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

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.

scholarly journals The LIM domain protein nTRIP6 modulates the dynamics of myogenic differentiation

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.

scholarly journals Chlorella vulgaris Modulates Genes and Muscle-Specific microRNAs Expression to Promote Myoblast Differentiation in Culture

2019 ◽  
Vol 2019 ◽  
pp. 1-16 ◽  
Author(s):  
Nurhazirah Zainul Azlan ◽  
Yasmin Anum Mohd Yusof ◽  
Ekram Alias ◽  
Suzana Makpol
Keyword(s):  
Skeletal Muscle ◽  
Chlorella Vulgaris ◽  
Muscle Regeneration ◽  
Human Skeletal Muscle ◽  
The Elderly ◽  
Myoblast Differentiation ◽  
Gradual Decline ◽  
Proliferation And Differentiation ◽  
And Function

Background. Loss of skeletal muscle mass, strength, and function due to gradual decline in the regeneration of skeletal muscle fibers was observed with advancing age. This condition is known as sarcopenia. Myogenic regulatory factors (MRFs) are essential in muscle regeneration as its activation leads to the differentiation of myoblasts to myofibers. Chlorella vulgaris is a coccoid green eukaryotic microalga that contains highly nutritious substances and has been reported for its pharmaceutical effects. The aim of this study was to determine the effect of C. vulgaris on the regulation of MRFs and myomiRs expression in young and senescent myoblasts during differentiation in vitro. Methods. Human skeletal muscle myoblast (HSMM) cells were cultured and serial passaging was carried out to obtain young and senescent cells. The cells were then treated with C. vulgaris followed by differentiation induction. The expression of Pax7, MyoD1, Myf5, MEF2C, IGF1R, MYOG, TNNT1, PTEN, and MYH2 genes and miR-133b, miR-206, and miR-486 was determined in untreated and C. vulgaris-treated myoblasts on Days 0, 1, 3, 5, and 7 of differentiation. Results. The expression of Pax7, MyoD1, Myf5, MEF2C, IGF1R, MYOG, TNNT1, and PTEN in control senescent myoblasts was significantly decreased on Day 0 of differentiation (p<0.05). Treatment with C. vulgaris upregulated Pax7, Myf5, MEF2C, IGF1R, MYOG, and PTEN in senescent myoblasts (p<0.05) and upregulated Pax7 and MYOG in young myoblasts (p<0.05). The expression of MyoD1 and Myf5 in young myoblasts however was significantly decreased on Day 0 of differentiation (p<0.05). During differentiation, the expression of these genes was increased with C. vulgaris treatment. Further analysis on myomiRs expression showed that miR-133b, miR-206, and miR-486 were significantly downregulated in senescent myoblasts on Day 0 of differentiation which was upregulated by C. vulgaris treatment (p<0.05). During differentiation, the expression of miR-133b and miR-206 was significantly increased with C. vulgaris treatment in both young and senescent myoblasts (p<0.05). However, no significant change was observed on the expression of miR-486 with C. vulgaris treatment. Conclusions. C. vulgaris demonstrated the modulatory effects on the expression of MRFs and myomiRs during proliferation and differentiation of myoblasts in culture. These findings may indicate the beneficial effect of C. vulgaris in muscle regeneration during ageing thus may prevent sarcopenia in the elderly.

scholarly journals Bioengineered human myobundles mimic clinical responses of skeletal muscle to drugs

eLife ◽  
2015 ◽  
Vol 4 ◽  
Author(s):  
Lauran Madden ◽  
Mark Juhas ◽  
William E Kraus ◽  
George A Truskey ◽  
Nenad Bursac
Keyword(s):  
Skeletal Muscle ◽  
Acetylcholine Receptors ◽  
In Vitro Models ◽  
Calcium Handling ◽  
Muscle Tissues ◽  
Clinical Responses ◽  
And Function ◽  
Electrical Stimuli ◽  
Toxic Myopathy

Existing in vitro models of human skeletal muscle cannot recapitulate the organization and function of native muscle, limiting their use in physiological and pharmacological studies. Here, we demonstrate engineering of electrically and chemically responsive, contractile human muscle tissues (‘myobundles’) using primary myogenic cells. These biomimetic constructs exhibit aligned architecture, multinucleated and striated myofibers, and a Pax7+ cell pool. They contract spontaneously and respond to electrical stimuli with twitch and tetanic contractions. Positive correlation between contractile force and GCaMP6-reported calcium responses enables non-invasive tracking of myobundle function and drug response. During culture, myobundles maintain functional acetylcholine receptors and structurally and functionally mature, evidenced by increased myofiber diameter and improved calcium handling and contractile strength. In response to diversely acting drugs, myobundles undergo dose-dependent hypertrophy or toxic myopathy similar to clinical outcomes. Human myobundles provide an enabling platform for predictive drug and toxicology screening and development of novel therapeutics for muscle-related disorders.

scholarly journals Modulation of HOXA9 after skeletal muscle denervation and reinnervation

2020 ◽  
Author(s):  
Xiaomei Lu ◽  
Bingsheng Liang ◽  
Shuaijie Li ◽  
Zhi Chen ◽  
Wenkai Chang
Keyword(s):  
Skeletal Muscle ◽  
Muscle Atrophy ◽  
Satellite Cells ◽  
Gastrocnemius Muscle ◽  
Myogenic Differentiation ◽  
Cell Activity ◽  
Sham Operation ◽  
Differentiation Potential ◽  
Stem Cell Activity

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.

scholarly journals Modulation of HOXA9 after skeletal muscle denervation and reinnervation

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.

scholarly journals Age and prior exercise in vivo determine the subsequent in vitro molecular profile of myoblasts and nonmyogenic cells derived from human skeletal muscle

2019 ◽  
Vol 316 (6) ◽  
pp. C898-C912 ◽  
Author(s):  
Cecilie J. L. Bechshøft ◽  
Simon M. Jensen ◽  
Peter Schjerling ◽  
Jesper L. Andersen ◽  
Rene B. Svensson ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Stem Cell ◽  
Human Skeletal Muscle ◽  
Cell Function ◽  
Myogenic Differentiation ◽  
Molecular Profile ◽  
Muscle Stem Cell ◽  
Myogenic Cells

The decline in skeletal muscle regenerative capacity with age is partly attributed to muscle stem cell (satellite cell) dysfunction. Recent evidence has pointed to a strong interaction between myoblasts and fibroblasts, but the influence of age on this interaction is unknown. Additionally, while the native tissue environment is known to determine the properties of myogenic cells in vitro, how the aging process alters this cell memory has not been established at the molecular level. We recruited 12 young and 12 elderly women, who performed a single bout of heavy resistance exercise with the knee extensor muscles of one leg. Five days later, muscle biopsies were collected from both legs, and myogenic cells and nonmyogenic cells were isolated for in vitro experiments with mixed or separated cells and analyzed by immunostaining and RT-PCR. A lower myogenic fusion index was detected in the cells from the old versus young women, in association with differences in gene expression levels of key myogenic regulatory factors and senescence, which were further altered by performing exercise before tissue sampling. Coculture with nonmyogenic cells from the elderly led to a higher myogenic differentiation index compared with nonmyogenic cells from the young. These findings show that the in vitro phenotype and molecular profile of human skeletal muscle myoblasts and fibroblasts is determined by the age and exercise state of the original in vivo environment and help explain how exercise can enhance muscle stem cell function in old age.

scholarly journals KDM4A regulates myogenesis by demethylating H3K9me3 of myogenic regulatory factors

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.

scholarly journals A Cylindrical Molding Method for the Biofabrication of Plane-Shaped Skeletal Muscle Tissue

Micromachines ◽  
2021 ◽  
Vol 12 (11) ◽  
pp. 1411
Author(s):  
Minghao Nie ◽  
Ai Shima ◽  
Kenta Fukushima ◽  
Yuya Morimoto ◽  
Shoji Takeuchi
Keyword(s):  
Skeletal Muscle ◽  
Muscle Tissue ◽  
Myogenic Differentiation ◽  
Skeletal Muscle Tissue ◽  
Differentiation Markers ◽  
Animal Products ◽  
Molding Method ◽  
Muscle Tissues ◽  
Central Pillar

Muscle tissues can be fabricated in vitro by culturing myoblast-populated hydrogels. To counter the shrinkage of the myoblast-populated hydrogels during culture, a pair of anchors are generally utilized to fix the two ends of the hydrogel. Here, we propose an alternative method to counter the shrinkage of the hydrogel and fabricate plane-shaped skeletal muscle tissues. The method forms myoblast-populated hydrogel in a cylindrical cavity with a central pillar, which can prevent tissue shrinkage along the circumferential direction. By eliminating the usages of the anchor pairs, our proposed method can produce plane-shaped skeletal muscle tissues with uniform width and thickness. In experiments, we demonstrate the fabrication of plane-shaped (length: ca. 10 mm, width: 5~15 mm) skeletal muscle tissue with submillimeter thickness. The tissues have uniform shapes and are populated with differentiated muscle cells stained positive for myogenic differentiation markers (i.e., myosin heavy chains). In addition, we show the assembly of subcentimeter-order tissue blocks by stacking the plane-shaped skeletal muscle tissues. The proposed method can be further optimized and scaled up to produce cultured animal products such as cultured meat.

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

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.

Localization and function of ATP-sensitive potassium channels in human skeletal muscle

2003 ◽  
Vol 284 (2) ◽  
pp. R558-R563 ◽  
Author(s):  
Jens Jung Nielsen ◽  
Michael Kristensen ◽  
Ylva Hellsten ◽  
Jens Bangsbo ◽  
Carsten Juel
Keyword(s):  
Skeletal Muscle ◽  
Muscle Activity ◽  
Human Skeletal Muscle ◽  
Knee Extensor ◽  
Human Muscle ◽  
Functional Importance ◽  
Gradient Technique ◽  
And Function

The present study investigated the localization of ATP-sensitive K+ (KATP) channels in human skeletal muscle and the functional importance of these channels for human muscle K+ distribution at rest and during muscle activity. Membrane fractionation based on the giant vesicle technique or the sucrose-gradient technique in combination with Western blotting demonstrated that the KATP channels are mainly located in the sarcolemma. This localization was confirmed by immunohistochemical measurements. With the microdialysis technique, it was demonstrated that local application of the KATP channel inhibitor glibenclamide reduced ( P < 0.05) interstitial K+ at rest from ∼4.5 to 4.0 mM, whereas the concentration in the control leg remained constant. Glibenclamide had no effect on the interstitial K+ accumulation during knee-extensor exercise at a power output of 60 W. In contrast to in vitro conditions, the present study demonstrated that under in vivo conditions the KATP channels are active at rest and contribute to the accumulation of interstitial K+.

Sign in / Sign up

Export Citation Format

Share Document