WorldWideScience

Sample records for acid induces apoptosis

  1. Metformin protects rat hepatocytes against bile acid-induced apoptosis.

    Titia E Woudenberg-Vrenken

    Full Text Available BACKGROUND: Metformin is used in the treatment of Diabetes Mellitus type II and improves liver function in patients with non-alcoholic fatty liver disease (NAFLD. Metformin activates AMP-activated protein kinase (AMPK, the cellular energy sensor that is sensitive to changes in the AMP/ATP-ratio. AMPK is an inhibitor of mammalian target of rapamycin (mTOR. Both AMPK and mTOR are able to modulate cell death. AIM: To evaluate the effects of metformin on hepatocyte cell death. METHODS: Apoptotic cell death was induced in primary rat hepatocytes using either the bile acid glycochenodeoxycholic acid (GCDCA or TNFα in combination with actinomycin D (actD. AMPK, mTOR and phosphoinositide-3 kinase (PI3K/Akt were inhibited using pharmacological inhibitors. Apoptosis and necrosis were quantified by caspase activation, acridine orange staining and Sytox green staining respectively. RESULTS: Metformin dose-dependently reduces GCDCA-induced apoptosis, even when added 2 hours after GCDCA, without increasing necrotic cell death. Metformin does not protect against TNFα/ActD-induced apoptosis. The protective effect of metformin is dependent on an intact PI3-kinase/Akt pathway, but does not require AMPK/mTOR-signaling. Metformin does not inhibit NF-κB activation. CONCLUSION: Metformin protects against bile acid-induced apoptosis and could be considered in the treatment of chronic liver diseases accompanied by inflammation.

  2. Dihydrolipoic Acid Induces Cytotoxicity in Mouse Blastocysts through Apoptosis Processes

    Wen-Hsiung Chan

    2012-03-01

    Full Text Available α-Lipoic acid (LA is a thiol with antioxidant properties that protects against oxidative stress-induced apoptosis. LA is absorbed from the diet, taken up by cells and tissues, and subsequently reduced to dihydrolipoic acid (DHLA. In view of the recent application of DHLA as a hydrophilic nanomaterial preparation, determination of its biosafety profile is essential. In the current study, we examined the cytotoxic effects of DHLA on mouse embryos at the blastocyst stage, subsequent embryonic attachment and outgrowth in vitro, in vivo implantation by embryo transfer, and early embryonic development in an animal model. Blastocysts treated with 50 μM DHLA exhibited significantly increased apoptosis and a corresponding decrease in total cell number. Notably, the implantation success rates of blastocysts pretreated with DHLA were lower than that of their control counterparts. Moreover, in vitro treatment with 50 μM DHLA was associated with increased resorption of post-implantation embryos and decreased fetal weight. Data obtained using an in vivo mouse model further disclosed that consumption of drinking water containing 100 μM DHLA led to decreased early embryo development, specifically, inhibition of development to the blastocyst stage. However, it appears that concentrations of DHLA lower than 50 μM do not exert a hazardous effect on embryonic development. Our results collectively indicate that in vitro and in vivo exposure to concentrations of DHLA higher than 50 μM DHLA induces apoptosis and retards early pre- and post-implantation development, and support the potential of DHLA to induce embryonic cytotoxicity.

  3. Aminomethylphosphonic Acid and Methoxyacetic Acid Induce Apoptosis in Prostate Cancer Cells

    Keshab R. Parajuli

    2015-05-01

    Full Text Available Aminomethylphosphonic acid (AMPA and its parent compound herbicide glyphosate are analogs to glycine, which have been reported to inhibit proliferation and promote apoptosis of cancer cells, but not normal cells. Methoxyacetic acid (MAA is the active metabolite of ester phthalates widely used in industry as gelling, viscosity and stabilizer; its exposure is associated with developmental and reproductive toxicities in both rodents and humans. MAA has been reported to suppress prostate cancer cell growth by inducing growth arrest and apoptosis. However, it is unknown whether AMPA and MAA can inhibit cancer cell growth. In this study, we found that AMPA and MAA inhibited cell growth in prostate cancer cell lines (LNCaP, C4-2B, PC-3 and DU-145 through induction of apoptosis and cell cycle arrest at the G1 phase. Importantly, the AMPA-induced apoptosis was potentiated with the addition of MAA, which was due to downregulation of the anti-apoptotic gene baculoviral inhibitor of apoptosis protein repeat containing 2 (BIRC2, leading to activation of caspases 7 and 3. These results demonstrate that the combination of AMPA and MAA can promote the apoptosis of prostate cancer cells, suggesting that they can be used as potential therapeutic drugs in the treatment of prostate cancer.

  4. Anacardic acid induces apoptosis-like cell death in the rice blast fungus Magnaporthe oryzae.

    Muzaffar, Suhail; Bose, Chinchu; Banerji, Ashok; Nair, Bipin G; Chattoo, Bharat B

    2016-01-01

    Anacardic acid (6-pentadecylsalicylic acid), extracted from cashew nut shell liquid, is a natural phenolic lipid well known for its strong antibacterial, antioxidant, and anticancer activities. Its effect has been well studied in bacterial and mammalian systems but remains largely unexplored in fungi. The present study identifies antifungal, cytotoxic, and antioxidant activities of anacardic acid in the rice blast fungus Magnaporthe oryzae. It was found that anacardic acid causes inhibition of conidial germination and mycelial growth in this ascomycetous fungus. Phosphatidylserine externalization, chromatin condensation, DNA degradation, and loss of mitochondrial membrane potential suggest that growth inhibition of fungus is mainly caused by apoptosis-like cell death. Broad-spectrum caspase inhibitor Z-VAD-FMK treatment indicated that anacardic acid induces caspase-independent apoptosis in M. oryzae. Expression of a predicted ortholog of apoptosis-inducing factor (AIF) was upregulated during the process of apoptosis, suggesting the possibility of mitochondria dependent apoptosis via activation of apoptosis-inducing factor. Anacardic acid treatment leads to decrease in reactive oxygen species rather than increase in reactive oxygen species (ROS) accumulation normally observed during apoptosis, confirming the antioxidant properties of anacardic acid as suggested by earlier reports. Our study also shows that anacardic acid renders the fungus highly sensitive to DNA damaging agents like ethyl methanesulfonate (EMS). Treatment of rice leaves with anacardic acid prevents M. oryzae from infecting the plant without affecting the leaf, suggesting that anacardic acid can be an effective antifungal agent. PMID:26381667

  5. CD36 Mediated Fatty Acid-Induced Podocyte Apoptosis via Oxidative Stress.

    Wei Hua

    Full Text Available Hyperlipidemia-induced apoptosis mediated by fatty acid translocase CD36 is associated with increased uptake of ox-LDL or fatty acid in macrophages, hepatocytes and proximal tubular epithelial cells, leading to atherosclerosis, liver damage and fibrosis in obese patients, and diabetic nephropathy (DN, respectively. However, the specific role of CD36 in podocyte apoptosis in DN with hyperlipidemia remains poorly investigated.The expression of CD36 was measured in paraffin-embedded kidney tissue samples (Ctr = 18, DN = 20 by immunohistochemistry and immunofluorescence staining. We cultured conditionally immortalized mouse podocytes (MPC5 and treated cells with palmitic acid, and measured CD36 expression by real-time PCR, Western blot analysis and immunofluorescence; lipid uptake by Oil red O staining and BODIPY staining; apoptosis by flow cytometry assay, TUNEL assay and Western blot analysis; and ROS production by DCFH-DA fluorescence staining. All statistical analyses were performed using SPSS 21.0 statistical software.CD36 expression was increased in kidney tissue from DN patients with hyperlipidemia. Palmitic acid upregulated CD36 expression and promoted its translocation from cytoplasm to plasma membrane in podocytes. Furthermore, palmitic acid increased lipid uptake, ROS production and apoptosis in podocytes, Sulfo-N-succinimidyloleate (SSO, the specific inhibitor of the fatty acid binding site on CD36, decreased palmitic acid-induced fatty acid accumulation, ROS production, and apoptosis in podocytes. Antioxidant 4-hydroxy-2,2,6,6- tetramethylpiperidine -1-oxyl (tempol inhibited the overproduction of ROS and apoptosis in podocytes induced by palmitic acid.CD36 mediated fatty acid-induced podocyte apoptosis via oxidative stress might participate in the process of DN.

  6. Apoptosis of Human Pancreatic Carcinoma Cells Induced By All-Trans Retinoic Acid and Interferon

    Xiao-hua Wang; Yuan-qin Yin; Ping Ma; Cheng-guang Sui; Fan-dong Meng; Jiang You-hong

    2009-01-01

    Objective: To investigate the apoptosis of human pancreatic carcinoma PC3 cells induced by the combination of all-trans retinoic acid (ATRA) with interferon alpha (IFN-α). Methods: PC3 cells were treated with ATRA and IFN-α. The inhibitory rate of PC3 cell proliferation was detected using MTT method. Cellular apoptosis was determined with flow cytometry. The percentage of PC3 cell apoptosis was assayed using TUNEL methods. Results: ATRA and IFN-α could inhibit cellular proliferation and induces cellular apoptosis of PC3 cells. The inhibitory effect was stronger when the ATRA and IFN-α were combined as a therapy. Conclusion: ATRA inhibits the proliferation of PC3 cells and induce the apoptosis of PC3 cells. The combination of IFN-α with ATRA may enhance these effects on PC3 cells.

  7. Suberoyl bis-hydroxamic acid induces p53-dependent apoptosis of MCF-7 breast cancer cells

    Zhi-gang ZHUANG; Fei FEI; Ying CHEN; Wei JIN

    2008-01-01

    Aim: To study the effects of suberoyl bis-hydroxamic acid (SBHA), an inhibitor of histone deacetylases, on the apoptosis of MCF-7 breast cancer cells. Meth-ods: Apoptosis in MCF-7 cells induced by SBHA was demonstrated by flow cytometric analysis, morphological observation, and DNA ladder. Mitochondrial membrane potential (△ψm) was measured using the fluorescent probe JC-1. The expressions of p53, p21, Bax, and PUMA were determined using RT-PCR or Western blotting analysis after the MCF-7 cells were treated with SBHA or p53 siRNA. Results: SBHA induced apoptosis in MCF-7 cells. The expressions of p53, p21, Bax, and PUMA were induced, and △ψm collapsed after treatment with SBHA. p53 siRNA abrogated the SBHA-induced apoptosis and the expressions of p53, p21, Bax, and PUMA. Conclusion: The activation of the p53 pathway is involved in SBHA-induced apoptosis in MCF-7 cells.

  8. DECREASED APOPTOSIS DURING CAR-MEDIATED HEPATOPROTECTION AGAINST LITHOCHOLIC ACID-INDUCED LIVER INJURY IN MICE

    Beilke, Lisa D.; Aleksunes, Lauren M.; Olson, Erik R.; Besselsen, David G; Klaassen, Curtis D.; Dvorak, Katerina; Cherrington, Nathan J.

    2009-01-01

    Myeloid cell leukemia-1 (Mcl-1) is an anti-apoptotic protein that is regulated by the constitutive androstane receptor (CAR). Activation of CAR can protect the liver against bile acid-induced toxicity and it may have a role in cell death via apoptosis by altering expression of Bcl-2 family proteins such as myeloid cell leukemia-1 (Mcl-1). Our aim was to determine if activation of CAR reduces hepatocellular apoptosis during cholestasis as a mechanism of hepatoprotection. CAR+/+ (WT) and CAR−/−...

  9. PKCa Agonists Enhance the Protective Effect of Hyaluronic Acid on Nitric Oxide-Induced Apoptosis of Articular Chondrocytes in Vitro

    Jian-lin Zhou

    2013-12-01

    The results may be showed that PKCa regulate the expresion of caspase-3, which contribute to the apoptosis of chondrocytes induced by NO. PKC α agonists enhance the protective effect of hyaluronic acid on nitric oxide-induced articular chondrocytes apoptosis.

  10. Fenretinide-induced apoptosis of Huh-7 hepatocellular carcinoma is retinoic acid receptor β dependent

    Wan Yu-Jui

    2007-12-01

    Full Text Available Abstract Background Retinoids are used to treat several types of cancer; however, their effects on liver cancer have not been fully characterized. To investigate the therapeutic potential of retinoids on hepatocellular carcinoma (HCC, the present study evaluates the apoptotic effect of a panel of natural and synthetic retinoids in three human HCC cell lines as well as explores the underlying mechanisms. Methods Apoptosis was determined by caspase-3 cleavage using western blot, DNA double-strand breaks using TUNEL assay, and phosphatidylserine translocation using flow cytometry analysis. Gene expression of nuclear receptors was assessed by real-time PCR. Transactivation assay and chromatin immunoprecipitation (ChIP were conducted to evaluate the activation of RXRα/RARβ pathway by fenretinide. Knockdown of RARβ mRNA expression was achieved by siRNA transfection. Results Our data revealed that fenretinide effectively induces apoptosis in Huh-7 and Hep3B cells. Gene expression analysis of nuclear receptors revealed that the basal and inducibility of retinoic acid receptor β (RARβ expression positively correlate with the susceptibility of HCC cells to fenretinide treatment. Furthermore, fenretinide transactivates the RXRα/RARβ-mediated pathway and directly increases the transcriptional activity of RARβ. Knockdown of RARβ mRNA expression significantly impairs fenretinide-induced apoptosis in Huh-7 cells. Conclusion Our findings reveal that endogenous expression of retinoids receptor RARβ gene determines the susceptibility of HCC cells to fenretinide-induced apoptosis. Our results also demonstrate fenretinide directly activates RARβ and induces apoptosis in Huh-7 cells in a RARβ-dependent manner. These findings suggest a novel role of RARβ as a tumor suppressor by mediating the signals of certain chemotherapeutic agents.

  11. Decreased apoptosis during CAR-mediated hepatoprotection against lithocholic acid-induced liver injury in mice.

    Beilke, Lisa D; Aleksunes, Lauren M; Olson, Erik R; Besselsen, David G; Klaassen, Curtis D; Dvorak, Katerina; Cherrington, Nathan J

    2009-07-10

    Myeloid cell leukemia-1 (Mcl-1) is an anti-apoptotic protein that is regulated by the constitutive androstane receptor (CAR). Activation of CAR can protect the liver against bile acid-induced toxicity and it may have a role in cell death via apoptosis by altering expression of Bcl-2 family proteins such as myeloid cell leukemia-1 (Mcl-1). Our aim was to determine if activation of CAR reduces hepatocellular apoptosis during cholestasis as a mechanism of hepatoprotection. CAR(+/+) (WT) and CAR(-/-) (CAR-null) mice were pre-treated with compounds known to activate CAR prior to induction of intrahepatic cholestasis using the secondary bile acid lithocholic acid (LCA). Pre-treatment with the CAR activators phenobarbital (PB) and TCPOBOP (TC), as well as the non-CAR activator pregnenolone 16alpha-carbontrile (PCN), protected against LCA-induced liver injury in WT mice, whereas liver injury was more extensive without CAR (CAR-null). Unexpectedly, expression of anti-apoptotic Mcl-1 and Bcl-x(L) was not increased in hepatoprotected mice. Compared to unprotected groups, apoptosis was decreased in hepatoprotected mice as evidenced by the absence of cleaved caspase 3 (cCasp3). In contrast to the cytoplasmic localization in the injured livers (LCA and oltipraz), Mcl-1 protein was localized in the nucleus of hepatoprotected livers to potentially promote cell survival. This study demonstrates that although apoptosis is reduced in hepatoprotected mice pre-treated with CAR and non-CAR activators; hepatoprotection is not directly a result of CAR-induced Mcl-1 expression. PMID:19433268

  12. Gambogic acid inhibits growth, induces apoptosis, and overcomes drug resistance in human colorectal cancer cells.

    Wen, Chuangyu; Huang, Lanlan; Chen, Junxiong; Lin, Mengmeng; Li, Wen; Lu, Biyan; Rutnam, Zina Jeyapalan; Iwamoto, Aikichi; Wang, Zhongyang; Yang, Xiangling; Liu, Huanliang

    2015-11-01

    The emergence of chemoresistance is a major limitation of colorectal cancer (CRC) therapies and novel biologically based therapies are urgently needed. Natural products represent a novel potential anticancer therapy. Gambogic acid (GA), a small molecule derived from Garcinia hanburyi Hook. f., has been demonstrated to be highly cytotoxic to several types of cancer cells and have low toxicity to the hematopoietic system. However, the potential role of GA in colorectal cancer and its ability to overcome the chemotherapeutic resistance in CRC cells have not been well studied. In the present study, we showed that GA directly inhibited proliferation and induced apoptosis in both 5-fluorouracil (5-FU) sensitive and 5-FU resistant colorectal cancer cells; induced apoptosis via activating JNK signaling pathway. The data, therefore, suggested an alternative strategy to overcome 5-FU resistance in CRC and that GA could be a promising medicinal compound for colorectal cancer therapy. PMID:26397804

  13. Heat shock protein 70-dependent protective effect of polaprezinc on acetylsalicylic acid-induced apoptosis of rat intestinal epithelial cells.

    Qin, Ying; Naito, Yuji; Handa, Osamu; Hayashi, Natsuko; Kuki, Aiko; Mizushima, Katsura; Omatsu, Tatsushi; Tanimura, Yuko; Morita, Mayuko; Adachi, Satoko; Fukui, Akifumi; Hirata, Ikuhiro; Kishimoto, Etsuko; Nishikawa, Taichiro; Uchiyama, Kazuhiko; Ishikawa, Takeshi; Takagi, Tomohisa; Yagi, Nobuaki; Kokura, Satoshi; Yoshikawa, Toshikazu

    2011-11-01

    Protection of the small intestine from mucosal injury induced by nonsteroidal anti-inflammatory drugs including acetylsalicylic acid is a critical issue in the field of gastroenterology. Polaprezinc an anti-ulcer drug, consisting of zinc and L-carnosine, provides gastric mucosal protection against various irritants. In this study, we investigated the protective effect of polaprezinc on acetylsalicylic acid-induced apoptosis of the RIE1 rat intestinal epithelial cell line. Confluent rat intestinal epithelial cells were incubated with 70 µM polaprezinc for 24 h, and then stimulated with or without 15 mM acetylsalicylic acid for a further 15 h. Subsequent cellular viability was quantified by fluorometric assay based on cell lysis and staining. Acetylsalicylic acid-induced cell death was also qualified by fluorescent microscopy of Hoechst33342 and propidium iodide. Heat shock proteins 70 protein expression after adding polaprezinc or acetylsalicylic acid was assessed by western blotting. To investigate the role of Heat shock protein 70, Heat shock protein 70-specific small interfering RNA was applied. Cell viability was quantified by fluorometric assay based on cell lysis and staining and apoptosis was analyzed by fluorescence-activated cell sorting. We found that acetylsalicylic acid significantly induced apoptosis of rat intestinal epithelial cells in a dose- and time-dependent manner. Polaprezinc significantly suppressed acetylsalicylic acid-induced apoptosis of rat intestinal epithelial cells at its late phase. At the same time, polaprezinc increased Heat shock protein 70 expressions of rat intestinal epithelial cells in a time-dependent manner. However, in Heat shock protein 70-silenced rat intestinal epithelial cells, polaprezinc could not suppress acetylsalicylic acid -induced apoptosis at its late phase. We conclude that polaprezinc-increased Heat shock protein 70 expression might be an important mechanism by which polaprezinc suppresses acetylsalicylic

  14. Conjugated linoleic acid induces apoptosis through estrogen receptor alpha in human breast tissue

    Conjugated linoleic acid (CLA), a naturally occurring fatty acid found in ruminant products such as milk and beef, has been shown to possess anti-cancer activities in in vivo animal models and in vitro cell culture systems. In human breast cancer, the overall duration of estrogen exposure is the most important risk factor for developing estrogen-responsive breast cancer. Accordingly, it has been suggested that estrogen exposure reduces apoptosis through the up-regulation of the anti-apoptosis protein, Bcl-2. Bcl-2, an anti-apoptotic protein, regulates apoptosis and plays a crucial role in the development and growth regulation of normal and cancerous cells. Our research interest is to examine the effects of CLA on the induction of apoptosis in human breast tissues. The localization of Bcl-2 in both normal and cancerous human breast tissues was determined by immunohistochemical staining and the Bcl-2 protein expression was tested by western blot analysis. Co-culture of epithelial cells and stromal cells was carried out in the presence or absence of CLA to evaluate apoptosis in the context of a cell-cell interaction. The results showed that both normal and cancerous breast tissues were positive for Bcl-2 staining, which was higher overall in mammary ducts but very low in the surrounding stromal compartment. Interestingly, by quantifying the western blot data, basal Bcl-2 protein levels were higher in normal breast epithelial cells than in cancerous epithelial cells. Furthermore, treatment with 17β-estradiol (E2) stimulated growth and up-regulated Bcl-2 expression in estrogen responsive breast epithelial cells; however, these carcinogenic effects were diminished by either CLA or 4-Hydroxytamoxifen (Tam) and were suppressed further by the combination of CLA and Tam. In both one cell type cultured and co-culture systems, CLA induced cell apoptosis in ERα transfected MDA-MB-231 cells but not in the wild type MDA-MB-231 cells. These data, therefore, demonstrate that ER

  15. Glycyrrhetinic Acid Inhibits Cell Growth and Induces Apoptosis in Ovarian Cancer A2780 Cells

    Venus Haghshenas

    2014-10-01

    Full Text Available Purpose: Accumulating evidence indicates that glycyrrhizin (GZ and its hydrolyzed metabolite 18-β glycyrrhetinic acid (GA exhibit anti-inflammatory and anticancer activities. The objective of this study was to examine the in vitro cytotoxic activity of GA on human ovarian cancer A2780 cells. Methods: A2780 cells were cultured in RPMI1640 containing 10% fetal bovine serum. Cells were treated with different doses of GA and cell viability and proliferation were detected by dye exclusion and 3-bis-(2-methoxy-4-nitro-5-sulfophenyl-2H-tetrazolium-5-carboxanilide (XTT assays. Apoptosis induction and expression of Fas and Fas ligand (FasL were analyzed by flow cytometry. Results: We observed that GA decreases cell viability and suppressed cells proliferation in a dose-dependent manner as detected by dye-exclusion and XTT assayes. In addition, our flow cytometry data show that GA not only induces apoptosis in A2780 cells but also upregulates both Fas and FasL on these cells in a dose-dependent manner. Conclusion: we demonstrate that GA causes cell death in A2780 cells by inducing apoptosis.

  16. Resistance to ursodeoxycholic acid-induced growth arrest can also result in resistance to deoxycholic acid-induced apoptosis and increased tumorgenicity

    There is a large body of evidence which suggests that bile acids increase the risk of colon cancer and act as tumor promoters, however, the mechanism(s) of bile acids mediated tumorigenesis is not clear. Previously we showed that deoxycholic acid (DCA), a tumorogenic bile acid, and ursodeoxycholic acid (UDCA), a putative chemopreventive agent, exhibited distinct biological effects, yet appeared to act on some of the same signaling molecules. The present study was carried out to determine whether there is overlap in signaling pathways activated by tumorogenic bile acid DCA and chemopreventive bile acid UDCA. To determine whether there was an overlap in activation of signaling pathways by DCA and UDCA, we mutagenized HCT116 cells and then isolated cell lines resistant to UDCA induced growth arrest. These lines were then tested for their response to DCA induced apoptosis. We found that a majority of the cell lines resistant to UDCA-induced growth arrest were also resistant to DCA-induced apoptosis, implying an overlap in DCA and UDCA mediated signaling. Moreover, the cell lines which were the most resistant to DCA-induced apoptosis also exhibited a greater capacity for anchorage independent growth. We conclude that UDCA and DCA have overlapping signaling activities and that disregulation of these pathways can lead to a more advanced neoplastic phenotype

  17. C. butyricum lipoteichoic acid inhibits the inflammatory response and apoptosis in HT-29 cells induced by S. aureus lipoteichoic acid.

    Wang, Jinbo; Qi, Lili; Mei, Lehe; Wu, Zhige; Wang, Hengzheng

    2016-07-01

    Lipoteichoic acid (LTA) is one of microbe-associated molecular pattern (MAMP) molecules of gram-positive bacteria. In this study, we demonstrated that Clostridium butyricum LTA (bLTA) significantly inhibited the inflammatory response and apoptosis induced by Staphylococcus aureus LTA (aLTA) in HT-29 cells. aLTA stimulated the inflammatory responses by activating a strong signal transduction cascade through NF-κB and ERK, but bLTA did not activate the signaling pathway. bLTA pretreatment inhibited the activation of the NF-κB and ERK signaling pathway induced by aLTA. The expression and release of cytokines such as IL-8 and TNF-α were also suppressed by bLTA pretreatment. aLTA treatment induced apoptosis in HT-29 cells, but bLTA did not affect the viability of the cells. Further study indicated that bLTA inhibited apoptosis in HT-29 cells induced by aLTA. These results suggest that bLTA may act as an aLTA antagonist and that an antagonistic bLTA may be a useful agent for suppressing the pro-inflammatory activities of gram-positive pathogenic bacteria. PMID:27020942

  18. Perfluorononanoic acid-induced apoptosis in rat spleen involves oxidative stress and the activation of caspase-independent death pathway

    Perfluoroalkyl acid (PFAA)-induced apoptosis has been reported in many cell types. However, minimal information on its mode of action is available. This study explored the possible involvement of apoptotic signaling pathways in a nine-carbon-chain length PFAA-perfluorononanoic acid (PFNA)-induced splenocyte apoptosis. After a 14-day exposure to PFNA, rat spleens showed dose-dependent levels of apoptosis. The production of pro-inflammatory and anti-inflammatory cytokines was significantly increased and decreased, respectively. However, protein levels of tumor necrosis factor receptor 1 (TNFR1), fas-associated protein with death domain (FADD), caspase 8 and caspase 3, which are involved in inflammation-related and caspase-dependent apoptosis, were discordant. Peroxisome proliferator-activated receptors alpha (PPARα) and PPARγ genes expression was up-regulated in rats treated with 3 or 5 mg/kg/day of PFNA, and the level of hydrogen peroxide (H2O2) increased concurrently in rats treated with the highest dose. Moreover, superoxide dismutase (SOD) activity and Bcl-2 protein levels were dramatically decreased in spleens after treatment with 3 and 5 mg/kg/day of PFNA. However, protein levels of Bax were unchanged. Apoptosis-inducing factor (AIF), an initiator of caspase-independent apoptosis, was significantly increased in all PFNA-dosed rats. Thus, oxidative stress and the activation of a caspase-independent apoptotic signaling pathway contributed to PFNA-induced apoptosis in rat splenocytes.

  19. Heat shock protein 70-dependent protective effect of polaprezinc on acetylsalicylic acid-induced apoptosis of rat intestinal epithelial cells

    Qin, Ying; NAITO, Yuji; Handa, Osamu; Hayashi, Natsuko; Kuki, Aiko; Mizushima, Katsura; Omatsu, Tatsushi; Tanimura, Yuko; Morita, Mayuko; Adachi, Satoko; Fukui, Akifumi; Hirata, Ikuhiro; Kishimoto, Etsuko; Nishikawa, Taichiro; Uchiyama, Kazuhiko

    2011-01-01

    Protection of the small intestine from mucosal injury induced by nonsteroidal anti-inflammatory drugs including acetylsalicylic acid is a critical issue in the field of gastroenterology. Polaprezinc an anti-ulcer drug, consisting of zinc and L-carnosine, provides gastric mucosal protection against various irritants. In this study, we investigated the protective effect of polaprezinc on acetylsalicylic acid-induced apoptosis of the RIE1 rat intestinal epithelial cell line. Confluent rat intest...

  20. Docosahexaenoic Acid Induces Oxidative DNA Damage and Apoptosis, and Enhances the Chemosensitivity of Cancer Cells

    Eun Ah Song

    2016-08-01

    Full Text Available The human diet contains low amounts of ω-3 polyunsaturated fatty acids (PUFAs and high amounts of ω-6 PUFAs, which has been reported to contribute to the incidence of cancer. Epidemiological studies have shown that a high consumption of fish oil or ω-3 PUFAs reduced the risk of colon, pancreatic, and endometrial cancers. The ω-3 PUFA, docosahexaenoic acid (DHA, shows anticancer activity by inducing apoptosis of some human cancer cells without toxicity against normal cells. DHA induces oxidative stress and oxidative DNA adduct formation by depleting intracellular glutathione (GSH and decreasing the mitochondrial function of cancer cells. Oxidative DNA damage and DNA strand breaks activate DNA damage responses to repair the damaged DNA. However, excessive DNA damage beyond the capacity of the DNA repair processes may initiate apoptotic signaling pathways and cell cycle arrest in cancer cells. DHA shows a variable inhibitory effect on cancer cell growth depending on the cells’ molecular properties and degree of malignancy. It has been shown to affect DNA repair processes including DNA-dependent protein kinases and mismatch repair in cancer cells. Moreover, DHA enhanced the efficacy of anticancer drugs by increasing drug uptake and suppressing survival pathways in cancer cells. In this review, DHA-induced oxidative DNA damage, apoptotic signaling, and enhancement of chemosensitivity in cancer cells will be discussed based on recent studies.

  1. Fatty acid esters of phloridzin induce apoptosis of human liver cancer cells through altered gene expression.

    Sandhya V G Nair

    Full Text Available Phloridzin (phlorizin or phloretin 2'-O-glucoside is known for blocking intestinal glucose absorption. We have investigated the anticarcinogenic effect of phloridzin and its novel derivatives using human cancer cell lines. We have synthesised novel acylated derivatives of phloridzin with six different long chain fatty acids by regioselective enzymatic acylation using Candida Antarctica lipase B. The antiproliferative effects of the new compounds were investigated in comparison with the parent compounds, phloridzin, aglycone phloretin, the six free fatty acids and chemotherapeutic drugs (sorafenib, doxorubicin and daunorubicin using human hepatocellular carcinoma HepG2 cells, human breast adenocarcinoma MDA-MB-231 cells and acute monocytic leukemia THP-1 cells along with normal human and rat hepatocytes. The fatty acid esters of phloridzin inhibited significantly the growth of the two carcinoma and leukemia cells while similar treatment doses were not toxic to normal human or rat hepatocytes. The antiproliferative potency of fatty esters of phloridzin was comparable to the potency of the chemotherapeutic drugs. The fatty acid esters of phloridzin inhibited DNA topoisomerases IIα activity that might induce G0/G1 phase arrest, induced apoptosis via activation of caspase-3, and decreased ATP level and mitochondrial membrane potential in HepG2 cells. Based on the high selectivity on cancer cells, decosahexaenoic acid (DHA ester of phloridzin was selected for gene expression analysis using RT2PCR human cancer drug target array. Antiproliferative effect of DHA ester of phloridzin could be related to the down regulation of anti-apoptotic gene (BCL2, growth factor receptors (EBFR family, IGF1R/IGF2, PDGFR and its downstream signalling partners (PI3k/AKT/mTOR, Ras/Raf/MAPK, cell cycle machinery (CDKs, TERT, TOP2A, TOP2B as well as epigenetics regulators (HDACs. These results suggest that fatty esters of phloridzin have potential chemotherapeutic effects

  2. Oxidative stress-driven mechanisms of nordihydroguaiaretic acid-induced apoptosis in FL5.12 cells

    Nordihydroguaiaretic acid (NDGA), a general lipoxygenase (LOX) enzyme inhibitor, induces apoptosis independently of its activity as a LOX inhibitor in murine pro-B lymphocytes (FL.12 cells) by a mechanism that is still not fully understood. Glutathione depletion, oxidative processes and mitochondrial depolarization appear to contribute to the apoptosis induced by NDGA. The current data demonstrate that NDGA (20 μM)-induced apoptosis in FL5.12 cells is partially protected by N-acetylcysteine (NAC) (10 mM) and dithiothreitol (DTT) (500 μM) pretreatment, confirming a role for oxidative processes. In addition, the treatment of FL5.12 cells with NDGA led to an increase in phosphorylation and activation of the MAP kinases ERK, JNK and p38. Although pretreatment with ERK inhibitors (PD98059 or U0126) abolished ERK phosphorylation in response to NDGA, neither inhibitor had any effect on NDGA-induced apoptosis. SP600125, a JNK inhibitor, did not have any effect on NDGA-induced phosphorylation of JNK nor apoptosis. Pretreatment with the p38 inhibitor SB202190 attenuated NDGA-induced apoptosis by 30% and also abolished p38 phosphorylation, compared to NDGA treatment alone. NAC, but not DTT, also decreased the phosphorylation of p38 and JNK supporting a role for oxidative processes in activating these kinases. Neither NAC nor DTT blocked the phosphorylation of ERK suggesting that this activation is not related to oxidative stress. The release of cytochrome c and activation of caspase-3 induced by NDGA were inhibited by NAC. SB202190 slightly attenuated caspase-3 activation and had no effect on the release of cytochrome c. These data suggest that several independent mechanisms, including oxidative reactions, activation of p38 kinase and cytochrome c release contribute to NDGA-induced apoptosis

  3. Effect of retinoic acid on DNA damage-induced apoptosis in lymphoid cells

    2008-01-01

    Conventional cancer therapy, such as ã-irradiation and cytotoxic drugs, acts via DNA damage-induced apoptosis and inhibition of proliferation. Major problems with conventional cancer therapy are that only subgroups of patients respond favourably to a given treatment, and that side effects often limit the dose efficiency of the treatment. The immune cells of the patient may for instance commit to apoptosis as a result of the therapy. It is therefore a constant search for modulators of DNA dama...

  4. Ursolic Acid Simultaneously Targets Multiple Signaling Pathways to Suppress Proliferation and Induce Apoptosis in Colon Cancer Cells

    Jingshu Wang; Liqun Liu; Huijuan Qiu; Xiaohong Zhang; Wei Guo; Wangbing Chen; Yun Tian; Lingyi Fu; Dingbo Shi; Jianding Cheng; Wenlin Huang; Wuguo Deng

    2013-01-01

    Ursolic acid (UA), a natural pentacyclic triterpenoid carboxylic acid distributed in medical herbs, exerts antitumor effects and is emerging as a promising compound for cancer prevention and therapy, but its excise mechanisms of action in colon cancer cells remains largely unknown. Here, we identified the molecular mechanisms by which UA inhibited cell proliferation and induced apoptosis in human colon cancer SW480 and LoVo cells. Treatment with UA led to significant inhibitions in cell viabi...

  5. Apoptosis selectively induced in BEL-7402 cells by folic acid-modified magnetic nanoparticles combined with 100 Hz magnetic field

    Wen J

    2014-04-01

    Full Text Available Jian Wen,1 Shulian Jiang,1 Zhiqiang Chen,1 Wei Zhao,1 Yongxiang Yi,1 Ruili Yang,1 Baoan Chen2 1Second Affiliated Hospital of Southeast University, 2Department of Hematology, Zhongda Hospital, Medical School, Southeast University, Nanjing, People's Republic of China Objective: To explore the effect of folic acid-modified magnetic nanoparticles (FA-MNPs combined with a 100 Hz extremely low-frequency electromagnetic field (ELF-EMF on the apoptosis of liver cancer BEL-7402 cells. Materials and methods: MNPs (20 nm were prepared by coprecipitation, and then folic acid was coated onto MNPs to prepare FA-MNPs. BEL-7402 cells and HL7702 cells were selected as liver cancer cells and normal liver cells, respectively. The ELF-EMF was generated from a solenoid coil. Cellular uptake of NPs was determined by inductively coupled plasma atomic emission spectroscopy. A 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide assay was used to evaluate cell inhibition. Apoptosis was analyzed by flow cytometry. Statistical analyses were performed using two-way analysis of variance. Results: FA-MNPs combined with a 100 Hz magnetic field significantly inhibited cell proliferation and induced higher apoptosis compared to either the ELF-EMF alone or FA-MNPs alone. FA-MNPs showed a better apoptosis effect and higher iron uptake in BEL-7402 cells compared to in HL7702 cells. On the basis of the ELF-EMF, higher doses of FA-MNPs brought higher apoptosis and higher iron uptake in either BEL-7402 cells or HL7702 cells. Conclusion: These results suggest that FA-MNPs may induce apoptosis in a cellular iron uptake-dependent manner when combined with an ELF-EMF in BEL-7402 cells.Keywords: extremely low-frequency magnetic field, magnetic nanoparticle, apoptosis, liver cancer, folic acid

  6. Ascorbic acid enhances radiation-induced apoptosis in an HL60 human leukemia cell line

    This study was conducted to examine the utility of the combined use of ascorbic acid (AsA) and radiation in clinical applications. We investigated cell survival, DNA fragmentation, and caspase activation after X-ray irradiation and AsA treatment of human leukemia HL60 cells. The number of living cells decreased after combined X-ray irradiation and AsA treatment (2 Gy+5 mM) in comparison with that after X-ray irradiation (2 Gy) or AsA treatment (5 mM) alone. DNA fragmentation was more in the cells subjected to combined X-ray irradiation and AsA treatment than in those subjected to X-ray irradiation alone. Caspase-3, caspase-8, and caspase-9 were highly activated following combined X-ray irradiation and AsA treatment, but caspase-8 activity was not markedly increased after X-ray irradiation alone. Bax levels in the mitochondrial membrane fractions were increased after AsA treatment alone and after combined X-ray irradiation and AsA treatment. However, there was no apparent increase in the Bax levels after X-ray irradiation treatment alone. Thus, this study confirmed that supplementing X-ray irradiation with AsA treatment results in increased apoptosis in HL60 cells. With regard to the apoptosis-inducing factors, we hypothesized that Bax and caspase-8 were activated after combined X-ray irradiation and AsA treatment compared with either treatment alone. (author)

  7. Growth Inhibition and Apoptosis Induced by Retinoic Acid Combined with Interferon Alpha-2a on Transitional Cell Carcinoma of Bladder

    QIANLi-xin; LIUXun-liang; ZHOUJian-wei; MonicaLiebert; ZOUChang-chun; ZOUChang-ping

    2004-01-01

    To identify new favorable agents and develop novel approaches for the chemoprevention and treatment of superficial bladder cancer and invesligate the effects of combination of relinoids and interferon α-2a on growth inhibition and apoptosis induction in bladder cancer cell lines. Methods: Four bladder cancer cell lines, grade 1 to 3,and two retinoids, all-trans-retinoic acid(ATRA) ,9.cis retinoic acid(9cRA) ,combined with inteferon α-2a(INF),were used in the study.We compared the competence of these agents to inhibit growth, induce apoptosis, affect the exptession of nuclear retinoid receptors, and modulate STAT1 protein. Resu/ts: Most of the bladder cancer cell lines were resistant to the effect of ATRA and 9cRA on growth inhibition and apoptosis induction, even at higher concentration (10-5M).The effects of ATRA and 9c RA on cell growth and apoptosis were enhanced by INF α-2a.Combination of ATRA and IFNa-2a induced ~ and Slat 1 expression in three bladder cancer cell lines, ~: The results demonstrated that INFw2a synergize with the inhibitory effect of ATRA and 9c RA on the growth intn'bition and apoptosis of bladder cancer cells in vitro, which suggested that it has a potenlJal intexest for the trealment of transitimml cell carcinmna of bladder.

  8. Inhibitory effect of polyunsaturated fatty acids on apoptosis induced by etoposide, okadaic acid and AraC in Neuro2a cells

    Tomizawa,Kazuhito

    2007-06-01

    Full Text Available Neuronal apoptosis is involved in neurodegenerative diseases such as Alzheimer's disease and Parkinson.s disease. An efficient means of preventing it remains to be found. Some n-3 polyunsaturated fatty acids (PUFAs such as docosahexaenoic acid (DHA, 22 : 6n-3 and eicosapentaenoic acid (EPA, 20 : 5n-3 have been reported to be protective against the neuronal apoptosis and neuronal degeneration seen after spinal cord injury (SCI [1]. However, it is unclear which kinds of PUFAs have the most potent ability to inhibit neuronal apoptosis and whether the simultaneous treatment of PUFAs inhibits the apoptosis. In the present study, we compared the abilities of various n-3- and n-6- PUFAs to inhibit the apoptosis induced after the administration of different apoptotic inducers, etoposide, okadaic acid, and AraC, in mouse neuroblastoma cells (Neuro2a. Preincubation with DHA (22 : 6n-3, eicosapentaenoic acid (EPA, 20 : 5n-3, alpha-linolenic acid (alpha-LNA, 18 : 3n-3, linoleic acid (LA, 18 : 2n-6, arachidonic acid (AA, 20 : 4n-3, and gamma-linolenic acid (gamma-LNA, 18 : 3n-6 significantly inhibited caspase-3 activity and LDH leakage but simultaneous treatment with the PUFAs had no effect on the apoptosis of Neuro2a cells. There were no significant differences of the anti-apoptotic eff ect among the PUFAs. These results suggest that PUFAs may not be effective for inhibiting neuronal cell death after acute and chronic neurodegenerative disorders. However, dietary supplementation with PUFAs may be beneficial as a potential means to delay the onset of the diseases and/or their rate of progression.

  9. Glycyrrhizic acid pretreatment prevents sepsis-induced acute kidney injury via suppressing inflammation, apoptosis and oxidative stress.

    Zhao, Hongyu; Liu, Zhenning; Shen, Haitao; Jin, Shuai; Zhang, Shun

    2016-06-15

    Glycyrrhizic acid (GA), an active ingredient in licorice, has multiple pharmacological activities. The aim of our study was to investigate the molecular mechanism involved in the protective effects of GA in lipopolysaccharide (LPS) stimulated rat mesangial cells (HBZY-1) and septic rats. Sepsis model was established by injection of 5mg/kg LPS in rats or incubation with 1μg/ml LPS for 24h in HBZY-1 cells. A variety of molecular biological experiments were carried out to assess the effects of GA on inflammation, apoptosis, and oxidative stress. First we found that GA alleviated sepsis-induced kidney injury in vivo. Furthermore, GA suppressed inflammatory response in vivo and in vitro. Additionally, GA inhibited cell apoptosis and the changes in expressions of apoptosis related proteins induced by LPS. Moreover, GA markedly inhibited oxidative stress induced by LPS via activation of ERK signaling pathway. Finally GA could inhibit the activation of NF-κ B induced by LPS. Our present study indicates that GA has a protective effect against sepsis-induced inflammatory response, apoptosis, and oxidative stress damage, which provides a molecular basis for a new medical treatment of septic acute kidney injury. PMID:27063444

  10. Inhibition of acid-induced apoptosis by targeting ASIC1a mRNA with short hairpin RNA

    Xie-chuan WENG; Jian-quan ZHENG; Qing-e JIN; Xiao-yun MA

    2007-01-01

    Aim: To study the role of acid-sensing ion channel (ASIC) la in the cell death and apoptosis induced by extracellular acid in C6 glioma cells. Methods: The stable ASICla-silenced C6 cell line, built with RNA interference technology, were con-firmed by RT-PCR and Western blot analysis. The cell viability following acid exposure was analyzed with lactate dehydrogenase (LDH) and 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. The apoptotic cells dyed with Annexin-V and propidium iodide were measured with a flow cytometer, while the changes of cell cycle were also assayed. Results: The downregulation of ASIC 1 a proteins by stable transfection of short hairpin RNA decreased the cell death percentage and increased cell viability following acid exposure with LDH and the MTT assay. The rate of apoptosis was lower in the ASIC la-silenced cell line than that in the wild-type C6 cell line. The percentage of sub-G0 cells was lower in the ASICla-silenced C6 cells than that in the wild-type cells. Conclusion: Extracellular acid induced cell death and apoptosis viaASICla mechanisms in the C6 glioma cells.

  11. Protocatechuic Acid Prevents oxLDL-Induced Apoptosis by Activating JNK/Nrf2 Survival Signals in Macrophages

    Rosaria Varì; Beatrice Scazzocchio; Carmela Santangelo; Carmelina Filesi; Fabio Galvano; Massimo D’Archivio; Roberta Masella; Claudio Giovannini

    2015-01-01

    Protocatechuic acid (PCA), one of the main metabolites of complex polyphenols, exerts numerous biological activities including antiapoptotic, anti-inflammatory, and antiatherosclerotic effects. Oxidised LDL have atherogenic properties by damaging arterial wall cells and inducing p53-dependent apoptosis in macrophages. This study was aimed at defining the molecular mechanism responsible for the protective effects of PCA against oxidative and proapoptotic damage exerted by oxLDL in J774 A.1 mac...

  12. PKCzeta protects against UV-C-induced apoptosis by inhibiting acid sphingomyelinase-dependent ceramide production

    Charruyer, Alexandra; Jean, Christine; Colomba, Audrey; Jaffrézou, Jean-Pierre; Quillet-Mary, Anne; Laurent, Guy; Bezombes, Christine

    2007-01-01

    Abstract In a recent study, we described that UV-C irradiation resulted in redox-dependent activation and relocalization of acid sphingomyelinase (A-SMase) to the external surface of raft membrane microdomains, hydrolysis of sphingomyelin (SM) associated to the plasma membrane outer leaflet, ceramide (CER) generation and apoptosis. In the present study, we have investigated the influence of PKC? , an atypical form of PKC on this pathway. This study shows that PKC? overexpression r...

  13. Modulation of the retinoic acid-induced cell apoptosis and differentiation by the human TR4 orphan nuclear receptor

    In our previous studies, the TR4 orphan nuclear receptor (TR4) has been demonstrated to suppress retinoic acid (RA)-induced transactivation via a negative feedback control mechanism and in situ analysis showed that TR4 is extensively expressed in mouse brain, especially in regions where the cells are proliferating. To further study the potential roles of TR4 during cell differentiation, a tetracycline-inducible system with anti-sense TR4 in teratocarcinoma P19 cell lines was generated to analyze the retinoic acid-induced differentiation of these cells. The results indicated that the expression of TR4 reduced by doxycycline anti-sense TR4 would alter the retinoic acid-induced differentiation pathway that results in the changes of cell morphology and cell cycle profile. Unexpectedly, our data further indicated that the RA-induced apoptosis, judging by DNA fragmentation, could also be altered by the induction of anti-sense TR4. Together, these findings provide the first in vivo evidence that an orphan nuclear receptor, such as TR4, may play major roles in the RA-mediated apoptosis or differentiation in P19 cells

  14. Antibody-targeted horseradish peroxidase associated with indole-3-acetic acid induces apoptosis in vitro in hematological malignancies.

    Dalmazzo, Leandro F F; Santana-Lemos, Bárbara A; Jácomo, Rafael H; Garcia, Aglair B; Rego, Eduardo M; da Fonseca, Luiz M; Falcão, Roberto P

    2011-05-01

    Indole-3-acetic acid (IAA), when oxidized by horseradish peroxidase (HRP), is transformed into cytotoxic molecules capable of inducing cell injury. The aim of this study was to test if, by targeting hematopoietic tumors with HRP-conjugated antibodies in association with IAA treatment, there is induction of apoptosis. We used two lineages of hematologic tumors: NB4, derived from acute promyelocytic leukemia (APL) and Granta-519 from mantle cell lymphoma (MCL). We also tested cells from 12 patients with acute myeloid leukemia (AML) and from 10 patients with chronic lymphocytic leukemia (CLL). HRP targeting was performed with anti-CD33 or anti-CD19 antibodies (depending on the origin of the cell), followed by incubation with goat anti-mouse antibody conjugated with HRP. Eight experimental groups were analyzed: control, HRP targeted, HRP targeted and incubated with 1, 5 and 10mM IAA, and cells not HRP targeted but incubated with 1, 5 and 10mM IAA. Apoptosis was analyzed by flow cytometry using annexin V-FITC and propidium iodide labeling. Results showed that apoptosis was dependent on the dose of IAA utilized, the duration of exposure to the prodrug and the origin of the neoplasia. Targeting HRP with antibodies was efficient in activating IAA and inducing apoptosis. PMID:21168913

  15. Reactive oxygen species and autophagy associated apoptosis and limitation of clonogenic survival induced by zoledronic acid in salivary adenoid cystic carcinoma cell line SACC-83.

    Xi-Yuan Ge

    Full Text Available Salivary adenoid cystic carcinoma is an epithelial tumor in the head and neck region. Despite its slow growth, patients with salivary adenoid cystic carcinoma exhibit poor long term survival because of a high rate of distant metastasis. Lung and bone are common distant metastasis sites. Zoledronic acid, a third generation bisphosphonate, has been used for tumor-induced osteolysis due to bone metastasis and has direct antitumor activity in several human neoplasms. Here, we observed that zoledronic acid inhibited salivary adenoid cystic carcinoma cell line SACC-83 xenograft tumor growth in nude mice. In vitro, zoledronic acid induced apoptosis and reduced clonogenic survival in SACC-83. Flow cytometry and western blotting indicated that the cell cycle was arrested at G0/G1. Zoledronic acid treatment upregulated reactive oxygen species as well as the autophagy marker protein LC-3B. Reactive oxygen species scavenger N-acetylcysteine and autophagy antagonist 3-methyladenine decreased zoledronic acid-induced apoptosis and increased clonogenic survival. Silencing of the autophagy related gene Beclin-1 also decreased zoledronic acid-induced apoptosis and inhibition of clonogenic formation. In addition, isobolographic analysis revealed synergistic effects on apoptosis when zoledronic acid and paclitaxel/cisplatin were combined. Taken together, our results suggest that zoledronic acid induced apoptosis and reduced clonogenic survival via upregulation of reactive oxygen species and autophagy in the SACC-83 cell line. Thus, zoledronic acid should be considered a promising drug for the treatment of salivary adenoid cystic carcinoma.

  16. Ursolic acid simultaneously targets multiple signaling pathways to suppress proliferation and induce apoptosis in colon cancer cells.

    Jingshu Wang

    Full Text Available Ursolic acid (UA, a natural pentacyclic triterpenoid carboxylic acid distributed in medical herbs, exerts antitumor effects and is emerging as a promising compound for cancer prevention and therapy, but its excise mechanisms of action in colon cancer cells remains largely unknown. Here, we identified the molecular mechanisms by which UA inhibited cell proliferation and induced apoptosis in human colon cancer SW480 and LoVo cells. Treatment with UA led to significant inhibitions in cell viability and clone formation and changes in cell morphology and spreading. UA also suppressed colon cancer cell migration by inhibiting MMP9 and upregulating CDH1 expression. Further studies showed that UA inhibited the phosphorylation of Akt and ERK proteins. Pretreatment with an Akt or ERK-specific inhibitor considerably abrogated the proliferation inhibition by UA. UA also significantly inhibited colon cancer cell COX-2 expression and PGE2 production. Pretreatment with a COX-2 inhibitor (celecoxib abrogated the UA-induced cell proliferation. Moreover, we found that UA effectively promoted NF-κB and p300 translocation from cell nuclei to cytoplasm, and attenuated the p300-mediated acetylation of NF-κB and CREB2. Pretreatment with a p300 inhibitor (roscovitine abrogated the UA-induced cell proliferation, which is reversed by p300 overexpression. Furthermore, UA treatment induced colon cancer cell apoptosis, increased the cleavage of PARP, caspase-3 and 9, and trigged the release of cytochrome c from mitochondrial inter-membrane space into cytosol. These results indicate that UA inhibits cell proliferation and induces apoptosis in colon cancer cells through simultaneous modulation of the multiple signaling pathways such as MMP9/CDH1, Akt/ERK, COX-2/PGE2, p300/NF-κB/CREB2, and cytochrome c/caspase pathways.

  17. Activation of γ-aminobutyric Acid (A) Receptor Protects Hippocampus from Intense Exercise-induced Synapses Damage and Apoptosis in Rats

    Yi Ding; Lan Xie; Cun-Qing Chang; Zhi-Min Chen; Hua Ai

    2015-01-01

    Background: Our previous study has confirmed that one bout of exhaustion (Ex) can cause hippocampus neurocyte damage, excessive apoptosis, and dysfunction. Its initial reason is intracellular calcium overload in hippocampus triggered by N-methyl-D-aspartic acid receptor (NMDAR) over-activation. NMDAR activation can be suppressed by γ-aminobutyric acid (A) receptor (GABAAR). Whether GABAAR can prevent intense exercise-induced hippocampus apoptosis, damage, or dysfunction will be studied in thi...

  18. Okadaic acid inhibits cell multiplication and induces apoptosis in a549 cells, a human lung adenocarcinoma cell line

    Wang, Renjun; Lv, Lili; Zhao, Yunfeng; Yang, Nana

    2014-01-01

    This essay aims to research the effect of okadaic acid (OA) on A549 cell multiplication, and cell apoptosis induced by OA was observed by cell morphology. MTT assay, trypan blue exclusion test (TBET), Giemsa staining method and acridine orange (AO) fluorescence staining assay were applied. The results of cell survival evaluated by TBET and colorimetric assay with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) showed: The number of A549 cells was decreased in a dose-depende...

  19. Protocatechuic Acid Prevents oxLDL-Induced Apoptosis by Activating JNK/Nrf2 Survival Signals in Macrophages.

    Varì, Rosaria; Scazzocchio, Beatrice; Santangelo, Carmela; Filesi, Carmelina; Galvano, Fabio; D'Archivio, Massimo; Masella, Roberta; Giovannini, Claudio

    2015-01-01

    Protocatechuic acid (PCA), one of the main metabolites of complex polyphenols, exerts numerous biological activities including antiapoptotic, anti-inflammatory, and antiatherosclerotic effects. Oxidised LDL have atherogenic properties by damaging arterial wall cells and inducing p53-dependent apoptosis in macrophages. This study was aimed at defining the molecular mechanism responsible for the protective effects of PCA against oxidative and proapoptotic damage exerted by oxLDL in J774 A.1 macrophages. We found that the presence of PCA in cells treated with oxLDL completely inhibited the p53-dependent apoptosis induced by oxLDL. PCA decreased oxLDL-induced ROS overproduction and in particular prevented the early increase of ROS. This decrease seemed to be the main signal responsible for maintaining the intracellular redox homeostasis hindering the activation of p53 induced by ROS, p38MAPK, and PKCδ. Consequently the overexpression of the proapoptotic p53-target genes such as p66Shc protein did not occur. Finally, we demonstrated that PCA induced the activation of JNK, which, in turn, determined the increase of nuclear Nrf2, leading to inhibition of the early ROS overproduction. We concluded that the antiapoptotic mechanism of PCA was most likely related to the activation of the JNK-mediated survival signals that strengthen the cellular antioxidant defences rather than to the PCA antioxidant power. PMID:26180584

  20. Protocatechuic Acid Prevents oxLDL-Induced Apoptosis by Activating JNK/Nrf2 Survival Signals in Macrophages

    Rosaria Varì

    2015-01-01

    Full Text Available Protocatechuic acid (PCA, one of the main metabolites of complex polyphenols, exerts numerous biological activities including antiapoptotic, anti-inflammatory, and antiatherosclerotic effects. Oxidised LDL have atherogenic properties by damaging arterial wall cells and inducing p53-dependent apoptosis in macrophages. This study was aimed at defining the molecular mechanism responsible for the protective effects of PCA against oxidative and proapoptotic damage exerted by oxLDL in J774 A.1 macrophages. We found that the presence of PCA in cells treated with oxLDL completely inhibited the p53-dependent apoptosis induced by oxLDL. PCA decreased oxLDL-induced ROS overproduction and in particular prevented the early increase of ROS. This decrease seemed to be the main signal responsible for maintaining the intracellular redox homeostasis hindering the activation of p53 induced by ROS, p38MAPK, and PKCδ. Consequently the overexpression of the proapoptotic p53-target genes such as p66Shc protein did not occur. Finally, we demonstrated that PCA induced the activation of JNK, which, in turn, determined the increase of nuclear Nrf2, leading to inhibition of the early ROS overproduction. We concluded that the antiapoptotic mechanism of PCA was most likely related to the activation of the JNK-mediated survival signals that strengthen the cellular antioxidant defences rather than to the PCA antioxidant power.

  1. Retinoic Acid Induces Apoptosis of Prostate Cancer DU145 Cells through Cdk5 Overactivation

    Mei-Chih Chen

    2012-01-01

    Full Text Available Retinoic acid (RA has been believed to be an anticancer drug for a long history. However, the molecular mechanisms of RA actions on cancer cells remain diverse. In this study, the dose-dependent inhibition of RA on DU145 cell proliferation was identified. Interestingly, RA treatment triggered p35 cleavage (p25 formation and Cdk5 overactivation, and all could be blocked by Calpain inhibitor, Calpeptin (CP. Subsequently, RA-triggered DU145 apoptosis detected by sub-G1 phase accumulation and Annexin V staining could also be blocked by CP treatment. Furthermore, RA-triggered caspase 3 activation and following Cdk5 over-activation were destroyed by treatments of both CP and Cdk5 knockdown. In conclusion, we report a new mechanism in which RA could cause apoptosis of androgen-independent prostate cancer cells through p35 cleavage and Cdk5 over-activation. This finding may contribute to constructing a clearer image of RA function and bring RA as a valuable chemoprevention agent for prostate cancer patients.

  2. Melatonin reduces bacterial translocation and apoptosis in trinitrobenzene sulphonic acid-induced colitis of rats

    2008-01-01

    AIM:To investigate the effects of exogenous melatonin on bacterial translocation and apoptosis in a rat ulcerative colitis model.METHODS:Rats were randomly assigned to three groups:group Ⅰ:control,group Ⅱ: experimental colitis,group Ⅲ:colitis plus melatonin treatment.On d 11 after colitis,plasma tumor necrosis factor-α,portal blood endotoxin levels,colon tissue myeloperoxidase and caspase-3 activity were measured.Bacterial translocation was quantified by blood,lymph node,liver and spleen culture.RESULTS:We observed a significantly reduced incidence of bacterial translocation to the liver,spleen,mesenteric lymph nodes,portal and systemic blood in animals treated with melatonin.Treatment with melatonin significantly decreased the caspase-3 activity in colonic tissues compared to that in trinitrobenzene sulphonic acid-treated rats (16.11 ± 2.46 vs 32.97 ± 3.91,P < 0.01).CONCLUSION:Melatonin has a protective effect on bacterial translocation and apoptosis.

  3. Modulation of TNF-related apoptosis inducing ligand apoptosis in colon cancer cells by omega-3 docosahexaenoic fatty acid

    Skender, B.; Hýžďalová, Martina; Vaculová, Alena; Kozubík, Alois; Hofmanová, Jiřina

    2009. s. 223. ISSN 1742-464X. [34th FEBS Congress. 04.07.2009-09.07.2009, Prague] R&D Projects: GA ČR(CZ) GA524/07/1178; GA ČR(CZ) GA301/07/1557; GA AV ČR(CZ) 1QS500040507 Institutional research plan: CEZ:AV0Z50040507; CEZ:AV0Z50040702 Keywords : DHA * TRAIL * apoptosis Subject RIV: BO - Biophysics

  4. Carnosic acid inhibits STAT3 signaling and induces apoptosis through generation of ROS in human colon cancer HCT116 cells.

    Kim, Do-Hee; Park, Ki-Woong; Chae, In Gyeong; Kundu, Juthika; Kim, Eun-Hee; Kundu, Joydeb Kumar; Chun, Kyung-Soo

    2016-06-01

    Carnosic acid (CA), the main antioxidant compound of Rosmarinus officinalis L., has been reported to possess anticancer activity. However, the molecular mechanisms underlying the anticancer effects of CA remain poorly understood. Our study revealed that CA treatment significantly reduced the viability of human colon cancer HCT116, SW480, and HT-29 cells. Treatment with CA induced apoptosis, which was associated with the induction of p53 and Bax, inhibition of Mdm2, Bcl-2, and Bcl-xl expression, activation of caspase-9, and -3, and the cleavage of PARP in HCT116 cells. CA inhibited the constitutive phosphorylation, the DNA binding and the reporter gene activity of STAT3 in HCT116 cells by blocking the phosphorylation of upstream JAK2 and Src kinases. Moreover, CA attenuated the expression of STAT3 target gene products, such as survivin, cyclin D1, D2, and D3. In STAT3-overexpressed HCT116 cells, CA inhibited cell viability and the expression of cyclin D1 and survivin. Furthermore, CA treatment induced the generation of ROS in these colon cancer cells. Pretreatment of cells with ROS scavenger N-acetyl cysteine abrogated the inhibitory effect of CA on the JAK2-STAT3/Src-STAT3 signaling and rescued cells from CA-induced apoptosis by blocking the induction of p53 and the cleavage of caspase-3 and PARP in HCT116 cells. However, L-buthionine-sulfoximine, a pharmacological inhibitor of GSH synthesis, increased CA-induced ROS production, thereby potentiating apoptotic effect of CA. In conclusion, our study provides the first report that CA induced apoptosis in HCT116 cells via generation of ROS, induction of p53, activation of caspases, and inhibition of STAT3 signaling pathway. © 2015 Wiley Periodicals, Inc. PMID:26152521

  5. Salicylic acid induces apoptosis in colon carcinoma cells grown in-vitro: Influence of oxygen and salicylic acid concentration

    In solid tumors the hypoxic environment can promote tumor progression and resistance to therapy. Recently, acetylsalicylic acid a major component of analgesic drugs and its metabolite salicylic acid (SA) have been shown to reduce the risk of colon cancer, but the mechanisms of action remain still unclear. Here we elucidate the effects of physiologically relevant concentrations of SA on colon carcinoma cells (CaCo-2) grown under normoxic and hypoxic conditions. Western blotting, caspase-3/7 apoptosis assays, MTS cell-proliferation assays, LDH cytotoxicity assays and hydrogen peroxide measurements were performed to investigate the effects of 1 and 10 μM SA on CaCo-2 cells grown under normoxic conditions and cells exposed to hypoxia. Under normoxic conditions, SA did not influence cell proliferation or LDH release of CaCo-2 cells. However, caspase-3/7 activity was significantly increased. Under hypoxia, cell proliferation was reduced and LDH release and caspase-3/7 activities were increased. None of these parameters was altered by the addition of SA under hypoxic conditions. Hypoxia increased hydrogen peroxide concentrations 300-fold and SA significantly augmented the release of hydrogen peroxide under normoxic, but not under hypoxic conditions. Phosphorylation of the pro-survival kinases akt and erk1/2 was not changed by SA under hypoxic conditions, whereas under normoxia SA reduced phosphorylation of erk1/2 after 2 hours. We conclude that in colon carcinoma cells effects of SA on apoptosis and cellular signaling are dependent on the availability of oxygen. -- Highlights: ► Effects of salicylic acid on colon carcinoma cells grown under normoxic and hypoxic conditions ► Salicylic acid increases caspase-3/7 activity and hydrogen peroxide release under normoxia ► Salicylic acid decreases pro-survival erk-1/2 phosphorylation under normoxia ► Salicylic acid does not influence any of the investigated parameters under hypoxia

  6. Salicylic acid induces apoptosis in colon carcinoma cells grown in-vitro: Influence of oxygen and salicylic acid concentration

    Zitta, Karina; Meybohm, Patrick; Bein, Berthold; Huang, Ying; Heinrich, Christin; Scholz, Jens; Steinfath, Markus; Albrecht, Martin, E-mail: Albrecht@anaesthesie.uni-kiel.de

    2012-04-15

    In solid tumors the hypoxic environment can promote tumor progression and resistance to therapy. Recently, acetylsalicylic acid a major component of analgesic drugs and its metabolite salicylic acid (SA) have been shown to reduce the risk of colon cancer, but the mechanisms of action remain still unclear. Here we elucidate the effects of physiologically relevant concentrations of SA on colon carcinoma cells (CaCo-2) grown under normoxic and hypoxic conditions. Western blotting, caspase-3/7 apoptosis assays, MTS cell-proliferation assays, LDH cytotoxicity assays and hydrogen peroxide measurements were performed to investigate the effects of 1 and 10 {mu}M SA on CaCo-2 cells grown under normoxic conditions and cells exposed to hypoxia. Under normoxic conditions, SA did not influence cell proliferation or LDH release of CaCo-2 cells. However, caspase-3/7 activity was significantly increased. Under hypoxia, cell proliferation was reduced and LDH release and caspase-3/7 activities were increased. None of these parameters was altered by the addition of SA under hypoxic conditions. Hypoxia increased hydrogen peroxide concentrations 300-fold and SA significantly augmented the release of hydrogen peroxide under normoxic, but not under hypoxic conditions. Phosphorylation of the pro-survival kinases akt and erk1/2 was not changed by SA under hypoxic conditions, whereas under normoxia SA reduced phosphorylation of erk1/2 after 2 hours. We conclude that in colon carcinoma cells effects of SA on apoptosis and cellular signaling are dependent on the availability of oxygen. -- Highlights: Black-Right-Pointing-Pointer Effects of salicylic acid on colon carcinoma cells grown under normoxic and hypoxic conditions Black-Right-Pointing-Pointer Salicylic acid increases caspase-3/7 activity and hydrogen peroxide release under normoxia Black-Right-Pointing-Pointer Salicylic acid decreases pro-survival erk-1/2 phosphorylation under normoxia Black-Right-Pointing-Pointer Salicylic acid does

  7. Carnosic acid induces apoptosis through inactivation of Src/STAT3 signaling pathway in human renal carcinoma Caki cells.

    Park, Ji Eun; Park, Byoungduck; Chae, In Gyeong; Kim, Do-Hee; Kundu, Juthika; Kundu, Joydeb Kumar; Chun, Kyung-Soo

    2016-05-01

    Carnosic acid (CA), the major bioactive compound of Rosmarinus officinalis L., has been reported to possess anti-inflammatory and anticancer activities. However, the molecular mechanisms underlying the anticancer effects of CA remain poorly understood. In the present study, we investigated that CA significantly reduced the viability of human renal carcinoma Caki cells. CA-induced apoptosis was connected with the cleavage of caspase-9, -7 and -3, and that of PARP. Moreover, CA increased the expression of pro-apoptotic protein Bax and diminished the expression of anti-apoptotic protein Bcl-2 and Bcl-xL, thereby releasing cytochrome c into the cytosol. Treatment with CA in Caki cells also induced the expression of p53 and its target gene product, p27, through down-regulation of Murine double minute-2 (Mdm2). Furthermore, CA generated reactive oxygen species (ROS), and pretreatment with ROS scavenger N-acetyl cysteine (NAC) abrogated CA-induced cleavage of PARP and expression of p53. One of the key oncogenic signals is mediated through signal transducer and activator of transcription-3 (STAT3), which promotes abnormal cell proliferation. Incubation of cells with CA markedly diminished the phosphorylation of STAT3 and its upstream, Src, and reduced the expression of STAT3 responsive gene products, such as D-series of cyclins and survivin. Taken together, the present study revealed that CA induced apoptosis in Caki cells by induction of p53 and suppression of STAT3 signaling. PMID:26936454

  8. Aristolochic acid-induced apoptosis and G2 cell cycle arrest depends on ROS generation and MAP kinases activation.

    Romanov, Victor; Whyard, Terry C; Waltzer, Wayne C; Grollman, Arthur P; Rosenquist, Thomas

    2015-01-01

    Ingestion of aristolochic acids (AAs) contained in herbal remedies results in a renal disease and, frequently, urothelial malignancy. The genotoxicity of AA in renal cells, including mutagenic DNA adducts formation, is well documented. However, the mechanisms of AA-induced tubular atrophy and renal fibrosis are largely unknown. To better elucidate some aspects of this process, we studied cell cycle distribution and cell survival of renal epithelial cells treated with AAI at low and high doses. A low dose of AA induces cell cycle arrest in G2/M phase via activation of DNA damage checkpoint pathway ATM-Chk2-p53-p21. DNA damage signaling pathway is activated more likely via increased production of reactive oxygen species (ROS) caused by AA treatment then via DNA damage induced directly by AA. Higher AA concentration induced cell death partly via apoptosis. Since mitogen-activated protein kinases play an important role in cell survival, death and cell cycle progression, we assayed their function in AA-treated renal tubular epithelial cells. ERK1/2 and p38 but not JNK were activated in cells treated with AA. In addition, pharmacological inhibition of ERK1/2 and p38 as well as suppression of ROS generation with N-acetyl-L-cysteine resulted in the partial relief of cells from G2/M checkpoint and a decline of apoptosis level. Cell cycle arrest may be a mechanism for DNA repair, cell survival and reprogramming of epithelial cells to the fibroblast type. An apoptosis of renal epithelial cells at higher AA dose might be necessary to provide space for newly reprogrammed fibrotic cells. PMID:24792323

  9. Protective role of metallothionein (Ⅰ/Ⅱ) against pathological damage and apoptosis induced by dimethylarsinic acid

    Guang Jia; Yi-Qun Gu; Kung-Tung Chen; You-Yong Lu; Lei Yan; Jian-Ling Wang; Ya-Ping Su; J. C. Gaston Wu

    2004-01-01

    AIM: To better clarify the main target organs of dimethylarsinic acid toxicity and the role of metallothionein (MTs) in modifying dimethylarsinic acid (DMAA) toxicity.METHODS: MT-Ⅰ/Ⅱ null (MT-/-) mice and the corresponding wild-type mice (MT+/+), six in each group, were exposed to DMAA (0-750 mg/kg body weight) by a single oral injection.Twenty four hours later, the lungs, livers and kidneys were collected and undergone pathological analysis, induction of apoptotic cells as determined by TUNEL and MT concentration was detected by radio-immunoassay.RESULTS: Remarkable pathological lesions were observed at the doses ranging from 350 to 750 mg/kg body weight in the lungs, livers and kidneys and MT+/+ mice exhibited a relatively slight destruction when compared with that in dose matched MT-/- mice. The number of apoptotic cells was increased in a dose dependent manner in the lungs and livers in both types of mice. DMAA produced more necrotic cells rather than apoptotic cells at the highest dose of 750 mg/kg,however, no significant increase was observed in the kidney.Hepatic MT level in MT+/+ mice was significantly increased by DMAA in a dose-dependent manner and there was nodetectable amount of hepatic MT in untreated MT-/- mice.CONCLUSION: DMAA treatment can lead to the induction of apoptosis and pathological damage in both types of mice.MT exhibits a protective effect against DMAA toxicity.

  10. Omega-3 Polyunsaturated Fatty Acids Trigger Cell Cycle Arrest and Induce Apoptosis in Human Neuroblastoma LA-N-1 Cells

    Wai Wing So

    2015-08-01

    Full Text Available Omega-3 (n-3 fatty acids are dietary long-chain fatty acids with an array of health benefits. Previous research has demonstrated the growth-inhibitory effect of n-3 fatty acids on different cancer cell lines in vitro, yet their anti-tumor effects and underlying action mechanisms on human neuroblastoma LA-N-1 cells have not yet been reported. In this study, we showed that docosahexaenoic acid (DHA and eicosapentaenoic acid (EPA exhibited time- and concentration-dependent anti-proliferative effect on the human neuroblastoma LA-N-1 cells, but had minimal cytotoxicity on the normal or non-tumorigenic cells, as measured by MTT reduction assay. Mechanistic studies indicated that DHA and EPA triggered G0/G1 cell cycle arrest in LA-N-1 cells, as detected by flow cytometry, which was accompanied by a decrease in the expression of CDK2 and cyclin E proteins. Moreover, DHA and EPA could also induce apoptosis in LA-N-1 cells as revealed by an increase in DNA fragmentation, phosphatidylserine externalization and mitochondrial membrane depolarization. Up-regulation of Bax, activated caspase-3 and caspase-9 proteins, and down-regulation of Bcl-XL protein, might account for the occurrence of apoptotic events. Collectively, our results suggest that the growth-inhibitory effect of DHA and EPA on LA-N-1 cells might be mediated, at least in part, via triggering of cell cycle arrest and apoptosis. Therefore, DHA and EPA are potential anti-cancer agents which might be used for the adjuvant therapy or combination therapy with the conventional anti-cancer drugs for the treatment of some forms of human neuroblastoma with minimal toxicity.

  11. Benzene-Poly-Carboxylic Acid Complex, a Novel Anti-Cancer Agent Induces Apoptosis in Human Breast Cancer Cells

    Fares, Fuad; Azzam, Naiel; Fares, Basem; Larsen, Stig; Lindkaer-Jensen, Steen

    2014-01-01

    Some cases of breast cancer are composed of clones of hormonal-independent growing cells, which do not respond to therapy. In the present study, the effect of Benzene-Poly-Carboxylic Acid Complex (BP-C1) on growth of human breast-cancer cells was tested. BP-C1 is a novel anti-cancer complex of benzene-poly-carboxylic acids with a very low concentration of cis-diammineplatinum (II) dichloride. Human breast cancer cells, MCF-7 and T47D, were used. Cell viability was detected by XTT assay and apoptosis was detected by Flow Cytometry and by annexin V/FITC/PI assay. Caspases were detected by western blot analysis and gene expression was measured by using the Applied Biosystems® TaqMan® Array Plates. The results showed that exposure of the cells to BP-C1 for 48 h, significantly (P<0.001) reduced cell viability, induced apoptosis and activated caspase 8 and caspace 9. Moreover, gene expression experiments indicated that BP-C1 increased the expression of pro-apoptotic genes (CASP8AP1, TNFRSF21, NFkB2, FADD, BCL10 and CASP8) and lowered the level of mRNA transcripts of inhibitory apoptotic genes (BCL2L11, BCL2L2 and XIAP. These findings may lead to the development of new therapeutic strategies for treatment of human cancer using BP-C1 analog. PMID:24523856

  12. Down-Regulation of AKT Signalling by Ursolic Acid Induces Intrinsic Apoptosis and Sensitization to Doxorubicin in Soft Tissue Sarcoma

    Villar, Victor Hugo; Vögler, Oliver; Barceló, Francisca; Martín-Broto, Javier; Martínez-Serra, Jordi; Ruiz-Gutiérrez, Valentina; Alemany, Regina

    2016-01-01

    Several important biological activities have been attributed to the pentacyclic triterpene ursolic acid (UA), being its antitumoral effect extensively studied in human adenocarcinomas. In this work, we focused on the efficacy and molecular mechanisms involved in the antitumoral effects of UA, as single agent or combined with doxorubicin (DXR), in human soft tissue sarcoma cells. UA (5–50 μM) strongly inhibited (up to 80%) the viability of STS cells at 24 h and its proliferation in soft agar, with higher concentrations increasing apoptotic death up to 30%. UA treatment (6–9 h) strongly blocked the survival AKT/GSK3β/β-catenin signalling pathway, which led to a concomitant reduction of the anti-apoptotic proteins c-Myc and p21, altogether resulting in the activation of intrinsic apoptosis. Interestingly, UA at low concentrations (10–15 μM) enhanced the antitumoral effects of DXR by up to 2-fold, while in parallel inhibiting DXR-induced AKT activation and p21 expression, two proteins implicated in antitumoral drug resistance and cell survival. In conclusion, UA is able to induce intrinsic apoptosis in human STS cells and also to sensitize these cells to DXR by blocking the AKT signalling pathway. Therefore, UA may have beneficial effects, if used as nutraceutical adjuvant during standard chemotherapy treatment of STS. PMID:27219337

  13. Down-Regulation of AKT Signalling by Ursolic Acid Induces Intrinsic Apoptosis and Sensitization to Doxorubicin in Soft Tissue Sarcoma.

    Victor Hugo Villar

    Full Text Available Several important biological activities have been attributed to the pentacyclic triterpene ursolic acid (UA, being its antitumoral effect extensively studied in human adenocarcinomas. In this work, we focused on the efficacy and molecular mechanisms involved in the antitumoral effects of UA, as single agent or combined with doxorubicin (DXR, in human soft tissue sarcoma cells. UA (5-50 μM strongly inhibited (up to 80% the viability of STS cells at 24 h and its proliferation in soft agar, with higher concentrations increasing apoptotic death up to 30%. UA treatment (6-9 h strongly blocked the survival AKT/GSK3β/β-catenin signalling pathway, which led to a concomitant reduction of the anti-apoptotic proteins c-Myc and p21, altogether resulting in the activation of intrinsic apoptosis. Interestingly, UA at low concentrations (10-15 μM enhanced the antitumoral effects of DXR by up to 2-fold, while in parallel inhibiting DXR-induced AKT activation and p21 expression, two proteins implicated in antitumoral drug resistance and cell survival. In conclusion, UA is able to induce intrinsic apoptosis in human STS cells and also to sensitize these cells to DXR by blocking the AKT signalling pathway. Therefore, UA may have beneficial effects, if used as nutraceutical adjuvant during standard chemotherapy treatment of STS.

  14. Curcumin inhibits intracellular fatty acid synthase and induces apoptosis in human breast cancer MDA-MB-231 cells.

    Fan, Huijin; Liang, Yan; Jiang, Bing; Li, Xiabing; Xun, Hang; Sun, Jia; He, Wei; Lau, Hay Tong; Ma, Xiaofeng

    2016-05-01

    High levels of fatty acid synthase (FAS) expression have been found in many tumors, including prostate, breast, and ovarian cancers, and inhibition of FAS has been reported to obstruct tumor growth in vitro and in vivo. Curcumin is one of the major active ingredients of Curcuma longa, which has been proven to inhibit the growth of cancer cells. In the present study, we investigated the potential activity of curcumin as a FAS inhibitor for chemoprevention of breast cancer. As a result, curcumin induced human breast cancer MDA-MB-231 cell apoptosis with the half-inhibitory concentration value of 3.63 ± 0.26 µg/ml, and blocked FAS activity, expression and mRNA level in a dose-dependent manner. Curcumin also regulated B-cell lymphoma 2 (Bcl-2), Bax and p-Akt protein expression in MDA-MB-231 cells. Moreover, FAS knockdown showed similar effect as curcumin. All these results suggested that curcumin may induce cell apoptosis via inhibiting FAS. PMID:26985864

  15. Carnosic acid induces apoptosis associated with mitochondrial dysfunction and Akt inactivation in HepG2 cells.

    Xiang, Qisen; Ma, Yunfang; Dong, Jilin; Shen, Ruiling

    2015-02-01

    Carnosic acid (CA), a phenolic diterpene isolated from rosemary, shows potential benefits in health promotion and disease prevention. In the present study, the cytotoxic and apoptotic-inducing effects of CA on human hepatocellular carcinoma HepG2 cells were investigated. The MTT assay results indicated that CA decreased cell viability in HepG2 cells in a dose-dependent manner. Treatment with CA caused a rapid Caspase-3 activation and subsequently proteolytic cleavage of poly (ADP-ribose) polymerase (PARP), both of which were markers of cells undergoing apoptosis. CA also dissipated mitochondrial membrane potential and decreased the ratio of Bcl-2/Bax protein, which mediated cytosolic translocation of cytochrome c from the mitochondria. Furthermore, CA reduced the phosphorylation of Akt, which was partially inhibited by insulin, an activator of phosphatidylinositol 3-kinase (PI3K)/Akt signalling pathway. In conclusion, our data suggest that the mitochondrial dysfunction and deactivation of Akt may contribute to the apoptosis-inducing effects of CA. PMID:25265205

  16. Protection of neuroblastoma Neuro2A cells from hypoxia-induced apoptosis by cyclic phosphatidic acid (cPA.

    Mari Gotoh

    Full Text Available Cyclic phosphatidic acid (cPA is a naturally occurring phospholipid mediator with a unique cyclic phosphate ring at the sn-2 and sn-3 positions of its glycerol backbone. We have previously shown that cPA significantly suppresses ischemia-induced delayed neuronal death and the accumulation of glial fibrillary acidic protein in the CA1 region of the rat hippocampus. These results indicated that the systemic administration of cPA can protect hippocampal neurons against ischemia-induced delayed neuronal cell death. In the current study, we investigated the effects of cPA on neuronal cell death caused by hypoxia in vitro and the molecular mechanisms underlying these effects. We used cobalt chloride (CoCl(2 to expose cells to hypoxic conditions in vitro. Treating mouse neuroblastoma (Neuro2A cells with CoCl(2 induced nuclear DNA condensation and phosphatidylserine exposure. However, adding cPA led to the suppression of CoCl(2-induced apoptosis in a cPA dose-dependent manner and attenuated the increase in the Bax/Bcl-2 ratio caused by CoCl(2. Quantitative PCR analysis showed that Neuro2A cells strongly express the LPA(1, LPA(2, and LPA(6, which are G-protein coupled receptors that can be activated by cPA. To date, LPA(1 and LPA(2 have been reported to exhibit antiapoptotic activity. Therefore, to assess the roles of LPA(1 and LPA(2 on cPA-induced neuroprotective functions, Ki16425, a selective LPA(1 and LPA(3 antagonist, was adopted to know the LPA(1 function and siRNA was used to knockdown the expression of LPA(2. On the basis of our results, we propose that cPA-induced protection of Neuro2A cells from CoCl(2-induced hypoxia damage is mediated via LPA(2.

  17. Ursolic acid from Trailliaedoxa gracilis induces apoptosis in medullary thyroid carcinoma cells.

    Aguiriano-Moser, Victor; Svejda, Bernhard; Li, Zeng-Xia; Sturm, Sonja; Stuppner, Hermann; Ingolic, Elisabeth; Höger, Harald; Siegl, Veronika; Meier-Allard, Nathalie; Sadjak, Anton; Pfragner, Roswitha

    2015-10-01

    Medullary thyroid carcinoma (MTC) originates from the C‑cells of the thyroid and is not sensitive to radiation or chemotherapy. Therefore, surgical removal of the tumor tissue in its entirety is the only curative treatment for MTC. The present study aimed to examine the potential mechanisms of action of extracts of Trailliaedoxa gracilis (TG; WW Smith & Forrest), a plant from the province of Sichuan, China, and of ursolic acid (UA), a pentacyclic triterpen present in TG, on the MTC‑SK MTC cell line. A total of 13 TG fractions and UA were examined in vitro for their effects on cell morphology, cell number, proliferation and rates of apoptosis. Reverse transcription‑quantitative polymerase chain reaction of nuclear factor‑κB essential modifier (NEMO) was performed to delineate the role of the apoptotic pathway following treatment with UA. TG and UA were examined in vivo in xenotransplanted MTC‑bearing severe combined immunodeficient mice. The TG fractions exhibited antiproliferative effects, with inhibition of mitochondrial activity in the tumor cells at concentrations, which caused no impairment of the normal control cells. The apoptotic rates of the MTC‑SK cells treated with the TG fractions and UA were determined, in which no marked tumor inhibition was observed in the treated MTC‑mice, and no change in the expression of NEMO was detected in the treated MTC‑SK cells. The observation of early‑onset activation of caspase 8 suggested that the responsible factor was linked to NEMO, an anti‑apoptotic protein. However, no differences in the mRNA transcription levels of NEMO were detected in MTC‑SK cells treated with UA, suggesting that this protein was not associated with the signal transducer and activator of transcription 3 pathway. PMID:26151624

  18. Corosolic acid analogue, a natural triterpenoid saponin, induces apoptosis on human hepatocarcinoma cells through mitochondrial pathway in vitro.

    Qu, Liping; Zhang, Huiqing; Yang, Yanlong; Yang, Geliang; Xin, Hailiang; Ling, Changquan

    2016-08-01

    Context 2a,-3a,-24-Trihydroxyurs-12-en-28-oic acid (TEO, a corosolic acid analogue) is a triterpenoid saponin isolated from Actinidia valvata Dunn (Actinidiaceae), a well-known traditional Chinese medicine. Objective This study investigated the anti-proliferation and inducing apoptosis effects of TEO in three human hepatocellular carcinoma (HCC) cell lines. Materials and methods Cytotoxic activity of TEO was determined by the MTT assay at various concentrations from 2.5 to 40 μg/mL in BEL-7402, BEL-7404 and SMMC-7721 cell lines. Cell morphology was assessed by acridine orange/ethidium bromide and 4'-6-diamidino-2-phenylindole dihydrochloride staining and fluorescence microscopy. Cell-cycle distribution and DNA damage were determined by flow cytometry and comet assay. Mitochondrial dysfunction was assessed by JC-1 staining and transmission electron microscopy. Apoptosis changes were explored by Western blot, TNF-α and caspase-3, -8, -9 assays. Results TEO exhibited inhibition effects on BEL-7402, BEL-7404 and SMMC-7721 cells treated for 24 h, the IC50 values were 34.6, 30.8 and 30.5 μg/mL, respectively. TEO (40 μg/mL)-treated three cell lines increased by more than 21% in the G1 phase and presented the morphological change and DNA damage. TEO also declined the mitochondrial membrane potential and altered mitochondrial ultra-structure. Furthermore, caspase-3, caspase-8, caspase-9 and TNF-α were also activated. Mechanism investigation showed that TEO could decrease anti-apoptotic Bcl-2 protein expression, increase proapoptotic Bax and Bid proteins expressions and increase Bax/Bcl-2 ratio. Conclusion Our results demonstrate for the first time that TEO inhibited growth of HCC cell lines and induced G1 phase arrest. Moreover, proapoptotic effects of TEO were mediated through the activation of TNF-α, caspases and mitochondrial pathway. PMID:26810384

  19. Nucleotide excision repair deficiency increases levels of acrolein-derived cyclic DNA adduct and sensitizes cells to apoptosis induced by docosahexaenoic acid and acrolein.

    Pan, Jishen; Sinclair, Elizabeth; Xuan, Zhuoli; Dyba, Marcin; Fu, Ying; Sen, Supti; Berry, Deborah; Creswell, Karen; Hu, Jiaxi; Roy, Rabindra; Chung, Fung-Lung

    2016-07-01

    The acrolein derived cyclic 1,N(2)-propanodeoxyguanosine adduct (Acr-dG), formed primarily from ω-3 polyunsaturated fatty acids such as docosahexaenoic acid (DHA) under oxidative conditions, while proven to be mutagenic, is potentially involved in DHA-induced apoptosis. The latter may contribute to the chemopreventive effects of DHA. Previous studies have shown that the levels of Acr-dG are correlated with apoptosis induction in HT29 cells treated with DHA. Because Acr-dG is shown to be repaired by the nucleotide excision repair (NER) pathway, to further investigate the role of Acr-dG in apoptosis, in this study, NER-deficient XPA and its isogenic NER-proficient XAN1 cells were treated with DHA. The Acr-dG levels and apoptosis were sharply increased in XPA cells, but not in XAN1 cells when treated with 125μM of DHA. Because DHA can induce formation of various DNA damage, to specifically investigate the role of Acr-dG in apoptosis induction, we treated XPA knockdown HCT116+ch3 cells with acrolein. The levels of both Acr-dG and apoptosis induction increased significantly in the XPA knockdown cells. These results clearly demonstrate that NER deficiency induces higher levels of Acr-dG in cells treated with DHA or acrolein and sensitizes cells to undergo apoptosis in a correlative manner. Collectively, these results support that Acr-dG, a ubiquitously formed mutagenic oxidative DNA adduct, plays a role in DHA-induced apoptosis and suggest that it could serve as a biomarker for the cancer preventive effects of DHA. PMID:27036235

  20. Effect of apoptosis on gastric adenocarcinoma cell line SGC—7901 induced by cis—9,trans—11—conjugated linoleic acid

    Jia-RenLiu; Bing-QingChen; Yan-MeiYang; Xuan-LingWang; Ying-BenXue

    2002-01-01

    AIM:To determine the effect of apoptosis on gastric cancer cells(SGC-7901)induced by cis-9,trans-11-conjugated linoleic acid(c9,t11-CLA)and its possible mechanism in the inhibition of cancer cells growth.

  1. Mitochondrial genome depletion in human liver cells abolishes bile acid-induced apoptosis: role of the Akt/mTOR survival pathway and Bcl-2 family proteins.

    Marin, Jose J G; Hernandez, Alicia; Revuelta, Isabel E; Gonzalez-Sanchez, Ester; Gonzalez-Buitrago, Jose M; Perez, Maria J

    2013-08-01

    Acute accumulation of bile acids in hepatocytes may cause cell death. However, during long-term exposure due to prolonged cholestasis, hepatocytes may develop a certain degree of chemoresistance to these compounds. Because mitochondrial adaptation to persistent oxidative stress may be involved in this process, here we have investigated the effects of complete mitochondrial genome depletion on the response to bile acid-induced hepatocellular injury. A subline (Rho) of human hepatoma SK-Hep-1 cells totally depleted of mitochondrial DNA (mtDNA) was obtained, and bile acid-induced concentration-dependent activation of apoptosis/necrosis and survival signaling pathways was studied. In the absence of changes in intracellular ATP content, Rho cells were highly resistant to bile acid-induced apoptosis and partially resistant to bile acid-induced necrosis. In Rho cells, both basal and bile acid-induced generation of reactive oxygen species (ROS), such as hydrogen peroxide and superoxide anion, was decreased. Bile acid-induced proapoptotic signals were also decreased, as evidenced by a reduction in the expression ratios Bax-α/Bcl-2, Bcl-xS/Bcl-2, and Bcl-xS/Bcl-xL. This was mainly due to a downregulation of Bax-α and Bcl-xS. Moreover, in these cells the Akt/mTOR pathway was constitutively activated in a ROS-independent manner and remained similarly activated in the presence of bile acid treatment. In contrast, ERK1/2 activation was constitutively reduced and was not activated by incubation with bile acids. In conclusion, these results suggest that impaired mitochondrial function associated with mtDNA alterations, which may occur in liver cells during prolonged cholestasis, may activate mechanisms of cell survival accounting for an enhanced resistance of hepatocytes to bile acid-induced apoptosis. PMID:23597504

  2. Apoptosis versus differentiation induced by interaction of butyrate and unsaturated fatty acids in normal and transformed colonic epithelial cells

    Hofmanová, Jiřina; Vaculová, Alena; Hýžďalová, Martina; Koubková, Zuzana; Netíková, Jaromíra; Kozubík, Alois

    Chia, Sardinia, 2006. P-103-P-103. [14th Euroconference on Apoptosis "Death or Survival? Fate in Sardinia". 29.09.2006-04.10.2006, Chia, Sardinia] R&D Projects: GA ČR(CZ) GA524/04/0895; GA AV ČR(CZ) 1QS500040507 Institutional research plan: CEZ:AV0Z50040507 Keywords : colon cancer * fatty acide * apoptosis Subject RIV: BO - Biophysics

  3. Melatonin reduces bacterial translocation and apoptosis in trinitrobenzene sulphonic acid-induced colitis of rats

    Alper Akcan, Can Kucuk, Erdogan Sozuer, Duygu Esel, Hizir Akyildiz, Hulya Akgun, Sabahattin Muhtaroglu, Yucel Aritas

    2008-01-01

    AIM: To investigate the effects of exogenous melatonin on bacterial translocation and apoptosis in a rat ulcerative colitis model.METHODS: Rats were randomly assigned to three groups: groupI: control, group II: experimental colitis, group III: colitis plus melatonin treatment. On d 11 after colitis, plasma tumor necrosis factor-α, portal blood endotoxin levels, colon tissue myeloperoxidase and caspase-3 activity were measured. Bacterial translocation was quantified by blood, lymph node, liver...

  4. c-Abl is an upstream regulator of acid sphingomyelinase in apoptosis induced by inhibition of integrins αvβ3 and αvβ5.

    Xiuhai Ren

    Full Text Available Inhibition of integrins αvβ3/αvβ5 by the cyclic function-blocking peptide, RGDfV (Arg-Gly-Asp-Phe-Val can induce apoptosis in both normal cells and tumor cells. We show that RGDfV induced apoptosis in ECV-304 carcinoma cells, increased activity and mRNA expression of acid sphingomyelinase (ASM, and increased ceramides C(16, C(18:0, C(24:0 and C(24:1 while decreasing the corresponding sphingomyelins. siRNA to ASM decreased RGDfV-induced apoptosis as measured by TUNEL, PARP cleavage, mitochondrial depolarization, and caspase-3 and caspase-8 activities, as well as by annexinV in a 3D collagen model. These findings indicate a causal role for ASM in RGDfV-induced apoptosis in ECV-304. We have shown that c-Abl, a non-receptor tyrosine kinase, also mediates RGDfV-induced apoptosis. However, c-Abl, has not been previously linked to ASM in any system. Here we show that STI-571 (imatinib, inhibitor of c-Abl inhibited RGDfV-induced ASM activity. Furthermore, STI-571 and c-Abl-siRNA both inhibited RGDfV-induced increase in ASM mRNA, but ASM-siRNA did not affect c-Abl phosphorylation or expression, supporting that c-Abl regulates the RGDfV-induced increase in ASM expression. These studies implicate ASM as a mediator of apoptosis induced by inhibition of integrins αvβ3/αvβ5, and for the first time place c-Abl as an upstream regulator of ASM expression and activity.

  5. Isoliquiritigenin induces growth inhibition and apoptosis through downregulating arachidonic acid metabolic network and the deactivation of PI3K/Akt in human breast cancer

    Li, Ying; Zhao, Haixia [Department of Pharmacology, School of Medicine, Wuhan University, Wuhan 430071 (China); Wang, Yuzhong [Key Laboratory for Oral Biomedical Engineering of Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan 430079 (China); Zheng, Hao; Yu, Wei; Chai, Hongyan [Department of Pharmacology, School of Medicine, Wuhan University, Wuhan 430071 (China); Zhang, Jing [Animal Experimental Center of Wuhan University, Wuhan 430071 (China); Falck, John R. [Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX 75390,USA (United States); Guo, Austin M. [Department of Pharmacology, School of Medicine, Wuhan University, Wuhan 430071 (China); Department of Pharmacology, New York Medical College, Valhalla, NY 10595 (United States); Yue, Jiang; Peng, Renxiu [Department of Pharmacology, School of Medicine, Wuhan University, Wuhan 430071 (China); Yang, Jing, E-mail: yangjingliu2013@163.com [Department of Pharmacology, School of Medicine, Wuhan University, Wuhan 430071 (China); Research Center of Food and Drug Evaluation, Wuhan University, Wuhan 430071 (China)

    2013-10-01

    Arachidonic acid (AA)-derived eicosanoids and its downstream pathways have been demonstrated to play crucial roles in growth control of breast cancer. Here, we demonstrate that isoliquiritigenin, a flavonoid phytoestrogen from licorice, induces growth inhibition and apoptosis through downregulating multiple key enzymes in AA metabolic network and the deactivation of PI3K/Akt in human breast cancer. Isoliquiritigenin diminished cell viability, 5-bromo-2′-deoxyuridine (BrdU) incorporation, and clonogenic ability in both MCF-7 and MDA-MB-231cells, and induced apoptosis as evidenced by an analysis of cytoplasmic histone-associated DNA fragmentation, flow cytometry and hoechst staining. Furthermore, isoliquiritigenin inhibited mRNA expression of multiple forms of AA-metabolizing enzymes, including phospholipase A2 (PLA2), cyclooxygenases (COX)-2 and cytochrome P450 (CYP) 4A, and decreased secretion of their products, including prostaglandin E{sub 2} (PGE{sub 2}) and 20-hydroxyeicosatetraenoic acid (20-HETE), without affecting COX-1, 5-lipoxygenase (5-LOX), 5-lipoxygenase activating protein (FLAP), and leukotriene B{sub 4} (LTB{sub 4}). In addition, it downregulated the levels of phospho-PI3K, phospho-PDK (Ser{sup 241}), phospho-Akt (Thr{sup 308}), phospho-Bad (Ser{sup 136}), and Bcl-x{sub L} expression, thereby activating caspase cascades and eventually cleaving poly(ADP-ribose) polymerase (PARP). Conversely, the addition of exogenous eicosanoids, including PGE{sub 2}, LTB{sub 4} and a 20-HETE analog (WIT003), and caspase inhibitors, or overexpression of constitutively active Akt reversed isoliquiritigenin-induced apoptosis. Notably, isoliquiritigenin induced growth inhibition and apoptosis of MDA-MB-231 human breast cancer xenografts in nude mice, together with decreased intratumoral levels of eicosanoids and phospho-Akt (Thr{sup 308}). Collectively, these data suggest that isoliquiritigenin induces growth inhibition and apoptosis through downregulating AA metabolic

  6. Isoliquiritigenin induces growth inhibition and apoptosis through downregulating arachidonic acid metabolic network and the deactivation of PI3K/Akt in human breast cancer

    Arachidonic acid (AA)-derived eicosanoids and its downstream pathways have been demonstrated to play crucial roles in growth control of breast cancer. Here, we demonstrate that isoliquiritigenin, a flavonoid phytoestrogen from licorice, induces growth inhibition and apoptosis through downregulating multiple key enzymes in AA metabolic network and the deactivation of PI3K/Akt in human breast cancer. Isoliquiritigenin diminished cell viability, 5-bromo-2′-deoxyuridine (BrdU) incorporation, and clonogenic ability in both MCF-7 and MDA-MB-231cells, and induced apoptosis as evidenced by an analysis of cytoplasmic histone-associated DNA fragmentation, flow cytometry and hoechst staining. Furthermore, isoliquiritigenin inhibited mRNA expression of multiple forms of AA-metabolizing enzymes, including phospholipase A2 (PLA2), cyclooxygenases (COX)-2 and cytochrome P450 (CYP) 4A, and decreased secretion of their products, including prostaglandin E2 (PGE2) and 20-hydroxyeicosatetraenoic acid (20-HETE), without affecting COX-1, 5-lipoxygenase (5-LOX), 5-lipoxygenase activating protein (FLAP), and leukotriene B4 (LTB4). In addition, it downregulated the levels of phospho-PI3K, phospho-PDK (Ser241), phospho-Akt (Thr308), phospho-Bad (Ser136), and Bcl-xL expression, thereby activating caspase cascades and eventually cleaving poly(ADP-ribose) polymerase (PARP). Conversely, the addition of exogenous eicosanoids, including PGE2, LTB4 and a 20-HETE analog (WIT003), and caspase inhibitors, or overexpression of constitutively active Akt reversed isoliquiritigenin-induced apoptosis. Notably, isoliquiritigenin induced growth inhibition and apoptosis of MDA-MB-231 human breast cancer xenografts in nude mice, together with decreased intratumoral levels of eicosanoids and phospho-Akt (Thr308). Collectively, these data suggest that isoliquiritigenin induces growth inhibition and apoptosis through downregulating AA metabolic network and the deactivation of PI3K/Akt in human breast cancer

  7. Phytic Acid Protects against 6-Hydroxydopamine-Induced Dopaminergic Neuron Apoptosis in Normal and Iron Excess Conditions in a Cell Culture Model

    Qi Xu; Kanthasamy, Anumantha G.; Reddy, Manju B.

    2011-01-01

    Iron may play an important role in Parkinson's disease (PD) since it can induce oxidative stress-dependent neurodegeneration. The objective of this study was to determine whether the iron chelator, phytic acid (IP6) can protect against 6-hydroxydopamine- (6-OHDA-) induced apoptosis in immortalized rat mesencephalic dopaminergic cells under normal and iron-excess conditions. Caspase-3 activity was increased about 6-fold after 6-OHDA treatment (compared to control; < . 0 0 1 ) and 30 μmol/L I...

  8. Lipid changes in normal and cancer colon cells during differentiation and apoptosis induced by fatty acids

    Hofmanová, Jiřina; Vaculová, Alena; Hýžďalová, Martina; Koubková, Zuzana; Netíková, Jaromíra; Kozubík, Alois

    2007-01-01

    Roč. 20, č. 1 (2007), S43. ISSN 1107-3756. [12th World Congress on Advances in Oncology and 10th International Symposium on Molecular Medicine. 11.10.2007-13.10.2007, Hersonissos, Crete] R&D Projects: GA ČR(CZ) GA524/07/1178; GA AV ČR(CZ) 1QS500040507 Institutional research plan: CEZ:AV0Z50040507; CEZ:AV0Z50040702 Keywords : colon cancer * lipids * apoptosis Subject RIV: BO - Biophysics

  9. Methylseleninic acid potentiates multiple types of cancer cells to ABT-737-induced apoptosis by targeting Mcl-1 and Bad

    Yin, Shutao; Dong, Yinhui; Li, Jinghua;

    2012-01-01

    overcome such resistance to restore the sensitivity. In the present study, a second-generation selenium compound methylseleninic acid (MSeA) synergistically sensitized MDA-MB-231 human breast cancer cells, HT-29 human colon cancer cells and DU145 human prostate cancer cells to apoptosis induction by ABT...

  10. Inhibitor of fatty acid synthase induced apoptosis in human colonic cancer cells

    Pei Lin Huang; Zhen Sheng Dai; Yue Lin Jin; Shi Neng Zhu; Shi Lun Lu

    2000-01-01

    @@INTRODUCTION The treatment of human epithelial malignancies is limited by drug resistance and toxic and side effects,which results in the failure in the treatment of majority of advanced cancer victims. To seek for a new, and specific antineoplastic therapy will provide hope for tumor treatment. Although disordered intermediary metabolism in cancer cells has been known for many years, much of the work focused on abnormal glucose catabolism. At the same time, little attention has been paid to fatty acid synthasis in tumor tissues, dispite of the significance of fatty acid synthase (FAS) in some clinical human ovarian[1], breast[2], colorectal[3],and prostatic cancers[4,5]. Tumor cells which express high levels of fatty acid synthesizing enzymes use endogeneously synthesized fatty acids for membrance biosynthesis and appear to export large amounts of lipid. In contrast, normal cells preferentially utilize diary lipid.

  11. Eicosapentaenoic acid (EPA) induced apoptosis in HepG2 cells through ROS–Ca2+–JNK mitochondrial pathways

    Highlights: • EPA evoked ROS formation, [Ca2+]c accumulation, the opening of MPTP and the phosphorylation of JNK. • EPA-induced [Ca2+]c elevation was depended on production of ROS. • EPA-induced ROS generation, [Ca2+]c increase, and JNK activated caused MPTP opening. • The apoptosis induced by EPA was related to release of cytochrome C through the MPTP. • EPA induced HepG2 cells apoptosis through ROS–Ca2+–JNK mitochondrial pathways. - Abstract: Eicosapentaenoic acid (EPA), a well-known dietary n−3 PUFAS, has been considered to inhibit proliferation of tumor cells. However, the molecular mechanism related to EPA-induced liver cancer cells apoptosis has not been reported. In this study, we investigated the effect of EPA on HepG2 cells proliferation and apoptosis mechanism through mitochondrial pathways. EPA inhibited proliferation of HepG2 cells in a dose-dependent manner and had no significant effect on the cell viability of humor normal liver L-02 cells. It was found that EPA initially evoked ROS formation, leading to [Ca2+]c accumulation and the mitochondrial permeability transition pore (MPTP) opening; EPA-induced HepG2 cells apoptosis was inhibited by N-acetylcysteine (NAC, an inhibitor of ROS), 1,2-bis (2-aminophenoxy) ethane-N,N,N′,N′-tetraacetic acid (BAPTA-AM, a chelator of calcium) and CsA (inhibitor of MPTP). The relationship between ROS production, the increase of cytoplasmic Ca and MPTP opening was detected. It seems that ROS may act as an upstream regulator of EPA-induced [Ca2+]c generation, moreover, generation of ROS, overload of mitochondrial [Ca2+]c, and JNK activated cause the opening of MPTP. Western blotting results showed that EPA elevated the phosphorylation status of JNK, processes associated with the ROS generation. Simultaneously, the apoptosis induced by EPA was related to release of cytochrome C from mitochondria to cytoplasm through the MPTP and activation of caspase-9 and caspase-3. These results suggest that EPA

  12. Eicosapentaenoic acid (EPA) induced apoptosis in HepG2 cells through ROS–Ca{sup 2+}–JNK mitochondrial pathways

    Zhang, Yuanyuan; Han, Lirong [Key Laboratory of Food Nutrition and Safety, Ministry of Education, College of Food Engineering and Biotechnology, Tianjin University of Science and Technology, No. 29, 13th Avenue, Tianjin Economy Technological Development Area, Tianjin 300457 (China); Qi, Wentao [Academy of State Administration of Grain, No.11 Baiwanzhuang Avenue, Xicheng District, Beijing, 100037 (China); Cheng, Dai; Ma, Xiaolei; Hou, Lihua [Key Laboratory of Food Nutrition and Safety, Ministry of Education, College of Food Engineering and Biotechnology, Tianjin University of Science and Technology, No. 29, 13th Avenue, Tianjin Economy Technological Development Area, Tianjin 300457 (China); Cao, Xiaohong, E-mail: caoxh@tust.edu.cn [Key Laboratory of Food Nutrition and Safety, Ministry of Education, College of Food Engineering and Biotechnology, Tianjin University of Science and Technology, No. 29, 13th Avenue, Tianjin Economy Technological Development Area, Tianjin 300457 (China); Wang, Chunling, E-mail: wangchunling@tust.edu.cn [Key Laboratory of Food Nutrition and Safety, Ministry of Education, College of Food Engineering and Biotechnology, Tianjin University of Science and Technology, No. 29, 13th Avenue, Tianjin Economy Technological Development Area, Tianjin 300457 (China)

    2015-01-24

    Highlights: • EPA evoked ROS formation, [Ca{sup 2+}]{sub c} accumulation, the opening of MPTP and the phosphorylation of JNK. • EPA-induced [Ca{sup 2+}]{sub c} elevation was depended on production of ROS. • EPA-induced ROS generation, [Ca{sup 2+}]{sub c} increase, and JNK activated caused MPTP opening. • The apoptosis induced by EPA was related to release of cytochrome C through the MPTP. • EPA induced HepG2 cells apoptosis through ROS–Ca{sup 2+}–JNK mitochondrial pathways. - Abstract: Eicosapentaenoic acid (EPA), a well-known dietary n−3 PUFAS, has been considered to inhibit proliferation of tumor cells. However, the molecular mechanism related to EPA-induced liver cancer cells apoptosis has not been reported. In this study, we investigated the effect of EPA on HepG2 cells proliferation and apoptosis mechanism through mitochondrial pathways. EPA inhibited proliferation of HepG2 cells in a dose-dependent manner and had no significant effect on the cell viability of humor normal liver L-02 cells. It was found that EPA initially evoked ROS formation, leading to [Ca{sup 2+}]{sub c} accumulation and the mitochondrial permeability transition pore (MPTP) opening; EPA-induced HepG2 cells apoptosis was inhibited by N-acetylcysteine (NAC, an inhibitor of ROS), 1,2-bis (2-aminophenoxy) ethane-N,N,N′,N′-tetraacetic acid (BAPTA-AM, a chelator of calcium) and CsA (inhibitor of MPTP). The relationship between ROS production, the increase of cytoplasmic Ca and MPTP opening was detected. It seems that ROS may act as an upstream regulator of EPA-induced [Ca{sup 2+}]{sub c} generation, moreover, generation of ROS, overload of mitochondrial [Ca{sup 2+}]{sub c}, and JNK activated cause the opening of MPTP. Western blotting results showed that EPA elevated the phosphorylation status of JNK, processes associated with the ROS generation. Simultaneously, the apoptosis induced by EPA was related to release of cytochrome C from mitochondria to cytoplasm through the MPTP

  13. Ellagic acid protects endothelial cells from oxidized low-density lipoprotein-induced apoptosis by modulating the PI3K/Akt/eNOS pathway

    Endothelial apoptosis is a driving force in atherosclerosis development. Oxidized low-density lipoprotein (oxLDL) promotes inflammatory and thrombotic processes and is highly atherogenic, as it stimulates macrophage cholesterol accumulation and foam cell formation. Previous studies have shown that the phosphatidylinositol 3-kinase/Akt/endothelial nitric oxide synthase/nitric oxide (PI3K/Akt/eNOS/NO) pathway is involved in oxLDL-induced endothelial apoptosis. Ellagic acid, a natural polyphenol found in berries and nuts, has in recent years been the subject of intense research within the fields of cancer and inflammation. However, its protective effects against oxLDL-induced injury in vascular endothelial cells have not been clarified. In the present study, we investigated the anti-apoptotic effect of ellagic acid in human umbilical vein endothelial cells (HUVECs) exposed to oxLDL and explored the possible mechanisms. Our results showed that pretreatment with ellagic acid (5-20 μM) significantly attenuated oxLDL-induced cytotoxicity, apoptotic features, and generation of reactive oxygen species (ROS). In addition, the anti-apoptotic effect of ellagic acid was partially inhibited by a PI3K inhibitor (wortmannin) and a specific eNOS inhibitor (cavtratin) but not by an ERK inhibitor (PD98059). In exploring the underlying mechanisms of ellagic acid action, we found that oxLDL decreased Akt and eNOS phosphorylation, which in turn activated NF-κB and downstream pro-apoptotic signaling events including calcium accumulation, destabilization of mitochondrial permeability, and disruption of the balance between pro- and anti-apoptotic Bcl-2 proteins. Those alterations induced by oxLDL, however, were attenuated by pretreatment with ellagic acid. The inhibition of oxLDL-induced endothelial apoptosis by ellagic acid is due at least in part to its anti-oxidant activity and its ability to modulate the PI3K/Akt/eNOS signaling pathway.

  14. l-Amino acid oxidase isolated from Calloselasma rhodostoma snake venom induces cytotoxicity and apoptosis in JAK2V617F-positive cell lines

    Cristiane Tavares

    2016-06-01

    Full Text Available ABSTRACT BACKGROUND: Myeloproliferative neoplasms are Philadelphia chromosome-negative diseases characterized by hyperproliferation of mature myeloid cells, associated or not with the Janus kinase 2 tyrosine kinase mutation, JAK2V617F. As there is no curative therapy, researchers have been investigating new drugs to treat myeloproliferative neoplasms, including l-amino acid oxidase from Calloselasma rhodostoma snake venom (CR-LAAO, which is a toxin capable of eliciting apoptosis in several tumor cell lines. OBJECTIVE: To evaluate the effects of l-amino acid oxidase from C. rhodostoma snake venom in the apoptotic machinery of JAK2-mutated cell lines. METHODS: The HEL 92.1.7 and SET-2 cell lines were cultured with l-amino acid oxidase and catalase for 12 h at 37 °C in 5% carbon dioxide. The cell viability was assessed by the multi-table tournament method, the level of apoptosis was measured by flow cytometry, and the expression of cysteine-dependent aspartate-specific proteases and cleaved Poly(ADP-ribose polymerase were analyzed by Western blotting. RESULTS: l-Amino acid oxidase from C. rhodostoma snake venom was cytotoxic to HEL 92.1.7 and SET-2 cells (50% inhibitory concentration = 0.15 µg/mL and 1.5 µg/mL, respectively and induced apoptosis in a concentration-dependent manner. Cell treatment with catalase mitigated the l-amino acid oxidase toxicity, indicating that hydrogen peroxide is a key component of its cytotoxic effect.The activated caspases 3 and 8 expression and cleaved PARP in HEL 92.1.7 and SET-2 cells confirmed the apoptosis activation by CR-LAAO. CONCLUSIONS: l-Amino acid oxidase from C. rhodostoma snake venom is a potential antineoplastic agent against HEL 92.1.7 and SET-2 JAK2V617F-positive cells as it activates the extrinsic apoptosis pathway.

  15. An antibody to de-N-acetyl sialic acid containing-polysialic acid identifies an intracellular antigen and induces apoptosis in human cancer cell lines.

    Lindsay M Steirer

    Full Text Available Polysialic acid (PSA, an α2,8-linked homopolymer of N-acetylneuraminic acid (Neu5Ac, is developmentally regulated and its expression is thought to be restricted to a few tissues in adults. Recently, we showed that two human pathogens expressed a derivative of PSA containing de-N-acetyl sialic acid residues (NeuPSA. Here we show that an epitope identified by the anti-NeuPSA monoclonal antibody, SEAM 3 (SEAM 3-reactive antigen or S3RA, is expressed in human melanomas, and also intracellularly in a human melanoma cell line (SK-MEL-28, a human T cell leukemia cell line (Jurkat, and two neuroblastoma cell lines (CHP-134 and SH-SY5Y. SEAM 3 binding induced apoptosis in the four cell lines tested. The unusual intracellular distribution of S3RA was similar to that described for the PSA polysialyltransferases, STX and PST, which are also expressed in the four cell lines used here. Interestingly, suppression of PST mRNA expression by transfection of SK-MEL-28 cells with PST-specific short interfering RNA (siRNA resulted in decreased SEAM 3 binding. The results suggest further studies of the utility of antibodies such as SEAM 3 as therapeutic agents for certain malignancies.

  16. Metal-induced apoptosis: mechanisms

    The past decade has seen an intense focus on mechanisms of apoptosis. Many important observations on the various signaling pathways mediating apoptotic cell death have been made and our understanding of the importance of apoptosis in both normal growth and development and pathophysiology has greatly increased. In addition, mechanisms of metal-induced toxicity continue to be of interest given the ubiquitous nature of these contaminants. The purpose of this review is to summarize our current understanding of the apoptotic pathways that are initiated by metals, mainly established (arsenic, cadmium, chromium, nickel, beryllium) and possible (lead, antimony, cobalt) human carcinogens. Increased understanding of metal-induced apoptosis is critical to illuminate mechanisms of metal-induced carcinogenesis, as well as the potential of metal species (arsenic) as chemotherapeutic agents

  17. Gambogic acid induces mitochondria-dependent apoptosis by modulation of Bcl-2 and Bax in mantle cell lymphoma JeKo-1 cells

    Jingyan Xu; Min Zhou; Jian Ouyang; Jing Wang; Qiguo Zhang; Yong Xu; Yueyi Xu

    2013-01-01

    Objective:To study the mechanisms in gambogic acid (GA)-induced JeKo-1 human Mantle Cell Lymphoma cell apoptosis in vitro.Methods:The proliferation of GA-treated JeKo-1 cells was measured by CCK-8 assay and Ki-67 immunocytochemical detection.Apoptosis,cell cycle and mitochondrial membrane potential were measured by flow cytometric analysis.Caspase-3,-8 and-9 were detected by colorimetric assay.Bcl-2 and Bax were analyzed by Western blotting.Results:GA inhibited cell growth in a time-and dose-dependent manner.GA induces apoptosis in JeKo-1 cells but not in normal bone marrow cells,which was involved in reducing the membrane potential of mitochondria,activating caspases-3,-8 and-9 and decreasing the ratio of Bcl-2 and Bax without cell cycle arresting.Conclusions:GA induced apoptosis in human MCL JeKo-1 cells by regulating Bcl-2/Bax and activating caspase-3,-8 and-9 via mitochondrial pathway without affecting cell cycle.

  18. Poly-γ-Glutamic Acid Induces Apoptosis via Reduction of COX-2 Expression in TPA-Induced HT-29 Human Colorectal Cancer Cells

    Eun Ju Shin

    2015-04-01

    Full Text Available Poly-γ-glutamic acid (PGA is one of the bioactive compounds found in cheonggukjang, a fast-fermented soybean paste widely utilized in Korean cooking. PGA is reported to have a number of beneficial health effects, and interestingly, it has been identified as a possible anti-cancer compound through its ability to promote apoptosis in cancer cells, although the precise molecular mechanisms remain unclear. Our findings demonstrate that PGA inhibits the pro-proliferative functions of the phorbol ester 12-O-tetradecanoylphorbol-13-acetate (TPA, a known chemical carcinogen in HT-29 human colorectal cancer cells. This inhibition was accompanied by hallmark apoptotic phenotypes, including DNA fragmentation and the cleavage of poly (ADP-ribose polymerase (PARP and caspase 3. In addition, PGA treatment reduced the expression of genes known to be overexpressed in colorectal cancer cells, including cyclooxygenase 2 (COX-2 and inducible nitric oxide synthase (iNOS. Lastly, PGA promoted activation of 5' adenosine monophosphate-activated protein (AMPK in HT-29 cells. Taken together, our results suggest that PGA treatment enhances apoptosis in colorectal cancer cells, in part by modulating the activity of the COX-2 and AMPK signaling pathways. These anti-cancer functions of PGA make it a promising compound for future study.

  19. Resistance to ursolic acid-induced apoptosis through involvement of melanogenesis and COX-2/PGE2 pathways in human M4Beu melanoma cancer cells.

    Hassan, Lama; Pinon, Aline; Limami, Youness; Seeman, Josiane; Fidanzi-Dugas, Chloe; Martin, Frederique; Badran, Bassam; Simon, Alain; Liagre, Bertrand

    2016-07-01

    Melanoma is one of the most aggressive forms of cancer with a continuously growing incidence worldwide and is usually resistant to chemotherapy agents, which is due in part to a strong resistance to apoptosis. Previously, we had showed that B16-F0 murine melanoma cells undergoing apoptosis are able to delay their own death induced by ursolic acid (UA), a natural pentacyclic triterpenoid compound. We had demonstrated that tyrosinase and TRP-1 up-regulation in apoptotic cells and the subsequent production of melanin were implicated in an apoptosis resistance mechanism. Several resistance mechanisms to apoptosis have been characterized in melanoma such as hyperactivation of DNA repair mechanisms, drug efflux systems, and reinforcement of survival signals (PI3K/Akt, NF-κB and Raf/MAPK pathways). Otherwise, other mechanisms of apoptosis resistance involving different proteins, such as cyclooxygenase-2 (COX-2), have been described in many cancer types. By using a strategy of specific inhibition of each ways, we suggested that there was an interaction between melanogenesis and COX-2/PGE2 pathway. This was characterized by analyzing the COX-2 expression and activity, the expression of tyrosinase and melanin production. Furthermore, we showed that anti-proliferative and proapoptotic effects of UA were mediated through modulation of multiple signaling pathways including Akt and ERK-1/2 proteins. Our study not only uncovers underlying molecular mechanisms of UA action in human melanoma cancer cells but also suggest its great potential as an adjuvant in treatment and cancer prevention. PMID:27262506

  20. Stearoyl-CoA desaturase-1 (SCD1 augments saturated fatty acid-induced lipid accumulation and inhibits apoptosis in cardiac myocytes.

    Hiroki Matsui

    Full Text Available Mismatch between the uptake and utilization of long-chain fatty acids in the myocardium leads to abnormally high intracellular fatty acid concentration, which ultimately induces myocardial dysfunction. Stearoyl-Coenzyme A desaturase-1 (SCD1 is a rate-limiting enzyme that converts saturated fatty acids (SFAs to monounsaturated fatty acids. Previous studies have shown that SCD1-deficinent mice are protected from insulin resistance and diet-induced obesity; however, the role of SCD1 in the heart remains to be determined. We examined the expression of SCD1 in obese rat hearts induced by a sucrose-rich diet for 3 months. We also examined the effect of SCD1 on myocardial energy metabolism and apoptotic cell death in neonatal rat cardiac myocytes in the presence of SFAs. Here we showed that the expression of SCD1 increases 3.6-fold without measurable change in the expression of lipogenic genes in the heart of rats fed a high-sucrose diet. Forced SCD1 expression augmented palmitic acid-induced lipid accumulation, but attenuated excess fatty acid oxidation and restored reduced glucose oxidation. Of importance, SCD1 substantially inhibited SFA-induced caspase 3 activation, ceramide synthesis, diacylglycerol synthesis, apoptotic cell death, and mitochondrial reactive oxygen species (ROS generation. Experiments using SCD1 siRNA confirmed these observations. Furthermore, we showed that exposure of cardiac myocytes to glucose and insulin induced SCD1 expression. Our results indicate that SCD1 is highly regulated by a metabolic syndrome component in the heart, and such induction of SCD1 serves to alleviate SFA-induced adverse fatty acid catabolism, and eventually to prevent SFAs-induced apoptosis.

  1. Fenofibrate, a PPARα agonist, protect proximal tubular cells from albumin-bound fatty acids induced apoptosis via the activation of NF-kB.

    Zuo, Nan; Zheng, Xiaoyu; Liu, Hanzhe; Ma, Xiaoli

    2015-01-01

    Albumin-bound fatty acids is the main cause of renal damage, PPARα is responsible in the metabolism of fatty acids. Previous study found that PPARα played a protective role in fatty acids overload associated tubular injury. The aim of the present study is to investigate whether fenofibrate, a PPARα ligands, could contribute to the renoprotective action in fatty acids overload proximal tubule epithelial cells. We observed in HK-2 cells that fenofibrate significantly inhibited fatty acids bound albumin (FA-BSA) induced up-regulation of MCP-1 and IL-8. Treatment with fenofibrate attenuated renal oxidative stress induced by FA-BSA as evidenced by decreased MDA level, increased SOD activity and catalase, GPx-1 expression. FA-BSA induced apoptosis of HK-2 cells were also obviously prevented by fenofibrate. Furthermore, fenofibrate significantly increased the expression of PPARα mRNA and protein in FA-BSA treated cells. Finally, the activation of NF-kB induced by FA-BSA was markedly suppressed by fenofibrate. Taken together, our study describes a renoprotective role of fenofibrate in fatty acids associated tubular toxicity, and the transcriptional activation of PPARα and suppression of NF-kB were at least partially involved. PMID:26617775

  2. Docosahexaenoic acid induces apoptosis in MCF-7 cells in vitro and in vivo via reactive oxygen species formation and caspase 8 activation.

    Ki Sung Kang

    Full Text Available BACKGROUND: The present study sought to further investigate the in vitro and in vivo anticancer effects of a representative omega-3 fatty acid, docosahexaenoic acid (DHA, with a focus on assessing the induction of oxidative stress and apoptosis as an important mechanism for its anticancer actions. METHODOLOGY/PRINCIPAL FINDINGS: In vitro studies showed that DHA strongly reduces the viability and DNA synthesis of MCF-7 human breast cancer cells in culture, and also promotes cell death via apoptosis. Mechanistically, accumulation of reactive oxygen species and activation of caspase 8 contribute critically to the induction of apoptotic cell death. Co-presence of antioxidants or selective inhibition or knockdown of caspase 8 each effectively abrogates the cytotoxic effect of DHA. Using athymic nude mice as an in vivo model, we found that feeding animals the 5% fish oil-supplemented diet for 6 weeks significantly reduces the growth of MCF-7 human breast cancer cells in vivo through inhibition of cancer cell proliferation as well as promotion of cell death. Using 3-nitrotyrosine as a parameter, we confirmed that the fish oil-supplemented diet significantly increases oxidative stress in tumor cells in vivo. Analysis of fatty acid content in plasma and tissues showed that feeding animals a 5% fish oil diet increases the levels of DHA and eicosapentaenoic acid in both normal and tumorous mammary tissues by 329% and 300%, respectively. CONCLUSIONS/SIGNIFICANCE: DHA can strongly induce apoptosis in human MCF-7 breast cancer cells both in vitro and in vivo. The induction of apoptosis in these cells is selectively mediated via caspase 8 activation. These observations call for further studies to assess the effectiveness of fish oil as a dietary supplement in the prevention and treatment of human breast cancer.

  3. Alpha-picolinic acid,a fungal toxin and mammal apoptosis-inducing agent,elicits hypersensitive-like response and enhances disease resistance in rice

    Hai Kuo ZHANG; Xin ZHANG; Bi Zeng MAO; Qun LI; Zu Hua HE

    2004-01-01

    Alpha-picolinic acid (PA),a metabolite of tryptophan and an inducer of apoptosis in the animal cell,has been reported to be a toxin produced by some of plant fungal pathogens and used in screening for disease resistant mutants. Here,we report that PA is an efficient apoptosis agent triggering cell death of hypersensitive-like response in planta. Confirmed by Fluorescence Activated Cell Sorter (FACS),rice suspension cells and leaves exhibited programmed cell death induced by PA. The PA-induced cell death was associated with the accumulation of reactive oxygen species that could be blocked by diphenylene iodonium chloride,indicating that the generation of reactive oxygen species was NADPHoxidase dependent. We also demonstrated the induction of rice defense-related genes and subsequent resistant enhancement by PA against the rice blast fungus Magnaporthe grisea. Hence,it was concluded that the PA-stimulated defense response likely involves the onset of the hypersensitive response in rice,which also provides a simple eliciting tool for studying apoptosis in the plant cell.

  4. Tauroursodeoxycholate Protects Rat Hepatocytes from Bile Acid-Induced Apoptosis via β1-Integrin- and Protein Kinase A-Dependent Mechanisms

    Annika Sommerfeld

    2015-05-01

    Full Text Available Background/Aims: Ursodeoxycholic acid, which in vivo is rapidly converted into its taurine conjugate, is frequently used for the treatment of cholestatic liver disease. Apart from its choleretic effects, tauroursodeoxycholate (TUDC can protect hepatocytes from bile acid-induced apoptosis, but the mechanisms underlying its anti-apoptotic effects are poorly understood. Methods: These mechanisms were investigated in perfused rat liver and isolated rat hepatocytes. Results: It was found that TUDC inhibited the glycochenodeoxycholate (GCDC-induced activation of the CD95 death receptor at the level of association between CD95 and the epidermal growth factor receptor. This was due to a rapid TUDC-induced β1-integrin-dependent cyclic AMP (cAMP signal with induction of the dual specificity mitogen-activated protein (MAP kinase phosphatase 1 (MKP-1, which prevented GCDC-induced phosphorylation of mitogen-activated protein kinase kinase 4 (MKK4 and c-jun-NH2-terminal kinase (JNK activation. Furthermore, TUDC induced a protein kinase A (PKA-mediated serine/threonine phosphorylation of the CD95, which was recently identified as an internalization signal for CD95. Furthermore, TUDC inhibited GCDC-induced CD95 targeting to the plasma membrane in a β1-integrin-and PKA-dependent manner. In line with this, the β1-integrin siRNA knockdown in sodium taurocholate cotransporting polypeptide (Ntcp-transfected HepG2 cells abolished the protective effect of TUDC against GCDC-induced apoptosis. Conclusion: TUDC exerts its anti-apoptotic effect via a β1-integrin-mediated formation of cAMP, which prevents CD95 activation by hydrophobic bile acids at the levels of JNK activation and CD95 serine/threonine phosphorylation.

  5. Activation of γ-aminobutyric Acid (A) Receptor Protects Hippocampus from Intense Exercise-induced Synapses Damage and Apoptosis in Rats

    Yi Ding; Lan Xie; Cun-Qing Chang; Zhi-Min Chen; Hua Ai

    2015-01-01

    Background:Our previous study has confirmed that one bout of exhaustion (Ex) can cause hippocampus neurocyte damage,excessive apoptosis,and dysfunction.Its initial reason is intracellular calcium overload in hippocampus triggered by N-methyl-D-aspartic acid receptor (NMDAR) over-activation.NMDAR activation can be suppressed by γ-aminobutyric acid (A) receptor (GABAAR).Whether GABAAR can prevent intense exercise-induced hippocampus apoptosis,damage,or dysfunction will be studied in this study.Methods:According to dose test,rats were randomly divided into control (Con),Ex,muscimol (MUS,0.l mg/kg) and bicuculline (BIC,0.5 mg/kg) groups,then all rats underwent once swimming Ex except ones in Con group only underwent training.Intracellular free calcium concentration ([Ca2+]i) was measured by Fura-2-acetoxymethyl ester;glial fibrillary acidic protein (GFAP) and synaptophysin (SYP) immunofluorescence were also performed;apoptosis were displayed by dUTP nick end labeling (TUNEL) stain;endoplasmic reticulum stress-induced apoptosis pathway was detected by Western blotting analysis;Morris water maze was used to detect learning ability and spatial memory.Results:The appropriate dose was 0.1 mg/kg for MUS and 0.5 mg/kg for BIC.Ex group showed significantly increased [Ca2+]i and astrogliosis;TUNEL positive cells and levels of GFAP,B cell lymphoma-2 (Bcl-2) associated X protein (Bax),caspase-3,caspase-12 cleavage,CCAAT/enhancer binding protein homologous protein (CHOP),and p-Jun amino-terminal kinase (p-JNK) in Ex group also raised significantly compared to Con group,while SYP,synapse plasticity,and Bcl-2 levels in Ex group were significantly lower than those in Con group.These indexes were back to normal in MUS group.BIC group had the highest levels of [Ca2+]i,astrogliosis,TUNEL positive cell,GFAP,Bax,caspase-3,caspase-12 cleavage,CHOP,and p-JNK,it also gained the lowest SYP,synapse plasticity,and Bcl-2 levels among all groups.Water maze test showed that Ex group had longer

  6. The natural triterpene maslinic acid induces apoptosis in HT29 colon cancer cells by a JNK-p53-dependent mechanism

    Maslinic acid, a pentacyclic triterpene found in the protective wax-like coating of the leaves and fruit of Olea europaea L., is a promising agent for the prevention of colon cancer. We have shown elsewhere that maslinic acid inhibits cell proliferation to a significant extent and activates mitochondrial apoptosis in colon cancer cells. In our latest work we have investigated further this compound's apoptotic molecular mechanism. We used HT29 adenocarcinoma cells. Changes genotoxicity were analyzed by single-cell gel electrophoresis (comet assay). The cell cycle was determined by flow cytometry. Finally, changes in protein expression were examined by western blotting. Student's t-test was used for statistical comparison. HT29 cells treated with maslinic acid showed significant increases in genotoxicity and cell-cycle arrest during the G0/G1 phase after 72 hours' treatment and an apoptotic sub-G0/G1 peak after 96 hours. Nevertheless, the molecular mechanism for this cytotoxic effect of maslinic acid has never been properly explored. We show here that the anti-tumoral activity of maslinic acid might proceed via p53-mediated apoptosis by acting upon the main signaling components that lead to an increase in p53 activity and the induction of the rest of the factors that participate in the apoptotic pathway. We found that in HT29 cells maslinic acid activated the expression of c-Jun NH2-terminal kinase (JNK), thus inducing p53. Treatment of tumor cells with maslinic acid also resulted in an increase in the expression of Bid and Bax, repression of Bcl-2, release of cytochrome-c and an increase in the expression of caspases -9, -3, and -7. Moreover, maslinic acid produced belated caspase-8 activity, thus amplifying the initial mitochondrial apoptotic signaling. All these results suggest that maslinic acid induces apoptosis in human HT29 colon-cancer cells through the JNK-Bid-mediated mitochondrial apoptotic pathway via the activation of p53. Thus we propose

  7. Protein tyrosine kinase, JNK, and ERK involvement in p seudolaric acid B-induced apoptosis of human breast cancer MCF-7 cells

    Jing-hua YU; Hong-jun WANG; Xiang-ru LI; Shin-ichi TASHIRO; Satoshi ONODERA; Takashi IKEJIMA

    2008-01-01

    Aim:To investigate the apoptotic mechanism ofpseudolaric acid B (PAB) in hu-man breast cancer MCF-7 cells. Methods: 3-(4,5-Dimethylthiazol-2-yl)-2, 5-di-phenyltetrazolium bromide analysis and morphological changes were applied to detect apoptosis. The percentage of apoptotic and necrotic cells were calculated by the lactate dehydrogenase activity-based cytotoxicity assay, and the protein expression was examined by Western blot analysis. Results: PAB and/or the mitogen-activated protein kinases, including p38, c-Jun-N-terrninal kinase (JNK) and extracellular signal-regulated kinase (ERK), did not participate in necrosis. P38 had no obvious function on apoptosis after 4 μmol/L PAB treatment for 36 h, but PAB induced JNK phosphorylation and inhibited ERK phosphorylation in the apoptotic process. In this study the inhibitor of protein tyrosine kinase (PTK) genistein inverted the inhibitory effect of PAB, instead promoting the survival of MCF-7 cells. Like genistein, another PTK inhibitor AG1024 had a similar ef-fect on PAB-treated MCF-7 cells, indicating that PAB activated PTK to induce apoptosis. Together with PAB, genistein increased the expression of p-ERK, and decreased the expressions of JNK and p-JNK in PAB-treated MCF-7 cells at 36 h. And it is considered that the p-ERK and p-JNK were active patterns of ERK and JNK, respectively. Conclusion: PTK were upstream of ERK and JNK, and PTK induced apoptosis through activating JNK and inactivating ERK in PAB-treated MCF-7 cells.

  8. The dietary hydrolysable tannin punicalagin releases ellagic acid that induces apoptosis in human colon adenocarcinoma Caco-2 cells by using the mitochondrial pathway.

    Larrosa, Mar; Tomás-Barberán, Francisco A; Espín, Juan Carlos

    2006-09-01

    Polyphenol-rich dietary foodstuffs have attracted attention due to their cancer chemopreventive and chemotherapeutic properties. Ellagitannins (ETs) belong to the so-called hydrolysable tannins found in strawberries, raspberries, walnuts, pomegranate, oak-aged red wine, etc. Both ETs and their hydrolysis product, ellagic acid (EA), have been reported to induce apoptosis in tumour cells. Ellagitannins are not absorbed in vivo but reach the colon and release EA that is metabolised by the human microflora. Our aim was to investigate the effect of a dietary ET [pomegranate punicalagin (PUNI)] and EA on human colon cancer Caco-2 and colon normal CCD-112CoN cells. Both PUNI and EA provoked the same effects on Caco-2 cells: down-regulation of cyclins A and B1 and upregulation of cyclin E, cell-cycle arrest in S phase, induction of apoptosis via intrinsic pathway (FAS-independent, caspase 8-independent) through bcl-XL down-regulation with mitochondrial release of cytochrome c into the cytosol, activation of initiator caspase 9 and effector caspase 3. Neither EA nor PUNI induced apoptosis in normal colon CCD-112CoN cells (no chromatin condensation and no activation of caspases 3 and 9 were detected). In the case of Caco-2 cells, no specific effect can be attributed to PUNI since it was hydrolysed in the medium to yield EA, which entered into the cells and was metabolised to produce dimethyl-EA derivatives. Our study suggests that the anticarcinogenic effect of dietary ETs could be mainly due to their hydrolysis product, EA, which induced apoptosis via mitochondrial pathway in colon cancer Caco-2 cells but not in normal colon cells. PMID:16426830

  9. Apoptosis-induced cell death due to oleanolic acid in HaCaT keratinocyte cells--a proof-of-principle approach for chemopreventive drug development.

    George, V Cijo; Kumar, D R Naveen; Suresh, P K; Kumar, R Ashok

    2012-01-01

    Oleanolic acid (OA) is a naturally occurring triterpenoid in food materials and is a component of the leaves and roots of Olea europaea, Viscum album L., Aralia chinensis L. and more than 120 other plant species. There are several reports validating its antitumor activity against different cancer cells apart from its hepatoprotective activity. However, antitumor activity against skin cancer has not been studied well thus far. Hence the present study of effects of OA against HaCaT (immortalized keratinocyte) cells--a cell-based epithelial model system for toxicity/ethnopharmacology-based studies--was conducted. Radical scavenging activity (DPPH·) and FRAP were determined spectrophotometrically. Proliferation was assessed by XTT assay at 24, 48 and 72 hrs with exposure to various concentrations (12.5-200 μM) of OA. Apoptotic induction potential of OA was demonstrated using a cellular DNA fragmentation ELISA method. Morphological studies were also carried out to elucidate its antitumor potential. The results revealed that OA induces apoptosis by altering cellular morphology as well as DNA integrity in HaCaT cells in a dose-dependent manner, with comparatively low cytotoxicity. The moderate toxicity observed in HaCaT cells, with induction of apoptosis, possibly suggests greater involvement of programmed-cell death-mediated mechanisms. We conclude that OA has relatively low toxicity and has the potential to induce apoptosis in HaCaT cells and hence provides a substantial and sound scientific basis for further validation studies. PMID:22901164

  10. Dopamine-induced apoptosis in human neuronal cells: inhibition by nucleic acides antisense to the dopamine transporter

    Human neuroblastoma NMB cells take up [3H]dopamine in a selective manner indicating that dopamine transporters are responsible for this uptake. These cells were therefore used as a model to study dopamine neurotoxicity, and to elucidate the role of dopamine transporters in controlling cell death. Treatment with 0.05-0.4 mM dopamine changed cells' morphology within 4 h, accompanied by retraction of processes, shrinkage, apoptosis-like atrophy, accumulation of apoptotic particles, DNA fragmentation and cell death. Cycloheximide inhibited dopamine's effect, suggesting that induction of apoptosis by dopamine was dependent upon protein synthesis. Dopamine cytotoxicity, monitored morphologically by flow cytometric analysis, and by lactate dehydrogenase released, was blocked by cocaine but not by the noradrenaline and serotonin uptake blockers desimipramine and imipramine, respectively. Attempting to inhibit dopamine transport and toxicity in a drug-free and highly selective way, three 18-mer dopamine transporter antisense phosphorothioate oligonucleotides (numbers 1, 2 and 3) and a new plasmid vector expressing the entire rat dopamine transporter complementary DNA in the antisense orientation were prepared and tested. Antisense phosphorothioate oligonucleotide 3 inhibited [3H]dopamine uptake in a time- and dose-dependent manner. Likewise, transient transfection of NMB cells with the plasmid expressing dopamine transporter complementary DNA in the antisense orientation partially blocked [3H]dopamine uptake. Antisense phosphorothioate oligonucleotide 3 also decreased, dose-dependently, the toxic effect of dopamine and 6-hydroxydopamine. Western blot analysis with newly prepared anti-human dopamine transporter antibodies showed that antisense phosphorothioate oligonucleotide 3 decreased the transporter protein level. These studies contribute to better understand the mechanism of dopamine-induced apoptosis and neurotoxicity. (Copyright (c) 1996 Elsevier Science B

  11. In vitro study on arsenic sulfide (realgar)-induced apoptosis of retinoic acid susceptible or resistant acute promyelocytic leukemia cell lines

    CHEN Si-yu; LIU Shan-xi; LI Xin-min

    2002-01-01

    Objective: To further understand the possible mechanisms of arsenic sulfide (realgar) in the treatment of acute promyelocytic leukemia (APL). Methods: All-trans retinoic acid (ATRA)-susceptible APL cell line (NB4 cells) and ATRA-resistant APL cell line (MR2 subclone) were used as models in vitro. At various times after incubated with various concentrations of realgar, NB4 and MR2 cells were observed by cell viability, cell proliferation and cell morphology; cell cycle and the expression of Annexin V were assayed by flow cytometry. Results: Cell viability and proliferation of NB4 and MR2 cells were inhibited after the treatment,to some extent, in a dose and time dependent manner. 177-711 μg/L of realgar treated NB4 and MR2 cell presented morphologically some features of apoptotic cells such as intact cell membrane, chromatin condensation and nuclear fragmentation, apoptosis body could be found by electron microscopy as well. Sub-G1 ceils andcell cycle arrest were observed by flow cytometry. The proportion of Annexin V -FITC+/PI cells, which represent apoptotic cells, was up-regulated. Conclusion: Realgar could induce apoptosis of acute promyelocytic leukemia cell despite its susceptibility to retinoic acid in the way that may be different from retinoic acid.

  12. Ganoderic acid DM, a natural triterpenoid, induces DNA damage, G1 cell cycle arrest and apoptosis in human breast cancer cells.

    Wu, Guo-Sheng; Lu, Jin-Jian; Guo, Jia-Jie; Li, Ying-Bo; Tan, Wen; Dang, Yuan-Ye; Zhong, Zhang-Feng; Xu, Zeng-Tao; Chen, Xiu-Ping; Wang, Yi-Tao

    2012-03-01

    Ganoderic acid DM (GADM) is a triterpenoid isolated from Ganoderma lucidum, a well-known edible medicinal mushroom. In the present study, we found that GADM effectively inhibited cell proliferation and colony formation in MCF-7 human breast cancer cells, which was much stronger than that of MDA-MB-231 breast cancer cells. GADM both concentration- and time-dependently mediated G1 cell cycle arrest and significantly decreased the protein level of CDK2, CDK6, cycle D1, p-Rb and c-Myc in MCF-7 cells. Moreover, GADM obviously induced DNA fragmentation and cleavage of PARP which are the characteristics of apoptosis and decreased the mitochondrial membrane potential in MCF-7 cells. Besides, we also showed that GADM elicited DNA damage as measured by comet assay which is a sensitive method for DNA damage detection. γ-H2AX, a marker of DNA damage, was also slightly up-regulated after treated with GADM for 6h, suggesting that the G1 cell cycle arrest and apoptosis induced by GADM may be partially resulted from GADM-induced DNA damage. These results have advanced our current understandings of the anti-cancer mechanisms of GADM. PMID:22178684

  13. Quinovic acid glycosides purified fraction from Uncaria tomentosa induces cell death by apoptosis in the T24 human bladder cancer cell line.

    Dietrich, Fabrícia; Kaiser, Samuel; Rockenbach, Liliana; Figueiró, Fabrício; Bergamin, Letícia Scussel; da Cunha, Fernanda Monte; Morrone, Fernanda Bueno; Ortega, George González; Battastini, Ana Maria Oliveira

    2014-05-01

    Bladder cancer is the second most prevalent malignancy in the genitourinary tract and remains a therapeutic challenge. In the search for new treatments, researchers have attempted to find compounds with low toxicity. With this goal in mind, Uncaria tomentosa is noteworthy because the bark and root of this species are widely used in traditional medicine and in adjuvant therapy for the treatment of numerous diseases. The objective of this study was to investigate the antitumor effect of one purified bioactive fraction of U.tomentosa bark on cell proliferation in two human bladder cancer cell lines, T24 and RT4. Quinovic acid glycosides purified fraction (QAPF) of U.tomentosa decreased the growth and viability of both T24 and RT4 cell lines. In T24 cells, QAPF induced apoptosis by activating caspase-3 and NF-κB. Further study showed that this fraction does not induce cell cycle arrest and does not alter PTEN and ERK levels. In conclusion, we demonstrated that QAPF of U.tomentosa has a potent inhibitory effect on the growth of human bladder cancer cell lines by inducing apoptosis through modulation of NF-κB, and we suggest that QAPF may become a potential therapeutic agent for the prevention and/or treatment of this cancer. PMID:24607820

  14. Retinoids induce Nur77-dependent apoptosis in mouse thymocytes.

    Kiss, Beáta; Tóth, Katalin; Sarang, Zsolt; Garabuczi, Éva; Szondy, Zsuzsa

    2015-03-01

    Nur77 is a transcription factor, which plays a determinant role in mediating T cell receptor-induced cell death of thymocytes. In addition to regulation of transcription, Nur77 contributes to apoptosis induction by targeting mitochondria, where it can convert Bcl-2, an anti-apoptotic protein into a proapoptotic molecule. Previous studies have demonstrated that retinoids are actively produced in the mouse thymus and can induce a transcription-dependent apoptosis in mouse thymocytes. Here we show that retinoic acids induce the expression of Nur77, and retinoid-induced apoptosis is completely dependent on Nur77, as retinoids were unable to induce apoptosis in Nur77 null thymocytes. In wild-type thymocytes retinoids induced enhanced expression of the apoptosis-related genes FasL, TRAIL, NDG-1, Gpr65 and Bid, all of them in a Nur77-dependent manner. The combined action of these proteins led to Caspase 8-dependent Bid cleavage in the mitochondria. In addition, we could demonstrate the Nur77-dependent induction of STAT1 leading to enhanced Bim expression, and the mitochondrial translocation of Nur77 leading to the exposure of the Bcl-2/BH3 domain. The retinoid-induced apoptosis was dependent on both Caspase 8 and STAT1. Our data together indicate that retinoids induce a Nur77-dependent cell death program in thymocytes activating the mitochondrial pathway of apoptosis. PMID:25576519

  15. Cytotoxic and apoptosis-inducing effect of ent-15-oxo-kaur-16-en-19-oic acid, a derivative of grandiflorolic acid from Espeletia schultzii.

    Ruiz, Yarimar; Rodrígues, Juan; Arvelo, Francisco; Usubillaga, Alfredo; Monsalve, Mariugenia; Diez, Nardy; Galindo-Castro, Iván

    2008-01-01

    ent-Kaurenic acid and many natural derivatives of this diterpene are known to have interesting biological properties. ent-15-Oxo-kaur-16-en-19-oic acid can be easily obtained from grandiflorolic acid which was first isolated from Espeletia grandiflora. The present work describes the proapoptotic effect of ent-15-oxo-kaur-16-en-19-oic acid on the human prostate carcinoma epithelial cell line PC-3 as evidenced by the changes in the expression level of proteins associated with the execution and regulation of apoptosis. Cell viability was affected upon exposure to the compound, the IC(50) were determined as 3.7 microg/ml, which is 4 times lower than that corresponding to a primary cell culture of fibroblasts (14.8 microg/mL). Through Western blot analysis, active forms of caspace-3 associated with the specific proteolysis of Poly(ADP-ribose) polymerase (PARP) were detected. Reduced levels of the antiapoptotic protein Bcl-2, as well as the appearance of internucleosomal DNA fragmentation, were also demonstrated. Thus, ent-15-oxo-kaur-16-en-19-oic acid may be a promising lead compound for new chemopreventive strategies, alone or in combination with traditional chemotherapy agents to overcome drug resistance in tumoral cells. PMID:17869315

  16. Linoleic acid derivative DCP-LA protects neurons from oxidative stress-induced apoptosis by inhibiting caspase-3/-9 activation.

    Yaguchi, Takahiro; Fujikawa, Hirokazu; Nishizaki, Tomoyuki

    2010-05-01

    The present study aimed at understanding the effect of the linoleic acid derivative 8-[2-(2-pentyl-cyclopropylmethyl)-cyclopropyl]-octanoic acid (DCP-LA) on oxidative stress-induced neuronal death. Sodium nitroprusside (SNP; 1 mM) reduced viability of cultured rat cerebral cortical neurons to 50% of basal levels, but DCP-LA significantly prevented the SNP effect in a concentration (1-100 nM)-dependent manner. In addition, DCP-LA (100 nM) rescued neurons from SNP-induced degradation. SNP (1 mM) activated caspase-3 and -9 in cultured rat cerebral cortical neurons, but DCP-LA (100 nM) abolished the caspase activation. For a mouse model of middle cerebral artery occlusion, oral administration with DCP-LA (1 mg/kg) significantly diminished degraded area due to cerebral infarction. The results of the present study, thus, demonstrate that DCP-LA protects neurons at least in part from oxidative stress-induced apoptosis by inhibiting activation of caspase-3/-9. PMID:20099079

  17. Effect of pH on radiation-induced apoptosis

    Purpose/Objective: The effect of environmental pH on the radiation-induced apoptosis in tumor cells in vitro was investigated. Materials and Methods: SCK mammary adenocarcinoma cells of A/J mice were irradiated with γ-rays using a 137Cs irradiator and incubated in media of different pHs. After incubation at 37 degree sign C for 24-120 hrs., the extent of apoptosis was determined using agarose gel electrophoresis of DNA, in situ TUNEL staining, flow cytometry, and release of 3H from 3H-thymidine labeled cells. The membrane integrity, using the trypan blue exclusion method, and the clonogenicity of the cells were also determined. Results: Irradiation with 2-12 Gy of γ-rays induced apoptosis in pH 7.5 medium within 48 hrs. The radiation-induced apoptosis progressively declined as the medium pH was lowered so that little apoptosis occurred in 48 hrs. after irradiation with 12 Gy in pH 6.6 medium. However, when the cells were irradiated and incubated for 48 hrs. in pH 6.6 medium and then medium was replaced with pH 7.5 medium, apoptosis promptly occurred. Apoptosis also occurred even in pH 6.6 medium when the cells were irradiated and maintained in pH 7.5 medium for 8 hrs. or longer post-irradiation before incubation in pH 6.6 medium. Conclusion: An acidic environment markedly suppresses radiation-induced apoptosis probably by suppressing the expression of initial signals responsible for irradiation-induced apoptosis. Indications are that the signals persist in an acidic environment and trigger apoptosis when the environmental acidity is eased. Our results suggest that the acidic environment in human tumors may inhibit the apoptosis after irradiation. However, apoptosis may be triggered when reoxygenation occurs after irradiation, and thus, the intratumor environment becomes less acidic after irradiation. Not only the change in pO2 but the change in pH during the course of fractionated radiotherapy may greatly influence the outcome of the treatment

  18. LRD-22, a novel dual dithiocarbamatic acid ester, inhibits Aurora-A kinase and induces apoptosis and cell cycle arrest in HepG2 cells

    In this study we investigated the antitumor activity of the novel dual dithiocarbamatic acid ester LRD-22 in vitro and in vivo. Several cancer cell lines were employed to determine the effect of LRD-22 on cell growth, and the MTT assay showed there was a significant decrease in viable tumor cell numbers in the presence of LRD-22, especially in the HepG2 cell line. Colony formation assay also showed LRD-22 strongly inhibits HepG2 cell growth. Evaluation of the mechanism involved showed that inhibitory effects of LRD-22 on cell growth are due to induction of apoptosis and G2/M arrest. LRD-22 inhibited Aurora-A phosphorylation at Thr288 and subsequently impaired p53 phosphorylation at Ser315 which was associated with the proteasome degradation pathway. Tumor suppressor protein p53 is stabilized by this mechanism and accumulates through inhibition of Aurora-A kinase activity via treatment with LRD-22. In vivo study of HepG2 xenograft in nude mice also shows LRD-22 suppresses tumor growth at a concentration of 5 mg/kg without animals suffering loss of body weight. In conclusion, our results demonstrate LRD-22 acts as an Aurora-A kinase inhibitor to induce apoptosis and inhibit proliferation in HepG2 cells, and should be considered as a promising targeting agent for HCC therapy. - Highlights: • LRD-22 significantly inhibits cancer cell growth, especially in the HepG2 cell line. • The inhibitory effect of LRD-22 is due to induction of apoptosis and cell cycle arrest. • LRD-22 inhibits Aurora-A phosphorylation which results in subsequent impairment of the p53 pathway. • LRD-22 suppresses tumor growth in xenograft mice without body weight loss

  19. LRD-22, a novel dual dithiocarbamatic acid ester, inhibits Aurora-A kinase and induces apoptosis and cell cycle arrest in HepG2 cells

    Wang, Huiling; Li, Ridong [State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, Beijing (China); Li, Li [Department of Cell Biology, School of Basic Medical Sciences, Peking University, Beijing (China); Ge, Zemei [State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, Beijing (China); Zhou, Rouli, E-mail: rlzhou@bjmu.edu.cn [Department of Cell Biology, School of Basic Medical Sciences, Peking University, Beijing (China); Li, Runtao, E-mail: lirt@bjmu.edu.cn [State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, Beijing (China)

    2015-02-27

    In this study we investigated the antitumor activity of the novel dual dithiocarbamatic acid ester LRD-22 in vitro and in vivo. Several cancer cell lines were employed to determine the effect of LRD-22 on cell growth, and the MTT assay showed there was a significant decrease in viable tumor cell numbers in the presence of LRD-22, especially in the HepG2 cell line. Colony formation assay also showed LRD-22 strongly inhibits HepG2 cell growth. Evaluation of the mechanism involved showed that inhibitory effects of LRD-22 on cell growth are due to induction of apoptosis and G2/M arrest. LRD-22 inhibited Aurora-A phosphorylation at Thr{sub 288} and subsequently impaired p53 phosphorylation at Ser{sub 315} which was associated with the proteasome degradation pathway. Tumor suppressor protein p53 is stabilized by this mechanism and accumulates through inhibition of Aurora-A kinase activity via treatment with LRD-22. In vivo study of HepG2 xenograft in nude mice also shows LRD-22 suppresses tumor growth at a concentration of 5 mg/kg without animals suffering loss of body weight. In conclusion, our results demonstrate LRD-22 acts as an Aurora-A kinase inhibitor to induce apoptosis and inhibit proliferation in HepG2 cells, and should be considered as a promising targeting agent for HCC therapy. - Highlights: • LRD-22 significantly inhibits cancer cell growth, especially in the HepG2 cell line. • The inhibitory effect of LRD-22 is due to induction of apoptosis and cell cycle arrest. • LRD-22 inhibits Aurora-A phosphorylation which results in subsequent impairment of the p53 pathway. • LRD-22 suppresses tumor growth in xenograft mice without body weight loss.

  20. Activation of Notch1 inhibits medial edge epithelium apoptosis in all-trans retinoic acid-induced cleft palate in mice.

    Zhang, Yadong; Dong, Shiyi; Wang, Weicai; Wang, Jianning; Wang, Miao; Chen, Mu; Hou, Jinsong; Huang, Hongzhang

    2016-08-26

    Administration of all-trans retinoic acid (atRA) on E12.0 (embryonic day 12.0) leads to failure of medial edge epithelium (MEE) disappearance and cleft palate. However, the molecular mechanism underlying the relationship between atRA and MEE remains to be identified. In this study, atRA (200 mg/kg) administered by gavage induced a 75% incidence of cleft palate in C57BL/6 mice. Notch1 was up-regulated in MEE cells in the atRA-treated group compared with the controls at E15.0, together with reduced apoptosis and elevated proliferation. Next, we investigated the mechanisms underlying atRA, Notch1 and MEE degradation in palate organ culture. Our results revealed that down-regulation of Notch1 partially rescued the inhibition of atRA-induced palate fusion. Molecular analysis indicated that atRA increased the expression of Notch1 and Rbpj and decreased the expression of P21. In addition, depletion of Notch1 expression decreased the expression of Rbpj and increased the expression of P21. Moreover, inhibition of Rbpj expression partially reversed atRA-induced MEE persistence and increased P21 expression. These findings demonstrate that atRA inhibits MEE degradation, which in turn induces a cleft palate, possibly through the Notch1/RBPjk/P21 signaling pathway. PMID:27343556

  1. Asiatic acid, a pentacyclic triterpene in Centella asiatica, attenuates glutamate-induced cognitive deficits in mice and apoptosis in SH-SY5Y cells

    Min-fang XU; Yu-yun XIONG; Jian-kang LIU; Jin-jun QIAN; Li ZHU; Jing GAO

    2012-01-01

    To investigate whether asiatic acid (AA),a pentacyclic triterpene in Centella asiatica,exerted neuroprotective effects in vitro and in vivo,and to determine the underlying mechanisms.Methods:Human neuroblastoma SH-SY5Y cells were used for in vitro study.Cell viability was determined with the MTT assay.Hoechst 33342 staining and flow cytometry were used to examine the apoptosis.The mitochondrial membrane potential (MMP) and reactive oxygen species (ROS) were measured using fluorescent dye.PGC-1α and Sift1 levels were examined using Western blotting.Neonatal mice were given monosodium glutamate (2.5 mg/g) subcutaneously at the neck from postnatal day (PD) 7 to 13,and orally administered with AA on PD 14 daily for 30 d.The learning and memory of the mice were evaluated with the Morris water maze test.HE staining was used to analyze the pyramidal layer structure in the CA1 and CA3 regions.Results:Pretreatment of SH-SY5Y cells with AA (0.1-100 nmol/L) attenuated toxicity induced by 10 mmol/L glutamate in a concentration-dependent manner.AA 10 nmol/L significantly decreased apoptotic cell death and reduced reactive oxygen species (ROS),stabilized the mitochondrial membrane potential (MMP),and promoted the expression of PGC-1α and Sirt1.In the mice models,oral administration of AA (100 mg/kg) significantly attenuated cognitive deficits in the Morris water maze test,and restored lipid peroxidation and glutathione and the activity of SOD in the hippocampus and cortex to the control levels.AA (50 and 100 mg/kg) also attenuated neuronal damage of the pyramidal layer In the CA1 and CA3 regions.Conclusion:AA attenuates glutamate-induced cognitive deficits of mice and protects SH-SY5Y cells against glutamate-induced apoptosis in vitro.

  2. Arsenic trioxide and all-trans retinoic acid target NPM1 mutant oncoprotein levels and induce apoptosis in NPM1-mutated AML cells.

    Martelli, Maria Paola; Gionfriddo, Ilaria; Mezzasoma, Federica; Milano, Francesca; Pierangeli, Sara; Mulas, Floriana; Pacini, Roberta; Tabarrini, Alessia; Pettirossi, Valentina; Rossi, Roberta; Vetro, Calogero; Brunetti, Lorenzo; Sportoletti, Paolo; Tiacci, Enrico; Di Raimondo, Francesco; Falini, Brunangelo

    2015-05-28

    Nucleophosmin (NPM1) mutations represent an attractive therapeutic target in acute myeloid leukemia (AML) because they are common (∼30% AML), stable, and behave as a founder genetic lesion. Oncoprotein targeting can be a successful strategy to treat AML, as proved in acute promyelocytic leukemia by treatment with all-trans retinoic acid (ATRA) plus arsenic trioxide (ATO), which degrade the promyelocytic leukemia (PML)-retinoic acid receptor fusion protein. Adjunct of ATRA to chemotherapy was reported to be beneficial for NPM1-mutated AML patients. Leukemic cells with NPM1 mutation also showed sensibility to ATO in vitro. Here, we explore the mechanisms underlying these observations and show that ATO/ATRA induce proteasome-dependent degradation of NPM1 leukemic protein and apoptosis in NPM1-mutated AML cell lines and primary patients' cells. We also show that PML intracellular distribution is altered in NPM1-mutated AML cells and reverted by arsenic through oxidative stress induction. Interestingly, similarly to what was described for PML, oxidative stress also mediates ATO-induced degradation of the NPM1 mutant oncoprotein. Strikingly, NPM1 mutant downregulation by ATO/ATRA was shown to potentiate response to the anthracyclin daunorubicin. These findings provide experimental evidence for further exploring ATO/ATRA in preclinical NPM1-mutated AML in vivo models and a rationale for exploiting these compounds in chemotherapeutic regimens in clinics. PMID:25795919

  3. Apoptosis and signalling in acid sphingomyelinase deficient cells

    Sillence Dan J

    2001-11-01

    Full Text Available Abstract Background Recent evidence suggests that the activation of a non-specific lipid scramblase during apoptosis induces the flipping of sphingomyelin from the cell surface to the cytoplasmic leaftet of the plasma membrane. Inner leaflet sphingomyelin is then cleaved to ceramide by a neutral sphingomyelinase. The production of this non-membrane forming lipid induces blebbing of the plasma membrane to aid rapid engulfment by professional phagocytes. However contrary evidence suggests that cells which are deficient in acid sphingomyelinase are defective in apoptosis signalling. This data has been interpreted as support for the activation of acid sphingomyelinase as an early signal in apoptosis. Hypothesis An alternative explanation is put forward whereby the accumulation of intracellular sphingomyelin in sphingomyelinase deficient cells leads to the formation of intracellular rafts which lead to the sequestration of important signalling molecules that are normally present on the cell surface where they perform their function. Testing the hypothesis It is expected that the subcellular distribution of important signalling molecules is altered in acid sphingomyelinase deficient cells, leading to their sequestration in late endosomes / lysosomes. Other sphingolipid storage diseases such as Niemann-Pick type C which have normal acid sphingomyelinase activity would also be expected to show the same phenotype. Implications of the hypothesis If true the hypothesis would provide a mechanism for the pathology of the sphingolipid storage diseases at the cellular level and also have implications for the role of ceramide in apoptosis.

  4. Apoptosis in vascular cells induced by cold atmospheric plasma treatment

    Sladek, Raymond; Stoffels, Eva

    2006-10-01

    Apoptosis is a natural mechanism of cellular self-destruction. It can be triggered by moderate, yet irreversible damage. Apoptosis plays a major role in tissue renewal. Artificial apoptosis induction will become a novel therapy that meets all requirements for tissue-saving surgery. Diseased tissues can disappear without inflammation and scarring. This is particularly important in treatment of blockages in body tracts (e.g. cardiovascular diseases). Artificial induction of apoptosis can be achieved by means of cold plasma treatment. In this work an atmospheric micro-plasma operated in helium/air has been used to induce apoptosis in vascular cells. Parametric studies of apoptosis induction have been conducted; the efficiency is almost 100%. The apoptotic factors are ROS/RNS (reactive oxygen and nitrogen species). Their densities in the plasma have been measured by mass spectrometry. For apoptosis induction, RNS seem to be more important than ROS, because of their relative abundance. Moreover, addition of a ROS scavenger (ascorbic acid) to the cell culture medium does not reduce the occurrence of apoptosis. Cold plasma is a very efficient tool for fundamental studies of apoptosis, and later, for controlled tissue removal in vivo.

  5. Ameliorative effects of bombesin and neurotensin on trinitrobenzene sulphonic acid-induced colitis, oxidative damage and apoptosis in rats

    2008-01-01

    AIM: To investigate the effects of bombesin (BBS) and neurotensin (NTS) on apoptosis and colitis in an ulcerative colitis model. METHODS: In this study, a total of 50 rats were divided equally into 5 groups. In the control group, no colitis induction or drug administration was performed. Colitis was induced in all other groups. Following the induction of colitis, BBS, NTS or both were applied to three groups of rats. The remaining group (colitis group) received no treatment. On the 11th d after induction of colitis and drug treatment, blood samples were collected for TNF-α and IL-6 level studies. Malondialdehyde (MDA), carbonyl, myeloperoxidase (MPO) and caspase-3 activities, as well as histopathological findings, evaluated in colonic tissues. RESULTS: According to the macroscopic and microscopic findings, the study groups treated with BBS,NTS and BBS+NTS showed significantly lower damage and inflammation compared with the colitis group (macroscopic score,2.1±0.87,3.7±0.94 and 2.1±0.87 vs 7.3 ± 0.94; microscopic score,2.0 ±0.66,3.3±0.82 and 1.8±0.63 vs 5.2±0.78,P<0.01=.TNF-αand IL-6 levels were increased significantly in all groups compared with the control group. These increases were significantly smaller in the BBS,NTS and BBS+NTS groups compared with the colitis group (TNF-α levels,169.69±53.56,245.86±64.85 and 175.54 4±42.19vs 556.44±49.82; IL-6 levels,443.30±53.99,612.80±70.39 and 396.80±78.43 vs 1505.90±222.23,P<0.05=.The colonic MPO and MDA levels were significantly lower in control, BBS, NTS and BBS+NTS groups than in the colitis group (MPO levels,24.36±8.10,40.51±8.67 and 25.83±6.43 vs 161.47±38.24; MDA levels,4.70±1.41,6.55±1.12 and 4.51±0.54 vs15.60±1.88,P<0.05=.Carbonyl content and caspase-3 levels were higher in the colitis and NTS groups than in control, BBS and BBS+NTS groups (carbonyl levels,553.99±59.58and 336.26±35.72 vs 209.76±30.92,219.76±25.77and 220.34 36.95; caspase-3 levels,451.70±68.27and 216.20

  6. Glutathione, N-acetylcysteine and lipoic acid down-regulate starvation-induced apoptosis, RANKL/OPG ratio and sclerostin in osteocytes: involvement of JNK and ERK1/2 signalling.

    Fontani, Filippo; Marcucci, Gemma; Iantomasi, Teresa; Brandi, Maria Luisa; Vincenzini, Maria Teresa

    2015-04-01

    Osteocyte apoptosis due to microdamage and/or oxidative stress is related to increased local bone turnover and resorption observed in various bone diseases. Previous data on osteoblasts and osteoclasts have linked reactive oxygen species and antioxidants to bone remodelling. This study performs a comprehensive analysis on the effect of antioxidants such as glutathione (GSH), N-acetylcysteine and lipoic acid (LA) on starvation-induced osteocyte apoptosis and on cytokines involved in bone remodelling such as the receptor activator kB ligand (RANKL), osteoprotegerin (OPG) and sclerostin. For this study, apoptosis was induced by serum starvation in a murine osteocyte-like cell line MLO-Y4; this condition mimics in part osteocyte apoptosis due to microdamage. The results show that starvation-induced apoptosis and expression of RANKL, OPG and sclerostin are redox regulated processes. All antioxidants are able to inhibit the apoptosis due to starvation. They down-regulate the expression and the release of RANKL, the expression of sclerostin and RANKL/OPG ratio, whereas they only in part up-regulate OPG expression. Antioxidants mediate their effect on starvation-induced apoptosis by JNK signalling and on cytokine expression by both JNK and ERK1/2 activities. This study shows the possible involvement of biological antioxidants such as GSH and LA on redox regulated mechanisms related to apoptosis and expression of cytokines involved in bone remodelling. Moreover, it suggests that both JNK and ERK1/2 may be useful biological targets for drugs affecting bone diseases associated with increased oxidative stress. PMID:25660312

  7. Expression of lysophosphatidic acid receptor 1 and relation with cell proliferation, apoptosis, and angiogenesis on preneoplastic changes induced by cadmium chloride in the rat ventral prostate.

    Riánsares Arriazu

    Full Text Available BACKGROUND: Lysophosphatidic acid (LPA is a phospholipid growth factor involved in cell proliferation, differentiation, migration, inflammation, angiogenesis, wound healing, cancer invasion, and survival. This study was directed to evaluate the immunoexpression of LPA-1, cell proliferation, apoptosis, and angiogenesis markers in preneoplastic lesions induced with cadmium chloride in rat prostate. METHODS: The following parameters were calculated in ventral prostate of normal rats and rats that received Cd in drinking water during 24 months: percentages of cells immunoreactive to LPA-1 (LILPA1, PCNA (LIPCNA, MCM7 (LIMCM7, ubiquitin (LIUBI, apoptotic cells (LIAPO, and p53 (LIp53; volume fraction of Bcl-2 (VFBcl-2; and length of microvessels per unit of volume (LVMV/mm3. Data were analyzed using Student's t-test and Pearson correlation test. RESULTS: The LILPA1 in dysplastic lesions and normal epithelium of Cd-treated rats was significantly higher than those in the control group. Markers of proliferation were significantly increased in dysplastic lesions, whereas some apoptotic markers were significantly decreased. No significant differences between groups were found in VFBcl-2. Dysplastic lesions showed a significant increase of LIp53. The length of microvessels per unit of volume was elevated in dysplastic acini. Statistically significant correlations were found only between LILPA1 and LIUBI. CONCLUSIONS: Our results suggest that LPA-1 might be implicated in dysplastic lesions induced by cadmium chloride development. More studies are needed to confirm its potential contribution to the disease.

  8. Gallic acid induces apoptosis and enhances the anticancer effects of cisplatin in human small cell lung cancer H446 cell line via the ROS-dependent mitochondrial apoptotic pathway.

    Wang, Ruixuan; Ma, Lijie; Weng, Dan; Yao, Jiahui; Liu, Xueying; Jin, Faguang

    2016-05-01

    Small cell lung cancer (SCLC) is the most aggressive lung cancer subtype and accounts for more than 15% of all lung cancer cases. Cisplatin [cis-diamminedichloroplatinum (CDDP)]-based combination chemotherapy is the cornerstone for all stages of SCLC. However, acquired multidrug resistance (MDR) and intolerable toxicities lead to a high mortality rate in SCLC patients. Gallic acid [3,4,5-trihydroxybenzoic acid (GA)] is a natural botanic phenolic compound which can induce cell apoptosis in several types of cancers. In the present study, we aimed to explore the anticancer effects of GA on human SCLC H446 cells and its promotive effects on the anticancer activities of cisplatin. The viability of the H446 cells was analyzed by MTT assay. Morphological changes in the H446 cells were observed under an inverted microscope. Apoptosis induction was determined by Annexin V-fluorescein isothiocyanate (FITC)/propidium iodide (PI) staining. The level of reactive oxygen species (ROS) was assessed by 2'7'-dichlorofluorescein diacetate (DCFH‑DA), mitochondrial membrane potential (MMP) by JC-1, and western blotting was used to examine the expression of mitochondrial apoptosis-related proteins. The results showed that both GA and cisplatin changed the morphology, inhibited the growth and induced apoptosis in the H446 cells by inducing generation of ROS, disruption of MMP, downregulation of XIAP expression, and upregulation of Bax, Apaf-1, DIABLO and p53 expression. More importantly, GA combined with cisplatin exhibited synergistic effects on inducing of these pro-apoptotic mediators and modulating the activation of apoptosis-related molecules. However, inhibition of the generation of ROS by N-acetyl-l-cysteine (NAC), a specific ROS inhibitor, reversed the cell apoptosis induced by cisplatin combined with GA. In conclusion, the results from the present study revealed that GA exhibited an anticancer effect on human SCLC H446 cells and enhanced the antitumor activities of cisplatin

  9. microRNA-34a-Upregulated Retinoic Acid-Inducible Gene-I Promotes Apoptosis and Delays Cell Cycle Transition in Cervical Cancer Cells.

    Wang, Jing-Hua; Zhang, Le; Ma, Yu-Wei; Xiao, Jing; Zhang, Yi; Liu, Min; Tang, Hua

    2016-06-01

    The function of retinoic acid-inducible gene-I (RIG-I) in viral replication is well documented, but its function in carcinogenesis and malignancies as well as relationship with microRNAs (miRNAs) remain poorly understood. miR-34a is an antioncogene in multiple tumors. In our study, RIG-I and miR-34a suppressed cell growth, proliferation, migration, and invasion in cervical cancer cells in vitro. miR-34a was validated as a new regulator of RIG-I by binding to its 3' untranslated region and upregulating its expression level. Furthermore, we revealed that RIG-I and miR-34a enhanced apoptosis, delayed the G1/S/G2 transition of the cell cycle, and inhibited the epithelial-mesenchymal transition process to modulate malignancies in cervical cancer cells. Phenotypic rescue experiments indicated that RIG-I mediates the effects of miR-34a in HeLa and C33A cells. These findings provide new insights into the mechanisms that underlie carcinogenesis and may provide new biomarkers for the diagnosis and therapy of cervical cancer. PMID:26910120

  10. Metformin induces apoptosis of pancreatic cancer cells

    2008-01-01

    AIM: To assess the role and mechanism of mefformin in inducing apoptosis of pancreatic cancer cells. METHODS: The human pancreatic cancer cell lines ASPC-1, BxPc-3, PANC-1 and SW1990 were exposed to mefformin. The inhibition of cell proliferation and colony formation via apoptosis induction and S phase arrest in pancreatic cancer cell lines of mefformin was tested.RESULTS: In each pancreatic cancer cell line tested, metformin inhibited cell proliferation in a dose dependent manner in MTS (3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium assays). Flow cytometric analysis showed that metformin reduced the number of cells in G1 and increased the percentage of cells in S phase as well as the apoptotic fraction. Enzymelinked immunosorbent assay (EUSA) showed that metformin induced apaptosis in all pancreatic cancer cell lines. In Western blot studies, metformin induced oly-ADP-ribose polymerase(PARP) cleavage (an indicator of aspase activation) in all pancreatic cancer cell lines. The general caspase inhibitor (VAD-fmk) completely abolished metformin-induced PARP cleavage and apoptosis in ASPC-1 BxPc-3 and PANC-1, the caspase-8 specific inhibitor (IETD-fmk) and the caspase-9 specific inhibitor (LEHD-fmk) only partially abrogated metformin-induced apoptosis and PARP cleavage in BxPc-3 and PANC-1 cells. We also observed that metformin treatment ramatically reduced epidermal growth factor receptor (EGFR) and phosphorylated mitogen activated protein kinase (P-MAPK) in both a time- and dose-dependent manner in all cell lines tested.CONCLUSION: Metformin significantly inhibits cell proliferation and apoptosis in all pancreatic cell lines. And the metformin-induced apoptosis is associated with PARP leavage, activation of caspase-3, -8, and -9 in a time- and dose-dependent manner. Hence, both caspase-8 and -9-initiated apoptotic signaling pathways contribute to metforrnin-induced apoptosis in pancreatic cell lines.

  11. Benzene-Poly-Carboxylic Acid Complex, a Novel Anti-Cancer Agent Induces Apoptosis in Human Breast Cancer Cells

    Fares, Fuad; Azzam, Naiel; Fares, Basem; Larsen, Stig; Lindkaer-Jensen, Steen

    2014-01-01

    Some cases of breast cancer are composed of clones of hormonal-independent growing cells, which do not respond to therapy. In the present study, the effect of Benzene-Poly-Carboxylic Acid Complex (BP-C1) on growth of human breast-cancer cells was tested. BP-C1 is a novel anti-cancer complex of benzene-poly-carboxylic acids with a very low concentration of cis-diammineplatinum (II) dichloride. Human breast cancer cells, MCF-7 and T47D, were used. Cell viability was detected by XTT assay and ap...

  12. Chemotherapy induces tumor clearance independent of apoptosis

    Guerriero, Jennifer L.; Ditsworth, Dara; Fan, Yongjun; Zhao, Fangping; Crawford, Howard C.; Zong, Wei-Xing

    2008-01-01

    Dysregulation of apoptosis is associated with the development of human cancer and resistance to anti-cancer therapy. The ultimate goal of cancer treatment is to selectively induce cancer cell death and overcome drug resistance. A deeper understanding of how a given chemotherapy affects tumor cell death is needed to develop strategically designed anti-cancer agents. Here we utilize a xenograft mouse tumor system generated from genetically defined cells deficient in apoptosis to examine the inv...

  13. Baicalin induced dendritic cell apoptosis in vitro

    HuahuaZhang

    2011-03-01

    Full Text Available This study was aimed to investigate the effects of Baicalin (BA, a major flavonoid constituent found in the herb Baikal skullcap, on dendritic cells (DCs. DCs were generated by culturing murine bone marrow cells for 6 days with granulocyte-macrophage colony-stimulating factor and interleukin-4, and lipopolysaccharide (LPS was added on day 5 to stimulate DCs maturation. The expression levels of DC maturity markers (CD80/CD86 were assessed by flow cytometry using direct immunofluorescence method. Interleukin-12 (IL-12 levels in the culture supernatants were assayed by ELISA. Apoptosis of DCs was analyzed by flow cytometry after Annexin V/propidium iodide staining. The mitochondrial membrane potential changes were measured by using the J-aggregate forming lipophilic cation 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethylbenzimidazolcarbocyanine iodide (JC-1. Exposure of DCs to BA (2-50 microM during bone marrow cell differentiation showed no effects on the up-regulation of CD80/CD86 expression on DCs in response to LPS stimulation, but reduced DCs recovery by inducing apoptosis, and significantly inhibited the release of IL-12 to culture supernatants. BA induced DC apoptosis in a time- and dose-dependent way, and immature DCs were more sensitive for BA-induced apoptosis than mature DC. BA also induced mitochondrial membrane potential changes in DCs. These results demonstrate that BA induces selective apoptosis in immature DCs possibly through mitochondria-mediated pathway.

  14. Excessive reactive oxygen species induces apoptosis in fibroblasts: Role of mitochondrially accumulated hyaluronic acid binding protein 1 (HABP1/p32/gC1qR)

    Constitutively expressed HABP1 in normal murine fibroblast cell line induces growth perturbation, morphological abnormalities alongwith initiation of apoptosis. Here, we demonstrate that though HABP1 accumulation started in mitochondria from 48 hr of growth, induction of apoptosis with the release of cytochrome c and apoptosome complex formation occurred only after 60 hr. This mitochondrial dysfunction was due to gradual increase in ROS generation in HABP1 overexpressing cells. Along with ROS generation, increased Ca2+ influx in mitochondria leading to drop in membrane potential was evident. Interestingly, upon expression of HABP1, the respiratory chain complex I was shown to be significantly inhibited. Electronmicrograph confirmed defective mitochondrial ultrastructure. The reduction in oxidant generation and drop in apoptotic cell population accomplished by disruption of HABP1 expression, corroborating the fact that excess ROS generation in HABP1 overexpressing cells leading to apoptosis was due to mitochondrial HABP1 accumulation

  15. The role of ceramide in receptor- and stress-induced apoptosis studied in acidic ceramidase-deficient Farber disease cells

    Burek, C. J.; Roth, J.; Koch, H. G.; Harzer, K.; Los, Marek Jan; Schulze-Osthoff, Klaus

    2001-01-01

    The activation of sphingomyelinases leading to the generation of ceramide has been implicated in various apoptotic pathways. However, the role of ceramide as an essential death mediator remains highly controversial. In the present study, we investigated the functional relevance of ceramide in a genetic model by using primary cells from a Farber disease patient. These cells accumulate ceramide as the result of an inherited deficiency of acidic ceramidase. We demonstrate that Farber disease lym...

  16. Lipid alterations in human colon epithelial cells induced to differentiation and/or apoptosis by butyrate and polyunsaturated fatty acids

    Hofmanová, Jiřina; Ciganek, M.; Slavík, J.; Kozubík, Alois; Stixová, Lenka; Vaculová, Alena; Dušek, L.; Machala, M.

    2012-01-01

    Roč. 23, č. 6 (2012), s. 539-548. ISSN 0955-2863 R&D Projects: GA ČR(CZ) GA524/07/1178; GA ČR(CZ) GAP301/11/1730 Institutional research plan: CEZ:AV0Z50040507 Institutional support: RVO:68081707 Keywords : Colon cancer * Polyunsaturated fatty acids * Butyrate Subject RIV: BO - Biophysics Impact factor: 4.552, year: 2012

  17. Effects of calcium channel on 3-morpholinosydnonimine-induced rat hippocampal neuronal apoptosis

    Quanzhong Chang; Shuling Zhang; Yuanyin Zheng; Lijuan Xu; Jinbao Yin; Shining Cai

    2011-01-01

    Previous studies have demonstrated that increased chloride channel activity plays a role in nitric oxide-induced neuronal apoptosis in the rat hippocampus.The present study investigated the effects of the broad-spectrum calcium channel blocker CdC12 on survival rate, percentage of apoptosis, and morphological changes in hippocampal neurons cultured in vitro, as well as the effects of calcium channels on neuronal apoptosis.The chloride channel blockers 4-acetamido-4'-isothiocyanatostilbene-2, 2'-disulfonic acid (SITS) or 4, 4'-diisothiocyanostilbene-2,2'-disulfonic acid (DIDS) increased the survival rate of 3-morpholinosydnonimine (SIN-1)-treated neurons and suppressed SIN-1-induced neuronal apoptosis.The calcium channel blocker CdC12 did not increase the survival rate of neurons and did not affect SIN-1-induced apoptosis or SITS- or DIDS-suppressed neuronal apoptosis.Results demonstrated that calcium channels did not significantly affect neuronal apoptosis.

  18. Training-induced apoptosis in skeletal muscle.

    Boffi, F M; Cittar, J; Balskus, G; Muriel, M; Desmaras, E

    2002-09-01

    Apoptosis or programmed cell death is a genetically controlled response of cells to commit suicide and is associated with DNA fragmentation or laddering. The common inducers of apoptosis include Ca2+i and oxygen free radicals/oxidative stress, which are also implicated in the pathogenesis of exercise-induced myopathies. To examine training-induced apoptosis, Thoroughbred horses were subjected to 3 months training programme on a treadmill. At the end of the training programme venous blood samples were taken for a creatine kinase (CK) assay. In addition, muscle biopsy samples were obtained for a membrane lipid peroxidation measurement by malondialdehyde (MDA) assay and for apoptosis detection. Apoptosis was studied by visualising the apoptotic myocytes on the paraffin sections by the modified TUNEL method. DNA laddering was evaluated by subjecting the DNA obtained from the biopsies to 1.5% agarose gel electrophoresis. There was a significant increase (Psupercompensation cycle, when unaccustomed muscle cells activate programmed cell death and are replaced by new and stronger cells, which is the mechanism for training-induced increases in fitness. PMID:12405700

  19. Calpain Activator Dibucaine Induces Platelet Apoptosis

    Jun Liu

    2011-03-01

    Full Text Available Calcium-dependent calpains are a family of cysteine proteases that have been demonstrated to play key roles in both platelet glycoprotein Ibα shedding and platelet activation and altered calpain activity is associated with thrombotic thrombocytopenic purpura. Calpain activators induce apoptosis in several types of nucleated cells. However, it is not clear whether calpain activators induce platelet apoptosis. Here we show that the calpain activator dibucaine induced several platelet apoptotic events including depolarization of the mitochondrial inner transmembrane potential, up-regulation of Bax and Bak, down-regulation of Bcl-2 and Bcl-XL, caspase-3 activation and phosphatidylserine exposure. Platelet apoptosis elicited by dibucaine was not affected by the broad spectrum metalloproteinase inhibitor GM6001. Furthermore, dibucaine did not induce platelet activation as detected by P-selectin expression and PAC-1 binding. However, platelet aggregation induced by ristocetin or α-thrombin, platelet adhesion and spreading on von Willebrand factor were significantly inhibited in platelets treated with dibucaine. Taken together, these data indicate that dibucaine induces platelet apoptosis and platelet dysfunction.

  20. Effect of hyaluronic acid on chondrocyte apoptosis

    Barreto, Ronald Bispo; Sadigursky, David; de Rezende, Marcia Uchoa; Hernandez, Arnaldo José

    2015-01-01

    OBJECTIVE: To determine the percentage of apoptotic cells in a contusion model of osteoarthritis (OA) and to assess whether intra-articular injection of high doses of hyaluronic acid (HA) immediately after trauma reduces chondrocyte apoptosis. METHODS: Forty knees from adult rabbits were impacted thrice with a 1 kg block released through a 1 meter tall cylinder (29.4 Joules). Subsequently, 2 mL of HA was injected in one knee and 2 mL saline in the contra-lateral knee. Medication were administ...

  1. Hydrogen peroxide induces apoptosis via a mitochondrial pathway in chondrocytes

    Zhuang, Cai-ping; Liang, Qian; Wang, Xiao-ping; Chen, Tong-sheng

    2012-03-01

    The degenerative joint disease such as osteoarthritis (OA) is closely associated with the death of chondrocytes in apoptosis fashion. Hydrogen peroxide (H2O2), higher expression following acute damage in OA patients, has been shown to be up-regulated during apoptosis in a bulk of experimental models. This study was aimed to explore the mechanism of H2O2-induced rabbit chondrocytes apoptosis. Articular cartilage was biopsied from the joints of 6 weeks old New Zealand rabbits. Cell Counting Kit (CCK-8) assay was used to assess the inhibitory effect of H2O2 on cell viability. H2O2 treatment induced a remarkable reduction of cell viability. We used flow cytometry to assess the form of cell death with Annexin-V/PI double staining, and found that H2O2 treatment induced apoptosis in a dose-and time-dependent manner. Exposure of chondrocytes to 1.5 mM of H2O2 for 2 h induced a burst apoptosis that can be alleviated by N-acetyl cysteine (NAC) pretreatment, an anti-oxidant amino-acid derivative. Loss of mitochondria membrane potential (▵Ψm) was evaluated using confocal microscopy imaging and flow cytometry (FCM). H2O2 treatment induced a marked reduction of ▵Ψm, and the abrupt disappearance of ▵Ψm occurred within 5 minutes. These results indicate that H2O2 induces a rapid apoptosis via a mitochondrial pathway in rabbit chondrocytes.

  2. Lithium protects ethanol-induced neuronal apoptosis

    Lithium is widely used for the treatment of bipolar disorder. Recent studies have demonstrated its neuroprotective effect. Ethanol is a potent neurotoxin that is particularly harmful to the developing nervous system. In this study, we evaluated lithium's neuroprotection against ethanol-induced apoptosis. Transient exposure of infant mice to ethanol caused apoptotic cell death in brain, which was prevented significantly by administering a low dose of lithium 15 min later. In cultured cerebellar granule neurons, ethanol-induced apoptosis and activation of caspase-3/9, both of which were prevented by lithium. However, lithium's protection is not mediated by its commonly known inhibition of glycogen synthase3β, because neither ethanol nor lithium has significant effects on the phosphorylation of Akt (ser473) or GSK3β (ser9). In addition, the selective GSK-3β inhibitor SB-415286 was unable to prevent ethanol-induced apoptosis. These data suggest lithium may be used as a potential preventive measure for ethanol-induced neurological deficits

  3. Farnesol-induced apoptosis in Candida albicans.

    Shirtliff, Mark E; Krom, Bastiaan P; Meijering, Roelien A M; Peters, Brian M; Zhu, Jingsong; Scheper, Mark A; Harris, Megan L; Jabra-Rizk, Mary Ann

    2009-06-01

    Farnesol, a precursor in the isoprenoid/sterol pathway, was recently identified as a quorum-sensing molecule produced by the fungal pathogen Candida albicans. Farnesol is involved in the inhibition of germination and biofilm formation by C. albicans and can be cytotoxic at certain concentrations. In addition, we have shown that farnesol can trigger apoptosis in mammalian cells via the classical apoptotic pathways. In order to elucidate the mechanism behind farnesol cytotoxicity in C. albicans, the response to farnesol was investigated, using proteomic analysis. Global protein expression profiles demonstrated significant changes in protein expression resulting from farnesol exposure. Among the downregulated proteins were those involved in metabolism, glycolysis, protein synthesis, and mitochondrial electron transport and the respiratory chain, whereas proteins involved in folding, protection against environmental and oxidative stress, actin cytoskeleton reorganization, and apoptosis were upregulated. Cellular changes that accompany apoptosis (regulated cell death) were further analyzed using fluorescent microscopy and gene expression analysis. The results indicated reactive oxygen species accumulation, mitochondrial degradation, and positive terminal deoxynucleotidyltransferase-mediated dUTP-biotin nick end labeling (TUNEL) in the farnesol-exposed cells concurrent with increased expression of antioxidant-encoding and drug response genes. More importantly, the results demonstrated farnesol-induced upregulation of the caspase gene MCA1 and the intracellular presence of activated caspases. In conclusion, this study demonstrated that farnesol promotes apoptosis in C. albicans through caspase activation, implying an important physiological role for farnesol in the fungal cell life cycle with important implications for adaptation and survival. PMID:19364863

  4. Resveratrol induces apoptosis in pancreatic cancer cells

    ZHOU Jia-hua; CHENG Hai-yan; YU Ze-qian; HE Dao-wei; PAN Zheng; YANG De-tong

    2011-01-01

    Background Pancreatic cancer is one of the most lethal human cancers with a very low survival rate of 5 years.Conventional cancer treatments including surgery, radiation, chemotherapy or combinations of these show little effect on this disease. Several proteins have been proved critical to the development and the progression of pancreatic cancer.The aim of this study was to investigate the effect of resveratrol on apoptosis in pancreatic cancer cells.Methods Several pancreatic cancer cell lines were screened by resveratrol, and its toxicity was tested by normal pancreatic cells. Western blotting was then performed to analyze the molecular mechanism of resveratrol induced apoptosis of pancreatic cancer cell lines.Results In the screened pancreatic cancer cell lines, capan-2 and colo357 showed high sensitivity to resveratrol induced apoptosis. Resveratrol exhibited insignificant toxicity to normal pancreatic cells. In resveratrol sensitive cells,capan-2 and colo357, the activation of caspase-3 was detected and showed significant caspase-3 activation upon resveratrol treatment; p53 and p21 were also detected up-regulated upon resveratrol treatment.Conclusion Resveratrol provides a promising anti-tumor stratagy to fight against pancreatic cancer.

  5. Neuroprotective effects of dimerumic acid and deferricoprogen from Monascus purpureus NTU 568-fermented rice against 6-hydroxydopamine-induced oxidative stress and apoptosis in differentiated pheochromocytoma PC-12 cells.

    Tseng, Wei-Ting; Hsu, Ya-Wen; Pan, Tzu-Ming

    2016-08-01

    Context Oxidative stress plays a key role in neurodegenerative disorders, including Parkinson's disease (PD). Rice fermented with Monascus purpureus Went (Monascaceae) NTU 568 (red mould rice) was found to contain antioxidants, including dimerumic acid (DMA) and deferricoprogen (DFC). Objective The effects of DMA and DFC on 6-hydroxydopamine (6-OHDA)-induced cytotoxicity and potential protective mechanisms in differentiated PC-12 pheochromocytoma cells were investigated. Materials and methods DMA (0-60 μM) or DFC (0-10 μM) was co-treated with 6-OHDA (200 μM, 24 h exposure) in differentiated PC-12 cells. Cell viability and intercellular reactive oxygen species (ROS) were measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) and 2',7'-dichlorofluorescein-diacetate (DCFH-DA) assays, respectively. Cell apoptosis was determined by DNA fragmentation analysis and propidium iodide staining by flow cytometry. Western blot analysis was used to measure the levels of cell protein expression. Results DMA and DFC significantly increased cell viability to 72% and 81% in 6-OHDA-induced differentiated PC-12 cell cultures, respectively. Furthermore, DMA and DFC reduced 6-OHDA-induced formation of extracellular and intercellular ROS by 25% and 20%, respectively, and decreased NADPH oxidase-2 expression in differentiated PC-12 cells. DMA and DFC inhibited 6-OHDA-induced apoptosis and decreased activation of caspase-3 via regulation of Bcl-2-associated X protein (Bax) and Bcl-2 protein expression in differentiated PC-12 cells. Conclusion DMA and DFC may protect against 6-OHDA toxicity by inhibiting ROS formation and apoptosis. These results showed that the metabolites from M. purpureus NTU 568 fermentation were potential therapeutic agents for PD induced by oxidative damage and should be encouraged for further research. PMID:26794209

  6. Curcumin and Ellagic acid synergistically induce ROS generation, DNA damage, p53 accumulation and apoptosis in HeLa cervical carcinoma cells.

    Kumar, Devbrat; Basu, Soumya; Parija, Lucy; Rout, Deeptimayee; Manna, Sanjeet; Dandapat, Jagneshwar; Debata, Priya Ranjan

    2016-07-01

    Cervical cancer and precancerous lesions of the cervix continue to be a global health issue, and the medication for the treatment for chronic HPV infection so far has not been effective. Potential anticancer and anti HPV activities of two known phytochemicals, Curcumin and Ellagic acid were evaluated in HeLa cervical cancer cells. Curcumin is a natural compound found in the root of Curcuma longa plant and Ellagic acid a polyphenol found in fruits of strawberries, raspberries and walnuts. The combination of Curcumin and Ellagic acid at various concentrations showed better anticancer properties than either of the drug when used alone as evidenced by MTT assay. Besides this, Curcumin and Ellagic acid also restore p53, induce ROS formation and DNA damage. Mechanistic study further indicated that Curcumin and Ellagic acid show anti-HPV activity as evidenced by decrease in the HPV E6 oncoprotein on HeLa cells. PMID:27261574

  7. Emodin induces embryonic toxicity in mouse blastocysts through apoptosis

    Emodin (1,3,8-trihydroxy-6-methylanthraquinone), a major constituent of rhubarb, has a wide range of therapeutic applications. Previous studies have established that emodin inhibits cell proliferation and induces caspase 3-dependent apoptosis. However, its side-effects, particularly those on embryonic development, have not been well characterized as yet. In the current study, we examined the cytotoxic effects of emodin on mouse embryos at the blastocyst stage, subsequent embryonic attachment and outgrowth in vitro, and in vivo implantation by embryo transfer. Blastocysts treated with 25–75 μM emodin exhibited significantly increased apoptosis and a corresponding decrease in total cell number. Notably, the implantation success rate of blastocysts pretreated with emodin was lower than that of their control counterparts. Moreover, in vitro treatment with 25–75 μM emodin was associated with increased resorption of post-implantation embryos and decreased fetal weight. With the aid of an in vivo mouse model, we showed that consumption of drinking water containing emodin led to apoptosis and decreased cell proliferation, and inhibited early embryonic development to the blastocyst stage. Our findings support a degree of selective inhibition of retinoic acid receptors in blastocysts treated with emodin. In addition, emodin appears to induce injury in mouse blastocysts through intrinsic apoptotic signaling processes to impair sequent embryonic development. These results collectively indicate that emodin has the potential to induce embryonic cytotoxicity.

  8. Blockage of miR-92a-3p with locked nucleic acid induces apoptosis and prevents cell proliferation in human acute megakaryoblastic leukemia.

    Sharifi, M; Salehi, R

    2016-01-01

    MicroRNAs (miRNAs) are non-coding RNAs involved in post-transcriptional regulation of gene expression. In many cancers, up- or downregulation of different miRNAs is reported. In acute myeloid leukemia, upregulation of miR-92a-3p was reported in human in vitro studies. We performed blockage of miR-29a-3p in human acute megakaryoblastic leukemia cell line (M-07e) by using locked nucleic acid (LNA) and cell proliferation; apoptosis and necrosis were assessed. At different time points after LNA-anti-miR92a-3p transfection, miR-92a-3p quantitation was assessed by qRT-real-time PCR, MTT assay and annexin/propidium iodide staining were performed. The data were processed using the ANOVA test. At all three time points, the expression of miR-92a-3p was lower in the LNA-anti-miR group compared with the control groups. Cell viability between LNA-Anti-miR and the control group was statistically significant. Blockage of miR-92a-3p was associated with increment of the ratio of apoptotic cells in the LNA-anti-miR group was higher than the other group. The ratio of necrotic cells in the LNA-antimiR group was higher than the other groups. These assessments indicate that miR-92a-3p blockage can decrease the viability of M-07e cells, which is mainly due to induction of apoptosis and necrosis. Our findings could open up a path to a miRNA based therapeutic approach for treatment of acute megakaryoblastic leukemia. PMID:26658357

  9. Molecular mechanisms of TRAIL-induced apoptosis of cancer cells

    2001-01-01

    @@Tumor Necrosis Factor-related Apoptosis-inducing Ligand (TRAIL) is a recently identified member of the tumor necrosis factor (TNF) family[1]. Numerous studies indicate that TRAIL can induce apoptosis of cancer cells but not of normal cells, pointing to the possibility of de-veloping TRAIL into a cancer drug[2-4]. This review will summary the molecular mechanisms of TRAIL-induced apoptosis and discuss the questions to be resolved in this field.

  10. Activation of PPARδ up-regulates fatty acid oxidation and energy uncoupling genes of mitochondria and reduces palmitate-induced apoptosis in pancreatic β-cells

    Recent evidence indicates that decreased oxidative capacity, lipotoxicity, and mitochondrial aberrations contribute to the development of insulin resistance and type 2 diabetes. The goal of this study was to investigate the effects of peroxisome proliferator-activated receptor δ (PPARδ) activation on lipid oxidation, mitochondrial function, and insulin secretion in pancreatic β-cells. After HIT-T15 cells (a β-cell line) were exposed to high concentrations of palmitate and GW501516 (GW; a selective agonist of PPARδ), we found that administration of GW increased the expression of PPARδ mRNA. GW-induced activation of PPARδ up-regulated carnitine palmitoyltransferase 1 (CPT1), long-chain acyl-CoA dehydrogenase (LCAD), pyruvate dehydrogenase kinase 4 (PDK4), and uncoupling protein 2 (UCP2); alleviated mitochondrial swelling; attenuated apoptosis; and reduced basal insulin secretion induced by increased palmitate in HIT cells. These results suggest that activation of PPARδ plays an important role in protecting pancreatic β-cells against aberrations caused by lipotoxicity in metabolic syndrome and diabetes.

  11. Activation of PPAR{delta} up-regulates fatty acid oxidation and energy uncoupling genes of mitochondria and reduces palmitate-induced apoptosis in pancreatic {beta}-cells

    Wan, Jun; Jiang, Li; Lue, Qingguo; Ke, Linqiu [Department of Endocrinology, West China Hospital of Sichuan University, 37 Guoxue Lane, Chengdu, Sichuan 610041 (China); Li, Xiaoyu [State Key Laboratory of Oral Diseases, Sichuan University, No. 14, 3rd Section, Renmin South Road, Chengdu, Sichuan 610041 (China); Tong, Nanwei, E-mail: buddyjun@hotmail.com [Department of Endocrinology, West China Hospital of Sichuan University, 37 Guoxue Lane, Chengdu, Sichuan 610041 (China)

    2010-01-15

    Recent evidence indicates that decreased oxidative capacity, lipotoxicity, and mitochondrial aberrations contribute to the development of insulin resistance and type 2 diabetes. The goal of this study was to investigate the effects of peroxisome proliferator-activated receptor {delta} (PPAR{delta}) activation on lipid oxidation, mitochondrial function, and insulin secretion in pancreatic {beta}-cells. After HIT-T15 cells (a {beta}-cell line) were exposed to high concentrations of palmitate and GW501516 (GW; a selective agonist of PPAR{delta}), we found that administration of GW increased the expression of PPAR{delta} mRNA. GW-induced activation of PPAR{delta} up-regulated carnitine palmitoyltransferase 1 (CPT1), long-chain acyl-CoA dehydrogenase (LCAD), pyruvate dehydrogenase kinase 4 (PDK4), and uncoupling protein 2 (UCP2); alleviated mitochondrial swelling; attenuated apoptosis; and reduced basal insulin secretion induced by increased palmitate in HIT cells. These results suggest that activation of PPAR{delta} plays an important role in protecting pancreatic {beta}-cells against aberrations caused by lipotoxicity in metabolic syndrome and diabetes.

  12. All-trans retinoic acid inhibits KIT activity and induces apoptosis in gastrointestinal stromal tumor GIST-T1 cell line by affecting on the expression of survivin and Bax protein

    Taguchi Takahiro

    2010-12-01

    Full Text Available Abstract Background Imatinib, a selective tyrosine kinase inhibitor, has been used as a standard first-line therapy for irresectable and metastasized gastrointestinal stromal tumor (GIST patients. Unfortunately, most patients responding to imatinib will eventually exhibit imatinib-resistance, the cause of which is not fully understood. The serious clinical problem of imatinib-resistance demands alternative therapeutic strategy. This study was conducted to investigate the effect of all-trans retinoic acid (ATRA on GIST cell lines. Methods Cell proliferation was determined by trypan blue dye exclusion test. Western blot analysis was performed to test the expression of activated KIT, its downstream proteins, and apoptosis associated proteins. The cytotoxic interactions of imatinib with ATRA were evaluated using the isobologram of Steel and Peckham. Results and conclusion In this work, for the first time we have demonstrated that ATRA affected on cell proliferation of GIST-T1 and GIST-882 cell line through inhibition of cell growth in a dose dependent manner and induced apoptosis. High dose of ATRA induced morphologic change in GIST-T1 cells, rounded-up cells, and activated the caspase-3 protein. In further examination, we found that the ATRA-induced apoptosis in GIST-T1 cells was accompanied by the down-regulated expression of survivin and up-regulated expression of Bax protein. Moreover, ATRA suppressed the activity of KIT protein in GIST-T1 cells and its downstream signal, AKT activity, but not MAPK activity. We also have demonstrated that combination of ATRA with imatinib showed additive effect by isobologram, suggesting that the combination of ATRA and imatinib may be a novel potential therapeutic option for GIST treatment. Furthermore, the scracht assay result suggested that ATRA was a potential reagent to prevent the invasion or metastasis of GIST cells.

  13. D-saccharic acid-1,4-lactone ameliorates alloxan-induced diabetes mellitus and oxidative stress in rats through inhibiting pancreatic beta-cells from apoptosis via mitochondrial dependent pathway

    Oxidative stress plays a vital role in diabetic complications. To suppress the oxidative stress mediated damage in diabetic pathophysiology, a special focus has been given on naturally occurring antioxidants present in normal diet. D-saccharic acid 1,4-lactone (DSL), a derivative of D-glucaric acid, is present in many dietary plants and is known for its detoxifying and antioxidant properties. The aim of the present study was to evaluate the beneficial role of DSL against alloxan (ALX) induced diabetes in the pancreas tissue of Swiss albino rats. A dose-dependent study for DSL (20–120 mg/kg body weight) was carried out to find the effective dose of the compound in ALX-induced diabetic rats. ALX exposure elevated the blood glucose, glycosylated Hb, decreased the plasma insulin and disturbed the intra-cellular antioxidant machineries whereas oral administration of DSL at a dose of 80 mg/kg body weight restored these alterations close to normal. Investigating the mechanism of the protective activity of DSL we observed that it prevented the pancreatic β-cell apoptosis via mitochondria-dependent pathway. Results showed decreased mitochondrial membrane potential, enhanced cytochrome c release in the cytosol and reciprocal regulation of Bcl-2 family proteins in the diabetic rats. These events were also found to be associated with increased level of Apaf-1, caspase 9, and caspase 3 that ultimately led to pancreatic β-cell apoptosis. DSL treatment, however, counteracted these changes. In conclusion, DSL possesses the capability of ameliorating the oxidative stress in ALX-induced diabetes and thus could be a promising approach in lessening diabetic complications. Highlights: ► Oxidative stress is suggested as a key event in the pathogenesis of diabetes. ► D-saccharic acid 1,4-lactone (DSL) reduces the alloxan-induced diabetes mellitus. ► DSL normalizes cellular antioxidant machineries disturbed due to alloxan toxicity. ► DSL inhibits pancreatic β-cells apoptosis

  14. D-saccharic acid-1,4-lactone ameliorates alloxan-induced diabetes mellitus and oxidative stress in rats through inhibiting pancreatic beta-cells from apoptosis via mitochondrial dependent pathway

    Bhattacharya, Semantee [Department of Life Sciences and Biotechnology, Jadavpur University, 188, Raja S C Mullick Road, Kolkata 700 032 (India); Manna, Prasenjit [Division of Molecular Medicine, Bose Institute, P-1/12, CIT Scheme VII M, Kolkata-700054 (India); Gachhui, Ratan [Department of Life Sciences and Biotechnology, Jadavpur University, 188, Raja S C Mullick Road, Kolkata 700 032 (India); Sil, Parames C., E-mail: parames@bosemain.boseinst.ac.in [Division of Molecular Medicine, Bose Institute, P-1/12, CIT Scheme VII M, Kolkata-700054 (India)

    2011-12-15

    Oxidative stress plays a vital role in diabetic complications. To suppress the oxidative stress mediated damage in diabetic pathophysiology, a special focus has been given on naturally occurring antioxidants present in normal diet. D-saccharic acid 1,4-lactone (DSL), a derivative of D-glucaric acid, is present in many dietary plants and is known for its detoxifying and antioxidant properties. The aim of the present study was to evaluate the beneficial role of DSL against alloxan (ALX) induced diabetes in the pancreas tissue of Swiss albino rats. A dose-dependent study for DSL (20-120 mg/kg body weight) was carried out to find the effective dose of the compound in ALX-induced diabetic rats. ALX exposure elevated the blood glucose, glycosylated Hb, decreased the plasma insulin and disturbed the intra-cellular antioxidant machineries whereas oral administration of DSL at a dose of 80 mg/kg body weight restored these alterations close to normal. Investigating the mechanism of the protective activity of DSL we observed that it prevented the pancreatic {beta}-cell apoptosis via mitochondria-dependent pathway. Results showed decreased mitochondrial membrane potential, enhanced cytochrome c release in the cytosol and reciprocal regulation of Bcl-2 family proteins in the diabetic rats. These events were also found to be associated with increased level of Apaf-1, caspase 9, and caspase 3 that ultimately led to pancreatic {beta}-cell apoptosis. DSL treatment, however, counteracted these changes. In conclusion, DSL possesses the capability of ameliorating the oxidative stress in ALX-induced diabetes and thus could be a promising approach in lessening diabetic complications. Highlights: Black-Right-Pointing-Pointer Oxidative stress is suggested as a key event in the pathogenesis of diabetes. Black-Right-Pointing-Pointer D-saccharic acid 1,4-lactone (DSL) reduces the alloxan-induced diabetes mellitus. Black-Right-Pointing-Pointer DSL normalizes cellular antioxidant machineries

  15. Oxidative stress in NSC-741909-induced apoptosis of cancer cells

    Huang Peng

    2010-04-01

    Full Text Available Abstract Background NSC-741909 is a novel anticancer agent that can effectively suppress the growth of several cell lines derived from lung, colon, breast, ovarian, and kidney cancers. We recently showed that NSC-741909-induced antitumor activity is associated with sustained Jun N-terminal kinase (JNK activation, resulting from suppression of JNK dephosphorylation associated with decreased protein levels of MAPK phosphatase-1. However, the mechanisms of NSC-741909-induced antitumor activity remain unclear. Because JNK is frequently activated by oxidative stress in cells, we hypothesized that reactive oxygen species (ROS may be involved in the suppression of JNK dephosphorylation and the cytotoxicity of NSC-741909. Methods The generation of ROS was measured by using the cell-permeable nonfluorescent compound H2DCF-DA and flow cytometry analysis. Cell viability was determined by sulforhodamine B assay. Western blot analysis, immunofluorescent staining and flow cytometry assays were used to determine apoptosis and molecular changes induced by NSC-741909. Results Treatment with NSC-741909 induced robust ROS generation and marked MAPK phosphatase-1 and -7 clustering in NSC-741909-sensitive, but not resistant cell lines, in a dose- and time-dependent manner. The generation of ROS was detectable as early as 30 min and ROS levels were as high as 6- to 8-fold above basal levels after treatment. Moreover, the NSC-741909-induced ROS generation could be blocked by pretreatment with antioxidants, such as nordihydroguaiaretic acid, aesculetin, baicalein, and caffeic acid, which in turn, inhibited the NSC-741909-induced JNK activation and apoptosis. Conclusion Our results demonstrate that the increased ROS production was associated with NSC-741909-induced antitumor activity and that ROS generation and subsequent JNK activation is one of the primary mechanisms of NSC-741909-mediated antitumor cell activity.

  16. Paclitaxel induces apoptosis in human gastric carcinoma cells

    Hai-Bo Zhou; Ju-Ren Zhu

    2003-01-01

    AIM: To investigate the apoptosis in gastric cancer cells induced by paclitaxel, and the relation between this apoptosis and expression of Bcl-2 and Bax.METHODS: In in vitro experiments, MTT assay was used to determine the cell growth inhibitory rate. Transmission electron microscope and TUNEL staining method were used to quantitatively and qualitively detect the apoptosis status of gastric cancer cell line SGC-7901 before and after the paditaxel treatment. Immunohistochemical staining was used to detect the expression of apoptosis-regulated gene Bcl-2and Bax.RESULTS: Paclitaxel inhibited the growth of gastric cancer cell line SGC-7901 in a dose-and time-dependent manner.Paclitaxel induced SGC-7901 cells to undergo apoptosis with typically apoptotic characteristics, including morphological changes of chromatin condensation, chromatin crescent formation, nucleus fragmentation and apoptotic body formation. Paclitaxel could reduce the expression of apoptosis-regulated gene Bcl-2, and improve the expression of apoptosis-regulated gene Bax.CONCLUSION: Paclitaxel is able to induce the apoptosis in gastric cancer. This apoptosis may be mediated by downexpression of apoptosis-regulated gene Bcl-2 and upexpression of apoptosis-regulated gene Bax.

  17. α-Linolenic acid prevents endoplasmic reticulum stress-mediated apoptosis of stearic acid lipotoxicity on primary rat hepatocytes

    Shi Hongyang

    2011-05-01

    Full Text Available Abstract Aims Lipid accumulation in non-adipose tissues leads to cell dysfunction and apoptosis, a phenomenon known as lipotoxicity. Unsaturated fatty acids may offset the lipotoxicity associated with saturated fatty acids. Stearic acid induced endoplasmic reticulum (ER stress and caused apoptotic and necrotic cell death in the primary rat hepatocytes. Methods Cell viability was investigated using MTT assay, and apoptosis was evaluated with Hoechst 33342 staining. Western blot analysis was used to examine the changes in the expression levels of glucose regulated protein 78 (GRP78, glucose regulated protein 94 (GRP94, and C/EBP homologous protein (CHOP. Caspase-3 activity was evaluated using a Caspase-3 substrate kit. Results We have studied the ability of α-linolenic acid to prevent endoplasmic reticulum stress-mediated apoptosis of rat hepatocytes elicited by stearic acid and thapsigargin. Incubation of primary rat hepatocytes for 16 h with stearic acid produced a significant increase in cell death. Stearic acid also increased levels of three indicators of ER stress -- GRP78, CHOP, and GRP94. α-Linolenic acid distinctly reduced cell death and levels of all three indicators of ER stress brought about by stearic acid. Thapsigargin, which induces ER stress produced similar effects to those obtained using stearic acid; its effects were partly reversed by α-linolenic acid. Conclusion These results suggest that α-linolenic acid prevents ER stress-mediated apoptosis of stearic acid lipotoxicity on primary rat hepatocytes might become a target to develop new antiapoptotic compounds in nonalcoholic fatty liver disease (NAFLD.

  18. Carbamate Pesticide-Induced Apoptosis in Human T Lymphocytes

    Qing Li

    2015-04-01

    Full Text Available We previously found that carbamate pesticides induced significant apoptosis in human natural killer cells. To investigate whether carbamate pesticides also induce apoptosis in human T lymphocytes, in the present study Jurkat human T cells were treated in vitro with thiram, maneb, carbaryl or ziram. Apoptosis was determined by FITC-Annexin-V/PI staining. To explore the mechanism of apoptosis, intracellular levels of active caspase 3 and mitochondrial cytochrome-c release were determined by flow cytometry. We found that thiram, ziram, maneb and carbaryl also induced apoptosis in a time- and dose-dependent manner in the human T cells. However, the strength of the apoptosis-inducing effect differed among the pesticides, with the: thiram > ziram > maneb > carbaryl. Moreover, thiram significantly increased the intracellular level of active caspase 3 and caspase inhibitors significantly inhibited apoptosis. Thiram also significantly caused mitochondrial cytochrome-c release. These findings indicate that carbamate pesticides can induce apoptosis in human T cells, and the apoptosis is mediated by the activation of caspases and the release of mitochondrial cytochrome-c.

  19. Clitocybe alexandri extract induces cell cycle arrest and apoptosis in a lung cancer cell line: identification of phenolic acids with cytotoxic potential

    Vaz, Josiana A.; Almeida, Gabriela M.; Ferreira, Isabel C.F.R.; Martins, Anabela; Vasconcelos, M. Helena

    2012-01-01

    Mushrooms are a possible rich source of biologically active compounds with potential for drug discovery. The aim of this work was to gain further insight into the citotoxicity mechanism of action of Clitocybe alexandri ethanolic extract against a lung cancer cell line (NCI-H460 cells). The effects on cell cycle profile and levels of apoptosis were evaluated by flow cytometry, and the effect on the expression levels of proteins related to cellular apoptosis was also investigated by Western blo...

  20. ING1 induces apoptosis through direct effects at the mitochondria

    Bose, P; Thakur, S; Thalappilly, S;

    2013-01-01

    translocates to the mitochondria of primary fibroblasts and established epithelial cell lines in response to apoptosis inducing stimuli, independent of the cellular p53 status. The ability of ING1 to induce apoptosis in various breast cancer cell lines correlates well with its degree of translocation to the...... mitochondria after UV treatment. Endogenous ING1 protein specifically interacts with the pro-apoptotic BCL2 family member BAX, and colocalizes with BAX in a UV-inducible manner. Ectopic expression of a mitochondria-targeted ING1 construct is more proficient in inducing apoptosis than the wild type ING1 protein...

  1. Protective Effect of Caffeic Acid on Paclitaxel Induced Anti-Proliferation and Apoptosis of Lung Cancer Cells Involves NF-κB Pathway

    Yao Fong

    2012-05-01

    Full Text Available Caffeic acid (CA, a natural phenolic compound, is abundant in medicinal plants. CA possesses multiple biological effects such as anti-bacterial and anti-cancer growth. CA was also reported to induce fore stomach and kidney tumors in a mouse model. Here we used two human lung cancer cell lines, A549 and H1299, to clarify the role of CA in cancer cell proliferation. The growth assay showed that CA moderately promoted the proliferation of the lung cancer cells. Furthermore, pre-treatment of CA rescues the proliferation inhibition induced by a sub-IC50 dose of paclitaxel (PTX, an anticancer drug. Western blot showed that CA up-regulated the pro-survival proteins survivin and Bcl-2, the down-stream targets of NF-κB. This is consistent with the observation that CA induced nuclear translocation of NF-κB p65. Our study suggested that the pro-survival effect of CA on PTX-treated lung cancer cells is mediated through a NF-κB signaling pathway. This may provide mechanistic insights into the chemoresistance of cancer calls.

  2. Preprogrammed and programmed cell death mechanisms of apoptosis: UV-induced immediate and delayed apoptosis

    Equitoxic doses (10% clonogenic survival) of UV radiation (UVR) from the three waveband regions, i.e. UVA1 (340-400 nm), UVB (290-320 nm) and UVC (200-290 nm), were shown to induce immediate or delayed apoptosis in L5178Y-R murine lymphoma cells. Membrane and DNA damage were shown to be the most probable initiators of UVA1-induced immediate or UVR-induced delayed apoptosis, respectively. These UV-induced apoptotic processes appeared to utilize two different ''core'' biochemical mechanisms; however, one core mechanism could be initiated at two distinct sites (e.g. membrane or DNA) and result in disparate kinetics. In an attempt to resolve this mechanistic issue, the dependence on macromolecular synthesis of each UV-induced apoptotic mechanism was investigated. In the absence of UVR, inhibition of either transcription (actinomycin D) or translation (cycloheximide) induced apoptosis in a concentration-and time-dependent manner. These results suggest that an apoptotic mechanism exists that does not require macromolecular synthesis postinsult (constitutive). The UVR data demonstrate that UVA-1 induced immediate apoptosis utilizes this constitutive mechanism (preprogrammed), while UVR-induced delayed apoptosis utilizes the well-known inducible mechanism (programmed). Therefore, there are two different core biochemical mechanisms of apoptotic death available to each cell: preprogrammed (constitutive) and programmed (inducible) cell death. (Author)

  3. Docosahexaenoic Acid Modulates a HER2-Associated Lipogenic Phenotype, Induces Apoptosis, and Increases Trastuzumab Action in HER2-Overexpressing Breast Carcinoma Cells

    Graziela Rosa Ravacci

    2015-01-01

    Full Text Available In breast cancer, lipid metabolic alterations have been recognized as potential oncogenic stimuli that may promote malignancy. To investigate whether the oncogenic nature of lipogenesis closely depends on the overexpression of HER2 protooncogene, the normal breast cell line, HB4a, was transfected with HER2 cDNA to obtain HER2-overexpressing HB4aC5.2 cells. Both cell lines were treated with trastuzumab and docosahexaenoic acid. HER2 overexpression was accompanied by an increase in the expression of lipogenic genes involved in uptake (CD36, transport (FABP4, and storage (DGAT of exogenous fatty acids (FA, as well as increased activation of “de novo” FA synthesis (FASN. We further investigate whether this lipogenesis reprogramming might be regulated by mTOR/PPARγ pathway. Inhibition of the mTORC1 pathway markers, p70S6 K1, SREBP1, and LIPIN1, as well as an increase in DEPTOR expression (the main inhibitor of the mTOR was detected in HB4aC5.2. Based on these results, a PPARγ selective antagonist, GW9662, was used to treat both cells lines, and the lipogenic genes remained overexpressed in the HB4aC5.2 but not HB4a cells. DHA treatment inhibited all lipogenic genes (except for FABP4 in both cell lines yet only induced death in the HB4aC5.2 cells, mainly when associated with trastuzumab. Neither trastuzumab nor GW9662 alone was able to induce cell death. In conclusion, oncogenic transformation of breast cells by HER2 overexpression may require a reprogramming of lipogenic genetic that is independent of mTORC1 pathway and PPARγ activity. This reprogramming was inhibited by DHA.

  4. Hyaluronic acid-fabricated nanogold delivery of the inhibitor of apoptosis protein-2 siRNAs inhibits benzo[a]pyrene-induced oncogenic properties of lung cancer A549 cells

    Lin, Chung-Ming; Kao, Wei-Chien; Yeh, Chun-An; Chen, Hui-Jye; Lin, Shinn-Zong; Hsieh, Hsien-Hsu; Sun, Wei-Shen; Chang, Chih-Hsuan; Hung, Huey-Shan

    2015-03-01

    Benzo[a]pyrene (BaP), a component of cooking oil fumes (COF), promotes lung cancer cell proliferation and survival via the induction of inhibitor of apoptosis protein-2 (IAP-2) proteins. Thus knockdown of IAP-2 would be a promising way to battle against lung cancer caused by COF. Functionalized gold nanoparticle (AuNP) is an effective delivery system for bio-active materials. Here, biocompatible hyaluronic acid (HA) was fabricated into nanoparticles to increase the target specificity by binding to CD44-over-expressed cancer cells. IAP-2-specific small-interfering RNA (siRNAs) or fluorescein isothiocyanate (FITC) were then incorporated into AuNP-HA. Conjugation of IAP-2 siRNA into AuNPs-HA was verified by the UV-vis spectrometer and Fourier transform infrared spectrometer. Further studies showed that AuNP-HA/FITC were effectively taken up by A549 cells through CD44-mediated endocytosis. Incubation of BaP-challenged cells with AuNP-HA-IAP-2 siRNAs silenced the expression of IAP-2, decreased cell proliferation and triggered pronounced cell apoptosis by the decrease in Bcl-2 protein and the increase in Bax protein as well as the active form of caspases-3. The BaP-elicited cell migration and enzymatic activity of the secreted matrix metalloproteinase-2 were also substantially suppressed by treatment with AuNP-HA-IAP-2 siRNAs. These results indicated that IAP-2 siRNAs can be efficiently delivered into A549 cells by functionalized AuNP-HA to repress the IAP-2 expression and BaP-induced oncogenic events, suggesting the potential therapeutic application of IAP-2 siRNA or other siRNA-conjugated AuNP-HA composites to COF-induced lung cancer and other gene-caused diseases in the future.

  5. Overexpressed TP73 induces apoptosis in medulloblastoma

    Perlaky Laszlo

    2007-07-01

    Full Text Available Abstract Background Medulloblastoma is the most common malignant brain tumor of childhood. Children who relapse usually die of their disease, which reflects resistance to radiation and/or chemotherapy. Improvements in outcome require a better understanding of the molecular basis of medulloblastoma growth and treatment response. TP73 is a member of the TP53 tumor suppressor gene family that has been found to be overexpressed in a variety of tumors and mediates apoptotic responses to genotoxic stress. In this study, we assessed expression of TP73 RNA species in patient tumor specimens and in medulloblastoma cell lines, and manipulated expression of full-length TAp73 and amino-terminal truncated ΔNp73 to assess their effects on growth. Methods We analyzed medulloblastoma samples from thirty-four pediatric patients and the established medulloblastoma cell lines, Daoy and D283MED, for expression of TP73 RNA including the full-length transcript and the 5'-terminal variants that encode the ΔNp73 isoform, as well as TP53 RNA using quantitative real time-RTPCR. Protein expression of TAp73 and ΔNp73 was quantitated with immunoblotting methods. Clinical outcome was analyzed based on TP73 RNA and p53 protein expression. To determine effects of overexpression or knock-down of TAp73 and ΔNp73 on cell cycle and apoptosis, we analyzed transiently transfected medulloblastoma cell lines with flow cytometric and TUNEL methods. Results Patient medulloblastoma samples and cell lines expressed full-length and 5'-terminal variant TP73 RNA species in 100-fold excess compared to non-neoplastic brain controls. Western immunoblot analysis confirmed their elevated levels of TAp73 and amino-terminal truncated ΔNp73 proteins. Kaplan-Meier analysis revealed trends toward favorable overall and progression-free survival of patients whose tumors display TAp73 RNA overexpression. Overexpression of TAp73 or ΔNp73 induced apoptosis under basal growth conditions in vitro and

  6. Wogonoside induces autophagy-related apoptosis in human glioblastoma cells.

    Zhang, Li; Wang, Handong; Cong, Zixiang; Xu, Jianguo; Zhu, Jianhong; Ji, Xiangjun; Ding, Ke

    2014-09-01

    Wogonoside, a bioactive flavonoid extracted from the root of Scutellaria baicalensis Georgi, has shown preclinical anticancer efficacy in various cancer models. However, the effects of wogonoside on glioblastoma cells remain unclear. In the present study, we found that wogonoside exhibited a cytotoxic effect on human glioblastoma cells. The suppression of cell viability was due to the induction of mitochondrial apoptosis. Furthermore, the presence of autophagic hallmarks, including an increase in punctate microtubule associated protein 1 light chain 3 (LC3) dots, changes in cellular morphology and increased levels of autophagy-related proteins were observed in the wogonoside-treated cells. Wogonoside treatment also enhanced autophagic flux as reflected by the increased acidic vesicular organelle (AVO) formation, p62 degradation and LC3 turnover. Notably, blockade of autophagy by a chemical inhibitor or RNA interference decreased the anticancer effect of wogonoside. In addition, the p38 mitogen-activated protein kinase (MAPK) signaling pathway, the phosphatidylinositide 3-kinase/protein kinase B/mammalian target of rapamycin/p70S6 kinase (PI3K/AKT/mTOR/p70S6K) signaling pathway and reactive oxygen species (ROS) participated in wogonoside-induced autophagy and apoptosis. These findings support the initiation of further studies of wogonoside as a candidate for the treatment of human malignant glioma. PMID:24970553

  7. The interplays between autophagy and apoptosis induced by enterovirus 71.

    Xueyan Xi

    Full Text Available BACKGROUND: Enterovirus 71 (EV71 is the causative agent of human diseases with distinct severity, from mild hand, foot and mouth disease to severe neurological syndromes, such as encephalitis and meningitis. The lack of understanding of viral pathogenesis as well as lack of efficient vaccine and drugs against this virus impedes the control of EV71 infection. EV71 virus induces autophagy and apoptosis; however, the relationship between EV71-induced autophagy and apoptosis as well as the influence of autophagy and apoptosis on virus virulence remains unclear. METHODOLOGY/PRINCIPAL FINDINGS: In this study, it was observed that the Anhui strain of EV71 induced autophagy and apoptosis in human rhabdomyosarcoma (RD-A cells. Additionally, by either applying chemical inhibitors or knocking down single essential autophagic or apoptotic genes, inhibition of EV71 induced autophagy inhibited the apoptosis both at the autophagosome formation stage and autophagy execution stage. However, inhibition of autophagy at the stage of autophagosome and lysosome fusion promoted apoptosis. In reverse, the inhibition of EV71-induced apoptosis contributed to the conversion of microtubule-associated protein 1 light chain 3-I (LC3-I to LC3-II and degradation of sequestosome 1 (SQSTM1/P62. Furthermore, the inhibition of autophagy in the autophagsome formation stage or apoptosis decreased the release of EV71 viral particles. CONCLUSIONS/SIGNIFICANCE: In conclusion, the results of this study not only revealed novel aspect of the interplay between autophagy and apoptosis in EV71 infection, but also provided a new insight to control EV71 infection.

  8. Apoptosis signal-regulating kinase 1 mediates denbinobin-induced apoptosis in human lung adenocarcinoma cells

    Pan Shiow-Lin

    2009-05-01

    Full Text Available Abstract In the present study, we explore the role of apoptosis signal-regulating kinase 1 (ASK1 in denbinobin-induced apoptosis in human lung adenocarcinoma (A549 cells. Denbinobin-induced cell apoptosis was attenuated by an ASK1 dominant-negative mutant (ASK1DN, two antioxidants (N-acetyl-L-cysteine (NAC and glutathione (GSH, a c-Jun N-terminal kinase (JNK inhibitor (SP600125, and an activator protein-1 (AP-1 inhibitor (curcumin. Treatment of A549 cells with denbinobin caused increases in ASK1 activity and reactive oxygen species (ROS production, and these effects were inhibited by NAC and GSH. Stimulation of A549 cells with denbinobin caused JNK activation; this effect was markedly inhibited by NAC, GSH, and ASK1DN. Denbinobin induced c-Jun phosphorylation, the formation of an AP-1-specific DNA-protein complex, and Bim expression. Bim knockdown using a bim short interfering RNA strategy also reduced denbinobin-induced A549 cell apoptosis. The denbinobin-mediated increases in c-Jun phosphorylation and Bim expression were inhibited by NAC, GSH, SP600125, ASK1DN, JNK1DN, and JNK2DN. These results suggest that denbinobin might activate ASK1 through ROS production to cause JNK/AP-1 activation, which in turn induces Bim expression, and ultimately results in A549 cell apoptosis.

  9. Glucocorticoid Induced Leucine Zipper inhibits apoptosis of cardiomyocytes by doxorubicin

    Aguilar, David; Strom, Joshua; Chen, Qin M., E-mail: qchen@email.arizona.edu

    2014-04-01

    Doxorubicin (Dox) is an indispensable chemotherapeutic agent for the treatment of various forms of neoplasia such as lung, breast, ovarian, and bladder cancers. Cardiotoxicity is a major concern for patients receiving Dox therapy. Previous work from our laboratory indicated that glucocorticoids (GCs) alleviate Dox-induced apoptosis in cardiomyocytes. Here we have found Glucocorticoid-Induced Leucine Zipper (GILZ) to be a mediator of GC-induced cytoprotection. GILZ was found to be induced in cardiomyocytes by GC treatment. Knocking down of GILZ using siRNA resulted in cancelation of GC-induced cytoprotection against apoptosis by Dox treatment. Overexpressing GILZ by transfection was able to protect cells from apoptosis induced by Dox as measured by caspase activation, Annexin V binding and morphologic changes. Western blot analyses indicate that GILZ overexpression prevented cytochrome c release from mitochondria and cleavage of caspase-3. When bcl-2 family proteins were examined, we found that GILZ overexpression causes induction of the pro-survival protein Bcl-xL. Since siRNA against Bcl-xL reverses GC induced cytoprotection, Bcl-xL induction represents an important event in GILZ-induced cytoprotection. Our data suggest that GILZ functions as a cytoprotective gene in cardiomyocytes. - Highlights: • Corticosteroids act as a cytoprotective agent in cardiomyocytes • Corticosteroids induce GILZ expression in cardiomyocytes • Elevated GILZ results in resistance against apoptosis induced by doxorubicin • GILZ induces Bcl-xL protein without inducing Bcl-xL mRNA.

  10. Beta-irradiation used for systemic radioimmunotherapy induces apoptosis and activates apoptosis pathways in leukaemia cells

    Beta-irradiation used for systemic radioimmunotherapy (RIT) is a promising treatment approach for high-risk leukaemia and lymphoma. In bone marrow-selective radioimmunotherapy, beta-irradiation is applied using iodine-131, yttrium-90 or rhenium-188 labelled radioimmunoconjugates. However, the mechanisms by which beta-irradiation induces cell death are not understood at the molecular level. Here, we report that beta-irradiation induced apoptosis and activated apoptosis pathways in leukaemia cells depending on doses, time points and dose rates. After beta-irradiation, upregulation of CD95 ligand and CD95 receptor was detected and activation of caspases resulting in apoptosis was found. These effects were completely blocked by the broad-range caspase inhibitor zVAD-fmk. In addition, irradiation-mediated mitochondrial damage resulted in perturbation of mitochondrial membrane potential, caspase-9 activation and cytochrome c release. Bax, a death-promoting protein, was upregulated and Bcl-xL, a death-inhibiting protein, was downregulated. We also found higher apoptosis rates and earlier activation of apoptosis pathways after gamma-irradiation in comparison to beta-irradiation at the same dose rate. Furthermore, irradiation-resistant cells were cross-resistant to CD95 and CD95-resistant cells were cross-resistant to irradiation, indicating that CD95 and irradiation used, at least in part, identical effector pathways. These findings demonstrate that beta-irradiation induces apoptosis and activates apoptosis pathways in leukaemia cells using both mitochondrial and death receptor pathways. Understanding the timing, sequence and molecular pathways of beta-irradiation-mediated apoptosis may allow rational adjustment of chemo- and radiotherapeutic strategies. (orig.)

  11. Recovering drug-induced apoptosis subnetwork from Connectivity Map data.

    Yu, Jiyang; Putcha, Preeti; Silva, Jose M

    2015-01-01

    The Connectivity Map (CMAP) project profiled human cancer cell lines exposed to a library of anticancer compounds with the goal of connecting cancer with underlying genes and potential treatments. Since the therapeutic goal of most anticancer drugs is to induce tumor-selective apoptosis, it is critical to understand the specific cell death pathways triggered by drugs. This can help to better understand the mechanism of how cancer cells respond to chemical stimulations and improve the treatment of human tumors. In this study, using CMAP microarray data from breast cancer cell line MCF7, we applied a Gaussian Bayesian network modeling approach and identified apoptosis as a major drug-induced cellular-pathway. We then focused on 13 apoptotic genes that showed significant differential expression across all drug-perturbed samples to reconstruct the apoptosis network. In our predicted subnetwork, 9 out of 15 high-confidence interactions were validated in the literature, and our inferred network captured two major cell death pathways by identifying BCL2L11 and PMAIP1 as key interacting players for the intrinsic apoptosis pathway and TAXBP1 and TNFAIP3 for the extrinsic apoptosis pathway. Our inferred apoptosis network also suggested the role of BCL2L11 and TNFAIP3 as "gateway" genes in the drug-induced intrinsic and extrinsic apoptosis pathways. PMID:25883971

  12. Apoptosis of human pancreatic cancer cells induced by Triptolide

    Guo-Xiong Zhou; Xiao-Ling Ding; Jie-Fei Huang; Hong Zhang; Sheng-Bao Wu; Jian-Ping Cheng; Qun Wei

    2008-01-01

    AIM:To investigate apoptosis in human pancreatic cancer ceils induced by Triptolide (TL),and the relationship between this apoptosis and expression of caspase-3' bcl-2 and bax.METHODS:Human pancreatic cancer cell line SW1990 was cultured in DIEM media for this study.MTT assay was used to determine the cell growth inhibitory rate in vitro.Flow cytometry and TUNEL assay were used to detect the apoptosis of human pancreatic cancer cells before and after TL treatment.RT-PCR was used to detect the expression of apoptosis-associated gene caspase-3' bcl-2 and bax.RESULTS:TL inhibited the growth of human pancreatic cancer cells in a dose-and time-dependent manner.TL induced human pancreatic cancer cells to undergo apoptosis with typically apoptotic characteristics.TUNEL assay showed that after the treatment of human pancreatic cancer cells with 40 ng/mL TL for 12 h and 24 h,the apoptotic rates of human pancreatic cancer cells increased significantly.RT-PCR demonstrated that caspase-3 and bax were significantly up-regulated in SW1990 cells treated with TL while bcl-2 mRNA was not.CONCLUSION:TL is able to induce the apoptosis in human pancreatic cancer cells.This apoptosis may be mediated by up-regulating the expression of apoptosisassociated caspase-3 and bax gene.

  13. Visualizing Vpr-induced G2 arrest and apoptosis.

    Tomoyuki Murakami

    Full Text Available Vpr is an accessory protein of human immunodeficiency virus type 1 (HIV-1 with multiple functions. The induction of G2 arrest by Vpr plays a particularly important role in efficient viral replication because the transcriptional activity of the HIV-1 long terminal repeat is most active in G2 phase. The regulation of apoptosis by Vpr is also important for immune suppression and pathogenesis during HIV infection. However, it is not known whether Vpr-induced apoptosis depends on the ability of Vpr to induce G2 arrest, and the dynamics of Vpr-induced G2 arrest and apoptosis have not been visualized. We performed time-lapse imaging to examine the temporal relationship between Vpr-induced G2 arrest and apoptosis using HeLa cells containing the fluorescent ubiquitination-based cell cycle indicator2 (Fucci2. The dynamics of G2 arrest and subsequent long-term mitotic cell rounding in cells transfected with the Vpr-expression vector were visualized. These cells underwent nuclear mis-segregation after prolonged mitotic processes and then entered G1 phase. Some cells subsequently displayed evidence of apoptosis after prolonged mitotic processes and nuclear mis-segregation. Interestingly, Vpr-induced apoptosis was seldom observed in S or G2 phase. Likewise, visualization of synchronized HeLa/Fucci2 cells infected with an adenoviral vector expressing Vpr clearly showed that Vpr arrests the cell cycle at G2 phase, but does not induce apoptosis at S or G2 phase. Furthermore, time-lapse imaging of HeLa/Fucci2 cells expressing SCAT3.1, a caspase-3-sensitive fusion protein, clearly demonstrated that Vpr induces caspase-3-dependent apoptosis. Finally, to examine whether the effects of Vpr on G2 arrest and apoptosis were reversible, we performed live-cell imaging of a destabilizing domain fusion Vpr, which enabled rapid stabilization and destabilization by Shield1. The effects of Vpr on G2 arrest and subsequent apoptosis were reversible. This study is the first to

  14. Apoptosis of smooth muscle cells induced by radiation

    Objective: To study the effects and mechanism of 188Re on apoptosis of cultured smooth muscle cells (SMCs), and to explore the value of radiation induced SMCs apoptosis for preventing restenosis. Methods: The SMCs cultured in vitro were irradiated by 188Re with different doses. The trypan blue exclusion test, flow cytometry, JAM test, transmission electron microscopy and immunocytochemistry assay were used to investigate the effects of β-particles on apoptosis of SMCs, such as cell viability, cell apoptosis rate, DNA fragmentation, cell ultrastructural changes and related gene expression. Results: There were no significant changes of SMCs viability, cell apoptosis rate, DNA fragmentation and cellular ultrastructure in low-dose irradiation group, compared with control group. High-dose radiation (>2.96 GBq/L) on SMCs showed that viable cell proportion was markedly decreased, while cell apoptosis rate and DNA fragmentation were significantly increased, and cellular ultrastructure was destroyed. The expression of p53, bax gene was up regulated and bcl-2/bax was decreased while SMCs apoptosis occurred. Conclusions: Low-dose radiation on SMCs, which could inhibit completely SMCs proliferation, did not show any effects on cell viability, cell apoptosis rate, cell ultrastructure and DNA fragmentation. High-dose radiation could result in significant SMCs apoptosis. Up-regulated p53, bcl-2 and bax gene took a part in cell apoptosis induced by radiation. Low-dose and low-dose rate radiation appeared to be an ideal intravascular radiotherapy for preventing restenosis, which could not only inhibit SMCs proliferation, but also preserve cell viability and integrity

  15. Paclitaxel sensitizes gastric cancer cells to TRAIL-induced apoptosis

    2015-01-01

    Objective:Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) holds promise for cancer therapy as it has unique capacity to selectively trigger apoptosis in cancer cells. We reported here that paclitaxel sensitized gastric cancer cells to TRAIL-induced apoptosis.Methods: After drug exposure, apoptosis rate and caspase activation were examined. Various proteins were detected by western blot. Several interventions, including pharmacological inhibitors and siRNA transfection were used. hTe growth inhibition of tumors was evaluated in SGC-7901-implanted nude mice model.Results:We found gastric cancer cellsshowed a mixed response to TRAIL. Combined treatment with paclitaxel markedly enhanced TARIL-induced apoptosis in vitro and in vivo. The underlying mechanisms involved in synergistical activation of caspase proteins, up-regulation of receptors, down-regulation of antiapoptotic proteins and inactivation of MAPKs.Conclusion:TRAIL-induced cytotoxicity and apoptosis can be synergistically enhanced by paclitaxel, suggesting the therapeutic potential of combining TARIL plus paclitaxel in gastric cancer treatment.

  16. Apoptosis induced by dioscin in Hela cells.

    Cai, Jing; Liu, Mingjie; Wang, Zhao; Ju, Yong

    2002-02-01

    Dioscin, a saponin extracted from the root of Polygonatum Zanlanscianense Pamp, markedly inhibited proliferation of Hela cells. The results indicated that Hela cells underwent apoptosis in dose- and time-dependent manners when treated with Dioscin. Caspase-3, -8 and -9 activities were also detected. The low enzymatic activity of caspase-8 and high activity of caspase-9 showed that the mitochondrial pathway was activated in apoptosis. The reduced expression of the survival protein Bcl-2 also confirmed this result. These studies may be significant in finding a new drug to treat human cervical cancer. PMID:11853164

  17. The role of hypoxia inducible factor 1 (HIF-1) in hypoxia induced apoptosis

    Greijer, A.E.; Wall, E. van der

    2004-01-01

    Apoptosis can be induced in response to hypoxia. The severity of hypoxia determines whether cells become apoptotic or adapt to hypoxia and survive. A hypoxic environment devoid of nutrients prevents the cell undergoing energy dependent apoptosis and cells become necrotic. Apoptosis regulatory protei

  18. Paris Saponin II induced apoptosis via activation of autophagy in human lung cancer cells.

    Zhang, Lili; Man, Shuli; Wang, Yongshuai; Liu, Jing; Liu, Zhen; Yu, Peng; Gao, Wenyuan

    2016-06-25

    Paris Saponin II (PSII) has been shown anticancer activity against several cancer lines through the pro-apoptotic pathway. The aim of the study was to investigate the relationship between apoptosis and autophagy taking part in the anti-cancer mechanisms of PSII. In this study, PSII induced autophagy and apoptosis in dose- and time-dependent manners. Meanwhile, it induced autophagy as early as 2 h after exposure to 1 μM of PSII accompanying with apoptosis. Blockade of autophagy with chloroquine (CQ) attenuated apoptosis, while regulation of reactive oxygen species (ROS) by N-acetyl cysteine (NAC), gallic acid (GA) and H2O2 could not influence autophagy. In addition, PSII induced apoptosis via activation of autophagy, which might be associated with the activation of JNK and inhibition of PI3K/AKT/mTOR pathway. All in all, our research increased the understanding of the role of PSII regulating autophagy and apoptosis, which would hopefully provide prospective strategies for cancer therapy. PMID:27180204

  19. Effects of phospholipid hepatoprotectors on apoptosis during experimental liver pathology induced by isoniazid and paracetamol.

    Udut, V V; Vengerovsky, A I; Dygai, A M

    2013-03-01

    Phospholipid hepatoprotectors essentiale, eplir, and their combinations with succinic acid decreased the relative content of apoptotic lymphocytes and granulocytes in the blood, content of TNF-α, total and indirect bilirubin, and activities of transaminases and alkaline phosphatase and increase the content of IL-10 in rats with experimental intoxication induced by isoniazid and paracetamol. A combination of eplir and succinic acid was most effective in preventing the development of leukocyte apoptosis. PMID:23658881

  20. HIV-1 protease-induced apoptosis

    Rumlová, Michaela; Křížová, Ivana; Keprová, Alena; Hadravová, Romana; Doležal, Michal; Strohalmová, Karolína; Pichová, Iva; Hájek, Miroslav; Ruml, T.

    2014-01-01

    Roč. 11, May 20 (2014), 37/1-37/15. ISSN 1742-4690 R&D Projects: GA ČR GA204/09/1388 Institutional support: RVO:61388963 Keywords : HIV protease * BCA3 * AKIP-1 * apoptosis * mitochondria Subject RIV: EE - Microbiology, Virology Impact factor: 4.185, year: 2014 http://www.retrovirology.com/content/11/1/37

  1. Cerebral ischemia—induced neuronal apoptosis mediated by nitric oxide

    NomuY

    2002-01-01

    To elucidate the cellular and molecular mechanism of cerebral ischemia-induced neuronal apoptosis mediated by nitric oxide (NO) in the brain,we investigated:(1)cell death in hippocampal CA1 neurons of rats after a rransient four vessel occlusion (4VO)/reperfusion and (2) apoptosis induced by NOC18(NO releaser) using SHSY5Y cells,a human neuroblastoma cell line.We found that 4VO caused expression of inducible type of NO synthase (iNOS) in glial cells and neuronal apoptosis in CA1 region of rats.Next we examined in vitro apoptotic effects of NOC18 on SHSY5Y cells and suggest that NO decrease mitochondrial membrane potential,release cytochrome C from mitochondria,activates caspase-3,degrade inhibitor of caspase-activated DNase(Icad),and activated DNase translocate into nucleus and induce DNA fragmentation.Thus we conclude that the excess amount of NO produced by glial iNOS at cerebral ischemia could be involved in neuronal apoptosis in CA1 region.Regarding NO action on neurons,we further obtained that NO propects neuronal apoptosis in PC12 cells perhaps by nitrosylation of caspase,subsequent reduction of proteolytic activity.Taken together,we suggest that NO seem to exert dual effects(toxic and beneficial) on neuronal apoptosis,the one (toxic);apoptosis-induction throuth the decrease in mitochondrial membrane potentials and cytochrome C release and the othe (beneficial);protection against apoptosis through the inhibition of caspase activity.

  2. The characteristics and mechanism of apoptosis induced by internal irradiation

    Apoptosis in tumor cells induced by radionuclides is likely the most effective way to cure cancer. In order to explore the possibility in clinic application, the characteristics and mechanism of apoptosis induced by internal irradiation were investigated. The apoptosis and expressions of bcl-2mRNA, bcl-2 and bax of K562 cells following internal exposure with different accumulated absorbed doses of strontium-89 were studied. 6 h after irradiation, the characteristics of apoptosis and necrosis appeared in K562 cells. The apoptosis and necrosis enhanced with the prolongation of internally contaminated time at 6 h, 9 h, 12 h, 24 h and 48 h. The expressions of bcl-2mRNA decreased at 12 h, most remarkably at 24 h. The expressions of bcl-2 decreased after irradiation whereas bax had no obvious changes. The results suggest that the apoptosis induced by internal exposure may be regulated by lower expressions of bcl-2mRNA and bcl-2, lower bcl-2/bax value

  3. Neem oil limonoids induces p53-independent apoptosis and autophagy.

    Srivastava, Pragya; Yadav, Neelu; Lella, Ravi; Schneider, Andrea; Jones, Anthony; Marlowe, Timothy; Lovett, Gabrielle; O'Loughlin, Kieran; Minderman, Hans; Gogada, Raghu; Chandra, Dhyan

    2012-11-01

    Azadirachta indica, commonly known as neem, has a wide range of medicinal properties. Neem extracts and its purified products have been examined for induction of apoptosis in multiple cancer cell types; however, its underlying mechanisms remain undefined. We show that neem oil (i.e., neem), which contains majority of neem limonoids including azadirachtin, induced apoptotic and autophagic cell death. Gene silencing demonstrated that caspase cascade was initiated by the activation of caspase-9, whereas caspase-8 was also activated late during neem-induced apoptosis. Pretreatment of cancer cells with pan caspase inhibitor, z-VAD inhibited activities of both initiator caspases (e.g., caspase-8 and -9) and executioner caspase-3. Neem induced the release of cytochrome c and apoptosis-inducing factor (AIF) from mitochondria, suggesting the involvement of both caspase-dependent and AIF-mediated apoptosis. p21 deficiency caused an increase in caspase activities at lower doses of neem, whereas p53 deficiency did not modulate neem-induced caspase activation. Additionally, neem treatment resulted in the accumulation of LC3-II in cancer cells, suggesting the involvement of autophagy in neem-induced cancer cell death. Low doses of autophagy inhibitors (i.e., 3-methyladenine and LY294002) did not prevent accumulation of neem-induced LC3-II in cancer cells. Silencing of ATG5 or Beclin-1 further enhanced neem-induced cell death. Phosphoinositide 3-kinase (PI3K) or autophagy inhibitors increased neem-induced caspase-3 activation and inhibition of caspases enhanced neem-induced autophagy. Together, for the first time, we demonstrate that neem induces caspase-dependent and AIF-mediated apoptosis, and autophagy in cancer cells. PMID:22915764

  4. Interferon-gamma sensitizes colonic epithelial cell lines to physiological and therapeutic inducers of colonocyte apoptosis.

    O'Connell, J

    2012-02-03

    Homeostasis in the colonic epithelium is achieved by a continuous cycle of proliferation and apoptosis, in which imbalances are associated with disease. Inflammatory bowel disease (IBD) and colon cancer are associated with either excessive or insufficient apoptosis of colonic epithelial cells, respectively. By using two colonic epithelial cell lines, HT29 and SW620, we investigated how the epithelial cell\\'s sensitivity to apoptosis was regulated by the proinflammatory cytokine interferon-gamma (IFN-gamma). We found that IFN-gamma sensitized HT29 cells, and to a lesser extent SW620, to diverse inducers of apoptosis of physiologic or therapeutic relevance to the colon. These apoptosis inducers included Fas (CD95\\/APO-1) ligand (FasL), short-chain fatty acids, and chemotherapeutic drugs. The extent of IFN-gamma-mediated apoptosis sensitization in these two cell lines correlated well with the degree of IFN-gamma-mediated upregulation of the proapoptotic protease caspase-1. Although IFN-gamma alone effectively sensitized HT29 cells to apoptosis, inclusion of the protein synthesis inhibitor cyclohexamide (CHX) during apoptotic challenge was necessary for maximal sensitization of SW620. The requirement of CHX to sensitize SW620 cells to apoptosis implies a need to inhibit translation of antiapoptotic proteins absent from HT29. In particular, the antiapoptotic protein Bcl-2 was strongly expressed in SW620 cells but absent from HT29. Our results indicate that IFN-gamma increases the sensitivity of colonic epithelial cells to diverse apoptotic stimuli in concert, via upregulation of caspase-1. Our findings implicate caspase-1 and Bcl-2 as important central points of control determining the general sensitivity of colonic epithelial cells to apoptosis.

  5. Denbinobin induces apoptosis by apoptosis-inducing factor releasing and DNA damage in human colorectal cancer HCT-116 cells.

    Chen, Tzu-Hsuan; Pan, Shiow-Lin; Guh, Jih-Hwa; Chen, Chien-Chih; Huang, Yao-Ting; Pai, Hui-Chen; Teng, Che-Ming

    2008-11-01

    Denbinobin is a phenanthraquinone derivative present in the stems of Ephemerantha lonchophylla. We showed that denbinobin induces apoptosis in human colorectal cancer cells (HCT-116) in a concentration-dependent manner. The addition of a pan-caspase inhibitor (zVAD-fmk) did not suppress the denbinobin-induced apoptotic effect, and denbinobin-induced apoptosis was not accompanied by processing of procaspase-3, -6, -7, -9, and -8. However, denbinobin triggered the translocation of the apoptosis-inducing factor (AIF) from the mitochondria into the nucleus. Small interfering RNA targeting of AIF effectively protected HCT-116 cells against denbinobin-induced apoptosis. Denbinobin treatment also caused DNA damage, activation of the p53 tumor suppressor gene, and upregulation of numerous downstream effectors (p21WAF1/CIP1, Bax, PUMA, and NOXA). A HCT-116 xenograft model demonstrated the in vivo efficacy and low toxicity of denbinobin. Taken together, our findings suggest that denbinobin induces apoptosis of human colorectal cancer HCT-116 cells via DNA damage and an AIF-mediated pathway. These results indicate that denbinobin has potential as a novel anticancer agent. PMID:18607570

  6. Radiation-induced apoptosis in developing rats and kainic acid-induced excitotoxicity in adult rats are associated with distinctive morphological and biochemical c-Jun/AP-1 (N) expression

    Ionizing radiation produces apoptosis in the developing rat brain. Strong c-Jun immunoreactivity, as revealed with the antibody c-Jun/AP-1 (N) which is raised against the amino acids 91-105 mapping with the amino terminal domain of mouse c-Jun p39, is simultaneously observed in the nucleus and cytoplasm of apoptotic cells. Western blotting of total brain homogenates, using the same antibody, shows a p39 band in control rats which is accompanied by a strong, phosphorylated p62 double-band in irradiated animals. In addition, increased c-Jun N-terminal kinase 1 expression, as found on western blots, is found in irradiated rats when compared with controls. Intraperitoneal injection of kainic acid at convulsant doses to the adult rat produces cell death with morphological features of necrosis, together with the appearance of cells with fine granular chromatin degeneration and small numbers of apoptotic-like cells, in the entorhinal and piriform cortices, basal amygdala, certain thalamic nuclei, and CA1 region of the hippocampus. c-Jun expression in kainic acid-treated rats, as revealed with the c-Jun/AP-1 (N) antibody, is found in the nuclei of a minority of cells in the same areas. The vast majority of c-Jun-immunoreactive cells have normal nuclear morphology, whereas necrotic cells are negative and only a few cells with fine granular chromatin condensation and apoptotic cells following kainic acid injection are stained with c-Jun antibodies. Western blotting, using the same antibody, shows a p39 band in control rats, which is accompanied by a band at about p26 from 6 h onwards following kainic acid injection. Decreased c-Jun N-terminal kinase 1 expression, as revealed on western blots, is observed in kainic acid-treated rats.These results show that the antibody c-Jun/AP-1 (N) recognizes three different forms of c-Jun-related immunoreactivity in normal and pathological states, which are associated with the different outcome of cells. These results stress the necessity

  7. Role of endoplasmic reticular stress in aortic endothelial apoptosis induced by intermittent/persistent hypoxia

    YANG Yuan-yuan; SHANG Jin; LIU Hui-guo

    2013-01-01

    Background Accumulated evidence shows that hypoxia can induce endothelial apoptosis,however the mechanism is still unknown.We hypothesized whether intermittent or persistent hypoxia could induce endoplasmic reticular stress,leading to endothelial apoptosis.Methods Twenty-four 8-week male Sprague Dawley (SD) rats were divided into three groups:normoxia (NC) group,intermittent hypoxia (IH) group and persistent hypoxia (PH) group.TUNEL staining was performed to detect aortic arch endotheliar apoptosis,and immunohistochemistry for BIP,CHOP and caspase12 to test protein expression;human umbilical vein endothelial cells (HUVECs) of the line ECV304 were cultured (with or without taurodeoxycholic acid (TUDCA) 10 mmol/L,100 mmol/L) and divided into four groups:NC group (20.8% O2 for 4 hours),PH1 group (5% O2 for 4 hours),PH2 group (5% O2 for 12 hours) and IH group (20.8% O2 and 5% O2 alternatively for 8 hours).Annexin V-fluorescein-isothiocyanate/propidium iodide flow cytometry was used to assess apoptosis in each group.The expressions of GRP78,CHOP and caspase12 were detected by real-time quantitative reverse-transcription PCR.Result Intermittent and persistent hypoxia could increase the rate of endothelium apoptosis and the expressions of GRP78,CHOP and caspase12 compared with the control,induction by intermittent hypoxia was slightly higher than persistent hypoxia.In the HUVEC experiment,TUDCA significantly reduced apoptosis and the expressions of GRP78,CHOP and caspase12.Conclusion Hypoxia,especially intermittent,can induce endothelial cell apoptosis possibly through endoplasmic reticulum stress pathway,which can be attenuated by taurodeoxycholic acid.

  8. Nanoparticle-Mediated Mitochondrial Damage Induces Apoptosis in Cancer.

    Mallick, Abhik; More, Piyush; Syed, Muhammed Muazzam Kamil; Basu, Sudipta

    2016-06-01

    Detouring of conventional DNA damaging anticancer drugs into mitochondria to damage mitochondrial DNA is evolving as a promising strategy in chemotherapy. Inhibiting single target in mitochondria would eventually lead to the emergence of drug resistance. Moreover, targeting mitochondria selectively in cancer cells, keeping them intact in healthy cells, remains a major challenge. Herein, triphenylphosphine (TPP)-coated positively charged 131.6 nm spherical nanoparticles (NPs) comprised of α-tocopheryl succinate (TOS, inhibitor of complex II in electron transport chain) and obatoclax (Obt, inhibitor of Bcl-2) were engineered. The TOS-TPP-Obt-NPs entered into acidic lysosomes via macropinocytosis, followed by lysosomal escape and finally homed into mitochondria over a period of 24 h. Subsequently, these TOS-TPP-Obt-NPs triggered mitochondrial outer membrane permeabilization (MOMP) by inhibiting antiapoptotic Bcl-2, leading to Cytochrome C release. These TOS-TPP-Obt-NPs mediated mitochondrial damage induced cellular apoptosis through caspase-9 and caspase-3 cleavage to show improved efficacy in HeLa cells. Moreover, TOS-TPP-Obt-NPs induced MOMP in drug-resistant triple negative breast cancer cells (MDA-MB-231), leading to remarkable efficacy, compared to the combination of free drugs in higher drug concentrations. Results presented here clearly stimulate the usage of multiple drugs to perturb simultaneously diverse targets, selectively in mitochondria, as next-generation cancer therapeutics. PMID:27160664

  9. Sulforaphane reverses glucocorticoid-induced apoptosis in osteoblastic cells through regulation of the Nrf2 pathway

    Lin H

    2014-07-01

    Full Text Available Hao Lin,1,* Bo Wei,1,* Guangsheng Li,1 Jinchang Zheng,1 Jiecong Sun,1 Jiaqi Chu,2 Rong Zeng,1 Yanru Niu21Department of Spinal Surgery, Affiliated Hospital of Guangdong Medical College, Zhanjiang, People’s Republic of China; 2Laboratory Institute of Minimally Invasive Orthopedic Surgery, Affiliated Hospital of Guangdong Medical College, Zhanjiang, People’s Republic of China *These authors contributed equally to this work Abstract: Apoptosis of osteoblasts triggered by high-dose glucocorticoids (GCs has been identified as a major cause of osteoporosis. However, the underlying molecular mechanisms accounting for this action remain elusive, which has impeded the prevention and cure of this side effect. Sulforaphane (SFP is a naturally occurring isothiocyanate that has huge health benefits for humans. In this study, by using osteoblastic MC3T3-E1 cells as a model, we demonstrate the protective effects of SFP against dexamethasone (Dex-induced apoptosis and elucidate the underlying molecular mechanisms. The results show that SFP could effectively inhibit the Dex-induced growth inhibition and release of lactate dehydrogenase in MC3T3-E1 cells. Treatment with Dex induced caspase-dependent apoptosis in MC3T3-E1 cells, as evidenced by an increase in the Sub-G1 phase, chromatin condensation, and deoxyribonucleic acid fragmentation, which were significantly suppressed by coincubation with SFP. Mitochondria-mediated apoptosis pathway contributed importantly to Dex-induced apoptosis, as revealed by the activation of caspase-3/-9 and subsequent cleavage of poly adenosine diphosphate ribose polymerase, which was also effectively blocked by SFP. Moreover, treatments of Dex strongly induced overproduction of reactive oxygen species and inhibited the expression of nuclear factor erythroid 2-related factor 2 (Nrf2 and the downstream effectors HO1 and NQO1. However, cotreatment with SFP effectively reversed this action of Dex. Furthermore, silencing of Nrf2 by

  10. Iron dysregulation combined with aging prevents sepsis-induced apoptosis

    Javadi, Pardis; Buchman, Timothy G.; Stromberg, Paul E.; Turnbull, Isaiah R.; Vyas, Dinesh; Hotchkiss, Richard S.; Karl, Irene E.; Coopersmith, Craig M.

    2005-01-01

    Background Sepsis, iron loading and aging cause independent increases in gut epithelial and splenic apoptosis. It is unknown how their combination will affect apoptosis and systemic cytokine levels. Methods Hfe−/− mice (a murine homolog of hemochromatosis) abnormally accumulate iron in their tissues. Aged (24–26 months) or mature (16–18 months) Hfe−/− mice and wild type (WT) littermates were subjected to cecal ligation and puncture (CLP) or sham laparotomy. Intestine, spleen, and blood were harvested 24 hours later and assessed for apoptosis and cytokine levels. Results Gut epithelial and splenic apoptosis were low in both aged septic and sham Hfe−/− mice, regardless of the amount of iron in their diet. Mature septic WT mice had increased apoptosis compared to age-matched sham WT mice. Mature septic Hfe−/− mice had similar levels of intestinal cell death to age-matched septic WT mice but higher levels of splenic apoptosis. Apoptosis was significantly lower in septic aged Hfe−/− mice than septic mature Hfe−/− animals. Interleukin-6 was elevated in septic aged Hfe−/− mice compared to sham mice. Conclusions Although sepsis, chronic iron dysregulation, and aging each increase gut and splenic apoptosis, their combination yields cell death levels similar to sham animals despite the fact that aged Hfe−/− mice are able to mount an inflammatory response following CLP and mature Hfe−/− mice have elevated sepsis-induced apoptosis. Combining sepsis with two risk factors that ordinarily increase cell death and increase mortality in CLP yields an apoptotic response that could not have been predicted based upon each element in isolation. PMID:15921699

  11. A bifunctional organometallic ruthenium drug with multiple modes of inducing apoptosis.

    Chatterjee, Soumya; Biondi, Ilaria; Dyson, Paul J; Bhattacharyya, Arindam

    2011-06-01

    The organometallic glutathione S-transferase inhibitor ruthenium(II) (ethacrynic acid-η(6)-benzylamide)(1,3,5-triaza-7-phosphaadamantane) dichloride, termed ethaRAPTA, has been demonstrated to induce apoptosis in the cisplatin-resistant MCF-7 breast cancer cell line. Probing the molecular basis of this activity suggests that the complex triggers multiple pathways toward apoptosis, including those involving endonuclease G, caspases, and c-Jun N-terminal kinase, which could provide a therapy for multi-drug-resistant tumors. Furthermore, the induction of heat shock protein 70 expression enhances selectivity of the complex for tumor cells, reducing the general toxicity. PMID:21437708

  12. pACC1 peptide loaded chitosan nanoparticles induces apoptosis via reduced fatty acid synthesis in MDA-MB-231 cells

    Kaliaperumal, Jagatheesh; Hari, Natarajan; Pavankumar, Padarthi; Elangovan, Namasivayam

    2016-06-01

    The development of formulations with therapeutic peptides has been restricted to poor cell penetration and in this attempt; we developed pACC1 peptide loaded chitosan nanoparticles. The prepared nanoparticles were characterized with FT-IR, XRD, SEM and TEM. In addition, the suitable formulation was evaluated for hemocompatibility, plasma stability and embryo toxicity using Danio rerio embryo model. The results showed that pACC1 peptide loaded chitosan nanoparticles were compatible with plasma. They possess sustained release pattern and also found to be safe up to 300 mg/L in embryo toxicity tests. Cytotoxicity assays with MDA-MB-231 cell lines suggested that, pACC1 peptide loaded chitosan nanoparticles were capable of enhanced cellular penetration and reduced palmitic acid content, which was confirmed by H1 NMR. Hence, these nanoparticles could be employed as excellent adjuvant therapeutics while treating solid tumors with multi-drug resistance.

  13. The role of Fas in radiation induced apoptosis in vivo

    Kim, Sung Hee; Seong, Jin Sil; Seong, Je Kyung [Yonsei University Medical College, Seoul (Korea, Republic of)

    2002-09-15

    It has been recognized that interaction of the Fas: Fas ligand plays an important role in radiation-induced apoptosis. The purpose of this study was to investigate the role of Fas mutation in radiation-induced apoptosis in vivo. Mice with mutations in Fas, MRL/Mpj Fas{sup lpr}, and its normal control, MRL/Mpj, were used in this study. Eight-week old male mice were given whole body radiation. After irradiation, the mice were killed and their spleens were collected at different time intervals. Tissue samples were stained with hematoxylin-eosin and the numbers of apoptotic cells were scored. Regulating molecules of apoptosis including p53, Bcl-2, Bax, Bcl-X{sub L}, and Bcl-X{sub s} were also analyzed by Western blotting. At 25 Gy irradiation, the level of apoptosis reached the peak value at 8 hr after radiation and recovered to the normal value at 24 hr after radiation in MRL/Mpj mice. In contrast, the peak apoptosis level appeared at 4 hr after radiation in MRL/Mpj-Fas{sup lpr} mice. At 8 hr after radiation, the levels of apoptosis in MRL/Mpj mice and MRL/Mpj-Fas{sup lpr} mice were 52.3 {+-} 7.8% and 8.0 {+-} 8.6%, respectively ({rho} < 0.05). The expression of apoptosis regulating molecules, p53, Bcl-X{sub L}, and Bcl-X{sub s}, increased in MRL/Mpj mice in response to radiation; p53 with a peak level of 3-fold at 8 h, Bcl-X{sub L} with a peak level of 3.3-fold at 12 h, and Bcl-X{sub s} with a peak level of 3-fold at 12 h after 25 Gy radiation. Bcl-2 and Bax did not show significant change in MRL/Mpj mice. However in MRL/Mpj-Fas{sup lpr} mice, the expression levels of p53, Bcl-2, Bax, Bcl-X{sub L}, and Bcl-X{sub s} showed no significant change. The level of radiation-induced apoptosis was lower in Fas mutated mice, lpr, than in control mice. This seemed to be related to the lack of radiation-induced p53 activation in the lpr mice. This result suggests that Fas plays an important role in radiation-induced apoptosis in vivo.

  14. Induction of apoptosis in prostate cancer cells by pachymic acid from Poria cocos

    Pachymic acid (PA) is a natural triterpenoid known to inhibit the phospholipase A2 (PLA2) family of arachidonic acid (AA)-producing enzymes. PLA2 is elevated in prostatic adenocarcinoma and conversion of AA to prostaglandins leads to AKT pro-survival activity. In this study, we investigated the effect of PA on the growth of human prostate cancer cells. PA significantly reduced cell proliferation and induced apoptosis in a dose- and time-dependent fashion, with androgen-insensitive DU145 prostate cancer cells showing greater growth inhibition relative to androgen-responsive LNCaP. Despite elevated protein expression of the cell cycle inhibitor, p21, apoptosis occurred in the absence of cell cycle arrest. PA-treatment decreased Bad phosphorylation, increased Bcl-2 phosphorylation, and activated caspases-9 and -3, suggesting that PA initiated apoptosis through mitochondria dysfunction. PA-treatment also decreased the expression and activation of proteins within the AKT signal pathway. We speculate that PA influenced apoptosis by reducing prostaglandin synthesis and AKT activity

  15. Cystamine induces AIF-mediated apoptosis through glutathione depletion.

    Cho, Sung-Yup; Lee, Jin-Haeng; Ju, Mi-kyeong; Jeong, Eui Man; Kim, Hyo-Jun; Lim, Jisun; Lee, Seungun; Cho, Nam-Hyuk; Park, Hyun Ho; Choi, Kihang; Jeon, Ju-Hong; Kim, In-Gyu

    2015-03-01

    Cystamine and its reduced form cysteamine showed protective effects in various models of neurodegenerative disease, including Huntington's disease and Parkinson's disease. Other lines of evidence demonstrated the cytotoxic effect of cysteamine on duodenal mucosa leading to ulcer development. However, the mechanism for cystamine cytotoxicity remains poorly understood. Here, we report a new pathway in which cystamine induces apoptosis by targeting apoptosis-inducing factor (AIF). By screening of various cell lines, we observed that cystamine and cysteamine induce cell death in a cell type-specific manner. Comparison between cystamine-sensitive and cystamine-resistant cell lines revealed that cystamine cytotoxicity is not associated with unfolded protein response, reactive oxygen species generation and transglutaminase or caspase activity; rather, it is associated with the ability of cystamine to trigger AIF nuclear translocation. In cystamine-sensitive cells, cystamine suppresses the levels of intracellular glutathione by inhibiting γ-glutamylcysteine synthetase expression that triggers AIF translocation. Conversely, glutathione supplementation completely prevents cystamine-induced AIF translocation and apoptosis. In rats, cysteamine administration induces glutathione depletion and AIF translocation leading to apoptosis of duodenal epithelium. These results indicate that AIF translocation through glutathione depletion is the molecular mechanism of cystamine toxicity, and provide important implications for cystamine in the neurodegenerative disease therapeutics as well as in the regulation of AIF-mediated cell death. PMID:25549939

  16. Study of progesterone mechanisms in radio-induced apoptosis prevention

    The purpose of this work was to study the modulation of radiation-induced cell death of human mammary tumoral cells by progesterone. On the one hand, we observed that progesterone protects cells against radiation-induced apoptosis and increases the proportion of surviving and proliferating damaged cells. On the other hand, a transcriptome analysis was undertaken in irradiated cells treated by progesterone, using DNA micro-arrays. This let us highlight several transcriptional dis-regulations that are likely to explain the protective effect of the hormone; in particular, we showed that progesterone regulates the expression of genes implicated in apoptosis signaling by death receptors. Knowing the crucial role of hormonal control and of apoptosis regulation in breast cancer initiation, our results may help to achieve a better understanding of the implication of progesterone in mammary carcinogenesis. (author)

  17. Radiation-induced apoptosis in thymocytes: pH sensitization

    Thymocytes were used as a model system to study the effect of microenvironmental pH changes on the radiation-induced apoptosis. We found that the sensitivity of thymocytes toward radiation induced apoptosis is increased by increasing the pH of the incubation medium. The major sensitivity change occurs between pH 7 and 8. In a given cell suspension the results obtained were similar when the apoptosis evaluation was carried out either by counting the picnotic nuclei, or monitoring the fraction of apoptic nuclei by flow cytometry; both methods show a radiosensitization when the pH value of incubation media rises from 7 to 8. These results may be important when 'in vitro' experiments are performed with lymphoid cells, since changes in pH of the media may determine important changes in the results. (orig.)

  18. Cyclooxygenase-2 level and culture conditions influence NS398-induced apoptosis and caspase activation in lung cancer cells.

    Chang, H C; Weng, C F

    2001-01-01

    Cyclooxygenases (COXs) catalyze the synthesis of prostaglandins (PGs) from arachidonic acid. Overexpression of COX-2 is frequently found in human cancers and is suggested to play an important role in tumorigenesis. Recent studies indicated that COX-2 inhibitors exert potent anti-cancer effects on a number of cancers. Interestingly, some COX-2 inhibitors potently induce apoptosis, while other COX-2 inhibitors primarily induce growth inhibition. Therefore, there is a variability in the effects that different COX-2 inhibitors have on cancer cells. In this study, we demonstrated that induction of apoptosis of high COX-2-expressing A549 lung cancer cells by a specific COX-2 inhibitor NS398 was observed in cells cultured under serum-free condition. However, this drug induced G1 growth arrest rather than apoptosis in A549 cells maintained in 10% serum medium. Conversely, low COX-2-expressing H226 lung cancer cells were resistant to NS398-induced apoptosis under both serum-free and serum-containing conditions. Moreover, our results showed that NS398-induced apoptosis is associated with activation of caspase-3, a cysteine protease that plays a crucial role in the execution phase of apoptosis. These results suggest that the cytotoxic effect of COX-2 inhibitors on cancer cells may be influenced by extracellular environments and the anti-cancer action of these inhibitors in vivo needs careful evaluation. Additionally, a correlation between the level of COX-2 expression and the extent of apoptosis induced by COX-2 inhibitors was found. PMID:11605058

  19. Glutathione peroxidase-1 protects from CD95-induced apoptosis.

    Gouaze, Valerie; Andrieu-Abadie, Nathalie; Cuvillier, Olivier; Malagarie-Cazenave, Sophie; Frisach, Marie-Francoise; Mirault, Marc-Edouard; Levade, Thierry

    2002-11-01

    Through the induction of apoptosis, CD95 plays a crucial role in the immune response and the elimination of cancer cells. Ligation of CD95 receptor activates a complex signaling network that appears to implicate the generation of reactive oxygen species (ROS). This study investigated the place of ROS production in CD95-mediated apoptosis and the role of the antioxidant enzyme glutathione peroxidase-1 (GPx1). Anti-CD95 antibodies triggered an early generation of ROS in human breast cancer T47D cells that was blocked by overexpression of GPx1 and inhibition of initiator caspase activation. Enforced expression of GPx1 also resulted in inhibition of CD95-induced effector caspase activation, DNA fragmentation, and apoptotic cell death. Resistance to CD95-mediated apoptosis was not due to an increased expression of anti-apoptotic molecules and could be reversed by glutathione-depleting agents. In addition, whereas the anti-apoptotic protein Bcl-xL prevented CD95-induced apoptosis in MCF-7 cells, it did not inhibit the early ROS production. Moreover, Bcl-xL but not GPx1 overexpression could suppress the staurosporine-induced late generation of ROS and subsequent cell death. Altogether, these findings suggest that GPx1 functions upstream of the mitochondrial events to inhibit the early ROS production and apoptosis induced by CD95 ligation. Finally, transgenic mice overexpressing GPx1 were partially protected from the lethal effect of anti-CD95, underlying the importance of peroxide formation (and GPx1) in CD95-triggered apoptosis. PMID:12221075

  20. MG132, a proteasome inhibitor, induces apoptosis in tumor cells.

    Guo, Na; Peng, Zhilan

    2013-03-01

    The balance between cell proliferation and apoptosis is critical for normal development and for the maintenance of homeostasis in adult organisms. Disruption of this balance has been implicated in a large number of disease processes, ranging from autoimmunity and neurodegenerative disorders to cancer. The ubiquitin-proteasome pathway, responsible for mediating the majority of intracellular proteolysis, plays a crucial role in the regulation of many normal cellular processes, including the cell cycle, differentiation and apoptosis. Apoptosis in cancer cells is closely connected with the activity of ubiquitin-proteasome pathway. The peptide-aldehyde proteasome inhibitor MG132 (carbobenzoxyl-L-leucyl-L-leucyl-L-leucine) induces the apoptosis of cells by a different intermediary pathway. Although the pathway of induction of apoptosis is different, it plays a crucial role in anti-tumor treatment. There are many cancer-related molecules in which the protein levels present in cells are regulated by a proteasomal pathway; for example, tumor inhibitors (P53, E2A, c-Myc, c-Jun, c-Fos), transcription factors (transcription factor nuclear factor-kappa B, IκBα, HIFI, YYI, ICER), cell cycle proteins (cyclin A and B, P27, P21, IAP1/3), MG132 induces cell apoptosis through formation of reactive oxygen species or the upregulation and downregulation of these factors, which is ultimately dependent upon the activation of the caspase family of cysteine proteases. In this article we review the mechanism of the induction of apoptosis in order to provide information required for research. PMID:22897979

  1. Radiation-induced cerebral cell apoptosis in rats

    Objective: To study the influence of radiation on rat cerebral cells including neurons and gliocytes. Methods: The rats were divided into control group and X-ray radiation groups with different doses. The apoptosis of cells at different time points after radiation was observed by optic microscopy, electron microscopy and DNA agarose gel electrophoresis. The double label method (in situ end-labeling of DNA strand breaks for labeling apoptotic cells, and immunohistochemistry for labeling cell type) was used to label apoptotic neurons and gliocytes cells separately. Results: The distinct morphological features of apoptosis and the DNA fragmentation ladders on agarose gel electrophoresis were seen in radiation groups. The rate of apoptosis in the adult rat brain was low. There were many apoptotic glial cells (about 93%) and a few apoptotic neurons (about 5%) after radiation. The apoptotic rate in high dose group was higher than that in low dose group. Conclusion: Apoptosis can be induced by radiation in rat brain, the apoptotic rate increases with a increasing dose in the range of 2-8 Gy. The gliocytes are more sensitive to radiation-induced apoptosis than the neurons

  2. Isoflurane-induced neuronal apoptosis in developing hippocampal neurons

    Hongliang Liu; Tijun Dai; Weitao Guo

    2013-01-01

    We hypothesized that the P2X7 receptor may be the target of isoflurane, so we investigated the roles of the P2X7 receptor and inositol triphosphate receptor in calcium overload and neuronal apoptosis induced by isoflurane in cultured embryonic rat hippocampal neurons. Results showed that isoflurane induced widespread neuronal apoptosis and significantly increased cytoplasmic Ca2+. Blockade of P2X7 receptors or removal of extracellular Ca2+ combined with blockade of inositol triphosphate receptors completely inhibited apoptosis or increase in cytoplasmic Ca2+. Removal of extracellular Ca2+ or blockade of inositol triphosphate receptor alone could partly inhibit these effects of isoflurane. Isoflurane could directly activate P2X7-gated channels and induce inward currents, but did not affect the expression of P2X7 receptor protein in neurons. These findings indicate that the mechanism by which isoflurane induced neuronal apoptosis in rat developing brain was mediated by intracellular calcium overload, which was caused by P2X7 receptor mediated calcium influx and inositol triphosphate receptor mediated calcium release.

  3. The role of Fas in radiation induced apoptosis in vivo

    It has been recognized that interaction of the Fas: Fas ligand plays an important role in radiation-induced apoptosis. The purpose of this study was to investigate the role of Fas mutation in radiation-induced apoptosis in vivo. Mice with mutations in Fas, MRL/Mpj Faslpr, and its normal control, MRL/Mpj, were used in this study. Eight-week old male mice were given whole body radiation. After irradiation, the mice were killed and their spleens were collected at different time intervals. Tissue samples were stained with hematoxylin-eosin and the numbers of apoptotic cells were scored. Regulating molecules of apoptosis including p53, Bcl-2, Bax, Bcl-XL, and Bcl-Xs were also analyzed by Western blotting. At 25 Gy irradiation, the level of apoptosis reached the peak value at 8 hr after radiation and recovered to the normal value at 24 hr after radiation in MRL/Mpj mice. In contrast, the peak apoptosis level appeared at 4 hr after radiation in MRL/Mpj-Faslpr mice. At 8 hr after radiation, the levels of apoptosis in MRL/Mpj mice and MRL/Mpj-Faslpr mice were 52.3 ± 7.8% and 8.0 ± 8.6%, respectively (ρ L, and Bcl-Xs, increased in MRL/Mpj mice in response to radiation; p53 with a peak level of 3-fold at 8 h, Bcl-XL with a peak level of 3.3-fold at 12 h, and Bcl-Xs with a peak level of 3-fold at 12 h after 25 Gy radiation. Bcl-2 and Bax did not show significant change in MRL/Mpj mice. However in MRL/Mpj-Faslpr mice, the expression levels of p53, Bcl-2, Bax, Bcl-XL, and Bcl-Xs showed no significant change. The level of radiation-induced apoptosis was lower in Fas mutated mice, lpr, than in control mice. This seemed to be related to the lack of radiation-induced p53 activation in the lpr mice. This result suggests that Fas plays an important role in radiation-induced apoptosis in vivo

  4. Survivin S81A Enhanced TRAIL's Activity in Inducing Apoptosis

    Ferry Sandra

    2010-12-01

    Full Text Available BACKGROUND: Survivin is rarely expressed in normal healthy adult tissues, however, it is upregulated in the majority of cancers. Survivin, which belongs to IAPs family, has been widely reported to protect cells from apoptosis by inhibiting caspases pathway. Survivin’s mitotic activity is modulated by many kinases, and its phosphor status can also influence its ability to inhibit apoptosis. There are several important survivin’s phosphorylation sites, such as S20 and T34. We have continued our investigation on other potential survivin’s phosphorylation sites that could be important site for regulating survivin’s cyto-protection. METHODS: By assuming that S81 could be a potential target to modify activity of survivin, wild-type survivin (Survivin, antisense survivin (Survivin-AS, mutated-survivin Thr34Ala (Survivin-T34A and mutated-survivin Ser81Ala (Survivin-S81A were constructed and inserted into pMSCV-IRES-GFP vector with cytomegalovirus (CMV promoter. Each retroviral product was produced in BOSC23 cells. LY294002 pretreatment and TRAIL treatment along with infection of retroviral products were performed in murine fibrosarcoma L929 cells. For analysis, flow cytometric apoptosis assay and western blot were performed. RESULTS: In our present study, survivin for providing cytoprotection was regulated by PI3K. The results showed that LY294002, an inhibitor of PI3K, effectively suppressed survivin-modulated cytoprotection in a TRAIL-induced apoptotic model. In addition, mutated survivin S81A showed marked suppression on survivin’s cytoprotection. Along with that, TRAIL’s apoptotic activity was enhanced for inducing apoptosis. CONCLUSIONS: We suggested that survivin could inhibit apoptosis through PI3K and S81A could be another potential target in order to inhibit Survivin-modulated cytoprotection as well as to sensitize efficacy of TRAIL or other related apoptotic inducers. KEYWORDS: apoptosis, survivin, TRAIL, S81A, L929, LY294002.

  5. Hypoxia preconditioning protects corneal stromal cells against induced apoptosis

    Xing, Dongmei; Sun, Xingcai; Li, Jinhua; CUI, MIAO; Tan-Allen, Kah; Bonanno, Joseph A

    2005-01-01

    The purpose of this study, was to determine whether hypoxia preconditioning can protect corneal stromal cells from UV stress and cytokine mediated apoptosis. Two models were implemented. First, primary cultured bovine corneal fibroblasts were preconditioned with 0.5–1.5% O2 for 4 hr and stressed with UV-irradiation or stimulation of Fas receptor. Second, bovine eyes were preconditioned with 0.5% O2 for 4 hr and stressed by epithelial scraping to induce anterior keratocyte apoptosis. Cell fate...

  6. The role of hypoxia inducible factor 1 (HIF-1) in hypoxia induced apoptosis

    Greijer, A.E.; Wall

    2004-01-01

    Apoptosis can be induced in response to hypoxia. The severity of hypoxia determines whether cells become apoptotic or adapt to hypoxia and survive. A hypoxic environment devoid of nutrients prevents the cell undergoing energy dependent apoptosis and cells become necrotic. Apoptosis regulatory proteins are delicately balanced. In solid tumours, hypoxia is a common phenomenon. Cells adapt to this environmental stress, so that after repeated periods of hypoxia, selection for resistance to hypoxi...

  7. The role of hypoxia inducible factor 1 (HIF-1) in hypoxia induced apoptosis

    2004-01-01

    Apoptosis can be induced in response to hypoxia. The severity of hypoxia determines whether cells become apoptotic or adapt to hypoxia and survive. A hypoxic environment devoid of nutrients prevents the cell undergoing energy dependent apoptosis and cells become necrotic. Apoptosis regulatory proteins are delicately balanced. In solid tumours, hypoxia is a common phenomenon. Cells adapt to this environmental stress, so that after repeated periods of hypoxia, selection for resistance to hypoxi...

  8. Lonidamine induces apoptosis in drug-resistant cells independently of the p53 gene.

    Del Bufalo, D; Biroccio, A; Soddu, S; Laudonio, N; D'Angelo, C.; Sacchi, A; Zupi, G.

    1996-01-01

    Lonidamine, a dichlorinated derivative of indazole-3-carboxylic acid, was shown to play a significant role in reversing or overcoming multidrug resistance. Here, we show that exposure to 50 microg/ml of lonidamine induces apoptosis in adriamycin and nitrosourea-resistant cells (MCF-7 ADR(r) human breast cancer cell line, and LB9 glioblastoma multiform cell line), as demonstrated by sub-G1 peaks in DNA content histograms, condensation of nuclear chromatin, and internucleosomal DNA fragmentatio...

  9. Lipopolysaccharide-Induced Apoptosis of Astrocytes: Therapeutic Intervention by Minocycline.

    Sharma, Arpita; Patro, Nisha; Patro, Ishan K

    2016-05-01

    Astrocytes are most abundant glial cell type in the brain and play a main defensive role in central nervous system against glutamate-induced toxicity by virtue of numerous transporters residing in their membranes and an astrocyte-specific enzyme glutamine synthetase (GS). In view of that, a dysregulation in the astrocytic activity following an insult may result in glutamate-mediated toxicity accompanied with astrocyte and microglial activation. The present study suggests that the lipopolysaccharide (LPS)-induced inflammation results in significant astrocytic apoptosis compared to other cell types in hippocampus and minocycline could not efficiently restrict the glutamate-mediated toxicity and apoptosis of astrocytes. Upon LPS exposure 76 % astrocytes undergo degeneration followed by 44 % oligodendrocytes, 26 % neurons and 10 % microglia. The pronounced astrocytic apoptosis resulted from the LPS-induced glutamate excitotoxicity leading to their hyperactivation as evident from their hypertrophied morphology, glutamate transporter 1 upregulation and downregulation of GS. Therapeutic minocycline treatment to LPS-infused rats efficiently restricted the inflammatory response and degeneration of other cell types but could not significantly combat with the apoptosis of astrocytes. Our study demonstrates a novel finding on cellular degeneration in the hippocampus revealing more of astrocytic death and suggests a more careful consideration on the protective efficacy of minocycline. PMID:26188416

  10. Recombinant soluble TRAIL induces apoptosis of cancer cells

    2001-01-01

    TRAIL is a tumor necrosis factor family member that selectively induces apoptosis of cancer cells but not of normal cells. To develop TRAIL into a potential cancer drug, three different sizes of soluble TRAIL fragments, including sTRAIL(74-281), sTRAIL(95-281) and sTRAIL(101-281), were expressed in E. coli and purified to homogeneity. Apoptosis assays indicated that sTRAIL(95-281) and sTRAIL(101-281), but not sTRAIL(74-281), can potently induce apoptosis of various cancer cell lines in 6 h, suggesting that the N-terminal fragment of aa101 has inhibitory effect on TRAIL-induced apoptosis. Moreover, we found that some cancer cells were resistant to TRAIL and the resistant cells could be converted into sensitive cells by treatment with the protein synthesis inhibitor cycloheximide, suggesting that one or more short-lived proteins are responsible for cells' resistance to TRAIL.

  11. Phytoconstituents as apoptosis inducing agents: strategy to combat cancer.

    Kumar, Manish; Kaur, Varinder; Kumar, Subodh; Kaur, Satwinderjeet

    2016-08-01

    Advancement in the field of cancer molecular biology has aided researchers to develop various new chemopreventive agents which can target cancer cells exclusively. Cancer chemopreventive agents have proficiency to inhibit, reverse and delay process of carcinogenesis during its early and later course. Chemopreventive agents can act as antioxidative, antimutagenic/antigenotoxic, anti-inflammatory agents or via aiming various molecular targets in a cell to induce cell death. Apoptosis is a kind of cell death which shows various cellular morphological alterations such as cell shrinkage, blebbing of membrane, chromatin condensation, DNA fragmentation, formation of apoptotic bodies etc. Nowadays, apoptosis is being one of the new approaches for the identification and development of novel anticancer therapies. For centuries, plants are known to play part in daily routine from providing food to management of human health. In the last two decades, diverse phytochemicals and various botanical formulations have been characterized as agents that possess potential to execute cancer cells via inducing apoptosis. Data obtained from the research carried out globally pointed out that natural products are the potential candidates which have capability to combat cancer. In the present review, we surveyed literature on natural products which throws light on the mechanism through which these phytochemicals induce apoptosis in cancer cells. PMID:26239338

  12. Coxsackievirus B3-induced apoptosis and Caspase-3

    JIAN PING YUAN; WEI ZHAO; HONG TAO WANG; KAI YU WU; TAO LI; XIAO KUI GUO; SHAN QING TONG

    2003-01-01

    Cell death can be classified into two categories: apoptosis and necrosis. Apoptotic pathway can beeither caspase-dependent or caspase-independent. Caspase-independent cytopathic effect (CPE) has beendescribed. In order to evaluate the pattern of HeLa cell death induced by Coxsackievirus B3 (CVB3)and whether apoptosis involves caspase activation, we co-cultivated HeLa cells with CVB3 and detectedthe cytopathic changes, the alteration of mRNA and protein expression of caspase-3 gene plus caspase-3activity, as well as analyzing DNA fragmentation before and after caspase-3 activity inhibition. Accordingto the results, we propose that CVB3 may induce apoptosis and necrosis in HeLa cells, the latter appearingmuch earlier. Caspase-3 is activated at the levels of both transcription and translation, and procaspase-3 isproteolytically cleaved, thus leading to the continuous increasing of both caspase-3 precursor protein and itssubunit. However, besides CPE, apoptosis induced by CVB3 is not a direct consequence of the activationof caspase-3, or caspase-3 is not the only effector molecule in apoptotic cell death, for caspase-3 inhibitorcan not decrease DNA fragmentation. Some other biochemical mechanisms may participate in the process,whose role weakens the effect of inhibiting caspase-3 activity.

  13. Autophagy inhibition enhances apigenin-induced apoptosis in human breast cancer cells

    Xuchen Cao; Bowen Liu; Wenfeng Cao; Weiran Zhang; Fei Zhang; Hongmeng Zhao; Ran Meng

    2013-01-01

    Apigenin (4',5,7-trihydroxyflavone) is a member of the flavone subclass of flavonoids present in fruits and vegetables.The involvement of autophagy in the apigenin-induced apoptotic death of human breast cancer cells was investigated.Cell proliferation and viability were assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and clonogenic assays.Flow cytometry,fluorescent staining and Western blot analysis were employed to detect apoptosis and autophagy,and the role of autophagy was assessed using autophagy inhibitors.Apigenin dose-and time-dependently repressed the proliferation and clonogenic survival of the human breast cancer T47D and MDA-MB-231 cell lines.The death of T47D and MDA-MB-231 cells was due to apoptosis associated with increased levels of Caspase3,PARP cleavage and Bax/Bcl-2 ratios.The results from flow cytometry and fluorescent staining also verified the occurrence of apoptosis.In addition,the apigenin-treated cells exhibited autophagy,as characterized by the appearance of autophagosomes under fluorescence microscopy and the accumulation of acidic vesicular organelles (AVOs)by flow cytometry.Furthermore,the results of the Western blot analysis revealed that the level of LC3-Ⅱ,the processed form of LC3-Ⅰ,was increased.Treatment with the autophagy inhibitor,3-methyladenine (3-MA),significantly enhanced the apoptosis induced by apigenin,which was accompanied by an increase in the level of PARP cleavage.Similar results were also confirmed by flow cytometry and fluorescence microscopy.These results indicate that apigenin has apoptosis-and autophagy-inducing effects in breast cancer cells.Autophagy plays a cyto-protective role in apigenin-induced apoptosis,and the combination of apigenin and an autophagy inhibitor may be a promising strategy for breast cancer control.

  14. Determinants of PDT-induced apoptosis

    Kessel, David; Luo, Yu; Kim, Hyeong-Reh C.

    2000-03-01

    Photodynamic therapy can initiate cell death by apoptosis or necrosis. Using agents with known patterns of sub-cellular localization, we examined the correlation between sites of photodamage and the mode of cell death, using murine leukemia cells in vitro. Mitochondrial or mitochondrial/lysosomal photodamage caused the rapid release of cytochrome c. This effect was not temperature sensitive, and could be demonstrated immediately after irradiation of photosensitized cells at 10 degrees C. Subsequent warming to 37 degrees C led to a rapid apoptotic response, consistent with the known ability of cytochrome c to trigger the activation of caspase-3. In contrast, lysosomal or lysosomal/membrane photodamage resulted in the release of cathepsins and other proteolytic enzymes. A subsequent incubation at 37 degrees C resulted in mitochondrial degradation, leading to loss of cytochrome c within 30 min. The apoptotic response was both delayed and incomplete, with many dead cells not exhibiting an apoptotic morphology. The latter outcome was traced to photodamage to procaspase-3, an effect not observed with sensitizers that caused mainly mitochondrial photodamage. Studies in a cell-free system demonstrated that agents with lysosomal and/or membrane targets could bring about photoinactivation of caspase-3. These result are consistent with the proposal that photodynamic therapy can both activate and inactivate components of the apoptotic process.

  15. Intense exercise can cause excessive apoptosis and synapse plasticity damage in rat hippocampus through Ca2+ overload and endoplasmic reticulum stress-induced apoptosis pathway

    Ding Yi; Chang Cunqing; Xie Lan; Chen Zhimin; Ai Hua

    2014-01-01

    Background Intense exercise can cause injury and apoptosis,but few studies have reported its effect on the central nervous system (CNS).The initial reason for hippocampus injury is the excitotoxicity of glutamate and calcium overload.Intracellular free Ca2+ ([Ca2+]i) overload may trigger the apoptosis pathway and neuron damage.The aim of this study was to investigate whether intense exercise could cause hippocampus apoptosis and neuron damage and then to determine which pathway was activated by this apoptosis.Methods We used one bout of swimming exhaustion rats as models.Intracellular [Ca2+]i was measured to estimate the calcium overload by Fura-2/AM immediately after exhaustion; glial fibrillary acidic protein (GFAP) and synaptophysin (SYP)immunofluorescence were performed for estimating astrocyte activation and synapse plasticity 24 hours after exhaustion.Apoptosis cells were displayed using dUTP nick end labelling (TUNEL) stain; endoplasmic reticulum (ER) stress-induced apoptosis pathway and mitochondrial apoptosis pathway were synchronously detected by Western blotting.Results An increasing level of intracellular [Ca2+]i (P <0.01) was found in the hippocampus immediately after exhaustion.GFAP and SYP immunofluorescence showed that the astrocytes are activated,and the synapse plasticity collapsed significantly 24 hours after exhaustion.TUNEL stain showed that the number of apoptosis cells were notably raised (P <0.01); Western blotting of the apoptosis pathway showed increasing levels of caspase-3 cleavage (P <0.01),Bax (P <0.01),caspase-12 cleavage (P <0.01),C/EBP-homologous protein (CHOP) (P <0.01),and phospho-Junaminoterminal kinases (p-JNK; P <0.01) and decreasing level of Bcl-2 (P <0.01).Our results proved that exhaustion can induce hippocampus injury and apoptosis by [Ca2+]i overload,with collapsed synaptic plasticity as the injury pattern and ER stress-induced apoptosis as the activated pathway.Conclusion Intense exercise can cause

  16. Blockade of store-operated calcium entry alleviates ethanol-induced hepatotoxicity via inhibiting apoptosis

    Extracellular Ca2+ influx has been suggested to play a role in ethanol-induced hepatocyte apoptosis and necrosis. Previous studies indicated that store-operated Ca2+ entry (SOCE) was involved in liver injury induced by ethanol in HepG2 cells. However, the mechanisms underlying liver injury caused by SOCE remain unclear. We aimed to investigate the effects and mechanism of SOCE inhibition on liver injury induced by ethanol in BRL cells and Sprague–Dawley rats. Our data demonstrated that ethanol (0–400 mM) dose-dependently increased hepatocyte injury and 100 mM ethanol significantly upregulated the mRNA and protein expression of SOC for at least 72 h in BRL cells. Blockade of SOCE by pharmacological inhibitors and sh-RNA knockdown of STIM1 and Orai1 attenuated intracellular Ca2+ overload, restored the mitochondrial membrane potential (MMP), decreased cytochrome C release and inhibited ethanol-induced apoptosis. STIM1 and Orai1 expression was greater in ethanol-treated than control rats, and the SOCE inhibitor corosolic acid ameliorated the histopathological findings and alanine transaminase and aspartate transaminase activity as well as decreased cytochrome C release and inhibited alcohol-induced cell apoptosis. These findings suggest that SOCE blockade could alleviate alcohol-induced hepatotoxicity via inhibiting apoptosis. SOCE might be a useful therapeutic target in alcoholic liver diseases. - Highlights: • Blockade of SOCE alleviated overload of Ca2+ and hepatotoxicity after ethanol application. • Blockade of SOCE inhibited mitochondrial apoptosis after ethanol application. • SOCE might be a useful therapeutic target in alcoholic liver diseases

  17. Blockade of store-operated calcium entry alleviates ethanol-induced hepatotoxicity via inhibiting apoptosis

    Cui, Ruibing [Department of Hepatology and Gastroenterology, Qilu Hospital of Shandong University, Jinan, Shandong Province 250012 (China); Yan, Lihui [Shandong Normal University, Jinan, Shandong Province 250012 (China); Luo, Zheng; Guo, Xiaolan [Department of Hepatology and Gastroenterology, Qilu Hospital of Shandong University, Jinan, Shandong Province 250012 (China); Yan, Ming, E-mail: ymylh@163.com [Department of Hepatology and Gastroenterology, Qilu Hospital of Shandong University, Jinan, Shandong Province 250012 (China)

    2015-08-15

    Extracellular Ca{sup 2+} influx has been suggested to play a role in ethanol-induced hepatocyte apoptosis and necrosis. Previous studies indicated that store-operated Ca{sup 2+} entry (SOCE) was involved in liver injury induced by ethanol in HepG2 cells. However, the mechanisms underlying liver injury caused by SOCE remain unclear. We aimed to investigate the effects and mechanism of SOCE inhibition on liver injury induced by ethanol in BRL cells and Sprague–Dawley rats. Our data demonstrated that ethanol (0–400 mM) dose-dependently increased hepatocyte injury and 100 mM ethanol significantly upregulated the mRNA and protein expression of SOC for at least 72 h in BRL cells. Blockade of SOCE by pharmacological inhibitors and sh-RNA knockdown of STIM1 and Orai1 attenuated intracellular Ca{sup 2+} overload, restored the mitochondrial membrane potential (MMP), decreased cytochrome C release and inhibited ethanol-induced apoptosis. STIM1 and Orai1 expression was greater in ethanol-treated than control rats, and the SOCE inhibitor corosolic acid ameliorated the histopathological findings and alanine transaminase and aspartate transaminase activity as well as decreased cytochrome C release and inhibited alcohol-induced cell apoptosis. These findings suggest that SOCE blockade could alleviate alcohol-induced hepatotoxicity via inhibiting apoptosis. SOCE might be a useful therapeutic target in alcoholic liver diseases. - Highlights: • Blockade of SOCE alleviated overload of Ca{sup 2+} and hepatotoxicity after ethanol application. • Blockade of SOCE inhibited mitochondrial apoptosis after ethanol application. • SOCE might be a useful therapeutic target in alcoholic liver diseases.

  18. Sphingosine-1 phosphate prevents ethanol-induced corneal epithelial apoptosis

    Pierre Fournie

    2012-01-01

    Full Text Available Background: Apoptosis is a programmed cell death in multicellular organisms, found in a wide variety of conditions, including inflammatory process, everywhere in the body, including the cornea and conjunctiva. Aim: To evaluate the effect of a new topical formulation of sphingosine-1 phosphate on preventing apoptosis of the corneal epithelium. Setting: Medical University. Materials and Methods: We tested several formulations suitable for topical application. Twenty-five rabbits were distributed among five groups. Group 1 comprised the controls. In Group 2, 20% ethanol was applied topically for 20 seconds; in Group 3, 50 μM topical sphingosine-1 phosphate was applied 2 hours prior to 20% ethanol application. In Group 4, 200 μM topical sphingosine-1 phosphate was applied 2 hours before the 20% ethanol application. In Group 5, only 200 μM topical sphingosine-1 phosphate was applied. Apoptosis was evaluated using the terminal deoxynucleotidyl transferase biotin-dUTP Nick End Labeling (TUNEL assay. Pairwise comparisons were performed using t-tests with Scheffe′s correction. Data were analyzed using STATA 9.0 statistical software. Results: A suspension of sphingosine-1 phosphate in the presence of Montanox 80 was stable and could be formulated without sonication. Epithelial apoptosis was detected only in Groups 2 and 3. Conclusion: Sphingosine-1 phosphate can prevent ethanol-induced apoptosis in the corneal epithelium of rabbits.

  19. Electronegative low density lipoprotein induces renal apoptosis and fibrosis: STRA6 signaling involved.

    Chen, Chao-Hung; Ke, Liang-Yin; Chan, Hua-Chen; Lee, An-Sheng; Lin, Kun-Der; Chu, Chih-Sheng; Lee, Mei-Yueh; Hsiao, Pi-Jung; Hsu, Chin; Chen, Chu-Huang; Shin, Shyi-Jang

    2016-08-01

    Dyslipidemia has been proven to capably develop and aggravate chronic kidney disease. We also report that electronegative LDL (L5) is the most atherogenic LDL. On the other hand, retinoic acid (RA) and RA receptor (RAR) agonist are reported to be beneficial in some kidney diseases. "Stimulated by retinoic acid 6" (STRA6), one retinol-binding protein 4 receptor, was recently identified to regulate retinoid homeostasis. Here, we observed that L5 suppressed STRA6 cascades [STRA6, cellular retinol-binding protein 1 (CRBP1), RARs, retinoid X receptor α, and retinol, RA], but L5 simultaneously induced apoptosis and fibrosis (TGFβ1, Smad2, collagen 1, hydroxyproline, and trichrome) in kidneys of L5-injected mice and L5-treated renal tubular cells. These L5-induced changes of STRA6 cascades, renal apoptosis, and fibrosis were reversed in kidneys of LOX1(-/-) mice. LOX1 RNA silencing and inhibitor of c-Jun N-terminal kinase and p38MAPK rescued the suppression of STRA6 cascades and apoptosis and fibrosis in L5-treated renal tubular cells. Furthermore, crbp1 gene transfection reversed downregulation of STRA6 cascades, apoptosis, and fibrosis in L5-treated renal tubular cells. For mimicking STRA6 deficiency, efficient silencing of STRA6 RNA was performed and was found to repress STRA6 cascades and caused apoptosis and fibrosis in L1-treated renal tubular cells. In summary, this study reveals that electronegative L5 can cause kidney apoptosis and fibrosis via the suppression of STRA6 cascades, and implicates that STRA6 signaling may be involved in dyslipidemia-mediated kidney disease. PMID:27256691

  20. Role of apoptosis-inducing factor, proline dehydrogenase, and NADPH oxidase in apoptosis and oxidative stress

    Becker DF

    2012-02-01

    Full Text Available Sathish Kumar Natarajan, Donald F BeckerDepartment of Biochemistry and Redox Biology Center, University of Nebraska-Lincoln, Lincoln, NEAbstract: Flavoproteins catalyze a variety of reactions utilizing flavin mononucleotide or flavin adenine dinucleotide as cofactors. The oxidoreductase properties of flavoenzymes implicate them in redox homeostasis, oxidative stress, and various cellular processes, including programmed cell death. Here we explore three critical flavoproteins involved in apoptosis and redox signaling, ie, apoptosis-inducing factor (AIF, proline dehydrogenase, and NADPH oxidase. These proteins have diverse biochemical functions and influence apoptotic signaling by unique mechanisms. The role of AIF in apoptotic signaling is two-fold, with AIF changing intracellular location from the inner mitochondrial membrane space to the nucleus upon exposure of cells to apoptotic stimuli. In the mitochondria, AIF enhances mitochondrial bioenergetics and complex I activity/assembly to help maintain proper cellular redox homeostasis. After translocating to the nucleus, AIF forms a chromatin degrading complex with other proteins, such as cyclophilin A. AIF translocation from the mitochondria to the nucleus is triggered by oxidative stress, implicating AIF as a mitochondrial redox sensor. Proline dehydrogenase is a membrane-associated flavoenzyme in the mitochondrion that catalyzes the rate-limiting step of proline oxidation. Upregulation of proline dehydrogenase by the tumor suppressor, p53, leads to enhanced mitochondrial reactive oxygen species that induce the intrinsic apoptotic pathway. NADPH oxidases are a group of enzymes that generate reactive oxygen species for oxidative stress and signaling purposes. Upon activation, NADPH oxidase 2 generates a burst of superoxide in neutrophils that leads to killing of microbes during phagocytosis. NADPH oxidases also participate in redox signaling that involves hydrogen peroxide-mediated activation of

  1. Glycyrrhetinic acid-induced permeability transition in rat liver mitochondria.

    Salvi, Mauro; Fiore, Cristina; Armanini, Decio; Toninello, Antonio

    2003-12-15

    Glycyrrhetinic acid, a hydrolysis product of one of the main constituents of licorice, the triterpene glycoside of glycyrrhizic acid, when added to rat liver mitochondria at micromolar concentrations induces swelling, loss of membrane potential, pyridine nucleotide oxidation, and release of cytochrome c and apoptosis inducing factor. These changes are Ca(2+) dependent and are prevented by cyclosporin A, bongkrekic acid, and N-ethylmaleimide. All these observations indicate that glycyrrhetinic acid is a potent inducer of mitochondrial permeability transition and can trigger the pro-apoptotic pathway. PMID:14637195

  2. Nuclear apoptosis induced by isolated mitochondria

    2000-01-01

    We isolated and purified mitochondria from mouse livers and spinach leaves. When added into egg extracts of Xenopus laevis, they caused nuclei of mouse liver to undergo apoptotic changes. Chromatin condensation, margination and DNA ladder were observed. After incubating isolated mitochondria in some hypotonic solutions, and centrifuging these mixtures at high speed, we got mitochondrial supernatants. It was found that in the absence of cytosolic factor, the supernatant alone was able to induce apoptotic changes in nuclei. The effective components were partly of protein. DNA fragmentation was partly inhibited by caspase inhibitors AC-DEVD-CHO and AC-YVADCHO. Meanwhile, caspase inhibitors fully blocked chromatin condensation. Primary characterization of the nuclear endonuclease(s) induced by mitochondrial supernatants was also conducted. It was found that this endonuclease is different from endonuclease G, cytochrome c-induced nuclease, or Ca2+-activated endonuclease.

  3. The Non-structural Protein of Crimean-Congo Hemorrhagic Fever Virus Disrupts the Mitochondrial Membrane Potential and Induces Apoptosis.

    Barnwal, Bhaskar; Karlberg, Helen; Mirazimi, Ali; Tan, Yee-Joo

    2016-01-01

    Viruses have developed distinct strategies to overcome the host defense system. Regulation of apoptosis in response to viral infection is important for virus survival and dissemination. Like other viruses, Crimean-Congo hemorrhagic fever virus (CCHFV) is known to regulate apoptosis. This study, for the first time, suggests that the non-structural protein NSs of CCHFV, a member of the genus Nairovirus, induces apoptosis. In this report, we demonstrated the expression of CCHFV NSs, which contains 150 amino acid residues, in CCHFV-infected cells. CCHFV NSs undergoes active degradation during infection. We further demonstrated that ectopic expression of CCHFV NSs induces apoptosis, as reflected by caspase-3/7 activity and cleaved poly(ADP-ribose) polymerase, in different cell lines that support CCHFV replication. Using specific inhibitors, we showed that CCHFV NSs induces apoptosis via both intrinsic and extrinsic pathways. The minimal active region of the CCHFV NSs protein was determined to be 93-140 amino acid residues. Using alanine scanning, we demonstrated that Leu-127 and Leu-135 are the key residues for NSs-induced apoptosis. Interestingly, CCHFV NSs co-localizes in mitochondria and also disrupts the mitochondrial membrane potential. We also demonstrated that Leu-127 and Leu-135 are important residues for disruption of the mitochondrial membrane potential by NSs. Therefore, these results indicate that the C terminus of CCHFV NSs triggers mitochondrial membrane permeabilization, leading to activation of caspases, which, ultimately, leads to apoptosis. Given that multiple factors contribute to apoptosis during CCHFV infection, further studies are needed to define the involvement of CCHFV NSs in regulating apoptosis in infected cells. PMID:26574543

  4. Herbal medicine as inducers of apoptosis in cancer treatment.

    Safarzadeh, Elham; Sandoghchian Shotorbani, Siamak; Baradaran, Behzad

    2014-10-01

    Cancer is uncontrolled growth of abnormal cells in the body. Nowadays, cancer is considered as a human tragedy and one of the most prevalent diseases in the wide, and its mortality resulting from cancer is being increased. It seems necessary to identify new strategies to prevent and treat such a deadly disease. Control survival and death of cancerous cell are important strategies in the management and therapy of cancer. Anticancer agents should kill the cancerous cell with the minimal side effect on normal cells that is possible through the induction of apoptosis. Apoptosis is known as programmed cell death in both normal and damaged tissues. This process includes some morphologically changes in cells such as rapid condensation and budding of the cell, formation of membrane-enclosed apoptotic bodies with well-preserved organelles. Induction of apoptosis is one of the most important markers of cytotoxic antitumor agents. Some natural compounds including plants induce apoptotic pathways that are blocked in cancer cells through various mechanisms in cancer cells. Multiple surveys reported that people with cancer commonly use herbs or herbal products. Vinca Alkaloids, Texans, podo phyllotoxin, Camptothecins have been clinically used as Plant derived anticancer agents. The present review summarizes the literature published so far regarding herbal medicine used as inducers of apoptosis in cancer. PMID:25364657

  5. Herbal Medicine as Inducers of Apoptosis in Cancer Treatment

    Elham Safarzadeh

    2014-12-01

    Full Text Available Cancer is uncontrolled growth of abnormal cells in the body. Nowadays, cancer is considered as a human tragedy and one of the most prevalent diseases in the wide, and its mortality resulting from cancer is being increased. It seems necessary to identify new strategies to prevent and treat such a deadly disease. Control survival and death of cancerous cell are important strategies in the management and therapy of cancer. Anticancer agents should kill the cancerous cell with the minimal side effect on normal cells that is possible through the induction of apoptosis. Apoptosis is known as programmed cell death in both normal and damaged tissues. This process includes some morphologically changes in cells such as rapid condensation and budding of the cell, formation of membrane-enclosed apoptotic bodies with well-preserved organelles. Induction of apoptosis is one of the most important markers of cytotoxic antitumor agents. Some natural compounds including plants induce apoptotic pathways that are blocked in cancer cells through various mechanisms in cancer cells. Multiple surveys reported that people with cancer commonly use herbs or herbal products. Vinca Alkaloids, Texans, podo phyllotoxin, Camptothecins have been clinically used as Plant derived anticancer agents. The present review summarizes the literature published so far regarding herbal medicine used as inducers of apoptosis in cancer.

  6. Infrasound sensitizes human glioblastoma cells to cisplatin-induced apoptosis.

    Rachlin, Kenneth; Moore, Dan H; Yount, Garret

    2013-11-01

    The development of nontoxic agents that can selectively enhance the cytotoxicity of chemotherapy is an important aim in oncology. This study evaluates the ability of infrasound exposure to sensitize glioblastoma cells to cisplatin-induced apoptosis. The infrasound was delivered using a device designed to replicate the unique infrasound emissions measured during external Qigong treatments. Human glioblastoma cell lines harboring wild-type p53 (U87) or mutant p53 (U251, SF210, and SF188) were treated in culture with cisplatin, infrasound emissions, or the combination of the 2 agents. Induction of apoptosis was quantified after 24 hours by flow cytometry following annexin V/propidium iodide staining. Infrasound emissions alone, delivered at moderate levels (~10 mPa) with dynamic frequency content (7-13 Hz), did not induce apoptosis, yet combining infrasound with cisplatin augmented the induction of apoptosis by cisplatin in all the 4 cell lines (P infrasound exposure was quantified by fluorescence microscopy as well as flow cytometry, demonstrating increased cell membrane permeability. The 4 cell lines differed in the degree to which infrasound exposure increased calcein uptake, and these differences were predictive of the extent to which infrasound enhanced cisplatin-induced apoptosis. When exposed to specific frequencies, membrane permeabilization also appeared to be differentially responsive for each cell line, suggesting the potential for selective targeting of tissue types using isolated infrasonic frequencies. Additionally, the pressure amplitudes used in this study were several orders of magnitude less than those used in similar studies involving ultrasound and shock waves. The results of this study provide support for using infrasound to enhance the chemotherapeutic effects of cisplatin in a clinical setting. PMID:23165942

  7. A novel approach to enhancing ganoderic acid production by Ganoderma lucidum using apoptosis induction.

    Bang-Jau You

    Full Text Available Ganoderma lucidum is one of most widely used herbal medicine and functional food in Asia, and ganoderic acids (GAs are its active ingredients. Regulation of GA biosynthesis and enhancing GA production are critical to using G. lucidum as a medicine. However, regulation of GA biosynthesis by various signaling remains poorly understood. This study investigated the role of apoptosis signaling on GA biosynthesis and presented a novel approach, namely apoptosis induction, to increasing GA production. Aspirin was able to induce cell apoptosis in G. lucidum, which was identified by terminal deoxynucleotidyl transferase mediated dUPT nick end labeling assay positive staining and a condensed nuclear morphology. The maximum induction of lanosta-7,9(11, 24-trien-3α-01-26-oic acid (ganoderic acid 24, GA24 production and total GA production by aspirin were 2.7-fold and 2.8-fold, respectively, after 1 day. Significantly lower levels of GA 24 and total GAs were obtained after regular fungal culture for 1.5 months. ROS accumulation and phosphorylation of Hog-1 kinase, a putative homolog of MAPK p38 in mammals, occurred after aspirin treatment indicating that both factors may be involved in GA biosynthetic regulation. However, aspirin also reduced expression of the squalene synthase and lanosterol synthase coding genes, suggesting that these genes are not critical for GA induction. To the best of our knowledge, this is the first report showing that GA biosynthesis is linked to fungal apoptosis and provides a new approach to enhancing secondary metabolite production in fungi.

  8. Parvovirus B19-Induced Apoptosis of Hepatocytes

    Poole, Brian D.; Karetnyi, Yuory V.; Naides, Stanley J.

    2004-01-01

    Parvovirus B19 (B19 virus) can persist in multiple tissues and has been implicated in a variety of diseases, including acute fulminant liver failure. The mechanism by which B19 virus induces liver failure remains unknown. Hepatocytes are nonpermissive for B19 virus replication. We previously reported that acute fulminant liver failure associated with B19 virus infection was characterized by hepatocellular dropout. We inoculated both primary hepatocytes and the hepatocellular carcinoma cell li...

  9. Cyclic GMP protects human macrophages against peroxynitrite-induced apoptosis

    Rossi Adriano G

    2009-05-01

    Full Text Available Abstract Background Nitric oxide (NO can be both pro- and anti-apoptotic in various cell types, including macrophages. This apparent paradox may result from the actions of NO-related species generated in the microenvironment of the cell, for example the formation of peroxynitrite (ONOO-. In this study we have examined the ability of NO and ONOO- to evoke apoptosis in human monocyte-derived macrophages (MDMϕ, and investigated whether preconditioning by cyclic guanosine monophosphate (cGMP is able to limit apoptosis in this cell type. Methods Characterisation of the NO-related species generated by (Z-1- [2-(2-aminoethyl-N-(2-ammonioethylamino]diazen-1-ium-1,2-diolate (DETA/NO and 1,2,3,4-oxatriazolium, 5-amino-3-(3,4-dichlorophenyl-, chloride (GEA-3162 was performed by electrochemistry using an isolated NO electrode and electron paramagnetic resonance (EPR spectrometry. Mononuclear cells were isolated from peripheral blood of healthy volunteers and cultured to allow differentiation into MDMϕ. Resultant MDMϕ were treated for 24 h with DETA/NO (100 – 1000 μM or GEA-3162 (10 – 300 μM in the presence or absence of BAY 41–2272 (1 μM, isobutylmethylxanthine (IBMX; 1 μM, 1H- [1,2,4]oxadiazolo [4,3-a]quinoxalin-1-one (ODQ; 20 μM or 8-bromo-cGMP (1 mM. Apoptosis in MDMϕ was assessed by flow cytometric analysis of annexin V binding in combination with propidium iodide staining. Results Electrochemistry and EPR revealed that DETA/NO liberated free NO radical, whilst GEA-3162 concomitantly released NO and O2-, and is therefore a ONOO- generator. NO (DETA/NO had no effect on cell viability, but ONOO- (GEA-3162 caused a concentration-dependent induction of apoptosis in MDMϕ. Preconditioning of MDMϕ with NO in combination with the phosphodiesterase inhibitor, 3-Isobutyl-1-methylxanthine (IBMX, or the NO-independent stimulator of soluble guanylate cyclase, BAY 41–2272, significantly attenuated ONOO--induced apoptosis in a cGMP-dependent manner

  10. Pulse mode of laser photodynamic treatment induced cell apoptosis.

    Klimenko, Vladimir V; Knyazev, Nickolay A; Moiseenko, Fedor V; Rusanov, Anatoliy A; Bogdanov, Alexey A; Dubina, Michael V

    2016-03-01

    One of the factors limiting photodynamic therapy (PDT) is hypoxia in tumor cells during photodynamic action. PDT with pulse mode irradiation and appropriate irradiation parameters could be more effective in the singlet oxygen generation and tissue re-oxygenation than continuous wave (CW) mode. We theoretically demonstrate differences between the cumulative singlet oxygen concentration in PDT using pulse mode and CW mode of laser irradiation. In vitro experimental results show that photodynamic treatment with pulse mode irradiation has similar cytotoxicity to CW mode and induces mainly cell apoptosis, whereas CW mode induces necrotic cell death. We assume that the cumulative singlet oxygen concentration and the temporal distribution of singlet oxygen are important in photodynamic cytotoxicity and apoptosis initiation. We expect our research may improve irradiation protocols and photodynamic therapy efficiency. PMID:26790610

  11. Neem oil limonoids induces p53-independent apoptosis and autophagy

    Srivastava, Pragya; Yadav, Neelu; Lella, Ravi; Schneider, Andrea; Jones, Anthony; Marlowe, Timothy; Lovett, Gabrielle; O’Loughlin, Kieran; Minderman, Hans; Gogada, Raghu; Chandra, Dhyan

    2012-01-01

    Azadirachta indica, commonly known as neem, has a wide range of medicinal properties. Neem extracts and its purified products have been examined for induction of apoptosis in multiple cancer cell types; however, its underlying mechanisms remain undefined. We show that neem oil (i.e., neem), which contains majority of neem limonoids including azadirachtin, induced apoptotic and autophagic cell death. Gene silencing demonstrated that caspase cascade was initiated by the activation of caspase-9,...

  12. Resveratrol Induces Glioma Cell Apoptosis through Activation of Tristetraprolin

    Ryu, Jinhyun; Yoon, Nal Ae; Seong, Hyemin; Jeong, Joo Yeon; Kang, Seokmin; Park, Nammi; Choi, Jungil; Lee, Dong Hoon; Roh, Gu Seob; Kim, Hyun Joon; Cho, Gyeong Jae; Choi, Wan Sung; Park, Jae-Yong; Park, Jeong Woo; Kang, Sang Soo

    2015-01-01

    Tristetraprolin (TTP) is an AU-rich elements (AREs)-binding protein, which regulates the decay of AREs-containing mRNAs such as proto-oncogenes, anti-apoptotic genes and immune regulatory genes. Despite the low expression of TTP in various human cancers, the mechanism involving suppressed expression of TTP is not fully understood. Here, we demonstrate that Resveratrol (3,5,4′-trihydroxystilbene, Res), a naturally occurring compound, induces glioma cell apoptosis through activation of tristetr...

  13. Radiation-induced apoptosis in microvascular endothelial cells.

    Langley, R. E.; Bump, E A; Quartuccio, S. G.; Medeiros, D.; Braunhut, S. J.

    1997-01-01

    The response of the microvasculature to ionizing radiation is thought to be an important factor in the overall response of both normal tissues and tumours. It has recently been reported that basic fibroblast growth factor (bFGF), a potent mitogen for endothelial cells, protects large vessel endothelial cells from radiation-induced apoptosis in vitro. Microvessel cells are phenotypically distinct from large vessel cells. We studied the apoptotic response of confluent monolayers of capillary en...

  14. Salinomycin simultaneously induces apoptosis and autophagy through generation of reactive oxygen species in osteosarcoma U2OS cells.

    Kim, Sang-Hun; Choi, Young-Jun; Kim, Kwang-Youn; Yu, Sun-Nyoung; Seo, Young-Kyo; Chun, Sung-Sik; Noh, Kyung-Tae; Suh, Jeung-Tak; Ahn, Soon-Cheol

    2016-04-29

    Salinomycin, a polyether antibiotic, acts as a highly selective potassium ionophore. It was reported to anticancer activity on various cancer cell lines. In this study, salinomycin was examined on apoptosis and autophagy through generation of reactive oxygen species (ROS) in osteosarcoma U2OS cells. Apoptosis, autophagy, mitochondrial membrane potential (MMP) and ROS were analyzed using flow cytometry. Also, expressions of apoptosis- and autophagy-related proteins were determined by western blotting. As a result, salinomycin triggered apoptosis of U2OS cells, which was accompanied by change of MMP and cleavage of caspases-3 and poly (ADP-ribose) polymerase. And salinomycin increased the expression of autophagy-related protein and accumulation of acidic vesicular organelles (AVO). Salinomycin-induced ROS production promotes both apoptosis and autophagy, as evidenced by the result that treatment of N-acetyl-l-cysteine (NAC), a ROS scavenger, attenuated both apoptosis and autophagy. In addition, inhibition of autophagy by 3-methyladenine (3 MA) enhanced the salinoymcin-induced apoptosis. Taken together, these results suggested that salinomycin-induced autophagy, as a survival mechanism, might be a potential strategy through ROS regulation in cancer therapy. PMID:27033598

  15. High glucose augments stress-induced apoptosis in endothelial cells

    Wenwen Zhong; Yang Liu; Hui Tian

    2009-01-01

    Hyperglycemia has been identified as one of the important factors involved in the microvascular complications of diabetes, and has been related to increased cardiovascular mortality. Endothelial damage and dysfunction result from diabetes; therefore, the aim of this study was to determine the response of endothelial cells to stressful stimuli, modelled in normal and high glucose concentrations in vitro. Eahy 926 endothelial cells were cultured in 5 mmol/L or 30 mmol/L glucose conditions for a 24 hour period and oxidative stress was induced by exposure to hydrogen peroxide (H2O2) or tumour necrosis factor- α (TNF- α ), following which the protective effect of the glucocorticoid dexamethasone was assessed. Apoptosis, necrosis and cell viability were determined using an ELISA for DNA fragmentation, an enzymatic lactate dehydrogenase assay and an MTT assay, respectively. High glucose significantly increased the susceptibility of Eahy 926 cells to apoptosis in the presence of 500 μmol/L H2O2, above that induced in normal glucose (P<0.02). A reduction of H2O2- and TNF- α -induced apoptosis occurred in both high and low glucose after treatment with dexametha-sone (P<0.05). Conclusion high glucose is effective in significantly augmenting stress caused by H2O2, but not in causing stress alone. These findings suggest a mechanism by which short term hyperglycemia may facilitate and augment endothelial damage.

  16. Sangivamycin induces apoptosis by suppressing Erk signaling in primary effusion lymphoma cells

    Highlights: • Sangivamycin induces the apoptosis of B cell lymphoma PEL cells. • Sangivamycin suppresses Erk signaling by inhibiting Erk phosphorylation in PEL cells. • The activation of Erk signaling is essential for PEL cell survival. • Sangivamycin induces the apoptosis of PEL cells without production of progeny virus. • Sangivamycin may serve as a novel drug for the treatment of PEL. - Abstract: Sangivamycin, a structural analog of adenosine and antibiotic exhibiting antitumor and antivirus activities, inhibits protein kinase C and the synthesis of both DNA and RNA. Primary effusion lymphoma (PEL) is an aggressive neoplasm caused by Kaposi’s sarcoma-associated herpesvirus (KSHV) in immunosuppressed patients and HIV-infected homosexual males. PEL cells are derived from post-germinal center B cells, and are infected with KSHV. Herein, we asked if sangivamycin might be useful to treat PEL. We found that sangivamycin killed PEL cells, and we explored the underlying mechanism. Sangivamycin treatment drastically decreased the viability of PEL cell lines compared to KSHV-uninfected B lymphoma cell lines. Sangivamycin induced the apoptosis of PEL cells by activating caspase-7 and -9. Further, sangivamycin suppressed the phosphorylation of Erk1/2 and Akt, thus inhibiting activation of the proteins. Inhibitors of Akt and MEK suppressed the proliferation of PEL cells compared to KSHV-uninfected cells. It is known that activation of Erk and Akt signaling inhibits apoptosis and promotes proliferation in PEL cells. Our data therefore suggest that sangivamycin induces apoptosis by inhibiting Erk and Akt signaling in such cells. We next investigated whether sangivamycin, in combination with an HSP90 inhibitor geldanamycin (GA) or valproate (valproic acid), potentiated the cytotoxic effects of the latter drugs on PEL cells. Compared to treatment with GA or valproate alone, the addition of sangivamycin enhanced cytotoxic activity. Our data thus indicate that

  17. Sangivamycin induces apoptosis by suppressing Erk signaling in primary effusion lymphoma cells

    Wakao, Kazufumi [Department of Biotechnology, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Kofu-shi 400-8511 (Japan); Watanabe, Tadashi [Department of Cell Biology, Kyoto Pharmaceutical University, Misasagi-Shichonocho 1, Yamashinaku, Kyoto 607-8412 (Japan); Takadama, Tadatoshi; Ui, Sadaharu [Department of Biotechnology, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Kofu-shi 400-8511 (Japan); Shigemi, Zenpei; Kagawa, Hiroki [Department of Cell Biology, Kyoto Pharmaceutical University, Misasagi-Shichonocho 1, Yamashinaku, Kyoto 607-8412 (Japan); Higashi, Chizuka; Ohga, Rie; Taira, Takahiro [Department of Molecular Cell Biology, Faculty of Medicine, University of Yamanashi, Chuoh-shi 409-3898 (Japan); Fujimuro, Masahiro, E-mail: fuji2@mb.kyoto-phu.ac.jp [Department of Cell Biology, Kyoto Pharmaceutical University, Misasagi-Shichonocho 1, Yamashinaku, Kyoto 607-8412 (Japan)

    2014-02-07

    Highlights: • Sangivamycin induces the apoptosis of B cell lymphoma PEL cells. • Sangivamycin suppresses Erk signaling by inhibiting Erk phosphorylation in PEL cells. • The activation of Erk signaling is essential for PEL cell survival. • Sangivamycin induces the apoptosis of PEL cells without production of progeny virus. • Sangivamycin may serve as a novel drug for the treatment of PEL. - Abstract: Sangivamycin, a structural analog of adenosine and antibiotic exhibiting antitumor and antivirus activities, inhibits protein kinase C and the synthesis of both DNA and RNA. Primary effusion lymphoma (PEL) is an aggressive neoplasm caused by Kaposi’s sarcoma-associated herpesvirus (KSHV) in immunosuppressed patients and HIV-infected homosexual males. PEL cells are derived from post-germinal center B cells, and are infected with KSHV. Herein, we asked if sangivamycin might be useful to treat PEL. We found that sangivamycin killed PEL cells, and we explored the underlying mechanism. Sangivamycin treatment drastically decreased the viability of PEL cell lines compared to KSHV-uninfected B lymphoma cell lines. Sangivamycin induced the apoptosis of PEL cells by activating caspase-7 and -9. Further, sangivamycin suppressed the phosphorylation of Erk1/2 and Akt, thus inhibiting activation of the proteins. Inhibitors of Akt and MEK suppressed the proliferation of PEL cells compared to KSHV-uninfected cells. It is known that activation of Erk and Akt signaling inhibits apoptosis and promotes proliferation in PEL cells. Our data therefore suggest that sangivamycin induces apoptosis by inhibiting Erk and Akt signaling in such cells. We next investigated whether sangivamycin, in combination with an HSP90 inhibitor geldanamycin (GA) or valproate (valproic acid), potentiated the cytotoxic effects of the latter drugs on PEL cells. Compared to treatment with GA or valproate alone, the addition of sangivamycin enhanced cytotoxic activity. Our data thus indicate that

  18. Dracorhodin perchlorate induces the apoptosis of glioma cells.

    Chen, Xin; Luo, Junjie; Meng, Linghu; Pan, Taifeng; Zhao, Binjie; Tang, Zhen-Gang; Dai, Yongjian

    2016-04-01

    Dracorhodin perchlorate (Dp), a synthetic analogue of the antimicrobial anthocyanin red pigment, has recently been shown to induce apoptotic cell death in various types of cancer cells. Yet, the inhibitory effect of Dp on human glioma cells remains uninvestigated. Therefore, in the present study, 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay and flow cytometry were used to detect cell viability and cell cycle progression in glioma U87MG and T98G cells, respectively. Annexin V-FITC/propidium iodide double staining and JC-1 staining were separately applied to determine cellular apoptosis and mitochondrial membrane potential damage in the cells. The expression levels of associated proteins involved in cell cycle progression and apoptosis were measured by western blotting. The activities of caspase‑9/-3 were determined by Caspase-Glo-9/3 assay. The results indicated that Dp treatment significantly inhibited cell proliferation in a dose- and time-dependent manner, and blocked cell cycle progression at the G1/S phase in the U87MG and T98G cells via the upregulation of p53 and p21 protein expression, and simultaneous downregulation of Cdc25A, Cdc2 and P-Cdc2 protein expression. Additionally, Dp treatment led to the loss of cellular mitochondrial membrane potential, and the release of cytochrome c, and strongly induced the occurence of apoptosis. Increased expression levels of Bim and Bax protein and the downregulated expression of Bcl-2 protein were observed. Caspase-9/-3 were activated and their activities were elevated after Dp treatment. These findings indicate that Dp inhibits cell proliferation, induces cell cycle arrest and apoptosis in glioma cells, and is a possible candidate for glioma treatment. PMID:26846469

  19. PUMA and Bax-induced Autophagy Contributes to Apoptosis

    Yee, Karen S.; Wilkinson, Simon; James, John; Ryan, Kevin M.; Vousden, Karen H.

    2009-01-01

    The p53-inducible BH3-only protein PUMA is a key mediator of p53-dependent apoptosis, and PUMA has been shown to function by activating Bax and mitochondrial outer membrane permeabilization. In this study we describe an ability of PUMA to induce autophagy that leads to the selective removal of mitochondria. This function of PUMA depends on Bax/Bak and can be reproduced by overexpression of Bax. The induction of autophagy coincides with cytochrome c release, and taken together the results sugg...

  20. PUMA- and Bax-induced autophagy contributes to apoptosis

    Yee, K S; Wilkinson, S; James, J; Ryan, K M; Vousden, K H

    2009-01-01

    The p53-inducible BH3-only protein PUMA is a key mediator of p53-dependent apoptosis, and PUMA has been shown to function by activating Bax and mitochondrial outer membrane permeabilization. In this study, we describe an ability of PUMA to induce autophagy that leads to the selective removal of mitochondria. This function of PUMA depends on Bax/Bak and can be reproduced by overexpression of Bax. The induction of autophagy coincides with cytochrome c release, and taken together the results sug...

  1. Inhibition of TLR8 mediated signaling promotes BCG induced apoptosis in THP-1 cells.

    Tang, Jun; Zhan, Lingjun; Qin, Chuan

    2016-04-01

    Apoptosis was considered as one of the important host defense mechanisms against mycobacteria infection. In macrophage, the main target cell of Mycobacterium tuberculosis, apoptosis after infection could help kill the bacillus inside and process the antigens for further presentation and proper immune response. Here, we identified a role of TLR8 during the apoptosis induced by Bacillus Calmette Guérin (BCG) infection in THP-1 cells. Knockdown TLR8 further increased the apoptosis induced by BCG infection, and this enhanced apoptosis was caspase-dependent. During this process, Erk1/2, JNK and NFκB pathways were negatively affected and contributed to the enhanced apoptosis. PMID:26657720

  2. The expression of oncogenes on the radiation-induced apoptosis in SCK mammary adenocarcinoma cell line

    The expression of p53, p21/WAF/CIP, Bcl-2, and Bax underlying the radiation-induced apoptosis in different pH environments using SCK mammary adenocarcinoma cell line was investigated. Mammary adenocarcinoma cells of A/J mice (SCK cells) in exponential growth phase were irradiated with a linear accelerator at room temperature. The cells were irradiated with 12 Gy and one hour later, the media was replaced with fresh media at a different pHs. After incubation at 37 .deg. for 0-48 h, the extent of apoptosis was determined using agarose gel electrophoresis and flow cytometry. The progression of cells through the cell cycle after irradiation in different pHs was also determined with flow cytometry. Western blot analysis was used to monitor p53, P21/WAF/CIP, BcI-2, and Bax protein levels. The induction of apoptosis by irradiation in pH 6.6 medium was markedly less than that in pH 7.5 medium. The radiation-induced G2/M arrest in pH 6.6 medium lasted markedly longer than that in pH 7.5 medium. Considerable amounts of p53 and p21 proteins already existed at pH 7.5 and increased the level of p53 and p21 significantly after 12 Gy X-irradiation. An incubation at pH6.6 after 12 Gy X-irradiation did not change the level of p53 and p21 protein levels significantly. BcI-2 proteins were not significantly affected by radiation and showed no correlation with cell susceptibility to radiation-induced apoptosis in different pHs. An exposure to 12 Gy of X-rays increased the level of Bax protein at pH 7.5 but at pH 6.6, it was slight. The molecular mechanism underlying radiation-induced apoptosis in different pH environments using SCK mammary adenocarcinoma cell line was dependent of the expression p53 and p21/WAF/CIP proteins. We may propose following hypothesis that an acidic stress augments the radiation-induced G2/M arrest, which inhibiting the irradiated cells undergo post-mitotic apoptosis. The effects of environmental acidity on anti-apoptotic and pro-apoptotic function of BcI-2

  3. Focused ultrasound induces apoptosis in pancreatic cancer cells

    GUO Qian; JIANG Li-xin; HU Bing

    2012-01-01

    Background The incidence and mortality rate of pancreatic cancer have increased dramatically in China over recent decades.Focused ultrasound (FU) has been somewhat successful in treating pancreatic cancer.The purpose of this study was to investigate apoptosis in pancreatic cancer cells induced by FU.Methods Suspension of human pancreatic carcinoma cell line PaTu 8988t was radiated by FU,using five doses with different radiation parameters and patterns,including one blank control.Temperature increase of the cell suspension was monitored.Cell apoptosis and death after FU radiation was observed using fluorescence microscopy and was tested by flow cytometer at 3,6,12,24,and 48 hours after ultrasound radiation.Results The maximum cell suspension temperatures following five radiation doses were 28°C,(42.20±2.17)°C,(50.80±0.84)°C,(55.80±2.17)°C,and (65.20±3.11)°C; differences between the doses were statistically significant (P <0.05).The apoptosis rate peaked at 24 hours after radiation,at (0.56±0.15)%,(1.28±0.16)%,(1.84±0.29)%,(5.74±1.15)%,and (2.00±0.84)% for the five doses; differences between the doses were statistically significant (P <0.05).Between doses 1-4,cell apoptosis rates increased as the Tmax increased.In dose 5,as the Tmax was above 60°C,the apoptosis rate decreased.Conclusion Sub-threshold thermal exposures of FU radiation with a continuous radiation pattern could result in higher oercentage of apoptosed cells.

  4. PUMA mediates ER stress-induced apoptosis in portal hypertensive gastropathy

    Tan, S.; Wei, X; Song, M; Tao, J.; Yang, Y; Khatoon, S.; Liu, H.; J. Jiang; Wu, B

    2014-01-01

    Mucosal apoptosis has been demonstrated to be an essential pathological feature in portal hypertensive gastropathy (PHG). p53-upregulated modulator of apoptosis (PUMA) was identified as a BH3-only Bcl-2 family protein that has an essential role in apoptosis induced by a variety of stimuli, including endoplasmic reticulum (ER) stress. However, whether PUMA is involved in mucosal apoptosis in PHG remains unclear, and whether PUMA induces PHG by mediating ER stress remains unknown. The aim of th...

  5. Aging might increase myocardial ischemia / reperfusion-induced apoptosis in humans and rats

    Liu, Miaobing; Zhang, Ping; Chen, Mulei; Zhang, Wuning; Yu, Liping; Yang, Xin-Chun; Fan, Qian

    2011-01-01

    Previous studies indicated aging results in the significant cardiac function decreasing and myocardial apoptosis increasing in normal humans or rats. Additionally, animal experiments demonstrated aging increased myocardial ischemia / reperfusion (MI/R)-induced apoptosis. However, whether more myocardial apoptosis happen in the old acute myocardial infarction (AMI) patients is unclear. Reperfusion injury-induced apoptosis is an important cause of heart failure. This study determined the effect...

  6. Apoptosis induced by granzyme B-glycosaminoglycan complexes: implications for granule-mediated apoptosis in vivo.

    Galvin, J P; Spaeny-Dekking, L H; Wang, B; Seth, P; Hack, C E; Froelich, C J

    1999-05-01

    Lymphocyte granule-mediated apoptosis occurs by perforin-mediated intracellular delivery of granule-associated serine proteases (granzymes). A granule-associated proteoglycan, namely serglycin, that contains chondroitin 4-sulfate (CS) glycosaminoglycans is present in the granules of cytotoxic cells. Serglycin acts as scaffold for packaging the positively charged granzymes and probably chaperones the proteases secreted extracellularly. To learn how the interaction of granzyme B (GrB) with serglycin might influence the apoptotic potential of this proteases, we have evaluated a model system where desalted CS is combined with isolated human granzyme. CS-GrB complexes were very stable, remaining undissociated in salt concentrations upwards to 500 mM (pH 7.4). On the basis of a capture enzyme immunoassay that accurately detects GrB, equivalent amounts of active free and CS-GrB, delivered by perforin or adenovirus, efficiently induced apoptosis in Jurkat cells and produced a similar time-dependent increase in caspase-3-like activity. CS-GrB processed isolated caspases-3 and -7 less efficiently than free granzyme. However, when added to cytosolic extracts, rates of processing were nearly equivalent for the two forms, suggesting cationic GrB may nonspecifically bind cytosolic proteins, leading to reduce proteolytic activity. Finally, GrB was found to be exocytosed from lymphocyte-activated killer cells as a neutral, high macromolecular weight complex, which possessed apoptotic activity. Collectively, the results indicate that neutral, high m.w. GrB has the capacity to induce cell death and will be useful to study the mechanism of cytotoxic cell-mediated apoptosis in vitro. PMID:10228010

  7. Roscovitine ameliorates endotoxin-induced uveitis through neutrophil apoptosis.

    Jiang, Zhao-Xin; Qiu, Suo; Lou, Bing-Sheng; Yang, Yao; Wang, Wen-Cong; Lin, Xiao-Feng

    2016-08-01

    Neutrophils have been recognized as critical response cells during the pathogenesis of endotoxin‑induced uveitis (EIU). Apoptosis of neutrophils induced by roscovitine has previously been demonstrated to ameliorate inflammation in several in vivo models. The present study aimed to assess whether roscovitine ameliorates EIU. EIU was induced in female C57BL/6 mice by a single intravitreal injection of lipopolysaccharide (LPS; 250 ng). The mice were divided into three groups as follows: LPS alone, LPS plus vehicle, LPS plus roscovitine (50 mg/kg). The mice were euthanized 12, 24, 48 and 72 h after LPS‑induced uveitis. Accumulation of inflammatory cells in the vitreous body was confirmed by immunohistochemistry, and quantified following hematoxylin and eosin staining. Terminal deoxynucleotidyl transferase dUTP nick‑end labeling was performed to detect of apoptotic cells. The mRNA levels of inflammatory cytokines were analyzed by reverse transcription‑quantitative polymerase chain reaction and the changes in protein levels were analyzed by western blotting. Inflammatory cells accumulated in the vitreous near the optic nerve head and the quantity peaked at 24 h after LPS injection. Immunohistochemistry revealed that the majority of the inflammatory cells were neutrophils. The number of infiltrating cells was similar in the LPS and LPS plus vehicle groups, while there were significantly less in the roscovitine group at 24 h. Apoptosis of neutrophils was observed between 12 and 48 h after roscovitine injection, while no apoptosis was observed in the other groups. The mRNA expression levels of GMCSF, CINC‑1 and ICAM‑1 peaked at 12 h after LPS injection, and decreased to normal levels at 72 h. This trend in mRNA expression was similar in the LPS and LPS plus vehicle groups; however, the expression levels decreased more quickly in the roscovitine group at 24 and 48 h. Following roscovitine administration, upregulated cleaved caspase 3 expression levels

  8. Alkannin, HSP70 inducer, protects against UVB-induced apoptosis in human keratinocytes.

    Yoko Yoshihisa

    Full Text Available Alkannin is an active constituent from the root extract of Alkanna tinctoria of the Boraginaceae family and it may have utility as a heat shock protein 70 (HSP70 inducer in living organisms. Here, the effects of alkannin-induced HSP70 on ultraviolet (UV B (40 mJ/cm(2-induced apoptosis were investigated in human keratinocyte HaCaT cells. Pretreatment of cells with alkannin (1 µM caused significant inhibition of UVB-induced apoptosis and caspase-3 cleavage. On the other hand, the addition of KNK437 (HSP70 inhibitor reversed the action of alkannin increasing UVB-induced apoptosis in a dose-dependent manner. In addition, differences in gene expression associated with the suppression of UVB-induced apoptosis in the presence of alkannin were investigated using Gene Chip assay. Our results indicate that alkannin suppresses UVB-induced apoptosis through the induction of HSP70 in human keratinocytes, and therefore, we suggest the usefulness of using alkannin as an antiaging agent.

  9. Nitric oxide damages neuronal mitochondria and induces apoptosis in neurons

    2000-01-01

    The cytotoxic effect of nitric oxide on primarily cultured rat cerebellar granule cells was studied,and the mechanisms were discussed.The results showed that nitric oxide donor S-nitroso-N-acetyl-penicillamine (SNAP; 500 μmol/L) could induce apoptosis in immature cultures of cerebellar granule cells.Flow cytometry and HPLC analyses revealed that after treatment with SNAP,the mitochondrial transmembrane potential and the cellular ATP content decreased significantly.Nitric oxide scavenger hemoglobin could effectively prevent the neuronal mitochondria from dysfunction and attenuate apoptosis.The results suggested that nitric oxide activated the apoptotic program by inhibiting the activity of mitochondrial respiratory chain and thus decreasing the cellular ATP content.

  10. Apoptosis in immune cells induced by fission fragment 147Pm

    ZhuShou-Peng; ZhangLan-Sheng; 等

    1997-01-01

    Apoptosis in human acute lymphoblastic leukemia cell line Molt-4 cell and macrophage cell line Ana-1 cell could be induced by fission fragment 147Pm,The cumulative absorption dose of 147Pm in cultural cells through different periods were estimated.By using fluorescence microscopy and microautoradiographic tracing it can be found that Molt-4 and Anal-1 cells internally irradiated by 147Pm,displayed an obvious nuclear fragmentation and a marked phknosis in immune cell nucei,as well as DNA chain fragmentation and apoptotic bodies formation.The microautoradiographic study showed that 147Pm could infiltrate thourgh cell membrane and displayed membrane-seeking condensation in cells.At the same time.the membrane-bounded apoptotic bodies were observed.Experimental results in recent study provide evidence that Molt-4 and Ano-1 immune cells undergo apoptosis while internally irradiated with 147Pm.

  11. Curcumin and Omega-3 Fatty Acids Enhance NK Cell-Induced Apoptosis of Pancreatic Cancer Cells but Curcumin Inhibits Interferon-γ Production: Benefits of Omega-3 with Curcumin against Cancer

    Milan Fiala

    2015-02-01

    Full Text Available STAT-3 and STAT-1 signaling have opposite effects in oncogenesis with STAT-3 acting as an oncogene and STAT-1 exerting anti-oncogenic activities through interferon-γ and interferon-α. The cytokine IL-6 promotes oncogenesis by stimulation of NFκB and STAT-3 signaling. Curcuminoids have bi-functional effects by blocking NFκB anti-apoptotic signaling but also blocking anti-oncogenic STAT-1 signaling and interferon-γ production. In our recent study (unpublished work [1] in pancreatic cancer cell cultures, curcuminoids enhanced cancer cell apoptosis both directly and by potentiating natural killer (NK cell cytotoxic function. The cytotoxic effects of curcuminoids were increased by incubation of cancer cells and NK cells in an emulsion with omega-3 fatty acids and antioxidants (Smartfish, which enhanced cancer cell apoptosis and protected NK cells against degradation. However, as also shown by others, curcuminoids blocked interferon-γ production by NK cells. The combined use of curcuminoids and omega-3 in cancer immunotherapy will require deeper understanding of their in vivo interactions with the immune system.

  12. AIRE-induced apoptosis is associated with nuclear translocation of stress sensor protein GAPDH

    Highlights: ► AIRE induces apoptosis in epithelial cells. ► CARD domain of AIRE is sufficient for apoptosis induction. ► AIRE induced apoptosis involves GAPDH translocation to the nuclei. ► Deprenyl inhibits AIRE induced apoptosis. -- Abstract: AIRE (Autoimmune Regulator) has a central role in the transcriptional regulation of self-antigens in medullary thymic epithelial cells, which is necessary for negative selection of autoreactive T cells. Recent data have shown that AIRE can also induce apoptosis, which may be linked to cross-presentation of these self-antigens. Here we studied AIRE-induced apoptosis using AIRE over-expression in a thymic epithelial cell line as well as doxycycline-inducible HEK293 cells. We show that the HSR/CARD domain in AIRE together with a nuclear localization signal is sufficient to induce apoptosis. In the nuclei of AIRE-positive cells, we also found an increased accumulation of a glycolytic enzyme, glyceraldehyde-3-phosphate (GAPDH) reflecting cellular stress and apoptosis. Additionally, AIRE-induced apoptosis was inhibited with an anti-apoptotic agent deprenyl that blocks GAPDH nitrosylation and nuclear translocation. We propose that the AIRE-induced apoptosis pathway is associated with GAPDH nuclear translocation and induction of NO-induced cellular stress in AIRE-expressing cells.

  13. AIRE-induced apoptosis is associated with nuclear translocation of stress sensor protein GAPDH

    Liiv, Ingrid, E-mail: ingrid.liiv@ut.ee [Molecular Pathology, Institute of General and Molecular Pathology, University of Tartu, Tartu (Estonia); Haljasorg, Uku; Kisand, Kai; Maslovskaja, Julia; Laan, Martti; Peterson, Paert [Molecular Pathology, Institute of General and Molecular Pathology, University of Tartu, Tartu (Estonia)

    2012-06-22

    Highlights: Black-Right-Pointing-Pointer AIRE induces apoptosis in epithelial cells. Black-Right-Pointing-Pointer CARD domain of AIRE is sufficient for apoptosis induction. Black-Right-Pointing-Pointer AIRE induced apoptosis involves GAPDH translocation to the nuclei. Black-Right-Pointing-Pointer Deprenyl inhibits AIRE induced apoptosis. -- Abstract: AIRE (Autoimmune Regulator) has a central role in the transcriptional regulation of self-antigens in medullary thymic epithelial cells, which is necessary for negative selection of autoreactive T cells. Recent data have shown that AIRE can also induce apoptosis, which may be linked to cross-presentation of these self-antigens. Here we studied AIRE-induced apoptosis using AIRE over-expression in a thymic epithelial cell line as well as doxycycline-inducible HEK293 cells. We show that the HSR/CARD domain in AIRE together with a nuclear localization signal is sufficient to induce apoptosis. In the nuclei of AIRE-positive cells, we also found an increased accumulation of a glycolytic enzyme, glyceraldehyde-3-phosphate (GAPDH) reflecting cellular stress and apoptosis. Additionally, AIRE-induced apoptosis was inhibited with an anti-apoptotic agent deprenyl that blocks GAPDH nitrosylation and nuclear translocation. We propose that the AIRE-induced apoptosis pathway is associated with GAPDH nuclear translocation and induction of NO-induced cellular stress in AIRE-expressing cells.

  14. Effects of lysophosphatidylcholine on β-amyloid-induced neuronal apoptosis

    Zhen-xia QIN; Hui-yan ZHU; Ying-he HU

    2009-01-01

    Aim: We have investigated the effects of lysophosphatidylcholine (LPC), a product of lipid peroxidation, on Aβ1-42-induced SH-SY5Y cell apoptosis.Methods: The viability of cultured SH-SY5Y cells was measured using a CCK-8 kit. Apoptosis was determined by Chip-based flow cytometric assay. The mRNA transcription of Bcl-2, Bax, and caspase-3 were detected by using reverse transcrip-tion and real-time quantitative PCR and the protein levels of Bax and caspase-3 were analyzed by Western blotting. Thecytosolic calcium concentration of SH-SY5Y cells was tested by calcium influx assay. GZA expression in SH-SYSY cells wassilenced by small interfering RNA.Results: Long-term exposure of SH-SY5Y cells to LPC augmented the neurotoxicity of Aβ1-42. Furthermore, after LPC treatment, the Bax/Bcl-XL ratio and the expression levels, as well as the activity of caspase-3 were, elevated, whereas the expression level of TRAF1 was reduced. Because LPC was reported to be a specific ligand for the orphan G-protein coupled receptor, G2A, we investigated LPC-mediated changes in calcium levels in SH-SY5Y cells. Our results demonstrated that LPC can enhance the Aβ1-42-induced elevation of intracellular calcium. Interestingly, Aβ1-42 significantly increased the expression of G2A in SH-SY5Y cells, whereas knockdown of G2A using siRNA reduced the effects of LPC on Aβ1-42-induced neurotoxicity.Conclusion: The effects of LPC on Aβ1-42-induced apoptosis may occur through the signal pathways of the orphan G-protein coupled receptor.

  15. Chlorella vulgaris triggers apoptosis in hepatocarcinogenesis-induced rats

    Emey Suhana MOHD AZAMAI; Suhaniza SULAIMAN; Shafina Hanim MOHD HABIB; Mee Lee LOOI; Srijit DAS; Nor Aini ABDUL HAMID; Wan Zurinah WANG NGAH; Yasmin Anum MOHD YUSOF

    2009-01-01

    Chlorella vulgaris (CV) has been reported to have antioxidant and anticancer properties. We evaluated the effect of CV on apoptotic regulator protein expression in liver cancer-induced rats. Male Wistar rats (200-250 g) were divided into eight groups: control group (normal diet), CDE group (choline deficient diet supplemented with ethionine in drinking water to induce hepatocarcinogenesis), CV groups with three different doses of CV (50, 150, and 300 mg/kg body weight), and CDE groups treated with different doses of CV (50, 150, and 300 mg/kg body weight). Rats were sacrificed at various weeks and liver tissues were embedded in paraffin blocks for immunohistochemistry studies. CV, at increasing doses, decreased the expression of anti-apoptotic protein, Bcl-2, but increased the expression of pro-apoptotic protein, caspase 8, in CDE rats, which was correlated with decreased hepatoctyes proliferation and increased apoptosis as determined by bromodeoxy-uridine (BrdU) labeling and terminal deoxynucleotidyl transferase mediated dUTP nick-end labeling (TUNEL) assay, respectively. Our study shows that CV has definite chemopreventive effect by inducing apoptosis via decreasing the expression of Bcl-2 and increasing the expression of caspase 8 in hepatocarcinogenesis-induced rats.

  16. Ursolic Acid Triggers Apoptosis in Human Osteosarcoma Cells via Caspase Activation and the ERK1/2 MAPK Pathway.

    Wu, Chia-Chieh; Cheng, Chun-Hsiang; Lee, Yi-Hui; Chang, Ing-Lin; Chen, Hsin-Yao; Hsieh, Chen-Pu; Chueh, Pin-Ju

    2016-06-01

    Ursolic acid (UA), a naturally occurring pentacyclic triterpene acid found in many medicinal herbs and edible plants, has been shown to trigger apoptosis in several lines of tumor cells in vitro. We found that treatment with UA suppressed the viability of human osteosarcoma MG-63 cells and induced cell cycle arrest at sub-G1 and G2/M phases. Furthermore, exposure to UA induced intracellular oxidative stress and collapse of mitochondrial membrane permeability, resulting in the subsequent activation of apoptotic caspases 8, 9, and 3 as well as PARP cleavage, and ultimately apoptosis in MG-63 cells. Moreover, protein analysis of mitogen-activated protein kinase (MAPK)-related protein expression showed an increase in activated ERK1/2, JNK, and p38 MAPK in UA-treated MG-63 cells. In addition, UA-induced apoptosis was significantly abolished in MG-63 cells that had been pretreated with inhibitors of caspase 3, 8, and 9 and ERK1/2. Furthermore, UA-treated MG-63 cells also exhibited an enhancement in Bax/Bcl-2 ratio, whereas anti-apoptotic XIAP and survivin were down-regulated. Taken together, we provide evidence demonstrating that UA mediates caspase-dependent and ERK1/2 MAPK-associated apoptosis in osteosarcoma MG-63 cells. PMID:27171502

  17. Apoptosis in Raji cell line induced by influenza A virus

    李虹; 肖丽英; 李华林; 李婉宜; 蒋中华; 张林; 李明远

    2003-01-01

    Objective To study the apoptotic effects of influenza A virus on the Raji cell line. Methods Cultured Raji cells were infected with influenza A virus at a multiplicity of infection (m.o.i) of 20 and the effects of apoptosis were detected at different time points post infection using the following methods: electron microscope, DNA agarose gel electrophoresis, PI stained flow cytometry (FCM) and Annexin-V FITC/PI stained FCM.Results Raji cells infected with influenza A virus showed changes of morphology apoptotis, DNA agarose electrophoresis also demonstrated a ladder-like pattern of DNA fragments in a time-dependent manner. PI stained FCM showed "apoptosis peak" and FITC/PI stained FCM showed apoptotic cells. Quantitative analysis indicated that the percentage of apoptotic Raji cells increased after infection, and cycloheximide (CHX), an eukaryotic transcription inhibitor, could effectively inhibit the apoptotic effects of influenza A virus in vitro.Conclusions Influenza A virus can induce apoptosis in Raji cell line suggesting that it may lead to a potential method for tumor therapy.

  18. Blockage of JNK pathway enhances arsenic trioxide-induced apoptosis in human keratinocytes

    Arsenic is well known as a carcinogen predisposing humans to some severe diseases and also as an effective medicine for treating acute promyelocytic leukemia, syphilis, and psoriasis. Multiple active mechanisms, including cell cycle arrest and apoptosis, have been proposed in therapy; however, the opposing effects of arsenic remain controversial. Our previous study found that arsenic trioxide (ATO)-induced activation of p21WAF1/CIP1 (p21) led to A431 cell death through the antagonistic effects of the signaling of ERK1/2 and JNK1. In the current study, the inhibitory effects of JNK1 on ATO-induced p21 expression were explored. Over-expression of JNK1 in A431 cells could inhibit p21 expression, which was associated with HDAC1 and TGIF. Using the GST pull-down assay and fluorescence resonance energy transfer analysis, N-terminal domain (amino acids 1-108) of TGIF, critical to its binding with c-Jun, was found. Using reporter assays, requirement of the C-terminal domain (amino acids 138-272) of TGIF to suppress ATO-induced p21 expression was observed. Thus, the domains of TGIF that carried out its inhibitory effects on p21 were identified. Finally, treatment with JNK inhibitor SP600125 could enhance ATO-induced apoptosis of HaCaT keratinocytes by using flow cytometry.

  19. Effective chemotherapy induce apoptosis in vivo in patients with leukemia

    岑溪南; 朱平; 虞积仁; 石永进; 马明信

    2003-01-01

    Objective To investigate apoptosis in vivo in patients with leukemia at different stages of the first cycle of chemotherapy.Methods We detected apoptosis of HL-60 cells and peripheral blood leukemia cells in 17 patients at different stages, using in situ terminal deoxynucleotidyl transferase (TdT) fluorescence measurement and DNA electrophoresis. Results When HL-60 cells were incubated with 0.02 mg/L harringtonine for 0 to 48 hours, agarose gel electrophoresis showed that DNA ladder patterns became evident only at 12 hour into the treatment. In situ TdT assay showed that apoptotic cells occurred after one hour of the treatment. Apoptotic cells were few (0-3.3%) before chemotherapy, but increased substantially (11.4%-87.5%) during chemotherapy in patients with complete remission (CR) or partial remission (PR). Apoptotic cells were few (0-6.1%) during chemotherapy in ten patients with no remission (NR). DNA ladder cannot be detected by agarose gel electrophoresis either before, during or after chemotherapy. Wilcoxon signed rank test shows: P=0.0012<0.01, apoptotic cells during chemotherapy were present in greater quantity than prior to chemotherapy. Wilcoxon rank sum test shows: P=0.0011<0.01, with the median of apoptotic cells during chemotherapy in patients with CR or PR more than with NR.Conclusions TdT assay can be used to detect apoptotic cells earlier and more sensitively than DNA agarose gel electrophoresis. In situ TdT assay is useful to detect apoptosis in vivo in the initial phase of chemotherapy for immediate modification of the chemotherapy regimen, whereas electrophoretic analysis is not sensitive enough to detect apoptotic cell in vivo. Where the median of apoptotic cells during chemotherapy in patients with CR or PR were greater than with NR, only effective drug therapy could induce apoptosis.

  20. Swainsonine-induced apoptosis pathway in cerebral cortical neurons.

    Lu, Hao; Ma, Feng; Zhang, Liang; Wang, Jianguo; Wu, Chenchen; Zhao, Baoyu

    2015-10-01

    Swainsonine (SW) is an indolizidine alkaloid, and the principal toxic component of the poisonous legume plants Astragalus and Oxytropis sp. Animals that consume the toxic plants show neurologic symptoms. In this study, the cerebral cortical neurons of primary culture were treated for 12h with various concentrations of SW. The [Ca(2+)]i and the protein expression of caspase-3, -8, -9 and -12 were assessed in all experimental groups. In comparison with the control group, [Ca(2+)]i increased significantly in SW-treated groups (P0.05). The results suggest that SW induced the apoptosis of neurons through a death receptor pathway and endoplasmic reticulum stress. PMID:26412516

  1. 藤黄酸诱导Burkitt淋巴瘤细胞株凋亡及增殖抑制的分子学机制%Molecular Mechanism of Apoptosis and Proliferation Inhibition Induced by Gambogic Acid in Burkitt Lymphoma Cell Line

    师宪平; 蓝晓莹; 李雅楠; 温创宇; 黄美近; 刘焕亮

    2013-01-01

    [Objective] To study the influence of gambogic acid on the proliferation and cell apoptosis of Burkitt lymphoma cells Namalva,and provide basis for clinical treatment of Burkitt lymphoma.[Methods] Burkitt lymphoma cells were treated with different doses of gambogic acid.The cell viability and proliferation were evaluated by MTS assay.Cells were treated with 0.25,0.5,and 0.75 μmol/L gambogic acid for 24 hours,and 0.75 μmol/L gambogic acid for respectively 6,12,and 24 h.The dose-dependent cell apoptosis was detected using flow cytometry with Annexin V-FTIC/PI staining.The dose-and time-dependent changes of apoptosis and proliferation-related proteins were tested by Western blotting.[Results] The cell viability was inhibited by gambogic acid.Gambogic acid induced Namalva cell apoptosis and the cleavage of PARP and caspase 8,upregulated Bax,and decreased the expression of Pro-caspase 3,Pro-caspase 9,and Bcl-2 as well as proliferation pathway and related protein STAT5,p-STAT5,ERK,p-ERK in a dose and time dependent manner.[Conclusion] Gambogic acid induces cell apoptosis by effecting the expression of apoptosis related proteins and inhibits cell proliferation by down-regulating the activation of JAKs/STATs,MEK/ERK signal transduction pathway in Burkitt lymphoma cells.%[目的]研究藤黄酸对Burkitt淋巴瘤细胞株Namalva细胞增殖与凋亡的影响及其分子学机制,探讨藤黄酸治疗Burkitt淋巴瘤的潜在应用价值.[方法]用不同剂量藤黄酸处理细胞,采用MTS法对淋巴瘤细胞进行细胞活力及增殖抑制测定;0.25、0.5、0.75μmol/L藤黄酸分别处理细胞24 h,0.75μmol/L藤黄酸分别处理细胞6、12、24h后收集细胞,采用Annexin V-FTIC/PI流式细胞术检测藤黄酸剂量依赖性细胞凋亡情况;利用Western blot方法检测凋亡相关蛋白和细胞增殖信号通路相关蛋白剂量与时间依赖的变化情况.[结果]藤黄酸明显抑制Namalva细胞的增殖,诱导Namalva细胞发生凋亡.随藤黄

  2. Involvement of FKHR-Dependent TRADD Expression in Chemotherapeutic Drug-Induced Apoptosis

    Rokudai, Susumu; Fujita, Naoya; Kitahara, Osamu; NAKAMURA, Yusuke; Tsuruo, Takashi

    2002-01-01

    Chemotherapeutic drugs exhibit their cytotoxic effect by inducing apoptosis in tumor cells. Because the serine/threonine kinase Akt is involved in apoptosis suppression, we investigated the relationship between Akt activity and drug sensitivity. We discovered that certain chemotherapeutic drugs induced apoptosis with caspase activation only when Akt was inactivated after drug treatment, while inactivation of Akt was not observed when tumor cells showed resistance to the drug-induced caspase a...

  3. Possible involvement of DNA methylation in 5-azacytidine-induced neuronal cell apoptosis

    Nakayama, Hiroyuki; Kajikawa, S.; Shinozuka, J.; Su, W. P.; Doi, K

    1999-01-01

    Eight chemicals that are cytidine analogues or nucleosides (5-azacytidine (SAzC), 5-azadeoxycytidine, 6-azacytidine, 5-azacytosin, cytidine, 3-deazaadenine, 3-deazauridine and 6-azauridine) were examined for the ability to induce neuronal apoptosis. 5AzC and 5-azadeoxycytidine induced apoptosis in the brain and spinal cord of the fetuses at 24 hr after the injection to dams, while the other chemicals tested failed to induce apoptosis. In the system of PC12 cell...

  4. Effects of topiramate on hippocampal neuronal apoptosis in rats after kainic acid-evoked seizures

    Yuan Wu; Jiarong Pang; Jinou Zheng; Xiaoqing Deng; Xiulin Liang; Jiaquan Li; Zhiying Chen

    2008-01-01

    tissues of hippocampal dentate gyrus,CA1,CA2,and CA3 region were removed and prepared into sections.Neuronal apoptosis was detected with in situ terminal deoxynucleotidyl transferase dUTP nick-end labeling.MAIN OUTCOME MEASURES:Hippocampal neuronal apoptosis in various rat brain areas was detected in the two groups.RESULTS:All 60 rats were included in the final analysis of results.In the topiramate-treated group,the number of apoptotic cells in hippocampal dentate gyrus and CA3 region at 1 day,1,and 4 weeks after seizures were significantly lower than the model group(P<0.054-0.01).The number of apoptotic cells in hippocampal CA1 and CA2 regions at 1 day and 4 weeks after seizures in the topiramate-treated group were significantly lower than the model group(P<0.05).CONCLUSION:Hippocampal apoptosis is closely associated with kainic acid-evoked seizures,and topiramate can alleviate early(1 day and 1 week)and delayed(4 weeks)hippocampal neuronal injury induced by kainic acid.

  5. Superoxide-mediated proteasomal degradation of Bcl-2 determines cell susceptibility to Cr(VI)-induced apoptosis

    Azad, Neelam; Iyer, Anand Krishnan V.; Manosroi, Aranya; Wang, Liying; Rojanasakul, Yon

    2008-01-01

    Hexavalent chromium [Cr(VI)] compounds are redox cycling environmental carcinogens that induce apoptosis as the primary mode of cell death. Defects in apoptosis regulatory mechanisms contribute to carcinogenesis induced by Cr(VI). Activation of apoptosis signaling pathways is tightly linked with the generation of reactive oxygen species (ROS). Likewise, ROS have been implicated in the regulation of Cr(VI)-induced apoptosis and carcinogenicity; however, its role in Cr(VI)-induced apoptosis and...

  6. Apoptosis induced by radionuclide 153Sm and expression of relevant genes in three different cancer cells

    To study apoptosis of PC-3, ER-75-30 and A549 cells induced by radionuclide 153Sm and the expression of bcl-2, bax in apoptosis cells, MTT assay was used to detect the anti-tumor effect, light microscope, transmission electron microscope, flow cytometer were used to detect apoptosis, while image analysis was used to detect the expression of bcl-2 and bax. 153Sm showed anti-tumor effect and could induce tumor cell apoptosis. Both bcl-2 and bax played an important role in apoptosis. Different kind of cells had different sensitivity to 153Sm

  7. SDZ诱导lovo细胞凋亡%SDZ-induced apoptosis in Iovo cells

    Ruijin Song; Li Feng; Jinxue Tong

    2009-01-01

    Objective: To explore the inhibition effective of the SDZ on Iovo cell growth of colon cancer in vitro. Methods:The apoptosis was observed by Hoechst fluorescein stain and transmission electron microscope. Results: The apoptosis was observed after the Iovo ceils treated by SDZ (1000 μg/mL) for 24 h. The rate of apoptosis was 30.2%. Conclusion: The apoptosis of Iovo cells can be induced by SDZ in vitro.

  8. Specific antibodies induce apoptosis in Trypanosoma cruzi epimastigotes.

    Fernández-Presas, Ana María; Tato, Patricia; Becker, Ingeborg; Solano, Sandra; Copitin, Natalia; Kopitin, Natalia; Berzunza, Miriam; Willms, Kaethe; Hernández, Joselin; Molinari, José Luis

    2010-05-01

    The susceptibility of Trypanosoma cruzi epimastigotes to lysis by normal or immune sera in a complement-dependent reaction has been reported. Mouse immune sera depleted complement-induced damage in epimastigotes characterized by morphological changes and death. The purpose of this work was to study the mechanism of death in epimastigotes exposed to decomplemented mouse immune serum. Epimastigotes were maintained in RPMI medium. Immune sera were prepared in mice by immunization with whole crude epimastigote extracts. Viable epimastigotes were incubated with decomplemented normal or immune sera at 37 degrees C. By electron microscopy, agglutinated parasites showed characteristic patterns of membrane fusion between two or more parasites; this fusion also produced interdigitation of the subpellicular microtubules. Apoptosis was determined by flow cytometry using terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) and annexin V assays. Nuclear features were examined by 4'-,6-diamidino-2'-phenylindole diHCI cytochemistry that demonstrated apoptotic nuclear condensation. Caspase activity was also measured. TUNEL results showed that parasites incubated with decomplemented immune sera took up 26% of specific fluorescence as compared to 1.3% in parasites incubated with decomplemented normal sera. The Annexin-V-Fluos staining kit revealed that epimastigotes incubated with decomplemented immune sera exposed phosphatidylserine on the external leaflet of the plasma membrane. The incubation of parasites with immune sera showed caspase 3 activity. We conclude that specific antibodies are able to induce agglutination and apoptosis in epimastigotes, although the pathway is not elucidated. PMID:20237802

  9. Aloe-emodin-induced apoptosis in human gastric carcinoma cells.

    Chen, Sheng-Hsuan; Lin, Kai-Yuan; Chang, Chun-Chao; Fang, Chia-Lang; Lin, Chih-Ping

    2007-11-01

    The purpose of this study was to investigate the anticancer effect of aloe-emodin, an anthraquinone compound present in the leaves of Aloe vera, on two distinct human gastric carcinoma cell lines, AGS and NCI-N87. We demonstrate that aloe-emodin induced cell death in a dose- and time-dependent manner. Noteworthy is that the AGS cells were generally more sensitive than the NCI-N87 cells. Aloe-emodin caused the release of apoptosis-inducing factor and cytochrome c from mitochondria, followed by the activation of caspase-3, leading to nuclear shrinkage and apoptosis. In addition, exposure to aloe-emodin suppressed the casein kinase II activity in a time-dependent manner and was accompanied by a reduced phosphorylation of Bid, a downstream substrate of casein kinase II and a pro-apoptotic molecule. These preclinical studies suggest that aloe-emodin represents a suitable and novel chemotherapeutic drug candidate for the treatment of human gastric carcinoma. PMID:17637488

  10. Involvement of FAN in TNF-induced apoptosis.

    Ségui, B; Cuvillier, O; Adam-Klages, S; Garcia, V; Malagarie-Cazenave, S; Lévêque, S; Caspar-Bauguil, S; Coudert, J; Salvayre, R; Krönke, M; Levade, T

    2001-07-01

    TNF-alpha is a pleiotropic cytokine activating several signaling pathways initiated at distinct intracellular domains of the TNF receptors. Although the C-terminal region is believed to be responsible for apoptosis induction, the functions of more membrane-proximal domains, including the domain that couples to neutral sphingomyelinase activation, are not yet fully elucidated. The roles of this region and of the associated adapter protein FAN (factor associated with neutral SMase activation) in the cytotoxic response to TNF have been investigated. We have now shown that stable expression in human fibroblasts of a dominant negative form of FAN abrogates TNF-induced ceramide generation from sphingomyelin hydrolysis and reduces caspase processing, thus markedly inhibiting TNF-triggered apoptosis. However, the cytotoxic responses to daunorubicin and exogenous ceramide remain unaltered, as do the TNF-induced p42/p44 MAPK activation and CD54 expression. Fibroblasts from FAN-knockout mice also proved to be resistant to TNF toxicity. These findings highlight the previously unrecognized role of the adapter protein FAN in signaling cell death induction by TNF. PMID:11435466

  11. ROS Induce Cardiomyocyte Apoptosis in Ascitic Broiler Chickens

    Zhaofang Xi§, Shijin Yang§, Dongyang Liu, Liming Wu, Xiaodong Liu, Jing Zhao and Dingzong Guo*

    2012-10-01

    Full Text Available It is believed that ascitic broilers die of right heart failure caused by pulmonary hypertension, but the underlying mechanisms of right heart failure are unknown. However, recent studies have shown that reactive oxygen species have the ability to damage heart cells. This study aimed to determine the changes of reactive oxygen species in serum and plasma, and the effect of this variation on myocardial cells during broiler ascites. We used hypoxia and a low-temperature method to induce broiler ascites in the fast-growing group. For controls, we treated a slow-growing group of broilers with 70% restricted feeding under the same circumstances as the fast-growing group. The results showed that hypoxia is a more effective and better way to induce broiler ascites than a low-temperature environment and high growth rate. In addition, reactive oxygen species levels were significantly increased in the fast-growing group compared with those in the slow-growing group. This significant increase in reactive oxygen species resulted in myocardial cell apoptosis in the fast-growing group. Our results suggest that cardiomyocyte apoptosis caused by increased reactive oxygen species levels of ascitic broilers is one of the most important reasons for causing heart failure.

  12. Regulation of apoptosis and innate immune stimuli in inflammation-induced preterm labor.

    Jaiswal, Mukesh K; Agrawal, Varkha; Mallers, Timothy; Gilman-Sachs, Alice; Hirsch, Emmet; Beaman, Kenneth D

    2013-12-01

    An innate immune response is required for successful implantation and placentation. This is regulated, in part, by the a2 isoform of V-ATPase (a2V) and the concurrent infiltration of M1 (inflammatory) and M2 (anti-inflammatory) macrophages to the uterus and placenta. The objective of the present study was to identify the role of a2V during inflammation-induced preterm labor in mice and its relationship to the regulation of apoptosis and innate immune responses. Using a mouse model of infection-induced preterm delivery, gestational tissues were collected 8 h after intrauterine inoculation on day 14.5 of pregnancy with either saline or peptidoglycan (PGN; a TLR 2 agonist) and polyinosinic-polycytidylic acid [poly(I:C); a TLR3 agonist], modeling Gram-positive bacterial and viral infections, respectively. Expression of a2V decreased significantly in the placenta, uterus, and fetal membranes during PGN+poly(I:C)-induced preterm labor. Expression of inducible NO synthase was significantly upregulated in PGN+poly(I:C)-treated placenta and uterus. PGN+poly(I:C) treatment disturbed adherens junction proteins and increased apoptotic cell death via an extrinsic pathway of apoptosis among uterine decidual cells and spongiotrophoblasts. F4/80(+) macrophages were increased and polarization was skewed in PGN+poly(I:C)-treated uterus toward double-positive CD11c(+) (M1) and CD206(+) (M2) cells, which are critical for the clearance of dying cells and rapid resolution of inflammation. Expression of Nlrp3 and activation of caspase-1 were increased in PGN+poly(I:C)-treated uterus, which could induce pyroptosis. These results suggest that the double hit of PGN+poly(I:C) induces preterm labor via reduction of a2V expression and simultaneous activation of apoptosis and inflammatory processes. PMID:24163412

  13. Pigment Epithelium-Derived Factor (PEDF) Protects Osteoblastic Cell Line from Glucocorticoid-Induced Apoptosis via PEDF-R.

    Yao, Shengcheng; Zhang, Yingnan; Wang, Xiaoyu; Zhao, Fengchao; Sun, Maji; Zheng, Xin; Dong, Hongyan; Guo, Kaijin

    2016-01-01

    Pigment epithelial-derived factor (PEDF) is known as a widely expressed multifunctional secreted glycoprotein whose biological actions are cell-type dependent. Recent studies demonstrated that PEDF displays cytoprotective activity in several cell types. However, it remains unknown whether PEDF is involved in glucocorticoid-induced osteoblast death. The aim of this study was to examine the role of PEDF in osteoblast survival in response to dexamethasone, an active glucocorticoid analogue, and explore the underlying mechanism. In the present study, dexamethasone (DEX) was used to induce MC3T3-E1 pre-osteoblast apoptosis. PEDF mRNA and protein levels and cell apoptosis were determined respectively. Then PEDF receptor (PEDF-R)- and lysophosphatidic acid (LPA)-related signal transductions were assessed. Here we show that DEX down-regulates PEDF expression, which contributes to osteoblast apoptosis. As a result, exogenous recombinant PEDF (rPEDF) inhibited DEX-induced cell apoptosis. We confirmed that PEDF-R was expressed on MC3T3-E1 pre-osteoblast membrane and could bind to PEDF which increased the level of LPA and activated the phosphorylation of Akt. Our results suggest that PEDF attenuated DEX-induced apoptosis in MC3T3-E1 pre-osteoblasts through LPA-dependent Akt activation via PEDF-R. PMID:27187377

  14. NP24 induces apoptosis dependent on caspase-like activity in Saccharomyces cerevisiae.

    Higuchi, Naoki; Ito, Yasuhiro; Kato, Jun; Ogihara, Jun; Kasumi, Takafumi

    2016-06-01

    Tomato NP24 is a homolog of osmotin, a PR-5 protein from tobacco that can initiate apoptosis in yeast via PHO36 in the plasma membrane. We cloned and sequenced NP24 from tomato cv. Momotaro. Based on phylogenetic analysis, NP24 from Momotaro belonged to the Solanaceae clade. The amino acid sequence was identical to that of cv. Ailsa Craig including signal peptide, but the residues predicted to interact with the adiponectin receptor, ADIPOR, were slightly different from osmotin. Recombinant NP24 (rNP24) was expressed in a reductase-deficient mutant of Escherichia coli as host cell, and purified from cell extract by affinity chromatography. Purified rNP24 significantly inhibited growth of Saccharomyces cerevisiae wild-type spheroplasts. In contrast, growth of PHO36 deletion mutant (ΔIzh2) spheroplasts was not inhibited. Moreover, rNP24 induced significant activity of reactive oxygen species, caspase-like activity, and also nuclear fragmentation in wild-type spheroplast cells. These results demonstrated that rNP24 from Momotaro greatly influenced cell viability due to triggering apoptosis through PHO36. Notably, apoptosis induced by NP24 was caspase-like protease dependent. PMID:26589784

  15. Apoptosis mechanism of human cholangiocarcinoma cells induced by bile extract from crocodile.

    Kang, Jin-He; Zhang, Wen-Qing; Song, Wei; Shen, Dong-Yan; Li, Shan-Shan; Tian, Ling; Shi, Yan; Liang, Ge; Xiong, You-Xiong; Chen, Qing-Xi

    2012-02-01

    Animal bile is popularly used as a traditional medicine in China, and bile acids are their major bioactive constituents. In the present study, effects of bile extract from crocodile gallbladder on QBC939 cell growth, cell cycle, and apoptosis were investigated by MTT assay, inverted microscopy, fluorescence microscopy, transmission electron microscopy, scanning electron microscopy, PI single- and FITC/PI double-staining flow cytometry, and western blotting. Our data have revealed that bile extract inhibited cells growth significantly, and the cell cycle was arrested in G1 phase. Bile extract induced QBC939 cell apoptosis, which was associated with collapse of the mitochondrial membrane potential and increase of ROS. In bile extract-treated cells, it was observed that the expression of bcl-2 decreased and cytochrome c released to cytosol, but the expression of bax remained unchanged. The data indicated that mitochondrial pathway might play an important role in bile extract-induced apoptosis in QBC939 cells. These results provide significant insight into the anticarcinogenic action of bile extract on cholangiocarcinoma cells. PMID:22194052

  16. Dietary antioxidants protect gut epithelial cells from oxidant-induced apoptosis

    Bobrowski Paul

    2001-12-01

    Full Text Available Abstract Background The potential of ascorbic acid and two botanical decoctions, green tea and cat's claw, to limit cell death in response to oxidants were evaluated in vitro. Methods Cultured human gastric epithelial cells (AGS or murine small intestinal epithelial cells (IEC-18 were exposed to oxidants – DPPH (3 μM, H2O2 (50 μM, peroxynitrite (300 μM – followed by incubation for 24 hours, with antioxidants (10 μg/ml administered as a 1 hour pretreatment. Cell number (MTT assay and death via apoptosis or necrosis (ELISA, LDH release was determined. The direct interactions between antioxidants and DPPH (100 μM or H2O2 (50 μM were evaluated by spectroscopy. Results The decoctions did not interact with H2O2, but quenched DPPH although less effectively than vitamin C. In contrast, vitamin C was significantly less effective in protecting human gastric epithelial cells (AGS from apoptosis induced by DPPH, peroxynitrite and H2O2 (P 2O2, but green tea was more effective than cat's claw in reducing DPPH-induced apoptosis (P 2O2, and was attenuated both by cat's claw and green tea (P Conclusions These results indicate that dietary antioxidants can limit epithelial cell death in response to oxidant stress. In the case of green tea and cat's claw, the cytoprotective response exceed their inherent ability to interact with the injurious oxidant, suggestive of actions on intracellular pathways regulating cell death.

  17. Metformin prevents methylglyoxal-induced apoptosis of mouse Schwann cells

    Methylglyoxal (MG) is involved in the pathogenesis of diabetic complications via the formation of advanced glycation end products (AGEs) and reactive oxygen species (ROS). To clarify whether the antidiabetic drug metformin prevents Schwann cell damage induced by MG, we cultured mouse Schwann cells in the presence of MG and metformin. Cell apoptosis was evaluated using Hoechst 33342 nuclear staining, caspase-3 activity, and c-Jun-N-terminal kinase (JNK) phosphorylation. Intracellular ROS formation was determined by flow cytometry, and AMP-activated kinase (AMPK) phosphorylation was also examined. MG treatment resulted in blunted cell proliferation, an increase in the number of apoptotic cells, and the activation of caspase-3 and JNK along with enhanced intracellular ROS formation. All of these changes were significantly inhibited by metformin. No significant activation of AMPK by MG or metformin was observed. Taken together, metformin likely prevents MG-induced apoptotic signals in mouse Schwann cells by inhibiting the formation of AGEs and ROS

  18. Mechanism of retinoid receptors in inhibiting proliferation and inducing apoptosis of human melanoma cell line A375

    NIU Xin-wu; PENG Zhen-hui; FENG Jie; MA Hui-qun; LIU Chao; YUAN Jing-yi

    2005-01-01

    @@ Malignant melanoma is a common cancer of skin. Its incidence is growing rapidly in recent years,1 however, there is no effective therapy for this cancer. Retinoids are metabolites or derivatives of vitamin A. They are essential for growth, differentiation, and maintenance of epithelial tissues.2 Previous studies showed that retinoids could inhibit growth of many kinds of malignant tumor cell lines and induce its apoptosis,3,4 including malignant melanoma cell lines.5 Some retinoids have therapeutic action to malignant melanoma, such as all-trans retinoic acid (ATRA) and 13-cis-RA.6,7 Retinoids take effects mainly through two kinds of nuclear receptors, retinoic acid receptor (RAR) and retinoic acid X receptor (RXR). In this study, we have investigated the effects of diverse retinoids and receptor agonists in inhibiting proliferation and inducing apoptosis of human melanoma cell line A375.

  19. Positive and negative regulation of radiation-induced apoptosis by protein kinase C

    Indicators such as clonogenic survival, transformation, and chromosomal aberrations are used to evaluate the effects of radiation on cells. Apoptosis, another such indicator, is a mode of cell death, and radiation-induced apoptosis contributes to eliminating damaged cells and preventing malformation and carcinogenesis. Understanding radiation-induced apoptosis will assist in radiotherapy for cancer and treatment of patients in accidental radiation exposure. Protein kinase C (PKC) is a serine/threonine kinase that is related to cell proliferation, differentiation, metabolism, and apoptosis, and has many roles in the radiation-induced cellular responses involving apoptosis. This review describes the functions of PKC, including its relationship with other signaling networks and oxidative stress in the regulation of radiation-induced apoptosis. Such information might provide clues for evaluating the effects of radiation and for identifying clinical applications. (author)

  20. Human retinal pigment epithelial cell-induced apoptosis in activated T cells

    Jørgensen, A; Wiencke, A K; la Cour, M;

    1998-01-01

    apoptosis was detected by 7-amino-actinomycin D and annexin V staining. RESULTS: Retinal pigment epithelial cells expressed FasL and induced apoptosis in activated Fas+ T cells. Blocking of Fas-FasL interaction with antibody strongly inhibited RPE-mediated T-cell apoptosis. Retinal pigment epithelial cells...... human retinal pigment epithelial (RPE) cells can induce apoptosis in activated T cells. METHODS: Fas ligand (FasL) expression was detected by flow cytometry and immunohistochemistry. Cultured RPE cells were cocultured with T-cell lines and peripheral blood lymphocytes for 6 hours to 2 days. Induction of...... induced apoptosis in several activated T-cell populations and T-cell lines, including T-cell antigen receptor (TCR)-CD3-negative T-cell lines. In contrast, RPE cells induced little or no apoptosis in resting peripheral T cells. Major histocompatibility complex (MHC) class II monoclonal antibodies, which...

  1. HIV-1 Vpr-induced apoptosis is cell cycle dependent and requires Bax but not ANT.

    Joshua L Andersen

    2006-12-01

    Full Text Available The HIV-1 accessory protein viral protein R (Vpr causes G2 arrest and apoptosis in infected cells. We previously identified the DNA damage-signaling protein ATR as the cellular factor that mediates Vpr-induced G2 arrest and apoptosis. Here, we examine the mechanism of induction of apoptosis by Vpr and how it relates to induction of G2 arrest. We find that entry into G2 is a requirement for Vpr to induce apoptosis. We investigated the role of the mitochondrial permeability transition pore by knockdown of its essential component, the adenine nucleotide translocator. We found that Vpr-induced apoptosis was unaffected by knockdown of ANT. Instead, apoptosis is triggered through a different mitochondrial pore protein, Bax. In support of the idea that checkpoint activation and apoptosis induction are functionally linked, we show that Bax activation by Vpr was ablated when ATR or GADD45alpha was knocked down. Certain mutants of Vpr, such as R77Q and I74A, identified in long-term nonprogressors, have been proposed to inefficiently induce apoptosis while activating the G2 checkpoint in a normal manner. We tested the in vitro phenotypes of these mutants and found that their abilities to induce apoptosis and G2 arrest are indistinguishable from those of HIV-1NL4-3 vpr, providing additional support to the idea that G2 arrest and apoptosis induction are mechanistically linked.

  2. Prolactin induces apoptosis of lactotropes in female rodents.

    Jimena Ferraris

    Full Text Available Anterior pituitary cell turnover occurring during female sexual cycle is a poorly understood process that involves complex regulation of cell proliferation and apoptosis by multiple hormones. In rats, the prolactin (PRL surge that occurs at proestrus coincides with the highest apoptotic rate. Since anterior pituitary cells express the prolactin receptor (PRLR, we aimed to address the actual role of PRL in the regulation of pituitary cell turnover in cycling females. We showed that acute hyperprolactinemia induced in ovariectomized rats using PRL injection or dopamine antagonist treatment rapidly increased apoptosis and decreased proliferation specifically of PRL producing cells (lactotropes, suggesting a direct regulation of these cell responses by PRL. To demonstrate that apoptosis naturally occurring at proestrus was regulated by transient elevation of endogenous PRL levels, we used PRLR-deficient female mice (PRLRKO in which PRL signaling is totally abolished. According to our hypothesis, no increase in lactotrope apoptotic rate was observed at proestrus, which likely contributes to pituitary tumorigenesis observed in these animals. To decipher the molecular mechanisms underlying PRL effects, we explored the isoform-specific pattern of PRLR expression in cycling wild type females. This analysis revealed dramatic changes of long versus short PRLR ratio during the estrous cycle, which is particularly relevant since these isoforms exhibit distinct signaling properties. This pattern was markedly altered in a model of chronic PRLR signaling blockade involving transgenic mice expressing a pure PRLR antagonist (TGΔ1-9-G129R-hPRL, providing evidence that PRL regulates the expression of its own receptor in an isoform-specific manner. Taken together, these results demonstrate that i the PRL surge occurring during proestrus is a major proapoptotic signal for lactotropes, and ii partial or total deficiencies in PRLR signaling in the anterior pituitary

  3. Production of Multiple Brain-Like Ganglioside Species Is Dispensable for Fas-Induced Apoptosis of Lymphoid Cells

    Popa, Iuliana; Therville, Nicole; Carpentier, Stéphane; Levade, Thierry; Cuvillier, Olivier; Portoukalian, Jacques

    2011-01-01

    Activation of an acid sphingomyelinase (aSMase) leading to a biosynthesis of GD3 disialoganglioside has been associated with Fas-induced apoptosis of lymphoid cells. The present study was undertaken to clarify the role of this enzyme in the generation of gangliosides during apoptosis triggered by Fas ligation. The issue was addressed by using aSMase-deficient and aSMase-corrected cell lines derived from Niemann-Pick disease (NPD) patients. Fas cross-linking elicited a rapid production of larg...

  4. Avenanthramides Prevent Osteoblast and Osteocyte Apoptosis and Induce Osteoclast Apoptosis in Vitro in an Nrf2-Independent Manner

    Gretel G. Pellegrini

    2016-07-01

    Full Text Available Oats contain unique bioactive compounds known as avenanthramides (AVAs with antioxidant properties. AVAs might enhance the endogenous antioxidant cellular response by activation of the transcription factor Nrf2. Accumulation of reactive oxygen species plays a critical role in many chronic and degenerative diseases, including osteoporosis. In this disease, there is an imbalance between bone formation by osteoblasts and bone resorption by osteoclasts, which is accompanied by increased osteoblast/osteocyte apoptosis and decreased osteoclast apoptosis. We investigated the ability of the synthethic AVAs 2c, 2f and 2p, to 1-regulate gene expression in bone cells, 2-affect the viability of osteoblasts, osteocytes and osteoclasts, and the generation of osteoclasts from their precursors, and 3-examine the potential involvement of the transcription factor Nrf2 in these actions. All doses of AVA 2c and 1 and 5 µM dose of 2p up-regulated collagen 1A expression. Lower doses of AVAs up-regulated OPG (osteoprotegerin in OB-6 osteoblastic cells, whereas 100 μM dose of 2f and all concentrations of 2c down-regulated RANKL gene expression in MLO-Y4 osteocytic cells. AVAs did not affect apoptosis of OB-6 osteoblastic cells or MLO-Y4 osteocytic cells; however, they prevented apoptosis induced by the DNA topoisomerase inhibitor etoposide, the glucocorticoid dexamethasone, and hydrogen peroxide. AVAs prevented apoptosis of both wild type (WT and Nrf2 Knockout (KO osteoblasts, demonstrating that AVAs-induced survival does not require Nrf2 expression. Further, KO osteoclast precursors produced more mature osteoclasts than WT; and KO cultures exhibited less apoptotic osteoclasts than WT cultures. Although AVAs did not affect WT osteoclasts, AVA 2p reversed the low apoptosis of KO osteoclasts. These in vitro results demonstrate that AVAs regulate, in part, the function of osteoblasts and osteocytes and prevent osteoblast/osteocyte apoptosis and increase osteoclast

  5. Avenanthramides Prevent Osteoblast and Osteocyte Apoptosis and Induce Osteoclast Apoptosis in Vitro in an Nrf2-Independent Manner.

    Pellegrini, Gretel G; Morales, Cynthya C; Wallace, Taylor C; Plotkin, Lilian I; Bellido, Teresita

    2016-01-01

    Oats contain unique bioactive compounds known as avenanthramides (AVAs) with antioxidant properties. AVAs might enhance the endogenous antioxidant cellular response by activation of the transcription factor Nrf2. Accumulation of reactive oxygen species plays a critical role in many chronic and degenerative diseases, including osteoporosis. In this disease, there is an imbalance between bone formation by osteoblasts and bone resorption by osteoclasts, which is accompanied by increased osteoblast/osteocyte apoptosis and decreased osteoclast apoptosis. We investigated the ability of the synthethic AVAs 2c, 2f and 2p, to 1-regulate gene expression in bone cells, 2-affect the viability of osteoblasts, osteocytes and osteoclasts, and the generation of osteoclasts from their precursors, and 3-examine the potential involvement of the transcription factor Nrf2 in these actions. All doses of AVA 2c and 1 and 5 µM dose of 2p up-regulated collagen 1A expression. Lower doses of AVAs up-regulated OPG (osteoprotegerin) in OB-6 osteoblastic cells, whereas 100 μM dose of 2f and all concentrations of 2c down-regulated RANKL gene expression in MLO-Y4 osteocytic cells. AVAs did not affect apoptosis of OB-6 osteoblastic cells or MLO-Y4 osteocytic cells; however, they prevented apoptosis induced by the DNA topoisomerase inhibitor etoposide, the glucocorticoid dexamethasone, and hydrogen peroxide. AVAs prevented apoptosis of both wild type (WT) and Nrf2 Knockout (KO) osteoblasts, demonstrating that AVAs-induced survival does not require Nrf2 expression. Further, KO osteoclast precursors produced more mature osteoclasts than WT; and KO cultures exhibited less apoptotic osteoclasts than WT cultures. Although AVAs did not affect WT osteoclasts, AVA 2p reversed the low apoptosis of KO osteoclasts. These in vitro results demonstrate that AVAs regulate, in part, the function of osteoblasts and osteocytes and prevent osteoblast/osteocyte apoptosis and increase osteoclast apoptosis; further

  6. Radiation-induced apoptosis and developmental disturbance of the brain

    Inouye, Minoru [Nagoya Univ. (Japan). Research Inst. of Environmental Medicine

    1995-03-01

    The developing mammalian brain is highly susceptible to ionizing radiation. A significant increase in small head size and mental retardation has been noted in prenatally exposed survivors of the atomic bombing, with the highest risk in those exposed during 8-15 weeks after fertilization. This stage corresponds to day 13 of pregnancy for mice and day 15 for rats in terms of brain development. The initial damage produced by radiation at this stage is cell death in the ventricular zone (VZ) of the brain mantle, the radiosensitive germinal cell population. During histogenesis of the cerebellum the external granular layer (EGL) is also radiosensitive. Although extensive cell death results in microcephaly and histological abnormlity, both VZ and EGL have an ability to recover from a considerable cell loss and form the normal structure of the central nervous system. The number of cell deaths to induce tissue abnormalities in adult brain rises in the range of 15-25% of the germinal cell population; and the threshold doses are about 0.3 Gy for cerebral defects and 1 Gy for cerebellar anomalies in both mice and rats. A similar threshold level is suggested in human cases in induction of mental retardation. Radiation-induced cell death in the VZ and EGL has been revealed as apoptosis, by the nuclear and cytoplasmic condensation, transglutaminase activation, required macromolecular synthesis, and internucleosomal DNA cleavage. Apoptosis of the germinal cell is assumed to eliminate acquired genetic damage. Once an abnormality in DNA has been induced and fixed in a germinal cell, it would be greatly amplified during future proliferation. These cells would commit suicide when injured for replacement by healthy cells, rather than undertake DNA repair. In fact they show very slow repair of cellular damage. Thus the high sensitivity of undifferentiated neural cells to the lethal effect of radiation may constitute a biological defense mechanism. (author) 69 refs.

  7. Trimetazidine protects against hypoxia-reperfusion-induced cardiomyocyte apoptosis by increasing microRNA-21 expression

    Yang, Qiong; Yang, Kan; Li, An-Ying

    2015-01-01

    Myocardial tissue injury caused by ischemia and hypoxia is a major cause of fatal diseases, including coronary atherosclerosis resulting from myocardial infarction and stroke. Trimetazidine (TMZ), as an anti-ischemic and antioxidant agent, has been demonstrated to preventing ischemia/reperfusion-induced cardiomyocyte apoptosis. However, the anti-apoptosis mechanism of TMZ has not been fully elucidated. The present study demonstrated that miR-21 involved trimetazidine-induced anti-apoptosis du...

  8. LR-90 prevents methylglyoxal-induced oxidative stress and apoptosis in human endothelial cells

    Figarola, James L.; Singhal, Jyotsana; Rahbar, Samuel; Awasthi, Sanjay; SINGHAL, SHARAD S.

    2014-01-01

    Methylglyoxal (MGO) is a highly reactive dicarbonyl compound known to induce cellular injury and cytoxicity, including apoptosis in vascular cells. Vascular endothelial cell apoptosis has been implicated in the pathophysiology and progression of atherosclerosis. We investigated whether the advanced glycation end-product inhibitor LR-90 could prevent MGO-induced apoptosis in human umbilical vascular endothelial cells (HUVECs). HUVECs were pre-treated with LR-90 and then stimulated with MGO. Ce...

  9. Rapid dissolution of ZnO nanocrystals in acidic cancer microenvironment leading to preferential apoptosis

    Sasidharan, Abhilash; Chandran, Parwathy; Menon, Deepthy; Raman, Sreerekha; Nair, Shantikumar; Koyakutty, Manzoor

    2011-09-01

    The microenvironment of cancer plays a very critical role in the survival, proliferation and drug resistance of solid tumors. Here, we report an interesting, acidic cancer microenvironment-mediated dissolution-induced preferential toxicity of ZnO nanocrystals (NCs) against cancer cells while leaving primary cells unaffected. Irrespective of the size-scale (5 and 200 nm) and surface chemistry differences (silica, starch or polyethylene glycol coating), ZnO NCs exhibited multiple stress mechanisms against cancer cell lines (IC50 ~150 μM) while normal human primary cells (human dermal fibroblast, lymphocytes, human umbilical vein endothelial cells) remain less affected. Flow cytometry and confocal microscopy studies revealed that ZnO NCs undergo rapid preferential dissolution in acidic (pH ~5-6) cancer microenvironment causing elevated ROS stress, mitochondrial superoxide formation, depolarization of mitochondrial membrane, and cell cycle arrest at S/G2 phase leading to apoptosis. In effect, by elucidating the unique toxicity mechanism of ZnO NCs, we show that ZnO NCs can destabilize cancer cells by utilizing its own hostile acidic microenvironment, which is otherwise critical for its survival.The microenvironment of cancer plays a very critical role in the survival, proliferation and drug resistance of solid tumors. Here, we report an interesting, acidic cancer microenvironment-mediated dissolution-induced preferential toxicity of ZnO nanocrystals (NCs) against cancer cells while leaving primary cells unaffected. Irrespective of the size-scale (5 and 200 nm) and surface chemistry differences (silica, starch or polyethylene glycol coating), ZnO NCs exhibited multiple stress mechanisms against cancer cell lines (IC50 ~150 μM) while normal human primary cells (human dermal fibroblast, lymphocytes, human umbilical vein endothelial cells) remain less affected. Flow cytometry and confocal microscopy studies revealed that ZnO NCs undergo rapid preferential dissolution in

  10. Trimetazidine protects against smoking-induced left ventricular remodeling via attenuating oxidative stress, apoptosis, and inflammation.

    Xiang Zhou

    Full Text Available Trimetazidine, a piperazine derivative used as an anti-anginal agent, improves myocardial glucose utilization through inhibition of fatty acid metabolism. The present study was designed to investigate whether trimetazidine has the protective effects against smoking-induced left ventricular remodeling in rats. In this study, Wistar rats were randomly divided into 3 groups: smoking group (exposed to cigarette smoke, trimetazidine group (exposed to cigarette smoke and treated with trimetazidine, and control group. The echocardiographic and morphometric data indicated that trimetazidine has protective effects against smoking-induced left ventricular remodeling. Oxidative stress was evaluated by detecting malondialdehyde, superoxide dismutase, and glutathione peroxidase in the supernatant of left ventricular tissue. Cardiomyocyte apoptotic rate was determined by flow cytometry with Annexin V/PI staining. Gene expression and serum levels of inflammatory markers, including interleukin-1β, interleukin-6, and tumor necrosis factor-α, were deteced by quantitative real-time PCR and enzyme-linked immunosorbent assay. Our results suggested that trimetazidine could significantly reduce smoking-induced oxidative stress, apoptosis, and inflammation. In conclusion, our study demonstrates that trimetazidine protects against smoking-induced left ventricular remodeling via attenuating oxidative stress, apoptosis, and inflammation.

  11. T cells cooperate with palmitic acid in induction of beta cell apoptosis

    Miljković Djordje

    2009-05-01

    Full Text Available Abstract Background Diabetes is characterized by progressive failure of insulin producing beta cells. It is well known that both saturated fatty acids and various products of immune cells can contribute to the reduction of beta cell viability and functionality during diabetes pathogenesis. However, their joint action on beta cells has not been investigated, so far. Therefore, we explored the possibility that leukocytes and saturated fatty acids cooperate in beta cell destruction. Results Rat pancreatic islets or insulinoma cells (RIN were co-cultivated with concanavalin A (ConA-stimulated rat lymph node cells (LNC, or they were treated with cell-free supernatants (Sn obtained from ConA-stimulated spleen cells or from activated CD3+ cells, in the absence or presence of palmitic acid (PA. ConA-stimulated LNC or Sn and PA cooperated in inducing caspase-3-dependent RIN cell apoptosis. The observed effect of PA and Sn on RIN cell viability was mediated by p38 mitogen-activated protein kinase (MAPK-signaling and was achieved through auto-destructive nitric oxide (NO production. The cooperative effect of Sn was mimicked with the combination of interleukin-1β, interleukin-2, interleukin-6, interleukin-17, interferon-γ and tumor necrosis factor-α. Conclusion These results imply that stimulated T cells produce cytokines that cooperate with saturated free fatty acids in beta cell destruction during diabetes pathogenesis.

  12. Ad-IRF-1 Induces Apoptosis in Esophageal Adenocarcinoma

    Gregory A. Watson

    2006-01-01

    Full Text Available The nuclear transcription factor interferon regulatory factor-1 (IRF-1 is a putative tumor suppressor, but the expression and function of IRF-1 in esophageal adenocarcinoma (EA remain unknown. We hypothesized that IRF-1 expression was reduced or lost in EA and that restoration of IRF-1 would result in the apoptosis of EA cells in vitro and the inhibition of tumor growth in vivo. Three EA cell lines were used to examine IRF-1 expression, IFN-γ responsiveness, and the effects of IRF-1 overexpression using a recombinant adenoviral vector (Ad-IRF-1. All three EA cell lines produced IRF-1 protein following IFN-γ stimulation, although IFN-γ did not induce cell death. In contrast, Ad-IRF-1 infection resulted in high levels of IRF-1 protein and triggered apoptosis in all three EA cell lines. Potential mechanisms for the differential response to IFN-γ versus Ad-IRF-1-such as modulation of c-Met or extracellular regulated kinase signaling, or altered expression of IRF-2, Fas, or survivin-were investigated, but none of these mechanisms can account for this observation. In vivo administration of IRF-1 in a murine model of EA modestly inhibited tumor growth, but did not lead to tumor regression. Strategies aimed at increasing or restoring IRF-1 expression may have therapeutic benefits in EA.

  13. PDT-induced apoptosis in arterial smooth muscles cells

    Nyamekye, Isaac; Renick, R.; Gilbert, C.; McEwan, Jean R.; Evan, G.; Bishop, Christopher C. R.; Bown, Stephen G.

    1995-03-01

    PDT kills smooth muscle cells (SMC) in vivo and thus prevents intimal hyperplasia after angioplasty. It causes little inflammation and structural integrity of the artery is not compromised. We have studied the process of the SMC death in vitro. Cultured rat SMC (cell line sv40 ATCC) were sensitized with aluminum disulphonated phthalocyanine (AlS2Pc), and then irradiated with 675 nm laser light (2.5 J/cm2). Controls were studied using only sensitizer or laser for treatment. The cells were incubated and the dying process observed with a time lapse video and microscope system. PDT caused a characteristic pattern of death. Cells lost contact with neighbors, shrank, and showed hyperactivity and membrane ruffling. The cells imploded into active and condensed membrane bound vesicles which were terminally reduced to residual bodies. These are the morphological changes of apoptosis. The control cells which were given AlS2Pc alone or laser alone showed no death. PDT induced cultured arterial SMC death by apoptosis rather than necrosis. An apoptotic mechanism of cell death in vivo would explain the relative lack of inflammation and local tissue destruction in the face of massive death.

  14. CIRRHOSIS INDUCES APOPTOSIS IN RENAL TISSUE THROUGH INTRACELLULAR OXIDATIVE STRESS

    Keli Cristina Simões da SILVEIRA

    2015-03-01

    Full Text Available Background Renal failure is a frequent and serious complication in patients with decompensated cirrhosis. Objectives We aimed to evaluate the renal oxidative stress, cell damage and impaired cell function in animal model of cirrhosis. Methods Secondary biliary cirrhosis was induced in rats by ligation of the common bile duct. We measured TBARS, ROS and mitochondrial membrane potential in kidney as markers of oxidative stress, and activities of the antioxidant enzymes. Relative cell viability was determined by trypan blue dye-exclusion assay. Annexin V-PE was used with a vital dye, 7-AAD, to distinguish apoptotic from necrotic cells and comet assay was used for determined DNA integrity in single cells. Results In bile duct ligation animals there was significant increase in the kidney lipoperoxidation and an increase of the level of intracellular ROS. There was too an increase in the activity of all antioxidant enzymes evaluated in the kidney. The percentage viability was above 90% in the control group and in bile duct ligation was 64.66% and the dominant cell death type was apoptosis. DNA damage was observed in the bile duct ligation. There was a decreased in the mitochondrial membrane potential from 71.40% ± 6.35% to 34.48% ± 11.40% in bile duct ligation. Conclusions These results indicate that intracellular increase of ROS cause damage in the DNA and apoptosis getting worse the renal function in cirrhosis.

  15. Endonucleases induced TRAIL-insensitive apoptosis in ovarian carcinoma cells

    TRAIL induced apoptosis of tumor cells is currently entering phase II clinical settings, despite the fact that not all tumor types are sensitive to TRAIL. TRAIL resistance in ovarian carcinomas can be caused by a blockade upstream of the caspase 3 signaling cascade. We explored the ability of restriction endonucleases to directly digest DNA in vivo, thereby circumventing the caspase cascade. For this purpose, we delivered enzymatically active endonucleases via the cationic amphiphilic lipid SAINT-18®:DOPE to both TRAIL-sensitive and insensitive ovarian carcinoma cells (OVCAR and SKOV-3, respectively). Functional nuclear localization after delivery of various endonucleases (BfiI, PvuII and NucA) was indicated by confocal microscopy and genomic cleavage analysis. For PvuII, analysis of mitochondrial damage demonstrated extensive apoptosis both in SKOV-3 and OVCAR. This study clearly demonstrates that cellular delivery of restriction endonucleases holds promise to serve as a novel therapeutic tool for the treatment of resistant ovarian carcinomas.

  16. An Apoptosis-inducing Isoform of Neu Differentiation Factor (NDF) Identified Using a Novel Screen for Dominant, Apoptosis-inducing Genes

    Grimm, Stefan; Leder, Philip

    1997-01-01

    Apoptosis is a genetically programmed series of events that results in cell death. As a consequence, it is difficult to identify dominant genes that play a role in this process using genetic selections in conventional cell culture systems. Accordingly, we have established an efficient expression screen to isolate dominant, apoptosis-inducing genes. The assay is based on the apoptotic morphology induced in the human kidney cell line 293 after transient transfection of small plasmid pools from ...

  17. Tumor Necrosis Factor-related Apoptosis Ligand Induces Apoptosis in Prostate Cancer PC-3M Cell Line

    CHEN Zhohui; WANG Huafang; GU Longjie; YE Zhewei; XIAO Yajun

    2005-01-01

    To study the effect of tumor necrosis factor-related apoptosis inducing ligand (TRAIL)on PC-3M cell line, PC-3M cell line was incubated with gradient concentrations of TRAIL for 4-24h. Annixin-Ⅴ fluorescence staining and TUNEL method were employed to detect the apoptosis of PC-3M cells. The morphology of apoptotic PC-3M cells was observed by electron microscopy. The relationship between TRAIL concentrations and the percentage of apoptotic cells was evaluated by flow cytometry. The proliferation inhibitory ratio was calculated by using MTT colorimetry. Our results showed that apoptosis of PC-3M cells could be induced by treatment with TRAIL for at most 4 h. The results of flow cytometry and MTT colorimetry demonstrated a time- and concentration-dependent relationship between cell apoptosis rate and TRAIL concentration. It is concluded that apoptosis of PC-3M cells can be induced by TRAIL. Because of the selective killing effect of TRAIL on tumor ceils, it may become a potential alternative for the treatment of advanced prostate cancer.

  18. N-acetylcholinesterase-induced apoptosis in Alzheimer's disease.

    Debra Toiber

    Full Text Available BACKGROUND: Alzheimer's disease (AD involves loss of cholinergic neurons and Tau protein hyper-phosphorylation. Here, we report that overexpression of an N-terminally extended "synaptic" acetylcholinesterase variant, N-AChE-S is causally involved in both these phenomena. METHODOLOGY AND PRINCIPAL FINDINGS: In transfected primary brain cultures, N-AChE-S induced cell death, morphological impairments and caspase 3 activation. Rapid internalization of fluorescently labeled fasciculin-2 to N-AChE-S transfected cells indicated membranal localization. In cultured cell lines, N-AChE-S transfection activated the Tau kinase GSK3, induced Tau hyper-phosphorylation and caused apoptosis. N-AChE-S-induced cell death was suppressible by inhibiting GSK3 or caspases, by enforced overexpression of the anti-apoptotic Bcl2 proteins, or by AChE inhibition or silencing. Moreover, inherent N-AChE-S was upregulated by stressors inducing protein misfolding and calcium imbalances, both characteristic of AD; and in cortical tissues from AD patients, N-AChE-S overexpression coincides with Tau hyper-phosphorylation. CONCLUSIONS: Together, these findings attribute an apoptogenic role to N-AChE-S and outline a potential value to AChE inhibitor therapeutics in early AD.

  19. Characterization of chlorpyrifos-induced apoptosis in placental cells

    The mechanism by which chlorpyrifos exerts its toxicity in fetal and perinatal animals has yet to be elucidated. Since the placenta is responsible for transport of nutrients and is a major supplier hormone to the fetus, exposure to xenobiotics that alter the function or viability of placenta cells could ostensibly alter the development of the fetus. In this study, JAR cells were used to determine if CPF and the metabolites 3,5,6-trichloro-2-pyridinol (TCP) and chlorpyrifos-oxon (CPO) are toxic to the placenta. Our results indicate that chlorpyrifos (CPF), and its metabolite chlorpyrifos-oxon (CPO) caused a dose-dependent reduction in cellular viability with CPF being more toxic than its metabolites. Chlorpyrifos-induced toxicity was characterized by the loss of mitochondrial potential, the appearance of nuclear condensation and fragmentation, down-regulation of Bcl-2 as well as up-regulation of TNFα and FAS mRNA. Pharmacological inhibition of FAS, nicotinic and TNF-α receptors did not attenuate CPF-induced toxicity. Atropine exhibited minimal ability to reverse toxicity. Furthermore, signal transduction inhibitors PD98059, SP600125, LY294002 and U0126 failed to attenuate toxicity; however, SB202190 (inhibitor of p38α and p38ss MAPK) sensitized cells to CPF-induced toxicity. Pan-caspase inhibitor Q-VD-OPh produced a slight but significant reversal of CPF-induced toxicity indicating that the major caspase pathways are not integral to CPF-induced toxicity. Taken collectively, these results suggest that chlorpyrifos induces apoptosis in placental cells through pathways not dependent on FAS/TNF signaling, activation of caspases or inhibition of cholinesterase. In addition, our data further indicates that activation of p38 MAPK is integral to the protection cells against CPF-induced injury

  20. Bitter apricot essential oil induces apoptosis of human HaCaT keratinocytes.

    Li, Keyou; Yang, Wenhua; Li, Zhe; Jia, Wangwang; Li, Jiazhou; Zhang, Pengfei; Xiao, Tiancun

    2016-05-01

    Psoriasis is a chronic skin disease that affects approximately 2% of the world's population. Conventional therapeutic approaches are not effective or necessarily safe for treating symptoms due to the serious side effects and resistance to currently prescribed drugs. Traditionally, in oriental medicine, apricot seed (Semen Armeniacae amarum) is used to treat skin diseases. However, the underlying mechanism of action has not been systematically elucidated. In the present study, the anti-proliferative effect of bitter apricot essential oil (BAEO) on cultured HaCaT cells was evaluated and the mechanism of action investigated. BAEO was isolated by hydrodistillation, and gas chromatography-mass spectrometry (GC-MS) analysis identified benzaldehyde (75.35%), benzoic acid (6.21%) and mandelonitrile (5.38%). HaCaT cell growth, measured by sulforhodamine B assay (SRB), was inhibited by BAEO with an IC50 value of 142.45 μg/ml. Apoptosis of HaCaT cells treated with BAEO was detected by cell cycle, flow cytometry, and western blot analyses. These measurements revealed G0/G1 cell cycle arrest, elevated numbers of early and late stage apoptotic cells, and caspases-3/8/9 and PARP activation. Z-VAD-FMK, a broad-spectrum caspase inhibitor, attenuated BAEO-induced apoptosis. Also, increased Bax and decreased Bcl-2 levels suggest that BAEO-induced apoptosis is mediated through both death receptor and mitochondrial pathways. Moreover, reduced Rel/NF-κB levels suggest that BAEO-mediated apoptosis is also associated with inhibition of the NF-κB pathway. These data suggest that BAEO is a naturally occurring material that functions as a potent pro-apoptotic factor for human keratinocytes. Thus, it is a promising candidate to treat psoriasis. PMID:26971222

  1. White tea extract induces apoptosis in non-small cell lung cancer cells: the role of peroxisome proliferator-activated receptor-{gamma} and 15-lipoxygenases.

    Mao, Jenny T; Nie, Wen-Xian; Tsu, I-Hsien; Jin, Yu-Sheng; Rao, Jian Yu; Lu, Qing-Yi; Zhang, Zuo-Feng; Go, Vay Liang W; Serio, Kenneth J

    2010-09-01

    Emerging preclinical data suggests that tea possess anticarcinogenic and antimutagenic properties. We therefore hypothesize that white tea extract (WTE) is capable of favorably modulating apoptosis, a mechanism associated with lung tumorigenesis. We examined the effects of physiologically relevant doses of WTE on the induction of apoptosis in non-small cell lung cancer cell lines A549 (adenocarcinoma) and H520 (squamous cell carcinoma) cells. We further characterized the molecular mechanisms responsible for WTE-induced apoptosis, including the induction of peroxisome proliferator-activated receptor-gamma (PPAR-gamma) and the 15-lipoxygenase (15-LOX) signaling pathways. We found that WTE was effective in inducing apoptosis in both A549 and H520 cells, and inhibition of PPAR-gamma with GW9662 partially reversed WTE-induced apoptosis. We further show that WTE increased PPAR-gamma activation and mRNA expression, concomitantly increased 15(S)-hydroxy-eicosatetraenoic acid release, and upregulated 15-LOX-1 and 15-LOX-2 mRNA expression by A549 cells. Inhibition of 15-LOX with nordihydroguaiaretic acid (NGDA), as well as caffeic acid, abrogated WTE-induced PPAR-gamma activation and upregulation of PPAR-gamma mRNA expression in A549 cells. WTE also induced cyclin-dependent kinase inhibitor 1A mRNA expression and activated caspase-3. Inhibition of caspase-3 abrogated WTE-induced apoptosis. Our findings indicate that WTE is capable of inducing apoptosis in non-small cell lung cancer cell lines. The induction of apoptosis seems to be mediated, in part, through the upregulation of the PPAR-gamma and 15-LOX signaling pathways, with enhanced activation of caspase-3. Our findings support the future investigation of WTE as an antineoplastic and chemopreventive agent for lung cancer. PMID:20668019

  2. Combined Treatment With Peroxisome Proliferator-Activated Receptor (PPAR) Gamma Ligands and Gamma Radiation Induces Apoptosis by PPARγ-Independent Up-Regulation of Reactive Oxygen Species-Induced Deoxyribonucleic Acid Damage Signals in Non-Small Cell Lung Cancer Cells

    Han, Eun Jong; Im, Chang-Nim; Park, Seon Hwa [Division of Radiation Cancer Research, Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of); Moon, Eun-Yi [Department of Bioscience and Biotechnology, Sejong University, Seoul (Korea, Republic of); Hong, Sung Hee, E-mail: gobrian@kcch.re.kr [Division of Radiation Cancer Research, Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of)

    2013-04-01

    Purpose: To investigate possible radiosensitizing activities of the well-known peroxisome proliferator-activated receptor (PPAR)γ ligand ciglitazone and novel PPARγ ligands CAY10415 and CAY10506 in non-small cell lung cancer (NSCLC) cells. Methods and Materials: Radiosensitivity was assessed using a clonogenic cell survival assay. To investigate the mechanism underlying PPARγ ligand-induced radiosensitization, the subdiploid cellular DNA fraction was analyzed by flow cytometry. Activation of the caspase pathway by combined PPARγ ligands and γ-radiation treatment was detected by immunoblot analysis. Reactive oxygen species (ROS) were measured using 2,7-dichlorodihydrofluorescein diacetate and flow cytometry. Results: The 3 PPARγ ligands induced cell death and ROS generation in a PPARγ-independent manner, enhanced γ-radiation–induced apoptosis and caspase-3–mediated poly (ADP-ribose) polymerase (PARP) cleavage in vitro. The combined PPARγ ligand/γ-radiation treatment triggered caspase-8 activation, and this initiator caspase played an important role in the combination-induced apoptosis. Peroxisome proliferator-activated receptor-γ ligands may enhance the γ-radiation-induced DNA damage response, possibly by increasing γ-H2AX expression. Moreover, the combination treatment significantly increased ROS generation, and the ROS scavenger N-acetylcysteine inhibited the combined treatment-induced ROS generation and apoptotic cell death. Conclusions: Taken together, these results indicated that the combined treatment of PPARγ ligands and γ-radiation synergistically induced DNA damage and apoptosis, which was regulated by ROS.

  3. Zinc protects human kidney cells from depleted uranium-induced apoptosis.

    Hao, Yuhui; Ren, Jiong; Liu, Cong; Li, Hong; Liu, Jing; Yang, Zhangyou; Li, Rong; Su, Yongping

    2014-03-01

    Depleted uranium (DU) is a weak radioactive heavy metal, and zinc (Zn) is an effective antidote to heavy metal poisoning. However, the effect of Zn on DU-induced cytotoxicity and apoptosis is not completely understood. The purpose of this study was to evaluate the effect of Zn on DU-induced cell apoptosis in human kidney cells (HK-2) and explore its molecular mechanism. Pre-treatment with Zn significantly inhibited DU-induced apoptosis. It reduced the formation of reactive oxygen species in the cells, increased the catalase (CAT) and glutathione (GSH) concentrations, suppressed the DU-induced soluble Fas receptor (sFasR) and soluble Fas ligand (sFasL) overexpression, suppressed the release of cytochrome c and apoptosis inhibitor factor (AIF) from mitochondria to cytoplasm, inhibited the activation of caspase-9, caspase-8 and caspase-3, and induced metallothionein (MT) expression. Furthermore, exogenous MT effectively inhibited DU-induced cell apoptosis. In conclusion, mitochondrial and FasR-mediated apoptosis pathways contribute to DU-induced apoptosis in HK-2 cells. Through independent mechanisms, such as indirect antioxidant effects, inhibition of the activation of caspase-9, caspase-8 and caspase-3, and induction of MT expression, Zn inhibits DU-induced apoptosis. PMID:24330236

  4. Evidence that tumor necrosis factor-related apoptosis inducing ligand (TRAIL) inhibits angiogenesis by inducing vascular endothelial cell apoptosis

    Tumor necrosis factor (TNF) and its related ligands TNF-related apoptosis inducing ligand (TRAIL) and Fas ligand (FasL) play roles in the regulation of vascular responses, but their effect on the formation of new blood vessels (angiogenesis) is unclear. Therefore, we have examined the effects of these ligands on angiogenesis modeled with primary cultures of human umbilical vein endothelial cells (HUVEC). To examine angiogenesis in the context of the central nervous system, we have also modeled cerebral angiogenesis with the human brain endothelial cell line hCMEC/D3. Parameters studied were bromodeoxyuridine (BrdU) incorporation and cell number (MTT) assay (to assess endothelial proliferation), scratch assay (migration) and networks on Matrigel (tube formation). In our hands, neither TRAIL nor FasL (1, 10, and 100 ng/ml) had an effect on parameters of angiogenesis in the HUVEC model. In hCMEC/D3 cells by contrast, TRAIL inhibited all parameters (10-100 ng/ml, 24 h). This was due to apoptosis, since its action was blocked by the pan-caspase inhibitor zVADfmk (5 x 10-5 mol/l) and TRAIL increased caspase-3 activity 1 h after application. However FasL (100 ng/ml) increased BrdU uptake without other effects. We conclude that TRAIL has different effects on in vitro angiogenesis depending on which model is used, but that FasL is generally ineffective when applied in vitro. The data suggest that TRAIL primarily influences angiogenesis by the induction of vascular endothelial apoptosis, leading to vessel regression.

  5. 5-Ene-4-thiazolidinones induce apoptosis in mammalian leukemia cells.

    Senkiv, Julia; Finiuk, Nataliya; Kaminskyy, Danylo; Havrylyuk, Dmytro; Wojtyra, Magdalena; Kril, Iryna; Gzella, Andrzej; Stoika, Rostyslav; Lesyk, Roman

    2016-07-19

    The article presents the synthesis of 5-ene-4-thiazolidinone derivatives with pyrazole core linked by enamine group. The structure and purity of compounds were confirmed by analytical and spectral data including X-ray analysis. Target compounds were screened for their anticancer activity and selective antileukemic action was confirmed. 5-[5-(2-Hydroxyphenyl)-3-phenyl-4,5-dihydropyrazol-1-ylmethylene]-3-(3-acetoxyphenyl)-2-thioxothiazolidin-4-one (compound 1) was selected as most active agent against HL-60 and HL-60/ADR cell lines; IC50 = 118 nM/HL-60 with low toxicity towards pseudonormal cells. The mitochondria-depended apoptosis was identified as the main mode of 1 action. Moreover compound's effect induces G0/G1 arrest of the treated cells and causes inhibition of cell division and is related with activation of ROS production. PMID:27089210

  6. Phosphatidylcholine induces apoptosis of 3T3-L1 adipocytes

    Li Hailan

    2011-12-01

    Full Text Available Abstract Background Phosphatidylcholine (PPC formulation is used for lipolytic injection, even though its mechanism of action is not well understood. Methods The viability of 3T3-L1 pre-adipocytes and differentiated 3T3-L1 cells was measured after treatment of PPC alone, its vehicle sodium deoxycholate (SD, and a PPC formulation. Western blot analysis was performed to examine PPC-induced signaling pathways. Results PPC, SD, and PPC formulation significantly decreased 3T3-L1 cell viability in a concentration-dependent manner. PPC alone was not cytotoxic to CCD-25Sk human fibroblasts at concentrations Conclusions PPC results in apoptosis of 3T3-L1 cells.

  7. 1,10-Phenanthroline promotes copper complexes into tumor cells and induces apoptosis by inhibiting the proteasome activity.

    Zhang, Zhen; Bi, Caifeng; Schmitt, Sara M; Fan, Yuhua; Dong, Lili; Zuo, Jian; Dou, Q Ping

    2012-12-01

    Indole-3-acetic acid and indole-3-propionic acid, two potent natural plant growth hormones, have attracted attention as promising prodrugs in cancer therapy. Copper is known to be a cofactor essential for tumor angiogenesis. We have previously reported that taurine, L-glutamine, and quinoline-2-carboxaldehyde Schiff base copper complexes inhibit cell proliferation and proteasome activity in human cancer cells. In the current study, we synthesized two types of copper complexes, dinuclear complexes and ternary complexes, to investigate whether a certain structure could easily carry copper into cancer cells and consequently inhibit tumor proteasome activity and induce apoptosis. We observed that ternary complexes binding with 1,10-phenanthroline are more potent proteasome inhibitors and apoptosis inducers than dinuclear complexes in PC-3 human prostate cancer cells. Furthermore, the ternary complexes potently inhibit proteasome activity before induction of apoptosis in MDA-MB-231 human breast cancer cells, but not in nontumorigenic MCF-10A cells. Our results suggest that copper complexes binding with 1,10-phenanthroline as the third ligand could serve as potent, selective proteasome inhibitors and apoptosis inducers in tumor cells, and that the ternary complexes may be good potential anticancer drugs. PMID:23053530

  8. Induction of apoptosis and change of bcl—2 expression in macrophage Ana—1 cells by all—trans retinoic acid

    YINDELING; XIUHAIREN; 等

    1996-01-01

    Macrophage cells play an important role in the initiation and regulation of the immune response.All-trans retinoic acid (ATRA) and its natural and synthetic analogs (retinoids)affect a large number of biological processes.Recently,retinoids have been shown promise in the therapy and prevention of various cancers.However,many interesting questions related to the activities of retinoids remain to be answered:(I) Molecular mechanisms by which retinoids exert their effects;(Ⅱ)why the clinical uses of retinoids give undesirable side effects of varying severity with a higher frequency of blood system symptoms;(Ⅲ)little is known for its impacts on macrophage cells etc.We set up this experiment,therefore,to examine the apoptosis of ATRA on macrophage Ana-1 cell line.Apoptosis of the cells was quantitated,after staining cells with propidium iodide(PI),by both accounting nuclear condensation and flow cytometry.When the cells were treated with ATRA at or higher than 1μM for more than 24h,significant amount of the apoptotic cells was observed.Induction of apoptosis of Ana-1 cells by ATRA was in time-and dose-dependent manners,exhibiting the similar pattern as the apoptosis induced by actinomycin D (ACTD).ATRA treatment of Ana-1 cells also caused the changes of the mRNA levels of apoptosis-associated gene bcl-2,as detected by Northern blot analysis.The temporal changes of bcl-2 expression by ATRA was also parallel to that by ACTD.In conclusion,ATRA can induce apoptosis in macrophage cells,which may be helpful in understanding of immunological functions retinoids.

  9. Apoptosis induced in vivo by photodynamic therapy in normal brain and intracranial tumour tissue.

    Lilge, L; Portnoy, M; Wilson, B C

    2000-10-01

    The apoptotic response of normal brain and intracranial VX2 tumour following photodynamic therapy (PDT) mediated by 5 different photosensitizers (Photofrin, 5-aminolaevulinic acid (ALA)-induced protoporphyrin IX (PpIX), chloroaluminium phthalocyanine (AlCIPc), Tin Ethyl Etiopurpurin (SnET(2)), and meta -tetra(hydroxyphenyl)chlorin (m THPC)) was evaluated following a previous analysis which investigated the necrotic tissue response to PDT at 24 h post treatment. Free DNA ends, produced by internucleosomal DNA cleavage in apoptotic cells, were stained using a TUNEL (terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick-end labelling) assay. Confocal laser scanning microscopy (CLSM) was used to quantify the local incidence of apoptosis and determine its spatial distribution throughout the brain. The incidence of apoptosis was confirmed by histopathology, which demonstrated cell shrinkage, pyknosis and karyorrhexis. At 24 h post PDT, AlClPc did not cause any detectable apoptosis, while the other photosensitizers produced varying numbers of apoptotic cells near the region of coagulative necrosis. The apoptotic response did not appear to be related to photosensitizer dose. These results suggest that at this time point, a minimal and fairly localized apoptotic effect is produced in brain tissues, the extent of which depends largely on the particular photosensitizer. PMID:10993661

  10. Stat1 activation attenuates IL-6 induced Stat3 activity but does not alter apoptosis sensitivity in multiple myeloma

    Dimberg Lina Y

    2012-07-01

    Full Text Available Abstract Background Multiple myeloma (MM is at present an incurable malignancy, characterized by apoptosis-resistant tumor cells. Interferon (IFN treatment sensitizes MM cells to Fas-induced apoptosis and is associated with an increased activation of Signal transducer and activator of transcription (Stat1. The role of Stat1 in MM has not been elucidated, but Stat1 has in several studies been ascribed a pro-apoptotic role. Conversely, IL-6 induction of Stat3 is known to confer resistance to apoptosis in MM. Methods To delineate the role of Stat1 in IFN mediated sensitization to apoptosis, sub-lines of the U-266-1970 MM cell line with a stable expression of the active mutant Stat1C were utilized. The influence of Stat1C constitutive transcriptional activation on endogenous Stat3 expression and activation, and the expression of apoptosis-related genes were analyzed. To determine whether Stat1 alone would be an important determinant in sensitizing MM cells to apoptosis, the U-266-1970-Stat1C cell line and control cells were exposed to high throughput compound screening (HTS. Results To explore the role of Stat1 in IFN mediated apoptosis sensitization of MM, we established sublines of the MM cell line U-266-1970 constitutively expressing the active mutant Stat1C. We found that constitutive nuclear localization and transcriptional activity of Stat1 was associated with an attenuation of IL-6-induced Stat3 activation and up-regulation of mRNA for the pro-apoptotic Bcl-2 protein family genes Harakiri, the short form of Mcl-1 and Noxa. However, Stat1 activation alone was not sufficient to sensitize cells to Fas-induced apoptosis. In a screening of > 3000 compounds including bortezomib, dexamethasone, etoposide, suberoylanilide hydroxamic acid (SAHA, geldanamycin (17-AAG, doxorubicin and thalidomide, we found that the drug response and IC50 in cells constitutively expressing active Stat1 was mainly unaltered. Conclusion We conclude that Stat1 alters IL-6

  11. Game and players: mitochondrial apoptosis and the therapeutic potential of ursodeoxycholic acid.

    Solá, Susana; Aranha, Márcia M; Steer, Clifford J; Rodrigues, Cecília M P

    2007-07-01

    Apoptosis represents a universal and exquisitely efficient cellular suicide pathway essential for a variety of normal biological processes ranging from embryonic development to ageing. In fact, tissue homeostasis is dependent on the perfect balance between positive and negative signals that determines the decision between life and death. Therefore, any imbalance can result in a wide range of pathologic disorders associated with unwanted apoptosis or cell growth. During the apoptotic process, the molecular players interact closely with each other in ways relevant to accelerate or interrupt the cellular death process. In addition, two major pathways of apoptosis activation have been recognized as the "intrinsic" mitochondrial pathway and the "extrinsic" death receptor pathway. Although these pathways act independently to initiate apoptosis, a delicate balance and cross-talk between the extrinsic and intrinsic pathways is thought to occur in many cell types. Interestingly, we have shown that ursodeoxycholic acid (UDCA), an endogenous hydrophilic bile acid, is a potent inhibitor of apoptosis by either stabilizing the mitochondrial membrane or modulating the expression of specific upstream targets. Herein, we review the main effectors involved in the death machinery, describe how they interact to regulate apoptosis, and discuss the main pathways that control cell death and survival. Further, we address multiple interesting targets as well as the potential application of UDCA as a therapeutic modality for apoptosis-related disorders. PMID:17489439

  12. Sodium Butyrate Induces Endoplasmic Reticulum Stress and Autophagy in Colorectal Cells: Implications for Apoptosis.

    Jintao Zhang

    Full Text Available Butyrate, a short-chain fatty acid derived from dietary fiber, inhibits proliferation and induces cell death in colorectal cancer cells. However, clinical trials have shown mixed results regarding the anti-tumor activities of butyrate. We have previously shown that sodium butyrate increases endoplasmic reticulum stress by altering intracellular calcium levels, a well-known autophagy trigger. Here, we investigated whether sodium butyrate-induced endoplasmic reticulum stress mediated autophagy, and whether there was crosstalk between autophagy and the sodium butyrate-induced apoptotic response in human colorectal cancer cells.Human colorectal cancer cell lines (HCT-116 and HT-29 were treated with sodium butyrate at concentrations ranging from 0.5-5mM. Cell proliferation was assessed using MTT tetrazolium salt formation. Autophagy induction was confirmed through a combination of Western blotting for associated proteins, acridine orange staining for acidic vesicles, detection of autolysosomes (MDC staining, and electron microscopy. Apoptosis was quantified by flow cytometry using standard annexinV/propidium iodide staining and by assessing PARP-1 cleavage by Western blot.Sodium butyrate suppressed colorectal cancer cell proliferation, induced autophagy, and resulted in apoptotic cell death. The induction of autophagy was supported by the accumulation of acidic vesicular organelles and autolysosomes, and the expression of autophagy-associated proteins, including microtubule-associated protein II light chain 3 (LC3-II, beclin-1, and autophagocytosis-associated protein (Atg3. The autophagy inhibitors 3-methyladenine (3-MA and chloroquine inhibited sodium butyrate induced autophagy. Furthermore, sodium butyrate treatment markedly enhanced the expression of endoplasmic reticulum stress-associated proteins, including BIP, CHOP, PDI, and IRE-1a. When endoplasmic reticulum stress was inhibited by pharmacological (cycloheximide and mithramycin and genetic

  13. Proteomic analysis of mechanisms of hypoxia-induced apoptosis in trophoblastic cells

    Shin-ichi Ishioka, Yoshiaki Ezaka, Kota Umemura, Takuhiro Hayashi, Toshiaki Endo, Tsuyoshi Saito

    2007-01-01

    Full Text Available Preeclampsia is often accompanied by hypoxia of the placenta and this condition induces apoptosis in trophoblastic cells. The aim of this study was to characterize global changes of apoptosis-related proteins induced by hypoxia in trophoblastic cells so as to clarify the mechanism of hypoxia-induced apoptosis by using the PoweBlot, an antibody-based Western array. Human choriocarcinoma cell line JAR was cultured for 24 hours under aerobic and hypoxic conditions. Hypoxia induced apoptosis accompanied by increased expression of Bcl-x, Caspase-3 and -9, Hsp70, PTEN, and Bag-1. Bad, pan-JNK/SAPK-1, Bcl-2, Bid, and Caspase-8 showed decreased expression. Hypoxia-induced apoptosis was increased with the transfection of a bag-1 antisense oligonucleotide. The bag-1 antisense oligonucleotide affected the expression of Bid, Bad, Bcl-2, JNK, and phosphorylated JNK, although expression of PTEN and Bcl-X did not change. Bag-1 may inhibit apoptosis by suppressing the expression of Bid and Bad. It may also enhance apoptosis by inhibiting the expression of Bcl-2 and by modulating phosphorylation of JNK. Both mitochondrial and stress-activated apoptosis pathways played important roles in the hypoxia induced cell death of trophoblastic cells. These findings will contribute to establish new approach to detect hypoxic stress of the placenta, which leads to preeclampsia and other hypoxia-related obstetrics complications.

  14. ROS-mediated lipopolysaccharide-induced apoptosis in INS-1 cells by modulation of Bcl-2 and Bax.

    DU, S-C; Ge, Q-M; Lin, N; Dong, Y; Su, Q

    2012-01-01

    Overproduction of reactive oxygen species (ROS) or exhaustion of antioxidants may cause oxidative stress which is a major factor of defective insulin secretion and increases apoptosis of pancreatic β-cells in diabetes. So there comes a consideration of whether antioxidant strategies can be used to protect deterioration of the β-cells. In this study, we explored the mechanism of oxidative stress mediated lipopolysaccharide (LPS) induced apoptosis in insulin secreting (INS-1) cells from a rat pancreatic β-cell line. ROS was monitored by using intracellular ROS capture dihydroethidium (DHE) and dihydrorhodamine123 (DHR123). Apoptosis rate was measured by flow cytometry (FCM). The pro-apoptotic gene Bax and anti-apoptotic gene Bcl-2 were analysed by Western blot and RT-PCR. The results demonstrate that LPS-stimulated INS-1 cells manifest intensified intracellular fluorescence in both dose- and time- dependent manners. Apoptosis rate of LPS stimulated INS-1 cells is significantly increased by FCM, with a significant increase in Bax/Bcl-2 ratio revealed by Western blot and RT-PCR. Furthermore, α-lipoic acid (α-LA) inhibits LPS-induced apoptosis, but can not restore the function of glucose stimulated insulin secretion (GSIS) in INS-1 cells. PMID:22455982

  15. Atorvastatin induces apoptosis by a caspase-9-dependent pathway: an in vitro study on activated rat hepatic stellate cells

    Aprigliano, Isabella; Dudas, Joszef; Ramadori, Giuliano; Saile, Bernhard

    2008-01-01

    Background Statins are shown to have cholesterol-independent properties such as anti-inflammation and immunomodulation. Activated hepatic stellate cells (HSCs) acquire the capacity to synthesize matrix proteins in damaged liver. We tested the hypothesis that atorvastatin may be capable of inducing apoptosis in HSCs. Methods Primary cultures of rat HSCs were exposed to atorvastatin, mevalonic acid and U0126. Quantification of living, apoptotic and necrotic HSCs was performed by flow cytometry ...

  16. The cyclooxygenase-2 pathway via the PGE2 EP2 receptor contributes to oligodendrocytes apoptosis in cuprizone-induced demyelination

    Palumbo, Sara; Toscano, Christopher D.; Parente, Laura; Weigert, Roberto; Bosetti, Francesca

    2011-01-01

    Cyclooxygenases (COX)-1 and -2 are key enzymes required for the conversion of arachidonic acid (AA) to eicosanoids, potent mediators of inflammation. In patients with multiple sclerosis (MS), COX-2 derived prostaglandins (PGs) are elevated in the cerebrospinal fluid and COX-2 is upregulated in demyelinating plaques. However, it is not known whether COX-2 activity contributes to oligodendrocyte death. In cuprizone-induced demyelination, oligodendrocyte apoptosis and a concomitant increase in t...

  17. Protection from Palmitate-Induced Mitochondrial DNA Damage Prevents from Mitochondrial Oxidative Stress, Mitochondrial Dysfunction, Apoptosis, and Impaired Insulin Signaling in Rat L6 Skeletal Muscle Cells

    Yuzefovych, Larysa V.; Solodushko, Viktoriya A.; Wilson, Glenn L.; Rachek, Lyudmila I.

    2011-01-01

    Saturated free fatty acids have been implicated in the increase of oxidative stress, mitochondrial dysfunction, apoptosis, and insulin resistance seen in type 2 diabetes. The purpose of this study was to determine whether palmitate-induced mitochondrial DNA (mtDNA) damage contributed to increased oxidative stress, mitochondrial dysfunction, apoptosis, impaired insulin signaling, and reduced glucose uptake in skeletal muscle cells. Adenoviral vectors were used to deliver the DNA repair enzyme ...

  18. 4-Hydroxybenzyl modification of the highly teratogenic retinoid, 4-[(1E)-2-(5,5,8,8-tetramethyl-5,6,7,8-tetrahydro-2-naphthalenyl)-1-propen-1-yl]benzoic acid (TTNPB), yields a compound that induces apoptosis in breast cancer cells and shows reduced teratogenicity.

    Anding, Allyson L; Nieves, Nirca J; Abzianidze, Victoria V; Collins, Michael D; Curley, Robert W; Clagett-Dame, Margaret

    2011-11-21

    Retinoids are a class of compounds with structural similarity to vitamin A. These compounds inhibit the proliferation of many cancer cell lines but have had limited medical application as they are often toxic at therapeutic levels. Efforts to synthesize retinoids with a greater therapeutic index have met with limited success. 4-[(1E)-2-(5,5,8,8-tetramethyl-5,6,7,8-tetrahydro-2-naphthalenyl)-1-propen-1-yl]benzoic acid (TTNPB) is one of the most biologically active all-trans-retinoic acid (atRA) analogues and is highly teratogenic. In this study, we show that modification of the TTNPB carboxyl group with an N-(4-hydroxyphenyl)amido (4HPTTNPB) or a 4-hydroxybenzyl (4HBTTNPB) group changes the activity of the compound in cell culture and in vivo. Unlike TTNPB, both compounds induce apoptosis in cancer cells and bind poorly to the retinoic acid receptors (RARs). Like the similarly modified all-trans-retinoic acid (atRA) analogues N-(4-hydroxyphenyl)retinamide (4-HPR/fenretinide) and 4-hydroxybenzylretinone (4-HBR), 4HBTTNPB is a potent activator of components of the ER stress pathway. The amide-linked analogue, 4HPTTNPB, is less toxic to developing embryos than the parent TTNPB, and most significantly, the 4-hydroxybenzyl-modified compound (4HBTTNPB) that cannot be hydrolyzed in vivo to the parent TTNPB compound is nearly devoid of teratogenic liability. PMID:21939267

  19. Minocycline protects the apoptosis of PC12 cells induced by 1-methyl-4-phenylpyridinium

    2005-01-01

    Objective: To explore the protective effect of minocycline on the apoptosis of cellular parkinsonism models induced by MPP+ . Methods: Using PC12 cells as the apoptotic model of dopaminergic neurons, MC and MPP+ were added into the culture medium of PC12 cells, and using MTT to assay the cell viability and metabolic state; The cells apoptosis was assayed by electrophoresis method and using flow cytometry FACS to assay the apoptosis ratio. Results: Added the MPP+ to get the concentration of 10μmol/L, the cellular parkinsonism model of apoptosis had been prepared. The pre-treatment of MC (100 μmol/L) could significantly increase the PC12 cell viability. The apoptosis ratio of MC + MPP+ group was significantly lower than that of MPP+ group, but was still significantly higher than that of control group. Conclusion: MC may protect the cell apoptosis induced by MPP+ to some extent.

  20. Curcumin induces apoptosis-independent death in oesophageal cancer cells.

    O'Sullivan-Coyne, G

    2012-01-31

    BACKGROUND: Oesophageal cancer incidence is increasing and survival rates remain extremely poor. Natural agents with potential for chemoprevention include the phytochemical curcumin (diferuloylmethane). We have examined the effects of curcumin on a panel of oesophageal cancer cell lines. METHODS: MTT (3-(4,5-dimethyldiazol-2-yl)-2,5 diphenyl tetrazolium bromide) assays and propidium iodide staining were used to assess viability and DNA content, respectively. Mitotic catastrophe (MC), apoptosis and autophagy were defined by both morphological criteria and markers such as MPM-2, caspase 3 cleavage and monodansylcadaverine (MDC) staining. Cyclin B and poly-ubiquitinated proteins were assessed by western blotting. RESULTS: Curcumin treatment reduces viability of all cell lines within 24 h of treatment in a 5-50 muM range. Cytotoxicity is associated with accumulation in G2\\/M cell-cycle phases and distinct chromatin morphology, consistent with MC. Caspase-3 activation was detected in two out of four cell lines, but was a minor event. The addition of a caspase inhibitor zVAD had a marginal or no effect on cell viability, indicating predominance of a non-apoptotic form of cell death. In two cell lines, features of both MC and autophagy were apparent. Curcumin-responsive cells were found to accumulate poly-ubiquitinated proteins and cyclin B, consistent with a disturbance of the ubiquitin-proteasome system. This effect on a key cell-cycle checkpoint regulator may be responsible for the mitotic disturbances and consequent cytotoxicity of this drug. CONCLUSION: Curcumin can induce cell death by a mechanism that is not reliant on apoptosis induction, and thus represents a promising anticancer agent for prevention and treatment of oesophageal cancer.

  1. Curcumin induces apoptosis-independent death in oesophageal cancer cells.

    O'Sullivan-Coyne, G

    2009-10-06

    Background:Oesophageal cancer incidence is increasing and survival rates remain extremely poor. Natural agents with potential for chemoprevention include the phytochemical curcumin (diferuloylmethane). We have examined the effects of curcumin on a panel of oesophageal cancer cell lines.Methods:MTT (3-(4,5-dimethyldiazol-2-yl)-2,5 diphenyl tetrazolium bromide) assays and propidium iodide staining were used to assess viability and DNA content, respectively. Mitotic catastrophe (MC), apoptosis and autophagy were defined by both morphological criteria and markers such as MPM-2, caspase 3 cleavage and monodansylcadaverine (MDC) staining. Cyclin B and poly-ubiquitinated proteins were assessed by western blotting.Results:Curcumin treatment reduces viability of all cell lines within 24 h of treatment in a 5-50 muM range. Cytotoxicity is associated with accumulation in G2\\/M cell-cycle phases and distinct chromatin morphology, consistent with MC. Caspase-3 activation was detected in two out of four cell lines, but was a minor event. The addition of a caspase inhibitor zVAD had a marginal or no effect on cell viability, indicating predominance of a non-apoptotic form of cell death. In two cell lines, features of both MC and autophagy were apparent. Curcumin-responsive cells were found to accumulate poly-ubiquitinated proteins and cyclin B, consistent with a disturbance of the ubiquitin-proteasome system. This effect on a key cell-cycle checkpoint regulator may be responsible for the mitotic disturbances and consequent cytotoxicity of this drug.Conclusion:Curcumin can induce cell death by a mechanism that is not reliant on apoptosis induction, and thus represents a promising anticancer agent for prevention and treatment of oesophageal cancer.British Journal of Cancer advance online publication, 6 October 2009; doi:10.1038\\/sj.bjc.6605308 www.bjcancer.com.

  2. Valproic Acid Induced Hyperammonaemic Encephalopathy

    Objective: To observe clinical and laboratory features of valproic acid-induced hyperammonaemic encephalopathy in patients taking valproic acid. Methods: Observational study was conducted at the Neurology Department, Dow University of Health Sciences, Civil Hospital, Karachi, from February 26, 2010 to March 20, 2011. Ten patients on valproic acid therapy of any age group with idiopathic or secondary epilepsy, who presented with encephalopathic symptoms, were registered and followed up during the study. Serum ammonia level, serum valproic acid level, liver function test, cerebrospinal fluid examination, electroencephalogram and brain imaging of all the patients were done. Other causes of encephalopathy were excluded after clinical and appropriate laboratory investigations. Microsoft Excel 2007 was used for statistical analysis. Results: Hyperammonaemia was found in all patients with encephalopathic symptoms. Rise in serum ammonia was independent of dose and serum level of valproic acid. Liver function was also found to be normal in 80% (n=8) of the patients. Valproic acid was withdrawn in all patients. Three (30%) patients improved only after the withdrawal of valproic acid. Six (60%) patients improved after L-Carnitine replacement, one (10%) after sodium benzoate. On followup, serum ammonia had reduced to normal in five (50%) patients and to more than half of the baseline level in two (20%) patients. Three (30%) patients were lost to followup after complete clinical improvement. Conclusion: Within therapeutic dose and serum levels, valproic acid can cause symptomatic hyperammonaemia resulting in encephalopathy. All patients taking valproic acid presenting with encephalopathic symptoms must be monitored for the condition. (author)

  3. DMPD: Pathogen-induced apoptosis of macrophages: a common end for different pathogenicstrategies. [Dynamic Macrophage Pathway CSML Database

    Full Text Available 11207583 Pathogen-induced apoptosis of macrophages: a common end for different pathogenicstrate...ml) Show Pathogen-induced apoptosis of macrophages: a common end for different pathogenicstrategies. PubmedI...D 11207583 Title Pathogen-induced apoptosis of macrophages: a common end for different pathogenicstrate

  4. p53-dependent apoptosis suppresses radiation-induced teratogenesis

    About half of human conceptions are estimated not to be implanted in the uterus, resulting in unrecognizable spontaneous abortions. Experimental studies with mice have established that irradiation during the preimplantation period of the embryo induces a high incidence of prenatal deaths but virtually no malformations. This suggests that some mechanism is screening out the damaged fetuses. In order to elucidate the mechanisms of tissue repair of radiation-induced teratogenic injury, we compared the incidences of radiation-induced malformations and abortions in p53 null (p53-/-) and wild-type (p53+/+) mice. After X-irradiation with 2 Gy on day 9.5 of gestation, p53-/- mice showed a 70% incidence of anomalies and a 7% incidence of deaths, whereas p53+/+ mice had a 20% incidence of anomalies and a 60% incidence of deaths. Similar results were obtained after irradiation on day 3.5 of gestation. This reciprocal relationship of radiosensitivity to anomalies and to embryonic or fetal lethality supports the notion that the p53 gene protects embryos and fetuses against the teratogenic effects of radiation by eliminating cells that have been badly damaged. In fact, after X-irradiation, the frequency of dying cells by apoptosis was greatly increased in tissues of the p53+/+ fetuses but not at all in those of the p53-/- fetuses. Mammals are protected from radiation-induced injury by two mechanisms, p53-dependent apoptotic tissue repair in addition to well known DNA repair. Therefore, there are threshold doses below which there is no induction of teratogenic and carcinogenic effects after exposure to low-level radiation. (author)

  5. Baicalein selectively induces apoptosis in activated lymphocytes and ameliorates concanavalin a-induced hepatitis in mice.

    Yan Zhang

    Full Text Available BACKGROUND: Insufficient apoptosis in activated lymphocytes contributes to the development of autoimmune hepatitis (AIH. Baicalein (BE, a flavonoid originally isolated from the root of Scutellaria baicalensis Georgi, possesses anti-inflammatory properties. However, whether BE can selectively induce apoptosis in activated lymphocytes and exert therapeutic effect on AIH has not been studied. METHODOLOGY/PRINCIPAL FINDINGS: The pro-apoptotic properties of BE were evaluated in vitro on different types of immune cells, and in vivo effects of BE were examined in a murine model of Concanavalin A (Con A-induced hepatitis. In vitro treatment with BE resulted in a higher increase in the level of apoptosis in Con A-stimulated murine splenocytes, Con A-stimulated CD3(+ splenocytes, lipopolysaccharide (LPS-stimulated CD19(+ splenocytes, and phorbol 12-myristate 13-acetate/ionomycin-stimulated Jurkat T cells, compared with that in unstimulated naïve ones. Murine bone marrow-derived dentritic cells, peritoneal macrophages, and RAW264.7 cells, either stimulated with LPS or unstimulated, were all insensitive to the BE-induced apoptosis. BE treatment also led to a loss of mitochondrial membrane potential, an increase of cytochrome c release from mitochondria to the cytosol, a decrease in the ratio of Bcl-2/Bax, and activation of caspase-9,-3 in Con A-stimulated CD3(+ splenocytes and LPS-stimulated CD19(+ splenocytes, while showing no impact on Fas/FasL expressions and caspase-8 activation. In vivo administration of BE alleviated Con A-induced liver injury, suppressed serum level of TNF-α and IFN-γ, and reduced liver infiltration of mononuclear cells (MNCs. Furthermore, BE treatment increased the incidences of apoptosis in liver-infiltrating MNCs and splenocytes, as well as in CD3(+ and CD19(+ splenocytes. When liver MNCs and splenocytes from BE-treated mice were cultured in vitro for 24 h, they exhibited marked increase in apoptosis compared to vehicle

  6. Helicobacter pylori enhances tumor necrosis factor-related apoptosis-inducing ligand-mediated apoptosis in human gastric epithelial cells

    Yi-Ying Wu; Hwei-Fang Tsai; We-Cheng Lin; Ai-Hsiang Chou; Hui-Ting Chen; Jyh-Chin Yang; Ping-I Hsu; Ping-Ning Hsu

    2004-01-01

    AIM: To investigate the relations between tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) and Helicobacter pylori(H pylori) infection in apoptosis of gastric epithelial cells and to assess the expression of TRAIL onthe surface of infiltrating T-cells in Hpylori-infected gastric mucosa.METHODS: Human gastric epithelial cell lines and primary gastric epithelial cells were co-cultured with H pylori in vitro, then recombinant TRAIL proteins were added to the culture. Apoptosis of gastric epithelial cells was determined by a specific ELISA for cell death. Infiltrating lymphocytes were isolated from H pylori-infected gastric mucosa, and expression of TRAIL in T cells was analyzed by flow cytometry.RESULTS: The apoptosis of gastric epithelial cell lines and primary human gastric epithelial cells was mildly increased by interaction with either TRAIL or H pylorialone. Interestingly,the apoptotic indices were markedly elevated when gastric epithelial cells were incubated with both TRAIL and H pylori (Control vsTRAIL and H pylori: 0.51±0.06 vs 2.29±0.27,P = 0.018). A soluble TRAIL receptor (DR4-Fc) could specifically block the TRAIL-mediated apoptosis. Further studies demonstrated that infiltrating T-cells in gastric mucosa expressed TRAIL on their surfaces, and the induction of TRAIL sensitivity by H pylori was dependent upon direct cell contact of viable bacteria, but not CagA and VacA of H pylori.CONCLUSION: H pylori can sensitize human gastric epithelial ceils and enhance susceptibility to TRAIL-mediated apoptosis. Modulation of host cell sensitivity to apoptosis by bacterial interaction adds a new dimension to the immunopathogenesis of H pylori infection.

  7. Agarol, an ergosterol derivative from Agaricus blazei, induces caspase-independent apoptosis in human cancer cells.

    Shimizu, Takamitsu; Kawai, Junya; Ouchi, Kenji; Kikuchi, Haruhisa; Osima, Yoshiteru; Hidemi, Rikiishi

    2016-04-01

    Agaricus blazei (A. blazei) is a mushroom with many biological effects and active ingredients. We purified a tumoricidal substance from A. blazei, an ergosterol derivative, and named it 'Agarol'. Cytotoxic effects of Agarol were determined by the MTT assay using A549, MKN45, HSC-3, and HSC-4 human carcinoma cell lines treated with Agarol. Apoptosis was detected by flow cytometry analysis. Reactive oxygen species (ROS) levels and mitochondria membrane potential (∆ψm) were also determined by flow cytometry. Western blot analysis was used to quantify the expression of apoptosis-related proteins. Agarol predominantly induced apoptosis in two p53-wild cell lines (A549 and MKN45) compared to the other p53-mutant cell lines (HSC-3 and HSC-4). Further mechanistic studies revealed that induction of apoptosis is associated with increased generation of ROS, reduced ∆ψm, release of apoptosis-inducing factor (AIF) from the mitochondria to the cytosol, upregulation of Bax, and downregulation of Bcl-2. Caspase-3 activities did not increase, and z-VAD-fmk, a caspase inhibitor, did not inhibit the Agarol-induced apoptosis. These findings indicate that Agarol induces caspase-independent apoptosis in human carcinoma cells through a mitochondrial pathway. The in vivo anticancer activity of Agarol was confirmed in a xenograft murine model. This study suggests a molecular mechanism by which Agarol induces apoptosis in human carcinoma cells and indicates the potential use of Agarol as an anticancer agent. PMID:26893131

  8. Nicotinamide-Induced Apoptosis Can Be Enhanced by Melatonin in Mouse Myeloma Cells

    ZHANG Guiyou; SHENG Hongzhi; LIU Jia

    2006-01-01

    The mechanism of apoptosis induced by nicotinamide was investigated by treating mouse myeloma cells (Sp2/0) with various concentrations of nicotinamide. The typical hallmarks of apoptosis, including chromatin condensation and DNA fragmentation, were detected when cells were treated with nicotinamide at concentrations of 30, 40, 50, and 60 mmol/L. The apoptosis percentage increased with increasing nicotinamide concentration. Interestingly, the strong antioxidant melatonin did not restrain the apoptosis induced by nicotinamide in mouse myeloma cells but greatly increased the induction of nicotinamide on apoptosis. When cells were preincubated with 0.1, 1, and 10 mmol/L melatonin before nicotinamide induction, the percentage of apoptosis induced by 50 mmol/L nicotinamide markedly increased with increasing melatonin concentration. These results suggest that apoptosis induced by nicotinamide has no relationship with oxidative stress and melatonin could enhance nicotinamide-induced apoptosis in mouse myeloma cells by stimulating cell division in a certain manner. Nicotinamide may provide a new method to treat some kinds of tumors with no damage to normal tissues.

  9. Valproic acid triggers differentiation and apoptosis in AML1/ETO-positive leukemic cells specifically.

    Zapotocky, Michal; Mejstrikova, Ester; Smetana, Karel; Stary, Jan; Trka, Jan; Starkova, Julia

    2012-06-28

    Valproic acid (VPA) has extensive effects on leukemic blasts through its inhibition of histone deacetylases. The main goal of this study was to identify the subgroup of patients who may benefit most from VPA treatment. We examined the significance of t(8;21) chromosomal aberration for VPA treatment response among acute myeloid leukemia (AML) patients by direct comparison of AML1/ETO-negative vs. positive leukemic cell-lines as well as bone marrow blasts from AML patients. In t(8;21) AML, leukemogenesis is supposed to be induced via aberrant recruitment of histone deacetylases. AML cell lines of different genotypes (Kasumi-1, Kasumi-6, MV4;11, K562) and diagnostic bone marrow samples from patients were treated with VPA. VPA induced apoptosis in AML1/ETO-positive and MLL-AF4-positive cells in a dose-dependent manner. Differentiation, as indicated by changes in immunophenotype, was observed only in AML1/ETO-positive cells. VPA increased the expression of AML1 target genes - PU.1, C/EBPa, BPI and IGFBP7 only in AML1/ETO-positive cells. This AML1/ETO-specific effect was confirmed also using patient blasts isolated at the time of diagnosis. AML1/ETO-positive leukemia shows specific mechanism of VPA residing from differentiation followed by apoptosis that is accompanied by an increase in the expression of repressed AML1 target genes. Our data suggest that AML1/ETO-positive patients might derive the greatest benefit from VPA treatment. PMID:22261333

  10. Curcumin enhances TRAIL-induced apoptosis of breast cancer cells by regulating apoptosis-related proteins

    Park, S.; Cho, D. J.; Anděra, Ladislav; Suh, N.; Kim, I.

    2013-01-01

    Roč. 383, 1-2 (2013), s. 39-48. ISSN 0300-8177 Institutional support: RVO:68378050 Keywords : TRAIL * curcumin * apoptosis * breast cancer Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.388, year: 2013

  11. Kefir induces apoptosis and inhibits cell proliferation in human acute erythroleukemia.

    Jalali, Fatemeh; Sharifi, Mohammadreza; Salehi, Rasoul

    2016-01-01

    Acute erythroleukemia is an uncommon subtype of acute myeloid leukemia which has been considered to be a subtype of AML with a worse prognosis. Intensive chemotherapy is the first line of treatment. In recent years, the effect of kefir on some malignancies has been experimented. Kefir is a kind of beverage, which obtained by incubation of kefir grains with raw milk. Kefir grains are a symbiotic complex of different kinds of yeasts and bacteria, especially lactic acid bacteria which gather in a mostly carbohydrate matrix, named kefiran. We investigated the effect of kefir on acute erythroleukemia cell line (KG-1) and peripheral blood mononuclear cells (PBMCs). The cell line and PBMCs were treated with different doses of kefir and milk and incubated for three different times. We used Polymixin B to block the lipopolysaccharide and NaOH (1 mol/l) to neutralize the acidic media. Viability was detected by MTT assay. Apoptosis and necrosis were assessed by annexin-propidium iodide staining. Our results showed that kefir induced apoptosis and necrosis in KG-1 cell line. It was revealed that kefir decreased proliferation in erythroleukemia cell line. We did not observe a remarkable effect of kefir on PBMCs. Our study suggested that kefir may have potential to be an effective treatment for erythroleukemia. PMID:26708130

  12. Comparison of bleomycin-induced pulmonary apoptosis between NMRI mice and C57BL/6 mice

    Safaeian, L.; Jafarian-Dehkordi, A.; Rabbani, M.; Sadeghi, H.M.; Afshar-Moghaddam, N.; Sarahroodi, S.

    2013-01-01

    Apoptosis has a critical role in the pathogenesis of bleomycin induced-pulmonary fibrosis. The severity of fibrosis varies among different strains of mice. Recent studies have indicated that expression of apoptotic regulatory genes may be specific in different cell types in various strains. In this study, bleomycin-induced pulmonary apoptosis in NMRI (Naval Medical Research Institute, USA) albino mice were compared with C57BL/6 black mice. Pulmonary fibrosis induced by single intratracheal ad...

  13. Androgen via p21 Inhibits Tumor Necrosis Factor α-induced JNK Activation and Apoptosis*

    Tang, Fangming; Kokontis, John; Lin, Yuting; Liao, Shutsung; Lin, Anning; Xiang, Jialing

    2009-01-01

    The male hormone androgen is a growth/survival factor for its target tissues or organs. Yet, the underlying mechanism is incompletely understood. Here, we report that androgen via p21 inhibits tumor necrosis factor α-induced JNK activation and apoptosis. Inhibition by androgen requires the transcription activity of androgen receptor (AR) and de novo protein synthesis. Androgen·AR induces expression of p21 that in turn inhibits tumor necrosis factor α-induced JNK and apoptosis. Furthermore, ge...

  14. Inonotus obliquus Protects against Oxidative Stress-Induced Apoptosis and Premature Senescence

    Yun, Jong Seok; Pahk, Jung Woon; Lee, Jong Seok; Shin, Won Cheol; Lee, Shin Young; Hong, Eock Kee

    2011-01-01

    In this study, we investigated the cytoprotective effects of Inonotus obliquus against oxidative stress-induced apoptosis and premature senescence. Pretreatment with I. obliquus scavenged intracellular ROS and prevented lipid peroxidation in hydrogen peroxide-treated human fibroblasts. As a result, I. obliquus exerted protective effects against hydrogen peroxide-induced apoptosis and premature senescence in human fibroblasts. In addition, I. obliquus suppressed UV-induced morphologic skin cha...

  15. Autotaxin is induced by TSA through HDAC3 and HDAC7 inhibition and antagonizes the TSA-induced cell apoptosis

    Zhang Junjie

    2011-02-01

    Full Text Available Abstract Background Autotaxin (ATX is a secreted glycoprotein with the lysophospholipase D (lysoPLD activity to convert lysophosphatidylcholine (LPC into lysophosphatidic acid (LPA, a bioactive lysophospholipid involved in diverse biological actions. ATX is highly expressed in some cancer cells and contributes to their tumorigenesis, invasion, and metastases, while in other cancer cells ATX is silenced or expressed at low level. The mechanism of ATX expression regulation in cancer cells remains largely unknown. Results In the present study, we demonstrated that trichostatin A (TSA, a well-known HDAC inhibitor (HDACi, significantly induced ATX expression in SW480 and several other cancer cells with low or undetectable endogenous ATX expression. ATX induction could be observed when HDAC3 and HDAC7 were down-regulated by their siRNAs. It was found that HDAC7 expression levels were low in the cancer cells with high endogenous ATX expression. Exogenous over-expression of HDAC7 inhibited ATX expression in these cells in a HDAC3-dependent manner. These data indicate that HDAC3 and HDAC7 collaboratively suppress ATX expression in cancer cells, and suggest that TSA induce ATX expression by inhibiting HDAC3 and HDAC7. The biological significance of this regulation mechanism was revealed by demonstrating that TSA-induced ATX protected cancer cells against TSA-induced apoptosis by producing LPA through its lysoPLD activity, which could be reversed by BrP-LPA and S32826, the inhibitors of the ATX-LPA axis. Conclusions We have demonstrated that ATX expression is repressed by HDAC3 and HDAC7 in cancer cells. During TSA treatment, ATX is induced due to the HDAC3 and HDAC7 inhibition and functionally antagonizes the TSA-induced apoptosis. These results reveal an internal HDACi-resistant mechanism in cancer cells, and suggest that the inhibition of ATX-LPA axis would be helpful to improve the efficacy of HDACi-based therapeutics against cancer.

  16. Involvement of ASK1 activation in apoptosis induced by NPe6-PDT

    Liu, Lei; Zhang, Zhen-zhen; Zhang, Zhigang

    2010-02-01

    Photodynamic therapy (PDT) employing photosensiter N-aspartyl chlorin e6 (NPe6) can induce lysosome disruption and initiate apoptotic pathway. Apoptosis signal-regulating kinase (ASK1) is an important regulator of apoptosis in response to various stresses, such as reactive oxygen species (ROS), endoplasmic reticulum (ER) stress, lipopolysaccharide (LPS) and calcium influx. In this study, we investigated the molecular mechanisms of apoptosis induced by NPe6-PDT in ASTC-a-1 cells. The results showed that the activities of ASK1 increased in response to NPe6-PDT. Over-expression of wild-type or activated mutant of ASK1 could obviously decrease cell viability and increase cell death; while inhibition of ASK1 significantly decreased cell apoptosis. These results suggested that ASK1 plays an important role in apoptosis induced by NPe6-PDT.

  17. A Triterpenoid from Thalictrum fortunei Induces Apoptosis in BEL-7402 Cells Through the P53-Induced Apoptosis Pathway

    Lvyi Chen

    2011-11-01

    Full Text Available Thalictrum fortunei S. Moore, a perennial plant distributed in the southeastern part of China, has been used in Traditional Chinese Medicine for thousands of years for its antitumor, antibacterial and immunoregulatory effects. In order to investigate the active components and the mechanism of the anti-tumor effects of Thalictrum fortunei, the growth inhibitory effects of eight triterpenoids isolated from the aerial parts of the plant on tumor cell lines were examined by 3-(4,5-dimethylthiazoy1-3,5-diphenyltetrazolium bromide (MTT assay. The MTT-assay results showed that the inhibitory activity of 3-O-β-D-glucopyranosyl-(1→4-β-D-fucopyranosyl(22S,24Z-cycloart-24-en-3β,22,26-triol 26-O-β-D-glucopyranoside (1 was stronger than that of the other seven tested triterpenoids on human hepatoma Bel-7402 cell line (Bel-7402, human colon lovo cells (LoVo, human non-small cells lung cancer NCIH-460 cells (NCIH-460 and human gastric carcinoma SGC-7901 cells (SGC-7901 after 48 h treatment in vitro, with the IC50 values of 66.4, 84.8, 73.5, 89.6 μM, respectively. Moreover, the antitumor mechanism of compound 1 on Bel-7402 cell was explored through nucleus dyeing, fluorescence assay, flow cytometry and western blot. The flow cytometric analysis results revealed that compound 1 caused apoptosis and mitochondrial membrane potential (MMP loss in Bel-7402 cells. A fluorescence assay indicated that intracellular reactive oxygen species (ROS were markedly provoked by compound 1 treatment compared to control cells. Immunoblot results showed that compound 1 significantly increased the expression levels of cleaved caspase-3, P53 and Bax protein, and decreased the expression level of Bcl-2 protein. These findings indicate that compound 1 inhibits the growth activity of tumor cells, probably through the P53 protein-induced apoptosis pathway.

  18. Targeting proliferating cell nuclear antigen and its protein interactions induces apoptosis in multiple myeloma cells.

    Rebekka Müller

    Full Text Available Multiple myeloma is a hematological cancer that is considered incurable despite advances in treatment strategy during the last decade. Therapies targeting single pathways are unlikely to succeed due to the heterogeneous nature of the malignancy. Proliferating cell nuclear antigen (PCNA is a multifunctional protein essential for DNA replication and repair that is often overexpressed in cancer cells. Many proteins involved in the cellular stress response interact with PCNA through the five amino acid sequence AlkB homologue 2 PCNA-interacting motif (APIM. Thus inhibiting PCNA's protein interactions may be a good strategy to target multiple pathways simultaneously. We initially found that overexpression of peptides containing the APIM sequence increases the sensitivity of cancer cells to contemporary therapeutics. Here we have designed a cell-penetrating APIM-containing peptide, ATX-101, that targets PCNA and show that it has anti-myeloma activity. We found that ATX-101 induced apoptosis in multiple myeloma cell lines and primary cancer cells, while bone marrow stromal cells and primary healthy lymphocytes were much less sensitive. ATX-101-induced apoptosis was caspase-dependent and cell cycle phase-independent. ATX-101 also increased multiple myeloma cells' sensitivity against melphalan, a DNA damaging agent commonly used for treatment of multiple myeloma. In a xenograft mouse model, ATX-101 was well tolerated and increased the anti-tumor activity of melphalan. Therefore, targeting PCNA by ATX-101 may be a novel strategy in multiple myeloma treatment.

  19. Characterization and Inducing Melanoma Cell Apoptosis Activity of Mannosylerythritol Lipids-A Produced from Pseudozyma aphidis.

    Fan, Linlin; Li, Hongji; Niu, Yongwu; Chen, Qihe

    2016-01-01

    Mannosylerythritol lipids (MELs) are natural glycolipid biosurfactants which have potential applications in the fields of food, cosmetic and medicine. In this study, MELs were produced from vegetable oil by Pseudozyma aphidis. Their structural data through LC/MS, GC/MS and NMR analysis revealed that MEL-A with two acetyls was the major compound and the identified homologs of MEL-A contained a length of C8 to C14 fatty acid chains. This glycolipid exhibited a surface tension of 27.69 mN/m at a critical micelle concentration (CMC), self-assembling into particles in the water solution. It was observed to induce cell growth-inhibition and apoptosis of B16 melanoma cells in a dose-dependent manner, as well as cause cell cycle arrest at the S phase. Further quantitative RT-PCR analysis and western blotting revealed an increasing tendency of both mRNA and protein expressions of Caspase-12, CHOP, GRP78 and Caspase-3, and a down-regulation of protein Bcl-2. Combined with the up regulation of signaling IRE1 and ATF6, it can be speculated that MEL-A-induced B16 melanoma cell apoptosis was associated with the endoplasmic reticulum stress (ERS). PMID:26828792

  20. Cadmium induces apoptosis in anterior pituitary cells that can be reversed by treatment with antioxidants

    Cadmium (Cd2+) is an ubiquitous toxic metal that is involved in a variety of pathological conditions. Several reports indicate that Cd2+ alters normal pituitary hormone secretion; however, little is known about the mechanisms that induce this misregulation. This paper reports the effect of Cd2+ on anterior pituitary cell viability and its relation to prolactin secretion. Cd2+ concentrations above 10 μM were found to be cytotoxic for pituitary cells. Morphological studies as well as DNA ladder fragmentation and caspase activation showed that Cd2+-treated cells undergo apoptosis. Even though several hours were needed to detect Cd2+-induced cytotoxicity, the effect of the metal became irreversible very quickly, requiring only 3 h of treatment. Prolactin release (measured at 48 h) was inhibited when the cells were exposed to Cd2+ for 1 h, before any change in cell viability was observed. The antioxidants N-acetyl-cysteine and Trolox (a hydrosoluble derivative of vitamin E), but not ascorbic acid, reversed both Cd2+-mediated cytotoxicity and the inhibition of prolactin release, supporting the involvement of oxidative stress in the mechanism of Cd2+ action. In summary, the present work demonstrates that Cd2+ is cytotoxic for anterior pituitary cells, that this effect is due to an induction of apoptosis, and that it can be reversed by antioxidants

  1. Albumin resuscitation protects against traumatic/hemorrhagic shock-induced lung apoptosis in rats

    Yun ZHANG; Zhong-yan LIANG; Shao-yang ZHANG; Fang-fang HUANG; Wei WU; Yuan GAO; Zuo-bing CHEN

    2008-01-01

    Objective: To determine the effects of albumin administration on lung injury and apoptosis in traumatic/hemorrhagic shock (T/HS) rats. Methods: Studies were performed on an in vivo model of spontaneously breathing rats with induced T/HS; the rats were subjected to femur fracture, ischemia for 30 min, and reperfusion for 20 rain with Ringer's lactate solution (RS) or 5% (w/v) albumin (ALB), and the left lower lobes of the lungs were resected. Results: Albumin administered during reperfusion markedly attenuated injury of the lung and decreased the concentration of lactic acid and the number of in situ TdT-mediated dUTP nick-end labelling (TUNEL)-positive cells. Moreover, immunohistochemistry performed 24 h after reperfusion revealed increases in the level of nuclear factor κB (NF-κB), and phosphorylated p38 mitogen-activated protein kinase (MAPK) in the albumin-untreated group was down-regulated by albumin treatment when compared with the sham rats. Conclusion: Resuscitation with albumin attenuates tissue injury and inhibits T/HS-induced apoptosis in the lung via the p38 MAPK signal transduction pathway that functions to stimulate the activation of NF-κB.

  2. JWA is required for arsenic trioxide induced apoptosis in HeLa and MCF-7 cells via reactive oxygen species and mitochondria linked signal pathway

    Arsenic trioxide, emerging as a standard therapy for refractory acute promyelocytic leukemia, induces apoptosis in a variety of malignant cell lines. JWA, a novel retinoic acid-inducible gene, is known to be involved in apoptosis induced by various agents, for example, 12-O-tetradecanoylphorbol 13-acetate, N-4-hydroxy-phenyl-retinamide and arsenic trioxide. However, the molecular mechanisms underlying how JWA gene is functionally involved in apoptosis remain largely unknown. Herein, our studies demonstrated that treatment of arsenic trioxide produced apoptosis in HeLa and MCF-7 cells in a dose-dependent manner and paralleled with increased JWA expression. JWA expression was dependent upon generation of intracellular reactive oxygen species induced by arsenic trioxide. Knockdown of JWA attenuated arsenic trioxide induced apoptosis, and was accompanied by significantly reduced activity of caspase-9, enhanced Bad phosphorylation and inhibited MEK1/2, ERK1/2 and JNK phosphorylations. Arsenic trioxide induced loss of mitochondrial transmembrane potential was JWA-dependent. These findings suggest that JWA may serve as a pro-apoptotic molecule to mediate arsenic trioxide triggered apoptosis via a reactive oxygen species and mitochondria-associated signal pathway

  3. Production of multiple brain-like ganglioside species is dispensable for fas-induced apoptosis of lymphoid cells.

    Iuliana Popa

    Full Text Available Activation of an acid sphingomyelinase (aSMase leading to a biosynthesis of GD3 disialoganglioside has been associated with Fas-induced apoptosis of lymphoid cells. The present study was undertaken to clarify the role of this enzyme in the generation of gangliosides during apoptosis triggered by Fas ligation. The issue was addressed by using aSMase-deficient and aSMase-corrected cell lines derived from Niemann-Pick disease (NPD patients. Fas cross-linking elicited a rapid production of large amounts of complex a- and b-series species of gangliosides with a pattern and a chromatographic behavior as single bands reminiscent of brain gangliosides. The gangliosides were synthesized within the first ten minutes and completely disappeared within thirty minutes after stimulation. Noteworthy is the observation that GD3 was not the only ganglioside produced. The production of gangliosides and the onset of apoptotic hallmarks occurred similarly in both aSMase-deficient and aSMase-corrected NPD lymphoid cells, indicating that aSMase activation is not accountable for ganglioside generation. Hampering ganglioside production by inhibiting the key enzyme glucosylceramide synthase did not abrogate the apoptotic process. In addition, GM3 synthase-deficient lymphoid cells underwent Fas-induced apoptosis, suggesting that gangliosides are unlikely to play an indispensable role in transducing Fas-induced apoptosis of lymphoid cells.

  4. Production of multiple brain-like ganglioside species is dispensable for fas-induced apoptosis of lymphoid cells.

    Popa, Iuliana; Therville, Nicole; Carpentier, Stéphane; Levade, Thierry; Cuvillier, Olivier; Portoukalian, Jacques

    2011-01-01

    Activation of an acid sphingomyelinase (aSMase) leading to a biosynthesis of GD3 disialoganglioside has been associated with Fas-induced apoptosis of lymphoid cells. The present study was undertaken to clarify the role of this enzyme in the generation of gangliosides during apoptosis triggered by Fas ligation. The issue was addressed by using aSMase-deficient and aSMase-corrected cell lines derived from Niemann-Pick disease (NPD) patients. Fas cross-linking elicited a rapid production of large amounts of complex a- and b-series species of gangliosides with a pattern and a chromatographic behavior as single bands reminiscent of brain gangliosides. The gangliosides were synthesized within the first ten minutes and completely disappeared within thirty minutes after stimulation. Noteworthy is the observation that GD3 was not the only ganglioside produced. The production of gangliosides and the onset of apoptotic hallmarks occurred similarly in both aSMase-deficient and aSMase-corrected NPD lymphoid cells, indicating that aSMase activation is not accountable for ganglioside generation. Hampering ganglioside production by inhibiting the key enzyme glucosylceramide synthase did not abrogate the apoptotic process. In addition, GM3 synthase-deficient lymphoid cells underwent Fas-induced apoptosis, suggesting that gangliosides are unlikely to play an indispensable role in transducing Fas-induced apoptosis of lymphoid cells. PMID:21629700

  5. Transient axonal glycoprotein-1 induces apoptosis-related gene expression without triggering apoptosis in U251 glioma cells

    Haigang Chang; Xiaodan Jiang; Shanshan Song; Zhongcan Chen; Yaxiao Wang; Lujun Yang; Mouxuan Du; Yiquan Ke; Ruxiang Xu; Baozhe Jin

    2014-01-01

    Previous studies show that transient axonal glycoprotein-1, a ligand of amyloid precursor pro-tein, increases the secretion of amyloid precursor protein intracellular domain and is involved in apoptosis in Alzheimer’s disease. In this study, we examined the effects of transient axonal glyco-protein-1 on U251 glioma cells. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay showed that transient axonal glycoprotein-1 did not inhibit the proliferation of U251 cells, but promoted cell viability. The terminal deoxynucleotidyl transferase dUTP nick end labeling assay showed that transient axonal glycoprotein-1 did not induce U251 cell apoptosis. Real-time PCR revealed that transient axonal glycoprotein-1 substantially upregulated levels of amyloid precursor protein intracellular C-terminal domain, and p53 and epidermal growth factor recep-tor mRNA expression. Thus, transient axonal glycoprotein-1 increased apoptosis-related gene expression in U251 cells without inducing apoptosis. Instead, transient axonal glycoprotein-1 promoted the proliferation of these glioma cells.

  6. Apoptosis-like death in bacteria induced by HAMLET, a human milk lipid-protein complex.

    Anders P Hakansson

    Full Text Available BACKGROUND: Apoptosis is the primary means for eliminating unwanted cells in multicellular organisms in order to preserve tissue homeostasis and function. It is characterized by distinct changes in the morphology of the dying cell that are orchestrated by a series of discrete biochemical events. Although there is evidence of primitive forms of programmed cell death also in prokaryotes, no information is available to suggest that prokaryotic death displays mechanistic similarities to the highly regulated programmed death of eukaryotic cells. In this study we compared the characteristics of tumor and bacterial cell death induced by HAMLET, a human milk complex of alpha-lactalbumin and oleic acid. METHODOLOGY/PRINCIPAL FINDINGS: We show that HAMLET-treated bacteria undergo cell death with mechanistic and morphologic similarities to apoptotic death of tumor cells. In Jurkat cells and Streptococcus pneumoniae death was accompanied by apoptosis-like morphology such as cell shrinkage, DNA condensation, and DNA degradation into high molecular weight fragments of similar sizes, detected by field inverse gel electrophoresis. HAMLET was internalized into tumor cells and associated with mitochondria, causing a rapid depolarization of the mitochondrial membrane and bound to and induced depolarization of the pneumococcal membrane with similar kinetic and magnitude as in mitochondria. Membrane depolarization in both systems required calcium transport, and both tumor cells and bacteria were found to require serine protease activity (but not caspase activity to execute cell death. CONCLUSIONS/SIGNIFICANCE: Our results suggest that many of the morphological changes and biochemical responses associated with apoptosis are present in prokaryotes. Identifying the mechanisms of bacterial cell death has the potential to reveal novel targets for future antimicrobial therapy and to further our understanding of core activation mechanisms of cell death in eukaryote cells.

  7. Dose-effect relationship of apoptosis induced by fission-neutron in murine thymocytes

    Objective: To investigate the effectiveness of high LET fission-neutron to induce apoptosis in murine thymocytes and to compare it with that of low LET 60Co γ-ray. Methods: Apoptosis induction was studied qualitatively by light and transmission electron microscopy and DNA gel electrophoresis,also quantitatively by flow cytometry(FCM) and diphenylamine (DPA)methods. Results: DNA ladders of murine thymocytes were detectable, the typical apoptosis of thymocytes could be observed morphologically by means of light and electron microscopy at 6 h after fission-neutron irradiation with doses ranging from 0.5 to 5.0 Gy, meanwhile the percentages of apoptosis increased with increasing doses. After exposure to γ-rays with doses ranging from 1.0 to 30 Gy, the experimental results were similar to those from neutron radiation. The incidence of apoptosis peaked at about 20 Gy, the percentages did not increase further when doses increased. Conclusion: Apoptosis of murine thymocytes can be induced when mice are exposed to either fission-neutron (0.5-5.0 Gy) or to γ-ray (1-30 Gy). Although the relationship between apoptosis and radiation doses is similar, the percentage of apoptosis induced by neutron irradiation is higher than that induced by γ-irradiation. The RBE values of fission-neutron for inducing apoptosis murine thymocytes are 2.09 (by FCM method) and 2.37 (by DPA method), respectively. These results also suggest that fission-neutron-induced murine immune tissue is more severe than that induced by γ-rays at several hours post-irradiation and this might be the basis for heavy damage to immune tissues induced by fission-neutron-irradiation in later period

  8. 14,15-EET promotes mitochondrial biogenesis and protects cortical neurons against oxygen/glucose deprivation-induced apoptosis

    Highlights: • 14,15-EET inhibits OGD-induced apoptosis in cortical neurons. • Mitochondrial biogenesis of cortical neurons is promoted by 14,15-EET. • 14,15-EET preserves mitochondrial function of cortical neurons under OGD. • CREB mediates effect of 14,15-EET on mitochondrial biogenesis and function. - Abstract: 14,15-Epoxyeicosatrienoic acid (14,15-EET), a metabolite of arachidonic acid, is enriched in the brain cortex and exerts protective effect against neuronal apoptosis induced by ischemia/reperfusion. Although apoptosis has been well recognized to be closely associated with mitochondrial biogenesis and function, it is still unclear whether the neuroprotective effect of 14,15-EET is mediated by promotion of mitochondrial biogenesis and function in cortical neurons under the condition of oxygen–glucose deprivation (OGD). In this study, we found that 14,15-EET improved cell viability and inhibited apoptosis of cortical neurons. 14,15-EET significantly increased the mitochondrial mass and the ratio of mitochondrial DNA to nuclear DNA. Key makers of mitochondrial biogenesis, peroxisome proliferator activator receptor gamma-coactivator 1 alpha (PGC-1α), nuclear respiratory factor 1 (NRF-1) and mitochondrial transcription factor A (TFAM), were elevated at both mRNA and protein levels in the cortical neurons treated with 14,15-EET. Moreover, 14,15-EET markedly attenuated the decline of mitochondrial membrane potential, reduced ROS, while increased ATP synthesis. Knockdown of cAMP-response element binding protein (CREB) by siRNA blunted the up-regulation of PGC-1α and NRF-1 stimulated by 14,15-EET, and consequently abolished the neuroprotective effect of 14,15-EET. Our results indicate that 14,15-EET protects neurons from OGD-induced apoptosis by promoting mitochondrial biogenesis and function through CREB mediated activation of PGC-1α and NRF-1

  9. 14,15-EET promotes mitochondrial biogenesis and protects cortical neurons against oxygen/glucose deprivation-induced apoptosis

    Wang, Lai; Chen, Man; Yuan, Lin; Xiang, Yuting [Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing (China); Zheng, Ruimao, E-mail: rmzheng@pku.edu.cn [Department of Anatomy, Histology and Embryology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing (China); Zhu, Shigong, E-mail: sgzhu@bjmu.edu.cn [Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing (China)

    2014-07-18

    Highlights: • 14,15-EET inhibits OGD-induced apoptosis in cortical neurons. • Mitochondrial biogenesis of cortical neurons is promoted by 14,15-EET. • 14,15-EET preserves mitochondrial function of cortical neurons under OGD. • CREB mediates effect of 14,15-EET on mitochondrial biogenesis and function. - Abstract: 14,15-Epoxyeicosatrienoic acid (14,15-EET), a metabolite of arachidonic acid, is enriched in the brain cortex and exerts protective effect against neuronal apoptosis induced by ischemia/reperfusion. Although apoptosis has been well recognized to be closely associated with mitochondrial biogenesis and function, it is still unclear whether the neuroprotective effect of 14,15-EET is mediated by promotion of mitochondrial biogenesis and function in cortical neurons under the condition of oxygen–glucose deprivation (OGD). In this study, we found that 14,15-EET improved cell viability and inhibited apoptosis of cortical neurons. 14,15-EET significantly increased the mitochondrial mass and the ratio of mitochondrial DNA to nuclear DNA. Key makers of mitochondrial biogenesis, peroxisome proliferator activator receptor gamma-coactivator 1 alpha (PGC-1α), nuclear respiratory factor 1 (NRF-1) and mitochondrial transcription factor A (TFAM), were elevated at both mRNA and protein levels in the cortical neurons treated with 14,15-EET. Moreover, 14,15-EET markedly attenuated the decline of mitochondrial membrane potential, reduced ROS, while increased ATP synthesis. Knockdown of cAMP-response element binding protein (CREB) by siRNA blunted the up-regulation of PGC-1α and NRF-1 stimulated by 14,15-EET, and consequently abolished the neuroprotective effect of 14,15-EET. Our results indicate that 14,15-EET protects neurons from OGD-induced apoptosis by promoting mitochondrial biogenesis and function through CREB mediated activation of PGC-1α and NRF-1.

  10. Nitric oxide-induced eosinophil apoptosis is dependent on mitochondrial permeability transition (mPT, JNK and oxidative stress: apoptosis is preceded but not mediated by early mPT-dependent JNK activation

    Ilmarinen-Salo Pinja

    2012-08-01

    Full Text Available Abstract Background Eosinophils are critically involved in the pathogenesis of asthma. Nitric oxide (NO is produced in high amounts in asthmatic lungs and has an important role as a regulator of lung inflammation. NO was previously shown to induce eosinophil apoptosis mediated via c-jun N-terminal kinase (JNK and caspases. Our aim was to clarify the cascade of events leading to NO-induced apoptosis in granulocyte macrophage-colony stimulating factor (GM-CSF-treated human eosinophils concentrating on the role of mitochondria, reactive oxygen species (ROS and JNK. Methods Apoptosis was determined by flow cytometric analysis of relative DNA content, by Annexin-V labelling and/or morphological analysis. Immunoblotting was used to study phospho-JNK (pJNK expression. Mitochondrial membrane potential was assessed by JC-1-staining and mitochondrial permeability transition (mPT by loading cells with calcein acetoxymethyl ester (AM and CoCl2 after which flow cytometric analysis was conducted. Statistical significance was calculated by repeated measures analysis of variance (ANOVA or paired t-test. Results NO-donor S-nitroso-N-acetyl-D,L-penicillamine (SNAP induced late apoptosis in GM-CSF-treated eosinophils. SNAP-induced apoptosis was suppressed by inhibitor of mPT bongkrekic acid (BA, inhibitor of JNK SP600125 and superoxide dismutase-mimetic AEOL 10150. Treatment with SNAP led to late loss of mitochondrial membrane potential. Additionally, we found that SNAP induces early partial mPT (1 h that was followed by a strong increase in pJNK levels (2 h. Both events were prevented by BA. However, these events were not related to apoptosis because SNAP-induced apoptosis was prevented as efficiently when BA was added 16 h after SNAP. In addition to the early and strong rise, pJNK levels were less prominently increased at 20–30 h. Conclusions Here we demonstrated that NO-induced eosinophil apoptosis is mediated via ROS, JNK and late mPT. Additionally

  11. Melatonin and Doxorubicin synergistically induce cell apoptosis in human hepatoma cell lines

    2010-01-01

    AIM:To investigate whether Melatonin has synergistic effects with Doxorubicin in the growth-inhibition and apoptosis-induction of human hepatoma cell lines HepG2 and Bel-7402.METHODS:The synergism of Melatonin and Doxorubicin inhibited the cell growth and induced cell apoptosis in human hepatoma cell lines HepG2 and Bel-7402.Cell viability was analyzed by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide(MTT)assay.Cell apoptosis was evaluated using TUNEL method and flow cytometry.Apoptosis-r...

  12. Targeting ceramide metabolic pathway induces apoptosis in human breast cancer cell lines

    The sphingolipid ceramide is a pro apoptotic molecule of ceramide metabolic pathway and is hydrolyzed to proliferative metabolite, sphingosine 1 phosphate by the action of acid ceramidase. Being upregulated in the tumors of breast, acid ceramidase acts as a potential target for breast cancer therapy. We aimed at targeting this enzyme with a small molecule acid ceramidase inhibitor, Ceranib 2 in human breast cancer cell lines MCF 7 and MDA MB 231. Ceranib 2 effectively inhibited the growth of both the cell lines in dose and time dependant manner. Morphological apoptotic hallmarks such as chromatin condensation, fragmented chromatin were observed in AO/EtBr staining. Moreover, ladder pattern of fragmented DNA observed in DNA gel electrophoresis proved the apoptotic activity of Ceranib 2 in breast cancer cell lines. The apoptotic events were associated with significant increase in the expression of pro-apoptotic genes (Bad, Bax and Bid) and down regulation of anti-apoptotic gene (Bcl 2). Interestingly, increase in sub G1 population of cell cycle phase analysis and elevated Annexin V positive cells after Ceranib 2 treatment substantiated its apoptotic activity in MCF 7 and MDA MB 231 cell lines. Thus, we report Ceranib 2 as a potent therapeutic agent against both ER+ and ER− breast cancer cell lines. - Highlights: • Acid Ceramidase inhibitor, Ceranib 2 induced apoptosis in Breast cancer cell lines (MCF 7 and MDA MB 231 cell lines). • Apoptosis is mediated by DNA fragmentation and cell cycle arrest. • Ceranib 2 upregulated the expression of pro-apoptotic genes and down regulated anti-apoptotic gene expression. • More potent compared to the standard drug Tamoxifen

  13. Targeting ceramide metabolic pathway induces apoptosis in human breast cancer cell lines

    Vethakanraj, Helen Shiphrah; Babu, Thabraz Ahmed; Sudarsanan, Ganesh Babu; Duraisamy, Prabhu Kumar; Ashok Kumar, Sekar, E-mail: sekarashok@gmail.com

    2015-08-28

    The sphingolipid ceramide is a pro apoptotic molecule of ceramide metabolic pathway and is hydrolyzed to proliferative metabolite, sphingosine 1 phosphate by the action of acid ceramidase. Being upregulated in the tumors of breast, acid ceramidase acts as a potential target for breast cancer therapy. We aimed at targeting this enzyme with a small molecule acid ceramidase inhibitor, Ceranib 2 in human breast cancer cell lines MCF 7 and MDA MB 231. Ceranib 2 effectively inhibited the growth of both the cell lines in dose and time dependant manner. Morphological apoptotic hallmarks such as chromatin condensation, fragmented chromatin were observed in AO/EtBr staining. Moreover, ladder pattern of fragmented DNA observed in DNA gel electrophoresis proved the apoptotic activity of Ceranib 2 in breast cancer cell lines. The apoptotic events were associated with significant increase in the expression of pro-apoptotic genes (Bad, Bax and Bid) and down regulation of anti-apoptotic gene (Bcl 2). Interestingly, increase in sub G1 population of cell cycle phase analysis and elevated Annexin V positive cells after Ceranib 2 treatment substantiated its apoptotic activity in MCF 7 and MDA MB 231 cell lines. Thus, we report Ceranib 2 as a potent therapeutic agent against both ER{sup +} and ER{sup −} breast cancer cell lines. - Highlights: • Acid Ceramidase inhibitor, Ceranib 2 induced apoptosis in Breast cancer cell lines (MCF 7 and MDA MB 231 cell lines). • Apoptosis is mediated by DNA fragmentation and cell cycle arrest. • Ceranib 2 upregulated the expression of pro-apoptotic genes and down regulated anti-apoptotic gene expression. • More potent compared to the standard drug Tamoxifen.

  14. Role of JWA in acute promyelocytic leukemia cell differentiation and apoptosis triggered by retinoic acid, 12-tetradecanoylphorbol-13-acetate and arsenic trioxide

    2002-01-01

    JWA, a cytoskeleton associated gene, was primarily found to be regulated by all trans-retinoic acid (ATRA), 13 cis-retinoic acid (13 cis-RA) and 12-tetradecano- ylphorbol-13-acetate (TPA). Our previous data showed that JWA might be involved in both cellular differentiation and apoptosis induced by several chemicals. In this study, we addressed the possible mechanism of JWA in the regulation of cell differentiation and apoptosis in NB4, a human acute promyelocytic leukemia cell line. CD11b/CD33 expression and cell cycle were analyzed for detecting of cell differentiation and apoptosis. Both reverse-transcription polymerase chain reaction (RT-PCR) and Western blot assays were used for understanding the expressions of JWA. The results showed that under the indicated concentrations ATRA (10?6 mol/L) and As2O3 (10?6 mol/L) induced cell differentiation and apoptosis separately; while both 4HPR (10?6 mol/L) and TPA (10?7 mol/L) showed dual-directional effects on NB4 cells, they not only trigger cells' differentiation but also induce cells apoptosis at the same time. All chemicals up-regulated JWA expression whatever they trigger cells either differentiation or apoptosis; however, it seems that the chemicals have no effect on PML/RAR? in the treated NB4 cells. Anti-sense JWA oligonucleotide could partially block the ability of TPA in inducing cell differentiation and apoptosis via direct signal pathway. Interestingly, a high molecular weight JWA protein (JWAF) was identified only in de novo primary APL cells and it was also responsible for ATRA treatment. It raises questions of whether the JWAF is a novel APL specific marker and, how it was involved in the known mechanism of APL.

  15. Gene Analysis of Arsenic Trioxide—induced Apoptosis of Lymphoma Cells

    ZHANGZidong; LIWeiyu; 等

    2002-01-01

    Objective The effect of arsenic trioxide on apoptosis gene expression of Raji cell was explored when Raji cells were incubated with 0.5μmol/L of arsenic trioxide for 6h。Methods Cell culture,extraction and isolation of mRNA,preparation of probes labeled with fluorescence,hybridization technique of DNA chip(each chip containing 200 apoptosis genes,Chinese Shanghai Biostar,In.)were used.Results Arsenic trioxide induced significant changes in 10%(20/200 genes)of the apoptosis genes:18 genes were downregulated,only two upregulated.In particular,inhibitors of apoptosis protein,such as X-linked inhibitor of apoptosis protein,were significantly downregulated.P53 and the other apoptosis genes were also downregulatec.Of the upregulated genes,high expression of heat-shock protein could promote apoptosis of Raji cells.Conclusion The inhibitors of apoptosis protein play an important role in the process of arsenic trioxide-induced apoptosis of Raji cells.

  16. GNRs@SiO₂-FA in combination with radiotherapy induces the apoptosis of HepG2 cells by modulating the expression of apoptosis-related proteins.

    Gao, Bin; Shen, Lei; He, Ke-Wu; Xiao, Wei-Hua

    2015-11-01

    The aim of the present study was to examine the apoptosis of the hepatocellular carcinoma cell line, HepG2, induced by treatment with folic acid-conjugated silica-coated gold nanorods (GNRs@SiO2-FA) in combination with radiotherapy, and to determine the involvement of apoptosis-related proteins. An MTT colorimetric assay was used to assess the biocompatibility of GNRs@SiO2-FA. The distribution of GNRs@SiO2-FA into the cells was observed using transmission electron microscopy (TEM). HepG2 cells cultured in vitro were divided into the following 4 groups: i)the control group (untreated), ii) the GNRs@SiO2-FA group, iii) the radiotherapy group (iodine 125 seeds) and iv) the combination group (treated with GNRs@SiO2-FA and iodine 125 seeds) groups. The apoptosis of the HepG2 cells was detected by flow cytometry. The concentration range of Ki-67. The combination of GNRs@SiO2-FA and radiotherapy may thus prove to be a new approach in the treatment of primary liver cancer. PMID:26648274

  17. Aminolevulinic acid-based photodynamic therapy induces apoptosis of prematurely senescent fibroblasts induced by ultraviolet B stress%氨基酮戊酸光动力疗法诱导中波紫外线应激性衰老成纤维细胞发生凋亡

    张丽超; 张海荣; 周炳荣; 骆丹; 马立文; 张家安; 王申; 易飞; Maya Valeska Gozali

    2015-01-01

    Objective To study the effect of aminolevulinic acid-based photodynamic therapy (ALA-PDT) on oxidative damage to and apoptosis of prematurely senescent fibroblasts induced by ultraviolet B stress (UVB-SIPS-FB).Methods Both normal fibroblasts and UVB-SIPS-FB were divided into 2-hour and 6-hour groups with the duration of incubation with ALA away from light being 2 and 6 hours respectively,and each group was divided into 7 subgroups:control subgroup receiving no treatment,ALA subgroup treated with ALA alone,red laser group treated with 100 J/cm2 red laser alone,3 ALA-PDT subgroups pretreated with ALA followed by red laser radiation at 25,50 and 100 J/cm2 respectively,NAC + ALA-PDT subgroup sequentially pretreated with ALA and NAC (5 mmol/L) followed by red laser radiation at 50 J/cm2.The wavelength and power density of red laser was 635 nm and 50 mW/cm2 respectively in this study.Fluorescence microscopy and flow cytometry were performed to determine the levels of reactive oxygen species (ROS) and mitochondrial membrane potentials (MMPs),and Hoechst staining and flow cytometry to detect cell apoptosis.Statistical analysis was carried out with the software SPSS 13.0 by one-way analysis of variance (ANOVA) and q test.Results The apoptosis rate of UVB-SIPS-FB was significantly higher in the 25-,50-,100-J/cm2 ALA-PDT subgroups (2-hour group:7.34% ± 0.87%,8.39% ± 1.16% and 17.03% ± 1.29% vs.3.81% ± 0.59%,F=102.70,P< 0.05;6-hour group:13.85% ± 1.71%,23.40% ± 2.14% and 41.02% ± 2.73% vs.5.09% ± 1.64%,F=106.00,P < 0.05) than in the control subgroups,but lower in the NAC + ALA-PDT subgroups (2-hour group:5.35% ± 0.58%,6-hour group:9.97% ± 3.23%,both P < 0.05) than in the 50-J/cm2 ALA-PDT subgroups.There was no significant difference in the apoptosis rate of UVB-SIPS-FB between the ALA subgroups or red laser subgroups and control subgroups.ALA-PDT subgroups showed significantly increased ROS level and MMP,and the degree of

  18. ELDEPRYL AND RILUZOLE INHIBIT 1-METHYL-4-PHENYL -1,2,3,6-TETRAHYDROPYRIDINE (MPTP)-INDUCED NIGRAL NEURONAL APOPTOSIS IN MICE

    陈生弟; 郭明; 刘振国; 陈红专

    2002-01-01

    Objective To investigate the possible role of apoptosis in the pathogenesis of Parkinsons disease. Methods C57BL mice were treated with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine(MPTP), and TUNEL and flow cytometry were employed to detect neuronal apoptosis in the substantia nigra. ResultsThe results of animal experiment demonstrated that the administration of MPTP 30mg/kg for 7d could induce neuronal apoptosis in the substantia nigra. The MPTP-induced nigral neuronal apoptosis could be completely prevented by pre-treatment of Eldepryl, an inhibitor of B typed monoamine oxidase (MAO-B);and partially protected by pre-treatment of Riluzole, an antagonist of excitatory amino acid receptors. Data of cell culture experiment showed that 20mmol 1-methyl-4-phenylpyridinium ion(MPP+) induced the apoptosis of pheochromocytoma(PC12 cells), whereas 20mmol MPTP did not cause PC12 cells apoptosis. Conclusion It is concluded that the apoptotic effect of MPTP in vivo on the nigral neurons may be mediated by its intermediate metabolite MPP+. The dopaminergic neuronal apoptosis in the substantia nigra may be a common pathway of various causes that lead to the onset of Parkinson's disease.

  19. Overcoming Hypoxic-Resistance of Tumor Cells to TRAIL-Induced Apoptosis through Melatonin

    You-Jin Lee

    2014-07-01

    Full Text Available A solid tumor is often exposed to hypoxic or anoxic conditions; thus, tumor cell responses to hypoxia are important for tumor progression as well as tumor therapy. Our previous studies indicated that tumor cells are resistant to tumor necrosis factor-related apoptosis-inducing ligand (TRAIL-induced cell apoptosis under hypoxic conditions. Melatonin inhibits cell proliferation in many cancer types and induces apoptosis in some particular cancer types. Here, we examined the effects of melatonin on hypoxic resistant cells against TRAIL-induced apoptosis and the possible mechanisms of melatonin in the hypoxic response. Melatonin treatment increased TRAIL-induced A549 cell death under hypoxic conditions, although hypoxia inhibited TRAIL-mediated cell apoptosis. In a mechanistic study, hypoxia inducible factor-1α and prolyl-hydroxylase 2 proteins, which increase following exposure to hypoxia, were dose-dependently down-regulated by melatonin treatment. Melatonin also blocked the hypoxic responses that reduced pro-apoptotic proteins and increased anti-apoptotic proteins including Bcl-2 and Bcl-xL. Furthermore, melatonin treatment reduced TRAIL resistance by regulating the mitochondrial transmembrane potential and Bax translocation. Our results first demonstrated that melatonin treatment induces apoptosis in TRAIL-resistant hypoxic tumor cells by diminishing the anti-apoptotic signals mediated by hypoxia and also suggest that melatonin could be a tumor therapeutic tool by combining with other apoptotic ligands including TRAIL, particularly in solid tumor cells exposed to hypoxia.

  20. Effect of Retinoic Acid on Apoptosis and Expression of Fas Proteins in Mouse Blastocysts Cultured In Vitro

    Yan'e XIONG; Duanlian ZHANG

    2008-01-01

    Mouse blastocysts were exposed to doses of 0,1 and 10μmol/L retinoic acid (RA) for 24h and the cytotoxic effect of RA on the mouse blastocysts in vitro was observed. FITC-labeled terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL-FITC) assay was employed to stain apoptotic cells and immunohistochemical S-P staining method was used to detect the expression of Fas protein in mouse blastocysts in vitro. The results showed that RA could induce apoptosis and increase the expression of Fas proteins of trophectoderm (TE) and inner cell mass (ICM) cells in blastocysts. Compared with the findings for the control blastocysts, exposure to RA (10μmol/L) resulted in a more significant apoptosis and higher expression level of Fas proteins (P<0.01). It was concluded that RA could induce apoptosis, which may result in a significant reduction in the average number of total cells and the trophectoderm/inner cell mass in blastocysts and an increased expression of Fas protein, suggesting that RA had a cytotoxic effect on the growth and development of early embryos in mice.

  1. Thiazole antibiotic thiostrepton synergize with bortezomib to induce apoptosis in cancer cells.

    Bulbul Pandit

    Full Text Available Thiazole antibiotic, thiostrepton was recently identified as proteasome inhibitor. We investigated the therapeutic potential of the combination of thiostrepton and proteasome inhibitor bortezomib (Velcade on various human tumor cell lines. Combination of sub-lethal concentrations of thiostrepton and bortezomib induced potent apoptosis and inhibition of long-term colony formation in a wide variety of human cancer cell lines. The synergistic relationship between thiostrepton and bortezomib combination was also quantitatively demonstrated by calculating their combination index values that were much lower than 1 in all studied cell lines. The synergy between these drugs was based on their proteasome inhibitory activities, because thiostrepton modification, thiostrepton methyl ester, which did not have intact quinaldic acid ring and did not inhibit proteasome activity failed to demonstrate any synergy in combination with bortezomib.

  2. Ultrasonication processed Panax ginseng berry extract induces apoptosis through an intrinsic apoptosis pathway in HepG2 cells.

    Jung, Hyunwoo; Bae, Jinhyung; Ko, Sung Kwon; Sohn, Uy Dong

    2016-06-01

    Ginseng's major active components, ginsenosides, have been known to show anti-cancer, neuroprotective, and anti-inflammatory activities. Ultrasonication processed Panax ginseng berry extract (UGB) contains various ginsenosides. The components are different from Panax ginseng berry extract (GBE). This study was aimed to investigate the cytotoxic mechanism of UGB in HepG2 cells, human hepatocellular carcinoma cell line. HepG2 cells were treated with UGB (0, 10, 20 μg/ml). Cell growth and cellular apoptosis were evaluated by MTT assay and Annexin V/Pi staining, respectively. Intracellular Reactive oxygen species (ROS) levels were also determined by 2', 7'-dichlorofluorescin diacetate (DCFDA) staining. The expressions of Bax, Bcl-2 and caspase-3, the apoptotic markers, were evaluated by Western Blot. UGB dose-dependently inhibited cell growth and induced apoptotic cell death. Intracellular ROS levels were increased. UGB increased the expression of the cleaved form of caspase-3. Furthermore, UGB induced apoptosis of HepG2 cells through Bax activation and Bcl-2 inhibition. In conclusion, UGB induced apoptosis through an intrinsic pathway in HepG2 cells suggesting that UGB might play a role as a novel substance for anti-cancer effect. PMID:27233905

  3. Knockdown of Akt Sensitizes Osteosarcoma Cells to Apoptosis Induced by Cisplatin Treatment

    Changwei Yang; Yushu Bai; Guoyou Zhang; Xiaodong Zhu; Ming Li

    2011-01-01

    Akt plays an important role in the inhibition of apoptosis induced by chemotherapy and other stimuli. We therefore investigated if knockdown of Akt2 promoted drug-induced apoptosis in cultured osteosarcoma cells in vitro. SAOS-2 cells were transfected with Akt2 siRNA. The sensitivity of the transformed cell line to the chemotherapeutic drug cisplatin was assessed. Reduced expression of Akt2 did not directly inhibit the growth rate of the transfected cells; however, it significantly increased ...

  4. Molecular Regulation of DNA Damage-Induced Apoptosis in Neurons of Cerebral Cortex

    Martin, Lee J.; Liu, Zhiping; Pipino, Jacqueline; Chestnut, Barry; Landek, Melissa A.

    2008-01-01

    Cerebral cortical neuron degeneration occurs in brain disorders manifesting throughout life, but the mechanisms are understood poorly. We used cultured embryonic mouse cortical neurons and an in vivo mouse model to study mechanisms of DNA damaged-induced apoptosis in immature and differentiated neurons. p53 drives apoptosis of immature and differentiated cortical neurons through its rapid and prominent activation stimulated by DNA strand breaks induced by topoisomerase-I and -II inhibition. B...

  5. Time-dependent changes of autophagy and apoptosis in lipopolysaccharide-induced rat acute lung injury

    Li Lin; Lijun Zhang; Liangzhu Yu; Lu Han; Wanli Ji; Hui Shen; Zhenwu Hu

    2016-01-01

    Objective(s): Abnormal lung cell death including autophagy and apoptosis is the central feature in acute lung injury (ALI). To identify the cellular mechanisms and the chronology by which different types of lung cell death are activated during lipopolysaccharide (LPS)-induced ALI, we decided to evaluate autophagy (by LC3-II and autophagosome) and apoptosis (by caspase-3) at different time points after LPS treatment in a rat model of LPS-induced ALI. Materials and Methods: Sprague-Dawley ra...

  6. Influence of radiation-induced apoptosis on development brain in molecular regulation

    An outline of current status on the influence of radiation on the development brain was given. Some genes as immediate early gene, Bcl-2 family, p53, heat shock protein and AT gene play an important regulation role in ionizing radiation-induced development brain cells apoptosis. And such biological factor as nerve growth factor, interleukin-1, tumor necrosis factor, basic fibroblast growth factor, transforming growth factor and so on have a vital protection function against ionizing radiation-induced cells apoptosis

  7. High-neurovirulence GDVII virus induces apoptosis in murine astrocytes through tumor necrosis factor (TNF)-receptor and TNF-related apoptosis-inducing ligand

    We carried out a study to determine if the high-neurovirulence GDVII strain of Theiler's murine encephalomyelitis virus (TMEV) and the demyelinating, low-neurovirulence BeAn strain induced apoptosis in murine astrocytes. Astrocytes, the major glial cell population of the central nervous system, were semipermissive for GDVII virus replication. Programmed cell death, demonstrated by apoptosis-specific caspase-3 protease activity, was maximal 8 h after GDVII infection at an m.o.i. of 1. Purified TMEV capsid proteins VP1, VP2, and VP3 did not induce apoptosis but antibodies to VP1 and VP2 inhibited it. Antibody inhibition of caspase-3 activity as well as flow cytometry experiments implicated TNF-related apoptosis-inducing ligand (TRAIL) and TNF-α-receptor (TNF-R) in apoptosis signaling. Converselly, TNF-α and the TRAIL-receptor were not upregulated. Furthermore, the number of functional TNF-α receptors, but not their affinity, was increased in apoptotic GDVII virus-infected astrocytes, as confirmed in binding experiments with 125I-labeled recombinant murine TNF-α. In vivo studies showed that most of the cells loaded with the virus when injected in the brains of SJL mice were neurons but very few showed TUNEL costaining. Conversely, many of the apoptotic cells found were also positive for GFAP staining

  8. Naringin prevents ovariectomy-induced osteoporosis and promotes osteoclasts apoptosis through the mitochondria-mediated apoptosis pathway

    Highlights: • Naringin possesses many pharmacological activities, promotes the proliferation of osteoblast. • Undecalcified histological obtain dynamic parameters of callus formation and remodeling. • Naringin regulate osteoclast apoptosis by mitochondrial pathway. - Abstract: Naringin, the primary active compound of the traditional Chinese medicine Rhizoma drynariae, possesses many pharmacological activities. The present study is an effort to explore the anti-osteoporosis potential of naringin in vivo and in vitro. In vivo, we used ovariectomized rats to clarify the mechanisms by which naringin anti-osteoporosis. In vitro, we used osteoclasts to investigate naringin promotes osteoclasts apoptosis. Naringin was effective at enhancing BMD, trabecular thickness, bone mineralization, and mechanical strength in a dose-dependent manner. The result of RT-PCR analysis revealed that naringin down-regulated the mRNA expression levels of BCL-2 and up-regulated BAX, caspase-3 and cytochrome C. In addition, naringin significantly reduced the bone resorption area in vitro. These findings suggest that naringin promotes the apoptosis of osteoclasts by regulating the activity of the mitochondrial apoptosis pathway and prevents OVX-induced osteoporosis in rats

  9. Naringin prevents ovariectomy-induced osteoporosis and promotes osteoclasts apoptosis through the mitochondria-mediated apoptosis pathway

    Li, Fengbo [Tianjin Institute of Orthopedics in Traditional Chinese and Western Medicine, No. 155, Munan Road, Tianjin TJ 300050 (China); Graduate School of Tianjin Medical University, No. 22, Qixiangtai Street, Heping District, Tianjin 300070 (China); Sun, Xiaolei; Ma, Jianxiong [Tianjin Institute of Orthopedics in Traditional Chinese and Western Medicine, No. 155, Munan Road, Tianjin TJ 300050 (China); Ma, Xinlong, E-mail: gengxiao502@163.com [Tianjin Institute of Orthopedics in Traditional Chinese and Western Medicine, No. 155, Munan Road, Tianjin TJ 300050 (China); Zhao, Bin; Zhang, Yang; Tian, Peng [Tianjin Institute of Orthopedics in Traditional Chinese and Western Medicine, No. 155, Munan Road, Tianjin TJ 300050 (China); Li, Yanjun [Graduate School of Tianjin Medical University, No. 22, Qixiangtai Street, Heping District, Tianjin 300070 (China); Han, Zhe [Tianjin Institute of Orthopedics in Traditional Chinese and Western Medicine, No. 155, Munan Road, Tianjin TJ 300050 (China)

    2014-09-26

    Highlights: • Naringin possesses many pharmacological activities, promotes the proliferation of osteoblast. • Undecalcified histological obtain dynamic parameters of callus formation and remodeling. • Naringin regulate osteoclast apoptosis by mitochondrial pathway. - Abstract: Naringin, the primary active compound of the traditional Chinese medicine Rhizoma drynariae, possesses many pharmacological activities. The present study is an effort to explore the anti-osteoporosis potential of naringin in vivo and in vitro. In vivo, we used ovariectomized rats to clarify the mechanisms by which naringin anti-osteoporosis. In vitro, we used osteoclasts to investigate naringin promotes osteoclasts apoptosis. Naringin was effective at enhancing BMD, trabecular thickness, bone mineralization, and mechanical strength in a dose-dependent manner. The result of RT-PCR analysis revealed that naringin down-regulated the mRNA expression levels of BCL-2 and up-regulated BAX, caspase-3 and cytochrome C. In addition, naringin significantly reduced the bone resorption area in vitro. These findings suggest that naringin promotes the apoptosis of osteoclasts by regulating the activity of the mitochondrial apoptosis pathway and prevents OVX-induced osteoporosis in rats.

  10. Microcystin-LR induced developmental toxicity and apoptosis in zebrafish (Danio rerio) larvae by activation of ER stress response.

    Qi, Mei; Dang, Yao; Xu, Qinglong; Yu, Liqin; Liu, Chunsheng; Yuan, Yongchao; Wang, Jianghua

    2016-08-01

    Recent studies have demonstrated that cyanobacteria-derived Microcystin-LR (MC-LR) can cause developmental toxicity and trigger apoptosis in zebrafish (Danio rerio) larvae, but the underlying mechanisms remain largely unknown. In this study, we tested the hypothesis that the mechanism by which MC-LR induces developmental toxicity is through activation of endoplasmic reticulum (ER) stress. MC-LR (4.0 μM) exposure through submersion caused serious developmental toxicity, such as malformation, growth delay and decreased heart rates in zebrafish larvae, which could be inhibited by ER stress blocker, tauroursodeoxycholic acid (TUDCA, 20 μM). Meanwhile, acridine orange (AO) staining showed TUDCA could rescue cell apoptosis in heart area in zebrafish larvae resulted by MC-LR exposure. Real-time polymerase chain reaction (real-time PCR) analysis demonstrated that MC-LR induced activation of ER stress which consequently triggered apoptosis in zebrafish larvae. Protein expression examined by western blot indicated that MC-LR could activate MAPK8/Bcl-2/Bax pathway and caspase-dependent apoptotic pathway in zebrafish larva and the effects were mitigated by inhibition of ER stress. Taken together, the results observed in this study suggested that ER stress plays a critical role in developmental toxicity and apoptosis in zebrafish embryos exposed to MC-LR. PMID:27219292

  11. TIMP-1 gene deficiency increases tumour cell sensitivity to chemotherapy-induced apoptosis

    Davidsen, Marie Louise; Würts, S.Ø.; Rømer, Maria Unni Koefoed;

    2006-01-01

    gene deficiency increases the response to chemotherapy considerably, confirming that TIMP-1 protects the cells from apoptosis. This is to our knowledge the first study investigating TIMP-1 and chemotherapy-induced apoptosis employing a powerful model system comprising TIMP-1 gene-deficient cells and...... this hypothesis, we have established TIMP-1 gene-deficient and TIMP-1 wild-type fibrosarcoma cells from mouse lung tissue. We have characterised these cells with regard to TIMP-1 genotype, TIMP-1 expression, malignant transformation and sensitivity to chemotherapy-induced apoptosis. We show that TIMP-1...

  12. TAT-apoptin is efficiently delivered and induces apoptosis in cancer cells.

    Guelen, Lars; Paterson, Hugh; Gäken, Joop; Meyers, Michelle; Farzaneh, Farzin; Tavassoli, Mahvash

    2004-02-01

    Apoptin has been described to induce apoptosis in various human cancer cell lines, but not in normal cells, thus making it an interesting candidate for the development of novel therapeutic strategies. Apoptin was generated and cloned into several mammalian expression vectors. Transfection or microinjection of apoptin cDNA resulted in its expression, initially in the cytoplasm with a filamentous pattern. Subsequently, apoptin entered the nucleus and efficiently induced apoptosis in several cancer cell lines. Nuclear localization was shown to be required for induction of apoptosis. Apoptin expression level was found to be an important determinant of the efficiency of induction of apoptosis. Surprisingly, expression of apoptin or GFP-apoptin cDNA induced apoptosis in some normal cells. When fused to the HIV-TAT protein transduction domain and delivered as a protein, TAT-apoptin was transduced efficiently (>90%) into normal and tumour cells. However, TAT-apoptin remained in the cytoplasm and did not kill normal 6689 and 1BR3 fibroblasts. In contrast TAT-apoptin migrated from the cytoplasm to the nucleus of Saos-2 and HSC-3 cancer cells resulting in apoptosis after 24 h. This study shows that apoptin is a powerful apoptosis-inducing protein with a potential for cancer therapy. PMID:14691460

  13. Latent membrane protein 1 inhibits apoptosis induced by 60 irradiation via Survivin triggering signal-pathway

    Objective: To investigate the anti-apoptosis mechanism of EB virus encoden latent membrane protein 1 (LMP1) via the survivin signal transduction pathway after irradiation induction. Methods: Tet-on- LMP1 HNE2 cells, as a model, were detected with morphological assay, flowcytometry and Caspase 3 assay after 60Co irradiation with LMP1 induced by doxycycline. The apoptosis in the anti-sense survivin transfected cells was tested. Results: The results showed that, with LMP1 expression, the apoptosis rates from morphological assay and flowcytometry were 32.7%±2.1% and 6.3%, which showed that they were all lower than that without LMP1 expression (66.0%±3.0% and 29.6%). When anti-sense of survivin was induced, the apoptosis rates were 59.0%±3.2% and 3.0% respectively, and caspase 3 activity was 3.78 nmol/106 cells, which were higher than that of the control (26.0%±2.6%, 8.6% and 2.79 nmol/106). Survivin restrained the cell apoptosis induced by irradiation, but anti-sense of survivin could release this inhibition of cell apoptosis triggered by LMP1 expression. Conclusion: LMP1 inhibits the irradiation-induced cell apoptosis via triggering survivin expression. Survivin may be targeted in some certain therapy

  14. A novel chenodeoxycholic derivative HS-1200 enhances radiation-induced apoptosis in human MCF-7 breast cancer cells

    To examine whether a synthetic bile acid derivatives (HS-1200) sensitizes the radiation-induced apoptosis in human breast cancer cells (MCF-7) and to investigate the underlying mechanism. Human breast cancer cells (MCF-7) in exponential growth phase were treated with HS-1200 for 24 hours at 37 .deg. C with 5% CO2 in air atmosphere. After removal of HS-1200, cells were irradiated with 2 ∼ 8 Gy X-ray, and then cultured in drug-free media for 24-96 hours. The effect of radiation on the clonogenicity of MCF-7 cells was determined with clonogenic cell survival assay with 16 μ M of HS-1200. The induction of apoptosis was determined using agarose gel electrophoresis and Hoechst staining. The expression level of apoptosis-related molecules, such as PARP, Bax, Bcl-2, Bak and AIF, were assayed by Western blotting analysis with 40 μ M of HS-1200 combined with 8 Gy irradiation. To examine the cellular location of cytochrome c, bax and AIF immunofluorescent stainings were undertaken. Treatment of MCF-7 cells with 40 μ M of HS-1200 combined with 8 Gy irradiation showed several changes associated with enhanced apoptosis by agarose gel electrophoresis and Hoechst staining. HS-1200 combined with 8 Gy irradiation treatment also enhanced production of PARP cleavage products and increased Bax/Bcl-2 ratio by Western blotting. Loss of mitochondrial membrane potential (Δ ψ m) and increased cytochrome c staining indicated that cytochrome c had been released from the mitochondria in HS-1200 treated cells. We demonstrated that combination treatment with a synthetic chenodeoxycholic acid derivative HS-1200 and irradiation enhanced radiation-induced apoptosis of human breast cancer cells (MCF-7). We suggest that the increased Bax/Bcl-2 ratio in HS-1200 co-treatment group underlies the increased radiosensitivity of MCF-7 cells. Further futures studies are remained elusive

  15. Denbinobin induces apoptosis in human lung adenocarcinoma cells via Akt inactivation, Bad activation, and mitochondrial dysfunction.

    Kuo, Chen-Tzu; Hsu, Ming-Jen; Chen, Bing-Chang; Chen, Chien-Chih; Teng, Che-Ming; Pan, Shiow-Lin; Lin, Chien-Huang

    2008-02-28

    Increasing evidence demonstrated that denbinobin, isolated from Ephemerantha lonchophylla, exert cytotoxic effects in cancer cells. The purpose of this study was to investigate whether denbinobin induces apoptosis and the apoptotic mechanism of denbinobin in human lung adenocarcinoma cells (A549). Denbinobin (1-20microM) caused cell death in a concentration-dependent manner. Flow cytometric analysis and annexin V labeling demonstrated that denbinobin increased the percentage of apoptotic cells. A549 cells treated with denbinobin showed typical characteristics of apoptosis including morphological changes and DNA fragmentation. Denbinobin induced caspase 3 activation, and N-benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone (zVAD-fmk), a broad-spectrum caspase inhibitor, prevented denbinobin-induced cell death. Denbinobin induced the loss of the mitochondrial membrane potential and the release of mitochondrial apoptotic proteins including cytochrome c, second mitochondria derived activator of caspase (Smac), and apoptosis-inducing factor (AIF). In addition, denbinobin-induced Bad activation was accompanied by the dissociation of Bad with 14-3-3 and the association of Bad with Bcl-xL. Furthermore, denbinobin induced Akt inactivation in a time-dependent manner. Transfection of A549 cells with both wild-type and constitutively active Akt significantly suppressed denbinobin-induced Bad activation and cell apoptosis. These results suggest that Akt inactivation, followed by Bad activation, mitochondrial dysfunction, caspase 3 activation, and AIF release, contributes to denbinobin-induced cell apoptosis. PMID:18262737

  16. Radiation induced apoptosis and initial DNA damage are inversely related in locally advanced breast cancer patients

    Rodriguez-Gallego Carlos

    2010-09-01

    Full Text Available Abstract Background DNA-damage assays, quantifying the initial number of DNA double-strand breaks induced by radiation, have been proposed as a predictive test for radiation-induced toxicity. Determination of radiation-induced apoptosis in peripheral blood lymphocytes by flow cytometry analysis has also been proposed as an approach for predicting normal tissue responses following radiotherapy. The aim of the present study was to explore the association between initial DNA damage, estimated by the number of double-strand breaks induced by a given radiation dose, and the radio-induced apoptosis rates observed. Methods Peripheral blood lymphocytes were taken from 26 consecutive patients with locally advanced breast carcinoma. Radiosensitivity of lymphocytes was quantified as the initial number of DNA double-strand breaks induced per Gy and per DNA unit (200 Mbp. Radio-induced apoptosis at 1, 2 and 8 Gy was measured by flow cytometry using annexin V/propidium iodide. Results Radiation-induced apoptosis increased in order to radiation dose and data fitted to a semi logarithmic mathematical model. A positive correlation was found among radio-induced apoptosis values at different radiation doses: 1, 2 and 8 Gy (p Conclusions An inverse association was observed for the first time between these variables, both considered as predictive factors to radiation toxicity.

  17. Cell wall dynamics modulate acetic acid-induced apoptotic cell death of Saccharomyces cerevisiae

    António Rego

    2014-08-01

    Full Text Available Acetic acid triggers apoptotic cell death in Saccharomyces cerevisiae, similar to mammalian apoptosis. To uncover novel regulators of this process, we analyzed whether impairing MAPK signaling affected acetic acid-induced apoptosis and found the mating-pheromone response and, especially, the cell wall integrity pathways were the major mediators, especially the latter, which we characterized further. Screening downstream effectors of this pathway, namely targets of the transcription factor Rlm1p, highlighted decreased cell wall remodeling as particularly important for acetic acid resistance. Modulation of cell surface dynamics therefore emerges as a powerful strategy to increase acetic acid resistance, with potential application in industrial fermentations using yeast, and in biomedicine to exploit the higher sensitivity of colorectal carcinoma cells to apoptosis induced by acetate produced by intestinal propionibacteria.

  18. Berberine potentizes apoptosis induced by X-rays irradiation probably through modulation of gap junctions

    LIU Bing; WANG Qin; YUAN Dong-dong; HONG Xiao-ting; TAO Liang

    2011-01-01

    Background Clinical combination of some traditional Chinese medical herbs, including berberine, with irradiation is demonstrated to improve efficacy of tumor radiotherapy, yet the mechanisms for such effect remain largely unknown. The present study investigated the effect of berberine on apoptosis induced by X-rays irradiation and the relation between this effect and gap junction intercellular communication (GJIC).Methods The role of gap junctions in the modulation of X-rays irradiation-induced apoptosis was explored by manipulation of connexin (Cx) expression, and gap junction function, using oleamide, a GJIC inhibitor, and berberine.Results In transfected HeLa cells, Cx32 expression increased apoptosis induced by X-rays irradiation, while inhibition of gap junction by oleamide reduced the irradiation responses, indicating the dependence of X-rays irradiation-induced apoptosis on GJIC. Berberine, at the concentrations without cytotoxicity, enhanced apoptosis induced by irradiation only in the presence of functional gap junctions.Conclusions These results suggest that berberine potentizes cell apoptosis induced by X-rays irradiation, probably through enhancement of gap junction activity.

  19. Identification of genes regulating TRAIL-induced apoptosis in rheumatoid arthritis fibroblasts-like synoviocytes.

    Audo, R; Hegglin, A; Severac, D; Dantec, C; Combe, B; Hahne, M; Morel, J

    2015-10-01

    We previously described that sensitivity to tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-induced apoptosis varied in rheumatoid arthritis fibroblasts-like synoviocytes (RAFLS) from one patient to another and was correlated with disease severity. Therefore, we screened for genes differentially expressed in RAFLS sensitive and resistant to TRAIL-induced apoptosis. The sensitivity of RAFLS was defined based on the percentage of TRAIL-induced apoptosis: 0-10% for resistant cells and >25% for sensitive RAFLS. We performed transcriptomic comparison between RAFLS-S (n=6) and RAFLS-R (n=6) and then examined the implication of identified candidates in the regulation of apoptosis using small interference RNA (siRNA). Microarray analysis revealed 10 functional genes differentially expressed according to TRAIL sensitivity. These factors are implicated in different functions, such as the respiratory chain (ND3), the transport of lipids (OSBP2, PLTP), the regulation of signaling linked to extracellular factors (SULF2, GALNT1, SIAE) or the regulation of gene expression (TET2 and LARP6). We confirmed differential expression for GALNT1 and LARP6 by quantitative reverse transcriptase-PCR. Using siRNA extinction, we demonstrated the implication of GALNT1, SULF2 and LARP6 in the control of TRAIL-induced responses. These results are of particular interest as GALNT1 and LARP6 have been implicated in the regulation of cell death and may represent interesting targets to induce apoptosis of RAFLS. PMID:26247836

  20. Milk fermented by Propionibacterium freudenreichii induces apoptosis of HGT-1 human gastric cancer cells.

    Fabien J Cousin

    Full Text Available BACKGROUND: Gastric cancer is one of the most common cancers in the world. The "economically developed countries" life style, including diet, constitutes a risk factor favoring this cancer. Diet modulation may lower digestive cancer incidence. Among promising food components, dairy propionibacteria were shown to trigger apoptosis of human colon cancer cells, via the release of short-chain fatty acids acetate and propionate. METHODOLOGY/PRINCIPAL FINDINGS: A fermented milk, exclusively fermented by P. freudenreichii, was recently designed. In this work, the pro-apoptotic potential of this new fermented milk was demonstrated on HGT-1 human gastric cancer cells. Fermented milk supernatant induced typical features of apoptosis including chromatin condensation, formation of apoptotic bodies, DNA laddering, cell cycle arrest and emergence of a subG1 population, phosphatidylserine exposure at the plasma membrane outer leaflet, reactive oxygen species accumulation, mitochondrial transmembrane potential disruption, caspase activation and cytochrome c release. Remarkably, this new fermented milk containing P. freudenreichii enhanced the cytotoxicity of camptothecin, a drug used in gastric cancer chemotherapy. CONCLUSIONS/SIGNIFICANCE: Such new probiotic fermented milk may thus be useful as part of a preventive diet designed to prevent gastric cancer and/or as a food supplement to potentiate cancer therapeutic treatments.

  1. 冬凌草甲素联合丙戊酸钠对HL-60细胞的生长抑制和诱导凋亡作用研究%Growth inhibition and apoptosis induced by oridonin combined with valproic acid in HL-60 cells

    邹慧娟; 姜国胜

    2011-01-01

    Objective To investigate the apoptosis-inducing effect of oridonin combined with valproic acid( VPA)on leukemic cell line HL-60,and study the feasibility of oridonin combined with VPA to be used in clinical practice. Methods Oridonin of 6-12 μmol/L combined with VPA of 0. 5-1 mmol/L were added in exponential growth HL-60 cells respectively. Cell count assays were used to measure the growth inhibitory effect of oridonin combined with VPA or alone. Flow cytometry was used to evaluate apoptosis with Annexin V and propidium iodide (PI) double staining. Results Combined use of oridonin and VPA could synergistically inactivate HL-60 cells,and inhibit the cell proliferation and induce apoptosis in a dose-and time-dependent manner (P < 0.05 ). Conclusion Oridonin has a synergistic effect combined with VPA. Oridonin has a promising prospect in clinical use of leukemia.%目的 研究中药单体冬凌草甲素(ORI)联合组蛋白去乙酰化酶抑制剂丙戊酸钠(VPA)诱导急性早幼粒白血病细胞株HL-60凋亡,探讨其应用于临床的可行性.方法 在对数生长期的HL-60细胞中分别加入6~12 la,mol/L的ORI和0.5~1 mmol/L的VPA,采用细胞计数法测定ORI和VPA单独和联合应用时对细胞的生长抑制,并用Annexin V/PI双标法流式细胞术检测细胞凋亡.结果 ORI联合VPA可协同降低HL-60细胞活力,抑制细胞增殖,诱导细胞凋亡,比单独用药凋亡作用更为显著(P<0.05).结论 ORI和VPA具有协同作用,能高效杀灭白血病细胞.ORI和VPA是一种有望应用于白血病临床治疗的新型生物制剂.

  2. Detection of radiation-induced apoptosis using the comet assay

    The electrophoresis pattern of apoptotic cells detected by the comet assay has a characteristic small head and spread tail. This image has been referred to as an apoptotic comet, but it has not been previously proven to be apoptotic cells by any direct method. In order to identify this image obtained by the comet assay as corresponding to an apoptotic cell, the frequency of appearance of apoptosis was examined using CHO-K1 and L5178Y cells which were exposed to gamma irradiation. As a method for detecting apoptosis, the terminal deoxynucleotidyl transferase mediated dUTP nick end labeling (TUNEL) assay was used. When the frequency of appearance of apoptotic cells following gamma irradiation was observed over a period of time, there was a significant increase in appearance of apoptosis when using the TUNEL assay. However, there was only a slight increase when using the comet assay. In order to verify the low frequency of appearance of apoptosis when using the comet assay, we attempted to use the TUNEL assay to satin the apoptotic comets detected in the comet assay. The apoptotic comets were TUNEL positive and the normal comets were TUNEL negative. This indicates that the apoptotic comets were formed from DNA fragments with 3'-hydroxy ends that are generated as cells undergo apoptosis. Therefore, it was understood that the characteristic pattern of apoptotic comets detected by the comet assay corresponds to cells undergoing apoptosis. (author)

  3. Sulindac induces apoptosis and protects against colon carcinoma in mice

    Bao-Cun Sun; Xiu-Lan Zhao; Shi-Wu Zhang; Yi-Xin Liu; Lan Wang; Xin Wang

    2005-01-01

    AIM: To study the effect of sulindac on colon cancer induction in mice.METHODS: The chemo-preventive action of 80 ppm sulindac fed during initiation and post-initiation and 100 ppm sulindac fed during progressive stages of induction of colon carcinogenesis in mice was investigated using 1,2-dimethylhydrazine (DMH). Using the terminal deoxynucleotidyltransferase-mediated dUTP nick-end labeling (TUNEL)technique and PCNA immunohistochemical staining, we observed the apoptotic and proliferative cell density changes at different carcinogenic stages and the effect of sulindac on these two phenomena.RESULTS: Dietary sulindac significantly inhibited the incidence of colonic neoplasmas in mice. Compared with the control group, feeding sulindac during initiation and post-initiation stages inhibited the incidence by 46.7-50.4%,and feeding sulindac during progressive stages inhibited the incidence by 41.1%. Animals that were fed sulindac showed less serious pathological changes than those that were fed the control diet (P<0.01, H= 33.35). There was no difference in the density of proliferating cells among those groups which were or were not fed sulindac. In the same period, feeding sulindac resulted in a higher density of apoptotic cells than feeding control diet. CONCLUSION: Sulindac has an anti-carcinogenic function in mice. Its effect on preventing colon carcinogenesis is better than its effect on treating established tumors. By inducing apoptosis, sulindac inhibited the development of colon cancer and delayed canceration. Sulindac has no effect on proliferation. The anti-carcinogenic properties of sulindac are most effective in the moderate and severe stages of dysplasia and canceration.

  4. 15d-PGJ2 induces apoptosis of mouse oligodendrocyte precursor cells

    Reeves Steven A

    2007-07-01

    Full Text Available Abstract Background Prostaglandin (PG production is associated with inflammation, a major feature in multiple sclerosis (MS that is characterized by the loss of myelinating oligodendrocytes in the CNS. While PGs have been shown to have relevance in MS, it has not been determined whether PGs have a direct effect on cells within the oligodendrocyte lineage. Methods Undifferentiated or differentiated mouse oligodendrocyte precursor (mOP cells were treated with PGE2, PGF2α, PGD2 or 15-deoxy-Δ12,14-PGJ2 (15d-PGJ2. Cell growth and survival following treatment were examined using cytotoxicity assays and apoptosis criteria. The membrane receptors for PGD2 and the nuclear receptor peroxisome proliferator-activated receptor (PPARγ, as well as reactive oxygen species (ROS in the death mechanism were examined. Results PGE2 and PGF2α had minimal effects on the growth and survival of mOP cells. In contrast, PGD2 and 15d-PGJ2 induced apoptosis of undifferentiated mOP cells at relatively low micromolar concentrations. 15d-PGJ2 was less toxic to differentiated mOP cells. Apoptosis was independent of membrane receptors for PGD2 and the nuclear receptor PPARγ. The cytotoxicity of 15d-PGJ2 was associated with the production of ROS and was inversely related to intracellular glutathione (GSH levels. However, the cytotoxicity of 15d-PGJ2 was not decreased by the free radical scavengers ascorbic acid or α-tocopherol. Conclusion Taken together, these results demonstrated that 15d-PGJ2 is toxic to early stage OP cells, suggesting that 15d-PGJ2 may represent a deleterious factor in the natural remyelination process in MS.

  5. TGEV nucleocapsid protein induces cell cycle arrest and apoptosis through activation of p53 signaling

    Ding, Li [College of Veterinary Medicine, Northwest A and F University, Yangling, Shaanxi 712100 (China); College of Life Sciences, Hainan Normal University, Haikou, Hainan 571158 (China); Huang, Yong; Du, Qian; Dong, Feng; Zhao, Xiaomin; Zhang, Wenlong; Xu, Xingang [College of Veterinary Medicine, Northwest A and F University, Yangling, Shaanxi 712100 (China); Tong, Dewen, E-mail: dwtong@nwsuaf.edu.cn [College of Veterinary Medicine, Northwest A and F University, Yangling, Shaanxi 712100 (China)

    2014-03-07

    Highlights: • TGEV N protein reduces cell viability by inducing cell cycle arrest and apoptosis. • TGEV N protein induces cell cycle arrest and apoptosis by regulating p53 signaling. • TGEV N protein plays important roles in TGEV-induced cell cycle arrest and apoptosis. - Abstract: Our previous studies showed that TGEV infection could induce cell cycle arrest and apoptosis via activation of p53 signaling in cultured host cells. However, it is unclear which viral gene causes these effects. In this study, we investigated the effects of TGEV nucleocapsid (N) protein on PK-15 cells. We found that TGEV N protein suppressed cell proliferation by causing cell cycle arrest at the S and G2/M phases and apoptosis. Characterization of various cellular proteins that are involved in regulating cell cycle progression demonstrated that the expression of N gene resulted in an accumulation of p53 and p21, which suppressed cyclin B1, cdc2 and cdk2 expression. Moreover, the expression of TGEV N gene promoted translocation of Bax to mitochondria, which in turn caused the release of cytochrome c, followed by activation of caspase-3, resulting in cell apoptosis in the transfected PK-15 cells following cell cycle arrest. Further studies showed that p53 inhibitor attenuated TGEV N protein induced cell cycle arrest at S and G2/M phases and apoptosis through reversing the expression changes of cdc2, cdk2 and cyclin B1 and the translocation changes of Bax and cytochrome c induced by TGEV N protein. Taken together, these results demonstrated that TGEV N protein might play an important role in TGEV infection-induced p53 activation and cell cycle arrest at the S and G2/M phases and apoptosis occurrence.

  6. Autophagy induction promotes aristolochic acid-I-induced renal injury in vivo and in vitro

    Graphical abstract: - Highlights: • Aristolochic acid induced autophagy in vivo and in vitro. • Autophagy induced by aristolochic acid could promote cell apoptosis. • Inhibition autophagy by silencing ATG5 could prevent cell from programmed cell death induced by aristolochic acid. - Abstract: Studies have found that ingestion of aristolochic acid (AA) causes nephropathy first by inducing renal tubular cell apoptosis acutely. It is currently unknown whether crosstalk between autophagy and apoptosis orchestrates the fate of tubular cells in acute AA nephropathy. We tested this hypothesis by acute administration of AA in vivo and in vitro. Autophagy was first induced in vivo through enhancing Atg5 and LC3-II expressions in kidneys of AA-I-treated rats. Punctuate LC3-GFP dots and autophagosomes were detected in this acute AA-I nephropathy rat model. We subsequently utilized normal rat renal proximal tubular epithelial cells (NRK52E) to study the autophagy mechanisms involved in acute AA-I nephropathy, with 100 μM AA-I (median lethal dose 50) given in vitro. Cleavage of poly (ADP-ribose) polymerase (PARP), nuclear condensation, and fragmentation were demonstrated in the AA-I-treated NRK52E cells. Furthermore, AA-I induced Atg5 and LC3-II expressions and punctuated LC3-GFP dots. Autophagy flux by using lysosome inhibitor E64 induced the accumulation of LC3-II, which further promoted apoptosis through enhancing PARP cleavage. Inhibition of autophagy by 3-methyl adenine also led to the attenuation of AA-I-induced apoptosis, manifesting as decreased PARP cleavage, nuclei condensation, and decreased the number of cells negative for acridine orange/ethidium bromide staining. In addition, knockdown of Atg5 by short hairpin RNA attenuated LC3-II expression and PARP cleavage in NRK52E cells. Taken together, these findings suggested that the acute phase of AA-I-induced nephropathy is associated with induction of Atg5-dependent autophagy, which promotes renal tubular cell

  7. Induction of apoptosis by the retinoid inducible growth regulator RIG1 depends on the NC motif in HtTA cervical cancer cells

    Lin Su-Ching

    2009-02-01

    Full Text Available Abstract Background Retinoid-inducible gene 1 (RIG1, also known as tazarotene-induced gene 3 or retinoic-acid receptor responder 3, is a growth regulator, which induces apoptosis and differentiation. RIG1 is classified into the NC protein family. This study investigated functional domains and critical amino acids associated with RIG1-mediated cell death and apoptosis. Results Using enhanced green fluorescence protein (EGFP-tagged RIG1 variants, RIG1 proteins with deletion at the NC domain significantly decreased cell death induced by RIG1, and fusion variants containing only the NC domain significantly induced apoptosis of HtTA cervical cancer cells. The EGFP-RIG1-induced apoptosis was significantly decreased in cells expressing N112C113 motif double- (NC→FG or triple- (NCR→FGE mutated RIG1 variants. Using dodecapeptides, nuclear localization and profound cell death was observed in HtTA cells expressing wild type RIG1111–123 or Leu121-mutated RIG1111–123:L→ C peptide, but peptides double- or triple-mutated at the NC motif alone, RIG1111–123:NC→FG or RIG1111–123:NCR→FGE, were cytoplasmically localized and did not induce apoptosis. The RIG1111–123 also induced apoptosis of A2058 melanoma cells but not normal human fibroblasts. Conclusion The NC domain, especially the NC motif, plays the major role in RIG1-mediated pro-apoptotic activity. The RIG1111–123 dodecapeptide exhibited strong pro-apoptotic activity and has potential as an anticancer drug.

  8. The role of apoptosis in MCLR-induced developmental toxicity in zebrafish embryos

    Zeng, Cheng [College of Fisheries, Huazhong Agricultural University, Wuhan 430070 (China); Sun, Hong [Hubei Maternal and Child Health Hospital, Wuhan 430070 (China); Xie, Ping [Donghu Experimental Station of Lake Ecosystems, State Key Laboratory for Freshwater Ecology and Biotechnology of China, Institute of Hydrobiology, The Chinese Academy of Sciences, Wuhan 430072 (China); Wang, Jianghua; Zhang, Guirong; Chen, Nan [College of Fisheries, Huazhong Agricultural University, Wuhan 430070 (China); Yan, Wei, E-mail: Yanwei75126@163.com [Institute of Agricultural Quality Standards and Testing Technology, Hubei Academy of Agricultural Sciences, Wuhan 430064 (China); Li, Guangyu, E-mail: ligy2001@163.com [College of Fisheries, Huazhong Agricultural University, Wuhan 430070 (China); Freshwater Aquaculture Collaborative Innovation Center of Hubei Province, Wuhan 430070 (China)

    2014-04-01

    Highlights: • MCLR-induced apoptosis in the heart of developing embryos leads to the growth delay in zebrafish. • MCLR-triggered apoptosis might be induced by ROS. • P53–Bax–Bcl-2 and caspase-dependent apoptotic pathway contribute greatly to MCLR-induced apoptosis. Abstract: We previously demonstrated that cyanobacteria-derived microcystin–leucine–arginine (MCLR) is able to induce developing toxicity, such as malformation, growth delay and also decreased heart rates in zebrafish embryos. However, the molecular mechanisms by which MCLR induces its toxicity during the development of zebrafish remain largely unknown. Here, we evaluate the role of apoptosis in MCLR-induced developmental toxicity. Zebrafish embryos were exposed to various concentrations of MCLR (0, 0.2, 0.5, 2, and 5.0 mg L⁻¹ for 96 h, at which time reactive oxygen species (ROS) was significantly induced in the 2 and 5.0 mg L⁻¹ MCLR exposure groups. Acridine orange (AO) staining and terminal deoxynucleotide transferase-mediated deoxy-UTP nick end labelling (TUNEL) assay showed that MCLR exposure resulted in cell apoptosis. To test the apoptotic pathway, the expression pattern of several apoptotic-related genes was examined for the level of enzyme activity, gene and protein expression, respectively. The overall results demonstrate that MCLR induced ROS which consequently triggered apoptosis in the heart of developing zebrafish embryos. Our results also indicate that the p53–Bax–Bcl-2 pathway and the caspase-dependent apoptotic pathway play major roles in MCLR-induced apoptosis in the developing embryos.

  9. The role of apoptosis in MCLR-induced developmental toxicity in zebrafish embryos

    Highlights: • MCLR-induced apoptosis in the heart of developing embryos leads to the growth delay in zebrafish. • MCLR-triggered apoptosis might be induced by ROS. • P53–Bax–Bcl-2 and caspase-dependent apoptotic pathway contribute greatly to MCLR-induced apoptosis. - Abstract: We previously demonstrated that cyanobacteria-derived microcystin–leucine–arginine (MCLR) is able to induce developing toxicity, such as malformation, growth delay and also decreased heart rates in zebrafish embryos. However, the molecular mechanisms by which MCLR induces its toxicity during the development of zebrafish remain largely unknown. Here, we evaluate the role of apoptosis in MCLR-induced developmental toxicity. Zebrafish embryos were exposed to various concentrations of MCLR (0, 0.2, 0.5, 2, and 5.0 mg L−1) for 96 h, at which time reactive oxygen species (ROS) was significantly induced in the 2 and 5.0 mg L−1 MCLR exposure groups. Acridine orange (AO) staining and terminal deoxynucleotide transferase-mediated deoxy-UTP nick end labelling (TUNEL) assay showed that MCLR exposure resulted in cell apoptosis. To test the apoptotic pathway, the expression pattern of several apoptotic-related genes was examined for the level of enzyme activity, gene and protein expression, respectively. The overall results demonstrate that MCLR induced ROS which consequently triggered apoptosis in the heart of developing zebrafish embryos. Our results also indicate that the p53–Bax–Bcl-2 pathway and the caspase-dependent apoptotic pathway play major roles in MCLR-induced apoptosis in the developing embryos

  10. Hormesis in Cholestatic Liver Disease; Preconditioning with Low Bile Acid Concentrations Protects against Bile Acid-Induced Toxicity.

    Esther M Verhaag

    Full Text Available Cholestasis is characterized by accumulation of bile acids and inflammation, causing hepatocellular damage. Still, liver damage markers are highest in acute cholestasis and drop when this condition becomes chronic, indicating that hepatocytes adapt towards the hostile environment. This may be explained by a hormetic response in hepatocytes that limits cell death during cholestasis.To investigate the mechanisms that underlie the hormetic response that protect hepatocytes against experimental cholestatic conditions.HepG2.rNtcp cells were preconditioned (24 h with sub-apoptotic concentrations (0.1-50 μM of various bile acids, the superoxide donor menadione, TNF-α or the Farsenoid X Receptor agonist GW4064, followed by a challenge with the apoptosis-inducing bile acid glycochenodeoxycholic acid (GCDCA; 200 μM for 4 h, menadione (50 μM, 6 h or cytokine mixture (CM; 6 h. Levels of apoptotic and necrotic cell death, mRNA expression of the bile salt export pump (ABCB11 and bile acid sensors, as well as intracellular GCDCA levels were analyzed.Preconditioning with the pro-apoptotic bile acids GCDCA, taurocholic acid, or the protective bile acids (tauroursodeoxycholic acid reduced GCDCA-induced caspase-3/7 activity in HepG2.rNtcp cells. Bile acid preconditioning did not induce significant levels of necrosis in GCDCA-challenged HepG2.rNtcp cells. In contrast, preconditioning with cholic acid, menadione or TNF-α potentiated GCDCA-induced apoptosis. GCDCA preconditioning specifically reduced GCDCA-induced cell death and not CM- or menadione-induced apoptosis. The hormetic effect of GCDCA preconditioning was concentration- and time-dependent. GCDCA-, CDCA- and GW4064- preconditioning enhanced ABCB11 mRNA levels, but in contrast to the bile acids, GW4064 did not significantly reduce GCDCA-induced caspase-3/7 activity. The GCDCA challenge strongly increased intracellular levels of this bile acid, which was not lowered by GCDCA

  11. Hormesis in Cholestatic Liver Disease; Preconditioning with Low Bile Acid Concentrations Protects against Bile Acid-Induced Toxicity

    Verhaag, Esther M.; Buist-Homan, Manon; Koehorst, Martijn; Groen, Albert K.; Moshage, Han; Faber, Klaas Nico

    2016-01-01

    Introduction Cholestasis is characterized by accumulation of bile acids and inflammation, causing hepatocellular damage. Still, liver damage markers are highest in acute cholestasis and drop when this condition becomes chronic, indicating that hepatocytes adapt towards the hostile environment. This may be explained by a hormetic response in hepatocytes that limits cell death during cholestasis. Aim To investigate the mechanisms that underlie the hormetic response that protect hepatocytes against experimental cholestatic conditions. Methods HepG2.rNtcp cells were preconditioned (24 h) with sub-apoptotic concentrations (0.1–50 μM) of various bile acids, the superoxide donor menadione, TNF-α or the Farsenoid X Receptor agonist GW4064, followed by a challenge with the apoptosis-inducing bile acid glycochenodeoxycholic acid (GCDCA; 200 μM for 4 h), menadione (50 μM, 6 h) or cytokine mixture (CM; 6 h). Levels of apoptotic and necrotic cell death, mRNA expression of the bile salt export pump (ABCB11) and bile acid sensors, as well as intracellular GCDCA levels were analyzed. Results Preconditioning with the pro-apoptotic bile acids GCDCA, taurocholic acid, or the protective bile acids (tauro)ursodeoxycholic acid reduced GCDCA-induced caspase-3/7 activity in HepG2.rNtcp cells. Bile acid preconditioning did not induce significant levels of necrosis in GCDCA-challenged HepG2.rNtcp cells. In contrast, preconditioning with cholic acid, menadione or TNF-α potentiated GCDCA-induced apoptosis. GCDCA preconditioning specifically reduced GCDCA-induced cell death and not CM- or menadione-induced apoptosis. The hormetic effect of GCDCA preconditioning was concentration- and time-dependent. GCDCA-, CDCA- and GW4064- preconditioning enhanced ABCB11 mRNA levels, but in contrast to the bile acids, GW4064 did not significantly reduce GCDCA-induced caspase-3/7 activity. The GCDCA challenge strongly increased intracellular levels of this bile acid, which was not lowered by GCDCA

  12. Bisdemethoxycurcumin Induces Apoptosis in Activated Hepatic Stellate Cells via Cannabinoid Receptor 2

    Phil Jun Lee

    2015-01-01

    Full Text Available Activated Hepatic Stellate Cells (HSCs, major fibrogenic cells in the liver, undergo apoptosis when liver injuries cease, which may contribute to the resolution of fibrosis. Bisdemethoxycurcumin (BDMC is a natural derivative of curcumin with anti-inflammatory and anti-cancer activities. The therapeutic potential of BDMC in hepatic fibrosis has not been studied thus far in the context of the apoptosis in activated HSCs. In the current study, we compared the activities of BDMC and curcumin in the HSC-T6 cell line and demonstrated that BDMC relatively induced a potent apoptosis. BDMC-induced apoptosis was mediated by a combinatory inhibition of cytoprotective proteins, such as Bcl2 and heme oxygenase-1 and increased generation of reactive oxygen species. Intriguingly, BDMC-induced apoptosis was reversed with co-treatment of sr144528, a cannabinoid receptor (CBR 2 antagonist, which was confirmed with genetic downregulation of the receptor using siCBR2. Additionally, incubation with BDMC increased the formation of death-induced signaling complex in HSC-T6 cells. Treatment with BDMC significantly diminished total intracellular ATP levels and upregulated ATP inhibitory factor-1. Collectively, the results demonstrate that BDMC induces apoptosis in activated HSCs, but not in hepatocytes, by impairing cellular energetics and causing a downregulation of cytoprotective proteins, likely through a mechanism that involves CBR2.

  13. MicroRNA-208a Silencing Attenuates Doxorubicin Induced Myocyte Apoptosis and Cardiac Dysfunction

    Hasahya Tony

    2015-01-01

    Full Text Available Aims. GATA4 depletion is a distinct mechanism by which doxorubicin leads to cardiomyocyte apoptosis, and preservation of GATA4 mitigates doxorubicin induced myocyte apoptosis and cardiac dysfunction. We investigated a novel approach of attenuating doxorubicin induced cardiac toxicity by silencing miR-208a, a heart specific microRNA known to target GATA4. Methods and Results. Eight-week-old female Balb/C mice were randomly assigned to sham, antagomir, and control groups. Antagomir group were pretreated with miR-208a antagomir 4 days before doxorubicin administration. At day 0, control and antagomir groups received 20 mg/kg of doxorubicin, while sham mice received phosphate buffered solution. Echocardiography was done at day 7, after which animals were sacrificed and hearts harvested and assessed for apoptosis and expression of miR-208a, GATA4, and BCL-2. Doxorubicin significantly upregulated miR-208a, downregulated GATA4, and increased myocyte apoptosis, with resulting decrease in cardiac function. In contrast, therapeutic silencing of miR-208a salvaged GATA4 and BCL-2 and decreased apoptosis, with improvement in cardiac function. Conclusion. Doxorubicin upregulates miR-208a and promotes cardiomyocyte apoptosis, while therapeutic silencing of miR-208a attenuates doxorubicin induced myocyte apoptosis with subsequent improvement in cardiac function. These novel results highlight the therapeutic potential of targeting miR-208a to prevent doxorubicin cardiotoxicity.

  14. Siderocalin/Lcn2/NGAL/24p3 does not drive apoptosis through gentisic acid mediated iron withdrawal in hematopoietic cell lines.

    Colin Correnti

    Full Text Available Siderocalin (also lipocalin 2, NGAL or 24p3 binds iron as complexes with specific siderophores, which are low molecular weight, ferric ion-specific chelators. In innate immunity, siderocalin slows the growth of infecting bacteria by sequestering bacterial ferric siderophores. Siderocalin also binds simple catechols, which can serve as siderophores in the damaged urinary tract. Siderocalin has also been proposed to alter cellular iron trafficking, for instance, driving apoptosis through iron efflux via BOCT. An endogenous siderophore composed of gentisic acid (2,5-dihydroxybenzoic acid substituents was proposed to mediate cellular efflux. However, binding studies reported herein contradict the proposal that gentisic acid forms high-affinity ternary complexes with siderocalin and iron, or that gentisic acid can serve as an endogenous siderophore at neutral pH. We also demonstrate that siderocalin does not induce cellular iron efflux or stimulate apoptosis, questioning the role siderocalin plays in modulating iron metabolism.

  15. Experimental effect of retinoic acids on apoptosis during the development of diabetic retinopathy

    Nami Nishikiori; Makoto Osanai; Hideki Chiba; Takashi Kojima; Shuichiro Inatomi; et al.

    2008-01-01

    Nami Nishikiori1,2, Makoto Osanai2, Hideki Chiba2, Takashi Kojima2, Shuichiro Inatomi1,2, Hiroshi Ohguro1, Norimasa Sawada2Departments of 1Ophthalmology and 2Pathology, Sapporo Medical University School of MedicinePurpose: This study was conducted to investigate whether retinoic acids (RAs) had any effect on apoptosis during the development of diabetic retinopathy.Methods: To investigate whether RAs had any effect on apoptosis during the development of diabetic retinopathy, we housed 32 C57BL...

  16. Autophagy protects monocytes from Wolbachia heat shock protein 60-induced apoptosis and senescence.

    Vijayan Kamalakannan

    2015-04-01

    Full Text Available Monocyte dysfunction by filarial antigens has been a major mechanism underlying immune evasion following hyporesponsiveness during patent lymphatic filariasis. Recent studies have initiated a paradigm shift to comprehend the immunological interactions of Wolbachia and its antigens in inflammation, apoptosis, lymphocyte anergy, etc. Here we showed that recombinant Wolbachia heat shock protein 60 (rWmhsp60 interacts with TLR-4 and induces apoptosis in monocytes of endemic normal but not in chronic patients. Higher levels of reactive oxygen species (ROS induced after TLR-4 stimulation resulted in loss of mitochondrial membrane potential and caspase cascade activation, which are the plausible reason for apoptosis. Furthermore, release in ROS owing to TLR-4 signaling resulted in the activation of NF-κB p65 nuclear translocation which leads to inflammation and apoptosis via TNF receptor pathway following the increase in IL-6 and TNF-α level. Here for the first time, we report that in addition to apoptosis, rWmhsp60 antigen in filarial pathogenesis also induces molecular senescence in monocytes. Targeting TLR-4, therefore, presents a promising candidate for treating rWmhsp60-induced apoptosis and senescence. Strikingly, induction of autophagy by rapamycin detains TLR-4 in late endosomes and subverts TLR-4-rWmhsp60 interaction, thus protecting TLR-4-mediated apoptosis and senescence. Furthermore, rapamycin-induced monocytes were unresponsive to rWmhsp60, and activated lymphocytes following PHA stimulation. This study demonstrates that autophagy mediates the degradation of TLR-4 signaling and protects monocytes from rWmhsp60 induced apoptosis and senescence.

  17. Autophagy protects monocytes from Wolbachia heat shock protein 60-induced apoptosis and senescence.

    Kamalakannan, Vijayan; Shiny, Abijit; Babu, Subash; Narayanan, Rangarajan Badri

    2015-04-01

    Monocyte dysfunction by filarial antigens has been a major mechanism underlying immune evasion following hyporesponsiveness during patent lymphatic filariasis. Recent studies have initiated a paradigm shift to comprehend the immunological interactions of Wolbachia and its antigens in inflammation, apoptosis, lymphocyte anergy, etc. Here we showed that recombinant Wolbachia heat shock protein 60 (rWmhsp60) interacts with TLR-4 and induces apoptosis in monocytes of endemic normal but not in chronic patients. Higher levels of reactive oxygen species (ROS) induced after TLR-4 stimulation resulted in loss of mitochondrial membrane potential and caspase cascade activation, which are the plausible reason for apoptosis. Furthermore, release in ROS owing to TLR-4 signaling resulted in the activation of NF-κB p65 nuclear translocation which leads to inflammation and apoptosis via TNF receptor pathway following the increase in IL-6 and TNF-α level. Here for the first time, we report that in addition to apoptosis, rWmhsp60 antigen in filarial pathogenesis also induces molecular senescence in monocytes. Targeting TLR-4, therefore, presents a promising candidate for treating rWmhsp60-induced apoptosis and senescence. Strikingly, induction of autophagy by rapamycin detains TLR-4 in late endosomes and subverts TLR-4-rWmhsp60 interaction, thus protecting TLR-4-mediated apoptosis and senescence. Furthermore, rapamycin-induced monocytes were unresponsive to rWmhsp60, and activated lymphocytes following PHA stimulation. This study demonstrates that autophagy mediates the degradation of TLR-4 signaling and protects monocytes from rWmhsp60 induced apoptosis and senescence. PMID:25849993

  18. Calcium-Mediated Mitochondrial Permeability Transition Involved in Hydrogen Peroxide-Induced Apoptosis in Tobacco Protoplasts

    2006-01-01

    In the present study, we focused on whether intracellular free Ca2+ ([Ca2+]i) regulates the formation of mitochondrial permeability transition pore (MPTP) in H2O2-induced apoptosis in tobacco protoplasts. It was shown that the decrease in mitochondrial membrane potential (△Ψm) preceded the appearance of H2O2-induced apoptosis;pretreatment with the specific MPTP inhibitor cyclosporine A, which also inhibits Ca2+ cycling by the mitochondria,effectively retarded apoptosis and the decrease in △Ψm. Apoptosis and decreased △Ψm were exacerbated by CaCl2, whereas the plasma membrane voltage-dependent Ca2+ channel blocker lanthanum chloride (LaCl3)attentuated these responses. Chelation of extracellular Ca2+ with EGTA almost totally inhibited apoptosis and the decrease in △Ψm induced by H2O2. The time-course of changes in [Ca2+]i in apoptosis was detected using the Ca2+ probe Fluo-3 AM. These studies showed that [Ca2+]i was increased at the very early stage of H2O2-induced apoptosis. The EGTA evidently inhibited the increase in [Ca2+]i induced by H2O2, whereas it was only partially inhibited by LaCl3. The results suggest that H2O2 may elevate cytoplasmic free Ca2+ concentrations in tobacco protoplasts, which mainly results from the entry of extracellular Ca2+, to regulate mitochondrial permeability transition. The signaling pathway of [Ca2+]i-mediated mitochondrial permeability transition was associated with H2O2-induced apoptosis in tobacco protoplasts.

  19. N-acetyl-L-cysteine inhibits bleomycin induced apoptosis in malignant testicular germ cell tumors.

    Kucuksayan, Ertan; Cort, Aysegul; Timur, Mujgan; Ozdemir, Evrim; Yucel, Suleyman Gultekin; Ozben, Tomris

    2013-07-01

    Antioxidants may prevent apoptosis of cancer cells via inhibiting reactive oxygen species (ROS). However, to date no study has been carried out to elucidate the effects of strong antioxidant N-acetylcysteine (NAC) on Bleomycin induced apoptosis in human testicular cancer (NTERA-2, NT2) cells. For this reason, we studied the effects of Bleomycin and NAC alone and in combination on apoptotic signaling pathways in NT2 cell line. We determined the cytotoxic effect of bleomycin on NT2 cells and measured apoptosis markers such as Caspase-3, -8, -9 activities and Bcl-2, Bax, Cyt-c, Annexin V-FTIC and PI levels in NT2 cells incubated with different agents for 24 h. Early apoptosis was determined using FACS assay. We found half of the lethal dose (LD50) of Bleomycin on NT2 cell viability as 400, 100, and 20 µg/ml after incubations for 24, 48, and 72 h, respectively. Incubation with bleomycin (LD50 ) and H2O2 for 24 h increased Caspase-3, -8, -9 activities, Cyt-c and Bax levels and decreased Bcl-2 levels. The concurrent incubation of NT2 cells with bleomycin/H2O2 and NAC (5 mM) for 24 h abolished bleomycin/H2O2-dependent increases in Caspase-3, -8, -9 activities, Bax and Cyt-c levels and bleomycin/H2O2-dependent decrease in Bcl-2 level. Our results indicate that bleomycin/H2O2 induce apoptosis in NT2 cells by activating mitochondrial pathway of apoptosis, while NAC diminishes bleomycin/H2O2 induced apoptosis. We conclude that NAC has antagonistic effects on Bleomycin-induced apoptosis in NT2 cells and causes resistance to apoptosis which is not a desired effect in eliminating cancer cells. PMID:23386420

  20. Parkia javanica Extract Induces Apoptosis in S-180 Cells via the Intrinsic Pathway of Apoptosis.

    Patra, Kartick; Jana, Samarjit; Sarkar, Arnab; Karmakar, Subrata; Jana, Jagannath; Gupta, Mradu; Mukherjee, Gopeswar; De, Utpal Chandra; Mandal, Deba Prasad; Bhattacharjee, Shamee

    2016-01-01

    Parkia javanica is a leguminous tree, various parts of which are used as food and folklore medicine by the ethnic groups of northeastern India. The present study investigates the in vitro and in vivo anticancer effect of aqueous methanol extract of P. javanica fruit (PJE). HPLC analysis was done to establish the fingerprint chromatogram of PJE and its in vitro radical scavenging activity was measured. PJE caused significant cytotoxicity in sarcoma-180 (S-180), A549, AGS, and MDA-MB435S cancer cells in vitro. Exploration of the mechanistic details in S-180 cells suggested that the reduced cell viability was mediated by induction of apoptosis. Increased expression of proapoptotic proteins such as p53, p21, Bax/Bcl2, cytochrome c (Cyt c), caspase 9, and cleaved poly(ADP-ribose) polymerase, and decrease in proliferative and antiapoptotic markers (Ki-67, Proliferating Cell Nuclear Antigen [PCNA], Bcl-2) validated the anticancer effect of PJE. A decline in the relative fluorescence emission upon staining S-180 cells with Rhodamine 123 (Rh 123), enhanced expression of cytosolic Cyt c and mitochondrial Bax, and inhibition of apoptosis in the presence of caspase-9 inhibitor in PJE-treated cells indicated intrinsic pathway of apoptosis. Liver function test and hepatic antioxidant enzymes demonstrated non-toxicity of PJE. Finally, the detection of PJE in sera by HPLC confirmed its bioavailability. PMID:27144503

  1. Roscovitine sensitizes breast cancer cells to TRAIL-induced apoptosis through a pleiotropic mechanism

    Gustavo Ortiz-Ferrón; Rosario Yerbes; Adriana Eramo; Ana I López-Pérez; Ruggero De Maria; Abelardo López-Rivas

    2008-01-01

    The tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL/APO2L) is a member of the TNF gene superfamily that induces apoptosis upon engagement of cognate death receptors.While TRAIL is relatively non-toxic to normal cells,it selectively induces apoptosis in many transformed cells.Nevertheless,breast tumor cells are particularly resistant to the effects of TRAIL.Here we report that,in combination with the cyclin-dependent kinase inhibitor roscovitine,exposure to TRAIL induced marked apoptosis in the majority of TRAIL-resistant breast cancer cell Iines examined.Roscovitine facilitated TRAIL death-inducing signaling complex formation and the activation of caspase-8.The cFLIPL and eFLIPs FLICE-inhibitory proteins were significantly down-regulated following exposure to roscovitine and,indeed,the knockdown of cFLIP isoforms by siRNA sensitized breast tumor cells to TRAIL-induced apoptosis.In addition,we demonstrate that roscovitine strongly suppressed Mcl-1 expression and up-regulated E2F1 protein levels in breast tumor cells.Significantly,the silencing of Mcl-1 by siRNA sensitized breast tumor cells to TRAIL-induced apoptosis.Furthermore,the knockdown of E2F1 protein by siRNA reduced the sensitizing effect of roscovitine in TRAIL-induced apoptosis.In summary,our results reveal a pleitropic mechanism for the pro-apoptotic influence of roscovitine,highlighting its potential as an antitumor agent in breast cancer in combination with TRAIL.

  2. p53 modulates the AMPK inhibitor compound C induced apoptosis in human skin cancer cells

    Huang, Shi-Wei [Institute of Biomedical Sciences, National Chung Hsing University, Taichung, Taiwan (China); Wu, Chun-Ying [Division of Gastroenterology and Hepatology, Taichung Veterans General Hospital, Taichung, Taiwan (China); Wang, Yen-Ting [Department of Medical Research and Education, Cheng Hsin General Hospital, Taipei, Taiwan (China); Kao, Jun-Kai [Institute of Biomedical Sciences, National Chung Hsing University, Taichung, Taiwan (China); Department of Pediatrics, Children' s Hospital, Changhua Christian Hospital, Changhua, Taiwan (China); Lin, Chi-Chen; Chang, Chia-Che; Mu, Szu-Wei; Chen, Yu-Yu [Institute of Biomedical Sciences, National Chung Hsing University, Taichung, Taiwan (China); Chiu, Husan-Wen [Institute of Biotechnology, National Cheng-Kung University, Tainan, Taiwan (China); Agricultural Biotechnology Research Center, Academia Sinica, Taipei, Taiwan (China); Chang, Chuan-Hsun [Department of Surgical Oncology, Cheng Hsin General Hospital, Taipei, Taiwan (China); Department of Nutrition Therapy, Cheng Hsin General Hospital, Taipei, Taiwan (China); School of Nutrition and Health Sciences, Taipei Medical University, Taipei, Taiwan (China); Liang, Shu-Mei [Institute of Biotechnology, National Cheng-Kung University, Tainan, Taiwan (China); Agricultural Biotechnology Research Center, Academia Sinica, Taipei, Taiwan (China); Chen, Yi-Ju [Department of Dermatology, Taichung Veterans General Hospital, Taichung, Taiwan (China); Huang, Jau-Ling [Department of Bioscience Technology, Chang Jung Christian University, Tainan, Taiwan (China); Shieh, Jeng-Jer, E-mail: shiehjj@vghtc.gov.tw [Institute of Biomedical Sciences, National Chung Hsing University, Taichung, Taiwan (China); Department of Education and Research, Taichung Veterans General Hospital, Taichung, Taiwan (China)

    2013-02-15

    Compound C, a well-known inhibitor of the intracellular energy sensor AMP-activated protein kinase (AMPK), has been reported to cause apoptotic cell death in myeloma, breast cancer cells and glioma cells. In this study, we have demonstrated that compound C not only induced autophagy in all tested skin cancer cell lines but also caused more apoptosis in p53 wildtype skin cancer cells than in p53-mutant skin cancer cells. Compound C can induce upregulation, phosphorylation and nuclear translocalization of the p53 protein and upregulate expression of p53 target genes in wildtype p53-expressing skin basal cell carcinoma (BCC) cells. The changes of p53 status were dependent on DNA damage which was caused by compound C induced reactive oxygen species (ROS) generation and associated with activated ataxia-telangiectasia mutated (ATM) protein. Using the wildtype p53-expressing BCC cells versus stable p53-knockdown BCC sublines, we present evidence that p53-knockdown cancer cells were much less sensitive to compound C treatment with significant G2/M cell cycle arrest and attenuated the compound C-induced apoptosis but not autophagy. The compound C induced G2/M arrest in p53-knockdown BCC cells was associated with the sustained inactive Tyr15 phosphor-Cdc2 expression. Overall, our results established that compound C-induced apoptosis in skin cancer cells was dependent on the cell's p53 status. - Highlights: ► Compound C caused more apoptosis in p53 wildtype than p53-mutant skin cancer cells. ► Compound C can upregulate p53 expression and induce p53 activation. ► Compound C induced p53 effects were dependent on ROS induced DNA damage pathway. ► p53-knockdown attenuated compound C-induced apoptosis but not autophagy. ► Compound C-induced apoptosis in skin cancer cells was dependent on p53 status.

  3. p53 modulates the AMPK inhibitor compound C induced apoptosis in human skin cancer cells

    Compound C, a well-known inhibitor of the intracellular energy sensor AMP-activated protein kinase (AMPK), has been reported to cause apoptotic cell death in myeloma, breast cancer cells and glioma cells. In this study, we have demonstrated that compound C not only induced autophagy in all tested skin cancer cell lines but also caused more apoptosis in p53 wildtype skin cancer cells than in p53-mutant skin cancer cells. Compound C can induce upregulation, phosphorylation and nuclear translocalization of the p53 protein and upregulate expression of p53 target genes in wildtype p53-expressing skin basal cell carcinoma (BCC) cells. The changes of p53 status were dependent on DNA damage which was caused by compound C induced reactive oxygen species (ROS) generation and associated with activated ataxia-telangiectasia mutated (ATM) protein. Using the wildtype p53-expressing BCC cells versus stable p53-knockdown BCC sublines, we present evidence that p53-knockdown cancer cells were much less sensitive to compound C treatment with significant G2/M cell cycle arrest and attenuated the compound C-induced apoptosis but not autophagy. The compound C induced G2/M arrest in p53-knockdown BCC cells was associated with the sustained inactive Tyr15 phosphor-Cdc2 expression. Overall, our results established that compound C-induced apoptosis in skin cancer cells was dependent on the cell's p53 status. - Highlights: ► Compound C caused more apoptosis in p53 wildtype than p53-mutant skin cancer cells. ► Compound C can upregulate p53 expression and induce p53 activation. ► Compound C induced p53 effects were dependent on ROS induced DNA damage pathway. ► p53-knockdown attenuated compound C-induced apoptosis but not autophagy. ► Compound C-induced apoptosis in skin cancer cells was dependent on p53 status

  4. Involvement of seven in absentia homolog-1 in ethanol-induced apoptosis in neural crest cells

    Sun, Haijing; Chen, Xiaopan; Yuan, Fuqiang; Liu, Jie; Zhao, Yingming; Chen, Shao-yu

    2014-01-01

    Ethanol-induced apoptosis in selected cell populations is a major component of pathogenesis underlying ethanol-induced teratogenesis. However, there is a fundamental gap in understanding how ethanol leads to apoptosis in embryos. In this study, we investigate the role of seven in absentia homolog-1 (Siah1) protein, an E3 ubiquitin ligase, in ethanol-induced apoptosis. Using an in vitro model of neural crest cell (NCC), JoMa1.3 cells, we found that exposure to 100 mM ethanol resulted in a significant increase in Siah1 mRNA expression in NCCs, an ethanol-sensitive cell population implicated in Fetal Alcohol Spectrum Disorders (FASD). Treatment with 100 mM ethanol for 24 hours also significantly increased the protein expression of Siah1 in JoMa1.3 cells. The nuclear translocation and accumulation of Siah1 was evidenced in the cells exposed to ethanol. In addition, we have found that the inhibition of Siah1 function with siRNA prevents ethanol-induced increase in Siah1 protein expression and nuclear translocation in NCCs. Down-regulation of Siah1 by siRNA also greatly diminished ethanol-induced cell death and caspase-3 activation, indicating that inhibition of Siah1 can attenuate ethanol-induced apoptosis. These results strongly suggest that Siah1 plays an important role in ethanol-induced apoptosis in NCCs. PMID:25193017

  5. Wogonin Induces Reactive Oxygen Species Production and Cell Apoptosis in Human Glioma Cancer Cells

    Dah-Yuu Lu

    2012-08-01

    Full Text Available Glioma is the most common primary adult brain tumor with poor prognosis because of the ease of spreading tumor cells to other regions of the brain. Cell apoptosis is frequently targeted for developing anti-cancer drugs. In the present study, we have assessed wogonin, a flavonoid compound isolated from Scutellaria baicalensis Georgi, induced ROS generation, endoplasmic reticulum (ER stress and cell apoptosis. Wogonin induced cell death in two different human glioma cells, such as U251 and U87 cells but not in human primary astrocytes (IC 50 > 100 μM. Wogonin-induced apoptotic cell death in glioma cells was measured by propidine iodine (PI analysis, Tunnel assay and Annexin V staining methods. Furthermore, wogonin also induced caspase-9 and caspase-3 activation as well as up-regulation of cleaved PARP expression. Moreover, treatment of wogonin also increased a number of signature ER stress markers glucose-regulated protein (GRP-78, GRP-94, Calpain I, and phosphorylation of eukaryotic initiation factor-2α (eIF2α. Treatment of human glioma cells with wogonin was found to induce reactive oxygen species (ROS generation. Wogonin induced ER stress-related protein expression and cell apoptosis was reduced by the ROS inhibitors apocynin and NAC (N-acetylcysteine. The present study provides evidence to support the fact that wogonin induces human glioma cell apoptosis mediated ROS generation, ER stress activation and cell apoptosis.

  6. The mechanism mediating nuclear translocation of the apoptosis inducing factor (AIF)

    Cunha, Rita Isabel Costa

    2012-01-01

    Dissertação de mestrado em Genética Molecular Since the discovery that yeast cells can undergo programmed cell death in response to several different stimuli, Saccharomyces cerevisiae has gained prominence in the cell death field. Exposure of yeast cells to certain stimuli like acetic acid or hydrogen peroxide or even heterologous expression of pro-apoptotic proteins can trigger cell death by apoptosis via a mitochondrial pathway and exhibiting the typical hallmarks of apoptosi...

  7. A novel firefly luciferase biosensor enhances the detection of apoptosis induced by ESAT-6 family proteins of Mycobacterium tuberculosis

    Shi, Junwei; Zhang, Huan; Fang, Liurong; Xi, Yongqiang; Zhou, Yanrong; Luo, Rui; Wang, Dang, E-mail: wangdang511@126.com; Xiao, Shaobo; Chen, Huanchun

    2014-10-03

    Highlights: • We developed a novel firefly luciferase based biosensor to detect apoptosis. • The novel biosensor 233-DnaE-DEVDG was reliable, sensitive and convenient. • 233-DnaE-DEVDG faithfully indicated ESAT-6 family proteins of Mycobacterium tuberculosis induced apoptosis. • EsxA, esxT and esxL in ESAT-6 family proteins induced apoptosis. • Activation of nuclear factor-κB (NF-κB) participated in esxT-induced apoptosis. - Abstract: The activation of caspase-3 is a key surrogate marker for detecting apoptosis. To quantitate caspase-3 activity, we constructed a biosensor comprising a recombinant firefly luciferase containing a caspase-3 cleavage site. When apoptosis was induced, caspase-3 cleavage of the biosensor activated firefly luciferase by a factor greater than 25. The assay conveniently detected apoptosis in real time, indicating that it will facilitate drug discovery. We screened ESAT-6 family proteins of Mycobacterium tuberculosis and found that esxA, esxT and esxL induced apoptosis. Further, activation of nuclear factor-κB (NF-κB) and the NF-κB-regulated genes encoding tumor necrosis factor-α (TNF-α) and tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) participated in esxT-induced apoptosis. We conclude that this assay is useful for high-throughput screening to identify and characterize proteins and drugs that regulate apoptosis.

  8. A novel firefly luciferase biosensor enhances the detection of apoptosis induced by ESAT-6 family proteins of Mycobacterium tuberculosis

    Highlights: • We developed a novel firefly luciferase based biosensor to detect apoptosis. • The novel biosensor 233-DnaE-DEVDG was reliable, sensitive and convenient. • 233-DnaE-DEVDG faithfully indicated ESAT-6 family proteins of Mycobacterium tuberculosis induced apoptosis. • EsxA, esxT and esxL in ESAT-6 family proteins induced apoptosis. • Activation of nuclear factor-κB (NF-κB) participated in esxT-induced apoptosis. - Abstract: The activation of caspase-3 is a key surrogate marker for detecting apoptosis. To quantitate caspase-3 activity, we constructed a biosensor comprising a recombinant firefly luciferase containing a caspase-3 cleavage site. When apoptosis was induced, caspase-3 cleavage of the biosensor activated firefly luciferase by a factor greater than 25. The assay conveniently detected apoptosis in real time, indicating that it will facilitate drug discovery. We screened ESAT-6 family proteins of Mycobacterium tuberculosis and found that esxA, esxT and esxL induced apoptosis. Further, activation of nuclear factor-κB (NF-κB) and the NF-κB-regulated genes encoding tumor necrosis factor-α (TNF-α) and tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) participated in esxT-induced apoptosis. We conclude that this assay is useful for high-throughput screening to identify and characterize proteins and drugs that regulate apoptosis

  9. Bozepinib, a novel small antitumor agent, induces PKR-mediated apoptosis and synergizes with IFNα triggering apoptosis, autophagy and senescence

    Marchal, Juan Antonio; Carrasco, Esther; Ramirez, Alberto; Jiménez, Gema; Olmedo, Carmen; Peran, Macarena; Agil, Ahmad; Conejo-García, Ana; Cruz-López, Olga; Campos, Joaquin María; García, María Ángel

    2013-01-01

    Bozepinib [(RS)-2,6-dichloro-9-[1-(p-nitrobenzenesulfonyl)-1,2,3,5-tetrahydro-4,1-benzoxazepin-3-yl]-9H-purine] is a potent antitumor compound that is able to induce apoptosis in breast cancer cells. In the present study, we show that bozepinib also has antitumor activity in colon cancer cells, showing 50% inhibitory concentration (IC50) values lower than those described for breast cancer cells and suggesting great potential of this synthetic drug in the treatment of cancer. We identified that the double-stranded RNA-dependent protein kinase (PKR) is a target of bozepinib, being upregulated and activated by the drug. However, p53 was not affected by bozepinib, and was not necessary for induction of apoptosis in either breast or colon cancer cells. In addition, the efficacy of bozepinib was improved when combined with the interferon-alpha (IFNα) cytokine, which enhanced bozepinib-induced apoptosis with involvement of protein kinase PKR. Moreover, we report here, for the first time, that in combined therapy, IFNα induces a clear process of autophagosome formation, and prior treatment with chloroquine, an autophagy inhibitor, is able to significantly reduce IFNα/bozepinib-induced cell death. Finally, we observed that a minor population of caspase 3-deficient MCF-7 cells persisted during long-term treatment with lower doses of bozepinib and the bozepinib/IFNα combination. Curiously, this population showed β-galactosidase activity and a percentage of cells arrested in S phase, that was more evident in cells treated with the bozepinib/IFNα combination than in cells treated with bozepinib or IFNα alone. Considering the resistance of some cancer cells to conventional chemotherapy, combinations enhancing the diversity of the cell death outcome might succeed in delivering more effective and less toxic chemotherapy. PMID:24194639

  10. Mitochondrial apoptosis of lymphocyte is induced in type 2 diabetes

    Xu Hui; Chen Yanbo; Li Yanxiang; Xia Fangzhen; Han Bing; Zhang Huixin; Zhai Hualing

    2014-01-01

    Background Lymphocyte function and homeostasis is associated with immune defence to infection.Apoptosis of lymphocytes might be a considerably important component which has an impact on immunity to infections in people with hyperglycemia.The aim of this study was to explore the mitochondrial apoptosis pathway of lymphocyte in diabetic patients.Methods Sixty patients with type 2 diabetes mellitus and fifty healthy volunteers were included in this study.Annexin V and propidiumiodide (Pl) were joined in the isolated lymphocytes and the rate of lymphocyte apoptosis was calculated with flow cytometry.Observation of the lymphocytes was done using transmission electron microscopy; mitochondria had been extracted and then mitochondrial membrane potential (MMP) was detected to assess mitochondrial function; the mRNA level of Bcl-2,cytochrome c (Cyt-C),caspase-9 and caspase-3 were analyzed by real-time reverse transcriptionpolymerase chain reaction (RT-PCR).Results Apoptosis rate of lymphocyte was significantly higher in diabetic group than that in normal control group (P <0.05).Transmission electron microscopy showed lymphocyte shrinkage and breakage,chromatin condensation and less mitochondria; a fall in MMP levels was also evident; Bcl-2 concentration was reduced and the expressions of caspase-9,caspase-3 and Cyt-C were elevated (P <0.05) in diabetic patients.Conclusions The rate of lymphocyte apoptosis was significantly higher in type 2 diabetic patients than that in normal population.Mitochondrial apoptosis pathway may play a very important role in decreasing function of lymphocyte in diabetes.

  11. A novel cisplatin mediated apoptosis pathway is associated with acid sphingomyelinase and FAS proapoptotic protein activation in ovarian cancer.

    Maurmann, L; Belkacemi, L; Adams, N R; Majmudar, P M; Moghaddas, S; Bose, R N

    2015-07-01

    Platinum-based anticancer drugs, including cisplatin and carboplatin, have been cornerstones in the treatment of solid tumors. We report here that these DNA-damaging agents, particularly cisplatin, induce apoptosis through plasma membrane disruption, triggering FAS death receptor via mitochondrial (intrinsic) pathways. Our objectives were to: quantify the composition of membrane metabolites; and determine the potential involvement of acid sphingomyelinase (ASMase) in the FAS-mediated apoptosis in ovarian cancer after cisplatin treatment. The resulting analysis revealed enhanced apoptosis as measured by: increased phosphocholine, and glycerophosphocholine; elevated cellular energetics; and phosphocreatine and nucleoside triphosphate concentrations. The plasma membrane alterations were accompanied by increased ASMase activity, leading to the upregulation of FAS, FASL and related pro-apoptotic BAX and PUMA genes. Moreover FAS, FASL, BAX, PUMA, CASPASE-3 and -9 proteins were upregulated. Our findings implicate ASMase activity and the intrinsic pathways in cisplatin-mediated membrane demise, and contribute to our understanding of the mechanisms by which ovarian tumors may become resistant to cisplatin. PMID:25846011

  12. Noscapine induces mitochondria-mediated apoptosis in human colon cancer cells in vivo and in vitro.

    Yang, Zi-Rong; Liu, Meng; Peng, Xiu-Lan; Lei, Xiao-Fei; Zhang, Ji-Xiang; Dong, Wei-Guo

    2012-05-11

    Noscapine, a phthalide isoquinoline alkaloid derived from opium, has been widely used as a cough suppressant for decades. Noscapine has recently been shown to potentiate the anti-cancer effects of several therapies by inducing apoptosis in various malignant cells without any detectable toxicity in cells or tissues. However, the mechanism by which noscapine induces apoptosis in colon cancer cells remains unclear. The signaling pathways by which noscapine induces apoptosis were investigated in colon cancer cell lines treated with various noscapine concentrations for 72 h, and a dose-dependent inhibition of cell viability was observed. Noscapine effectively inhibited the proliferation of LoVo cells in vitro (IC(50)=75 μM). This cytotoxicity was reflected by cell cycle arrest at G(2)/M and subsequent apoptosis, as indicated by increased chromatin condensation and fragmentation, the upregulation of Bax and cytochrome c (Cyt-c), the downregulation of survivin and Bcl-2, and the activation of caspase-3 and caspase-9. Moreover, in a xenograft tumor model in mice, noscapine injection clearly inhibited tumor growth via the induction of apoptosis, which was demonstrated using a TUNEL assay. These results suggest that noscapine induces apoptosis in colon cancer cells via mitochondrial pathways. Noscapine may be a safe and effective chemotherapeutic agent for the treatment of human colon cancer. PMID:22546556

  13. Apoptosis of nasopharyngeal carcinoma cell line (CNE-2) induced by neutron irradiation

    Objective: To study the apoptotic response of the nasopharyngeal carcinoma cell line (CNE-2) induced by neutron irradiation. Methods: CNE-2 cells were cultured as usual. Using the techniques of DNA agarose gel electrophoresis and DNA special fluorescent staining, the status of apoptosis in CNE-2 cells after neutron irradiation was detected. Results: It was shown that the apoptosis can be induced in CNE-2 cell after neutron radiation. Six hrs, after different doses of neutron (0/0.667/1.333/2.000/2.667/3.333 Gy) and X-ray 0/2/4/6/8/10 Gy) irradiation the apoptotic rates were 2.4%, 6.3%, 7.1%, 9.5%, 13.5%, 14.6% and 2.4%, 3.8%, 5.7%, 7.8%, 10.4%, 11.7%, respectively; at 48 hrs they were 18.3%, 21.5%, 22.8%, 29.3%, 34.2% and 13.7%, 17.6%, 21.3%, 25.6%, 28.9%, respectively. At 10 hrs after neutron irradiation the DNA ladder of apoptosis could be detected between 0.667-3.333 Gy doses in CNE-2 cells by DNA agarose gel electrophoresis. Conclusion: Neutron radiation can induce apoptosis in tumor cells. Compared with the X-ray, neutron induces apoptosis in larger extent than X-ray in the same condition; meanwhile, apoptosis after irradiation is dose and time dependent

  14. Radiation induced apoptosis and initial DNA damage are inversely related in locally advanced breast cancer patients

    DNA-damage assays, quantifying the initial number of DNA double-strand breaks induced by radiation, have been proposed as a predictive test for radiation-induced toxicity. Determination of radiation-induced apoptosis in peripheral blood lymphocytes by flow cytometry analysis has also been proposed as an approach for predicting normal tissue responses following radiotherapy. The aim of the present study was to explore the association between initial DNA damage, estimated by the number of double-strand breaks induced by a given radiation dose, and the radio-induced apoptosis rates observed. Peripheral blood lymphocytes were taken from 26 consecutive patients with locally advanced breast carcinoma. Radiosensitivity of lymphocytes was quantified as the initial number of DNA double-strand breaks induced per Gy and per DNA unit (200 Mbp). Radio-induced apoptosis at 1, 2 and 8 Gy was measured by flow cytometry using annexin V/propidium iodide. Radiation-induced apoptosis increased in order to radiation dose and data fitted to a semi logarithmic mathematical model. A positive correlation was found among radio-induced apoptosis values at different radiation doses: 1, 2 and 8 Gy (p < 0.0001 in all cases). Mean DSB/Gy/DNA unit obtained was 1.70 ± 0.83 (range 0.63-4.08; median, 1.46). A statistically significant inverse correlation was found between initial damage to DNA and radio-induced apoptosis at 1 Gy (p = 0.034). A trend toward 2 Gy (p = 0.057) and 8 Gy (p = 0.067) was observed after 24 hours of incubation. An inverse association was observed for the first time between these variables, both considered as predictive factors to radiation toxicity

  15. Somatostatin receptor subtype 2 sensitizes human pancreatic cancer cells to death ligand-induced apoptosis.

    Guillermet, Julie; Saint-Laurent, Nathalie; Rochaix, Philippe; Cuvillier, Olivier; Levade, Thierry; Schally, Andrew V; Pradayrol, Lucien; Buscail, Louis; Susini, Christiane; Bousquet, Corinne

    2003-01-01

    Somatostatin receptor subtype 2 (sst2) gene expression is lost in 90% of human pancreatic adenocarcinomas. We previously demonstrated that stable sst2 transfection of human pancreatic BxPC-3 cells, which do not endogenously express sst2, inhibits cell proliferation, tumorigenicity, and metastasis. These sst2 effects occur as a consequence of an autocrine sst2-dependent loop, whereby sst2 induces expression of its own ligand, somatostatin. Here we investigated whether sst2 induces apoptosis in sst2-transfected BxPC-3 cells. Expression of sst2 induced a 4.4- +/- 0.05-fold stimulation of apoptosis in BxPC-3 through the activation of tyrosine phosphatase SHP-1. sst2 also sensitized these cells to apoptosis induced by tumor necrosis factor alpha (TNFalpha), enhancing it 4.1- +/- 1.5-fold. Apoptosis in BxPC-3 cells mediated by TNF-related apoptosis-inducing ligand (TRAIL) and CD95L was likewise increased 2.3- +/- 0.5-fold and 7.4- +/- 2.5-fold, respectively. sst2-dependent activation and cell sensitization to death ligand-induced apoptosis involved activation of the executioner caspases, key factors in both death ligand- or mitochondria-mediated apoptosis. sst2 affected both pathways: first, by up-regulating expression of TRAIL and TNFalpha receptors, DR4 and TNFRI, respectively, and sensitizing the cells to death ligand-induced initiator capase-8 activation, and, second, by down-regulating expression of the antiapoptotic mitochondrial Bcl-2 protein. These results are of interest for the clinical management of chemoresistant pancreatic adenocarcinoma by using a combined gene therapy based on the cotransfer of genes for both the sst2 and a nontoxic death ligand. PMID:12490654

  16. Curcumin-Induced Apoptosis in Human Hepatocellular Carcinoma J5 Cells: Critical Role of Ca+2-Dependent Pathway

    Wei-Hsun Wang

    2012-01-01

    Full Text Available The antitumor effects of curcumin, a natural biologically active compound extracted from rhizomes of Curcuma longa, have been studied in many cancer cell types including human hepatocellular carcinoma (HCC. Here, we investigated the effects of Ca2+ on curcumin-induced apoptosis in human HCC J5 cells. The abrogation of mitochondrial membrane potential (ΔΨm, the increase of reactive oxygen species (ROS production, and calcium release were demonstrated with flow cytometry as early as 15 minutes after curcumin treatment. In addition, an increase level of cytochrome c in the cytoplasm which led to DNA fragmentation was observed. To verify the role of Ca2+ in curcumin-induced apoptosis, 1,2-bis(o-aminophenoxyethane-N,N,N′,N′-tetraacetic acid (BAPTA, an intracellular calcium chelator, was applied. Cell viability was increased, but ΔΨm, ROS production, activation of caspase 3, and cell death were decreased in J5 cells pretreated with BAPTA for 2 h followed by the treatment of 25 μM curcumin. These results suggest that the curcumin-induced apoptosis in human HCC J5 cells is via mitochondria-dependent pathway and is closely related to the level of intracellular accumulation of calcium.

  17. Inhibition of p53 deSUMOylation Exacerbates Puromycin Aminonucleoside-Induced Apoptosis in Podocytes

    Lingyu Wang

    2014-11-01

    Full Text Available Apoptosis is a major cause of reduced podocyte numbers, which leads to proteinuria and/or glomerulosclerosis. Emerging evidence has indicated that deSUMOylation, a dynamic post-translational modification that reverses SUMOylation, is involved in the apoptosis of Burkitt’s lymphoma cells and cardiomyocytes; however, the impact of deSUMOylation on podocyte apoptosis remains unexplored. The p53 protein plays a major role in the pathogenesis of podocyte apoptosis, and p53 can be SUMOylated. Therefore, in the present study, we evaluated the effect of p53 deSUMOylation, which is regulated by sentrin/SUMO-specific protease 1 (SENP1, on podocyte apoptosis. Our results showed that SENP1 deficiency significantly increases puromycin aminonucleoside (PAN-induced podocyte apoptosis. Moreover, SENP1 knockdown results in the accumulation of SUMOylated p53 protein and the increased expression of the p53 target pro-apoptotic genes, BAX, Noxa and PUMA, in podocytes during PAN stimulation. Thus, SENP1 may be essential for preventing podocyte apoptosis, at least partly through regulating the functions of p53 protein via deSUMOylation. The regulation of deSUMOylation may provide a novel strategy for the treatment of glomerular disorders that involve podocyte apoptosis.

  18. Grapevine fruit extract protects against radiation-induced oxidative stress and apoptosis in human lymphocyte.

    Singha, Indrani; Das, Subir Kumar

    2015-11-01

    Ionizing radiation (IR) causes oxidative stress through overwhelming generation of reactive oxygen species (ROS) in the living cells leading the oxidative damage further to biomolecules. Grapevine (Vitis vinifera L.) posses several bioactive phytochemicals and is the richest source of antioxidants. In this study, we investigated V. vinifera for its phytochemical content, enzymes profile and, ROS- and oxidant-scavenging activities. We have also studied the fruit extract of four different grapevine viz., Thompson seedless, Flame seedless, Kishmish chorni and Red globe for their radioprotective actions in human lymphocytes. The activities of ascorbic acid oxidase and catalase significantly (P skin or pulp of the same cultivar. Pretreatment with grape extracts attenuated the oxidative stress induced by 4 Gy γ-radiation in human lymphocytes in vitro. Further, γ-radiation-induced increase in caspase 3/7 activity was significantly attenuated by grape extracts. These results suggest that grape extract serve as a potential source of natural antioxidants against the IR-induced oxidative stress and also inhibit apoptosis. Furthermore, the protective action of grape depends on the source of extract (seed, skin or pulp) and type of the cultivars. PMID:26669019

  19. Grapevine fruit extract protects against radiation-induced oxidative stress and apoptosis in human lymphocyte

    Ionizing radiation (IR) causes oxidative stress through overwhelming generation of reactive oxygen species (ROS) in the living cells leading the oxidative damage further to biomolecules. Grapevine (Vitis vinifera L.) posses several bioactive phytochemicals and is the richest source of antioxidants. In this study, we investigated V. vinifera for its phytochemical content, enzymes profile and, ROS-and oxidant-scavenging activities. We have also studied the fruit extract of four different grapevine viz., Thompson seedless, Flame seedless, Kishmish chorni and Red globe for their radioprotective actions in human lymphocytes. The activities of ascorbic acid oxidase and catalase significantly (P < 0.01) differed among extracts within the same cultivar, while that of peroxidase and polyphenol oxidase did not differ significantly. The superoxide radical-scavenging activity was higher in the seed as compared to the skin or pulp of the same cultivar. Pretreatment with grape extracts attenuated the oxidative stress induced by 4 Gy γ-radiation in human lymphocytes in vitro. Further, γ-radiation-induced increase in caspase 3/7 activity was significantly attenuated by grape extracts. These results suggest that grape extract serve as a potential source of natural antioxidants against the IR-induced oxidative stress and also inhibit apoptosis. Furthermore, the protective action of grape depends on the source of extract (seed, skin or pulp) and type of the cultivars. (author)

  20. Expression of human TNF-related apoptosis-inducing ligand extracellular region in E.coli

    唐蓓; HE; Fengtian; 等

    2002-01-01

    This study is conducted to clone the cDNA encoding human TNF-related apoptosis-inducing ligand(hTRAIL)extracellular region(amino acids 41-281,hTRAIL41-281)and to express it in E.coli.The hTRAIL41-281 cDNA is amplified by reverse transcription(RT)PCR from total RNA derived from human acute promyelocytic leukemia cell line HL-60.After sequenced,the cDNA is cloned into the vector pQE-80L and transformed into E.coli DH5α to express the recombinant hTRAIL41-281(rhTRAIL41-281)induced by IPTG.The recombinant protein is analyzed by SDS-PAGE.The cloned cDNA is consistent with the cDNA sequence encoding hTRAIL41-281 reported in GenBankTM.After inducing.the hTRAIL41-281 protein is expressed,and the mass of the recombinant protein is about 30% of total bacteria protein,which demonstrates that the cDNA encoding hTRAIL41-281 is successfully cloned and expressed in E.coli.

  1. Radiation-induced apoptosis in human lymphocytes: Potential as a biological dosimeter

    We have tested the possibility of using apoptosis (programmed cell death) in human peripheral blood lymphocytes as a short-term biological dosimeter. Lymphocytes isolated from whole blood were irradiated in culture with 250 kVp x-rays or 60Co gamma rays. Two assays were used to measure apoptosis in lymphocytes after irradiation: in situ terminal deoxynucleotidyl transferase assay and fluorescence analysis of DNA unwinding assay. Similar qualitative and quantitative results were produced by the assays, supporting the notion that the fluorescence analysis of DNA unwinding assay measured DNA fragmentation associated with apoptosis. Induction of apoptosis in lymphocytes irradiated in vitro was proportional to dose and could be detected following exposures as low as 0.05 Gy. Lymphocytes irradiated in vitro was proportional to dose and could be detected following exposures as low as 0.05 Gy. Lymphocytes from individual donors had reproducible dose responses. There was, however, variation between donors. X-ray and gamma-ray exposures induced similar levels of apoptosis at similar doses. The induction kinetics of apoptosis in vitro indicate a maximum is reached about 72 h after irradiation. In conclusion, the in vitro experimental evidence indicates that radiation-induced apoptosis in human lymphocytes has the kinetics, sensitivity, and reproductibility to be a potential biological dosimeter. 29 refs., 5 figs

  2. Sarcolemmal ATP-sensitive potassium channel protects cardiac myocytes against lipopolysaccharide-induced apoptosis.

    Zhang, Xiaohui; Zhang, Xiaohua; Xiong, Yiqun; Xu, Chaoying; Liu, Xinliang; Lin, Jian; Mu, Guiping; Xu, Shaogang; Liu, Wenhe

    2016-09-01

    The sarcolemmal ATP-sensitive K+ (sarcKATP) channel plays a cardioprotective role during stress. However, the role of the sarcKATP channel in the apoptosis of cardiomyocytes and association with mitochondrial calcium remains unclear. For this purpose, we developed a model of LPS-induced sepsis in neonatal rat cardiomyocytes (NRCs). The TUNEL assay was performed in order to detect the apoptosis of cardiac myocytes and the MTT assay was performed to determine cellular viability. Exposure to LPS significantly decreased the viability of the NRCs as well as the expression of Bcl-2, whereas it enhanced the activity and expression of the apoptosis-related proteins caspase-3 and Bax, respectively. The sarcKATP channel blocker, HMR-1098, increased the apoptosis of NRCs, whereas the specific sarcKATP channel opener, P-1075, reduced the apoptosis of NRCs. The mitochondrial calcium uniporter inhibitor ruthenium red (RR) partially inhibited the pro-apoptotic effect of HMR-1098. In order to confirm the role of the sarcKATP channel, we constructed a recombinant adenovirus vector carrying the sarcKATP channel mutant subunit Kir6.2AAA to inhibit the channel activity. Kir6.2AAA adenovirus infection in NRCs significantly aggravated the apoptosis of myocytes induced by LPS. Elucidating the regulatory mechanisms of the sarcKATP channel in apoptosis may facilitate the development of novel therapeutic targets and strategies for the management of sepsis and cardiac dysfunction. PMID:27430376

  3. APOPTOSIS INDUCED BY HYPERTHERMIA IN HUMAN GLIOBLASTOMA CELL LINE AND MURINE GLIOBLASTOMA

    2000-01-01

    Objective: To study the role of apoptosis in tumor cell of malignant glioma death following treatment with hyperthermia and calcium ionophore. Methods: The apoptosis induced by hyperthermia and calcium ionophore, A23187, in human glioblastoma cell line TJ905 and murine glioblastoma G422 was evaluated by characteristic findings in DNA agarose gel electrophresis, ultrastructural examination and flow cytometric analysis. Results: Apoptosis could be induced by moderate hyperthermia, but not by mild hyperthermia, calcium ionophore enhanced significantly the effect of mild hyperthermia on the induction of apoptosis. Conclusion: This result indicates that apoptotic cell death is one of the mechanisms of hyperthermic therapy for malignant glioma and taking measures to increase the cytolic calcium may enhance the effect of hyperthermia.

  4. Role of Calcium Ion in Apoptosis of MD Cancer Cells Induced by Arsenic Trioxide

    ZHANG Jiuli; WANG Jintao; XU Shiwen

    2008-01-01

    In order to observe the role of calcium ion in apoptosis of MD cancer cells induced by arsenic trioxide, inhibition percentage was detected by MTT assay;morphology changes were examined by fluorescence microscope;apoptosis was examined by DNA Ladder;[Ca2+]i was investigated by spectrofluorimeter in vitro on MDCC-MSB1 cells. The results showed that As2O3 inhibited the proliferation of MDCC-MSB1 cells in concentration dependent manner (P<0.05 or P<0.01);typical apoptosis character was observed by fluorescence microscope;DNA Ladder was observed;the [Ca2+]i was elevated significantly after the treatment of As203 (P<0.05 or P<0.01) and showed a dose-dependent manner. It is concluded that the calcium may play an important role in apoptosis of MD cancer cells induced by arsenic trioxide.

  5. [Viral transfer of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) in gene therapy].

    Wędrowska, Ewelina; Wandtke, Tomasz; Dyczek, Andrzej; Woźniak, Joanna

    2015-01-01

    Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) selectively induces carcinoma cell death through the extrinsic pathway of apoptosis. Preclinical trials of gene therapy have been conducted using viral transfer of the TRAIL transgene into prostate, bladder, breast, kidney, liver, non-small cell lung cancer and also glioblastoma cells. Experiments in vitro demonstrated the extensive apoptosis of target cells as well as frequent disease regression or remission. TRAIL transfer did not show any side effects, opposite to chemotherapy. Encouraging results of TRAIL-related gene therapy were observed in rheumatoid arthritis and type 1 diabetes. Adenoviral vectors (AdV) encoding TRAIL are the most promising tool in anti-tumor therapy. They have undergone numerous modifications by increasing transfection efficiency and transgene expression in target cells. However, only one clinical phase I trial has been performed. AdV encoding the TRAIL transgene caused local inflammation and apoptosis in patients with prostate cancer. PMID:27259213

  6. The role of osteocyte apoptosis in cancer chemotherapy-induced bone loss.

    Shandala, Tetyana; Shen Ng, Yeap; Hopwood, Blair; Yip, Yuen-Ching; Foster, Bruce K; Xian, Cory J

    2012-07-01

    Intensive cancer chemotherapy leads to significant bone loss, the underlying mechanism of which remains unclear. The objective of this study was to elucidate mechanisms for effect of the commonly used anti-metabolite methotrexate (MTX) on osteocytes and on general bone homeostasis. The current study in juvenile rats showed that MTX chemotherapy caused a 4.3-fold increase in the number of apoptotic osteocytes in tibial metaphysis, which was accompanied by a 1.8-fold increase in the number of tartrate-resistant acid phosphatase-positive bone resorbing osteoclasts, and a 35% loss of trabecular bone. This was associated with an increase in transcription of the osteoclastogenic cytokines IL-6 (10-fold) and IL-11 (2-fold). Moreover, the metaphyseal bone of MTX-treated animals exhibited a 37.6% increase in the total number of osteocytes, along with 4.9-fold higher expression of the DMP-1 transcript. In cultured osteocyte-like MLO-Y4 cells, MTX treatment significantly increased caspase-3-mediated apoptosis, which was accompanied by the formation of plasma membrane-born apoptotic bodies and an increase in IL-6 (24-fold) and IL-11 (29-fold) mRNA expression. Conditioned media derived from MTX-treated MLO-Y4 cells was twice as strong as untreated media in its capacity to induce osteoclast formation in primary bone marrow osteoclast precursors. Thus, our in vivo and in vitro data suggested that MTX-induced apoptosis of osteocytes caused higher recruitment of DMP-1 positive osteocytes and increased osteoclast formation, which could contribute towards the loss of bone homeostasis in vivo. PMID:21938727

  7. Taurine inhibits serum deprivation-induced osteoblast apoptosis via the taurine transporter/ERK signaling pathway

    Lei-Yi Zhang; Yue-Ying Zhou; Fei Chen; Bing Wang; Jing Li; You-Wen Deng; Wei-Dong Liu; Zheng-Guang Wang; Ya-Wei Li; Dong-Zhe Li; Guo-Hua Lv; Bang-Liang Yin

    2011-01-01

    Taurine has positive effects on bone metabolism. However, the effects of taurine on osteoblast apoptosis in vitro have not been reported. The aim of this study was to investigate the activity of taurine on apoptosis of mouse osteoblastic MC3T3-E1 cells. The data showed that 1, 5, 10, or 20 mM taurine resulted in 16.7, 34.2, 66.9, or 63.75% reduction of MC3T3-E1 cell apoptosis induced by the serum deprivation (serum-free α-MEM), respectively. Taurine (1, 5, or 10 mM) also reduced cytochrome c ...

  8. HUHS1015 PROMOTES AUTOPHAGIC XIAP DEGRADATION TO INDUCE APOPTOSIS OF GASTROINTESTINAL CANCER CELLS

    Tomoyuki Nishizaki

    2016-01-01

    The present study aimed at understanding the mechanism underlying HUHS1015-induced apoptosis of MKN45 gastric cancer and Caco-2 colonic cell, Apoptosis, cancer cell lines.  HUHS1015 apparently reduced presence of mRNA protein of X-linked inhibitor of apoptosis protein (XIAP) in a treatment time Autophagy  (10-60 min)-dependent manner.   The reduction of XIAP protein was prevented by the autophagy inhibitors 3-methyladenine and bafilomycin A1.  XIAP knock-down signi...

  9. Polycyclic’ Aromatic Hydrocarbon Induced Intracellular Signaling and Lymphocyte Apoptosis

    Schneider, Alexander M.

    lymphocytes. Our experiments on preB lymphocytes supported by stromal cells suggest that apoptosis is one of the mechanisms for PAH immunosuppression. It could be either due to direct effect of the PAH on the B cells, via stromal cell signaling. Ubiquitous PAH-like toxin, fluoranthene, was tested for it...

  10. alpha-Amanitin induced apoptosis in primary cultured dog hepatocytes.

    Adam Szelag

    2010-06-01

    Full Text Available Amatoxin poisoning is caused by mushroom species belonging to the genera Amanita, Galerina and Lepiota with the majority of lethal mushroom exposures attributable to Amanita phalloides. High mortality rate in intoxications with these mushrooms is principally a result of the acute liver failure following significant hepatocyte damage due to hepatocellular uptake of amatoxins. A wide variety of amatoxins have been isolated; however, alpha-amanitin (alpha-AMA appears to be the primary toxin. Studies in vitro and in vivo suggest that alpha-AMA does not only cause hepatocyte necrosis, but also may lead to apoptotic cell death. The objective of this study was to evaluate the complex hepatocyte apoptosis in alpha-AMA cytotoxicity. All experiments were performed on primary cultured canine hepatocytes. The cells were incubated for 12 h with alpha-AMA at a final concentration of 1, 5, 10 and 20 microM. Viability test (MTT assay, apoptosis evaluation (TUNEL reaction, detection of DNA laddering and electron microscopy were performed at 6 and 12 h of exposure to alpha-AMA. There was a clear correlation between hepatocyte viability, concentration of alpha-AMA and time of exposure to this toxin. The decline in cultured dog hepatocyte viability during the exposure to alpha-AMA is most likely preceded by enhanced cellular apoptosis. Our results demonstrate that apoptosis might contribute to pathogenesis of the severe liver injury in the course of amanitin intoxication, particularly during the early phase of poisoning.

  11. Brain death induces apoptosis in donor liver of the rat

    van der Hoeven, JAB; Moshage, H; Schuurs, T; Nijboer, M; van Schilfgaarde, R; Ploeg, RJ

    2003-01-01

    Background. A difference in short- and long-term function between living-related and cadaveric donor organs is consistently shown in kidney- and liver-transplant studies. We hypothesize that this is caused by induction of apoptosis and inflammation of the potential graft because of the phase of brai

  12. Succinobucol induces apoptosis in vascular smooth muscle cells

    Midwinter, R.G.; Maghzal, G.; Dennis, J.M.; Wu, B.J.; Cai, H.; Kapralov, A.A.; Belikova, N.A.; Tyurina, Y.Y.; Dong, L. F.; Khachigian, L.; Neužil, Jiří; Kagan, V.E.; Stocker, R.

    2012-01-01

    Roč. 52, č. 5 (2012), s. 871-879. ISSN 0891-5849 R&D Projects: GA ČR(CZ) GAP301/10/1937 Institutional research plan: CEZ:AV0Z50520701 Keywords : reactive oxygen species * free radicals * apoptosis Subject RIV: EA - Cell Biology Impact factor: 5.271, year: 2012

  13. Daxx inhibits stress-induced apoptosis in cardiac myocytes

    Zobalová, Renata; Swettenham, E.; Chladová, Jaromíra; Dong, L.F.; Neužil, Jiří

    2008-01-01

    Roč. 13, č. 6 (2008), s. 263-270. ISSN 1351-0002 R&D Projects: GA ČR(CZ) GA305/07/1008 Institutional research plan: CEZ:AV0Z50520701 Keywords : Daxx * apoptosis * oxidative stress Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.013, year: 2008

  14. ATF2 knockdown reinforces oxidative stress-induced apoptosis in TE7 cancer cells

    Walluscheck, Diana; Poehlmann, Angela; Hartig, Roland; Lendeckel, Uwe; Schönfeld, Peter; Hotz-Wagenblatt, Agnes; Reissig, Kathrin; Bajbouj, Khuloud; Roessner, Albert; Schneider-Stock, Regine

    2013-01-01

    Cancer cells showing low apoptotic effects following oxidative stress-induced DNA damage are mainly affected by growth arrest. Thus, recent studies focus on improving anti-cancer therapies by increasing apoptosis sensitivity. We aimed at identifying a universal molecule as potential target to enhance oxidative stress-based anti-cancer therapy through a switch from cell cycle arrest to apoptosis. A cDNA microarray was performed with hydrogen peroxide-treated oesophageal squamous epithelial can...

  15. DNA Damage, Apoptosis and Langerhans cells – Activators of UV-induced Immune Tolerance

    Timares, Laura; Katiyar, Santosh; Elmets, Craig A.

    2008-01-01

    Solar ultraviolet radiation (UVR) is highly mutagenic but is only partially absorbed by the outer stratum corneum of the epidermis. UVR can penetrate into the deeper layers of the epidermis, depending on melanin content, where it induces DNA damage and apoptosis in epidermal cells, including those in the germinative basal layer. The cellular decision to initiate either the cellular repair processes or undergo apoptosis has evolved to balance the acute need to maintain skin barrier function wi...

  16. Apoptosis is induced in bovine satellite muscle cells after removal of available oxygen

    Andersen, Petter Vejle

    2013-01-01

    Abstract Post-mortem tenderisation of meat is a complex process, of which all the details are far from understood. Cell death by apoptosis is recently proposed as a novel mechanism in this process. The main aim of this study was to investigate if bovine satellite muscle cells, cultivated in vitro, would induce apoptosis when oxygen was removed from the incubation medium. Satellite muscle cells was seeded out in Entactin-Collagen IV-Laminin (ECL) coated culture wells and allowed to diffe...

  17. Tripeptidyl Peptidase II Promotes Maturation of Caspase-1 in Shigella flexneri-Induced Macrophage Apoptosis

    Hilbi, Hubert; Puro, Robyn J.; Zychlinsky, Arturo

    2000-01-01

    The invasive enteropathogenic bacterium Shigella flexneri activates apoptosis in macrophages. Shigella-induced apoptosis requires caspase-1. We demonstrate here that tripeptidyl peptidase II (TPPII), a cytoplasmic, high-molecular-weight protease, participates in the apoptotic pathway triggered by Shigella. The TPPII inhibitor Ala-Ala-Phe-chloromethylketone (AAF-cmk) and clasto-lactacystin β-lactone (lactacystin), an inhibitor of both TPPII and the proteasome, protected macrophages from Shigel...

  18. Rapid selection against arbovirus-induced apoptosis during infection of a mosquito vector

    O’Neill, Katelyn; Olson, Bradley J. S. C.; Huang, Ning; Unis, Dave; Clem, Rollie J.

    2015-01-01

    Understanding the factors that cause mosquitoes to resist arbovirus infection could lead to new strategies to control disease transmission. One antiviral response that may play a role in mosquito immunity is apoptosis, a type of cell suicide that is often induced by virus infection. However, apoptosis is rarely seen in arbovirus-infected mosquitoes. To understand why, we infected mosquitoes with an arbovirus that expresses a proapoptotic gene called reaper and found that the Reaper-expressing...

  19. Probiotic sonicates selectively induce mucosal immune cells apoptosis through ceramide generation via neutral sphingomyelinase.

    Sandra Angulo

    Full Text Available BACKGROUND: Probiotics appear to be beneficial in inflammatory bowel disease, but their mechanism of action is incompletely understood. We investigated whether probiotic-derived sphingomyelinase mediates this beneficial effect. METHODOLOGY/PRINCIPAL FINDINGS: Neutral sphingomyelinase (NSMase activity was measured in sonicates of the probiotic L. brevis (LB and S. thermophilus (ST and the non-probiotic E. coli (EC and E. faecalis (EF. Lamina propria mononuclear cells (LPMC were obtained from patients with Crohn's disease (CD and Ulcerative Colitis (UC, and peripheral blood mononuclear cells (PBMC from healthy volunteers, analysing LPMC and PBMC apoptosis susceptibility, reactive oxygen species (ROS generation and JNK activation. In some experiments, sonicates were preincubated with GSH or GW4869, a specific NSMase inhibitor. NSMase activity of LB and ST was 10-fold that of EC and EF sonicates. LB and ST sonicates induced significantly more apoptosis of CD and UC than control LPMC, whereas EC and EF sonicates failed to induce apoptosis. Pre-stimulation with anti-CD3/CD28 induced a significant and time-dependent increase in LB-induced apoptosis of LPMC and PBMC. Exposure to LB sonicates resulted in JNK activation and ROS production by LPMC. NSMase activity of LB sonicates was completely abrogated by GW4869, causing a dose-dependent reduction of LB-induced apoptosis. LB and ST selectively induced immune cell apoptosis, an effect dependent on the degree of cell activation and mediated by bacterial NSMase. CONCLUSIONS: These results suggest that induction of immune cell apoptosis is a mechanism of action of some probiotics, and that NSMase-mediated ceramide generation contributes to the therapeutic effects of probiotics.

  20. Marijuana smoke condensate induces p53-mediated apoptosis in human lung epithelial cells.

    Kim, Ha Ryong; Jung, Mi Hyun; Lee, Soo Yeun; Oh, Seung Min; Chung, Kyu Hyuck

    2013-01-01

    Since the largely abused worldwide used of marijuana, there have been many ongoing debates regarding the adverse health effects of marijuana smoking. Marijuana smoking was recently proved to cause pulmonary toxicity by inducing genotoxic effects or generating reactive oxygen species. Because p53, a tumor suppressor gene, has an important pathophysiologic role in the regulation of lung epithelial cell DNA damage responses, we hypothesized that p53 may be involved in the oxidative stress-mediated apoptosis induced by marijuana smoking. First, we confirmed that marijuana smoke condensate (MSC) induces oxidative stress in BEAS-2B cells. We observed that reactive oxygen species (ROS) generation was increased by MSC in the DCFH-DA assay. Also, antioxidant enzyme (superoxide dismutase, catalase) activity and their mRNA expressions were up-regulated by MSC. Second, we investigated p53 involvement in the MSC-induced apoptotic pathway in BEAS-2B cells. The results showed that MSC increased caspase-3 activation and DNA fragmentation as markers of apoptosis. In addition, the mRNA levels of apoptosis-related genes (p53 and Bax) were increased by MSC and phospho-p53, along with the increase of Bax protein expression by MSC. Apoptosis and apoptosis-related gene expression were partially blocked by an inhibitor of p53-dependent transcriptional activation (pifithrin-α). The results indicate that p53 plays a role in MSC-induced apoptosis. Taken together, the findings of the present study suggest that MSC partially induces p53-mediated apoptosis through ROS generation in human lung epithelial cells and this may have broader implications for our understanding of pulmonary diseases. PMID:23665932

  1. Interdependence of Bad and Puma during ionizing-radiation-induced apoptosis.

    Cristhian Toruno

    Full Text Available Ionizing radiation (IR-induced DNA double-strand breaks trigger an extensive cellular signaling response that involves the coordination of hundreds of proteins to regulate DNA repair, cell cycle arrest and apoptotic pathways. The cellular outcome often depends on the level of DNA damage as well as the particular cell type. Proliferating zebrafish embryonic neurons are highly sensitive to IR-induced apoptosis, and both p53 and its transcriptional target puma are essential mediators of the response. The BH3-only protein Puma has previously been reported to activate mitochondrial apoptosis through direct interaction with the pro-apoptotic Bcl-2 family proteins Bax and Bak, thus constituting the role of an "activator" BH3-only protein. This distinguishes it from BH3-only proteins like Bad that are thought to indirectly promote apoptosis through binding to anti-apoptotic Bcl-2 family members, thereby preventing the sequestration of activator BH3-only proteins and allowing them to directly interact with and activate Bax and Bak. We have shown previously that overexpression of the BH3-only protein Bad in zebrafish embryos supports normal embryonic development but greatly sensitizes developing neurons to IR-induced apoptosis. While Bad has previously been shown to play only a minor role in promoting IR-induced apoptosis of T cells in mice, we demonstrate that Bad is essential for robust IR-induced apoptosis in zebrafish embryonic neural tissue. Moreover, we found that both p53 and Puma are required for Bad-mediated radiosensitization in vivo. Our findings show the existence of a hierarchical interdependence between Bad and Puma whereby Bad functions as an essential sensitizer and Puma as an essential activator of IR-induced mitochondrial apoptosis specifically in embryonic neural tissue.

  2. NFAT2 mediates high glucose-induced glomerular podocyte apoptosis through increased Bax expression

    Background: Hyperglycemia promotes podocyte apoptosis and plays a key role in the pathogenesis of diabetic nephropathy. However, the mechanisms that mediate hyperglycemia-induced podocyte apoptosis is still far from being fully understood. Recent studies reported that high glucose activate nuclear factor of activated T cells (NFAT) in vascular smooth muscle or pancreatic β-cells. Here, we sought to determine if hyperglycemia activates NFAT2 in cultured podocyte and whether this leads to podocyte apoptosis. Meanwhile, we also further explore the mechanisms of NFAT2 activation and NFAT2 mediates high glucose-induced podocyte apoptosis. Methods: Immortalized mouse podocytes were cultured in media containing normal glucose (NG), or high glucose (HG) or HG plus cyclosporine A (a pharmacological inhibitor of calcinerin) or 11R-VIVIT (a special inhibitor of NFAT2). The activation of NFAT2 in podocytes was detected by western blotting and immunofluorescence assay. The role of NFAT2 in hyperglycemia-induced podocyte apoptosis was further evaluated by observing the inhibition of NFAT2 activation by 11R-VIVIT using flow cytometer. Intracellular Ca2+ was monitored in HG-treated podcocytes using Fluo-3/AM. The mRNA and protein expression of apoptosis gene Bax were measured by real time-qPCR and western blotting. Results: HG stimulation activated NFAT2 in a time- and dose-dependent manner in cultured podocytes. Pretreatment with cyclosporine A (500 nM) or 11R-VIVIT (100 nM) completely blocked NFAT2 nuclear accumulation. Meanwhile, the apoptosis effects induced by HG were also abrogated by concomitant treatment with 11R-VIVIT in cultured podocytes. We further found that HG also increased [Ca2+]i, leading to activation of calcineurin, and subsequent increased nuclear accumulation of NFAT2 and Bax expression in cultured podocytes. Conclusion: Our results identify a new finding that HG-induced podocyte apoptosis is mediated by calcineurin/NFAT2/Bax signaling pathway, which may

  3. Octreotide inhibits proliferation and induces apoptosis of hepatocellular carcinoma cells

    Hai-lin LIU; Li HUO; Lei WANG

    2004-01-01

    AIM: To study the effect of octreotide on cell proliferation and apoptosis in different hepatocellular carcinoma (HCC) cells and hepatocytes. METHODS: The proliferation of HCC cells (HepG2, SMMC-7721) and hepatocytes (L-02) was determined by MTT assay. Apoptosis was detected either by fluorescent staining, transmission electron microscopy or flow cytometry. The content of AFP in the supernatant of cultured HCC cells was determined by electrochemiluminescence immunoassay. The expression of SSTR subtypes was identified by RT-PCR.RESULTS: The proliferation of HCC cells and L-02 cells was inhibited significantly by octreotide (0.25, 0.5, 1.0,2.0 and 4.0 mg/L). However, the apoptosis of HCC cells markedly increased in a concentration-dependent manner.Both the apoptosis index and the percentage of apoptotic cells in L-02 cells were significantly lower than those of HepG2 and SMMC-7721 cells. The content of AFP in the supematant of cultured HepG2 cells treated with octreotide was also statistically reduced. Furthermore, SSTR2 and SSTR4 were positive in both the hepatocellular carcinoma cells and in the L-02 cells. SSTR3 was only expressed in the two heptatocellular carcinoma cells, and SSTR5 was found in the SMMC-7721 cells. No SSTR1 was detected either in HCC cells or L-02 cells. CONCLUSIONS:Apoptosis induction is a major mechanism of octreotide inhibition on hepatocellular cells. SSTR3 is expressed in the HCC cells, but not in the L-02 cells, which suggests a molecular basis for the HCC-selective effects of octreotide.

  4. Acute ethanol induces apoptosis by stimulating TRPC6 via elevation of superoxide in oxygenated podocytes

    Lu, Xiao-Yu; Liu, Bing-Chen; Wang, Li-Hua; Yang, Li-li; Bao, Qing; Zhai, Yu-Jia; Alli, Abdel A.; Thai, Tiffany L.; Eaton, Douglas C.; WANG Wei-zhi; Ma, He-Ping

    2015-01-01

    Our recent studies indicate that hydrogen peroxide (H2O2) only at high concentrations can cause oxidative stress in renal epithelial cells and induce apoptosis of podocytes. Consistently, the present study shows that H2O2, even at 1 mM, failed to induce intracellular oxidative stress and apoptosis of the podocytes due to efficient activity of catalase, an enzyme which degrades H2O2 to produce water and oxygen (O2). However, H2O2 acted as a source of O2 to allow acute ethanol to induce superox...

  5. Staphylococcus aureus Panton-Valentine leukocidin directly targets mitochondria and induces Bax-independent apoptosis of human neutrophils

    Genestier, Anne-Laure; Michallet, Marie-Cécile; Prévost, Gilles; Bellot, Gregory; Chalabreysse, Lara; Peyrol, Simone; Thivolet, Françoise; Etienne, Jerome; Lina, Gérard; Vallette, François M.; Vandenesch, François; Genestier, Laurent

    2005-01-01

    Panton-Valentine leukocidin (PVL) is a pore-forming toxin secreted by Staphylococcus aureus that has recently been associated with necrotizing pneumonia. In the present study, we report that in vitro, PVL induces polymorphonuclear cell death by necrosis or by apoptosis, depending on the PVL concentration. PVL-induced apoptosis was associated with a rapid disruption of mitochondrial homeostasis and activation of caspase-9 and caspase-3, suggesting that PVL-induced apoptosis is preferentially m...

  6. Dioscin induces cancer cell apoptosis through elevated oxidative stress mediated by downregulation of peroxiredoxins.

    Wang, Zhiyu; Cheng, Yue; Wang, Neng; Wang, Dong Mei; Li, Ying Wei; Han, Feng; Shen, Jian Gang; Yang, De Po; Guan, Xin Yuan; Chen, Jian-Ping

    2012-02-01

    Dioscin has been shown to promote anticancer activity against several forms of cancers. However, its detailed molecular mechanisms have not been clearly clarified.In this study, we demonstrate that dioscin induces apoptosis in cancer cells through the induction of oxidative stress. Treatment with cancer cells in vitro with dioscin resulted in rapid generation of reactive oxygen species (ROS) and the induction of mitochondrial pathway apoptosis in human esophageal cancer cell line Kyse510. Inhibition of oxidative stress by the antioxidant N-acetylcysteine blocked the induction of apoptosis by dioscin, indicating that ROS generation is the primary mechanism responsible for the proapoptotic activity of dioscin. Proteomic analysis and protein gel blotting further revealed peroxiredoxins 1 and 6 (PRDX 1 and 6), which are implicated in ROS metabolism and apoptosis, were associated with the anticancer effects of dioscin. Meanwhile, overexpression of PRDX 1 and 6 significantly blocked the elevated ROS and apoptosis induced by dioscin. In conclusion, we suggest that PRDX1 and PRDX6 are key targets in the process of dioscin-induced apoptosis that involves intracellular elevated ROS. PMID:22231406

  7. MECHANISM OF TAXOL-INDUCED APOPTOSIS IN HUMAN BREAST CANCER CELLS

    Chen Lirong; Zheng Shu; MC Willingham; Fan Weimin

    1998-01-01

    Objective: To investigate the mechanism by which taxol induces apoptosis in human breast cancer cells.Methods: Cell morphology, agarose gel electrophoresis,flow cytometry, video time-lapse monitor and Western blot were performed for investigating taxol-induced apoptosis in human breast cancer cells (BCap 37).Results: BCap 37 cells treated with taxol (100 nm) underwent the arrests of cell mitosis at metaphase of mitosis and induction of apoptosis. Apoptotic cells demonstrated cell shrinkage, condensation or fragmentation of chromosomes. Nuclear DNA of apoptotic cells displayed ladder bands characteristic of internucleosomal DNA fragmentation. The expression of bcl-2, inhibitor of apotosis, was decreased with modification, while that of bax, inducer of apoptosis, increased only at early stage of the apoptotic pathway and decreased later. Conclusion:In human breast cancer cells the induction of apoptosis by taxol was closely associated with mitotic arrest of cell cycle, and altered expressions of bcl-2 and bax gene possibly played an important role in regulating taxolinduced apoptosis.

  8. Biological dosimetry: the potential use of radiation-induced apoptosis in human T-lymphocytes

    An assay for biological dosimetry based on the induction of apoptosis in human T-lymphocytes is described. Radiation-induced apoptosis was assessed by flow cytometric identification of cells displaying apoptosis-associated DNA condensation. CD4 and CD8 T-lymphocytes were analysed. They were recognized on the basis of their cell-surface antigens. Four parameters were measured for both cell types: cell size, granularity, antigen immunofluorescence and DNA content. Apoptosis was quantified as the fraction of CD4-, or CD8-positive cells with a characteristic reduction of cell size and DNA content. At doses below 1 Gy, levels of radiation-induced apoptosis increased for up to 5 days after irradiation. Optimal dose discrimination was observed 4 days after irradiation, at which time the dose-response curves were linear, with a slope of 8% ± 0.5% per 0.1 Gy. In controlled, dose-response experiments the lowest dose level at which the radiation-induced apoptosis frequency was still significantly above control was 0.05 Gy. After 5 days post-irradiation incubation, intra- and interdonor variations were measured and found to be similar; thus, apoptotic levels depend more on the dose than on the donor. The results demonstrate the potential of this assay as a biological dosimeter. (orig.)

  9. Lack of EGCG Effects on Radiation-Induced Apoptosis of Mice Splenocytes

    The modification of radiation-induced apoptosis by EGCG, known as antioxidants or oxidants, was studied in mice spleens irradiated with a lethal dose. Materials and Methods: Male C57BL/6 mice were divided into control, irradiation-only, and EGCG (100 mg/kg i.p. 1 h before irradiation) pretreatment groups. The mice were irradiated with a single whole-body dose of 7 Gy. The apoptosis in the spleens after irradiation of the lethal dose were analyzed by TUNEL assay. In addition, the expression levels of the Bax and Bcl-2 proteins were quantified using a Western blotting method. Results: The induction of apoptosis was detected in the splenic white pulp. The highest level of apoptosis was detected at 8 hours after irradiation. No significant difference was identified by the apoptotic index (53.9% vs. 52.1%, p=0.328) and relative Bax protein expression (0.86 vs. 0.81, p=0.335), between the irradiation-only and EGCG pretreatment group, respectively. However, a lower Bax/Bcl-2 ratio (1.64 vs. 0.97, p=0.037) and higher relative expression level of Bcl-2 protein (0.57 vs. 0.82, p=0.037) was measured in the EGCG pretreatment group. Conclusion: The EGCG pretreatment neither decreased the radiation-induced apoptosis in mice splenocytes, nor induced additional apoptosis

  10. Lack of EGCG Effects on Radiation-Induced Apoptosis of Mice Splenocytes

    Jang, Seong Soon; Lee, Heui Kwan [The Catholic University College of Medicine, Seoul (Korea, Republic of)

    2008-09-15

    The modification of radiation-induced apoptosis by EGCG, known as antioxidants or oxidants, was studied in mice spleens irradiated with a lethal dose. Materials and Methods: Male C57BL/6 mice were divided into control, irradiation-only, and EGCG (100 mg/kg i.p. 1 h before irradiation) pretreatment groups. The mice were irradiated with a single whole-body dose of 7 Gy. The apoptosis in the spleens after irradiation of the lethal dose were analyzed by TUNEL assay. In addition, the expression levels of the Bax and Bcl-2 proteins were quantified using a Western blotting method. Results: The induction of apoptosis was detected in the splenic white pulp. The highest level of apoptosis was detected at 8 hours after irradiation. No significant difference was identified by the apoptotic index (53.9% vs. 52.1%, p=0.328) and relative Bax protein expression (0.86 vs. 0.81, p=0.335), between the irradiation-only and EGCG pretreatment group, respectively. However, a lower Bax/Bcl-2 ratio (1.64 vs. 0.97, p=0.037) and higher relative expression level of Bcl-2 protein (0.57 vs. 0.82, p=0.037) was measured in the EGCG pretreatment group. Conclusion: The EGCG pretreatment neither decreased the radiation-induced apoptosis in mice splenocytes, nor induced additional apoptosis.

  11. Apoptosis and radiosensitivity induced by N-acety1 phytosphingosine, in human cancer cell line

    Kim, Y. H.; Kim, K. S.; Han, Y. S.; Jeon, S. J.; Song, J. Y.; Jung, I. S.; Hong, S. H.; Yun, Y. S. [Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of); Park, J. S. [Doosan Biotech, Yongin (Korea, Republic of)

    2004-07-01

    Ceramide is a key lipid molecule in signal transduction with a role in various regulatory pathways including differentiation, proliferation and especially apoptosis. Ionizing radiation-induced apoptosis is associated with accumulation of ceramide, and the sphingomyelinase deficiency results in radioresistance. We investigated the exogenous treatment of N-acetyl-phytosphingosine (NAPS), an analogue of N-acetyl-sphingosine (C{sub 2}-Ceramide), and C{sub 2}-ceramide exert apoptotic effect on human T cell lymphoma Jurkat cells and breast cancer cell line MDA-MB-231. NAPS and C{sub 2}-Ceramide has cytotoxic effect in time- and dose-dependent manner, and increased caspase-3, 8 activity. However, NAPS induced apoptosis more effectively, and increased caspase activity induced by NAPS is more higher than C{sub 2}-ceramide. Moreover, NAPS decreased clonogenicity of irradiated cells and increased radiation-induced apoptosis significantly. Increased cell death by irradiation in the presence of NAPS is owing to the increase of caspase activity. These data suggest that NAPS might be used for lead as a new type of radiosensitizing agent increasing radiation-induced apoptosis.

  12. Protective effect of lithium chloride against hypoglycemia-induced apoptosis in neuronal PC12 cell.

    Xu, Yuzhen; Wang, Qian; Li, Dongsheng; Wu, Zhenghua; Li, Dawei; Lu, Kaili; Zhao, Yuwu; Sun, Yongning

    2016-08-25

    Hypoglycemia is defined by an arbitrary plasma glucose level lower than 3.9mmol/L and is a most common and feared adverse effect of treatment of diabetes mellitus. Emerging evidences demonstrated that hypoglycemia could induce enhanced apoptosis. Lithium chloride (LiCl), a FDA approved drug clinically used for treatment of bipolar disorders, is recently proven having neuroprotection against various stresses in the cellular and animal models of neural disorders. Here, we have established a hypoglycemia model in vitro and assessed the neuroprotective efficacy of LiCl against hypoglycemia-induced apoptosis and the underlying cellular and molecular mechanisms. Our studies showed that LiCl protects against hypoglycemia-induced neurotoxicity in vitro. Exposure to hypoglycemia results in enhanced apoptosis and the underlying cellular and molecular mechanisms involved inhibition of the canonical Wnt signaling pathway by decreasing wnt3a levels, β-catenin levels and increasing GSK-3β levels, which was confirmed by the use of Wnt-specific activator LiCl. Hypoglycemia-induced apoptosis were significantly reversed by LiCl, leading to increased cell survival. LiCl also alters the expression/levels of the Wnt pathway genes/proteins, which were reduced due to exposed to hypoglycemia. Overall, our results conclude that LiCl provides neuroprotection against hypoglycemia-induced apoptosis via activation of the canonical Wnt signaling pathway. PMID:27241942

  13. Bach1 Induces Endothelial Cell Apoptosis and Cell-Cycle Arrest through ROS Generation

    Wang, Xinhong; Liu, Junxu; Jiang, Li; Wei, Xiangxiang; Niu, Cong; Wang, Rui; Zhang, Jianyi; Yao, Kang

    2016-01-01

    The transcription factor BTB and CNC homology 1 (Bach1) regulates genes involved in the oxidative stress response and cell-cycle progression. We have recently shown that Bach1 impairs cell proliferation and promotes apoptosis in cultured endothelial cells (ECs), but the underlying mechanisms are largely uncharacterized. Here we demonstrate that Bach1 upregulation impaired the blood flow recovery from hindlimb ischemia and this effect was accompanied both by increases in reactive oxygen species (ROS) and cleaved caspase 3 levels and by declines in the expression of cyclin D1 in the injured tissues. We found that Bach1 overexpression induced mitochondrial ROS production and caspase 3-dependent apoptosis and its depletion attenuated H2O2-induced apoptosis in cultured human microvascular endothelial cells (HMVECs). Bach1-induced apoptosis was largely abolished when the cells were cultured with N-acetyl-l-cysteine (NAC), a ROS scavenger. Exogenous expression of Bach1 inhibited the cell proliferation and the expression of cyclin D1, induced an S-phase arrest, and increased the expression of cyclin E2, which were partially blocked by NAC. Taken together, our results suggest that Bach1 suppresses cell proliferation and induces cell-cycle arrest and apoptosis by increasing mitochondrial ROS production, suggesting that Bach1 may be a promising treatment target for the treatment of vascular diseases. PMID:27057283

  14. Prevention of hyperglycemia-induced myocardial apoptosis by gene silencing of Toll-like receptor-4

    Singh Manpreet

    2010-12-01

    Full Text Available Abstract Background Apoptosis is an early event involved in cardiomyopathy associated with diabetes mellitus. Toll-like receptor (TLR signaling triggers cell apoptosis through multiple mechanisms. Up-regulation of TLR4 expression has been shown in diabetic mice. This study aimed to delineate the role of TLR4 in myocardial apoptosis, and to block this process through gene silencing of TLR4 in the myocardia of diabetic mice. Methods Diabetes was induced in C57/BL6 mice by the injection of streptozotocin. Diabetic mice were treated with 50 μg of TLR4 siRNA or scrambled siRNA as control. Myocardial apoptosis was determined by TUNEL assay. Results After 7 days of hyperglycemia, the level of TLR4 mRNA in myocardial tissue was significantly elevated. Treatment of TLR4 siRNA knocked down gene expression as well as diminished its elevation in diabetic mice. Apoptosis was evident in cardiac tissues of diabetic mice as detected by a TUNEL assay. In contrast, treatment with TLR4 siRNA minimized apoptosis in myocardial tissues. Mechanistically, caspase-3 activation was significantly inhibited in mice that were treated with TLR4 siRNA, but not in mice treated with control siRNA. Additionally, gene silencing of TLR4 resulted in suppression of apoptotic cascades, such as Fas and caspase-3 gene expression. TLR4 deficiency resulted in inhibition of reactive oxygen species (ROS production and NADPH oxidase activity, suggesting suppression of hyperglycemia-induced apoptosis by TLR4 is associated with attenuation of oxidative stress to the cardiomyocytes. Conclusions In summary, we present novel evidence that TLR4 plays a critical role in cardiac apoptosis. This is the first demonstration of the prevention of cardiac apoptosis in diabetic mice through silencing of the TLR4 gene.

  15. Generation of reactive oxygen species by a novel berberine–bile acid analog mediates apoptosis in hepatocarcinoma SMMC-7721 cells

    Graphical abstract: - Highlights: • Anticancer effects of B4, a novel berberine–bile acid analog, were tested. • B4 inhibited cell proliferation in hepatocellular carcinoma cells. • It also stimulated mitochondrial ROS production and membrane depolarization. • Effects of B4 were inhibited by a non-specific ROS scavenger. • Regulation of ROS generation may be a strategy for treating hepatic carcinoma. - Abstract: 2,3-Methenedioxy-9-O-(3′α,7′α-dihydroxy-5′β-cholan-24′-propy-lester) berberine (B4) is a novel berberine–bile acid analog synthesized in our laboratory. Previously, we showed that B4 exerted greater cytotoxicity than berberine in several human cancer cell lines. Therefore, we further evaluated the mechanism governing its anticancer actions in hepatocellular carcinoma SMMC-7721 cells. B4 inhibited the proliferation of SMMC-7721 cells, and stimulated reactive oxygen species (ROS) production and mitochondrial membrane depolarization; anti-oxidant capacity was reduced. B4 also induced the release of cytochrome c from the mitochondria to the cytosol and an increase in poly ADP-ribose polymerase (PARP) cleavage products, reflective of caspase-3 activation. Moreover, B4 induced the nuclear translocation of apoptosis-inducing factor (AIF) and a rise in DNA fragmentation. Pretreatment with the anti-oxidant N-acetylcysteine (NAC) inhibited B4-mediated effects, including cytotoxicity, ROS production, mitochondrial membrane depolarization increase in intracellular Ca2+, cytochrome c release, PARP cleavage, and AIF translocation. Our data suggest that B4 induces ROS-triggered caspase-dependent and caspase-independent apoptosis pathways in SMMC-7721 cells and that ROS production may be a specific potential strategy for treating hepatic carcinoma

  16. Generation of reactive oxygen species by a novel berberine–bile acid analog mediates apoptosis in hepatocarcinoma SMMC-7721 cells

    Li, Qingyong, E-mail: li_qingyong@126.com [Key Laboratory of Forest Plant Ecology (Northeast Forestry University), Ministry of Education (China); Zhang, Li; Zu, Yuangang; Liu, Tianyu; Zhang, Baoyou; He, Wuna [Key Laboratory of Forest Plant Ecology (Northeast Forestry University), Ministry of Education (China)

    2013-04-19

    Graphical abstract: - Highlights: • Anticancer effects of B4, a novel berberine–bile acid analog, were tested. • B4 inhibited cell proliferation in hepatocellular carcinoma cells. • It also stimulated mitochondrial ROS production and membrane depolarization. • Effects of B4 were inhibited by a non-specific ROS scavenger. • Regulation of ROS generation may be a strategy for treating hepatic carcinoma. - Abstract: 2,3-Methenedioxy-9-O-(3′α,7′α-dihydroxy-5′β-cholan-24′-propy-lester) berberine (B4) is a novel berberine–bile acid analog synthesized in our laboratory. Previously, we showed that B4 exerted greater cytotoxicity than berberine in several human cancer cell lines. Therefore, we further evaluated the mechanism governing its anticancer actions in hepatocellular carcinoma SMMC-7721 cells. B4 inhibited the proliferation of SMMC-7721 cells, and stimulated reactive oxygen species (ROS) production and mitochondrial membrane depolarization; anti-oxidant capacity was reduced. B4 also induced the release of cytochrome c from the mitochondria to the cytosol and an increase in poly ADP-ribose polymerase (PARP) cleavage products, reflective of caspase-3 activation. Moreover, B4 induced the nuclear translocation of apoptosis-inducing factor (AIF) and a rise in DNA fragmentation. Pretreatment with the anti-oxidant N-acetylcysteine (NAC) inhibited B4-mediated effects, including cytotoxicity, ROS production, mitochondrial membrane depolarization increase in intracellular Ca{sup 2+}, cytochrome c release, PARP cleavage, and AIF translocation. Our data suggest that B4 induces ROS-triggered caspase-dependent and caspase-independent apoptosis pathways in SMMC-7721 cells and that ROS production may be a specific potential strategy for treating hepatic carcinoma.

  17. HIV-1 Vpr-induced cell death in Schizosaccharomyces pombe is reminiscent of apoptosis

    Sylvain Huard; Mingzhong Chen; Kristen E Burdette; Csaba Fenyvuesvolgyi; Min Yu; Robert T Elder; Richard Y Zhao

    2008-01-01

    Human immunodeficiency virus type 1 (HIV-1) Vpr induces cell death in mammalian and fission yeast cells,suggesting that Vpr may affect a conserved cellular process. It is unclear,however,whether Vpr-induced yeast cell death mimics Vpr-mediated apoptosis in mammalian cells. We have recently identified a number of Vpr suppressors that not only suppress Vpr-induced cell death in fission yeast,but also block Vpr-induced apoptosis in mammalian cells. These findings suggest that Vpr-induced cell death in yeast may resemble some of the apoptotic processes of mammalian cells.The goal of this study was to develop and validate a fission yeast model system for future studies of apoptosis. Similar to Vpr-induced apoptosis in mammalian cells,we show here that Vpr in fission yeast promotes phosphatidylserine externalization and induces hyperpolarization of mitochondria,leading to changes of mitochondrial membrane potential. Moreover,Vpr triggers production of reactive oxygen species (ROS),indicating that the apoptotic-like cell death might be mediated by ROS. Interestingly,Vpr induces unique morphologic changes in mitochondria that may provide a simple marker for measuring the apoptotic-like process in fission yeast. To verify this possibility,we tested two Vpr suppressors (EF2 and Hspl6) that suppress Vpr-induced apoptosis in mammalian cells in addition to a newly identified Vpr suppressor (Skp1). All three proteins abolished cell death mediated by Vpr and restored normal mitochondrialmorphology in the yeast cells. In conclusion,Vpr-induced cell death in fission yeast resembles the mammalian apoptotic process. Fission yeast may thus potentially be used as a simple model organism for the future study of the apoptotic-like process induced by Vpr and other proapoptotic agents.

  18. Oridonin phosphate-induced autophagy effectively enhances cell apoptosis of human breast cancer cells.

    Li, Yue; Wang, Ying; Wang, Suihai; Gao, Yanjun; Zhang, Xuefeng; Lu, Chunhua

    2015-01-01

    Oridonin is an active diterpenoid, which was extracted from traditional Chinese herbs and had been widely used in clinical treatment nowadays. Oridonin phosphate is one of the derivatives of oridonin. In the present study, we explored its anti-tumor effect and investigated the molecular mechanism of oridonin phosphate in breast cancer cell lines. Firstly, cell viability was analyzed by MTT assay. The breast cancer cells were treated with increasing concentrations of oridonin phosphate for 24, 48 and 72 h, respectively. The results demonstrated that oridonin phosphate inhibited the proliferation of MDA-MB-436 and MDA-MB-231 cells in a dose- and time-dependent manner. Next, cell apoptosis rate was detected in oridonin phosphate-treated breast cancer cells by Annexin V-FITC/PI dual staining analysis and the data demonstrated that oridonin phosphate induced cell apoptosis of breast cancer cells in time- and dose-dependent manner. Moreover, apoptosis-related proteins were detected by Western blotting analysis. The results showed that the expression level of Bax was up-regulated and the expression level of Bcl-2 was down-regulated. Meanwhile, the level of cleaved caspase-9 was significantly increased when the cells were treated with 40 μM of oridonin phosphate for 48 h, although the expression level of pro-caspase-9 was not obviously changed. All of the data revealed that mitochondrial apoptosis pathway may be involved in the cell apoptosis induced by oridonin phosphate in breast cancer cells. Importantly, the expression levels of autophagy-related protein beclin-1 and LC3-II were significantly higher in oridonin phosphate-treated breast cancer cell lines MDA-MB-436 and MDA-MB-231 for 48 h. Additionally, we further explored the relationship between apoptosis and autophagy specifically induced by oridonin phosphate in breast cancer cells. The result showed that inhibition of autophagy suppressed the cell apoptosis in oridonin phosphate-treated MDA-MB-436 cells. Taken

  19. Noscapine induces mitochondria-mediated apoptosis in human colon cancer cells in vivo and in vitro

    Yang, Zi-Rong; Liu, Meng; Peng, Xiu-Lan; Lei, Xiao-Fei; Zhang, Ji-Xiang [Department of Gastroenterology, Renmin Hospital of Wuhan University, Wuhan 430060, Hubei Province (China); Dong, Wei-Guo, E-mail: dongwg1966@yahoo.com.cn [Department of Gastroenterology, Renmin Hospital of Wuhan University, Wuhan 430060, Hubei Province (China)

    2012-05-11

    Highlights: Black-Right-Pointing-Pointer Noscapine inhibited cell viability of colon cancer in a time- and dose- dependent manner. Black-Right-Pointing-Pointer G{sub 2}/M phase arrest and chromatin condensation and nuclear fragmentation were induced. Black-Right-Pointing-Pointer Noscapine promoted apoptosis via mitochondrial pathways. Black-Right-Pointing-Pointer Tumorigenicity was inhibited by noscapine. -- Abstract: Noscapine, a phthalide isoquinoline alkaloid derived from opium, has been widely used as a cough suppressant for decades. Noscapine has recently been shown to potentiate the anti-cancer effects of several therapies by inducing apoptosis in various malignant cells without any detectable toxicity in cells or tissues. However, the mechanism by which noscapine induces apoptosis in colon cancer cells remains unclear. The signaling pathways by which noscapine induces apoptosis were investigated in colon cancer cell lines treated with various noscapine concentrations for 72 h, and a dose-dependent inhibition of cell viability was observed. Noscapine effectively inhibited the proliferation of LoVo cells in vitro (IC{sub 50} = 75 {mu}M). This cytotoxicity was reflected by cell cycle arrest at G{sub 2}/M and subsequent apoptosis, as indicated by increased chromatin condensation and fragmentation, the upregulation of Bax and cytochrome c (Cyt-c), the downregulation of survivin and Bcl-2, and the activation of caspase-3 and caspase-9. Moreover, in a xenograft tumor model in mice, noscapine injection clearly inhibited tumor growth via the induction of apoptosis, which was demonstrated using a TUNEL assay. These results suggest that noscapine induces apoptosis in colon cancer cells via mitochondrial pathways. Noscapine may be a safe and effective chemotherapeutic agent for the treatment of human colon cancer.

  20. P53 dependent and independent apoptosis induced by lidamycin in human colorectal cancer cells.

    Chen, Lihui; Jiang, Jianming; Cheng, Chunlei; Yang, Ajing; He, Qiyang; Li, Diandong; Wang, Zhen

    2007-06-01

    Enediyne compound is one class of antibiotics with very potent anti-cancer activity. However, the role of p53 in enediyne antibiotic-induced cell killing remains elusive. Here we reported the involvement of p53 signaling pathway in apoptosis induction by lidamycin (LDM), a member of the enediyne antibiotic family. We found that LDM at low drug concentration of 10 nmol/L induces apoptotic cell death much more effectively in human colorectal cancer cells with wild type p53 than those with mutant or deleted p53. p53 is functionally activated as an early event in response to low dose LDM that precedes the significant apoptosis induction. The primarily activation of mitochondria as well as the activation of p53 transcriptional targets such as Puma, Bad and Bax in HCT116 p53 wild type cells further demonstrates the key role of p53 in mediating the compound-induced apoptosis. This is further supported by the observation that the absence of Bax or Puma decreases apoptosis dramatically while Bcl-2 overexpression confers partially resistance after drug treatment. Activation of p53 signaling pathway leads to activation of caspases and caspases inhibitor VAD-fmk completely blocks low dose LDM induced apoptosis through the inhibition of mitochondria pathway. In contrast, LDM at higher concentration causes rapid apoptosis through more direct DNA damaging mechanism that is independent of activation of p53 and caspases and cannot be blocked by caspase inhibitor. Taken together, LDM induces apoptosis in a p53-dependent manner when given at low doses, but in a p53-independent manner when given at high doses. This dosage-dependent regimen can be applied to cancer clinic based upon the p53 status of cancer patients. PMID:17534142

  1. Noscapine induces mitochondria-mediated apoptosis in human colon cancer cells in vivo and in vitro

    Highlights: ► Noscapine inhibited cell viability of colon cancer in a time- and dose- dependent manner. ► G2/M phase arrest and chromatin condensation and nuclear fragmentation were induced. ► Noscapine promoted apoptosis via mitochondrial pathways. ► Tumorigenicity was inhibited by noscapine. -- Abstract: Noscapine, a phthalide isoquinoline alkaloid derived from opium, has been widely used as a cough suppressant for decades. Noscapine has recently been shown to potentiate the anti-cancer effects of several therapies by inducing apoptosis in various malignant cells without any detectable toxicity in cells or tissues. However, the mechanism by which noscapine induces apoptosis in colon cancer cells remains unclear. The signaling pathways by which noscapine induces apoptosis were investigated in colon cancer cell lines treated with various noscapine concentrations for 72 h, and a dose-dependent inhibition of cell viability was observed. Noscapine effectively inhibited the proliferation of LoVo cells in vitro (IC50 = 75 μM). This cytotoxicity was reflected by cell cycle arrest at G2/M and subsequent apoptosis, as indicated by increased chromatin condensation and fragmentation, the upregulation of Bax and cytochrome c (Cyt-c), the downregulation of survivin and Bcl-2, and the activation of caspase-3 and caspase-9. Moreover, in a xenograft tumor model in mice, noscapine injection clearly inhibited tumor growth via the induction of apoptosis, which was demonstrated using a TUNEL assay. These results suggest that noscapine induces apoptosis in colon cancer cells via mitochondrial pathways. Noscapine may be a safe and effective chemotherapeutic agent for the treatment of human colon cancer.

  2. Astragaloside IV prevents high glucose-induced podocyte apoptosis via downregulation of TRPC6.

    Yao, Xing-Mei; Liu, Yu-Jun; Wang, Yun-Man; Wang, Hao; Zhu, Bing-Bing; Liang, Yong-Ping; Yao, Wei-Guo; Yu, Hui; Wang, Nian-Song; Zhang, Xue-Mei; Peng, Wen

    2016-06-01

    Diabetic nephropathy (DN) is one of the most important causes of end‑stage renal disease. Astragaloside IV (AS-IV) is a saponin isolated from Astragalus membranaceus, which possesses various pharmacological activities. AS‑IV prevents podocyte apoptosis and ameliorates renal injury in DN; however, few studies have focused on its effects on ion channels. The transient receptor potential channel 6 (TRPC6) is an important Ca2+‑permeable ion channel in podocytes, which is involved in high glucose (HG)-induced podocyte apoptosis. The aim of the present study was to investigate whether AS‑IV prevented HG‑induced podocyte apoptosis via TRPC6. Cultured podocytes were pre‑treated with 10, 20 or 40 µM AS‑IV for 1 h prior to HG exposure for 24 h. Apoptosis, cell viability, expression of TRPC6, nuclear factor of activated T cells (NFAT2) and B‑cell lymphoma 2‑associated X protein (Bax), as well as the intracellular Ca2+ concentration were subsequently analyzed. The results indicated that HG induced podocyte apoptosis and upregulation of TRPC6, and increased intracellular Ca2+. Furthermore, enhanced NFAT2 and Bax expression was detected. Conversely, AS‑IV protected HG‑induced podocyte apoptosis, downregulated TRPC6 expression and suppressed intracellular Ca2+ in HG-stimulated podocytes. AS‑IV also suppressed NFAT2 and Bax expression. These results suggest that AS‑IV may prevent HG-induced podocyte apoptosis via downregulation of TRPC6, which is possibly mediated via the calcineurin/NFAT signaling pathway. PMID:27109610

  3. Effects of cerebrolysin administration on oxidative stress-induced apoptosis in lymphocytes from CADASIL patients.

    Formichi, Patrizia; Radi, Elena; Battisti, Carla; Di Maio, Giuseppe; Dotti, Maria Teresa; Muresanu, Dafin; Federico, Antonio

    2013-04-01

    Cerebrolysin (Cere) is a peptidergic nootropic drug with neurotrophic properties which has been used to treat dementia and sequelae of stroke. Use of Cere prevents nuclear structural changes typical of apoptosis and significantly reduces the number of apoptotic cells after several apoptotic stimuli. Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy (CADASIL) is a hereditary disease caused by mutations of the Notch3 gene encoding the Notch3 protein. Notch3 is involved in the regulation of apoptosis, modulating Fas-Ligand (Fas-L)- induced apoptosis. The aim of this study was to evaluate the in vitro protective effects of Cere against oxidative stress-induced apoptosis in cells from CADASIL patients. We used peripheral blood lymphocytes (PBLs) from 15 CADASIL patients (age range 34-70 years); 2-deoxy-D-ribose (dRib), a highly reducing sugar, was used as paradigm pro-apoptotic stimulus. Apoptosis was analyzed by flow cytometry and fluorescence microscopy. Administration of Cere to PBLs from CADASIL patients cultured under standard conditions had no effect on the percentage of apoptotic cells. Administration of Cere to PBLs cultured with dRib caused a significant decrease in apoptosis after 48 h of culture in only 5 patients, whereas in the other 10 patients, Cere treatment was not associated with any significant difference in the percentage of apoptosis. This result showed a protective effect of Cere against oxidative stress-induced apoptosis only in 30 % of the CADASIL patients, suggesting that the Notch3 gene probably does not influence the anti-apoptotic properties of Cere in vitro. PMID:22878905

  4. The vitronectin RGD motif regulates TGF-β-induced alveolar epithelial cell apoptosis.

    Wheaton, Amanda K; Velikoff, Miranda; Agarwal, Manisha; Loo, Tiffany T; Horowitz, Jeffrey C; Sisson, Thomas H; Kim, Kevin K

    2016-06-01

    Transforming growth factor-β (TGF-β) is a critical driver of acute lung injury and fibrosis. Injury leads to activation of TGF-β, which regulates changes in the cellular and matrix makeup of the lung during the repair and fibrosis phase. TGF-β can also initiate alveolar epithelial cell (AEC) apoptosis. Injury leads to destruction of the laminin-rich basement membrane, which is replaced by a provisional matrix composed of arginine-glycine-aspartate (RGD) motif-containing plasma matrix proteins, including vitronectin and fibronectin. To determine the role of specific matrix proteins on TGF-β-induced apoptosis, we studied primary AECs cultured on different matrix conditions and utilized mice with deletion of vitronectin (Vtn(-/-)) or mice in which the vitronectin RGD motif is mutated to nonintegrin-binding arginine-glycine-glutamate (RGE) (Vtn(RGE/RGE)). We found that AECs cultured on fibronectin and vitronectin or in wild-type mouse serum are resistant to TGF-β-induced apoptosis. In contrast, AECs cultured on laminin or in serum from Vtn(-/-) or Vtn(RGE/RGE) mice undergo robust TGF-β-induced apoptosis. Plasminogen activator inhibitor-1 (PAI-1) sensitizes AECs to greater apoptosis by disrupting AEC engagement to vitronectin. Inhibition of integrin-associated signaling proteins augments AEC apoptosis. Mice with transgenic deletion of PAI-1 have less apoptosis after bleomycin, but deletion of vitronectin or disruption of the vitronectin RGD motif reverses this protection, suggesting that the proapoptotic function of PAI-1 is mediated through vitronectin inhibition. Collectively, these data suggest that integrin-matrix signaling is an important regulator of TGF-β-mediated AEC apoptosis and that PAI-1 functions as a natural regulator of this interaction. PMID:27106291

  5. Iodinated contrast media induce neutrophil apoptosis through a mitochondrial and caspase mediated pathway.

    Fanning, N F

    2012-02-03

    Iodinated contrast media (ICM) can induce apoptosis (programmed cell death) in renal, myocardial and endothelial cells. Following intravascular injection, circulating immune cells are exposed to high concentrations of ICM. As neutrophils constitutively undergo apoptosis we hypothesized that ICM may adversely affect neutrophil survival. Our aim was to investigate the effect of ICM on neutrophil apoptosis. Neutrophils were isolated from healthy subjects and cultured in vitro with ionic (diatrizoate and ioxaglate) and non-ionic (iohexol and iotrolan) ICM. The effect of ICM on neutrophil apoptosis in both unstimulated and lipopolysaccharide-stimulated neutrophils was determined by annexin V flow cytometry. The influence of physicochemical properties of the different ICM on apoptosis of neutrophils was also studied. We further investigated the effects of ICM on key intracellular signal pathways, including p38 mitogen-activated protein kinase (MAPK) by Western blotting, and mitochondrial depolarization and caspase activity by flow cytometry. Isoiodine concentrations (20 mg ml(-1)) of ionic (diatrizoate 69.6+\\/-2.9%; ioxaglate 58.9+\\/-2.0%) and non-ionic (iohexol 57.3+\\/-2.9%; iotrolan 57.1+\\/-2.6%) ICM significantly induced neutrophil apoptosis over control levels (47.7+\\/-1.4%). The apoptotic effect of ICM was influenced by their chemical structure, with ionic ICM having a more significant (p<0.01) apoptotic effect than non-ionic ICM (p<0.05). Furthermore, ICM reversed the anti-apoptotic effect of lipopolysaccharide (1000 ng ml(-1)) treated neutrophils to control levels (23.0+\\/-3.5% to 61.2+\\/-5.3%; n=4; p<0.05). These agents induce apoptosis through a p38 MAPK independent pathway that results in mitochondrial depolarization, and is dependent on caspase activation. As neutrophils play a central role in host response to infection and injury, ICM, through induction of neutrophil apoptosis, could have a significant deleterious effect on host immune defence and

  6. Protection of rat primary hepatocytes from radiation-induced apoptosis by hepatocyte growth factor (HGF)

    Purpose: Radiation hepatopathy can be a life-threatening treatment complication limiting the therapeutic intervention of irradiation in upper abdominal malignancies. Understanding the mechanisms of radiation-induced liver injury will help us develop methods for the prevention and treatment of this complication. Both liver endothelial cell and hepatocyte injury contribute to the development of radiation hepatopathy. The objective of the present study is to examine the effects of irradiation on primary hepatocyte injury and to investigate how the irradiation effect is modified by the presence of non-parenchymal cells and hepato trophic growth factors such as HGF. Methods: Primary hepatocytes and liver non parenchymal cells were isolated from collagenase perfused Fischer 344 rat livers by a two-step percoll gradient centrifugation. Hepatocytes (>90% viable by Trypan blue exclusion) were cultured in modified Chee medium on collagen-coated Nunc Permanox plates. HGF was added at a concentration of 100 ng/ml. Survival of hepatocytes was determined after 30Gy of Co60 irradiation by Trypan blue dye exclusion and counting Hoechst-33258 stained apoptotic nuclei by fluro scent microscopy. Results: After irradiation, primary hepatocytes exhibited apoptosis which was observed at 6 hours, peaked at 24 hrs and continued up to 72 hours (the last time point in this study). A dose of 30 Gy induced apoptosis in 10-15% of hepatocytes, while unirradiated controls showed >3.0% of apoptotic cells. HGF (100ng/ml) could inhibit the induction of apoptosis in irradiated hepatocytes by 75-80% to the basal level of spontaneous apoptosis, present in unirradiated controls. Daily supplementation of HGF maintained this inhibition of apoptosis for the entire observation period (72 hours). Co incubation of non parenchymal liver cells sensitized hepatocytes to the irradiation-induced apoptosis by three fold. Conclusion: Cultured primary rat hepatocytes undergo apoptosis following irradiation. The rate

  7. Roscovitine sensitizes leukemia and lymphoma cells to tumor necrosis factor-related apoptosis-inducing ligand-induced apoptosis

    Molinsky, J.; Klánová, M.; Koc, Michal; Beranová, Lenka; Anděra, Ladislav; Ludvíková, Z.; Bohmova, M.; Gasova, Z.; Strnad, Miroslav; Ivánek, R.; Trněný, M.; Nečas, E.; Živný, J.; Klener, P.

    2013-01-01

    Roč. 54, č. 2 (2013), s. 372-380. ISSN 1042-8194 R&D Projects: GA MZd NS10287 Institutional research plan: CEZ:AV0Z50380511 Institutional support: RVO:68378050 Keywords : roscovitine * TRAIL * synergism * apoptosis * leukemia * lymphoma Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.605, year: 2013

  8. Apigenin-induced apoptosis is enhanced by inhibition of autophagy formation in HCT116 human colon cancer cells.

    Lee, Yujin; Sung, Bokyung; Kang, Yong Jung; Kim, Dong Hwan; Jang, Jung-Yoon; Hwang, Seong Yeon; Kim, Minjung; Lim, Hyun Sook; Yoon, Jeong-Hyun; Chung, Hae Young; Kim, Nam Deuk

    2014-05-01

    Apigenin (4',5,7-trihydroxyflavone) is a natural flavonoid, shown to have chemopreventive and/or anticancer properties in a variety of human cancer cells. The involvement of autophagy in apigenin-induced apoptotic cell death of HCT116 human colon cancer cells was investigated. Apigenin induced suppression of cell growth in a concentration-dependent manner in HCT116 cells. Flow cytometric analyses indicated that apigenin resulted in G2/M phase arrest. This flavone also suppressed the expression of both cyclin B1 and its activating partners, Cdc2 and Cdc25c, whereas the expression of cell cycle inhibitors, such as p53 and p53-dependent p21(CIP1/WAF1), was increased after apigenin treatment. Apigenin induced poly (ADP-ribose) polymerase (PARP) cleavage and decreased the levels of procaspase-8, -9 and -3. In addition, the apigenin-treated cells exhibited autophagy, as characterized by the appearance of autophagosomes under fluorescence microscopy and the accumulation of acidic vesicular organelles by flow cytometry. Furthermore, the results of the western blot analysis revealed that the levels of LC3-II, the processed form of LC3-I, was increased by apigenin. Treatment with the autophagy inhibitor 3-methyladenine (3-MA) significantly enhanced the apoptosis induced by apigenin, which was accompanied by an increase in the levels of PARP cleavage. These results indicate that apigenin has apoptosis- and autophagy-inducing effects in HCT116 colon cancer cells. Autophagy plays a cytoprotective role in apigenin-induced apoptosis, and the combination of apigenin and an autophagy inhibitor may be a promising strategy for colon cancer control. PMID:24626522

  9. Mechanisms of methicillin-resistant Staphylococcus aureus pneumonia-induced intestinal epithelial apoptosis.

    Perrone, Erin E; Jung, Enjae; Breed, Elise; Dominguez, Jessica A; Liang, Zhe; Clark, Andrew T; Dunne, W Michael; Burd, Eileen M; Coopersmith, Craig M

    2012-07-01

    Methicillin-resistant Staphylococcus aureus (MRSA) pneumonia-induced sepsis is a common cause of morbidity in the intensive care unit. Although pneumonia is initiated in the lungs, extrapulmonary manifestations occur commonly. In light of the key role the intestine plays in the pathophysiology of sepsis, we sought to determine whether MRSA pneumonia induces intestinal injury. FVB/N mice were subjected to MRSA or sham pneumonia and killed 24 h later. Septic animals had a marked increase in intestinal epithelial apoptosis by both hematoxylin-eosin and active caspase 3 staining. Methicillin-resistant S. aureus-induced intestinal apoptosis was associated with an increase in the expression of the proapoptotic proteins Bid and Bax and the antiapoptotic protein Bcl-xL in the mitochondrial pathway. In the receptor-mediated pathway, MRSA pneumonia induced an increase in Fas ligand but decreased protein levels of Fas, FADD, pFADD, TNF-R1, and TRADD. To assess the functional significance of these changes, MRSA pneumonia was induced in mice with genetic manipulations in proteins in either the mitochondrial or receptor-mediated pathways. Both Bid-/- mice and animals with intestine-specific overexpression of Bcl-2 had decreased intestinal apoptosis compared with wild-type animals. In contrast, Fas ligand-/- mice had no alterations in apoptosis. To determine if these findings were organism-specific, similar experiments were performed in mice subjected to Pseudomonas aeruginosa pneumonia. Pseudomonas aeruginosa induced gut apoptosis, but unlike MRSA, this was associated with increased Bcl-2 and TNF-R1 and decreased Fas. Methicillin-resistant S. aureus pneumonia thus induces organism-specific changes in intestinal apoptosis via changes in both the mitochondrial and receptor-mediated pathways, although the former may be more functionally significant. PMID:22592747

  10. Involvement of FAN in TNF-induced apoptosis

    Ségui, Bruno; Cuvillier, Olivier; Adam-Klages, Sabine; Garcia, Virginie; Malagarie-Cazenave, Sophie; Lévêque, Sophie; Caspar-Bauguil, Sylvie; Coudert, Jérôme,; Salvayre, Robert; Krönke, Martin; Levade, Thierry

    2001-01-01

    TNF-α is a pleiotropic cytokine activating several signaling pathways initiated at distinct intracellular domains of the TNF receptors. Although the C-terminal region is believed to be responsible for apoptosis induction, the functions of more membrane-proximal domains, including the domain that couples to neutral sphingomyelinase activation, are not yet fully elucidated. The roles of this region and of the associated adapter protein FAN (factor associated with neutral SMase activation) in th...

  11. Osteoprotegerin Prevents Glucocorticoid-Induced Osteocyte Apoptosis in Mice

    Weinstein, Robert S; O'Brien, Charles A; Almeida, Maria; Zhao, Haibo; Roberson, Paula K.; Jilka, Robert L.; Manolagas, Stavros C.

    2011-01-01

    The adverse skeletal effects of glucocorticoid excess are due to increased osteoclast survival, decreased production of osteoblasts, and increased apoptosis of osteoblasts and osteocytes, but it remains unknown which of these is the principle cause of the decrease in bone strength. Previous studies suggested that osteocytes contribute to bone strength independently of changes in bone mass. Administration of the receptor activator for nuclear factor κB ligand (RANKL) antagonist osteoprotegerin...

  12. Effect of fucoidan on splenic lymphocyte apoptosis induced by radiation

    Objective: To investigate the effect of immunologic function of fucoidan at different doses given preventively to rats exposed to γ-rays and its mechanism. Methods: The Wistar rats were given fucoidan at different doses orally for 10 d before whole-body irradiation with 60Co γ-rays. The related indexes of humoral, cellular and nonspecific immunologic functions and apoptosis ratio of lymphocytes were measured 18 hs later. Results: Fucoidan at 100 mg/kg was able to significantly enhance the ability of proliferation responses of T, B lymphocytes, the number and phagocytosis of macrophage, serum hemolysin contents, the delayed type hypersensitivity response (DTH) of rats exposed to γ-rays and to reduce apoptosis ratio of lymphocytes in irradiated rats. There were dose-effect relationships in these observation indexes of the fucoidan groups. There were significant differences between these indexes of the fucoidan groups and those of the positive control group (P<0.01). Conclusion: These results indicate that fucoidan as an immunoregulatory chemical could promote the recovery of immunologic function in irradiated rats. The mechanism is associated with the arrest of lymphocyte apoptosis by fucoidan

  13. Roles of Fas signaling pathway in vitamin E succinate-induced apoptosis in human gastric cancer SGC-7901 cells

    Kun Wu; Yao Li; Yan Zhao; Yu-Juan Shan; Wei Xia; Wei-Ping Yu; Lan Zhao

    2002-01-01

    AIM: To investigate the roles of Fas signaling pathway in vitamin E succinate-induced apoptosis in human gastric cancer SGC-7901 cells.METHODS: Human gastric cancer SGC-7901 cells were treated with VES at 5, 10, 20 mg@L-1, succinic acid and vitamin E as vehicle control and condition media only as untreated (UT) control. Apoptotic morphology was observed by DAPI staining. Western blot analysis was applied to measure the expression of Fas, FADD and caspase-8 proteins. After the cells were transiently transfected with Fas and FADD antisense oligonucleotides, respectively, caspase-8 activity was determined by flurometric method.RESULTS: The morphologically apoptotic changes were observed after VES treatment by DAPI staining. 23.7 % and 89.6 % apoptosis occurred after 24 h and 48 h of 20 mg@L-1 VES treatment, respectively. The protein levels of Fas, FADD and caspase-8 were evidently increased in a dose-dependent manner after 24 h of VES treatment. The blockage of Fas by transfection with Fas antisense oligonucleotides obviously inhibited the expression of FADD protein. After SGC-7901 cells were transfected with Fas and FADD antisense oligonucleotides, caspase-8 activity was obviously decreased (P<0.01), whereas Fas blocked more than FADD.CONCLUSION: VES-induced apoptosis in human gastric cancer SGC-7901 cells involves Fas signaling pathway including the interaction of Fas, FADD and caspase-8.

  14. Protein phosphatase 1α is a Ras-activated Bad phosphatase that regulates interleukin-2 deprivation-induced apoptosis

    Ayllón, Verónica; Martínez-A, Carlos; García, Alphonse; Cayla, Xavier; Rebollo, Angelita

    2000-01-01

    Growth factor deprivation is a physiological mechanism to regulate cell death. We utilize an interleukin-2 (IL-2)-dependent murine T-cell line to identify proteins that interact with Bad upon IL-2 stimulation or deprivation. Using the yeast two-hybrid system, glutathione S-transferase (GST) fusion proteins and co-immunoprecipitation techniques, we found that Bad interacts with protein phosphatase 1α (PP1α). Serine phosphorylation of Bad is induced by IL-2 and its dephosphorylation correlates with appearance of apoptosis. IL-2 deprivation induces Bad dephosphorylation, suggesting the involvement of a serine phosphatase. A serine/threonine phosphatase activity, sensitive to the phosphatase inhibitor okadaic acid, was detected in Bad immunoprecipitates from IL-2-stimulated cells, increasing after IL-2 deprivation. This enzymatic activity also dephosphorylates in vivo 32P-labeled Bad. Treatment of cells with okadaic acid blocks Bad dephosphorylation and prevents cell death. Finally, Ras activation controls the catalytic activity of PP1α. These results strongly suggest that Bad is an in vitro and in vivo substrate for PP1α phosphatase and that IL-2 deprivation-induced apoptosis may operate by regulating Bad phosphorylation through PP1α phosphatase, whose enzymatic activity is regulated by Ras. PMID:10811615

  15. Role of Signal Regulatory Protein α in Arsenic Trioxide-induced Promyelocytic Leukemia Cell Apoptosis.

    Pan, Chaoyun; Zhu, Dihan; Zhuo, Jianjiang; Li, Limin; Wang, Dong; Zhang, Chen-Yu; Liu, Yuan; Zen, Ke

    2016-01-01

    Signal regulatory protein α (SIRPα) has been shown to operate as a negative regulator in cancer cell survival. The mechanism underneath such function, however, remains poorly defined. In the present study, we demonstrate that overexpression of SIRPα in acute promyelocytic leukemia (APL) cells results in apoptosis possibly via inhibiting the β-catenin signaling pathway and upregulating Foxo3a. Pharmacological activation of β-catenin signal pathway attenuates apoptosis caused by SIRPα. Interestingly, we also find that the pro-apoptotic effect of SIRPα plays an important role in arsenic trioxide (ATO)-induced apoptosis in APL cells. ATO treatment induces the SIRPα protein expression in APL cells and abrogation of SIRPα induction by lentivirus-mediated SIRPα shRNA significantly reduces the ATO-induced apoptosis. Mechanistic study further shows that induction of SIRPα protein in APL cells by ATO is mediated through suppression of c-Myc, resulting in reduction of three SIRPα-targeting microRNAs: miR-17, miR-20a and miR-106a. In summary, our results demonstrate that SIRPα inhibits tumor cell survival and significantly contributes to ATO-induced APL cell apoptosis. PMID:27010069

  16. Honokiol induces apoptosis through p53-independent pathway in human colorectal cell line RKO

    Tao Wang; Fei Chen; Zhe Chen; Yi-Feng Wu; Xiao-Li Xu; Shu Zheng; Xun Hu

    2004-01-01

    AIM: To investigate the signal pathway of honokiol-induced apoptosis on human colorectal carcinoma RKO cells and to evaluate whether p53 and p53-related genes were involved in honokiol-treated RKO cells.METHODS: Cell cycle distribution and subdiploid peak were analyzed with a flow cytometer and DNA fragment with electrophoresis on agarose gels. Transcriptional level of Bax, Bcl-2, Bid and Bcl-xl was accessed by RT-PCR.Western blotting was used to measure p53 protein expression and other factors related to apoptosis.Proliferation inhibition of two cell lines (RKO, SW480) with high expression of p53 and one cell line with p53 negative expression (LS180) was monitored by MTT assay.RESULTS: Honokiol induced RKO cell apoptosis in a dosedependent manner. The mRNA expression level and protein level of Bid were up-regulated while that of Bcl-xl was down-regulated, but no changes in Bax and Bcl-2 were observed. Western blotting showed p53 expression had no remarkable changes in honokiol-induced RKO cell apoptosis. LS180 cells treated with honokiol exhibited apparent growth inhibition like RKO cells and Sw480 cells.CONCLUSION: Honokiol can induce RKO cells apoptosis through activating caspase cascade by p53-indepenent pathway.

  17. Hydrogen sulfide prevents Abeta-induced neuronal apoptosis by attenuating mitochondrial translocation of PTEN.

    Cui, Weigang; Zhang, Yinghua; Yang, Chenxi; Sun, Yiyuan; Zhang, Min; Wang, Songtao

    2016-06-14

    Neuronal cell apoptosis is an important pathological change in Alzheimer's disease (AD). Hydrogen sulfide (H(2)S) is known to be a novel gaseous signaling molecule and a cytoprotectant in many diseases including AD. However, the molecular mechanism of the antiapoptosis activity of H(2)S in AD is not yet fully understood. The aim of the present study is to evaluate the inhibitory effects of H(2)S on Abeta (Aβ)-induced apoptosis and the molecular mechanisms underlying primary neuron cells. Our results showed that sodium hydrosulfide (NaHS), a donor of H(2)S, significantly ameliorated Aβ-induced cell apoptosis. NaHS also reversed the Aβ-induced translocation of the phosphatase and tensin homologs deleted on chromosome 10 (PTEN) from the cytosol to the mitochondria. Furthermore, H(2)S increased the level of p-AKT/AKT significantly. Interestingly, the antiapoptosis effects of H(2)S were blocked down by specific PI3K/AKT inhibitor wortmannin. In conclusion, these data indicate that H(2)S inhibits Aβ-induced neuronal apoptosis by attenuating mitochondrial translocation of PTEN and that activation of PI3K/AKT signaling pathway plays a critical role in H(2)S-mediated neuronal protection. Our findings provide a novel route into the molecular mechanisms of neuronal apoptosis in AD. PMID:27026591

  18. Zinc inhibits ethanol-induced HepG2 cell apoptosis

    Alcohol consumption produces a variety of metabolic alterations in liver cells, associated with ethanol oxidation and with nonoxidative metabolism of ethanol, among others apoptosis of hepatocytes. As zinc is known as a potent antioxidant and an inhibitor of cell apoptosis, the aim of this paper was to investigate whether zinc supplementation could inhibit ethanol-induced HepG2 apoptosis, and whether this inhibition was connected with attenuation of oxidative stress and modulation of FasR/FasL system expression. The results indicated that zinc supplementation significantly inhibited ethanol-induced HepG2 cell apoptosis (measured by cytochrome c release from mitochondria and caspase-3 activation) by attenuation of reactive oxygen species (ROS) production, increase in the cellular level of GSH, inhibition of ethanol-induced sFasR and FasL overexpression and caspase-8 activation. These results indicate that zinc can inhibit ethanol-induced hepatocyte apoptosis by several independent mechanisms, among others by an indirect antioxidative effect and probably by inhibition of caspase-8 and caspase-9 activation

  19. Methylanthraquinone from Hedyotis diffusa WILLD induces Ca(2+)-mediated apoptosis in human breast cancer cells.

    Liu, Zheng; Liu, Ming; Liu, Miao; Li, Jianchun

    2010-02-01

    Methylanthraquinone from Hedyotis diffusa WILLD exhibited potent anticancer activity in many kinds of cancer cells. However, the exact mechanism and signaling pathway involved in methylanthraquinone-induced apoptosis have not been fully elucidated. Therefore, we explored the mechanisms of methylanthraquinone-mediated apoptosis in MCF-7 human breast cancer cells. When MCF-7 cells were co-incubated with methylanthraquinone, the percentage of apoptotic cell and S phase of cell cycle was markedly increased. In addition, a rise in intracellular calcium levels, phosphorylation of JNK and activation of calpain were found in MCF-7 cells after exposure to methylanthraquinone. With the methylanthraquinone-mediated reduction of mitochondrial membrane potential, cytochrome c was released from mitochondria to cytosol. Moreover, methylanthraquinone strongly induced cleavage of caspase-4, caspase-9 and caspase-7 in MCF-7 cells. These results suggested that methylanthraquinone from Hedyotis diffusa WILLD induced MCF-7 cells apoptosis via Ca(2+)/calpain/caspase-4 pathway. PMID:19686834

  20. Bax is not involved in the resveratrol-induced apoptosis in human lung adenocarcinoma cells

    Zhang, Wei-wei; Wang, Zhi-ping; Chen, Tong-sheng

    2010-02-01

    Resveratrol (RV) is a natural plant polyphenol widely present in foods such as grapes, wine, and peanuts. Previous studies indicate that RV has an ability to inhibit various stages of carcinogenesis and eliminate preneoplastic cells in vitro and in vivo. However, little is known about the molecular mechanism of RV-induced apoptosis in human lung adenocarcinoma (ASTC-a-1) cell. In this report, we analyzed whether Bax translocation from cytoplasm to mitochondria during RV-induced apoptosis in single living cell using onfocal microscopey. Cells were transfected with GFP-Bax plasmid. Cell counting kit (CCK-8) assay was used to assess the inhibition of RV on the cells viability. Apoptotic activity of RV was detected by Hoechst 33258 and propidium iodide (PI) staining. Our results showed that RV induced a dose-dependent apoptosis in which Bax did not translocate to mitochondrias.

  1. Protective effects of Ginkgo biloba extract on 6-hydroxydopamine-induced apoptosis in PC12 cells

    Jie Wang; Yanbo Cheng; Jiale Yin; Qian Lu; Xingshun Xu; Xiaoxing Yin

    2011-01-01

    The present study analyzed the protective effects of Ginkgo biloba extract against 6-hydroxydopamine-induced PC12 cell apoptosis in a model of Parkinson's disease. The results showed that Ginkgo biloba extract had a potent cytoprotective action and inhibited apoptosis of PC12 cells induced by 6-hydroxydopamine. Ginkgo biloba extract decreased the ratio of Bax to Bcl-2 and markedly inhibited the activation of p53 and caspase-3. These experimental findings indicate that Ginkgo biloba extract may significantly reduce the effects of oxidative stress induced by 6-hydroxydopamine in PC12 cells and suppress cell apoptosis. The potential effects of Ginkgo biloba extract might be greater than those of levodopa in the treatment of Parkinson's disease.

  2. Spatial and temporal changes in Bax subcellular localization during NPe6-PDT-induced apoptosis

    Liu, Lei; Xing, Da; Chen, Wei R.; Wan, Qingling; Zhou, Feifan

    2008-02-01

    Photodynamic therapy (PDT) employing photosensiter N-aspartyl chlorin e6 (NPe6) can induce lysosome disruption and initiate the intrinsic apoptotic pathway. Bax, a member of the Bcl-2 family of proteins, is an essential regulator of apoptosis. Bax is normally found in the cytosol of healthy cells, and translocates to mitochondria in response to many apoptotic stimuli. In this study, using real-time single-cell analysis, we have investigated the kinetics of Bax distribution during NPe6-induced apoptosis in ASTC-a-1 cells. In order to monitor Bax subcellular distribution, cells were stained with GFP-Bax and Mito Tracker Red. The results show that Bax redistribution occurred at about 170 min after treated with NPe6-PDT, and then sequestered into clusters associated with the mitochondira within 30 min. Our data clearly showed the spatial and temporal changes in Bax distribution in living cells during NPe6-induced apoptosis.

  3. Isolation and quantification of major chlorogenic acids in three major instant coffee brands and their potential effects on H2O2-induced mitochondrial membrane depolarization and apoptosis in PC-12 cells

    Coffee is a most consumed drink worldwide. In this paper, from three commercially available instant coffees, major chlorogenic acids were isolated and quantified using HPLC and NMR spectroscopic methods. Also, their anti-oxidant and anti-inflammatory activities were determined using DPPH-radical sca...

  4. Dicaffeoylquinic acids in Yerba mate (Ilex paraguariensis St. Hilaire) inhibit NF-kB nucleus translocation in macrophages and induce apoptosis by activating caspases-8 and -3 in human colon cancer cells

    Caffeoylquinic acid derivatives (CQAs) are widely distributed in plants including Yerba mate (Ilex paraguariensis). However, isolation of these isomers in Yerba mate and their anti-inflammatory and anti-colon cancer effects has not been studied. The objectives of this study were to isolate and purif...

  5. Effect of dicycloplatin, a novel platinum chemotherapeutical drug, on inhibiting cell growth and inducing cell apoptosis.

    Li, Guang-quan; Chen, Xing-gui; Wu, Xing-ping; Xie, Jing-dun; Liang, Yong-ju; Zhao, Xiao-qin; Chen, Wei-qiang; Fu, Li-wu

    2012-01-01

    Dicycloplatin, a new supramolecular platinum-based antitumor drug, has been approved by the State Food and Administration (SFDA) of China. In this study, we investigated the anticancer activity of dicycloplatin in cancer cells and signaling pathways involved in dicycloplatin-induced apoptosis. Dicycloplatin inhibited the proliferation of cancer cells and increased the percentage of apoptosis in a concentration-dependent manner. Besides, some apoptosis related events were observed after treatment with dicycloplatin, including increase of reactive oxygen species (ROS), collapse of mitochondrial membrane potential (Δψm), release of cytochrome c from the mitochondria to the cytosol, upregulation of p53, which were accompanied by activation of caspase-9, caspase-3, caspase-8, and poly (ADP-ribose) polymerase cleavage in a concentration-dependent manner. The role of apoptosis in dicycloplatin-mediated cell death was further confirmed by the concomitant treatment with caspase-8 or caspase-9 inhibitors, which inhibited apoptosis and PARP cleavage. Intracellular glutathione (GSH) was also found to inhibit the cytotoxic effect of dicycloplatin. In conclusion, these findings suggest that dicycloplatin induces apoptosis through ROS stress-mediated death receptor pathway and mitochondrial pathway which is similar to carboplatin. PMID:23152837

  6. Low-power laser irradiation inhibits amyloid beta-induced cell apoptosis

    Zhang, Heng; Wu, Shengnan

    2011-03-01

    The deposition and accumulation of amyloid-β-peptide (Aβ) in the brain are considered a pathological hallmark of Alzheimer's disease(AD). Apoptosis is a contributing pathophysiological mechanism of AD. Low-power laser irradiation (LPLI), a non-damage physical therapy, which has been used clinically for decades of years, is shown to promote cell proliferation and prevent apoptosis. Recently, low-power laser irradiation (LPLI) has been applied to moderate AD. In this study, Rat pheochromocytoma (PC12) cells were treated with amyloid beta 25-35 (Aβ25-35) for induction of apoptosis before LPLI treatment. We measured cell viability with CCK-8 according to the manufacture's protocol, the cell viability assays show that low fluence of LPLI (2 J/cm2 ) could inhibit the cells apoptosis. Then using statistical analysis of proportion of apoptotic cells by flow cytometry based on Annexin V-FITC/PI, the assays also reveal that low fluence of LPLI (2 J/cm2 ) could inhibit the Aβ-induced cell apoptosis. Taken together, we demonstrated that low fluence of LPLI (2 J/cm2 ) could inhibit the Aβ-induced cell apoptosis, these results directly point to a therapeutic strategy for the treatment of AD through LPLI.

  7. Short-form RON overexpression augments benzyl isothiocyanate-induced apoptosis in human breast cancer cells.

    Sehrawat, Anuradha; Singh, Shivendra V

    2016-05-01

    Chemoprevention of breast cancer is feasible with the use of non-toxic phytochemicals from edible and medicinal plants. Benzyl isothiocyanate (BITC) is one such plant compound that prevents mammary cancer development in a transgenic mouse model in association with tumor cell apoptosis. Prior studies from our laboratory have demonstrated a role for reactive oxygen species (ROS)-dependent Bax activation through the intermediary of c-Jun N-terminal kinases in BITC-induced apoptosis in human breast cancer cells. The present study demonstrates that truncated Recepteur d'Origine Nantais (sfRON) is a novel regulator of BITC-induced apoptosis in breast cancer cells. Overexpression of sfRON in MCF-7 and MDA-MB-361 cells resulted in augmentation of BITC-induced apoptosis when the apoptotic fraction was normalized against vehicle control for each cell type (untransfected and sfRON overexpressing cells). ROS generation and G2 /M phase cell cycle arrest resulting from BITC treatment were significantly attenuated in sfRON overexpressing cells after normalization with vehicle control for each cell type. Increased BITC-induced apoptosis by sfRON overexpression was independent of c-Jun N-terminal kinase or p38 mitogen-activated protein kinase hyperphosphorylation. On the other hand, activation of Bax and Bak following BITC exposure was markedly more pronounced in sfRON overexpressing cells than in controls. sfRON overexpression also augmented apoptosis induction by structurally diverse cancer chemopreventive phytochemicals including withaferin A, phenethyl isothiocyanate, and D,L-sulforaphane. In conclusion, the present study provides novel mechanistic insights into the role of sfRON in apoptosis regulation by BITC and other electrophilic phytochemicals. © 2015 Wiley Periodicals, Inc. PMID:25857724

  8. Glutathione Depletion Induced by c-Myc Downregulation Triggers Apoptosis on Treatment with Alkylating Agents

    Annamaria Biroccio

    2004-05-01

    Full Text Available Here we investigate the mechanism(s involved in the c-Myc-dependent drug response of melanoma cells. By using three M14-derived c-Myc low-expressing clones, we demonstrate that alkylating agents, cisplatin and melphalan, trigger apoptosis in the c-Myc antisense transfectants, but not in the parental line. On the contrary, topoisomerase inhibitors, adriamycin and camptothecin, induce apoptosis to the same extent regardless of c-Myc expression. Because we previously demonstrated that c-Myc downregulation decreases glutathione (GSH content, we evaluated the role of GSH in the apoptosis induced by the different drugs. In control cells treated with one of the alkylating agents or the others, GSH depletion achieved by L-buthionine-sulfoximine preincubation opens the apoptotic pathway. The apoptosis proceeded through early Bax relocalization, cytochrome c release, concomitant caspase-9 activation, whereas reactive oxygen species production and alteration of mitochondria membrane potential were late events. That GSH was determining in the c-Myc-dependent druginduced apoptosis was demonstrated by altering the intracellular GSH content of the c-Myc low-expressing cells up to the level of controls. Indeed, GSH ethyl ester-mediated increase of GSH abrogated apoptosis induced by cisplatin and melphalan by inhibition of Baxicytochrome c redistribution. The relationship among c-Myc, GSH content, the response to alkylating agent has been also evaluated in the M14 Myc overexpressing clones as well as in the melanoma JR8 c-Myc antisense transfectants. All together, these results demonstrate that GSH plays a key role in governing c-Myc-dependent drug-induced apoptosis.

  9. Canine distemper virus induces apoptosis in cervical tumor derived cell lines

    Rajão Daniela S

    2011-06-01

    Full Text Available Abstract Apoptosis can be induced or inhibited by viral proteins, it can form part of the host defense against virus infection, or it can be a mechanism for viral spread to neighboring cells. Canine distemper virus (CDV induces apoptotic cells in lymphoid tissues and in the cerebellum of dogs naturally infected. CDV also produces a cytopathologic effect, leading to apoptosis in Vero cells in tissue culture. We tested canine distemper virus, a member of the Paramyxoviridae family, for the ability to trigger apoptosis in HeLa cells, derived from cervical cancer cells resistant to apoptosis. To study the effect of CDV infection in HeLa cells, we examined apoptotic markers 24 h post infection (pi, by flow cytometry assay for DNA fragmentation, real-time PCR assay for caspase-3 and caspase-8 mRNA expression, and by caspase-3 and -8 immunocytochemistry. Flow cytometry showed that DNA fragmentation was induced in HeLa cells infected by CDV, and immunocytochemistry revealed a significant increase in the levels of the cleaved active form of caspase-3 protein, but did not show any difference in expression of caspase-8, indicating an intrinsic apoptotic pathway. Confirming this observation, expression of caspase-3 mRNA was higher in CDV infected HeLa cells than control cells; however, there was no statistically significant change in caspase-8 mRNA expression profile. Our data suggest that canine distemper virus induced apoptosis in HeLa cells, triggering apoptosis by the intrinsic pathway, with no participation of the initiator caspase -8 from the extrinsic pathway. In conclusion, the cellular stress caused by CDV infection of HeLa cells, leading to apoptosis, can be used as a tool in future research for cervical cancer treatment and control.

  10. Expression of hepatitis C virus envelope protein 2 induces apoptosis in cultured mammalian cells

    Li-Xin Zhu; Jing Liu; You-Hua Xie; Yu-Ying Kong; Ye Ye; Chun-Lin Wang; Guang-Di Li; Yuan Wang

    2004-01-01

    AIM: To explore the role of hepatitis C virus (HCV) envelope protein 2 (E2) in the induction of apoptosis.METHODS: A carboxyterminal truncated E2 (E2-661) was transiently expressed in several cultured mammalian cell lines or stably expressed in Chinese hamster ovary (CHO)cell line. Cell proliferation was assessed by 3H thymidine uptake. Apoptosis was examined by Hoechst 33258staining, flow cytometry and DNA fragmentation analysis.RESULTS: Reduced proliferation was readily observed in the E2-661 expressing cells. These cells manifested the typical features of apoptosis, including cell shrinkage,chromatin condensation and hypodiploid genomic DNA content. Similar apoptotic cell death was observed in an E2-661 stably expressing cell line.CONCLUSION: HCV E2 can induce apoptosis in cultured mammalian cells.

  11. Mitochondrial-derived ROS in edelfosine-induced apoptosis in yeasts and tumor cells

    Hui ZHANG; Consuelo GAJATE; Li-ping YU; Yun-xiang FANG; Faustino MOLLINEDO

    2007-01-01

    Aim: To investigate whether a similar process mediates cytotoxicity of 1-O-octadecyl-2-O-methyl-rac-glycero-3-phosphocholine (ET- 18-OCH3, edelfosine) in both yeasts and human tumor cells.Methods: A modified version of a previously described assay for the intracellular conversion of nitro blue tetrazolium to formazan by superoxide anion was used to measure the generation of reactive oxygen spe-cies (ROS). Apoptotic yeast cells were detected using terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay. DNA fragmenta-tion and the generation of ROS were measured by cytofluorimetric analysis in Jurkat cells.Results: Edelfosine induced apoptosis in Saccharomyces cerevisiae,as assessed by TUNEL assay. Meanwhile, edelfosine induced a time- and con-centration-dependent generation of ROS in yeasts. Rotenone, an inhibitor of the mitochondrial electron transport chain, prevented ROS generation and apoptosis in response to edelfosine in S cerevisiae, α-Tocopherol abrogated the edelfosine-induced generation of intracellular ROS and apoptosis. Edelfosine also induced an increase of ROS in human leukemic cells that preceded apoptosis. The overexpression of Bcl-2 by gene transfer abrogated both ROS generation and apoptosis induced by edelfosine in leukemic cells. Changes in the relative mito-chondrial membrane potential were detected in both yeasts and Jurkat cells.Conclusion: These results indicate that edelfosine induces apoptosis in yeasts in addition to human tumor cells, and this apoptotic process involves mitochondria,likely through mitochondrial-derived ROS. These data also suggest that yeasts can be used as a suitable cell model in elucidating the antitumor mechanism of action of edelfosine.

  12. Radiation-induced apoptosis in differentially modulated by PTK inhibitora in K562 cells

    The effect of PTK inhibitors (herbimycin A and genistein) on the induction of radiation-induced apoptosis in Ph-positive K562 leukemia cell line was investigated. K562 cells in exponential growth phase were irradiated with a linear accelerator at room temperature. For 6 MV X-ray irradiation and drug treatment, cultures were initiated at 2x106 cells/ml. The cells were irradiated with 10Gy. Stock solutions of herbimycin A and genistein were prepared in dimethyl sulphoxide (DMSO). After incubation at 37 .deg. for 0-48 h, the extent of apoptosis was determined using agarose gel electrophoresis and TUNEL assay. The progression of cells through the cell cycle after irradiation and drug treatment was also determined with flow cytometry. Western blot analysis was used to monitor bcl-2, bcl-X-L and bax protein levels. Treatment with 10 Gy X-irradiation did not result in the induction of apoptosis. The HMA alone (500 nM) also failed to induce apoptosis. By contrast, incubation of K562 cells with HMA after irradiation resulted in a substantial induction of nuclear condensation and fragmentation by agarose gel electrophoresis and TUNEL assay. Genistein failed to enhance the ability of X-irradiation to induce DNA fragmentation. Enhancement of apoptosis by HMA was not attributable to downregulation of the bcl-2 or bcl-X-L anti-apoptotic proteins. When the cells were irradiated and maintained with HMA, the percentage of cells in G2/M phase decreased to 30-40% at 48 h. On the other hand, cells exposed to 10 Gy X-irradiation alone or maintained with genistein did not show marked cell cycle redistribution. We have shown that nanomolar concentrations of the PTK inhibitor HMA synergize with X-irradiation in inducing the apoptosis in Ph (+) K562 leukemia cell line. While, genistein, a PTK inhibitor which is not selective for p210bcr/abl failed to enhance the radiation induced apoptosis in K562 cells. It is unlikely that the ability of HMA to enhance apoptosis in K562 cells is

  13. Phycocyanin prevents methylglyoxal-induced mitochondrial-dependent apoptosis in INS-1 cells by Nrf2.

    Gao, Yingnv; Liu, Chen; Wan, Guoqing; Wang, Xinshuo; Cheng, Xiaodong; Ou, Yu

    2016-02-01

    Methylglyoxal (MG) is a reactive dicarbonyl compound, whose abnormal accumulation in diabetic patients exerts deleterious effects on cells and tissues. The β-cell is the main target cell of Type 2 diabetes, and its insulin secretion injury and cell apoptosis can be due to mitochondrial dysfunction. Previous studies have demonstrated MG induced β-cell apoptosis. However, little is known about the effect of MG on β-cell mitochondrial dysfunction. Phycocyanin (PC) has been demonstrated to possess various biological activities including the effects on diabetic models in vivo. The aim of this study was to determine the protective effect of PC against methylglyoxal (MG)-induced dysfunction in pancreatic β-cell INS-1 and also the mechanism. We demonstrated that MG induced mitochondrial dysfunction by the decline in ATP levels, and the increase of the level of intracellular reactive oxygen s