• Asian-Australasian Journal of Animal Sciences
• /
• v.20 no.4
• /
• pp.501-510
• /
• 2007

The present study was conducted to establish primary bovine muscle satellite cell (MSC) culture conditions and to investigate the effects of various steroid hormones on transcription of the genes involved in muscle cell proliferation and differentiation. Of three different types of proteases (type II collagenase, pronase and trypsin-EDTA) used to hydrolyze the myogenic satellite cells from muscle tissues, trypsin-EDTA treatment yielded the highest number of cells. The cells separated by hydrolysis with type II collagenase and incubated on gelatin-coated plates showed an enhanced cell attachment onto the culture plate and cell proliferation at an initial stage of cell growth. In this study, the bovine MSCs were maintained in vitro up to passage 16 without revealing any significant morphological change, and even to when the cells died at passage 21 with decreased or almost no cell growth or deformities. When the cells were incubated in a steroid-depleted environment (DMEM(-)/10% CDFBS (charcoal-dextran stripped FBS)), they grew slowly initially, and were widened and deformed. In addition, when the cells were transferred to an incubation medium containing steroid (DMEM(+)/10% FBS), the deformed cells resumed their growth and returned to a normal morphology, suggesting that steroid hormones are crucial in maintaining normal MSC morphology and growth. The results demonstrated that treatments with 19-nortestosterone and testosterone significantly increased AR gene expression (p<0.05), implying that both testosterone and 19-nortestosterone bind with AR and that the hormone bound-AR complex up-regulates the genes of its own receptor (AR) plus other genes involved in satellite cell growth and differentiation in bovine muscle.

• Journal of Animal Science and Technology
• /
• v.63 no.4
• /
• pp.673-680
• /
• 2021

The purpose of this study was to establish a basic principal procedure for the processing of cultured meat. The first stage involved isolating satellite cells from the desired muscle of an animal using enzymatic digestion (i.e., by using proteases, collagenases, and pronases). The second stage involved culturing the isolated muscle satellite cells in a growth medium containing fetal bovine serum and penicillin/streptomycin with growth factors for an optimal period of time. The second stage involved a basic method for the isolated muscle cells to proliferate while sub-culturing to further induce differentiation in gelatin-coated culture dishes with the general culture medium. The third stage involved the induction of differentiation of muscle satellite cells or formation of myotubes using myogenic medium. Lastly, the fourth stage involved the identification of cell differentiation or myotube formation (myogenesis) using fluorescent dyes. Moreover, the principle of these protocols can be applied to perform primary culture of animal cells. This study will assist beginners with the technical aspects of culturing meat (isolation, cultivation, and differentiation of muscle satellite cells as well as identification of myotube formation for myogenesis).

• Journal of Practical Agriculture & Fisheries Research
• /
• v.23 no.1
• /
• pp.117-128
• /
• 2021

The skeletal muscle development of Hanwoo steer has been processed in the prenatal and postnatal periods. Bovine satellite cell located in perimysium of muscle tissues has differentially distributed in peripheral tissues. The study of postnatal development of satellite cells can help understand the genetic and functional regulation of meat characteristics. Factors affecting muscle size increase are related to the accumulation of DNA or synthesis of RNA proteins. In this study, we observed muscle development and differentiation after culturing bovine satellite cells derived from longissimus dorsi and semimembranosus regions of Hanwoo muscle tissue. In addition, RNA sequencing data were analyzed for differentially expressed genes (DEG) involved in intracellular muscle development and growth. The DEG of the two muscle tissues were compared according to 1day, 2day, 4day, and 7day. The overall gene expression level was confirmed by the heat map. Gene Ontology (GO) classification method was used to compare the expression level of gene groups affecting LD and SM development. The histology of GO was consistent with the time-cause change of LD and SM cell morphology. SM showed more active skeletal muscle development than LD. Even within the same time, SM expressed more genes than LD, thus synthesizing more muscle fibers

• Journal of Animal Science and Technology
• /
• v.54 no.3
• /
• pp.219-226
• /
• 2012

Gender specificity in muscle growth and development is well known. Genesis of muscle is dependent on proliferation and differentiation potential of resident myogenic satellite cells (MSCs) present in muscle fibers. Multipotential capacity of forming myocyte, osteocyte, and adipocyte like cell makes MSCs a unique stem cell. To understand the molecular mechanism involved in determination of muscle quality due to difference in hormone concentration of different gender of animals, MSCs were isolated from bovine skeletal muscle and cultured in male, female, and castrated serum supplemented media. DNA microarray used consisted of 24,000 spots with 70 mer oligo in each spot. A total of 88 genes were up-regulated and 551 genes were down-regulated by more than two fold. Among up-regulated gene, 33, 34, and 21 genes were found up-regulated in cells grown in male, female, and castrated serum, respectively. Interestingly, male serum showed 4, female 11 and castrated male showed 4 genes expressed highly in each gender. Further study on the highly up-regulated gene may unfold the mystery of gender specificity found in muscle development. Also, the identification of differentially expressed genes in gender-specific serum will add information on infrastructure of bovine genome research.

• Journal of Animal Science and Technology
• /
• v.52 no.4
• /
• pp.329-336
• /
• 2010

Myogenic satellite cells (MSCs) are mononuclear, multipotent progenitors of adult skeletal muscle possessing a capacity of forming adipocyte-like cells (ALC). To identify the skeletal muscle type-specific myogenic and adipogenic genes during MSCs differentiation, total RNA was extracted from bovine MSCs, myotube-formed cell (MFC), and ALC from each of Beef shank, Longissimus dorsi, Deep pectoral, and Semitendinosus. DNA microarray analysis (24,000 oligo chip) comparing MSCs with MFC and ALC, respectively, revealed 135 differentially expressed genes (> 4 fold) among four cuts. Real-time PCR confirmed expression of 29 genes. Furthermore, the whole tissue sample RNAs analysis showed 6 differentially expressed genes in Beef shank. Among which, 1 gene in MSCs, 4 in MFC, and 1 in ALCs were highly expressed. This study will provide an insight for better understanding the molecular mechanism of differentiation of skeletal muscle type-specific MSCs. The identified genes may be used as marker to distinguish skeletal muscle types.

• Korean Journal of Agricultural Science
• /
• v.45 no.4
• /
• pp.715-723
• /
• 2018

The present study was done to investigate the effect of co-culturing muscle satellite cells (MSCs) and intramuscular preadipocytes (IPs) on the differentiation of adipocytes and muscle cells isolated from Korean native cattle. MSCs and IPs were single-cultured in 10% fetal bovine serum/Dulbecco's modified Eagles medium (FBS/DMEM) for 48 h followed by culturing in 5% FBS/DMEM as the growth media. Then, the growth media was replaced by differentiation media composed of 2% FBS/DMEM without any additives for the single- or co-culture of muscle cells and intramuscular adipocytes to induce the differentiation of both cell types. Cell differentiation was measured by morphological investigation and cytosolic enzyme analysis of glycerol-3-phosphate dehydrogenase (GPDH) for the adipocytes and creatine kinase (CK) for the muscle cells. In the morphological test, the presence of muscle cells did not stimulate adipocyte differentiation showing more differentiation of the adipocytes in the single-culture compared to the co-culture condition. However, the differentiation of muscle cells was promoted by adipocytes in the co-culture. The results of the enzymatic analysis were highly associated with the morphological results with a statistically higher GPDH activity (p < 0.05) appearing in the single-culture than in the co-culture, whereas the opposite was true for the CK activity of the muscle cells (p < 0.05). By manipulating in vivo the milieu using a co-culture, we could detect the difference in the rate of cell differentiation and suggest that a co-culture system is a more reliable and precise technique compared to a single-culture. Further studies on various co-culture trials including supplementation of differentiating substances, gene expression analysis, etc. should be done to obtain practical and fundamental data.

• Food Science of Animal Resources
• /
• v.43 no.6
• /
• pp.1017-1030
• /
• 2023

Fetal bovine serum (FBS), which contains various nutrients, comprises 20% of the growth medium for cell-cultivated meat. However, ethical, cost, and scientific issues, necesitates identification of alternatives. In this study, we investigated commercially manufactured serum-free media capable of culturing Hanwoo satellite cells (HWSCs) to identify constituent proliferation enhancing factors. Six different serum-free media were selected, and the HWSC proliferation rates in these serum-free media were compared with that of control medium supplemented with 20% FBS. Among the six media, cell proliferation rates were higher only in StemFlex^TM Medium (SF) and Mesenchymal Stem Cell Growth Medium DXF (MS) than in the control medium. SF and MS contain high fibroblast growth factor 2 (FGF2) concentrations, and we found upregulated FGF2 protein expression in cells cultured in SF or MS. Activation of the fibroblast growth factor receptor 1 (FGFR1)-mediated signaling pathway and stimulation of muscle satellite cell proliferation-related factors were confirmed by the presence of related biomarkers (FGFR1, FRS2, Raf1, ERK, p38, Pax7, and MyoD) as indicated by quantitative polymerase chain reaction, western blotting, and immunocytochemistry. Moreover, PD173074, an FGFR1 inhibitor suppressed cell proliferation in SF and MS and downregulated related biomarkers (FGFR1, FRS2, Raf1, and ERK). The promotion of cell proliferation in SF and MS was therefore attributed to FGF2, which indicates that FGFR1 activation in muscle satellite cells may be a target for improving the efficiency of cell-cultivated meat production.

• Journal of Animal Science and Technology
• /
• v.51 no.6
• /
• pp.459-470
• /
• 2009

The aim of this study was to analyze the proteome of proliferating bovine satellite cells from longissimus dorsi, deep pectoral and semitendinosus muscle depots which had been subjected to hormonal deprivation or addition in culture. For hormone deprivation or addition studies, the cells were either grown in 10% charcoal-dextran stripped fetal bovine serum (CD-FBS) or in 10% FBS supplemented medium. Further to analyze the effect of insulin like growth factor (IGF-1) and testosterone (TS), the cells were grown in 10% CD-FBS containing IGF-1 (10 ng/ml) or TS (10 nM). Results have shown that hormone deprivation had a negative impact on proliferation of the cells from each of the muscle depots. In case of IGF-1 and TS addition, the proliferation levels were low compared with that of the cells grown in 10% FBS. Hence, to gain the insights of the proteins that are involved in such divergent levels of proliferation, the proteome of such satellite cells proliferating under the above mentioned conditions were analyzed using 2D-DIGE and MALDI-ToF/ToF. Thirteen proteins during hormone deprivation and nine proteins from hormone addition were found to be differentially expressed in all the cultures of the cells from the three depots. Moreover, the results highlighted in this study offer a role for each differentially expressed protein with respect to its effect on positive or negative regulation of cell proliferation.

• Food Science of Animal Resources
• /
• v.30 no.5
• /
• pp.842-850
• /
• 2010

Sex steroids are known to be involved in skeletal muscle development (anabolic effect) and are frequently used in medicines. It has been known that pork contains a variety of steroids that are mainly synthesized in the gonads (testis and ovary). Thus, the present study was conducted to evaluate the effects of anabolic steroids of pork on the proliferation and differentiation of myogenic satellite cells (MSC). Three different methods (M1, M2, and M3) were developed for the isolation and purification of steroids from porcine tissues. Among three extraction methods that we developed, M3 was the best method with respect to the quantities of steroids and the induction of MSC proliferation. Hormonal analysis showed that the steroid hormone levels were the highest in muscle and fat of intact male than those of castrated males and females. In addition, the highest serum levels of nandrolone and testosterone were detected in intact males, whereas estrone and $17{\beta}$-estradiol levels were similar in the entire experimental serum samples. Expression of androgen receptor (AR), myoD, desmin, and myogenin in bovine muscle cells were significantly up-regulated by the treatment of steroid extracts. The highest increas of myogenin and AR mRNA abundance were observed in the MSCs treated with M3 extract (p<0.001). Altogether, the present research showed the positive effect of steroids on MSC proliferation and differentiation in vitro. These results would certainly imply a beneficial effect of pork consumption on human muscle development.

• Journal of Animal Science and Technology
• /
• v.63 no.4
• /
• pp.934-953
• /
• 2021

Ciglitazone is a member of the thiazolidinedione family, and specifically binds to peroxisome proliferator-activated receptor-γ (PPARγ), thereby promoting adipocyte differentiation. We hypothesized that ciglitazone as a PPARγ ligand in the absence of an adipocyte differentiation cocktail would increase adiponectin and adipogenic gene expression in bovine satellite cells (BSC). Muscle-derived BSCs were isolated from six, 18-month-old Yanbian Yellow Cattle. The BSC were cultured for 96 h in differentiation medium containing 5 µM ciglitazone (CL), 10 µM ciglitazone (CM), or 20 µM ciglitazone (CH). Control (CON) BSC were cultured only in a differentiation medium (containing 2% horse serum). The presence of myogenin, desmin, and paired box 7 (Pax7) proteins was confirmed in the BSC by immunofluorescence staining. The CL, CM, and CH treatments produced higher concentrations of triacylglycerol and lipid droplet accumulation in myotubes than those of the CON treatment. Ciglitazone treatments significantly increased the relative expression of PPARγ, CCAAT/enhancer-binding protein alpha (C/EBPα), C/EBPβ, fatty acid synthase, stearoyl-CoA desaturase, and perilipin 2. Ciglitazone treatments increased gene expression of Pax3 and Pax7 and decreased expression of myogenic differentiation-1, myogenin, myogenic regulatory factor-5, and myogenin-4 (p < 0.01). Adiponectin concentration caused by ciglitazone treatments was significantly greater than CON (p < 0.01). RNA sequencing showed that 281 differentially expressed genes (DEGs) were found in the treatments of ciglitazone. DEGs gene ontology (GO) analysis showed that the top 10 GO enrichment significantly changed the biological processes such as protein trimerization, negative regulation of cell proliferation, adipocytes differentiation, and cellular response to external stimulus. Kyoto Encyclopedia of Genes and Genomes pathway analysis showed that DEGs were involved in the p53 signaling pathway, PPAR signaling pathway, biosynthesis of amino acids, tumor necrosis factor signaling pathway, non-alcoholic fatty liver disease, PI3K-Akt signaling pathway, and Wnt signaling pathway. These results indicate that ciglitazone acts as PPARγ agonist, effectively increases the adiponectin concentration and adipogenic gene expression, and stimulates the conversion of BSC to adipocyte-like cells in the absence of adipocyte differentiation cocktail.