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Stadhouders LEM, Smith JAB, Gabriel BM, Verbrugge SAJ, Hammersen TD, Kolijn D, Vogel ISP, Mohamed AD, de Wit GMJ, Offringa C, Hoogaars WMH, Gehlert S, Wackerhage H, Jaspers RT. Myotube growth is associated with cancer-like metabolic reprogramming and is limited by phosphoglycerate dehydrogenase. Exp Cell Res 2023; 433:113820. [PMID: 37879549 DOI: 10.1016/j.yexcr.2023.113820] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 10/10/2023] [Accepted: 10/14/2023] [Indexed: 10/27/2023]
Abstract
The Warburg effect links growth and glycolysis in cancer. A key purpose of the Warburg effect is to generate glycolytic intermediates for anabolic reactions, such as nucleotides → RNA/DNA and amino acids → protein synthesis. The aim of this study was to investigate whether a similar 'glycolysis-for-anabolism' metabolic reprogramming also occurs in hypertrophying skeletal muscle. To interrogate this, we first induced C2C12 myotube hypertrophy with IGF-1. We then added 14C glucose to the differentiation medium and measured radioactivity in isolated protein and RNA to establish whether 14C had entered anabolism. We found that especially protein became radioactive, suggesting a glucose → glycolytic intermediates → non-essential amino acid(s) → protein series of reactions, the rate of which was increased by IGF-1. Next, to investigate the importance of glycolytic flux and non-essential amino acid synthesis for myotube hypertrophy, we exposed C2C12 and primary mouse myotubes to the glycolysis inhibitor 2-Deoxy-d-glucose (2DG). We found that inhibiting glycolysis lowered C2C12 and primary myotube size. Similarly, siRNA silencing of PHGDH, the key enzyme of the serine biosynthesis pathway, decreased C2C12 and primary myotube size; whereas retroviral PHGDH overexpression increased C2C12 myotube size. Together these results suggest that glycolysis is important for hypertrophying myotubes, which reprogram their metabolism to facilitate anabolism, similar to cancer cells.
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Affiliation(s)
- Lian E M Stadhouders
- Laboratory for Myology, Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, De Boelelaan 1108, 1081 HZ, Amsterdam, the Netherlands
| | - Jonathon A B Smith
- School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Foresterhill, Aberdeen, AB25 2ZD, UK; Department of Physiology and Pharmacology (FYFA), Group of Integrative Physiology, Karolinska Institutet, Stockholm, Sweden
| | - Brendan M Gabriel
- Aberdeen Cardiovascular & Diabetes Centre, The Rowett Institute, University of Aberdeen, Aberdeen, UK
| | - Sander A J Verbrugge
- Exercise Biology, Department for Sport and Health Sciences, Technical University of Munich, Georg-Brauchle-Ring 60/62, 80992, München/Munich, Germany
| | - Tim D Hammersen
- Laboratory for Myology, Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, De Boelelaan 1108, 1081 HZ, Amsterdam, the Netherlands
| | - Detmar Kolijn
- Laboratory for Myology, Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, De Boelelaan 1108, 1081 HZ, Amsterdam, the Netherlands; Department of Clinical Pharmacology and Molecular Cardiology, Ruhr University Bochum, Bochum, Germany
| | - Ilse S P Vogel
- Laboratory for Myology, Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, De Boelelaan 1108, 1081 HZ, Amsterdam, the Netherlands
| | - Abdalla D Mohamed
- School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Foresterhill, Aberdeen, AB25 2ZD, UK; Cancer Therapeutics Unit, Target Genomic and Chromosomal Instability, The Institute of Cancer Research, 15 Cotswold Road, Sutton, London, SM2 5NG, UK
| | - Gerard M J de Wit
- Laboratory for Myology, Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, De Boelelaan 1108, 1081 HZ, Amsterdam, the Netherlands
| | - Carla Offringa
- Laboratory for Myology, Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, De Boelelaan 1108, 1081 HZ, Amsterdam, the Netherlands
| | - Willem M H Hoogaars
- Laboratory for Myology, Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, De Boelelaan 1108, 1081 HZ, Amsterdam, the Netherlands
| | - Sebastian Gehlert
- Department for the Biosciences of Sports, Institute of Sports Science, University of Hildesheim, Universitätsplatz 1, 31141, Hildesheim, Germany; Department for Molecular and Cellular Sports Medicine, German Sport University Cologne, 50933, Cologne, Germany
| | - Henning Wackerhage
- Exercise Biology, Department for Sport and Health Sciences, Technical University of Munich, Georg-Brauchle-Ring 60/62, 80992, München/Munich, Germany
| | - Richard T Jaspers
- Laboratory for Myology, Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, De Boelelaan 1108, 1081 HZ, Amsterdam, the Netherlands.
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2
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Hillege MMG, Shi A, Galli RA, Wu G, Bertolino P, Hoogaars WMH, Jaspers RT. Lack of Tgfbr1 and Acvr1b synergistically stimulates myofibre hypertrophy and accelerates muscle regeneration. eLife 2022; 11:77610. [PMID: 35323108 PMCID: PMC9005187 DOI: 10.7554/elife.77610] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Accepted: 03/05/2022] [Indexed: 12/02/2022] Open
Abstract
In skeletal muscle, transforming growth factor-β (TGF-β) family growth factors, TGF-β1 and myostatin, are involved in atrophy and muscle wasting disorders. Simultaneous interference with their signalling pathways may improve muscle function; however, little is known about their individual and combined receptor signalling. Here, we show that inhibition of TGF-β signalling by simultaneous muscle-specific knockout of TGF-β type I receptors Tgfbr1 and Acvr1b in mice, induces substantial hypertrophy, while such effect does not occur by single receptor knockout. Hypertrophy is induced by increased phosphorylation of Akt and p70S6K and reduced E3 ligases expression, while myonuclear number remains unaltered. Combined knockout of both TGF-β type I receptors increases the number of satellite cells, macrophages and improves regeneration post cardiotoxin-induced injury by stimulating myogenic differentiation. Extra cellular matrix gene expression is exclusively elevated in muscle with combined receptor knockout. Tgfbr1 and Acvr1b are synergistically involved in regulation of myofibre size, regeneration, and collagen deposition.
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Affiliation(s)
- Michèle M G Hillege
- Department of Human Movement, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| | - Andi Shi
- Department of Human Movement, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| | - Ricardo A Galli
- Department of Human Movement, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| | - Gang Wu
- Department of Oral and Maxillofacial Surgery/Pathology, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| | - Philippe Bertolino
- Centre de Recherche en Cancérologie de Lyon, Université de Lyon, UMR INSERM U1052, CNRS 5286, Lyon, France
| | - Willem M H Hoogaars
- Department of Human Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| | - Richard T Jaspers
- Department of Human Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
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3
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Haroon M, Boers HE, Bakker AD, Bloks NGC, Hoogaars WMH, Giordani L, Musters RJP, Deldicque L, Koppo K, Le Grand F, Klein-Nulend J, Jaspers RT. Reduced growth rate of aged muscle stem cells is associated with impaired mechanosensitivity. Aging (Albany NY) 2022; 14:28-53. [PMID: 35023852 PMCID: PMC8791224 DOI: 10.18632/aging.203830] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Accepted: 01/03/2022] [Indexed: 11/25/2022]
Abstract
Aging-associated muscle wasting and impaired regeneration are caused by deficiencies in muscle stem cell (MuSC) number and function. We postulated that aged MuSCs are intrinsically impaired in their responsiveness to omnipresent mechanical cues through alterations in MuSC morphology, mechanical properties, and number of integrins, culminating in impaired proliferative capacity. Here we show that aged MuSCs exhibited significantly lower growth rate and reduced integrin-α7 expression as well as lower number of phospho-paxillin clusters than young MuSCs. Moreover, aged MuSCs were less firmly attached to matrigel-coated glass substrates compared to young MuSCs, as 43% of the cells detached in response to pulsating fluid shear stress (1 Pa). YAP nuclear localization was 59% higher than in young MuSCs, yet YAP target genes Cyr61 and Ctgf were substantially downregulated. When subjected to pulsating fluid shear stress, aged MuSCs exhibited reduced upregulation of proliferation-related genes. Together these results indicate that aged MuSCs exhibit impaired mechanosensitivity and growth potential, accompanied by altered morphology and mechanical properties as well as reduced integrin-α7 expression. Aging-associated impaired muscle regenerative capacity and muscle wasting is likely due to aging-induced intrinsic MuSC alterations and dysfunctional mechanosensitivity.
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Affiliation(s)
- Mohammad Haroon
- Laboratory for Myology, Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Amsterdam 1081 HZ, The Netherlands
| | - Heleen E Boers
- Laboratory for Myology, Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Amsterdam 1081 HZ, The Netherlands
| | - Astrid D Bakker
- Department of Oral Cell Biology, Academic Centre for Dentistry Amsterdam, University of Amsterdam and Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Amsterdam 1081 LA, The Netherlands
| | - Niek G C Bloks
- Laboratory for Myology, Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Amsterdam 1081 HZ, The Netherlands
| | - Willem M H Hoogaars
- Laboratory for Myology, Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Amsterdam 1081 HZ, The Netherlands
| | - Lorenzo Giordani
- Sorbonne Université, INSERM UMRS974, Center for Research in Myology, Paris 75013, France
| | - René J P Musters
- Department of Physiology, Amsterdam University Medical Center VUmc, Amsterdam Cardiovascular Sciences, Amsterdam 1081 HZ, The Netherlands
| | - Louise Deldicque
- Institute of Neuroscience, Université Catholique de Louvain, Louvain-la-Neuve 1348, Belgium
| | - Katrien Koppo
- Exercise Physiology Research Group, Department of Movement Sciences, KU Leuven, Leuven 3001, Belgium
| | - Fabien Le Grand
- Faculty of Medicine and Pharmacy, NeuroMyoGène UCBL-CNRS UMR 5310, INSERM U1217, Lyon 69008, France
| | - Jenneke Klein-Nulend
- Department of Oral Cell Biology, Academic Centre for Dentistry Amsterdam, University of Amsterdam and Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Amsterdam 1081 LA, The Netherlands
| | - Richard T Jaspers
- Laboratory for Myology, Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Amsterdam 1081 HZ, The Netherlands
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Borghesan M, Hoogaars WMH, Varela-Eirin M, Talma N, Demaria M. A Senescence-Centric View of Aging: Implications for Longevity and Disease. Trends Cell Biol 2020; 30:777-791. [PMID: 32800659 DOI: 10.1016/j.tcb.2020.07.002] [Citation(s) in RCA: 118] [Impact Index Per Article: 29.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Revised: 07/03/2020] [Accepted: 07/10/2020] [Indexed: 01/10/2023]
Abstract
Cellular senescence is a state of stable cell cycle arrest associated with macromolecular alterations and secretion of proinflammatory cytokines and molecules. From their initial discovery in the 1960s, senescent cells have been hypothesized as potential contributors to the age-associated loss of regenerative potential. Here, we discuss recent evidence that implicates cellular senescence as a central regulatory mechanism of the aging process. We provide a comprehensive overview of age-associated pathologies in which cellular senescence has been implicated. We describe mechanisms by which senescent cells drive aging and diseases, and we discuss updates on exploiting these mechanisms as therapeutic targets. Finally, we critically analyze the use of senotherapeutics and their translation to the clinic, highlighting limitations and suggesting ideas for future applications and developments.
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Affiliation(s)
- M Borghesan
- European Research Institute for the Biology of Ageing (ERIBA);, University Medical Center Groningen (UMCG), University of Groningen, Antonius Deusinglaan 1, 9715RA, Groningen, The Netherlands
| | - W M H Hoogaars
- European Research Institute for the Biology of Ageing (ERIBA);, University Medical Center Groningen (UMCG), University of Groningen, Antonius Deusinglaan 1, 9715RA, Groningen, The Netherlands
| | - M Varela-Eirin
- European Research Institute for the Biology of Ageing (ERIBA);, University Medical Center Groningen (UMCG), University of Groningen, Antonius Deusinglaan 1, 9715RA, Groningen, The Netherlands
| | - N Talma
- European Research Institute for the Biology of Ageing (ERIBA);, University Medical Center Groningen (UMCG), University of Groningen, Antonius Deusinglaan 1, 9715RA, Groningen, The Netherlands
| | - M Demaria
- European Research Institute for the Biology of Ageing (ERIBA);, University Medical Center Groningen (UMCG), University of Groningen, Antonius Deusinglaan 1, 9715RA, Groningen, The Netherlands.
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5
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Hillege MMG, Galli Caro RA, Offringa C, de Wit GMJ, Jaspers RT, Hoogaars WMH. TGF-β Regulates Collagen Type I Expression in Myoblasts and Myotubes via Transient Ctgf and Fgf-2 Expression. Cells 2020; 9:E375. [PMID: 32041253 PMCID: PMC7072622 DOI: 10.3390/cells9020375] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2020] [Revised: 01/30/2020] [Accepted: 02/03/2020] [Indexed: 12/27/2022] Open
Abstract
Transforming Growth Factor β (TGF-β) is involved in fibrosis as well as the regulation of muscle mass, and contributes to the progressive pathology of muscle wasting disorders. However, little is known regarding the time-dependent signalling of TGF-β in myoblasts and myotubes, as well as how TGF-β affects collagen type I expression and the phenotypes of these cells. Here, we assessed effects of TGF-β on gene expression in C2C12 myoblasts and myotubes after 1, 3, 9, 24 and 48 h treatment. In myoblasts, various myogenic genes were repressed after 9, 24 and 48 h, while in myotubes only a reduction in Myh3 expression was observed. In both myoblasts and myotubes, TGF-β acutely induced the expression of a subset of genes involved in fibrosis, such as Ctgf and Fgf-2, which was subsequently followed by increased expression of Col1a1. Knockdown of Ctgf and Fgf-2 resulted in a lower Col1a1 expression level. Furthermore, the effects of TGF-β on myogenic and fibrotic gene expression were more pronounced than those of myostatin, and knockdown of TGF-β type I receptor Tgfbr1, but not receptor Acvr1b, resulted in a reduction in Ctgf and Col1a1 expression. These results indicate that, during muscle regeneration, TGF-β induces fibrosis via Tgfbr1 by stimulating the autocrine signalling of Ctgf and Fgf-2.
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Affiliation(s)
| | | | | | | | - Richard T. Jaspers
- Laboratory for Myology, Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, 1081 BT Amsterdam, The Netherlands; (M.M.G.H.); (R.A.G.C.); (C.O.); (G.M.J.d.W.); (W.M.H.H.)
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6
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Leonhard WN, Kunnen SJ, Plugge AJ, Pasternack A, Jianu SBT, Veraar K, El Bouazzaoui F, Hoogaars WMH, Ten Dijke P, Breuning MH, De Heer E, Ritvos O, Peters DJM. Inhibition of Activin Signaling Slows Progression of Polycystic Kidney Disease. J Am Soc Nephrol 2016; 27:3589-3599. [PMID: 27020852 PMCID: PMC5118473 DOI: 10.1681/asn.2015030287] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Accepted: 02/10/2016] [Indexed: 12/31/2022] Open
Abstract
Autosomal dominant polycystic kidney disease (ADPKD), characterized by the formation of numerous kidney cysts, is caused by PKD1 or PKD2 mutations and affects 0.1% of the population. Although recent clinical studies indicate that reduction of cAMP levels slows progression of PKD, this finding has not led to an established safe and effective therapy for patients, indicating the need to find new therapeutic targets. The role of TGF-β in PKD is not clearly understood, but nuclear accumulation of phosphorylated SMAD2/3 in cyst-lining cells suggests the involvement of TGF-β signaling in this disease. In this study, we ablated the TGF-β type 1 receptor (also termed activin receptor-like kinase 5) in renal epithelial cells of PKD mice, which had little to no effect on the expression of SMAD2/3 target genes or the progression of PKD. Therefore, we investigated whether alternative TGF-β superfamily ligands account for SMAD2/3 activation in cystic epithelial cells. Activins are members of the TGF-β superfamily and drive SMAD2/3 phosphorylation via activin receptors, but activins have not been studied in the context of PKD. Mice with PKD had increased expression of activin ligands, even at early stages of disease. In addition, treatment with a soluble activin receptor IIB fusion (sActRIIB-Fc) protein, which acts as a soluble trap to sequester activin ligands, effectively inhibited cyst formation in three distinct mouse models of PKD. These data point to activin signaling as a key pathway in PKD and a promising target for therapy.
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Affiliation(s)
| | | | | | - Arja Pasternack
- Department of Bacteriology and Immunology, Haartman Institute, University of Helsinki, Helsinki, Finland; and
| | | | | | | | - Willem M H Hoogaars
- Department of Human Movement Sciences, Faculty of Behavior and Movement Sciences, Vrije Universiteit Amsterdam, MOVE Research Institute, Amsterdam, The Netherlands
| | - Peter Ten Dijke
- Molecular Cell Biology and Cancer Genomics Centre Netherlands at the Leiden University Medical Center, Leiden, The Netherlands
| | | | | | - Olli Ritvos
- Department of Bacteriology and Immunology, Haartman Institute, University of Helsinki, Helsinki, Finland; and
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Hulmi JJ, Oliveira BM, Silvennoinen M, Hoogaars WMH, Pasternack A, Kainulainen H, Ritvos O. Exercise restores decreased physical activity levels and increases markers of autophagy and oxidative capacity in myostatin/activin-blocked mdx mice. Am J Physiol Endocrinol Metab 2013; 305:E171-82. [PMID: 23695214 DOI: 10.1152/ajpendo.00065.2013] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The importance of adequate levels of muscle size and function and physical activity is widely recognized. Myostatin/activin blocking increases skeletal muscle mass but may decrease muscle oxidative capacity and can thus be hypothesized to affect voluntary physical activity. Soluble activin receptor IIB (sActRIIB-Fc) was produced to block myostatin/activins. Modestly dystrophic mdx mice were injected with sActRIIB-Fc or PBS with or without voluntary wheel running exercise for 7 wk. Healthy mice served as controls. Running for 7 wk attenuated the sActRIIB-Fc-induced increase in body mass by decreasing fat mass. Running also enhanced/restored the markers of muscle oxidative capacity and autophagy in mdx mice to or above the levels of healthy mice. Voluntary running activity was decreased by sActRIIB-Fc during the first 3-4 wk correlating with increased body mass. Home cage physical activity of mice, quantified from the force plate signal, was decreased by sActRIIB-Fc the whole 7-wk treatment in sedentary mice. To understand what happens during the first weeks after sActRIIB-Fc administration, when mice are less active, healthy mice were injected with sActRIIB-Fc or PBS for 2 wk. During the sActRIIB-Fc-induced rapid 2-wk muscle growth period, oxidative capacity and autophagy were reduced, which may possibly explain the decreased running activity. These results show that increased muscle size and decreased markers of oxidative capacity and autophagy during the first weeks of myostatin/activin blocking are associated with decreased voluntary activity levels. Voluntary exercise in dystrophic mice enhances the markers of oxidative capacity and autophagy to or above the levels of healthy mice.
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Affiliation(s)
- Juha J Hulmi
- Department of Biology of Physical Activity, Neuromuscular Research Center, University of Jyväskylä, Finland.
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8
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Shi S, Cai J, de Gorter DJJ, Sanchez-Duffhues G, Kemaladewi DU, Hoogaars WMH, Aartsma-Rus A, ’t Hoen PAC, ten Dijke P. Antisense-oligonucleotide mediated exon skipping in activin-receptor-like kinase 2: inhibiting the receptor that is overactive in fibrodysplasia ossificans progressiva. PLoS One 2013; 8:e69096. [PMID: 23861958 PMCID: PMC3701692 DOI: 10.1371/journal.pone.0069096] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2013] [Accepted: 06/04/2013] [Indexed: 12/13/2022] Open
Abstract
Fibrodysplasia ossificans progressiva (FOP) is a rare heritable disease characterized by progressive heterotopic ossification of connective tissues, for which there is presently no definite treatment. A recurrent activating mutation (c.617G→A; R206H) of activin receptor-like kinase 2 (ACVR1/ALK2), a BMP type I receptor, has been shown as the main cause of FOP. This mutation constitutively activates the BMP signaling pathway and initiates the formation of heterotopic bone. In this study, we have designed antisense oligonucleotides (AONs) to knockdown mouse ALK2 expression by means of exon skipping. The ALK2 AON could induce exon skipping in cells, which was accompanied by decreased ALK2 mRNA levels and impaired BMP signaling. In addition, the ALK2 AON potentiated muscle differentiation and repressed BMP6-induced osteoblast differentiation. Our results therefore provide a potential therapeutic approach for the treatment of FOP disease by reducing the excessive ALK2 activity in FOP patients.
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Affiliation(s)
- SongTing Shi
- Department of Molecular Cell Biology, Cancer Genomics Centre Netherlands and Centre for Biomedical Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Jie Cai
- Department of Molecular Cell Biology, Cancer Genomics Centre Netherlands and Centre for Biomedical Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - David J. J. de Gorter
- Department of Molecular Cell Biology, Cancer Genomics Centre Netherlands and Centre for Biomedical Genetics, Leiden University Medical Center, Leiden, The Netherlands
- Institute for Molecular Cell Biology, University of Münster, Münster, Germany
| | - Gonzalo Sanchez-Duffhues
- Department of Molecular Cell Biology, Cancer Genomics Centre Netherlands and Centre for Biomedical Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Dwi U. Kemaladewi
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Willem M. H. Hoogaars
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Annemieke Aartsma-Rus
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Peter A. C. ’t Hoen
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Peter ten Dijke
- Department of Molecular Cell Biology, Cancer Genomics Centre Netherlands and Centre for Biomedical Genetics, Leiden University Medical Center, Leiden, The Netherlands
- * E-mail:
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Hulmi JJ, Oliveira BM, Silvennoinen M, Hoogaars WMH, Ma H, Pierre P, Pasternack A, Kainulainen H, Ritvos O. Muscle protein synthesis, mTORC1/MAPK/Hippo signaling, and capillary density are altered by blocking of myostatin and activins. Am J Physiol Endocrinol Metab 2013; 304:E41-50. [PMID: 23115080 DOI: 10.1152/ajpendo.00389.2012] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Loss of muscle mass and function occurs in various diseases. Myostatin blocking can attenuate muscle loss, but downstream signaling is not well known. Therefore, to elucidate associated signaling pathways, we used the soluble activin receptor IIb (sActRIIB-Fc) to block myostatin and activins in mice. Within 2 wk, the treatment rapidly increased muscle size as expected but decreased capillary density per area. sActRIIB-Fc increased muscle protein synthesis 1-2 days after the treatment correlating with enhanced mTORC1 signaling (phosphorylated rpS6 and S6K1, r = 0.8). Concurrently, increased REDD1 and eIF2Bε protein contents and phosphorylation of 4E-BP1 and AMPK was observed. In contrast, proangiogenic MAPK signaling and VEGF-A protein decreased. Hippo signaling has been characterized recently as a regulator of organ size and an important regulator of myogenesis in vitro. The phosphorylation of YAP (Yes-associated protein), a readout of activated Hippo signaling, increased after short- and longer-term myostatin and activin blocking and in exercised muscle. Moreover, dystrophic mdx mice had elevated phosphorylated and especially total YAP protein content. These results show that the blocking of myostatin and activins induce rapid skeletal muscle growth. This is associated with increased protein synthesis and mTORC1 signaling but decreased capillary density and proangiogenic signaling. It is also shown for the first time that Hippo signaling is activated in skeletal muscle after myostatin blocking and exercise and also in dystrophic muscle. This suggests that Hippo signaling may have a role in skeletal muscle in various circumstances.
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Affiliation(s)
- Juha J Hulmi
- Department of Biology of Physical Activity, Neuromuscular Research Center, University of Jyväskylä, Jyväskylä, Finland.
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Hoogaars WMH, Mouisel E, Pasternack A, Hulmi JJ, Relizani K, Schuelke M, Schirwis E, Garcia L, Ritvos O, Ferry A, 't Hoen PA, Amthor H. Combined effect of AAV-U7-induced dystrophin exon skipping and soluble activin Type IIB receptor in mdx mice. Hum Gene Ther 2012; 23:1269-79. [PMID: 22894762 DOI: 10.1089/hum.2012.056] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Adeno-associated virus (AAV)-U7-mediated skipping of dystrophin-exon-23 restores dystrophin expression and muscle function in the mdx mouse model of Duchenne muscular dystrophy. Soluble activin receptor IIB (sActRIIB-Fc) inhibits signaling of myostatin and homologous molecules and increases muscle mass and function of wild-type and mdx mice. We hypothesized that combined treatment with AAV-U7 and sActRIIB-Fc may synergistically improve mdx muscle function. Bioactivity of sActRIIB-Fc on skeletal muscle was first demonstrated in wild-type mice. In mdx mice we show that AAV-U7-mediated dystrophin restoration improved specific muscle force and resistance to eccentric contractions when applied alone. Treatment of mdx mice with sActRIIB-Fc increased body weight, muscle mass and myofiber size, but had little effect on muscle function. Combined treatment stimulated muscle growth comparable to the effect of sActRIIB-Fc alone and dystrophin rescue was similar to AAV-U7 alone. Moreover, combined treatment improved maximal tetanic force and the resistance to eccentric contraction to similar extent as AAV-U7 alone. In conclusion, combination of dystrophin exon skipping with sActRIIB-Fc brings together benefits of each treatment; however, we failed to evidence a clear synergistic effect on mdx muscle function.
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Affiliation(s)
- Willem M H Hoogaars
- Leiden University Medical Center (LUMC), Department of Human Genetics, 2333 ZC Leiden, The Netherlands
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Kemaladewi DU, Hoogaars WMH, van Heiningen SH, Terlouw S, de Gorter DJJ, den Dunnen JT, van Ommen GJB, Aartsma-Rus A, ten Dijke P, 't Hoen PAC. Dual exon skipping in myostatin and dystrophin for Duchenne muscular dystrophy. BMC Med Genomics 2011; 4:36. [PMID: 21507246 PMCID: PMC3107769 DOI: 10.1186/1755-8794-4-36] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2010] [Accepted: 04/20/2011] [Indexed: 12/26/2022] Open
Abstract
Background Myostatin is a potent muscle growth inhibitor that belongs to the Transforming Growth Factor-β (TGF-β) family. Mutations leading to non functional myostatin have been associated with hypermuscularity in several organisms. By contrast, Duchenne muscular dystrophy (DMD) is characterized by a loss of muscle fibers and impaired regeneration. In this study, we aim to knockdown myostatin by means of exon skipping, a technique which has been successfully applied to reframe the genetic defect of dystrophin gene in DMD patients. Methods We targeted myostatin exon 2 using antisense oligonucleotides (AON) in healthy and DMD-derived myotubes cultures. We assessed the exon skipping level, transcriptional expression of myostatin and its target genes, and combined myostatin and several dystrophin AONs. These AONs were also applied in the mdx mice models via intramuscular injections. Results Myostatin AON induced exon 2 skipping in cell cultures and to a lower extent in the mdx mice. It was accompanied by decrease in myostatin mRNA and enhanced MYOG and MYF5 expression. Furthermore, combination of myostatin and dystrophin AONs induced simultaneous skipping of both genes. Conclusions We conclude that two AONs can be used to target two different genes, MSTN and DMD, in a straightforward manner. Targeting multiple ligands of TGF-beta family will be more promising as adjuvant therapies for DMD.
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Affiliation(s)
- Dwi U Kemaladewi
- Center for Human and Clinical Genetics, Leiden University Medical Center, Postzone S4-P, PO Box 9600, Leiden, 2300RC, the Netherlands
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12
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Shi S, Hoogaars WMH, de Gorter DJJ, van Heiningen SH, Lin HY, Hong CC, Kemaladewi DU, Aartsma-Rus A, ten Dijke P, 't Hoen PAC. BMP antagonists enhance myogenic differentiation and ameliorate the dystrophic phenotype in a DMD mouse model. Neurobiol Dis 2010; 41:353-60. [PMID: 20940052 DOI: 10.1016/j.nbd.2010.10.003] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2010] [Revised: 09/23/2010] [Accepted: 10/01/2010] [Indexed: 12/29/2022] Open
Abstract
Duchenne Muscular Dystrophy (DMD) is an X-linked lethal muscle wasting disease characterized by muscle fiber degeneration and necrosis. The progressive pathology of DMD can be explained by an insufficient regenerative response resulting in fibrosis and adipose tissue formation. BMPs are known to inhibit myogenic differentiation and in a previous study we found an increased expression of a BMP family member BMP4 in DMD myoblasts. The aim of the current study was therefore to investigate whether inhibition of BMP signaling could be beneficial for myoblast differentiation and muscle regeneration processes in a DMD context. All tested BMP inhibitors, Noggin, dorsomorphin and LDN-193189, were able to accelerate and enhance myogenic differentiation. However, dorsomorphin repressed both BMP and TGFβ signaling and was found to be toxic to primary myoblast cell cultures. In contrast, Noggin was found to be a potent and selective BMP inhibitor and was therefore tested in vivo in a DMD mouse model. Local adenoviral-mediated overexpression of Noggin in muscle resulted in an increased expression of the myogenic regulatory genes Myog and Myod1 and improved muscle histology. In conclusion, our results suggest that repression of BMP signaling may constitute an attractive adjunctive therapy for DMD patients.
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Affiliation(s)
- SongTing Shi
- Department of Molecular Cell Biology and Centre for Biomedical Genetics, Leiden, The Netherlands
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13
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Ruijter JM, Ramakers C, Hoogaars WMH, Karlen Y, Bakker O, van den Hoff MJB, Moorman AFM. Amplification efficiency: linking baseline and bias in the analysis of quantitative PCR data. Nucleic Acids Res 2009; 37:e45. [PMID: 19237396 PMCID: PMC2665230 DOI: 10.1093/nar/gkp045] [Citation(s) in RCA: 2125] [Impact Index Per Article: 141.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2008] [Revised: 01/15/2009] [Accepted: 01/15/2009] [Indexed: 11/13/2022] Open
Abstract
Despite the central role of quantitative PCR (qPCR) in the quantification of mRNA transcripts, most analyses of qPCR data are still delegated to the software that comes with the qPCR apparatus. This is especially true for the handling of the fluorescence baseline. This article shows that baseline estimation errors are directly reflected in the observed PCR efficiency values and are thus propagated exponentially in the estimated starting concentrations as well as 'fold-difference' results. Because of the unknown origin and kinetics of the baseline fluorescence, the fluorescence values monitored in the initial cycles of the PCR reaction cannot be used to estimate a useful baseline value. An algorithm that estimates the baseline by reconstructing the log-linear phase downward from the early plateau phase of the PCR reaction was developed and shown to lead to very reproducible PCR efficiency values. PCR efficiency values were determined per sample by fitting a regression line to a subset of data points in the log-linear phase. The variability, as well as the bias, in qPCR results was significantly reduced when the mean of these PCR efficiencies per amplicon was used in the calculation of an estimate of the starting concentration per sample.
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Affiliation(s)
- J M Ruijter
- Heart Failure Research Center, Academic Medical Center, University of Amsterdam, The Netherlands.
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14
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Remme CA, Verkerk AO, Hoogaars WMH, Aanhaanen WTJ, Scicluna BP, Annink C, van den Hoff MJB, Wilde AAM, van Veen TAB, Veldkamp MW, de Bakker JMT, Christoffels VM, Bezzina CR. The cardiac sodium channel displays differential distribution in the conduction system and transmural heterogeneity in the murine ventricular myocardium. Basic Res Cardiol 2009; 104:511-22. [PMID: 19255801 PMCID: PMC2722719 DOI: 10.1007/s00395-009-0012-8] [Citation(s) in RCA: 91] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/24/2008] [Revised: 01/30/2009] [Accepted: 02/03/2009] [Indexed: 12/15/2022]
Abstract
Cardiac sodium channels are responsible for conduction in the normal and diseased heart. We aimed to investigate regional and transmural distribution of sodium channel expression and function in the myocardium. Sodium channel Scn5a mRNA and Na(v)1.5 protein distribution was investigated in adult and embryonic mouse heart through immunohistochemistry and in situ hybridization. Functional sodium channel availability in subepicardial and subendocardial myocytes was assessed using patch-clamp technique. Adult and embryonic (ED14.5) mouse heart sections showed low expression of Na(v)1.5 in the HCN4-positive sinoatrial and atrioventricular nodes. In contrast, high expression levels of Na(v)1.5 were observed in the HCN4-positive and Cx43-negative AV or His bundle, bundle branches and Purkinje fibers. In both ventricles, a transmural gradient was observed, with a low Na(v)1.5 labeling intensity in the subepicardium as compared to the subendocardium. Similar Scn5a mRNA expression patterns were observed on in situ hybridization of embryonic and adult tissue. Maximal action potential upstroke velocity was significantly lower in subepicardial myocytes (mean +/- SEM 309 +/- 32 V/s; n = 14) compared to subendocardial myocytes (394 +/- 32 V/s; n = 11; P < 0.05), indicating decreased sodium channel availability in subepicardium compared to subendocardium. Scn5a and Na(v)1.5 show heterogeneous distribution patterns within the cardiac conduction system and across the ventricular wall. This differential distribution of the cardiac sodium channel may have profound consequences for conduction disease phenotypes and arrhythmogenesis in the setting of sodium channel disease.
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Affiliation(s)
- C A Remme
- Heart Failure Research Center, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
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15
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Mommersteeg MTM, Hoogaars WMH, Prall OWJ, de Gier-de Vries C, Wiese C, Clout DEW, Papaioannou VE, Brown NA, Harvey RP, Moorman AFM, Christoffels VM. Molecular pathway for the localized formation of the sinoatrial node. Circ Res 2007; 100:354-62. [PMID: 17234970 DOI: 10.1161/01.res.0000258019.74591.b3] [Citation(s) in RCA: 254] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The sinoatrial node, which resides at the junction of the right atrium and the superior caval vein, contains specialized myocardial cells that initiate the heart beat. Despite this fundamental role in heart function, the embryonic origin and mechanisms of localized formation of the sinoatrial node have not been defined. Here we show that subsequent to the formation of the Nkx2-5-positive heart tube, cells bordering the inflow tract of the heart tube give rise to the Nkx2-5-negative myocardial cells of the sinoatrial node and the sinus horns. Using genetic models, we show that as the myocardium of the heart tube matures, Nkx2-5 suppresses pacemaker channel gene Hcn4 and T-box transcription factor gene Tbx3, thereby enforcing a progressive confinement of their expression to the forming Nkx2-5-negative sinoatrial node and sinus horns. Thus, Nkx2-5 is essential for establishing a gene expression border between the atrium and sinoatrial node. Tbx3 was found to suppress chamber differentiation, providing an additional mechanism by which the Tbx3-positive sinoatrial node is shielded from differentiating into atrial myocardium. Pitx2c-deficient fetuses form sinoatrial nodes with indistinguishable molecular signatures at both the right and left sinuatrial junction, indicating that Pitx2c functions within the left/right pathway to suppress a default program for sinuatrial node formation on the left. Our molecular pathway provides a mechanism for how pacemaker activity becomes progressively relegated to the most recently added components of the venous pole of the heart and, ultimately, to the junction of the right atrium and superior caval vein.
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Affiliation(s)
- Mathilda T M Mommersteeg
- Center for Heart Failure Research, Academic Medical Centre, Meibergdreef 15, 1105 AZ, Amsterdam, The Netherlands
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Streefkerk JO, Hoogaars WMH, Christoffels VM, Sand C, Pfaffendorf M, Peters SLM, Van Zwieten PA. Vasopressin-induced vasoconstriction is dependent on MAPKerk1/2 phosphorylation. Fundam Clin Pharmacol 2004; 18:45-50. [PMID: 14748753 DOI: 10.1046/j.1472-8206.2003.00221.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
To investigate the involvement of the mitogen-activated protein kinase (MAPK) family of extracellular signal-regulated kinase (ERK) 1 and 2 (MAPKerk1/2) in the vasopressin-mediated vasoconstriction in the rat aorta. Vasopressin-induced vasoconstriction was measured in isolated rat thoracic aortae in the presence or absence of MAPKerk1/2 kinase (MKKmek1/2) inhibitors. Thereafter the MAPKerk1/2 phosphorylation in the rat aorta was quantified using Western blot analysis. Vasopressin (1-300 nm) induced a concentration-dependent vasoconstriction, which could be inhibited concentration dependently by the selective MKKmek1/2 inhibitors, PD 98059 (10 and 100 microm) and U 0126 (10 and 100 microm). Western blot analysis revealed a 2.7 +/- 0.6-fold increase in the MAPKerk1/2 phosphorylation induced by vasopressin (300 nm). This phosphorylation could be dose dependently prevented by both PD 98059 (100 microm) and U 0126 (10 and 100 microm). These results indicate that vasoconstriction induced by vasopressin is partly regulated by the MAPKerk1/2 pathway.
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Affiliation(s)
- Jörn O Streefkerk
- The Department of Pharmacotherapy, Academic Medical Centre, University of Amsterdam, Meibergdreef 15, 1105 AZ Amsterdam, The Netherlands.
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Hoogaars WMH, Tessari A, Moorman AFM, de Boer PAJ, Hagoort J, Soufan AT, Campione M, Christoffels VM. The transcriptional repressor Tbx3 delineates the developing central conduction system of the heart. Cardiovasc Res 2004; 62:489-99. [PMID: 15158141 DOI: 10.1016/j.cardiores.2004.01.030] [Citation(s) in RCA: 234] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/14/2003] [Revised: 01/27/2004] [Accepted: 01/28/2004] [Indexed: 10/26/2022] Open
Abstract
OBJECTIVE The molecular mechanisms that regulate the formation of the conduction system are poorly understood. We studied the developmental expression pattern and functional aspects of the T-box transcription factor Tbx3, a novel marker for the murine central conduction system (CCS). METHODS The patterns of expression of Tbx3, and of Cx40, Cx43, and Nppa, which are markers for atrial and ventricular chamber-type myocardium in the developing heart, were analyzed in mice by in situ hybridization and three-dimensional reconstruction analysis. The function of Tbx3 in regulating Nppa and Cx40 promoter activity was studied in vitro. RESULTS In the formed heart, Tbx3 is expressed in the sinoatrial node (SAN), atrioventricular node (AVN), bundle and proximal bundle branches (BBs), as well as the internodal regions and the atrioventricular region. Throughout cardiac development, Tbx3 is expressed in an uninterrupted myocardial domain that extends from the sinoatrial node to the atrioventricular region. This expression domain is present in the looping heart tube from E8.5 onwards. Expression of the chamber-type myocardial markers is specifically absent from the Tbx3 expression domain. Tbx3 is able to repress Nppa and Cx40 promoter activity and abolish the synergistic activation of the Nppa promoter by Tbx5 and Nkx2.5. CONCLUSION We identified the T-box transcription factor Tbx3 as a novel and accurate marker for the central conduction system. Our analysis implicates a role for Tbx3 in repressing a chamber-specific program of gene expression in regions from which the components of the central conduction system are subsequently formed.
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Affiliation(s)
- Willem M H Hoogaars
- Experimental and Molecular Cardiology Group, AMC, University of Amsterdam, Amsterdam, The Netherlands
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18
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Christoffels VM, Hoogaars WMH, Tessari A, Clout DEW, Moorman AFM, Campione M. T-box transcription factor Tbx2 represses differentiation and formation of the cardiac chambers. Dev Dyn 2004; 229:763-70. [PMID: 15042700 DOI: 10.1002/dvdy.10487] [Citation(s) in RCA: 187] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Specific regions of the embryonic heart tube differentiate into atrial and ventricular chamber myocardium, whereas the inflow tract, atrioventricular canal, inner curvatures, and outflow tract do not. These regions express Tbx2, a transcriptional repressor. Here, we tested its role in chamber formation. The temporal and spatial pattern of Tbx2 mRNA and protein expression in mouse hearts was found to be complementary to that of chamber myocardium-specific genes Nppa, Cx40, Cx43, and Chisel, and was conserved in human. In vitro, Tbx2 repressed the activity of regulatory fragments of Cx40, Cx43, and Nppa. Hearts of transgenic embryos that expressed Tbx2 in the prechamber myocardium completely failed to form chambers and to express the chamber myocardium-specific genes Nppa, Cx40, and Chisel, whereas other cardiac genes were normally expressed. These findings provide the first evidence that Tbx2 is a determinant in the local repression of chamber-specific gene expression and chamber differentiation.
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Affiliation(s)
- Vincent M Christoffels
- Experimental and Molecular Cardiology Group, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
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