirm scalability. Thus, large-format ECTs generated from hiPSC-derived cardiac cells may be feasible for large animal preclinical cardiac regeneration paradigms. PMID:28368043

  16. Trichostatin A enhances differentiation of human induced pluripotent stem cells to cardiogenic cells for cardiac tissue engineering.

    PubMed

    Lim, Shiang Y; Sivakumaran, Priyadharshini; Crombie, Duncan E; Dusting, Gregory J; Pébay, Alice; Dilley, Rodney J

    2013-09-01

    Human induced pluripotent stem (iPS) cells are a promising source of autologous cardiomyocytes to repair and regenerate myocardium for treatment of heart disease. In this study, we have identified a novel strategy to enhance cardiac differentiation of human iPS cells by treating embryoid bodies (EBs) with a histone deacetylase inhibitor, trichostatin A (TSA), together with activin A and bone morphogenetic protein 4 (BMP4). Over a narrow window of concentrations, TSA (1 ng/ml) directed the differentiation of human iPS cells into a cardiomyocyte lineage. TSA also exerted an additive effect with activin A (100 ng/ml) and BMP4 (20 ng/ml). The resulting cardiomyocytes expressed several cardiac-specific transcription factors and contractile proteins at both gene and protein levels. Functionally, the contractile EBs displayed calcium cycling and were responsive to the chronotropic agents isoprenaline (0.1 μM) and carbachol (1 μM). Implanting microdissected beating areas of iPS cells into tissue engineering chambers in immunocompromised rats produced engineered constructs that supported their survival, and they maintained spontaneous contraction. Human cardiomyocytes were identified as compact patches of muscle tissue incorporated within a host fibrocellular stroma and were vascularized by host neovessels. In conclusion, human iPS cell-derived cardiomyocytes can be used to engineer functional cardiac muscle tissue for studying the pathophysiology of cardiac disease, for drug discovery test beds, and potentially for generation of cardiac grafts to surgically replace damaged myocardium.

  17. Activin A Modulates CRIPTO-1/HNF4α+ Cells to Guide Cardiac Differentiation from Human Embryonic Stem Cells

    PubMed Central

    Duelen, Robin; Gilbert, Guillaume; Patel, Abdulsamie; de Schaetzen, Nathalie; De Waele, Liesbeth; Roderick, Llewelyn; Sipido, Karin R.; Verfaillie, Catherine M.; Buyse, Gunnar M.

    2017-01-01

    The use of human pluripotent stem cells in basic and translational cardiac research requires efficient differentiation protocols towards cardiomyocytes. In vitro differentiation yields heterogeneous populations of ventricular-, atrial-, and nodal-like cells hindering their potential applications in regenerative therapies. We described the effect of the growth factor Activin A during early human embryonic stem cell fate determination in cardiac differentiation. Addition of high levels of Activin A during embryoid body cardiac differentiation augmented the generation of endoderm derivatives, which in turn promoted cardiomyocyte differentiation. Moreover, a dose-dependent increase in the coreceptor expression of the TGF-β superfamily member CRIPTO-1 was observed in response to Activin A. We hypothesized that interactions between cells derived from meso- and endodermal lineages in embryoid bodies contributed to improved cell maturation in early stages of cardiac differentiation, improving the beating frequency and the percentage of contracting embryoid bodies. Activin A did not seem to affect the properties of cardiomyocytes at later stages of differentiation, measuring action potentials, and intracellular Ca2+ dynamics. These findings are relevant for improving our understanding on human heart development, and the proposed protocol could be further explored to obtain cardiomyocytes with functional phenotypes, similar to those observed in adult cardiac myocytes. PMID:28163723

  18. Rigid microenvironments promote cardiac differentiation of mouse and human embryonic stem cells

    NASA Astrophysics Data System (ADS)

    Arshi, Armin; Nakashima, Yasuhiro; Nakano, Haruko; Eaimkhong, Sarayoot; Evseenko, Denis; Reed, Jason; Stieg, Adam Z.; Gimzewski, James K.; Nakano, Atsushi

    2013-04-01

    While adult heart muscle is the least regenerative of tissues, embryonic cardiomyocytes are proliferative, with embryonic stem (ES) cells providing an endless reservoir. In addition to secreted factors and cell-cell interactions, the extracellular microenvironment has been shown to play an important role in stem cell lineage specification, and understanding how scaffold elasticity influences cardiac differentiation is crucial to cardiac tissue engineering. Though previous studies have analyzed the role of matrix elasticity on the function of differentiated cardiomyocytes, whether it affects the induction of cardiomyocytes from pluripotent stem cells is poorly understood. Here, we examine the role of matrix rigidity on cardiac differentiation using mouse and human ES cells. Culture on polydimethylsiloxane (PDMS) substrates of varied monomer-to-crosslinker ratios revealed that rigid extracellular matrices promote a higher yield of de novo cardiomyocytes from undifferentiated ES cells. Using a genetically modified ES system that allows us to purify differentiated cardiomyocytes by drug selection, we demonstrate that rigid environments induce higher cardiac troponin T expression, beating rate of foci, and expression ratio of adult α- to fetal β- myosin heavy chain in a purified cardiac population. M-mode and mechanical interferometry image analyses demonstrate that these ES-derived cardiomyocytes display functional maturity and synchronization of beating when co-cultured with neonatal cardiomyocytes harvested from a developing embryo. Together, these data identify matrix stiffness as an independent factor that instructs not only the maturation of already differentiated cardiomyocytes but also the induction and proliferation of cardiomyocytes from undifferentiated progenitors. Manipulation of the stiffness will help direct the production of functional cardiomyocytes en masse from stem cells for regenerative medicine purposes.

  19. Characterization of rat very small embryonic-like stem cells and cardiac repair after cell transplantation for myocardial infarction.

    PubMed

    Wu, Jin-Hong; Wang, Hai-Jie; Tan, Yu-Zhen; Li, Zhi-Hua

    2012-05-20

    Stem cell therapy is a promising therapeutic strategy for treating myocardial infarction (MI). However, it is necessary to identify ideal adult stem cells for transplantation and explore mechanisms of the transplanted cells in improving cardiac functions after MI. In this study, a population of embryonic-like stem cells (ELSCs) was isolated from rat bone marrow. The cells express pluripotent stem cell transcriptional factors and present high proliferative activity on mouse embryonic fibroblast feeder. ELSCs retain clonal expansion and may form embryoid-like bodies in soft agarose containing leukemia inhibitory factor and basic fibroblast growth factor. The cells of the embryoid-like bodies can differentiate into the cells from 3 germ layers. Under induction, the cells can differentiate into cardiomyocytes and endothelial cells. In MI models of female rats, the transplantation of preinduced ELSCs of male rats reduce scar area and improve cardiac function significantly. Comparing with marrow-derived mesenchymal stem cells and ELSCs without induction, effects of the preinduced ELSCs on myocardial repair and improvement of cardiac function are greater. Survival of the transplanted cells in the peri-infarcted and infarcted regions was examined by fluorescence in situ hybridization. Y chromosome-positive cells may differentiate toward cardiomyocytes and express cTnT and Cx43. Cx43 expression was observed at conjunction of Y chromosome-positive cells and recipient cardiomyocytes. Some Y chromosome-positive cells express CD31 and incorporate into the microvessels in the infarcted tissue. These results suggest that a population of ELSCs resides in rat bone marrow and display similar biological characteristics of ESCs. ELSCs can differentiate into cardiomyocytes and endothelial cells and contribute to cardiomyogenesis and angiogenesis in vivo. Cardiac function after MI may be significantly improved with transplantation of the preinduced ELSCs. Therefore, ELSCs are novel seed

  20. Cardiac repair in a mouse model of acute myocardial infarction with trophoblast stem cells

    PubMed Central

    Li, Guannan; Chen, Jianzhou; Zhang, Xinlin; He, Guixin; Tan, Wei; Wu, Han; Li, Ran; Chen, Yuhan; Gu, Rong; Xie, Jun; Xu, Biao

    2017-01-01

    Various stem cells have been explored for the purpose of cardiac repair. However, any individual stem cell population has not been considered as the ideal source. Recently, trophoblast stem cells (TSCs), a newly described stem cell type, have demonstrated extensive plasticity. The present study evaluated the therapeutic effect of TSCs transplantation for heart regeneration in a mouse model of myocardial infarction (MI) and made a direct comparison with the most commonly used mesenchymal stem cells (MSCs). Transplantation of TSCs and MSCs led to a remarkably improved cardiac function in contrast with the PBS control, but only the TSCs exhibited the potential of differentiation into cardiomyocytes in vivo. In addition, a significantly high proliferation level of both transplanted stem cells and resident cardiomyocytes was observed in the TSCs group. These findings primary revealed the therapeutic potential of TSCs in transplantation therapy for MI. PMID:28295048

  1. The structure and distribution of satellite cells of cardiac muscles in decapod crustaceans.

    PubMed

    Midsukami, M

    1981-01-01

    The structure and distribution of satellite cells of cardiac muscles were examined in twenty-one species of animals chosen from each tribe within the order Decapoda (Arthropoda, Crustacea). The satellite cells were found in all animals observed. Most of them are morphologically identical with those described in different striated muscles of other species, but some cells have unusual features. The decapod satellite cell occasionally lies right over the region corresponding to the intercalated disc between the apposed cardiac muscle cells. The cell sends cytoplasmic processes into the adjacent muscle cells, enabling the plasma membrane to make close contact with the cleft opening of the intercalated disc, and with the myofibril at the level of the Z-line. Another characteristic feature is the presence of "paired" cells. Such cells are clearly separated from each other over most of the contact area by the respective plasma membranes, which are smooth in appearance and devoid of specialized regions. The significance of the presence of satellite cells in decapod cardiac muscle and its possible role are discussed and compared with those described for other species.

  2. A role for matrix stiffness in the regulation of cardiac side population cell function.

    PubMed

    Qiu, Yiling; Bayomy, Ahmad F; Gomez, Marcus V; Bauer, Michael; Du, Ping; Yang, Yanfei; Zhang, Xin; Liao, Ronglih

    2015-05-01

    The mechanical properties of the local microenvironment may have important influence on the fate and function of adult tissue progenitor cells, altering the regenerative process. This is particularly critical following a myocardial infarction, in which the normal, compliant myocardial tissue is replaced with fibrotic, stiff scar tissue. In this study, we examined the effects of matrix stiffness on adult cardiac side population (CSP) progenitor cell behavior. Ovine and murine CSP cells were isolated and cultured on polydimethylsiloxane substrates, replicating the elastic moduli of normal and fibrotic myocardium. Proliferation capacity and cell cycling were increased in CSP cells cultured on the stiff substrate with an associated reduction in cardiomyogeneic differentiation and accelerated cell ageing. In addition, culture on stiff substrate stimulated upregulation of extracellular matrix and adhesion proteins gene expression in CSP cells. Collectively, we demonstrate that microenvironment properties, including matrix stiffness, play a critical role in regulating progenitor cell functions of endogenous resident CSP cells. Understanding the effects of the tissue microenvironment on resident cardiac progenitor cells is a critical step toward achieving functional cardiac regeneration.

  3. Activation of cardiac progenitor cells through paracrine effects of mesenchymal stem cells

    SciTech Connect

    Nakanishi, Chiaki; Yamagishi, Masakazu; Yamahara, Kenichi; Hagino, Ikuo; Mori, Hidezo; Sawa, Yoshiki; Yagihara, Toshikatsu; Kitamura, Soichiro; Nagaya, Noritoshi

    2008-09-12

    Mesenchymal stem cells (MSC) transplantation has been proved to be promising strategy to treat the failing heart. The effect of MSC transplantation is thought to be mediated mainly in a paracrine manner. Recent reports have suggested that cardiac progenitor cells (CPC) reside in the heart. In this study, we investigated whether MSC had paracrine effects on CPC in vitro. CPC were isolated from the neonatal rat heart using an explant method. MSC were isolated from the adult rat bone marrow. MSC-derived conditioned medium promoted proliferation of CPC and inhibited apoptosis of CPC induced by hypoxia and serum starvation. Chemotaxis chamber assay demonstrated that MSC-derived conditioned medium enhanced migration of CPC. Furthermore, MSC-derived conditioned medium upregulated expression of cardiomyocyte-related genes in CPC such as {beta}-myosin heavy chain ({beta}-MHC) and atrial natriuretic peptide (ANP). In conclusion, MSC-derived conditioned medium had protective effects on CPC and enhanced their migration and differentiation.

  4. Induced Pluripotent Stem Cells Restore Function in a Human Cell Loss Model of Open-Angle Glaucoma

    PubMed Central

    Abu-Hassan, Diala W; Li, Xinbo; Ryan, Eileen I; Acott, Ted S; Kelley, Mary J

    2015-01-01

    Normally, trabecular meshwork (TM) and Schlemm's canal inner wall endothelial cells within the aqueous humor outflow pathway maintain intraocular pressure within a narrow safe range. Elevation in intraocular pressure, because of the loss of homeostatic regulation by these outflow pathway cells, is the primary risk factor for vision loss due to glaucomatous optic neuropathy. A notable feature associated with glaucoma is outflow pathway cell loss. Using controlled cell loss in ex vivo perfused human outflow pathway organ culture, we developed compelling experimental evidence that this level of cell loss compromises intraocular pressure homeostatic function. This function was restored by repopulation of the model with fresh TM cells. We then differentiated induced pluripotent stem cells (iPSCs) and used them to repopulate this cell depletion model. These differentiated cells (TM-like iPSCs) became similar to TM cells in both morphology and expression patterns. When transplanted, they were able to fully restore intraocular pressure homeostatic function. This successful transplantation of TM-like iPSCs establishes the conceptual feasibility of using autologous stem cells to restore intraocular pressure regulatory function in open-angle glaucoma patients, providing a novel alternative treatment option. Stem Cells 2015;33:751–761 PMID:25377070

  5. Wnt/β-Catenin Stimulation and Laminins Support Cardiovascular Cell Progenitor Expansion from Human Fetal Cardiac Mesenchymal Stromal Cells

    PubMed Central

    Månsson-Broberg, Agneta; Rodin, Sergey; Bulatovic, Ivana; Ibarra, Cristián; Löfling, Marie; Genead, Rami; Wärdell, Eva; Felldin, Ulrika; Granath, Carl; Alici, Evren; Le Blanc, Katarina; Smith, C.I. Edvard; Salašová, Alena; Westgren, Magnus; Sundström, Erik; Uhlén, Per; Arenas, Ernest; Sylvén, Christer; Tryggvason, Karl; Corbascio, Matthias; Simonson, Oscar E.; Österholm, Cecilia; Grinnemo, Karl-Henrik

    2016-01-01

    Summary The intrinsic regenerative capacity of human fetal cardiac mesenchymal stromal cells (MSCs) has not been fully characterized. Here we demonstrate that we can expand cells with characteristics of cardiovascular progenitor cells from the MSC population of human fetal hearts. Cells cultured on cardiac muscle laminin (LN)-based substrata in combination with stimulation of the canonical Wnt/β-catenin pathway showed increased gene expression of ISL1, OCT4, KDR, and NKX2.5. The majority of cells stained positive for PDGFR-α, ISL1, and NKX2.5, and subpopulations also expressed the progenitor markers TBX18, KDR, c-KIT, and SSEA-1. Upon culture of the cardiac MSCs in differentiation media and on relevant LNs, portions of the cells differentiated into spontaneously beating cardiomyocytes, and endothelial and smooth muscle-like cells. Our protocol for large-scale culture of human fetal cardiac MSCs enables future exploration of the regenerative functions of these cells in the context of myocardial injury in vitro and in vivo. PMID:27052314

  6. Wnt/β-Catenin Stimulation and Laminins Support Cardiovascular Cell Progenitor Expansion from Human Fetal Cardiac Mesenchymal Stromal Cells.

    PubMed

    Månsson-Broberg, Agneta; Rodin, Sergey; Bulatovic, Ivana; Ibarra, Cristián; Löfling, Marie; Genead, Rami; Wärdell, Eva; Felldin, Ulrika; Granath, Carl; Alici, Evren; Le Blanc, Katarina; Smith, C I Edvard; Salašová, Alena; Westgren, Magnus; Sundström, Erik; Uhlén, Per; Arenas, Ernest; Sylvén, Christer; Tryggvason, Karl; Corbascio, Matthias; Simonson, Oscar E; Österholm, Cecilia; Grinnemo, Karl-Henrik

    2016-04-12

    The intrinsic regenerative capacity of human fetal cardiac mesenchymal stromal cells (MSCs) has not been fully characterized. Here we demonstrate that we can expand cells with characteristics of cardiovascular progenitor cells from the MSC population of human fetal hearts. Cells cultured on cardiac muscle laminin (LN)-based substrata in combination with stimulation of the canonical Wnt/β-catenin pathway showed increased gene expression of ISL1, OCT4, KDR, and NKX2.5. The majority of cells stained positive for PDGFR-α, ISL1, and NKX2.5, and subpopulations also expressed the progenitor markers TBX18, KDR, c-KIT, and SSEA-1. Upon culture of the cardiac MSCs in differentiation media and on relevant LNs, portions of the cells differentiated into spontaneously beating cardiomyocytes, and endothelial and smooth muscle-like cells. Our protocol for large-scale culture of human fetal cardiac MSCs enables future exploration of the regenerative functions of these cells in the context of myocardial injury in vitro and in vivo.

  7. Calcitriol restores antiestrogen responsiveness in estrogen receptor negative breast cancer cells: A potential new therapeutic approach

    PubMed Central

    2014-01-01

    Background Approximately 30% of breast tumors do not express the estrogen receptor (ER) α, which is necessary for endocrine therapy approaches. Studies are ongoing in order to restore ERα expression in ERα-negative breast cancer. The aim of the present study was to determine if calcitriol induces ERα expression in ER-negative breast cancer cells, thus restoring antiestrogen responses. Methods Cultured cells derived from ERα-negative breast tumors and an ERα-negative breast cancer cell line (SUM-229PE) were treated with calcitriol and ERα expression was assessed by real time PCR and western blots. The ERα functionality was evaluated by prolactin gene expression analysis. In addition, the effects of antiestrogens were assessed by growth assay using the XTT method. Gene expression of cyclin D1 (CCND1), and Ether-à-go-go 1 (EAG1) was also evaluated in cells treated with calcitriol alone or in combination with estradiol or ICI-182,780. Statistical analyses were determined by one-way ANOVA. Results Calcitriol was able to induce the expression of a functional ERα in ER-negative breast cancer cells. This effect was mediated through the vitamin D receptor (VDR), since it was abrogated by a VDR antagonist. Interestingly, the calcitriol-induced ERα restored the response to antiestrogens by inhibiting cell proliferation. In addition, calcitriol-treated cells in the presence of ICI-182,780 resulted in a significant reduction of two important cell proliferation regulators CCND1 and EAG1. Conclusions Calcitriol induced the expression of ERα and restored the response to antiestrogens in ERα-negative breast cancer cells. The combined treatment with calcitriol and antiestrogens could represent a new therapeutic strategy in ERα-negative breast cancer patients. PMID:24678876

  8. The infarcted cardiac microenvironment cannot selectively promote embryonic stem cell differentiation into cardiomyocytes.

    PubMed

    Chen, You-Ren; Li, Yang; Chen, Li; Yang, Xin-Chun; Su, Pi-Xiong; Cai, Jun

    2011-01-01

    Postinfarct congestive heart failure is one of the leading causes of morbidity and mortality in industrialized countries. It is controversial whether embryonic stem cells are feasible sources for in situ cardiac regeneration in infarcted hearts. In order to investigate whether the infarcted cardiac microenvironment could selectively promote embryonic stem cell differentiation into cardiomyocytes, we assessed the cardiac differentiation potential of mouse embryonic stem cells (mESCs) injected into normal (n=16) or acutely infarcted rat hearts (n=18). We found that the transplanted 4',6-diamidino-2-phenylindole (DAPI)-labeled mESCs were able to survive and form stable intracardiac grafts both in normal and infarcted hearts, along with macrophages found specifically in the engraftment area. Two to four weeks after mESC transplantation, we found that more DAPI-positive mESCs differentiated into cardiomyocytes, marked by cardiac troponin T (cTnT), in normal than those in infarcted hearts (2.67±0.79% vs. 1.06±0.52%, P<.01). However, the discrepancy between the percentage of DAPI-positive cells that express cTnT in normal and that in infarcted hearts was diminished after 4 weeks (1.17±0.98% vs. 1.07±1.02%, P>.05), when the transverse striation began to present in the mESCs-derived cardiomyocytes. In addition, mESCs differentiated into vimentin-positive cardiac fibroblasts in normal and infracted hearts. Our results indicated that transplanted mESCs cannot only survive but differentiate into cardiomyocytes in infarcted rat hearts. However, the infarcted cardiac microenvironment cannot selectively promote mESCs differentiation into cardiomyocytes.

  9. Functional tooth restoration by allogeneic mesenchymal stem cell-based bio-root regeneration in swine.

    PubMed

    Wei, Fulan; Song, Tieli; Ding, Gang; Xu, Junji; Liu, Yi; Liu, Dayong; Fan, Zhipeng; Zhang, Chunmei; Shi, Songtao; Wang, Songlin

    2013-06-15

    Our previous proof-of-concept study showed the feasibility of regenerating the dental stem cell-based bioengineered tooth root (bio-root) structure in a large animal model. Here, we used allogeneic dental mesenchymal stem cells to regenerate bio-root, and then installed a crown on the bio-root to restore tooth function. A root shape hydroxyapatite tricalcium phosphate scaffold containing dental pulp stem cells was covered by a Vc-induced periodontal ligament stem cell sheet and implanted into a newly generated jaw bone implant socket. Six months after implantation, a prefabricated porcelain crown was cemented to the implant and subjected to tooth function. Clinical, radiological, histological, ultrastructural, systemic immunological evaluations and mechanical properties were analyzed for dynamic changes in the bio-root structure. The regenerated bio-root exhibited characteristics of a normal tooth after 6 months of use, including dentinal tubule-like and functional periodontal ligament-like structures. No immunological response to the bio-roots was observed. We developed a standard stem cell procedure for bio-root regeneration to restore adult tooth function. This study is the first to successfully regenerate a functional bio-root structure for artificial crown restoration by using allogeneic dental stem cells and Vc-induced cell sheet, and assess the recipient immune response in a preclinical model.

  10. Rigid microenvironments promote cardiac differentiation of mouse and human embryonic stem cells

    PubMed Central

    Arshi, Armin; Nakashima, Yasuhiro; Nakano, Haruko; Eaimkhong, Sarayoot; Evseenko, Denis; Reed, Jason; Stieg, Adam Z; Gimzewski, James K; Nakano, Atsushi

    2013-01-01

    While adult heart muscle is the least regenerative of tissues, embryonic cardiomyocytes are proliferative, with embryonic stem (ES) cells providing an endless reservoir. In addition to secreted factors and cell–cell interactions, the extracellular microenvironment has been shown to play an important role in stem cell lineage specification, and understanding how scaffold elasticity influences cardiac differentiation is crucial to cardiac tissue engineering. Though previous studies have analyzed the role of matrix elasticity on the function of differentiated cardiomyocytes, whether it affects the induction of cardiomyocytes from pluripotent stem cells is poorly understood. Here, we examine the role of matrix rigidity on cardiac differentiation using mouse and human ES cells. Culture on polydimethylsiloxane (PDMS) substrates of varied monomer-to-crosslinker ratios revealed that rigid extracellular matrices promote a higher yield of de novo cardiomyocytes from undifferentiated ES cells. Using a genetically modified ES system that allows us to purify differentiated cardiomyocytes by drug selection, we demonstrate that rigid environments induce higher cardiac troponin T expression, beating rate of foci, and expression ratio of adult α- to fetal β- myosin heavy chain in a purified cardiac population. M-mode and mechanical interferometry image analyses demonstrate that these ES-derived cardiomyocytes display functional maturity and synchronization of beating when co-cultured with neonatal cardiomyocytes harvested from a developing embryo. Together, these data identify matrix stiffness as an independent factor that instructs not only the maturation of already differentiated cardiomyocytes but also the induction and proliferation of cardiomyocytes from undifferentiated progenitors. Manipulation of the stiffness will help direct the production of functional cardiomyocytes en masse from stem cells for regenerative medicine purposes. PMID:24311969

  11. Cardiac complications after haploidentical HLA-mismatched hematopoietic stem cell transplantation using in vivo alemtuzumab.

    PubMed

    Oshima, K; Sakata-Yanagimoto, M; Asano-Mori, Y; Izutsu, K; Watanabe, T; Shoda, E; Ogawa, S; Motokura, T; Chiba, S; Kurokawa, M; Hirai, H; Kanda, Y

    2005-11-01

    Alemtuzumab is a humanized monoclonal antibody directed against human CD52 with a strong lympholytic effect. We have performed unmanipulated hematopoietic stem cell transplantation (HSCT) from 2- or 3-locus-mismatched family donors in 14 patients using in vivo alemtuzumab. All achieved complete donor cell engraftment and grade III-IV acute graft-versus-host disease was observed in only one patient. However, eight of the 14 patients developed grade II-IV cardiac complications according to Bearman's criteria. Next, we retrospectively analyzed the records of 142 adult patients who underwent allogeneic HSCT from 1995 to 2004 to evaluate whether the use of alemtuzumab was an independent risk factor for cardiac complications. Among several factors that increased the incidence of grade II-IV cardiac complications with at least borderline significance, a multivariate analysis identified the cumulative dose of anthracyclines (P=0.0016) and the use of alemtuzumab (P=0.0001) as independent significant risk factors. All of the cardiac complications in the alemtuzumab group were successfully treated with diuretics and/or catecholamines. Patient selection and close monitoring of cardiac function may be important in HLA-mismatched HSCT using in vivo alemtuzumab.

  12. Functional properties of cells obtained from human cord blood CD34+ stem cells and mouse cardiac myocytes in coculture.

    PubMed

    Orlandi, Alessia; Pagani, Francesca; Avitabile, Daniele; Bonanno, Giuseppina; Scambia, Giovanni; Vigna, Elisa; Grassi, Francesca; Eusebi, Fabrizio; Fucile, Sergio; Pesce, Maurizio; Capogrossi, Maurizio C

    2008-04-01

    Prior in vitro studies suggested that different types of hematopoietic stem cells may differentiate into cardiomyocytes. The present work examined whether human CD34(+) cells from the human umbilical cord blood (hUCB), cocultured with neonatal mouse cardiomyocytes, acquire the functional properties of myocardial cells and express human cardiac genes. hUCB CD34(+) cells were cocultured onto cardiomyocytes following an infection with a lentivirus-encoding enhanced green fluorescent protein (EGFP). After 7 days, mononucleated EGFP(+) cells were tested for their electrophysiological features by patch clamp and for cytosolic [Ca(2+)] ([Ca(2+)](i)) homeostasis by [Ca(2+)](i) imaging of X-rhod1-loaded cells. Human Nkx2.5 and GATA-4 expression was examined in cocultured cell populations by real-time RT-PCR. EGFP(+) cells were connected to surrounding cells by gap junctions, acquired electrophysiological properties similar to those of cardiomyocytes, and showed action potential-associated [Ca(2+)](i) transients. These cells also exhibited spontaneous sarcoplasmic reticulum [Ca(2+)](i) oscillations and the associated membrane potential depolarization. However, RT-PCR of both cell populations showed no upregulation of human-specific cardiac genes. In conclusion, under our experimental conditions, hUCB CD34(+) cells cocultured with murine cardiomyocytes formed cells that exhibited excitation-contraction coupling features similar to those of cardiomyocytes. However, the expression of human-specific cardiac genes was undetectable by RT-PCR.

  13. Induced pluripotent stem cells restore function in a human cell loss model of open-angle glaucoma.

    PubMed

    Abu-Hassan, Diala W; Li, Xinbo; Ryan, Eileen I; Acott, Ted S; Kelley, Mary J

    2015-03-01

    Normally, trabecular meshwork (TM) and Schlemm's canal inner wall endothelial cells within the aqueous humor outflow pathway maintain intraocular pressure within a narrow safe range. Elevation in intraocular pressure, because of the loss of homeostatic regulation by these outflow pathway cells, is the primary risk factor for vision loss due to glaucomatous optic neuropathy. A notable feature associated with glaucoma is outflow pathway cell loss. Using controlled cell loss in ex vivo perfused human outflow pathway organ culture, we developed compelling experimental evidence that this level of cell loss compromises intraocular pressure homeostatic function. This function was restored by repopulation of the model with fresh TM cells. We then differentiated induced pluripotent stem cells (iPSCs) and used them to repopulate this cell depletion model. These differentiated cells (TM-like iPSCs) became similar to TM cells in both morphology and expression patterns. When transplanted, they were able to fully restore intraocular pressure homeostatic function. This successful transplantation of TM-like iPSCs establishes the conceptual feasibility of using autologous stem cells to restore intraocular pressure regulatory function in open-angle glaucoma patients, providing a novel alternative treatment option.

  14. Mitochondrial genome acquisition restores respiratory function and tumorigenic potential of cancer cells without mitochondrial DNA.

    PubMed

    Tan, An S; Baty, James W; Dong, Lan-Feng; Bezawork-Geleta, Ayenachew; Endaya, Berwini; Goodwin, Jacob; Bajzikova, Martina; Kovarova, Jaromira; Peterka, Martin; Yan, Bing; Pesdar, Elham Alizadeh; Sobol, Margarita; Filimonenko, Anatolyj; Stuart, Shani; Vondrusova, Magdalena; Kluckova, Katarina; Sachaphibulkij, Karishma; Rohlena, Jakub; Hozak, Pavel; Truksa, Jaroslav; Eccles, David; Haupt, Larisa M; Griffiths, Lyn R; Neuzil, Jiri; Berridge, Michael V

    2015-01-06

    We report that tumor cells without mitochondrial DNA (mtDNA) show delayed tumor growth, and that tumor formation is associated with acquisition of mtDNA from host cells. This leads to partial recovery of mitochondrial function in cells derived from primary tumors grown from cells without mtDNA and a shorter lag in tumor growth. Cell lines from circulating tumor cells showed further recovery of mitochondrial respiration and an intermediate lag to tumor growth, while cells from lung metastases exhibited full restoration of respiratory function and no lag in tumor growth. Stepwise assembly of mitochondrial respiratory (super)complexes was correlated with acquisition of respiratory function. Our findings indicate horizontal transfer of mtDNA from host cells in the tumor microenvironment to tumor cells with compromised respiratory function to re-establish respiration and tumor-initiating efficacy. These results suggest pathophysiological processes for overcoming mtDNA damage and support the notion of high plasticity of malignant cells.

  15. Restoration of Chloride Efflux by Azithromycin in Airway Epithelial Cells of Cystic Fibrosis Patients▿

    PubMed Central

    Saint-Criq, Vinciane; Rebeyrol, Carine; Ruffin, Manon; Roque, Telma; Guillot, Loïc; Jacquot, Jacky; Clement, Annick; Tabary, Olivier

    2011-01-01

    Azithromycin (AZM) has shown promising anti-inflammatory properties in chronic obstructive pulmonary diseases, and clinical studies have presented an improvement in the respiratory condition of cystic fibrosis (CF) patients. The aim of this study was to investigate, in human airway cells, the mechanism by which AZM has beneficial effects in CF. We demonstrated that AZM did not have any anti-inflammatory effect on CF airway cells but restored Cl− efflux. PMID:21220528

  16. A Temporal Chromatin Signature in Human Embryonic Stem Cells Identifies Regulators of Cardiac Development

    PubMed Central

    Paige, Sharon L.; Thomas, Sean; Stoick-Cooper, Cristi L.; Wang, Hao; Maves, Lisa; Sandstrom, Richard; Pabon, Lil; Reinecke, Hans; Pratt, Gabriel; Keller, Gordon; Moon, Randall T.; Stamatoyannopoulos, John; Murry, Charles E.

    2012-01-01

    Summary Directed differentiation of human embryonic stem cells (ESCs) into cardiovascular cells provides a model for studying molecular mechanisms of human cardiovascular development. Though it is known that chromatin modification patterns in ESCs differ markedly from those in lineage-committed progenitors and differentiated cells, the temporal dynamics of chromatin alterations during differentiation along a defined lineage have not been studied. We show that differentiation of human ESCs into cardiovascular cells is accompanied by programmed temporal alterations in chromatin structure that distinguish key regulators of cardiovascular development from other genes. We used this temporal chromatin signature to identify regulators of cardiac development, including the homeobox gene MEIS2. We demonstrate using the zebrafish model that MEIS2 is critical for proper heart tube formation and subsequent cardiac looping. Temporal chromatin signatures should be broadly applicable to other models of stem cell differentiation to identify regulators and provide key insights into major developmental decisions. PMID:22981225

  17. TBX1 Represses Vegfr2 Gene Expression and Enhances the Cardiac Fate of VEGFR2+ Cells

    PubMed Central

    Lania, Gabriella; Ferrentino, Rosa; Baldini, Antonio

    2015-01-01

    The T-box transcription factor TBX1 has critical roles in maintaining proliferation and inhibiting differentiation of cardiac progenitor cells of the second heart field (SHF). Haploinsufficiency of the gene that encodes it is a cause of congenital heart disease. Here, we developed an embryonic stem (ES) cell-based model in which Tbx1 expression can be modulated by tetracycline. Using this model, we found that TBX1 down regulates the expression of VEGFR2, and we confirmed this finding in vivo during embryonic development. In addition, we found a Vegfr2 domain of expression, not previously described, in the posterior SHF and this expression is extended by loss of Tbx1. VEGFR2 has been previously described as a marker of a subpopulation of cardiac progenitors. Clonal analysis of ES-derived VEGFR2+ cells indicated that 12.5% of clones expressed three markers of cardiac lineage (cardiomyocyte, smooth muscle and endothelium). However, a pulse of Tbx1 expression was sufficient to increase the percentage to 20.8%. In addition, the percentage of clones expressing markers of multiple cardiac lineages increased from 41.6% to 79.1% after Tbx1 pulse. These results suggest that TBX1 plays a role in maintaining a progenitor state in VEGFR2+ cells. PMID:26382615

  18. Cardiac stem cell biology: glimpse of the past, present, and future.

    PubMed

    Matsa, Elena; Sallam, Karim; Wu, Joseph C

    2014-01-03

    Cardiac regeneration strategies and de novo generation of cardiomyocytes have long been significant areas of research interest in cardiovascular medicine. In this review, we outline a variety of common cell sources and methods used to regenerate cardiomyocytes and highlight the important role that key Circulation Research articles have played in this flourishing field.

  19. Expression and significance of fgl2 prothrombinase in cardiac microvascular endothelial cells of rats with type 2 diabetes.

    PubMed

    Ding, Yanping; Liu, Kun; Wang, Yan; Su, Guanhua; Deng, Heping; Zeng, Qiutang; Liao, Yuhua; Wang, Zhaohui

    2010-10-01

    Microthrombosis may be involved in the pathogenesis of cardiac microangiopathy due to diabetes. Recent studies have shown that fibrinogen-like protein 2 (fgl2) plays a pivotal role in microthrombosis in viral hepatitis, acute vascular xenograft rejection and cytokine-induced fetal loss syndrome. The current study was designed to examine the expression of fgl2 in microvascular endothelial cells and investigate the effects of microthrombi due to fgl2 on cardiac function and structure in rats with type 2 diabetes. Following induction of type 2 diabetes, 24 rats were observed dynamically. Fgl2 expression and related cardiac microthrombosis were examined. Local or circulating TNF-α was measured. Coronary flow (CF) per min was calculated as an index of cardiac microcirculation. Cardiac function and morphology were evaluated. It was found that Fgl2 was highly expressed in cardiac microvascular endothelial cells of rats with type 2 diabetes, which was promoted by local or circulating TNF-α. The Fgl2 expression was associated with cardiac hyaline microthrombosis. In parallel with the fgl2 expression, CF per min, cardiac diastolic or systolic function and cardiac morphology were aggravated to some extent. It was concluded that in rats with type 2 diabetes, microthrombosis due to fgl2 contributes to the impairment of cardiac diastolic or systolic function and morphological changes.

  20. Myeloid cells that impair immunotherapy are restored in melanomas which acquire resistance to BRAF inhibitors.

    PubMed

    Steinberg, Shannon M; Shabaneh, Tamer; Zhang, Peisheng; Martyanov, Viktor; Li, Zhenghui; Malik, Brian; Wood, Tammara; Boni, Andrea; Molodtsov, Aleksey; Angeles, Christina V; Curiel, Tyler J; Whitfield, Michael; Turk, Mary Jo

    2017-02-15

    Acquired resistance to BRAFV600E inhibitors (BRAFi) in melanoma remains a common clinical obstacle, as is the case for any targeted drug therapy that can be developed given the plastic nature of cancers. While there has been significant focus on the cancer cell-intrinsic properties of BRAFi resistance, the impact of BRAFi resistance on host immunity has not been explored. Here we provide preclinical evidence that resistance to BRAFi in an autochthonous mouse model of melanoma is associated with restoration of myeloid-derived suppressor cells (MDSC) in the tumor microenvironment initially reduced by BRAFi treatment. In contrast to restoration of MDSC, levels of T regulatory cells remained reduced in BRAFi-resistant tumors. Accordingly, tumor gene expression signatures specific for myeloid cell chemotaxis and homeostasis reappeared in BRAFi-resistant tumors. Notably, MDSC restoration relied upon MAPK pathway reactivation and downstream production of the myeloid attractant CCL2 in BRAFi-resistant melanoma cells. Strikingly, while combination checkpoint blockade (anti-CTLA-4 + anti-PD-1) was ineffective against BRAFi-resistant melanomas, the addition of MDSC depletion/blockade (anti-Gr-1 + CCR2 antagonist) prevented outgrowth of BRAFi-resistant tumors. Our results illustrate how extrinsic pathways of immunosuppression elaborated by melanoma cells dominate the tumor microenvironment and highlight the need to target extrinsic as well as intrinsic mechanisms of drug resistance.

  1. GPR30 decreases cardiac chymase/angiotensin II by inhibiting local mast cell number

    SciTech Connect

    Zhao, Zhuo; Wang, Hao; Lin, Marina; Groban, Leanne

    2015-03-27

    Chronic activation of the novel estrogen receptor GPR30 by its agonist G1 mitigates the adverse effects of estrogen (E2) loss on cardiac structure and function. Using the ovariectomized (OVX) mRen2.Lewis rat, an E2-sensitive model of diastolic dysfunction, we found that E2 status is inversely correlated with local cardiac angiotensin II (Ang II) levels, likely via Ang I/chymase-mediated production. Since chymase is released from cardiac mast cells during stress (e.g., volume/pressure overload, inflammation), we hypothesized that GPR30-related cardioprotection after E2 loss might occur through its opposing actions on cardiac mast cell proliferation and chymase production. Using real-time quantitative PCR, immunohistochemistry, and immunoblot analysis, we found mast cell number, chymase expression, and cardiac Ang II levels were significantly increased in the hearts of OVX-compared to ovary-intact mRen2.Lewis rats and the GPR30 agonist G1 (50 mg/kg/day, s.c.) administered for 2 weeks limited the adverse effects of estrogen loss. In vitro studies revealed that GPR30 receptors are expressed in the RBL-2H3 mast cell line and G1 inhibits serum-induced cell proliferation in a dose-dependent manner, as determined by cell counting, BrdU incorporation assay, and Ki-67 staining. Using specific antagonists to estrogen receptors, blockage of GPR30, but not ERα or ERβ, attenuated the inhibitory effects of estrogen on BrdU incorporation in RBL-2H3 cells. Further study of the mechanism underlying the effect on cell proliferation showed that G1 inhibits cyclin-dependent kinase 1 (CDK1) mRNA and protein expression in RBL-2H3 cells in a dose-dependent manner. - Highlights: • GPR30 activation limits mast cell number in hearts from OVX mRen2.Lewis rats. • GPR30 activation decreases cardiac chymase/angiotensin II after estrogen loss. • GPR30 activation inhibits RBL-2H3 mast cell proliferation and CDK1 expression.

  2. Human spermatagonial stem cells: a novel therapeutic hope for cardiac regeneration and repair?

    PubMed

    Guan, Kaomei; Cheng, I-Fen; Baazm, Maryam

    2012-01-01

    Although the identification and characterization of human spermatogonial stem cells was reported nearly 50 years ago, great progress has been made only in the last few years. Spermatogonial stem cells attract a great deal of researchers' attention because of their unique characteristics, including the ability to be converted spontaneously into pluripotent germline stem cells with embryonic stem cell-like properties. Pluripotent stem cells are able to differentiate into any desired cell type in the body; therefore, they are the most promising cell source for organ regeneration. The advantages of pluripotent germline stem cells over other stem cells are that they maintain a high degree of DNA integrity and can resolve some ethical and immunological problems related to human embryonic stem cells. In this article we address the origin, characteristics and pluripotency of spermatogonial stem cells. Their contribution to stem cell-based organ regeneration therapy with special emphasis on cardiac regeneration and repair in the future is also discussed.

  3. Cardiac Adipose-Derived Stem Cells Exhibit High Differentiation Potential to Cardiovascular Cells in C57BL/6 Mice.

    PubMed

    Nagata, Hiroki; Ii, Masaaki; Kohbayashi, Eiko; Hoshiga, Masaaki; Hanafusa, Toshiaki; Asahi, Michio

    2016-02-01

    Adipose-derived stem cells (AdSCs) have recently been shown to differentiate into cardiovascular lineage cells. However, little is known about the fat tissue origin-dependent differences in AdSC function and differentiation potential. AdSC-rich cells were isolated from subcutaneous, visceral, cardiac (CA), and subscapular adipose tissue from mice and their characteristics analyzed. After four different AdSC types were cultured with specific differentiation medium, immunocytochemical analysis was performed for the assessment of differentiation into cardiovascular cells. We then examined the in vitro differentiation capacity and therapeutic potential of AdSCs in ischemic myocardium using a mouse myocardial infarction model. The cell density and proliferation activity of CA-derived AdSCs were significantly increased compared with the other adipose tissue-derived AdSCs. Immunocytochemistry showed that CA-derived AdSCs had the highest appearance rates of markers for endothelial cells, vascular smooth muscle cells, and cardiomyocytes among the AdSCs. Systemic transfusion of CA-derived AdSCs exhibited the highest cardiac functional recovery after myocardial infarction and the high frequency of the recruitment to ischemic myocardium. Moreover, long-term follow-up of the recruited CA-derived AdSCs frequently expressed cardiovascular cell markers compared with the other adipose tissue-derived AdSCs. Cardiac adipose tissue could be an ideal source for isolation of therapeutically effective AdSCs for cardiac regeneration in ischemic heart diseases. Significance: The present study found that cardiac adipose-derived stem cells have a high potential to differentiate into cardiovascular lineage cells (i.e., cardiomyocytes, endothelial cells, and vascular smooth muscle cells) compared with stem cells derived from other adipose tissue such as subcutaneous, visceral, and subscapular adipose tissue. Notably, only a small number of supracardiac adipose-derived stem cells that were

  4. Diffuse large B-cell lymphoma diagnosed by intracardiac echocardiography-guided cardiac tumor biopsy.

    PubMed

    Kamiya, Kiwamu; Sakakibara, Mamoru; Yamada, Shiro; Tan, Michinao; Furihata, Takaaki; Kubota, Kanako; Tsutsui, Hiroyuki

    2012-01-01

    A 44-year-old man presented with exertional dyspnea. Transthoracic echocardiography (TTE) revealed a large tumor protruding into the right atrium and extending into the left ventricle. Cardiac magnetic resonance imaging and contrast enhanced computed tomography also confirmed the intracardiac tumor detected by TTE. An endomyocardial biopsy was performed under the intracardiac echocardiography (ICE) guidance, and he was diagnosed to have diffuse large B-cell lymphoma following the histological analysis. ICE-guided cardiac tumor biopsy is expected to be a useful diagnostic strategy that can minimize the risk of procedural complications.

  5. Concise Review: Pluripotent Stem Cell-Derived Cardiac Cells, A Promising Cell Source for Therapy of Heart Failure: Where Do We Stand?

    PubMed

    Gouadon, Elodie; Moore-Morris, Thomas; Smit, Nicoline W; Chatenoud, Lucienne; Coronel, Ruben; Harding, Sian E; Jourdon, Philippe; Lambert, Virginie; Rucker-Martin, Catherine; Pucéat, Michel

    2016-01-01

    Heart failure is still a major cause of hospitalization and mortality in developed countries. Many clinical trials have tested the use of multipotent stem cells as a cardiac regenerative medicine. The benefit for the patients of this therapeutic intervention has remained limited. Herein, we review the pluripotent stem cells as a cell source for cardiac regeneration. We more specifically address the various challenges of this cell therapy approach. We question the cell delivery systems, the immune tolerance of allogenic cells, the potential proarrhythmic effects, various drug mediated interventions to facilitate cell grafting and, finally, we describe the pathological conditions that may benefit from such an innovative approach. As members of a transatlantic consortium of excellence of basic science researchers and clinicians, we propose some guidelines to be applied to cell types and modes of delivery in order to translate pluripotent stem cell cardiac derivatives into safe and effective clinical trials.

  6. Prolongation of survival of rat cardiac allografts by T cell vaccination.

    PubMed Central

    Shapira, O M; Mor, E; Reshef, T; Pfeffermann, R A; Cohen, I R

    1993-01-01

    Administration of attenuated, activated autoimmune T lymphocytes to syngeneic mice and rats has been shown to prevent or induce remission of experimental autoimmune diseases specific for the autoimmune T cells. The process has been termed "T cell vaccination." In a recent study, T cell vaccination was done using T cells sensitized to rat alloantigens. The procedure produced a significant reduction of the mixed lymphocyte reaction (MLR) against allogeneic cells. The reduction in MLR was not specific: Vaccination with T cells specific for stimulator cells of one allotype led to a reduced MLR stimulated by cells of another allotype. The present study was undertaken to examine whether T cell vaccination can induce tolerance to transplantation antigens in vivo. We used the model of heterotopic cardiac transplantation in rats. We now report that vaccinating rats with syngeneic, activated, alloantigen-primed T lymphocytes significantly prolonged survival of rat cardiac allografts. The effect of T cell vaccination was most evident when the T cells had been obtained from rats specifically sensitized against the donor rats: Brown-Norway (BN) allografts in control Wistar rats survived 8.5 +/- 0.4 d while BN allografts survived 29.2 +/- 7.1 d in Wistar rats that had been vaccinated with Wistar anti-BN cells. Vaccination of Wistar rats with Wistar anti-hooded T cells prolonged survival of BN heart allografts to a lesser but significant degree (13.0 +/- 1.1 d). Thus, T cell vaccination of recipients can prolong survival of allografts. PMID:8432846

  7. Myocardial infarction: stem cell transplantation for cardiac regeneration.

    PubMed

    Carvalho, Edmund; Verma, Paul; Hourigan, Kerry; Banerjee, Rinti

    2015-11-01

    It is estimated that by 2030, almost 23.6 million people will perish from cardiovascular disease, according to the WHO. The review discusses advances in stem cell therapy for myocardial infarction, including cell sources, methods of differentiation, expansion selection and their route of delivery. Skeletal muscle cells, hematopoietic cells and mesenchymal stem cells (MSCs) and embryonic stem cells (ESCs)-derived cardiomyocytes have advanced to the clinical stage, while induced pluripotent cells (iPSCs) are yet to be considered clinically. Delivery of cells to the sites of injury and their subsequent retention is a major issue. The development of supportive scaffold matrices to facilitate stem cell retention and differentiation are analyzed. The review outlines clinical translation of conjugate stem cell-based cellular therapeutics post-myocardial infarction.

  8. Beta Cell Mass Restoration in Alloxan-Diabetic Mice Treated with EGF and Gastrin.

    PubMed

    Song, Imane; Patel, Oelfah; Himpe, Eddy; Muller, Christo J F; Bouwens, Luc

    2015-01-01

    One week of treatment with EGF and gastrin (EGF/G) was shown to restore normoglycemia and to induce islet regeneration in mice treated with the diabetogenic agent alloxan. The mechanisms underlying this regeneration are not fully understood. We performed genetic lineage tracing experiments to evaluate the contribution of beta cell neogenesis in this model. One day after alloxan administration, mice received EGF/G treatment for one week. The treatment could not prevent the initial alloxan-induced beta cell mass destruction, however it did reverse glycemia to control levels within one day, suggesting improved peripheral glucose uptake. In vitro experiments with C2C12 cell line showed that EGF could stimulate glucose uptake with an efficacy comparable to that of insulin. Subsequently, EGF/G treatment stimulated a 3-fold increase in beta cell mass, which was partially driven by neogenesis and beta cell proliferation as assessed by beta cell lineage tracing and BrdU-labeling experiments, respectively. Acinar cell lineage tracing failed to show an important contribution of acinar cells to the newly formed beta cells. No appearance of transitional cells co-expressing insulin and glucagon, a hallmark for alpha-to-beta cell conversion, was found, suggesting that alpha cells did not significantly contribute to the regeneration. An important fraction of the beta cells significantly lost insulin positivity after alloxan administration, which was restored to normal after one week of EGF/G treatment. Alloxan-only mice showed more pronounced beta cell neogenesis and proliferation, even though beta cell mass remained significantly depleted, suggesting ongoing beta cell death in that group. After one week, macrophage infiltration was significantly reduced in EGF/G-treated group compared to the alloxan-only group. Our results suggest that EGF/G-induced beta cell regeneration in alloxan-diabetic mice is driven by beta cell neogenesis, proliferation and recovery of insulin. The

  9. Characterization of Cardiac-Resident Progenitor Cells Expressing High Aldehyde Dehydrogenase Activity

    PubMed Central

    Roehrich, Marc-Estienne; Spicher, Albert; Milano, Giuseppina; Vassalli, Giuseppe

    2013-01-01

    High aldehyde dehydrogenase (ALDH) activity has been associated with stem and progenitor cells in various tissues. Human cord blood and bone marrow ALDH-bright (ALDHbr) cells have displayed angiogenic activity in preclinical studies and have been shown to be safe in clinical trials in patients with ischemic cardiovascular disease. The presence of ALDHbr cells in the heart has not been evaluated so far. We have characterized ALDHbr cells isolated from mouse hearts. One percent of nonmyocytic cells from neonatal and adult hearts were ALDHbr. ALDHvery-br cells were more frequent in neonatal hearts than adult. ALDHbr cells were more frequent in atria than ventricles. Expression of ALDH1A1 isozyme transcripts was highest in ALDHvery-br cells, intermediate in ALDHbr cells, and lowest in ALDHdim cells. ALDH1A2 expression was highest in ALDHvery-br cells, intermediate in ALDHdim cells, and lowest in ALDHbr cells. ALDH1A3 and ALDH2 expression was detectable in ALDHvery-br and ALDHbr cells, unlike ALDHdim cells, albeit at lower levels compared with ALDH1A1 and ALDH1A2. Freshly isolated ALDHbr cells were enriched for cells expressing stem cell antigen-1, CD34, CD90, CD44, and CD106. ALDHbr cells, unlike ALDHdim cells, could be grown in culture for more than 40 passages. They expressed sarcomeric α-actinin and could be differentiated along multiple mesenchymal lineages. However, the proportion of ALDHbr cells declined with cell passage. In conclusion, the cardiac-derived ALDHbr population is enriched for progenitor cells that exhibit mesenchymal progenitor-like characteristics and can be expanded in culture. The regenerative potential of cardiac-derived ALDHbr cells remains to be evaluated. PMID:23484127

  10. Cardiac catheterization

    MedlinePlus

    Catheterization - cardiac; Heart catheterization; Angina - cardiac catheterization; CAD - cardiac catheterization; Coronary artery disease - cardiac catheterization; Heart valve - cardiac catheterization; Heart failure - ...

  11. Crosstalk of mesenchymal stem cells and macrophages promotes cardiac muscle repair.

    PubMed

    Wang, Mei; Zhang, Guoru; Wang, Yaling; Liu, Tao; Zhang, Yang; An, Yu; Li, Yongjun

    2015-01-01

    Transplantation of bone-marrow derived mesenchymal stem cells (MSCs) has potential therapeutic effects on cardiac muscle repair. However, the underlying mechanism remains not completely clarified. Here we show that transplantation of MSCs significantly increased local recruitment of macrophages to facilitate cardiac muscle repair. MSCs-induced recovery of cardiac function and attenuation of fibrosis after injury were all abolished by either impaired macrophage infiltration, or by MSCs depletion after macrophage recruitment. However, angiogenesis seemed to be only affected by depletion of macrophages, but not by depletion of MSCs, suggesting that macrophages are responsible for the augmented angiogenesis after MSCs transplantation, while MSCs do not directly contribute to angiogenesis in the functional cardiac repair. Moreover, high level of transforming growth factor β 1 (TGFβ1) was detected in macrophages and high level of BMP7 was detected in MSCs, suggesting that MSCs not only may recruit macrophages to enhance angiogenesis to promote regeneration, but also may secrete BMP7 to contradict the fibrogenic effect of TGFβ1 by macrophages. Our study thus sheds new insight on the interaction of MSCs and macrophages in a functional cardiac repair triggered by MSCs transplantation.

  12. Small RNA-directed epigenetic programming of embryonic stem cell cardiac differentiation

    PubMed Central

    Ghanbarian, Hossein; Wagner, Nicole; Michiels, Jean-François; Cuzin, François; Wagner, Kay-Dietrich; Rassoulzadegan, Minoo

    2017-01-01

    Microinjection of small noncoding RNAs in one-cell embryos was reported in several instances to result in transcriptional activation of target genes. To determine the molecular mechanisms involved and to explore whether such epigenetic regulations could play a role in early development, we used a cell culture system as close as possible to the embryonic state. We report efficient cardiac differentiation of embryonic stem (ES) cells induced by small non-coding RNAs with sequences of Cdk9, a key player in cardiomyocyte differentiation. Transfer of oligoribonucleotides representing parts of the Cdk9 mRNA into ES and mouse embryo fibroblast cultures resulted in upregulation of transcription. Dependency on Argonaute proteins and endogenous antisense transcripts indicated that the inducer oligoribonucleotides were processed by the RNAi machinery. Upregulation of Cdk9 expression resulted in increased efficiency of cardiac differentiation suggesting a potential tool for stem cell-based regenerative medicine. PMID:28165496

  13. Small RNA-directed epigenetic programming of embryonic stem cell cardiac differentiation.

    PubMed

    Ghanbarian, Hossein; Wagner, Nicole; Michiels, Jean-François; Cuzin, François; Wagner, Kay-Dietrich; Rassoulzadegan, Minoo

    2017-02-06

    Microinjection of small noncoding RNAs in one-cell embryos was reported in several instances to result in transcriptional activation of target genes. To determine the molecular mechanisms involved and to explore whether such epigenetic regulations could play a role in early development, we used a cell culture system as close as possible to the embryonic state. We report efficient cardiac differentiation of embryonic stem (ES) cells induced by small non-coding RNAs with sequences of Cdk9, a key player in cardiomyocyte differentiation. Transfer of oligoribonucleotides representing parts of the Cdk9 mRNA into ES and mouse embryo fibroblast cultures resulted in upregulation of transcription. Dependency on Argonaute proteins and endogenous antisense transcripts indicated that the inducer oligoribonucleotides were processed by the RNAi machinery. Upregulation of Cdk9 expression resulted in increased efficiency of cardiac differentiation suggesting a potential tool for stem cell-based regenerative medicine.

  14. Accumulation of Mitochondrial DNA Mutations Disrupts Cardiac Progenitor Cell Function and Reduces Survival.

    PubMed

    Orogo, Amabel M; Gonzalez, Eileen R; Kubli, Dieter A; Baptista, Igor L; Ong, Sang-Bing; Prolla, Tomas A; Sussman, Mark A; Murphy, Anne N; Gustafsson, Åsa B

    2015-09-04

    Transfer of cardiac progenitor cells (CPCs) improves cardiac function in heart failure patients. However, CPC function is reduced with age, limiting their regenerative potential. Aging is associated with numerous changes in cells including accumulation of mitochondrial DNA (mtDNA) mutations, but it is unknown how this impacts CPC function. Here, we demonstrate that acquisition of mtDNA mutations disrupts mitochondrial function, enhances mitophagy, and reduces the replicative and regenerative capacities of the CPCs. We show that activation of differentiation in CPCs is associated with expansion of the mitochondrial network and increased mitochondrial oxidative phosphorylation. Interestingly, mutant CPCs are deficient in mitochondrial respiration and rely on glycolysis for energy. In response to differentiation, these cells fail to activate mitochondrial respiration. This inability to meet the increased energy demand leads to activation of cell death. These findings demonstrate the consequences of accumulating mtDNA mutations and the importance of mtDNA integrity in CPC homeostasis and regenerative potential.

  15. Recent advances in cardiac regeneration: Stem cell, biomaterial and growth factors.

    PubMed

    Cheraghi, Mostafa; Namdari, Mehrdad; Negahdari, Babak; Eatemadi, Ali

    2017-03-01

    Myocardial infarction has been reported to be responsible for about 7.3 million deaths each year globally. Present treatments for myocardial infarction have been more palliative rather than curative. Over the past few years, stem cells have demonstrated its potency in regenerating damaged cardiac tissue, especially after myocardial infarction. However, limited short half-life of the protein and cell therapy and low transplanted cell survival rate as demonstrated via several clinical trials have lead to development of more potent and novel delivery systems like biomaterial delivery system and the use of various growth factors. In this review, we will be enumerating and discussing the recent advances in cardiac regeneration with focus on stem cell, biomaterial and growth factors.

  16. Effect of acute and prolonged alcohol administration on Mg(2+) homeostasis in cardiac cells.

    PubMed

    Romani, Andrea M P

    2015-05-01

    Alcoholic cardiomyopathy represents a major clinical complication in chronic alcoholics. Previous studies from our laboratory indicate that acute and chronic exposure of liver cells to ethanol results in a major loss of cellular Mg(2+) as a result of alcohol oxidation. We investigated whether exposure to ethanol induces a similar Mg(2+) loss in cardiac cells. The results indicate that chronic exposure to a 6% ethanol-containing diet depleted cardiac myocytes of >25% of their cellular Mg(2+) content. Acute ethanol exposure, instead, induced a time- and dose-dependent manner of Mg(2+) extrusion from perfused hearts and collagenase-dispersed cardiac ventricular myocytes. Pretreatment with chlormethiazole prevented ethanol-induced Mg(2+) loss to a large extent, suggesting a role of ethanol oxidation via cyP4502E1 in the process. Magnesium extrusion across the sarcolemma occurred via the amiloride-inhibited Na(+)/Mg(2+) exchanger. Taken together, our data indicate that Mg(2+) extrusion also occurs in cardiac cells exposed to ethanol as a result of alcohol metabolism by cyP4502E1. The extrusion, which is mediated by the Na(+)/Mg(2+) exchanger, only occurs at doses of ethanol ≥0.1%, and depends on ethanol-induced decline in cellular ATP. The significance of Mg(2+) extrusion for the onset of alcoholic cardiomyopathy remains to be elucidated.

  17. PD98059 Protects Brain against Cells Death Resulting from ROS/ERK Activation in a Cardiac Arrest Rat Model.

    PubMed

    Nguyen Thi, Phuong Anh; Chen, Meng-Hua; Li, Nuo; Zhuo, Xiao-Jun; Xie, Lu

    2016-01-01

    The clinical and experimental postcardiac arrest treatment has not reached therapeutic success. The present study investigated the effect of PD98059 (PD) in rats subjected to cardiac arrest (CA)/cardiopulmonary resuscitation (CPR). Experimental rats were divided randomly into 3 groups: sham, CA, and PD. The rats except for sham group were subjected to CA for 5 min followed by CPR operation. Once spontaneous circulation was restored, saline and PD were injected in CA and PD groups, respectively. The survival rates and neurologic deficit scores (NDS) were observed, and the following indices of brain tissue were evaluated: ROS, MDA, SOD, p-ERK1/2/ERK1/2, caspase-3, Bax, Bcl-2, TUNEL positive cells, and double fluorescent staining of p-ERK/TUNEL. Our results indicated that PD treatment significantly reduced apoptotic neurons and improved the survival rates and NDS. Moreover, PD markedly downregulated the ROS, MDA, p-ERK, and caspase-3, Bax and upregulated SOD and Bcl-2 levels. Double staining p-ERK/TUNEL in choroid plexus and cortex showed that cell death is dependent on ERK activation. The findings in present study demonstrated that PD provides neuroprotection via antioxidant activity and antiapoptosis in rats subjected to CA/CPR.

  18. Human Salivary Gland Stem Cells Functionally Restore Radiation Damaged Salivary Glands.

    PubMed

    Pringle, Sarah; Maimets, Martti; van der Zwaag, Marianne; Stokman, Monique A; van Gosliga, Djoke; Zwart, Erik; Witjes, Max J H; de Haan, Gerald; van Os, Ronald; Coppes, Rob P

    2016-03-01

    Adult stem cells are often touted as therapeutic agents in the regenerative medicine field, however data detailing both the engraftment and functional capabilities of solid tissue derived human adult epithelial stem cells is scarce. Here we show the isolation of adult human salivary gland (SG) stem/progenitor cells and demonstrate at the single cell level in vitro self-renewal and differentiation into multilineage organoids. We also show in vivo functionality, long-term engraftment, and functional restoration in a xenotransplantation model. Indeed, transplanted human salisphere-derived cells restored saliva production and greatly improved the regenerative potential of irradiated SGs. Further selection for c-Kit expression enriched for cells with enhanced regenerative potencies. Interestingly, interaction of transplanted cells with the recipient SG may also be involved in functional recovery. Thus, we show for the first time that salispheres cultured from human SGs contain stem/progenitor cells capable of self-renewal and differentiation and rescue of saliva production. Our study underpins the therapeutic promise of salisphere cell therapy for the treatment of xerostomia.

  19. Very small embryonic-like stem cells (VSELs)-a new promising candidate for use in cardiac regeneration.

    PubMed

    Zhang, Qian; Yang, Yue-Jin; Qian, Hai-Yan; Wang, Hong; Xu, Hui

    2011-01-01

    In recent years, stem cell-based therapy has been given increased attention in terms of its potential contribution to cardiac regeneration and repair, after acute myocardial infarction (AMI). The published studies have identified many kinds of stem cells with the ability to regenerate and repair damaged myocardium after AMI. These include embryonic stem cells (ESCs), mesenchymal stem cells (MSCs), multipotent adult progenitor cells, unrestricted somatic stem cells, etc. More recently, very small embryonic-like stem cells (VSELs) were identified from murine, as a population of very small CXCR4(+) Lin(-) CD45(-) cells and from human, as a population of very small CD34(+) CD133(+) CXCR4(+) Lin(-) CD45(-) cells. These cells exhibit beneficial effects on improving cardiac function and attenuating cardiac remodeling after AMI. However, the mechanisms underlying the benefits associated with VSELs therapy, in cardiac regeneration and repair, remain poorly understood. This review summarizes the current studies on cardiac repair with VSELs after AMI, and discusses the potential mechanisms and implications of these cells in cardiac repair.

  20. Single-Cell Expression Profiling Reveals a Dynamic State of Cardiac Precursor Cells in the Early Mouse Embryo.

    PubMed

    Kokkinopoulos, Ioannis; Ishida, Hidekazu; Saba, Rie; Ruchaya, Prashant; Cabrera, Claudia; Struebig, Monika; Barnes, Michael; Terry, Anna; Kaneko, Masahiro; Shintani, Yasunori; Coppen, Steven; Shiratori, Hidetaka; Ameen, Torath; Mein, Charles; Hamada, Hiroshi; Suzuki, Ken; Yashiro, Kenta

    2015-01-01

    In the early vertebrate embryo, cardiac progenitor/precursor cells (CPs) give rise to cardiac structures. Better understanding their biological character is critical to understand the heart development and to apply CPs for the clinical arena. However, our knowledge remains incomplete. With the use of single-cell expression profiling, we have now revealed rapid and dynamic changes in gene expression profiles of the embryonic CPs during the early phase after their segregation from the cardiac mesoderm. Progressively, the nascent mesodermal gene Mesp1 terminated, and Nkx2-5+/Tbx5+ population rapidly replaced the Tbx5low+ population as the expression of the cardiac genes Tbx5 and Nkx2-5 increased. At the Early Headfold stage, Tbx5-expressing CPs gradually showed a unique molecular signature with signs of cardiomyocyte differentiation. Lineage-tracing revealed a developmentally distinct characteristic of this population. They underwent progressive differentiation only towards the cardiomyocyte lineage corresponding to the first heart field rather than being maintained as a progenitor pool. More importantly, Tbx5 likely plays an important role in a transcriptional network to regulate the distinct character of the FHF via a positive feedback loop to activate the robust expression of Tbx5 in CPs. These data expands our knowledge on the behavior of CPs during the early phase of cardiac development, subsequently providing a platform for further study.

  1. Immunological barriers to stem-cell based cardiac repair.

    PubMed

    Karabekian, Zaruhi; Posnack, Nikki Gillum; Sarvazyan, Narine

    2011-06-01

    Repair of damaged myocardium with pluripotent stem cell derived cardiomyocytes is becoming increasingly more feasible. Developments in stem cell research emphasize the need to address the foreseeable problem of immune rejection following transplantation. Pluripotent stem cell (PSC) derived cardiomyocytes have unique immune characteristics, some of which are not advantageous for transplantation. Here we review the possible mechanisms of PSC-derived cardiomyocytes rejection, summarize the current knowledge pertaining to immunogenicity of such cells and describe the existing controversies. Myocardial graft rejection can be reduced by modifying PSCs prior to their differentiation into cardiomyocytes. Overall, this approach facilitates the development of universal donor stem cells suitable for the regeneration of many different tissue types.

  2. Galectin-1 Prevents Infection and Damage Induced by Trypanosoma cruzi on Cardiac Cells

    PubMed Central

    Benatar, Alejandro F.; García, Gabriela A.; Bua, Jacqeline; Cerliani, Juan P.; Postan, Miriam; Tasso, Laura M.; Scaglione, Jorge; Stupirski, Juan C.; Toscano, Marta A.

    2015-01-01

    Background Chronic Chagas cardiomyopathy caused by Trypanosoma cruzi is the result of a pathologic process starting during the acute phase of parasite infection. Among different factors, the specific recognition of glycan structures by glycan-binding proteins from the parasite or from the mammalian host cells may play a critical role in the evolution of the infection. Methodology and Principal Findings Here we investigated the contribution of galectin–1 (Gal–1), an endogenous glycan-binding protein abundantly expressed in human and mouse heart, to the pathophysiology of T. cruzi infection, particularly in the context of cardiac pathology. We found that exposure of HL–1 cardiac cells to Gal–1 reduced the percentage of infection by two different T. cruzi strains, Tulahuén (TcVI) and Brazil (TcI). In addition, Gal–1 prevented exposure of phosphatidylserine and early events in the apoptotic program by parasite infection on HL–1 cells. These effects were not mediated by direct interaction with the parasite surface, suggesting that Gal–1 may act through binding to host cells. Moreover, we also observed that T. cruzi infection altered the glycophenotype of cardiac cells, reducing binding of exogenous Gal–1 to the cell surface. Consistent with these data, Gal–1 deficient (Lgals1-/-) mice showed increased parasitemia, reduced signs of inflammation in heart and skeletal muscle tissues, and lower survival rates as compared to wild-type (WT) mice in response to intraperitoneal infection with T. cruzi Tulahuén strain. Conclusion/Significance Our results indicate that Gal–1 modulates T. cruzi infection of cardiac cells, highlighting the relevance of galectins and their ligands as regulators of host-parasite interactions. PMID:26451839

  3. Meta-Analyses of Human Cell-Based Cardiac Regeneration Therapies: Controversies in Meta-Analyses Results on Cardiac Cell-Based Regenerative Studies.

    PubMed

    Gyöngyösi, Mariann; Wojakowski, Wojciech; Navarese, Eliano P; Moye, Lemuel À

    2016-04-15

    In contrast to multiple publication-based meta-analyses involving clinical cardiac regeneration therapy in patients with recent myocardial infarction, a recently published meta-analysis based on individual patient data reported no effect of cell therapy on left ventricular function or clinical outcome. A comprehensive review of the data collection, statistics, and the overall principles of meta-analyses provides further clarification and explanation for this controversy. The advantages and pitfalls of different types of meta-analyses are reviewed here. Each meta-analysis approach has a place when pivotal clinical trials are lacking and sheds light on the magnitude of the treatment in a complex healthcare field.

  4. Management of mantle cell leukemia with cardiac involvement leading to cardiogenic shock.

    PubMed

    Furqan, Muhammad; Chen, Yamei; Akinleye, Akintunde; Sarungbam, Judy; Gass, Alan; Seiter, Karen; Liu, Delong

    2014-06-01

    Mantle cell lymphoma is an aggressive subtype of B cell non-Hodgkin lymphoma. It can progress to leukemic phase but frank leukemic picture at initial presentation is not common. Leukemic phase indicates advance stage of the disease and generally associated with extensive extra-nodal involvement. Pericardial invasion has been reported, however we could not find a report of myocardial infiltration by this disease since the appraisal of the term "mantle cell lymphoma" in 1992. Here we report a case of cardiac involvement by mantle cell leukemia leading to cardiogenic shock which complicates the treatment decisions.

  5. Targeting FXYD2 by cardiac glycosides potently blocks tumor growth in ovarian clear cell carcinoma

    PubMed Central

    Hsu, I-Ling; Chou, Cheng-Yang; Wu, Yi-Ying; Wu, Jia-En; Liang, Chen-Hsien; Tsai, Yao-Tsung; Ke, Jhen-Yu; Chen, Yuh-Ling; Hsu, Keng-Fu; Hong, Tse-Ming

    2016-01-01

    Ovarian clear cell carcinoma (OCCC) is an aggressive neoplasm with a high recurrence rate that frequently develops resistance to platinum-based chemotherapy. There are few prognostic biomarkers or targeted therapies exist for patients with OCCC. Here, we identified that FXYD2, the modulating subunit of Na+/K+-ATPases, was highly and specifically expressed in clinical OCCC tissues. The expression levels of FXYD2 were significantly higher in advanced-stage of OCCC and positively correlated with patients' prognoses. Silencing of FXYD2 expression in OCCC cells inhibited Na+/K+-ATPase enzyme activity and suppressed tumor growth via induction of autophagy-mediated cell death. We found that high FXYD2 expression in OCCC was transcriptionally regulated by the transcriptional factor HNF1B. Furthermore, up-regulation of FXYD2 expression significantly increased the sensitivity of OCCC cells to cardiac glycosides, the Na+/K+-ATPase inhibitors. Two cardiac glycosides, digoxin and digitoxin, had a great therapeutic efficacy in OCCC cells in vitro and in vivo. Taken together, our results demonstrate that FXYD2 is functionally upregulated in OCCC and may serve as a promising prognostic biomarker and therapeutic target of cardiac glycosides in OCCC. PMID:26910837

  6. (+)-Strebloside-Induced Cytotoxicity in Ovarian Cancer Cells Is Mediated through Cardiac Glycoside Signaling Networks.

    PubMed

    Chen, Wei-Lun; Ren, Yulin; Ren, Jinhong; Erxleben, Christian; Johnson, Michael E; Gentile, Saverio; Kinghorn, A Douglas; Swanson, Steven M; Burdette, Joanna E

    2017-03-24

    (+)-Strebloside, a cardiac glycoside isolated from the stem bark of Streblus asper collected in Vietnam, has shown some potential for further investigation as an antineoplastic agent. A mechanistic study using an in vitro assay and molecular docking analysis indicated that (+)-strebloside binds and inhibits Na(+)/K(+)-ATPase in a similar manner to digitoxin. Inhibition of growth of different high-grade serous ovarian cancer cells including OVCAR3, OVSAHO, Kuramochi, OVCAR4, OVCAR5, and OVCAR8 resulted from treatment with (+)-strebloside. Furthermore, this compound blocked cell cycle progression at the G2 phase and induced PARP cleavage, indicating apoptosis activation in OVCAR3 cells. (+)-Strebloside potently inhibited mutant p53 expression through the induction of ERK pathways and inhibited NF-κB activity in human ovarian cancer cells. However, in spite of its antitumor potential, the overall biological activity of (+)-strebloside must be regarded as being typical of better-known cardiac glycosides such as digoxin and ouabain. Further chemical alteration of cardiac glycosides might help to reduce negative side effects while increasing cancer cell cytotoxicity.

  7. Regulatory T cells improve nephrocalcinosis but not dystrophic cardiac calcinosis in DBA/2 mice.

    PubMed

    Kirsch, Alexander H; Smaczny, Nicole; Riegelbauer, Viktoria; Sedej, Simon; Hofmeister, Alexander; Stojakovic, Tatjana; Goessler, Walter; Brodmann, Marianne; Pilger, Ernst; Rosenkranz, Alexander R; Eller, Kathrin; Eller, Philipp

    2013-08-01

    Nephrocalcinosis is characterized by aberrant deposition of calcium in the kidneys and is seen in phosphate nephropathy, primary hyperparathyroidism, and distal renal tubular acidosis. To further evaluate the specific pathophysiologic role of T cells in ectopic calcification, we used DBA/2 mice that are prone to develop nephrocalcinosis and dystrophic cardiac calcinosis. Female DBA/2 mice were depleted of T cells (n = 10) or regulatory T cells (Tregs) (n = 15) using either an anti-CD3ɛ or an anti-CD25 monoclonal antibody and compared with isotype-treated controls (n = 9; n = 15), respectively. After this immunomodulation, the DBA/2 mice were given a high-phosphate diet for 9 days and the degree of calcification was assessed by microcomputed tomography. Successful depletion was confirmed by flow cytometry of splenocytes. In DBA/2 mice, the high-phosphate diet induced a phenotype of nephrocalcinosis and dystrophic cardiac calcinosis. T-cell depletion significantly increased renal calcification in microcomputed tomography (P = 0.022). Concordantly, Treg depletion significantly deteriorated acute phosphate nephropathy (P = 0.039) and was associated with a significantly increased mortality rate (P = 0.004). Immunomodulation had no impact on the amount of cardiac calcification. Semiquantitative histopathologic evaluations with Alizarin Red staining independently confirmed the respective radiologic measurements. In summary, our data suggest a pivotal role of T cells, particularly Tregs, in the progression of nephrocalcinosis and emphasize the fact that inflammation deteriorates the outcome in acute phosphate nephropathy.

  8. Caveolae protect endothelial cells from membrane rupture during increased cardiac output

    PubMed Central

    Cheng, Jade P.X.; Mendoza-Topaz, Carolina; Howard, Gillian; Chadwick, Jessica; Shvets, Elena; Cowburn, Andrew S.; Dunmore, Benjamin J.; Crosby, Alexi; Morrell, Nicholas W.

    2015-01-01

    Caveolae are strikingly abundant in endothelial cells, yet the physiological functions of caveolae in endothelium and other tissues remain incompletely understood. Previous studies suggest a mechanoprotective role, but whether this is relevant under the mechanical forces experienced by endothelial cells in vivo is unclear. In this study we have sought to determine whether endothelial caveolae disassemble under increased hemodynamic forces, and whether caveolae help prevent acute rupture of the plasma membrane under these conditions. Experiments in cultured cells established biochemical assays for disassembly of caveolar protein complexes, and assays for acute loss of plasma membrane integrity. In vivo, we demonstrate that caveolae in endothelial cells of the lung and cardiac muscle disassemble in response to acute increases in cardiac output. Electron microscopy and two-photon imaging reveal that the plasma membrane of microvascular endothelial cells in caveolin 1−/− mice is much more susceptible to acute rupture when cardiac output is increased. These data imply that mechanoprotection through disassembly of caveolae is important for endothelial function in vivo. PMID:26459598

  9. PlGF-MMP-9-expressing cells restore microcirculation and efficacy of cell therapy in aged dystrophic muscle.

    PubMed

    Gargioli, Cesare; Coletta, Marcello; De Grandis, Fabrizio; Cannata, Stefano M; Cossu, Giulio

    2008-09-01

    Sclerosis and reduced microvessel density characterize advanced stages of muscular dystrophy and hamper cell or gene delivery, precluding treatment of most individuals with Duchenne muscular dystrophy. Modified tendon fibroblasts expressing an angiogenic factor (placenta growth factor, PlGF) and a metalloproteinase (matrix metalloproteinase-9, MMP-9) are able to restore a vascular network and reduce collagen deposition, allowing efficient cell therapy in aged dystrophic mice. These data open the possibility of extending new therapies to currently untreatable individuals.

  10. A New Method to Stabilize C-Kit Expression in Reparative Cardiac Mesenchymal Cells

    PubMed Central

    Wysoczynski, Marcin; Dassanayaka, Sujith; Zafir, Ayesha; Ghafghazi, Shahab; Long, Bethany W.; Noble, Camille; DeMartino, Angelica M.; Brittian, Kenneth R.; Bolli, Roberto; Jones, Steven P.

    2016-01-01

    Cell therapy improves cardiac function. Few cells have been investigated more extensively or consistently shown to be more effective than c-kit sorted cells; however, c-kit expression is easily lost during passage. Here, our primary goal was to develop an improved method to isolate c-kitpos cells and maintain c-kit expression after passaging. Cardiac mesenchymal cells (CMCs) from wild-type mice were selected by polystyrene adherence properties. CMCs adhering within the first hours are referred to as rapidly adherent (RA); CMCs adhering subsequently are dubbed slowly adherent (SA). Both RA and SA CMCs were c-kit sorted. SA CMCs maintained significantly higher c-kit expression than RA cells; SA CMCs also had higher expression endothelial markers. We subsequently tested the relative efficacy of SA vs. RA CMCs in the setting of post-infarct adoptive transfer. Two days after coronary occlusion, vehicle, RA CMCs, or SA CMCs were delivered percutaneously with echocardiographic guidance. SA CMCs, but not RA CMCs, significantly improved cardiac function compared to vehicle treatment. Although the mechanism remains to be elucidated, the more pronounced endothelial phenotype of the SA CMCs coupled with the finding of increased vascular density suggest a potential pro-vasculogenic action. This new method of isolating CMCs better preserves c-kit expression during passage. SA CMCs, but not RA CMCs, were effective in reducing cardiac dysfunction. Although c-kit expression was maintained, it is unclear whether maintenance of c-kit expression per se was responsible for improved function, or whether the differential adherence property itself confers a reparative phenotype independently of c-kit. PMID:27536657

  11. Thymosin β4 coated nanofiber scaffolds for the repair of damaged cardiac tissue

    PubMed Central

    2014-01-01

    After a cardiac event, proper treatment and care of the damaged tissue is crucial in restoring optimal cardiac function and preventing future cardiac events. Recently, thymosin β4 has been found to play a vital role in cardiac cell health and development by regulating angiogenesis, inflammatory responses, and wound healing. We proposed that defined poly(ϵ-caprolactone) (PCL) nanoscaffolds coated with thymosin β4 could efficiently differentiate murine-derived cardiomyocytes into functioning cardiac tissue. PCL nanoscaffolds were developed through electrospinning technology, and subsequently coated with a thymosin β4 solution. Cardiomyocytes were seeded on coated and uncoated nanoscaffolds and observed for six days via fluorescent and electron microscopy. Our results demonstrated a robust growth and differentiation of cardiomyocytes on coated nanoscaffolds compared with uncoated, showing potential for nanoscaffold-mediated cardiac cell replacement in vivo after an MI or other cardiac event. PMID:24661328

  12. 3D printed complex tissue construct using stem cell-laden decellularized extracellular matrix bioinks for cardiac repair.

    PubMed

    Jang, Jinah; Park, Hun-Jun; Kim, Seok-Won; Kim, Heejin; Park, Ju Young; Na, Soo Jin; Kim, Hyeon Ji; Park, Moon Nyeo; Choi, Seung Hyun; Park, Sun Hwa; Kim, Sung Won; Kwon, Sang-Mo; Kim, Pum-Joon; Cho, Dong-Woo

    2017-01-01

    Stem cell therapy is a promising therapeutic method for the treatment of ischemic heart diseases; however, some challenges prohibit the efficacy after cell delivery due to hostile microenvironment of the injured myocardium. 3D printed pre-vascularized stem cell patch can enhance the therapeutic efficacy for cardiac repair through promotion of rapid vascularization after patch transplantation. In this study, stem cell-laden decellularized extracellular matrix bioinks are used in 3D printing of pre-vascularized and functional multi-material structures. The printed structure composed of spatial patterning of dual stem cells improves cell-to-cell interactions and differentiation capability and promotes functionality for tissue regeneration. The developed stem cell patch promoted strong vascularization and tissue matrix formation in vivo. The patterned patch exhibited enhanced cardiac functions, reduced cardiac hypertrophy and fibrosis, increased migration from patch to the infarct area, neo-muscle and capillary formation along with improvements in cardiac functions. Therefore, pre-vascularized stem cell patch provides cardiac niche-like microenvironment, resulting in beneficial effects on cardiac repair.

  13. Intracellular Energetic Units regulate metabolism in cardiac cells.

    PubMed

    Saks, Valdur; Kuznetsov, Andrey V; Gonzalez-Granillo, Marcela; Tepp, Kersti; Timohhina, Natalja; Karu-Varikmaa, Minna; Kaambre, Tuuli; Dos Santos, Pierre; Boucher, François; Guzun, Rita

    2012-02-01

    This review describes developments in historical perspective as well as recent results of investigations of cellular mechanisms of regulation of energy fluxes and mitochondrial respiration by cardiac work - the metabolic aspect of the Frank-Starling law of the heart. A Systems Biology solution to this problem needs the integration of physiological and biochemical mechanisms that take into account intracellular interactions of mitochondria with other cellular systems, in particular with cytoskeleton components. Recent data show that different tubulin isotypes are involved in the regular arrangement exhibited by mitochondria and ATP-consuming systems into Intracellular Energetic Units (ICEUs). Beta II tubulin association with the mitochondrial outer membrane, when co-expressed with mitochondrial creatine kinase (MtCK) specifically limits the permeability of voltage-dependent anion channel for adenine nucleotides. In the MtCK reaction this interaction changes the regulatory kinetics of respiration through a decrease in the affinity for adenine nucleotides and an increase in the affinity for creatine. Metabolic Control Analysis of the coupled MtCK-ATP Synthasome in permeabilized cardiomyocytes showed a significant increase in flux control by steps involved in ADP recycling. Mathematical modeling of compartmentalized energy transfer represented by ICEUs shows that cyclic changes in local ADP, Pi, phosphocreatine and creatine concentrations during contraction cycle represent effective metabolic feedback signals when amplified in the coupled non-equilibrium MtCK-ATP Synthasome reactions in mitochondria. This mechanism explains the regulation of respiration on beat to beat basis during workload changes under conditions of metabolic stability. This article is part of a Special Issue entitled "Local Signaling in Myocytes."

  14. Soluble CD80 restores T cell activation and overcomes tumor cell programmed death ligand 1-mediated immune suppression.

    PubMed

    Haile, Samuel T; Dalal, Sonia P; Clements, Virginia; Tamada, Koji; Ostrand-Rosenberg, Suzanne

    2013-09-01

    Many tumor cells escape anti-tumor immunity through their expression of programmed death ligand-1 (PDL1 or B7-H1), which interacts with T cell-expressed PD1 and results in T cell apoptosis. We previously reported that transfection of human tumor cells with a membrane-bound form of the human costimulatory molecule CD80 prevented PD1 binding and restored T cell activation. We now report that a membrane-bound form of murine CD80 similarly reduces PDL1-PD1-mediated suppression by mouse tumor cells and that a soluble protein consisting of the extracellular domains of human or mouse CD80 fused to the Fc domain of IgG1 (CD80-Fc) overcomes PDL1-mediated suppression by human and mouse tumor cells, respectively. T cell activation experiments with human and mouse tumor cells indicate that CD80-Fc facilitates T cell activation by binding to PDL1 to inhibit PDL1-PD1 interactions and by costimulating through CD28. CD80-Fc is more effective in preventing PD1-PDL1-mediated suppression and restoring T cell activation compared with treatment with mAb to either PD1 or PDL1. These studies identify CD80-Fc as an alternative and potentially more efficacious therapeutic agent for overcoming PDL1-induced immune suppression and facilitating tumor-specific immunity.

  15. Hiding inside? Intracellular expression of non-glycosylated c-kit protein in cardiac progenitor cells.

    PubMed

    Shi, Huilin; Drummond, Christopher A; Fan, Xiaoming; Haller, Steven T; Liu, Jiang; Malhotra, Deepak; Tian, Jiang

    2016-05-01

    Cardiac progenitor cells including c-kit(+) cells and cardiosphere-derived cells (CDCs) play important roles in cardiac repair and regeneration. CDCs were reported to contain only small subpopulations of c-kit(+) cells and recent publications suggested that depletion of the c-kit(+) subpopulation of cells has no effect on regenerative properties of CDCs. However, our current study showed that the vast majority of CDCs from murine heart actually express c-kit, albeit, in an intracellular and non-glycosylated form. Immunostaining and flow cytometry showed that the fluorescent signal indicative of c-kit immunostaining significantly increased when cell membranes were permeabilized. Western blots further demonstrated that glycosylation of c-kit was increased during endothelial differentiation in a time dependent manner. Glycosylation inhibition by 1-deoxymannojirimycin hydrochloride (1-DMM) blocked c-kit glycosylation and reduced expression of endothelial cell markers such as Flk-1 and CD31 during differentiation. Pretreatment of these cells with a c-kit kinase inhibitor (imatinib mesylate) also attenuated Flk-1 and CD31 expression. These results suggest that c-kit glycosylation and its kinase activity are likely needed for these cells to differentiate into an endothelial lineage. In vivo, we found that intracellular c-kit expressing cells are located in the wall of cardiac blood vessels in mice subjected to myocardial infarction. In summary, our work demonstrated for the first time that c-kit is not only expressed in CDCs but may also directly participate in CDC differentiation into an endothelial lineage.

  16. Shrink-induced biomimetic wrinkled substrates for functional cardiac cell alignment and culture.

    PubMed

    Mendoza, Nicole; Tu, Roger; Chen, Aaron; Lee, Eugene; Khine, Michelle

    2014-01-01

    The anisotropic alignment of cardiomyocytes in native myocardium tissue is a functional feature that is absent in traditional in vitro cardiac cell culture. Microenvironmental factors cue structural organization of the myocardium, which promotes the mechanical contractile properties and electrophysiological patterns seen in mature cardiomyocytes. Current nano- and microfabrication techniques, such as photolithography, generate simplified cell culture topographies that are not truly representative of the multifaceted and multi-scale fibrils of the cardiac extracellular matrix. In addition, such technologies are costly and require a clean room for fabrication. This chapter offers an easy, fast, robust, and inexpensive fabrication of biomimetic multi-scale wrinkled surfaces through the process of plasma treating and shrinking prestressed thermoplastic. Additionally, this chapter includes techniques for culturing stem cells and their cardiac derivatives on these substrates. Importantly, this wrinkled cell culture platform is compatible with both fluorescence and bright-field imaging; real-time physiological monitoring of CM action potential propagation and contraction properties can elucidate cardiotoxicity drug effects.

  17. Perioperative management of sickle cell disease in paediatric cardiac surgery.

    PubMed

    Bhatt, K; Cherian, S; Agarwal, R; Jose, S; Cherian, K M

    2007-10-01

    In sickle cell disease, cardiopulmonary bypass may induce red cell sickling. Partial exchange transfusion reduces the circulating haemoglobin S level. We report the management of a child with sickle cell disease who required surgical closure of a ventricular septal defect. Preoperative exchange transfusion of 50% of the total blood volume was performed with fresh packed red cells over three days. Further exchange transfusion was performed as cardiopulmonary bypass commenced. The haemoglobin S level was reduced from 76% to 37%. The blood removed from the patient during the exchanges was processed allowing storage and re-infusion of the patient's plasma and platelets. Combined preoperative and intraoperative exchange transfusions, instead of a single stage 50% volume exchange, was effective and potentially avoids larger haemodynamic effects. Cardiopulmonary bypass was conducted at normothermia and cold cardioplegia was avoided (fibrillatory arrest was used during the surgical repair).

  18. Foetal bovine serum-derived exosomes affect yield and phenotype of human cardiac progenitor cell culture

    PubMed Central

    Angelini, Francesco; Ionta, Vittoria; Rossi, Fabrizio; Miraldi, Fabio; Messina, Elisa; Giacomello, Alessandro

    2016-01-01

    Introduction: Cardiac progenitor cells (CPCs) represent a powerful tool in cardiac regenerative medicine. Pre-clinical studies suggest that most of the beneficial effects promoted by the injected cells are due to their paracrine activity exerted on endogenous cells and tissue. Exosomes are candidate mediators of this paracrine effects. According to their potential, many researchers have focused on characterizing exosomes derived from specific cell types, but, up until now, only few studies have analyzed the possible in vitro effects of bovine serum-derived exosomes on cell proliferation or differentiation. Methods: The aim of this study was to analyse, from a qualitative and quantitative point of view, the in vitro effects of bovine serum exosomes on human CPCs cultured either as cardiospheres or as monolayers of cardiosphere-forming cells. Results: Effects on proliferation, yield and molecular patterning were detected. We show, for the first time, that exogenous bovine exosomes support the proliferation and migration of human cardiosphere-forming cells, and that their depletion affects cardiospheres formation, in terms of size, yield and extra-cellular matrix production. Conclusion: These results stress the importance of considering differential biological effects of exogenous cell culture supplements on the final phenotype of primary human cell cultures. PMID:27340620

  19. Micro-perfusion for cardiac tissue engineering: development of a bench-top system for the culture of primary cardiac cells.

    PubMed

    Khait, Luda; Hecker, Louise; Radnoti, Desmond; Birla, Ravi K

    2008-05-01

    Tissue-engineered constructs have high metabolic requirements during in vitro culture necessitating the development of micro-perfusion systems to maintain high functional performance. In this study, we describe the design, fabrication, and testing of a novel micro-perfusion system to support the culture of primary cardiac cells. Our system consists of a micro-incubator with independent stages for 35-mm tissue culture plates with inflow/outflow manifolds for fluid delivery and aspiration. A peristaltic pump is utilized for fluid delivery and vacuum for fluid aspiration. Oxygen saturation, pH, and temperature are regulated for the media while temperature is regulated within the micro-incubator, fluid reservoir, and oxygenation chamber. Validation of the perfusion system was carried out using primary cardiac myocytes, isolated from 2- to 3-day-old neonatal rat hearts, plated on collagen-coated tissue culture plates. Two million cells/plate were used and the perfusion system was run for 1 h (without the need for a cell culture incubator) while controls were maintained in a standard cell culture incubator. We evaluated the cell viability, cell adhesion, total protein, total RNA, and changes in the expression of SERCA2 and phospholamban using RT-PCR, with N = 6 for each group. We found that there was no significant change in any variable during the 1-h run in the perfusion system. These studies served to demonstrate the compatibility of the perfusion system to support short-term culture of primary cardiac cells.

  20. Imaging cardiac stem cell therapy: translations to human clinical studies.

    PubMed

    Zhang, Wendy Y; Ebert, Antje D; Narula, Jagat; Wu, Joseph C

    2011-08-01

    Stem cell therapy promises to open exciting new options in the treatment of cardiovascular diseases. Although feasible and clinically safe, the in vivo behavior and integration of stem cell transplants still remain largely unknown. Thus, the development of innovative non-invasive imaging techniques capable of effectively tracking such therapy in vivo is vital for a more in-depth investigation into future clinical applications. Such imaging modalities will not only generate further insight into the mechanisms behind stem cell-based therapy, but also address some major concerns associated with translational cardiovascular stem cell therapy. In the present review, we summarize the principles underlying three major stem cell tracking methods: (1) radioactive labeling for positron emission tomography (PET) and single photon emission computed tomography (SPECT) imaging, (2) iron particle labeling for magnetic resonance imaging (MRI), and (3) reporter gene labeling for bioluminescence, fluorescence, MRI, SPECT, and PET imaging. We then discuss recent clinical studies that have utilized these modalities to gain biological insights into stem cell fate.

  1. Cardiac tamponade and paroxysmal third-degree atrioventricular block revealing a primary cardiac non-Hodgkin large B-cell lymphoma of the right ventricle: a case report

    PubMed Central

    2011-01-01

    Introduction Primary cardiac lymphoma is rare. Case Presentation We report the case of a 64-year-old non-immunodeficient Caucasian man, with cardiac tamponade and paroxysmal third-degree atrioventricular block. Echocardiography revealed the presence of a large pericardial effusion with signs of tamponade and a right ventricular mass was suspected. Scanner investigations clarified the sites, extension and anatomic details of myocardial and pericardial infiltration. Surgical resection was performed due to the rapid impairment of his cardiac function. Analysis of the pericardial fluid and histology confirmed the diagnosis of non-Hodgkin large B-cell lymphoma. He was treated with chemotherapy. Conclusion The prognosis remains poor for this type of tumor due to delays in diagnosis and the importance of the site of disease. PMID:21892927

  2. Obstructive Primary Cardiac T-Cell Lymphoma: A Case Report from Senegal

    PubMed Central

    Sarr, Simon Antoine; Gaye, Abdou Majib; Aw, Fatou; de Dieu Nzambaza, Jean; Bodian, Malick; Babaka, Kana; Ndiaye, Mouhamadou Bamba; Kane, Adama; Diao, Maboury; Ba, Serigne Abdou

    2017-01-01

    Patient: Female, 32 Final Diagnosis: Obstructive primary cardiac T-cell lymphoma Symptoms: Right heart failure Medication: — Clinical Procedure: None Specialty: Cardiology Objective: Rare disease Background: Cardiac lymphoma is a rare entity, defined by the non-extra cardiac location at diagnosis. Case Report: Our patient was a 32-year-old female with no particular medical history, who presented with right heart failure with recurrent ascites and pleural effusion. There was a progressive worsening exertional dyspnea. On admission, examination revealed an irregular tachycardia at 170 beats per minute (bpm) and congestive heart failure. The electrocardiogram scored full tachyarrhythmia by atrial fibrillation with an average ventricular rate of 179 cycles per minute. Doppler echocardiography showed dilatation and systolic dysfunction of the left ventricle. There were dilated atria. We noted a large mass in the right atrium, which was less mobile, heterogeneous, integral with the wall, and filling three quarters of the cavity. It clogged the tricuspid valve in diastole. CT scan showed a tissue process enhanced after contrast injection, occupying the predominant cavities in the right atrium and filling it. Its borders were irregular. The lesion was extended to the posterior mediastinum, in front of the vertebral axis. In addition, there was a thrombosis of the jugular vein and the inferior vena cava. There was no other tumor site noted. The patient died after presenting with cardiovascular shock associated with refractory right heart failure. Pathology examination confirmed T-cell lymphoma. Conclusions: The primitive cardiac lymphoma is an entity of intra-cardiac masses. It is therefore to be considered even if the diagnosis is challenging. PMID:28316327

  3. Restorative effect of hair follicular dermal cells on injured human hair follicles in a mouse model.

    PubMed

    Yamao, Mikaru; Inamatsu, Mutsumi; Okada, Taro; Ogawa, Yuko; Ishida, Yuji; Tateno, Chise; Yoshizato, Katsutoshi

    2015-03-01

    No model is available for examining whether in vivo-damaged human hair follicles (hu-HFs) are rescued by transplanting cultured hu-HF dermal cells (dermal papilla and dermal sheath cells). Such a model might be valuable for examining whether in vivo-damaged hu-HFs such as miniaturized hu-HFs in androgenic alopecia are improvable by auto-transplanting hu-HF dermal cells. In this study, we first developed mice with humanized skin composed of hu-keratinocytes and hu-dermal fibroblasts. Then, a 'humanized scalp model mouse' was generated by transplanting hu-scalp HFs into the humanized skin. To demonstrate the usability of the model, the lower halves of the hu-HFs in the model were amputated in situ, and cultured hu-HF dermal cells were injected around the amputated area. The results demonstrated that the transplanted cells contributed to the restoration of the damaged HFs. This model could be used to explore clinically effective technologies for hair restoration therapy by autologous cell transplantation.

  4. Stem cells and cardiac repair: a critical analysis.

    PubMed

    Dinsmore, Jonathan H; Dib, Nabil

    2008-03-01

    Utilizing stem cells to repair the damaged heart has seen an intense amount of activity over the last 5 years or so. There are currently multiple clinical studies in progress to test the efficacy of various different cell therapy approaches for the repair of damaged myocardium that were only just beginning to be tested in preclinical animal studies a few years earlier. This rapid transition from preclinical to clinical testing is striking and is not typical of the customary timeframe for the progress of a therapy from bench-to-bedside. Doubtless, there will be many more trials to follow in the upcoming years. With the plethora of trials and cell alternatives, there has come not only great enthusiasm for the potential of the therapy, but also great confusion about what has been achieved. Cell therapy has the potential to do what no drug can: regenerate and replace damaged tissue with healthy tissue. Drugs may be effective at slowing the progression of heart failure, but none can stop or reverse the process. However, tissue repair is not a simple process, although the idea on its surface is quite simple. Understanding cells, the signals that they respond to, and the keys to appropriate survival and tissue formation are orders of magnitude more complicated than understanding the pathways targeted by most drugs. Drugs and their metabolites can be monitored, quantified, and their effects correlated to circulating levels in the body. Not so for most cell therapies. It is quite difficult to measure cell survival except through ex vivo techniques like histological analysis of the target organ. This makes the emphasis on preclinical research all the more important because it is only in the animal studies that research has the opportunity to readily harvest the target tissues and perform the detailed analyses of what has happened with the cells. This need for detailed and usually time-intensive research in animal studies stands in contrast to the rapidity with which

  5. Mesodermal iPSC–derived progenitor cells functionally regenerate cardiac and skeletal muscle

    PubMed Central

    Quattrocelli, Mattia; Swinnen, Melissa; Giacomazzi, Giorgia; Camps, Jordi; Barthélemy, Ines; Ceccarelli, Gabriele; Caluwé, Ellen; Grosemans, Hanne; Thorrez, Lieven; Pelizzo, Gloria; Muijtjens, Manja; Verfaillie, Catherine M.; Blot, Stephane; Janssens, Stefan; Sampaolesi, Maurilio

    2015-01-01

    Conditions such as muscular dystrophies (MDs) that affect both cardiac and skeletal muscles would benefit from therapeutic strategies that enable regeneration of both of these striated muscle types. Protocols have been developed to promote induced pluripotent stem cells (iPSCs) to differentiate toward cardiac or skeletal muscle; however, there are currently no strategies to simultaneously target both muscle types. Tissues exhibit specific epigenetic alterations; therefore, source-related lineage biases have the potential to improve iPSC-driven multilineage differentiation. Here, we determined that differential myogenic propensity influences the commitment of isogenic iPSCs and a specifically isolated pool of mesodermal iPSC-derived progenitors (MiPs) toward the striated muscle lineages. Differential myogenic propensity did not influence pluripotency, but did selectively enhance chimerism of MiP-derived tissue in both fetal and adult skeletal muscle. When injected into dystrophic mice, MiPs engrafted and repaired both skeletal and cardiac muscle, reducing functional defects. Similarly, engraftment into dystrophic mice of canine MiPs from dystrophic dogs that had undergone TALEN-mediated correction of the MD-associated mutation also resulted in functional striatal muscle regeneration. Moreover, human MiPs exhibited the same capacity for the dual differentiation observed in murine and canine MiPs. The findings of this study suggest that MiPs should be further explored for combined therapy of cardiac and skeletal muscles. PMID:26571398

  6. A global sensitivity tool for cardiac cell modeling: Application to ionic current balance and hypertrophic signaling.

    PubMed

    Sher, Anna A; Cooling, Michael T; Bethwaite, Blair; Tan, Jefferson; Peachey, Tom; Enticott, Colin; Garic, Slavisa; Gavaghan, David J; Noble, Denis; Abramson, David; Crampin, Edmund J

    2010-01-01

    Cardiovascular diseases are the major cause of death in the developed countries. Identifying key cellular processes involved in generation of the electrical signal and in regulation of signal transduction pathways is essential for unraveling the underlying mechanisms of heart rhythm behavior. Computational cardiac models provide important insights into cardiovascular function and disease. Sensitivity analysis presents a key tool for exploring the large parameter space of such models, in order to determine the key factors determining and controlling the underlying physiological processes. We developed a new global sensitivity analysis tool which implements the Morris method, a global sensitivity screening algorithm, onto a Nimrod platform, which is a distributed resources software toolkit. The newly developed tool has been validated using the model of IP3-calcineurin signal transduction pathway model which has 30 parameters. The key driving factors of the IP3 transient behaviour have been calculated and confirmed to agree with previously published data. We next demonstrated the use of this method as an assessment tool for characterizing the structure of cardiac ionic models. In three latest human ventricular myocyte models, we examined the contribution of transmembrane currents to the shape of the electrical signal (i.e. on the action potential duration). The resulting profiles of the ionic current balance demonstrated the highly nonlinear nature of cardiac ionic models and identified key players in different models. Such profiling suggests new avenues for development of methodologies to predict drug action effects in cardiac cells.

  7. Osseous metastases from renal cell carcinoma: embolization and surgery for restoration of function. Work in progress

    SciTech Connect

    Rowe, D.M.; Becker, G.J.; Rabe, F.E.; Holden, R.W.; Richmond, B.D.; Wass, J.L.; Sequeira, F.W.

    1984-03-01

    Five patients underwent preoperative embolization of osseous metastases from renal cell carcinoma. The group consisted of four men and one woman who ranged in age from 46 to 79 years. The lesions were located in the pubic ramus and acetabulum, proximal femur, femoral midshaft, proximal humerus, and proximal tibia. All embolizations were performed within 24 hours of surgery. The internal fixation and tumor curettage was accomplished with estimated perioperative blood loss ranging from 10 ml to 1,250 ml. All patients had significant restoration of function following surgery. The authors suggest that preoperative embolization is an important and efficacious adjunct in the management of hypervascular renal cell osseous metastases.

  8. Bone Marrow Mononuclear Cell Transplantation Restores Inflammatory Balance of Cytokines after ST Segment Elevation Myocardial Infarction

    PubMed Central

    Alestalo, Kirsi; Miettinen, Johanna A.; Vuolteenaho, Olli; Huikuri, Heikki; Lehenkari, Petri

    2015-01-01

    Background Acute myocardial infarction (AMI) launches an inflammatory response and a repair process to compensate cardiac function. During this process, the balance between proinflammatory and anti-inflammatory cytokines is important for optimal cardiac repair. Stem cell transplantation after AMI improves tissue repair and increases the ventricular ejection fraction. Here, we studied in detail the acute effect of bone marrow mononuclear cell (BMMNC) transplantation on proinflammatory and anti-inflammatory cytokines in patients with ST segment elevation myocardial infarction (STEMI). Methods Patients with STEMI treated with thrombolysis followed by percutaneous coronary intervention (PCI) were randomly assigned to receive either BMMNC or saline as an intracoronary injection. Cardiac function was evaluated by left ventricle angiogram during the PCI and again after 6 months. The concentrations of 27 cytokines were measured from plasma samples up to 4 days after the PCI and the intracoronary injection. Results Twenty-six patients (control group, n = 12; BMMNC group, n = 14) from the previously reported FINCELL study (n = 80) were included to this study. At day 2, the change in the proinflammatory cytokines correlated with the change in the anti-inflammatory cytokines in both groups (Kendall’s tau, control 0.6; BMMNC 0.7). At day 4, the correlation had completely disappeared in the control group but was preserved in the BMMNC group (Kendall’s tau, control 0.3; BMMNC 0.7). Conclusions BMMNC transplantation is associated with preserved balance between pro- and anti-inflammatory cytokines after STEMI in PCI-treated patients. This may partly explain the favorable effect of stem cell transplantation after AMI. PMID:26690350

  9. HDLs protect pancreatic β-cells against ER stress by restoring protein folding and trafficking.

    PubMed

    Pétremand, Jannick; Puyal, Julien; Chatton, Jean-Yves; Duprez, Jessica; Allagnat, Florent; Frias, Miguel; James, Richard W; Waeber, Gérard; Jonas, Jean-Christophe; Widmann, Christian

    2012-05-01

    Endoplasmic reticulum (ER) homeostasis alteration contributes to pancreatic β-cell dysfunction and death and favors the development of diabetes. In this study, we demonstrate that HDLs protect β-cells against ER stress induced by thapsigargin, cyclopiazonic acid, palmitate, insulin overexpression, and high glucose concentrations. ER stress marker induction and ER morphology disruption mediated by these stimuli were inhibited by HDLs. Using a temperature-sensitive viral glycoprotein folding mutant, we show that HDLs correct impaired protein trafficking and folding induced by thapsigargin and palmitate. The ability of HDLs to protect β-cells against ER stress was inhibited by brefeldin A, an ER to Golgi trafficking blocker. These results indicate that HDLs restore ER homeostasis in response to ER stress, which is required for their ability to promote β-cell survival. This study identifies a cellular mechanism mediating the beneficial effect of HDLs on β-cells against ER stress-inducing factors.

  10. HDLs Protect Pancreatic β-Cells Against ER Stress by Restoring Protein Folding and Trafficking

    PubMed Central

    Pétremand, Jannick; Puyal, Julien; Chatton, Jean-Yves; Duprez, Jessica; Allagnat, Florent; Frias, Miguel; James, Richard W.; Waeber, Gérard; Jonas, Jean-Christophe; Widmann, Christian

    2012-01-01

    Endoplasmic reticulum (ER) homeostasis alteration contributes to pancreatic β-cell dysfunction and death and favors the development of diabetes. In this study, we demonstrate that HDLs protect β-cells against ER stress induced by thapsigargin, cyclopiazonic acid, palmitate, insulin overexpression, and high glucose concentrations. ER stress marker induction and ER morphology disruption mediated by these stimuli were inhibited by HDLs. Using a temperature-sensitive viral glycoprotein folding mutant, we show that HDLs correct impaired protein trafficking and folding induced by thapsigargin and palmitate. The ability of HDLs to protect β-cells against ER stress was inhibited by brefeldin A, an ER to Golgi trafficking blocker. These results indicate that HDLs restore ER homeostasis in response to ER stress, which is required for their ability to promote β-cell survival. This study identifies a cellular mechanism mediating the beneficial effect of HDLs on β-cells against ER stress-inducing factors. PMID:22399686

  11. Restoring ciliary function to differentiated Primary Ciliary Dyskinesia cells with a lentiviral vector

    PubMed Central

    Ostrowski, Lawrence E; Yin, Weining; Patel, Manij; Sechelski, John; Rogers, Troy; Burns, Kimberlie; Grubb, Barbara R; Olsen, John C

    2014-01-01

    Primary ciliary dyskinesia is a genetically heterogeneous autosomal recessive disease in which mutations disrupt ciliary function, leading to impaired mucociliary clearance and life-long lung disease. Mouse tracheal cells with a targeted deletion in the axonemal dynein intermediated chain gene Dnaic1 differentiate normally in culture but lack ciliary activity. Gene transfer to undifferentiated cultures of mouse Dnaic1−/− cells with a lentiviral vector pseudotyped with avian influenza hemagglutinin restored Dnaic1 expression and ciliary activity. Importantly, apical treatment of well-differentiated cultures of mouse Dnaic1−/− with lentiviral vector also restored ciliary activity, demonstrating successful gene transfer from the apical surface. Treatment of Dnaic1flox/flox mice expressing an estrogen responsive Cre recombinase with different doses of tamoxifen indicated that restoration of ~20% of ciliary activity may be sufficient to prevent the development of rhinosinusitis. However, while administration of a β-galactosidase expressing vector to control mice demonstrated efficient gene transfer to the nasal epithelium, treatment of Dnaic1−/− mice resulted in a low level of gene transfer, demonstrating that the severe rhinitis present in these animals impedes gene transfer. The results demonstrate that gene replacement therapy may be a viable treatment option for primary ciliary dyskinesia, but further improvements in the efficiency of gene transfer are necessary. PMID:24451115

  12. Human induced pluripotent stem cell-derived beating cardiac tissues on paper.

    PubMed

    Wang, Li; Xu, Cong; Zhu, Yujuan; Yu, Yue; Sun, Ning; Zhang, Xiaoqing; Feng, Ke; Qin, Jianhua

    2015-11-21

    There is a growing interest in using paper as a biomaterial scaffold for cell-based applications. In this study, we made the first attempt to fabricate a paper-based array for the culture, proliferation, and direct differentiation of human induced pluripotent stem cells (hiPSCs) into functional beating cardiac tissues and create "a beating heart on paper." This array was simply constructed by binding a cured multi-well polydimethylsiloxane (PDMS) mold with common, commercially available paper substrates. Three types of paper material (print paper, chromatography paper and nitrocellulose membrane) were tested for adhesion, proliferation and differentiation of human-derived iPSCs. We found that hiPSCs grew well on these paper substrates, presenting a three-dimensional (3D)-like morphology with a pluripotent property. The direct differentiation of human iPSCs into functional cardiac tissues on paper was also achieved using our modified differentiation approach. The cardiac tissue retained its functional activities on the coated print paper and chromatography paper with a beating frequency of 40-70 beats per min for up to three months. Interestingly, human iPSCs could be differentiated into retinal pigment epithelium on nitrocellulose membrane under the conditions of cardiac-specific induction, indicating the potential roles of material properties and mechanical cues that are involved in regulating stem cell differentiation. Taken together, these results suggest that different grades of paper could offer great opportunities as bioactive, low-cost, and 3D in vitro platforms for stem cell-based high-throughput drug testing at the tissue/organ level and for tissue engineering applications.

  13. Cardiac Migration of Endogenous Mesenchymal Stromal Cells in Patients with Inflammatory Cardiomyopathy

    PubMed Central

    Schmidt-Lucke, Caroline; Escher, Felicitas; Van Linthout, Sophie; Kühl, Uwe; Miteva, Kapka; Schultheiss, Heinz-Peter; Tschöpe, Carsten

    2015-01-01

    Introduction. Mesenchymal stromal cells (MSC) have immunomodulatory features. The aim of this study was to investigate the migration and homing potential of endogenous circulating MSC in virus negative inflammatory cardiomyopathy (CMi). Methods. In 29 patients with (n = 23) or without (n = 6) CMi undergoing endomyocardial biopsies (EMB), transcardiac gradients (TCGs) of circulating MSC were measured by flow cytometry from blood simultaneously sampled from aorta and coronary sinus. The presence of MSC in EMB, cardiac inflammation, and SDF-1α mRNA expression were detected via immunohistochemistry and real-time PCR. Results. MSC defined as CD45−CD34−CD11b−CD73+CD90+ cells accounted for 0.010 [0.0025–0.048]%/peripheral mononuclear cell (PMNC) and as CD45−CD34−CD11b−CD73+CD105+ cells for 0.019 [0.0026–0.067]%/PMNC, both with similar counts in patients with or without cardiac inflammation. There was a 29.9% (P < 0.01) transcardiac reduction of circulating MSC in patients with CMi, correlating with the extent of cardiac inflammation (P < 0.05, multivariate analysis). A strong correlation was found between the TCG of circulating MSC and numbers of MSC (CD45−CD34−CD90+CD105+) in EMB (r = −0.73, P < 0.005). SDF-1α was the strongest predictor for increased MSC in EMB (P < 0.005, multivariate analysis). Conclusions. Endogenous MSC continuously migrate to the heart in patients with CMi triggered by cardiac inflammation. PMID:25814787

  14. Fetal reprogramming and senescence in hypoplastic left heart syndrome and in human pluripotent stem cells during cardiac differentiation.

    PubMed

    Gaber, Naila; Gagliardi, Mark; Patel, Pranali; Kinnear, Caroline; Zhang, Cindy; Chitayat, David; Shannon, Patrick; Jaeggi, Edgar; Tabori, Uri; Keller, Gordon; Mital, Seema

    2013-09-01

    Hypoplastic left heart syndrome (HLHS) is a severe cardiac malformation characterized by left ventricle (LV) hypoplasia and abnormal LV perfusion and oxygenation. We studied hypoxia-associated injury in fetal HLHS and human pluripotent stem cells during cardiac differentiation to assess the effect of microenvironmental perturbations on fetal cardiac reprogramming. We studied LV myocardial samples from 32 HLHS and 17 structurally normal midgestation fetuses. Compared with controls, the LV in fetal HLHS samples had higher nuclear expression of hypoxia-inducible factor-1α but lower angiogenic growth factor expression, higher expression of oncogenes and transforming growth factor (TGF)-β1, more DNA damage and senescence with cell cycle arrest, fewer cardiac progenitors, myocytes and endothelial lineages, and increased myofibroblast population (P < 0.05 versus controls). Smooth muscle cells (SMCs) had less DNA damage compared with endothelial cells and myocytes. We recapitulated the fetal phenotype by subjecting human pluripotent stem cells to hypoxia during cardiac differentiation. DNA damage was prevented by treatment with a TGF-β1 inhibitor (P < 0.05 versus nonhypoxic cells). The hypoplastic LV in fetal HLHS samples demonstrates hypoxia-inducible factor-1α up-regulation, oncogene-associated cellular senescence, TGF-β1-associated fibrosis and impaired vasculogenesis. The phenotype is recapitulated by subjecting human pluripotent stem cells to hypoxia during cardiac differentiation and rescued by inhibition of TGF-β1. This finding suggests that hypoxia may reprogram the immature heart and affect differentiation and development.

  15. Beta2-adrenergic signaling affects the phenotype of human cardiac progenitor cells through EMT modulation.

    PubMed

    Pagano, Francesca; Angelini, Francesco; Siciliano, Camilla; Tasciotti, Julia; Mangino, Giorgio; De Falco, Elena; Carnevale, Roberto; Sciarretta, Sebastiano; Frati, Giacomo; Chimenti, Isotta

    2017-01-15

    Human cardiac progenitor cells (CPCs) offer great promises to cardiac cell therapy for heart failure. Many in vivo studies have shown their therapeutic benefits, paving the way for clinical translation. The 3D model of cardiospheres (CSs) represents a unique niche-like in vitro microenvironment, which includes CPCs and supporting cells. CSs have been shown to form through a process mediated by epithelial-to-mesenchymal transition (EMT). β2-Adrenergic signaling significantly affects stem/progenitor cells activation and mobilization in multiple tissues, and crosstalk between β2-adrenergic signaling and EMT processes has been reported. In the present study, we aimed at investigating the biological response of CSs to β2-adrenergic stimuli, focusing on EMT modulation in the 3D culture system of CSs. We treated human CSs and CS-derived cells (CDCs) with the β2-blocker butoxamine (BUT), using either untreated or β2 agonist (clenbuterol) treated CDCs as control. BUT-treated CS-forming cells displayed increased migration capacity and a significant increase in their CS-forming ability, consistently associated with increased expression of EMT-related genes, such as Snai1. Moreover, long-term BUT-treated CDCs contained a lower percentage of CD90+ cells, and this feature has been previously correlated with higher cardiogenic and therapeutic potential of the CDCs population. In addition, long-term BUT-treated CDCs had an increased ratio of collagen-III/collagen-I gene expression levels, and showed decreased release of inflammatory cytokines, overall supporting a less fibrosis-prone phenotype. In conclusion, β2 adrenergic receptor block positively affected the stemness vs commitment balance within CSs through the modulation of type1-EMT (so called "developmental"). These results further highlight type-1 EMT to be a key process affecting the features of resident cardiac progenitor cells, and mediating their response to the microenvironment.

  16. Cell Therapy in Ischemic Heart Disease: Interventions That Modulate Cardiac Regeneration

    PubMed Central

    Schaun, Maximiliano I.; Eibel, Bruna; Kristocheck, Melissa; Sausen, Grasiele; Machado, Luana; Koche, Andreia; Markoski, Melissa M.

    2016-01-01

    The incidence of severe ischemic heart disease caused by coronary obstruction has progressively increased. Alternative forms of treatment have been studied in an attempt to regenerate myocardial tissue, induce angiogenesis, and improve clinical conditions. In this context, cell therapy has emerged as a promising alternative using cells with regenerative potential, focusing on the release of paracrine and autocrine factors that contribute to cell survival, angiogenesis, and tissue remodeling. Evidence of the safety, feasibility, and potential effectiveness of cell therapy has emerged from several clinical trials using different lineages of adult stem cells. The clinical benefit, however, is not yet well established. In this review, we discuss the therapeutic potential of cell therapy in terms of regenerative and angiogenic capacity after myocardial ischemia. In addition, we addressed nonpharmacological interventions that may influence this therapeutic practice, such as diet and physical training. This review brings together current data on pharmacological and nonpharmacological approaches to improve cell homing and cardiac repair. PMID:26880938

  17. Purified eicosapentaenoic acid induces prolonged survival of cardiac allografts and generates regulatory T cells.

    PubMed

    Iwami, D; Zhang, Q; Aramaki, O; Nonomura, K; Shirasugi, N; Niimi, M

    2009-06-01

    Fish oil, which is rich in eicosapentaenoic acid (EPA), has been found to have immunomodulatory effects. We examined whether administration of purified EPA affected survival of fully mismatched murine cardiac allografts. Hearts from C57BL/10 (H-2(b)) mice were transplanted into CBA (H-2(k)) recipients treated with one intraperitoneal dose of purified EPA the day of transplantation. Untreated CBA recipients and recipients given 0.1 g/kg of EPA rejected C57BL/10 hearts (median survival time [MST], 8 and 13 days, respectively). With a 1.0 g/kg dose of EPA, graft survival was markedly prolonged (MST >100 days). To determine whether regulatory cells were generated, naïve mice (secondary recipients) underwent adoptive transfer of splenocytes from EPA-treated primary recipients and cardiac allograft transplantation. Adoptive transfer of whole, CD4(+) and CD4(+)CD25(+) splenocytes from EPA-treated recipients induced indefinite survival in secondary recipients. Flow cytometry showed that the CD4(+)CD25(+) cells were Foxp3(+). In reverse transcriptase-polymerase chain reaction (RT-PCR) studies, the expression of peroxisome proliferator-activated receptor gamma (PPARgamma) mRNA was upregulated by EPA treatment. A PPARgamma antagonist abrogated the prolongation of graft survival induced by EPA treatment (MST, 13 days). Thus, in our model, purified EPA induced prolonged survival of fully mismatched cardiac allografts and generated regulatory T cells dependent on PPARgamma activation.

  18. The TGFβ type II receptor plays a critical role in the endothelial cells during cardiac development.

    PubMed

    Robson, Andrew; Allinson, Kathleen R; Anderson, Robert H; Henderson, Deborah J; Arthur, Helen M

    2010-09-01

    TGFβ signalling is required for normal cardiac development. To investigate which cell types are involved, we used mice carrying a floxed Type II TGFβ receptor (Tgfbr2fl) allele and Cre-lox genetics to deplete this receptor in different regions of the heart. The three target tissues and corresponding Cre transgenic lines were atrioventricular myocardium (using cGata6-Cre), ventricular myocardium (using Mlc2v-Cre), and vascular endothelium (using tamoxifen-activated Cdh5(PAC)-CreERT2). Spatio-temporal Cre activity in each case was tracked via lacZ activation from the Rosa26R locus. Atrioventricular-myocardial-specific Tgfbr2 knockout (KO) embryos had short septal leaflets of the tricuspid valve, whereas ventricular myocardial-specific KO embryos mainly exhibited a normal cardiac phenotype. Inactivation of Tgfbr2 in endothelial cells from E11.5 resulted in deficient ventricular septation, accompanied by haemorrhage from cerebral blood vessels. We conclude that TGFβ signalling through the Tgfbr2 receptor, in endothelial cells, plays an important role in cardiac development, and is essential for cerebral vascular integrity.

  19. Enoxacin inhibits growth of prostate cancer cells and effectively restores microRNA processing

    PubMed Central

    Sousa, Elsa J.; Graça, Inês; Baptista, Tiago; Vieira, Filipa Q.; Palmeira, Carlos; Henrique, Rui; Jerónimo, Carmen

    2013-01-01

    Prostate cancer (PCa) is one of the most incident malignancies worldwide. Although efficient therapy is available for early-stage PCa, treatment of advanced disease is mainly ineffective and remains a clinical challenge. microRNA (miRNA) dysregulation is associated with PCa development and progression. In fact, several studies have reported a widespread downregulation of miRNAs in PCa, which highlights the importance of studying compounds capable of restoring the global miRNA expression. The main aim of this study was to define the usefulness of enoxacin as an anti-tumoral agent in PCa, due to its ability to induce miRNA biogenesis in a TRBP-mediated manner. Using a panel of five PCa cell lines, we observed that all of them were wild type for the TARBP2 gene and expressed TRBP protein. Furthermore, primary prostate carcinomas displayed normal levels of TRBP protein. Remarkably, enoxacin was able to decrease cell viability, induce apoptosis, cause cell cycle arrest, and inhibit the invasiveness of cell lines. Enoxacin was also effective in restoring the global expression of miRNAs. This study is the first to show that PCa cells are highly responsive to the anti-tumoral effects of enoxacin. Therefore, enoxacin constitutes a promising therapeutic agent for PCa. PMID:23644875

  20. p53 Restoration in Induction and Maintenance of Senescence: Differential Effects in Premalignant and Malignant Tumor Cells

    PubMed Central

    Harajly, Mohamad; Zalzali, Hasan; Nawaz, Zafar; Ghayad, Sandra E.; Ghamloush, Farah; Basma, Hussein; Zainedin, Samiha; Rabeh, Wissam; Jabbour, Mark; Tawil, Ayman; Badro, Danielle A.; Evan, Gerard I.

    2015-01-01

    The restoration of p53 has been suggested as a therapeutic approach in tumors. However, the timing of p53 restoration in relation to its efficacy during tumor progression still is unclear. We now show that the restoration of p53 in murine premalignant proliferating pineal lesions resulted in cellular senescence, while p53 restoration in invasive pineal tumors did not. The effectiveness of p53 restoration was not dependent on p19Arf expression but showed an inverse correlation with Mdm2 expression. In tumor cells, p53 restoration became effective when paired with either DNA-damaging therapy or with nutlin, an inhibitor of p53-Mdm2 interaction. Interestingly, the inactivation of p53 after senescence resulted in reentry into the cell cycle and rapid tumor progression. The evaluation of a panel of human supratentorial primitive neuroectodermal tumors (sPNET) showed low activity of the p53 pathway. Together, these data suggest that the restoration of the p53 pathway has different effects in premalignant versus invasive pineal tumors, and that p53 activation needs to be continually sustained, as reversion from senescence occurs rapidly with aggressive tumor growth when p53 is lost again. Finally, p53 restoration approaches may be worth exploring in sPNET, where the p53 gene is intact but the pathway is inactive in the majority of examined tumors. PMID:26598601

  1. Pluripotent stem cell derivation and differentiation toward cardiac muscle: novel techniques and advances in patent literature.

    PubMed

    Quattrocelli, Mattia; Thorrez, Lieven; Sampaolesi, Maurilio

    2013-04-01

    Pluripotent stem cells hold unprecedented potential for regenerative medicine, disease modeling and drug screening. Embryonic stem cells (ESCs), standard model for pluripotency studies, have been recently flanked by induced pluripotent stem cells (iPSCs). iPSCs are obtained from somatic cells via epigenetic and transcriptional reprogramming, overcoming ESC-related ethical issues and enabling the possibility of donor-matching pluripotent cell lines. Since the European Court of Justice banned patents involving embryo disaggregation to generate human ESCs, iPSCs can now fuel the willingness of European companies to invest in treatments based on stem cells. Moreover, iPSCs share many unique features of ESCs, such as unlimited self-renewal potential and broad differentiation capability, even though iPSCs seem more susceptible to genomic instability and display epigenetic biases as compared to ESCs. Both ESCs and iPSCs have been intensely investigated for cardiomyocyte production and cardiac muscle regeneration, both in human and animal models. In vitro and in vivo studies are continuously expanding and refining this field via genetic manipulation and cell conditioning, trying to achieve standard and reproducible products, eligible for clinical and biopharmaceutical scopes. This review focuses on the recently growing body of patents, concerning technical advances in production, expansion and cardiac differentiation of ESCs and iPSCs.

  2. Transforming growth factor-{beta}2 enhances differentiation of cardiac myocytes from embryonic stem cells

    SciTech Connect

    Kumar, Dinender . E-mail: Dinender.Kumar@uvm.edu; Sun, Baiming

    2005-06-24

    Stem cell therapy holds great promise for the treatment of injured myocardium, but is challenged by a limited supply of appropriate cells. Three different isoforms of transforming growth factor-{beta} (TGF-{beta}) -{beta}1, -{beta}2, and -{beta}3 exhibit distinct regulatory effects on cell growth, differentiation, and migration during embryonic development. We compared the effects of these three different isoforms on cardiomyocyte differentiation from embryonic stem (ES) cells. In contrast to TGF-{beta}1, or -{beta}3, treatment of mouse ES cells with TGF-{beta}2 isoform significantly increased embryoid body (EB) proliferation as well as the extent of the EB outgrowth that beat rhythmically. At 17 days, 49% of the EBs treated with TGF-{beta}2 exhibited spontaneous beating compared with 15% in controls. Cardiac myocyte specific protein markers sarcomeric myosin and {alpha}-actin were demonstrated in beating EBs and cells isolated from EBs. In conclusion, TGF-{beta}2 but not TGF-{beta}1, or -{beta}3 promotes cardiac myocyte differentiation from ES cells.

  3. Pluripotency of human embryonic and induced pluripotent stem cells for cardiac and vascular regeneration.

    PubMed

    Boheler, Kenneth R

    2010-07-01

    Cardiac and vascular abnormalities and disease syndromes are major causes of death both during human development and with aging. To identify the cause of congenital defects and to combat this epidemic in the aging population, new models must be created for scientific investigation and new therapies must be developed. Recent advances in pluripotent stem cell biology offer renewed hope for tackling these problems. Of particular importance has been the creation of induced pluripotent (iPS) cells from adult tissues and organs through the forced expression of two to four transcription factors. Moreover, iPS cells, which are phenotypically indistinguishable from embryonic stem (ES) cells, can be generated from any patient. This unique capacity when coupled with samples from patients who have congenital and genetic defects of unknown aetiology should permit the creation of new model systems that foment scientific investigation. Moreover, creation of patient-specific cells should overcome many of the immunological limitations that currently impede therapeutic applications associated with other pluripotent stem cells and their derivatives.The aims of this paper will be to discuss cardiac and vascular diseases and show how iPS cells may be employed to overcome some of the most significant scientific and clinical hurdles facing this field.

  4. Keratose Hydrogels Promote Vascular Smooth Muscle Differentiation from C-kit Positive Human Cardiac Stem Cells.

    PubMed

    Ledford, Benjamin T; Simmons, Jamelle; Chen, Miao; Fan, Huimin; Barron, Catherine; Liu, Zhongmin; Van Dyke, Mark; He, Jia-Qiang

    2017-03-28

    Stem cell-based therapies have demonstrated great potential for the treatment of cardiac diseases, e.g., myocardial infarction; however, low cell viability, low retention/engraftment, and uncontrollable in vivo differentiation after transplantation are still major limitations, which lead low therapeutic efficiency. Biomaterials provide a promising solution to overcome these issues due to their biocompatibility, biodegradability, low/non-immunogenicity, and low/non-cytotoxicity. The present study aims to investigate the impacts of Keratose (KOS) hydrogel biomaterial on cellular viability, proliferation, and differentiation of c-kit+ human cardiac stem cells (hCSCs). Briefly, hCSCs were cultured on both KOS hydrogel-coated dishes and regular tissue culture dishes (Blank control). Cell viability, stemness, proliferation, cellular morphology, and cardiac lineage differentiation were compared between KOS hydrogel and the Blank control at different time points. We found that KOS hydrogel is effective in maintaining hCSCs without any observable toxic effects, although cell size and proliferation rate appeared smaller on the KOS hydrogel compared to the Blank control. To our surprise, KOS hydrogel significantly promoted vascular smooth muscle cell (VSMC) differentiation (~72%), while on the Blank control dishes, most of the hCSCs (~78%) became cardiomyocytes. Further, we also observed "endothelial cell tube-like" microstructures formed by differentiated VSMCs only on KOS hydrogel, suggesting a potential capability of the hCSC-derived VSMCs for in vitro angiogenesis. To the best of our knowledge, this is the first report to discover the preferred differentiation of hCSCs toward VSMCs on KOS hydrogel. The underlying mechanism remains unknown. This innovative methodology may offer a new approach to generate a robust number of VSMCs simply by culturing hCSCs on KOS hydrogel, and the resulting VSMCs may be used in animal studies and clinical trials in

  5. Cardiac glycosides induce autophagy in human non-small cell lung cancer cells through regulation of dual signaling pathways.

    PubMed

    Wang, Yan; Qiu, Qiang; Shen, Jia-Jia; Li, Dian-Dong; Jiang, Xue-Jun; Si, Shu-Yi; Shao, Rong-Guang; Wang, Zhen

    2012-11-01

    Na(+)/K(+)-ATPase targeted cancer therapy has attracted increasing interests of oncologists in lung cancer field. Although multiple anti-cancer mechanisms of cardiac glycosides as Na(+)/K(+)-ATPase inhibitors are revealed, the role of autophagy and related molecular signaling pathway for the class of compounds in human non-small cell lung cancer (NSCLC) cells has not been systematically examined. We herein investigated the anti-cancer effects of two representative cardiac glycosides, digoxin and ouabain, in A549 and H460 cell lines. Both agents caused significant growth inhibition at nanomolar level. The cardiac glycosides were found to induce moderate G(2)/M arrest but not apoptosis at IC(50) level in the NSCLC cell lines. Moreover, autophagy was markedly induced by both agents, as evidenced by the time- and dose-dependent increase of LC3-II, up-regulation of Atg5 and Beclin1, as well as by the observations through acridine orange staining, transmission electron microscopy and quantification of GFP-LC3 fluorescence. Importantly, AMP-activated protein kinase (AMPK) pathway was activated, resulting in mammalian target of rapamycin (mTOR) deactivation during autophagy induction. Moreover, extracellular-signal-regulated kinase 1/2 (ERK1/2) activation was simultaneously found to be involved in the autophagy regulation. Co-treatment with respective inhibitors or siRNAs could either block the autophagic phenotypes and signals, or significantly increase the cellular viability, indicating the drugs-induced autophagy plays tumor-suppressing role. This work provides first evidence showing that the cardiac glycosides induce autophagy in human NSCLC cells through regulation of both mTOR and ERK1/2 signaling pathways. The autophagy may at least partially account for the growth inhibitory effects of the compounds in human NSCLC cells.

  6. A cardiac mitochondrial cAMP signaling pathway regulates calcium accumulation, permeability transition and cell death

    PubMed Central

    Wang, Z; Liu, D; Varin, A; Nicolas, V; Courilleau, D; Mateo, P; Caubere, C; Rouet, P; Gomez, A-M; Vandecasteele, G; Fischmeister, R; Brenner, C

    2016-01-01

    Although cardiac cytosolic cyclic 3′,5′-adenosine monophosphate (cAMP) regulates multiple processes, such as beating, contractility, metabolism and apoptosis, little is known yet on the role of this second messenger within cardiac mitochondria. Using cellular and subcellular approaches, we demonstrate here the local expression of several actors of cAMP signaling within cardiac mitochondria, namely a truncated form of soluble AC (sACt) and the exchange protein directly activated by cAMP 1 (Epac1), and show a protective role for sACt against cell death, apoptosis as well as necrosis in primary cardiomyocytes. Upon stimulation with bicarbonate (HCO3−) and Ca2+, sACt produces cAMP, which in turn stimulates oxygen consumption, increases the mitochondrial membrane potential (ΔΨm) and ATP production. cAMP is rate limiting for matrix Ca2+ entry via Epac1 and the mitochondrial calcium uniporter and, as a consequence, prevents mitochondrial permeability transition (MPT). The mitochondrial cAMP effects involve neither protein kinase A, Epac2 nor the mitochondrial Na+/Ca2+ exchanger. In addition, in mitochondria isolated from failing rat hearts, stimulation of the mitochondrial cAMP pathway by HCO3− rescued the sensitization of mitochondria to Ca2+-induced MPT. Thus, our study identifies a link between mitochondrial cAMP, mitochondrial metabolism and cell death in the heart, which is independent of cytosolic cAMP signaling. Our results might have implications for therapeutic prevention of cell death in cardiac pathologies. PMID:27100892

  7. Cardiac disease modeling using induced pluripotent stem cell-derived human cardiomyocytes.

    PubMed

    Dell'Era, Patrizia; Benzoni, Patrizia; Crescini, Elisabetta; Valle, Matteo; Xia, Er; Consiglio, Antonella; Memo, Maurizio

    2015-03-26

    Causative mutations and variants associated with cardiac diseases have been found in genes encoding cardiac ion channels, accessory proteins, cytoskeletal components, junctional proteins, and signaling molecules. In most cases the functional evaluation of the genetic alteration has been carried out by expressing the mutated proteins in in-vitro heterologous systems. While these studies have provided a wealth of functional details that have greatly enhanced the understanding of the pathological mechanisms, it has always been clear that heterologous expression of the mutant protein bears the intrinsic limitation of the lack of a proper intracellular environment and the lack of pathological remodeling. The results obtained from the application of the next generation sequencing technique to patients suffering from cardiac diseases have identified several loci, mostly in non-coding DNA regions, which still await functional analysis. The isolation and culture of human embryonic stem cells has initially provided a constant source of cells from which cardiomyocytes (CMs) can be obtained by differentiation. Furthermore, the possibility to reprogram cellular fate to a pluripotent state, has opened this process to the study of genetic diseases. Thus induced pluripotent stem cells (iPSCs) represent a completely new cellular model that overcomes the limitations of heterologous studies. Importantly, due to the possibility to keep spontaneously beating CMs in culture for several months, during which they show a certain degree of maturation/aging, this approach will also provide a system in which to address the effect of long-term expression of the mutated proteins or any other DNA mutation, in terms of electrophysiological remodeling. Moreover, since iPSC preserve the entire patients' genetic context, the system will help the physicians in identifying the most appropriate pharmacological intervention to correct the functional alteration. This article summarizes the current

  8. The effect of space microgravity on the physiological activity of mammalian resident cardiac stem cells

    NASA Astrophysics Data System (ADS)

    Belostotskaya, Galina; Zakharov, Eugeny

    Prolonged exposure to weightlessness during space flights is known to cause depression of heart function in mammals. The decrease in heart weight and its remodeling under the influence of prolonged weightlessness (or space microgravity) is assumed to be due to both morphological changes of working cardiomyocytes and their progressive loss, as well as to possible depletion of resident cardiac stem cells (CSCs) population, or their inability to self-renewal and regeneration of muscle tissue under conditions of weightlessness. We have previously shown that the presence of different maturity clones formed by resident CSCs not only in culture but also in the mammalian myocardium can be used as an indicator of the regenerative activity of myocardial cells [Belostotskaya, et al., 2013: 2014]. In this study, we were interested to investigate whether the 30-day near-Earth space flight on the spacecraft BION-M1 affects the regenerative potential of resident CSCs. Immediately after landing of the spacecraft, we had examined the presence of resident c-kit+, Sca-1+ and Isl1+ CSCs and their development in suspension of freshly isolated myocardial cells of C57BL mice in comparison to controls. Cardiac cell suspension was obtained by enzymatic digestion of the heart [Belostotskaya and Golovanova, 2014]. Immunocytochemically stained preparations of fixed cells were analyzed with confocal microscope Leica TCS SP5 (Germany) in the Resource Center of St-Petersburg State University. CSCs were labeled with appropriate antibodies. CSCs differentiation into mature cardiomyocytes was verified using antibodies to Sarcomeric α-Actinin and Cardiac Troponin T. Antibodies to Connexin43 were used to detect cell-cell contacts. All antibodies were conjugated with Alexa fluorochromes (488, 532, 546, 568, 594 and/or 647 nm), according to Zenon-technology (Invitrogen). It has been shown that, under identical conditions of cell isolation, more complete digestion of heart muscle was observed in

  9. "The state of the heart": Recent advances in engineering human cardiac tissue from pluripotent stem cells.

    PubMed

    Sirabella, Dario; Cimetta, Elisa; Vunjak-Novakovic, Gordana

    2015-08-01

    The pressing need for effective cell therapy for the heart has led to the investigation of suitable cell sources for tissue replacement. In recent years, human pluripotent stem cell research expanded tremendously, in particular since the derivation of human-induced pluripotent stem cells. In parallel, bioengineering technologies have led to novel approaches for in vitro cell culture. The combination of these two fields holds potential for in vitro generation of high-fidelity heart tissue, both for basic research and for therapeutic applications. However, this new multidisciplinary science is still at an early stage. Many questions need to be answered and improvements need to be made before clinical applications become a reality. Here we discuss the current status of human stem cell differentiation into cardiomyocytes and the combined use of bioengineering approaches for cardiac tissue formation and maturation in developmental studies, disease modeling, drug testing, and regenerative medicine.

  10. Inhomogeneity of action potential waveshape assists frequency entrainment of cardiac pacemaker cells.

    PubMed

    Cloherty, S L; Lovell, N H; Celler, B G; Dokos, S

    2001-10-01

    In this paper, we have employed ionic models of sinoatrial node cells to investigate the synchronization of a pair of coupled cardiac pacemaker cells from central and peripheral regions of the sinoatrial node. The free-running cycle length of the cell models was perturbed using two independent techniques and the minimum coupling conductance required to achieve frequency entrainment was used to assess the relative ease with which various cell pairs achieve entrainment. The factors effecting entrainment were further investigated using single-cell models paced with an artificial biphasic coupling current. Our simulation results suggest that dissimilar cell types, those with largely different upstroke velocities entrain more easily, that is, they require less coupling conductance to achieve 1:1 frequency entrainment. We, therefore, propose that regional variation in action-potential waveshape within the sinoatrial node assists frequency synchronization in vivo.

  11. Development of hairy cell leukemia in a patient after cardiac transplantation.

    PubMed

    Tsao, Lawrence; Chu, Kimberly E; Bhagat, Govind; Alobeid, Bachir

    2006-02-01

    Post-transplant lymphoproliferative disorders (PTLDs) are well-recognized complications of bone marrow and solid organ transplantation, comprising a heterogenous group of lymphoproliferations with a spectrum of morphologic, phenotypic and molecular features. Although PTLDs are usually Epstein-Barr virus-driven B-cell lymphoproliferations, T/natural killer-cell lymphoproliferations, multiple myeloma, and Hodgkin's lymphoma are also recognized as part of the PTLD spectrum. Hairy cell leukemia, a low-grade B-cell lymphoproliferation, has not been recognized as part of the PTLD spectrum. We report the first case of hairy cell leukemia occurring after cardiac transplantation. It is unclear whether this case, similar to other cases of low-grade B-cell lymphoproliferations reported after transplantation, is related to immunosuppression and therefore part of the spectrum of PTLDs, or merely represents coincidental event occurring in an immunocompromised patient.

  12. Effects of Trichothecenes on Cardiac Cell Electrical Function

    DTIC Science & Technology

    1985-12-16

    in horses, cattle, sheep, swine , and poultry (8). The primary causes of death were unknown, but the cardiovascular system always appeared to be...be used (such as gluconate ). Thus, KOH will be titrated to pH 7.4 with gluconic acid. For inside-out or cell-attached type patches, the bath will...contain 150 mM. K gluconate , 5 mM. HEPES, and the pipette will contain the same plus 1 mM. Ca++. With inside-out patches and the same K+ concentration on

  13. Fluid flow facilitates inward rectifier K+ current by convectively restoring [K+] at the cell membrane surface

    PubMed Central

    Kim, Jae Gon; Park, Sang Woong; Byun, Doyoung; Choi, Wahn Soo; Sung, Dong Jun; Shin, Kyung Chul; Kim, Hyun-ji; Leem, Young-Eun; Kang, Jong-Sun; Cho, Hana; Kim, Bokyung; Cho, Sung I; Bae, Young Min

    2016-01-01

    The inward rectifier Kir2.1 current (IKir2.1) was reported to be facilitated by fluid flow. However, the mechanism underlying this facilitation remains uncertain. We hypothesized that during K+ influx or efflux, [K+] adjacent to the outer mouth of the Kir2.1 channel might decrease or increase, respectively, compared with the average [K+] of the bulk extracellular solution, and that fluid flow could restore the original [K+] and result in the apparent facilitation of IKir2.1. We recorded the IKir2.1 in RBL-2H3 cells and HEK293T cells that were ectopically over-expressed with Kir2.1 channels by using the whole-cell patch-clamp technique. Fluid-flow application immediately increased the IKir2.1, which was not prevented by either the pretreatment with inhibitors of various protein kinases or the modulation of the cytoskeleton and caveolae. The magnitudes of the increases of IKir2.1 by fluid flow were driving force-dependent. Simulations performed using the Nernst-Planck mass equation indicated that [K+] near the membrane surface fell markedly below the average [K+] of the bulk extracellular solution during K+ influx, and, notably, that fluid flow restored the decreased [K+] at the cell surface in a flow rate-dependent manner. These results support the “convection-regulation hypothesis” and define a novel interpretation of fluid flow-induced modulation of ion channels. PMID:28004830

  14. Fluid flow facilitates inward rectifier K(+) current by convectively restoring [K(+)] at the cell membrane surface.

    PubMed

    Kim, Jae Gon; Park, Sang Woong; Byun, Doyoung; Choi, Wahn Soo; Sung, Dong Jun; Shin, Kyung Chul; Kim, Hyun-Ji; Leem, Young-Eun; Kang, Jong-Sun; Cho, Hana; Kim, Bokyung; Cho, Sung I; Bae, Young Min

    2016-12-22

    The inward rectifier Kir2.1 current (IKir2.1) was reported to be facilitated by fluid flow. However, the mechanism underlying this facilitation remains uncertain. We hypothesized that during K(+) influx or efflux, [K(+)] adjacent to the outer mouth of the Kir2.1 channel might decrease or increase, respectively, compared with the average [K(+)] of the bulk extracellular solution, and that fluid flow could restore the original [K(+)] and result in the apparent facilitation of IKir2.1. We recorded the IKir2.1 in RBL-2H3 cells and HEK293T cells that were ectopically over-expressed with Kir2.1 channels by using the whole-cell patch-clamp technique. Fluid-flow application immediately increased the IKir2.1, which was not prevented by either the pretreatment with inhibitors of various protein kinases or the modulation of the cytoskeleton and caveolae. The magnitudes of the increases of IKir2.1 by fluid flow were driving force-dependent. Simulations performed using the Nernst-Planck mass equation indicated that [K(+)] near the membrane surface fell markedly below the average [K(+)] of the bulk extracellular solution during K(+) influx, and, notably, that fluid flow restored the decreased [K(+)] at the cell surface in a flow rate-dependent manner. These results support the "convection-regulation hypothesis" and define a novel interpretation of fluid flow-induced modulation of ion channels.

  15. Partial Restoration of CFTR Function in cftr-Null Mice following Targeted Cell Replacement Therapy.

    PubMed

    Duchesneau, Pascal; Besla, Rickvinder; Derouet, Mathieu F; Guo, Li; Karoubi, Golnaz; Silberberg, Amanda; Wong, Amy P; Waddell, Thomas K

    2017-03-01

    Cystic fibrosis (CF) is a fatal recessive genetic disorder caused by a mutation in the gene encoding CF transmembrane conductance regulator (CFTR) protein. Alteration in CFTR leads to thick airway mucus and bacterial infection. Cell therapy has been proposed for CFTR restoration, but efficacy has been limited by low engraftment levels. In our previous studies, we have shown that using a pre-conditioning regimen in combination with optimization of cell number and time of delivery, we could obtain greater bone marrow cell (BMC) retention in the lung. Here, we found that optimized delivery of wild-type (WT) BMC contributed to apical CFTR expression in airway epithelium and restoration of select ceramide species and fatty acids in CFTR(-/-) mice. Importantly, WT BMC delivery delayed Pseudomonas aeruginosa lung infection and increased survival of CFTR(-/-) recipients. Only WT BMCs had a beneficial effect beyond 6 months, suggesting a dual mechanism of BMC benefit: a non-specific effect early after cell delivery, possibly due to the recruitment of macrophages and neutrophils, and a late beneficial effect dependent on long-term CFTR expression. Taken together, our results suggest that BMC can improve overall lung function and may have potential therapeutic benefit for the treatment of CF.

  16. Restoration of mutant bestrophin-1 expression, localisation and function in a polarised epithelial cell model

    PubMed Central

    Briant, Kit; Streit, Anne-Kathrin; Thomson, Steven; Koay, Yee Hui

    2016-01-01

    ABSTRACT Autosomal recessive bestrophinopathy (ARB) is a retinopathy caused by mutations in the bestrophin-1 protein, which is thought to function as a Ca2+-gated Cl− channel in the basolateral surface of the retinal pigment epithelium (RPE). Using a stably transfected polarised epithelial cell model, we show that four ARB mutant bestrophin-1 proteins were mislocalised and subjected to proteasomal degradation. In contrast to the wild-type bestrophin-1, each of the four mutant proteins also failed to conduct Cl− ions in transiently transfected cells as determined by whole-cell patch clamp. We demonstrate that a combination of two clinically approved drugs, bortezomib and 4-phenylbutyrate (4PBA), successfully restored the expression and localisation of all four ARB mutant bestrophin-1 proteins. Importantly, the Cl− conductance function of each of the mutant bestrophin-1 proteins was fully restored to that of wild-type bestrophin-1 by treatment of cells with 4PBA alone. The functional rescue achieved with 4PBA is significant because it suggests that this drug, which is already approved for long-term use in infants and adults, might represent a promising therapy for the treatment of ARB and other bestrophinopathies resulting from missense mutations in BEST1. PMID:27519691

  17. Human-induced pluripotent stem cell-derived cardiomyocytes for studies of cardiac ion transporters

    PubMed Central

    Fine, Michael; Lu, Fang-Min; Lin, Mei-Jung; Moe, Orson; Wang, Hao-Ran

    2013-01-01

    Human-induced pluripotent stem cells (hiPSCs) can differentiate into functional cardiomyocytes (iCell Cardiomyocytes) with ion channel activities that are remarkably similar to adult cardiomyocytes. Here, we extend this characterization to cardiac ion transporters. Additionally, we document facile molecular biological manipulation of iCell Cardiomyocytes to overexpress and knockdown transporters and regulatory proteins. Na/Ca exchange (NCX1) and Na/K pump currents were recorded via patch clamp, and Na/H and Cl/OH exchanges were recorded via oscillating proton-selective microelectrodes during patch clamp. Flux densities of all transport systems are similar to those of nonrodent adult cardiomyocytes. NCX1 protein and NCX1 currents decline after NCX1 small interfering (si)RNA transfection with similar time courses (τ ≈ 2 days), and an NCX1-Halo fusion protein is internalized after its extracellular labeling by AlexaFluor488 Ligand with a similar time course. Loss of the cardiac regulatory protein phospholemman (PLM) occurs over a longer time course (τ ≈ 60 h) after PLM small interfering RNA transfection. Similar to multiple previous reports for adult cardiomyocytes, Na/K pump currents in iCell Cardiomyocytes are not enhanced by activating cAMP production with either maximal or submaximal cytoplasmic Na and using either forskolin or isoproterenol to activate adenylate cyclases. Finally, we describe Ca influx-dependent changes of iCell Cardiomyocyte capacitance (Cm). Large increases of Cm occur during Ca influx via NCX1, thereby documenting large internal membrane reserves that can fuse to the sarcolemma, and subsequent declines of Cm document active endocytic processes. Together, these results document a great potential of iCell Cardiomyocytes for both short- and long-term studies of cardiac ion transporters and their regulation. PMID:23804202

  18. Murine cardiosphere-derived cells are impaired by age but not by cardiac dystrophic dysfunction.

    PubMed

    Hsiao, Lien-Cheng; Perbellini, Filippo; Gomes, Renata S M; Tan, Jun Jie; Vieira, Silvia; Faggian, Giuseppe; Clarke, Kieran; Carr, Carolyn A

    2014-05-01

    To be clinically relevant as a therapy for heart failure, endogenous progenitor cells must be isolated and expanded from aged and/or diseased tissue. Here, we investigated the effect of age and cardiac impairment resulting from lack of dystrophin on murine cardiosphere-derived cells (CDCs). CDCs were isolated and expanded from atrial biopsies from wild-type mice aged 1.5, 6, 18, and 24 months and from mdx mice aged 6 and 18 months. Cardiac function was measured in mdx mice and age-matched wild-type mice using high-resolution cine magnetic resonance imaging. CDCs could be isolated and expanded from all mice, however, the number of cells obtained, and their regenerative potential, decreased with age, as demonstrated by decreased expression of stem cell markers, c-kit and Sca-1, and decreased cell proliferation, migration, clonogenicity, and differentiation. Six-month-old mdx mice showed right ventricular (RV) dilation and reduced RV ejection fraction (EF) in comparison to wild-type mice. Older mdx mice displayed significant RV and left ventricular dilation and decreased EF in both ventricles, compared with age-matched wild-type mice. Mdx mouse hearts contained significantly more fibrotic tissue than age-matched wild-type mouse hearts. However, CDCs isolated from mice aged 6 and 18 months had the same number and regenerative potential from mdx mice and age-matched wild-type mice. Thus, the cardiac progenitor cell population is impaired by age but is not substantially altered by the progressive deterioration in function of the dystrophic heart.

  19. Influence of aging on the quantity and quality of human cardiac stem cells

    PubMed Central

    Nakamura, Tamami; Hosoyama, Tohru; Kawamura, Daichi; Takeuchi, Yuriko; Tanaka, Yuya; Samura, Makoto; Ueno, Koji; Nishimoto, Arata; Kurazumi, Hiroshi; Suzuki, Ryo; Ito, Hiroshi; Sakata, Kensuke; Mikamo, Akihito; Li, Tao-Sheng; Hamano, Kimikazu

    2016-01-01

    Advanced age affects various tissue-specific stem cells and decreases their regenerative ability. We therefore examined whether aging affected the quantity and quality of cardiac stem cells using cells obtained from 26 patients of various ages (from 2 to 83 years old). We collected fresh right atria and cultured cardiosphere-derived cells (CDCs), which are a type of cardiac stem cell. Then we investigated growth rate, senescence, DNA damage, and the growth factor production of CDCs. All samples yielded a sufficient number of CDCs for experiments and the cellular growth rate was not obviously associated with age. The expression of senescence-associated b-galactosidase and the DNA damage marker, gH2AX, showed a slightly higher trend in CDCs from older patients (≥65 years). The expression of VEGF, HGF, IGF-1, SDF-1, and TGF-b varied among samples, and the expression of these beneficial factors did not decrease with age. An in vitro angiogenesis assay also showed that the angiogenic potency of CDCs was not impaired, even in those from older patients. Our data suggest that the impact of age on the quantity and quality of CDCs is quite limited. These findings have important clinical implications for autologous stem cell transplantation in elderly patients. PMID:26947751

  20. Kupffer cell blockade prevents induction of portal venous tolerance in rat cardiac allograft transplantation

    SciTech Connect

    Kamei, T.; Callery, M.P.; Flye, M.W. )

    1990-05-01

    Pretransplant portal venous (pv) administration of donor antigen induces allospecific partial tolerance. Although the involved mechanism has not been defined, antigen presentation by Kupffer cells (KC) in the liver is considered to be critical. We evaluated the effect of KC blockade on this pv tolerance induction in Buffalo (RT1b) rats receiving Lewis (RT1(1)) cardiac heterotopic allografts. Control rats received no treatment, while experimental animals received 25 X 10(6) ultraviolet B-irradiated (12,000 J/m2) donor spleen cells via either the iv (systemic intravenous) or the pv routes 7 days before transplantation. Gadolinium chloride (GdCl3), a rare earth metal known to inhibit KC phagocytosis, was given (7 mg/kg) 1 and 2 days before pv preimmunization. Cardiac graft prolongation was obtained by pv (MST = 13.3 +/- 1.9 days, n = 6, vs control = 7.3 +/- 0.5 days, n = 6; P less than 0.001) but not by iv preimmunization (7.7 +/- 0.7 days, n = 6, NS vs control). KC blockade abolished the pv tolerance, as indicated by abrogation of graft prolongation (PV + GdCl3 = 8.0 +/- 0.8 days, n = 6, NS vs control). These findings suggest that effective alloantigen uptake by KC in the liver is essential for the induction of pv tolerance in rat cardiac transplantation.

  1. Combining erythropoietin infusion with intramyocardial delivery of bone marrow cells is more effective for cardiac repair.

    PubMed

    Zhang, Dingguo; Zhang, Fumin; Zhang, Yuqing; Gao, Xiang; Li, Chuanfu; Yang, Naiquan; Cao, Kejiang

    2007-02-01

    We postulated that combining erythropoietin (EPO) infusion with bone marrow mesenchymal stem cells (MSC) delivery may give better prognosis in a rat infarcted heart. Acute myocardial infarction (MI) model was developed by coronary artery ligation. Animals were grouped (n=18) to receive intramyocardial injection of 30 microl saline solution without cells (EPO and control groups) or with 3x10(6) MSC from transgenic green fluorescent protein (GFP)+ male mice (MSC and MSC-EPO groups). The animals received either 5000 U/kg body weight EPO (EPO and MSC-EPO groups) or saline solution (MSC and control groups) for 7 days after MI. Cardiac functions were measured by echocardiography and cardiac tissue was harvested for immunohistological studies 3 weeks after surgery. We observed regeneration of MSC in and around the infarcted myocardium in MSC and MSC-EPO groups. Capillary density was markedly enhanced with significantly smaller infarct size and reduced fibrotic area in MSC-EPO group as compared with other three groups. A smaller left ventricular (LV) diastolic dimension and a higher LV fractional shortening were observed in MSC-EPO group than in other three groups. Transplantation of MSC combined with cytokine EPO is superior to either of the monotherapy approach for angiomyogenesis and cardiac function recovery.

  2. SIRT Is Required for EDP-Mediated Protective Responses toward Hypoxia-Reoxygenation Injury in Cardiac Cells.

    PubMed

    Samokhvalov, Victor; Jamieson, Kristi L; Fedotov, Ilia; Endo, Tomoko; Seubert, John M

    2016-01-01

    Hypoxia-reoxygenation (H/R) injury is known to cause extensive injury to cardiac myocardium promoting development of cardiac dysfunction. Despite the vast number of studies dedicated to studying H/R injury, the molecular mechanisms behind it are multiple, complex, and remain very poorly understood, which makes development of novel pharmacological agents challenging. Docosahexaenoic acid (DHA, 22:6n3) is an n - 3 polyunsaturated fatty acid obtained from dietary sources, which produces numerous effects including regulation of cell survival and death mechanisms. The beneficial effects of DHA toward the cardiovascular system are well documented but the relative role of DHA or one of its more potent metabolites is unresolved. Emerging evidence indicates that cytochrome P450 (CYP) epoxygenase metabolites of DHA, epoxydocosapentaenoic acids (EDPs), have more potent biological activity than DHA in cardiac cells. In this study we examined whether EDPs protect HL-1 cardiac cells from H/R injury. Our observations demonstrate that treatment with 19,20-EDP protected HL-1 cardiac cells from H/R damage through a mechanism(s) protecting and enhancing mitochondrial quality. EDP treatment increased the relative rates of mitobiogenesis and mitochondrial respiration in control and H/R exposed cardiac cells. The observed EDP protective response toward H/R injury involved SIRT1-dependent pathways.

  3. Cardiac metastasis from renal cell carcinoma successfully treated with pazopanib: impact of TKIs' antiangiogenic activity.

    PubMed

    Schinzari, Giovanni; Monterisi, Santa; Signorelli, Diego; Cona, Silvia; Cassano, Alessandra; Danza, Francesco; Barone, Carlo

    2014-01-01

    Cardiac metastasis from renal cell carcinoma, especially without neoplastic thrombosis of the vena cava, is extremely rare. The prognosis of patients with metastatic renal cell carcinoma has been radically influenced by the introduction of tyrosine kinase inhibitors, but very few reports in the literature have described their activity in heart metastasis. We report the case of a woman with a left ventricle metastasis from kidney cancer without renal vein involvement, who was treated with pazopanib. The patient achieved a prolonged partial response, with clear signs of metastasis devascularization and a favorable toxicity profile.

  4. Different types of ganglion cell in the cardiac plexus of guinea-pigs.

    PubMed Central

    Edwards, F R; Hirst, G D; Klemm, M F; Steele, P A

    1995-01-01

    1. Intracellular recordings were made from the parasympathetic ganglion cells that lie in the epicardium of the left atrium of guinea-pig heart near the interatrial septum. 2. Three distinct types of neurone were identified on the basis of their electrophysiological properties. In one group of neurones, S cells, somatic action potentials were followed by brief after-hyperpolarizations. In the other two sets of neurones, somatic action potentials were followed by prolonged after-hyperpolarizations. The neurones with prominent after-hyperpolarization were further subdivided: one group of neurones, P cells, showed inward rectification at membrane potentials near the resting membrane potential whilst neurones in the other group, SAH cells, did so only at more negative potentials. 3. In the group of neurones that displayed inward rectification at potentials near rest, rectification resulted from the activation of an inward current, which resembled the hyperpolarization-activated inward current present in cardiac muscle pacemaker cells. 4. The three different types of neurone received different patterns of synaptic input. Each SAH cell received a synaptic excitatory connection from the vagus which in most cells released sufficient transmitter to initiate an action potential in that cell; several SAH cells also received a separate connection, which could be activated by local stimulation. Although most S cells failed to receive a synaptic input from the vagus, all of those tested received an excitatory synaptic input which could be activated by local stimulation. Virtually all P cells failed to receive a synaptic input from the vagus; in addition, local stimulation failed to initiate synaptic potentials in P cells. 5. When the structure of cardiac ganglion cells was determined, by loading the cells with either biocytin or neurobiotin, it was found that most cells lacked extensive dendritic processes. S cells were invariably monopolar, most P cells were dipolar or

  5. Effects of Matrix Metalloproteinases on the Performance of Platelet Fibrin Gel Spiked With Cardiac Stem Cells in Heart Repair

    PubMed Central

    Shen, Deliang; Tang, Junnan; Hensley, Michael Taylor; Li, Taosheng; Caranasos, Thomas George; Zhang, Tianxia

    2016-01-01

    Stem cells and biomaterials have been studied for therapeutic cardiac repair. Previous studies have shown the beneficial effects of platelet fibrin gel and cardiac stem cells when cotransplanted into rodent hearts with myocardial infarction (MI). We hypothesized that matrix metalloproteinases (MMPs) play an important role in such protection. Thus, the present study is designed to elucidate the effects of MMP inhibition on the therapeutic benefits of intramyocardial injection of platelet fibrin gel spiked with cardiac stem cells (cell-gel) in a rat model of acute MI. In vitro, broad-spectrum MMP inhibitor GM6001 undermines cell spreading and cardiomyocyte contraction. In a syngeneic rat model of myocardial infarction, MMP inhibition blunted the recruitment of endogenous cardiovascular cells into the injected biomaterials, therefore hindering de novo angiogenesis and cardiomyogenesis. Echocardiography and histology 3 weeks after treatment revealed that metalloproteinase inhibition diminished the functional and structural benefits of cell-gel in treating MI. Reduction of host angiogenesis, cardiomyocyte cycling, and MMP-2 activities was evident in animals treated with GM6001. Our findings suggest that MMPs play a critical role in the therapeutic benefits of platelet fibrin gel spiked with cardiac stem cells for treating MI. Significance In this study, the effects of matrix metalloproteinase inhibition on the performance of platelet gel spiked with cardiac stem cells (cell-gel) for heart regeneration are explored. The results demonstrate that matrix metalloproteinases are required for cell-gel to exert its benefits in cardiac repair. Inhibition of matrix metalloproteinases reduces cell engraftment, host angiogenesis, and recruitment of endogenous cardiovascular cells in rats with heart attack. PMID:27112177

  6. Exogenous arachidonate restores the dimethoate-induced inhibition of steroidogenesis in rat interstitial cells.

    PubMed

    Astiz, Mariana; Hurtado de Catalfo, Graciela; de Alaniz, María J T; Marra, Carlos Alberto

    2012-06-01

    The present work studies the potential restorative effect of polyunsaturated fatty acids (PUFA, 5 μM/24 h) on the dimethoate (DMT)-induced inhibition of testosterone biosynthesis in Leydig cells isolated from rat testes. Various fatty acids (FA) from the n-6 (18:2, 20:3, 20:4, 22:4 and 22:5) and n-3 (18.3, 20:5, 22:5, 22:6) series were assayed in Leydig cells, alone (as delipidated BSA complexes) and in combination with DMT (1 ppm). The n-6 FA stimulated lipid peroxidation (LPO) and inhibited the activities of steroidogenic enzymes (3β- and 17β-hydroxysteroid dehydrogenases). The n-3 FA exerted an anti-oxidant effect, decreasing the production of thiobarbituric-acid reactive substances (TBARS) and inhibiting phospholipase A(2) activity. The biosynthesis of testosterone in DMT-treated cultures was completely normalized by ARA (20:4n-6) and partially restored by the addition of 20:3n-6, increasing ARA content inside the mitochondria. The other FA assayed failed to restore androgenesis. COX-2 protein and prostaglandin F2α and E2 production were stimulated by 20:3n-6, ARA, 18:3n-3 and 20:5 n-3. COX-2 protein decreased upon addition of 22:5n-3 and 22:6n-3. StAR protein was increased by ARA and partially increased by 20:3n-6, likely due to its metabolic conversion into ARA. Both FA increased the mitochondrial cholesterol pool available for testosterone biosynthesis. The rate of androgenesis is likely the result of various regulatory factors acting concomitantly on the physiology of Leydig cells.

  7. A synthetic chloride channel restores chloride conductance in human cystic fibrosis epithelial cells.

    PubMed

    Shen, Bing; Li, Xiang; Wang, Fei; Yao, Xiaoqiang; Yang, Dan

    2012-01-01

    Mutations in the gene-encoding cystic fibrosis transmembrane conductance regulator (CFTR) cause defective transepithelial transport of chloride (Cl(-)) ions and fluid, thereby becoming responsible for the onset of cystic fibrosis (CF). One strategy to reduce the pathophysiology associated with CF is to increase Cl(-) transport through alternative pathways. In this paper, we demonstrate that a small synthetic molecule which forms Cl(-) channels to mediate Cl(-) transport across lipid bilayer membranes is capable of restoring Cl(-) permeability in human CF epithelial cells; as a result, it has the potential to become a lead compound for the treatment of human diseases associated with Cl(-) channel dysfunction.

  8. A Synthetic Chloride Channel Restores Chloride Conductance in Human Cystic Fibrosis Epithelial Cells

    PubMed Central

    Wang, Fei; Yao, Xiaoqiang; Yang, Dan

    2012-01-01

    Mutations in the gene-encoding cystic fibrosis transmembrane conductance regulator (CFTR) cause defective transepithelial transport of chloride (Cl−) ions and fluid, thereby becoming responsible for the onset of cystic fibrosis (CF). One strategy to reduce the pathophysiology associated with CF is to increase Cl− transport through alternative pathways. In this paper, we demonstrate that a small synthetic molecule which forms Cl− channels to mediate Cl− transport across lipid bilayer membranes is capable of restoring Cl− permeability in human CF epithelial cells; as a result, it has the potential to become a lead compound for the treatment of human diseases associated with Cl− channel dysfunction. PMID:22514656

  9. Restoration of Mitochondrial Gene Expression Using a Cloned Human Gene in Chinese Hamster Lung Cell Mutant

    PubMed Central

    Sherif, Zaki A; Broome, Carolyn W

    2015-01-01

    Background Gal−32 is a Chinese hamster lung cell nuclear mutant that is unable to grow in galactose due to a defect in mitochondrial protein synthesis. Since the product of the Gal−32 gene was unknown, it was imperative to use phenotypic complementation to clone a human gene that corrected the Gal−32 mutation. Results Recessive Gal−32 cells were co-transformed with pSV2-neo plasmid DNA and recombinant DNA from a human genomic library containing the dominant human Gal+ gene and a chloramphenicol-resistance (camr) gene present in the pSV13 vector. Primary transformants were selected by growth in galactose and the neomycin analog G418. In order to rescue the human Gal+ gene, a genomic library was constructed with primary transformant DNA and the pCV108 cosmid vector. The camr gene was used to identify clones with the nearby human sequences. DNA from two camr, Alu-hybridizing clones was able to transform the recessive Gal−32 cells to the Gal+ phenotype and to restore mitochondrial protein synthesis. Conclusion These data demonstrate the isolation of two pCV108-transformant recombinant clones containing a human gene that complements the Chinese hamster Gal−32 mutation and restores galactose metabolism. PMID:26052559

  10. The Role of Astrocytes in Mediating Exogenous Cell-Based Restorative Therapy for Stroke

    PubMed Central

    Li, Yi; Liu, Zhongwu; Xin, Hongqi; Chopp, Michael

    2014-01-01

    Astrocytes have not been a major therapeutic target for the treatment of stroke, with most research emphasis on the neuron. Given the essential role that astrocytes play in maintaining physiological function of the central nervous system and the very rapid and sensitive reaction astrocytes have in response to cerebral injury or ischemic insult, we propose to replace the neurocentric view for treatment with a more nuanced astrocytic centered approach. In addition, after decades of effort in attempting to develop neuroprotective therapies, which target reduction of the ischemic lesion, there are no effective clinical treatments for stroke, aside from thrombolysis with tissue plasminogen activator, which is used in a small minority of patients. A more promising therapeutic approach, which may affect nearly all stroke patients, may be in promoting endogenous restorative mechanisms, which enhance neurological recovery. A focus of efforts in stimulating recovery post stroke is the use of exogenously administered cells. The present review focuses on the role of the astrocyte in mediating the brain network, brain plasticity, and neurological recovery post stroke. As a model to describe the interaction of a restorative cell-based therapy with astrocytes, which drives recovery from stroke, we specifically highlight the subacute treatment of stroke with multipotent mesenchymal stromal cell therapy. PMID:24272702

  11. Cardiac actin is the major actin gene product in skeletal muscle cell differentiation in vitro.

    PubMed Central

    Bains, W; Ponte, P; Blau, H; Kedes, L

    1984-01-01

    We examined the expression of alpha-skeletal, alpha-cardiac, and beta- and gamma-cytoskeletal actin genes in a mouse skeletal muscle cell line (C2C12) during differentiation in vitro. Using isotype-specific cDNA probes, we showed that the alpha-skeletal actin mRNA pool reached only 15% of the level reached in adult skeletal muscle and required several days to attain this peak, which was then stably maintained. However, these cells accumulated a pool of alpha-cardiac actin six times higher than the alpha-skeletal actin mRNA peak within 24 h of the initiation of differentiation. After cells had been cultured for an additional 3 days, this pool declined to 10% of its peak level. In contrast, over 95% of the actin mRNA in adult skeletal muscle coded for alpha-actin. This suggests that C2C12 cells express a pattern of sarcomeric actin genes typical of either muscle development or regeneration and distinct from that seen in mature, adult tissue. Concurrently in the course of differentiation the beta- and gamma-cytoskeletal actin mRNA pools decreased to less than 10% of their levels in proliferating cells. The decreases in beta- and gamma-cytoskeletal actin mRNAs are apparently not coordinately regulated. Images PMID:6493226

  12. Cardiac conduction system

    MedlinePlus Videos and Cool Tools

    ... cardiac muscle cells in the walls of the heart that send signals to the heart muscle causing it to contract. The main components ... the cardiac conduction system's electrical activity in the heart.

  13. Restoring oxidant signaling suppresses pro-arthritogenic T-cell effector functions in rheumatoid arthritis

    PubMed Central

    Yang, Zhen; Shen, Yi; Oishi, Hisashi; Matteson, Eric L.; Tian, Lu; Goronzy, Jörg J.; Weyand, Cornelia M.

    2016-01-01

    To promote their pathology, CD4 T-cells from patients with rheumatoid arthritis (RA) have to clonally expand and differentiate into cytokine-producing effector cells. In contrast to healthy T-cells, naïve RA T-cells have a defect in glycolytic flux due to upregulation of glucose-6-phosphate dehydrogenase (G6PD). Excess G6PD shunts glucose into the pentose phosphate pathway (PPP), resulting in NADPH accumulation and ROS consumption. With surplus reductive equivalents, RA T-cells insufficiently activate the redox-sensitive kinase ATM; bypass the G2/M cell cycle checkpoint and hyperproliferate. Insufficient ATM activation biases T-cell differentiation towards the Th1 and Th17 lineages, imposing a hyper-inflammatory phenotype. We have identified several interventions that replenishing intracellular ROS, correct the abnormal proliferative behavior of RA T-cells and successfully suppress synovial inflammation. Rebalancing glucose utilization and restoring oxidant signaling may provide a novel therapeutic strategy to prevent autoimmunity in RA. PMID:27009267

  14. Liver restores immune homeostasis after local inflammation despite the presence of autoreactive T cells.

    PubMed

    Béland, Kathie; Lapierre, Pascal; Djilali-Saiah, Idriss; Alvarez, Fernando

    2012-01-01

    The liver must keep equilibrium between immune tolerance and immunity in order to protect itself from pathogens while maintaining tolerance to food antigens. An imbalance between these two states could result in an inflammatory liver disease. The aims of this study were to identify factors responsible for a break of tolerance and characterize the subsequent restoration of liver immune homeostasis. A pro-inflammatory environment was created in the liver by the co-administration of TLR ligands CpG and Poly(I:C) in presence or absence of activated liver-specific autoreactive CD8(+) T cells. Regardless of autoreactive CD8(+) T cells, mice injected with CpG and Poly(I:C) showed elevated serum ALT levels and a transient liver inflammation. Both CpG/Poly(I:C) and autoreactive CD8(+)T cells induced expression of TLR9 and INF-γ by the liver, and an up-regulation of homing and adhesion molecules CXCL9, CXCL10, CXCL16, ICAM-1 and VCAM-1. Transferred CFSE-labeled autoreactive CD8(+) T cells, in presence of TLR3 and 9 ligands, were recruited by the liver and spleen and proliferated. This population then contracted by apoptosis through intrinsic and extrinsic pathways. Up-regulation of FasL and PD-L1 in the liver was observed. In conclusion, TLR-mediated activation of the innate immune system results in a pro-inflammatory environment that promotes the recruitment of lymphocytes resulting in bystander hepatitis. Despite this pro-inflammatory environment, the presence of autoreactive CD8(+) T cells is not sufficient to sustain an autoimmune response against the liver and immune homeostasis is rapidly restored through the apoptosis of T cells.

  15. Reciprocal Modulation of IK1–INa Extends Excitability in Cardiac Ventricular Cells

    PubMed Central

    Varghese, Anthony

    2016-01-01

    The inwardly rectifying potassium current (IK1) and the fast inward sodium current (INa) are reciprocally modulated in mammalian ventricular myocytes. An increase in the expression of channels responsible for one of these two currents results in a corresponding increase in expression of the other. These currents are critical in the propagation of action potentials (AP) during the normal functioning of the heart. This study identifies a physiological role for IK1–INa reciprocal modulation in ventricular fiber activation thresholds and conduction. Simulations of action potentials in single cells and propagating APs in cardiac fibers were carried out using an existing model of electrical activity in cardiac ventricular myocytes. The conductances, GK1, of the inwardly rectifying potassium current, and GNa, of the fast inward sodium current were modified independently and in tandem to simulate reciprocal modulation. In single cells, independent modulation of GK1 alone resulted in changes in activation thresholds that were qualitatively similar to those for reciprocal GK1–GNa modulation and unlike those due to independent modulation of GNa alone, indicating that GK1 determines the cellular activation threshold. On the other hand, the variations in conduction velocity in cardiac cell fibers were similar for independent GNa modulation and for tandem changes in GK1–GNa, suggesting that GNa is primarily responsible for setting tissue AP conduction velocity. Conduction velocity dependence on GK1–GNa is significantly affected by the intercellular gap junction conductance. While the effects on the passive fiber space constant due to changes in both GK1 and the intercellular gap junction conductance, Ggj, were in line with linear cable theory predictions, both conductances had surprisingly large effects on fiber activation thresholds. Independent modulation of GK1 rendered cardiac fibers inexcitable at higher levels of GK1 whereas tandem GK1–GNa changes allowed fibers

  16. CD13 and ROR2 Permit Isolation of Highly Enriched Cardiac Mesoderm from Differentiating Human Embryonic Stem Cells

    PubMed Central

    Skelton, Rhys J.P.; Brady, Bevin; Khoja, Suhail; Sahoo, Debashis; Engel, James; Arasaratnam, Deevina; Saleh, Kholoud K.; Abilez, Oscar J.; Zhao, Peng; Stanley, Edouard G.; Elefanty, Andrew G.; Kwon, Murray; Elliott, David A.; Ardehali, Reza

    2016-01-01

    Summary The generation of tissue-specific cell types from human embryonic stem cells (hESCs) is critical for the development of future stem cell-based regenerative therapies. Here, we identify CD13 and ROR2 as cell-surface markers capable of selecting early cardiac mesoderm emerging during hESC differentiation. We demonstrate that the CD13+/ROR2+ population encompasses pre-cardiac mesoderm, which efficiently differentiates to all major cardiovascular lineages. We determined the engraftment potential of CD13+/ROR2+ in small (murine) and large (porcine) animal models, and demonstrated that CD13+/ROR2+ progenitors have the capacity to differentiate toward cardiomyocytes, fibroblasts, smooth muscle, and endothelial cells in vivo. Collectively, our data show that CD13 and ROR2 identify a cardiac lineage precursor pool that is capable of successful engraftment into the porcine heart. These markers represent valuable tools for further dissection of early human cardiac differentiation, and will enable a detailed assessment of human pluripotent stem cell-derived cardiac lineage cells for potential clinical applications. PMID:26771355

  17. CD13 and ROR2 Permit Isolation of Highly Enriched Cardiac Mesoderm from Differentiating Human Embryonic Stem Cells.

    PubMed

    Skelton, Rhys J P; Brady, Bevin; Khoja, Suhail; Sahoo, Debashis; Engel, James; Arasaratnam, Deevina; Saleh, Kholoud K; Abilez, Oscar J; Zhao, Peng; Stanley, Edouard G; Elefanty, Andrew G; Kwon, Murray; Elliott, David A; Ardehali, Reza

    2016-01-12

    The generation of tissue-specific cell types from human embryonic stem cells (hESCs) is critical for the development of future stem cell-based regenerative therapies. Here, we identify CD13 and ROR2 as cell-surface markers capable of selecting early cardiac mesoderm emerging during hESC differentiation. We demonstrate that the CD13+/ROR2+ population encompasses pre-cardiac mesoderm, which efficiently differentiates to all major cardiovascular lineages. We determined the engraftment potential of CD13+/ROR2+ in small (murine) and large (porcine) animal models, and demonstrated that CD13+/ROR2+ progenitors have the capacity to differentiate toward cardiomyocytes, fibroblasts, smooth muscle, and endothelial cells in vivo. Collectively, our data show that CD13 and ROR2 identify a cardiac lineage precursor pool that is capable of successful engraftment into the porcine heart. These markers represent valuable tools for further dissection of early human cardiac differentiation, and will enable a detailed assessment of human pluripotent stem cell-derived cardiac lineage cells for potential clinical applications.

  18. Cardiomyogenesis in the Developing Heart Is Regulated by c-kit-Positive Cardiac Stem Cells

    PubMed Central

    Ferreira-Martins, João; Ogórek, Barbara; Cappetta, Donato; Matsuda, Alex; Signore, Sergio; D'Amario, Domenico; Kostyla, James; Steadman, Elisabeth; Ide-Iwata, Noriko; Sanada, Fumihiro; Iaffaldano, Grazia; Ottolenghi, Sergio; Hosoda, Toru; Leri, Annarosa; Kajstura, Jan; Anversa, Piero; Rota, Marcello

    2012-01-01

    Rationale Embryonic and fetal myocardial growth is characterized by a dramatic increase in myocyte number, but whether the expansion of the myocyte compartment is dictated by activation and commitment of resident cardiac stem cells (CSCs), division of immature myocytes or both is currently unknown. Objectives In this study, we tested whether prenatal cardiac development is controlled by activation and differentiation of CSCs and whether division of c-kit-positive CSCs in the mouse heart is triggered by spontaneous Ca2+ oscillations. Results We report that embryonic-fetal c-kit-positive CSCs are self-renewing, clonogenic and multipotent in vitro and in vivo. The growth and commitment of c-kit-positive CSCs is responsible for the generation of the myocyte progeny of the developing heart. The close correspondence between values computed by mathematical modeling and direct measurements of myocyte number at E9, E14, E19 and one day after birth strongly suggests that the organogenesis of the embryonic heart is dependent on a hierarchical model of cell differentiation regulated by resident CSCs. The growth promoting effects of c-kit-positive CSCs are triggered by spontaneous oscillations in intracellular Ca2+, mediated by IP3 receptor activation, which condition asymmetric stem cell division and myocyte lineage specification. Conclusions Myocyte formation derived from CSC differentiation is the major determinant of cardiac growth during development. Division of c-kit-positive CSCs in the mouse is promoted by spontaneous Ca2+ spikes, which dictate the pattern of stem cell replication and the generation of a myocyte progeny at all phases of prenatal life and up to one day after birth. PMID:22275487

  19. Cardiac glycoside activities link Na(+)/K(+) ATPase ion-transport to breast cancer cell migration via correlative SAR.

    PubMed

    Magpusao, Anniefer N; Omolloh, George; Johnson, Joshua; Gascón, José; Peczuh, Mark W; Fenteany, Gabriel

    2015-02-20

    The cardiac glycosides ouabain and digitoxin, established Na(+)/K(+) ATPase inhibitors, were found to inhibit MDA-MB-231 breast cancer cell migration through an unbiased chemical genetics screen for cell motility. The Na(+)/K(+) ATPase acts both as an ion-transporter and as a receptor for cardiac glycosides. To delineate which function is related to breast cancer cell migration, structure-activity relationship (SAR) profiles of cardiac glycosides were established at the cellular (cell migration inhibition), molecular (Na(+)/K(+) ATPase inhibition), and atomic (computational docking) levels. The SAR of cardiac glycosides and their analogs revealed a similar profile, a decrease in potency when the parent cardiac glycoside structure was modified, for each activity investigated. Since assays were done at the cellular, molecular, and atomic levels, correlation of SAR profiles across these multiple assays established links between cellular activity and specific protein-small molecule interactions. The observed antimigratory effects in breast cancer cells are directly related to the inhibition of Na(+)/K(+) transport. Specifically, the orientation of cardiac glycosides at the putative cation permeation path formed by transmembrane helices αM1-M6 correlates with the Na(+) pump activity and cell migration. Other Na(+)/K(+) ATPase inhibitors that are structurally distinct from cardiac glycosides also exhibit antimigratory activity, corroborating the conclusion that the antiport function of Na(+)/K(+) ATPase and not the receptor function is important for supporting the motility of MDA-MB-231 breast cancer cells. Correlative SAR can establish new relationships between specific biochemical functions and higher-level cellular processes, particularly for proteins with multiple functions and small molecules with unknown or various modes of action.

  20. Fibronectin and Cyclic Strain Improve Cardiac Progenitor Cell Regenerative Potential In Vitro

    PubMed Central

    Ghosh-Choudhary, Shohini; Fierro, Marcos J.; Christman, Karen L.; Taylor, W. Robert

    2016-01-01

    Cardiac progenitor cells (CPCs) have rapidly advanced to clinical trials, yet little is known regarding their interaction with the microenvironment. Signaling cues present in the microenvironment change with development and disease. This work aims to assess the influence of two distinct signaling moieties on CPCs: cyclic biaxial strain and extracellular matrix. We evaluate four endpoints for improving CPC therapy: paracrine signaling, proliferation, connexin43 expression, and alignment. Vascular endothelial growth factor A (about 900 pg/mL) was secreted by CPCs cultured on fibronectin and collagen I. The application of mechanical strain increased vascular endothelial growth factor A secretion 2–4-fold for CPCs cultured on poly-L-lysine, laminin, or a naturally derived cardiac extracellular matrix. CPC proliferation was at least 25% higher on fibronectin than that on other matrices, especially for lower strain magnitudes. At 5% strain, connexin43 expression was highest on fibronectin. With increasing strain magnitude, connexin43 expression decreased by as much as 60% in CPCs cultured on collagen I and a naturally derived cardiac extracellular matrix. Cyclic mechanical strain induced the strongest CPC alignment when cultured on fibronectin or collagen I. This study demonstrates that culturing CPCs on fibronectin with 5% strain magnitude is optimal for their vascular endothelial growth factor A secretion, proliferation, connexin43 expression, and alignment. PMID:27610140

  1. 8-Oxoguanine DNA glycosylase 1 (ogg1) maintains the function of cardiac progenitor cells during heart formation in zebrafish

    SciTech Connect

    Yan, Lifeng; Zhou, Yong; Yu, Shanhe; Ji, Guixiang; Liu, Wei; Gu, Aihua

    2013-11-15

    Genomic damage may devastate the potential of progenitor cells and consequently impair early organogenesis. We found that ogg1, a key enzyme initiating the base-excision repair, was enriched in the embryonic heart in zebrafish. So far, little is known about DNA repair in cardiogenesis. Here, we addressed the critical role of ogg1 in cardiogenesis for the first time. ogg1 mainly expressed in the anterior lateral plate mesoderm (ALPM), the primary heart tube, and subsequently the embryonic myocardium by in situ hybridisation. Loss of ogg1 resulted in severe cardiac morphogenesis and functional abnormalities, including the short heart length, arrhythmia, decreased cardiomyocytes and nkx2.5{sup +} cardiac progenitor cells. Moreover, the increased apoptosis and repressed proliferation of progenitor cells caused by ogg1 deficiency might contribute to the heart phenotype. The microarray analysis showed that the expression of genes involved in embryonic heart tube morphogenesis and heart structure were significantly changed due to the lack of ogg1. Among those, foxh1 is an important partner of ogg1 in the cardiac development in response to DNA damage. Our work demonstrates the requirement of ogg1 in cardiac progenitors and heart development in zebrafish. These findings may be helpful for understanding the aetiology of congenital cardiac deficits. - Highlights: • A key DNA repair enzyme ogg1 is expressed in the embryonic heart in zebrafish. • We found that ogg1 is essential for normal cardiac morphogenesis in zebrafish. • The production of embryonic cardiomyocytes requires appropriate ogg1 expression. • Ogg1 critically regulated proliferation of cardiac progenitor cells in zebrafish. • foxh1 is a partner of ogg1 in the cardiac development in response to DNA damage.

  2. [Cardiac invasion of ATLL cells and therapeutic effects of local along with systemic treatments].

    PubMed

    Imoto, S; Nakagawa, T; Ito, M

    1989-07-01

    We report a rare case of adult T cell leukemia/lymphoma (ATLL) in which cardiac invasion was clinically demonstrated and treated effectively. A 45-year-old female was admitted because of exertional dyspnea and cervical tumors. The leukocyte count was 19,100/microliters with 20% of flower cells. HTLV-I antibody was positive. She was diagnosed as ATLL and treated with VEPA. She got remission for a short duration which was followed by relapse. OPEC was started as salvage therapy. In the course, extensive pericardial effusion was found in chest X-P. Pericardial puncture demonstrated ATLL cells and high titer of free IL-2 receptor (57,400U/ml) in the effusion. It was diagnosed as pericardial invasion of ATLL cells. Chemotherapy was started with new combination of drugs (cisplatin, mitoxantrone, ifosfamide, and prednisolone). Concomitantly pericardial drainage was performed and the drugs were administered directly into the pericardial cavity. The clinical improvement was obtained and pericardial effusion did not appear thereafter. She died 4 months after the diagnosis of cardiac invasion. On autopsy myocardial invasion was identified. The pericardium widely adhered and effusion measured 42 ml.

  3. Direct Mechanical Stimulation of Stem Cells: A Beating Electromechanically Active Scaffold for Cardiac Tissue Engineering.

    PubMed

    Gelmi, Amy; Cieslar-Pobuda, Artur; de Muinck, Ebo; Los, Marek; Rafat, Mehrdad; Jager, Edwin W H

    2016-06-01

    The combination of stem cell therapy with a supportive scaffold is a promising approach to improving cardiac tissue engineering. Stem cell therapy can be used to repair nonfunctioning heart tissue and achieve myocardial regeneration, and scaffold materials can be utilized in order to successfully deliver and support stem cells in vivo. Current research describes passive scaffold materials; here an electroactive scaffold that provides electrical, mechanical, and topographical cues to induced human pluripotent stem cells (iPS) is presented. The poly(lactic-co-glycolic acid) fiber scaffold coated with conductive polymer polypyrrole (PPy) is capable of delivering direct electrical and mechanical stimulation to the iPS. The electroactive scaffolds demonstrate no cytotoxic effects on the iPS as well as an increased expression of cardiac markers for both stimulated and unstimulated protocols. This study demonstrates the first application of PPy as a supportive electroactive material for iPS and the first development of a fiber scaffold capable of dynamic mechanical actuation.

  4. Fluorescence imaging of electrical activity in cardiac cells using an all-solid-state system.

    PubMed

    Entcheva, Emilia; Kostov, Yordan; Tchernev, Elko; Tung, Leslie

    2004-02-01

    Tracking spatial and temporal determinants of cardiac arrhythmogenesis at the cellular level presents challenges to the optical mapping techniques employed. In this paper, we describe a compact system combining two nontraditional low-cost solutions for excitation light sources and emission filters in fluorescence measurements of transmembrane potentials, Vm, or intracellular calcium, [Ca2+]i in cardiac cell networks. This is the first reported use of high-power blue and green light emitting diodes (LEDs), to excite cell monolayers stained with Vm - (di-8-ANEPPS) or [Ca2+]i - (Fluo-3) sensitive dyes. In addition, we use simple techniques for fabrication of suitable thin emission filters with uniform properties, no auto-fluorescence, high durability and good flexibility for imaging Vm or [Ca2+]i. The battery-operated LEDs and the fabricated emission filters, integrated with a fiber-optic system for contact fluorescence imaging, were used as tools to characterize conduction velocity restitution at the macro-scale. The versatility of the LEDs for illumination is further emphasized through 1) demonstration of their usage for epi-illumination recordings at the single-cell level, and 2) demonstration of their unique high-frequency light modulation ability. The LEDs showed excellent stability as excitation light sources for fluorescence measurements; acceptable signal-to-noise ratio and negligible cell photodamage and indicator dye photobleaching were observed.

  5. Translating stem cell research to cardiac disease therapies: pitfalls and prospects for improvement.

    PubMed

    Rosen, Michael R; Myerburg, Robert J; Francis, Darrel P; Cole, Graham D; Marbán, Eduardo

    2014-09-02

    Over the past 2 decades, there have been numerous stem cell studies focused on cardiac diseases, ranging from proof-of-concept to phase 2 trials. This series of papers focuses on the legacy of these studies and the outlook for future treatment of cardiac diseases with stem cell therapies. The first section by Drs. Rosen and Myerburg is an independent review that analyzes the basic science and translational strategies supporting the rapid advance of stem cell technology to the clinic, the philosophies behind them, trial designs, and means for going forward that may impact favorably on progress. The second and third sections were collected as responses to the initial section of this review. The commentary by Drs. Francis and Cole discusses the review by Drs. Rosen and Myerburg and details how trial outcomes can be affected by noise, poor trial design (particularly the absence of blinding), and normal human tendencies toward optimism and denial. The final, independent paper by Dr. Marbán takes a different perspective concerning the potential for positive impact of stem cell research applied to heart disease and future prospects for its clinical application. (Compiled by the JACC editors).

  6. Rate-dependent activation failure in isolated cardiac cells and tissue due to Na+ channel block

    PubMed Central

    Spindler, Anthony J.; Paterson, David; Noble, Denis

    2015-01-01

    While it is well established that class-I antiarrhythmics block cardiac sodium channels, the mechanism of action of therapeutic levels of these drugs is not well understood. Using a combination of mathematical modeling and in vitro experiments, we studied the failure of activation of action potentials in single ventricular cells and in tissue caused by Na+ channel block. Our computations of block and unblock of sodium channels by a theoretical class-Ib antiarrhythmic agent predict differences in the concentrations required to cause activation failure in single cells as opposed to multicellular preparations. We tested and confirmed these in silico predictions with in vitro experiments on isolated guinea-pig ventricular cells and papillary muscles stimulated at various rates (2–6.67 Hz) and exposed to various concentrations (5 × 10−6 to 500 × 10−6 mol/l) of lidocaine. The most salient result was that whereas large doses (5 × 10−4 mol/l or higher) of lidocaine were required to inhibit action potentials temporarily in single cells, much lower doses (5 × 10−6 mol/l), i.e., therapeutic levels, were sufficient to have the same effect in papillary muscles: a hundredfold difference. Our experimental results and mathematical analysis indicate that the syncytial nature of cardiac tissue explains the effects of clinically relevant doses of Na+ channel blockers. PMID:26342072

  7. Construction of three-dimensional vascularized cardiac tissue with cell sheet engineering.

    PubMed

    Sakaguchi, Katsuhisa; Shimizu, Tatsuya; Okano, Teruo

    2015-05-10

    Construction of three-dimensional (3D) tissues with pre-isolated cells is a promising achievement for novel medicine and drug-discovery research. Our laboratory constructs 3D tissues with an innovative and unique method for layering multiple cell sheets. Cell sheets maintain a high-efficiently regenerating function, because of the higher cell density and higher transplantation efficiency, compared to other cell-delivery methods. Cell sheets have already been applied in clinical applications for regenerative medicine in treating patients with various diseases. Therefore, in our search to develop a more efficient treatment with cell sheets, we are constructing 3D tissues by layering cell sheets. Native animal tissues and organs have an abundance of capillaries to supply oxygen and nutrients, and to remove waste molecules. In our investigation of vascularized cardiac cell sheets, we have found that endothelial cells within cell sheets spontaneously form blood vessel networks as in vivo capillaries. To construct even thicker 3D tissues by layering multiple cell sheets, it is critical to have a medium or blood flow within the vascular networks of the cell sheets. Therefore, to perfuse medium or blood in the cell sheet vascular network to maintain the viability of all cells, we developed two types of vascular beds; (1) a femoral muscle-based vascular bed, and (2) a synthetic collagen gel-based vascular bed. Both vascular beds successfully provide the critical flow of culture medium, which allows 12-layer cell sheets to survive. Such bioreactor systems, when combined with cell sheet engineering techniques, have produced functional vascularized 3D tissues. Here we explain and discuss the various processes to obtain vascular networks by properly connecting cell sheets and the engineering of 3D tissues.

  8. Restoration of E-cadherin sensitizes human melanoma cells for apoptosis.

    PubMed

    Kippenberger, Stefan; Loitsch, Stefan; Thaçi, Diamant; Müller, Jutta; Guschel, Maike; Kaufmann, Roland; Bernd, August

    2006-10-01

    Cell-cell adhesion is considered to be important in the development and maintenance of organ tissue. The spatial association between melanocytes and keratinocytes within human epidermis is achieved by homophilic interaction of E-cadherin molecules located on adjacent cells. In contrast, downregulation of E-cadherin expression in melanoma cells is considered as a key event in metastasis. Besides the adhesive properties, E-cadherin serves as a signal receptor linking to the cadherin-catenin signaling complex. As cadherins act as negative regulators of beta-catenin, a contribution to tumor formation seems likely. In the present study, it was tested whether ectopic expression of E-cadherin triggers apoptosis in human melanoma cell lines (G-361, JPC-298, SK-Mel-13). It was found that restoration of E-cadherin caused sensitization against drug-induced apoptosis. Particularly, the release of mitochondrial cytochrome c was increased in response to staurosporine. Moreover, activation of caspase-3 and caspase-8 was elevated. Similarly, DNA fragmentation, serving as a marker for advanced apoptosis, was amplified in cells transduced with E-cadherin. Interestingly, transduction with an E-cadherin construct lacking the extracellular domain showed no modified apoptosis. In conclusion, our findings suggest therapeutic strategies that enable expression of E-cadherin in order to sensitize human melanoma cells towards apoptosis.

  9. Speckle based configuration for simultaneous in vitro inspection of mechanical contractions of cardiac myocyte cells

    NASA Astrophysics Data System (ADS)

    Golberg, Mark; Fixler, Dror; Shainberg, Asher; Zlochiver, Sharon; Micó, Vicente; Garcia, Javier; Beiderman, Yevgeny; Zalevsky, Zeev

    2013-04-01

    In this manuscript we propose optical lensless configuration for a remote non-contact measuring of mechanical contractions of vast number of cardiac myocytes. All the myocytes were taken from rats, and the measurements were done in an in vitro mode. The optical method is based on temporal analysis of secondary reflected speckle patterns generated in lensless microscope configuration. The processing involves analyzing the movement and the change in the statistics of the generated secondary speckle patterns that are created on top of the cell culture when it is illuminated by a spot of laser beam. The main advantage of the proposed system is the ability to measure many cells simultaneously (approximately one thousand cells) and to extract the statistical data of their movement at once. The presented experimental results also include investigation the effect of isoproteranol on cells contraction process.

  10. Speckle-based configuration for simultaneous in vitro inspection of mechanical contractions of cardiac myocyte cells.

    PubMed

    Golberg, Mark; Fixler, Dror; Shainberg, Asher; Zlochiver, Sharon; Micó, Vicente; Garcia, Javier; Beiderman, Yevgeny; Zalevsky, Zeev

    2013-10-01

    An optical lensless configuration for a remote noncontact measuring of mechanical contractions of a vast number of cardiac myocytes is proposed. All the myocytes were taken from rats, and the measurements were done in an in vitro mode. The optical method is based on temporal analysis of secondary reflected speckle patterns generated in lensless microscope configuration. The processing involves analyzing the movement and the change in the statistics of the secondary speckle patterns that are created on top of the cell culture when it is illuminated by a spot of laser beam. The main advantage of the proposed system is the ability to measure many cells simultaneously (∼1000 cells) and to extract the statistical data of their movement at once. The presented experimental results also include investigation of the effect of isoproteranol on cell contraction process.

  11. Peptide-enhanced mRNA transfection in cultured mouse cardiac fibroblasts and direct reprogramming towards cardiomyocyte-like cells.

    PubMed

    Lee, Kunwoo; Yu, Pengzhi; Lingampalli, Nithya; Kim, Hyun Jin; Tang, Richard; Murthy, Niren

    2015-01-01

    The treatment of myocardial infarction is a major challenge in medicine due to the inability of heart tissue to regenerate. Direct reprogramming of endogenous cardiac fibroblasts into functional cardiomyocytes via the delivery of transcription factor mRNAs has the potential to regenerate cardiac tissue and to treat heart failure. Even though mRNA delivery to cardiac fibroblasts has the therapeutic potential, mRNA transfection in cardiac fibroblasts has been challenging. Herein, we develop an efficient mRNA transfection in cultured mouse cardiac fibroblasts via a polyarginine-fused heart-targeting peptide and lipofectamine complex, termed C-Lipo and demonstrate the partial direct reprogramming of cardiac fibroblasts towards cardiomyocyte cells. C-Lipo enabled the mRNA-induced direct cardiac reprogramming due to its efficient transfection with low toxicity, which allowed for multiple transfections of Gata4, Mef2c, and Tbx5 (GMT) mRNAs for a period of 2 weeks. The induced cardiomyocyte-like cells had α-MHC promoter-driven GFP expression and striated cardiac muscle structure from α-actinin immunohistochemistry. GMT mRNA transfection of cultured mouse cardiac fibroblasts via C-Lipo significantly increased expression of the cardiomyocyte marker genes, Actc1, Actn2, Gja1, Hand2, and Tnnt2, after 2 weeks of transfection. Moreover, this study provides the first direct evidence that the stoichiometry of the GMT reprogramming factors influence the expression of cardiomyocyte marker genes. Our results demonstrate that mRNA delivery is a potential approach for cardiomyocyte generation.

  12. Cell number per spheroid and electrical conductivity of nanowires influence the function of silicon nanowired human cardiac spheroids.

    PubMed

    Tan, Yu; Richards, Dylan; Coyle, Robert C; Yao, Jenny; Xu, Ruoyu; Gou, Wenyu; Wang, Hongjun; Menick, Donald R; Tian, Bozhi; Mei, Ying

    2017-03-15

    Human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) provide an unlimited cell source to treat cardiovascular diseases, the leading cause of death worldwide. However, current hiPSC-CMs retain an immature phenotype that leads to difficulties for integration with adult myocardium after transplantation. To address this, we recently utilized electrically conductive silicon nanowires (e-SiNWs) to facilitate self-assembly of hiPSC-CMs to form nanowired hiPSC cardiac spheroids. Our previous results showed addition of e-SiNWs effectively enhanced the functions of the cardiac spheroids and improved the cellular maturation of hiPSC-CMs. Here, we examined two important factors that can affect functions of the nanowired hiPSC cardiac spheroids: (1) cell number per spheroid (i.e., size of the spheroids), and (2) the electrical conductivity of the e-SiNWs. To examine the first factor, we prepared hiPSC cardiac spheroids with four different sizes by varying cell number per spheroid (∼0.5k, ∼1k, ∼3k, ∼7k cells/spheroid). Spheroids with ∼3k cells/spheroid was found to maximize the beneficial effects of the 3D spheroid microenvironment. This result was explained with a semi-quantitative theory that considers two competing factors: 1) the improved 3D cell-cell adhesion, and 2) the reduced oxygen supply to the center of spheroids with the increase of cell number. Also, the critical role of electrical conductivity of silicon nanowires has been confirmed in improving tissue function of hiPSC cardiac spheroids. These results lay down a solid foundation to develop suitable nanowired hiPSC cardiac spheroids as an innovative cell delivery system to treat cardiovascular diseases.

  13. Generation and characterization of human cardiac resident and non-resident mesenchymal stem cell.

    PubMed

    Subramani, Baskar; Subbannagounder, Sellamuthu; Palanivel, Sekar; Ramanathanpullai, Chithra; Sivalingam, Sivakumar; Yakub, Azhari; SadanandaRao, Manjunath; Seenichamy, Arivudainambi; Pandurangan, Ashok Kumar; Tan, Jun Jie; Ramasamy, Rajesh

    2016-10-01

    Despite the surgical and other insertional interventions, the complete recuperation of myocardial disorders is still elusive due to the insufficiency of functioning myocardiocytes. Thus, the use of stem cells to regenerate the affected region of heart becomes a prime important. In line with this human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) have gained considerable interest due to their potential use for mesodermal cell based replacement therapy and tissue engineering. Since MSCs are harvested from various organs and anatomical locations of same organism, thus the cardiac regenerative potential of human cardiac-derived MSCs (hC-MSCs) and human umbilical cord Wharton's Jelly derived MSC (hUC-MSCs) were tested concurrently. At in vitro culture, both hUC-MSCs and hC-MSCs assumed spindle shape morphology with expression of typical MSC markers namely CD105, CD73, CD90 and CD44. Although, hUC-MSCs and hC-MSCs are identical in term of morphology and immunophenotype, yet hUC-MSCs harbored a higher cell growth as compared to the hC-MSCs. The inherent cardiac regenerative potential of both cells were further investigated with mRNA expression of ion channels. The RT-PCR results demonstrated that both MSCs were expressing a notable level of delayed rectifier-like K(+) current (I KDR ) ion channel, yet the relative expression level was considerably varied between hUC-MSCs and hC-MSCs that Kv1.1(39 ± 0.6 vs 31 ± 0.8), Kv2.1 (6 ± 0.2 vs 21 ± 0.12), Kv1.5 (7.4 ± 0.1 vs 6.8 ± 0.06) and Kv7.3 (27 ± 0.8 vs 13.8 ± 0.6). Similarly, the Ca2(+)-activated K(+) current (I KCa ) channel encoding gene, transient outward K(+) current (I to ) and TTX-sensitive transient inward sodium current (I Na.TTX ) encoding gene (Kv4.2, Kv4.3 and hNE-Na) expressions were detected in both groups as well. Despite the morphological and phenotypical similarity, the present study also confirms the existence of multiple functional ion channel currents IKDR, IKCa, Ito

  14. Cardiac iron overload in chronically transfused patients with thalassemia, sickle cell anemia, or myelodysplastic syndrome.

    PubMed

    de Montalembert, Mariane; Ribeil, Jean-Antoine; Brousse, Valentine; Guerci-Bresler, Agnes; Stamatoullas, Aspasia; Vannier, Jean-Pierre; Dumesnil, Cécile; Lahary, Agnès; Touati, Mohamed; Bouabdallah, Krimo; Cavazzana, Marina; Chauzit, Emmanuelle; Baptiste, Amandine; Lefebvre, Thibaud; Puy, Hervé; Elie, Caroline; Karim, Zoubida; Ernst, Olivier; Rose, Christian

    2017-01-01

    The risk and clinical significance of cardiac iron overload due to chronic transfusion varies with the underlying disease. Cardiac iron overload shortens the life expectancy of patients with thalassemia, whereas its effect is unclear in those with myelodysplastic syndromes (MDS). In patients with sickle cell anemia (SCA), iron does not seem to deposit quickly in the heart. Our primary objective was to assess through a multicentric study the prevalence of cardiac iron overload, defined as a cardiovascular magnetic resonance T2*<20 ms, in patients with thalassemia, SCA, or MDS. Patient inclusion criteria were an accurate record of erythrocyte concentrates (ECs) received, a transfusion history >8 ECs in the past year, and age older than 6 years. We included from 9 centers 20 patients with thalassemia, 41 with SCA, and 25 with MDS in 2012-2014. Erythrocytapharesis did not consistently prevent iron overload in patients with SCA. Cardiac iron overload was found in 3 (15%) patients with thalassemia, none with SCA, and 4 (16%) with MDS. The liver iron content (LIC) ranged from 10.4 to 15.2 mg/g dry weight, with no significant differences across groups (P = 0.29). Abnormal T2* was not significantly associated with any of the measures of transfusion or chelation. Ferritin levels showed a strong association with LIC. Non-transferrin-bound iron was high in the thalassemia and MDS groups but low in the SCA group (P<0.001). Hepcidin was low in thalassemia, normal in SCA, and markedly elevated in MDS (P<0.001). Two mechanisms may explain that iron deposition largely spares the heart in SCA: the high level of erythropoiesis recycles the iron and the chronic inflammation retains iron within the macrophages. Thalassemia, in contrast, is characterized by inefficient erythropoiesis, unable to handle free iron. Iron accumulation varies widely in MDS syndromes due to the competing influences of abnormal erythropoiesis, excess iron supply, and inflammation.

  15. Cardiac iron overload in chronically transfused patients with thalassemia, sickle cell anemia, or myelodysplastic syndrome

    PubMed Central

    de Montalembert, Mariane; Ribeil, Jean-Antoine; Brousse, Valentine; Guerci-Bresler, Agnes; Stamatoullas, Aspasia; Vannier, Jean-Pierre; Dumesnil, Cécile; Lahary, Agnès; Touati, Mohamed; Bouabdallah, Krimo; Cavazzana, Marina; Chauzit, Emmanuelle; Baptiste, Amandine; Lefebvre, Thibaud; Puy, Hervé; Elie, Caroline

    2017-01-01

    The risk and clinical significance of cardiac iron overload due to chronic transfusion varies with the underlying disease. Cardiac iron overload shortens the life expectancy of patients with thalassemia, whereas its effect is unclear in those with myelodysplastic syndromes (MDS). In patients with sickle cell anemia (SCA), iron does not seem to deposit quickly in the heart. Our primary objective was to assess through a multicentric study the prevalence of cardiac iron overload, defined as a cardiovascular magnetic resonance T2*<20 ms, in patients with thalassemia, SCA, or MDS. Patient inclusion criteria were an accurate record of erythrocyte concentrates (ECs) received, a transfusion history >8 ECs in the past year, and age older than 6 years. We included from 9 centers 20 patients with thalassemia, 41 with SCA, and 25 with MDS in 2012-2014. Erythrocytapharesis did not consistently prevent iron overload in patients with SCA. Cardiac iron overload was found in 3 (15%) patients with thalassemia, none with SCA, and 4 (16%) with MDS. The liver iron content (LIC) ranged from 10.4 to 15.2 mg/g dry weight, with no significant differences across groups (P = 0.29). Abnormal T2* was not significantly associated with any of the measures of transfusion or chelation. Ferritin levels showed a strong association with LIC. Non-transferrin-bound iron was high in the thalassemia and MDS groups but low in the SCA group (P<0.001). Hepcidin was low in thalassemia, normal in SCA, and markedly elevated in MDS (P<0.001). Two mechanisms may explain that iron deposition largely spares the heart in SCA: the high level of erythropoiesis recycles the iron and the chronic inflammation retains iron within the macrophages. Thalassemia, in contrast, is characterized by inefficient erythropoiesis, unable to handle free iron. Iron accumulation varies widely in MDS syndromes due to the competing influences of abnormal erythropoiesis, excess iron supply, and inflammation. PMID:28257476

  16. Ligand dependent restoration of human TLR3 signaling and death in p53 mutant cells

    PubMed Central

    Menendez, Daniel; Lowe, Julie M.; Snipe, Joyce; Resnick, Michael A.

    2016-01-01

    Diversity within the p53 transcriptional network can arise from a matrix of changes that include target response element sequences and p53 expression level variations. We previously found that wild type p53 (WT p53) can regulate expression of most innate immune-related Toll-like-receptor genes (TLRs) in human cells, thereby affecting immune responses. Since many tumor-associated p53 mutants exhibit change-of-spectrum transactivation from various p53 targets, we examined the ability of twenty-five p53 mutants to activate endogenous expression of the TLR gene family in p53 null human cancer cell lines following transfection with p53 mutant expression vectors. While many mutants retained the ability to drive TLR expression at WT levels, others exhibited null, limited, or change-of-spectrum transactivation of TLR genes. Using TLR3 signaling as a model, we show that some cancer-associated p53 mutants amplify cytokine, chemokine and apoptotic responses after stimulation by the cognate ligand poly(I:C). Furthermore, restoration of WT p53 activity for loss-of-function p53 mutants by the p53 reactivating drug RITA restored p53 regulation of TLR3 gene expression and enhanced DNA damage-induced apoptosis via TLR3 signaling. Overall, our findings have many implications for understanding the impact of WT and mutant p53 in immunological responses and cancer therapy. PMID:27533082

  17. Antisense-induced exon skipping restores dystrophin expression in DMD patient derived muscle cells.

    PubMed

    van Deutekom, J C; Bremmer-Bout, M; Janson, A A; Ginjaar, I B; Baas, F; den Dunnen, J T; van Ommen, G J

    2001-07-15

    Due to frame-shifting mutations in the DMD gene that cause dystrophin deficiency, Duchenne muscular dystrophy (DMD) patients suffer from lethal muscle degeneration. In contrast, mutations in the allelic Becker muscular dystrophy (BMD) do not disrupt the translational reading frame, resulting in a less severe phenotype. In this study, we explored a genetic therapy aimed at restoring the reading frame in muscle cells from DMD patients through targeted modulation of dystrophin pre-mRNA splicing. Considering that exon 45 is the single most frequently deleted exon in DMD, whereas exon (45+46) deletions cause only a mild form of BMD, we set up an antisense-based system to induce exon 46 skipping from the transcript in cultured myotubes of both mouse and human origin. In myotube cultures from two unrelated DMD patients carrying an exon 45 deletion, the induced skipping of exon 46 in only approximately 15% of the mRNA led to normal amounts of properly localized dystrophin in at least 75% of myotubes. Our results provide first evidence of highly effective restoration of dystrophin expression from the endogenous gene in DMD patient-derived muscle cells. This strategy may be applicable to not only >65% of DMD mutations, but also many other genetic diseases.

  18. Cardiac troponin I is abnormally expressed in non-small cell lung cancer tissues and human cancer cells.

    PubMed

    Chen, Chao; Liu, Jia-Bao; Bian, Zhi-Ping; Xu, Jin-Dan; Wu, Heng-Fang; Gu, Chun-Rong; Shi, Yi; Zhang, Ji-Nan; Chen, Xiang-Jian; Yang, Di

    2014-01-01

    Cardiac troponin I (cTnI) is the only sarcomeric protein identified to date that is expressed exclusively in cardiac muscle. Its expression in cancer tissues has not been reported. Herein, we examined cTnI expression in non-small cell lung cancer (NSCLC) tissues, human adenocarcinoma cells SPCA-1 (lung) and BGC 823 (gastric) by immunohistochemistry, western blot analysis and real-time PCR. Immunopositivity for cTnI was demonstrated in 69.4% (34/49) NSCLC tissues evaluated, and was strong intensity in 35.3% (6/17) lung squamous cell carcinoma cases. The non-cancer-bearing lung tissues except tuberculosis (9/9, 100%) showed negative staining for cTnI. Seven monoclonal antibodies (mAbs) against human cTnI were applied in immunofluorescence. The result showed that the staining pattern within SPCA-1 and BGC 823 was dependent on the epitope of the cTnI mAbs. The membrane and nucleus of cancer cells were stained by mAbs against N-terminal peptides of cTnI, and cytoplasm was stained by mAbs against the middle and C-terminal peptides of cTnI. A ~25 kD band was identified by anti-cTnI mAb in SPCA-1 and BGC 823 extracts by western blot, as well as in cardiomyocyte extracts. The cTnI mRNA expressions in SPCA-1 and BGC 823 cells were about ten thousand times less than that in cardiomyocytes. Our study shows for the first time that cTnI protein and mRNA were abnormally expressed in NSCLC tissues, SPCA-1 and BGC 823 cells. These findings challenge the conventional view of cTnI as a cardiac-specific protein, enabling the potential use of cTnI as a diagnostic marker or targeted therapy for cancer.

  19. Activation of Dbl restores migration in polyamine-depleted intestinal epithelial cells via Rho-GTPases

    PubMed Central

    Bavaria, Mitulkumar N.; Bhattacharya, Sujoy; Johnson, Leonard R.

    2011-01-01

    Integrin binding to the extracellular matrix (ECM) activated Rho GTPases, Src, and focal adhesion kinase in intestinal epithelial cells (IEC)-6. Polyamine depletion inhibited activities of Rac1, RhoA, and Cdc42 and thereby migration. However, constitutively active (CA) Rac1 expression abolished the inhibitory effect of polyamine depletion, indicating that polyamines are involved in a process upstream of Rac1. In the present study, we examined the role of polyamines in the regulation of the guanine nucleotide exchange factor, diffuse B-cell lymphoma (Dbl), for Rho GTPases. Polyamine depletion decreased the level as well as the activation of Dbl protein. Dbl knockdown by siRNA altered cytoskeletal structure and decreased Rac1 activity and migration. Cells expressing CA-Dbl increased migration, Rac1 activity, and proliferation. CA-Dbl restored migration in polyamine-depleted cells by activating RhoA, Rac1, and Cdc42. CA-Dbl caused extensive reorganization of the F-actin cortex into stress fibers. Inhibition of Rac1 by NSC23766 significantly decreased migration of vector-transfected cells and CA-Dbl-transfected cells. However, the inhibition of migration was significantly higher in the vector-transfected cells compared with that seen in the CA-Dbl-transfected cells. Dbl localized in the perinuclear region in polyamine-depleted cells, whereas it localized with the stress fibers in control cells. CA-Dbl localized with stress fibers in both the control and polyamine-depleted cells. These results suggest that polyamines regulate the activation of Dbl, a membrane-proximal process upstream of Rac1. PMID:21372162

  20. Aptamer-Based Microfluidic Electrochemical Biosensor for Monitoring Cell-Secreted Trace Cardiac Biomarkers.

    PubMed

    Shin, Su Ryon; Zhang, Yu Shrike; Kim, Duck-Jin; Manbohi, Ahmad; Avci, Huseyin; Silvestri, Antonia; Aleman, Julio; Hu, Ning; Kilic, Tugba; Keung, Wendy; Righi, Martina; Assawes, Pribpandao; Alhadrami, Hani A; Li, Ronald A; Dokmeci, Mehmet R; Khademhosseini, Ali

    2016-10-04

    Continual monitoring of secreted biomarkers from organ-on-a-chip models is desired to understand their responses to drug exposure in a noninvasive manner. To achieve this goal, analytical methods capable of monitoring trace amounts of secreted biomarkers are of particular interest. However, a majority of existing biosensing techniques suffer from limited sensitivity, selectivity, stability, and require large working volumes, especially when cell culture medium is involved, which usually contains a plethora of nonspecific binding proteins and interfering compounds. Hence, novel analytical platforms are needed to provide noninvasive, accurate information on the status of organoids at low working volumes. Here, we report a novel microfluidic aptamer-based electrochemical biosensing platform for monitoring damage to cardiac organoids. The system is scalable, low-cost, and compatible with microfluidic platforms easing its integration with microfluidic bioreactors. To create the creatine kinase (CK)-MB biosensor, the microelectrode was functionalized with aptamers that are specific to CK-MB biomarker secreted from a damaged cardiac tissue. Compared to antibody-based sensors, the proposed aptamer-based system was highly sensitive, selective, and stable. The performance of the sensors was assessed using a heart-on-a-chip system constructed from human embryonic stem cell-derived cardiomyocytes following exposure to a cardiotoxic drug, doxorubicin. The aptamer-based biosensor was capable of measuring trace amounts of CK-MB secreted by the cardiac organoids upon drug treatments in a dose-dependent manner, which was in agreement with the beating behavior and cell viability analyses. We believe that, our microfluidic electrochemical biosensor using aptamer-based capture mechanism will find widespread applications in integration with organ-on-a-chip platforms for in situ detection of biomarkers at low abundance and high sensitivity.

  1. The cardiac stem cell compartment is indispensable for myocardial cell homeostasis, repair and regeneration in the adult.

    PubMed

    Nadal-Ginard, Bernardo; Ellison, Georgina M; Torella, Daniele

    2014-11-01

    Resident cardiac stem cells in embryonic, neonatal and adult mammalian heart have been identified by different membrane markers and transcription factors. However, despite a flurry of publications no consensus has been reached on the identity and actual regenerative effects of the adult cardiac stem cells. Intensive research on the adult mammalian heart's capacity for self-renewal of its muscle cell mass has led to a consensus that new cardiomyocytes (CMs) are indeed formed throughout adult mammalian life albeit at a disputed frequency. The physiological significance of this renewal, the origin of the new CMs, and the rate of adult CM turnover are still highly debated. Myocyte replacement, particularly after injury, was originally attributed to differentiation of a stem cell compartment. More recently, it has been reported that CMs are mainly replaced by the division of pre-existing post-mitotic CMs. These latter results, if confirmed, would shift the target of regenerative therapy toward boosting mature CM cell-cycle re-entry. Despite this controversy, it is documented that the adult endogenous c-kit(pos) cardiac stem cells (c-kit(pos) eCSCs) participate in adaptations to myocardial stress, and, when transplanted into the myocardium, regenerate most cardiomyocytes and microvasculature lost in an infarct. Nevertheless, the in situ myogenic potential of adult c-kit(pos) cardiac cells has been questioned. To revisit the regenerative potential of c-kit(pos) eCSCs, we have recently employed experimental protocols of severe diffuse myocardial damage in combination with several genetic murine models and cell transplantation approaches showing that eCSCs are necessary and sufficient for CM regeneration, leading to complete cellular, anatomical, and functional myocardial recovery. Here we will review the available data on adult eCSC biology and their regenerative potential placing it in the context of the different claimed mechanisms of CM replacement. These data are in

  2. Holographic analysis on deformation and restoration of malaria-infected red blood cells by antimalarial drug

    NASA Astrophysics Data System (ADS)

    Byeon, Hyeokjun; Ha, Young-Ran; Lee, Sang Joon

    2015-11-01

    Malaria parasites induce morphological, biochemical, and mechanical changes in red blood cells (RBCs). Mechanical variations are closely related to the deformability of individual RBCs. The deformation of various RBCs, including healthy and malaria-infected RBCs (iRBCs), can be directly observed through quantitative phase imaging (QPI). The effects of chloroquine treatment on the mechanical property variation of iRBCs were investigated using time-resolved holographic QPI of single live cells on a millisecond time scale. The deformabilities of healthy RBCs, iRBCs, and drug-treated iRBCs were compared, and the effect of chloroquine on iRBC restoration was experimentally examined. The present results are beneficial to elucidate the dynamic characteristics of iRBCs and the effect of the antimalarial drug on iRBCs.

  3. Impaired T-cell functions in aged guinea-pigs restored by thymostimulin (TS).

    PubMed

    Falchetti, R; Cafiero, C; Caprino, L

    1982-01-01

    The age-related changes of different T-cell activities in guinea pigs and the effect of Thymostimulin (TS), a thymus extract, on the immunocompetence of these cells was studied. Mitogen-induced proliferation of peripheral blood lymphocytes was increased by TS in vitro. The intraperitoneal administration of TS (5 mg/kg) to aged animals restored the helper function of T lymphocytes and enhanced the reactivity to mitogens of both peripheral blood lymphocytes and spleen lymphocytes. The data obtained suggest that as in other species, there is an age-associated decline of immunological response, in guinea pigs too, probably due to a deficiency of thymic hormone(s) and that TS could correct this deficiency.

  4. Glycemic control in diabetes is restored by therapeutic manipulation of cytokines that regulate beta cell stress.

    PubMed

    Hasnain, Sumaira Z; Borg, Danielle J; Harcourt, Brooke E; Tong, Hui; Sheng, Yonghua H; Ng, Choa Ping; Das, Indrajit; Wang, Ran; Chen, Alice C-H; Loudovaris, Thomas; Kay, Thomas W; Thomas, Helen E; Whitehead, Jonathan P; Forbes, Josephine M; Prins, Johannes B; McGuckin, Michael A

    2014-12-01

    In type 2 diabetes, hyperglycemia is present when an increased demand for insulin, typically due to insulin resistance, is not met as a result of progressive pancreatic beta cell dysfunction. This defect in beta cell activity is typically characterized by impaired insulin biosynthesis and secretion, usually accompanied by oxidative and endoplasmic reticulum (ER) stress. We demonstrate that multiple inflammatory cytokines elevated in diabetic pancreatic islets induce beta cell oxidative and ER stress, with interleukin-23 (IL-23), IL-24 and IL-33 being the most potent. Conversely, we show that islet-endogenous and exogenous IL-22, by regulating oxidative stress pathways, suppresses oxidative and ER stress caused by cytokines or glucolipotoxicity in mouse and human beta cells. In obese mice, antibody neutralization of IL-23 or IL-24 partially reduced beta cell ER stress and improved glucose tolerance, whereas IL-22 administration modulated oxidative stress regulatory genes in islets, suppressed ER stress and inflammation, promoted secretion of high-quality efficacious insulin and fully restored glucose homeostasis followed by restitution of insulin sensitivity. Thus, therapeutic manipulation of immune regulators of beta cell stress reverses the hyperglycemia central to diabetes pathology.

  5. Materializing Heart Regeneration: Biomimicry of Key Observations in Cell Transplantation Therapies and Natural Cardiac Regeneration

    NASA Astrophysics Data System (ADS)

    Kong, Yen P.; Jongpaiboonkit, Leena

    2016-07-01

    New regenerative paradigms are needed to address the growing global problem of heart failure as existing interventions are unsatisfactory. Outcomes from the current paradigm of cell transplantation have not been stellar but the mechanistic knowledge learned from them is instructive in the development of future paradigms. An emerging biomaterial-based approach incorporating key mechanisms and additional ones scrutinized from the process of natural heart regeneration in zebrafish may become the next evolution in cardiac repair. We highlight, with examples, tested key concepts and pivotal ones that may be integrated into a successful therapy.

  6. Adipose-Derived Mesenchymal Stem Cells Restore Impaired Mucosal Immune Responses in Aged Mice

    PubMed Central

    Aso, Kazuyoshi; Tsuruhara, Akitoshi; Takagaki, Kentaro; Oki, Katsuyuki; Ota, Megumi; Nose, Yasuhiro; Tanemura, Hideki; Urushihata, Naoki; Sasanuma, Jinichi; Sano, Masayuki; Hirano, Atsuyuki; Aso, Rio; McGhee, Jerry R.; Fujihashi, Kohtaro

    2016-01-01

    It has been shown that adipose-derived mesenchymal stem cells (AMSCs) can differentiate into adipocytes, chondrocytes and osteoblasts. Several clinical trials have shown the ability of AMSCs to regenerate these differentiated cell types. Age-associated dysregulation of the gastrointestinal (GI) immune system has been well documented. Our previous studies showed that impaired mucosal immunity in the GI tract occurs earlier during agingthan is seen in the systemic compartment. In this study, we examined the potential of AMSCs to restore the GI mucosal immune system in aged mice. Aged (>18 mo old) mice were adoptively transferred with AMSCs. Two weeks later, mice were orally immunized with ovalbumin (OVA) plus cholera toxin (CT) three times at weekly intervals. Seven days after the final immunization, when fecal extract samples and plasma were subjected to OVA- and CT-B-specific ELISA, elevated levels of mucosal secretory IgA (SIgA) and plasma IgG antibody (Ab) responses were noted in aged mouse recipients. Similar results were also seen aged mice which received AMSCs at one year of age. When cytokine production was examined, OVA-stimulated Peyer’s patch CD4+ T cells produced increased levels of IL-4. Further, CD4+ T cells from the lamina propria revealed elevated levels of IL-4 and IFN-γ production. In contrast, aged mice without AMSC transfer showed essentially no OVA- or CT-B-specific mucosal SIgA or plasma IgG Ab or cytokine responses. Of importance, fecal extracts from AMSC transferred aged mice showed neutralization activity to CT intoxication. These results suggest that AMSCs can restore impaired mucosal immunity in the GI tract of aged mice. PMID:26840058

  7. Multipotent human stromal cells improve cardiac function after myocardial infarction in mice without long-term engraftment

    SciTech Connect

    Iso, Yoshitaka; Spees, Jeffrey L.; E-mail: Jeffrey.Spees@uvm.edu; Serrano, Claudia; Bakondi, Benjamin; Pochampally, Radhika; Song, Yao-Hua; Sobel, Burton E.; Delafontaine, Patrick; Prockop, Darwin J. . E-mail: dprocko@tulane.edu

    2007-03-16

    The aim of this study was to determine whether intravenously administered multipotent stromal cells from human bone marrow (hMSCs) can improve cardiac function after myocardial infarction (MI) without long-term engraftment and therefore whether transitory paracrine effects or secreted factors are responsible for the benefit conferred. hMSCs were injected systemically into immunodeficient mice with acute MI. Cardiac function and fibrosis after MI in the hMSC-treated group were significantly improved compared with controls. However, despite the cardiac improvement, there was no evident hMSC engraftment in the heart 3 weeks after MI. Microarray assays and ELISAs demonstrated that multiple protective factors were expressed and secreted from the hMSCs in culture. Factors secreted by hMSCs prevented cell death of cultured cardiomyocytes and endothelial cells under conditions that mimicked tissue ischemia. The favorable effects of hMSCs appear to reflect the impact of secreted factors rather than engraftment, differentiation, or cell fusion.

  8. Transgenic systems for unequivocal identification of cardiac myocyte nuclei and analysis of cardiomyocyte cell cycle status.

    PubMed

    Raulf, Alexandra; Horder, Hannes; Tarnawski, Laura; Geisen, Caroline; Ottersbach, Annika; Röll, Wilhelm; Jovinge, Stefan; Fleischmann, Bernd K; Hesse, Michael

    2015-05-01

    Even though the mammalian heart has been investigated for many years, there are still uncertainties in the fields of cardiac cell biology and regeneration with regard to exact fractions of cardiomyocytes (CMs) at different developmental stages, their plasticity after cardiac lesion and also their basal turnover rate. A main shortcoming is the accurate identification of CM and the demonstration of CM division. Therefore, an in vivo model taking advantage of a live reporter-based identification of CM nuclei and their cell cycle status is needed. In this technical report, we describe the generation and characterization of embryonic stem cells and transgenic mice expressing a fusion protein of human histone 2B and the red fluorescence protein mCherry under control of the CM specific αMHC promoter. This fluorescence label allows unequivocal identification and quantitation of CM nuclei and nuclearity in isolated cells and native tissue slices. In ventricles of adults, we determined a fraction of <20 % CMs and binucleation of 77-90 %, while in atria a CM fraction of 30 % and a binucleation index of 14 % were found. We combined this transgenic system with the CAG-eGFP-anillin transgene, which identifies cell division and established a novel screening assay for cell cycle-modifying substances in isolated, postnatal CMs. Our transgenic live reporter-based system enables reliable identification of CM nuclei and determination of CM fractions and nuclearity in heart tissue. In combination with CAG-eGFP-anillin-mice, the cell cycle status of CMs can be monitored in detail enabling screening for proliferation-inducing substances in vitro and in vivo.

  9. Cardiac Repair With a Novel Population of Mesenchymal Stem Cells Resident in the Human Heart.

    PubMed

    Zhang, Yuan; Sivakumaran, Priyadharshini; Newcomb, Andrew E; Hernandez, Damián; Harris, Nicole; Khanabdali, Ramin; Liu, Guei-Sheung; Kelly, Darren J; Pébay, Alice; Hewitt, Alex W; Boyle, Andrew; Harvey, Richard; Morrison, Wayne A; Elliott, David A; Dusting, Gregory J; Lim, Shiang Y

    2015-10-01

    Cardiac resident stem cells (CRSCs) hold much promise to treat heart disease but this remains a controversial field. Here, we describe a novel population of CRSCs, which are positive for W8B2 antigen and were obtained from adult human atrial appendages. W8B2(+) CRSCs exhibit a spindle-shaped morphology, are clonogenic and capable of self-renewal. W8B2(+) CRSCs show high expression of mesenchymal but not hematopoietic nor endothelial markers. W8B2(+) CRSCs expressed GATA4, HAND2, and TBX5, but not C-KIT, SCA-1, NKX2.5, PDGFRα, ISL1, or WT1. W8B2(+) CRSCs can differentiate into cardiovascular lineages and secrete a range of cytokines implicated in angiogenesis, chemotaxis, inflammation, extracellular matrix remodeling, cell growth, and survival. In vitro, conditioned medium collected from W8B2(+) CRSCs displayed prosurvival, proangiogenic, and promigratory effects on endothelial cells, superior to that of other adult stem cells tested, and additionally promoted survival and proliferation of neonatal rat cardiomyocytes. Intramyocardial transplantation of human W8B2(+) CRSCs into immunocompromised rats 1 week after myocardial infarction markedly improved cardiac function (∼40% improvement in ejection fraction) and reduced fibrotic scar tissue 4 weeks after infarction. Hearts treated with W8B2(+) CRSCs showed less adverse remodeling of the left ventricle, a greater number of proliferating cardiomyocytes (Ki67(+) cTnT(+) cells) in the remote region, higher myocardial vascular density, and greater infiltration of CD163(+) cells (a marker for M2 macrophages) into the border zone and scar regions. In summary, W8B2(+) CRSCs are distinct from currently known CRSCs found in human hearts, and as such may be an ideal cell source to repair myocardial damage after infarction.

  10. Inhibitors of histone deacetylase (HDAC) restore the p53 pathway in neuroblastoma cells

    PubMed Central

    Condorelli, F; Gnemmi, I; Vallario, A; Genazzani, A A; Canonico, P L

    2007-01-01

    Background and purpose: Inhibitors of histone deacetylase (HDAC) are emerging as a promising class of anti-cancer drugs, but a generic deregulation of transcription in neoplastic cells cannot fully explain their therapeutic effects. In this study we evaluated alternative molecular mechanisms by which HDAC inhibitors could affect neuroblastoma viability. Experimental approach: Effects of HDAC inhibitors on survival of the I-type SK-N-BE and the N-type NB SH-SY5Y neuroblastoma cell lines were assessed by the MTT assay. Molecular pathways leading to this were examined by western blot, confocal microscopy and cytofluorometry. The mRNA levels of apoptotic mediators were assessed semi-quantitatively by RT-PCR. Tumour-suppressor p53 trans activity was assessed in EMSA experiments. HDAC inhibitors were also studied in cells subjected to plasmid-based p53 interference (p53i). Key results: HDAC inhibitors induced cell death via the mitochondrial pathway of apoptosis with recruitment of Bcl-2 family members. Bcl-2 overexpression rendered neuroblastoma cells resistant to HDAC inhibitor treatment. Low concentrations of HDAC inhibitors (0.9 mM) caused a G2 cell-cycle arrest and a marked upregulation of the p21/Waf1/Cip1 protein. HDAC inhibitors also activate the p53 protein via hyper-acetylation and nuclear re-localization, without affecting its protein expression. Accordingly, HDAC inhibitor-induced cell-killing and p21/Waf1/Cip1 upregulation is impaired in p53i-cells. Conclusions and implications: In neuroblastoma cells, HDAC inhibitors may overcome the resistance to classical chemotherapeutic drugs by restoring the p53 tumour-repressor function via its hyper-acetylation and nuclear migration, events usually impaired in such tumours. In neuroblastoma cells, HDAC inhibitors are not able to induce p21/Waf1/Cip1 in the absence of a functional p53. PMID:18059320

  11. Calcium is not required for triggering volume restoration in hypotonically challenged A549 epithelial cells.

    PubMed

    Ponomarchuk, Olga; Boudreault, Francis; Orlov, Sergei N; Grygorczyk, Ryszard

    2016-11-01

    Maintenance of cell volume is a fundamental housekeeping function in eukaryotic cells. Acute cell swelling activates a regulatory volume decrease (RVD) process with poorly defined volume sensing and intermediate signaling mechanisms. Here, we analyzed the putative role of Ca(2+) signaling in RVD in single substrate-adherent human lung epithelial A549 cells. Acute cell swelling was induced by perfusion of the flow-through imaging chamber with 50 % hypotonic solution at a defined fluid turnover rate. Changes in cytosolic Ca(2+) concentration ([Ca(2+)]i) and cell volume were monitored simultaneously with ratiometric Fura-2 fluorescence and 3D reconstruction of stereoscopic single-cell images, respectively. Hypotonic challenge caused a progressive swelling peaking at ∼20 min and followed, during the next 20 min, by RVD of 60 ± 7 % of the peak volume increase. However, at the rate of swelling used in our experiments, these processes were not accompanied by a measurable increment of [Ca(2+)]i. Loading with intracellular Ca(2+) chelator BAPTA slightly delayed peak of swelling but did not prevent RVD in 82 % of cells. Further, electrophysiology whole-cell patch-clamp experiments showed that BAPTA did not block activation of volume-regulated anion channel (VRAC) measured as swelling-induced outwardly rectifying 5-nitro-2-(3-phenylpropyl-amino) benzoic acid sensitive current. Together, our data suggest that intracellular Ca(2+)-mediated signaling is not essential for VRAC activation and subsequent volume restoration in A549 cells.

  12. Lamivudine treatment can restore T cell responsiveness in chronic hepatitis B.

    PubMed Central

    Boni, C; Bertoletti, A; Penna, A; Cavalli, A; Pilli, M; Urbani, S; Scognamiglio, P; Boehme, R; Panebianco, R; Fiaccadori, F; Ferrari, C

    1998-01-01

    High viral and/or antigen load may be an important cause of the T cell hyporesponsiveness to hepatitis B virus (HBV) antigens that is often observed in patients with chronic HBV infection. Reduction of viral and antigen load by lamivudine treatment represents an ideal model for investigating this hypothesis. HLA class II restricted T cell responses and serum levels of HBV-DNA, HBsAg, and HBeAg were studied before and during lamivudine treatment in 12 patients with hepatitis B e antigen positive chronic active hepatitis B to assess possible correlations between viral and/or antigen load and vigor of the T cell response. Cell proliferation to HBV nucleocapsid antigens and peptides and frequency of circulating HBV nucleocapsid-specific T cells were assessed to characterize CD4-mediated responses. A highly significant enhancement of the CD4-mediated response to HBV nucleocapsid antigens was already detectable in most patients 7-14 d after the start of lamivudine treatment. This effect was dramatic and persistent in 10 patients but undetectable in 2. It occurred concomitant with a rapid and marked reduction of viremia. Interestingly, lamivudine also enhanced the responses to mitogens and recall antigens, showing that its effect was not limited to HBV-specific T cells. In conclusion, an efficient antiviral T cell response can be restored by lamivudine treatment in patients with chronic hepatitis B concurrently with reduction of viremia, indicating the importance of viral load in the pathogenesis of T cell hyporesponsiveness in these patients. Since lamivudine treatment can overcome T cell hyporeactivity, combining lamivudine with treatments directed to stimulate the T cell response may represent an effective strategy to induce eradication of chronic HBV infection. PMID:9727065

  13. Biorealistic cardiac cell culture platforms with integrated monitoring of extracellular action potentials

    PubMed Central

    Trantidou, Tatiana; Terracciano, Cesare M.; Kontziampasis, Dimitrios; Humphrey, Eleanor J.; Prodromakis, Themistoklis

    2015-01-01

    Current platforms for in vitro drug development utilize confluent, unorganized monolayers of heart cells to study the effect on action potential propagation. However, standard cell cultures are of limited use in cardiac research, as they do not preserve important structural and functional properties of the myocardium. Here we present a method to integrate a scaffolding technology with multi-electrode arrays and deliver a compact, off-the-shelf monitoring platform for growing biomimetic cardiac tissue. Our approach produces anisotropic cultures with conduction velocity (CV) profiles that closer resemble native heart tissue; the fastest impulse propagation is along the long axis of the aligned cardiomyocytes (CVL) and the slowest propagation is perpendicular (CVT), in contrast to standard cultures where action potential propagates isotropically (CVL ≈ CVT). The corresponding anisotropy velocity ratios (CVL/CVT = 1.38 – 2.22) are comparable with values for healthy adult rat ventricles (1.98 – 3.63). The main advantages of this approach are that (i) it provides ultimate pattern control, (ii) it is compatible with automated manufacturing steps and (iii) it is utilized through standard cell culturing protocols. Our platform is compatible with existing read-out equipment and comprises a prompt method for more reliable CV studies. PMID:26053434

  14. Endothelial cell dysfunction and cardiac hypertrophy in the STOX1 model of preeclampsia

    PubMed Central

    Ducat, Aurélien; Doridot, Ludivine; Calicchio, Rosamaria; Méhats, Celine; Vilotte, Jean-Luc; Castille, Johann; Barbaux, Sandrine; Couderc, Betty; Jacques, Sébastien; Letourneur, Franck; Buffat, Christophe; Le Grand, Fabien; Laissue, Paul; Miralles, Francisco; Vaiman, Daniel

    2016-01-01

    Preeclampsia is a disease of pregnancy involving systemic endothelial dysfunction. However, cardiovascular consequences of preeclampsia are difficult to analyze in humans. The objective of the present study is to evaluate the cardiovascular dysfunction induced by preeclampsia by examining the endothelium of mice suffering of severe preeclampsia induced by STOX1 overexpression. Using Next Generation Sequencing on endothelial cells of mice carrying either transgenic or control embryos, we discovered significant alterations of gene networks involved in inflammation, cell cycle, and cardiac hypertrophy. In addition, the heart of the preeclamptic mice revealed cardiac hypertrophy associated with histological anomalies. Bioinformatics comparison of the networks of modified genes in the endothelial cells of the preeclamptic mice and HUVECs exposed to plasma from preeclamptic women identified striking similarities. The cardiovascular alterations in the pregnant mice are comparable to those endured by the cardiovascular system of preeclamptic women. The STOX1 mice could help to better understand the endothelial dysfunction in the context of preeclampsia, and guide the search for efficient therapies able to protect the maternal endothelium during the disease and its aftermath. PMID:26758611

  15. Connexin43 remodeling caused by inhibition of plakophilin-2 expression in cardiac cells.

    PubMed

    Oxford, Eva M; Musa, Hassan; Maass, Karen; Coombs, Wanda; Taffet, Steven M; Delmar, Mario

    2007-09-28

    Desmosomes and gap junctions are distinct structural components of the cardiac intercalated disc. Here, we asked whether the presence of plakophilin (PKP)2, a component of the desmosome, is essential for the proper function and distribution of the gap junction protein connexin (Cx)43. We used RNA silencing technology to decrease the expression of PKP2 in cardiac cells (ventricular myocytes, as well as epicardium-derived cells) obtained from neonatal rat hearts. We evaluated the content, distribution, and function of Cx43 gap junctions. Our results show that loss of PKP2 expression led to a decrease in total Cx43 content, a significant redistribution of Cx43 to the intracellular space, and a decrease in dye coupling between cells. Separate experiments showed that Cx43 and PKP2 can coexist in the same macromolecular complex. Our results support the notion of a molecular crosstalk between desmosomal and gap junction proteins. The results are discussed in the context of arrhythmogenic right ventricular cardiomyopathy, an inherited disease involving mutations in desmosomal proteins, including PKP2.

  16. STREAMLINED APPROACH FOR ENVIRONMENTAL RESTORATION PLAN FOR CORRECTIVE ACTION UNIT 116: AREA 25 TEST CELL C FACILITYNEVADA TEST SITE, NEVADA

    SciTech Connect

    2006-07-01

    This Streamlined Approach for Environmental Restoration Plan identifies the activities required for the closure of Corrective Action Unit 116, Area 25 Test Cell C Facility. The Test Cell C Facility is located in Area 25 of the Nevada Test Site approximately 25 miles northwest of Mercury, Nevada.

  17. Reversible interruption of gap junctional communication by testosterone propionate in cultured Sertoli cells and cardiac myocytes.

    PubMed

    Pluciennik, F; Verrecchia, F; Bastide, B; Hervé, J C; Joffre, M; Délèze, J

    1996-02-01

    A direct cell-to-cell exchange of ions and molecules occurs through specialized membrane channels built by the interaction of two half channels, termed connexons, contributed by each of the two adjacent cells. The electrical and diffusional couplings have been investigated by monitoring respectively the cell-to-cell conductance and the fluorescence recovery after photobleaching, in Sertoli and cardiac cells of young rat. In both cell types, a rapid impairment of the intercellular coupling has been observed in the presence of testosterone propionate. This interruption of the cell-to-cell communication through gap junction channels was dose-dependent, observed in the concentration range 1 to 25 microM and was progressively reversed after withdrawing the testosterone ester. Pretreatment with cyproterone acetate, an antiandrogen which blocks the nuclear testosterone receptor by binding, did not prevent the uncoupling action of the androgen ester. This observation, together with the rapid time course of the uncoupling and recoupling, and the rather high effective concentration (micromolar) of the steroid compound, suggests a nongenomic mechanism of action. The uncoupling concentrations were very similar to those of other steroid compounds known to interrupt gap junctional communication. The uncoupling could result from a direct interaction of the steroid with the proteolipidic structure of the membrane, that might alter the conformation of the gap junction channels and their functional state.

  18. In situ crosslinkable elastomeric hydrogel for long-term cell encapsulation for cardiac applications.

    PubMed

    Komeri, Remya; Muthu, Jayabalan

    2016-12-01

    The regenerative therapy of tissues relays on successful cell transplantation and engraftment. Soft hydrogel carriers are employed to protect transplanted cells from harmful microenvironment in soft tissue regeneration. Herein an injectable, porous, biodegradable, bioresorbable, and elastomeric hydrogel fabricated from poly(propylene fumarate-co-sebacate-co-ethylene glycol) crosslinked with PEGDA for cardiomyoblast encapsulation was reported. The hydrogel retains adequate mechanical property in the range of native myocardium even after 30 days of degradation (49 ± 0.008 kPa). The hydrogel shows maximum extensibility without collapsing even under 60% compression. The hydrogel retains 70.58% equilibrium water content, wide internal porosity, and slow bulk degradation favorable for cell carriers. The cardiomyoblast cells encapsulated in hydrogel retains viability even after 30 days of culture. The long-term viability and proliferation studies of encapsulated cells in the hydrogel substantiate the suitability of hydrogel microenvironment for cell survival. The present hydrogel is a potential cell carrier with favorable physical and biological properties for cell encapsulation for cardiac applications. The candidate hydrogels perform better than the other reported elastomeric hydrogels fabricated for cell therapy. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 2936-2944, 2016.

  19. LXR agonist treatment of blastic plasmacytoid dendritic cell neoplasm restores cholesterol efflux and triggers apoptosis

    PubMed Central

    Ceroi, Adam; Masson, David; Roggy, Anne; Roumier, Christophe; Chagué, Cécile; Gauthier, Thierry; Philippe, Laure; Lamarthée, Baptiste; Angelot-Delettre, Fanny; Bonnefoy, Francis; Perruche, Sylvain; Biichle, Sabeha; Preudhomme, Claude; Macintyre, Elisabeth; Lagrost, Laurent; Garnache-Ottou, Francine

    2016-01-01

    Blastic plasmacytoid dendritic cell (PDC) neoplasm (BPDCN) is an aggressive hematological malignancy with a poor prognosis that derives from PDCs. No consensus for optimal treatment modalities is available today and the full characterization of this leukemia is still emerging. We identified here a BPDCN-specific transcriptomic profile when compared with those of acute myeloid leukemia and T-acute lymphoblastic leukemia, as well as the transcriptomic signature of primary PDCs. This BPDCN gene signature identified a dysregulation of genes involved in cholesterol homeostasis, some of them being liver X receptor (LXR) target genes. LXR agonist treatment of primary BPDCN cells and BPDCN cell lines restored LXR target gene expression and increased cholesterol efflux via the upregulation of adenosine triphosphate–binding cassette (ABC) transporters, ABCA1 and ABCG1. LXR agonist treatment was responsible for limiting BPDCN cell proliferation and inducing intrinsic apoptotic cell death. LXR activation in BPDCN cells was shown to interfere with 3 signaling pathways associated with leukemic cell survival, namely: NF-κB activation, as well as Akt and STAT5 phosphorylation in response to the BPDCN growth/survival factor interleukin-3. These effects were increased by the stimulation of cholesterol efflux through a lipid acceptor, the apolipoprotein A1. In vivo experiments using a mouse model of BPDCN cell xenograft revealed a decrease of leukemic cell infiltration and BPDCN-induced cytopenia associated with increased survival after LXR agonist treatment. This demonstrates that cholesterol homeostasis is modified in BPDCN and can be normalized by treatment with LXR agonists which can be proposed as a new therapeutic approach. PMID:27702801

  20. Nardosinone protects H9c2 cardiac cells from angiotensin II-induced hypertrophy.

    PubMed

    Du, Meng; Huang, Kun; Gao, Lu; Yang, Liu; Wang, Wen-shuo; Wang, Bo; Huang, Kai; Huang, Dan

    2013-12-01

    Pathological cardiac hypertrophy induced by angiotensin II (AngII) can subsequently give rise to heart failure, a leading cause of mortality. Nardosinone is a pharmacologically active compound extracted from the roots of Nardostachys chinensis, a well-known traditional Chinese medicine. In order to investigate the effects of nardosinone on AngII-induced cardiac cell hypertrophy and the related mechanisms, the myoblast cell line H9c2, derived from embryonic rat heart, was treated with nardosinone (25, 50, 100, and 200 μmol/L) or AngII (1 μmol/L). Then cell surface area and mRNA expression of classical markers of hypertrophy were detected. The related protein levels in PI3K/Akt/mTOR and MEK/ERK signaling pathways were examined by Western blotting. It was found that pretreatment with nardosinone could significantly inhibit the enlargement of cell surface area induced by AngII. The mRNA expression of ANP, BNP and β-MHC was obviously elevated in AngII-treated H9c2 cells, which could be effectively blocked by nardosinone at the concentration of 100 μmol/L. Further study revealed that the protective effects of nardosinone might be mediated by repressing the phosphorylation of related proteins in PI3K/Akt and MEK/ERK signaling pathways. It was suggested that the inhibitory effect of nardosinone on Ang II-induced hypertrophy in H9c2 cells might be mediated by targeting PI3K/Akt and MEK/ERK signaling pathways.

  1. Restoration of Sensitivity in Chemo — Resistant Glioma Cells by Cold Atmospheric Plasma

    PubMed Central

    Köritzer, Julia; Boxhammer, Veronika; Schäfer, Andrea; Shimizu, Tetsuji; Klämpfl, Tobias G.; Li, Yang-Fang; Welz, Christian; Schwenk-Zieger, Sabina; Morfill, Gregor E.; Zimmermann, Julia L.; Schlegel, Jürgen

    2013-01-01

    Glioblastoma (GBM) is the most common and aggressive brain tumor in adults. Despite multimodal treatments including surgery, chemotherapy and radiotherapy the prognosis remains poor and relapse occurs regularly. The alkylating agent temozolomide (TMZ) has been shown to improve the overall survival in patients with malignant gliomas, especially in tumors with methylated promoter of the O6-methylguanine-DNA-methyltransferase (MGMT) gene. However, intrinsic and acquired resistance towards TMZ makes it crucial to find new therapeutic strategies aimed at improving the prognosis of patients suffering from malignant gliomas. Cold atmospheric plasma is a new auspicious candidate in cancer treatment. In the present study we demonstrate the anti-cancer properties of different dosages of cold atmospheric plasma (CAP) both in TMZ-sensitive and TMZ-resistant cells by proliferation assay, immunoblotting, cell cycle analysis, and clonogenicity assay. Importantly, CAP treatment restored the responsiveness of resistant glioma cells towards TMZ therapy. Concomitant treatment with CAP and TMZ led to inhibition of cell growth and cell cycle arrest, thus CAP might be a promising candidate for combination therapy especially for patients suffering from GBMs showing an unfavorable MGMT status and TMZ resistance. PMID:23704990

  2. Assessing cardiac and liver iron overload in chronically transfused patients with sickle cell disease.

    PubMed

    Badawy, Sherif M; Liem, Robert I; Rigsby, Cynthia K; Labotka, Richard J; DeFreitas, R Andrew; Thompson, Alexis A

    2016-11-01

    Transfusional iron overload represents a substantial challenge in the management of patients with sickle cell disease (SCD) who receive chronic or episodic red blood cell transfusions. Iron-induced cardiomyopathy is a leading cause of death in other chronically transfused populations but rarely seen in SCD. Study objectives were to: (i) examine the extent of myocardial and hepatic siderosis using magnetic resonance imaging (MRI) in chronically transfused SCD patients, and (ii) evaluate the relationship between long-term (over the 5 years prior to enrolment) mean serum ferritin (MSF), spot-ferritin values and liver iron content (LIC) measured using MRI and liver biopsy. Thirty-two SCD patients (median age 15 years) with transfusional iron overload were recruited from two U.S. institutions. Long-term MSF and spot-ferritin values significantly correlated with LIC by MRI-R2* (r = 0·77, P < 0·001; r = 0·82, P < 0·001, respectively). LIC by MRI-R2* had strong positive correlation with LIC by liver biopsy (r = 0·98, P < 0·001) but modest inverse correlation with cardiac MRI-T2* (r = -0·41, P = 0·02). Moderate to severe transfusional iron overload in SCD was not associated with aberrations in other measures of cardiac function based on echocardiogram or serum biomarkers. Our results suggest that SCD patients receiving chronic transfusions may not demonstrate significant cardiac iron loading irrespective of ferritin trends, LIC and erythropoiesis suppression.

  3. Inhibition of G9a Histone Methyltransferase Converts Bone Marrow Mesenchymal Stem Cells to Cardiac Competent Progenitors

    PubMed Central

    Yang, Jinpu; Kaur, Keerat; Ong, Li Lin; Eisenberg, Carol A.; Eisenberg, Leonard M.

    2015-01-01

    The G9a histone methyltransferase inhibitor BIX01294 was examined for its ability to expand the cardiac capacity of bone marrow cells. Inhibition of G9a histone methyltransferase by gene specific knockdown or BIX01294 treatment was sufficient to induce expression of precardiac markers Mesp1 and brachyury in bone marrow cells. BIX01294 treatment also allowed bone marrow mesenchymal stem cells (MSCs) to express the cardiac transcription factors Nkx2.5, GATA4, and myocardin when subsequently exposed to the cardiogenic stimulating factor Wnt11. Incubation of BIX01294-treated MSCs with cardiac conditioned media provoked formation of phase bright cells that exhibited a morphology and molecular profile resembling similar cells that normally form from cultured atrial tissue. Subsequent aggregation and differentiation of BIX01294-induced, MSC-derived phase bright cells provoked their cardiomyogenesis. This latter outcome was indicated by their widespread expression of the primary sarcomeric proteins muscle α-actinin and titin. MSC-derived cultures that were not initially treated with BIX01294 exhibited neither a commensurate burst of phase bright cells nor stimulation of sarcomeric protein expression. Collectively, these data indicate that BIX01294 has utility as a pharmacological agent that could enhance the ability of an abundant and accessible stem cell population to regenerate new myocytes for cardiac repair. PMID:26089912

  4. Hybrid Gel Composed of Native Heart Matrix and Collagen Induces Cardiac Differentiation of Human Embryonic Stem Cells without Supplemental Growth Factors

    PubMed Central

    Duan, Yi; Liu, Zen; O'Neill, John; Wan, Leo Q.; Freytes, Donald O.; Vunjak-Novakovic, Gordana

    2011-01-01

    Our goal was to assess the ability of native heart extracellular matrix (ECM) to direct cardiac differentiation of human embryonic stem cells (hESCs) in vitro. In order to probe the effects of cardiac matrix on hESC differentiation, a series of hydrogels was prepared from decellularized ECM from porcine hearts by mixing ECM and collagen type I at varying ratios. Maturation of cardiac function in embryoid bodies formed from hESCs was documented in terms of spontaneous contractile behavior and the mRNA and protein expression of cardiac markers. Hydrogel with high ECM content (75% ECM, 25% collagen, no supplemental soluble factors) increased the fraction of cells expressing cardiac marker troponin T, when compared with either hydrogel with low ECM content (25% ECM, 75% collagen, no supplemental soluble factors) or collagen hydrogel (100% collagen, with supplemental soluble factors). Furthermore, cardiac maturation was promoted in high-ECM content hydrogels, as evidenced by the striation patterns of cardiac troponin I and by upregulation of Cx43 gene. Consistently, high-ECM content hydrogels improved the contractile function of cardiac cells, as evidenced by increased numbers of contracting cells and increased contraction amplitudes. The ability of native ECM hydrogel to induce cardiac differentiation of hESCs without the addition of soluble factors makes it an attractive biomaterial system for basic studies of cardiac development and potentially for the delivery of therapeutic cells into the heart. PMID:21744185

  5. Preclinical Evaluation of the Immunomodulatory Properties of Cardiac Adipose Tissue Progenitor Cells Using Umbilical Cord Blood Mesenchymal Stem Cells: A Direct Comparative Study

    PubMed Central

    Perea-Gil, Isaac; Monguió-Tortajada, Marta; Gálvez-Montón, Carolina; Bayes-Genis, Antoni; Borràs, Francesc E.; Roura, Santiago

    2015-01-01

    Cell-based strategies to regenerate injured myocardial tissue have emerged over the past decade, but the optimum cell type is still under scrutiny. In this context, human adult epicardial fat surrounding the heart has been characterized as a reservoir of mesenchymal-like progenitor cells (cardiac ATDPCs) with potential clinical benefits. However, additional data on the possibility that these cells could trigger a deleterious immune response following implantation are needed. Thus, in the presented study, we took advantage of the well-established low immunogenicity of umbilical cord blood-derived mesenchymal stem cells (UCBMSCs) to comparatively assess the immunomodulatory properties of cardiac ATDPCs in an in vitro allostimulatory assay using allogeneic mature monocyte-derived dendritic cells (MDDCs). Similar to UCBMSCs, increasing amounts of seeded cardiac ATDPCs suppressed the alloproliferation of T cells in a dose-dependent manner. Secretion of proinflammatory cytokines (IL6, TNFα, and IFNγ) was also specifically modulated by the different numbers of cardiac ATDPCs cocultured. In summary, we show that cardiac ATDPCs abrogate T cell alloproliferation upon stimulation with allogeneic mature MDDCs, suggesting that they could further regulate a possible harmful immune response in vivo. Additionally, UCBMSCs can be considered as valuable tools to preclinically predict the immunogenicity of prospective regenerative cells. PMID:25861626

  6. Stimulating endogenous cardiac repair

    PubMed Central

    Finan, Amanda; Richard, Sylvain

    2015-01-01

    The healthy adult heart has a low turnover of cardiac myocytes. The renewal capacity, however, is augmented after cardiac injury. Participants in cardiac regeneration include cardiac myocytes themselves, cardiac progenitor cells, and peripheral stem cells, particularly from the bone marrow compartment. Cardiac progenitor cells and bone marrow stem cells are augmented after cardiac injury, migrate to the myocardium, and support regeneration. Depletion studies of these populations have demonstrated their necessary role in cardiac repair. However, the potential of these cells to completely regenerate the heart is limited. Efforts are now being focused on ways to augment these natural pathways to improve cardiac healing, primarily after ischemic injury but in other cardiac pathologies as well. Cell and gene therapy or pharmacological interventions are proposed mechanisms. Cell therapy has demonstrated modest results and has passed into clinical trials. However, the beneficial effects of cell therapy have primarily been their ability to produce paracrine effects on the cardiac tissue and recruit endogenous stem cell populations as opposed to direct cardiac regeneration. Gene therapy efforts have focused on prolonging or reactivating natural signaling pathways. Positive results have been demonstrated to activate the endogenous stem cell populations and are currently being tested in clinical trials. A potential new avenue may be to refine pharmacological treatments that are currently in place in the clinic. Evidence is mounting that drugs such as statins or beta blockers may alter endogenous stem cell activity. Understanding the effects of these drugs on stem cell repair while keeping in mind their primary function may strike a balance in myocardial healing. To maximize endogenous cardiac regeneration, a combination of these approaches could ameliorate the overall repair process to incorporate the participation of multiple cellular players. PMID:26484341

  7. Channelrhodopsin-2 gene transduced into retinal ganglion cells restores functional vision in genetically blind rats.

    PubMed

    Tomita, Hiroshi; Sugano, Eriko; Isago, Hitomi; Hiroi, Teru; Wang, Zhuo; Ohta, Emi; Tamai, Makoto

    2010-03-01

    To test the hypothesis that transduction of the channelrhodopsin-2 (ChR2) gene, a microbial-type rhodopsin gene, into retinal ganglion cells of genetically blind rats will restore functional vision, we recorded visually evoked potentials and tested the experimental rats for the presence of optomotor responses. The N-terminal fragment of the ChR2 gene was fused to the fluorescent protein Venus and inserted into an adeno-associated virus to make AAV2-ChR2V. AAV2-ChR2V was injected intravitreally into the eyes of 6-month-old dystrophic RCS (rdy/rdy) rats. Visual function was evaluated six weeks after the injection by recording visually evoked potentials (VEPs) and testing optomotor responses. The expression of ChR2V in the retina was investigated histologically. We found that VEPs could not be recorded from 6-month-old dystrophic RCS rats that had not been injected with AAV2-ChR2V. In contrast, VEPs were elicited from RCS rats six weeks after injection with AAV2-ChR2V. The VEPs were recorded at stimulation rates <20Hz, which was the same as that of normal rats. Optomotor responses were also significantly better after the AAV2-ChR2V injection. Expression of ChR2V was observed mainly in the retinal ganglion cells. These findings demonstrate that visual function can be restored in blind rats by transducing the ChR2V gene into retinal ganglion cells.

  8. Rechargeable silver-modified mercuric oxide-zinc cell for cardiac pacemakers.

    PubMed

    Tyers, G F; Hughes, H C; Brownlee, R R; Manley, N J; Gorman, I N

    1976-11-04

    Tests were conducted on rechargeable mercury-zinc pacemaker batteries under simulated and actual biologic conditions, using a variety of discharge rates and charging schedules. In tests on 96 cells at a 6.4 milliampere (ma) discharge, recharging once every 15 months of simulated pacing at a 25 microampere (mua) drain, the earliest cell failure occurred after an equivalent of 50 years of pacing. The mean pacing equivalent for all 96 cells was more than 140 years. In 6.4 ma discharge tests on 24 cells, recharging once every 8 days of simulated pacing, only 1 cell in 24 failed after an equivalent of more than 500 years of pacing (actual time 2 years). In tests on 13 cells pacing at a 200 mua drain without recharging, the simulated mean duration of pacing before total discharge was 4.8 years. Seven other cells at a 200 mua drain with periodic recharging continue to function normally after more than 7 years of actual time, simulating 56 years of pacing at a 25 mua drain. Cardiac pacemakers using the rechargeable mercury-zinc cell have been implanted in animals for more than 2 1/2 years and in patients for more than 1 year with all units continuing to function satisfactorily. It has been demonstrated unequivocally that a rechargeable mercury-zinc pacemaker will function continuously for more than 4 years without recharging and that periodic recharging will extend pacing life far beyond that predicted for lithium and nuclear primary power sources.

  9. Induced pluripotent stem cells and their use in cardiac and neural regenerative medicine.

    PubMed

    Skalova, Stepanka; Svadlakova, Tereza; Shaikh Qureshi, Wasay Mohiuddin; Dev, Kapil; Mokry, Jaroslav

    2015-02-13

    Stem cells are unique pools of cells that are crucial for embryonic development and maintenance of adult tissue homeostasis. The landmark Nobel Prize winning research by Yamanaka and colleagues to induce pluripotency in somatic cells has reshaped the field of stem cell research. The complications related to the usage of pluripotent embryonic stem cells (ESCs) in human medicine, particularly ESC isolation and histoincompatibility were bypassed with induced pluripotent stem cell (iPSC) technology. The human iPSCs can be used for studying embryogenesis, disease modeling, drug testing and regenerative medicine. iPSCs can be diverted to different cell lineages using small molecules and growth factors. In this review we have focused on iPSC differentiation towards cardiac and neuronal lineages. Moreover, we deal with the use of iPSCs in regenerative medicine and modeling diseases like myocardial infarction, Timothy syndrome, dilated cardiomyopathy, Parkinson's, Alzheimer's and Huntington's disease. Despite the promising potential of iPSCs, genome contamination and low efficacy of cell reprogramming remain significant challenges.

  10. Liénard-type models for the simulation of the action potential of cardiac nodal cells

    NASA Astrophysics Data System (ADS)

    Podziemski, P.; Żebrowski, J. J.

    2013-10-01

    Existing models of cardiac cells which include multi-variable cardiac transmembrane current are too complex to simulate the long time dynamical properties of the heart rhythm. The large number of parameters that need to be defined and set for such models make them not only cumbersome to use but also require a large computing power. Consequently, the application of such models for the bedside analysis of heart rate of a specific patient may be difficult. Other ways of modelling need to be investigated. We consider the general problem of developing a model of cardiac pacemaker tissue that allows to combine the investigation of phenomena at a time scale of thousands of heart beats with the ability to reproduce realistic tissue-level characteristics of cell dynamics. We propose a modified van der Pol-Duffing equation-a Liénard-type oscillator-as a phenomenological model for cardiac nodal tissue, with certain important physiological similarities to ion-channel models of cardiac pacemaker cells. The model presented here is specifically designed to qualitatively reproduce mesoscopic characteristics of cell dynamics, including action potential duration (APD) restitution properties, phase response characteristics, and phase space structure. We show that these characteristics agree qualitatively with the extensive ionic models and experimental results in the literature [Anumonwo et al., 1991, [33], Cao et al., 1999, [49], Coster and Celler, 2003, [31], Qu, 2004, [45], Tsalikakis et al., 2007, [32], Inada et al., 2009, [14], Qu et al., 2010, [50

  11. Hepatocyte growth factor (HGF) enhances cardiac commitment of differentiating embryonic stem cells by activating PI3 kinase

    SciTech Connect

    Roggia, Cristiana; Ukena, Christian; Boehm, Michael; Kilter, Heiko . E-mail: kilter@med-in.uni-saarland.de

    2007-03-10

    Hepatocyte growth factor (HGF) is a pleiotropic cytokine promoting proliferation, migration and survival in several cell types. HGF and its cognate receptor c-Met are expressed in cardiac cells during early cardiogenesis, but data concerning its role in cardiac differentiation of embryonic stem cells (ESCs) and the underlying molecular mechanisms involved are limited. In the present study we show that HGF significantly increases the number of beating embryoid bodies of differentiating ESCs without affecting beating frequency. Furthermore, HGF up-regulates the expression of the cardiac-specific transcription factors Nkx 2.5 and GATA-4 and of markers of differentiated cardiomyocytes, i.e. {alpha}-MHC, {beta}-MHC, ANF, MLC2v and Troponin T. The HGF-induced increase in Nkx 2.5 expression was inhibited by co-treatment with the PI3 kinase inhibitors Wortmannin and LY294002, but not by its inactive homolog LY303511, suggesting an involvement of the PI3 kinase/Akt pathway in this effect. We conclude that HGF is an important growth factor involved in cardiac differentiation and/or proliferation of ESCs and may therefore be critical for the in vitro generation of pre- or fully differentiated cardiomyocytes as required for clinical use of embryonic stem cells in cardiac diseases.

  12. Age-Dependent Effect of Pediatric Cardiac Progenitor Cells After Juvenile Heart Failure

    PubMed Central

    Agarwal, Udit; Smith, Amanda W.; French, Kristin M.; Boopathy, Archana V.; George, Alex; Trac, David; Brown, Milton E.; Shen, Ming; Jiang, Rong; Fernandez, Janet D.; Kogon, Brian E.; Kanter, Kirk R.; Alsoufi, Baahaldin; Wagner, Mary B.; Platt, Manu O.

    2016-01-01

    Children with congenital heart diseases have increased morbidity and mortality, despite various surgical treatments, therefore warranting better treatment strategies. Here we investigate the role of age of human pediatric cardiac progenitor cells (hCPCs) on ventricular remodeling in a model of juvenile heart failure. hCPCs isolated from children undergoing reconstructive surgeries were divided into 3 groups based on age: neonate (1 day to 1 month), infant (1 month to 1 year), and child (1 to 5 years). Adolescent athymic rats were subjected to sham or pulmonary artery banding surgery to generate a model of right ventricular (RV) heart failure. Two weeks after surgery, hCPCs were injected in RV musculature noninvasively. Analysis of cardiac function 4 weeks post-transplantation demonstrated significantly increased tricuspid annular plane systolic excursion and RV ejection fraction and significantly decreased wall thickness and fibrosis in rats transplanted with neonatal hCPCs compared with saline-injected rats. Computational modeling and systems biology analysis were performed on arrays and gave insights into potential mechanisms at the microRNA and gene level. Mechanisms including migration and proliferation assays, as suggested by computational modeling, showed improved chemotactic and proliferative capacity of neonatal hCPCs compared with infant/child hCPCs. In vivo immunostaining further suggested increased recruitment of stem cell antigen 1-positive cells in the right ventricle. This is the first study to assess the role of hCPC age in juvenile RV heart failure. Interestingly, the reparative potential of hCPCs is age-dependent, with neonatal hCPCs exerting the maximum beneficial effect compared with infant and child hCPCs. Significance Stem cell therapy for children with congenital heart defects is moving forward, with several completed and ongoing clinical trials. Although there are studies showing how children differ from adults, few focus on the differences

  13. Relaxation of mammalian single cardiac cells after pretreatment with the detergent Brij-58.

    PubMed Central

    Brutsaert, D L; Claes, V A; De Clerck, N M

    1978-01-01

    1. The influence of load and activation on relaxation of heart muscle has been studied. 2. Cardiac cells devoid of functioning sarcolemma were isolated from rat and cat ventricular myocardium. Pretreatment with the detergent Brij-58 destroyed residual sarcoplasmic reticulum function. In order to analyse the mechanical properties of relaxation in these cells, a new miniature transducer was designed which could measure force by feedback sensing (resolution of 1 microgram). Contraction was induced by ionophoretically released calcium ions. Activation, sequestration of calcium and loading conditions could be controlled independently. 3. The time course of relaxation was shown to be governed by the amount of calcium released, and unlike intact preparations from rat or cat heart (but like those from frog), to be independent of load and of alterations in load. 4. We conclude that relaxation of the cardiac contractile system is determined basically by an activation-dependent mechanism, which is masked by load dependence in intact muscle preparations with a well developed calcium sequestering membraneous system. PMID:102766

  14. Epicardial delivery of VEGF and cardiac stem cells guided by 3-dimensional PLLA mat enhancing cardiac regeneration and angiogenesis in acute myocardial infarction.

    PubMed

    Chung, Hye-Jin; Kim, Jong-Tae; Kim, Hee-Jung; Kyung, Hei-Won; Katila, Pramila; Lee, Jeong-Han; Yang, Tae-Hyun; Yang, Young-Il; Lee, Seung-Jin

    2015-05-10

    Congestive heart failure is mostly resulted in a consequence of the limited myocardial regeneration capacity after acute myocardial infarction. Targeted delivery of proangiogenic factors and/or stem cells to the ischemic myocardium is a promising strategy for enhancing their local and sustained therapeutic effects. Herein, we designed an epicardial delivery system of vascular endothelial growth factor (VEGF) and cardiac stem cells (CSCs) using poly(l-lactic acid) (PLLA) mat applied to the acutely infarcted myocardium. The fibrous VEGF-loaded PLLA mat was fabricated by an electrospinning method using PLLA solution emulsified VEGF. This mat not only allowed for sustained release of VEGF for 4weeks but boosted migration and proliferation of both endothelial cells and CSCs in vitro. Furthermore, sustained release of VEGF showed a positive effect on in vitro capillary-like network formation of endothelial cells compared with bolus treatment of VEGF. PLLA mat provided a permissive 3-dimensional (3D) substratum that led to spontaneous cardiomyogenic differentiation of CSCs in vitro. Notably, sustained stimulation by VEGF-loaded PLLA mat resulted in a substantial increase in the expression of proangiogenic mRNAs of CSCs in vitro. The epicardially implanted VEGF-loaded PLLA mat showed modest effects on angiogenesis and cardiomyogenesis in the acutely infarcted hearts. However, co-implantation of VEGF and CSCs using the PLLA mat showed meaningful therapeutic effects on angiogenesis and cardiomyogenesis compared with controls, leading to reduced cardiac remodeling and enhanced global cardiac function. Collectively, the PLLA mat allowed a smart cargo that enabled the sustained release of VEGF and the delivery of CSCs, thereby synergistically inducing angiogenesis and cardiomyogenesis in acute myocardial infarction.

  15. A 3-D cardiac muscle construct for exploring adult marrow stem cell based myocardial regeneration.

    PubMed

    Valarmathi, Mani T; Goodwin, Richard L; Fuseler, John W; Davis, Jeffrey M; Yost, Michael J; Potts, Jay D

    2010-04-01

    Adult bone marrow stromal cells (BMSCs) are capable of differentiating into cardiomyocyte-like cells in vitro and contribute to myocardial regeneration in vivo. Consequently, BMSCs may potentially play a vital role in cardiac repair and regeneration. However, this concept has been limited by inadequate and inconsistent differentiation of BMSCs into cardiomyocytes along with poor survival and integration of neo-cardiomyocytes after implantation into ischemic myocardium. In order to overcome these barriers and to explore adult stem cell based myocardial regeneration, we have developed an in vitro model of three-dimensional (3-D) cardiac muscle using rat ventricular embryonic cardiomyocytes (ECMs) and BMSCs. When ECMs and BMSCs were seeded sequentially onto a 3-D tubular scaffold engineered from topographically aligned type I collagen-fibers and cultured in basal medium for 7, 14, 21, or 28 days, the maturation and co-differentiation into a cardiomyocyte lineage was observed. Phenotypic induction was characterized at morphological, immunological, biochemical and molecular levels. The observed expression of transcripts coding for cardiomyocyte phenotypic markers and the immunolocalization of cardiomyogenic lineage-associated proteins revealed typical expression patterns of neo-cardiomyogenesis. At the biochemical level differentiating cells exhibited appropriate metabolic activity and at the ultrastructural level myofibrillar and sarcomeric organization were indicative of an immature phenotype. Our 3-D co-culture system sustains the ECMs in vitro continuum of differentiation process and simultaneously induces the maturation and differentiation of BMSCs into cardiomyocyte-like cells. Thus, this novel 3-D co-culture system provides a useful in vitro model to investigate the functional role and interplay of developing ECMs and BMSCs during cardiomyogenic differentiation.

  16. Β-blockers treatment of cardiac surgery patients enhances isolation and improves phenotype of cardiosphere-derived cells.

    PubMed

    Chimenti, Isotta; Pagano, Francesca; Cavarretta, Elena; Angelini, Francesco; Peruzzi, Mariangela; Barretta, Antonio; Greco, Ernesto; De Falco, Elena; Marullo, Antonino G M; Sciarretta, Sebastiano; Biondi-Zoccai, Giuseppe; Frati, Giacomo

    2016-11-14

    Β-blockers (BB) are a primary treatment for chronic heart disease (CHD), resulting in prognostic and symptomatic benefits. Cardiac cell therapy represents a promising regenerative treatment and, for autologous cell therapy, the patients clinical history may correlate with the biology of resident progenitors and the quality of the final cell product. This study aimed at uncovering correlations between clinical records of biopsy-donor CHD patients undergoing cardiac surgery and the corresponding yield and phenotype of cardiospheres (CSs) and CS-derived cells (CDCs), which are a clinically relevant population for cell therapy, containing progenitors. We describe a statistically significant association between BB therapy and improved CSs yield and CDCs phenotype. We show that BB-CDCs have a reduced fibrotic-like CD90 + subpopulation, with reduced expression of collagen-I and increased expression of cardiac genes, compared to CDCs from non-BB donors. Moreover BB-CDCs had a distinctive microRNA expression profile, consistent with reduced fibrotic features (miR-21, miR-29a/b/c downregulation), and enhanced regenerative potential (miR-1, miR-133, miR-101 upregulation) compared to non-BB. In vitro adrenergic pharmacological treatments confirmed cytoprotective and anti-fibrotic effects of β1-blocker on CDCs. This study shows anti-fibrotic and pro-commitment effects of BB treatment on endogenous cardiac reparative cells, and suggests adjuvant roles of β-blockers in cell therapy applications.

  17. Β-blockers treatment of cardiac surgery patients enhances isolation and improves phenotype of cardiosphere-derived cells

    PubMed Central

    Chimenti, Isotta; Pagano, Francesca; Cavarretta, Elena; Angelini, Francesco; Peruzzi, Mariangela; Barretta, Antonio; Greco, Ernesto; De Falco, Elena; Marullo, Antonino G. M.; Sciarretta, Sebastiano; Biondi-Zoccai, Giuseppe; Frati, Giacomo

    2016-01-01

    Β-blockers (BB) are a primary treatment for chronic heart disease (CHD), resulting in prognostic and symptomatic benefits. Cardiac cell therapy represents a promising regenerative treatment and, for autologous cell therapy, the patients clinical history may correlate with the biology of resident progenitors and the quality of the final cell product. This study aimed at uncovering correlations between clinical records of biopsy-donor CHD patients undergoing cardiac surgery and the corresponding yield and phenotype of cardiospheres (CSs) and CS-derived cells (CDCs), which are a clinically relevant population for cell therapy, containing progenitors. We describe a statistically significant association between BB therapy and improved CSs yield and CDCs phenotype. We show that BB-CDCs have a reduced fibrotic-like CD90 + subpopulation, with reduced expression of collagen-I and increased expression of cardiac genes, compared to CDCs from non-BB donors. Moreover BB-CDCs had a distinctive microRNA expression profile, consistent with reduced fibrotic features (miR-21, miR-29a/b/c downregulation), and enhanced regenerative potential (miR-1, miR-133, miR-101 upregulation) compared to non-BB. In vitro adrenergic pharmacological treatments confirmed cytoprotective and anti-fibrotic effects of β1-blocker on CDCs. This study shows anti-fibrotic and pro-commitment effects of BB treatment on endogenous cardiac reparative cells, and suggests adjuvant roles of β-blockers in cell therapy applications. PMID:27841293

  18. A fetal human heart cardiac-inducing RNA (CIR) promotes the differentiation of stem cells into cardiomyocytes.

    PubMed

    Kochegarov, Andrei; Moses-Arms, Ashley; Lemanski, Larry F

    2015-08-01

    A specific human fetal heart RNA has been discovered, which has the ability to induce myocardial cell formation from mouse embryonic and human-induced pluripotent stem cells in culture. In this study, commercially obtained RNA from human fetal heart was cloned, sequenced, and synthesized using standard laboratory approaches. Molecular analyses of the specific fetal cardiac-inducing RNA (CIR), revealed that it is a fragment of N-sulfoglucosaminesulfohydrolase and the caspase recruitment domain family member 14 precursor. Stem cells transfected with CIRs often form into spindle-shaped cells characteristic of cardiomyocytes,and express the cardiac-specific contractile protein marker, troponin-T, in addition to tropomyosin and α-actinin as detected by immunohistochemical staining. Expression of these contractile proteins showed organization into sarcomeric myofibrils characteristic of striated cardiac muscle cells. Computer analyses of the RNA secondary structures of the active CIR show significant similarities to a RNA from salamander or myofibril-inducing RNA (MIR), which also promotes non-muscle cells to differentiate into cardiac muscle. Thus, these two RNAs, salamander MIR and the newly discovered human-cloned CIR reported here, appear to have evolutionarily conserved secondary structures suggesting that both play major roles in vertebrate heart development and, particularly, in the differentiation of cardiomyocytes from non-muscle cells during development.

  19. Roles of store-operated Ca2+ channels in regulating cell cycling and migration of human cardiac c-kit+ progenitor cells.

    PubMed

    Che, Hui; Li, Gang; Sun, Hai-Ying; Xiao, Guo-Sheng; Wang, Yan; Li, Gui-Rong

    2015-11-15

    Cardiac c-kit(+) progenitor cells are important for maintaining cardiac homeostasis and can potentially contribute to myocardial repair. However, cellular physiology of human cardiac c-kit(+) progenitor cells is not well understood. The present study investigates the functional store-operated Ca(2+) entry (SOCE) channels and the potential role in regulating cell cycling and migration using confocal microscopy, RT-PCR, Western blot, coimmunoprecipitation, cell proliferation, and migration assays. We found that SOCE channels mediated Ca(2+) influx, and TRPC1, STIM1, and Orai1 were involved in the formation of SOCE channels in human cardiac c-kit(+) progenitor cells. Silencing TRPC1, STIM1, or Orai1 with the corresponding siRNA significantly reduced the Ca(2+) signaling through SOCE channels, decreased cell proliferation and migration, and reduced expression of cyclin D1, cyclin E, and/or p-Akt. Our results demonstrate the novel information that Ca(2+) signaling through SOCE channels regulates cell cycling and migration via activating cyclin D1, cyclin E, and/or p-Akt in human cardiac c-kit(+) cells.

  20. Synergistic plasticity of intrinsic conductance and electrical coupling restores synchrony in an intact motor network.

    PubMed

    Lane, Brian J; Samarth, Pranit; Ransdell, Joseph L; Nair, Satish S; Schulz, David J

    2016-08-23

    Motor neurons of the crustacean cardiac ganglion generate virtually identical, synchronized output despite the fact that each neuron uses distinct conductance magnitudes. As a result of this variability, manipulations that target ionic conductances have distinct effects on neurons within the same ganglion, disrupting synchronized motor neuron output that is necessary for proper cardiac function. We hypothesized that robustness in network output is accomplished via plasticity that counters such destabilizing influences. By blocking high-threshold K(+) conductances in motor neurons within the ongoing cardiac network, we discovered that compensation both resynchronized the network and helped restore excitability. Using model findings to guide experimentation, we determined that compensatory increases of both GA and electrical coupling restored function in the network. This is one of the first direct demonstrations of the physiological regulation of coupling conductance in a compensatory context, and of synergistic plasticity across cell- and network-level mechanisms in the restoration of output.

  1. Guttiferone K suppresses cell motility and metastasis of hepatocellular carcinoma by restoring aberrantly reduced profilin 1

    PubMed Central

    Xie, Jianling; Wang, Hua; Xie, Chanlu; Lee, C.Soon; Fahey, Paul; Dong, Qihan; Xu, Hongxi

    2016-01-01

    Hepatocellular carcinoma (HCC) is an aggressive malignancy and the 5-year survival rate of advanced HCC is < 10%. Guttiferone K (GUTK) isolated from the Garcinia genus inhibited HCC cells migration and invasion in vitro and metastasis in vivo without apparent toxicity. Proteomic analysis revealed that actin-binding protein profilin 1 (PFN1) was markedly increased in the presence of GUTK. Over-expression of PFN1 mimicked the effect of GUTK on HCC cell motility and metastasis. The effect of GUTK on cell motility was diminished when PFN1 was over-expressed or silenced. Over-expression of PFN1 or incubation with GUTK decreased F-actin levels and the expression of proteins involved in actin nucleation, branching and polymerization. Moreover, a reduction of PFN1 protein levels was common in advanced human HCC and associated with poor survival rate. In conclusion, GUTK effectively suppresses the motility and metastasis of HCC cells mainly by restoration of aberrantly reduced PFN1 protein expression. PMID:27494863

  2. Cyclic AMP restores a normal phenotype to sis oncogene transformed cells and inhibits inositol phospholipid turnover

    SciTech Connect

    Murphy, S.K.; Lazarus, A.; Pendergas, M.; Lockwood, A.H.

    1987-05-01

    The sis oncogene encodes the A chain of platelet-derived growth factor (PDGF). NIH3T3 fibroblasts transfected with the cloned sis oncogene display a malignant phenotype and have enhanced turnover of the regulatory phospholipid phosphatidylinositol 4,5 biphosphate (PIP2). They have found that elevation of intracellular cyclic AMP can restore many aspects of normal growth and morphology to sis-transformed cells. Cells rapidly become less refractile, flatten on the substratum, develop actomyosin bundles, and acquire a more tranquil membrane. Growth rate and saturation density are reduced. Cultures become contact-inhibited and, at confluence, assume a normal fibrobastic morphology. The ability to grow in low serum or suspension is lost. Following addition of 8-Br-cAMP, cellular levels of PIP and PIP2 increase to those in untransformed cells. Concurrently, the steady-state levels of inositol phosphates are reduced to normal values. They have found a similar effect of cAMP on inositol phospholipid metabolism in cells transformed by the human H-ras oncogene. These results suggest that cAMP, acting through the cAMP-dependent protein kinase, antagonizes ras and sis oncogene expression by inhibiting polyphosphoinositide turnover. Such action might occur by phosphorylation of the PDGF (sis) receptor or of a ras-stimulated phospholipase C.

  3. Human Umbilical Cord Blood Cells Restore Brain Damage Induced Changes in Rat Somatosensory Cortex

    PubMed Central

    Geißler, Maren; Dinse, Hubert R.; Neuhoff, Sandra; Kreikemeier, Klaus; Meier, Carola

    2011-01-01

    Intraperitoneal transplantation of human umbilical cord blood (hUCB) cells has been shown to reduce sensorimotor deficits after hypoxic ischemic brain injury in neonatal rats. However, the neuronal correlate of the functional recovery and how such a treatment enforces plastic remodelling at the level of neural processing remains elusive. Here we show by in-vivo recordings that hUCB cells have the capability of ameliorating the injury-related impairment of neural processing in primary somatosensory cortex. Intact cortical processing depends on a delicate balance of inhibitory and excitatory transmission, which is disturbed after injury. We found that the dimensions of cortical maps and receptive fields, which are significantly altered after injury, were largely restored. Additionally, the lesion induced hyperexcitability was no longer observed in hUCB treated animals as indicated by a paired-pulse behaviour resembling that observed in control animals. The beneficial effects on cortical processing were reflected in an almost complete recovery of sensorimotor behaviour. Our results demonstrate that hUCB cells reinstall the way central neurons process information by normalizing inhibitory and excitatory processes. We propose that the intermediate level of cortical processing will become relevant as a new stage to investigate efficacy and mechanisms of cell therapy in the treatment of brain injury. PMID:21673795

  4. Human umbilical cord blood cells restore brain damage induced changes in rat somatosensory cortex.

    PubMed

    Geissler, Maren; Dinse, Hubert R; Neuhoff, Sandra; Kreikemeier, Klaus; Meier, Carola

    2011-01-01

    Intraperitoneal transplantation of human umbilical cord blood (hUCB) cells has been shown to reduce sensorimotor deficits after hypoxic ischemic brain injury in neonatal rats. However, the neuronal correlate of the functional recovery and how such a treatment enforces plastic remodelling at the level of neural processing remains elusive. Here we show by in-vivo recordings that hUCB cells have the capability of ameliorating the injury-related impairment of neural processing in primary somatosensory cortex. Intact cortical processing depends on a delicate balance of inhibitory and excitatory transmission, which is disturbed after injury. We found that the dimensions of cortical maps and receptive fields, which are significantly altered after injury, were largely restored. Additionally, the lesion induced hyperexcitability was no longer observed in hUCB treated animals as indicated by a paired-pulse behaviour resembling that observed in control animals. The beneficial effects on cortical processing were reflected in an almost complete recovery of sensorimotor behaviour. Our results demonstrate that hUCB cells reinstall the way central neurons process information by normalizing inhibitory and excitatory processes. We propose that the intermediate level of cortical processing will become relevant as a new stage to investigate efficacy and mechanisms of cell therapy in the treatment of brain injury.

  5. TGF-{beta}{sub 1}-induced cardiac myofibroblasts are nonproliferating functional cells carrying DNA damages

    SciTech Connect

    Petrov, Victor V. Pelt, Jos F. van; Vermeesch, Joris R.; Van Duppen, Viktor J.; Vekemans, Katrien; Fagard, Robert H.; Lijnen, Paul J.

    2008-04-15

    TGF-{beta}{sub 1} induces differentiation and total inhibition of cardiac MyoFb cell division and DNA synthesis. These effects of TGF-{beta}{sub 1} are irreversible. Inhibition of MyoFb proliferation is accompanied with the expression of Smad1, Mad1, p15Ink4B and total inhibition of telomerase activity. Surprisingly, TGF-{beta}{sub 1}-activated MyoFbs are growth-arrested not only at G1-phase but also at S-phase of the cell cycle. Staining with TUNEL indicates that these cells carry DNA damages. However, the absolute majority of MyoFbs are non-apoptotic cells as established with two apoptosis-specific methods, flow cytometry and caspase-dependent cleavage of cytokeratin 18. Expression in MyoFbs of proliferative cell nuclear antigen even in the absence of serum confirms that these MyoFbs perform repair of DNA damages. These results suggest that TGF-{beta}{sub 1}-activated MyoFbs can be growth-arrested by two checkpoints, the G1/S checkpoint, which prevents cells from entering S-phase and the intra-S checkpoint, which is activated by encountering DNA damage during the S phase or by unrepaired damage that escapes the G1/S checkpoint. Despite carrying of the DNA damages TGF-{beta}{sub 1}-activated MyoFbs are highly functional cells producing lysyl oxidase and contracting the collagen matrix.

  6. Interleukin-34 restores blood-brain barrier integrity by upregulating tight junction proteins in endothelial cells.

    PubMed

    Jin, Shijie; Sonobe, Yoshifumi; Kawanokuchi, Jun; Horiuchi, Hiroshi; Cheng, Yi; Wang, Yue; Mizuno, Tetsuya; Takeuchi, Hideyuki; Suzumura, Akio

    2014-01-01

    Interleukin-34 (IL-34) is a newly discovered cytokine as an additional ligand for colony stimulating factor-1 receptor (CSF1R), and its functions are expected to overlap with colony stimulating factor-1/macrophage-colony stimulating factor. We have previously shown that the IL-34 is primarily produced by neurons in the central nervous system (CNS) and induces proliferation and neuroprotective properties of microglia which express CSF1R. However, the functions of IL-34 in the CNS are still elucidative. Here we show that CNS capillary endothelial cells also express CSF1R. IL-34 protected blood-brain barrier integrity by restored expression levels of tight junction proteins, which were downregulated by pro-inflammatory cytokines. The novel function of IL-34 on the blood-brain barrier may give us a clue for new therapeutic strategies in neuroinflammatory and neurodegenerative diseases such as multiple sclerosis and Alzheimer's disease.

  7. Interleukin-34 Restores Blood–Brain Barrier Integrity by Upregulating Tight Junction Proteins in Endothelial Cells

    PubMed Central

    Jin, Shijie; Sonobe, Yoshifumi; Kawanokuchi, Jun; Horiuchi, Hiroshi; Cheng, Yi; Wang, Yue; Mizuno, Tetsuya; Takeuchi, Hideyuki; Suzumura, Akio

    2014-01-01

    Interleukin-34 (IL-34) is a newly discovered cytokine as an additional ligand for colony stimulating factor-1 receptor (CSF1R), and its functions are expected to overlap with colony stimulating factor-1/macrophage-colony stimulating factor. We have previously shown that the IL-34 is primarily produced by neurons in the central nervous system (CNS) and induces proliferation and neuroprotective properties of microglia which express CSF1R. However, the functions of IL-34 in the CNS are still elucidative. Here we show that CNS capillary endothelial cells also express CSF1R. IL-34 protected blood–brain barrier integrity by restored expression levels of tight junction proteins, which were downregulated by pro-inflammatory cytokines. The novel function of IL-34 on the blood–brain barrier may give us a clue for new therapeutic strategies in neuroinflammatory and neurodegenerative diseases such as multiple sclerosis and Alzheimer's disease. PMID:25535736

  8. Satellite cell proliferation is reduced in muscles of obese Zucker rats but restored with loading.

    PubMed

    Peterson, Jonathan M; Bryner, Randall W; Alway, Stephen E

    2008-08-01

    The obese Zucker rat (OZR) is a model of metabolic syndrome, which has lower skeletal muscle size than the lean Zucker rat (LZR). Because satellite cells are essential for postnatal muscle growth, this study was designed to determine whether reduced satellite cell proliferation contributes to reduced skeletal mass in OZR vs. LZR. Satellite cell proliferation was determined by a constant-release 5-bromo-2-deoxyuridine (BrdU) pellet that was placed subcutaneously in each animal. Satellite cell proliferation, as determined by BrdU incorporation, was significantly attenuated in control soleus and plantaris muscles of the OZR compared with that shown in the LZR. To determine whether this attenuation of satellite cell activity could be rescued in OZR muscles, soleus and gastrocnemius muscles were denervated, placing a compensatory load on the plantaris muscle. In the LZR and the OZR after 21 days of loading, increases of approximately 25% and approximately 30%, respectively, were shown in plantaris muscle wet weight compared with that shown in the contralateral control muscle. The number of BrdU-positive nuclei increased similarly in loaded plantaris muscles from LZR and OZR. Myogenin, MyoD, and Akt protein expressions were lower in control muscles of OZR than in those of the LZR, but they were all elevated to similar levels in the loaded plantaris muscles of OZR and LZR. These data indicate that metabolic syndrome may reduce satellite cell proliferation, and this may be a factor that contributes to the reduced mass in control muscles of OZR; however, satellite cell proliferation can be restored with compensatory loading in OZR.

  9. Camkii-Dependent Phosphorylation of Cardiac Ryanodine Receptors Regulates Cell Death In Cardiac Ischemia/Reperfusion Injury

    PubMed Central

    Di Carlo, Mariano N.; Said, Matilde; Ling, Haiyun; Valverde, Carlos A.; De Giusti, Verónica; Sommese, Leandro; Palomeque, Julieta; Aiello, Alejandro E.; Skapura, Darlene G.; Rinaldi, Gustavo; Respress, Jonathan L.; Brown, Joan Heller; Wehrens, Xander H.T.; Salas, Margarita A.; Mattiazzi, Alicia

    2014-01-01

    Ca2+-Calmodulin kinase II (CaMKII) activation is deleterious in cardiac ischemia/reperfusion (I/R). Moreover, inhibition of CaMKII-dependent phosphorylations at the sarcoplasmic reticulum (SR) prevents CaMKII-induced I/R damage. However, the downstream targets of CaMKII at the SR level, responsible for this detrimental effect, remain unclear. In the present study we aimed to dissect the role of the two main substrates of CaMKII at the SR level, phospholamban (PLN) and ryanodine receptors (RyR2), in CaMKII-dependent I/R injury. In mouse hearts subjected to global I/R (45/120 min), phosphorylation of the primary CaMKII sites, S2814 on cardiac RyR2 and of T17 on PLN, significantly increased at the onset of reperfusion whereas PKA-dependent phosphorylation of RyR2 and PLN did not change. Similar results were obtained in vivo, in mice subjected to regional myocardial I/R (1/24 hrs). Knock-in mice with an inactivated serine 2814 phosphorylation site on RyR2 (S2814A), significantly improved post-ischemic mechanical recovery, reduced infarct size and decreased apoptosis. Conversely, knock-in mice, in which CaMKII site of RyR2 is constitutively activated (S2814D), significantly increased infarct size and exacerbated apoptosis. In S2814A and S2814D mice subjected to regional myocardial ischemia, infarct size was also decreased and increased respectively. Transgenic mice with double-mutant non-phosphorylatable PLN (S16A/T17A) in the PLN knockout background (PLNDM) also showed significantly increased post-ischemic cardiac damage. This effect cannot be attributed to PKA-dependent PLN phosphorylation and was not due to the enhanced L-type Ca2+ current, present in these mice. Our results reveal a major role for the phosphorylation of S2814 site on RyR2 in CaMKII-dependent I/R cardiac damage. In contrast, they showed that CaMKII-dependent increase in PLN phosphorylation during reperfusion opposes rather than contributes to I/R damage. PMID:24949568

  10. Paracrine Effects of Adipose-Derived Stem Cells on Matrix Stiffness-Induced Cardiac Myofibroblast Differentiation via Angiotensin II Type 1 Receptor and Smad7.

    PubMed

    Yong, Kar Wey; Li, Yuhui; Liu, Fusheng; Bin Gao; Lu, Tian Jian; Wan Abas, Wan Abu Bakar; Wan Safwani, Wan Kamarul Zaman; Pingguan-Murphy, Belinda; Ma, Yufei; Xu, Feng; Huang, Guoyou

    2016-10-05

    Human mesenchymal stem cells (hMSCs) hold great promise in cardiac fibrosis therapy, due to their potential ability of inhibiting cardiac myofibroblast differentiation (a hallmark of cardiac fibrosis). However, the mechanism involved in their effects remains elusive. To explore this, it is necessary to develop an in vitro cardiac fibrosis model that incorporates pore size and native tissue-mimicking matrix stiffness, which may regulate cardiac myofibroblast differentiation. In the present study, collagen coated polyacrylamide hydrogel substrates were fabricated, in which the pore size was adjusted without altering the matrix stiffness. Stiffness is shown to regulate cardiac myofibroblast differentiation independently of pore size. Substrate at a stiffness of 30 kPa, which mimics the stiffness of native fibrotic cardiac tissue, was found to induce cardiac myofibroblast differentiation to create in vitro cardiac fibrosis model. Conditioned medium of hMSCs was applied to the model to determine its role and inhibitory mechanism on cardiac myofibroblast differentiation. It was found that hMSCs secrete hepatocyte growth factor (HGF) to inhibit cardiac myofibroblast differentiation via downregulation of angiotensin II type 1 receptor (AT1R) and upregulation of Smad7. These findings would aid in establishment of the therapeutic use of hMSCs in cardiac fibrosis therapy in future.

  11. Paracrine Effects of Adipose-Derived Stem Cells on Matrix Stiffness-Induced Cardiac Myofibroblast Differentiation via Angiotensin II Type 1 Receptor and Smad7

    PubMed Central

    Yong, Kar Wey; Li, Yuhui; Liu, Fusheng; Bin Gao; Lu, Tian Jian; Wan Abas, Wan Abu Bakar; Wan Safwani, Wan Kamarul Zaman; Pingguan-Murphy, Belinda; Ma, Yufei; Xu, Feng; Huang, Guoyou

    2016-01-01

    Human mesenchymal stem cells (hMSCs) hold great promise in cardiac fibrosis therapy, due to their potential ability of inhibiting cardiac myofibroblast differentiation (a hallmark of cardiac fibrosis). However, the mechanism involved in their effects remains elusive. To explore this, it is necessary to develop an in vitro cardiac fibrosis model that incorporates pore size and native tissue-mimicking matrix stiffness, which may regulate cardiac myofibroblast differentiation. In the present study, collagen coated polyacrylamide hydrogel substrates were fabricated, in which the pore size was adjusted without altering the matrix stiffness. Stiffness is shown to regulate cardiac myofibroblast differentiation independently of pore size. Substrate at a stiffness of 30 kPa, which mimics the stiffness of native fibrotic cardiac tissue, was found to induce cardiac myofibroblast differentiation to create in vitro cardiac fibrosis model. Conditioned medium of hMSCs was applied to the model to determine its role and inhibitory mechanism on cardiac myofibroblast differentiation. It was found that hMSCs secrete hepatocyte growth factor (HGF) to inhibit cardiac myofibroblast differentiation via downregulation of angiotensin II type 1 receptor (AT1R) and upregulation of Smad7. These findings would aid in establishment of the therapeutic use of hMSCs in cardiac fibrosis therapy in future. PMID:27703175

  12. Cell delivery and tracking in post-myocardial infarction cardiac stem cell therapy: an introduction for clinical researchers.

    PubMed

    Wei, Heming; Ooi, Ting Huay; Tan, Genevieve; Lim, Sze Yun; Qian, Ling; Wong, Philip; Shim, Winston

    2010-01-01

    Stem cell-based therapy for patients with post-infarct heart failure is a relatively new and revolutionary concept in cardiology. Despite the encouraging results from pre-clinical studies, outcomes from most clinical trials remain moderately positive while the clinical benefits are largely attributed to transplanted cell-associated paracrine effects in stimulating angiogenesis and protecting endogenous cardiomyocytes. This scenario indicates that there may be a considerably protracted iterative process of conceptual and procedural refinement before true clinical benefits can be fully materialized. At present, many pressing questions regarding cell therapy remain unanswered. In addition to the primary interest in determining the ideal type of stem cells with best cardiogenic potential in vitro and in vivo, there are growing concerns on the impact of the host cardiac milieu on the transplanted cells, including their survival, migration, engraftment, and trans-differentiation as well as contribution to left ventricular function. Effective cell delivery and tracking methods are central to the unraveling of these questions. To date, cell-delivery modalities are yet to be optimized and strategies for safe and effective assessment of cells transplanted in the recipients are to be established. In this review, we discuss cell delivery and tracking modalities that are adopted in the current pre-clinical and clinical studies. We further discussed emerging technologies that are poised to impact the success of cell therapy.

  13. Dinaciclib potently suppresses MCL-1 and selectively induces the cell death in human iPS cells without affecting the viability of cardiac tissue

    PubMed Central

    Alsayegh, Khaled; Matsuura, Katsuhisa; Sekine, Hidekazu; Shimizu, Tatsuya

    2017-01-01

    Induced pluripotent stem (iPS) cells hold great potential for being a major source of cells for regenerative medicine. One major issue that hinders their advancement to clinic is the persistence of undifferentiated iPS cells in iPS-derived tissue. In this report, we show that the CDKs inhibitor, Dinaciclib, selectively eliminates iPS cells without affecting the viability of cardiac cells. We found that low nanomolar concentration of dinaciclib increased DNA damage and p53 protein levels in iPSCs. This was accompanied by negative regulation of the anti-apoptotic protein MCL-1. Gene knockdown experiments revealed that p53 downregulation only increased the threshold of dinaciclib induced apoptosis in iPS cells. Dinaciclib also inhibited the phosphorylation of Serine 2 of the C-terminal domain of RNA Polyemrase II through CDK9 inhibition. This resulted in the inhibition of transcription of MCL-1 and the pluripotency genes, NANOG and c-MYC. Even though dinaciclib caused a slight downregulation of MCL-1 in iPS-derived cardiac cells, the viability of the cells was not significantly affected, and beating iPS-derived cardiac cell sheet could still be fabricated. These findings suggest a difference in tolerance of MCL-1 downregulation between iPSCs and iPS-derived cardiac cells which could be exploited to eliminate remaining iPS cells in bioengineered cell sheet tissues. PMID:28361959

  14. MiRNA-Sequence Indicates That Mesenchymal Stem Cells and Exosomes Have Similar Mechanism to Enhance Cardiac Repair

    PubMed Central

    Zhang, Yu; Lan, Beibei; Wang, Juanjuan; Zhang, Zhiwei; Zhang, Lulu; Xiao, Pengli; Meng, Qingyou; Geng, Yong-jian; Yu, Xi-yong

    2017-01-01

    Mesenchymal stem cells (MSCs) repair infarcted heart through paracrine mechanism. We sought to compare the effectiveness of MSCs and MSC-derived exosomes (MSC-Exo) in repairing infarcted hearts and to identify how MSC-Exo mediated cardiac repair is regulated. In a rat myocardial infarction model, we found that MSC-Exo inhibited cardiac fibrosis, inflammation, and improved cardiac function. The beneficial effects of MSC-Exo were significantly superior compared to that of MSCs. To explore the potential mechanisms underlying MSC-Exo's effects, we performed several in vitro experiments and miRNA-sequence analysis. MSC-Exo stimulated cardiomyocyte H9C2 cell proliferation, inhibited apoptosis induced by H2O2, and inhibited TGF-β induced transformation of fibroblast cell into myofibroblast. Importantly, novel miRNA sequencing results indicated that MSC-Exo and MSCs have similar miRNA expression profile, which could be one of the reasons that MSC-Exo can replace MSCs for cardiac repair. In addition, the expression of several miRNAs from MSC-Exo was significantly different from that of MSCs, which may explain why MSC-Exo has better therapeutic effect than MSCs. In conclusion, this study demonstrates that MSC-Exo could be used alone to promote cardiac repair and are superior to MSCs in repairing injured myocardium. PMID:28203568

  15. Complex-periodic spiral waves in confluent cardiac cell cultures induced by localized inhomogeneities

    NASA Astrophysics Data System (ADS)

    Hwang, Seong-min; Kim, Tae Yun; Lee, Kyoung J.

    2005-07-01

    Spatiotemporal wave activities in excitable heart tissues have long been the subject of numerous studies because they underlie different forms of cardiac arrhythmias. In particular, understanding the dynamics and the instabilities of spiral waves have become very important because they can cause reentrant tachycardia and their subsequent transitions to fibrillation. Although many aspects of cardiac spiral waves have been investigated through experiments and model simulations, their complex properties are far from well understood. Here, we show that intriguing complex-periodic (such as period-2, period-3, period-4, or aperiodic) spiral wave states can arise in monolayer tissues of cardiac cell culture in vitro, and demonstrate that these different dynamic states can coexist with abrupt and spontaneous transitions among them without any change in system parameters; in other words, the medium supports multistability. Based on extensive image data analysis, we have confirmed that these spiral waves are driven by their tips tracing complex orbits whose unusual, meandering shapes are formed by delicate interplay between localized conduction blocks and nonlinear properties of the culture medium. Author contributions: S.-m.H. and K.J.L. designed research; S.-m.H. and T.Y.K. performed research; S.-m.H. contributed new reagents/analytic tools; S.-m.H., T.Y.K., and K.J.L. analyzed data; and S.-m.H. and K.J.L. wrote the paper.This paper was submitted directly (Track II) to the PNAS office.Abbreviations: IBI, interbeat interval; P-n, period-n.

  16. Estrogen inhibits mast cell chymase release to prevent pressure overload-induced adverse cardiac remodeling.

    PubMed

    Li, Jianping; Jubair, Shaiban; Janicki, Joseph S

    2015-02-01

    Estrogen regulation of myocardial chymase and chymase effects on cardiac remodeling are unknown. To test the hypothesis that estrogen prevents pressure overload-induced adverse cardiac remodeling by inhibiting mast cell (MC) chymase release, transverse aortic constriction or sham surgery was performed in 7-week-old intact and ovariectomized (OVX) rats. Three days before creating the constriction, additional groups of OVX rats began receiving 17β-estradiol, a chymase inhibitor, or a MC stabilizer. Left ventricular function, cardiomyocyte size, collagen volume fraction, MC density and degranulation, and myocardial and plasma chymase levels were assessed 18 days postsurgery. Aortic constriction resulted in ventricular hypertrophy in intact and OVX groups, whereas collagen volume fraction was increased only in OVX rats. Chymase protein content was increased by aortic constriction in the intact and OVX groups, with the magnitude of the increase being greater in OVX rats. MC density and degranulation, plasma chymase levels, and myocardial active transforming growth factor-β1 levels were increased by aortic constriction only in OVX rats. Estrogen replacement markedly attenuated the constriction-increased myocardial chymase, MC density and degranulation, plasma chymase, and myocardial active transforming growth factor-β1, as well as prevented ventricular hypertrophy and increased collagen volume fraction. Chymostatin attenuated the aortic constriction-induced ventricular hypertrophy and collagen volume fraction in the OVX rats similar to that achieved by estrogen replacement. Nedocromil yielded similar effects, except for the reduction of chymase content. We conclude that the estrogen-inhibited release of MC chymase is responsible for the cardioprotection against transverse aortic constriction-induced adverse cardiac remodeling.

  17. Myocardial regeneration by activation of multipotent cardiac stem cells in ischemic heart failure

    NASA Astrophysics Data System (ADS)

    Urbanek, Konrad; Torella, Daniele; Sheikh, Farooq; de Angelis, Antonella; Nurzynska, Daria; Silvestri, Furio; Beltrami, C. Alberto; Bussani, Rossana; Beltrami, Antonio P.; Quaini, Federico; Bolli, Roberto; Leri, Annarosa; Kajstura, Jan; Anversa, Piero

    2005-06-01

    In this study, we tested whether the human heart possesses a cardiac stem cell (CSC) pool that promotes regeneration after infarction. For this purpose, CSC growth and senescence were measured in 20 hearts with acute infarcts, 20 hearts with end-stage postinfarction cardiomyopathy, and 12 control hearts. CSC number increased markedly in acute and, to a lesser extent, in chronic infarcts. CSC growth correlated with the increase in telomerase-competent dividing CSCs from 1.5% in controls to 28% in acute infarcts and 14% in chronic infarcts. The CSC mitotic index increased 29-fold in acute and 14-fold in chronic infarcts. CSCs committed to the myocyte, smooth muscle, and endothelial cell lineages increased 85-fold in acute infarcts and 25-fold in chronic infarcts. However, p16INK4a-p53-positive senescent CSCs also increased and were 10%, 18%, and 40% in controls, acute infarcts, and chronic infarcts, respectively. Old CSCs had short telomeres and apoptosis involved 0.3%, 3.8%, and 9.6% of CSCs in controls, acute infarcts, and chronic infarcts, respectively. These variables reduced the number of functionally competent CSCs from 26,000/cm3 of viable myocardium in acute to 7,000/cm3 in chronic infarcts, respectively. In seven acute infarcts, foci of spontaneous myocardial regeneration that did not involve cell fusion were identified. In conclusion, the human heart possesses a CSC compartment, and CSC activation occurs in response to ischemic injury. The loss of functionally competent CSCs in chronic ischemic cardiomyopathy may underlie the progressive functional deterioration and the onset of terminal failure. cardiac progenitor cells | human heart | myocardial infarction

  18. Essential role of PDL1 expression on nonhematopoietic donor cells in acquired tolerance to vascularized cardiac allografts.

    PubMed

    Riella, L V; Watanabe, T; Sage, P T; Yang, J; Yeung, M; Azzi, J; Vanguri, V; Chandraker, A; Sharpe, A H; Sayegh, M H; Najafian, N

    2011-04-01

    The PD1:PDL1 pathway is an essential negative costimulatory pathway that plays a key role in regulating the alloimune response. PDL1 is expressed not only on antigen-presenting cells (APCs) but also cardiac endothelium. In this study, we investigated the importance of PDL1 expression on donor cardiac allograft in acquired transplantation tolerance in a fully MHC-mismatched model. We generated PDL1 chimeric mice on B6 background that expressed PDL1 on either hematopoietic cells or nonhematopoietic cells of the heart. Sham animals were used as controls. These hearts were then transplanted into BALB/c recipients and treated with CTLA4-Ig to induce tolerance. Cardiac endothelium showed significant expression of PDL1, which was upregulated upon transplantation. While the absence of PDL1 on hematopoietic cells of the heart resulted in delayed rejection and prevented long-term tolerance in most but not all recipients, we observed an accelerated and early graft rejection of all donor allografts that lacked PDL1 on the endothelium. Moreover, PDL1-deficient endothelium hearts had significant higher frequency of IFN-γ-producing alloreactive cells as well as higher frequency of CD8(+) effector T cells. These findings demonstrate that PDL1 expression mainly on donor endothelium is functionally important in a fully allogeneic mismatched model for the induction of cardiac allograft tolerance.

  19. Encapsulation of cardiac stem cells in superoxide dismutase-loaded alginate prevents doxorubicin-mediated toxicity.

    PubMed

    Liu, Ting Chu Ken; Ismail, Siti; Brennan, Orlaith; Hastings, Conn; Duffy, Garry P

    2013-04-01

    Anthracyclines are powerful drugs available for the treatment of neoplastic diseases. Unfortunately, these chemotherapy agents cause cardiomyopathy and congestive heart failure. Doxorubicin (DOX) is a widely used anthracycline and evidence indicates that DOX-induced cardiotoxicity can be viewed as a stem cell disease, whereby the formation of reactive oxygen species (ROS) by DOX is seen to predominantly hinder cardiac stem cell (CSC) regenerative capability. Acute, early-onset and late-onset cardiotoxicity have been described and this may be reversible by the local administration of CSCs, which regenerate myocardial tissue and rescue the failing heart. CSCs are, however, particularly sensitive to oxidative stress and die rapidly by apoptosis in such adverse conditions. Therefore, this study aims to enhance CSC survival by encapsulation in an alginate hydrogel formulation containing superoxide dismutase (SOD), a reactive oxygen species scavenger. Cell survival was qualitatively and quantitatively assessed by fluorescent microscopy and assays measuring metabolic activity, cell viability, cytotoxicity and apoptosis. CSCs were cultured in DOX-conditioned cell culture medium and displayed reduced live cell numbers as well as high levels of apoptosis. Encapsulation of CSCs in alginate alone failed to prevent apoptosis. Encapsulation in SOD-loaded alginate reduced apoptosis to near-normal levels, whilst metabolic activity was returned to baseline. In conclusion, this study demonstrates that encapsulation of CSCs in SOD-loaded alginate hydrogel enhances CSC survival in the presence of DOX, raising the possibility of its application as a novel therapy for the treatment of acute and early onset DOX-induced cardiotoxicity.

  20. Osteogenic Differentiation of Human Amniotic Epithelial Cells and Its Application in Alveolar Defect Restoration

    PubMed Central

    Jiawen, Si; Jianjun, Zhang; Jiewen, Dai; Dedong, Yu; Hongbo, Yu; Jun, Shi; Xudong, Wang; Shen, Steve G.F.

    2014-01-01

    The present study investigated the detailed in vitro osteogenic differentiation process and in vivo bone regenerative property of human amniotic epithelial cells (hAECs). The in vitro osteogenic differentiation process of hAECs was evaluated by biochemical staining, real-time polymerase chain reaction, and immunofluorescence. Next, β-tricalcium phosphate (β-TCP) scaffolds alone or loaded with hAECs were implanted into the alveolar defects of rats. Micro-computed tomography evaluation and histologic studies were conducted. Our results validated the in vitro osteogenic capacity of hAECs by upregulation of Runx2, osterix, alkaline phosphatase, collagen I, and osteopontin, with positive biochemical staining for osteoblasts. An epithelial-mesenchymal transformation process might be involved in the osteogenic differentiation of hAECs by increased expression of transforming growth factor-β1. Our data also demonstrated that in vivo implantation of hAECs loaded on β-TCP scaffolds, not only improved bone regeneration by direct participation, but also reduced the early host immune response to the scaffolds. The presented data indicate that hAECs possess proper osteogenic differentiation potential and a modulatory influence on the early tissue remodeling process, making these cells a potential source of progenitor cells for clinical restoration of the alveolar defect. PMID:25368378

  1. Paracrine mechanisms of stem cell reparative and regenerative actions in the heart

    PubMed Central

    Mirotsou, Maria; Jayawardena, Tilanthi M; Schmeckpeper, Jeffrey; Gnecchi, Massimiliano; Dzau, Victor J

    2010-01-01

    Stem cells play an important role in restoring cardiac function in the damaged heart. In order to mediate repair, stem cells need to replace injured tissue by differentiating into specialized cardiac cell lineages and/or manipulating the cell and molecular mechanisms governing repair. Despite early reports describing engraftment and successful regeneration of cardiac tissue in animal models of heart failure, these events appear to be infrequent and yield too few new cardiomyocytes to account for the degree of improved cardiac function observed. Instead, mounting evidence suggests that stem cell mediated repair takes place via the release of paracrine factors into the surrounding tissue that subsequently direct a number of restorative processes including myocardial protection, neovascularization, cardiac remodeling, and differentiation. The potential for diverse stem cell populations to moderate many of the same processes as well as key paracrine factors and molecular pathways involved in stem cell-mediated cardiac repair will be discussed in this review. PMID:20727900

  2. Differentiation of cardiosphere-derived cells into a mature cardiac lineage using biodegradable poly(N-isopropylacrylamide) hydrogels.

    PubMed

    Li, Zhenqing; Guo, Xiaolei; Matsushita, Satoshi; Guan, Jianjun

    2011-04-01

    A family of injectable and thermosensitive hydrogels suitable for myocardial injection was developed to deliver cardiosphere-derived cells (CDCs), an emerging and promising cell type for cardiac cell therapy. The hydrogels were based on polycaprolactone, N-isopropylacrylamide, 2-hydroxyethyl methacrylate and dimethyl-γ-butyrolactone acrylate. Atom transfer radical polymerization was used to synthesize hydrogels with a well-defined structure and well-controlled properties. The hydrogel solutions possessed thermal transition temperatures around room temperature and exhibited injectability suitable for myocardial injection. At 37 °C, the hydrogel solutions were capable of forming solid gels within 5s. This would allow the hydrogels to largely retain in the heart during injection. The hydrogels were highly flexible at body temperature with moduli matching those of the rat and human myocardium, and breaking strains higher than those of the myocardium, enabling them to respond synchronically with heart motion. The well-controlled polymer structure allowed for precisely controlling and decoupling water content and stiffness that affect cell differentiation. DNA assay demonstrated that CDCs proliferated in the 3D hydrogels during a 2-week culture period. CDCs maintained their colony formation capability in the hydrogel. Interestingly, hydrogels directed CDCs differentiation into mature cardiac lineage. At mRNA level, the mature cardiac specific transcript factors cardiac troponin T (cTnT) and cardiac myosin heavy chain (MYH6) were up-regulated, while the pre-mature cardiac marker GATA4 was down-regulated even after 1 day of encapsulation. CDC differentiation was interplayed by hydrogel stiffness and collagen in the hydrogel. Hydrogel with modulus ∼31 kPa was found to more significantly up-regulate cardiac expression than that with modulus ∼5 or ∼63 kPa. cTnT expression was largely regulated by both stiffness and collagen while MYH6 was mainly regulated by

  3. An essential cell-autonomous role for hepcidin in cardiac iron homeostasis

    PubMed Central

    Lakhal-Littleton, Samira; Wolna, Magda; Chung, Yu Jin; Christian, Helen C; Heather, Lisa C; Brescia, Marcella; Ball, Vicky; Diaz, Rebeca; Santos, Ana; Biggs, Daniel; Clarke, Kieran; Davies, Benjamin; Robbins, Peter A

    2016-01-01

    Hepcidin is the master regulator of systemic iron homeostasis. Derived primarily from the liver, it inhibits the iron exporter ferroportin in the gut and spleen, the sites of iron absorption and recycling respectively. Recently, we demonstrated that ferroportin is also found in cardiomyocytes, and that its cardiac-specific deletion leads to fatal cardiac iron overload. Hepcidin is also expressed in cardiomyocytes, where its function remains unknown. To define the function of cardiomyocyte hepcidin, we generated mice with cardiomyocyte-specific deletion of hepcidin, or knock-in of hepcidin-resistant ferroportin. We find that while both models maintain normal systemic iron homeostasis, they nonetheless develop fatal contractile and metabolic dysfunction as a consequence of cardiomyocyte iron deficiency. These findings are the first demonstration of a cell-autonomous role for hepcidin in iron homeostasis. They raise the possibility that such function may also be important in other tissues that express both hepcidin and ferroportin, such as the kidney and the brain. DOI: http://dx.doi.org/10.7554/eLife.19804.001 PMID:27897970

  4. Induced Pluripotent Stem Cell-derived Cardiomyocytes: Cardiac Applications, Opportunities and Challenges.

    PubMed

    Moreau, Adrien; Boutjdir, Mohamed; Chahine, Mohamed

    2017-03-28

    Chronic diseases are the primary cause of mortality worldwide, accounting for 67% of deaths. One of the major challenges in developing new treatments is the lack of understanding of the exact underlying biological and molecular mechanisms. Chronic cardiovascular diseases are the single most common cause of death worldwide, and sudden deaths due to cardiac arrhythmias account for approximately 50% of all such cases. Traditional genetic screening for genes involved in cardiac disorders is laborious and frequently fails to detect the mutation that explains or causes the disorder. However, when mutations are identified, human induced pluripotent stem cells (hiPSCs) derived from affected patients make it possible to address fundamental research questions directly relevant to human health. As such, hiPSC technology has recently been used to model human diseases and patient-specific hiPSC-derived cardiomyocytes (hiPSC-CMs) thus offer