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Journal of Cellular Physiology Jun 2024Skeletal muscle injury affects the quality of life in many pathologies, including volumetric muscle loss, contusion injury, and aging. We hypothesized that the...
Skeletal muscle injury affects the quality of life in many pathologies, including volumetric muscle loss, contusion injury, and aging. We hypothesized that the nicotinamide phosphoribosyltransferase (Nampt) activator P7C3 improves muscle repair following injury. In the present study, we tested the effect of P7C3 (1-anilino-3-(3,6-dibromocarbazol-9-yl) propan-2-ol) on chemically induced muscle injury. Muscle injury was induced by injecting 50 µL 1.2% barium chloride (BaCl) into the tibialis anterior (TA) muscle in C57Bl/6J wild-type male mice. Mice were then treated with either 10 mg/kg body weight of P7C3 or Vehicle intraperitoneally for 7 days and assessed for histological, biochemical, and molecular changes. In the present study, we show that the acute BaCl-induced TA muscle injury was robust and the P7C3-treated mice displayed a significant increase in the total number of myonuclei and blood vessels, and decreased serum CK activity compared with vehicle-treated mice. The specificity of P7C3 was evaluated using Nampt mice, which did not display any significant difference in muscle repair capacity among treated groups. RNA-sequencing analysis of the injured TA muscles displayed 368 and 212 genes to be exclusively expressed in P7C3 and Veh-treated mice, respectively. There was an increase in the expression of genes involved in cellular processes, inflammatory response, angiogenesis, and muscle development in P7C3 versus Veh-treated mice. Conversely, there is a decrease in muscle structure and function, myeloid cell differentiation, glutathione, and oxidation-reduction, drug metabolism, and circadian rhythm signaling pathways. Chromatin immunoprecipitation-quantitative polymerase chain reaction (qPCR) and reverse transcription-qPCR analyses identified increased Pax7, Myf5, MyoD, and Myogenin expression in P7C3-treated mice. Increased histone lysine (H3K) methylation and acetylation were observed in P7C3-treated mice, with significant upregulation in inflammatory markers. Moreover, P7C3 treatment significantly increased the myotube fusion index in the BaCl-injured human skeletal muscle in vitro. P7C3 also inhibited the lipopolysaccharide-induced inflammatory response and mitochondrial membrane potential of RAW 264.7 macrophage cells. Overall, we demonstrate that P7C3 activates muscle stem cells and enhances muscle injury repair with increased angiogenesis.
PubMed: 38946152
DOI: 10.1002/jcp.31346 -
Genes May 2024Myogenic transcription factors with a basic helix-loop-helix (bHLH) such as MYOD, myogenin, MRF4, and MYF5 contribute to muscle differentiation and regulation. The gene...
Myogenic transcription factors with a basic helix-loop-helix (bHLH) such as MYOD, myogenin, MRF4, and MYF5 contribute to muscle differentiation and regulation. The gene located on chromosome 12 encodes for myogenic factor 5 (MYF5), which has a role in skeletal and extraocular muscle development and rib formation. Variants in were found to cause external ophthalmoplegia with rib and vertebral anomalies (EORVA), a rare recessive condition. To date, three homozygous variants in have been reported to cause EORVA in six members of four unrelated families. Here, we present a novel homozygous frameshift variant, c.596dupA p. (Asn199Lysfs*49), causing premature protein termination and presenting with external ophthalmoplegia, ptosis, and scoliosis in three siblings from a consanguineous family of Pakistani origin. With four variants now discovered, genetic testing and paediatric assessment for extra-ocular features should be considered in all cases of congenital ophthalmoplegia.
Topics: Humans; Frameshift Mutation; Male; Female; Myogenic Regulatory Factor 5; Ophthalmoplegia; Ribs; Pedigree; Spine; Child; Homozygote
PubMed: 38927634
DOI: 10.3390/genes15060699 -
Cells Jun 2024Resveratrol is a polyphenol known to have metabolic as well as circadian effects. However, there is little information regarding the metabolic and circadian effect of...
Resveratrol is a polyphenol known to have metabolic as well as circadian effects. However, there is little information regarding the metabolic and circadian effect of resveratrol on muscle cells. We sought to investigate the metabolic impact of resveratrol throughout the circadian cycle to clarify the associated signaling pathways. C2C12 myotubes were incubated with resveratrol in the presence of increasing concentrations of glucose, and metabolic and clock proteins were measured for 24 h. Resveratrol led to SIRT1, AMPK and PP2A activation. Myotubes treated with increasing glucose concentrations showed higher activation of the mTOR signaling pathway. However, resveratrol did not activate the mTOR signaling pathway, except for P70S6K and S6. In accordance with the reduced mTOR activity, resveratrol led to advanced circadian rhythms and reduced levels of pBMAL1 and CRY1. Resveratrol increased myogenin expression and advanced its rhythms. In conclusion, resveratrol activates the SIRT1-AMPK-PP2A axis, advances circadian rhythms and induces muscle development.
Topics: Resveratrol; Sirtuin 1; Animals; Mice; Muscle Fibers, Skeletal; Protein Phosphatase 2; AMP-Activated Protein Kinases; Circadian Rhythm; Signal Transduction; Cell Line; Glucose; Muscle Development; TOR Serine-Threonine Kinases
PubMed: 38920697
DOI: 10.3390/cells13121069 -
Gene Jun 2024Fibroblast growth factor receptors (Fgfrs) are involved in cell proliferation, differentiation, and migration via complex signaling pathways in different tissues. Our...
Fibroblast growth factor receptors (Fgfrs) are involved in cell proliferation, differentiation, and migration via complex signaling pathways in different tissues. Our previous studies showed that fibroblast growth factor receptor 4 (fgfr4) was detected in the most significant quantitative trait loci (QTL) for growth traits. However, studies focusing on the function of fgfr4 on the growth of bony fish are still limited. In this study, we identified seven fgfr genes in spotted sea bass (Lateolabrax maculatus) genome, namely fgfr1a, fgfr1b, fgfr2, fgfr3, fgfr4, fgfr5a, and fgfr5b. Phylogenetic analysis, syntenic analysis and gene structure analysis were conducted to further support the accuracy of our annotation and classification results. Additionally, fgfr4 showed the highest expression levels among fgfrs during the proliferation and differentiation stages of spotted sea bass myoblasts. To further study the function of fgfr4 in myogenesis, dual-fluorescence in situ hybridization (ISH) assay was conducted, and the results showed co-localization of fgfr4 with marker gene of skeletal muscle satellite cells. By treating differentiating myoblasts cultured in vitro with BLU-554, the mRNA expressions of myogenin (myog) and the numbers of myotubes formed by myoblasts increased significantly compared to negative control group. These results indicated that Fgfr4 inhibits the differentiation of myoblasts in spotted sea bass. Our findings contributed to filling a research gap on fgfr4 in bony fish myogenesis and the theoretical understanding of growth trait regulation of spotted sea bass.
PubMed: 38908457
DOI: 10.1016/j.gene.2024.148717 -
Diagnostic Pathology Jun 2024CIC-rearranged sarcomas (CRS) represent a new entity of undifferentiated small round cell sarcoma belonging to the Ewing-like sarcomas family. CRS are the most common... (Review)
Review
BACKGROUND
CIC-rearranged sarcomas (CRS) represent a new entity of undifferentiated small round cell sarcoma belonging to the Ewing-like sarcomas family. CRS are the most common type. Fusion partners for the CIC gene include DUX4, FOXO4, and the recently recognizedNUTM1. Rare cases of CIC::NUTM1 sarcoma in pediatric patients have recently been reported in brain, kidney, bone, and soft tissues. However, such cases have not been identified in the soft tissues of the limbs.
CASE PRESENTATION
We reported a case of CIC::NUTM1 sarcoma located in the right upper limb of an 18-year-old man. The tumor displayed morphologic features typical of CIC::DUX4 sarcomas, with small- to medium-sized round cells, a lobular pattern, focal spindling, myxoid stroma, and patchy necrosis. The tumor diffusely expressed NUTM1, was positive for WT1cter at weak to moderate intensity, and was focally positive for CD99, while it was negative for keratins, EMA, P40, MyoD1, myogenin, NKX2.2, BCOR, and pan-TRK. Fluorescence in situ hybridization analyses revealed cleavage of the CIC and NUTM1 genes.
CONCLUSION
CIC::NUTM1 sarcomas represent a novel molecular variant of CRS with a preference for the central nervous system and younger pediatric persons. Its morphology and phenotype may be mistaken for NUT carcinomas, and the behavior is more progressive than other forms of CRS. For this rare and newly discovered gene fusion variant, it is necessary to integrate molecular and immunohistochemical findings with morphologic features in the diagnosis of undifferentiated neoplasms.
Topics: Humans; Male; Adolescent; Soft Tissue Neoplasms; Repressor Proteins; Neoplasm Proteins; Nuclear Proteins; Biomarkers, Tumor; Oncogene Proteins, Fusion; Sarcoma; Upper Extremity; Gene Rearrangement; Homeobox Protein Nkx-2.2; In Situ Hybridization, Fluorescence; Transcription Factors; Homeodomain Proteins
PubMed: 38851744
DOI: 10.1186/s13000-024-01499-w -
Pediatric and Developmental Pathology :... Jun 2024Spindle cell/sclerosing rhabdomyosarcoma is an infrequent subtype of rhabdomyosarcoma according to the World Health Organization Classification of Soft Tissue and Bone...
Spindle cell/sclerosing rhabdomyosarcoma is an infrequent subtype of rhabdomyosarcoma according to the World Health Organization Classification of Soft Tissue and Bone Tumours, which includes a novel category of intraosseous spindle-cell rhabdomyosarcomas (ISCRMS) with :: or fusions. We report a case of ISCRMS with fusion presenting in the femur mimicking osteosarcoma in this unusual primary location. We present an 18-year-old male with relapsed widely metastatic sarcoma, morphologically identical to osteosarcoma responding poorly to chemotherapy, initially presenting in the distal femur. Sections showed a high-grade malignant neoplasm with sheets of epithelioid and spindled cells without obvious rhabdomyoblastic differentiation morphologically containing focal areas resembling new bone/osteoid formation. Molecular sequencing identified t(12;22) . The tumor cells were diffusely positive for pancytokeratin, MyoD1, and ALK by retrospective immunohistochemistry. Desmin and SATB2 were focally positive. Myogenin was negative, and INI-1 expression was retained. ISCRMS commonly involves craniofacial and pelvic bones, but rarely originates in long bones, as in this case. Initially, osteosarcoma was the primary diagnostic consideration based on distal long bone location, patient age, and evidence of osteoid formation. Distinction between the two entities may be nearly impossible on morphologic grounds alone, which presents a diagnostic pitfall without molecular or extensive immunoprofiling data.
PubMed: 38845135
DOI: 10.1177/10935266241257547 -
Virchows Archiv : An International... Jun 2024In this study, we investigate the expression of muscle markers, including the specific skeletal muscle markers myogenin and myoD1, in neuroendocrine carcinomas (NECs)....
In this study, we investigate the expression of muscle markers, including the specific skeletal muscle markers myogenin and myoD1, in neuroendocrine carcinomas (NECs). The study included 23 NECs from various sites (14 small cell NECs and 9 large cell NECs). These were stained with desmin, myogenin and myoD1. Positive staining with at least one muscle marker was observed in 14 cases (61%). 8 (35%), 8 (35%) and 11 (48%) of the cases were positive with desmin, myogenin and myoD1 respectively. In most, but not all, cases positive staining was focal generally involving < 10% of tumour cells. Expression of muscle markers is not uncommon in NECs. This represents an important diagnostic pitfall of which pathologists should be aware. In reporting this phenomenon, we speculate on the pathogenesis of this "aberrant" expression of muscle markers.
PubMed: 38833174
DOI: 10.1007/s00428-024-03838-0 -
Virchows Archiv : An International... Jun 2024Rhabdomyosarcoma (RMS) of the urinary bladder in adults and elderly is an exceptionally rare neoplasm that displays poorly differentiated solid (alveolar-like) small...
Rhabdomyosarcoma (RMS) of the urinary bladder in adults and elderly is an exceptionally rare neoplasm that displays poorly differentiated solid (alveolar-like) small cell pattern, frequently indistinguishable from small cell neuroendocrine carcinoma (SCNEC). However, the histogenesis of RMS and SCNEC and their inter-relationship have not been well studied and remained controversial. We herein analyzed 23 SCNEC and 3 small round cell RMS of the bladder for neuroendocrine (synaptophysin + chromogranin A) and myogenic (desmin + myogenin) marker expression and for TERT promoter mutations. In addition, the RMS cohort and one SCNEC that was revised to RMS were tested for gene fusions using targeted RNA sequencing (TruSight Illumina Panel which includes FOXO1 and most of RMS-related other genes). Overall, significant expression of myogenin and desmin was observed in one of 23 original SCNEC justifying a revised diagnosis to RMS. On the other hand, diffuse expression of synaptophysin was noted in 2 of the 4 RMS, but chromogranin A was not expressed in 3 RMS tested. TERT promoter mutations were detected in 15 of 22 (68%) SCNEC and in two of three (67%) assessable RMS cases, respectively. None of the four RMS cases had gene fusions. Our data highlights phenotypic and genetic overlap between SCNEC and RMS of the urinary bladder. High frequency of TERT promoter mutations in SCNEC is in line with their presumable urothelial origin. In addition, the presence of TERT promoter mutation in 2 of 3 RMS and lack of FOXO1 and other gene fusions in all 4 RMSs suggest a mucosal (urothelial) origin, probably representing extensive monomorphic rhabdomyoblastic transdifferentiation in SCNEC.
PubMed: 38833173
DOI: 10.1007/s00428-024-03835-3 -
Revista Espanola de Enfermedades... Jun 2024Adenocarcinoma accounts for 90% of malignant gastric tumours. Lymphomas, gastrointestinal stromal tumours (GIST) and other less frequent tumours account for 10%....
Adenocarcinoma accounts for 90% of malignant gastric tumours. Lymphomas, gastrointestinal stromal tumours (GIST) and other less frequent tumours account for 10%. However, rhabdomyosarcoma (RMS) remains a rare cause within the broad differential diagnosis of gastric lesions. Most cases of gastrointestinal RMS in adults are metastatic disease so primary RMS is extremely rare. A few cases reports of esophageal and gastric RMS have been published. This is a 76-year-old patient with a history of oncological oncology of poorly differentiated lung adenocarcinoma T2N1M0 in 2008 treated with surgery with no signs of recurrence. She presented to emergency with occasional episodes of melena and iron deficiency anemia for the last 3 months. The laboratory findings showed moderated anemia. Gastroscopy was performed and a prominent submucosal and ulcerated bulge was observed at the posterior wall of the gastric body and fundus. A histologic examination reveled tissue fragments composed of small round spindle-shaped cells. Tumor cells had atypical nuclei showing dense chromatin ad pale to eosinophilic cytoplasm. Immunohistochemically, the tumor was positive for AE1/3, desmin, myogenin and CD56. Patient was diagnosed with primary gastric RMS. Thoraco-abdominopelvic CT showed a locally advanced stage (T2 N1M0).
PubMed: 38832592
DOI: 10.17235/reed.2024.10538/2024 -
Redox Biology Jul 2024Cysteine, the rate-controlling amino acid in cellular glutathione synthesis is imported as cystine, by the cystine/glutamate antiporter, xCT, and subsequently reduced to...
Cysteine, the rate-controlling amino acid in cellular glutathione synthesis is imported as cystine, by the cystine/glutamate antiporter, xCT, and subsequently reduced to cysteine. As glutathione redox is important in muscle regeneration in aging, we hypothesized that xCT exerts upstream control over skeletal muscle glutathione redox, metabolism and regeneration. Bioinformatic analyses of publicly available datasets revealed that expression levels of xCT and GSH-related genes are inversely correlated with myogenic differentiation genes. Muscle satellite cells (MuSCs) isolated from Slc7a11 mice, which harbour a mutation in the Slc7a11 gene encoding xCT, required media supplementation with 2-mercaptoethanol to support cell proliferation but not myotube differentiation, despite persistently lower GSH. Slc7a11 primary myotubes were larger compared to WT myotubes, and also exhibited higher glucose uptake and cellular oxidative capacities. Immunostaining of myogenic markers (Pax7, MyoD, and myogenin) in cardiotoxin-damaged tibialis anterior muscle fibres revealed greater MuSC activation and commitment to differentiation in Slc7a11 muscle compared to WT mice, culminating in larger myofiber cross-sectional areas at 21 days post-injury. Slc7a11 mice subjected to a 5-week exercise training protocol demonstrated enhanced insulin tolerance compared to WT mice, but blunted muscle mitochondrial biogenesis and respiration in response to exercise training. Our results demonstrate that the absence of xCT inhibits cell proliferation but promotes myotube differentiation by regulating cellular metabolism and glutathione redox. Altogether, these results support the notion that myogenesis is a redox-regulated process and may help inform novel therapeutic approaches for muscle wasting and dysfunction in aging and disease.
Topics: Animals; Mice; Oxidation-Reduction; Cell Differentiation; Glutathione; Muscle, Skeletal; Amino Acid Transport System y+; Energy Metabolism; Muscle Development; Satellite Cells, Skeletal Muscle; Muscle Fibers, Skeletal; Cystine
PubMed: 38815331
DOI: 10.1016/j.redox.2024.103213