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International Journal of Biological... May 2010Adult skeletal muscle stem cells, termed satellite cells are imperative to muscle regeneration. Much work has been performed on satellite cell identification and the... (Review)
Review
Adult skeletal muscle stem cells, termed satellite cells are imperative to muscle regeneration. Much work has been performed on satellite cell identification and the subsequent activation of the myogenic response but the regulation of satellite cells including its activation is not well elucidated. The purpose of this review article is to synthesize what the literature reveals in regards to the current understanding of satellite cells including their contribution to muscle repair and growth following physiological stimuli. In addition, this review article will describe the recent findings on the roles of the classic developmental signaling pathways, Notch and Wnt, to the myogenic response in various muscle injury models. This purpose of this summary is to bring awareness of the impact that muscle contraction models have on the local and systemic environment of adult muscle stem cells which will be beneficial for comprehending and treatment development for muscle -associated ailments and other organ diseases.
Topics: Animals; Humans; Muscle Development; Muscle, Skeletal; Muscular Diseases; Myoblasts; Satellite Cells, Perineuronal; Signal Transduction
PubMed: 20567496
DOI: 10.7150/ijbs.6.268 -
Cold Spring Harbor Perspectives in... Feb 2017Development of skeletal muscle is a multistage process that includes lineage commitment of multipotent progenitor cells, differentiation and fusion of myoblasts into... (Review)
Review
Development of skeletal muscle is a multistage process that includes lineage commitment of multipotent progenitor cells, differentiation and fusion of myoblasts into multinucleated myofibers, and maturation of myofibers into distinct types. Lineage-specific transcriptional regulation lies at the core of this process, but myogenesis is also regulated by extracellular cues. Some of these cues are initiated by direct cell-cell contact between muscle precursor cells themselves or between muscle precursors and cells of other lineages. Examples of the latter include interaction of migrating neural crest cells with multipotent muscle progenitor cells, muscle interstitial cells with myoblasts, and neurons with myofibers. Among the signaling factors involved are Notch ligands and receptors, cadherins, Ig superfamily members, and Ephrins and Eph receptors. In this article we describe recent progress in this area and highlight open questions raised by the findings.
Topics: Animals; Cell Differentiation; Cell Fusion; Cell Lineage; Humans; Muscle Development; Muscle, Skeletal
PubMed: 28062562
DOI: 10.1101/cshperspect.a029298 -
The International Journal of... 2017Several different models of myogenesis describing early stages of amphibian paraxial myotomal myogenesis are known. Myoblasts of Xenopus laevis and Hymenochirus... (Review)
Review
Several different models of myogenesis describing early stages of amphibian paraxial myotomal myogenesis are known. Myoblasts of Xenopus laevis and Hymenochirus boettgeri change their position from perpendicular to parallel, in relation to axial organs, and differentiate into mononucleate myotubes. In Bombina variegate the myotomal myoblasts change their shape from round to elongate and then differentiate into mononuclear, morphologically mature myotubes. In Pelobates fuscus and Triturus vulgaris, myoblasts fuse into multinuclear myotubes. Mono- and multinucleate myotubes achieve morphological maturity during the differentiation process. During myogenesis of B. variegata, the nuclei of mononucleate, differentiating myotubes contain a tetraploid quantity of DNA (4C DNA). The stable quantity of DNA is confirmed by lack of H-thimidine incorporation into myotube nuclei. This outcome is a proof that myoblasts withdraw from the cell cycle in the G2 phase. The further development of myotomal myotubes involves myoblasts of mesenchymal origin. These myoblasts fuse with myotubes in X. laevis and B. variegate in the G1 phase. Secondary muscle fibres in amphibian myotomes have only mesenchymal origin. Mesenchymal myoblasts fuse into multinucleated myotubes. Myofibril development in the differentiating myotube and lack of DNA replication confirm the classical paradigm of myogenesis. Mesenchymal myoblasts are taking part in the myogenesis of musculus rectus abdominis and limb muscles. The mesenchymal cells in the myogenesis process show one model of myogenesis, which is a classical model of myogenesis. The mesenchymal cells probably come from dermatome.
Topics: Animals; Anura; Cell Division; Mesoderm; Muscle Development; Muscle, Skeletal; Myoblasts
PubMed: 28287243
DOI: 10.1387/ijdb.160370mm -
The FEBS Journal Sep 2013The transcriptional regulatory network that controls the determination and differentiation of skeletal muscle cells in the embryo has at its core the four myogenic... (Review)
Review
The transcriptional regulatory network that controls the determination and differentiation of skeletal muscle cells in the embryo has at its core the four myogenic regulatory factors (MRFs) Myf5, MyoD, Mrf4 and MyoG. These basic helix-loop-helix transcription factors act by binding, as obligate heterodimers with the ubiquitously expressed E proteins, to the E-box sequence CANNTG. While all skeletal muscle cells have the same underlying function their progenitors arise at many sites in the embryo and it has become apparent that the upstream activators of the cascade differ in these various populations so that it can be switched on by a variety of inductive signals, some of which act by initiating transcription, some by maintaining it. The application of genome-wide approaches has provided important new information as to how the MRFs function to activate the terminal differentiation programme and some of these data provide significant mechanistic insights into questions which have exercised the field for many years. We also consider the emerging roles played by micro-RNAs in the regulation of both upstream activators and terminal differentiation genes.
Topics: Animals; Cell Differentiation; Humans; Muscle Development; Muscles; Myogenic Regulatory Factors
PubMed: 23751110
DOI: 10.1111/febs.12379 -
Journal of Neuromuscular Diseases 2021The resident stem cell for skeletal muscle is the satellite cell. On the 50th anniversary of its discovery in 1961, we described the history of skeletal muscle research... (Review)
Review
The resident stem cell for skeletal muscle is the satellite cell. On the 50th anniversary of its discovery in 1961, we described the history of skeletal muscle research and the seminal findings made during the first 20 years in the life of the satellite cell (Scharner and Zammit 2011, doi: 10.1186/2044-5040-1-28). These studies established the satellite cell as the source of myoblasts for growth and regeneration of skeletal muscle. Now on the 60th anniversary, we highlight breakthroughs in the second phase of satellite cell research from 1980 to 2000. These include technical innovations such as isolation of primary satellite cells and viable muscle fibres complete with satellite cells in their niche, together with generation of many useful reagents including genetically modified organisms and antibodies still in use today. New methodologies were combined with description of endogenous satellite cells markers, notably Pax7. Discovery of the muscle regulatory factors Myf5, MyoD, myogenin, and MRF4 in the late 1980s revolutionized understanding of the control of both developmental and regerenative myogenesis. Emergence of genetic lineage markers facilitated identification of satellite cells in situ, and also empowered transplantation studies to examine satellite cell function. Finally, satellite cell heterogeneity and the supportive role of non-satellite cell types in muscle regeneration were described. These major advances in methodology and in understanding satellite cell biology provided further foundations for the dramatic escalation of work on muscle stem cells in the 21st century.
Topics: Animals; Cell Differentiation; History, 20th Century; History, 21st Century; Humans; Mice; Muscle Development; Muscle, Skeletal; Myogenic Regulatory Factors; Myogenin; PAX7 Transcription Factor; Satellite Cells, Skeletal Muscle
PubMed: 34459412
DOI: 10.3233/JND-210705 -
Cells Apr 2022MyoD, Myf5, myogenin, and MRF4 (also known as Myf6 or herculin) are myogenic regulatory factors (MRFs). MRFs are regarded as master transcription factors that are... (Review)
Review
MyoD, Myf5, myogenin, and MRF4 (also known as Myf6 or herculin) are myogenic regulatory factors (MRFs). MRFs are regarded as master transcription factors that are upregulated during myogenesis and influence stem cells to differentiate into myogenic lineage cells. In this review, we summarize MRFs, their regulatory factors, such as TLE3, NF-κB, and MRF target genes, including non-myogenic genes such as taste receptors. Understanding the function of MRFs and the physiology or pathology of satellite cells will contribute to the development of cell therapy and drug discovery for muscle-related diseases.
Topics: Muscle Development; Muscle, Skeletal; MyoD Protein; Myogenic Regulatory Factors; Stem Cells
PubMed: 35563799
DOI: 10.3390/cells11091493 -
International Journal of Molecular... Aug 2023Injury to skeletal muscle through trauma, physical activity, or disease initiates a process called muscle regeneration. When injured myofibers undergo necrosis, muscle... (Review)
Review
Injury to skeletal muscle through trauma, physical activity, or disease initiates a process called muscle regeneration. When injured myofibers undergo necrosis, muscle regeneration gives rise to myofibers that have myonuclei in a central position, which contrasts the normal, peripheral position of myonuclei. Myofibers with central myonuclei are called regenerating myofibers and are the hallmark feature of muscle regeneration. An important and underappreciated aspect of muscle regeneration is the maturation of regenerating myofibers into a normal sized myofiber with peripheral myonuclei. Strikingly, very little is known about processes that govern regenerating myofiber maturation after muscle injury. As knowledge of myofiber formation and maturation during embryonic, fetal, and postnatal development has served as a foundation for understanding muscle regeneration, this narrative review discusses similarities and differences in myofiber maturation during muscle development and regeneration. Specifically, we compare and contrast myonuclear positioning, myonuclear accretion, myofiber hypertrophy, and myofiber morphology during muscle development and regeneration. We also discuss regenerating myofibers in the context of different types of myofiber necrosis (complete and segmental) after muscle trauma and injurious contractions. The overall goal of the review is to provide a framework for identifying cellular and molecular processes of myofiber maturation that are unique to muscle regeneration.
Topics: Humans; Muscle, Skeletal; Exercise; Hypertrophy; Muscle Development; Necrosis
PubMed: 37628725
DOI: 10.3390/ijms241612545 -
Biomedicine & Pharmacotherapy =... Sep 2023Cordycepin (with a molecular formula of CHNO), a natural adenosine isolated from Cordyceps militaris, has an important regulatory effect on skeletal muscle remodelling...
Cordycepin (with a molecular formula of CHNO), a natural adenosine isolated from Cordyceps militaris, has an important regulatory effect on skeletal muscle remodelling and quality maintenance. The aim of this study was to investigate the effect of cordycepin on myoblast differentiation and explore the underlying molecular mechanisms of this effect. Our results showed that cordycepin inhibited myogenesis by downregulating myogenic differentiation (MyoD) and myogenin (MyoG), preserved undifferentiated reserve cell pools by upregulating myogenic factor 5 (Myf5) and retinoblastoma-like protein p130 (p130), and enhanced energy reserves by decreasing intracellular reactive oxygen species (ROS) and enhancing mitochondrial membrane potential, mitochondrial mass, and ATP content. The effect of cordycepin on myogenesis was associated with increased phosphorylation of extracellular signal-regulated kinase 1/2 (p-ERK1/2). PD98059 (a specific inhibitor of p-ERK1/2) attenuated the inhibitory effect of cordycepin on C2C12 differentiation. The present study reveals that cordycepin inhibits myogenesis through ERK1/2 MAPK signalling activation accompanied by an increase in skeletal muscle energy reserves and improving skeletal muscle oxidative stress, which may have implications for its further application for the prevention and treatment of degenerative muscle diseases caused by the depletion of depleted muscle stem cells.
Topics: MAP Kinase Signaling System; Cell Differentiation; Deoxyadenosines; Muscle Development
PubMed: 37453196
DOI: 10.1016/j.biopha.2023.115163 -
Trends in Pharmacological Sciences Nov 2011Skeletal muscle development, repair and function are dependent on highly coordinated expression of many genes. RNA-binding proteins are crucial determinants of gene... (Review)
Review
Skeletal muscle development, repair and function are dependent on highly coordinated expression of many genes. RNA-binding proteins are crucial determinants of gene expression in the health and disease of various tissues, including skeletal muscle. A variety of RNA-binding proteins are associated with a transcript during its life cycle and define the lifetime, cellular localization, processing and rate at which that transcript is translated and ultimately degraded. The focus of this review is to highlight the roles of the best-characterized RNA-binding proteins in muscle, including HuR, KSRP, CUGBP1, PABPN1, Lin-28 and TTP. Recent studies indicate key functions for these RNA-binding proteins in different aspects of muscle physiology. Understanding the role of specific RNA-binding proteins in skeletal muscle will provide insights not only into basic mechanisms regulating gene expression in muscle, but also into the etiology and pathology of muscle disease.
Topics: Cell Differentiation; ELAV Proteins; Gene Expression Regulation; Humans; Muscle Development; Muscles; RNA-Binding Proteins
PubMed: 21982546
DOI: 10.1016/j.tips.2011.06.004 -
Bioscience Reports Feb 2018Despite the emerging importance of protein arginine methyltransferases (PRMTs) in regulating skeletal muscle plasticity, PRMT biology during muscle development is...
Despite the emerging importance of protein arginine methyltransferases (PRMTs) in regulating skeletal muscle plasticity, PRMT biology during muscle development is complex and not completely understood. Therefore, our purpose was to investigate PRMT1, -4, and -5 expression and function in skeletal muscle cells during the phenotypic remodeling elicited by myogenesis. CC muscle cell maturation, assessed during the myoblast (MB) stage, and during days 1, 3, 5, and 7 of differentiation, was employed as an model of myogenesis. We observed PRMT-specific patterns of expression and activity during myogenesis. PRMT4 and -5 gene expression was unchanged, while mRNA and protein content were significantly induced. Cellular monomethylarginines (MMAs) and symmetric dimethylarginines (SDMAs), indicative of global and type II PRMT activities, respectively, remained steady during development, while type I PRMT activity indicator asymmetric dimethylarginines (ADMAs) increased through myogenesis. Histone 4 arginine 3 (H4R3) and H3R17 contents were elevated coincident with the myonuclear accumulation of PRMT1 and -4. Collectively, this suggests that PRMTs are methyl donors throughout myogenesis and demonstrate specificity for their protein targets. Cells were then treated with TC-E 5003 (TC-E), a selective inhibitor of PRMT1 in order to specifically examine the enzymes role during myogenic differentiation. TC-E treated cells exhibited decrements in muscle differentiation, which were consistent with attenuated mitochondrial biogenesis and respiratory function. In summary, the present study increases our understanding of PRMT1, -4, and -5 biology during the plasticity of skeletal muscle development. Our results provide evidence for a role of PRMT1, via a mitochondrially mediated mechanism, in driving the muscle differentiation program.
Topics: Animals; Arginine; Cell Differentiation; Gene Expression Regulation, Developmental; Histones; Mice; Muscle Cells; Muscle Development; Muscle Fibers, Skeletal; Muscle, Skeletal; Protein-Arginine N-Methyltransferases
PubMed: 29208765
DOI: 10.1042/BSR20171533