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Mucci S, Isaja L, Rodríguez-Varela MS, Ferriol-Laffouillere SL, Marazita M, Videla-Richardson GA, Sevlever GE, Scassa ME, Romorini L. Acute severe hypoxia induces apoptosis of human pluripotent stem cells by a HIF-1α and P53 independent mechanism. Sci Rep 2022; 12:18803. [PMID: 36335243 PMCID: PMC9637190 DOI: 10.1038/s41598-022-23650-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Accepted: 11/03/2022] [Indexed: 11/06/2022] Open
Abstract
Human embryonic and induced pluripotent stem cells are self-renewing pluripotent stem cells (hPSCs) that can differentiate into a wide range of specialized cells. Although moderate hypoxia (5% O2) improves hPSC self-renewal, pluripotency, and cell survival, the effect of acute severe hypoxia (1% O2) on hPSC viability is still not fully elucidated. In this sense, we explore the consequences of acute hypoxia on hPSC survival by culturing them under acute (maximum of 24 h) physical severe hypoxia (1% O2). After 24 h of hypoxia, we observed HIF-1α stabilization concomitant with a decrease in cell viability. We also observed an increase in the apoptotic rate (western blot analysis revealed activation of CASPASE-9, CASPASE-3, and PARP cleavage after hypoxia induction). Besides, siRNA-mediated downregulation of HIF-1α and P53 did not significantly alter hPSC apoptosis induced by hypoxia. Finally, the analysis of BCL-2 family protein expression levels disclosed a shift in the balance between pro- and anti-apoptotic proteins (evidenced by an increase in BAX/MCL-1 ratio) caused by hypoxia. We demonstrated that acute physical hypoxia reduced hPSC survival and triggered apoptosis by a HIF-1α and P53 independent mechanism.
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Affiliation(s)
- Sofía Mucci
- grid.418954.50000 0004 0620 9892Laboratorios de Investigación Aplicada en Neurociencias (LIAN-CONICET), Fundación Para La Lucha Contra Las Enfermedades Neurológicas de La Infancia (Fleni), Ruta 9, Km 52.5, B1625XAF Belén de Escobar, Provincia de Buenos Aires Argentina
| | - Luciana Isaja
- grid.418954.50000 0004 0620 9892Laboratorios de Investigación Aplicada en Neurociencias (LIAN-CONICET), Fundación Para La Lucha Contra Las Enfermedades Neurológicas de La Infancia (Fleni), Ruta 9, Km 52.5, B1625XAF Belén de Escobar, Provincia de Buenos Aires Argentina
| | - María Soledad Rodríguez-Varela
- grid.418954.50000 0004 0620 9892Laboratorios de Investigación Aplicada en Neurociencias (LIAN-CONICET), Fundación Para La Lucha Contra Las Enfermedades Neurológicas de La Infancia (Fleni), Ruta 9, Km 52.5, B1625XAF Belén de Escobar, Provincia de Buenos Aires Argentina
| | - Sofía Luján Ferriol-Laffouillere
- grid.418954.50000 0004 0620 9892Laboratorios de Investigación Aplicada en Neurociencias (LIAN-CONICET), Fundación Para La Lucha Contra Las Enfermedades Neurológicas de La Infancia (Fleni), Ruta 9, Km 52.5, B1625XAF Belén de Escobar, Provincia de Buenos Aires Argentina
| | - Mariela Marazita
- grid.418954.50000 0004 0620 9892Laboratorios de Investigación Aplicada en Neurociencias (LIAN-CONICET), Fundación Para La Lucha Contra Las Enfermedades Neurológicas de La Infancia (Fleni), Ruta 9, Km 52.5, B1625XAF Belén de Escobar, Provincia de Buenos Aires Argentina
| | - Guillermo Agustín Videla-Richardson
- grid.418954.50000 0004 0620 9892Laboratorios de Investigación Aplicada en Neurociencias (LIAN-CONICET), Fundación Para La Lucha Contra Las Enfermedades Neurológicas de La Infancia (Fleni), Ruta 9, Km 52.5, B1625XAF Belén de Escobar, Provincia de Buenos Aires Argentina
| | - Gustavo Emilio Sevlever
- grid.418954.50000 0004 0620 9892Laboratorios de Investigación Aplicada en Neurociencias (LIAN-CONICET), Fundación Para La Lucha Contra Las Enfermedades Neurológicas de La Infancia (Fleni), Ruta 9, Km 52.5, B1625XAF Belén de Escobar, Provincia de Buenos Aires Argentina
| | - María Elida Scassa
- grid.418954.50000 0004 0620 9892Laboratorios de Investigación Aplicada en Neurociencias (LIAN-CONICET), Fundación Para La Lucha Contra Las Enfermedades Neurológicas de La Infancia (Fleni), Ruta 9, Km 52.5, B1625XAF Belén de Escobar, Provincia de Buenos Aires Argentina
| | - Leonardo Romorini
- grid.418954.50000 0004 0620 9892Laboratorios de Investigación Aplicada en Neurociencias (LIAN-CONICET), Fundación Para La Lucha Contra Las Enfermedades Neurológicas de La Infancia (Fleni), Ruta 9, Km 52.5, B1625XAF Belén de Escobar, Provincia de Buenos Aires Argentina
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Basundra R, Kapoor S, Hollville E, Kiapour N, Beltran Lopez A, Marie Melchiorre N, Deshmukh M. Constitutive High Expression of NOXA Sensitizes Human Embryonic Stem Cells for Rapid Cell Death. Stem Cells 2022; 40:49-58. [PMID: 35511861 PMCID: PMC9199843 DOI: 10.1093/stmcls/sxab008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Accepted: 09/02/2021] [Indexed: 01/21/2023]
Abstract
Human embryonic stem (hES) cells are highly sensitive to apoptotic stimuli such as DNA damage, which allows for the rapid elimination of mutated cells during development. However, the mechanisms that maintain hES cells in the primed apoptotic state are not completely known. Key activators of apoptosis, the BH3-only proteins, are present at low levels in most cell types. In contrast, hES cells have constitutive high levels of the BH3-only protein, NOXA. We examined the importance of NOXA for enabling apoptosis in hES cells. hES cells deleted for NOXA showed remarkable protection against multiple apoptotic stimuli. NOXA was constitutively localized to the mitochondria, where it interacted with MCL1. Strikingly, inhibition of MCL1 in NOXA knockout cells was sufficient to sensitize these cells to DNA damage-induced cell death. Our study demonstrates that an essential function of constitutive high levels of NOXA in hES cells is to effectively antagonize MCL1 to permit rapid apoptosis.
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Affiliation(s)
- Richa Basundra
- Neuroscience Center, University of North Carolina, Chapel Hill, NC, USA
| | - Sahil Kapoor
- Neuroscience Center, University of North Carolina, Chapel Hill, NC, USA
| | - Emilie Hollville
- Neuroscience Center, University of North Carolina, Chapel Hill, NC, USA
| | - Nazanin Kiapour
- Neuroscience Center, University of North Carolina, Chapel Hill, NC, USA
| | - Adriana Beltran Lopez
- Human Pluripotent Stem Cell Core, Department of Pharmacology, University of North Carolina, Chapel Hill, NC, USA
| | | | - Mohanish Deshmukh
- Neuroscience Center, University of North Carolina, Chapel Hill, NC, USA
- Department of Cell Biology and Physiology, University of North Carolina, Chapel Hill, NC, USA
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Affiliation(s)
- Seungbok Yang
- Department of Life Sciences, Pohang University of Science and Technology (POSTECH), Pohang 37673, Korea
| | - Yoonjae Cho
- Department of Life Sciences, Pohang University of Science and Technology (POSTECH), Pohang 37673, Korea
| | - Jiwon Jang
- Department of Life Sciences, Pohang University of Science and Technology (POSTECH), Pohang 37673, Korea
- Institute of Convergence Science, Yonsei University, Seoul 03722, Korea
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4
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Abstract
Metabolism is an important part of tumorigenesis as well as progression. The various cancer metabolism pathways, such as glucose metabolism and glutamine metabolism, directly regulate the development and progression of cancer. The pathways by which the cancer cells rewire their metabolism according to their needs, surrounding environment and host tissue conditions are an important area of study. The regulation of these metabolic pathways is determined by various oncogenes, tumor suppressor genes, as well as various constituent cells of the tumor microenvironment. Expanded studies on metabolism will help identify efficient biomarkers for diagnosis and strategies for therapeutic interventions and countering ways by which cancers may acquire resistance to therapy.
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Hu XM, Zhang Q, Zhou RX, Wu YL, Li ZX, Zhang DY, Yang YC, Yang RH, Hu YJ, Xiong K. Programmed cell death in stem cell-based therapy: Mechanisms and clinical applications. World J Stem Cells 2021; 13:386-415. [PMID: 34136072 PMCID: PMC8176847 DOI: 10.4252/wjsc.v13.i5.386] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Revised: 04/26/2021] [Accepted: 05/07/2021] [Indexed: 02/06/2023] Open
Abstract
Stem cell-based therapy raises hopes for a better approach to promoting tissue repair and functional recovery. However, transplanted stem cells show a high death percentage, creating challenges to successful transplantation and prognosis. Thus, it is necessary to investigate the mechanisms underlying stem cell death, such as apoptotic cascade activation, excessive autophagy, inflammatory response, reactive oxygen species, excitotoxicity, and ischemia/hypoxia. Targeting the molecular pathways involved may be an efficient strategy to enhance stem cell viability and maximize transplantation success. Notably, a more complex network of cell death receives more attention than one crucial pathway in determining stem cell fate, highlighting the challenges in exploring mechanisms and therapeutic targets. In this review, we focus on programmed cell death in transplanted stem cells. We also discuss some promising strategies and challenges in promoting survival for further study.
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Affiliation(s)
- Xi-Min Hu
- Department of Anatomy and Neurobiology, School of Basic Medical Sciences, Central South University, Changsha 410013, Hunan Province, China
- Department of Dermatology, Xiangya Hospital, Central South University, Changsha 410013, Hunan Province, China
| | - Qi Zhang
- Department of Anatomy and Neurobiology, School of Basic Medical Sciences, Central South University, Changsha 410013, Hunan Province, China
| | - Rui-Xin Zhou
- Department of Anatomy and Neurobiology, School of Basic Medical Sciences, Central South University, Changsha 410013, Hunan Province, China
| | - Yan-Lin Wu
- Department of Anatomy and Neurobiology, School of Basic Medical Sciences, Central South University, Changsha 410013, Hunan Province, China
| | - Zhi-Xin Li
- Department of Anatomy and Neurobiology, School of Basic Medical Sciences, Central South University, Changsha 410013, Hunan Province, China
| | - Dan-Yi Zhang
- Department of Anatomy and Neurobiology, School of Basic Medical Sciences, Central South University, Changsha 410013, Hunan Province, China
| | - Yi-Chao Yang
- Department of Anatomy and Neurobiology, School of Basic Medical Sciences, Central South University, Changsha 410013, Hunan Province, China
| | - Rong-Hua Yang
- Department of Burns, Fo Shan Hospital of Sun Yat-Sen University, Foshan 528000, Guangdong Province, China
| | - Yong-Jun Hu
- Department of Cardiovascular Medicine, Hunan People's Hospital (the First Affiliated Hospital of Hunan Normal University, Changsha 410005, Hunan Province, China
| | - Kun Xiong
- Department of Anatomy and Neurobiology, School of Basic Medical Sciences, Central South University, Changsha 410013, Hunan Province, China
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Salicylic diamines selectively eliminate residual undifferentiated cells from pluripotent stem cell-derived cardiomyocyte preparations. Sci Rep 2021; 11:2391. [PMID: 33504837 PMCID: PMC7841182 DOI: 10.1038/s41598-021-81351-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Accepted: 12/14/2020] [Indexed: 02/06/2023] Open
Abstract
Clinical translation of pluripotent stem cell (PSC) derivatives is hindered by the tumorigenic risk from residual undifferentiated cells. Here, we identified salicylic diamines as potent agents exhibiting toxicity to murine and human PSCs but not to cardiomyocytes (CMs) derived from them. Half maximal inhibitory concentrations (IC50) of small molecules SM2 and SM6 were, respectively, 9- and 18-fold higher for human than murine PSCs, while the IC50 of SM8 was comparable for both PSC groups. Treatment of murine embryoid bodies in suspension differentiation cultures with the most effective small molecule SM6 significantly reduced PSC and non-PSC contamination and enriched CM populations that would otherwise be eliminated in genetic selection approaches. All tested salicylic diamines exerted their toxicity by inhibiting the oxygen consumption rate (OCR) in PSCs. No or only minimal and reversible effects on OCR, sarcomeric integrity, DNA stability, apoptosis rate, ROS levels or beating frequency were observed in PSC-CMs, although effects on human PSC-CMs seemed to be more deleterious at higher SM-concentrations. Teratoma formation from SM6-treated murine PSC-CMs was abolished or delayed compared to untreated cells. We conclude that salicylic diamines represent promising compounds for PSC removal and enrichment of CMs without the need for other selection strategies.
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Dai Y, Li J, Li M, Liu Z, Liu J, An L, Du F. Methyl-CpG-binding domain 3 (Mbd3) is an important regulator for apoptosis in mouse embryonic stem cells. Am J Transl Res 2020; 12:8147-8161. [PMID: 33437388 PMCID: PMC7791517] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Accepted: 11/30/2020] [Indexed: 06/12/2023]
Abstract
Methyl-CpG-binding domain 3 (Mbd3) is a core repressor complex component. Although Mbd3 is required for the pluripotency of embryonic stem cells (ES), the role of Mbd3 in mouse ES (mES) cell apoptosis remains undefined. In this study naïve-state mES were derived and maintained in the presence of a selective protein kinase C pathway inhibitor (PKCi; Gӧ6983) to study the function of Mbd3 during mES apoptosis. Mbd3 overexpression in mES decreased the total cell number and viability, and it also dramatically increased the rate of apoptosis. Further investigation of Mbd3 overexpression revealed a 3-fold increase in the proapoptotic/prosurvival protein ratio (Bax/Bcl-2) and elevated RNA expression levels of apoptosis-related genes, including Bim, Trail, Fasl, and caspase 3, with reduced Bcl-2 RNA expression levels. Removal of PKCi from the mES cell culture resulted in upregulated Mbd3 expression and apoptosis, similar to the effects of Mbd3 overexpression. Furthermore, specific knockdown of endogenous Mbd3 partially rescued the mES apoptosis induced by the removal of PKCi, thus increasing the total cell number and viability while decreasing the rate of apoptosis. Additionally, Bax, Bim, Trail, and caspase 3 RNA expression levels were partially reduced, and that of Bcl-2 was partially increased. Our findings support Mbd3 as a pivotal regulator of apoptosis in mES.
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Affiliation(s)
- Yujian Dai
- Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal UniversityNanjing 210046, PR China
| | - Jinshan Li
- Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal UniversityNanjing 210046, PR China
| | - Mingyang Li
- Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal UniversityNanjing 210046, PR China
| | - Zhihui Liu
- Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal UniversityNanjing 210046, PR China
| | - Jiao Liu
- Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal UniversityNanjing 210046, PR China
| | - Liyou An
- Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal UniversityNanjing 210046, PR China
| | - Fuliang Du
- Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal UniversityNanjing 210046, PR China
- Renova Life, Inc.College Park, Maryland 20742, USA
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8
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Chemical hypoxia induces apoptosis of human pluripotent stem cells by a NOXA-mediated HIF-1α and HIF-2α independent mechanism. Sci Rep 2020; 10:20653. [PMID: 33244167 PMCID: PMC7692563 DOI: 10.1038/s41598-020-77792-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Accepted: 11/17/2020] [Indexed: 02/06/2023] Open
Abstract
Human embryonic and induced pluripotent stem cells (hESCs and hiPSCs) are self-renewing human pluripotent stem cells (hPSCs) that can differentiate to a wide range of specialized cells. Notably, hPSCs enhance their undifferentiated state and self-renewal properties in hypoxia (5% O2). Although thoroughly analyzed, hypoxia implication in hPSCs death is not fully determined. In order to evaluate the effect of chemically mimicked hypoxia on hPSCs cell survival, we analyzed changes in cell viability and several aspects of apoptosis triggered by CoCl2 and dimethyloxalylglycine (DMOG). Mitochondrial function assays revealed a decrease in cell viability at 24 h post-treatments. Moreover, we detected chromatin condensation, DNA fragmentation and CASPASE-9 and 3 cleavages. In this context, we observed that P53, BNIP-3, and NOXA protein expression levels were significantly up-regulated at different time points upon chemical hypoxia induction. However, only siRNA-mediated downregulation of NOXA but not HIF-1α, HIF-2α, BNIP-3, and P53 did significantly affect the extent of cell death triggered by CoCl2 and DMOG in hPSCs. In conclusion, chemically mimicked hypoxia induces hPSCs cell death by a NOXA-mediated HIF-1α and HIF-2α independent mechanism.
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9
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Halliwell J, Barbaric I, Andrews PW. Acquired genetic changes in human pluripotent stem cells: origins and consequences. Nat Rev Mol Cell Biol 2020; 21:715-728. [DOI: 10.1038/s41580-020-00292-z] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/19/2020] [Indexed: 12/14/2022]
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10
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Tyurin-Kuzmin PA, Molchanov AY, Chechekhin VI, Ivanova AM, Kulebyakin KY. Metabolic Regulation of Mammalian Stem Cell Differentiation. BIOCHEMISTRY (MOSCOW) 2020; 85:264-278. [PMID: 32564731 DOI: 10.1134/s0006297920030025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Formation of normal tissue structure, homeostasis maintenance, and tissue damage repair require proliferation and differentiation of stem cells. A distinctive feature of these cells is a unique organization of metabolic pathways, in which contribution of energy production mechanisms to the general cellular metabolism is principally different from that in differentiated cells. Moreover, metabolic changes during differentiation of embryonic and postnatal stem cells have several specific features. The alterations in the stem cell metabolism are not simply consequences of cell differentiation, but also active regulators of this process. Metabolic enzymes and intermediates control and guide the maintenance of stemness, self-renewal, and differentiation of stem cells. The review discusses the patterns and molecular mechanisms of the switch in the metabolism of stem cells during their transition from the pluripotent to differentiated state with the special emphasis on how metabolic processes occurring in the stem cells regulate their functions, ability to differentiate, and the choice of the direction for development.
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Affiliation(s)
- P A Tyurin-Kuzmin
- Lomonosov Moscow State University, Faculty of Medicine, Department of Biochemistry and Molecular Medicine, Moscow, 119991, Russia.
| | - A Yu Molchanov
- Lomonosov Moscow State University, Faculty of Biology, Department of Embryology, Moscow, 119234, Russia
| | - V I Chechekhin
- Lomonosov Moscow State University, Faculty of Medicine, Department of Biochemistry and Molecular Medicine, Moscow, 119991, Russia
| | - A M Ivanova
- Lomonosov Moscow State University, Faculty of Medicine, Department of Biochemistry and Molecular Medicine, Moscow, 119991, Russia
| | - K Yu Kulebyakin
- Lomonosov Moscow State University, Faculty of Medicine, Department of Biochemistry and Molecular Medicine, Moscow, 119991, Russia
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Rasmussen ML, Gama V. A connection in life and death: The BCL-2 family coordinates mitochondrial network dynamics and stem cell fate. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2020; 353:255-284. [PMID: 32381177 DOI: 10.1016/bs.ircmb.2019.12.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The B cell CLL/lymphoma-2 (BCL-2) family of proteins control the mitochondrial pathway of apoptosis, also known as intrinsic apoptosis. Direct binding between members of the BCL-2 family regulates mitochondrial outer membrane permeabilization (MOMP) after an apoptotic insult. The ability of the cell to sense stress and translate it into a death signal has been a major theme of research for nearly three decades; however, other mechanisms by which the BCL-2 family coordinates cellular homeostasis beyond its role in initiating apoptosis are emerging. One developing area of research is understanding how the BCL-2 family of proteins regulate development using pluripotent stem cells as a model system. Understanding BCL-2 family-mediated regulation of mitochondrial homeostasis in cell death and beyond would uncover new facets of stem cell maintenance and differentiation potential.
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Affiliation(s)
- Megan L Rasmussen
- Department of Cell & Developmental Biology, Vanderbilt University, Nashville, TN, United States
| | - Vivian Gama
- Department of Cell & Developmental Biology, Vanderbilt University, Nashville, TN, United States; Neuroscience Program, Vanderbilt University Medical Center, Nashville, TN, United States; Vanderbilt Brain Institute, Vanderbilt University Medical Center, Nashville, TN, United States; Vanderbilt Center for Stem Cell Biology, Vanderbilt University, Nashville, TN, United States.
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12
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Abstract
In contrast to terminally differentiated cells, cancer cells and stem cells retain the ability to re-enter the cell cycle and proliferate. In order to proliferate, cells must increase the uptake and catabolism of nutrients to support anabolic cell growth. Intermediates of central metabolic pathways have emerged as key players that can influence cell differentiation 'decisions', processes relevant for both oncogenesis and normal development. Consequently, how cells rewire metabolic pathways to support proliferation may have profound consequences for cellular identity. Here, we discuss the metabolic programs that support proliferation and explore how metabolic states are intimately entwined with the cell fate decisions that characterize stem cells and cancer cells. By comparing the metabolism of pluripotent stem cells and cancer cells, we hope to illuminate common metabolic strategies as well as distinct metabolic features that may represent specialized adaptations to unique cellular demands.
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Affiliation(s)
- Andrew M Intlekofer
- Human Oncology & Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, NY, USA.
| | - Lydia W S Finley
- Cell Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY, USA.
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13
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Human Embryonic Stem Cells Acquire Responsiveness to TRAIL upon Exposure to Cisplatin. Stem Cells Int 2019; 2019:4279481. [PMID: 30805008 PMCID: PMC6360567 DOI: 10.1155/2019/4279481] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Revised: 11/19/2018] [Accepted: 11/29/2018] [Indexed: 12/21/2022] Open
Abstract
Tumor necrosis factor-related apoptosis-inducing ligand-TRAIL-is a protein operating as a ligand capable of inducing apoptosis particularly in cancerously transformed cells, while normal healthy cells are typically nonresponsive. We have previously demonstrated that pluripotent human embryonic stem cells (hESC) are also refractory to TRAIL, even though they express all canonical components of the death receptor-induced apoptosis pathway. In this study, we have examined a capacity of DNA damage to provoke sensitivity of hESC to TRAIL. The extent of DNA damage, behavior of molecules involved in apoptosis, and response of hESC to TRAIL were investigated. The exposure of hESC to 1 μM and 2 μM concentrations of cisplatin have led to the formation of 53BP1 and γH2AX foci, indicating the presence of double-strand breaks in DNA, without affecting the expression of proteins contributing to mitochondrial membrane integrity. Interestingly, cisplatin upregulated critical components of the extrinsic apoptotic pathway-initiator caspase 8, effector caspase 3, and the cell death receptors. The observed increase of expression of the extrinsic apoptotic pathway components was sufficient to sensitize hESC to TRAIL-induced apoptosis; immense cell dying accompanied by enhanced PARP cleavage, processing of caspase 8, and full activation of caspase 3 were all observed after the treatment combining cisplatin and TRAIL. Finally, we have demonstrated the central role of caspase 8 in this process, since its downregulation abrogated the sensitizing effect of cisplatin.
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14
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Dahan P, Lu V, Nguyen RMT, Kennedy SAL, Teitell MA. Metabolism in pluripotency: Both driver and passenger? J Biol Chem 2018; 294:5420-5429. [PMID: 29463682 DOI: 10.1074/jbc.tm117.000832] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Pluripotent stem cells (PSCs) are highly proliferative cells characterized by robust metabolic demands to power rapid division. For many years considered a passive component or "passenger" of cell-fate determination, cell metabolism is now starting to take center stage as a driver of cell fate outcomes. This review provides an update and analysis of our current understanding of PSC metabolism and its role in self-renewal, differentiation, and somatic cell reprogramming to pluripotency. Moreover, we present evidence on the active roles metabolism plays in shaping the epigenome to influence patterns of gene expression that may model key features of early embryonic development.
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Affiliation(s)
- Perrine Dahan
- From the Departments of Pathology and Laboratory Medicine and
| | - Vivian Lu
- Molecular and Medical Pharmacology and
| | | | - Stephanie A L Kennedy
- From the Departments of Pathology and Laboratory Medicine and.,the Department of Biology, California State University at Northridge, Northridge, California 91330
| | - Michael A Teitell
- From the Departments of Pathology and Laboratory Medicine and .,the California NanoSystems Institute.,Department of Bioengineering, and.,Molecular Biology Institute, UCLA, Los Angeles, California 90095, and.,Jonsson Comprehensive Cancer Center, David Geffen School of Medicine, UCLA, Los Angeles, California 90095.,the Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research, UCLA, Los Angeles, California 90095
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15
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Teotia P, Sharma S, Airan B, Mohanty S. Feeder & basic fibroblast growth factor-free culture of human embryonic stem cells: Role of conditioned medium from immortalized human feeders. Indian J Med Res 2018; 144:838-851. [PMID: 28474621 PMCID: PMC5433277 DOI: 10.4103/ijmr.ijmr_424_15] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND & OBJECTIVES Human embryonic stem cell (hESC) lines are commonly maintained on inactivated feeder cells, in the medium supplemented with basic fibroblast growth factor (bFGF). However, limited availability of feeder cells in culture, and the high cost of growth factors limit their use in scalable expansion of hESC cultures for clinical application. Here, we describe an efficient and cost-effective feeder and bFGF-free culture of hESCs using conditioned medium (CM) from immortalized feeder cells. METHODS KIND-1 hESC cell line was cultured in CM, collected from primary mouse embryonic fibroblast, human foreskin fibroblast (HFF) and immortalized HFF (I-HFF). Pluripotency of KIND-1 hESC cell line was confirmed by expression of genes, proteins and cell surface markers. RESULTS In culture, these cells retained normal morphology, expressed all cell surface markers, could differentiate to embryoid bodies upon culture in vitro. Furthermore, I-HFF feeder cells without supplementation of bFGF released ample amount of endogenous bFGF to maintain stemness of hESC cells. INTERPRETATION & CONCLUSIONS The study results described the use of CM from immortalized feeder cells as a consistent source and an efficient, inexpensive feeder-free culture system for the maintenance of hESCs. Moreover, it was possible to maintain hESCs without exogenous supplementation of bFGF. Thus, the study could be extended to scalable expansion of hESC cultures for therapeutic purposes.
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Affiliation(s)
- Pooja Teotia
- Stem Cell Facility, Cardio Thoracic Sciences Centre, All India Institute of Medical Sciences, New Delhi, India
| | - Shilpa Sharma
- Department of Pediatric Surgery, All India Institute of Medical Sciences, New Delhi, India
| | - Balram Airan
- Cardio Thoracic Vascular Surgery, All India Institute of Medical Sciences, New Delhi, India
| | - Sujata Mohanty
- Stem Cell Facility, Cardio Thoracic Sciences Centre, All India Institute of Medical Sciences, New Delhi, India
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16
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AKT/GSK3β signaling pathway is critically involved in human pluripotent stem cell survival. Sci Rep 2016; 6:35660. [PMID: 27762303 PMCID: PMC5071844 DOI: 10.1038/srep35660] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2015] [Accepted: 10/04/2016] [Indexed: 01/24/2023] Open
Abstract
Human embryonic and induced pluripotent stem cells are self-renewing pluripotent stem cells (PSC) that can differentiate into a wide range of specialized cells. Basic fibroblast growth factor is essential for PSC survival, stemness and self-renewal. PI3K/AKT pathway regulates cell viability and apoptosis in many cell types. Although it has been demonstrated that PI3K/AKT activation by bFGF is relevant for PSC stemness maintenance its role on PSC survival remains elusive. In this study we explored the molecular mechanisms involved in the regulation of PSC survival by AKT. We found that inhibition of AKT with three non-structurally related inhibitors (GSK690693, AKT inhibitor VIII and AKT inhibitor IV) decreased cell viability and induced apoptosis. We observed a rapid increase in phosphatidylserine translocation and in the extent of DNA fragmentation after inhibitors addition. Moreover, abrogation of AKT activity led to Caspase-9, Caspase-3, and PARP cleavage. Importantly, we demonstrated by pharmacological inhibition and siRNA knockdown that GSK3β signaling is responsible, at least in part, of the apoptosis triggered by AKT inhibition. Moreover, GSK3β inhibition decreases basal apoptosis rate and promotes PSC proliferation. In conclusion, we demonstrated that AKT activation prevents apoptosis, partly through inhibition of GSK3β, and thus results relevant for PSC survival.
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17
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Halevy T, Akov S, Bohndorf M, Mlody B, Adjaye J, Benvenisty N, Goldberg M. Chromosomal Instability and Molecular Defects in Induced Pluripotent Stem Cells from Nijmegen Breakage Syndrome Patients. Cell Rep 2016; 16:2499-511. [PMID: 27545893 DOI: 10.1016/j.celrep.2016.07.071] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2015] [Revised: 05/29/2016] [Accepted: 07/26/2016] [Indexed: 01/09/2023] Open
Abstract
Nijmegen breakage syndrome (NBS) results from the absence of the NBS1 protein, responsible for detection of DNA double-strand breaks (DSBs). NBS is characterized by microcephaly, growth retardation, immunodeficiency, and cancer predisposition. Here, we show successful reprogramming of NBS fibroblasts into induced pluripotent stem cells (NBS-iPSCs). Our data suggest a strong selection for karyotypically normal fibroblasts to go through the reprogramming process. NBS-iPSCs then acquire numerous chromosomal aberrations and show a delayed response to DSB induction. Furthermore, NBS-iPSCs display slower growth, mitotic inhibition, a reduced apoptotic response to stress, and abnormal cell-cycle-related gene expression. Importantly, NBS neural progenitor cells (NBS-NPCs) show downregulation of neural developmental genes, which seems to be mediated by P53. Our results demonstrate the importance of NBS1 in early human development, shed light on the molecular mechanisms underlying this severe syndrome, and further expand our knowledge of the genomic stress cells experience during the reprogramming process.
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Affiliation(s)
- Tomer Halevy
- The Azrieli Center for Stem Cells and Genetic Research, The Hebrew University, Givat-Ram, Jerusalem 91904, Israel; Department of Genetics, Institute of Life Sciences, The Hebrew University, Givat-Ram, Jerusalem 91904, Israel
| | - Shira Akov
- The Azrieli Center for Stem Cells and Genetic Research, The Hebrew University, Givat-Ram, Jerusalem 91904, Israel; Department of Genetics, Institute of Life Sciences, The Hebrew University, Givat-Ram, Jerusalem 91904, Israel
| | - Martina Bohndorf
- Institute for Stem Cell Research and Regenerative Medicine, Medical Faculty, Heinrich-Heine-University Duesseldorf, Moorenstrasse 5, 40225 Duesseldorf, Germany
| | - Barbara Mlody
- Institute for Stem Cell Research and Regenerative Medicine, Medical Faculty, Heinrich-Heine-University Duesseldorf, Moorenstrasse 5, 40225 Duesseldorf, Germany
| | - James Adjaye
- Institute for Stem Cell Research and Regenerative Medicine, Medical Faculty, Heinrich-Heine-University Duesseldorf, Moorenstrasse 5, 40225 Duesseldorf, Germany
| | - Nissim Benvenisty
- The Azrieli Center for Stem Cells and Genetic Research, The Hebrew University, Givat-Ram, Jerusalem 91904, Israel; Department of Genetics, Institute of Life Sciences, The Hebrew University, Givat-Ram, Jerusalem 91904, Israel.
| | - Michal Goldberg
- Department of Genetics, Institute of Life Sciences, The Hebrew University, Givat-Ram, Jerusalem 91904, Israel.
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18
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García CP, Videla Richardson GA, Dimopoulos NA, Fernandez Espinosa DD, Miriuka SG, Sevlever GE, Romorini L, Scassa ME. Human Pluripotent Stem Cells and Derived Neuroprogenitors Display Differential Degrees of Susceptibility to BH3 Mimetics ABT-263, WEHI-539 and ABT-199. PLoS One 2016; 11:e0152607. [PMID: 27030982 PMCID: PMC4816327 DOI: 10.1371/journal.pone.0152607] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2015] [Accepted: 03/16/2016] [Indexed: 12/11/2022] Open
Abstract
Human embryonic stem cells (hESCs) are hypersensitive to genotoxic stress and display lower survival ability relative to their differentiated progeny. Herein, we attempted to investigate the source of this difference by comparing the DNA damage responses triggered by the topoisomerase I inhibitor camptothecin, in hESCs, human induced pluripotent stem cells (hiPSCs) and hESCs-derived neuroprogenitors (NP). We observed that upon camptothecin exposure pluripotent stem cells underwent apoptosis more swiftly and at a higher rate than differentiated cells. However, the cellular response encompassing ataxia-telangiectasia mutated kinase activation and p53 phosphorylation both on serine 15 as well as on serine 46 resulted very similar among the aforementioned cell types. Importantly, we observed that hESCs and hiPSCs express lower levels of the anti-apoptotic protein Bcl-2 than NP. To assess whether Bcl-2 abundance could account for this differential response we treated cells with ABT-263, WEHI-539 and ABT-199, small molecules that preferentially target the BH3-binding pocket of Bcl-xL and/or Bcl-2 and reduce their ability to sequester pro-apoptotic factors. We found that in the absence of stress stimuli, NP exhibited a higher sensitivity to ABT- 263 and WEHI-539 than hESCs and hiPSCs. Conversely, all tested cell types appeared to be highly resistant to the Bcl-2 specific inhibitor, ABT-199. However, in all cases we determined that ABT-263 or WEHI-539 treatment exacerbated camptothecin-induced apoptosis. Importantly, similar responses were observed after siRNA-mediated down-regulation of Bcl-xL or Bcl-2. Taken together, our results suggest that Bcl-xL contrary to Bcl-2 contributes to ensure cell survival and also functions as a primary suppressor of DNA double-strand brake induced apoptosis both in pluripotent and derived NP cells. The emerging knowledge of the relative dependence of pluripotent and progenitor cells on Bcl-2 and Bcl-xL activities may help to predict cellular responses and potentially manipulate these cells for therapeutic purposes in the near future.
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Affiliation(s)
- Carolina Paola García
- Laboratorios de Investigación Aplicada a Neurociencias, LIAN-CONICET, Fundación FLENI, Ruta 9, Km 53, (B1625XAF) Escobar, Buenos Aires, Argentina
| | - Guillermo Agustín Videla Richardson
- Laboratorios de Investigación Aplicada a Neurociencias, LIAN-CONICET, Fundación FLENI, Ruta 9, Km 53, (B1625XAF) Escobar, Buenos Aires, Argentina
| | - Nicolás Alexis Dimopoulos
- Laboratorios de Investigación Aplicada a Neurociencias, LIAN-CONICET, Fundación FLENI, Ruta 9, Km 53, (B1625XAF) Escobar, Buenos Aires, Argentina
| | - Damián Darío Fernandez Espinosa
- Laboratorios de Investigación Aplicada a Neurociencias, LIAN-CONICET, Fundación FLENI, Ruta 9, Km 53, (B1625XAF) Escobar, Buenos Aires, Argentina
| | - Santiago Gabriel Miriuka
- Laboratorios de Investigación Aplicada a Neurociencias, LIAN-CONICET, Fundación FLENI, Ruta 9, Km 53, (B1625XAF) Escobar, Buenos Aires, Argentina
| | - Gustavo Emilio Sevlever
- Laboratorios de Investigación Aplicada a Neurociencias, LIAN-CONICET, Fundación FLENI, Ruta 9, Km 53, (B1625XAF) Escobar, Buenos Aires, Argentina
| | - Leonardo Romorini
- Laboratorios de Investigación Aplicada a Neurociencias, LIAN-CONICET, Fundación FLENI, Ruta 9, Km 53, (B1625XAF) Escobar, Buenos Aires, Argentina
| | - María Elida Scassa
- Laboratorios de Investigación Aplicada a Neurociencias, LIAN-CONICET, Fundación FLENI, Ruta 9, Km 53, (B1625XAF) Escobar, Buenos Aires, Argentina
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19
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TeSlaa T, Setoguchi K, Teitell MA. Mitochondria in human pluripotent stem cell apoptosis. Semin Cell Dev Biol 2016; 52:76-83. [PMID: 26828436 DOI: 10.1016/j.semcdb.2016.01.027] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2015] [Revised: 01/11/2016] [Accepted: 01/21/2016] [Indexed: 12/15/2022]
Abstract
Human pluripotent stem cells (hPSCs) have great potential in regenerative medicine because they can differentiate into any cell type in the body. Genome integrity is vital for human development and for high fidelity passage of genetic information across generations through the germ line. To ensure genome stability, hPSCs maintain a lower rate of mutation than somatic cells and undergo rapid apoptosis in response to DNA damage and additional cell stresses. Furthermore, cellular metabolism and the cell cycle are also differentially regulated between cells in pluripotent and differentiated states and can aid in protecting hPSCs against DNA damage and damaged cell propagation. Despite these safeguards, clinical use of hPSC derivatives could be compromised by tumorigenic potential and possible malignant transformation from failed to differentiate cells. Since hPSCs and mature cells differentially respond to cell stress, it may be possible to specifically target undifferentiated cells for rapid apoptosis in mixed cell populations to enable safer use of hPSC-differentiated cells in patients.
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Affiliation(s)
- Tara TeSlaa
- Molecular Biology Institute, University of California, Los Angeles, CA 90095, USA
| | - Kiyoko Setoguchi
- Department of Pathology and Laboratory Medicine, University of California, Los Angeles, CA 90095, USA
| | - Michael A Teitell
- Molecular Biology Institute, University of California, Los Angeles, CA 90095, USA; Department of Pathology and Laboratory Medicine, University of California, Los Angeles, CA 90095, USA; Department of Bioengineering, Department of Pediatrics, California NanoSystems Institute, Jonsson Comprehensive Cancer Center, and Broad Center of Regenerative Medicine and Stem Cell Research, University of California, Los Angeles, CA 90095, USA.
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20
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Choi SW, Shin TH, Uddin MH, Shin JH, Kang TW, Lee BC, Kim HS, Seo Y, Shams S, Jung YK, Kang KS. STB-HO, a novel mica fine particle, inhibits the teratoma-forming ability of human embryonic stem cells after in vivo transplantation. Oncotarget 2016; 7:2684-95. [PMID: 26646796 PMCID: PMC4823064 DOI: 10.18632/oncotarget.6472] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Accepted: 11/25/2015] [Indexed: 01/01/2023] Open
Abstract
Although pluripotent stem cell (PSC) therapy has advantages for clinical applications because of the self-renewal and multi-lineage differentiation abilities of PSCs, it also has disadvantages in terms of the potential for PSCs to undergo malignant transformation or unexpected differentiation. The prevention of teratoma formation is the largest hurdle of all. Despite intensive studies that have investigated ways to block teratomas, such methods have yet to be further developed for clinical use. Here, a new approach has focused on exerting anti-tumorigenic effects using a novel mica fine particle (MFP) designated STB-HO. Treatment with STB-HO regulated pluripotency- and apoptosis-related genes in differentiating human embryonic stem (hES) cells, while there is no effects in undifferentiated hES cells. In particular, STB-HO blocked the anti-apoptotic gene BIRC5 and activated p53, p21 and the pro-apoptotic proteins Bim, Puma and p-Bad during early spontaneous differentiation. Moreover, STB-HO-pretreated differentiating hES cells did not give rise to teratomas following in vivo stem cell transplantation. Our in vitro and in vivo results suggest a method for teratoma prevention in the context of PSC-derived cell transplantation. This novel MFP could break through the limitations of PSC therapy.
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Affiliation(s)
- Soon Won Choi
- Adult Stem Cell Research Center, College of Veterinary Medicine, Seoul National University, Seoul, Republic of Korea.,Research Institute for Veterinary Science, College of Veterinary Medicine, Seoul National University, Seoul, Republic of Korea
| | - Tae-Hoon Shin
- Adult Stem Cell Research Center, College of Veterinary Medicine, Seoul National University, Seoul, Republic of Korea.,Research Institute for Veterinary Science, College of Veterinary Medicine, Seoul National University, Seoul, Republic of Korea
| | - Md Hafiz Uddin
- Adult Stem Cell Research Center, College of Veterinary Medicine, Seoul National University, Seoul, Republic of Korea.,Research Institute for Veterinary Science, College of Veterinary Medicine, Seoul National University, Seoul, Republic of Korea
| | - Ji-Hee Shin
- Adult Stem Cell Research Center, College of Veterinary Medicine, Seoul National University, Seoul, Republic of Korea.,Research Institute for Veterinary Science, College of Veterinary Medicine, Seoul National University, Seoul, Republic of Korea
| | - Tae-Wook Kang
- Research Institute for Veterinary Science, College of Veterinary Medicine, Seoul National University, Seoul, Republic of Korea.,Institute for Stem Cell and Regenerative Medicine in Kangstem Biotech, Biomedical Science Building, College of Veterinary Medicine, Seoul National University, Seoul, Republic of Korea
| | - Byung-Chul Lee
- Adult Stem Cell Research Center, College of Veterinary Medicine, Seoul National University, Seoul, Republic of Korea.,Research Institute for Veterinary Science, College of Veterinary Medicine, Seoul National University, Seoul, Republic of Korea
| | - Hyung-Sik Kim
- Adult Stem Cell Research Center, College of Veterinary Medicine, Seoul National University, Seoul, Republic of Korea.,Research Institute for Veterinary Science, College of Veterinary Medicine, Seoul National University, Seoul, Republic of Korea
| | - Yoojin Seo
- Adult Stem Cell Research Center, College of Veterinary Medicine, Seoul National University, Seoul, Republic of Korea.,Research Institute for Veterinary Science, College of Veterinary Medicine, Seoul National University, Seoul, Republic of Korea
| | - Sulaiman Shams
- Adult Stem Cell Research Center, College of Veterinary Medicine, Seoul National University, Seoul, Republic of Korea.,Stem Cells Regenerative Medicine Lab, Department of Biochemistry, Abdul Wali Khan University, Khyber Pakhtunkhwa, Pakistan
| | - Yeon-Kwon Jung
- Seobong BioBesstech Co., Ltd., Yeoksam-dong, Kangnam-gu, Seoul, Republic of Korea
| | - Kyung-Sun Kang
- Adult Stem Cell Research Center, College of Veterinary Medicine, Seoul National University, Seoul, Republic of Korea.,Research Institute for Veterinary Science, College of Veterinary Medicine, Seoul National University, Seoul, Republic of Korea
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21
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Dannenmann B, Lehle S, Hildebrand DG, Kübler A, Grondona P, Schmid V, Holzer K, Fröschl M, Essmann F, Rothfuss O, Schulze-Osthoff K. High glutathione and glutathione peroxidase-2 levels mediate cell-type-specific DNA damage protection in human induced pluripotent stem cells. Stem Cell Reports 2015; 4:886-98. [PMID: 25937369 PMCID: PMC4437487 DOI: 10.1016/j.stemcr.2015.04.004] [Citation(s) in RCA: 66] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2014] [Revised: 04/03/2015] [Accepted: 04/03/2015] [Indexed: 12/20/2022] Open
Abstract
Pluripotent stem cells must strictly maintain genomic integrity to prevent transmission of mutations. In human induced pluripotent stem cells (iPSCs), we found that genome surveillance is achieved via two ways, namely, a hypersensitivity to apoptosis and a very low accumulation of DNA lesions. The low apoptosis threshold was mediated by constitutive p53 expression and a marked upregulation of proapoptotic p53 target genes of the BCL-2 family, ensuring the efficient iPSC removal upon genotoxic insults. Intriguingly, despite the elevated apoptosis sensitivity, both mitochondrial and nuclear DNA lesions induced by genotoxins were less frequent in iPSCs compared to fibroblasts. Gene profiling identified that mRNA expression of several antioxidant proteins was considerably upregulated in iPSCs. Knockdown of glutathione peroxidase-2 and depletion of glutathione impaired protection against DNA lesions. Thus, iPSCs ensure genomic integrity through enhanced apoptosis induction and increased antioxidant defense, contributing to protection against DNA damage. The iPSCs maintain genomic integrity by DNA damage protection and rapid apoptosis Apoptosis hypersensitivity is mediated by p53 and proapoptotic BCL-2 proteins The iPSCs also display a strongly elevated antioxidant defense Depletion of glutathione and GPX2 impairs DNA damage protection in iPSCs
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Affiliation(s)
- Benjamin Dannenmann
- Department of Molecular Medicine, Interfaculty Institute for Biochemistry, University of Tübingen, 72076 Tübingen, Germany
| | - Simon Lehle
- Department of Molecular Medicine, Interfaculty Institute for Biochemistry, University of Tübingen, 72076 Tübingen, Germany
| | - Dominic G Hildebrand
- Department of Molecular Medicine, Interfaculty Institute for Biochemistry, University of Tübingen, 72076 Tübingen, Germany
| | - Ayline Kübler
- Department of Molecular Medicine, Interfaculty Institute for Biochemistry, University of Tübingen, 72076 Tübingen, Germany
| | - Paula Grondona
- Department of Molecular Medicine, Interfaculty Institute for Biochemistry, University of Tübingen, 72076 Tübingen, Germany
| | - Vera Schmid
- Department of Molecular Medicine, Interfaculty Institute for Biochemistry, University of Tübingen, 72076 Tübingen, Germany
| | - Katharina Holzer
- Department of Molecular Medicine, Interfaculty Institute for Biochemistry, University of Tübingen, 72076 Tübingen, Germany
| | - Mirjam Fröschl
- Department of Molecular Medicine, Interfaculty Institute for Biochemistry, University of Tübingen, 72076 Tübingen, Germany
| | - Frank Essmann
- Department of Molecular Medicine, Interfaculty Institute for Biochemistry, University of Tübingen, 72076 Tübingen, Germany
| | - Oliver Rothfuss
- Department of Molecular Medicine, Interfaculty Institute for Biochemistry, University of Tübingen, 72076 Tübingen, Germany
| | - Klaus Schulze-Osthoff
- Department of Molecular Medicine, Interfaculty Institute for Biochemistry, University of Tübingen, 72076 Tübingen, Germany; German Cancer Consortium (DKTK) and German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany.
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22
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Rapti K, Stillitano F, Karakikes I, Nonnenmacher M, Weber T, Hulot JS, Hajjar RJ. Effectiveness of gene delivery systems for pluripotent and differentiated cells. MOLECULAR THERAPY-METHODS & CLINICAL DEVELOPMENT 2015; 2:14067. [PMID: 26052535 PMCID: PMC4449028 DOI: 10.1038/mtm.2014.67] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/28/2014] [Revised: 11/13/2014] [Accepted: 12/01/2014] [Indexed: 12/19/2022]
Abstract
Human embryonic stem cells (hESC) and induced pluripotent stem cells (hiPSC) assert a great future for the cardiovascular diseases, both to study them and to explore therapies. However, a comprehensive assessment of the viral vectors used to modify these cells is lacking. In this study, we aimed to compare the transduction efficiency of recombinant adeno-associated vectors (AAV), adenoviruses and lentiviral vectors in hESC, hiPSC, and the derived cardiomyocytes. In undifferentiated cells, adenoviral and lentiviral vectors were superior, whereas in differentiated cells AAV surpassed at least lentiviral vectors. We also tested four AAV serotypes, 1, 2, 6, and 9, of which 2 and 6 were superior in their transduction efficiency. Interestingly, we observed that AAVs severely diminished the viability of undifferentiated cells, an effect mediated by induction of cell cycle arrest genes and apoptosis. Furthermore, we show that the transduction efficiency of the different viral vectors correlates with the abundance of their respective receptors. Finally, adenoviral delivery of the calcium-transporting ATPase SERCA2a to hESC and hiPSC-derived cardiomyocytes successfully resulted in faster calcium reuptake. In conclusion, adenoviral vectors prove to be efficient for both differentiated and undifferentiated lines, whereas lentiviral vectors are more applicable to undifferentiated cells and AAVs to differentiated cells.
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Affiliation(s)
- Kleopatra Rapti
- Cardiovascular Research Center, Mount Sinai School of Medicine , New York, New York, USA
| | - Francesca Stillitano
- Cardiovascular Research Center, Mount Sinai School of Medicine , New York, New York, USA
| | - Ioannis Karakikes
- Cardiovascular Research Center, Mount Sinai School of Medicine , New York, New York, USA
| | - Mathieu Nonnenmacher
- Cardiovascular Research Center, Mount Sinai School of Medicine , New York, New York, USA
| | - Thomas Weber
- Cardiovascular Research Center, Mount Sinai School of Medicine , New York, New York, USA
| | - Jean-Sebastian Hulot
- Cardiovascular Research Center, Mount Sinai School of Medicine , New York, New York, USA ; Institute for Cardiac Metabolism and Nutrition, Universite Pierre et Marie Curie-Paris 6 , Paris, France
| | - Roger J Hajjar
- Cardiovascular Research Center, Mount Sinai School of Medicine , New York, New York, USA
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23
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Liu JC, Lerou PH, Lahav G. Stem cells: balancing resistance and sensitivity to DNA damage. Trends Cell Biol 2014; 24:268-74. [PMID: 24721782 PMCID: PMC4342985 DOI: 10.1016/j.tcb.2014.03.002] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2013] [Revised: 02/28/2014] [Accepted: 03/04/2014] [Indexed: 01/01/2023]
Abstract
Embryonic stem cells (ESCs) are known to be very sensitive to DNA damage and undergo rapid apoptosis even after low-damage doses. By contrast, adult stem cells show variable sensitivity to damage. Here we describe the multiple pathways that have been proposed to affect the sensitivity of stem cells to damage, including proximity to the apoptotic threshold (mitochondrial priming) and the p53 signaling pathway, through activation of transcription or direct interaction with proapoptotic proteins in the cytoplasm. We also discuss which cellular factors might connect mitochondrial priming with pluripotency and the potential therapeutic advances that can be achieved by better understanding of the molecular mechanisms leading to sensitivity or resistance of embryonic or adult stem cells from different tissues.
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Affiliation(s)
- Julia C Liu
- Department of Systems Biology, Harvard Medical School, Boston, MA 02115, USA
| | - Paul H Lerou
- Department of Pediatric Newborn Medicine, Brigham and Women's Hospital, Boston, MA 02115, USA; Department of Medicine, Division of Genetics, Brigham and Women's Hospital, Boston, MA 02115, USA
| | - Galit Lahav
- Department of Systems Biology, Harvard Medical School, Boston, MA 02115, USA.
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24
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Wang J, Guo X, Lui M, Chu PJ, Yoo J, Chang M, Yen Y. Identification of a distinct small cell population from human bone marrow reveals its multipotency in vivo and in vitro. PLoS One 2014; 9:e85112. [PMID: 24465489 PMCID: PMC3894949 DOI: 10.1371/journal.pone.0085112] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2013] [Accepted: 11/30/2013] [Indexed: 01/10/2023] Open
Abstract
Small stem cells, such as spore-like cells, blastomere-like stem cells (BLSCs), and very-small embryonic-like stem cells (VSELs) have been described in recent studies, although their multipotency in human tissues has not yet been confirmed. Here, we report the discovery of adult multipotent stem cells derived from human bone marrow, which we call StemBios (SB) cells. These isolated SB cells are smaller than 6 ìm and are DAPI+ and Lgr5+ (Leucine-Rich Repeat Containing G Protein-Coupled Receptor 5). Because Lgr5 has been characterized as a stem cell marker in the intestine, we hypothesized that SB cells may have a similar function. In vivo cell tracking assays confirmed that SB cells give rise to three types of cells, and in vitro studies demonstrated that SB cells cultured in proprietary media are able to grow to 6–25 ìm in size. Once the SB cells have attached to the wells, they differentiate into different cell lineages upon exposure to specific differentiation media. We are the first to demonstrate that stem cells smaller than 6 ìm can differentiate both in vivo and in vitro. In the future, we hope that SB cells will be used therapeutically to cure degenerative diseases.
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Affiliation(s)
- James Wang
- StemBios Technologies, Inc., Monterey Park, California, United States of America
- * E-mail: (YY); (JW)
| | - Xiaoyu Guo
- StemBios Technologies, Inc., Monterey Park, California, United States of America
| | - Monica Lui
- StemBios Technologies, Inc., Monterey Park, California, United States of America
| | - Pei-Ju Chu
- StemBios Technologies, Inc., Monterey Park, California, United States of America
| | - Jennifer Yoo
- StemBios Technologies, Inc., Monterey Park, California, United States of America
| | - Megan Chang
- StemBios Technologies, Inc., Monterey Park, California, United States of America
| | - Yun Yen
- Board Member of the Scientific Advisory Board, StemBios Technologies, Inc., Monterey Park, California, United States of America
- * E-mail: (YY); (JW)
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25
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Nagahara Y, Morita M, Nakata T, Iba A, Shinomiya T. Loss of Bcl-2 expression correlates with increasing sensitivity to apoptosis in differentiating ES cells. Cell Biol Int 2013; 38:381-7. [DOI: 10.1002/cbin.10214] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2013] [Accepted: 10/21/2013] [Indexed: 01/25/2023]
Affiliation(s)
- Yukitoshi Nagahara
- Division of Life Science and Engineering, College of Science and Engineering; Tokyo Denki University; Hatoyama, Hiki-gun Saitama 350-0394 Japan
| | - Misa Morita
- Division of Life Science and Engineering, College of Science and Engineering; Tokyo Denki University; Hatoyama, Hiki-gun Saitama 350-0394 Japan
| | - Tsubasa Nakata
- Division of Life Science and Engineering, College of Science and Engineering; Tokyo Denki University; Hatoyama, Hiki-gun Saitama 350-0394 Japan
| | - Akitoshi Iba
- Division of Life Science and Engineering, College of Science and Engineering; Tokyo Denki University; Hatoyama, Hiki-gun Saitama 350-0394 Japan
| | - Takahisa Shinomiya
- Division of Life Science and Engineering, College of Science and Engineering; Tokyo Denki University; Hatoyama, Hiki-gun Saitama 350-0394 Japan
- Department of Pharmaceutical Sciences, Faculty of Pharmaceutical Sciences; Aomori University; 2-3-1 Koubata, Aomori Aomori 030-0943 Japan
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26
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Vinarsky V, Krivanek J, Rankel L, Nahacka Z, Barta T, Jaros J, Andera L, Hampl A. Human embryonic and induced pluripotent stem cells express TRAIL receptors and can be sensitized to TRAIL-induced apoptosis. Stem Cells Dev 2013; 22:2964-74. [PMID: 23806100 DOI: 10.1089/scd.2013.0057] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Death ligands and their tumor necrosis factor receptor (TNFR) family receptors are the best-characterized and most efficient inducers of apoptotic signaling in somatic cells. In this study, we analyzed whether these prototypic activators of apoptosis are also expressed and able to be activated in human pluripotent stem cells. We examined human embryonic stem cells (hESC) and human-induced pluripotent stem cells (hiPSC) and found that both cell types express primarily TNF-related apoptosis-inducing ligand (TRAIL) receptors and TNFR1, but very low levels of Fas/CD95. We also found that although hESC and hiPSC contain all the proteins required for efficient induction and progression of extrinsic apoptotic signaling, they are resistant to TRAIL-induced apoptosis. However, both hESC and hiPSC can be sensitized to TRAIL-induced apoptosis by co-treatment with protein synthesis inhibitors such as the anti-leukemia drug homoharringtonine (HHT). HHT treatment led to suppression of cellular FLICE inhibitory protein (cFLIP) and Mcl-1 expression and, in combination with TRAIL, enhanced processing of caspase-8 and full activation of caspase-3. cFLIP likely represents an important regulatory node, as its shRNA-mediated down-regulation significantly sensitized hESC to TRAIL-induced apoptosis. Thus, we provide the first evidence that, irrespective of their origin, human pluripotent stem cells express canonical components of the extrinsic apoptotic system and on stress can activate death receptor-mediated apoptosis.
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Affiliation(s)
- Vladimir Vinarsky
- 1 Department of Histology and Embryology, Faculty of Medicine, Masaryk University , Brno, Czech Republic
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Lessons learned about human stem cell responses to ionizing radiation exposures: a long road still ahead of us. Int J Mol Sci 2013; 14:15695-723. [PMID: 23899786 PMCID: PMC3759881 DOI: 10.3390/ijms140815695] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2013] [Revised: 07/15/2013] [Accepted: 07/17/2013] [Indexed: 12/16/2022] Open
Abstract
Human stem cells (hSC) possess several distinct characteristics that set them apart from other cell types. First, hSC are self-renewing, capable of undergoing both asymmetric and symmetric cell divisions. Second, these cells can be coaxed to differentiate into various specialized cell types and, as such, hold great promise for regenerative medicine. Recent progresses in hSC biology fostered the characterization of the responses of hSC to genotoxic stresses, including ionizing radiation (IR). Here, we examine how different types of hSC respond to IR, with a special emphasis on their radiosensitivity, cell cycle, signaling networks, DNA damage response (DDR) and DNA repair. We show that human embryonic stem cells (hESCs) possess unique characteristics in how they react to IR that clearly distinguish these cells from all adult hSC studied thus far. On the other hand, a manifestation of radiation injuries/toxicity in human bodies may depend to a large extent on hSC populating corresponding tissues, such as human mesenchymal stem cells (hMSC), human hematopoietic stem cells (hHSC), neural hSC, intestine hSC, etc. We discuss here that hSC responses to IR differ notably across many types of hSC which may represent the distinct roles these cells play in development, regeneration and/or maintenance of homeostasis.
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Gutekunst M, Mueller T, Weilbacher A, Dengler MA, Bedke J, Kruck S, Oren M, Aulitzky WE, van der Kuip H. Cisplatin Hypersensitivity of Testicular Germ Cell Tumors Is Determined by High Constitutive Noxa Levels Mediated by Oct-4. Cancer Res 2013; 73:1460-9. [DOI: 10.1158/0008-5472.can-12-2876] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Gogada R, Yadav N, Liu J, Tang S, Zhang D, Schneider A, Seshadri A, Sun L, Aldaz CM, Tang DG, Chandra D. Bim, a proapoptotic protein, up-regulated via transcription factor E2F1-dependent mechanism, functions as a prosurvival molecule in cancer. J Biol Chem 2012; 288:368-81. [PMID: 23152504 DOI: 10.1074/jbc.m112.386102] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Proapoptotic Bcl-2 homology 3-only protein Bim plays an important role in Bax/Bak-mediated cytochrome c release and apoptosis. Here, we provide evidence for a novel prosurvival function of Bim in cancer cells. Bim was constitutively overexpressed in multiple prostate and breast cancer cells as well as in primary tumor cells. Quantitative real time PCR analysis showed that Bim was transcriptionally up-regulated. We have identified eight endogenous E2F1-binding sites on the Bim promoter using in silico analysis. Luciferase assay demonstrated that Bim expression was E2F1-dependent as mutation of the E2F1-binding sites on the Bim promoter inhibited luciferase activities. In support, E2F1 silencing led to the loss of Bim expression in cancer cells. Bim primarily localized to mitochondrial and cytoskeleton-associated fractions. Bim silencing or microinjection of anti-Bim antibodies into the cell cytoplasm resulted in cell rounding, detachment, and subsequent apoptosis. We observed up-regulation of prosurvival proteins Bcl-xL and Mcl-1, which sequester Bim in cancer cells. In addition, a phosphorylated form of Bim was also elevated in cancer cells. These findings suggest that the constitutively overexpressed Bim may function as a prosurvival molecule in epithelial cancer cells, and phosphorylation and association with Bcl-xL/Mcl-1 block its proapoptotic functions.
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Affiliation(s)
- Raghu Gogada
- Department of Pharmacology and Therapeutics, Roswell Park Cancer Institute, Buffalo, New York 14263, USA
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Determinants of human adipose tissue gene expression: impact of diet, sex, metabolic status, and cis genetic regulation. PLoS Genet 2012; 8:e1002959. [PMID: 23028366 PMCID: PMC3459935 DOI: 10.1371/journal.pgen.1002959] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2012] [Accepted: 07/25/2012] [Indexed: 12/17/2022] Open
Abstract
Weight control diets favorably affect parameters of the metabolic syndrome and delay the onset of diabetic complications. The adaptations occurring in adipose tissue (AT) are likely to have a profound impact on the whole body response as AT is a key target of dietary intervention. Identification of environmental and individual factors controlling AT adaptation is therefore essential. Here, expression of 271 transcripts, selected for regulation according to obesity and weight changes, was determined in 515 individuals before, after 8-week low-calorie diet-induced weight loss, and after 26-week ad libitum weight maintenance diets. For 175 genes, opposite regulation was observed during calorie restriction and weight maintenance phases, independently of variations in body weight. Metabolism and immunity genes showed inverse profiles. During the dietary intervention, network-based analyses revealed strong interconnection between expression of genes involved in de novo lipogenesis and components of the metabolic syndrome. Sex had a marked influence on AT expression of 88 transcripts, which persisted during the entire dietary intervention and after control for fat mass. In women, the influence of body mass index on expression of a subset of genes persisted during the dietary intervention. Twenty-two genes revealed a metabolic syndrome signature common to men and women. Genetic control of AT gene expression by cis signals was observed for 46 genes. Dietary intervention, sex, and cis genetic variants independently controlled AT gene expression. These analyses help understanding the relative importance of environmental and individual factors that control the expression of human AT genes and therefore may foster strategies aimed at improving AT function in metabolic diseases. In obesity, an excess of adipose tissue is associated with dyslipidemia and diabetic complications. Gene expression is under the control of various genetic and environmental factors. As a central organ for the control of metabolic disturbances in conditions of both weight gain and loss, a comprehensive understanding of the control of adipose tissue gene expression is of paramount interest. We analyzed adipose tissue gene expression in obese individuals from the DiOGenes protocol, one of the largest dietary interventions worldwide. We found evidence for composite control of adipose tissue gene expression by nutrition, metabolic syndrome, body mass index, sex, and genotype with two main novel features. First, we observed a preeminent effect of sex on adipose tissue gene expression, which was independent of nutritional status, fat mass, and sex chromosomes. Second, the control of gene expression by cis genetic factors was unaffected by sex and nutritional status. Altogether, the effects of the investigated factors were most often independent of each other. Comprehension of the relative importance of environmental and individual factors that control the expression of human adipose tissue genes may help deciphering strategies aimed at controlling adipose tissue function during metabolic disorders.
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Smith AJ, Nelson NG, Oommen S, Hartjes KA, Folmes CD, Terzic A, Nelson TJ. Apoptotic susceptibility to DNA damage of pluripotent stem cells facilitates pharmacologic purging of teratoma risk. Stem Cells Transl Med 2012. [PMID: 23197662 DOI: 10.5966/sctm.2012-0066] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Pluripotent stem cells have been the focus of bioengineering efforts designed to generate regenerative products, yet harnessing therapeutic capacity while minimizing risk of dysregulated growth remains a challenge. The risk of residual undifferentiated stem cells within a differentiated progenitor population requires a targeted approach to eliminate contaminating cells prior to delivery. In this study we aimed to validate a toxicity strategy that could selectively purge pluripotent stem cells in response to DNA damage and avoid risk of uncontrolled cell growth upon transplantation. Compared with somatic cell types, embryonic stem cells and induced pluripotent stem cells displayed hypersensitivity to apoptotic induction by genotoxic agents. Notably, hypersensitivity in pluripotent stem cells was stage-specific and consistently lost upon in vitro differentiation, with the mean half-maximal inhibitory concentration increasing nearly 2 orders of magnitude with tissue specification. Quantitative polymerase chain reaction and Western blotting demonstrated that the innate response was mediated through upregulation of the BH3-only protein Puma in both natural and induced pluripotent stem cells. Pretreatment with genotoxic etoposide purged hypersensitive pluripotent stem cells to yield a progenitor population refractory to teratoma formation upon transplantation. Collectively, this study exploits a hypersensitive apoptotic response to DNA damage within pluripotent stem cells to decrease risk of dysregulated growth and augment the safety profile of transplant-ready, bioengineered progenitor cells.
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Affiliation(s)
- Alyson J Smith
- Department of Medicine and Transplant Center, Mayo Clinic, Rochester, MN 55905, USA
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Suvorova II, Katolikova NV, Pospelov VA. New insights into cell cycle regulation and DNA damage response in embryonic stem cells. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2012; 299:161-98. [PMID: 22959303 DOI: 10.1016/b978-0-12-394310-1.00004-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Embryonic stem cells (ESCs) have unlimited proliferative potential, while retaining the ability to differentiate into descendants of all three embryonic layers. High proliferation rate of ESCs is accompanied by a shortening of the G(1) phase and the lack of G(1) checkpoint following DNA damage. The absence of G(1) arrest in ESCs after DNA damage is likely caused by a dysfunction of the p53-dependent p21Waf1 pathway that is a key event for the maintenance of pluripotency. There are controversial data on the functional status of p53, but it is well established that one of the key p53 target-p21Waf1-is expressed in ESCs at a very low level. Despite the lack of G(1) checkpoint, ESCs are capable to repair DNA defects; moreover the DNA damage response (DDR) signaling operates very effectively throughout the cell cycle. This review covers also the results obtained with the reprogramming of somatic cells into the induced pluripotent stem cells, for which have been shown that a partial dysfunction of the p53Waf1 pathway increases the frequency of generation of pluripotent cells. In summary, these results indicate that the G(1) checkpoint control and DDR are distinct from somatic cells and their status is tightly connected with maintaining of pluripotency and self-renewal.
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Affiliation(s)
- Irina I Suvorova
- Institute of Cytology, Russian Academy of Sciences, St Petersburg, Russia
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