Novel evidence that testosterone promotes cell proliferation and differentiation via G protein-coupled receptors in the rat L6 skeletal muscle myoblast cell line

2011 ◽  
Vol 227 (1) ◽  
pp. 98-107 ◽  
Author(s):  
Rui Fu ◽  
Jiali Liu ◽  
Jingjing Fan ◽  
Ruiguo Li ◽  
Defa Li ◽  
...  
2019 ◽  
Vol 127 (2) ◽  
pp. 342-355 ◽  
Author(s):  
Cecilie J. L. Bechshøft ◽  
Peter Schjerling ◽  
Michael Kjaer ◽  
Abigail L. Mackey

Underpinning skeletal muscle plasticity is the interplay between many cell types, of which fibroblasts are emerging as potent players, both negatively in the development of fibrosis but also positively in stimulating muscle repair through enhancing myogenesis. The mechanisms behind this interaction however remain unknown. To investigate this, waste hamstring muscle tissue was obtained from eight healthy young men undergoing reconstructive anterior cruciate ligament surgery and primary myoblasts and fibroblasts were isolated. Myoblasts were cultured alone or with fibroblasts, either in direct or indirect contact (separated by an insert with a permeable membrane). The myogenesis parameters proliferation, differentiation, and fusion were determined from immunostained cells, while, in replicate samples, gene expression levels of GAPDH, Ki67, Pax7, MyoD, myogenin, myomaker, MHC-Iβ, TCF7L2, COL1A1, and p16 were determined by RT-PCR. We found only trends for an influence of skeletal muscle fibroblasts on myogenic cell proliferation and differentiation. While greater mRNA levels of GAPDH, Pax7, MyoD, myogenin, and MHC-Iβ were observed in myogenic cells in indirect contact with fibroblasts (insert) when compared with cells cultured alone, a similar effect of an empty insert was also observed. In conclusion we find very little influence of skeletal muscle fibroblasts on myoblasts derived from the same tissue, although it cannot be excluded that a different outcome would be seen under less optimal myogenic growth conditions. NEW & NOTEWORTHY Using passage one primary myoblasts and fibroblasts isolated from human skeletal muscle, we found only a trend for an effect of skeletal muscle fibroblasts on myogenic cell proliferation and differentiation. This is contrary to previous reports and raises the possibility that fibroblasts of different tissue origins exert distinct roles.


Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 4292-4292
Author(s):  
Youshan Zhao ◽  
Feng Xu ◽  
Juan Guo ◽  
Sida Zhao ◽  
Chunkang Chang ◽  
...  

Abstract Background and Object In addition to histone deacetylation, the importance of histone over-acetylation induced oncogene transcription in initiation and progression of myelodysplastic syndrome (MDS) has been proposed recently. Our previous whole-exome sequencing identified a new somatic mutation, ANKRD11, an important factor in histone acetylation regulation. Its roles in MDS pathophysiology need to be clarified. Methods The next generation target sequencing (Including ANKRD11) was carried out in 320 patients with MDS using the MiSeq Benchtop Sequencer. ANKRD11 mRNA expression in bone marrow of MDS was measured by real-time PCR. Loss and gain of function assay were carried out in myeloid cell lines K562, MEG-01£¬or SKM-1 to observe the influence on cell proliferation and differentiation . The levels of histone acetylation at H3 and H4 were detected by Western blot. Results Target sequencing in a cohort of 320 MDS patients identified 14 of ANKRD11 mutations (4.38%, Fig.1), which were confirmed by Sanger sequencing. Meanwhile, no ANKRD11 mutations in 100 normal controls were defined. ANKRD11 mutations occurred frequently in exons 10 and 9. The mRNA expression levels of ANKRD11 were significantly decreased in MDS patients, especially in ANKRD11mutant patients (Fig.2). ANKRD11 knockdown in K562 and MEG-1 resulted in growth inhibition, cell cycle arrest and erythroid/megakaryocytic differentiation retardant. In MDS cell line SKM-1, the arrested differentiation was rescued by over-expression of ANKRD11. Consistent with a role for ANKRD11 in histone acetylation, ANKRD11 KD increased acetylation of histones H3 and H4 at H3K14 and H4K5 and resulted in the upregulation of genes involved in differentiation inhibilation (SOX6, P21, et al). Finally, the ANKRD11 KD-mediated influence on cell proliferation and differentiation were reversed by inhibiting histone acetyltransferase activity. Conclusion Our assay defined that ANKRD11 was a crucial chromatin regulator that suppress histone acetylation and then decrease gene expression during myeloid differentiation, providing a likely explanation for its role in MDS pathogenesis. This study further support histone acetylase inhibitor as a potential treatment in MDS. Figure ANKRD11mutation distribution (a) and coexist with other mutations (b). Figure. ANKRD11mutation distribution (a) and coexist with other mutations (b). Figure The mRNA expression levels of ANKRD11in our MDS (A, C) subset and GEO data (B). Figure. The mRNA expression levels of ANKRD11in our MDS (A, C) subset and GEO data (B). Changes of histone acetylation in ANKRD11-KD cell line (MEG-01). ANKRD11 KD significantly increased acetylation of histones H3 and H4 at H3K14 and H4K5. Changes of histone acetylation in ANKRD11-KD cell line (MEG-01). ANKRD11 KD significantly increased acetylation of histones H3 and H4 at H3K14 and H4K5. Disclosures No relevant conflicts of interest to declare.


2019 ◽  
Vol 97 (Supplement_3) ◽  
pp. 97-97
Author(s):  
Zong-ming Zhang ◽  
Chun-qi Gao ◽  
Hui-chao Yan ◽  
Xiu-qi Wang

Abstract Wnt/β-catenin plays a crucial role in skeletal muscle growth, but its specific mechanism still unclear. In this study, due to the distinct role of lysine in pig industry, we provided it as an entry point to investigate the role of Wnt/β-catenin in governing skeletal muscle growth. Firstly, total 18 weaned piglets were divided into three groups: control group, lysine deficiency group and lysine re-supplementation group (lysine levels added from 0.83% to 1.31% at 14 d). After 28 d experiment, all pigs were slaughtered to measure the change of Wnt/β-catenin in skeletal muscle. Secondly, satellite cell (SC) was isolated and cultured with Wnt activator, such as Wnt3a and WRN (Wnt3a, R-spondin1, Noggin) after lysine deficiency for 48 h to investigate cell proliferation and differentiation ability and the level of Wnt/β-catenin in different conditions. The results showed that compared with the control group, lysine deficiency significantly reduced longissimus dorsi muscle weight and Pax7 positive SC, and inhibited Wnt/β-catenin (P < 0.05). Fortunately, these restrictions were rescued to the control levels by lysine re-supplementation (P > 0.05). Meanwhile, compared with the lysine deficiency group, the MTT and western blotting assay showed cell proliferation ability was significantly increased with re-activated Wnt/β-catenin by re-supplemented lysine, Wnt3a or WRN (P < 0.05), respectively. Moreover, under the condition of cell differentiation, compared with the control group, cell fusion index was significantly decreased in the lysine deficiency group (P < 0.05), whereas it was significantly increased with lysine re-supplementation group, Wnt3a or WRN respective supplementation group in comparison with the lysine deficiency group (P < 0.05). In addition, compared with the lysine deficiency group, the protein levels of myogenic regulatory factors and Wnt/β-catenin pathway were also re-activated by re-supplemented lysine, Wnt3a or WRN (P < 0.05). Collectively, we found Wnt/β-catenin activation is required for porcine SC proliferation and differentiation to promote skeletal muscle growth.


2002 ◽  
Vol 282 (4) ◽  
pp. C899-C906 ◽  
Author(s):  
N. T Mesires ◽  
M. E. Doumit

Age-related changes in satellite cell proliferation and differentiation during rapid growth of porcine skeletal muscle were examined. Satellite cells were isolated from hindlimb muscles of pigs at 1, 7, 14, and 21 wk of age (4 animals/age group). Satellite cells were separated from cellular debris by using Percoll gradient centrifugation and were adsorbed to glass coverslips for fluorescent immunostaining. Positive staining for neural cell adhesion molecule (NCAM) distinguished satellite cells from nonmyogenic cells. The proportion of NCAM-positive cells (satellite cells) in isolates decreased from 1 to 7 wk of age. Greater than 77% of NCAM-positive cells were proliferating cell nuclear antigen positive at all ages studied. Myogenin-positive satellite cells decreased from 30% at 1 wk to 14% at 7 wk of age and remained at constant levels thereafter. These data indicate that a high percentage of satellite cells remain proliferative during rapid postnatal muscle growth. The reduced proportion of myogenin-positive cells during growth may reflect a decrease in the proportion of differentiating satellite cells or accelerated incorporation of myogenin-positive cells into myofibers.


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