• Title/Summary/Keyword: Human Cell

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Cytotoxicity of Mifepristone via Calcium Modulation In Human Prostate Cancer Cells (인간 전립선암세포에 있어서 칼슘조절을 통한 mifepristone의 세포독성효과)

  • Song, Hwi-June;Kim, Byeong-Gee
    • Journal of Life Science
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    • v.19 no.7
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    • pp.892-898
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    • 2009
  • MIF is a progesterone analogue and is known as a potent progesterone antagonist. Although MIF has been known to inhibit prostate cancer cell growth, its molecular mechanisms are not yet clear. In the present study, when the cells were treated for 2-4 days with 5-40 $\mu$M of MIF, the growth and viability of LNCaP cells were significantly decreased in a dose- and time-dependent manner. When the cells, cultivated in a normal 2 mM calcium concentration medium, were treated with 15 $\mu$M MIF for 1 day, the intracellular calcium level increased by 26% compared to the control. Similar results were also found in cells located in the calcium-free reaction buffer, indicating that MIF induced the increase of intracellular Ca$^{2+}$ levels, regardless of the presence of calcium in the surrounding medium. In the cells treated with various concentrations of MIF, the intracellular calcium levels increased in a dose dependent manner. Cells treated with MIF revealed typical early apoptotic signs, i.e., chromosome condensation and nuclei fragmentation. In cells treated with 40 11M MIF, Bcl-2 decreased to 19% of the control. The expression of Bax increased to almost 2 fold of the control. These results demonstrated very clearly that MIF treatment blocks the expression of Bcl-2 but stimulates the expression of Bax. According to the results of the present investigation, the apoptotic mechanism of MIF is triggered by intracellular modulation.

Ecology of Groundwater Microorganisms in Aquifers (대수층 지하수 미생물의 생태)

  • Kim, Young-Hwa;Ahn, Yeonghee
    • Journal of Life Science
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    • v.27 no.9
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    • pp.1086-1095
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    • 2017
  • There is growing interest in groundwater resources to overcome the loss of surface water resources due to climate change. An understanding of the microbial community of aquifers is essential for monitoring and evaluating groundwater contamination, as well as groundwater management. Most microorganisms that inhabit aquifer ecosystems are attached to sediment particles rather than planktonic, as is the case in groundwater. Since sampling aquifer sediment is not easy, groundwater, which contains planktonic microorganisms, is generally sampled in microbial community research. Although many studies have investigated microbial communities in contaminated aquifers, there are only a few reports of microbial communities in uncontaminated or pristine aquifers, resulting in limited information on aquifer microbial diversity. Such information is needed for groundwater quality improvement. This paper describes the ecology and community structure of groundwater bacteria in uncontaminated aquifers. The diversity and structures of microbial communities in these aquifers were affected by the concentration or distribution of substrates (e.g., minerals, organic matter, etc), in addition to groundwater characteristics and human activities. Most of the microbial communities in these uncontaminated aquifers were dominated by Proteobacteria. Studies of microbial communities in uncontaminated aquifers are important to better understand the biogeochemical processes associated with groundwater quality improvement. In addition, information on the microbial communities of aquifers can be used as a basis to monitor changes in community structure due to contamination.

Cariporide Enhances the DNA Damage and Apoptosis in Acid-tolerable Malignant Mesothelioma H-2452 Cells

  • Lee, Yoon-Jin;Bae, Jin-Ho;Kim, Soo-A;Kim, Sung-Ho;Woo, Kee-Min;Nam, Hae-Seon;Cho, Moon-Kyun;Lee, Sang-Han
    • Molecules and Cells
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    • v.40 no.8
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    • pp.567-576
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    • 2017
  • The $Na^+/H^+$ exchanger is responsible for maintaining the acidic tumor microenvironment through its promotion of the reabsorption of extracellular $Na^+$ and the extrusion of intracellular $H^+$. The resultant increase in the extracellular acidity contributes to the chemoresistance of malignant tumors. In this study, the chemosensitizing effects of cariporide, a potent $Na^+/H^+-exchange$ inhibitor, were evaluated in human malignant mesothelioma H-2452 cells preadapted with lactic acid. A higher basal level of phosphorylated (p)-AKT protein was found in the acid-tolerable H-2452AcT cells compared with their parental acid-sensitive H-2452 cells. When introduced in H-2452AcT cells with a concentration that shows only a slight toxicity in H-2452 cells, cariporide exhibited growth-suppressive and apoptosis-promoting activities, as demonstrated by an increase in the cells with pyknotic and fragmented nuclei, annexin V-PE(+) staining, a $sub-G_0/G_1$ peak, and a $G_2/M$ phase-transition delay in the cell cycle. Preceding these changes, a cariporide-induced p-AKT down-regulation, a p53 up-regulation, an ROS accumulation, and the depolarization of the mitochondrial-membrane potential were observed. A pretreatment with the phosphatidylinositol-3-kinase (PI3K) inhibitor LY294002 markedly augmented the DNA damage caused by the cariporide, as indicated by a much greater extent of comet tails and a tail moment with increased levels of the p-histone H2A.X, $p-ATM^{Ser1981}$, $p-ATR^{Ser428}$, $p-CHK1^{Ser345}$, and $p-CHK2^{Thr68}$, as well as a series of pro-apoptotic events. The data suggest that an inhibition of the PI3K/AKT signaling is necessary to enhance the cytotoxicity toward the acidtolerable H-2452AcT cells, and it underlines the significance of proton-pump targeting as a potential therapeutic strategy to overcome the acidic-microenvironment-associated chemotherapeutic resistance.

Skin Whitening and Skin Immune Activities of Different Parts of Acer mono and Acer okamotoanum (고로쇠 및 우산고로쇠나무의 부위별 미백 및 피부면역 활성)

  • Jeong, Myoung-Hoon;Kim, Seung-Seop;Kim, Ji-Seon;Lee, Hak-Ju;Chio, Geun-Pyo;Lee, Hyeon-Yong
    • Journal of Korean Society of Forest Science
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    • v.99 no.4
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    • pp.470-478
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    • 2010
  • UV-protection skin whitening and immune activities several parts of Acer mono and Acer okamotoanum were investigated. The bark of both Acer mono and Acer okamotoanum had higher yields than other parts as 2.67% and 2.45%. The cytotoxicity of the extracts were lower than 21.64% against human skin cell(CCD-986sk) line in adding 1.0 mg/mL of the highest concentration. The bark extracts of Acer mono greatly reduced the expression of MMP-1 on UV-irradiated CCD-986sk cells down to as 30%. At 1.0 mg/mL of bark extration of Acer mono, $PGE_2$ expression was also significantly decreased. Generally, the bark extracts of Acer mono and Acer okamotoanum had higher activity than other parts, but, interestingly, wood extract of Acer okamotoanum showed strong inhibition effect on melanin production by Clone-M3 cells as 79.25%. From these results, we could conclude that the bark extract from Acer mono and Acer okamotoanum had skin-whitening activity as well immune enhancement activity.

Beneficial Effects of Herbal Mixture (JAUN-1) on 0.1% Iodoacetamide-induced Gastritis Rat Model (0.1% Iodoacetamide에 의해 유도된 흰쥐 위염 모델에서 한약처방(JAUN-1)의 유익한 효능규명)

  • Han, Kyung-Ju;Koo, Sung-Tae;Hwang, Hye-Suk;Kim, Yu-Sung;Lee, Ji-Eun;Ko, Mi-Mi;Jung, Bong-Yeon;Choi, Sun-Mi
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.21 no.6
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    • pp.1549-1554
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    • 2007
  • To verify the effects of JAUN-1, which is a water-extracted herbal mixture, on gastroenteric disorders induced by 0.1 percent of iodoacetamide (IA) in rats. We divided four groups, $Na{\"{\i}}ve$ + Distilled Water (DW), 0.1% IA + DW, 0.1% IA + Proton pump inhibitor (Lansoprazole, 5 mg/kg) and 0.1% IA + Herbal mixture (JAUN-1, 50mg/kg) and performed following experimental methods to confirm its advantageous effects against ulcerogenic stomach in rats induced by 0.1% IA; cell cytotoxicity, analysis of lesions score, Hematoxylin & Eosin (H&E) stain, RT-PCR for ${\beta}-actin$, COX-1 and COX-2 and evaluation of intestinal prokinetic activity. No cytotoxicity was elucidated at the concentration of 1, 5, 10, 50, 100, $500\;{\mu}g/ml$ and 1mg/ml JAUN-1 through MTT Assay using by human stomach epithelial AGS cells, respectively. In addition, the JAUN-1 treated group and the lansoprazole treated group significantly decreased in lesions score compared to the DW treated group in the gastritis induced rat model, and results of immunohistochemistry by H&E staining showed that histological recovery in Proton Pump Inhibitor (PPI) and JAUN-1 treated groups rather than the DW administrated group. Another outcome was that ${\beta}-actin$ relative COX-2 expression level was significantly promoted in the DW treated group while ${\beta}-actin$ relative COX-1 expression level was no meaningful change in this rat model. Finally, intestinal prokinetic activity was recovered from low level of prokinetic activity due to 0.1% IA induced gastritis to the similar level of Normal group. These results suggested that JAUN-1 may have beneficial effects against 0.1% IA-induced gastritis rat model through decreasing lesions score, histological recovery, ${\beta}-actin$ relative COX-1, 2 expression level and prokinetic activity.

Development of an aequorin-based assay for the screening of corticotropin-releasing factor receptor antagonists (CRF1 길항제 스크리닝을 위한 에쿼린 기반 세포실험 개발연구)

  • Noh, Hyojin;Lee, Sunghou
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.11
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    • pp.7575-7581
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    • 2015
  • Corticotropin-releasing factor(CRF), one of the stress driven neuropeptides, was widely proposed to influence hair loss and re-growth. For the development of receptor antagonists, the screening system based on intracellular calcium signal process was developed and optimized. The aequorin parental cells were transfected with CRF1 receptor and alpha 16 promiscuous G protein cDNA to establish HEK293a16/hCRF1, a stable cell line for the human CRF1 receptor. In HEK293a16/hCRF1 cells, the range of sauvagine dose response was 12-fold higher($EC_{50}:15.21{\pm}1.83nM$) than in the transiently expressed cells, hence essential conditions for the antagonist screening experiments such as the robust signals and high solvent tolerance were secured. The standard antagonists for the CRF1 receptor, antalarmin and CP154526, resulted $IC_{50}$ values of $414.1{\pm}5.5$ and $290.7{\pm}1.9nM$, respectively. Similar results were presented with frozen HEK293a16/hCRF1 cells. Finally, our HEK293a16/hCRF1 cells with the aequorin based cellular functional assay can be a model system for the development of functional cosmetics and modulators that can have a clinical efficacy on hair re-growth.

Eine Structure of Digital Arteries in Rat (흰쥐 수지동맥의 미세구조에 관한 연구)

  • Kim, Baik-Yoon;Shin, Keun-Nam
    • Applied Microscopy
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    • v.29 no.1
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    • pp.83-94
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    • 1999
  • The ultrastructure of small arterioles and capillaries in the lumbrical muscles of rat digits were studied by electron microscopy and following results were obtained. 1. The diameter of small arterioles of rat digits were $12\sim20{\mu}m$, and it was relatively smaller than human $(30\sim35{\mu}m)$. 2. All the endothelial cells of small arterioles and capillaries in the lumbrical muscles of rat digits were continuous type, and they had typical morphological characteristics of continuous endothelial cells : numerous cytoplasmic pinocytic vesicles and many tight junctions between the endothelial cells. 3. In the small arterioles subendothelial layers were irregularly spaced beneath the basal lamina, and membrane to membrane contacts were found between the endothelial cells and smooth muscle cells. 4. Pericytes were often found nearby capillary endothelium, and their cytoplasmic processes surrounded part of endothelial cells. They were enclosed by basal lamina. 5. Smooth muscle cells in tunica media of small arterioles were only one layered, that is, they were terminal arterioles. Sarcoplasm of smooth muscle cell was divided to 2 areas; homogeneous or filamentous area and non-homogeneous perinuclear area. 6. The tunica adventitia contained fibroblasts with extremely attenuated cytoplasmic processes and collagen fibirls.

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Silybin Synergizes with Wnt3a in Activation of the Wnt/${\beta}$-catenin Signaling Pathway through Stabilization of Intracellular ${\beta}$-Catenin Protein (Silybin에 의한 Wnt/${\beta}$-catenin 신호전달체계의 활성화)

  • Kim, Tae-Yeoun;Oh, Sang-Taek
    • Microbiology and Biotechnology Letters
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    • v.40 no.1
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    • pp.50-56
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    • 2012
  • The Wnt/${\beta}$-catenin signaling pathway regulates diverse developmental processes and adult tissue homeostasis. Inappropriate regulation of this pathway has been associated with human diseases, such as cancers, osteoporosis, and Alzheimer's disease. Using a cell-based chemical screening with natural compounds, we discovered silybin, a plant flavonoid isolated from the Silybum marianum, which activated the Wnt/${\beta}$-catenin signaling pathway in a synergy with Wnt3a-conditioned medium (Wnt3a-CM). In the presence of Wnt3a-CM, silybin up-regulated ${\beta}$-catenin response transcription (CRT) in HEK293-FL reporter cells and 3T3-L1 preadipocytes through stabilization of intracellular ${\beta}$-catenin protein. Silybin and Wnt3a-CM synergistically reduced expression of important adipocyte marker genes including peroxisome-proliferator-activated $receptor{\gamma}$ ($PPAR{\gamma}$) and CAATT enhancer-binding protein ${\alpha}$ (C/$EBP{\alpha}$) in 3T3-L1 preadipocytes, accompanied by the activation of Wnt/${\beta}$-catenin signaling pathway. Taken together, our findings indicate that silybin is a small-molecule synergist of the Wnt/${\beta}$-catenin signaling pathway and can be used as a controllable reagent for investigating biological processes that involve the Wnt/${\beta}$-catenin signaling pathway.

Screening of $\alpha$-Amylase and $\alpha$-Glucosidase Inhibitor from Nepalese Plant Extracts (100종 네팔 식물 추출물로부터 $\alpha$-Amylase 및 $\alpha$-Glucosidase저해제의 선별)

  • Kim, Mi-Sun;Ahn, Seon-Mi;Jung, In-Chang;Kwon, Gi-Seok;Sohn, Ho-Yong
    • Microbiology and Biotechnology Letters
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    • v.38 no.2
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    • pp.183-189
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    • 2010
  • In the course of screening for anti-acidosis and anti-diabetes agent from natural products, the inhibitory activities of Nepales plant extracts against microbial $\alpha$-amylase and $\alpha$-glucosidase were evaluated. Among the 100 different kinds of ethanol extracts, Cedrus deodara (Roxb.) G. Don and Myrica nagi Thunb showed strong inhibition activities against $\alpha$-amylase. The $IC_{50}$ values of C. deodara (Roxb.) G. Don, M. nagi Thunb and acarose, a commercial available anti-diabetes agent, were 44.5, 47.5 and $50.5\;{\mu}g/mL$, respectively. Considering the crude extract of C. deodara (Roxb.) G. Don, and M. nagi Thunb, these extracts have strong potentials as anti-acidosis or anti-diabates agent. In a while, Cleistocalyx operculatus (Roxb.) extract showed a good inhibition activity to $\alpha$-amylase and $\alpha$-glucosidase, even it was recently reported. The selected three extracts did not show any hemolysis activity against human red blood cell up to 1 mg/mL, and the inhibition activities were maintained by heat or acid treatment. Moreover, treatment of HCl (0.01N) for 1 h into C. operculatus (Roxb.) and M. nagi Thunb increased the inhibition activity from 50% to 70%. Our results suggest that C. deodara (Roxb.) G. Don, M. nagi Thunb, and C. operculatus (Roxb.) are potential as anti-acidosis and anti-diabetes agents.

Summary on the Dinoflagellate Cyst Assemblages of Modern Sediments from Korean Coastal Waters and Adjoining Sea (한국연안해역 와편모조류 시스트 연구에 관한 고찰)

  • Yoon, Yang Ho;Shin, Hyeon Ho
    • Korean Journal of Environmental Biology
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    • v.31 no.4
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    • pp.243-274
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    • 2013
  • To investigate the research state and characteristics of dinoflagellate cyst along the Korean coastal waters, this work analyzed 45 studies conducted in the Korean coasts and basin, the south of Jeju, East China Sea including some part of the Yellow Sea. It was found that the research on dinoflagellate cyst began in the later half of the 1980s in Korea, and that the research areas focused on eutrophied regions where a red tide occurred or on the seas where coastal development occurred. In other words, no research on the East Sea was found. In terms of research contents, there were various studies on analysis of cyst assemblage, tracking of the changes in marine environment like process of eutrophication, roles as a seed population in occurrence of a red tide, creation of cyst by use of sediment trip and tracking of its changes, morphological changes by the change of pH concentration in the hypoxia zone of eutrophied region, germination of a specific species, and other international-level studies. Species composition and cell density also varied in the Korean coastal waters. However, much research on dinoflagellate cyst in Korea is not systematic, and is fragmentary and individual and hencesuffers from great limitations. The research results so far have focused only on specific regions, and sporadic research had been conducted by specific research groups. Dinoflagellate cyst of surface sediments represents the accumulation index of pelagic environment in the sea and is a useful index to understand the marine environment efficiently. In conclusion, Korea requires organized human resources and collaborative research on dinoflagellate cyst which in turn should be considered as a component of marine ecosystem and as an essential aspect of marine biology.