• Title/Summary/Keyword: fragmentation mechanism

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Antitumor Activity of Methylene Chloride Fraction from Angelica Keiskei Through Induction of Apoptosis in Human Prostate Carcinoma DU145 Cells (전립선 암세포주 DU145의 세포고사 유도를 통한 신선초 (Angelica keiskei) 메틸렌 클로라이드 추출물의 항암효과)

  • Kang, Yoon-Mook;Kim, Sung-Moo;Kim, Hyun-Jung;Park, Kyung-Ran;Shim, Bum-Sang;Kim, Sung-Hoon;Choi, Seung-Hoon;Ahn, Kyoo-Seok;Ahn, Kwang-Seok
    • Journal of Korean Traditional Oncology
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    • v.15 no.1
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    • pp.19-27
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    • 2010
  • The roots and leaves of Angelica keiskei (AK) have been used for the treatment of various diseases including coronary heartdisease, hypertension, and cancer in the Korean folk medicine. However, the mechanism by which methylenechloride fraction (MF) from AK exerts anti-tumorigenic activity in human prostate cancer cells has not been fully understood. In the present study, we report the MF exerted the highest cytotoxicity against prostate cancer DU145 cells compared with other fractions. Especially, MF caused the accumulation of sub-G1 DNA contents of cell cycle and increased annexin V-positive apoptotic bodies and DNA fragmentation. MF down-regulated several proliferative (Cyclin D1) and anti-apoptotic (Bcl-xl, Bcl-2, IAP-1/2, and survivin)gene products in these cells. Hence, MF induced apoptosis through the caspase-3 activation in DU145 cells. We further confirmed that caspase-3 plays an importance role in MF-induced apoptosis in DU145 cells by using caspase-3 inhibitor. Additionally, we observed that MF potentiated Dox-induced apoptosis in DU145 cells. Taken together, our data demonstrate the evidence that MF induces apoptosis depend on caspase-3 activation of and overcomes resistance to chemotherapy in human prostate cancer cells.

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Curcumin Attenuates Hydrogen Peroxide Induced Oxidative Stress on Semen Characteristics during In Vitro Storage of Boar Semen

  • Jang, Hyun-Yong;Kim, Young-Han;Cheong, Hee-Tae;Kim, Jong-Taek;Park, In-Chul;Park, Choon-Keun;Yang, Boo-Keun
    • Reproductive and Developmental Biology
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    • v.33 no.2
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    • pp.99-105
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    • 2009
  • Curcumin is a major active component of the food flovour tumeric. It has been used for the treatment of many diseases such as inflammatory and infectious diseases, cancer and other disease due to its antioxidant properties. Curcumin is a powerful scavenger of many free radicals such as superoxide anion, hydroxyl radical and nitric oxide. The objective of this study was to investigate the antioxidative effects of curcumin against hydrogen peroxide on semen quality during in vitro storage of boar semen. The sperm treated with different concentration of curcumin (1, 5 and 10 ${\mu}M$) in the presence or absence of hydrogen peroxide (250 ${\mu}M\;H_2O_2$) were incubated for 3, 6 and 9 hr at $37^{\circ}C$ and analyzed sperm characteristics such as motility, membrane integrity (MI), lipid peroxidation (LPO), reactive oxygen species (ROS) and DNA fragmentation (DF). The sperm motility and MI in $H_2O_2$ treated group ($47.8%{\pm}6.8$ and $24.8%{\pm}2.2$) were significantly decreased when compare to curcumin treated group ($79.8%{\pm}2.7$ and $34.6%{\pm}1.0$, respectively) irrespective of incubation periods(p<0.05). The LPO of spermatozoal plasma membrane was measured by thiobarbituric acid (TBA) reactions for malondialdehyde (MDA), MDA level in control ($11.6{\pm}0.6\;nmol/L{\times}10^6$) and curcumin groups ($10.7{\pm}0.3\;nmol/L{\times}10^6$) were lower than those of curcumin plus $H_2O_2$ ($17.1{\pm}0.8\;nmol/L{\times}10^6$) or $H_2O_2$ group ($22.5{\pm}1.9\;nmol/L{\times}10^6$) from 3 to 9 hr incubation periods. The DF by sperm chromatin dispersion (SCD) test and ROS production measured by 2',7'-dichlorofluorescein (DCF) fluorescence intensity were no significantly difference through all experimental groups (p>0.05). Correlation among evaluation methods for sperm quality, motility vs MI and DF vs ROS was positively correlated while motility vs DF and ROS vs LPO were negatively correlated in all treatment groups. These results demonstrate that curcumin can effectively improve the sperm quality during in vitro storage of boar semen through its hydrogen peroxide scavenging mechanism as an antioxidant.

Roles of p53 and Caspases in Induction of Apoptosis in MCF-7 Breast Cancer Cells Treated with a Methanolic Extract of Nigella Sativa Seeds

  • Alhazmi, Mohammed I.;Hasan, Tarique N.;Shafi, Gowhar;Al-Assaf, Abdullah H.;Alfawaz, Mohammed A.;Alshatwi, Ali A.
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.22
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    • pp.9655-9660
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    • 2014
  • Background: Nigella Sativa (NS) is an herb from the Ranunculaceae family that exhibits numerous medicinal properties and has been used as important constituent of many complementary and alternative medicines (CAMs). The ability of NS to kill cancer cells such as PC3, HeLa and hepatoma cells is well established. However, our understanding of the mode of death caused by NS remains nebulous. The objective of this study was to gain further insight into the mode and mechanism of death caused by NS in breast cancer MCF-7 cells. Materials and Methods: Human breast cancer cells (MCF-7) were treated with a methanolic extract of NS, and a dose- and time-dependent study was performed. The $IC_{50}$ was calculated using a Cell Titer $Blue^{(R)}$ viability assay assay, and evidence for DNA fragmentation was obtained by fluorescence microscopy TUNEL assay. Gene expression was also profiled for a number of apoptosis-related genes (Caspase-3, -8, -9 and p53 genes) through qPCR. Results: The $IC_{50}$ of MCF-7 cells was $62.8{\mu}L/mL$. When MCF-7 cells were exposed to $50{\mu}L/mL$ and $100{\mu}L/mL$ NS for 24h, 48h and 72h, microscopic examination (TUNEL assay) revealed a dose- and time-dependent increase in apoptosis. Similarly, the expression of the Caspase-3, -8, -9 and p53 genes increased significantly according to the dose and time. Conclusions: NS induced apoptosis in MCF-7 cells through both the p53 and caspase pathways. NS could potentially represent an alternative source of medicine for breast cancer therapy.

The Role of ROS and p38 MAP kinase in Berberine-Induced Apoptosis on Human Hepatoma HepG2 Cells (Berberine에 의한 HepG2 세포의 사멸과정에서 활성기산소와 p38 MAP kinase의 역할에 관한 연구)

  • Hyun, Mee-Sun;Woo, Won-Hong;Hur, Jung-Mu;Kim, Dong-Ho;Mun, Yeun-Ja
    • Applied Biological Chemistry
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    • v.51 no.2
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    • pp.129-135
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    • 2008
  • Berberine is an isoquinoline alkaloid used in traditional Chinese medicine and has been isolated from a variety of plants, such as Coptis chinensis and Phellodendron amurense. It has a wide spectrum of clinical applications such as in anti-tumor, anti-microbial, and anti-inflammatory activities. However, it is still unknown that berberine related with reactive oxygen species (ROS)-mediated apoptosis pathway in human hepatoma HepG2 cells. In the present study, we are examined the molecular mechanism of ROS- and p38 MAP kinase-mediated apoptosis by berberine in HepG2 cells. Berberine increased cytotoxicity effects by time- and does-dependent manner. $LD_{50}$ was detected 50 ${\mu}M$ at 48h of exposure to berberine. Nuclei cleavage and apoptotic DNA fragmentation were observed in cells treated with 50 ${\mu}M$ of berberine for 48h. Moreover, berberine induced the activating of caspase-3, p53, p38 and Bax expression, whereas the expression of anti-apoptotic signaling pathways, Bcl-2, was decreased. Additionally, berberine-treated cells had an increased level of generation of ROS and nitric oxide (NO). These results indicated that berberine induces apoptosis of HepG2 cells may be mediated oxidative injury acts as an early and upstream change, triggers mitochondrial dysfunction, Bcl-2 and Bax modulation, p38 and p53 activation, caspase-3 activation, and consequent leading to apoptosis.

Protective effects skin keratinocyte of Oenothera biennis on hydrogen peroxide-induced oxidative stress and cell death via Nrf2/Ho1 pathway.

  • Lee, Seung Young;Jung, Ji Young;Choi, Hee Won;Choi, Kyung Min;Jeong, Jin-Woo
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2018.10a
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    • pp.103-103
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    • 2018
  • Oenothera biennis, commonly known as evening primrose, a potential source of natural bioactive substances: flavonoids, steroids, tannins, fatty acids and terpenoids responsible for a diverse range of pharmacological functions. However, whether extract prepared from aerial part of O. biennis (APOB) protects skin against oxidative stress remains unknown. To investigate the protective effects of APOB against oxidative stress-induced cellular damage and elucidated the underlying mechanisms in the HaCaT human skin keratinocytes. Our results revealed that treatment with APOB prior to hydrogen peroxide ($H_2O_2$) exposure significantly increased viability, and the highest DPPH radical-scavenging activities and reducing power of HaCaT cells. APOB also effectively attenuated H2O2-induced comet tail formation and inhibited the $H_2O_2$-induced phosphorylation levels of the histone ${\gamma}H2AX$, as well as the number of apoptotic bodies and Annexin V-positive cells. In addition, APOB exhibited scavenging activity against intracellular reactive oxygen species (ROS) accumulation and restored the mitochondrial membrane potential loss by $H_2O_2$. Moreover, $H_2O_2$ enhanced the cleavage of caspase-3 and degradation of poly (ADP-ribose)-polymerase (PARP), a typical substrate protein of activated caspase-3, as well as DNA fragmentation; however, these events were almost totally reversed by pretreatment with APOB. Furthermore, APOB increased the levels of heme oxygenase-1 (HO-1), which is a potent antioxidant enzyme, associated with the induction of nuclear factor-erythroid 2-related factor 2 (Nrf2). According to our data, APOB is able to protect HaCaT cells from $H_2O_2$-induced DNA damage and cell death through blocking cellular damage related to oxidative stress through a mechanism that would affect ROS elimination and activating the Nri2/HO-1 signaling pathway.

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How does Welfare State Colonize the Private Spheres : Political Fragmentation and Depoliticization (복지국가는 사적 공간을 어떻게 식민화하는가 : 정치의 분절화와 탈정치화)

  • Han, Dongwoo;Choi, Hyeji
    • Korean Journal of Social Welfare
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    • v.67 no.2
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    • pp.161-181
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    • 2015
  • This article tries to identify the regulating mechanism of the welfare states on the private spheres of individuals and families. When the welfare state is to be understood as an institutional arrangement which is based upon the 'modernity', the reflectivity on the welfare state is about to be on the modernity and on the institutions as well. Authors assume the welfare state as an historical and developmental type of modern states. The critical components of modernity embedded in birth and growth of modern welfare states projected to their institutions are identified. Welfare states dissociates the political dynamics which have built the foundation of the welfare state itself, and faces against the new political dynamics of the individualized society. Finally, welfare state confronts the institution failure due to its intrinsic characteristics, and consequently individuals and families come across the institution dependency. Individuals in the overly rationalized spheres are being depoliticized, and they are identified themselves as the subjects of status-struggles of the institutions other than the subjects of the political dynamics of welfare states.

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Acacetin-induced Apoptosis of Human Breast Cancer MCF-7 Cells Involves Caspase Cascade, Mitochondria-mediated Death Signaling and SAPK/JNK1/2-c-Jun Activation

  • Shim, Hye-Young;Park, Jong-Hwa;Paik, Hyun-Dong;Nah, Seung-Yeol;Kim, Darrick S.H.L.;Han, Ye Sun
    • Molecules and Cells
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    • v.24 no.1
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    • pp.95-104
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    • 2007
  • The mechanism of acacetin-induced apoptosis of human breast cancer MCF-7 cells was investigated. Acacetin caused 50% growth inhibition ($IC_{50}$) of MCF-7 cells at $26.4{\pm}0.7{\mu}M$ over 24 h in the MTT assay. Apoptosis was characterized by DNA fragmentation and an increase of sub-G1 cells and involved activation of caspase-7 and PARP (poly-ADP-ribose polymerase). Maximum caspase 7 activity was observed with $100{\mu}M$ acacetin for 24 h. Caspase 8 and 9 activation cascades mediated the activation of caspase 7. Acacetin caused a reduction of Bcl-2 expression leading to an increase of the Bax:Bcl-2 ratio. It also caused a loss of mitochondrial membrane potential that induced release of cytochrome c and apoptosis inducing factor (AIF) into the cytoplasm, enhancing ROS generation and subsequently resulting in apoptosis. Pretreatment of cells with N-acetylcysteine (NAC) reduced ROS generation and cell growth inhibition, and pretreatment with NAC or a caspase 8 inhibitor (Z-IETD-FMK) inhibited the acacetin-induced loss of mitochondrial membrane potential and release of cytochrome c and AIF. Stress-activated protein kinase/c-Jun $NH_4$-terminal kinase 1/2 (SAPK/JNK1/2) and c-Jun were activated by acacetin but extracellular-regulated kinase 1/2 (Erk1/2) nor p38 mitogen-activated protein kinase (MAPK) were not. Our results show that acacetin-induced apoptosis of MCF-7 cells is mediated by caspase activation cascades, ROS generation, mitochondria-mediated cell death signaling and the SAPK/JNK1/2-c-Jun signaling pathway, activated by acacetin-induced ROS generation.

Inhibition of pRB Phosphorylation and Induction of p21WAF1/CIP1 Occur During cAMP-induced Growth Arrest in Human Neuroblastoma Cells (인체 신경아세포종에서 cAMP 처리에 의한 pRB의 인산화 억제 및 p21WAF1/CIP1의 유도)

  • Park, Yung-Hyun;Lee, Sang-Hyeon
    • Journal of Life Science
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    • v.13 no.5
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    • pp.642-650
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    • 2003
  • To develop a new approach to the treatment of neuroblastoma cells we evaluated the effect of cAMP on the Ewing's sarcoma cell line CHP-100. We observed that the proliferation-inhibitory effect of cAMP analogs was due to cell cycle arrest and induction of apoptosis, which was confirmed by observing the morphological changes and DNA fragmentation. DNA flow cytometric analysis revealed that cAMP arrested the cell cycle progression at the G1 phase, which effects were associated with inhibition of phosphorylation of retinoblastoma protein (pRB) and enhanced binding of pRB and the transcription factor E2F-1. cAMP also suppressed the cyclin-dependent kinase (Cdk) 2 and cyclin E-associated kinase activity without changes of their expressions. Furthermore, cAMP induced the levels of Cdk inhibitor $p21^{WAF1/CIP1$ expression and p21 proteins induced by cAMP were associated with Cdk2. Overall, our results identify a combined mechanism involving the inhibition of pRB phosphorylation and induction of p21 as targets for cAMP, and this may explain some of its anti-cancer effects.

Relation of Poly(ADP-ribose) Polymerase Cleavage and Apoptosis Induced by Paclitaxel in HeLa S3 Uterine Cancer Cells (HeLa S3 자궁암 세포에서 paclitaxel 에 의해 유도된 Poly(ADP-ribose) Polymerase 분철과 세포자멸사와의 관계)

  • Chang, Jeong-Hyun;Kim, Kwang-Youn;Ahn, Soon-Cheol;Kwon, Heun-Young
    • Journal of Life Science
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    • v.17 no.8 s.88
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    • pp.1027-1033
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    • 2007
  • Although paclitaxel induces apoptosis of cancer cells, its exact mechanism of action is not yet known. The present study has been performed to determine whether influence of paclitaxel in HeLa $S_{3}$ uterine cancer cells. Three assays were employed in this study: cell cytotoxicity, morphological assessments of apoptotic cells (DAPI staining assay), and western blot analysis. The results indicated that paclitaxel has cytotoxic effects in HeLa $S_{3}$ cells. Especially, the $IC_{50}$ value of paclitaxel was about 1 ${\mu}M$. And morphological changes (fragmentation) of cells were observed by paclitaxel in HeLa $S_{3}$ cells. The flow cytometric analysis of paclitaxel-treated cells indicated a block of G2/M phase. The results that pacli-taxel regulates the cell cycle, especially Sub-$G_{1}$ phase. Paclitaxel induces apoptosis of HeLa $S_{3}$ cells via PARP-dependent fashion, and this apoptosis is related to disappearance of Bcl-2 proteins.

Apoptosis and Peripheral Benzodiazepin Receptor (PBR) Expression in Human Granulosa-Luteal Cells by GnRH-agonist (GnRH-agonist에 의한 인간 과립-황체화 세포의 세포사멸과 PBR 단백질의 발현)

  • Kim, Sei-Kwang;Youm, Yun-Hee;Yoon, Jeong-Mi;Bai, Sang-Wook;Yang, Hyun-Won;Cho, Dong-Jae;Yoon, Yong-Dal;Song, Chan-Ho
    • Clinical and Experimental Reproductive Medicine
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    • v.31 no.2
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    • pp.83-94
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    • 2004
  • Objective: To investigate whether GnRH-agonist (GnRH-Ag) using in IVF-ET affects apoptosis of human granulosa-luteal cells and expression of peripheral benzodiazepine receptor (PBR) protein involved in the apoptosis of the cells. Methods: Granulosa-luteal cells obtained during oocyte retrieval were cultured and treated with $10^{-5}M$ GnRH-Ag. Apoptosis of the cells by the treatment was confirmed using DNA fragmentation analysis 24 h after culture. The presence of PBR protein within the cells was examined by immunofluorescence staining and the expression of the protein was analyzed by Western blotting. In addition, it was measured for progesterone and nitric oxide (NO) produced by granulosa-luteal cells after GnRH-Ag treatment. To evaluate the relationship between NO production and PBR expression, sodium nitroprusside (SNP) as a NO donor was added in media and investigated the expression of PBR protein by Western blotting. Results: Apoptosis increased in the granulosa-luteal cells 24 h after GnRH-Ag treatment, whereas the expression of PBR protein significantly decreased. Furthermore, the production of progesterone and nitric oxide (NO) by the cells significantly fell from 12 h after the treatment. In the results of Western blotting after SNP treatment, the expression of PBR protein increased in the treatment with SNP alone to the granulosa-luteal cells, but was suppressed in the treatment with GnRH-Ag and SNP. Additionally, the staining result of PBR protein in the cells showed the even distribution of it through the cell. Conclusion: These results demonstrate that GnRH-Ag treatment induces apoptosis, decreasing expression of PBR protein and NO production in human granulosa-luteal cells. The present study suggests that one of the apoptosis mechanism of human granulosa-luteal cells by GnRH-Ag might be a signal transduction pathway via NO and PBR.