• Proceedings of the Korean Society of Developmental Biology Conference
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• 2005.10a
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• pp.62-63
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• 2005

• Proceedings of the Korean Society of Embryo Transfer Conference
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• 2005.10a
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• pp.62-63
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• 2005

• 대한생식의학회:학술대회논문집
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• 2005.11a
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• pp.139-139
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• 2005

• Journal of Korean Neurosurgical Society
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• v.59 no.2
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• pp.106-116
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• 2016

Objective : Protein disulfide isomerase (PDI) acts as a chaperone on the cell surface, and it has been reported that PDI is associated with the tumor cell migration and invasion. The aims of this study are to investigate the anti-migration effect of bacitracin, which is an inhibitor of PDI, and the associated factor in this process. Methods : U87-MG glioma cells were treated with bacitracin in 1.25, 2.5, 3.75, and 5.0 mM concentrations. Western blot with caspase-3 was applied to evaluate the cytotoxicity of bacitracin. Adhesion, morphology, migration assays, and organotypic brain-slice culture were performed to evaluate the effect of bacitracin to the tumor cell. Western blot, PCR, and gelatin zymography were performed to investigate the associated factors. Thirty glioma tissues were collected following immunohistochemistry and Western blot. Results : Bacitracin showed a cytotoxicity in 3rd (p<0.05) and 4th (p<0.001) days, in 5.0 Mm concentration. The cell adhesion significantly decreased and the cells became a round shape after treated with bacitracin. The migration ability, the expression of phosphorylated focal adhesion kinase (p-FAK) and matrix metalloproteinase-2 (MMP-2) decreased in a bacitracin dose- and time-dependent manner. The U87-MG cells exhibited low-invasiveness in the 2.5 mM, compared with the untreated in organotypic brain-slice culture. PDI was expressed in the tumor margin, and significantly increased with histological glioma grades (p<0.001). Conclusion : Bacitracin, as a functional inhibitor of PDI, decreased the phosphorylated FAK and the secreted MMP-2, which are the downstream of integrin and play a major role in cell migration and invasion, might become one of the feasible therapeutic strategies for glioblastoma.

• Molecules and Cells
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• v.43 no.7
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• pp.600-606
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• 2020

Numerous physiological processes in nature have multiple oscillations within 24 h, that is, ultradian rhythms. Compared to the circadian rhythm, which has a period of approximately one day, these short oscillations range from seconds to hours, and the mechanisms underlying ultradian rhythms remain largely unknown. This review aims to explore and emphasize the implications of ultradian rhythms and their underlying regulations. Reproduction and developmental processes show ultradian rhythms, and these physiological systems can be regulated by short biological rhythms. Specifically, we recently uncovered synchronized calcium oscillations in the organotypic culture of hypothalamic arcuate nucleus (ARN) kisspeptin neurons that regulate reproduction. Synchronized calcium oscillations were dependent on voltage-gated ion channel-mediated action potentials and were repressed by chemogenetic inhibition, suggesting that the network within the ARN and between the kisspeptin population mediates the oscillation. This minireview describes that ultradian rhythms are a general theme that underlies biological features, with special reference to calcium oscillations in the hypothalamic ARN from a developmental perspective. We expect that more attention to these oscillations might provide insight into physiological or developmental mechanisms, since many oscillatory features in nature still remain to be explored.

• The Journal of Internal Korean Medicine
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• v.25 no.4
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• pp.227-241
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• 2004

Objective : This study was performed to investigate neuroprotective effects of Bupleuri Radix against oxidative and ischemic damages. Method : To observe the neuroprotective effects against ischemic damage, ischemic insult was induced by oxygen/glucose deprivation (OGD) on organotypic hippocampal slice cultures (OHSC) from 1 week-old Sprague-Dawley rats. Propidium iodide (PI) fluorescence-stained neuronal dead-cell areas, area percentages and TUNEL-positive apoptotic cells in CA1 and dentate gyrus, and LDH levels in culture media of the OHSC were measured following Bupleuri Radix extract treatment. Result : The following results were obtained: (1) The $5\;{\mu}g/ml$ of Bupleuri Radix treatment demonstrated a significant decrease in PI fluorescence-stained neuronal dead-cell areas and area percentage in CA1 region of the OHSC from 18 hrs to 48 hrs following the OGD. The $50\;{\mu}g/ml$ of Bupleuri Radix treatment was also significant from 6 hrs to 48 hrs following the OGD and was more effective. (2) The 5 and $50\;{\mu}g/ml$ of Bupleuri Radix treatment demonstrated a significant decrease in PI fluorescence-stained neuronal dead-cell areas and area percentage in DG region of the OHSC from 6 hrs to 48 hrs following the OGD. The $50\;{\mu}g/ml$ treatment was more effective than the $5\;{\mu}g/ml$ treatment. (3) Bupleuri Radix treatment demonstrated a significant decrease in TUNEL-positive apoptotic cells in CA1 region (with 5 and $50\;{\mu}g/ml$) and in DG region (with $50\;{\mu}g/ml$) of the OHSC damaged by the OGD. (4) Bupleuri Radix treatment demonstrated a significant decrease in LDH concentrations in culture media of the OHSC damaged by the OGD. Conclusion : These results suggest that Bupleuri Radix has neuroprotective and control effects on inflammatory and immune responses where there has been ischemic damage to the central nervous system.

• Biotechnology and Bioprocess Engineering:BBE
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• v.3 no.1
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• pp.1-5
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• 1998

One cervical cancer cell line, C9, carrying human papillomavirus type 18 (HPV18) genes that is one of the major etiologic concoviruses for cervical cancer was characterized. This cell line was further characterized for its capacity related to the epithelial cell proliferation, stratification and differentiation in reconstituted artificial epithelial tissue. The in vitro construction of three dimensional artificial cervical opithelial tissue has been engineered using C9 epithelial cancer cells, human foreskin fibroblasts and a matrix made of type I collagen by organotypic culture of epithelial cells. The morphology of paraffin embedded artificial tissue was examined by histochemical staining. The artificial epithelial tissues were well developed having multilayer. However, the tissue morphology was similar to the cervical tissus having displasia induced by HPV infection. The characteristics of the artificial tissues were examined by determinining the expression of specific marker proteins. In the C9 derived artificial tissues, the expression of EGF receptor, as epithelial proliferation marker proteins for stratum basale was observed up to the stratum spinosum. Another epithelial proliferation marker for stratum spinosum, cytokerations 5/6/18, were observed well over the stratum spinosum. For the differentiation markers, the expression of involucrin and filaggrin were observed while the terminal differentiation marker, cytokeratins 10/13 was not detected at all. Therefore the reconstituted artificial epithelial tissues expressed the same types of differentiation marker proteins that are expressed in normal human cervical epithelial tissues but lacked the final differentiation capacity representing characteristics of C9 cell line as a cancer tissue devived cell line. Expression of HPV18 E6 oncoprotein was also observed in this artifical cervical opithelial tissue though the intensity of the staining was weak. Thus this artificial epithelial tissue could be used as a useful model system to examine the relationship between HPV-induced cervical oncogenesis and epithelial cell differentiation.

• Journal of Life Science
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• v.28 no.6
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• pp.681-687
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• 2018

Recently, several researchers have been developing cosmetics from natural ingredients for skin whitening and anti-aging products. The red sea cucumber (RSC), Apostichopus japonicas, is a species of sea cucumber in the family stichopodiae, which is widely distributed in China, Japan, and Korea. To use Red Sea Cucumber as a cosmetic ingredient, its inhibitory effects on melanogenesis and the anti-aging effects of RSC extracts were investigated. First, a tyrosinase activity assay was performed, which showed that RSC inhibited tyrosinase activity at a concentration of $200{\mu}g/ml$. An MTT assay was carried out to evaluate cell toxicity, and the results showed that RSC extract has no cytotoxicity in HaCaT cells. Furthermore, the mRNA expression levels of tyrosinase, tyrosinase related protein 1 (TRP-1), tyrosinase related protein 2 (TRP-2), microphthalmia-associated transcription factor (MITF), and matrix metalloproteinase (MMPs) genes treated with RSC extract in B16F10 and HaCaT cells decreased. Moreover, a wound-healing assay was performed to identify the cell regeneration effect of RSC extracts. Also, a skin turnover effect was confirmed by creating a three-dimensional cell culture with HaCaT and human fibroblasts. Altogether, the results suggested that Red Sea Cucumber may possess a high ability to induce whitening and anti-wrinkle effects as a cosmeceutical ingredient.

• Journal of Periodontal and Implant Science
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• v.46 no.6
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• pp.362-371
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• 2016

Purpose: The increasing demand for esthetically pleasing results has contributed to the use of ceramics for dental implant abutments. The aim of this study was to compare the biological response of epithelial tissue cultivated on lithium disilicate ($LS_2$) and zirconium oxide ($ZrO_2$) ceramics. Understanding the relevant physicochemical and mechanical properties of these ceramics will help identify the optimal material for facilitating gingival wound closure. Methods: Both biomaterials were prepared with 2 different surface treatments: raw and polished. Their physicochemical characteristics were analyzed by contact angle measurements, scanning white-light interferometry, and scanning electron microscopy. An organotypic culture was then performed using a chicken epithelium model to simulate peri-implant soft tissue. We measured the contact angle, hydrophobicity, and roughness of the materials as well as the tissue behavior at their surfaces (cell migration and cell adhesion). Results: The best cell migration was observed on $ZrO_2$ ceramic. Cell adhesion was also drastically lower on the polished $ZrO_2$ ceramic than on both the raw and polished $LS_2$. Evaluating various surface topographies of $LS_2$ showed that increasing surface roughness improved cell adhesion, leading to an increase of up to 13%. Conclusions: Our results demonstrate that a biomaterial, here $LS_2$, can be modified using simple surface changes in order to finely modulate soft tissue adhesion. Strong adhesion at the abutment associated with weak migration assists in gingival wound healing. On the same material, polishing can reduce cell adhesion without drastically modifying cell migration. A comparison of $LS_2$ and $ZrO_2$ ceramic showed that $LS_2$ was more conducive to creating varying tissue reactions. Our results can help dental surgeons to choose, especially for esthetic implant abutments, the most appropriate biomaterial as well as the most appropriate surface treatment to use in accordance with specific clinical dental applications.

• Journal of Physiology & Pathology in Korean Medicine
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• v.19 no.3
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• pp.647-655
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• 2005

This study demonstrated anti-oxidative and neuroprotective effects of Rhei Rhizoma. Anti-oxidative effects were studied on BV-2 microglia cells damaged by $H_2O_2$ and nitric oxide. Neuroprotective effects were studied by using oxygen/glucose deprivation of the organotypic hippocampal slice cultures. The results obtained are as follows; The groups treated with 0.5 and 5 mg/ml of Puerariae Radix revealed significant decreases of neuronal cell death area and cell death area percentages in CA1 region of ischemic damaged hippocampus cultures during whole 48 hours of the experiment. The group treated with 50 mg/ml of Puerariae Radix demonstrated decreases of neuronal cell death area and cell death area percentages in CA1 region, but these were not significant statistically. The groups treated with 0.5 and 5 mg/ml of Puerariae Radix revealed significant decreases of neuronal cell death area and cell death area percentages in dentate gyrus of ischemic damaged hippocampus cultures during whole 48 hours of the experiment. The group treated with 50 mg/ml of Puerariae Radix demonstrated decreases of neuronal cell death area and cell death area percentages in dentate gyrus, but these were not significant statistically. The groups treated with 0.5 and 5 mg/ml of Puerariae Radix revealed significant decreases of TUNEL-positive cells in both CA1 region and dentate gyrus of ischemic damaged hippocampus cultures. The group treated with 50 mg/ml of Puerariae Radix demonstrated significant decrease of TUNEL-positive cells in CA1 region, but not in dentate gyrus of ischemic damaged hippocampus. The groups treated with 0.5 and 5 mg/ml of Puerariae Radix revealed significant decreases of LDH concentrations in culture media of ischemic damaged hippocampus cultures. The group treated with 50 mg/ml of Puerariae Radix demonstrated decrease of LDH concentrations in culture media, but it was not significant statistically. The groups treated with 0.5 and 5 mg/ml of Puerariae Radix revealed significant increases of cell viabilities of BV-2 microglia cells damaged by $H_2O_2$. The group treated with 50 mg/ml of Puerariae Radix demonstrated increase of cell viability of BV-2 microglia cells, but it was not significant statistically. The group treated with 0.5 mg/ml of Puerariae Radix revealed significant increase of cell viability of BV-2 microglia cells damaged by nitric oxide. The groups treated with 5 and 50 mg/ml of Puerariae Radix demonstrated increases of cell viabilities of BV-2 microglia cells, but these were not significant statistically. These results suggested that Puerariae Radix revealed neuroprotective effects through the control effect of apoptosis and oxidative damages.