Modulation of HOXA9 after skeletal muscle denervation and reinnervation

Abstract Background HOXA9 (Homeobox A9), whose expression is promoted by MLL1 (Mixed Lineage Leukemia 1) and WDR5 (WD-40 repeat protein 5), is a homeodomain-containing transcription factor which plays an essential role in regulating stem cell activity. HOXA9 inhibits regeneration of skeletal muscle and delays the recovery after muscle wound in aged mice, but is little known in denervated/reinnervated muscles. Methods we performed detailed time-process expression analysis on HOXA9 and its promotors, MLL1 and WDR5, in the rat gastrocnemius muscle after three types of sciatic nerve surgeries: nerve transection (denervation); end-to-end repairing (repairing); and the sham operation. Then the specific mechanisms of Hoxa9 were detected in vitro through primary satellite cells transfected respectively by pIRES2-DsRed2 empty plasmids, pIRES2-DsRed2-HOXA9 plasmids, pPLK/ GFP -Puro empty plasmids, and pPLK/GFP-Puro- HOXA9 shRNA plasmids. Results We found that HOXA9 expression was synchronous with the severity of muscle atrophy, as well as the upregulation of MLL1 and WDR5 associated with the denervation state to some extent. Indeed, experiments with primary satellite cells revealed that HOXA9 inhibited myogenic differentiation, but not destroy the differentiation potential, influenced the best-known atrophic pathways, and promoted apoptosis. Conclusion HOXA9 may play a pro-atrophic role in denervated muscle atrophy.

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Modulation of HOXA9 after skeletal muscle denervation and reinnervation

AJP Cell Physiology ◽

10.1152/ajpcell.00055.2020 ◽

2020 ◽

Vol 318 (6) ◽

pp. C1154-C1165

Author(s):

Xiaomei Lu ◽

Bingsheng Liang ◽

Shuaijie Li ◽

Zhi Chen ◽

Wenkai Chang

Keyword(s):

Skeletal Muscle ◽

Muscle Atrophy ◽

Satellite Cells ◽

Myogenic Differentiation ◽

Cell Activity ◽

Skeletal Muscle Regeneration ◽

Sham Operation ◽

Denervated Muscle ◽

Differentiation Potential

Homeobox A9 (HOXA9), the expression of which is promoted by mixed lineage leukemia 1 (MLL1) and WD-40 repeat protein 5 (WDR5), is a homeodomain-containing transcription factor that plays an essential role in regulating stem cell activity. HOXA9 has been found to inhibit skeletal muscle regeneration and delay recovery after muscle wounding in aged mice, but little is known about its role in denervated/reinnervated muscles. We performed detailed time-dependent expression analyses of HOXA9 and its promoters, MLL1 and WDR5, in rat gastrocnemius muscles after the following three types of sciatic nerve surgeries: nerve transection (denervation), end-to-end repair (repair), and sham operation (sham). Then, the specific mechanisms of HOXA9 were detected in vitro by transfecting primary satellite cells with empty pIRES2-DsRed2, pIRES2-DsRed2-HOXA9, empty pPLK/GFP-Puro, and pPLK/GFP-Puro-HOXA9 small hairpin RNA (shRNA) plasmids. We found, for the first time, that HOXA9 protein expression simultaneously increased with increasing denervated muscle atrophy severity and that upregulated MLL1 and WDR5 expression was partly associated with denervation. Indeed, in vitro experiments revealed that HOXA9 inhibited myogenic differentiation, affected the best known atrophic signaling pathways, and promoted apoptosis but did not eliminate the differentiation potential of primary satellite cells. HOXA9 may promote denervated muscle atrophy by regulating the activity of satellite cells.

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The LIM domain protein nTRIP6 modulates the dynamics of myogenic differentiation

Scientific Reports ◽

10.1038/s41598-021-92331-8 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Tannaz Norizadeh Abbariki ◽

Zita Gonda ◽

Denise Kemler ◽

Pavel Urbanek ◽

Tabea Wagner ◽

...

Keyword(s):

Skeletal Muscle ◽

Satellite Cells ◽

Muscle Regeneration ◽

Myogenic Differentiation ◽

Skeletal Muscle Regeneration ◽

Temporal Control ◽

Lim Domain ◽

Lim Domain Protein ◽

Domain Protein

AbstractThe process of myogenesis which operates during skeletal muscle regeneration involves the activation of muscle stem cells, the so-called satellite cells. These then give rise to proliferating progenitors, the myoblasts which subsequently exit the cell cycle and differentiate into committed precursors, the myocytes. Ultimately, the fusion of myocytes leads to myofiber formation. Here we reveal a role for the transcriptional co-regulator nTRIP6, the nuclear isoform of the LIM-domain protein TRIP6, in the temporal control of myogenesis. In an in vitro model of myogenesis, the expression of nTRIP6 is transiently up-regulated at the transition between proliferation and differentiation, whereas that of the cytosolic isoform TRIP6 is not altered. Selectively blocking nTRIP6 function results in accelerated early differentiation followed by deregulated late differentiation and fusion. Thus, the transient increase in nTRIP6 expression appears to prevent premature differentiation. Accordingly, knocking out the Trip6 gene in satellite cells leads to deregulated skeletal muscle regeneration dynamics in the mouse. Thus, dynamic changes in nTRIP6 expression contributes to the temporal control of myogenesis.

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KDM4A regulates myogenesis by demethylating H3K9me3 of myogenic regulatory factors

Cell Death and Disease ◽

10.1038/s41419-021-03799-1 ◽

2021 ◽

Vol 12 (6) ◽

Author(s):

Qi Zhu ◽

Feng Liang ◽

Shufang Cai ◽

Xiaorong Luo ◽

Tianqi Duo ◽

...

Keyword(s):

Skeletal Muscle ◽

Cell Proliferation ◽

Satellite Cells ◽

Muscle Development ◽

Kinase Inhibitor ◽

Myogenic Differentiation ◽

Myoblast Differentiation ◽

Proliferation And Differentiation ◽

H3k9me3 Level

AbstractHistone lysine demethylase 4A (KDM4A) plays a crucial role in regulating cell proliferation, cell differentiation, development and tumorigenesis. However, little is known about the function of KDM4A in muscle development and regeneration. Here, we found that the conditional ablation of KDM4A in skeletal muscle caused impairment of embryonic and postnatal muscle formation. The loss of KDM4A in satellite cells led to defective muscle regeneration and blocked the proliferation and differentiation of satellite cells. Myogenic differentiation and myotube formation in KDM4A-deficient myoblasts were inhibited. Chromatin immunoprecipitation assay revealed that KDM4A promoted myogenesis by removing the histone methylation mark H3K9me3 at MyoD, MyoG and Myf5 locus. Furthermore, inactivation of KDM4A in myoblasts suppressed myoblast differentiation and accelerated H3K9me3 level. Knockdown of KDM4A in vitro reduced myoblast proliferation through enhancing the expression of the cyclin-dependent kinase inhibitor P21 and decreasing the expression of cell cycle regulator Cyclin D1. Together, our findings identify KDM4A as an important regulator for skeletal muscle development and regeneration, orchestrating myogenic cell proliferation and differentiation.

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OR01-03 Thyroid Receptor Alpha Interacts with COUP-TFII in the Regulation of Postnatal Skeletal Muscle Regeneration

Journal of the Endocrine Society ◽

10.1210/jendso/bvaa046.1618 ◽

2020 ◽

Vol 4 (Supplement_1) ◽

Author(s):

Paola Aguiari ◽

Astgik Petrosyan ◽

Yan-Yun Liu ◽

Sheue-Yann Cheng ◽

Laura Perin ◽

...

Keyword(s):

Skeletal Muscle ◽

Thyroid Hormone ◽

Satellite Cells ◽

Muscle Regeneration ◽

Myogenic Differentiation ◽

Orphan Receptor ◽

Skeletal Muscle Regeneration ◽

Myoblast Differentiation ◽

Hormone Signaling

Abstract Myopathic changes, including muscular dystrophy and weakness, are commonly described in hypothyroid and hyperthyroid patients. Thyroid hormone signaling, via activation of thyroid nuclear receptors (TRs), plays an essential role in the maintenance of muscle mass, function, and regeneration. TRs are ligand-inducible transcription factors expressed in almost all tissues, including skeletal muscle. In a mouse model of Resistance to Thyroid Hormone carrying a frame-shift mutation in the TRα gene (TRα1PV)1,2 we observed skeletal muscle loss with aging and impaired skeletal muscle regeneration after injury. We recently described that TRα interacts with the nuclear orphan receptor Chicken Ovalbumin Upstream Promoter-factor II (COUP-TFII, or NR2F2), which is known to regulate myogenesis negatively and has a role in Duchenne-like Muscular Dystrophies3. We showed that COUP-TFII expression declines with age in WT mice, while the skeletal muscle of TRα1PV mice shows a sustained significantly higher expression of COUP-TFII. Our findings suggest that the TRα/COUP-TFII interaction might mediate the impaired skeletal muscle phenotype observed in TRα1PV mice. To better characterize this interaction, we isolated SC from 10 months old WT and TRα1PV mice and cultured them in vitro using novel methods established within our lab. Using siRNA probes, we next silenced COUP-TFII and characterized the cells via RNA-seq analysis. In vitro, we assessed myoblast differentiation and proliferation using differentiation assays and EdU incorporation. We observed that satellite cells from TRα1PV mice display impaired myoblast proliferation and in vitro myogenic differentiation compared to WT SCs. However, when COUP-TFII was silenced, the myogenic potential of TRα1PV satellite cells was restored, with a higher proliferation of myoblasts and a higher number of fully differentiated myotubes after 4 days of myogenic induction. RNAseq analysis on satellite cells from TRα1PV mice after COUP-TFII knockdown showed upregulation of genes involved in the myogenic pathway, such as Myod1 and Pax7, and of genes in the thyroid hormone signaling, such as Dio2. Ingenuity Pathway Analysis further showed activation of pathways regarding cell growth, differentiation, matrix remodeling along with muscle function, muscle contractility, and muscle contraction. These in vitro results suggest that by silencing COUP-TFII we promote the myogenic pathway and may further rescue the impaired phenotype of TRα1PV mice. These studies can help increase our knowledge of the mechanisms involved in thyroid hormone signaling in skeletal muscle regeneration, which will ultimately increase the possibility of designing more specific treatments for patients with thyroid hormone-induced myopathies. References: 1Milanesi, A., et al, Endocrinology 2016; 2Kaneshige, M. et al, Proc Natl Acad Sci U S 2001; 3Lee HJ, et al, Sci Rep. 2017.

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An Overview About the Biology of Skeletal Muscle Satellite Cells

Current Genomics ◽

10.2174/1389202920666190116094736 ◽

2019 ◽

Vol 20 (1) ◽

pp. 24-37 ◽

Cited By ~ 29

Author(s):

Laura Forcina ◽

Carmen Miano ◽

Laura Pelosi ◽

Antonio Musarò

Keyword(s):

Skeletal Muscle ◽

Stem Cells ◽

Satellite Cell ◽

Muscle Tissue ◽

Satellite Cells ◽

Cell Biology ◽

Regulatory Networks ◽

Myogenic Differentiation ◽

Cell Activity ◽

Quiescent State

The peculiar ability of skeletal muscle tissue to operate adaptive changes during post-natal development and adulthood has been associated with the existence of adult somatic stem cells. Satellite cells, occupying an exclusive niche within the adult muscle tissue, are considered bona fide stem cells with both stem-like properties and myogenic activities. Indeed, satellite cells retain the capability to both maintain the quiescence in uninjured muscles and to be promptly activated in response to growth or regenerative signals, re-engaging the cell cycle. Activated cells can undergo myogenic differentiation or self-renewal moving back to the quiescent state. Satellite cells behavior and their fate decision are finely controlled by mechanisms involving both cell-autonomous and external stimuli. Alterations in these regulatory networks profoundly affect muscle homeostasis and the dynamic response to tissue damage, contributing to the decline of skeletal muscle that occurs under physio-pathologic conditions. Although the clear myogenic activity of satellite cells has been described and their pivotal role in muscle growth and regeneration has been reported, a comprehensive picture of inter-related mechanisms guiding muscle stem cell activity has still to be defined. Here, we reviewed the main regulatory networks determining satellite cell behavior. In particular, we focused on genetic and epigenetic mechanisms underlining satellite cell maintenance and commitment. Besides intrinsic regulations, we reported current evidences about the influence of environmental stimuli, derived from other cell populations within muscle tissue, on satellite cell biology.

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Myogenic specification of side population cells in skeletal muscle

The Journal of Cell Biology ◽

10.1083/jcb.200202092 ◽

2002 ◽

Vol 159 (1) ◽

pp. 123-134 ◽

Cited By ~ 469

Author(s):

Atsushi Asakura ◽

Patrick Seale ◽

Adele Girgis-Gabardo ◽

Michael A. Rudnicki

Keyword(s):

Skeletal Muscle ◽

Stem Cells ◽

Satellite Cell ◽

Satellite Cells ◽

Essential Gene ◽

Side Population ◽

Stem Cell Marker ◽

Differentiation Potential ◽

Hematopoietic Stem

Skeletal muscle contains myogenic progenitors called satellite cells and muscle-derived stem cells that have been suggested to be pluripotent. We further investigated the differentiation potential of muscle-derived stem cells and satellite cells to elucidate relationships between these two populations of cells. FACS® analysis of muscle side population (SP) cells, a fraction of muscle-derived stem cells, revealed expression of hematopoietic stem cell marker Sca-1 but did not reveal expression of any satellite cell markers. Muscle SP cells were greatly enriched for cells competent to form hematopoietic colonies. Moreover, muscle SP cells with hematopoietic potential were CD45 positive. However, muscle SP cells did not differentiate into myocytes in vitro. By contrast, satellite cells gave rise to myocytes but did not express Sca-1 or CD45 and never formed hematopoietic colonies. Importantly, muscle SP cells exhibited the potential to give rise to both myocytes and satellite cells after intramuscular transplantation. In addition, muscle SP cells underwent myogenic specification after co-culture with myoblasts. Co-culture with myoblasts or forced expression of MyoD also induced muscle differentiation of muscle SP cells prepared from mice lacking Pax7 gene, an essential gene for satellite cell development. Therefore, these data document that satellite cells and muscle-derived stem cells represent distinct populations and demonstrate that muscle-derived stem cells have the potential to give rise to myogenic cells via a myocyte-mediated inductive interaction.

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Human Skeletal Muscle Cells Derived from the Orbicularis Oculi Have Regenerative Capacity for Duchenne Muscular Dystrophy

International Journal of Molecular Sciences ◽

10.3390/ijms20143456 ◽

2019 ◽

Vol 20 (14) ◽

pp. 3456

Author(s):

Yukito Yamanaka ◽

Nana Takenaka ◽

Hidetoshi Sakurai ◽

Morio Ueno ◽

Shigeru Kinoshita ◽

...

Keyword(s):

Skeletal Muscle ◽

Duchenne Muscular Dystrophy ◽

Muscular Dystrophy ◽

Myogenic Differentiation ◽

Aged Patients ◽

Differentiation Potential ◽

Myogenic Cells ◽

Orbicularis Oculi ◽

Human Skeletal Muscle Cells

Skeletal muscle stem cells (MuSCs) have been proposed as suitable candidates for cell therapy in muscular disorders since they exhibit good capacity for myogenic regeneration. However, for better therapeutic outcomes, it is necessary to isolate human MuSCs from a suitable tissue source with high myogenic differentiation. In this context, we isolated CD56+CD82+ cells from the extra eyelid tissue of young and aged patients, and tested in vitro myogenic differentiation potential. In the current study, myogenic cells derived from extra eyelid tissue were characterized and compared with immortalized human myogenic cells. We found that myogenic cells derived from extra eyelid tissue proliferated and differentiated myofibers in vitro, and restored DYSTROPHIN or PAX7 expression after transplantation with these cells in mice with Duchenne muscular dystrophy. Thus, human myogenic cells derived from extra eyelid tissue including the orbicularis oculi might be good candidates for stem cell-based therapies for treating muscular diseases.

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Study of the Expression and Function of Calcium-Sensing Receptor in Human Skeletal Muscle

International Journal of Molecular Sciences ◽

10.3390/ijms22147282 ◽

2021 ◽

Vol 22 (14) ◽

pp. 7282

Author(s):

Cecilia Romagnoli ◽

Preeti Sharma ◽

Roberto Zonefrati ◽

Gaia Palmini ◽

Elena Lucattelli ◽

...

Keyword(s):

Skeletal Muscle ◽

Satellite Cells ◽

Human Skeletal Muscle ◽

Myogenic Differentiation ◽

Physiological Role ◽

Calcium Sensing Receptor ◽

Calcium Sensing ◽

Muscle Tissues ◽

And Function

Skeletal muscle has an outstanding capacity for regeneration in response to injuries, but there are disorders in which this process is seriously impaired, such as sarcopenia. Pharmacological treatments to restore muscle trophism are not available, therefore, the identification of suitable therapeutic targets that could be useful for the treatment of skeletal reduced myogenesis is highly desirable. In this in vitro study, we explored the expression and function of the calcium-sensing receptor (CaSR) in human skeletal muscle tissues and their derived satellite cells. The results obtained from analyses with various techniques of gene and protein CaSR expression and of its secondary messengers in response to calcium (Ca2+) and CaSR drugs have demonstrated that this receptor is not present in human skeletal muscle tissues, neither in the established satellite cells, nor during in vitro myogenic differentiation. Taken together, our data suggest that, although CaSR is a very important drug target in physiology and pathology, this receptor probably does not have any physiological role in skeletal muscle in normal conditions.

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Hypoxia preconditioned bone marrow-derived mesenchymal stromal/stem cells enhance myoblast fusion and skeletal muscle regeneration

Stem Cell Research & Therapy ◽

10.1186/s13287-021-02530-3 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Karolina Archacka ◽

Iwona Grabowska ◽

Bartosz Mierzejewski ◽

Joanna Graffstein ◽

Alicja Górzyńska ◽

...

Keyword(s):

Skeletal Muscle ◽

Stem Cells ◽

Bone Marrow ◽

Satellite Cells ◽

Muscle Regeneration ◽

Myogenic Differentiation ◽

Skeletal Muscle Regeneration ◽

Hypoxic Conditions ◽

Cell Engraftment

Abstract Background The skeletal muscle reconstruction occurs thanks to unipotent stem cells, i.e., satellite cells. The satellite cells remain quiescent and localized between myofiber sarcolemma and basal lamina. They are activated in response to muscle injury, proliferate, differentiate into myoblasts, and recreate myofibers. The stem and progenitor cells support skeletal muscle regeneration, which could be disturbed by extensive damage, sarcopenia, cachexia, or genetic diseases like dystrophy. Many lines of evidence showed that the level of oxygen regulates the course of cell proliferation and differentiation. Methods In the present study, we analyzed hypoxia impact on human and pig bone marrow-derived mesenchymal stromal cell (MSC) and mouse myoblast proliferation, differentiation, and fusion. Moreover, the influence of the transplantation of human bone marrow-derived MSCs cultured under hypoxic conditions on skeletal muscle regeneration was studied. Results We showed that bone marrow-derived MSCs increased VEGF expression and improved myogenesis under hypoxic conditions in vitro. Transplantation of hypoxia preconditioned bone marrow-derived MSCs into injured muscles resulted in the improved cell engraftment and formation of new vessels. Conclusions We suggested that SDF-1 and VEGF secreted by hypoxia preconditioned bone marrow-derived MSCs played an essential role in cell engraftment and angiogenesis. Importantly, hypoxia preconditioned bone marrow-derived MSCs more efficiently engrafted injured muscles; however, they did not undergo myogenic differentiation.

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Hypoxic Preconditioned Bone Marrow-Derived Mesenchymal Stromal/Stem Cells Enhance Myoblast Fusion and Skeletal Muscle Regeneration

10.21203/rs.3.rs-474083/v1 ◽

2021 ◽

Author(s):

Karolina Archacka ◽

Iwona Grabowska ◽

Bartosz Mierzejewski ◽

Joanna Graffstain ◽

Alicja Górzyńska ◽

...

Keyword(s):

Skeletal Muscle ◽

Stem Cells ◽

Bone Marrow ◽

Satellite Cells ◽

Muscle Regeneration ◽

Myogenic Differentiation ◽

Skeletal Muscle Regeneration ◽

Hypoxic Conditions ◽

Cell Engraftment

Abstract Background: The skeletal muscle reconstruction occurs thanks to unipotent stem cells, i.e., satellite cells. The satellite cells remain quiescent and localized between myofiber sarcolemma and basal lamina. They are activated in response to muscle injury, proliferate, differentiate into myoblasts, and recreate myofibers. Many stem and progenitor cells support skeletal muscle regeneration, which could be disturbed by extensive damage, sarcopenia, cachexia, or genetic diseases like dystrophy. Many lines of evidence showed that the level of oxygen regulates the course of cell proliferation and differentiation. Methods: In the present study, we analyzed hypoxic’s impact on human and pig bone marrow-derived mesenchymal stromal cell (MSC) and mouse myoblast proliferation, differentiation, and fusion. Moreover, the influence of the transplantation of human bone marrow-derived MSCs cultured under hypoxic conditions on skeletal muscle regeneration was studied. Results: We showed that bone marrow-derived MSCs increased VEGF expression and improved myogenesis under hypoxic conditions in vitro. Transplantation of hypoxic preconditioned bone marrow-derived MSCs into injured muscles resulted in the improved cell engraftment and formation of new vessels. Conclusions: We suggested that SDF-1 and VEGF secreted by hypoxic preconditioned bone marrow-derived MSCs played an essential role in cell engraftment and angiogenesis. Importantly, hypoxic preconditioned bone marrow-derived MSCs more efficiently engrafted injured muscles, however, they did not undergo myogenic differentiation.

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