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1. Physiological and pharmacological stimulation for in vitro maturation of substrate metabolism in human induced pluripotent stem cell-derived cardiomyocytes

Author

Colleen A. Lopez, Heba Hussain A. A. Al-Siddiqi, Ujang Purnama, Sonia Iftekhar, Arne A. N. Bruyneel, Matthew Kerr, Rabia Nazir, Maria da Luz Sousa Fialho, Sophia Malandraki-Miller, Rita Alonaizan, Fatemeh Kermani, Lisa C. Heather, Jan Czernuszka, and Carolyn A. Carr

Subjects
Medicine, Science
Abstract

Abstract Human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) enable human cardiac cells to be studied in vitro, although they use glucose as their primary metabolic substrate and do not recapitulate the properties of adult cardiomyocytes. Here, we have explored the interplay between maturation by stimulation of fatty acid oxidation and by culture in 3D. We have investigated substrate metabolism in hiPSC-CMs grown as a monolayer and in 3D, in porous collagen-derived scaffolds and in engineered heart tissue (EHT), by measuring rates of glycolysis and glucose and fatty acid oxidation (FAO), and changes in gene expression and mitochondrial oxygen consumption. FAO was stimulated by activation of peroxisome proliferator-activated receptor alpha (PPARα), using oleate and the agonist WY-14643, which induced an increase in FAO in monolayer hiPSC-CMs. hiPSC-CMs grown in 3D on collagen-derived scaffolds showed reduced glycolysis and increased FAO compared with monolayer cells. Activation of PPARα further increased FAO in cells on collagen/elastin scaffolds but not collagen or collagen/chondroitin-4-sulphate scaffolds. In EHT, FAO was significantly higher than in monolayer cells or those on static scaffolds and could be further increased by culture with oleate and WY-14643. In conclusion, a more mature metabolic phenotype can be induced by culture in 3D and FAO can be incremented by pharmacological stimulation.

Published
2021
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2. Metabolic flux analyses to assess the differentiation of adult cardiac progenitors after fatty acid supplementation

Author

Sophia Malandraki-Miller, Colleen A. Lopez, Rita Alonaizan, Ujang Purnama, Filippo Perbellini, Kathy Pakzad, and Carolyn A. Carr

Subjects
Biology (General), QH301-705.5
Abstract

Myocardial infarction is the most prevalent of cardiovascular diseases and pharmacological interventions do not lead to restoration of the lost cardiomyocytes. Despite extensive stem cell therapy studies, clinical trials using cardiac progenitor cells have shown moderate results. Furthermore, differentiation of endogenous progenitors to mature cardiomyocytes is rarely reported.A metabolic switch from glucose to fatty acid oxidation occurs during cardiac development and cardiomyocyte maturation, however in vitro differentiation protocols do not consider the lack of fatty acids in cell culture media. The aim of this study was to assess the effect of this metabolic switch on control and differentiated adult cardiac progenitors, by fatty acid supplementation.Addition of oleic acid stimulated the peroxisome proliferator-activated receptor alpha pathway and led to maturation of the cardiac progenitors, both before and after transforming growth factor-beta 1 differentiation. Addition of oleic acid following differentiation increased expression of myosin heavy chain 7 and connexin 43. Also, total glycolytic metabolism increased, as did mitochondrial membrane potential and glucose and fatty acid transporter expression.This work provides new insights into the importance of fatty acids, and of peroxisome proliferator-activated receptor alpha, in cardiac progenitor differentiation. Harnessing the oxidative metabolic switch induced maturation of differentiated endogenous stem cells.(200 words) Keywords: Cardiac stem cells, Differentiation, Metabolism, Oleic acid OA, Fatty acid oxidation, PPARα

Published
2019
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3. Changing Metabolism in Differentiating Cardiac Progenitor Cells—Can Stem Cells Become Metabolically Flexible Cardiomyocytes?

Author

Sophia Malandraki-Miller, Colleen A. Lopez, Heba Al-Siddiqi, and Carolyn A. Carr

Subjects
heart, progenitor cells, substrate metabolism, mitochondria, differentiation, cardiomyocytes, Diseases of the circulatory (Cardiovascular) system, RC666-701
Abstract

The heart is a metabolic omnivore and the adult heart selects the substrate best suited for each circumstance, with fatty acid oxidation preferred in order to fulfill the high energy demand of the contracting myocardium. The fetal heart exists in an hypoxic environment and obtains the bulk of its energy via glycolysis. After birth, the “fetal switch” to oxidative metabolism of glucose and fatty acids has been linked to the loss of the regenerative phenotype. Various stem cell types have been used in differentiation studies, but most are cultured in high glucose media. This does not change in the majority of cardiac differentiation protocols. Despite the fact that metabolic state affects marker expression and cellular function and activity, the substrate composition is currently being overlooked. In this review we discuss changes in cardiac metabolism during development, the various protocols used to differentiate progenitor cells to cardiomyocytes, what is known about stem cell metabolism and how consideration of metabolism can contribute toward maturation of stem cell-derived cardiomyocytes.

Published
2018
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4. Epigallocatechin gallate facilitates extracellular elastin fiber formation in induced pluripotent stem cell derived vascular smooth muscle cells for tissue engineering

Author

Matthew W. Ellis, Muhammad Riaz, Yan Huang, Christopher W. Anderson, Jiesi Luo, Jinkyu Park, Colleen A. Lopez, Luke D. Batty, Kimberley H. Gibson, and Yibing Qyang

Subjects
Tissue Engineering, Induced Pluripotent Stem Cells, Myocytes, Smooth Muscle, Humans, Reproducibility of Results, Cardiology and Cardiovascular Medicine, Molecular Biology, Article, Catechin, Muscle, Smooth, Vascular, Elastin
Abstract

Tissue engineered vascular grafts possess several advantages over synthetic or autologous grafts, including increased availability and reduced rates of infection and thrombosis. Engineered grafts constructed from human induced pluripotent stem cell derivatives further offer enhanced reproducibility in graft production. One notable obstacle to clinical application of these grafts is the lack of elastin in the vessel wall, which would serve to endow compliance in addition to mechanical strength. This study establishes the ability of the polyphenol compound epigallocatechin gallate, a principal component of green tea, to facilitate the extracellular formation of elastin fibers in vascular smooth muscle cells derived from human induced pluripotent stem cells. Further, this study describes the creation of a doxycycline-inducible elastin expression system to uncouple elastin production from vascular smooth muscle cell proliferative capacity to permit fiber formation in conditions conducive to robust tissue engineering.

Published
2022
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5. Modular design of a tissue engineered pulsatile conduit using human induced pluripotent stem cell-derived cardiomyocytes

Author

Muhammad Riaz, Mehmet H. Kural, Christopher W. Anderson, Yibing Qyang, Yan Huang, Jiesi Luo, Jin-Kyu Park, Subhash K. Das, Colleen A. Lopez, Liqiong Gui, Ronald Ng, Laura E. Niklason, Juan Wang, Stuart G. Campbell, and Lorenzo R. Sewanan

Subjects
Swine, medicine.medical_treatment, Induced Pluripotent Stem Cells, 0206 medical engineering, Biomedical Engineering, Pulsatile flow, 02 engineering and technology, Proof of Concept Study, Biochemistry, Collagen Type I, Umbilical Arteries, Article, Biomaterials, Fontan procedure, Electrical conduit, Tissue engineering, medicine, Animals, Humans, Myocytes, Cardiac, Induced pluripotent stem cell, Molecular Biology, Decellularization, Tissue Engineering, Tissue Scaffolds, business.industry, Myocardium, Cell Differentiation, General Medicine, Fibroblasts, 021001 nanoscience & nanotechnology, medicine.disease, 020601 biomedical engineering, Extracellular Matrix, medicine.anatomical_structure, Ventricle, Heart failure, Female, 0210 nano-technology, business, Polyglycolic Acid, Biotechnology, Biomedical engineering
Abstract

Single ventricle heart defects (SVDs) are congenital disorders that result in a variety of complications, including increased ventricular mechanical strain and mixing of oxygenated and deoxygenated blood, leading to heart failure without surgical intervention. Corrective surgery for SVDs are traditionally handled by the Fontan procedure, requiring a vascular conduit for completion. Although effective, current conduits are limited by their inability to aid in pumping blood into the pulmonary circulation. In this report, we propose an innovative and versatile design strategy for a tissue engineered pulsatile conduit (TEPC) to aid circulation through the pulmonary system by producing contractile force. Several design strategies were tested for production of a functional TEPC. Ultimately, we found that porcine extracellular matrix (ECM)-based engineered heart tissue (EHT) composed of human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) and primary cardiac fibroblasts (HCF) wrapped around decellularized human umbilical artery (HUA) made an efficacious basal TEPC. Importantly, the TEPCs showed effective electrical and mechanical function. Initial pressure readings from our TEPC in vitro (0.68 mmHg) displayed efficient electrical conductivity enabling them to follow electrical pacing up to a 2 Hz frequency. This work represents a proof of principle study for our current TEPC design strategy. Refinement and optimization of this promising TEPC design will lay the groundwork for testing the construct's therapeutic potential in the future. Together this work represents a progressive step toward developing an improved treatment for SVD patients. Statement of significance Single Ventricle Cardiac defects (SVD) are a form of congenital disorder with a morbid prognosis without surgical intervention. These patients are treated through the Fontan procedure which requires vascular conduits to complete. Fontan conduits have been traditionally made from stable or biodegradable materials with no pumping activity. Here, we propose a tissue engineered pulsatile conduit (TEPC) for use in Fontan circulation to alleviate excess strain in SVD patients. In contrast to previous strategies for making a pulsatile Fontan conduit, we employ a modular design strategy that allows for the optimization of each component individually to make a standalone tissue. This work sets the foundation for an in vitro, trainable human induced pluripotent stem cell based TEPC.

Published
2020
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6. Strengthening STEM Education through Community Partnerships

Author

Colleen A, Lopez, Jon, Rocha, Matthew, Chapman, Kathleen, Rocha, Stephanie, Wallace, Steven, Baum, Brian R, Lawler, and Bianca R, Mothé

Subjects
ComputingMilieux_COMPUTERSANDEDUCATION, Article
Abstract

California State University San Marcos (CSUSM) and San Marcos Elementary Schools have established a partnership to offer a large-scale community service learning opportunity to enrich science curriculum for K-5 students. It provides an opportunity for science, technology, engineering, and math (STEM) majors to give back to the community, allowing them to experience teaching in an elementary classroom setting, in schools that lack the resources and science instructor specialization needed to instill consistent science curricula. CSUSM responded to this need for more STEM education by mobilizing its large STEM student body to design hands-on, interactive science lessons based on Next Generation Science Standards (NGSS). Since 2012, the program has reached out to over four thousand K-5 students, and assessment data have indicated an increase in STEM academic performance and interest.

Published
2017

7. Tissue-Engineered Vascular Grafts with Advanced Mechanical Strength from Human iPSCs

Author

Mehmet H. Kural, Yibing Qyang, Muhammad Riaz, Guangxin Li, Liqiong Gui, Jiesi Luo, Laura E. Niklason, Stuart G. Campbell, Liping Zhao, Colleen A. Lopez, Alan Dardik, Lingfeng Qin, Yifan Yuan, Shang Min Zhang, George Tellides, J. Alexander Clark, Xiaoqiang Cong, Juan Wang, Shun Ono, Matthew W. Ellis, Yan Huang, and Akitsu Hotta

Subjects
0303 health sciences, Tissue engineered, Vascular smooth muscle, Pulsatile flow, Cell Biology, Biology, 03 medical and health sciences, 0302 clinical medicine, Biodegradable scaffold, Mechanical strength, Genetics, Molecular Medicine, Report generation, Human Induced Pluripotent Stem Cells, Induced pluripotent stem cell, 030217 neurology & neurosurgery, 030304 developmental biology, Biomedical engineering
Abstract

Summary Vascular smooth muscle cells (VSMCs) can be derived in large numbers from human induced pluripotent stem cells (hiPSCs) for producing tissue-engineered vascular grafts (TEVGs). However, hiPSC-derived TEVGs are hampered by low mechanical strength and significant radial dilation after implantation. Here, we report generation of hiPSC-derived TEVGs with mechanical strength comparable to native vessels used in arterial bypass grafts by utilizing biodegradable scaffolds, incremental pulsatile stretching, and optimal culture conditions. Following implantation into a rat aortic model, hiPSC-derived TEVGs show excellent patency without luminal dilation and effectively maintain mechanical and contractile function. This study provides a foundation for future production of non-immunogenic, cellularized hiPSC-derived TEVGs composed of allogenic vascular cells, potentially serving needs to a considerable number of patients whose dysfunctional vascular cells preclude TEVG generation via other methods.

Published
2020
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8. Stem Cell Biology

Author

Evan Y. Snyder, Stephen Yip, Colleen A. Lopez, Yang Liu, Cameron D Pernia, and Eniko Sajti

Subjects
Biology, Stem cell biology, Cell biology
Published
2017
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9. Contributors

Author

Soraya Abbasi, James Abbey, N. Scott Adzick, Sun-Young Ahn, Kurt H. Albertine, Karel Allegaert, Seth L. Alper, Gabriel Altit, Steven M. Altschuler, Ruben E. Alvaro, Jennifer M.H. Amorosa, Kelsey L. Anbuhl, Claus Yding Andersen, Richard A. Anderson, David J. Askenazi, Richard Lambert Auten, Julie Autmizguine, Timur Azhibekov, Stephen A. Back, Jérôme Badaut, Peter Russell Baker, Philip L. Ballard, Eduardo H. Bancalari, Tatiana Barichello, Frederick Battaglia, Michel Baum, Simon Beggs, Edward F. Bell, Corinne Benchimol, Manon J.N.L. Benders, Laura Bennet, Phillip R. Bennett, Melvin Berger, Wolfgang Bernhard, John F. Bertram, Vikrant K. Bhosle, Vinod K. Bhutani, M. Jane Black, Joseph M. Bliss, David L. Bolender, Joline E. Brandenburg, Delma L. Broussard, Laura Davidson Brown, Douglas G. Burrin, Barbara Cannon, Michael Caplan, Susan E. Carlson, David P. Carlton, Georgina Caruana, William J. Cashore, Piya Chaemsaithong, Noppadol Chaiyasit, Jennifer R. Charlton, Carol L. Cheatham, Sylvain Chemtob, Yi-Yung Chen, Robert L. Chevalier, Sadhana Chheda, Andrew J. Childs, Robert D. Christensen, Alison Chu, David H. Chu, Maria Roberta Cilio, David A. Clark, Jane Cleary-Goldman, Ethel G. Clemente, John A. Clements, Ronald I. Clyman, Susan S. Cohen, John Colombo, Richard M. Cowett, Peter A. Crawford, James E. Crowe, Luise A. Cullen-McEwen, Wayne S. Cutfield, Mary E. D'Alton, Enrico Danzer, Christophe Delacourt, Sherin U. Devaskar, Thomas G. Diacovo, Nikolina Docheva, John P. Dormans, Kevin Dysart, Afif El-Khuffash, Peter James Ellis, Kerry McGarr Empey, Baris Ercal, Melinda Erdős, Robert P. Erickson, Mohamed A. Fahim, Arij Faksh, Hans-Georg Frank, Philippe S. Friedlich, Jed Friedman, Yuansheng Gao, Marianne Garland, Donna Geddes, Michael K. Georgieff, Jason Gien, Dino A. Giussani, Armond S. Goldman, Efrén González, Misty Good, Denis M. Grant, Lucy R. Green, Emmanouil Grigoriou, Adda Grimberg, Ian Gross, Ruth E. Grunau, Jean-Pierre Guignard, Alistair Jan Gunn, Nursen Gurtunca, Alice Hadchouel, Gabriel G. Haddad, Henrik Hagberg, Thomas Hale, K. Michael Hambidge, Cathy Hammerman, Thor Willy Ruud Hansen, Mark A. Hanson, Richard Harding, Mary Catherine Harris, Peter Hartmann, Foteini Hassiotou, Guttorm Haugen, Colin P. Hawkes, William W. Hay, Christina E. Hayward, Vivi M. Heine, Ann Hellström, Michael A. Helmrath, Karen D. Hendricks-Muñoz, Emilio Herrera, Michael J. Hiatt, Steven B. Hoath, Stuart B. Hooper, Stephen A. Huang, Silvia Iacobellli, Terrie E. Inder, M. Luisa Iruela-Arispe, Sudarshan R. Jadcherla, Deepak Jain, Thomas Jansson, John Lynn Jefferies, Jennifer G. Jetton, Alan H. Jobe, Lois H. Johnson, Richard B. Johnston, Rebecca Lee Jones, Pedro A. Jose, Satish C. Kalhan, Suhas G. Kallapur, Michael Kaplan, Stanley Kaplan, Heidi Eigenrauch Karpen, Saul J. Karpen, S. Ananth Karumanchi, Frederick J. Kaskel, Anup C. Katheria, Lorraine E. Levitt Katz, Susan E. Keeney, Steven E. Kern, Shirin Khanjani, Laurie E. Kilpatrick, Chang-Ryul Kim, John P. Kinsella, Torvid Kiserud, Joyce M. Koenig, Tobias R. Kollmann, Jay K. Kolls, Nancy F. Krebs, Thomas J. Kulik, Jessica Katz Kutikov, Satyan Lakshminrusimha, Angelo A. Lamola, Miguel Angel Lasunción, Pascal M. Lavoie, Tucker W. LeBien, Mary M. Lee, Matthew K. Lee, Yvonne K. Lee, Sandra Leibel, Fred Levine, Ofer Levy, Yang Liu, Steven Lobritto, Cynthia A. Loomis, Colleen A. Lopez, David A. MacIntyre, Maxime M. Mahe, Akhil Maheshwari, Anastasiya Mankouski, Carlos B. Mantilla, Arnaud Marchant, Kara Gross Margolis, M. Michele Mariscalco, László Maródi, Karel Maršál, Richard J. Martin, Douglas G. Matsell, Dwight E. Matthews, Harry J. McArdle, James L. McManaman, Patrick J. McNamara, Patrick S. McQuillen, Tim C. McQuinn, Judith S. Mercer, Giacomo Meschia, Steven P. Miller, Parviz Minoo, Paul Monagle, Jacopo P. Mortola, Louis J. Muglia, Upender K. Munshi, Ran Namgung, Sumana Narasimhan, Jan Nedergaard, Josef Neu, Sanjay K. Nigam, Lawrence M. Nogee, Shahab Noori, Barbara M. O'Brien, Robin K. Ohls, Henar Ortega-Senovilla, Justin M. O'Sullivan, Sarah A. Owusu, Abhijeet Pal, Howard B. Panitch, Anna A. Penn, Raymond B. Penn, Cameron Pernia, Anthony F. Philipps, Joseph A. Picoraro, Francesco Pisani, David Pleasure, Jeanette R. Pleasure, Samuel J. Pleasure, Scott L. Pomeroy, Martin Post, Y.S. Prakash, Joshua D. Prozialeck, Theodore J. Pysher, Raymond Quigley, Marlene Rabinovitch, Thomas M. Raffay, J. Usha Raj, Haley Ramsey, Sarosh Rana, Tara Marie Randis, Manon Ranger, Adam J. Ratner, Timothy R.H. Regnault, Henrique Rigatto, Natalie E. Rintoul, Roberto Romero, James C. Rose, Charles R. Rosenfeld, A. Catharine Ross, Henry J. Rozycki, Thomas D. Ryan, Rakesh Sahni, Eniko Sajti, Harvey B. Sarnat, Lisa M. Satlin, Ola Didrik Saugstad, William Schierding, Frank C. Schmalstieg, George J. Schwartz, Jeffrey Schwartz, Jeffrey L. Segar, David T. Selewski, Istvan Seri, Thomas H. Shaffer, Kara N. Shah, Martin J. Shearer, Sharareh Shojaie, Noah F. Shroyer, Colin P. Sibley, Gary C. Sieck, Rebecca A. Simmons, Emidio M. Sivieri, Francine G. Smith, Lois E.H. Smith, Ian M. Smyth, Brian S. Snarr, Evan Y. Snyder, Martha Sola-Visner, Michael J. Solhaug, Mark A. Sperling, Lakshmi Srinivasan, Andreas Stahl, Charles A. Stanley, Robin H. Steinhorn, Barbara S. Stonestreet, Janette F. Strasburger, Dennis M. Styne, Lori Sussel, Emily W.Y. Tam, Libo Tan, Claire Thornton, Daniel J. Tollin, Beáta Tóth, Jeffrey A. Towbin, Ashley Trocle, William E. Truog, Reginald C. Tsang, Kristin M. Uhler, John N. Van Den Anker, Johannes (Hans) B. van Goudoever, Susan J. Vannucci, Mark H. Vickers, Daniela Virgintino, Joseph J. Volpe, Neeta L. Vora, Neha V. Vyas, Annette Wacker-Gussmann, Megan J. Wallace, Brian H. Walsh, Alice M. Wang, David Warburton, Robert M. Ward, Kristi L. Watterberg, Lynne A. Werner, Barry K. Wershil, Susan E. Wert, Andy Wessels, Jeffrey A. Whitsett, Michael Wise, Matthias T. Wolf, Marla R. Wolfson, Hector R. Wong, James L. Wynn, Lami Yeo, Stephen Yip, Bradley A Yoder, Mervin C. Yoder, Momoko Yoshimoto, Christopher J. Yuskaitis, Dan Zhou, and Ann Zovein

Published
2017
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10. Attitudes of nonsecluded patients toward seclusion rooms

Author

Christine Murray, Lee S. Mann, Colleen L. Lopez, and Thomas N. Wise

Subjects
Adult, Male, medicine.medical_specialty, business.industry, media_common.quotation_subject, Mental Disorders, Psychiatric Department, Hospital, Social Environment, Seclusion room, Patient Isolation, Psychiatry and Mental health, Feeling, Attitude, Medicine, Humans, Female, business, Psychiatry, Seclusion, media_common
Abstract

This study investigated the attitudes toward seclusion rooms of a group of hospitalized psychiatric patients who were not at the time secluded. Those patients who had never been secluded endorsed more negative feelings about seclusion room use than did those who had actually been secluded during prior hospitalizations. Women were more critical of the seclusion process than were men.

Published
1988

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