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Medicina 2022Rhabdomyosarcoma is a malignant neoplasm of mesenchymal origin with skeletal striated muscular differentiation. It is the most common sarcoma of childhood and has four...
Rhabdomyosarcoma is a malignant neoplasm of mesenchymal origin with skeletal striated muscular differentiation. It is the most common sarcoma of childhood and has four subtypes: embryonal, alveolar, pleomorphic and spindle cell/sclerosing. Of all of them, the embryonal one is the most prevalent and presents a variant, botryoid, which usually involves hollow organs in the form of a multilobed polypoid mass. We present the case of a 27-year-old woman who consulted for vaginal bleeding and in whom colposcopy revealed a whitish polypoid lesion that was externalized through the external cervical os. Histological examination revealed cellular sectors alternated by lax, myxoid areas, together with typical isthmic-endometrial glands. The atypical spindle cell proliferation was arranged in nests, made up of ce lls with large eosinophilic cytoplasm with transverse cytoplasmic striations and eccentric nuclei with homogeneous chromatin. Areas of densely packed cells were exhibited immediately, but separated from, the intact epithelial lining by a thin layer of loose stroma (cambium layer). The immunostaining profile was positive for desmin, muscle-specific actin and myogenin, and negative for smooth muscle actin. A diagnosis of embryonal botryoid rhabdomyosarcoma of the uterine corpus was made.
Topics: Actins; Adult; Chromatin; Desmin; Female; Humans; Myogenin; Rhabdomyosarcoma; Rhabdomyosarcoma, Embryonal; Uterus
PubMed: 36220040
DOI: No ID Found -
Cells Sep 2020In this study, we investigated the effects and mechanisms of the pro-inflammatory cytokines IL-1β and TNF-α on the proliferation and commitment phases of myoblast...
In this study, we investigated the effects and mechanisms of the pro-inflammatory cytokines IL-1β and TNF-α on the proliferation and commitment phases of myoblast differentiation. C2C12 mouse myoblast cells were cultured to reach a proliferated or committed status and were incubated with these cytokines for the evaluation of cell proliferation, cyclooxygenase 2 (COX-2) expression, release of prostaglandins (PGs) and myokines, and activation of myogenic regulatory factors (MRFs). We found that inhibition of the IL-6 receptor reduced IL-1β- and TNF-α-induced cell proliferation, and that the IL-1β effect also involved COX-2-derived PGs. Both cytokines modulated the release of the myokines myostatin, irisin, osteonectin, and IL-15. TNF-α and IL-6 reduced the activity of Pax7 in proliferated cells and reduced MyoD and myogenin activity at both proliferative and commitment stages. Otherwise, IL-1β increased myogenin activity only in committed cells. Our data reveal a key role of IL-6 and COX-2-derived PGs in IL-1β and TNF-α-induced myoblast proliferation and support the link between TNF-α and IL-6 and the activation of MRFs. We concluded that IL-1β and TNF-α induce similar effects at the initial stages of muscle regeneration but found critical differences between their effects with the progression of the process, bringing new insights into inflammatory signalling in skeletal muscle regeneration.
Topics: Animals; Cell Differentiation; Cell Line; Cell Proliferation; Cyclooxygenase 2; Cyclooxygenase 2 Inhibitors; Diclofenac; Interleukin-1beta; Interleukin-6; Mice; Muscle Development; Muscle, Skeletal; Myoblasts; Prostaglandins; Receptors, Interleukin-6; Regeneration; Signal Transduction; Tumor Necrosis Factor-alpha
PubMed: 32882817
DOI: 10.3390/cells9092005 -
Scientific Reports Jun 2019Muscle differentiation is controlled by adhesion and growth factor-dependent signalling through common effectors that regulate muscle-specific transcriptional programs....
Muscle differentiation is controlled by adhesion and growth factor-dependent signalling through common effectors that regulate muscle-specific transcriptional programs. Here we report that mDiaphanous1, an effector of adhesion-dependent RhoA-signalling, negatively regulates myogenesis at the level of Myogenin expression. In myotubes, over-expression of mDia1ΔN3, a RhoA-independent mutant, suppresses Myogenin promoter activity and expression. We investigated mDia1-interacting proteins that may counteract mDia1 to permit Myogenin expression and timely differentiation. Using yeast two-hybrid and mass-spectrometric analysis, we report that mDia1 has a stage-specific interactome, including Prohibitin2, MyoD, Akt2, and β-Catenin, along with a number of proteosomal and mitochondrial components. Of these interacting partners, Prohibitin2 colocalises with mDia1 in cytoplasmic punctae in myotubes. We mapped the interacting domains of mDia1 and Phb2, and used interacting (mDia1ΔN3/Phb2 FL or mDia1ΔN3/Phb2-Carboxy) and non-interacting pairs (mDia1H + P/Phb2 FL or mDia1ΔN3/Phb2-Amino) to dissect the functional consequences of this partnership on Myogenin promoter activity. Co-expression of full-length as well as mDia1-interacting domains of Prohibitin2 reverse the anti-myogenic effects of mDia1ΔN3, while non-interacting regions do not. Our results suggest that Prohibitin2 sequesters mDia1, dampens its anti-myogenic activity and fine-tunes RhoA-mDia1 signalling to promote differentiation. Overall, we report that mDia1 is multi-functional signalling effector whose anti-myogenic activity is modulated by a differentiation-dependent interactome. The data have been deposited to the ProteomeXchange with identifier PXD012257.
Topics: Animals; Cell Differentiation; Cytoplasm; Formins; HEK293 Cells; Humans; Mice; Muscle Development; Muscle Fibers, Skeletal; Mutation; MyoD Protein; Myogenin; Prohibitins; Promoter Regions, Genetic; Protein Binding; Protein Domains; Repressor Proteins; Signal Transduction; Two-Hybrid System Techniques; rhoA GTP-Binding Protein
PubMed: 31165762
DOI: 10.1038/s41598-019-44749-4 -
Journal of Applied Physiology... Mar 2021Little is known about the molecular responses to power resistance exercise that lead to skeletal muscle remodeling and enhanced athletic performance. We assessed the...
Little is known about the molecular responses to power resistance exercise that lead to skeletal muscle remodeling and enhanced athletic performance. We assessed the expression of titin-linked putative mechanosensing proteins implicated in muscle remodeling: muscle ankyrin repeat proteins (Ankrd 1, Ankrd 2, and Ankrd 23), muscle-LIM proteins (MLPs), muscle RING-finger protein-1 (MuRF-1), and associated myogenic proteins (MyoD1, myogenin, and myostatin) in skeletal muscle in response to power resistance exercise with or without a postexercise meal, in fed, resistance-trained men. A muscle sample was obtained from the vastus lateralis of seven healthy men on separate days, 3 h after 90 min of rest (Rest) or power resistance exercise with (Ex + Meal) or without (Ex) a postexercise meal to quantify mRNA and protein levels. The levels of phosphorylated HSP27 (pHSP27-Ser15) and cytoskeletal proteins in muscle and creatine kinase activity in serum were also assessed. The exercise increased ( ≤ 0.05) pHSP27-Ser15 (∼6-fold) and creatine kinase (∼50%), whereas cytoskeletal protein levels were unchanged ( > 0.05). Ankrd 1 (∼15-fold) and MLP (∼2-fold) mRNA increased, whereas Ankrd 2, Ankrd 23, MuRF-1, MyoD1, and myostatin mRNA were unchanged. Ankrd 1 (∼3-fold, Ex) and MLPb (∼20-fold, Ex + Meal) protein increased, but MLPa, Ankrd 2, Ankrd 23, and the myogenic proteins were unchanged. The postexercise meal did not affect the responses observed. Power resistance exercise, as performed in practice, induced subtle early responses in the expression of MLP and Ankrd 1 yet had little effect on the other proteins investigated. These findings suggest possible roles for MLP and Ankrd 1 in the remodeling of skeletal muscle in individuals who regularly perform this type of exercise. This is the first study to assess the early changes in the expression of titin-linked putative mechanosensing proteins and associated myogenic regulatory factors in skeletal muscle after power resistance exercise in fed, resistance-trained men. We report that power resistance exercise induces subtle early responses in the expression of Ankrd 1 and MLP, suggesting these proteins play a role in the remodeling of skeletal muscle in individuals who regularly perform this type of exercise.
Topics: Connectin; Exercise; Humans; Male; Muscle, Skeletal; Myogenin; Resistance Training
PubMed: 33356984
DOI: 10.1152/japplphysiol.00711.2020 -
Journal of Cachexia, Sarcopenia and... Oct 2021Ctns mice, a mouse model of infantile nephropathic cystinosis, exhibit hypermetabolism with adipose tissue browning and profound muscle wasting. Inflammatory cytokines...
BACKGROUND
Ctns mice, a mouse model of infantile nephropathic cystinosis, exhibit hypermetabolism with adipose tissue browning and profound muscle wasting. Inflammatory cytokines such as interleukin (IL)-1 trigger inflammatory cascades and may be an important cause for cachexia. We employed genetic and pharmacological approaches to investigate the effects of IL-1 blockade in Ctns mice.
METHODS
We generated Ctns Il1β mice, and we treated Ctns and wild-type control mice with IL-1 receptor antagonist, anakinra (2.5 mg/kg/day, IP) or saline as vehicle for 6 weeks. In each of these mouse lines, we characterized the cachexia phenotype consisting of anorexia, loss of weight, fat mass and lean mass, elevation of metabolic rate, and reduced in vivo muscle function (rotarod activity and grip strength). We quantitated energy homeostasis by measuring the protein content of uncoupling proteins (UCPs) and adenosine triphosphate in adipose tissue and skeletal muscle. We measured skeletal muscle fiber area and intramuscular fatty infiltration. We also studied expression of molecules regulating adipose tissue browning and muscle mass metabolism. Finally, we evaluated the impact of anakinra on the muscle transcriptome in Ctns mice.
RESULTS
Skeletal muscle expression of IL-1β was significantly elevated in Ctns mice relative to wild-type control mice. Cachexia was completely normalized in Ctns Il1β mice relative to Ctns mice. We showed that anakinra attenuated the cachexia phenotype in Ctns mice. Anakinra normalized UCPs and adenosine triphosphate content of adipose tissue and muscle in Ctns mice. Anakinra attenuated aberrant expression of beige adipose cell biomarkers (UCP-1, CD137, Tmem26, and Tbx1) and molecules implicated in adipocyte tissue browning (Cox2/Pgf2α, Tlr2, Myd88, and Traf6) in inguinal white adipose tissue in Ctns mice. Moreover, anakinra normalized gastrocnemius weight and fiber size and attenuated muscle fat infiltration in Ctns mice. This was accompanied by correction of the increased muscle wasting signalling pathways (increased protein content of ERK1/2, JNK, p38 MAPK, and nuclear factor-κB p65 and mRNA expression of Atrogin-1 and Myostatin) and the decreased myogenesis process (decreased mRNA expression of MyoD and Myogenin) in the gastrocnemius muscle of Ctns mice. Previously, we identified the top 20 differentially expressed skeletal muscle genes in Ctns mice by RNAseq. Aberrant expression of these 20 genes have been implicated in muscle wasting, increased energy expenditure, and lipolysis. We showed that anakinra attenuated 12 of those top 20 differentially expressed muscle genes in Ctns mice.
CONCLUSIONS
Anakinra may provide a targeted novel therapy for patients with infantile nephropathic cystinosis.
Topics: Animals; Cachexia; Cystinosis; Humans; Mice; Muscle, Skeletal; Muscular Atrophy
PubMed: 34196133
DOI: 10.1002/jcsm.12744 -
Aging and Disease Sep 2015Muscle denervation at the neuromuscular junction (NMJ) is thought to be a contributing factor in age-related muscle weakness. Therefore, understanding the mechanisms... (Review)
Review
Muscle denervation at the neuromuscular junction (NMJ) is thought to be a contributing factor in age-related muscle weakness. Therefore, understanding the mechanisms that modulate NMJ innervation is a key to developing therapies to combat age-related muscle weakness affecting the elderly. Two mouse models, one lacking the Cu/Zn superoxide dismutase (SOD1) gene and another harboring the transgenic mutant human SOD1 gene, display progressive changes at the NMJ, including muscle endplate fragmentation, nerve terminal sprouting, and denervation. These changes at the NMJ share many of the common features observed in the NMJs of aged mice. In this review, research findings demonstrating the effects of PGC-1α, IGF-1, GDNF, MyoD, myogenin, and miR-206 on NMJ innervation patterns in the G93A SOD1 mice will be highlighted in the context of age-related muscle denervation.
PubMed: 26425392
DOI: 10.14336/AD.2015.0506 -
Journal of Microbiology and... Dec 2023Muscle atrophy, which is defined as a decrease in muscle mass and strength, is caused by an imbalance between the anabolism and catabolism of muscle proteins. Thus,...
Muscle atrophy, which is defined as a decrease in muscle mass and strength, is caused by an imbalance between the anabolism and catabolism of muscle proteins. Thus, modulating the homeostasis between muscle protein synthesis and degradation represents an efficient treatment approach for this condition. In the present study, the protective effects against muscle atrophy of ethanol extracts of L. (MA) and Koidz. (AK) leaves and their mixtures (MIX) were evaluated in vitro and in vivo. Our results showed that MIX increased 5-aminoimidazole-4-carboxamide ribonucleotide-induced C2C12 myotube thinning, and enhanced soleus and gastrocnemius muscle thickness compared to each extract alone in dexamethasone-induced muscle atrophy Sprague Dawley rats. In addition, although MA and AK substantially improved grip strength and histological changes for dexamethasone-induced muscle atrophy in vivo, the efficacy was superior in the MIX-treated group. Moreover, MIX further increased the expression levels of myogenic factors (MyoD and myogenin) and decreased the expression levels of E3 ubiquitin ligases (atrogin-1 and muscle-specific RING finger protein-1) in vitro and in vivo compared to the MA- and AK-alone treatment groups. Furthermore, MIX increased the levels of phosphorylated phosphoinositide 3-kinase (PI3K), protein kinase B (Akt), and mammalian target of rapamycin (mTOR) that were reduced by dexamethasone, and downregulated the expression of forkhead box O3 (FoxO3a) induced by dexamethasone. These results suggest that MIX has a protective effect against muscle atrophy by enhancing muscle protein anabolism through the activation of the PI3K/Akt/mTOR signaling pathway and attenuating catabolism through the inhibition of FoxO3a.
Topics: Rats; Animals; Proto-Oncogene Proteins c-akt; Phosphatidylinositol 3-Kinases; Phosphatidylinositol 3-Kinase; Angelica; Rats, Sprague-Dawley; Muscular Atrophy; Signal Transduction; Muscle, Skeletal; TOR Serine-Threonine Kinases; Muscle Proteins; Dexamethasone; Mammals
PubMed: 37674382
DOI: 10.4014/jmb.2306.06012 -
Journal of Cachexia, Sarcopenia and... Aug 2018Skeletal muscle is characterized by an efficient regeneration potential that is often impaired during myopathies. Understanding the molecular players involved in muscle...
BACKGROUND
Skeletal muscle is characterized by an efficient regeneration potential that is often impaired during myopathies. Understanding the molecular players involved in muscle homeostasis and regeneration could help to find new therapies against muscle degenerative disorders. Previous studies revealed that the Ser/Thr kinase p21 protein-activated kinase 1 (Pak1) was specifically down-regulated in the atrophying gastrocnemius of Yoshida hepatoma-bearing rats. In this study, we evaluated the role of group I Paks during cancer-related atrophy and muscle regeneration.
METHODS
We examined Pak1 expression levels in the mouse Tibialis Anterior muscles during cancer cachexia induced by grafting colon adenocarcinoma C26 cells and in vitro by dexamethasone treatment. We investigated whether the overexpression of Pak1 counteracts muscle wasting in C26-bearing mice and in vitro also during interleukin-6 (IL6)-induced or dexamethasone-induced C2C12 atrophy. Moreover, we analysed the involvement of group I Paks on myogenic differentiation in vivo and in vitro using the group I chemical inhibitor IPA-3.
RESULTS
We found that Pak1 expression levels are reduced during cancer-induced cachexia in the Tibialis Anterior muscles of colon adenocarcinoma C26-bearing mice and in vitro during dexamethasone-induced myotube atrophy. Electroporation of muscles of C26-bearing mice with plasmids directing the synthesis of PAK1 preserves fiber size in cachectic muscles by restraining the expression of atrogin-1 and MuRF1 and possibly by inducing myogenin expression. Consistently, the overexpression of PAK1 reduces the dexamethasone-induced expression of MuRF1 in myotubes and increases the phospho-FOXO3/FOXO3 ratio. Interestingly, the ectopic expression of PAK1 counteracts atrophy in vitro by restraining the IL6-Stat3 signalling pathway measured in luciferase-based assays and by reducing rates of protein degradation in atrophying myotubes exposed to IL6. On the other hand, we observed that the inhibition of group I Paks has no effect on myotube atrophy in vitro and is associated with impaired muscle regeneration in vivo and in vitro. In fact, we found that mice treated with the group I inhibitor IPA-3 display a delayed recovery from cardiotoxin-induced muscle injury. This is consistent with in vitro experiments showing that IPA-3 impairs myogenin expression and myotube formation in vessel-associated myogenic progenitors, C2C12 myoblasts, and satellite cells. Finally, we observed that IPA-3 reduces p38α/β phosphorylation that is required to proceed through various stages of satellite cells differentiation: activation, asymmetric division, and ultimately myotube formation.
CONCLUSIONS
Our data provide novel evidence that is consistent with group I Paks playing a central role in the regulation of muscle homeostasis, atrophy and myogenesis.
Topics: Animals; Cachexia; Cell Differentiation; Cell Line, Tumor; Cell Proliferation; Cytokines; Disease Models, Animal; Gene Expression; Male; Mice; Muscle Fibers, Skeletal; Muscle, Skeletal; Muscular Atrophy; Myoblasts; Myogenin; Neoplasms; Phosphorylation; Regeneration; Satellite Cells, Skeletal Muscle; p21-Activated Kinases; p38 Mitogen-Activated Protein Kinases
PubMed: 29781585
DOI: 10.1002/jcsm.12303 -
ELife Oct 2021Non-centrosomal microtubule-organizing centers (MTOCs) are pivotal for the function of multiple cell types, but the processes initiating their formation are unknown....
Non-centrosomal microtubule-organizing centers (MTOCs) are pivotal for the function of multiple cell types, but the processes initiating their formation are unknown. Here, we find that the transcription factor myogenin is required in murine myoblasts for the localization of MTOC proteins to the nuclear envelope. Moreover, myogenin is sufficient in fibroblasts for nuclear envelope MTOC (NE-MTOC) formation and centrosome attenuation. Bioinformatics combined with loss- and gain-of-function experiments identified induction of AKAP6 expression as one central mechanism for myogenin-mediated NE-MTOC formation. Promoter studies indicate that myogenin preferentially induces the transcription of muscle- and NE-MTOC-specific isoforms of and , which encodes nesprin-1α, the NE-MTOC anchor protein in muscle cells. Overexpression of AKAP6β and nesprin-1α was sufficient to recruit endogenous MTOC proteins to the nuclear envelope of myoblasts in the absence of myogenin. Taken together, our results illuminate how mammals transcriptionally control the switch from a centrosomal MTOC to an NE-MTOC and identify AKAP6 as a novel NE-MTOC component in muscle cells.
Topics: 3T3 Cells; A Kinase Anchor Proteins; Animals; Cell Line; HEK293 Cells; Humans; Mice; Microtubule-Organizing Center; Muscle Cells; Myogenin; Nuclear Envelope
PubMed: 34605406
DOI: 10.7554/eLife.65672 -
Cells Oct 2022Muscle injuries, degenerative diseases and other lesions negatively affect functioning of human skeletomuscular system and thus quality of life. Therefore, the...
Muscle injuries, degenerative diseases and other lesions negatively affect functioning of human skeletomuscular system and thus quality of life. Therefore, the investigation of molecular mechanisms, stimulating myogenic differentiation of primary skeletal-muscle-derived mesenchymal stem/stromal cells (SM-MSCs), is actual and needed. The aim of the present study was to investigate the myogenic differentiation of CD56 (neural cell adhesion molecule, NCAM)-positive and -negative SM-MSCs and their response to the non-cytotoxic heat stimulus. The SM-MSCs were isolated from the post operation muscle tissue, sorted by flow cytometer according to the CD56 biomarker and morphology, surface profile, proliferation and myogenic differentiation has been investigated. Data show that CD56(+) cells were smaller in size, better proliferated and had significantly higher levels of CD146 (MCAM) and CD318 (CDCP1) compared with the CD56(-) cells. At control level, CD56(+) cells significantly more expressed myogenic differentiation markers and myogenin ( and better differentiated to the myogenic direction. The non-cytotoxic heat stimulus significantly stronger stimulated expression of myogenic markers in CD56(+) than in CD56(-) cells that correlated with the multinucleated cell formation. Data show that regenerative properties of CD56(+) SM-MSCs can be stimulated by an extracellular stimulus and be used as a promising skeletal muscle regenerating tool in vivo.
Topics: Humans; Myogenin; CD146 Antigen; Quality of Life; Mesenchymal Stem Cells; Muscle, Skeletal; Heat-Shock Response; Biomarkers; Neural Cell Adhesion Molecules; Antigens, Neoplasm; Cell Adhesion Molecules
PubMed: 36291076
DOI: 10.3390/cells11203209