• Title/Summary/Keyword: fragmentation mechanism

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The effect of β-sitosterol proliferation and apoptosis in human uterine leiomyoma cells (계혈등(鷄血藤)의 Beta-sitosterol 성분이 자궁근종세포의 증식억제와 세포자멸사의 유도에 미치는 영향)

  • Park, Youngsun;Baek, Seunghee
    • The Journal of Korean Obstetrics and Gynecology
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    • v.18 no.1
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    • pp.181-191
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    • 2005
  • Purpose : ${\beta}$-sitosterol is kind of phytosterols or plant which are structurally similar to cholesterol. This study was aimed to investigate the inhibitory effect of the ${\beta}$-sitosterol on the proliferation of human uterine leiomyoma cells and the expression of gene related the mechanism of cell apoptosis. Methods : We counted the number of death cells treated with indicated time of the ${\beta}$-sitosterol and investigated cell death rate by cell count assay. Furthermore, flow cytometry analysis and DNA fragmentation assay were used to dissect between necrosis and apoptosis. and then we observed the differential gene expression by western blot analysis. Results : 1) The inhibitory effect on the growth of uterine leiomyoma cell treated with the ${\beta}$-sitosterol $16{\mu}M$ was increased in a time dependent. 2) The result of flow cytometry analysis, subG1 phase arrest related cell apoptosis was investigated 16.97% in uterine leiomyoma cell treated with the ${\beta}$-sitosterol $16{\mu}M$ and showed the fashion of proportional time dependent. 3) The gene expression of p27, p21 related cell cycle was increased according to increasing time interval but cyclin E-CDK2 complex was decreased expression. 4) The character of apoptosis, DNA fragmentation was significantly observed on the time dependent. 5) The expression of pro-caspase 3 and PARP were decreased dependent on treatment with time dependent. Conclusion : This study showed that the ${\beta}$-sitosterol have the inhibitory effect on the proliferation of human uterine leiomyoma cell and the effect was related with apoptosis.

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Protective Effects of Potassium Ion on Rotenone-Induced Apoptosis in Neuronal (Neuro 2A) Cells

  • Park, Ji-Hwan;Kim, Yun-Ha;Moon, Seong-Keun;Kim, Tae-Young;Kim, Jong-Moon
    • Journal of Korean Neurosurgical Society
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    • v.38 no.6
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    • pp.456-464
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    • 2005
  • Objective : The authors investigated whether rotenone induces cellular death also in non-dopaminergic neurons and high concentration of potassium ion can show protective effect for non-dopaminergic neuron in case of rotenone-induced cytotoxicity. Methods : Neuro 2A cells was treated with rotenone, and their survival as well as cell death mechanism was estimated using 3-[4,5-Dimethylthiazol-2-yl]-2,5-diphenyltetrazolium[MTT] assay, Lactate dehydrogenase[LDH] release assay, fluorescence microscopy, and agarose gel electrophoresis. The changes in rotenone-treated cells was also studied after co-treatment of 50mM KCl. And the protective effect of KCl was evaluated by mitochondrial membrane potential assay and compared with the effects of various antioxidants. Results : Neuro 2A cells treated with rotenone underwent apoptotic death showing chromosome condensation and fragmentation as well as DNA laddering. Co-incubation of neuro 2A cells with 50mM KCl prevented it from the cytotoxicity induced by rotenone. Intracellular accumulation of reactive oxygen species[ROS] resulting by rotenone were significantly reduced by 50mM KCl. Potassium exhibited significantly similar potency compared to the antioxidants. Conclusion : The present findings showed that potassium attenuated rotenone-induced cytotoxicity, intracellular accumulation of ROS, and fragmentation of DNA in Neuro 2A cells. These findings suggest the therapeutic potential of potassium ion in neuronal apoptosis, but the practical application of high concentration of potassium ion remains to be settled.

Anti-proliferative and Apoptotic Activity of Extracts of Lindera glauca Blume root in Human HCT116 Colorectal Cancer Cells (감태나무 뿌리 추출물에 의한 대장암세포의 성장억제 및 세포사멸유도)

  • Kim, Yeah-Un;Moon, Ha-Rin;Han, Inhwa;Yun, Jung-Mi
    • Journal of the Korean Society of Food Culture
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    • v.36 no.2
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    • pp.235-245
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    • 2021
  • Lindera glauca Blume has been used in Korean traditional medicine to treat the symptoms of paralysis, abdominal pain, speech disorders, extravasations, contusions, and pain caused by rheumatoid arthritis. We investigated the effect of L. glauca Blume extracts on the proliferation of colorectal cancer cells in vitro using HCT116 human colorectal cancer cell lines. We also investigated its mechanism of action. For this purpose, we used the MTT assay, western blotting, DNA fragmentation analysis, and flow cytometry. HCT116 cells were cultured in several concentrations of ethanol extracts of L. glauca Blume root (0, 50, 100 ㎍/mL). In this study, colon cancer cell growth was inhibited by L. glauca Blume root extract in a dose-dependent manner. It was associated with induction of apoptosis as assessed by nuclear fragmentation and cell cycle analysis. Apoptosis was assessed using western blotting for TNF-α, IL-6, NF-κB, Caspase-3, PARP, Bax, Bcl-2, and SIRT1. The extract also dose-dependently upregulated the expression Bax, the pro-apoptotic gene and downregulated the expression of the anti-apoptotic gene Bcl-2. Furthermore, the extract enhanced Caspase-3 activity in a dose-dependent manner. Our findings provide evidence that L. glauca Blume extract may mediate its anti-proliferative effect via the modulation of apoptosis.

Protective effect of Lycium barbarum leaf extracts on atopic dermatitis: in vitro and in vivo studies

  • Han Sol Lee;Eun Young Bae;Sun Yung Ly
    • Nutrition Research and Practice
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    • v.17 no.5
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    • pp.855-869
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    • 2023
  • BACKGROUND/OBJECTIVES: Atopic dermatitis (AD) is a chronic disease with an increasing incidence globally; therefore, there is a growing demand for natural compounds effective in treating dermatitis. In this study, the protective effects of Lycium barbarum leaves with and without chlorophyll (LLE and LLE[Ch-]) on AD were investigated in animal models of AD and HaCaT cells. Further, we investigated whether LLE and LLE(Ch-) show any differences in physiological activity. MATERIALS/METHODS: AD was induced by 2,4-dinitrochlorobenzene (DNCB) for three weeks, while NC/Nga mice were fed LLE or LLE(Ch-) extracts for 7 weeks. Serum immunoglobulin E (IgE) and cytokine (tumor necrosis factor [TNF]-α, interleukin [IL]-6, and IL-4) concentrations and the degree of DNA fragmentation in lymphocytes were examined. A histopathological examination (haematoxylin & eosin staining and blue spots of toluidine) of the dorsal skin of mice was performed. To elucidate the mechanism of action, the expression of the thymus and activation-regulated chemokine (TARC) and macrophage-derived chemokine (MDC) were measured in HaCaT cells. RESULTS: Serum IgE and cytokines (TNF-α and IL-6) levels as well as DNA fragmentation of lymphocytes were significantly decreased in AD-induced mice treated with LLE or LLE(Ch-) compared to those of the control group. The epidermal thickness of the dorsal skin and mast cell infiltration in the LLE group significantly reduced compared to that in the control group. The LLE extracts showed no cytotoxicity up to 1,000 ㎍/mL in HaCaT cells. LLE or LLE(Ch-)-treated group showed a reduction of TARC and MDC in TNF-α-and IFN-γ-stimulated HaCaT cells. CONCLUSIONS: These results suggest that LLE potentially improves inflammation by reducing the expression of chemokines that inhibit T helper 2 cell migration. LLE(Ch-) showed similar effects to LLE on blood levels of IgE, TNF-α and IL-6 and protein expression in HaCat cells, but the ultimate effect of skin improvement was not statistically significant. Therefore, both LLE and LLE(Ch-) can be used as functional materials to alleviate AD, but LLE(Ch-) appears to require more research to improve inflammation.

Curing Behavior and Interfacial Properties of Electrodeposited Carbon Fiber/Epoxy Composites by Electrical Resistivity Measurement under Tensile/Compressive Tests (전기증착된 탄소섬유/에폭시 복합재료의 인장/압축 하중하에서의 전기저항 측정법을 이용한 경화 및 계면특성)

  • Park, Joung-Man;Lee, Sang-Il;Kim, Jin-Won
    • Journal of Adhesion and Interface
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    • v.2 no.1
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    • pp.9-17
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    • 2001
  • Curing behavior and interfacial properties were evaluated using electrical resistance measurement and tensile/compressive fragmentation test. Electrical resistivity difference (${\Delta}R$) during curing process was not observed in a bare carbon fiber. On the other hand, ${\Delta}R$ appeared due to the matrix contraction in single-carbon fiber/epoxy composite. Logarithmic electrical resistivity of the untreated single-carbon fiber composite increased suddenly to the infinity when the fiber fracture occurred under tensile loading, whereas that of the ED composite reached relatively broadly up to the infinity. Comparing to the untreated case, interfacial shear strength (IFSS) of the ED treated composite increased significantly in both tensile fragmentation and compressive Broutman test. Microfailure modes of the untreated and the ED treated fiber composite showed the debonding and the cone shapes in tensile test, respectively. For compressive test, fractures of diagonal slippage were observed in both untreated and the ED treated composite. Sharp-end shape fractures exhibited in the untreated composite, whereas relatively dull fractures showed in the ED Heated composite. It is proved that ED treatments affected differently on the interfacial adhesion and microfailure mechanism under tensile/compressive tests.

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Apoptotic Effects and Mechanism Study of Silymarin in DU145 Cells (전립선 암세포에서 silymarin의 고사 유도 효과 및 기전 연구)

  • Kwon Kang-Beom;Kim Eun-Kyung;Park Sung-Joo;Song Ho-Joon;Lee Young-Rae;Park Byung-Hyun;Park Jin-Wzoo;Ryu Do-Gon
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.19 no.6
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    • pp.1552-1556
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    • 2005
  • Silymarin has been known to exert anti-tumoral activity in Korea. However, its molecular mechanism of action is not understood. In this study, we found that silymarin induced apoptosis in androgen-independent prostate cancer DU145 cells as confirmed by DNA fragmentation. Our data demonstrated that silymarin-induced apoptotic cell death was accompanied by activation of caspase-3 and subsequent cleavages of its substrates, poly(ADP-ribose) polymerase (PARP) in a time- and concentration-dependent manner. Also, silymarin-induced apoptotic mechanism of DU145 cells involved the induction of Par-4 protein expression. Taken together, these results suggest that silymarin induces the activation of caspase-3, degradation of PARP, increase of Par-4 expression, and eventually leads to apoptotic cell death.

Mechanism of Growth Inhibition by BCH in HEp2 Human Head and Neck Squamous Cell Carcinoma (사람 두경부 편평세포암종 HEp2 세포에서 BCH에 의한 세포성장 억제기전)

  • Choi, Bong-Kyu;Jung, Kyu-Yong;Cho, Seon-Ho;Kim, Chun-Sung;Kim, Do-Kyung
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.37 no.5
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    • pp.555-560
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    • 2008
  • Amino acid transporters are essential for the growth and proliferation in all living cells. Among the amino acid transporters, the system L amino acid transporters are the major nutrient transport system responsible for the $Na^+$-independent transport of neutral amino acids including several essential amino acids. The L-type amino acid transporter 1 (LAT1), an isoform of system L amino acid transporter, is highly expressed in cancer cells to support their continuous growth and proliferation. 2-Aminobicyclo-(2,2,1)-heptane-2-carboxylic acid (BCH) is a model compound for the study of amino acid transporter as a system L selective inhibitor. We have examined the effect and mechanism of BCH on cell growth suppression in HEp2 human head and neck squamous cell carcinoma. The BCH inhibited the L-leucine transport in a concentration-dependent manner with a $IC_{50}$ value of $51.2{\pm}3.8{\mu}M$ in HEp2 cells. The growth of HEp2 cells was inhibited by BCH in the timeand concentration-dependent manners. The formation of DNA ladder was not observed with BCH treatment in the cells. Furthermore, the proteolytic processing of caspase-3 and caspase-7 in the cells were not detected by BCH treatment. These results suggest that the BCH inhibits the growth of HEp2 human head and neck squamous cell carcinoma through the intracellular depletion of neutral amino acids for cell growth without apoptotic processing.

Protective Effects of Chungsimyeonja-eum on Glutamate-induced Apoptosis in C6 Glial Cells (Glutamate로 유도된 C6 glial 세포 자멸사에 대한 청심연자음(淸心蓮子飮)의 보호효과)

  • Ko, Seok-Jae;Shin, Yong-Jeen;Jang, Won-Seok;Ha, Ye-Jin;Lee, Seon-A;Ahn, Min-Seob;Kwon, Oh-Sang;Shin, Sun-Ho
    • The Journal of Internal Korean Medicine
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    • v.31 no.1
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    • pp.54-65
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    • 2010
  • Objective : The water extract of Chungsimyeonja-eum (CSYJE) has traditionally been used in treatments of heart diseases and brain diseases in Oriental medicine. However, little is known about the mechanism by which CSYJE protects neuronal cells from injury damages. Therefore, in this study we attempted to elucidate the mechanism of the cytoprotective effect of the CSYJE extract on glutamate-induced C6 glial cell death. Methods : Cultured cells were pretreated with CSYJE and exposed to glutamate, cell damage was assessed by using MTT assay and propidium iodide (PI), probe 2',7'-dichlorofluorescein diacetate (DCF-DA) staining. Western blotting was performed using anti-procaspase-3 and anti-PARP, respectively. Result : We determined the elevated cell viability by CSYJE extract on glutamate-induced C6 glial cell death. Glutamate induced DNA fragmentation on C6 glial cells but pre-treatment with CSYJE inhibited DNA fragmentation. One of the main mediators of glutamate-induced cytotoxicity was known to generation of reactive oxygen species (ROS). Pre-treatment with CSYJE inhibited this ROS generation from glutamate-stimulated C6 glial cells. Also, we identified that the ROS-induced DCF-DA green fluorescence was reduced by CSYJE pre-treatment. The critical markers of apoptotic cell death are the cleavages of procaspase-3 protease and PARP proteins, so we checked the expression level and cleavages of procaspase-3 protease and PARP proteins. Glutamate-treated C6 glial cells showed the cleavages of procaspase-3 protease and PARP proteins and followed the reduction of expression of these proteins. Conclusion : These findings indicate that CSYJE may prevent cell death from glutamate-induced C6 glial cell death by inhibiting the ROS generation and procaspase-3 and PARP expression.

A Multicast Middleware for the Remote Educational Systems (원격 교육 시스템을 위한 멀티캐스트 미들웨어)

  • Byun, Sang-Seon;Jin, Hyun-Wook;Yoo, Hyuck
    • Journal of KIISE:Computing Practices and Letters
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    • v.9 no.1
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    • pp.100-108
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    • 2003
  • By choosing Multicast for transmission of educational contents in the Remote Educational System, we can reduce the server load and increase network bandwidth utilization. We design and implement Multicast Middleware for the Remote Educational System in this paper. There are three characteristics in this Multicast Middleware: 1) Through Centralized Multicast Group Management for passive members, it allows a host to make multicast group, which is composed of receivers, called Group Member and who are chosen by the host, called group Maker. Because, all groups are created by the Group Maker in Centralized Group Management, Group Member's join action will be passive 2) Maintenance and recovery of multicast group information in order to restore from exception and crash; the maintenance and recovery mechanism of Group Maker is distinct from that of Group Member. 3) The mechanism which enables to transmit large size multimedia data through multicasting and remove additional copy operation through shared buffer. Fragmentation/de-fragmentation for large data delivery results in additional copy operation in user level. But by using user level shared buffer, it can be done without user Bevel copy operation. By applying to Remote Educational environment which consists of 30 PCs and Fast Ethernet, we can examine the efficiency of this middleware, which can transmit 18frames/sec movie which resolution 320 $\times$ 120 pixels, 128Kbps encoded sound data and some text data.

Effects of epigallocatechin gallate on $CoCl_2-induced$ apoptosis in PC12 cells (PC12 세포에서 $CoCl_2$ 유발 세포자멸사에 대한 epigallocatechin-gallate의 역할)

  • Mo, Hyun-Chul;Choi, Nam-Ki;Kim, Seon-Mi;Kim, Won-Jae;Yang, Kyu-Ho
    • Journal of the korean academy of Pediatric Dentistry
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    • v.33 no.1
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    • pp.13-24
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    • 2006
  • Neuronal apoptotic events, consequently resulting in neuronal cell death, are occurred in hypoxic/ischemic condition. This cell death has been shown to be accompanied with the production of reactive oxygen species (ROS), which can attack cellular components such as nucleic acids, proteins and phospholipid. However, the underlying mechanisms of apoptosis induced in hypoxic/ischemic condition and its treatment methods are unsettled. Cobalt chloride $(CoCl_2)$ has been known to mimic hypoxic condition including the production of ROS. Epigallocatechin gallate (EGCG), a green tea polyphenol, has diverse pharmacologial activities in cell growth and death. This study was aimed to investigate the apoptotic mechanism by $CoCL_2$ and effects of EGCG on $CoCl_2-induced$ apoptosis in PC12 cells. Administration of $CoCl_2$ decreased cell survival in dose- and time-dependent manners and induced genomic DNA fragmentation. Treatment with $100{\mu}M$ EGCG for 30 min before PC12 cells were exposed to $150{\mu}M$ $CoCl_2$, being resulted in the cell viability and DNA fragmentation being rescued. $CoCl_2$ caused morphologic changes such as cell swelling and condensed nuclei whereas EGCG attenuated morphologic changes by $CoCl_2$. EGCG suppressed the apoptotic peak and a loss of ${\Delta}{\psi}_m$ induced by $CoCl_2$. $CoCl_2$ decreased Bcl-2 expression but Bax expression was not changed in $CoCl_2$- treated cells. EGCG attenuated the Bcl-2 underexpression by $CoCl_2$. $CoCl_2$ augumented the cytochrome c release from mitochondria into cytoplasm and increased caspase-8, -9 and caspase-3 activity a marker of the apoptotic executing stage. EGCG ameliorated the incruement in caspase-8, -9 and -3 activity, and cytochrome c release by $CoCl_2$ NAC (N-acetyl-cysteine), a scavenger of ROS, attenuated $CoCl_2-induced$ apoptosis in consistent with those of EGCG. These results suggest that $CoCl_2$ induces apoptotic cell death through both mitochondria- and death receptor-dependent pathway and EGCG has neuroprotective effects against $CoCl_2-induced$ apoptosis in PC12 cells.

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