• Title/Summary/Keyword: BAX

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Apoptosis-Induced Effects of Extract from Artemisia annua Linné by Modulating Akt/mTOR/GSK-3β Signal Pathway in AGS Human Gastric Carcinoma Cells (AGS 인체 위암 세포에서 Akt/mTOR/GSK-3β 신호경로 조절을 통한 개똥쑥 추출물의 Apoptosis 유도 효과)

  • Kim, Eun Ji;Kim, Guen Tae;Kim, Bo Min;Lim, Eun Gyeong;Kim, Sang-Yong;Kim, Young Min
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.45 no.9
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    • pp.1257-1264
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    • 2016
  • Extracts from Artemisia annua $Linn\acute{e}$ (AAE) have various functions (anti-malaria, anti-virus, and anti-oxidant). However, the mechanism of the effects of AAE is not well known. Thus, we determined the apoptotic effects of AAE in AGS human gastric carcinoma cells. In this study, we suggested that AAE may exert cancer cell apoptosis through the Akt/mammalian target of rapamycin (mTOR)/glycogen synthase kinase (GSK)-$3{\beta}$ signal pathway and mitochondria-mediated apoptotic proteins. Activation by Akt phosphorylation resulted in cell proliferation through phosphorylation of tuberous sclerosis complex 2 (TSC2), mTOR, and GSK-$3{\beta}$. Thus, de-phosphorylation of Akt inhibited cell proliferation and induced apoptosis through inhibition of Akt, mTOR, phosphorylation of GSK-$3{\beta}$ at serine9, and control of Bcl-2 family members. Inhibition of GSK-$3{\beta}$ attenuated loss of mitochondrial membrane potential and release of cytochrome C. Bax and pro-apoptotic proteins were activated by their translocation into mitochondria from the cytosol. Translocation of Bax induced outer membrane transmission and generated apoptosis through cytochrome C release and caspase activity. We also measured 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, lactate dehydrogenase assay, Hoechst 33342 staining, Annexin V-PI staining, 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethyl-imidacarbocyanine iodide staining, and Western blotting. Accordingly, our study showed that AAE treatment to AGS cells resulted in inhibition of Akt, TSC2, GSK-$3{\beta}$-phosphorylated, Bim, Bcl-2, and pro-caspase 3 as well as activation of Bax and Bak expression. These results indicate that AAE induced apoptosis via a mitochondrial event through regulation of the Akt/mTOR/GSK-$3{\beta}$ signaling pathways.

The Signaling of UV-induced Apoptosis in Melanocytes

  • Kim, Dong-Seok;Kim, Sook--Young;Park, Kyoung-Chan
    • Journal of Photoscience
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    • v.9 no.2
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    • pp.217-220
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    • 2002
  • Ultraviolet B (UVB) radiation may activate or deteriorate cultured human epidermal melanocytes, depending on the doses and culture conditions. In this study, we examined whether apoptosis of melanocytes can be induced by physiologic doses of UVB irradiation. PI staining for DNA condensation and flow cytometric analyses demonstrated the apoptotic cell death of melanocytes after UVB irradiation. The level of p53 and Bax revealed a dose-dependent increase with increasing dose of UVB, but the level of Bcl-2 remained unchanged. Confocal microscopic examination showed that Bax moved trom a diffuse to a punctate distribution after UVB irradiation. However, there were no changes in the pattern of Bcl-2. We next examined the downstream targets of apoptosis. Our results showed that a precursor form of caspase-3 disappeared with increasing doses of UVB. We also observed cleavage of poly(ADP-ribose) polymerase (PARP) after UVB irradiation. In addition, UVB irradiation resulted in a remarkable activation of c-Jun N-terminal kinase (JNK). These results indicate that UVB may induce apoptosis via JNK activation in human melanocytes.

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Activation of apoptotic protein in U937 cells by a component of turmeric oil

  • Lee, Yong-Kyu
    • BMB Reports
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    • v.42 no.2
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    • pp.96-100
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    • 2009
  • Aromatic (ar)-turmerone from turmeric oil displays anti-tumorigenesis activity that includes inhibited cell proliferation. This study investigated ar-turmerone-mediated apoptotic protein activation in human lymphoma U937 cells. Ar-turmerone treatment inhibited U937 cell viability in a concentration-dependent fashion, with inhibition exceeding 84%. Moreover, the treatment produced nucleosomal DNA fragmentation and the percentage of sub-diploid cells increased in a concentration-dependent manner; both are hallmarks of apoptosis. The apoptotic effect of ar-turmerone was associated with the induction of Bax and p53 proteins, rather than Bcl-2 and p21. Activation of mitochondrial cytochrome c and caspase-3 demonstrated that the activation of caspases accompanied the apoptotic effect of ar-turmerone, which mediated cell death. These results suggest that the apoptotic effect of ar-turmerone on U937 cells may involve caspase-3 activation through the induction of Bax and p53, rather than Bcl-2 and p21.

Effects of Curcumin on Apoptosis in SW480 Human Colon Cancer Cell Line (Curcumin이 인체대장암세포주인 SW480 cell에서 세포사멸에 미치는 영향)

  • 최옥숙;김우경
    • Journal of Nutrition and Health
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    • v.37 no.1
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    • pp.31-37
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    • 2004
  • Curcumin, a natural compound extracted from rhizomes of Curcuma longa, has been shown to possess potent anti-inflammatory and anti-tumor activity. The mechanism by which curcumin initiates apoptosis remains poorly understood. In this study, we investigated the effects of curcumin on caspase-3 activity and protein expression of procaspase-3, Bcl-2, Bax, total Akt and phosphorylated Akt in SW480 human colon cancer cell. We cultured SW480 cells in the presence of various concentrations (0, 10, 20 or 30 uM) of curcumin. Curcumin inhibited colon cancer cell growth in a dose-dependent manner (p < 0.05). Caspase-3 activity was significantly increased dose-dependently in cells treated with curcumin (p < 0.05), concisely procaspase-3 expression was significantly decreased. Bcl-2 levels were decreased dose-dependently in cells treated with curcumin (p < 0.05), but Ben remained unchanged. In addition, phosphorylated Akt levels and total Akt levels were markedly lower in cells treated with 20 uM of curcumin treatment (p < 0.05), In conclusion, we have shown that curcumin inhibits cell growth and induces apoptosis in SW480 human colon cancer cell lines via Akt signal pathway.

Compound K, Ginseng Saponin Metabolite, Induces Apoptosis in Human Monocytic Leukemia cells

  • Kang, Kyong-Ah;Kim, Dong-Hyun;Hyun, Jin-Won
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 2003.11a
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    • pp.75-75
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    • 2003
  • We report upon the cytotoxic activity of the ginseng saponin metabolite, Compound K (20-O-D-glucopyranosyl-20(S)-protopanaxadiol, IH90l) on various human leukemia cell lines. Compound K had most effect on U937, a human monocytic leukemia cell line, which on treatment showed; a exposure of phosphatidylserine from the inner cell membrane to the outer cell membrane, the formation of apoptotic bodies and DNA fragmentation, - characteristics of apoptosis. Compound K induced apoptosis by up-regulating Bax, disrupting the mitochondria membrane potential, and by activating caspase 9 and caspase 3. Therefore, we suggest that Compound K inhibit U937 cell growth by inducing apoptosis through the up-regulation of Bax and caspase activation.

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In vitro Investigation of Cytotoxic and Apoptotic Effects of Cynara L. Species in Colorectal Cancer Cells

  • Simsek, Ela Nur;Uysal, Tuna
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.11
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    • pp.6791-6795
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    • 2013
  • Apoptotic and cytotoxic activity of plant extracts obtaining from naturally growing Cynara syriaca in Turkey and cultivated C cardunculus against DLD1 colorectal cancer cells was determined. Extracts from wild and cultivated Cynara species were obtained from their vegetative parts and receptacles using hexane and applied with five different dose (0.1-1 mg/ml) as well as apigenin for MTT tests for three time periods (24, 48 and 72 hours). After cells were treated with $IC_{50}$ doses for each extract total DNA and RNA were isolated for determination of the cause of cell death. From isolated RNAs, cDNA were synthesized and amplification of p21, BCL-2 and BAX gene regions was carried out. Consequently, we found that pro-apoptotic (BAX) gene expression and a cell cycle inhibitor (p21) were induced in the presence of our artichoke extracts. In contrast, anti-apoptotic BCL-2 gene expression was reduced compared to the control group. In addition DNA fragmentation results demonstrated DLD1 cell death via apoptosis.

Immunohistochemical Changes of Apoptotic Control Genes by Chronic Inhibition of Nitric Oxide in Rats

  • Bae, Hyung-Joon
    • Biomedical Science Letters
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    • v.18 no.4
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    • pp.420-427
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    • 2012
  • Sprague-Dawley (SD) rats were orally administered with NG-nitro-L-arginine methyl ester (L-NAME), which inhibits or blocks the production of nitric oxide from L-arginine in vascular endothelial cells and vessel tissue. We examined the effects of nitric oxide on some physiological changes such as blood pressure and heart rate, and confirms the apoptosis induced by the suppressed nitric oxide activity in the kidney. This study was performed to investigate correlation between the activities of nitric oxide and apoptosis by immunohistochemical changes of apoptotic control proteins with regulated chronic inhibition of nitric oxide. In the kidney from L-NAME-treated group, immunohistochemical reaction to the antigens of apoptosis inhibiting proteins such as bcl-2 and bcl-xL, exhibited a time-dependent reduction. The expression of apoptosis-inhibiting proteins such as bax and p53 increased expression in proportion to the duration of treatment. The most sensitive apoptosis regulating proteins to L-NAME were p53 in stimulation and bcl-2 in inhibition, respectively.

Identification of Inhibitors Against BAK Pore Formation using an Improved in vitro Assay System

  • Song, Seong-Soo;Lee, Won-Kyu;Aluvila, Sreevidya;Oh, Kyoung Joon;Yu, Yeon Gyu
    • Bulletin of the Korean Chemical Society
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    • v.35 no.2
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    • pp.419-424
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    • 2014
  • The pro-apoptotic BCL-2 family protein BID activates BAK and/or BAX, which form oligomeric pores in the mitochondrial outer membrane. This results in the release of cytochrome c into the cytoplasm, initiating the apoptotic cascade. Here, we utilized liposomes encapsulating sulfo-rhodamine at a controlled temperature to improve upon a previously reported assay system with enhanced sensitivity and specificity for measuring membrane permeabilization by BID-dependent BAK activation. BAK activation was inhibited by BCL-$X_L$ protein but not by a mutant protein with impaired anti-apoptotic activity. With the assay system, we screened a chemical library and identified several compounds including trifluoperazine, a mitochondrial apoptosis-induced channel blocker. It inhibited BAK activation by direct binding to BAK and blocking the oligomerization of BAK.

Modulations of Bcl-2/Bax Families were Involved in The Chemopreventive Effects of Licorice Root in Mcf-7 Human Breast Cancer Cell

  • Jo, Eun-Hye;Hong, Hee-Do;Kim, Sung-Hun;Lee, Yong-Soon;Kang, Kyung-Sun
    • Proceedings of the Korean Society of Toxicology Conference
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    • 2003.10b
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    • pp.111-111
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    • 2003
  • Recently, cancer chemoprevention with strategies using foods and medicinal herbs has been regarded as one of the most visible fields for cancer control. The genistein in soy, the American ginseng and the resveratrol in a grape are well known as that has antiproliferative properties in human breast cancer.(omitted)

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