• Proceedings of the Ginseng society Conference
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• 1993.09a
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• pp.127-131
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• 1993

The effects of total ginseng saponin. extracts of Panax ginseng C.A. Meyer, on the differentiation of F9 teratocarcinoma stem cells were studied. F9 stem cells cultured in the presence of ginseng saponin together with dibutyric cAMP became parietal endoderm - like cells. Moreover, the expressions of differentiation marker genes. laminin. type IV collagen. and retinoic acid $receptor-{\beta}(RAR{\beta})$ were increased after treatment of ginseng saponin. Among various ginsenosides purified from crude ginseng saponin, $Rh_1\;and\;Rh_2$ caused the differentiation of F9 cells most effectively. Since ginsenosides and steroid hormone show resemblance in chemical structure. we studied the possibility of the involvement of a steroid receptor in the differentiation process induced by ginsenosides. According to Southwestern blot analysis, a 94 kDa protein regarding as a steroid receptor was detected in F9 cells cultured in the medium containing ginseng saponin. Based on these data, we suggest that ginseng saponin, especially ginsenosides $Rh_1\;and\;Rh_2$ cause the differentiation of F9 cells and the effects of ginsenosides might be exerted via binding with a steroid receptor or its analogous nuclear receptor.

• Proceedings of the Korean Society of Toxicology Conference
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• 2005.05a
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• pp.51-82
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• 2005

To compare the pulmonary toxicity between ultrafine colloidal silica particles (UFCSs) and fine colloidal silica particles (FCSs), mice were intratracheally instilled with 3 mg of 14-nm UFCSs and 230-nm FCSs and pathologically examined from 30 mill to 24 hr post-exposure. Histopathologically, lungs exposed to both sizes of particles showed bronchiolar degeneration and necrosis, neutrophilic inflammation in alveoli with alveolar type II cell proliferation and particle-laden alveolar macrophage accumulation. UFCSs, however, induced extensive alveolar hemorrhage compared to FCSs from 30 min onwards. UFCSs also caused more severe bronchiolar epithelial cell necrosis and neutrophil influx in alveoli than FCSs at 12 and 24 hr post-exposure. Laminin positive immunolabellings in basement membranes of bronchioles and alveoli of UFCSs treated animals was weaker than those of FCSs treated animals in all observation times. Electron microscopy demonstrated UFCSs and FCSs on bronchiolar and alveolar wall surface as well as in the cytoplasm of alveolar epithelial cells, alveolar macrophages and neutrophils. Type I alveolar epithelial cell erosion with basement membrane damage in UFCSs treated animals was more severe than those in FCSs treated animals. At 12 and 24 hr post-exposure, bronchiolar epithelia cells in UFCSs treated animals showed more intense vacuolation and necrosis compared to FCSs treated animals. These findings suggest that UFCSs has greater ability to induce lung inflammation and tissue damages than FCSs.

• Biomolecules & Therapeutics
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• v.27 no.2
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• pp.185-192
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• 2019

Coculture with adipose-derived stem cells (ADSCs) can stimulate proliferation and migration of melanocytes. To enhance outcomes of skin disorders caused by melanocyte loss or death, mixed transplantation with ADSCs has been suggested. However, role of cocultured ADSCs in proliferation and migration of melanocytes remains unclear. This study determined the effect of ADSCs on production of growth factors and expression levels of intergrins in primary culture of adult human melanocytes with or without ADSCs and in nude mice grafted with such melanocytes. Higher amounts of growth factors for melanocytes, such as bFGF and SCF were produced and released from ADSCs by coculturing with melanocytes. Relative levels of integrins ${\beta}1$, ${\alpha}5$, and ${\alpha}6$ as well as adhesion to fibronectin and laminin were increased in melanocytes cocultured with ADSCs. Such increases were inhibited by neutralization of bFGF or SCF. Relative levels of bFGF, SCF and integrins were increased in nude mice skin after grafting with melanocyte+ADSC cocultures. Collectively, these results indicate that ADSCs can stimulate proliferation and migration of melanocytes by increasing expression of integrins in melanocytes through upregulation of production/release of melanocyte growth factors such as bFGF and SCF.

• Journal of Microbiology and Biotechnology
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• v.31 no.8
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• pp.1175-1182
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• 2021

We investigated the effect of bovine lactoferricin (Lfcin-B), a peptide derived from bovine lactoferrin, on activation of intestinal epithelial cells in IEC-6 intestinal cell, and protection against in vivo rotavirus (RV) infection. Treatment with Lfcin-B significantly enhanced the growth of IEC-6 cells and increased their capacity for attachment and spreading in culture plates. Also, Lfcin-B synergistically augmented the binding of IEC-6 cells to laminin, a component of the extracellular matrix (ECM). In the analysis of the intracellular mechanism related to Lfcin-B-induced activation of IEC-6 cells, this peptide upregulated tyrosine-dependent phosphorylation of focal adhesion kinase (FAK) and paxillin, which are intracellular proteins associated with cell adhesion, spreading, and signal transduction during cell activation. An experiment using synthetic peptides with various sequences of amino acids revealed that a sequence of 9 amino acids (FKCRRWQWR) corresponding to 17-25 of the N-terminus of Lfcin-B is responsible for the epithelial cell activation. In an in vivo experiment, treatment with Lfcin-B one day before RV infection effectively prevented RV-induced diarrhea and significantly reduced RV titers in the bowels of infected mice. These results suggest that Lfcin-B plays meaningful roles in the maintenance and repair of intestinal mucosal tissues, as well as in protecting against intestinal infection by RV. Collectively, Lfcin-B is a promising candidate with potential applications in drugs or functional foods beneficial for intestinal health and mucosal immunity.

• BMB Reports
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• v.56 no.2
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• pp.126-131
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• 2023

The abnormal accumulation and aggregation of the misfolded α-synuclein protein is the neuropathological hallmark of all α-synucleinopathies, including Parkinson's disease. The secreted proteins known as netrins (netrin-1, netrin-3, and netrin-4) are related to laminin and have a role in the molecular pathway for axon guidance and cell survival. Interestingly, only netrin-1 is significantly expressed in the substantia nigra (SN) of healthy adult brains and its expression inversely correlates with that of α-synuclein, which prompted us to look into the role of α-synuclein and netrin-1 molecular interaction in the future of dopaminergic neurons. Here, we showed that netrin-1 and α-synuclein directly interacted in pre-formed fibrils (PFFs) generation test, real time binding assay, and co-immunoprecipitation with neurotoxin treated cell lysates. Netrin-1 deficiency appeared to activate the dopaminergic neuronal cell death signal pathway via α-synuclein aggregation and hyperphosphorylation of α-synuclein S129. Taken together, netrin-1 can be a promising therapeutic molecule in Parkinson's disease.

• BMB Reports
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• v.45 no.3
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• pp.159-164
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• 2012

CD99 is known to be involved in the regulation of cell-cell adhesion. However, it remains unclear whether CD99 controls cell-extracellular matrix adhesion. In this study, the effects of CD99 activation on cell-extracellular matrix adhesion were investigated. It was found that engagement of CD99 with the stimulating antibody YG32 downregulated the adhesion of MCF-7 cells to fibronectin, laminin and collagen IV in a dose-dependent manner. The CD99 effect on cell-ECM adhesion was inhibited by overexpression of the dominant negative form of CD99 or CD99 siRNA transfection. Treatment of cells with $Mn^{2+}$ or by ${\beta}_1$ integrin-stimulating antibody restored the inhibitory effect of CD99 on cell-ECM adhesion. Cross-linking CD99 inactivated ${\beta}_1$ integrin through conformational change. CD99 activation caused dephosphorylation at Tyr-397 in FAK, which was restored by the ${\beta}_1$ stimulating antibody. Taken together, these results provide the first evidence that CD99 inhibits cell-extracellular matrix adhesion by suppressing ${\beta}_1$ integrin affinity.

• Biomolecules & Therapeutics
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• v.24 no.3
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• pp.260-267
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• 2016

Mesenchymal stem cells (MSCs) offer significant therapeutic promise for various regenerative therapies. However, MSC-based therapy for injury exhibits low efficacy due to the pathological environment in target tissues and the differences between in vitro and in vivo conditions. To address this issue, we developed adipose-derived MSC spheroids as a novel delivery method to preserve the stem cell microenvironment. MSC spheroids were generated by suspension culture for 3 days, and their sizes increased in a time-dependent manner. After re-attachment of MSC spheroids to the plastic dish, their adhesion capacity and morphology were not altered. MSC spheroids showed enhanced production of hypoxia-induced angiogenic cytokines such as vascular endothelial growth factor (VEGF), stromal cell derived factor (SDF), and hepatocyte growth factor (HGF). In addition, spheroid culture promoted the preservation of extracellular matrix (ECM) components, such as laminin and fibronectin, in a culture time- and spheroid size-dependent manner. Furthermore, phosphorylation of AKT, a cell survival signal, was significantly higher and the expression of pro-apoptotic molecules, poly (ADP ribose) polymerase-1 (PARP-1) and cleaved caspase-3, was markedly lower in the spheroids than in MSCs in monolayers. In the murine hindlimb ischemia model, transplanted MSC spheroids showed better proliferation than MSCs in monolayer. These findings suggest that MSC spheroids promote MSC bioactivities via secretion of angiogenic cytokines, preservation of ECM components, and regulation of apoptotic signals. Therefore, MSC spheroid-based cell therapy may serve as a simple and effective strategy for regenerative medicine.

• Proceedings of the SCSK Conference
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• 2003.09a
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• pp.352-373
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• 2003

Rhamnose-rich (RROP-s) and fucose-rich (FROP-s) oligo-and polysaccharides were prepared and extensively characterised by physical and chemical procedures [1,2] and compared to L-fucose. Their biological properties were then studied on human skin fibroblast cell cultures, human skin explant cultures and on hairless rat skin, using a variety of cell-biological, biochemical and computerised morphometrical procedures. Among the most important properties we could establish, the following are of particular interest for the tretment and prevention of age-dependent modifications of human skin (loss of skin-tissue, cells and matrix, wrinkle formation and others) : stimulation of cell proliferation (by $^3$[H]-thymidine incorporation and the MTT test), scavenging of reactive oxygen species (ROS) using several different procedures, and protease (MMP-2 and MMP-9) down-regulation. A topical preparation, using RROP-s and FROP-s, and/or L-fucose, was shown to increase cell proliferation, dermal matrix synthesis, efficient scavenging of ROS-s and to increase also the thickness of dermal tissue when applied for 4 weeks on hairless rat skin, accompanied by the densification of collagen bundles as well as by an increase of elastin synthesis. Using fluorescent labeled FROPs, it could be shown that these oligosaccharides react with cell-membrane receptors and especially with the elastin-laminin-receptor and the fucose-mannose receptor, but they penetrate also in the cell nucleus, suggesting the possibility of a direct action on the regulation of gene expression. When applied to the human skin of a team of voluntary women encompassing all age-groups, the efficiency of FROP-containing preparation could be confirmed using indentometry and computerised evaluation of skin micro-relief, as well as evaluation of periorbital wrinkles. It appears therefore that these preparations correspond to all the requirements of active anti-aging principles.

• Proceedings of the Korean Society of Embryo Transfer Conference
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• 2002.11a
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• pp.63-65
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• 2002

Identification of spermatogonial stem cell-specific surface molecules is important in understanding the molecular mechanisms underlying the maintenance and differentiation of these cells. We have found that spermatogonia from busulfan treated mice expressed an autoantigen that distinguishes between undifferentiated and differentiated spermatogonia. Four to six weeks after busulfan treatment, germ cells located in the basal compartment of seminiferous epithelium show isotype-specific IgG deposits that form due to autoimmunity. Before busulfan treatment, the level of testicular IgG was very low but IgG levels began to increase after week 4 and peaked at week 6. When cells from the busulfan treated testis were analyzed using laser scanning cytomeoy (LSC), the frequency of cells positive for IgG deposits, 6-integrin, and 1-integrin were 16.5${\pm}$3.8%, 11.8${\pm}$2.6%, and 9.0${\pm}$ 1.4%, respectively. Immunofluorescent staining suggested that most, if not all of the cells with IgG-deposits isolated from a laminin-coated dish, were also positive for a spermatogonial stem cell marker \ulcorner6-integrins as well as for a germ cell-specific marker TRA 98. We determined serum and intratesticular IgG levels and the soundness of seminiferous tubule basement membrane from busulfan treated mice using electron microscopy, in order to study the mechanism responsible for IgG deposits in spermatogonia. We found that the basement membranes of seminiferous tubules from busulfan treated mice were severely impaired when compared to those of normal adult, neonates and w/wv mice. Furthermore, new blood cells were observed in the surface of the damaged basement membrane along the seminiferous tubules. These results suggest that the IgG in spermatogonial stem cells accumulates from circulating blood through the impaired basement membranes induced by busulfan treatment. Taken together, our study suggests that IgG can be used as a new marker for undifferentiated spermatogonia cells.

• Tuberculosis and Respiratory Diseases
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• v.41 no.1
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• pp.36-41
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• 1994

Angiosarcoma is a very rare malignant tumor of endothelial cell origin. We experienced a case of angiosarcoma presented with massive pleural effusion, which was considered as a metastasis from right kidney. A 44-year-old male patient was admitted due to dyspnea for one month. He had a history of transient hematuria 3 months before admission, which disappeared spontaneously. Chest roentgenography showed total haziness in left hemithorax with multiple nodular shadows in right lung. Abdominal ultrasonogram showed a single heterogeneous hyperechoic mass, measuring about $7.3{\times}7.1{\times}6.5cm$ in size in the upper and mid-pole of the right kidney, involving renal sinus. Computed tomography of the chest revealed highly enhanced multiple pulmonary and subpleural nodules with loculated pleurisy. In bronchoscopic finding, a fungating, hypervascular tumor mass was noticed at the orifice of anterior basal segment of left lower lung after removal of tenaceous mucus. Pleural and bronchoscopic biopsies showed findings of angiosarcoma confirmed by immunochemical stains with factor VIII related antigen(+), laminin(+) and vimentin(+), and by characteristic electronmicroscopic findings. Massive pleural effusion was controlled with several times of pleurodesis in both pleural spaces.