207 Satellite Cells Participate in the wnt/ca2+ Pathway Controlled Porcine Myofiber Determination

2021 ◽  
Vol 99 (Supplement_3) ◽  
pp. 110-110
Author(s):  
Mao Ye ◽  
Zhiwen Song ◽  
Chenglong Jin ◽  
Chunqi Gao ◽  
Huichao Yan ◽  
...  

Abstract The type of myofiber is important for porcine meat quality. Meanwhile, the nt/Ca2+ pathway has been showed multiple roles in skeletal muscle formation; however, the distinct mechanism is still unclear. In this study, the weaned piglets and satellite cells were designed into the control group, lysine deficiency group and lysine rescue group to investigate the function of Wnt/Ca2+ pathway in governing skeletal muscle typing. After we confirm the growth of weaned piglets was controlled by lysine, the isobaric tag for relative and absolute quantification (iTRAQ) analysis of skeletal muscle detected that Wnt/Ca2+ pathway was involved in the transition of fast and slow fiber. Then, we found the ratio of type I myofiber in Semimembranous (fast muscle) was significantly increased after lysine deficiency (P < 0.05), and decreased by lysine rescue (P < 0.05). In contrast, the ratio of type I myofiber in Semitendinous muscle (slow muscle) was significantly decreased in the lysine deficiency group, and increased in the lysine rescue group (P < 0.05). Furthermore, the Wnt/Ca2+ pathway was significantly increased in Semimembranous muscle, while decreased in Semitendinous muscle with lysine deficiency, and this phenomenon was inversed after lysine rescue (P < 0.05). Meanwhile, the Wnt/Ca2+ pathway was stronger in satellite cells isolated from Semitendinous muscle (StSCs) than that of Semimembranous satellite cell (SmSCs) (P < 0.05). And we also found the StSCs enter in differentiation is more easily than SmSCs (P < 0.05). Besides, the ratio of type I myofiber originated from StSCs showed greater than StSCs (P < 0.05). In summary, we conclude that satellite cells participate in the Wnt/Ca2+ pathway controlled porcine myofiber determination.

2014 ◽  
Author(s):  
◽  
Danny A. Stark

[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT AUTHOR'S REQUEST.] Skeletal muscle can be isolated into 642 individual muscles and makes up to one third to one half of the mass of the human body. Each of these muscles is specified and patterned prenatally and after birth they will increase in size and take on characteristics suited to each muscle's unique function. To make the muscles functional, each muscle cell must be innervated by a motor neuron, which will also affect the characteristics of the mature muscle. In a healthy adult, muscles will maintain their specialized pattern and function during physiological homeostasis, and will also recapitulate them if the integrity or health of the muscle is disrupted. This repair and regeneration is dependent satellite cells, the skeletal muscle stem cells. In this dissertation, we study a family of receptor tyrosine kinases, Ephs, and their juxtacrine ephrin ligands in the context of skeletal muscle specification and regeneration. First, using a classical ephrin 'stripe' assay to test for contact-mediated repulsion, we found that satellite cells respond to a subset of ephrins with repulsive motility in vitro and that these forward signals through Ephs also promote patterning of differentiating myotubes parallel to ephrin stripes. This pattering can be replicated in a heterologous in vivo system (the hindbrain of the developing quail, where neural crest cells migrate in streams to the branchial arches, and in the forelimb of the developing quail, where presumptive limb myoblasts emigrate from the somite). Second, we present evidence that specific pairwise interactions between Eph receptor tyrosine kinases and ephrin ligands are required to ensure appropriate muscle innervation when it is originally set during postnatal development and when it is recapitulated after muscle or nerve trauma during adulthood. We show expression of a single ephrin, ephrin-A3, exclusively on type I (slow) myofibers shortly after birth, while its receptor EphA8 is only localized to fast motor endplates, suggesting a functional repulsive interaction for motor axon guidance and/or synaptogenesis. Adult EFNA3-/- mutant mice show a significant loss of slow myofibers, while misexpression of ephrin-A3 on fast myofibers results in a switch from a fast fiber type to slow in the context of sciatic nerve injury and regrowth. Third, we show that EphA7 is expressed on satellite cell derived myocytes in vitro, and marks both myocytes and regenerating myofibers in vivo. In the EPHA7 knockout mouse, we find a regeneration defect in a barium chloride injury model starting 3 days post injection in vivo, and that cultured mutant satellite cells are slow to differentiate and divide. Finally, we present other potential Ephs and ephrins that may affect skeletal muscle, such as EphB1 that is expressed on all MyHC-IIb fibers and a subset of MyHC-IIx fibers, and we show a multitude of Ephs and ephrins at the neuromuscular junction that appear to localize on specific myofibers and at different areas of the synapse. We propose that Eph/ephrin signaling, though well studied in development, continues to be important in regulating post natal development, regeneration, and homeostasis of skeletal muscle.


2007 ◽  
Vol 293 (2) ◽  
pp. C661-C669 ◽  
Author(s):  
Catherine Alexakis ◽  
Terence Partridge ◽  
George Bou-Gharios

Because of its mechanical function, skeletal muscle is heavily influenced by the composition of its extracellular matrix (ECM). Fibrosis generated by chronic damage, such as occurs in muscular dystrophies, is thus particularly disastrous in this tissue. Here, we examined the interrelationship between the muscle satellite cell and the production of collagen type I, a major component of fibrotic ECM, by using both C2C12, a satellite cell-derived cell line, and primary muscle satellite cells. In C2C12 cells, we found that expression of collagen type I mRNA decreases substantially during skeletal muscle differentiation. On a single-cell level, collagen type I and myogenin became mutually exclusive after 3 days in differentiation medium, whereas addition of collagen markedly suppressed differentiation of C2C12 cells. Primary cultures of satellite cells associated with isolated single fibers of the young (4 wk old) mdx dystrophic mouse and of C57BL/10ScSn wild-type controls expressed collagen type I and type III mRNA and protein. This pattern persisted in wild-type mice at all ages. But, curiously, in older (18-mo-old) mdx mice, although the myogenic cells continued to express type III collagen, type I expression became restricted to nonmyogenic cells. These cells typically constituted part of a cellular sheet surrounding the old mdx fibers. This combination of features strongly suggests that the progression to fibrosis in dystrophic muscle involves changes in the mechanisms controlling matrix production, which generates positive feedback that results in a reprogramming of myoblasts to a profibrotic function.


2018 ◽  
Vol 125 (5) ◽  
pp. 1536-1554 ◽  
Author(s):  
Mette Flindt Heisterberg ◽  
Jesper L. Andersen ◽  
Peter Schjerling ◽  
Alberte Lund ◽  
Simone Dalskov ◽  
...  

Our purpose here was to investigate the potential of blocking the angiotensin II type I receptor (AT1R) on the hypertrophy response of elderly human skeletal muscle to 4 mo of heavy-resistance exercise training. Fifty-eight healthy elderly men (+65 yr) were randomized into three groups, consuming either AT1R blocker (losartan, 100 mg/day) or placebo for 4 mo. Two groups performed resistance training (RT) and were treated with either losartan or placebo, and one group did not train but was treated with losartan. Quadriceps muscle biopsies, MR scans, and strength tests were performed at baseline and after 8 and 16 wk. Biopsies were sectioned for immunohistochemistry to determine the number of satellite cells, capillaries, fiber type distribution, and fiber area. Gene expression levels of myostatin, connective tissue, and myogenic signaling pathways were determined by real-time RT-PCR. Four months of heavy-resistance training led in both training groups to expected improvements in quadriceps (∼3–4%) and vastus lateralis (∼5–6%), cross-sectional area, and type II fiber area (∼10–18%), as well as dynamic (∼13%) and isometric (∼19%) quadriceps peak force, but with absolutely no effect of losartan on these outcomes. Furthermore, no changes were seen in satellite cell number with training, and most gene targets failed to show any changes induced by training or losartan treatment. We conclude that there does not appear to be any effect of AT1R blocking in elderly men during 4 mo of resistance training. Therefore, we do not find any support for using AT1R blockers for promoting muscle adaptation to training in humans. NEW & NOTEWORTHY Animal studies have suggested that blocking angiotensin II type I receptor (AT1R) enhances muscle regeneration and prevents disuse atrophy, but studies in humans are limited. Focusing on hypertrophy, satellite cells, and gene expression, we found that AT1R blocking did not result in any greater responses with 4 mo of resistance training. These results do not support previous findings and question the value of blocking AT1R in the context of preserving aging human muscle.


F1000Research ◽  
2017 ◽  
Vol 6 ◽  
pp. 1958 ◽  
Author(s):  
Ivan Nombela ◽  
Sara Puente-Marin ◽  
Veronica Chico ◽  
Alberto J. Villena ◽  
Begoña Carracedo ◽  
...  

Background:It has been described that fish nucleated red blood cells (RBCs) generate a wide variety of immune-related gene transcripts when viruses highly replicate inside them and are their main target cell. The immune response and mechanisms of fish RBCs against viruses targeting other cells or tissues has not yet been explored and is the objective of our study.Methods:Trout RBCs were obtained from peripheral blood, ficoll purified and exposed toViral Haemorrhagic Septicaemia virus(VHSV). Immune response was evaluated by means of RT-qPCR, flow cytometry, immunofluorescence and isobaric tag for relative and absolute quantification (iTRAQ) protein profilingResults:VHSV N gene transcripts incremented early postexposure and were drastically decreased after 6 hours postexposure (hpe). The expression of the type I interferon (ifn1) gene was significantly downregulated at early postexposure (3 hpe), together with a gradual downregulation of interferon-induciblemxandpkrgenes until 72 hpe. Type I IFN protein was downregulated and interferon-inducible Mx protein was maintained at basal levels. Co-culture assays of RBCs with TSS (stromal cell line from spleen) revealed the IFN crosstalk between both cell types. On the other hand, anti-microbial peptide β-defensin 1 and neutrophil chemotactic factor interleukin 8 were slightly upregulated in VHSV-exposed RBCs Isobaric tag for relative and absolute quantification (iTRAQ) revealed that VHSV exposure can induce a global protein downregulation in trout RBCs, mainly related to RNA stability and proteasome pathways. The antioxidant/antiviral response is also suggested to be involved in the response of trout RBCs to VHSV.Conclusions:A variety of mechanisms are proposed to be implicated in the antiviral response of trout RBCs against VHSV halted infection. Ongoing research is focused on understanding the mechanisms in detail. To our knowledge, this is the first report that implicates fish RBCs in the antiviral response against viruses not targeting RBCs.


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.


1991 ◽  
Vol 260 (2) ◽  
pp. E272-E279 ◽  
Author(s):  
R. M. McAllister ◽  
R. W. Ogilvie ◽  
R. L. Terjung

Functional and metabolic responses of hypothyroid skeletal muscle were evaluated during steady-state isometric contraction conditions, using an isolated perfused rat hindlimb preparation. Treating rats with propylthiouracil (PTU) for 4-5 mo resulted in a 55% decrease (P less than 0.001) in citrate synthase activity in plantaris muscle and phenotypic remodeling of the plantaris, evident by a threefold increase in type I fiber area and a 13% decrease in type II fiber area. Perfusion of PTU (n = 9) and control (n = 9) rat hindlimbs of similar size, with similar inflow (approximately 10 ml/min) and oxygen content (approximately 20 g/100 ml), resulted in similar oxygen deliveries to the contracting muscles (PTU 11.4 +/- 0.58, control 9.54 +/- 0.75 mumol.min-1.g-1; P greater than 0.05). Ten-minute tetanic contraction (100 ms at 100 Hz) periods at 4, 8, 15, 30, and 45 tetani/min were elicited in consecutive ascending order. Oxygen consumption (VO2) was lower in the PTU group at all contraction frequencies (P less than 0.005), with a decrease in peak VO2 of 44% (PTU 3.01 +/- 0.29, control 5.35 +/- 0.42 mumol.min-1.g-1; P less than 0.001). Oxygen extraction by the PTU muscle was only approximately 25% of that delivered. Developed tension was initially less (15%; P less than 0.05) in the PTU group but declined in a similar manner, as a percent of initial, to that of the control group. The slightly lower absolute tension development of the PTU muscle could not account for the large reduction in VO2.(ABSTRACT TRUNCATED AT 250 WORDS)


1995 ◽  
Vol 268 (3) ◽  
pp. E453-E457 ◽  
Author(s):  
M. S. Hickey ◽  
J. O. Carey ◽  
J. L. Azevedo ◽  
J. A. Houmard ◽  
W. J. Pories ◽  
...  

The purpose of this study was to determine if a relationship exists among skeletal muscle fiber composition, adiposity, and in vitro muscle glucose transport rate in humans. Rectus abdominus muscle was obtained during elective abdominal surgery from nonobese control (n = 12), obese (n = 12), and obese non-insulin-dependent diabetes mellitus (NIDDM) patients (n = 10). The obese NIDDM group had a significantly lower percentage of type I muscle fibers (32.2 +/- 1.9%) than the obese group (40.4 +/- 2.7%), and both obese groups were significantly lower than the control group (50.0 +/- 2.6%). Insulin-stimulated glucose transport, determined on 28 subjects, was significantly lower in both the obese (3.83 +/- 0.48 nmol.min-1.mg-1) and NIDDM (3.93 +/- 1.0 nmol.min-1.mg-1) groups vs. the control group (7.35 +/- 1.50 nmol.min-1.mg-1). Body mass index (BMI) was inversely correlated to percent type I fibers (r = -0.50, P < 0.01) and to the insulin-stimulated glucose transport rate (r = -0.53, P < 0.01). The percentage of type I muscle fibers was related to the insulin-stimulated glucose transport rate (r = 0.57, P < 0.01), although this relationship was not significant after adjusting for BMI. Although these data do not support an independent relationship between fiber type and insulin action in obesity, a reduced skeletal muscle type I fiber population may be one component of a multifactorial process involved in the development of insulin resistance.


Author(s):  
R. Wróblewski ◽  
W. Gremski ◽  
G. M. Roomans ◽  
R. Nordemar ◽  
L. Edström

Many diseases of the human skeletal muscle involve an atrophy of the muscle fibres. In some cases mainly one of the fibre types is affected. The fibre typing system used in this study is that of Padykula and Herman, 1955 and distinguishes between type I fibres which presumably correspond to the slow-twitch fibres and type II fibres which are the fast-twitch fibres. The type II fibres can be divided into type II A, II B and II C fibres. Recent advances in instrumentation and tissue preparation have permitted an investigation of the elemental composition of individual muscle fibres of known fibre type with the aim of comparing healthy and atrophied muscle fibres.In this study we have examined ten patients suffering from rheumatoid arthritis, two patients suffering from Parkinson's disease and two patients with upper motor lesions. As a control group we have examined muscles from eight healthy controls of the same age.


1987 ◽  
Vol 116 (3) ◽  
pp. 425-432 ◽  
Author(s):  
Michael V. Dodson ◽  
Ronald E. Allen ◽  
Nobuyoshi Shimizu ◽  
Yoshiko Shimizu ◽  
Kim L. Hossner

Abstract. The interactions of 125I-multiplication stimulating activity (MSA) and 125I-ovine somatomedin with receptors on skeletal muscle satellite cells are described. Specific binding of 125I-MSA/rIGF-II was inhibited by MSA/rIGF-II and oSm but not by insulin. Binding of 125I-oSm was inhibited by MSA/rIGF-II, oSm and insulin. In addition, 24-h pre-incubation of satellite cells with insulin increased the amount of 125I-MSA/rIGF-II bound, but insulin concentrations below 550 μg/l had no effect on the subsequent binding of 125I-oSm. Pre-incubation of cultures with oSm or MSA/rIGF-II decreased the subsequent binding of 125I-oSm and 125I-MSA/rIGF-II. These preliminary experiments suggest that oSm is similar to IGF-I in its binding characteristics and that primary cultures of skeletal muscle satellite cells possess type I and type II IGF receptors.


2001 ◽  
Vol 280 (4) ◽  
pp. R1256-R1260 ◽  
Author(s):  
Espen E. Spangenburg ◽  
Jay H. Williams ◽  
Roland R. Roy ◽  
Robert J. Talmadge

Calcineurin (CaN) has been implicated as a signaling molecule that can transduce physiological stimuli (e.g., contractile activity) into molecular signals that initiate slow-fiber phenotypic gene expression and muscle growth. To determine the influence of muscle phenotype and atrophy on CaN levels in muscle, the levels of soluble CaN in rat muscles of varying phenotype, as assessed by myosin heavy chain (MHC)-isoform proportions, were determined by Western blotting. CaN levels were significantly greater in the plantaris muscle containing predominantly fast (IIx and IIb) MHC isoforms, compared with the soleus (predominantly type I MHC) or vastus intermedius (VI, contains all 4 adult MHC isoforms). Three months after a complete spinal cord transection (ST), the CaN levels in the VI muscle were significantly reduced, despite a significant increase in fast MHC isoforms. Surprisingly, the levels of CaN in the VI were highly correlated with muscle mass but not MHC isoform proportions in ST and control rats. These data demonstrate that CaN levels in skeletal muscle are highly correlated to muscle mass and that the normal relationship with phenotype is lost after ST.


Sign in / Sign up

Export Citation Format

Share Document