Satellite Cells Research Articles

Cyr61 Promotes D-gal-induced Aging C2C12 Cell Fibrosis by Modulating Wnt/β-catenin Signaling Pathways.

Cyr61 Promotes D-gal-induced Aging C2C12 Cell Fibrosis by Modulating Wnt/β-catenin Signaling Pathways.

The influence of age on cellular senescence in injured versus healthy muscle and its implications on rotator cuff injuries.

The influence of age on cellular senescence in injured versus healthy muscle and its implications on rotator cuff injuries.

Establishment and characterization of immortalized Tibetan pig skeletal muscle satellite cells for cultured meat applications

Establishment and characterization of immortalized Tibetan pig skeletal muscle satellite cells for cultured meat applications

Myogenic nano-adjuvant for orthopedic-related sarcopenia via mitochondrial homeostasis modulation in macrophage-myosatellite metabolic crosstalk

The decline in skeletal muscle mass and muscle strength linked to aging, also known as sarcopenia, is strongly associated with disability, traumatic injury, and metabolic disease in patients. Meanwhile, sarcopenia increases the risk of adverse orthopedic perioperative complications including implant dislocation, infection, loosening, and poor wound healing. Mitochondrial dyshomeostasis in the immune-myosatellite metabolic crosstalk is one of the major pathological factors in sarcopenia. To reduce the incidence of orthopedic perioperative complications in patients, we designed and developed a nano-adjuvant based on two-dimensional layer double hydroxide (LDH) for sustained improvement of systemic and orthopedic-related sarcopenia. Construction of MgAlCo-LDH@UA (MACL@UA) nano-adjuvant was performed by introducing cobalt in magnesium-aluminum LDH and further loading urolithin A (UA). The release of magnesium ions and UA promoted myocyte proliferation, angiogenesis and improved mitochondrial homeostasis. Al acted as an immunomodulatory adjuvant to enhance the metabolic crosstalk between macrophages and myosatellite cells, and prompted macrophage-derived glutamine nourishment. Animal experiments confirmed that vaccination with MACL@UA in systemic sarcopenia and intensive orthopedic perioperative vaccination with MACL@UA significantly enhanced quadriceps muscle mass in rats. This nano-adjuvant offers a solution for long-term improvement of sarcopenia and short-term significant reduction of orthopedic perioperative complications in patients, with promising prospects for clinical application and commercial translation.

Multi-Omics Identification of Fos as a Central Regulator in Skeletal Muscle Adaptation to Long-Term Aerobic Exercise

Skeletal muscle health and function are closely linked to long-term aerobic exercise, particularly in enhancing muscle metabolism and regulating gene expression. Regular endurance training can significantly ameliorate metabolic dysfunction and prevent chronic diseases. However, the precise molecular mechanisms underlying skeletal muscle adaptations to long-term aerobic exercise require further clarification. To address this, we integrated transcriptomic and single-cell omics datasets from multiple long-term aerobic exercise models retrieved from the GEO database. After merging and batch correction, differential expression analysis identified 204 DEGs, including 110 upregulated and 94 downregulated genes. Key feature genes were screened using Lasso regression, SVM-RFE, and Random Forest machine learning algorithms, validated by RT-qPCR, and refined through PPI network analysis. Among them, Fos and Tnfrsf12a were significantly downregulated following long-term aerobic exercise. Notably, Fos exhibited a more pronounced decrease than Tnfrsf12a, and was strongly associated with inflammation and muscle regeneration. PPI network analysis indicated that Fos interacted with genes such as Casp3, Egr1, Aft3, Hspa5, Src, and Igf2. GO, KEGG, and GSEA enrichment analyses revealed that Fos is involved in skeletal muscle differentiation, tissue remodeling, and the NF-κB inflammatory pathway. ssGSEA analysis further showed that samples with low Fos expression had significantly elevated Th1/Th2 and Treg cell infiltration. Single-cell analysis confirmed preferential Fos expression in muscle fiber/adipocyte progenitors, satellite cells, and tenocytes, all critical for myogenesis. In summary, our findings suggest that long-term aerobic exercise downregulates Fos, potentially alleviating inflammation and enhancing satellite cell-mediated muscle regeneration. Fos may serve as a central regulator of skeletal muscle remodeling during long-term aerobic exercise.

GsMTx4-blocked PIEZO1 channel promotes myogenic differentiation and alleviates myofiber damage in Duchenne muscular dystrophy

BackgroundDuchenne muscular dystrophy (DMD) is a debilitating disease characterized by progressive muscle-wasting and a lack of effective therapy. Although the application of GsMTx4 has been shown to reduce muscle mass loss in dystrophic mice, the mechanism of action remains unclear.MethodsWe employed single-nucleus RNA sequencing data to scrutinize the expression of mechanosensitive channels in skeletal muscle. The upregulation of PIEZO1 and its precise localization were corroborated in DMD patients, mdx mice, and activated satellite cells. To delve into the role of the GsMTx4-blocked PIEZO1 channel in the myogenic program, we conducted comprehensive in vitro and in vivo studies encompassing the proliferation of satellite cells, differentiation of myoblasts, and calcium influx into myofibers. Utilizing both a PIEZO1 channel inhibitor, GsMTx4, and a PIEZO1 channel agonist, Yoda1, we explored the PIEZO1 channel’s impact on satellite cell proliferation and myogenic differentiation. Additionally, we explored the protective effect of the PIEZO1 channel on myofiber calcium influx using mdx mouse models and isolated single myofibers.ResultsPIEZO1 was upregulated in the muscle of DMD patients and was predominantly expressed in satellite cells and upregulated during satellite cell proliferation. Treatment with GsMTx4 increased the cross-sectional areas of myofibers and reduced the proportion of centrally nucleated fibers in mdx mice. GsMTx4 inhibited satellite cell proliferation while promoting myogenic differentiation. During myogenic differentiation, the YAP nuclear-cytoplasmic ratio increased in cells treated with GsMTx4 and showed a significant correlation with the nuclear localization of MyoG. In myofibers, GsMTx4 significantly reduced the level of p-CaMKII/CaMKII in muscle and calcium load.ConclusionsPIEZO1 upregulation in DMD could potentially stem from an elevated proportion of proliferating satellite cells triggered by sarcolemma damage and muscle necrosis. The inhibition of the PIEZO1 channel by GsMTx4 plays a beneficial role in fostering myogenic differentiation and mitigating myofiber damage. The PIEZO1 channel emerges as a promising therapeutic target for addressing DMD.

Quantitative Proteomics Revealed the Molecular Regulatory Network of Lysine and the Effects of Lysine Supplementation on Sunit Skeletal Muscle Satellite Cells.

Stimulating skeletal muscle satellite cells (SMSCs) with amino acids improves their proliferation and differentiation, enhancing skeletal muscle mass, thereby increasing lean meat rate. This study explored lysine (Lys)'s effects on SMSCs and their protein profiles in Sunit sheep. SMSCs were successfully isolated, assessing their survival and proliferation after Lys stimulation at varying concentrations using the CCK-8 assay. Western blotting revealed Lys-induced changes in myogenic differentiation protein expression, while immunocytochemistry detected α-Actinin and Myostatin within the SMSCs. TMT proteomics identified differentially expressed proteins, which underwent functional and interaction analyses, with RT-qPCR validating the corresponding gene expression. This study revealed that 4 mmol/L of Lys significantly boosted SMSC proliferation. A 24 h stimulation with this concentration reduced Myostatin expression, and increased MYOD1 and α-Actinin levels in the SMSCs. A proteomic analysis identified 577 differentially expressed proteins, primarily associated with lipoblast differentiation and muscle development, as highlighted by the GO enrichment analysis. A pathway analysis further demonstrated these proteins' involvement in the autophagy-lysosome and NOD-like receptor signaling pathways. Lys enhances SMSC proliferation, differentiation, and adipogenesis in Sunit sheep, exhibiting antioxidant properties and supporting muscle stability and amino acid metabolism. It may also have anti-inflammatory, anti-pyroptotic, and proteolysis-inhibitory effects, offering insights into muscle growth mechanisms through amino acid supplementation in ruminants.

Insights into human muscle biology from human primary skeletal muscle cell culture.

This review arises from the symposium held in honour of Prof Jenny Morgan at UCL in 2024 and the authors would like to acknowledge the outstanding contribution that Prof Morgan has made to the field of translational muscle cell biology. Prof Morgan published a review article in 2010 entitled: Are human and mice satellite cells really the same? In which the authors highlighted differences between species which are still pertinent to skeletal muscle cell culture studies today. To our knowledge there are no comprehensive reviews which outline the considerable work that has been undertaken using human primary skeletal muscle origin cells as the main model system. This review highlights the multitude of muscle biology that has been investigated using human primary cells, as well as discussing the advantages and disadvantages over other cell models. We also discuss future directions for primary cell culture models utilising the latest technologies in cell type specificity and culture systems.

MiR-2400 promotes proliferation of bovine skeletal muscle-derived satellite cells by regulating MAGED1 genes expression.

microRNAs play a crucial role in the intricate process of muscle satellite cells proliferation and differentiation. Previous studies have demonstrated that miR-2400 can regulate bovine skeletal muscle satellite cell (MuSCs) proliferation, yet the underlying mechanism remains incompletely elucidated. In this study, we employed bioinformatics prediction and dual luciferase reporter assays to establish that miR-2400 directly targets the 3' untranslated regions (UTRs) of melanoma antigen family D1 (MAGED1) mRNA, thereby suppressing its expression. To ascertain whether miR-2400 affects the proliferation of MuSCs through MAGED1, we constructed the MAGED1 interference vector using RNA interference technology (RNAi) and assessed changes in MuSCs proliferation subsequent to MAGED1 interference. The experimental data indicate that the cell viability and the rate of EdU-positive cells of MuSCs were increased after interference with MAGED1. The proportion of S-phase cells and the expression level of cell cycle-associated proteins CCND2 and CCNB1 increased. These findings align with miR-2400's role in promoting cell proliferation and suggest that miR-2400 exerts its effects by directly targeting MAGED1.

Metabolomic insights of cultured meat compared to conventional meat

The growing global demand for sustainable food sources has accelerated the development of cultured meat as an alternative to traditional animal-based meat. Cultured meat is produced through advanced cell cultivation techniques, offering potential solutions to environmental, ethical, and food security challenges. This study aims to predict the safety of cultured meat compared to conventional chicken using a comprehensive metabolomics approach. We conducted a comparative analysis of conventional chicken meat, muscle satellite cells, and myotube formed cells. The findings reveal that while the overall metabolic profiles of cultured and conventional meats are largely comparable, significant differences exist in specific metabolites associated with nutrient metabolism. These variations suggest potential differences in the nutritional content of cultured meat, which could affect its dietary value. Despite these differences, our analysis indicates no significant impact on the safety of cultured meat, which remains within acceptable safety limits. This study contributes to the ongoing evaluation of cultured meat as a viable and safe alternative in the pursuit of sustainable food sources.

Histopathological analysis of respiratory muscles in patients with acute COVID-19 infection.

Coronavirus-disease 2019 (COVID-19) affects the respiratory system with high morbidity in elderly and comorbid patients. Acute COVID-19 infection (CI) primarily leads to respiratory failure, long-term effects on respiratory skeletal muscle however remain vague. Thus, histopathological marker expression of oxidative stress, inflammation, satellite cell activity, myosin fiber composition, and cellular senescence were analyzed in intercostal muscle and diaphragm to compare respiratory muscle degeneration (RMD) in deceased CI-positive and control patients. Beside CI, the impact of BMI, age, sex, ventilation status, and duration of hospitalization on RMD were evaluated. CI-positive patients exhibited higher numbers of regenerative stem cells, but no association between CI status and RMD was observed. Interestingly, ventilation support and lung-associated comorbidities had no effect on expression of RMD markers (p > 0.05). However, intercostal muscle showed BMI-dependent changes in expression of RMD markers, regardless of the CI status, with increased cytokine expression (p = 0.04), reduced antioxidative capacity (p = 0.05), and low stem cell prevalence (p = 0.02) in patients with high BMI. Moreover, elderly patients demonstrated increased oxidative stress (p = 0.001) and cell senescence (p = 0.03) independent of CI status. Notably, immobility drives muscle fiber transformation to Myosin ST (p = 0.03), since prolonged hospitalization correlated with muscle fiber type shift. Limitations included incomplete retrospective data collection and absence of adequate samples for molecular analyses. Together, RMD is influenced by BMI, age and immobility rather than the CI status alone. Future studies including larger cohorts, molecular analyses, and evaluation of patient data in addition to CI status alone, will further support meaningful analyses and interpretation of RMD and its impact on post CI recovery.

Engineering the immune and fibrotic response in VML.

Volumetric muscle loss (VML) provides a significant challenge for regeneration, despite current treatments with free functional muscle transfer. VML injury overwhelms the native process of wound healing, leading to a dysregulated immune response and eventually fibrosis. Tissue engineered muscle grafts are a promising method of treatment without donor site morbidity. Tissue engineered muscle grafts not only provide structural support, but also address the myogenic deficit by transplanting satellite cells and myoblasts to supplement those lost as a result of injury and secrete additional stimuli to create a more pro-regenerative microenvironment. However, adequate treatment of VML also requires immune modulation and limiting fibrotic deposition. To address this, some approaches have targeted other cells involved in the injury response such as macrophages, regulatory T cells, fibroadipogenic progenitor, and myofibroblasts. Treatments that supplement myogenic cells at the same time as co-delivering either immune or fibrotic modulatory signals have demonstrated increased success. One limitation is that many of these treatments are being tested in models that exhibit limited fibrosis, and the observed benefits of treatment may not be seen in more clinically relevant scenarios. Future studies may also address the incomplete understanding of the cellular signalling responses that ameliorate fibrosis. We provide a summation of recent strategies employed for this purpose, as well as predictions about new strategies yet to be utilized in VML.

Neuromuscular electrical stimulation alleviates stroke-related sarcopenia by promoting satellite cells myogenic differentiation via AMPK-ULK1-Autophagy axis.

Neuromuscular electrical stimulation alleviates stroke-related sarcopenia by promoting satellite cells myogenic differentiation via AMPK-ULK1-Autophagy axis.

Physical training reduces cell senescence and associated insulin resistance in skeletal muscle.

Physical training reduces cell senescence and associated insulin resistance in skeletal muscle.

Resistance exercise and mechanical overload upregulate vimentin for skeletal muscle remodeling.

We adopted a proteomic and follow-through approach to investigate how mechanical overload (MOV) potentially affects novel targets in skeletal muscle, and how a perturbation in this response could potentially affect the adaptive response. First, we determined that 10 wk of resistance training in 15 college-aged females increased sarcolemmal-associated protein content (+10.1%, P < 0.05). Sarcolemmal protein isolates were then queried using mass spectrometry-based proteomics, ∼10% (38/387) of proteins putatively associated with the sarcolemma or extracellular matrix (ECM) were upregulated (>1.5-fold, P < 0.05), and one target (intermediate filament vimentin; VIM) warranted further investigation due to its correlation to myofiber hypertrophy (r = 0.652, P = 0.009). VIM expression was then examined in 4-mo-old C57BL/6J mice following 10 and 20 days of plantaris MOV via synergist ablation. Relative to Sham (control) mice, VIM mRNA and protein content was significantly higher in MOV mice, and immunohistochemistry indicated that VIM predominantly resided in the ECM. MOV experiments were replicated in Pax7-DTA (satellite cell depleted) mice, which reduced VIM in the ECM by ∼74%. A third MOV experiment was performed in C57BL/6 mice intramuscularly injected with either AAV9-scrambled (control) or AAV9-VIM-shRNA. Although VIM-shRNA mice possessed lower VIM in the ECM (∼45%), plantaris masses in response to MOV were similar between groups. However, VIM-shRNA mice possessed smaller and more centrally nucleated MyHCemb-positive fibers in response to MOV. In summary, skeletal muscle VIM appears to be enriched in the ECM following MOV, satellite cells may regulate its expression, and a disruption in expression during MOV leads to an excessive regenerative phenotype.NEW & NOTEWORTHY Our highly integrative approach suggests that skeletal muscle vimentin seems to function as a mechanosensitive protein that becomes enriched in the extracellular matrix following MOV. Satellite cells may play a role in regulating their expression, and an exaggerated regenerative response occurs when vimentin expression becomes dysregulated during mechanical overload. Although these data implicate vimentin in aiding with tissue remodeling following MOV, more data are needed to determine the functional ramifications of VIM response deficiencies.

P2Y12 signaling in muscle satellite cells contributes to masseter muscle contraction-induced pain.

P2Y12 signaling in muscle satellite cells contributes to masseter muscle contraction-induced pain.

Low-cost food-grade alternatives for serum albumins in FBS-free cell culture media

Cultivated meat may be an ethical, environmentally friendly, antibiotic-free meat alternative of the future. As of now, one of the main limiting factors for bringing cultivated meat to the market is the high cost of the cell culture media and their great dependency on serum albumins, production of which is predicted to become a major bottleneck of this industry. Here, using bovine muscle stem cells, we optimized serum free B8/B9 medium. We identified several food grade, low-price medium stabilizers, exhibiting comparable or even superior stabilization of the B8 medium in short- and long-term cultivations, as compared to recombinant human serum albumin. We show transferability of our approach to other satellite cells (porcine, chicken) and CHO cells, though significant cell-line specific differences in response to stabilizers were observed. Thus, we provide an alternative to serum albumin, enabling up to an overall 73% reduction of medium price for certain cell lines.

Dysfunctional terminal differentiation of satellite cells in the wooden breast muscle of Ross 308 broiler chickens.

Dysfunctional terminal differentiation of satellite cells in the wooden breast muscle of Ross 308 broiler chickens.

Effects of circPICALM-miR-132-PHKB regulated by METTL3 on proliferation of porcine skeletal muscle satellite cells.

Effects of circPICALM-miR-132-PHKB regulated by METTL3 on proliferation of porcine skeletal muscle satellite cells.

Exploring the influence of polystyrene-nanoplastics on two distinct in vitro systems in farm animals: A pilot study.

Exploring the influence of polystyrene-nanoplastics on two distinct in vitro systems in farm animals: A pilot study.