151
|
Garcia-Guerra L, Vila-Bedmar R, Carrasco-Rando M, Cruces-Sande M, Martín M, Ruiz-Gómez A, Ruiz-Gómez M, Lorenzo M, Fernández-Veledo S, Mayor F, Murga C, Nieto-Vázquez I. Skeletal muscle myogenesis is regulated by G protein-coupled receptor kinase 2. J Mol Cell Biol 2014; 6:299-311. [PMID: 24927997 DOI: 10.1093/jmcb/mju025] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
G protein-coupled receptor kinase 2 (GRK2) is an important serine/threonine-kinase regulating different membrane receptors and intracellular proteins. Attenuation of Drosophila Gprk2 in embryos or adult flies induced a defective differentiation of somatic muscles, loss of fibers, and a flightless phenotype. In vertebrates, GRK2 hemizygous mice contained less but more hypertrophied skeletal muscle fibers than wild-type littermates. In C2C12 myoblasts, overexpression of a GRK2 kinase-deficient mutant (K220R) caused precocious differentiation of cells into immature myotubes, which were wider in size and contained more fused nuclei, while GRK2 overexpression blunted differentiation. Moreover, p38MAPK and Akt pathways were activated at an earlier stage and to a greater extent in K220R-expressing cells or upon kinase downregulation, while the activation of both kinases was impaired in GRK2-overexpressing cells. The impaired differentiation and fewer fusion events promoted by enhanced GRK2 levels were recapitulated by a p38MAPK mutant, which was able to mimic the inhibitory phosphorylation of p38MAPK by GRK2, whereas the blunted differentiation observed in GRK2-expressing clones was rescued in the presence of a constitutively active upstream stimulator of the p38MAPK pathway. These results suggest that balanced GRK2 function is necessary for a timely and complete myogenic process.
Collapse
Affiliation(s)
- Lucia Garcia-Guerra
- Department of Biochemistry and Molecular Biology II, School of Pharmacy, Complutense University, 28040 Madrid, Spain CIBER de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), 08017 Barcelona, Spain Instituto de Investigaciones Biomédicas Alberto Sols (CSIC-UAM), 28029 Madrid, Spain CIBER de enfermedades neurodegenerativas (CIBERNED), 28049 Madrid, Spain
| | - Rocío Vila-Bedmar
- Departament of Molecular Biology and Centro de Biología Molecular Severo Ochoa (CSIC-UAM), 28049 Madrid, Spain Instituto de Investigación Sanitaria la Princesa, 28006 Madrid, Spain
| | | | - Marta Cruces-Sande
- Departament of Molecular Biology and Centro de Biología Molecular Severo Ochoa (CSIC-UAM), 28049 Madrid, Spain Instituto de Investigación Sanitaria la Princesa, 28006 Madrid, Spain
| | - Mercedes Martín
- Centro de Biología Molecular Severo Ochoa (UAM-CSIC), 28049 Madrid, Spain
| | - Ana Ruiz-Gómez
- Centro de Biología Molecular Severo Ochoa (UAM-CSIC), 28049 Madrid, Spain
| | - Mar Ruiz-Gómez
- Centro de Biología Molecular Severo Ochoa (UAM-CSIC), 28049 Madrid, Spain
| | - Margarita Lorenzo
- Department of Biochemistry and Molecular Biology II, School of Pharmacy, Complutense University, 28040 Madrid, Spain CIBER de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), 08017 Barcelona, Spain
| | - Sonia Fernández-Veledo
- CIBER de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), 08017 Barcelona, Spain Hospital Universitari de Tarragona Joan XXIII. IISPV. Universitat Rovira i Virgili, 43007 Tarragona, Spain
| | - Federico Mayor
- Departament of Molecular Biology and Centro de Biología Molecular Severo Ochoa (CSIC-UAM), 28049 Madrid, Spain Instituto de Investigación Sanitaria la Princesa, 28006 Madrid, Spain
| | - Cristina Murga
- Departament of Molecular Biology and Centro de Biología Molecular Severo Ochoa (CSIC-UAM), 28049 Madrid, Spain Instituto de Investigación Sanitaria la Princesa, 28006 Madrid, Spain
| | - Iria Nieto-Vázquez
- Department of Biochemistry and Molecular Biology II, School of Pharmacy, Complutense University, 28040 Madrid, Spain CIBER de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), 08017 Barcelona, Spain
| |
Collapse
|
152
|
Madonna R, Geng YJ, Bolli R, Rokosh G, Ferdinandy P, Patterson C, De Caterina R. Co-activation of nuclear factor-κB and myocardin/serum response factor conveys the hypertrophy signal of high insulin levels in cardiac myoblasts. J Biol Chem 2014; 289:19585-98. [PMID: 24855642 DOI: 10.1074/jbc.m113.540559] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Hyperinsulinemia contributes to cardiac hypertrophy and heart failure in patients with the metabolic syndrome and type 2 diabetes. Here, high circulating levels of tumor necrosis factor (TNF)-α may synergize with insulin in signaling inflammation and cardiac hypertrophy. We tested whether high insulin affects activation of TNF-α-induced NF-κB and myocardin/serum response factor (SRF) to convey hypertrophy signaling in cardiac myoblasts. In canine cardiac myoblasts, treatment with high insulin (10(-8) to 10(-7) m) for 0-24 h increased insulin receptor substrate (IRS)-1 phosphorylation at Ser-307, decreased protein levels of chaperone-associated ubiquitin (Ub) E3 ligase C terminus of heat shock protein 70-interacting protein (CHIP), increased SRF activity, as well as β-myosin heavy chain (MHC) and myocardin expressions. Here siRNAs to myocardin or NF-κB, as well as CHIP overexpression prevented (while siRNA-mediated CHIP disruption potentiated) high insulin-induced SR element (SRE) activation and β-MHC expression. Insulin markedly potentiated TNF-α-induced NF-κB activation. Compared with insulin alone, insulin+TNF-α increased SRF/SRE binding and β-MHC expression, which was reversed by the NF-κB inhibitor pyrrolidine dithiocarbamate (PDTC) and by NF-κB silencing. In the hearts of db/db diabetic mice, in which Akt phosphorylation was decreased, p38MAPK, Akt1, and IRS-1 phosphorylation at Ser-307 were increased, together with myocardin expression as well as SRE and NF-κB activities. In response to high insulin, cardiac myoblasts increase the expression or the promyogenic transcription factors myocardin/SRF in a CHIP-dependent manner. Insulin potentiates TNF-α in inducing NF-κB and SRF/SRE activities. In hyperinsulinemic states, myocardin may act as a nuclear effector of insulin, promoting cardiac hypertrophy.
Collapse
Affiliation(s)
- Rosalinda Madonna
- From the Texas Heart Institute and University of Texas Medical School in Houston, Houston, Texas 77030, the Institute of Cardiology, and Center of Excellence on Aging, "G. d'Annunzio" University, 66100 Chieti, Italy
| | - Yong-Jian Geng
- From the Texas Heart Institute and University of Texas Medical School in Houston, Houston, Texas 77030
| | - Roberto Bolli
- the Institute of Molecular Cardiology, University of Louisville, Louisville, Kentucky 40202
| | - Gregg Rokosh
- the Institute of Molecular Cardiology, University of Louisville, Louisville, Kentucky 40202
| | - Peter Ferdinandy
- the Department of Pharmacology and Pharmacotherapy, Semmelweis University, H-1085 Budapest, Hungary, and
| | - Cam Patterson
- the Center for Molecular Cardiology, The University of Texas Medical Branch at Galveston, Galveston, Texas 77555
| | - Raffaele De Caterina
- the Institute of Cardiology, and Center of Excellence on Aging, "G. d'Annunzio" University, 66100 Chieti, Italy,
| |
Collapse
|
153
|
Condic ML. Totipotency: what it is and what it is not. Stem Cells Dev 2014; 23:796-812. [PMID: 24368070 PMCID: PMC3991987 DOI: 10.1089/scd.2013.0364] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2013] [Accepted: 12/23/2013] [Indexed: 02/03/2023] Open
Abstract
There is surprising confusion surrounding the concept of biological totipotency, both within the scientific community and in society at large. Increasingly, ethical objections to scientific research have both practical and political implications. Ethical controversy surrounding an area of research can have a chilling effect on investors and industry, which in turn slows the development of novel medical therapies. In this context, clarifying precisely what is meant by "totipotency" and how it is experimentally determined will both avoid unnecessary controversy and potentially reduce inappropriate barriers to research. Here, the concept of totipotency is discussed, and the confusions surrounding this term in the scientific and nonscientific literature are considered. A new term, "plenipotent," is proposed to resolve this confusion. The requirement for specific, oocyte-derived cytoplasm as a component of totipotency is outlined. Finally, the implications of twinning for our understanding of totipotency are discussed.
Collapse
Affiliation(s)
- Maureen L Condic
- Department of Neurobiology, School of Medicine, University of Utah , Salt Lake City, Utah
| |
Collapse
|
154
|
Acute mechanical overload increases IGF-I and MMP-9 mRNA in 3D tissue-engineered skeletal muscle. Biotechnol Lett 2014; 36:1113-24. [PMID: 24563297 DOI: 10.1007/s10529-014-1464-y] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2013] [Accepted: 01/09/2014] [Indexed: 01/24/2023]
Abstract
Skeletal muscle (SkM) is a tissue that responds to mechanical load following both physiological (exercise) or pathophysiological (bed rest) conditions. The heterogeneity of human samples and the experimental and ethical limitations of animal studies provide a rationale for the study of SkM plasticity in vitro. Many current in vitro approaches of mechanical loading of SkM disregard the three-dimensional (3D) structure in vivo. Tissue engineered 3D SkM, that displays highly aligned and differentiated myotubes, was used to investigate mechano-regulated gene transcription of genes implicated in hypertrophy/atrophy. Static loading (STL) and ramp loading (RPL) at 10 % strain for 60 min were used as mechano-stimulation with constructs sampled immediately for RNA extraction. STL increased IGF-I mRNA compared to both RPL and CON (control, p = 0.003 and 0.011 respectively) whilst MMP-9 mRNA increased in STL and RPL compared to CON (both p < 0.05). IGFBP-2 mRNA was differentially regulated in RPL and STL compared to CON (p = 0.057), whilst a reduction in IGFBP-5 mRNA was found for STL and RPL compared to CON (both p < 0.05). There was no effect in the expression of putative atrophic genes, myostatin, MuRF-1 and MAFBx (all p > 0.05). These data demonstrate a transcriptional signature associated with SkM hypertrophy within a tissue-engineered model that more greatly recapitulates the in vivo SkM structure compared previously published studies.
Collapse
|
155
|
Aloni-Grinstein R, Shetzer Y, Kaufman T, Rotter V. p53: the barrier to cancer stem cell formation. FEBS Lett 2014; 588:2580-9. [PMID: 24560790 DOI: 10.1016/j.febslet.2014.02.011] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2014] [Revised: 02/07/2014] [Accepted: 02/07/2014] [Indexed: 02/08/2023]
Abstract
The role of p53 as the "guardian of the genome" in differentiated somatic cells, triggering various biological processes, is well established. Recent studies in the stem cell field have highlighted a profound role of p53 in stem cell biology as well. These studies, combined with basic data obtained 20 years ago, provide insight into how p53 governs the quantity and quality of various stem cells, ensuring a sufficient repertoire of normal stem cells to enable proper development, tissue regeneration and a cancer free life. In this review we address the role of p53 in genomically stable embryonic stem cells, a unique predisposed cancer stem cell model and adult stem cells, its role in the generation of induced pluripotent stem cells, as well as its role as the barrier to cancer stem cell formation.
Collapse
Affiliation(s)
- Ronit Aloni-Grinstein
- Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Yoav Shetzer
- Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Tom Kaufman
- Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Varda Rotter
- Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot 76100, Israel.
| |
Collapse
|
156
|
Kelaini S, Cochrane A, Margariti A. Direct reprogramming of adult cells: avoiding the pluripotent state. STEM CELLS AND CLONING-ADVANCES AND APPLICATIONS 2014; 7:19-29. [PMID: 24627642 PMCID: PMC3931695 DOI: 10.2147/sccaa.s38006] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The procedure of using mature, fully differentiated cells and inducing them toward other cell types while bypassing an intermediate pluripotent state is termed direct reprogramming. Avoiding the pluripotent stage during cellular conversions can be achieved either through ectopic expression of lineage-specific factors (transdifferentiation) or a direct reprogramming process that involves partial reprogramming toward the pluripotent stage. Latest advances in the field seek to alleviate concerns that include teratoma formation or retroviral usage when it comes to delivering reprogramming factors to cells. They also seek to improve efficacy and efficiency of cellular conversion, both in vitro and in vivo. The final products of this reprogramming approach could be then directly implemented in regenerative and personalized medicine.
Collapse
Affiliation(s)
- Sophia Kelaini
- Centre for Experimental Medicine, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Institute of Clinical Sciences, Belfast, UK
| | - Amy Cochrane
- Centre for Experimental Medicine, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Institute of Clinical Sciences, Belfast, UK
| | - Andriana Margariti
- Centre for Experimental Medicine, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Institute of Clinical Sciences, Belfast, UK
| |
Collapse
|
157
|
Batista LFZ. Telomere biology in stem cells and reprogramming. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2014; 125:67-88. [PMID: 24993698 DOI: 10.1016/b978-0-12-397898-1.00003-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Telomerase expression in humans is restricted to different populations of stem and progenitor cells, being silenced in most somatic tissues. Efficient telomere homeostasis is essential for embryonic and adult stem cell function and therefore essential for tissue homeostasis throughout organismal life. Accordingly, the mutations in telomerase culminate in reduced stem cell function both in vivo and in vitro and have been associated with tissue dysfunction in human patients. Despite the importance of telomerase for stem cell biology, the mechanisms behind telomerase regulation during development are still poorly understood, mostly due to difficulties in acquiring and maintaining pluripotent stem cell populations in culture. In this chapter, we will analyze recent developments in this field, including the importance of efficient telomere homeostasis in different stem cell types and the role of telomerase in different techniques used for cellular reprogramming.
Collapse
Affiliation(s)
- Luis F Z Batista
- Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, USA; Department of Developmental Biology, Washington University School of Medicine, St. Louis, Missouri, USA
| |
Collapse
|
158
|
Donati C, Cencetti F, Bruni P. Sphingosine 1-phosphate axis: a new leader actor in skeletal muscle biology. Front Physiol 2013; 4:338. [PMID: 24324439 PMCID: PMC3839259 DOI: 10.3389/fphys.2013.00338] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2013] [Accepted: 11/01/2013] [Indexed: 12/23/2022] Open
Abstract
Sphingosine 1-phosphate (S1P) is a bioactive lipid involved in the regulation of biological processes such as proliferation, differentiation, motility, and survival. Here we review the role of S1P in the biology and homeostasis of skeletal muscle. S1P derives from the catabolism of sphingomyelin and is produced by sphingosine phosphorylation catalyzed by sphingosine kinase (SK). S1P can act either intracellularly or extracellularly through specific ligation to its five G protein-coupled receptors (GPCR) named S1P receptors (S1PR). Many experimental findings obtained in the last 20 years demonstrate that S1P and its metabolism play a multifaceted role in the regulation of skeletal muscle regeneration. Indeed, this lipid is known to activate muscle-resident satellite cells, regulating their proliferation and differentiation, as well as mesenchymal progenitors such as mesoangioblasts that originate outside skeletal muscle, both involved in tissue repair following an injury or disease. The molecular mechanism of action of S1P in skeletal muscle cell precursors is highly complex, especially because S1P axis is under the control of a number of growth factors and cytokines, canonical regulators of skeletal muscle biology. Moreover, this lipid is crucially involved in the regulation of skeletal muscle contractile properties, responsiveness to insulin, fatigue resistance and tropism. Overall, on the basis of these findings S1P signaling appears to be an appealing pharmacological target for improving skeletal muscle repair. Nevertheless, further understanding is required on the regulation of S1P downstream signaling pathways and the expression of S1PR. This article will resume our current knowledge on S1P signaling in skeletal muscle, hopefully stimulating further investigation in the field, aimed at individuating novel molecular targets for ameliorating skeletal muscle regeneration and reducing fibrosis of the tissue after a trauma or due to skeletal muscle diseases.
Collapse
Affiliation(s)
- Chiara Donati
- Dipartimento di Scienze Biomediche, Sperimentali e Cliniche, University of Florence Florence, Italy ; Istituto Interuniversitario di Miologia Italy
| | | | | |
Collapse
|
159
|
Abstract
The nucleus is the distinguishing feature of eukaryotic cells. Until recently, it was often considered simply as a unique compartment containing the genetic information of the cell and associated machinery, without much attention to its structure and mechanical properties. This article provides compelling examples that illustrate how specific nuclear structures are associated with important cellular functions, and how defects in nuclear mechanics can cause a multitude of human diseases. During differentiation, embryonic stem cells modify their nuclear envelope composition and chromatin structure, resulting in stiffer nuclei that reflect decreased transcriptional plasticity. In contrast, neutrophils have evolved characteristic lobulated nuclei that increase their physical plasticity, enabling passage through narrow tissue spaces in their response to inflammation. Research on diverse cell types further demonstrates how induced nuclear deformations during cellular compression or stretch can modulate cellular function. Pathological examples of disturbed nuclear mechanics include the many diseases caused by mutations in the nuclear envelope proteins lamin A/C and associated proteins, as well as cancer cells that are often characterized by abnormal nuclear morphology. In this article, we will focus on determining the functional relationship between nuclear mechanics and cellular (dys-)function, describing the molecular changes associated with physiological and pathological examples, the resulting defects in nuclear mechanics, and the effects on cellular function. New insights into the close relationship between nuclear mechanics and cellular organization and function will yield a better understanding of normal biology and will offer new clues into therapeutic approaches to the various diseases associated with defective nuclear mechanics.
Collapse
Affiliation(s)
- Jan Lammerding
- Brigham and Women's Hospital/Harvard Medical School, Cambridge, Massachusetts, USA.
| |
Collapse
|
160
|
Abstract
Heart disease affects millions worldwide and is a progressive condition involving loss of cardiomyocytes. The human heart has limited endogenous regenerative capacity and is thus an important target for novel regenerative medicine approaches. Although cell-based regenerative therapies hold promise, cellular reprogramming of endogenous cardiac fibroblasts, which represent more than half of the cells in the mammalian heart, may be an attractive alternative strategy for regenerating cardiac muscle. Recent advances leveraging years of developmental biology point to the feasibility of generating de novo cardiomyocyte-like cells from terminally differentiated nonmyocytes in the heart in situ after ischemic damage. Here, we review the progress in cardiac reprogramming methods and consider the opportunities and challenges that lie ahead in refining this technology for regenerative medicine.
Collapse
Affiliation(s)
- Li Qian
- From the McAllister Heart Institute, Department of Pathology and Laboratory Medicine, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill
| | | |
Collapse
|
161
|
Deane CS, Hughes DC, Sculthorpe N, Lewis MP, Stewart CE, Sharples AP. Impaired hypertrophy in myoblasts is improved with testosterone administration. J Steroid Biochem Mol Biol 2013; 138:152-61. [PMID: 23714396 DOI: 10.1016/j.jsbmb.2013.05.005] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/21/2013] [Revised: 05/08/2013] [Accepted: 05/14/2013] [Indexed: 11/24/2022]
Abstract
We investigated the ability of testosterone (T) to restore differentiation in multiple population doubled (PD) murine myoblasts, previously shown to have a reduced differentiation in monolayer and bioengineered skeletal muscle cultures vs. their parental controls (CON) (Sharples et al., 2011, 2012 [7,26]). Cells were exposed to low serum conditions in the presence or absence of T (100nM)±PI3K inhibitor (LY294002) for 72h and 7 days (early and late muscle differentiation respectively). Morphological analyses were performed to determine myotube number, diameter (μm) and myonuclear accretion as indices of differentiation and myotube hypertrophy. Changes in gene expression for myogenin, mTOR and myostatin were also performed. Myotube diameter in CON and PD cells increased from 17.32±2.56μm to 21.02±1.89μm and 14.58±2.66μm to 18.29±3.08μm (P≤0.05) respectively after 72h of T exposure. The increase was comparable in both PD (+25%) and CON cells (+21%) suggesting a similar intrinsic ability to respond to exogenous T administration. T treatment also significantly increased myonuclear accretion (% of myotubes expressing 5+ nuclei) in both cell types after 7 days exposure (P≤0.05). Addition of PI3K inhibitor (LY294002) in the presence of T attenuated these effects in myotube morphology (in both cell types) suggesting a role for the PI3K pathway in T stimulated hypertrophy. Finally, PD myoblasts showed reduced responsiveness to T stimulated mRNA expression of mTOR vs. CON cells and T also reduced myostatin expression in PD myoblasts only. The present study demonstrates testosterone administration improves hypertrophy in myoblasts that basally display impaired differentiation and hypertrophic capacity vs. their parental controls, the action of testosterone in this model was mediated by PI3K/Akt pathway.
Collapse
Affiliation(s)
- Colleen S Deane
- Muscle Cellular and Molecular Physiology Research Group (MCMPRG), Institute of Sport and Physical Activity Research (ISPAR), University of Bedfordshire, UK; School of Health and Social Care, Bournemouth University, UK
| | | | | | | | | | | |
Collapse
|
162
|
Pandurangan M, Moorthy H, Sambandam R, Jeyaraman V, Irisappan G, Kothandam R. Effects of stress hormone cortisol on the mRNA expression of myogenenin, MyoD, Myf5, PAX3 and PAX7. Cytotechnology 2013; 66:839-44. [PMID: 24113918 DOI: 10.1007/s10616-013-9635-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2013] [Accepted: 08/17/2013] [Indexed: 10/26/2022] Open
Abstract
The present investigation was carried out to evaluate the effect of stress hormone cortisol on the myogenic markers in the C2C12 cells co-cultured with 3T3-L1 preadipocytes. Co-culturing was achieved by transwell inserts with a 0.4 μm porous membrane. C2C12 and 3T3-L1 cells were grown independently on the transwell plates. After differentiation, inserts containing 3T3-L1 cells were transferred to C2C12 plates for co-culturing. 10 μg/μl of cortisol was added to the medium. After 72 h of treatment, C2C12 cells which were in the lower well were harvested for analysis. RT-PCR analysis of myogenic markers such as of myogenin, MyoD, Myf5, PAX3 and PAX7 showed a significant reduction in the mRNA expression of these myogenic markers. In addition, cortisol increased calpain activity, which led to accelerated protein degradation, which in turn reduced the myogenic rate. In conclusion, cortisol treatment reduced mRNA expression of myogenic markers in the co-cultured C2C12 cells, which is quite distinct from one dimensional mono-cultured C2C12 cells.
Collapse
Affiliation(s)
- Muthuraman Pandurangan
- Department of Food Science and Nutrition, Catholic University of Daegu, Daegu, South Korea,
| | | | | | | | | | | |
Collapse
|
163
|
Luna-Zurita L, Bruneau BG. Chromatin modulators as facilitating factors in cellular reprogramming. Curr Opin Genet Dev 2013; 23:556-61. [PMID: 23993229 DOI: 10.1016/j.gde.2013.07.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2013] [Revised: 07/10/2013] [Accepted: 07/15/2013] [Indexed: 10/26/2022]
Abstract
In the last few years, cellular reprogramming has emerged as a means to alter cellular identity and generate diverse cell types for disease modeling, drug testing, and potential therapeutic use. Since each cell type is a result of a specific gene expression profile finely regulated by the activity of a repertoire of transcription factors (TFs), reprogramming approaches have, thus far, been relatively inefficient and based largely on the forced expression of selective cell type-specific TFs. TFs function within the confines of chromatin, and the chromatin states can in turn be modulated by TF activity. Therefore, the knowledge of how chromatin remodeling factors alter chromatin structure, control TF activity and gene expression has led to an improved reprogramming efficiency and extended the number of cellular types that can be generated by cellular reprogramming. Here we review recent insights into the role and mechanisms by which chromatin remodeling, histone modifications, and DNA methylation contribute to cellular differentiation and reprogramming.
Collapse
Affiliation(s)
- Luis Luna-Zurita
- Gladstone Institute of Cardiovascular Disease, San Francisco, CA 94158, USA
| | | |
Collapse
|
164
|
Durcan PJ, Al-Shanti N, Stewart CE. Identification and characterization of novel Kirrel isoform during myogenesis. Physiol Rep 2013; 1:e00044. [PMID: 24303129 PMCID: PMC3835000 DOI: 10.1002/phy2.44] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2013] [Accepted: 07/03/2013] [Indexed: 12/31/2022] Open
Abstract
Somatic cell fusion is an essential component of skeletal muscle development and growth and repair from injury. Additional cell types such as trophoblasts and osteoclasts also require somatic cell fusion events to perform their physiological functions. Currently we have rudimentary knowledge on molecular mechanisms regulating somatic cell fusion events in mammals. We therefore investigated during in vitro murine myogenesis a mammalian homolog, Kirrel, of the Drosophila Melanogaster genes Roughest (Rst) and Kin of Irre (Kirre) which regulate somatic muscle cell fusion during embryonic development. Our results demonstrate the presence of a novel murine Kirrel isoform containing a truncated cytoplasmic domain which we term Kirrel B. Protein expression levels of Kirrel B are inverse to the occurrence of cell fusion events during in vitro myogenesis which is in stark contrast to the expression profile of Rst and Kirre during myogenesis in Drosophila. Furthermore, chemical inhibition of cell fusion confirmed the inverse expression pattern of Kirrel B protein levels in relation to cell fusion events. The discovery of a novel Kirrel B protein isoform during myogenesis highlights the need for more thorough investigation of the similarities and potential differences between fly and mammals with regards to the muscle cell fusion process.
Collapse
Affiliation(s)
- Peter J Durcan
- Department of Physiological Sciences, Stellenbosch University Merriman avenue, Stellenbosch, 7600, Western Cape, South Africa ; Institute for Biomedical Research into Human movement, School of Healthcare Science, Manchester Metropolitan University Oxford road, M1 5GD, Manchester, U.K
| | | | | |
Collapse
|
165
|
Marques L, Thorsteinsdóttir S. Dynamics of Akt activation during mouse embryo development: distinct subcellular patterns distinguish proliferating versus differentiating cells. Differentiation 2013; 86:48-56. [PMID: 23968884 DOI: 10.1016/j.diff.2013.07.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2012] [Revised: 06/21/2013] [Accepted: 07/03/2013] [Indexed: 12/19/2022]
Abstract
Akt is a highly conserved serine-threonine protein kinase which has been implicated in a wide variety of cellular functions, from the regulation of growth and metabolism, to activation of pro-survival pathways and cell proliferation, and promotion of differentiation in specific cell types. However, very little is known about the spatial and temporal pattern of Akt activity within cells and whether this pattern changes as cells enter and proceed in their differentiation programs. To address this issue we profiled Akt activation in E8.5-E13.5 mouse embryos and in C2C12 cells. We used a commercial antibody against Akt, phosphorylated on one of its activating residues, Thr-308, and performed high resolution confocal imaging of the immunofluorescence in labeled embryos. We observe strong Akt activity during mitosis in the dermomyotome, the neuroepithelium and some mesenchymal cells. This burst of activity fills the whole cell except for heterochromatin-positive areas in the nucleus. A surge in activity during mitosis is also observed in subconfluent C2C12 cells. Later on in the differentiation programs of skeletal muscle and neural cells, derivatives of the dermomyotome and neuroepithelium, respectively, we find robust, sustained Akt activity in the cytoplasm, but not in the nucleus. Concomitantly with skeletal muscle differentiation, Akt activity becomes concentrated in the sarcomeric Z-disks whereas developing neurons maintain a uniform cytoplasmic pattern of activated Akt. Our findings reveal unprecedented cellular and subcellular details of Akt activity during mouse embryo development, which is spatially and temporally consistent with proposed functions for Akt in mitosis and myogenic and neural differentiation and/or survival. Our results thus demonstrate a subcellular change in the pattern of Akt activation when skeletal muscle and neural progenitor cells cease dividing and progress in their differentiation programs.
Collapse
Affiliation(s)
- Luís Marques
- Centro de Biologia Ambiental/Departamento de Biologia Animal, Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal; Instituto Gulbenkian de Ciência, Oeiras, Portugal.
| | | |
Collapse
|
166
|
Alignment of muscle precursor cells on the vertical edges of thick carbon nanotube films. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2013; 33:4274-9. [PMID: 23910343 DOI: 10.1016/j.msec.2013.06.017] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2012] [Revised: 05/17/2013] [Accepted: 06/18/2013] [Indexed: 01/09/2023]
Abstract
The development of scaffolds and templates is an essential aspect of tissue engineering. We show that thick (>0.5 mm) vertically aligned carbon nanotube films, made by chemical vapour deposition, can be used as biocompatible substrates for the directional alignment of mouse muscle cells where the cells grow on the exposed sides of the films. Ultra high resolution scanning electron microscopy reveals that the films themselves consist mostly of small diameter (10 nm) multi-wall carbon nanotubes of wavy morphology with some single wall carbon nanotubes. Our findings show that for this alignment to occur the nanotubes must be in pristine condition. Mechanical wiping of the films to create directional alignment is detrimental to directional bioactivity. Larger areas for study have been formed from a composite of multiply stacked narrow strips of nanotubes wipe-transferred onto elastomer supports. These composite substrates appear to show a useful degree of alignment of the cells.
Collapse
|
167
|
Wnt/β-catenin signaling triggers neuron reprogramming and regeneration in the mouse retina. Cell Rep 2013; 4:271-86. [PMID: 23850287 DOI: 10.1016/j.celrep.2013.06.015] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2012] [Revised: 03/01/2013] [Accepted: 06/11/2013] [Indexed: 12/11/2022] Open
Abstract
Cell-fusion-mediated somatic-cell reprogramming can be induced in culture; however, whether this process occurs in mammalian tissues remains enigmatic. Here, we show that upon activation of Wnt/β-catenin signaling, mouse retinal neurons can be transiently reprogrammed in vivo back to a precursor stage. This occurs after their spontaneous fusion with transplanted hematopoietic stem and progenitor cells (HSPCs). Moreover, we demonstrate that retinal damage is essential for cell-hybrid formation in vivo. Newly formed hybrids can proliferate, commit to differentiation toward a neuroectodermal lineage, and finally develop into terminally differentiated neurons. This results in partial regeneration of the damaged retinal tissue, with functional rescue. Following retinal damage and induction of Wnt/β-catenin signaling, cell-fusion-mediated reprogramming also occurs after endogenous recruitment of bone-marrow-derived cells in the eyes. Our data demonstrate that in vivo reprogramming of terminally differentiated retinal neurons after their fusion with HSPCs is a potential mechanism for tissue regeneration.
Collapse
|
168
|
Mohamed JS, Lopez MA, Cox GA, Boriek AM. Ankyrin repeat domain protein 2 and inhibitor of DNA binding 3 cooperatively inhibit myoblast differentiation by physical interaction. J Biol Chem 2013; 288:24560-8. [PMID: 23824195 DOI: 10.1074/jbc.m112.434423] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Ankyrin repeat domain protein 2 (ANKRD2) translocates from the nucleus to the cytoplasm upon myogenic induction. Overexpression of ANKRD2 inhibits C2C12 myoblast differentiation. However, the mechanism by which ANKRD2 inhibits myoblast differentiation is unknown. We demonstrate that the primary myoblasts of mdm (muscular dystrophy with myositis) mice (pMB(mdm)) overexpress ANKRD2 and ID3 (inhibitor of DNA binding 3) proteins and are unable to differentiate into myotubes upon myogenic induction. Although suppression of either ANKRD2 or ID3 induces myoblast differentiation in mdm mice, overexpression of ANKRD2 and inhibition of ID3 or vice versa is insufficient to inhibit myoblast differentiation in WT mice. We identified that ANKRD2 and ID3 cooperatively inhibit myoblast differentiation by physical interaction. Interestingly, although MyoD activates the Ankrd2 promoter in the skeletal muscles of wild-type mice, SREBP-1 (sterol regulatory element binding protein-1) activates the same promoter in the skeletal muscles of mdm mice, suggesting the differential regulation of Ankrd2. Overall, we uncovered a novel pathway in which SREBP-1/ANKRD2/ID3 activation inhibits myoblast differentiation, and we propose that this pathway acts as a critical determinant of the skeletal muscle developmental program.
Collapse
Affiliation(s)
- Junaith S Mohamed
- Section of Pulmonary, Critical Care, and Sleep Medicine, Department of Medicine, Baylor College of Medicine, Houston, Texas 77030, USA
| | | | | | | |
Collapse
|
169
|
Addis RC, Epstein JA. Induced regeneration--the progress and promise of direct reprogramming for heart repair. Nat Med 2013; 19:829-36. [PMID: 23836233 PMCID: PMC3862032 DOI: 10.1038/nm.3225] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2013] [Accepted: 05/08/2013] [Indexed: 12/20/2022]
Abstract
Regeneration of cardiac tissue has the potential to transform cardiovascular medicine. Recent advances in stem cell biology and direct reprogramming, or transdifferentiation, have produced powerful new tools to advance this goal. In this Review we examine key developments in the generation of new cardiomyocytes in vitro as well as the exciting progress that has been made toward in vivo reprogramming of cardiac tissue. We also address controversies and hurdles that challenge the field.
Collapse
Affiliation(s)
- Russell C Addis
- Department of Cell and Developmental Biology, Institute for Regenerative Medicine and Cardiovascular Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA.
| | | |
Collapse
|
170
|
Faiz M, Nagy A. Induced Pluripotent Stem Cells and Disorders of the Nervous System: Progress, Problems, and Prospects. Neuroscientist 2013; 19:567-577. [PMID: 23797497 DOI: 10.1177/1073858413493148] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Advances in cellular reprograming have shown that the delivery of specific transcription factors can result in the shift of one cell type to another. Brief forced expression of the four Yamanaka reprogramming factors (Klf4, Sox2, c-Myc, and Oct4) is able to convert many cell types into induced pluripotent stem cells, whereas some lineage specific transcription factors can convert cells from one type directly to another. Numerous strategies have already been developed for deriving neural cell types, with the hopes of better understanding/alleviating neurodegenerative disease. These cells facilitate drug discovery and constitute an autologous source of cells for brain repair, thus, avoiding rejection issues faced by allografts derived from embryonic stem cells. However, proper characterization of the various types of reprogrammed cells and an understanding of how these cells acquire neural fate is necessary before their translation into the clinic. Here, we review the progress, problems, and prospects with reprogrammed cell types with regards to neurodegenerative disease.
Collapse
Affiliation(s)
- Maryam Faiz
- 1Mount Sinai Hospital, Samuel Lunenfeld Research Institute, Toronto, Ontario, Canada
| | | |
Collapse
|
171
|
Sharples AP, Al-Shanti N, Hughes DC, Lewis MP, Stewart CE. The role of insulin-like-growth factor binding protein 2 (IGFBP2) and phosphatase and tensin homologue (PTEN) in the regulation of myoblast differentiation and hypertrophy. Growth Horm IGF Res 2013; 23:53-61. [PMID: 23583027 DOI: 10.1016/j.ghir.2013.03.004] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2012] [Revised: 01/30/2013] [Accepted: 03/13/2013] [Indexed: 11/22/2022]
Abstract
The complex actions of the insulin-like-growth factor binding proteins (IGFBPs) in skeletal muscle are becoming apparent, with IGFBP2 being implicated in skeletal muscle cell proliferation and differentiation (Ernst et al., 1992; Sharples et al., 2010). Furthermore, PTEN signalling has been linked to IGFBP2 action in other cell types by co-ordinating downstream Akt signalling, a known modulator of myoblast differentiation. The present study therefore aimed to determine the interaction between IGFBP2 and PTEN on myoblast differentiation. It has previously been established that C2C12 cells have high IGFBP2 gene expression upon transfer to low serum media, and that expression reduces rapidly as cells differentiate over 72 h [1]. Wishing to establish a potential role for IGFBP2 in this model, a neutralising IGFBP2 antibody was administered to C2C12 myoblasts upon initiation of differentiation. Myoblasts subsequently displayed reduced morphological differentiation (myotube number), biochemical differentiation (creatine kinase) and myotube hypertrophy (myotube area) with an early reduction in Akt phosphorylation. Knock-down of phosphatase and tensin homologue (PTEN) using siRNA in the absence of the neutralising antibody did not improve differentiation or hypertrophy vs. control conditions, however, in the presence of the neutralising IGFBP2 antibody, differentiation was restored and importantly hypertrophy exceeded that of control levels. Overall, these data suggest that; 1) reduced early availability of IGFBP2 can inhibit myoblast differentiation at later time points, 2) knock-down of PTEN levels can restore myoblast differentiation in the presence of neutralising IGFBP2 antibody, and 3) PTEN inhibition acts as a potent inducer of myotube hypertrophy when the availability of IGFBP2 is reduced in C2C12 myoblasts.
Collapse
Affiliation(s)
- Adam P Sharples
- Stem Cell, Ageing and Molecular Physiology (SCAMP) Unit, Research Institute for Sport and Exercise Sciences (RISES), School of Sport and Exercise Sciences, Liverpool John Moores University, Tom Reilly Building, Byrom Street, Liverpool, UK.
| | | | | | | | | |
Collapse
|
172
|
Weyers JJ, Schwartz SM, Minami E, Carlson DD, Dupras SK, Weitz K, Simons M, Cox TC, Murry CE, Mahoney WM. Effects of cell grafting on coronary remodeling after myocardial infarction. J Am Heart Assoc 2013; 2:e000202. [PMID: 23723253 PMCID: PMC3698786 DOI: 10.1161/jaha.113.000202] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
BACKGROUND With recent advances in therapeutic applications of stem cells, cell engraftment has become a promising therapy for replacing injured myocardium after infarction. The survival and function of injected cells, however, will depend on the efficient vascularization of the new tissue. Here we describe the arteriogenic remodeling of the coronary vessels that supports vascularization of engrafted tissue postmyocardial infarction (post-MI). METHODS AND RESULTS Following MI, murine hearts were injected with a skeletal myoblast cell line previously shown to develop into large grafts. Microcomputed tomography at 28 days postengraftment revealed the 3-dimensional structure of the newly formed conducting vessels. The grafts elicited both an angiogenic response and arteriogenic remodeling of the coronary arteries to perfuse the graft. The coronaries upstream of the graft also remodeled, showing an increase in branching, and a decrease in vascular density. Histological analysis revealed the presence of capillaries as well as larger vascular lumens within the graft. Some graft vessels were encoated by smooth muscle α-actin positive cells, implying that vascular remodeling occurs at both the conducting arterial and microvascular levels. CONCLUSIONS Following MI and skeletal myoblast engraftment, the murine coronary vessels exhibit plasticity that enables both arteriogenic remodeling of the preexisting small branches of the coronary arteries and development of large and small smooth muscle encoated vessels within the graft. Understanding the molecular mechanisms underlying these 2 processes suggests mechanisms to enhance the therapeutic vascularization in patients with myocardial ischemia.
Collapse
Affiliation(s)
- Jill J Weyers
- Department of Pathology, Center for Cardiovascular Biology and Institute for Stem Cell and Regenerative Medicine, University of Washington, Seattle, WA 98109, USA
| | | | | | | | | | | | | | | | | | | |
Collapse
|
173
|
Chatterjee S, Nam D, Guo B, Kim JM, Winnier GE, Lee J, Berdeaux R, Yechoor VK, Ma K. Brain and muscle Arnt-like 1 is a key regulator of myogenesis. J Cell Sci 2013; 126:2213-24. [PMID: 23525013 PMCID: PMC3672937 DOI: 10.1242/jcs.120519] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/28/2013] [Indexed: 12/28/2022] Open
Abstract
The circadian clock network is an evolutionarily conserved mechanism that imparts temporal regulation to diverse biological processes. Brain and muscle Arnt-like 1 (Bmal1), an essential transcriptional activator of the clock, is highly expressed in skeletal muscle. However, whether this key clock component impacts myogenesis, a temporally regulated event that requires the sequential activation of myogenic regulatory factors, is not known. Here we report a novel function of Bmal1 in controlling myogenic differentiation through direct transcriptional activation of components of the canonical Wnt signaling cascade, a major inductive signal for embryonic and postnatal muscle growth. Genetic loss of Bmal1 in mice leads to reduced total muscle mass and Bmal1-deficient primary myoblasts exhibit significantly impaired myogenic differentiation accompanied by markedly blunted expression of key myogenic regulatory factors. Conversely, forced expression of Bmal1 enhances differentiation of C2C12 myoblasts. This cell-autonomous effect of Bmal1 is mediated by Wnt signaling as both expression and activity of Wnt components are markedly attenuated by inhibition of Bmal1, and activation of the Wnt pathway partially rescues the myogenic defect in Bmal1-deficient myoblasts. We further reveal direct association of Bmal1 with promoters of canonical Wnt pathway genes, and as a result of this transcriptional regulation, Wnt signaling components exhibit intrinsic circadian oscillation. Collectively, our study demonstrates that the core clock gene, Bmal1, is a positive regulator of myogenesis, which may represent a temporal regulatory mechanism to fine-tune myocyte differentiation.
Collapse
Affiliation(s)
- Somik Chatterjee
- Center for Diabetes Research, Department of Medicine, The Methodist Hospital Research Institute, Houston, TX, 77030, USA
| | - Deokhwa Nam
- Center for Diabetes Research, Department of Medicine, The Methodist Hospital Research Institute, Houston, TX, 77030, USA
| | - Bingyan Guo
- Center for Diabetes Research, Department of Medicine, The Methodist Hospital Research Institute, Houston, TX, 77030, USA
- Department of Cardiovascular Medicine, Second Affiliated Hospital, Hebei Medical University, Shijiazhuang, 050017, Hebei, China
| | - Ji M. Kim
- Center for Diabetes Research, Department of Medicine, The Methodist Hospital Research Institute, Houston, TX, 77030, USA
| | - Glen E. Winnier
- Center for Diabetes Research, Department of Medicine, The Methodist Hospital Research Institute, Houston, TX, 77030, USA
| | - Jeongkyung Lee
- Diabetes and Endocrinology Research Center, Department of Medicine, Baylor College of Medicine, Houston, TX, USA
| | - Rebecca Berdeaux
- Department of Integrative Biology and Pharmacology, University of Texas Health Science Center at Houston, Houston, TX, USA
| | - Vijay K. Yechoor
- Diabetes and Endocrinology Research Center, Department of Medicine, Baylor College of Medicine, Houston, TX, USA
| | - Ke Ma
- Center for Diabetes Research, Department of Medicine, The Methodist Hospital Research Institute, Houston, TX, 77030, USA
| |
Collapse
|
174
|
Intrinsic and extrinsic connections of Tet3 dioxygenase with CXXC zinc finger modules. PLoS One 2013; 8:e62755. [PMID: 23690950 PMCID: PMC3653909 DOI: 10.1371/journal.pone.0062755] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2012] [Accepted: 03/25/2013] [Indexed: 12/16/2022] Open
Abstract
Tet proteins are emerging as major epigenetic modulators of cell fate and plasticity. However, little is known about how Tet proteins are targeted to selected genomic loci in distinct biological contexts. Previously, a CXXC-type zinc finger domain in Tet1 was shown to bind CpG-rich DNA sequences. Interestingly, in human and mouse the Tet2 and Tet3 genes are adjacent to Cxxc4 and Cxxc10-1, respectively. The CXXC domains encoded by these loci, together with those in Tet1 and Cxxc5, identify a distinct homology group within the CXXC domain family. Here we provide evidence for alternative mouse Tet3 transcripts including the Cxxc10-1 sequence (Tet3CXXC) and for an interaction between Tet3 and Cxxc4. In vitro Cxxc4 and the isolated CXXC domains of Tet1 and Tet3CXXC bind DNA substrates with similar preference towards the modification state of cytosine at a single CpG site. In vivo Tet1 and Tet3 isoforms with and without CXXC domain hydroxylate genomic 5-methylcytosine with similar activity. Relative transcript levels suggest that distinct ratios of Tet3CXXC isoforms and Tet3-Cxxc4 complex may be present in adult tissues. Our data suggest that variable association with CXXC modules may contribute to context specific functions of Tet proteins.
Collapse
|
175
|
Mukhopadhyay A. Perspective on liver regeneration by bone marrow-derived stem cells-a scientific realization or a paradox. Cytotherapy 2013; 15:881-92. [PMID: 23623692 DOI: 10.1016/j.jcyt.2013.02.013] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2012] [Revised: 12/27/2012] [Accepted: 02/09/2013] [Indexed: 12/11/2022]
Abstract
Bone marrow (BM)-derived stem cells are reported to have cellular plasticity, which provoked many investigators to use of these cells in the regeneration of nonhematopoietic tissues. However, adult stem cell plasticity contradicts our classic understanding on progressive restriction of the developmental potential of a cell type. Many alternate mechanisms have been proposed to explain this phenomenon; the working hypotheses for elucidating the cellular plasticity of BM-derived stem cells are on the basis of direct differentiation and/or fusion between donor and recipient cells. This review dissects the different outcomes of the investigations on liver regeneration, which were performed with the use of BM-derived stem cells in experimental animals, and reveals some critical factors to explain cellular plasticity. It has been hypothesized that the competent BM-derived stem/progenitor cells, under the influence of liver-regenerating cues, can directly differentiate into hepatic cells. This differentiation takes place as a result of genetic reprogramming, which may be possible in the chemically induced acute liver injury model or at the stage of fetal liver development. Cellular plasticity emerges as an important phenomenon in cell-based therapies for the treatment of many liver diseases in which tissue regeneration is necessary.
Collapse
Affiliation(s)
- Asok Mukhopadhyay
- Stem Cell Biology & Center for Molecular Medicine, National Institute of Immunology, Aruna Asaf Ali Marg, New Delhi, India.
| |
Collapse
|
176
|
Efficient and reproducible myogenic differentiation from human iPS cells: prospects for modeling Miyoshi Myopathy in vitro. PLoS One 2013; 8:e61540. [PMID: 23626698 PMCID: PMC3633995 DOI: 10.1371/journal.pone.0061540] [Citation(s) in RCA: 153] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2012] [Accepted: 03/11/2013] [Indexed: 12/12/2022] Open
Abstract
The establishment of human induced pluripotent stem cells (hiPSCs) has enabled the production of in vitro, patient-specific cell models of human disease. In vitro recreation of disease pathology from patient-derived hiPSCs depends on efficient differentiation protocols producing relevant adult cell types. However, myogenic differentiation of hiPSCs has faced obstacles, namely, low efficiency and/or poor reproducibility. Here, we report the rapid, efficient, and reproducible differentiation of hiPSCs into mature myocytes. We demonstrated that inducible expression of myogenic differentiation1 (MYOD1) in immature hiPSCs for at least 5 days drives cells along the myogenic lineage, with efficiencies reaching 70–90%. Myogenic differentiation driven by MYOD1 occurred even in immature, almost completely undifferentiated hiPSCs, without mesodermal transition. Myocytes induced in this manner reach maturity within 2 weeks of differentiation as assessed by marker gene expression and functional properties, including in vitro and in vivo cell fusion and twitching in response to electrical stimulation. Miyoshi Myopathy (MM) is a congenital distal myopathy caused by defective muscle membrane repair due to mutations in DYSFERLIN. Using our induced differentiation technique, we successfully recreated the pathological condition of MM in vitro, demonstrating defective membrane repair in hiPSC-derived myotubes from an MM patient and phenotypic rescue by expression of full-length DYSFERLIN (DYSF). These findings not only facilitate the pathological investigation of MM, but could potentially be applied in modeling of other human muscular diseases by using patient-derived hiPSCs.
Collapse
|
177
|
Halley-Stott RP, Gurdon JB. Epigenetic memory in the context of nuclear reprogramming and cancer. Brief Funct Genomics 2013; 12:164-73. [PMID: 23585580 PMCID: PMC3662891 DOI: 10.1093/bfgp/elt011] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Epigenetic memory represents a natural mechanism whereby the identity of a cell is maintained through successive cell cycles, allowing the specification and maintenance of differentiation during development and in adult cells. Cancer is a loss or reversal of the stable differentiated state of adult cells and may be mediated in part by epigenetic changes. The identity of somatic cells can also be reversed experimentally by nuclear reprogramming. Nuclear reprogramming experiments reveal the mechanisms required to activate embryonic gene expression in adult cells and thus provide insight into the reversal of epigenetic memory. In this article, we will introduce epigenetic memory and the mechanisms by which it may operate. We limit our discussion primarily to the context of nuclear reprogramming and briefly discuss the relevance of memory and reprogramming to cancer biology.
Collapse
Affiliation(s)
- Richard P Halley-Stott
- The Wellcome Trust/Cancer Research UK Gurdon Institute, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QN United Kingdom
| | | |
Collapse
|
178
|
Lluis F, Cosma MP. Resetting epigenetic signatures to induce somatic cell reprogramming. Cell Mol Life Sci 2013; 70:1413-24. [PMID: 22932957 PMCID: PMC11113704 DOI: 10.1007/s00018-012-1137-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2012] [Revised: 08/07/2012] [Accepted: 08/13/2012] [Indexed: 10/27/2022]
Abstract
Somatic cell reprogramming consists of the induction of a complex sequence of events that results in the modification of the developmental state of the cell. It is now routinely possible to reprogram fully differentiated cells back to pluripotent cells, and to transdifferentiate cells of a given type in cells of a totally different lineage origin. However, whether there are key initiating factors that are distinct from those that control stem-cell renewal and that can initiate the reprogramming process remains unknown. In contrast, what is clear is that, by modifying the epigenetic status of a cell, its reprogramming can be initiated. Here, we review the current literature that shows how the plasticity of a cell can be modulated by modifying its epigenetic status, and we discuss how epigenetic barriers can be removed, to induce an efficient reprogramming process.
Collapse
Affiliation(s)
- Frederic Lluis
- Centre for Genomic Regulation (CRG) and UPF, Dr. Aiguader, 88, 08003 Barcelona, Spain
| | - Maria Pia Cosma
- Centre for Genomic Regulation (CRG) and UPF, Dr. Aiguader, 88, 08003 Barcelona, Spain
- Institució Catalana de Recerca i Estudis Avançats (ICREA), Pg. Lluís Companys 23, 08010 Barcelona, Spain
- Institute of Genetics and Biophysics, CNR, 80131 Naples, Italy
| |
Collapse
|
179
|
Davidovic L, Durand N, Khalfallah O, Tabet R, Barbry P, Mari B, Sacconi S, Moine H, Bardoni B. A novel role for the RNA-binding protein FXR1P in myoblasts cell-cycle progression by modulating p21/Cdkn1a/Cip1/Waf1 mRNA stability. PLoS Genet 2013; 9:e1003367. [PMID: 23555284 PMCID: PMC3605292 DOI: 10.1371/journal.pgen.1003367] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2012] [Accepted: 01/21/2013] [Indexed: 12/14/2022] Open
Abstract
The Fragile X-Related 1 gene (FXR1) is a paralog of the Fragile X Mental Retardation 1 gene (FMR1), whose absence causes the Fragile X syndrome, the most common form of inherited intellectual disability. FXR1P plays an important role in normal muscle development, and its absence causes muscular abnormalities in mice, frog, and zebrafish. Seven alternatively spliced FXR1 transcripts have been identified and two of them are skeletal muscle-specific. A reduction of these isoforms is found in myoblasts from Facio-Scapulo Humeral Dystrophy (FSHD) patients. FXR1P is an RNA–binding protein involved in translational control; however, so far, no mRNA target of FXR1P has been linked to the drastic muscular phenotypes caused by its absence. In this study, gene expression profiling of C2C12 myoblasts reveals that transcripts involved in cell cycle and muscular development pathways are modulated by Fxr1-depletion. We observed an increase of p21—a regulator of cell-cycle progression—in Fxr1-knocked-down mouse C2C12 and FSHD human myoblasts. Rescue of this molecular phenotype is possible by re-expressing human FXR1P in Fxr1-depleted C2C12 cells. FXR1P muscle-specific isoforms bind p21 mRNA via direct interaction with a conserved G-quadruplex located in its 3′ untranslated region. The FXR1P/G-quadruplex complex reduces the half-life of p21 mRNA. In the absence of FXR1P, the upregulation of p21 mRNA determines the elevated level of its protein product that affects cell-cycle progression inducing a premature cell-cycle exit and generating a pool of cells blocked at G0. Our study describes a novel role of FXR1P that has crucial implications for the understanding of its role during myogenesis and muscle development, since we show here that in its absence a reduced number of myoblasts will be available for muscle formation/regeneration, shedding new light into the pathophysiology of FSHD. Muscle development is a complex process controlled by the timely expression of genes encoding crucial regulators of the muscle cell precursors called myoblasts. We know from previous studies that inactivation of the Fragile X related 1 (FXR1) gene in various animal models (mouse, frog, and zebrafish) causes muscular and cardiac abnormalities. Also, FXR1P is reduced in a human myopathy called Fascio-Scapulo Humeral Dystrophy (FSHD), suggesting its critical role in muscle that findings presented in this study contribute to elucidating. Cell-cycle arrest is a prerequisite to differentiation of myoblasts into mature myotubes, which will form the muscle. One key regulator is the p21/Cdkn1a/Cip1/Waf1 protein, which commands myoblasts to stop proliferating, and this action is particularly important during muscle regeneration. In this study, we have identified FXR1P as a novel regulator of p21 expression. We show that FXR1P absence in mouse myoblasts and FSHD-derived myopathic myoblasts increases abnormally the levels of p21, causing a premature cell cycle exit of myoblasts. Our study predicts that FXR1P absence leads to a reduced number of myoblasts available for muscle formation and regeneration. This explains the drastic effects of FXR1 inactivation on muscle and brings a better understanding of the molecular/cellular bases of FSHD.
Collapse
Affiliation(s)
- Laetitia Davidovic
- Institut de Pharmacologie Moléculaire et Cellulaire, CNRS UMR 7275, Valbonne, France
- Université de Nice-Sophia Antipolis, Nice, France
| | - Nelly Durand
- Institut de Pharmacologie Moléculaire et Cellulaire, CNRS UMR 7275, Valbonne, France
- Université de Nice-Sophia Antipolis, Nice, France
| | - Olfa Khalfallah
- Institut de Pharmacologie Moléculaire et Cellulaire, CNRS UMR 7275, Valbonne, France
- Université de Nice-Sophia Antipolis, Nice, France
| | - Ricardo Tabet
- IGBMC (Institut de Génétique et de Biologie Moléculaire et Cellulaire), CNRS, UMR7104, Inserm U596, Collège de France, Strasbourg University, Illkirch-Graffenstaden, France
| | - Pascal Barbry
- Institut de Pharmacologie Moléculaire et Cellulaire, CNRS UMR 7275, Valbonne, France
- Université de Nice-Sophia Antipolis, Nice, France
| | - Bernard Mari
- Institut de Pharmacologie Moléculaire et Cellulaire, CNRS UMR 7275, Valbonne, France
- Université de Nice-Sophia Antipolis, Nice, France
| | - Sabrina Sacconi
- INSERM U638, Faculté de Médecine, Université de Nice Sophia-Antipolis, Centre de Référence pour les Maladies Neuromusculaires, CHU de Nice, Nice, France
| | - Hervé Moine
- IGBMC (Institut de Génétique et de Biologie Moléculaire et Cellulaire), CNRS, UMR7104, Inserm U596, Collège de France, Strasbourg University, Illkirch-Graffenstaden, France
| | - Barbara Bardoni
- Institut de Pharmacologie Moléculaire et Cellulaire, CNRS UMR 7275, Valbonne, France
- Université de Nice-Sophia Antipolis, Nice, France
- * E-mail:
| |
Collapse
|
180
|
Zulfakar SS, White JD, Ross T, Tamplin ML. Cultured C2C12 cell lines as a model for assessment of bacterial attachment to bovine primary muscle cells. Meat Sci 2013; 94:215-9. [PMID: 23501253 DOI: 10.1016/j.meatsci.2013.01.017] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2012] [Revised: 01/24/2013] [Accepted: 01/25/2013] [Indexed: 11/30/2022]
Abstract
The mechanisms of bacterial attachment to meat tissues need to be understood to enhance meat safety interventions. However, little is known about attachment of foodborne pathogens to meat muscle cells. In this study, attachment of six Escherichia coli and two Salmonella strains to primary bovine muscle cells and a cultured muscle cell line, C2C12, was measured, including the effect of temperature. At 37°C, all but one strain (EC623) attached to C2C12 cells, whereas only five of eight strains (M23Sr, H10407, EC473, Sal1729a and Sal691) attached to primary cells. At 10 °C, two strains (H10407 and EC473) attached to C2C12 cells, compared to four strains (M23Sr, EC614, H10407 and Sal1729a) of primary cells. Comparing all strains at both temperatures, EC614 displayed the highest CFU per C2C12 cell (4.60±2.02CFU/muscle cell at 37 °C), whereas greater numbers of M23Sr attached per primary cell (51.88±39.43CFU/muscle cell at 37 °C). This study indicates that primary bovine muscle cells may provide a more relevant model system to study bacterial attachment to beef carcasses compared to cell lines such as C2C12.
Collapse
Affiliation(s)
- Siti Shahara Zulfakar
- Tasmanian Institute of Agriculture, Food Safety Centre, University of Tasmania, Private Bag 54, Hobart, TAS 7005, Australia
| | | | | | | |
Collapse
|
181
|
Vrijens K, Lin W, Cui J, Farmer D, Low J, Pronier E, Zeng FY, Shelat AA, Guy K, Taylor MR, Chen T, Roussel MF. Identification of small molecule activators of BMP signaling. PLoS One 2013; 8:e59045. [PMID: 23527084 PMCID: PMC3602516 DOI: 10.1371/journal.pone.0059045] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2012] [Accepted: 02/11/2013] [Indexed: 12/13/2022] Open
Abstract
Bone Morphogenetic Proteins (BMPs) are morphogens that play a major role in regulating development and homeostasis. Although BMPs are used for the treatment of bone and kidney disorders, their clinical use is limited due to the supra-physiological doses required for therapeutic efficacy causing severe side effects. Because recombinant BMPs are expensive to produce, small molecule activators of BMP signaling would be a cost-effective alternative with the added benefit of being potentially more easily deliverable. Here, we report our efforts to identify small molecule activators of BMP signaling. We have developed a cell-based assay to monitor BMP signaling by stably transfecting a BMP-responsive human cervical carcinoma cell line (C33A) with a reporter construct in which the expression of luciferase is driven by a multimerized BMP-responsive element from the Id1 promoter. A BMP-responsive clone C33A-2D2 was used to screen a bioactive library containing ∼5,600 small molecules. We identified four small molecules of the family of flavonoids all of which induced luciferase activity in a dose-dependent manner and ventralized zebrafish embryos. Two of the identified compounds induced Smad1, 5 phosphorylation (P-Smad), Id1 and Id2 expression in a dose-dependent manner demonstrating that our assays identified small molecule activators of BMP signaling.
Collapse
Affiliation(s)
- Karen Vrijens
- Departments of Tumor Cell Biology, Memphis, Tennessee, United States of America
| | - Wenwei Lin
- Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, Tennessee, United States of America
| | - Jimmy Cui
- Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, Tennessee, United States of America
| | - Dana Farmer
- Departments of Tumor Cell Biology, Memphis, Tennessee, United States of America
| | - Jonathan Low
- Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, Tennessee, United States of America
| | - Elodie Pronier
- Departments of Tumor Cell Biology, Memphis, Tennessee, United States of America
- Institut National de la Santé et de la Recherche Medicale, U1009, Institut Gustave Roussy, Villejuif, France
| | - Fu-Yue Zeng
- Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, Tennessee, United States of America
| | - Anang A. Shelat
- Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, Tennessee, United States of America
| | - Kiplin Guy
- Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, Tennessee, United States of America
| | - Michael R. Taylor
- Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, Tennessee, United States of America
| | - Taosheng Chen
- Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, Tennessee, United States of America
| | - Martine F. Roussel
- Departments of Tumor Cell Biology, Memphis, Tennessee, United States of America
- * E-mail:
| |
Collapse
|
182
|
Dearth CL, Goh Q, Marino JS, Cicinelli PA, Torres-Palsa MJ, Pierre P, Worth RG, Pizza FX. Skeletal muscle cells express ICAM-1 after muscle overload and ICAM-1 contributes to the ensuing hypertrophic response. PLoS One 2013; 8:e58486. [PMID: 23505517 PMCID: PMC3594308 DOI: 10.1371/journal.pone.0058486] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2012] [Accepted: 02/04/2013] [Indexed: 11/18/2022] Open
Abstract
We previously reported that leukocyte specific β2 integrins contribute to hypertrophy after muscle overload in mice. Because intercellular adhesion molecule-1 (ICAM-1) is an important ligand for β2 integrins, we examined ICAM-1 expression by murine skeletal muscle cells after muscle overload and its contribution to the ensuing hypertrophic response. Myofibers in control muscles of wild type mice and cultures of skeletal muscle cells (primary and C2C12) did not express ICAM-1. Overload of wild type plantaris muscles caused myofibers and satellite cells/myoblasts to express ICAM-1. Increased expression of ICAM-1 after muscle overload occurred via a β2 integrin independent mechanism as indicated by similar gene and protein expression of ICAM-1 between wild type and β2 integrin deficient (CD18-/-) mice. ICAM-1 contributed to muscle hypertrophy as demonstrated by greater (p<0.05) overload-induced elevations in muscle protein synthesis, mass, total protein, and myofiber size in wild type compared to ICAM-1-/- mice. Furthermore, expression of ICAM-1 altered (p<0.05) the temporal pattern of Pax7 expression, a marker of satellite cells/myoblasts, and regenerating myofiber formation in overloaded muscles. In conclusion, ICAM-1 expression by myofibers and satellite cells/myoblasts after muscle overload could serve as a mechanism by which ICAM-1 promotes hypertrophy by providing a means for cell-to-cell communication with β2 integrin expressing myeloid cells.
Collapse
Affiliation(s)
- Christopher L. Dearth
- Department of Kinesiology, The University of Toledo, Toledo, Ohio, United States of America
| | - Qingnian Goh
- Department of Kinesiology, The University of Toledo, Toledo, Ohio, United States of America
| | - Joseph S. Marino
- Department of Kinesiology, The University of Toledo, Toledo, Ohio, United States of America
| | - Peter A. Cicinelli
- Department of Kinesiology, The University of Toledo, Toledo, Ohio, United States of America
| | - Maria J. Torres-Palsa
- Department of Kinesiology, The University of Toledo, Toledo, Ohio, United States of America
| | - Philippe Pierre
- Centre d'Immunologie de Marseille-Luminy U2M, Aix-Marseille Université, Marseille, France
- INSERM U631, Institut National de la Santé et Recherche Médicale, Marseille, France
- CNRS UMR6102, Centre National de la Recherche Scientifique, Marseille, France
| | - Randall G. Worth
- College of Medicine and Life Sciences, The University of Toledo, Toledo, Ohio, United States of America
| | - Francis X. Pizza
- Department of Kinesiology, The University of Toledo, Toledo, Ohio, United States of America
- * E-mail:
| |
Collapse
|
183
|
|
184
|
Abstract
The crucial facts underlying the low efficiency of cellular reprogramming are poorly understood. Cellular reprogramming occurs in nuclear transfer, induced pluripotent stem cell (iPSC) formation, cell fusion, and lineage-switching experiments. Despite these advances, there are three fundamental problems to be addressed: (1) the majority of cells cannot be reprogrammed, (2) the efficiency of reprogramming cells is usually low, and (3) the reprogrammed cells developed from a patient's own cells activate immune responses. These shortcomings present major obstacles for using reprogramming approaches in customised cell therapy. In this Perspective, the author synthesises past and present observations in the field of cellular reprogramming to propose a theoretical picture of the cellular memory disc. The current hypothesis is that all cells undergo an endogenous and exogenous holographic memorisation such that parts of the cellular memory dramatically decrease the efficiency of reprogramming cells, act like a barrier against reprogramming in the majority of cells, and activate immune responses. Accordingly, the focus of this review is mainly to describe the cellular memory disc (CMD). Based on the present theory, cellular memory includes three parts: a reprogramming-resistance memory (RRM), a switch-promoting memory (SPM) and a culture-induced memory (CIM). The cellular memory arises genetically, epigenetically and non-genetically and affects cellular behaviours. [corrected].
Collapse
Affiliation(s)
- Seyed Hadi Anjamrooz
- Cellular and Molecular Research Center, School of Medicine, Kurdistan University of Medical Sciences, Sanandaj, Iran.
| |
Collapse
|
185
|
Ishida K, Haudenschild DR. Interactions between FGF21 and BMP-2 in osteogenesis. Biochem Biophys Res Commun 2013; 432:677-82. [PMID: 23416071 DOI: 10.1016/j.bbrc.2013.02.019] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2013] [Accepted: 02/06/2013] [Indexed: 12/13/2022]
Abstract
Lifestyle-related diseases are increasing and the challenge to create innovative drugs to treat such diseases is a main focus in medical science research. Fibroblast growth factor 21 (FGF21) is a powerful modulator of glucose and lipid metabolism, and is an innovative candidate drug already in clinical trials for type 2 diabetes mellitus and obesity. Bone fragility and impaired fracture healing induced by such lifestyle-related conditions are also a growing problem. Bone morphogenic proteins (BMPs) are well known osteogenic growth factors, and BMP-2 is used to augment bone formation in difficult clinical situations. There are many documented interactions between the FGF and BMP family proteins, although the interaction between FGF21 and BMP-2 remains unknown. The aim of this study was to reveal the effect of FGF21 toward BMP-2-dependent osteogenic activity, using C2C12 cells as a model system. We found that FGF21 enhanced BMP-2-dependent transcription and osteogenesis in the C2C12 cell line, which was confirmed by alkaline phosphatase activity, matrix mineralization, and gene expression. Mechanistically, FGF21 enhanced BMP-2-induced intracellular signaling through Smad proteins, but not through p44/42MAPK proteins. Furthermore, we identified a negative feedback loop in which BMP-2 decreased endogenous FGF21 mRNA expression. In summary, this study demonstrates interactions between BMP-2 and FGF21 pathways exist in vitro, and that FGF21 enhances the osteogenic activity of BMP-2 by up-regulating the BMP-2-dependent Smad signaling pathway.
Collapse
Affiliation(s)
- Kazunari Ishida
- Lawrence J.Ellison Musculoskeletal Research Center, Department of Orthopaedic Surgery, University of California Davis, 4635 Second Avenue, Sacramento, CA 95817, USA
| | | |
Collapse
|
186
|
Sancho-Martinez I, Baek SH, Izpisua Belmonte JC. Lineage conversion methodologies meet the reprogramming toolbox. Nat Cell Biol 2013; 14:892-9. [PMID: 22945254 DOI: 10.1038/ncb2567] [Citation(s) in RCA: 89] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Lineage conversion has recently attracted increasing attention as a potential alternative to the directed differentiation of pluripotent cells to obtain cells of a given lineage. Different means allowing for cell identity switch have been reported. Lineage conversion relied initially on the discovery of specific transcription factors generally enriched and characteristic of the target cell, and their forced expression in cells of a different fate. This approach has been successful in various cases, from cells of the hematopoietic systems to neurons and cardiomyocytes. Furthermore, recent reports have suggested the possibility of establishing a general lineage conversion approach bypassing pluripotency. This requires a first phase of epigenetic erasure achieved by short overexpression of the factors used to reprogram cells to a pluripotent state (such as a combination of Sox2, Klf4, c-Myc and Oct4), followed by exposure to specific developmental cues. Here we present these different direct conversion methodologies and discuss their potential as alternatives to using induced pluripotent stem cells and differentiation protocols to generate cell populations of a given fate.
Collapse
Affiliation(s)
- Ignacio Sancho-Martinez
- Gene Expression Laboratory, Salk Institute for Biological Studies, La Jolla, California 92037, USA
| | | | | |
Collapse
|
187
|
Sparrow DB, McInerney-Leo A, Gucev ZS, Gardiner B, Marshall M, Leo PJ, Chapman DL, Tasic V, Shishko A, Brown MA, Duncan EL, Dunwoodie SL. Autosomal dominant spondylocostal dysostosis is caused by mutation in TBX6. Hum Mol Genet 2013; 22:1625-31. [DOI: 10.1093/hmg/ddt012] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
|
188
|
Goustin AS, Derar N, Abou-Samra AB. Ahsg-fetuin blocks the metabolic arm of insulin action through its interaction with the 95-kD β-subunit of the insulin receptor. Cell Signal 2013; 25:981-8. [PMID: 23314177 DOI: 10.1016/j.cellsig.2012.12.011] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2012] [Revised: 11/10/2012] [Accepted: 12/19/2012] [Indexed: 12/22/2022]
Abstract
We previously have shown that Ahsg, a liver glycoprotein, inhibits insulin receptor (InsR) tyrosine kinase (TK) activity and the ERK1/2 mitogenic signaling arm of insulin signaling. Here we show that Ahsg blocks insulin-stimulated GLUT4 translocation and Akt activation in intact cells (mouse myoblasts). Furthermore, Ahsg inhibits InsR autophosphorylation of highly-purified insulin holoreceptors in a cell-free, ATP-dependent system, with an IC50 within the range of single-chain Ahsg concentrations in human serum. Binding of (125)I-insulin to living cells overexpressing the InsR shows a dissociation constant (KD) of 250pM, unaltered in the presence of 300 nM Ahsg. A mutant InsR cDNA encoding the signal peptide, the β-subunit and the furin processing site, but deleting the α-subunit, was stably expressed in HEK293 cells. Treatment with peroxovanadate, but not insulin, dramatically increased the 95 kD β-subunit tyrosine phosphoryation. The level of tyrosine phosphorylation of the 95-kD β-subunit can be driven down sharply by treatment of living HEK293 transfectant cells with physiological doses of Ahsg. Treatment of myogenic cells with Ahsg blunts insulin-stimulated InsR autophosphorylation and AKT phosphorylation. Taken together, we show that Ahsg antagonizes the metabolic functions initiated by InsR activation without interference in insulin binding. The experiments suggest a direct interaction of Ahsg with the InsR ectodomain β-subunit in a mode that does not significantly alter the high-affinity binding of insulin to the holoreceptor's two complementing α-subunits.
Collapse
Affiliation(s)
- Anton Scott Goustin
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, Wayne State University School of Medicine, Detroit, MI, USA.
| | | | | |
Collapse
|
189
|
Abstract
This article discusses current understanding of myocardial biology, emphasizing the regeneration potential of the adult human heart and the mechanisms involved. In the last decade, a novel conceptual view has emerged. The heart is no longer considered a postmitotic organ, but is viewed as a self-renewing organ characterized by a resident stem cell compartment responsible for tissue homeostasis and cardiac repair following injury. Additionally, HSCs possess the ability to transdifferentiate and acquire the cardiomyocyte, vascular endothelial, and smooth muscle cell lineages. Both cardiac and hematopoietic stem cells may be used therapeutically in an attempt to reverse the devastating consequences of chronic heart failure of ischemic and nonischemic origin.
Collapse
Affiliation(s)
- Piero Anversa
- Department of Anesthesia and Division of Cardiovascular Medicine, 75 Francis Street, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts, USA.
| | | | | | | |
Collapse
|
190
|
Morris SA, Daley GQ. A blueprint for engineering cell fate: current technologies to reprogram cell identity. Cell Res 2013; 23:33-48. [PMID: 23277278 DOI: 10.1038/cr.2013.1] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Human diseases such as heart failure, diabetes, neurodegenerative disorders, and many others result from the deficiency or dysfunction of critical cell types. Strategies for therapeutic tissue repair or regeneration require the in vitro manufacture of clinically relevant quantities of defined cell types. In addition to transplantation therapy, the generation of otherwise inaccessible cells also permits disease modeling, toxicology testing and drug discovery in vitro. In this review, we discuss current strategies to manipulate the identity of abundant and accessible cells by differentiation from an induced pluripotent state or direct conversion between differentiated states. We contrast these approaches with recent advances employing partial reprogramming to facilitate lineage switching, and discuss the mechanisms underlying the engineering of cell fate. Finally, we address the current limitations of the field and how the resulting cell types can be assessed to ensure the production of medically relevant populations.
Collapse
Affiliation(s)
- Samantha A Morris
- Stem Cell Transplantation Program, Division of Pediatric Hematology and Oncology, Manton Center for Orphan Disease Research, Howard Hughes Medical Institute, Children's Hospital Boston and Dana Farber Cancer Institute, Boston, MA, USA
| | | |
Collapse
|
191
|
K. Ball M, H. Campbell D, Ezell K, B. Henley J, R. Standley P, A. Grow W. Antibody to MyoD or Myogenin Decreases Acetylcholine Receptor Clustering in C2C12 Myotube Culture. Cell 2013. [DOI: 10.4236/cellbio.2013.23016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
192
|
Abstract
During development, diverse cellular identities are established and maintained in the embryo. Although remarkably robust in vivo, cellular identities can be manipulated using experimental techniques. Lineage reprogramming is an emerging field at the intersection of developmental and stem cell biology in which a somatic cell is stably reprogrammed into a distinct cell type by forced expression of lineage-determining factors. Lineage reprogramming enables the direct conversion of readily available cells from patients (such as skin fibroblasts) into disease-relevant cell types (such as neurons and cardiomyocytes) or into induced pluripotent stem cells. Although remarkable progress has been made in developing novel reprogramming methods, the efficiency and fidelity of reprogramming need to be improved in order increase the experimental and translational utility of reprogrammed cells. Studying the mechanisms that prevent successful reprogramming should allow for improvements in reprogramming methods, which could have significant implications for regenerative medicine and the study of human disease. Furthermore, lineage reprogramming has the potential to become a powerful system for dissecting the mechanisms that underlie cell fate establishment and terminal differentiation processes. In this review, we will discuss how transcription factors interface with the genome and induce changes in cellular identity in the context of development and reprogramming.
Collapse
Affiliation(s)
- Thomas Vierbuchen
- Institute for Stem Cell Biology and Regenerative Medicine, Department of Pathology, and Cancer Biology Program, Stanford University School of Medicine, Stanford, CA 94305, USA
| | | |
Collapse
|
193
|
Bhutani N, Decker MN, Brady JJ, Bussat RT, Burns DM, Corbel SY, Blau HM. A critical role for AID in the initiation of reprogramming to induced pluripotent stem cells. FASEB J 2012; 27:1107-13. [PMID: 23212122 DOI: 10.1096/fj.12-222125] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Mechanistic insights into the reprogramming of fibroblasts to induced pluripotent stem cells (iPSCs) are limited, particularly for early acting molecular regulators. Here we use an acute loss of function approach to demonstrate that activation-induced deaminase (AID) activity is necessary for the initiation of reprogramming to iPSCs. While AID is well known for antibody diversification, it has also recently been shown to have a role in active DNA demethylation in reprogramming toward pluripotency and development. These findings suggested a potential role for AID in iPSC generation, yet, iPSC yield from AID-knockout mouse fibroblasts was similar to that of wild-type (WT) fibroblasts. We reasoned that an acute loss of AID function might reveal effects masked by compensatory mechanisms during development, as reported for other proteins. Accordingly, we induced an acute reduction (>50%) in AID levels using 4 different shRNAs and determined that reprogramming to iPSCs was significantly impaired by 79 ± 7%. The deaminase activity of AID was critical, as coexpression of WT but not a catalytic mutant AID rescued reprogramming. Notably, AID was required only during a 72-h time window at the onset of iPSC reprogramming. Our findings show a critical role for AID activity in the initiation of reprogramming to iPSCs.
Collapse
Affiliation(s)
- Nidhi Bhutani
- Baxter Laboratory for Stem Cell Biology, Institute for Stem Cell Biology and Regenerative Medicine, Department of Microbiology and Immunology, Stanford University, Stanford, CA 94305-5175, USA
| | | | | | | | | | | | | |
Collapse
|
194
|
Sharples AP, Player DJ, Martin NRW, Mudera V, Stewart CE, Lewis MP. Modelling in vivo skeletal muscle ageing in vitro using three-dimensional bioengineered constructs. Aging Cell 2012; 11:986-95. [PMID: 22882433 DOI: 10.1111/j.1474-9726.2012.00869.x] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Degeneration of skeletal muscle (SkM) with age (sarcopenia) is a major contributor to functional decline, morbidity and mortality. Methodological implications often make it difficult to embark on interventions in already frail and diseased elderly individuals. Using in vitro three-dimensional (3D) bioengineered skeletal muscle constructs that model aged phenotypes and incorporate a representative extracellular matrix (collagen), are under tension, and display morphological and transcript expression of mature skeletal muscle may more accurately characterize the SkM niche. Furthermore, an in vitro model would provide greater experimental manipulation with regard to gene, pharmacological and exercise (mechanical stretch/electrical stimulation) therapies and thus strategies for combating muscle wasting with age. The present study utilized multiple population-doubled (MPD) murine myoblasts compared with parental controls (CON), previously shown to have an aged phenotype in monolayer cultures (Sharples et al., 2011), seeded into 3D type I collagen matrices under uniaxial tension. 3D bioengineered constructs incorporating MPD cells had reduced myotube size and diameter vs. CON constructs. MPD constructs were characterized by reduced peak force development over 24 h after cell seeding, reduced transcript expression of remodelling matrix metalloproteinases, MMP2 and MMP9, with reduced differentiation/hypertrophic potential shown by reduced IGF-I, IGF-IR, IGF-IEa, MGF mRNA. Increased IGFBP2 and myostatin in MPD vs. CON constructs also suggested impaired differentiation/reduced regenerative potential. Overall, 3D bioengineered skeletal muscle constructs represent an in vitro model of the in vivo cell niche with MPD constructs displaying similar characteristics to ageing/atrophied muscle in vivo, thus potentially providing a future test bed for therapeutic interventions to contest muscle degeneration with age.
Collapse
Affiliation(s)
- Adam P Sharples
- Muscle Cellular and Molecular Physiology Research Group (MCMPRG), Institute for Sport and Physical Activity Research (ISPAR Bedford), University of Bedfordshire, Bedford, UK.
| | | | | | | | | | | |
Collapse
|
195
|
Brzoska E, Kowalewska M, Markowska-Zagrajek A, Kowalski K, Archacka K, Zimowska M, Grabowska I, Czerwińska AM, Czarnecka-Góra M, Stremińska W, Jańczyk-Ilach K, Ciemerych MA. Sdf-1 (CXCL12) improves skeletal muscle regeneration via the mobilisation of Cxcr4 and CD34 expressing cells. Biol Cell 2012; 104:722-37. [PMID: 22978573 DOI: 10.1111/boc.201200022] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2012] [Accepted: 09/11/2012] [Indexed: 01/27/2023]
Abstract
BACKGROUND INFORMATION The regeneration of skeletal muscles involves satellite cells, which are muscle-specific precursor cells. In muscles, injured either mechanically or as a consequence of a disease, such as muscular dystrophy, local release of the growth factors and cytokines leads to satellite cells activation, proliferation and differentiation of the resulting myoblasts, followed by the formation of new myofibres. Various cell types, such as stem and progenitor cells, originating from other tissues different than the muscle, are also able to follow a myogenic program. Participation of these cells in the repair process depends on their precise mobilisation to the site of the injury. RESULTS In this study, we showed that stromal-derived factor-1 (Sdf-1) impacts on the mobilisation of CXC chemokine receptor (Cxcr)4-positive cells and improves skeletal muscle regeneration. Analysis of isolated and in vitro cultured satellite cells showed that Sdf-1 did not influence myoblasts proliferation and expression of myogenic regulatory transcription factors but induced migration of the myoblasts in Cxcr4-dependent ways. This phenomenon was also associated with the increased activity of crucial extracellular matrix modifiers, i.e. metalloproteases Mmp-2 and Mmp-9. CONCLUSIONS Thus, positive impact of Sdf-1 on muscle regeneration is related to the mobilisation of endogenous cells, that is satellite cells and myoblasts, as well as non-muscle stem cells, expressing Cxcr4 and CD34.
Collapse
Affiliation(s)
- Edyta Brzoska
- Department of Cytology, Faculty of Biology, University of Warsaw, Warsaw 02-096, Poland.
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
196
|
Pereira CF, Lemischka IR, Moore K. Reprogramming cell fates: insights from combinatorial approaches. Ann N Y Acad Sci 2012; 1266:7-17. [PMID: 22901251 DOI: 10.1111/j.1749-6632.2012.06508.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Epigenetic reprogramming can be achieved in different ways, including nuclear transfer, cell fusion, or the expression of transcription factors (TFs). Combinatorial overexpression provides an opportunity to define the minimal core network of TFs that instructs specific cell fates. This approach has been employed to induce mouse and human pluripotency and differentiated cell types from cells that can be also as distant as cells from different germ layers. This suggests the possibility that any specific cell type may be directly converted into another if the appropriate reprogramming TF core is determined. Herein, we review the factors used for reprogramming multiple cell identities and raise the question of whether there is a common underlying blueprint for reprogramming factors. In addition to the generation of human cell types of interest for cell-replacement therapies, we propose that the TF-mediated conversion of differentiated cell types, especially somatic stem cells, will have an impact on our understanding of their biological development.
Collapse
Affiliation(s)
- Carlos-Filipe Pereira
- Department of Developmental and Regenerative Biology, Black Family Stem Cell Institute, Mount Sinai School of Medicine, New York, New York, USA.
| | | | | |
Collapse
|
197
|
Nizzardo M, Simone C, Falcone M, Riboldi G, Comi GP, Bresolin N, Corti S. Direct reprogramming of adult somatic cells into other lineages: past evidence and future perspectives. Cell Transplant 2012; 22:921-44. [PMID: 23044010 DOI: 10.3727/096368912x657477] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Direct reprogramming of an adult cell into another differentiated lineage-such as fibroblasts into neurons, cardiomyocytes, or blood cells-without passage through an undifferentiated pluripotent stage is a new area of research that has recently emerged alongside stem cell technology and induced pluripotent stem cell reprogramming; indeed, this avenue of investigation has begun to play a central role in basic biological research and regenerative medicine. Even though the field seems new, its origins go back to the 1980s when it was demonstrated that differentiated adult cells can be converted into another cell lineage through the overexpression of transcription factors, establishing mature cell plasticity. Here, we retrace transdifferentiation experiments from the discovery of master control genes to recent in vivo reprogramming of one somatic cell into another from the perspective of possible applications for the development of new therapeutic approaches for human diseases.
Collapse
Affiliation(s)
- Monica Nizzardo
- Department of Neurological Sciences, Dino Ferrari Centre, University of Milan, IRCCS Foundation Ca' Granda, Ospedale Maggiore Policlinico, Milan, Italy
| | | | | | | | | | | | | |
Collapse
|
198
|
Blau H. Helen Blau: she thinks like a cell. Interview by Ruth Williams. Circ Res 2012; 111:672-4. [PMID: 22935532 DOI: 10.1161/circresaha.112.277863] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
|
199
|
Benedusi V, Martorana F, Brambilla L, Maggi A, Rossi D. The peroxisome proliferator-activated receptor γ (PPARγ) controls natural protective mechanisms against lipid peroxidation in amyotrophic lateral sclerosis. J Biol Chem 2012; 287:35899-911. [PMID: 22910911 PMCID: PMC3476258 DOI: 10.1074/jbc.m112.366419] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Recent evidence highlights the peroxisome proliferator-activated receptors (PPARs) as critical neuroprotective factors in several neurodegenerative diseases, including amyotrophic lateral sclerosis (ALS). To gain new mechanistic insights into the role of these receptors in the context of ALS, here we investigated how PPAR transcriptional activity varies in hSOD1G93A ALS transgenic mice. We demonstrate that PPARγ-driven transcription selectively increases in the spinal cord of symptomatic hSOD1G93A mice. This phenomenon correlates with the up-regulation of target genes, such as lipoprotein lipase and glutathione S-transferase α-2, which are implicated in scavenging lipid peroxidation by-products. Such events are associated with enhanced PPARγ immunoreactivity within motor neuronal nuclei. This observation, and the fact that PPARγ displays increased responsiveness in cultured hSOD1G93A motor neurons, points to a role for this receptor in neutralizing deleterious lipoperoxidation derivatives within the motor cells. Consistently, in both motor neuron-like cultures and animal models, we report that PPARγ is activated by lipid peroxidation end products, such as 4-hydroxynonenal, whose levels are elevated in the cerebrospinal fluid and spinal cord from ALS patients. We propose that the accumulation of critical concentrations of lipid peroxidation adducts during ALS progression leads to the activation of PPARγ in motor neurons. This in turn triggers self-protective mechanisms that involve the up-regulation of lipid detoxification enzymes, such as lipoprotein lipase and glutathione S-transferase α-2. Our findings indicate that anticipating natural protective reactions by pharmacologically modulating PPARγ transcriptional activity may attenuate neurodegeneration by limiting the damage induced by lipid peroxidation derivatives.
Collapse
Affiliation(s)
- Valeria Benedusi
- Center of Excellence on Neurodegenerative Diseases and Department of Pharmacological and Biomolecular Sciences, University of Milan, 20133 Milan, Italy
| | | | | | | | | |
Collapse
|
200
|
Abstract
Stem cells have captured our imagination and generated hope, representing a source of replacement cells to treat a host of medical conditions. Tucked away in specialized niches, stem cells maintain tissue function and rejuvenate organs. Balancing the equation between cellular supply and demand is especially important in the adult brain, as neural stem cells (NSCs) in two discrete regions, the subgranular zone (SGZ) of the dentate gyrus and the subventricular zone (SVZ) next to the lateral ventricles, continuously self-renew and differentiate into neurons in a process called adult neurogenesis. Through the interplay of intrinsic and extrinsic factors, adult neurogenic niches ensure neuronal turnover throughout life, contributing to plasticity and homeostatic processes in the brain. This review summarizes recent progress on the molecular control of adult neurogenesis in the SGZ and SVZ, focusing on the role of specific transcription factors that mediate the progression from NSCs to lineage-committed progenitors and, ultimately, the generation of mature neurons and glia.
Collapse
Affiliation(s)
- Jenny Hsieh
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA.
| |
Collapse
|