• Endocrinology and Metabolism
• /
• v.37 no.3
• /
• pp.408-414
• /
• 2022

Skeletal muscle is now regarded as an endocrine organ based on its secretion of myokines and exerkines, which, in response to metabolic stimuli, regulate the crosstalk between the skeletal muscle and other metabolic organs in terms of systemic energy homeostasis. This conceptual basis of skeletal muscle as a metabolically active organ has provided insights into the potential role of physical inactivity and conditions altering muscle quality and quantity in the development of multiple metabolic disorders, including insulin resistance, obesity, and diabetes. Therefore, it is important to understand human muscle physiology more deeply in relation to the pathophysiology of metabolic diseases. Since monolayer cell lines or animal models used in conventional research differ from the pathophysiological features of the human body, there is increasing need for more physiologically relevant in vitro models of human skeletal muscle. Here, we introduce recent studies on in vitro models of human skeletal muscle generated from adult myogenic progenitors or pluripotent stem cells and summarize recent progress in the development of three-dimensional (3D) bioartificial muscle, which mimics the physiological complexity of native skeletal muscle tissue in terms of maturation and functionality. We then discuss the future of skeletal muscle 3D-organoid culture technology in the field of metabolic research for studying pathological mechanisms and developing personalized therapeutic strategies.

• Journal of Embryo Transfer
• /
• v.29 no.1
• /
• pp.91-99
• /
• 2014

Oxygen consumption is a useful parameter for evaluating mammalian embryo quality, since individual bovine embryos was noninvasively quantified by scanning electrochemical microscopy (SECM). Recently, several approaches have been used to measure the oxygen consumption rates of individual embryos, but relationship between oxygen consumption and pregnancy rates of Hanwoo following embryo transfer has not yet been reported. In this study, we measured to investigate the correlation between oxygen consumption rate and pregnancy rates of Hanwoo embryo using a SECM. In addition to, the expression of pluripotent gene and anti-oxidant enzyme was determined using real-time PCR by extracting RNA according to the oxygen consumption of in vivo embryo. First, we found that the oxygen consumption significantly increased in blastocyst-stage embryos (blastocyst) compared to early blastocyst stage embryos, indicating that oxygen consumption reflects the embryo quality (Grade I). Oxygen consumption of blastocyst was measured using a SECM and total cell number of in vitro blastocyst was enumerated by counting cells stained by propidium iodide. The oxygen consumption or GI blastocysts were significantly higher than those of GII blastocysts ($10.2{\times}10^{15}/mols^{-1}$ versus $6.4{\times}10^{15}/mols^{-1}$, p<0.05). Total cell numbers of in vitro blastocysts were 74.8, 90.7 and 110.2 in the oxygen consumption of below 10.0, 10.0~12.0 and over $12.0{\sim}10^{15}/mols^{-1}$, respectively. Pregnant rate in recipient cow was 0, 60 and 80% in the transplantation of embryo with the oxygen consumption of below 10.0, 10.0~12.0 and over $12.0{\times}10^{15}/mols^{-1}$, respectively. GPX1 and SOD1 were significantly increased in over -10.0 group than below 10.0 groups but in catalase gene, there was no significant difference. On the other hand, In OCT-4 and Sox2, pluripotent gene, there was a significant difference (p<0.05) between the below-10.0 ($0.98{\pm}0.1$) and over 10.0 ($1.79{\pm}0.2$). In conclusion, these results suggest that measurement of oxygen consumption maybe help increase the pregnant rate of Hanwoo embryos.

• Asian-Australasian Journal of Animal Sciences
• /
• v.22 no.1
• /
• pp.26-34
• /
• 2009

Porcine embryonic stem (ES) cells have a great potential as tools for transgenic animal production and studies of regulation of differentiation genes. Although several studies showed successful derivation of porcine ES-like cells, these cells were not maintained long-term in culture. Therefore, this study was conducted to establish porcine pluripotent ES-like cells using in vivo fertilized embryos and to maintain these cells in long term culture. Porcine ES-like cells from in vivo embryos obtained by immunosurgery or whole explant culture were successfully cultured for over 56 passages. Morphology of porcine ES-like cells was flat-shaped with a monolayer type colony. These cells stained for alkaline phosphatase throughout the culture. Furthermore, porcine ES-like cells reacted with antibodies against Oct-4, SSEA-1, SSEA-4, Tra-1-60, and Tra-1-81, which are typical markers of undifferentiated stem cells. To characterize the ability of porcine ES-like cells to differentiate into three germ layers, embryoid body formation was induced. After plating of these cells, porcine ES-like cells were spontaneously differentiated into various cell types of all three germ layers. In addition, porcine ES-like cells were successfully derived from IVF blastocysts in media containing human recombinant basic fibroblast growth factor.

• BMB Reports
• /
• v.48 no.2
• /
• pp.68-80
• /
• 2015

G protein-coupled receptors (GPCRs) are a large class of transmembrane receptors categorized into five distinct families: rhodopsin, secretin, adhesion, glutamate, and frizzled. They bind and regulate 80% of all hormones and account for 20-50% of the pharmaceuticals currently on the market. Hundreds of GPCRs integrate and coordinate the functions of individual cells, mediating signaling between various organs. GPCRs are crucial players in tumor progression, adipogenesis, and inflammation. Several studies have also confirmed their central roles in embryonic development and stem cell maintenance. Recently, GPCRs have emerged as key players in the regulation of cell survival, proliferation, migration, and self-renewal in pluripotent (PSCs) and cancer stem cells (CSCs). Our study and other reports have revealed that the expression of many GPCRs is modulated during the generation of induced PSCs (iPSCs) or CSCs as well as during CSC sphere formation. These GPCRs may have crucial roles in the regulation of self-renewal and other biological properties of iPSCs and CSCs. This review addresses the current understanding of the role of GPCRs in stem cell maintenance and somatic reprogramming to PSCs or CSCs.

• BMB Reports
• /
• v.45 no.12
• /
• pp.713-718
• /
• 2012

Gangliosides play important roles in the control of several biological processes, including proliferation and transmembrane signaling. In this study, we demonstrate the effect of ganglioside GM1 on the proliferation of mouse induced pluripotent stem cells (miPSCs). The proliferation rate of miPSCs was lower than in mouse embryonic stem cells (mESCs). Fluorescence activated cell sorting analysis showed that the percentage of cells in the G2/M phase in miPSCs was lower than that in mESCs. GM1 was expressed in mESCs, but not miPSCs. To confirm the role of GM1 in miPSC proliferation, miPSCs were treated with GM1. GM1-treated miPSCs exhibited increased cell proliferation and a larger number of cells in the G2/M phase. Furthermore, phosphorylation of mitogen-activated protein kinases was increased in GM1-treated miPSCs.

• Biomolecules & Therapeutics
• /
• v.27 no.1
• /
• pp.15-24
• /
• 2019

Neural stem cells (NSCs) can proliferate and differentiate into multiple cell types that constitute the nervous system. NSCs can be derived from developing fetuses, embryonic stem cells, or induced pluripotent stem cells. NSCs provide a good platform to screen drugs for neurodegenerative diseases and also have potential applications in regenerative medicine. Natural products have long been used as compounds to develop new drugs. In this review, natural products that control NSC fate and induce their differentiation into neurons or glia are discussed. These phytochemicals enable promising advances to be made in the treatment of neurodegenerative diseases.

• Radiation Oncology Journal
• /
• v.9 no.1
• /
• pp.117-122
• /
• 1991

Malignant small round cell tumor (SRCT) of the thoracopulmonary region appears to originate in the soft tissues of the chest wall or the peripheral lung. A differential diagnosis of poorly differentiated small round cell tumors which include Ewing's sarcoma of bone and soft tissue, embryonal rhabdomyosarcoma, Askin tumor, neuroblastoma, peripheral neuroectodermal tumor, small cell osteogenic sarcoma and Iymphoma are often difficult by light microscopy alone. In recent, by the extensive studies electron microscopic examination, histochemical study, immune-chemical study, cytogenetics and gene analysis, these tumors may be derived from the primitive and pluripotential cells, differentiating into mesenchymal, epithelial and neural features in variable proportions. Treatment for SRCT of thoracopulmonary region is not determined because of massive involvement of the lung, pleura or soft tissues of the chest wall resulted in a dismal outcome despite aggressive surgery, irradiation and chemotherapy.

• Development and Reproduction
• /
• v.14 no.2
• /
• pp.43-50
• /
• 2010

Recently induced pluripotent stem (iPS) cells are derived from somatic cells by ectopic expression of several transcription factors (reprogramming factors) using technology of somatic cell reprogramming. iPS cells are able to selfrenew and differentiate into all type of cells in the body similarly to embryonic stem cells. Because iPS cells have advantages that can avoid immune rejection after transplantation and ethical issues unlike embryonic stem cells, research on iPS has made significant progress since the first report by Yamanaka in 2006. Nevertheless of many advantages of iPS, safer methods to introduce reprogramming factors into somatic cells must be developed due to safety concerns regarding viral vectors, and safer reprogramming factors to substitute the oncogenes should be evaluated for clinical application of iPS. Here we discuss the recent progress in reprogramming factors in embryonic stem cells, oocytes, and embryos, and discuss further research for finding new, more reliable and safer reprogramming factors.

• Asian-Australasian Journal of Animal Sciences
• /
• v.28 no.11
• /
• pp.1565-1572
• /
• 2015

Porcine embryonic stem cells (pESCs) have become an advantageous experimental tool for developing therapeutic applications and producing transgenic animals. However, despite numerous reports of putative pESC lines, deriving validated pESC lines from embryos produced in vitro remains difficult. Here, we report that embryo aggregation was useful for deriving pESCs from in vitro-produced embryos. Blastocysts derived from embryo aggregation formed a larger number of colonies and maintained cell culture stability. Our derived cell lines demonstrated expression of pluripotent markers (alkaline phosphatase, Oct4, Sox2, and Nanog), an ability to form embryoid bodies, and the capacity to differentiate into the three germ layers. A cytogenetic analysis of these cells revealed that all lines derived from aggregated blastocysts had normal female and male karyotypes. These results demonstrate that embryo aggregation could be a useful technique to improve the efficiency of deriving ESCs from in vitro-fertilized pig embryos, studying early development, and deriving pluripotent ESCs in vitro in other mammals.

• BMB Reports
• /
• v.51 no.2
• /
• pp.85-91
• /
• 2018

Pluripotent stem cell (PSC) variations can cause significant differences in the efficiency of cardiac differentiation. This process is unpredictable, as there is not an adequate indicator at the undifferentiated stage of the PSCs. We compared global gene expression profiles of two PSCs showing significant differences in cardiac differentiation potential. We identified 12 up-regulated genes related to heart development, and we found that 4 genes interacted with multiple genes. Among these genes, Gata6 is the only gene that was significantly induced at the early stage of differentiation of PSCs to cardiomyocytes. Gata6 knock-down in PSCs decreased the efficiency of cardiomyocyte production. In addition, we analyzed 6 mESC lines and 3 iPSC lines and confirmed that a positive correlation exists between Gata6 levels and efficiency of differentiation into cardiomyocytes. In conclusion, Gata6 could be utilized as a biomarker to select the best PSC lines to produce PSC-derived cardiomyocytes for therapeutic purposes.