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Phytomedicine : International Journal... Jul 2024Senile osteoporosis (SOP) is an age-related systemic metabolic bone disorder. Previous studies have proved that Zhuang-Gu-Fang (ZGF) modulates myokines, stimulates...
BACKGROUND
Senile osteoporosis (SOP) is an age-related systemic metabolic bone disorder. Previous studies have proved that Zhuang-Gu-Fang (ZGF) modulates myokines, stimulates osteogenic differentiation, and mitigates osteoporosis.
OBJECTIVE
To elucidate the mechanism by which ZGF promotes osteogenic differentiation via myoblast and myoblast exosomal microRNAs (miRNAs) and investigate its potential implications in senile osteoporosis.
METHODS
Characterization of ZGF and ZGF serum using UHPLC-MS/MS. An alkaline phosphatase (ALP) activity assay and staining techniques were employed to corroborate the impacts of ZGF on the osteogenic differentiation of bone marrow-derived mesenchymal stem cells (BMSCs) via myoblasts. Subsequently, exosomes derived from myoblasts were isolated through ultracentrifugation. The effects of ZGF on the BMSCs' osteogenic differentiation were substantiated through ALP activity, alizarin red staining, and a quantitative real-time polymerase reaction system (qRT-PCR). Selected miRNAs were identified via high-throughput sequencing and subjected to differential expression analysis, and subsequently validated through qRT-PCR. The senescence-accelerated (SAMP6) mice were selected as the SOP models. qRT-PCR analyses were further conducted to confirm the expression levels of these selected miRNAs in the muscle and bone tissues of the SAMP6 mice, and the protein expression of osteogenesis-related transcription factors OCN and Osterix in its bone tissue was evaluated by immunofluorescence staining analysis (IF).
RESULTS
ZGF may enhance the osteogenic differentiation of BMSCs through myoblasts and myoblast-derived exosomes. High-throughput sequencing, differential expression analysis, and subsequent qRT-PCR validation identified four miRNAs that stood out due to their significant differential expression: miR-5100, miR-142a-3p, miR-126a-3p, miR-450b-5p and miR-669a-5p. Moreover, the mice experiment corroborated these findings, which revealed that ZGF not only up-regulated the expression of miR-5100, miR-450b-5p and miR-126a-3p in muscle and bone tissues but also concurrently down-regulated the expression of miR-669a-5p in these tissues. IF staining analysis indicated that ZGF can significantly increase the protein expression of the osteogenic transcription factors OCN and Osterix in the bone tissue of mice with SOP.
CONCLUSIONS
ZGF can promote osteogenic differentiation of osteoblasts, regulate bone metabolism, and thereby delay the process of SOP. Perhaps, its mechanism is to upregulate myoblast-derived exosomes miR-5100, miR-126a-3p, and miR-450b-5p or downregulate miR-669a-5p. This study reports for the first time that myoblast exosomes miR-669a-5p and miR-450b-5p are novel targets for the regulation of osteoblastic differentiation and the treatment of SOP.
Topics: Animals; MicroRNAs; Cell Differentiation; Exosomes; Osteogenesis; Mice; Osteoblasts; Myoblasts; Mesenchymal Stem Cells; Drugs, Chinese Herbal; Osteoporosis; Male
PubMed: 38795694
DOI: 10.1016/j.phymed.2024.155718 -
European Journal of Cell Biology Jun 2024The RAS-MAPK-pathway is aberrantly regulated in cancer and developmental diseases called RASopathies. While typically the impact of Ras on the proliferation of various...
The RAS-MAPK-pathway is aberrantly regulated in cancer and developmental diseases called RASopathies. While typically the impact of Ras on the proliferation of various cancer cell lines is assessed, it is poorly established how Ras affects cellular differentiation. Here we implement the C2C12 myoblast cell line to systematically study the effect of Ras mutants and Ras-pathway drugs on differentiation. We first provide evidence that a minor pool of Pax7+ progenitors replenishes a major pool of transit amplifying cells that are ready to differentiate. Our data indicate that Ras isoforms have distinct roles in the differentiating culture, where K-Ras depletion increases and H-Ras depletion decreases terminal differentiation. This assay could therefore provide significant new insights into Ras biology and Ras-driven diseases. In line with this, we found that all oncogenic Ras mutants block terminal differentiation of transit amplifying cells. By contrast, RASopathy associated K-Ras variants were less able to block differentiation. Profiling of eight targeted Ras-pathway drugs on seven oncogenic Ras mutants revealed their allele-specific activities and distinct abilities to restore normal differentiation as compared to triggering cell death. In particular, the MEK-inhibitor trametinib could broadly restore differentiation, while the mTOR-inhibitor rapamycin broadly suppressed differentiation. We expect that this quantitative assessment of the impact of Ras-pathway mutants and drugs on cellular differentiation has great potential to complement cancer cell proliferation data.
Topics: Cell Differentiation; Mutation; Animals; Mice; Protein Isoforms; ras Proteins; Cell Line; Humans
PubMed: 38795504
DOI: 10.1016/j.ejcb.2024.151425 -
Biomolecules May 2024Chimerism-based strategies represent a pioneering concept which has led to groundbreaking advancements in regenerative medicine and transplantation. This new approach... (Review)
Review
Chimerism-based strategies represent a pioneering concept which has led to groundbreaking advancements in regenerative medicine and transplantation. This new approach offers therapeutic potential for the treatment of various diseases, including inherited disorders. The ongoing studies on chimeric cells prompted the development of Dystrophin-Expressing Chimeric (DEC) cells which were introduced as a potential therapy for Duchenne Muscular Dystrophy (DMD). DMD is a genetic condition that leads to premature death in adolescent boys and remains incurable with current methods. DEC therapy, created via the fusion of human myoblasts derived from normal and DMD-affected donors, has proven to be safe and efficacious when tested in experimental models of DMD after systemic-intraosseous administration. These studies confirmed increased dystrophin expression, which correlated with functional and morphological improvements in DMD-affected muscles, including cardiac, respiratory, and skeletal muscles. Furthermore, the application of DEC therapy in a clinical study confirmed its long-term safety and efficacy in DMD patients. This review summarizes the development of chimeric cell technology tested in preclinical models and clinical studies, highlighting the potential of DEC therapy in muscle regeneration and repair, and introduces chimeric cell-based therapies as a promising, novel approach for muscle regeneration and the treatment of DMD and other neuromuscular disorders.
Topics: Muscular Dystrophy, Duchenne; Humans; Regeneration; Animals; Cell- and Tissue-Based Therapy; Muscle, Skeletal; Dystrophin; Myoblasts
PubMed: 38785982
DOI: 10.3390/biom14050575 -
Molecular Medicine Reports Jul 2024Promotion of myoblast differentiation by activating mitochondrial biogenesis and protein synthesis signaling pathways provides a potential alternative strategy to...
Promotion of myoblast differentiation by activating mitochondrial biogenesis and protein synthesis signaling pathways provides a potential alternative strategy to balance energy and overcome muscle loss and muscle disorders. (Lour.) Baill. extract (SCE) has been used extensively as a traditional herbal medicine and has several physiological activities, including anti‑asthmatic, anti‑oxidant, anti‑inflammatory, anti‑atopic, anticancer and hepatoprotective properties. However, the effects and mechanisms of action of SCE on muscle differentiation have not yet been clarified. In the present study, it was investigated whether SCE affects skeletal muscle cell differentiation through the regulation of mitochondrial biogenesis and protein synthesis in murine C2C12 myoblasts. The XTT colorimetric assay was used to determine cell viability, and myosin heavy chain (MyHC) levels were determined using immunocytochemistry. SCE was applied to C2C12 myotube at different concentrations (1, 5, or 10 ng/ml) and times (1,3, or 5 days). Reverse transcription‑quantitative PCR and western blotting were used to analyze the mRNA and protein expression change of factors related to differentiation, mitochondrial biogenesis and protein synthesis. Treatment of C2C12 cells with SCE at 1,5, and 10 ng/ml did not affect cell viability. SCE promoted C2C12 myotube formation and significantly increased MyHC expression in a concentration‑ and time‑dependent manner. SCE significantly increased the mRNA and protein expression of muscle differentiation‑specific markers, such as MyHC, myogenic differentiation 1, myogenin, Myogenic Factor 5, and β‑catenin, mitochondrial biosynthesis‑related factors, such as peroxisome proliferator‑activated receptor‑gamma coactivator‑1α, nuclear respirator factor‑1, AMP‑activated protein kinase phosphorylation, and histone deacetylase 5 and AKT/mTOR signaling factors related to protein synthesis. SCE may prevent skeletal muscle dysfunction by enhancing myoblast differentiation through the promotion of mitochondrial biogenesis and protein synthesis.
Topics: Animals; Mice; Cell Differentiation; Signal Transduction; TOR Serine-Threonine Kinases; Proto-Oncogene Proteins c-akt; Plant Extracts; Organelle Biogenesis; Cell Line; Saururaceae; Cell Survival; Myoblasts; Mitochondria; Muscle Development; Muscle Fibers, Skeletal; Myosin Heavy Chains; Muscle, Skeletal
PubMed: 38785149
DOI: 10.3892/mmr.2024.13250 -
Journal of Agricultural and Food... Jun 2024As cellular transcription factors and DNA replicators, nuclear factor I (NFI) family members play an important role in mammalian development. However, there is still a...
As cellular transcription factors and DNA replicators, nuclear factor I (NFI) family members play an important role in mammalian development. However, there is still a lack of research on the muscle regeneration of NFI family members in cattle. In this study, the analysis of family factors was conducted on their characterization, phylogenetics, and functional domains. We found that NFI family members were relatively conserved among different species, but there was heterogeneity in amino acid sequences, DNA coding sequences, and functional domain among members. Furthermore, among family factors, we observed that NFIC exhibited highly expression in bovine muscle tissues, particularly influencing the expression of proliferation marker genes in myoblasts. To investigate the influence of on myoblast proliferation, we knocked down (si-) and found that the proliferation of myoblasts was significantly promoted. In terms of regulation mechanism, we identified that si- could counteract the inhibitory effect of the cell cycle inhibitor RO-3306. Interestingly, CENPF, as the downstream target gene of NFIC, could affect the expression of CDK1, CCNB1, and actively regulate the cell cycle pathway and cell proliferation. In addition, when CENPF was knocked down, the phosphorylation of p53 and the expression of Bax were increased, but the expression of Bcl2 was inhibited. Our findings mainly highlight the mechanism by which NFIC acts on the CENPF/CDK1 axis to regulate the proliferation of bovine myoblasts.
Topics: Animals; Cattle; Cell Proliferation; Myoblasts; CDC2 Protein Kinase; NFI Transcription Factors; Gene Knockdown Techniques; Cell Cycle
PubMed: 38780097
DOI: 10.1021/acs.jafc.4c01811 -
Genome Research Jun 2024Facioscapulohumeral muscular dystrophy (FSHD) is linked to abnormal derepression of the transcription activator DUX4. This effect is localized to a low percentage of...
Single-cell spatial transcriptomics reveals a dystrophic trajectory following a developmental bifurcation of myoblast cell fates in facioscapulohumeral muscular dystrophy.
Facioscapulohumeral muscular dystrophy (FSHD) is linked to abnormal derepression of the transcription activator DUX4. This effect is localized to a low percentage of cells, requiring single-cell analysis. However, single-cell/nucleus RNA-seq cannot fully capture the transcriptome of multinucleated large myotubes. To circumvent these issues, we use multiplexed error-robust fluorescent in situ hybridization (MERFISH) spatial transcriptomics that allows profiling of RNA transcripts at a subcellular resolution. We simultaneously examined spatial distributions of 140 genes, including 24 direct DUX4 targets, in in vitro differentiated myotubes and unfused mononuclear cells (MNCs) of control, isogenic D4Z4 contraction mutant and FSHD patient samples, as well as the individual nuclei within them. We find myocyte nuclei segregate into two clusters defined by the expression of DUX4 target genes, which is exclusively found in patient/mutant nuclei, whereas MNCs cluster based on developmental states. Patient/mutant myotubes are found in "FSHD-hi" and "FSHD-lo" states with the former signified by high DUX4 target expression and decreased muscle gene expression. Pseudotime analyses reveal a clear bifurcation of myoblast differentiation into control and FSHD-hi myotube branches, with variable numbers of DUX4 target-expressing nuclei found in multinucleated FSHD-hi myotubes. Gene coexpression modules related to extracellular matrix and stress gene ontologies are significantly altered in patient/mutant myotubes compared with the control. We also identify distinct subpathways within the DUX4 gene network that may differentially contribute to the disease transcriptomic phenotype. Taken together, our MERFISH-based study provides effective gene network profiling of multinucleated cells and identifies FSHD-induced transcriptomic alterations during myoblast differentiation.
Topics: Muscular Dystrophy, Facioscapulohumeral; Humans; Myoblasts; Single-Cell Analysis; Muscle Fibers, Skeletal; Transcriptome; Homeodomain Proteins; Cell Differentiation; In Situ Hybridization, Fluorescence; Gene Expression Profiling
PubMed: 38777608
DOI: 10.1101/gr.278717.123 -
Comparative Biochemistry and... Sep 2024Previous research has shown that leucine (Leu) can stimulate and enhance the proliferation of equine skeletal muscle satellite cells (SCs). The gene expression profile...
Previous research has shown that leucine (Leu) can stimulate and enhance the proliferation of equine skeletal muscle satellite cells (SCs). The gene expression profile associated with Leu-induced proliferation of equine SCs has also been documented. However, the specific role of Leu in regulating the expression of slow-twitch muscle fibers (slow-MyHC) and mitochondrial function in equine SCs, as well as the underlying mechanism, remains unclear. During this investigation, equine SCs underwent culturing in differentiation medium and were subjected to varying concentrations of Leu (0 mM, 0.5 mM, 1 mM, 2 mM, 5 mM, and 10 mM) over a span of 3 days. AMP-activated protein kinase (AMPK) inhibitor Compound C and mammalian target of rapamycin complex (mTOR) inhibitor Rapamycin were utilized to explore its underlying mechanism. Here we showed that the expression of slow-MyHC at 2 mM Leu level was significantly higher than the concentration levels of 0 mM,0.5 mM and 10 mM (P <0.01), and there was no significant difference compared to other groups (P > 0.05); the basal respiration, maximum respiration, standby respiration and the expression of slow-MyHC, PGC-1α, Cytc, ND1, TFAM, and COX1 were significantly increased with Leu supplementation (P < 0.01). We also found that Leu up-regulated the expression of key proteins on AMPK and mTOR signaling pathways, including LKB1, p-LKB1, AMPK, p-AMPK, S6, p-S6, 4EBP1, p-4EBP1, mTOR and p-mTOR (P < 0.05 or P < 0.01). Notably, when we treated the equine SCs with the AMPK inhibitor Compound C and the mTOR inhibitor Rapamycin, we observed a reduction in the beneficial effects of Leu on the expression of genes related to slow-MyHC and signaling pathway-related gene expressions. This study provides novel evidence that Leu promotes slow-MyHC expression and enhances mitochondrial function in equine SCs through the AMPK/mTOR signaling pathways, shedding light on the underlying mechanisms involved in these processes for the first time.
Topics: Animals; Leucine; TOR Serine-Threonine Kinases; Satellite Cells, Skeletal Muscle; Signal Transduction; Horses; AMP-Activated Protein Kinases; Energy Metabolism; Muscle Fibers, Slow-Twitch; Cells, Cultured
PubMed: 38776751
DOI: 10.1016/j.cbd.2024.101249 -
Animal Biotechnology Nov 2024Tropomyosin 3 () plays a significant role as a regulatory protein in muscle contraction, affecting the growth and development of skeletal muscles. Despite its...
Tropomyosin 3 () plays a significant role as a regulatory protein in muscle contraction, affecting the growth and development of skeletal muscles. Despite its importance, limited research has been conducted to investigate the influence of on bovine skeletal muscle development. Therefore, this study revealed the role of in bovine myoblast growth and development. This research involved conducting a thorough examination of the Qinchuan cattle gene using bioinformatics tools to examine its sequence and structural characteristics. Furthermore, expression was evaluated in various bovine tissues and cells using quantitative real-time polymerase chain reaction (qRT-PCR). The results showed that the coding region of spans 855 bp, with the 161st base being the T base, encoding a protein with 284 amino acids and 19 phosphorylation sites. This protein demonstrated high conservation across species while displaying a predominant α-helix secondary structure despite being an unstable acidic protein. Notably, a noticeable increase in expression was observed in the longissimus dorsi muscle and myocardium of calves and adult cattle. Expression patterns varied during different stages of myoblast differentiation. Functional studies that involved interference with in Qinchuan cattle myoblasts revealed a very significantly decrease in S-phase cell numbers and EdU-positive staining ( < 0.01), and disrupted myotube morphology. Moreover, interference with resulted in significantly ( < 0.05) or highly significantly ( < 0.01) decreased mRNA and protein levels of key proliferation and differentiation markers, indicating its role in the modulation of myoblast behavior. These findings suggest that plays an essential role in bovine skeletal muscle growth by influencing myoblast proliferation and differentiation. This study provides a foundation for further exploration into the mechanisms underlying -mediated regulation of bovine muscle development and provides valuable insights that could guide future research directions as well as potential applications for livestock breeding and addressing muscle-related disorders.
Topics: Animals; Cattle; Tropomyosin; Cell Proliferation; Cell Differentiation; Myoblasts; Cloning, Molecular; Muscle, Skeletal; Amino Acid Sequence; Muscle Development
PubMed: 38775564
DOI: 10.1080/10495398.2024.2345238 -
Scientific Reports May 2024Barth syndrome (BTHS) is a rare disorder caused by mutations in the TAFAZZIN gene. Previous studies from both patients and model systems have established metabolic...
Barth syndrome (BTHS) is a rare disorder caused by mutations in the TAFAZZIN gene. Previous studies from both patients and model systems have established metabolic dysregulation as a core component of BTHS pathology. In particular, features such as lactic acidosis, pyruvate dehydrogenase (PDH) deficiency, and aberrant fatty acid and glucose oxidation have been identified. However, the lack of a mechanistic understanding of what causes these conditions in the context of BTHS remains a significant knowledge gap, and this has hindered the development of effective therapeutic strategies for treating the associated metabolic problems. In the current study, we utilized tafazzin-knockout C2C12 mouse myoblasts (TAZ-KO) and cardiac and skeletal muscle tissue from tafazzin-knockout mice to identify an upstream mechanism underlying impaired PDH activity in BTHS. This mechanism centers around robust upregulation of pyruvate dehydrogenase kinase 4 (PDK4), resulting from hyperactivation of AMP-activated protein kinase (AMPK) and subsequent transcriptional upregulation by forkhead box protein O1 (FOXO1). Upregulation of PDK4 in tafazzin-deficient cells causes direct phospho-inhibition of PDH activity accompanied by increased glucose uptake and elevated intracellular glucose concentration. Collectively, our findings provide a novel mechanistic framework whereby impaired tafazzin function ultimately results in robust PDK4 upregulation, leading to impaired PDH activity and likely linked to dysregulated metabolic substrate utilization. This mechanism may underlie previously reported findings of BTHS-associated metabolic dysregulation.
Topics: Animals; Mice; Forkhead Box Protein O1; AMP-Activated Protein Kinases; Mice, Knockout; Pyruvate Dehydrogenase Acetyl-Transferring Kinase; Transcription Factors; Up-Regulation; Signal Transduction; Myoblasts; Cell Line; Glucose; Acyltransferases
PubMed: 38769106
DOI: 10.1038/s41598-024-62262-1 -
Journal of Animal Science Jan 2024Skeletal muscle is an important component of livestock and poultry organisms. The proliferation and differentiation of myoblasts are highly coordinated processes, which...
Skeletal muscle is an important component of livestock and poultry organisms. The proliferation and differentiation of myoblasts are highly coordinated processes, which rely on the regulation of miRNA. MiRNAs are widely present in organisms and play roles in various biological processes, including cell proliferation, differentiation, and apoptosis. MiR-181d and miR-196a, identified as tumor suppressors, have been found to be involved in cell proliferation, apoptosis, directed differentiation, and cancer cell invasion. However, their role in beef cattle skeletal muscle metabolism remains unclear. In this study, we discovered that overexpression of bta-miR-181d and bta-miR-196a in Qinchuan cattle myoblasts inhibited proliferation and apoptosis while promoting myogenic differentiation through EDU staining, flow cytometry analysis, immunofluorescence staining, and Western blotting. RNA-seq analysis of differential gene expression revealed that after overexpression of bta-miR-181d and bta-miR-196a, the differentially expressed genes were mainly enriched in the PI3K-Akt and MAPK signaling pathways. Furthermore, the phosphorylation levels of key proteins p-AKT in the PI3K signaling pathway and p-MAPK in the MAPK signaling pathway were significantly decreased after overexpression of bta-miR-181d and bta-miR-196a. Overall, this study provides preliminary evidence that bta-miR-181d and bta-miR-196a may regulate proliferation, apoptosis, and differentiation processes in Qinchuan cattle myoblasts by affecting the phosphorylation status of key proteins in PI3K-Akt and MAPK-ERK signaling pathways.
Topics: Animals; Cattle; MicroRNAs; Apoptosis; Cell Proliferation; Cell Differentiation; Myoblasts; Muscle Development; Signal Transduction; Phosphatidylinositol 3-Kinases
PubMed: 38766769
DOI: 10.1093/jas/skae142