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Yu Y, Su Y, Wang G, Lan M, Liu J, Garcia Martin R, Brandao BB, Lino M, Li L, Liu C, Kahn CR, Meng Q. Reciprocal communication between FAPs and muscle cells via distinct extracellular vesicle miRNAs in muscle regeneration. Proc Natl Acad Sci U S A 2024; 121:e2316544121. [PMID: 38442155 PMCID: PMC10945765 DOI: 10.1073/pnas.2316544121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2023] [Accepted: 02/06/2024] [Indexed: 03/07/2024] Open
Abstract
Muscle regeneration is a complex process relying on precise teamwork between multiple cell types, including muscle stem cells (MuSCs) and fibroadipogenic progenitors (FAPs). FAPs are also the main source of intramuscular adipose tissue (IMAT). Muscles without FAPs exhibit decreased IMAT infiltration but also deficient muscle regeneration, indicating the importance of FAPs in the repair process. Here, we demonstrate the presence of bidirectional crosstalk between FAPs and MuSCs via their secretion of extracellular vesicles (EVs) containing distinct clusters of miRNAs that is crucial for normal muscle regeneration. Thus, after acute muscle injury, there is activation of FAPs leading to a transient rise in IMAT. These FAPs also release EVs enriched with a selected group of miRNAs, a number of which come from an imprinted region on chromosome 12. The most abundant of these is miR-127-3p, which targets the sphingosine-1-phosphate receptor S1pr3 and activates myogenesis. Indeed, intramuscular injection of EVs from immortalized FAPs speeds regeneration of injured muscle. In late stages of muscle repair, in a feedback loop, MuSCs and their derived myoblasts/myotubes secrete EVs enriched in miR-206-3p and miR-27a/b-3p. The miRNAs repress FAP adipogenesis, allowing full muscle regeneration. Together, the reciprocal communication between FAPs and muscle cells via miRNAs in their secreted EVs plays a critical role in limiting IMAT infiltration while stimulating muscle regeneration, hence providing an important mechanism for skeletal muscle repair and homeostasis.
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Affiliation(s)
- Yingying Yu
- State Key Laboratory of Animal Biotech Breeding, College of Biological Sciences, Department of Genetics and Molecular biology, China Agricultural University, Beijing100193, China
- Section on Integrative Physiology and Metabolism, Joslin Diabetes Center, Department of Medicine, Harvard Medical School, Boston, MA02215
| | - Yang Su
- State Key Laboratory of Animal Biotech Breeding, College of Biological Sciences, Department of Genetics and Molecular biology, China Agricultural University, Beijing100193, China
- Department of Cell Biology, Third Military Medical University, Chongqing400038, China
| | - Guoxiao Wang
- Section on Integrative Physiology and Metabolism, Joslin Diabetes Center, Department of Medicine, Harvard Medical School, Boston, MA02215
| | - Miaomiao Lan
- State Key Laboratory of Animal Biotech Breeding, College of Biological Sciences, Department of Genetics and Molecular biology, China Agricultural University, Beijing100193, China
| | - Jin Liu
- State Key Laboratory of Animal Biotech Breeding, College of Biological Sciences, Department of Genetics and Molecular biology, China Agricultural University, Beijing100193, China
| | - Ruben Garcia Martin
- Section on Integrative Physiology and Metabolism, Joslin Diabetes Center, Department of Medicine, Harvard Medical School, Boston, MA02215
| | - Bruna Brasil Brandao
- Section on Integrative Physiology and Metabolism, Joslin Diabetes Center, Department of Medicine, Harvard Medical School, Boston, MA02215
| | - Marsel Lino
- Section on Integrative Physiology and Metabolism, Joslin Diabetes Center, Department of Medicine, Harvard Medical School, Boston, MA02215
| | - Lei Li
- State Key Laboratory of Animal Biotech Breeding, College of Biological Sciences, Department of Genetics and Molecular biology, China Agricultural University, Beijing100193, China
| | - Chang Liu
- State Key Laboratory of Animal Biotech Breeding, College of Biological Sciences, Department of Genetics and Molecular biology, China Agricultural University, Beijing100193, China
| | - C. Ronald Kahn
- Section on Integrative Physiology and Metabolism, Joslin Diabetes Center, Department of Medicine, Harvard Medical School, Boston, MA02215
| | - Qingyong Meng
- State Key Laboratory of Animal Biotech Breeding, College of Biological Sciences, Department of Genetics and Molecular biology, China Agricultural University, Beijing100193, China
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Lee SY, Lee DY, Yun SH, Lee J, Mariano E, Park J, Choi Y, Han D, Kim JS, Hur SJ. Current technology and industrialization status of cell-cultivated meat. JOURNAL OF ANIMAL SCIENCE AND TECHNOLOGY 2024; 66:1-30. [PMID: 38618028 PMCID: PMC11007461 DOI: 10.5187/jast.2023.e107] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Revised: 10/05/2023] [Accepted: 10/09/2023] [Indexed: 04/16/2024]
Abstract
Interest and investment in cultivated meat are increasing because of the realization that it can effectively supply sufficient food resources and reduce the use of livestock. Nevertheless, accurate information on the specific technologies used for cultivated meat production and the characteristics of cultivated meat is lacking. Authorization for the use of cultivated meat is already underway in the United States, Singapore, and Israel, and other major countries are also expected to approve cultivated meat as food once the details of the intricate process of producing cultivated meat, which encompasses stages such as cell proliferation, differentiation, maturation, and assembly, is thoroughly established. The development and standardization of mass production processes and safety evaluations must precede the industrialization and use of cultivated meat as food. However, the technology for the industrialization of cultivated meat is still in its nascent stage, and the mass production process has not yet been established. The mass production process of cultivated meat may not be easy to disclose because it is related to the interests of several companies or research teams. However, the overall research flow shows that equipment development for mass production and cell acquisition, proliferation, and differentiation, as well as for three-dimensional production supports and bioreactors have not yet been completed. Therefore, additional research on the mass production process and safety of cultivated meat is essential. The consumer's trust in the cultivated meat products and production technologies recently disclosed by some companies should also be analyzed and considered for guiding future developments in this industry. Furthermore, close monitoring by academia and the government will be necessary to identify fraud in the cultivated meat industry.
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Affiliation(s)
- Seung Yun Lee
- Division of Animal Science, Division of
Applied Life Science (BK21 Four), Institute of Agriculture & Life
Science, Gyeongsang National University, Jinju 52828,
Korea
| | - Da Young Lee
- Department of Animal Science and
Technology, Chung-Ang University, Anseong 17546, Korea
| | - Seung Hyeon Yun
- Department of Animal Science and
Technology, Chung-Ang University, Anseong 17546, Korea
| | - Juhyun Lee
- Department of Animal Science and
Technology, Chung-Ang University, Anseong 17546, Korea
| | - Ermie Mariano
- Department of Animal Science and
Technology, Chung-Ang University, Anseong 17546, Korea
| | - Jinmo Park
- Department of Animal Science and
Technology, Chung-Ang University, Anseong 17546, Korea
| | - Yeongwoo Choi
- Department of Animal Science and
Technology, Chung-Ang University, Anseong 17546, Korea
| | - Dahee Han
- Department of Animal Science and
Technology, Chung-Ang University, Anseong 17546, Korea
| | - Jin Soo Kim
- Department of Animal Science and
Technology, Chung-Ang University, Anseong 17546, Korea
| | - Sun Jin Hur
- Department of Animal Science and
Technology, Chung-Ang University, Anseong 17546, Korea
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Hildyard JCW, Piercy RJ. When Size Really Matters: The Eccentricities of Dystrophin Transcription and the Hazards of Quantifying mRNA from Very Long Genes. Biomedicines 2023; 11:2082. [PMID: 37509720 PMCID: PMC10377302 DOI: 10.3390/biomedicines11072082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Revised: 07/10/2023] [Accepted: 07/14/2023] [Indexed: 07/30/2023] Open
Abstract
At 2.3 megabases in length, the dystrophin gene is enormous: transcription of a single mRNA requires approximately 16 h. Principally expressed in skeletal muscle, the dystrophin protein product protects the muscle sarcolemma against contraction-induced injury, and dystrophin deficiency results in the fatal muscle-wasting disease, Duchenne muscular dystrophy. This gene is thus of key clinical interest, and therapeutic strategies aimed at eliciting dystrophin restoration require quantitative analysis of its expression. Approaches for quantifying dystrophin at the protein level are well-established, however study at the mRNA level warrants closer scrutiny: measured expression values differ in a sequence-dependent fashion, with significant consequences for data interpretation. In this manuscript, we discuss these nuances of expression and present evidence to support a transcriptional model whereby the long transcription time is coupled to a short mature mRNA half-life, with dystrophin transcripts being predominantly nascent as a consequence. We explore the effects of such a model on cellular transcriptional dynamics and then discuss key implications for the study of dystrophin gene expression, focusing on both conventional (qPCR) and next-gen (RNAseq) approaches.
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Affiliation(s)
- John C. W. Hildyard
- Comparative Neuromuscular Disease Laboratory, Department of Clinical Science and Services, Royal Veterinary College, London NW1 0TU, UK;
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Liu C, Wu X, Vulugundam G, Gokulnath P, Li G, Xiao J. Exercise Promotes Tissue Regeneration: Mechanisms Involved and Therapeutic Scope. SPORTS MEDICINE - OPEN 2023; 9:27. [PMID: 37149504 PMCID: PMC10164224 DOI: 10.1186/s40798-023-00573-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Accepted: 04/23/2023] [Indexed: 05/08/2023]
Abstract
Exercise has well-recognized beneficial effects on the whole body. Previous studies suggest that exercise could promote tissue regeneration and repair in various organs. In this review, we have summarized the major effects of exercise on tissue regeneration primarily mediated by stem cells and progenitor cells in skeletal muscle, nervous system, and vascular system. The protective function of exercise-induced stem cell activation under pathological conditions and aging in different organs have also been discussed in detail. Moreover, we have described the primary molecular mechanisms involved in exercise-induced tissue regeneration, including the roles of growth factors, signaling pathways, oxidative stress, metabolic factors, and non-coding RNAs. We have also summarized therapeutic approaches that target crucial signaling pathways and molecules responsible for exercise-induced tissue regeneration, such as IGF1, PI3K, and microRNAs. Collectively, the comprehensive understanding of exercise-induced tissue regeneration will facilitate the discovery of novel drug targets and therapeutic strategies.
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Affiliation(s)
- Chang Liu
- Institute of Geriatrics (Shanghai University), Affiliated Nantong Hospital of Shanghai University (The Sixth People's Hospital of Nantong), School of Medicine, Shanghai University, Nantong, 226011, China
- Cardiac Regeneration and Ageing Lab, Institute of Cardiovascular Sciences, Shanghai Engineering Research Center of Organ Repair, School of Life Science, Shanghai University, Shanghai, 200444, China
| | - Xinying Wu
- Institute of Geriatrics (Shanghai University), Affiliated Nantong Hospital of Shanghai University (The Sixth People's Hospital of Nantong), School of Medicine, Shanghai University, Nantong, 226011, China
- Cardiac Regeneration and Ageing Lab, Institute of Cardiovascular Sciences, Shanghai Engineering Research Center of Organ Repair, School of Life Science, Shanghai University, Shanghai, 200444, China
| | | | - Priyanka Gokulnath
- Cardiovascular Division of the Massachusetts General Hospital and Harvard Medical School, Boston, MA, 02114, USA
| | - Guoping Li
- Cardiovascular Division of the Massachusetts General Hospital and Harvard Medical School, Boston, MA, 02114, USA.
| | - Junjie Xiao
- Institute of Geriatrics (Shanghai University), Affiliated Nantong Hospital of Shanghai University (The Sixth People's Hospital of Nantong), School of Medicine, Shanghai University, Nantong, 226011, China.
- Cardiac Regeneration and Ageing Lab, Institute of Cardiovascular Sciences, Shanghai Engineering Research Center of Organ Repair, School of Life Science, Shanghai University, Shanghai, 200444, China.
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Chen W, He Z, Li S, Wu Z, Tan J, Yang W, Li G, Pan X, Liu Y, Lyu FJ, Li W. The Effect of Tissue Stromal Vascular Fraction as Compared to Cellular Stromal Vascular Fraction to Treat Anal Sphincter Incontinence. BIOENGINEERING (BASEL, SWITZERLAND) 2022; 10:bioengineering10010032. [PMID: 36671604 PMCID: PMC9854502 DOI: 10.3390/bioengineering10010032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 11/30/2022] [Accepted: 12/12/2022] [Indexed: 12/28/2022]
Abstract
BACKGROUND The long-term prognosis of current treatments for anal sphincter incontinence (ASI) is poor. Here, we explored the efficacy of tissue adipose stromal vascular fraction SVF (tSVF) on ASI and compared it to that of cellular SVF (cSVF). We then investigated possible mechanisms. METHODS Rat cSVF and tSVF were isolated and labeled with DIL. One day after modeling, three groups received phosphate-buffered saline (PBS), cSVF, tSVF, respectively. The control group received nil modeling nor any treatments. The effect was assessed by function test for anal pressure and electromyography, and staining for fiber content, proliferation and differentiation at day 5 and day 10. RESULTS cSVF injection resulted in faster healing than tSVF. The cSVF group showed significant improvement on anal pressure on day 10. For the electromyography test, cSVF showed significant improvement for the frequencies on day 10, and for the peak values on both time points, while tSVF showed significant improvement for the peak values on day 10. The two SVF both alleviated fibrosis. Immunofluorescence tracing identified differentiation of some injected cells towards myosatellite cells and smooth muscle cells in both SVF groups. For all the tests, the tSVF group tends to have similar or lower effects than the cSVF group with no significant difference. CONCLUSION cSVF and tSVF are both safe and effective in treating ASI, while the effect of cSVF is slighter higher than tSVF.
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Affiliation(s)
- Wenbin Chen
- Department of Colorectal and Anal Surgery, The Second Affiliated Hospital, School of Medicine, South China University of Technology, Guangzhou 510641, China
| | - Zijian He
- Department of Colorectal and Anal Surgery, The Second Affiliated Hospital, School of Medicine, South China University of Technology, Guangzhou 510641, China
| | - Shuyu Li
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou 510641, China
| | - Zixin Wu
- Department of Colorectal and Anal Surgery, The Second Affiliated Hospital, School of Medicine, South China University of Technology, Guangzhou 510641, China
| | - Jin Tan
- The Sixth Affiliated Hospital, School of Medicine, South China University of Technology, Guangzhou 510641, China
| | - Weifeng Yang
- Department of Colorectal and Anal Surgery, The Second Affiliated Hospital, School of Medicine, South China University of Technology, Guangzhou 510641, China
| | - Guanwei Li
- Department of Colorectal and Anal Surgery, The Second Affiliated Hospital, School of Medicine, South China University of Technology, Guangzhou 510641, China
| | - Xiaoling Pan
- The Sixth Affiliated Hospital, School of Medicine, South China University of Technology, Guangzhou 510641, China
| | - Yuying Liu
- The Sixth Affiliated Hospital, School of Medicine, South China University of Technology, Guangzhou 510641, China
| | - Feng-Juan Lyu
- The Sixth Affiliated Hospital, School of Medicine, South China University of Technology, Guangzhou 510641, China
- Correspondence: (F.-J.L.); (W.L.)
| | - Wanglin Li
- Department of Colorectal and Anal Surgery, The Second Affiliated Hospital, School of Medicine, South China University of Technology, Guangzhou 510641, China
- Correspondence: (F.-J.L.); (W.L.)
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6
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Brook MS, Wilkinson DJ, Tarum J, Mitchell KW, Lund JL, Phillips BE, Szewczyk NJ, Kadi F, Greenhaff PL, Smith K, Atherton PJ. Neither myonuclear accretion nor a myonuclear domain size ceiling is a feature of the attenuated hypertrophic potential of aged human skeletal muscle. GeroScience 2022; 45:451-462. [PMID: 36083436 PMCID: PMC9886697 DOI: 10.1007/s11357-022-00651-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Accepted: 08/25/2022] [Indexed: 02/03/2023] Open
Abstract
Ageing limits growth capacity of skeletal muscle (e.g. in response to resistance exercise), but the role of satellite cell (SC) function in driving this phenomenon is poorly defined. Younger (Y) (~ 23 years) and older (O) men (~ 69 years) (normal-weight BMI) underwent 6 weeks of unilateral resistance exercise training (RET). Muscle biopsies were taken at baseline and after 3-/6-week training. We determined muscle size by fibre CSA (and type), SC number, myonuclei counts and DNA synthesis (via D2O ingestion). At baseline, there were no significant differences in fibre areas between Y and O. RET increased type I fibre area in Y from baseline at both 3 weeks and 6 weeks (baseline: 4509 ± 534 µm2, 3 weeks; 5497 ± 510 µm2 P < 0.05, 6 weeks; 5402 ± 352 µm2 P < 0.05), whilst O increased from baseline at 6 weeks only (baseline 5120 ± 403 µm2, 3 weeks; 5606 ± 620 µm2, 6 weeks; 6017 ± 482 µm2 P < 0.05). However, type II fibre area increased from baseline in Y at both 3 weeks and 6 weeks (baseline: 4949 ± 459 µm2, 3 weeks; 6145 ± 484 µm2 (P < 0.01), 6 weeks; 5992 ± 491 µm2 (P < 0.01), whilst O showed no change (baseline 5210 ± 410 µm2, 3 weeks; 5356 ± 535 µm2 (P = 0.9), 6 weeks; 5857 ± 478 µm2 (P = 0.1). At baseline, there were no differences in fibre myonuclei number between Y and O. RET increased type I fibre myonuclei number from baseline in both Y and O at 3 weeks and 6 weeks with RET (younger: baseline 2.47 ± 0.16, 3 weeks; 3.19 ± 0.16 (P < 0.001), 6 weeks; 3.70 ± 0.29 (P < 0.0001); older: baseline 2.29 ± 0.09, 3 weeks; 3.01 ± 0.09 (P < 0.001), 6 weeks; 3.65 ± 0.18 (P < 0.0001)). Similarly, type II fibre myonuclei number increased from baseline in both Y and O at 3 weeks and 6 weeks (younger: baseline 2.49 ± 0.14, 3 weeks; 3.31 ± 0.21 (P < 0.001), 6 weeks; 3.86 ± 0.29 (P < 0.0001); older: baseline 2.43 ± 0.12, 3 weeks; 3.37 ± 0.12 (P < 0.001), 6 weeks; 3.81 ± 0.15 (P < 0.0001)). DNA synthesis rates %.d-1 exhibited a main effect of training but no age discrimination. Declines in myonuclei addition do not underlie impaired muscle growth capacity in older humans, supporting ribosomal and proteostasis impairments as we have previously reported.
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Affiliation(s)
- Matthew S. Brook
- MRC-Versus Arthritis Centre for Musculoskeletal Ageing Research and NIHR Nottingham BRC, Centre of Metabolism, Ageing and Physiology (COMAP), School of Medicine, University of Nottingham, Derby, UK ,School of Life Sciences, University of Nottingham, Nottingham, UK
| | - Daniel J. Wilkinson
- MRC-Versus Arthritis Centre for Musculoskeletal Ageing Research and NIHR Nottingham BRC, Centre of Metabolism, Ageing and Physiology (COMAP), School of Medicine, University of Nottingham, Derby, UK
| | - Janelle Tarum
- School of Health Sciences, Örebro University, Örebro, Sweden
| | - Kyle W. Mitchell
- MRC-Versus Arthritis Centre for Musculoskeletal Ageing Research and NIHR Nottingham BRC, Centre of Metabolism, Ageing and Physiology (COMAP), School of Medicine, University of Nottingham, Derby, UK
| | - Jonathan L. Lund
- MRC-Versus Arthritis Centre for Musculoskeletal Ageing Research and NIHR Nottingham BRC, Centre of Metabolism, Ageing and Physiology (COMAP), School of Medicine, University of Nottingham, Derby, UK
| | - Bethan E. Phillips
- MRC-Versus Arthritis Centre for Musculoskeletal Ageing Research and NIHR Nottingham BRC, Centre of Metabolism, Ageing and Physiology (COMAP), School of Medicine, University of Nottingham, Derby, UK
| | - Nathaniel J. Szewczyk
- MRC-Versus Arthritis Centre for Musculoskeletal Ageing Research and NIHR Nottingham BRC, Centre of Metabolism, Ageing and Physiology (COMAP), School of Medicine, University of Nottingham, Derby, UK
| | - Fawzi Kadi
- School of Health Sciences, Örebro University, Örebro, Sweden
| | - Paul L. Greenhaff
- MRC-Versus Arthritis Centre for Musculoskeletal Ageing Research and NIHR Nottingham BRC, Centre of Metabolism, Ageing and Physiology (COMAP), School of Medicine, University of Nottingham, Derby, UK ,School of Life Sciences, University of Nottingham, Nottingham, UK
| | - Ken Smith
- MRC-Versus Arthritis Centre for Musculoskeletal Ageing Research and NIHR Nottingham BRC, Centre of Metabolism, Ageing and Physiology (COMAP), School of Medicine, University of Nottingham, Derby, UK
| | - Philip J. Atherton
- MRC-Versus Arthritis Centre for Musculoskeletal Ageing Research and NIHR Nottingham BRC, Centre of Metabolism, Ageing and Physiology (COMAP), School of Medicine, University of Nottingham, Derby, UK
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Tollance A, Koenig S, Liaudet N, Frieden M. Activation and Migration of Human Skeletal Muscle Stem Cells In Vitro Differently Rely on Calcium Signals. Cells 2022; 11:cells11101689. [PMID: 35626726 PMCID: PMC9140175 DOI: 10.3390/cells11101689] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Revised: 05/11/2022] [Accepted: 05/17/2022] [Indexed: 02/04/2023] Open
Abstract
Muscle regeneration is essential for proper muscle homeostasis and relies primarily on muscle stem cells (MuSC). MuSC are maintained quiescent in their niche and can be activated following muscle injury. Using an in vitro model of primary human quiescent MuSC (called reserve cells, RC), we analyzed their Ca2+ response following their activation by fetal calf serum and assessed the role of Ca2+ in the processes of RC activation and migration. The results showed that RC displayed a high response heterogeneity in a cell-dependent manner following serum stimulation. Most of these responses relied on inositol 1,4,5-trisphosphate (IP3)-dependent Ca2+ release associated with Ca2+ influx, partly due to store-operated calcium entry. Our study further found that blocking the IP3 production, Ca2+ influx, or both did not prevent the activation of RC. Intra- or extracellular Ca2+ chelation did not impede RC activation. However, their migration potential depended on Ca2+ responses displayed upon stimulation, and Ca2+ blockers inhibited their movement. We conclude that the two major steps of muscle regeneration, namely the activation and migration of MuSC, differently rely on Ca2+ signals.
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Affiliation(s)
- Axel Tollance
- Department of Cell Physiology and Metabolism, University of Geneva Medical Center, 1211 Geneva, Switzerland;
| | - Stéphane Koenig
- Department of Cell Physiology and Metabolism, University of Geneva Medical Center, 1211 Geneva, Switzerland;
- Correspondence: (S.K.); (M.F.)
| | - Nicolas Liaudet
- Bioimaging Core Facility, University of Geneva Medical Center, 1211 Geneva, Switzerland;
| | - Maud Frieden
- Department of Cell Physiology and Metabolism, University of Geneva Medical Center, 1211 Geneva, Switzerland;
- Correspondence: (S.K.); (M.F.)
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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] [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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9
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Sheets K, Overbey J, Ksajikian A, Bovid K, Kenter K, Li Y. The pathophysiology and treatment of musculoskeletal fibrosis. J Cell Biochem 2022; 123:843-851. [DOI: 10.1002/jcb.30217] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Revised: 12/20/2021] [Accepted: 01/07/2022] [Indexed: 12/19/2022]
Affiliation(s)
- Kelsey Sheets
- Department of Orthopaedic Surgery, Homer Stryker MD School of Medicine Western Michigan University Kalamazoo Michigan USA
| | - Juliana Overbey
- BioMedical Engineering, Department of Orthopaedic Surgery, WMed, Homer Stryker MD School of Medicine Western Michigan University Kalamazoo Michigan USA
| | - Andre Ksajikian
- BioMedical Engineering, Department of Orthopaedic Surgery, WMed, Homer Stryker MD School of Medicine Western Michigan University Kalamazoo Michigan USA
| | - Karen Bovid
- Department of Orthopaedic Surgery, Homer Stryker MD School of Medicine Western Michigan University Kalamazoo Michigan USA
| | - Keith Kenter
- Department of Orthopaedic Surgery, Homer Stryker MD School of Medicine Western Michigan University Kalamazoo Michigan USA
| | - Yong Li
- Department of Orthopaedic Surgery, Homer Stryker MD School of Medicine Western Michigan University Kalamazoo Michigan USA
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The Role of Satellite Cells in Skeletal Muscle Regeneration-The Effect of Exercise and Age. BIOLOGY 2021; 10:biology10101056. [PMID: 34681155 PMCID: PMC8533525 DOI: 10.3390/biology10101056] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Revised: 10/05/2021] [Accepted: 10/12/2021] [Indexed: 12/03/2022]
Abstract
Simple Summary Studies describing the effects of various forms of exercise and age on muscle regeneration were reviewed. Satellite cells are a heterogeneous group of cells that includes stem cells and skeletal muscle progenitor cells. Each skeletal muscle fiber has its own pool of satellite cells that remain inactive until the muscle is damaged. Minor damage within the cell membrane of muscle fibers is patched by fusing intracellular vesicles with the damaged sarcolemma. More severe muscle damage initiates a multistep regeneration process in which satellite cells play an essential role. The condition that initiates the cascade of reactions is the formation of inflammation at the structural discontinuity site, resulting in satellite cell activation. The multitude of reactions and pathways occurring during this process means that many different substances are involved in it and control it. Not all of them are well-understood yet. In parallel, the body’s own population of satellite cells is being rebuilt so that more fibers can be regenerated in the future. Athletes and the elderly are primarily at risk for muscle damage, and pathologies in muscle fiber regeneration cause serious diseases. Abstract The population of satellite cells (mSCs) is highly diversified. The cells comprising it differ in their ability to regenerate their own population and differentiate, as well as in the properties they exhibit. The heterogeneity of this group of cells is evidenced by multiple differentiating markers that enable their recognition, classification, labeling, and characterization. One of the main tasks of satellite cells is skeletal muscle regeneration. Myofibers are often damaged during vigorous exercise in people who participate in sports activities. The number of satellite cells and the speed of the regeneration processes that depend on them affect the time structure of an athlete’s training. This process depends on inflammatory cells. The multitude of reactions and pathways that occur during the regeneration process results in the participation and control of many factors that are activated and secreted during muscle fiber damage and at different stages of its regeneration. However, not all of them are well understood yet. This paper presents the current state of knowledge on satellite cell-dependent skeletal muscle regeneration. Studies describing the effects of various forms of exercise and age on this process were reviewed.
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Murach KA, Fry CS, Dupont-Versteegden EE, McCarthy JJ, Peterson CA. Fusion and beyond: Satellite cell contributions to loading-induced skeletal muscle adaptation. FASEB J 2021; 35:e21893. [PMID: 34480776 PMCID: PMC9293230 DOI: 10.1096/fj.202101096r] [Citation(s) in RCA: 46] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2021] [Revised: 08/13/2021] [Accepted: 08/17/2021] [Indexed: 12/14/2022]
Abstract
Satellite cells support adult skeletal muscle fiber adaptations to loading in numerous ways. The fusion of satellite cells, driven by cell-autonomous and/or extrinsic factors, contributes new myonuclei to muscle fibers, associates with load-induced hypertrophy, and may support focal membrane damage repair and long-term myonuclear transcriptional output. Recent studies have also revealed that satellite cells communicate within their niche to mediate muscle remodeling in response to resistance exercise, regulating the activity of numerous cell types through various mechanisms such as secretory signaling and cell-cell contact. Muscular adaptation to resistance and endurance activity can be initiated and sustained for a period of time in the absence of satellite cells, but satellite cell participation is ultimately required to achieve full adaptive potential, be it growth, function, or proprioceptive coordination. While significant progress has been made in understanding the roles of satellite cells in adult muscle over the last few decades, many conclusions have been extrapolated from regeneration studies. This review highlights our current understanding of satellite cell behavior and contributions to adaptation outside of regeneration in adult muscle, as well as the roles of satellite cells beyond fusion and myonuclear accretion, which are gaining broader recognition.
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Affiliation(s)
- Kevin A Murach
- The Center for Muscle Biology, University of Kentucky, Lexington, Kentucky, USA.,Molecular Muscle Mass Regulation Laboratory, Exercise Science Research Center, Department of Health, Human Performance, and Recreation, University of Arkansas, Fayetteville, Arkansas, USA.,Cell and Molecular Biology Program, University of Arkansas, Fayetteville, Arkansas, USA
| | - Christopher S Fry
- The Center for Muscle Biology, University of Kentucky, Lexington, Kentucky, USA.,Department of Athletic Training and Clinical Nutrition, College of Health Sciences, University of Kentucky, Lexington, Kentucky, USA
| | - Esther E Dupont-Versteegden
- The Center for Muscle Biology, University of Kentucky, Lexington, Kentucky, USA.,Department of Physical Therapy, College of Health Sciences, University of Kentucky, Lexington, Kentucky, USA
| | - John J McCarthy
- The Center for Muscle Biology, University of Kentucky, Lexington, Kentucky, USA.,Department of Physiology, College of Medicine, University of Kentucky, Lexington, Kentucky, USA
| | - Charlotte A Peterson
- The Center for Muscle Biology, University of Kentucky, Lexington, Kentucky, USA.,Department of Physical Therapy, College of Health Sciences, University of Kentucky, Lexington, Kentucky, USA.,Department of Physiology, College of Medicine, University of Kentucky, Lexington, Kentucky, USA
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12
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Westman AM, Peirce SM, Christ GJ, Blemker SS. Agent-based model provides insight into the mechanisms behind failed regeneration following volumetric muscle loss injury. PLoS Comput Biol 2021; 17:e1008937. [PMID: 33970905 PMCID: PMC8110270 DOI: 10.1371/journal.pcbi.1008937] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Accepted: 04/01/2021] [Indexed: 12/22/2022] Open
Abstract
Skeletal muscle possesses a remarkable capacity for repair and regeneration following a variety of injuries. When successful, this highly orchestrated regenerative process requires the contribution of several muscle resident cell populations including satellite stem cells (SSCs), fibroblasts, macrophages and vascular cells. However, volumetric muscle loss injuries (VML) involve simultaneous destruction of multiple tissue components (e.g., as a result of battlefield injuries or vehicular accidents) and are so extensive that they exceed the intrinsic capability for scarless wound healing and result in permanent cosmetic and functional deficits. In this scenario, the regenerative process fails and is dominated by an unproductive inflammatory response and accompanying fibrosis. The failure of current regenerative therapeutics to completely restore functional muscle tissue is not surprising considering the incomplete understanding of the cellular mechanisms that drive the regeneration response in the setting of VML injury. To begin to address this profound knowledge gap, we developed an agent-based model to predict the tissue remodeling response following surgical creation of a VML injury. Once the model was able to recapitulate key aspects of the tissue remodeling response in the absence of repair, we validated the model by simulating the tissue remodeling response to VML injury following implantation of either a decellularized extracellular matrix scaffold or a minced muscle graft. The model suggested that the SSC microenvironment and absence of pro-differentiation SSC signals were the most important aspects of failed muscle regeneration in VML injuries. The major implication of this work is that agent-based models may provide a much-needed predictive tool to optimize the design of new therapies, and thereby, accelerate the clinical translation of regenerative therapeutics for VML injuries.
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Affiliation(s)
- Amanda M. Westman
- Biomedical Engineering, University of Virginia, Charlottesville, Virginia, United States of America
| | - Shayn M. Peirce
- Biomedical Engineering, University of Virginia, Charlottesville, Virginia, United States of America
- Ophthalmology, University of Virginia, Charlottesville, Virginia, United States of America
| | - George J. Christ
- Biomedical Engineering, University of Virginia, Charlottesville, Virginia, United States of America
- Orthopaedic Surgery, University of Virginia, Charlottesville, Virginia, United States of America
- * E-mail: (GJC); (SSB)
| | - Silvia S. Blemker
- Biomedical Engineering, University of Virginia, Charlottesville, Virginia, United States of America
- Ophthalmology, University of Virginia, Charlottesville, Virginia, United States of America
- Orthopaedic Surgery, University of Virginia, Charlottesville, Virginia, United States of America
- Mechanical and Aerospace Engineering, University of Virginia, Charlottesville, Virginia, United States of America
- * E-mail: (GJC); (SSB)
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13
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Rugowska A, Starosta A, Konieczny P. Epigenetic modifications in muscle regeneration and progression of Duchenne muscular dystrophy. Clin Epigenetics 2021; 13:13. [PMID: 33468200 PMCID: PMC7814631 DOI: 10.1186/s13148-021-01001-z] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Accepted: 12/14/2020] [Indexed: 02/08/2023] Open
Abstract
Duchenne muscular dystrophy (DMD) is a multisystemic disorder that affects 1:5000 boys. The severity of the phenotype varies dependent on the mutation site in the DMD gene and the resultant dystrophin expression profile. In skeletal muscle, dystrophin loss is associated with the disintegration of myofibers and their ineffective regeneration due to defective expansion and differentiation of the muscle stem cell pool. Some of these phenotypic alterations stem from the dystrophin absence-mediated serine-threonine protein kinase 2 (MARK2) misplacement/downregulation in activated muscle stem (satellite) cells and neuronal nitric oxide synthase loss in cells committed to myogenesis. Here, we trace changes in DNA methylation, histone modifications, and expression of regulatory noncoding RNAs during muscle regeneration, from the stage of satellite cells to myofibers. Furthermore, we describe the abrogation of these epigenetic regulatory processes due to changes in signal transduction in DMD and point to therapeutic treatments increasing the regenerative potential of diseased muscles based on this acquired knowledge.
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Affiliation(s)
- Anna Rugowska
- Institute of Human Biology and Evolution, Faculty of Biology, Adam Mickiewicz University, ul. Uniwersytetu Poznańskiego 6, 61-614, Poznan, Poland
| | - Alicja Starosta
- Institute of Human Biology and Evolution, Faculty of Biology, Adam Mickiewicz University, ul. Uniwersytetu Poznańskiego 6, 61-614, Poznan, Poland
| | - Patryk Konieczny
- Institute of Human Biology and Evolution, Faculty of Biology, Adam Mickiewicz University, ul. Uniwersytetu Poznańskiego 6, 61-614, Poznan, Poland.
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14
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Papanikolaou K, Veskoukis AS, Draganidis D, Baloyiannis I, Deli CK, Poulios A, Jamurtas AZ, Fatouros IG. Redox-dependent regulation of satellite cells following aseptic muscle trauma: Implications for sports performance and nutrition. Free Radic Biol Med 2020; 161:125-138. [PMID: 33039652 DOI: 10.1016/j.freeradbiomed.2020.10.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Revised: 09/26/2020] [Accepted: 10/01/2020] [Indexed: 12/21/2022]
Abstract
Skeletal muscle satellite cells (SCs) are indispensable for tissue regeneration, remodeling and growth. Following myotrauma, SCs are activated, and assist in tissue repair. Exercise-induced muscle damage (EIMD) is characterized by a pronounced inflammatory response and the production of reactive oxygen species (ROS). Experimental evidence suggests that SCs kinetics (the propagation from a quiescent to an activated/proliferative state) following EIMD is redox-dependent and interconnected with changes in the SCs microenvironment (niche). Animal studies have shown that following aseptic myotrauma, antioxidant and/or anti-inflammatory supplementation leads to an improved recovery and skeletal muscle regeneration through enhanced SCs kinetics, suggesting a redox-dependent molecular mechanism. Although evidence suggests that antioxidant/anti-inflammatory compounds may prevent performance deterioration and enhance recovery, there is lack of information regarding the redox-dependent regulation of SCs responses following EIMD in humans. In this review, SCs kinetics following aseptic myotrauma, as well as the intrinsic redox-sensitive molecular mechanisms responsible for SCs responses are discussed. The role of redox status on SCs function should be further investigated in the future with human clinical trials in an attempt to elucidate the molecular pathways responsible for muscle recovery and provide information for potential nutritional strategies aiming at performance recovery.
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Affiliation(s)
- Konstantinos Papanikolaou
- Department of Physical Education and Sport Science, University of Thessaly, Karies, Trikala, 42132, Greece
| | - Aristidis S Veskoukis
- Department of Nutrition and Dietetics, University of Thessaly, Argonafton 1, 42132, Trikala, Greece; Department of Biochemistry and Biotechnology, University of Thessaly, Viopolis, Mezourlo, 41500, Larissa, Greece
| | - Dimitrios Draganidis
- Department of Physical Education and Sport Science, University of Thessaly, Karies, Trikala, 42132, Greece
| | - Ioannis Baloyiannis
- Department of Surgery, University Hospital of Larissa, Mezourlo, 41110, Larissa, Greece
| | - Chariklia K Deli
- Department of Physical Education and Sport Science, University of Thessaly, Karies, Trikala, 42132, Greece
| | - Athanasios Poulios
- Department of Physical Education and Sport Science, University of Thessaly, Karies, Trikala, 42132, Greece
| | - Athanasios Z Jamurtas
- Department of Physical Education and Sport Science, University of Thessaly, Karies, Trikala, 42132, Greece
| | - Ioannis G Fatouros
- Department of Physical Education and Sport Science, University of Thessaly, Karies, Trikala, 42132, Greece.
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15
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MICAL2 is essential for myogenic lineage commitment. Cell Death Dis 2020; 11:654. [PMID: 32811811 PMCID: PMC7434877 DOI: 10.1038/s41419-020-02886-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 07/29/2020] [Accepted: 07/29/2020] [Indexed: 01/25/2023]
Abstract
Contractile myofiber units are mainly composed of thick myosin and thin actin (F-actin) filaments. F-Actin interacts with Microtubule Associated Monooxygenase, Calponin And LIM Domain Containing 2 (MICAL2). Indeed, MICAL2 modifies actin subunits and promotes actin filament turnover by severing them and preventing repolymerization. In this study, we found that MICAL2 increases during myogenic differentiation of adult and pluripotent stem cells (PSCs) towards skeletal, smooth and cardiac muscle cells and localizes in the nucleus of acute and chronic regenerating muscle fibers. In vivo delivery of Cas9–Mical2 guide RNA complexes results in muscle actin defects and demonstrates that MICAL2 is essential for skeletal muscle homeostasis and functionality. Conversely, MICAL2 upregulation shows a positive impact on skeletal and cardiac muscle commitments. Taken together these data demonstrate that modulations of MICAL2 have an impact on muscle filament dynamics and its fine-tuned balance is essential for the regeneration of muscle tissues.
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16
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Unloading during skeletal muscle regeneration retards iNOS-expressing macrophage recruitment and perturbs satellite cell accumulation. Histochem Cell Biol 2020; 154:355-367. [DOI: 10.1007/s00418-020-01897-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/27/2020] [Indexed: 02/06/2023]
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17
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Tonniges JR, Velleman SG. Nutrient restriction and migration of turkey satellite cells. Poult Sci 2019; 98:7090-7096. [PMID: 31222280 PMCID: PMC8913961 DOI: 10.3382/ps/pez349] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Accepted: 06/11/2019] [Indexed: 11/20/2022] Open
Abstract
Post hatch muscle growth and the repair or regeneration of muscle after myofiber injury is mediated by satellite cells. Satellite cells proliferate, migrate, differentiate, and fuse with growing or regenerating myofibers. The proliferation and differentiation of satellite cells are affected by nutrition, but it is unknown how nutrition impacts satellite cell migration. The objective of the study was to determine the effect of a nutrient restriction on satellite cell migration. Satellite cells from the pectoralis major muscle of 1 and 49-day-old Randombred Control Line 2 turkeys were grown in culture, and migration was measured using a wound healing assay. Nutrient restrictions of 0, 5, 10, and 20% of the standard culture medium were applied starting immediately after scratch or 24 h prior to scratch. Nutrient restrictions of 5 and 20% increased 1 D satellite cell migration at 6 h post scratch compared to 1 D satellite cells with standard culture medium but had no effect after 12 h post scratch. Nutrient restrictions started 24 h prior to scratch increased 1 D satellite cell migration at 6 and 12 h post scratch compared to nutrient restrictions started immediately after scratch. The migration of 49 D satellite cells was not affected by the percentage or timing of the nutrient restriction. These data suggest that nutrition has only a minor effect on the migration of turkey pectoralis major muscle satellite cells. Therefore, the influence of nutrition on satellite cell migration is likely not an important factor for evaluating poultry diet formulations to optimize muscle growth and structure for improved meat protein and fat content as well as meat texture.
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Affiliation(s)
- Jeffrey R Tonniges
- The Ohio State University/Ohio Agricultural Research and Development Center, 1680 Madison Ave., Wooster, OH 44691
| | - Sandra G Velleman
- The Ohio State University/Ohio Agricultural Research and Development Center, 1680 Madison Ave., Wooster, OH 44691
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18
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Kargl CK, Nie Y, Evans S, Stout J, Shannahan JH, Kuang S, Gavin TP. Factors secreted from high glucose treated endothelial cells impair expansion and differentiation of human skeletal muscle satellite cells. J Physiol 2019; 597:5109-5124. [DOI: 10.1113/jp278165] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Accepted: 08/26/2019] [Indexed: 12/12/2022] Open
Affiliation(s)
| | - Yaohui Nie
- Department of Health and KinesiologyPurdue University
| | | | | | | | - Shihuan Kuang
- Department of Animal SciencesPurdue University West Lafayette IN USA
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19
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Liao CH, Lin LP, Yu TY, Hsu CC, Pang JHS, Tsai WC. Ibuprofen inhibited migration of skeletal muscle cells in association with downregulation of p130cas and CrkII expressions. Skelet Muscle 2019; 9:23. [PMID: 31464636 PMCID: PMC6714350 DOI: 10.1186/s13395-019-0208-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Accepted: 08/13/2019] [Indexed: 11/28/2022] Open
Abstract
Background Nonsteroidal anti-inflammatory drugs (NSAIDs) are commonly used to treat sports-related muscle injuries. However, NSAIDs were recently shown to impede the muscle healing process after acute injury. Migration of skeletal muscle cells is a crucial step during the muscle healing process. The present study was performed to investigate the effect and molecular mechanisms of action of ibuprofen, a commonly used NSAID, on the migration of skeletal muscle cells. Methods Skeletal muscle cells isolated from the gastrocnemius muscle of Sprague-Dawley rats were treated with ibuprofen. MTT assay (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) was used to evaluate cell viability, and cell apoptosis was evaluated by TUNEL assay, after ibuprofen treatment. Skeletal muscle cell migration and spreading were evaluated using the transwell filter migration assay and F-actin staining, respectively. The protein expression of p130cas and CrkII, which are cell migration facilitating genes, was determined by western blot analysis. The overexpression of p130cas of muscle cells was achieved by p130cas vector transfection. Results The results demonstrated that ibuprofen did not have a significant negative effect on cell viability and apoptosis. Ibuprofen inhibited the migration and spreading of skeletal muscle cells in a dose-dependent manner. Ibuprofen also dose-dependently decreased the protein expression of p130cas and CrkII. Furthermore, overexpression of p130cas resulted in the promotion of cell migration and spreading and counteracted ibuprofen-mediated inhibition. Conclusion This study suggested that ibuprofen exerts a potentially adverse effect on the migration of skeletal muscle cells by downregulating protein expression of p130cas and CrkII. These results indicate a possible mechanism underlying the possible negative effect of NSAIDs on muscle regeneration.
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Affiliation(s)
- Chih-Hao Liao
- Department of Physical Medicine and Rehabilitation, Chang Gung Memorial Hospital, No.123, Dinghu Rd., Guishan Dist, Taoyuan City, 333, Taiwan
| | - Li-Ping Lin
- Department of Physical Medicine and Rehabilitation, Chang Gung Memorial Hospital, No.123, Dinghu Rd., Guishan Dist, Taoyuan City, 333, Taiwan.,Graduate Institute of Clinical Medical Sciences, Chang Gung University, Taoyuan City, Taiwan
| | - Tung-Yang Yu
- Department of Physical Medicine and Rehabilitation, Chang Gung Memorial Hospital, No.123, Dinghu Rd., Guishan Dist, Taoyuan City, 333, Taiwan
| | - Chih-Chin Hsu
- College of Medicine, Chang Gung University, Taoyuan City, Taiwan.,Department of Physical Medicine and Rehabilitation, Chang Gung Memorial Hospital, Keelung, Taiwan
| | - Jong-Hwei S Pang
- Department of Physical Medicine and Rehabilitation, Chang Gung Memorial Hospital, No.123, Dinghu Rd., Guishan Dist, Taoyuan City, 333, Taiwan.,Graduate Institute of Clinical Medical Sciences, Chang Gung University, Taoyuan City, Taiwan
| | - Wen-Chung Tsai
- Department of Physical Medicine and Rehabilitation, Chang Gung Memorial Hospital, No.123, Dinghu Rd., Guishan Dist, Taoyuan City, 333, Taiwan. .,College of Medicine, Chang Gung University, Taoyuan City, Taiwan.
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20
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Insulin-Like Growth Factor Binding Protein-6 Promotes the Differentiation of Placental Mesenchymal Stem Cells into Skeletal Muscle Independent of Insulin-Like Growth Factor Receptor-1 and Insulin Receptor. Stem Cells Int 2019; 2019:9245938. [PMID: 30911300 PMCID: PMC6397983 DOI: 10.1155/2019/9245938] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Revised: 12/16/2018] [Accepted: 01/06/2019] [Indexed: 12/15/2022] Open
Abstract
As mesenchymal stem cells (MSCs) are being investigated for regenerative therapies to be used in the clinic, delineating the roles of the IGF system in MSC growth and differentiation, in vitro, is vital in developing these cellular therapies to treat degenerative diseases. Muscle differentiation is a multistep process, starting with commitment to the muscle lineage and ending with the formation of multinucleated fibers. Insulin-like growth factor binding protein-6 (IGFBP-6), relative to other IGFBPs, has high affinity for IGF-2. However, the role of IGFBP-6 in muscle development has not been clearly defined. Our previous studies showed that in vitro extracellular IGFBP-6 increased myogenesis in early stages and could enhance the muscle differentiation process in the absence of IGF-2. In this study, we identified the signal transduction mechanisms of IGFBP-6 on muscle differentiation by placental mesenchymal stem cells (PMSCs). We showed that muscle differentiation required activation of both AKT and MAPK pathways. Interestingly, we demonstrated that IGFBP-6 could compensate for IGF-2 loss and help enhance the muscle differentiation process by triggering predominantly the MAPK pathway independent of activating either IGF-1R or the insulin receptor (IR). These findings indicate the complex interactions between IGFBP-6 and IGFs in PMSC differentiation into the skeletal muscle and that the IGF signaling axis, specifically involving IGFBP-6, is important in muscle differentiation. Moreover, although the major role of IGFBP-6 is IGF-2 inhibition, it is not necessarily the case that IGFBP-6 is the main modulator of IGF-2.
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21
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Patel A, Xue Y, Hartley R, Sant V, Eles JR, Cui XT, Stolz DB, Sant S. Hierarchically aligned fibrous hydrogel films through microfluidic self-assembly of graphene and polysaccharides. Biotechnol Bioeng 2018; 115:2654-2667. [PMID: 30011077 DOI: 10.1002/bit.26801] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Revised: 05/25/2018] [Accepted: 06/26/2018] [Indexed: 12/17/2022]
Abstract
Despite significant interest in developing extracellular matrix (ECM)-inspired biomaterials to recreate native cell-instructive microenvironments, the major challenge in the biomaterial field is to recapitulate the complex structural and biophysical features of native ECM. These biophysical features include multiscale hierarchy, electrical conductivity, optimum wettability, and mechanical properties. These features are critical to the design of cell-instructive biomaterials for bioengineering applications such as skeletal muscle tissue engineering. In this study, we used a custom-designed film fabrication assembly, which consists of a microfluidic chamber to allow electrostatic charge-based self-assembly of oppositely charged polymer solutions forming a hydrogel fiber and eventually, a nanocomposite fibrous hydrogel film. The film recapitulates unidirectional hierarchical fibrous structure along with the conductive properties to guide initial alignment and myotube formation from cultured myoblasts. We combined high conductivity, and charge carrier mobility of graphene with biocompatibility of polysaccharides to develop graphene-polysaccharide nanocomposite fibrous hydrogel films. The incorporation of graphene in fibrous hydrogel films enhanced their wettability, electrical conductivity, tensile strength, and toughness without significantly altering their elastic properties (Young's modulus). In a proof-of-concept study, the mouse myoblast cells (C2C12) seeded on these nanocomposite fibrous hydrogel films showed improved spreading and enhanced myogenesis as evident by the formation of multinucleated myotubes, an early indicator of myogenesis. Overall, graphene-polysaccharide nanocomposite fibrous hydrogel films provide a potential biomaterial to promote skeletal muscle tissue regeneration.
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Affiliation(s)
- Akhil Patel
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Yingfei Xue
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Rebecca Hartley
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Vinayak Sant
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - James R Eles
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, Pennsylvania.,McGowan Institute for Regenerative Medicine, Pittsburgh, Pennsylvania
| | - Xinyan Tracy Cui
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, Pennsylvania.,McGowan Institute for Regenerative Medicine, Pittsburgh, Pennsylvania.,Center for the Neural Basis of Cognition, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Donna Beer Stolz
- McGowan Institute for Regenerative Medicine, Pittsburgh, Pennsylvania.,Center for Biologic Imaging, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania.,Department of Cell Biology and Pathology, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Shilpa Sant
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Pittsburgh, Pittsburgh, Pennsylvania.,Department of Bioengineering, University of Pittsburgh, Pittsburgh, Pennsylvania.,McGowan Institute for Regenerative Medicine, Pittsburgh, Pennsylvania
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22
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Guadagnin E, Mázala D, Chen YW. STAT3 in Skeletal Muscle Function and Disorders. Int J Mol Sci 2018; 19:ijms19082265. [PMID: 30072615 PMCID: PMC6121875 DOI: 10.3390/ijms19082265] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Revised: 07/19/2018] [Accepted: 07/23/2018] [Indexed: 12/17/2022] Open
Abstract
Signal transducer and activator of transcription 3 (STAT3) signaling plays critical roles in regulating skeletal muscle mass, repair, and diseases. In this review, we discuss the upstream activators of STAT3 in skeletal muscles, with a focus on interleukin 6 (IL6) and transforming growth factor beta 1 (TGF-β1). We will also discuss the double-edged effect of STAT3 activation in the muscles, including the role of STAT3 signaling in muscle hypertrophy induced by exercise training or muscle wasting in cachectic diseases and muscular dystrophies. STAT3 is a critical regulator of satellite cell self-renewal after muscle injury. STAT3 knock out affects satellite cell myogenic progression by impairing proliferation and inducing premature differentiation. Recent studies in STAT3 signaling demonstrated its direct role in controlling myogenic capacity of myoblasts and satellite cells, as well as the potential benefit in using STAT3 inhibitors to treat muscle diseases. However, prolonged STAT3 activation in muscles has been shown to be responsible for muscle wasting by activating protein degradation pathways. It is important to balance the extent of STAT3 activation and the duration and location (cell types) of the STAT3 signaling when developing therapeutic interventions. STAT3 signaling in other tissues and organs that can directly or indirectly affects skeletal muscle health are also discussed.
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Affiliation(s)
- Eleonora Guadagnin
- Department of Orthopeadic Surgery, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA.
| | - Davi Mázala
- Center for Genetic Medicine Research, Children's National Health System, Washington, DC 20010, USA.
| | - Yi-Wen Chen
- Center for Genetic Medicine Research, Children's National Health System, Washington, DC 20010, USA.
- Department Genomics and Precision Medicine, George Washington University, Washington, DC 20052, USA.
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23
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Thomas JD, Oliveira R, Sznajder ŁJ, Swanson MS. Myotonic Dystrophy and Developmental Regulation of RNA Processing. Compr Physiol 2018; 8:509-553. [PMID: 29687899 PMCID: PMC11323716 DOI: 10.1002/cphy.c170002] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Myotonic dystrophy (DM) is a multisystemic disorder caused by microsatellite expansion mutations in two unrelated genes leading to similar, yet distinct, diseases. DM disease presentation is highly variable and distinguished by differences in age-of-onset and symptom severity. In the most severe form, DM presents with congenital onset and profound developmental defects. At the molecular level, DM pathogenesis is characterized by a toxic RNA gain-of-function mechanism that involves the transcription of noncoding microsatellite expansions. These mutant RNAs disrupt key cellular pathways, including RNA processing, localization, and translation. In DM, these toxic RNA effects are predominantly mediated through the modulation of the muscleblind-like and CUGBP and ETR-3-like factor families of RNA binding proteins (RBPs). Dysfunction of these RBPs results in widespread RNA processing defects culminating in the expression of developmentally inappropriate protein isoforms in adult tissues. The tissue that is the focus of this review, skeletal muscle, is particularly sensitive to mutant RNA-responsive perturbations, as patients display a variety of developmental, structural, and functional defects in muscle. Here, we provide a comprehensive overview of DM1 and DM2 clinical presentation and pathology as well as the underlying cellular and molecular defects associated with DM disease onset and progression. Additionally, fundamental aspects of skeletal muscle development altered in DM are highlighted together with ongoing and potential therapeutic avenues to treat this muscular dystrophy. © 2018 American Physiological Society. Compr Physiol 8:509-553, 2018.
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Affiliation(s)
- James D. Thomas
- Department of Molecular Genetics and Microbiology, Center for NeuroGenetics and the Genetics Institute, University of Florida, College of Medicine, Gainesville, Florida, USA
| | - Ruan Oliveira
- Department of Molecular Genetics and Microbiology, Center for NeuroGenetics and the Genetics Institute, University of Florida, College of Medicine, Gainesville, Florida, USA
| | - Łukasz J. Sznajder
- Department of Molecular Genetics and Microbiology, Center for NeuroGenetics and the Genetics Institute, University of Florida, College of Medicine, Gainesville, Florida, USA
| | - Maurice S. Swanson
- Department of Molecular Genetics and Microbiology, Center for NeuroGenetics and the Genetics Institute, University of Florida, College of Medicine, Gainesville, Florida, USA
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24
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Praud C, Vauchez K, Zongo P, Vilquin JT. Modelling human myoblasts survival upon xenotransplantation into immunodeficient mouse muscle. Exp Cell Res 2018; 364:217-223. [PMID: 29458172 DOI: 10.1016/j.yexcr.2018.02.011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Revised: 02/13/2018] [Accepted: 02/14/2018] [Indexed: 12/07/2022]
Abstract
Cell transplantation has been challenged in several clinical indications of genetic or acquired muscular diseases, but therapeutic success were mitigated. To understand and improve the yields of tissue regeneration, we aimed at modelling the fate of CD56-positive human myoblasts after transplantation. Using immunodeficient severe combined immunodeficiency (SCID) mice as recipients, we assessed the survival, integration and satellite cell niche occupancy of human myoblasts by a triple immunohistochemical labelling of laminin, dystrophin and human lamin A/C. The counts were integrated into a classical mathematical decline equation. After injection, human cells were essentially located in the endomysium, then they disappeared progressively from D0 to D28. The final number of integrated human nuclei was grossly determined at D2 after injection, suggesting that no more efficient fusion between donor myoblasts and host fibers occurs after the resolution of the local damages created by needle insertion. Almost 1% of implanted human cells occupied a satellite-like cell niche. Our mathematical model validated by histological counting provided a reliable quantitative estimate of human myoblast survival and/or incorporation into SCID muscle fibers. Informations brought by histological labelling and this mathematical model are complementary.
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Affiliation(s)
| | - Karine Vauchez
- Sorbonne Université, INSERM, CNRS, Center for Research in Myology, Institute of Myology, F-75013, Paris, France
| | - Pascal Zongo
- BOA, INRA, Université de Tours, F-37380 Nouzilly, France
| | - Jean-Thomas Vilquin
- Sorbonne Université, INSERM, CNRS, Center for Research in Myology, Institute of Myology, F-75013, Paris, France
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25
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Kimmel JC, Chang AY, Brack AS, Marshall WF. Inferring cell state by quantitative motility analysis reveals a dynamic state system and broken detailed balance. PLoS Comput Biol 2018; 14:e1005927. [PMID: 29338005 PMCID: PMC5786322 DOI: 10.1371/journal.pcbi.1005927] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Revised: 01/26/2018] [Accepted: 12/13/2017] [Indexed: 02/02/2023] Open
Abstract
Cell populations display heterogeneous and dynamic phenotypic states at multiple scales. Similar to molecular features commonly used to explore cell heterogeneity, cell behavior is a rich phenotypic space that may allow for identification of relevant cell states. Inference of cell state from cell behavior across a time course may enable the investigation of dynamics of transitions between heterogeneous cell states, a task difficult to perform with destructive molecular observations. Cell motility is one such easily observed cell behavior with known biomedical relevance. To investigate heterogenous cell states and their dynamics through the lens of cell behavior, we developed Heteromotility, a software tool to extract quantitative motility features from timelapse cell images. In mouse embryonic fibroblasts (MEFs), myoblasts, and muscle stem cells (MuSCs), Heteromotility analysis identifies multiple motility phenotypes within the population. In all three systems, the motility state identity of individual cells is dynamic. Quantification of state transitions reveals that MuSCs undergoing activation transition through progressive motility states toward the myoblast phenotype. Transition rates during MuSC activation suggest non-linear kinetics. By probability flux analysis, we find that this MuSC motility state system breaks detailed balance, while the MEF and myoblast systems do not. Balanced behavior state transitions can be captured by equilibrium formalisms, while unbalanced switching between states violates equilibrium conditions and would require an external driving force. Our data indicate that the system regulating cell behavior can be decomposed into a set of attractor states which depend on the identity of the cell, together with a set of transitions between states. These results support a conceptual view of cell populations as dynamical systems, responding to inputs from signaling pathways and generating outputs in the form of state transitions and observable motile behaviors.
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Affiliation(s)
- Jacob C. Kimmel
- Dept. of Biochemistry and Biophysics, Center for Cellular Construction, University of California San Francisco, San Francisco, CA, United States of America
- Eli and Edythe Broad Center for Regenerative Medicine and Stem Cell Research, University of California San Francisco, San Francisco, CA, United States of America
| | - Amy Y. Chang
- Dept. of Biochemistry and Biophysics, Center for Cellular Construction, University of California San Francisco, San Francisco, CA, United States of America
| | - Andrew S. Brack
- Eli and Edythe Broad Center for Regenerative Medicine and Stem Cell Research, University of California San Francisco, San Francisco, CA, United States of America
- Dept. of Orthopedic Surgery, University of California San Francisco, San Francisco, CA, United States of America
| | - Wallace F. Marshall
- Dept. of Biochemistry and Biophysics, Center for Cellular Construction, University of California San Francisco, San Francisco, CA, United States of America
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26
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Kasemkijwattana C, Menetrey J, Somogyl G, Moreland MS, Fu FH, Buranapanitkit B, Watkins SC, Huard J. Development of Approaches to Improve the Healing following Muscle Contusion. Cell Transplant 2017; 7:585-98. [PMID: 9853587 DOI: 10.1177/096368979800700609] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Muscle injuries are a challenging problem in traumatology, and the most frequent occurrence in sports medicine. Muscle contusions are among the most common muscle injuries. Although this injury is capable of healing, an incomplete functional recovery often occurs, depending on the severity of the blunt trauma. We have developed an animal model of muscle contusion in mice (high energy blunt trauma) and characterized the muscle's ability to heal following this injury using histology and immunohistochemistry to determine the level of muscle regeneration and the development of scar tissue. We have observed a massive muscle regeneration occurring in the first 2 wk postinjury that is subsequently followed by the development of muscle fibrosis. Based on these observations, we propose that the enhancement of muscle growth and regeneration, as well as the prevention of fibrotic development, could be used as approach(es) to improve the healing of muscle injuries. In fact, we have identified three growth factors (bFGF, IGF-1, and NGF) capable of enhancing myoblast proliferation and differentiation in vitro and improving the healing of the injured muscle in vivo. Furthermore, the ability of adenovirus to mediate direct and ex vivo gene transfer of β-galactosidase into the injured site opens possibilities of delivering an efficient and persistent expression of these growth factors in the injured muscle. These studies should help in the development of strategies to promote efficient muscle healing with complete functional recovery following muscle contusion. © 1998 Elsevier Science Inc.
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Affiliation(s)
- C Kasemkijwattana
- Department of Orthopaedic Surgery, Musculoskeletal Research Center, University of Pittsburgh, and Children's Hospital of Pittsburgh, PA 15261, USA
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27
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Ratnayake D, Currie PD. Stem cell dynamics in muscle regeneration: Insights from live imaging in different animal models. Bioessays 2017; 39. [PMID: 28440546 DOI: 10.1002/bies.201700011] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
In recent years, live imaging has been adopted to study stem cells in their native environment at cellular resolution. In the skeletal muscle field, this has led to visualising the initial events of muscle repair in mouse, and the entire regenerative response in zebrafish. Here, we review recent discoveries in this field obtained from live imaging studies. Tracking of tissue resident stem cells, the satellite cells, following injury has captured the morphogenetic dynamics of stem/progenitor cells as they facilitate repair. Asymmetric satellite cell division generated a clonogenic progenitor pool, providing in vivo validation for this mechanism. Furthermore, there is an emerging role of stem/progenitor cell guidance at the injury site by cellular protrusions. This review concludes that live imaging is a critical tool for discovering the distinct processes that occur during regeneration, emphasising the importance of imaging in diverse animal models to capture the entire scope of stem cell functions. Also see the Video Abstract. Link to: https://youtube/tgUHSBD1N0g.
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Affiliation(s)
- Dhanushika Ratnayake
- Australian Regenerative Medicine Institute, Monash University, Clayton, VIC, Australia.,EMBL Australia, Monash University, Clayton, VIC, Australia
| | - Peter D Currie
- Australian Regenerative Medicine Institute, Monash University, Clayton, VIC, Australia.,EMBL Australia, Monash University, Clayton, VIC, Australia
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28
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Kawano F, Ono Y, Fujita R, Watanabe A, Masuzawa R, Shibata K, Hasegawa S, Nakata K, Nakai N. Prenatal myonuclei play a crucial role in skeletal muscle hypertrophy in rodents. Am J Physiol Cell Physiol 2016; 312:C233-C243. [PMID: 27927611 DOI: 10.1152/ajpcell.00151.2016] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Revised: 11/21/2016] [Accepted: 12/06/2016] [Indexed: 11/22/2022]
Abstract
Multinucleated muscle fibers are formed by the fusion of myogenic progenitor cells during embryonic and fetal myogenesis. However, the role of prenatally incorporated myonuclei in the skeletal muscle fibers of adult animals is poorly understood. We demonstrated, using muscle-specific reporter mice, that the prenatal myonuclei remained in the adult soleus muscle, although cardiotoxin injection caused the loss of prenatal myonuclei. Overloading by the tendon transection of synergists failed to induce compensatory hypertrophy in regenerated soleus muscle fibers of adult rats, whereas unloading by tail suspension normally induced the fiber atrophy. Loss of hypertrophying function correlated with the lowered histone acetylation at the transcription start site of Igf1r gene, which was one of the genes that did not respond to the overloading. These parameters were improved by the transplantation of cells harvested from the juvenile soleus muscles of neonatal rats in association with enhanced histone acetylation of Igf1r gene. These results indicated that the presence of prenatal myonuclei was closely related to the status of histone acetylation, which could regulate the responsiveness of muscle fibers to physiological stimuli.
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Affiliation(s)
- Fuminori Kawano
- Graduate School of Health Sciences, Matsumoto University, Matsumoto, Japan;
| | - Yusuke Ono
- Graduate School of Biomedical Science, Nagasaki University, Nagasaki, Japan
| | - Ryo Fujita
- Graduate School of Biomedical Science, Nagasaki University, Nagasaki, Japan
| | - Atsuya Watanabe
- Graduate School of Health Sciences, Matsumoto University, Matsumoto, Japan
| | - Ryo Masuzawa
- Graduate School of Health Sciences, Matsumoto University, Matsumoto, Japan
| | - Kazuhiro Shibata
- Graduate School of Health Sciences, Matsumoto University, Matsumoto, Japan
| | | | - Ken Nakata
- Graduate School of Medicine, Osaka University, Suita, Japan; and
| | - Naoya Nakai
- School of Human Cultures, University of Shiga Prefecture, Hikone, Japan
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29
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miR-143 regulates proliferation and differentiation of bovine skeletal muscle satellite cells by targeting IGFBP5. In Vitro Cell Dev Biol Anim 2016; 53:265-271. [PMID: 27800570 DOI: 10.1007/s11626-016-0109-y] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Accepted: 10/12/2016] [Indexed: 12/21/2022]
Abstract
Development of skeletal muscle is a complicated biological process regulated by various regulation factors and signal pathways. MicroRNAs (miRNAs) are novel gene regulators that control muscle cell development. microRNA-143 (miR-143) is highly expressed in skeletal muscle, and we found that miR-143 level is significantly increased during bovine skeletal muscle satellite cells (MSCs) differentiation process through microarray analysis and qRT-PCR detection. However, the function of miR-143 in bovine muscle development remained unclear. In our work, the functions of miR-143 in bovine MSCs myogenic differentiation were investigated. We discovered that IGFBP5 is directly regulated by miR-143 using a dual-luciferase reporter assay. Overexpression of miR-143 led to decreased level of IGFBP5 protein and restrained cell proliferation and differentiation, while downregulation of miR-143 resulted in increased levels of IGFBP5 protein and restrained cell proliferation but improved differentiation. IGFBP5, an important component of IGF signaling pathway, contributes greatly to bovine muscle cell development. A mechanism that miR-143 can regulate the proliferation and differentiation of bovine MSCs through changing expression of IGFBP5 was elucidated by our study.
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Abstract
The in vivo behaviors of skeletal muscle stem cells, i.e., satellite cells, during homeostasis and after injury are poorly understood. In this issue of Cell Stem Cell, Webster et al. (2016) now perform a tour de force intravital microscopic analysis of this population, showing that "ghost fiber" remnants act as scaffolds to guide satellite cell divisions after injury.
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Affiliation(s)
- Philippos Mourikis
- Inserm, IMRB U955-E10, 94000, Créteil, France; Université Paris Est Créteil, Faculté de Médecine, 94000, Créteil, & Ecole Nationale Vétérinaire d'Alfort, 94700, Maisons-Alfort, France
| | - Frédéric Relaix
- Inserm, IMRB U955-E10, 94000, Créteil, France; Université Paris Est Créteil, Faculté de Médecine, 94000, Créteil, & Ecole Nationale Vétérinaire d'Alfort, 94700, Maisons-Alfort, France; Etablissement Français du Sang, 94017, Créteil, France; APHP, Hôpital Henri Mondor, DHU Pepsy & Centre de Référence des Maladies Neuromusculaires GNMH, 94000, Créteil, France.
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31
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Keller AVP, Wainwright G, Shum-Siu A, Prince D, Hoeper A, Martin E, Magnuson DSK. Disruption of Locomotion in Response to Hindlimb Muscle Stretch at Acute and Chronic Time Points after a Spinal Cord Injury in Rats. J Neurotrauma 2016; 34:661-670. [PMID: 27196003 DOI: 10.1089/neu.2015.4227] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
After spinal cord injury (SCI) muscle contractures develop in the plegic limbs of many patients. Physical therapists commonly use stretching as an approach to avoid contractures and to maintain the extensibility of soft tissues. We found previously that a daily stretching protocol has a negative effect on locomotor recovery in rats with mild thoracic SCI. The purpose of the current study was to determine the effects of stretching on locomotor function at acute and chronic time points after moderately severe contusive SCI. Female Sprague-Dawley rats with 25 g-cm T10 contusion injuries received our standard 24-min stretching protocol starting 4 days (acutely) or 10 weeks (chronically) post-injury (5 days/week for 5 or 4 weeks, respectively). Locomotor function was assessed using the BBB (Basso, Beattie, and Bresnahan) Open Field Locomotor Scale, video-based kinematics, and gait analysis. Locomotor deficits were evident in the acute animals after only 5 days of stretching and increasing the perceived intensity of stretching at week 4 resulted in greater impairment. Stretching initiated chronically resulted in dramatic decrements in locomotor function because most animals had BBB scores of 0-3 for weeks 2, 3, and 4 of stretching. Locomotor function recovered to control levels for both groups within 2 weeks once daily stretching ceased. Histological analysis revealed no apparent signs of overt and persistent damage to muscles undergoing stretching. The current study extends our observations of the stretching phenomenon to a more clinically relevant moderately severe SCI animal model. The results are in agreement with our previous findings and further demonstrate that spinal cord locomotor circuitry is especially vulnerable to the negative effects of stretching at chronic time points. While the clinical relevance of this phenomenon remains unknown, we speculate that stretching may contribute to the lack of locomotor recovery in some patients.
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Affiliation(s)
- Anastasia V P Keller
- 1 Kentucky Spinal Cord Injury Research Center, University of Louisville , Louisville, Kentucky.,2 Department of Physiology and Biophysics, University of Louisville , Louisville, Kentucky
| | - Grace Wainwright
- 5 Department of J.B. Speed School of Engineering, University of Louisville , Louisville, Kentucky
| | - Alice Shum-Siu
- 1 Kentucky Spinal Cord Injury Research Center, University of Louisville , Louisville, Kentucky.,3 Department of Neurological Surgery, University of Louisville , Louisville, Kentucky
| | - Daniella Prince
- 1 Kentucky Spinal Cord Injury Research Center, University of Louisville , Louisville, Kentucky.,3 Department of Neurological Surgery, University of Louisville , Louisville, Kentucky
| | - Alyssa Hoeper
- 5 Department of J.B. Speed School of Engineering, University of Louisville , Louisville, Kentucky
| | - Emily Martin
- 5 Department of J.B. Speed School of Engineering, University of Louisville , Louisville, Kentucky
| | - David S K Magnuson
- 1 Kentucky Spinal Cord Injury Research Center, University of Louisville , Louisville, Kentucky.,3 Department of Neurological Surgery, University of Louisville , Louisville, Kentucky.,4 Department of Anatomical Sciences and Neurobiology, University of Louisville , Louisville, Kentucky
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32
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Umezawa T, Higa K, Serikawa M, Yamamoto M, Matsunaga S, Shimazaki J, Abe S. Proliferative activity of skeletal myoblast sheet by paracrine effects of mesenchymal stem cells. J Oral Biosci 2016; 58:158-166. [PMID: 32512684 DOI: 10.1016/j.job.2016.05.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Revised: 05/11/2016] [Accepted: 05/12/2016] [Indexed: 01/09/2023]
Abstract
OBJECTIVES The purpose of this study was to examine the proliferative activity enhancement of skeletal myoblasts in the presence and absence of mesenchymal stem cells (MSC). METHODS We artificially fabricated two types of cell sheets by co-culturing rabbit skeletal myoblast sheets with rabbit MSCs using type IA collagen gel (MC+), and cell sheets without rabbit MSCs (MC-). RESULTS The results of hematoxylin and eosin staining revealed that MC+ was thicker than MC- on day 7. Immunohistochemical staining revealed a low level of desmin expression in both sheets on day 2. Desmin expression increased at days 7 and 12, and desmin localization was consistent with the stratified area. Reverse transcription PCR revealed the presence of MyoD and PAX7 in both sheets on days 2, 7, and 12. The presence of myogenin was confirmed in both sheets on days 7 and 12. Hepatocyte growth factor expression was evident in MC+ on day 2, and in both sheets on day 7. Measurement of cell proliferative activity based on DNA cell cycle analysis indicated that MC+ had significantly higher cell proliferative activity than MC- on day 7. There were no significant differences in cell proliferative activity between MC+ and MC- on day 12. CONCLUSIONS This study demonstrated that the presence of MSCs could transiently enhance the proliferative activity of myoblasts, but that this enhancement is ultimately diminished due to contact inhibition.
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Affiliation(s)
- Takashi Umezawa
- Department of Anatomy, Tokyo Dental College, 2-9-18, Misaki-cho, Chiyoda-ku, Tokyo 101-0061, Japan.
| | - Kazunari Higa
- Department of Ophthalmology/Cornea Center, Tokyo Dental College, 5-11-13 Sugano Ichikawa-shi, Chiba 272-8513, Japan
| | - Masamitsu Serikawa
- Department of Anatomy, Tokyo Dental College, 2-9-18, Misaki-cho, Chiyoda-ku, Tokyo 101-0061, Japan
| | - Masahito Yamamoto
- Department of Anatomy, Tokyo Dental College, 2-9-18, Misaki-cho, Chiyoda-ku, Tokyo 101-0061, Japan
| | - Satoru Matsunaga
- Department of Anatomy, Tokyo Dental College, 2-9-18, Misaki-cho, Chiyoda-ku, Tokyo 101-0061, Japan
| | - Jun Shimazaki
- Department of Ophthalmology/Cornea Center, Tokyo Dental College, 5-11-13 Sugano Ichikawa-shi, Chiba 272-8513, Japan
| | - Shinichi Abe
- Department of Anatomy, Tokyo Dental College, 2-9-18, Misaki-cho, Chiyoda-ku, Tokyo 101-0061, Japan
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33
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Dumont NA, Bentzinger CF, Sincennes MC, Rudnicki MA. Satellite Cells and Skeletal Muscle Regeneration. Compr Physiol 2016; 5:1027-59. [PMID: 26140708 DOI: 10.1002/cphy.c140068] [Citation(s) in RCA: 425] [Impact Index Per Article: 53.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Skeletal muscles are essential for vital functions such as movement, postural support, breathing, and thermogenesis. Muscle tissue is largely composed of long, postmitotic multinucleated fibers. The life-long maintenance of muscle tissue is mediated by satellite cells, lying in close proximity to the muscle fibers. Muscle satellite cells are a heterogeneous population with a small subset of muscle stem cells, termed satellite stem cells. Under homeostatic conditions all satellite cells are poised for activation by stimuli such as physical trauma or growth signals. After activation, satellite stem cells undergo symmetric divisions to expand their number or asymmetric divisions to give rise to cohorts of committed satellite cells and thus progenitors. Myogenic progenitors proliferate, and eventually differentiate through fusion with each other or to damaged fibers to reconstitute fiber integrity and function. In the recent years, research has begun to unravel the intrinsic and extrinsic mechanisms controlling satellite cell behavior. Nonetheless, an understanding of the complex cellular and molecular interactions of satellite cells with their dynamic microenvironment remains a major challenge, especially in pathological conditions. The goal of this review is to comprehensively summarize the current knowledge on satellite cell characteristics, functions, and behavior in muscle regeneration and in pathological conditions.
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Affiliation(s)
- Nicolas A Dumont
- Sprott Centre for Stem Cell Research, Ottawa Hospital Research Institute, Ottawa, Ontario, Canada
| | - C Florian Bentzinger
- Sprott Centre for Stem Cell Research, Ottawa Hospital Research Institute, Ottawa, Ontario, Canada.,Nestlé Institute of Health Sciences, EPFL Campus, Lausanne, Switzerland
| | - Marie-Claude Sincennes
- Sprott Centre for Stem Cell Research, Ottawa Hospital Research Institute, Ottawa, Ontario, Canada
| | - Michael A Rudnicki
- Sprott Centre for Stem Cell Research, Ottawa Hospital Research Institute, Ottawa, Ontario, Canada.,Faculty of Medicine, Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario, Canada
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34
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Shelar SB, Narasimhan M, Shanmugam G, Litovsky SH, Gounder SS, Karan G, Arulvasu C, Kensler TW, Hoidal JR, Darley-Usmar VM, Rajasekaran NS. Disruption of nuclear factor (erythroid-derived-2)-like 2 antioxidant signaling: a mechanism for impaired activation of stem cells and delayed regeneration of skeletal muscle. FASEB J 2016; 30:1865-79. [PMID: 26839378 DOI: 10.1096/fj.201500153] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2015] [Accepted: 01/14/2016] [Indexed: 01/07/2023]
Abstract
Recently we have reported that age-dependent decline in antioxidant levels accelerated apoptosis and skeletal muscle degeneration. Here, we demonstrate genetic ablation of the master cytoprotective transcription factor, nuclear factor (erythroid-derived-2)-like 2 (Nrf2), aggravates cardiotoxin (CTX)-induced tibialis anterior (TA) muscle damage. Disruption of Nrf2 signaling sustained the CTX-induced burden of reactive oxygen species together with compromised expression of antioxidant genes and proteins. Transcript/protein expression of phenotypic markers of muscle differentiation, namely paired box 7 (satellite cell) and early myogenic differentiation and terminal differentiation (myogenin and myosin heavy chain 2) were increased on d 2 and 4 postinjury but later returned to baseline levels on d 8 and 15 in wild-type (WT) mice. In contrast, these responses were persistently augmented in Nrf2-null mice suggesting that regulation of the regeneration-related signaling mechanisms require Nrf2 for normal functioning. Furthermore, Nrf2-null mice displayed slower regeneration marked by dysregulation of embryonic myosin heavy chain temporal expression. Histologic observations illustrated that Nrf2-null mice displayed smaller, immature TA muscle fibers compared with WT counterparts on d 15 after CTX injury. Improvement in TA muscle morphology and gain in muscle mass evident in the WT mice was not noticeable in the Nrf2-null animals. Taken together these data show that the satellite cell activation, proliferation, and differentiation requires a functional Nrf2 system for effective healing following injury.-Shelar, S. B., Narasimhan, M., Shanmugam, G., Litovsky, S. H., Gounder, S. S., Karan, G., Arulvasu, C., Kensler, T. W., Hoidal, J. R., Darley-Usmar, V. M., Rajasekaran, N. S. Disruption of nuclear factor (erythroid-derived-2)-like 2 antioxidant signaling: a mechanism for impaired activation of stem cells and delayed regeneration of skeletal muscle.
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Affiliation(s)
- Sandeep Balu Shelar
- Cardiac Aging and Redox Signaling Laboratory, Division of Molecular and Cellular Pathology, Department of Pathology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Madhusudhanan Narasimhan
- Department of Pharmacology and Neuroscience, Texas Tech University Health Sciences Center, Lubbock, Texas, USA
| | - Gobinath Shanmugam
- Cardiac Aging and Redox Signaling Laboratory, Division of Molecular and Cellular Pathology, Department of Pathology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Silvio Hector Litovsky
- Division of Anatomic Pathology, Department of Pathology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Sellamuthu S Gounder
- Division of Cardiovascular Medicine/Pulmonary Medicine, Department of Medicine, University of Utah School of Medicine, Salt Lake City, Utah, USA
| | | | | | - Thomas W Kensler
- Department of Pharmacology & Chemical Biology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - John R Hoidal
- Division of Cardiovascular Medicine/Pulmonary Medicine, Department of Medicine, University of Utah School of Medicine, Salt Lake City, Utah, USA
| | - Victor M Darley-Usmar
- Center for Free Radical Biology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Namakkal S Rajasekaran
- Cardiac Aging and Redox Signaling Laboratory, Division of Molecular and Cellular Pathology, Department of Pathology, University of Alabama at Birmingham, Birmingham, Alabama, USA; Division of Cardiovascular Medicine/Pulmonary Medicine, Department of Medicine, University of Utah School of Medicine, Salt Lake City, Utah, USA; Center for Free Radical Biology, University of Alabama at Birmingham, Birmingham, Alabama, USA;
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35
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Expression of CCAAT/Enhancer Binding Protein Beta in Muscle Satellite Cells Inhibits Myogenesis in Cancer Cachexia. PLoS One 2015; 10:e0145583. [PMID: 26709824 PMCID: PMC4692409 DOI: 10.1371/journal.pone.0145583] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Accepted: 12/04/2015] [Indexed: 01/09/2023] Open
Abstract
Cancer cachexia is a paraneoplastic syndrome that causes profound weight loss and muscle mass atrophy and is estimated to be the cause of up to 30% of cancer deaths. Though the exact cause is unknown, patients with cancer cachexia have increased muscle protein catabolism. In healthy muscle, injury activates skeletal muscle stem cells, called satellite cells, to differentiate and promote regeneration. Here, we provide evidence that this mechanism is inhibited in cancer cachexia due to persistent expression of CCAAT/Enhancer Binding Protein beta (C/EBPβ) in muscle myoblasts. C/EBPβ is a bzip transcription factor that is expressed in muscle satellite cells and is normally downregulated upon differentiation. However, in myoblasts exposed to a cachectic milieu, C/EBPβ expression remains elevated, despite activation to differentiate, resulting in the inhibition of myogenin expression and myogenesis. In vivo, cancer cachexia results in increased number of Pax7+ cells that also express C/EBPβ and the inhibition of normal repair mechanisms. Loss of C/EBPβ expression in primary myoblasts rescues differentiation under cachectic conditions without restoring myotube size, indicating that C/EBPβ is an important inhibitor of myogenesis in cancer cachexia.
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36
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Chang W, Antoku S, Östlund C, Worman HJ, Gundersen GG. Linker of nucleoskeleton and cytoskeleton (LINC) complex-mediated actin-dependent nuclear positioning orients centrosomes in migrating myoblasts. Nucleus 2015; 6:77-88. [PMID: 25587885 DOI: 10.1080/19491034.2015.1004947] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
Abstract
Myoblast migration is essential for muscle development and repair; however, the factors that contribute to the polarity of migrating myoblasts are relatively unknown. We find that randomly migrating C2C12 myoblasts orient their centrosomes in the direction of migration. Using wounded monolayers, we further show that centrosome orientation is stimulated by the serum factor lysophosphatidic acid (LPA) and involves the rearward movement of the nucleus while the centrosome is maintained at the cell centroid. The rate of nuclear movement correlated with that of actin retrograde flow and both cytochalasin D and blebbistatin prevented nuclear movement and centrosome orientation. Actin-dependent rearward nuclear movement in fibroblasts is mediated by assembly of nuclear membrane nesprin-2G and SUN2 LINC complexes into transmembrane actin-associated nuclear (TAN) lines anchored by A-type lamins and emerin. In C2C12 myoblasts, depletion of nesprin-2G, SUN2 or lamin A/C prevented nuclear movement and endogenous nesprin-2G and a chimeric GFP-mini-nesprin-2G formed TAN lines during nuclear movement. Depleting nesprin-2G strongly interfered with directed cell migration and reduced the efficiency of myoblast fusion into multinucleated myotubes. Our results show that nuclear movement contributes to centrosome orientation and polarity for efficient migration and fusion of myoblasts. Given that mutations in the genes encoding A-type lamins, nesprin-2 and SUN2 cause Emery-Dreifuss muscular dystrophy and related myopathies, our results have implications for understanding the mechanism of disease pathogenesis.
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Affiliation(s)
- Wakam Chang
- a Department of Pathology and Cell Biology ; College of Physicians and Surgeons; Columbia University ; New York , NY USA
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Morsoleto MJMS, Morsoleto FMS, Alves de Matos AP, Morgado FMR, Anaruma CA. A Study of the Effects of Phonophoretic Application of Hydrocortisone on the Regeneration of Injuries to Skeletal Muscle. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2015; 21 Suppl 5:77-78. [PMID: 26227719 DOI: 10.1017/s1431927615014191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Affiliation(s)
| | | | | | - F M R Morgado
- 2Department of Biology,Universidade de Aveiro,Aveiro,Portugal
| | - C A Anaruma
- 5Department of Biosciences,State University of Sao Paulo (UNESP),Brazil
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Sládková J, Spáčilová J, Čapek M, Tesařová M, Hansíková H, Honzík T, Martínek J, Zámečník J, Kostková O, Zeman J. Analysis of Mitochondrial Network Morphology in Cultured Myoblasts from Patients with Mitochondrial Disorders. Ultrastruct Pathol 2015. [DOI: 10.3109/01913123.2015.1054013] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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Moresi V, Marroncelli N, Adamo S. New insights into the epigenetic control of satellite cells. World J Stem Cells 2015; 7:945-955. [PMID: 26240681 PMCID: PMC4515437 DOI: 10.4252/wjsc.v7.i6.945] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/26/2014] [Revised: 02/12/2015] [Accepted: 05/11/2015] [Indexed: 02/06/2023] Open
Abstract
Epigenetics finely tunes gene expression at a functional level without modifying the DNA sequence, thereby contributing to the complexity of genomic regulation. Satellite cells (SCs) are adult muscle stem cells that are important for skeletal post-natal muscle growth, homeostasis and repair. The understanding of the epigenome of SCs at different stages and of the multiple layers of the post-transcriptional regulation of gene expression is constantly expanding. Dynamic interactions between different epigenetic mechanisms regulate the appropriate timing of muscle-specific gene expression and influence the lineage fate of SCs. In this review, we report and discuss the recent literature about the epigenetic control of SCs during the myogenic process from activation to proliferation and from their commitment to a muscle cell fate to their differentiation and fusion to myotubes. We describe how the coordinated activities of the histone methyltransferase families Polycomb group (PcG), which represses the expression of developmentally regulated genes, and Trithorax group, which antagonizes the repressive activity of the PcG, regulate myogenesis by restricting gene expression in a time-dependent manner during each step of the process. We discuss how histone acetylation and deacetylation occurs in specific loci throughout SC differentiation to enable the time-dependent transcription of specific genes. Moreover, we describe the multiple roles of microRNA, an additional epigenetic mechanism, in regulating gene expression in SCs, by repressing or enhancing gene transcription or translation during each step of myogenesis. The importance of these epigenetic pathways in modulating SC activation and differentiation renders them as promising targets for disease interventions. Understanding the most recent findings regarding the epigenetic mechanisms that regulate SC behavior is useful from the perspective of pharmacological manipulation for improving muscle regeneration and for promoting muscle homeostasis under pathological conditions.
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Network Analysis for the Identification of Differentially Expressed Hub Genes Using Myogenin Knock-down Muscle Satellite Cells. PLoS One 2015. [PMID: 26200109 PMCID: PMC4511796 DOI: 10.1371/journal.pone.0133597] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Muscle, a multinucleate syncytium formed by the fusion of mononuclear myoblasts, arises from quiescent progenitors (satellite cells) via activation of muscle-specific transcription factors (MyoD, Myf5, myogenin: MYOG, and MRF4). Subsequent to a decline in Pax7, induction in the expression of MYOG is a hallmark of myoblasts that have entered the differentiation phase following cell cycle withdrawal. It is evident that MYOG function cannot be compensated by any other myogenic regulatory factors (MRFs). Despite a plethora of information available regarding MYOG, the mechanism by which MYOG regulates muscle cell differentiation has not yet been identified. Using an RNA-Seq approach, analysis of MYOG knock-down muscle satellite cells (MSCs) have shown that genes associated with cell cycle and division, DNA replication, and phosphate metabolism are differentially expressed. By constructing an interaction network of differentially expressed genes (DEGs) using GeneMANIA, cadherin-associated protein (CTNNA2) was identified as the main hub gene in the network with highest node degree. Four functional clusters (modules or communities) were identified in the network and the functional enrichment analysis revealed that genes included in these clusters significantly contribute to skeletal muscle development. To confirm this finding, in vitro studies revealed increased expression of CTNNA2 in MSCs on day 12 compared to day 10. Expression of CTNNA2 was decreased in MYOG knock-down cells. However, knocking down CTNNA2, which leads to increased expression of extracellular matrix (ECM) genes (type I collagen α1 and type I collagen α2) along with myostatin (MSTN), was not found significantly affecting the expression of MYOG in C2C12 cells. We therefore propose that MYOG exerts its regulatory effects by acting upstream of CTNNA2, which in turn regulates the differentiation of C2C12 cells via interaction with ECM genes. Taken together, these findings highlight a new mechanism by which MYOG interacts with CTNNA2 in order to promote myoblast differentiation.
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Ohira T, Wang XD, Ito T, Kawano F, Goto K, Izawa T, Ohno H, Kizaki T, Ohira Y. Macrophage deficiency in osteopetrotic (op/op) mice inhibits activation of satellite cells and prevents hypertrophy in single soleus fibers. Am J Physiol Cell Physiol 2015; 308:C848-55. [PMID: 25788575 DOI: 10.1152/ajpcell.00348.2014] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Accepted: 03/18/2015] [Indexed: 12/31/2022]
Abstract
Effects of macrophage on the responses of soleus fiber size to hind limb unloading and reloading were studied in osteopetrotic homozygous (op/op) mice with inactivated mutation of macrophage colony-stimulating factor (M-CSF) gene and in wild-type (+/+) and heterozygous (+/op) mice. The basal levels of mitotically active and quiescent satellite cell (-46 and -39% vs. +/+, and -40 and -30% vs. +/op) and myonuclear number (-29% vs. +/+ and -28% vs. +/op) in fibers of op/op mice were significantly less than controls. Fiber length and sarcomere number in op/op were also less than +/+ (-22%) and +/op (-21%) mice. Similar trend was noted in fiber cross-sectional area (CSA, -15% vs. +/+, P = 0.06, and -14% vs. +/op, P = 0.07). The sizes of myonuclear domain, cytoplasmic volume per myonucleus, were identical in all types of mice. The CSA, length, and the whole number of sarcomeres, myonuclei, and mitotically active and quiescent satellite cells, as well as myonuclear domain, in single muscle fibers were decreased after 10 days of unloading in all types of mice, although all of these parameters in +/+ and +/op mice were increased toward the control values after 10 days of reloading. However, none of these levels in op/op mice were recovered. Data suggest that M-CSF and/or macrophages are important to activate satellite cells, which cause increase of myonuclear number during fiber hypertrophy. However, it is unclear why their responses to general growth and reloading after unloading are different.
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Affiliation(s)
- T Ohira
- Space Biomedical Research Office, Japan Aerospace Exploration Agency, Tsukuba City, Ibaraki, Japan
| | - X D Wang
- Graduate School of Medicine, Osaka University, Toyonaka City, Osaka, Japan
| | - T Ito
- Laboratory Animal Center, Yamagata University School of Medicine, Yamagata City, Yamagata, Japan
| | - F Kawano
- Graduate School of Medicine, Osaka University, Toyonaka City, Osaka, Japan
| | - K Goto
- Graduate School of Health Sciences, Toyohashi SOZO University, Toyohashi City, Aichi, Japan
| | - T Izawa
- Graduate School of Health and Sports Science, Doshisha University, Kyotanabe City, Kyoto, Japan; Research Center for Adipocyte and Muscle Science, Doshisha University, Kyotanabe City, Kyoto, Japan; and
| | - H Ohno
- Department of Molecular Predictive Medicine and Sport Science, School of Medicine, Kyorin University, Mitaka City, Tokyo, Japan
| | - T Kizaki
- Department of Molecular Predictive Medicine and Sport Science, School of Medicine, Kyorin University, Mitaka City, Tokyo, Japan
| | - Y Ohira
- Graduate School of Health and Sports Science, Doshisha University, Kyotanabe City, Kyoto, Japan; Research Center for Adipocyte and Muscle Science, Doshisha University, Kyotanabe City, Kyoto, Japan; and
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42
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Ward CL, Ji L, Corona BT. An Autologous Muscle Tissue Expansion Approach for the Treatment of Volumetric Muscle Loss. Biores Open Access 2015; 4:198-208. [PMID: 26309796 PMCID: PMC4497650 DOI: 10.1089/biores.2015.0009] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Volumetric muscle loss (VML) is a hallmark of orthopedic trauma with no current standard of care. As a potential therapy for some VML indications, autologous minced muscle grafts (1 mm(3) pieces of muscle) are effective in promoting remarkable de novo fiber regeneration. But they require ample donor muscle tissue and therefore may be limited in their application for large clinical VML. Here, we tested the hypothesis that autologous minced grafts may be volume expanded in a collagen hydrogel, allowing for the use of lesser autologous muscle while maintaining regenerative and functional efficacy. The results of the study indicate that 50% (but not 75%) less minced graft tissue suspended in a collagen hydrogel promoted a functional improvement similar to that of a 100% minced graft repair. However, approximately half of the number of fibers regenerated de novo with 50% graft repair. Moreover, the fibers that regenerated had a smaller cross-sectional area. These findings support the concept of using autologous minced grafts for the regeneration of muscle tissue after VML, but indicate the need to identify optimal carrier materials for expansion.
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Affiliation(s)
- Catherine L. Ward
- US Army Institute of Surgical Research, Extremity Trauma and Regenerative Medicine, Fort Sam Houston, Texas
| | - Lisa Ji
- US Army Institute of Surgical Research, Extremity Trauma and Regenerative Medicine, Fort Sam Houston, Texas
| | - Benjamin T. Corona
- US Army Institute of Surgical Research, Extremity Trauma and Regenerative Medicine, Fort Sam Houston, Texas
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43
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Meyer GA, Farris AL, Sato E, Gibbons M, Lane JG, Ward SR, Engler AJ. Muscle progenitor cell regenerative capacity in the torn rotator cuff. J Orthop Res 2015; 33:421-9. [PMID: 25410765 PMCID: PMC4346515 DOI: 10.1002/jor.22786] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/19/2014] [Accepted: 11/06/2014] [Indexed: 02/04/2023]
Abstract
Chronic rotator cuff (RC) tears affect a large portion of the population and result in substantial upper extremity impairment, shoulder weakness, pain, and limited range of motion. Regardless of surgical or conservative treatment, persistent atrophic muscle changes limit functional restoration and may contribute to surgical failure. We hypothesized that deficits in the skeletal muscle progenitor (SMP) cell pool could contribute to poor muscle recovery following tendon repair. Biopsies were obtained from patients undergoing arthroscopic RC surgery. The SMP population was quantified, isolated, and assayed in culture for its ability to proliferate and fuse in vitro and in vivo. The SMP population was larger in muscles from cuffs with partial tears compared with no tears or full thickness tears. However, SMPs from muscles in the partial tear group also exhibited reduced proliferative ability. Cells from all cuff states were able to fuse robustly in culture and engraft when injected into injured mouse muscle, suggesting that when given the correct signals, SMPs are capable of contributing to muscle hypertrophy and regeneration regardless of tear severity. The fact that this does not appear to happen in vivo helps focus future therapeutic targets for promoting muscle recovery following rotator cuff repairs and may help improve clinical outcomes.
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Affiliation(s)
- Gretchen A. Meyer
- Investigation performed at the Department of Bioengineering, University of California, San Diego; La Jolla, CA 92093
| | - Ashley L. Farris
- Investigation performed at the Department of Bioengineering, University of California, San Diego; La Jolla, CA 92093
| | - Eugene Sato
- Investigation performed at the Department of Bioengineering, University of California, San Diego; La Jolla, CA 92093
| | - Michael Gibbons
- Investigation performed at the Department of Bioengineering, University of California, San Diego; La Jolla, CA 92093
| | - John G. Lane
- Investigation performed at the Department of Orthopaedic Surgery, University of California, San Diego; La Jolla, CA 92093
| | - Samuel R. Ward
- Investigation performed at the Department of Orthopaedic Surgery, University of California, San Diego; La Jolla, CA 92093,Investigation performed at the Department of Radiology, University of California, San Diego; La Jolla, CA 92093,Corresponding Authors: Dr. Adam J. Engler, 9500 Gilman Drive / MC 0695, La Jolla, CA 92093, Tel: 858-246-0678 Fax: 858-246-1469, , Dr. Samuel R. Ward, 9500 Gilman Drive / MC 0610, La Jolla, CA 92093, Tel: 858-534-4918 Fax: 858-822-3807,
| | - Adam J. Engler
- Investigation performed at the Department of Bioengineering, University of California, San Diego; La Jolla, CA 92093,Sanford Consortium for Regenerative Medicine; La Jolla, CA 92037,Corresponding Authors: Dr. Adam J. Engler, 9500 Gilman Drive / MC 0695, La Jolla, CA 92093, Tel: 858-246-0678 Fax: 858-246-1469, , Dr. Samuel R. Ward, 9500 Gilman Drive / MC 0610, La Jolla, CA 92093, Tel: 858-534-4918 Fax: 858-822-3807,
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44
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Zhu R, Wu G, Liu X, Shi D, Cao B, Gu R, Xiao J, Liao H. PNIPAM hydrogel induces skeletal muscle inflammation response. RSC Adv 2015. [DOI: 10.1039/c5ra01679g] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
In this work, we used the injectable PNIPAM hydrogel as a new bio-driver to induce chronic skeletal muscle inflammation response.
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Affiliation(s)
- Rong Zhu
- Department of Anatomy
- Key Laboratory of Construction and Detection of Guangdong Province
- Southern Medical University
- Guang Zhou
- China
| | - Gang Wu
- Emergency Department
- Nan Fang Hospital
- Southern Medical University
- Guang Zhou
- China
| | - Xinghui Liu
- Department of Anatomy
- Key Laboratory of Construction and Detection of Guangdong Province
- Southern Medical University
- Guang Zhou
- China
| | - DanDan Shi
- Department of Anatomy
- Key Laboratory of Construction and Detection of Guangdong Province
- Southern Medical University
- Guang Zhou
- China
| | - Biao Cao
- Department of Anatomy
- Key Laboratory of Construction and Detection of Guangdong Province
- Southern Medical University
- Guang Zhou
- China
| | - Ruicai Gu
- Department of Anatomy
- Key Laboratory of Construction and Detection of Guangdong Province
- Southern Medical University
- Guang Zhou
- China
| | - Jiangwei Xiao
- Department of Anatomy
- Key Laboratory of Construction and Detection of Guangdong Province
- Southern Medical University
- Guang Zhou
- China
| | - Hua Liao
- Department of Anatomy
- Key Laboratory of Construction and Detection of Guangdong Province
- Southern Medical University
- Guang Zhou
- China
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45
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Effects of type IV collagen on myogenic characteristics of IGF-I gene-engineered myoblasts. J Biosci Bioeng 2014; 119:596-603. [PMID: 25454061 DOI: 10.1016/j.jbiosc.2014.10.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2014] [Revised: 09/30/2014] [Accepted: 10/15/2014] [Indexed: 12/29/2022]
Abstract
Skeletal muscle regeneration requires migration, proliferation and fusion of myoblasts to form multinucleated myotubes. In our previous study, we showed that insulin-like growth factor (IGF)-I gene delivery stimulates the proliferation and differentiation of mouse myoblast C2C12 cells and promotes the contractile force generated by tissue-engineered skeletal muscles. The aim of this study was to investigate the effects of the extracellular matrix on IGF-I gene-engineered C2C12 cells in vitro. Retroviral vectors for doxycycline (Dox)-inducible expression of the IGF-I gene were transduced into C2C12 cells. When cultured on a type IV collagen-coated surface, we observed significant increases in the migration speed and number of IGF-I gene-engineered C2C12 cells with Dox addition, designated as C2C12/IGF (+) cells. Co-culture of C2C12/IGF (+) cells and parental C2C12 cells, which had been cultured in differentiation medium for 3 days, greatly enhanced myotube formation. Moreover, type IV collagen supplementation promoted the fusion of C2C12/IGF (+) cells with differentiated C2C12 cells and increased the number of myotubes with striations. Myotubes formed by C2C12/IGF (+) cells cultured on type IV collagen showed a dynamic contractile activity in response to electrical pulse stimulation. These findings indicate that type IV collagen promotes skeletal muscle regeneration mediated by IGF-I-expressing myoblasts, which may have important clinical implications in the design of myoblast-based therapies.
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46
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Transplantation of devitalized muscle scaffolds is insufficient for appreciable de novo muscle fiber regeneration after volumetric muscle loss injury. Cell Tissue Res 2014; 358:857-73. [PMID: 25300647 DOI: 10.1007/s00441-014-2006-6] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2014] [Accepted: 09/09/2014] [Indexed: 10/24/2022]
Abstract
Volumetric muscle loss (VML) is a traumatic and functionally debilitating muscle injury with limited treatment options. Developmental regenerative therapies for the repair of VML typically comprise an ECM scaffold. In this study, we tested if the complete reliance on host cell migration to a devitalized muscle scaffold without myogenic cells is sufficient for de novo muscle fiber regeneration. Devitalized (muscle ECM with no living cells) and, as a positive control, vital minced muscle grafts were transplanted to a VML defect in the tibialis anterior muscle of Lewis rats. Eight weeks post-injury, devitalized grafts did not appreciably promote de novo muscle fiber regeneration within the defect area, and instead remodeled into a fibrotic tissue mass. In contrast, transplantation of vital minced muscle grafts promoted de novo muscle fiber regeneration. Notably, pax7+ cells were absent in remote regions of the defect site repaired with devitalized scaffolds. At 2 weeks post-injury, the devitalized grafts were unable to promote an anti-inflammatory phenotype, while vital grafts appeared to progress to a pro-regenerative inflammatory response. The putative macrophage phenotypes observed in vivo were supported in vitro, in which soluble factors released from vital grafts promoted an M2-like macrophage polarization, whereas devitalized grafts failed to do so. These observations indicate that although the remaining muscle mass serves as a source of myogenic cells in close proximity to the defect site, a devitalized scaffold without myogenic cells is inadequate to appreciably promote de novo muscle fiber regeneration throughout the VML defect.
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Abstract
In recent years, our views on how DNA and genes are organised and regulated have evolved significantly. One example is provided by reports that single DNA strands in the double helix could carry distinct forms of information. That chromatids carrying old and nascently replicated DNA strands are recognised by the mitotic machinery, then segregated in a concerted way to distinct daughter cells after cell division is remarkable. Notably, this phenomenon in several cases has been associated with the cell fate choice of resulting daughter cells. Here, we review the evidence for asymmetric or template DNA strand segregation in mammals with a focus on skeletal muscle.
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Affiliation(s)
- Brendan Evano
- Institut Pasteur, Stem Cells & Development, Department of Developmental & Stem Cell Biology, CNRS URA 2578, 25 rue du Dr. Roux, Paris 75015, France
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Horie M, Enomoto M, Shimoda M, Okawa A, Miyakawa S, Yagishita K. Enhancement of satellite cell differentiation and functional recovery in injured skeletal muscle by hyperbaric oxygen treatment. J Appl Physiol (1985) 2014; 116:149-55. [DOI: 10.1152/japplphysiol.00235.2013] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Recently, the use of hyperbaric oxygen (HBO) treatments by elite athletes to accelerate recovery from muscle injuries has become increasingly popular. However, the mechanism of promoting muscle regeneration under HBO conditions has not yet been defined. In this study, we investigated whether HBO treatments promoted muscle regeneration and modulated muscle regulatory factor expression in a rat skeletal muscle injury model. Muscle injury was induced by injecting cardiotoxin (CTX) into the tibialis anterior (TA) muscles. As the HBO treatment, rats were placed in an animal chamber with 100% oxygen under 2.5 atmospheres absolute for 2 h/day, 5 days/wk for 2 wk. We then performed histological analyses, measured the maximum force-producing capacity of the regenerating muscle fibers, and performed quantitative RT-PCR analysis of muscle regulatory factor mRNAs. The cross-sectional areas and maximum force-producing capacity of the regenerating muscle fibers were increased by HBO treatment after injury. The mRNA expression of MyoD, myogenin, and IGF-1 increased significantly in the HBO group at 3 and 5 days after injury. The number of Pax7+/MyoD+, Pax7−/MyoD+, and Pax7+/BrdU+-positive nuclei was increased by HBO treatment. In this study, we demonstrated that HBO treatment accelerated satellite cell proliferation and myofiber maturation in rat muscle that was injured by a CTX injection. These results suggest that HBO treatment accelerates healing and functional recovery after muscle injury.
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Affiliation(s)
- Masaki Horie
- Hyperbaric Medical Center, University Hospital of Medicine, Tokyo Medical and Dental University, Tokyo; Japan
| | - Mitsuhiro Enomoto
- Hyperbaric Medical Center, University Hospital of Medicine, Tokyo Medical and Dental University, Tokyo; Japan
| | - Manabu Shimoda
- Hyperbaric Medical Center, University Hospital of Medicine, Tokyo Medical and Dental University, Tokyo; Japan
| | - Atsushi Okawa
- Department of Orthopaedic Surgery, Graduate School, Tokyo Medical and Dental University, Tokyo, Japan; and
| | - Shumpei Miyakawa
- Division of Sports Medicine, Graduate School of Comprehensive Human Sciences, University of Tsukuba, Tsukuba, Japan
| | - Kazuyoshi Yagishita
- Hyperbaric Medical Center, University Hospital of Medicine, Tokyo Medical and Dental University, Tokyo; Japan
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49
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Sobrian SK, Walters E. Enhanced Satellite Cell Activity in Aging Skeletal Muscle after Manual Acupuncture-Induced Injury. Chin Med 2014. [DOI: 10.4236/cm.2014.51004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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50
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Abstract
Skeletal muscle continuously adapts to changes in its mechanical environment through modifications in gene expression and protein stability that affect its physiological function and mass. However, mechanical stresses commonly exceed the parameters that induce adaptations, producing instead acute injury. Furthermore, the relatively superficial location of many muscles in the body leaves them further vulnerable to acute injuries by exposure to extreme temperatures, contusions, lacerations or toxins. In this article, the molecular, cellular, and mechanical factors that underlie muscle injury and the capacity of muscle to repair and regenerate are presented. Evidence shows that muscle injuries that are caused by eccentric contractions result from direct mechanical damage to myofibrils. However, muscle pathology following other acute injuries is largely attributable to damage to the muscle cell membrane. Many feaures in the injury-repair-regeneration cascade relate to the unregulated influx of calcium through membrane lesions, including: (i) activation of proteases and hydrolases that contribute muscle damage, (ii) activation of enzymes that drive the production of mitogens and motogens for muscle and immune cells involved in injury and repair, and (iii) enabling protein-protein interactions that promote membrane repair. Evidence is also presented to show that the myogenic program that is activated by acute muscle injury and the inflammatory process that follows are highly coordinated, with myeloid cells playing a central role in modulating repair and regeneration. The early-invading, proinflammatory M1 macrophages remove debris caused by injury and express Th1 cytokines that play key roles in regulating the proliferation, migration, and differentiation of satellite cells. The subsequent invasion by anti-inflammatory, M2 macrophages promotes tissue repair and attenuates inflammation. Although this system provides an effective mechanism for muscle repair and regeneration following acute injury, it is dysregulated in chronic injuries. In this article, the process of muscle injury, repair and regeneration that occurs in muscular dystrophy is used as an example of chronic muscle injury, to highlight similarities and differences between the injury and repair processes that occur in acutely and chronically injured muscle.
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Affiliation(s)
- James G Tidball
- Molecular, Cellular & Integrative Physiology Program, University of California, Los Angeles, California, USA.
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