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  1. Curcumin enhances the apoptosis-inducing potential of TRAIL in prostate cancer cells: molecular mechanisms of apoptosis, migration and angiogenesis

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    Shankar, Sharmila; Chen, Qinghe; Sarva, Krishna; Siddiqui, Imtiaz; Srivastava, Rakesh K

    2007-01-01

    Background: We have recently shown that curcumin (a diferuloylmethane) inhibits growth and induces apoptosis, and also demonstrated that TRAIL induces apoptosis by binding to specific cell surface death receptors in prostate cancer cells. The objectives of this paper were to investigate the molecular mechanisms by which curcumin enhanced the apoptosis-inducing potential of TRAIL in prostate cancer cells.Results: Curcumin enhanced the apoptosis-inducing potential of TRAIL in androgen-unrespons...

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

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    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.

  3. Ouabain enhances ADPKD cell apoptosis via the intrinsic pathway

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    Gustavo eBlanco

    2016-03-01

    Full Text Available Progression of autosomal dominant polycystic kidney disease (ADPKD is highly influenced by factors circulating in blood. We have shown that the hormone ouabain enhances several characteristics of the ADPKD cystic phenotype, including the rate of cell proliferation, fluid secretion and the capacity of the cells to form cysts. In this work, we found that physiological levels of ouabain (3nM also promote programmed cell death of renal epithelial cells obtained from kidney cysts of patients with ADPKD (ADPKD cells. This was determined by Alexa Fluor 488 labeled-Annexin-V staining and TUNEL assay, both biochemical markers of apoptosis. Ouabain-induced apoptosis also takes place when ADPKD cell growth is blocked; suggesting that the effect is not secondary to the stimulatory actions of ouabain on cell proliferation. Ouabain alters the expression of BCL family of proteins, reducing BCL-2 and increasing BAX expression levels, anti- and pro-apoptotic mediators respectively. In addition, ouabain caused the release of cytochrome c from mitochondria. Moreover, ouabain activates caspase-3, a key executioner caspase in the cell apoptotic pathway, but did not affect caspase-8. This suggests that ouabain triggers ADPKD cell apoptosis by stimulating the intrinsic, but not the extrinsic pathway of programmed cell death. The apoptotic effects of ouabain are specific for ADPKD cells and do not occur in normal human kidney cells (NHK cells. Taken together with our previous observations, these results show that ouabain causes an imbalance in cell growth/death, to favor growth of the cystic cells. This event, characteristic of ADPKD, further suggests the importance of ouabain as a circulating factor that promotes ADPKD progression.

  4. Chalcones Enhance TRAIL-Induced Apoptosis in Prostate Cancer Cells

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    Ewelina Szliszka; Zenon P. Czuba; Bogdan Mazur; Lukasz Sedek; Andrzej Paradysz; Wojciech Krol

    2009-01-01

    Chalcones exhibit chemopreventive and antitumor effects. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a naturally occurring anticancer agent that induces apoptosis in cancer cells and is not toxic to normal cells. We examined the cytotoxic and apoptotic effect of five chalcones in combination with TRAIL on prostate cancer cells. The cytotoxicity was evaluated by the MTT and LDH assays. The apoptosis was determined using flow cytometry with annexin V-FITC. Our study showe...

  5. Chalcones Enhance TRAIL-Induced Apoptosis in Prostate Cancer Cells

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    Szliszka, Ewelina; Czuba, Zenon P; Mazur, Bogdan; Sedek, Lukasz; Paradysz, Andrzej; Krol, Wojciech

    2009-01-01

    Chalcones exhibit chemopreventive and antitumor effects. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a naturally occurring anticancer agent that induces apoptosis in cancer cells and is not toxic to normal cells. We examined the cytotoxic and apoptotic effect of five chalcones in combination with TRAIL on prostate cancer cells. The cytotoxicity was evaluated by the MTT and LDH assays. The apoptosis was determined using flow cytometry with annexin V-FITC. Our study showed that all five tested chalcones: chalcone, licochalcone-A, isobavachalcone, xanthohumol, butein markedly augmented TRAIL-mediated apoptosis and cytotoxicity in prostate cancer cells and confirmed the significant role of chalcones in chemoprevention of prostate cancer. PMID:20161998

  6. Chalcones Enhance TRAIL-Induced Apoptosis in Prostate Cancer Cells

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    Ewelina Szliszka

    2009-12-01

    Full Text Available Chalcones exhibit chemopreventive and antitumor effects. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL is a naturally occurring anticancer agent that induces apoptosis in cancer cells and is not toxic to normal cells. We examined the cytotoxic and apoptotic effect of five chalcones in combination with TRAIL on prostate cancer cells. The cytotoxicity was evaluated by the MTT and LDH assays. The apoptosis was determined using flow cytometry with annexin V-FITC. Our study showed that all five tested chalcones: chalcone, licochalcone-A, isobavachalcone, xanthohumol, butein markedly augmented TRAIL-mediated apoptosis and cytotoxicity in prostate cancer cells and confirmed the significant role of chalcones in chemoprevention of prostate cancer.

  7. The MAPK pathway as an apoptosis enhancer in melanoma.

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    Haydn, Johannes M; Hufnagel, Anita; Grimm, Johannes; Maurus, Katja; Schartl, Manfred; Meierjohann, Svenja

    2014-07-15

    Inhibition of RAF/MEK/ERK signaling is beneficial for many patients with BRAF(V600E)-mutated melanoma. However, primary and secondary resistances restrict long-lasting therapy success. Combination therapies are therefore urgently needed. Here, we evaluate the cellular effect of combining a MEK inhibitor with a genotoxic apoptosis inducer. Strikingly, we observed that an activated MAPK pathway promotes in several melanoma cell lines the pro-apoptotic response to genotoxic stress, and MEK inhibition reduces intrinsic apoptosis. This goes along with MEK inhibitor induced increased RAS and P-AKT levels. The protective effect of the MEK inhibitor depends on PI3K signaling, which prevents the induction of pro-apoptotic PUMA that mediates apoptosis after DNA damage. We could show that the MEK inhibitor dependent feedback loop is enabled by several factors, including EGF receptor and members of the SPRED family. The simultaneous knockdown of SPRED1 and SPRED2 mimicked the effects of MEK inhibitor such as PUMA repression and protection from apoptosis. Our data demonstrate that MEK inhibition of BRAF(V600E)-positive melanoma cells can protect from genotoxic stress, thereby achieving the opposite of the intended anti-tumorigenic effect of the combination of MEK inhibitor with inducers of intrinsic apoptosis.

  8. Reduction of decoy receptor 3 enhances TRAIL-mediated apoptosis in pancreatic cancer.

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    Wei Wang

    Full Text Available Most human pancreatic cancer cells are resistant to tumor necrosis factor (TNF-related apoptosis-inducing ligand (TRAIL-mediated apoptosis. However, the mechanisms by which pancreatic cancer cells utilize their extracellular molecules to counteract the proapoptotic signaling mediated by the TNF family are largely unknown. In this study, we demonstrate for the first time that DcR3, a secreted decoy receptor that malignant pancreatic cancer cells express at a high level, acts as an extracellular antiapoptotic molecule by binding to TRAIL and counteracting its death-promoting function. The reduction of DcR3 with siRNA unmasked TRAIL and greatly enhanced TRAIL-induced apoptosis. Gemcitabine, a first-line drug for pancreatic cancer, also reduced the level of DcR3. The addition of DcR3 siRNA further enhanced gemcitabine-induced apoptosis. Notably, our in vivo study demonstrated that the therapeutic effect of gemcitabine could be enhanced via further reduction of DcR3, suggesting that downregulation of DcR3 in tumor cells could tip the balance of pancreatic cells towards apoptosis and potentially serve as a new strategy for pancreatic cancer therapy.

  9. Nonsteroidal anti-inflammatory drugs induce apoptosis in cutaneous T-cell lymphoma cells and enhance their sensitivity for TNF-related apoptosis-inducing ligand.

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    Braun, Frank K; Al-Yacoub, Nadya; Plötz, Michael; Möbs, Markus; Sterry, Wolfram; Eberle, Jürgen

    2012-02-01

    Cutaneous T-cell lymphomas (CTCL) form a heterogeneous group of non-Hodgkin's lymphomas of the skin. In previous studies, we had characterized CTCL cells as resistant to the death ligand tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), which correlated to pronounced expression of the caspase-8/-10 inhibitor c-FLIP. For identification of proapoptotic strategies in CTCL cells and for overcoming their death ligand resistance, we investigated the effects of nonsteroidal anti-inflammatory drugs (NSAIDs) such as acetylsalicylic acid, sodium salicylate, and diclofenac (DF). These drugs strongly enhanced apoptosis, as well as decreased CTCL cell proliferation and vitality, and DF furthermore sensitized for TRAIL-induced apoptosis. Full activation of the caspase cascade (caspase-3, -8, -9) and decreased mitochondrial membrane potential were characteristic for NSAID treatment, whereas cytochrome c release was seen only for DF. Downregulation of Mcl-1 and enhanced surface expression of TRAIL were seen in response to NSAIDs. Most characteristic for apoptosis induction was the downregulation of c-FLIP. In agreement with the critical role of c-FLIP for apoptosis deficiency of CTCL cells, its overexpression decreased NSAID-mediated apoptosis and its downregulation by small hairpin RNA-enhanced apoptosis. The study provides a rationale for the use of NSAIDs as a new therapeutic option for CTCL patients. Supporting this concept, ex vivo lymphoma cells of CTCL patients also revealed significant sensitivity for NSAID treatment.

  10. Lymphocytes from wasted mice express enhanced spontaneous and {gamma}-ray-induced apoptosis

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    Woloschak, G.E. [Argonne National Lab., IL (United States)]|[Loyola Univ. Medical Center, Maywood, IL (United States); Chang-Liu, Chin-Mei [Argonne National Lab., IL (United States); Chung, Jen; Libertin, C.R. [Loyola Univ. Medical Center, Maywood, IL (United States)

    1993-09-01

    Mice bearing the autosomal recessive mutation wasted (wst/wst) display a disease pattern including faulty repair of DNA damage in lymphocytes after radiation exposure, neurologic abnormalities, and immunodeficiency. Many of the features of this mouse model have suggested a premature or increased spontaneous frequency of apoptosis in thymocytes; past work has shown an inability to establish cultured T cell lines, an abnormally high death rate of stimulated T cells in culture, and an increased sensitivity of T cells to the killing effects of ionizing radiations in wst/wst mice relative to controls. The experiments reported here were designed to examine splenic and thymic lymphocytes from wasted and control mice for signs of early apoptosis. Our results revealed enhanced expression of Rp-8 mRNA (associated with apoptosis) in thymic lymphocytes and reduced expression in splenic lymphocytes of wst/wst mice relative to controls; expression of Rp-2 and Td-30 mRNA (induced during apoptosis) were not detectable in spleen or thymus. Higher spontaneous DNA fragmentation was observed in wasted mice than in controls; however, {gamma}-ray-induced DNA fragmentation peaked at a lower dose and occurred to a greater extent in wasted mice relative to controls. These results provide evidence for high spontaneous and {gamma}-ray-induced apoptosis in T cells of wasted mice as a mechanism underlying the observed lymphocyte and DNA repair abnormalities.

  11. PI3K inhibition enhances doxorubicin-induced apoptosis in sarcoma cells.

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    Diana Marklein

    Full Text Available We searched for a drug capable of sensitization of sarcoma cells to doxorubicin (DOX. We report that the dual PI3K/mTOR inhibitor PI103 enhances the efficacy of DOX in several sarcoma cell lines and interacts with DOX in the induction of apoptosis. PI103 decreased the expression of MDR1 and MRP1, which resulted in DOX accumulation. However, the enhancement of DOX-induced apoptosis was unrelated to DOX accumulation. Neither did it involve inhibition of mTOR. Instead, the combination treatment of DOX plus PI103 activated Bax, the mitochondrial apoptosis pathway, and caspase 3. Caspase 3 activation was also observed in xenografts of sarcoma cells in nude mice upon combination of DOX with the specific PI3K inhibitor GDC-0941. Although the increase in apoptosis did not further impact on tumor growth when compared to the efficient growth inhibition by GDC-0941 alone, these findings suggest that inhibition of PI3K may improve DOX-induced proapoptotic effects in sarcoma. Taken together with similar recent studies of neuroblastoma- and glioblastoma-derived cells, PI3K inhibition seems to be a more general option to sensitize tumor cells to anthracyclines.

  12. Propranolol enhanced adipogenesis instead of induction of apoptosis of hemangiomas stem cells

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    Ma, Xiaorong; Zhao, Tinghui; Ouyang, Tianxiang; Xin, Shujia; Ma, Yueting; Chang, Mengling

    2014-01-01

    Propranolol has been widely used in treating infantile hemangiomas (IHs). But recurrence of IHs was found in some cases on cessation of propranolol treatment. The other is that Chinese individuals reacted to propranolol differently from American Whites. Whether the difference of sensitivity is due to the β adrenoceptor (β-AR) expression pattern of hemangioma initiating cells remains unclear. In the present study, we isolated hemangioma-derived stem cells (hemSCs) from proliferative IHs and analyzed the biological characteristics and β-AR expression pattern of hemSCs by immunostaining, Western blotting and multilineage differentiation assay as well. We also tested the effects of propranolol on hemSCs by evaluating VEGF expression, proliferation and apoptosis related parameters. Our results indicated that CD133+ hemSCs located pre-vascular in proiferative IH tissues. Both β1 and β2-AR were expressed, while β2-AR was dominant on hemSCs. Propranolol at 100-150 μM inhibited proliferation of hemSCs, not did 50 μM. Propranolol down-regulated VEGF expression of hemSCs, instead of inducing apoptosis. The adipogenic potential was enhanced by propranolol. Therefore, our current results suggested propranolol could not induce apoptosis of hemSCs, but played a curative role though suppressing VEGF synthesis and enhancement of adipogenesis of hemSCs. Our results might partially provide the insight of mechanism of relapse in some cases on cessation of propranolol treatment. PMID:25120757

  13. ABT-737, Synergistically Enhances Daunorubicin-Mediated Apoptosis in Acute Myeloid Leukemia Cell Lines

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    Hassan Dariushnejad

    2014-03-01

    Full Text Available Purpose: Intensive chemotherapy with daunorubicin (DNR is associated with serious side effects in acute myeloid leukemia (AML patients. In this study the effect of small-molecule BH3-mimetic, ABT-737, on the sensitivity of HL60 and U937 AML cell lines was investigated. Methods: The cytotoxic effects of DNR and ABT-737, alone or in combination were assessed using MTT assay and combination index analysis. The effects of treatments on the cell proliferation was determined by trypan blue assay. ELISA cell death assay was used for measurement of apoptosis. Results: IC50 values of DNR and ABT-737 were 2.52 and 0.59 μM for HL-60 cells line and 1.31 and 0.80 μM for U937 cell line at 24 h, respectively. Surprisingly, combination treatment significantly lowered the IC50 values in a synergic manner in both cell lines. Moreover, treatment with a mixture of two agents had more growth inhibition effect relative to the monotherapy. Results of apoptosis assay showed that the cytotoxic effects are related to the enhancement of apoptosis. Conclusion: Our study suggests that ABT-737 synergistically enhances the cytotoxic effect of DNR in AML cell lines and therefore may be useful to overcome chemoresistance of leukemia patients.

  14. TNF-related apoptosis-inducing ligand enhances vinorelbine-induced apoptosis and antitumor activity in a preclinical model of non-small cell lung cancer.

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    Zhu, Kunshou; Fang, Weimin; Chen, Yuanmei; Lin, Shaofeng; Chen, Xiaohui

    2014-09-01

    Non-small cell lung cancer (NSCLC) is relatively insensitive to chemotherapy. NP [vinorelbine (NVB) + cisplatin] is the standard chemotherapy regimen in clinical treatment; however, its side-effects are intolerable for most patients. In some reports, the TNF-related apoptosis-inducing ligand (TRAIL) can enhance the sensitivity of chemotherapy drugs by inducing apoptosis without toxicity to normal cells. In the present study, we evaluated the antitumor effects of the two drugs (TRAIL and NVB alone or in combination) by inducing apoptosis in vitro and in vivo. Using the human NSCLC cell line (A549) and a BALB/c nude mice model, we observed the cell viability (MTT assay), cell apoptosis [Hoechst staining, Annexin V/propidium iodide (PI) staining assay, immunohistochemical staining, RT-PCR and western blotting] and cell proliferation (soft agar colony formation and cell cycle assay). The results showed that TRAIL and NVB alone inhibited tumor growth both in vivo and in vitro. However, the combination of the two drugs produced a more potent antitumor effect (Papoptosis in tumor tissue (Pinduced a more potent apoptosis than either drug alone (Papoptosis Papoptosis pathway.

  15. Apoptosis induced by ultraviolet radiation is enhanced by amplitude modulated radiofrequency radiation in mutant yeast cells.

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    Markkanen, Ari; Penttinen, Piia; Naarala, Jonne; Pelkonen, Jukka; Sihvonen, Ari-Pekka; Juutilainen, Jukka

    2004-02-01

    The aim of this study was to investigate whether radiofrequency (RF) electromagnetic field (EMF) exposure affects cell death processes of yeast cells. Saccharomyces cerevisiae yeast cells of the strains KFy417 (wild-type) and KFy437 (cdc48-mutant) were exposed to 900 or 872 MHz RF fields, with or without exposure to ultraviolet (UV) radiation, and incubated simultaneously with elevated temperature (+37 degrees C) to induce apoptosis in the cdc48-mutated strain. The RF exposure was carried out in a special waveguide exposure chamber where the temperature of the cell cultures can be precisely controlled. Apoptosis was analyzed using the annexin V-FITC method utilizing flow cytometry. Amplitude modulated (217 pulses per second) RF exposure significantly enhanced UV induced apoptosis in cdc48-mutated cells, but no effect was observed in cells exposed to unmodulated fields at identical time-average specfic absorption rates (SAR, 0.4 or 3.0 W/kg). The findings suggest that amplitude modulated RF fields, together with known damaging agents, can affect the cell death process in mutated yeast cells. Bioelectromagnetics 25:127-133, 2004. Copyright 2004 Wiley-Liss, Inc.

  16. Driving p53 Response to Bax Activation Greatly Enhances Sensitivity to Taxol by Inducing Massive Apoptosis

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    Paola De Feudis

    2000-05-01

    Full Text Available The proapoptotic gene bax is one of the downstream effectors of p53. The p53 binding site in the bax promoter is less responsive to p53 than the one in the growth arrest mediating gene p21. We introduced the bax gene under the control of 13 copies of a strong p53 responsive element into two ovarian cancer cell lines. The clones expressing bax under the control of p53 obtained from the wild-type (wt p53-expressing cell line A2780 were much more sensitive (500- to 1000-fold to the anticancer agent taxol than the parent cell line, with a higher percentage of cells undergoing apoptosis after drug treatment that was clearly p53-dependent and bax-mediated. Xenografts established in nude mice from one selected clone (A2780/C3 were more responsive to taxol than the parental line and the apoptotic response of A2780/C3 tumors was also increased after treatment. Introduction of the same plasmid into the p53 null SKOV3 cell line did not alter the sensitivity to taxol or the induction of apoptosis. In conclusion, driving the p53 response (after taxol treatment by activating the bax gene rather than the p21 gene results in induction of massive apoptosis, in vitro and in vivo, and greatly enhances sensitivity to the drug.

  17. Driving p53 Response to Bax Activation Greatly Enhances Sensitivity to Taxol by Inducing Massive Apoptosis

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    De Feudis, Paola; Vignati, Sara; Rossi, Cosmo; Mincioni, Tatiana; Giavazzi, Raffaella; D'Incalci, Maurizio; Broggini, Massimo

    2000-01-01

    Abstract The proapoptotic gene bax is one of the downstream effectors of p53. The p53 binding site in the bax promoter is less responsive to p53 than the one in the growth arrest mediating gene p21. We introduced the bax gene under the control of 13 copies of a strong p53 responsive element into two ovarian cancer cell lines. The clones expressing bax under the control of p53 obtained from the wild-type (wt) p53-expressing cell line A2780 were much more sensitive (500- to 1000-fold) to the anticancer agent taxol than the parent cell line, with a higher percentage of cells undergoing apoptosis after drug treatment that was clearly p53-dependent and bax-mediated. Xenografts established in nude mice from one selected clone (A2780/C3) were more responsive to taxol than the parental line and the apoptotic response of A2780/C3 tumors was also increased after treatment. Introduction of the same plasmid into the p53 null SKOV3 cell line did not alter the sensitivity to taxol or the induction of apoptosis. In conclusion, driving the p53 response (after taxol treatment) by activating the bax gene rather than the p21 gene results in induction of massive apoptosis, in vitro and in vivo, and greatly enhances sensitivity to the drug. PMID:10935506

  18. Cathepsin inhibition-induced lysosomal dysfunction enhances pancreatic beta-cell apoptosis in high glucose.

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    Minjeong Jung

    Full Text Available Autophagy is a lysosomal degradative pathway that plays an important role in maintaining cellular homeostasis. We previously showed that the inhibition of autophagy causes pancreatic β-cell apoptosis, suggesting that autophagy is a protective mechanism for the survival of pancreatic β-cells. The current study demonstrates that treatment with inhibitors and knockdown of the lysosomal cysteine proteases such as cathepsins B and L impair autophagy, enhancing the caspase-dependent apoptosis of INS-1 cells and islets upon exposure to high concentration of glucose. Interestingly, treatment with cathepsin B and L inhibitors prevented the proteolytic processing of cathepsins B, D and L, as evidenced by gradual accumulation of the respective pro-forms. Of note, inhibition of aspartic cathepsins had no effect on autophagy and cell viability, suggesting the selective role of cathepsins B and L in the regulation of β-cell autophagy and apoptosis. Lysosomal localization of accumulated pro-cathepsins in the presence of cathepsin B and L inhibitors was verified via immunocytochemistry and lysosomal fractionation. Lysotracker staining indicated that cathepsin B and L inhibitors led to the formation of severely enlarged lysosomes in a time-dependent manner. The abnormal accumulation of pro-cathepsins following treatment with inhibitors of cathepsins B and L suppressed normal lysosomal degradation and the processing of lysosomal enzymes, leading to lysosomal dysfunction. Collectively, our findings suggest that cathepsin defects following the inhibition of cathepsin B and L result in lysosomal dysfunction and consequent cell death in pancreatic β-cells.

  19. Enhanced glycogen synthase kinase-3β activity mediates podocyte apoptosis under diabetic conditions.

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    Paeng, Jisun; Chang, Jae Hyun; Lee, Sun Ha; Nam, Bo Young; Kang, Hye-Young; Kim, Seonghun; Oh, Hyung Jung; Park, Jung Tak; Han, Seung Hyeok; Yoo, Tae-Hyun; Kang, Shin-Wook

    2014-12-01

    Glycogen synthase kinase-3β (GSK-3β) is involved in the pathogenesis of various kidney diseases. This study was undertaken to examine the changes in GSK-3β activity in podocytes under diabetic conditions and to elucidate the functional role of GSK-3β in podocyte apoptosis. In vivo, 32 rats were injected with either diluent (n = 16, C) or with streptozotocin intraperitoneally (n = 16, DM), and 8 rats from each group were treated with 6-bromoindirubin-3'-oxime (BIO) for 3 months. In vitro, immortalized mouse podocytes were exposed to 5.6 mM glucose or 30 mM glucose (HG) with or without 10 μM BIO. Western blot analysis and TUNEL or Hoechst 33342 staining were performed to identify apoptosis. Urinary albumin excretion was significantly higher in DM rats, and this increase was significantly abrogated in DM rats by BIO treatment. The protein expression of Tyr216-phospho-GSK-3β was significantly increased in DM glomeruli and in cultured podocytes exposed to HG. Western blot analysis revealed that the protein expression of Bax and active fragments of caspase-3 were significantly increased, whereas phospho-Akt, β-catenin, and Bcl-2 protein expression were significantly decreased in DM glomeruli and HG-stimulated podocytes. Apoptosis, determined by TUNEL assay and Hoechst 33342 staining, was also significantly increased in podocytes under diabetic conditions. The changes in the expression of apoptosis-related molecules and the increase in the number of apoptotic cells in DM glomeruli as well as in HG-stimulated podocytes were significantly ameliorated by BIO. These findings suggest that enhanced GSK-3β activity within podocytes under diabetic conditions is associated with podocyte loss in diabetic nephropathy.

  20. TNF-related apoptosis-inducing ligand deficiency enhances survival in murine colon ascendens stent peritonitis

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    Beyer K

    2016-06-01

    Full Text Available Katharina Beyer,1 Laura Stollhof,1 Christian Poetschke,2 Wolfram von Bernstorff,1 Lars Ivo Partecke,1 Stephan Diedrich,1 Stefan Maier,1 Barbara M Bröker,2 Claus-Dieter Heidecke1 1Department of General, Visceral, Thoracic, and Vascular Surgery, 2Institute of Immunology, University of Greifswald, Greifswald, GermanyBackground: Apart from inducing apoptosis in tumor cells, tumor necrosis factor (TNF-related apoptosis-inducing ligand (TRAIL influences inflammatory reactions. Murine colon ascendens stent peritonitis (CASP represents a model of diffuse peritonitis. Recently, it has been demonstrated that administration of exogenous TRAIL not only induces apoptosis in neutrophils but also enhances survival in this model. The aim of this study was to examine the impact of genetic TRAIL deficiency on the course of CASP.Methods: Peritonitis was induced in 6- to 8-week-old female TRAIL−/− mice as well as in wild-type mice. The sepsis severity score and survival of mice were monitored. Bacterial loads in blood as well as in the lymphoid organs were examined. Additionally, the number of apoptotic cells within the lymphoid organs was determined.Results: As early as 8 hours postinduction of CASP, TRAIL−/− mice were significantly more affected by sepsis than wild-type mice, as measured by the sepsis severity score. However, during the further course of sepsis, TRAIL deficiency led to significantly decreased sepsis severity scores, resulting in an enhanced overall survival in TRAIL−/− mice. The better survival of TRAIL−/− mice was accompanied by a decreased bacterial load within the blood. In marked contrast, the number of apoptotic cells within the lymphoid organs was highly increased in TRAIL−/− mice 20 hours after induction of CASP.Conclusion: Hence, exogenous and endogenous TRAIL is protective during the early phase of sepsis, while endogenous TRAIL appears to be detrimental in the later course of this disease.Keywords: CASP, mice

  1. Retinoids enhance glucocorticoid-induced apoptosis of T cells by facilitating glucocorticoid receptor-mediated transcription

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    Tóth, K; Sarang, Z; Scholtz, B; Brázda, P; Ghyselinck, N; Chambon, P; Fésüs, L; Szondy, Z

    2011-01-01

    Glucocorticoid-induced apoptosis of thymocytes is one of the first recognized forms of programmed cell death. It was shown to require gene activation induced by the glucocorticoid receptor (GR) translocated into the nucleus following ligand binding. In addition, the necessity of the glucocorticoid-induced, but transcription-independent phosphorylation of phosphatidylinositol-specific phospholipase C (PI-PLC) has also been shown. Here we report that retinoic acids, physiological ligands for the nuclear retinoid receptors, enhance glucocorticoid-induced death of mouse thymocytes both in vitro and in vivo. The effect is mediated by retinoic acid receptor (RAR) alpha/retinoid X receptor (RXR) heterodimers, and occurs when both RARα and RXR are ligated by retinoic acids. We show that the ligated RARα/RXR interacts with the ligated GR, resulting in an enhanced transcriptional activity of the GR. The mechanism through which this interaction promotes GR-mediated transcription does not require DNA binding of the retinoid receptors and does not alter the phosphorylation status of Ser232, known to regulate the transcriptional activity of GR. Phosphorylation of PI-PLC was not affected. Besides thymocytes, retinoids also promoted glucocorticoid-induced apoptosis of various T-cell lines, suggesting that they could be used in the therapy of glucocorticoid-sensitive T-cell malignancies. PMID:21072052

  2. Hyperbaric oxygen enhances neutrophil apoptosis and their clearance by monocyte-derived macrophages.

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    Almzaiel, Anwar J; Billington, Richard; Smerdon, Gary; Moody, A John

    2015-08-01

    Neutrophil apoptosis and clearance by macrophages are essential for wound healing. Evidence suggests that hyperbaric oxygen (HBO) exposure may enhance neutrophil apoptosis, but HBO effects leading to neutrophil clearance by macrophages are still unclear. In the current study, bovine neutrophils and monocyte-derived macrophages (MDMΦ) were co-cultured under HBO (97.9% O2, 2.1% CO2 at 2.4 atm absolute (ATA)) (1 atm = 101.325 kPa), hyperbaric normoxia (8.8% O2 at 2.4 ATA), normobaric hyperoxia (95% O2, 5% CO2), normoxia (air), and normobaric hypoxia (5% O2, 5% CO2). Phagocytosis of fresh and 22 h aged neutrophils by MDMΦ was increased after HBO pre-treatment, assessed using flow cytometry and light microscopy. Enhanced clearance of neutrophils was accompanied by an increase in H2O2 levels following HBO pre-treatment with upregulation of IL-10 (anti-inflammatory cytokine) mRNA expression in LPS-stimulated MDMΦ that had ingested aged neutrophils. TNF-α (pro-inflammatory cytokine) gene expression did not change in LPS-stimulated MDMΦ that had ingested fresh or aged neutrophils after HBO, pressure, and hyperoxia. These findings suggest that HBO-activated MDMΦ participate in the clearance of apoptotic cells. Uptake of neutrophils by MDMΦ exposed to HBO may contribute to resolution of inflammation, because HBO induced up-regulation of IL-10 mRNA expression.

  3. DNA Tetrahedron Delivery Enhances Doxorubicin-Induced Apoptosis of HT-29 Colon Cancer Cells

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    Zhang, Guiyu; Zhang, Zhiyong; Yang, Junen

    2017-08-01

    As a nano-sized drug carrier with the advantage of modifiability and proper biocompatibility, DNA tetrahedron (DNA tetra) delivery is hopeful to enhance the inhibitory efficiency of nontargeted anticancer drugs. In this investigation, doxorubicin (Dox) was assembled to a folic acid-modified DNA tetra via click chemistry to prepare a targeted antitumor agent. Cellular uptake efficiency was measured via fluorescent imaging. Cytotoxicity, inhibition efficiency, and corresponding mechanism on colon cancer cell line HT-29 were evaluated by MTT assay, cell proliferation curve, western blot, and flow cytometry. No cytotoxicity was induced by DNA tetra, but the cellular uptake ratio increased obviously resulting from the DNA tetra-facilitated penetration through cellular membrane. Accordingly, folic acid-DNA tetra-Dox markedly increased the antitumor efficiency with increased apoptosis levels. In details, 100 μM was the effective concentration and a 6-h incubation period was needed for apoptosis induction. In conclusion, nano-sized DNA tetrahedron was a safe and effective delivery system for Dox and correspondingly enhanced the anticancer efficiency.

  4. Targeting Aerobic Glycolysis and HIF-1α Expression Enhance Imiquimod-induced Apoptosis in Cancer Cells

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    Huang, Shi-Wei; Kao, Jun-Kai; Wu, Chun-Ying; Wang, Sin-Ting; Lee, Hsin-Chen; Liang, Shu-Mei; Chen, Yi-Ju; Shieh, Jeng-Jer

    2014-01-01

    Tumor cells rely on aerobic glycolysis to maintain unconstrained cell growth and proliferation. Imiquimod (IMQ), a synthetic Toll-like receptor (TLR) 7/8 ligand, exerts anti-tumor effects directly by inducing cell death in cancer cells and/or indirectly by activating cellular immune responses against tumor cells. However, whether IMQ modulates glucose metabolism pathways remains unclear. In this study, we demonstrated that IMQ can enhance aerobic glycolysis by up-regulating HIF-1α expression at the transcriptional and translational levels via ROS mediated STAT3- and Akt-dependent pathways, independent of TLR7/8 signaling. The genetic silencing of HIF-1α not only repressed IMQ-induced aerobic glycolysis but also sensitized cells to IMQ-induced apoptosis due to faster ATP and Mcl-1 depletion. Moreover, the glucose analog 2-DG and the Hsp90 inhibitor 17-AAG, which destabilizes the HIF-1α protein, synergized with IMQ to induce tumor cell apoptosis in vitro and significantly inhibited tumor growth in vivo. Thus, we hypothesize that the IMQ-induced up-regulation of HIF-1α and aerobic glycolysis is a protective response to the metabolic stress generated by IMQ treatment, and thus, co-treatment with inhibitors of HIF-1α and/or glycolysis may be a useful therapeutic strategy to enhance the anti-tumor effects of IMQ in clinical settings. PMID:24658058

  5. Hepatocyte growth factor enhances death receptor-induced apoptosis by up-regulating DR5

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    Goodwin C Rory

    2008-11-01

    Full Text Available Abstract Background Hepatocyte growth factor (HGF and its receptor c-MET are commonly expressed in malignant gliomas and embryonic neuroectodermal tumors including medulloblastoma and appear to play an important role in the growth and dissemination of these malignancies. Dependent on cell context and the involvement of specific downstream effectors, both pro- and anti-apoptotic effects of HGF have been reported. Methods Human medulloblastoma cells were treated with HGF for 24–72 hours followed by death receptor ligand TRAIL (Tumor necrosis factor-related apoptosis-inducing ligand for 24 hours. Cell death was measured by MTT and Annexin-V/PI flow cytometric analysis. Changes in expression levels of targets of interest were measured by Northern blot analysis, quantitative reverse transcription-PCR, Western blot analysis as well as immunoprecipitation. Results In this study, we show that HGF promotes medulloblastoma cell death induced by TRAIL. TRAIL alone triggered apoptosis in DAOY cells and death was enhanced by pre-treating the cells with HGF for 24–72 h prior to the addition of TRAIL. HGF (100 ng/ml enhanced TRAIL (10 ng/ml induced cell death by 36% (P Conclusion Taken together, these and previous findings indicate that HGF:c-Met pathway either promotes or inhibits medulloblastoma cell death via pathway and context specific mechanisms.

  6. Inhibiting ROS-TFEB-Dependent Autophagy Enhances Salidroside-Induced Apoptosis in Human Chondrosarcoma Cells.

    Science.gov (United States)

    Zeng, Wei; Xiao, Tao; Cai, Anlie; Cai, Weiliang; Liu, Huanhuan; Liu, Jingling; Li, Jie; Tan, Miduo; Xie, Li; Liu, Ying; Yang, Xiangcheng; Long, Yi

    2017-01-01

    Autophagy modulation has been considered a potential therapeutic strategy for human chondrosarcoma, and a previous study indicated that salidroside exhibits significant anti-carcinogenic activity. However, the ability of salidroside to induce autophagy and its role in human chondrosarcoma cell death remains unclear. We exposed SW1353 cells to different concentrations of salidroside (0.5, 1 and 2 mM) for 24 h. RT-PCR, Western-blotting, Immunocytofluorescence, and Luciferase Reporter Assays were used to evaluate whether salidroside activated the TFEB-dependent autophagy. We show that salidroside induced significant apoptosis in the human chondrosarcoma cell line SW1353. In addition, we demonstrate that salidroside-induced an autophagic response in SW1353 cells, as evidenced by the upregulation of LC3-II and downregulation of P62. Moreover, pharmacological or genetic blocking of autophagy enhanced salidroside -induced apoptosis, indicating the cytoprotective role of autophagy in salidroside-treated SW1353 cells. Salidroside also induced TFEB (Ser142) dephosphorylation, subsequently to activated TFEB nuclear translocation and increase of TFEB reporter activity, which contributed to lysosomal biogenesis and the expression of autophagy-related genes. Importantly, we found that salidroside triggered the generation of ROS in SW1353 cells. Furthermore, NAC, a ROS scavenger, abrogated the effects of salidroside on TFEB-dependent autophagy. These data demonstrate that salidroside increased TFEB-dependent autophagy by activating ROS signaling pathways in human chondrosarcoma cells. These data also suggest that blocking ROS-TFEB-dependent autophagy to enhance the activity of salidroside warrants further attention in treatment of human chondrosarcoma cells. © 2017 The Author(s). Published by S. Karger AG, Basel.

  7. Sequential gemcitabine and tamoxifen treatment enhances apoptosis and blocks transformation in bladder cancer cells.

    Science.gov (United States)

    Takeuchi, Hisashi; Mmeje, Chinedu O; Jinesh, Goodwin G; Taoka, Rikiya; Kamat, Ashish M

    2015-11-01

    Bladder cancer is a common malignancy for which regional or metastatic disease is identified at diagnosis. The aim of this study was to determine whether tamoxifen (Tam), an estrogen receptor (ER) antagonist, can sensitize bladder cancer cell lines to gemcitabine (Gem) chemotherapy. ERα and ERβ protein levels were determined in each cell line using western blot analysis. The TCC-Sup, 5637, and RT4 bladder cancer cells were exposed to various concentrations and regimens of Tam or Gem alone or in combination. Cell viability and apoptosis were assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and propidium iodide followed by flow cytometry. Apoptosis was then evaluated by western blot analysis. Treated TCC-Sup cells were subjected to soft agar colony formation assay to determine the cellular transformation. Western blot analysis results revealed ER expression in the three cell lines. TCC-Sup and 5637 cells treated with a combination of Tam and Gem had lower cell viabilities than those treated with Tam or Gem alone for 72 h in TCC-Sup and 5637. Compared with the other treatments, sequential Gem followed by Tam (Gem→Tam) treatment caused the largest increase in DNA fragmentation at 72 h in TCC-Sup cells. Western blot analysis results revealed that this sequential Gem→Tam treatment increased poly(ADP-ribose) polymerase cleavage in TCC-Sup cells. Sequential Gem→Tam inhibited the cell transformation in TCC-Sup cells. In conclusion, sequential Gem→Tam enhanced the cytotoxicity of Gem in vitro. This regimen be useful to enhance the efficacy of Gem in bladder cancer. However, future in vivo studies are required to verify the results.

  8. Inhibiting ROS-TFEB-Dependent Autophagy Enhances Salidroside-Induced Apoptosis in Human Chondrosarcoma Cells

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    Wei Zeng

    2017-10-01

    Full Text Available Background/Aims: Autophagy modulation has been considered a potential therapeutic strategy for human chondrosarcoma, and a previous study indicated that salidroside exhibits significant anti-carcinogenic activity. However, the ability of salidroside to induce autophagy and its role in human chondrosarcoma cell death remains unclear. Methods: We exposed SW1353 cells to different concentrations of salidroside (0.5, 1 and 2 mM for 24 h. RT-PCR, Western-blotting, Immunocytofluorescence, and Luciferase Reporter Assays were used to evaluate whether salidroside activated the TFEB-dependent autophagy. Results: We show that salidroside induced significant apoptosis in the human chondrosarcoma cell line SW1353. In addition, we demonstrate that salidroside-induced an autophagic response in SW1353 cells, as evidenced by the upregulation of LC3-II and downregulation of P62. Moreover, pharmacological or genetic blocking of autophagy enhanced salidroside -induced apoptosis, indicating the cytoprotective role of autophagy in salidroside-treated SW1353 cells. Salidroside also induced TFEB (Ser142 dephosphorylation, subsequently to activated TFEB nuclear translocation and increase of TFEB reporter activity, which contributed to lysosomal biogenesis and the expression of autophagy-related genes. Importantly, we found that salidroside triggered the generation of ROS in SW1353 cells. Furthermore, NAC, a ROS scavenger, abrogated the effects of salidroside on TFEB-dependent autophagy. Conclusions: These data demonstrate that salidroside increased TFEB-dependent autophagy by activating ROS signaling pathways in human chondrosarcoma cells. These data also suggest that blocking ROS-TFEB-dependent autophagy to enhance the activity of salidroside warrants further attention in treatment of human chondrosarcoma cells.

  9. TAK1 inhibitor NG25 enhances doxorubicin-mediated apoptosis in breast cancer cells.

    Science.gov (United States)

    Wang, Zhenyu; Zhang, Huiyuan; Shi, Minghao; Yu, Yang; Wang, Hao; Cao, Wen-Ming; Zhao, Yanling; Zhang, Hong

    2016-09-07

    Doxorubicin (Dox, Adriamycin) has been widely used in breast cancer treatment. But its severe cardio-toxic side effects limited the clinical use. Dox treatment can induce DNA damage and other accompanying effects in cancer cells, and subsequently activates nuclear factor κB (NF-κB) pathway which has a strong pro-survival role in different types of malignancy. We hypothesize that blocking NF-κB pathway may sensitize breast cancer cells to Dox chemotherapy. TGFβ-activated kinase-1 (TAK1) is a key intracellular molecule participating in genotoxic stresses-induced NF-κB activation. Targeting TAK1 as a strategy to enhance cancer treatment efficacy has been studied in several malignancies. We showed that NG25, a synthesized TAK1 inhibitor, greatly enhanced Dox treatment efficacy in a panel of breast cancer cell lines. In this pre-clinical study, we found that NG25 partially blocked Dox-induced p38 phosphorylation and IκBα degradation and enhanced Dox-induced cytotoxic effects and apoptosis in all breast cancer cell lines tested. Taken together, we provided clear evidence that NG25 sensitizes the breast cancer cells to Dox treatment in vitro. This combination may be an effective and feasible therapeutic option maximizing Dox efficacy and meanwhile minimizing Dox side effects in treating breast cancer.

  10. The Possible Role of Nitric Oxide and Oxidative Stress in the Enhanced Apoptosis of Cardiac Cells in Cirrhotic Rats

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    Hamed Shafaroodi

    2017-02-01

    Full Text Available  Cirrhosis has been related with hyperdynamic circulation, manifesting as increased cardiac output and decreased systemic vascular resistance. In the present study we examined the cirrhosis outcome on apoptosis of rat hearts. We also tried to explore the role of nitric oxide (NO and oxidative stress in the probable changed apoptosis of cirrhotic hearts. Twenty eight days after ligation of bile duct, heart tissues were tested for apoptosis. The extent of malondialdehyde (MDA, and the activities of catalase (CAT, glutathione peroxidase (GSHPx and superoxide dismutase (SOD have been calculated in heart tissues. The cirrhotic hearts exhibited structural defects and greater apoptosis. Chronic treatment of cirrhotic rats with L-NAME, a non-selective inhibitor of NO synthase, inhibited heart structural defects and reduced apoptosis of hearts. We also showed that cirrhotic rat hearts had an enhanced level of MDA and reduced activities of CAT, GSHPx and SOD. When the animals were treated by L-NAME chronically, the MDA level reduced and activities of CAT, GSHPx and SOD augmented in cirrhotic heart. In conclusion, increased apoptosis of cirrhotic hearts probably happen due to NO overproduction and increased oxidative stress in hearts of cirrhotic rats.

  11. The Possible Role of Nitric Oxide and Oxidative Stress in the Enhanced Apoptosis of Cardiac Cells in Cirrhotic Rats.

    Science.gov (United States)

    Shafaroodi, Hamed; Hashemi, Mehrdad; Sharif, Zahra Nadia; Moezi, Leila; Janahmadi, Zeinab; Dehpour, Ahmad Reza

    2017-01-01

     Cirrhosis has been related with hyperdynamic circulation, manifesting as increased cardiac output and decreased systemic vascular resistance. In the present study we examined the cirrhosis outcome on apoptosis of rat hearts. We also tried to explore the role of nitric oxide (NO) and oxidative stress in the probable changed apoptosis of cirrhotic hearts. Twenty eight days after ligation of bile duct, heart tissues were tested for apoptosis. The extent of malondialdehyde (MDA), and the activities of catalase (CAT), glutathione peroxidase (GSHPx) and superoxide dismutase (SOD) have been calculated in heart tissues. The cirrhotic hearts exhibited structural defects and greater apoptosis. Chronic treatment of cirrhotic rats with L-NAME, a non-selective inhibitor of NO synthase, inhibited heart structural defects and reduced apoptosis of hearts. We also showed that cirrhotic rat hearts had an enhanced level of MDA and reduced activities of CAT, GSHPx and SOD. When the animals were treated by L-NAME chronically, the MDA level reduced and activities of CAT, GSHPx and SOD augmented in cirrhotic heart. In conclusion, increased apoptosis of cirrhotic hearts probably happen due to NO overproduction and increased oxidative stress in hearts of cirrhotic rats.

  12. Phosphoinositide 3-kinase accelerates postoperative tumor growth by inhibiting apoptosis and enhancing resistance to chemotherapy-induced apoptosis. Novel role for an old enemy.

    LENUS (Irish Health Repository)

    Coffey, J Calvin

    2012-02-03

    Tumor removal remains the principal treatment modality in the management of solid tumors. The process of tumor removal may potentiate the resurgent growth of residual neoplastic tissue. Herein, we describe a novel murine model in which flank tumor cytoreduction is followed by accelerated local tumor recurrence. This model held for primary and recurrent tumors generated using a panel of human and murine (LS174T, DU145, SW480, SW640, and 3LL) cell lines and replicated accelerated tumor growth following excisional surgery. In investigating this further, epithelial cells were purified from LS174T primary and corresponding recurrent tumors for comparison. Baseline as well as tumor necrosis factor apoptosis-inducing ligand (TRAIL)-induced apoptosis were significantly reduced in recurrent tumor epithelia. Primary and recurrent tumor gene expression profiles were then compared. This identified an increase and reduction in the expression of p110gamma and p85alpha class Ia phosphoinositide 3-kinase (PI3K) subunits in recurrent tumor epithelia. These changes were further confirmed at the protein level. The targeting of PI3K ex vivo, using LY294002, restored sensitivity to TRAIL in recurrent tumor epithelia. In vivo, adjuvant LY294002 prolonged survival and significantly attenuated recurrent tumor growth by greatly enhancing apoptosis levels. Hence, PI3K plays a role in generating the antiapoptotic and chemoresistant phenotype associated with accelerated local tumor recurrence.

  13. Microemulsion-based synergistic dual-drug codelivery system for enhanced apoptosis of tumor cells.

    Science.gov (United States)

    Qu, Ding; Ma, Yihua; Sun, Wenjie; Chen, Yan; Zhou, Jing; Liu, Congyan; Huang, Mengmeng

    2015-01-01

    A microemulsion-based synergistic dual-drug codelivery system was developed for enhanced cell apoptosis by transporting coix seed oil and etoposide into A549 (human lung carcinoma) cells simultaneously. Results obtained by dynamic light scattering showed that an etoposide (VP16)-loaded coix seed oil microemulsion (EC-ME) delivery system had a small size around 35 nm, a narrow polydispersity index, and a slightly negative surface charge. The encapsulating efficiency and total drug loading rate were 97.01% and 45.48%, respectively, by high-performance liquid chromatography. The release profiles at various pH values showed an obvious pH-responsive difference, with the accumulated amount of VP16 released at pH 4.5 (and pH 5.5) being 2.7-fold higher relative to that at pH 7.4. Morphologic alteration (particle swelling) associated with a mildly acidic pH environment was found on transmission electron microscopy. In the cell study, the EC-ME system showed a significantly greater antiproliferative effect toward A549 cells in comparison with free VP16 and the mixture of VP16 and coix seed oil. The half-maximal inhibitory concentration of the EC-ME system was 3.9-fold and 10.4-fold lower relative to that of free VP16 and a mixture of VP16 and coix seed oil, respectively. Moreover, fluorescein isothiocyanate and VP16 (the green fluorescent probe and entrapped drug, respectively) were efficiently internalized into the cells by means of coix seed oil microemulsion through intuitive observation and quantitative measurement. Importantly, an EC-ME system containing 20 μg/mL of VP16 showed a 3.3-fold and 3.5-fold improvement in induction of cell apoptosis compared with the VP-16-loaded microemulsion and free VP16, respectively. The EC-ME combination strategy holds promise as an efficient drug delivery system for induction of apoptosis and treatment of lung cancer.

  14. Curcumin enhances recovery of pancreatic islets from cellular stress induced inflammation and apoptosis in diabetic rats

    Energy Technology Data Exchange (ETDEWEB)

    Rashid, Kahkashan; Sil, Parames C., E-mail: parames@jcbose.ac.in

    2015-02-01

    The phytochemical, curcumin, has been reported to play many beneficial roles. However, under diabetic conditions, the detail mechanism of its beneficial action in the glucose homeostasis regulatory organ, pancreas, is poorly understood. The present study has been designed and carried out to explore the role of curcumin in the pancreatic tissue of STZ induced and cellular stress mediated diabetes in eight weeks old male Wistar rats. Diabetes was induced with a single intraperitoneal dose of STZ (65 mg/kg body weight). Post to diabetes induction, animals were treated with curcumin at a dose of 100 mg/kg body weight for eight weeks. Underlying molecular and cellular mechanism was determined using various biochemical assays, DNA fragmentation, FACS, histology, immunoblotting and ELISA. Treatment with curcumin reduced blood glucose level, increased plasma insulin and mitigated oxidative stress related markers. In vivo and in vitro experimental results revealed increased levels of proinflammatory cytokines (TNF-α, IL1-β and IFN-γ), reduced level of cellular defense proteins (Nrf-2 and HO-1) and glucose transporter (GLUT-2) along with enhanced levels of signaling molecules of ER stress dependent and independent apoptosis (cleaved Caspase-12/9/8/3) in STZ administered group. Treatment with curcumin ameliorated all the adverse changes and helps the organ back to its normal physiology. Results suggest that curcumin protects pancreatic beta-cells by attenuating inflammatory responses, and inhibiting ER/mitochondrial dependent and independent pathways of apoptosis and crosstalk between them. This uniqueness and absence of any detectable adverse effect proposes the possibility of using this molecule as an effective protector in the cellular stress mediated diabetes mellitus. - Highlights: • STZ induced cellular stress plays a vital role in pancreatic dysfunction. • Cellular stress causes inflammation, pancreatic islet cell death and diabetes. • Deregulation of Nrf-2

  15. Enhanced Macrophage M1 Polarization and Resistance to Apoptosis Enable Resistance to Plague.

    Science.gov (United States)

    Pachulec, Emilia; Abdelwahed Bagga, Rym Ben; Chevallier, Lucie; O'Donnell, Hope; Guillas, Chloé; Jaubert, Jean; Montagutelli, Xavier; Carniel, Elisabeth; Demeure, Christian E

    2017-09-15

    Susceptibility to infection is in part genetically driven, and C57BL/6 mice resist various pathogens through the proinflammatory response of their M1 macrophages (MPs). However, they are susceptible to plague. It has been reported elsewhere that Mus spretus SEG mice resist plague and develop an immune response characterized by a strong recruitment of MPs. The responses of C57BL/6 and SEG MPs exposed to Yersinia pestis in vitro were examined. SEG MPs exhibit a stronger bactericidal activity with higher nitric oxide production, a more proinflammatory polarized cytokine response, and a higher resistance to Y. pestis-induced apoptosis. This response was not specific to Y. pestis and involved a reduced sensitivity to M2 polarization/signal transducer and activator of transcription 6 activation and inhibition of caspase 8. The enhanced M1 profile was inducible in C57BL/6 MPs in vitro, and when transferred to susceptible C57BL/6 mice, these MPs significantly increased survival of bubonic plague. MPs can develop an enhanced functional profile beyond the prototypic M1, characterized by an even more potent proinflammatory response coordinated with resistance to killing. This programming plays a key role in the plague-resistance phenotype and may be similarly significant in other highly lethal infections, suggesting that orienting the MP response may represent a new therapeutic approach.

  16. Berberine promotes antiproliferative effects of epirubicin in T24 bladder cancer cells by enhancing apoptosis and cell cycle arrest
.

    Science.gov (United States)

    Zhuo, Yumin; Chen, Qibiao; Chen, Bo; Zhan, Xiongyu; Qin, Xiaoping; Huang, Jun; Lv, Xiuxiu

    2017-01-01

    The present study was aimed to observe the effect of berberine (Ber) on epirubicin (EPI)-induced growth inhibition, apoptosis, and cell cycle arrest in T24 bladder cancer cells. The cancer cells were exposed to EPI, with or without different concentrations of Ber. The viability of the cancer cells was measured by cell counting Kit-8, the apoptosis was determined by Hoechst 33258 staining and the expression of cleaved caspase-3, cleaved caspase-9, Bcl-2, Bax, and P53 proteins were detected by Western blot assay. In addition, cell cycle arrest and the production of reactive oxygen species (ROS) were also measured. We found that Ber enhanced the inhibitory effect of EPI on the viability of T24 cells and promoted EPI-induced cell cycle arrest at G0/G1 and apoptosis in T24 cells. EPI increased the expression of cleaved caspase-3, cleaved caspase-9, Bax, P53, and P21 proteins, all of which were enhanced by treatment with Ber. In contrast, Ber exposure further decreased the expression of Bcl-2 in EPI-treated T24 cells. Furthermore, we also demonstrated that Ber significantly increased ROS production in EPI-treated T24 cells. These data indicate that Ber enhances the antiproliferative effects of EPI in bladder cancer cells by promoting apoptosis and cell cycle arrest.
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  17. Glucose 6-phosphate dehydrogenase deficiency enhances germ cell apoptosis and causes defective embryogenesis in Caenorhabditis elegans

    Science.gov (United States)

    Yang, H-C; Chen, T-L; Wu, Y-H; Cheng, K-P; Lin, Y-H; Cheng, M-L; Ho, H-Y; Lo, S J; Chiu, D T-Y

    2013-01-01

    Glucose 6-phosphate dehydrogenase (G6PD) deficiency, known as favism, is classically manifested by hemolytic anemia in human. More recently, it has been shown that mild G6PD deficiency moderately affects cardiac function, whereas severe G6PD deficiency leads to embryonic lethality in mice. How G6PD deficiency affects organisms has not been fully elucidated due to the lack of a suitable animal model. In this study, G6PD-deficient Caenorhabditis elegans was established by RNA interference (RNAi) knockdown to delineate the role of G6PD in animal physiology. Upon G6PD RNAi knockdown, G6PD activity was significantly hampered in C. elegans in parallel with increased oxidative stress and DNA oxidative damage. Phenotypically, G6PD-knockdown enhanced germ cell apoptosis (2-fold increase), reduced egg production (65% of mock), and hatching (10% of mock). To determine whether oxidative stress is associated with G6PD knockdown-induced reproduction defects, C. elegans was challenged with a short-term hydrogen peroxide (H2O2). The early phase egg production of both mock and G6PD-knockdown C. elegans were significantly affected by H2O2. However, H2O2-induced germ cell apoptosis was more dramatic in mock than that in G6PD-deficient C. elegans. To investigate the signaling pathways involved in defective oogenesis and embryogenesis caused by G6PD knockdown, mutants of p53 and mitogen-activated protein kinase (MAPK) pathways were examined. Despite the upregulation of CEP-1 (p53), cep-1 mutation did not affect egg production and hatching in G6PD-deficient C. elegans. Neither pmk-1 nor mek-1 mutation significantly affected egg production, whereas sek-1 mutation further decreased egg production in G6PD-deficient C. elegans. Intriguingly, loss of function of sek-1 or mek-1 dramatically rescued defective hatching (8.3- and 9.6-fold increase, respectively) induced by G6PD knockdown. Taken together, these findings show that G6PD knockdown reduces egg production and hatching in C. elegans

  18. 2-O-Methylmagnolol upregulates the long non-coding RNA, GAS5, and enhances apoptosis in skin cancer cells.

    Science.gov (United States)

    Wang, Tong-Hong; Chan, Chieh-Wen; Fang, Jia-You; Shih, Ya-Min; Liu, Yi-Wen; Wang, Tzu-Chien V; Chen, Chi-Yuan

    2017-03-02

    Magnolol, a hydroxylated biphenol compound isolated from the bark of Magnolia officinalis, has been shown to exhibit anti-proliferative effect in various cancer cells, including skin cancer cells. Methoxylation of magnolol appears to improve its anti-inflammatory activity, yet the effect of this modification on the agent's antitumor activity remains unknown. In this work, we report that 2-O-methylmagnolol (MM1) displays improved antitumor activity against skin cancer cells compared to magnolol both in vitro and in vivo. The increased antitumor activity of MM1 appears to correlate with its increased ability to induce apoptosis. DNA microarray and network pathway analyses suggest that MM1 affects certain key factors involved in regulating apoptosis and programmed cell death. Interestingly, the level of the long non-coding (lnc) RNA of growth arrest-specific 5 (GAS5) was increased in MM1-treated cells, and inhibition of lncRNA GAS5 inhibited MM1-induced apoptosis. Conversely, overexpression of lncRNA GAS5 inhibited cell proliferation and promoted cell apoptosis in skin cancer cells. The expression of lncRNA GAS5 in the skin cancer tissues was found to be lower than that in the adjacent normal tissues in a majority of patients. Taken together, our findings suggest that MM1 has improved antitumor activity in skin cancer cells, and that this is due, at least in part, to the upregulation of lncRNA GAS5 and the enhancement of apoptosis.

  19. Stattic Enhances Radiosensitivity and Reduces Radio-Induced Migration and Invasion in HCC Cell Lines through an Apoptosis Pathway

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    Gang Xu

    2017-01-01

    Full Text Available Purpose. Signal transducer and activator of transcription factor 3 (STAT3 is involved in tumorigenesis, development, and radioresistance of many solid tumors. The aim of this study is to investigate the effects of stattic (an inhibitor of STAT3 on the radiosensitivity and radio-induced migration and invasion ability in hepatocellular carcinoma (HCC cell lines. Methods. HCC cells were treated with stattic, and cell survival rate was analyzed through CCK-8 assay. Radiosensitivity was evaluated using cloning formation analysis; STAT3, p-STAT3, and apoptosis related proteins were detected by western blot. Radio-induced migration and invasion ability in HCC cells were analyzed by wound-healing assay and transwell test. Results. Stattic inhibits the expression of p-STAT3 and reduces cell survival in a dose-dependent manner in HCC cell lines, and the IC50 values for Hep G2, Bel-7402, and SMMC-7721 are 2.94 μM, 2.5 μM, and 5.1 μM, respectively. Cloning formation analysis shows that stattic enhances the radiosensitivity of HCC cells. Wound-healing assay and transwell test show that stattic inhibits radio-induced migration and invasion. Further study indicates that stattic promotes radio-induce apoptosis through regulating the expression of apoptosis related proteins in HCC cells. Conclusion. Stattic enhances radiosensitivity and reduces radio-induced migration and invasion ability in HCC cells probably through apoptosis pathway.

  20. Propofol enhances the cisplatin-induced apoptosis on cervical cancer cells via EGFR/JAK2/STAT3 pathway.

    Science.gov (United States)

    Li, Haoran; Lu, Yan; Pang, Yangyang; Li, Mengjiao; Cheng, Xi; Chen, Jiawei

    2017-02-01

    The main purpose of this study was to evaluate propofol and its combined effect with cisplatin on apoptosis of cervical cancer cells and molecular mechanisms of this phenomenon. The effects of propofol and cisplatin on cell viability and apoptosis were detected by cell counting kit-8 (CCK-8) assay, colony formation assay and flow cytometry assay. Besides, protein expression of EGFR/JAK2/STAT3 pathway was determined by western blot. STAT3 was over-expressed in cervical cancer cells by STAT3 cDNA. Expression of EGFR and STAT3 protein of human tissues was evaluated by immunohistochemistry (IHC) assay. In this study, we found that not only propofol alone could inhibit cervical cancer cells viability but also could increase the inhibitory effect of cisplatin on cervical cancer cells growth. Meanwhile, propofol sensitized cervical cancer cells to cisplatin-induced apoptosis but not affected normal cervical cells. In genetic level, propofol could enhance the anti-tumor effect of cisplatin through EGFR/JAK2/STAT3 pathway. Further studies indicated that overexpression of EGFR and STAT3 is related to poor prognoses in cervical cancer patients, which contributed to confirm the clinical role of combined application of propofol and cisplatin. Propofol enhances the cisplatin-induced cell apoptosis cervical cancer cells via EGFR/JAK2/STAT3 pathway and may be developed as a potential therapeutic agent to treat cervical cancer. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  1. Enhancement of hyperthermia-induced apoptosis by 5Z-7-oxozeaenol, a TAK1 inhibitor, in Molt-4 cells.

    Science.gov (United States)

    Li, Peng; Zhao, Qing-Li; Jawaid, Paras; Rehman, Mati Ur; Ahmed, Kanwal; Sakurai, Hiroaki; Kondo, Takashi

    2017-01-22

    Transforming growth factor-β-activated kinase1 (TAK1) plays an anti-apoptotic role in response to multiple stresses. TAK1 inhibitor, 5Z-7-oxozeaenol (OZ) has been studied for its apoptotic effects. However, the combined effect of OZ with physical stresses remains to be elusive. Therefore, in this study we focussed to determine the combined effects of OZ with hyperthermia (HT) using Molt-4 cell line. Molt-4 cells were pre-treated with OZ for 1 h followed by heat exposure (44 °C, 10 min) and harvested 24 h after incubation at 37 °C, apoptosis was measured by Annexin V-FITC/PI double staining assay using flow cytometry and cell growth was observed by cell counting assay. Further mechanism involved in the combination was investigated by measuring mitochondrial membrane potential (MMP), intracellular ROS generation, expression of apoptosis related protein, intracellular calcium ion level and Fas activity. Combination of OZ with HT significantly enhances MMP loss and superoxide generation. Furthermore, OZ pre-treatment promotes caspase-8 cleavage, Fas externalisation, caspase 3 activity and intracellular calcium ion levels. OZ pre-treatment decreased the expression of HT-induced Bcl-2 and increased the expression of pro-apoptotic Bax, while markedly suppressed the phosphorylation of JNK and p38. In addition, increased expression of CHOP following combined treatment indicates that ER stress may also involve in the enhancement of HT-induced apoptosis. Our data showed for the first time that OZ sensitizes Molt-4 cells to HT-induced apoptosis via extrinsic and intrinsic apoptotic pathways. Furthermore, ROS and ER stress may also play role in the enhancement of HT-induced apoptosis by OZ.

  2. Aggregatibacter actinomycetemcomitans infection enhances apoptosis in vivo through a caspase-3-dependent mechanism in experimental periodontitis.

    Science.gov (United States)

    Kang, Jun; de Brito Bezerra, Beatriz; Pacios, Sandra; Andriankaja, Oelisoa; Li, Yu; Tsiagbe, Vincent; Schreiner, Helen; Fine, Daniel H; Graves, Dana T

    2012-06-01

    The purpose of this study was to test the hypothesis that diabetes aggravates periodontal destruction induced by Aggregatibacter actinomycetemcomitans infection. Thirty-eight diabetic and 33 normal rats were inoculated with A. actinomycetemcomitans and euthanized at baseline and at 4, 5, and 6 weeks after inoculation. Bone loss and the infiltration of polymorphonuclear leukocytes (PMNs) in gingival epithelium were measured in hematoxylin-eosin-stained sections. The induction of tumor necrosis factor alpha (TNF-α) was evaluated by immunohistochemistry and of apoptotic cells by a TUNEL (terminal deoxynucleotidyltransferase-mediated dUTP-biotin nick end labeling) assay. After A. actinomycetemcomitans infection, the bone loss in diabetic rats was 1.7-fold and the PMN infiltration 1.6-fold higher than in normoglycemic rats (P infection in gingival epithelium and connective tissue (P periodontal destruction in rats by significantly increasing the inflammatory response, leading to increased bone loss and enhancing apoptosis of gingival epithelial and connective tissue cells through a caspase-3-dependent mechanism. Antibiotics had a more pronounced effect on many of these parameters in diabetic than in normoglycemic rats, suggesting a deficiency in the capacity of diabetic animals to resist infection.

  3. Targeting catalase but not peroxiredoxins enhances arsenic trioxide-induced apoptosis in K562 cells.

    Directory of Open Access Journals (Sweden)

    Li-Li Song

    Full Text Available Despite considerable efficacy of arsenic trioxide (As2O3 in acute promyelocytic leukemia (APL treatment, other non-APL leukemias, such as chronic myeloid leukemia (CML, are less sensitive to As2O3 treatment. However, the underlying mechanism is not well understood. Here we show that relative As2O3-resistant K562 cells have significantly lower ROS levels than As2O3-sensitive NB4 cells. We compared the expression of several antioxidant enzymes in these two cell lines and found that peroxiredoxin 1/2/6 and catalase are expressed at high levels in K562 cells. We further investigated the possible role of peroxirdoxin 1/2/6 and catalase in determining the cellular sensitivity to As2O3. Interestingly, knockdown of peroxiredoxin 1/2/6 did not increase the susceptibility of K562 cells to As2O3. On the contrary, knockdown of catalase markedly enhanced As2O3-induced apoptosis. In addition, we provide evidence that overexpression of BCR/ABL cannot increase the expression of PRDX 1/2/6 and catalase. The current study reveals that the functional role of antioxidant enzymes is cellular context and treatment agents dependent; targeting catalase may represent a novel strategy to improve the efficacy of As2O3 in CML treatment.

  4. Enhanced proliferation and decreased apoptosis in lung lavage cells of sarcoidosis patients.

    Science.gov (United States)

    Petzmann, Susanna; Maercker, Christian; Markert, Eva; Kern, Izidor; Osolnik, Katharina; Pohl, Wolfgang; Popper, Helmut H

    2006-10-01

    Sarcoidosis is a systemic autoimmune disease where an inflammatory reaction involving alveolar macrophages, T-helper lymphocytes, and epitheloid cells is mounted against unknown antigens. A genetic predisposition for sarcoidosis is supposed by studies in twins, by geographical and racial distribution. In the current investigation we compared the expression patterns between slow onset and acute sarcodosis using a whole-genome cDNA array. Bronchoalveolar lavage was performed in six patients with slow onset sarcoidosis and four patients with acute sarcoidosis (Löfgren's disease) and obtained cells were used for gene expression profiling. The results were confirmed by RT- and Taqman-PCR. In addition, protein expression was examined on paraffin sections of sarcoid granulomas by immunohistochemistry. In T-helper lymphocytes and alveolar macrophages we found an upregulation of genes belonging to the phosphoinositol-3-kinase/v-akt murine thymoma viral oncogene homolog/signal transducer and activator of transcription 3 pathway, as well as a downregulation of genes of the extrinsic and intrinsic apoptotic signaling cascades. In addition an upregulation of the genes encoding fatty acid binding protein 4 and 5, as well as peroxisome proliferative activated receptor delta in Löfgren's disease was detected. Differences in gene expression between slow onset sarcoidosis and Löfgren's syndrome were found mainly within genes of the major histocompatibility complex. In sarcoidosis enhanced cell proliferation and decreased apoptosis result in accumulation and prolonged survival of antigen-primed T-helper lymphocytes and activated macrophages. This is enhanced in Löfgren's disease, probably by hyper-stimulation via the peroxisome proliferation signaling, providing a larger pool of antigen-primed immune cells.

  5. MicroRNA-661 Enhances TRAIL or STS Induced Osteosarcoma Cell Apoptosis by Modulating the Expression of Cytochrome c1

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    Lin Fan

    2017-04-01

    Full Text Available Aim: Osteosarcoma (OS is an aggressive bone malignancy that affects rapidly growing bones and is associated with a poor prognosis. Our previous study showed that cytochrome c1 (CYC1, a subunit of the cytochrome bc1 complex (complex III of the mitochondrial electron chain, is overexpressed in human OS tissues and cell lines and its silencing induces apoptosis in vitro and inhibits tumor growth in vivo. Here, we investigated the mechanism underlying the modulation of CYC1 expression in OS and its role in the resistance of OS to apoptosis. Methods: qRT-PCR, luciferase reporter assay, western blotting, fow cytometry, and animal experiments were performed in this study. Results: MicroRNA (miR-661 was identified as a downregulated miRNA in OS tissues and cells and shown to directly target CYC1. Ectopically expressed miR-661 inhibited OS cell growth, promoted apoptosis, and reduced the activity of mitochondrial complex III. miR-661 overexpression enhanced TRAIL or STS induced apoptosis and promoted the release of cytochrome c into the cytosol, which induced caspase-9 activation, and these effects were abolished by a caspase-3 inhibitor. Overexpression of CYC1 rescued the effects of miR-661 on sensitizing OS cells to TRAIL or STS induced apoptosis, indicating that the antitumor effect of miR-661 is mediated by the downregulation of CYC1. In vivo, miR-661 overexpression sensitized tumors to TRAIL or STS induced apoptosis in a xenograft mouse model, and these effects were attenuated by co-expression of CYC1. Conclusion: Taken together, our results indicate that miR-661 plays a tumor suppressor role in OS mediated by the downregulation of CYC1, suggesting a potential mechanism underlying cell death resistance in OS.

  6. Promyelocytic leukemia protein enhances apoptosis of gastric cancer cells through Yes-associated protein.

    Science.gov (United States)

    Xu, Zhipeng; Chen, Jiamin; Shao, Liming; Ma, Wangqian; Xu, Dingting

    2015-09-01

    It has been shown that Yes-associated protein (YAP) acts as a transcriptional co-activator to regulate p73-dependent apoptosis in response to DNA damage in some cell types, and promyelocytic leukemia (PML) protein is involved in the regulation loop through stabilization of YAP through sumoylation. Although YAP has been shown to be significantly upregulated in gastric cancer, whether the YAP/PML/p73 regulation loop also functions in gastric cancer is unknown. Here, we show significantly higher levels of YAP and significantly lower levels of PML in the gastric cancer specimen. Overexpression of YAP in gastric cancer cells significantly increased cell growth, but did not affect apoptosis. However, overexpression of PML in gastric cancer cells significantly increased cell apoptosis, resulting in decreases in cell growth, which seemed to require the presence of YAP. The effect of PML on apoptosis appeared to be conducted through p73-mediated modulation of apoptosis-associated genes, Bcl-2, Bak, and caspase9. Thus, our study suggests the presence of a YAP/PML/p73 regulatory loop in gastric cancer, and highlights PML as a promising tumor suppressor in gastric cancer through YAP-coordinated cancer cell apoptosis.

  7. An enhanced bioluminescence-based Annexin V probe for apoptosis detection in vitro and in vivo.

    Science.gov (United States)

    Head, Trajen; Dau, Peter; Duffort, Stephanie; Daftarian, Pirouz; Joshi, Pratibha M; Vazquez-Padron, Roberto; Deo, Sapna K; Daunert, Sylvia

    2017-05-25

    The process of controlled cellular death known as apoptosis has an important central role not only in normal homeostatic maintenance of tissues, but also in numerous diseases such as cancer, neurodegenerative, autoimmune, and cardiovascular diseases. As a result, new technologies with the capability to selectively detect apoptotic cells represent a central focus of research for the study of these conditions. We have developed a new biosensor for the detection of apoptotic cells, incorporating the targeted selectivity for apoptotic cells from Annexin V with the sensitivity of bioluminescence signal generation from a serum-stable mutant of Renilla luciferase (RLuc8). Our data presents a complete characterization of the structural and biochemical properties of this new Annexin-Renilla fusion protein (ArFP) construct, as well as a validation of its ability to detect apoptosis in vitro. Moreover, this work represents the first report of a bioluminescent Annexin V apoptosis sensor utilized in vivo. With this new construct, we examine apoptosis within disease-relevant animal models of surgery-induced ischemia/reperfusion, corneal injury, and retinal cell death as a model of age-related macular degeneration. In each of these experiments, we demonstrate successful application of the ArFP construct for detection and bioluminescence imaging of apoptosis within each disease or treatment model. ArFP represents an important new tool in the continuously growing kit of technologies for apoptosis detection, and our results from both in vitro and in vivo experiments suggest a diverse range of potential clinically relevant applications including cancer therapeutic screening and efficacy analysis, atherosclerosis and cardiovascular disease detection, and the monitoring of any number of other conditions in which apoptosis has a central role.

  8. The long non-coding RNA HOTAIR enhances pancreatic cancer resistance to TNF-related apoptosis-inducing ligand.

    Science.gov (United States)

    Yang, Shan-Zhong; Xu, Fei; Zhou, Tong; Zhao, Xinyang; McDonald, Jay M; Chen, Yabing

    2017-06-23

    Pancreatic cancer is a malignant neoplasm with a high mortality rate. Therapeutic agents that activate TNF-related apoptosis-inducing ligand (TRAIL)-induced apoptosis have shown promising efficacy, but many pancreatic cancers are resistant to TRAIL therapy. Epigenetic regulation plays important roles in tumor pathogenesis and resistance, and a recent study indicated that the long non-coding RNA HOX transcript antisense RNA (HOTAIR) is overexpressed in pancreatic cancer. However, the role of HOTAIR in pancreatic cancer resistance to anticancer agents is unknown. The present study determined the role of HOTAIR in pancreatic cancer TRAIL resistance and investigated the underlying molecular mechanisms. We observed that TRAIL-resistant pancreatic cancer cells had higher levels of HOTAIR expression, whereas TRAIL-sensitive pancreatic cancer cells had lower HOTAIR levels. Overexpressing HOTAIR in TRAIL-sensitive cells attenuated TRAIL-induced apoptosis, and shRNA-mediated HOTAIR knockdown in TRAIL-resistant PANC-1 cells sensitized them to TRAIL-induced apoptosis. These results support a causative effect of HOTAIR on TRAIL sensitivity. Mechanistically, we found that increased HOTAIR expression inhibited the expression of the TRAIL receptor death receptor 5 (DR5), whereas HOTAIR knockdown increased DR5 expression. We further demonstrated that HOTAIR regulates DR5 expression via the epigenetic regulator enhancer of zeste homolog 2 (EZH2) and that EZH2 controls histone H3 lysine 27 trimethylation on the DR5 gene. Taken together, these results demonstrate that high HOTAIR levels increase the resistance of pancreatic cancer cells to TRAIL-induced apoptosis via epigenetic regulation of DR5 expression. Our study therefore supports the notion that targeting HOTAIR function may represent a strategy to overcome TRAIL resistance in pancreatic cancer. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  9. Heme oxygenase-1 enhances autophagy in podocytes as a protective mechanism against high glucose-induced apoptosis

    Energy Technology Data Exchange (ETDEWEB)

    Dong, Chenglong [Department of Endocrinology, The Second Affiliated Hospital of Nanjing Medical University, Nanjing (China); Zheng, Haining [Department of Hyperbaric Oxygen, Nanjing General Hospital of Nanjing Military Command, Nanjing (China); Huang, Shanshan; You, Na; Xu, Jiarong; Ye, Xiaolong; Zhu, Qun; Feng, Yamin; You, Qiang; Miao, Heng [Department of Endocrinology, The Second Affiliated Hospital of Nanjing Medical University, Nanjing (China); Ding, Dafa, E-mail: dingdafa2004@aliyun.com [Department of Endocrinology, The Second Affiliated Hospital of Nanjing Medical University, Nanjing (China); Lu, Yibing, E-mail: luyibing2004@126.com [Department of Endocrinology, The Second Affiliated Hospital of Nanjing Medical University, Nanjing (China)

    2015-10-01

    Injury and loss of podocytes play vital roles in diabetic nephropathy progression. Emerging evidence suggests autophagy, which is induced by multiple stressors including hyperglycemia, plays a protective role. Meanwhile, heme oxygenase-1 (HO-1) possesses powerful anti-apoptotic properties. Therefore, we investigated the impact of autophagy on podocyte apoptosis under diabetic conditions and its association with HO-1. Mouse podocytes were cultured in vitro; apoptosis was detected by flow cytometry. Transmission electron microscopy and biochemical autophagic flux assays were used to measure the autophagy markers microtubule-associated protein 1 light chain 3-II (LC3-II) and beclin-1. LC3-II and beclin-1 expression peaked 12–24 h after exposing podocytes to high glucose. Inhibition of autophagy with 3-methyladenine or Beclin-1 siRNAs or Atg 5 siRNAs sensitized cells to apoptosis, suggesting autophagy is a survival mechanism. HO-1 inactivation inhibited autophagy, which aggravated podocyte injury in vitro. Hemin-induced autophagy also protected podocytes from hyperglycemia in vitro and was abrogated by HO-1 siRNA. Adenosine monophosphate-activated protein kinase phosphorylation was higher in hemin-treated and lower in HO-1 siRNA-treated podocytes. Suppression of AMPK activity reversed HO-1-mediated Beclin-1 upregulation and autophagy, indicating HO-1-mediated autophagy is AMPK dependent. These findings suggest HO-1 induction and regulation of autophagy are potential therapeutic targets for diabetic nephropathy. - Highlights: • High glucose leads to increased autophagy in podocytes at an early stage. • The early autophagic response protects against high glucose-induced apoptosis. • Heme oxygenase-1 enhances autophagy and decreases high glucose -mediated apoptosis. • Heme oxygenase-1 induces autophagy through the activation of AMPK.

  10. Potential therapeutic application of gold nanoparticles in B-chronic lymphocytic leukemia (BCLL: enhancing apoptosis

    Directory of Open Access Journals (Sweden)

    Lu Lichun

    2007-05-01

    Full Text Available Abstract B-Chronic Lymphocytic Leukemia (CLL is an incurable disease predominantly characterized by apoptosis resistance. We have previously described a VEGF signaling pathway that generates apoptosis resistance in CLL B cells. We found induction of significantly more apoptosis in CLL B cells by co-culture with an anti-VEGF antibody. To increase the efficacy of these agents in CLL therapy we have focused on the use of gold nanoparticles (GNP. Gold nanoparticles were chosen based on their biocompatibility, very high surface area, ease of characterization and surface functionalization. We attached VEGF antibody (AbVF to the gold nanoparticles and determined their ability to kill CLL B cells. Gold nanoparticles and their nanoconjugates were characterized using UV-Visible spectroscopy (UV-Vis, transmission electron microscopy (TEM, thermogravimetric analysis (TGA and X-ray photoelectron spectroscopy (XPS. All the patient samples studied (N = 7 responded to the gold-AbVF treatment with a dose dependent apoptosis of CLL B cells. The induction of apoptosis with gold-AbVF was significantly higher than the CLL cells exposed to only AbVF or GNP. The gold-AbVF treated cells showed significant down regulation of anti-apoptotic proteins and exhibited PARP cleavage. Gold-AbVF treated and GNP treated cells showed internalization of the nanoparticles in early and late endosomes and in multivesicular bodies. Non-coated gold nanoparticles alone were able to induce some levels of apoptosis in CLL B cells. This paper opens up new opportunities in the treatment of CLL-B using gold nanoparticles and integrates nanoscience with therapy in CLL. In future, potential opportunities exist to harness the optoelectronic properties of gold nanoparticles in the treatment of CLL.

  11. Dysregulated IER3 Expression is Associated with Enhanced Apoptosis in Titin-Based Dilated Cardiomyopathy

    Directory of Open Access Journals (Sweden)

    Qifeng Zhou

    2017-03-01

    Full Text Available Apoptosis (type I programmed cell death of cardiomyocytes is a major process that plays a role in the progression of heart failure. The early response gene IER3 regulates apoptosis in a wide variety of cells and organs. However, its role in heart failure is largely unknown. Here, we investigate the role of IER3 in an inducible heart failure mouse model. Heart failure was induced in a mouse model that imitates a human titin truncation mutation we found in a patient with dilated cardiomyopathy (DCM. Transferase dUTP nick end labeling (TUNEL and ssDNA stainings showed induction of apoptosis in titin-deficient cardiomyocytes during heart failure development, while IER3 response was dysregulated. Chromatin immunoprecipitation and knock-down experiments revealed that IER3 proteins target the promotors of anti-apoptotic genes and act as an anti-apoptotic factor in cardiomyocytes. Its expression is blunted during heart failure development in a titin-deficient mouse model. Targeting the IER3 pathway to reduce cardiac apoptosis might be an effective therapeutic strategy to combat heart failure.

  12. Genistein sensitizes human hepatocellular carcinoma cells to TRAIL-mediated apoptosis by enhancing Bid cleavage.

    Science.gov (United States)

    Jin, Cheng-Yun; Park, Cheol; Moon, Sung-Kwon; Kim, Gi-Young; Kwon, Taeg Kyu; Lee, Su Jae; Kim, Wun-Jae; Choi, Yung Hyun

    2009-09-01

    Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a member of the tumor necrosis factor superfamily, and it has been shown that many human cancer cell lines are refractory to TRAIL-induced cell death. However, the molecular mechanisms underlying resistance are unclear. In this study, we show that TRAIL resistance is reversed in human hepatoma cells by genistein, an isoflavone found in soy products. Synergistic induction of apoptosis in cells treated with genistein plus TRAIL was associated with cleavage of Bid, a proapoptotic BH3-only protein. Silencing of Bid expression reduced decreases in mitochondrial membrane potential and reduced apoptosis in cells treated with genistein and TRAIL, confirming that Bid cleavage is required for the response. Pretreatment with caspase-3 and caspase-8 inhibitors reduced cotreatment-induced apoptosis. However, treatment with TRAIL alone induced caspase-8 activity that was not different than TRAIL plus genistein; both effectively induced Bid cleavage. These data suggest that genistein abolishes resistance to the Bid cleavage of TRAIL, and that genistein does not interfere with signals upstream of Bid in hepatoma cells.

  13. Trolox selectively enhances arsenic-mediated oxidative stress and apoptosis in APL and other malignant cell lines.

    Science.gov (United States)

    Diaz, Zuanel; Colombo, Myrian; Mann, Koren K; Su, Haixiang; Smith, Kamilah N; Bohle, D Scott; Schipper, Hyman M; Miller, Wilson H

    2005-02-01

    Although arsenic trioxide (As(2)O(3)) is an effective therapy in acute promyelocytic leukemia (APL), its use in other malignancies is limited by the toxicity of concentrations required to induce apoptosis in non-APL tumor cells. We looked for agents that would synergize with As(2)O(3) to induce apoptosis in malignant cells, but not in normal cells. We found that trolox (6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid), a widely known antioxidant, enhances As(2)O(3)-mediated apoptosis in APL, myeloma, and breast cancer cells. Treatment with As(2)O(3) and trolox increased intracellular oxidative stress, as evidenced by heme oxygenase-1 (HO-1) protein levels, c-Jun terminal kinase (JNK) activation, and protein and lipid oxidation. The synergistic effects of trolox may be specific to As(2)O(3), as trolox does not add to toxicity induced by other chemotherapeutic drugs. We explored the mechanism of this synergy using electron paramagnetic resonance and observed the formation of trolox radicals when trolox was combined with As(2)O(3), but not with doxorubicin. Importantly, trolox protected nonmalignant cells from As(2)O(3)-mediated cytotoxicity. Our data provide the first evidence that trolox may extend the therapeutic spectrum of As(2)O(3). Furthermore, the combination of As(2)O(3) and trolox shows potential specificity for tumor cells, suggesting it may not increase the toxicity associated with As(2)O(3) monotherapy in vivo.

  14. Spirulina Extract Enhanced a Protective Effect in Type 1 Diabetes by Anti-Apoptosis and Anti-ROS Production

    Science.gov (United States)

    Lee, Jiyeong; Park, Arum; Kim, Mi Jeong; Lim, Hee-Joung; Rha, Young-Ah

    2017-01-01

    Interest in the nutritional value and pharmacological activities of blue-green algae has gradually increased. Spirulina extracts show protective effects against apoptosis and inflammatory damage in various cell types. Here, we investigated the protective effects of extracts from Spirulina maxima in a cytokine-mediated type 1 diabetes model in vitro and in streptozotocin-induced diabetic Wistar rats in vivo. Interleukin-1β and interferon-gamma induced substantial cytotoxicity to RINm5F rat insulinoma cells, increasing nitric oxide (NO) production, nuclear factor-kappa B (NF-κB) activity, the expression of endoplasmic reticulum (ER) stress genes, and activation of mitogen-activated protein kinases and key genes related apoptosis. However, the cytotoxicity of cytokines was significantly attenuated by Spirulina extract, which effectively prevented NO production by inhibiting the synthesis of cytokine-activated NO synthase (iNOS), and apoptosis was suppressed. These results suggest that Spirulina extract might be effective to preserve the viability and function of pancreatic β-cells against cytotoxic conditions. Moreover, diabetic mice orally administered Spirulina extract showed decreased glucose levels, increased insulin, and improvement in liver enzyme markers. The antioxidant effect of Spirulina extract may be helpful in treating type 1 diabetes by enhancing the survival, and reducing or delaying cytokine-mediated β-cells destruction. PMID:29244751

  15. Enhanced apoptosis in retinal pigment epithelium under inflammatory stimuli and oxidative stress

    Science.gov (United States)

    Wang, Yujuan; Shen, Defen; Wang, Vinson M.; Yu, Cheng-Rong; Wang, Ren-Xi; Tuo, Jingsheng; Chan, Chi-Chao

    2012-01-01

    Age-related macular degeneration (AMD) is a neurodegenerative disease that causes irreversible central vision loss in the elderly. Retinal pigment epithelium (RPE) has been found to be a key component in AMD pathogenesis. The Ccl2−/−/Cx3cr1−/− (DKO) mouse on Crb1rd8 background is created as an AMD model, developing AMD-like retinal lesions. Our study aimed to examine RPE apoptosis in DKO mouse and human ARPE-19 cell line. DKO RPE expressed higher apoptotic proteins when compared with age-matched wild type (WT) RPE in physiological conditions. Apoptosis of primary cultured mouse RPE was evaluated under stimulation with lipopolysaccharide for inflammatory stimulation and 2,3,7,8-tetrachlorodibenzo-p-dioxin or H2O2 for oxidative stress. Compared with WT RPE, DKO RPE was more susceptible to Fas ligand (FasL)-mediated apoptosis under both inflammatory and oxidative stress, with less cell viability and higher expression of apoptotic transcripts and proteins. Decreased cell viability was also observed in ARPE-19 cells under each stimulus. Furthermore, we also investigated the anti-apoptotic effects of decoy receptor 3 (DcR3), a decoy receptor for FasL, on ARPE-19 cells under inflammatory and oxidative stress. DcR3 pre-incubated ARPE-19 cells showed decreased apoptosis, with increased cell viability and decreased expression of apoptotic transcripts and proteins under the stimuli. On the contrary, knockdown of DcR3 in ARPE-19 cells showed totally opposite results. Our study demonstrates that FasL-mediated RPE apoptosis may play a pivotal role in AMD pathogenesis. PMID:22911474

  16. Hyperthermia combined with 5-fluorouracil promoted apoptosis and enhanced thermotolerance in human gastric cancer cell line SGC-7901

    Directory of Open Access Journals (Sweden)

    Liu T

    2015-05-01

    Full Text Available Tao Liu,* Yan-Wei Ye,* A-li Zhu, Zhen Yang, Yang Fu, Chong-Qing Wei, Qi Liu, Chun-Lin Zhao, Guo-Jun Wang, Xie-Fu Zhang Department of Gastrointestinal Surgery, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, People’s Republic of China *These authors contributed equally to this work Abstract: This study was designed to investigate the proliferation inhibition and apo­ptosis-promoting effect under hyperthermia and chemotherapy treatment, at cellular level. Human gastric cancer cell line SGC-7901 was cultivated with 5-fluorouracil at different temperatures. Cell proliferation and apoptosis were determined, and expression of Bcl-2 and HSP70 was measured at different treatments. Cell survival rates and inhibition rates in chemotherapy group, thermotherapy group, and thermo-chemotherapy group were drastically lower than the control group (P<0.05. For tumor cells in the thermo-chemotherapy group, survival rates and inhibition rates at three different temperatures were all significantly lower than those in chemotherapy group and thermotherapy group (P<0.05. 5-Fluorouracil induced apoptosis of SGC-7901 cells with a strong temperature dependence, which increased gradually with increase in temperature. At 37°C and 43°C there were significant differences between the thermotherapy group and chemotherapy group and between the thermo-chemotherapy group and thermotherapy group (P<0.01. The expression of Bcl-2 was downregulated and HSP70 was upregulated, with increase in temperature in all groups. Cell apoptosis was not significant at 46°C (P>0.05, which was probably due to thermotolerance caused by HSP70 accumulation. These results suggested that hyperthermia combined with 5-fluorouracil had a synergistic effect in promoting apoptosis and enhancing thermotolerance in gastric cancer cell line SGC-7901. Keywords: gastric cancer, thermotherapy, 5-fluorouracil, Bcl-2, HSP70, thermotolerance

  17. MiR-195 enhances cardiomyocyte apoptosis induced by hypoxia/reoxygenation injury via downregulating c-myb.

    Science.gov (United States)

    Chen, C; Jia, K-Y; Zhang, H-L; Fu, J

    2016-08-01

    In this study, we explored the regulative effect of miR-195 on c-myb expression and also investigated the role of miR-195 and c-myb in cardiomyocyte apoptosis induced by hypoxia/reoxygenation (H/R) injury. QRT-PCR analysis was performed to measure mature miR-195 expression. H9c2 cells were transfected for miR-195 overexpression or knockdown or c-myb overexpression using Lipofectamine 2000. The cells were subjected to H/R treatment and following flow cytometric analysis of active caspase-3 or florescent study of reactive oxygen species (ROS) generation. The binding sites between miR-195 and 3'UTR of MYB mRNA were predicted using TargetScan 7.0. The binding sites were verified using dual luciferase assay and Western blot analysis. MiR-195 is significantly upregulated after H/R treatment in H9c2 cells. H/R injury induced active caspase-3 expression. However, the cells with miR-195 suppression had substantially lower ratio of cells with active caspase-3. MiR-195 can decrease c-myb protein expression. Dual luciferase assay verified two binding sites between miR-195 and 3'UTR of MYB mRNA. C-myb overexpression can suppress mitochondrial superoxide generation and cardiomyocyte apoptosis after H/R. MiR-195 is significantly increased due to H/R and can enhance cardiomyocyte apoptosis. MYB is a target gene of miR-195 in cardiomyocytes. The miR-195-MYB axis is involved in regulation of cardiomyocyte apoptosis induced by H/R.

  18. CD38 enhances the proliferation and inhibits the apoptosis of cervical cancer cells by affecting the mitochondria functions.

    Science.gov (United States)

    Liao, Shan; Xiao, Songshu; Chen, Hongxiang; Zhang, Manying; Chen, Zhifang; Long, Yuehua; Gao, Lu; Zhu, Guangchao; He, Junyu; Peng, Shuping; Xiong, Wei; Zeng, Zhaoyang; Li, Zheng; Zhou, Ming; Li, Xiaoling; Ma, Jian; Wu, Minghua; Xiang, Juanjuan; Li, Guiyuan; Zhou, Yanhong

    2017-10-01

    Cervical cancer is one of the most common malignant tumors in women all over the world. The exact mechanism of occurrence and development of cervical cancer has not been fully elucidated. CD38 is a type II transmembrane glycoprotein, which was found to mediate diverse activities, including signal transduction, cell adhesion, and cyclic ADP-ribose synthesis. Here, we reported that CD38 promoted cell proliferation and inhibited cell apoptosis in cervical cancer cells by affecting the mitochondria functions. We established stable cervical cancer cell lines with CD38 over-expressed. CCK8 assay and colony formation assay indicated that CD38 promoted cervical cancer cell proliferation. Nude mouse tumorigenicity assay showed that CD38 significantly promotes tumor growth in vivo. CD38 also induced S phase accumulation in cell cycle analysis and suppressed cell apoptosis in cervical cancer cells. Meanwhile, flow cytometry analysis of mitochondria functions suggested that CD38 decreased intracellular Ca2+ levels in cervical cancer cells and CD38 was involved in down-regulation of ROS levels and prevented mitochondrial apoptosis in cervical cancer cells. The percentage of cells with loss of mitochondrial membrane potential (Δψm) in CD38-overexpressed cervical cancer cells was less than control groups. Furthermore, we found an up-regulation of MDM2, cyclinA1, CDK4, cyclinD1, NF-kB P65, c-rel, and a downregulation of P53, P21, and P38 by Western blot analysis. These results indicated that CD38 enhanced the proliferation and inhibited the apoptosis of cervical cancer cells by affecting the mitochondria functions. © 2017 Wiley Periodicals, Inc.

  19. Exogenous estradiol enhances apoptosis in regressing post-partum rat corpora lutea possibly mediated by prolactin

    Directory of Open Access Journals (Sweden)

    Telleria Carlos M

    2005-08-01

    Full Text Available Abstract Background In pregnant rats, structural luteal regression takes place after parturition and is associated with cell death by apoptosis. We have recently shown that the hormonal environment is responsible for the fate of the corpora lutea (CL. Changing the levels of circulating hormones in post-partum rats, either by injecting androgen, progesterone, or by allowing dams to suckle, was coupled with a delay in the onset of apoptosis in the CL. The objectives of the present investigation were: i to examine the effect of exogenous estradiol on apoptosis of the rat CL during post-partum luteal regression; and ii to evaluate the post-partum luteal expression of the estrogen receptor (ER genes. Methods In a first experiment, rats after parturition were separated from their pups and injected daily with vehicle or estradiol benzoate for 4 days. On day 4 post-partum, animals were sacrificed, blood samples were taken to determine serum concentrations of hormones, and the ovaries were isolated to study apoptosis in situ. In a second experiment, non-lactating rats after parturition received vehicle, estradiol benzoate or estradiol benzoate plus bromoergocryptine for 4 days, and their CL were isolated and used to study apoptosis ex vivo. In a third experiment, we obtained CL from rats on day 15 of pregnancy and from non-lactating rats on day 4 post-partum, and studied the expression of the messenger RNAs (mRNAs encoding the ERalpha and ERbeta genes. Results Exogenous administration of estradiol benzoate induced an increase in the number of apoptotic cells within the CL on day 4 post-partum when compared with animals receiving vehicle alone. Animals treated with the estrogen had higher serum prolactin and progesterone concentrations, with no changes in serum androstenedione. Administration of bromoergocryptine blocked the increase in serum prolactin and progesterone concentrations, and DNA fragmentation induced by the estrogen treatment. ERalpha and

  20. Programmed cell death-10 enhances proliferation and protects malignant T cells from apoptosis

    DEFF Research Database (Denmark)

    Lauenborg, Britt; Kopp, Katharina; Krejsgaard, Thorbjørn

    2010-01-01

    of cutaneous T-cell lymphoma (Sezary syndrome) patients. PDCD10 is associated with protein phosphatase-2A, a regulator of mitogenesis and apoptosis in malignant T cells. Inhibition of oncogenic signal pathways [Jak3, Notch1, and nuclear factor-¿B (NF-¿B)] partly inhibits the constitutive PDCD10 expression......The programmed cell death-10 (PDCD10; also known as cerebral cavernous malformation-3 or CCM3) gene encodes an evolutionarily conserved protein associated with cell apoptosis. Mutations in PDCD10 result in cerebral cavernous malformations, an important cause of cerebral hemorrhage. PDCD10...... is associated with serine/threonine kinases and phosphatases and modulates the extracellular signal-regulated kinase pathway suggesting a role in the regulation of cellular growth. Here we provide evidence of a constitutive expression of PDCD10 in malignant T cells and cell lines from peripheral blood...

  1. MiR-133b targets antiapoptotic genes and enhances death receptor-induced apoptosis.

    Directory of Open Access Journals (Sweden)

    Juan P Patron

    Full Text Available Despite the importance of microRNAs (miRs for regulation of the delicate balance between cell proliferation and death, evidence for their specific involvement during death receptor (DR-mediated apoptosis is scarce. Transfection with miR-133b rendered resistant HeLa cells sensitive to tumor necrosis factor-alpha (TNFα-induced cell death. Similarly, miR-133b caused exacerbated proapoptotic responses to TNF-related apoptosis-inducing ligand (TRAIL or an activating antibody to Fas/CD95. Comprehensive analysis, encompassing global RNA or protein expression profiling performed by microarray experiments and pulsed stable isotope labeling with amino acids in cell culture (pSILAC, led to the discovery of the antiapoptotic protein Fas apoptosis inhibitory molecule (FAIM as immediate miR-133b target. Moreover, miR-133b impaired the expression of the detoxifying protein glutathione-S-transferase pi (GSTP1. Expression of miR-133b in tumor specimens of prostate cancer patients was significantly downregulated in 75% of the cases, when compared with matched healthy tissue. Furthermore, introduction of synthetic miR-133b into an ex-vivo model of prostate cancer resulted in impaired proliferation and cellular metabolic activity. PC3 cells were also sensitized to apoptotic stimuli after transfection with miR-133b similar to HeLa cells. These data reveal the ability of a single miR to influence major apoptosis pathways, suggesting an essential role for this molecule during cellular transformation, tumorigenesis and tissue homeostasis.

  2. Enhancement of Apoptosis by Titanium Alloy Internal Fixations during Microwave Treatments for Fractures: An Animal Study.

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    Gang Wang

    Full Text Available Microwaves are used in one method of physical therapy and can increase muscle tissue temperature which is useful for improving muscle, tendon and bone injuries. In the study, we sought to determine whether titanium alloy internal fixations influence apoptosis in tissues subjected to microwave treatments at 2,450 MHz and 40 W during the healing of fractures because this issue is not yet fully understood.In this study, titanium alloy internal fixations were used to treat 3.0-mm transverse osteotomies in the middle of New Zealand rabbits' femurs. After the operation, 30-day microwave treatments were applied to the 3.0 mm transverse osteotomies 3 days after the operation. The changes in the temperatures of the muscle tissues in front of the implants or the 3.0 mm transverse osteotomies were measured during the microwave treatments. To characterize the effects of titanium alloy internal fixations on apoptosis in the muscles after microwave treatment, we performed TUNEL assays, fluorescent real-time (quantitative PCR, western blotting analyses, reactive oxygen species (ROS detection and transmission electron microscopy examinations.The temperatures were markedly increased in the animals with the titanium alloy implants. Apoptosis in the muscle cells of the implanted group was significantly more extensive than that in the non-implanted control group at different time points. Transmission electron microscopy examinations of the skeletal muscles of the implanted groups revealed muscular mitochondrial swelling, vacuolization. ROS, Bax and Hsp70 were up-regulated, and Bcl-2 was down-regulated in the implanted group.Our results suggest that titanium alloy internal fixations caused greater muscular tissue cell apoptosis following 2,450 MHz, 40 W microwave treatments in this rabbit femur fracture models.

  3. Inhibition of telomerase using BIBR1532 enhances doxorubicin-induced apoptosis in pre-B acute lymphoblastic leukemia cells.

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    Bashash, Davood; Zareii, Mohadeseh; Safaroghli-Azar, Ava; Omrani, Mir Davood; Ghaffari, Seyed H

    2017-07-01

    Interest into targeting telomerase in cancer has increased by the recent disclosure that elevated telomerase activity is associated with disease recurrence and poor outcome in cancers. In addition, cellular acquisition of unlimited replicative potential, which is closely related to the maintenance of telomeres mostly via the reactivation of telomerase, has been shown to confer loss of sensitivity to a wide range of anti-neoplastic agents. To evaluate whether telomerase inhibition using non-nucleosidic inhibitor of telomerase BIBR1532 could enhance cytotoxic effect of doxorubicin in acute lymphoblastic leukemia, Nalm-6 pre-B ALL cells were subjected to combination treatment and subsequent cell viability, growth kinetics, caspase-3 activity, and transcriptional alteration of p73, p21, FOXO3a, c-Myc, hTERT, and other apoptosis-related target genes were investigated. Combination of BIBR1532 with doxorubicin produced a synergistic anticancer effect probably through induction of p73. Transcription factor p73 not only suppressed the proliferative capacity of the cells through induction of p21-mediated G1 arrest, but also down-regulated the mRNA level of hTERT and c-Myc. Our results also report that BIBR1532 induced a caspase-dependent apoptosis, at least partially, through heightened ROS levels, and noteworthy enhanced the pro-oxidant property of doxorubicin. In harmony, transcriptional repression of survivin could be a probable underlying mechanism for the induction of apoptosis through shifting the ratio of death promoters to death repressors via alteration of Bax and Bcl2 expression. Overall, it seems that combination of BIBR1532 and doxorubicin could be a novel therapeutic strategy for acute lymphoblastic leukemia that may be clinically accessible in the near future.

  4. Equol enhances tamoxifen's anti-tumor activity by induction of caspase-mediated apoptosis in MCF-7 breast cancer cells.

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    Charalambous, Christiana; Pitta, Chara A; Constantinou, Andreas I

    2013-05-15

    Soy phytoestrogens, such as daidzein and its metabolite equol, have been proposed to be responsible for the low breast cancer rate in Asian women. Since the majority of estrogen receptor positive breast cancer patients are treated with tamoxifen, the basic objective of this study is to determine whether equol enhances tamoxifen's anti-tumor effect, and to identify the molecular mechanisms involved. For this purpose, we examined the individual and combined effects of equol and tamoxifen on the estrogen-dependent MCF-7 breast cancer cells using viability assays, annexin-V/PI staining, cell cycle and western blot analysis. We found that equol (>50 μM) and 4-hydroxy-tamoxifen (4-OHT; >100 nM) significantly reduced the MCF-7 cell viability. Furthermore, the combination of equol (100 μM) and 4-OHT (10 μM) induced apoptosis more effectively than each compound alone. Subsequent treatment of MCF-7 cells with the pan-caspase inhibitor Z-VAD-FMK inhibited equol- and 4-OHT-mediated apoptosis, which was accompanied by PARP and α-fodrin cleavage, indicating that apoptosis is mainly caspase-mediated. These compounds also induced a marked reduction in the bcl-2:bax ratio, which was accompanied by caspase-9 and caspase-7 activation and cytochrome-c release to the cytosol. Taken together, these data support the notion that the combination of equol and tamoxifen activates the intrinsic apoptotic pathway more efficiently than each compound alone. Consequently, equol may be used therapeutically in combination treatments and clinical studies to enhance tamoxifen's effect by providing additional protection against estrogen-responsive breast cancers.

  5. Inhibition of histone deacetylases 1 and 6 enhances cytarabine-induced apoptosis in pediatric acute myeloid leukemia cells.

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    Xuelian Xu

    Full Text Available BACKGROUND: Pediatric acute myeloid leukemia (AML remains a challenging disease to treat even with intensified cytarabine-based chemotherapy. Histone deacetylases (HDACs have been reported to be promising therapeutic targets for treating AML. However, HDAC family members that are involved in chemotherapy sensitivities remain unknown. In this study, we sought to identify members of the HDAC family that are involved in cytarabine sensitivities, and to select the optimal HDACI that is most efficacious when combined with cytarabine for treating children with AML. METHODOLOGY: Expression profiles of classes I, II, and IV HDACs in 4 pediatric AML cell lines were determined by Western blotting. Inhibition of class I HDACs by different HDACIs was measured post immnunoprecipitation. Individual down-regulation of HDACs in pediatric AML cells was performed with lentiviral shRNA. The effects of cytarabine and HDACIs on apoptosis were determined by flow cytometry analysis. RESULTS: Treatments with structurally diverse HDACIs and HDAC shRNA knockdown experiments revealed that down-regulation of both HDACs 1 and 6 is critical in enhancing cytarabine-induced apoptosis in pediatric AML, at least partly mediated by Bim. However, down-regulation of HDAC2 may negatively impact cytarabine sensitivities in the disease. At clinically achievable concentrations, HDACIs that simultaneously inhibited both HDACs 1 and 6 showed the best anti-leukemic activities and significantly enhanced cytarabine-induced apoptosis. CONCLUSION: Our results further confirm that HDACs are bona fide therapeutic targets for treating pediatric AML and suggest that pan-HDACIs may be more beneficial than isoform-specific drugs.

  6. MiR-26b inhibits melanoma cell proliferation and enhances apoptosis by suppressing TRAF5-mediated MAPK activation

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    Li, Meng; Long, Chaoqin; Yang, Guilan; Luo, Yang; Du, Hua, E-mail: lemonlives_dr@163.com

    2016-03-11

    Alterations in microRNA-26b (miR-26b) expression have been shown to participate in various malignant tumor developments. However, the possible function of miR-26b in human melanoma cells remains unclarified. In this study, quantitative polymerase chain reaction was used to explore the expression profiles of miR-26b in melanoma cells. The effect of miR-26b on cell viability was determined by using MTT assays and colony formation assay. The apoptosis levels were evaluated by using Annexin V/fluorescein isothiocyanate (FITC) apoptosis detection kit and the apoptosis cells were confirmed by Transmission Electron Microscopy (TEM). Luciferase reporter plasmids were constructed to confirm direct targeting. Our study found that the expression of miR-26b was downregulated in human melanoma specimens. Overexpression of miR-26b significantly increased the anti-proliferative effects and apoptosis in A375 and B16F10 melanoma cells. In addition, luciferase gene reporter assays confirmed that TRAF5 was a direct target gene of miR-26b and the anti-tumor effect of miR-26b in melanoma cells was significantly counteracted by treatment with TRAF5 overexpression. Furthermore, the molecular mechanisms underlying the tumor suppressor of miR-26b in malignant melanomas may be due to the dephosphorylation of MAPK pathway caused by the decrease in TRAF5 expression when miR-26b is up-regulated in melanoma cells. These findings indicate that miR-26b might influence TRAF5-MAPK signaling pathways to facilitate the malignant progression of melanoma cells. - Highlights: • miR-26b is downregulated in human melanomas. • miR-26b suppressed melanoma cell proliferation and enhanced cell apoptosis. • TRAF5 is a direct target of miR-26b and inversely correlates with miR-26b expression. • miR-26b modulated MAPK signaling pathway by targeting TRAF5.

  7. Inhibition of autophagy enhances DNA damage-induced apoptosis by disrupting CHK1-dependent S phase arrest

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    Liou, Jong-Shian; Wu, Yi-Chen; Yen, Wen-Yen; Tang, Yu-Shuan [Institute of Cellular and Organismic Biology, Academia Sinica, Taipei 115, Taiwan, ROC (China); Kakadiya, Rajesh B.; Su, Tsann-Long [Institute of Biomedical Sciences, Academia Sinica, Taipei 115, Taiwan, ROC (China); Yih, Ling-Huei, E-mail: lhyih@gate.sinica.edu.tw [Institute of Cellular and Organismic Biology, Academia Sinica, Taipei 115, Taiwan, ROC (China)

    2014-08-01

    DNA damage has been shown to induce autophagy, but the role of autophagy in the DNA damage response and cell fate is not fully understood. BO-1012, a bifunctional alkylating derivative of 3a-aza-cyclopenta[a]indene, is a potent DNA interstrand cross-linking agent with anticancer activity. In this study, BO-1012 was found to reduce DNA synthesis, inhibit S phase progression, and induce phosphorylation of histone H2AX on serine 139 (γH2AX) exclusively in S phase cells. Both CHK1 and CHK2 were phosphorylated in response to BO-1012 treatment, but only depletion of CHK1, but not CHK2, impaired BO-1012-induced S phase arrest and facilitated the entry of γH2AX-positive cells into G2 phase. CHK1 depletion also significantly enhanced BO-1012-induced cell death and apoptosis. These results indicate that BO-1012-induced S phase arrest is a CHK1-dependent pro-survival response. BO-1012 also resulted in marked induction of acidic vesicular organelle (AVO) formation and microtubule-associated protein 1 light chain 3 (LC3) processing and redistribution, features characteristic of autophagy. Depletion of ATG7 or co-treatment of cells with BO-1012 and either 3-methyladenine or bafilomycin A1, two inhibitors of autophagy, not only reduced CHK1 phosphorylation and disrupted S phase arrest, but also increased cleavage of caspase-9 and PARP, and cell death. These results suggest that cells initiate S phase arrest and autophagy as pro-survival responses to BO-1012-induced DNA damage, and that suppression of autophagy enhances BO-1012-induced apoptosis via disruption of CHK1-dependent S phase arrest. - Highlights: • Autophagy inhibitors enhanced the cytotoxicity of a DNA alkylating agent, BO-1012. • BO-1012-induced S phase arrest was a CHK1-dependent pro-survival response. • Autophagy inhibition enhanced BO-1012 cytotoxicity via disrupting the S phase arrest.

  8. Treadmill exercise enhances spatial learning ability through suppressing hippocampal apoptosis in Huntington's disease rats.

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    Ji, Eun-Sang; Kim, You-Mi; Shin, Mal-Soon; Kim, Chang-Ju; Lee, Kwang-Sik; Kim, Kijeong; Ha, Jonglin; Chung, Yong-Rak

    2015-06-01

    Huntington's disease is a chronic neurodegenerative disorder inherited in an autosomal dominant fashion, and characterized as involuntary movement. Quinolinic acid has been used to produce an animal model of Huntington's disease. In the present study, the effect of treadmill exercise on spatial-learning ability and motor coordination focusing on the apoptosis in the hippocampus was investigated using quinolinic acid-induced Huntington's disease rats. Huntington's disease was induced by unilateral intrastriatal injection of quinolinic acid (2 μL of 100 nmol) using stereotaxic instrument. The rats in the treadmill exercise groups were subjected to run on a treadmill for 30 min once a day during 14 days. Spatial learning ability and motor coordination were determined by radial 8-arm maze test and rota-rod test. Immunohistochemistry for caspase-3 and western blot for Bax and Bcl-2 were also conducted for the detection of apoptosis. In the present results, spatial learning ability and motor coordination were deteriorated by intrastriatal injection of quinolinic acid. In contrast, treadmill exercise exerted ameliorating effect on quinolinic acid-induced deterioration of spatial learning ability and motor coordination. Bcl-2 expression in the hippocampus was de-creased and expressions of casepase-3 and Bax in the hippocampus were increased in the quinolinic acid-induced Huntington's disease rats. Treadmill exercise increased Bcl-2 expression and decreased expressions of casepase-3 and Bax in the Huntington's disease rats. The present results showed that treadmill exercise might ameliorate quinolinic acid-induced loss of spatial learning ability and motor coordination by suppressing apoptosis in the hippocampus.

  9. Chloroquine and hydroxychloroquine inhibit bladder cancer cell growth by targeting basal autophagy and enhancing apoptosis

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    Yi-Chia Lin

    2017-05-01

    Full Text Available Chloroquine (CQ and hydroxychloroquine (HCQ, two antimalarial drugs, are suggested to have potential anticancer properties. in the present study, we investigated the effects of CQ and HCQ on cell growth of bladder cancer with emphasis on autophagy inhibition and apoptosis induction in vitro. The results showed that CQ and HCQ inhibited the proliferation of multiple human bladder cell lines (including RT4, 5637, and T24 in a time- and dose-dependent fashion, especially in advanced bladder cancer cell lines (5637 and T24 compared to immortalized uroepithelial cells (SV-Huc-1 or other reference cancer cell lines (PC3 and MCF-7. We found that 24-hour treatment of CQ or HCQ significantly decreased the clonogenic formation in 5637 and T24 cells compared to SV-Huc-1. As human bladder cancer tumor exhibits high basal level of autophagic activities, we detected the autophagic flux in cells treated with CQ and HCQ, showing an alternation in LC3 flux in CQ- or HCQ-treated cells. Moreover, bladder cancer cells treated with CQ and HCQ underwent apoptosis, resulting in increased caspase 3/7 activities, increased level of cleaved poly(ADP-ribose polymerase (PARP, caspase 3, and DNA fragmentation. Given these results, targeting autophagy with CQ and HCQ represents an effective cancer therapeutic strategy against human bladder cancer.

  10. Chloroquine and hydroxychloroquine inhibit bladder cancer cell growth by targeting basal autophagy and enhancing apoptosis.

    Science.gov (United States)

    Lin, Yi-Chia; Lin, Ji-Fan; Wen, Sheng-I; Yang, Shan-Che; Tsai, Te-Fu; Chen, Hung-En; Chou, Kuang-Yu; Hwang, Thomas I-Sheng

    2017-05-01

    Chloroquine (CQ) and hydroxychloroquine (HCQ), two antimalarial drugs, are suggested to have potential anticancer properties. in the present study, we investigated the effects of CQ and HCQ on cell growth of bladder cancer with emphasis on autophagy inhibition and apoptosis induction in vitro. The results showed that CQ and HCQ inhibited the proliferation of multiple human bladder cell lines (including RT4, 5637, and T24) in a time- and dose-dependent fashion, especially in advanced bladder cancer cell lines (5637 and T24) compared to immortalized uroepithelial cells (SV-Huc-1) or other reference cancer cell lines (PC3 and MCF-7). We found that 24-hour treatment of CQ or HCQ significantly decreased the clonogenic formation in 5637 and T24 cells compared to SV-Huc-1. As human bladder cancer tumor exhibits high basal level of autophagic activities, we detected the autophagic flux in cells treated with CQ and HCQ, showing an alternation in LC3 flux in CQ- or HCQ-treated cells. Moreover, bladder cancer cells treated with CQ and HCQ underwent apoptosis, resulting in increased caspase 3/7 activities, increased level of cleaved poly(ADP-ribose) polymerase (PARP), caspase 3, and DNA fragmentation. Given these results, targeting autophagy with CQ and HCQ represents an effective cancer therapeutic strategy against human bladder cancer. Copyright © 2017. Published by Elsevier Taiwan.

  11. Enhancement of hyperthermia-induced apoptosis by 5Z-7-oxozeaenol, a TAK1 inhibitor, in A549 cells.

    Science.gov (United States)

    Li, Peng; Zhao, Qing-Li; Jawaid, Paras; Rehman, Mati Ur; Sakurai, Hiroaki; Kondo, Takashi

    2016-09-01

    KRAS mutant lung cancers have long been considered as untreatable with drugs. Transforming growth factor-β-activated kinase 1 (TAK1) appears to play an anti-apoptotic role in response to multiple stresses and has been reported to be a responsive kinase that regulates cell survival in KRAS-dependent cells. In this study, in order to find a useful approach to treat KRAS mutant lung cancer, we focused on the combined effects of 5Z-7-oxozeaenol, a TAK1 inhibitor, with hyperthermia (HT) in KRAS mutant lung cancer cell line A549. Annexin V-FITC/PI assay, cell cycle analysis, and colony formation assay revealed a significant enhancement in apoptosis induced by HT treatment, when the cells were pre-incubated with 5Z-7-oxozeaenol in a dose-dependent manner. The enhanced apoptosis by 5Z-7-oxozeaenol was accompanied by a significant increase in reactive oxygen species (ROS) generation and loss of mitochondrial membrane potential (MMP). In addition, western blot showed that 5Z-7-oxozeaenol enhanced HT-induced expressions of cleaved caspase-3, cleaved caspase-8, and HSP70 and decreased HT-induced expressions of Bcl-2, p-p38, p-JNK, and LC3. Moreover, 5Z-7-oxozeaenol pre-treatment resulted in a marked elevation of intracellular calcium level which might be associated with endoplasmic reticulum (ER) stress-related pathway. Taken together, our data provides further insights of the mechanism of action of 5Z-7-oxozeaenol and HT treatment, and their potential application as a novel approache to treat patients with KRAS mutant lung cancer.

  12. Chemosensitizing effects of carbon-based nanomaterials in cancer cells: enhanced apoptosis and inhibition of proliferation as underlying mechanisms.

    Science.gov (United States)

    Erdmann, Kati; Ringel, Jessica; Hampel, Silke; Rieger, Christiane; Huebner, Doreen; Wirth, Manfred P; Fuessel, Susanne

    2014-10-10

    Recent studies have shown that carbon nanomaterials such as carbon nanofibres (CNFs) and multi-walled carbon nanotubes (CNTs) can exert antitumor activities themselves and sensitize cancer cells to conventional chemotherapeutics such as carboplatin and cisplatin. In the present study, the chemosensitizing effect of CNFs and CNTs on cancer cells of urological origin was investigated regarding the underlying mechanisms. Prostate cancer (DU-145, PC-3) and bladder cancer (EJ28) cells were treated with carbon nanomaterials (CNFs, CNTs) and chemotherapeutics (carboplatin, cisplatin) alone as well as in combination for 24 h. Forty-eight(EJ28) or 72 h (DU-145, PC-3) after the end of treatment the effects on cellular proliferation,clonogenic survival, cell death rate and cell cycle distribution were evaluated. Depending on the cell line, simultaneous administration of chemotherapeutics and carbon nanomaterials produced an additional inhibition of cellular proliferation and clonogenic survival of up to 77% and 98%, respectively, compared to the inhibitory effects of the chemotherapeutics alone. These strongly enhanced antiproliferative effects were accompanied by an elevated cell death rate, which was predominantly mediated via apoptosis and not by necrosis. The antitumor effects of combinations with CNTs were less pronounced than those with CNFs. The enhanced effects of the combinatory treatments on cellular function were mostly of additive to partly synergistic nature. Furthermore, cell cycle analysis demonstrated an arrest at the G2/M phase mediated by a monotreatment with chemotherapeutics. Following combinatory treatments, mostly less than or nearly additive increases of cell fractions in the G2/M phase could be observed. In conclusion,the pronounced chemosensitizing effects of CNFs and CNTs were mediated by an enhanced apoptosis and inhibition of proliferation. The combination of carbon-based nanomaterials and conventional chemotherapeutics represents a novel approach

  13. Nuclear factor-kappa B inhibition can enhance apoptosis of differentiated thyroid cancer cells induced by 131I.

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    Zhaowei Meng

    Full Text Available OBJECTIVE: To evaluate changes of nuclear factor-kappa B (NF-κB during radioiodine 131 ((131I therapy and whether NF-κB inhibition could enhance (131I-induced apoptosis in differentiated thyroid cancer (DTC cells in a synergistic manner. METHODS: Three human DTC cell lines were used. NF-κB inhibition was achieved by using a NF-κB inhibitor (Bay 11-7082 or by p65 siRNA transfection. Methyl-thiazolyl-tetrazolium assay was performed for cell viability assessment. DNA-binding assay, luciferase reporter assay, and Western blot were adopted to determine function and expression changes of NF-κB. Then NF-κB regulated anti-apoptotic factors XIAP, cIAP1, and Bcl-xL were measured. Apoptosis was analyzed by Western blot for caspase 3 and PARP, and by flow cytometry as well. An iodide uptake assay was performed to determine whether NF-κB inhibition could influence radioactive iodide uptake. RESULTS: The methyl-thiazolyl-tetrazolium assay showed significant decrease of viable cells by combination therapy than by mono-therapies. The DNA-binding assay and luciferase reporter assay showed enhanced NF-κB function and reporter gene activities due to (131I, yet significant suppression was achieved by NF-κB inhibition. Western blot proved (131I could increase nuclear NF-κB concentration, while NF-κB inhibition reduced NF-κB concentration. Western blot also demonstrated significant up-regulation of XIAP, cIAP1, and Bcl-xL after (131I therapy. And inhibition of NF-κB could significantly down-regulate these factors. Finally, synergism induced by combined therapy was displayed by significant enhancements of cleaved caspase 3 and PARP from Western blot, and of Annexin V positively staining from flow cytometry. The iodine uptake assay did not show significant changes when NF-κB was inhibited. CONCLUSION: We demonstrated that (131I could induce NF-κB activation, which would attenuate (131I efficacy in DTC cells. NF-κB inhibition by Bay 11-7082 or by p65 si

  14. Ecdysone-Induced Receptor Tyrosine Phosphatase PTP52F Regulates Drosophila Midgut Histolysis by Enhancement of Autophagy and Apoptosis

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    Santhanam, Abirami; Peng, Wen-Hsin; Yu, Ya-Ting; Sang, Tzu-Kang

    2014-01-01

    The rapid removal of larval midgut is a critical developmental process directed by molting hormone ecdysone during Drosophila metamorphosis. To date, it remains unclear how the stepwise events can link the onset of ecdysone signaling to the destruction of larval midgut. This study investigated whether ecdysone-induced expression of receptor protein tyrosine phosphatase PTP52F regulates this process. The mutation of the Ptp52F gene caused significant delay in larval midgut degradation. Transitional endoplasmic reticulum ATPase (TER94), a regulator of ubiquitin proteasome system, was identified as a substrate and downstream effector of PTP52F in the ecdysone signaling. The inducible expression of PTP52F at the puparium formation stage resulted in dephosphorylation of TER94 on its Y800 residue, ensuring the rapid degradation of ubiquitylated proteins. One of the proteins targeted by dephosphorylated TER94 was found to be Drosophila inhibitor of apoptosis 1 (DIAP1), which was rapidly proteolyzed in cells with significant expression of PTP52F. Importantly, the reduced level of DIAP1 in response to inducible PTP52F was essential not only for the onset of apoptosis but also for the initiation of autophagy. This study demonstrates a novel function of PTP52F in regulating ecdysone-directed metamorphosis via enhancement of autophagic and apoptotic cell death in doomed Drosophila midguts. PMID:24550005

  15. Choline deficiency induced by Mycoplasma fermentans enhances apoptosis of rat astrocytes.

    Science.gov (United States)

    Ben-Menachem, G; Mousa, A; Brenner, T; Pinto, F; Zähringer, U; Rottem, S

    2001-07-24

    A choline uptake system accumulating free choline in an energy-dependent process is described in Mycoplasma fermentans. The uptake system has a K(m) of 2.2x10(-5) M and a V(max) of 0.15 nmol 10 min(-1) mg(-1) cell protein and the choline incorporated could be recovered in the soluble fraction as free choline, phosphorylcholine and CDP-choline. Choline accumulation by M. fermentans resulted in a marked choline depletion of the growth medium. The choline depletion of an astrocyte cell culture induced by M. fermentans was associated with the apoptotic death of the cells. Apoptosis was not obtained with heat-inactivated mycoplasmas and could be reversed by the addition of free choline to the growth medium.

  16. Combined exercise ameliorates ovariectomy-induced cognitive impairment by enhancing cell proliferation and suppressing apoptosis.

    Science.gov (United States)

    Kim, Tae-Woon; Kim, Chang-Sun; Kim, Ji-Yeon; Kim, Chang-Ju; Seo, Jin-Hee

    2016-01-01

    Estrogen plays an important role in cognitive function, including attention, learning, and memory, and affects the structure and function of brain areas. We investigated the effects of combined exercise on memory deficits induced by ovariectomy (OVX) in relation to cell proliferation and apoptosis in the hippocampus. Rats were randomly divided into four groups: sham, sham and exercise, OVX, and OVX and exercise. Rats in combined exercise groups were subjected to 3 days of resistance training and 3 days of running (for a total of 6 d/wk) for eight consecutive weeks. Rats were tested in step-down avoidance task and Morris water maze task to verify the effects of OVX on short-term and spatial working memory. In the present study, the number of BrdU-positive and doublecortin-positive cells and expression of brain-derived neurotrophic factor, TrkB, and Bcl-2 decreased; expression of Bax and the number of caspase-3-positive and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling-positive cells increased; and short-term and spatial working memory decreased in the OVX group compared with the sham group. Conversely, when the combined exercise group was compared with the OVX group, the number of BrdU-positive and doublecortin-positive cells and expression of brain-derived neurotrophic factor, TrkB, and Bcl-2 increased; expression of Bax and the number of caspase-3-positive and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling-positive cells decreased; and short-term and spatial working memory increased. Combined exercise increases cell proliferation and inhibits apoptosis in the hippocampus and improves cognitive function despite estrogen deficiency.

  17. p38 Activation Is Required Upstream of Potassium Current Enhancement and Caspase Cleavage in Thiol Oxidant-Induced Neuronal Apoptosis

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    McLaughlin, BethAnn; Pal, Sumon; Tran, Minhnga P.; Parsons, Andrew A.; Barone, Frank C.; Erhardt, Joseph A.; Aizenman, Elias

    2013-01-01

    Oxidant-induced neuronal apoptosis has been shown to involve potassium and zinc dysregulation, energetic dysfunction, activation of stress-related kinases, and caspase cleavage. The temporal ordering and interdependence of these events was investigated in primary neuronal cultures exposed to the sulfhydryl oxidizing agent 2,2′-dithiodipyridine (DTDP), a compound that induces the intracellular release of zinc. We previously observed that tetraethylammonium (TEA), high extracellular potassium, or cysteine protease inhibitors block apoptosis induced by DTDP. We now report that both p38 and extracellular signal-regulated kinase phosphorylation are evident in neuronal cultures within 2 hr of a brief exposure to 100 μm DTDP. However, only p38 inhibition is capable of blocking oxidant-induced toxicity. Cyclohexamide or actinomycin D does not attenuate DTDP-induced cell death, suggesting that posttranslational modification of existing targets, rather than transcriptional activation, is responsible for the deleterious effects of p38. Indeed, an early robust increase in TEA-sensitive potassium channel currents induced by DTDP is attenuated by p38 inhibition but not by caspase inhibition. Moreover, we found that activation of p38 is required for caspase 3 and 9 cleavage, suggesting that potassium currents enhancement is required for caspase activation. Finally, we observed that DTDP toxicity could be blocked with niacinamide or benzamide, inhibitors of poly (ADP-ribose) synthetase. Based on these findings, we conclude that oxidation of sulfhydryl groups on intracellular targets results in intracellular zinc release, p38 phosphorylation, enhancement of potassium currents, caspase cleavage, energetic dysfunction, and translationally independent apoptotic cell death. PMID:11331359

  18. Small interfering RNA targeting mcl-1 enhances proteasome inhibitor-induced apoptosis in various solid malignant tumors

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    Zhou Wei

    2011-11-01

    Full Text Available Abstract Background Targeting the ubiquitin-proteasome pathway is a promising approach for anticancer strategies. Recently, we found Bik accumulation in cancer cell lines after they were treated with bortezomib. However, recent evidence indicates that proteasome inhibitors may also induce the accumulation of anti-apoptotic Bcl-2 family members. The current study was designed to analyze the levels of several anti-apoptotic members of Bcl-2 family in different human cancer cell lines after they were treated with proteasome inhibitors. Methods Different human cancer cell lines were treated with proteasome inhibitors. Western blot were used to investigate the expression of Mcl-1 and activation of mitochondrial apoptotic signaling. Cell viability was investigated using SRB assay, and induction of apoptosis was measured using flow cytometry. Results We found elevated Mcl-1 level in human colon cancer cell lines DLD1, LOVO, SW620, and HCT116; human ovarian cancer cell line SKOV3; and human lung cancer cell line H1299, but not in human breast cancer cell line MCF7 after they were treated with bortezomib. This dramatic Mcl-1 accumulation was also observed when cells were treated with other two proteasome inhibitors, MG132 and calpain inhibitor I (ALLN. Moreover, our results showed Mcl-1 accumulation was caused by stabilization of the protein against degradation. Reducing Mcl-1 accumulation by Mcl-1 siRNA reduced Mcl-1 accumulation and enhanced proteasome inhibitor-induced cell death and apoptosis, as evidenced by the increased cleavage of caspase-9, caspase-3, and poly (ADP-ribose polymerase. Conclusions Our results showed that it was not only Bik but also Mcl-1 accumulation during the treatment of proteasome inhibitors, and combining proteasome inhibitors with Mcl-1 siRNA would enhance the ultimate anticancer effect suggesting this combination might be a more effective strategy for cancer therapy.

  19. Mitochondrial division inhibitor 1 (mdivi-1) enhances death receptor-mediated apoptosis in human ovarian cancer cells

    Science.gov (United States)

    Wang, Jingnan; Hansen, Karyn; Edwards, Robert; Van Houten, Bennett; Qian, Wei

    2014-01-01

    Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) based strategy is a promising targeted therapeutic approach for the treatment of a variety of cancers including ovarian cancer. However, the inherent or acquired resistance of tumor cells to TRAIL limits the potential application of TRAIL-mediated therapy. In this study, we identified that mitochondrial division inhibitor-1 (mdivi-1) is able to enhance the sensitivity of human ovarian cancer cells to death receptor ligands including TRAIL, FAS ligands, and TNF-α. Importantly, the combination of TRAIL and mdivi-1 has no apparent cytotoxic effect on non-transformed human cells, indicating a significant therapeutic window. We identified that caspase-8 and not the modulation of TRAIL receptors is required for the combination effect of TRAIL and mdivi-1. We further demonstrated that the enhanced efficacy of combination of mdivi-1 and death ligands is not dependent on the originally reported target of mdivi-1, Drp1, and is also not dependent on the two important pro-apoptotic Bcl-2 family proteins Bax and Bak. Thus, our study presents a novel strategy in enhancing the apoptotic effect of death receptor ligands and provides a new effective TRAIL-based combination approach for treating human ovarian cancer. PMID:25446129

  20. RGD-avidin–biotin pretargeting to αvβ₃ integrin enhances the proapoptotic activity of TNFα related apoptosis inducing ligand (TRAIL)

    NARCIS (Netherlands)

    Tarrus, M.; Sloot, A.M. van der; Temming, K.; Lacombe, M.; Opdam, F.; Quax, W.J.; Molema, G.; Poelstra, K.; Kok, R.J.

    2008-01-01

    Recombinant TNF-related apoptosis-inducing ligand (TRAIL) is considered a powerful and selective inducer of tumor cell death. We hypothesize that TRAIL’s potential as anticancer agent can be enhanced further by promoting its accumulation in tumor tissue. For this purpose, we developed TRAIL

  1. RGD-avidin-biotin pretargeting to alpha(v)beta(3) integrin enhances the proapoptotic activity of TNF alpha related apoptosis inducing ligand (TRAIL)

    NARCIS (Netherlands)

    Tarrus, Marc; van der Sloot, Almer M.; Temming, Kai; Lacombe, Marie; Opdam, Frank; Quax, Wim J.; Molema, Grietje; Poelstra, Klaas; Kok, Robbert J.

    Recombinant TNF-related apoptosis-inducing ligand (TRAIL) is considered a powerful and selective inducer of tumor cell death. We hypothesize that TRAIL's potential as anticancer agent can be enhanced further by promoting its accumulation in tumor tissue. For this purpose, we developed TRAIL

  2. Nesfatin-1 inhibits proliferation and enhances apoptosis of human adrenocortical H295R cells.

    Science.gov (United States)

    Ramanjaneya, Manjunath; Tan, Bee K; Rucinski, Marcin; Kawan, Mohamed; Hu, Jiamiao; Kaur, Jaspreet; Patel, Vanlata H; Malendowicz, Ludwik K; Komarowska, Hanna; Lehnert, Hendrik; Randeva, Harpal S

    2015-07-01

    NUCB2/nesfatin and its proteolytically cleaved product nesfatin-1 are recently discovered anorexigenic hypothalamic neuroproteins involved in energy homeostasis. It is expressed both centrally and in peripheral tissues, and appears to have potent metabolic actions. NUCB2/nesfatin neurons are activated in response to stress. Central nesfatin-1 administration elevates circulating ACTH and corticosterone levels. Bilateral adrenalectomy increased NUCB2/nesfatin mRNA levels in rat paraventricular nuclei. To date, studies have not assessed the effects of nesfatin-1 stimulation on human adrenocortical cells. Therefore, we investigated the expression and effects of nesfatin-1 in a human adrenocortical cell model (H295R). Our findings demonstrate that NUCB2 and nesfatin-1 are expressed in human adrenal gland and human adrenocortical cells (H295R). Stimulation with nesfatin-1 inhibits the growth of H295R cells and promotes apoptosis, potentially via the involvement of Bax, BCL-XL and BCL-2 genes as well as ERK1/2, p38 and JNK1/2 signalling cascades. This has implications for understanding the role of NUCB2/nesfatin in adrenal zonal development. NUCB2/nesfatin may also be a therapeutic target for adrenal cancer. However, further studies using in vivo models are needed to clarify these concepts. © 2015 Society for Endocrinology.

  3. A novel firefly luciferase biosensor enhances the detection of apoptosis induced by ESAT-6 family proteins of Mycobacterium tuberculosis

    Energy Technology Data Exchange (ETDEWEB)

    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.

  4. RGD-avidin-biotin pretargeting to alpha v beta 3 integrin enhances the proapoptotic activity of TNF alpha related apoptosis inducing ligand (TRAIL).

    Science.gov (United States)

    Tarrus, Marc; van der Sloot, Almer M; Temming, Kai; Lacombe, Marie; Opdam, Frank; Quax, Wim J; Molema, Grietje; Poelstra, Klaas; Kok, Robbert J

    2008-02-01

    Recombinant TNF-related apoptosis-inducing ligand (TRAIL) is considered a powerful and selective inducer of tumor cell death. We hypothesize that TRAIL's potential as anticancer agent can be enhanced further by promoting its accumulation in tumor tissue. For this purpose, we developed TRAIL complexes that bind to angiogenic endothelial cells. We employed an avidin-biotin pretargeting approach, in which biotinylated TRAIL interacted with RGD-equipped avidin. The assembled complexes killed tumor cells (Jurkat T cells) via apoptosis induction. Furthermore, we demonstrated that the association of the RGD-avidin-TRAIL complex onto endothelial cells enhanced the tumor cell killing activity. Endothelial cells were not killed by TRAIL nor its derived complexes. Our approach can facilitate the enrichment of TRAIL onto angiogenic blood vessels, which may enhance intratumoral accumulation. Furthermore, it offers a versatile technology for the complexation of targeting ligands with therapeutic recombinant proteins and by this a novel way to enhance their specificity and activity.

  5. Hericium erinaceus enhances doxorubicin-induced apoptosis in human hepatocellular carcinoma cells.

    Science.gov (United States)

    Lee, Jong Seok; Hong, Eock Kee

    2010-11-28

    It has been demonstrated that the Hericium erinaceus (HE) mushroom, which primarily consists of polysaccharides, possesses anti-tumor activities. However, the mechanisms by which HE inhibits human hepatocellular carcinoma growth remain unknown. Our study demonstrates that HE acts as an enhancer to sensitize doxorubicin (Dox)-mediated apoptotic signaling, and this sensitization can be achieved by reducing c-FLIP expression via JNK activation and enhancing intracellular Dox accumulation via the inhibition of NF-κB activity. These findings suggest that HE in combination with Dox serves as an effective tool for treating drug-resistant human hepatocellular carcinoma. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  6. Tandem therapy for retinoblastoma: immunotherapy and chemotherapy enhance cytotoxicity on retinoblastoma by increasing apoptosis.

    Science.gov (United States)

    Liu, Qiuling; Wang, Yafeng; Wang, Han; Liu, Yingying; Liu, Tao; Kunda, Patricia Elena

    2013-08-01

    The goal of this study was to provide an experimental basis for the clinical application of cell immunotherapy on RB in combination with chemotherapy treatment and to explore the mechanism of their combined cytotoxicity. We investigated the antitumor effect of cytokine-induced killer cells (CIK), co-cultivated with dendritic cells pulsed with tumor antigens (DC-Ag) and/or with carboplatin. Cytotoxicity was evaluated on a retinoblastoma cell line (RB-Y79) by FCM and immunofluorescence microscopy. Time-lapse video microscopy was used to follow the sequence of events during the carboplatin and CIK cytotoxicity. Our results showed that a small proportion of RB-Y79 cells died after a low-dose carboplatin application. The cell population recovered 5 days after carboplatin was removed from the culture medium. Three times fewer normal epithelium retina cell lines (hTERT-RPE1) died at the same carboplatin dose. CIK achieved 5 times more cytotoxicity against RB cells pre-treated with low dose of carboplatin, showing the highest antitumor activity in the tandem carboplatin-DC-Ag-CIK-carboplatin treatment. Time-lapse video microscopy revealed that carboplatin-preconditioned RB cells are more avidly engaged by CIK cells, increasing RB mortality and resulting in an overall increment in apoptosis. This study provides evidence that carboplatin combined with cell immunotherapy is superior to carboplatin alone to kill RB cells in vitro. We propose that a primary application of a low dose of a chemotherapeutic drug that is able to attack the tumor, and a subsequent treatment with highly effective immunotherapy based on DC-Ag-CIK cells could be a safe and selective treatment for RB.

  7. Mice lacking thyroid hormone receptor Beta show enhanced apoptosis and delayed liver commitment for proliferation after partial hepatectomy.

    Directory of Open Access Journals (Sweden)

    Raquel López-Fontal

    Full Text Available BACKGROUND: The role of thyroid hormones and their receptors (TR during liver regeneration after partial hepatectomy (PH was studied using genetic and pharmacologic approaches. Roles in liver regeneration have been suggested for T3, but there is no clear evidence distinguishing the contribution of increased amounts of T3 from the modulation by unoccupied TRs. METHODOLOGY/PRINCIPAL FINDINGS: Mice lacking TRalpha1/TRbeta or TRbeta alone fully regenerated liver mass after PH, but showed delayed commitment to the initial round of hepatocyte proliferation and transient but intense apoptosis at 48h post-PH, affecting approximately 30% of the remaining hepatocytes. Pharmacologically induced hypothyroidism yielded similar results. Loss of TR activity was associated with enhanced nitrosative stress in the liver remnant, due to an increase in the activity of the nitric oxide synthase (NOS 2 and 3, caused by a transient decrease in the concentration of asymmetric dimethylarginine (ADMA, a potent NOS inhibitor. This decrease in the ADMA levels was due to the presence of a higher activity of dimethylarginineaminohydrolase-1 (DDAH-1 in the regenerating liver of animals lacking TRalpha1/TRbeta or TRbeta. DDAH-1 expression and activity was paralleled by the activity of FXR, a transcription factor involved in liver regeneration and up-regulated in the absence of TR. CONCLUSIONS/SIGNIFICANCE: We report that TRs are not required for liver regeneration; however, hypothyroid mice and TRbeta- or TRalpha1/TRbeta-deficient mice exhibit a delay in the restoration of liver mass, suggesting a specific role for TRbeta in liver regeneration. Altered regenerative responses are related with a delay in the expression of cyclins D1 and E, and the occurrence of liver apoptosis in the absence of activated TRbeta that can be prevented by administration of NOS inhibitors. Taken together, these results indicate that TRbeta contributes significantly to the rapid initial round of

  8. Inhibition of apoptosis signal-regulating kinase 1 alters the wound epidermis and enhances auricular cartilage regeneration.

    Directory of Open Access Journals (Sweden)

    Qian-Shi Zhang

    Full Text Available Why regeneration does not occur in mammals remains elusive. In lower vertebrates, epimorphic regeneration of the limb is directed by the wound epidermis, which controls blastema formation to promote regrowth of the appendage. Herein, we report that knockout (KO or inhibition of Apoptosis Signal-regulated Kinase-1 (ASK1, also known as mitogen-activated protein kinase kinase kinase 5 (MAP3K5, after full thickness ear punch in mice prolongs keratinocyte activation within the wound epidermis and promotes regeneration of auricular cartilage. Histological analysis showed the ASK1 KO ears displayed enhanced protein markers associated with blastema formation, hole closure and regeneration of auricular cartilage. At seven days after punch, the wound epidermis morphology was markedly different in the KO, showing a thickened stratum corneum with rounded cell morphology and a reduction of both the granular cell layer and decreased expression of filament aggregating protein. In addition, cytokeratin 6 was expressed in the stratum spinosum and granulosum. Topical application of inhibitors of ASK1 (NQDI-1, the upstream ASK1 activator, calcium activated mitogen kinase 2 (KN93, or the downstream target, c-Jun N-terminal kinase (SP600125 also resulted in enhanced regeneration; whereas inhibition of the other downstream target, the p38 α/β isoforms, (SB203580 had no effect. The results of this investigation indicate ASK1 inhibition prolongs keratinocyte and blastemal cell activation leading to ear regeneration.

  9. Inhibition of apoptosis signal-regulating kinase 1 alters the wound epidermis and enhances auricular cartilage regeneration.

    Science.gov (United States)

    Zhang, Qian-Shi; Kurpad, Deepa S; Mahoney, My G; Steinbeck, Marla J; Freeman, Theresa A

    2017-01-01

    Why regeneration does not occur in mammals remains elusive. In lower vertebrates, epimorphic regeneration of the limb is directed by the wound epidermis, which controls blastema formation to promote regrowth of the appendage. Herein, we report that knockout (KO) or inhibition of Apoptosis Signal-regulated Kinase-1 (ASK1), also known as mitogen-activated protein kinase kinase kinase 5 (MAP3K5), after full thickness ear punch in mice prolongs keratinocyte activation within the wound epidermis and promotes regeneration of auricular cartilage. Histological analysis showed the ASK1 KO ears displayed enhanced protein markers associated with blastema formation, hole closure and regeneration of auricular cartilage. At seven days after punch, the wound epidermis morphology was markedly different in the KO, showing a thickened stratum corneum with rounded cell morphology and a reduction of both the granular cell layer and decreased expression of filament aggregating protein. In addition, cytokeratin 6 was expressed in the stratum spinosum and granulosum. Topical application of inhibitors of ASK1 (NQDI-1), the upstream ASK1 activator, calcium activated mitogen kinase 2 (KN93), or the downstream target, c-Jun N-terminal kinase (SP600125) also resulted in enhanced regeneration; whereas inhibition of the other downstream target, the p38 α/β isoforms, (SB203580) had no effect. The results of this investigation indicate ASK1 inhibition prolongs keratinocyte and blastemal cell activation leading to ear regeneration.

  10. Transforming growth factor-β-stimulated clone-22 (TSC-22) is an androgen regulated gene that enhances apoptosis in prostate cancer following IGF-IR inhibition

    Science.gov (United States)

    Sprenger, Cynthia C. T.; Haugk, Kathleen; Sun, Shihua; Coleman, Ilsa; Nelson, Peter S.; Vessella, Robert L.; Ludwig, Dale L.; Wu, Jennifer D.; Plymate, Stephen R.

    2009-01-01

    Purpose Inhibition of IGF signaling using the human IGF-IR monoclonal antibody A12 is most effective at inducing apoptosis in prostate cancer xenografts in the presence of androgen. We undertook this study to determine mechanisms for increased apoptosis by A12 in the presence of androgens. Experimental Methods The castrate-resistant human xenograft LuCaP 35V was implanted into intact or castrate SCID mice and treated with A12 weekly. After six weeks of tumor growth animals were sacrificed and tumors removed and analyzed for cell cycle distribution/apoptosis and cDNA arrays were performed. Results In castrate mice the tumors were delayed in G2 with no apoptosis; in contrast tumors from intact mice underwent apoptosis with either a G1 or G2 delay. TSC-22 was significantly elevated in tumors from the intact mice compared to castrate mice, especially in those tumors with the highest levels of apoptosis. In order to further determine the function of TSC-22, we transfected various human prostate cancer cell lines with a plasmid expressing TSC-22. Cell lines overexpressing TSC-22 demonstrated an increase in apoptosis and a delay in G1. When these cell lines were placed subcutaneously in SCID mice a decreased number of animals formed tumors and the rate of tumor growth was decreased compared to control tumors. Conclusions These data indicate that IGF-IR inhibition in the presence of androgen has an enhanced effect on decreasing tumor growth, in part, through increased expression of the tumor suppressor gene TSC-22. PMID:19996218

  11. The scavenger protein apoptosis inhibitor of macrophages (AIM potentiates the antimicrobial response against Mycobacterium tuberculosis by enhancing autophagy.

    Directory of Open Access Journals (Sweden)

    Lucía Sanjurjo

    Full Text Available Apoptosis inhibitor of macrophages (AIM, a scavenger protein secreted by tissue macrophages, is transcriptionally regulated by the nuclear receptor Liver X Receptor (LXR and Retinoid X Receptor (RXR heterodimer. Given that LXR exerts a protective immune response against M. tuberculosis, here we analyzed whether AIM is involved in this response. In an experimental murine model of tuberculosis, AIM serum levels peaked dramatically early after infection with M. tuberculosis, providing an in vivo biological link to the disease. We therefore studied the participation of AIM in macrophage response to M. tuberculosis in vitro. For this purpose, we used the H37Rv strain to infect THP-1 macrophages transfected to stably express AIM, thereby increasing infected macrophage survival. Furthermore, the expression of this protein enlarged foam cell formation by enhancing intracellular lipid content. Phagocytosis assays with FITC-labeled M. tuberculosis bacilli indicated that this protein was not involved in bacterial uptake; however, AIM expression decreased the number of intracellular cfus by up to 70% in bacterial killing assays, suggesting that AIM enhances macrophage mycobactericidal activity. Accordingly, M. tuberculosis-infected AIM-expressing cells upregulated the production of reactive oxygen species. Moreover, real-time PCR analysis showed increased mRNA levels of the antimicrobial peptides cathelicidin and defensin 4B. These increases were concomitant with greater cellular concentrations of the autophagy-related molecules Beclin 1 and LC3II, as well as enhanced acidification of mycobacterial phagosomes and LC3 co-localization. In summary, our data support the notion that AIM contributes to key macrophage responses to M. tuberculosis.

  12. CSE1L/CAS, the cellular apoptosis susceptibility protein, enhances invasion and metastasis but not proliferation of cancer cells

    Directory of Open Access Journals (Sweden)

    Chen Ying-Chun

    2008-07-01

    Full Text Available Abstract Background The cellular apoptosis susceptibility (CAS protein is regarded as a proliferation-associated protein that associates with tumour proliferation as it associates with microtubule and functions in the mitotic spindle checkpoint. However, there is no any actual experimental study showing CAS (or CSE1 and CSE1L can increase the proliferation of cancer cells. Previous pathological study has reported that CAS was strongly positive stained in all of the metastasis melanoma that be examined. Thus, CAS may regulate the invasion and metastasis of cancers. CAS is highly expressed in cancers; if CAS is associated with cancer proliferation, then increased CAS expression should be able to increase the proliferation of cancer cells. We studied whether increased CAS expression can increase cancer cell proliferation and whether CAS regulates the invasion of cancer cells. Methods We enhanced or reduced CAS expression by transfecting CAS or anti-CAS expression vectors into human MCF-7 breast cancer cells. The proliferations of cells were determined by trypan blue exclusion assay and flow cytometry analysis. Invasion of cancer cells were determined by matrigel-based invasion assay. Results Our studies showed that increased CAS expression was unable to enhance cancer cell proliferation. Immunofluorescence showed CAS was distributed in cytoplasm areas near cell membrane and cell protrusions. CAS was localized in cytoplasmic vesicle and immunogold electronmicroscopy showed CAS was located in vesicle membrane. CAS overexpression enhanced matrix metalloproteinase-2 (MMP-2 secretion and cancer cell invasion. Animal experiments showed CAS reduction inhibited the metastasis of B16-F10 melanoma cells by 56% in C57BL/6 mice. Conclusion Our results indicate that CAS increases the invasion but not the proliferation of cancer cells. Thus, CAS plus ECM-degradation proteinases may be used as the markers for predicting the advance of tumour metastasis.

  13. Acute blood glucose fluctuation enhances rat aorta endothelial cell apoptosis, oxidative stress and pro-inflammatory cytokine expression in vivo

    National Research Council Canada - National Science Library

    Wu, Na; Shen, Haitao; Liu, Henan; Wang, Yanjun; Bai, Yu; Han, Ping

    2016-01-01

    .... In the present study, the influence of acute fluctuant hyperglycemia and persistent hyperglycemia on vascular endothelial cell apoptosis, function, oxidative stress and inflammation was examined in vivo...

  14. E2/ER β Enhances Calcineurin Protein Degradation and PI3K/Akt/MDM2 Signal Transduction to Inhibit ISO-Induced Myocardial Cell Apoptosis

    Directory of Open Access Journals (Sweden)

    Kuan-Ho Lin

    2017-04-01

    Full Text Available Secretion of multifunctional estrogen and its receptor has been widely considered as the reason for markedly higher frequency of heart disease in men than in women. 17β-Estradiol (E2, for instance, has been reported to prevent development of cardiac apoptosis via activation of estrogen receptors (ERs. In addition, protein phosphatase such as protein phosphatase 1 (PP1 and calcineurin (PP2B are also involved in cardiac hypertrophy and cell apoptosis signaling. However, the mechanism by which E2/ERβ suppresses apoptosis is not fully understood, and the role of protein phosphatase in E2/ERβ action also needs further investigation. In this study, we observed that E2/ERβ inhibited isoproterenol (ISO-induced myocardial cell apoptosis, cytochrome c release and downstream apoptotic markers. Moreover, we found that E2/ERβ blocks ISO-induced apoptosis in H9c2 cells through the enhancement of calcineurin protein degradation through PI3K/Akt/MDM2 signaling pathway. Our results suggest that supplementation with estrogen and/or overexpression of estrogen receptor β gene may prove to be effective means to treat stress-induced myocardial damage.

  15. Hepatitis B virus X protein and proinflammatory cytokines synergize to enhance TRAIL-induced apoptosis of renal tubular cells by upregulation of DR4.

    Science.gov (United States)

    Yang, Yitong; Wang, Xuan; Zhang, Yueyue; Yuan, Weijie

    2018-02-09

    Persistent infection with hepatitis B virus (HBV) may lead to HBV-associated glomerulonephritis (HBV-GN). Presence of HBV-DNA and -RNA in renal tubular epithelial cells (RTECs) suggests direct virus-induced injury. Increase in proinflammatory cytokines is also observed under these conditions. Apoptosis by tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) plays a significant role in the pathogenesis of HBV-infections. However, the effects of HBV X protein (HBx) on TRAIL-induced apoptosis of RTECs especially under certain inflammatory conditions remain obscure. Here, we show that HBx synergizes with proinflammatory cytokines to significantly increase TRAIL-induced apoptosis of RTECs. HBx markedly up-regulates death receptor-4 (DR4) expression by enhancing the activation of nuclear factor-kappa B (NF-κB) in the presence of proinflammatory cytokines. Dramatic increase in DR4 expression leads to the sensitization of RTECs to TRAIL-induced apoptosis. Furthermore, in patients with HBV-GN, DR4 expression in the kidneys is significantly elevated and is positively correlated with the HBx and proinflammatory cytokines expression. These findings provide a novel insight into the underlying mechanisms of renal tubule lesions induced by HBx in HBV-GN. Copyright © 2018 Elsevier Ltd. All rights reserved.

  16. Enhanced Apoptosis of Monocytes from Complication-Free Juvenile-Onset Diabetes Mellitus Type 1 May Be Ameliorated by TNF-α Inhibitors

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    Jolanta Myśliwska

    2014-01-01

    Full Text Available Diabetes mellitus type 1 is associated with an enhanced apoptosis of different cells and tissues, accelerating occurrence of diabetic microvascular complications. The aim of our study was to determine spontaneous apoptotic potential of the monocyte subsets in juvenile-onset complication-free diabetes mellitus type 1 and to compare them with the corresponding values of the healthy. Moreover, we wanted to assess effects of TNF-R1 blocking agents and those of general TNF-α blocker (Infliximab on spontaneous apoptosis of monocytes. Sixty randomly selected DM1 patients (14.5 ± 3.2 years and 30 healthy (13.5 ± 2.8 years volunteers were enrolled in the study. Our results indicate that three monocyte subsets are distinguishable in the groups of young diabetic patients and the healthy, similarly to in the blood of adults. DM1 patients were characterized by higher values of apoptotic monocytes than the healthy. The manipulation with drugs inhibiting TNF-R1 expression diminished the pool of CD16+ apoptotic monocytes. Infliximab reduced the apoptotic CD16− cells. In conclusion, diabetes mellitus type 1 is associated with greater apoptosis of three monocyte subsets which may contribute to the development of microvascular complications. TNF-α modifiers appear to ameliorate monocyte apoptosis. They may be useful for controlling excessive monocyte apoptosis in diabetic patients.

  17. Sequential treatment with flavopiridol synergistically enhances pyrrolo-1,5-benzoxazepine-induced apoptosis in human chronic myeloid leukaemia cells including those resistant to imatinib treatment.

    Science.gov (United States)

    Bright, Sandra A; Campiani, Giuseppe; Deininger, Michael W; Lawler, Mark; Williams, D Clive; Zisterer, Daniela M

    2010-07-01

    The Bcr-Abl kinase inhibitor, imatinib mesylate, is the front line treatment for chronic myeloid leukaemia (CML), but the emergence of imatinib resistance has led to the search for alternative drug treatments and the examination of combination therapies to overcome imatinib resistance. The pro-apoptotic PBOX compounds are a recently developed novel series of microtubule targeting agents (MTAs) that depolymerise tubulin. Recent data demonstrating enhanced MTA-induced tumour cell apoptosis upon combination with the cyclin dependent kinase (CDK)-1 inhibitor flavopiridol prompted us to examine whether this compound could similarly enhance the effect of the PBOX compounds. We thus characterised the apoptotic and cell cycle events associated with combination therapy of the PBOX compounds and flavopiridol and results showed a sequence dependent, synergistic enhancement of apoptosis in CML cells including those expressing the imatinib-resistant T315I mutant. Flavopiridol reduced the number of polyploid cells formed in response to PBOX treatment but only to a small extent, suggesting that inhibition of endoreplication was unlikely to play a major role in the mechanism by which flavopiridol synergistically enhanced PBOX-induced apoptosis. The addition of flavopiridol following PBOX-6 treatment did however result in an accelerated exit from the G2/M transition accompanied by an enhanced downregulation and deactivation of the CDK1/cyclin B1 complex and an enhanced degradation of the inhibitor of apoptosis protein (IAP) survivin. In conclusion, results from this study highlight the potential of these novel series of PBOX compounds, alone or in sequential combination with flavopiridol, as an effective therapy against CML. (c) 2010 Elsevier Inc. All rights reserved.

  18. HSP72 protects cells from ER stress-induced apoptosis via enhancement of IRE1alpha-XBP1 signaling through a physical interaction.

    LENUS (Irish Health Repository)

    Gupta, Sanjeev

    2010-01-01

    Endoplasmic reticulum (ER) stress is a feature of secretory cells and of many diseases including cancer, neurodegeneration, and diabetes. Adaptation to ER stress depends on the activation of a signal transduction pathway known as the unfolded protein response (UPR). Enhanced expression of Hsp72 has been shown to reduce tissue injury in response to stress stimuli and improve cell survival in experimental models of stroke, sepsis, renal failure, and myocardial ischemia. Hsp72 inhibits several features of the intrinsic apoptotic pathway. However, the molecular mechanisms by which Hsp72 expression inhibits ER stress-induced apoptosis are not clearly understood. Here we show that Hsp72 enhances cell survival under ER stress conditions. The UPR signals through the sensor IRE1alpha, which controls the splicing of the mRNA encoding the transcription factor XBP1. We show that Hsp72 enhances XBP1 mRNA splicing and expression of its target genes, associated with attenuated apoptosis under ER stress conditions. Inhibition of XBP1 mRNA splicing either by dominant negative IRE1alpha or by knocking down XBP1 specifically abrogated the inhibition of ER stress-induced apoptosis by Hsp72. Regulation of the UPR was associated with the formation of a stable protein complex between Hsp72 and the cytosolic domain of IRE1alpha. Finally, Hsp72 enhanced the RNase activity of recombinant IRE1alpha in vitro, suggesting a direct regulation. Our data show that binding of Hsp72 to IRE1alpha enhances IRE1alpha\\/XBP1 signaling at the ER and inhibits ER stress-induced apoptosis. These results provide a physical connection between cytosolic chaperones and the ER stress response.

  19. HSP72 protects cells from ER stress-induced apoptosis via enhancement of IRE1alpha-XBP1 signaling through a physical interaction.

    Directory of Open Access Journals (Sweden)

    Sanjeev Gupta

    2010-07-01

    Full Text Available Endoplasmic reticulum (ER stress is a feature of secretory cells and of many diseases including cancer, neurodegeneration, and diabetes. Adaptation to ER stress depends on the activation of a signal transduction pathway known as the unfolded protein response (UPR. Enhanced expression of Hsp72 has been shown to reduce tissue injury in response to stress stimuli and improve cell survival in experimental models of stroke, sepsis, renal failure, and myocardial ischemia. Hsp72 inhibits several features of the intrinsic apoptotic pathway. However, the molecular mechanisms by which Hsp72 expression inhibits ER stress-induced apoptosis are not clearly understood. Here we show that Hsp72 enhances cell survival under ER stress conditions. The UPR signals through the sensor IRE1alpha, which controls the splicing of the mRNA encoding the transcription factor XBP1. We show that Hsp72 enhances XBP1 mRNA splicing and expression of its target genes, associated with attenuated apoptosis under ER stress conditions. Inhibition of XBP1 mRNA splicing either by dominant negative IRE1alpha or by knocking down XBP1 specifically abrogated the inhibition of ER stress-induced apoptosis by Hsp72. Regulation of the UPR was associated with the formation of a stable protein complex between Hsp72 and the cytosolic domain of IRE1alpha. Finally, Hsp72 enhanced the RNase activity of recombinant IRE1alpha in vitro, suggesting a direct regulation. Our data show that binding of Hsp72 to IRE1alpha enhances IRE1alpha/XBP1 signaling at the ER and inhibits ER stress-induced apoptosis. These results provide a physical connection between cytosolic chaperones and the ER stress response.

  20. Resveratrol enhances palmitate-induced ER stress and apoptosis in cancer cells.

    Directory of Open Access Journals (Sweden)

    Cristina Rojas

    Full Text Available Palmitate, a saturated fatty acid (FA, is known to induce toxicity and cell death in various types of cells. Resveratrol (RSV is able to prevent pathogenesis and/or decelerate the progression of a variety of diseases. Several in vitro and in vivo studies have also shown a protective effect of RSV on fat accumulation induced by FAs. Additionally, endoplasmic reticulum (ER stress has recently been linked to cellular adipogenic responses. To address the hypothesis that the RSV effect on excessive fat accumulation promoted by elevated saturated FAs could be partially mediated by a reduction of ER stress, we studied the RSV action on experimentally induced ER stress using palmitate in several cancer cell lines.We show that, unexpectedly, RSV promotes an amplification of palmitate toxicity and cell death and that this mechanism is likely due to a perturbation of palmitate accumulation in the triglyceride form and to a less important membrane fluidity variation. Additionally, RSV decreases radical oxygen species (ROS generation in palmitate-treated cells but leads to enhanced X-box binding protein-1 (XBP1 splicing and C/EBP homologous protein (CHOP expression. These molecular effects are induced simultaneously to caspase-3 cleavage, suggesting that RSV promotes palmitate lipoapoptosis primarily through an ER stress-dependent mechanism. Moreover, the lipotoxicity reversion induced by eicosapentaenoic acid (EPA or by a liver X receptor (LXR agonist reinforces the hypothesis that RSV-mediated inhibition of palmitate channeling into triglyceride pools could be a key factor in the aggravation of palmitate-induced cytotoxicity.Our results suggest that RSV exerts its cytotoxic role in cancer cells exposed to a saturated FA context primarily by triglyceride accumulation inhibition, probably leading to an intracellular palmitate accumulation that triggers a lipid-mediated cell death. Additionally, this cell death is promoted by ER stress through a CHOP

  1. Emodin enhances ATRA-induced differentiation and induces apoptosis in acute myeloid leukemia cells.

    Science.gov (United States)

    Chen, Yingyu; Li, Jing; Hu, Jianda; Zheng, Jing; Zheng, Zhihong; Liu, Tingbo; Lin, Zhenxing; Lin, Minhui

    2014-11-01

    Emodin, an extracted natural compound from the root and rhizome of Rheum palmatum L, has been shown to have multiple biological activities including anticancer functions in previous studies. In this study, we investigated the anti-leukemic activity of emodin alone or emodin in the presence all-trans retinoic acid (ATRA) in acute myeloid leukemia (AML) cells and the potential signaling pathway involved. We demonstrated that emodin could significantly enhance the sensitivity to ATRA and present additive differentiation-inducing effects in AML cell line NB4 cells and, especially, in NB4-derived ATRA-resistant MR2 cells. Further study showed that increasing dose of emodin could effectively induce growth inhibition and apoptotic effects in both cell lines as well as in primary leukemic cells from AML patients. Moreover, the apoptotic induction in AML cells was associated with the activation of caspase cascades involving caspase-9, caspase-3, and poly(ADP-ribose) polymerase (PARP) cleavage. In addition, leukemic cell response to emodin stimuli in vitro was observed through the decreased expression levels of Bcl-2 and retinoic acid receptor α (RARα). Importantly, emodin was demonstrated as a new inhibitor of PI3K/Akt in AML cells, even in primary AML cells. It inhibited Akt phosphoration (p-Akt) at Ser473 as efficiently as mTOR at Ser2448. Consistently, it exerted suppression effects on the phosphoration of mTOR downstream targets, 4E-BP1 and p70S6K. Taken together, these findings indicate that emodin might be developed as a promising anti-leukemic agent to improve the patient outcome in AML.

  2. Antcin B and its ester derivative from Antrodia camphorata induce apoptosis in hepatocellular carcinoma cells involves enhancing oxidative stress coincident with activation of intrinsic and extrinsic apoptotic pathway.

    Science.gov (United States)

    Hsieh, Yun-Chih; Rao, Yerra Koteswara; Whang-Peng, Jacqueline; Huang, Chi-Ying F; Shyue, Song-Kun; Hsu, Shih-Lan; Tzeng, Yew-Min

    2011-10-26

    The triterpenoids methylantcinate B (MAB) and antcin B (AB), isolated from the medicinal mushroom Antrodia camphorata , have been identified as strong cytotoxic agents against various type of cancer cells; however, the mechanisms of MAB- and AB-induced cytotoxicity have not been adequately explored. This study investigated the roles of caspase cascades, reactive oxygen species (ROS), DNA damage, mitochondrial disruption, and Bax and Bcl-2 proteins in MAB- and AB-induced apoptosis of hepatocellular carcinoma (HCC) HepG2 cells. Here, we showed that MAB and AB induced apoptosis in HepG2 cells, as characterized by increased DNA fragmentation, cleavage of PARP, sub-G1 population, chromatin condensation, loss of mitochondrial membrane potential, and release of cytochrome c. Increasing the levels of caspase-2, -3, -8, and -9 activities was involved in MAB- and AB-induced apoptosis, and they could be attenuated by inhibitors of specific caspases, indicating that MAB and AB triggered the caspase-dependent apoptotic pathway. Additionally, the enhanced apoptotic effect correlates with high expression of Fas, Fas ligand, as well as Bax and decreased protein levels of Bcl-(XL) and Bcl-2, suggesting that both the extrinsic and intrinsic apoptosis pathways were involved in the apoptotic processes. Incubation of HepG2 cells with antioxidant enzymes superoxide dismutase and catalase and antioxidants N-acetylcysteine and ascorbic acid attenuated the ROS generation and apoptosis induced by MAB and AB, which indicate that ROS plays a pivotal role in cell death. NADPH oxidase activation was observed in MAB- and AB-stimulated HepG2 cells; however, inhibition of such activation by diphenylamine significantly blocked MAB- and AB-induced ROS production and increased cell viability. Taken together, our results provide the first evidence that triterpenoids MAB and AB induced a NADPH oxidase-provoked oxidative stress and extrinsic and intrinsic apoptosis as a critical mechanism of cause cell

  3. Sequential combination of docetaxel with a SHP-1 agonist enhanced suppression of p-STAT3 signaling and apoptosis in triple negative breast cancer cells.

    Science.gov (United States)

    Liu, Chun-Yu; Chen, Kuen-Feng; Chao, Tzu-I; Chu, Pei-Yi; Huang, Chun-Teng; Huang, Tzu-Ting; Yang, Hsiu-Ping; Wang, Wan-Lun; Lee, Chia-Han; Lau, Ka-Yi; Tsai, Wen-Chun; Su, Jung-Chen; Wu, Chia-Yun; Chen, Ming-Huang; Shiau, Chung-Wai; Tseng, Ling-Ming

    2017-06-04

    Triple negative breast cancer (TNBC) is an aggressive cancer for which prognosis remains poor. Combination therapy is a promising strategy for enhancing treatment efficacy. Blockade of STAT3 signaling may enhance the response of cancer cells to conventional chemotherapeutic agents. Here we used a SHP-1 agonist SC-43 to dephosphorylate STAT3 thereby suppressing oncogenic STAT3 signaling and tested it in combination with docetaxel in TNBC cells. We first analyzed messenger RNA (mRNA) expression of SHP-1 gene (PTPN6) in a public TNBC dataset (TCGA) and found that higher SHP-1 mRNA expression is associated with better overall survival in TNBC patients. Sequential combination of docetaxel and SC-43 in vitro showed enhanced anti-proliferation and apoptosis associated with decreased p-STAT3 and decreased STAT3-downstream effector cyclin D1 in the TNBC cell lines MDA-MB-231, MDA-MB-468, and HCC-1937. Ectopic expression of STAT3 reduced the increased cytotoxicity induced by the combination therapy. In addition, this sequential combination showed enhanced SHP-1 activity compared to SC-43 alone. Furthermore, the combination treatment-induced apoptosis was attenuated by small interfering RNA (siRNA) against SHP-1 or by ectopic expression of SHP-1 mutants that caused SC-43 to lose its SHP-1 agonist capability. Moreover, combination of docetaxel and SC-43 showed enhanced tumor growth inhibition compared to single-agent therapy in mice bearing MDA-MB-231 tumor xenografts. Our results suggest that the novel SHP-1 agonist SC-43 enhanced docetaxel-induced cytotoxicity by SHP-1 dependent STAT3 inhibition in human triple negative breast cancer cells. TNBC patients with high SHP-1 expressions show better survival. Docetaxel combined with SC-43 enhances cell apoptosis and reduces p-STAT3. SHP-1 inhibition reduces the enhanced effect of docetaxel-SC-43 combination. Docetaxel-SC-43 combination suppresses xenograft tumor growth and reduces p-STAT3. TNBC patients with high SHP-1 expressions

  4. HA14-1 selectively induces apoptosis in Bcl-2-overexpressing leukemia/lymphoma cells, and enhances cytarabine-induced cell death.

    Science.gov (United States)

    Lickliter, J D; Wood, N J; Johnson, L; McHugh, G; Tan, J; Wood, F; Cox, J; Wickham, N W

    2003-11-01

    The Bcl-2 oncoprotein is commonly overexpressed in hematological malignancy, where it promotes the survival of neoplastic cells. Recently, a small molecule (HA14-1) was reported to bind the surface pocket of Bcl-2 that mediates antiapoptotic interactions, triggering apoptosis in a Bcl-2-transfected cell line. We investigated the activity of this compound in a panel of malignant hematopoietic cell lines. Consistent with its proposed role as a Bcl-2 inhibitor, HA14-1 was most cytotoxic in lines expressing high levels of Bcl-2. In addition, at lower concentrations (5-12.5 muM), the compound predominantly triggered apoptosis. However, at concentrations two-fold higher than this and above, increasing primary necrosis was observed, suggesting the onset of interactions supplementary to Bcl-2 inhibition. In experiments on primary cells, 25 muM HA14-1 induced extensive apoptosis in acute leukemic blasts, but also suppressed normal hematopoietic colony formation to <50% of baseline. Importantly, low-concentration HA14-1 (5 muM) was nontoxic to normal colony-forming cells, whereas it enhanced the cytotoxicity of the antileukemia drug cytarabine in Bcl-2-positive lymphoblastic leukemia cells. In conclusion, our results indicate that HA14-1 at low concentration selectively triggers apoptosis in malignant hematopoietic cells that overexpress Bcl-2. Agents of this class may have particular utility in combination with cytotoxic chemotherapy drugs.

  5. Myricetin and methyl eugenol combination enhances the anticancer activity, cell cycle arrest and apoptosis induction of cis-platin against HeLa cervical cancer cell lines.

    Science.gov (United States)

    Yi, Jin-Ling; Shi, Song; Shen, Yan-Li; Wang, Ling; Chen, Hai-Yan; Zhu, Jun; Ding, Yan

    2015-01-01

    Drug combination therapies are common practice in the treatment of cancer. In this study, we evaluated the anticancer effects of myricetin (MYR), methyl eugenol (MEG) and cisplatin (CP) both separately as well as in combination against cervical cancer (HeLa) cells. To demonstrate whether MYR and MEG enhance the anticancer activity of CP against cervical cancer cells, we treated HeLa cells with MYR and MEG alone or in combination with cisplatin and evaluated cell growth and apoptosis using MTT (3 (4, 5 dimethyl thiazol 2yl) 2, 5 diphenyltetrazolium bromide) assay, LDH release assay, flow cytometry and fluorescence microscopy. The results revealed that, as compared to single drug treatment, the combination of MYR or MEG with CP resulted in greater effect in inhibiting cancer cell growth and inducing apoptosis. Cell apoptosis induction, Caspase-3 activity, cell cycle arrest and mitochondrial membrane potential loss were systematically studied to reveal the mechanisms of synergy between MYR, MEG and CP. Combination of MYR or MEG with CP resulted in more potent apoptosis induction as revealed by fluorescence microscopy using Hoechst 33258 and AO-ETBR staining. The combination treatment also increased the number of cells in G0/G1 phase dramatically as compared to single drug treatment. Mitochondrial membrane potential loss (ΛΨm) as well as Caspase-3 activity was much higher in combination treatment as compared to single drug treatment. Findings of this investigation suggest that MYR and MEG combined with cisplatin is a potential clinical chemotherapeutic approach in human cervical cancer.

  6. Heme oxygenase-1 prevents cardiac dysfunction in streptozotocin-diabetic mice by reducing inflammation, oxidative stress, apoptosis and enhancing autophagy

    National Research Council Canada - National Science Library

    Zhao, Yanli; Zhang, Lina; Qiao, Yu; Zhou, Xiaoling; Wu, Guodong; Wang, Lujing; Peng, Yahui; Dong, Xingli; Huang, Hui; Si, Lining; Zhang, Xueying; Zhang, Lei; Li, Jihong; Wang, Wei; Zhou, Lingyun; Gao, Xu

    2013-01-01

    Heme oxygenase-1 (HO-1) has been implicated in cardiac dysfunction, oxidative stress, inflammation, apoptosis and autophagy associated with heart failure, and atherosclerosis, in addition to its recognized role in metabolic...

  7. Osthole enhances TRAIL-mediated apoptosis through downregulation of c-FLIP expression in renal carcinoma Caki cells.

    Science.gov (United States)

    Min, Kyoung-Jin; Han, Min Ae; Kim, Shin; Park, Jong-Wook; Kwon, Taeg Kyu

    2017-04-01

    Osthole, an active constituent isolated from the fruit of Cnidium monnieri (L.) Cusson, has been shown to induce various beneficial biochemical effects such as anti-inflammatory and antitumor. In the present study, we examined whether osthole could sensitize TNF-related apoptosis-inducing ligand (TRAIL)-induced apoptosis in human renal carcinoma Caki cells. We found that osthole and TRAIL alone, had no effect on apoptosis, but combined treatment with osthole and TRAIL markedly induced apoptosis in Caki (renal carcinoma), U251MG (glioma) and MDA-MB-231 (breast carcinoma) cells. In contrast, combined treatment with osthole and TRAIL did not induce apoptosis in normal human skin fibroblast cells. Osthole induced downregulation of cellular FLICE-like inhibitory protein (c-FLIP) expression, and overexpression of c-FLIP markedly blocked apoptosis induced by the combined treatment with osthole and TRAIL. In addition, osthole markedly reduced mitochondrial membrane potential levels, and increased cytosolic cytochrome c release in combined treatment with osthole and TRAIL. Therefore, these data suggest that osthole may be an efficient TRAIL sensitizer.

  8. Down-regulation of liver-intestine cadherin enhances noscapine-induced apoptosis in human colon cancer cells.

    Science.gov (United States)

    Tian, Xia; Liu, Meng; Zhu, Qingxi; Tan, Jie; Liu, Weijie; Wang, Yanfen; Chen, Wei; Zou, Yanli; Cai, Yishan; Han, Zheng; Huang, Xiaodong

    2017-09-01

    The aim of the present study was to explore the signaling pathway of noscapine which induces apoptosis by blocking liver-intestine cadherin (CDH17) gene in colon cancer SW480 cells. Human colon cancer SW480 cells were transfected with CDH17 interference vector and treatment with 10 µmol/L noscapine. The proliferation and apoptosis of SW480 cells were detected by MTT assay and AnnexinV-FITC/PI flow cytometry kit (BD), respectively. Cell invasion were assessed by transwell assays. Apoptosis related proteins (Cyt-c, Bax, Bcl-2 and Bcl-xL) levels were evaluated by western blot. Compared to the noscapine group, the proliferation was decreased significantly and the apoptosis was increased significantly in SW480 cells of the siCDH17+noscapine group. Cyt-c and Bax protein levels in siCDH17+noscapine group was higher than that of the noscapine group, but Bcl-2 and Bcl-xL protein levels in siCDH17+noscapine group were lower than that of the noscapine group. Moreover, up-expression of CDH17 inhibited the efficacy of noscapine-induced apoptosis in SW480 cells. We inferred that down-expression of extrinsic CDH17 gene can conspicuously promote apoptosis-inducing effects of noscapine on human colon cancer SW480 cells, which is a novel strategy to improve chemotherapeutic effects on colon cancer.

  9. Enhanced T-cell apoptosis in human septic shock is associated with alteration of the costimulatory pathway.

    Science.gov (United States)

    Roger, P-M; Hyvernat, H; Breittmayer, J-P; Dunais, B; Dellamonica, J; Bernardin, G; Bernard, A

    2009-06-01

    T-cell apoptosis during septic shock (SS) has been associated with deleterious outcome, but the mechanisms of apoptosis are not well understood. As T-cells are not infected in bacterial infection, our hypothesis was that deleterious interactions between lymphocytes and monocytes could be involved. This is a cross-sectional study of 27 patients presenting with community-acquired SS, 23 infected patients without SS and 18 controls. Cytofluorometric techniques were used to study apoptosis, the costimulatory pathway and cytokine synthesis. Apoptosis was increased in SS compared to infected patients without SS and controls: the median values were 18, 2 and 3%, respectively, for CD4(+) T-cells (P < 0.001), and 12, 5 and 2%, respectively, for CD8(+) T-cells (P < 0.001). Patients with SS exhibited significant CD152 over-expression on T-cells, while CD86 expression was decreased on monocytes (P = 0.004). The synthesis of interleukin-2 was decreased in patients with SS compared to the other groups, while secretions of interferon-gamma and TNF-alpha were not altered. Ten surviving patients with SS showed a trend towards the normalisation of these parameters on day 7. In SS, T-cell apoptosis is related, at least in part, to the alteration of the costimulatory pathway, which, in turn, leads to significant modification of the cytokine network.

  10. GRP78 knockdown enhances apoptosis via the down-regulation of oxidative stress and Akt pathway after epirubicin treatment in colon cancer DLD-1 cells.

    Directory of Open Access Journals (Sweden)

    Yu-Jia Chang

    Full Text Available INTRODUCTION: The 78-kDa glucose-regulated protein (GRP78 is induced in the cancer microenvironment and can be considered as a novel predictor of responsiveness to chemotherapy in many cancers. In this study, we found that intracellular reactive oxygen species (ROS and nuclear factor erythroid 2-related factor 2 (Nrf2 nuclear translocation were higher in GRP78 knockdown DLD-1 colon cancer cells compared with scrambled control cells. METHODOLOGY/PRINCIPAL FINDINGS: Treatment with epirubicin in GRP78 knockdown DLD-1 cells enhanced apoptosis and was associated with decreased production of intracellular ROS. In addition, apoptosis was increased by the antioxidants propyl gallate (PG and dithiothreitol (DTT in epirubicin-treated scrambled control cells. Epirubicin-treated GRP78 knockdown cells resulted in more inactivated Akt pathway members, such as phosphorylated Akt and GSK-3β, as well as downstream targets of β-catenin expression. Knockdown of Nrf2 with small interfering RNA (siRNA increased apoptosis in epirubicin-treated GRP78 knockdown cells, which suggested that Nrf2 may be a primary defense mechanism in GRP78 knockdown cells. We also demonstrated that epirubicin-treated GRP78 knockdown cells could decrease survival pathway signaling through the redox activation of protein phosphatase 2A (PP2A, which is a serine/threonine phosphatase that negatively regulates the Akt pathway. CONCLUSIONS: Our results indicate that epirubicin decreased the intracellular ROS in GRP78 knockdown cells, which decreased survival signaling through both the Akt pathway and the activation of PP2A. Together, these mechanisms contributed to the enhanced level of epirubicin-induced apoptosis that was observed in the GRP78 knockdown cells.

  11. RGD-avidin–biotin pretargeting to αvβ3 integrin enhances the proapoptotic activity of TNFα related apoptosis inducing ligand (TRAIL)

    Science.gov (United States)

    Tarrus, Marc; van der Sloot, Almer M.; Temming, Kai; Lacombe, Marie; Opdam, Frank; Quax, Wim J.; Molema, Grietje; Poelstra, Klaas

    2007-01-01

    Recombinant TNF-related apoptosis-inducing ligand (TRAIL) is considered a powerful and selective inducer of tumor cell death. We hypothesize that TRAIL’s potential as anticancer agent can be enhanced further by promoting its accumulation in tumor tissue. For this purpose, we developed TRAIL complexes that bind to angiogenic endothelial cells. We employed an avidin–biotin pretargeting approach, in which biotinylated TRAIL interacted with RGD-equipped avidin. The assembled complexes killed tumor cells (Jurkat T cells) via apoptosis induction. Furthermore, we demonstrated that the association of the RGD-avidin-TRAIL complex onto endothelial cells enhanced the tumor cell killing activity. Endothelial cells were not killed by TRAIL nor its derived complexes. Our approach can facilitate the enrichment of TRAIL onto angiogenic blood vessels, which may enhance intratumoral accumulation. Furthermore, it offers a versatile technology for the complexation of targeting ligands with therapeutic recombinant proteins and by this a novel way to enhance their specificity and activity. PMID:18071905

  12. Inhibition of mitogen-activated protein kinase kinase enhances apoptosis induced by arsenic trioxide in human breast cancer MCF-7 cells.

    Science.gov (United States)

    Ye, Jian; Li, Aiping; Liu, Qizhan; Wang, Xinru; Zhou, Jianwei

    2005-12-01

    Arsenic trioxide (As2O3) has recently been used to treat acute promyelocytic leukaemia and has activity in vitro against several solid tumour cell lines where the induction of differentiation and apoptosis are the prime effects. The mechanism of As2O3-induced cell death has yet to be clarified, especially in solid cancers. In the present study, the human breast cancer cell line MCF-7 was examined as a cellular model for As2O3 treatment. The involvement of extracellular signal-regulated kinase (ERK), p38 and c-Jun N-terminal kinase (JNK) was investigated in As2O3-induced cell death. 3. It was found that As2O3 activates the prosurvival mitogen-activated protein kinase kinase (MEK)/ERK pathway in MCF-7 cells, which, conversely, may compromise the efficacy of As2O3. Hence, a combination treatment of As2O3 and MEK inhibitors was investigated to determine whether this treatment could lead to enhanced growth inhibition and apoptosis in MCF-7 cells. 4. Inhibition of MEK/ERK with the pharmacological inhibitors U0126 (10 micromol/L) or PD98059 (20 micromol/L) together with As2O3 (2 and 5 micromol/L) resulted in a significant enhancement of growth inhibition in breast cancer MCF-7 cells as determined by the 3-(4,5-dimethyl-2 thiazoyl)-2,5-diphenyl-2H-tetrazolium bromide assay and [Methyl-3H]-thymidine incorporation. Furthermore, the results demonstrated that combined treatment with As2O3 and the MEK1/2 inhibitor U0126 could augment breast cancer MCF-7 cell apoptosis approximately twofold compared with the effects of the two drugs alone, as determined by Hoechst 33258 or annexin V/propidium iodide (PI) staining and flow cytometry. 5. In addition, As2O3 activated p38 in a dose-dependent manner, but had no effect on JNK1/2. Treatment with a p38 inhibitor did not prevent As2O3-induced apoptosis. 6. In conclusion, the results of the present study showed that enhanced apoptosis is detected in breast cancer MCF-7 cells in the presence of As2O3 and an MEK inhibitor, which may be a

  13. SiRNA knockdown of the DEK nuclear protein mRNA enhances apoptosis and chemosensitivity of canine transitional cell carcinoma cells.

    Science.gov (United States)

    Yamazaki, Hiroki; Iwano, Tomomi; Otsuka, Saori; Kagawa, Yumiko; Hoshino, Yuki; Hosoya, Kenji; Okumura, Masahiro; Takagi, Satoshi

    2015-04-01

    Transitional cell carcinoma (TCC) in dogs is an aggressive malignant neoplasm, originating in the epithelium of the urinary bladder. The DEK nuclear protein is overexpressed in several types of human bladder cancer, where it is involved in chromatin reconstruction, gene transcription and apoptosis. Since DEK represents a potential therapeutic target for canine TCC, this study was designed to investigate DEK expression in canine TCC and to determine the effects of DEK mRNA silencing on TCC cells in vitro. The gene expression profiles of seven selected cancer-associated genes was assessed in four canine TCC cell lines and expression of DEK protein was evaluated in bladder tissue biopsies from healthy dogs and those affected with cystitis or TCC. After transfection of four canine TCC cell lines with DEK-specific or scrambled siRNA, annexin V staining was performed to evaluate apoptosis, and methylthiazole tetrazolium assays were performed to assess both cell viability and sensitivity to carboplatin. DEK mRNA expression was relatively high in canine TCC cells and expression of the DEK protein was significantly greater in TCC tumours compared with the other tissue samples. After transfection with DEK-specific siRNA, apoptosis, cell growth inhibition, and enhanced sensitivity to carboplatin were observed in all TCC cells assessed. These research findings suggest that DEK could be a potential therapeutic target for canine TCC. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. MiR-124 Inhibits Growth and Enhances Radiation-Induced Apoptosis in Non-Small Cell Lung Cancer by Inhibiting STAT3

    Directory of Open Access Journals (Sweden)

    Mengjie Wang

    2017-12-01

    Full Text Available Background/Aims: A growing body of evidence indicates that the abnormal expression of microRNAs (miRNAs play an important role in sensitizing the cellular response to ionizing radiation (IR. The aim of this study was to investigate whether the expression of miR-124 correlated with radiosensitivity in the context of non-small-cell lung carcinoma (NSCLC. Methods: Quantitative reverse transcription polymerase chain reaction (RT-PCR was used to quantify miR-124 expression in NSCLC tissues and cell lines. The role of miR-124 in NSCLC proliferation and radiosensitivity was analyzed using CCK-8 and flow cytometry apoptosis assays. Luciferase activity assays, RT-PCR, and Western blot assays were performed to confirm the target gene of miR-124. Results: In this study, we found that miR-124 was downregulated both in clinical NSCLC samples and in cell lines. miR-124 inhibited the proliferation of NSCLC cells and enhanced the apoptosis of NSCLC cells exposed to ionizing radiation. We identified signal transducer and activator of transcription 3 (STAT3 as a direct target of miR-124 by using target prediction algorithms and luciferase assays. Overexpression of STAT3 in A549 cell lines restored the enhanced radiosensitivity induced by miR-124. Conclusion: Taking these observations into consideration, we illustrated that miR-124 is a potential target for enhancing the radiosensitivity of NSCLC cells by targeting STAT3.

  15. Autophagy Inhibition Enhances the Mitochondrial-Mediated Apoptosis Induced by Mangrove (Avicennia marina) Extract in Human Breast Cancer Cells

    KAUST Repository

    Esau, Luke

    2015-01-10

    Aims: Avicennia marina (AM) is a widely distributed mangrove plant that has been used in traditional medicine for centuries for the treatment of a number of diseases. The objective of the present study was to evaluate the leaf ethyl acetate extract of AM for its cytotoxic and apoptotic potential along with in-depth investigations of its mechanism of action in breast cancer MCF-7 cells. Study Design: The ethyl acetate extract of leaves and stems of AM was tested against estrogen positive breast cancer cell line MCF-7 using various assays. Place and Duration of Study: The study was carried out at King Abdullah University of Science and Technology, Thuwal, Saudi Arabia, from July 2013-June 2014. Methodology: Dose- and time-dependent growth inhibition of cancer cells was measured using MTT assay. The mechanisms of apoptosis induction were determined using various assays: phosphatidylserine exposure, caspase-3/7 activation, mitochondrial membrane potential disruption, reactive oxygen species (ROS) production, cell cycle analysis, autophagy, and protein expression using western blotting. The modulation of apoptotic genes (p53, Mdm2, NF-kB, Bad, Bax, Bcl-2 and Casp7) was also determined using real time PCR. Results: The AM extract inhibited breast cancer cell growth and induced apoptosis in a concentration dependent manner. We demonstrated a non-classical mode of apoptosis induction in MCF-7 cells by AM extract, where ROS production altered the mitochondrial membrane potential to induce apoptosis. Breast cancer cells treated with 200 µg/ml concentration of AM extract showed increased ROS production and disrupted MMP but no PARP-1 cleavage and a marked decrease in Caspase-7 protein levels (24 and 48 h) were detected. A significant amount of autophagy was also observed at the same concentration. However, treatment of MCF-7 cells with 200 µg/ml of AM extract along with the inhibition of autophagy by chloroquine, significantly increased the apoptosis from 20% to 45

  16. Nanoparticle Delivery of Artesunate Enhances the Anti-tumor Efficiency by Activating Mitochondria-Mediated Cell Apoptosis

    Science.gov (United States)

    Liu, Rui; Yu, Xiwei; Su, Chang; Shi, Yijie; Zhao, Liang

    2017-06-01

    Artemisinin and its derivatives were considered to exert a broad spectrum of anti-cancer activities, and they induced significant anti-cancer effects in tumor cells. Artemisinin and its derivatives could be absorbed quickly, and they were widely distributed, selectively killing tumor cells. Since low concentrations of artesunate primarily depended on oncosis to induce cell death in tumor cells, its anti-tumor effects were undesirable and limited. To obtain better anti-tumor effects, in this study, we took advantage of a new nanotechnology to design novel artesunate-loaded bovine serum albumin nanoparticles to achieve the mitochondrial accumulation of artesunate and induce mitochondrial-mediated apoptosis. The results showed that when compared with free artesunate's reliance on oncotic death, artesunate-loaded bovine serum albumin nanoparticles showed higher cytotoxicity and their significant apoptotic effects were induced through the distribution of artesunate in the mitochondria. This finding indicated that artesunate-loaded bovine serum albumin nanoparticles damaged the mitochondrial integrity and activated mitochondrial-mediated cell apoptosis by upregulating apoptosis-related proteins and facilitating the rapid release of cytochrome C.

  17. Hydrostatic Compress Force Enhances the Viability and Decreases the Apoptosis of Condylar Chondrocytes through Integrin-FAK-ERK/PI3K Pathway

    Directory of Open Access Journals (Sweden)

    Dandan Ma

    2016-11-01

    Full Text Available Reduced mechanical stimuli in many pathological cases, such as hemimastication and limited masticatory movements, can significantly affect the metabolic activity of mandibular condylar chondrocytes and the growth of mandibles. However, the molecular mechanisms for these phenomena remain unclear. In this study, we hypothesized that integrin-focal adhesion kinase (FAK-ERK (extracellular signal–regulated kinase/PI3K (phosphatidylinositol-3-kinase signaling pathway mediated the cellular response of condylar chondrocytes to mechanical loading. Primary condylar chondrocytes were exposed to hydrostatic compressive forces (HCFs of different magnitudes (0, 50, 100, 150, 200, and 250 kPa for 2 h. We measured the viability, morphology, and apoptosis of the chondrocytes with different treatments as well as the gene, protein expression, and phosphorylation of mechanosensitivity-related molecules, such as integrin α2, integrin α5, integrin β1, FAK, ERK, and PI3K. HCFs could significantly increase the viability and surface area of condylar chondrocytes and decrease their apoptosis in a dose-dependent manner. HCF of 250 kPa resulted in a 1.51 ± 0.02-fold increase of cell viability and reduced the ratio of apoptotic cells from 18.10% ± 0.56% to 7.30% ± 1.43%. HCFs could significantly enhance the mRNA and protein expression of integrin α2, integrin α5, and integrin β1 in a dose-dependent manner, but not ERK1, ERK2, or PI3K. Instead, HCF could significantly increase phosphorylation levels of FAK, ERK1/2, and PI3K in a dose-dependent manner. Cilengitide, the potent integrin inhibitor, could dose-dependently block such effects of HCFs. HCFs enhances the viability and decreases the apoptosis of condylar chondrocytes through the integrin-FAK-ERK/PI3K pathway.

  18. Equol enhances tamoxifen’s anti-tumor activity by induction of caspase-mediated apoptosis in MCF-7 breast cancer cells

    Science.gov (United States)

    2013-01-01

    Background Soy phytoestrogens, such as daidzein and its metabolite equol, have been proposed to be responsible for the low breast cancer rate in Asian women. Since the majority of estrogen receptor positive breast cancer patients are treated with tamoxifen, the basic objective of this study is to determine whether equol enhances tamoxifen’s anti-tumor effect, and to identify the molecular mechanisms involved. Methods For this purpose, we examined the individual and combined effects of equol and tamoxifen on the estrogen-dependent MCF-7 breast cancer cells using viability assays, annexin-V/PI staining, cell cycle and western blot analysis. Results We found that equol (>50 μM) and 4-hydroxy-tamoxifen (4-OHT; >100 nM) significantly reduced the MCF-7 cell viability. Furthermore, the combination of equol (100 μM) and 4-OHT (10 μM) induced apoptosis more effectively than each compound alone. Subsequent treatment of MCF-7 cells with the pan-caspase inhibitor Z-VAD-FMK inhibited equol- and 4-OHT-mediated apoptosis, which was accompanied by PARP and α-fodrin cleavage, indicating that apoptosis is mainly caspase-mediated. These compounds also induced a marked reduction in the bcl-2:bax ratio, which was accompanied by caspase-9 and caspase-7 activation and cytochrome-c release to the cytosol. Taken together, these data support the notion that the combination of equol and tamoxifen activates the intrinsic apoptotic pathway more efficiently than each compound alone. Conclusions Consequently, equol may be used therapeutically in combination treatments and clinical studies to enhance tamoxifen’s effect by providing additional protection against estrogen-responsive breast cancers. PMID:23675643

  19. Pharmacological Administration of the Isoflavone Daidzein Enhances Cell Proliferation and Reduces High Fat Diet-Induced Apoptosis and Gliosis in the Rat Hippocampus

    Science.gov (United States)

    Rivera, Patricia; Pérez-Martín, Margarita; Pavón, Francisco J.; Serrano, Antonia; Crespillo, Ana; Cifuentes, Manuel; López-Ávalos, María-Dolores; Grondona, Jesús M.; Vida, Margarita; Fernández-Llebrez, Pedro; de Fonseca, Fernando Rodríguez; Suárez, Juan

    2013-01-01

    Soy extracts have been claimed to be neuroprotective against brain insults, an effect related to the estrogenic properties of isoflavones. However, the effects of individual isoflavones on obesity-induced disruption of adult neurogenesis have not yet been analyzed. In the present study we explore the effects of pharmacological administration of daidzein, a main soy isoflavone, in cell proliferation, cell apoptosis and gliosis in the adult hippocampus of animals exposed to a very high-fat diet. Rats made obese after 12-week exposure to a standard or high-fat (HFD, 60%) diets were treated with daidzein (50 mg kg−1) for 13 days. Then, plasma levels of metabolites and metabolic hormones, cell proliferation in the subgranular zone of the dentate gyrus (SGZ), and immunohistochemical markers of hippocampal cell apoptosis (caspase-3), gliosis (GFAP and Iba-1), food reward factor FosB and estrogen receptor alpha (ERα) were analyzed. Treatment with daidzein reduced food/caloric intake and body weight gain in obese rats. This was associated with glucose tolerance, low levels of HDL-cholesterol, insulin, adiponectin and testosterone, and high levels of leptin and 17β-estradiol. Daidzein increased the number of phospho-histone H3 and 5-bromo-2-deoxyuridine (BrdU)-ir cells detected in the SGZ of standard diet and HFD-fed rats. Daidzein reversed the HFD-associated enhanced immunohistochemical expression of caspase-3, FosB, GFAP, Iba-1 and ERα in the hippocampus, being more prominent in the dentate gyrus. These results suggest that pharmacological treatment with isoflavones regulates metabolic alterations associated with enhancement of cell proliferation and reduction of apoptosis and gliosis in response to high-fat diet. PMID:23741384

  20. Granulocyte-Colony Stimulating Factor (G-CSF) Accelerates Wound Healing in Hemorrhagic Shock Rats by Enhancing Angiogenesis and Attenuating Apoptosis

    Science.gov (United States)

    Huang, Hong; Zhang, Qi; Liu, Jiejie; Hao, Haojie; Jiang, Chaoguang; Han, Weidong

    2017-01-01

    Background Following severe trauma, treatment of cutaneous injuries is often delayed by inadequate blood supply. The aim of the present study was to determine whether granulocyte-colony stimulating factor (G-CSF) protects endothelial cells (ECs) and enhances angiogenesis in a rat model of hemorrhagic shock (HS) combined with cutaneous injury after resuscitation. Material/Methods The HS rats with full-thickness defects were resuscitated and randomly divided into a G-CSF group (200 μg/kg body weight), a normal saline group, and a blank control group. Histological staining was to used estimate the recovery and apoptosis of skin. Apoptosis- and angiogenesis-related factors were analyzed by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot (WB). Scratch assay, tube formation, and WB experiments were performed to verify the functional effects of G-CSF on HUVECs in vitro. Results H&E staining and Masson trichrome staining showed earlier inflammation resolution and collagen synthesis in the G-CSF-treated group. Angiogenesis-related factors were elevated at mRNA and protein levels. TUNEL staining suggested fewer apoptotic cells in the G-CSF group. The apoptotic-related factors were down-regulated and anti-apoptotic factors were up-regulated in the G-CSF-treated group. Scratch assay and tube formation experiments revealed that G-CSF facilitated migration ability and angiogenic potential of HUVECs. The angiogenic and anti-apoptotic effects were also enhanced in vitro. Conclusions Our results suggest that G-CSF after resuscitation attenuates local apoptosis and accelerates angiogenesis. These findings hold great promise for improving therapy for cutaneous injury in severe trauma and ischemia diseases. PMID:28559534

  1. ERK inhibition enhances TSA-induced gastric cancer cell apoptosis via NF-κB-dependent and Notch-independent mechanism.

    Science.gov (United States)

    Yao, Jun; Qian, Cui-Juan; Ye, Bei; Zhang, Xin; Liang, Yong

    2012-09-04

    To analyze the combined impact of the histone deacetylase inhibitor (HDACI) Trichostatin A (TSA) and the extracellular-signal-regulated kinase 1/2 (ERK1/2) inhibitor PD98059 on gastric cancer (GC) cell line SGC7901 growth. SGC7901 cells were treated with TSA, PD98059 or with a TSA-PD98059 combination. Effects of drug treatment on tumor cell proliferation, apoptosis, cell cycle progression, and cell signaling pathways were investigated by MTS assay, flow cytometry, Western blotting, chromatin immunoprecipitation (ChIP) assay, electrophoretic mobility shift assay (EMSA), and luciferase reporter assay, respectively. PD98059 enhanced TSA-induced cell growth arrest, apoptosis and activation of p21(WAF1/CIP1), but reversed TSA-induced activation of ERK1/2 and nuclear factor-κB (NF-κB). TSA alone up-regulated Notch1 and Hes1, and down-regulated Notch2, but PD98059 did not affect the trends of Notch1 and Notch2 induced by TSA. Particularly, PD98059 did potentiate the ability of TSA to down-regulate phospho-histone H3 protein, but increased levels of the acetylated forms of histone H3 bound to the p21(WAF1/CIP1) promoter, leading to enhanced expression of p21(WAF1/CIP1) in SGC7901 cells. PD98059 synergistically potentiates TSA-induced GC growth arrest and apoptosis by manipulating NF-κB and p21(WAF1/CIP1) independent of Notch. Therefore, concomitant administration of HDACIs and ERK1/2 inhibitors may be a promising treatment strategy for individuals with GC. Copyright © 2012 Elsevier Inc. All rights reserved.

  2. Ruthenium Polypyridyl Complex Inhibits Growth and Metastasis of Breast Cancer Cells by Suppressing FAK signaling with Enhancement of TRAIL-induced Apoptosis

    Science.gov (United States)

    Cao, Wenqiang; Zheng, Wenjie; Chen, Tianfeng

    2015-03-01

    Ruthenium-based complexes have emerged as promising antitumor and antimetastatic agents during the past decades. However, the limited understanding of the antimetastatic mechanisms of these agents is a roadblock to their clinical application. Herein, we reported that, RuPOP, a ruthenium polypyridyl complex with potent antitumor activity, was able to effectively inhibit growth and metastasis of MDA-MB-231 cells and synergistically enhance TRAIL-induced apoptosis. The selective intracellular uptake and cytotoxic effect of RuPOP was found associated with transferring receptor (TfR)-mediated endocytosis. Further investigation on intracellular mechanisms reveled that RuPOP notably suppressed FAK-mediated ERK and Akt activation. Pretreatment of cells with ERK inhibitor (U0126) and PI3K inhibitor (LY294002) significantly potentiated the inhibitory effect of RuPOP on cell growth, migration and invasion. Moreover, the alternation in the expression levels of metastatic regulatory proteins, including uPA, MMP-2/-9, and inhibition of VEGF secretion were also observed after RuPOP treatment. These results demonstrate the inhibitory effect of RuPOP on the growth and metastasis of cancer cells and the enhancement of TRAIL-induced apoptosis though suppression of FAK-mediated signaling. Furthermore, RuPOP exhibits the potential to be developed as a metal-based antimetastatic agent and chemosensitizer of TRAIL for the treatment of human metastatic cancers.

  3. Inecalcitol, an analog of 1,25D₃, displays enhanced antitumor activity through the induction of apoptosis in a squamous cell carcinoma model system

    Science.gov (United States)

    Ma, Yingyu; Yu, Wei-Dong; Hidalgo, Alejandro A.; Luo, Wei; Delansorne, Remi; Johnson, Candace S.; Trump, Donald L.

    2013-01-01

    Epidemiological data suggest an important role of vitamin D signaling in cancer development and progression, and experimental studies demonstrate that the active vitamin D metabolite 1α, 25-dihydroxyvitamin D₃ (1,25D₃) has broad spectrum antitumor activity. Hypercalcemia has often been suggested to limit the clinical application of these data. The 14-epi-analog of 1,25D₃, inecalcitol [19-nor-14-epi-23-yne-1,25-(OH)₂D₃; TX522], was developed to have superagonistic antitumor activities but low hypercalcemia potential. We examined the antitumor activity of inecalcitol and the underlying mechanisms in a murine squamous cell carcinoma (SCC) model system. In vitro, compared with 1,25D₃, inecalcitol showed enhanced vitamin D receptor (VDR)-mediated transcriptional activity. Inecalcitol suppressed SCC cell proliferation in a dose-dependent manner with an IC₅₀ value 30 times lower than that of 1,25D₃. Both inecalcitol and 1,25D₃ induced a comparable level of G₀/G₁ cell cycle arrest in SCC cells. The level of apoptosis induced by inecalcitol was markedly higher than that of 1,25D₃. Apoptosis was mediated through the activation of the caspase 8/10- caspase 3 pathway. Further, inecalcitol markedly inhibited the mRNA and protein expression of c-IAP1 and XIAP compared with 1,25D₃. In vivo, inecalcitol inhibits SCC tumor growth in a dose-dependent fashion. Notably, inecalcitol induced a significantly higher level of apoptosis in the SCC xenograft model. While in vitro inecalcitol demonstrates apparent enhanced VDR binding and antiproliferative effects compared to 1,25D₃, in vivo these advantages disappear; at doses of inecalcitol that have equivalent antitumor effects, similar hypercalcemia is seen. This may be explained by the pharmacokinetics of 1,25D₃ vs. inecalcitol and attributed to the much shorter serum half-life of inecalcitol.We show that inecalcitol has potent antitumor activity in the SCC model system, and this is associated with a

  4. MicroRNA-138 enhances TRAIL-induced apoptosis through interferon-stimulated gene 15 downregulation in hepatocellular carcinoma cells.

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    Zuo, Chaohui; Sheng, Xinyi; Liu, Zhuo; Ma, Min; Xiong, Shuhan; Deng, Hongyu; Li, Sha; Yang, Darong; Wang, Xiaohong; Xiao, Hua; Quan, Hu; Xia, Man

    2017-06-01

    Hepatocellular carcinoma is a leading cause of cancer-related mortality worldwide. TRAIL (tumor necrosis factor-related apoptosis-inducing ligand) is a potential target for cancer therapy. However, many cancer cells are resistant to TRAIL-induced apoptosis and its mechanism is not well understood. In this study, to identify potential therapeutic targets for TRAIL-resistant cancer cells, we compared the expression levels of interferon-stimulated gene 15 in TRAIL-sensitive and TRAIL-resistant hepatocellular carcinoma cell lines. Western blot analysis showed that interferon-stimulated gene 15 expression levels were significantly higher in resistant HLCZ01and Huh7 cells than in sensitive LH86 and SMMC-7721 cells. Interferon-stimulated gene 15 knockdown in resistance cells led to TRAIL sensitivity. Conversely, interferon-stimulated gene 15 overexpression in sensitive cells resulted in TRAIL resistance. Our bioinformatics search detected a putative target sequence for microRNA miR-138 in the 3' untranslated region of the interferon-stimulated gene 15. Real-time quantitative polymerase chain reaction analysis demonstrated that miR-138 was significantly downregulated in TRAIL-resistant cells compared to TRAIL-sensitive cells. Forced expression of miR-138 in resistant cells decreased both messenger RNA and protein levels of interferon-stimulated gene 15, and when exposed to TRAIL, activated poly(adenosine diphosphate-ribose) polymerase, indicating sensitization to TRAIL. The results suggested that miR-138 regulates the interferon-stimulated gene 15 expression by directly targeting the 3' untranslated region of interferon-stimulated gene 15 and modulates the sensitivity to TRAIL-induced apoptosis. MiR-138 may be a target for therapeutic intervention in TRAIL-based drug treatments of resistant hepatocellular carcinoma or could be a biomarker to select patients who may benefit from the treatment.

  5. Acute blood glucose fluctuation enhances rat aorta endothelial cell apoptosis, oxidative stress and pro-inflammatory cytokine expression in vivo.

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    Wu, Na; Shen, Haitao; Liu, Henan; Wang, Yanjun; Bai, Yu; Han, Ping

    2016-08-05

    Complications of diabetes mellitus (DM) are related not only to elevated plasma glucose, but also plasma glucose fluctuations. However, the specific mechanism underlying the role of plasma glucose fluctuation in the pathogenesis of DM complications remains poorly understood. In the present study, the influence of acute fluctuant hyperglycemia and persistent hyperglycemia on vascular endothelial cell apoptosis, function, oxidative stress and inflammation was examined in vivo. Rats were assigned to three different groups (n = 10/group) that received 48-h infusions of saline (SAL group), continuous 50 % glucose (constant high glucose group [CHG]), or intermittent 50 % glucose (acute blood glucose fluctuation group [AFG]). Plasma 8-isoprostaglandin, interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α) and intercellular adhesion molecule-1 (ICAM-1) levels were quantified by using enzyme-linked immunosorbent assay (ELISA) commercial kits. Plasma insulin levels were measured by radioimmunoassays (RIAs) using kits. The aortic segment was collected. The levels of malondialdehyde (MDA) and activity of glutathione peroxidase (GSH-PX) were measured in endothelial homogenates prepared from endothelial cells harvested from the aorta using colorimetric kits. Apoptosis of vascular endothelial cells was determined with terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL). Endothelial dysfunction was assessed by isometric tension recording to evaluate the endothelial function. The expression of B cell lymphoma-2 (Bcl-2), Bcl-2 Associated X protein (Bax), pro caspase-3, caspase-3 p17, 3-nitrotyrosine (3-NT) and p47phox protein in rat aortic endothelial cells were tested with Western blot analysis. Endothelial cells reactive oxygen species (ROS) formation was determined using dihydroethidium-dependent fluorescence microtopography in aortic cryo-sections. Expression of IL-6, TNF-α and ICAM-1 mRNAs in vascular endothelial cells were determined by real

  6. Isorhamnetin flavonoid synergistically enhances the anticancer activity and apoptosis induction by cis-platin and carboplatin in non-small cell lung carcinoma (NSCLC)

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    Zhang, Bao-Yi; Wang, Yan-Ming; Gong, Hai; Zhao, Hui; Lv, Xiao-Yan; Yuan, Guang-Hui; Han, Shao-Rong

    2015-01-01

    The development of novel antitumor drugs for the treatment of non-small cell lung carcinoma NSCLC is imperative in order to improve the efficacy of lung cancer therapy and prognosis. In the current study, we demonstrated the antitumor activity of isorhamnetin and its combinations with cisplatin and carboplatin against A-549 lung cancer cells. In order to assess the anticancer enhancing effect of isorhamnetin on cisplatin and carboplatin, A-549 cells were treated with isorhamnetin, cisplatin, carboplatin and their combinations and cell viability, cell apoptosis, cell cycle arrest as well as loss of mitochondrial membrane potential were evaluated by MTT assay, flow cytometry, confocal microscopy and fluorescence microscopy. The effect of the drugs on cancer cell migration, microtubule depolymerization as well activation of caspases was also studied. The results revealed that, as compared to single drug treatment, the combination of isorhamnetin with cisplatin and carboplatin resulted in greater effect in inhibiting cancer cell growth and inducing apoptosis. Combination of isorhamnetin with cisplatin and carboplatin resulted in more potent apoptosis induction as revealed by fluorescence microscopy using AO/PI double staining. Isorhamnetin and its combinations also triggered microtubule distortion and depolymerization. The combination of isorhamnetin with cisplatin and carboplatin increased the number of cells in G2/M phase dramatically as compared to single drug treatment. Moreover, isorhamnetin and its combinations with known anticancer drugs induced disruption of the mitochondrial membrane potential as well as activation of caspases 3, 9 and poly-(ADP-ribose) polymerase in A-549 cells. Isorhamnetin as well as its combinations with cisplatin and carboplatin resulted in inhibition of cancer cell migration significantly. Results of the current study suggest that isorhamnetin combinations with cisplatin and carboplatin might be a potential clinical chemotherapeutic

  7. Pokemon enhances proliferation, cell cycle progression and anti-apoptosis activity of colorectal cancer independently of p14ARF-MDM2-p53 pathway.

    Science.gov (United States)

    Zhao, Yi; Yao, Yun-hong; Li, Li; An, Wei-fang; Chen, Hong-zen; Sun, Li-ping; Kang, Hai-xian; Wang, Sen; Hu, Xin-rong

    2014-12-01

    Pokemon has been showed to directly suppress p14(ARF) expression and also to overexpress in multiple cancers. However, p14(ARF)-MDM2-p53 pathway is usually aberrant in colorectal cancer (CRC). The aim is to confirm whether Pokemon plays a role in CRC and explore whether Pokemon works through p14(ARF)-MDM2-p53 pathway in CRC. Immunohistochemistry for Pokemon, p14(ARF) and Mtp53 protein was applied to 45 colorectal epitheliums (CREs), 42 colorectal adenomas (CRAs) and 66 CRCs. Pokemon was knocked down with RNAi technique in CRC cell line Lovo to detect mRNA expression of p14(ARF) with qRT-PCR, cell proliferation with CCK8 assay, and cell cycle and apoptosis with flowcytometry analysis. The protein expression rates were significantly higher in CRC (75.8%) than in CRE (22.2 %) or CRA (38.1%) for Pokemon and higher in CRC (53.0%) than in CRE (0) or CRA (4.8%) for Mtp53, but not significantly different in CRC (86.4 %) versus CRE (93.3%) or CRA (90.5 %) for p14(ARF). Higher expression rate of Pokemon was associated with lymph node metastasis and higher Duke's stage. After knockdown of Pokemon in Lovo cells, the mRNA level of p14(ARF) was not significantly changed, the cell proliferation ability was decreased by 20.6%, cell cycle was arrested by 55.7% in G0/G1 phase, and apoptosis rate was increased by 19.0%. Pokemon enhanced the oncogenesis of CRC by promoting proliferation, cell cycle progression and anti-apoptosis activity of CRC cells independently of p14(ARF)-MDM2-p53 pathway. This finding provided a novel idea for understanding and further studying the molecular mechanism of Pokemon on carcinogenesis of CRC.

  8. Treadmill exercise ameliorates symptoms of methimazole-induced hypothyroidism through enhancing neurogenesis and suppressing apoptosis in the hippocampus of rat pups.

    Science.gov (United States)

    Shin, Mal-Soon; Ko, Il-Gyu; Kim, Sung-Eun; Kim, Bo-Kyun; Kim, Tae-Soo; Lee, Shin-Ho; Hwang, Dong-Sup; Kim, Chang-Ju; Park, Jin-Kook; Lim, Baek-Vin

    2013-05-01

    Thyroid hormones play a crucial role in new neuron production and maturation during brain development. Physical exercise is known to promote cell survival and functional recovery after brain injuries. In the present study, we investigated the effects of treadmill exercise on short-term memory, spatial learning ability, neurogenesis, and apoptosis in hypothyroidism rat pups. On the 14th perinatal day, the pregnant rats were divided into two groups: the maternal control group and the maternal methimazole (MMI)-treated group. For the induction of hypothyroidism in rat pups, MMI was added to the drinking water (0.02%, wt/vol), from the 14th prenatal day to the 49th postnatal day. After delivery, the male rat pups born from the maternal control group were assigned into the control group and the control and exercise group. The rat pups born from the maternal MMI-treated group were divided into the hypothyroidism-induction group and the hypothyroidism-induction and treadmill exercise group. The rat pups in the exercise groups were forced to run on a motorized treadmill for 30min once a day, starting on the 22nd postnatal day for 4 weeks. Induction of hypothyroidism during the fetal and early postnatal period showed suppression of neurogenesis and enhancement of apoptosis in the hippocampus. Short-term memory and spatial learning ability were deteriorated in the hypothyroidism rat pups. Treadmill exercise during the postnatal period increased neurogenesis and inhibited apoptosis, and resulted in the improvement of short-term memory and spatial learning ability in the hypothyroidism rat pups. Copyright © 2013 ISDN. Published by Elsevier Ltd. All rights reserved.

  9. Combining trail with PI3 kinase or HSP90 inhibitors enhances apoptosis in colorectal cancer cells via suppression of survival signaling.

    Science.gov (United States)

    Saturno, Grazia; Valenti, Melanie; De Haven Brandon, Alexis; Thomas, George V; Eccles, Suzanne; Clarke, Paul A; Workman, Paul

    2013-08-01

    TRAIL has been shown to induce apoptosis in cancer cells, but in some cases they fail to respond to this ligand. We explored the ability of representative phosphatidylinositol-3-kinase (PI3 Kinase)/mTOR and HSP90 inhibitors to overcome TRAIL resistance by increasing apoptosis in colorectal cancer models. We determined the sensitivity of 27 human colorectal cancer and 2 non-transformed colon epithelial cell lines to TRAIL treatment. A subset of the cancer cell lines with a range of responses to TRAIL was selected from the panel for treatment with TRAIL combined with the PI3 Kinase/mTOR inhibitor PI-103 or the HSP90 inhibitor 17-AAG (tanespimycin). Two TRAIL-resistant cell lines were selected for in vivo combination studies with TRAIL and 17-AAG. We found that 13 colorectal cancer cell lines and the 2 non-transformed colon epithelial cell lines were resistant to TRAIL. We demonstrated that co-treatment of TRAIL and PI-103 or 17-AAG was synergistic or additive and significantly enhanced apoptosis in colorectal cancer cells. This was associated with decreased expression or activity of survival protein biomarkers such as ERBB2, AKT, IKKα and XIAP. In contrast, the effect of the combination treatments in non-transformed colon cells was minimal. We show here for the first time that co-treatment in vivo with TRAIL and 17-AAG in two TRAIL-resistant human colorectal cancer xenograft models resulted in significantly greater tumor growth inhibition compared to single treatments. We propose that combining TRAIL with PI3 Kinase/mTOR or HSP90 inhibitors has therapeutic potential in the treatment of TRAIL-resistant colorectal cancers.

  10. Interleukin 10 enhanced CD8+ T cell activity and reduced CD8+T cell apoptosis in patients with diffuse large B cell lymphoma.

    Science.gov (United States)

    Qiu, Huiying; Hu, Xiaoxia; Gao, Lei; Chen, Li; Chen, Jie; Yuan, Joanna; Huang, Chongmei; Xu, Xiaoqian; Yang, Jianmin

    2017-11-15

    The pleiotropic cytokine interleukin (IL)-10 is best characterized by its ability to downregulate inflammation and promote peripheral tolerance. On the other hand, IL-10 was also found to maintain the effector response of CD8 + T cells and promote the expansion of tumor-resident CD8 + T cells. In diffuse large B cell lymphoma (DLBCL), the role of IL-10 has been characterized in tumor cells but not in CD8 + T cells. We found that CD8 + T cells in DLBCL presented robust interferon (IFN)-γ expression early during TCR-activation but could not maintain this response later on, which was characterized by significantly lower CD8 + T cell degranulation and higher apoptosis. These observations were associated with higher PD-1 expression in DLBCL CD8 + T cells. Furthermore, the PD-1 + cells were strongly enriched in the IFN-γ + , but not the IFN-γ - , fraction. Interestingly, exogenous IL-10 significantly improved the survival of DLBCL CD8 + T cells, and resulted in significantly higher IFN-γ, ganzyme A and granzyme B expression in the absence of CD19 + tumor cells, and significantly improved CD8 + T cell-mediated specific lysis of CD19 + tumor cells. IL-10 did not alter the expression of PD-1 in DLBCL CD8 + T cells, but curiously, IL-10-treated DLBCL CD8 + T cells were less susceptible to PD-L1-mediated apoptosis. We then demonstrated that IL-10 treatment significantly elevated the expression of pro-survival factor Bcl-2. Blocking IL-10 resulted in higher apoptosis, fewer IFN-γ + CD8 + T cells, and lower Bcl-2 expression. IL-10 also significantly increased STAT3, but not STAT1, phosphorylation in CD8 + T cells. Together, these results suggested that IL-10 could enhance CD8 + T cell inflammation in DLBCL patients. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Cox-2 Inhibition Protects against Hypoxia/Reoxygenation-Induced Cardiomyocyte Apoptosis via Akt-Dependent Enhancement of iNOS Expression

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    Lei Pang

    2016-01-01

    Full Text Available The present study explored the potential causal link between ischemia-driven cyclooxygenase-2 (COX-2 expression and enhanced apoptosis during myocardial ischemia/reperfusion (I/R by using H9C2 cardiomyocytes and primary rat cardiomyocytes subjected to hypoxia/reoxygenation (H/R. The results showed that H/R resulted in higher COX-2 expression than that of controls, which was prevented by pretreatment with Helenalin (NFκB specific inhibitor. Furthermore, pretreatment with NS398 (COX-2 specific inhibitor significantly attenuated H/R-induced cell injury [lower lactate dehydrogenase (LDH leakage and enhanced cell viability] and apoptosis (higher Bcl2 expression and lower level of cleaved caspases-3 and TUNEL-positive cells in cardiomyocytes. The amelioration of posthypoxic apoptotic cell death was paralleled by significant attenuation of H/R-induced increases in proinflammatory cytokines [interleukin 6 (IL6 and tumor necrosis factor (TNFα] and reactive oxygen species (ROS production and by higher protein expression of phosphorylated Akt and inducible nitric oxide synthase (iNOS and enhanced nitric oxide production. Moreover, the application of LY294002 (Akt-specific inhibitor or 1400W (iNOS-selective inhibitor cancelled the cellular protective effects of NS398. Findings from the current study suggest that activation of NFκB during cardiomyocyte H/R induces the expression of COX-2 and that higher COX-2 expression during H/R exacerbates cardiomyocyte H/R injury via mechanisms that involve cross talks among inflammation, ROS, and Akt/iNOS/NO signaling.

  12. Combination Treatment with Sublethal Ionizing Radiation and the Proteasome Inhibitor, Bortezomib, Enhances Death-Receptor Mediated Apoptosis and Anti-Tumor Immune Attack

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    Ercan Cacan

    2015-12-01

    Full Text Available Sub-lethal doses of radiation can modulate gene expression, making tumor cells more susceptible to T-cell-mediated immune attack. Proteasome inhibitors demonstrate broad anti-tumor activity in clinical and pre-clinical cancer models. Here, we use a combination treatment of proteasome inhibition and irradiation to further induce immunomodulation of tumor cells that could enhance tumor-specific immune responses. We investigate the effects of the 26S proteasome inhibitor, bortezomib, alone or in combination with radiotherapy, on the expression of immunogenic genes in normal colon and colorectal cancer cell lines. We examined cells for changes in the expression of several death receptors (DR4, DR5 and Fas commonly used by T cells for killing of target cells. Our results indicate that the combination treatment resulted in increased cell surface expression of death receptors by increasing their transcript levels. The combination treatment further increases the sensitivity of carcinoma cells to apoptosis through FAS and TRAIL receptors but does not change the sensitivity of normal non-malignant epithelial cells. Furthermore, the combination treatment significantly enhances tumor cell killing by tumor specific CD8+ T cells. This study suggests that combining radiotherapy and proteasome inhibition may simultaneously enhance tumor immunogenicity and the induction of antitumor immunity by enhancing tumor-specific T-cell activity.

  13. Downregulation of Enhancer of Zeste Homolog 2 (EZH2) is essential for the Induction of Autophagy and Apoptosis in Colorectal Cancer Cells.

    Science.gov (United States)

    Yao, Yizhou; Hu, Hao; Yang, Yong; Zhou, Guoqiang; Shang, Zengfu; Yang, Xiaodong; Sun, Kang; Zhan, Shenghua; Yu, Zhengyuan; Li, Peiyao; Pan, Guofeng; Sun, Liang; Zhu, Xinguo; He, Songbing

    2016-10-03

    Increasing evidence indicates that elevated expression of enhancer of zeste homolog 2 gene (EZH2) in many human malignant tumors acts a significant role in the oncogenic process. However, the underlying molecular mechanism is still unclarified. It is evident that apoptosis and autophagy of tumor cells is crucial for the tumorigenesis and progression of cancer, however, the exact role of EZH2 plays in apoptosis and autophagy has not been fully elucidated in colorectal cancer (CRC). Our previous study found that the expression level of EZH2 was higher in CRC tumor tissues than in the paired normal tissues using immunohistochemical analysis. We also recently found that the autophagy-related gene-related protein Ambra1 plays an important role in the autophagy pathway in CRC cells. In this study, mRNA and protein expression of EZH2 in four CRC cell lines were tested at first and RKO and HCT116 cells showed the highest levels among them. Here we transfected with EZH2-shRNA, or added DZNep (an EZH2 inhibitor) to RKO and HCT116 cells in order to detect the effect of EZH2 on autophagy via determining the change of the protein expression of LC3 and Ambra1. The outcome indicated an obvious decrease of autophagy level in cells transfected with EZH2-shRNA or DZNep. We also found the apoptotic rate of cells was elevated significantly after downregulation of EZH2. In addition, compared to control group, CRC cells transfected with EZH2-shRNA or added DZNep revealed a significantly increased G1 cell cycle rate and an obvious decrease in the G2 cell cycle rate. Further analysis showed that knockdown of EZH2 induced cell-cycle arrest in CRC cells. Meanwhile, downregulation of EZH2 in CRC cells induces autophagy and apoptosis. Taken together, our results suggest that EZH2 plays a critical role in autophagy and apoptosis in the progression of CRC, which potentially facilitates the development of an ideal strategy for combating colorectal cancer.

  14. M011L-deficient oncolytic myxoma virus induces apoptosis in brain tumor-initiating cells and enhances survival in a novel immunocompetent mouse model of glioblastoma.

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    Pisklakova, Alexandra; McKenzie, Brienne; Zemp, Franz; Lun, Xueqing; Kenchappa, Rajappa S; Etame, Arnold B; Rahman, Masmudur M; Reilly, Karlyne; Pilon-Thomas, Shari; McFadden, Grant; Kurz, Ebba; Forsyth, Peter A

    2016-03-08

    Myxoma virus (MYXV) is a promising oncolytic agent and is highly effective against immortalized glioma cells but less effective against brain tumor initiating cells (BTICs), which are believed to mediate glioma development/recurrence. MYXV encodes various proteins to attenuate host cell apoptosis, including an antiapoptotic Bcl-2 homologue known as M011L. Such proteins may limit the ability of MYXV to kill BTICs, which have heightened resistance to apoptosis. We hypothesized that infecting BTICs with an M011L-deficient MYXV construct would overcome BTIC resistance to MYXV. We used patient-derived BTICs to evaluate the efficacy of M011L knockout virus (vMyx-M011L-KO) versus wild-type MYXV (vMyx-WT) and characterized the mechanism of virus-induced cell death in vitro. To extend our findings in a novel immunocompetent animal model, we derived, cultured, and characterized a C57Bl/6J murine BTIC (mBTIC0309) from a spontaneous murine glioma and evaluated vMyx-M011L-KO efficacy with and without temozolomide (TMZ) in mBTIC0309-bearing mice. We demonstrated that vMyx-M011L-KO induces apoptosis in BTICs, dramatically increasing sensitivity to the virus. vMyx-WT failed to induce apoptosis as M011L protein prevented Bax activation and cytochrome c release. In vivo, intracranial implantation of mBTIC0309 generated tumors that closely recapitulated the pathological and molecular profile of human gliomas. Treatment of tumor-bearing mice with vMyx-M011L-KO significantly prolonged survival in immunocompetent-but not immunodeficient-mouse models, an effect that is significantly enhanced in combination with TMZ. Our data suggest that vMyx-M011L-KO is an effective, well-tolerated, proapoptotic oncolytic virus and a strong candidate for clinical translation. © The Author(s) 2016. Published by Oxford University Press on behalf of the Society for Neuro-Oncology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  15. PTH1–34 Blocks Radiation-induced Osteoblast Apoptosis by Enhancing DNA Repair through Canonical Wnt Pathway*

    Science.gov (United States)

    Chandra, Abhishek; Lin, Tiao; Zhu, Ji; Tong, Wei; Huo, Yanying; Jia, Haoruo; Zhang, Yejia; Liu, X. Sherry; Cengel, Keith; Xia, Bing; Qin, Ling

    2015-01-01

    Focal radiotherapy for cancer patients has detrimental effects on bones within the radiation field and the primary clinical signs of bone damage include the loss of functional osteoblasts. We reported previously that daily injection of parathyroid hormone (PTH, 1–34) alleviates radiation-induced osteopenia in a preclinical radiotherapy model by improving osteoblast survival. To elucidate the molecular mechanisms, we irradiated osteoblastic UMR 106-01 cells and calvarial organ culture and demonstrated an anti-apoptosis effect of PTH1–34 on these cultures. Inhibitor assay indicated that PTH exerts its radioprotective action mainly through protein kinase A/β-catenin pathway. γ-H2AX foci staining and comet assay revealed that PTH efficiently promotes the repair of DNA double strand breaks (DSBs) in irradiated osteoblasts via activating the β-catenin pathway. Interestingly, Wnt3a alone also blocked cell death and accelerated DNA repair in primary osteoprogenitors, osteoblastic and osteocytic cells after radiation through the canonical signaling. Further investigations revealed that both Wnt3a and PTH increase the amount of Ku70, a core protein for initiating the assembly of DSB repair machinery, in osteoblasts after radiation. Moreover, down-regulation of Ku70 by siRNA abrogated the prosurvival effect of PTH and Wnt3a on irradiated osteoblasts. In summary, our results identify a novel role of PTH and canonical Wnt signaling in regulating DSB repair machinery and apoptosis in osteoblasts and shed light on using PTH1–34 or Wnt agonist as possible therapy for radiation-induced osteoporosis. PMID:25336648

  16. MicroRNA-203 Is a Prognostic Indicator in Bladder Cancer and Enhances Chemosensitivity to Cisplatin via Apoptosis by Targeting Bcl-w and Survivin.

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    Xin Zhang

    Full Text Available Resistance to cisplatin-based chemotherapy is a major cause of treatment failure in advanced bladder cancer (BC patients. There is increasing evidence that microRNAs are involved in the development and progression of BC. However, little is known about the function of microRNAs in predicting the effect of adjuvant chemotherapy on BC survival and regulating response to cisplatin. To address this issue, we employed RT-qPCR to evaluate the clinical significance of miR-203 expression in 108 tissues of BC patients receiving cisplatin-based adjuvant chemotherapy, and performed in vitro studies to explore chemotherapeutic sensitivity to cisplatin in miR-203 overexpressing BC cells. We found miR-203 levels were significantly lower in BC progression group than non-progression group (P<0.001. ROC curve analysis illustrated miR-203 could significantly distinguish progressed patients from those without progression (P<0.001, yielding an area under the ROC curve of 0.839 (95% CI, 0.756-0.903. Moreover, low miR-203 expression correlated with shortened progression free survival (PFS and overall survival (OS of BC patients, and was an independent prognostic factor. Overexpression of miR-203 in 5637 and T24 BC cells could decrease cell viability, enhance cisplatin cytotoxicity, and promote apoptosis. Western blotting and luciferase reporter assay showed Bcl-w and Survivin were direct downstream targets of miR-203. There was also a significant inverse association between miR-203 and Bcl-w or Survivin expression in BC tissues (r = -0.781, -0.740, both P<0.001. In conclusion, decreased miR-203 predicts progression and poor prognosis for BC patients treated with cisplatin-based chemotherapy while miR-203 overexpression can enhance cisplatin sensitization by promoting apoptosis via directly targeting Bcl-w and Survivin.

  17. Enhancement of Cisplatin-Mediated Apoptosis in Ovarian Cancer Cells through Potentiating G2/M Arrest and p21 Upregulation by Combinatorial Epigallocatechin Gallate and Sulforaphane

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    Huaping Chen

    2013-01-01

    Full Text Available Advanced-stage ovarian cancer is characterized by high mortality due to development of resistance to conventional chemotherapy. Novel compounds that can enhance the efficacy of conventional chemotherapy in ovarian cancer may overcome this drug resistance. Consumption of green tea (epigallocatechin gallate, EGCG and cruciferous vegetables (sulforaphane, SFN is inversely associated with occurrence of ovarian cancer and has anticancer effects through targeting multiple molecules in cancer cells. However, the effects of EGCG and SFN combinational treatment on ovarian cancer cells and on efficacy of cisplatin to these cells are unknown. In this study, EGCG or SFN was used to treat both cisplatin-sensitive (A2780 and cisplatin-resistant (A2780/CP20 ovarian cancer cells alone or in combination with cisplatin. We found that EGCG and SFN combinational treatment can reduce cell viability of both ovarian cancer cell lines time- and dose-dependently. Furthermore, EGCG and SFN combinational treatment can enhance cisplatin-induced apoptosis and G2/M phase arrest, thereby enhancing the efficacy of cisplatin on both cisplatin-sensitive and cisplatin-resistant ovarian cancer cells. EGCG and SFN combinational treatment upregulated p21 expression induced by cisplatin in cisplatin-sensitive ovarian cancer cells, while p27 expression was not regulated by these treatments. Collectively, these studies provide novel approaches to overcoming cisplatin chemotherapy resistance in ovarian cancer.

  18. Combination of graphene oxide-silver nanoparticle nanocomposites and cisplatin enhances apoptosis and autophagy in human cervical cancer cells.

    Science.gov (United States)

    Yuan, Yu-Guo; Gurunathan, Sangiliyandi

    2017-01-01

    Cisplatin (Cis) is a widely used chemotherapeutic drug for treating a variety of cancers, due to its ability to induce cell death in cancer cells significantly. Recently, graphene and its modified nanocomposites have gained much interest in cancer therapy, due to their unique physicochemical properties. The objective of this study was to investigate the combination effect of Cis and a reduced graphene oxide-silver nanoparticle nanocomposite (rGO-AgNPs) in human cervical cancer (HeLa) cells. We synthesized AgNPs, rGO, and rGO-AgNP nanocomposites using C-phycocyanin. The synthesized nanomaterials were characterized using various analytical techniques. The anticancer properties of the Cis, rGO-AgNPs, and combination of Cis and rGO-AgNPs were evaluated using a series of cellular assays, such as cell viability, cell proliferation, LDH leakage, reactive oxygen species generation, and cellular levels of oxidative and antioxidative stress markers such as malondialdehyde, glutathione, SOD, and CAT. The expression of proapoptotic, antiapoptotic, and autophagy genes were measured using real-time reverse-transcription polymerase chain reaction. The synthesized AgNPs were well dispersed, homogeneous, and spherical, with an average size of 10 nm and uniformly distributed on graphene sheets. Cis, GO, rGO, AgNPs, and rGO-AgNPs inhibited cell viability in a dose-dependent manner. The combination of Cis and rGO-AgNPs showed significant effects on cell proliferation, cytotoxicity, and apoptosis. The combination of Cis and rGO-AgNPs had more pronounced effects on the expression of apoptotic and autophagy genes, and also significantly induced the accumulation of autophagosomes and autophagolysosomes, which was associated with the generation of reactive oxygen species. Our findings substantiated rGO-AgNPs strongly potentiating Cis-induced cytotoxicity, apoptosis, and autophagy in HeLa cells, and hence rGO-AgNPs could be potentially applied to cervical cancer treatment as a powerful

  19. Necdin enhances myoblasts survival by facilitating the degradation of the mediator of apoptosis CCAR1/CARP1.

    Directory of Open Access Journals (Sweden)

    Stephanie François

    Full Text Available Regeneration of muscle fibers, lost during pathological muscle degeneration or after injuries, is sustained by the production of new myofibers by means of the satellite cells. Survival of the satellite cells is a critical requirement for efficient muscle reconstitution. Necdin, a member of the MAGE proteins family, is expressed in satellite cell-derived myogenic precursors during perinatal growth and in the adult upon activation during muscle regeneration, where it plays an important role both in myoblast differentiation and survival. We show here that necdin exerts its pro-survival activity by counteracting the action of the pro-apoptotic protein Cell Cycle Apoptosis Regulatory Protein (CCAR1/CARP1 that we have identified as a new molecular interactor of necdin by two-hybrid screening. Necdin is responsible for the maintenance of CCAR1 protein levels, by implementing its ubiquitination and degradation through the proteasome. Taken together, these data shed new light on the molecular mechanism of necdin anti-apoptotic activity in myogenesis.

  20. Enhancement of amygdalin activated with β-D-glucosidase on HepG2 cells proliferation and apoptosis.

    Science.gov (United States)

    Zhou, Cunshan; Qian, Lichun; Ma, Haile; Yu, Xiaojie; Zhang, Youzuo; Qu, Wenjuan; Zhang, Xiaoxu; Xia, Wei

    2012-09-01

    The growth inhibition and induction of apoptosis brought by amygdalin and activated with β-D-glucosidase were tested for cytoactivity in HepG2 cells. The MTT viability assay showed that all samples had effects on HepG2 proliferation in dose and time response manners. IC50 of stand-alone amygdalin and activation with β-D-glucosidase on the proliferation of HepG2 cells for 48 h were 458.10 mg/mL and 3.2 mg/mL, respectively. Moreover, apoptotic cells were determined by AO/EB (acridine orange/ethidium bromide) fluorescent staining method and Annexin V-FITC/PI staining flow cytometry cell cycle analysis. With increasing of amygdalin concentration and the incubation time, the apoptotic rate was heightened. Compared with the control, there was significant difference (pamygdalin had no strong anti-HepG2 activity; however the ingredients of amygdalin activated with β-D-glucosidase had a higher and efficient anti-HepG2 activity. It was therefore suggested that this combination strategy may be applicable for treating tumors with a higher activity. Copyright © 2012 Elsevier Ltd. All rights reserved.

  1. Enhanced cytotoxicity and apoptosis by raloxifene in combination with estrogen and methotrexate in human endometrial stromal cells.

    Science.gov (United States)

    Nikolic, Ivana; Andjelkovic, Marija; Zaric, Milan; Zelen, Ivanka; Milosavljevic, Zoran; Canovic, Petar; Mitrovic, Marina

    2017-11-22

    Endometrial hyperplasia is a condition that may lead to the development of endometrial carcinoma. Initially, changes of the endometrium are caused by the estrogen's hyperstimulation that may lead to the development of an irregular bleeding and the infertility problems. Therapy of endometrial hyperplasia is limited to medical and surgical approaches. During the past decade, the new types of drugs were developed for the treatment of the endometrial hyperplasia. Here, for the first time, we investigated the cytotoxic effects of the various combinations of estrogen, raloxifene, and methotrexate in human ThESC cell line as a possible potential treatment of the endometrial hyperplasia. Our aim was to investigate and to determine the most efficient combination of investigated drugs in ThESC cells during 24-hr period using MTT assay, FACS analysis, and immunofluorescence staining. Our results demonstrated that the combination of raloxifene with methotrexate efficiently induced both the cytotoxicity and apoptosis in ThESC cells when compared to their single effect, as well as to the effect of combined treatment of raloxifene with estrogen. The application of the low doses of methotrexate combined with raloxifene offers all advantages of a potential beneficial antitumor match in cancer chemoprevention and therapy. © 2017 John Wiley & Sons A/S.

  2. The enhanced expression of death receptor 5 (DR5) mediated by HBV X protein through NF-kappaB pathway is associated with cell apoptosis induced by (TNF-α related apoptosis inducing ligand) TRAIL in hepatoma cells.

    Science.gov (United States)

    Kong, Fanyun; You, Hongjuan; Zhao, Jinjin; Liu, Wen; Hu, Lei; Luo, Wenya; Hu, Wei; Tang, Renxian; Zheng, Kuiyang

    2015-11-17

    HBV X protein (HBX) is associated with cell apoptosis mediated by TNF-α related apoptosis inducing ligand (TRAIL), while the role of HBX on the expressions of TRAIL receptors death receptor 4 (DR4) and DR5 are unclear. In this study, we detected the cell apoptosis induced by TRAIL as well as gene and protein expressions of DR4 and DR5 in Huh-7 cells steadily transfected with HBX (Huh-7-HBX cells). In addition, we investigated the activation of different pathways associated with the expressions of TRAIL receptors in Huh-7-HBX cells. The apoptosis of Huh-7-HBX cells induced by TRAIL was evaluated by flow cytometry analysis. The levels of DR4 and DR5 expression in cells were determined by real-time PCR and western blotting analysis. The activities of JNK pathway and NF-kappaB (NF-κB) pathway were demonstrated by western blotting assay. Compared to control cells, the percentage of cell apoptosis was increased in Huh-7-HBX cells. The increased expressions of DR4 and DR5 on gene and protein levels were observed in Huh-7-HBX cells. Further researches suggested that activation of JNK pathway was increased but not involved in the expression of TRAIL receptors in HBX positive cells. The activation of NF-κB pathway increased and was responsible for DR5 expression and cell apoptosis in HBX positive cells. These results demonstrate that increased apoptosis induced by TRAIL is associated with increased expression of DR5 that mediated by HBX through NF-κB pathway. This finding provides a critical insight into the mechanism of hepatocyte apoptosis mediated by HBX in HBV infection.

  3. Exercise training enhanced SIRT1 longevity signaling replaces the IGF1 survival pathway to attenuate aging-induced rat heart apoptosis.

    Science.gov (United States)

    Lai, Chao-Hung; Ho, Tsung-Jung; Kuo, Wei-Wen; Day, Cecilia-Hsuan; Pai, Pei-Ying; Chung, Li-Chin; Liao, Po-Hsiang; Lin, Feng-Huei; Wu, En-Ting; Huang, Chih-Yang

    2014-01-01

    Cardiovascular disease is the second leading cause of death (9.1 %) in Taiwan. Heart function deteriorates with age at a rate of 1 % per year. As society ages, we must study the serious problem of cardiovascular disease. SIRT1 regulates important cellular processes, including anti-apoptosis, neuronal protection, cellular senescence, aging, and longevity. In our previous studies, rats with obesity, high blood pressure, and diabetes exhibiting slowed myocardial performance and induced cell apoptosis were reversed via sports training through IGF1 survival signaling compensation. This study designed a set of experiments with rats, in aging and exercise groups, to identify changes in myocardial cell signaling transduction pathways. Three groups of three different aged rats, 3, 12, and 18 months old, were randomly divided into aging groups (C3, A12, and A18) and exercise groups (E3, AE12, and AE18). The exercise training consisted of swimming five times a week with gradual increases from the first week from 20 to 60 min for 12 weeks. After the sports training process was completed, tissue sections were taken to observe cell organization (hematoxylin and eosin (H&E) stain) and apoptosis (terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assays) and to observe any changes in the myocardial tissues and proteins (Western blotting). The experimental results show that cardiomyocyte apoptotic pathway protein expression increased with age in the aging groups (C3, A12, and A18), with improvement in the exercise group (E3, AE12, and AE18). However, the expression of the pro-survival p-Akt protein decreased significantly with age and reduced performance. The IGF1R/PI3K/Akt survival pathway in the heart of young rats can indeed be increased through exercise training. As rats age, this pathway loses its original function, even with increasing upstream IGF1. However, levels of SIRT1 and its downstream target PGC-1α were found to increase with age and

  4. Silencing of Pokemon enhances caspase-dependent apoptosis via fas- and mitochondria-mediated pathways in hepatocellular carcinoma cells.

    Directory of Open Access Journals (Sweden)

    Yu-Qin Zhang

    Full Text Available The role of Pokemon (POK erythroid myeloid ontogenic actor, a recently identified POK transcription factor with proto-oncogenic activity, in hepatocellular carcinogenesis has only been assessed by a few studies. Our previous study revealed that Pokemon is overexpressed in hepatocellular carcinomas (HCC and promotes HCC cell proliferation and migration via an AKT- and ERK- dependent manner. In the present study, we used the TUNEL assay and FACS analysis to demonstrate that oxaliplatin induced apoptosis was significantly increased in cells with silenced Pokemon. Western blots showed that p53 expression and phosphorylation were significantly increased in Pokemon defective cells, thereby initiating the mitochondria-mediated and death receptor-mediated apoptotic pathways. In the mitochondria-mediated pathway, expression of pro-apoptotic Bcl-2 family members (including Bad, Bid, Bim and Puma as well as AIF was increased and decreasing the mitochondrial membrane potential resulted in cytochrome C released from mitochondrial in HepG2 si-Pokemon cells. In addition, upon oxaliplatin treatment of Pokemon-silenced cells, the FAS receptor, FADD and their downstream targets caspase-10 and caspase-8 were activated, causing increased release of caspase-8 active fragments p18 and p10. Increased activated caspase-8-mediated cleavage and activation of downstream effector caspases such as caspase-9 and caspase-3 was observed in HepG2 si-Pokemon cells as compared to control. Therefore, Pokemon might serve as an important mediator of crosstalk between intrinsic and extrinsic apoptotic pathways in HCC cells. Moreover, our findings suggest that Pokemon could be an attractive therapeutic target gene for human cancer therapy.

  5. Silencing of Pokemon enhances caspase-dependent apoptosis via fas- and mitochondria-mediated pathways in hepatocellular carcinoma cells.

    Science.gov (United States)

    Zhang, Yu-Qin; Xiao, Chuan-Xing; Lin, Bi-Yun; Shi, Ying; Liu, Yun-Peng; Liu, Jing-Jing; Guleng, Bayasi; Ren, Jian-Lin

    2013-01-01

    The role of Pokemon (POK erythroid myeloid ontogenic actor), a recently identified POK transcription factor with proto-oncogenic activity, in hepatocellular carcinogenesis has only been assessed by a few studies. Our previous study revealed that Pokemon is overexpressed in hepatocellular carcinomas (HCC) and promotes HCC cell proliferation and migration via an AKT- and ERK- dependent manner. In the present study, we used the TUNEL assay and FACS analysis to demonstrate that oxaliplatin induced apoptosis was significantly increased in cells with silenced Pokemon. Western blots showed that p53 expression and phosphorylation were significantly increased in Pokemon defective cells, thereby initiating the mitochondria-mediated and death receptor-mediated apoptotic pathways. In the mitochondria-mediated pathway, expression of pro-apoptotic Bcl-2 family members (including Bad, Bid, Bim and Puma) as well as AIF was increased and decreasing the mitochondrial membrane potential resulted in cytochrome C released from mitochondrial in HepG2 si-Pokemon cells. In addition, upon oxaliplatin treatment of Pokemon-silenced cells, the FAS receptor, FADD and their downstream targets caspase-10 and caspase-8 were activated, causing increased release of caspase-8 active fragments p18 and p10. Increased activated caspase-8-mediated cleavage and activation of downstream effector caspases such as caspase-9 and caspase-3 was observed in HepG2 si-Pokemon cells as compared to control. Therefore, Pokemon might serve as an important mediator of crosstalk between intrinsic and extrinsic apoptotic pathways in HCC cells. Moreover, our findings suggest that Pokemon could be an attractive therapeutic target gene for human cancer therapy.

  6. Downregulation of miR-210 expression inhibits proliferation, induces apoptosis and enhances radiosensitivity in hypoxic human hepatoma cells in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Wei, E-mail: detachedy@yahoo.com.cn [Department of Radiobiology, School of Radiological Medicine and Protection, Soochow University, Suzhou (China); Sun, Ting [Brain and Nerve Research Laboratory, The First Affiliated Hospital, Soochow University, Suzhou (China); Cao, Jianping; Liu, Fenju [Department of Radiobiology, School of Radiological Medicine and Protection, Soochow University, Suzhou (China); Tian, Ye [Department of Radiotherapy and Oncology, The Second Affiliated Hospital, Soochow University, Suzhou (China); Zhu, Wei [Department of Radiobiology, School of Radiological Medicine and Protection, Soochow University, Suzhou (China)

    2012-05-01

    Hypoxia is a common feature of solid tumors and an important contributor to tumor radioresistance. miR-210 is the most consistently and robustly induced microRNA under hypoxia in different types of tumor cells and normal cells. In the present study, to explore the feasibility of miR-210 as an effective therapeutic target, lentiviral-mediated anti-sense miR-210 gene transfer technique was employed to downregulate miR-210 expression in hypoxic human hepatoma SMMC-7721, HepG2 and HuH7 cells, and phenotypic changes of which were analyzed. Hypoxia led to an increased hypoxia inducible factor-1{alpha} (HIF-1{alpha}) and miR-210 expression and cell arrest in the G{sub 0}/G{sub 1} phase in all cell lines. miR-210 downregulation significantly suppressed cell viability, induced cell arrest in the G{sub 0}/G{sub 1} phase, increased apoptotic rate and enhanced radiosensitivity in hypoxic human hepatoma cells. Moreover, apoptosis-inducing factor, mitochondrion-associated, 3 (AIFM3) was identified as a direct target gene of miR-210. AIFM3 downregulation by siRNA attenuated radiation induced apoptosis in miR-210 downregulated hypoxic human hepatoma cells. Taken together, these data suggest that miR-210 might be a potential therapeutic target and specific inhibition of miR-210 expression in combination with radiotherapy might be expected to exert strong anti-tumor effect on hypoxic human hepatoma cells. -- Highlights: Black-Right-Pointing-Pointer miR-210 downregulation radiosensitized hypoxic hepatoma. Black-Right-Pointing-Pointer AIFM3 was identified as a direct target gene of miR-210. Black-Right-Pointing-Pointer miR-210 might be a therapeutic target to hypoxic hepatoma.

  7. Anti-Lung Cancer Activity through Enhancement of Immunomodulation and Induction of Cell Apoptosis of Total Triterpenes Extracted from Ganoderma luncidum (Leyss. ex Fr. Karst.

    Directory of Open Access Journals (Sweden)

    Wei Cao

    2013-08-01

    Full Text Available Ganoderma luncidum (Leyss. ex Fr. Karst. (GLK has been used traditionally for the prevention and treatment of cancers or tumors for a long time in Traditional Chinese Medicine. The triterpenes as main effective components of GLK have been found to be beneficial for the efficacy. The purpose of this study was to examine the anti-lung cancer activity of triterpenes of GLK in vitro and in vivo and to explore their anti-lung cancer effects and potential mechanisms. A549 cells and Lewis tumor-bearing mice were used to evaluate the inhibition effects of triterpenes on cell proliferation and tumor growth. The IC50 of triterpenes of GLK on A549 cells was 24.63 μg/mL. Triterpenes of GLK could significantly inhibit tumor growth in mice (30, 60 and 120 mg/kg. The immune organs indexes including spleen and thymus were increased remarkedly by the treatment with triterpenes. Moreover, they were able to stimulate the immune response by increasing the expressions of IL-6 and TNF-α. Flow cytometric analysis revealed that cell arrest caused by triterpenes treatment (7.5, 15 and 30 μg/mL was in the G2/M phase in A549 cells. Triterpenes induced apoptosis by decreasing the expression of the antiapoptotic protein Bcl-2 and pro-caspase 9 and increasing the levels of cleaved-caspase 9. Our findings suggested that the triterpenes of GLK have anti-lung cancer activity in vitro and in vivo via enhancement of immunomodulation and induction of cell apoptosis. The study provides insights into the mechanism of GLK in the prevention and treatment of lung cancer.

  8. Valeriana amurensis improves Amyloid-beta 1-42 induced cognitive deficit by enhancing cerebral cholinergic function and protecting the brain neurons from apoptosis in mice.

    Science.gov (United States)

    Wang, Qiuhong; Wang, Changfu; Shu, Zunpeng; Chan, Kelvin; Huang, Shuming; Li, Yan; Xiao, Yang; Wu, Lihua; Kuang, Haixue; Sun, Xiaobo

    2014-04-28

    Valeriana amurensis, a perennial medicinal herb, has been widely used as anxiolytic, antidepressant, antispasmodic, and sedative in traditional Chinese medicines (TCMs). Moreover, it has been used to treat dementia in Mongolia preparations. In our previous study, we reported that AD-effective fraction of Valeriana amurensis (AD-EFV) has protective effect on Aβ-induced toxicity in PC12 cells. Up to now, however, the therapeutic effect of Valeriana amurensis on Alzheimer disease (AD) has not been explored. This study was designed to determine whether the AD-EFV could improve the Amyloid-beta (Aβ)-induced cognitive deficit and to explore the mechanism of AD-EFV improves cognitive deficit in intact animals. The constituents of AD-EFV were isolated with silica gel, octadecyl silica gel (ODS) column chromatography (CC) and preparative HPLC. The structures of compounds were determined by detailed NMR and ESI-MS data analyses. AD mice model was established by injecting A(β1-42) (1 μL, 200 μmol) into the bilateral ventricle. Cognitive performance was evaluated by the Morris water maze (MWM) test. The level of cerebral acetylcholine (ACh), the activities of acetylcholinesterase (AChE) and choline acetyltransferase (ChAT) were investigated using Enzyme-linked immunoassay (ELISA) kits. Brain sections were processed and neuronal apoptosis in hippocampus were evaluated by Hematoxylin and Eosin (HE), Nissl, and Tunel stainings. The analyses of p-ERK/ERK and Bcl-2/Bax protein expression by western blot assay were used to explore the anti-neuronal apoptosis mechanism of AD-EFV. Seventeen compounds (15 lignans and two iridoids) were isolated from AD-EFV. A significant improvement in cognitive function was observed in administrated AD-EFV AD model mice. AD-EFV increased the ACh level by enhancing the ChAT activity but has no effect on AChE activity in the cerebral cortex and hippocampus in mice. Moreover, the histological injury in hippocampus CA1 induced by A(β1-42) was

  9. Enhanced cytotoxicity of optimized liposomal genistein via specific induction of apoptosis in breast, ovarian and prostate carcinomas.

    Science.gov (United States)

    Phan, Vu; Walters, Jarvis; Brownlow, Bill; Elbayoumi, Tamer

    2013-12-01

    Clinical use of genistein against cancer is limited by its extremely low aqueous solubility, poor bioavailability and pharmacokinetics. Based on structural analogy with steroidal compounds, liposomal vehicle compositions were designed and optimized for maximum incorporation of genistein's flavonoid structure. Model conventional and stealth liposomes of genistein (GenLip)--incorporating unsaturated phospholipids and cholesterol--have demonstrated enhanced drug solubilization (over 350-folds > aqueous drug solution), shelf-life stability, and extended release profile. Owing to effective cellular delivery, preservation of genistein's antioxidant activity was confirmed through marked neutralization of peroxides via GenLip, in both quantitative and microscopic fluorescent-probe oxidation assays. Furthermore, significant broad-spectrum anticancer efficacy of GenLip, in murine and human cancer cell lines (p liposomes shows optimal loading capacity and physico-chemical properties, which improved cellular delivery and specific pro-apototic effectiveness of incorporated drug, against various cancers.

  10. Target cell-restricted and -enhanced apoptosis induction by a scFv:sTRAIL fusion protein with specificity for the pancarcinoma-associated antigen EGP2

    NARCIS (Netherlands)

    Bremer, Edwin; Kuijlen, Jos; Samplonius, Douwe; Walczak, H; de Leij, Lou; Helfrich, Wijnand

    2004-01-01

    The apparent tumor selective apoptosis-inducing activity of recombinant soluble TNF-related apoptosis-inducing ligand (TRAIL) has aroused much interest for use in clinical application. However, to exploit fully its therapeutic potential, the characteristics of both the TRAIL receptor system and

  11. miR-101 Enhances Cisplatin-Induced DNA Damage Through Decreasing Nicotinamide Adenine Dinucleotide Phosphate Levels by Directly Repressing Tp53-Induced Glycolysis and Apoptosis Regulator Expression in Prostate Cancer Cells.

    Science.gov (United States)

    Huang, Shiqiao; Yang, Zhiguo; Ma, Yong; Yang, Yiyong; Wang, Shangren

    2017-04-01

    Tp53-induced glycolysis and apoptosis regulator (TIGAR) enhances the pentose phosphate pathway, thereby contributing directly to DNA repair due to generation of nicotinamide adenine dinucleotide phosphate (NADPH) and ribose-5-phosphate, two key precursors of DNA synthesis and repair. Targetscan database showed that miR-101 was predicted to potentially target TIGAR. Therefore, we speculated that miR-101 could enhance cisplatin-induced DNA damage by directly repressing TIGAR expression in prostate cancer cells. We found that upregulation of miR-101 inhibited viability, induced apoptosis, increased glycolysis rate and fructose-2,6-bisphosphate levels, decreased glucose-6-phosphate dehydrogenase expression and NADPH levels, and enhanced cisplatin-induced DNA damage in prostate cancer cells. We also demonstrated that TIGAR was a direct target of miR-101 by using luciferase activity assay. Furthermore, this study revealed that the roles of knockdown of TIGAR were similar to miR-101 upregulation in prostate cancer cells. Taken together, miR-101 inhibited viability, induced apoptosis, reprogramed glucose metabolism, and enhanced cisplatin-induced DNA damage through decreasing NADPH levels by directly suppressing the expression of TIGAR in prostate cancer cells.

  12. t10c12 conjugated linoleic acid suppresses HER2 protein and enhances apoptosis in SKBr3 breast cancer cells: possible role of COX2.

    Directory of Open Access Journals (Sweden)

    Margaret Flowers

    Full Text Available BACKGROUND: HER2-targeted therapy with the monoclonal antibody trastuzumab (Herceptin has improved disease-free survival for women diagnosed with HER2-positive breast cancers; however, treatment resistance and disease progression are not uncommon. Current data suggest that resistance to treatment in HER2 cancers may be a consequence of NF-kappaB overexpression and increased COX2-derived prostaglandin E2 (PGE(2. Conjugated linoleic acid (CLA has been shown to have anti-tumor properties and to inhibit NF-kappaB activity and COX2. METHODS: In this study, HER2-overexpressing SKBr3 breast cancer cells were treated with t10c12 CLA. Protein expression of the HER2 receptor, nuclear NF-kappaB p65, and total and phosphorylated IkappaB were examined by western blot and immunofluorescence. PGE(2 levels were determined by ELISA. Proliferation was measured by metabolism of 3-(4, 5-Dimethylthiazol-2-yl-2, 5-diphenyltetrazolium bromide (MTT, and apoptosis was measured by FITC-conjugated Annexin V staining and flow cytometry. RESULTS/CONCLUSIONS: We observed a significant decrease in HER2 protein expression on western blot following treatment with 40 and 80 microM t10c12 CLA (p<0.01 and 0.001, respectively and loss of HER2 protein in cells using immunoflourescence that was most pronounced at 80 microM. Protein levels of nuclear NF-kappaB p65 were also significantly reduced at the 80 microM dose. This was accompanied by a significant decrease in PGE(2 levels (p = 0.05. Pretreatment with t10c12 CLA significantly enhanced TNFalpha-induced apoptosis and the anti-proliferative action of trastuzumab (p = 0.05 and 0.001, respectively. These data add to previous reports of an anti-tumor effect of t10c12 CLA and suggest an effect on the HER2 oncogene that may be through CLA mediated downregulation of COX2-derived PGE(2.

  13. Ulva lactuca polysaccharides prevent Wistar rat breast carcinogenesis through the augmentation of apoptosis, enhancement of antioxidant defense system, and suppression of inflammation

    Directory of Open Access Journals (Sweden)

    Abd-Ellatef GF

    2017-02-01

    cytokines tumor necrosis factor-α and nitric oxide were significantly ameliorated in DMBA-administered rats treated with ulvan polysaccharides as compared to DMBA-administered control. Conclusion: In conclusion, ulvan polysaccharides at the level of initiation and promotion might have potential chemopreventive effects against breast carcinogenesis. These preventive effects may be mediated through the augmentation of apoptosis, suppression of oxidative stress and inflammation, and enhancement of antioxidant defense system. Keywords: breast carcinogenesis, cancer initiation, cancer promotion, Ulva lactuca polysaccharides, DMBA, oxidative stress, apoptosis

  14. The antihypertension drug doxazosin suppresses JAK/STATs phosphorylation and enhances the effects of IFN-α/γ-induced apoptosis.

    Science.gov (United States)

    Park, Mi Sun; Kim, Boh-Ram; Kang, Sokbom; Kim, Dae-Yong; Rho, Seung Bae

    2014-11-01

    Doxazosin, a commonly prescribed treatment for patients with benign prostatic hyperplasia, serves as an α1-blocker of the adrenergic receptors. In this study, we calculated its effect on the ovarian carcinoma cells. Doxazosin induces dose-dependent growth suppression and is additively activated through IFN-α or IFN-γ stimulation. They both enhanced G1 phase arrest, as well as the activity of caspase-3, and the reduction of cyclin D1 and CDK4 protein levels. Doxazosin growth suppression was abolished either by the Janus family of tyrosine kinase (JAK) or the signal transducer and activator of transcription (STAT) inhibitor treatment. The activity of JAK/STAT was dependent on the level of doxazosin, suggesting a requirement of doxazosin for the activation of JAK/STAT. Furthermore, doxazosin plus IFN-α or doxazosin plus IFN-γ additively suppressed the activation of the JAK/STAT signals through phosphorylation of JAK and STAT, thus affecting the activation of subsequent downstream signaling components PI3K, mTOR, 70S6K, and PKCδ. In vivo study demonstrated that doxazosin significantly suppressed tumor growth in an ovarian cancer cell xenograft mouse model, inducing apoptotic cell death by up-regulating the expression of p53, whereas c-Myc expression was markedly reduced. Our data indicate that doxazosin can modulate the apoptotic effects of IFN-α- and IFN-γ through the JAK/STAT signaling pathways. Collectively, we indicate that this action may be a potent chemotherapeutic property against ovarian carcinoma.

  15. 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.

    Science.gov (United States)

    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

  16. 5-AED Enhances Survival of Irradiated Mice in a G-CSF-Dependent Manner, Stimulates Innate Immune Cell Function, Reduces Radiation-Induced DNA Damage and Induces Genes that Modulate Cell Cycle Progression and Apoptosis

    Science.gov (United States)

    2012-07-22

    promotes survival of irradiated human hematopoietic progeni- tors in vitro through induction of Nuclear Factor-κB (NFκB)-dependent Granulocyte Colony...modulate cell cycle progression and apoptosis. INTRODUCTION Because of the increasing threat posed by nuclear weapons [1], there is a pressing need for both...being developed as a radioprotectant and therapeutic for ARS. The steroid induces resistance to a variety of infec- tions in animals [5–10], enhances

  17. Apoptosis and inflammation

    Directory of Open Access Journals (Sweden)

    C. Haanen

    1995-01-01

    Full Text Available During the last few decades it has been recognized that cell death is not the consequence of accidental injury, but is the expression of a cell suicide programme. Kerr et al. (1972 introduced the term apoptosis. This form of cell death is under the influence of hormones, growth factors and cytokines, which depending upon the receptors present on the target cells, may activate a genetically controlled cell elimination process. During apoptosis the cell membrane remains intact and the cell breaks into apoptotic bodies, which are phagocytosed. Apoptosis, in contrast to necrosis, is not harmful to the host and does not induce any inflammatory reaction. The principal event that leads to inflammatory disease is cell damage, induced by chemical/physical injury, anoxia or starvation. Cell damage means leakage of cell contents into the adjacent tissues, resulting in the capillary transmigration of granulocytes to the injured tissue. The accumulation of neutrophils and release of enzymes and oxygen radicals enhances the inflammatory reaction. Until now there has been little research into the factors controlling the accumulation and the tissue load of granulocytes and their histotoxic products in inflammatory processes. Neutrophil apoptosis may represent an important event in the control of intlamtnation. It has been assumed that granulocytes disintegrate to apoptotic bodies before their fragments are removed by local macrophages. Removal of neutrophils from the inflammatory site without release of granule contents is of paramount importance for cessation of inflammation. In conclusion, apoptotic cell death plays an important role in inflammatory processes and in the resolution of inflammatory reactions. The facts known at present should stimulate further research into the role of neutrophil, eosinophil and macrophage apoptosis in inflammatory diseases.

  18. Enhanced stability of Mcl1, a prosurvival Bcl2 relative, blunts stress-induced apoptosis, causes male sterility, and promotes tumorigenesis.

    Science.gov (United States)

    Okamoto, Toru; Coultas, Leigh; Metcalf, Donald; van Delft, Mark F; Glaser, Stefan P; Takiguchi, Megumi; Strasser, Andreas; Bouillet, Philippe; Adams, Jerry M; Huang, David C S

    2014-01-07

    The B-cell CLL/lymphoma 2 (Bcl2) relative Myeloid cell leukemia sequence 1 (Mcl1) is essential for cell survival during development and for tissue homeostasis throughout life. Unlike Bcl2, Mcl1 turns over rapidly, but the physiological significance of its turnover has been unclear. We have gained insight into the roles of Mcl1 turnover in vivo by analyzing mice harboring a modified allele of Mcl1 that serendipitously proved to encode an abnormally stabilized form of Mcl1 due to a 13-aa N-terminal extension. Although the mice developed normally and appeared unremarkable, the homozygous males unexpectedly proved infertile due to defective spermatogenesis, which was evoked by enhanced Mcl1 prosurvival activity. Under unstressed conditions, the modified Mcl1 is present at levels comparable to the native protein, but it is markedly stabilized in cells subjected to stresses, such as protein synthesis inhibition or UV irradiation. Strikingly, the modified Mcl1 allele could genetically complement the loss of Bcl2, because introduction of even a single allele significantly ameliorated the severe polycystic kidney disease and consequent runting caused by Bcl2 loss. Significantly, the development of c-MYC-induced acute myeloid leukemia was also accelerated in mice harboring that Mcl1 allele. Our collective findings reveal that, under certain circumstances, the N terminus of Mcl1 regulates its degradation; that some cell types require degradation of Mcl1 to induce apoptosis; and, most importantly, that rapid turnover of Mcl1 can serve as a tumor-suppressive mechanism.

  19. Ethanolic extract of Thevetia peruviana flowers enhances TNF-α and TRAIL-induced apoptosis of human cervical cancer cells via intrinsic and extrinsic pathways

    Science.gov (United States)

    Managit, Chittima; Sakurai, Hiroaki; Saiki, Ikuo

    2017-01-01

    Tumor necrosis factor-α (TNF-α) and TNF-related apoptosis-inducing ligand (TRAIL) are promising candidates for cancer treatment due to their ability to induce apoptosis through death receptor stimulation. However, their usage may be limited due to the resistance of cancer cells to TNF-α- and TRAIL-induced apoptosis. Currently, there is interest in screening for natural products that can sensitize cancer cells to TNF-α- and TRAIL-induced apoptosis for their use in combination with TNF-α or TRAIL. It was previously reported that the bark extract of Thevetia peruviana showed a reversal effect on TRAIL-resistance in human gastric adenocarcinoma cell lines. In the present study, the effects of the ethanolic extract of T. peruviana flowers on TNF-α- and TRAIL-induced apoptosis of human cervical cancer HeLa cells were investigated in vitro by determining cell viability and apoptosis using a WST-1 cell proliferation assay and immunoblot analysis, respectively. The ethanolic extract of T. peruviana flowers promoted TNF-α and TRAIL-mediated cell death through the activation of the caspase cascade, poly(ADP-ribose) polymerase and BH3-interacting domain death agonist cleavage. Combined treatment using the extract plus TNF-α resulted in downregulation of anti-apoptotic protein, including myeloid cell leukemia sequence-1, B-cell lymphoma-extra large (Bcl-XL), X-linked inhibitor of apoptosis protein and survivin, while the combined treatment with TRAIL downregulated Bcl-XL. Thus, the ethanolic extract of T. peruviana flowers has potential in sensitizing the TNF-α- and TRAIL-induced apoptosis of HeLa cells via the intrinsic and extrinsic pathways. PMID:28454468

  20. Ganoderic acid Me induces the apoptosis of competent T cells and increases the proportion of Treg cells through enhancing the expression and activation of indoleamine 2,3-dioxygenase in mouse lewis lung cancer cells.

    Science.gov (United States)

    Que, Zujun; Zou, Fangyuan; Zhang, Anle; Zheng, Yuanhong; Bi, Ling; Zhong, Jianjiang; Tian, Jianhui; Liu, Jianwen

    2014-11-01

    The indoleamine 2,3-dioxygenase-(IDO-) mediated microenvironment plays an important role in tumor immune escape. It is known that ganoderic acid Me can enhance IFN-γ expression and IDO is preferentially induced by IFN-γ. However, whether GA-Me can induce IDO expression has not been clarified yet. We established stable clones of IDO-overexpressing 2 LL cells (2LL-EGFP-IDO). After co-culturing with IDO expressing or control vector-transfected 2LL-EGFP cells, T cell apoptosis was determined and the proportion of the regulatory T cells (Tregs) and CD8+ T cell subset was measured. The total cellular protein samples of 2 LL-EGFP-IDO cells were isolated for detecting JAK-STAT1 signalling pathway. Co-culture supernatants were used to detect amino acids and cytokines. IDO transfected 2 LL cells yielded high level of IDO enzymatic activity, resulting in complete depletion of tryptophan from the culture medium. We found that apoptosis occurred in T cells after cocultured with IDO+2LL cells and the proportion of CD4+CD25+ cells and FoxP3+ cells increased while CD8+ cells decreased. The specific inhibitor of IDO, 1-D-MT and GA-Me efficiently enhanced T cell apoptosis, increased Tregs, and reduced CD8+ T cells in vitro. Increased expression of IDO, p-JAK1 and p-STAT1 were confirmed by Western blot analysis. The levels of IFN-γ, IL-10, LDH and kynurenine in co-culture supernatant correspondingly increased, while tryptophan reduced. These results suggest that GA-Me contributing to IDO helps to create a tolerogenic milieu in lung tumors by directly inducing T cell apoptosis, restraining CD8+ T cell activation, and enhancing Treg-mediated immunosuppression. Copyright © 2014 Elsevier B.V. All rights reserved.

  1. Reactivating p53 and Inducing Tumor Apoptosis (RITA Enhances the Response of RITA-Sensitive Colorectal Cancer Cells to Chemotherapeutic Agents 5-Fluorouracil and Oxaliplatin

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    Armin Wiegering

    2017-04-01

    Full Text Available Colorectal carcinoma (CRC is the most common cancer of the gastrointestinal tract with frequently dysregulated intracellular signaling pathways, including p53 signaling. The mainstay of chemotherapy treatment of CRC is 5-fluorouracil (5FU and oxaliplatin. The two anticancer drugs mediate their therapeutic effect via DNA damage-triggered signaling. The small molecule reactivating p53 and inducing tumor apoptosis (RITA is described as an activator of wild-type and reactivator of mutant p53 function, resulting in elevated levels of p53 protein, cell growth arrest, and cell death. Additionally, it has been shown that RITA can induce DNA damage signaling. It is expected that the therapeutic benefits of 5FU and oxaliplatin can be increased by enhancing DNA damage signaling pathways. Therefore, we highlighted the antiproliferative response of RITA alone and in combination with 5FU or oxaliplatin in human CRC cells. A panel of long-term established CRC cell lines (n = 9 including p53 wild-type, p53 mutant, and p53 null and primary patient-derived, low-passage cell lines (n = 5 with different p53 protein status were used for this study. A substantial number of CRC cells with pronounced sensitivity to RITA (IC50< 3.0 μmol/l were identified within established (4/9 and primary patient-derived (2/5 CRC cell lines harboring wild-type or mutant p53 protein. Sensitivity to RITA appeared independent of p53 status and was associated with an increase in antiproliferative response to 5FU and oxaliplatin, a transcriptional increase of p53 targets p21 and NOXA, and a decrease in MYC mRNA. The effect of RITA as an inducer of DNA damage was shown by a strong elevation of phosphorylated histone variant H2A.X, which was restricted to RITA-sensitive cells. Our data underline the primary effect of RITA, inducing DNA damage, and demonstrate the differential antiproliferative effect of RITA to CRC cells independent of p53 protein status. We found a substantial number

  2. Induction of Apoptosis and Cell Cycle Arrest by Flavokawain C on HT-29 Human Colon Adenocarcinoma via Enhancement of Reactive Oxygen Species Generation, Upregulation of p21, p27, and GADD153, and Inactivation of Inhibitor of Apoptosis Proteins.

    Science.gov (United States)

    Phang, Chung-Weng; Karsani, Saiful Anuar; Abd Malek, Sri Nurestri

    2017-07-01

    Chalcones have been shown to exhibit anti-cancer properties by targeting multiple molecular pathways. It was, therefore, of interest to investigate flavokawain C (FKC), a naturally occurring chalcone, which can be isolated from Kava (Piper methysticum Forst) root extract. The aim of this study was to investigate the inhibitory effect of FKC on the growth of HT-29 cells and its underlying mechanism of action. Cell viability of HT-29 cells was assessed by Sulforhodamine B assay after FKC treatment. Induction of apoptosis was examined by established morphological and biochemical assays. ROS generation was determined by dichlorofluorescein fluorescence staining, and superoxide dismutase activity was measured using the spectrophotometric method. Western blotting was used to examine the changes in the protein levels. FKC markedly decreased the cell viability of HT-29 cells and the cells showed dramatic changes in cellular and nuclear morphologies with typical apoptotic features. The induction of apoptosis correlated well with the externalization of phosphatidylserine, DNA fragmentation, decreased mitochondrial membrane potential, activation of caspases, and PARP cleavage. This was associated with an increase in reactive oxygen species and a decrease in SOD activity. The protein levels of XIAP, c-IAP1, and c-IAP2 were downregulated, whereas the GADD153 was upregulated after FKC treatment. FKC induced cell cycle arrest at the G1 and G2/M phases via upregulation of p21 and p27 in a p53-independent manner. Our results provide evidence that FKC has the potential to be developed into chemotherapeutic drug for the treatment of colon adenocarcinoma. Flavokawain C inhibited the growth of HT-29 human colon adenocarcinoma cellsFlavokawain C induced apoptosis in HT-29 cells, associated with an increase in reactive oxygen species and a decrease in SOD activityFlavokawain C induced cell cycle arrest at the G1 and G2/M phases via upregulation of p21 and p27 in HT-29 cellsHT-29 cells

  3. Physical exercise promotes memory capability by enhancing hippocampal mitochondrial functions and inhibiting apoptosis in obesity-induced insulin resistance by high fat diet.

    Science.gov (United States)

    Park, Hye-Sang; Cho, Han-Sam; Kim, Tae-Woon

    2018-02-01

    A high-fat diet induces obesity in mice, leading to insulin resistance, decreased mitochondrial function, and increased apoptosis in the hippocampus, which eventually result in memory loss. The present study investigated the effect of physical exercise on memory, hippocampal mitochondrial function, and apoptosis in mice with in insulin resistance caused by obesity due to high-fat diet. Mice were randomly divided into four groups: control (CON), control and exercise (CON + EX), high fat diet (HFD), and high fat diet and exercise (HFD + EX). After receiving a high-fat (60%) diet for 20 weeks to induce obesity, the animals were subjected to an exercise routine 6 times per week, for 12 weeks. The exercise duration and intensity gradually increased over 4-week intervals. Hippocampal memory was examined using the step-down avoidance task. Mitochondrial function and apoptosis were also examined in the hippocampus and dentate gyrus. We found that obesity owing to a high-fat diet induced insulin resistance and caused a decrease in memory function. Insulin resistance also caused a decrease in mitochondrial function in the hippocampus by reducing Ca 2+ retention and O 2, respiration, increasing the levels of H 2 O 2 , and Cyp-D, and mPTP opening. In addition, apoptosis in the hippocampus increased owing to decreased expression of Bcl-2 and increased expression of Bax, cytochrome c, and caspase-3 and TUNEL-positive cells. In contrast, physical exercise led to reduced insulin resistance, improved mitochondrial function, and reduced apoptosis in the hippocampus. The results suggest that physiological stimulations such as exercise improve hippocampal function and suppress apoptosis, potentially preventing the memory loss associated with obesity-induced insulin resistance.

  4. The SMRT coregulator enhances growth of estrogen receptor-α-positive breast cancer cells by promotion of cell cycle progression and inhibition of apoptosis.

    Science.gov (United States)

    Blackmore, Julia K; Karmakar, Sudipan; Gu, Guowei; Chaubal, Vaishali; Wang, Liguo; Li, Wei; Smith, Carolyn L

    2014-09-01

    The SMRT coregulator functions as a dual coactivator and corepressor for estrogen receptor-α (ERα) in a gene-specific manner, and in several studies its elevated expression correlates with poor outcome for breast cancer patients. A specific role of SMRT in breast cancer progression has not been elucidated, but SMRT knock-down limits estradiol-dependent growth of MCF-7 breast cancer cells. In this study, small-interfering RNA (siRNA) and short-hairpin RNA (shRNA) approaches were used to determine the effects of SMRT depletion on growth of ERα-positive MCF-7 and ZR-75-1 breast cancer cells, as well as the ERα-negative MDA-MB-231 breast cancer line. Depletion of SMRT inhibited growth of ERα-positive cells grown in monolayer but had no effect on growth of the ERα-negative cells. Reduced SMRT levels also negatively impacted the anchorage-independent growth of MCF-7 cells as assessed by soft agar colony formation assays. The observed growth inhibitions were due to a loss of estradiol-induced progression through the G1/S transition of the cell cycle and increased apoptosis in SMRT-depleted compared with control cells. Gene expression analyses indicated that SMRT inhibits apoptosis by a coordinated regulation of genes involved in apoptosis. Functioning as a dual coactivator for anti-apoptotic genes and corepressor for pro-apoptotic genes, SMRT can limit apoptosis. Together these data indicate that SMRT promotes breast cancer progression through multiple pathways leading to increased proliferation and decreased apoptosis.

  5. Endoplasmic reticulum stress could induce autophagy and apoptosis and enhance chemotherapy sensitivity in human esophageal cancer EC9706 cells by mediating PI3K/Akt/mTOR signaling pathway.

    Science.gov (United States)

    Zhou, Fang; Li, Yan-Hua; Wang, Jian-Jun; Pan, Jia; Lu, Hong

    2017-06-01

    The study was designed to explore the mechanism of tunicamycin-induced endoplasmic reticulum stress in human esophageal cancer EC9706 cells and EC109 cells, as well as its effects on cell autophagy, apoptosis, and chemoresistance. Tunicamycin-induced endoplasmic reticulum stress model was established in EC9706 and EC109 cell lines. Western blotting was employed to detect the expression of endoplasmic reticulum stress iconic protein GRP78. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay was used to evaluate the effect of different cisplatin and tunicamycin concentrations on survival rate of EC9706 cells and EC109 cells. Autophagy was monitored using monodansylcadaverin and apoptosis was detected by flow cytometry. Western blotting was used to detect the expressions of endoplasmic reticulum stress-related proteins (PERK, eIF2α, and CHOP), PI3K/Akt/mTOR signaling pathway-related proteins, autophagy-related proteins (LC3-I/LC3-II, Beclin-1, and p62), and apoptosis-related proteins (Bcl-2, Bax, and cleaved caspase-3). Tunicamycin led to increased expression of GRP78. With tunicamycin treatment, phosphorylation of PERK and eIF2α and CHOP expression increased. Meanwhile, the increase in cytolysosome was concentration and time dependent. With the increased tunicamycin concentration, there were increased expressions of Bax and cleaved caspase-3, decreased expression of Bcl-2, and lower phosphorylation of PI3K/Akt/mTOR signaling pathway-related proteins. Therefore, it can be concluded that the combination of tunicamycin and cisplatin could improve the sensitivity of EC9706 cells and EC109 cells to cisplatin; PI3K inhibitor BEZ235 could enhance cell autophagy and apoptosis and increase cell sensitivity to cisplatin.

  6. Enhanced efficacy of combined 213Bi-DTPA-F3 and paclitaxel therapy of peritoneal carcinomatosis is mediated by enhanced induction of apoptosis and G2/M phase arrest.

    Science.gov (United States)

    Vallon, Mario; Seidl, Christof; Blechert, Birgit; Li, Zhoulei; Gilbertz, Klaus-Peter; Baumgart, Anja; Aichler, Michaela; Feuchtinger, Annette; Gaertner, Florian C; Bruchertseifer, Frank; Morgenstern, Alfred; Walch, Axel K; Senekowitsch-Schmidtke, Reingard; Essler, Markus

    2012-12-01

    Targeted therapy with α-particle emitting radionuclides is a promising new option in cancer therapy. Stable conjugates of the vascular tumour-homing peptide F3 with the α-emitter (213)Bi specifically target tumour cells. The aim of our study was to determine efficacy of combined (213)Bi-diethylenetriaminepentaacetic acid (DTPA)-F3 and paclitaxel treatment compared to treatment with either (213)Bi-DTPA-F3 or paclitaxel both in vitro and in vivo. Cytotoxicity of treatment with (213)Bi-DTPA-F3 and paclitaxel, alone or in combination, was assayed towards OVCAR-3 cells using the alamarBlue assay, the clonogenic assay and flow cytometric analyses of the mode of cell death and cell cycle arrest. Therapeutic efficacy of the different treatment options was assayed after repeated treatment of mice bearing intraperitoneal OVCAR-3 xenograft tumours. Therapy monitoring was performed by bioluminescence imaging and histopathologic analysis. Treatment of OVCAR-3 cells in vitro with combined (213)Bi-DTPA-F3 and paclitaxel resulted in enhanced cytotoxicity, induction of apoptosis and G2/M phase arrest compared to treatment with either (213)Bi-DTPA-F3 or paclitaxel. Accordingly, i.p. xenograft OVCAR-3 tumours showed the best response following repeated (six times) combined therapy with (213)Bi-DTPA-F3 (1.85 MBq) and paclitaxel (120 μg) as demonstrated by bioluminescence imaging and histopathologic investigation of tumour spread on the mesentery of the small and large intestine. Moreover, mean survival of xenograft mice that received combined therapy with (213)Bi-DTPA-F3 and paclitaxel was significantly superior to mice treated with either (213)Bi-DTPA-F3 or paclitaxel alone. Combined treatment with (213)Bi-DTPA-F3 and paclitaxel significantly increased mean survival of mice with peritoneal carcinomatosis of ovarian origin, thus favouring future therapeutic application.

  7. Enhanced efficacy of combined {sup 213}Bi-DTPA-F3 and paclitaxel therapy of peritoneal carcinomatosis is mediated by enhanced induction of apoptosis and G2/M phase arrest

    Energy Technology Data Exchange (ETDEWEB)

    Vallon, Mario; Seidl, Christof; Blechert, Birgit; Li, Zhoulei; Gaertner, Florian C.; Senekowitsch-Schmidtke, Reingard; Essler, Markus [Technische Universitaet Muenchen, Department of Nuclear Medicine, Munich (Germany); Gilbertz, Klaus-Peter [German Armed Forces, Institute of Radiobiology, Munich (Germany); Baumgart, Anja [Technische Universitaet Muenchen, III. Medical Department, Munich (Germany); Aichler, Michaela; Feuchtinger, Annette; Walch, Axel K. [Helmholtz Zentrum Muenchen, Institute of Pathology, Neuherberg (Germany); Bruchertseifer, Frank; Morgenstern, Alfred [Institute for Transuranium Elements, European Commission, Joint Research Centre, Karlsruhe (Germany)

    2012-12-15

    Targeted therapy with {alpha}-particle emitting radionuclides is a promising new option in cancer therapy. Stable conjugates of the vascular tumour-homing peptide F3 with the {alpha}-emitter {sup 213}Bi specifically target tumour cells. The aim of our study was to determine efficacy of combined {sup 213}Bi-diethylenetriaminepentaacetic acid (DTPA)-F3 and paclitaxel treatment compared to treatment with either {sup 213}Bi-DTPA-F3 or paclitaxel both in vitro and in vivo. Cytotoxicity of treatment with {sup 213}Bi-DTPA-F3 and paclitaxel, alone or in combination, was assayed towards OVCAR-3 cells using the alamarBlue assay, the clonogenic assay and flow cytometric analyses of the mode of cell death and cell cycle arrest. Therapeutic efficacy of the different treatment options was assayed after repeated treatment of mice bearing intraperitoneal OVCAR-3 xenograft tumours. Therapy monitoring was performed by bioluminescence imaging and histopathologic analysis. Treatment of OVCAR-3 cells in vitro with combined {sup 213}Bi-DTPA-F3 and paclitaxel resulted in enhanced cytotoxicity, induction of apoptosis and G2/M phase arrest compared to treatment with either {sup 213}Bi-DTPA-F3 or paclitaxel. Accordingly, i.p. xenograft OVCAR-3 tumours showed the best response following repeated (six times) combined therapy with {sup 213}Bi-DTPA-F3 (1.85 MBq) and paclitaxel (120 {mu}g) as demonstrated by bioluminescence imaging and histopathologic investigation of tumour spread on the mesentery of the small and large intestine. Moreover, mean survival of xenograft mice that received combined therapy with {sup 213}Bi-DTPA-F3 and paclitaxel was significantly superior to mice treated with either {sup 213}Bi-DTPA-F3 or paclitaxel alone. Combined treatment with {sup 213}Bi-DTPA-F3 and paclitaxel significantly increased mean survival of mice with peritoneal carcinomatosis of ovarian origin, thus favouring future therapeutic application. (orig.)

  8. Apoptosis and Molecular Targeting Therapy in Cancer

    Science.gov (United States)

    Hassan, Mohamed; Watari, Hidemichi; AbuAlmaaty, Ali; Ohba, Yusuke; Sakuragi, Noriaki

    2014-01-01

    Apoptosis is the programmed cell death which maintains the healthy survival/death balance in metazoan cells. Defect in apoptosis can cause cancer or autoimmunity, while enhanced apoptosis may cause degenerative diseases. The apoptotic signals contribute into safeguarding the genomic integrity while defective apoptosis may promote carcinogenesis. The apoptotic signals are complicated and they are regulated at several levels. The signals of carcinogenesis modulate the central control points of the apoptotic pathways, including inhibitor of apoptosis (IAP) proteins and FLICE-inhibitory protein (c-FLIP). The tumor cells may use some of several molecular mechanisms to suppress apoptosis and acquire resistance to apoptotic agents, for example, by the expression of antiapoptotic proteins such as Bcl-2 or by the downregulation or mutation of proapoptotic proteins such as BAX. In this review, we provide the main regulatory molecules that govern the main basic mechanisms, extrinsic and intrinsic, of apoptosis in normal cells. We discuss how carcinogenesis could be developed via defective apoptotic pathways or their convergence. We listed some molecules which could be targeted to stimulate apoptosis in different cancers. Together, we briefly discuss the development of some promising cancer treatment strategies which target apoptotic inhibitors including Bcl-2 family proteins, IAPs, and c-FLIP for apoptosis induction. PMID:25013758

  9. Intramyocardial Injection of Recombinant Adeno-Associated Viral Vector Coexpressing PR39/Adrenomedullin Enhances Angiogenesis and Reduces Apoptosis in a Rat Myocardial Infarction Model

    Directory of Open Access Journals (Sweden)

    Rui An

    2017-01-01

    Full Text Available Cotransfer of angiogenic and antiapoptotic genes could be the basis of new gene therapy strategies for myocardial infarction. In this study, rAAV-PR39-ADM, coexpressing antimicrobial peptide (PR39 and adrenomedullin (ADM, was designed with the mediation of recombinant adeno-associated virus. In vitro, CRL-1730 cells were divided into four groups, namely, the sham group, the AAV-null group, the NS (normal saline group, and the PR39-ADM group. Immunocytochemistry analysis, CCK-8 assays, Matrigel assays, and apoptotic analysis were performed; in vivo, myocardial infarction model was established through ligation of the left coronary artery on rats, and treatment groups corresponded to those used in vitro. Myocardial injury, cardiac performance, and the extent of myocardial apoptosis were assessed. Results suggested that rAAV-PR39-ADM administration after myocardial infarction improved cell viability and cardiac function, attenuated apoptosis and myocardial injury, and promoted angiogenesis. Subsequently, levels of 6×His, HIF-1α, VEGF, p-Akt, Akt, ADM, Bcl-2, and Bax were measured by western blot. rAAV-PR39-ADM increased p-Akt, HIF-1α, and VEGF levels and induced higher Bcl-2 expression and lower Bax expression. In conclusion, our results demonstrate that rAAV-PR39-ADM mitigates myocardial injury by promoting angiogenesis and reducing apoptosis. This study suggests a potential novel gene therapy-based method that could be used clinically for myocardial infarction.

  10. Postnatal treadmill exercise alleviates short-term memory impairment by enhancing cell proliferation and suppressing apoptosis in the hippocampus of rat pups born to diabetic rats.

    Science.gov (United States)

    Kim, Young Hoon; Sung, Yun-Hee; Lee, Hee-Hyuk; Ko, Il-Gyu; Kim, Sung-Eun; Shin, Mal-Soon; Kim, Bo-Kyun

    2014-08-01

    During pregnancy, diabetes mellitus exerts detrimental effects on the development of the fetus, especially the central nervous system. In the current study, we evaluated the effects of postnatal treadmill exercise on short-term memory in relation with cell proliferation and apoptosis in the hippocampus of rat pups born to streptozotocin (STZ)-induced diabetic maternal rats. Adult female rats were mated with male rats for 24 h. Two weeks after mating, the pregnant female rats were divided into two groups: control group and STZ injection group. The pregnant rats in the STZ injection group were administered 40 mg/kg of STZ intraperitoneally. After birth, the rat pups were divided into the following four groups: control group, control with postnatal exercise group, maternal STZ-injection group, and maternal STZ-injection with postnatal exercise group. The rat pups in the postnatal exercise groups were made to run on a treadmill for 30 min once a day, 5 times per week for 2 weeks beginning 4 weeks after birth. The rat pups born to diabetic rats were shown to have short-term memory impairment with suppressed cell proliferation and increased apoptosis in the hippocampal dentate gyrus. Postnatal treadmill exercise alleviated short-term memory impairment by increased cell proliferation and suppressed apoptosis in the rat pups born to diabetic rats. These findings indicate that postnatal treadmill exercise may be used as a valuable strategy to ameliorate neurodevelopmental problems in children born to diabetics.

  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

    Directory of Open Access Journals (Sweden)

    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. The Dietary Flavonoid Fisetin Causes Cell Cycle Arrest, Caspase-Dependent Apoptosis, and Enhanced Cytotoxicity of Chemotherapeutic Drugs in Triple-Negative Breast Cancer Cells.

    Science.gov (United States)

    Smith, Matthew L; Murphy, Kaylee; Doucette, Carolyn D; Greenshields, Anna L; Hoskin, David W

    2016-08-01

    Fisetin (3,3',4',7-tetrahydroxyflavone), a flavonoid found in a number of fruits and vegetables, has diverse biological activities, including cytotoxic effects on cancer cells. In this study, we investigated the effect of fisetin on triple-negative breast cancer (TNBC) cells. TNBC has a poorer prognosis than other types of breast cancer and treatment options for this disease are limited. Fisetin inhibited the growth of MDA-MB-468 and MDA-MB-231 TNBC cells, as well as their ability to form colonies, without substantially affecting the growth of non-malignant cells. In addition, fisetin inhibited the growth of estrogen receptor-bearing MCF-7 breast cancer cells and human epidermal growth factor receptor 2-overexpressing SK-BR-3 breast cancer cells. Fisetin inhibited TNBC cell division and induced apoptosis, which was associated with mitochondrial membrane permeabilization and the activation of caspase-9 and caspase-8, as well as the cleavage of poly(ADP-ribose) polymerase-1. Induction of caspase-dependent apoptosis by fisetin was confirmed by reduced killing of TNBC cells in the presence of the pan-caspase inhibitors Z-VAD-FMK and BOC-D-FMK. Decreased phosphorylation of histone H3 at serine 10 in fisetin-treated TNBC cells at G2/M phase of the cell cycle suggested that fisetin-induced apoptosis was the result of Aurora B kinase inhibition. Interestingly, the cytotoxic effect of cisplatin, 5-fluorouracil, and 4-hydroxycyclophosphamide metabolite of cyclophosphamide on TNBC cells was increased in the presence of fisetin. These findings suggest that further investigation of fisetin is warranted for possible use in the management of TNBC. J. Cell. Biochem. 117: 1913-1925, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  13. Nef-M1, a CXCR4 Peptide Antagonist, Enhances Apoptosis and Inhibits Primary Tumor Growth and Metastasis in Breast Cancer.

    Science.gov (United States)

    Bumpers, Harvey; Huang, Ming-Bo; Katkoori, Venkat; Manne, Upender; Bond, Vincent

    2013-06-01

    Results from studies with animal models suggest that, in many cancers, CXCR4 is an important therapeutic target and that CXCR4 antagonists may be promising treatments for primary cancers and for metastases. The Nef protein effectively competes with CXCR4's natural ligand, SDF-1α, and induces apoptosis. As described in this report, the Nef-M1 peptide (Nef protein amino acids 50 - 60) inhibits primary tumor growth and metastasis of breast cancer (BC). Four BC cell lines (MDA-MB-231, MDA-MB-468, MCF 7, and DU4475) and primary human mammary epithelium (HME) cells were evaluated for their response to the Nef protein and to the Nef-M1 peptide. The presence of CXCR4 receptors in these cells was determined by RT-PCR, Western blot (WB), and immunohistochemical analyses. The apoptotic effect of Nef-M1 was assessed by terminal transferase dUTP nick-end labeling (TUNEL). WBs was used to assess caspase 3 activation. BC xenografts grown in SCID mice were evaluated for the presence of CXCR4 and for their metastatic potential. CXCR4 was presented in MDA-MB-231, MCF 7, and DU 4475 BC cells but not in MDA-MB-468 BC or HME cells. Cells expressing CXCR4 and treated with Nef-M1 peptide or the Nef protein had higher rates of apoptosis than untreated cells. Caspase-3 activation increased in MDA-MB 231 cells treated with the Nef protein, the Nef 41 - 60 peptide, or Nef-M1. Nef-M1, administered to mice starting at the time of xenograft implantation, inhibited growth of primary tumors and metastatic spread. Untreated mice developed diffuse intraperitoneal metastases. We conclude that, in BCs, Nef-M1, through interaction with CXCR4, inhibits primary tumor growth and metastasis by causing apoptosis.

  14. Indomethacin-Enhanced Anticancer Effect of Arsenic Trioxide in A549 Cell Line: Involvement of Apoptosis and Phospho-ERK and p38 MAPK Pathways

    Directory of Open Access Journals (Sweden)

    Ali Mandegary

    2013-01-01

    Full Text Available Background. Focusing on novel drug combinations that target different pathways especially apoptosis and MAPK could be a rationale for combination therapy in successful treatment of lung cancer. Concurrent use of cyclooxygenase (COX inhibitors with arsenic trioxide (ATO might be a possible treatment option. Methods. Cytotoxicity of ATO, dexamethasone (Dex, celecoxib (Cel, and Indomethacin (Indo individually or in combination was determined at 24, 48, and 72 hrs in A549 lung cancer cells. The COX-2 gene and protein expression, MAPK pathway proteins, and caspase-3 activity were studied for the most cytotoxic combinations. Results. The IC50s of ATO and Indo were 68.7 μmol/L and 396.5 μmol/L, respectively. Treatment of cells with combinations of clinically relevant concentrations of ATO and Indo resulted in greater growth inhibition and apoptosis induction than did either agent alone. Caspase-3 activity was considerably high in the presence of ATO and Indo but showed no difference in single or combination use. Phosphorylation of p38 and ERK1/2 was remarkable in the concurrent presence of both drugs. Conclusions. Combination therapy with ATO and Indo exerted a very potent in vitro cytotoxic effect against A549 lung cancer cells. Activation of ERK and p38 pathways might be the mechanism of higher cytotoxic effect of ATO-Indo combination.

  15. Cucurbitacin B inhibits proliferation, induces G2/M cycle arrest and autophagy without affecting apoptosis but enhances MTT reduction in PC12 cells

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    Chuanhong Wu

    2016-03-01

    Full Text Available In the present study, the effect of cucurbitacin B (a natural product with anti-cancer effect was studied on PC12 cells. It significantly reduced the cell number, changed cell morphology and inhibited colony formation while MTT results showed increased cell viability. Cucurbitacin B treatment increased activity of succinode hydrogenase. No alteration in the integrity of mem-brane, the release of lactic dehydrogenase, the mitochondrial membrane potential, and the expression of apoptotic proteins suggested that cucurbitacin B did not induce apoptosis. The cell cycle was remarkably arrested at G2/M phase. Furthermore, cucurbitacin B induced autophagy as evidence by accumulation of autophagic vacuoles and the increase of LC3II. In addition, cucurbitacin B up-regulated the expression of p-beclin-1, p-ULK1, p-Wee1, p21 and down-regulated p-mTOR, p-p70S6K, CDC25C, CDK1, Cyclin B1. In conclusion, cucurbitacin B inhibited PC12 proliferation but caused MTT pitfall. Cucurbitacin B induced G2/M cell cycle arrest, autophagy, but not the apoptosis in PC12 cells.

  16. Spontaneous liver fibrosis induced by long term dietary vitamin D deficiency in adult mice is related to chronic inflammation and enhanced apoptosis.

    Science.gov (United States)

    Zhu, Longdong; Kong, Ming; Han, Yuan-Ping; Bai, Li; Zhang, Xiaohui; Chen, Yu; Zheng, Sujun; Yuan, Hong; Duan, Zhongping

    2015-05-01

    Epidemiological studies have revealed an association between vitamin D deficiency and various chronic liver diseases. However, it is not known whether lack of vitamin D can induce spontaneous liver fibrosis in an animal model. To study this, mice were fed either a control diet or a vitamin D deficient diet (VDD diet). For the positive control, liver fibrosis was induced with carbon tetrachloride. Here we show, for the first time, that liver fibrosis spontaneously developed in mice fed the VDD diet. Long-term administration of a VDD diet resulted in necro-inflammation and liver fibrosis. Inflammatory mediators including tumor necrosis factor-α, interleulin-1, interleukin-6, Toll-like-receptor 4, and monocyte chemotactic protein-1 were up-regulated in the livers of the mice fed the VDD diet. Conversely, the expression of Th2/M2 markers such as IL-10, IL-13, arginase 1, and heme oxygenase-1 were down-regulated in the livers of mice fed the VDD diet. Transforming growth factor-β1 and matrix metalloproteinase 13, which are important for fibrosis, were induced in the livers of mice fed the VDD diet. Moreover, the VDD diet triggered apoptosis in the parenchymal cells, in agreement with the increased levels of Fas and FasL, and decreased Bcl2 and Bclx. Thus, long-term vitamin D deficiency can provoke chronic inflammation that can induce liver apoptosis, which consequently activates hepatic stellate cells to initiate liver fibrosis.

  17. Enhanced endoplasmic reticulum SERCA activity by overexpression of hepatic stimulator substance gene prevents hepatic cells from ER stress-induced apoptosis.

    Science.gov (United States)

    Zhang, Jing; Li, Yuan; Jiang, Shujun; Yu, Hao; An, Wei

    2014-02-01

    Although the potential pathogenesis of nonalcoholic fatty liver disease (NAFLD) is unclear, increasing evidence indicates that endoplasmic reticulum (ER) stress may link free fatty acids to NAFLD. Since we previously reported that hepatic stimulator substance (HSS) could protect the liver from steatosis, this study is aimed to investigate whether HSS protection could be related with its inhibition on ER stress. The HSS gene was stably transfected into BEL-7402 hepatoma cells and effectively expressed in ER. The palmitic acid (PA)-induced heptocyte lipotoxicity was reproduced in the HSS-transfected cells, and HSS alleviation of the ER stress and apoptosis were subsequently examined. The results showed that PA treatment led to a heavy accumulation of fatty acids within the cells and a remarkable increase in reactive oxygen species (ROS). However, in the HSS-expressing cells, production of ROS was inhibited and ER stress-related marker glucose-regulated protein 78 (GRP-78), sterol regulatory element-binding protein (SREBP), anti-phospho-PRK-1ike ER kinase (p-PERK), anti-phospho-eukaryotic initiation factor 2α (p-eIF2α), and anti-C/EBP homologous protein (CHOP) were downregulated compared with the wild-type or mutant HSS-transfected cells. Furthermore, PA treatment severely impaired the activity of sarco-endoplasmic reticulum Ca(2+)-ATPase (SERCA), leading to imbalanced calcium homeostasis during ER stress, which could be rescued in the HSS-trasfected cells. The protection provided by HSS to the SERCA is identical to that observed with N-acetyl-l-cysteine (NAC) and sodium dimercaptopropane sulfonate (Na-DMPS), which are two typical free radical scavengers. As a consequence, the rate of ER stress-mediated apoptosis in the HSS-expressing cells was significantly reduced. In conclusion, the protective effect of HSS against ER stress may be associated with the removal of ROS to restore the activity of the SERCA.

  18. Phycocyanin-Functionalized Selenium Nanoparticles Reverse Palmitic Acid-Induced Pancreatic β Cell Apoptosis by Enhancing Cellular Uptake and Blocking Reactive Oxygen Species (ROS)-Mediated Mitochondria Dysfunction.

    Science.gov (United States)

    Liu, Chang; Fu, Yuanting; Li, Chang-E; Chen, Tianfeng; Li, Xiaoling

    2017-06-07

    Accumulation of palmitic acid (PA) in human bodies could cause damage to pancreatic β cells and lead to chronic diseases by generation of reactive oxygen species (ROS). Therefore, it is of great significance to search for nutrition-available agents with antioxidant activity to protect pancreatic islet cells against PA-induced damage. Phycocyanin (PC) and selenium (Se) have been reported to have excellent antioxidant activity. In this study, PC-functionalized selenium nanoparticles (PC-SeNPs) were synthesized to investigate the in vitro protective effects on INS-1E rat insulinoma β cells against PA-induced cell death. A potent protective effect was achieved by regulation of particle size and PC content. Among three PC-SeNPs (165, 235, and 371 nm), PC-SeNPs-235 nm showed the highest cellular uptake and the best protective activities. For cell cycle analysis, PC-SeNPs showed a better protective effect on PA-induced INS-1E cell apoptosis than PC or SeNPs, and PC-SeNPs-235 nm exhibited the best effect. Further mechanistic studies demonstrated that PA induced overproduction of intracellular ROS, mitochondria fragmentation, activation of caspase-3, -8, and -9, and cleavage of PARP. However, pretreatment of the cells with PC-SeNPs effectively blocked these intracellular events, which suggests that PC-SeNPs could protect INS-1E cells against PA-induced cell apoptosis via attenuating oxidative stress and downstream signaling pathways. This finding provides a great promising nutritional approach for protection against diseases related to islet damage.

  19. PEGylated TNF-related apoptosis-inducing ligand (TRAIL)-loaded sustained release PLGA microspheres for enhanced stability and antitumor activity.

    Science.gov (United States)

    Kim, Tae Hyung; Jiang, Hai Hua; Park, Chan Woong; Youn, Yu Seok; Lee, Seulki; Chen, Xiaoyuan; Lee, Kang Choon

    2011-02-28

    The purpose of this work was to develop an effective PEGylated TNF-related apoptosis-inducing ligand (PEG-TRAIL) delivery system for antitumor therapy based on local injection to tumor sites that has a sustained effect without protein aggregation or an initial release burst. The authors designed poly (lactic-co-glycolic) acid (PLGA) microspheres that deliver PEG-TRAIL locally and continuously at tumor sites with sustained biological activity and compared its performance with that of TRAIL microspheres. TRAIL or PEG-TRAIL was microencapsulated into PLGA microspheres using a double-emulsion solvent extraction method. Prepared TRAIL and PEG-TRAIL microspheres showed entirely spherical, smooth surfaces. However, PEG-TRAIL microspheres exhibited a 2.07-fold higher encapsulation efficiency than TRAIL microspheres, and exhibited a tri-phasic in vitro release profile with a lower initial burst (15.8%) than TRAIL microspheres (42.7%). Furthermore, released PEG-TRAIL showed a continued ability to induce apoptosis over 14 days. In vivo pharmacokinetic studies also demonstrated that PEG-TRAIL microspheres had a sustained release profile (18 days), and that the steady-state concentration of PEG-TRAIL in rat plasma was reached at day 3 and maintained until day 15; its steady-state concentration in rat plasma changed from 1444.3 ± 338.4 to 2697.7 ± 419.7 pg/ml. However, TRAIL microspheres were released out within 2 days after administration. Finally, in vivo antitumor tests revealed that tumor growths were significantly more inhibited by a single dose of PEG-TRAIL microspheres than TRAIL microspheres when delivered at 300 μg of TRAIL/mouse. Tumors taken from mouse treated with PEG-TRAIL microspheres showed 78.3% tumor suppression at 24 days, and this was 3.02-fold higher than that observed for TRAIL microspheres (25.9% tumor inhibition). Furthermore, these improved pharmaceutical characteristics of PEG-TRAIL microspheres resulted in superior therapeutic effects without

  20. MiR-34a/c-Dependent PDGFR-α/β Downregulation Inhibits Tumorigenesis and Enhances TRAIL-Induced Apoptosis in Lung Cancer.

    Directory of Open Access Journals (Sweden)

    Michela Garofalo

    Full Text Available Lung cancer is the leading cause of cancer mortality in the world today. Although some advances in lung cancer therapy have been made, patient survival is still poor. MicroRNAs (miRNAs can act as oncogenes or tumor-suppressor genes in human malignancy. The miR-34 family consists of tumor-suppressive miRNAs, and its reduced expression has been reported in various cancers, including non-small cell lung cancer (NSCLC. In this study, we found that miR-34a and miR-34c target platelet-derived growth factor receptor alpha and beta (PDGFR-α and PDGFR-β, cell surface tyrosine kinase receptors that induce proliferation, migration and invasion in cancer. MiR-34a and miR-34c were downregulated in lung tumors compared to normal tissues. Moreover, we identified an inverse correlation between PDGFR-α/β and miR-34a/c expression in lung tumor samples. Finally, miR-34a/c overexpression or downregulation of PDGFR-α/β by siRNAs, strongly augmented the response to TNF-related apoptosis inducing ligand (TRAIL while reducing migratory and invasive capacity of NSCLC cells.

  1. Sorafenib analogue SC-60 induces apoptosis through the SHP-1/STAT3 pathway and enhances docetaxel cytotoxicity in triple-negative breast cancer cells.

    Science.gov (United States)

    Liu, Chun-Yu; Su, Jung-Chen; Huang, Tzu-Ting; Chu, Pei-Yi; Huang, Chun-Teng; Wang, Wan-Lun; Lee, Chia-Han; Lau, Ka-Yi; Tsai, Wen-Chun; Yang, Hsiu-Ping; Shiau, Chung-Wai; Tseng, Ling-Ming; Chen, Kuen-Feng

    2017-03-01

    Recurrent triple-negative breast cancer (TNBC) needs new therapeutic targets. Src homology region 2 domain-containing phosphatase-1 (SHP-1) can act as a tumor suppressor by dephosphorylating oncogenic kinases. One major target of SHP-1 is STAT3, which is highly activated in TNBC. In this study, we tested a sorafenib analogue SC-60, which lacks angiokinase inhibition activity, but acts as a SHP-1 agonist, in TNBC cells. SC-60 inhibited proliferation and induced apoptosis by dephosphorylating STAT3 in both a dose- and time-dependent manner in TNBC cells (MDA-MB-231, MDA-MB-468, and HCC1937). By contrast, ectopic expression of STAT3 rescued the anticancer effect induced by SC-60. SC-60 also increased the SHP-1 activity, but this effect was inhibited when the N-SH2 domain (DN1) was deleted or with SHP-1 point mutation (D61A), implying that SHP-1 is the major target of SC-60 in TNBC. The use of SC-60 in combination with docetaxel synergized the anticancer effect induced by SC-60 through the SHP-1/STAT3 pathway in TNBC cells. Importantly, SC-60 also displayed a significant antitumor effect in an MDA-MB-468 xenograft model by modulating the SHP-1/STAT3 axis, indicating the anticancer potential of SC-60 in TNBC treatment. Targeting SHP-1/p-STAT3 and the potential combination of SHP-1 agonist with chemotherapeutic docetaxel is a feasible therapeutic strategy for TNBC. © 2017 The Authors. Published by FEBS Press and John Wiley & Sons Ltd.

  2. Polyphenolic Extract of Euphorbia supina Attenuates Manganese-Induced Neurotoxicity by Enhancing Antioxidant Activity through Regulation of ER Stress and ER Stress-Mediated Apoptosis

    Directory of Open Access Journals (Sweden)

    Entaz Bahar

    2017-01-01

    Full Text Available Manganese (Mn is an important trace element present in human body, which acts as an enzyme co-factor or activator in various metabolic reactions. While essential in trace amounts, excess levels of Mn in human brain can produce neurotoxicity, including idiopathic Parkinson’s disease (PD-like extrapyramidal manganism symptoms. This study aimed to investigate the protective role of polyphenolic extract of Euphorbia supina (PPEES on Mn-induced neurotoxicity and the underlying mechanism in human neuroblastoma SKNMC cells and Sprague-Dawley (SD male rat brain. PPEES possessed significant amount of total phenolic and flavonoid contents. PPEES also showed significant antioxidant activity in 1,1-diphenyl-2-picrylhydrazyl (DPPH radical scavenging and reducing power capacity (RPC assays. Our results showed that Mn treatment significantly reduced cell viability and increased lactate dehydrogenase (LDH level, which was attenuated by PPEES pretreatment at 100 and 200 µg/mL. Additionally, PPEES pretreatment markedly attenuated Mn-induced antioxidant status alteration by resolving the ROS, MDA and GSH levels and SOD and CAT activities. PPEES pretreatment also significantly attenuated Mn-induced mitochondrial membrane potential (ΔΨm and apoptosis. Meanwhile, PPEES pretreatment significantly reversed the Mn-induced alteration in the GRP78, GADD34, XBP-1, CHOP, Bcl-2, Bax and caspase-3 activities. Furthermore, administration of PPEES (100 and 200 mg/kg to Mn exposed rats showed improvement of histopathological alteration in comparison to Mn-treated rats. Moreover, administration of PPEES to Mn exposed rats showed significant reduction of 8-OHdG and Bax immunoreactivity. The results suggest that PPEES treatment reduces Mn-induced oxidative stress and neuronal cell loss in SKNMC cells and in the rat brain. Therefore, PPEES may be considered as potential treat-ment in Mn-intoxicated patients.

  3. miR-19b enhances proliferation and apoptosis resistance via the EGFR signaling pathway by targeting PP2A and BIM in non-small cell lung cancer.

    Science.gov (United States)

    Baumgartner, Ulrich; Berger, Fabienne; Hashemi Gheinani, Ali; Burgener, Sabrina Sofia; Monastyrskaya, Katia; Vassella, Erik

    2018-02-19

    Epidermal growth factor receptor (EGFR) mutations enable constitutive active downstream signaling of PI3K/AKT, KRAS/ERK and JAK/STAT pathways, and promote tumor progression by inducing uncontrolled proliferation, evasion of apoptosis and migration of non-small cell lung cancer (NSCLC). In addition, such EGFR mutations increase the susceptibility of patients with NSCLC to tyrosine kinase inhibitor (TKI) therapy, but treated patients will invariably relapse with resistant disease. A global understanding of underlying molecular mechanisms of EGFR signaling may improve the management of NSCLC patients. microarray analysis was performed to identify PI3K/AKT-regulated miRNAs. Phosphoproteomic analysis and cell based assays were performed using NSCLC cell lines lentivirally transduced with anti-miR or miR overexpressing constructs. Here, we show that 17 miRNAs including members of the miR-17~ 92 cluster are dysregulated following PI3K/AKT inhibition of EGFR mutant NSCLC cells. Bioinformatics analysis revealed that dysregulated miRNAs act in a concerted manner to enhance the activity of the EGFR signaling pathway. These findings were closely mirrored by attenuation of miR-17~ 92 family member miR-19b in NSCLC cell lines which resulted in reduced phosphorylation of ERK, AKT and STAT and effector proteins in EGFR mutant NSCLC cells. Consistent with this finding, cell cycle progression, clonogenic growth and migration were reduced and apoptosis was enhanced. Co-treatment of NSCLC cells with the tyrosine kinase inhibitor (TKI) gefitinib and anti-miR-19b construct reduced migration and clonogenic growth in a synergistic manner suggesting that EGFR and miR-19b act together to control oncogenic processes. Serine/threonine phosphatase PP2A subunit PPP2R5E and BCL2L11 encoding BIM were identified as major targets of miR-19b by target validation assays. Consistent with this finding, PP2A activity was strongly enhanced in NSCLC transduced with anti-miR-19b construct, but not in

  4. Hyperthermia-induced apoptosis

    NARCIS (Netherlands)

    Nijhuis, E.H.A.

    2008-01-01

    This thesis describes a number of studies that investigated several aspects of heat-induced apoptosis in human lymphoid malignancies. Cells harbour both pro- and anti-apoptotic proteins and the balance between these proteins determines whether a cell is susceptible to undergo apoptosis. In this

  5. Ubiquitination in apoptosis signaling

    NARCIS (Netherlands)

    van de Kooij, L.W.

    2014-01-01

    The work described in this thesis focuses on ubiquitination and protein degradation, with an emphasis on how these processes regulate apoptosis signaling. More specifically, our aims were: 1. To increase the understanding of ubiquitin-mediated regulation of apoptosis signaling. 2. To identify the E3

  6. Apoptosis of neutrophils

    NARCIS (Netherlands)

    Maianski, N. A.; Maianski, A. N.; Kuijpers, T. W.; Roos, D.

    2004-01-01

    Regulation of the neutrophil life span by apoptosis provides a fine balance between their function as effector cells of host defense and a safe turnover of these potentially harmful cells. Alterations of neutrophil apoptosis are associated with a number of diseases. As do other cell types,

  7. Transferrin-functionalized nanographene oxide for delivery of platinum complexes to enhance cancer-cell selectivity and apoptosis-inducing efficacy

    Science.gov (United States)

    Zhu, Hai; Zhou, Binwei; Chan, Leung; Du, Yanxin; Chen, Tianfeng

    2017-01-01

    Rational design and construction of delivery nanosystems for anticancer metal complexes is a crucial strategy to improve solubility under physiological conditions and permeability and retention behavior in tumor cells. Therefore, in this study, we designed and synthesize a transferrin (Tf)-conjugated nanographene oxide (NGO) nanosystem as a cancer-targeted nanocarrier of Pt complexes (Tf-NGO@Pt). This nanodelivery system exhibited good solubility under physiological conditions. Moreover, Tf-NGO@Pt showed higher anticancer efficacy against MCF human breast cancer cells than the free Pt complex, and effectively inhibited cancer-cell migration and invasion, with involvement of reactive oxygen species overproduction. In addition, nanolization also enhanced the penetration ability and inhibitory effect of the Pt complex toward MCF7 breast cancer-cell tumor spheroids. The enhancement of anticancer efficacy was positively correlated with increased cellular uptake and cellular drug retention. This study provides a new strategy to facilitate the future application of metal complexes in cancer therapy. PMID:28761342

  8. Hyperthermia: an effective strategy to induce apoptosis in cancer cells.

    Science.gov (United States)

    Ahmed, Kanwal; Tabuchi, Yoshiaki; Kondo, Takashi

    2015-11-01

    Heat has been used as a medicinal and healing modality throughout human history. The combination of hyperthermia (HT) with radiation and anticancer agents has been used clinically and has shown positive results to a certain extent. However, the clinical results of HT treatment alone have been only partially satisfactory. Cell death following HT treatment is a function of both temperature and treatment duration. HT induces cancer cell death through apoptosis; the degree of apoptosis and the apoptotic pathway vary in different cancer cell types. HT-induced reactive oxygen species production are responsible for apoptosis in various cell types. However, the underlying mechanism of signal transduction and the genes related to this process still need to be elucidated. In this review, we summarize the molecular mechanism of apoptosis induced by HT, enhancement of heat-induced apoptosis, and the genetic network involved in HT-induced apoptosis.

  9. Norcantharidin (NCTD) induces mitochondria mediated apoptosis in ...

    African Journals Online (AJOL)

    Administrator

    2011-06-15

    60 by inducing apoptosis through the mitochondria-dependent pathway. Eur. J. Pharmacol. 645: 14-22. Zhang C, Peng Y, Wang F, Tan X, Liu N, Fan S (2010). A synthetic cantharidin analog for the enhancement of doxorubicin ...

  10. Apoptosis and plastic surgery.

    Science.gov (United States)

    Gastman, Brian R; Futrell, J William; Manders, Ernest K

    2003-04-01

    Apoptosis, or programmed cell death, is a phenomenon that is integral to development and cellular homeostasis. In the last decade, many of the essential molecules and pathways that control this phenomenon have been elucidated. Because apoptosis is involved in almost all physiologic and pathologic processes, the understanding of its regulation has significant clinical ramifications. This article reviews the basic understanding of programmed cell death in terms of the effector molecules and pathways. Areas of interest to plastic surgeons are reviewed as they pertain to apoptosis. These areas include allotransplantation, craniofacial and limb development, flap survival, wound healing, stem cell science, and physiologic aging. These topics have not yet been studied extensively in the context of cell death. In this review article, other related and more comprehensively studied scientific areas are used to extrapolate their relevance to apoptosis. Apoptosis is an increasingly better understood process. With the knowledge of how programmed cell death is controlled, combined with the improved ability to effectively perform genetic manipulation and to design specific chemical approaches, apoptosis is gaining clinical relevance. In the next few years, practical clinical breakthroughs will help the medical community to understand the phenomenon of apoptosis and how it relates to the needs of patients.

  11. Caspases: An apoptosis mediator

    Directory of Open Access Journals (Sweden)

    Tapan Kumar Palai

    2015-03-01

    Full Text Available The process of programmed cell death, or apoptosis, is generally characterized by distinct morphological characteristics and energy - dependent biochemical mechanisms. Apoptosis is a widely conserved phenomenon helping many processes, including normal cell turnover, proper development and functioning of the immune system, hormone dependent atrophy etc. Inappropriate apoptosis (either low level or high level leads to many developmental abnormalities like, neurodegenerative diseases, ischemic damage, autoimmune disorders and many types of cancer. To use cells for therapeutic purposes through generating cell lines, it is critical to study the cell cycle machinery and signalling pathways that controls cell death and apoptosis. Apoptotic pathways provide a fundamental protective mechanism that decreases cellular sensitivity to damaging events and allow proper developmental process in multi-cellular organisms. Major mediator of apoptosis is a family of proteins known as caspases. There are mainly fourteen types of caspases but out of them only ten caspasese have got essential role in controlling the process of apoptosis. These ten caspases have been categorized into either initiator caspases (caspase 2, 8, 9, 10 or executioner caspases (caspase 3, 6, 7. Although various types of caspases have been identified so far, the exact mechanisms of action of these groups of proteins is still to be fully understood. The aim of this review is to provide a detail overview of role of different caspases in regulating the process of apoptosis.

  12. Reaper-Induced Apoptosis

    National Research Council Canada - National Science Library

    Perry, Jennifer

    2005-01-01

    Reaper is a central regulator of apoptosis in the fly, Drosophila melanogaster. At the start of this proposal our laboratory identified what was believed to be a pro-apoptotic human homolog of Reaper...

  13. Apoptosis in Pneumovirus Infection

    Directory of Open Access Journals (Sweden)

    Reinout A. Bem

    2013-01-01

    Full Text Available Pneumovirus infections cause a wide spectrum of respiratory disease in humans and animals. The airway epithelium is the major site of pneumovirus replication. Apoptosis or regulated cell death, may contribute to the host anti-viral response by limiting viral replication. However, apoptosis of lung epithelial cells may also exacerbate lung injury, depending on the extent, the timing and specific location in the lungs. Differential apoptotic responses of epithelial cells versus innate immune cells (e.g., neutrophils, macrophages during pneumovirus infection can further contribute to the complex and delicate balance between host defense and disease pathogenesis. The purpose of this manuscript is to give an overview of the role of apoptosis in pneumovirus infection. We will examine clinical and experimental data concerning the various pro-apoptotic stimuli and the roles of apoptotic epithelial and innate immune cells during pneumovirus disease. Finally, we will discuss potential therapeutic interventions targeting apoptosis in the lungs.

  14. Apoptosis Signal-Regulating Kinase 1 Is Involved in Brain-Derived Neurotrophic Factor (BDNF)-Enhanced Cell Motility and Matrix Metalloproteinase 1 Expression in Human Chondrosarcoma Cells

    Science.gov (United States)

    Lin, Chih-Yang; Chang, Sunny Li-Yun; Fong, Yi-Chin; Hsu, Chin-Jung; Tang, Chih-Hsin

    2013-01-01

    Chondrosarcoma is the primary malignancy of bone that is characterized by a potent capacity to invade locally and cause distant metastasis, and is therefore associated with poor prognoses. Chondrosarcoma further shows a predilection for metastasis to the lungs. The brain-derived neurotrophic factor (BDNF) is a small molecule in the neurotrophin family of growth factors that is associated with the disease status and outcome of cancers. However, the effect of BDNF on cell motility in human chondrosarcoma cells is mostly unknown. Here, we found that human chondrosarcoma cell lines had significantly higher cell motility and BDNF expression compared to normal chondrocytes. We also found that BDNF increased cell motility and expression of matrix metalloproteinase-1 (MMP-1) in human chondrosarcoma cells. BDNF-mediated cell motility and MMP-1 up-regulation were attenuated by Trk inhibitor (K252a), ASK1 inhibitor (thioredoxin), JNK inhibitor (SP600125), and p38 inhibitor (SB203580). Furthermore, BDNF also promoted Sp1 activation. Our results indicate that BDNF enhances the migration and invasion activity of chondrosarcoma cells by increasing MMP-1 expression through a signal transduction pathway that involves the TrkB receptor, ASK1, JNK/p38, and Sp1. BDNF thus represents a promising new target for treating chondrosarcoma metastasis. PMID:23892595

  15. Jaeumganghwa-Tang Induces Apoptosis via the Mitochondrial Pathway and Lactobacillus Fermentation Enhances Its Anti-Cancer Activity in HT1080 Human Fibrosarcoma Cells

    Science.gov (United States)

    Kim, Aeyung; Im, Minju; Hwang, Youn-Hwan; Yang, Hye Jin; Ma, Jin Yeul

    2015-01-01

    Jaeumganghwa-tang (JGT, Zi-yin-jiang-huo-tang in Chinese and Jiin-koka-to in Japanese) is an oriental herbal formula that has long been used as a traditional medicine to treat respiratory and kidney diseases. Recent studies revealed that JGT exhibited potent inhibitory effects on allergies, inflammation, pain, convulsions, and prostate hyperplasia. Several constituent herbs in JGT induce apoptotic cancer cell death. However, the anti-cancer activity of JGT has not been examined. In this study, we investigated the anti-cancer effects of JGT using highly tumorigenic HT1080 human fibrosarcoma cells and elucidated the underlying mechanisms. In addition, we examined whether the Lactobacillus fermentation of JGT enhanced its anti-cancer activity using an in vivo xenograft model because fermentation of herbal extracts is thought to strengthen their therapeutic effects. Data revealed that JGT suppressed the growth of cancer cells efficiently by stimulating G1 cell cycle arrest and then inducing apoptotic cell death by causing mitochondrial damage and activating caspases. The phosphorylation of p38 and ERK also played a role in JGT-induced cell death. In vitro experiments demonstrated that JGT fermented with Lactobacillus acidophilus, designated fJGT162, elicited similar patterns of cell death as did non-fermented JGT. Meanwhile, the daily oral administration of 120 mg/kg fJGT162 to HT1080-bearing BALB/c nude mice suppressed tumor growth dramatically (up to 90%) compared with saline treatment, whereas the administration of non-fermented JGT suppressed tumor growth by ~70%. Collectively, these results suggest that JGT and fJGT162 are safe and useful complementary and alternative anti-cancer herbal therapies, and that Lactobacillus fermentation improves the in vivo anti-cancer efficacy of JGT significantly. PMID:26020238

  16. Apoptosis and cell cycle

    Directory of Open Access Journals (Sweden)

    Petrović Marija

    2014-01-01

    Full Text Available Apoptosis, a form of programmed cell death, is used to eliminate individual cells surrounded by normal cell population. It is a controlled way of cell death in which the cell actively participates by conducting precise, gene-regulated program of self-destruction, that is, cell 'suicide.' Active synthesis of macromolecules is necessary during this process. Death of individual cells is necessary to maintain a balance in living systems, so the process of apoptosis is continuously present in the body, which allows normal development, tissue homeostasis, and many other physiological processes. The molecular mechanisms that regulate apoptosis are functionally linked to other cellular mechanisms, such as control of the cell cycle, cell proliferation and differentiation, genomic stability and cellular metabolism. Damage to the DNA molecule, caused both spontaneously and under the influence of various chemical and physical agents, leads to the cell cycle arrest and activation of mechanisms that repair the damage. Depending on the type and extent of the damage, the cell either continues progression through the cell cycle, or activates the mechanisms that lead to apoptosis. Disturbances in the regulation of apoptosis and cell cycle present the molecular and biological basis of many diseases. Because of the importance of these processes during the development and progression of tumors, their use as biological markers is one of the main strategies in the formation of therapeutic approaches for the treatment of cancer.

  17. Spaceflight Associated Apoptosis

    Science.gov (United States)

    Ichiki, Albert T.; Gibson, Linda A.; Allebban, Zuhair

    1996-01-01

    Lymphoid tissues have been shown to atrophy in rats flown on Russian spaceflights. Histological examination indicated evidence for cell degradation. Lymphoid tissues from rats flown on Spacelab Life Sciences-2 mission were analyzed for apoptosis by evidence of fragmented lymphocytes, which could be engulfed by macrophages, or DNA strand breaks using the terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) assay. Apoptosis was not detected in the thymus and spleen collected inflight or from the synchronous ground rats but was detected in the thymus, spleen and inguinal lymph node of the flight animals on recovery. These results indicate that the apoptosis observed in the lymphatic tissues of the rats on recovery could have been induced by the gravitational stress of reentry, corroborating the findings from the early space-flight observations.

  18. Regulation of Neutrophil Survival/Apoptosis by Mcl-1

    Directory of Open Access Journals (Sweden)

    Eric Milot

    2011-01-01

    Full Text Available Neutrophil granulocytes have the shortest lifespan among leukocytes in the circulation and die via apoptosis. At sites of infection or tissue injury, prolongation of neutrophil lifespan is critical for effective host defense. Apoptosis of inflammatory neutrophils and their clearance are critical control points for termination of the inflammatory response. Evasion of neutrophil apoptosis aggravates local injury and leads to persistent tissue damage. The short-lived prosurvival Bcl-2 family protein, Mcl-1 (myeloid cell leukemia-1, is instrumental in controlling apoptosis and consequently neutrophil lifespan in response to rapidly changing environmental cues during inflammation. This paper will focus on multiple levels of control of Mcl-1 expression and function and will discuss targeting Mcl-1 as a potential therapeutic strategy to enhance the resolution of inflammation through accelerating neutrophil apoptosis.

  19. LYMPHOCYTE APOPTOSIS IN PSORIASIS

    Directory of Open Access Journals (Sweden)

    О. M. Kapuler

    2006-01-01

    Full Text Available Abstract. Forty-two patients with progressive vulgar psoriasis (PASI = 19.7 ± 1.5 and 40 healthy volunteers were under investigation. Psoriatic patients were characterized by increased number of CD4+ CD95+ peripheral blood T lymphocytes, which correlates with clinical psoriatic score, and by increased levels of soluble Fas (sFas in serum, as compared to controls (resp., 1868.1 ± 186.8 pg/ml vs. 1281.4 ± 142.5 pg/ml, PLSD = 0.019. The levels of spontaneous lymphocyte apoptosis and anti-Fas (Mab-induced apoptosis in psoriatic patients did not differ from the controls. However, apoptosis induced by “oxidative stress” (50 M Н202, 4 hrs was depressed in the patients. Moreover, a simultaneous assessment of cell cycle structure (metachromatic staining with Acridine Orange, apoptosis and Fas receptor expression (AnnV-FITC/antiFas mAbs-PE staining following a short-term mitogenic stimulation (PHA-P, 5 µg/ml, 24 hrs were performed. We found no marked differences in mitogenic reactivity, activation-induced apoptosis, and activation-induced Fas receptor expression when studying lymphocytes from healthy donors and psoriatic patients. However, PHA-activated lymphocytes from psoriatic patients displayed a significantly decreased ratio of AnnV+CD95+ to the total AnnV+ subpopulation, thus suggesting a decreased role of Fas-dependent mechanisms of apoptosis during the cell activation. The data obtained confirm a view, that an abnormal lymphocyte “apoptotic reactivity”, which plays a crucial role in the mechanisms of autoimmunity, may also of importance in the pathogenesis of psoriasis.

  20. Enhanced

    Directory of Open Access Journals (Sweden)

    Martin I. Bayala

    2014-06-01

    Full Text Available Land Surface Temperature (LST is a key parameter in the energy balance model. However, the spatial resolution of the retrieved LST from sensors with high temporal resolution is not accurate enough to be used in local-scale studies. To explore the LST–Normalised Difference Vegetation Index relationship potential and obtain thermal images with high spatial resolution, six enhanced image sharpening techniques were assessed: the disaggregation procedure for radiometric surface temperatures (TsHARP, the Dry Edge Quadratic Function, the Difference of Edges (Ts∗DL and three models supported by the relationship of surface temperature and water stress of vegetation (Normalised Difference Water Index, Normalised Difference Infrared Index and Soil wetness index. Energy Balance Station data and in situ measurements were used to validate the enhanced LST images over a mixed agricultural landscape in the sub-humid Pampean Region of Argentina (PRA, during 2006–2010. Landsat Thematic Mapper (TM and Moderate Resolution Imaging Spectroradiometer (EOS-MODIS thermal datasets were assessed for different spatial resolutions (e.g., 960, 720 and 240 m and the performances were compared with global and local TsHARP procedures. Results suggest that the Ts∗DL technique is the most adequate for simulating LST to high spatial resolution over the heterogeneous landscape of a sub-humid region, showing an average root mean square error of less than 1 K.

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

    Science.gov (United States)

    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. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. APOPTOSIS AND CHRONIC CARDIAC INSUFFICIENCY

    Directory of Open Access Journals (Sweden)

    A.G. Gasanov

    2009-01-01

    Full Text Available Research into molecular apoptosis mechanisms in patients with cardio-vascular diseases is one of the pressing issues in modern medicine. Many mechanisms of this phenomenon still remain unexamined, the role of inductors and regulators in cardiomyocyte apoptosis has not yet been fully explained. This review summarizes research data that analyze the role that various groups of cell death inductors and regulators, such as FasL, Fas-R and mitochondrial apoptosis factors. Influence of the Bcl-2 protein family as apoptosis regulators is described. Developments in programmed cell death are reviewed.Key words: apoptosis, cell death mechanisms, mitochondria, cardiamyocytes.

  3. A novel method for detection of apoptosis

    Energy Technology Data Exchange (ETDEWEB)

    Zagariya, Alexander M., E-mail: zagariya@uic.edu

    2012-04-15

    There are two different Angiotensin II (ANG II) peptides in nature: Human type (ANG II) and Bovine type (ANG II*). These eight amino acid peptides differ only at position 5 where Valine is replaced by Isoleucine in the Bovine type. They are present in all species studied so far. These amino acids are different by only one atom of carbon. This difference is so small, that it will allow any of ANG II, Bovine or Human antibodies to interact with all species and create a universal method for apoptosis detection. ANG II concentrations are found at substantially higher levels in apoptotic, compared to non-apoptotic, tissues. ANG II accumulation can lead to DNA damage, mutations, carcinogenesis and cell death. We demonstrate that Bovine antiserum can be used for universal detection of apoptosis. In 2010, the worldwide market for apoptosis detection reached the $20 billion mark and significantly increases each year. Most commercially available methods are related to Annexin V and TUNNEL. Our new method based on ANG II is more widely known to physicians and scientists compared to previously used methods. Our approach offers a novel alternative for assessing apoptosis activity with enhanced sensitivity, at a lower cost and ease of use.

  4. Fullerene and apoptosis

    Directory of Open Access Journals (Sweden)

    M. A. Orlova

    2013-01-01

    Full Text Available Fullerene derivatives superfamily attracts a serious attention as antiviral and anticancer agents and drug delivery carriers as well. A large number of such fullerene С60 derivatives obtained to date. However, there is an obvious deficit of information about causes and mechanisms of immediately and long-term consequences of their effects in vivo which is a true obstacle on the way leading to practical medical use of them. First, this concerns their impact on the proliferation, apoptosis and necrosis regulation. Fullerene nanoparticle functionalization type, their sizes and surface nanopathology are of great importance to further promoting of either cytoprotective or cytotoxic effects. This lecture provides modern concept analysis regarding fullerenes effects on apoptosis pathway in normal and tumor cells.

  5. Cl- channels in apoptosis

    DEFF Research Database (Denmark)

    Wanitchakool, Podchanart; Ousingsawat, Jiraporn; Sirianant, Lalida

    2016-01-01

    A remarkable feature of apoptosis is the initial massive cell shrinkage, which requires opening of ion channels to allow release of K(+), Cl(-), and organic osmolytes to drive osmotic water movement and cell shrinkage. This article focuses on the role of the Cl(-) channels LRRC8, TMEM16/anoctamin......, and cystic fibrosis transmembrane conductance regulator (CFTR) in cellular apoptosis. LRRC8A-E has been identified as a volume-regulated anion channel expressed in many cell types. It was shown to be required for regulatory and apoptotic volume decrease (RVD, AVD) in cultured cell lines. Its presence also......(-) channels or as regulators of other apoptotic Cl(-) channels, such as LRRC8. CFTR has been known for its proapoptotic effects for some time, and this effect may be based on glutathione release from the cell and increase in cytosolic reactive oxygen species (ROS). Although we find that CFTR is activated...

  6. Glycolaldehyde induces endoplasmic reticulum stress and apoptosis in Schwann cells

    Directory of Open Access Journals (Sweden)

    Keisuke Sato

    2015-01-01

    Full Text Available Schwann cell injury is caused by diabetic neuropathy. The apoptosis of Schwann cells plays a pivotal role in diabetic nerve dysfunction. Glycolaldehyde is a precursor of advanced glycation end products that contribute to the pathogenesis of diabetic neuropathy. In this study, we examined whether glycolaldehyde induces endoplasmic reticulum (ER stress and apoptosis in rat Schwann cells. Schwann cells treated with 500 μM glycolaldehyde showed morphological changes characteristic of apoptosis. Glycolaldehyde activated apoptotic signals, such as caspase-3 and caspase-8. Furthermore, it induced ER stress response involving RNA-dependent protein kinase-like ER kinase (PERK, inositol-requiring ER-to-nucleus signal kinase 1α (IRE1α, and eukaryotic initiation factor 2α (eIF2α. In addition, glycolaldehyde activated CCAAT/enhancer-binding homologous protein (CHOP, an ER stress response factor crucial to executing apoptosis. Knockdown of nuclear factor E2-related factor 2 (Nrf2, which is involved in the promotion of cell survival following ER stress, enhanced glycolaldehyde-induced cytotoxicity, indicating that Nrf2 plays a protective role in the cytotoxicity caused by glycolaldehyde. Taken together, these findings indicate that glycolaldehyde is capable of inducing apoptosis and ER stress in Schwann cells. The ER stress induced by glycolaldehyde may trigger the glycolaldehyde-induced apoptosis in Schwann cells. This study demonstrated for the first time that glycolaldehyde induced ER stress.

  7. Apoptosis and DNA Methylation

    Directory of Open Access Journals (Sweden)

    Richard R. Meehan

    2011-04-01

    Full Text Available Epigenetic mechanisms assist in maintaining gene expression patterns and cellular properties in developing and adult tissues. The molecular pathology of disease states frequently includes perturbation of DNA and histone methylation patterns, which can activate apoptotic pathways associated with maintenance of genome integrity. This perspective focuses on the pathways linking DNA methyltransferases and methyl-CpG binding proteins to apoptosis, and includes new bioinformatic analyses to characterize the evolutionary origin of two G/T mismatch-specific thymine DNA glycosylases, MBD4 and TDG.

  8. Delay of neutrophil apoptosis in acute coronary syndromes.

    Science.gov (United States)

    Garlichs, C D; Eskafi, S; Cicha, I; Schmeisser, A; Walzog, B; Raaz, D; Stumpf, C; Yilmaz, A; Bremer, J; Ludwig, J; Daniel, W G

    2004-05-01

    Apoptosis of polymorphonuclear neutrophils (PMN) is currently discussed as a key event in the control of inflammation. This study determined PMN apoptosis and its underlying mechanisms in controls (C), patients with stable (SAP) or unstable angina (UAP), and with acute myocardial infarction (AMI). Blood was drawn from 15 subjects of each C, SAP, UAP, and AMI. Apoptosis was measured by flow cytometry in isolated PMN (propidium iodide staining) and PMN from whole blood (CD16, FcgammaRIII). Serum cytokines were determined by enzyme-linked immunosorbent assay. Apoptosis of isolated PMN was delayed significantly in acute coronary syndromes (ACS) as compared with SAP or C (C, 51.2+/-12.6%; SAP, 44.9+/-13.6%; UAP, 28.4+/-10.1%; AMI, 20.3+/-8.5%; AMI or UAP vs. SAP or C, P<0.001). These results were confirmed by measurement of PMN apoptosis in cultured whole blood from patients and controls. Moreover, serum of patients with ACS markedly reduced apoptosis of PMN from healthy donors. Analysis of patients' sera revealed significantly elevated concentrations of tumor necrosis factor alpha, interferon-gamma (IFN-gamma), granulocyte macrophage-colony stimulating factor (GM-CSF), and interleukin (IL)-1beta in ACS (vs. C and SAP). IFN-gamma, GM-CSF, and IL-1beta significantly delayed PMN apoptosis in vitro. Furthermore, coincubation of PMN with adenosine 5'-diphosphate-activated platelets significantly inhibited PMN apoptosis as compared with coculture with unstimulated platelets. This study demonstrates a pronounced delay of PMN apoptosis in UAP and AMI, which may result from increased serum levels of IFN-gamma, GM-CSF, and IL-1beta and from enhanced platelet activation. Therapeutical modulation of these determinants of PMN lifespan may provide a new concept for the control of inflammation in ACS.

  9. Ceramide-Induced Apoptosis in Renal Tubular Cells: A Role of Mitochondria and Sphingosine-1-Phoshate

    Science.gov (United States)

    Ueda, Norishi

    2015-01-01

    Ceramide is synthesized upon stimuli, and induces apoptosis in renal tubular cells (RTCs). Sphingosine-1 phosphate (S1P) functions as a survival factor. Thus, the balance of ceramide/S1P determines ceramide-induced apoptosis. Mitochondria play a key role for ceramide-induced apoptosis by altered mitochondrial outer membrane permeability (MOMP). Ceramide enhances oligomerization of pro-apoptotic Bcl-2 family proteins, ceramide channel, and reduces anti-apoptotic Bcl-2 proteins in the MOM. This process alters MOMP, resulting in generation of reactive oxygen species (ROS), cytochrome C release into the cytosol, caspase activation, and apoptosis. Ceramide regulates apoptosis through mitogen-activated protein kinases (MAPKs)-dependent and -independent pathways. Conversely, MAPKs alter ceramide generation by regulating the enzymes involving ceramide metabolism, affecting ceramide-induced apoptosis. Crosstalk between Bcl-2 family proteins, ROS, and many signaling pathways regulates ceramide-induced apoptosis. Growth factors rescue ceramide-induced apoptosis by regulating the enzymes involving ceramide metabolism, S1P, and signaling pathways including MAPKs. This article reviews evidence supporting a role of ceramide for apoptosis and discusses a role of mitochondria, including MOMP, Bcl-2 family proteins, ROS, and signaling pathways, and crosstalk between these factors in the regulation of ceramide-induced apoptosis of RTCs. A balancing role between ceramide and S1P and the strategy for preventing ceramide-induced apoptosis by growth factors are also discussed. PMID:25751724

  10. Upregulation of heat shock protein 70 and the differential protein expression induced by tumor necrosis factor-alpha enhances migration and inhibits apoptosis of hepatocellular carcinoma cell HepG2

    OpenAIRE

    Huang, Bee-Piao; Lin, Chun-Shiang; Wang, Chau-Jong; Kao, Shao-Hsuan

    2017-01-01

    Tumor necrosis factor alpha (TNF?) plays diverse roles in liver damage and hepatocarcinogenesis with its multipotent bioactivity. However, the influence of TNF? on protein expression of hepatocellular carcinoma (HCC) is incompletely understood. Therefore, we aimed to investigate the differential protein expression of HCC in response to TNF? stimulus. We observed that HepG2 cell revealed a higher resistance to TNF?-induced apoptosis as compared to the non-tumorigenic hepatocyte THLE-2. By usin...

  11. Upregulation of heat shock protein 70 and the differential protein expression induced by tumor necrosis factor-alpha enhances migration and inhibits apoptosis of hepatocellular carcinoma cell HepG2.

    Science.gov (United States)

    Huang, Bee-Piao; Lin, Chun-Shiang; Wang, Chau-Jong; Kao, Shao-Hsuan

    2017-01-01

    Tumor necrosis factor alpha (TNFα) plays diverse roles in liver damage and hepatocarcinogenesis with its multipotent bioactivity. However, the influence of TNFα on protein expression of hepatocellular carcinoma (HCC) is incompletely understood. Therefore, we aimed to investigate the differential protein expression of HCC in response to TNFα stimulus. We observed that HepG2 cell revealed a higher resistance to TNFα-induced apoptosis as compared to the non-tumorigenic hepatocyte THLE-2. By using a label-free quantitative proteomic analysis, we found that 520 proteins were differentially expressed in the HepG2 cells exposed to TNFα, including 211 up-regulated and 309 down-regulated proteins. We further confirmed several proteins with significant expression change (TNFα/control ratio>2.0 or expressed proteins using Gene ontology and KEGG annotations, and the results implicated that TNFα might regulate ribosome, spliceosome, antigen processing and presentation, and energy metabolism in HepG2 cells. Moreover, we demonstrated that upregulation of heat shock protein 70 (HSP70) was involved in both the promoted migration and the inhibited apoptosis of HepG2 cells in response to TNFα. Collectively, these findings indicate that TNFα alters protein expression such as HSP70, which triggering specific molecular processes and signaling cascades that promote migration and inhibit apoptosis of HepG2 cells.

  12. Sorafenib induces cathepsin B-mediated apoptosis of bladder cancer cells by regulating the Akt/PTEN pathway. The Akt inhibitor, perifosine, enhances the sorafenib-induced cytotoxicity against bladder cancer cells

    Science.gov (United States)

    Amantini, Consuelo; Morelli, Maria Beatrice; Santoni, Matteo; Soriani, Alessandra; Cardinali, Claudio; Farfariello, Valerio; Eleuteri, Anna Maria; Bonfili, Laura; Mozzicafreddo, Matteo; Nabissi, Massimo; Cascinu, Stefano; Santoni, Giorgio

    2015-01-01

    Sorafenib, a tyrosine kinase inhibitor, has been demonstrated to exert anti-tumor effects. However, the molecular mechanisms underlying its effects on bladder cancer remain unknown. Here, we evaluated the mechanisms responsible for the sorafenib-induced anti-tumor effects on 5637 and T24 bladder cancer cells. We demonstrated that sorafenib reduces cell viability, stimulates lysosome permeabilization and induces apoptosis of bladder cancer cells. These effects are dependent by the activation of cathepsin B released from lysosomes. The sorafenib-increased cathepsin B activity induced the proteolysis of Bid into tBid that stimulates the intrinsic pathway of apoptosis characterized by mitochondrial membrane depolarization, oxygen radical generation and cytochrome c release. Moreover, we found that cathepsin B enzymatic activity, induced by sorafenib, is dependent on its dephosphorylation via PTEN activation and Akt inactivation. Pretreatment with orthovanadate rescued bladder cancer cells from apoptosis. In addition, the Akt inhibitor perifosine increased the sensitivity of bladder cancer cells to sorafenib-induced cytotoxicity. Overall, our results show that apoptotic cell death induced by sorafenib in bladder cancer cells is dependent on cathepsin B activity and involved PTEN and Akt signaling pathways. The Akt inhibitor perifosine increased the cytotoxic effects of sorafenib in bladder cancer cells. PMID:26097873

  13. Reassessing apoptosis in plants.

    Science.gov (United States)

    Dickman, Martin; Williams, Brett; Li, Yurong; de Figueiredo, Paul; Wolpert, Thomas

    2017-10-01

    Cell death can be driven by a genetically programmed signalling pathway known as programmed cell death (PCD). In plants, PCD occurs during development as well as in response to environmental and biotic stimuli. Our understanding of PCD regulation in plants has advanced significantly over the past two decades; however, the molecular machinery responsible for driving the system remains elusive. Thus, whether conserved PCD regulatory mechanisms include plant apoptosis remains enigmatic. Animal apoptotic regulators, including Bcl-2 family members, have not been identified in plants but expression of such regulators can trigger or suppress plant PCD. Moreover, plants exhibit nearly all of the biochemical and morphological features of apoptosis. One difference between plant and animal PCD is the absence of phagocytosis in plants. Evidence is emerging that the vacuole may be key to removal of unwanted plant cells, and may carry out functions that are analogous to animal phagocytosis. Here, we provide context for the argument that apoptotic-like cell death occurs in plants.

  14. Apoptosis Resistance in Endometriosis

    Directory of Open Access Journals (Sweden)

    Liselotte Mettler

    2011-08-01

    Full Text Available Introduction: In a cytological analysis of endometriotic lesions neither granulocytes nor cytotoxic T-cells appear in an appreciable number. Based on this observation we aimed to know, whether programmed cell death plays an essential role in the destruction of dystopic endometrium. Disturbances of the physiological mechanisms of apoptosis, a persistence of endometrial tissue could explain the disease. Another aspect of this consideration is the proliferation competence of the dystopic mucous membrane. Methods: Endometriotic lesions of 15 patients were examined through a combined measurement of apoptosis activity with the TUNEL technique (terminal deoxyribosyltransferase mediated dUTP Nick End Labeling and the proliferation activity (with the help of the Ki-67-Antigens using the monoclonal antibody Ki-S5. Results: Twelve out of 15 women studied showed a positive apoptotic activity of 3-47% with a proliferation activity of 2-25% of epithelial cells. Therefore we concluded that the persistence of dystopic endometrium requires proliferative epithelial cells from middle to lower endometrial layers. Conclusion: A dystopia misalignment of the epithelia of the upper layers of the functionalism can be rapidly eliminated by apoptotic procedures.

  15. Nucleolus and apoptosis.

    Science.gov (United States)

    Horký, M; Kotala, V; Anton, M; Wesierska-Gadek, J

    2002-11-01

    The nucleolus represents a highly dynamic nuclear compartment of the interphase nucleus. It plays a key role in ribosome biogenesis. The number of nucleoli, their size, and their activity increase in exponentially growing cells; therefore these parameters reflect the proliferating activity of the cells. A variety of staining techniques have been employed to vizualize nucleolar changes in malignant cells. Staining of so-called nucleolar organizer regions (NORs), based upon a strong avidity of nucleolar proteins to bind silver ions, represents the technique most frequently used by pathologists. Nucleolar changes and pleomorphism associated with overt proliferation of tumor cells have also been documented by immunohistochemical and ultrastructural studies. Contrary to cell proliferation, cytostatics-induced changes of nucleolar phenotype in malignant cells point to a potential role of nucleolar components in the execution of active cell death. Recent studies have provided direct clues that so-called death domains and other apoptosis-related proteins are accumulated in nucleoli upon induction of active cell death. It can be concluded that the plurifunctionality of nucleoli regarding cell proliferation and apoptosis could open new vistas toward understanding dysregulation in malignant cells.

  16. Antioxidant micronutrients improve intrinsic and UV-induced apoptosis of human lymphocytes particularly in elderly people

    NARCIS (Netherlands)

    Ma, A.G.; Ge, S.; Zhang, M.; Shi, X.X.; Schouten, E.G.; Kok, F.J.; Sun, Y.Y.; Han, X.X.

    2011-01-01

    Objective: Aging and oxidative stress may lead to enhanced cellular damage and programmed cell death. to study the association of intrinsic apoptosis with age and the effect of antioxidant supplementation on intrinsic and UV-induced apoptosis in children, young and elderly people. Methods: The study

  17. Drug-induced reactivation of apoptosis abrogates HIV-1 infection.

    Directory of Open Access Journals (Sweden)

    Hartmut M Hanauske-Abel

    Full Text Available HIV-1 blocks apoptosis, programmed cell death, an innate defense of cells against viral invasion. However, apoptosis can be selectively reactivated in HIV-infected cells by chemical agents that interfere with HIV-1 gene expression. We studied two globally used medicines, the topical antifungal ciclopirox and the iron chelator deferiprone, for their effect on apoptosis in HIV-infected H9 cells and in peripheral blood mononuclear cells infected with clinical HIV-1 isolates. Both medicines activated apoptosis preferentially in HIV-infected cells, suggesting that the drugs mediate escape from the viral suppression of defensive apoptosis. In infected H9 cells, ciclopirox and deferiprone enhanced mitochondrial membrane depolarization, initiating the intrinsic pathway of apoptosis to execution, as evidenced by caspase-3 activation, poly(ADP-ribose polymerase proteolysis, DNA degradation, and apoptotic cell morphology. In isolate-infected peripheral blood mononuclear cells, ciclopirox collapsed HIV-1 production to the limit of viral protein and RNA detection. Despite prolonged monotherapy, ciclopirox did not elicit breakthrough. No viral re-emergence was observed even 12 weeks after drug cessation, suggesting elimination of the proviral reservoir. Tests in mice predictive for cytotoxicity to human epithelia did not detect tissue damage or activation of apoptosis at a ciclopirox concentration that exceeded by orders of magnitude the concentration causing death of infected cells. We infer that ciclopirox and deferiprone act via therapeutic reclamation of apoptotic proficiency (TRAP in HIV-infected cells and trigger their preferential elimination. Perturbations in viral protein expression suggest that the antiretroviral activity of both drugs stems from their ability to inhibit hydroxylation of cellular proteins essential for apoptosis and for viral infection, exemplified by eIF5A. Our findings identify ciclopirox and deferiprone as prototypes of

  18. Accelerated apoptosis of neutrophils in familial Mediterranean fever

    DEFF Research Database (Denmark)

    Manukyan, Gayane; Aminov, Rustam; Hakobyan, Gagik

    2015-01-01

    not revealed any conventional mechanisms contributing to the enhanced apoptotic rate of neutrophils in FMF. Although the exact molecular mechanisms of accelerated neutrophil apoptosis in FMF remain unknown, it may provide a protection against excessive inflammation and tissue damage due to a massive...

  19. Knockdown of HIF-1α and IL-8 induced apoptosis of hepatocellular carcinoma triggers apoptosis of vascular endothelial cells.

    Science.gov (United States)

    Choi, Sung Hoon; Park, Jun Yong; Kang, Wonseok; Kim, Seung Up; Kim, Do Young; Ahn, Sang Hoon; Ro, Simon Wonsang; Han, Kwang-Hyub

    2016-01-01

    A local hypoxic microenvironment is one of the most important characteristics of solid tumors. Hypoxia inducible factor-1α (HIF-1α) and Interleukin-8 (IL-8) activate tumor survival from hypoxic-induced apoptosis in each pathway. This study aimed to evaluate whether knockdown of HIF-1α and IL-8 induced apoptosis of the hepatocellular carcinoma (HCC) and endothelial cell lines. HCC cell lines were infected with adenovirus-expressing shRNA for HIF-1α and IL-8 and maintained under hypoxic conditions (1% O2, 24 h). The expression levels of HIF-1α and both apoptotic and growth factors were examined by real-time quantitative PCR and western blot. We also investigated apoptosis by TUNEL assay (FACS and Immunofluorescence) and measured the concentration of cytochrome C. Inhibition of HIF-1α and IL-8 up-regulated the expression of apoptotic factors while downregulating anti-apoptotic factors simultaneously. Knockdown of HIF-1α and IL-8 increased the concentration of cytochrome C and enhanced DNA fragmentation in HCC cell lines. Moreover, culture supernatant collected from the knockdown of HIF-1α and IL-8 in HCC cell lines induced apoptosis in human umbilical vein endothelial cells under hypoxia, and the expression of variable apoptotic ligand increased from HCC cell lines, time-dependently. These data suggest that adenovirus-mediated knockdown of HIF-1α and IL-8 induced apoptosis in HCC cells and triggered apoptosis of vascular endothelial cells.

  20. Hexavalent chromium induced oxidative stress and apoptosis in Pycnoporus sanguineus.

    Science.gov (United States)

    Feng, Mi; Yin, Hua; Peng, Hui; Liu, Zehua; Lu, Guining; Dang, Zhi

    2017-09-01

    White rot fungi have been proved to be a promising option for the removal of heavy metals, understanding their toxic response to heavy metals is conducive to developing and popularizing fungi-based remediation technologies so as to lessen the hazard of heavy metals. In this study, Cr(VI)-induced oxidative stress and apoptosis in Pycnoporus sanguineus, a species of white rot fungi were investigated. The results suggested that high level of Cr(VI) promoted the formation of ROS, including H2O2, O2(•-) and ·OH. With the increment of Cr(VI) concentration, the SOD and CAT activity along with GSH content increased within the first 24 h, but decreased afterward, companied with a significant enhancement of MDA content. Cr(VI)-induced oxidative damage further caused and aggravated apoptosis in P. sanguineus, especially at Cr(VI) concentrations above 20 mg/L. Cr(VI)-induced apoptosis was involved with mitochondrial dysfunction including mitochondrial depolarization, the enhancement of mitochondrial permeability and release of cytochrome c. The early and late apoptosis hallmarks, such as metacaspase activation, phosphatidylserine (PS) externalization, DNA fragmentation and the nuclear condensation and fragmentation were observed. Moreover, we also found disturbances of ion homeostasis, which was featured by K(+) effluxes and overload of cytoplasmic and mitochondrial Ca(2+).Based on these results, we suggest that Cr(VI) induced oxidative stress and apoptosis in white rot fungi, P. sanguineus. Copyright © 2017 Elsevier Ltd. All rights reserved.

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

    Directory of Open Access Journals (Sweden)

    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

  2. RIP-1/c-FLIPL Induce Hepatic Cancer Cell Apoptosis Through Regulating Tumor Necrosis Factor-Related Apoptosis-Inducing Ligand (TRAIL).

    Science.gov (United States)

    Sun, Jichun; Yu, Xiao; Wang, Changfa; Yu, Can; Li, Zhiqiang; Nie, Wanpin; Xu, Xundi; Miao, Xiongying; Jin, Xiaoxin

    2017-03-08

    BACKGROUND Almost all hepatic cancer cells have resistance to tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-induced apoptosis. c-FLIPL and RIP-1 are apoptotic negative regulatory factors. This study investigated the role of c-FLIPL and RIP-1 in hepatic cancer cell resistance to TRAIL-induced apoptosis. MATERIAL AND METHODS HepG2 cells were treated by TRAIL, RIP-1 siRNA, and/or BY11-7082. Cell viability was detected by MTT assay. Cell apoptosis was tested by flow cytometry. DISC component proteins, RIP-1, and p-p65 were measured by Western blot. Caspase-8 and caspase-3 were determined by spectrophotometry. RESULTS Single TRAIL treatment showed no significant impact on cell proliferation and apoptosis. HepG2 cells expressed high levels of RIP1 and c-FLIPL, while a high concentration of TRAIL upregulated RIP-1 and c-FLIPL expression but not DR4 and DR5. Single TRAIL treatment did not obviously activate caspase-8 and caspase-3. RIP-1 or c-FLIPL siRNA markedly induced cell apoptosis and enhanced caspase-8 and caspase-3 activities. Combined transfection obviously increased apoptotic cells. TRAIL markedly upregulated RIP-1 expression and enhanced p-p65 protein. Downregulating RIP-1 and/or BAY11-7082 significantly reduced NF-kB transcriptional activity, blocked cells in G0/G1 phase, weakened proliferation, elevated caspase-8 and caspase-3 activities, and promoted cell apoptosis. CONCLUSIONS TRAIL can enhance RIP1 and c-FLIPL expression in HepG2 cells. High expression of RIP1 and c-FLIPL is an important reason for TRAIL resistance. Downregulation of RIP1 and c-FLIPL can relieve caspase-8 suppression, activate caspase-3, and promote cell apoptosis. TRAIL mediates apoptosis resistance through upregulating RIP-1 expression, enhancing NF-kB transcriptional activity, and weakening caspase activity.

  3. Methylselenium and Prostate Cancer Apoptosis

    National Research Council Canada - National Science Library

    Lu, Junxuan

    2008-01-01

    The purpose of this research is to gain a better understanding of the biochemical pathways and molecular targets for the selective induction of apoptosis signaling and execution of prostate cancer (PCa...

  4. Methylselenium and Prostate Cancer Apoptosis

    National Research Council Canada - National Science Library

    Lu, Junxuan

    2006-01-01

    The purpose of this research is to gain a better understanding of the biochemical pathways and molecular targets for the selective induction of apoptosis signaling and execution of prostate cancer (PCa...

  5. Methylselenium and Prostate Cancer Apoptosis

    National Research Council Canada - National Science Library

    Lu, Junxuan

    2007-01-01

    The purpose of this research is to gain a better understanding of the biochemical pathways and molecular targets for the selective induction of apoptosis signaling and execution of prostate cancer (PCa...

  6. Methylselenium and Prostate Cancer Apoptosis

    National Research Council Canada - National Science Library

    Lu, Junxuan

    2003-01-01

    The purpose of this research is to gain a better understanding of the biochemical pathways and molecular targets for the selective induction of apoptosis signaling and execution of PCa cells by methyl selenium (Se...

  7. Methylselenium and Prostate Cancer Apoptosis

    National Research Council Canada - National Science Library

    Lu, Junxuan

    2004-01-01

    The purpose of this research is to gain a better understanding of the biochemical pathways and molecular targets for the selective induction of apoptosis signaling and execution of PCa cells by methyl selenium (Se)/selenol...

  8. Methylselenium and Prostate Cancer Apoptosis

    National Research Council Canada - National Science Library

    Lu, Junxuan

    2005-01-01

    The purpose of this research is to gain a better understanding of the biochemical pathways and molecular targets for the selective induction of apoptosis signaling and execution of prostate cancer (PCa...

  9. Flavonoids products from Nitraria retusa leaves promote lymphoblastoid cells apoptosis.

    Science.gov (United States)

    Jihed, Boubaker; Bhouri, Wissem; Ben Sghaier, Mohammed; Bouhlel, Ines; Kriffi, Mounira; Skandrani, Ines; Dijoux, Franca Marie Genviève; Ghedira, Kamel; Chekir-Ghedira, Leila

    2012-01-01

    In this report, the ethyl acetate extract and its major constituent, isorhamnetin 3-o-robinobioside (I3-O-Rob), from Nitraria retusa (N. Retusa) leaf extracts were evaluated for their ability to induce apoptosis in human lymphoblastoid cells (TK6). Apoptosis of TK6 cell line was carried out using DNA fragmentation, poly ADP-ribose polymerase (PARP) cleavage with reference to caspase-3 activity. These tested products, from N. Retusa, enhanced the apoptosis effects in the tested cancer cell line. This result was confirmed by DNA fragmentation and PARP cleavage indicating a release of caspase-3 level. Our results indicate that the original ethyl acetate extract and the I3-O-Rob have a great antiproliferative effect on human lymphoblastoid cells (TK6), which may be due to their involvement in the apoptotic pathway.

  10. Flavopiridol suppresses tumor necrosis factor-induced activation of activator protein-1, c-Jun N-terminal kinase, p38 mitogen-activated protein kinase (MAPK), p44/p42 MAPK, and Akt, inhibits expression of antiapoptotic gene products, and enhances apoptosis through cytochrome c release and caspase activation in human myeloid cells.

    Science.gov (United States)

    Takada, Yasunari; Sethi, Gautam; Sung, Bokyung; Aggarwal, Bharat B

    2008-05-01

    Although flavopiridol, a semisynthetic flavone, was initially thought to be a specific inhibitor of cyclin-dependent kinases, it has now been shown that flavopiridol mediates antitumor responses through mechanism(s) yet to be defined. We have shown previously that flavopiridol abrogates tumor necrosis factor (TNF)-induced nuclear factor-kappaB (NF-kappaB) activation. In this report, we examined whether this flavone affects other cellular responses activated by TNF. TNF is a potent inducer of activator protein-1 (AP-1), and flavopiridol abrogated this activation in a dose- and time-dependent manner. Flavopiridol also suppressed AP-1 activation induced by various carcinogens and inflammatory stimuli. When examined for its effect on other signaling pathways, flavopiridol inhibited TNF-induced activation of various mitogen-activated protein kinases, including c-Jun NH(2)-terminal kinase (JNK), p38 mitogen-activated protein kinase (MAPK), and p44/p42 MAPK. It is noteworthy that this flavone also suppressed TNF-induced activation of Akt, a cell survival kinase, and expression of various antiapoptotic proteins, such as IAP-1, IAP-2, XIAP, Bcl-2, Bcl-xL, and TRAF-1. Flavopiridol also inhibited the TNF-induced induction of intercellular adhesion molecule-1, c-Myc, and c-Fos, all known to mediate tumorigenesis. Moreover, TNF-induced apoptosis was enhanced by flavopiridol through activation of the bid-cytochrome-caspase-9-caspase-3 pathway. Overall, our results clearly suggest that flavopiridol interferes with the TNF cell-signaling pathway, leading to suppression of antiapoptotic mechanisms and enhancement of apoptosis.

  11. Modulation of iridovirus-induced apoptosis by endocytosis, early expression, JNK, and apical caspase.

    Science.gov (United States)

    Chitnis, Nilesh S; D'Costa, Susan M; Paul, Eric R; Bilimoria, Shän L

    2008-01-20

    Chilo iridescent virus (CIV) is the type species for the family Iridoviridae, which are large, isometric, cytoplasmic dsDNA viruses. We examined the mechanism of apoptosis induction by CIV. High CIV doses (CIV(XS); 400 microg/ml), UV-irradiated virus (CIV(UV); 10 microg/ml) and CVPE (CIV protein extract; 10 microg/ml) induced apoptosis in 60% of treated Choristoneura fumiferana (IPRI-CF-124T) cells. Normal doses of infectious CIV (10 microg/ml) induced apoptosis in only 10% of C. fumiferana (CF) cells. Apoptosis was inhibited by Z-IETD-FMK, an apical caspase inhibitor, indicating that CIV-induced apoptosis requires caspase activity. The putative caspase in CF cells was designated Cf-caspase-i. CIV(UV) or CVPE enhanced Cf-caspase-i activity by 80% at 24 h relative to mock-treated cells. Since the MAP kinase pathway induces or inhibits apoptosis depending on the context, we used JNK inhibitor SP600125 and demonstrated drastic suppression of CVPE-induced apoptosis. Thus, the JNK signaling pathway is significant for apoptosis in this system. Virus interaction with the cell surface was not sufficient for apoptosis since CIV(UV) particles bound to polysterene beads failed to induce apoptosis. Endocytosis inhibitors (bafilomycin or ammonium chloride) negated apoptosis induction by CIV(UV), CIV(XS) or CVPE indicating that entry through this mode is required. Given the weak apoptotic response to infectious CIV, we postulated that viral gene expression inhibited apoptosis. CIV infection of cells pretreated with cycloheximide induced apoptosis in 69% of the cells compared to 10% in normal infections. Furthermore, blocking viral DNA replication with aphidicolin or phosphonoacetic acid suppressed apoptosis and Cf-caspase-i activity, indicating that early viral expression is necessary for inhibition of apoptosis, and de novo synthesis of viral proteins is not required for induction. We show for the first time that, in a member of the family Iridoviridae, apoptosis: (i) requires

  12. Serine racemase: a key player in apoptosis and necrosis

    Directory of Open Access Journals (Sweden)

    Nadia eCanu

    2014-04-01

    Full Text Available A fine balance between cell survival and cell death is required to sculpt the nervous system during development. However, an excess of cell death can occur following trauma, exposure to neurotoxins or alcohol, and some developmental and neurodegenerative diseases, such as Alzheimer’s disease (AD. N-Methyl-D-aspartate receptors (NMDARs support synaptic plasticity and survival of many neuronal populations whereas inappropriate activation may promote various forms of cell death, apoptosis and necrosis representing the two extremes of a continuum of cell death processes both in vitro and in vivo. Hence, by identifying the switches controlling pro-survival vs. apoptosis and apoptosis vs. pro-excitotoxic outcome of NMDAR stimulation, NMDAR modulators could be developed that selectively block the cell death enhancing pro-survival signaling or synaptic plasticity mediated by NMDAR. Among these modulators, a role is emerging for the enzyme serine racemase (SR that synthesizes D-serine, a key co-agonist with glutamate at NMDAR. This review summarizes the experimental evidence from in vitro neuronal cultures -- with special emphasis on cerebellar granule neurons (CGNs -- and in vivo models of neurodegeneration, where the dual role of the SR/D-serine pathway as a master regulator of apoptosis and the apoptosis-necrosis shift will be discussed.

  13. Osteoblasts Protect AML Cells from SDF-1-Induced Apoptosis

    Science.gov (United States)

    Kremer, Kimberly N.; Dudakovic, Amel; McGee-Lawrence, Meghan E.; Philips, Rachael L.; Hess, Allan D.; Smith, B. Douglas; van Wijnen, Andre J.; Karp, Judith E.; Kaufmann, Scott H.; Westendorf, Jennifer J.; Hedin, Karen E.

    2014-01-01

    The bone marrow provides a protective environment for acute myeloid leukemia (AML) cells that often allows leukemic stem cells to survive standard chemotherapeutic regimens. Targeting these leukemic stem cells within the bone marrow is critical for preventing relapse. We recently demonstrated that SDF-1, a chemokine abundant in the bone marrow, induces apoptosis in AML cell lines and in patient samples expressing high levels of its receptor, CXCR4. Here we show that a subset of osteoblast lineage cells within the bone marrow can protect AML cells from undergoing apoptosis in response to the SDF-1 naturally present in that location. In co-culture systems, osteoblasts at various stages of differentiation protected AML cell lines and patient isolates from SDF-1-induced apoptosis. The differentiation of the osteoblast cell lines, MC3T3 and W-20-17, mediated this protection via a cell contact-independent mechanism. In contrast, bone marrow-derived mesenchymal cells, the precursors of osteoblasts, induced apoptosis in AML cells via a CXCR4-dependent mechanism and failed to protect AML cells from exogenously added SDF-1. These results indicate that osteoblasts in the process of differentiation potently inhibit the SDF-1-driven apoptotic pathway of CXCR4-expressing AML cells residing in the bone marrow. Drugs targeting this protective mechanism could potentially provide a new approach to treating AML by enhancing the SDF-1-induced apoptosis of AML cells residing within the bone marrow microenvironment. PMID:24851270

  14. Endoplasmic reticulum stress mediates the arsenic trioxide-induced apoptosis in human hepatocellular carcinoma cells.

    Science.gov (United States)

    Zhang, Xin-Yu; Yang, Shu-Meng; Zhang, Hao-Peng; Yang, Yue; Sun, Shi-Bo; Chang, Jian-Ping; Tao, Xuan-Chen; Yang, Tuo-Yun; Liu, Chun; Yang, Yan-Mei

    2015-11-01

    Arsenic trioxide has been proven to trigger apoptosis in human hepatocellular carcinoma cells. Endoplasmic reticulum stress has been known to be involved in apoptosis through the induction of CCAAT/enhancer-binding protein homologous protein. However, it is unknown whether endoplasmic reticulum stress mediates arsenic trioxide-induced apoptosis in human hepatocellular carcinoma cells. Our data showed that arsenic trioxide significantly induced apoptosis in human hepatocellular carcinoma cells. Furthermore, arsenic trioxide triggered endoplasmic reticulum stress, as indicated by endoplasmic reticulum dilation, upregulation of glucose-regulated protein 78 and CCAAT/enhancer-binding protein homologous protein. We further found that 4-phenylbutyric acid, an inhibitor of endoplasmic reticulum stress, alleviated arsenic trioxide-induced expression of CCAAT/enhancer-binding protein homologous protein. More important, knockdown of CCAAT/enhancer-binding protein homologous protein by siRNA or inhibition of endoplasmic reticulum stress by 4-phenylbutyric acid alleviated apoptosis induced by arsenic trioxide. Consequently, our results suggested that arsenic trioxide could induce endoplasmic reticulum stress-mediated apoptosis in hepatocellular carcinoma cells, and that CCAAT/enhancer-binding protein homologous protein might play an important role in this process. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Villous trophoblast apoptosis is elevated and restricted to cytotrophoblasts in pregnancies complicated by preeclampsia, IUGR, or preeclampsia with IUGR.

    Science.gov (United States)

    Longtine, M S; Chen, B; Odibo, A O; Zhong, Y; Nelson, D M

    2012-05-01

    Human placental villi are surfaced by an outer multinucleated syncytiotrophoblast and underlying mononucleated cytotrophoblasts. Conflicting data have attributed one, or the other, of these villous trophoblast phenotypes to undergo enhanced apoptosis in complicated pregnancies, compared to term, normotensive pregnancies. We use high-resolution confocal microscopy after co-staining for E-cadherin, as a trophoblast plasma membrane marker, and for the cleavage products of cytokeratin 18 and PARP1, as markers for caspase-mediated apoptosis, to distinguish between apoptotic cytotrophoblasts and apoptosis within the syncytiotrophoblast. We test the hypothesis that increased caspase-mediated apoptosis occurs in villi of placentas derived from pregnancies complicated by preeclampsia, intrauterine growth restriction (IUGR), or both. We find significantly elevated apoptosis in villous cytotrophoblasts from women with preeclampsia and/or IUGR, compared to term, normotensive pregnancies. Apoptosis of cytotrophoblasts in villi from complicated pregnancies appears to progress similarly to what we found previously for apoptotic cytotrophoblasts in villi from in term, normotensive pregnancies. Notably, caspase-mediated apoptosis was not detectable in regions with intact syncytiotrophoblast, suggesting strong repression of apoptosis in this trophoblast phenotype in vivo. We suggest that the elevated apoptosis in cytotrophoblasts in preeclampsia contributes to the placental dysfunction characteristic of this disorder. We also propose that repression of apoptosis in the syncytiotrophoblast is important to prevent apoptosis sweeping throughout the syncytium, which would result in widespread death of this essential interface for maternal-fetal exchange. Copyright © 2012 Elsevier Ltd. All rights reserved.

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

    Science.gov (United States)

    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 < .05). Increased cellular uptake of the fluorophore calcein associated with 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.

  17. Placental apoptosis in recurrent miscarriage

    Directory of Open Access Journals (Sweden)

    Tarek A. Atia

    2017-09-01

    Full Text Available Apoptosis is an interactive and dynamic biological process involved in all phases of embryogenesis. We aimed to study the effect of placental apoptosis on recurrent miscarriage (RM. Placental tissue samples were collected from 40 women with RM (study group and 30 women with sporadic spontaneous abortion (control group. Samples were prepared and stained immunohistochemically with markers for both the apoptotic protein (p53 and anti-apoptotic Bcl-2 antibodies. Our results showed that expression of the apoptotic (p53 protein was significantly increased in the placental tissues of the RM group (p = 0.003. By contrast, the expression of anti-apoptotic (Bcl-2 antibodies was significantly increased in the placental tissues of the control group (p = 0.025. We concluded that placental apoptosis plays a crucial role in pregnancy continuation. However, increased p53 expression in placental tissue in early pregnancy could negatively affect pregnancy continuation.

  18. NF-κB p65 recruited SHP regulates PDCD5-mediated apoptosis in cancer cells.

    Science.gov (United States)

    Murshed, Farhan; Farhana, Lulu; Dawson, Marcia I; Fontana, Joseph A

    2014-03-01

    Transcription factor NF-κB promotes cell proliferation in response to cell injury. Increasing evidence, however, suggests that NF-κB can also play an apoptotic role depending on the stimulus and cell type. We have previously demonstrated that novel retinoid 4-[3-Cl-(1-adamantyl)-4-hydroxyphenyl]-3-chlorocinnamic acid (3-Cl-AHPC)-mediated apoptosis in breast carcinoma cells requires activation of canonical and non-canonical NF-κB pathways. The mechanism NF-κB uses to induce apoptosis remains largely unknown. NF-κB subunit p65 (RelA) was identified as one potent transcriptional activator in 3-Cl-AHPC-mediated apoptosis in cells. Here we used ChIP-on-chip to identify NF-κB p65 genes activated in 3-Cl-AHPC mediated apoptosis. This paper focuses on one hit: pro-apoptotic protein programmed cell death 5 (PDCD5). 3-Cl-AHPC mediated apoptosis in MDA-MB-468 had three related effects on PDCD5: NF-κB p65 binding to the PDCD5 gene, enhanced PDCD5 promoter activity, and increased PDCD5 protein expression. Furthermore, 3-Cl-AHPC increased orphan nuclear receptor small heterodimer partner (SHP) mRNA expression, increased SHP protein bound to NF-κB p65, and found the SHP/NF-κB p65 complex attached to the PDCD5 gene. PDCD5 triggered apoptosis through increased Bax protein and release of cytochrome C from mitochondria to cytosol. Lastly, knockdown of PDCD5 protein expression blocked 3-Cl-AHPC mediated apoptosis, while over-expression of PDCD5 enhanced apoptosis, suggesting PDCD5 is necessary and sufficient for NF-κB p65 mediated apoptosis. Our results demonstrate a novel pathway for NF-κB p65 in regulating apoptosis through SHP and PDCD5.

  19. Evaluation of preventive and therapeutic activity of novel non-steroidal anti-inflammatory drug, CG100649, in colon cancer: Increased expression of TNF-related apoptosis-inducing ligand receptors enhance the apoptotic response to combination treatment with TRAIL.

    Science.gov (United States)

    Woo, Jong Kyu; Kang, Ju-Hee; Jang, Yeong-Su; Ro, Seonggu; Cho, Joong Myung; Kim, Hwan-Mook; Lee, Sang-Jin; Oh, Seung Hyun

    2015-04-01

    Non-steroidal anti-inflammatory drugs (NSAIDs) have been suggested as the potential new class of preventive or therapeutic antitumor agents. The aim of the present study was to evaluate the antitumor activity of the novel NSAID, CG100649. CG100649 is a novel NSAID dual inhibitor for COX-2 and carbonic anhydrase (CA)-I/-II. In the present study, we investigated the alternative mechanism by which CG100649 mediated suppression of the colon cancer growth and development. The anchorage‑dependent and -independent clonogenic assay showed that CG100649 inhibited the clonogenicity of human colon cancer cells. The flow cytometric analysis showed that CG100649 induced the G2/M cell cycle arrest in colon cancer cells. Animal studies showed that CG100649 inhibited the tumor growth in colon cancer xenograft in nude mice. Furthermore, quantitative PCR and FACS analysis demonstrated that CG100649 upregulated the expression of TNF-related apoptosis-inducing ligand (TRAIL) receptors (DR4 and DR5) but decreased the expression of decoy receptors (DcR1 and DcR2) in colon cancer cells. The results showed that CG100649 treatment sensitized TRAIL‑mediated growth suppression and apoptotic cell death. The combination treatment resulted in significant repression of the intestinal polyp formation in APCmin/+ mice. Our data clearly demonstrated that CG100649 contains preventive and therapeutic activity for colon cancer. The present study may be useful for identification of the potential benefit of the NSAID CG100649, for the achievement of a better treatment response in colon cancer.

  20. The mechanism of PDT-induced apoptosis

    Science.gov (United States)

    Cai, Xiongwei; Liu, Timon C.; Ding, Xin-Min; Gu, Ying; Liu, Fan-Guang; Liu, Song-Hao

    2003-12-01

    Photodynamic therapy (PDT) can induce apoptosis in many cancer cells in vitro and in tumors in vivo. Cells become more oxidation with PDT, and maintain differentiation and proliferation, go apoptosis and necrosis with the increase of reactive oxygen species (ROS) concentration. ROS can induce apoptosis through mitochondria by inhibiting respiration chain or oxidative phosphorylation or damaging mitochondrial membrane. ROS can initiate apoptosis through endoplamic reticulum(ER) by opening Ca2+ channel or starting unfold protein response (UPR). ROS can also induce apoptosis through Golgi by producing ganglioside GD3 by use of ceramide, which induces apoptosis by activating caspase-3, JNK and p38 MAPK. It can also induce apoptosis by activating Bip (mitochondria-dependant) or preocaspase-12 (mitochondria- independent) or inhibiting protein synthesizing. There are so complicated cross-talking among different signal pathways or organnells that we think PDT-induced apoptosis is mediated by multiplex pathways and excessive levels in a refined network.

  1. New markers of apoptosis in children on chronic dialysis.

    Science.gov (United States)

    Musiał, Kinga; Zwolińska, Danuta

    2013-01-01

    Enhanced apoptosis is characteristic for chronic kidney disease (CKD). A specific type of apoptosis, anoikis, is connected with the extracellular matrix turnover and cell detachment. Although E-cadherin, extracellular matrix metalloproteinase inducer (EMMPRIN) and matrix metalloproteinase (MMP)-8 may play an important role in this process, they have not been analyzed in any nephrological aspect, either in CKD. The aim of study was to evaluate the serum concentrations of E-cadherin, EMMPRIN and their potential regulators (MMP-8, MMP-7, TIMP-1, TIMP-2), with relevance to apoptosis/cell damage markers (sFas, sFasL, Hsp27), in children with CKD. 39 CKD children stages 3-4, 26 CKD children stage 5 still on conservative treatment, 19 patients on hemodialysis (HD), 22 children on automated peritoneal dialysis (APD) and 30 controls were examined. Serum concentrations of those parameters were assessed by ELISA. Median E-cadherin, EMMPRIN and MMP-8 values were significantly increased in patients on dialysis versus those in pre-dialysis period and versus controls. The highest values were noticed in the HD subjects. Regression analysis revealed that EMMPRIN and MMP-8 predicted various apoptosis markers, whereas E-cadherin turned out the best predictor of both apoptosis (Hsp27, sFas, sFasL) and matrix turnover (MMP-7, TIMP-1, TIMP-2) indexes in dialyzed patients. Children with CKD are prone to E-cadherin, EMMPRIN and MMP-8 elevation, aggravated by the dialysis commencement and most evident on hemodialysis. Correlations between parameters suggest their role as indexes of apoptosis in children on dialysis. E-cadherin seems the most accurate marker of anoikis in this population.

  2. Quercetin-induced apoptosis prevents EBV infection

    Science.gov (United States)

    Lee, Minjung; Son, Myoungki; Ryu, Eunhyun; Shin, Yu Su; Kim, Jong Gwang; Kang, Byung Woog; Sung, Gi-Ho; Cho, Hyosun; Kang, Hyojeung

    2015-01-01

    Epstein-Barr virus (EBV) is a human gamma-1 herpesvirus that establishes a lifelong latency in over 90% of the world's population. During latency, virus exists predominantly as a chromatin-associated, multicopy episome in the nuclei of a variety of tumor cells derived from B cells, T cells, natural killer (NK) cells, and epithelial cells. Licorice is the root of Glycyrrhiza uralensis or G. glabra that has traditionally cultivated in eastern part of Asia. Licorice was reported to have anti-viral, anti-inflammatory, anti-atopic, hepatoprotective, anti-neurodegenerative, anti-tumor, anti-diabetic effects and so forth. Quercetin and isoliquiritigenin are produced from licorice and highly similar in molecular structure. They have diverse bioactive effects such as antiviral activity, anti-asthmatic activity, anti-cancer activity, anti-inflammation activity, monoamine-oxidase inhibitor, and etc. To determine anti-EBV and anti-EBVaGC (Epstein-Barr virus associated gastric carcinoma) effects of licorice, we investigated antitumor and antiviral effects of quercetin and isoliquiritigenin against EBVaGC. Although both quercetin and isoliquiritigenin are cytotoxic to SNU719 cells, quercetin induced more apoptosis in SNU719 cells than isoliquiritigenin, more completely eliminated DNMT1 and DNMT3A expressions than isoliquiritigenin, and more strongly affects the cell cycle progression of SNU719 than isoliquiritigenin. Both quercetin and isoliquiritigenin induce signal transductions to stimulate apoptosis, and induce EBV gene transcription. Quercetin enhances frequency of F promoter use, whereas isoliquiritigenin enhances frequency of Q promoter use. Quercetin reduces EBV latency, whereas isoliquiritigenin increases the latency. Quercetin increases more the EBV progeny production, and inhibits more EBV infection than isoliquiritigenin. These results indicate that quercetin could be a promising candidate for antiviral and antitumor agents against EBV and human gastric carcinoma

  3. Apoptosis in oral erythema multiforme.

    Science.gov (United States)

    Chrysomali, E; Lozada-Nur, F; Dekker, N P; Papanicolaou, S I; Regezi, J A

    1997-02-01

    Cell death was evaluated in oral erythema multiforme to test the hypothesis that apoptosis may be a mechanism by which keratinocytes die in this condition. Ten erythema multiforme and five control oral mucosa biopsy specimens were evaluated in immunohistochemically stained sections for apoptosis-regulating proteins Bcl-2, Bcl-x, Bax, p53, Fas, and Fas-ligand. Apoptotic keratinocytes, determined by a detection method for DNA fragmentation (TUNEL) and by conventional morphologic criteria were counted per high power field. Keratinocyte staining for Bcl-2 protein was comparable in erythema multiforme and controls. Bcl-x expression was reduced in five erythema multiforme cases. Staining for Bax protein differed in six erythema multiforme cases and showed variable intensity in layers under the parakeratin. Only slight differences in staining patterns of Fas and Fas-ligand proteins were noted between erythema multiforme and controls. The number of apoptotic keratinocytes evaluated by morphologic examination was significantly higher in erythema multiforme (mean per high power field, 0.90 +/- 0.2; controls, 0.06 +/- 0.04; p erythema multiforme, 0.43 +/- 0.1; controls, 0.02 +/- 0.02). Overexpression of p53 protein was seen in basal keratinocytes in five erythema multiforme specimens (mean, 17.5 +/- 4.03 per high power field; controls 1.2 +/- 0.3). There is evidence that cell death in erythema multiforme is at least in part due to apoptosis. The apoptotic mechanism may be related to an altered expression of apoptosis-regulating proteins. Although measurable alterations in the phenotypic expression of Fas and Fas-ligand proteins were not apparent, activation of Fas/Fas-ligand system could still be involved in the induction of apoptosis in erythema multiforme.

  4. Effects of A.marina-Derived Isoquercitrin on TNF-Related Apoptosis-Inducing Ligand Receptor (TRAIL-R) Expression and Apoptosis Induction in Cervical Cancer Cells.

    Science.gov (United States)

    Arumugam, Sathishkumar; Bandil, Kapil; Proksch, Peter; Murugiyan, Kalaiselvam; Bharadwaj, Mausumi

    2017-06-01

    TNF-related apoptosis-inducing ligand (TRAIL) is an anticancer agent, which has greater apoptosis inducing capacity, but most of the cancer cells become resistant to TRAIL-induced apoptosis. The combined treatment of TRAIL with natural products could restore the cancer cell sensitivity to recombinant human TRAIL (rhTRAIL) protein and might enhance the TNF-related apoptosis-inducing ligand receptor (TRAIL-R) expression. This investigation was aimed to isolate flavonoids from leaves of Avicennia marina and evaluate their potential for sensitization of rhTRAIL in human cervical cancer cells (SiHa). The methanolic extract of A.marina leaves were purified and structure was elucidated as isoquercitrin by NMR and LC-MS analysis. Isolated isoquercitrin showed cytotoxicity against SiHa cell line at IC50 of 980 μM. Messenger RNA (mRNA) expression of TRAIL-Rs was quantified by qRT-PCR, combination of isoquercitrin, and/or rhTRAIL increased TRAIL-R1 and TRAIL-R2 gene expression by 7 folds and 4 folds, respectively. Also, FACS assay revealed that combined treatment has increased the early apoptosis up to 7.24%. In the present study, we found that isoquercitrin enhances the mRNA expression of TRAIL-Rs, but the percentage of apoptosis was meager, possibly due to the influence of other anti-apoptotic proteins.

  5. Fish-Oil-Derived DHA-mediated Enhancement of Apoptosis in Acute Lymphoblastic Leukemia Cells is Associated with Accumulation of p53, Downregulation of Survivin, and Caspase-3 Activation.

    Science.gov (United States)

    Sam, Mohammad Reza; Esmaeillou, Mohammad; Shokrgozar, Mohammad Ali

    2017-01-01

    In acute lymphoblastic leukemia (ALL), resistance to chemotherapy is associated with inactivation of p53 and upregulation of survivin. Thus, targeting the p53 and survivin expression may provide an attractive strategy for ALL treatment. It has been shown that fish-oil-derived docosahexaenoic acid (DHA) activates several antitumorigenic mechanisms in tumor cells, but little is known regarding the role of DHA on modulating p53 and survivin expression in ALL cells. In this study, we investigated the alterations of the p53 and survivin expression and induction of apoptosis in DHA-treated Molt-4 cells that serve as a model for ALL cells. Molt-4 cells were treated with 50, 100, 150, and 200 μM DHA after which cell proliferation, survivin mRNA and protein levels, p53 protein level, caspase-3 activation, and apoptotic rates were evaluated by different cellular and molecular techniques. After 48- and 72-h treatments with DHA at concentrations ranging from 50 to 200 μM, cell proliferation rates were measured to be 80.5-44.4%, and 73.4-14.4%, respectively, compared to untreated cells. We also found that treatment for 48 h with 200 μM DHA resulted in 10.8- and 3.6-fold increase in p53 protein level and caspase-3 activation followed by 4.7-and 1.6-fold decrease in survivin mRNA and protein levels, respectively, compared to untreated cells. Treatment of cells with different concentrations of DHA dramatically increased the p53/survivin and caspase-3/survivin ratios by 2.8- to 16.9-fold and 3.3 to 5.6-fold increases, respectively, compared to untreated cells. A decrease in the number of cells ranging from 16% to 70% and an increase in the number of apoptotic cells ranging from 9.3% to 93% was also observed with increasing DHA concentrations. In conclusion, p53 and survivin may provide promising targets of DHA in ALL cells and this compound with high proapoptotic capacity represents the possibility of its therapeutic application for ALL treatment.

  6. HJC, a new arylnaphthalene lignan isolated from Justicia procumbens, causes apoptosis and caspase activation in K562 leukemia cells.

    Science.gov (United States)

    Luo, Jiaoyang; Kong, Weijun; Yang, Meihua

    2014-01-01

    The aim of this study is to investigate whether HJC, isolated from Justicia procumbens for the first time, can suppress the proliferation and induce apoptosis of human leukemia K562 cells and finally clarify its related mechanism. The chemical structure of HJC was validated by LC-ESI-MS/MS, cytotoxicity was assayed using MTT, and apoptosis was investigated by flow cytometry. These assays indicated that HJC remarkably inhibited the growth in K562 cells by decreasing cell proliferation, reducing the SOD activity, enhancing ROS levels and inducing apoptosis. Activation of caspase-3 indicated that HJC may be inducing intrinsic and extrinsic apoptosis pathways and that HJC-induced apoptosis was caspase-dependent. This study suggests that HJC is a high-potency anti-tumor agent, and it induces apoptosis through a caspase-dependent pathway in human leukemia K562 cells. It also presents a potential alternative to leukemia therapy.

  7. Nosema Tolerant Honeybees (Apis mellifera) Escape Parasitic Manipulation of Apoptosis.

    Science.gov (United States)

    Kurze, Christoph; Le Conte, Yves; Dussaubat, Claudia; Erler, Silvio; Kryger, Per; Lewkowski, Oleg; Müller, Thomas; Widder, Miriam; Moritz, Robin F A

    2015-01-01

    Apoptosis is not only pivotal for development, but also for pathogen defence in multicellular organisms. Although numerous intracellular pathogens are known to interfere with the host's apoptotic machinery to overcome this defence, its importance for host-parasite coevolution has been neglected. We conducted three inoculation experiments to investigate in the apoptotic respond during infection with the intracellular gut pathogen Nosema ceranae, which is considered as potential global threat to the honeybee (Apis mellifera) and other bee pollinators, in sensitive and tolerant honeybees. To explore apoptotic processes in the gut epithelium, we visualised apoptotic cells using TUNEL assays and measured the relative expression levels of subset of candidate genes involved in the apoptotic machinery using qPCR. Our results suggest that N. ceranae reduces apoptosis in sensitive honeybees by enhancing inhibitor of apoptosis protein-(iap)-2 gene transcription. Interestingly, this seems not be the case in Nosema tolerant honeybees. We propose that these tolerant honeybees are able to escape the manipulation of apoptosis by N. ceranae, which may have evolved a mechanism to regulate an anti-apoptotic gene as key adaptation for improved host invasion.

  8. Punicalagin promotes autophagy to protect primary human syncytiotrophoblasts from apoptosis.

    Science.gov (United States)

    Wang, Ying; Chen, Baosheng; Longtine, Mark S; Nelson, D Michael

    2016-02-01

    Punicalagin is a prominent polyphenol in pomegranate juice that protects cultured syncytiotrophoblasts from stress-induced apoptosis. Here, we test the hypothesis that punicalagin has this effect by inhibiting the mTOR kinase pathway to enhance autophagic turnover and limit apoptosis in cultured primary human syncytiotrophoblasts. In syncytiotrophoblasts, starvation, rapamycin, or punicalagin all decreased the expression of phosphorylated ribosomal protein S6, a downstream target of the mTOR kinase, and of the autophagy markers, LC3-II and p62. In contrast, in the presence of bafilomycin, an inhibitor of late stages of autophagy and degradation in the autophagolysosome, syncytiotrophoblasts exposed to starvation, rapamycin, or punicalagin all showed increased levels of LC3-II and p62. The number of LC3-II punctae also increased in punicalagin-treated syncytiotrophoblasts exposed to chloroquine, another inhibitor of autophagic degradation, and punicalagin increased the number of lysosomes. The apoptosis-reducing effect of punicalagin was attenuated by inhibition of autophagy using bafilomycin or knockdown of the autophagy related gene, ATG16L1. Collectively, these data support the hypothesis that punicalagin modulates the crosstalk between autophagy and apoptosis to promote survival in cultured syncytiotrophoblasts. © 2016 Society for Reproduction and Fertility.

  9. Thapsigargin induces apoptosis in cultured human aortic smooth muscle cells.

    Science.gov (United States)

    Peiró, C; Vallejo, S; Cercas, E; Llergo, J L; Lafuente, N; Matesanz, N; Rodríguez-Mañas, L; Sánchez-Ferrer, C F

    2000-11-01

    Vascular remodeling is a key feature of many pathologic states, including atherosclerosis, or hypertension. Vascular smooth muscle cells participate in determining the vessel structure by several mechanisms such as cell migration, cell growth, or cell death (necrosis or apoptosis). Here we report that thapsigargin, an inhibitor of endoplasmic reticulum Ca2+ -adenosine triphosphatase (ATPase), is able to induce apoptosis in human vascular smooth muscle cells (HVSMCs). Apoptosis was assessed by three different methods: differential chromatin binding dye staining. cytoplasmic histone-associated DNA fragments detection by enzyme-linked immunosorbent assay (ELISA) and terminal deoxyribonucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL). When HVSMCs were treated for 1 h with thapsigargin (100 nM-10 microM), there was a concentration-dependent increase in both parameters 24 h after the thapsigargin pulse. When a time-course experiment was performed, both parameters were significantly enhanced from 3 to 6 h after the exposure to thapsigargin. We conclude that thapsigargin promotes apoptosis in HVSMCs, providing a useful tool for the study of programmed cell death in human vascular smooth muscle.

  10. alpha-Amanitin induced apoptosis in primary cultured dog hepatocytes.

    Directory of Open Access Journals (Sweden)

    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. Iron starvation induces apoptosis in Rhizopus oryzae in vitro.

    Science.gov (United States)

    Shirazi, Fazal; Kontoyiannis, Dimitrios P; Ibrahim, Ashraf S

    2015-01-01

    Mortality associated with mucormycosis remains high despite current antifungals. Iron-starvation strategies have been shown to have promising activity against Mucorales. We hypothesized that iron starvation enhances apoptosis in Rhizopus oryzae. Apoptosis was characterized in R. oryzae transformed with RNAi plasmid targeting FTR1 expression (iron permease mutant) or empty plasmid grown in iron rich (0.125% FeCl3) and iron depleted media (YNB+1mM ferrozine and 1 mM ascorbic acid). Increased apoptosis was observed with dihydrorhodamine-123 and rhodamine-123 staining in the iron starved mutant FTR1 when compared to empty plasmid, followed by increased extracellular ATP levels. In addition, DNA fragmentation and metacaspase activity were prominent in FTR1. In contrast, Rhizopus strains grown in iron-rich medium displayed minimal apoptosis. Our results demonstrate a metacaspase dependent apoptotic process in iron deprived condition and further support the role of iron starvation strategies as an adjunct treatment for mucormycosis, a mechanism by which iron starvation affects R. oryzae.

  12. Fangchinoline Induces Apoptosis, Autophagy and Energetic Impairment in Bladder Cancer

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    Bo Fan

    2017-10-01

    Full Text Available Background/Aims: Tetrandrine and Fangchinoline (Fcn are two natural products that are found in Stephania tetrandra. Tetrandrine is a known anti-bladder cancer compound, but the effects of Fcn on bladder cancer have been previously unclear. In the present study, we focused on the anti-tumor effects of Fcn on bladder cancer. Methods and Results: We treated T24 and 5637 bladder cancer cell lines with Fcn in vitro. We observed that Fcn inhibited the viability of bladder cancer cells in a concentration-dependent manner. The expression of PCNA, a biomarker of proliferation, was down-regulated. Fcn treatment induced both apoptosis and autophagy in bladder cancer cells, as shown by the increased cleavage of caspase-3, an up-regulated LC3-II/LC3-I ratio and the down-regulated p62 level. Blocking autophagy with 3-MA (3-Methyladenine enhanced Fcn-induced apoptosis, indicating that Fcn-induced autophagy was adaptive. Additionally, we observed that Fcn treatment inhibited mTOR and reduced the intracellular ATP levels. The exogenous addition of methyl pyruvate (MP to compensate metabolic substrates alleviated Fcn-induced apoptosis and autophagy. Conclusions: Our data indicated that Fcn caused an impairment in energy generation, which led to apoptosis and adaptive autophagy in bladder cancer. These results demonstrated that Fcn may be a potential candidate for use in the prevention and treatment of bladder cancer.

  13. The role of apoptosis in pulmonary fibrosis

    Directory of Open Access Journals (Sweden)

    B. D. Uhal

    2008-12-01

    Full Text Available Apoptosis has been defined as "gene-directed cellular self-destruction" and is an active process that is tightly regulated by a number of gene products, which promote or block cell death. Apoptotic death can be triggered by a wide variety of stimuli and, importantly, not all cells necessarily undergo apoptosis in response to the same stimulus. Abnormal regulation of apoptosis has been implicated in a wide range of diseases and approaches to modifying apoptosis represent important future therapeutic strategies. Idiopathic pulmonary fibrosis (IPF is a progressive and relentless disease involving scarring of the lung, which has been recognised as the most lethal interstitial lung disease. In the lungs of IPF patients, increased epithelial apoptosis, together with decreased apoptosis of myofibroblasts, represents persistent findings (particularly in areas of collagen deposition supporting an interaction between altered apoptosis and the pathogenesis of the disease. Data from human tissues and animal models are refining current knowledge of the processes involved in this pathogenesis. This has challenged the dogma that IPF is purely a disease of unresolved inflammation by emphasising the central roles played by the alveolar epithelial cell and myofibroblasts and, as part of that role, the importance of altered apoptosis. Evidence suggests blockade of epithelial cell apoptosis can prevent subsequent collagen deposition, and induction of myofibroblast apoptosis, at least theoretically, would be expected to resolve ongoing fibrosis. These two concepts raise the prospect of therapeutic intervention aimed at modifying apoptosis and, thus, fibrosis in idiopathic pulmonary fibrosis.

  14. Naringin prevents ovariectomy-induced osteoporosis and promotes osteoclasts apoptosis through the mitochondria-mediated apoptosis pathway

    Energy Technology Data Exchange (ETDEWEB)

    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.

  15. PD-1 blockade restores impaired function of ex vivo expanded CD8+ T cells and enhances apoptosis in mismatch repair deficient EpCAM+PD-L1+ cancer cells

    Directory of Open Access Journals (Sweden)

    Kumar R

    2017-07-01

    Full Text Available Rajeev Kumar,1,2 Fang Yu,1 Yuan-Huan Zhen,3 Bo Li,2 Jun Wang,1 Yuan Yang,1,2 Hui-Xin Ge,4 Ping-Sheng Hu,1,2 Jin Xiu1,2 1Clinical Research Centre, The Affiliated Hospital of Guizhou Medical University, Guiyang, People’s Republic of China; 2Cancer Immunology and Immunotherapy Centre, The Affiliated Hospital of Guizhou Medical University, Guiyang, People’s Republic of China; 3Department of Colorectal Surgery, The Affiliated Hospital of Guizhou Medical University, Guiyang, People’s Republic of China; 4Department of Surgery, The Affiliated Cancer Hospital of Guizhou Medical University, Guiyang, People’s Republic of China Background: Adoptive T cell therapy has been proven to be a promising modality for the treatment of cancer patients in recent years. However, the increased expression of inhibitory receptors could negatively regulate the function and persistence of transferred T cells which mediates T cell anergy, exhaustion, and tumor regression. In this study, we investigated increased cytotoxic activity after the blockade of PD-1 for effective immunotherapy.Methods: The cytotoxic function of expanded CD8+ CTLs and interactions with tumor cells investigated after blocking of PD-1. Ex vivo expanded CD8+ CTLs were co-cultured with mismatch repair (MMR stable or deficient (high microsatellite instability [MSI-H] EpCAM+ tumor cells. The levels of IFN-γ and GrB were detected by enzyme-linked immunosorbent spot assay. Flow cytometry and confocal microscopy were used to assess CD107a mobilization, cytosolic uptake, and cell migration. Results: A dramatic increase in PD-1 expression on the surface of CD8+ CTLs during ex vivo expansion was observed. PD-1 level was downregulated by approximately 40% after incubation of the CD8+ CTLs with monoclonal antibody which enhanced the secretion of IFN-γ, GrB, and CD107a. Additionally, PD-1 blockade enhanced cell migration and cytosolic exchange between CD8+ CTLs and MMR deficient (MSI-H EpCAM+PD-L1+ tumor

  16. Caveolin-1 sensitizes rat pituitary adenoma GH3 cells to bromocriptine induced apoptosis

    Directory of Open Access Journals (Sweden)

    Huang Mu-Chiou

    2007-03-01

    Full Text Available Abstract Background Prolactinoma is the most frequent pituitary tumor in humans. The dopamine D2 receptor agonist bromocriptine has been widely used clinically to treat human breast tumor and prolactinoma through inhibition of hyperprolactinemia and induction of tumor cell apoptosis, respectively, but the molecular mechanism of bromocriptine induction of pituitary tumor apoptosis remains unclear. Caveolin-1 is a membrane-anchored protein enriched on caveolae, inverted flask-shaped invaginations on plasma membranes where signal transduction molecules are concentrated. Currently, caveolin-1 is thought to be a negative regulator of cellular proliferation and an enhancer of apoptosis by blocking signal transduction between cell surface membrane receptors and intracellular signaling protein cascades. Rat pituitary adenoma GH3 cells, which express endogenous caveolin-1, exhibit increased apoptosis and shrinkage after exposure to bromocriptine. Hence, the GH3 cell line is an ideal model for studying the molecular action of bromocriptine on prolactinoma. Results The expression of endogenous caveolin-1 in GH3 cells was elevated after bromocriptine treatment. Transiently expressed mouse recombinant caveolin-1 induced apoptosis in GH3 cells by enhancing the activity of caspase 8. Significantly, caveolin-1 induction of GH3 cell apoptosis was sensitized by the administration of bromocriptine. Phosphorylation of caveolin-1 at tyrosine 14 was enhanced after bromocriptine treatment, suggesting that bromocriptine-induced phosphorylation of caveolin-1 may contribute to sensitization of apoptosis in GH3 cells exposed to bromocriptine. Conclusion Our results reveal that caveolin-1 increases sensitivity for apoptosis induction in pituitary adenoma GH3 cells and may contribute to tumor shrinkage after clinical bromocriptine treatment.

  17. Crosstalk between autophagy and apoptosis in RAW 264.7 macrophages infected with ectromelia orthopoxvirus.

    Science.gov (United States)

    Martyniszyn, Lech; Szulc-Dąbrowska, Lidia; Boratyńska-Jasińska, Anna; Struzik, Justyna; Winnicka, Anna; Niemiałtowski, Marek

    2013-10-01

    Several studies have provided evidence that complex relationships between autophagic and apoptotic cell death pathways occur in cancer and virus-infected cells. Previously, we demonstrated that infection of macrophages with Moscow strain of ectromelia virus (ECTV-MOS) induces apoptosis under in vitro and in vivo conditions. Here, we found that autophagy was induced in RAW 264.7 cells during infection with ECTV-MOS. Silencing of beclin 1, an autophagy-related gene, reduced the percentage of late apoptotic cells in virus-infected RAW 264.7 macrophages. Pharmacological modulation of autophagy by wortmannin (inhibitor) or rapamycin (inductor) did not affect or cause increased apoptosis in ECTV-MOS-infected RAW 264.7 cells, respectively. Meantime, blocking apoptosis by a pan-caspase inhibitor, Z-VAD-FMK, increased the formation of autophagosomes in infected macrophages. Taken together, three important points arise from our study. First, autophagy may co-occur with apoptosis in RAW 264.7 cells exposed to ECTV-MOS. Second, at later stages of infection, autophagy may partially participate in the execution of macrophage cell death by enhancing apoptosis. Third, when apoptosis is blocked infected macrophages undergo increased autophagy. Our results provide new information about the relationship between autophagy and apoptosis in ECTV-MOS-infected macrophages.

  18. Dihydroartemisinin induces apoptosis preferentially via a Bim-mediated intrinsic pathway in hepatocarcinoma cells.

    Science.gov (United States)

    Qin, Guiqi; Zhao, ChuBiao; Zhang, Lili; Liu, Hongyu; Quan, Yingyao; Chai, Liuying; Wu, Shengnan; Wang, Xiaoping; Chen, Tongsheng

    2015-08-01

    This report is designed to dissect the detail molecular mechanism by which dihydroartemisinin (DHA), a derivative of artemisinin, induces apoptosis in human hepatocellular carcinoma (HCC) cells. DHA induced a loss of the mitochondrial transmemberane potential (ΔΨm), release of cytochrome c, activation of caspases, and externalization of phosphatidylserine indicative of apoptosis induction. Compared with the modest inhibitory effects of silencing Bax, silencing Bak largely prevented DHA-induced ΔΨm collapse and apoptosis though DHA induced a commensurable activation of Bax and Bak, demonstrating a key role of the Bak-mediated intrinsic apoptosis pathway. DHA did not induce Bid cleavage and translocation from cytoplasm to mitochondria and had little effects on the expressions of Puma and Noxa, but did increase Bim and Bak expressions and decrease Mcl-1 expression. Furthermore, the cytotoxicity of DHA was remarkably reduced by silencing Bim, and modestly but significantly reduced by silencing Puma or Noxa. Silencing Bim or Noxa preferentially reduced DHA-induced Bak activation, while silencing Puma preferentially reduced DHA-induced Bax activation, demonstrating that Bim and to a lesser extent Noxa act as upstream mediators to trigger the Bak-mediated intrinsic apoptosis pathway. In addition, silencing Mcl-1 enhanced DHA-induced Bak activation and apoptosis. Taken together, our data demonstrate a crucial role of Bim in preferentially regulating the Bak/Mcl-1 rheostat to mediate DHA-induced apoptosis in HCC cells.

  19. Ripk3 induces mitochondrial apoptosis via inhibition of FUNDC1 mitophagy in cardiac IR injury

    Directory of Open Access Journals (Sweden)

    Hao Zhou

    2017-10-01

    Full Text Available Ripk3-required necroptosis and mitochondria-mediated apoptosis are the predominant types of cell death that largely account for the development of cardiac ischemia reperfusion injury (IRI. Here, we explored the effect of Ripk3 on mitochondrial apoptosis. Compared with wild-type mice, the infarcted area in Ripk3-deficient (Ripk3-/- mice had a relatively low abundance of apoptotic cells. Moreover, the loss of Ripk3 protected the mitochondria against IRI and inhibited caspase9 apoptotic pathways. These protective effects of Ripk3 deficiency were relied on mitophagy activation. However, inhibition of mitophagy under Ripk3 deficiency enhanced cardiomyocyte and endothelia apoptosis, augmented infarcted area and induced microvascular dysfunction. Furthermore, ischemia activated mitophagy by modifying FUNDC1 dephosphorylation, which substantively engulfed mitochondria debris and cytochrome-c, thus blocking apoptosis signal. However, reperfusion injury elevated the expression of Ripk3 which disrupted FUNDC1 activation and abated mitophagy, increasing the likelihood of apoptosis. In summary, this study confirms the promotive effect of Ripk3 on mitochondria-mediated apoptosis via inhibition of FUNDC1-dependent mitophagy in cardiac IRI. These findings provide new insight into the roles of Ripk3-related necroptosis, mitochondria-mediated apoptosis and FUNDC1-required mitophagy in cardiac IRI.

  20. Helicobacter pylori sensitizes TNF-related apoptosis-inducing ligand (TRAIL)-mediated apoptosis in human gastric epithelial cells through regulation of FLIP.

    Science.gov (United States)

    Lin, W-C; Tsai, H-F; Liao, H-J; Tang, C-H; Wu, Y-Y; Hsu, P-I; Cheng, A-L; Hsu, P-N

    2014-03-06

    Helicobacter pylori (H. pylori) infection is associated with chronic gastritis, peptic ulcer and gastric cancer. Apoptosis induced by microbial infections is implicated in the pathogenesis of H. pylori infection. Here we show that human gastric epithelial cells sensitized to H. pylori confer susceptibility to TRAIL-mediated apoptosis via modulation of death receptor signaling. Human gastric epithelial cells are intrinsically resistant to TRAIL-mediated apoptosis. The induction of TRAIL sensitivity by H. pylori is dependent on the activation of caspase-8 and its downstream pathway. H. pylori induces caspase-8 activation via enhanced assembly of the TRAIL death-inducing signaling complex (DISC) through downregulation of cellular FLICE-inhibitory protein (FLIP). Overexpression of FLIP abolished the H. pylori-induced TRAIL sensitivity in human gastric epithelial cells. Our study thus demonstrates that H. pylori induces sensitivity to TRAIL apoptosis by regulation of FLIP and assembly of DISC, which initiates caspase activation, resulting in the breakdown of resistance to apoptosis, and provides insight into the pathogenesis of gastric damage in Helicobacter infection. Modulation of host apoptosis signaling by bacterial interaction adds a new dimension to the pathogenesis of Helicobacter.

  1. Metformin promotes autophagy and apoptosis in esophageal squamous cell carcinoma by downregulating Stat3 signaling

    Science.gov (United States)

    Feng, Y; Ke, C; Tang, Q; Dong, H; Zheng, X; Lin, W; Ke, J; Huang, J; Yeung, S-CJ; Zhang, H

    2014-01-01

    The antidiabetic drug metformin exerts chemopreventive and antineoplastic effects in many types of malignancies. However, the mechanisms responsible for metformin actions appear diverse and may differ in different types of cancer. Understanding the molecular and cellular mechanisms specific for different cancers is important to optimize strategy for metformin treatment in different cancer types. Here, we investigate the in vitro and in vivo effects of metformin on esophageal squamous cell carcinoma (ESCC) cells. Metformin selectively inhibited cell growth in ESCC tumor cells but not immortalized noncancerous esophageal epithelial cells. In addition to apoptosis, metformin triggered autophagy. Pharmacological or genetic inhibition of autophagy sensitized ESCC cells to metformin-induced apoptotic cell death. Mechanistically, signal transducer and activator of transcription 3 (Stat3) and its downstream target Bcl-2 was inactivated by metformin treatment. Accordingly, small interfering RNA (siRNA)-mediated Stat3 knockdown enhanced metformin-induced autophagy and apoptosis, and concomitantly enhanced the inhibitory effect of metformin on cell viability. Similarly, the Bcl-2 proto-oncogene, an inhibitor of both apoptosis and autophagy, was repressed by metformin. Ectopic expression of Bcl-2 protected cells from metformin-mediated autophagy and apoptosis. In vivo, metformin downregulated Stat3 activity and Bcl-2 expression, induced apoptosis and autophagy, and inhibited tumor growth. Together, inactivation of Stat3-Bcl-2 pathway contributes to metformin-induced growth inhibition of ESCC by facilitating crosstalk between apoptosis and autophagy. PMID:24577086

  2. [Effects of different concentrations of putrescine on proliferation, migration and apoptosis of human skin fibroblasts].

    Science.gov (United States)

    Chen, Jianxia; Rong, Xinzhou; Fan, Guicheng; Li, Songze; Li, Qinghui

    2015-05-01

    To explore the effects of different concentrations of putrescine on the proliferation, migration and apoptosis of human skin fibroblasts (HSF). HSF cultured in the presence of 0.5, 1.0, 5.0, 10, 50, 100, 500, and 1000 µg/ putrescine for 24 h were examined for the changes in the cell proliferation, migration, and apoptosis using MTS assay, Transwell migration assay, and flow cytometry, respectively. Compared with the control cells, HSF cultured with 0.5, 1.0, 5.0, and 10 µg/ putrescine showed significantly increased cell proliferation (Pputrescine, whereas 500 and 1000 µg/ putrescine significantly reduced the cell proliferation (P0.05). Putrescine at 1 µg/ most significantly enhanced the cell migration (Pputrescine significantly suppressed the cell migration (Pputrescine produced no obvious effects on the cell migration (P>0.05). HSF treated with 0.5, 1.0, 5.0, and 10 µg/ putrescine obvious lowered the cell apoptosis rate compared with the control group (Pputrescine; but at the concentrations of 100, 500, and 1000 µg/, putrescine significantly increased the cell apoptosis rate (Pputrescine produced no obvious effect on cell apoptosis (P>0.05). Low concentrations of putrescine can obviously enhance the proliferation ability and maintain normal migration ability of HSF in vitro, but at high concentrations, putrescine can obviously inhibit the cell migration and proliferation and induce cells apoptosis, suggesting the different roles of different concentrations of putrescine in wound healing.

  3. Automatic image analysis of multicellular apoptosis process.

    Science.gov (United States)

    Ziraldo, Riccardo; Link, Nichole; Abrams, John; Ma, Lan

    2014-01-01

    Apoptotic programmed cell death (PCD) is a common and fundamental aspect of developmental maturation. Image processing techniques have been developed to detect apoptosis at the single-cell level in a single still image, while an efficient algorithm to automatically analyze the temporal progression of apoptosis in a large population of cells is unavailable. In this work, we have developed an ImageJ-based program that can quantitatively analyze time-lapse microscopy movies of live tissues undergoing apoptosis with a fluorescent cellular marker, and subsequently extract the temporospatial pattern of multicellular response. The protocol is applied to characterize apoptosis of Drosophila wing epithelium cells at eclosion. Using natural anatomic structures as reference, we identify dynamic patterns in the progression of apoptosis within the wing tissue, which not only confirms the previously observed collective cell behavior from a quantitative perspective for the first time, but also reveals a plausible role played by the anatomic structures in Drosophila apoptosis.

  4. Formaldehyde suppresses neuronal apoptosis via inhibition of outward K(+) currents in rat hippocampus.

    Science.gov (United States)

    Liu, Pei; Guo, Jianli; Qi, Zhi

    2011-11-01

    Formaldehyde (FA) is widely present in the environment, and is also a mammalian metabolite. However, its biological role has not been well understood. Here, we show that FA plays an anti-apoptotic role in cultured hippocampal neurons: FA suppressed staurosporine-induced neuronal apoptosis and inhibited the activity of apoptosis-associated caspase-3/7 proteases in a concentration-dependent manner. Moreover, FA suppressed outward K(+) currents and attenuated the enhanced IK currents that are associated with neuronal apoptosis. As an increase in outward K(+) currents is critical for cell apoptosis, our results suggest that FA exerts its anti-apoptotic effects on neuronal cells, probably through its inhibitory effect on the outward K(+) currents.

  5. Mycobacterium tuberculosis effectors interfering host apoptosis signaling.

    Science.gov (United States)

    Liu, Minqiang; Li, Wu; Xiang, Xiaohong; Xie, Jianping

    2015-07-01

    Tuberculosis remains a serious human public health concern. The coevolution between its pathogen Mycobacterium tuberculosis and human host complicated the way to prevent and cure TB. Apoptosis plays subtle role in this interaction. The pathogen endeavors to manipulate the apoptosis via diverse effectors targeting key signaling nodes. In this paper, we summarized the effectors pathogen used to subvert the apoptosis, such as LpqH, ESAT-6/CFP-10, LAMs. The interplay between different forms of cell deaths, such as apoptosis, autophagy, necrosis, is also discussed with a focus on the modes of action of effectors, and implications for better TB control.

  6. Sorafenib inhibition of Mcl-1 accelerates ATRA induced apoptosis in differentiation responsive AML cells

    Science.gov (United States)

    Wang, Rui; Xia, Lijuan; Gabrilove, Janice; Waxman, Samuel; Jing, Yongkui

    2015-01-01

    Purpose All trans retinoic acid (ATRA) is successful in treating acute promyelocytic leukemia (APL) by inducing terminal differentiation-mediated cell death, but it has limited activity in non-APL acute myeloid leukemia (AML). We aim to improve ATRA therapy of AML by enhancing apoptosis through repression of the anti-apoptotic proteins Bcl-2 and Mcl-1. Experimental Design APL and AML cell lines, as well as primary AML samples, were used to explore the mechanisms regulating differentiation and apoptosis during ATRA treatment. Stable transfection and gene silencing with siRNA were used to identify the key factors that inhibit apoptosis during induction of differentiation and drugs that accelerate apoptosis. Results In differentiation responsive AML cells, ATRA treatment induces long-lasting repression of Bcl-2 while first up-modulating and then reducing the Mcl-1 level. The Mcl-1 level appears to serve as a gatekeeper between differentiation and apoptosis. During differentiation induction, activation of MEK/ERK and PI3K/Akt pathways by ATRA leads to activation of p90RSK and inactivation of glycogen synthase kinase 3β (GSK3β), which increase Mcl-1 levels by increasing its translation and stability. Sorafenib blocks ATRA-induced Mcl-1 increase by reversing p90RSK activation and GSK3β inactivation, maintains the repressed Bcl-2 level, and enhances ATRA induced apoptosis in non-APL AML cell lines and in primary AML cells. Conclusion Inhibition of Mcl-1 is required for apoptosis induction in ATRA differentiation responsive AML cells. ATRA and Sorafenib can be developed as a novel drug combination therapy for AML patients because this drug combination augments apoptosis by inhibiting Bcl-2 and Mcl-1. PMID:26459180

  7. Sorafenib Inhibition of Mcl-1 Accelerates ATRA-Induced Apoptosis in Differentiation-Responsive AML Cells.

    Science.gov (United States)

    Wang, Rui; Xia, Lijuan; Gabrilove, Janice; Waxman, Samuel; Jing, Yongkui

    2016-03-01

    All trans-retinoic acid (ATRA) is successful in treating acute promyelocytic leukemia (APL) by inducing terminal differentiation-mediated cell death, but it has limited activity in non-APL acute myeloid leukemia (AML). We aim to improve ATRA therapy of AML by enhancing apoptosis through repression of the antiapoptotic proteins Bcl-2 and Mcl-1. APL and AML cell lines, as well as primary AML samples, were used to explore the mechanisms regulating differentiation and apoptosis during ATRA treatment. Stable transfection and gene silencing with siRNA were used to identify the key factors that inhibit apoptosis during induction of differentiation and drugs that accelerate apoptosis. In differentiation-responsive AML cells, ATRA treatment induces long-lasting repression of Bcl-2 while first upmodulating and then reducing the Mcl-1 level. The Mcl-1 level appears to serve as a gatekeeper between differentiation and apoptosis. During differentiation induction, activation of MEK/ERK and PI3K/Akt pathways by ATRA leads to activation of p90RSK and inactivation of glycogen synthase kinase 3β (GSK3β), which increase Mcl-1 levels by increasing its translation and stability. Sorafenib blocks ATRA-induced Mcl-1 increase by reversing p90RSK activation and GSK3β inactivation, maintains the repressed Bcl-2 level, and enhances ATRA induced apoptosis in non-APL AML cell lines and in primary AML cells. Inhibition of Mcl-1 is required for apoptosis induction in ATRA differentiation-responsive AML cells. ATRA and sorafenib can be developed as a novel drug combination therapy for AML patients because this drug combination augments apoptosis by inhibiting Bcl-2 and Mcl-1. ©2015 American Association for Cancer Research.

  8. Apoptosis in differentiating C2C12 muscle cells selectively targets Bcl-2-deficient myotubes.

    Science.gov (United States)

    Schöneich, Christian; Dremina, Elena; Galeva, Nadezhda; Sharov, Victor

    2014-01-01

    Muscle cell apoptosis accompanies normal muscle development and regeneration, as well as degenerative diseases and aging. C2C12 murine myoblast cells represent a common model to study muscle differentiation. Though it was already shown that myogenic differentiation of C2C12 cells is accompanied by enhanced apoptosis in a fraction of cells, either the cell population sensitive to apoptosis or regulatory mechanisms for the apoptotic response are unclear so far. In the current study we characterize apoptotic phenotypes of different types of C2C12 cells at all stages of differentiation, and report here that myotubes of differentiated C2C12 cells with low levels of anti-apoptotic Bcl-2 expression are particularly vulnerable to apoptosis even though they are displaying low levels of pro-apoptotic proteins Bax, Bak and Bad. In contrast, reserve cells exhibit higher levels of Bcl-2 and high resistance to apoptosis. The transfection of proliferating myoblasts with Bcl-2 prior to differentiation did not protect against spontaneous apoptosis accompanying differentiation of C2C12 cells but led to Bcl-2 overexpression in myotubes and to significant protection from apoptotic cell loss caused by exposure to hydrogen peroxide. Overall, our data advocate for a Bcl-2-dependent mechanism of apoptosis in differentiated muscle cells. However, downstream processes for spontaneous and hydrogen peroxide induced apoptosis are not completely similar. Apoptosis in differentiating myoblasts and myotubes is regulated not through interaction of Bcl-2 with pro-apoptotic Bcl-2 family proteins such as Bax, Bak, and Bad.

  9. Combinatorial action of Grainyhead, Extradenticle and Notch in regulating Hox mediated apoptosis in Drosophila larval CNS.

    Science.gov (United States)

    Khandelwal, Risha; Sipani, Rashmi; Govinda Rajan, Sriivatsan; Kumar, Raviranjan; Joshi, Rohit

    2017-10-01

    Hox mediated neuroblast apoptosis is a prevalent way to pattern larval central nervous system (CNS) by different Hox genes, but the mechanism of this apoptosis is not understood. Our studies with Abdominal-A (Abd-A) mediated larval neuroblast (pNB) apoptosis suggests that AbdA, its cofactor Extradenticle (Exd), a helix-loop-helix transcription factor Grainyhead (Grh), and Notch signaling transcriptionally contribute to expression of RHG family of apoptotic genes. We find that Grh, AbdA, and Exd function together at multiple motifs on the apoptotic enhancer. In vivo mutagenesis of these motifs suggest that they are important for the maintenance of the activity of the enhancer rather than its initiation. We also find that Exd function is independent of its known partner homothorax in this apoptosis. We extend some of our findings to Deformed expressing region of sub-esophageal ganglia where pNBs undergo a similar Hox dependent apoptosis. We propose a mechanism where common players like Exd-Grh-Notch work with different Hox genes through region specific enhancers to pattern respective segments of larval central nervous system.

  10. Fas-induced apoptosis in malnourished infants

    African Journals Online (AJOL)

    EL-HAKIM

    regulation of the hematopoietic system6. Moreover, many studies have demonstrated that the apoptosis of immune cell in undernourished organisms may cause an increase in the organism's susceptibility to diseases related to immune suppression7,8,9. Lymphocyte apoptosis was described in peripheral blood and ...

  11. Apoptosis in mammalian oocytes: a review.

    Science.gov (United States)

    Tiwari, Meenakshi; Prasad, Shilpa; Tripathi, Anima; Pandey, Ashutosh N; Ali, Irfan; Singh, Arvind K; Shrivastav, Tulsidas G; Chaube, Shail K

    2015-08-01

    Apoptosis causes elimination of more than 99% of germ cells from cohort of ovary through follicular atresia. Less than 1% of germ cells, which are culminated in oocytes further undergo apoptosis during last phases of oogenesis and depletes ovarian reserve in most of the mammalian species including human. There are several players that induce apoptosis directly or indirectly in oocytes at various stages of meiotic cell cycle. Premature removal of encircling granulosa cells from immature oocytes, reduced levels of adenosine 3',5'-cyclic monophosphate and guanosine 3',5'-cyclic monophosphate, increased levels of calcium (Ca(2+)) and oxidants, sustained reduced level of maturation promoting factor, depletion of survival factors, nutrients and cell cycle proteins, reduced meiotic competency, increased levels of proapoptotic as well as apoptotic factors lead to oocyte apoptosis. The BH3-only proteins also act as key regulators of apoptosis in oocyte within the ovary. Both intrinsic (mitochondria-mediated) as well as extrinsic (cell surface death receptor-mediated) pathways are involved in oocyte apoptosis. BID, a BH3-only protein act as a bridge between both apoptotic pathways and its cleavage activates cell death machinery of both the pathways inside the follicular microenvironment. Oocyte apoptosis leads to the depletion of ovarian reserve that directly affects reproductive outcome of various mammals including human. In this review article, we highlight some of the important players and describe the pathways involved during oocyte apoptosis in mammals.

  12. Cortisol inhibits apoptosis in carp neutrophilic granulocytes.

    NARCIS (Netherlands)

    Weyts, F.A.A.; Flik, G.; Verburg-van Kemenade, B.M.L.

    1998-01-01

    The direct effect of cortisol treatment on carp neutrophil viability was examined in vitro. Cortisol treatment caused an inhibition of neutrophil apoptosis. The effect was blocked by glucocorticoid receptor blocker RU486, showing that rescue from apoptosis was receptor mediated. Using binding

  13. Crosstalk between apoptosis and inflammation in atherosclerosis

    NARCIS (Netherlands)

    Westra, Marijke Marianne

    2010-01-01

    In this thesis the role of several apoptosis regulating proteins in the development of atherosclerosis and atherosclerotic plaque stability is investigated. Apoptosis of different cell types in atherosclerotic plaques, such as macrophages and smooth muscle cells may inhibit or promote plaque

  14. Targeted induction of apoptosis for cancer therapy

    NARCIS (Netherlands)

    Bremer, Edwin

    2006-01-01

    Introduction to the thesis Programmed cell death, known as apoptosis, is an essential cellular homeostasis mechanism that ensures correct development and function of multi-cellular organisms. The pivotal importance of correct execution of apoptosis is apparent from the many human diseases with

  15. Reactive Oxygen Species, Apoptosis, Antimicrobial Peptides and Human Inflammatory Diseases

    Directory of Open Access Journals (Sweden)

    Babatunji Emmanuel Oyinloye

    2015-04-01

    Full Text Available Excessive free radical generation, especially reactive oxygen species (ROS leading to oxidative stress in the biological system, has been implicated in the pathogenesis and pathological conditions associated with diverse human inflammatory diseases (HIDs. Although inflammation which is considered advantageous is a defensive mechanism in response to xenobiotics and foreign pathogen; as a result of cellular damage arising from oxidative stress, if uncontrolled, it may degenerate to chronic inflammation when the ROS levels exceed the antioxidant capacity. Therefore, in the normal resolution of inflammatory reactions, apoptosis is acknowledged to play a crucial role, while on the other hand, dysregulation in the induction of apoptosis by enhanced ROS production could also result in excessive apoptosis identified in the pathogenesis of HIDs. Apparently, a careful balance must be maintained in this complex environment. Antimicrobial peptides (AMPs have been proposed in this review as an excellent candidate capable of playing prominent roles in maintaining this balance. Consequently, in novel drug design for the treatment and management of HIDs, AMPs are promising candidates owing to their size and multidimensional properties as well as their wide spectrum of activities and indications of reduced rate of resistance.

  16. Autophagy and apoptosis: where do they meet?

    Science.gov (United States)

    Mukhopadhyay, Subhadip; Panda, Prashanta Kumar; Sinha, Niharika; Das, Durgesh Nandini; Bhutia, Sujit Kumar

    2014-04-01

    Autophagy and apoptosis are two important cellular processes with complex and intersecting protein networks; as such, they have been the subjects of intense investigation. Recent advances have elucidated the key players and their molecular circuitry. For instance, the discovery of Beclin-1's interacting partners has resulted in the identification of Bcl-2 as a central regulator of autophagy and apoptosis, which functions by interacting with both Beclin-1 and Bax/Bak respectively. When localized to the endoplasmic reticulum and mitochondria, Bcl-2 inhibits autophagy. Cellular stress causes the displacement of Bcl-2 from Beclin-1 and Bax, thereby triggering autophagy and apoptosis, respectively. The induction of autophagy or apoptosis results in disruption of complexes by BH3-only proteins and through post-translational modification. The mechanisms linking autophagy and apoptosis are not fully defined; however, recent discoveries have revealed that several apoptotic proteins (e.g., PUMA, Noxa, Nix, Bax, XIAP, and Bim) modulate autophagy. Moreover, autophagic proteins that control nucleation and elongation regulate intrinsic apoptosis through calpain- and caspase-mediated cleavage of autophagy-related proteins, which switches the cellular program from autophagy to apoptosis. Similarly, several autophagic proteins are implicated in extrinsic apoptosis. This highlights a dual cellular role for autophagy. On one hand, autophagy degrades damaged mitochondria and caspases, and on the other hand, it provides a membrane-based intracellular platform for caspase processing in the regulation of apoptosis. In this review, we highlight the crucial factors governing the crosstalk between autophagy and apoptosis and describe the mechanisms controlling cell survival and cell death.

  17. Paclitaxel Induces Apoptosis in Breast Cancer Cells through Different Calcium—Regulating Mechanisms Depending on External Calcium Conditions

    Directory of Open Access Journals (Sweden)

    Zhi Pan

    2014-02-01

    Full Text Available Previously, we reported that endoplasmic reticulum calcium stores were a direct target for paclitaxel initiation of apoptosis. Furthermore, the actions of paclitaxel attenuated Bcl-2 resistance to apoptosis through endoplasmic reticulum-mediated calcium release. To better understand the calcium-regulated mechanisms of paclitaxel-induced apoptosis in breast cancer cells, we investigated the role of extracellular calcium, specifically; whether influx of extracellular calcium contributed to and/or was necessary for paclitaxel-induced apoptosis. Our results demonstrated that paclitaxel induced extracellular calcium influx. This mobilization of extracellular calcium contributed to subsequent cytosolic calcium elevation differently, depending on dosage. Under normal extracellular calcium conditions, high dose paclitaxel induced apoptosis-promoting calcium influx, which did not occur in calcium-free conditions. In the absence of extracellular calcium an “Enhanced Calcium Efflux” mechanism in which high dose paclitaxel stimulated calcium efflux immediately, leading to dramatic cytosolic calcium decrease, was observed. In the absence of extracellular calcium, high dose paclitaxel’s stimulatory effects on capacitative calcium entry and apoptosis could not be completely restored. Thus, normal extracellular calcium concentrations are critical for high dose paclitaxel-induced apoptosis. In contrast, low dose paclitaxel mirrored controls, indicating that it occurs independent of extracellular calcium. Thus, extracellular calcium conditions only affect efficacy of high dose paclitaxel-induced apoptosis.

  18. The promise of cancer therapeutics targeting the TNF-related apoptosis-inducing ligand and TRAIL receptor pathway.

    Science.gov (United States)

    Wang, S

    2008-10-20

    Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) is a member of the TNF superfamily and has been shown to induce apoptosis in cancer cells but not normal cells. TRAIL triggers apoptosis through binding to its receptors DR4 and KILLER/DR5. Chemo or radiotherapy induces apoptosis through activation of p53 in response to cellular damage, whereas TRAIL induces apoptosis independent of p53. Mutations or deletions of p53 occurred in more than half of human tumors confer resistance to chemo-radiotherapy. Treatment of TRAIL-resistant tumors with agents targeting death receptors, intrinsic Bcl-2 family members, inhibitor of apoptosis proteins or PI3K/Akt pathway restores the sensitivity to TRAIL-induced apoptosis. Combination of rhTRAIL or the agonist antibody for TRAIL receptor with conventional chemotherapeutic agents results in enhanced efficacy in preventing tumor progression and metastasis. Therefore, the rational design of TRAIL-based therapy combining with other modality that either synergizes to apoptosis induction or overcomes the resistance represents a challenging strategy to achieve the systemic tumor targeting and augment the antitumor activity of cancer therapeutics.

  19. Paclitaxel induces apoptosis in breast cancer cells through different calcium--regulating mechanisms depending on external calcium conditions.

    Science.gov (United States)

    Pan, Zhi; Avila, Andrew; Gollahon, Lauren

    2014-02-17

    Previously, we reported that endoplasmic reticulum calcium stores were a direct target for paclitaxel initiation of apoptosis. Furthermore, the actions of paclitaxel attenuated Bcl-2 resistance to apoptosis through endoplasmic reticulum-mediated calcium release. To better understand the calcium-regulated mechanisms of paclitaxel-induced apoptosis in breast cancer cells, we investigated the role of extracellular calcium, specifically; whether influx of extracellular calcium contributed to and/or was necessary for paclitaxel-induced apoptosis. Our results demonstrated that paclitaxel induced extracellular calcium influx. This mobilization of extracellular calcium contributed to subsequent cytosolic calcium elevation differently, depending on dosage. Under normal extracellular calcium conditions, high dose paclitaxel induced apoptosis-promoting calcium influx, which did not occur in calcium-free conditions. In the absence of extracellular calcium an "Enhanced Calcium Efflux" mechanism in which high dose paclitaxel stimulated calcium efflux immediately, leading to dramatic cytosolic calcium decrease, was observed. In the absence of extracellular calcium, high dose paclitaxel's stimulatory effects on capacitative calcium entry and apoptosis could not be completely restored. Thus, normal extracellular calcium concentrations are critical for high dose paclitaxel-induced apoptosis. In contrast, low dose paclitaxel mirrored controls, indicating that it occurs independent of extracellular calcium. Thus, extracellular calcium conditions only affect efficacy of high dose paclitaxel-induced apoptosis.

  20. Paclitaxel Induces Apoptosis in Breast Cancer Cells through Different Calcium—Regulating Mechanisms Depending on External Calcium Conditions

    Science.gov (United States)

    Pan, Zhi; Avila, Andrew; Gollahon, Lauren

    2014-01-01

    Previously, we reported that endoplasmic reticulum calcium stores were a direct target for paclitaxel initiation of apoptosis. Furthermore, the actions of paclitaxel attenuated Bcl-2 resistance to apoptosis through endoplasmic reticulum-mediated calcium release. To better understand the calcium-regulated mechanisms of paclitaxel-induced apoptosis in breast cancer cells, we investigated the role of extracellular calcium, specifically; whether influx of extracellular calcium contributed to and/or was necessary for paclitaxel-induced apoptosis. Our results demonstrated that paclitaxel induced extracellular calcium influx. This mobilization of extracellular calcium contributed to subsequent cytosolic calcium elevation differently, depending on dosage. Under normal extracellular calcium conditions, high dose paclitaxel induced apoptosis-promoting calcium influx, which did not occur in calcium-free conditions. In the absence of extracellular calcium an “Enhanced Calcium Efflux” mechanism in which high dose paclitaxel stimulated calcium efflux immediately, leading to dramatic cytosolic calcium decrease, was observed. In the absence of extracellular calcium, high dose paclitaxel’s stimulatory effects on capacitative calcium entry and apoptosis could not be completely restored. Thus, normal extracellular calcium concentrations are critical for high dose paclitaxel-induced apoptosis. In contrast, low dose paclitaxel mirrored controls, indicating that it occurs independent of extracellular calcium. Thus, extracellular calcium conditions only affect efficacy of high dose paclitaxel-induced apoptosis. PMID:24549172

  1. Sonodynamically induced apoptosis and active oxygen generation by gallium-porphyrin complex, ATX-70.

    Science.gov (United States)

    Yumita, Nagahiko; Okudaira, Kazuho; Momose, Yasunori; Umemura, Shin-Ichiro

    2010-11-01

    In this study, we investigated the induction of apoptosis by ultrasound in the presence of the photochemically active gallium-porphyrin complex, 7,12-bis(1-decyloxyethyl)-Ga(III)-3,8,13,17-tetramethyl-porphyrin 2,18-dipropionyl diaspartic acid (ATX-70). HL-60 cells were exposed to ultrasound for up to 3 min in the presence and absence of ATX-70, and the induction of apoptosis was examined by analyzing cell morphology, DNA fragmentation, and caspase-3 activity. Cells treated with 80 μM ATX-70 and ultrasound clearly showed membrane blebbing and cell shrinkage, whereas significant morphologic changes were not observed in cells exposed to either ultrasound or ATX-70 alone. Also, DNA ladder formation and caspase-3 activation were observed in cells treated with both ultrasound and ATX-70 but not in cells treated with ultrasound or ATX-70 alone. In addition, the combination of ATX-70 and the same acoustical arrangement of ultrasound substantially enhanced nitroxide generation by the cells. Sonodynamically induced apoptosis, caspase-3 activation, and nitroxide generation were significantly suppressed by histidine. These results indicate that the combination of ultrasound and ATX-70 induces apoptosis in HL-60 cells. The significant reduction in sonodynamically induced apoptosis, nitroxide generation, and caspase-3 activation by histidine suggests that active species such as singlet oxygen are important in the sonodynamic induction of apoptosis.

  2. Improvement of porcine cloning efficiency by trichostain A through early-stage induction of embryo apoptosis.

    Science.gov (United States)

    Ji, Qianqian; Zhu, Kongju; Liu, Zhiguo; Song, Zhenwei; Huang, Yuankai; Zhao, Haijing; Chen, Yaosheng; He, Zuyong; Mo, Delin; Cong, Peiqing

    2013-03-15

    Trichostain A (TSA), an inhibitor of histone deacetylases, improved developmental competence of SCNT embryos in many species, apparently by improved epigenetic reprogramming. The objective of the present study was to determine the effects of TSA-induced apoptosis in cloned porcine embryos. At various developmental stages, a comet assay and terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling staining were used to detect apoptosis, and real-time polymerase chain reaction was used to assess expression of genes related to apoptosis and pluripotency. In this study, TSA significantly induced apoptosis (in a dose-dependent manner) at the one-, two-, and four-cell stages. However, in blastocyst stage embryos, TSA decreased the apoptotic index (P < 0.05). Expression levels of Caspase 3 were higher in TSA-treated versus control embryos at the two-cell stage (not statistically significant). The expression ratio of antiapoptotic Bcl-xl gene to proapoptotic Bax gene, an indicator of antiapoptotic potential, was higher in TSA-treated groups at the one-, two-, and four-cell and blastocyst stages. Furthermore, expression levels of pluripotency-related genes, namely, Oct4 and Nanog, were elevated at the morula stage (P < 0.05) in TSA treatment groups. We concluded that inducing apoptosis might be a mechanism by which TSA promotes development of reconstructed embryos. At the initial stage of apoptosis induction, abnormal cells were removed, thereby enhancing proliferation of healthy cells and improving embryo quality. Copyright © 2013 Elsevier Inc. All rights reserved.

  3. Targeting Dynamin 2 as a Novel Pathway to Inhibit Cardiomyocyte Apoptosis Following Oxidative Stress.

    Science.gov (United States)

    Gao, Danchen; Yang, Jian; Wu, Yutao; Wang, Qiwen; Wang, Qiaoling; Lai, En Yin; Zhu, Jianhua

    2016-01-01

    Inhibition of Drp-1-mediated mitochondrial fission limits reactive oxygen species (ROS) production and apoptosis in cardiomyocytes subjected to ischemia/reperfusion injury. It remains unknown if Dynamin 2 inhibition results in similar protective effects. Here we studied the role of Dynamin 2 in cardiomyocyte oxidative stress-induced apoptosis and ROS production. The effect of lentiviral shRNA (lv5-shRNA) mediated Dynamin 2 knockdown on apopotosis, mitochondria, and ROS production were studied in neonatal mouse cardiomycytes, which were further treated with either selective Drp1 inhibitor mdivi-1 or the Dynamin 2/Drp1 inhibitor Dynasore. Apoptosis was evaluated by flow cytometry. Mitochondrial morphology and transmembrane potential (ΔΨm) were studied by confocal microscopy, and ROS production was detected by dichlorofluorescein diacetate. Inhibition of Drp1 and Dynamin 2 protected against mitochondrial fragmentation, maintained ΔΨm, attenuated cellular ROS production and limited apoptosis. Moreover, Lv5-shRNA mediated knockdown of Dynamin 2 alleviated mitochondrial fragmentation, and reduced both ROS production and oxidative stress-induced apoptosis. The protective effects of Dynamin 2 knockdown were enhanced by Dynasore, indicating an added benefit. Oxidative stress-induced apoptosis and ROS production are attenuated by not only Drp1 inhibition but also Dynamin 2 inhibition, implicating Dynamin 2 as a mediator of oxidative stress in cardiomyocytes. © 2016 The Author(s) Published by S. Karger AG, Basel.

  4. Porcine reproductive and respiratory syndrome virus induces apoptosis through a mitochondria-mediated pathway.

    Science.gov (United States)

    Lee, Sang-Myeong; Kleiboeker, Steven B

    2007-09-01

    As with a number of other viruses, Porcine reproductive and respiratory syndrome virus (PRRSV) has been shown to induce apoptosis, although the mechanism(s) involved remain unknown. In this study we have characterized the apoptotic pathways activated by PRRSV infection. PRRSV-infected cells showed evidence of apoptosis including phosphatidylserine exposure, chromatin condensation, DNA fragmentation, caspase activation (including caspase-8, 9, 3), and PARP cleavage. DNA fragmentation was dependent on caspase activation but blocking apoptosis by a caspase inhibitor did not affect PRRSV replication. Upregulation of Bax expression by PRRSV infection was followed by disruption of the mitochondria transmembrane potential, resulting in cytochrome c redistridution to the cytoplasm and subsequent caspase-9 activation. A crosstalk between the extrinsic and intrinsic pathways was demonstrated by dependency of caspase-9 activation on active caspase-8 and by Bid cleavage. Furthermore, in this study we provide evidence of the possible involvement of reactive oxygen species (ROS)-mediated oxidative stress in apoptosis induced by PRRSV. Our data indicated that cell death caused by PRRSV infection involves necrosis as well as apoptosis. In summary, these findings demonstrate mechanisms by which PRRSV induces apoptosis and will contribute to an enhanced understanding of PRRSV pathogenesis.

  5. The role of epithelial cell adhesion molecule N-glycosylation on apoptosis in breast cancer cells.

    Science.gov (United States)

    Zhang, Dandan; Liu, Xue; Gao, Jiujiao; Sun, Yan; Liu, Tingjiao; Yan, Qiu; Yang, Xuesong

    2017-03-01

    Glycosylation of cell surface proteins plays an important role in the regulation of apoptosis. It has been demonstrated that knockdown of epithelial cell adhesion molecule promoted apoptosis, inhibited cell proliferation, and caused cell-cycle arrest. In this study, we investigated whether and how N-glycosylation of epithelial cell adhesion molecule influenced the apoptosis in breast cancer cells. We applied the N-glycosylation mutation epithelial cell adhesion molecule plasmid to express deglycosylation of epithelial cell adhesion molecule and then to study its function. Our results showed that deglycosylation of epithelial cell adhesion molecule promoted apoptosis and inhibited cell proliferation. Deglycosylation of epithelial cell adhesion molecule enhanced the cytotoxic effect of 5-fluorouracil, promoting apoptosis by downregulating the expression of the anti-apoptotic protein Bcl-2 and upregulating the expression of the pro-apoptotic proteins Bax and Caspase 3 via the extracellular-signal-regulated kinase 1/2 and c-Jun N-terminal kinase mitogen-activated protein kinase signaling pathways in MCF-7 and MDA-MB-231 cells. These findings are important for a better understanding of epithelial cell adhesion molecule apoptosis regulation and suggest epithelial cell adhesion molecule as a potential target for the treatment of breast cancer.

  6. Nicotine Induces Podocyte Apoptosis through Increasing Oxidative Stress.

    Directory of Open Access Journals (Sweden)

    Xiqian Lan

    Full Text Available Cigarette smoking plays an important role in the progression of chronic kidney disease (CKD. Nicotine, one of the major components of cigarette smoking, has been demonstrated to increase proliferation of renal mesangial cells. In this study, we examined the effect of nicotine on podocyte injury.To determine the expression of nicotinic acetylcholine receptors (nAChR subunits in podocytes, cDNAs and cell lysate of cultured human podocytes were used for the expression of nAChR mRNAs and proteins, respectively; and mouse renal cortical sections were subjected to immunofluorescant staining. We also studied the effect of nicotine on podocyte nephrin expression, reactive oxygen species (ROS generation (via DCFDA loading followed by fluorometric analysis, proliferation, and apoptosis (morphologic assays. We evaluated the effect of nicotine on podocyte downstream signaling including phosphorylation of ERK1/2, JNK, and p38 and established causal relationships by using respective inhibitors. We used nAChR antagonists to confirm the role of nicotine on podocyte injury.Human podocytes displayed robust mRNA and protein expression of nAChR in vitro studies. In vivo studies, mice renal cortical sections revealed co-localization of nAChRs along with synaptopodin. In vitro studies, nephrin expression in podocyte was decreased by nicotine. Nicotine stimulated podocyte ROS generation; nonetheless, antioxidants such as N-acetyl cysteine (NAC and TEMPOL (superoxide dismutase mimetic agent inhibited this effect of nicotine. Nicotine did not modulate proliferation but promoted apoptosis in podocytes. Nicotine enhanced podocyte phosphorylation of ERK1/2, JNK, and p38, and their specific inhibitors attenuated nicotine-induced apoptosis. nAChR antagonists significantly suppressed the effects of nicotine on podocyte.Nicotine induces podocyte apoptosis through ROS generation and associated downstream MAPKs signaling. The present study provides insight into molecular

  7. Sun Ginseng Protects Endothelial Progenitor Cells From Senescence Associated Apoptosis

    Science.gov (United States)

    Im, Wooseok; Chung, Jin-Young; Bhan, Jaejun; Lim, Jiyeon; Lee, Soon-Tae; Chu, Kon; Kim, Manho

    2012-01-01

    Endothelial progenitor cells (EPC) are a population of cells that circulate in the blood stream. They play a role in angiogenesis and, therefore, can be prognostic markers of vascular repair. Ginsenoside Rg3 prevents endothelial cell apoptosis through the inhibition of the mitochondrial caspase pathway. It also affects estrogen activity, which reduces EPC senescence. Sun ginseng (SG), which is heat-processed ginseng, has a high content of ginsenosides. The purpose of this study was to investigate the protective effects of SG on senescence-associated apoptosis in EPCs. In order to isolate EPCs, mononuclear cells of human blood buffy coats were cultured and characterized by their uptake of acetylated low-density lipoprotein (acLDL) and their binding of Ulex europaeus agglutinin I (ulex-lectin). Flow cytometry with annexin-V staining was performed in order to assess early and late apoptosis. Senescence was determined by β-galactosidase (β-gal) staining. Staining with 4′-6-Diamidino-2-phenylindole verified that most adherent cells (93±2.7%) were acLDL-positive and ulex-lectin-positive. The percentage of β-gal-positive EPCs was decreased from 93.8±2.0% to 62.5±3.6% by SG treatment. A fluorescence-activated cell sorter (FACS) analysis showed that 4.9% of EPCs were late apoptotic in controls. Sun ginseng decreased the apoptotic cell population by 39% in the late stage of apoptosis from control baseline levels. In conclusion, these results show antisenescent and antiapoptotic effects of SG in human-derived EPCs, indicating that SG can enhance EPC-mediated repair mechanisms. PMID:23717107

  8. Functional analysis of molecular mechanisms of radiation induced apoptosis, that are not mediated by DNA damages; Funktionelle Analyse molekularer Mechanismen der strahleninduzierten Apoptose, die nicht ueber direkte DNA-Schaeden vermittelt werden

    Energy Technology Data Exchange (ETDEWEB)

    Angermeier, Marita; Moertl, Simone [Helmholtz Zentrum Muenchen, Neuherberg (Germany). Inst. fuer Strahlenbiologie

    2012-09-15

    The effects of low-dose irradiation pose new challenges on the radiation protection efforts. Enhanced cellular radiation sensitivity is displayed by disturbed cellular reactions and resulting damage like cell cycle arrest, DNA repair and apoptosis. Apoptosis serves as genetically determinate parameter for the individual radiation sensitivity. In the frame of the project the radiation-induced apoptosis was mechanistically investigated. Since ionizing radiation induced direct DNA damage and generates a reactive oxygen species, the main focus of the research was the differentiation and weighting of DNA damage mediated apoptosis and apoptosis caused by the reactive oxygen species (ROS).

  9. Differential susceptibility to hydrogen sulfide-induced apoptosis between PHLDA1-overexpressing oral cancer cell lines and oral keratinocytes: role of PHLDA1 as an apoptosis suppressor.

    Science.gov (United States)

    Murata, Takatoshi; Sato, Tsutomu; Kamoda, Takeshi; Moriyama, Hiromitsu; Kumazawa, Yasuo; Hanada, Nobuhiro

    2014-01-15

    Hydrogen sulfide (H2S) is a novel gasotransmitter that plays multiple biological roles in various body systems. In addition to its endogenous production, H2S is produced by bacteria colonizing digestive organs, including the oral cavity. H2S was previously shown to enhance pro-apoptotic effects in cancer cell lines, although the mechanisms involved remain unclear. To properly assess the anti-cancer effects of H2S, however, investigations of apoptotic effects in normal cells are also necessary. The aims of this study were (1) to compare the susceptibility to H2S-induced apoptosis between the oral cancer cell line Ca9-22 and oral keratinocytes that were derived from healthy gingiva, and (2) to identify candidate genes involved in the induction of apoptosis by H2S. The susceptibility to H2S-induced apoptosis in Ca9-22 cells was significantly higher than that in keratinocytes. H2S exposure in Ca9-22 cells, but not keratinocytes, enhanced the expression of pleckstrin homology-like domain, family A, member 1 (PHLDA1), which was identified through a differential display method. In addition, PHLDA1 expression increased during actinomycin D-induced apoptosis in Ca9-22 cells. Knockdown of PHLDA1 expression by small interfering RNA in Ca9-22 cells led to expression of active caspase 3, thus indicating apoptosis induction. The tongue cancer cell line SCC-25, which expresses PHLDA1 at a high level, showed similar effects. Our data indicate that H2S is an anti-cancer compound that may contribute to the low incidence of oral cancer. Furthermore, we demonstrated the role of PHLDA1 as an apoptosis suppressor. © 2013 Elsevier Inc. All rights reserved.

  10. Beclin-1-mediated autophagy protects spinal cord neurons against mechanical injury-induced apoptosis.

    Science.gov (United States)

    Wang, Zhen-Yu; Lin, Jian-Hua; Muharram, Akram; Liu, Wen-Ge

    2014-06-01

    Apoptosis has been widely reported to be involved in the pathogenesis associated with spinal cord injury (SCI). Recently, autophagy has also been implicated in various neuronal damage models. However, the role of autophagy in SCI is still controversial and its interrelationship with apoptosis remains unclear. Here, we used an in vitro SCI model to observe a time-dependent induction of autophagy and apoptosis. Mechanical injury induced autophagy markers such as LC3 lipidation, LC3II/LC3I conversion, and Beclin-1 expression. Injured neurons showed decreased cell viability and increased apoptosis. To elucidate the effect of autophagy on apoptosis, the mechanically-injured neurons were treated with the mTOR inhibitor rapamycin and 3-methyl adenine (3-MA), which are known to regulate autophagy positively and negatively, respectively. Rapamycin-treated neurons showed the highest level of cell viability and lowest level of apoptosis among the injured neurons and those treated with 3-MA showed the reciprocal effect. Notably, rapamycin-treated neurons exhibited slightly reduced Bax expression and significantly increased Bcl-2 expression. Furthermore, by plasmid transfection, we showed that Beclin-1-overexpressing neuronal cells responded to mechanical injury with greater LC3II/LC3I conversion and cell viability, lower levels of apoptosis, higher Bcl-2 expression, and unaltered Bax expression as compared to vector control cells. Beclin-1-knockdown neurons showed almost the opposite effects. Taken together, our results suggest that autophagy may serve as a protection against apoptosis in mechanically-injured spinal cord neurons. Targeting mTOR and/or enhancing Beclin-1 expression might be alternative therapeutic strategies for SCI.

  11. Advanced oxidation protein products induce chondrocyte apoptosis via receptor for advanced glycation end products-mediated, redox-dependent intrinsic apoptosis pathway.

    Science.gov (United States)

    Wu, Qian; Zhong, Zhao-Ming; Zhu, Si-Yuan; Liao, Cong-Rui; Pan, Ying; Zeng, Ji-Huan; Zheng, Shuai; Ding, Ruo-Ting; Lin, Qing-Song; Ye, Qing; Ye, Wen-Bin; Li, Wei; Chen, Jian-Ting

    2016-01-01

    Pro-inflammatory cytokine-induced chondrocyte apoptosis is a primary cause of cartilage destruction in the progression of rheumatoid arthritis (RA). Advanced oxidation protein products (AOPPs), a novel pro-inflammatory mediator, have been confirmed to accumulate in patients with RA. However, the effect of AOPPs accumulation on chondrocyte apoptosis and the associated cellular mechanisms remains unclear. The present study demonstrated that the plasma formation of AOPPs was enhanced in RA rats compared with normal. Then, chondrocyte were treated with AOPPs-modified rat serum albumin (AOPPs-RSA) in vitro. Exposure of chondrocyte to AOPPs activated nicotinamide adenine dinucleotide phosphate (NADPH) oxidase and increased expression of NADPH oxidase subunits, which was mediated by receptor for advanced glycation end products (RAGE), but not scavenger receptor CD36. Moreover, AOPPs challenge triggered NADPH oxidase-dependent ROS generation which induced mitochondrial dysfunction and endoplasmic reticulum stress resulted in activation of caspase family that eventually lead to apoptosis. Lastly, blockade of RAGE, instead of CD36, largely attenuated these signals. Our study demonstrated first time that AOPPs induce chondrocyte apoptosis via RAGE-mediated and redox-dependent intrinsic apoptosis pathway in vitro. These data implicates that AOPPs may represent a novel pathogenic factor that contributes to RA progression. Targeting AOPPs-triggered cellular mechanisms might emerge as a promising therapeutic option for patients with RA.

  12. Elevated pressure, a novel cancer therapeutic tool for sensitizing cisplatin-mediated apoptosis in A549

    Energy Technology Data Exchange (ETDEWEB)

    Oh, Sangnam [Cellular and Developmental Biology, Division of Biomedical Science, College of Medicine, Korea University, Seoul 136-705 (Korea, Republic of); Department of Preventive Medicine and Medical Research Center for Environmental Toxico-Genomics and Proteomics, College of Medicine, Korea University, Seoul 136-705 (Korea, Republic of); Kim, Yanghee [Department of Preventive Medicine and Medical Research Center for Environmental Toxico-Genomics and Proteomics, College of Medicine, Korea University, Seoul 136-705 (Korea, Republic of); Kim, Joonhee [Cellular and Developmental Biology, Division of Biomedical Science, College of Medicine, Korea University, Seoul 136-705 (Korea, Republic of); Department of Preventive Medicine and Medical Research Center for Environmental Toxico-Genomics and Proteomics, College of Medicine, Korea University, Seoul 136-705 (Korea, Republic of); Kwon, Daeho [Department of Preventive Medicine and Medical Research Center for Environmental Toxico-Genomics and Proteomics, College of Medicine, Korea University, Seoul 136-705 (Korea, Republic of); Lee, Eunil, E-mail: eunil@korea.ac.kr [Cellular and Developmental Biology, Division of Biomedical Science, College of Medicine, Korea University, Seoul 136-705 (Korea, Republic of); Department of Preventive Medicine and Medical Research Center for Environmental Toxico-Genomics and Proteomics, College of Medicine, Korea University, Seoul 136-705 (Korea, Republic of)

    2010-08-13

    Research highlights: {yields} Sensitized apoptosis in cancer cells stimulated by EP precondition with p53 dependence. {yields} EP attenuates several CDDP-resistance mechanisms. {yields} No harmful effect of EP on normal fibroblasts. -- Abstract: Intensive cancer therapy strategies have thus far focused on sensitizing cancer cells to anticancer drug-mediated apoptosis to overcome drug resistance, and this strategy has led to more effective cancer therapeutics. Cisplatin (cis-diamminedichloroplatinum(II), CDDP) is an effective anticancer drug used to treat many types of cancer, including non-small cell lung carcinoma (NSCLC), and can be used in combination with various chemicals to enhance cancer cell apoptosis. Here, we introduce the use of elevated pressure (EP) in combination with CDDP for cancer treatment and explore the effects of EP on CDDP-mediated apoptosis in NSCLC cells. Our findings demonstrate that preconditioning NSCLC cells with EP sensitizes cells for CDDP-induced apoptosis. Enhanced apoptosis was dependent on p53 and HO-1 expression, and was associated with increased DNA damage and down-regulation of genes involved in nucleotide excision repair. The transcriptional levels of transporter proteins indicated that the mechanism by which EP-induced CDDP sensitization was intracellular drug accumulation. The protein levels of some antioxidants, such as hemeoxygenase-1 (HO-1), glutathione (GSH) and glutathione peroxidase (Gpx), were decreased in A549 cells exposed to EP via the down-regulation of the transcription factor nuclear factor (erythroid-derived 2)-like 2 (Nrf-2). Furthermore, normal human fibroblasts were resistant to EP treatment, with no elevated DNA damage or apoptosis. Collectively, these data show that administration of EP is a potential adjuvant tool for CDDP-based chemosensitivity of lung cancer cells that may reduce drug resistance.

  13. Increased carnitine-dependent fatty acid uptake into mitochondria of human colon cancer cells induces apoptosis.

    Science.gov (United States)

    Wenzel, Uwe; Nickel, Alexander; Daniel, Hannelore

    2005-06-01

    Carnitine-dependent fatty acid import into mitochondria and beta-oxidation seem to be impaired in tumor cells. In the present study we show that a supply of palmitoylcarnitine together with L-carnitine potently induces apoptosis in HT-29 human colon cancer cells as a consequence of accelerated fatty acid oxidation. Caspase-3-like activities, measured by the cleavage rate of a fluorogenic tetrapeptide substrate and nuclear fragmentation determined after DNA labeling in fixed cells by fluorescence microscopy, served as indicators of apoptosis. Neither L-carnitine nor palmitoylcarnitine alone were able to increase caspase-3-like activities and DNA fragmentation, but when provided together, apoptosis occurred. That exogenous carnitine was indeed able to enhance fatty acid uptake into mitochondria was demonstrated by an increased influx of a fluorescent palmitic acid analog. Enhanced fatty acid availability in mitochondria led to an increased generation of O*2-, as detected by a O*2- -sensitive fluorogenic dye, indicating oxidation of delivered substrates. Benzoquinone, an O*2- scavenger, blocked O*2- generation and prevented apoptosis as initiated by the combination of palmitoylcarnitine and carnitine. The lack of effect of the ceramide synthesis inhibitor fumonisin on palmitoylcarnitine/carnitine-induced apoptosis further supports the notion that apoptotic cell death is specifically due to fatty acid oxidation. In contrast to HT-29 cells, nontransformed human colonocytes did not respond to exogenous palmitoylcarnitine/carnitine and no apoptosis was observed. In conclusion, our studies provide evidence that a limited mitochondrial fatty acid import in human colon cancer cells prevents high rates of mitochondrial O*2- production and protects colon cancer cells from apoptosis that can be overcome by an exogenous carnitine supply.

  14. Adrenomedullin Promotes the Proliferation and Inhibits Apoptosis of Dental Pulp Stem Cells Involved in Divergence Pathways.

    Science.gov (United States)

    Zhu, Qiang; Tian, Gang; Tang, Zhen; Gao, Jianyong; Tan, Yinghui

    2016-09-01

    Adrenomedullin (ADM) is highly expressed in dental tissues at the critical developmental time points during tooth development. However, its role in pulp repair and pulp injury is still unknown. The study aimed to investigate the mechanisms by which ADM affects the proliferation and apoptosis of human dental pulp stem cells (DPSCs). Fifty-four freshly extracted wisdom teeth were obtained from 27 patients with caries and 27 without. Enzyme-linked immunosorbent assay and immunohistochemistry were used to examine the expression levels of ADM in caries and normal pulp tissues. Human primary DPSCs from the third passage were incubated with ADM (10(-8) mol/L) for 24 hours; the cell cycle and apoptosis were investigated by flow cytomery, and protein expression was investigated using Western blot analysis. The levels of ADM in caries pulp tissues were significantly higher than those in normal pulp tissues. Incubation with ADM enhanced the percentage of G2/S/M phase DPSCs (P < .01) by the addition of a JNK/c-Jun inhibitor. Incubation with ADM reduced DPSC apoptosis by the addition of the Src/glycogen synthase kinase-3 inhibitor. ADM also ameliorated CoCl2-induced apoptosis and caspase-3 expression. ADM enhances the proliferation of DPSCs through activation of the JNK/c-Jun signaling pathway and inhibits apoptosis of DPSCs through activation of the Src/glycogen synthase kinase-3 signaling pathway. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  15. Aortic valvular interstitial cells apoptosis and calcification are mediated by TNF-related apoptosis-inducing ligand.

    Science.gov (United States)

    Galeone, Antonella; Brunetti, Giacomina; Oranger, Angela; Greco, Giovanni; Di Benedetto, Adriana; Mori, Giorgio; Colucci, Silvia; Zallone, Alberta; Paparella, Domenico; Grano, Maria

    2013-11-15

    Calcific aortic valvular disease (CAVD) is an actively regulated process characterized by the activation of specific osteogenic signaling pathways and apoptosis. We evaluated the involvement in CAVD of the TNF-related apoptosis-inducing ligand (TRAIL), an apoptotic molecule which induces apoptosis by interacting with the death receptor (DR)-4 and DR5, and whose activity is modulated by the decoy receptor (DcR)-1 and DcR2. Sections of calcific and normal aortic valves, obtained at surgery time, were subjected to immunohistochemistry and confocal microscopy for TRAIL immunostaining. Valvular interstitial cells (VICs) isolated from calcific (C-VICs) and normal (N-VICs) aortic valves were investigated for the gene and protein expression of TRAIL receptors. Cell viability was assayed by MTT. Von Kossa staining was performed to verify C-VIC ability to produce mineralized nodules. TRAIL serum levels were detected by ELISA. Higher levels of TRAIL were detected in calcific aortic valves and in sera from the same patients respect to controls. C-VICs express significantly higher mRNA and protein levels of DR4, DR5, DcR1, DcR2 and Runx2 compared to N-VICs. C-VICs and N-VICs, cultured in osteogenic medium, express significantly higher mRNA levels of DR4, Runx2 and Osteocalcin compared to baseline. C-VICs and N-VICs were sensitive to TRAIL-apoptotic effect at baseline and after osteogenic differentiation, as demonstrated by MTT assay and caspase-3 activation. TRAIL enhanced mineralized matrix nodule synthesis by C-VICs cultured in osteogenic medium. TRAIL is characteristically present within calcific aortic valves, and mediates the calcification of aortic valve interstitial cells in culture through mechanism involving apoptosis. © 2013.

  16. Resveratrol induces growth arrest and apoptosis through activation of FOXO transcription factors in prostate cancer cells.

    Directory of Open Access Journals (Sweden)

    Qinghe Chen

    2010-12-01

    Full Text Available Resveratrol, a naturally occurring phytopolyphenol compound, has attracted extensive interest in recent years because of its diverse pharmacological characteristics. Although resveratrol possesses chemopreventive properties against several cancers, the molecular mechanisms by which it inhibits cell growth and induces apoptosis have not been clearly understood. The present study was carried out to examine whether PI3K/AKT/FOXO pathway mediates the biological effects of resveratrol.Resveratrol inhibited the phosphorylation of PI3K, AKT and mTOR. Resveratrol, PI3K inhibitors (LY294002 and Wortmannin and AKT inhibitor alone slightly induced apoptosis in LNCaP cells. These inhibitors further enhanced the apoptosis-inducing potential of resveratrol. Overexpression of wild-type PTEN slightly induced apoptosis. Wild type PTEN and PTEN-G129E enhanced resveratrol-induced apoptosis, whereas PTEN-G129R had no effect on proapoptotic effects of resveratrol. Furthermore, apoptosis-inducing potential of resveratrol was enhanced by dominant negative AKT, and inhibited by wild-type AKT and constitutively active AKT. Resveratrol has no effect on the expression of FKHR, FKHRL1 and AFX genes. The inhibition of FOXO phosphorylation by resveratrol resulted in its nuclear translocation, DNA binding and transcriptional activity. The inhibition of PI3K/AKT pathway induced FOXO transcriptional activity resulting in induction of Bim, TRAIL, p27/KIP1, DR4 and DR5, and inhibition of cyclin D1. Similarly, resveratrol-induced FOXO transcriptional activity was further enhanced when activation of PI3K/AKT pathway was blocked. Over-expression of phosphorylation deficient mutants of FOXO proteins (FOXO1-TM, FOXO3A-TM and FOXO4-TM induced FOXO transcriptional activity, which was further enhanced by resveratrol. Inhibition of FOXO transcription factors by shRNA blocked resveratrol-induced upregulation of Bim, TRAIL, DR4, DR5, p27/KIP1 and apoptosis, and inhibition of cyclin D1 by

  17. Epigallocatechin gallate induces apoptosis of monocytes.

    Science.gov (United States)

    Kawai, Kazushige; Tsuno, Nelson H; Kitayama, Joji; Okaji, Yurai; Yazawa, Kentaro; Asakage, Masahiro; Sasaki, Shin; Watanabe, Toshiaki; Takahashi, Koki; Nagawa, Hirokazu

    2005-01-01

    Monocytes are the main effector cells of the immune system, and the regulation of their survival and apoptosis is essential for monocyte-involved immune responses. Green tea polyphenol catechin has been reported to have antiallergic and anti-inflammatory activities, but its effect on monocytes has not yet been explored. To elucidate the mechanisms of the anti-inflammatory effect of catechin, we studied the effect of catechin, especially epigallocatechin gallate (EGCG), on the apoptosis of monocytes. Isolated peripheral blood monocytes were incubated without or with catechin, and apoptosis was evaluated by annexin V and propidium iodide double-staining or terminal deoxynucleotidyl assay. The activation of caspases 3, 8, and 9 was also evaluated by flow cytometry. The influence of GM-CSF or LPS, the known monocyte survival factors, on the EGCG-induced apoptosis of monocytes was investigated. Among the 4 catechin derivatives tested, EGCG and epicatechin gallate induced apoptosis of monocytes. Caspases 3, 8, and 9, which play a central role in the apoptotic cascade, were dose-dependently activated by EGCG treatment. The EGCG-induced apoptosis of monocytes was not affected by GM-CSF or LPS. Catechin, especially EGCG, by promoting monocytic apoptosis, may be a new promising anti-inflammatory agent, and should be tested in clinical trials.

  18. Honey and Apoptosis in Human Gastric Mucosa

    Directory of Open Access Journals (Sweden)

    Alireza Ostadrahimi

    2012-07-01

    Full Text Available Background: Gastric cancer is the fourth most common malignancy in the world. Honey is acomplex mixture of special biological active constituents. Honey possesses antioxidant and antitumorproperties. Nutritional studies have indicated that consumption of honey modulates therisk of developing gastric cancer. On the other hand, apoptosis has been reported to play a decisiverole in precancerous changes. Our chief study was conducted to assess the relationship betweenconsumption of honey and apoptosis in human gastric mucosa.Method: This cross-sectional study was conducted on 98 subjects over 18 years old, referred totwo hospitals in Tabriz, Iran. Subjects were undergone an upper gastrointestinal endoscopy, 62subjects were finally enrolled. Honey consumption was assessed by a Food Frequency Questionnaire(FFQ and apoptosis was detected by TUNEL technique. We tested polynomial curve tofind the best fit between honey consumption and apoptosis.Results: A positive relation between honey consumption and apoptosis was found (P=0.024.Our results indicated that the final and the best fit curve was: apoptosis = 1.714+1.648(honeyamount - 0.533(honey amount2 +1.833×10-5(honey amount7.Conclusion: Honey consumption had positive effects on gastric cancer by inducing apoptosis ingastric mucosa.

  19. MicroRNA-1 promotes apoptosis of hepatocarcinoma cells by targeting apoptosis inhibitor-5 (API-5).

    Science.gov (United States)

    Li, Dong; Liu, Yu; Li, Hua; Peng, Jing-Jing; Tan, Yan; Zou, Qiang; Song, Xiao-Feng; Du, Min; Yang, Zheng-Hui; Tan, Yong; Zhou, Jin-Jun; Xu, Tao; Fu, Zeng-Qiang; Feng, Jian-Qiong; Cheng, Peng; chen, Tao; Wei, Dong; Su, Xiao-Mei; Liu, Huan-Yi; Qi, Zhong-Chun; Tang, Li-Jun; Wang, Tao; Guo, Xin; Hu, Yong-He; Zhang, Tao

    2015-01-02

    Although microRNA-1 (miR-1) is a known liver cancer suppressor, the role of miR-1 in apoptosis of hepatoma cells has remained largely unknown. Our study shows that ectopic miR-1 overexpression induced apoptosis of liver hepatocellular carcinoma (HepG2) cells. Apoptosis inhibitor 5 (API-5) was found to be a potential regulator of miR-1 induced apoptosis, using a bioinformatics approach. Furthermore, an inverse relationship between miR-1 and API-5 expression was observed in human liver cancer tissues and adjacent normal liver tissues. Negative regulation of API-5 expression by miR-1 was demonstrated to promote apoptosis of HepG2 cells. Our study provides a novel regulatory mechanism of miR-1 in the apoptosis of hepatoma cells. Copyright © 2014 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

  20. ClC-3 deficiency protects preadipocytes against apoptosis induced by palmitate in vitro and in type 2 diabetes mice.

    Science.gov (United States)

    Huang, Yun-Ying; Huang, Xiong-Qin; Zhao, Li-Yan; Sun, Fang-Yun; Chen, Wen-Liang; Du, Jie-Yi; Yuan, Feng; Li, Jie; Huang, Xue-Lian; Liu, Jie; Lv, Xiao-Fei; Guan, Yong-Yuan; Chen, Jian-Wen; Wang, Guan-Lei

    2014-11-01

    Palmitate, a common saturated free fatty acid (FFA), has been demonstrated to induce preadipocyte apoptosis in the absence of adipogenic stimuli, suggesting that preadipocytes may be prone to apoptosis under adipogenic insufficient conditions, like type 2 diabetes mellitus (T2DM). ClC-3, encoding Cl(-) channel or Cl(-)/H(+) antiporter, is critical for cell fate choices of proliferation versus apoptosis under diseased conditions. However, it is unknown whether ClC-3 is related with preadipocyte apoptosis induced by palmitate or T2DM. Palmitate, but not oleate, induced apoptosis and increase in ClC-3 protein expression and endoplasmic reticulum (ER) stress in 3T3-L1 preadipocyte. ClC-3 specific siRNA attenuated palmitate-induced apoptosis and increased protein levels of Grp78, ATF4, CHOP and phosphorylation of JNK1/2, whereas had no effects on increased phospho-PERK and phospho-eIF2α protein expression. Moreover, the enhanced apoptosis was shown in preadipocytes from high-sucrose/fat, low-dose STZ induced T2DM mouse model with hyperglycemia, hyperlipidemia (elevated serum TG and FFA levels) and insulin resistance. ClC-3 knockout significantly attenuated preadipocyte apoptosis and the above metabolic disorders in T2DM mice. These data demonstrated that ClC-3 deficiency prevent preadipocytes against palmitate-induced apoptosis via suppressing ER stress, and also suggested that ClC-3 may play a role in regulating cellular apoptosis and disorders of glucose and lipid metabolism during T2DM.

  1. EZH2 deletion promotes spermatogonial differentiation and apoptosis.

    Science.gov (United States)

    Jin, Cheng; Zhang, Yan; Wang, Zhi-Peng; Wang, Xiu-Xia; Sun, Tie-Cheng; Li, Xiao-Yu; Tang, Ji-Xin; Cheng, Jin-Mei; Li, Jian; Chen, Su-Ren; Deng, Shou-Long; Liu, Yi-Xun

    2017-11-01

    Spermatogenesis is crucial for male fertility and is therefore tightly controlled by a variety of epigenetic regulators. However, the function of enhancer of zeste homolog 2 (EZH2) in spermatogenesis and the molecular mechanisms underlying its activity remain poorly defined. Here, we demonstrate that deleting EZH2 promoted spermatogonial differentiation and apoptosis. EZH2 is expressed in spermatogonia, spermatocytes and round and elongated spermatids from stage 9 to 11 but not in leptotene and zygotene spermatocytes. Knocking down Ezh2 in vitro using a lentivirus impaired self-renewal in spermatogonial stem cells (SSCs), and the conditional knockout of Ezh2 in spermatogonial progenitors promoted precocious spermatogonial differentiation. EZH2 functions to balance self-renewal and differentiation in spermatogonia by suppressing NEUROG3 and KIT via a direct interaction that is independent of its histone methyltransferase activity. Moreover, deleting Ezh2 enhanced the activation of CASP3 in spermatids, resulting in reduced spermatozoa production. Collectively, these data demonstrate that EZH2 plays a nonclassical role in the regulation of spermatogonial differentiation and apoptosis in murine spermatogenesis. © 2017 Society for Reproduction and Fertility.

  2. Cell shrinkage as a signal to apoptosis in NIH 3T3 fibroblasts

    DEFF Research Database (Denmark)

    Friis, Martin B; Friborg, Christel R; Schneider, Linda

    2005-01-01

    Cell shrinkage is a hallmark of the apoptotic mode of programmed cell death, but it is as yet unclear whether a reduction in cell volume is a primary activation signal of apoptosis. Here we studied the effect of an acute elevation of osmolarity (NaCl or sucrose additions, final osmolarity 687...... mosmol l(-1)) on NIH 3T3 fibroblasts to identify components involved in the signal transduction from shrinkage to apoptosis. After 1.5 h the activity of caspase-3 started to increase followed after 3 h by the appearance of many apoptotic-like bodies. The caspase-3 activity increase was greatly enhanced...

  3. Apoptosis – is it good or bad?

    Directory of Open Access Journals (Sweden)

    Bakir Mehić

    2012-08-01

    Full Text Available The most widely used classification of mammalian cell death recognizes two types: apoptosis and necrosis. Autophagy, which has been proposed as a third mode of cell death allows a starving cell, or in situations when cell is deprived of growth factors, to survive. Apoptosis, autophagy and necrosis, a particular mode of cell death may predominate, depending of the injury and the type of cell. [1] One very important characteristic of all multicellular organisms is apoptosis, the controlled death of cells. In necrosis, early loss of integrity of the plasma membrane resultant with swelling of the cell and its organelles. A key morphologic feature of apoptosis is collapses of cell and its subcellular components.[2] The distinction between apoptosis and necrosis is due in part to differences in how the plasma membrane participates in these processes. In apoptosis, plasma membrane integrity persists until late in the process. In necrosis, early loss of integrity of the plasma membrane allows an influx of extracellular ions and fluid, with resultant swelling of the cell and its organelles. During that time, on the inside of cell there occurs the cleavage of cytoskeletal proteins by aspartate specific proteases, which thereby collapses subcellular components. Other characteristic features are chromatin condensation, nuclear fragmentation and the formation of plasma membrane blebs. The type and intensity of noxious signals, ATP concentration, cell type, and other factors determine how cell death occurs. Acute myocardial ischemia induces necrosis (because the ischemia precipitates rapid and profound decreases of ATP, whereas chronic congestive heart failure induces apoptosis (with more modest and chronic decreases of ATP. The blockade of a particular pathway of cell death may not prevent the destruction of the cell but may instead recruit an alternative path: antiapoptotic caspase inhibitors cause hyperacute necrosis of hepatocytes and kidney tubular cells

  4. Mitochondrial disfunction and apoptosis in leukemia cells

    Directory of Open Access Journals (Sweden)

    Annamaria PALLAG

    2008-05-01

    Full Text Available Apoptosis or programmed cell death is a process which involves the intentional degradation of the cell from the inside, the participation of the mitochondria to propagate the apoptotic signal, the alteration of the phospholipid cell membrane composition, the perturbation and alteration of the cell metabolism.The antineoplastic drugs is inducing the apoptotic process in the sensitive cells.It have been studied acute lymphoblastic leukemia cells. Using Annexin V-PE Apoptosis Detection Kit and flow cytometer, the amount of cells undergoing apoptosis, in various stages of the antineoplasic treatment, was detected. At the same time, were monitored, the serum level of malondialdehyde. The results obtained confirm the alteration of the mitochondrial metabolism. We can observed the mitochondrial dysfunction role in cell apoptosis.

  5. Liposomal Sphingolipids to Target Breast Adenocarcinoma Apoptosis

    National Research Council Canada - National Science Library

    Klostergaard, Jim

    2003-01-01

    We have observed that certain sphingolipids (e.g., dimethyl-sphingosine: DMSP) induce apoptosis in vitro in tumor cells despite the over-expression of HER-2/neu and other resistance mechanisms relevant to breast cancer...

  6. Molecular Analysis of Neurotoxin-Induced Apoptosis

    National Research Council Canada - National Science Library

    D'Mello, Santosh R

    2006-01-01

    Apoptosis is a cell-suicide process that is required for the normal development of the nervous system, but that can be aberrantly activated in neurodegenerative diseases and following exposure to neurotoxins...

  7. Apoptosis and Tumor Progressionin Prostate Cancer

    National Research Council Canada - National Science Library

    Tenniswood, Martin P

    2005-01-01

    ... (as measured by BrdU incorporation) and apoptosis as measured by TUNEL staining. We have standardized an efficient methodologies for isolating cells from primary tumors expressing REP by fluorescence activated cell sorting (FACS...

  8. Membranes as Sensitive Targets in Thymocyte Apoptosis

    Science.gov (United States)

    1993-01-01

    characterized by a Abstract. The role of cellular mronbranes in thymocyte generalized breakdown of cellular structure and apoptosis has been examined. Trolox , a...when added to called cellular suicide or programmed cell death cells within 30min post-irradiation. Exposure to trolox only (Kerr el at. 1972). during...chemical changes have been described in apoptosis, generated during radiation exposure. Incubation of the irra- diated cell suspension with trolox

  9. Apoptosis in amphibian organs during metamorphosis

    Science.gov (United States)

    Ishizuya-Oka, Atsuko; Hasebe, Takashi; Shi, Yun-Bo

    2012-01-01

    During amphibian metamorphosis, the larval tissues/organs rapidly degenerate to adapt from the aquatic to the terrestrial life. At the cellular level, a large quantity of apoptosis occurs in a spatiotemporally-regulated fashion in different organs to ensure timely removal of larval organs/tissues and the development of adult ones for the survival of the individuals. Thus, amphibian metamorphosis provides us a good opportunity to understand the mechanisms regulating apoptosis. To investigate this process at the molecular level, a number of thyroid hormone (TH) response genes have been isolated from several organs of Xenopus laevis tadpoles and their expression and functional analyses are now in progress using modern molecular and genetic technologies. In this review, we will first summarize when and where apoptosis occurs in typical larva-specific and larval-to-adult remodeling amphibian organs to highlight that the timing of apoptosis is different in different tissues/organs, even though all are induced by the same circulating TH. Next, to discuss how TH spatiotemporally regulates the apoptosis, we will focus on apoptosis of the X. laevis small intestine, one of the best characterized remodeling organs. Functional studies of TH response genes using transgenic frogs and culture techniques have shown that apoptosis of larval epithelial cells can be induced by TH either cell-autonomously or indirectly through interactions with extracellular matrix (ECM) components of the underlying basal lamina. Here, we propose that multiple intra- and extracellular apoptotic pathways are coordinately controlled by TH to ensure massive but well-organized apoptosis, which is essential for the proper progression of amphibian metamorphosis. PMID:20238476

  10. Effect of sevoflurane on human neutrophil apoptosis.

    LENUS (Irish Health Repository)

    Tyther, R

    2012-02-03

    BACKGROUND AND OBJECTIVE: Both chronic occupational exposure to volatile anaesthetic agents and acute in vitro exposure of neutrophils to isoflurane have been shown to inhibit the rate of apoptosis of human neutrophils. It is possible that inhibition of neutrophil apoptosis arises through delaying mitochondrial membrane potential collapse. We assessed mitochondrial depolarization and apoptosis in unexposed neutrophils and neutrophils exposed to sevoflurane in vivo. METHODS: A total of 20 mL venous blood was withdrawn pre- and postinduction of anaesthesia, the neutrophils isolated and maintained in culture. At 1, 12 and 24 h in culture, the percentage of neutrophil apoptosis was assessed by dual staining with annexin V-FITC and propidium iodide. Mitochondrial depolarization was measured using the dual emission styryl dye JC-1. RESULTS: Apoptosis was significantly inhibited in neutrophils exposed to sevoflurane in vivo at 24 (exposed: 38 (12)% versus control: 28 (11)%, P = 0.001), but not at 1 or 12 h, in culture. Mitochondrial depolarization was not delayed in neutrophils exposed to sevoflurane. CONCLUSIONS: The most important findings are that sevoflurane inhibits neutrophil apoptosis in vivo and that inhibition is not mediated primarily by an effect on mitochondrial depolarization.

  11. Molecular Mechanism of Apoptosis and Necrosis

    Directory of Open Access Journals (Sweden)

    Gulfidan Coskun

    2011-06-01

    Full Text Available Organismal homeostasis depends on an intricate balance between cell death and renewal. Apoptosis is a process of programmed cell death that plays a critical role in some normal and pathologic conditions beginning from embryologic development and ends at death. Apoptosis is initiated by morphological changes at the cell membrane, surface organels and nucleus. Apoptosis starts with death signals coming from outside or inside of the cell and continue to activate the mechanisms of apoptosis via cell death receptor or mitochondrial pathways. During apoptosis a group proteases are activated which cause DNA fragmentation, cytoplasmic shrinkage and membrane blebbing. Apoptotic cells divide into apoptotic bodies and then these apoptotic bodies are removed from tissue by phagocytes and adjacent cells In contrast to the “programmed” nature of apoptosis, necrotic cell death has always been believed to be a random, uncontrolled process that leads to death of the cell. Also necrosis, which is an other type of cell death, came to be used to describe pathologic cell death which cause inflamation. [Archives Medical Review Journal 2011; 20(3.000: 145-158

  12. [Downregulation of HSP70 gene expression and apoptosis in human hepatocellular carcinoma SMMC-7721 cells induced by nimesulide in vitro].

    Science.gov (United States)

    Yin, Guo-zhi; Tu, Kang-sheng; Han, Shao-shan; Wang, Jun; Liu, Qing-guang; Yao, Ying-min

    2012-09-01

    To investigate the effect of nimesulide on cell apoptosis and possible mechanism in human hepatocellular carcinoma SMMC-7721 cells. SMMC-7721 cells were treated with nimesulide at different concentrations. Cell viability was assessed by MTT assay. Cell apoptosis rate was determined with flow cytometry. The cleavage activity of PARP and caspase-9 and the expression of HSP70 were evaluated using RT-PCR and Western blotting. The influence of HSP70 on cell apoptosis was observed using RNA interference silencing HSP70 expression. Nimesulide significantly inhibited cell growth in SMMC-7721 cells in a time- and concentration-dependent manner, and induced cell apoptosis in a concentration-dependent manner. Moreover, nimesulide promoted the cleavage of caspase-9 and PARP and inhibited the mRNA and protein expression of HSP70. Through the specific inhibition on HSP70 gene with siRNA, cell apoptosis increased, and the apoptosis was enhanced by the cleavage activity of caspase-9 and PARP. Nimesulide could inhibit cell growth and induce apoptosis in human hepatocellular carcinoma SMMC-7721 cells via the downregulation of HSP70.

  13. Triptolide-Mediated Apoptosis by Suppression of Focal Adhesion Kinase through Extrinsic and Intrinsic Pathways in Human Melanoma Cells

    Directory of Open Access Journals (Sweden)

    Haw-Young Kwon

    2013-01-01

    Full Text Available Triptolide (TPL has been shown to inhibit cell proliferation and induce apoptosis in various human cancer cells; however, the precise mechanism of apoptosis induced by TPL in human melanoma cells has not yet been elucidated. In this study, we investigated the precise mechanism underlying cytocidal effects of TPL on human melanoma cells. Treatment of human melanoma cells with TPL significantly inhibited cell growth and induced apoptosis, as evidenced by flow cytometry and annexin V-fluorescein isothiocyanate analyses. TPL increased the levels of Fas and Fas-associated death domain (FADD and induced cleavage of Bid by activation of caspase-8 and cytochrome c release from mitochondria to the cytosol, which resulted in activation of caspase-9 and caspase-3. Moreover, TPL-induced apoptosis in SK-MEL-2 cells was mediated through dephosphorylation of focal adhesion kinase (FAK and its cleavage by caspase-8-mediated caspase-3 activation via upregulation of Fas expression. We also found that TPL mediated the dissociation of receptor-interacting protein (RIP from FAK and enhanced the formation of RIP/Fas complex formation initiating cell death. In conclusion, our data firstly demonstrated that TPL induces apoptosis by both extrinsic and intrinsic apoptosis pathways in human melanoma cells and identified that RIP shuttles between Fas and FAK to mediate apoptosis.

  14. The interaction between HIV-1 Nef and adaptor protein-2 reduces Nef-mediated CD4+ T cell apoptosis.

    Science.gov (United States)

    Jacob, Rajesh Abraham; Johnson, Aaron L; Pawlak, Emily N; Dirk, Brennan S; Van Nynatten, Logan R; Haeryfar, S M Mansour; Dikeakos, Jimmy D

    2017-09-01

    Acquired Immune Deficiency Syndrome is characterized by a decline in CD4+ T cells. Here, we elucidated the mechanism underlying apoptosis in Human Immunodeficiency Virus-1 (HIV-1) infection by examining host apoptotic pathways hijacked by the HIV-1 Nef protein in the CD4+ T-cell line Sup-T1. Using a panel of Nef mutants unable to bind specific host proteins we uncovered that Nef generates pro- and anti-apoptotic signals. Apoptosis increased upon mutating the motifs involved in the interaction of Nef:AP-1 (NefM20A or NefEEEE62-65AAAA) or Nef:AP-2 (NefLL164/165AA), implying these interactions limit Nef-mediated apoptosis. In contrast, disrupting the Nef:PAK2 interaction motifs (NefH89A or NefF191A) reduced apoptosis. To validate further, apoptosis was measured after short-hairpin RNA knock-down of AP-1, AP-2 and PAK2. AP-2α depletion enhanced apoptosis, demonstrating that disrupting the Nef:AP-2α interaction limits Nef-mediated apoptosis. Collectively, we describe a mechanism by which HIV-1 regulates cell survival and demonstrate the consequence of interfering with Nef:host protein interactions. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. Developmental Apoptosis Mediates Entry and Positioning of Microglia in the Zebrafish Brain

    Directory of Open Access Journals (Sweden)

    Alessandra Maria Casano

    2016-07-01

    Full Text Available In the brain, neurons that fail to assemble into functional circuits are eliminated. Their clearance depends on microglia, immune cells that colonize the CNS during embryogenesis. Despite the importance of these cells in development and disease, the mechanisms that target and position microglia within the brain are unclear. Here we show that, in zebrafish, attraction of microglia into the brain exploits differences in developmental neuronal apoptosis and that these provide a mechanism for microglial distribution. Reducing neuronal cell death results in fewer microglia, whereas increased apoptosis enhances brain colonization, resulting in more microglia at later stages. Interestingly, attraction into the brain depends on nucleotide signaling, the same signaling system used to guide microglia toward brain injuries. Finally, this work uncovers a cell-non-autonomous role for developmental apoptosis. Classically considered a wasteful process, programmed cell death is exploited here to configure the immune-neuronal interface of the brain.

  16. Effect of Uncaria tomentosa Extract on Apoptosis Triggered by Oxaliplatin Exposure on HT29 Cells

    Directory of Open Access Journals (Sweden)

    Liliane Z. de Oliveira

    2014-01-01

    Full Text Available Background/Aim. The use of herbal products as a supplement to minimize the effects of chemotherapy for cancer treatment requires further attention with respect to the activity and toxicity of chemotherapy. Uncaria tomentosa extract, which contains oxindole alkaloids, is one of these herbal products. The objective of this study was to evaluate whether Uncaria tomentosa extract modulates apoptosis induced by chemotherapy exposure. Materials and Methods. Colorectal adenocarcinoma cells (HT29 cells were grown in the presence of oxaliplatin and/or Uncaria tomentosa extract. Results. The hydroalcoholic extract of Uncaria tomentosa enhanced chemotherapy-induced apoptosis, with an increase in the percentage of Annexin positive cells, an increase in caspase activities, and an increase of DNA fragments in culture of the neoplastic cells. Moreover, antioxidant activity may be related to apoptosis. Conclusion. Uncaria tomentosa extract has a role for cancer patients as a complementary therapy. Further studies evaluating these beneficial effects with other chemotherapy drugs are recommended.

  17. Antioxidant micronutrients improve intrinsic and UV-induced apoptosis of human lymphocytes particularly in elderly people.

    Science.gov (United States)

    Ma, A G; Ge, S; Zhang, M; Shi, X X; Schouten, E G; Kok, F J; Sun, Y Y; Han, X X

    2011-12-01

    Aging and oxidative stress may lead to enhanced cellular damage and programmed cell death. To study the association of intrinsic apoptosis with age and the effect of antioxidant supplementation on intrinsic and UV-induced apoptosis in children, young and elderly people. The study was a 2 months, double-blind, randomized trial. Three age groups were studied: children, young adults and elderly people. A total of 274 healthy subjects were allocated to a group supplemented with moderate amounts of retinol, β-carotene, α-tocopherol, ascorbic acid and selenium or placebo. Plasma oxidative stress parameters were detected and apoptosis of lymphocytes was evaluated with TUNEL staining. At baseline, percentages of intrinsic apoptosis were 13.8% and 11.1% in elderly and young people, respectively, both significantly higher than children (6.3%). A decrease of 1.7% and 2.3% in intrinsic apoptosis of lymphocytes was found in the supplemented groups of young and elderly people compared with their control groups (all p values children. Moreover, percentages UV-induced apoptosis significantly decreased by 1.4%, 1.9% and 3.1% in children, young and elderly people, respectively, compared with control groups after the trial. There were considerable increments in concentrations of plasma β-carotene, retinol, tocopherol, ascorbic acid and selenium in all three treated groups after the supplementation. Young and elderly people have a higher intrinsic apoptosis than children, which was improved by antioxidant supplementation. UV-induced damage was attenuated by the supplementation in all three age groups.

  18. Activation of extrinsic apoptosis pathway in HCV monoinfected and HIV-HCV coinfected patients, irrespective of liver disease severity.

    Science.gov (United States)

    Feuth, Thijs; Van Baarle, Debbie; Hoepelman, Andy I M; Van Erpecum, Karel J; Siersema, Peter D; Arends, Joop E

    2014-07-01

    Chronic hepatitis C virus (HCV) infection is associated with increased levels of peripheral T cell apoptosis. We aimed to study whether T cell apoptosis markers indicate pathways that may contribute to clinical progression in HCV monoinfected and HIV-HCV coinfected patients. Activation of the extrinsic apoptosis pathways was measured by levels of death receptor Fas, initiator caspase 8 and effector caspases 3 and 7 activity and Annexin V binding on peripheral CD4 and CD8 T cells of HCV monoinfected and HIV/HCV coinfected patients, as well as healthy controls and HIV-infected, hepatitis B virus-infected and primary biliary cirrhosis disease controls. Association with liver fibrosis was assessed by biopsy or by transient elastography. HCV monoinfected and HIV-HCV coinfected patients displayed enhanced peripheral CD4 and CD8 T cell apoptosis. Caspase 8 activity was highest in HIV-HCV coinfection, without enhanced downstream activity of caspases 3 and 7. Level of peripheral T cell apoptosis was independent of liver fibrosis or other disease parameters in all disease groups. The extrinsic apoptosis pathway is upregulated in HCV monoinfection and HIV-HCV coinfection, but this is independent of liver disease severity.

  19. LINGO-1 Receptor Promotes Neuronal Apoptosis by Inhibiting WNK3 Kinase Activity*

    Science.gov (United States)

    Zhang, Zhaohuan; Xu, Xiaohui; Xiang, Zhenghua; Yu, Zhongwang; Feng, Jifeng; He, Cheng

    2013-01-01

    LINGO-1 is a functional component of the Nogo receptor 1·p75NTR·LINGO-1 and Nogo receptor 1·TAJ (TNFRSF19/TROY)·LINGO-1 signaling complexes. It has recently been shown that LINGO-1 antagonists significantly improve neuronal survival after neural injury. However, the mechanism by which LINGO-1 signaling influences susceptibility to apoptosis remains unknown. In an effort to better understand how LINGO-1 regulates these signaling pathways, we used an established model of serum deprivation (SD) to induce neuronal apoptosis. We demonstrate that treatment either with a construct containing the intracellular domain of LINGO-1 or with Nogo66, a LINGO-1 receptor complex agonist, resulted in an enhanced rate of apoptosis in primary cultured cortical neurons under SD. Reducing the expression levels of the serine/threonine kinase WNK3 using shRNA or inhibiting its kinase activity had similar effects on the survival of serum-deprived neurons. Consistent with these observations, we found that LINGO-1 and WNK3 co-localized and co-precipitated in cultured cortical neurons and brain tissue. Significantly, this co-association was enhanced by Nogo66 treatment. Binding of WNK3 to the intracellular domain of LINGO-1 led to a reduction in WNK3 kinase activity, as did Nogo66 stimulation. Moreover, in vitro and in vivo evidence indicates that endogenous WNK3 suppresses SD-induced neuronal apoptosis in a kinase-dependent manner, as the expression of either a WNK3 RNAi construct or a kinase-dead N-terminal fragment of WNK3 led to increased apoptosis. Taken together, our results show that LINGO-1 potentiates neuronal apoptosis, likely by inhibiting WNK3 kinase activity. PMID:23482566

  20. LINGO-1 receptor promotes neuronal apoptosis by inhibiting WNK3 kinase activity.

    Science.gov (United States)

    Zhang, Zhaohuan; Xu, Xiaohui; Xiang, Zhenghua; Yu, Zhongwang; Feng, Jifeng; He, Cheng

    2013-04-26

    LINGO-1 is a functional component of the Nogo receptor 1 · p75(NTR) · LINGO-1 and Nogo receptor 1 · TAJ (TNFRSF19/TROY)·LINGO-1 signaling complexes. It has recently been shown that LINGO-1 antagonists significantly improve neuronal survival after neural injury. However, the mechanism by which LINGO-1 signaling influences susceptibility to apoptosis remains unknown. In an effort to better understand how LINGO-1 regulates these signaling pathways, we used an established model of serum deprivation (SD) to induce neuronal apoptosis. We demonstrate that treatment either with a construct containing the intracellular domain of LINGO-1 or with Nogo66, a LINGO-1 receptor complex agonist, resulted in an enhanced rate of apoptosis in primary cultured cortical neurons under SD. Reducing the expression levels of the serine/threonine kinase WNK3 using shRNA or inhibiting its kinase activity had similar effects on the survival of serum-deprived neurons. Consistent with these observations, we found that LINGO-1 and WNK3 co-localized and co-precipitated in cultured cortical neurons and brain tissue. Significantly, this co-association was enhanced by Nogo66 treatment. Binding of WNK3 to the intracellular domain of LINGO-1 led to a reduction in WNK3 kinase activity, as did Nogo66 stimulation. Moreover, in vitro and in vivo evidence indicates that endogenous WNK3 suppresses SD-induced neuronal apoptosis in a kinase-dependent manner, as the expression of either a WNK3 RNAi construct or a kinase-dead N-terminal fragment of WNK3 led to increased apoptosis. Taken together, our results show that LINGO-1 potentiates neuronal apoptosis, likely by inhibiting WNK3 kinase activity.

  1. Chondrocyte Apoptosis in the Pathogenesis of Osteoarthritis

    Science.gov (United States)

    Hwang, Hyun Sook; Kim, Hyun Ah

    2015-01-01

    Apoptosis is a highly-regulated, active process of cell death involved in development, homeostasis and aging. Dysregulation of apoptosis leads to pathological states, such as cancer, developmental anomalies and degenerative diseases. Osteoarthritis (OA), the most common chronic joint disease in the elderly population, is characterized by progressive destruction of articular cartilage, resulting in significant disability. Because articular cartilage depends solely on its resident cells, the chondrocytes, for the maintenance of extracellular matrix, the compromising of chondrocyte function and survival would lead to the failure of the articular cartilage. The role of subchondral bone in the maintenance of proper cartilage matrix has been suggested as well, and it has been proposed that both articular cartilage and subchondral bone interact with each other in the maintenance of articular integrity and physiology. Some investigators include both articular cartilage and subchondral bone as targets for repairing joint degeneration. In late-stage OA, the cartilage becomes hypocellular, often accompanied by lacunar emptying, which has been considered as evidence that chondrocyte death is a central feature in OA progression. Apoptosis clearly occurs in osteoarthritic cartilage; however, the relative contribution of chondrocyte apoptosis in the pathogenesis of OA is difficult to evaluate, and contradictory reports exist on the rate of apoptotic chondrocytes in osteoarthritic cartilage. It is not clear whether chondrocyte apoptosis is the inducer of cartilage degeneration or a byproduct of cartilage destruction. Chondrocyte death and matrix loss may form a vicious cycle, with the progression of one aggravating the other, and the literature reveals that there is a definite correlation between the degree of cartilage damage and chondrocyte apoptosis. Because current treatments for OA act only on symptoms and do not prevent or cure OA, chondrocyte apoptosis would be a valid

  2. APOPTOSIS DURING HUMAN FETAL KIDNEY DEVELOPMENT

    Directory of Open Access Journals (Sweden)

    Rade Čukuranović

    2005-01-01

    Full Text Available Kidney morphogenesis is a complex and stepwise process. The formation of mature kidney in mammals is preceded by two primitive embryonic kidneys known as pronephros and mesonephros. Metanephros develops as a result of reciprocal inductive interactions between two primordial mesodermal derivates: ureteric bud, an epithelial outgrowth of the Wolffian duct, and metanephric blastema, a group of mesenchymal cells. The ureteric bud induces the metanephric mesenchyme to differentiate and form nephrons, whilst the metanephric mesenchyme induces the ureteric bud to grow and branch to form collecting ducts. The nephron goes through four developmental stages, which are described as: 1 vesicle, 2 comma-shaped and S-shaped stages, 3 developing capillary loop, and finally 4 maturing glomerulus. Apoptosis (programmed cell death is a predominant form of physiological cell death, by which organism eliminate unwanted or damaged cells. It is the major component of normal development and disease. Apoptosis is the result of series of biochemical processes happening in certain order in a dying cell, among which the most important is activation of enzyme families called caspases which influence different cell components. Apoptosis is characterized by membrane blebbing, shrinkage of the cell, nuclear fragmentation and chromatin condensation. Organelles are preserved almost intact. Cell surface molecules change. A variety of physiological and pathological stimuli can initiate apoptosis. They act via receptor mechanisms, through biochemical agents, or cause DNA and cell membrane damage. Apoptosis is an important component of fetal development. It is thought that apoptosis is the one of the main regulatory events involved in kidney morphogenesis, considering that among great number of developed cells, only a few of them are involved in the developing program by escaping apoptosis. In any period during kidney development about 3 to 5%of cells are apoptotic. Thorough

  3. Taraxerol Induces Cell Apoptosis through A Mitochondria-Mediated Pathway in HeLa Cells.

    Science.gov (United States)

    Yaoi, Xiangyang; Lu, Binyu; Lü, Chaotian; Bai, Qin; Yan, Dazhong; Xu, Hui

    2017-10-01

    Taraxerol acetate has potent anti-cancer effects via the induction of apoptosis, autophagy, cell cycle arrest, and inhibition of cell migration. However, whether taraxerol induced apoptosis and its underlying mechanisms of action is not clear. In the present study, we assess the effects of taraxerol on the mitochondrial apoptotic pathway and determine the release of cytochrome c to the cytosol and activation of caspases. In this experimental study, we mainly investigated the effect of taraxerol on HeLa cells. We tested cell viability by the MTT assay and morphologic changes, analyzed apoptosis by DAPI staining and flow cytometry. We also determined reactive oxygen species (ROS) and mitochondrial membrane potential (MMP) using a Microplate Reader. In addition, the apoptotic proteins were tested by Western blot. Taraxerol enhanced ROS levels and attenuated the MMP (Δψm) in HeLa cells. Taraxerol induced apoptosis mainly via the mitochondrial pathway including the release of cytochrome c to the cytosol and activation of caspases 9 and 3, and anti-poly (ADPribose) polymerase (PARP). Taraxerol could induce the down-regulation of the anti-apoptotic protein Bcl-2 and up-regulation of pro-apoptotic protein Bax. It suppressed the PI3K/ Akt signaling pathway. These results demonstrated that taraxerol induced cell apoptosis through a mitochondria-mediated pathway in HeLa cells. Thus, taraxerol might be a potential anticervical cancer candidate.

  4. Loss of runt-related transcription factor 3 expression leads hepatocellular carcinoma cells to escape apoptosis

    Directory of Open Access Journals (Sweden)

    Nakamura Shinichiro

    2011-01-01

    Full Text Available Abstract Background Runt-related transcription factor 3 (RUNX3 is known as a tumor suppressor gene for gastric cancer and other cancers, this gene may be involved in the development of hepatocellular carcinoma (HCC. Methods RUNX3 expression was analyzed by immunoblot and immunohistochemistry in HCC cells and tissues, respectively. Hep3B cells, lacking endogenous RUNX3, were introduced with RUNX3 constructs. Cell proliferation was measured using the MTT assay and apoptosis was evaluated using DAPI staining. Apoptosis signaling was assessed by immunoblot analysis. Results RUNX3 protein expression was frequently inactivated in the HCC cell lines (91% and tissues (90%. RUNX3 expression inhibited 90 ± 8% of cell growth at 72 h in serum starved Hep3B cells. Forty-eight hour serum starvation-induced apoptosis and the percentage of apoptotic cells reached 31 ± 4% and 4 ± 1% in RUNX3-expressing Hep3B and control cells, respectively. Apoptotic activity was increased by Bim expression and caspase-3 and caspase-9 activation. Conclusion RUNX3 expression enhanced serum starvation-induced apoptosis in HCC cell lines. RUNX3 is deleted or weakly expressed in HCC, which leads to tumorigenesis by escaping apoptosis.

  5. Treg cell resistance to apoptosis in DNA vaccination for experimental autoimmune encephalomyelitis treatment.

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    Youmin Kang

    Full Text Available BACKGROUND: Regulatory T (Treg cells can be induced with DNA vaccinations and protect mice from the development of experimental autoimmune encephalomyelitis (EAE, a mouse model of multiple sclerosis (MS. Tacrolimus (FK506 has been shown to have functions on inducing immunosuppression and augmenting apoptosis of pathologic T cells in autoimmune disease. Here we examined the therapeutic effect of DNA vaccine in conjunction with FK506 on EAE. METHODOLOGY/PRINCIPAL FINDINGS: After EAE induction, C57BL/6 mice were treated with DNA vaccine in conjunction with FK506. Functional Treg cells were induced in treated EAE mice and suppressed Th1 and Th17 cell responses. Infiltrated CD4 T cells were reduced while Treg cells were induced in spinal cords of treated EAE mice. Remarkably, the activated CD4 T cells augmented apoptosis, but the induced Treg cells resisted apoptosis in treated EAE mice, resulting in alleviation of clinical EAE severity. CONCLUSIONS/SIGNIFICANCE: DNA vaccine in conjunction with FK506 treatment ameliorates EAE by enhancing apoptosis of CD4 T cells and resisting apoptosis of induced Treg cells. Our findings implicate the potential of tolerogenic DNA vaccines for treating MS.

  6. N-Desmethyldauricine Induces Autophagic Cell Death in Apoptosis-Defective Cells via Ca(2+) Mobilization.

    Science.gov (United States)

    Law, Betty Y K; Mok, Simon W F; Chen, Juan; Michelangeli, Francesco; Jiang, Zhi-Hong; Han, Yu; Qu, Yuan Q; Qiu, Alena C L; Xu, Su-Wei; Xue, Wei-Wei; Yao, Xiao-Jun; Gao, Jia Y; Javed, Masood-Ul-Hassan; Coghi, Paolo; Liu, Liang; Wong, Vincent K W

    2017-01-01

    Resistance of cancer cells to chemotherapy remains a significant problem in oncology. Mechanisms regulating programmed cell death, including apoptosis, autophagy or necrosis, in the treatment of cancers have been extensively investigated over the last few decades. Autophagy is now emerging as an important pathway in regulating cell death or survival in cancer therapy. Recent studies demonstrated variety of natural small-molecules could induce autophagic cell death in apoptosis-resistant cancer cells, therefore, discovery of novel autophagic enhancers from natural products could be a promising strategy for treatment of chemotherapy-resistant cancer. By computational virtual docking analysis, biochemical assays, and advanced live-cell imaging techniques, we have identified N-desmethyldauricine (LP-4), isolated from rhizoma of Menispermum dauricum DC as a novel inducer of autophagy. LP-4 was shown to induce autophagy via the Ulk-1-PERK and Ca(2+)/Calmodulin-dependent protein kinase kinase β (CaMKKβ)-AMPK-mTOR signaling cascades, via mobilizing calcium release through inhibition of SERCA, and importantly, lead to autophagic cell death in a panel of cancer cells, apoptosis-defective and apoptosis-resistant cells. Taken together, this study provides detailed insights into the cytotoxic mechanism of a novel autophagic compound that targeting the apoptosis resistant cancer cells, and new implication on drug discovery from natural products for drug resistant cancer therapy.

  7. Immunomodulatory role of piperine in deltamethrin induced thymic apoptosis and altered immune functions.

    Science.gov (United States)

    Kumar, Anoop; Sasmal, D; Sharma, Neelima

    2015-03-01

    Deltamethrin (DLM), a well-known pyrethroid insecticide, is a potent immunotoxicant. In rodents, it is primarily characterized by marked thymic apoptosis. Mechanism of DLM induced thymic apoptosis in primary murine thymocytes has been recently explored. Oxidative stress and activation of caspase dependent pathways appear to be involved in the DLM induced thymic injury. Thus, for the amelioration of its effect, this study has been designed to first observe the binding affinity of piperine to immune cell receptors and its protective effects on the DLM induced immunotoxicity under in vitro condition. The docking results demonstrated that piperine has good binding affinity towards CD4 and CD8 receptors. In vitro study results have shown that piperine (1, 10 and 50 μg/ml) increased cell viability in a concentration dependent manner. The early activated markers of apoptosis such as enhanced reactive oxygen species (ROS) and caspase-3 activation by DLM was significantly reduced by piperine treatment. GSH depletion induced by DLM has been also restored by piperine treatment. At 18 h, all concentration of piperine (1, 10 and 50 μg/ml) significantly ameliorated the DLM induced apoptosis. Further, DLM induced phenotypic changes were mitigated by the piperine. In addition, piperine also restored the cytokine levels, which were suppressed by DLM treatment. These findings strongly indicate the anti-oxidative, anti-apoptotic and chemo-protective ability of piperine in the DLM induced thymic apoptosis. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. Oxidative Stress Induces Mouse Follicular Granulosa Cells Apoptosis via JNK/FoxO1 Pathway.

    Science.gov (United States)

    Weng, Qiannan; Liu, Zequn; Li, Bojiang; Liu, Kaiqing; Wu, Wangjun; Liu, Honglin

    2016-01-01

    The c-Jun N-terminal protein kinase (JNK) plays an important role in the regulation of cell apoptosis. Forkhead box O (FoxO) transcription factors are involved in diverse biological processes, including cellular metabolism, cell apoptosis, and cell cycle. However, the JNK/FoxO1 pathway involved in the process of apoptosis induced by oxidative stress remains to be elucidated. Here, we demonstrated that the JNK activity significantly increased in response to oxidative stress in mouse follicular granulosa cells (MGCs). SP600125, a selective JNK inhibitor, attenuated the oxidative stress-induced MGCs apoptosis. Oxidative stress enhanced the FoxO1 nuclear translocation by activating the JNK activity. Moreover, JNK mediated the dissociation of FoxO1 from 14-3-3 proteins in MGCs after the treatment with H2O2. Finally, oxidative stress up-regulated the expression of FoxO1 via JNK mediation of FoxO1 self-regulation in MGCs. Taken together, our findings suggest that JNK/FoxO1 is involved in the regulation of oxidative stress-induced cell apoptosis in MGCs.

  9. Glutamate-mediated protection of crayfish glial cells from PDT-induced apoptosis

    Science.gov (United States)

    Rudkovskii, M. V.; Romanenko, N. P.; Berezhnaya, E. V.; Kovaleva, V. D.; Uzdensky, A. B.

    2011-03-01

    Photodynamic treatment that causes intense oxidative stress and kills cells is currently used in neurooncology. However, along with tumor it damages surrounding healthy neurons and glial cells. In order to study the possible role of glutamate-related signaling pathways in photodynamic injury of neurons and glia, we investigated photodynamic effect of alumophthalocyanine Photosens on isolated crayfish stretch receptor that consists of a single neuron surrounded by glial cells. The laser diode (670 nm, 0.4 W/cm2) was used for dye photoexcitation. Application of glutamate increased photodynamically induced necrosis of neurons and glial cells but significantly decreased glial apoptosis. The natural neuroglial mediator N-acetylaspartylglutamate, which releases glutamate after cleavage in the extracellular space by glutamate carboxypeptidase II, also inhibited photoinduced apoptosis. Inhibition of glutamate carboxypeptidase II, oppositely, enhanced apoptosis of glial cells. These data confirm the anti-apoptotic activity of glutamate. Application of NMDA or inhibition of NMDA receptors by MK801 did not influence photodynamic death of neurons and glial cells that indicated nonparticipation of NMDA receptors in these processes. Inhibition of metabotropic glutamate receptors by AP-3 decreased PDT-induced apoptosis. One can suggest that crayfish neurons naturally secrete NAAG, which being cleaved by GCOP produces glutamate. Glutamate prevents photoinduced apoptosis of glial cells possibly through metabotropic but not ionotropic glutamate receptors.

  10. Macroautophagy-generated increase of lysosomal amyloid β-protein mediates oxidant-induced apoptosis of cultured neuroblastoma cells

    DEFF Research Database (Denmark)

    Zheng, Lin; Terman, Alexei; Hallbeck, Martin

    2011-01-01

    and accumulation of Aβ within lysosomes, induced apoptosis in differentiated SH-SY5Y neuroblastoma cells. Cells under hyperoxia showed: (1) increased numbers of autophagic vacuoles that contained amyloid precursor protein (APP) as well as Aβ monomers and oligomers, (2) increased reactive oxygen species production......, and (3) enhanced apoptosis. Oxidant-induced apoptosis positively correlated with cellular Aβ production, being the highest in cells that were stably transfected with APP Swedish KM670/671NL double mutation. Inhibition of γ-secretase, prior and/or in parallel to hyperoxia, suggested that the increase...... and resulting lysosomal Aβ accumulation are essential for oxidant-induced apoptosis in cultured neuroblastoma cells and provide additional support for the interactive role of oxidative stress and the lysosomal system in AD-related neurodegeneration....

  11. Simultaneous human papilloma virus type 16 E7 and cdk inhibitor p21 expression induces apoptosis and cathepsin B activation

    DEFF Research Database (Denmark)

    Kaznelson, Dorte Wissing; Bruun, Silas; Monrad, Astrid

    2004-01-01

    Human papillomavirus type 16 (HPV-16) is the major risk factor for development of cervical cancer. The major oncoprotein E7 enhances cell growth control. However, E7 has in some reports been shown to induce apoptosis suggesting that there is a delicate balance between cell proliferation and induc......Human papillomavirus type 16 (HPV-16) is the major risk factor for development of cervical cancer. The major oncoprotein E7 enhances cell growth control. However, E7 has in some reports been shown to induce apoptosis suggesting that there is a delicate balance between cell proliferation...

  12. MISC-1/OGC links mitochondrial metabolism, apoptosis and insulin secretion.

    Directory of Open Access Journals (Sweden)

    Marco Gallo

    Full Text Available We identified MISC-1 (Mitochondrial Solute Carrier as the C. elegans orthologue of mammalian OGC (2-oxoglutarate carrier. OGC was originally identified for its ability to transfer α-ketoglutarate across the inner mitochondrial membrane. However, we found that MISC-1 and OGC are not solely involved in metabolic control. Our data show that these orthologous proteins participate in phylogenetically conserved cellular processes, like control of mitochondrial morphology and induction of apoptosis. We show that MISC-1/OGC is required for proper mitochondrial fusion and fission events in both C. elegans and human cells. Transmission electron microscopy reveals that loss of MISC-1 results in a decreased number of mitochondrial cristae, which have a blebbed appearance. Furthermore, our pull-down experiments show that MISC-1 and OGC interact with the anti-apoptotic proteins CED-9 and Bcl-x(L, respectively, and with the pro-apoptotic protein ANT. Knock-down of misc-1 in C. elegans and OGC in mouse cells induces apoptosis through the caspase cascade. Genetic analysis suggests that MISC-1 controls apoptosis through the physiological pathway mediated by the LIN-35/Rb-like protein. We provide genetic and molecular evidence that absence of MISC-1 increases insulin secretion and enhances germline stem cell proliferation in C. elegans. Our study suggests that the mitochondrial metabolic protein MISC-1/OGC integrates metabolic, apoptotic and insulin secretion functions. We propose a novel mechanism by which mitochondria integrate metabolic and cell survival signals. Our data suggest that MISC-1/OGC functions by sensing the metabolic status of mitochondria and directly activate the apoptotic program when required. Our results suggest that controlling MISC-1/OGC function allows regulation of mitochondrial morphology and cell survival decisions by the metabolic needs of the cell.

  13. Apoptosis in chronic tonsillitis and tonsillar hypertrophy.

    Science.gov (United States)

    Önal, Merih; Yılmaz, Taner; Bilgiç, Elif; Müftüoğlu, Sevda Fatma; Kuşçu, Oğuz; Günaydın, Rıza Önder

    2015-02-01

    Chronic tonsillitis is the persistent inflammation of the tonsillar tissue that occurs due to recurrent, acute or subclinical infection. The recurrent and chronic inflammation of palatine tonsils sometimes results in hypertrophy. Apoptosis provides an important balance between lymphocytes in tonsillar lymphoid tissue. The aim of this study is to investigate the apoptosis in tonsillar diseases. 43 patients with chronic tonsilitis and tonsillar hypertrophy underwent tonsillectomy. The specimens were examined immunohistochemically for apoptosis. Tonsils were assembled into groups according to their size. Specimens were compared for their apoptotic cell count. The apoptosis difference between the tonsil size groups is not statistically significant (p>0.05). However, when the study group was divided into two at age 6, the difference was not statistically significant for patients at and below 6 years of age; but, the difference was statistically significant for patients above 6 years of age (ptonsil tissue (intrafollicular, interfollicular, subepithelial and intraepithelial) between tonsil size stages and between chronic tonsillitis and tonsillar hypertrophy groups revealed no statistical significance (p>0.05). There was a statistically significant positive correlation between intrafollicular and interfollicular, interfollicular and intraepithelial & subepithelial and intraepithelial areas (ptonsil tissue. The association of apoptosis with tonsillar hypertrophy seemed to be age-dependent. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  14. Sodium nitroprusside induces apoptosis of rabbit chondrocytes

    Science.gov (United States)

    Liang, Qian; Wang, Xiao-Ping; Chen, Tong-Sheng

    2013-02-01

    Osteoarthritis (OA) is characterized by a slowly progressing degradation of the matrix and destruction of articular cartilage. Apoptosis of chondrocyte is accounted for the mechanism of OA. Nitric oxide (NO), as a stimulus, has been shown to induce chondrocyte apoptosis by activating the matrix metalloproteinases (MMPs), increasing the expression of cyclooxygenase 2 (COX-2) and the level of prostaglandin E2 (PGE2), inhibiting the proteoglycan synthesis and type II collagen expression. In this study, sodium nitroprusside (SNP) was administered to be the NO donor to explore the mechanism of NO-induced apoptosis of rabbit chondrocytes obtained from six weeks old New Zealand rabbits. CCK-8 assay revealed the inhibitory effect of SNP on cell viability. We used flow cytometry (FCM) to assess the form of cell death by Annexin-V/propidium iodide (PI) double staining, and evaluate the change of mitochondrial membrane potential (ΔΨm). We found that the SNP induced chondrocyte apoptosis in a dose- and time-dependent manner and an observable reduction of ΔΨm. In conclusion, our findings indicate that SNP induces apoptosis of rabbit chondrocytes via a mitochondria-mediated pathway.

  15. The novel Akt inhibitor API-1 induces c-FLIP degradation and synergizes with TRAIL to augment apoptosis independent of Akt inhibition.

    Science.gov (United States)

    Li, Bo; Ren, Hui; Yue, Ping; Chen, Mingwei; Khuri, Fadlo R; Sun, Shi-Yong

    2012-04-01

    API-1 (pyrido[2,3-d]pyrimidines) is a novel small-molecule inhibitor of Akt, which acts by binding to Akt and preventing its membrane translocation and has promising preclinical antitumor activity. In this study, we reveal a novel function of API-1 in regulation of cellular FLICE-inhibitory protein (c-FLIP) levels and TRAIL-induced apoptosis, independent of Akt inhibition. API-1 effectively induced apoptosis in tested cancer cell lines including activation of caspase-8 and caspase-9. It reduced the levels of c-FLIP without increasing the expression of death receptor 4 (DR4) or DR5. Accordingly, it synergized with TRAIL to induce apoptosis. Enforced expression of ectopic c-FLIP did not attenuate API-1-induced apoptosis but inhibited its ability to enhance TRAIL-induced apoptosis. These data indicate that downregulation of c-FLIP mediates enhancement of TRAIL-induced apoptosis by API-1 but is not sufficient for API-1-induced apoptosis. API-1-induced reduction of c-FLIP could be blocked by the proteasome inhibitor MG132. Moreover, API-1 increased c-FLIP ubiquitination and decreased c-FLIP stability. These data together suggest that API-1 downregulates c-FLIP by facilitating its ubiquitination and proteasome-mediated degradation. Because other Akt inhibitors including API-2 and MK2206 had minimal effects on reducing c-FLIP and enhancement of TRAIL-induced apoptosis, it is likely that API-1 reduces c-FLIP and enhances TRAIL-induced apoptosis independent of its Akt-inhibitory activity. 2012 AACR

  16. Triticuside A, a dietary flavonoid, inhibits proliferation of human breast cancer cells via inducing apoptosis.

    Science.gov (United States)

    Shan, Yu; Cheng, Yan; Zhang, Yi; Guan, Fu-Qin; Sun, Hao; Ren, Xing-cong; Chen, Yu; Feng, Xu; Yang, Jin-Ming

    2013-01-01

    In this study we demonstrated that Triticuside A, one of the flavonoid compounds isolated from wheat bran, induced apoptosis and inhibited proliferation of human breast cancer cells. Triticuside A inhibited the proliferation of human breast cancer cells (MCF-7 and MDA-MB-231) in a dose-dependent manner but barely showed cytotoxicity to the normal human fibroblasts. Triticuside A-induced apoptosis was accompanied by a significant decrease of Mcl-1 and Bcl-2 proteins and by an increase of cleavage of caspases-3, -7, -9, and PARP. Triticuside A also suppressed the level of phospho-Akt and its downstream targets, mTOR and P70 S6 kinase. LY294002, a specific inhibitor of PI3K, significantly enhanced the Triticuside A-induced apoptosis. Moreover LY294002 not only downregulated the level of phospho-Akt but also enhanced the inhibition of Mcl-1 expression when combined with Triticuside A. Our results demonstrate for the first time the specific apoptogenic activity of Triticuside A in tumor cells and involvement of the mitochondrial apoptosis pathway and Akt/mTOR signaling pathway. Thus, Triticuside A may be a potentially useful wheat bran component that can be used for prevention or treatment of breast cancer.

  17. The role of Fas mediated apoptosis in preeclampsia.

    Science.gov (United States)

    Neale, Donna M; Mor, Gil

    2005-01-01

    It has become clear in recent years that apoptosis is a normal process in trophoblast turnover during pregnancy. Increased trophoblast apoptosis has been observed in the placenta of women with preeclampsia, serum from women with preeclampsia has been found to induce increased trophoblast sensitivity to Fas-mediated apoptosis, and serum from women with preeclampsia has elevated levels of various chemokines, growth factors and cytokines that are involved in the regulation of apoptosis. This review highlights the importance of apoptosis in normal placental development and explores the mechanisms whereby Fas-mediated apoptosis may play a role in conditions related to abnormal placentation, such as preeclampsia.

  18. Oxidative stress and apoptosis in preeclampsia.

    Science.gov (United States)

    Can, Murat; Guven, Berrak; Bektas, Sibel; Arikan, Ilker

    2014-12-01

    We aimed to determine the oxidative stress and antioxidant status in preeclamptic placenta. Also, we investigated the apoptotic index of villous trophoblast and proliferation index of cytotrophoblasts. The study included 32 pregnant with preeclampsia and 31 normotensive healthy pregnant women. Malondialdehyde (MDA) and total antioxidant status (TAS) levels were measured in the placenta. For detection of apoptosis and proliferation in trophoblast, apoptosis protease activating factor 1 (APAF-1) and Ki-67 were used. Placental MDA levels in preeclamptic women were significantly higher than normal pregnancies (p=0.002). There was no significant difference between the groups in the TAS levels of placenta (p=0.773). Also, the apoptotic index in villous trophoblasts increased (ppreeclampsia (p=0.850). Increased oxidative stress and apoptosis in pathological placenta are not balanced by antioxidant systems and proliferation mechanisms. Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. Apoptosis in Drosophila: which role for mitochondria?

    Science.gov (United States)

    Clavier, Amandine; Rincheval-Arnold, Aurore; Colin, Jessie; Mignotte, Bernard; Guénal, Isabelle

    2016-03-01

    It is now well established that the mitochondrion is a central regulator of mammalian cell apoptosis. However, the importance of this organelle in non-mammalian apoptosis has long been regarded as minor, mainly because of the absence of a crucial role for cytochrome c in caspase activation. Recent results indicate that the control of caspase activation and cell death in Drosophila occurs at the mitochondrial level. Numerous proteins, including RHG proteins and proteins of the Bcl-2 family that are key regulators of Drosophila apoptosis, constitutively or transiently localize in mitochondria. These proteins participate in the cell death process at different levels such as degradation of Diap1, a Drosophila IAP, production of mitochondrial reactive oxygen species or stimulation of the mitochondrial fission machinery. Here, we review these mitochondrial events that might have their counterpart in human.

  20. Death penalty for keratinocytes: apoptosis versus cornification.

    Science.gov (United States)

    Lippens, S; Denecker, G; Ovaere, P; Vandenabeele, P; Declercq, W

    2005-11-01

    Homeostasis implies a balance between cell growth and cell death. This balance is essential for the development and maintenance of multicellular organisms. Homeostasis is controlled by several mechanisms including apoptosis, a process by which cells condemned to death are completely eliminated. However, in some cases, total destruction and removal of dead cells is not desirable, as when they fulfil a specific function such as formation of the skin barrier provided by corneocytes, also known as terminally differentiated keratinocytes. In this case, programmed cell death results in accumulation of functional cell corpses. Previously, this process has been associated with apoptotic cell death. In this overview, we discuss differences and similarities in the molecular regulation of epidermal programmed cell death and apoptosis. We conclude that despite earlier confusion, apoptosis and cornification occur through distinct molecular pathways, and that possibly antiapoptotic mechanisms are implicated in the terminal differentiation of keratinocytes.

  1. Apoptosis: Therapeutic target in neurodegeneration and sepsis

    Directory of Open Access Journals (Sweden)

    Gonzalo Arboleda

    2005-12-01

    Full Text Available Cellular apoptosis has been considered as themain physiological mechanism underlyingneuronal demise associated to neurodegenerativediseases. Apoptosis has also been described inparenquimal and microvascular endotheliumin the acute phase of sepsis during multi-organicdysfunction. Therefore, strategies aimed toMuerte celular: blanco terapéutico enneurodegeneración y sepsisGonzalo Arboleda*, Luisa M. Matheus†prevent apoptosis (anti-apoptotic represent avaluable tool for prevention and/or retardationof the appearance of clinical symptoms in thesedisorders, which generate a large morbilitymortality,social and economic burden worldwide.The present review is aim to show that antiapoptoticstrategies hold a great therapeuticpotential. In this sense, we will review some ofthese potential therapies such as caspaseinhibitors, activated protein C, Bcl-2 family andthe PI3K/Akt signalling pathway.

  2. Stressed to death: implication of lymphocyte apoptosis for psychoneuroimmunology

    Science.gov (United States)

    Shi, Yufang; Devadas, Satish; Greeneltch, Kristy M.; Yin, Deling; Allan Mufson, R.; Zhou, Jian-nian

    2003-01-01

    Psychological and physical stressors best exemplify the intercommunication of the immune and the nervous systems. It has been shown that stress significantly impacts leukocyte cellularity and immune responses and alters susceptibility to various diseases. While acute stress has been shown to enhance immune responses, chronic stress often leads to immunosuppression. Among many criteria examined upon exposure to chronic stress, the reduction in lymphocyte mitogenic response and lymphocyte cellularity are commonly assessed. We have reported that chronic restraint stress could induce lymphocyte reduction, an effect dependent on endogenous opioids. Interestingly, the effect of endogenous opioids was found to be exerted through increasing the expression of a cell death receptor, Fas, and an increased sensitivity of lymphocytes to apoptosis. Stress-induced lymphocyte reduction was not affected by adrenalectomy. In this review, based on available literature and our recent data, we will discuss the role of the hypothalamic-pituitary-adrenal axis and endogenous opioids and examine the mechanisms by which chronic stress modulates lymphocyte apoptosis.

  3. Apoptosis and Necrosis in the Liver

    Science.gov (United States)

    Guicciardi, Maria Eugenia; Malhi, Harmeet; Mott, Justin L.; Gores, Gregory J.

    2013-01-01

    Because of its unique function and anatomical location, the liver is exposed to a multitude of toxins and xenobiotics, including medications and alcohol, as well as to infection by hepatotropic viruses, and therefore, is highly susceptible to tissue injury. Cell death in the liver occurs mainly by apoptosis or necrosis, with apoptosis also being the physiologic route to eliminate damaged or infected cells and to maintain tissue homeostasis. Liver cells, especially hepatocytes and cholangiocytes, are particularly susceptible to death receptor-mediated apoptosis, given the ubiquitous expression of the death receptors in the organ. In a quite unique way, death receptor-induced apoptosis in these cells is mediated by both mitochondrial and lysosomal permeabilization. Signaling between the endoplasmic reticulum and the mitochondria promotes hepatocyte apoptosis in response to excessive free fatty acid generation during the metabolic syndrome. These cell death pathways are partially regulated by microRNAs. Necrosis in the liver is generally associated with acute injury (i.e., ischemia/reperfusion injury) and has been long considered an unregulated process. Recently, a new form of “programmed” necrosis (named necroptosis) has been described: the role of necroptosis in the liver has yet to be explored. However, the minimal expression of a key player in this process in the liver suggests this form of cell death may be uncommon in liver diseases. Because apoptosis is a key feature of so many diseases of the liver, therapeutic modulation of liver cell death holds promise. An updated overview of these concepts is given in this article. PMID:23720337

  4. Estradiol inhibits osteoblast apoptosis via promotion of autophagy through the ER-ERK-mTOR pathway.

    Science.gov (United States)

    Yang, Yue-Hua; Chen, Ke; Li, Bo; Chen, Jiang-Wei; Zheng, Xin-Feng; Wang, Yu-Ren; Jiang, Sheng-Dan; Jiang, Lei-Sheng

    2013-11-01

    activation of Caspase-3 and induced autophagy through inhibition of phospho-mammalian target of rapamycin (p-mTOR). Both 3-methyladenine (3MA) and U0126 led to increase of apoptosis in osteoblasts with serum deprivation. Estradiol failed to over-ride the inhibitory effect of 3MA on phosphorylation of AKT but directly led to dephosphorylation of mTOR and upregulation of LC3 protein expression. However, the estradiol-enhanced LC3 protein expression was significantly suppressed by U0126 through inhibition of phosphorylation of extracellular signal-regulated kinase (ERK). Estradiol rescued osteoblast apoptosis via promotion of autophagy through the ER-ERK-mTOR pathway.

  5. Sindbis viral vector induced apoptosis requires translational inhibition and signaling through Mcl-1 and Bak

    Directory of Open Access Journals (Sweden)

    Meruelo Daniel

    2010-02-01

    translation is required for inhibition of apoptosis. With this information vectors can be designed, which express or repress proteins implicated in this study, to enhance their therapeutic potential.

  6. Sirtuin 6 Modulates Hypoxia-induced Apoptosis in Osteoblasts via Inhibition of Glycolysis: Implication for Pathogenesis of Periapical Lesions.

    Science.gov (United States)

    Kok, Sang-Heng; Hou, Kuo-Liang; Hong, Chi-Yuan; Chao, Ling-Hsiu; Hsiang-Hua Lai, Eddie; Wang, Han-Wei; Yang, Hsiang; Shun, Chia-Tung; Wang, Juo-Song; Lin, Sze-Kwan

    2015-10-01

    Osteoblast apoptosis is important in the regulation of inflammatory bone resorption. Hypoxia resulting from inflammation enhances glycolysis and apoptosis. Sirtuin 6 (SIRT6) is a modulator of glucose metabolism and apoptosis. In the study we assessed the role of SIRT6 in hypoxia-induced glycolysis and apoptosis in osteoblasts, with special attention on the significance of these cellular processes in periapical lesions. Human bone marrow-derived osteoblasts were cultured under hypoxia. Expression of lactate dehydrogenase A was examined by Western blot, and production of lactate was measured by colorimetric assay. Cleavage of poly (adenosine diphosphate ribose) polymerase was used as an apoptosis marker and assessed by Western blot. SIRT6 was overexpressed in osteoblasts by lentiviral gene transduction, and then glycolytic and apoptotic responses were studied. In a rat model of bacteria-induced periapical lesions, expressions of SIRT6 and markers of glycolysis and apoptosis in osteoblasts were examined. Hypoxia enhanced lactate dehydrogenase A expression and lactate production in osteoblasts. Poly (adenosine diphosphate ribose) polymerase cleavage was induced by hypoxia or lactate treatment. SIRT6 suppressed hypoxia-augmented glycolysis and inhibited apoptosis induced by hypoxia or lactate treatment. Expression of SIRT6 in osteoblasts was downregulated by hypoxia and inflammatory mediators. Development of periapical lesions in rats was associated with decreased expression of SIRT6 and increased glycolysis and apoptosis in osteoblasts. Our study suggested that hypoxia-induced apoptosis of osteoblasts is dependent on glycolytic activity. SIRT6 is a negative regulator of inflammation and may alleviate periapical lesions by suppressing osteoblastic glycolysis and apoptosis. Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  7. Autophagy regulates chlorpyrifos-induced apoptosis in SH-SY5Y cells

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jae Hyeon [Department of Pharmacology, College of Medicine, Hanyang University (Korea, Republic of); Hanyang Biomedical Research Institute, Seoul (Korea, Republic of); Graduate School of Biomedical Science and Engineering, Hanyang University, Seoul (Korea, Republic of); Lee, Jeong Eun [Department of Pharmacology, College of Medicine, Hanyang University (Korea, Republic of); Hanyang Biomedical Research Institute, Seoul (Korea, Republic of); Shin, In Chul [Department of Pharmacology, College of Medicine, Hanyang University (Korea, Republic of); Koh, Hyun Chul, E-mail: hckoh@hanyang.ac.kr [Department of Pharmacology, College of Medicine, Hanyang University (Korea, Republic of); Hanyang Biomedical Research Institute, Seoul (Korea, Republic of); Graduate School of Biomedical Science and Engineering, Hanyang University, Seoul (Korea, Republic of)

    2013-04-01

    Recent studies have shown that up-regulation of autophagy may be a tractable therapeutic intervention for clearing disease-causing proteins, including α-synuclein, ubiquitin, and other misfolded or aggregated proteins in pesticide-induced neurodegeneration. In a previous study, we reported that chlorpyrifos (CPF)-induced mitochondria-dependent apoptosis is mediated through reactive oxygen species in SH-SY5Y cells. In this study, we explored a novel pharmacotherapeutic approach to prevent CPF neurotoxicity involving the regulation of autophagy. We investigated the modulation of CPF-induced apoptosis according to autophagy regulation. We found that CPF induced apoptosis in SH-SY5Y cells, as demonstrated by the activation of caspase-3 and nuclear condensation. In addition, we observed that cells treated with CPF underwent autophagic cell death by monitoring the expression of LC3-II and p62. Pretreatment with the autophagy inducer rapamycin significantly enhanced the cell viability of CPF-exposed cells, and the enhancement of cell viability was partially due to alleviation of CPF-induced apoptosis via a decrease in levels of cleaved caspase-3. Specifically, rapamycin pretreatment decreased Bax and increased Bcl-2 expression in mitochondria. In addition, rapamycin significantly decreased cytochrome c release in from mitochondria into the cytosol. However, pretreatment of cells with the autophagy inhibitor, 3-methyladenine (3MA), remarkably increased CPF toxicity in these cells; this with correlated with increased expression of Bax and decreased expression of Bcl-2 in mitochondria. Our results suggest that CPF-induced cytotoxicity is modified by autophagy regulation and that rapamycin protects against CPF-induced apoptosis by enhancing autophagy. Pharmacologic induction of autophagy by rapamycin may be a useful treatment strategy in neurodegenerative disorders. - Highlights: ► Chlorpyrifos (CPF) is cytotoxic to SH-SY5Y cells ► CPF-induced cytotoxicity is mediated by

  8. Epithelial apoptosis: cause or consequence of ulcerative colitis?

    DEFF Research Database (Denmark)

    Seidelin, Jakob Benedict; Nielsen, Ole Haagen

    2009-01-01

    OBJECTIVE: Epithelial apoptosis rates are increased in ulcerative colitis (UC). The increased apoptosis rate could expose mucosal cells to luminal pathogens and thereby be regarded as a primary pathogenic factor in UC. On the other hand, the local inflammatory reaction could cause epithelial...... apoptosis secondary to the release of cytotoxic mediators. If apoptosis is a primary defect, apoptosis rates could influence the degree of spreading of inflammation and the clinical course of UC. If apoptosis is a side effect of local inflammation, apoptosis rates would be expected only to correlate...... with the degree of local inflammation. The aim of the study was to investigate the relationship between epithelial apoptosis and clinical characteristics of UC. MATERIAL AND METHODS: Twenty patients with UC (12 with active disease) and 20 control subjects were included. Freshly isolated colonic epithelial cells...

  9. Mitochondrial pathway of apoptosis and related proteins in placenta ...

    African Journals Online (AJOL)

    eclampsia (PE).This study aimed at evaluating the mitochondrial pathway of apoptosis in placenta of pregnant women with pre-eclampsia and correlate it with severity and pregnancy outcome . Apoptosis was assessed by measuring DNA ...

  10. Curcumin significantly enhances dual PI3K/Akt and mTOR inhibitor NVP-BEZ235-induced apoptosis in human renal carcinoma Caki cells through down-regulation of p53-dependent Bcl-2 expression and inhibition of Mcl-1 protein stability.

    Directory of Open Access Journals (Sweden)

    Bo Ram Seo

    Full Text Available The PI3K/Akt and mTOR signaling pathways are important for cell survival and growth, and they are highly activated in cancer cells compared with normal cells. Therefore, these signaling pathways are targets for inducing cancer cell death. The dual PI3K/Akt and mTOR inhibitor NVP-BEZ235 completely inhibited both signaling pathways. However, NVP-BEZ235 had no effect on cell death in human renal carcinoma Caki cells. We tested whether combined treatment with natural compounds and NVP-BEZ235 could induce cell death. Among several chemopreventive agents, curcumin, a natural biologically active compound that is extracted from the rhizomes of Curcuma species, markedly induced apoptosis in NVP-BEZ235-treated cells. Co-treatment with curcumin and NVP-BEZ235 led to the down-regulation of Mcl-1 protein expression but not mRNA expression. Ectopic expression of Mcl-1 completely inhibited curcumin plus NVP-NEZ235-induced apoptosis. Furthermore, the down-regulation of Bcl-2 was involved in curcumin plus NVP-BEZ235-induced apoptosis. Curcumin or NVP-BEZ235 alone did not change Bcl-2 mRNA or protein expression, but co-treatment reduced Bcl-2 mRNA and protein expression. Combined treatment with NVP-BEZ235 and curcumin reduced Bcl-2 expression in wild-type p53 HCT116 human colon carcinoma cells but not p53-null HCT116 cells. Moreover, Bcl-2 expression was completely reversed by treatment with pifithrin-α, a p53-specific inhibitor. Ectopic expression of Bcl-2 also inhibited apoptosis in NVP-BE235 plus curcumin-treated cells. In contrast, NVP-BEZ235 combined with curcumin did not have a synergistic effect on normal human skin fibroblasts and normal human mesangial cells. Taken together, combined treatment with NVP-BEZ235 and curcumin induces apoptosis through p53-dependent Bcl-2 mRNA down-regulation at the transcriptional level and Mcl-1 protein down-regulation at the post-transcriptional level.

  11. Regional differences in viral growth and central nervous system injury correlate with apoptosis.

    Science.gov (United States)

    Richardson-Burns, Sarah M; Tyler, Kenneth L

    2004-05-01

    Infection of neonatal mice with reovirus T3 Dearing (T3D), the prototypic neurotropic reovirus, causes fatal encephalitis associated with neuronal injury and virus-induced apoptosis throughout the brain. T3D variant K (VarK) is an antigenic variant that has a nearly 1 million-fold reduction in neurovirulence following intracerebral (i.c.) inoculation compared to T3D and a restricted pattern of central nervous system injury with damage limited to the hippocampus, sparing other brain regions. We wished to determine whether the restricted pattern of VarK-induced injury was due to a reduced capacity to replicate in or injure cortical, as opposed to hippocampal, tissue. We found that following i.c. inoculation, VarK grew to similar titers as T3D in the hippocampus but had significantly lower titers in the cortex. Both viruses grew to identical titers and infected the same percentage of cells in mouse primary hippocampal cultures (MHC). In mouse primary cortical cultures (MCC) both the number of infected cells and the viral yield per infected cell were significantly lower for VarK than T3D. VarK-induced apoptosis was limited to the hippocampus in vivo, and in vitro both viruses induced apoptosis equally in MHC but VarK induced significantly less apoptosis than T3D in MCC. Growth of T3D in MCC was reduced to levels comparable to those of VarK following treatment of MCC with caspase inhibitors. Conversely, induction of apoptosis in VarK-infected MCC with fatty acid synthase-activating antibody significantly enhanced viral yield. These results suggest that the decreased neurovirulence of VarK may be due to its failure to efficiently induce apoptosis in cortical neurons.

  12. Promotion of mitochondrial energy metabolism during hepatocyte apoptosis in a rat model of acute liver failure.

    Science.gov (United States)

    Chen, Li-Yan; Yang, Baoshan; Zhou, Li; Ren, Feng; Duan, Zhong-Ping; Ma, Ying-Ji

    2015-10-01

    Hepatocyte apoptosis and energy metabolism in mitochondria have an important role in the mechanism of acute liver failure (ALF). However, data on the association between apoptosis and the energy metabolism of hepatocytes are lacking. The current study assessed the activity of several key enzymes in mitochondria during ALF, including citrate synthase (CS), carnitine palmitoyltransferase‑1 (CPT‑1) and cytochrome c oxidase (COX), which are involved in hepatocyte energy metabolism. A total of 40 male Sprague‑Dawley rats were divided into five groups and administered D‑galactosamine and lipopolysaccharide to induce ALF. Hepatic pathology and terminal deoxynucleotidyl transferase‑mediated dUTP nick end labeling examinations indicated that hepatocyte apoptosis was observed at 4 h and increased 8 h after ALF. Hepatocyte necrosis appeared at 12 h and was significantly higher at 24 h with inflammatory cell invasion. The results measured by electron microscopy indicated that ultrastructural changes in mitochondria began at 4 h and the mitochondrial outer membrane was completely disrupted at 24 h resulting in mitochondrial collapse. The expression of CS, CPT‑1 and COX was measured and analyzed using assay kits. The activity and protein expression of CS, CPT‑1 and COX began to increase at 4 h, reached a peak at 8 h and decreased at 12 h during ALF. The activities of CS, CPT‑1 and COX were enhanced during hepatocyte apoptosis suggesting that these enzymes are involved in the initiation and development of ALF. Therefore, these results demonstrated that energy metabolism is important in hepatocyte apoptosis during ALF and hepatocyte apoptosis is an active and energy‑consuming procedure. The current study on how hepatocyte energy metabolism affects the transmission of death signals may provide a basis for the early diagnosis and development of an improved therapeutic strategy for ALF.

  13. Antiaging Gene Klotho Attenuates Pancreatic β-Cell Apoptosis in Type 1 Diabetes.

    Science.gov (United States)

    Lin, Yi; Sun, Zhongjie

    2015-12-01

    Apoptosis is the major cause of death of insulin-producing β-cells in type 1 diabetes mellitus (T1DM). Klotho is a recently discovered antiaging gene. We found that the Klotho gene is expressed in pancreatic β-cells. Interestingly, halplodeficiency of Klotho (KL(+/-)) exacerbated streptozotocin (STZ)-induced diabetes (a model of T1DM), including hyperglycemia, glucose intolerance, diminished islet insulin storage, and increased apoptotic β-cells. Conversely, in vivo β-cell-specific expression of mouse Klotho gene (mKL) attenuated β-cell apoptosis and prevented STZ-induced diabetes. mKL promoted cell adhesion to collagen IV, increased FAK and Akt phosphorylation, and inhibited caspase 3 cleavage in cultured MIN6 β-cells. mKL abolished STZ- and TNFα-induced inhibition of FAK and Akt phosphorylation, caspase 3 cleavage, and β-cell apoptosis. These promoting effects of Klotho can be abolished by blocking integrin β1. Therefore, these cell-based studies indicated that Klotho protected β-cells by inhibiting β-cell apoptosis through activation of the integrin β1-FAK/Akt pathway, leading to inhibition of caspase 3 cleavage. In an autoimmune T1DM model (NOD), we showed that in vivo β-cell-specific expression of mKL improved glucose tolerance, attenuated β-cell apoptosis, enhanced insulin storage in β-cells, and increased plasma insulin levels. The beneficial effect of Klotho gene delivery is likely due to attenuation of T-cell infiltration in pancreatic islets in NOD mice. Overall, our results demonstrate for the first time that Klotho protected β-cells in T1DM via attenuating apoptosis. © 2015 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.

  14. miR-326 targets antiapoptotic Bcl-xL and mediates apoptosis in human platelets.

    Directory of Open Access Journals (Sweden)

    Shifang Yu

    Full Text Available Platelets play crucial roles in hemostasis, thrombosis, wound healing, inflammation, angiogenesis, and tumor metastases. Because they are anucleated blood cells, platelets lack nuclear DNA, but they do contain mitochondrial DNA, which plays a key role in regulating apoptosis. Recent evidence has suggested that miRNAs are also involved in regulating gene expression and apoptosis in platelets. Our previous study showed that the expression of miR-326 increased visibly when apheresis platelets were stored in vitro. The antiapoptotic Bcl-2 family regulator Bcl-xL has been identified as a putative target of miR-326. In the present study, dual reporter luciferase assays were used to characterize the function of miR-326 in the regulation of the apoptosis of platelet cells. These assays demonstrated that miR-326 bound to the 3'-translated region of Bcl-xL. To directly assess the functional effects of miR-326 expression, levels of Bcl-xL and the apoptotic status of stored apheresis platelets were measured after transfection of miR-326 mimic or inhibitor. Results indicated that miR-326 inhibited Bcl-xL expression and induced apoptosis in stored platelets. Additionally, miR-326 inhibited Bcl-2 protein expression and enhanced Bak expression, possibly through an indirect mechanism, though there was no effect on the expression of Bax. The effect of miR-326 appeared to be limited to apoptosis, with no significant effect on platelet activation. These results provide new insight into the molecular mechanisms affecting differential platelet gene regulation, which may increase understanding of the role of platelet apoptosis in multiple diseases.

  15. Acetylbritannilactone induces G1 arrest and apoptosis in vascular smooth muscle cells.

    Science.gov (United States)

    Liu, Bin; Han, Mei; Sun, Rong-Hua; Wang, Jun-Jie; Liu, Yue-Ping; Wen, Jin-Kun

    2011-05-19

    The present study was designed to determine the effects of Acetylbritannilactone (ABL), a naturally occurring Inula britannica L., on vascular smooth muscle cell (VSMC) proliferation and apoptosis. In vitro experiments were performed to evaluate the effects of ABL on the VSMC cycle and apoptosis stimulated by chemoattractant. In addition, to examine the effects of ABL in vivo, balloon injury to rat carotid arteries was performed. ABL treatment inhibited platelet-derived growth factor (PDGF) induced DNA synthesis and proliferation in cultured VSMC. Such growth-inhibitory effects of ABL were associated with G1 phase arrest, which were correlated with reduction of cyclins D1, A, and E expression and cyclin-dependent kinase (CDK) 2, CDK4, and CDK6 proteins, increased the CDK inhibitory protein p21cip1 expression, and enhanced the binding of p21cip1 to CDKs. In addition, ABL also induced apoptosis in proliferative VSMCs, as evidenced by the induction of a higher ratio of Bax/Bcl-2, activation of caspase-9, caspase-3, and the cleavage of endogenous substrate Poly (ADP-ribose) polymerase. However, pretreatment with pan-caspases inhibitor (z-VAD-fmk) only partially reversed ABL-induced apoptosis, suggesting the involvement of both caspase-dependent and caspase-independent pathways in these processes. Furthermore, the effects of ABL on VSMCs were associated with the downregulation of extracellular signal-regulated kinase (ERK) 1/2 signaling pathways. In vivo, ABL (26 mg/kg/day) significantly suppressed injury-induced ERK1/2 phosphorylation, and increased VSMC apoptosis 14 days after balloon injury. Our findings demonstrated that ABL was capable of suppressing the abnormal VSMC proliferation, accompanied by the induction of apoptosis in vivo and in vitro. It suggested that ABL could be considered a pharmacological candidate for the prevention of restenosis after balloon angioplasty. Copyright © 2009 Elsevier Ireland Ltd. All rights reserved.

  16. Monitoring of Apoptosis in 3D Cell Cultures by FRET and Light Sheet Fluorescence Microscopy

    Directory of Open Access Journals (Sweden)

    Petra Weber

    2015-03-01

    Full Text Available Non-radiative cell membrane associated Förster Resonance Energy Transfer (FRET from an enhanced cyan fluorescent protein (ECFP to an enhanced yellow fluorescent protein (EYFP is used for detection of apoptosis in 3-dimensional cell cultures. FRET is visualized in multi-cellular tumor spheroids by light sheet based fluorescence microscopy in combination with microspectral analysis and fluorescence lifetime imaging (FLIM. Upon application of staurosporine and to some extent after treatment with phorbol-12-myristate-13-acetate (PMA, a specific activator of protein kinase c, the caspase-3 sensitive peptide linker DEVD is cleaved. This results in a reduction of acceptor (EYFP fluorescence as well as a prolongation of the fluorescence lifetime of the donor (ECFP. Fluorescence spectra and lifetimes may, therefore, be used for monitoring of apoptosis in a realistic 3-dimensional system, while light sheet based microscopy appears appropriate for 3D imaging at low light exposure.

  17. Signaling Pathways in Cardiac Myocyte Apoptosis

    Science.gov (United States)

    Xia, Peng; Liu, Yuening

    2016-01-01

    Cardiovascular diseases, the number 1 cause of death worldwide, are frequently associated with apoptotic death of cardiac myocytes. Since cardiomyocyte apoptosis is a highly regulated process, pharmacological intervention of apoptosis pathways may represent a promising therapeutic strategy for a number of cardiovascular diseases and disorders including myocardial infarction, ischemia/reperfusion injury, chemotherapy cardiotoxicity, and end-stage heart failure. Despite rapid growth of our knowledge in apoptosis signaling pathways, a clinically applicable treatment targeting this cellular process is currently unavailable. To help identify potential innovative directions for future research, it is necessary to have a full understanding of the apoptotic pathways currently known to be functional in cardiac myocytes. Here, we summarize recent progress in the regulation of cardiomyocyte apoptosis by multiple signaling molecules and pathways, with a focus on the involvement of these pathways in the pathogenesis of heart disease. In addition, we provide an update regarding bench to bedside translation of this knowledge and discuss unanswered questions that need further investigation. PMID:28101515

  18. Bacterial DNA delays human eosinophil apoptosis

    OpenAIRE

    2009-01-01

    Bacterial DNA delays human eosinophil apoptosis correspondance: Corresponding author. Tel.: +358 3 3551 6687; fax: +358 3 3551 8082. (Ilmarinen, Pinja) (Ilmarinen, Pinja) The Immunopharmacology Research Group--> , Medical School--> , University of Tampere and Research Unit--> , Tampere University Hospital--> , Tampere--> - FINLAND (Ilmarinen, Pinja) The Immunopharmacology ...

  19. Swainsonine promotes apoptosis in human oesophageal squamous ...

    Indian Academy of Sciences (India)

    Swainsonine, a natural indolizidine alkaloid, has been reported to have antitumour effects, and can induce apoptosis in human gastric and lung cancer cells. In the present study, we evaluated the antitumour effects of swainsonine on several oesophageal squamous cell carcinoma cells and investigated relative molecular ...

  20. Host-pathogen interactions during apoptosis

    Indian Academy of Sciences (India)

    Host pathogen interaction results in a variety of responses, which include phagocytosis of the pathogen, release of cytokines, secretion of toxins, as well as production of reactive oxygen species (ROS). Recent studies have shown that many pathogens exert control on the processes that regulate apoptosis in the host.

  1. THE ROLE OF APOPTOSIS IN NEUROTOXICOLOGY

    Science.gov (United States)

    Apoptosis, a form of programmed cell death, occurs in the nervous system throughout development, but with a preponderance of cell death occurring during the prenatal and perinatal periods. Aberrant periods of increased or decreased cell death, induced by toxicants in air, water,...

  2. Calpain Activator Dibucaine Induces Platelet Apoptosis

    Directory of Open Access Journals (Sweden)

    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.

  3. Epac inhibits apoptosis of human leukocytes

    NARCIS (Netherlands)

    Grandoch, M.; Bujok, V.; Fleckenstein, D.; Schmidt, M.; Fischer, J. W.; Weber, A. -A.

    2009-01-01

    cAMP is known to participate in the regulation of apoptosis in leukocytes. Depending on the cell type, pro- and antiapoptotic effects of cAMP have been described. Thus far, most of the cAMP-dependent effects have been attributed to the activation of PKA. However, Epac proteins (direct cAMP targets

  4. Beta Catenin in Prostate Cancer Apoptosis

    Science.gov (United States)

    2014-04-01

    C., Jacquin, M. A., Marchetti, S., Munoz- Pinedo, C., Auberger, P., Pende, M., and Ricci, J. E. (2010) Glycolysis inhibition sensitizes tumor cells...for TRAIL-TZD-induced apoptosis in prostate cancer cells. AMPK is a family of serine/threonine protein kinase and is highly conserved from yeast to

  5. HIV-1 protease-induced apoptosis

    Czech Academy of Sciences Publication Activity Database

    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

  6. Host-pathogen interactions during apoptosis

    Indian Academy of Sciences (India)

    Unknown

    The adenovirus E3-14⋅7 K protein, expressed early in the life cycle of human adenoviruses to protect the virus from the antiviral response of host cells, inhibits cell death mediated by TNF-α and FasL receptors. Specific induction of apoptosis in immune cells is seen in HIV infections (Pantaleo and Fauci 1995). HIV kills ...

  7. Flow Cytometric Evaluation of Human Neutrophil Apoptosis During Nitric Oxide Generation In Vitro: The Role of Exogenous Antioxidants

    Directory of Open Access Journals (Sweden)

    Zofia Sulowska

    2005-01-01

    in vitro. The effect of exogenous supply of NO donors such as SNP, SIN-1, and GEA-3162 on the course of human neutrophil apoptosis and the role of extracellular antioxidants in this process was investigated. Isolated from peripheral blood, neutrophils were cultured in the presence or absence of NO donor compounds and antioxidants for 8, 12, and 20 hours. Apoptosis of neutrophils was determined in vitro by flow cytometric analysis of cellular DNA content and Annexin V protein binding to the cell surface. Exposure of human neutrophils to GEA-3162 and SIN-1 significantly accelerates and enhances their apoptosis in vitro in a time-dependent fashion. In the presence of SNP, intensification of apoptosis has not been revealed until 12 hours after the culture. The inhibition of GEA-3162- and SIN-1-mediated neutrophil apoptosis by superoxide dismutase (SOD but not by catalase (CAT was observed. Our results show that SOD and CAT can protect neutrophils against NO-donors-induced apoptosis and suggest that the interaction of NO and oxygen metabolites signals may determine the destructive or protective role of NO donor compounds during apoptotic neutrophil death.

  8. M-ds-P21 induces cell apoptosis in bladder cancer T24 cells through P53 independent pathway.

    Science.gov (United States)

    Wang, Haifeng; Liu, Wujiang; Jin, Jie; Zhou, Liqun; Liang, Lili; Guo, Yinglu

    2013-01-01

    To investigate the effect of M-ds-P21 on the apoptosis of bladder cancer T24 cells and its potential mechanism. Effect of M-ds-P21 on T24 cells were assessed by cell morphology and Western blot. Apoptosis was quantified by Annexin-V flow-cytometry analysis. To uncover the role of P53 in M-ds-P21-mediated apoptosis of T24 cells, we knocked down P53 before treating cells with M-ds-P21, and then assayed P21 and apoptosis-related protein by Western blot. To uncover the mechanism by which M-ds-P21 played stronger effect than ds-P21, we performed confocal microscope analyses. Both M-ds-P21 and ds-P21 treatment changed the cell morphology, leading to cell apoptosis after 3 days. Apoptosis induced by M-ds-P21 and ds-P21 treatment is not P53-dependent but caspase-dependent. Compared with ds-P21, M-ds-P21 significantly increased the bioavailability of ds-RNA in T24 cells. M-ds-P21 treatment induces more apoptotic population than ds-P21 does. The mechanism for stronger effect of M-ds-P21 is partly due to the enhanced bioavailability of ds-RNA in human bladder cancer T24 cells, and not P53-dependent but caspase-dependent.

  9. M-ds-P21 induces cell apoptosis in bladder cancer T24 cells through P53 independent pathway

    Directory of Open Access Journals (Sweden)

    Haifeng Wang

    2013-01-01

    Full Text Available Objectives: To investigate the effect of M-ds-P21 on the apoptosis of bladder cancer T24 cells and its potential mechanism. Materials and Methods: Effect of M-ds-P21 on T24 cells were assessed by cell morphology and Western blot. Apoptosis was quantified by Annexin-V flow-cytometry analysis. To uncover the role of P53 in M-ds-P21-mediated apoptosis of T24 cells, we knocked down P53 before treating cells with M-ds-P21, and then assayed P21 and apoptosis-related protein by Western blot. To uncover the mechanism by which M-ds-P21 played stronger effect than ds-P21, we performed confocal microscope analyses. Results: Both M-ds-P21 and ds-P21 treatment changed the cell morphology, leading to cell apoptosis after 3 days. Apoptosis induced by M-ds-P21 and ds-P21 treatment is not P53-dependent but caspase-dependent. Compared with ds-P21, M-ds-P21 significantly increased the bioavailability of ds-RNA in T24 cells. Conclusions: M-ds-P21 treatment induces more apoptotic population than ds-P21 does. The mechanism for stronger effect of M-ds-P21 is partly due to the enhanced bioavailability of ds-RNA in human bladder cancer T24 cells, and not P53-dependent but caspase-dependent.

  10. Apoptosis-Dependent and Apoptosis-Independent Functions of Bim in Prostate Cancer Cells

    National Research Council Canada - National Science Library

    Tang, Dean; Liu, Junwei

    2005-01-01

    ... (death, survival, proliferation/division, etc.). Our hypothesis is that, under normal, unstimulated conditions, with its apoptotic function blocked, the upregulated Bim in PCa cells plays an apoptosis-independent function...

  11. Apoptosis-Dependent and Apoptosis-Independent Functions Bim in Prostate Cancer Cells

    National Research Council Canada - National Science Library

    Liu, Junwei

    2004-01-01

    ... (death, survival, proliferation/division, etc). Our hypothesis is that, under normal, unstimulated conditions, with its apoptotic function blocked, the upregulated Bim in PCa cells play an apoptosis-independent function...

  12. Spironolactone induces apoptosis in human mononuclear cells. Association between apoptosis and cytokine suppression

    DEFF Research Database (Denmark)

    Mikkelsen, Martin; Sønder, S U; Nersting, J

    2006-01-01

    Spironolactone (SPIR) has been described to suppress accumulation of pro-inflammatory cytokines. Here, the suppression of TNF-alpha in lipopolysaccharide (LPS)-stimulated mononuclear cell cultures was confirmed. However, SPIR was also found to induce apoptosis, prompting the investigations...... of a possible association between the two effects: The apoptosis-inducing and the cytokine-suppressive effects of SPIR correlated with regard to the effective concentration range. Also, pre-incubation experiments demonstrated a temporal separation of the two effects of .... In conclusion, suppression of cytokine production by SPIR may be associated with its apoptotic potential, either directly (apoptosis is a consequence of suppressed cytokine production, or vice-versa) or indirectly (suppressed cytokine production and apoptosis are parallel but otherwise unrelated phenomena)....

  13. Induction of apoptosis in response to improved gedunin by ...

    African Journals Online (AJOL)

    Apoptosis detection assays and gene expression analysis revealed the transcriptional modulation of the apoptosis-related genes (p53, survivin and Bax), increased activity of caspase 3/7 and the condensation of nuclear chromatin, implying the induction of apoptosis by the nano-formulation in NCI-H292 cells. Conclusion: ...

  14. [Mechanism of eosinophil apoptosis and its regulation in allergic reaction].

    Science.gov (United States)

    Zhang, Hao; Liu, Yuehui; Zhu, Xinhua

    2014-04-01

    In allergic reaction activated eosinophils have been known to accumulate at the site of inflamma tion. Apoptosis of eosinophils may be involved in the inflammation resolution. In this review, we state that the apoptosis of eosinophils play a direct role in allergic reaction. Regulating the apoptosis of eosinophils can effectively alter the development of allergic inflammatory reaction.

  15. Relevancia de la apoptosis en la reproduccion femenina

    National Research Council Canada - National Science Library

    Meresman, Gabriela

    2011-01-01

    ... y al mantenimiento de los tejidos. A lo largo de la vida de un organismo, la apoptosis participa desde el desarrollo hasta la senescencia. El delicado equilibrio entre proliferacion celular y apoptosis asegura un correcto control sobre la homeostasis de los tejidos. Sin embargo una falla en ese balance dada tanto por niveles de apoptosis aumentados como...

  16. Sepia ink oligopeptide induces apoptosis and growth inhibition in human lung cancer cells

    OpenAIRE

    Zhang, Zhi; Sun, Lei; Zhou, Guoren; Xie, Peng; Ye, Jinjun

    2017-01-01

    Sepia ink oligopeptide (SIO), as a tripeptide extracted from Sepia ink, could be used as an inducer of apoptosis in human prostate cancer cells. We designed a cyclo-mimetic peptide of SIO by introducing a disulfide bond to stabilize the native peptide into beta turn structure, and produced a peptide with higher cell permeability and stability. Through labeling an FITC to the N-terminus of the peptide, the cell permeability was examined. Stabilized peptide showed enhanced cellular uptake than ...

  17. Assessment of radiation induced apoptosis in lymphocyte subpopulations; Evaluacion de la apoptosis radioinducidas en subpoblaciones linfocitarias

    Energy Technology Data Exchange (ETDEWEB)

    Perez, M. del R.; Dubner, Diana L.; Michelin, Severino; Gisone, Pablo A. [Autoridad Regulatoria Nuclear, Buenos Aires (Argentina). Gerencia de Apoyo Cientifico. Lab. de Radiopatologia; Barboza, Marcos [Hospital de Clinicas Jose San Martin, Buenos AIres (Argentina). Servicio de Imunogenetica. Citometria de Flujo

    2001-07-01

    Apoptosis is the main form of radioinduced cell death. The lymphocytes, highly radiosensitive cells, dead in interphase by apoptosis even after very low doses. It has been demonstrated that the various peripheral blood lymphocyte (PBL) types display clear differences in their radiosensitivity . The purpose of this work was the characterization of radioinduced apoptosis in total PBL and in helper and cytotoxic T-lymphocytes. Blood samples were irradiated with a gamma source with doses between 0,5 and 4 Gy, dose-rate 0,8 Gy/min. Apoptosis was evaluated at different times post irradiation (p.i.) by conventional and fluorescence microscopy. Fragmentation of DNA was determined by electrophoresis in agarose gels. Apoptosis was quantified flow cytometrically by light scatter gram and determining the percent of fixed cells stained with propidium iodide that exhibited a reduced DNA content. FITC-labelled Annexin V was used to bind cell membrane phosphatidylserine which is aberrantly exposed during apoptosis. As an additional approach for the evaluation of apoptosis we measured the mitochondrial transmembrane potential by using the cationic dye 3,3 dihexyl oxacarbocyanine iodide (DiOC{sub 6}). Chromatin condensation and apoptotic bodies were microscopically observed and internucleosomal fragmentation was revealed in electrophoresis gels. Apoptotic cell fraction displayed a dose-dependent increase with a higher radiosensitivity for CD8 T-lymphocytes. These results suggest that quantification of PBL apoptosis could be an useful biological indicator in accidental overexposures and could also provide an useful predictive test for individual radiosensitivity. The higher radiosensitivity revealed by CD8 subset could allow a better discrimination of this phenomenon. (author)

  18. Reduction of apoptosis by proanthocyanidin-induced autophagy in the human gastric cancer cell line MGC-803.

    Science.gov (United States)

    Nie, Chao; Zhou, Jie; Qin, Xiaokang; Shi, Xianming; Zeng, Qingqi; Liu, Jia; Yan, Shihai; Zhang, Lei

    2016-02-01

    Proanthocyanidins are flavonoids that are widely present in the skin and seeds of various plants, with the highest content in grape seeds. Many experiments have shown that proanthocyanidins have antitumor activity both in vivo and in vitro. Autophagy and apoptosis of tumor cells induced by drugs are two of the major causes of tumor cell death. However, reports on the effect of autophagy induced by drugs in tumor cells are not consistent and suggest that autophagy can have synergistic or antagonistic effects with apoptosis. This research was aimed at investigating whether proanthocyanidins induced autophagy and apoptosis in human gastric cancer cell line MGC-803 cells and to identify the mechanism of proanthocyanidins action to further determine the effect of proanthocyanidins-induced autophagy on apoptosis. MTT assay was used to examine the proanthocyanidin cytotoxicity against human gastric cancer cell line MGC-803. Transmission electron microscopy and monodansylcadaverine (MDC) staining were used to detect autophagy. Annexin V APC/7-AAD double staining and Hoechst 33342/propidium iodide (PI) double staining were used to explore apoptosis. Western blotting was used to determine expression of proteins related to autophagy and apoptosis. Real-time quantitative PCR technology was used to determine the mRNA level of Beclin1 and BCL-2. The results showed that proanthocyanidins exhibit a significant inhibitory effect on the human gastric cancer cell line MGC-803 proliferation in vitro and simultaneously activate autophagy and apoptosis to promote cell death. Furthermore, when proanthocyanidin-induced autophagy is inhibited, apoptosis increases significantly, proanthocyanidins can be used together with autophagy inhibitors to enhance cytotoxicity.

  19. Spermine inhibits Endoplasmic Reticulum Stress - induced Apoptosis: a New Strategy to Prevent Cardiomyocyte Apoptosis

    Directory of Open Access Journals (Sweden)

    Can Wei

    2016-02-01

    Full Text Available Background/Aims: Endoplasmic reticulum stress (ERS plays an important role in the progression of acute myocardial infarction (AMI, in part by mediating apoptosis. Polyamines, including putrescine, spermidine, and spermine, are polycations with anti-oxidative, anti-aging, and cell growth-promoting activities. This study aimed to determine the mechanisms by which spermine protects against ERS-induced apoptosis in rats following AMI. Methods and Results: AMI was established by ligation of the left anterior descending coronary artery (LAD in rats, and exogenous spermine was administered by intraperitoneal injection (2.5 mg/ml daily for 7 days pre-AMI. Spermine treatment limited infarct size, attenuated cardiac troponin I and creatinine kinase-MB release, improved cardiac function, and decreased ERS and apoptosis related protein expression. Isolated cardiomyocytes subjected to hypoxia showed significant increase in reactive oxygen species (ROS and the expression of apoptosis and ERS related proteins; these effects occurred through PERK and eIF2α phosphorylation. The addition of spermine attenuated cardiomyocyte apoptosis, suppressed the production of ROS, and inhibited ERS related pathways. Conclusions: Spermine was an effective pre-treatment strategy to attenuate cardiac ERS injury in rats, and the cardioprotective mechanism occurring through inhibition of ROS production and down regulation of the PERK-eIF2α pathway. These findings provide a novel target for the prevention of apoptosis in the setting of AMI.

  20. Integrative analysis of kinase networks in TRAIL-induced apoptosis provides a source of potential targets for combination therapy

    DEFF Research Database (Denmark)

    So, Jonathan; Pasculescu, Adrian; Dai, Anna Y.

    2015-01-01

    /threonine kinase (PXK) and AP2-associated kinase 1 (AAK1), which promote receptor endocytosis and may enable cells to resist TRAIL-induced apoptosis by enhancing endocytosis of the TRAIL receptors. We assembled protein interaction maps using mass spectrometry-based protein interaction analysis and quantitative...... combination therapies to selectively kill cancer cells....

  1. SIRT1 sensitizes hepatocellular carcinoma cells expressing hepatitis B virus X protein to oxidative stress-induced apoptosis

    Energy Technology Data Exchange (ETDEWEB)

    Srisuttee, Ratakorn [WCU, Department of Cogno-Mechatronics Engineering, Pusan National University, Busan 609-735 (Korea, Republic of); Koh, Sang Seok [Immunotherapy Research Center, Korea Research Institute of Bioscience and Biotechnology, University of Science and Technology, Daejeon 305-333 (Korea, Republic of); Department of Functional Genomics, University of Science and Technology, Daejeon 305-333 (Korea, Republic of); Malilas, Waraporn; Moon, Jeong; Cho, Il-Rae [WCU, Department of Cogno-Mechatronics Engineering, Pusan National University, Busan 609-735 (Korea, Republic of); Jhun, Byung Hak [Department of Applied Nanoscience, Pusan National University, Busan 609-735 (Korea, Republic of); Horio, Yoshiyuki [Department of Pharmacology, Sapporo Medical University, Sapporo 060-8556 (Japan); Chung, Young-Hwa, E-mail: younghc@pusan.ac.kr [WCU, Department of Cogno-Mechatronics Engineering, Pusan National University, Busan 609-735 (Korea, Republic of)

    2012-12-07

    Highlights: Black-Right-Pointing-Pointer Up-regulation of SIRT1 protein and activity sensitizes Hep3B-HBX cells to oxidative stress-induced apoptosis. Black-Right-Pointing-Pointer Nuclear localization of SIRT1 is not required for oxidation-induced apoptosis. Black-Right-Pointing-Pointer Ectopic expression and enhanced activity of SIRT1 attenuate JNK phosphorylation. Black-Right-Pointing-Pointer Inhibition of SIRT1 activity restores resistance to oxidation-induced apoptosis through JNK activation. -- Abstract: We previously showed that SIRT1 deacetylase inhibits proliferation of hepatocellular carcinoma cells expressing hepatitis B virus (HBV) X protein (HBX), by destabilization of {beta}-catenin. Here, we report another role for SIRT1 in HBX-mediated resistance to oxidative stress. Ectopic expression and enhanced activity of SIRT1 sensitize Hep3B cells stably expressing HBX to oxidative stress-induced apoptosis. SIRT1 mutant analysis showed that nuclear localization of SIRT1 is not required for sensitization of oxidation-mediated apoptosis. Furthermore, ectopic expression of SIRT1 and treatment with resveratrol (a SIRT1 activator) attenuated JNK phosphorylation, which is a prerequisite for resistance to oxidative stress-induced apoptosis. Conversely, suppression of SIRT1 activity with nicotinamide inhibited the effect of resveratrol on JNK phosphorylation, leading to restoration of resistance to oxidation-induced apoptosis. Taken together, these results suggest that up-regulation of SIRT1 under oxidative stress may be a therapeutic strategy for treatment of hepatocellular carcinoma cells related to HBV through inhibition of JNK activation.

  2. The tyrosine kinase inhibitor nintedanib activates SHP-1 and induces apoptosis in triple-negative breast cancer cells.

    Science.gov (United States)

    Liu, Chun-Yu; Huang, Tzu-Ting; Chu, Pei-Yi; Huang, Chun-Teng; Lee, Chia-Han; Wang, Wan-Lun; Lau, Ka-Yi; Tsai, Wen-Chun; Chao, Tzu-I; Su, Jung-Chen; Chen, Ming-Huang; Shiau, Chung-Wai; Tseng, Ling-Ming; Chen, Kuen-Feng

    2017-08-11

    Triple-negative breast cancer (TNBC) remains difficult to treat and urgently needs new therapeutic options. Nintedanib, a multikinase inhibitor, has exhibited efficacy in early clinical trials for HER2-negative breast cancer. In this study, we examined a new molecular mechanism of nintedanib in TNBC. The results demonstrated that nintedanib enhanced TNBC cell apoptosis, which was accompanied by a reduction of p-STAT3 and its downstream proteins. STAT3 overexpression suppressed nintedanib-mediated apoptosis and further increased the activity of purified SHP-1 protein. Moreover, treatment with either a specific inhibitor of SHP-1 or SHP-1-targeted siRNA reduced the apoptotic effects of nintedanib, which validates the role of SHP-1 in nintedanib-mediated apoptosis. Furthermore, nintedanib-induced apoptosis was attenuated in TNBC cells expressing SHP-1 mutants with constantly open conformations, suggesting that the autoinhibitory mechanism of SHP-1 attenuated the effects of nintedanib. Importantly, nintedanib significantly inhibited tumor growth via the SHP-1/p-STAT3 pathway. Clinically, SHP-1 levels were downregulated, whereas p-STAT3 was upregulated in tumor tissues, and SHP-1 transcripts were associated with improved disease-free survival in TNBC patients. Our findings revealed that nintedanib induces TNBC apoptosis by acting as a SHP-1 agonist, suggesting that targeting STAT3 by enhancing SHP-1 expression could be a viable therapeutic strategy against TNBC.

  3. TRAIL induces neutrophil apoptosis and dampens sepsis-induced organ injury in murine colon ascendens stent peritonitis.

    Directory of Open Access Journals (Sweden)

    Katharina Beyer

    Full Text Available TNF-related apoptosis inducing ligand (TRAIL influences several inflammatory reactions by partially still unknown mechanisms. TRAIL is produced and expressed by several cells of the immune system. Murine Colon Ascendens Stent Peritonitis (CASP represents a hyperinflammatory model of diffuse peritonitis. As we have shown previously, TRAIL strongly improves survival in murine CASP. This is accompanied by a significantly reduced infiltration of neutrophils in the associated lymphoid tissue. Additionally, it is known that TRAIL induces apoptosis in neutrophils and acceleration of neutrophil apoptosis enhances resolution of inflammatory reactions. In this study, we investigated the correlation of the protective effect of TRAIL in sepsis and its influence on neutrophils. We found that neutrophils infiltrating the lymphoid organs express the TRAIL-receptor DR5 at high density. Furthermore, we demonstrated that TRAIL-treatment enhances apoptosis of neutrophils in the spleen, lung and liver and decreases organ injury during sepsis. To further examine a role for neutrophils in TRAIL-mediated protection in CASP, we have depleted neutrophils 24 hours prior to CASP. In these depleted mice, administration of TRAIL was ineffective. We conclude that TRAIL induces apoptosis in tissue-infiltrating neutrophils thereby protecting organs from sepsis-induced injury.

  4. Hepatitis C virus core protein induces apoptosis-like caspase independent cell death

    Directory of Open Access Journals (Sweden)

    Gregor Michael

    2009-12-01

    Full Text Available Abstract Background Hepatitis C virus (HCV associated liver diseases may be related to apoptotic processes. Thus, we investigated the role of different HCV proteins in apoptosis induction as well as their potency to interact with different apoptosis inducing agents. Methods and Results The use of a tightly adjustable tetracycline (Tet-dependent HCV protein expression cell system with the founder osteosarcoma cell line U-2 OS allowed switch-off and on of the endogenous production of HCV proteins. Analyzed were cell lines expressing the HCV polyprotein, the core protein, protein complexes of the core, envelope proteins E1, E2 and p7, and non-structural proteins NS3 and NS4A, NS4B or NS5A and NS5B. Apoptosis was measured mainly by the detection of hypodiploid apoptotic nuclei in the absence or presence of mitomycin C, etoposide, TRAIL and an agonistic anti-CD95 antibody. To further characterize cell death induction, a variety of different methods like fluorescence microscopy, TUNEL (terminal deoxynucleotidyl transferase (TdT-catalyzed deoxyuridinephosphate (dUTP-nick end labeling assay, Annexin V staining, Western blot and caspase activation assays were included into our analysis. Two cell lines expressing the core protein but not the total polyprotein exerted a strong apoptotic effect, while the other cell lines did not induce any or only a slight effect by measuring the hypodiploid nuclei. Cell death induction was caspase-independent since it could not be blocked by zVAD-fmk. Moreover, caspase activity was absent in Western blot analysis and fluorometric assays while typical apoptosis-associated morphological features like the membrane blebbing and nuclei condensation and fragmentation could be clearly observed by microscopy. None of the HCV proteins influenced the apoptotic effect mediated via the mitochondrial apoptosis pathway while only the core protein enhanced death-receptor-mediated apoptosis. Conclusion Our data showed a caspase

  5. Downregulation of DcR3 sensitizes hepatocellular carcinoma cells to TRAIL-induced apoptosis

    Directory of Open Access Journals (Sweden)

    Liang CJ

    2017-01-01

    results showed that the TRAIL death receptor 5 (DR5 was upregulated and that DR5 neutralizing antibody abrogated the effect of SiDcR3. Our results demonstrated that downregulation of DcR3 could enhance TRAIL-mediated apoptosis in HCC through the death receptor pathway. In the future, this might be useful as a clinical treatment method of liver cancer. Keywords: apoptosis, DcR3, TRAIL, HCC, DR5, caspase-8

  6. 4SC-202 activates ASK1-dependent mitochondrial apoptosis pathway to inhibit hepatocellular carcinoma cells

    Energy Technology Data Exchange (ETDEWEB)

    Fu, Meili, E-mail: fumeilidrlinyi@tom.com [Department of Infectious Disease, Linyi People' s Hospital, Linyi 276000 (China); Wan, Fuqiang [Department of Head and Neck Surgery, Linyi Tumor Hospital, Linyi 276000 (China); Li, Zhengling [Department of Nursing, Tengzhou Central People' s Hospital, Tengzhou 277500 (China); Zhang, Fenghua [Department of Operating Room, Linyi People' s Hospital, Linyi 276000 (China)

    2016-03-04

    The aim of the present study is to investigate the potential anti-hepatocellular carcinoma (HCC) cell activity by 4SC-202, a novel class I HDAC inhibitor (HDACi). The associated signaling mechanisms were also analyzed. We showed that 4SC-202 treatment induced potent cytotoxic and proliferation–inhibitory activities against established HCC cell lines (HepG2, HepB3, SMMC-7721) and patient-derived primary HCC cells. Further, adding 4SC-202 in HCC cells activated mitochondrial apoptosis pathway, which was evidenced by mitochondrial permeability transition pore (mPTP) opening, cytochrome C cytosol release and caspase-3/-9 activation. Inhibition of this apoptosis pathway, by caspase-3/-9 inhibitors, mPTP blockers, or by shRNA-mediated knockdown of cyclophilin-D (Cyp-D, a key component of mPTP), significantly attenuated 4SC-202-induced HCC cell death and apoptosis. Reversely, over-expression of Cyp-D enhanced 4SC-202's sensitivity in HCC cells. Further studies showed that 4SC-202 induced apoptosis signal-regulating kinase 1 (ASK1) activation, causing it translocation to mitochondria and physical association with Cyp-D. This mitochondrial ASK1-Cyp-D complexation appeared required for mediating 4SC-202-induced apoptosis activation. ASK1 stable knockdown by targeted-shRNAs largely inhibited 4SC-202-induced mPTP opening, cytochrome C release, and following HCC cell apoptotic death. Together, we suggest that 4SC-202 activates ASK1-dependent mitochondrial apoptosis pathway to potently inhibit human HCC cells. - Highlights: • 4SC-202 exerts potent anti-proliferative and cytotoxic activity against established/primary HCC cells. • SC-202-induced anti-HCC cell activity relies on caspase-dependent apoptosis activation. • 4SC-202 activates Cyp-D-dependent mitochondrial apoptosis pathway in HCC cells. • 4SC-202 activates ASK1 in HCC cells, causing it translocation to mitochondria. • Mitochondrial ASK1-Cyp-D complexation mediates 4SC-202's activity in HCC cells.

  7. Interleukin-1 receptor antagonist reduced apoptosis and attenuated intestinal mucositis in a 5-fluorouracil chemotherapy model in mice.

    Science.gov (United States)

    Wu, Zhen-Qian; Han, Xiao-Dong; Wang, Yu; Yuan, Ke-Li; Jin, Zhi-Ming; Di, Jian-Zhong; Yan, Jun; Pan, Ye; Zhang, Pin; Huang, Xin-Yu; Wang, Zhi-Gang; Zheng, Qi

    2011-07-01

    The aim of this study was to investigate the relationship between changes in IL-1β expression and intestinal apoptosis after chemotherapy. And we further determine whether interleukin-1 receptor antagonist (IL-1Ra) reduces apoptosis in vivo after 5-fluorouracil (5-FU) chemotherapy in the small intestine. Intestinal mucositis was induced in mice by intraperitoneal injection of a single dose of 5-FU (200 mg/kg). IL-1Ra (1 mg/kg) was injected subcutaneously twice daily after 5-FU injection. 5-FU-induced intestinal apoptosis was detected by TUNEL assay. The expression of IL-1β induced by 5-FU in local intestinal tissue was examined by RT-PCR and immunohistochemistry. Assessment of 5-FU-induced mucositis (histology, diarrhea scores, bowel weight) was performed. The apoptosis-related proteins were investigated by western blotting analysis. The proliferation of intestine was examined by immunohistological staining of PCNA. Viability of IEC-6 cells was determined using the CCK-8 assay. The apoptosis of IEC-6 cells was examined by Hoechst 33342 staining. The variation of IL-1β expression induced by 5-FU was in accordance with the changes in intestinal apoptosis. Administration of IL-1Ra could block the destructive effect of IL-1β and reduce apoptosis in the small intestinal crypt after chemotherapy. The protection against apoptosis was in accordance with the reduction of the up-regulation of Bax and caspase 3 and the elimination of the down-regulation of Bcl-2 and Bcl-xL. Moreover, IL-1Ra attenuated the severity of intestinal mucositis induced by 5-FU and enhanced intestinal crypt proliferation. In vitro experiments showed that IL-1Ra suppressed apoptosis and increased cell viability in enterocyte IEC-6 cells treated with 5-FU. Additionally, IL-1Ra did not affect the chemotherapeutic effect of 5-FU in tumor CT-26 xenograft mice. Our studies elucidate that IL-1β is quite possibly involved in and mediated the course of intestinal apoptosis after 5-FU chemotherapy

  8. Blockage of glycolysis by targeting PFKFB3 alleviates sepsis-related acute lung injury via suppressing inflammation and apoptosis of alveolar epithelial cells.

    Science.gov (United States)

    Gong, Yuanqi; Lan, Haibing; Yu, Zhihong; Wang, Meng; Wang, Shu; Chen, Yu; Rao, Haiwei; Li, Jingying; Sheng, Zhiyong; Shao, Jianghua

    2017-09-16

    Sepsis-related acute lung injury (ALI) is characterized by excessive lung inflammation and apoptosis of alveolar epithelial cells resulting in acute hypoxemic respiratory failure. Recent studies indicated that anaerobic glycolysis play an important role in sepsis. However, whether inhibition of aerobic glycolysis exhibits beneficial effect on sepsis-induced ALI is not known. In vivo, a cecal ligation and puncture (CLP)-induced ALI mouse model was set up and mice treated with glycolytic inhibitor 3PO after CLP. The mice treated with the 3PO ameliorated the survival rate, histopathological changes, lung inflammation, lactate increased and lung apoptosis of mice with CLP-induced sepsis. In vitro, the exposure of human alveolar epithelial A549 cells to lipopolysaccharide (LPS) resulted in cell apoptosis, inflammatory cytokine production, enhanced glycolytic flux and reactive oxygen species (ROS) increased. While these changes were attenuated by 3PO treatment. Sequentially, treatment of A549 cells with lactate caused cell apoptosis and enhancement of ROS. Pretreatment with N-acetylcysteine (NAC) significantly lowered LPS and lactate-induced the generation of ROS and cell apoptosis in A549 cells. Therefore, these results indicate that anaerobic glycolysis may be an important contributor in cell apoptosis of sepsis-related ALI. Moreover, LPS specifically induces apoptotic insults to A549 cell through lactate-mediated enhancement of ROS. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. Apoptosis in the pathogenesis of Nosema ceranae (Microsporidia: Nosematidae) in honey bees (Apis mellifera).

    Science.gov (United States)

    Higes, Mariano; Juarranz, Ángeles; Dias-Almeida, Joyce; Lucena, Silvia; Botías, Cristina; Meana, Aránzazu; García-Palencia, Pilar; Martín-Hernández, Raquel

    2013-08-01

    Nosema ceranae is a parasite of the epithelial ventricular cells of the honey bee that belongs to the microsporidian phylum, a biological group of single-cell, spore-forming obligate intracellular parasites found in all major animal lineages. The ability of host cells to accommodate a large parasitic burden for several days suggests that these parasites subvert the normal host cells to ensure optimal environmental conditions for growth and development. Once infected, cells can counteract the invasive pathogen by initiating their own death by apoptosis as a defence strategy. To determine whether N. ceranae blocks apoptosis in infected ventricular cells, cell death was assessed in sections of the ventriculum from experimentally infected honey bees using the TUNEL assay and by immunohistochemistry for caspase-3. Ventricular epithelial cells from infected bees were larger than those in the uninfected control bees, and they contained N. ceranae at both mature and immature stages in the cytoplasm. Apoptotic nuclei were only observed in some restricted areas of the ventriculum, whereas apoptosis was typically observed throughout the epithelium in uninfected bees. Indeed, the apoptotic index was higher in uninfected versus infected ventriculi. Our results suggested that N. ceranae prevents apoptosis in epithelial cells of infected ventriculi, a mechanism possible designed to enhance parasite development. © 2013 John Wiley & Sons Ltd and Society for Applied Microbiology.

  10. Estrogen protects SGC7901 cells from endoplasmic reticulum stress-induced apoptosis by the Akt pathway

    Science.gov (United States)

    FU, ZHENGQI; ZOU, FENG; DENG, HAO; ZHOU, HONGYAN; LIU, LIJIANG

    2014-01-01

    Several previous studies have demonstrated that estrogen may protect cancer cells from endoplasmic reticulum stress-induced apoptosis. However, the molecular mechanisms involved are not fully understood. In the present study, human gastric adenocarcinoma SGC7901 cells were treated with tunicamycin (TM) to induce endoplasmic reticulum stress. This was demonstrated by increased glucose-regulated protein 78 expression and enhanced phosphorylation of protein kinase RNA-like endoplasmic reticulum kinase. Endoplasmic reticulum stress induced caspase-3-mediated apoptosis with the inhibition of Akt; the latter of which was measured by the activity-dependent phosphorylation at Ser473 of Akt. Simultaneous treatment of 10−9 M 17β-estradiol (E2) with TM may protect SGC7901 cells from endoplasmic reticulum stress-induced apoptosis by counteracting the inhibitory effect of TM on Akt, causing an increase in the phosphorylation of Ser473-Akt. It was concluded that low concentrations of E2 may counteract endoplasmic reticulum stress-induced inactivation of Akt to block caspase-3-mediated apoptosis. PMID:24396487

  11. Interaction of caveolin-1 with Ku70 inhibits Bax-mediated apoptosis.

    Directory of Open Access Journals (Sweden)

    Huafei Zou

    Full Text Available Caveolin-1, the structural protein component of caveolae, acts as a scaffolding protein that functionally regulates signaling molecules. We show that knockdown of caveolin-1 protein expression enhances chemotherapeutic drug-induced apoptosis and inhibits long-term survival of colon cancer cells. In vitro studies demonstrate that caveolin-1 is a novel Ku70-binding protein, as shown by the binding of the scaffolding domain of caveolin-1 (amino acids 82-101 to the caveolin-binding domain (CBD of Ku70 (amino acids 471-478. Cell culture data show that caveolin-1 binds Ku70 after treatment with chemotherapeutic drugs. Mechanistically, we found that binding of caveolin-1 to Ku70 inhibits the chemotherapeutic drug-induced release of Bax from Ku70, activation of Bax, translocation of Bax to mitochondria and apoptosis. Potentiation of apoptosis by knockdown of caveolin-1 protein expression is greatly reduced in the absence of Bax expression. Finally, we found that overexpression of wild type Ku70, but not a mutant form of Ku70 that cannot bind to caveolin-1 (Ku70 Φ→A, limits the chemotherapeutic drug-induced Ku70/Bax dissociation and apoptosis. Thus, caveolin-1 acts as an anti-apoptotic protein in colon cancer cells by binding to Ku70 and inhibiting Bax-dependent cell death.

  12. Carnosic acid induces apoptosis of hepatocellular carcinoma cells via ROS-mediated mitochondrial pathway.

    Science.gov (United States)

    Zhang, Xinrui; Chen, Yiling; Cai, Guangsheng; Li, Xin; Wang, Di

    2017-11-01

    Carnosic acid (CA), an important bioactive phenolic diterpene mainly found in labiate plants, exerts various biological functions, including antioxidant, anti-inflammatory, antitumor, and neuroprotective activities. In the present study, we proved the deleterious effects of CA against hepatocellular carcinoma (HCC) in both in vitro and in vivo models. In vitro, CA significantly decreased cell viability, inhibited cell proliferation and migration, enhanced apoptosis, and increased caspase-3, -8, and -9 activities in HepG2 and SMMC-7721 cells. Specifically, CA led to a decreased mitochondrial membrane potential (MMP) and increases in intracellular reactive oxygen species (ROS) levels and apoptosis-related protein expression. Pre-incubation of HCC cells with N-Acetyl-l-cysteine (NAC), a ROS inhibitor, strongly suppressed CA-induced apoptotic phenomena, including reduced cell viability, excessive ROS levels, MMP decreases, and abnormal protein expression, suggesting an association of CA-induced apoptosis with oxidative stress-mediated mitochondrial pathways. In HepG2-and SMMC-7721-xenograft tumor mouse models, treatment with CA inhibited tumor growth and modulated apoptosis-related protein expression, confirming the anti-HCC effects of this chemical. Moreover, the CA-mediated anti-HCC effects associated with oxidative stress provide experimental evidence to support the potential use of CA as a drug therapy for HCC. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Fish oil increases mitochondrial phospholipid unsaturation, upregulating reactive oxygen species and apoptosis in rat colonocytes

    Science.gov (United States)

    Hong, Mee Young; Chapkin, Robert S.; Barhoumi, Rola; Burghardt, Robert C.; Turner, Nancy D.; Henderson, Cara E.; Sanders, Lisa M.; Fan, Yang-Yi; Davidson, Laurie A.; Murphy, Mary E.; hide

    2002-01-01

    We have shown that a combination of fish oil (high in n-3 fatty acids) with the butyrate-producing fiber pectin, upregulates apoptosis in colon cells exposed to the carcinogen azoxymethane, protecting against colon tumor development. We now hypothesize that n-3 fatty acids prime the colonocytes such that butyrate can initiate apoptosis. To test this, 30 Sprague-Dawley rats were provided with diets differing in the fatty acid composition (corn oil, fish oil or a purified fatty acid ethyl ester diet). Intact colon crypts were exposed ex vivo to butyrate, and analyzed for reactive oxygen species (ROS), mitochondrial membrane potential (MMP), translocation of cytochrome C to the cytosol, and caspase-3 activity (early events in apoptosis). The fatty acid composition of the three major mitochondrial phospholipids was also determined, and an unsaturation index calculated. The unsaturation index in cardiolipin was correlated with ROS levels (R = 0.99; P = 0.02). When colon crypts from fish oil and FAEE-fed rats were exposed to butyrate, MMP decreased (P = 0.041); and translocation of cytochrome C to the cytosol (P = 0.037) and caspase-3 activation increased (P = 0.032). The data suggest that fish oil may prime the colonocytes for butyrate-induced apoptosis by enhancing the unsaturation of mitochondrial phospholipids, especially cardiolipin, resulting in an increase in ROS and initiating apoptotic cascade.

  14. ALA-PDT inhibits proliferation and promotes apoptosis of SCC cells through STAT3 signal pathway.

    Science.gov (United States)

    Qiao, Li; Mei, Zhusong; Yang, Zhiyong; Li, Xinji; Cai, Hong; Liu, Wei

    2016-06-01

    Previous studies suggest that apoptosis of carcinoma cells led by photodynamics is mainly intrinsic apoptosis, but whether the extrinsic pathway is involved in the treatment of carcinoma by photodynamic therapy is not confirmed. This research investigated the effect of ALA-PDT on the proliferation and apoptosis of SCC cell A431 and COLO-16, and discussed the role played by JAK/STAT3 signal pathway in this process. Our data showed that the expression levels STAT3 and p-STAT3 protein in the cancer tissue are higher than the corresponding adjacent tissue to carcinoma. The expression level of p-STAT3 in cancerous tissue has a correlation with the tumor size and tissue histopathological differentiation. ALA-PDT could inhibit proliferation of A431 and COLO-16 cells, STAT3 knock down could enhance ALA-PDT's inhibition of cell proliferation, and promote apoptosis induced by ALA-PDT. On the other hand, overexpression of STAT3 has the opposite effect. In addition, ALA-PDT can weaken the protein expression of STAT3 and its target gene Bcl-2 mRNA, and ALA-PDT can strengthen the protein expression of STAT3's target gene Bax mRNA. Overexpression of STAT3 can offset the effect on Bcl-2 and Bax by ALA-PDT; on the other hand, STAT3 knocking down can strengthen ALA-PDT's effect on Bcl-2 and Bax. Copyright © 2016. Published by Elsevier B.V.

  15. Biguanides sensitize leukemia cells to ABT-737-induced apoptosis by inhibiting mitochondrial electron transport

    Science.gov (United States)

    Velez, Juliana; Pan, Rongqing; Lee, Jason T.C.; Enciso, Leonardo; Suarez, Marta; Duque, Jorge Eduardo; Jaramillo, Daniel; Lopez, Catalina; Morales, Ludis; Bornmann, William; Konopleva, Marina; Krystal, Gerald; Andreeff, Michael; Samudio, Ismael

    2016-01-01

    Metformin displays antileukemic effects partly due to activation of AMPK and subsequent inhibition of mTOR signaling. Nevertheless, Metformin also inhibits mitochondrial electron transport at complex I in an AMPK-independent manner, Here we report that Metformin and rotenone inhibit mitochondrial electron transport and increase triglyceride levels in leukemia cell lines, suggesting impairment of fatty acid oxidation (FAO). We also report that, like other FAO inhibitors, both agents and the related biguanide, Phenformin, increase sensitivity to apoptosis induction by the bcl-2 inhibitor ABT-737 supporting the notion that electron transport antagonizes activation of the intrinsic apoptosis pathway in leukemia cells. Both biguanides and rotenone induce superoxide generation in leukemia cells, indicating that oxidative damage may sensitize toABT-737 induced apoptosis. In addition, we demonstrate that Metformin sensitizes leukemia cells to the oligomerization of Bak, suggesting that the observed synergy with ABT-737 is mediated, at least in part, by enhanced outer mitochondrial membrane permeabilization. Notably, Phenformin was at least 10-fold more potent than Metformin in abrogating electron transport and increasing sensitivity to ABT-737, suggesting that this agent may be better suited for targeting hematological malignancies. Taken together, our results suggest that inhibition of mitochondrial metabolism by Metformin or Phenformin is associated with increased leukemia cell susceptibility to induction of intrinsic apoptosis, and provide a rationale for clinical studies exploring the efficacy of combining biguanides with the orally bioavailable derivative of ABT-737, Venetoclax. PMID:27283492

  16. The RNA-binding protein tristetraprolin schedules apoptosis of pathogen-engaged neutrophils during bacterial infection.

    Science.gov (United States)

    Ebner, Florian; Sedlyarov, Vitaly; Tasciyan, Saren; Ivin, Masa; Kratochvill, Franz; Gratz, Nina; Kenner, Lukas; Villunger, Andreas; Sixt, Michael; Kovarik, Pavel

    2017-06-01

    Protective responses against pathogens require a rapid mobilization of resting neutrophils and the timely removal of activated ones. Neutrophils are exceptionally short-lived leukocytes, yet it remains unclear whether the lifespan of pathogen-engaged neutrophils is regulated differently from that in the circulating steady-state pool. Here, we have found that under homeostatic conditions, the mRNA-destabilizing protein tristetraprolin (TTP) regulates apoptosis and the numbers of activated infiltrating murine neutrophils but not neutrophil cellularity. Activated TTP-deficient neutrophils exhibited decreased apoptosis and enhanced accumulation at the infection site. In the context of myeloid-specific deletion of Ttp, the potentiation of neutrophil deployment protected mice against lethal soft tissue infection with Streptococcus pyogenes and prevented bacterial dissemination. Neutrophil transcriptome analysis revealed that decreased apoptosis of TTP-deficient neutrophils was specifically associated with elevated expression of myeloid cell leukemia 1 (Mcl1) but not other antiapoptotic B cell leukemia/lymphoma 2 (Bcl2) family members. Higher Mcl1 expression resulted from stabilization of Mcl1 mRNA in the absence of TTP. The low apoptosis rate of infiltrating TTP-deficient neutrophils was comparable to that of transgenic Mcl1-overexpressing neutrophils. Our study demonstrates that posttranscriptional gene regulation by TTP schedules the termination of the antimicrobial engagement of neutrophils. The balancing role of TTP comes at the cost of an increased risk of bacterial infections.

  17. Effect of Acrylamide on Oocyte Nuclear Maturation and Cumulus Cells Apoptosis in Mouse In Vitro

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    Liu, Shuzhen; Jiang, Ligang; Zhong, Tao; Kong, Shuhui; Zheng, Rongbin; Kong, Fengyun; Zhang, Cong; Zhang, Lei; An, Liguo

    2015-01-01

    Acrylamide (ACR) is a chemical compound with severe neurotoxicity, genotoxicity, carcinogenicity and reproductive toxicity. Recent studies showed that ACR impairs the function of reproductive organs, e.g., epididymis and testes. In vitro maturation of mouse oocyte is a sensitive assay to identify potential chemical hazard to female fertility. The aim of this study was to evaluate the adverse effects of ACR on the nuclear maturation and cumulus cells apoptosis of mouse oocytes in vitro. Cumulus–oocyte complexes were incubated in a maturation medium containing 0, 5, 10 and 20 μM of ACR. Chromosome alignment and spindle morphology of oocytes was determined by immunofluorescence and confocal microscopy. Our results showed that oocytes exposed to different doses of ACR in vitro were associated with a significant decrease of oocyte maturation, significant increase of chromosome misalignment rate, occurrence of abnormal spindle configurations, and the inhibition of oocyte parthenogenetic activation. Furthermore, apoptosis of cumulus cells was determined by TUNEL and CASPASE-3 assay. Results showed that apoptosis in cumulus cells was enhanced and the expression of CASPASE-3 was increased after cumulus–oocyte complexes were exposed to ACR. Therefore, ACR may affect the nuclear maturation of oocytes via the apoptosis of cumulus cells in vitro. PMID:26275143

  18. Induction of DNA synthesis and apoptosis are separable functions of E2F-1

    DEFF Research Database (Denmark)

    Phillips, A C; Bates, S; Ryan, K M

    1997-01-01

    The family of E2F transcription factors have an essential role in mediating cell cycle progression, and recently, one of the E2F protein family, E2F-1, has been shown to participate in the induction of apoptosis. Cooperation between E2F and the p53 tumor suppressor protein in this apoptotic...... response had led to the suggestion that cell cycle progression induced by E2F-1 expression provides an apoptotic signal when placed in conflict with an arrest to cell cycle progression, such as provided by p53. We show here that although apoptosis is clearly enhanced by p53, E2F-1 can induce significant...... apoptosis in the absence of p53. Furthermore, this apoptotic function of E2F-1 is separable from the ability to accelerate entry into DNA synthesis. Analysis of E2F-1 mutants indicates that although DNA-binding is required, transcriptional transactivation is not necessary for the induction of apoptosis by E...

  19. HIV-1 Tat-mediated apoptosis in human blood-retinal barrier-associated cells.

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    Xin Che

    Full Text Available HIV-1-associated ocular complications, such as microvasculopathies, can lead to the loss of vision in HIV-1-infected patients. Even in patients under highly active antiretroviral therapy, ocular lesions are unavoidable. Ocular complications have been demonstrated to be closely related to the breakdown of the blood-retinal-barrier (BRB; however, the underlying mechanism is not clear. The data from this study indicated that the HIV-1 Tat protein induced the apoptosis of human retinal microvascular endothelial cells (HRMECs and retinal pigmen epithelium (RPE cells, which compose the inner BRB and the outer BRB, respectively. In addition, this study found that the activation of N-methyl-D-aspartate receptors (NMDARs was involved in the apoptosis of RPE cells, but it caused no changes in HRMECs. Furthermore, both cell types exhibited enhanced expression of Bak, Bax and Cytochrome c. The inhibition of Tat activity protected against the apoptosis induced by NMDAR activation and prevented the dysregulation of Bak, Bax and Cytochrome c, revealing an important role for the mitochondrial pathway in HIV-1 Tat-induced apoptosis. Together, these findings suggest a possible mechanism and may identify a potential therapeutic strategy for HIV-1-associated ocular complications.

  20. A synthetic ion transporter that disrupts autophagy and induces apoptosis by perturbing cellular chloride concentrations

    Science.gov (United States)

    Busschaert, Nathalie; Park, Seong-Hyun; Baek, Kyung-Hwa; Choi, Yoon Pyo; Park, Jinhong; Howe, Ethan N. W.; Hiscock, Jennifer R.; Karagiannidis, Louise E.; Marques, Igor; Félix, Vítor; Namkung, Wan; Sessler, Jonathan L.; Gale, Philip A.; Shin, Injae

    2017-07-01

    Perturbations in cellular chloride concentrations can affect cellular pH and autophagy and lead to the onset of apoptosis. With this in mind, synthetic ion transporters have been used to disturb cellular ion homeostasis and thereby induce cell death; however, it is not clear whether synthetic ion transporters can also be used to disrupt autophagy. Here, we show that squaramide-based ion transporters enhance the transport of chloride anions in liposomal models and promote sodium chloride influx into the cytosol. Liposomal and cellular transport activity of the squaramides is shown to correlate with cell death activity, which is attributed to caspase-dependent apoptosis. One ion transporter was also shown to cause additional changes in lysosomal pH, which leads to impairment of lysosomal enzyme activity and disruption of autophagic processes. This disruption is independent of the initiation of apoptosis by the ion transporter. This study provides the first experimental evidence that synthetic ion transporters can disrupt both autophagy and induce apoptosis.

  1. Biomarkers of Chondrocyte Apoptosis and Autophagy in Osteoarthritis

    Science.gov (United States)

    Musumeci, Giuseppe; Castrogiovanni, Paola; Trovato, Francesca Maria; Weinberg, Annelie Martina; Al-Wasiyah, Mohammad K.; Alqahtani, Mohammed H.; Mobasheri, Ali

    2015-01-01

    Cell death with morphological and molecular features of apoptosis has been detected in osteoarthritic (OA) cartilage, which suggests a key role for chondrocyte death/survival in the pathogenesis of OA. Identification of biomarkers of chondrocyte apoptosis may facilitate the development of novel therapies that may eliminate the cause or, at least, slow down the degenerative processes in OA. The aim of this review was to explore the molecular markers and signals that induce chondrocyte apoptosis in OA. A literature search was conducted in PubMed, Scopus, Web of Science and Google Scholar using the keywords chondrocyte death, apoptosis, osteoarthritis, autophagy and biomarker. Several molecules considered to be markers of chondrocyte apoptosis will be discussed in this brief review. Molecular markers and signalling pathways associated with chondroycte apoptosis may turn out to be therapeutic targets in OA and approaches aimed at neutralizing apoptosis-inducing molecules may at least delay the progression of cartilage degeneration in OA. PMID:26334269

  2. Molecular mechanisms of liver injury: apoptosis or necrosis.

    Science.gov (United States)

    Wang, Kewei

    2014-10-01

    Hepatic apoptosis is thought of as a prevalent mechanism in most forms of liver injury. However, the role of hepatic apoptosis is often intermixed with the cellular necrosis. It remains unknown how apoptosis is relevant to the progression of the liver injury. This review summarizes the characteristics of both hepatic apoptosis and necrosis in pathogenesis of liver diseases. Apoptosis and necrosis represent alternative outcomes of different etiology during liver injury. Apoptosis is a main mode of cell death in chronic viral hepatitis, but is intermingled with necrosis in cholestatic livers. Necrosis is the principal type of liver cell killing in acetaminophen-induced hepatotoxicity. Anti-apoptosis as a strategy is beneficial to liver repair response. Therapeutic options of liver disease depend on the understanding toward pathogenic mechanisms of different etiology. Copyright © 2014 Elsevier GmbH. All rights reserved.

  3. Methoxyflavone derivatives modulate the effect of TRAIL-induced apoptosis in human leukemic cell lines

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    Wudtiwai Benjawan

    2011-12-01

    Full Text Available Abstract Background Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL induces apoptosis in various tumor cells, but does not affect normal cells or human leukemic cells, such as MOLT-4 and U937 cells, which are relatively resistant to TRAIL. Three flavonoids extracted from the rhizome of K. parviflora were 5,7-dimethoxyflavone (DMF, 5,7,4'-trimethoxyflavone (TMF and 3,5,7,3',4'-pentamethoxyflavone (PMF, and synthetic flavonoids including 5-methoxyflavone (5-MF and 2'-methoxyflavone (2"-MF were chosen for testing in this study. The aims of this study were to examine whether the treatment of TRAIL-resistant leukemia MOLT-4 and U937 cells, with methoxyflavone derivatives could enhance the apoptotic response and to identify the mechanism involved. Methods The cytotoxic effect of methoxyflavone (MF derivatives in MOLT-4, U937 and peripheral blood mononuclear cells (PBMCs was analyzed by the MTT assay. The induction of apoptosis and the reduction of mitochondrial transmembrane potential (ΔΨm after staining with annexin V FITC and propidium iodide (PI, and 3,3'-dihexyloxacarbocyanine iodide (DiOC6, respectively, were performed using flow cytometry. ROS production was determined by staining with 2',7'-dichlorofluorescin diacetate and processed with a flow cytometer. DR4, DR5, cFLIP, Mcl-1, BAX and Bid expression were demonstrated by immunoblotting. Caspase-8 and -3 activities were determined by using IETD-AFC and DEVD-AFC substrates and the fluorescence intensity was measured. Results All methoxyflavone derivatives were cytotoxic to MOLT-4, U937 cells and PBMCs, except DMF, TMF and PMF were not toxic to PBMCs. All MF derivatives induced human leukemic MOLT-4 cell apoptosis, but not in U937 cells. Percentage of MOLT-4 cells with (ΔΨm was increased when treated with DMF, TMF, PMF, 5-MF and 2'-MF in the presence of TRAIL. 5-MF and 2'-MF enhanced TRAIL-induced apoptosis through the up-regulation of both DRs and the down-regulation of c

  4. Alcohol and Apoptosis: Friends or Foes?

    Science.gov (United States)

    Rodriguez, Ana; Chawla, Karan; Umoh, Nsini A; Cousins, Valerie M; Ketegou, Assama; Reddy, Madhumati G; AlRubaiee, Mustafa; Haddad, Georges E; Burke, Mark W

    2015-11-19

    Alcohol abuse causes 79,000 deaths stemming from severe organ damage in the United States every year. Clinical manifestations of long-term alcohol abuse on the cardiac muscle include defective contractility with the development of dilated cardiomyopathy and low-output heart failure; which has poor prognosis with less than 25% survival for more than three years. In contrast, low alcohol consumption has been associated with reduced risk of cardiovascular disease, however the mechanism of this phenomenon remains elusive. The aim of this study was to determine the significance of apoptosis as a mediating factor in cardiac function following chronic high alcohol versus low alcohol exposure. Adult rats were provided 5 mM (low alcohol), 100 mM (high alcohol) or pair-fed non-alcohol controls for 4-5 months. The hearts were dissected, sectioned and stained with cresyl violet or immunohistochemically for caspase-3, a putative marker for apoptosis. Cardiomyocytes were isolated to determine the effects of alcohol exposure on cell contraction and relaxation. High alcohol animals displayed a marked thinning of the left ventricular wall combined with elevated caspase-3 activity and decreased contractility. In contrast, low alcohol was associated with increased contractility and decreased apoptosis suggesting an overall protective mechanism induced by low levels of alcohol exposure.

  5. Lipid Metabolism, Apoptosis and Cancer Therapy

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    Chunfa Huang

    2015-01-01

    Full Text Available Lipid metabolism is regulated by multiple signaling pathways, and generates a variety of bioactive lipid molecules. These bioactive lipid molecules known as signaling molecules, such as fatty acid, eicosanoids, diacylglycerol, phosphatidic acid, lysophophatidic acid, ceramide, sphingosine, sphingosine-1-phosphate, phosphatidylinositol-3 phosphate, and cholesterol, are involved in the activation or regulation of different signaling pathways. Lipid metabolism participates in the regulation of many cellular processes such as cell growth, proliferation, differentiation, survival, apoptosis, inflammation, motility, membrane homeostasis, chemotherapy response, and drug resistance. Bioactive lipid molecules promote apoptosis via the intrinsic pathway by modulating mitochondrial membrane permeability and activating different enzymes including caspases. In this review, we discuss recent data in the fields of lipid metabolism, lipid-mediated apoptosis, and cancer therapy. In conclusion, understanding the underlying molecular mechanism of lipid metabolism and the function of different lipid molecules could provide the basis for cancer cell death rationale, discover novel and potential targets, and develop new anticancer drugs for cancer therapy.

  6. Control of apoptosis by asymmetric cell division.

    Science.gov (United States)

    Hatzold, Julia; Conradt, Barbara

    2008-04-08

    Asymmetric cell division and apoptosis (programmed cell death) are two fundamental processes that are important for the development and function of multicellular organisms. We have found that the processes of asymmetric cell division and apoptosis can be functionally linked. Specifically, we show that asymmetric cell division in the nematode Caenorhabditis elegans is mediated by a pathway involving three genes, dnj-11 MIDA1, ces-2 HLF, and ces-1 Snail, that directly control the enzymatic machinery responsible for apoptosis. Interestingly, the MIDA1-like protein GlsA of the alga Volvox carteri, as well as the Snail-related proteins Snail, Escargot, and Worniu of Drosophila melanogaster, have previously been implicated in asymmetric cell division. Therefore, C. elegans dnj-11 MIDA1, ces-2 HLF, and ces-1 Snail may be components of a pathway involved in asymmetric cell division that is conserved throughout the plant and animal kingdoms. Furthermore, based on our results, we propose that this pathway directly controls the apoptotic fate in C. elegans, and possibly other animals as well.

  7. Control of apoptosis by asymmetric cell division.

    Directory of Open Access Journals (Sweden)

    Julia Hatzold

    2008-04-01

    Full Text Available Asymmetric cell division and apoptosis (programmed cell death are two fundamental processes that are important for the development and function of multicellular organisms. We have found that the processes of asymmetric cell division and apoptosis can be functionally linked. Specifically, we show that asymmetric cell division in the nematode Caenorhabditis elegans is mediated by a pathway involving three genes, dnj-11 MIDA1, ces-2 HLF, and ces-1 Snail, that directly control the enzymatic machinery responsible for apoptosis. Interestingly, the MIDA1-like protein GlsA of the alga Volvox carteri, as well as the Snail-related proteins Snail, Escargot, and Worniu of Drosophila melanogaster, have previously been implicated in asymmetric cell division. Therefore, C. elegans dnj-11 MIDA1, ces-2 HLF, and ces-1 Snail may be components of a pathway involved in asymmetric cell division that is conserved throughout the plant and animal kingdoms. Furthermore, based on our results, we propose that this pathway directly controls the apoptotic fate in C. elegans, and possibly other animals as well.

  8. Keratinocyte Apoptosis is Decreased in Psoriatic Epidermis

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    Fatma Eskioğlu

    2009-12-01

    Full Text Available Background and Design: Abnormal differentiation and hyperproliferation of keratinocytes are the hallmarks of psoriasis vulgaris. Although psoriasis vulgaris is generally accepted as a disease of decreased keratinocyte apoptosis, the results are contradictory. The aim of the current study is to investigate whether decreased keratinocyte apoptosis contributes to the formation of a thickened epidermis as increased keratinocyte proliferation. Material and Method: Forty-three untreated psoriasis vulgaris patients and 20 healthy control subjects were included into the study. Biopsy specimens taken from the enrollee were evaluated by immunohistochemical staining for Ki-67 expressions to show the proliferation of keratinocytes and by the terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling (TUNEL method to show the apoptotic keratinocytes. Results: Apoptotic index (percentage of the TUNEL positive cells was significantly lower in psoriatic epidermis (0.33±0.64 than in normal epidermis (0.75±0.85; whereas Ki-67 index (percentage of positively staining cells for Ki-67 was significantly higher in psoriatic epidermis (30.86±10.49 than in normal epidermis (11.65±2.98, (p=0.021 and p=0.00; respectively. Conclusion: Decreased keratinocyte apoptosis also contribute to increased epidermal thickness in psoriasis as well as increased keratinocyte proliferation.

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

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    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.

  10. Pycnogenol Induces Nuclear Translocation of Apoptosis-inducing Factor and Caspase-independent Apoptosis in MC-3 Human Mucoepidermoid Carcinoma Cell Line.

    Science.gov (United States)

    Yang, In-Hyoung; Shin, Ji-Ae; Cho, Sung-Dae

    2014-12-01

    Pycnogenol is extracted from the pine bark of a tree known as Pinus pinaster that has variety biological effects. However, its anticancer activity has not yet been completely studied. The aim of this study is to investigate anticancer effect of pycnogenol in MC-3 human mucoepidermoid carcinoma (MEC) cell line. We describe the effect of anti-cancer of pycnogenol in MC-3 human oral MEC cells using trypan blue exclusion assay, 3-(4,5-dimethylthiazol-2-yl)-(3-carboxymethoxyphenyl)-2-(4-sulphophenyl)-2H-tetrazolium (MTS) assay, Western blot, preparation of cytosolic and nuclear fractions, immunocytochemistry and reverse transcriptase polymerase chain reaction. Pycnogenol significantly decreased cell viability and also induced caspase-independent apoptosis. We confirmed that pycnogenol induced the translocation of apoptosis-inducing factor into nucleus and regulated apoptosis. Also, Bak protein stability was partly enhanced by pycnogenol to elevate the expression level of Bak protein. Overall, pycnogenol may be a fascinating therapeutic drug candidate for the treatment of MEC.

  11. Spironolactone induces apoptosis in human mononuclear cells. Association between apoptosis and cytokine suppression

    DEFF Research Database (Denmark)

    Mikkelsen, Martin; Sønder, S U; Nersting, J

    2006-01-01

    Spironolactone (SPIR) has been described to suppress accumulation of pro-inflammatory cytokines. Here, the suppression of TNF-alpha in lipopolysaccharide (LPS)-stimulated mononuclear cell cultures was confirmed. However, SPIR was also found to induce apoptosis, prompting the investigations...... of a possible association between the two effects: The apoptosis-inducing and the cytokine-suppressive effects of SPIR correlated with regard to the effective concentration range. Also, pre-incubation experiments demonstrated a temporal separation of the two effects of ... preceding apoptosis. An association between the two effects was also seen when testing several SPIR analogues. Contrary to TNF-alpha, the levels of IL-1beta increased in SPIR-treated cultures. However, the amount of IL-1beta in the supernatants depended upon the order of SPIR and LPS addition, as IL-1beta...

  12. Selenium Inhibits Homocysteine-Induced Endothelial Dysfunction and Apoptosis via Activation of AKT

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    Hui Ren

    2016-02-01

    Full Text Available Background/Aims: Endothelial cells are crucial in vascular homeostasis. Dysfunction of endothelial cells is involved in the development of cardiovascular diseases (CVD. High plasma homocysteine (Hcy correlates with CVD while selenium supplementation counteracts development of CVD. However, the underlying mechanism remained unclear. Here, we investigated the effects of selenium on homocysteine-induced endothelial dysfunction. Methods: An animal model of Hcy-induced endothelial dysfunction was established by intragastric administration of L-methionine. Plasma NO and von Willebrand factor (vWF were quantified using NO assay and ELISA kit respectively. Relaxation was measured in thoracic aortic ring assays. Cell viability and migration were detected by Cell Counting Kit-8 and Bio-Coat cell migration chambers respectively. Cellular apoptosis was determined by Annexin V-FITC apoptosis kit. Results: Selenium prevented homocysteine-induced endothelial injury and impairment of endothelium-dependent relaxation. Selenium reversed the impaired viability and migration of endothelial cells induced by homocysteine in a dose-dependent manner. Selenium inhibited the apoptosis of endothelial cells induced by homocysteine, through downregulating of Caspase-3 activity and expression of Caspase-3 and Bax, and by stimulating Bcl-2 expression. Selenium reversed the homocysteine-induced reduction of NO release, and increased the expression and phosphoylation of endothelial nitric oxide synthetase (eNOS in a dose-dependent manner. Moreover, selenium enhanced AKT phosphorylation, and selenium-induced phosphorylation and expression of eNOS were inhibited by AKT inhibition. NO production, cell viability and migration rescued by selenium were inhibited, while cell apoptosis was reversed by AKT inhibition. Conclusion: Selenium protected against homocysteine-induced dysfunction and apoptosis of endothelial cells through AKT pathway. The observations may provide novel

  13. Autophagy protects meniscal cells from glucocorticoids-induced apoptosis via inositol trisphosphate receptor signaling.

    Science.gov (United States)

    Shen, Chao; Gu, Wen; Cai, Gui-Quan; Peng, Jian-Ping; Chen, Xiao-Dong

    2015-09-01

    Intra-articular injection of glucocorticoids (GCs) has been widely used in the management of osteoarthritis and rheumatoid arthritis. Nevertheless, several studies showed that GCs had toxic effects on chondrocytes as well as synovial cells. Previously we reported the protective role of autophagy in the degeneration of meniscal tissues. However, the effects of GCs on autophagy in the meniscal cells have not been fully elucidated. To investigate whether GCs can regulate autophagy in human meniscal cells, the meniscal cells were cultured in vitro and exposed in the presence of dexamethasone. The levels of apoptosis and autophagy were investigated via flow cytometry as well as western blotting analysis. The changes of the aggrecanases were measured using real-time PCR. The role of autophagy in dexamethasone-induced apoptosis was investigated using pharmacological agents and RNA interference technique. An agonist of inositol 1,4,5-trisphosphate receptor (IP3R) was used to investigate the mechanism of dexamethasone-induced autophagy. The results showed that dexamethasone induced autophagy as well as apoptosis in normal human meniscal cells. Using RNA interference technique and pharmacological agents, our results showed that autophagy protected the meniscal cells from dexamethasone-induced apoptosis. Our results also indicated that dexamethasone increased the mRNA levels of aggrecanases. This catabolic effect of dexamethasone was enhanced by 3-MA, the autophagy inhibitor. Furthermore, our results showed that dexamethasone induced autophagy via suppressing the phosphorylation of IP3R. In summary, our results indicated that autophagy protected meniscal cells from GCs-induced apoptosis via inositol trisphosphate receptor signaling.

  14. Role of NgR mediated oxidative stress in glucose induced RGC apoptosis

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    Yu-Bo Wang

    2017-02-01

    Full Text Available AIM: To investigate the effect of NgR mediated oxidative stress on the apoptosis of retinal ganglion cells(RGCsinduced by glucose. METHODS: RGC-5 cell were divided into 3 groups: control group(DMEM high glucose medium+10% fetal calf serum, high glucose group(DMEM high glucose medium+10% fetal calf serum+30mmol/L glucose,NEP1-40 group(DMEM high glucose medium+10% fetal calf serum+30mmol/L glucose+1μmol/L NEP1-40. Detections were performed after 3d culture: the state of cell growth was observed by microscopy. Cell viability was detected by CCK-8 kit. The apoptosis rate of RGC cells was detected by flow cytometry(FCM. The intensity of ROS of the cells were detected by fluorescence microscopy. Intracellular MDA levels and SOD activity were measured by related kits. Western blot was used to detect the expressions of Bcl-2 and Bax proteins. RESULTS: Compared with control group, high glucose group had a poor state and cell viability decreased, cell apoptosis rate significantly increased, ROS and MDA levels were significantly enhanced, SOD activity decreased, and the expression of anti-apoptotic protein Bcl-2 was decreased and the expression of pro apoptotic protein Bax was up-regulated. Compared with glucose group, after NgR expression was inhibited by NEP1-40, the oxidative stress reaction was reduced, Bcl-2/Bax was increased, the cell status was improved, the cell viability was increased, and the apoptosis rate was decreased in the NEP1-40 group(PCONCLUSION: High concentration of glucose can induce apoptosis of RGC-5 cells by NgR mediated oxidative stress reaction.

  15. Induction of eosinophil apoptosis by hydrogen peroxide promotes the resolution of allergic inflammation

    Science.gov (United States)

    Reis, A C; Alessandri, A L; Athayde, R M; Perez, D A; Vago, J P; Ávila, T V; Ferreira, T P T; de Arantes, A CS; de Sá Coutinho, D; Rachid, M A; Sousa, L P; Martins, M A; Menezes, G B; Rossi, A G; Teixeira, M M; Pinho, V

    2015-01-01

    Eosinophils are effector cells that have an important role in the pathogenesis of allergic disease. Defective removal of these cells likely leads to chronic inflammatory diseases such as asthma. Thus, there is great interest in understanding the mechanisms responsible for the elimination of eosinophils from inflammatory sites. Previous studies have demonstrated a role for certain mediators and molecular pathways responsible for the survival and death of leukocytes at sites of inflammation. Reactive oxygen species have been described as proinflammatory mediators but their role in the resolution phase of inflammation is poorly understood. The aim of this study was to investigate the effect of reactive oxygen species in the resolution of allergic inflammatory responses. An eosinophilic cell line (Eol-1) was treated with hydrogen peroxide and apoptosis was measured. Allergic inflammation was induced in ovalbumin sensitized and challenged mouse models and reactive oxygen species were administered at the peak of inflammatory cell infiltrate. Inflammatory cell numbers, cytokine and chemokine levels, mucus production, inflammatory cell apoptosis and peribronchiolar matrix deposition was quantified in the lungs. Resistance and elastance were measured at baseline and after aerosolized methacholine. Hydrogen peroxide accelerates resolution of airway inflammation by induction of caspase-dependent apoptosis of eosinophils and decrease remodeling, mucus deposition, inflammatory cytokine production and airway hyperreactivity. Moreover, the inhibition of reactive oxygen species production by apocynin or in gp91phox−/− mice prolonged the inflammatory response. Hydrogen peroxide induces Eol-1 apoptosis in vitro and enhances the resolution of inflammation and improves lung function in vivo by inducing caspase-dependent apoptosis of eosinophils. PMID:25675292

  16. Nrf2 Inhibits Periodontal Ligament Stem Cell Apoptosis under Excessive Oxidative Stress

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    Yanli Liu

    2017-05-01

    Full Text Available The present study aimed to analyze novel mechanisms underlying Nrf2-mediated anti-apoptosis in periodontal ligament stem cells (PDLSCs in the periodontitis oxidative microenvironment. We created an oxidative stress model with H2O2-treated PDLSCs. We used real-time PCR, Western blotting, TUNEL staining, fluorogenic assay and transfer genetics to confirm the degree of oxidative stress and apoptosis as well as the function of nuclear factor-erythroid 2-related factor 2 (Nrf2. We demonstrated that with upregulated levels of reactive oxygen species (ROS and malondialdehyde (MDA, the effect of oxidative stress was obvious under H2O2 treatment. Oxidative molecules were altered after the H2O2 exposure, whereby the signaling of Nrf2 was activated with an increase in its downstream effectors, heme oxygenase-1 (HO-1, NAD(PH:quinone oxidoreductase 1 (NQO1 and γ-glutamyl cysteine synthetase (γ-GCS. Additionally, the apoptosis levels gradually increased with oxidative stress by the upregulation of caspase-9, caspase-3, Bax and c-Fos levels in addition to the downregulation of Bcl-2. However, there was no alterations in levels of caspase-8. The enhanced antioxidant effect could not mitigate the occurrence of apoptosis. Furthermore, Nrf2 overexpression effectively improved the anti-oxidative levels and increased cell proliferation. At the same time, overexpression effectively restrained TUNEL staining and decreased the molecular levels of caspase-9, caspase-3, Bax and c-Fos, but not that of caspase-8. In contrast, silencing the expression of Nrf2 levels had the opposite effect. Collectively, Nrf2 alleviates PDLSCs via its effects on regulating oxidative stress and anti-intrinsic apoptosis by the activation of oxidative enzymes.

  17. Artesunate induces ROS-mediated apoptosis in doxorubicin-resistant T leukemia cells.

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    Thomas Efferth

    Full Text Available BACKGROUND: A major obstacle for successful cancer treatment often is the development of drug resistance in cancer cells during chemotherapy. Therefore, there is an urgent need for novel drugs with improved efficacy against tumor cells and with less toxicity on normal cells. Artesunate (ART, a powerful anti-malarial herbal compound, has been shown to inhibit growth of various tumor cell lines in vitro and of xenografted Kaposi's sarcoma in mice in vivo. However, the molecular mechanisms by which ART exerts its cytotoxicity have not been elucidated. The ART-class of anti-malarial compounds is attractive due to their activity against multidrug-resistant Plasmodium falciparum and Plasmodium vivax strains. Another salient feature of these compounds is the lack of severe side effects in malaria patients. METHODOLOGY AND PRINCIPAL FINDINGS: In this study, we used T-cell leukemias as a model system to study the molecular mechanisms of ART-induced apoptosis. The most typical anticancer drugs are DNA intercalators such as Doxorubicin. To investigate drug sensitivity and resistance, we chose a Doxorubicin-resistant leukemia cell line and investigated the killing effect of ART on these cells. We show that ART induces apoptosis in leukemic T cells mainly through the mitochondrial pathway via generation of reactive oxygen species (ROS, a mechanism different from Doxorubicin. This is confirmed by the fact that the antioxidant N-Acetyle-Cysteine (NAC could completely block ROS generation and, consequently, inhibited ART-induced apoptosis. Therefore, ART can overcome the Doxorubicin-resistance and induce the Doxorubicin-resistant leukemia cells to undergo apoptosis. We also show that ART can synergize with Doxorubicin to enhance apoptotic cell death in leukemic T cells. This synergistic effect can be largely explained by the fact that ART and Doxorubicin use different killing mechanisms. CONCLUSIONS: Our studies raise the possibility to develop ART in

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

    Energy Technology Data Exchange (ETDEWEB)

    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

  19. Cholesterol exacerbates Mycoplasma hyopneumoniae-induced apoptosis via stimulating proliferation and adhesion to porcine alveolar macrophages.

    Science.gov (United States)

    Liu, Maojun; Du, Gaimei; Liu, Beibei; Hu, Yun; Liu, Jie; Jia, Yimin; Minion, F Chris; Shao, Guoqing; Zhao, Ruqian

    2017-11-01

    Mycoplasma hyopneumoniae (M. hyo) is the agent of porcine enzootic pneumonia, a disease that causes considerable economic losses in the swine industry. Induction of apoptosis in porcine alveolar macrophages is an important pathogenic mechanism of M. hyo. Cholesterol has been reported to influence cell adherence and cell invasion of Mycoplasma gallisepticum and Mycoplasma fermentans leading to apoptosis, but the role of cholesterol on the apoptotic inducing activity of M. hyo remains unknown. In this study, we found a positive correlation between cholesterol level and M. hyo infection in porcine serum and lung tissue. Cholesterol exacerbated M. hyo-induced apoptosis in porcine alveolar macrophages (PAMs) in a dosage-dependent manner, which was associated with increased hydrogen peroxide (H2O2) and nitric oxide (NO) production, up-regulated TNF-α mRNA expression, and activated caspase-3. The pathogenicity-enhancing effect of cholesterol was related to increased M. hyo proliferation with an up-regulation of M. hyo genes responsible for DNA and protein synthesis, which led to improved M. hyo adherence to PAMs, presumably via increased mRNA expression of adhesin genes. In conclusion, cholesterol promotes the apoptotic effect of M. hyo through stimulating proliferation and enhancing its adherence to PAMs. Hence, the study gives new insights into the role of cholesterol on the PAM - M. hyo interations. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Ganoderma atrum polysaccharide ameliorates ROS generation and apoptosis in spleen and thymus of immunosuppressed mice.

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    Li, Wen-Juan; Li, Lu; Zhen, Weng-Ya; Wang, Le-Feng; Pan, Meng; Lv, Jia-Qian; Wang, Fan; Yao, Yu-Fei; Nie, Shao-Ping; Xie, Ming-Yong

    2017-01-01

    Ganoderma atrum polysaccharide (PSG-1) is a bioactive compound with antioxidant and immunomodulatory activities. The aim of this study was to determine the effect of PSG-1 on reactive oxygen species (ROS) generation and apoptosis in spleen and thymus of cyclophosphamide (CTX)-induced immunosuppressed mice. The results showed that PSG-1 protected mice against CTX-mediated immunosuppression, as evidenced by enhancing the ratios of thymus and spleen weights to body weight, promoting T cell and B cell survival, and increasing levels of TNF-α and IL-2. Apoptosis, ROS generation and lipid peroxidation in the immune organs of the immunosuppressed animals were ameliorated by PSG-1. The immune benefits of PSG-1 were associated with the enhancement of the activities of glutathione peroxidase, superoxide dismutase and catalase in the immune organs, implying that antioxidant activities of PSG-1 may play an important role in PSG-1-evoked immune protection. Taken together, these findings have demonstrated that PSG-1 may ameliorate CTX-induced immunosuppression through reducing apoptosis and oxidative damage in immunological system. Copyright © 2016. Published by Elsevier Ltd.

  1. Flavopiridol induces cellular FLICE-inhibitory protein degradation by the proteasome and promotes TRAIL-induced early signaling and apoptosis in breast tumor cells.

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    Palacios, Carmen; Yerbes, Rosario; López-Rivas, Abelardo

    2006-09-01

    The cyclin-dependent kinase inhibitor flavopiridol is undergoing clinical trials as an antitumor drug. We show here that pretreatment of different human breast cancer cell lines with flavopiridol facilitates tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-induced apoptosis. In breast tumor cells, apoptosis induction by TRAIL is blocked at the level of apical caspase-8 activation. Flavopiridol treatment enhances TRAIL-induced formation of death-inducing signaling complex and early processing of procaspase-8. Subsequently, a TRAIL-induced, mitochondria-operated pathway of apoptosis is activated in cells treated with flavopiridol. Down-regulation of cellular FLICE-inhibitory proteins (c-FLIP; c-FLIP(L) and c-FLIP(S)) is observed on flavopiridol treatment. c-FLIP loss and apoptosis sensitization by flavopiridol are both prevented in cells treated with an inhibitor of the ubiquitin-proteasome system. Furthermore, targeting c-FLIP directly with small interfering RNA oligonucleotides also sensitizes various human breast tumor cell lines to TRAIL-induced apoptosis. Our results indicate that flavopiridol sensitizes breast cancer cells to TRAIL-induced apoptosis by facilitating early events in the apoptotic pathway, and this combination treatment could be regarded as a potential therapeutic tool against breast tumors.

  2. Requirement of Nuclear Factor κB for Smac Mimetic–Mediated Sensitization of Pancreatic Carcinoma Cells for Gemcitabine-Induced Apoptosis

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    Dominic Stadel

    2011-12-01

    Full Text Available Defects in apoptosis contribute to treatment resistance and poor outcome of pancreatic cancer, calling for novel therapeutic strategies. Here, we provide the first evidence that nuclear factor (NF κB is required for Smac mimetic– mediated sensitization of pancreatic carcinoma cells for gemcitabine-induced apoptosis. The Smac mimetic BV6 cooperates with gemcitabine to reduce cell viability and to induce apoptosis. In addition, BV6 significantly enhances the cytotoxicity of several anticancer drugs against pancreatic carcinoma cells, including doxorubicin, cisplatin, and 5-fluorouracil. Molecular studies reveal that BV6 stimulates NF-κB activation, which is further increased in the presence of gemcitabine. Importantly, inhibition of NF-κB by overexpression of the dominant-negative IκBα superrepressor significantly decreases BV6- and gemcitabine-induced apoptosis, demonstrating that NF-κB exerts a proapoptotic function in this model of apoptosis. In support of this notion, inhibition of tumor necrosis factor α (TNFα by the TNFα blocking antibody Enbrel reduces BV6- and gemcitabine-induced activation of caspase 8 and 3, loss of mitochondrial membrane potential, and apoptosis. By demonstrating that BV6 and gemcitabine trigger a NF-κB–dependent, TNFα-mediated loop to activate apoptosis signaling pathways and caspase-dependent apoptotic cell death, our findings have important implications for the development of Smac mimetic–based combination protocols in the treatment of pancreatic cancer.

  3. Sex differences play a role in cardiac endoplasmic reticulum stress (ERS) and ERS-initiated apoptosis induced by pressure overload and thapsigargin.

    Science.gov (United States)

    Sari, Flori R; Watanabe, Kenichi; Widyantoro, Bambang; Thandavarayan, Rajarajan A; Harima, Meilei; Kodama, Makoto; Aizawa, Yoshifusa

    2011-01-01

    Excessive endoplasmic reticulum stress (ERS) triggers myocardial apoptosis. Sex differences appear to be an important determinant in the occurrence of stress and apoptosis through many pathways, but the roles of sex differences in the cardiac ERS and ERS-initiated apoptosis are largely unknown. In the present study, we investigated the in vivo role of sex differences in the cardiac ERS and apoptosis elicited by ascending aortic banding surgery or thapsigargin (Thap) injection using male and female C57BL/6 JAX mice. The surgery significantly increased the expression levels of cardiac glucose-regulated protein (GRP)78 and CCAAT/enhancer binding protein homology protein (CHOP) protein, increased the myocardial apoptosis and decreased the sarcoplasmic reticulum Ca(2+)-ATPase isoform (SERCA)2 immunoreactivity in the male mice relative to female mice. Furthermore, during ERS induction using Thap, myocardial apoptosis and the expression levels of cardiac GRP78, inositol-requiring enzyme (Ire)1α and tumor necrosis factor receptor-associated factor (TRAF)2 were significantly increased in male mice relative to female mice. Sex differences significantly affected the above results. Our data suggest that sex differences affected the response of myocardial tissues in dealing with cardiac ERS and further result of ERS, apoptosis, at least in part through the regulation of SERCA2, CHOP, Ire1α and TRAF2. Copyright © 2011. Published by Elsevier Inc.

  4. Ethanol extract of Brazilian red propolis induces apoptosis in human breast cancer MCF-7 cells through endoplasmic reticulum stress.

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    Kamiya, Tetsuro; Nishihara, Hiroko; Hara, Hirokazu; Adachi, Tetsuo

    2012-11-07

    Propolis, a natural product collected from plants by honey bees, is commonly used in folk medicines. Endoplasmic reticulum (ER) stress is known to induce apoptosis through the induction of CCAAT/enhancer-binding protein homologous protein (CHOP). Here, we investigated whether ethanol extracts of propolis and caffeic acid phenethyl ester (CAPE) induce apoptosis, mitochondrial dysfunction, and ER stress in human breast cancer MCF-7 cells and human fibroblasts. Among several ethanol extracts of propolis and CAPE, Brazilian red propolis (BRP) significantly reduced MCF-7 cell viability through the induction of mitochondrial dysfunction, caspase-3 activity, and DNA fragmentation but did not affect those of fibroblasts. Moreover, treatment with BRP significantly induced CHOP expression in MCF-7 cells compared to fibroblasts. Further, pretreatment with a chemical chaperone, 4-phenylbutyric acid, suppressed BRP-triggered MCF-7 cell death. Overall, we revealed that an ethanol extract of BRP induces MCF-7 cell apoptosis through, at least in part, ER stress-related signaling.

  5. Time-Dependent Regulation of Apoptosis by AEN and BAX in Response to 2-Aminoanthracene Dietary Consumption.

    Science.gov (United States)

    Gato, Worlanyo Eric; McGee, Stacey R; Hales, Dale B; Means, Jay C

    2014-01-01

    The modulation of the toxic effects of 2-aminoanthracene (2AA) on the liver by apoptosis was investigated. Fisher-344 (F344) rats were exposed to various concentrations of 2AA for 14 and 28 days. The arylamine 2AA is an aromatic hydrocarbon employed in manufacturing chemicals, dyes, inks, and it is also a curing agent in epoxy resins and polyurethanes. 2AA has been detected in tobacco smoke and cooked foods. Analysis of total messenger ribonucleic acid (mRNA) extracts from liver for apoptosis-related gene expression changes in apoptosis enhancing nuclease (AEN), Bcl2-associated X protein (BAX), CASP3, Jun proto-oncogene (JUN), murine double minute-2 p53 binding protein homolog (MDM2), tumor protein p53 (p53), and GAPDH genes by quantitative real-time polymerase chain reaction (qRT-PCR) was coupled with terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) and caspase-3 (Casp3) activity assays. Specific apoptosis staining result does not seem to show significant difference between control and treated animals. This may be due to freeze-thaw artifacts observed in the liver samples. However, there appears to be a greater level of apoptosis in medium- and high-dose (MD and HD) 2AA treated animals. Analyses of apoptosis-related genes seem to show AEN and BAX as the main targets in the induction of apoptosis in response to 2AA exposure, though p53, MDM2, and JUN may play supporting roles. Dose-dependent increases in mRNA expression were observed in all genes except Casp3. BAX was very highly expressed in the HD rats belonging to the 2-week exposure group. This trend was not observed in the animals treated for 4 weeks. Instead, AEN was rather very highly expressed in the liver of the MD animals that were treated with 2AA for 28 days.

  6. Inflammatory cytokine TNF-α promotes corneal endothelium apoptosis via upregulating TIPE2 transcription during corneal graft rejection.

    Science.gov (United States)

    Wang, Qun; Wei, Chao; Ma, Li; Wang, Xin; Li, Lin; Zhou, Qingjun; Shi, Weiyun

    2018-02-26

    Endothelial dysfunction accounts for 50% of total corneal transplantation failures, suggesting that corneal endothelial damage is the leading cause of graft failure. Tumor necrosis factor-α (TNF-α) is known to contribute to the negative regulation of corneal transplantation, but how it does so remains unclear. Here, we report a regulatory loop involving TNF-α, TNF-α-induced protein 8 like 2 (TNFAIP8L2 or TIPE2), and apoptosis during corneal graft rejection. We established mice models of penetrating keratoplasty to verify whether the quantification of TNF-α in allogeneic corneas is enhanced through ELISA assay and immunofluorescence staining. In cornea tissues, we obtained corneal endothelium and measured apoptosis of the removed cells. Meanwhile, quantitative real-time PCR and Western blotting were used to detect the mRNA and protein expression of TIPE2. In human corneal endothelial cells, we verified the conclusions through some experiments. By specifically knocking down TIPE2, we detected the importance of TIPE2 in TNF-α-triggered apoptosis. In mice models, TNF-α was higher in the cornea and aqueous humor in allograft group and TNF-α elevation increased the apoptosis of the corneal endothelium. In addition, high levels of TIPE2 were found in allograft rejection models following TNF-α elevation. In human corneal endothelial cells (HCECs), TNF-α clearly augments TIPE2 expression and promotes cell apoptosis through upregulating TIPE2 transcription. Knocking down markedly decreased cell apoptosis. Our study identifies the molecular mechanisms underlying the interplay of TNF-α, TIPE2, and apoptosis during allograft rejection, and it suggests that both TNF-α and TIPE2 might be potential targets for the successfully grafted corneal endothelium.

  7. Mechanical and hypoxia stress can cause chondrocytes apoptosis through over-activation of endoplasmic reticulum stress.

    Science.gov (United States)

    Huang, Ziwei; Zhou, Min; Wang, Qian; Zhu, Mengjiao; Chen, Sheng; Li, Huang

    2017-12-01

    To examine the role of mechanical force and hypoxia on chondrocytes apoptosis and osteoarthritis (OA)-liked pathological change on mandibular cartilage through over-activation of endoplasmic reticulum stress (ERS). We used two in vitro models to examine the effect of mechanical force and hypoxia on chondrocytes apoptosis separately. The mandibular condylar chondrocytes were obtained from three-week-old male Sprague-Dawley rats. Flexcell 5000T apparatus was used to produce mechanical forces (12%, 0.5Hz, 24h vs 20%, 0.5Hz, 24h) on chondrocytes. For hypoxia experiment, the concentration of O 2 was down regulated to 5% or 1%. Cell apoptosis rates were quantified by annexin V and propidium iodide (PI) double staining and FACS analysis. Quantitative real-time PCR and western blot were performed to evaluate the activation of ERS and cellular hypoxia. Then we used a mechanical stress loading rat model to verify the involvement of ERS in OA-liked mandibular cartilage pathological change. Histological changes in mandibular condylar cartilage were assessed via hematoxylin & eosin (HE) staining. Immunohistochemistry of GRP78, GRP94, HIF-1α, and HIF-2α were performed to evaluate activation of the ERS and existence of hypoxia. Apoptotic cells were detected by the TUNEL method. Tunicamycin, 20% mechanical forces and hypoxia (1% O 2 ) all significantly increased chondrocytes apoptosis rates and expression of ERS markers (GRP78, GRP94 and Caspase 12). However, 12% mechanical forces can only increase the apoptotic sensitivity of chondrocytes. Mechanical stress resulted in OA-liked pathological change on rat mandibular condylar cartilage which included thinning cartilage and bone erosion. The number of apoptotic cells increased. ERS and hypoxia markers expressions were also enhanced. Salubrinal, an ERS inhibitor, can reverse these effects in vitro and in vivo through the down-regulation of ERS markers and hypoxia markers. We confirmed that mechanical stress and local hypoxia both

  8. Induction of Apoptosis by Functionalized Fullerene-based Sonodynamic Therapy in HL-60 cells.

    Science.gov (United States)

    Yumita, Nagahiko; Watanabe, Takahiro; Chen, Fu-Shih; Momose, Yasunori; Umemura, Shin-Ichiro

    2016-06-01

    Ultrasound has been widely utilized for medical diagnosis and therapy due to its ability to penetrate deep-seated tissue with less attenuation of energy and minimal undesirable side-effects. Functionalized fullerenes, such as polyhydroxy fullerene (PHF), have attracted particular attention due to their water solubility and potential application in tumor imaging and therapy as carbon nanomaterials. The present study investigated sonodynamically-induced apoptosis using PHF. Cell suspensions were treated with 2-MHz continuous ultrasound in the presence of PHF for 3 min and apoptosis was assessed by cell morphology using confocal microscopy, fragmentation of DNA (ladder pattern after agarose-gel electrophoresis) and caspase-3 activation. Cells were ultrasound-irradiated from the bottom of the culture dishes under the following condition: frequency, 2 MHz; output power, 3 W/cm(2) Electron spin resonance was used to measure reactive oxygen species. The number of apoptotic cells after sonodynamic exposure (ultrasound and PHF) was significantly higher than produced from other treatments, such as ultrasound alone and PHF alone. Furthermore, DNA fragmentation, caspase-3 activation and enhanced 2,2,6,6-tetramethyl-4-piperidinyloxy (4oxoTEMPO) formation were observed in the sonodynamically-treated cells. Histidine, a well-known reactive oxygen scavenger, significantly inhibited sonodynamically-induced apoptosis, caspase-3 activation and 4oxoTEMPO formation. Sonodynamic therapy with PHF induced apoptosis that was characterized by a series of typical morphological features, such as shrinkage of the cell and fragmentation into membrane-bound apoptotic bodies, in HL-60 cells. The significant inhibition of sonodynamically-induced apoptosis, caspase-3 activation, and 4oxoTEMPO formation due to histidine and tryptophan suggests that reactive oxygen species, such as singlet oxygen, are involved in the sonodynamic induction of apoptosis. These findings indicate that PHF

  9. Imiquimod activates p53-dependent apoptosis in a human basal cell carcinoma cell line.

    Science.gov (United States)

    Huang, Shi-Wei; Chang, Shu-Hao; Mu, Szu-Wei; Jiang, Hsin-Yi; Wang, Sin-Ting; Kao, Jun-Kai; Huang, Jau-Ling; Wu, Chun-Ying; Chen, Yi-Ju; Shieh, Jeng-Jer

    2016-03-01

    The tumor suppressor p53 controls DNA repair, cell cycle, apoptosis, autophagy and numerous other cellular processes. Imiquimod (IMQ), a synthetic toll-like receptor (TLR) 7 ligand for the treatment of superficial basal cell carcinoma (BCC), eliminates cancer cells by activating cell-mediated immunity and directly inducing apoptosis and autophagy in cancer cells. To evaluate the role of p53 in IMQ-induced cell death in skin cancer cells. The expression, phosphorylation and subcellular localization of p53 were detected by real-time PCR, luciferase reporter assay, cycloheximide chase analysis, immunoblotting and immunocytochemistry. Using BCC/KMC1 cell line as a model, the upstream signaling of p53 activation was dissected by over-expression of TLR7/8, the addition of ROS scavenger, ATM/ATR inhibitors and pan-caspase inhibitor. The role of p53 in IMQ-induced apoptosis and autophagy was assessed by genetically silencing p53 and evaluated by a DNA content assay, immunoblotting, LC3 puncta detection and acridine orange staining. IMQ induced p53 mRNA expression and protein accumulation, increased Ser15 phosphorylation, promoted nuclear translocation and up-regulated its target genes in skin cancer cells in a TLR7/8-independent manner. In BCC/KMC1 cells, the induction of p53 by IMQ was achieved through increased ROS production to stimulate the ATM/ATR-Chk1/Chk2 axis but was not mediated by inducing DNA damage. The pharmacological inhibition of ATM/ATR significantly suppressed IMQ-induced p53 activation and apoptosis. Silencing of p53 significantly decreased the IMQ-induced caspase cascade activation and apoptosis but enhanced autophagy. Mutant p53 skin cancer cell lines were more resistant to IMQ-induced apoptosis than wildtype p53 skin cancer cell lines. IMQ induced ROS production to stimulate ATM/ATR pathways and contributed to p53-dependent apoptosis in a skin basal cell carcinoma cell line BCC/KMC1. Copyright © 2015 Japanese Society for Investigative Dermatology

  10. Dopamine-induced apoptosis of lactotropes is mediated by the short isoform of D2 receptor.

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    Daniela Betiana Radl

    Full Text Available Dopamine, through D2 receptor (D2R, is the major regulator of lactotrope function in the anterior pituitary gland. Both D2R isoforms, long (D2L and short (D2S, are expressed in lactotropes. Although both isoforms can transduce dopamine signal, they differ in the mechanism that leads to cell response. The administration of D2R agonists, such as cabergoline, is the main pharmacological treatment for prolactinomas, but resistance to these drugs exists, which has been associated with alterations in D2R expression. We previously reported that dopamine and cabergoline induce apoptosis of lactotropes in primary culture in an estrogen-dependent manner. In this study we used an in vivo model to confirm the permissive action of estradiol in the apoptosis of anterior pituitary cells induced by D2R agonists. Administration of cabergoline to female rats induced apoptosis, measured by Annexin-V staining, in anterior pituitary gland from estradiol-treated rats but not from ovariectomized rats. To evaluate the participation of D2R isoforms in the apoptosis induced by dopamine we used lactotrope-derived PR1 cells stably transfected with expression vectors encoding D2L or D2S receptors. In the presence of estradiol, dopamine induced apoptosis, determined by ELISA and TUNEL assay, only in PR1-D2S cells. To study the role of p38 MAPK in apoptosis induced by D2R activation, anterior pituitary cells from primary culture or PR1-D2S were incubated with an inhibitor of the p38 MAPK pathway (SB203850. SB203580 blocked the apoptotic effect of D2R activation in lactotropes from primary cultures and PR1-D2S cells. Dopamine also induced p38 MAPK phosphorylation, determined by western blot, in PR1-D2S cells and estradiol enhanced this effect. These data suggest that, in the presence of estradiol, D2R agonists induce apoptosis of lactotropes by their interaction with D2S receptors and that p38 MAPK is involved in this process.

  11. A cardinal role for cathepsin d in co-ordinating the host-mediated apoptosis of macrophages and killing of pneumococci.

    Directory of Open Access Journals (Sweden)

    Martin A Bewley

    2011-01-01

    Full Text Available The bactericidal function of macrophages against pneumococci is enhanced by their apoptotic demise, which is controlled by the anti-apoptotic protein Mcl-1. Here, we show that lysosomal membrane permeabilization (LMP and cytosolic translocation of activated cathepsin D occur prior to activation of a mitochondrial pathway of macrophage apoptosis. Pharmacological inhibition or knockout of cathepsin D during pneumococcal infection blocked macrophage apoptosis. As a result of cathepsin D activation, Mcl-1 interacted with its ubiquitin ligase Mule and expression declined. Inhibition of cathepsin D had no effect on early bacterial killing but inhibited the late phase of apoptosis-associated killing of pneumococci in vitro. Mice bearing a cathepsin D(-/- hematopoietic system demonstrated reduced macrophage apoptosis in vivo, with decreased clearance of pneumococci and enhanced recruitment of neutrophils to control pulmonary infection. These findings establish an unexpected role for a cathepsin D-mediated lysosomal pathway of apoptosis in pulmonary host defense and underscore the importance of apoptosis-associated microbial killing to macrophage function.

  12. HAMLET kills tumor cells by apoptosis: structure, cellular mechanisms, and therapy.

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    Gustafsson, Lotta; Hallgren, Oskar; Mossberg, Ann-Kristin; Pettersson, Jenny; Fischer, Walter; Aronsson, Annika; Svanborg, Catharina

    2005-05-01

    New cancer treatments should aim to destroy tumor cells without disturbing normal tissue. HAMLET (human alpha-lactalbumin made lethal to tumor cells) offers a new molecular approach to solving this problem, because it induces apoptosis in tumor cells but leaves normal differentiated cells unaffected. After partial unfolding and binding to oleic acid, alpha-lactalbumin forms the HAMLET complex, which enters tumor cells and freezes their metabolic machinery. The cells proceed to fragment their DNA, and they disintegrate with apoptosis-like characteristics. HAMLET kills a wide range of malignant cells in vitro and maintains this activity in vivo in patients with skin papillomas. In addition, HAMLET has striking effects on human glioblastomas in a rat xenograft model. After convection-enhanced delivery, HAMLET diffuses throughout the brain, selectively killing tumor cells and controlling tumor progression without apparent tissue toxicity. HAMLET thus shows great promise as a new therapeutic with the advantage of selectivity for tumor cells and lack of toxicity.

  13. How to target apoptosis signaling pathways for the treatment of pediatric cancers

    Directory of Open Access Journals (Sweden)

    Simone eFulda

    2013-02-01

    Full Text Available Apoptosis represents one of the most important forms of cell death in higher organisms and is typically dysregulated in human cancers, including pediatric tumors. This implies that ineffective engagement of cell death programs can contribute to tumor formation as well as tumor progression. In addition, the majority of cytotoxic therapeutic principles rely on the activation of cell death signaling pathways in cancer cells. Blockade of signaling networks that lead to cell death can therefore confer treatment resistance. A variety of genetic and epigenetic events as well as dysfunctional regulation of signaling networks have been identified as underlying causes of cell death resistance in childhood malignancies. Apoptosis pathways can be therapeutically exploited by enhancing proapoptotic signals or by neutralizing antiapoptotic programs. The challenge in the coming years will be to successfully transfer this knowledge into the development of innovative treatment approaches for children with cancer.

  14. Activation of the UPR protects against cigarette smoke-induced RPE apoptosis through up-regulation of Nrf2.

    Science.gov (United States)

    Huang, Chuangxin; Wang, Joshua J; Ma, Jacey H; Jin, Chenjin; Yu, Qiang; Zhang, Sarah X

    2015-02-27

    Recent studies have revealed a role of endoplasmic reticulum (ER) stress-induced unfolded protein response (UPR) in the regulation of RPE cell activity and survival. Herein, we examined the mechanisms by which the UPR modulates apoptotic signaling in human RPE cells challenged with cigarette smoking extract (CSE). Our results show that CSE exposure induced a dose- and time-dependent increase in ER stress markers, enhanced reactive oxygen species (ROS), mitochondrial fragmentation, and apoptosis of RPE cells. These changes were prevented by the anti-oxidant NAC or chemical chaperone TMAO, suggesting a close interaction between oxidative and ER stress in CSE-induced apoptosis. To decipher the role of the UPR, overexpression or down-regulation of XBP1 and CHOP genes was manipulated by adenovirus or siRNA. Overexpressing XBP1 protected against CSE-induced apoptosis by reducing CHOP, p-p38, and caspase-3 activation. In contrast, XBP1 knockdown sensitized the cells to CSE-induced apoptosis, which is likely through a CHOP-independent pathway. Surprisingly, knockdown of CHOP reduced p-eIF2α and Nrf2 resulting in a marked increase in caspase-3 activation and apoptosis. Furthermore, Nrf2 inhibition increased ER stress and exacerbated cell apoptosis, while Nrf2 overexpression reduced CHOP and protected RPE cells. Our data suggest that although CHOP may function as a pro-apoptotic gene during ER stress, it is also required for Nrf2 up-regulation and RPE cell survival. In addition, enhancing Nrf2 and XBP1 activity may help reduce oxidative and ER stress and protect RPE cells from cigarette smoke-induced damage. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  15. Artesunate induces AIF-dependent apoptosis in A549 cells

    Science.gov (United States)

    Zhou, Chen-juan; Chen, Tong-Sheng

    2012-03-01

    Artesunate (ART), a semi-synthetic derivative of the sesquiterpene artemisinin extracted from the Chinese herb Artemisia annua, exerts a broad spectrum of clinical activity against human cancers. It has been shown that ART induces cancer cells death through apoptosis pathway. This study investigated whether ART treatment induced reactive oxygen species (ROS)-dependent cell death in the apoptosis fashion in human lung adenocarconoma A549 cell line and the proapoptotic protein apoptosis inducing factor (AIF) is involved in ART-induced apoptosis. Cells treated with ART exhibited typical apoptotic morphology as chromatin condensation, margination and shrunken nucleus. ART treatment also induced a loss of mitochondrial membrane potential and AIF release from mitochondria. Silencing AIF can remarkable attenuated ART-induced apoptosis. Collectively, ART induces apoptosis by caspase-independent intrinsic pathway in A549 cells.

  16. Maternal diabetes modulates offspring cell proliferation and apoptosis during odontogenesis via the TLR4/NF-κB signalling pathway.

    Science.gov (United States)

    Chen, Guoqing; Sun, Wenhua; Liang, Yan; Chen, Tian; Guo, Weihua; Tian, Weidong

    2017-06-01

    Maternal gestational diabetes leads to an adverse in utero environment and increases the risk of malformations during embryo organogenesis. In the present study, we analysed the effects of maternal diabetes on tooth germ cell proliferation and apoptosis in offspring, and investigated their underlying mechanisms. A rat model of maternal diabetes was induced by intraperitoneal injection of streptozotocin and the pregnant rats were divided into three groups: controls, the diabetic group and diabetic group with insulin treatment. Offspring of the three groups were collected and cell proliferation and apoptosis in tooth germs were analysed. Primary dental papilla cells and dental epithelial stem cells were isolated and treated with high glucose in vitro, in an attempt to simulate maternal diabetes-induced hyperglycaemia in vivo. Maternal diabetes significantly affected cell proliferation and apoptosis in offspring tooth germs. The TLR4/NF-ĸB signalling pathway was activated in the tooth germs of offspring of diabetic dams. High glucose treatment activated the TLR4/NF-ĸB signalling pathway in primary dental papilla cells and dental epithelial stem cells in vitro, resulting in suppression of cell proliferation and enhancement of apoptosis. TLR4 knockdown significantly reduced adverse effects induced by high glucose treatment. Maternal gestational diabetes significantly impaired dental epithelial and mesenchymal cell proliferation and apoptosis in offspring, possibly by activation of the TLR4/NF-ĸB signalling pathway. © 2016 John Wiley & Sons Ltd.

  17. Indomethacin promotes apoptosis in gastric cancer cells through concomitant degradation of Survivin and Aurora B kinase proteins.

    Science.gov (United States)

    Chiou, Shiun-Kwei; Hoa, Neil; Hodges, Amy; Ge, Lishen; Jadus, Martin R

    2014-09-01

    Regular usage of nonsteroidal anti-inflammatory drugs (NSAIDs) is associated with reduced incidence of a variety of cancers. The molecular mechanisms underlying these chemopreventive effects remain poorly understood. This current investigation showed that in gastric cancer cells: (1) Indomethacin treatment enhanced the degradation of chromosomal passenger proteins, Survivin and Aurora B kinase; (2) Indomethacin treatment down-regulated Aurora B kinase activity in a cell cycle-independent fashion; (3) siRNA knockdown of Survivin level promoted Aurora B kinase protein degradation, and vice versa; (4) ectopic overexpression of Survivin blocked reduction of Aurora B kinase level and activity by indomethacin treatment, and vice versa; (5) siRNA knockdown of Aurora B kinase level and AZD1152 inhibition of its activity induced apoptosis, and overexpression of Aurora B kinase inhibited indomethacin-induced apoptosis; (6) indomethacin treatment reduced Aurora B kinase level, coinciding with reduction of Survivin level and induction of apoptosis, in KATO III and HT-29 cells, and in mouse gastric mucosa. A role for Aurora B kinase function in NSAID-induced apoptosis was not previously explored. Thus this report provides better understanding of the molecular mechanisms underlying the anti-cancer effect of NSAIDs by elucidating a significant role for Aurora B kinase in indomethacin-induced apoptosis.

  18. Mesenchymal Stem Cells Protect Nucleus Pulposus Cells from Compression-Induced Apoptosis by Inhibiting the Mitochondrial Pathway

    Directory of Open Access Journals (Sweden)

    Sheng Chen

    2017-01-01

    Full Text Available Objective. Excessive apoptosis of nucleus pulposus cells (NPCs induced by various stresses, including compression, contributes to the development of intervertebral disc degeneration (IVDD. Mesenchymal stem cells (MSCs can benefit the regeneration of NPCs and delay IVDD, but the underlying molecular mechanism is poorly understood. This study aimed to evaluate the antiapoptosis effects of bone marrow-derived MSC (BMSC on rat NPCs exposed to compression and investigate whether the mitochondrial pathway was involved. Methods. BMSCs and NPCs were cocultured in the compression apparatus at 1.0 MPa for 36 h. Cell viability, apoptosis, mitochondrial function, and the expression of apoptosis-related proteins were evaluated. Results. The results showed that coculturing with BMSCs increased the cell viability and reduced apoptosis of NPCs exposed to compression. Meanwhile, BMSCs could relieve the compression-induced mitochondrial damage of NPCs by decreasing reactive oxygen species level and maintaining mitochondrial membrane potential as well as mitochondrial integrity. Furthermore, coculturing with BMSCs suppressed the activated caspase-3 and activated caspase-9, decreased the expressions of cytosolic cytochrome c and Bax, and increased the expression of Bcl-2. Conclusions. Our results suggest that BMSCs can protect against compression-induced apoptosis of NPCs by inhibiting the mitochondrial pathway and thus enhance our understanding on the MSC-based therapy for IVDD.

  19. Metabolomics profiles delineate uridine deficiency contributes to mitochondria-mediated apoptosis induced by celastrol in human acute promyelocytic leukemia cells.

    Science.gov (United States)

    Zhang, Xiaoling; Yang, Jing; Chen, Minjian; Li, Lei; Huan, Fei; Li, Aiping; Liu, Yanqing; Xia, Yankai; Duan, Jin-Ao; Ma, Shiping

    2016-07-19

    Celastrol, extracted from "Thunder of God Vine", is a promising anti-cancer natural product. However, its effect on acute promyelocytic leukemia (APL) and underlying molecular mechanism are poorly understood. The purpose of this study was to explore its effect on APL and underlying mechanism based on metabolomics. Firstly, multiple assays indicated that celastrol could induce apoptosis of APL cells via p53-activated mitochondrial pathway. Secondly, unbiased metabolomics revealed that uridine was the most notable changed metabolite. Further study verified that uridine could reverse the apoptosis induced by celastrol. The decreased uridine was caused by suppressing the expression of gene encoding Dihydroorotate dehydrogenase, whose inhibitor could also induce apoptosis of APL cells. At last, mouse model confirmed that celastrol inhibited tumor growth through enhanced apoptosis. Celastrol could also decrease uridine and DHODH protein level in tumor tissues. Our in vivo study also indicated that celastrol had no systemic toxicity at pharmacological dose (2 mg/kg, i.p., 21 days). Altogether, our metabolomics study firstly reveals that uridine deficiency contributes to mitochondrial apoptosis induced by celastrol in APL cells. Celastrol shows great potential for the treatment of APL.

  20. Targeting Death Receptor TRAIL-R2 by Chalcones for TRAIL-Induced Apoptosis in Cancer Cells

    Science.gov (United States)

    Szliszka, Ewelina; Jaworska, Dagmara; Kłósek, Małgorzata; Czuba, Zenon P.; Król, Wojciech

    2012-01-01

    Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) induces apoptosis in cancer cells without toxicity to normal cells. TRAIL binds to death receptors, TRAIL-R1 (DR4) and TRAIL-R2 (DR5) expressed on cancer cell surface and activates apoptotic pathways. Endogenous TRAIL plays an important role in immune surveillance and defense against cancer cells. However, as more tumor cells are reported to be resistant to TRAIL mediated death, it is important to search for and develop new strategies to overcome this resistance. Chalcones can sensitize cancer cells to TRAIL-induced apoptosis. We examined the cytotoxic and apoptotic effects of TRAIL in combination with four chalcones: chalcone, isobavachalcone, licochalcone A and xanthohumol on HeLa cancer cells. The cytotoxicity was measured by MTT and LDH assays. The apoptosis was detected using annexin V-FITC staining by flow cytometry and fluorescence microscopy. Death receptor expression was analyzed using flow cytometry. The decreased expression of death receptors in cancer cells may be the cause of TRAIL-resistance. Chalcones enhance TRAIL-induced apoptosis in HeLa cells through increased expression of TRAIL-R2. Our study has indicated that chalcones augment the antitumor activity of TRAIL and confirm their cancer chemopreventive properties. PMID:23203129

  1. Porphyromonas gingivalis modulates Pseudomonas aeruginosa-induced apoptosis of respiratory epithelial cells through the STAT3 signaling pathway.

    Science.gov (United States)

    Li, Qian; Pan, Chunling; Teng, Di; Lin, Li; Kou, Yurong; Haase, Elaine M; Scannapieco, Frank A; Pan, Yaping

    2014-01-01

    Pseudomonas aeruginosa is an important opportunistic bacterial pathogen, causing infections of respiratory and other organ systems in immunocompromised hosts that may invade and proliferate in mucosal epithelial cells to induce apoptosis. Previous studies suggest that oral bacteria, especially gram-negative periodontal pathogens, may enhance P. aeruginosa invasion into respiratory epithelial cells to augment tissue destruction. In this study, we investigated the effect of the periodontopathogen Porphyromonas gingivalis on P. aeruginosa-induced epithelial cell apoptosis. P. gingivalis invasion transiently inhibited P. aeruginosa-induced apoptosis in respiratory epithelial cells via the signal transducer and activator of transcription 3 (STAT3) signaling pathway. The activated STAT3 up-regulated the downstream anti-apoptotic moleculars survivin and B-cell leukemia-2 (bcl-2). This process was accompanied by down-regulation of pro-apoptosis molecular Bcl-2-associated death promoter (bad) and caspase-3 activity inhibition. In addition, the activation of the STAT3 pathway was affected by P. gingivalis in a dose-dependent manner. Finally, co-invasion of P. aeruginosa and P. gingivalis led to greater cell death compared with P. aeruginosa challenge alone. These results suggest that regulation of P. aeruginosa-induced apoptosis by P. gingivalis contributes to the pathogenesis of respiratory disease. Interference with this process may provide a potential therapeutic strategy for the treatment and prevention of respiratory disease. Copyright © 2013 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

  2. Trimetazidine Protects Umbilical Cord Mesenchymal Stem Cells Against Hypoxia and Serum Deprivation Induced Apoptosis by Activation of Akt

    Directory of Open Access Journals (Sweden)

    Xuhe Gong

    2014-12-01

    Full Text Available Background: Mesenchymal stem cell (MSC transplantation is a promising therapy for cardiac repair. However, the efficacy is limited by the poor viability of MSCs in the infarcted heart. Recent findings have implicated that trimetazidine (TMZ enhanced the survival of the stem cells under various conditions. However, as the stem cells in these studies were animal-derived, little information is available about the effects of TMZ on human MSCs. Herein, we propose that TMZ may protect human MSCs against apoptosis induced by Hypoxia/Serum deprivation (H/SD. Methods: Human umbilical cord MSCs (UC-MSCs from Wharton's jelly were pretreated with 10µM TMZ of H/SD with or without the Akt inhibitor LY294002. The morphological changes were assessed using Hoechst 33342. Apoptosis was evaluated via Annexin V/PI staining; and apoptosis-related proteins were detected using Western-blot. Protein chip technology was used to screen for differences between the cell supernatants. Results: TMZ had a significant protective effect against H/SD-induced apoptosis, accompanied by an increase in Bcl-2 and p-Akt. The TMZ-mediated anti-apoptotic effect on MSCs could be attenuated by treatment with LY294002. Moreover, protein chip assays showed that TMZ treatment increased the paracrine functions of MSCs. Conclusion: Trimetazidine protects human UC-MSCs from H/SD-induced apoptosis via the Akt pathway and may therefore be a potentially useful therapeutic adjunct for transplanting MSCs into damaged heart after myocardial infarction.

  3. Protective role of morin, a flavonoid, against high glucose induced oxidative stress mediated apoptosis in primary rat hepatocytes.

    Directory of Open Access Journals (Sweden)

    Radhika Kapoor

    Full Text Available Apoptosis is an early event of liver damage in diabetes and oxidative stress has been linked to accelerate the apoptosis in hepatocytes. Therefore, the compounds that can scavenge ROS may confer regulatory effects on high-glucose induced apoptosis. In the present study, primary rat hepatocytes were exposed to high concentration (40 mM of glucose. At this concentration decreased cell viability and enhanced ROS generation was observed. Depleted antioxidant status of hepatocytes under high glucose stress was also observed as evident from transcriptional level and activities of antioxidant enzymes. Further, mitochondrial depolarisation was accompanied by the loss of mitochondrial integrity and altered expression of Bax and Bcl-2. Increased translocation of apoptotic proteins like AIF (Apoptosis inducing factor & Endo-G (endonuclease-G from its resident place mitochondria to nucleus was also observed. Cyt-c residing in the inter-membrane space of mitochondria also translocated to cytoplasm. These apoptotic proteins initiated caspase activation, DNA fragmentation, chromatin condensation, increased apoptotic DNA content in glucose treated hepatocytes, suggesting mitochondria mediated apoptotic mode of cell death. Morin, a dietary flavonoid from Psidium guajava was effective in increasing the cell viability and decreasing the ROS level. It maintained mitochondrial integrity, inhibited release of apoptotic proteins from mitochondria, prevented DNA fragmentation, chromatin condensation and hypodiploid DNA upon exposure to high glucose. This study confirms the capacity of dietary flavonoid Morin in regulating apoptosis induced by high glucose via mitochondrial mediated pathway through intervention of oxidative stress.

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