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The FEBS Journal Sep 2013There is currently no cure for muscular dystrophies, although several promising strategies are in basic and clinical research. One such strategy is cell transplantation... (Review)
Review
There is currently no cure for muscular dystrophies, although several promising strategies are in basic and clinical research. One such strategy is cell transplantation with satellite cells (or their myoblast progeny) to repair damaged muscle and provide dystrophin protein with the aim of preventing subsequent myofibre degeneration and repopulating the stem cell niche for future use. The present review aims to cover recent advances in satellite cell/myoblast therapy and to discuss the challenges that remain for it to become a realistic therapy.
Topics: Animals; Graft Survival; Humans; Muscular Dystrophies; Myoblasts; Satellite Cells, Skeletal Muscle
PubMed: 23560812
DOI: 10.1111/febs.12273 -
Cells Nov 2022Diabetic myopathy is a co-morbidity diagnosed in most diabetes mellitus patients, yet its pathogenesis is still understudied, which hinders the development of effective...
Diabetic myopathy is a co-morbidity diagnosed in most diabetes mellitus patients, yet its pathogenesis is still understudied, which hinders the development of effective therapies. This project aimed to investigate the effect of hyperglycemia on human myoblast physiology, devoid of other complicating factors, by utilizing human myoblasts derived from induced pluripotent stem cells (iPSCs), in a defined in vitro system. IPSC-derived myoblasts were expanded under three glucose conditions: low (5 mM), medium (17.5 mM) or high (25 mM). While hyperglycemic myoblasts demonstrated upregulation of Glut4 relative to the euglycemic control, myoblast proliferation demonstrated a glucose dose-dependent impedance. Further cellular analysis revealed a retarded cell cycle progression trapped at the S phase and G2/M phase and an impaired mitochondrial function in hyperglycemic myoblasts. Terminal differentiation of these hyperglycemic myoblasts resulted in significantly hypertrophic and highly branched myotubes with disturbed myosin heavy chain arrangement. Lastly, functional assessment of these myofibers derived from hyperglycemic myoblasts demonstrated comparatively increased fatigability. Collectively, the hyperglycemic myoblasts demonstrated deficient muscle regeneration capability and functionality, which falls in line with the sarcopenia symptoms observed in diabetic myopathy patients. This human-based iPSC-derived skeletal muscle hyperglycemic model provides a valuable platform for mechanistic investigation of diabetic myopathy and therapeutic development.
Topics: Humans; Induced Pluripotent Stem Cells; Myoblasts; Muscle, Skeletal; Hyperglycemia; Cell Proliferation; Glucose
PubMed: 36429100
DOI: 10.3390/cells11223674 -
Experimental Cell Research Dec 2020A large number of intracellular proteins are degraded by the ubiquitin-proteasome system, one of the major protein degradation pathways. It produces peptides of several...
A large number of intracellular proteins are degraded by the ubiquitin-proteasome system, one of the major protein degradation pathways. It produces peptides of several different sizes through protein degradation, and these peptides are rapidly degraded into free amino acids by various intracellular aminopeptidases. Previously, we reported that the activity of proteasomes and aminopeptidases in the proteolysis pathway are necessary for myoblast proliferation and differentiation. However, the detailed function of intracellular aminopeptidases in myoblast proliferation and differentiation has not yet been elucidated. In this study, we focused on alanine aminopeptidase (APN) and investigated the function of APN in C2C12 myoblast proliferation and differentiation. In myoblasts and myotubes, APN was mainly localized in the cell membrane as well as expressed at low levels in the cytoplasm and nucleus. The reduction of the APN enzymatic activity impaired the cell cycle progression in C2C12 myoblasts. In addition, apoptosis was induced after APN-knockdown. Finally, myogenic differentiation was also delayed in the APN-suppressed myoblasts. These findings indicate that APN is required for myoblast proliferation and differentiation.
Topics: Animals; Apoptosis; CD13 Antigens; Cell Differentiation; Cell Proliferation; Mice; Myoblasts; RNA, Small Interfering
PubMed: 33091420
DOI: 10.1016/j.yexcr.2020.112337 -
Scientific Reports Jul 2017The overall objective of the study was to identify mechanisms through which intercellular adhesion molecule-1 (ICAM-1) augments the adhesive and fusogenic properties of...
The overall objective of the study was to identify mechanisms through which intercellular adhesion molecule-1 (ICAM-1) augments the adhesive and fusogenic properties of myogenic cells. Hypotheses were tested using cultured myoblasts and fibroblasts, which do not constitutively express ICAM-1, and myoblasts and fibroblasts forced to express full length ICAM-1 or a truncated form lacking the cytoplasmic domain of ICAM-1. ICAM-1 mediated myoblast adhesion and fusion were quantified using novel assays and cell mixing experiments. We report that ICAM-1 augments myoblast adhesion to myoblasts and myotubes through homophilic trans-interactions. Such adhesive interactions enhanced levels of active Rac in adherent and fusing myoblasts, as well as triggered lamellipodia, spreading, and fusion of myoblasts through the signaling function of the cytoplasmic domain of ICAM-1. Rac inhibition negated ICAM-1 mediated lamellipodia, spreading, and fusion of myoblasts. The fusogenic property of ICAM-1-ICAM-1 interactions was restricted to myogenic cells, as forced expression of ICAM-1 by fibroblasts did not augment their fusion to ICAM-1+ myoblasts/myotubes. We conclude that ICAM-1 augments myoblast adhesion and fusion through its ability to self-associate and initiate Rac-mediated remodeling of the actin cytoskeleton.
Topics: Actin Cytoskeleton; Animals; Cell Adhesion; Cell Communication; Cell Fusion; Cell Line; Cell Movement; Fibroblasts; Fibronectins; Humans; Intercellular Adhesion Molecule-1; Laminin; Mice; Muscle Development; Myoblasts; Protein Binding; Protein Domains; Pseudopodia; rac GTP-Binding Proteins
PubMed: 28698658
DOI: 10.1038/s41598-017-05283-3 -
Toxins Apr 2022Uremic sarcopenia is a serious clinical problem associated with physical disability and increased morbidity and mortality. Methylglyoxal (MG) is a highly reactive,...
Uremic sarcopenia is a serious clinical problem associated with physical disability and increased morbidity and mortality. Methylglyoxal (MG) is a highly reactive, dicarbonyl uremic toxin that accumulates in the circulatory system in patients with chronic kidney disease (CKD) and is related to the pathology of uremic sarcopenia. The pathophysiology of uremic sarcopenia is multifactorial; however, the details remain unknown. We investigated the mechanisms of MG-induced muscle atrophy using mouse myoblast C2C12 cells, focusing on intracellular metabolism and mitochondrial injury. We found that one of the causative pathological mechanisms of uremic sarcopenia is metabolic flow change to fatty acid synthesis with MG-induced ATP shortage in myoblasts. Evaluation of cell viability revealed that MG showed toxic effects only in myoblast cells, but not in myotube cells. Expression of mRNA or protein analysis revealed that MG induces muscle atrophy, inflammation, fibrosis, and oxidative stress in myoblast cells. Target metabolomics revealed that MG induces metabolic alterations, such as a reduction in tricarboxylic acid cycle metabolites. In addition, MG induces mitochondrial morphological abnormalities in myoblasts. These changes resulted in the reduction of ATP derived from the mitochondria of myoblast cells. Our results indicate that MG is a pathogenic factor in sarcopenia in CKD.
Topics: Adenosine Triphosphate; Animals; Female; Humans; Indican; Inflammation; Male; Mice; Muscular Atrophy; Myoblasts; Oxidative Stress; Pyruvaldehyde; Renal Insufficiency, Chronic; Sarcopenia
PubMed: 35448872
DOI: 10.3390/toxins14040263 -
Cell Death & Disease Oct 2016Skeletal myogenesis is coordinated by multiple signaling pathways that control cell adhesion/migration, survival and differentiation accompanied by muscle-specific gene...
Skeletal myogenesis is coordinated by multiple signaling pathways that control cell adhesion/migration, survival and differentiation accompanied by muscle-specific gene expression. A cell surface protein Cdo is involved in cell contact-mediated promyogenic signals through activation of p38MAPK and AKT. Protein kinase C-related kinase 2 (PKN2/PRK2) is implicated in regulation of various biological processes, including cell migration, adhesion and death. It has been shown to interact with and inhibit AKT thereby inducing cell death. This led us to investigate the role of PKN2 in skeletal myogenesis and the crosstalk between PKN2 and Cdo. Like Cdo, PKN2 was upregulated in C2C12 myoblasts during differentiation and decreased in cells with Cdo depletion caused by shRNA or cultured on integrin-independent substratum. This decline of PKN2 levels resulted in diminished AKT activation during myoblast differentiation. Consistently, PKN2 overexpression-enhanced C2C12 myoblast differentiation, whereas PKN2-depletion impaired it, without affecting cell survival. PKN2 formed complexes with Cdo, APPL1 and AKT via its C-terminal region and this interaction appeared to be important for induction of AKT activity as well as myoblast differentiation. Furthermore, PKN2-enhanced MyoD-responsive reporter activities by mediating the recruitment of BAF60c and MyoD to the myogenin promoter. Taken together, PKN2 has a critical role in cell adhesion-mediated AKT activation during myoblast differentiation.
Topics: Adaptor Proteins, Signal Transducing; Animals; Cell Adhesion Molecules; Cell Differentiation; Cell Line; Enzyme Activation; Genes, Reporter; Mice; MyoD Protein; Myoblasts; Protein Binding; Protein Kinase C; Proto-Oncogene Proteins c-akt; Two-Hybrid System Techniques; Up-Regulation
PubMed: 27763641
DOI: 10.1038/cddis.2016.296 -
Genes Jun 2023The processes of muscle growth and development, including myoblast proliferation, migration, differentiation, and fusion, are modified by a variety of regulatory...
The processes of muscle growth and development, including myoblast proliferation, migration, differentiation, and fusion, are modified by a variety of regulatory factors. plays an important role in atrial development, atrial cardiomyopathy, muscle-fiber size, and muscle development. The structural variation (SV) of was found via the de novo sequencing of Ningxiang pigs, and the existence of SV was verified in the experiments. The genotype distribution of Ningxiang pigs and Large White pigs was detected, and it was found that Ningxiang pigs were mainly of the genotype and that Large White pigs were mainly of the genotype. However, the molecular mechanisms behind the -mediated regulation of skeletal muscle development need to be deeply explored. Therefore, RT-qPCR, 3'RACE, CCK8, EdU, Western blot, immunofluorescence, flow cytometry, and bioinformation analysis were used to explore the function of in myoblast development. The cDNA of was successfully cloned from Ningxiang pigs, and its physicochemical properties were predicted. The expression profiles in six tissues and four stages of Ningxiang pigs and Large White pigs were found to be the highest in the lungs and 30 days after birth. The expression of increased gradually with the extension of the myogenic differentiation time. The myoblast function test showed that the overexpression of inhibited proliferation and promoted apoptosis and differentiation. The knockdown of showed the opposite result. These results enhance our understanding of the molecular mechanisms of muscle development and provide a solid theoretical foundation for further exploring the role of the gene in muscle development.
Topics: Animals; Swine; Atrial Fibrillation; Myoblasts; Muscle Development
PubMed: 37372447
DOI: 10.3390/genes14061267 -
EMBO Reports Apr 2018Mitochondria are the energy-generating hubs of the cell. In spite of considerable advances, our understanding of the factors that regulate the molecular circuits that...
Mitochondria are the energy-generating hubs of the cell. In spite of considerable advances, our understanding of the factors that regulate the molecular circuits that govern mitochondrial function remains incomplete. Using a genome-wide functional screen, we identify the poorly characterized protein Zinc finger CCCH-type containing 10 (Zc3h10) as regulator of mitochondrial physiology. We show that Zc3h10 is upregulated during physiological mitochondriogenesis as it occurs during the differentiation of myoblasts into myotubes. Zc3h10 overexpression boosts mitochondrial function and promotes myoblast differentiation, while the depletion of Zc3h10 results in impaired myoblast differentiation, mitochondrial dysfunction, reduced expression of electron transport chain (ETC) subunits, and blunted TCA cycle flux. Notably, we have identified a loss-of-function mutation of Zc3h10 in humans (Tyr105 to Cys105) that is associated with increased body mass index, fat mass, fasting glucose, and triglycerides. Isolated peripheral blood mononuclear cells from individuals homozygotic for Cys105 display reduced oxygen consumption rate, diminished expression of some ETC subunits, and decreased levels of some TCA cycle metabolites, which all together derive in mitochondrial dysfunction. Taken together, our study identifies Zc3h10 as a novel mitochondrial regulator.
Topics: Aged; Animals; Carrier Proteins; Cell Differentiation; Cell Line; Citric Acid Cycle; Computational Biology; Energy Metabolism; Female; Gene Expression; Gene Expression Profiling; Gene Silencing; Humans; Male; Mice; Mitochondria; Muscle Fibers, Skeletal; Muscle, Skeletal; Mutation; Myoblasts; Proteome; Proteomics
PubMed: 29507079
DOI: 10.15252/embr.201745531 -
International Journal of Molecular... Jan 2022Skeletal myogenesis is essential for the maintenance of muscle quality and quantity, and impaired myogenesis is intimately associated with muscle wasting diseases....
Skeletal myogenesis is essential for the maintenance of muscle quality and quantity, and impaired myogenesis is intimately associated with muscle wasting diseases. Although microRNA (miRNA) plays a crucial role in myogenesis and relates to muscle wasting in obesity, the molecular targets and roles of miRNAs modulated by saturated fatty acids (SFA) are largely unknown. In the present study, we investigated the role of miR-320-3p on the differentiation of myogenic progenitor cells. Palmitic acid (PA), the most abundant dietary SFA, suppressed myogenic factors expression and impaired differentiation in C2C12 myoblasts, and these effects were accompanied by CFL2 downregulation and miR-320-3p upregulation. In particular, miR-320-3p appeared to target mRNA directly and suppress the expression of CFL2, an essential factor for filamentous actin (F-actin) depolymerization. Transfection of myoblasts with miR-320-3p mimic increased F-actin formation and nuclear translocation of Yes-associated protein 1 (YAP1), a key component of mechanotransduction. Furthermore, miR-320-3p mimic increased myoblast proliferation and markedly impeded the expression of MyoD and MyoG, consequently inhibiting myoblast differentiation. In conclusion, our current study highlights the role of miR-320-3p on CFL2 expression, YAP1 activation, and myoblast differentiation and suggests that PA-inducible miR-320-3p is a significant mediator of muscle wasting in obesity.
Topics: 3' Untranslated Regions; Actins; Animals; Cell Differentiation; Cell Line; Cell Proliferation; Fluorescent Antibody Technique; Gene Expression Regulation; Mice; MicroRNAs; Muscle Development; Myoblasts; RNA Interference; RNA, Messenger; YAP-Signaling Proteins
PubMed: 35054986
DOI: 10.3390/ijms23020801 -
International Journal of Molecular... Jan 2020Skeletal muscle is constantly renewed in response to injury, exercise, or muscle diseases. Muscle stem cells, also known as satellite cells, are stimulated by local...
Skeletal muscle is constantly renewed in response to injury, exercise, or muscle diseases. Muscle stem cells, also known as satellite cells, are stimulated by local damage to proliferate extensively and form myoblasts that then migrate, differentiate, and fuse to form muscle fibers. The transmembrane heparan sulfate proteoglycan syndecan-4 plays multiple roles in signal transduction processes, such as regulating the activity of the small GTPase Rac1 (Ras-related C3 botulinum toxin substrate 1) by binding and inhibiting the activity of Tiam1 (T-lymphoma invasion and metastasis-1), a guanine nucleotide exchange factor for Rac1. The Rac1-mediated actin remodeling is required for cell migration. Syndecan-4 knockout mice cannot regenerate injured muscle; however, the detailed underlying mechanism is unknown. Here, we demonstrate that shRNA-mediated knockdown of syndecan-4 decreases the random migration of mouse myoblasts during live-cell microscopy. Treatment with the Rac1 inhibitor NSC23766 did not restore the migration capacity of syndecan-4 silenced cells; in fact, it was further reduced. Syndecan-4 knockdown decreased the directional persistence of migration, abrogated the polarized, asymmetric distribution of Tiam1, and reduced the total Tiam1 level of the cells. Syndecan-4 affects myoblast migration via its role in expression and localization of Tiam1; this finding may facilitate greater understanding of the essential role of syndecan-4 in the development and regeneration of skeletal muscle.
Topics: Animals; Cell Line; Cell Movement; Gene Expression Regulation; Gene Knockdown Techniques; Mice; Myoblasts; Syndecan-4; T-Lymphoma Invasion and Metastasis-inducing Protein 1
PubMed: 32012800
DOI: 10.3390/ijms21030823