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Sample records for paraquat-induced cell death

  1. Chloroquine rescues A549 cells from paraquat-induced death.

    PubMed

    Xu, Lingjie; Wang, Zhong

    2016-04-01

    Paraquat (PQ) is a widely used herbicide associated with a high mortality rate, yet, there are no effective treatments for PQ poisoning. PQ may damage alveolar type II cells leading to moderate to severe acute respiratory distress syndrome (ARDS). The present study was undertaken to show that PQ causes alveolar type II (A549) cell death and to evaluate whether chloroquine (CQ) can protect A549 cells against PQ-induced cell death. The results showed that high concentrations of PQ resulted in toxicity, as indicated by a decrease in cell viability. More importantly, for the first time, CQ was found to improve cell viability of PQ treated A549 cells. Moreover, our data demonstrated that CQ increased lysosome-associated membrane protein-1, lysosome-associated membrane protein-2 and light chain-3 expressions, suggesting that the mechanism by which CQ rescues PQ-induced cytotoxicity may be through protection of the lysosomal membrane or up-regulation of autophagy. In conclusion, our study indicates that CQ may be used as a potential drug to rescue PQ-induced ARDS. PMID:26154125

  2. Paraquat Induces Cell Death Through Impairing Mitochondrial Membrane Permeability.

    PubMed

    Huang, Chuen-Lin; Chao, Chih-Chang; Lee, Yi-Chao; Lu, Mei-Kuang; Cheng, Jing-Jy; Yang, Ying-Chen; Wang, Vin-Chi; Chang, Wen-Chang; Huang, Nai-Kuei

    2016-05-01

    Paraquat (PQ) as a Parkinsonian mimetic has been demonstrated to impair dopaminergic (DAergic) neurons and is highly correlated with the etiology of Parkinson's disease (PD) where the death of DAergic neurons has been mainly attributed to impaired mitochondrial functioning. In this study, PQ-induced cytotoxicity focusing on mitochondrial membrane permeability (MMP), which has been implicated to play a part in neurodegeneration, was investigated. Primarily, PQ-induced cytotoxicity and reactive oxygen species (ROS) were inhibited by an inhibitor of NADPH oxidase (NOX), indicating the toxic effect of PQ redox cycling. Further, dibucaine and cyclosporin A which respectively inhibit mitochondrial apoptosis-induced channels (MAC) and mitochondrial permeability transition pores (mPTP) were used and found to prevent PQ-induced mitochondrial dysfunction, such as decreased mitochondrial membrane potential and increased MMP, mitochondrial ROS, and pro-apoptotic factor release. Knockdown of bax and/or bak blocked PQ-induced mitochondrial clusterization of Bax and/or Bak and cytotoxicity, demonstrating the significance of MAC which is composed of Bax and/or Bak. This clusterization coincided with the release of mitochondrial apoptotic factors before there was an increase in inner MMP, indicating that MAC may precede mPTP formation. Besides, NOX inhibitor but not dibucaine attenuated the earlier PQ-induced cytosolic ROS formation or Bax and/or Bak clusterization indicating PQ redox cycling may account for MAC formation. In this model, we have resolved for the first that PQ cytotoxicity through redox cycling may sequentially result in increased outer (MAC) and inner (mPTP) MMP and suggested MMP could be implicated as a therapeutic target in treating neurodegenerative diseases like PD. PMID:25947082

  3. Minocycline prevents paraquat-induced cell death through attenuating endoplasmic reticulum stress and mitochondrial dysfunction.

    PubMed

    Huang, Chuen-Lin; Lee, Yi-Chao; Yang, Ying-Chen; Kuo, Tsun-Yung; Huang, Nai-Kuei

    2012-03-25

    Paraquat (PQ) was demonstrated to induce dopaminergic neuron death and is used as a Parkinson's disease (PD) mimetic; however, its mechanism remains contradictory. Alternatively, minocycline is a second-generation tetracycline and is undergoing clinical trials for treating PD with an unresolved mechanism. We thus investigated the molecular mechanism of minocycline in preventing PQ-induced cytotoxicity. In this study, minocycline was effective in preventing PQ-induced apoptotic cell death, which involves the cleavages of poly (ADP-ribose) polymerase (PARP) and caspase 3 and increased fluorescence intensity of annexin V-FITC. In addition, PQ also quickly induced alterations of unfolded protein responses (UPRs) and subsequently dysfunction of the mitochondria (such as the decrease in membrane potential and increase in membrane permeability and superoxide formation). Finally, the mechanism of minocycline in preventing PQ-induced apoptosis might be mediated by attenuating endoplasmic reticulum (ER) stress and mitochondrial dysfunction, which respectively results in caspase-12 activation and the release of H2O2, HtrA2/Omi, and Smac/Diablo. Thus, minocycline could possibly be used to treat other neurodegenerative disorders with similar pathologic mechanisms. PMID:22245251

  4. Melatonin inhibits paraquat-induced cell death in bovine preimplantation embryos.

    PubMed

    Pang, Yun-Wei; Sun, Ye-Qing; Sun, Wei-Jun; Du, Wei-Hua; Hao, Hai-Sheng; Zhao, Shan-Jiang; Zhu, Hua-Bin

    2016-03-01

    Preimplantation embryos are sensitive to oxidative stress-induced damage that can be caused by reactive oxygen species (ROS) originating from normal embryonic metabolism and/or the external surroundings. Paraquat (PQ), a commonly used pesticide and potent ROS generator, can induce embryotoxicity. The present study aimed to investigate the effects of melatonin on PQ-induced damage during embryonic development in bovine preimplantation embryos. PQ treatment significantly reduced the ability of bovine embryos to develop to the blastocyst stage, and the addition of melatonin markedly reversed the developmental failure caused by PQ (20.9% versus 14.3%). Apoptotic assay showed that melatonin pretreatment did not change the total cell number in blastocysts, but the incidence of apoptotic nuclei and the release of cytochrome c were significantly decreased. Using real-time quantitative polymerase chain reaction analysis, we found that melatonin pre-incubation significantly altered the expression levels of genes associated with redox signaling, particularly by attenuating the transcript level of Txnip and reinforcing the expression of Trx. Furthermore, melatonin pretreatment significantly reduced the expression of the pro-apoptotic caspase-3 and Bax, while the expression of the anti-apoptotic Bcl-2 and XIAP was unaffected. Western blot analysis showed that melatonin protected bovine embryos from PQ-induced damage in a p38-dependent manner, but extracellular signal-regulated kinase (ERK) and c-JUN N-terminal kinase (JNK) did not appear to be involved. Together, these results identify an underlying mechanism by which melatonin enhances the developmental potential of bovine preimplantation embryos under oxidative stress conditions. PMID:26607207

  5. WldS Reduces Paraquat-Induced Cytotoxicity via SIRT1 in Non-Neuronal Cells by Attenuating the Depletion of NAD

    PubMed Central

    Yu, Qiujing; Wang, Ting; Zhou, Xuexia; Wu, Jingxia; Chen, Xingmiao; Liu, Yang; Wu, Dongmei; Zhai, Qiwei

    2011-01-01

    WldS is a fusion protein with NAD synthesis activity, and has been reported to protect axonal and synaptic compartments of neurons from various mechanical, genetic and chemical insults. However, whether WldS can protect non-neuronal cells against toxic chemicals is largely unknown. Here we found that WldS significantly reduced the cytotoxicity of bipyridylium herbicides paraquat and diquat in mouse embryonic fibroblasts, but had no effect on the cytotoxicity induced by chromium (VI), hydrogen peroxide, etoposide, tunicamycin or brefeldin A. WldS also slowed down the death of mice induced by intraperitoneal injection of paraquat. Further studies demonstrated that WldS markedly attenuated mitochondrial injury including disruption of mitochondrial membrane potential, structural damage and decline of ATP induced by paraquat. Disruption of the NAD synthesis activity of WldS by an H112A or F116S point mutation resulted in loss of its protective function against paraquat-induced cell death. Furthermore, WldS delayed the decrease of intracellular NAD levels induced by paraquat. Similarly, treatment with NAD or its precursor nicotinamide mononucleotide attenuated paraquat-induced cytotoxicity and decline of ATP and NAD levels. In addition, we showed that SIRT1 was required for both exogenous NAD and WldS-mediated cellular protection against paraquat. These findings suggest that NAD and SIRT1 mediate the protective function of WldS against the cytotoxicity induced by paraquat, which provides new clues for the mechanisms underlying the protective function of WldS in both neuronal and non-neuronal cells, and implies that attenuation of NAD depletion may be effective to alleviate paraquat poisoning. PMID:21750730

  6. Low-Dose Aronia melanocarpa Concentrate Attenuates Paraquat-Induced Neurotoxicity.

    PubMed

    Case, A J; Agraz, D; Ahmad, I M; Zimmerman, M C

    2016-01-01

    Herbicides containing paraquat may contribute to the pathogenesis of neurodegenerative disorders such as Parkinson's disease. Paraquat induces reactive oxygen species-mediated apoptosis in neurons, which is a primary mechanism behind its toxicity. We sought to test the effectiveness of a commercially available polyphenol-rich Aronia melanocarpa (aronia berry) concentrate in the amelioration of paraquat-induced neurotoxicity. Considering the abundance of antioxidants in aronia berries, we hypothesized that aronia berry concentrate attenuates the paraquat-induced increase in reactive oxygen species and protects against paraquat-mediated neuronal cell death. Using a neuronal cell culture model, we observed that low doses of aronia berry concentrate protected against paraquat-mediated neurotoxicity. Additionally, low doses of the concentrate attenuated the paraquat-induced increase in superoxide, hydrogen peroxide, and oxidized glutathione levels. Interestingly, high doses of aronia berry concentrate increased neuronal superoxide levels independent of paraquat, while at the same time decreasing hydrogen peroxide. Moreover, high-dose aronia berry concentrate potentiated paraquat-induced superoxide production and neuronal cell death. In summary, aronia berry concentrate at low doses restores the homeostatic redox environment of neurons treated with paraquat, while high doses exacerbate the imbalance leading to further cell death. Our findings support that moderate levels of aronia berry concentrate may prevent reactive oxygen species-mediated neurotoxicity. PMID:26770655

  7. Low-Dose Aronia melanocarpa Concentrate Attenuates Paraquat-Induced Neurotoxicity

    PubMed Central

    Case, A. J.; Agraz, D.; Ahmad, I. M.; Zimmerman, M. C.

    2016-01-01

    Herbicides containing paraquat may contribute to the pathogenesis of neurodegenerative disorders such as Parkinson's disease. Paraquat induces reactive oxygen species-mediated apoptosis in neurons, which is a primary mechanism behind its toxicity. We sought to test the effectiveness of a commercially available polyphenol-rich Aronia melanocarpa (aronia berry) concentrate in the amelioration of paraquat-induced neurotoxicity. Considering the abundance of antioxidants in aronia berries, we hypothesized that aronia berry concentrate attenuates the paraquat-induced increase in reactive oxygen species and protects against paraquat-mediated neuronal cell death. Using a neuronal cell culture model, we observed that low doses of aronia berry concentrate protected against paraquat-mediated neurotoxicity. Additionally, low doses of the concentrate attenuated the paraquat-induced increase in superoxide, hydrogen peroxide, and oxidized glutathione levels. Interestingly, high doses of aronia berry concentrate increased neuronal superoxide levels independent of paraquat, while at the same time decreasing hydrogen peroxide. Moreover, high-dose aronia berry concentrate potentiated paraquat-induced superoxide production and neuronal cell death. In summary, aronia berry concentrate at low doses restores the homeostatic redox environment of neurons treated with paraquat, while high doses exacerbate the imbalance leading to further cell death. Our findings support that moderate levels of aronia berry concentrate may prevent reactive oxygen species-mediated neurotoxicity. PMID:26770655

  8. Prochelator BHAPI Protects Cells against Paraquat-Induced Damage by ROS-Triggered Iron Chelation

    PubMed Central

    Kielar, Filip; Helsel, Marian E.; Wang, Qin

    2012-01-01

    A prochelator named BHAPI (N′-(1-(2-(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)benzyloxy)phenyl)ethylidene)isonitotinohdrazide) based on the structure of experimental metal chelator HAPI (N′-[1-(2-hydroxyphenyl)ethyliden]isonicotinoylhydrazide) has been synthesized. The prochelator, which shows limited affinity for metal ions, is converted efficiently upon reaction with hydrogen peroxide into its chelator form, which binds di- and trivalent metal ions, including Zn2+, Cu2+ and Fe3+. This work shows that the prochelator has a protective effect on cells under oxidative stress induced by either hydrogen peroxide or the cytotoxic herbicide paraquat. The effect of BHAPI and HAPI on cellular iron status was assessed by monitoring the mRNA level of the transferrin receptor. Whereas the chelator HAPI induces iron deficiency in cultured retinal pigment epithelial cells, the prochelator does not, providing evidence that the differential metal-binding capacity of these compounds observed in vitro is replicated in the cellular context. PMID:22700084

  9. CURCUMIN ENHANCES PARAQUAT-INDUCED APOPTOSIS OF N27 MESENCEPHALIC CELLS VIA THE GENERATION OF REACTIVE OXYGEN SPECIES

    PubMed Central

    Ortiz-Ortiz, Miguel A.; Morán, José M.; Bravosanpedro, Jose M.; González-Polo, Rosa A.; Niso-Santano, Mireia; Anantharam, Vellareddy; Kanthasamy, Anumantha G.; Soler, Germán; Fuentes, José M.

    2009-01-01

    Curcumin, the active compound of the rhizome of Curcuma longa has anti-inflammatory, antioxidant and antiproliferative activities. This agent has been shown to regulate numerous transcription factors, cytokines, protein kinases, adhesion molecules, redox status and enzymes that have been linked to inflammation. While curcumin has been identified as an activator of apopotosis in several cell lines, the mechanism by which it initiates apoptosis, however, remains poorly understood. We considered curcumin from the point of view of its ability to protect against oxidative stress, the latter being one factor strongly implicated in the development of Parkinson’s disease. Althougth the etiology of Parkinson’s disease remains unknown, epidemiological studies have linked exposure to pesticides such paraquat to an increased risk of developing the condition. Analysis of the neurotoxic properties of these pesticide compounds has been focused on their ability to induce oxidative stress in neural cells. Given curcumin’s capacity to protect against oxidative stress, it has been considered as a potential therapeutic agent for neurodegenerative diseases such as Parkinson’s disease that involve an oxidative stress component. In the present report we describe the effect of curcumin in paraquat-mediated apoptosis of N27 mesencepahlic cells. We show that subtoxic concentrations of curcumin sensitize N27 mesencephalic cells to paraquat-mediated apoptosis. PMID:19660496

  10. Persistence and prevention of aluminium- and paraquat-induced adaptive response to methyl mercuric chloride in plant cells in vivo.

    PubMed

    Patra, Jita; Sahoo, Malaya K; Panda, Brahma B

    2003-07-01

    Induction and persistence of adaptive response by aluminium (Al), 1 or 10 microM, and paraquat (PQ), 5 or 10 microM, against genotoxicity of methyl mercuric chloride (MMCl), 1.26 microM, a standard environmental genotoxin, was investigated in root meristem cells of Allium cepa. Subsequently, three metabolic inhibitors, namely, 3-aminobezamide (3-AB, 10 or 100 microM), an inhibitor of poly(ADP-ribose) polymerase (PARP) implicated in DNA repair and/or apoptosis, cycloheximide (CH, 0.1 or 1 microM), an inhibitor of protein synthesis, and buthionine sulfoximine (BSO, 100 microM or 1mM), an inhibitor of glutathione synthesis were tested for their ability to prevent the adaptive response induced by conditioning doses of Al, 10 or 100 microM; and PQ, 5 or 100 microM, against MMCl-challenge, 1.26 or 100 microM, in root meristems of A. cepa or embryonic shoots of Hordeum vulgare, respectively. The findings demonstrated that once triggered, the Al- or PQ-adaptive response to MMCl could persist for at least 48h in root meristems of A. cepa. Furthermore, the adaptive response could effectively be prevented by 3-AB, to a lesser degree by CH, and the least by BSO, suggesting primarily the involvement of PARP and implicating DNA repair in the underlying mechanisms of adaptive response in plant cells in vivo. PMID:12834754

  11. The relationship between platelet endothelial cell adhesion molecule-1 and paraquat-induced lung injury in rabbits

    PubMed Central

    Shi, Jing; Hu, Chun-lin; Gao, Yu-feng; Liao, Xiao-xing; Xu, Hope

    2012-01-01

    BACKGROUND: Platelet endothelial cell adhesion molecule-1 (PECAM-1), also known as CD31, is mainly distributed in vascular endothelial cells. Studies have shown that PECAM-1 is a very significant indicator of angiogenesis, and has been used as an indicator for vascular endothelial cells. The present study aimed to explore the relationship between the expression of PECAM-1 and the degree of acute lung injury (ALI) and fibrosis in paraquat (PQ) induced lung injury in rabbits. METHODS: Thirty-six adult New Zealand rabbits were randomly divided into three groups (12 rabbits in each group) according to PQ dosage: 8 mg/kg (group A), 16 mg/kg (group B), and 32 mg/kg (group C). After PQ infusion, the rabbits were monitored for 7 days and then euthanized. The lungs were removed for histological evaluation. Masson staining was used to determine the degree of lung fibrosis (LF), and semi-quantitative immune-histochemistry analysis to determine the expression of PECAM-1. Pearson’s product-moment correlation analysis was performed to evaluate the relationship between the expression of PECAM-1 and the extent of lung injuries expressed by ALI score and degree of LF. RESULTS: Rabbits in the three groups showed apparent poisoning. The rabbits survived longer in group A than in groups B and C (6.47±0.99 days vs. 6.09±1.04 days vs. 4.77±2.04 days) (P<0.05). ALI score was lower in group A than in groups B and C (8.33±1.03 vs. 9.83±1.17 vs. 11.50±1.38) (P<0.05), and there was statistically significant difference between group B and group C (P=0.03). LF was slighter in group A than in groups B and C (31.09%±2.05 % vs. 34.37%±1.62 % vs. 36.54%±0.44%) (P<0.05), and there was statistically significant difference between group B and group C (P=0.026). The PEACAM-1 expression was higher in group A than in groups B and C (20.31%±0.70% vs. 19.34%±0.68% vs. 18.37%±0.46%) (P<0.05), and there was statistically significant difference between group B and group C (P=0.017). Pearson

  12. Unfractionated bone marrow cells attenuate paraquat-induced glomerular injury and acute renal failure by modulating the inflammatory response

    PubMed Central

    Gu, Sing-Yi; Yeh, Ti-Yen; Lin, Shih-Yi; Peng, Fu-Chuo

    2016-01-01

    The aim of this study was to evaluate the efficacy of unfractionated bone marrow cells (BMCs) in attenuating acute kidney injury (AKI) induced by paraquat (PQ) in a mouse model. PQ (55 mg/kg BW) was intraperitoneally injected into C57BL/6 female mice to induce AKI, including renal function failure, glomerular damage and renal tubule injury. Glomerular podocytes were the first target damaged by PQ, which led to glomerular injury. Upon immunofluorescence staining, podocytes depletion was validated and accompanied by increased urinary podocin levels, measured on days 1 and 6. A total of 5.4 × 106 BMCs obtained from the same strain of male mice were injected into AKI mice through the tail vein at 3, 24, and 48 hours after PQ administration. As a result, renal function increased, tubular and glomerular injury were ameliorated, podocytes loss improved, and recipient mortality decreased. In addition, BMCs co-treatment decreased the extent of neutrophil infiltration and modulated the inflammatory response by shifting from pro-inflammatory Th1 to an anti-inflammatory Th2 profile, where IL-1β, TNF-α, IL-6 and IFN-γ levels declined and IL-10 and IL-4 levels increased. The present study provides a platform to investigate PQ-induced AKI and repeated BMCs injection represents an efficient therapeutic strategy. PMID:26988026

  13. Combined treatment with bone marrow mesenchymal stem cells and methylprednisolone in paraquat-induced acute lung injury

    PubMed Central

    2013-01-01

    Background To evaluate the efficacy of combined treatment with bone marrow mesenchymal stem cell (BMSC) transplantation and methylprednisolone (MP) to treat paraquat (PQ)-induced acute lung injury. Materials and methods A total of 102 female rats were randomly divided into five groups: PQ, BMSC, MP, BMSC + MP and normal control. After 14 days of PQ poisoning, the survival of rats, wet/dry weight ratio of lung tissue, serum levels of tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6, IL-10, malondialdehyde (MDA) and superoxidase dismutase (SOD), and the expression of nuclear factor (NF)-кB p65 in lung tissue were determined. Results Rats in BMSC and BMSC + MP groups survived. BMSC transplantation significantly decreased the wet/dry weight ratio of lung tissue, down-regulated NF-кB p65 expression in lung tissue, lowered serum levels of TNF-α, IL-1β, IL-6 and MDA, and increased serum levels of IL-10 and SOD. These changes were particularly significant on days 7–14 after PQ poisoning. The above changes were more significant in the MP group on days 1–3 after PQ poisoning, compared with those of the BMSC group. However, the BMSC + MP group showed more significant changes on days 1–14 after PQ poisoning than those of both BMSC and MP groups. Conclusions MP inhibits the inflammatory response, reduces the products of lipid peroxidation and promotes survival of transplanted BMSC, thus improving the intermediate and longer term efficacy of BMSC transplantation for treatment of PQ-induced lung injury. PMID:23902576

  14. Protective effects of melatonin-loaded lipid-core nanocapsules on paraquat-induced cytotoxicity and genotoxicity in a pulmonary cell line.

    PubMed

    Charão, Mariele F; Baierle, Marília; Gauer, Bruna; Goethel, Gabriela; Fracasso, Rafael; Paese, Karina; Brucker, Natália; Moro, Angela M; Bubols, Guilherme B; Dias, Bruna B; Matte, Ursula S; Guterres, Silvia S; Pohlmann, Adriana R; Garcia, Solange C

    2015-06-01

    Many acute poisonings lack effective and specific antidotes. Due to both intentional and accidental exposures, paraquat (PQ) causes thousands of deaths annually, especially by pulmonary fibrosis. Melatonin (Mel), when incorporated into lipid-core nanocapsules (Mel-LNC), has enhanced antioxidant properties. The effects of such a formulation have not yet been studied with respect to mitigation of PQ- induced cytotoxicity and DNA damage. Here, we have tested whether Mel-LNC can ameliorate PQ-induced toxicity in the A549 alveolar epithelial cell line. Physicochemical characterization of the formulations was performed. Cellular uptake was measured using nanocapsules marked with rhodamine B. Cell viability was determined by the MTT assay and DNA damage was assessed by the comet assay. The enzyme-modified comet assay with endonuclease III (Endo III) and formamidopyrimidine glycosylase (FPG) were used to investigate oxidative DNA damage. Incubation with culture medium for 24h did not alter the granulometric profile of Mel-LNC formulations. Following treatment (3 and 24h), red fluorescence was detected around the cell nucleus, indicating internalization of the formulation. Melatonin solution (Mel), Mel-LNC, and LNC did not have significant effects on cell viability or DNA damage. Pre-treatment with Mel-LNC enhanced cell viability and showed a remarkable reduction in % DNA in tail compared to the PQ group; this was not observed in cells pre-treated with Mel. PQ induces oxidative DNA damage detected with the enzyme-modified comet assay. Mel-LNC reduced this damage more effectively than did Mel. In summary, Mel-LNC is better than Mel at protecting A549 cells from the cytotoxic and genotoxic effects of PQ. PMID:26046970

  15. Pyrrolidine Dithiocarbamate Attenuates Paraquat-Induced Lung Injury in Rats

    PubMed Central

    Chang, Xiuli; Shao, Chunfeng; Wu, Qing; Wu, Qiangen; Huang, Min; Zhou, Zhijun

    2009-01-01

    Paraquat (PQ) has been demonstrated that the main target organ for the toxicity is the lung. This study aimed to investigate the potential protective effect of PDTC on the PQ-induced pulmonary damage. Fifty-four rats were divided into control, PQ-treated and PQ+PDTC-treated groups. Rats in the PQ group were administrated 40 mg/kg PQ by gastric gavage, and PDTC group with 40 mg/kg PQ followed by injection of 120 mg/kg PDTC (IP). On the days 3, 7, 14 and 21 after treatments, the activities of GSH-Px, SOD, MDA level and the content of HYP were measured. TGF-β1 mRNA and protein were assayed by RT-PCR and ELISA. MDA level in plasma and BALF was increased and the activities of GSH-Px and SOD were decreased significantly in the PQ-treated groups (P < .05) compared with control group. While the activities of GSH-Px and SOD in the PQ+PDTC-treated groups was markedly higher than that of PQ-treated groups (P < .05), and in contrast, MDA level was lower. TGF-β1 mRNA and protein were significantly lower in the PQ+PDTC-treated groups than that of PQ-treated groups (P < .05). The histopathological changes in the PQ+PDTC-treated groups were milder than those of PQ groups. Our results suggested that PDTC treatment significantly attenuated paraquat-induced pulmonary damage. PMID:19639047

  16. Histamine action in paraquat-induced lung injury.

    PubMed

    Lindenschmidt, R C; Selig, W M; Patterson, C E; Verburg, K M; Henry, D P; Forney, R B; Rhoades, R A

    1986-02-01

    We investigated direct histamine release and its effects in edema formation following paraquat (PQ) injury in a blood-free, perfused rat lung preparation. Under control conditions, perfusate histamine levels from the lung averaged 9.5 +/- 1.4 ng/ml. Lungs perfused with paraquat (1 mM) showed marked increases in pulmonary arterial pressure (133%), airway pressure (74%), alveolarcapillary protein flux (200%), and lung weight (38%). Prior to any detectable lung weight or pressure changes, PQ caused a 300% increase in perfusate histamine. Diphenhydramine (1.0 X 10(-5) M), a specific H1-histamine receptor antagonist, blocked the increased protein flux that followed PQ administration and significantly delayed edema. Furthermore, diphenhydramine attenuated the rise in PGF2 alpha. Conversely, histamine release was partially attenuated by the cyclooxygenase inhibitor, ibuprofen, at 2.4 X 10(-5) M, the same level that we had previously shown to block an early rise in PGF2 alpha and the onset of edema after PQ. These data show that the increased alveolar-capillary protein flux that occurred with PQ injury was attenuated by an H1-receptor antagonist and suggest that histamine is a primary mediator in paraquat-induced injury and that histamine subsequently stimulates prostaglandin release. PMID:3456218

  17. Programmed cell death

    SciTech Connect

    1995-12-31

    The purpose of this conference to provide a multidisciplinary forum for exchange of state-of-the-art information on the role programmed cell death plays in normal development and homeostasis of many organisms. This volume contains abstracts of papers in the following areas: invertebrate development; immunology/neurology; bcl-2 family; biochemistry; programmed cell death in viruses; oncogenesis; vertebrate development; and diseases.

  18. The Protective Effect of Sodium Ferulate and Oxymatrine Combination on Paraquat-induced Lung Injury

    PubMed Central

    Wang, Wei; Pei, Xiaokun; Xu, Mengxin; Sun, Songmei; Zhang, Chunlei; Mu, Keying; Liu, Zhifeng

    2015-01-01

    Experimental evidence suggested that sodium ferulate (SF) and oxymatrine (OMT) combination had synergistic anti-inflammatory and antioxidant effects. We hypothesized that SF and OMT combination treatment might have protective effects on paraquat-induced acute lung injury. In our study, the Swiss mice were randomly divided into seven groups, including control, paraquat (PQ), SF (6.2 mg/Kg/day); OMT (13.8 mg/Kg/day) and three SF+OMT groups (3.1 + 6.9; 6.2 + 13.8 and 12.3 + 27.7 mg/Kg/day). The mortality and death time were monitored. Sprague-Dawley rats were randomly divided into seven groups including control, PQ, SF (3.1 mg/Kg/day); OMT (6.9 mg/Kg/day) and three SF+OMT groups (1.6 + 3.4; 3.1 + 6.9 and 6.2 + 13.8 mg/Kg/day). The lung wet/dry weight (W/D) ratio, lung histopathologic changes, C-reactive protein (CRP), interleukin-6 (IL-6), nuclear factor κB (NF-κB), malondialdehyde (MDA) and superoxidase dismutase (SOD) were analysed. Compared with PQ group, the mortality significantly decreased and the death time prolonged in SF and OMT combination treatment groups of mice. Also in SF and OMT combination treatment groups of rats, the increased lung W/D ratio and histopathological score induced by PQ injection were significantly decreased; the levels of CRP, IL-6, NF-κB and MDA in serum and lung homogenate were significantly decreased; the SOD activities in serum and lung homogenate were improved. These results suggested that SF and OMT combination had an obvious protective effect on PQ-induced lung injury. The anti-inflammatory and antioxidant effect might be involved in the mechanism. PMID:25901166

  19. Classification of cell death

    PubMed Central

    Kroemer, G; Galluzzi, L; Vandenabeele, P; Abrams, J; Alnemri, ES; Baehrecke, EH; Blagosklonny, MV; El-Deiry, WS; Golstein, P; Green, DR; Hengartner, M; Knight, RA; Kumar, S; Lipton, SA; Malorni, W; Nuñez, G; Peter, ME; Tschopp, J; Yuan, J; Piacentini, M; Zhivotovsky, B; Melino, G

    2009-01-01

    Different types of cell death are often defined by morphological criteria, without a clear reference to precise biochemical mechanisms. The Nomenclature Committee on Cell Death (NCCD) proposes unified criteria for the definition of cell death and of its different morphologies, while formulating several caveats against the misuse of words and concepts that slow down progress in the area of cell death research. Authors, reviewers and editors of scientific periodicals are invited to abandon expressions like ‘percentage apoptosis’ and to replace them with more accurate descriptions of the biochemical and cellular parameters that are actually measured. Moreover, at the present stage, it should be accepted that caspase-independent mechanisms can cooperate with (or substitute for) caspases in the execution of lethal signaling pathways and that ‘autophagic cell death’ is a type of cell death occurring together with (but not necessarily by) autophagic vacuolization. This study details the 2009 recommendations of the NCCD on the use of cell death-related terminology including ‘entosis’, ‘mitotic catastrophe’, ‘necrosis’, ‘necroptosis’ and ‘pyroptosis’. PMID:18846107

  20. The Protective Effect of Epigallocatechin-3-gallate on Paraquat-induced Haemolysis of Erythrocyte Membrane

    PubMed Central

    Moses, K; Pepple, D; Singh, P

    2015-01-01

    ABSTRACT Epigallocatechin-3-gallate (EGCG) is a major ingredient present in green tea, which has a high anti-oxidant activity. In this study, the effect of EGCG was investigated on paraquat-induced haemolysis of erythrocyte membrane. Erythrocytes were incubated in 0.03, 0.3, 3.0 and 30 mg/mL EGCG, respectively and exposed to 30 mg/mL of paraquat for 10 minutes. The effect of paraquat was determined by an analysis of the osmotic fragility of the erythrocytes. The results showed that EGCG (30 mg/mL) significantly (p < 0.05) reduced the haemolysis of erythrocytes exposed to paraquat (5.0 mg/mL). This suggests that EGCG may have a protective effect on paraquat-induced erythrocyte membrane haemolysis and that consumption of green tea, with high EGCG concentration, could ameliorate the deleterious effect of paraquat toxicity on the haemolysis of erythrocyte membrane. PMID:26426167

  1. Cardiac-Specific Knockout of ETA Receptor Mitigates Paraquat-Induced Cardiac Contractile Dysfunction.

    PubMed

    Wang, Jiaxing; Lu, Songhe; Zheng, Qijun; Hu, Nan; Yu, Wenjun; Li, Na; Liu, Min; Gao, Beilei; Zhang, Guoyong; Zhang, Yingmei; Wang, Haichang

    2016-07-01

    Paraquat (1,1'-dim ethyl-4-4'-bipyridinium dichloride), a highly toxic quaternary ammonium herbicide widely used in agriculture, exerts potent toxic prooxidant effects resulting in multi-organ failure including the lung and heart although the underlying mechanism remains elusive. Recent evidence suggests possible involvement of endothelin system in paraquat-induced acute lung injury. This study was designed to examine the role of endothelin receptor A (ETA) in paraquat-induced cardiac contractile and mitochondrial injury. Wild-type (WT) and cardiac-specific ETA receptor knockout mice were challenged to paraquat (45 mg/kg, i.p.) for 48 h prior to the assessment of echocardiographic, cardiomyocyte contractile and intracellular Ca(2+) properties, as well as apoptosis and mitochondrial damage. Levels of the mitochondrial proteins for biogenesis and oxidative phosphorylation including UCP2, HSP90 and PGC1α were evaluated. Our results revealed that paraquat elicited cardiac enlargement, mechanical anomalies including compromised echocardiographic parameters (elevated left ventricular end-systolic and end-diastolic diameters as well as reduced factional shortening), suppressed cardiomyocyte contractile function, intracellular Ca(2+) handling, overt apoptosis and mitochondrial damage. ETA receptor knockout itself failed to affect myocardial function, apoptosis, mitochondrial integrity and mitochondrial protein expression. However, ETA receptor knockout ablated or significantly attenuated paraquat-induced cardiac contractile and intracellular Ca(2+) defect, apoptosis and mitochondrial damage. Taken together, these findings revealed that endothelin system in particular the ETA receptor may be involved in paraquat-induced toxic myocardial contractile anomalies possibly related to apoptosis and mitochondrial damage. PMID:26089164

  2. Natural Antioxidant Betanin Protects Rats from Paraquat-Induced Acute Lung Injury Interstitial Pneumonia

    PubMed Central

    Ma, Deshun; Zhang, Miao; Yang, Xuelian; Tan, Dehong

    2015-01-01

    The effect of betanin on a rat paraquat-induced acute lung injury (ALI) model was investigated. Paraquat was injected intraperitoneally at a single dose of 20 mg/kg body weight, and betanin (25 and 100 mg/kg/d) was orally administered 3 days before and 2 days after paraquat administration. Rats were sacrificed 24 hours after the last betanin dosage, and lung tissue and bronchoalveolar lavage fluid (BALF) were collected. In rats treated only with paraquat, extensive lung injury characteristic of ALI was observed, including histological changes, elevation of lung : body weight ratio, increased lung permeability, increased lung neutrophilia infiltration, increased malondialdehyde (MDA) and myeloperoxidase (MPO) activity, reduced superoxide dismutase (SOD) activity, reduced claudin-4 and zonula occluden-1 protein levels, increased BALF interleukin (IL-1) and tumor necrosis factor (TNF)-α levels, reduced BALF IL-10 levels, and increased lung nuclear factor kappa (NF-κB) activity. In rats treated with betanin, paraquat-induced ALI was attenuated in a dose-dependent manner. In conclusion, our results indicate that betanin attenuates paraquat-induced ALI possibly via antioxidant and anti-inflammatory mechanisms. Thus, the potential for using betanin as an auxilliary therapy for ALI should be explored further. PMID:25861636

  3. Marked Recovery From Paraquat-Induced Lung Injury During Long-Term Follow-up

    PubMed Central

    Lee, Kwon-Hyun; Kim, Young-Tong; Yang, Jong-Oh; Lee, Eun-Young; Hong, Sae-Yong

    2009-01-01

    Background/Aims Paraquat-induced lung injury has been considered a progressive and irreversible disease. The purpose of this study was to report the long-term evolution of lung lesions in eight survivors with significant paraquat-induced lung injuries who could be followed-up for longer than 6 months. Methods We retrospectively examined high-resolution computed tomography and pulmonary function test of eight survivors with significant paraquat-induced lung injurys. Results High-resolution computed tomography revealed a predominant pattern of irregularly shaped consolidation with traction bronchiectasis at 1-2 months after paraquat poisoning, a mixed pattern of irregularly shaped consolidation and ground-glass opacity at 3-12 months, and a mixed pattern of consolidation, ground-glass opacity, and honeycombing at 1-2 years. At 3-12 months after paraquat ingestion, the areas of consolidation had markedly decreased and the decreased lung volume had returned to normal. At 1-2 years after paraquat poisoning, the cystic changes had disappeared. At 2-3 years after paraquat poisoning, the decrease in forced vital capacity had greatly improved to the normal range. Conclusions Recovery of nearly normal pulmonary structure and function may occur over several years following paraquat poisoning. Pulmonary function (both forced vital capacity and forced expiratory volume in 1 sec) evolved toward normal in the long-term survivors of paraquat poisoning with initial prominent lung injuries. PMID:19543486

  4. Betanin attenuates paraquat-induced liver toxicity through a mitochondrial pathway.

    PubMed

    Han, Junyan; Zhang, Zongju; Yang, Shaobin; Wang, Jun; Yang, Xuelian; Tan, Dehong

    2014-08-01

    We attempted to determine whether betanin (from natural pigments) that has anti-oxidant properties would be protective against paraquat-induced liver injury in Sprague-Dawley rats. Paraquat was injected intraperitoneally into rats to induce liver toxicity. The rats were randomly divided into four groups: a control group, a paraquat group, and two groups that received betanin at doses of 25 and 100mg/kg/day three days before and two days after they were administered paraquat. We evaluated liver histopathology, serum liver enzymatic activities, oxidative stress, cytochrome P450 (CYP) 3A2 mRNA expression, and mitochondrial damage. The rats that were injected with paraquat incurred liver injury, evidenced by histological changes and elevated serum aspartate aminotransferase and alanine aminotransferase levels; paraquat also led to oxidative stress, an increase of cytochrome P450 3A2 mRNA expression, and mitochondrial damage, indicated by mitochondrial membrane swelling, reduced mitochondrial cytochrome C, and apoptosis-inducing factor protein levels. Pathological damage and all of the above mentioned markers were lesser in the animals treated with betanin than in those who received paraquat alone. Betanin had a protective effect against paraquat-induced liver damage in rats. The mechanism of the protection appears to be the inhibition of CYP 3A2 expression and protection of mitochondria. PMID:24799198

  5. Cell death in mammalian development.

    PubMed

    Penaloza, C; Orlanski, S; Ye, Y; Entezari-Zaher, T; Javdan, M; Zakeri, Z

    2008-01-01

    During embryogenesis there is an exquisite orchestration of cellular division, movement, differentiation, and death. Cell death is one of the most important aspects of organization of the developing embryo, as alteration in timing, level, or pattern of cell death can lead to developmental anomalies. Cell death shapes the embryo and defines the eventual functions of the organs. Cells die using different paths; understanding which path a dying cell takes helps us define the signals that regulate the fate of the cell. Our understanding of cell death in development stems from a number of observations indicating genetic regulation of the death process. With today's increased knowledge of the pathways of cell death and the identification of the genes whose products regulate the pathways we know that, although elimination of some of these gene products has no developmental phenotype, alteration of several others has profound effects. In this review we discuss the types and distributions of cell death seen in developing mammalian embryos as well as the gene products that may regulate the process. PMID:18220829

  6. Cell death proteomics database: consolidating proteomics data on cell death.

    PubMed

    Arntzen, Magnus Ø; Bull, Vibeke H; Thiede, Bernd

    2013-05-01

    Programmed cell death is a ubiquitous process of utmost importance for the development and maintenance of multicellular organisms. More than 10 different types of programmed cell death forms have been discovered. Several proteomics analyses have been performed to gain insight in proteins involved in the different forms of programmed cell death. To consolidate these studies, we have developed the cell death proteomics (CDP) database, which comprehends data from apoptosis, autophagy, cytotoxic granule-mediated cell death, excitotoxicity, mitotic catastrophe, paraptosis, pyroptosis, and Wallerian degeneration. The CDP database is available as a web-based database to compare protein identifications and quantitative information across different experimental setups. The proteomics data of 73 publications were integrated and unified with protein annotations from UniProt-KB and gene ontology (GO). Currently, more than 6,500 records of more than 3,700 proteins are included in the CDP. Comparing apoptosis and autophagy using overrepresentation analysis of GO terms, the majority of enriched processes were found in both, but also some clear differences were perceived. Furthermore, the analysis revealed differences and similarities of the proteome between autophagosomal and overall autophagy. The CDP database represents a useful tool to consolidate data from proteome analyses of programmed cell death and is available at http://celldeathproteomics.uio.no. PMID:23537399

  7. The Preventive Effect of Atorvastatin on Paraquat-Induced Pulmonary Fibrosis in the Rats

    PubMed Central

    Khodayar, Mohammad Javad; Kiani, Milad; Hemmati, Ali Asghar; Rezaie, Anahita; Zerafatfard, Mohammad Rahim; Rashidi Nooshabadi, Mohammad Reza; Goudarzi, Mehdi

    2014-01-01

    Purpose: Pulmonary fibrosis is a potentially lethal inflammatory disease and there has been no effective medication for this progressive disease up to now. As a model, different therapeutic approaches have been applied for paraquat-induced pulmonary injury and fibrosis. Atorvastatin besides cholesterol-lowering effects possesses anti-inflammatory and anti-oxidant properties. The current study was designed to investigate the preventive anti-fibrotic effects of atorvastatin on paraquat-induced pulmonary fibrosis in rats. Methods: The rats were randomly divided into five experimental groups. Group I, control group (saline), group II received a single oral dose of 20 mg/kg paraquat with no treatment and III, IV and V groups received atorvastatin at the doses of 10, 20, and 40 mg/kg/day orally one week before and three weeks after paraquat administration, respectively. The rats were sacrificed 21 days after paraquat. Lung hydroxyproline and serum levels of malondialdehyde (MDA) were determined and lung indices and semi-quantitative histopathological changes were evaluated. Results: Paraquat could significantly increase the serum MDA and lung hydroxyproline levels. Elevated content of tissue hydroxyproline and serum levels of malondialdehyde induced by paraquat, attenuated by atorvastatin at the doses of 10, 20 and 40 mg/kg. Furthermore, histopathological findings and the amount of lung indices showed the beneficial preventive role of atorvastatin in rat pulmonary fibrosis induced by paraquat. Conclusion: In conclusion, the present data show that atorvastatin alleviate the toxic effects of paraquat under the experimental circumstances and may be a useful agent in cases who are in contact or poisoned with paraquat. PMID:25436189

  8. Autophagy, cell death, and cancer

    PubMed Central

    Lin, Lin; Baehrecke, Eric H

    2015-01-01

    Autophagy is an evolutionarily conserved intracellular catabolic process that is used by all cells to degrade dysfunctional or unnecessary cytoplasmic components through delivery to the lysosome. Increasing evidence reveals that autophagic dysfunction is associated with human diseases, such as cancer. Paradoxically, although autophagy is well recognized as a cell survival process that promotes tumor development, it can also participate in a caspase-independent form of programmed cell death. Induction of autophagic cell death by some anticancer agents highlights the potential of this process as a cancer treatment modality. Here, we review our current understanding of the molecular mechanism of autophagy and the potential roles of autophagy in cell death, cancer development, and cancer treatment. PMID:27308466

  9. Cell Death in Genome Evolution

    PubMed Central

    Teng, Xinchen; Hardwick, J. Marie

    2015-01-01

    Inappropriate survival of abnormal cells underlies tumorigenesis. Most discoveries about programmed cell death have come from studying model organisms. Revisiting the experimental contexts that inspired these discoveries helps explain confounding biases that inevitably accompany such discoveries. Amending early biases has added a newcomer to the collection of cell death models. Analysis of gene-dependent death in yeast revealed the surprising influence of single gene mutations on subsequent eukaryotic genome evolution. Similar events may influence the selection for mutations during early tumorigenesis. The possibility that an early random mutation might drive the selection for a cancer driver mutation is conceivable but difficult to demonstrate. This was tested in yeast, revealing that mutation of almost any gene appears to specify the selection for a new second mutation. Some human tumors contain pairs of mutant genes homologous to co-occurring mutant genes in yeast. Here we consider how yeast again provide novel insights into tumorigenesis. PMID:25725369

  10. Pancreatic β Cell Mass Death.

    PubMed

    Marrif, Husnia I; Al-Sunousi, Salma I

    2016-01-01

    Type two diabetes (T2D) is a challenging metabolic disorder for which a cure has not yet been found. Its etiology is associated with several phenomena, including significant loss of insulin-producing, beta cellcell) mass via progressive programmed cell death and disrupted cellular autophagy. In diabetes, the etiology of β cell death and the role of mitochondria are complex and involve several layers of mechanisms. Understanding the dynamics of those mechanisms could permit researchers to develop an intervention for the progressive loss of β cells. Currently, diabetes research has shifted toward rejuvenation and plasticity technology and away from the simplified approach of hormonal compensation. Diabetes research is currently challenged by questions such as how to enhance cell survival, decrease apoptosis and replenish β cell mass in diabetic patients. In this review, we discuss evidence that β cell development and mass formation are guided by specific signaling systems, particularly hormones, transcription factors, and growth factors, all of which could be manipulated to enhance mass growth. There is also strong evidence that β cells are dynamically active cells, which, under specific conditions such as obesity, can increase in size and subsequently increase insulin secretion. In certain cases of aggressive or advanced forms of T2D, β cells become markedly impaired, and the only alternatives for maintaining glucose homeostasis are through partial or complete cell grafting (the Edmonton protocol). In these cases, the harvesting of an enriched population of viable β cells is required for transplantation. This task necessitates a deep understanding of the pharmacological agents that affect β cell survival, mass, and function. The aim of this review is to initiate discussion about the important signals in pancreatic β cell development and mass formation and to highlight the process by which cell death occurs in diabetes. This review also examines the

  11. Pancreatic β Cell Mass Death

    PubMed Central

    Marrif, Husnia I.; Al-Sunousi, Salma I.

    2016-01-01

    Type two diabetes (T2D) is a challenging metabolic disorder for which a cure has not yet been found. Its etiology is associated with several phenomena, including significant loss of insulin-producing, beta cellcell) mass via progressive programmed cell death and disrupted cellular autophagy. In diabetes, the etiology of β cell death and the role of mitochondria are complex and involve several layers of mechanisms. Understanding the dynamics of those mechanisms could permit researchers to develop an intervention for the progressive loss of β cells. Currently, diabetes research has shifted toward rejuvenation and plasticity technology and away from the simplified approach of hormonal compensation. Diabetes research is currently challenged by questions such as how to enhance cell survival, decrease apoptosis and replenish β cell mass in diabetic patients. In this review, we discuss evidence that β cell development and mass formation are guided by specific signaling systems, particularly hormones, transcription factors, and growth factors, all of which could be manipulated to enhance mass growth. There is also strong evidence that β cells are dynamically active cells, which, under specific conditions such as obesity, can increase in size and subsequently increase insulin secretion. In certain cases of aggressive or advanced forms of T2D, β cells become markedly impaired, and the only alternatives for maintaining glucose homeostasis are through partial or complete cell grafting (the Edmonton protocol). In these cases, the harvesting of an enriched population of viable β cells is required for transplantation. This task necessitates a deep understanding of the pharmacological agents that affect β cell survival, mass, and function. The aim of this review is to initiate discussion about the important signals in pancreatic β cell development and mass formation and to highlight the process by which cell death occurs in diabetes. This review also examines the

  12. Metabolic control of cell death

    PubMed Central

    Green, Douglas R.; Galluzzi, Lorenzo; Kroemer, Guido

    2014-01-01

    Summary Beyond their contribution to basic metabolism, the major cellular organelles, in particular mitochondria, can determine whether cells respond to stress in an adaptive or suicidal manner. Thus, mitochondria can continuously adapt their shape to changing bioenergetic demands as they are subjected to quality control by autophagy, or they can undergo a lethal permeabilization process that initiates apoptosis. Along similar lines, multiple proteins involved in metabolic circuitries including oxidative phosphorylation and transport of metabolites across membranes may participate in the regulated or catastrophic dismantling of organelles. Many factors that were initially characterized as cell death regulators are now known to physically or functionally interact with metabolic enzymes. Thus, several metabolic cues regulate the propensity of cells to activate self-destructive programs, in part by acting on nutrient sensors. This suggests the existence of “metabolic checkpoints” that dictate cell fate in response to metabolic fluctuations. Here, we discuss recent insights into the intersection between metabolism and cell death regulation that have major implications for the comprehension and manipulation of unwarranted cell loss. PMID:25237106

  13. Cell death in the nervous system

    PubMed Central

    Bredesen, Dale E.; Rao, Rammohan V.; Mehlen, Patrick

    2014-01-01

    Neurodegenerative diseases such as Alzheimer’s disease and Parkinson’s disease trigger neuronal cell death through endogenous suicide pathways. Surprisingly, although the cell death itself may occur relatively late in the course of the degenerative process, the mediators of the underlying cell-death pathways have shown promise as potential therapeutic targets. PMID:17051206

  14. Cell death in the cardiovascular system

    PubMed Central

    Clarke, Murray; Bennett, Martin; Littlewood, Trevor

    2007-01-01

    Cell death is important for both development and tissue homeostasis in the adult. As such, it is tightly controlled and deregulation is associated with diverse pathologies; for example, regulated cell death is involved in vessel remodelling during development or following injury, but deregulated death is implicated in pathologies such as atherosclerosis, aneurysm formation, ischaemic and dilated cardiomyopathies and infarction. We describe the mechanisms of cell death and its role in the normal physiology and various pathologies of the cardiovascular system. PMID:16547202

  15. [Morphological and biochemical criteria for cell death].

    PubMed

    Chernikov, V P; Belousova, T A; Kakturskiĭ, L V

    2010-01-01

    The state-of-the-art of classifications of and criteria for cell death in the light of the 2009 recommendations of the Nomenclature Committee on Cell Death is presented as a lecture. Motivation is given for the necessity of using the unified criteria in the description of cell death and more than one study in its verification. The major structural and biochemical signs of four typical types of cell death--apoptosis, autophagia, keratinization, and necrosis are compared. Data are given on the major atypical forms of cell death--mitotic catastrophe, anoikis, exitotoxicity, Wallerian degeneration, paraptosis, pyroptosis, pyronecrosis, and entosis. PMID:20734836

  16. Pathogen Tactics to Manipulate Plant Cell Death.

    PubMed

    Mukhtar, M Shahid; McCormack, Maggie E; Argueso, Cristiana T; Pajerowska-Mukhtar, Karolina M

    2016-07-11

    Cell death is a vital process for multicellular organisms. Programmed cell death (PCD) functions in a variety of processes including growth, development, and immune responses for homeostasis maintenance. In particular, plants and animals utilize PCD to control pathogen invasion and infected cell populations. Despite some similarity, there are a number of key differences between how these organisms initiate and regulate cell death. In contrast to animals, plants are sessile, lack a circulatory system, and have additional cellular structures, including cell walls and chloroplasts. Plant cells have the autonomous ability to induce localized cell death using conserved eukaryotic pathways as well as unique plant-specific pathways. Thus, in order to successfully infect host cells, pathogens must subvert immune responses and avoid detection to prevent PCD and allow infection. Here we discuss the roles of cell death in plant immune responses and the tactics pathogens utilize to avert cell death. PMID:27404256

  17. How cell death shapes cancer

    PubMed Central

    Labi, V; Erlacher, M

    2015-01-01

    Apoptosis has been established as a mechanism of anti-cancer defense. Members of the BCL-2 family are critical mediators of apoptotic cell death in health and disease, often found to be deregulated in cancer and believed to lead to the survival of malignant clones. However, over the years, a number of studies pointed out that a model in which cell death resistance unambiguously acts as a barrier against malignant disease might be too simple. This is based on paradoxical observations made in tumor patients as well as mouse models indicating that apoptosis can indeed drive tumor formation, at least under certain circumstances. One possible explanation for this phenomenon is that apoptosis can promote proliferation critically needed to compensate for cell loss, for example, upon therapy, and to restore tissue homeostasis. However, this, at the same time, can promote tumor development by allowing expansion of selected clones. Usually, tissue resident stem/progenitor cells are a major source for repopulation, some of them potentially carrying (age-, injury- or therapy-induced) genetic aberrations deleterious for the host. Thereby, apoptosis might drive genomic instability by facilitating the emergence of pathologic clones during phases of proliferation and subsequent replication stress-associated DNA damage. Tumorigenesis initiated by repeated cell attrition and repopulation, as confirmed in different genetic models, has parallels in human cancers, exemplified in therapy-induced secondary malignancies and myelodysplastic syndromes in patients with congenital bone marrow failure syndromes. Here, we aim to review evidence in support of the oncogenic role of stress-induced apoptosis. PMID:25741600

  18. Apoptotic Cell Death in Neuroblastoma

    PubMed Central

    Li, Yuanyuan; Nakagawara, Akira

    2013-01-01

    Neuroblastoma (NB) is one of the most common malignant solid tumors in childhood, which derives from the sympathoadrenal lineage of the neural crest and exhibits extremely heterogeneous biological and clinical behaviors. The infant patients frequently undergo spontaneous regression even with metastatic disease, whereas the patients of more than one year of age who suffer from disseminated disease have a poor outcome despite intensive multimodal treatment. Spontaneous regression in favorable NBs has been proposed to be triggered by nerve growth factor (NGF) deficiency in the tumor with NGF dependency for survival, while aggressive NBs have defective apoptotic machinery which enables the tumor cells to evade apoptosis and confers the resistance to treatment. This paper reviews the molecules and pathways that have been recently identified to be involved in apoptotic cell death in NB and discusses their potential prospects for developing more effective therapeutic strategies against aggressive NB. PMID:24709709

  19. Effects of Different Tidal Volume Ventilation on Paraquat-Induced Acute Lung Injury in Piglets

    PubMed Central

    Lan, Chao; Wang, Jinzhu; Li, Li; Li, Haina; Li, Lu; Su, Qianqian; Che, Lu; Liu, Lanping; Di, Min

    2015-01-01

    Background The aim of this study was to explore the effects of different tidal volume (VT) ventilation on paraquat-induced acute lung injury or acute respiratory distress syndrome (ALI/ARDS) in piglets. Material/Methods We developed ALI/ARDS models in piglets by intraperitoneal injection of paraquat (PQ). The piglets were randomly divided into three groups: small VT group (VT=6 ml/kg, n=6), middle VT group (VT=10 ml/kg, n=6), and large VT group (VT=15 ml/kg, n=6), with the positive end-expiratory pressure (PEEP) set as 10 cmH2O. The hemodynamics were monitored by pulse-indicated continuous cardiac output (PiCCO) and the airway pressure changes and blood gas analysis indexes were recorded at different time points. The pathological changes were observed by lung puncture. Results The piglets showed ALI/ARDS in 4.5±0.8 hours after PQ intraperitoneal injection. PH, PaO2 and oxygenation indexes in the three groups all decreased after modeling success compared with baseline, and PaCO2 increased significantly. PH in the small VT group decreased most obviously after ventilation for 6 hours. PaO2 and oxygenation indexes in the small VT group showed the most obvious increase after ventilation for 2 hours and were much higher than the other two groups after ventilation for 6 hours. PaCO2 increased gradually after mechanical ventilation and the small VT group showed most obvious increase. The ELWI increased obviously after ventilation for 2 hours and then the small VT group clearly decreased. PIP and plateau pressure (Pplat) in the small VT group decreased gradually and in the middle and large VT group they increased after ventilation. The lung histopathology showed that the large VT group had the most severe damage and the small VT group had only minimal damage. Conclusions Small tidal volume ventilation combined with PEEP could alleviate the acute lung injury induced by paraquat and improve oxygenation. PMID:25671690

  20. Detection of Cell Death in Drosophila Tissues

    PubMed Central

    Vasudevan, Deepika; Ryoo, Hyung Don

    2016-01-01

    Drosophila has served as a particularly attractive model to study cell death due to the vast array of tools for genetic manipulation under defined spatial and temporal conditions in vivo as well as in cultured cells. These genetic methods have been well supplemented by enzymatic assays and a panel of antibodies recognizing cell death markers. This chapter discusses reporters, mutants and assays used by various laboratories to study cell death in the context of development and in response to external insults. PMID:27108437

  1. What cell death does in development.

    PubMed

    Zakeri, Zahra; Penaloza, Carlos G; Smith, Kyle; Ye, Yixia; Lockshin, Richard A

    2015-01-01

    Cell death is prominent in gametogenesis and shapes and sculpts embryos. In non-mammalian embryos one sees little or no cell death prior to the maternal-zygotic transition, but, in mammalian embryos, characteristic deaths of one or two cells occur at the end of compaction and are apparently necessary for the separation of the trophoblast from the inner cell mass. Considerable sculpting of the embryo occurs by cell deaths during organogenesis, and appropriate cell numbers, especially in the CNS and in the immune system, are generated by massive overproduction of cells and selection of a few, with death of the rest. The timing, identity, and genetic control of specific cells that die have been well documented in Caenorhabditis, but in other embryos the stochastic nature of the deaths limit our ability to do more than identify the regions in which cells will die. Complete disruption of the cell death machinery can be lethal, but many mutations of the regulatory machinery yield only modest or no phenotypes, indicating substantial redundancy and compensation of regulatory mechanisms. Most of the deaths are apoptotic and are identified by techniques used to recognize apoptosis, but techniques identifying lysosomes (whether in dying or involuting cells or in the phagocytes that invade the tissue) also reveal patterns of cell death. Aberrant cell deaths that produce known phenotypes are typically localized, indicating that the mechanism of activating a programmed death in a specific region, rather than the mechanism of death, is aberrant. These results lead us to conclude that we need to know much more about the conversations among cells that lead cells to commit suicide. PMID:26374521

  2. Molecular definitions of cell death subroutines: recommendations of the Nomenclature Committee on Cell Death 2012

    PubMed Central

    Galluzzi, L; Vitale, I; Abrams, J M; Alnemri, E S; Baehrecke, E H; Blagosklonny, M V; Dawson, T M; Dawson, V L; El-Deiry, W S; Fulda, S; Gottlieb, E; Green, D R; Hengartner, M O; Kepp, O; Knight, R A; Kumar, S; Lipton, S A; Lu, X; Madeo, F; Malorni, W; Mehlen, P; Nuñez, G; Peter, M E; Piacentini, M; Rubinsztein, D C; Shi, Y; Simon, H-U; Vandenabeele, P; White, E; Yuan, J; Zhivotovsky, B; Melino, G; Kroemer, G

    2012-01-01

    In 2009, the Nomenclature Committee on Cell Death (NCCD) proposed a set of recommendations for the definition of distinct cell death morphologies and for the appropriate use of cell death-related terminology, including ‘apoptosis', ‘necrosis' and ‘mitotic catastrophe'. In view of the substantial progress in the biochemical and genetic exploration of cell death, time has come to switch from morphological to molecular definitions of cell death modalities. Here we propose a functional classification of cell death subroutines that applies to both in vitro and in vivo settings and includes extrinsic apoptosis, caspase-dependent or -independent intrinsic apoptosis, regulated necrosis, autophagic cell death and mitotic catastrophe. Moreover, we discuss the utility of expressions indicating additional cell death modalities. On the basis of the new, revised NCCD classification, cell death subroutines are defined by a series of precise, measurable biochemical features. PMID:21760595

  3. Programmed Cell Death During Caenorhabditis elegans Development.

    PubMed

    Conradt, Barbara; Wu, Yi-Chun; Xue, Ding

    2016-08-01

    Programmed cell death is an integral component of Caenorhabditis elegans development. Genetic and reverse genetic studies in C. elegans have led to the identification of many genes and conserved cell death pathways that are important for the specification of which cells should live or die, the activation of the suicide program, and the dismantling and removal of dying cells. Molecular, cell biological, and biochemical studies have revealed the underlying mechanisms that control these three phases of programmed cell death. In particular, the interplay of transcriptional regulatory cascades and networks involving multiple transcriptional regulators is crucial in activating the expression of the key death-inducing gene egl-1 and, in some cases, the ced-3 gene in cells destined to die. A protein interaction cascade involving EGL-1, CED-9, CED-4, and CED-3 results in the activation of the key cell death protease CED-3, which is tightly controlled by multiple positive and negative regulators. The activation of the CED-3 caspase then initiates the cell disassembly process by cleaving and activating or inactivating crucial CED-3 substrates; leading to activation of multiple cell death execution events, including nuclear DNA fragmentation, mitochondrial elimination, phosphatidylserine externalization, inactivation of survival signals, and clearance of apoptotic cells. Further studies of programmed cell death in C. elegans will continue to advance our understanding of how programmed cell death is regulated, activated, and executed in general. PMID:27516615

  4. Toll-like receptor 4 knockout alleviates paraquat-induced cardiomyocyte contractile dysfunction through an autophagy-dependent mechanism.

    PubMed

    Wang, Shuyi; Zhu, Xiaoling; Xiong, Lize; Zhang, Yingmei; Ren, Jun

    2016-08-22

    Paraquat, a quarternary nitrogen herbicide, is a toxic prooxidant leading to multi-organ failure including the heart although the underlying mechanism remains poorly understood. This study was designed to examine the role of the innate proinflammatory mediator toll-like receptor 4 (TLR4) in paraquat-induced cardiac contractile anomalies and the underlying mechanisms involved with a focus on autophagy, a conservative machinery governing protein and organelle degradation and recycling for cardiac homeostasis. Wild-type (WT) and TLR4 knockout (TLR4(-/-)) mice were challenged with paraquat (45mg/kg, i.p.) for 48h. Paraquat challenge did not affect mRNA levels of TLR2, TLR4 and TLR9 in WT mice nor did paraquat treatment alter TREM-1 levels. Paraquat challenge elicited cardiac mechanical defects including compromised cardiomyocyte contractile function, intracellular Ca(2+) handling, and overt autophagy as manifested by increased LC3BII-to-LC3BI ratio, Atg5, Atg7 and p62 levels. Interestingly, TLR4 knockout significantly attenuated paraquat-induced cardiac contractile and intracellular Ca(2+) derangement as well as alterations of autophagy markers. Paraquat-elicited changes in cardiac autophagy markers (LC3BII, LC3BII-to-LC3BI ratio and p62) were augmented by lysosomal inhibition using bafilomycin A1 in WT mice. TLR4 knockout significantly attenuated or negated paraquat-elicited increase in LC3BII, LC3BII-to-LC3BI ratio and p62 levels in the presence of lysosomal inhibition. In addition, paraquat challenge promoted phosphorylation of AMPK while suppressing the phosphorylation of mTOR and ULK1 (the autophagy inhibitory Ser(757)), the effects of which were significantly attenuated by TLR4 ablation. In vitro study revealed that AMPK activation using AICAR or mTOR inhibition using rapamycin effectively negated the beneficial cardiomyocyte mechanical effects of TLR4 inhibition (CLI-095) against paraquat toxicity, supporting a permissive role for AMPK-mTOR in TLR4 inhibition

  5. Cell death regulates muscle fiber number.

    PubMed

    Sarkissian, Tatevik; Arya, Richa; Gyonjyan, Seda; Taylor, Barbara; White, Kristin

    2016-07-01

    Cell death can have both cell autonomous and non-autonomous roles in normal development. Previous studies have shown that the central cell death regulators grim and reaper are required for the developmentally important elimination of stem cells and neurons in the developing central nervous system (CNS). Here we show that cell death in the nervous system is also required for normal muscle development. In the absence of grim and reaper, there is an increase in the number of fibers in the ventral abdominal muscles in the Drosophila adult. This phenotype can be partially recapitulated by inhibition of cell death specifically in the CNS, indicating a non-autonomous role for neuronal death in limiting muscle fiber number. We also show that FGFs produced in the cell death defective nervous system are required for the increase in muscle fiber number. Cell death in the muscle lineage during pupal stages also plays a role in specifying fiber number. Our work suggests that FGFs from the CNS act as a survival signal for muscle founder cells. Thus, proper muscle fiber specification requires cell death in both the nervous system and in the developing muscle itself. PMID:27131625

  6. Nonthermal-plasma-mediated animal cell death

    NASA Astrophysics Data System (ADS)

    Kim, Wanil; Woo, Kyung-Chul; Kim, Gyoo-Cheon; Kim, Kyong-Tai

    2011-01-01

    Animal cell death comprising necrosis and apoptosis occurred in a well-regulated manner upon specific stimuli. The physiological meanings and detailed molecular mechanisms of cell death have been continuously investigated over several decades. Necrotic cell death has typical morphological changes, such as cell swelling and cell lysis followed by DNA degradation, whereas apoptosis shows blebbing formation and regular DNA fragmentation. Cell death is usually adopted to terminate cancer cells in vivo. The current strategies against tumour are based on the induction of cell death by adopting various methods, including radiotherapy and chemotherapeutics. Among these, radiotherapy is the most frequently used treatment method, but it still has obvious limitations. Recent studies have suggested that the use of nonthermal air plasma can be a prominent method for inducing cancer cell death. Plasma-irradiated cells showed the loss of genomic integrity, mitochondrial dysfunction, plasma membrane damage, etc. Tumour elimination with plasma irradiation is an emerging concept in cancer therapy and can be accelerated by targeting certain tumour-specific proteins with gold nanoparticles. Here, some recent developments are described so that the mechanisms related to plasma-mediated cell death and its perspectives in cancer treatment can be understood.

  7. [Programmed cell death comes in many flavors].

    PubMed

    Cabon, Lauriane; Martinez-Torres, Ana-Carolina; Susin, Santos A

    2013-12-01

    Apoptosis is nowadays what comes first to your scientist mind when someone mentions cellular suicide. However this is not the sole form of programmed cell death and many other alternative or atypical pathways have now been described. These pathways are indeed rather preferred to apoptosis in some instances based on tissue origin, cell type or development stage of the target cell. In this review, we describe many different programmed cell death subtypes according to their characteristics. Discrete, brutal, final or singular cell death pathways all participate in the elimination of unwanted, damaged or dangerous cells in organisms hence contributing to our knowledge of this particular feature of living beings: dying! Through description of anoikis, necroptosis, entosis, netosis, pyroptosis or ferroptosis, we have no choice but to realize that programmed cell death comes in many flavors. PMID:24356142

  8. Joint aging and chondrocyte cell death

    PubMed Central

    Grogan, Shawn P; D’Lima, Darryl D

    2010-01-01

    Articular cartilage extracellular matrix and cell function change with age and are considered to be the most important factors in the development and progression of osteoarthritis. The multifaceted nature of joint disease indicates that the contribution of cell death can be an important factor at early and late stages of osteoarthritis. Therefore, the pharmacologic inhibition of cell death is likely to be clinically valuable at any stage of the disease. In this article, we will discuss the close association between diverse changes in cartilage aging, how altered conditions influence chondrocyte death, and the implications of preventing cell loss to retard osteoarthritis progression and preserve tissue homeostasis. PMID:20671988

  9. Cell death independent of caspases: a review.

    PubMed

    Bröker, Linda E; Kruyt, Frank A E; Giaccone, Giuseppe

    2005-05-01

    Patterns of cell death have been divided into apoptosis, which is actively executed by specific proteases, the caspases, and accidental necrosis. However, there is now accumulating evidence indicating that cell death can occur in a programmed fashion but in complete absence and independent of caspase activation. Alternative models of programmed cell death (PCD) have therefore been proposed, including autophagy, paraptosis, mitotic catastrophe, and the descriptive model of apoptosis-like and necrosis-like PCD. Caspase-independent cell death pathways are important safeguard mechanisms to protect the organism against unwanted and potential harmful cells when caspase-mediated routes fail but can also be triggered in response to cytotoxic agents or other death stimuli. As in apoptosis, the mitochondrion can play a key role but also other organelles such as lysosomes and the endoplasmic reticulum have an important function in the release and activation of death factors such as cathepsins, calpains, and other proteases. Here we review the various models of PCD and their death pathways at molecular and organelle level and discuss the relevance of the growing knowledge of caspase-independent cell death pathways for cancer. PMID:15867207

  10. Staying alive: cell death in antiviral immunity.

    PubMed

    Upton, Jason W; Chan, Francis Ka-Ming

    2014-04-24

    Programmed cell death is an integral part of host defense against invading intracellular pathogens. Apoptosis, programmed necrosis, and pyroptosis each serve to limit pathogen replication in infected cells, while simultaneously promoting the inflammatory and innate responses that shape effective long-term host immunity. The importance of carefully regulated cell death is evident in the spectrum of inflammatory and autoimmune disorders caused by defects in these pathways. Moreover, many viruses encode inhibitors of programmed cell death to subvert these host responses during infection, thereby facilitating their own replication and persistence. Thus, as both virus and cell vie for control of these pathways, the battle for survival has shaped a complex host-pathogen interaction. This review will discuss the multifaceted role that programmed cell death plays in maintaining the immune system and its critical function in host defense, with a special emphasis on viral infections. PMID:24766891

  11. Plant Proteases Involved in Regulated Cell Death.

    PubMed

    Zamyatnin, A A

    2015-12-01

    Each plant genome encodes hundreds of proteolytic enzymes. These enzymes can be divided into five distinct classes: cysteine-, serine-, aspartic-, threonine-, and metalloproteinases. Despite the differences in their structural properties and activities, members of all of these classes in plants are involved in the processes of regulated cell death - a basic feature of eukaryotic organisms. Regulated cell death in plants is an indispensable mechanism supporting plant development, survival, stress responses, and defense against pathogens. This review summarizes recent advances in studies of plant proteolytic enzymes functioning in the initiation and execution of distinct types of regulated cell death. PMID:26878575

  12. Entosis and Related Forms of Cell Death within Cells.

    PubMed

    Wang, Y; Wang, X-D

    2015-01-01

    By eliminating the unneeded or mutant cells, programmed cell death actively participates in a wide range of biological processes from embryonic development to homeostasis maintenance in adult. Continuing efforts have identified multiple cell death pathways, with apoptosis, necrosis and autophage the mostly studied. Recently a unique cell death pathway called "cell-in-cell death" has been defined. Unlike traditional cell death pathways, cell-in-cell death, characterized by cell death within another cell, is triggered by the invasion of one cell into its neighbor and executed by either lysosome-dependent degradation or caspase-dependent apoptosis. With remarkable progresses on cell-in-cell over past few years, multiple mechanisms, including entosis, cannibalism and emperitosis, are found to be responsible for cell-in-cell death. Some key questions, such as specific biochemical markers to distinguish precisely the properties of different cell-in-cell structures and the physiological and pathological relevance, remain to be addressed. In light of this situation and a surge of interests, leading scientists in this field intend to share with readers current research progresses on cell-in-cell structures from different model systems through this special edition on cell-in-cell. The mechanistic advances will be highlighted while the future researches be speculated. PMID:26511710

  13. Mitochondrial Cell Death Pathways in Caenorhabiditis elegans.

    PubMed

    Seervi, Mahendra; Xue, Ding

    2015-01-01

    Programmed cell death is an evolutionarily conserved process essential for animal development and tissue homeostasis. Mitochondria have been demonstrated to play a central role in regulating both the activation and the execution of apoptosis. In particular, mitochondria release multiple proapoptotic factors from its intermembrane space, leading to both caspase-dependent and -independent cell death. Despite the pivotal roles of invertebrate animal models, Caenorhabiditis elegans and Drosophila melanogaster, in deciphering conserved pathways and mechanisms of programmed cell death, the importance of mitochondria to apoptosis of invertebrates remains elusive and largely unexplored. Recent studies have corroborated significant association between mitochondria and apoptosis in C. elegans, making it a thrust area of investigations. In this review, we detail the roles of mitochondrial proteins in mediating execution of cell death in C. elegans, including chromosome fragmentation, phosphatidylserine externalization, and elimination of mitochondria, and discuss the potential roles of mitochondria in the activation of C. elegans cell death. The combination of traditional powerful genetic tools and the emergence of the multiple new reverse genetic techniques, including the highly efficient CRISPR/Cas9 gene-editing method, should make C. elegans an ideal animal model for analyzing mitochondrial cell death pathways and associated regulatory mechanisms. PMID:26431563

  14. Cell death in the developing vertebrate retina.

    PubMed

    Vecino, Elena; Hernández, María; García, Mónica

    2004-01-01

    Programmed cell death occurs naturally, as a physiological process, during the embryonic development of multicellular organisms. In the retina, which belongs to the central nervous system, at least two phases of cell death have been reported to occur during development. An early phase takes place concomitant with the processes of neurogenesis, cell migration and cell differentiation. A later phase affecting mainly neurons occurs when connections are established and synapses are formed, resulting in selective elimination of inappropriate connections. This pattern of cell death in the developing retina is common among different vertebrates. However, the timing and magnitude of retinal cell death varies among species. In addition, a precise regulation of apoptosis during retinal development has been described. Factors such as neurotrophins, among many others, and electrical activity influence the survival of retinal cells during the course of development. In this paper, we present a summary of these different aspects of programmed cell death during retinal development, and examine how these differ among different species. PMID:15558487

  15. Regulation of Cell Death by Transfer RNA

    PubMed Central

    2013-01-01

    Abstract Significance: Both transfer RNA (tRNA) and cytochrome c are essential molecules for the survival of cells. tRNA decodes mRNA codons into amino-acid-building blocks in protein in all organisms, whereas cytochrome c functions in the electron transport chain that powers ATP synthesis in mitochondrion-containing eukaryotes. Additionally, in vertebrates, cytochrome c that is released from mitochondria is a potent inducer of apoptosis, activating apoptotic proteins (caspases) in the cytoplasm to dismantle cells. A better understanding of both tRNA and cytochrome c is essential for an insight into the regulation of cell life and death. Recent Advances: A recent study showed that the mitochondrion-released cytochrome c can be removed from the cell-death pathway by tRNA molecules. The direct binding of cytochrome c by tRNA provides a mechanism for tRNA to regulate cell death, beyond its role in gene expression. Critical Issues: The nature of the tRNA–cytochrome c binding interaction remains unknown. The questions of how this interaction affects tRNA function, cellular metabolism, and apoptotic sensitivity are unanswered. Future Directions: Investigations into the critical issues raised above will improve the understanding of tRNA in the fundamental processes of cell death and metabolism. Such knowledge will inform therapies in cell death-related diseases. Antioxid. Redox Signal. 19, 583–594. PMID:23350625

  16. Programmed cell death: many ways for cells to die decently.

    PubMed

    Jäättelä, Marja

    2002-01-01

    Apoptosis, a cell death programme mediated by the caspase family of cysteine proteases, is essential for appropriate removal of excess cells in many developmental and physiological settings. It would, however, be very dangerous for the organism to depend on a single protease family for clearance of unwanted and potentially dangerous cells. Indeed, the exclusive role of caspases in the execution of programmed cell death (PCD) has been challenged recently, and the understanding of the molecular control of alternative death pathways is emerging. Here, I review recently discovered triggers and molecular regulators of caspase-independent cell death programmes and discuss their potential as therapeutic targets for the treatment of cancer. PMID:12523503

  17. Inflammasomes as polyvalent cell death platforms.

    PubMed

    de Vasconcelos, Nathalia M; Van Opdenbosch, Nina; Lamkanfi, Mohamed

    2016-06-01

    Inflammasomes are multi-protein platforms that are organized in the cytosol to cope with pathogens and cellular stress. The pattern recognition receptors NLRP1, NLRP3, NLRC4, AIM2 and Pyrin all assemble canonical platforms for caspase-1 activation, while caspase-11-dependent inflammasomes respond to intracellular Gram-negative pathogens. Inflammasomes are chiefly known for their roles in maturation and secretion of the inflammatory cytokines interleukin-(IL)1β and IL18, but they can also induce regulated cell death. Activation of caspases 1 and 11 in myeloid cells can trigger pyroptosis, a lytic and inflammatory cell death mode. Pyroptosis has been implicated in secretion of IL1β, IL18 and intracellular alarmins. Akin to these factors, it may have beneficial roles in controlling pathogen replication, but become detrimental in the context of chronic autoinflammatory diseases. Inflammasomes are increasingly implicated in induction of additional regulated cell death modes such as pyronecrosis and apoptosis. In this review, we overview recent advances in inflammasome-associated cell death research, illustrating the polyvalent roles of these macromolecular platforms in regulated cell death signaling. PMID:27048821

  18. Apoptotic cell death induced by intracellular proteolysis.

    PubMed

    Williams, M S; Henkart, P A

    1994-11-01

    To mimic the injection of granzymes into target cells by cytotoxic lymphocytes or the activation of endogenous proteases in programmed cell death, the proteases chymotrypsin, proteinase K, or trypsin were loaded into the cytoplasm of several different cell types using the osmotic lysis of pinosomes technique. Internalization of these proteases caused cell lysis within several hours, accompanied by extensive nuclear damage in most but not all combinations of target cells and proteases. This nuclear damage, quantitated by DNA release from nuclei, was associated with apoptotic features including DNA fragmentation into nucleosomal ladders, chromatin condensation, nuclear fragmentation, and membrane blebbing. Agents reported to block programmed cell death, including aurintricarboxylic acid, inhibitors of energy metabolism, and protein or RNA synthesis, failed to block this protease-induced death, although some inhibited nuclear damage. In separate experiments, introduction of staphylococcal nuclease into cells led to near complete (at least 75% of total) nucleosomal DNA fragmentation within 6 to 8 h. Condensation of chromatin did not accompany this fragmentation to the same extent, and there was approximately a 10-h lag between half-maximal DNA fragmentation and 50% loss of membrane integrity. The results suggest that activation of intracellular proteases during cell death by any molecular pathway could give rise to apoptotic morphology and DNA fragmentation. PMID:7930626

  19. Parvovirus infection-induced cell death and cell cycle arrest

    PubMed Central

    Chen, Aaron Yun; Qiu, Jianming

    2011-01-01

    The cytopathic effects induced during parvovirus infection have been widely documented. Parvovirus infection-induced cell death is often directly associated with disease outcomes (e.g., anemia resulting from loss of erythroid progenitors during parvovirus B19 infection). Apoptosis is the major form of cell death induced by parvovirus infection. However, nonapoptotic cell death, namely necrosis, has also been reported during infection of the minute virus of mice, parvovirus H-1 and bovine parvovirus. Recent studies have revealed multiple mechanisms underlying the cell death during parvovirus infection. These mechanisms vary in different parvoviruses, although the large nonstructural protein (NS)1 and the small NS proteins (e.g., the 11 kDa of parvovirus B19), as well as replication of the viral genome, are responsible for causing infection-induced cell death. Cell cycle arrest is also common, and contributes to the cytopathic effects induced during parvovirus infection. While viral NS proteins have been indicated to induce cell cycle arrest, increasing evidence suggests that a cellular DNA damage response triggered by an invading single-stranded parvoviral genome is the major inducer of cell cycle arrest in parvovirus-infected cells. Apparently, in response to infection, cell death and cell cycle arrest of parvovirus-infected cells are beneficial to the viral cell lifecycle (e.g., viral DNA replication and virus egress). In this article, we will discuss recent advances in the understanding of the mechanisms underlying parvovirus infection-induced cell death and cell cycle arrest. PMID:21331319

  20. How Kidney Cell Death Induces Renal Necroinflammation.

    PubMed

    Mulay, Shrikant R; Kumar, Santhosh V; Lech, Maciej; Desai, Jyaysi; Anders, Hans-Joachim

    2016-05-01

    The nephrons of the kidney are independent functional units harboring cells of a low turnover during homeostasis. As such, physiological renal cell death is a rather rare event and dead cells are flushed away rapidly with the urinary flow. Renal cell necrosis occurs in acute kidney injuries such as thrombotic microangiopathies, necrotizing glomerulonephritis, or tubular necrosis. All of these are associated with intense intrarenal inflammation, which contributes to further renal cell loss, an autoamplifying process referred to as necroinflammation. But how does renal cell necrosis trigger inflammation? Here, we discuss the role of danger-associated molecular patterns (DAMPs), mitochondrial (mito)-DAMPs, and alarmins, as well as their respective pattern recognition receptors. The capacity of DAMPs and alarmins to trigger cytokine and chemokine release initiates the recruitment of leukocytes into the kidney that further amplify necroinflammation. Infiltrating neutrophils often undergo neutrophil extracellular trap formation associated with neutrophil death or necroptosis, which implies a release of histones, which act not only as DAMPs but also elicit direct cytotoxic effects on renal cells, namely endothelial cells. Proinflammatory macrophages and eventually cytotoxic T cells further drive kidney cell death and inflammation. Dissecting the molecular mechanisms of necroinflammation may help to identify the best therapeutic targets to limit nephron loss in kidney injury. PMID:27339382

  1. Time-Lapse Imaging of Cell Death.

    PubMed

    Wallberg, Fredrik; Tenev, Tencho; Meier, Pascal

    2016-03-01

    The best approach to distinguish between necrosis and apoptosis is time-lapse video microscopy. This technique enables a biological process to be photographed at regular intervals over a period, which may last from a few hours to several days, and can be applied to cells in culture or in vivo. We have established two time-lapse microscopy methods based on different ways of calculating cell death: semiautomated and automated. In the semiautomated approach, cell death can be visualized by staining with combinations of Alexa Fluor 647-conjugated Annexin V and Sytox Green (SG), or Annexin V(FITC) and Propidium iodide (PI). The automated method is similar except that all cells are labeled with dyes. This allows faster quantification of data. To this end Cell Tracker Green is used to label all cells at time zero in combination with PI and Alexa Fluor 647-conjugated Annexin V. Necrotic cell death is accompanied by either simultaneous labeling with Annexin V and PI or SG (double-positive), or direct PI or SG staining. Additionally, necrotic cells display characteristic morphology, such as cytoplasmic swelling. In contrast to necrosis where membrane permeabilization is an early event, cells that die by apoptosis lose their membrane permeability relatively late. Therefore, the time between Annexin V staining and PI or SG uptake (double-positive) can be used to distinguish necrosis from apoptosis. This protocol describes the analysis of cell death by time-lapse imaging of HT1080 and L929 cells stained with these dyes, but it can be readily adapted to other cell types of interest. PMID:26933245

  2. Optogenetic apoptosis: light-triggered cell death.

    PubMed

    Hughes, Robert M; Freeman, David J; Lamb, Kelsey N; Pollet, Rebecca M; Smith, Weston J; Lawrence, David S

    2015-10-01

    An optogenetic Bax has been designed that facilitates light-induced apoptosis. We demonstrate that mitochondrial recruitment of a genetically encoded light-responsive Bax results in the release of mitochondrial proteins, downstream caspase-3 cleavage, changes in cellular morphology, and ultimately cell death. Mutagenesis of a key phosphorylatable residue or modification of the C-terminus mitigates background (dark) levels of apoptosis that result from Bax overexpression. The mechanism of optogenetic Bax-mediated apoptosis was explored using a series of small molecules known to interfere with various steps in programmed cell death. Optogenetic Bax appears to form a mitochondrial apoptosis-induced channel analogous to that of endogenous Bax. PMID:26418181

  3. ETosis: A Microbicidal Mechanism beyond Cell Death

    PubMed Central

    Guimarães-Costa, Anderson B.; Nascimento, Michelle T. C.; Wardini, Amanda B.; Pinto-da-Silva, Lucia H.; Saraiva, Elvira M.

    2012-01-01

    Netosis is a recently described type of neutrophil death occurring with the release to the extracellular milieu of a lattice composed of DNA associated with histones and granular and cytoplasmic proteins. These webs, initially named neutrophil extracellular traps (NETs), ensnare and kill microorganisms. Similarly, other cell types, such as eosinophils, mast cells, and macrophages, can also dye by this mechanism; thus, it was renamed as ETosis, meaning death with release of extracellular traps (ETs). Here, we review the mechanism of NETosis/etosis, emphasizing its role in diseases caused by protozoan parasites, fungi, and viruses. PMID:22536481

  4. Regulated cell death and adaptive stress responses.

    PubMed

    Galluzzi, Lorenzo; Bravo-San Pedro, José Manuel; Kepp, Oliver; Kroemer, Guido

    2016-06-01

    Eukaryotic cells react to potentially dangerous perturbations of the intracellular or extracellular microenvironment by activating rapid (transcription-independent) mechanisms that attempt to restore homeostasis. If such perturbations persist, cells may still try to cope with stress by activating delayed and robust (transcription-dependent) adaptive systems, or they may actively engage in cellular suicide. This regulated form of cell death can manifest with various morphological, biochemical and immunological correlates, and constitutes an ultimate attempt of stressed cells to maintain organismal homeostasis. Here, we dissect the general organization of adaptive cellular responses to stress, their intimate connection with regulated cell death, and how the latter operates for the preservation of organismal homeostasis. PMID:27048813

  5. The deaths of a cell: how language and metaphor influence the science of cell death.

    PubMed

    Reynolds, Andrew S

    2014-12-01

    Multicellular development and tissue maintenance involve the regular elimination of damaged and healthy cells. The science of this genetically regulated cell death is particularly rich in metaphors: 'programmed cell death' or 'cell suicide' is considered an 'altruistic' act on the part of a cell for the benefit of the organism as a whole. It is also considered a form of 'social control' exerted by the body/organism over its component cells. This paper analyzes the various functions of these metaphors and critical discussion about them within the scientific community. Bodies such as the Nomenclature Committee on Cell Death (NCCD) have been charged with bringing order to the language of cell death to facilitate scientific progress. While the NCCD recommends adopting more objective biochemical terminology to describe the mechanisms of cell death, the metaphors in question retain an important function by highlighting the broader context within which cell death occurs. Scientific metaphors act as conceptual 'tools' which fulfill various roles, from highlighting a phenomenon as of particular interest, situating it in a particular context, or suggesting explanatory causal mechanisms. PMID:25085023

  6. Cell death pathways associated with PDT

    NASA Astrophysics Data System (ADS)

    Kessel, David; Reiners, John J., Jr.

    2006-02-01

    Photodynamic therapy leads to both direct and indirect tumor cell death. The latter also involves the consequences of vascular shut-down and immunologic effects. While these factors are a major factor in tumor eradication, there is usually an element of direct cell killing that can reduce the cell population by as much as 2-3 logs. Necrosis was initially believed to represent the predominant PDT death mechanism. An apoptotic response to PDT was first reported by Oleinick in 1991, using a sensitizer that targets the anti-apoptotic protein Bcl-2. Apoptosis leads to fragmentation of DNA and of cells into apoptotic bodies that are removed by phagocytosis. Inflammatory effects are minimized, and the auto- catalytic elements of the process can amplify the death signal. In this study, we examined consequences of Bcl-2 photodamage by a porphycene sensitizer that targets the ER and causes photodamage to the anti-apoptotic protein Bcl-2. Death patterns after Bcl-2 inactivation by a small-molecular antagonist were also assessed. In addition to apoptosis, we also characterized a hitherto undescribed PDT effect, the initiation of autophagy. Autophagy was initially identified as a cell survival pathway, allowing the recycling of components as nutrients become scarce. We propose that autophagy can also represent both a potential survival pathway after PDT damage to cellular organelles, as well as a cell-death pathway. Recent literature reports indicate that autophagy, as well as apoptosis, can be evoked after down-regulation of Bcl-2, a result consistent with results reported here.

  7. Caspase-1 induced pyroptotic cell death

    PubMed Central

    Miao, Edward A.; Rajan, Jayant V.; Aderem, Alan

    2013-01-01

    Summary Programmed cell death is a necessary part of development and tissue homeostasis enabling the removal of unwanted cells. In the setting of infectious disease, cells that have been commandeered by microbial pathogens become detrimental to the host. When macrophages and dendritic cells are compromised in this way, they can be lysed by pyroptosis, a cell death mechanism that is distinct from apoptosis and oncosis/necrosis. Pyroptosis is triggered by Caspase-1 after its activation by various inflammasomes, and results in lysis of the affected cell. Both pyroptosis and apoptosis are programmed cell death mechanisms, but are dependent on different caspases, unlike oncosis. Similar to oncosis, and unlike apoptosis, pyroptosis results in cellular lysis and release of the cytosolic contents to the extracellular space. This event is predicted to be inherently inflammatory, and additionally coincides with IL-1β and IL-18 secretion. We discuss the role of distinct inflammasomes, including NLRC4, NLRP3 and AIM2, as well as the role of the ASC focus in Caspase-1 signaling. We further review the importance of pyroptosis in vivo as a potent mechanism to clear intracellular pathogens. PMID:21884178

  8. Peroxiredoxins and the Regulation of Cell Death

    PubMed Central

    Hampton, Mark B.; O’Connor, Karina M.

    2016-01-01

    Cell death pathways such as apoptosis can be activated in response to oxidative stress, enabling the disposal of damaged cells. In contrast, controlled intracellular redox events are proposed to be a significant event during apoptosis signaling, regardless of the initiating stimulus. In this scenario oxidants act as second messengers, mediating the post-translational modification of specific regulatory proteins. The exact mechanism of this signaling is unclear, but increased understanding offers the potential to promote or inhibit apoptosis through modulating the redox environment of cells. Peroxiredoxins are thiol peroxidases that remove hydroperoxides, and are also emerging as important players in cellular redox signaling. This review discusses the potential role of peroxiredoxins in the regulation of apoptosis, and also their ability to act as biomarkers of redox changes during the initiation and progression of cell death. PMID:26810076

  9. Proteases in renal cell death: calpains mediate cell death produced by diverse toxicants.

    PubMed

    Schnellmann, R G; Williams, S W

    1998-09-01

    The role of proteases in renal cell death has received limited investigation. Calpains are non-lysosomal cysteine proteases that are Ca+2 activated. Calpain inhibitors that block the active site of calpains (calpain inhibitor 1 and 2) or the Ca+2 binding domain of calpains (PD150606) decreased calpain activity in rabbit renal proximal tubule (RPT) suspensions. The inhibition of calpain activity decreased cell death produced by the diverse toxicants antimycin A (mitochondrial inhibitor), tetrafluroethyl-L-cysteine (nephrotoxic halocarbon), bromohydroquinone (nephro-toxic quinone), t-butylhydroperoxide (model oxidant) and ionomycin (Ca+2 ionophore). In summary, calpains appear to play a common and critical role in cell injury produced by diverse toxicants with different mechanisms of action. The general cysteine protease inhibitor trans-epoxysuccinyl-L-leucylamido (4-guanidino)-butane (E-64) decreased antimycin A- and tetrafluoroethyl-L-cysteine-induced cell death but had no effect on bromohydroquinone- or t-butylhydroperoxide-induced cell death. Serine/cysteine protease inhibitors (antipain, leupeptin) were not cytoprotective to RPT exposed to any of the toxicants. The cytoprotection associated with E-64 correlated with inhibition of lysosomal cathepsins and E-64 was only cytoprotective after some cell death had occurred. Since some cell death occurred prior to the E-64 cytoprotective effect, lysosomal cathepsins may be released from dying cells and subsequently target the remaining viable cells. PMID:9768434

  10. Isolation of a novel paraquat-inducible (pqi) gene regulated by the soxRS locus in Escherichia coli.

    PubMed Central

    Koh, Y S; Roe, J H

    1995-01-01

    We have isolated promoters inducible by paraquat, a superoxide radical-generating agent, from Escherichia coli, using promoter-probing plasmid pJAC4 (Y.S. Koh and J.H. Roe, Korean J. Microbiol. 31:267-273, 1993). One promoter clone pqi-5 (pqi denotes paraquat-inducible gene) was mapped at 21.8 min on the E. coli chromosome by using the Kohara phage library. We constructed an operon fusion of the lacZ gene with the pqi-5 promoter to monitor the expression of the gene in the single-copy state. LacZ expression was induced about 7- to 13-fold by 77 to 780 microM paraquat. Other known superoxide generators such as menadione, phenazine methosulfate, and plumbagin also induced the expression of beta-galactosidase in this fusion strain. On the other hand, no significant induction was observed with treatment with hydrogen peroxide, ethanol, and heat shock. Induction of beta-galactosidase was significantly reduced by introducing a delta sox-8::cat or soxS3::Tn10 mutation into the fusion strain, indicating that pqi-5 is a member of the soxRS regulon. A DNA fragment containing the pqi-5 promoter was cloned and sequenced from the Kohara phage E2E5. We identified two pqi-5 open reading frames (ORFs); ORF-A encodes a predicted protein of 342 amino acids, and ORF-B is truncated at the cloning site. The transcription start site from the pqi-5 promoter was determined by primer extension and S1 nuclease protection analyses. Northern (RNA) and S1 analyses indicated that there are two kinds of pqi-5 transcript; one covers ORF-A only and the other covers ORF-A and possibly also ORF-B. PMID:7751275

  11. Sickle Cell Trait Not Linked to Early Death in Study

    MedlinePlus

    ... html Sickle Cell Trait Not Linked to Early Death in Study However, black soldiers with the gene ... cell gene variant, are at risk of premature death. People with the sickle cell gene variant do ...

  12. Programmed cell death in the plant immune system

    PubMed Central

    Coll, N S; Epple, P; Dangl, J L

    2011-01-01

    Cell death has a central role in innate immune responses in both plants and animals. Besides sharing striking convergences and similarities in the overall evolutionary organization of their innate immune systems, both plants and animals can respond to infection and pathogen recognition with programmed cell death. The fact that plant and animal pathogens have evolved strategies to subvert specific cell death modalities emphasizes the essential role of cell death during immune responses. The hypersensitive response (HR) cell death in plants displays morphological features, molecular architectures and mechanisms reminiscent of different inflammatory cell death types in animals (pyroptosis and necroptosis). In this review, we describe the molecular pathways leading to cell death during innate immune responses. Additionally, we present recently discovered caspase and caspase-like networks regulating cell death that have revealed fascinating analogies between cell death control across both kingdoms. PMID:21475301

  13. Cell Death and Autophagy in TB

    PubMed Central

    Moraco, Andrew H.; Kornfeld, Hardy

    2014-01-01

    Mycobacterium tuberculosis has succeeded in infecting one third of the human race though inhibition or evasion of innate and adaptive immunity. The pathogen is a facultative intracellular parasite that uses the niche provided by mononuclear phagocytes for its advantage. Complex interactions determine whether the bacillus will or will not be delivered to acidified lysosomes, whether the host phagocyte will survive infection or die, and whether the timing and mode of cell death works to the advantage of the host or the pathogen. Here we discuss cell death and autophagy in TB. These fundamental processes of cell biology feature in all aspects of TB pathogenesis and may be exploited to the treatment or prevention of TB disease. PMID:25453227

  14. [Cell death in malignant tumors. Relevance of cell death regulation for metastasis].

    PubMed

    Roth, W

    2015-11-01

    Defects in the regulation of cell death are important causes for both the development and therapy resistance of malignant tumors. Several distinct, molecularly defined types of cell death are known, such as apoptosis, anoikis, and necroptosis. Moreover, the specific triggering of cell death plays an important role in the prevention of metastasis. The results of recent studies have shown that various types of cell death are pivotal at different steps of the metastasis cascade, in order to prevent cellular detachment, migration, invasion, intravasation, extravasation and the establishment of micrometastasis and macrometastasis. At the subcellular level, numerous links exist between cell death regulation and metastasis, specifically regarding signaling pathways and individual proteins with dual or multiple functions. As an example, the decoy receptor 3 protein (DcR3) functions both as an anti-apoptotic protein and as a direct promotor of invasion and migration of tumor cells. In summary, the specific triggering of cell death plays a pivotal role for the prevention of metastasis. On the other hand, the stepwise process of metastasis represents a mechanism of selection resulting in established metastases with a multiresistant phenotype which corresponds to the clinical observation that many metastasized cancers are therapy resistant. In the future, innovative diagnostic tests to individually predict the resistance pattern and possibilities to overcome resistance are urgently needed. PMID:26400565

  15. Programmed cell death during quinoa perisperm development

    PubMed Central

    Maldonado, Sara

    2013-01-01

    At seed maturity, quinoa (Chenopodium quinoa Willd.) perisperm consists of uniform, non-living, thin-walled cells full of starch grains. The objective of the present study was to study quinoa perisperm development and describe the programme of cell death that affects the entire tissue. A number of parameters typically measured during programmed cell death (PCD), such as cellular morphological changes in nuclei and cytoplasm, endoreduplication, DNA fragmentation, and the participation of nucleases and caspase-like proteases in nucleus dismantling, were evaluated; morphological changes in cytoplasm included subcellular aspects related to starch accumulation. This study proved that, following fertilization, the perisperm of quinoa simultaneously accumulates storage reserves and degenerates, both processes mediated by a programme of developmentally controlled cell death. The novel findings regarding perisperm development provide a starting point for further research in the Amaranthaceae genera, such as comparing seeds with and without perisperm, and specifying phylogeny and evolution within this taxon. Wherever possible and appropriate, differences between quinoa perisperm and grass starchy endosperm—a morphologically and functionally similar, although genetically different tissue—were highlighted and discussed. PMID:23833197

  16. Role of polyphenols in cell death control.

    PubMed

    Giovannini, Claudio; Masella, Roberta

    2012-05-01

    Dietary consumption of fruit, vegetables, fish, and olive oil has been demonstrated to exert beneficial effects on human health. This finding may be due to the high content of antioxidant compounds including polyphenols. Current evidence strongly supports a contribution of polyphenols to the prevention of several chronic degenerative diseases such as cancer, atherosclerosis and cardiovascular diseases, central nervous system disorders, as well as aging. Apoptosis is a genetically controlled and evolutionarily conserved form of cell death of critical importance for the maintenance of tissue homeostasis in the adult organism. The malfunction of the death machinery may play a primary role in various pathologic processes, leading to proliferative or degenerative diseases. Polyphenols can interact with specific steps and/or proteins regulating the apoptotic process in different ways depending on their concentration, the cell system, the type or stage of the pathological process. Because of their ability to modulate cell death, polyphenols have been proposed as chemopreventive and therapeutic agents. This paper reviews and discusses the last 3-year findings related to the principal molecular mechanisms involved in the control of the balance between apoptosis and cell proliferation exerted by polyphenols. PMID:22584012

  17. [Progress on pathogenesis and treatment of paraquat-induced pulmonary fibrosis].

    PubMed

    Shao, Xue; Chen, Jiang-Hua

    2014-11-01

    Paraquat (PQ) is a highly effective herbicide with contact toxicity. PQ mainly accumulates in the lungs after absorption into the blood circulation. The respiratory function failure caused by PQ-induced lung injury, especially the irreversible pulmonary fibrosis in late phase, is the leading cause of death in patients with PQ poisoning. The mechanism of PQ poisoning is still unclear. Now it is speculated that oxidative stress and inflammation injury are the main pathogenic mechanisms, and abnormal gene expression, mitochondrial damage, loss of pulmonary surfactant, cytokine network and unbalanced matrix metalloproteinases/tissue inhibitors may be also involved in the pathogenesis. In addition to reducing poison absorption and increasing its removal, the current clinical treatment is mainly composed of antioxidant and anti-immune response, but has poor therapeutic effects. Although many novel methods of treatment have been proposed, most of them are still in the experimental stage. It is a hot spot to clarify the mechanism of PQ poisoning and to seek safe and effective treatment of pulmonary fibrosis. This article reviews the research progress on pathogenesis and treatment of PQ-induced pulmonary fibrosis. PMID:25644573

  18. Regulated cell death in diagnostic histopathology.

    PubMed

    Skenderi, Faruk; Vranic, Semir; Damjanov, Ivan

    2015-01-01

    Regulated cell death (RCD) is a controlled cellular process, essential for normal development, tissue integrity and homeostasis, and its dysregulation has been implicated in the pathogenesis of various conditions including developmental and immunological disorders, neurodegenerative diseases, and cancer. In this review, we briefly discuss the historical perspective and conceptual development of RCD, we overview recent classifications and some of the key players in RCD; finally we focus on current applications of RCD in diagnostic histopathology. PMID:26009238

  19. Cell death and deubiquitinases: perspectives in cancer.

    PubMed

    Bhattacharya, Seemana; Ghosh, Mrinal Kanti

    2014-01-01

    The process of cell death has important physiological implications. At the organism level it is mostly involved in maintenance of tissue homeostasis. At the cellular level, the strategies of cell death may be categorized as either suicide or sabotage. The mere fact that many of these processes are programmed and that these are often deregulated in pathological conditions is seed to thought. The various players that are involved in these pathways are highly regulated. One of the modes of regulation is via post-translational modifications such as ubiquitination and deubiquitination. In this review, we have first dealt with the different modes and pathways involved in cell death and then we have focused on the regulation of several proteins in these signaling cascades by the different deubiquitinating enzymes, in the perspective of cancer. The study of deubiquitinases is currently in a rather nascent stage with limited knowledge both in vitro and in vivo, but the emerging roles of the deubiquitinases in various processes and their specificity have implicated them as potential targets from the therapeutic point of view. This review throws light on another aspect of cancer therapeutics by targeting the deubiquitinating enzymes. PMID:25121098

  20. Cell Death and Deubiquitinases: Perspectives in Cancer

    PubMed Central

    Bhattacharya, Seemana

    2014-01-01

    The process of cell death has important physiological implications. At the organism level it is mostly involved in maintenance of tissue homeostasis. At the cellular level, the strategies of cell death may be categorized as either suicide or sabotage. The mere fact that many of these processes are programmed and that these are often deregulated in pathological conditions is seed to thought. The various players that are involved in these pathways are highly regulated. One of the modes of regulation is via post-translational modifications such as ubiquitination and deubiquitination. In this review, we have first dealt with the different modes and pathways involved in cell death and then we have focused on the regulation of several proteins in these signaling cascades by the different deubiquitinating enzymes, in the perspective of cancer. The study of deubiquitinases is currently in a rather nascent stage with limited knowledge both in vitro and in vivo, but the emerging roles of the deubiquitinases in various processes and their specificity have implicated them as potential targets from the therapeutic point of view. This review throws light on another aspect of cancer therapeutics by targeting the deubiquitinating enzymes. PMID:25121098

  1. Programmed Cell Death of Dendritic Cells in Immune Regulation

    PubMed Central

    Chen, Min; Wang, Jin

    2010-01-01

    Summary Programmed cell death is essential for the maintenance of lymphocyte homeostasis and immune tolerance. Dendritic cells (DCs), the most efficient antigen presenting cells, represent a small cell population in the immune system. However, DCs play major roles in the regulation of both innate and adaptive immune responses. Programmed cell death in DCs is essential for regulating DC homeostasis and consequently, the scope of immune responses. Interestingly, different DC subsets show varied turnover rates in vivo. The conventional DCs are relatively short-lived in most lymphoid organs, while plasmacytoid DCs are long-lived cells. Mitochondrion-dependent programmed cell death plays an important role in regulating spontaneous DC turnover. Antigen-specific T cells are also capable of killing DCs, thereby providing a mechanism for negative feedback regulation of immune responses. It has been shown that a surplus of DCs due to defects in programmed cell death leads to overactivation of lymphocytes and the onset of autoimmunity. Studying programmed cell death in DCs will shed light on the roles for DC turnover in the regulation of the duration and magnitude of immune responses in vivo, and in the maintenance of immune tolerance. PMID:20636805

  2. Lysyl oxidase promotes epithelial-to-mesenchymal transition during paraquat-induced pulmonary fibrosis.

    PubMed

    Wang, Jinfeng; Zhu, Yong; Tan, Jiuting; Meng, Xiaoxiao; Xie, Hui; Wang, Ruilan

    2016-02-01

    Lysyl oxidase (LOX) is a copper-dependent amine oxidase that plays a critical role in pulmonary fibrosis. Our previous study demonstrated that epithelial-to-mesenchymal transition (EMT) was strongly associated with paraquat (PQ) induced pulmonary fibrosis. This present study was aimed to evaluate the potential involvement of LOX on EMT in the process of pulmonary fibrosis induced by PQ. We established an in vivo rat model and an in vitro cell model induced by PQ treatment and found that LOX protein expression was significantly up-regulated and collagen deposition was enhanced in rats. The EMT process was strongly found in A549 and RLE-6TN cells after PQ exposure. After inactivating LOX with an inhibitor, pulmonary fibrosis was significantly reduced and EMT was also suppressed. Additionally, small interfering RNA (siRNA) targeting LOX was used to silence LOX expression to observe EMT in A549 cells. As a result, LOX could promote the progress of EMT, and inactivating LOX alleviated the EMT process in PQ-induced pulmonary fibrosis and mesenchymal-to-epithelial transition (MET) occurred after inactivating LOX in vitro and in vivo. In conclusion, LOX could promote the progress of EMT and inactivating LOX alleviated EMT in PQ-induced pulmonary fibrosis. Therefore, LOX could potentially be a new candidate therapeutic target for pulmonary fibrosis induced by PQ by regulating the balance between EMT and MET. PMID:26670953

  3. Current and Emerging Biomarkers of Cell Death in Human Disease

    PubMed Central

    Li, Kongning; Wu, Deng; Chen, Xi; Zhang, Ting; Zhang, Lu; Yi, Ying; Miao, Zhengqiang; Jin, Nana; Bi, Xiaoman; Wang, Hongwei; Wang, Dong

    2014-01-01

    Cell death is a critical biological process, serving many important functions within multicellular organisms. Aberrations in cell death can contribute to the pathology of human diseases. Significant progress made in the research area enormously speeds up our understanding of the biochemical and molecular mechanisms of cell death. According to the distinct morphological and biochemical characteristics, cell death can be triggered by extrinsic or intrinsic apoptosis, regulated necrosis, autophagic cell death, and mitotic catastrophe. Nevertheless, the realization that all of these efforts seek to pursue an effective treatment and cure for the disease has spurred a significant interest in the development of promising biomarkers of cell death to early diagnose disease and accurately predict disease progression and outcome. In this review, we summarize recent knowledge about cell death, survey current and emerging biomarkers of cell death, and discuss the relationship with human diseases. PMID:24949464

  4. Characterization of Paraquat-Induced miRNA Profiling Response in hNPCs Undergoing Proliferation

    PubMed Central

    Huang, Min; Lou, Dan; Cai, Qian; Chang, Xiuli; Wang, Xinjin; Zhou, Zhijun

    2014-01-01

    Aberration during the development of the central nervous system (CNS) due to environmental factors underlies a variety of adverse developmental outcomes. Paraquat (PQ) is a widely studied neurotoxicant that perturbs the normal structure/function of adult CNS. Yet, the impacts of PQ exposure on the developing CNS remain unclear. miRNAs represent a class of small non-coding RNA molecules involved in the regulation of neural development. Thus in the present study, we analyzed the impacts of PQ on the miRNome of human neural progenitor cells (hNPCs) during proliferation by using the Exiqon miRCURY™ LNA Array. A total of 66 miRNAs were identified as differentially expressed in proliferating hNPCs upon PQ treatment. miRTarBase prediction identified 1465 mRNAs, including several genes (e.g., nestin, sox1, ngn1) previously proved to be associated with the neural proliferation and differentiation, as target genes of PQ-induced differentially expressed miRNAs. The database for annotation, visualization and integrated discovery (DAVID) bioinformatics analysis showed that target genes were enriched in regulation of cell proliferation and differentiation, cell cycle and apoptosis as well as tumor protein 53 (p53), Wnt, Notch and mitogen-activated protein kinases (MAPK) signaling pathways (p < 0.001). These findings were confirmed by real-time RT-PCR. Based on our results we conclude that PQ-induced impacts on the miRNA profiling of hNPCs undergoing proliferation may underlie the developmental neurotoxicity of PQ. PMID:25314302

  5. Cellular functions of programmed cell death 5.

    PubMed

    Li, Ge; Ma, Dalong; Chen, Yingyu

    2016-04-01

    Programmed cell death 5 (PDCD5) was originally identified as an apoptosis-accelerating protein that is widely expressed and has been well conserved during the process of evolution. PDCD5 has complex biological functions, including programmed cell death and immune regulation. It can accelerate apoptosis in different type of cells in response to different stimuli. During this process, PDCD5 rapidly translocates from the cytoplasm to the nucleus. PDCD5 regulates the activities of TIP60, HDAC3, MDM2 and TP53 transcription factors. These proteins form part of a signaling network that is disrupted in most, if not all, cancer cells. Recent evidence suggests that PDCD5 participates in immune regulation by promoting regulatory T cell function via the PDCD5-TIP60-FOXP3 pathway. The stability and expression of PDCD5 are finely regulated by other molecules, such as NF-κB p65, OTUD5, YAF2 and DNAJB1. PDCD5 is phosphorylated by CK2 at Ser119, which is required for nuclear translocation in response to genotoxic stress. In this review, we describe what is known about PDCD5 and its cellular functions. PMID:26775586

  6. Cell Death Control by Matrix Metalloproteinases.

    PubMed

    Zimmermann, Dirk; Gomez-Barrera, Juan A; Pasule, Christian; Brack-Frick, Ursula B; Sieferer, Elke; Nicholson, Tim M; Pfannstiel, Jens; Stintzi, Annick; Schaller, Andreas

    2016-06-01

    In contrast to mammalian matrix metalloproteinases (MMPs) that play important roles in the remodeling of the extracellular matrix in animals, the proteases responsible for dynamic modifications of the plant cell wall are largely unknown. A possible involvement of MMPs was addressed by cloning and functional characterization of Sl2-MMP and Sl3-MMP from tomato (Solanum lycopersicum). The two tomato MMPs were found to resemble mammalian homologs with respect to gelatinolytic activity, substrate preference for hydrophobic amino acids on both sides of the scissile bond, and catalytic properties. In transgenic tomato seedlings silenced for Sl2/3-MMP expression, necrotic lesions were observed at the base of the hypocotyl. Cell death initiated in the epidermis and proceeded to include outer cortical cell layers. In later developmental stages, necrosis spread, covering the entire stem and extending into the leaves of MMP-silenced plants. The subtilisin-like protease P69B was identified as a substrate of Sl2- and Sl3-MMP. P69B was shown to colocalize with Sl-MMPs in the apoplast of the tomato hypocotyl, it exhibited increased stability in transgenic plants silenced for Sl-MMP activity, and it was cleaved and inactivated by Sl-MMPs in vitro. The induction of cell death in Sl2/3-MMP-silenced plants depended on P69B, indicating that Sl2- and Sl3-MMP act upstream of P69B in an extracellular proteolytic cascade that contributes to the regulation of cell death in tomato. PMID:27208293

  7. Autophagic cell death: Loch Ness monster or endangered species?

    PubMed

    Shen, Han-Ming; Codogno, Patrice

    2011-05-01

    The concept of autophagic cell death was first established based on observations of increased autophagic markers in dying cells. The major limitation of such a morphology-based definition of autophagic cell death is that it fails to establish the functional role of autophagy in the cell death process, and thus contributes to the confusion in the literature regarding the role of autophagy in cell death and cell survival. Here we propose to define autophagic cell death as a modality of non-apoptotic or necrotic programmed cell death in which autophagy serves as a cell death mechanism, upon meeting the following set of criteria: (i) cell death occurs without the involvement of apoptosis; (ii) there is an increase of autophagic flux, and not just an increase of the autophagic markers, in the dying cells; and (iii) suppression of autophagy via both pharmacological inhibitors and genetic approaches is able to rescue or prevent cell death. In light of this new definition, we will discuss some of the common problems and difficulties in the study of autophagic cell death and also revisit some well-reported cases of autophagic cell death, aiming to achieve a better understanding of whether autophagy is a real killer, an accomplice or just an innocent bystander in the course of cell death. At present, the physiological relevance of autophagic cell death is mainly observed in lower eukaryotes and invertebrates such as Dictyostelium discoideum and Drosophila melanogaster. We believe that such a clear definition of autophagic cell death will help us study and understand the physiological or pathological relevance of autophagic cell death in mammals. PMID:21150268

  8. Comparison of Types of Cell Death: Apoptosis and Necrosis.

    ERIC Educational Resources Information Center

    Manning, Francis; Zuzel, Katherine

    2003-01-01

    Cell death is an essential factor in many biological processes including development. Discusses two types of cell death: (1) necrosis (induced by sodium azide); and (2) apoptosis (induced by sodium chromate). Illustrates key features that differ between these two types of cells death including loss of membrane integrity and internucleosomal DNA…

  9. ACCELERATED CELL DEATH2 suppresses mitochondrial oxidative bursts and modulates cell death in Arabidopsis

    PubMed Central

    Pattanayak, Gopal K.; Venkataramani, Sujatha; Hortensteiner, Stefan; Kunz, Lukas; Christ, Bastien; Moulin, Michael; Smith, Alison G.; Okamoto, Yukihiro; Tamiaki, Hitoshi; Sugishima, Masakazu; Greenberg, Jean T.

    2012-01-01

    SUMMARY The Arabidopsis ACCELERATED CELL DEATH 2 (ACD2) protein protects cells from programmed cell death (PCD) caused by endogenous porphyrin-related molecules like red chlorophyll catabolite or exogenous protoporphyrin IX. We previously found that during bacterial infection, ACD2, a chlorophyll breakdown enzyme, localizes to both chloroplasts and mitochondria in leaves. Additionally, acd2 cells show mitochondrial dysfunctions. In plants with acd2 and ACD2+ sectors, ACD2 functions cell autonomously, implicating a pro-death ACD2 substrate as cell non-autonomous in promoting spreading PCD. ACD2 targeted solely to mitochondria can reduce the accumulation of an ACD2 substrate that originates in chloroplasts, indicating that ACD2 substrate molecules are likely mobile within cells. Two different light-dependent reactive oxygen bursts in mitochondria play prominent and causal roles in the acd2 PCD phenotype. Finally, ACD2 can complement acd2 when targeted to mitochondria or chloroplasts, respectively, as long as it is catalytically active; the ability to bind substrate is not sufficient for ACD2 to function in vitro or in vivo. Together the data suggest that ACD2 localizes dynamically during infection to protect cells from pro-death mobile substrate molecules, some of which may originate in chloroplasts, but have major effects on mitochondria. PMID:21988537

  10. The role of free radicals in paraquat-induced corneal lesions.

    PubMed

    Nordquist, R E; Nguyen, H; Poyer, J L; Carubelli, R

    1995-07-01

    Paraquat is a synthetic bipyridylium salt widely used as herbicide and defoliant. Enzyme-catalyzed redoxcycling of paraquat generates oxygen radicals. The toxic, even lethal, effects of paraquat are due to free radical-mediated tissue injury. Ocular lesions, sometimes quite severe, have been observed following accidental splashing of paraquat solutions onto the eyes. These studies were designed to document the generation of paraquat free radicals in corneal tissue, and to describe the histological nature of the corneal injuries in experimental animals (rabbits and monkeys). The EPR spectrum of rabbit corneas, 30 min. after intrastromal injection of paraquat, showed the signal of the free radical of paraquat. Ultrastructural studies of corneas 8 days after intrastromal injections (100 microliters) of paraquat solutions showed that the initial lesions occur at the epithelium/basement membrane interface. In rabbit cornea, dose dependent lesions were observed, i.e. whereas 50 mM paraquat caused only minimal damage to the epithelial basement membrane, 75 mM caused complete dissolution to the basement membrane with some damage to stromal collagen, and loss of epithelium with stromal ulceration and severe inflammatory response were observed with 150 mM paraquat. Monkey corneas were less susceptible than those of rabbits to the effects of paraquat. No lesions were observed following intrastromal injections of 50 mM or 75 mM paraquat. With higher concentrations of paraquat (100 mM and 150 mM) the primary injuries were to the proximal and lateral plasma membranes of basal epithelial cells; basement membrane alterations were detected only adjacent to areas of significant plasma membrane damage. The underlying Bowman's membrane and stroma were not affected. Anatomical differences between the corneas of rabbit and monkeys as well as possible biochemical differences may account for the species differences observed. PMID:7647920

  11. Inhibition of caspases prevents ototoxic and ongoing hair cell death

    NASA Technical Reports Server (NTRS)

    Matsui, Jonathan I.; Ogilvie, Judith M.; Warchol, Mark E.

    2002-01-01

    Sensory hair cells die after acoustic trauma or ototoxic insults, but the signal transduction pathways that mediate hair cell death are not known. Here we identify several important signaling events that regulate the death of vestibular hair cells. Chick utricles were cultured in media supplemented with the ototoxic antibiotic neomycin and selected pharmacological agents that influence signaling molecules in cell death pathways. Hair cells that were treated with neomycin exhibited classically defined apoptotic morphologies such as condensed nuclei and fragmented DNA. Inhibition of protein synthesis (via treatment with cycloheximide) increased hair cell survival after treatment with neomycin, suggesting that hair cell death requires de novo protein synthesis. Finally, the inhibition of caspases promoted hair cell survival after neomycin treatment. Sensory hair cells in avian vestibular organs also undergo continual cell death and replacement throughout mature life. It is unclear whether the loss of hair cells stimulates the proliferation of supporting cells or whether the production of new cells triggers the death of hair cells. We examined the effects of caspase inhibition on spontaneous hair cell death in the chick utricle. Caspase inhibitors reduced the amount of ongoing hair cell death and ongoing supporting cell proliferation in a dose-dependent manner. In isolated sensory epithelia, however, caspase inhibitors did not affect supporting cell proliferation directly. Our data indicate that ongoing hair cell death stimulates supporting cell proliferation in the mature utricle.

  12. Apoptosis, oncosis, and necrosis. An overview of cell death.

    PubMed Central

    Majno, G.; Joris, I.

    1995-01-01

    The historical development of the cell death concept is reviewed, with special attention to the origin of the terms necrosis, coagulation necrosis, autolysis, physiological cell death, programmed cell death, chromatolysis (the first name of apoptosis in 1914), karyorhexis, karyolysis, and cell suicide, of which there are three forms: by lysosomes, by free radicals, and by a genetic mechanism (apoptosis). Some of the typical features of apoptosis are discussed, such as budding (as opposed to blebbing and zeiosis) and the inflammatory response. For cell death not by apoptosis the most satisfactory term is accidental cell death. Necrosis is commonly used but it is not appropriate, because it does not indicate a form of cell death but refers to changes secondary to cell death by any mechanism, including apoptosis. Abundant data are available on one form of accidental cell death, namely ischemic cell death, which can be considered an entity of its own, caused by failure of the ionic pumps of the plasma membrane. Because ischemic cell death (in known models) is accompanied by swelling, the name oncosis is proposed for this condition. The term oncosis (derived from ónkos, meaning swelling) was proposed in 1910 by von Reckling-hausen precisely to mean cell death with swelling. Oncosis leads to necrosis with karyolysis and stands in contrast to apoptosis, which leads to necrosis with karyorhexis and cell shrinkage. Images Figure 1 Figure 2 Figure 3 Figure 5 Figure 6 Figure 7 Figure 8 PMID:7856735

  13. Oncogenes in Cell Survival and Cell Death

    PubMed Central

    Shortt, Jake; Johnstone, Ricky W.

    2012-01-01

    The transforming effects of proto-oncogenes such as MYC that mediate unrestrained cell proliferation are countered by “intrinsic tumor suppressor mechanisms” that most often trigger apoptosis. Therefore, cooperating genetic or epigenetic effects to suppress apoptosis (e.g., overexpression of BCL2) are required to enable the dual transforming processes of unbridled cell proliferation and robust suppression of apoptosis. Certain oncogenes such as BCR-ABL are capable of concomitantly mediating the inhibition of apoptosis and driving cell proliferation and therefore are less reliant on cooperating lesions for transformation. Accordingly, direct targeting of BCR-ABL through agents such as imatinib have profound antitumor effects. Other oncoproteins such as MYC rely on the anti-apoptotic effects of cooperating oncoproteins such as BCL2 to facilitate tumorigenesis. In these circumstances, where the primary oncogenic driver (e.g., MYC) cannot yet be therapeutically targeted, inhibition of the activity of the cooperating antiapoptotic protein (e.g., BCL2) can be exploited for therapeutic benefit. PMID:23209150

  14. Melting Behaviour of Cell Death Lipids

    NASA Astrophysics Data System (ADS)

    Leung, Sherry; Sot, Jesus; Goni, Felix; Thewalt, Jenifer

    2009-05-01

    Sphingomyelin is a major lipid constituent of mammalian cell plasma membranes. It is converted into ceramide during programmed cell death. It is hypothesized that this conversion induces a structural change in membranes that is responsible for downstream signaling. To characterize these structural changes, deuterium nuclear magnetic resonance spectroscopy is used to create a concentration-temperature phase diagram of palmitoyl sphingomyelin:ceramide multilamellar vesicles in excess water between 0-40 mol% ceramide and 25-80^oC. The two lipids are fully miscible at high temperatures and at 40 mol% ceramide. A variety of solid-liquid coexistence phase behavior is observed at lower concentrations. With increasing ceramide content, a gel phase is observed at progressively higher temperatures, implying that at physiological temperature, ceramide may increase the gel phase propensity of cell membranes.

  15. Programmed Cell Death in Unicellular Phytoplankton.

    PubMed

    Bidle, Kay D

    2016-07-11

    Unicellular, planktonic, prokaryotic and eukaryotic photoautotrophs (phytoplankton) have an ancient evolutionary history on Earth during which time they have played key roles in the regulation of marine food webs, biogeochemical cycles, and Earth's climate. Since they represent the basis of aquatic ecosystems, the manner in which phytoplankton die critically determines the flow and fate of photosynthetically fixed organic matter (and associated elements), ultimately constraining nutrient flow. Programmed cell death (PCD) and associated pathway genes, which are triggered by a variety of abiotic (nutrient, light, osmotic) and biotic (virus infection, allelopathy) environmental stresses, have an integral grip on cell fate, and have shaped the ecological success and evolutionary trajectory of diverse phytoplankton lineages. A combination of physiological, biochemical, and genetic techniques in model algal systems has demonstrated a conserved molecular and mechanistic framework of stress surveillance, signaling, and death activation pathways, involving collective and coordinated participation of organelles, redox enzymes, metabolites, and caspase-like proteases. This mechanistic understanding has provided insight into the integration of sensing and transduction of stress signals into cellular responses, and the mechanistic interfaces between PCD, cell stress and virus infection pathways. It has also provided insight into the evolution of PCD in unicellular photoautotrophs, the impact of PCD on the fate of natural phytoplankton assemblages and its role in aquatic biogeochemical cycles. PMID:27404255

  16. Macrophage cell death upon intracellular bacterial infection

    PubMed Central

    Lai, Xin-He; Xu, Yunsheng; Chen, Xiao-Ming; Ren, Yi

    2015-01-01

    Macrophage-pathogen interaction is a complex process and the outcome of this tag-of-war for both sides is to live or die. Without attempting to be comprehensive, this review will discuss the complexity and significance of the interaction outcomes between macrophages and some facultative intracellular bacterial pathogens as exemplified by Francisella, Salmonella, Shigella and Yersinia. Upon bacterial infection, macrophages can die by a variety of ways, such as apoptosis, autophagic cell death, necrosis, necroptosis, oncosis, pyronecrosis, pyroptosis etc, which is the focus of this review. PMID:26690967

  17. Caspase Functions in Cell Death and Disease

    PubMed Central

    McIlwain, David R.; Berger, Thorsten; Mak, Tak W.

    2013-01-01

    Caspases are a family of endoproteases that provide critical links in cell regulatory networks controlling inflammation and cell death. The activation of these enzymes is tightly controlled by their production as inactive zymogens that gain catalytic activity following signaling events promoting their aggregation into dimers or macromolecular complexes. Activation of apoptotic caspases results in inactivation or activation of substrates, and the generation of a cascade of signaling events permitting the controlled demolition of cellular components. Activation of inflammatory caspases results in the production of active proinflammatory cytokines and the promotion of innate immune responses to various internal and external insults. Dysregulation of caspases underlies human diseases including cancer and inflammatory disorders, and major efforts to design better therapies for these diseases seek to understand how these enzymes work and how they can be controlled. PMID:23545416

  18. Expanding roles of programmed cell death in mammalian neurodevelopment.

    PubMed

    De Zio, Daniela; Giunta, Luigi; Corvaro, Marco; Ferraro, Elisabetta; Cecconi, Francesco

    2005-04-01

    Programmed cell death is an orchestrated form of cell death in which cells are actively involved in their own demise. During neural development in mammals, many progenitor cells, immature cells or differentiated cells undergo the most clearly characterized type of cell death, apoptosis. Several pathways of apoptosis have been linked to neural development, but according to the numerous and striking phenotypes observed when apoptotic genes are inactivated, the mitochondrial death-route is the most important pathway in this context. Here, we discuss the relative importance of pro-growth/pro-death factors in the control of neural tissue development. We also discuss the impact of studying programmed cell death in development in order to better understand the basis of several human diseases and embryonic defects of the nervous system. PMID:15797838

  19. The antidote effect of quinone oxidoreductase 2 inhibitor against paraquat-induced toxicity in vitro and in vivo

    PubMed Central

    Janda, Elzbieta; Parafati, Maddalena; Aprigliano, Serafina; Carresi, Cristina; Visalli, Valeria; Sacco, Iolanda; Ventrice, Domenica; Mega, Tiziana; Vadalá, Nuria; Rinaldi, Stefano; Musolino, Vincenzo; Palma, Ernesto; Gratteri, Santo; Rotiroti, Domenicantonio; Mollace, Vincenzo

    2013-01-01

    BACKGROUND AND PURPOSE The mechanisms of paraquat (PQ)-induced toxicity are poorly understood and PQ poisoning is often fatal due to a lack of effective antidotes. In this study we report the effects of N-[2-(2-methoxy-6H-dipyrido{2,3-a:3,2-e}pyrrolizin-11-yl)ethyl]-2-furamide (NMDPEF), a melatonin-related inhibitor of quinone oxidoreductase2 (QR2) on the toxicity of PQ in vitro & in vivo. EXPERIMENTAL APPROACH Prevention of PQ-induced toxicity was tested in different cells, including primary pneumocytes and astroglial U373 cells. Cell death and reactive oxygen species (ROS) were analysed by flow cytometry and fluorescent probes. QR2 silencing was achieved by lentiviral shRNAs. PQ (30 mg·kg−1) and NMDPEF were administered i.p. to Wistar rats and animals were monitored for 28 days. PQ toxicity in the substantia nigra (SN) was tested by a localized microinfusion and electrocorticography. QR2 activity was measured by fluorimetry of N-benzyldihydronicotinamide oxidation. KEY RESULTS NMDPEF potently antagonized non-apoptotic PQ-induced cell death, ROS generation and inhibited cellular QR2 activity. In contrast, the cytoprotective effect of melatonin and apocynin was limited and transient compared with NMDPEF. Silencing of QR2 attenuated PQ-induced cell death and reduced the efficacy of NMDPEF. Significantly, NMDPEF (4.5 mg·kg−1) potently antagonized PQ-induced systemic toxicity and animal mortality. Microinfusion of NMDPEF into SN prevented severe behavioural and electrocortical effects of PQ which correlated with inhibition of malondialdehyde accumulation in cells and tissues. CONCLUSIONS AND IMPLICATIONS NMDPEF protected against PQ-induced toxicity in vitro and in vivo, suggesting a key role for QR2 in the regulation of oxidative stress. LINKED ARTICLE This article is commented on by Baltazar et al., pp. 44–45 of this issue. To view this commentary visit http://dx.doi.org/10.1111/j.1476-5381.2012.02017.x PMID:22289031

  20. Modes of Retinal Cell Death in Diabetic Retinopathy.

    PubMed

    Feenstra, Derrick J; Yego, E Chepchumba; Mohr, Susanne

    2013-10-01

    Cell death seems to be a prominent feature in the progression of diabetic retinopathy. Several retinal cell types have been identified to undergo cell death in a diabetic environment. Most emphasis has been directed towards identifying apoptosis in the diabetic retina. However, new research has established that there are multiple forms of cell death. This review discusses the different modes of cell death and attempts to classify cell death of retinal cells known to die in diabetic retinopathy. Special emphasis is given to apoptosis, necrosis, autophagic cell death, and pyroptosis. It seems that different retinal cell types are dying by diverse types of cell death. Whereas endothelial cells predominantly undergo apoptosis, pericytes might die by apoptosis as well as necrosis. On the other hand, Müller cells are suggested to die by a pyroptotic mechanism. Diabetes leads to significant Müller cell loss at 7 months duration of diabetes in retinas of diabetic mice compared to non-diabetic, which is prevented by the inhibition of the caspase-1/IL-1β (interleukin-1beta) pathway using the IL-1 receptor knockout mouse. Since pyroptosis is characterized by the activation of the caspase-1/IL-1β pathway subsequently leading to cell death, Müller cells seem to be a prime candidate for this form of inflammation-driven cell death. Considering that diabetic retinopathy is now discussed to potentially be a chronic inflammatory disease, pyroptotic cell death might play an important role in disease progression. Understanding mechanisms of cell death will lead to a more targeted approach in the development of new therapies to treat diabetic retinopathy. PMID:24672740

  1. Cell block eleven, looking from the "Death Row" exercise yard, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Cell block eleven, looking from the "Death Row" exercise yard, facing north (note cell block fifteen to the right and cell block fourteen in the distance_ - Eastern State Penitentiary, 2125 Fairmount Avenue, Philadelphia, Philadelphia County, PA

  2. Programmed cell death for defense against anomaly and tumor formation

    SciTech Connect

    Kondo, Sohei; Norimura, Toshiyuki; Nomura, Taisei

    1995-12-31

    Cell death after exposure to low-level radiation is often considered evidence that radiation is poisonous, however small the dose. Evidence has been accumulating to support the notion that cell death after low-level exposure to radiation results from activation of suicidal genes {open_quote}programmed cell death{close_quote} or {open_quote}apoptosis{close_quote} - for the health of the whole body. This paper gives experimental evidence that embryos of fruit flies and mouse fetuses have potent defense mechanisms against teratogenic or tumorigenic injury caused by radiation and carcinogens, which function through programmed cell death.

  3. Cell death sensitization of leukemia cells by opioid receptor activation

    PubMed Central

    Friesen, Claudia; Roscher, Mareike; Hormann, Inis; Fichtner, Iduna; Alt, Andreas; Hilger, Ralf A.; Debatin, Klaus-Michael; Miltner, Erich

    2013-01-01

    Cyclic AMP (cAMP) regulates a number of cellular processes and modulates cell death induction. cAMP levels are altered upon stimulation of specific G-protein-coupled receptors inhibiting or activating adenylyl cyclases. Opioid receptor stimulation can activate inhibitory Gi-proteins which in turn block adenylyl cyclase activity reducing cAMP. Opioids such as D,L-methadone induce cell death in leukemia cells. However, the mechanism how opioids trigger apoptosis and activate caspases in leukemia cells is not understood. In this study, we demonstrate that downregulation of cAMP induced by opioid receptor activation using the opioid D,L-methadone kills and sensitizes leukemia cells for doxorubicin treatment. Enhancing cAMP levels by blocking opioid-receptor signaling strongly reduced D,L-methadone-induced apoptosis, caspase activation and doxorubicin-sensitivity. Induction of cell death in leukemia cells by activation of opioid receptors using the opioid D,L-methadone depends on critical levels of opioid receptor expression on the cell surface. Doxorubicin increased opioid receptor expression in leukemia cells. In addition, the opioid D,L-methadone increased doxorubicin uptake and decreased doxorubicin efflux in leukemia cells, suggesting that the opioid D,L-methadone as well as doxorubicin mutually increase their cytotoxic potential. Furthermore, we found that opioid receptor activation using D,L-methadone alone or in addition to doxorubicin inhibits tumor growth significantly in vivo. These results demonstrate that opioid receptor activation via triggering the downregulation of cAMP induces apoptosis, activates caspases and sensitizes leukemia cells for doxorubicin treatment. Hence, opioid receptor activation seems to be a promising strategy to improve anticancer therapies. PMID:23633472

  4. Arabidopsis ACCELERATED CELL DEATH2 Modulates Programmed Cell DeathW⃞

    PubMed Central

    Yao, Nan; Greenberg, Jean T.

    2006-01-01

    The Arabidopsis thaliana chloroplast protein ACCELERATED CELL DEATH2 (ACD2) modulates the amount of programmed cell death (PCD) triggered by Pseudomonas syringae and protoporphyrin IX (PPIX) treatment. In vitro, ACD2 can reduce red chlorophyll catabolite, a chlorophyll derivative. We find that ACD2 shields root protoplasts that lack chlorophyll from light- and PPIX-induced PCD. Thus, chlorophyll catabolism is not obligatory for ACD2 anti-PCD function. Upon P. syringae infection, ACD2 levels and localization change in cells undergoing PCD and in their close neighbors. Thus, ACD2 shifts from being largely in chloroplasts to partitioning to chloroplasts, mitochondria, and, to a small extent, cytosol. ACD2 protects cells from PCD that requires the early mitochondrial oxidative burst. Later, the chloroplasts of dying cells generate NO, which only slightly affects cell viability. Finally, the mitochondria in dying cells have dramatically altered movements and cellular distribution. Overproduction of both ACD2 (localized to mitochondria and chloroplasts) and ascorbate peroxidase (localized to chloroplasts) greatly reduces P. syringae–induced PCD, suggesting a pro-PCD role for mitochondrial and chloroplast events. During infection, ACD2 may bind to and/or reduce PCD-inducing porphyrin-related molecules in mitochondria and possibly chloroplasts that generate reactive oxygen species, cause altered organelle behavior, and activate a cascade of PCD-inducing events. PMID:16387834

  5. Predictive Efficacy Biomarkers of Programmed Cell Death 1/Programmed Cell Death 1 Ligand Blockade Therapy.

    PubMed

    Fang, Xiao-Na; Fu, Li-Wu

    2016-01-01

    Inhibitors of immune check-point molecule, programmed cell death 1 (PD-1) and its ligand, programmed cell death ligand 1 (PD-L1) have attracted much attention in cancer immunotherapy recently due to their durable antitumor effects in various malignances, especially the advanced ones. Unfortunately, only a fraction of patients with advanced tumors could benefit from anti-PD-1/PD-L1 therapy, while others still worsened. The key to this point is that there are no efficient biomarkers for screening anti-PD-1/PD-L1-sensitive patients. In this review, we aim at summarizing the latest advances of anti-PD-1/PDL1 immunotherapy and the potential predictive efficacy biomarkers to provide evidences for identifying anti-PD-1/PDL1- sensitive patients. The present article also includes the patent review coverage on this topic. PMID:26916881

  6. α-Synuclein and neuronal cell death

    PubMed Central

    Cookson, Mark R

    2009-01-01

    α-Synuclein is a small protein that has special relevance for understanding Parkinson disease and related disorders. Not only is α-synuclein found in Lewy bodies characteristic of Parkinson disease, but also mutations in the gene for α-synuclein can cause an inherited form of Parkinson disease and expression of normal α-synuclein can increase the risk of developing Parkinson disease in sporadic, or non-familial, cases. Both sporadic and familial Parkinson disease are characterized by substantial loss of several groups of neurons, including the dopaminergic cells of the substantia nigra that are the target of most current symptomatic therapies. Therefore, it is predicted that α-synuclein, especially in its mutant forms or under conditions where its expression levels are increased, is a toxic protein in the sense that it is associated with an increased rate of neuronal cell death. This review will discuss the experimental contexts in which α-synuclein has been demonstrated to be toxic. I will also outline what is known about the mechanisms by which α-synuclein triggers neuronal damage, and identify some of the current gaps in our knowledge about this subject. Finally, the therapeutic implications of toxicity of α-synuclein will be discussed. PMID:19193223

  7. Photoreceptor cell death and rescue in retinal detachment and degenerations

    PubMed Central

    Murakami, Yusuke; Notomi, Shoji; Hisatomi, Toshio; Nakazawa, Toru; Ishibashi, Tatsuro; Miller, Joan W.; Vavvas, Demetrios G.

    2013-01-01

    Photoreceptor cell death is the ultimate cause of vision loss in various retinal disorders, including retinal detachment (RD). Photoreceptor cell death has been thought to occur mainly through apoptosis, which is the most characterized form of programmed cell death. The caspase family of cysteine proteases plays a central role for inducing apoptosis, and in experimental models of RD, dying photoreceptor cells exhibit caspase activation; however, there is a paradox that caspase inhibition alone does not provide a sufficient protection against photoreceptor cell loss, suggesting that other mechanisms of cell death are involved. Recent accumulating evidence demonstrates that non-apoptotic forms of cell death, such as autophagy and necrosis, are also regulated by specific molecular machinery, such as those mediated by autophagy-related proteins and receptor-interacting protein kinases, respectively. Here we summarize the current knowledge of cell death signaling and its roles in photoreceptor cell death after RD and other retinal degenerative diseases. A body of studies indicate that not only apoptotic but also autophagic and necrotic signaling are involved in photoreceptor cell death, and that combined targeting of these pathways may be an effective neuroprotective strategy for retinal diseases associated with photoreceptor cell loss. PMID:23994436

  8. The evolution of cell death programs as prerequisites of multicellularity.

    PubMed

    Huettenbrenner, Simone; Maier, Susanne; Leisser, Christina; Polgar, Doris; Strasser, Stephan; Grusch, Michael; Krupitza, Georg

    2003-06-01

    One of the hallmarks of multicellularity is that the individual cellular fate is sacrificed for the benefit of a higher order of life-the organism. The accidental death of cells in a multicellular organism results in swelling and membrane-rupture and inevitably spills cell contents into the surrounding tissue with deleterious effects for the organism. To avoid this form of necrotic death the cells of metazoans have developed complex self-destruction mechanisms, collectively called programmed cell death, which see to an orderly removal of superfluous cells. Since evolution never invents new genes but plays variations on old themes by DNA mutations, it is not surprising, that some of the genes involved in metazoan death pathways apparently have evolved from homologues in unicellular organisms, where they originally had different functions. Interestingly some unicellular protozoans have developed a primitive form of non-necrotic cell death themselves, which could mean that the idea of an altruistic death for the benefit of genetically identical cells predated the invention of multicellularity. The cell death pathways of protozoans, however, show no homology to those in metazoans, where several death pathways seem to have evolved in parallel. Mitochondria stands at the beginning of several death pathways and also determines, whether a cell has sufficient energy to complete a death program. However, the endosymbiotic bacterial ancestors of mitochondria are unlikely to have contributed to the recent mitochondrial death machinery and therefore, these components may derive from mutated eukaryotic precursors and might have invaded the respective mitochondrial compartments. Although there is no direct evidence, it seems that the prokaryotic-eukaryotic symbiosis created the space necessary for sophisticated death mechanisms on command, which in their distinct forms are major factors for the evolution of multicellular organisms. PMID:12787815

  9. Actin as Deathly Switch? How Auxin Can Suppress Cell-Death Related Defence

    PubMed Central

    Chang, Xiaoli; Riemann, Michael; Liu, Qiong; Nick, Peter

    2015-01-01

    Plant innate immunity is composed of two layers – a basal immunity, and a specific effector-triggered immunity, which is often accompanied by hypersensitive cell death. Initiation of cell death depends on a complex network of signalling pathways. The phytohormone auxin as central regulator of plant growth and development represents an important component for the modulation of plant defence. In our previous work, we showed that cell death is heralded by detachment of actin from the membrane. Both, actin response and cell death, are triggered by the bacterial elicitor harpin in grapevine cells. In this study we investigated, whether harpin-triggered actin bundling is necessary for harpin-triggered cell death. Since actin organisation is dependent upon auxin, we used different auxins to suppress actin bundling. Extracellular alkalinisation and transcription of defence genes as the basal immunity were examined as well as cell death. Furthermore, organisation of actin was observed in response to pharmacological manipulation of reactive oxygen species and phospholipase D. We find that induction of defence genes is independent of auxin. However, auxin can suppress harpin-induced cell death and also counteract actin bundling. We integrate our findings into a model, where harpin interferes with an auxin dependent pathway that sustains dynamic cortical actin through the activity of phospholipase D. The antagonism between growth and defence is explained by mutual competition for signal molecules such as superoxide and phosphatidic acid. Perturbations of the auxin-actin pathway might be used to detect disturbed integrity of the plasma membrane and channel defence signalling towards programmed cell death. PMID:25933033

  10. Cancer cell death by design: apoptosis, autophagy and glioma virotherapy.

    PubMed

    Tyler, Matthew A; Ulasov, Ilya V; Lesniak, Maciej S

    2009-08-01

    Autophagy has been defined as a mechanism by which oncolytic adenoviruses mediate cell killing in some cancers, including malignant glioma. Until recently, however, adenovirus replication was regarded as a process that induced classical apoptosis in the infected cell. We have assessed the method of conditionally replicating adenovirus (CRAd) death in a model of malignant glioma, considering both autophagy and apoptosis as possible mechanisms of virally-induced cell death. Our initial investigations indicated that autophagy was the predominant system in CRAd-induced cell death in glioma. This appeared to be the case in vitro; however, further investigation in vivo shows that CRAds are capable of inducing both apoptotic and autophagic cell death. In this punctum, we summarize our latest research to uncover the method of oncolytic adenovirus-induced cell death in malignant glioma. Elucidating the relationship between autophagy and apoptosis in glioma virotherapy has significant implications for the design of optimal viral vectors. PMID:19430207

  11. Analysis of cell death inducing compounds.

    PubMed

    Spicker, Jeppe S; Pedersen, Henrik Toft; Nielsen, Henrik Bjørn; Brunak, Søren

    2007-11-01

    Biomarkers for early detection of toxicity hold the promise of improving the failure rates in drug development. In the present study, gene expression levels were measured using full-genome RAE230 version 2 Affymetrix GeneChips on rat liver tissue 48 h after administration of six different compounds, three toxins (ANIT, DMN and NMF) and three non-toxins (Caeruelein, Dinitrophenol and Rosiglitazone). We identified three gene transcripts with exceptional predictive performance towards liver toxicity and/or changes in histopathology. The three genes were: glucokinase regulatory protein (GCKR), ornithine aminotransferase (OAT) and Cytochrome P450, subfamily IIC (mephenytoin 4-hydroxylase) (Cyp2C29). RT-PCR for these three genes was performed and four additional compounds were included for validation. The quantitative RT-PCR analysis confirmed the findings based on the microarray data and using the three genes a classification rate of 55 of 57 samples was achieved for the classification of not toxic versus toxic. The single most promising biomarker (OAT) alone resulted in a surprisingly 100% correctly classified samples. OAT has not previously been linked to toxicity and cell death in the literature and the novel finding represents a putative hepatotoxicity biomarker. PMID:17503021

  12. Triggering Death of Adherent Cells with Ultraviolet Radiation.

    PubMed

    Crowley, Lisa C; Waterhouse, Nigel J

    2016-01-01

    Ultraviolet (UV) radiation is a convenient stimulus for triggering cell death that is available in most laboratories. We use a Stratalinker UV cross-linker because it is a safe, cheap, reliable, consistent, and easily controlled source of UV irradiation. This protocol describes using a Stratalinker to trigger UV-induced death of HeLa cells. PMID:27371593

  13. Redox regulation of Smac mimetic-induced cell death.

    PubMed

    Fulda, Simone

    2015-01-01

    Cell death and survival programs are controlled by the cellular redox state, which is typically dysregulated during oncogenesis. A recent study reports that the inhibition of antioxidant defenses resulting from glutathione depletion can prime acute lymphoblastic leukemia cells for death induced by Smac mimetics. PMID:27308489

  14. Capsaicin induces immunogenic cell death in human osteosarcoma cells

    PubMed Central

    Jin, Tao; Wu, Hongyan; Wang, Yanlin; Peng, Hao

    2016-01-01

    Immunogenic cell death (ICD) is characterized by the early surface exposure of calreticulin (CRT). As a specific signaling molecule, CRT on the surface of apoptotic tumor cells mediates the recognition and phagocytosis of tumor cells by antigen presenting cells. To date, only a small quantity of anti-cancer chemicals have been found to induce ICD, therefore it is clinically important to identify novel chemicals that may induce ICD. The purpose of the present study is to explore the function of capsaicin in inducing ICD. In the current study, MTT assays were used to examine the growth inhibiting effects of MG-63 cells when they were treated with capsaicin or cisplatin. Mitochondrial membrane potential and western blot analysis were used to investigate capsaicin- and cisplatin-induced apoptosis. In addition, the effects of capsaicin and cisplatin were evaluated for their abilities in inducing calreticulin membrane translocation and mediating ICD in human osteosarcoma cells (MG-63). The results demonstrated that capsaicin and cisplatin can induce the apoptosis of MG-63 cells. However, only capsaicin induced a rapid translocation of CRT from the intracellular space to the cell surface. Treatment with capsaicin increased phagocytosis of MG-63 cells by dendritic cells (DCs), and these MG-63-loaded DCs could efficiently stimulate the secretion of IFN-γ by lymphocytes. These results identify capsaicin as an anti-cancer agent capable of inducing ICD in human osteosarcoma cells in vitro. PMID:27446273

  15. Mitochondrial involvement in cell death of non-mammalian eukaryotes

    PubMed Central

    Abdelwahid, Eltyeb; Rolland, Stephane; Teng, Xinchen; Conradt, Barbara; Hardwick, J. Marie; White, Kristin

    2010-01-01

    Although mitochondria are essential organelles for long-term survival of eukaryotic cells, recent discoveries in biochemistry and genetics have advanced our understanding of the requirements for mitochondria in cell death. Much of what we understand about cell death is based on the identification of conserved cell death genes in Drosophila melanogaster and Caenorhabditis elegans. However, the role of mitochondria in cell death in these models has been much less clear. Considering the active role that mitochondria play in apoptosis in mammalian cells, the mitochondrial contribution to cell death in non-mammalian systems has been an area of active investigation. In this article, we review the current research on this topic in three non-mammalian models, C. elegans, Drosophila and Saccharomyces cerevisiae. In addition, we discuss how non-mammalian models have provided important insight into the mechanisms of human disease as they relate to the mitochondrial pathway of cell death. The unique perspective derived from each of these model systems provides a more complete understanding of mitochondria in programmed cell death. PMID:20950655

  16. Ferroptosis: an iron-dependent form of nonapoptotic cell death.

    PubMed

    Dixon, Scott J; Lemberg, Kathryn M; Lamprecht, Michael R; Skouta, Rachid; Zaitsev, Eleina M; Gleason, Caroline E; Patel, Darpan N; Bauer, Andras J; Cantley, Alexandra M; Yang, Wan Seok; Morrison, Barclay; Stockwell, Brent R

    2012-05-25

    Nonapoptotic forms of cell death may facilitate the selective elimination of some tumor cells or be activated in specific pathological states. The oncogenic RAS-selective lethal small molecule erastin triggers a unique iron-dependent form of nonapoptotic cell death that we term ferroptosis. Ferroptosis is dependent upon intracellular iron, but not other metals, and is morphologically, biochemically, and genetically distinct from apoptosis, necrosis, and autophagy. We identify the small molecule ferrostatin-1 as a potent inhibitor of ferroptosis in cancer cells and glutamate-induced cell death in organotypic rat brain slices, suggesting similarities between these two processes. Indeed, erastin, like glutamate, inhibits cystine uptake by the cystine/glutamate antiporter (system x(c)(-)), creating a void in the antioxidant defenses of the cell and ultimately leading to iron-dependent, oxidative death. Thus, activation of ferroptosis results in the nonapoptotic destruction of certain cancer cells, whereas inhibition of this process may protect organisms from neurodegeneration. PMID:22632970

  17. Independent controls for neocortical neuron production and histogenetic cell death

    NASA Technical Reports Server (NTRS)

    Verney, C.; Takahashi, T.; Bhide, P. G.; Nowakowski, R. S.; Caviness, V. S. Jr

    2000-01-01

    We estimated the proportion of cells eliminated by histogenetic cell death during the first 2 postnatal weeks in areas 1, 3 and 40 of the mouse parietal neocortex. For each layer and for the subcortical white matter in each neocortical area, the number of dying cells per mm(2) was calculated and the proportionate cell death for each day of the 2-week interval was estimated. The data show that cell death proceeds essentially uniformly across the neocortical areas and layers and that it does not follow either the spatiotemporal gradient of cell cycle progression in the pseudostratified ventricular epithelium of the cerebral wall, the source of neocortical neurons, or the 'inside-out' neocortical neuronogenetic sequence. Therefore, we infer that the control mechanisms of neocortical histogenetic cell death are independent of mechanisms controlling neuronogenesis or neuronal migration but may be associated with the ingrowth, expansion and a system-wide matching of neuronal connectivity. Copyright 2000 S. Karger AG, Basel.

  18. Further considerations on in vitro skeletal muscle cell death

    PubMed Central

    Battistelli, Michela; Salucci, Sara; Burattini, Sabrina; Falcieri, Elisabetta

    2013-01-01

    Summary The present review discusses the apoptotic behavior induced by chemical and physical triggers in C2C12 skeletal muscle cells, comparing myoblast to myotube sensitivity, and investigating it by means of morphological, biochemical and cytofluorimetric analyses. After all treatments, myotubes, differently from myoblasts, showed a poor sensitivity to cell death. Intriguingly, in cells exposed to staurosporine, etoposide and UVB radiation, apoptotic and normal nuclei within the same fibercould be revealed. The presence of nuclear-dependent “territorial” death domains in the syncytium could explain a delayed cell death of myotubes compared to mononucleated cells. Moreover, autophagic granules abundantly appeared in myotubes after each treatment. Autophagy could protect muscle cell integrity against chemical and physical stimuli, making C2C12 myotubes, more resistant to cell death induction. PMID:24596689

  19. Synchronized renal tubular cell death involves ferroptosis

    PubMed Central

    Skouta, Rachid; Himmerkus, Nina; Mulay, Shrikant R.; Dewitz, Christin; De Zen, Federica; Prokai, Agnes; Zuchtriegel, Gabriele; Krombach, Fritz; Welz, Patrick-Simon; Weinlich, Ricardo; Vanden Berghe, Tom; Vandenabeele, Peter; Pasparakis, Manolis; Bleich, Markus; Weinberg, Joel M.; Reichel, Christoph A.; Bräsen, Jan Hinrich; Kunzendorf, Ulrich; Anders, Hans-Joachim; Stockwell, Brent R.; Green, Douglas R.; Krautwald, Stefan

    2014-01-01

    Receptor-interacting protein kinase 3 (RIPK3)-mediated necroptosis is thought to be the pathophysiologically predominant pathway that leads to regulated necrosis of parenchymal cells in ischemia–reperfusion injury (IRI), and loss of either Fas-associated protein with death domain (FADD) or caspase-8 is known to sensitize tissues to undergo spontaneous necroptosis. Here, we demonstrate that renal tubules do not undergo sensitization to necroptosis upon genetic ablation of either FADD or caspase-8 and that the RIPK1 inhibitor necrostatin-1 (Nec-1) does not protect freshly isolated tubules from hypoxic injury. In contrast, iron-dependent ferroptosis directly causes synchronized necrosis of renal tubules, as demonstrated by intravital microscopy in models of IRI and oxalate crystal-induced acute kidney injury. To suppress ferroptosis in vivo, we generated a novel third-generation ferrostatin (termed 16-86), which we demonstrate to be more stable, to metabolism and plasma, and more potent, compared with the first-in-class compound ferrostatin-1 (Fer-1). Even in conditions with extraordinarily severe IRI, 16-86 exerts strong protection to an extent which has not previously allowed survival in any murine setting. In addition, 16-86 further potentiates the strong protective effect on IRI mediated by combination therapy with necrostatins and compounds that inhibit mitochondrial permeability transition. Renal tubules thus represent a tissue that is not sensitized to necroptosis by loss of FADD or caspase-8. Finally, ferroptosis mediates postischemic and toxic renal necrosis, which may be therapeutically targeted by ferrostatins and by combination therapy. PMID:25385600

  20. Programmed Cell Death and Complexity in Microbial Systems.

    PubMed

    Durand, Pierre M; Sym, Stuart; Michod, Richard E

    2016-07-11

    Programmed cell death (PCD) is central to organism development and for a long time was considered a hallmark of multicellularity. Its discovery, therefore, in unicellular organisms presents compelling questions. Why did PCD evolve? What is its ecological effect on communities? To answer these questions, one is compelled to consider the impacts of PCD beyond the cell, for death obviously lowers the fitness of the cell. Here, we examine the ecological effects of PCD in different microbial scenarios and conclude that PCD can increase biological complexity. In mixed microbial communities, the mode of death affects the microenvironment, impacting the interactions between taxa. Where the population comprises groups of relatives, death has a more explicit effect. Death by lysis or other means can be harmful, while PCD can evolve by providing advantages to relatives. The synchronization of death between individuals suggests a group level property is being maintained and the mode of death also appears to have had an impact during the origin of multicellularity. PCD can result in the export of fitness from the cell to the group level via re-usable resources and PCD may also provide a mechanism for how groups beget new groups comprising kin. Furthermore, PCD is a means for solving a central problem of group living - the toxic effects of death - by making resources in dying cells beneficial to others. What emerges from the data reviewed here is that while PCD carries an obvious cost to the cell, it can be a driver of complexity in microbial communities. PMID:27404254

  1. Sorafenib-induced defective autophagy promotes cell death by necroptosis

    PubMed Central

    Kharaziha, Pedram; Chioureas, Dimitris; Baltatzis, George; Fonseca, Pedro; Rodriguez, Patricia; Gogvadze, Vladimir; Lennartsson, Lena; Björklund, Ann-Charlotte; Zhivotovsky, Boris; Grandér, Dan; Egevad, Lars; Nilsson, Sten; Panaretakis, Theocharis

    2015-01-01

    Autophagy is one of the main cytoprotective mechanisms that cancer cells deploy to withstand the cytotoxic stress and survive the lethal damage induced by anti-cancer drugs. However, under specific conditions, autophagy may, directly or indirectly, induce cell death. In our study, treatment of the Atg5-deficient DU145 prostate cancer cells, with the multi-tyrosine kinase inhibitor, sorafenib, induces mitochondrial damage, autophagy and cell death. Molecular inhibition of autophagy by silencing ULK1 and Beclin1 rescues DU145 cells from cell death indicating that, in this setting, autophagy promotes cell death. Re-expression of Atg5 restores the lipidation of LC3 and rescues DU145 and MEF atg5−/− cells from sorafenib-induced cell death. Despite the lack of Atg5 expression and LC3 lipidation, DU145 cells form autophagosomes as demonstrated by transmission and immuno-electron microscopy, and the formation of LC3 positive foci. However, the lack of cellular content in the autophagosomes, the accumulation of long-lived proteins, the presence of GFP-RFP-LC3 positive foci and the accumulated p62 protein levels indicate that these autophagosomes may not be fully functional. DU145 cells treated with sorafenib undergo a caspase-independent cell death that is inhibited by the RIPK1 inhibitor, necrostatin-1. Furthermore, treatment with sorafenib induces the interaction of RIPK1 with p62, as demonstrated by immunoprecipitation and a proximity ligation assay. Silencing of p62 decreases the RIPK1 protein levels and renders necrostatin-1 ineffective in blocking sorafenib-induced cell death. In summary, the formation of Atg5-deficient autophagosomes in response to sorafenib promotes the interaction of p62 with RIPK leading to cell death by necroptosis. PMID:26416459

  2. Do all programmed cell deaths occur via apoptosis?

    PubMed Central

    Schwartz, L M; Smith, S W; Jones, M E; Osborne, B A

    1993-01-01

    During development, large numbers of cells die by a nonpathological process referred to as programmed cell death. In many tissues, dying cells display similar changes in morphology and chromosomal DNA organization, which has been termed apoptosis. Apoptosis is such a widely documented phenomenon that many authors have assumed all programmed cell deaths occur by this process. Two well-characterized model systems for programmed cell death are (i) the death of T cells during negative selection in the mouse thymus and (ii) the loss of intersegmental muscles of the moth Manduca sexta at the end of metamorphosis. In this report we compare the patterns of cell death displayed by T cells and the intersegmental muscles and find that they differ in terms of cell-surface morphology, nuclear ultrastructure, DNA fragmentation, and polyubiquitin gene expression. Unlike the T cells, which are known to die via apoptosis, we find that the intersegmental muscles display few of the features that characterize apoptosis. These data suggest that more than one cell death mechanism is used during development. Images PMID:8430112

  3. Host-Cell Survival and Death During Chlamydia Infection

    PubMed Central

    Ying, Songmin; Pettengill, Matthew; Ojcius, David M.; Häcker, Georg

    2008-01-01

    Different Chlamydia trachomatis strains are responsible for prevalent bacterial sexually-transmitted disease and represent the leading cause of preventable blindness worldwide. Factors that predispose individuals to disease and mechanisms by which chlamydiae cause inflammation and tissue damage remain unclear. Results from recent studies indicate that prolonged survival and subsequent death of infected cells and their effect on immune effector cells during chlamydial infection may be important in determining the outcome. Survival of infected cells is favored at early times of infection through inhibition of the mitochondrial pathway of apoptosis. Death at later times displays features of both apoptosis and necrosis, but pro-apoptotic caspases are not involved. Most studies on chlamydial modulation of host-cell death until now have been performed in cell lines. The consequences for pathogenesis and the immune response will require animal models of chlamydial infection, preferably mice with targeted deletions of genes that play a role in cell survival and death. PMID:18843378

  4. Mitochondrial and Nuclear Cross Talk in Cell Death: Parthanatos

    PubMed Central

    Andrabi, Shaida A.; Dawson, Ted M.; Dawson, Valina L.

    2015-01-01

    Poly(ADP-ribose) polymerase-1 (PARP-1) PARP-1 is an abundant nuclear protein first described to facilitate DNA base excision repair. Recent work has expanded the physiologic functions of PARP-1 and it is clear that the full range of biologic actions of this important protein are not yet fully understood. Regulation of the product of PARP-1, poly(ADP-ribose) (PAR), is a dynamic process with poly(ADP-ribose) glycohydrolase (PARG) playing a major role in the degradation of the polymer. Under pathophysiologic situations, over activation of poly(ADP-ribose) polymerase-1 (PARP-1) results in unregulated PAR synthesis and widespread neuronal cell death. Once thought to be necrotic cell death due to energy failure, we recently found that PARP-1 dependent cell death is dependent on the generation of PAR that triggers nuclear translocation of apoptosis-inducing factor (AIF) to result in caspase-independent cell death. This form of cell death is distinct from apoptosis, necrosis or autophagy and is termed Parthanatos. PARP-1 dependent cell death has been implicated in tissues throughout the body and in diseases afflicting hundreds of millions world wide including stroke, Parkinson's disease, heart attack, diabetes, and ischemia reperfusion injury in numerous tissues. The breadth of indications for PARP-1 injury make Parthanatos a clinically important form of cell death to understand and control. PMID:19076445

  5. Mitochondria and calcium: from cell signalling to cell death

    PubMed Central

    Duchen, Michael R

    2000-01-01

    While a pathway for Ca2+ accumulation into mitochondria has long been established, its functional significance is only now becoming clear in relation to cell physiology and pathophysiology. The observation that mitochondria take up Ca2+ during physiological Ca2+ signalling in a variety of cell types leads to four questions: (i) ‘What is the impact of mitochondrial Ca2+ uptake on mitochondrial function?’ (ii) ‘What is the impact of mitochondrial Ca2+ uptake on Ca2+ signalling?’ (iii) ‘What are the consequences of impaired mitochondrial Ca2+ uptake for cell function?’ and finally (iv) ‘What are the consequences of pathological [Ca2+]c signalling for mitochondrial function?’ These will be addressed in turn. Thus: (i) accumulation of Ca2+ into mitochondria regulates mitochondrial metabolism and causes a transient depolarisation of mitochondrial membrane potential. (ii) Mitochondria may act as a spatial Ca2+ buffer in many cells, regulating the local Ca2+ concentration in cellular microdomains. This process regulates processes dependent on local cytoplasmic Ca2+ concentration ([Ca2+]c), particularly the flux of Ca2+ through IP3-gated channels of the endoplasmic reticulum (ER) and the channels mediating capacitative Ca2+ influx through the plasma membrane. Consequently, mitochondrial Ca2+ uptake plays a substantial role in shaping [Ca2+]c signals in many cell types. (iii) Impaired mitochondrial Ca2+ uptake alters the spatiotemporal characteristics of cellular [Ca2+]c signalling and downregulates mitochondrial metabolism. (iv) Under pathological conditions of cellular [Ca2+]c overload, particularly in association with oxidative stress, mitochondrial Ca2+ uptake may trigger pathological states that lead to cell death. In the model of glutamate excitotoxicity, microdomains of [Ca2+]c are apparently central, as the pathway to cell death seems to require the local activation of neuronal nitric oxide synthase (nNOS), itself held by scaffolding proteins in close

  6. Mechanical Stress Promotes Cisplatin-Induced Hepatocellular Carcinoma Cell Death

    PubMed Central

    Riad, Sandra; Bougherara, Habiba

    2015-01-01

    Cisplatin (CisPt) is a commonly used platinum-based chemotherapeutic agent. Its efficacy is limited due to drug resistance and multiple side effects, thereby warranting a new approach to improving the pharmacological effect of CisPt. A newly developed mathematical hypothesis suggested that mechanical loading, when coupled with a chemotherapeutic drug such as CisPt and immune cells, would boost tumor cell death. The current study investigated the aforementioned mathematical hypothesis by exposing human hepatocellular liver carcinoma (HepG2) cells to CisPt, peripheral blood mononuclear cells, and mechanical stress individually and in combination. HepG2 cells were also treated with a mixture of CisPt and carnosine with and without mechanical stress to examine one possible mechanism employed by mechanical stress to enhance CisPt effects. Carnosine is a dipeptide that reportedly sequesters platinum-based drugs away from their pharmacological target-site. Mechanical stress was achieved using an orbital shaker that produced 300 rpm with a horizontal circular motion. Our results demonstrated that mechanical stress promoted CisPt-induced death of HepG2 cells (~35% more cell death). Moreover, results showed that CisPt-induced death was compromised when CisPt was left to mix with carnosine 24 hours preceding treatment. Mechanical stress, however, ameliorated cell death (20% more cell death). PMID:25685789

  7. Sickle cell trait and sudden death--bringing it home.

    PubMed Central

    Mitchell, Bruce L.

    2007-01-01

    Sickle cell trait continues to be the leading cause of sudden death for young African Americans in military basic training and civilian organized sports. The syndrome may have caused the death of up to 10 college football players since 1974 and, as recently as 2000, was suspected as the cause of death of three U.S. Army recruits. The penal military-style boot camps in the United States and the recent death of two teenagers with sickle cell trait merits renewed vigor in the education of athletic instructors, the military and the public about conditions associated with sudden death in individuals with sickle cell trait. Images Figure 1 Figure 2 PMID:17393956

  8. Modelling radiation-induced cell death and tumour re-oxygenation: local versus global and instant versus delayed cell death

    NASA Astrophysics Data System (ADS)

    Gago-Arias, Araceli; Aguiar, Pablo; Espinoza, Ignacio; Sánchez-Nieto, Beatriz; Pardo-Montero, Juan

    2016-02-01

    The resistance of hypoxic cells to radiation, due to the oxygen dependence of radiosensitivity, is well known and must be taken into account to accurately calculate the radiation induced cell death. A proper modelling of the response of tumours to radiation requires deriving the distribution of oxygen at a microscopic scale. This usually involves solving the reaction-diffusion equation in tumour voxels using a vascularization distribution model. Moreover, re-oxygenation arises during the course of radiotherapy, one reason being the increase of available oxygen caused by cell killing, which can turn hypoxic tumours into oxic. In this work we study the effect of cell death kinetics in tumour oxygenation modelling, analysing how it affects the timing of re-oxygenation, surviving fraction and tumour control. Two models of cell death are compared, an instantaneous cell killing, mimicking early apoptosis, and a delayed cell death scenario in which cells can die shortly after being damaged, as well as long after irradiation. For each of these scenarios, the decrease in oxygen consumption due to cell death can be computed globally (macroscopic voxel average) or locally (microscopic). A re-oxygenation model already used in the literature, the so called full re-oxygenation, is also considered. The impact of cell death kinetics and re-oxygenation on tumour responses is illustrated for two radiotherapy fractionation schemes: a conventional schedule, and a hypofractionated treatment. The results show large differences in the doses needed to achieve 50% tumour control for the investigated cell death models. Moreover, the models affect the tumour responses differently depending on the treatment schedule. This corroborates the complex nature of re-oxygenation, showing the need to take into account the kinetics of cell death in radiation response models.

  9. Superoxide radical-generating compounds activate a predicted promoter site for paraquat-inducible genes of the Chromobacterium violaceum bacterium in a dose-dependent manner.

    PubMed

    Gabriel, J E; Guerra-Slompo, E P; de Souza, E M; de Carvalho, F A L; Madeira, H M F; de Vasconcelos, A T R

    2015-01-01

    The purpose of the present study was to functionally evaluate the influence of superoxide radical-generating compounds on the heterologous induction of a predicted promoter region of open reading frames for paraquat-inducible genes (pqi genes) revealed during genome annotation analyses of the Chromobacterium violaceum bacterium. A 388-bp fragment corresponding to a pqi gene promoter of C. violaceum was amplified using specific primers and cloned into a conjugative vector containing the Escherichia coli lacZ gene without a promoter. Assessments of the expression of the β-galactosidase enzyme were performed in the presence of menadione (MEN) and phenazine methosulfate (PMS) compounds at different final concentrations to evaluate the heterologous activation of the predicted promoter region of interest in C. violaceum induced by these substrates. Under these experimental conditions, the MEN reagent promoted highly significant increases in the expression of the β-galactosidase enzyme modulated by activating the promoter region of the pqi genes at all concentrations tested. On the other hand, significantly higher levels in the expression of the β-galactosidase enzyme were detected exclusively in the presence of the PMS reagent at a final concentration of 50 μg/mL. The findings described in the present study demonstrate that superoxide radical-generating compounds can activate a predicted promoter DNA motif for pqi genes of the C. violaceum bacterium in a dose-dependent manner. PMID:26345950

  10. Increased Expression of SVCT2 in a New Mouse Model Raises Ascorbic Acid in Tissues and Protects against Paraquat-Induced Oxidative Damage in Lung

    PubMed Central

    Harrison, Fiona Edith; Best, Jennifer Lee; Meredith, Martha Elizabeth; Gamlin, Clare Ruth; Borza, Dorin-Bogdan; May, James Michael

    2012-01-01

    A new transgenic mouse model for global increases in the Sodium Dependent Vitamin C transporter 2 (SVCT2) has been generated. The SVCT2-Tg mouse shows increased SVCT2 mRNA levels in all organs tested and correspondingly increased ascorbic acid (ASC) levels in all organs except liver. The extent of the increase in transporter mRNA expression differed among mice and among organs. The increased ASC levels did not have any adverse effects on behavior in the SVCT2-Tg mice, which did not differ from wild-type mice on tests of locomotor activity, anxiety, sensorimotor or cognitive ability. High levels of SVCT2 and ASC were found in the kidneys of SVCT2-Tg mice and urinary albumin excretion was lower in these mice than in wild-types. No gross pathological changes were noted in kidneys from SVCT2-Tg mice. SVCT2 immunoreactivity was detected in both SVCT2 and wild-type mice, and a stronger signal was seen in tubules than in glomeruli. Six treatments with Paraquat (3x10 and 3x15 mg/kg i.p.) were used to induce oxidative stress in mice. SVCT2-Tg mice showed a clear attenuation of Paraquat-induced oxidative stress in lung, as measured by F2-isoprostanes. Paraquat also decreased SVCT2 mRNA signal in liver, lung and kidney in SVCT2-Tg mice. PMID:22558179

  11. Increased expression of SVCT2 in a new mouse model raises ascorbic acid in tissues and protects against paraquat-induced oxidative damage in lung.

    PubMed

    Harrison, Fiona Edith; Best, Jennifer Lee; Meredith, Martha Elizabeth; Gamlin, Clare Ruth; Borza, Dorin-Bogdan; May, James Marion; May, James Michael

    2012-01-01

    A new transgenic mouse model for global increases in the Sodium Dependent Vitamin C transporter 2 (SVCT2) has been generated. The SVCT2-Tg mouse shows increased SVCT2 mRNA levels in all organs tested and correspondingly increased ascorbic acid (ASC) levels in all organs except liver. The extent of the increase in transporter mRNA expression differed among mice and among organs. The increased ASC levels did not have any adverse effects on behavior in the SVCT2-Tg mice, which did not differ from wild-type mice on tests of locomotor activity, anxiety, sensorimotor or cognitive ability. High levels of SVCT2 and ASC were found in the kidneys of SVCT2-Tg mice and urinary albumin excretion was lower in these mice than in wild-types. No gross pathological changes were noted in kidneys from SVCT2-Tg mice. SVCT2 immunoreactivity was detected in both SVCT2 and wild-type mice, and a stronger signal was seen in tubules than in glomeruli. Six treatments with Paraquat (3x10 and 3x15 mg/kg i.p.) were used to induce oxidative stress in mice. SVCT2-Tg mice showed a clear attenuation of Paraquat-induced oxidative stress in lung, as measured by F(2)-isoprostanes. Paraquat also decreased SVCT2 mRNA signal in liver, lung and kidney in SVCT2-Tg mice. PMID:22558179

  12. Timing determines dexamethasone and rituximab induced synergistic cell death.

    PubMed

    Adem, Jemal; Eray, Mine; Eeva, Jonna; Nuutinen, Ulla; Pelkonen, Jukka

    2016-07-01

    Dysregulation of cell death signaling pathways in many cell types such as B lymphocytes (B-cells) can lead to cancer, for example to B-cell lymphomas. Rituximab (RTX) and glucocorticoids such as dexamethasone (Dex) are widely used to treat hematological malignancies including B-cell lymphomas. Although the combination of Dex and RTX improves the treatment outcome of lymphoma patients, most lymphomas remain incurable diseases. Therefore, a detailed investigation of Dex- and RTX-induced signaling might provide new insights into the therapeutic benefits of these drugs. In this paper, we describe Dex- and RTX-induced signaling pathways and their downstream target proteins/cells. In addition, we also overview how the signaling initiated by Dex and RTX modulate the outcome of Dex- and RTX-mediated cell death in lymphoma cells. The combination of Dex and RTX results in massive cell death in lymphoma cells. However, pretreatment of lymphoma cells or mononuclear cytotoxic cells with Dex followed by RTX leads to a decrease in apoptosis or it impairs antibody-dependent cellular cytotoxicity (ADCC). RTX-mediated ADCC is impaired by Dex-induced depletion of cytotoxic cells, whereas RTX-mediated short-term ERK1/2 activation decreases Dex-induced apoptosis. Therefore, the timing of the combination of Dex and RTX is a determining factor for the synergistic effect of these cell death inducing agents. PMID:27290654

  13. Polyoma small T antigen triggers cell death via mitotic catastrophe.

    PubMed

    Pores Fernando, A T; Andrabi, S; Cizmecioglu, O; Zhu, C; Livingston, D M; Higgins, J M G; Schaffhausen, B S; Roberts, T M

    2015-05-01

    Polyoma small T antigen (PyST), an early gene product of the polyoma virus, has been shown to cause cell death in a number of mammalian cells in a protein phosphatase 2A (PP2A)-dependent manner. In the current study, using a cell line featuring regulated expression of PyST, we found that PyST arrests cells in mitosis. Live-cell and immunofluorescence studies showed that the majority of the PyST expressing cells were arrested in prometaphase with almost no cells progressing beyond metaphase. These cells exhibited defects in chromosomal congression, sister chromatid cohesion and spindle positioning, thereby resulting in the activation of the spindle assembly checkpoint. Prolonged mitotic arrest then led to cell death via mitotic catastrophe. Cell cycle inhibitors that block cells in G1/S prevented PyST-induced death. PyST-induced cell death that occurs during M is not dependent on p53 status. These data suggested, and our results confirmed, that PP2A inhibition could be used to preferentially kill cancer cells with p53 mutations that proliferate normally in the presence of cell cycle inhibitors. PMID:24998850

  14. Heme oxygenase-1 accelerates erastin-induced ferroptotic cell death

    PubMed Central

    Kwon, Min-Young; Park, Eunhee

    2015-01-01

    The oncogenic RAS-selective lethal small molecule Erastin triggers a unique iron-dependent form of nonapoptotic cell death termed ferroptosis. Ferroptosis is dependent upon the production of intracellular iron-dependent reactive oxygen species (ROS), but not other metals. However, key regulators remain unknown. The heme oxygenase (HO) is a major intracellular source of iron. In this study, the role of heme oxygenase in Erastin-triggered ferroptotic cancer cell death has been investigated. Zinc protoporphyrin IX (ZnPP), a HO-1 inhibitor, prevented Erastin-triggered ferroptotic cancer cell death. Furthermore, Erastin induced the protein and mRNA levels of HO-1 in HT-1080 fibrosarcoma cells. HO-1+/+ and HO-1−/− fibroblast, HO-1 overexpression, and chycloheximide-treated experiments revealed that the expression of HO-1 has a decisive effects in Erastin-triggered cell death. Hemin and CO-releasing molecules (CORM) promote Erastin-induced ferroptotic cell death, not by biliverdin and bilirubin. In addition, hemin and CORM accelerate the HO-1 expression in the presence of Erastin and increase membranous lipid peroxidation. Thus, HO-1 is an essential enzyme for iron-dependent lipid peroxidation during ferroptotic cell death. PMID:26405158

  15. Analysis of Cell Death Induction in Intestinal Organoids In Vitro.

    PubMed

    Grabinger, Thomas; Delgado, Eugenia; Brunner, Thomas

    2016-01-01

    The intestinal epithelium has an important function in the absorption of nutrients contained in the food. Furthermore, it also has an important barrier function, preventing luminal pathogens from entering the bloodstream. This single cell layer epithelium is quite sensitive to various cell death-promoting triggers, including drugs, irradiation, and TNF family members, leading to loss of barrier integrity, epithelial erosion, inflammation, malabsorption, and diarrhea. In order to assess the intestinal epithelium-damaging potential of treatments and substances specific test systems are required. As intestinal tumor cell lines are a poor substitute for primary intestinal epithelial cells, and in vivo experiments in mice are costly and often unethical, the use of intestinal organoids cultured from intestinal crypts provide an ideal tool to study cell death induction and mechanisms in primary intestinal epithelial cells. This protocol describes the isolation and culture of intestinal organoids from murine small intestinal crypts, and the quantitative assessment of cell death induction in these organoids. PMID:27108433

  16. Human Haploid Cell Genetics Reveals Roles for Lipid Metabolism Genes in Nonapoptotic Cell Death

    PubMed Central

    2016-01-01

    Little is known about the regulation of nonapoptotic cell death. Using massive insertional mutagenesis of haploid KBM7 cells we identified nine genes involved in small-molecule-induced nonapoptotic cell death, including mediators of fatty acid metabolism (ACSL4) and lipid remodeling (LPCAT3) in ferroptosis. One novel compound, CIL56, triggered cell death dependent upon the rate-limiting de novo lipid synthetic enzyme ACC1. These results provide insight into the genetic regulation of cell death and highlight the central role of lipid metabolism in nonapoptotic cell death. PMID:25965523

  17. The intersection of cell death and inflammasome activation.

    PubMed

    Vince, James E; Silke, John

    2016-06-01

    Inflammasomes sense cellular danger to activate the cysteine-aspartic protease caspase-1, which processes precursor interleukin-1β (IL-1β) and IL-18 into their mature bioactive fragments. In addition, activated caspase-1 or the related inflammatory caspase, caspase-11, can cleave gasdermin D to induce a lytic cell death, termed pyroptosis. The intertwining of IL-1β activation and cell death is further highlighted by research showing that the extrinsic apoptotic caspase, caspase-8, may, like caspase-1, directly process IL-1β, activate the NLRP3 inflammasome itself, or bind to inflammasome complexes to induce apoptotic cell death. Similarly, RIPK3- and MLKL-dependent necroptotic signaling can activate the NLRP3 inflammasome to drive IL-1β inflammatory responses in vivo. Here, we review the mechanisms by which cell death signaling activates inflammasomes to initiate IL-1β-driven inflammation, and highlight the clinical relevance of these findings to heritable autoinflammatory diseases. We also discuss whether the act of cell death can be separated from IL-1β secretion and evaluate studies suggesting that several cell death regulatory proteins can directly interact with, and modulate the function of, inflammasome and IL-1β containing protein complexes. PMID:27066895

  18. Targeting Cell Death Pathways for Therapeutic Intervention in Kidney Diseases.

    PubMed

    Garg, Jay P; Vucic, Domagoj

    2016-05-01

    Precise regulation of cell death and survival is essential for proper maintenance of organismal homeostasis, development, and the immune system. Deregulated cell death can lead to developmental defects, neuropathies, infections, and cancer. Kidney diseases, especially acute pathologies linked to ischemia-reperfusion injury, are among illnesses that profoundly are affected by improper regulation or execution of cell death pathways. Attempts to develop medicines for kidney diseases have been impacted by the complexity of these pathologies given the heterogeneous patient population and diverse etiologies. By analyzing cell death pathways activated in kidney diseases, we attempt to differentiate their importance for these pathologies with a goal of identifying those that have more profound impact and the best therapeutic potential. Although classic apoptosis still might be important, regulated necrosis pathways including necroptosis, ferroptosis, parthanatos, and mitochondrial permeability transition-associated cell death play a significantly role in kidney diseases, especially in acute kidney pathologies. Although targeting receptor-interacting protein 1 kinase appears to be the best therapeutic strategy, combination with inhibitors of other cell death pathways is likely to bring superior benefit and possible cure to patients suffering from kidney diseases. PMID:27339381

  19. Inhibition of regulated cell death by cell-penetrating peptides.

    PubMed

    Krautwald, Stefan; Dewitz, Christin; Fändrich, Fred; Kunzendorf, Ulrich

    2016-06-01

    Development of the means to efficiently and continuously renew missing and non-functional proteins in diseased cells remains a major goal in modern molecular medicine. While gene therapy has the potential to achieve this, substantial obstacles must be overcome before clinical application can be considered. A promising alternative approach is the direct delivery of non-permeant active biomolecules, such as oligonucleotides, peptides and proteins, to the affected cells with the purpose of ameliorating an advanced disease process. In addition to receptor-mediated endocytosis, cell-penetrating peptides are widely used as vectors for rapid translocation of conjugated molecules across cell membranes into intracellular compartments and the delivery of these therapeutic molecules is generally referred to as novel prospective protein therapy. As a broad coverage of the enormous amount of published data in this field is unrewarding, this review will provide a brief, focused overview of the technology and a summary of recent studies of the most commonly used protein transduction domains and their potential as therapeutic agents for the treatment of cellular damage and the prevention of regulated cell death. PMID:27048815

  20. Prodigiosin inhibits motility and activates bacterial cell death revealing molecular biomarkers of programmed cell death.

    PubMed

    Darshan, N; Manonmani, H K

    2016-12-01

    The antimicrobial activity of prodigiosin from Serratia nematodiphila darsh1, a bacterial pigment was tested against few food borne bacterial pathogens Bacillus cereus, Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli. The mode of action of prodigiosin was studied. Prodigiosin induced bactericidal activity indicating a stereotypical set of biochemical and morphological feature of Programmed cell death (PCD). PCD involves DNA fragmentation, generation of ROS, and expression of a protein with caspase-like substrate specificity in bacterial cells. Prodigiosin was observed to be internalized into bacterial cells and was localized predominantly in the membrane and the nuclear fraction, thus, facilitating intracellular trafficking and then binding of prodigiosin to the bacterial DNA. Corresponding to an increasing concentration of prodigiosin, the level of certain proteases were observed to increase in bacteria studied, thus initiating the onset of PCD. Prodigiosin at a sub-inhibitory concentration inhibits motility of pathogens. Our observations indicated that prodigiosin could be a promising antibacterial agent and could be used in the prevention of bacterial infections. PMID:27460563

  1. Enucleation: a possible mechanism of cancer cell death

    PubMed Central

    Paunescu, Virgil; Bojin, Florina M; Gavriliuc, Oana I; Taculescu, Elena A; Ianos, Robert; Ordodi, Valentin L; Iman, Vlad F; Tatu, Calin A

    2014-01-01

    There are few major morphologies of cell death that have been described so far: apoptosis (type I), cell death associated with autophagy (type II), necrosis (type III) and anchorage-dependent mechanisms—anoikis. Here, we show for the first time a possibly novel mechanism inducing tumour cell death under in vitro conditions—enucleation. We pursued the influence of colloidal suspensions of Fe3O4 nanoparticles on tumour cell lines (SK-BR-3 and MCF-7 breast cancer cell lines) grown according to standard cell culture protocols. Magnetite nanoparticles were prepared by combustion synthesis and double layer coated with oleic acid. Scanning and transmission electron microscopy revealed that tumour cells developed a network of intracytoplasmic stress fibres, which induce extrusion of nuclei, and enucleated cells die. Normal adult mesenchymal stem cells, used as control, did not exhibit the same behaviour. Intact nuclei were found in culture supernatant of tumour cells, and were visualized by immunofluorescence. Enucleation as a potential mechanism of tumour cell death might open new horizons in cancer biology research and development of therapeutic agents capable of exploiting this behaviour. PMID:24629135

  2. Morphological and cytochemical determination of cell death by apoptosis

    PubMed Central

    Sobel, Burton E.; Budd, Ralph C.

    2007-01-01

    Several modes of cell death are now recognized, including necrosis, apoptosis, and autophagy. Oftentimes the distinctions between these various modes may not be apparent, although the precise mode may be physiologically important. Accordingly, it is often desirable to be able to classify the mode of cell death. Apoptosis was originally defined by structural alterations in cells observable by transmitted light and electron microscopy. Today, a wide variety of imaging and cytochemical techniques are available for the investigation of apoptosis. This review will highlight many of these methods, and provide a critique on the advantages and disadvantages associated with them for the specific identification of apoptotic cells in culture and tissues. PMID:18000678

  3. Interaction of Mycobacterium tuberculosis with Host Cell Death Pathways

    PubMed Central

    Srinivasan, Lalitha; Ahlbrand, Sarah; Briken, Volker

    2014-01-01

    Mycobacterium tuberculosis (Mtb) has coevolved with humans for tens of thousands of years. It is thus highly adapted to its human host and has evolved multiple mechanisms to manipulate host immune responses to its advantage. One central host pathogen interaction modality is host cell death pathways. Host cell apoptosis is associated with a protective response to Mtb infection, whereas a necrotic response favors the pathogen. Consistently, Mtb inhibits host cell apoptosis signaling but promotes induction of programmed necrosis. The molecular mechanisms involved in Mtb-mediated host cell death manipulation, the consequences for host immunity, and the potential for therapeutic and preventive approaches will be discussed. PMID:24968864

  4. Measuring Cell Death by Propidium Iodide Uptake and Flow Cytometry.

    PubMed

    Crowley, Lisa C; Scott, Adrian P; Marfell, Brooke J; Boughaba, Jeanne A; Chojnowski, Grace; Waterhouse, Nigel J

    2016-01-01

    Propidium iodide (PI) is a small fluorescent molecule that binds to DNA but cannot passively traverse into cells that possess an intact plasma membrane. PI uptake versus exclusion can be used to discriminate dead cells, in which plasma membranes become permeable regardless of the mechanism of death, from live cells with intact membranes. PI is excited by wavelengths between 400 and 600 nm and emits light between 600 and 700 nm, and is therefore compatible with lasers and photodetectors commonly available in flow cytometers. This protocol for PI staining can be used to quantitate cell death in most modern research facilities and universities. PMID:27371595

  5. Paraptosis-like cell death induced by yessotoxin.

    PubMed

    Korsnes, Mónica Suárez; Espenes, Arild; Hetland, Dyveke Lem; Hermansen, Lene C

    2011-12-01

    This study shows that BC3H1 myoblast cell lines exposed to 100 nM yessotoxin (YTX) undergo a form of programmed cell death distinct from apoptosis and with features resembling paraptosis. Morphologically, cells treated with YTX reveal extensive cytoplasmic vacuolation, mitochondrial and endoplasmic reticulum swelling, uncondensed chromatin and cytoskeletal alterations. DNA electrophoresis evidences lack of DNA fragmentation and Western blotting analysis demonstrates activation of the mitogen-activated protein kinase JNK/SAPK1. Further characterisation of this form of programmed cell death may have interest within medicine and cancer therapy. PMID:21945047

  6. Targeting Cell Survival Proteins for Cancer Cell Death

    PubMed Central

    Pandey, Manoj K.; Prasad, Sahdeo; Tyagi, Amit Kumar; Deb, Lokesh; Huang, Jiamin; Karelia, Deepkamal N.; Amin, Shantu G.; Aggarwal, Bharat B.

    2016-01-01

    Escaping from cell death is one of the adaptations that enable cancer cells to stave off anticancer therapies. The key players in avoiding apoptosis are collectively known as survival proteins. Survival proteins comprise the Bcl-2, inhibitor of apoptosis (IAP), and heat shock protein (HSP) families. The aberrant expression of these proteins is associated with a range of biological activities that promote cancer cell survival, proliferation, and resistance to therapy. Several therapeutic strategies that target survival proteins are based on mimicking BH3 domains or the IAP-binding motif or competing with ATP for the Hsp90 ATP-binding pocket. Alternative strategies, including use of nutraceuticals, transcriptional repression, and antisense oligonucleotides, provide options to target survival proteins. This review focuses on the role of survival proteins in chemoresistance and current therapeutic strategies in preclinical or clinical trials that target survival protein signaling pathways. Recent approaches to target survival proteins-including nutraceuticals, small-molecule inhibitors, peptides, and Bcl-2-specific mimetic are explored. Therapeutic inventions targeting survival proteins are promising strategies to inhibit cancer cell survival and chemoresistance. However, complete eradication of resistance is a distant dream. For a successful clinical outcome, pretreatment with novel survival protein inhibitors alone or in combination with conventional therapies holds great promise. PMID:26927133

  7. Targeting Cell Survival Proteins for Cancer Cell Death.

    PubMed

    Pandey, Manoj K; Prasad, Sahdeo; Tyagi, Amit Kumar; Deb, Lokesh; Huang, Jiamin; Karelia, Deepkamal N; Amin, Shantu G; Aggarwal, Bharat B

    2016-01-01

    Escaping from cell death is one of the adaptations that enable cancer cells to stave off anticancer therapies. The key players in avoiding apoptosis are collectively known as survival proteins. Survival proteins comprise the Bcl-2, inhibitor of apoptosis (IAP), and heat shock protein (HSP) families. The aberrant expression of these proteins is associated with a range of biological activities that promote cancer cell survival, proliferation, and resistance to therapy. Several therapeutic strategies that target survival proteins are based on mimicking BH3 domains or the IAP-binding motif or competing with ATP for the Hsp90 ATP-binding pocket. Alternative strategies, including use of nutraceuticals, transcriptional repression, and antisense oligonucleotides, provide options to target survival proteins. This review focuses on the role of survival proteins in chemoresistance and current therapeutic strategies in preclinical or clinical trials that target survival protein signaling pathways. Recent approaches to target survival proteins-including nutraceuticals, small-molecule inhibitors, peptides, and Bcl-2-specific mimetic are explored. Therapeutic inventions targeting survival proteins are promising strategies to inhibit cancer cell survival and chemoresistance. However, complete eradication of resistance is a distant dream. For a successful clinical outcome, pretreatment with novel survival protein inhibitors alone or in combination with conventional therapies holds great promise. PMID:26927133

  8. Acetaminophen Induces Human Neuroblastoma Cell Death through NFKB Activation

    PubMed Central

    Posadas, Inmaculada; Santos, Pablo; Ceña, Valentín

    2012-01-01

    Neuroblastoma resistance to apoptosis may contribute to the aggressive behavior of this tumor. Therefore, it would be relevant to activate endogenous cellular death mechanisms as a way to improve neuroblastoma therapy. We used the neuroblastoma SH-SY5Y cell line as a model to study the mechanisms involved in acetaminophen (AAP)-mediated toxicity by measuring CYP2E1 enzymatic activity, NFkB p65 subunit activation and translocation to the nucleus, Bax accumulation into the mitochondria, cytochrome c release and caspase activation. AAP activates the intrinsic death pathway in the SH-SY5Y human neuroblastoma cell line. AAP metabolism is partially responsible for this activation, because blockade of the cytochrome CYP2E1 significantly reduced but did not totally prevent, AAP-induced SH-SY5Y cell death. AAP also induced NFkB p65 activation by phosphorylation and its translocation to the nucleus, where NFkB p65 increased IL-1β production. This increase contributed to neuroblastoma cell death through a mechanism involving Bax accumulation into the mitochondria, cytochrome c release and caspase3 activation. Blockade of NFkB translocation to the nucleus by the peptide SN50 prevented AAP-mediated cell death and IL-1β production. Moreover, overexpression of the antiapoptotic protein Bcl-xL did not decrease AAP-mediated IL-1β production, but prevented both AAP and IL-1β-mediated cell death. We also confirmed the AAP toxic actions on SK-N-MC neuroepithelioma and U87MG glioblastoma cell lines. The results presented here suggest that AAP activates the intrinsic death pathway in neuroblastoma cells through a mechanism involving NFkB and IL-1β. PMID:23166834

  9. Bax-induced cell death in Candida albicans.

    PubMed

    De Smet, Kris; Eberhardt, Ines; Reekmans, Rieka; Contreras, Roland

    2004-12-01

    Bax is a pro-apoptotic member of the Bcl-2 family of proteins involved in the regulation of genetically programmed cell death in mammalian cells. It has been shown that heterologous expression of Bax in several yeast species, such as Saccharomyces cerevisiae, Schizosaccharomyces pombe and Pichia pastoris, also induces cell death. In this study we investigated the effects of Bax expression in the pathogenic yeast Candida albicans. Cell death inducing expression of Bax required a synthetic BAX gene that was codon-optimized for expression in Candida albicans. Expression of this BAX gene resulted in growth inhibition and cell death. By fusing Bax with the yeast enhanced green fluorescent protein of Aequoria victoria, the cell death-inducing effect of Bax was increased due to reduced proteolytic degradation of Bax. Using this fusion protein we showed that, upon expression in C. albicans, Bax co-localizes with the mitochondria. Furthermore, we showed for the first time that expression of Bax in yeast causes the mitochondria, which are normally distributed throughout the cell, to cluster in the perinuclear region. PMID:15565645

  10. External and internal triggers of cell death in yeast.

    PubMed

    Falcone, Claudio; Mazzoni, Cristina

    2016-06-01

    In recent years, yeast was confirmed as a useful eukaryotic model system to decipher the complex mechanisms and networks occurring in higher eukaryotes, particularly in mammalian cells, in physiological as well in pathological conditions. This article focuses attention on the contribution of yeast in the study of a very complex scenario, because of the number and interconnection of pathways, represented by cell death. Yeast, although it is a unicellular organism, possesses the basal machinery of different kinds of cell death occurring in higher eukaryotes, i.e., apoptosis, regulated necrosis and autophagy. Here we report the current knowledge concerning the yeast orthologs of main mammalian cell death regulators and executors, the role of organelles and compartments, and the cellular phenotypes observed in the different forms of cell death in response to external and internal triggers. Thanks to the ease of genetic manipulation of this microorganism, yeast strains expressing human genes that promote or counteract cell death, onset of tumors and neurodegenerative diseases have been constructed. The effects on yeast cells of some of these genes are also presented. PMID:27048816

  11. Many ways to die: passive and active cell death styles.

    PubMed

    Fietta, Pieranna

    2006-01-01

    In multicellular organisms, cells may undergo passive, pathological death in response to various environmental injuries, or actively decide to self-destroy in order to ensure proper physiological morphogenesis, preserve tissue homeostasis and eliminate abnormal cells. While the passive cell demise occurs in an accidental, violent and chaotic way, corresponding to "necrosis", the active auto-elimination, defined "programmed cell death" (PCD), is executed in planned modalities. Different PCD pathways have been described, such as apoptosis, autophagic death, para-apoptosis and programmed necrosis. However, death patterns may overlap or integrate, providing a variety of cellular responses to various circumstances or stimuli. The consequences for the whole organism of necrosis and PCD are quite different. In the case of classical necrosis, cytosolic constituents chaotically spill into extracellular space through damaged plasma membrane and provoke an inflammatory response, while in most PCDs the cellular components are safely isolated by membranes, and then consumed by adjacent parenchymal cells and/or resident phagocytes without inflammation. Thus, whereas the necrotic cell removal induces and amplifies pathological processes, the elimination of PCD debris may remain virtually unnoticed by the body. Otherwise, alterations of PCD controls may be involved in human diseases, such as developmental abnormalities, or neurodegenerative, autoimmune and neoplastic affections, whose treatment implies the complete understanding of cell suicide processes. In this review, the cellular death patterns are focused and their significance discussed. PMID:16791791

  12. Autosis and autophagic cell death: the dark side of autophagy

    PubMed Central

    Liu, Y; Levine, B

    2015-01-01

    It is controversial whether cells truly die via autophagy or whether — in dying cells — autophagy is merely an innocent bystander or a well-intentioned ‘Good Samaritan' trying to prevent inevitable cellular demise. However, there is increasing evidence that the genetic machinery of autophagy may be essential for cell death in certain settings. We recently identified a novel form of autophagy gene-dependent cell death, termed autosis, which is mediated by the Na+,K+-ATPase pump and has unique morphological features. High levels of cellular autophagy, as occurs with treatment with autophagy-inducing peptides, starvation, or in vivo during certain types of ischemia, can trigger autosis. These findings provide insights into the mechanisms and strategies for prevention of cell death during extreme stress conditions. PMID:25257169

  13. Autosis and autophagic cell death: the dark side of autophagy.

    PubMed

    Liu, Y; Levine, B

    2015-03-01

    It is controversial whether cells truly die via autophagy or whether - in dying cells - autophagy is merely an innocent bystander or a well-intentioned 'Good Samaritan' trying to prevent inevitable cellular demise. However, there is increasing evidence that the genetic machinery of autophagy may be essential for cell death in certain settings. We recently identified a novel form of autophagy gene-dependent cell death, termed autosis, which is mediated by the Na(+),K(+)-ATPase pump and has unique morphological features. High levels of cellular autophagy, as occurs with treatment with autophagy-inducing peptides, starvation, or in vivo during certain types of ischemia, can trigger autosis. These findings provide insights into the mechanisms and strategies for prevention of cell death during extreme stress conditions. PMID:25257169

  14. Modulation of cell death in age-related diseases.

    PubMed

    Tezil, Tugsan; Basaga, Huveyda

    2014-01-01

    Aging is a stage of life of all living organisms. According to the free-radical theory, aging cells gradually become unable to maintain cellular homeostasis due to the adverse effects of reactive oxygen species (ROS). ROS can cause irreversible DNA mutations, protein and lipid damage which are increasingly accumulated in the course of time if cells could not overcome these effects by the antioxidant defence system. Accrued damaged molecules in cells may either induce cellular death or contribute to develop various pathologies. Hence, programmed cell death mechanisms, apoptosis and autophagy, play a vital role in the aging process. Although they are strictly controlled by various interconnected signalling pathways, alterations in their regulations may contribute to severe pathologies including cancer, Alzheimer's and Parkinson's diseases. In this review, we summarized our current understanding and hypotheses regarding oxidative stress and age-related dysregulation of cell death signalling pathways. PMID:24079770

  15. Cell Death Mechanisms Induced by Cytotoxic Lymphocytes

    PubMed Central

    Chávez-Galán, L; Arenas-Del Angel, M C; Zenteno, E; Chávez, R; Lascurain, R

    2009-01-01

    One of the functions of the immune system is to recognize and destroy abnormal or infected cells to maintain homeostasis. This is accomplished by cytotoxic lymphocytes. Cytotoxicity is a highly organized multifactor process. Here, we reviewed the apoptosis pathways induced by the two main cytotoxic lymphocyte subsets, natural killer (NK) cells and CD8+ T cells. In base to recent experimental evidence, we reviewed NK receptors involved in recognition of target-cell, as well as lytic molecules such as perforin, granzymes-A and -B, and granulysin. In addition, we reviewed the Fas-FasL intercellular linkage mediated pathway, and briefly the cross-linking of tumor necrosis factor (TNF) and TNF receptor pathway. We discussed three models of possible molecular interaction between lytic molecules from effector cytotoxic cells and target-cell membrane to induction of apoptosis. PMID:19254476

  16. Therapeutic approaches to preventing cell death in Huntington disease

    PubMed Central

    Kaplan, Anna; Stockwell, Brent R.

    2012-01-01

    Neurodegenerative diseases affect the lives of millions of patients and their families. Due to the complexity of these diseases and our limited understanding of their pathogenesis, the design of therapeutic agents that can effectively treat these diseases has been challenging. Huntington disease (HD) is one of several neurological disorders with few therapeutic options. HD, like numerous other neurodegenerative diseases, involves extensive neuronal cell loss. One potential strategy to combat HD and other neurodegenerative disorders is to intervene in the execution of neuronal cell death. Inhibiting neuronal cell death pathways may slow the development of neurodegeneration. However, discovering small molecule inhibitors of neuronal cell death remains a significant challenge. Here, we review candidate therapeutic targets controlling cell death mechanisms that have been the focus of research in HD, as well as an emerging strategy that has been applied to developing small molecule inhibitors—fragment-based drug discovery (FBDD). FBDD has been successfully used in both industry and academia to identify selective and potent small molecule inhibitors, with a focus on challenging proteins that are not amenable to traditional high-throughput screening approaches. FBDD has been used to generate potent leads, pre-clinical candidates, and has led to the development of an FDA approved drug. This approach can be valuable for identifying modulators of cell-death-regulating proteins; such compounds may prove to be the key to halting the progression of HD and other neurodegenerative disorders. PMID:22967354

  17. Therapeutic approaches to preventing cell death in Huntington disease.

    PubMed

    Kaplan, Anna; Stockwell, Brent R

    2012-12-01

    Neurodegenerative diseases affect the lives of millions of patients and their families. Due to the complexity of these diseases and our limited understanding of their pathogenesis, the design of therapeutic agents that can effectively treat these diseases has been challenging. Huntington disease (HD) is one of several neurological disorders with few therapeutic options. HD, like numerous other neurodegenerative diseases, involves extensive neuronal cell loss. One potential strategy to combat HD and other neurodegenerative disorders is to intervene in the execution of neuronal cell death. Inhibiting neuronal cell death pathways may slow the development of neurodegeneration. However, discovering small molecule inhibitors of neuronal cell death remains a significant challenge. Here, we review candidate therapeutic targets controlling cell death mechanisms that have been the focus of research in HD, as well as an emerging strategy that has been applied to developing small molecule inhibitors-fragment-based drug discovery (FBDD). FBDD has been successfully used in both industry and academia to identify selective and potent small molecule inhibitors, with a focus on challenging proteins that are not amenable to traditional high-throughput screening approaches. FBDD has been used to generate potent leads, pre-clinical candidates, and has led to the development of an FDA approved drug. This approach can be valuable for identifying modulators of cell-death-regulating proteins; such compounds may prove to be the key to halting the progression of HD and other neurodegenerative disorders. PMID:22967354

  18. Microenvironmental Effects of Cell Death in Malignant Disease.

    PubMed

    Gregory, Christopher D; Ford, Catriona A; Voss, Jorine J L P

    2016-01-01

    Although apoptosis is well recognized as a cell death program with clear anticancer roles, accumulating evidence linking apoptosis with tissue repair and regeneration indicates that its relationship with malignant disease is more complex than previously thought. Here we review how the responses of neighboring cells in the microenvironment of apoptotic tumor cells may contribute to the cell birth/cell death disequilibrium that provides the basis for cancerous tissue emergence and growth. We describe the bioactive properties of apoptotic cells and consider, in particular, how apoptosis of tumor cells can engender a range of responses including pro-oncogenic signals having proliferative, angiogenic, reparatory, and immunosuppressive features. Drawing on the parallels between wound healing, tissue regeneration and cancer, we propose the concept of the "onco-regenerative niche," a cell death-driven generic network of tissue repair and regenerative mechanisms that are hijacked in cancer. Finally, we consider how the responses to cell death in tumors can be targeted to provide more effective and long-lasting therapies. PMID:27558817

  19. Lung epithelial cell death induced by oil-dispersant mixtures.

    PubMed

    Wang, He; Shi, Yongli; Major, Danielle; Yang, Zhanjun

    2012-08-01

    The dispersants used in oil spill disasters are claimed to be safe, but increased solubility of high-molecular-weight components in crude oil is of public health concern. The water-accommodated fractions (WAF) of crude oil mixed with dispersants may become airborne and cause lung epithelial damage when inhaled. This study was designed to examine the cell death and related death pathways of lung epithelial cells in response to WAF. Cultured A549 cells were treated for 2 or 24h with different concentrations of WAF. The WAF was prepared by mixing each of the dispersants (Corexit EC9527A, Corexit EC9500A and Corexit EC9580A) with crude oil for extraction with PBS. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide MTT assay, lactate dehydrogenase assay, morphology and cleaved caspase 9 protein, and microtubule-associated protein 1 light chain 3 were all used to measure cell viability, necrosis, apoptosis and autophagy quantitation, respectively. Results showed that the WAF of oil-dispersant mixtures caused cell death in the lung epithelial cells, in a dose-dependent manner, with the major cellular pathways of necrosis and apoptosis involved. Autophagy also occurred in cells exposed to WAF mixtures at lower concentrations before any detectable cell death, indicating greater sensitivity to WAF exposure. The three types of cell behavior, namely necrosis, apoptosis and autophagy, may play different roles in oil spill-related respiratory disorders. PMID:22504303

  20. Solamargine triggers hepatoma cell death through apoptosis

    PubMed Central

    XIE, XIAODONG; ZHU, HAITAO; YANG, HUIJIAN; HUANG, WENSI; WU, YINGYING; WANG, YING; LUO, YANLING; WANG, DONGQING; SHAO, GENBAO

    2015-01-01

    Solamargine (SM), a steroidal alkaloid glycoside extracted from the traditional Chinese herb Solanum incanum, has been evidenced to inhibit the growth and induce apoptosis in a number of human cancer cell lines. In the present study, the anticancer effect of SM and underlying molecular mechanism of SM-induced apoptosis were investigated on the human hepatocellular carcinoma cells, SMMC7721 and HepG2. The proliferation effects of SM on the SMMC7721 and HepG2 cell lines were evaluated using MTT and colony formation assays. In addition, the percentage of apoptosis was measured using an Annexin V/propidium iodide staining method and the cell cycle distribution mediated by SM was analyzed using flow cytometry. The expression levels of B-cell lymphoma-2 (Bcl-2), Bcl-2-associated X protein (Bax), caspase-3, caspase-9, proliferating cell nuclear antigen (pcna) and Ki67 proteins were examined to further demonstrate the proliferate and apoptosis effects of SM on the hepatoma cells. The results indicated that SM effectively inhibited hepatoma cell proliferation and promoted apoptosis. SM resulted in cell cycle arrest at the G2/M phase in the two cell lines. In addition, SM downregulated the levels of proliferation-associated (Ki67 and pcna) and anti-apoptotic (Bcl-2) proteins, and promoted the activity of apoptosis-associated proteins (Bax, caspase-3 and caspase-9). Therefore, the activation of the Bcl-2/Bax and caspase signaling pathways may be involved in the SM-induced apoptosis of hepatoma cells. PMID:26170994

  1. Systems Approaches to Preventing Transplanted Cell Death in Cardiac Repair

    PubMed Central

    Robey, Thomas E.; Saiget, Mark K; Reinecke, Hans; Murry, Charles E.

    2008-01-01

    Stem cell transplantation may repair the injured heart, but tissue regeneration is limited by death of transplanted cells. Most cell death occurs in the first few days post-transplantation, likely from a combination of ischemia, anoikis and inflammation. Interventions known to enhance transplanted cell survival include heat shock, over-expressing anti-apoptotic proteins, free radical scavengers, anti-inflammatory therapy and co-delivery of extracellular matrix molecules. Combinatorial use of such interventions markedly enhances graft cell survival, but death still remains a significant problem. We review these challenges to cardiac cell transplantation and present an approach to systematically address them. Most anti-death studies use histology to assess engraftment, which is time- and labor-intensive. To increase throughput, we developed two biochemical approaches to follow graft viability in the mouse heart. The first relies on LacZ enyzmatic activity to track genetically modified cells, and the second quantifies human genomic DNA content using repetitive Alu sequences. Both show linear relationships between input cell number and biochemical signal, but require correction for the time lag between cell death and loss of signal. Once optimized, they permit detection of as few as 1 graft cell in 40,000 host cells. Pro-survival effects measured biochemically at three days predict long-term histological engraftment benefits. These methods permitted identification of carbamylated erythropoietin (CEPO) as a pro-survival factor for human embryonic stem cell-derived cardiomyocyte grafts. CEPO’s effects were additive to heat shock, implying independent survival pathways. This system should permit combinatorial approaches to enhance graft viability in a fraction of the time required for conventional histology. PMID:18466917

  2. Detection of Apoptotic Versus Autophagic Cell Death by Flow Cytometry.

    PubMed

    Sica, Valentina; Maiuri, M Chiara; Kroemer, Guido; Galluzzi, Lorenzo

    2016-01-01

    Different modes of regulated cell death (RCD) can be initiated by distinct molecular machineries and their morphological manifestations can be difficult to discriminate. Moreover, cells responding to stress often activate an adaptive response centered around autophagy, and whether such a response is cytoprotective or cytotoxic cannot be predicted based on morphological parameters only. Molecular definitions are therefore important to understand various RCD subroutines from a mechanistic perspective. In vitro, various forms of RCD including apoptosis and autophagic cell death can be easily discriminated from each other with assays that involve chemical or pharmacological interventions targeting key components of either pathway. Here, we detail a straightforward method to discriminate apoptosis from autophagic cell death by flow cytometry, based on the broad-spectrum caspase inhibitor Z-VAD-fmk and the genetic inhibition of ATG5. PMID:27108427

  3. Porcine circovirus-2 capsid protein induces cell death in PK15 cells

    SciTech Connect

    Walia, Rupali; Dardari, Rkia Chaiyakul, Mark; Czub, Markus

    2014-11-15

    Studies have shown that Porcine circovirus (PCV)-2 induces apoptosis in PK15 cells. Here we report that cell death is induced in PCV2b-infected PK15 cells that express Capsid (Cap) protein and this effect is enhanced in interferon gamma (IFN-γ)-treated cells. We further show that transient PCV2a and 2b-Cap protein expression induces cell death in PK15 cells at rate similar to PCV2 infection, regardless of Cap protein localization. These data suggest that Cap protein may have the capacity to trigger different signaling pathways involved in cell death. Although further investigation is needed to gain deeper insights into the nature of the pathways involved in Cap-induced cell death, this study provides evidence that PCV2-induced cell death in kidney epithelial PK15 cells can be mapped to the Cap protein and establishes the need for future research regarding the role of Cap-induced cell death in PCV2 pathogenesis. - Highlights: • IFN-γ enhances PCV2 replication that leads to cell death in PK15 cells. • IFN-γ enhances nuclear localization of the PCV2 Capsid protein. • Transient PCV2a and 2b-Capsid protein expression induces cell death. • Cell death is not dictated by specific Capsid protein sub-localization.

  4. Metabolic flux ratio analysis and multi-objective optimization revealed a globally conserved and coordinated metabolic response of E. coli to paraquat-induced oxidative stress.

    PubMed

    Shen, Tie; Rui, Bin; Zhou, Hong; Zhang, Ximing; Yi, Yin; Wen, Han; Zheng, Haoran; Wu, Jihui; Shi, Yunyu

    2013-01-27

    . coli to paraquat-induced oxidative stress is globally conserved and coordinated. PMID:23128557

  5. X-ray-induced cell death: Apoptosis and necrosis

    SciTech Connect

    Nakano, Hisako; Shinohara, Kunio

    1994-10-01

    X-ray-induced cell death in MOLT-4N1, a subclone of MOLT-4 cells, and M10 cells was studied with respect to their modes of cell death, apoptosis and necrosis. MOLT-4N1 cells showed radiosensitivity similar to that of M10 cells, a radiosensitive mutant of L5178Y, as determined by the colony formation assay. Analysis of cell size demonstrated that MOLT-4N1 cells increased in size at an early stage after irradiation and then decreased to a size smaller than that of control cells, whereas the size of irradiated M10 cells increased continuously. Apoptosis detected by morphological changes and DNA ladder formation (the cleavage of DNA into oligonucleosomal fragments) occurred in X-irradiated MOLT-4N1 cells but not in M10 cells. Pulsed-field gel electrophoresis showed that the ladder formation involved an intermediate-sized DNA (about 20 kbp). Most of the DNA was detected at the origin in both methods of electrophoresis in the case of M10 cells, though a trace amount of ladder formation was observed. Heat treatment of M10 cells induced apoptosis within 30 min after treatment, in contrast to MOLT-4N1 cells. The results suggest that apoptosis and necrosis are induced by X rays in a manner which is dependent on the cell line irrespective of the capability of the cells to develop apoptosis. DNA fragmentation was the earliest change observed in the development of apoptosis. 27 refs., 8 figs., 1 tab.

  6. Non-apoptotic cell death associated with perturbations of macropinocytosis

    PubMed Central

    Maltese, William A.; Overmeyer, Jean H.

    2015-01-01

    Although macropinocytosis is widely recognized as a distinct form of fluid-phase endocytosis in antigen-presenting dendritic cells, it also occurs constitutively in many other normal and transformed cell types. Recent studies have established that various genetic or pharmacological manipulations can hyperstimulate macropinocytosis or disrupt normal macropinosome trafficking pathways, leading to accumulation of greatly enlarged cytoplasmic vacuoles. In some cases, this extreme vacuolization is associated with a unique form of non-apoptotic cell death termed “methuosis,” from the Greek methuo (to drink to intoxication). It remains unclear whether cell death related to dysfunctional macropinocytosis occurs in normal physiological contexts. However, the finding that some types of cancer cells are particularly vulnerable to this unusual form of cell death has raised the possibility that small molecules capable of altering macropinosome trafficking or function might be useful as therapeutic agents against cancers that are resistant to drugs that work by inducing apoptosis. Herein we review examples of cell death associated with dysfunctional macropinocytosis and summarize what is known about the underlying mechanisms. PMID:25762935

  7. Formation and Implications of Alpha-Synuclein Radical in Maneb- and Paraquat-Induced Models of Parkinson's Disease.

    PubMed

    Kumar, Ashutosh; Leinisch, Fabian; Kadiiska, Maria B; Corbett, Jean; Mason, Ronald P

    2016-07-01

    Parkinson's disease (PD) is a debilitating, progressive, neurodegenerative disorder characterized by progressive loss of dopaminergic neurons and motor deficits. Alpha-synuclein-containing aggregates represent a feature of a variety of neurodegenerative disorders, including PD; however, the mechanism that initiates and promotes intraneuronal alpha-synuclein aggregation remains unknown. We hypothesized protein radical formation as an initiating mechanism for alpha-synuclein aggregation. Therefore, we used the highly sensitive immuno-spin trapping technique to investigate protein radical formation as a possible mechanism of alpha-synuclein aggregation as well as to investigate the source of protein radical formation in the midbrains of Maneb- and paraquat-coexposed mice. Coexposure to Maneb and paraquat for 6 weeks resulted in active microgliosis, NADPH oxidase activation, and inducible nitric oxide synthase (iNOS) induction, which culminated in protein radical formation in the midbrains of mice. Results obtained with immuno-spin trapping and immunoprecipitation experiments confirmed formation of alpha-synuclein radicals in dopaminergic neurons of exposed mice. Free radical formation requires NADPH oxidase and iNOS, as indicated by decreased protein radical formation in knockout mice (P47phox(-/-) and iNOS(-/-)) and in mice treated with inhibitors such as FeTPPS (a peroxynitrite decomposition catalyst), 1400 W (an iNOS inhibitor), or apocynin (a NADPH oxidase inhibitor). Concurrence of protein radical formation with dopaminergic neuronal death indicated a link between protein radicals and disease progression. Taken together, these results show for the first time the formation and detection of the alpha-synuclein radical and suggest that NADPH oxidase and iNOS play roles in peroxynitrite-mediated protein radical formation and subsequent neuronal death in the midbrains of Maneb- and paraquat-coexposed mice. PMID:25952542

  8. Glycobiology of cell death: when glycans and lectins govern cell fate

    PubMed Central

    Lichtenstein, R G; Rabinovich, G A

    2013-01-01

    Although one typically thinks of carbohydrates as associated with cell growth and viability, glycosylation also has an integral role in many processes leading to cell death. Glycans, either alone or complexed with glycan-binding proteins, can deliver intracellular signals or control extracellular processes that promote initiation, execution and resolution of cell death programs. Herein, we review the role of glycans and glycan-binding proteins as essential components of the cell death machinery during physiologic and pathologic settings. PMID:23703323

  9. Oxidative Stress and Programmed Cell Death in Yeast

    PubMed Central

    Farrugia, Gianluca; Balzan, Rena

    2012-01-01

    Yeasts, such as Saccharomyces cerevisiae, have long served as useful models for the study of oxidative stress, an event associated with cell death and severe human pathologies. This review will discuss oxidative stress in yeast, in terms of sources of reactive oxygen species (ROS), their molecular targets, and the metabolic responses elicited by cellular ROS accumulation. Responses of yeast to accumulated ROS include upregulation of antioxidants mediated by complex transcriptional changes, activation of pro-survival pathways such as mitophagy, and programmed cell death (PCD) which, apart from apoptosis, includes pathways such as autophagy and necrosis, a form of cell death long considered accidental and uncoordinated. The role of ROS in yeast aging will also be discussed. PMID:22737670

  10. Motoneuron Programmed Cell Death in Response to proBDNF

    PubMed Central

    Taylor, AR; Gifondorwa, DJ; Robinson, MB; Strupe, JL; Prevette, D; Johnson, JE; Hempstead, BL; Oppenheim, RW; Milligan, CE

    2011-01-01

    Motoneurons (MN) as well as most neuronal populations undergo a temporally and spatially specific period of programmed cell death (PCD). Several factors have been considered to regulate the survival of MNs during this period, including availability of muscle-derived trophic support and activity. The possibility that target-derived factors may also negatively regulate MN survival has been considered, but not pursued. Neurotrophin precursors, through their interaction with p75NTR and sortilin receptors have been shown to induce cell death during development and following injury in the CNS. In this study, we find that muscle cells produce and secrete proBDNF. ProBDNF through its interaction with p75NTR and sortilin, promotes a caspase-dependent death of MNs in culture. We also provide data to suggest that proBDNF regulates MN PCD during development in vivo. PMID:21834083

  11. How does metabolism affect cell death in cancer?

    PubMed

    Villa, Elodie; Ricci, Jean-Ehrland

    2016-07-01

    In cancer research, identifying a specificity of tumor cells compared with 'normal' proliferating cells for targeted therapy is often considered the Holy Grail for researchers and clinicians. Although diverse in origin, most cancer cells share characteristics including the ability to escape cell death mechanisms and the utilization of different methods of energy production. In the current paradigm, aerobic glycolysis is considered the central metabolic characteristic of cancer cells (Warburg effect). However, recent data indicate that cancer cells also show significant changes in other metabolic pathways. Indeed, it was recently suggested that Kreb's cycle, pentose phosphate pathway intermediates, and essential and nonessential amino acids have key roles. Renewed interest in the fact that cancer cells have to reprogram their metabolism in order to proliferate or resist treatment must take into consideration the ability of tumor cells to adapt their metabolism to the local microenvironment (low oxygen, low nutrients). This variety of metabolic sources might be either a strength, resulting in infinite possibilities for adaptation and increased ability to resist chemotherapy-induced death, or a weakness that could be targeted to kill cancer cells. Here, we discuss recent insights showing how energetic metabolism may regulate cell death and how this might be relevant for cancer treatment. PMID:26498911

  12. Programmed Cell Death During Female Gametophyte Development

    SciTech Connect

    Drews, Gary, N.

    2004-09-15

    Endosperm is a storage tissue in the angiosperm seed that is important both biologically and agriculturally. Endosperm is biologically important because it provides nutrients to the embryo during seed development and agriculturally important because it is a significant source of food, feed, and industrial raw materials. Approximately two-thirds of human calories are derived from endosperm, either directly or indirectly through animal feed. Furthermore, endosperm is used as a raw material for numerous industrial products including ethanol. A major event in endosperm development is the transition between the syncytial phase, during which the endosperm nuclei undergo many rounds of mitosis without cytokinesis, and the cellularized phase, during which cell walls form around the endosperm nuclei. Understanding how the syncytial-cellular transition is regulated is agriculturally important because it influences seed size, seed sink strength, and grain weight. However, the molecular processes controlling this transition are not understood. This project led to the identification of the AGL62 gene that regulates the syncytial-cellular transition during endosperm development. AGL62 is expressed during the syncytial phase and suppresses endosperm cellularization during this period. AGL62 most likely does so by suppressing the expression of genes required for cellularization. At the end of the syncytial phase, the FIS PcG complex suppresses AGL62 expression, which allows expression of the cellularization genes and triggers the initiation of the cellularized phase. Endosperm arises following fertilization of the central cell within the female gametophyte. This project also led to the identification of the AGL80 gene that is required for development of the central cell into the endosperm. Within the ovule and seed, AGL80 is expressed exclusively in the central cell and uncellularized endosperm. AGL80 is required for expression of several central cell-expressed genes, including

  13. Role of mitochondria on muscle cell death and meat tenderization.

    PubMed

    Sierra, Verónica; Oliván, Mamen

    2013-05-01

    The possibility that mitochondria are involved in cellular dysfunction is particularly high in situations associated with increases in free radical activity, like hypoxia or ischemia; therefore its potential role in the muscle post-mortem metabolism is reviewed. In the dying muscle, different routes of cell death catabolism (apoptosis, autophagy) may occur having great influence on the process of conversion of muscle into meat. Mitochondria are the first and also one of the main organelles affected by post-mortem changes; therefore they are decisive in the subsequent cellular responses influencing the pathway to cell demise and thus, the final meat quality. Depending on the cell death programme followed by muscle cells after exsanguination, diverse proteases would be activated to a different extent, which is also reviewed in order to understand how they affect meat tenderization. This review also summarizes recent patents relating cell death processes and meat tenderness. Further research is encouraged as there is still a need of knowledge on cell death post-mortem processes to increase our understanding of the conversion of muscle into meat. PMID:23432120

  14. Sensory hair cell death and regeneration in fishes

    PubMed Central

    Monroe, Jerry D.; Rajadinakaran, Gopinath; Smith, Michael E.

    2015-01-01

    Sensory hair cells are specialized mechanotransductive receptors required for hearing and vestibular function. Loss of hair cells in humans and other mammals is permanent and causes reduced hearing and balance. In the early 1980’s, it was shown that hair cells continue to be added to the inner ear sensory epithelia in cartilaginous and bony fishes. Soon thereafter, hair cell regeneration was documented in the chick cochlea following acoustic trauma. Since then, research using chick and other avian models has led to great insights into hair cell death and regeneration. However, with the rise of the zebrafish as a model organism for studying disease and developmental processes, there has been an increased interest in studying sensory hair cell death and regeneration in its lateral line and inner ears. Advances derived from studies in zebrafish and other fish species include understanding the effect of ototoxins on hair cells and finding otoprotectants to mitigate ototoxin damage, the role of cellular proliferation vs. direct transdifferentiation during hair cell regeneration, and elucidating cellular pathways involved in the regeneration process. This review will summarize research on hair cell death and regeneration using fish models, indicate the potential strengths and weaknesses of these models, and discuss several emerging areas of future studies. PMID:25954154

  15. The Arabidopsis peptide kiss of death is an inducer of programmed cell death

    PubMed Central

    Blanvillain, Robert; Young, Bennett; Cai, Yao-min; Hecht, Valérie; Varoquaux, Fabrice; Delorme, Valérie; Lancelin, Jean-Marc; Delseny, Michel; Gallois, Patrick

    2011-01-01

    Programmed cell death (PCD) has a key role in defence and development of all multicellular organisms. In plants, there is a large gap in our knowledge of the molecular machinery involved at the various stages of PCD, especially the early steps. Here, we identify kiss of death (KOD) encoding a 25-amino-acid peptide that activates a PCD pathway in Arabidopsis thaliana. Two mutant alleles of KOD exhibited a reduced PCD of the suspensor, a single file of cells that support embryo development, and a reduced PCD of root hairs after a 55°C heat shock. KOD expression was found to be inducible by biotic and abiotic stresses. Furthermore, KOD expression was sufficient to cause death in leaves or seedlings and to activate caspase-like activities. In addition, KOD-induced PCD required light in leaves and was repressed by the PCD-suppressor genes AtBax inhibitor 1 and p35. KOD expression resulted in depolarization of the mitochondrial membrane, placing KOD above mitochondria dysfunction, an early step in plant PCD. A KOD∷GFP fusion, however, localized in the cytosol of cells and not mitochondria. PMID:21326210

  16. Regulation of Ferroptotic Cancer Cell Death by GPX4

    PubMed Central

    Welsch, Matthew E.; Shimada, Kenichi; Skouta, Rachid; Viswanathan, Vasanthi S.; Cheah, Jaime H.; Clemons, Paul A.; Shamji, Alykhan F.; Clish, Clary B.; Brown, Lewis M.; Girotti, Albert W.; Cornish, Virginia W.; Schreiber, Stuart L.; Stockwell, Brent R.

    2014-01-01

    SUMMARY Ferroptosis is a form of nonapoptotic cell death for which key regulators remain unknown. We sought a common mediator for the lethality of 12 ferroptosisinducing small molecules. We used targeted metabolomic profiling to discover that depletion of glutathione causes inactivation of glutathione peroxidases (GPXs) in response to one class of compounds and a chemoproteomics strategy to discover that GPX4 is directly inhibited by a second class of compounds. GPX4 overexpression and knockdown modulated the lethality of 12 ferroptosis inducers, but not of 11 compounds with other lethal mechanisms. In addition, two representative ferroptosis inducers prevented tumor growth in xenograft mouse tumor models. Sensitivity profiling in 177 cancer cell lines revealed that diffuse large B cell lymphomas and renal cell carcinomas are particularly susceptible to GPX4-regulated ferroptosis. Thus, GPX4 is an essential regulator of ferroptotic cancer cell death. PMID:24439385

  17. CSR1 induces cell death through inactivation of CPSF3.

    PubMed

    Zhu, Z-H; Yu, Y P; Shi, Y-K; Nelson, J B; Luo, J-H

    2009-01-01

    CSR1 (cellular stress response 1), a newly characterized tumor-suppressor gene, undergoes hypermethylation in over 30% of prostate cancers. Re-expression of CSR1 inhibits cell growth and induces cell death, but the mechanism by which CSR1 suppresses tumor growth is not clear. In this study, we screened a prostate cDNA library using a yeast two-hybrid system and found that the cleavage and polyadenylation-specific factor 3 (CPSF3), an essential component for converting heteronuclear RNA to mRNA, binds with high affinity to the CSR1 C terminus. Further analyses determined that the binding motifs for CPSF3 are located between amino acids 440 and 543. The interaction between CSR1 and CPSF3 induced CPSF3 translocation from the nucleus to the cytoplasm, resulting in inhibition of polyadenylation both in vitro and in vivo. Downregulation of CPSF3 using small interfering RNA induced cell death in a manner similar to CSR1 expression. A CSR1 mutant unable to bind to CPSF3 did not alter CPSF3 subcellular distribution, did not inhibit its polyadenylation activity and did not induce cell death. In summary, CSR1 appears to induce cell death through a novel mechanism by hijacking a critical RNA processing enzyme. PMID:18806823

  18. Hydrogen Peroxide Produced by Oral Streptococci Induces Macrophage Cell Death

    PubMed Central

    Okahashi, Nobuo; Nakata, Masanobu; Sumitomo, Tomoko; Terao, Yutaka; Kawabata, Shigetada

    2013-01-01

    Hydrogen peroxide (H2O2) produced by members of the mitis group of oral streptococci plays important roles in microbial communities such as oral biofilms. Although the cytotoxicity of H2O2 has been widely recognized, the effects of H2O2 produced by oral streptococci on host defense systems remain unknown. In the present study, we investigated the effect of H2O2 produced by Streptococcus oralis on human macrophage cell death. Infection by S. oralis was found to stimulate cell death of a THP-1 human macrophage cell line at multiplicities of infection greater than 100. Catalase, an enzyme that catalyzes the decomposition of H2O2, inhibited the cytotoxic effect of S. oralis. S. oralis deletion mutants lacking the spxB gene, which encodes pyruvate oxidase, and are therefore deficient in H2O2 production, showed reduced cytotoxicity toward THP-1 macrophages. Furthermore, H2O2 alone was capable of inducing cell death. The cytotoxic effect seemed to be independent of inflammatory responses, because H2O2 was not a potent stimulator of tumor necrosis factor-α production in macrophages. These results indicate that streptococcal H2O2 plays a role as a cytotoxin, and is implicated in the cell death of infected human macrophages. PMID:23658745

  19. Lipid raft involvement in yeast cell growth and death

    PubMed Central

    Mollinedo, Faustino

    2012-01-01

    The notion that cellular membranes contain distinct microdomains, acting as scaffolds for signal transduction processes, has gained considerable momentum. In particular, a class of such domains that is rich in sphingolipids and cholesterol, termed as lipid rafts, is thought to compartmentalize the plasma membrane, and to have important roles in survival and cell death signaling in mammalian cells. Likewise, yeast lipid rafts are membrane domains enriched in sphingolipids and ergosterol, the yeast counterpart of mammalian cholesterol. Sterol-rich membrane domains have been identified in several fungal species, including the budding yeast Saccharomyces cerevisiae, the fission yeast Schizosaccharomyces pombe as well as the pathogens Candida albicans and Cryptococcus neoformans. Yeast rafts have been mainly involved in membrane trafficking, but increasing evidence implicates rafts in a wide range of additional cellular processes. Yeast lipid rafts house biologically important proteins involved in the proper function of yeast, such as proteins that control Na+, K+, and pH homeostasis, which influence many cellular processes, including cell growth and death. Membrane raft constituents affect drug susceptibility, and drugs interacting with sterols alter raft composition and membrane integrity, leading to yeast cell death. Because of the genetic tractability of yeast, analysis of yeast rafts could be an excellent model to approach unanswered questions of mammalian raft biology, and to understand the role of lipid rafts in the regulation of cell death and survival in human cells. A better insight in raft biology might lead to envisage new raft-mediated approaches to the treatment of human diseases where regulation of cell death and survival is critical, such as cancer and neurodegenerative diseases. PMID:23087902

  20. Autophagonizer, a novel synthetic small molecule, induces autophagic cell death

    SciTech Connect

    Choi, In-Kwon; Cho, Yoon Sun; Jung, Hye Jin; Kwon, Ho Jeong

    2010-03-19

    Autophagy is an apoptosis-independent mechanism of cell death that protects the cell from environmental imbalances and infection by pathogens. We identified a novel small molecule, 2-(3-Benzyl-4-oxo-3,4,5,6,7,8-hexahydro-benzo[4,5]thieno[2,3-d] pyrimidin-2-ylsulfanylmethyl)-oxazole-4-carboxylic acid (2-pyrrolidin-1-yl-ethyl)-amide (referred as autophagonizer), using high-content cell-based screening and the autophagosome marker EGFP-LC3. Autophagonizer inhibited growth and induced cell death in the human tumor cell lines MCF7, HeLa, HCT116, A549, AGS, and HT1080 via a caspase-independent pathway. Conversion of cytosolic LC3-I to autophagosome-associated LC3-II was greatly enhanced by autophagonizer treatment. Transmission electron microscopy and acridine orange staining revealed increased autophagy in the cytoplasm of autophagonizer-treated cells. In conclusion, autophagonizer is a novel autophagy inducer with unique structure, which induces autophagic cell death in the human tumor cell lines.

  1. Ghrelin Inhibits Oligodendrocyte Cell Death by Attenuating Microglial Activation

    PubMed Central

    Lee, Jee Youn

    2014-01-01

    Background Recently, we reported the antiapoptotic effect of ghrelin in spinal cord injury-induced apoptotic cell death of oligodendrocytes. However, how ghrelin inhibits oligodendrocytes apoptosis, is still unknown. Therefore, in the present study, we examined whether ghrelin inhibits microglia activation and thereby inhibits oligodendrocyte apoptosis. Methods Using total cell extracts prepared from BV-2 cells activated by lipopolysaccharide (LPS) with or without ghrelin, the levels of p-p38 phosphor-p38 mitogen-activated protein kinase (p-p38MAPK), phospho-c-Jun N-terminal kinase (pJNK), p-c-Jun, and pro-nerve growth factor (proNGF) were examined by Western blot analysis. Reactive oxygen species (ROS) production was investigated by using dichlorodihydrofluorescein diacetate. To examine the effect of ghrelin on oligodendrocyte cell death, oligodendrocytes were cocultured in transwell chambers of 24-well plates with LPS-stimulated BV-2 cells. After 48 hours incubation, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and terminal deoxynucleotidyl transferase 2'-deoxyuridine, 5'-triphosphate nick end labeling staining were assessed. Results Ghrelin treatment significantly decreased levels of p-p38MAPK, p-JNK, p-c-Jun, and proNGF in LPS-stimulated BV-2 cells. ROS production increased in LPS-stimulated BV-2 cells was also significantly inhibited by ghrelin treatment. In addition, ghrelin significantly inhibited oligodendrocyte cell death when cocultured with LPS-stimulated BV-2 cells. Conclusion Ghrelin inhibits oligodendrocyte cell death by decreasing proNGF and ROS production as well as p38MAPK and JNK activation in activated microglia as an anti-inflammatory hormone. PMID:25309797

  2. Cytokine signaling for proliferation, survival, and death in hematopoietic cells.

    PubMed

    Miyajima, A; Ito, Y; Kinoshita, T

    1999-04-01

    The survival, proliferation, and differentiation of hematopoietic cells are regulated by cytokines. In the absence of cytokines, hematopoietic cells not only stop proliferation, but undergo apoptosis. This strict dependency of hematopoietic cells on cytokines is an important mechanism that maintains the homeostasis of blood cells. Cytokines induce various intracellular signaling pathways by activating the receptor-associated Janus kinases (Jaks), and distinct signals are responsible for cell cycle progression and cell survival. Induction of signals for cell cycle progression without suppressing apoptosis results in apoptotic cell death, indicating the essential role of anti-apoptotic signaling for cell growth. In hematopoietic cells, Ras, a cellular protooncogen product, and phosphatidylinositol 3 kinase are involved in the suppression of apoptosis. Cytokine depletion not only turns off anti-apoptotic signaling, but also actively induces cell death by activating caspases, a distinct family of cysteine proteases. Alterations in the mechanisms of cytokine signaling for cell cycle progression and anti-apoptotic function are implicated in hematological disorders. PMID:10222650

  3. Die another way – non-apoptotic mechanisms of cell death

    PubMed Central

    Tait, Stephen W. G.; Ichim, Gabriel; Green, Douglas R.

    2014-01-01

    ABSTRACT Regulated, programmed cell death is crucial for all multicellular organisms. Cell death is essential in many processes, including tissue sculpting during embryogenesis, development of the immune system and destruction of damaged cells. The best-studied form of programmed cell death is apoptosis, a process that requires activation of caspase proteases. Recently it has been appreciated that various non-apoptotic forms of cell death also exist, such as necroptosis and pyroptosis. These non-apoptotic cell death modalities can be either triggered independently of apoptosis or are engaged should apoptosis fail to execute. In this Commentary, we discuss several regulated non-apoptotic forms of cell death including necroptosis, autophagic cell death, pyroptosis and caspase-independent cell death. We outline what we know about their mechanism, potential roles in vivo and define outstanding questions. Finally, we review data arguing that the means by which a cell dies actually matters, focusing our discussion on inflammatory aspects of cell death. PMID:24833670

  4. Cell death monitoring using quantitative optical coherence tomography methods

    NASA Astrophysics Data System (ADS)

    Farhat, Golnaz; Yang, Victor X. D.; Kolios, Michael C.; Czarnota, Gregory J.

    2011-03-01

    Cell death is characterized by a series of predictable morphological changes, which modify the light scattering properties of cells. We present a multi-parametric approach to detecting changes in subcellular morphology related to cell death using optical coherence tomography (OCT). Optical coherence tomography data were acquired from acute myeloid leukemia (AML) cells undergoing apoptosis over a period of 48 hours. Integrated backscatter (IB) and spectral slope (SS) were computed from OCT backscatter spectra and statistical parameters were extracted from a generalized gamma (GG) distribution fit to OCT signal intensity histograms. The IB increased by 2-fold over 48 hours with significant increases observed as early as 4 hours. The SS increased in steepness by 2.5-fold with significant changes at 12 hours, while the GG parameters were sensitive to apoptotic changes at 24 to 48 hours. Histology slides indicated nuclear condensation and fragmentation at 24 hours, suggesting the late scattering changes could be related to nuclear structure. A second series of measurements from AML cells treated with cisplatin, colchicine or ionizing radiation suggested that the GG parameters could potentially differentiate between modes of cell death. Distinct cellular morphology was observed in histology slides obtained from cells treated under each condition.

  5. Mitochondrial and Cell Death Mechanisms in Neurodegenerative Diseases

    PubMed Central

    Martin, Lee J.

    2010-01-01

    Alzheimer’s disease (AD), Parkinson’s disease (PD) and amyotrophic lateral sclerosis (ALS) are the most common human adult-onset neurodegenerative diseases. They are characterized by prominent age-related neurodegeneration in selectively vulnerable neural systems. Some forms of AD, PD, and ALS are inherited, and genes causing these diseases have been identified. Nevertheless, the mechanisms of the neuronal cell death are unresolved. Morphological, biochemical, genetic, as well as cell and animal model studies reveal that mitochondria could have roles in this neurodegeneration. The functions and properties of mitochondria might render subsets of selectively vulnerable neurons intrinsically susceptible to cellular aging and stress and overlying genetic variations, triggering neurodegeneration according to a cell death matrix theory. In AD, alterations in enzymes involved in oxidative phosphorylation, oxidative damage, and mitochondrial binding of Aβ and amyloid precursor protein have been reported. In PD, mutations in putative mitochondrial proteins have been identified and mitochondrial DNA mutations have been found in neurons in the substantia nigra. In ALS, changes occur in mitochondrial respiratory chain enzymes and mitochondrial cell death proteins. Transgenic mouse models of human neurodegenerative disease are beginning to reveal possible principles governing the biology of selective neuronal vulnerability that implicate mitochondria and the mitochondrial permeability transition pore. This review summarizes how mitochondrial pathobiology might contribute to neuronal death in AD, PD, and ALS and could serve as a target for drug therapy. PMID:21258649

  6. Light uncages a copper complex to induce nonapoptotic cell death.

    PubMed

    Kumbhar, Anupa A; Franks, Andrew T; Butcher, Raymond J; Franz, Katherine J

    2013-03-25

    Cu3G is a Cu(II) complex of a photoactive tetradentate ligand that is cleaved upon UV irradiation to release Cu. Here we show that the cytotoxicity of Cu3G increases in response to brief UV stimulation to result in extensive cytoplasmic vacuolization that is indicative of nonapoptotic cell death. PMID:23417227

  7. Bortezomib induces autophagic death in proliferating human endothelial cells

    SciTech Connect

    Belloni, Daniela; Veschini, Lorenzo; Foglieni, Chiara; Dell'Antonio, Giacomo; Caligaris-Cappio, Federico; Ferrarini, Marina; Ferrero, Elisabetta

    2010-04-01

    The proteasome inhibitor Bortezomib has been approved for the treatment of relapsed/refractory multiple myeloma (MM), thanks to its ability to induce MM cell apoptosis. Moreover, Bortezomib has antiangiogenic properties. We report that endothelial cells (EC) exposed to Bortezomib undergo death to an extent that depends strictly on their activation state. Indeed, while quiescent EC are resistant to Bortezomib, the drug results maximally toxic in EC switched toward angiogenesis with FGF, and exerts a moderate effect on subconfluent HUVEC. Moreover, EC activation state deeply influences the death pathway elicited by Bortezomib: after treatment, angiogenesis-triggered EC display typical features of apoptosis. Conversely, death of subconfluent EC is preceded by ROS generation and signs typical of autophagy, including intense cytoplasmic vacuolization with evidence of autophagosomes at electron microscopy, and conversion of the cytosolic MAP LC3 I form toward the autophagosome-associated LC3 II form. Treatment with the specific autophagy inhibitor 3-MA prevents both LC3 I/LC3 II conversion and HUVEC cell death. Finally, early removal of Bortezomib is accompanied by the recovery of cell shape and viability. These findings strongly suggest that Bortezomib induces either apoptosis or autophagy in EC; interfering with the autophagic response may potentiate the antiangiogenic effect of the drug.

  8. PROGRAMMED CELL DEATH IN EXTRAOCULAR MUSCLE TENDON/SCLERA PRECURSORS

    EPA Science Inventory

    Abstract

    Purpose: This study was designed to examine the occurrence of natural cell death in the periocular mesenchyme of mouse embryos.

    Methods: Vital staining with LysoTracker Red and Nile blue sulphate as well as terminal nick end labeling (TUNEL) were utiliz...

  9. Retinal Cell Death Caused by Sodium Iodate Involves Multiple Caspase-Dependent and Caspase-Independent Cell-Death Pathways

    PubMed Central

    Balmer, Jasmin; Zulliger, Rahel; Roberti, Stefano; Enzmann, Volker

    2015-01-01

    Herein, we have investigated retinal cell-death pathways in response to the retina toxin sodium iodate (NaIO3) both in vivo and in vitro. C57/BL6 mice were treated with a single intravenous injection of NaIO3 (35 mg/kg). Morphological changes in the retina post NaIO3 injection in comparison to untreated controls were assessed using electron microscopy. Cell death was determined by TdT-mediated dUTP-biotin nick end labeling (TUNEL) staining. The activation of caspases and calpain was measured using immunohistochemistry. Additionally, cytotoxicity and apoptosis in retinal pigment epithelial (RPE) cells, primary retinal cells, and the cone photoreceptor (PRC) cell line 661W were assessed in vitro after NaIO3 treatment using the ApoToxGlo™ assay. The 7-AAD/Annexin-V staining was performed and necrostatin (Nec-1) was administered to the NaIO3-treated cells to confirm the results. In vivo, degenerating RPE cells displayed a rounded shape and retracted microvilli, whereas PRCs featured apoptotic nuclei. Caspase and calpain activity was significantly upregulated in retinal sections and protein samples from NaIO3-treated animals. In vitro, NaIO3 induced necrosis in RPE cells and apoptosis in PRCs. Furthermore, Nec-1 significantly decreased NaIO3-induced RPE cell death, but had no rescue effect on treated PRCs. In summary, several different cell-death pathways are activated in retinal cells as a result of NaIO3. PMID:26151844

  10. Docosahexaenoic acid prevents paraquat-induced reactive oxygen species production in dopaminergic neurons via enhancement of glutathione homeostasis.

    PubMed

    Lee, Hyoung Jun; Han, Jeongsu; Jang, Yunseon; Kim, Soo Jeong; Park, Ji Hoon; Seo, Kang Sik; Jeong, Soyeon; Shin, Soyeon; Lim, Kyu; Heo, Jun Young; Kweon, Gi Ryang

    2015-01-30

    Omega-3 polyunsaturated fatty acid levels are reduced in the substantia nigra area in Parkinson's disease patients and animal models, implicating docosahexaenoic acid (DHA) as a potential treatment for preventing Parkinson's disease and suggesting the need for investigations into how DHA might protect against neurotoxin-induced dopaminergic neuron loss. The herbicide paraquat (PQ) induces dopaminergic neuron loss through the excessive production of reactive oxygen species (ROS). We found that treatment of dopaminergic SN4741 cells with PQ reduced cell viability in a dose-dependent manner, but pretreatment with DHA ameliorated the toxic effect of PQ. To determine the toxic mechanism of PQ, we measured intracellular ROS content in different organelles with specific dyes. As expected, all types of ROS were increased by PQ treatment, but DHA pretreatment selectively decreased cytosolic hydrogen peroxide content. Furthermore, DHA treatment-induced increases in glutathione reductase and glutamate cysteine ligase modifier subunit (GCLm) mRNA expression were positively correlated with glutathione (GSH) content. Consistent with this increase in GCLm mRNA levels, Western blot analysis revealed that DHA pretreatment increased nuclear factor-erythroid 2 related factor 2 (Nrf2) protein levels. These findings indicate that DHA prevents PQ-induced neuronal cell loss by enhancing Nrf2-regulated GSH homeostasis. PMID:25545062

  11. Connective tissue growth factor stimulates the proliferation, migration and differentiation of lung fibroblasts during paraquat-induced pulmonary fibrosis.

    PubMed

    Yang, Zhizhou; Sun, Zhaorui; Liu, Hongmei; Ren, Yi; Shao, Danbing; Zhang, Wei; Lin, Jinfeng; Wolfram, Joy; Wang, Feng; Nie, Shinan

    2015-07-01

    It is well established that paraquat (PQ) poisoning can cause severe lung injury during the early stages of exposure, finally leading to irreversible pulmonary fibrosis. Connective tissue growth factor (CTGF) is an essential growth factor that is involved in tissue repair and pulmonary fibrogenesis. In the present study, the role of CTGF was examined in a rat model of pulmonary fibrosis induced by PQ poisoning. Histological examination revealed interstitial edema and extensive cellular thickening of interalveolar septa at the early stages of poisoning. At 2 weeks after PQ administration, lung tissue sections exhibited a marked thickening of the alveolar walls with an accumulation of interstitial cells with a fibroblastic appearance. Masson's trichrome staining revealed a patchy distribution of collagen deposition, indicating pulmonary fibrogenesis. Western blot analysis and immunohistochemical staining of tissue samples demonstrated that CTGF expression was significantly upregulated in the PQ-treated group. Similarly, PQ treatment of MRC-5 human lung fibroblast cells caused an increase in CTGF in a dose-dependent manner. Furthermore, the addition of CTGF to MRC-5 cells triggered cellular proliferation and migration. In addition, CTGF induced the differentiation of fibroblasts to myofibroblasts, as was evident from increased expression of α-smooth muscle actin (α-SMA) and collagen. These findings demonstrate that PQ causes increased CTGF expression, which triggers proliferation, migration and differentiation of lung fibroblasts. Therefore, CTGF may be important in PQ-induced pulmonary fibrogenesis, rendering this growth factor a potential pharmacological target for reducing lung injury. PMID:25815693

  12. Targeting Mitochondria with Avocatin B Induces Selective Leukemia Cell Death.

    PubMed

    Lee, Eric A; Angka, Leonard; Rota, Sarah-Grace; Hanlon, Thomas; Mitchell, Andrew; Hurren, Rose; Wang, Xiao Ming; Gronda, Marcela; Boyaci, Ezel; Bojko, Barbara; Minden, Mark; Sriskanthadevan, Shrivani; Datti, Alessandro; Wrana, Jeffery L; Edginton, Andrea; Pawliszyn, Janusz; Joseph, Jamie W; Quadrilatero, Joe; Schimmer, Aaron D; Spagnuolo, Paul A

    2015-06-15

    Treatment regimens for acute myeloid leukemia (AML) continue to offer weak clinical outcomes. Through a high-throughput cell-based screen, we identified avocatin B, a lipid derived from avocado fruit, as a novel compound with cytotoxic activity in AML. Avocatin B reduced human primary AML cell viability without effect on normal peripheral blood stem cells. Functional stem cell assays demonstrated selectivity toward AML progenitor and stem cells without effects on normal hematopoietic stem cells. Mechanistic investigations indicated that cytotoxicity relied on mitochondrial localization, as cells lacking functional mitochondria or CPT1, the enzyme that facilitates mitochondria lipid transport, were insensitive to avocatin B. Furthermore, avocatin B inhibited fatty acid oxidation and decreased NADPH levels, resulting in ROS-dependent leukemia cell death characterized by the release of mitochondrial proteins, apoptosis-inducing factor, and cytochrome c. This study reveals a novel strategy for selective leukemia cell eradication based on a specific difference in mitochondrial function. PMID:26077472

  13. Metal-accelerated oxidation in plant cell death

    SciTech Connect

    Czuba, M. )

    1993-05-01

    Cadmium and mercury toxicity is further enhanced by external oxidizing conditions O[sub 3] or inherent plant processes. Lepidium sativum L, Lycopersicon esculentum Mill., or Phaseolus vulgaris L, were grown inpeat-lite to maturity under continuous cadmium exposure followed by one oxidant (O[sub 3]-6 hr. 30 pphm) exposure, with or without foliar calcium pretreatments. In comparison, Daucus carota, L and other species grown in a 71-V suspension, with or without 2,4-D were exposed continuously to low levels of methylmercury during exponential growth and analyzed in aggregates of distinct populations. Proteins were extracted and analyzed. Mechanisms of toxicity and eventual cell death are Ca-mediated and involve chloroplast, stomatal-water relations and changes in oxidant-anti-oxidant components in cells. Whether the metal-accelerated oxidative damage proceeds to cell death, depends on the species and its differential biotransformation system and cell association component.

  14. Autophagy and Tubular Cell Death in the Kidney.

    PubMed

    Havasi, Andrea; Dong, Zheng

    2016-05-01

    Many common renal insults such as ischemia and toxic injury primarily target the tubular epithelial cells, especially the highly metabolically active proximal tubular segment. Tubular epithelial cells are particularly dependent on autophagy to maintain homeostasis and respond to stressors. The pattern of autophagy in the kidney has a unique spatial and chronologic signature. Recent evidence has shown that there is complex cross-talk between autophagy and various cell death pathways. This review specifically discusses the interplay between autophagy and cell death in the renal tubular epithelia. It is imperative to review this topic because recent discoveries have improved our mechanistic understanding of the autophagic process and have highlighted its broad clinical applications, making autophagy a major target for drug development. PMID:27339383

  15. Cannabinoid-associated cell death mechanisms in tumor models (review).

    PubMed

    Calvaruso, Giuseppe; Pellerito, Ornella; Notaro, Antonietta; Giuliano, Michela

    2012-08-01

    In recent years, cannabinoids (the active components of Cannabis sativa) and their derivatives have received considerable interest due to findings that they can affect the viability and invasiveness of a variety of different cancer cells. Moreover, in addition to their inhibitory effects on tumor growth and migration, angiogenesis and metastasis, the ability of these compounds to induce different pathways of cell death has been highlighted. Here, we review the most recent results generating interest in the field of death mechanisms induced by cannabinoids in cancer cells. In particular, we analyze the pathways triggered by cannabinoids to induce apoptosis or autophagy and investigate the interplay between the two processes. Overall, the results reported here suggest that the exploration of molecular mechanisms induced by cannabinoids in cancer cells can contribute to the development of safe and effective treatments in cancer therapy. PMID:22614735

  16. Docosahexaenoic acid prevents paraquat-induced reactive oxygen species production in dopaminergic neurons via enhancement of glutathione homeostasis

    SciTech Connect

    Lee, Hyoung Jun; Han, Jeongsu; Jang, Yunseon; Kim, Soo Jeong; Park, Ji Hoon; Seo, Kang Sik; Jeong, Soyeon; Shin, Soyeon; Lim, Kyu; Heo, Jun Young; Kweon, Gi Ryang

    2015-01-30

    Highlights: • DHA prevents PQ-induced dopaminergic neuronal loss via decreasing of excessive ROS. • DHA increases GR and GCLm derivate GSH pool by enhancement of Nrf2 expression. • Protective mechanism is removal of PQ-induced ROS via DHA-dependent GSH pool. • DHA may be a good preventive strategy for Parkinson’s disease (PD) therapy. - Abstract: Omega-3 polyunsaturated fatty acid levels are reduced in the substantia nigra area in Parkinson’s disease patients and animal models, implicating docosahexaenoic acid (DHA) as a potential treatment for preventing Parkinson’s disease and suggesting the need for investigations into how DHA might protect against neurotoxin-induced dopaminergic neuron loss. The herbicide paraquat (PQ) induces dopaminergic neuron loss through the excessive production of reactive oxygen species (ROS). We found that treatment of dopaminergic SN4741 cells with PQ reduced cell viability in a dose-dependent manner, but pretreatment with DHA ameliorated the toxic effect of PQ. To determine the toxic mechanism of PQ, we measured intracellular ROS content in different organelles with specific dyes. As expected, all types of ROS were increased by PQ treatment, but DHA pretreatment selectively decreased cytosolic hydrogen peroxide content. Furthermore, DHA treatment-induced increases in glutathione reductase and glutamate cysteine ligase modifier subunit (GCLm) mRNA expression were positively correlated with glutathione (GSH) content. Consistent with this increase in GCLm mRNA levels, Western blot analysis revealed that DHA pretreatment increased nuclear factor-erythroid 2 related factor 2 (Nrf2) protein levels. These findings indicate that DHA prevents PQ-induced neuronal cell loss by enhancing Nrf2-regulated GSH homeostasis.

  17. The DNA damage-induced cell death response: a roadmap to kill cancer cells.

    PubMed

    Matt, Sonja; Hofmann, Thomas G

    2016-08-01

    Upon massive DNA damage cells fail to undergo productive DNA repair and trigger the cell death response. Resistance to cell death is linked to cellular transformation and carcinogenesis as well as radio- and chemoresistance, making the underlying signaling pathways a promising target for therapeutic intervention. Diverse DNA damage-induced cell death pathways are operative in mammalian cells and finally culminate in the induction of programmed cell death via activation of apoptosis or necroptosis. These signaling routes affect nuclear, mitochondria- and plasma membrane-associated key molecules to activate the apoptotic or necroptotic response. In this review, we highlight the main signaling pathways, molecular players and mechanisms guiding the DNA damage-induced cell death response. PMID:26791483

  18. [Membrane permeability of brain cell processes after death].

    PubMed

    Agafonov, V A

    1975-07-01

    Experiments were conducted on rats. A study was made of persistence of semipermeability of the membranes of the cell processes of the brain (contraction) with the action of a hypertonic buffer at various periods after death. The membranes of the processes proved to retain the property of semi-permeability even 48 hours after death. Prefixation of the postmortem material in the glutaraldehyde did not influence the sensitivity of the membranes of the processes to the osmotic strength of the surrounding solution. PMID:1227661

  19. Rational Development of a Cytotoxic Peptide to Trigger Cell Death

    PubMed Central

    Boohaker, Rebecca J.; Zhang, Ge; Lee, Michael W.; Nemec, Kathleen N.; Santra, Santimukul; Perez, J. Manuel; Khaled, Annette R.

    2012-01-01

    Defects in the apoptotic machinery can contribute to tumor formation and resistance to treatment, creating a need to identify new agents that kill cancer cells by alternative mechanisms. To this end, we examined the cytotoxic properties of a novel peptide, CT20p, derived from the C-terminal, alpha-9 helix of Bax, an amphipathic domain with putative membrane binding properties. Like many anti-microbial peptides, CT20p contains clusters of hydrophobic and cationic residues that could enable the peptide to associate with lipid membranes. CT20p caused the release of calcein from mitochondrial-like lipid vesicles without disrupting vesicle integrity and, when expressed as a fusion protein in cells, localized to mitochondria. The amphipathic nature of CT20p allowed it to be encapsulated in polymeric nanoparticles (NPs) that have the capacity to harbor targeting molecules, dyes or drugs. The resulting CT20p-NPs proved an effective killer of colon and breast cancer cells in vitro and in vivo, using a murine breast cancer tumor model. By introducing CT20p to Bax deficient cells, we demonstrated that the peptide’s lethal activity was independent of endogenous Bax. CT20p also caused an increase in the mitochondrial membrane potential that was followed by plasma membrane rupture and cell death, without the characteristic membrane asymmetry associated with apoptosis. We determined that cell death triggered by the CT20p-NPs was minimally dependent on effector caspases and resistant Bcl-2 over-expression, suggesting that it was independent of the intrinsic apoptotic death pathway. Furthermore, use of CT20p with the apoptosis-inducing drug, cisplatin, resulted in additive toxicity. These results reveal the novel features of CT20p that allow nanoparticle-mediated delivery to tumors and the potential application in combination therapies to activate multiple death pathways in cancer cells. PMID:22591113

  20. Glycosphingolipids and cell death: one aim, many ways.

    PubMed

    Garcia-Ruiz, Carmen; Morales, Albert; Fernández-Checa, José C

    2015-05-01

    Glycosphingolipids (GSLs) are a family of bioactive lipids that in addition to their role in the regulation of structural properties of membrane bilayers have emerged as crucial players in many biological processes and signal transduction pathways. Rather than being uniformly distributed within membrane bilayers, GSLs are localized in selective domains called lipid rafts where many signaling platforms operate. One of the most important functions of GSLs, particularly ceramide, is their ability to regulate cell death pathways and hence cell fate. This complex role is accomplished by the ability of GSLs to act in distinct subcellular strategic centers, such as mitochondria, endoplasmic reticulum (ER) or lysosomes to mediate apoptosis, ER stress, autophagy, lysosomal membrane permeabilization and necroptosis. Hence better understanding the role of GSLs in cell death may be of relevance for a number of pathological processes and diseases, including neurodegeneration, metabolic liver diseases and cancer. PMID:25637183

  1. Focally regulated endothelial proliferation and cell death in human synovium.

    PubMed Central

    Walsh, D. A.; Wade, M.; Mapp, P. I.; Blake, D. R.

    1998-01-01

    Angiogenesis and vascular insufficiency each may support the chronic synovial inflammation of rheumatoid arthritis. We have shown by quantitative immunohistochemistry and terminal uridyl deoxynucleotide nick end labeling that endothelial proliferation and cell death indices were each increased in synovia from patients with rheumatoid arthritis compared with osteoarthritic and noninflamed controls, whereas endothelial fractional areas did not differ significantly among disease groups. Markers of proliferation were associated with foci immunoreactive for vascular endothelial growth factor and integrin alpha(v)beta3, whereas cell death was observed in foci in which immunoreactivities for these factors were weak or absent. No association was found with thrombospondin immunoreactivity. The balance between angiogenesis and vascular regression in rheumatoid synovitis may be determined by the focal expression of angiogenic and endothelial survival factors. Increased endothelial cell turnover may contribute to microvascular dysfunction and thereby facilitate persistent synovitis. Images Figure 1 Figure 3 Figure 4 PMID:9502411

  2. Glycosphingolipids and cell death: One aim, many ways

    PubMed Central

    Garcia-Ruiz, Carmen; Morales, Albert; Fernández-Checa, José C.

    2015-01-01

    Glycosphingolipids (GSLs) are a family of bioactive lipids that in addition to their role in the regulation of structural properties of membrane bilayers have emerged as crucial players in many biological processes and signal transduction pathways. Rather than being uniformly distributed within membrane bilayers, GSLs are localized in selective domains called lipid rafts where many signaling platforms operate. One of the most important functions of GSLs, particularly ceramide, is their ability to regulate cell death pathways and hence cell fate. This complex role is accomplished by the ability of GSLs to act in distinct subcellular strategic centers, such as mitochondria, endoplasmic reticulum (ER) or lysosomes to mediate apoptosis, ER stress, autophagy, lysosomal membrane permeabilization and necroptosis. Hence better understanding the role of GSLs in cell death may be of relevance for a number of pathological processes and diseases, including neurodegeneration, metabolic liver diseases and cancer. PMID:25637183

  3. Lead-induced cell death in testes of young rats.

    PubMed

    Adhikari, N; Sinha, N; Narayan, R; Saxena, D K

    2001-01-01

    Lead is a well-documented testicular toxicant. The present work was planned to study the occurrence of germ cell death after lead administration. Young growing rats were treated with 5, 10 and 20 mg kg(-1) body weight of lead for 2 weeks. Cell death was assessed by employing in situ TUNEL staining, DNA electrophoresis and morphological examination of the tubules. The results showed that Pb induced significant numbers of germ cells to undergo apoptosis in the seminiferous tubules of rats treated with 20 mg kg(-1) body weight. However, DNA fragmentation was not detected at any of the doses. The level of lead accumulation in the testis increased in a dose-dependent manner. PMID:11481659

  4. Leaf Age-Dependent Photoprotective and Antioxidative Response Mechanisms to Paraquat-Induced Oxidative Stress in Arabidopsis thaliana.

    PubMed

    Moustaka, Julietta; Tanou, Georgia; Adamakis, Ioannis-Dimosthenis; Eleftheriou, Eleftherios P; Moustakas, Michael

    2015-01-01

    Exposure of Arabidopsis thaliana young and mature leaves to the herbicide paraquat (Pq) resulted in a localized increase of hydrogen peroxide (H2O2) in the leaf veins and the neighboring mesophyll cells, but this increase was not similar in the two leaf types. Increased H2O2 production was concomitant with closed reaction centers (qP). Thirty min after Pq exposure despite the induction of the photoprotective mechanism of non-photochemical quenching (NPQ) in mature leaves, H2O2 production was lower in young leaves mainly due to the higher increase activity of ascorbate peroxidase (APX). Later, 60 min after Pq exposure, the total antioxidant capacity of young leaves was not sufficient to scavenge the excess reactive oxygen species (ROS) that were formed, and thus, a higher H2O2 accumulation in young leaves occurred. The energy allocation of absorbed light in photosystem II (PSII) suggests the existence of a differential photoprotective regulatory mechanism in the two leaf types to the time-course Pq exposure accompanied by differential antioxidant protection mechanisms. It is concluded that tolerance to Pq-induced oxidative stress is related to the redox state of quinone A (QA). PMID:26096005

  5. Leaf Age-Dependent Photoprotective and Antioxidative Response Mechanisms to Paraquat-Induced Oxidative Stress in Arabidopsis thaliana

    PubMed Central

    Moustaka, Julietta; Tanou, Georgia; Adamakis, Ioannis-Dimosthenis; Eleftheriou, Eleftherios P.; Moustakas, Michael

    2015-01-01

    Exposure of Arabidopsis thaliana young and mature leaves to the herbicide paraquat (Pq) resulted in a localized increase of hydrogen peroxide (H2O2) in the leaf veins and the neighboring mesophyll cells, but this increase was not similar in the two leaf types. Increased H2O2 production was concomitant with closed reaction centers (qP). Thirty min after Pq exposure despite the induction of the photoprotective mechanism of non-photochemical quenching (NPQ) in mature leaves, H2O2 production was lower in young leaves mainly due to the higher increase activity of ascorbate peroxidase (APX). Later, 60 min after Pq exposure, the total antioxidant capacity of young leaves was not sufficient to scavenge the excess reactive oxygen species (ROS) that were formed, and thus, a higher H2O2 accumulation in young leaves occurred. The energy allocation of absorbed light in photosystem II (PSII) suggests the existence of a differential photoprotective regulatory mechanism in the two leaf types to the time-course Pq exposure accompanied by differential antioxidant protection mechanisms. It is concluded that tolerance to Pq-induced oxidative stress is related to the redox state of quinone A (QA). PMID:26096005

  6. Blockade of maitotoxin-induced oncotic cell death reveals zeiosis

    PubMed Central

    Estacion, Mark; Schilling, William P

    2002-01-01

    Background Maitotoxin (MTX) initiates cell death by sequentially activating 1) Ca2+ influx via non-selective cation channels, 2) uptake of vital dyes via formation of large pores, and 3) release of lactate dehydrogenase, an indication of cell lysis. MTX also causes formation of membrane blebs, which dramatically dilate during the cytolysis phase. To determine the role of phospholipase C (PLC) in the cell death cascade, U73122, a specific inhibitor of PLC, and U73343, an inactive analog, were examined on MTX-induced responses in bovine aortic endothelial cells. Results Addition of either U73122 or U73343, prior to MTX, produced a concentration-dependent inhibition of the cell death cascade (IC50 ≈ 1.9 and 0.66 μM, respectively) suggesting that the effect of these agents was independent of PLC. Addition of U73343 shortly after MTX, prevented or attenuated the effects of the toxin, but addition at later times had little or no effect. Time-lapse videomicroscopy showed that U73343 dramatically altered the blebbing profile of MTX-treated cells. Specifically, U73343 blocked bleb dilation and converted the initial blebbing event into "zeiosis", a type of membrane blebbing commonly associated with apoptosis. Cells challenged with MTX and rescued by subsequent addition of U73343, showed enhanced caspase-3 activity 48 hr after the initial insult, consistent with activation of the apoptotic program. Conclusions Within minutes of MTX addition, endothelial cells die by oncosis. Rescue by addition of U73343 shortly after MTX showed that a small percentage of cells are destined to die by oncosis, but that a larger percentage survive; cells that survive the initial insult exhibit zeiosis and may ultimately die by apoptotic mechanisms. PMID:11825342

  7. Molecular and Translational Classifications of DAMPs in Immunogenic Cell Death

    PubMed Central

    Garg, Abhishek D.; Galluzzi, Lorenzo; Apetoh, Lionel; Baert, Thais; Birge, Raymond B.; Bravo-San Pedro, José Manuel; Breckpot, Karine; Brough, David; Chaurio, Ricardo; Cirone, Mara; Coosemans, An; Coulie, Pierre G.; De Ruysscher, Dirk; Dini, Luciana; de Witte, Peter; Dudek-Peric, Aleksandra M.; Faggioni, Alberto; Fucikova, Jitka; Gaipl, Udo S.; Golab, Jakub; Gougeon, Marie-Lise; Hamblin, Michael R.; Hemminki, Akseli; Herrmann, Martin; Hodge, James W.; Kepp, Oliver; Kroemer, Guido; Krysko, Dmitri V.; Land, Walter G.; Madeo, Frank; Manfredi, Angelo A.; Mattarollo, Stephen R.; Maueroder, Christian; Merendino, Nicolò; Multhoff, Gabriele; Pabst, Thomas; Ricci, Jean-Ehrland; Riganti, Chiara; Romano, Erminia; Rufo, Nicole; Smyth, Mark J.; Sonnemann, Jürgen; Spisek, Radek; Stagg, John; Vacchelli, Erika; Vandenabeele, Peter; Vandenberk, Lien; Van den Eynde, Benoit J.; Van Gool, Stefaan; Velotti, Francesca; Zitvogel, Laurence; Agostinis, Patrizia

    2015-01-01

    The immunogenicity of malignant cells has recently been acknowledged as a critical determinant of efficacy in cancer therapy. Thus, besides developing direct immunostimulatory regimens, including dendritic cell-based vaccines, checkpoint-blocking therapies, and adoptive T-cell transfer, researchers have started to focus on the overall immunobiology of neoplastic cells. It is now clear that cancer cells can succumb to some anticancer therapies by undergoing a peculiar form of cell death that is characterized by an increased immunogenic potential, owing to the emission of the so-called “damage-associated molecular patterns” (DAMPs). The emission of DAMPs and other immunostimulatory factors by cells succumbing to immunogenic cell death (ICD) favors the establishment of a productive interface with the immune system. This results in the elicitation of tumor-targeting immune responses associated with the elimination of residual, treatment-resistant cancer cells, as well as with the establishment of immunological memory. Although ICD has been characterized with increased precision since its discovery, several questions remain to be addressed. Here, we summarize and tabulate the main molecular, immunological, preclinical, and clinical aspects of ICD, in an attempt to capture the essence of this phenomenon, and identify future challenges for this rapidly expanding field of investigation. PMID:26635802

  8. Methylglyoxal induces mitochondrial dysfunction and cell death in liver.

    PubMed

    Seo, Kyuhwa; Ki, Sung Hwan; Shin, Sang Mi

    2014-09-01

    Degradation of glucose is aberrantly increased in hyperglycemia, which causes various harmful effects on the liver. Methylglyoxal is produced during glucose degradation and the levels of methylglyoxal are increased in diabetes patients. In this study we investigated whether methylglyoxal induces mitochondrial impairment and apoptosis in HepG2 cells and induces liver toxicity in vivo. Methylglyoxal caused apoptotic cell death in HepG2 cells. Moreover, methylglyoxal significantly promoted the production of reactive oxygen species (ROS) and depleted glutathione (GSH) content. Pretreatment with antioxidants caused a marked decrease in methylglyoxal-induced apoptosis, indicating that oxidant species are involved in the apoptotic process. Methylglyoxal treatment induced mitochondrial permeability transition, which represents mitochondrial impairment. However, pretreatment with cyclosporin A, an inhibitor of the formation of the permeability transition pore, partially inhibited methylglyoxal-induced cell death. Furthermore, acute treatment of mice with methylglyoxal increased the plasma levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST), indicating liver toxicity. Collectively, our results showed that methylglyoxal increases cell death and induces liver toxicity, which results from ROS-mediated mitochondrial dysfunction and oxidative stress. PMID:25343013

  9. Cell death is involved in sexual dimorphism during preimplantation development.

    PubMed

    Oliveira, C S; Saraiva, N Z; de Lima, M R; Oliveira, L Z; Serapião, R V; Garcia, J M; Borges, C A V; Camargo, L S A

    2016-02-01

    In bovine preimplantation development, female embryos progress at lower rates and originate smaller blastocysts than male counterparts. Although sex-specific gene expression patterns are reported, when and how sex dimorphism is established is not clear. Differences among female and male early development can be useful for human assisted reproductive medicine, when X-linked disorders risk is detected, and for genetic breeding programs, especially in dairy cattle, which requires female animals for milk production. The aim of this study was to characterize the development of female and male embryos, attempting to identify sex effects during preimplantation development and the role of cell death in this process. Using sex-sorted semen from three different bulls for fertilization, we compared kinetics of bovine sex-specific embryos in six time points, and cell death was assessed in viable embryos. For kinetics analysis, we detected an increased population of female embryos arrested at 48 and 120h.p.i., suggesting this time points as delicate stages of development for female embryos that should be considered for testing improvement strategies for assisted reproductive technologies. Assessing viable embryos quality, we found 144h.p.i. is the first time point when viable embryos are phenotypically distinct: cell number is decreased, and apoptosis and cell fragmentation are increased in female embryos at this stage. These new results lead us to propose that sex dimorphism in viable embryos is established during morula-blastocyst transition, and cell death is involved in this process. PMID:26752320

  10. Unraveling the mechanism of cell death induced by chemical fibrils

    PubMed Central

    Julien, Olivier; Kampmann, Martin; Bassik, Michael C.; Zorn, Julie A.; Venditto, Vincent J.; Shimbo, Kazutaka; Agard, Nicholas J.; Shimada, Kenichi; Rheingold, Arnold L.; Stockwell, Brent R.; Weissman, Jonathan S.

    2014-01-01

    We previously discovered a small-molecule inducer of cell death, named 1541, that non-covalently self-assembles into chemical fibrils (“chemi-fibrils”) and activates procaspase-3 in vitro. We report here that 1541-induced cell death is caused by the fibrillar, rather than the soluble form of the drug. An shRNA screen reveals that knockdown of genes involved in endocytosis, vesicle trafficking, and lysosomal acidification causes partial 1541 resistance. We confirm the role of these pathways using pharmacological inhibitors. Microscopy shows that the fluorescent chemi-fibrils accumulate in punctae inside cells that partially co-localize with lysosomes. Notably, the chemi-fibrils bind and induce liposome leakage in vitro, suggesting they may do the same in cells. The chemi-fibrils induce extensive proteolysis including caspase substrates, yet modulatory profiling reveals that chemi-fibrils form a distinct class from existing inducers of cell death. The chemi-fibrils share similarities to proteinaceous fibrils and may provide insight into their mechanism of cellular toxicity. PMID:25262416

  11. Multifactorial theory applied to the neurotoxicity of paraquat and paraquat-induced mechanisms of developing Parkinson's disease.

    PubMed

    Zhang, Xiao-Feng; Thompson, Mark; Xu, Yi-Hua

    2016-05-01

    Laboratory studies involving repeated exposure to paraquat (PQ) in different animal models can induce many of the pathological features of Parkinson's disease (PD), such as the loss of dopaminergic neurons in the nigrostriatal dopamine system. Epidemiological studies identify an increased risk of developing PD in human populations living in areas where PQ exposure is likely to occur and among workers lacking appropriate protective equipment. The mechanisms involved in developing PD may not be due to any single cause, but rather a multifactorial situation may exist where PQ exposure may cause PD in some circumstances. Multifactorial theory is adopted into this review that includes a number of sub-cellular mechanisms to explain the pathogenesis of PD. The theory is placed into an environmental context of chronic low-dose exposure to PQ that consequently acts as an oxidative stress inducer. Oxidative stress and the metabolic processes of PQ-inducing excitotoxicity, α-synuclein aggregate formation, autophagy, alteration of dopamine catabolism, and inactivation of tyrosine hydroxylase are positioned as causes for the loss of dopaminergic cells. The environmental context and biochemistry of PQ in soils, water, and organisms is also reviewed to identify potential routes that can lead to chronic rates of low-dose exposure that would replicate the type of response that is observed in animal models, epidemiological studies, and other types of laboratory investigations involving PQ exposure. The purpose of this review is to synthesize key relations and summarize hypotheses linking PD to PQ exposure by using the multifactorial approach. Recommendations are given to integrate laboratory methods to the environmental context as a means to improve on experimental design. The multifactorial approach is necessary for conducting valid tests of causal relations, for understanding of potential relations between PD and PQ exposure, and may prevent further delay in solving what has

  12. DNA methylation and differential gene regulation in photoreceptor cell death

    PubMed Central

    Farinelli, P; Perera, A; Arango-Gonzalez, B; Trifunovic, D; Wagner, M; Carell, T; Biel, M; Zrenner, E; Michalakis, S; Paquet-Durand, F; Ekström, P A R

    2014-01-01

    Retinitis pigmentosa (RP) defines a group of inherited degenerative retinal diseases causing progressive loss of photoreceptors. To this day, RP is still untreatable and rational treatment development will require a thorough understanding of the underlying cell death mechanisms. Methylation of the DNA base cytosine by DNA methyltransferases (DNMTs) is an important epigenetic factor regulating gene expression, cell differentiation, cell death, and survival. Previous studies suggested an involvement of epigenetic mechanisms in RP, and in this study, increased cytosine methylation was detected in dying photoreceptors in the rd1, rd2, P23H, and S334ter rodent models for RP. Ultrastructural analysis of photoreceptor nuclear morphology in the rd1 mouse model for RP revealed a severely altered chromatin structure during retinal degeneration that coincided with an increased expression of the DNMT isozyme DNMT3a. To identify disease-specific differentially methylated DNA regions (DMRs) on a genomic level, we immunoprecipitated methylated DNA fragments and subsequently analyzed them with a targeted microarray. Genome-wide comparison of DMRs between rd1 and wild-type retina revealed hypermethylation of genes involved in cell death and survival as well as cell morphology and nervous system development. When correlating DMRs with gene expression data, we found that hypermethylation occurred alongside transcriptional repression. Consistently, motif analysis showed that binding sites of several important transcription factors for retinal physiology were hypermethylated in the mutant model, which also correlated with transcriptional silencing of their respective target genes. Finally, inhibition of DNMTs in rd1 organotypic retinal explants using decitabine resulted in a substantial reduction of photoreceptor cell death, suggesting inhibition of DNA methylation as a potential novel treatment in RP. PMID:25476906

  13. DNA methylation and differential gene regulation in photoreceptor cell death.

    PubMed

    Farinelli, P; Perera, A; Arango-Gonzalez, B; Trifunovic, D; Wagner, M; Carell, T; Biel, M; Zrenner, E; Michalakis, S; Paquet-Durand, F; Ekström, P A R

    2014-01-01

    Retinitis pigmentosa (RP) defines a group of inherited degenerative retinal diseases causing progressive loss of photoreceptors. To this day, RP is still untreatable and rational treatment development will require a thorough understanding of the underlying cell death mechanisms. Methylation of the DNA base cytosine by DNA methyltransferases (DNMTs) is an important epigenetic factor regulating gene expression, cell differentiation, cell death, and survival. Previous studies suggested an involvement of epigenetic mechanisms in RP, and in this study, increased cytosine methylation was detected in dying photoreceptors in the rd1, rd2, P23H, and S334ter rodent models for RP. Ultrastructural analysis of photoreceptor nuclear morphology in the rd1 mouse model for RP revealed a severely altered chromatin structure during retinal degeneration that coincided with an increased expression of the DNMT isozyme DNMT3a. To identify disease-specific differentially methylated DNA regions (DMRs) on a genomic level, we immunoprecipitated methylated DNA fragments and subsequently analyzed them with a targeted microarray. Genome-wide comparison of DMRs between rd1 and wild-type retina revealed hypermethylation of genes involved in cell death and survival as well as cell morphology and nervous system development. When correlating DMRs with gene expression data, we found that hypermethylation occurred alongside transcriptional repression. Consistently, motif analysis showed that binding sites of several important transcription factors for retinal physiology were hypermethylated in the mutant model, which also correlated with transcriptional silencing of their respective target genes. Finally, inhibition of DNMTs in rd1 organotypic retinal explants using decitabine resulted in a substantial reduction of photoreceptor cell death, suggesting inhibition of DNA methylation as a potential novel treatment in RP. PMID:25476906

  14. Sensitization of acute lymphoblastic leukemia cells for LCL161-induced cell death by targeting redox homeostasis.

    PubMed

    Haß, Christina; Belz, Katharina; Schoeneberger, Hannah; Fulda, Simone

    2016-04-01

    Disturbed redox homeostasis with both elevated reactive oxygen species (ROS) levels and antioxidant defense mechanisms has been reported in acute lymphoblastic leukemia (ALL). We therefore hypothesized that inhibition of pathways responsible for ROS detoxification renders ALL cells more susceptible for cell death. Here, we report that pharmacological inhibitors of key pathways for the elimination of ROS, i.e. Erastin, buthionine sulfoximine (BSO) and Auranofin, sensitize ALL cells for cell death upon treatment with the Smac mimetic LCL161 that antagonizes Inhibitor of Apoptosis (IAP) proteins. Erastin, BSO or Auranofin significantly increase LCL161-induced cell death and also act in concert with LCL161 to profoundly suppress long-term clonogenic survival in several ALL cell lines. Erastin or BSO cooperates with LCL161 to stimulate ROS production and lipid peroxidation prior to cell death. ROS production and lipid peroxidation are required for this cotreatment-induced cell death, since ROS scavengers or pharmacological inhibition of lipid peroxidation provides significant protection against cell death. These results emphasize that inhibition of antioxidant defense mechanisms can serve as a potent approach to prime ALL cells for LCL161-induced cell death. PMID:26774450

  15. Programmed cell death and clearance of cell corpses in Caenorhabditis elegans.

    PubMed

    Wang, Xiaochen; Yang, Chonglin

    2016-06-01

    Programmed cell death is critical to the development of diverse animal species from C. elegans to humans. In C. elegans, the cell death program has three genetically distinguishable phases. During the cell suicide phase, the core cell death machinery is activated through a protein interaction cascade. This activates the caspase CED-3, which promotes numerous pro-apoptotic activities including DNA degradation and exposure of the phosphatidylserine "eat me" signal on the cell corpse surface. Specification of the cell death fate involves transcriptional activation of the cell death initiator EGL-1 or the caspase CED-3 by coordinated actions of specific transcription factors in distinct cell types. In the cell corpse clearance stage, recognition of cell corpses by phagocytes triggers several signaling pathways to induce phagocytosis of apoptotic cell corpses. Cell corpse-enclosing phagosomes ultimately fuse with lysosomes for digestion of phagosomal contents. This article summarizes our current knowledge about programmed cell death and clearance of cell corpses in C. elegans. PMID:27048817

  16. Ubiquitin at the crossroad of cell death and survival

    PubMed Central

    Chen, Yu-Shan; Qiu, Xiao-Bo

    2013-01-01

    Ubiquitination is crucial for cellular processes, such as protein degradation, apoptosis, autophagy, and cell cycle progression. Dysregulation of the ubiquitination network accounts for the development of numerous diseases, including cancer. Thus, targeting ubiquitination is a promising strategy in cancer therapy. Both apoptosis and autophagy are involved in tumorigenesis and response to cancer therapy. Although both are categorized as types of cell death, autophagy is generally considered to have protective functions, including protecting cells from apoptosis under certain cellular stress conditions. This review highlights recent advances in understanding the regulation of apoptosis and autophagy by ubiquitination. PMID:23816559

  17. Glucose Levels in Culture Medium Determine Cell Death Mode in MPP+-treated Dopaminergic Neuronal Cells

    PubMed Central

    Yoon, So-Young

    2015-01-01

    We previously demonstrated that 1-methyl-4-phenylpyridinium (MPP+) causes caspase-independent, non-apoptotic death of dopaminergic (DA) neuronal cells. Here, we specifically examined whether change of glucose concentration in culture medium may play a role for determining cell death modes of DA neurons following MPP+ treatment. By incubating MN9D cells in medium containing varying concentrations of glucose (5~35 mM), we found that cells underwent a distinct cell death as determined by morphological and biochemical criteria. At 5~10 mM glucose concentration (low glucose levels), MPP+ induced typical of the apoptotic dell death accompanied with caspase activation and DNA fragmentation as well as cell shrinkage. In contrast, MN9D cells cultivated in medium containing more than 17.5 mM (high glucose levels) did not demonstrate any of these changes. Subsequently, we observed that MPP+ at low glucose levels but not high glucose levels led to ROS generation and subsequent JNK activation. Therefore, MPP+-induced cell death only at low glucose levels was significantly ameliorated following co-treatment with ROS scavenger, caspase inhibitor or JNK inhibitor. We basically confirmed the quite similar pattern of cell death in primary cultures of DA neurons. Taken together, our results suggest that a biochemically distinct cell death mode is recruited by MPP+ depending on extracellular glucose levels. PMID:26412968

  18. In vitro apoptotic cell death during erythroid differentiation.

    PubMed

    Zamai, L; Burattini, S; Luchetti, F; Canonico, B; Ferri, P; Melloni, E; Gonelli, A; Guidotti, L; Papa, S; Falcieri, E

    2004-03-01

    Erythropoiesis occurs in bone marrow and it has been shown that during in vivo erythroid differentiation some immature erythroblasts undergo apoptosis. In this regard, it is known that immature erythroblasts are FasL- and TRAIL-sensitive and can be killed by cells expressing these ligand molecules. In the present study, we have investigated the cell death phenomenon that occurs during a common unilineage model of erythroid development. Purified CD34+ human haemopoietic progenitors were cultured in vitro in the presence of SCF, IL-3 and erythropoietin. Their differentiation stages and apoptosis were followed by multiple technical approaches. Flow cytometric evaluation of surface and intracellular molecules revealed that glycophorin A appeared at day 3-4 of incubation and about 75% of viable cells co-expressed high density glycophorin A (Gly(bright)) and adult haemoglobin at day 14 of culture, indicating that this system reasonably recapitulates in vivo normal erythropoiesis. Interestingly, when mature (Gly(bright)) erythroid cells reached their higher percentages (day 14) almost half of cultured cells were apoptotic. Morphological studies indicated that the majority of dead cells contained cytoplasmic granular material typical of basophilic stage, and DNA analysis by flow cytometry and TUNEL reaction revealed nuclear fragmentation. These observations indicate that in vitro unilineage erythroid differentiation, as in vivo, is associated with apoptotic cell death of cells with characteristics of basophilic erythroblasts. We suggest that the interactions between different death receptors on immature basophilic erythroblasts with their ligands on more mature erythroblasts may contribute to induce apoptosis in vitro. PMID:15004520

  19. Bee Venom Protects against Rotenone-Induced Cell Death in NSC34 Motor Neuron Cells.

    PubMed

    Jung, So Young; Lee, Kang-Woo; Choi, Sun-Mi; Yang, Eun Jin

    2015-09-01

    Rotenone, an inhibitor of mitochondrial complex I of the mitochondrial respiratory chain, is known to elevate mitochondrial reactive oxygen species and induce apoptosis via activation of the caspase-3 pathway. Bee venom (BV) extracted from honey bees has been widely used in oriental medicine and contains melittin, apamin, adolapin, mast cell-degranulating peptide, and phospholipase A₂. In this study, we tested the effects of BV on neuronal cell death by examining rotenone-induced mitochondrial dysfunction. NSC34 motor neuron cells were pretreated with 2.5 μg/mL BV and stimulated with 10 μM rotenone to induce cell toxicity. We assessed cell death by Western blotting using specific antibodies, such as phospho-ERK1/2, phospho-JNK, and cleaved capase-3 and performed an MTT assay for evaluation of cell death and mitochondria staining. Pretreatment with 2.5 μg/mL BV had a neuroprotective effect against 10 μM rotenone-induced cell death in NSC34 motor neuron cells. Pre-treatment with BV significantly enhanced cell viability and ameliorated mitochondrial impairment in rotenone-treated cellular model. Moreover, BV treatment inhibited the activation of JNK signaling and cleaved caspase-3 related to cell death and increased ERK phosphorylation involved in cell survival in rotenone-treated NSC34 motor neuron cells. Taken together, we suggest that BV treatment can be useful for protection of neurons against oxidative stress or neurotoxin-induced cell death. PMID:26402700

  20. Bee Venom Protects against Rotenone-Induced Cell Death in NSC34 Motor Neuron Cells

    PubMed Central

    Jung, So Young; Lee, Kang-Woo; Choi, Sun-Mi; Yang, Eun Jin

    2015-01-01

    Rotenone, an inhibitor of mitochondrial complex I of the mitochondrial respiratory chain, is known to elevate mitochondrial reactive oxygen species and induce apoptosis via activation of the caspase-3 pathway. Bee venom (BV) extracted from honey bees has been widely used in oriental medicine and contains melittin, apamin, adolapin, mast cell-degranulating peptide, and phospholipase A2. In this study, we tested the effects of BV on neuronal cell death by examining rotenone-induced mitochondrial dysfunction. NSC34 motor neuron cells were pretreated with 2.5 μg/mL BV and stimulated with 10 μM rotenone to induce cell toxicity. We assessed cell death by Western blotting using specific antibodies, such as phospho-ERK1/2, phospho-JNK, and cleaved capase-3 and performed an MTT assay for evaluation of cell death and mitochondria staining. Pretreatment with 2.5 μg/mL BV had a neuroprotective effect against 10 μM rotenone-induced cell death in NSC34 motor neuron cells. Pre-treatment with BV significantly enhanced cell viability and ameliorated mitochondrial impairment in rotenone-treated cellular model. Moreover, BV treatment inhibited the activation of JNK signaling and cleaved caspase-3 related to cell death and increased ERK phosphorylation involved in cell survival in rotenone-treated NSC34 motor neuron cells. Taken together, we suggest that BV treatment can be useful for protection of neurons against oxidative stress or neurotoxin-induced cell death. PMID:26402700

  1. Physical modalities inducing immunogenic tumor cell death for cancer immunotherapy

    PubMed Central

    Adkins, Irena; Fucikova, Jitka; Garg, Abhishek D; Agostinis, Patrizia; Špíšek, Radek

    2015-01-01

    The concept of immunogenic cancer cell death (ICD), as originally observed during the treatment with several chemotherapeutics or ionizing irradiation, has revolutionized the view on the development of new anticancer therapies. ICD is defined by endoplasmic reticulum (ER) stress response, reactive oxygen species (ROS) generation, emission of danger-associated molecular patterns and induction of antitumor immunity. Here we describe known and emerging cancer cell death-inducing physical modalities, such as ionizing irradiation, ultraviolet C light, Photodynamic Therapy (PDT) with Hypericin, high hydrostatic pressure (HHP) and hyperthermia (HT), which have been shown to elicit effective antitumor immunity. We discuss the evidence of ICD induced by these modalities in cancer patients together with their applicability in immunotherapeutic protocols and anticancer vaccine development. PMID:25964865

  2. Understanding Dopaminergic Cell Death Pathways in Parkinson Disease.

    PubMed

    Michel, Patrick P; Hirsch, Etienne C; Hunot, Stéphane

    2016-05-18

    Parkinson disease (PD) is a multifactorial neurodegenerative disorder, the etiology of which remains largely unknown. Progressive impairment of voluntary motor control, which represents the primary clinical feature of the disease, is caused by a loss of midbrain substantia nigra dopamine (DA) neurons. We present here a synthetic overview of cell-autonomous mechanisms that are likely to participate in DA cell death in both sporadic and inherited forms of the disease. In particular, we describe how damage to vulnerable DA neurons may arise from cellular disturbances produced by protein misfolding and aggregation, disruption of autophagic catabolism, endoplasmic reticulum (ER) stress, mitochondrial dysfunction, or loss of calcium homeostasis. Where pertinent, we show how these mechanisms may mutually cooperate to promote neuronal death. PMID:27196972

  3. Identification of a mitotic death signature in cancer cell lines.

    PubMed

    Sakurikar, Nandini; Eichhorn, Joshua M; Alford, Sarah E; Chambers, Timothy C

    2014-02-28

    This study examined the molecular mechanism of action of anti-mitotic drugs. The hypothesis was tested that death in mitosis occurs through sustained mitotic arrest with robust Cdk1 signaling causing complete phosphorylation of Mcl-1 and Bcl-xL, and conversely, that mitotic slippage is associated with incomplete phosphorylation of Mcl-1/Bcl-xL. The results, obtained from studying six different cancer cell lines, strongly support the hypothesis and identify for the first time a unique molecular signature for mitotic death. The findings represent an important advance in understanding anti-mitotic drug action and provide insight into cancer cell susceptibility to such drugs which has important clinical implications. PMID:24099917

  4. Molecular mechanisms of cell death in intervertebral disc degeneration (Review).

    PubMed

    Zhang, Fan; Zhao, Xueling; Shen, Hongxing; Zhang, Caiguo

    2016-06-01

    Intervertebral discs (IVDs) are complex structures that consist of three parts, namely, nucleus pulposus, annulus fibrosus and cartilage endplates. With aging, IVDs gradually degenerate as a consequence of many factors, such as microenvironment changes and cell death. Human clinical trial and animal model studies have documented that cell death, particularly apoptosis and autophagy, significantly contribute to IVD degeneration. The mechanisms underlying this phenomenon include the activation of apoptotic pathways and the regulation of autophagy in response to nutrient deprivation and multiple stresses. In this review, we briefly summarize recent progress in understanding the function and regulation of apoptosis and autophagy signaling pathways. In particular, we focus on studies that reveal the functional mechanisms of these pathways in IVD degeneration. PMID:27121482

  5. Molecular mechanisms of cell death in intervertebral disc degeneration (Review)

    PubMed Central

    ZHANG, FAN; ZHAO, XUELING; SHEN, HONGXING; ZHANG, CAIGUO

    2016-01-01

    Intervertebral discs (IVDs) are complex structures that consist of three parts, namely, nucleus pulposus, annulus fibrosus and cartilage endplates. With aging, IVDs gradually degenerate as a consequence of many factors, such as microenvironment changes and cell death. Human clinical trial and animal model studies have documented that cell death, particularly apoptosis and autophagy, significantly contribute to IVD degeneration. The mechanisms underlying this phenomenon include the activation of apoptotic pathways and the regulation of autophagy in response to nutrient deprivation and multiple stresses. In this review, we briefly summarize recent progress in understanding the function and regulation of apoptosis and autophagy signaling pathways. In particular, we focus on studies that reveal the functional mechanisms of these pathways in IVD degeneration. PMID:27121482

  6. Ayanin diacetate-induced cell death is amplified by TRAIL in human leukemia cells

    SciTech Connect

    Marrero, Maria Teresa; Estevez, Sara; Negrin, Gledy; Quintana, Jose; Leon, Francisco; Estevez, Francisco

    2012-11-09

    Highlights: Black-Right-Pointing-Pointer Ayanin diacetate as apoptotic inducer in leukemia cells. Black-Right-Pointing-Pointer Cell death was prevented by caspase inhibitors and by the overexpression of Bcl-x{sub L}. Black-Right-Pointing-Pointer The intrinsic and the extrinsic pathways are involved in the mechanism of action. Black-Right-Pointing-Pointer Death receptors are up-regulated and TRAIL enhances apoptotic cell death. -- Abstract: Here we demonstrate that the semi-synthetic flavonoid ayanin diacetate induces cell death selectively in leukemia cells without affecting the proliferation of normal lymphocytes. Incubation of human leukemia cells with ayanin diacetate induced G{sub 2}-M phase cell cycle arrest and apoptosis which was prevented by the non-specific caspase inhibitor z-VAD-fmk and reduced by the overexpression of Bcl-x{sub L}. Ayanin diacetate-induced cell death was found to be associated with: (i) loss of inner mitochondrial membrane potential, (ii) the release of cytochrome c, (iii) the activation of multiple caspases, (iv) cleavage of poly(ADP-ribose) polymerase and (v) the up-regulation of death receptors for TRAIL, DR4 and DR5. Moreover, the combined treatment with ayanin diacetate and TRAIL amplified cell death, compared to single treatments. These results provide a basis for further exploring the potential applications of this combination for the treatment of cancer.

  7. Orexin A attenuates palmitic acid-induced hypothalamic cell death.

    PubMed

    Duffy, Cayla M; Nixon, Joshua P; Butterick, Tammy A

    2016-09-01

    Palmitic acid (PA), an abundant dietary saturated fatty acid, contributes to obesity and hypothalamic dysregulation in part through increase in oxidative stress, insulin resistance, and neuroinflammation. Increased production of reactive oxygen species (ROS) as a result of PA exposure contributes to the onset of neuronal apoptosis. Additionally, high fat diets lead to changes in hypothalamic gene expression profiles including suppression of the anti-apoptotic protein B cell lymphoma 2 (Bcl-2) and upregulation of the pro-apoptotic protein B cell lymphoma 2 associated X protein (Bax). Orexin A (OXA), a hypothalamic peptide important in obesity resistance, also contributes to neuroprotection. Prior studies have demonstrated that OXA attenuates oxidative stress induced cell death. We hypothesized that OXA would be neuroprotective against PA induced cell death. To test this, we treated an immortalized hypothalamic cell line (designated mHypoA-1/2) with OXA and PA. We demonstrate that OXA attenuates PA-induced hypothalamic cell death via reduced caspase-3/7 apoptosis, stabilization of Bcl-2 gene expression, and reduced Bax/Bcl-2 gene expression ratio. We also found that OXA inhibits ROS production after PA exposure. Finally, we show that PA exposure in mHypoA-1/2 cells significantly reduces basal respiration, maximum respiration, ATP production, and reserve capacity. However, OXA treatment reverses PA-induced changes in intracellular metabolism, increasing basal respiration, maximum respiration, ATP production, and reserve capacity. Collectively, these results support that OXA protects against PA-induced hypothalamic dysregulation, and may represent one mechanism through which OXA can ameliorate effects of obesogenic diet on brain health. PMID:27449757

  8. Calcium oxalate toxicity in renal epithelial cells: the mediation of crystal size on cell death mode

    PubMed Central

    Sun, X-Y; Gan, Q-Z; Ouyang, J-M

    2015-01-01

    The cytotoxicity of calcium oxalate (CaOx) in renal epithelial cells has been studied extensively, but the cell death mode induced by CaOx with different physical properties, such as crystal size and crystal phase, has not been studied in detail. In this study, we comparatively investigated the differences of cell death mode induced by nano-sized (50 nm) and micron-sized (10 μm) calcium oxalate monohydrate (COM) and calcium oxalate dihydrate (COD) to explore the cell death mechanism. The effect of the exposure of nano-/micron-sized COM and COD crystals toward the African green monkey renal epithelial (Vero) cells were investigated by detecting cell cytoskeleton changes, lysosomal integrity, mitochondrial membrane potential (Δψm), apoptosis and/or necrosis, osteopontin (OPN) expression, and malondialdehyde (MDA) release. Nano-/micron-sized COM and COD crystals could cause apoptosis and necrosis simultaneously. Nano-sized crystals primarily caused apoptotic cell death, leading to cell shrinkage, phosphatidylserine ectropion, and nuclear shrinkage, whereas micron-sized crystals primarily caused necrotic cell death, leading to cell swelling and cell membrane and lysosome rupture. Nano-sized COM and COD crystals induced much greater cell death (sum of apoptosis and necrosis) than micron-sized crystals, and COM crystals showed higher cytotoxicity than the same-sized COD crystals. Both apoptosis and necrosis could lead to mitochondria depolarization and elevate the expression of OPN and the generation of lipid peroxidation product MDA. The amount of expressed OPN and generated MDA was positively related to cell injury degree. The physicochemical properties of crystals could affect the cell death mode. The results of this study may provide a basis for future studies on cell death mechanisms. PMID:27551481

  9. Cell death and cytokine production induced by autoimmunogenic hydrocarbon oils.

    PubMed

    Herman, Sonja; Kny, Angelika; Schorn, Christine; Pfatschbacher, Jürgen; Niederreiter, Birgit; Herrmann, Martin; Holmdahl, Rikard; Steiner, Günter; Hoffmann, Markus H

    2012-12-01

    Hydrocarbon oils such as pristane or hexadecane induce arthritis and lupus in rodents sharing clinical and pathological features with the human diseases rheumatoid arthritis and systemic lupus erythematosus, respectively. In pristane-induced lupus in the mouse induction of apoptosis and augmentation of type-I Interferon signalling by pristane have been suggested to contribute to pathology, whereas in pristane-induced arthritis (PIA) in the rat the pathological mechanisms are still elusive. Here we show that pristane induces cell death in rat and human cells. Increased numbers of apoptotic cells were found in draining lymph nodes of pristane-injected rats and increased percentages of apoptotic and necrotic cells were observed in peripheral blood. In addition, neutrophil extracellular trap formation was triggered by pristane and hexadecane in neutrophils. Because levels of interleukin (IL)-1β were elevated in sera of pristane-injected rats, with levels mirroring the course of PIA, we examined the effect of pristane at single cell level in vitro, using rat splenocytes and the human monocytic cell line THP-1. Pristane and other hydrocarbon oils induced IL-1β secretion in THP-1 cells as well as in rat splenocytes. The potassium channel inhibitor glibenclamide partly inhibited IL-1β induction, suggesting involvement of the inflammasome. Elevated levels of IL-1α were also found in supernatants of cells treated with pristane and hexadecane. In conclusion, autoimmunogenic hydrocarbon oils induce various forms of cell death in rat and human cells. The higher serum IL-1β levels in pristane-injected animals might be caused by both inflammasome-dependent and -independent mechanisms, such as passive release from dying-cells and probably extracellular maturation of pro-IL-1β. PMID:22917079

  10. Cell birth, cell death, cell diversity and DNA breaks: how do they all fit together?

    NASA Technical Reports Server (NTRS)

    Gilmore, E. C.; Nowakowski, R. S.; Caviness, V. S. Jr; Herrup, K.

    2000-01-01

    Substantial death of migrating and differentiating neurons occurs within the developing CNS of mice that are deficient in genes required for repair of double-stranded DNA breaks. These findings suggest that large-scale, yet previously unrecognized, double-stranded DNA breaks occur normally in early postmitotic and differentiating neurons. Moreover, they imply that cell death occurs if the breaks are not repaired. The cause and natural function of such breaks remains a mystery; however, their occurrence has significant implications. They might be detected by histological methods that are sensitive to DNA fragmentation and mistakenly interpreted to indicate cell death when no relationship exists. In a broader context, there is now renewed speculation that DNA recombination might be occurring during neuronal development, similar to DNA recombination in developing lymphocytes. If this is true, the target gene(s) of recombination and their significance remain to be determined.

  11. The variability of autophagy and cell death susceptibility

    PubMed Central

    Loos, Ben; Engelbrecht, Anna-Mart; Lockshin, Richard A.; Klionsky, Daniel J; Zakeri, Zahra

    2013-01-01

    Impaired autophagic machinery is implicated in a number of diseases such as heart disease, neurodegeneration and cancer. A common denominator in these pathologies is a dysregulation of autophagy that has been linked to a change in susceptibility to cell death. Although we have progressed in understanding the molecular machinery and regulation of the autophagic pathway, many unanswered questions remain. How does the metabolic contribution of autophagy connect with the cell’s history and how does its current autophagic flux affect metabolic status and susceptibility to undergo cell death? How does autophagic flux operate to switch metabolic direction and what are the underlying mechanisms in metabolite and energetic sensing, metabolite substrate provision and metabolic integration during the cellular stress response? In this article we focus on unresolved questions that address issues around the role of autophagy in sensing the energetic environment and its role in actively generating metabolite substrates. We attempt to provide answers by explaining how and when a change in autophagic pathway activity such as primary stress response is able to affect cell viability and when not. By addressing the dynamic metabolic relationship between autophagy, apoptosis and necrosis we provide a new perspective on the parameters that connect autophagic activity, severity of injury and cellular history in a logical manner. Last, by evaluating the cell’s condition and autophagic activity in a clear context of regulatory parameters in the intra- and extracellular environment, this review provides new concepts that set autophagy into an energetic feedback loop, that may assist in our understanding of autophagy in maintaining healthy cells or when it controls the threshold between cell death and cell survival. PMID:23846383

  12. Thymoquinone causes multiple effects, including cell death, on dividing plant cells.

    PubMed

    Hassanien, Sameh E; Ramadan, Ahmed M; Azeiz, Ahmed Z Abdel; Mohammed, Rasha A; Hassan, Sabah M; Shokry, Ahmed M; Atef, Ahmed; Kamal, Khalid B H; Rabah, Samar; Sabir, Jamal S M; Abuzinadah, Osama A; El-Domyati, Fotouh M; Martin, Gregory B; Bahieldin, Ahmed

    2013-01-01

    Thymoquinone (TQ) is a major constituent of Nigella sativa oil with reported anti-oxidative activity and anti-inflammatory activity in animal cells. It also inhibits proliferation and induces programmed cell death (apoptosis) in human skin cancer cells. The present study sought to detect the influence of TQ on dividing cells of three plant systems and on expression of Bcl2-associated athanogene-like (BAG-like) genes that might be involved during the process of cell death. BAG genes are known for the regulation of diverse physiological processes in animals, including apoptosis, tumorigenesis, stress responses, and cell division. Synthetic TQ at 0.1mg/mL greatly reduced wheat seed germination rate, whereas 0.2mg/mL completely inhibited germination. An Evans blue assay revealed moderate cell death in the meristematic zone of Glycine max roots after 1h of TQ treatment (0.2mg/mL), with severe cell death occurring in this zone after 2h of treatment. Light microscopy of TQ-treated (0.2mg/mL) onion hairy root tips for 1h revealed anti-mitotic activity and also cell death-associated changes, including nuclear membrane disruption and nuclear fragmentation. Transmission electron microscopy of TQ-treated cells (0.2mg/mL) for 1h revealed shrinkage of the plasma membrane, leakage of cell lysate, degradation of cell walls, enlargement of vacuoles and condensation of nuclei. Expression of one BAG-like gene, previously associated with cell death, was induced 20 min after TQ treatment in Glycine max root tip cells. Thus, TQ has multiple effects, including cell death, on dividing plant cells and plants may serve as a useful system to further investigate the mechanisms underlying the response of eukaryotic cells to TQ. PMID:24296078

  13. Cell Cycle-Dependent Mechanisms Underlie Vincristine-Induced Death of Primary Acute Lymphoblastic Leukemia Cells.

    PubMed

    Kothari, Anisha; Hittelman, Walter N; Chambers, Timothy C

    2016-06-15

    Microtubule-targeting agents (MTA), such as the taxanes and vinca alkaloids, are used to treat a variety of cancers due to their ability to perturb microtubule dynamics. In cell culture, MTAs exert their anticancer effects primarily by causing mitotic arrest and cell death. However, accumulating indirect evidence suggests that MTAs may exert their cytotoxicity in human tumors by interfering with interphase microtubules. In this study, we sought to develop and characterize an experimental system in which to test the hypothesis that MTAs induce cell death during interphase. Primary adult acute lymphoblastic leukemia (ALL) cells treated with vincristine only weakly exhibited colocalization between mitotic and apoptotic markers and major characteristics of mitotic death, such as an increase in cells with 4N DNA content before the appearance of cells with <2N DNA content, suggesting a mixed response. Therefore, we separated ALL cells into distinct phases of the cell cycle by centrifugal elutriation, labeled cells with 5-ethynyl-2'-deoxyuridine (EdU), and then treated each population with vincristine. Cells isolated during G1 underwent cell death without evidence of EdU uptake, indicating that the cytotoxic effects of vincristine took place during G1 Conversely, cells isolated during S or G2-M phases underwent death following mitotic arrest. Thus, vincristine induces distinct death programs in primary ALL cells depending on cell-cycle phase, and cells in G1 are particularly susceptible to perturbation of interphase microtubules. Primary ALL cells may therefore provide a powerful model system in which to study the multimodal mechanisms underlying MTA-induced cell death. Cancer Res; 76(12); 3553-61. ©2016 AACR. PMID:27197148

  14. Sudden death of a patient with pulmonary Langerhans cell histiocytosis.

    PubMed

    Nakhla, Hassan; Jumbelic, Mary I

    2005-06-01

    We report a case of sudden death due to bilateral pneumothorax in a previously healthy 16-year-old adolescent white girl. She presented with sudden onset of shortness of breath followed by loss of consciousness. Postmortem chest radiograph showed bilateral pneumothoraces. Autopsy confirmed the bilateral pneumothorax and additionally showed emphysematous changes and bullae throughout the lung tissue. Microscopic sections of the lungs showed Langerhans cell histiocytosis. To the best of our knowledge, this is the first reported case of fatal presentation of pulmonary Langerhans cell histiocytosis. PMID:15913433

  15. Low zinc environment induces stress signaling, senescence and mixed cell death modalities in colon cancer cells.

    PubMed

    Rudolf, Emil; Rudolf, Kamil

    2015-12-01

    Currently it is not clear what type of the final cellular response (i.e. cell death modality or senescence) is induced upon chronic intracellular zinc depletion in colon cancer cells. To address this question, isogenic colon cancer lines SW480 and SW620 exposed to low zinc environment were studied over the period of 6 weeks. Low zinc environment reduced total as well as free intracellular zinc content in both cell lines. Decreased intracellular zinc content resulted in changes in cellular proliferation, cell cycle distribution and activation of stress signaling. In addition, colonocytes with low zinc content displayed increased levels of oxidative stress, changes in mitochondrial activity but in the absence of significant DNA damage. Towards the end of treatment (4th-6th week), exposed cells started to change morphologically, and typical markers of senescence as well as cell death appeared. Of two examined colon cancer cell lines, SW480 cells proved to activate predominantly senescent phenotype, with frequent form of demise being necrosis and mixed cell death modality but not apoptosis. Conversely, SW620 cells activated mostly cell death, with relatively equal distribution of apoptosis and mixed types, while senescent phenotypes and necrosis were present only in a small fraction of cell populations. Addition of zinc at the beginning of 4th week of treatment significantly suppressed cell death phenotypes in both cell lines but had no significant effect on senescence. In conclusion, presented results demonstrate variability of responses to chronic zinc depletion in colon cancer as modeled in vitro. PMID:26446979

  16. EFFECTS OF ETHANOL AND HYDROGEN PEROXIDE ON MOUSE LIMB BUD MESENCHYME DIFFERENTIATION AND CELL DEATH

    EPA Science Inventory

    Many of the morphological defects associated with embryonic alcohol exposure are a result of cell death. During limb development, ethanol administration produces cell death in the limb and digital defects, including postaxial ectrodactyly. Because an accumulation of reactive oxyg...

  17. Cell death stages in single apoptotic and necrotic cells monitored by Raman microspectroscopy

    PubMed Central

    Brauchle, Eva; Thude, Sibylle; Brucker, Sara Y.; Schenke-Layland, Katja

    2014-01-01

    Although apoptosis and necrosis have distinct features, the identification and discrimination of apoptotic and necrotic cell death in vitro is challenging. Immunocytological and biochemical assays represent the current gold standard for monitoring cell death pathways; however, these standard assays are invasive, render large numbers of cells and impede continuous monitoring experiments. In this study, both room temperature (RT)-induced apoptosis and heat-triggered necrosis were analyzed in individual Saos-2 and SW-1353 cells by utilizing Raman microspectroscopy. A targeted analysis of defined cell death modalities, including early and late apoptosis as well as necrosis, was facilitated based on the combination of Raman spectroscopy with fluorescence microscopy. Spectral shifts were identified in the two cell lines that reflect biochemical changes specific for either RT-induced apoptosis or heat-mediated necrosis. A supervised classification model specified apoptotic and necrotic cell death based on single cell Raman spectra. To conclude, Raman spectroscopy allows a non-invasive, continuous monitoring of cell death, which may help shedding new light on complex pathophysiological or drug-induced cell death processes. PMID:24732136

  18. Cell death stages in single apoptotic and necrotic cells monitored by Raman microspectroscopy

    NASA Astrophysics Data System (ADS)

    Brauchle, Eva; Thude, Sibylle; Brucker, Sara Y.; Schenke-Layland, Katja

    2014-04-01

    Although apoptosis and necrosis have distinct features, the identification and discrimination of apoptotic and necrotic cell death in vitro is challenging. Immunocytological and biochemical assays represent the current gold standard for monitoring cell death pathways; however, these standard assays are invasive, render large numbers of cells and impede continuous monitoring experiments. In this study, both room temperature (RT)-induced apoptosis and heat-triggered necrosis were analyzed in individual Saos-2 and SW-1353 cells by utilizing Raman microspectroscopy. A targeted analysis of defined cell death modalities, including early and late apoptosis as well as necrosis, was facilitated based on the combination of Raman spectroscopy with fluorescence microscopy. Spectral shifts were identified in the two cell lines that reflect biochemical changes specific for either RT-induced apoptosis or heat-mediated necrosis. A supervised classification model specified apoptotic and necrotic cell death based on single cell Raman spectra. To conclude, Raman spectroscopy allows a non-invasive, continuous monitoring of cell death, which may help shedding new light on complex pathophysiological or drug-induced cell death processes.

  19. Role of mitochondrial function in cell death and body metabolism.

    PubMed

    Lee, Myung-Shik

    2016-01-01

    Mitochondria are the key players in apoptosis and necrosis. Mitochondrial DNA (mtDNA)-depleted r0 cells were resistant to diverse apoptosis inducers such as TNF-alpha, TNFSF10, staurosporine and p53. Apoptosis resistance was accompanied by the absence of mitochondrial potential loss or cytochrome c translocation. r0 cells were also resistant to necrosis induced by reactive oxygen species (ROS) donors due to upregulation of antioxidant enzymes such as manganese superoxide dismutase. Mitochondria also has a close relationship with autophagy that plays a critical role in the turnover of senescent organelles or dysfunctional proteins and may be included in 'cell death' category. It was demonstrated that autophagy deficiency in insulin target tissues such as skeletal muscle induces mitochondrial stress response, which leads to the induction of FGF21 as a 'mitokine' and affects the whole body metabolism. These results show that mitochondria are not simply the power plants of cells generating ATP, but are closely related to several types of cell death and autophagy. Mitochondria affect various pathophysiological events related to diverse disorders such as cancer, metabolic disorders and aging. PMID:27100503

  20. Molecular mechanisms of Ebola virus pathogenesis: focus on cell death.

    PubMed

    Falasca, L; Agrati, C; Petrosillo, N; Di Caro, A; Capobianchi, M R; Ippolito, G; Piacentini, M

    2015-08-01

    Ebola virus (EBOV) belongs to the Filoviridae family and is responsible for a severe disease characterized by the sudden onset of fever and malaise accompanied by other non-specific signs and symptoms; in 30-50% of cases hemorrhagic symptoms are present. Multiorgan dysfunction occurs in severe forms with a mortality up to 90%. The EBOV first attacks macrophages and dendritic immune cells. The innate immune reaction is characterized by a cytokine storm, with secretion of numerous pro-inflammatory cytokines, which induces a huge number of contradictory signals and hurts the immune cells, as well as other tissues. Other highly pathogenic viruses also trigger cytokine storms, but Filoviruses are thought to be particularly lethal because they affect a wide array of tissues. In addition to the immune system, EBOV attacks the spleen and kidneys, where it kills cells that help the body to regulate its fluid and chemical balance and that make proteins that help the blood to clot. In addition, EBOV causes liver, lungs and kidneys to shut down their functions and the blood vessels to leak fluid into surrounding tissues. In this review, we analyze the molecular mechanisms at the basis of Ebola pathogenesis with a particular focus on the cell death pathways induced by the virus. We also discuss how the treatment of the infection can benefit from the recent experience of blocking/modulating cell death in human degenerative diseases. PMID:26024394

  1. Programmed Cell Death Initiation and Execution in Budding Yeast

    PubMed Central

    Strich, Randy

    2015-01-01

    Apoptosis or programmed cell death (PCD) was initially described in metazoans as a genetically controlled process leading to intracellular breakdown and engulfment by a neighboring cell . This process was distinguished from other forms of cell death like necrosis by maintenance of plasma membrane integrity prior to engulfment and the well-defined genetic system controlling this process. Apoptosis was originally described as a mechanism to reshape tissues during development. Given this context, the assumption was made that this process would not be found in simpler eukaryotes such as budding yeast. Although basic components of the apoptotic pathway were identified in yeast, initial observations suggested that it was devoid of prosurvival and prodeath regulatory proteins identified in mammalian cells. However, as apoptosis became extensively linked to the elimination of damaged cells, key PCD regulatory proteins were identified in yeast that play similar roles in mammals. This review highlights recent discoveries that have permitted information regarding PCD regulation in yeast to now inform experiments in animals. PMID:26272996

  2. Molecular mechanisms of Ebola virus pathogenesis: focus on cell death

    PubMed Central

    Falasca, L; Agrati, C; Petrosillo, N; Di Caro, A; Capobianchi, M R; Ippolito, G; Piacentini, M

    2015-01-01

    Ebola virus (EBOV) belongs to the Filoviridae family and is responsible for a severe disease characterized by the sudden onset of fever and malaise accompanied by other non-specific signs and symptoms; in 30–50% of cases hemorrhagic symptoms are present. Multiorgan dysfunction occurs in severe forms with a mortality up to 90%. The EBOV first attacks macrophages and dendritic immune cells. The innate immune reaction is characterized by a cytokine storm, with secretion of numerous pro-inflammatory cytokines, which induces a huge number of contradictory signals and hurts the immune cells, as well as other tissues. Other highly pathogenic viruses also trigger cytokine storms, but Filoviruses are thought to be particularly lethal because they affect a wide array of tissues. In addition to the immune system, EBOV attacks the spleen and kidneys, where it kills cells that help the body to regulate its fluid and chemical balance and that make proteins that help the blood to clot. In addition, EBOV causes liver, lungs and kidneys to shut down their functions and the blood vessels to leak fluid into surrounding tissues. In this review, we analyze the molecular mechanisms at the basis of Ebola pathogenesis with a particular focus on the cell death pathways induced by the virus. We also discuss how the treatment of the infection can benefit from the recent experience of blocking/modulating cell death in human degenerative diseases. PMID:26024394

  3. The essential role of evasion from cell death in cancer.

    PubMed

    Kelly, Gemma L; Strasser, Andreas

    2011-01-01

    The link between evasion of apoptosis and the development of cellular hyperplasia and ultimately cancer is implicitly clear if one considers how many cells are produced each day and, hence, how many cells must die to make room for the new ones (reviewed in Raff, 1996). Furthermore, cells are frequently experiencing noxious stimuli that can cause lesions in their DNA and faults in DNA replication can occur during cellular proliferation. Such DNA damage needs to be repaired efficiently or cells with irreparable damage must be killed to prevent subsequent division of aberrant cells that may fuel tumorigenesis (reviewed in Weinberg, 2007). The detection of genetic lesions in human cancers that activate prosurvival genes or disable proapoptotic genes have provided the first evidence that defects in programmed cell death can cause cancer (Tagawa et al., 2005; Tsujimoto et al., 1984; Vaux, Cory, and Adams, 1988) and this concept was proven by studies with genetically modified mice (Egle et al., 2004b; Strasser et al., 1990a). It is therefore now widely accepted that evasion of apoptosis is a requirement for both neoplastic transformation and sustained growth of cancer cells (reviewed in Cory and Adams, 2002; Hanahan and Weinberg, 2000; Weinberg, 2007). Importantly, apoptosis is also a major contributor to anticancer therapy-induced killing of tumor cells (reviewed in Cory and Adams, 2002; Cragg et al., 2009). Consequently, a detailed understanding of apoptotic cell death will help to better comprehend the complexities of tumorigenesis and should assist with the development of improved targeted therapies for cancer based on the direct activation of the apoptotic machinery (reviewed in Lessene, Czabotar, and Colman, 2008). PMID:21704830

  4. Cell Death Control by Matrix Metalloproteinases1[OPEN

    PubMed Central

    Zimmermann, Dirk; Sieferer, Elke; Pfannstiel, Jens

    2016-01-01

    In contrast to mammalian matrix metalloproteinases (MMPs) that play important roles in the remodeling of the extracellular matrix in animals, the proteases responsible for dynamic modifications of the plant cell wall are largely unknown. A possible involvement of MMPs was addressed by cloning and functional characterization of Sl2-MMP and Sl3-MMP from tomato (Solanum lycopersicum). The two tomato MMPs were found to resemble mammalian homologs with respect to gelatinolytic activity, substrate preference for hydrophobic amino acids on both sides of the scissile bond, and catalytic properties. In transgenic tomato seedlings silenced for Sl2/3-MMP expression, necrotic lesions were observed at the base of the hypocotyl. Cell death initiated in the epidermis and proceeded to include outer cortical cell layers. In later developmental stages, necrosis spread, covering the entire stem and extending into the leaves of MMP-silenced plants. The subtilisin-like protease P69B was identified as a substrate of Sl2- and Sl3-MMP. P69B was shown to colocalize with Sl-MMPs in the apoplast of the tomato hypocotyl, it exhibited increased stability in transgenic plants silenced for Sl-MMP activity, and it was cleaved and inactivated by Sl-MMPs in vitro. The induction of cell death in Sl2/3-MMP-silenced plants depended on P69B, indicating that Sl2- and Sl3-MMP act upstream of P69B in an extracellular proteolytic cascade that contributes to the regulation of cell death in tomato. PMID:27208293

  5. The pantheon of the fallen: why are there so many forms of cell death?

    PubMed

    Green, Douglas R; Victor, Bernadette

    2012-11-01

    Cells die by various mechanisms, only some of which have been elucidated in detail. Numerous 'active' forms of cell death exist in which the cell participates in its own death, including apoptosis, programmed necrosis, mitotic catastrophe, and the recently described ferroptosis. Here, we attempt to explain why there are so many different forms of cell death, and propose a distinction between active death that constitutes 'suicide' versus 'sabotage'. PMID:22995729

  6. Autophagy Protects Against Aminochrome-Induced Cell Death in Substantia Nigra-Derived Cell Line

    PubMed Central

    Paris, Irmgard; Muñoz, Patricia; Huenchuguala, Sandro; Couve, Eduardo; Sanders, Laurie H.; Greenamyre, John Timothy; Caviedes, Pablo; Segura-Aguilar, Juan

    2011-01-01

    Aminochrome, the precursor of neuromelanin, has been proposed to be involved in the neurodegeneration neuromelanin-containing dopaminergic neurons in Parkinson’s disease. We aimed to study the mechanism of aminochrome-dependent cell death in a cell line derived from rat substantia nigra. We found that aminochrome (50μM), in the presence of NAD(P)H-quinone oxidoreductase, EC 1.6.99.2 (DT)-diaphorase inhibitor dicoumarol (DIC) (100μM), induces significant cell death (62 ± 3%; p < 0.01), increase in caspase-3 activation (p < 0.001), release of cytochrome C, disruption of mitochondrial membrane potential (p < 0.01), damage of mitochondrial DNA, damage of mitochondria determined with transmission electron microscopy, a dramatic morphological change characterized as cell shrinkage, and significant increase in number of autophagic vacuoles. To determine the role of autophagy on aminochrome-induced cell death, we incubated the cells in the presence of vinblastine and rapamycin. Interestingly, 10μM vinblastine induces a 5.9-fold (p < 0.001) and twofold (p < 0.01) significant increase in cell death when the cells were incubated with 30μM aminochrome in the absence and presence of DIC, respectively, whereas 10μM rapamycin preincubated 24 h before addition of 50μM aminochrome in the absence and the presence of 100μM DIC induces a significant decrease (p < 0.001) in cell death. In conclusion, autophagy seems to be an important protective mechanism against two different aminochrome-induced cell deaths that initially showed apoptotic features. The cell death induced by aminochrome when DT-diaphorase is inhibited requires activation of mitochondrial pathway, whereas the cell death induced by aminochrome alone requires inhibition of autophagy-dependent degrading of damaged organelles and recycling through lysosomes. PMID:21427056

  7. Necdin Protects Embryonic Motoneurons from Programmed Cell Death

    PubMed Central

    Aebischer, Julianne; Sturny, Rachel; Andrieu, David; Rieusset, Anne; Schaller, Fabienne; Geib, Sandrine; Raoul, Cédric; Muscatelli, Françoise

    2011-01-01

    NECDIN belongs to the type II Melanoma Associated Antigen Gene Expression gene family and is located in the Prader-Willi Syndrome (PWS) critical region. Necdin-deficient mice develop symptoms of PWS, including a sensory and motor deficit. However, the mechanisms underlying the motor deficit remain elusive. Here, we show that the genetic ablation of Necdin, whose expression is restricted to post-mitotic neurons in the spinal cord during development, leads to a loss of 31% of specified motoneurons. The increased neuronal loss occurs during the period of naturally-occurring cell death and is not confined to specific pools of motoneurons. To better understand the role of Necdin during the period of programmed cell death of motoneurons we used embryonic spinal cord explants and primary motoneuron cultures from Necdin-deficient mice. Interestingly, while Necdin-deficient motoneurons present the same survival response to neurotrophic factors, we demonstrate that deletion of Necdin leads to an increased susceptibility of motoneurons to neurotrophic factor deprivation. We show that by neutralizing TNFα this increased susceptibility of Necdin-deficient motoneurons to trophic factor deprivation can be reduced to the normal level. We propose that Necdin is implicated through the TNF-receptor 1 pathway in the developmental death of motoneurons. PMID:21912643

  8. The fibrosis-cell death axis in heart failure.

    PubMed

    Piek, A; de Boer, R A; Silljé, H H W

    2016-03-01

    Cardiac stress can induce morphological, structural and functional changes of the heart, referred to as cardiac remodeling. Myocardial infarction or sustained overload as a result of pathological causes such as hypertension or valve insufficiency may result in progressive remodeling and finally lead to heart failure (HF). Whereas pathological and physiological (exercise, pregnancy) overload both stimulate cardiomyocyte growth (hypertrophy), only pathological remodeling is characterized by increased deposition of extracellular matrix proteins, termed fibrosis, and loss of cardiomyocytes by necrosis, apoptosis and/or phagocytosis. HF is strongly associated with age, and cardiomyocyte loss and fibrosis are typical signs of the aging heart. Fibrosis results in stiffening of the heart, conductivity problems and reduced oxygen diffusion, and is associated with diminished ventricular function and arrhythmias. As a consequence, the workload of cardiomyocytes in the fibrotic heart is further augmented, whereas the physiological environment is becoming less favorable. This causes additional cardiomyocyte death and replacement of lost cardiomyocytes by fibrotic material, generating a vicious cycle of further decline of cardiac function. Breaking this fibrosis-cell death axis could halt further pathological and age-related cardiac regression and potentially reverse remodeling. In this review, we will describe the interaction between cardiac fibrosis, cardiomyocyte hypertrophy and cell death, and discuss potential strategies for tackling progressive cardiac remodeling and HF. PMID:26883434

  9. Combinatorial Strategies for the Induction of Immunogenic Cell Death

    PubMed Central

    Bezu, Lucillia; Gomes-da-Silva, Ligia C.; Dewitte, Heleen; Breckpot, Karine; Fucikova, Jitka; Spisek, Radek; Galluzzi, Lorenzo; Kepp, Oliver; Kroemer, Guido

    2015-01-01

    The term “immunogenic cell death” (ICD) is commonly employed to indicate a peculiar instance of regulated cell death (RCD) that engages the adaptive arm of the immune system. The inoculation of cancer cells undergoing ICD into immunocompetent animals elicits a specific immune response associated with the establishment of immunological memory. Only a few agents are intrinsically endowed with the ability to trigger ICD. These include a few chemotherapeutics that are routinely employed in the clinic, like doxorubicin, mitoxantrone, oxaliplatin, and cyclophosphamide, as well as some agents that have not yet been approved for use in humans. Accumulating clinical data indicate that the activation of adaptive immune responses against dying cancer cells is associated with improved disease outcome in patients affected by various neoplasms. Thus, novel therapeutic regimens that trigger ICD are urgently awaited. Here, we discuss current combinatorial approaches to convert otherwise non-immunogenic instances of RCD into bona fide ICD. PMID:25964783

  10. Death and survival of heterozygous Lurcher Purkinje cells in vitro

    PubMed Central

    Zanjani, Hadi; McFarland, Rebecca; Cavelier, Pauline; Blokhin, Andrei; Gautheron, Vanessa; Levenes, Carole; Bambrick, Linda L.; Mariani, Jean; Vogel, Michael W.

    2009-01-01

    The differentiation and survival of heterozygous Lurcher (+/Lc) Purkinje cells in vitro was examined as a model system for studying how chronic ionic stress affects neuronal differentiation and survival. The Lurcher mutation in the δ2 glutamate receptor (GluRδ2) converts an orphan receptor into a membrane channel that constitutively passes an inward cation current. In the GluRδ2+/Lc mutant, Purkinje cell dendritic differentiation is disrupted and the cells degenerate following the first week of postnatal development. To determine if the GluRδ2+/Lc Purkinje cell phenotype is recapitulated in vitro, +/+ and +/Lc Purkinje cells from postnatal day 0 pups were grown in either isolated cell or cerebellar slice cultures. GluRδ2+/+ and GluRδ2+/Lc Purkinje cells appeared to develop normally through the first 7 days in vitro (DIV), but by 11 DIV GluRδ2+/Lc Purkinje cells exhibited a significantly higher cation leak current. By 14 DIV, GluRδ2+/Lc Purkinje cell dendrites were stunted and the number of surviving GluRδ2+/Lc Purkinje cells was reduced by 75% compared to controls. However, treatment of +/Lc cerebellar cultures with 1-naphthyl acetyl spermine (NASP) increased +/Lc Purkinje cell survival to wild type levels. These results support the conclusion that the Lurcher mutation in GluRδ2 induces cell autonomous defects in differentiation and survival. The establishment of a tissue culture system for studying cell injury and death mechanisms in a relatively simple system like GluRδ2+/Lc Purkinje cells will provide a valuable model for studying how the induction of a chronic inward cation current in a single cell type affects neuronal differentiation and survival. PMID:19294643