-
Biomedicine & Pharmacotherapy =... Jun 2023Skeletal muscle is the most extensive tissue in mammals, and they perform several functions; it is derived from paraxial mesodermal somites and undergoes hyperplasia and... (Review)
Review
Skeletal muscle is the most extensive tissue in mammals, and they perform several functions; it is derived from paraxial mesodermal somites and undergoes hyperplasia and hypertrophy to form multinucleated, contractile, and functional muscle fibers. Skeletal muscle is a complex heterogeneous tissue composed of various cell types that establish communication strategies to exchange biological information; therefore, characterizing the cellular heterogeneity and transcriptional signatures of skeletal muscle is central to understanding its ontogeny's details. Studies of skeletal myogenesis have focused primarily on myogenic cells' proliferation, differentiation, migration, and fusion and ignored the intricate network of cells with specific biological functions. The rapid development of single-cell sequencing technology has recently enabled the exploration of skeletal muscle cell types and molecular events during development. This review summarizes the progress in single-cell RNA sequencing and its applications in skeletal myogenesis, which will provide insights into skeletal muscle pathophysiology.
Topics: Animals; Muscle, Skeletal; Muscle Fibers, Skeletal; Cell Differentiation; Mammals; Muscle Development; Developmental Biology; Sequence Analysis, RNA
PubMed: 37003036
DOI: 10.1016/j.biopha.2023.114631 -
Autophagy Sep 2019Macroautophagy/autophagy is a degradative process essential for various cellular processes. We previously demonstrated that autophagy-deficiency causes myoblast...
Macroautophagy/autophagy is a degradative process essential for various cellular processes. We previously demonstrated that autophagy-deficiency causes myoblast apoptosis and impairs myotube formation. In this study, we continued this work with particular emphasis on mitochondrial remodelling and stress/apoptotic signaling. We found increased (p < 0.05) autophagic (e.g., altered LC3B levels, increased ATG7, decreased SQSTM1) and mitophagic (e.g., BNIP3 upregulation, mitochondrial localized GFP-LC3 puncta, and elevated mitochondrial LC3B-II) signaling during myoblast differentiation. shRNA-mediated knockdown of ATG7 (sh) decreased these autophagic and mitophagic responses, while increasing CASP3 activity and ANXA5/annexin V staining in differentiating myoblasts; ultimately resulting in dramatically impaired myogenesis. Further confirming the importance of mitophagy in these responses, CRISPR-Cas9-mediated knockout of () resulted in increased CASP3 activity and DNA fragmentation as well as impaired myoblast differentiation. In addition, sh myoblasts displayed greater endoplasmic reticulum (e.g., increased CAPN activity and HSPA) and mitochondrial (e.g., mPTP formation, reduced mitochondrial membrane potential, elevated mitochondrial 4-HNE) stress. sh and myoblasts also displayed altered mitochondria-associated signaling (e.g., PPARGC1A, DNM1L, OPA1) and protein content (e.g., SLC25A4, VDAC1, CYCS). Moreover, sh myoblasts displayed CYCS and AIFM1 release from mitochondria, and CASP9 activation. Similarly, myoblasts had significantly higher CASP9 activation during differentiation. Importantly, administration of a chemical inhibitor of CASP9 (Ac-LEHD-CHO) or dominant-negative CASP9 (ad-DNCASP9) partially recovered differentiation and myogenesis in sh myoblasts. Together, these data demonstrate an essential role for autophagy in protecting myoblasts from mitochondrial oxidative stress and apoptotic signaling during differentiation, as well as in the regulation of mitochondrial network remodelling and myogenesis. : 3MA: 3-methyladenine; 4-HNE: 4-hydroxynonenal; ACT: actin; AIFM1/AIF: apoptosis-inducing factor, mitochondrion-associated 1; ANXA5: annexin V; ATG7: autophagy related 7; AU: arbitrary units; BAX: BCL2-associated X protein; BCL2: B cell leukemia/lymphoma 2; BECN1: beclin 1, autophagy related; BNIP3: BCL2/adenovirus E1B interacting protein 3; CAPN: calpain; CASP: caspase; CASP3: caspase 3; CASP8: caspase 8; CASP9: caspase 9; CASP12: caspase 12; CAT: catalase; CQ: chloroquine; CYCS: cytochrome c, somatic; DCF; 2',7'-dichlorofluorescein; DNM1L/DRP1: dynamin 1-like; DM: differentiation media; DMEM: Dulbecco's modified Eagle's medium; ER: endoplasmic reticulum; GAPDH: glyceraldehyde-3-phosphate dehydrogenase; GFP: green fluorescent protein; GM: growth media; p-H2AFX: phosphorylated H2A histone family, member X; H2BFM: H2B histone family, member M; HBSS: Hanks balanced salt solution; HSPA/HSP70: heat shock protein family A; JC-1: tetraethylbenzimidazolylcarbocyanine iodide; MAP1LC3B/LC3B: microtubule-associated protein 1 light chain 3 beta; mPTP: mitochondrial permeability transition pore; MYH: myosin heavy chain; MYOG: myogenin; OPA1: OPA1, mitochondrial dynamin like GTPase; PI: propidium iodide; PINK1: PTEN induced putative kinase 1; PPARGC1A/PGC1α: peroxisome proliferative activated receptor, gamma, coactivator 1 alpha; ROS: reactive oxygen species; SLC25A4/ANT1: solute carrier family 25 (mitochondrial carrier, adenine nucleotide translocator), member 4; SOD1: superoxide dismutase 1, soluble; SOD2: superoxide dismutase 2, mitochondrial; SQSTM1/p62: sequestosome 1; VDAC1: voltage-dependent anion channel 1.
Topics: Animals; Apoptosis; Autophagy-Related Protein 7; Caspase 3; Caspase 9; Cell Differentiation; Cell Line; Endoplasmic Reticulum; Membrane Proteins; Mice; Microtubule-Associated Proteins; Mitochondria; Mitochondrial Proteins; Mitophagy; Muscle Development; Muscle, Skeletal; Myoblasts; Oxidative Stress; Reactive Oxygen Species
PubMed: 30859901
DOI: 10.1080/15548627.2019.1591672 -
The myogenic regulatory factors, determinants of muscle development, cell identity and regeneration.Seminars in Cell & Developmental Biology Dec 2017The Myogenic Regulatory Factors (MRFs) Myf5, MyoD, myogenin and MRF4 are members of the basic helix-loop-helix family of transcription factors that control the... (Review)
Review
The Myogenic Regulatory Factors (MRFs) Myf5, MyoD, myogenin and MRF4 are members of the basic helix-loop-helix family of transcription factors that control the determination and differentiation of skeletal muscle cells during embryogenesis and postnatal myogenesis. The dynamics of their temporal and spatial expression as well as their biochemical properties have allowed the identification of a precise and hierarchical relationship between the four MRFs. This relationship establishes the myogenic lineage as well as the maintenance of the terminal myogenic phenotype. The application of genome-wide technologies has provided important new information as to how the MRFs function to activate muscle gene expression. Application of combined functional genomics technologies along with single cell lineage tracing strategies will allow a deeper understanding of the mechanisms mediating myogenic determination, cell differentiation and muscle regeneration.
Topics: Animals; Cell Differentiation; Cell Lineage; Gene Expression Regulation, Developmental; Mice; Muscle Development; Muscle, Skeletal; Myogenic Regulatory Factors; Phylogeny; Regeneration
PubMed: 29127045
DOI: 10.1016/j.semcdb.2017.11.010 -
Cellular and Molecular Life Sciences :... Jul 2019Skeletal muscle regeneration is a finely tuned process involving the activation of various cellular and molecular processes. Satellite cells, the stem cells of skeletal... (Review)
Review
Skeletal muscle regeneration is a finely tuned process involving the activation of various cellular and molecular processes. Satellite cells, the stem cells of skeletal muscle, are indispensable for skeletal muscle regeneration. Their functionality is critically modulated by intrinsic signaling pathways as well as by interactions with the stem cell niche. Here, we discuss the properties of satellite cells, including heterogeneity regarding gene expression and/or their phenotypic traits and the contribution of satellite cells to skeletal muscle regeneration. We also summarize the process of regeneration with a specific emphasis on signaling pathways, cytoskeletal rearrangements, the importance of miRNAs, and the contribution of non-satellite cells such as immune cells, fibro-adipogenic progenitor cells, and PW1-positive/Pax7-negative interstitial cells.
Topics: Adult; Adult Stem Cells; Cell Differentiation; Humans; Muscle Development; Muscle, Skeletal; Regeneration
PubMed: 30976839
DOI: 10.1007/s00018-019-03093-6 -
Cell Proliferation Jul 2020Exosomes are membrane-bound extracellular vesicles that are produced in the endosomal compartment of most mammalian cell types and then released. Exosomes are effective... (Review)
Review
Exosomes are membrane-bound extracellular vesicles that are produced in the endosomal compartment of most mammalian cell types and then released. Exosomes are effective carriers for the intercellular material transfer of material that can influence a series of physiological and pathological processes in recipient cells. Among loaded cargoes, non-coding RNAs (ncRNAs) vary for the exosome-producing cell and its homeostatic state, and characterization of the biogenesis and secretion of exosomal ncRNAs and the functions of these ncRNAs in skeletal muscle myogenesis remain preliminary. In this review, we will describe what is currently known of exosome biogenesis, release and uptake of exosomal ncRNAs, as well as the varied functions of exosomal miRNAs in skeletal muscle myogenesis.
Topics: Animals; Exosomes; Humans; MicroRNAs; Muscle Development; Muscle, Skeletal
PubMed: 32578911
DOI: 10.1111/cpr.12857 -
Developmental Cell May 2022Rhabdomyosarcoma (RMS) is a pediatric cancer with features of skeletal muscle; patients with unresectable or metastatic RMS fare poorly due to high rates of disease...
Rhabdomyosarcoma (RMS) is a pediatric cancer with features of skeletal muscle; patients with unresectable or metastatic RMS fare poorly due to high rates of disease recurrence. Here, we use single-cell and single-nucleus RNA sequencing to show that RMS tumors recapitulate the spectrum of embryonal myogenesis. Using matched patient samples from a clinical trial and orthotopic patient-derived xenografts (O-PDXs), we show that chemotherapy eliminates the most proliferative component with features of myoblasts within embryonal RMS; after treatment, the immature population with features of paraxial mesoderm expands to reconstitute the developmental hierarchy of the original tumor. We discovered that this paraxial mesoderm population is dependent on EGFR signaling and is sensitive to EGFR inhibitors. Taken together, these data serve as a proof of concept that targeting each developmental state in embryonal RMS is an effective strategy for improving outcomes by preventing disease recurrence.
Topics: Child; Drug Resistance; ErbB Receptors; Humans; Muscle Development; Neoplasm Recurrence, Local; Rhabdomyosarcoma; Rhabdomyosarcoma, Embryonal
PubMed: 35483358
DOI: 10.1016/j.devcel.2022.04.003 -
Biochimica Et Biophysica Acta. Gene... Apr 2020Skeletal muscles have an immense ability to regenerate from the muscle stem cells called satellite cells. The process of skeletal muscle regeneration is called... (Review)
Review
Skeletal muscles have an immense ability to regenerate from the muscle stem cells called satellite cells. The process of skeletal muscle regeneration is called myogenesis, which starts with activation of quiescent satellite cells immediately after muscle injury followed by proliferation and fusion of myoblasts into myotubes. Myogenesis is orchestrated through the expression of a specific set of genes which, at each step regulated by complex gene regulatory networks. Besides the well-established roles of transcription factors, increasing evidence demonstrated that circular (circ)RNAs modulate gene expression during myogenesis and are involved in muscle-related diseases. Here we review the recent findings of circRNAs involved in myogenesis.
Topics: Animals; Gene Expression Regulation; Humans; MicroRNAs; Muscle Development; Muscle, Skeletal; RNA, Circular
PubMed: 30946990
DOI: 10.1016/j.bbagrm.2019.02.011 -
BMC Biology Feb 2023Skeletal muscle development is a multistep process whose understanding is central in a broad range of fields and applications, from the potential medical value to human...
BACKGROUND
Skeletal muscle development is a multistep process whose understanding is central in a broad range of fields and applications, from the potential medical value to human society, to its economic value associated with improvement of agricultural animals. Skeletal muscle initiates in the somites, with muscle precursor cells generated in the dermomyotome and dermomyotome-derived myotome before muscle differentiation ensues, a developmentally regulated process that is well characterized in model organisms. However, the regulation of skeletal muscle ontogeny during embryonic development remains poorly defined in farm animals, for instance in pig. Here, we profiled gene expression and chromatin accessibility in developing pig somites and myotomes at single-cell resolution.
RESULTS
We identified myogenic cells and other cell types and constructed a differentiation trajectory of pig skeletal muscle ontogeny. Along this trajectory, the dynamic changes in gene expression and chromatin accessibility coincided with the activities of distinct cell type-specific transcription factors. Some novel genes upregulated along the differentiation trajectory showed higher expression levels in muscular dystrophy mice than that in healthy mice, suggesting their involvement in myogenesis. Integrative analysis of chromatin accessibility, gene expression data, and in vitro experiments identified EGR1 and RHOB as critical regulators of pig embryonic myogenesis.
CONCLUSIONS
Collectively, our results enhance our understanding of the molecular and cellular dynamics in pig embryonic myogenesis and offer a high-quality resource for the further study of pig skeletal muscle development and human muscle disease.
Topics: Animals; Mice; Cell Differentiation; Chromatin; Chromatin Immunoprecipitation Sequencing; Gene Expression Regulation, Developmental; Muscle Development; Muscle, Skeletal; Single-Cell Analysis; Single-Cell Gene Expression Analysis; Swine
PubMed: 36726129
DOI: 10.1186/s12915-023-01519-z -
Journal of Cachexia, Sarcopenia and... Dec 2022Human pluripotent stem cell-derived muscle models show great potential for translational research. Here, we describe developmentally inspired methods for the derivation...
BACKGROUND
Human pluripotent stem cell-derived muscle models show great potential for translational research. Here, we describe developmentally inspired methods for the derivation of skeletal muscle cells and their utility in skeletal muscle tissue engineering with the aim to model skeletal muscle regeneration and dystrophy in vitro.
METHODS
Key steps include the directed differentiation of human pluripotent stem cells to embryonic muscle progenitors followed by primary and secondary foetal myogenesis into three-dimensional muscle. To simulate Duchenne muscular dystrophy (DMD), a patient-specific induced pluripotent stem cell line was compared to a CRISPR/Cas9-edited isogenic control line.
RESULTS
The established skeletal muscle differentiation protocol robustly and faithfully recapitulates critical steps of embryonic myogenesis in two-dimensional and three-dimensional cultures, resulting in functional human skeletal muscle organoids (SMOs) and engineered skeletal muscles (ESMs) with a regeneration-competent satellite-like cell pool. Tissue-engineered muscle exhibits organotypic maturation and function (up to 5.7 ± 0.5 mN tetanic twitch tension at 100 Hz in ESM). Contractile performance could be further enhanced by timed thyroid hormone treatment, increasing the speed of contraction (time to peak contraction) as well as relaxation (time to 50% relaxation) of single twitches from 107 ± 2 to 75 ± 4 ms (P < 0.05) and from 146 ± 6 to 100 ± 6 ms (P < 0.05), respectively. Satellite-like cells could be documented as largely quiescent PAX7 cells (75 ± 6% Ki67 ) located adjacent to muscle fibres confined under a laminin-containing basal membrane. Activation of the engineered satellite-like cell niche was documented in a cardiotoxin injury model with marked recovery of contractility to 57 ± 8% of the pre-injury force 21 days post-injury (P < 0.05 compared to Day 2 post-injury), which was completely blocked by preceding irradiation. Absence of dystrophin in DMD ESM caused a marked reduction of contractile force (-35 ± 7%, P < 0.05) and impaired expression of fast myosin isoforms resulting in prolonged contraction (175 ± 14 ms, P < 0.05 vs. gene-edited control) and relaxation (238 ± 22 ms, P < 0.05 vs. gene-edited control) times. Restoration of dystrophin levels by gene editing rescued the DMD phenotype in ESM.
CONCLUSIONS
We introduce human muscle models with canonical properties of bona fide skeletal muscle in vivo to study muscle development, maturation, disease and repair.
Topics: Humans; Muscular Dystrophy, Duchenne; Muscle, Skeletal; Muscle Development; Satellite Cells, Skeletal Muscle; Muscle Fibers, Skeletal
PubMed: 36254806
DOI: 10.1002/jcsm.13094 -
Epigenetics Mar 2021Histone variants regulate chromatin accessibility and gene transcription. Given their distinct properties and functions, histone varint substitutions allow for profound... (Review)
Review
Histone variants regulate chromatin accessibility and gene transcription. Given their distinct properties and functions, histone varint substitutions allow for profound alteration of nucleosomal architecture and local chromatin landscape. Skeletal myogenesis driven by the key transcription factor MyoD is characterized by precise temporal regulation of myogenic genes. Timed substitution of variants within the nucleosomes provides a powerful means to ensure sequential expression of myogenic genes. Indeed, growing evidence has shown H3.3, H2A.Z, macroH2A, and H1b to be critical for skeletal myogenesis. However, the relative importance of various histone variants and their associated chaperones in myogenesis is not fully appreciated. In this review, we summarize the role that histone variants play in altering chromatin landscape to ensure proper muscle differentiation. The temporal regulation and cross talk between histones variants and their chaperones in conjunction with other forms of epigenetic regulation could be critical to understanding myogenesis and their involvement in myopathies.
Topics: Chromatin; DNA Methylation; Epigenesis, Genetic; Histones; Muscle Development; Nucleosomes
PubMed: 32686575
DOI: 10.1080/15592294.2020.1795606