scholarly journals Fibro-adipogenic progenitors in skeletal muscle homeostasis, regeneration and diseases

Open Biology ◽  
2021 ◽  
Vol 11 (12) ◽  
Author(s):  
Thomas Molina ◽  
Paul Fabre ◽  
Nicolas A. Dumont
Keyword(s):  
Skeletal Muscle ◽  
Stem Cells ◽  
Muscle Regeneration ◽  
New Technologies ◽  
Cell Activity ◽  
Cellular Heterogeneity ◽  
Skeletal Muscle Regeneration ◽  
Acute Injury ◽  
Muscle Stem Cells ◽  
Muscle Homeostasis

Skeletal muscle possesses a remarkable regenerative capacity that relies on the activity of muscle stem cells, also known as satellite cells. The presence of non-myogenic cells also plays a key role in the coordination of skeletal muscle regeneration. Particularly, fibro-adipogenic progenitors (FAPs) emerged as master regulators of muscle stem cell function and skeletal muscle regeneration. This population of muscle resident mesenchymal stromal cells has been initially characterized based on its bi-potent ability to differentiate into fibroblasts or adipocytes. New technologies such as single-cell RNAseq revealed the cellular heterogeneity of FAPs and their complex regulatory network during muscle regeneration. In acute injury, FAPs rapidly enter the cell cycle and secrete trophic factors that support the myogenic activity of muscle stem cells. Conversely, deregulation of FAP cell activity is associated with the accumulation of fibrofatty tissue in pathological conditions such as muscular dystrophies and ageing. Considering their central role in skeletal muscle pathophysiology, the regulatory mechanisms of FAPs and their cellular and molecular crosstalk with muscle stem cells are highly investigated in the field. In this review, we summarize the current knowledge on FAP cell characteristics, heterogeneity and the cellular crosstalk during skeletal muscle homeostasis and regeneration. We further describe their role in muscular disorders, as well as different therapeutic strategies targeting these cells to restore muscle regeneration.

scholarly journals R-spondin1 regulates muscle progenitor cell fusion through control of antagonist Wnt signaling pathways

2016 ◽  
Author(s):  
Floriane Lacour ◽  
Elsa Vezin ◽  
Florian Bentzinger ◽  
Marie-Claude Sincennes ◽  
Robert D. Mitchell ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Stem Cells ◽  
Stem Cell ◽  
Wnt Signaling ◽  
Signaling Pathways ◽  
Muscle Regeneration ◽  
Muscle Cells ◽  
Skeletal Muscle Regeneration ◽  
Acute Injury ◽  
Canonical Wnt

SUMMARYTissue regeneration requires the selective activation and repression of specific signaling pathways in stem cells. As such, the Wnt signaling pathways have been shown to control stem cell fate. In many cell types, the R-Spondin (Rspo) family of secreted proteins acts as potent activators of the canonical Wnt/β-catenin pathway. Here, we identify Rspo1 as a mediator of skeletal muscle tissue repair. Firstly we show that Rspo1-null muscles do not display any abnormalities at the basal level. However deletion of Rspo1 results in global alteration of muscle regeneration kinetics following acute injury. We found that muscle stem cells lacking Rspo1 show delayed differentiation. Transcriptome analysis further demonstrated that Rspo1 is required for the activation of Wnt/β-catenin target genes in muscle cells. Furthermore, muscle cells lacking Rspo1 fuse with a higher frequency than normal cells, leading to larger myotubes containing more nuclei both in vitro and in vivo. We found the increase in muscle fusion was dependent on up-regulation of non-canonical Wnt7a/Fzd7/Rac1 signaling. We conclude that antagonistic control of canonical and non-canonical Wnt signaling pathways by Rspo1 in muscle stem cell progeny is important for restitution of normal muscle architecture during skeletal muscle regeneration.

scholarly journals PPARγ Controls Ectopic Adipogenesis and Cross-Talks with Myogenesis During Skeletal Muscle Regeneration

2018 ◽  
Vol 19 (7) ◽  
pp. 2044 ◽  
Author(s):  
Gabriele Dammone ◽  
Sonia Karaz ◽  
Laura Lukjanenko ◽  
Carine Winkler ◽  
Federico Sizzano ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Stem Cells ◽  
Adipose Tissue ◽  
Muscle Regeneration ◽  
Ex Vivo ◽  
Skeletal Muscle Regeneration ◽  
Whole Body ◽  
Muscle Repair ◽  
Muscle Stem Cells ◽  
Muscle Fat Infiltration

Skeletal muscle is a regenerative tissue which can repair damaged myofibers through the activation of tissue-resident muscle stem cells (MuSCs). Many muscle diseases with impaired regeneration cause excessive adipose tissue accumulation in muscle, alter the myogenic fate of MuSCs, and deregulate the cross-talk between MuSCs and fibro/adipogenic progenitors (FAPs), a bi-potent cell population which supports myogenesis and controls intra-muscular fibrosis and adipocyte formation. In order to better characterize the interaction between adipogenesis and myogenesis, we studied muscle regeneration and MuSC function in whole body Pparg null mice generated by epiblast-specific Cre/lox deletion (PpargΔ/Δ). We demonstrate that deletion of PPARγ completely abolishes ectopic muscle adipogenesis during regeneration and impairs MuSC expansion and myogenesis after injury. Ex vivo assays revealed that perturbed myogenesis in PpargΔ/Δ mice does not primarily result from intrinsic defects of MuSCs or from perturbed myogenic support from FAPs. The immune transition from a pro- to anti-inflammatory MuSC niche during regeneration is perturbed in PpargΔ/Δ mice and suggests that PPARγ signaling in macrophages can interact with ectopic adipogenesis and influence muscle regeneration. Altogether, our study demonstrates that a PPARγ-dependent adipogenic response regulates muscle fat infiltration during regeneration and that PPARγ is required for MuSC function and efficient muscle repair.

scholarly journals Progressive and Coordinated Mobilization of the Skeletal Muscle Niche throughout Tissue Repair Revealed by Single-Cell Proteomic Analysis

Cells ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 744
Author(s):  
Matthew Borok ◽  
Nathalie Didier ◽  
Francesca Gattazzo ◽  
Teoman Ozturk ◽  
Aurelien Corneau ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Stem Cells ◽  
Stem Cell ◽  
Muscle Regeneration ◽  
Cell Types ◽  
Skeletal Muscle Regeneration ◽  
Muscle Repair ◽  
Muscle Stem Cell ◽  
Muscle Stem Cells ◽  
Cell Lineages

Background: Skeletal muscle is one of the only mammalian tissues capable of rapid and efficient regeneration after trauma or in pathological conditions. Skeletal muscle regeneration is driven by the muscle satellite cells, the stem cell population in interaction with their niche. Upon injury, muscle fibers undergo necrosis and muscle stem cells activate, proliferate and fuse to form new myofibers. In addition to myogenic cell populations, interaction with other cell types such as inflammatory cells, mesenchymal (fibroadipogenic progenitors—FAPs, pericytes) and vascular (endothelial) lineages are important for efficient muscle repair. While the role of the distinct populations involved in skeletal muscle regeneration is well characterized, the quantitative changes in the muscle stem cell and niche during the regeneration process remain poorly characterized. Methods: We have used mass cytometry to follow the main muscle cell types (muscle stem cells, vascular, mesenchymal and immune cell lineages) during early activation and over the course of muscle regeneration at D0, D2, D5 and D7 compared with uninjured muscles. Results: Early activation induces a number of rapid changes in the proteome of multiple cell types. Following the induction of damage, we observe a drastic loss of myogenic, vascular and mesenchymal cell lineages while immune cells invade the damaged tissue to clear debris and promote muscle repair. Immune cells constitute up to 80% of the mononuclear cells 5 days post-injury. We show that muscle stem cells are quickly activated in order to form new myofibers and reconstitute the quiescent muscle stem cell pool. In addition, our study provides a quantitative analysis of the various myogenic populations during muscle repair. Conclusions: We have developed a mass cytometry panel to investigate the dynamic nature of muscle regeneration at a single-cell level. Using our panel, we have identified early changes in the proteome of stressed satellite and niche cells. We have also quantified changes in the major cell types of skeletal muscle during regeneration and analyzed myogenic transcription factor expression in satellite cells throughout this process. Our results highlight the progressive dynamic shifts in cell populations and the distinct states of muscle stem cells adopted during skeletal muscle regeneration. Our findings give a deeper understanding of the cellular and molecular aspects of muscle regeneration.

scholarly journals Zfp423 Regulates Skeletal Muscle Regeneration and Proliferation

2019 ◽  
Vol 39 (8) ◽  
Author(s):  
William N. Addison ◽  
Katherine C. Hall ◽  
Shoichiro Kokabu ◽  
Takuma Matsubara ◽  
Martin M. Fu ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Stem Cells ◽  
Muscle Regeneration ◽  
Affinity Purification ◽  
Skeletal Muscle Regeneration ◽  
Myoblast Differentiation ◽  
Muscle Stem Cells ◽  
Neuronal Precursors ◽  
A Cell ◽  
Skeletal Muscle Stem Cells

ABSTRACT Satellite cells (SCs) are skeletal muscle stem cells that proliferate in response to injury and provide myogenic precursors for growth and repair. Zfp423 is a transcriptional cofactor expressed in multiple immature cell populations, such as neuronal precursors, mesenchymal stem cells, and preadipocytes, where it regulates lineage allocation, proliferation, and differentiation. Here, we show that Zfp423 regulates myogenic progression during muscle regeneration. Zfp423 is undetectable in quiescent SCs but becomes expressed during SC activation. After expansion, Zfp423 is gradually downregulated as committed SCs terminally differentiate. Mice with satellite-cell-specific Zfp423 deletion exhibit severely impaired muscle regeneration following injury, with aberrant SC expansion, defective cell cycle exit, and failure to transition efficiently from the proliferative stage toward commitment. Consistent with a cell-autonomous role of Zfp423, shRNA-mediated knockdown of Zfp423 in myoblasts inhibits differentiation. Surprisingly, forced expression of Zfp423 in myoblasts induces differentiation into adipocytes and arrests myogenesis. Affinity purification of Zfp423 in myoblasts identified Satb2 as a nuclear partner of Zfp423 that cooperatively enhances Zfp423 transcriptional activity, which in turn affects myoblast differentiation. In conclusion, by controlling SC expansion and proliferation, Zfp423 is essential for muscle regeneration. Tight regulation of Zfp423 expression is essential for normal progression of muscle progenitors from proliferation to differentiation.

scholarly journals The role of Pitx2 and Pitx3 in muscle stem cells gives new insights into P38α MAP kinase and redox regulation of muscle regeneration

eLife ◽  
2018 ◽  
Vol 7 ◽  
Author(s):  
Aurore L'honoré ◽  
Pierre-Henri Commère ◽  
Elisa Negroni ◽  
Giorgia Pallafacchina ◽  
Bertrand Friguet ◽  
...  
Keyword(s):  
Stem Cells ◽  
Map Kinase ◽  
Satellite Cells ◽  
Muscle Regeneration ◽  
Redox Regulation ◽  
Primary Cultures ◽  
Rapid Expansion ◽  
Skeletal Muscle Regeneration ◽  
Muscle Stem Cells ◽  
P38α Map Kinase

Skeletal muscle regeneration depends on satellite cells. After injury these muscle stem cells exit quiescence, proliferate and differentiate to regenerate damaged fibres. We show that this progression is accompanied by metabolic changes leading to increased production of reactive oxygen species (ROS). Using Pitx2/3 single and double mutant mice that provide genetic models of deregulated redox states, we demonstrate that moderate overproduction of ROS results in premature differentiation of satellite cells while high levels lead to their senescence and regenerative failure. Using the ROS scavenger, N-Acetyl-Cysteine (NAC), in primary cultures we show that a physiological increase in ROS is required for satellite cells to exit the cell cycle and initiate differentiation through the redox activation of p38α MAP kinase. Subjecting cultured satellite cells to transient inhibition of P38α MAP kinase in conjunction with NAC treatment leads to their rapid expansion, with striking improvement of their regenerative potential in grafting experiments.

Sign in / Sign up

Export Citation Format

Share Document