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  1. Cholecystokinin expression in the β-cell leads to increased β-cell area in aged mice and protects from streptozotocin-induced diabetes and apoptosis.

    Science.gov (United States)

    Lavine, Jeremy A; Kibbe, Carly R; Baan, Mieke; Sirinvaravong, Sirinart; Umhoefer, Heidi M; Engler, Kimberly A; Meske, Louise M; Sacotte, Kaitlyn A; Erhardt, Daniel P; Davis, Dawn Belt

    2015-11-15

    Cholecystokinin (CCK) is a peptide hormone produced in the gut and brain with beneficial effects on digestion, satiety, and insulin secretion. CCK is also expressed in pancreatic β-cells, but only in models of obesity and insulin resistance. Whole body deletion of CCK in obese mice leads to reduced β-cell mass expansion and increased apoptosis. We hypothesized that islet-derived CCK is important in protection from β-cell apoptosis. To determine the specific role of β-cell-derived CCK in β-cell mass dynamics, we generated a transgenic mouse that expresses CCK in the β-cell in the lean state (MIP-CCK). Although this transgene contains the human growth hormone minigene, we saw no expression of human growth hormone protein in transgenic islets. We examined the ability of MIP-CCK mice to maintain β-cell mass when subjected to apoptotic stress, with advanced age, and after streptozotocin treatment. Aged MIP-CCK mice have increased β-cell area. MIP-CCK mice are resistant to streptozotocin-induced diabetes and exhibit reduced β-cell apoptosis. Directed CCK overexpression in cultured β-cells also protects from cytokine-induced apoptosis. We have identified an important new paracrine/autocrine effect of CCK in protection of β-cells from apoptotic stress. Understanding the role of β-cell CCK adds to the emerging knowledge of classic gut peptides in intraislet signaling. CCK receptor agonists are being investigated as therapeutics for obesity and diabetes. While these agonists clearly have beneficial effects on body weight and insulin sensitivity in peripheral tissues, they may also directly protect β-cells from apoptosis.

  2. Description of morphological changes in neurons and endothelial cells of CA1-area of hippocampus in rats with alloxan-induced hyp erglycemia under application of nootropic drugs

    Directory of Open Access Journals (Sweden)

    Zhylyuk V.I.

    2012-01-01

    Full Text Available Using neuromorphometry analysis differences in the effects of nootropic drugs on morphology and function of neurons and endothelial cells of hippocampus, content of RNA, content of apoptotic and destructive neurons were examined in white rats with chronic alloxan-induced hyperglycemia. It ha s been found that diabetes in rats is accompanied by specific morphological and functional changes and activation of apoptosis in neurons of the CA1-area in hi ppocampus, which may be related to disturbance of local blood flow due to endothelial damage. N-carbamoyl-methyl-4-phenyl-2-pyrrolidone (entrop, N-phenylacetyl-L-prolylglycine (noopept, pramiracetam, cerebrocurin and citicoline show protective effects on neurons and endothelial cells, which are much larger in force than effect s of ginkgo biloba extract, piracetam and pentoxifylline. This protective activity is characterized by reducing the number of apoptotic and dest ructive neurons in hippocampal CA1-area, increasing the density of functioning nerve and endothelial cells, activation of RNA biosynthesis in the neurocytes and endo-thelial cells

  3. Induced pluripotent stem cells

    Institute of Scientific and Technical Information of China (English)

    Siddhartha Bhowmik; LI Yong

    2011-01-01

    Induced pluripotent stem (iPS) cells are a recent development which has brought a promise of great therapeutic values. The previous technique of somatic cell nuclear transfer (SCNT) has been ineffective in humans. Recent discoveries show that human fibroblasts can be reprogrammed by a transient over expression of a small number of genes; they can undergo induced pluripotency. iPS were first produced in 2006. By 2008, work was underway to remove the potential oncogenes from their structure. In 2009, protein iPS (piPS) cells were discovered. Surface markers and reporter genes play an important role in stem cell research. Clinical applications include generation of self renewing stem cells, tissue replacement and many more. Stem cell therapy has the ability to dramatically change the treatment of human diseases.

  4. An induced junction photovoltaic cell

    Science.gov (United States)

    Call, R. L.

    1974-01-01

    Silicon solar cells operating with induced junctions rather than diffused junctions have been fabricated and tested. Induced junctions were created by forming an inversion layer near the surface of the silicon by supplying a sheet of positive charge above the surface. Measurements of the response of the inversion layer cell to light of different wavelengths indicated it to be more sensitive to the shorter wavelengths of the sun's spectrum than conventional cells. The greater sensitivity occurs because of the shallow junction and the strong electric field at the surface.

  5. Large area perovskite solar cell module

    Science.gov (United States)

    Cai, Longhua; Liang, Lusheng; Wu, Jifeng; Ding, Bin; Gao, Lili; Fan, Bin

    2017-01-01

    The recent dramatic rise in power conversion efficiencies (PCE) of perovskite solar cells has triggered intense research worldwide. However, their practical development is hampered by poor stability and low PCE values with large areas devices. Here, we developed a gas-pumping method to avoid pinholes and eliminate local structural defects over large areas of perovskite film, even for 5 × 5 cm2 modules, the PCE reached 10.6% and no significant degradation was found after 140 days of outdoor testing. Our approach enables the realization of high performance large-area PSCs for practical application.

  6. Interaction of cambial dermal cells (fibroblasts) and epidermis in morphofunctional area of mouse skin.

    Science.gov (United States)

    Yavisheva, T M; Shcherbakov, S D; Golubeva, I S; Sharafutdinov, G Z

    2007-11-01

    Epidermis and dermis form an integral morphofunctional area, where cambial cells proliferate and their first-division daughter cells differentiate. An important feature of this area is different rates of the development of daughter cells (fibroblasts) in the dermis and epidermis, which is greater in the epidermis. This asymmetry results in the prevalence of first epidermal daughter cells and, hence, their effect on cambial cells, and then of stromal daughter cells and their effects on cambial cells. The regulator factors of epidermal daughter cells promote unblocking of the major polarity axis of cambial (mother) cell, while stromal cells (fibroblasts) induce their polarization along the major axis and the onset of mitosis. In the dermis and epidermis, division of cambial cells is asymmetric; a prominent role in the formation of mother and daughter cells is given to the basal membrane as an elastic support. Mother and daughter cells form ring-like structures generating electric field that can promote differentiation of the daughter cells.

  7. HIV transcription is induced in dying cells

    Energy Technology Data Exchange (ETDEWEB)

    Woloschak, G.E.; Chang-Liu, Chin-Mei [Argonne National Lab., IL (United States); Schreck, S. [Argonne National Lab., IL (United States)]|[Univ. of South Carolina, Columbia, SC (United States). Dept. of Chemistry; Panozzo, J. [Loyola Univ. Medical Center, Maywood, IL (United States); Libertin, C.R. [Loyola Univ. Medical Center, Maywood, IL (United States)

    1996-02-01

    Using HeLa cells stably transfected with an HIV-LTR-CAT construct, we demonstrated a peak in CAT induction that occurs in viable (but not necessarily cell-division-competent) cells 24 h following exposure to some cell-killing agents. {gamma} rays were the only cell-killing agent which did not induce HIV transcription; this can be attributed to the fact that {gamma}-ray-induced apoptotic death requires functional p53, which is not present in HeLa cells. For all other agents, HIV-LTR induction was dose-dependent and correlated with the amount of cell killing that occurred in the culture. Doses which caused over 99% cell killing induced HIV-LTR transcription maximally, demonstrating that cells that will go on to die by 14 days are the cells expressing HIV-LTR-CAT.

  8. Metformin induces apoptosis of pancreatic cancer cells

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

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

  9. Fish Stem Cells: Classification, Resources, Characteristics and Application Areas

    Directory of Open Access Journals (Sweden)

    Şehriban ÇEK

    2016-08-01

    Full Text Available Stem cells are a class of undifferentiated cells, have the potential for self-renewal that can differ to the specialized cells. First studies on stem cells in fish started with zebra fish in 1992. In this review, classification, resources, vital importance, characteristics and application areas of fish stem cell were clarified.

  10. Sodium Accumulation at Potential-Induced Degradation Shunted Areas in Polycrystalline Silicon Modules

    Energy Technology Data Exchange (ETDEWEB)

    Harvey, Steven P.; Aguiar, Jeffery A.; Hacke, Peter; Guthrey, Harvey; Johnston, Steve; Al-Jassim, Mowafak

    2016-11-01

    We investigated potential-induced degradation (PID) in silicon mini-modules that were subjected to accelerated stressing to induce PID conditions. Shunted areas on the cells were identified with photoluminescence and dark lock-in thermography (DLIT) imaging. The identical shunted areas were then analyzed via time-of-flight secondary-ion mass spectrometry (TOFSIMS) imaging, 3-D tomography, and high-resolution transmission electron microscopy. The TOF-SIMS imaging indicates a high concentration of sodium in the shunted areas, and 3-D tomography reveals that the sodium extends more than 2 um from the surface below shunted regions. Transmission electron microscopy investigation reveals that a stacking fault is present at an area identified as shunted by DLIT imaging. After the removal of surface sodium, tomography reveals persistent sodium present around the junction depth of 300 nm and a drastic difference in sodium content at the junction when comparing shunted and nonshunted regions.

  11. Bend-Induced Distortion in Large Mode Area Holey Fibre

    Institute of Scientific and Technical Information of China (English)

    TAN Xiao-Ling; GENG You-Fu; ZHANG Tie-Li; WANG Wei-Neng; WANG Peng; YAO Jian-Quan

    2008-01-01

    A simplified scheme of bend-induced mode distortion is introduced into bent holey fibres,the distorted mode distribution and mode effective area reduction are investigated using the finite difference method.Numerical results show that the modes of bent holey fibres with small bend radius shift away from the core and are deformed greatly,and the mode areas drop significantly as the bend radius decreases,which severely affects the fibre laser performance.The propagation characteristics of bent holey fibres at given wavelength are determined by fill factor and normalized bend radius.Finally,the transition normalized bend radius that represents the location of the mode area beginning to fall off is obtained.

  12. Induced Pluripotent Stem Cells and Periodontal Regeneration

    OpenAIRE

    Du, Mi; Duan, Xuejing; Yang, Pishan

    2015-01-01

    Periodontitis is a chronic inflammatory disease which leads to destruction of both the soft and hard tissues of the periodontium. Tissue engineering is a therapeutic approach in regenerative medicine that aims to induce new functional tissue regeneration via the synergistic combination of cells, biomaterials, and/or growth factors. Advances in our understanding of the biology of stem cells, including embryonic stem cells and mesenchymal stem cells, have provided opportunities for periodontal ...

  13. Induced pluripotent stem cell lines derived from human somatic cells.

    Science.gov (United States)

    Yu, Junying; Vodyanik, Maxim A; Smuga-Otto, Kim; Antosiewicz-Bourget, Jessica; Frane, Jennifer L; Tian, Shulan; Nie, Jeff; Jonsdottir, Gudrun A; Ruotti, Victor; Stewart, Ron; Slukvin, Igor I; Thomson, James A

    2007-12-21

    Somatic cell nuclear transfer allows trans-acting factors present in the mammalian oocyte to reprogram somatic cell nuclei to an undifferentiated state. We show that four factors (OCT4, SOX2, NANOG, and LIN28) are sufficient to reprogram human somatic cells to pluripotent stem cells that exhibit the essential characteristics of embryonic stem (ES) cells. These induced pluripotent human stem cells have normal karyotypes, express telomerase activity, express cell surface markers and genes that characterize human ES cells, and maintain the developmental potential to differentiate into advanced derivatives of all three primary germ layers. Such induced pluripotent human cell lines should be useful in the production of new disease models and in drug development, as well as for applications in transplantation medicine, once technical limitations (for example, mutation through viral integration) are eliminated.

  14. HIV transcription is induced in dying cells

    Energy Technology Data Exchange (ETDEWEB)

    Woloschak, G.E.; Chang-Liu, Chin-Mei [Argonne National Lab., IL (United States); Schreck, S. [Argonne National Lab., IL (United States)]|[Univ. of South Carolina, Columbia, SC (United States). Dept. of Chemistry

    1995-06-01

    Using HeLa cells stably transfected with an HIV-LTR-CAT construct, we demonstrated a peak in CAT induction that occurs in viable (but not necessarily cell-division-competent) cells 24 h following exposure to some cell-killing agents. {gamma} rays were the only cell-killing agent which did not induce HIV transcription; this can be attributed to the fact that {gamma}-ray-induced apoptotic death requires functional p53, which is not present in HeLa cells. For all other agents, HIV-LTR induction was dose-dependent and correlated with the amount of cell killing that occurred in the culture. 14 refs., 4 figs., 1 tab.

  15. Nuclear area measurement on viable cells, using confocal microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Townsend, K.M.S.; Marsden, S.J. (Medical Research Council, Harwell (United Kingdom). Radiobiological Research Unit)

    1992-04-01

    The authors describe a rapid procedure for the accurate measurement of nuclear areas on unperturbed living cells as used in radiobiological experiments, using the confocal laser scanning microscope. The microdosimetric interpretation of radiobiological data requires precise information on the nuclear area of cells as irradiated with high-LET radiation. (author).

  16. HIF induces human embryonic stem cell markers in cancer cells.

    Science.gov (United States)

    Mathieu, Julie; Zhang, Zhan; Zhou, Wenyu; Wang, Amy J; Heddleston, John M; Pinna, Claudia M A; Hubaud, Alexis; Stadler, Bradford; Choi, Michael; Bar, Merav; Tewari, Muneesh; Liu, Alvin; Vessella, Robert; Rostomily, Robert; Born, Donald; Horwitz, Marshall; Ware, Carol; Blau, C Anthony; Cleary, Michele A; Rich, Jeremy N; Ruohola-Baker, Hannele

    2011-07-01

    Low oxygen levels have been shown to promote self-renewal in many stem cells. In tumors, hypoxia is associated with aggressive disease course and poor clinical outcomes. Furthermore, many aggressive tumors have been shown to display gene expression signatures characteristic of human embryonic stem cells (hESC). We now tested whether hypoxia might be responsible for the hESC signature observed in aggressive tumors. We show that hypoxia, through hypoxia-inducible factor (HIF), can induce an hESC-like transcriptional program, including the induced pluripotent stem cell (iPSC) inducers, OCT4, NANOG, SOX2, KLF4, cMYC, and microRNA-302 in 11 cancer cell lines (from prostate, brain, kidney, cervix, lung, colon, liver, and breast tumors). Furthermore, nondegradable forms of HIFα, combined with the traditional iPSC inducers, are highly efficient in generating A549 iPSC-like colonies that have high tumorigenic capacity. To test potential correlation between iPSC inducers and HIF expression in primary tumors, we analyzed primary prostate tumors and found a significant correlation between NANOG-, OCT4-, and HIF1α-positive regions. Furthermore, NANOG and OCT4 expressions positively correlated with increased prostate tumor Gleason score. In primary glioma-derived CD133 negative cells, hypoxia was able to induce neurospheres and hESC markers. Together, these findings suggest that HIF targets may act as key inducers of a dynamic state of stemness in pathologic conditions.

  17. Mechanisms of ethanol-induced death of cerebellar granule cells.

    Science.gov (United States)

    Luo, Jia

    2012-03-01

    Maternal ethanol exposure during pregnancy may cause fetal alcohol spectrum disorders (FASD). FASD is the leading cause of mental retardation. The most deleterious effect of fetal alcohol exposure is inducing neuroapoptosis in the developing brain. Ethanol-induced loss of neurons in the central nervous system underlies many of the behavioral deficits observed in FASD. The cerebellum is one of the brain areas that are most susceptible to ethanol during development. Ethanol exposure causes a loss of both cerebellar Purkinje cells and granule cells. This review focuses on the toxic effect of ethanol on cerebellar granule cells (CGC) and the underlying mechanisms. Both in vitro and in vivo studies indicate that ethanol induces apoptotic death of CGC. The vulnerability of CGC to ethanol-induced death diminishes over time as neurons mature. Several mechanisms for ethanol-induced apoptosis of CGC have been suggested. These include inhibition of N-methyl-D-aspartate receptors, interference with signaling by neurotrophic factors, induction of oxidative stress, modulation of retinoid acid signaling, disturbance of potassium channel currents, thiamine deficiency, and disruption of translational regulation. Cultures of CGC provide an excellent system to investigate cellular/molecular mechanisms of ethanol-induced neurodegeneration and to evaluate interventional strategies. This review will also discuss the approaches leading to neuroprotection against ethanol-induced neuroapoptosis.

  18. Acetylsalicylic acid induces programmed cell death in Arabidopsis cell cultures.

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    García-Heredia, José M; Hervás, Manuel; De la Rosa, Miguel A; Navarro, José A

    2008-06-01

    Acetylsalicylic acid (ASA), a derivative from the plant hormone salicylic acid (SA), is a commonly used drug that has a dual role in animal organisms as an anti-inflammatory and anticancer agent. It acts as an inhibitor of cyclooxygenases (COXs), which catalyze prostaglandins production. It is known that ASA serves as an apoptotic agent on cancer cells through the inhibition of the COX-2 enzyme. Here, we provide evidences that ASA also behaves as an agent inducing programmed cell death (PCD) in cell cultures of the model plant Arabidopsis thaliana, in a similar way than the well-established PCD-inducing agent H(2)O(2), although the induction of PCD by ASA requires much lower inducer concentrations. Moreover, ASA is herein shown to be a more efficient PCD-inducing agent than salicylic acid. ASA treatment of Arabidopsis cells induces typical PCD-linked morphological and biochemical changes, namely cell shrinkage, nuclear DNA degradation, loss of mitochondrial membrane potential, cytochrome c release from mitochondria and induction of caspase-like activity. However, the ASA effect can be partially reverted by jasmonic acid. Taking together, these results reveal the existence of common features in ASA-induced animal apoptosis and plant PCD, and also suggest that there are similarities between the pathways of synthesis and function of prostanoid-like lipid mediators in animal and plant organisms.

  19. Induced pluripotent stem cells: a new revolution for clinical neurology?

    Science.gov (United States)

    Mattis, Virginia B; Svendsen, Clive N

    2011-04-01

    Why specific neuronal populations are uniquely susceptible in neurodegenerative diseases remains a mystery. Brain tissue samples from patients are rarely available for testing, and animal models frequently do not recapitulate all features of a specific disorder; therefore, pathophysiological investigations are difficult. An exciting new avenue for neurological research and drug development is the discovery that patients' somatic cells can be reprogrammed to a pluripotent state; these cells are known as induced pluripotent stem cells. Once pluripotency is reinstated, cell colonies can be expanded and differentiated into specific neural populations. The availability of these cells enables the monitoring in vitro of temporal features of disease initiation and progression, and testing of new drug treatments on the patient's own cells. Hence, this swiftly growing area of research has the potential to contribute greatly to our understanding of the pathophysiology of neurodegenerative and neurodevelopmental diseases.

  20. Imipramine protects mouse hippocampus against tunicamycin-induced cell death.

    Science.gov (United States)

    Ono, Yoko; Shimazawa, Masamitsu; Ishisaka, Mitsue; Oyagi, Atsushi; Tsuruma, Kazuhiro; Hara, Hideaki

    2012-12-05

    Endoplasmic reticulum (ER) stress is implicated in various diseases. Recently, some reports have suggested that the sigma-1 receptor may play a role in ER stress, and many antidepressants have a high affinity for the sigma-1 receptor. In the present study, we focused on imipramine, a widely used antidepressant, and investigated whether it might protect against the neuronal cell death induced by tunicamycin, an ER stress inducer. In mouse cultured hippocampal HT22 cells, imipramine inhibited cell death and caspase-3 activation induced by tunicamycin, although it did not alter the elevated expressions of 78 kDa glucose-regulated protein (GRP78) and C/EBP-homologous protein (CHOP). Interestingly, in such cells application of imipramine normalized the expression of the sigma-1 receptor, which was decreased by treatment with tunicamycin alone. Additionally, NE-100, a selective sigma-1 receptor antagonist, abolished the protective effect of imipramine against such tunicamycin-induced cell death. Imipramine inhibited the reduction of mitochondrial membrane potential induced by tunicamycin, and NE-100 blocked this modulating effect of imipramine. Furthermore, in anesthetized mice intracerebroventricular administration of tunicamycin decreased the number of neuronal cells in the hippocampus, particularly in the CA1 and dentate gyrus (DG) areas, and 7 days' imipramine treatment (10mg/kg/day; i.p.) significantly suppressed these reductions in CA1 and DG. These findings suggest that imipramine protects against ER stress-induced hippocampal neuronal cell death both in vitro and in vivo. Such protection may be partly due to the sigma-1 receptor.

  1. Induced pluripotent stem cells for regenerative medicine.

    Science.gov (United States)

    Hirschi, Karen K; Li, Song; Roy, Krishnendu

    2014-07-11

    With the discovery of induced pluripotent stem (iPS) cells, it is now possible to convert differentiated somatic cells into multipotent stem cells that have the capacity to generate all cell types of adult tissues. Thus, there is a wide variety of applications for this technology, including regenerative medicine, in vitro disease modeling, and drug screening/discovery. Although biological and biochemical techniques have been well established for cell reprogramming, bioengineering technologies offer novel tools for the reprogramming, expansion, isolation, and differentiation of iPS cells. In this article, we review these bioengineering approaches for the derivation and manipulation of iPS cells and focus on their relevance to regenerative medicine.

  2. TALEN-Induced Translocations in Human Cells.

    Science.gov (United States)

    Piganeau, Marion; Renouf, Benjamin; Ghezraoui, Hind; Brunet, Erika

    2016-01-01

    Induction of chromosomal translocations in human cells is of a great interest to study tumorigenesis and genome instability. Here, we explain in detail a method to induce translocations using the transcription activator-like effector nucleases (TALENs). We describe how to detect translocation formation by PCR, calculate translocation frequency by 96-well PCR screen, and analyze breakpoint junctions. When inducing cancer translocations, it is also possible to detect the fusion gene by FISH analysis or western blot.

  3. Optically-Induced Cell Fusion on Cell Pairing Microstructures

    Science.gov (United States)

    Yang, Po-Fu; Wang, Chih-Hung; Lee, Gwo-Bin

    2016-02-01

    Cell fusion is a critical operation for numerous biomedical applications including cell reprogramming, hybridoma formation, cancer immunotherapy, and tissue regeneration. However, unstable cell contact and random cell pairings have limited efficiency and yields when utilizing traditional methods. Furthermore, it is challenging to selectively perform cell fusion within a group of cells. This study reports a new approach called optically-induced cell fusion (OICF), which integrates cell-pairing microstructures with an optically-induced, localized electrical field. By projecting light patterns onto a photoconductive film (hydrogen-rich, amorphous silicon) coated on an indium-tin-oxide (ITO) glass while an alternating current electrical field was applied between two such ITO glass slides, “virtual” electrodes could be generated that could selectively fuse pairing cells. At 10 kHz, a 57% cell paring rate and an 87% fusion efficiency were successfully achieved at a driving voltage of 20  Vpp, suggesting that this new technology could be promising for selective cell fusion within a group of cells.

  4. Induced pluripotent stem cells and neurodegenerative diseases.

    Science.gov (United States)

    Chen, Chao; Xiao, Shi-Fu

    2011-04-01

    Neurodegenerative diseases, including Parkinson's disease, Alzheimer's disease and Amyotrophic Lateral Sclerosis, are characterized by idiopathic neuron loss in different regions of the central nervous system, which contributes to the relevant dysfunctions in the patients. The application of cell replacement therapy using human embryonic stem (hES) cells, though having attracted much attention, has been hampered by the intrinsic ethical problems. It has been demonstrated that adult somatic cells can be reprogrammed into the embryonic state, called induced pluripotent stem (iPS) cells. It is soon realized that iPS cells may be an alternative source for cell replacement therapy, because it raises no ethical problems and using patient-specific iPS cells for autologous transplantation will not lead to immunological rejection. What's more, certain types of neurons derived from patient-specific iPS cells may display disease-relevant phenotypes. Thus, patient-specific iPS cells can provide a unique opportunity to directly investigate the pathological properties of relevant neural cells in individual patient, and to study the vulnerability of neural cells to pathogenic factors in vitro, which may help reveal the pathogenesis of many neurodegenerative diseases. In this review, the recent development in cellular treatment of neurodegenerative diseases using iPS cells was summarized, and the potential value of iPS cells in the modeling of neurodegenerative disease was discussed.

  5. Sodium Valproate Induces Cell Senescence in Human Hepatocarcinoma Cells

    Directory of Open Access Journals (Sweden)

    Hong-Mei An

    2013-12-01

    Full Text Available Hepatocarcinogenesis is associated with epigenetic changes, including histone deacetylases (HDACs. Epigenetic modulation by HDAC inhibition is a potentially valuable approach for hepatocellular carcinoma treatment. In present study, we evaluated the anticancer effects of sodium valproate (SVP, a known HDAC inhibitor, in human hepatocarcinoma cells. The results showed SVP inhibited the proliferation of Bel-7402 cells in a dose-dependent manner. Low dose SVP treatment caused a large and flat morphology change, positive SA-β-gal staining, and G0/G1 phase cell cycle arrest in human hepatocarcinoma cells. Low dose SVP treatment also increased acetylation of histone H3 and H4 on p21 promoter, accompanied by up-regulation of p21 and down-regulation of RB phosphorylation. These observations suggested that a low dose of SVP could induce cell senescence in hepatocarcinoma cells, which might correlate with hyperacetylation of histone H3 and H4, up-regulation of p21, and inhibition of RB phosphorylation. Since the effective concentration inducing cell senescence in hepatocarcinoma cells is clinically available, whether a clinical dose of SVP could induce cell senescence in clinical hepatocarcinoma is worthy of further study.

  6. Failure of cell cleavage induces senescence in tetraploid primary cells.

    Science.gov (United States)

    Panopoulos, Andreas; Pacios-Bras, Cristina; Choi, Justin; Yenjerla, Mythili; Sussman, Mark A; Fotedar, Rati; Margolis, Robert L

    2014-10-15

    Tetraploidy can arise from various mitotic or cleavage defects in mammalian cells, and inheritance of multiple centrosomes induces aneuploidy when tetraploid cells continue to cycle. Arrest of the tetraploid cell cycle is therefore potentially a critical cellular control. We report here that primary rat embryo fibroblasts (REF52) and human foreskin fibroblasts become senescent in tetraploid G1 after drug- or small interfering RNA (siRNA)-induced failure of cell cleavage. In contrast, T-antigen-transformed REF52 and p53+/+ HCT116 tumor cells rapidly become aneuploid by continuing to cycle after cleavage failure. Tetraploid primary cells quickly become quiescent, as determined by loss of the Ki-67 proliferation marker and of the fluorescent ubiquitination-based cell cycle indicator/late cell cycle marker geminin. Arrest is not due to DNA damage, as the γ-H2AX DNA damage marker remains at control levels after tetraploidy induction. Arrested tetraploid cells finally become senescent, as determined by SA-β-galactosidase activity. Tetraploid arrest is dependent on p16INK4a expression, as siRNA suppression of p16INK4a bypasses tetraploid arrest, permitting primary cells to become aneuploid. We conclude that tetraploid primary cells can become senescent without DNA damage and that induction of senescence is critical to tetraploidy arrest.

  7. Nitrogen-induced surface area and conductivity modulation of carbon nanohorn and its function as an efficient metal-free oxygen reduction electrocatalyst for anion-exchange membrane fuel cells.

    Science.gov (United States)

    Unni, Sreekuttan M; Bhange, Siddheshwar N; Illathvalappil, Rajith; Mutneja, Nisha; Patil, Kasinath R; Kurungot, Sreekumar

    2015-01-21

    Nitrogen-doped carbon morphologies have been proven to be better alternatives to Pt in polymer-electrolyte membrane (PEM) fuel cells. However, efficient modulation of the active sites by the simultaneous escalation of the porosity and nitrogen doping, without affecting the intrinsic electrical conductivity, still remains to be solved. Here, a simple strategy is reported to solve this issue by treating single-walled carbon nanohorn (SWCNH) with urea at 800 °C. The resulting nitrogen-doped carbon nanohorn shows a high surface area of 1836 m2 g(-1) along with an increased electron conductivity, which are the pre-requisites of an electrocatalyst. The nitrogen-doped nanohorn annealed at 800 °C (N-800) also shows a high oxygen reduction activity (ORR). Because of the high weight percentage of pyridinic nitrogen coordination in N-800, the present catalyst shows a clear 4-electron reduction pathway at only 50 mV overpotential and 16 mV negative shift in the half-wave potential for ORR compared to Pt/C along with a high fuel selectivity and electrochemical stability. More importantly, a membrane electrode assembly (MEA) based on N-800 provides a maximum power density of 30 mW cm(-2) under anion-exchange membrane fuel cell (AEMFC) testing conditions. Thus, with its remarkable set of physical and electrochemical properties, this material has the potential to perform as an efficient Pt-free electrode for AEMFCs.

  8. Cell Death Mechanisms Induced by Cytotoxic Lymphocytes

    Institute of Scientific and Technical Information of China (English)

    Ch(a)vez-Gal(a)n L; Arenas-Del Angel MC; Zenteno E; Ch(a)vez 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 lyric molecules from effector cytotoxic cells and target-cell membrane to induction of apoptosis.

  9. Universal area distributions in the monolayers of confluent mammalian cells

    Science.gov (United States)

    Wilk, Gary; Iwasa, Masatomo; Fuller, Patrick E.; Kandere-Grzybowska, Kristiana; Grzybowski, Bartosz A.

    2014-01-01

    When mammalian cells form confluent monolayers completely filling a plane, these apparently random “tilings” show regularity in the statistics of cell areas for various types of epithelial and endothelial cells. The observed distributions are reproduced by a model which accounts for cell growth and division, with the latter treated stochastically both in terms of the sizes of the dividing cells as well as the sizes of the “newborn” ones – remarkably, the modeled and experimental distributions fit well when all free parameters are estimated directly from experiments. PMID:24745461

  10. Induced Pluripotent Stem Cells in Cardiovascular Medicine

    Directory of Open Access Journals (Sweden)

    Toru Egashira

    2011-01-01

    Full Text Available Induced pluripotent stem (iPS cells are generated by reprogramming human somatic cells through the forced expression of several embryonic stem (ES cell-specific transcription factors. The potential of iPS cells is having a significant impact on regenerative medicine, with the promise of infinite self-renewal, differentiation into multiple cell types, and no problems concerning ethics or immunological rejection. Human iPS cells are currently generated by transgene introduction principally through viral vectors, which integrate into host genomes, although the associated risk of tumorigenesis is driving research into nonintegration methods. Techniques for pluripotent stem cell differentiation and purification to yield cardiomyocytes are also advancing constantly. Although there remain some unsolved problems, cardiomyocyte transplantation may be a reality in the future. After those problems will be solved, applications of human iPS cells in human cardiovascular regenerative medicine will be envisaged for the future. Furthermore, iPS cell technology has generated new human disease models using disease-specific cells. This paper summarizes the progress of iPS cell technology in cardiovascular research.

  11. Trophoblast lineage cells derived from human induced pluripotent stem cells

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Ying, E-mail: ying.chen@hc.msu.edu [Department of Obstetrics, Gynecology and Reproductive Biology, Michigan State University, 333 Bostwick NE, Grand Rapids, MI 49503 (United States); Wang, Kai; Chandramouli, Gadisetti V.R. [Department of Obstetrics, Gynecology and Reproductive Biology, Michigan State University, 333 Bostwick NE, Grand Rapids, MI 49503 (United States); Knott, Jason G. [Developmental Epigenetics Laboratory, Department of Animal Science, Michigan State University (United States); Leach, Richard, E-mail: Richard.leach@hc.msu.edu [Department of Obstetrics, Gynecology and Reproductive Biology, Michigan State University, 333 Bostwick NE, Grand Rapids, MI 49503 (United States); Department of Obstetrics, Gynecology and Women’s Health, Spectrum Health Medical Group (United States)

    2013-07-12

    Highlights: •Epithelial-like phenotype of trophoblast lineage cells derived from human iPS cells. •Trophoblast lineage cells derived from human iPS cells exhibit trophoblast function. •Trophoblasts from iPS cells provides a proof-of-concept in regenerative medicine. -- Abstract: Background: During implantation, the blastocyst trophectoderm attaches to the endometrial epithelium and continues to differentiate into all trophoblast subtypes, which are the major components of a placenta. Aberrant trophoblast proliferation and differentiation are associated with placental diseases. However, due to ethical and practical issues, there is almost no available cell or tissue source to study the molecular mechanism of human trophoblast differentiation, which further becomes a barrier to the study of the pathogenesis of trophoblast-associated diseases of pregnancy. In this study, our goal was to generate a proof-of-concept model for deriving trophoblast lineage cells from induced pluripotency stem (iPS) cells from human fibroblasts. In future studies the generation of trophoblast lineage cells from iPS cells established from patient’s placenta will be extremely useful for studying the pathogenesis of individual trophoblast-associated diseases and for drug testing. Methods and results: Combining iPS cell technology with BMP4 induction, we derived trophoblast lineage cells from human iPS cells. The gene expression profile of these trophoblast lineage cells was distinct from fibroblasts and iPS cells. These cells expressed markers of human trophoblasts. Furthermore, when these cells were differentiated they exhibited invasive capacity and placental hormone secretive capacity, suggesting extravillous trophoblasts and syncytiotrophoblasts. Conclusion: Trophoblast lineage cells can be successfully derived from human iPS cells, which provide a proof-of-concept tool to recapitulate pathogenesis of patient placental trophoblasts in vitro.

  12. Heat induces gene amplification in cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Bin, E-mail: yanbin@mercyhealth.com [Department of Radiation Oncology, University of Mississippi Medical Center, Jackson, MS 39213 (United States); Mercy Cancer Center, Mercy Medical Center-North Iowa, Mason City, IA 50401 (United States); Ouyang, Ruoyun [Department of Respiratory Medicine, The Second Xiangya Hospital, Xinagya School of Medicine, Central South University, Changsha 410011 (China); Huang, Chenghui [Department of Radiation Oncology, University of Mississippi Medical Center, Jackson, MS 39213 (United States); Department of Oncology, The Third Xiangya Hospital, Xinagya School of Medicine, Central South University, Changsha 410013 (China); Liu, Franklin [Department of Radiation Oncology, Duke University Medical Center, Durham, NC 27710 (United States); Neill, Daniel [Department of Radiation Oncology, University of Mississippi Medical Center, Jackson, MS 39213 (United States); Li, Chuanyuan [Dermatology, Duke University Medical Center, Durham, NC 27710 (United States); Dewhirst, Mark [Department of Radiation Oncology, Duke University Medical Center, Durham, NC 27710 (United States)

    2012-10-26

    Highlights: Black-Right-Pointing-Pointer This study discovered that heat exposure (hyperthermia) results in gene amplification in cancer cells. Black-Right-Pointing-Pointer Hyperthermia induces DNA double strand breaks. Black-Right-Pointing-Pointer DNA double strand breaks are considered to be required for the initiation of gene amplification. Black-Right-Pointing-Pointer The underlying mechanism of heat-induced gene amplification is generation of DNA double strand breaks. -- Abstract: Background: Hyperthermia plays an important role in cancer therapy. However, as with radiation, it can cause DNA damage and therefore genetic instability. We studied whether hyperthermia can induce gene amplification in cancer cells and explored potential underlying molecular mechanisms. Materials and methods: (1) Hyperthermia: HCT116 colon cancer cells received water-submerged heating treatment at 42 or 44 Degree-Sign C for 30 min; (2) gene amplification assay using N-(phosphoacetyl)-L-aspartate (PALA) selection of cabamyl-P-synthetase, aspartate transcarbarmylase, dihydro-orotase (cad) gene amplified cells; (3) southern blotting for confirmation of increased cad gene copies in PALA-resistant cells; (4) {gamma}H2AX immunostaining to detect {gamma}H2AX foci as an indication for DNA double strand breaks. Results: (1) Heat exposure at 42 or 44 Degree-Sign C for 30 min induces gene amplification. The frequency of cad gene amplification increased by 2.8 and 6.5 folds respectively; (2) heat exposure at both 42 and 44 Degree-Sign C for 30 min induces DNA double strand breaks in HCT116 cells as shown by {gamma}H2AX immunostaining. Conclusion: This study shows that heat exposure can induce gene amplification in cancer cells, likely through the generation of DNA double strand breaks, which are believed to be required for the initiation of gene amplification. This process may be promoted by heat when cellular proteins that are responsible for checkpoints, DNA replication, DNA repair and

  13. Apoptosis of Cancer Cells Induced by HAP Nanoparticles

    Institute of Scientific and Technical Information of China (English)

    HU Sheng; LI Shipu; YAN Yuhua; WANG Youfa; CAO Xianying

    2005-01-01

    To confirm apoptosis is one of the hepatoma cells death pathways after HAP nanoparticles absorption, hepatoma cells were collected for ultrathin sections preparation and examined under a transmission electron microscope (TEM) after 1 h incubation with HAP nanoparticle. Apoptosis was detected by TUNEL technique. After absorption, some vacuoles with membrane containing HAP nanoparticles were found in cytoplasma.The nuclear envelope shrinked, and some area pullulated from nucleus. The karyotin became pycnosis and assembled at the edge. An apoptosis body was found. And the data of IOD and numbers of the positive apoptosic signals in nuclear area of slides could illustrate much more apoptosis in the HAP group than those in the control group ( P < 0.001 ). The experimental results indicate that the HAP nanoparticles can induce cancer cells apoptosis.

  14. Ionizing radiation induces stemness in cancer cells.

    Directory of Open Access Journals (Sweden)

    Laura Ghisolfi

    Full Text Available The cancer stem cell (CSC model posits the presence of a small number of CSCs in the heterogeneous cancer cell population that are ultimately responsible for tumor initiation, as well as cancer recurrence and metastasis. CSCs have been isolated from a variety of human cancers and are able to generate a hierarchical and heterogeneous cancer cell population. CSCs are also resistant to conventional chemo- and radio-therapies. Here we report that ionizing radiation can induce stem cell-like properties in heterogeneous cancer cells. Exposure of non-stem cancer cells to ionizing radiation enhanced spherogenesis, and this was accompanied by upregulation of the pluripotency genes Sox2 and Oct3/4. Knockdown of Sox2 or Oct3/4 inhibited radiation-induced spherogenesis and increased cellular sensitivity to radiation. These data demonstrate that ionizing radiation can activate stemness pathways in heterogeneous cancer cells, resulting in the enrichment of a CSC subpopulation with higher resistance to radiotherapy.

  15. Resveratrol induces apoptosis in pancreatic cancer cells

    Institute of Scientific and Technical Information of China (English)

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

    2011-01-01

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

  16. Immunohistochemical study of hair follicle stem cells in regenerated hair follicles induced by Wnt10b

    Science.gov (United States)

    Zhang, Yiming; Xing, Yizhan; Guo, Haiying; Ma, Xiaogen; Li, Yuhong

    2016-01-01

    The regulation of the periodic regeneration of hair follicles is complicated. Although Wnt10b has been reported to induce hair follicle regeneration, the characteristics of induced hair follicles, especially the target cells of Wnt10b, have not yet been clearly elucidated. Thus, we systematically evaluated the expression and proliferation patterns of Wnt10b-induced hair follicles. We found that Wnt10b promoted the proliferation of hair follicle stem cells from 24 hours after AdWnt10b injection. Seventy-two hours after AdWnt10b injection, cells outside of bulge area began to proliferate. When the induced hair follicle entered full anagen, although the hair follicle stem cells were normal, canonical Wnt signaling was maintained in the hair precortex cells. Our results reveal that the target cells that overexpressed Wnt10b included hair follicle stem cells, hair precortex cells, and matrix cells.

  17. Induced pluripotent stem cells for cardiac repair.

    Science.gov (United States)

    Zwi-Dantsis, Limor; Gepstein, Lior

    2012-10-01

    Myocardial stem cell therapies are emerging as novel therapeutic paradigms for myocardial repair, but are hampered by the lack of sources for autologous human cardiomyocytes. An exciting development in the field of cardiovascular regenerative medicine is the ability to reprogram adult somatic cells into pluripotent stem cell lines (induced pluripotent stem cells, iPSCs) and to coax their differentiation into functional cardiomyocytes. This technology holds great promise for the emerging disciplines of personalized and regenerative medicine, because of the ability to derive patient-specific iPSCs that could potentially elude the immune system. The current review describes the latest techniques of generating iPSCs as well as the methods used to direct their differentiation towards the cardiac lineage. We then detail the unique potential as well as the possible hurdles on the road to clinical utilizing of the iPSCs derived cardiomyocytes in the emerging field of cardiovascular regenerative medicine.

  18. Chemical chaperones reduce ionizing radiation-induced endoplasmic reticulum stress and cell death in IEC-6 cells

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Eun Sang; Lee, Hae-June; Lee, Yoon-Jin [Division of Radiation Effects, Korea Institute of Radiological and Medical Sciences, Seoul 139-706 (Korea, Republic of); Jeong, Jae-Hoon [Division of Radiotherapy, Korea Institute of Radiological and Medical Sciences, Seoul 139-706 (Korea, Republic of); Kang, Seongman [Division of Life Sciences, Korea University, Seoul 136-701 (Korea, Republic of); Lim, Young-Bin, E-mail: yblim@kirams.re.kr [Division of Radiation Effects, Korea Institute of Radiological and Medical Sciences, Seoul 139-706 (Korea, Republic of)

    2014-07-25

    Highlights: • UPR activation precedes caspase activation in irradiated IEC-6 cells. • Chemical ER stress inducers radiosensitize IEC-6 cells. • siRNAs that targeted ER stress responses ameliorate IR-induced cell death. • Chemical chaperons prevent cell death in irradiated IEC-6 cells. - Abstract: Radiotherapy, which is one of the most effective approaches to the treatment of various cancers, plays an important role in malignant cell eradication in the pelvic area and abdomen. However, it also generates some degree of intestinal injury. Apoptosis in the intestinal epithelium is the primary pathological factor that initiates radiation-induced intestinal injury, but the mechanism by which ionizing radiation (IR) induces apoptosis in the intestinal epithelium is not clearly understood. Recently, IR has been shown to induce endoplasmic reticulum (ER) stress, thereby activating the unfolded protein response (UPR) signaling pathway in intestinal epithelial cells. However, the consequences of the IR-induced activation of the UPR signaling pathway on radiosensitivity in intestinal epithelial cells remain to be determined. In this study, we investigated the role of ER stress responses in IR-induced intestinal epithelial cell death. We show that chemical ER stress inducers, such as tunicamycin or thapsigargin, enhanced IR-induced caspase 3 activation and DNA fragmentation in intestinal epithelial cells. Knockdown of Xbp1 or Atf6 with small interfering RNA inhibited IR-induced caspase 3 activation. Treatment with chemical chaperones prevented ER stress and subsequent apoptosis in IR-exposed intestinal epithelial cells. Our results suggest a pro-apoptotic role of ER stress in IR-exposed intestinal epithelial cells. Furthermore, inhibiting ER stress may be an effective strategy to prevent IR-induced intestinal injury.

  19. UV-Induced Cell Death in Plants

    Directory of Open Access Journals (Sweden)

    Chang Ho Kang

    2013-01-01

    Full Text Available Plants are photosynthetic organisms that depend on sunlight for energy. Plants respond to light through different photoreceptors and show photomorphogenic development. Apart from Photosynthetically Active Radiation (PAR; 400–700 nm, plants are exposed to UV light, which is comprised of UV-C (below 280 nm, UV-B (280–320 nm and UV-A (320–390 nm. The atmospheric ozone layer protects UV-C radiation from reaching earth while the UVR8 protein acts as a receptor for UV-B radiation. Low levels of UV-B exposure initiate signaling through UVR8 and induce secondary metabolite genes involved in protection against UV while higher dosages are very detrimental to plants. It has also been reported that genes involved in MAPK cascade help the plant in providing tolerance against UV radiation. The important targets of UV radiation in plant cells are DNA, lipids and proteins and also vital processes such as photosynthesis. Recent studies showed that, in response to UV radiation, mitochondria and chloroplasts produce a reactive oxygen species (ROS. Arabidopsis metacaspase-8 (AtMC8 is induced in response to oxidative stress caused by ROS, which acts downstream of the radical induced cell death (AtRCD1 gene making plants vulnerable to cell death. The studies on salicylic and jasmonic acid signaling mutants revealed that SA and JA regulate the ROS level and antagonize ROS mediated cell death. Recently, molecular studies have revealed genes involved in response to UV exposure, with respect to programmed cell death (PCD.

  20. Effect of Stem Cell Therapy on Adriamycin Induced Tubulointerstitial Injury

    Science.gov (United States)

    Zickri, Maha Baligh; Zaghloul, Somaya; Farouk, Mira; Fattah, Marwa Mohamed Abdel

    2012-01-01

    Background and Objectives It was postulated that adriamycin (ADR) induce renal tubulointerstitial injury. Clinicians are faced with a challenge in producing response in renal patients and slowing or halting the evolution towards kidney failure. The present study aimed at investigating the relation between the possible therapeutic effect of human mesenchymal stem cells (HMSCs), isolated from cord blood on tubular renal damage and their distribution by using ADR induced nephrotoxicity as a model in albino rat. Methods and Results Thirty three male albino rats were divided into control group, ADR group where rats were given single intraperitoneal (IP) injection of 5 mg/kg adriamycin. The rats were sacrificed 10, 20 and 30 days following confirmation of tubular injury. In stem cell therapy group, rats were injected with HMSCs following confirmation of renal injury and sacrificed 10, 20 and 30 days after HMSCs therapy. Kidney sections were exposed to histological, histochemical, immunohistochemical, morphometric and serological studies. In response to SC therapy, vacuolated cytoplasm, dark nuclei, detached epithelial lining and desquamated nuclei were noticed in few collecting tubules (CT). 10, 20 and 30 days following therapy. The mean count of CT showing desquamated nuclei and mean value of serum creatinine revealed significant difference in ADR group. The mean area% of Prussian blue+ve cells and that of CD105 +ve cells measured in subgroup S1 denoted a significant increase compared to subgroups S2 and S3. Conclusions ADR induced tubulointerstitial damage that regressed in response to cord blood HMSC therapy. PMID:24298366

  1. The future of induced pluripotent stem cells for cardiac therapy and drug development.

    Science.gov (United States)

    Thorrez, Lieven; Sampaolesi, Maurilio

    2011-10-01

    The field of stem cell research was revolutionized with the advent of induced pluripotent stem cells. By reprogramming somatic cells to pluripotent stem cells, most ethical concerns associated with the use of embryonic stem cells are overcome, such that many hopes from the stem cell field now seem a step closer to reality. Several methods and cell sources have been described to create induced pluripotent stem cells and we discuss their characteristics in terms of feasibility and efficiency. From these cells, cardiac progenitors and cardiomyocytes can be derived by several protocols and most recent advances as well as remaining limitations are being discussed. However, in the short time period this technology has been around, evidence emerges that induced pluripotent stem cells may be more prone to genetic defects and maintain an epigenetic memory and thus may not be entirely the same as embryonic stem cells. Despite the lack of a complete fundamental understanding of stem cell biology, and even more of ways how to coax them into defined cell types, the technology is quickly adopted by industry. This paper gives an overview of the current applications of induced pluripotent stem cells in cardiovascular drug development and highlights active areas of research towards functional repair of the damaged heart. Adult stem cells have already been taken to clinical trials and we discuss these results in light of potential and hurdles to be taken to move induced pluripotent stem cells to the clinic.

  2. Effects of cell area on the performance of dye sensitized solar cell

    Energy Technology Data Exchange (ETDEWEB)

    Khatani, Mehboob, E-mail: mkhatani@hotmail.com, E-mail: noranimuti-mohamed@petronas.com.my, E-mail: hishmid@petronas.com.my, E-mail: azclement@yahoo.com, E-mail: aeska07@gmail.com; Mohamed, Norani Muti, E-mail: mkhatani@hotmail.com, E-mail: noranimuti-mohamed@petronas.com.my, E-mail: hishmid@petronas.com.my, E-mail: azclement@yahoo.com, E-mail: aeska07@gmail.com; Hamid, Nor Hisham, E-mail: mkhatani@hotmail.com, E-mail: noranimuti-mohamed@petronas.com.my, E-mail: hishmid@petronas.com.my, E-mail: azclement@yahoo.com, E-mail: aeska07@gmail.com; Sahmer, Ahmad Zahrin, E-mail: mkhatani@hotmail.com, E-mail: noranimuti-mohamed@petronas.com.my, E-mail: hishmid@petronas.com.my, E-mail: azclement@yahoo.com, E-mail: aeska07@gmail.com; Samsudin, Adel, E-mail: mkhatani@hotmail.com, E-mail: noranimuti-mohamed@petronas.com.my, E-mail: hishmid@petronas.com.my, E-mail: azclement@yahoo.com, E-mail: aeska07@gmail.com [Centre of Innovative Nanostructures and Nanodevices (COINN), UTP (Malaysia)

    2014-10-24

    Dye sensitized solar cells (DSCs) have significant advantage over the current silicon cells by having low manufacturing cost and potentially high conversion efficiency. Therefore, DSCs are expected to be used as the next generation solar cell device that covers wide range of new applications. In order to achieve highly efficient DSCs for practical application, study on the effect of increasing the cell’s area on the performance of dye sensitized solar need to be carried out. Three different DSC cell areas namely, 1, 12.96 and 93.5 cm{sup 2} respectively were fabricated and analyzed through solar simulator and electrochemical impedance spectroscopy (EIS). From the analysis of electrochemical impedance spectroscopy (EIS), it was observed that the cell’s electron lifetime was influenced significantly by the cell’s area. Although the collection efficiency of all cells recorded to be approximately 100% but higher recombination rate with increased cell area reduced the performance of the cell.

  3. Chemical -induced apoptotic cell death in tomato cells : involvement of caspase-like proteases

    NARCIS (Netherlands)

    Jong, de A.J.; Hoeberichts, F.A.; Yakimova, E.T.; Maximova, E.; Woltering, E.J.

    2000-01-01

    A new system to study programmed cell death in plants is described. Tomato (Lycopersicon esculentum Mill.) suspension cells were induced to undergo programmed cell death by treatment with known inducers of apoptosis in mammalian cells. This chemical-induced cell death was accompanied by the characte

  4. Uranium induces apoptosis in lung epithelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Periyakaruppan, Adaikkappan; Sarkar, Shubhashish; Sadanandan, Bindu; Thomas, Renard; Wilson, Bobby L. [Texas Southern University, Environmental Toxicology Program, Department of Chemistry, Houston, TX (United States); Ravichandran, Prabakaran; Sharma, Chidananda S.; Ramesh, Vani; Hall, Joseph C.; Ramesh, Govindarajan T. [Norfolk State University, Molecular Toxicology Laboratory, Department of Biology, Center for Biotechnology and Biomedical Sciences, Norfolk, VA (United States)

    2009-06-15

    Uranium is a naturally occurring radioactive material present everywhere in the environment. It is toxic because of its chemical or radioactive properties. Uranium enters environment mainly from mines and industry and cause threat to human health by accumulating in lungs as a result of inhalation. In our previous study, we have shown the effectiveness of antioxidant system response to the oxidative stress induced by uranyl acetate (UA) in rat lung epithelial (LE) cells. As part of our continuing studies; here, we investigated the mechanism underlying when LE cells are exposed to different concentration of UA. Oxidative stress may lead to apoptotic signaling pathways. LE cells treated with 0.25, 0.5 and 1 mM of UA results in dose and time-dependent increase in activity of both caspases-3 and -8. Increase in the concentration of cytochrome-c oxidase in cytosol was seen in LE cells treated with 1 mM UA as a result of mitochondria membrane permeability. The cytochrome-c leakage may trigger the apoptotic pathway. TUNEL assay performed in LE cells treated with 1 mM of UA showed significant incorporation of dNTPs in the nucleus after 24 h. In the presence of the caspase inhibitors, we observed the significant decrease in the activity of caspases-8 and -3 in 0.5 and 1 mM UA-treated LE cells. (orig.)

  5. Differentiation of human embryonic stem cells and induced pluripotent stem cells to cardiomyocytes: a methods overview.

    Science.gov (United States)

    Mummery, Christine L; Zhang, Jianhua; Ng, Elizabeth S; Elliott, David A; Elefanty, Andrew G; Kamp, Timothy J

    2012-07-20

    Since human embryonic stem cells were first differentiated to beating cardiomyocytes a decade ago, interest in their potential applications has increased exponentially. This has been further enhanced over recent years by the discovery of methods to induce pluripotency in somatic cells, including those derived from patients with hereditary cardiac diseases. Human pluripotent stem cells have been among the most challenging cell types to grow stably in culture, but advances in reagent development now mean that most laboratories can expand both embryonic and induced pluripotent stem cells robustly using commercially available products. However, differentiation protocols have lagged behind and in many cases only produce the cell types required with low efficiency. Cardiomyocyte differentiation techniques were also initially inefficient and not readily transferable across cell lines, but there are now a number of more robust protocols available. Here, we review the basic biology underlying the differentiation of pluripotent cells to cardiac lineages and describe current state-of-the-art protocols, as well as ongoing refinements. This should provide a useful entry for laboratories new to this area to start their research. Ultimately, efficient and reliable differentiation methodologies are essential to generate desired cardiac lineages to realize the full promise of human pluripotent stem cells for biomedical research, drug development, and clinical applications.

  6. Activation-Induced Cell Death in T Cells and Autoimmunity

    Institute of Scientific and Technical Information of China (English)

    Jian Zhang; Xuemei Xu; Yong Liu

    2004-01-01

    Activation-induced cell death (AICD), which results from the interaction between Fas and Fas ligand, is responsible for maintaining tolerance to self-antigen. A defect in AICD may lead to development of autoimmunity. During the last several years, much progress has been made in understanding the mechanism(s) of AICD and its potential role in the pathogenesis of autoimmune diseases. In this review, we summarize the most recent progress on the regulation of the susceptibility of T cells to AICD and its possible involvement in autoimmune diseases.

  7. Cell signalling pathways underlying induced pluripotent stem cell reprogramming

    Institute of Scientific and Technical Information of China (English)

    Kate; Hawkins; Shona; Joy; Tristan; Mc; Kay

    2014-01-01

    Induced pluripotent stem(i PS) cells, somatic cells reprogrammed to the pluripotent state by forced expression of defined factors, represent a uniquely valuable resource for research and regenerative medicine. However, this methodology remains inefficient due to incomplete mechanistic understanding of the reprogramming process. In recent years, various groups have endeavoured to interrogate the cell signalling that governs the reprogramming process, including LIF/STAT3, BMP, PI3 K, FGF2, Wnt, TGFβ and MAPK pathways, with the aim of increasing our understanding and identifying new mechanisms of improving safety, reproducibility and efficiency. This has led to a unified model of reprogramming that consists of 3 stages: initiation, maturation and stabilisation. Initiation of reprogramming occurs in almost all cells that receive the reprogramming transgenes; most commonly Oct4, Sox2, Klf4 and c Myc, and involves a phenotypic mesenchymal-to-epithelial transition. The initiation stage is also characterised by increased proliferation and a metabolic switch from oxidative phosphorylation to glycolysis. The maturation stage is considered the major bottleneck within the process, resulting in very few "stabilisation competent" cells progressing to the final stabilisation phase. To reach this stage in both mouse and human cells, pre-i PS cells must activate endogenous expression of the core circuitry of pluripotency, comprising Oct4, Sox2, and Nanog, and thus reach a state of transgene independence. By the stabilisation stage, i PS cells generally use the same signalling networks that govern pluripotency in embryonic stem cells. These pathways differ between mouse and human cells although recent work has demonstrated that this is context dependent. As i PS cell generation technologies move forward, tools are being developed to interrogate the process in more detail, thus allowing a greater understanding of this intriguing biological phenomenon.

  8. Derivation of induced pluripotent stem cells from pig somatic cells.

    Science.gov (United States)

    Ezashi, Toshihiko; Telugu, Bhanu Prakash V L; Alexenko, Andrei P; Sachdev, Shrikesh; Sinha, Sunilima; Roberts, R Michael

    2009-07-07

    For reasons that are unclear the production of embryonic stem cells from ungulates has proved elusive. Here, we describe induced pluripotent stem cells (iPSC) derived from porcine fetal fibroblasts by lentiviral transduction of 4 human (h) genes, hOCT4, hSOX2, hKLF4, and hc-MYC, the combination commonly used to create iPSC in mouse and human. Cells were cultured on irradiated mouse embryonic fibroblasts (MEF) and in medium supplemented with knockout serum replacement and FGF2. Compact colonies of alkaline phosphatase-positive cells emerged after approximately 22 days, providing an overall reprogramming efficiency of approximately 0.1%. The cells expressed porcine OCT4, NANOG, and SOX2 and had high telomerase activity, but also continued to express the 4 human transgenes. Unlike human ESC, the porcine iPSC (piPSC) were positive for SSEA-1, but negative for SSEA-3 and -4. Transcriptional profiling on Affymetrix (porcine) microarrays and real time RT-PCR supported the conclusion that reprogramming to pluripotency was complete. One cell line, ID6, had a normal karyotype, a cell doubling time of approximately 17 h, and has been maintained through >220 doublings. The ID6 line formed embryoid bodies, expressing genes representing all 3 germ layers when cultured under differentiating conditions, and teratomas containing tissues of ectoderm, mesoderm, and endoderm origin in nude mice. We conclude that porcine somatic cells can be reprogrammed to form piPSC. Such cell lines derived from individual animals could provide a means for testing the safety and efficacy of stem cell-derived tissue grafts when returned to the same pigs at a later age.

  9. Tissue Regeneration and Stem Cell Distribution in Adriamycin Induced Glomerulopathy

    Science.gov (United States)

    Zickri, Maha Baligh; Fattah, Marwa Mohamed Abdel; Metwally, Hala Gabr

    2012-01-01

    Background and Objectives Glomerulosclerosis develops secondary to various kidney diseases. It was postulated that adriamycin (ADR) induce chronic glomerulopathy. Treatment combinations for one year did not significantly modify renal function in resistant focal segmental glomerulosclerosis (FSGS). Recurrence of FSGS after renal transplantation impacts long-term graft survival and limits access to transplantation. The present study aimed at investigating the relation between the possible therapeutic effect of human mesenchymal stem cells (HMSCs), isolated from cord blood on glomerular damage and their distribution by using ADR induced nephrotoxicity as a model in albino rat. Methods and Results Thirty three male albino rats were divided into control group, ADR group where rats were given single intraperitoneal (IP) injection of 5 mg/kg adriamycin. The rats were sacrificed 10, 20 and 30 days following confirmation of glomerular injury. In stem cell therapy group, rats were injected with HMSCs following confirmation of renal injury and sacrificed 10, 20 and 30 days after HMSCs therapy. Kidney sections were exposed to histological, histochemical, immunohistochemical, morphometric and serological studies. In response to SC therapy multiple Malpighian corpuscles (MC) appeared with patent Bowman's space (Bs) 10 and 20 days following therapy. One month following therapy no remarkable shrunken glomeruli were evident. Glomerular area and serum creatinine were significantly different in ADR group in comparison to control and SC therapy groups. Conclusions ADR induced glomerulosclerosis regressed in response to cord blood HMSC therapy. A reciprocal relation was recorded between the extent of renal regeneration and the distribution of undifferentiated mesenchymal stem cells. PMID:24298364

  10. Reprogramming T cell Lymphocytes to Induced Pluripotent Stem Cells

    Science.gov (United States)

    Bared, Kalia

    The discovery of induced pluripotent stem cells (iPSC) provided a novel technology for the study of development and pharmacology and complement embryonic stem cells (ES) for cell therapy applications. Though iPSC are derived from adult tissue they are comparable to ES cells in their behavior; multi-lineage differentiation and self-renewal. This makes iPSC research appealing because they can be studied in great detail and expanded in culture broadly. Fibroblasts were the first cell type reprogrammed to an iPSC using a retrovirus vector, since then alternative cell types including lymphocytes have been used to generate iPSC. Different types of vectors have also been developed to enhance iPSC formation and quality. However, specific T lymphocyte subsets have not been shown to reprogram to a pluripotent state to date. Here, we proposed to derive iPSC from peripheral blood effector and central memory T cells, reasoning that the resultant iPSC will maintain the epigenetic memory of a T lymphocyte, including the T cell receptor (TCR) gene rearrangement. This epigenetic memory will enable the differentiation and expansion of T cell iPSC into professional T cells containing a specific TCR. These could then be used for cell therapy to target specific antigens, as well as to improve culture techniques to expand T cells in vitro. We studied different gene delivery methods to derive iPSC from different types of T lymphocytes. We assessed the viability of viral transduction using flow cytometry to detect green fluorescent marker contained in the viral construct and quantitative real time polymerase chain reaction (qRT-PCR) to detect Oct4, Klf4, Sox2, and c-Myc gene expression. Our results demonstrate that the Sendai virus construct is the most feasible platform to reprogram T lymphocytes. We anticipate that this platform will provide an efficient and safe approach to derive iPSC from different T cell subsets, including memory T cells.

  11. Binase induces apoptosis of transformed myeloid cells and does not induce T-cell immune response.

    Science.gov (United States)

    Ilinskaya, Olga N; Zelenikhin, Pavel V; Petrushanko, Irina Yu; Mitkevich, Vladimir A; Prassolov, Vladimir S; Makarov, Alexander A

    2007-10-01

    Microbial RNases along with such animal RNases as onconase and BS-RNase are a promising basis for developing new antitumor drugs. We have shown that the Bacillus intermedius RNase (binase) induces selective apoptosis of transformed myeloid cells. It attacks artificially expressing activated c-Kit myeloid progenitor FDC cells and chronic myelogenous leukemia cells K562. Binase did not induce apoptosis in leukocytes of healthy donors and in normal myeloid progenitor cells. The inability of binase to initiate expression of activation markers CD69 and IFN-gamma in CD4+ and CD8+ T-lymphocytes testifies that enzyme is devoid of superantigenic properties. Altogether, these results demonstrate that binase possesses therapeutic opportunities for treatment of genotyped human neoplasms expressing activated kit.

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

    DEFF Research Database (Denmark)

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

    1998-01-01

    induced apoptosis in several activated T-cell populations and T-cell lines, including T-cell antigen receptor (TCR)-CD3-negative T-cell lines. In contrast, RPE cells induced little or no apoptosis in resting peripheral T cells. Major histocompatibility complex (MHC) class II monoclonal antibodies, which...

  13. Erythroid differentiation of human induced pluripotent stem cells is independent of donor cell type of origin

    OpenAIRE

    2015-01-01

    Epigenetic memory in induced pluripotent stem cells, which is related to the somatic cell type of origin of the stem cells, might lead to variations in the differentiation capacities of the pluripotent stem cells. In this context, induced pluripotent stem cells from human CD34+ hematopoietic stem cells might be more suitable for hematopoietic differentiation than the commonly used fibroblast-derived induced pluripotent stem cells. To investigate the influence of an epigenetic memory on the ex...

  14. Young at Heart: Pioneering Approaches to Model Nonischaemic Cardiomyopathy with Induced Pluripotent Stem Cells

    Science.gov (United States)

    Gowran, Aoife; Rasponi, Marco; Perrucci, Gianluca L.; Righetti, Stefano; Zanobini, Marco; Pompilio, Giulio

    2016-01-01

    A mere 9 years have passed since the revolutionary report describing the derivation of induced pluripotent stem cells from human fibroblasts and the first in-patient translational use of cells obtained from these stem cells has already been achieved. From the perspectives of clinicians and researchers alike, the promise of induced pluripotent stem cells is alluring if somewhat beguiling. It is now evident that this technology is nascent and many areas for refinement have been identified and need to be considered before induced pluripotent stem cells can be routinely used to stratify, treat and cure patients, and to faithfully model diseases for drug screening purposes. This review specifically addresses the pioneering approaches to improve induced pluripotent stem cell based models of nonischaemic cardiomyopathy. PMID:27110250

  15. Self-induced transparency mode-locking, and area theorem

    CERN Document Server

    Arkhipov, R M; Babushkin, I

    2015-01-01

    Self-induced transparency mode-locking (or coherent mode-locking, CML) which is based on intracavity self-induced transparency soliton dynamics, allows potentially to achieve nearly single cycle intracavity pulse durations, much below the phase relaxation time $T_2$ in a laser, which, despite of great promise, has not yet been realized experimentally. We develop a diagram technique which allows to predict the main features of CML regimes in a generic two-section laser. We show that CML can arise directly at the first laser threshold if the phase relaxation time is large enough. Furthermore, CML regimes can be unconditionally stable. We also predict the existence of ``super-CML regimes``, with a pulse coupled to several Rabi oscillations in the nonlinear medium.

  16. Predicting Ground Motion from Induced Earthquakes in Geothermal Areas

    Science.gov (United States)

    Douglas, J.; Edwards, B.; Convertito, V.; Sharma, N.; Tramelli, A.; Kraaijpoel, D.; Cabrera, B. M.; Maercklin, N.; Troise, C.

    2013-06-01

    Induced seismicity from anthropogenic sources can be a significant nuisance to a local population and in extreme cases lead to damage to vulnerable structures. One type of induced seismicity of particular recent concern, which, in some cases, can limit development of a potentially important clean energy source, is that associated with geothermal power production. A key requirement for the accurate assessment of seismic hazard (and risk) is a ground-motion prediction equation (GMPE) that predicts the level of earthquake shaking (in terms of, for example, peak ground acceleration) of an earthquake of a certain magnitude at a particular distance. Few such models currently exist in regard to geothermal-related seismicity, and consequently the evaluation of seismic hazard in the vicinity of geothermal power plants is associated with high uncertainty. Various ground-motion datasets of induced and natural seismicity (from Basel, Geysers, Hengill, Roswinkel, Soultz, and Voerendaal) were compiled and processed, and moment magnitudes for all events were recomputed homogeneously. These data are used to show that ground motions from induced and natural earthquakes cannot be statistically distinguished. Empirical GMPEs are derived from these data; and, although they have similar characteristics to recent GMPEs for natural and mining-related seismicity, the standard deviations are higher. To account for epistemic uncertainties, stochastic models subsequently are developed based on a single corner frequency and with parameters constrained by the available data. Predicted ground motions from these models are fitted with functional forms to obtain easy-to-use GMPEs. These are associated with standard deviations derived from the empirical data to characterize aleatory variability. As an example, we demonstrate the potential use of these models using data from Campi Flegrei.

  17. The Preliminary Experimental Study of Induced Differentiation of Embryonic Stem Cells into Corneal Epithelial Cells

    Institute of Scientific and Technical Information of China (English)

    Ling Yu; Jian Ge; Zhichong Wang; Bing Huang; Keming Yu; Chongde Long; Xigu Chen

    2001-01-01

    Purpose:To study preliminarily induced differentiation of embryonic stem cells intocorneal epithelial cells in vitro.Methods: Murine embryonic stem cells were co-cultured with Rabbit limbal cornealepithelial cells in Transwell system to induce differentiation. Mophological andimmunohistochemical examination were implemented.Results: The induced cells from embryonic stem cells have an epithelial appearance.The cells formed a network and were confluent into film gradually after beingco-cultured with rabbit limbal corneal epithelial cells for 24 ~ 96 hours. The cells rangedmosaic structure and localized together with clear rim. Most of the cells showedpolygonal appearance. Transmission electron microscope showed lots of microvilli on thesurface of induced cells and tight junctions between them. These epithelial-like cellsexpressed the corneal epithelial cell specific marker cytokeratin3/cytokeratinl2.Conclusion: The potential mechanism of the differentiation of murine embryonic stemcells into corneal epithelial cells induced by limbal corneal epithelial cell-derivedinducing activity is to be further verified.

  18. Vegetation succession process induced by reforestation in erosion areas

    Institute of Scientific and Technical Information of China (English)

    Feixin WANG; Zhaoyin WANG; Zhengming YANG; Xining JI

    2008-01-01

    Reforestation is one of the most important and efficient measures of water and soil conservation. Based on field investigations in the Shangyang Soil Conservation and Reforestation Station in Huizhou, Guangdong Province, China, we studied the variation in vegetation development, vegetation succession processes and soil erosion. The regional vegetation consists mainly of monsoon evergreen broad-leaved forests (MEBF). The area was deforested and became a denuded hill area with extremely high soil erosion in the 1960s and 1970s. Then, the area was closed in order to allow recovery of the vegetation. Under natural condi-tions the vegetation development and succession processes were slow during which soil erosion and strong sunshine and evaporation slowed down the development of the vegetation. About 25 years later, the vegetation cover was still merely 35% or so. The dominant vegetation types were heliophilous herbage and shrubs which formed a poorly developed shrub-herbage community and erosion remained high. In contrast, reforestation with selected tree species dramatically speeded up the vegetation succession process. About 12 years after reforestation, vegetation cover of the Acacia auriculiformis plantations in the Shangyang Station was 90% and erosion was under control. After 23 years, understory vegetation, consisting of indigenous species, had developed in the plantations. The planted trees and naturally developing herbage, shrubs, bamboo, local trees and liana formed a complex vegetation community in three layers. It will take 60 years for the vegetation to succeed from bare land to a secondary growth forest under natural conditions. Reforestation may speed up the vegetation suc-cession process. The time may be reduced to 20 years. Reforestation is the most effective measure of vegetation restoration and erosion control in this area.

  19. Berberine induces caspase-independent cell death in colon tumor cells through activation of apoptosis-inducing factor.

    Directory of Open Access Journals (Sweden)

    Lihong Wang

    Full Text Available Berberine, an isoquinoline alkaloid derived from plants, is a traditional medicine for treating bacterial diarrhea and intestinal parasite infections. Although berberine has recently been shown to suppress growth of several tumor cell lines, information regarding the effect of berberine on colon tumor growth is limited. Here, we investigated the mechanisms underlying the effects of berberine on regulating the fate of colon tumor cells, specifically the mouse immorto-Min colonic epithelial (IMCE cells carrying the Apc(min mutation, and of normal colon epithelial cells, namely young adult mouse colonic epithelium (YAMC cells. Berberine decreased colon tumor colony formation in agar, and induced cell death and LDH release in a time- and concentration-dependent manner in IMCE cells. In contrast, YAMC cells were not sensitive to berberine-induced cell death. Berberine did not stimulate caspase activation, and PARP cleavage and berberine-induced cell death were not affected by a caspase inhibitor in IMCE cells. Rather, berberine stimulated a caspase-independent cell death mediator, apoptosis-inducing factor (AIF release from mitochondria and nuclear translocation in a ROS production-dependent manner. Amelioration of berberine-stimulated ROS production or suppression of AIF expression blocked berberine-induced cell death and LDH release in IMCE cells. Furthermore, two targets of ROS production in cells, cathepsin B release from lysosomes and PARP activation were induced by berberine. Blockage of either of these pathways decreased berberine-induced AIF activation and cell death in IMCE cells. Thus, berberine-stimulated ROS production leads to cathepsin B release and PARP activation-dependent AIF activation, resulting in caspase-independent cell death in colon tumor cells. Notably, normal colon epithelial cells are less susceptible to berberine-induced cell death, which suggests the specific inhibitory effects of berberine on colon tumor cell growth.

  20. Artesunate induces AIF-dependent apoptosis in A549 cells

    Science.gov (United States)

    Zhou, Chen-juan; Chen, Tong-Sheng

    2012-03-01

    Artesunate (ART), a semi-synthetic derivative of the sesquiterpene artemisinin extracted from the Chinese herb Artemisia annua, exerts a broad spectrum of clinical activity against human cancers. It has been shown that ART induces cancer cells death through apoptosis pathway. This study investigated whether ART treatment induced reactive oxygen species (ROS)-dependent cell death in the apoptosis fashion in human lung adenocarconoma A549 cell line and the proapoptotic protein apoptosis inducing factor (AIF) is involved in ART-induced apoptosis. Cells treated with ART exhibited typical apoptotic morphology as chromatin condensation, margination and shrunken nucleus. ART treatment also induced a loss of mitochondrial membrane potential and AIF release from mitochondria. Silencing AIF can remarkable attenuated ART-induced apoptosis. Collectively, ART induces apoptosis by caspase-independent intrinsic pathway in A549 cells.

  1. Sensitization of radiation-induced cell death by genistein

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Tae Rim; Kim, In Gyu [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2010-03-15

    A number of epidemiological studies as well as biological experiments, showed that genistein, one of the isoflavone, prevents prostate cancer occurrence. In this study, we showed that genistein inhibited the cell proliferation of human promyeoltic leukemia HL-60 cells and induced G2/M phase arrest. In addition, combination of genistein treatment and {gamma}-irradiation displayed synergistic effect in apoptotic cell death of HL-60 cells. This means that the repair of genistein-induced DNA damage was hindered by {gamma}-irradiation and thus cell death was increased. In conclusion, genistein is one of the important chemicals that sensitize radiation-induced cell death.

  2. Ultrastructure and immunocytochemical characteristics of cells in the octopus cell area of the rat cochlear nucleus: comparison with multipolar cells.

    Science.gov (United States)

    Alibardi, Lorenzo

    2003-01-01

    Cells in the octopus cell area of the rat ventral cochlear nucleus have been connected to the monaural interpretation of spectral patterns of sound such as those derived from speech. This is possible by their fast onset of firing after each octopus cell and its dendrites have been contacted by many auditory fibres carrying different frequencies. The cytological characteristics that make these large cells able to perform such a function have been studied with ultrastructural immunocytochemistry for glycine, GABA and glutamate, and compared to that of other multipolar neurons of other regions of the ventral cochlear nucleus. Cells in the octopus cell area have an ultrastructure similar to large-giant D-multipolar neurons present in other areas of the cochlear nucleus, from which they differ by the presence of a larger excitatory axo-somatic synaptic input and larger mitochondria. Octopus cells are glycine and GABA negative, and glutamate positive with different degree. Large octopus cells receive more axo-somatic boutons than smaller octopus cells. Fusiform octopus cells are found sparsely within the intermediate acoustic striae. These cells are large to giant excitatory neurons (23-35 microm) with 62-85% of their irregular perimeter covered with large axo-somatic synaptic boutons. Most boutons contain round vesicles and are glycine and GABA negative but glutamate positive. The latter excitatory boutons represent about 70% of the input to octopus cells. Glycine positive boutons with flat and pleomorphic vesicles account for 9-10% of the input while GABA-ergic boutons with pleomorphic vesicles represent about 20% of the synaptic input. Other few, multipolar cells within the rat octopus cell area are surrounded by more inhibitory than excitatory terminals which contain flat and pleomorphic vesicles, a feature distinctive from that of true octopus cells. The latter resemble multipolar cells seen outside the octopus cell area that project to the contralateral inferior

  3. Induced adult stem (iAS) cells and induced transit amplifying progenitor (iTAP) cells-a possible alternative to induced pluripotent stem (iPS) cells?

    Science.gov (United States)

    Heng, Boon Chin; Richards, Mark; Ge, Zigang; Shu, Yimin

    2010-02-01

    The successful derivation of iPSC lines effectively demonstrates that it is possible to reset the 'developmental clock' of somatic cells all the way back to the initial embryonic state. Hence, it is plausible that this clock may instead be turned back half-way to a less immature developmental stage that is more directly applicable to clinical therapeutic applications or for in vitro pharmacology/toxicology screening assays. Such a suitable developmental state is postulated to be either the putative transit amplifying progenitor stage or adult stem cell stage. It is hypothetically possible to reprogram mature and terminally differentiated somatic cells back to the adult stem cell or transit amplifying progenitor stage, in a manner similar to the derivation of iPSC. It is proposed that the terminology 'Induced Adult Stem Cells' (iASC) or 'Induced Transit Amplifying Progenitor Cells' (iTAPC) be used to described such reprogrammed somatic cells. Of particular interest, is the possibility of resetting the developmental clock of mature differentiated somatic cells of the mesenchymal lineage, explanted from adipose tissue, bone marrow and cartilage. The putative adult stem cell sub-population from which these cells are derived, commonly referred to as 'mesenchymal stem cells', are highly versatile and hold much therapeutic promise in regenerative medicine, as attested to by numerous human clinical trials and animal studies. Perhaps it may be appropriate to term such reprogrammed cells as 'Induced Mesenchymal Stem Cells' (iMSC) or as 'Induced Mesenchumal Progenitor Cells' (iMPC). Given that cells from the same organ/tissue will share some commonalities in gene expression, we hypothesize that the generation of iASC or iTAPC would be more efficient as compared to iPSC generation, since a common epigenetic program must exist between the reprogrammed cells, adult stem cell or progenitor cell types and terminally differentiated cell types from the same organ/tissue.

  4. α-Mangostin Induces Apoptosis and Cell Cycle Arrest in Oral Squamous Cell Carcinoma Cell

    Science.gov (United States)

    Kwak, Hyun-Ho; Park, Bong-Soo

    2016-01-01

    Mangosteen has long been used as a traditional medicine and is known to have antibacterial, antioxidant, and anticancer effects. Although the effects of α-mangostin, a natural compound extracted from the pericarp of mangosteen, have been investigated in many studies, there is limited data on the effects of the compound in human oral squamous cell carcinoma (OSCC). In this study, α-mangostin was assessed as a potential anticancer agent against human OSCC cells. α-Mangostin inhibited cell proliferation and induced cell death in OSCC cells in a dose- and time-dependent manner with little to no effect on normal human PDLF cells. α-Mangostin treatment clearly showed apoptotic evidences such as nuclear fragmentation and accumulation of annexin V and PI-positive cells on OSCC cells. α-Mangostin treatment also caused the collapse of mitochondrial membrane potential and the translocation of cytochrome c from the mitochondria into the cytosol. The expressions of the mitochondria-related proteins were activated by α-mangostin. Treatment with α-mangostin also induced G1 phase arrest and downregulated cell cycle-related proteins (CDK/cyclin). Hence, α-mangostin specifically induces cell death and inhibits proliferation in OSCC cells via the intrinsic apoptosis pathway and cell cycle arrest at the G1 phase, suggesting that α-mangostin may be an effective agent for the treatment of OSCC. PMID:27478478

  5. α-Mangostin Induces Apoptosis and Cell Cycle Arrest in Oral Squamous Cell Carcinoma Cell

    Directory of Open Access Journals (Sweden)

    Hyun-Ho Kwak

    2016-01-01

    Full Text Available Mangosteen has long been used as a traditional medicine and is known to have antibacterial, antioxidant, and anticancer effects. Although the effects of α-mangostin, a natural compound extracted from the pericarp of mangosteen, have been investigated in many studies, there is limited data on the effects of the compound in human oral squamous cell carcinoma (OSCC. In this study, α-mangostin was assessed as a potential anticancer agent against human OSCC cells. α-Mangostin inhibited cell proliferation and induced cell death in OSCC cells in a dose- and time-dependent manner with little to no effect on normal human PDLF cells. α-Mangostin treatment clearly showed apoptotic evidences such as nuclear fragmentation and accumulation of annexin V and PI-positive cells on OSCC cells. α-Mangostin treatment also caused the collapse of mitochondrial membrane potential and the translocation of cytochrome c from the mitochondria into the cytosol. The expressions of the mitochondria-related proteins were activated by α-mangostin. Treatment with α-mangostin also induced G1 phase arrest and downregulated cell cycle-related proteins (CDK/cyclin. Hence, α-mangostin specifically induces cell death and inhibits proliferation in OSCC cells via the intrinsic apoptosis pathway and cell cycle arrest at the G1 phase, suggesting that α-mangostin may be an effective agent for the treatment of OSCC.

  6. Erythroid differentiation of human induced pluripotent stem cells is independent of donor cell type of origin.

    Science.gov (United States)

    Dorn, Isabel; Klich, Katharina; Arauzo-Bravo, Marcos J; Radstaak, Martina; Santourlidis, Simeon; Ghanjati, Foued; Radke, Teja F; Psathaki, Olympia E; Hargus, Gunnar; Kramer, Jan; Einhaus, Martin; Kim, Jeong Beom; Kögler, Gesine; Wernet, Peter; Schöler, Hans R; Schlenke, Peter; Zaehres, Holm

    2015-01-01

    Epigenetic memory in induced pluripotent stem cells, which is related to the somatic cell type of origin of the stem cells, might lead to variations in the differentiation capacities of the pluripotent stem cells. In this context, induced pluripotent stem cells from human CD34(+) hematopoietic stem cells might be more suitable for hematopoietic differentiation than the commonly used fibroblast-derived induced pluripotent stem cells. To investigate the influence of an epigenetic memory on the ex vivo expansion of induced pluripotent stem cells into erythroid cells, we compared induced pluripotent stem cells from human neural stem cells and human cord blood-derived CD34(+) hematopoietic stem cells and evaluated their potential for differentiation into hematopoietic progenitor and mature red blood cells. Although genome-wide DNA methylation profiling at all promoter regions demonstrates that the epigenetic memory of induced pluripotent stem cells is influenced by the somatic cell type of origin of the stem cells, we found a similar hematopoietic induction potential and erythroid differentiation pattern of induced pluripotent stem cells of different somatic cell origin. All human induced pluripotent stem cell lines showed terminal maturation into normoblasts and enucleated reticulocytes, producing predominantly fetal hemoglobin. Differences were only observed in the growth rate of erythroid cells, which was slightly higher in the induced pluripotent stem cells derived from CD34(+) hematopoietic stem cells. More detailed methylation analysis of the hematopoietic and erythroid promoters identified similar CpG methylation levels in the induced pluripotent stem cell lines derived from CD34(+) cells and those derived from neural stem cells, which confirms their comparable erythroid differentiation potential.

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

    DEFF Research Database (Denmark)

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

    1998-01-01

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

  8. Laser-induced lipolysis on adipose cells

    Science.gov (United States)

    Solarte, Efrain; Gutierrez, O.; Neira, Rodrigo; Arroyave, J.; Isaza, Carolina; Ramirez, Hugo; Rebolledo, Aldo F.; Criollo, Willian; Ortiz, C.

    2004-10-01

    Recently, a new liposuction technique, using a low-level laser (LLL) device and Ultrawet solution prior to the procedure, demonstrated the movement of fat from the inside to the outside of the adipocyte (Neira et al., 2002). To determine the mechanisms involved, we have performed Scanning and Transmission Electron Microscopy studies; Light transmittance measurements on adipocyte dilutions; and a study of laser light propagation in adipose tissue. This studies show: 1. Cellular membrane alterations. 2. LLL is capable to reach the deep adipose tissue layer, and 3. The tumescence solution enhances the light propagation by clearing the tissue. MRI studies demonstrated the appearance of fat on laser treated abdominal tissue. Besides, adipocytes were cultivated and irradiated to observe the effects on isolated cells. These last studies show: 1. 635 nm-laser alone is capable of mobilizing cholesterol from the cell membrane; this action is enhanced by the presence of adrenaline and lidocaine. 2. Intracellular fat is released from adipocytes by co joint action of adrenaline, aminophyline and 635 nm-laser. Results are consistent with a laser induced cellular process, which causes fat release from the adipocytes into the intercellular space, besides the modification of the cellular membranes.

  9. Perovskite Solar Cells with Large-Area CVD-Graphene for Tandem Solar Cells.

    Science.gov (United States)

    Lang, Felix; Gluba, Marc A; Albrecht, Steve; Rappich, Jörg; Korte, Lars; Rech, Bernd; Nickel, Norbert H

    2015-07-16

    Perovskite solar cells with transparent contacts may be used to compensate for thermalization losses of silicon solar cells in tandem devices. This offers a way to outreach stagnating efficiencies. However, perovskite top cells in tandem structures require contact layers with high electrical conductivity and optimal transparency. We address this challenge by implementing large-area graphene grown by chemical vapor deposition as a highly transparent electrode in perovskite solar cells, leading to identical charge collection efficiencies. Electrical performance of solar cells with a graphene-based contact reached those of solar cells with standard gold contacts. The optical transmission by far exceeds that of reference devices and amounts to 64.3% below the perovskite band gap. Finally, we demonstrate a four-terminal tandem device combining a high band gap graphene-contacted perovskite top solar cell (Eg = 1.6 eV) with an amorphous/crystalline silicon bottom solar cell (Eg = 1.12 eV).

  10. Generation of dendritic cells and macrophages from human induced pluripotent stem cells aiming at cell therapy.

    Science.gov (United States)

    Senju, S; Haruta, M; Matsumura, K; Matsunaga, Y; Fukushima, S; Ikeda, T; Takamatsu, K; Irie, A; Nishimura, Y

    2011-09-01

    This report describes generation of dendritic cells (DCs) and macrophages from human induced pluripotent stem (iPS) cells. iPS cell-derived DC (iPS-DC) exhibited the morphology of typical DC and function of T-cell stimulation and antigen presentation. iPS-DC loaded with cytomegalovirus (CMV) peptide induced vigorous expansion of CMV-specific autologous CD8+ T cells. Macrophages (iPS-MP) with activity of zymosan phagocytosis and C5a-induced chemotaxis were also generated from iPS cells. Genetically modified iPS-MPs were generated by the introduction of expression vectors into undifferentiated iPS cells, isolation of transfectant iPS cell clone and subsequent differentiation. By this procedure, we generated iPS-MP expressing a membrane-bound form of single chain antibody (scFv) specific to amyloid β (Aβ), the causal protein of Alzheimer's disease. The scFv-transfectant iPS-MP exhibited efficient Aβ-specific phagocytosis activity. iPS-MP expressing CD20-specific scFv engulfed and killed BALL-1 B-cell leukemia cells. Anti-BALL-1 effect of iPS-MP in vivo was demonstrated in a xeno-transplantation model using severe combined immunodeficient mice. In addition, we established a xeno-free culture protocol to generate iPS-DC and iPS-MP. Collectively, we demonstrated the possibility of application of iPS-DC and macrophages to cell therapy.

  11. Characterization of Entamoeba histolytica-induced dephosphorylation in Jurkat cells

    Indian Academy of Sciences (India)

    J E Teixeira; B J Mann

    2002-11-01

    Entamoeba histolytica killing of host cells is contact dependent and mediated by a Gal/GalNAc lectin. Upon contact with amoeba a rapid and extensive dephosphorylation of tyrosine phosphorylated host cell proteins is observed. This effect is mediated by the Gal/GalNAc lectin. However, it requires intact cells, as purified lectin failed to induce dephosphorylation in Jurkat cells. The nonpathogenic, but morphologically identical amoeba, Entamoeba moshkovskii also did not induce dephosphorylation in target cells. Treatment of Jurkat cells with phosphotyrosine phosphatase inhibitors has shown that a host phosphatase is responsible for dephosphorylation. However, it was found that the CD45 phosphotase was not necessary for dephosphorylation of host cell proteins.

  12. HIV transcription is induced with some forms of cell killing

    Energy Technology Data Exchange (ETDEWEB)

    Woloschak, G.E. [Argonne National Lab., IL (United States); Schreck, S. [Argonne National Lab., IL (United States)][South Carolina Univ., Columbia, SC (United States). Dept. of Chemistry; Panozzo, J. [Loyola Univ. Medical Center, Maywood, IL (United States); Chang-Liu, C.-M. [Argonne National Lab., IL (United States); Libertin, C.R. [Loyola Univ. Medical Center, Maywood, IL (United States)

    1996-11-01

    Using HeLa cells stably transfected with an HIV-LTR-CAT construct`, we demonstrated a peak in CAT induction that occurs in viable (but not necessarily cell-division-competent) cells 24 h following exposure to some cell-killing agents. {Gamma} rays were the only cell-killing agent which did not induce HIV transcription; this can be attributed to the fact that {gamma}-ray-induced apoptotic death requires function p53, which is missing in HeLa cells. For all other agents, HIV-LTR induction was dose-dependent and correlated with the amount of cell killing that occurred in the culture.

  13. Constitutive CD40L expression on B cells prematurely terminates germinal center response and leads to augmented plasma cell production in T cell areas.

    Science.gov (United States)

    Bolduc, Anna; Long, Eugene; Stapler, Dale; Cascalho, Marilia; Tsubata, Takeshi; Koni, Pandelakis A; Shimoda, Michiko

    2010-07-01

    CD40/CD40L engagement is essential to T cell-dependent B cell proliferation and differentiation. However, the precise role of CD40 signaling through cognate T-B interaction in the generation of germinal center and memory B cells is still incompletely understood. To address this issue, a B cell-specific CD40L transgene (CD40LBTg) was introduced into mice with B cell-restricted MHC class II deficiency. Using this mouse model, we show that constitutive CD40L expression on B cells alone could not induce germinal center differentiation of MHC class II-deficient B cells after immunization with T cell-dependent Ag. Thus, some other MHC class II-dependent T cell-derived signals are essential for the generation of germinal center B cells in response to T cell-dependent Ag. In fact, CD40LBTg mice generated a complex Ag-specific IgG1 response, which was greatly enhanced in early, but reduced in late, primary response compared with control mice. We also found that the frequency of Ag-specific germinal center B cells in CD40LBTg mice was abruptly reduced 1 wk after immunization. As a result, the numbers of Ag-specific IgG1 long-lived plasma cells and memory B cells were reduced. By histology, large numbers of Ag-specific plasma cells were found in T cell areas adjacent to Ag-specific germinal centers of CD40LBTg mice, temporarily during the second week of primary response. These results indicate that CD40L expression on B cells prematurely terminated their ongoing germinal center response and produced plasma cells. Our results support the notion that CD40 signaling is an active termination signal for germinal center reaction.

  14. Mangiferin induces cell death against rhabdomyosarcoma through sustained oxidative stress

    OpenAIRE

    Vishwanadha Vijaya Padma; Palanisamy Kalaiselvi; Rangasamy Yuvaraj; M. Rabeeth

    2015-01-01

    Background: Embryonic rhabdomyosarcoma (RD) is the most prevalent type of cancer among children. The present study aimed to investigate cell death induced by mangiferin in RD cells. Methods: The Inhibitory concentration (IC50) value of mangiferin was determined by an MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide) assay. Cell death induced by mangiferin against RD cells was determined through lactate dehydrogenase and nitric oxide release, intracellular calcium levels, r...

  15. Cannabinoids induce incomplete maturation of cultured human leukemia cells

    Energy Technology Data Exchange (ETDEWEB)

    Murison, G.; Chubb, C.B.H.; Maeda, S.; Gemmell, M.A.; Huberman, E.

    1987-08-01

    Monocyte maturation markers were induced in cultured human myeloblastic ML-2 leukemia cells after treatment for 1-6 days with 0.03-30 ..mu..M ..delta../sup 9/-tetrahydrocannabinol (THC), the major psychoactive component of marijuana. After a 2-day or longer treatment, 2- to 5-fold increases were found in the percentages of cells exhibiting reactivity with either the murine OKM1 monoclonal antibody of the Leu-M5 monoclonal antibody, staining positively for nonspecific esterase activity, and displaying a promonocyte morphology. The increases in these differentiation markers after treatment with 0.03-1 ..mu..M THC were dose dependent. At this dose range, THC did not cause an inhibition of cell growth. The THC-induced cell maturation was also characterized by specific changes in the patterns of newly synthesized proteins. The THC-induced differentiation did not, however, result in cells with a highly developed mature monocyte phenotype. However, treatment of these incompletely matured cells with either phorbol 12-myristate 13-acetate of 1..cap alpha..,25-dihydroxycholecalciferol, which are inducers of differentiation in myeloid leukemia cells (including ML-2 cells), produced cells with a mature monocyte morphology. The ML-2 cell system described here may be a useful tool for deciphering critical biochemical events that lead to the cannabinoid-induced incomplete cell differentiation of ML-2 cells and other related cell types. Findings obtained from this system may have important implications for studies of cannabinoid effects on normal human bone-marrow progenitor cells.

  16. Effect of chaetocin on renal cell carcinoma cells and cytokine-induced killer cells

    Directory of Open Access Journals (Sweden)

    Rombo, Roman

    2016-04-01

    Full Text Available We examined the cytotoxic effects of chaetocin on clear cell renal cell carcinoma (ccRCC cells and the possibility to combine the effects of chaetocin with the effects of cytokine-induced killer cells (CIK assayed by MTT assay and FACS analysis. Chaetocin is a thiodioxopiperazine produced by fungi belonging to the chaetomiaceae family. In 2007, it was first reported that chaetocin shows potent and selectiveanti-cancer activity by inducing reactive oxygen species. CIK cells are generated from CD3+/CD56- T lymphocytes with double negative phenotype that are isolated from human blood. The addition of distinct interleukins and antibodies results in the generation of CIK cells that are able to specifically target and destroy renal carcinoma cells. The results of this research state that the anti-ccRCC activity of chaetocin is weak and does not show a high grade of selectivity on clear cell renal cell carcinoma cells. Although the CIK cells show a high grade of selective anti-ccRCC activity, this effect could not be improved by the addition of chaetocin. So chaetocin seems to be no suitable agent for specific targeting ccRCC cells or for the combination therapy with CIK cells in renal cancer.

  17. Glial cell derived neurotrophic factor induces spermatogonial stem cell marker genes in chicken mesenchymal stem cells.

    Science.gov (United States)

    Boozarpour, Sohrab; Matin, Maryam M; Momeni-Moghaddam, Madjid; Dehghani, Hesam; Mahdavi-Shahri, Naser; Sisakhtnezhad, Sajjad; Heirani-Tabasi, Asieh; Irfan-Maqsood, Muhammad; Bahrami, Ahmad Reza

    2016-06-01

    Mesenchymal stem cells (MSCs) are known with the potential of multi-lineage differentiation. Advances in differentiation technology have also resulted in the conversion of MSCs to other kinds of stem cells. MSCs are considered as a suitable source of cells for biotechnology purposes because they are abundant, easily accessible and well characterized cells. Nowadays small molecules are introduced as novel and efficient factors to differentiate stem cells. In this work, we examined the potential of glial cell derived neurotrophic factor (GDNF) for differentiating chicken MSCs toward spermatogonial stem cells. MSCs were isolated and characterized from chicken and cultured under treatment with all-trans retinoic acid (RA) or glial cell derived neurotrophic factor. Expression analysis of specific genes after 7days of RA treatment, as examined by RT-PCR, proved positive for some germ cell markers such as CVH, STRA8, PLZF and some genes involved in spermatogonial stem cell maintenance like BCL6b and c-KIT. On the other hand, GDNF could additionally induce expression of POU5F1, and NANOG as well as other genes which were induced after RA treatment. These data illustrated that GDNF is relatively more effective in diverting chicken MSCs towards Spermatogonial stem cell -like cells in chickens and suggests GDNF as a new agent to obtain transgenic poultry, nevertheless, exploitability of these cells should be verified by more experiments.

  18. Generation of human induced pluripotent stem cells from dermal fibroblasts

    OpenAIRE

    2008-01-01

    The generation of patient-specific pluripotent stem cells has the potential to accelerate the implementation of stem cells for clinical treatment of degenerative diseases. Technologies including somatic cell nuclear transfer and cell fusion might generate such cells but are hindered by issues that might prevent them from being used clinically. Here, we describe methods to use dermal fibroblasts easily obtained from an individual human to generate human induced pluripotent stem (iPS) cells by ...

  19. Clozapine Induces Autophagic Cell Death in Non-Small Cell Lung Cancer Cells

    Directory of Open Access Journals (Sweden)

    Yu-Chun Yin

    2015-02-01

    Full Text Available Background/Aims: Previous studies have shown that patients with schizophrenia have a lower incidence of cancer than the general population, and several antipsychotics have been demonstrated to have cytotoxic effects on cancer cells. However, the mechanisms underlying these results remain unclear. The present study aimed to investigate the effect of clozapine, which is often used to treat patients with refractory schizophrenia, on the growth of non-small cell lung carcinoma cell lines and to examine whether autophagy contributes to its effects. Methods: A549 and H1299 cells were treated with clozapine, and cell cytotoxicity, cell cycle and autophagy were then assessed. The autophagy inhibitor bafilomycin A1 and siRNA-targeted Atg7 were used to determine the role of autophagy in the effect of clozapine. Results: Clozapine inhibited A549 and H1299 proliferation and increased p21 and p27 expression levels, leading to cell cycle arrest. Clozapine also induced a high level of autophagy, but not apoptosis, in both cell lines, and the growth inhibitory effect of clozapine was blunted by treatment with the autophagy inhibitor bafilomycin A1 or with an siRNA targeting atg7. Conclusions: Clozapine inhibits cell proliferation by inducing autophagic cell death in two non-small cell lung carcinoma cell lines. These findings may provide insights into the relationship between clozapine use and the lower incidence of lung cancer among patients with schizophrenia.

  20. Production of Induced Pluripotent Stem Cells by Reprogramming of Blood Cells

    Directory of Open Access Journals (Sweden)

    Sadia Zia

    2011-06-01

    Full Text Available Blood cells are the simple, efficient and economical source for the production of induced pluripotent cells. The discovery of induced pluripotent cells was not novel; it was pedestal on the scientific principals and technologies which have been developed over last six decades. These are nuclear transfer and the cloning of Animals, Pluripotent cell lines and fusion hybrids and Transcription Factors and lineage switching. The use of human embryonic stem cells in regenerative medicines was a breakthrough but make use of these cells arise ethical issues as they are obtained from human embryos. An alternative advancement using induced pluripotent stem cells, which mimics the embryonic stem cells has the significant gain that they replaced the embryonic stem cells. The pluripotent cells can be induced from terminally differentiated somatic cells by the Induction of only four defined factors including c-Myc, klf4, Oct4 and Sox2 which are enough to alter the fate of cell.

  1. Aggregatibacter actinomycetemcomitans induces Th17 cells in atherosclerotic lesions.

    Science.gov (United States)

    Jia, Ru; Hashizume-Takizawa, Tomomi; Du, Yuan; Yamamoto, Masafumi; Kurita-Ochiai, Tomoko

    2015-04-01

    Th17 cells have been linked to the pathogenesis of several chronic inflammatory and autoimmune diseases. However, the role of Th17 cells and IL-17 in atherosclerosis remains poorly understood. We previously reported that Aggregatibacter actinomycetemcomitans (Aa) bacteremia accelerated atherosclerosis accompanied by inflammation in apolipoprotein E-deficient spontaneously hyperlipidemic (Apoe(shl)) mice. In this study, we investigated whether Aa promotes the Th17 inducing pathway in Aa-challenged Apoe(shl) mice. Mice were intravenously injected with live Aa HK1651 or vehicles. Time-course analysis of splenic IL-17(+)CD4(+) cell frequencies, the proximal aorta lesion area, serum IL-17, IL-6, TGF-β and IL-1β levels, the mRNA expression of Th17-related molecules such as IL-1β, IL-6, IL17RA, STAT3, IL-21, IL-23, TGF-β and RORγt, Th17-related microRNA levels and the levels of AIM-2, Mincle and NLRP3 were examined. Challenge with Aa time dependently induced tropism of Th17 cells in the spleen and increase in atheromatous lesions in the aortic sinus of Apoe(shl) mice. Serum IL-17, IL-6, TGF-β and IL-1β levels were significantly enhanced by Aa. The gene expression of IL-1β, IL-6, IL-17RA, IL-21, IL-23, TGF-β, STAT3, RORγt, AIM-2, Mincle and NLRP3 was also time dependently stimulated in the aorta of Aa-challenged mice. Furthermore, Aa challenge significantly increased the expression of miR-146b and miR-155 in the aorta. Based on the results, it seems that Aa stimulates Th17 induction that affects the progression of Aa-accelerated atherosclerosis.

  2. Semantic Wavelet-Induced Frequency-Tagging (SWIFT) Periodically Activates Category Selective Areas While Steadily Activating Early Visual Areas.

    Science.gov (United States)

    Koenig-Robert, Roger; VanRullen, Rufin; Tsuchiya, Naotsugu

    2015-01-01

    Primate visual systems process natural images in a hierarchical manner: at the early stage, neurons are tuned to local image features, while neurons in high-level areas are tuned to abstract object categories. Standard models of visual processing assume that the transition of tuning from image features to object categories emerges gradually along the visual hierarchy. Direct tests of such models remain difficult due to confounding alteration in low-level image properties when contrasting distinct object categories. When such contrast is performed in a classic functional localizer method, the desired activation in high-level visual areas is typically accompanied with activation in early visual areas. Here we used a novel image-modulation method called SWIFT (semantic wavelet-induced frequency-tagging), a variant of frequency-tagging techniques. Natural images modulated by SWIFT reveal object semantics periodically while keeping low-level properties constant. Using functional magnetic resonance imaging (fMRI), we indeed found that faces and scenes modulated with SWIFT periodically activated the prototypical category-selective areas while they elicited sustained and constant responses in early visual areas. SWIFT and the localizer were selective and specific to a similar extent in activating category-selective areas. Only SWIFT progressively activated the visual pathway from low- to high-level areas, consistent with predictions from standard hierarchical models. We confirmed these results with criterion-free methods, generalizing the validity of our approach and show that it is possible to dissociate neural activation in early and category-selective areas. Our results provide direct evidence for the hierarchical nature of the representation of visual objects along the visual stream and open up future applications of frequency-tagging methods in fMRI.

  3. Entamoeba histolytica induces cell death of HT29 colonic epithelial cells via NOX1-derived ROS.

    Science.gov (United States)

    Kim, Kyeong Ah; Kim, Ju Young; Lee, Young Ah; Min, Arim; Bahk, Young Yil; Shin, Myeong Heon

    2013-02-01

    Entamoeba histolytica, which causes amoebic colitis and occasionally liver abscess in humans, is able to induce host cell death. However, signaling mechanisms of colon cell death induced by E. histolytica are not fully elucidated. In this study, we investigated the signaling role of NOX in cell death of HT29 colonic epithelial cells induced by E. histolytica. Incubation of HT29 cells with amoebic trophozoites resulted in DNA fragmentation that is a hallmark of apoptotic cell death. In addition, E. histolytica generate intracellular reactive oxygen species (ROS) in a contact-dependent manner. Inhibition of intracellular ROS level with treatment with DPI, an inhibitor of NADPH oxidases (NOXs), decreased Entamoeba-induced ROS generation and cell death in HT29 cells. However, pan-caspase inhibitor did not affect E. histolytica-induced HT29 cell death. In HT29 cells, catalytic subunit NOX1 and regulatory subunit Rac1 for NOX1 activation were highly expressed. We next investigated whether NADPH oxidase 1 (NOX1)-derived ROS is closely associated with HT29 cell death induced by E. histolytica. Suppression of Rac1 by siRNA significantly inhibited Entamoeba-induced cell death. Moreover, knockdown of NOX1 by siRNA, effectively inhibited E. histolytica-triggered DNA fragmentation in HT29 cells. These results suggest that NOX1-derived ROS is required for apoptotic cell death in HT29 colon epithelial cells induced by E. histolytica.

  4. Alpha-particles induce autophagy in multiple myeloma cells

    Directory of Open Access Journals (Sweden)

    Joelle Marcelle Gaschet

    2015-10-01

    Full Text Available Objectives: Radiations emitted by the radionuclides in radioimmunotherapy (RIT approaches induce direct killing of the targeted cells as well as indirect killing through bystander effect. Our research group is dedicated to the development of α-RIT, i.e RIT using α-particles especially for the treatment of multiple myeloma (MM. γ-irradiation and β-irradiation have been shown to trigger apoptosis in tumor cells. Cell death mode induced by 213Bi α-irradiation appears more controversial. We therefore decided to investigate the effects of 213Bi on MM cell radiobiology, notably cell death mechanisms as well as tumor cell immunogenicity after irradiation.Methods: Murine 5T33 and human LP-1 multiple myeloma (MM cell lines were used to study the effects of such α-particles. We first examined the effects of 213Bi on proliferation rate, double strand DNA breaks, cell cycle and cell death. Then, we investigated autophagy after 213Bi irradiation. Finally, a co-culture of dendritic cells (DC with irradiated tumour cells or their culture media was performed to test whether it would induce DC activation.Results: We showed that 213Bi induces DNA double strand breaks, cell cycle arrest and autophagy in both cell lines but we detected only slight levels of early apoptosis within the 120 hours following irradiation in 5T33 and LP-1. Inhibition of autophagy prevented 213Bi induced inhibition of proliferation in LP-1 suggesting that this mechanism is involved in cell death after irradiation. We then assessed the immunogenicity of irradiated cells and found that irradiated LP-1 can activate DC through the secretion of soluble factor(s, however no increase in membrane or extracellular expression of danger associated molecular patterns (DAMPs was observed after irradiation.Conclusion: This study demonstrates that 213Bi induces mainly necrosis in MM cells, low levels of apoptosis and also autophagy that might be involved in tumor cell death.

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

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

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

  6. The apoptosis of HEL cells induced by hydroxyures

    Institute of Scientific and Technical Information of China (English)

    GUICHANGYUN; CHUJIANG; 等

    1997-01-01

    Hydroxyurea has been used to synchronize cultured cells to S-phase and used to treat patients with sicklecell anemia.Recently,we found that hydroxyurea can induce the apoptosis of HEL(human erythroleukemia) cells.The induced HEL cells showed ultrastructurally chromatin condensation with regular crescents at the nuclear edges and apoptotic bodies.However,the cells of K562,another human erythroleukemia cell line,did not show such morphological changes.Under fluoroscope,the HEL cells after induction of ten displayed a clear reduction in nuclear diameter and nuclear chromatin cleavage and condensation and the presence of nuclear ring and apoptotic bodies.Analysis with flow cytometry showed that the percentage of apoptotic cells is about 30-40% after HEL cells were induced by hydroxyurea for 3 days.DNA ladder can be observed by electrophoretic analysis.

  7. Clonal Expansion and Cytotoxicity of TCRVβ Subfamily T Cells Induced by CML and K562 Cells

    Institute of Scientific and Technical Information of China (English)

    YupingZHang; YangqiuLi; ShaohuaChen; LijianYang; GengxinLuo; XueliZhang

    2004-01-01

    OBJECTIVE To investigate the anti-leukemia effect, the distribution and clonal expansion of TCRVβ subfamily T cells in T cells from cord blood and adult peripheral blood induced by CML cells and K562 cells in vitro. METHODS Peripheral blood T cells from one adult donor and 3 cases of cord blood were stimulated with CML cells and K562 cells and further amplified by a suspended T cell-bulk culture,in order to induce CML specific cytotoxic T lymphocytes. The induced T cells were further analyzed for the specific cytotoxicity in CML by LDH assay, the phenotype identification by indirect immunofiuorescence technique and the distribution and clonal expansion of TCRVβ subfamily by using reverse transcriptase-polymerase chain reaction (RT-PCR) and genescan analysis, respectively. RESULTS Oligoclonal and oligoclonal tendency T cells with higher specific cytotoxicity from cord blood and adult peripheral blood could be induced by stimulation with CML cells and K562 cells. CONCLUSIONS Specific cytotoxic T cells for an anti-CML effect could be induced by CML cells and K562 cells .The induced T cells which have the characteristic of specific cytotoxicity against CML cells may come from the clonal expansion of TCRVβ subfamily T cells.

  8. Polyphosphate induces matrix metalloproteinase-3-mediated proliferation of odontoblast-like cells derived from induced pluripotent stem cells

    Energy Technology Data Exchange (ETDEWEB)

    Ozeki, Nobuaki; Hase, Naoko; Yamaguchi, Hideyuki; Hiyama, Taiki; Kawai, Rie [Department of Endodontics, School of Dentistry, Aichi Gakuin University, 2-11 Suemori-dori, Chikusa-ku, Nagoya, Aichi 464-8651 (Japan); Kondo, Ayami [Department of Medicinal Biochemistry, School of Pharmacy, Aichi Gakuin University, 1-100 Kusumoto, Chikusa-ku, Nagoya 464-8650 (Japan); Nakata, Kazuhiko [Department of Endodontics, School of Dentistry, Aichi Gakuin University, 2-11 Suemori-dori, Chikusa-ku, Nagoya, Aichi 464-8651 (Japan); Mogi, Makio, E-mail: makio@dpc.agu.ac.jp [Department of Medicinal Biochemistry, School of Pharmacy, Aichi Gakuin University, 1-100 Kusumoto, Chikusa-ku, Nagoya 464-8650 (Japan)

    2015-05-01

    Inorganic polyphosphate [Poly(P)] may represent a physiological source of phosphate and has the ability to induce bone differentiation in osteoblasts. We previously reported that cytokine-induced matrix metalloproteinase (MMP)-3 accelerates the proliferation of purified odontoblast-like cells. In this study, MMP-3 small interfering RNA (siRNA) was transfected into odontoblast-like cells derived from induced pluripotent stem cells to investigate whether MMP-3 activity is induced by Poly(P) and/or is associated with cell proliferation and differentiation into odontoblast-like cells. Treatment with Poly(P) led to an increase in both cell proliferation and additional odontoblastic differentiation. Poly(P)-treated cells showed a small but significant increase in dentin sialophosphoprotein (DSPP) and dentin matrix protein-1 (DMP-1) mRNA expression, which are markers of mature odontoblasts. The cells also acquired additional odontoblast-specific properties including adoption of an odontoblastic phenotype typified by high alkaline phosphatase (ALP) activity and a calcification capacity. In addition, Poly(P) induced expression of MMP-3 mRNA and protein, and increased MMP-3 activity. MMP-3 siRNA-mediated disruption of the expression of these effectors potently suppressed the expression of odontoblastic biomarkers ALP, DSPP, and DMP-1, and blocked calcification. Interestingly, upon siRNA-mediated silencing of MMP-3, we noted a potent and significant decrease in cell proliferation. Using specific siRNAs, we revealed that a unique signaling cascade, Poly(P)→MMP-3→DSPP and/or DMP-1, was intimately involved in the proliferation of odontoblast-like cells. - Highlights: • Polyphosphate increases proliferation of iPS cell-derived odontoblast-like cells. • Polyphosphate-induced MMP-3 results in an increase of cell proliferation. • Induced cell proliferation involves MMP-3, DSPP, and/or DMP-1 sequentially. • Induced MMP-3 also results in an increase of odontoblastic

  9. Cell autonomy of HIF effects in Drosophila: tracheal cells sense hypoxia and induce terminal branch sprouting.

    Science.gov (United States)

    Centanin, Lázaro; Dekanty, Andrés; Romero, Nuria; Irisarri, Maximiliano; Gorr, Thomas A; Wappner, Pablo

    2008-04-01

    Drosophila tracheal terminal branches are plastic and have the capacity to sprout out projections toward oxygen-starved areas, in a process analogous to mammalian angiogenesis. This response involves the upregulation of FGF/Branchless in hypoxic tissues, which binds its receptor Breathless on tracheal cells. Here, we show that extra sprouting depends on the Hypoxia-Inducible Factor (HIF)-alpha homolog Sima and on the HIF-prolyl hydroxylase Fatiga that operates as an oxygen sensor. In mild hypoxia, Sima accumulates in tracheal cells, where it induces breathless, and this induction is sufficient to provoke tracheal extra sprouting. In nontracheal cells, Sima contributes to branchless induction, whereas overexpression of Sima fails to attract terminal branch outgrowth, suggesting that HIF-independent components are also required for full induction of the ligand. We propose that the autonomous response to hypoxia that occurs in tracheal cells enhances tracheal sensitivity to increasing Branchless levels, and that this mechanism is a cardinal step in hypoxia-dependent tracheal sprouting.

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

    OpenAIRE

    2009-01-01

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

  11. Mathematical Modeling of the Induced Mutation Process in Bacterial Cells

    Science.gov (United States)

    Belov, Oleg V.; Krasavin, Evgeny A.; Parkhomenko, Alexander Yu.

    2010-01-01

    A mathematical model of the ultraviolet (UV) irradiation-induced mutation process in bacterial cells Escherichia coli is developed. Using mathematical approaches, the whole chain of events is tracked from a cell exposure to the damaging factor to mutation formation in the DNA chain. An account of the key special features of the regulation of this genetic network allows predicting the effects induced by the cell exposure to certain UV energy fluence.

  12. Organic Solar Cells Performances Improvement Induced by Interface Buffer Layers

    OpenAIRE

    Bernède, J.C.; Godoy, A.; Cattin, L.; Diaz, F. R.; Morsli, M; Valle, M. A. del

    2010-01-01

    In the last 22 years that have elapsed since the pioneering work of Tang [Tang, Appl. Phys. Lett., 1986], significant improvement in the fundamental understanding and cells construction have led to efficiencies higher than 6%. The new concept of polymer:fullerene BHJ solar cells has allowed dramatic improvements in devices efficiency. It has induced a healthy competition with the multi-heterojunction devices base on small organic molecules, which induces significant progress in both cells fam...

  13. Methylglyoxal Induces Mitochondrial Dysfunction and Cell Death in Liver

    OpenAIRE

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

    2014-01-01

    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 p...

  14. Modelling familial dysautonomia in human induced pluripotent stem cells

    OpenAIRE

    Lee, Gabsang; Studer, Lorenz

    2011-01-01

    Induced pluripotent stem (iPS) cells have considerable promise as a novel tool for modelling human disease and for drug discovery. While the generation of disease-specific iPS cells has become routine, realizing the potential of iPS cells in disease modelling poses challenges at multiple fronts. Such challenges include selecting a suitable disease target, directing the fate of iPS cells into symptom-relevant cell populations, identifying disease-related phenotypes and showing reversibility of...

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

    Energy Technology Data Exchange (ETDEWEB)

    Walia, Rupali; Dardari, Rkia, E-mail: rdardari@ucalgary.ca; 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.

  16. Induced Pluripotent Stem Cells: Characteristics and Perspectives

    Science.gov (United States)

    Cantz, Tobias; Martin, Ulrich

    The induction of pluripotency in somatic cells is widely considered as a major breakthrough in regenerative medicine, because this approach provides the basis for individualized stem cell-based therapies. Moreover, with respect to cell transplantation and tissue engineering, expertise from bioengineering to transplantation medicine is now meeting basic research of stem cell biology.

  17. Palytoxin induces cell lysis by priming a two-step process in mcf-7 cells.

    Science.gov (United States)

    Prandi, Simone; Sala, Gian Luca; Bellocci, Mirella; Alessandrini, Andrea; Facci, Paolo; Bigiani, Albertino; Rossini, Gian Paolo

    2011-08-15

    The cytolytic action of palytoxin (PlTX) was recognized long ago, but its features have remained largely undetermined. We used biochemical, morphological, physiological, and physical tools, to study the cytolytic response in MCF-7 cells, as our model system. Cytolysis represented a stereotyped response induced by the addition of isotonic phosphate buffer (PBS) to cells that had been exposed to PlTX, after toxin removal and under optimal and suboptimal experimental conditions. Cytolysis was sensitive to osmolytes present during cell exposure to PlTX but not in the course of the lytic phase. Fluorescence microscopy showed that PlTX caused cell rounding and rearrangement of the actin cytoskeleton. Atomic force microscopy (AFM) was used to monitor PlTX effects in real time, and we found that morphological and mechanical properties of MCF-7 cells did not change during toxin exposure, but increased cell height and decreased stiffness at its surface were observed when PBS was added to PlTX-treated cells. The presence of an osmolyte during PlTX treatment prevented the detection of changes in morphological and mechanical properties caused by PBS addition to toxin-treated cells, as detected by AFM. By patch-clamp technique, we confirmed that PlTX action involved the transformation of the Na(+),K(+)-ATPase into a channel and found that cell membrane capacitance was not changed by PlTX, indicating that the membrane surface area was not greatly affected in our model system. Overall, our findings show that the cytolytic response triggered by PlTX in MCF-7 cells includes a first phase, which is toxin-dependent and osmolyte-sensitive, priming cells to lytic events taking place in a separate phase, which does not require the presence of the toxin and is osmolyte-insensitive but is accompanied by marked reorganization of actin-based cytoskeleton and altered mechanical properties at the cell's surface. A model of the two-step process of PlTX-induced cytolysis is presented.

  18. Autophagy is associated with cucurbitacin D-induced apoptosis in human T cell leukemia cells.

    Science.gov (United States)

    Nakanishi, Tsukasa; Song, Yuan; He, Cuiying; Wang, Duo; Morita, Kentaro; Tsukada, Junichi; Kanazawa, Tamotsu; Yoshida, Yasuhiro

    2016-04-01

    We previously reported that the inflammasome inhibitor cucurbitacin D (CuD) induces apoptosis in human leukemia cell lines. In the present study, we investigated the effects of co-treatment with an additional Bcl-xL inhibitor, Z36. Treatment with Z36 induced cell death in leukemia cell lines, with MT-4 cells exhibiting the lowest sensitivity to Z36. Co-treatment of cells with Z36 and CuD resulted in a greater degree of cell death for Hut78 and Jurkat cells than treatment with CuD alone. In contrast, co-treatment of MT-4 cells with Z36 and CuD had a suppressive effect on cell death. The autophagy inhibitor 3-methyladenine (3-MA) suppressed the growth of leukemia cell lines HuT78, Jurkat, MT-1, and MT-4. CuD-induced cell death was enhanced by 3-MA in Jurkat cells, but inhibited in MT-4 cells. Western blotting results revealed cleavage of poly(ADP ribose) polymerase (PARP), supporting CuD-induced cell death; 3-MA enhanced CuD-Z36-induced PARP cleavage. Taken together, our results indicate that autophagy negatively regulates chemical-induced cell death of leukemia cells, and that controlling autophagy could be beneficial in the development of more effective chemotherapies against leukemia.

  19. Myeloid cell leukemia-1 is a key molecular target for mithramycin A-induced apoptosis in androgen-independent prostate cancer cells and a tumor xenograft animal model.

    Science.gov (United States)

    Choi, Eun-Sun; Jung, Ji-Youn; Lee, Jin-Seok; Park, Jong-Hwan; Cho, Nam-Pyo; Cho, Sung-Dae

    2013-01-01

    Mithramycin A (Mith) is a natural polyketide that has been used in multiple areas of research including apoptosis of various cancer cells. Here, we examined the critical role of Mith in apoptosis and its molecular mechanism in DU145 and PC3 prostate cancer cells and tumor xenografts. Mith decreased cell growth and induced apoptosis in DU145 and PC-3 cells. Myeloid cell leukemia-1 (Mcl-1) was over-expressed in both cell lines compared to RWPE1 cells. Mith inhibited Mcl-1 protein expression in both cells, but only altered Mcl-1 mRNA levels in PC-3 cells. We also found that Mith reduced Mcl-1 protein levels through both proteasome-dependent protein degradation and the inhibition of protein synthesis in DU145 cells. Studies using siRNA confirmed that the knockdown of Mcl-1 induced apoptosis. Mith significantly suppressed TPA-induced neoplastic cell transformation through the down-regulation of the Mcl-1 protein in JB6 cells, and suppressed the transforming activity of both cell types. Mith also inhibited tumor growth and Mcl-1 levels, in addition to inducing apoptosis, in athymic nude mice bearing DU145 cell xenografts without affecting five normal organs. Therefore, Mith inhibits cell growth and induces apoptosis by suppressing Mcl-1 in both prostate cancer cells and xenograft tumors, and thus is a potent anticancer drug candidate for prostate cancer.

  20. ROS-induced autophagy in cancer cells assists in evasion from determinants of immunogenic cell death

    NARCIS (Netherlands)

    Garg, A.D.; Dudek, A.M.D.; Ferreira, G.B.; Verfaillie, T.; Vandenabeele, P.; Krysko, D.V.; Mathieu, C.; Agostinis, P.

    2013-01-01

    Calreticulin surface exposure (ecto-CALR), ATP secretion, maturation of dendritic cells (DCs) and stimulation of T cells are prerequisites for anticancer therapy-induced immunogenic cell death (ICD). Recent evidence suggests that chemotherapy-induced autophagy may positively regulate ICD by favoring

  1. Apoptin induces apoptosis in human transformed and malignant cells but not in normal cells

    NARCIS (Netherlands)

    Dane-Oorschot, A.A.A.M. van; Fischer, D.F.; Grimbergen, J.M.; Klein, B.; Zhuang, S.M.; Falkenburg, J.H.F.; Backendorf, C.; Quax, P.H.A.; Eb, A.J. van der; Noteborn, M.H.M.

    1997-01-01

    The chicken anemia virus protein apoptin induces a p53-independent, Bcl- 2-insensitive type of apoptosis in various human tumor cells. Here, we show that, in vitro, apoptin fails to induce programmed cell death in normal lymphoid, dermal, epidermal, endothelial, and smooth-muscle cells. However, whe

  2. Crizotinib induces PUMA-dependent apoptosis in colon cancer cells.

    Science.gov (United States)

    Zheng, Xingnan; He, Kan; Zhang, Lin; Yu, Jian

    2013-05-01

    Oncogenic alterations in MET or anaplastic lymphoma kinase (ALK) have been identified in a variety of human cancers. Crizotinib (PF02341066) is a dual MET and ALK inhibitor and approved for the treatment of a subset of non-small cell lung carcinoma and in clinical development for other malignancies. Crizotinib can induce apoptosis in cancer cells, whereas the underlying mechanisms are not well understood. In this study, we found that crizotinib induces apoptosis in colon cancer cells through the BH3-only protein PUMA. In cells with wild-type p53, crizotinib induces rapid induction of PUMA and Bim accompanied by p53 stabilization and DNA damage response. The induction of PUMA and Bim is mediated largely by p53, and deficiency in PUMA or p53, but not Bim, blocks crizotinib-induced apoptosis. Interestingly, MET knockdown led to selective induction of PUMA, but not Bim or p53. Crizotinib also induced PUMA-dependent apoptosis in p53-deficient colon cancer cells and synergized with gefitinib or sorafenib to induce marked apoptosis via PUMA in colon cancer cells. Furthermore, PUMA deficiency suppressed apoptosis and therapeutic responses to crizotinib in xenograft models. These results establish a critical role of PUMA in mediating apoptotic responses of colon cancer cells to crizotinib and suggest that mechanisms of oncogenic addiction to MET/ALK-mediated survival may be cell type-specific. These findings have important implications for future clinical development of crizotinib.

  3. Characterization and comparison of osteoblasts derived from mouse embryonic stem cells and induced pluripotent stem cells

    NARCIS (Netherlands)

    Ma, Ming-San; Kannan, Vishnu; de Vries, Anneriek E; Czepiel, Marcin; Wesseling, Evelyn M; Balasubramaniyan, Veerakumar; Kuijer, Roelof; Vissink, Arjan; Copray, Sjef C V M; Raghoebar, Gerry M

    2016-01-01

    New developments in stem cell biology offer alternatives for the reconstruction of critical-sized bone defects. One of these developments is the use of induced pluripotent stem (iPS) cells. These stem cells are similar to embryonic stem (ES) cells, but can be generated from adult somatic cells and t

  4. Dendritic cells fused with different pancreatic carcinoma cells induce different T-cell responses

    Directory of Open Access Journals (Sweden)

    Andoh Y

    2013-01-01

    Full Text Available Yoshiaki Andoh,1,2 Naohiko Makino,2 Mitsunori Yamakawa11Department of Pathological Diagnostics, 2Department of Gastroenterology, Yamagata University School of Medicine, Yamagata, JapanBackground: It is unclear whether there are any differences in the induction of cytotoxic T lymphocytes (CTL and CD4+CD25high regulatory T-cells (Tregs among dendritic cells (DCs fused with different pancreatic carcinomas. The aim of this study was to compare the ability to induce cytotoxicity by human DCs fused with different human pancreatic carcinoma cell lines and to elucidate the causes of variable cytotoxicity among cell lines.Methods: Monocyte-derived DCs, which were generated from peripheral blood mononuclear cells (PBMCs, were fused with carcinoma cells such as Panc-1, KP-1NL, QGP-1, and KP-3L. The induction of CTL and Tregs, and cytokine profile of PBMCs stimulated by fused DCs were evaluated.Results: The cytotoxicity against tumor targets induced by PBMCs cocultured with DCs fused with QGP-1 (DC/QGP-1 was very low, even though PBMCs cocultured with DCs fused with other cell lines induced significant cytotoxicity against the respective tumor target. The factors causing this low cytotoxicity were subsequently investigated. DC/QGP-1 induced a significant expansion of Tregs in cocultured PBMCs compared with DC/KP-3L. The level of interleukin-10 secreted in the supernatants of PBMCs cocultured with DC/QGP-1 was increased significantly compared with that in DC/KP-3L. Downregulation of major histocompatibility complex class I expression and increased secretion of vascular endothelial growth factor were observed with QGP-1, as well as in the other cell lines.Conclusion: The present study demonstrated that the cytotoxicity induced by DCs fused with pancreatic cancer cell lines was different between each cell line, and that the reduced cytotoxicity of DC/QGP-1 might be related to the increased secretion of interleukin-10 and the extensive induction of Tregs

  5. Type I collagen gel protects murine fibrosarcoma L929 cells from TNFα-induced cell death

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Hong-Ju; He, Wen-Qi; Chen, Ling; Liu, Wei-Wei; Xu, Qian; Xia, Ming-Yu; Hayashi, Toshihiko [China-Japan Research Institute of Medical and Pharmaceutical Sciences, Shenyang Pharmaceutical University, Shenyang 110016 (China); Fujisaki, Hitomi; Hattori, Shunji [Nippi Research Institute of Biomatrix, Toride, Ibaraki 302-0017 (Japan); Tashiro, Shin-ichi [Institute for Clinical and Biomedical Sciences, Kyoto 603-8072 (Japan); Onodera, Satoshi [Department of Clinical and Pharmaceutical Sciences, Showa Pharmaceutical University, Tokyo 194-8543 (Japan); Ikejima, Takashi, E-mail: ikejimat@vip.sina.com [China-Japan Research Institute of Medical and Pharmaceutical Sciences, Shenyang Pharmaceutical University, Shenyang 110016 (China)

    2015-02-20

    Murine fibrosarcoma L929 cells have been used to test efficacy of proinflammatory cytokine TNFα. In the present study, we reported on protective effect of type I collagen gel used as L929 cell culture. L929 cell grew and proliferated well on collagen gel. However, the L929 cells exhibited cobblestone-like morphology which was much different from the spread fusiform shape when cultured on conventional cell dishes as well as the cells tended to aggregate. On conventional cell culture dishes, the cells treated with TNFα became round in shape and eventually died in a necroptotic manner. The cells cultured on collagen gel, however, were completely unaffected. TNFα treatment was reported to induce autophagy in L929 cells on the plastic dish, and therefore we investigated the effect of collagen gel on induction of autophagy. The results indicated that autophagy induced by TNFα treatment was much reduced when the cells were cultured on collagen gel. In conclusion, type I collagen gel protected L929 cell from TNFα-induced cell death. - Highlights: • Collagen gel culture changed the morphology of L929 cells. • L929 cell cultured on collagen gel were resistant to TNFα-induced cell death. • Collagen gel culture inhibited TNFα-induced autophagy in L929 cells.

  6. Inhibitory effects of isoproterenol on PAF-induced endothelial cell permeability and morphological changes

    Institute of Scientific and Technical Information of China (English)

    丁自强; 李少华; 吴中立

    1996-01-01

    Using a model to study vascular permeability under hydrostatically perfused bovine pulmonary artery endothelial cell (EC) monolayers and a software to automatically analyse cell morphological parameters in a computer image workstation, the effects of isoproterenol (IPN) on platelet-activating factor (PAF)-induced changes in EC monolayer permeability and cell morphological parameters were studied. Albumin has the fortifying effect on endothelial barrier function. After treatment of EC monolayer with 10-8mol/L PAF, trans-monolayer permeability increased, cell surface area decreased, and intercellular space enlarged. As pretreatment with 10-4mol/L IPN, PAF-induced EC permeability increment and morphological changes were blocked. The results suggest that EC contraction and intercellular gap expansion are important mechanisms for PAF-induced high vascular permeability. IPN inhibits the effects of PAF via stabilization of EC morphology and prevention of intercellular gap formation.

  7. Brucella abortus-infected B cells induce osteoclastogenesis.

    Science.gov (United States)

    Pesce Viglietti, Ayelén Ivana; Arriola Benitez, Paula Constanza; Giambartolomei, Guillermo Hernán; Delpino, María Victoria

    2016-09-01

    Brucella abortus is an intracellular bacterium that establishes lifelong infections in livestock and humans although the mechanisms of its chronicity are poorly understood. Activated B cells have long lifespan and B. abortus infection activates B cells. Our results indicate that the direct infection of B cells with B. abortus induced matrix metalloproteinase-9 (MMP-9), receptor activator for NF κB ligand (RANKL), tumor necrosis factor (TNF)-α and interleukin (IL)-6 secretion. In addition, supernatants from B. abortus-infected B cells induced bone marrow-derived monocytes to undergo osteoclastogenesis. Using osteoprotegerin, RANKL's decoy receptor, we determined that RANKL is involved in osteoclastogenesis induced by supernatants from B. abortus-infected B cells. The results presented here shed light on how the interactions of B. abortus with B cells may have a role in the pathogenesis of brucellar osteoarticular disease.

  8. Generation of induced pluripotent stem cells from human blood.

    Science.gov (United States)

    Loh, Yuin-Han; Agarwal, Suneet; Park, In-Hyun; Urbach, Achia; Huo, Hongguang; Heffner, Garrett C; Kim, Kitai; Miller, Justine D; Ng, Kitwa; Daley, George Q

    2009-05-28

    Human dermal fibroblasts obtained by skin biopsy can be reprogrammed directly to pluripotency by the ectopic expression of defined transcription factors. Here, we describe the derivation of induced pluripotent stem cells from CD34+ mobilized human peripheral blood cells using retroviral transduction of OCT4/SOX2/KLF4/MYC. Blood-derived human induced pluripotent stem cells are indistinguishable from human embryonic stem cells with respect to morphology, expression of surface antigens, and pluripotency-associated transcription factors, DNA methylation status at pluripotent cell-specific genes, and the capacity to differentiate in vitro and in teratomas. The ability to reprogram cells from human blood will allow the generation of patient-specific stem cells for diseases in which the disease-causing somatic mutations are restricted to cells of the hematopoietic lineage.

  9. Induction of morphological changes in death-induced cancer cells monitored by holographic microscopy.

    Science.gov (United States)

    El-Schich, Zahra; Mölder, Anna; Tassidis, Helena; Härkönen, Pirkko; Falck Miniotis, Maria; Gjörloff Wingren, Anette

    2015-03-01

    We are using the label-free technique of holographic microscopy to analyze cellular parameters including cell number, confluence, cellular volume and area directly in the cell culture environment. We show that death-induced cells can be distinguished from untreated counterparts by the use of holographic microscopy, and we demonstrate its capability for cell death assessment. Morphological analysis of two representative cell lines (L929 and DU145) was performed in the culture flasks without any prior cell detachment. The two cell lines were treated with the anti-tumour agent etoposide for 1-3days. Measurements by holographic microscopy showed significant differences in average cell number, confluence, volume and area when comparing etoposide-treated with untreated cells. The cell volume of the treated cell lines was initially increased at early time-points. By time, cells decreased in volume, especially when treated with high doses of etoposide. In conclusion, we have shown that holographic microscopy allows label-free and completely non-invasive morphological measurements of cell growth, viability and death. Future applications could include real-time monitoring of these holographic microscopy parameters in cells in response to clinically relevant compounds.

  10. Changes of ecological conditions induced by rock tunneling in Laoshan Mountain area

    Institute of Scientific and Technical Information of China (English)

    Xiaozhao LI; Xiaobao ZHAO; Zhongsheng WANG

    2008-01-01

    Through field investigation, this paper exam-ined the changes of ecological conditions induced by tun-nel construction in Laoshan Mountain area, Nanjing, Jiangsu Province, P. R. China. The effects of habitat frag-mentation and edge effect are examined and discussed. It is found that the environmental factors and vegetation situation have been influenced by the tunneling activity, and the disturbed area is approaching the sampling patch centre. The changed ecological conditions are beneficial for the settlement and growth of some herb and shrub species, and are unfavorable for the existence and growth of saplings, especially for the predominant species (e.g., robur) in this area. If the time of habitat fragmentation is long enough and there is no supplement from external areas, some vegetation species in the engineering influ-encing area will deteriorate, or even diminish in the future. The results can be used as a reference for the long-term ecological study in this area.

  11. Cell therapy using induced pluripotent stem cells or somatic stem cells: this is the question.

    Science.gov (United States)

    Somoza, Rodrigo A; Rubio, Francisco J

    2012-05-01

    A lot of effort has been developed to bypass the use of embryonic stem cells (ES) in human therapies, because of several concerns and ethical issues. Some unsolved problems of using stem cells for human therapies, excluding the human embryonic origin, are: how to regulate cell plasticity and proliferation, immunological compatibility, potential adverse side-effects when stem cells are systemically administrated, and the in vivo signals to rule out a specific cell fate after transplantation. Currently, it is known that almost all tissues of an adult organism have somatic stem cells (SSC). Whereas ES are primary involved in the genesis of new tissues and organs, SSC are involved in regeneration processes, immuno-regulatory and homeostasis mechanisms. Although the differentiating potential of ES is higher than SSC, several studies suggest that some types of SSC, such as mesenchymal stem cells (MSC), can be induced epigenetically to differentiate into tissue-specific cells of different lineages. This unexpected pluripotency and the variety of sources that they come from, can make MSC-like cells suitable for the treatment of diverse pathologies and injuries. New hopes for cell therapy came from somatic/mature cells and the discovery that could be reprogrammed to a pluripotent stage similar to ES, thus generating induced pluripotent stem cells (iPS). For this, it is necessary to overexpress four main reprogramming factors, Sox2, Oct4, Klf4 and c-Myc. The aim of this review is to analyze the potential and requirements of cellular based tools in human therapy strategies, focusing on the advantage of using MSC over iPS.

  12. The Alpha-Melanocyte Stimulating Hormone Induces Conversion of Effector T Cells into Treg Cells

    Directory of Open Access Journals (Sweden)

    Andrew W. Taylor

    2011-01-01

    Full Text Available The neuropeptide alpha-melanocyte stimulating hormone (α-MSH has an important role in modulating immunity and homeostasis. The production of IFN-γ by effector T cells is suppressed by α-MSH, while TGF-β production is promoted in the same cells. Such α-MSH-treated T cells have immune regulatory activity and suppress hypersensitivity, autoimmune diseases, and graft rejection. Previous characterizations of the α-MSH-induced Treg cells showed that the cells are CD4+ T cells expressing the same levels of CD25 as effector T cells. Therefore, we further analyzed the α-MSH-induced Treg cells for expression of effector and regulatory T-cell markers. Also, we examined the potential for α-MSH-induced Treg cells to be from the effector T-cell population. We found that the α-MSH-induced Treg cells are CD25+  CD4+ T cells that share similar surface markers as effector T cells, except that they express on their surface LAP. Also, the α-MSH treatment augments FoxP3 message in the effector T cells, and α-MSH induction of regulatory activity was limited to the effector CD25+ T-cell population. Therefore, α-MSH converts effector T cells into Treg cells, which suppress immunity targeting specific antigens and tissues.

  13. Isogambogenic acid induces apoptosis-independent autophagic cell death in human non-small-cell lung carcinoma cells.

    Science.gov (United States)

    Yang, Jianhong; Zhou, Yongzhao; Cheng, Xia; Fan, Yi; He, Shichao; Li, Shucai; Ye, Haoyu; Xie, Caifeng; Wu, Wenshuang; Li, Chunyan; Pei, Heying; Li, Luyuan; Wei, Zhe; Peng, Aihua; Wei, Yuquan; Li, Weimin; Chen, Lijuan

    2015-01-09

    To overcome drug resistance caused by apoptosis deficiency in patients with non-small cell lung carcinoma (NSCLC), there is a need to identify other means of triggering apoptosis-independent cancer cell death. We are the first to report that isogambogenic acid (iso-GNA) can induce apoptosis-independent autophagic cell death in human NSCLC cells. Several features of the iso-GNA-treated NSCLC cells indicated that iso-GNA induced autophagic cell death. First, there was no evidence of apoptosis or cleaved caspase 3 accumulation and activation. Second, iso-GNA treatment induced the formation of autophagic vacuoles, increased LC3 conversion, caused the appearance of autophagosomes and increased the expression of autophagy-related proteins. These findings provide evidence that iso-GNA induces autophagy in NSCLC cells. Third, iso-GNA-induced cell death was inhibited by autophagic inhibitors or by selective ablation of Atg7 and Beclin 1 genes. Furthermore, the mTOR inhibitor rapamycin increased iso-GNA-induced cell death by enhancing autophagy. Finally, a xenograft model provided additional evidence that iso-GNA exhibited anticancer effect through inducing autophagy-dependent cell death in NSCLC cells. Taken together, our results demonstrated that iso-GNA exhibited an anticancer effect by inducing autophagy-dependent cell death in NSCLC cells, which may be an effective chemotherapeutic agent that can be used against NSCLC in a clinical setting.

  14. Islet-cell dysfunction induced by glucocorticoid treatment

    DEFF Research Database (Denmark)

    van Raalte, Daniël H; Kwa, Kelly A A; van Genugten, Renate E

    2013-01-01

    Glucocorticoids impair glucose tolerance by inducing insulin resistance. We investigated the dose-dependent effects of glucocorticoid treatment on islet-cell function in healthy males and studied the role of the autonomic nervous system....

  15. Aspartame-induced apoptosis in PC12 cells.

    Science.gov (United States)

    Horio, Yukari; Sun, Yongkun; Liu, Chuang; Saito, Takeshi; Kurasaki, Masaaki

    2014-01-01

    Aspartame is an artificial sweetner added to many low-calorie foods. The safety of aspartame remains controversial even though there are many studies on its risks. In this study, to understand the physiological effects of trace amounts of artificial sweetners on cells, the effects of aspartame on apoptosis were investigated using a PC12 cell system. In addition, the mechanism of apoptosis induced by aspartame in PC12 cells and effects on apoptotic factors such as cytochrome c, apoptosis-inducing factor, and caspase family proteins were studied by Western blotting and RT-PCR. Aspartame-induced apoptosis in PC12 cells in a dose-dependent manner. In addition, aspartame exposure increased the expressions of caspases 8 and 9, and cytochrome c. These results indicate that aspartame induces apoptosis mainly via mitochondrial pathway involved in apoptosis due to oxigen toxicity.

  16. Lateral inhibition-induced pattern formation controlled by the size and geometry of the cell.

    Science.gov (United States)

    Seirin Lee, Sungrim

    2016-09-01

    Pattern formation in development biology is one of the fundamental processes by which cells change their functions. It is based on the communication of cells via intra- and intercellular dynamics of biochemicals. Thus, the cell is directly involved in biochemical interactions. However, many theoretical approaches describing biochemical pattern formation have usually neglected the cell's role or have simplified the subcellular process without considering cellular aspects despite the cell being the environment where biochemicals interact. On the other hand, recent experimental observations suggest that a change in the physical conditions of cell-to-cell contact can result in a change in cell fate and tissue patterning in a lateral inhibition system. Here we develop a mathematical model by which biochemical dynamics can be directly observed with explicitly expressed cell structure and geometry in higher dimensions, and reconsider pattern formation by lateral inhibition of the Notch-Delta signaling pathway. We explore how the physical characteristic of cell, such as cell geometry or size, influences the biochemical pattern formation in a multi-cellular system. Our results suggest that a property based on cell geometry can be a novel mechanism for symmetry breaking inducing cell asymmetry. We show that cell volume can critically influence cell fate determination and pattern formation at the tissue level, and the surface area of the cell-to-cell contact can directly affect the spatial range of patterning.

  17. Activation of intracellular angiotensin AT2 receptors induces rapid cell death in human uterine leiomyosarcoma cells

    DEFF Research Database (Denmark)

    Zhao, Yi; Lützen, Ulf; Fritsch, Jürgen;

    2015-01-01

    densities in mitochondria. Activation of the cell membrane AT2 receptors by a concomitant treatment with angiotensin II and the AT1 receptor antagonist, losartan, induces apoptosis but does not affect the rate of cell death. We demonstrate for the first time that the high-affinity, non-peptide AT2 receptor...... of apoptosis and cell death in cultured human uterine leiomyosarcoma (SK-UT-1) cells and control human uterine smooth muscle cells (HutSMC). The intracellular levels of the AT2 receptor are low in proliferating SK-UT-1 cells but the receptor is substantially up-regulated in quiescent SK-UT-1 cells with high...... agonist, Compound 21 (C21) penetrates the cell membrane of quiescent SK-UT-1 cells, activates intracellular AT2 receptors and induces rapid cell death; approximately 70% of cells died within 24 h. The cells, which escaped from the cell death, displayed activation of the mitochondrial apoptotic pathway, i...

  18. Suppression of T cell-induced osteoclast formation

    Energy Technology Data Exchange (ETDEWEB)

    Karieb, Sahar; Fox, Simon W., E-mail: Simon.fox@plymouth.ac.uk

    2013-07-12

    Highlights: •Genistein and coumestrol prevent activated T cell induced osteoclast formation. •Anti-TNF neutralising antibodies prevent the pro-osteoclastic effect of activated T cells. •Phytoestrogens inhibit T cell derived TNF alpha and inflammatory cytokine production. •Phytoestrogens have a broader range of anti-osteoclastic actions than other anti-resorptives. -- Abstract: Inhibition of T cell derived cytokine production could help suppress osteoclast differentiation in inflammatory skeletal disorders. Bisphosphonates are typically prescribed to prevent inflammatory bone loss but are not tolerated by all patients and are associated with an increased risk of osteonecrosis of the jaw. In light of this other anti-resorptives such as phytoestrogens are being considered. However the effect of phytoestrogens on T cell-induced osteoclast formation is unclear. The effect of genistein and coumestrol on activated T cell-induced osteoclastogenesis and cytokine production was therefore examined. Concentrations of genistein and coumestrol (10{sup −7} M) previously shown to directly inhibit osteoclast formation also suppressed the formation of TRAP positive osteoclast induced by con A activated T cells, which was dependent on inhibition of T cell derived TNF-α. While both reduced osteoclast formation their mechanism of action differed. The anti-osteoclastic effect of coumestrol was associated with a dual effect on con A induced T cell proliferation and activation; 10{sup −7} M coumestrol significantly reducing T cell number (0.36) and TNF-α (0.47), IL-1β (0.23) and IL-6 (0.35) expression, whereas genistein (10{sup −7} M) had no effect on T cell number but a more pronounced effect on T cell differentiation reducing expression of TNF-α (0.49), IL-1β (0.52), IL-6 (0.71) and RANKL (0.71). Phytoestrogens therefore prevent the pro-osteoclastic action of T cells suggesting they may have a role in the control of inflammatory bone loss.

  19. [Induced-division of neurons derived from neural stem cells].

    Science.gov (United States)

    Lin, Qiu-Xia; Que, Hai-Ping; Lu, Shuang-Hong; Liu, Shao-Jun

    2004-04-25

    In order to explore if mature neurons derived from neural stem cells have the potentiality to divide, we utilized the chemical digestion method to disperse the adult rat brain tissue into single cells, and culture them in serum-free medium. After being cultured for about eight days in vitro, the neural stem cells were induced to differentiate into neurons. The neurons were further induced to divide. Utilizing the method of serial photograph and NF-160 immunocytochemistry, the processes of division of some neurons were recorded. At the same time, PCNA+NF-160 (or Chat, GABA, GAD) double label were used to investigate if the dividing-neurons were mature ones. After the neural stem cells were induced to differentiate in vitro for eight days, they possessed the shape and character of mature neurons. The differentiated neuron had a big nucleus and one or two distinct nucleolus in the nuclear. Within the perikaryon,there were a large amount of dense and Nissl body-like structure. Several long processes emerged from various locations of the cell body. Then, EGF and bFGF were added into the medium to induce division. After two days of induced-division, neuron-like cells were observed to divide; moreover, the number of neuron-like cells in the region increased continually. Immunocytochemistry demonstrated these cells were NF-160-positive. Serial photographs of dividing-process of neuron-like cells were obtained and their daughter cells were also NF-160-positive. After PCNA+NF-160 (or Chat, GABA, GAD) double label, some cells showed brown cell plasma and black nucleus. The above-mentioned results indicate that neurons, which were previously thought to be end-differentiated, can be re-called into cell cycle under appropriate conditions. Mature neurons still have the potential to divide, proliferate and self-renew.

  20. Generation of human induced pluripotent stem cells from dermal fibroblasts.

    Science.gov (United States)

    Lowry, W E; Richter, L; Yachechko, R; Pyle, A D; Tchieu, J; Sridharan, R; Clark, A T; Plath, K

    2008-02-26

    The generation of patient-specific pluripotent stem cells has the potential to accelerate the implementation of stem cells for clinical treatment of degenerative diseases. Technologies including somatic cell nuclear transfer and cell fusion might generate such cells but are hindered by issues that might prevent them from being used clinically. Here, we describe methods to use dermal fibroblasts easily obtained from an individual human to generate human induced pluripotent stem (iPS) cells by ectopic expression of the defined transcription factors KLF4, OCT4, SOX2, and C-MYC. The resultant cell lines are morphologically indistinguishable from human embryonic stem cells (HESC) generated from the inner cell mass of a human preimplantation embryo. Consistent with these observations, human iPS cells share a nearly identical gene-expression profile with two established HESC lines. Importantly, DNA fingerprinting indicates that the human iPS cells were derived from the donor material and are not a result of contamination. Karyotypic analyses demonstrate that reprogramming of human cells by defined factors does not induce, or require, chromosomal abnormalities. Finally, we provide evidence that human iPS cells can be induced to differentiate along lineages representative of the three embryonic germ layers indicating the pluripotency of these cells. Our findings are an important step toward manipulating somatic human cells to generate an unlimited supply of patient-specific pluripotent stem cells. In the future, the use of defined factors to change cell fate may be the key to routine nuclear reprogramming of human somatic cells.

  1. Supporting Cells-a New Area in Cochlear Physiology Study

    Institute of Scientific and Technical Information of China (English)

    ZHAO Li-dong; LIU Jun; HU Yin-yan; SUN Jian-he; YANG Shi-ming

    2008-01-01

    For many years, studies about the cochlea have been mainly focused on sensory cells, i.e. the inner hair cell (IHC) and outer hair cell (OHC), and the neuron system. Supporting cells, such as Hensen's cells and Deiters' cells are less studied. Their physiological functions and other characteris-tics are not well documented. Nowadays, supporting cells are a new world attracting to scientists" inter-ests. The scope of this review is to detail the biological properties of the supporting cells, mainly Hensen's cells and Deiters' cells in the cochlea. Studies on this subject will be helpful in understanding physiology of the cochlea, and hopefully provide new approaches in treating diseases of inner ear.

  2. Induced pluripotent stem cells: origins, applications, and future perspectives.

    Science.gov (United States)

    Zhao, Jing; Jiang, Wen-jie; Sun, Chen; Hou, Cong-zhe; Yang, Xiao-Mei; Gao, Jian-gang

    2013-12-01

    Embryonic stem (ES) cells are widely used for different purposes, including gene targeting, cell therapy, tissue repair, organ regeneration, and so on. However, studies and applications of ES cells are hindered by ethical issues regarding cell sources. To circumvent ethical disputes, great efforts have been taken to generate ES cell-like cells, which are not derived from the inner cell mass of blastocyst-stage embryos. In 2006, Yamanaka et al. first reprogrammed mouse embryonic fibroblasts into ES cell-like cells called induced pluripotent stem (iPS) cells. About one year later, Yamanaka et al. and Thomson et al. independently reprogrammed human somatic cells into iPS cells. Since the first generation of iPS cells, they have now been derived from quite a few different kinds of cell types. In particular, the use of peripheral blood facilitates research on iPS cells because of safety, easy availability, and plenty of cell sources. Now iPS cells have been used for cell therapy, disease modeling, and drug discovery. In this review, we describe the generations, applications, potential issues, and future perspectives of iPS cells.

  3. The physics of photon induced degradation of perovskite solar cells

    OpenAIRE

    Pranav H. Joshi; Liang Zhang; Istiaque M. Hossain; Hisham A. Abbas; Ranjith Kottokkaran; Satyapal P. Nehra; Mahendra Dhaka; Max Noack; Vikram L. Dalal

    2016-01-01

    Lead-trihalide perovskite solar cells are an important photovoltaic technology. We investigate the effect of light induced degradation on perovskite solar cells. During exposure, the open-circuit voltage (Voc) of the device increases, whereas the short-circuit current (Isc) shows a decrease. The degradation can be completely recovered using thermal annealing in dark. We develop a model based on light induced generation of ions and migration of these ions inside the material to explain the cha...

  4. MiR-122 Induces Radiosensitization in Non-Small Cell Lung Cancer Cell Line

    Directory of Open Access Journals (Sweden)

    Debin Ma

    2015-09-01

    Full Text Available MiR-122 is a novel tumor suppresser and its expression induces cell cycle arrest, or apoptosis, and inhibits cell proliferation in multiple cancer cells, including non-small cell lung cancer (NSCLC cells. Radioresistance of cancer cell leads to the major drawback of radiotherapy for NSCLC and the induction of radiosensitization could be a useful strategy to fix this problem. The present work investigates the function of miR-122 in inducing radiosensitization in A549 cell, a type of NSCLC cells. MiR-122 induces the radiosensitization of A549 cells. MiR-122 also boosts the inhibitory activity of ionizing radiation (IR on cancer cell anchor-independent growth and invasion. Moreover, miR-122 reduced the expression of its targeted genes related to tumor-survival or cellular stress response. These results indicate that miR-122 would be a novel strategy for NSCLC radiation-therapy.

  5. A study of earthquakes induced by water injection in the Changning salt mine area, SW China

    Science.gov (United States)

    Sun, Xiaolong; Yang, Pengtao; Zhang, Zhiwei

    2017-04-01

    The features of earthquakes induced by water injection in the Changning salt mine area of China were analyzed using the pore pressure diffusion method. The relationships between maximum magnitude, cumulative seismic moment, and cumulative water loss volume were investigated. Results show that increased seismic activities near the Changning salt mine in recent years are closely related to water injection during salt mining. High-pressure water injection over a long period of time caused water to diffuse into rock cracks, which increased pore pressure on faults and induced ruptures. Injection-induced earthquakes were located below the injection sites, mainly aligned NW-SE, with most occurring southeast of the mine area. Such a distribution indicates that seismic activities were affected by anticline structures in the Changning area. Based on pore pressure diffusion considerations, the diffusion coefficient was estimated to be ∼0.15 m2/s, with a slightly lower value west of the injection site than to the east. A semi-logarithmic linear relationship was found between cumulative seismic moment and cumulative water loss volume, while maximum magnitude increased with increasing volume of cumulative water loss. This study may provide reference material for analysis of injection-induced earthquakes and evaluation of the danger of earthquakes induced by water injection.

  6. Cell cycle-arrested tumor cells exhibit increased sensitivity towards TRAIL-induced apoptosis

    OpenAIRE

    Ehrhardt, H.; Wachter, F; Grunert, M.; Jeremias, I

    2013-01-01

    Resting tumor cells represent a huge challenge during anticancer therapy due to their increased treatment resistance. TNF-related apoptosis-inducing ligand (TRAIL) is a putative future anticancer drug, currently in phases I and II clinical studies. We recently showed that TRAIL is able to target leukemia stem cell surrogates. Here, we tested the ability of TRAIL to target cell cycle-arrested tumor cells. Cell cycle arrest was induced in tumor cell lines and xenografted tumor cells in G0, G1 o...

  7. Inducible expression of endomorphins in murine dendritic cells.

    Science.gov (United States)

    Yang, Xiaohuai; Xia, Hui; Chen, Yong; Liu, Xiaofen; Zhou, Cheng; Gao, Qin; Li, Zhenghong

    2012-12-15

    Bone marrow precursor cells were extracted from C57BL/6J mice aged 7-8 weeks, and dendritic cells were purified using anti-CD11c (a specific marker for dendritic cells) antibody-coated magnetic beads. Immunofluorescence staining revealed that the expression levels of endomorphin-1 and endomorphin-2 were upregulated in dendritic cells activated by lipopolysaccharide. An enzyme immunoassay showed that lipopolysaccharide and other Toll-like receptor ligands promoted the secretion of endomorphin-1 and endomorphin-2 from activated dendritic cells. [(3)H]-thymidine incorporation demonstrated that endomorphin-1 and endomorphin-2 both inhibited the proliferation of T lymphocyte induced by activated dendritic cells. Furthermore, this immunosuppressive effect was blocked by CTOP, a specific antagonist of µ-opioid receptors. Our experimental findings indicate that activated dendritic cells can induce the expression and secretion of endomorphins, and that endomorphins suppress T lymphocyte proliferation through activation of µ-opioid receptors.

  8. Inducible expression of endomorphins in murine dendritic cells

    Institute of Scientific and Technical Information of China (English)

    Xiaohuai Yang; Hui Xia; Yong Chen; Xiaofen Liu; Cheng Zhou; Qin Gao; Zhenghong Li

    2012-01-01

    Bone marrow precursor cells were extracted from C57BL/6J mice aged 7–8 weeks, and dendritic cells were purified using anti-CD11c (a specific marker for dendritic cells) antibody-coated magnetic beads. Immunofluorescence staining revealed that the expression levels of endomorphin-1 and endomorphin-2 were upregulated in dendritic cells activated by lipopolysaccharide. An enzyme immunoassay showed that lipopolysaccharide and other Toll-like receptor ligands promoted the secretion of endomorphin-1 and endomorphin-2 from activated dendritic cells. [3H]-thymidine incorporation demonstrated that endomorphin-1 and endomorphin-2 both inhibited the proliferation of T lymphocyte induced by activated dendritic cells. Furthermore, this immunosuppressive effect was blocked by CTOP, a specific antagonist of μ-opioid receptors. Our experimental findings indicate that activated dendritic cells can induce the expression and secretion of endomorphins, and that endomorphins suppress T lymphocyte proliferation through activation of μ-opioid receptors.

  9. High dose of ascorbic acid induces cell death in mesothelioma cells.

    Science.gov (United States)

    Takemura, Yukitoshi; Satoh, Motohiko; Satoh, Kiyotoshi; Hamada, Hironobu; Sekido, Yoshitaka; Kubota, Shunichiro

    2010-04-02

    Malignant mesothelioma is an asbestos-related fatal disease with no effective cure. Recently, high dose of ascorbate in cancer treatment has been reexamined. We studied whether high dose of ascorbic acid induced cell death of four human mesothelioma cell lines. High dose of ascorbic acid induced cell death of all mesothelioma cell lines in a dose-dependent manner. We further clarified the cell killing mechanism that ascorbic acid induced reactive oxygen species and impaired mitochondrial membrane potential. In vivo experiment, intravenous administration of ascorbic acid significantly decreased the growth rate of mesothelioma tumor inoculated in mice. These data suggest that ascorbic acid may have benefits for patients with mesothelioma.

  10. Turkish propolis supresses MCF-7 cell death induced by homocysteine.

    Science.gov (United States)

    Tartik, Musa; Darendelioglu, Ekrem; Aykutoglu, Gurkan; Baydas, Giyasettin

    2016-08-01

    Elevated plasma homocysteine (Hcy) level is a most important risk factor for various vascular diseases including coronary, cerebral and peripheral arterial and venous thrombosis. Propolis is produced by honeybee from various oils, pollens and wax materials. Therefore, it has various biological properties including antioxidant, antitumor and antimicrobial activities. This study investigated the effects of propolis and Hcy on apoptosis in cancer cells. According to our findings, Hcy induced apoptosis in human breast adenocarcinoma (MCF-7) cells by regulating numerous genes and proteins involved in the apoptotic signal transduction pathway. In contrast, treatment with propolis inhibited caspase- 3 and -9 induced by Hcy in MCF-7 cells. It can be concluded that Hcy may augment the activity of anticancer agents that induce excessive reactive oxygen species (ROS) generation and apoptosis in their target cells. In contrast to the previous studies herein we found that propolis in low doses protected cancer cells inhibiting cellular apoptosis mediated by intracellular ROS-dependent mitochondrial pathway.

  11. Human Soluble TRAIL Protein Inducing Apoptosis in Osteosarcoma Cell

    Institute of Scientific and Technical Information of China (English)

    ZHU Shaobo; YU Aixi; ZHANG Zhongning; WU Gang

    2007-01-01

    This study is to examine the effect of human recombinant soluble TRAIL (TNF-related apoptosis-inducing ligand) protein inducing apoptosis in MG-63 human osteosarcoma cells. The inhibitive rates of TRAIL to MG-63 cells were detected by MTT assay. The apoptosis induced by TRAIL in MG-63 human osteosarcoma cells was analyzed with FACS and TUNEL and the apoptotic bodies were observed by transmission electron microscope. MTT assay showed that the inhibitive rates of 500, 1 000,2 000 and 4 000 ng/mL TRAIL for 24 h were 10.1%, 24.3%,50.6% and 97.7% respectively. Flow cytometric analysis showed that after MG-63 cells were treated with 2 μg/mL TRAIL for 6 h,obvious apoptotic peak would immediately appear before diploid peak. Human soluble TRAIL protein can quickly kill MG-63 osteosarcoma cells selectively, and may have potential value for clinical treatment of osteosarcoma.

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

    Institute of Scientific and Technical Information of China (English)

    ZhuShou-Peng; ZhangLan-Sheng; 等

    1997-01-01

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

  13. NEW DESIGNED HMBA AGENTS AS INDUCERS OF ERYTHROLEUKEMIA CELL DIFFERENTIATION

    Institute of Scientific and Technical Information of China (English)

    王华力; 张世馥; 周建平; 章静波

    2002-01-01

    Objective.Searching for more potent and less toxic HMBA related agents. Methods.Human erythroleukemia cell K562,murine erythroleukemia cell (MEL) and its sub line MEL DS19 were used as target cells to select a cell line which is the most sensitive to HMBA,then analyzed the activity of inducing differentiation of two new designed HMBA derivatives:HMBPA [hexamethylenebi (3 pyridin) amide] and Co HDTA (ethylenediaminetetra acetic acid cobalt) using cell biology,cytochemical and molecular biology techniques. Results.We found that the MEL DS19 cells were most sensitive to HMBA (benzidine positive,B+ ~76% ).Co HDTA can inhibit the growth of MEL DS19,but induces differentiation just in a small population (B+ 2% ~4.5% ).Between 0.02~5μ mol/L,HMBPA induces 3% ~8% cells committed to differentiation with little inhibition of cell proliferation.1μ mol/L HMBPA and 2mmol/L HMBA together,can obviously increase the percentage of differentiated cell (B+ ~72% ),inhibit DNA synthesis and accelerate β globin transcription. Conclusion.The new HMBA derivatives may provide potential cancer differentiation inducers.

  14. Generation of Human Induced Pluripotent Stem Cells from Peripheral Blood Mononuclear Cells Using Sendai Virus.

    Science.gov (United States)

    Soares, Filipa A C; Pedersen, Roger A; Vallier, Ludovic

    2016-01-01

    This protocol describes the efficient isolation of peripheral blood mononuclear cells from circulating blood via density gradient centrifugation and subsequent generation of integration-free human induced pluripotent stem cells. Peripheral blood mononuclear cells are cultured for 9 days to allow expansion of the erythroblast population. The erythroblasts are then used to derive human induced pluripotent stem cells using Sendai viral vectors, each expressing one of the four reprogramming factors Oct4, Sox2, Klf4, and c-Myc.

  15. NETRIN-4 protects glioblastoma cells FROM temozolomide induced senescence.

    Directory of Open Access Journals (Sweden)

    Li Li

    Full Text Available Glioblastoma multiforme is the most common primary tumor of the central nervous system. The drug temozolomide (TMZ prolongs lifespan in many glioblastoma patients. The sensitivity of glioblastoma cells to TMZ is interfered by many factors, such as the expression of O-6-methylguanine-DNA methyltransferase (MGMT and activation of AKT signaling. We have recently identified the interaction between netrin-4 (NTN4 and integrin beta-4 (ITGB4, which promotes glioblastoma cell proliferation via activating AKT-mTOR signaling pathway. In the current work we have explored the effect of NTN4/ITGB4 interaction on TMZ induced glioblastoma cell senescence. We report here that the suppression of either ITGB4 or NTN4 in glioblastoma cell lines significantly enhances cellular senescence. The sensitivity of GBM cells to TMZ was primarily determined by the expression of MGMT. To omit the effect of MGMT, we concentrated on the cell lines devoid of expression of MGMT. NTN4 partially inhibited TMZ induced cell senescence and rescued AKT from dephosphorylation in U251MG cells, a cell line bearing decent levels of ITGB4. However, addition of exogenous NTN4 displayed no significant effect on TMZ induced senescence rescue or AKT activation in U87MG cells, which expressed ITGB4 at low levels. Furthermore, overexpression of ITGB4 combined with exogenous NTN4 significantly attenuated U87MG cell senescence induced by TMZ. These data suggest that NTN4 protects glioblastoma cells from TMZ induced senescence, probably via rescuing TMZ triggered ITGB4 dependent AKT dephosphorylation. This suggests that interfering the interaction between NTN4 and ITGB4 or concomitant use of the inhibitors of the AKT pathway may improve the therapeutic efficiency of TMZ.

  16. NETRIN-4 protects glioblastoma cells FROM temozolomide induced senescence.

    Science.gov (United States)

    Li, Li; Hu, Yizhou; Ylivinkka, Irene; Li, Huini; Chen, Ping; Keski-Oja, Jorma; Hyytiäinen, Marko

    2013-01-01

    Glioblastoma multiforme is the most common primary tumor of the central nervous system. The drug temozolomide (TMZ) prolongs lifespan in many glioblastoma patients. The sensitivity of glioblastoma cells to TMZ is interfered by many factors, such as the expression of O-6-methylguanine-DNA methyltransferase (MGMT) and activation of AKT signaling. We have recently identified the interaction between netrin-4 (NTN4) and integrin beta-4 (ITGB4), which promotes glioblastoma cell proliferation via activating AKT-mTOR signaling pathway. In the current work we have explored the effect of NTN4/ITGB4 interaction on TMZ induced glioblastoma cell senescence. We report here that the suppression of either ITGB4 or NTN4 in glioblastoma cell lines significantly enhances cellular senescence. The sensitivity of GBM cells to TMZ was primarily determined by the expression of MGMT. To omit the effect of MGMT, we concentrated on the cell lines devoid of expression of MGMT. NTN4 partially inhibited TMZ induced cell senescence and rescued AKT from dephosphorylation in U251MG cells, a cell line bearing decent levels of ITGB4. However, addition of exogenous NTN4 displayed no significant effect on TMZ induced senescence rescue or AKT activation in U87MG cells, which expressed ITGB4 at low levels. Furthermore, overexpression of ITGB4 combined with exogenous NTN4 significantly attenuated U87MG cell senescence induced by TMZ. These data suggest that NTN4 protects glioblastoma cells from TMZ induced senescence, probably via rescuing TMZ triggered ITGB4 dependent AKT dephosphorylation. This suggests that interfering the interaction between NTN4 and ITGB4 or concomitant use of the inhibitors of the AKT pathway may improve the therapeutic efficiency of TMZ.

  17. Lipopolysaccharide induces IFN-γ production in human NK cells

    Directory of Open Access Journals (Sweden)

    Leonid M Kanevskiy

    2013-01-01

    Full Text Available NK cells have been shown to play a regulatory role in sepsis. According to the current view, NK cells become activated via macrophages or dendritic cells primed by lipopolysaccharide (LPS. Recently TLR4 gene expression was detected in human NK cells suggesting the possibility of a direct action of LPS on NK cells. In this study, effects of LPS on NK cell cytokine production and cytotoxicity were studied using highly purified human NK cells. LPS induced IFN-γ production in the presence of IL-2 in cell populations containing >98% CD56+ cells. Surprisingly, in the same experiments LPS decreased NK cell degranulation. No significant expression of markers related to blood dendritic cells, monocytes or T or B lymphocytes in the NK cell preparations was observed; the portions of HLA-DRbright, CD14+, CD3+ and CD20+ cells amounted to less than 0.1% within the cell populations. No more than 0.2% of NK cells were shown to be slightly positive for surface TLR4 in our experimental system, although intracellular staining revealed moderate amounts of TLR4 inside the NK cell population. These cells were negative for surface CD14, the receptor participating in LPS recognition by TLR4. Incubation of NK cells with IL-2 or/and LPS did not lead to an increase in TLR4 surface expression. TLR4–CD56+ NK cells isolated by cell sorting secreted IFN-γ in response to LPS. Antibody to TLR4 did not block the LPS-induced increase in IFN-γ production. We have also shown that Re-form of LPS lacking outer core oligosaccharide and O-antigen induces less cytokine production in NK cells than full length LPS. We speculate that the polysaccharide fragments of LPS molecule may take part in LPS-induced IFN-γ production by NK cells. Collectively our data suggest the existence of a mechanism of LPS direct action on NK cells distinct from established TLR4-mediated signaling.

  18. Germ cell apoptosis induced by Ureaplasma urealyticum infection

    Institute of Scientific and Technical Information of China (English)

    Chen XU; Mei-Ge LU; Jing-Sheng FENG; Qiang-Su Guo; Yi-Fei WANG

    2001-01-01

    Aim: To study the effect of Ureaplasma urealyticum (UU) infection on germ cell apoptosis of male rats. Methods: Male rats were infected artificially with UU serotype 8 (T960) . Morphological changes of germ cells in the seminiferous tubules and the lumen of the epididymides were observed under the light microscope. Fluorescence-conjugated polyclonal antibodies to Fas and Fas ligand (FasL) were used to localize Fas and FasL. TUNEL staining of germ cells and Sertoli cells was performed by the AKPase method. TUNEL-positive rate ( % positive cells) and TUNEL-positive area (area occupied by stained cells) were analysed by KS400 Image Analysis System. The DNA laddering analysis was performed by agarose gels electrophoresis. Results: In those rats infected with UU: (1) Exfoliated germ cells were dramatically increased. Many multinucleated giant cells were found in the seminiferous tubules and the lumen of the epididymides. (2) The number of TUNEL-positive cells and the TUNEL-positive area were significantly increased.(3) The expression of Fas and FasL in germ cells and Sertoli cells was up-regulated. (4) Discrete bands of fragmented DNA were found in the testicular cells. Conclusion: In male rats, germ cell apoptosis was increased in UU infection.

  19. Generation of induced pluripotent stem cells from human β-thalassemia fibroblast cells

    Institute of Scientific and Technical Information of China (English)

    Yixuan Wang; Yonghua Jiang; Sheng Liu; Xiaofang Sun; Shaorong Gao

    2009-01-01

    @@ Dear Editor, Induced pluripotent stem (iPS) cells have recently been generated by directly introducing several transcrip-tion factors into differentiated human somatic cells, and these iPS cells show great similarities to embryo-derived ES cells [1-3].

  20. Signal transduction events in aluminum-induced cell death in tomato suspension cells

    NARCIS (Netherlands)

    Iakimova, E.T.; Kapchina-Toteva, V.M.; Woltering, E.J.

    2007-01-01

    In this study, some of the signal transduction events involved in AlCl3-induced cell death in tomato (Lycopersicon esculentum Mill.) suspension cells were elucidated. Cells treated with 100 ¿M AlCl3 showed typical features of programmed cell death (PCD) such as nuclear and cytoplasmic condensation.

  1. Matrine induces RIP3-dependent necroptosis in cholangiocarcinoma cells

    Science.gov (United States)

    Xu, Beibei; Xu, Minying; Tian, Yuan; Yu, Qiang; Zhao, Yujie; Chen, Xiong; Mi, Panying; Cao, Hanwei; Zhang, Bing; Song, Gang; Zhan, Yan-yan; Hu, Tianhui

    2017-01-01

    The development of acquired resistance to pro-apoptotic antitumor agents is a major impediment to the cure of cholangiocarcinoma (CCA). Antitumor drugs inducing non-apoptotic cell death are considered as a new approach to overcome such drug resistance. Here, we reported for the first time that matrine-induced necroptosis in CCA cell lines, differing from its classical role to induce apoptosis in many other kinds of cancer cells. CCA cells under matrine treatment exhibited typical necrosis-like but not apoptotic morphologic change. These matrine-induced morphologic change and cell death in CCA cells were greatly attenuated by necroptosis inhibitor necrostatin-1, but not apoptosis inhibitor z-VAD-fmk. Unlike many cancer cells with negative receptor-interacting protein 3 (RIP3) expression, moderate expression of RIP3 in CCA cells was observed and was required for matrine to induce necroptosis, which was switched to apoptosis after knocking down endogenous RIP3. Moreover, matrine could increase RIP3 expression level, which may facilitate the necroptosis process. Translocation of mixed lineage kinase-domain like (MLKL) from cytoplasm to plasma membrane as a downstream event of RIP3, as well as the increased production of reactive oxygen species (ROS) by RIP3/MLKL, was critical for matrine to induce necroptosis. In clinical study, we found RIP3 was lower but still moderately expressed in most CCA tissue samples compared with adjacent normal tissues. Taken together, we identified matrine as a necroptosis inducer in CCA by enhancing RIP3 expression and the following RIP3/MLKL/ROS signaling pathway, which provided new individualized strategies based on RIP3 expression to overcome chemoresistance in CCA therapy. PMID:28179994

  2. Generation of induced pluripotent stem cells from the pig

    Science.gov (United States)

    The value of stem cells has become increasingly evident in recent years with the advent of genetic engineering tools that allow site-specific modifications to the genome. The use of stem cells to induce modifications has several potential benefits for the livestock industry including improving anim...

  3. Acanthamoeba induces cell-cycle arrest in host cells.

    Science.gov (United States)

    Sissons, James; Alsam, Selwa; Jayasekera, Samantha; Kim, Kwang Sik; Stins, Monique; Khan, Naveed Ahmed

    2004-08-01

    Acanthamoeba can cause fatal granulomatous amoebic encephalitis (GAE) and eye keratitis. However, the pathogenesis and pathophysiology of these emerging diseases remain unclear. In this study, the effects of Acanthamoeba on the host cell cycle using human brain microvascular endothelial cells (HBMEC) and human corneal epithelial cells (HCEC) were determined. Two isolates of Acanthamoeba belonging to the T1 genotype (GAE isolate) and T4 genotype (keratitis isolate) were used, which showed severe cytotoxicity on HBMEC and HCEC, respectively. No tissue specificity was observed in their ability to exhibit binding to the host cells. To determine the effects of Acanthamoeba on the host cell cycle, a cell-cycle-specific gene array was used. This screened for 96 genes specific for host cell-cycle regulation. It was observed that Acanthamoeba inhibited expression of genes encoding cyclins F and G1 and cyclin-dependent kinase 6, which are proteins important for cell-cycle progression. Moreover, upregulation was observed of the expression of genes such as GADD45A and p130 Rb, associated with cell-cycle arrest, indicating cell-cycle inhibition. Next, the effect of Acanthamoeba on retinoblastoma protein (pRb) phosphorylation was determined. pRb is a potent inhibitor of G1-to-S cell-cycle progression; however, its function is inhibited upon phosphorylation, allowing progression into S phase. Western blotting revealed that Acanthamoeba abolished pRb phosphorylation leading to cell-cycle arrest at the G1-to-S transition. Taken together, these studies demonstrated for the first time that Acanthamoeba inhibits the host cell cycle at the transcriptional level, as well as by modulating pRb phosphorylation using host cell-signalling mechanisms. A complete understanding of Acanthamoeba-host cell interactions may help in developing novel strategies to treat Acanthamoeba infections.

  4. Light induced drug delivery into cancer cells.

    Science.gov (United States)

    Shamay, Yosi; Adar, Lily; Ashkenasy, Gonen; David, Ayelet

    2011-02-01

    Cell-penetrating peptides (CPPs) can be used for intracellular delivery of a broad variety of cargoes, including various nanoparticulate pharmaceutical carriers. However, the cationic nature of all CPP sequences, and thus lack of cell specificity, limits their in vivo use for drug delivery applications. Here, we have devised and tested a strategy for site-specific delivery of dyes and drugs into cancer cells by using polymers bearing a light activated caged CPP (cCPP). The positive charge of Lys residues on the minimum sequence of the CPP penetratin ((52)RRMKWKK(58)) was masked with photo-cleavable groups to minimize non-specific adsorption and cellular uptake. Once illuminated by UV light, these protecting groups were cleaved, the positively charged CPP regained its activity and facilitated rapid intracellular delivery of the polymer-dye or polymer-drug conjugates into cancer cells. We have found that a 10-min light illumination time was sufficient to enhance the penetration of the polymer-CPP conjugates bearing the proapoptotic peptide, (D)(KLAKLAK)(2), into 80% of the target cells, and to promote a 'switch' like cytotoxic activity resulting a shift from 100% to 10% in cell viability after 2 h. This report provides an example for tumor targeting by means of light activation of cell-penetrating peptides for intracellular drug delivery.

  5. Signal pathways involved in emodin-induced contraction of smooth muscle cells from rat colon

    Institute of Scientific and Technical Information of China (English)

    Tao Ma; Qing-Hui Qi; Jian Xu; Zuo-Liang Dong; Wen-Xiu Yang

    2004-01-01

    AIM: To investigate the effects induced by emodin on single smooth muscle cells from rat colon in vitro, and to determine the signal pathways involved.METHODS: Cells were isolated from the muscle layers of Wistar rat colon by enzymatic digestion. Cell length was measured by computerized image micrometry. Intracellular Ca2+ ([Ca2+]i) signals were studied using the fluorescent Ca2+ indicator fluo-3 and confocal microscopy. PKCα distribution at rest state or after stimulation was measured with immunofluorescence confocal microscopy.RESULTS: (1) Emodin dose-dependently caused colonic smooth muscle cells contraction; (2) emodin induced an increase in intracellular Ca2+ concentration; (3) the contractile responses induced by emodin were respectively inhibited by preincubation of the cells with ML-7 (an inhibitorof MLCK)and calphostin C (an inhibitor of PKC); (4) Incubation of cells with emodin caused translocation of PKCα from cytosolic area to the membrane.CONCLUSION: Emodin has a direct contractile effect on colonic smooth muscle cell. This signal cascade induced by emodin is initiated by increased [Ca2+]i and PKCα translocation,which in turn lead to the activation of MLCK and the suppression of MLCP. Both of them contribute to the emodininduced contraction.

  6. Liver sinusoidal endothelial cells induce immunosuppressive IL-10-producing Th1 cells via the Notch pathway.

    Science.gov (United States)

    Neumann, Katrin; Rudolph, Christine; Neumann, Christian; Janke, Marko; Amsen, Derk; Scheffold, Alexander

    2015-07-01

    Under homeostasis, liver sinusoidal endothelial cells (LSECs) shift intrahepatic T-cell responses towards tolerance. However, the role of LSECs in the regulation of T-cell-induced liver inflammation is less clear. Here, we studied the capacity of LSECs to modulate pro-inflammatory Th1-cell differentiation in mice. Using in vitro co-culture systems and subsequent cytokine analysis, we showed that LSECs induced high amounts of the anti-inflammatory cytokine IL-10 in developing Th1 cells. These LSEC-stimulated Th1 cells had no pro-inflammatory capacity in vivo but instead actively suppressed an inflammatory Th1-cell-induced delayed-type hypersensitivity reaction. Blockage of IL-10 signaling in vivo inhibited immunosuppressive activity of LSEC-stimulated Th1 cells. We identified the Notch pathway as a mechanism how LSECs trigger IL-10 expression in Th1 cells. LSECs expressed high levels of the Delta-like and Jagged family of Notch ligands and induced expression of the Notch target genes hes-1 and deltex-1 in Th1 cells. Blockade of Notch signaling selectively inhibited IL-10 induction in Th1 cells by LSECs. Our findings suggest that LSEC-induced IL-10 expression in Th1 cells via the Notch pathway may contribute to the control of hepatic inflammatory immune responses by induction of a self-regulatory mechanism in pro-inflammatory Th1 cells.

  7. Induced pluripotent stem cells and Parkinson's disease: modelling and treatment.

    Science.gov (United States)

    Xu, Xiaoyun; Huang, Jinsha; Li, Jie; Liu, Ling; Han, Chao; Shen, Yan; Zhang, Guoxin; Jiang, Haiyang; Lin, Zhicheng; Xiong, Nian; Wang, Tao

    2016-02-01

    Many neurodegenerative disorders, such as Parkinson's disease (PD), are characterized by progressive neuronal loss in different regions of the central nervous system, contributing to brain dysfunction in the relevant patients. Stem cell therapy holds great promise for PD patients, including with foetal ventral mesencephalic cells, human embryonic stem cells (hESCs) and human induced pluripotent stem cells (hiPSCs). Moreover, stem cells can be used to model neurodegenerative diseases in order to screen potential medication and explore their mechanisms of disease. However, related ethical issues, immunological rejection and lack of canonical grafting protocols limit common clinical use of stem cells. iPSCs, derived from reprogrammed somatic cells, provide new hope for cell replacement therapy. In this review, recent development in stem cell treatment for PD, using hiPSCs, as well as the potential value of hiPSCs in modelling for PD, have been summarized for application of iPSCs technology to clinical translation for PD treatment.

  8. Alcohol-induced steatosis in liver cells

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Alcohol-induced fatty liver (steatosis) was believed to result from excessive generation of reducing equivalents from ethanol metabolism, thereby enhancing fat accumulation. Recent findings have revealed a more complex picture in which ethanol oxidation is still required,but specific transcription as well as humoral factors also have important roles. Transcription factors involved include the sterol regulatory element binding protein 1 (SREBP-1)which is activated to induce genes that regulate lipid biosynthesis. Conversely, ethanol consumption causes a general down-regulation of lipid (fatty acid) oxidation, a reflection of inactivation of the peroxisome proliferatoractivated receptor-alpha (PPAR-α) that regulates genes involved in fatty acid oxidation. A third transcription factor is the early growth response-1 (Egr-1), which is strongly induced prior to the onset of steatosis. The activities of all these factors are governed by that of the principal regulatory enzyme, AMP kinase. Important humoral factors, including adiponectin, and tumor necrosis factor-α(TNF-α), also regulate alcohol-induced steatosis. Their levels are affected by alcohol consumption and by each other. This review will summarize the actions of these proteins in ethanol-elicited fatty liver. Because steatosis is now regarded as a significant risk factor for advanced liver pathology, an understanding of the molecular mechanisms in its etiology is essential for development of effective therapies.

  9. Cartilage regeneration by chondrogenic induced adult stem cells in osteoarthritic sheep model.

    Directory of Open Access Journals (Sweden)

    Chinedu C Ude

    Full Text Available OBJECTIVES: In this study, Adipose stem cells (ADSC and bone marrow stem cells (BMSC, multipotent adult cells with the potentials for cartilage regenerations were induced to chondrogenic lineage and used for cartilage regenerations in surgically induced osteoarthritis in sheep model. METHODS: Osteoarthritis was induced at the right knee of sheep by complete resection of the anterior cruciate ligament and medial meniscus following a 3-weeks exercise regimen. Stem cells from experimental sheep were culture expanded and induced to chondrogenic lineage. Test sheep received a single dose of 2 × 10(7 autologous PKH26-labelled, chondrogenically induced ADSCs or BMSCs as 5 mls injection, while controls received 5 mls culture medium. RESULTS: The proliferation rate of ADSCs 34.4 ± 1.6 hr was significantly higher than that of the BMSCs 48.8 ± 5.3 hr (P = 0.008. Chondrogenic induced BMSCs had significantly higher expressions of chondrogenic specific genes (Collagen II, SOX9 and Aggrecan compared to chondrogenic ADSCs (P = 0.031, 0.010 and 0.013. Grossly, the treated knee joints showed regenerated de novo cartilages within 6 weeks post-treatment. On the International Cartilage Repair Society grade scores, chondrogenically induced ADSCs and BMSCs groups had significantly lower scores than controls (P = 0.0001 and 0.0001. Fluorescence of the tracking dye (PKH26 in the injected cells showed that they had populated the damaged area of cartilage. Histological staining revealed loosely packed matrixes of de novo cartilages and immunostaining demonstrated the presence of cartilage specific proteins, Collagen II and SOX9. CONCLUSION: Autologous chondrogenically induced ADSCs and BMSCs could be promising cell sources for cartilage regeneration in osteoarthritis.

  10. Transforming growth factor-β synthesized by stromal cells and cancer cells participates in bone resorption induced by oral squamous cell carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, Ryosuke [Department of Oral Pathology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo (Japan); Department of Maxillofacial Surgery, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo (Japan); Kayamori, Kou [Department of Oral Pathology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo (Japan); Oue, Erika [Department of Oral Pathology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo (Japan); Department of Maxillofacial Surgery, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo (Japan); Sakamoto, Kei [Department of Oral Pathology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo (Japan); Harada, Kiyoshi [Department of Maxillofacial Surgery, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo (Japan); Yamaguchi, Akira, E-mail: akira.mpa@tmd.ac.jp [Department of Oral Pathology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo (Japan)

    2015-03-20

    Transforming growth factor beta (TGF-β) plays a significant role in the regulation of the tumor microenvironment. To explore the role of TGF-β in oral cancer-induced bone destruction, we investigated the immunohistochemical localization of TGF-β and phosphorylated Smad2 (p-Smad2) in 12 surgical specimens of oral squamous cell carcinoma (OSCC). These studies revealed TGF-β and p-Smad2 expression in cancer cells in all tested cases. Several fibroblasts located between cancer nests and resorbing bone expressed TGF-β in 10 out of 12 cases and p-Smad2 in 11 out of 12 cases. Some osteoclasts also exhibited p ∼ Smad2 expression. The OSCC cell line, HSC3, and the bone marrow-derived fibroblastic cell line, ST2, synthesized substantial levels of TGF-β. Culture media derived from HSC3 cells could stimulate Tgf-β1 mRNA expression in ST2 cells. Recombinant TGF-β1 could stimulate osteoclast formation induced by receptor activator of nuclear factor kappa-B ligand (RANKL) in RAW264 cells. TGF-β1 could upregulate the expression of p-Smad2 in RAW264 cells, and this action was suppressed by the addition of a neutralizing antibody against TGF-β or by SB431542. Transplantation of HSC3 cells onto the calvarial region of athymic mice caused bone destruction, associated with the expression of TGF-β and p-Smad2 in both cancer cells and stromal cells. The bone destruction was substantially inhibited by the administration of SB431542. The present study demonstrated that TGF-β synthesized by both cancer cells and stromal cells participates in the OSCC-induced bone destruction. - Highlights: • Cancer cell, fibroblastic cells, and osteoclasts at bone resorbing area by oral cancer exhibited TGF-β and p-Smad2. • TGF-β1 stimulated osteoclastogenesis induced by RAKL in RAW264 cell. • Xenograft model of oral cancer-induced bone resorption was substantially inhibited by SB431542. • TGF-β synthesized by both cancer cells and stromal cells participates in the OSCC-induced

  11. Significant differences in genotoxicity induced by retrovirus integration in human T cells and induced pluripotent stem cells.

    Science.gov (United States)

    Zheng, Weiyan; Wang, Yingjia; Chang, Tammy; Huang, He; Yee, Jiing-Kuan

    2013-04-25

    Retrovirus is frequently used in the genetic modification of mammalian cells and the establishment of induced pluripotent stem cells (iPSCs) via cell reprogramming. Vector-induced genotoxicity could induce profound effect on the physiology and function of these stem cells and their differentiated progeny. We analyzed retrovirus-induced genotoxicity in somatic cell Jurkat and two iPSC lines. In Jurkat cells, retrovirus frequently activated host gene expression and gene activation was not dependent on the distance between the integration site and the transcription start site of the host gene. In contrast, retrovirus frequently down-regulated host gene expression in iPSCs, possibly due to the action of chromatin silencing that spreads from the provirus to the nearby host gene promoter. Our data raises the issue that some of the phenotypic variability observed among iPSC clones derived from the same parental cell line may be caused by retrovirus-induced gene expression changes rather than by the reprogramming process itself. It also underscores the importance of characterizing retrovirus integration and carrying out risk assessment of iPSCs before they can be applied in basic research and clinics.

  12. Diphenylhydantoin-induced pure red cell aplasia.

    Science.gov (United States)

    Rusia, Usha; Malhotra, Purnima; Joshi, Panul

    2006-01-01

    Pure red cell aplasia is an uncommon complication of diphenylhydantoin therapy. It has not been reported in Indian literature. Awareness of the entity helps in establishing the cause of anaemia in these patients and alerts the physicians to the need of comprehensive haematological monitoring in these patients. A case of 58-year-old male who developed pure red cell aplasia following three months of diphenylhydantoin therapy is reported here.

  13. Novel synthetic organosulfur compounds induce apoptosis of human leukemic cells.

    Science.gov (United States)

    Wong, W W; Macdonald, S; Langler, R F; Penn, L Z

    2000-01-01

    It has been well documented that natural organosulfur compounds (OSCs) derived from plants such as garlic, onions and mahogany trees possess antiproliferative properties; however, the essential chemical features of the active OSC compounds remain unclear. To investigate the association between OSC structure and growth inhibitory activity, we synthesized novel relatives of dysoxysulfone, a natural OSC derived from the Fijian medicinal plant, Dysoxylum richii. In this study, we have examined the antiproliferative effects of these novel OSCs on a model human leukemic cell system and show that the compounds segregate into three groups. Group I, consisting of compounds A, B, G and J, did not affect either cell proliferation or the cell cycle profile of the leukemic cell lines. Group II, consisting of compounds F and H, induced the cells to undergo apoptosis from the G2/M phase of the cell cycle. Group III, consisting of compounds C, D, E and I, decreased cell proliferation and induced apoptosis throughout the cell cycle. The apoptotic agonists of Group II and III shared a common disulfide moiety, essential for leukemic cell cytotoxicity. Interestingly, Group II compounds did not affect cell viability of normal human diploid cells, suggesting the regions flanking the disulfide group contributes to the specificity of cell killing. Thus, we provide evidence that structure-activity analysis of natural products can identify novel compounds for the development of new therapeutics that can trigger apoptosis in a tumor-specific manner.

  14. Advances and applications of induced pluripotent stem cells.

    Science.gov (United States)

    Pietronave, Stefano; Prat, Maria

    2012-03-01

    Direct reprogramming of somatic cells into pluripotent cells is an emerging technology for creating patient-specific cells, and potentially opens new scenarios in medical and pharmacological fields. From the discovery of Shinya Yamanaka, who first obtained pluripotent cells from fibroblasts by retrovirus-derived ectopic expression of defined embryonic transcription factors, new methods have been developed to generate safe induced pluripotent stem (iPS) cells without genomic manipulations. This review will focus on the recent advances in iPS technology and their application in pharmacology and medicine.

  15. Glutaraldehyde induces cell shape changes in isolated outer hair cells from the inner ear.

    Science.gov (United States)

    Slepecky, N; Ulfendahl, M

    1988-01-01

    Individual isolated outer hair cells (OHCs) from the cochlea were maintained in a collagen gel and viewed in the light microscope. They were observed during fixation and processing for transmission electron microscopy and individual cells were selected for observation in the electron microscope. Application of glutaraldehyde at several concentrations caused OHCs to become shorter. Shrinkage occurred during dehydration but there was no further change during infiltration with the epoxy resin. Ultrastructural analysis of isolated cells fixed with glutaraldehyde and postfixed with osmium tetroxide showed that these cells were similar to cells fixed in the intact cochlea. The glutaraldehyde-induced cell shape change is similar to the shortening seen in intact OHCs in response to the application of solutions containing high potassium or caffeine. Application of glutaraldehyde to cells pretreated with potassium or caffeine caused further shortening. Glutaraldehyde-induced cell shape change was not blocked by the application of tetracaine, which did prevent potassium-induced and caffeine-induced shortening. Glutaraldehyde-induced cell shape change was not stopped by short treatment with N-ethylmaleimide, which did inhibit potassium-induced shortening. Results from these experiments suggest that the glutaraldehyde-induced OHC shape change is not caused by an effect on the membrane or by calcium activation of a contractile response. Shortening may be caused by shrinkage due to cross-linking of proteins.

  16. Elastase induces lung epithelial cell autophagy through placental growth factor

    Science.gov (United States)

    Hou, Hsin-Han; Cheng, Shih-Lung; Chung, Kuei-Pin; Kuo, Mark Yen-Ping; Yeh, Cheng-Chang; Chang, Bei-En; Lu, Hsuan-Hsuan; Wang, Hao-Chien; Yu, Chong-Jen

    2014-01-01

    Chronic obstructive pulmonary disease (COPD) is a devastating disease, which is associated with increasing mortality and morbidity. Therefore, there is a need to clearly define the COPD pathogenic mechanism and to explore effective therapies. Previous studies indicated that cigarette smoke (CS) induces autophagy and apoptosis in lung epithelial (LE) cells. Excessive ELANE/HNE (elastase, neutrophil elastase), a factor involved in protease-antiprotease imbalance and the pathogenesis of COPD, causes LE cell apoptosis and upregulates the expression of several stimulus-responsive genes. However, whether or not elastase induces autophagy in LE cell remains unknown. The level of PGF (placental growth factor) is higher in COPD patients than non-COPD controls. We hypothesize that elastase induces PGF expression and causes autophagy in LE cells. In this study, we demonstrated that porcine pancreatic elastase (PPE) induced PGF expression and secretion in LE cells in vitro and in vivo. The activation of MAPK8/JNK1 (mitogen-activated protein kinase 8) and MAPK14/p38alpha MAPK signaling pathways was involved in the PGF mediated regulation of the TSC (tuberous sclerosis complex) pathway and autophagy in LE cells. Notably, PGF-induced MAPK8 and MAPK14 signaling pathways mediated the inactivation of MTOR (mechanistic target of rapamycin), the upregulation of MAP1LC3B/LC3B (microtubule-associated protein 1 light chain 3 β) and the increase of autophagosome formation in mice. Furthermore, the PPE-induced autophagy promotes further apoptosis in vitro and in vivo. In summary, elastase-induced autophagy promotes LE cell apoptosis and pulmonary emphysema through the upregulation of PGF. PGF and its downstream MAPK8 and MAPK14 signaling pathways are potential therapeutic targets for the treatment of emphysema and COPD. PMID:24988221

  17. Towards Personalized Regenerative Cell Therapy: Mesenchymal Stem Cells Derived from Human Induced Pluripotent Stem Cells.

    Science.gov (United States)

    Lin, Lin; Bolund, Lars; Luo, Yonglun

    2016-01-01

    Mesenchymal stem cells (MSCs) are adult stem cells with the capacity of self-renewal and multilineage differentiation, and can be isolated from several adult tissues. However, isolating MSCs from adult tissues for cell therapy is hampered by the invasive procedure, the rarity of the cells and their attenuated proliferation capacity when cultivated and expanded in vitro. Human MSCs derived from induced pluripotent stem cells (iPSC-MSCs) have now evolved as a promising alternative cell source for MSCs and regenerative medicine. Several groups, including ours, have reported successful derivation of functional iPSC-MSCs and applied these cells in MSC-based therapeutic testing. Still, the current experience and understanding of iPSC-MSCs with respect to production methods, safety and efficacy are primitive. In this review, we highlight the methodological progress in iPSC-MSC research, describing the importance of choosing the right sources of iPSCs, iPSC reprogramming methods, iPSC culture systems, embryoid body intermediates, pathway inhibitors, basal medium, serum, growth factors and culture surface coating. We also highlight some progress in the application of iPSC-MSCs in direct cell therapy, tissue engineering and gene therapy.

  18. D609 induces vascular endothelial cells and marrow stromal cells differentiation into neuron-like cells

    Institute of Scientific and Technical Information of China (English)

    Nan WANG; Chun-qing DU; Shao-shan WANG; Kun XIE; Shang-li ZHANG; Jun-ying MIAO

    2004-01-01

    AIM: To investigate the effect of tricyclodecane-9-yl-xanthogenate (D609) on cell differentiation in vascular endothelial cells (VECs) and marrow stromal cells (MSCs). METHODS: Morphological changes were observed under phase contrast microscope. Electron microscope and immunostaining were used for VECs identification. The expressions of neuron-specific enolase (NSE) and glial fibrillary acidic protein (GFAP) were examined by immunohistochemistry. RESULTS: After 6 h of induction with D609, some VECs showed morphological changes characteristic of neurones. 9 h later, more VECs became neuron-like cells. About 30.8 % of VECs displayed positive NSE (P<0.01), while the expression of GFAP was negative. When MSCs were exposed to D609, the cells displayed neuronal morphologies, such as pyramidal cell bodies and processes formed extensive networks at 3 h. 6 h later, almost all of the cells exhibited a typical neuronal appearance, and 85.6 % of MSCs displayed intensive positive NSE, but GFAP did not express. CONCLUSION: D609 induces VECs and MSCs differentiation into neuron-like cells.

  19. Renal cell carcinoma with areas mimicking renal angiomyoadenomatous tumor/clear cell papillary renal cell carcinoma.

    Science.gov (United States)

    Petersson, Fredrik; Grossmann, Petr; Hora, Milan; Sperga, Maris; Montiel, Delia Perez; Martinek, Petr; Gutierrez, Maria Evelyn Cortes; Bulimbasic, Stela; Michal, Michal; Branzovsky, Jindrich; Hes, Ondrej

    2013-07-01

    We present a cohort of 8 renal carcinomas that displayed a variable (5%-95% extent) light microscopic appearance of renal angiomyoadenomatous tumor/clear cell papillary renal cell carcinoma (RAT/CCPRCC) without fulfilling the criteria for these tumors. All but 1 case predominantly (75%-95% extent) showed histopathologic features of conventional clear cell renal cell carcinoma. In 5 of 7 cases with mostly conventional clear renal cell carcinoma (CRCC) morphology, a diagnosis of CRCC was supported by the molecular genetic findings (presence of von Hippel-Lindau tumor suppressor [VHL] mutation and/or VHL promoter methylation and/or loss of heterozygosity [LOH] for 3p). Of the other 2 cases with predominantly characteristic CRCC morphology, 1 tumor did not reveal any VHL mutation, VHL promoter methylation, or LOH for 3p, and both chromosomes 7 and 17 were disomic, whereas the other tumor displayed polysomy for chromosomes 7 and 17 and no VHL mutation, VHL promoter methylation, or LOH for 3p. One tumor was composed primarily (95%) of distinctly RAT/CCPRCC-like morphology, and this tumor harbored a VHL mutation and displayed polysomy for chromosomes 7 and 17. Of the 5 cases with both histomorphologic features and molecular genetic findings of CRCC, we detected significant immunoreactivity for α-methylacyl-CoA racemase in 2 cases and strong diffuse immunopositivity for cytokeratin 7 in 3 cases. Despite the combination of positivity for α-methylacyl-CoA racemase and cytokeratin 7 in 2 cases, there was nothing to suggest of the possibility of a conventional papillary renal cell carcinoma with a predominance of clear cells.

  20. From teeth, skin, blood to heart : induced pluripotent stem cells as an in vitro model for cardiac disease

    NARCIS (Netherlands)

    Dambrot, Cheryl Susan

    2014-01-01

    Since the first reports of human induced pluripotent stem cells (hiPSC), the field of pluripotent stem cell (PSC) research has grown in leap and bounds, particularly in the area of (cardiac) disease modeling. This is in part because it is fairly easy to produce cardiomyocytes from hPSC and also ther

  1. In Vitro T-Cell Generation From Adult, Embryonic, and Induced Pluripotent Stem Cells: Many Roads to One Destination.

    Science.gov (United States)

    Smith, Michelle J; Webber, Beau R; Mohtashami, Mahmood; Stefanski, Heather E; Zúñiga-Pflücker, Juan Carlos; Blazar, Bruce R

    2015-11-01

    T lymphocytes are critical mediators of the adaptive immune system and have the capacity to serve as therapeutic agents in the areas of transplant and cancer immunotherapy. While T cells can be isolated and expanded from patients, T cells derived in vitro from both hematopoietic stem/progenitor cells (HSPCs) and human pluripotent stem cells (hPSCs) offer great potential advantages in generating a self-renewing source of T cells that can be readily genetically modified. T-cell differentiation in vivo is a complex process requiring tightly regulated signals; providing the correct signals in vitro to induce T-cell lineage commitment followed by their development into mature, functional, single positive T cells, is similarly complex. In this review, we discuss current methods for the in vitro derivation of T cells from murine and human HSPCs and hPSCs that use feeder-cell and feeder-cell-free systems. Furthermore, we explore their potential for adoption for use in T-cell-based therapies.

  2. Apoptosis of human pancreatic cancer cells induced by Triptolide

    Institute of Scientific and Technical Information of China (English)

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

    2008-01-01

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

  3. Mitochondrial control of cell death induced by hyperosmotic stress.

    Science.gov (United States)

    Criollo, Alfredo; Galluzzi, Lorenzo; Maiuri, M Chiara; Tasdemir, Ezgi; Lavandero, Sergio; Kroemer, Guido

    2007-01-01

    HeLa and HCT116 cells respond differentially to sorbitol, an osmolyte able to induce hypertonic stress. In these models, sorbitol promoted the phenotypic manifestations of early apoptosis followed by complete loss of viability in a time-, dose-, and cell type-specific fashion, by eliciting distinct yet partially overlapping molecular pathways. In HCT116 but not in HeLa cells, sorbitol caused the mitochondrial release of the caspase-independent death effector AIF, whereas in both cell lines cytochrome c was retained in mitochondria. Despite cytochrome c retention, HeLa cells exhibited the progressive activation of caspase-3, presumably due to the prior activation of caspase-8. Accordingly, caspase inhibition prevented sorbitol-induced killing in HeLa, but only partially in HCT116 cells. Both the knock-out of Bax in HCT116 cells and the knock-down of Bax in A549 cells by RNA interference reduced the AIF release and/or the mitochondrial alterations. While the knock-down of Bcl-2/Bcl-X(L) sensitized to sorbitol-induced killing, overexpression of a Bcl-2 variant that specifically localizes to mitochondria (but not of the wild-type nor of a endoplasmic reticulum-targeted form) strongly inhibited sorbitol effects. Thus, hyperosmotic stress kills cells by triggering different molecular pathways, which converge at mitochondria where pro- and anti-apoptotic members of the Bcl-2 family exert their control.

  4. DA-6034 Induces [Ca(2+)]i Increase in Epithelial Cells.

    Science.gov (United States)

    Yang, Yu-Mi; Park, Soonhong; Ji, Hyewon; Kim, Tae-Im; Kim, Eung Kweon; Kang, Kyung Koo; Shin, Dong Min

    2014-04-01

    DA-6034, a eupatilin derivative of flavonoid, has shown potent effects on the protection of gastric mucosa and induced the increases in fluid and glycoprotein secretion in human and rat corneal and conjunctival cells, suggesting that it might be considered as a drug for the treatment of dry eye. However, whether DA-6034 induces Ca(2+) signaling and its underlying mechanism in epithelial cells are not known. In the present study, we investigated the mechanism for actions of DA-6034 in Ca(2+) signaling pathways of the epithelial cells (conjunctival and corneal cells) from human donor eyes and mouse salivary gland epithelial cells. DA-6034 activated Ca(2+)-activated Cl(-) channels (CaCCs) and increased intracellular calcium concentrations ([Ca(2+)]i) in primary cultured human conjunctival cells. DA-6034 also increased [Ca(2+)]i in mouse salivary gland cells and human corneal epithelial cells. [Ca(2+)]i increase of DA-6034 was dependent on the Ca(2+) entry from extracellular and Ca(2+) release from internal Ca(2+) stores. Interestingly, these effects of DA-6034 were related to ryanodine receptors (RyRs) but not phospholipase C/inositol 1,4,5-triphosphate (IP3) pathway and lysosomal Ca(2+) stores. These results suggest that DA-6034 induces Ca(2+) signaling via extracellular Ca(2+) entry and RyRs-sensitive Ca(2+) release from internal Ca(2+) stores in epithelial cells.

  5. Cell cycle-arrested tumor cells exhibit increased sensitivity towards TRAIL-induced apoptosis

    Science.gov (United States)

    Ehrhardt, H; Wachter, F; Grunert, M; Jeremias, I

    2013-01-01

    Resting tumor cells represent a huge challenge during anticancer therapy due to their increased treatment resistance. TNF-related apoptosis-inducing ligand (TRAIL) is a putative future anticancer drug, currently in phases I and II clinical studies. We recently showed that TRAIL is able to target leukemia stem cell surrogates. Here, we tested the ability of TRAIL to target cell cycle-arrested tumor cells. Cell cycle arrest was induced in tumor cell lines and xenografted tumor cells in G0, G1 or G2 using cytotoxic drugs, phase-specific inhibitors or RNA interference against cyclinB and E. Biochemical or molecular arrest at any point of the cell cycle increased TRAIL-induced apoptosis. Accordingly, when cell cycle arrest was disabled by addition of caffeine, the antitumor activity of TRAIL was reduced. Most important for clinical translation, tumor cells from three children with B precursor or T cell acute lymphoblastic leukemia showed increased TRAIL-induced apoptosis upon knockdown of either cyclinB or cyclinE, arresting the cell cycle in G2 or G1, respectively. Taken together and in contrast to most conventional cytotoxic drugs, TRAIL exerts enhanced antitumor activity against cell cycle-arrested tumor cells. Therefore, TRAIL might represent an interesting drug to treat static-tumor disease, for example, during minimal residual disease. PMID:23744361

  6. Activated microglia cause reversible apoptosis of pheochromocytoma cells, inducing their cell death by phagocytosis.

    Science.gov (United States)

    Hornik, Tamara C; Vilalta, Anna; Brown, Guy C

    2016-01-01

    Some apoptotic processes, such as phosphatidylserine exposure, are potentially reversible and do not necessarily lead to cell death. However, phosphatidylserine exposure can induce phagocytosis of a cell, resulting in cell death by phagocytosis: phagoptosis. Phagoptosis of neurons by microglia might contribute to neuropathology, whereas phagoptosis of tumour cells by macrophages might limit cancer. Here, we examined the mechanisms by which BV-2 microglia killed co-cultured pheochromocytoma (PC12) cells that were either undifferentiated or differentiated into neuronal cells. We found that microglia activated by lipopolysaccharide rapidly phagocytosed PC12 cells. Activated microglia caused reversible phosphatidylserine exposure on and reversible caspase activation in PC12 cells, and caspase inhibition prevented phosphatidylserine exposur and decreased subsequent phagocytosis. Nitric oxide was necessary and sufficient to induce the reversible phosphatidylserine exposure and phagocytosis. The PC12 cells were not dead at the time they were phagocytised, and inhibition of their phagocytosis left viable cells. Cell loss was inhibited by blocking phagocytosis mediated by phosphatidylserine, MFG-E8, vitronectin receptors or P2Y6 receptors. Thus, activated microglia can induce reversible apoptosis of target cells, which is insufficient to cause apoptotic cell death, but sufficient to induce their phagocytosis and therefore cell death by phagoptosis.

  7. HAIR CELL-LIKE CELL GENERATION INDUCED BY NATURE CULTURE OF ADULT RAT AUDITORY EPITHELIUM

    Institute of Scientific and Technical Information of China (English)

    Liu Hui; Zhu Hongliang; Li Shengli; Yao Xiaobao; Wang Xiaoxia

    2006-01-01

    Objective To establish adult rat auditory epithelial cell culture and try to find precursor cells of auditory hair cells in vitro. Methods With refinement of culture media and techniques, cochlear sensory epithelial cells of adult rat were cultured. Immunocytochemistry and Bromodeoxyuridine (BrdU)labeling were used to detect properties and mitotic status of cultured cells. Results The cultured auditory epithelial cells showed a large, flat epithelial morphotype and expressed F-actin and cytokeratin, a subset of cells generated from auditory epithelium were labeled by calretinin, a specific marker of early hair cell. Conclusion Adult rat auditory epithelium can be induced to generate hair cell-like cells by nature culture, this phenomenon suggests that progenitor cells may exist in rat cochlea and they may give birth to new hair cells. Whether these progenitor cells are tissue specific stem cells is still need more study.

  8. Peroxide-induced cell death and lipid peroxidation in C6 glioma cells.

    Science.gov (United States)

    Linden, Arne; Gülden, Michael; Martin, Hans-Jörg; Maser, Edmund; Seibert, Hasso

    2008-08-01

    Peroxides are often used as models to induce oxidative damage in cells in vitro. The aim of the present study was to elucidate the role of lipid peroxidation in peroxide-induced cell death. To this end (i) the ability to induce lipid peroxidation in C6 rat astroglioma cells of hydrogen peroxide (H2O2), cumene hydroperoxide (CHP) and t-butyl hydroperoxide (t-BuOOH) (ii) the relation between peroxide-induced lipid peroxidation and cell death in terms of time and concentration dependency and (iii) the capability of the lipid peroxidation chain breaking alpha-tocopherol to prevent peroxide-induced lipid peroxidation and/or cell death were investigated. Lipid peroxidation was characterised by measuring thiobarbituric acid reactive substances (TBARS) and, by HPLC, malondialdehyde (MDA), 4-hydroxynonenal (4-HNE) and hexanal. Within 2 h CHP, t-BuOOH and H2O2 induced cell death with EC50 values of 59+/-9 microM, 290+/-30 microM and 12+/-1.1 mM, respectively. CHP and t-BuOOH, but not H2O2 induced lipid peroxidation in C6 cells with EC50 values of 15+/-14 microM and 130+/-33 microM, respectively. The TBARS measured almost exclusively consisted of MDA. 4-HNE was mostly not detectable. The concentration of hexanal slightly increased with increasing concentrations of organic peroxides. Regarding time and concentration dependency lipid peroxidation preceded cell death. Pretreatment with alpha-tocopherol (10 microM, 24 h) prevented both, peroxide-induced lipid peroxidation and cell death. The results strongly indicate a major role of lipid peroxidation in the killing of C6 cells by organic peroxides but also that lipid peroxidation is not involved in H2O2 induced cell death.

  9. Mechanisms of radiation-induced neoplastic cell transformation

    Energy Technology Data Exchange (ETDEWEB)

    Yang, T.C.H.; Tobias, C.A.

    1984-04-01

    Studies with cultured mammalian cells demonstrated clearly that radiation can transform cells directly and can enhance the cell transformation by oncogenic DNA viruses. In general, high-LET heavy-ion radiation can be more effective than X and gamma rays in inducing neoplastic cell transformation. Various experimental results indicate that radiation-induced DNA damage, most likely double-strand breaks, is important for both the initiation of cell transformation and for the enhancement of viral transformation. Some of the transformation and enhancement lesions can be repaired properly in the cell, and the amount of irrepairable lesions produced by a given dose depends on the quality of radiation. An inhibition of repair processes with chemical agents can increase the transformation frequency of cells exposed to radiation and/or oncogenic viruses, suggesting that repair mechanisms may play an important role in the radiation transformation. The progression of radiation-transformed cells appears to be a long and complicated process that can be modulated by some nonmutagenic chemical agents, e.g., DMSO. Normal cells can inhibit the expression of transforming properties of tumorigenic cells through an as yet unknown mechanism. The progression and expression of transformation may involve some epigenetic changes in the irradiated cells. 38 references, 15 figures, 1 table.

  10. HIV infection induces morphometrical changes on the oral (buccal mucosa and tongue) epithelial cells.

    Science.gov (United States)

    Pompermayer, Adriane Bastos; Gil, Francisca Berenice Dias; França, Beatriz Helena Sottile; Machado, Maria Ângela Naval; Trevilatto, Paula Cristina; Fernandes, Angela; de Lima, Antônio Adilson Soares

    2011-01-01

    The aim of this study was to assess morphological and morphometrical alterations of oral squamous epithelial cells in type 1 HIV infected individuals. Oral smears were collected from tongue and buccal mucosa of 30 HIV infected (experimental) and 30 non-infected (control) individuals by liquid-based exfoliative cytology. The cells were morphologically analyzed and the nuclear area (NA), the cytoplasmic area (CA) and the nucleus-to-cytoplasm area ratio (NA/CA) were calculated. No morphological differences were found between the groups. The mean values of CA were decreased in tongue (P=.00006) and buccal mucosa (P=.00242) in HIV infected individual, while mean values of NA were increased (P=.00308 and .00095, respectively) in the same group. NA/CA ratio for experimental group was increased in both collected places, with P=.00001 (tongue) and P=.00000 (buccal mucosa). This study revealed that HIV infection was able to induce morphometrical changes on the oral epithelial cells.

  11. Simvastatin suppresses breast cancer cell proliferation induced by senescent cells

    NARCIS (Netherlands)

    Liu, Su; Uppal, Harpreet; Demaria, Marco; Desprez, Pierre-Yves; Campisi, Judith; Kapahi, Pankaj

    2015-01-01

    Cellular senescence suppresses cancer by preventing the proliferation of damaged cells, but senescent cells can also promote cancer though the pro-inflammatory senescence-associated secretory phenotype (SASP). Simvastatin, an HMG-coA reductase inhibitor, is known to attenuate inflammation and preven

  12. Recreation-induced changes in boreal bird communities in protected areas.

    Science.gov (United States)

    Kangas, K; Luoto, M; Ihantola, A; Tomppo, E; Siikamäki, P

    2010-09-01

    The impacts of human-induced disturbance on birds have been studied in growing extent, but there are relatively few studies about the effects of recreation on forest bird communities in protected areas. In this paper, the relative importance of recreation as well as environmental variables on bird communities in Oulanka National Park, in northeastern Finland, was investigated using general additive models (GAM). Bird data collected using the line transect method along hiking trails and in undisturbed control areas were related to number of visits, area of tourism infrastructure, and habitat variables. We further examined the impact of spatial autocorrelation by calculating an autocovariate term for GAMs. Our results indicate that number of visits affects the occurrence and composition of bird communities, but it had no impact on total species richness. Open-cup nesters breeding on the ground showed strongest negative response to visitor pressure, whereas the open-cup nesters nesting in trees and shrubs were more tolerant. For cavity-nesting species, recreation had no significant impact. The contribution of the number of visits was generally low also in models in which it was selected, and the occurrence of birds was mainly determined by habitat characteristics of the area. However, our results show that the recreation-induced disturbance with relatively low visitor pressure can have negative impacts on some bird species and groups of species and should be considered in management of protected areas with recreational activities.

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

    Directory of Open Access Journals (Sweden)

    Huang Peng

    2010-04-01

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

  14. Langerhans Cells Facilitate UVB-induced Epidermal Carcinogenesis

    Science.gov (United States)

    Lewis, Julia M.; Bürgler, Christina D.; Freudzon, Marianna; Golubets, Kseniya; Gibson, Juliet F.; Filler, Renata B.; Girardi, Michael

    2015-01-01

    Ultraviolet B (UVB) light is considered the major environmental inducer of human keratinocyte DNA mutations, including within the tumor-suppressor gene p53, and chronic exposure is associated with cutaneous squamous cell carcinoma (SCC) formation. Langerhans cells (LC) comprise a dendritic network within the suprabasilar epidermis, yet the role of LC in UVB-induced carcinogenesis is largely unknown. Herein, we show that LC-intact epidermis develops UVB-induced tumors more readily than LC-deficient epidermis. While levels of epidermal cyclopyrimidine dimers (CPD) following acute UVB exposure are equivalent in the presence or absence of LC, chronic UVB-induced p53 mutant clonal islands expand more readily in association with LC which remain largely intact and are preferentially found in proximity to the expanding mutant keratinocyte populations. The observed LC facilitation of mutant p53 clonal expansion is completely αβ and γδ T-cell independent, and is associated with increased intraepidermal expression of interleukin (IL)-22 and the presence of group 3 innate lymphoid cells (ILC3). These data demonstrate that LC play a key role in UVB-induced cutaneous carcinogenesis, and suggest that LC locally stimulate keratinocyte proliferation and innate immune cells that provoke tumor outgrowth. PMID:26053049

  15. Jasmonic acid signaling modulates ozone-induced hypersensitive cell death.

    Science.gov (United States)

    Rao, M V; Lee, H; Creelman, R A; Mullet, J E; Davis, K R

    2000-09-01

    Recent studies suggest that cross-talk between salicylic acid (SA)-, jasmonic acid (JA)-, and ethylene-dependent signaling pathways regulates plant responses to both abiotic and biotic stress factors. Earlier studies demonstrated that ozone (O(3)) exposure activates a hypersensitive response (HR)-like cell death pathway in the Arabidopsis ecotype Cvi-0. We now have confirmed the role of SA and JA signaling in influencing O(3)-induced cell death. Expression of salicylate hydroxylase (NahG) in Cvi-0 reduced O(3)-induced cell death. Methyl jasmonate (Me-JA) pretreatment of Cvi-0 decreased O(3)-induced H(2)O(2) content and SA concentrations and completely abolished O(3)-induced cell death. Cvi-0 synthesized as much JA as did Col-0 in response to O(3) exposure but exhibited much less sensitivity to exogenous Me-JA. Analyses of the responses to O(3) of the JA-signaling mutants jar1 and fad3/7/8 also demonstrated an antagonistic relationship between JA- and SA-signaling pathways in controlling the magnitude of O(3)-induced HR-like cell death.

  16. Human induced pluripotent stem cells on autologous feeders.

    Directory of Open Access Journals (Sweden)

    Kazutoshi Takahashi

    Full Text Available BACKGROUND: For therapeutic usage of induced Pluripotent Stem (iPS cells, to accomplish xeno-free culture is critical. Previous reports have shown that human embryonic stem (ES cells can be maintained in feeder-free condition. However, absence of feeder cells can be a hostile environment for pluripotent cells and often results in karyotype abnormalities. Instead of animal feeders, human fibroblasts can be used as feeder cells of human ES cells. However, one still has to be concerned about the existence of unidentified pathogens, such as viruses and prions in these non-autologous feeders. METHODOLOGY/PRINCIPAL FINDINGS: This report demonstrates that human induced Pluripotent Stem (iPS cells can be established and maintained on isogenic parental feeder cells. We tested four independent human skin fibroblasts for the potential to maintain self-renewal of iPS cells. All the fibroblasts tested, as well as their conditioned medium, were capable of maintaining the undifferentiated state and normal karyotypes of iPS cells. Furthermore, human iPS cells can be generated on isogenic parental fibroblasts as feeders. These iPS cells carried on proliferation over 19 passages with undifferentiated morphologies. They expressed undifferentiated pluripotent cell markers, and could differentiate into all three germ layers via embryoid body and teratoma formation. CONCLUSIONS/SIGNIFICANCE: These results suggest that autologous fibroblasts can be not only a source for iPS cells but also be feeder layers. Our results provide a possibility to solve the dilemma by using isogenic fibroblasts as feeder layers of iPS cells. This is an important step toward the establishment of clinical grade iPS cells.

  17. Rhinovirus infection induces cytotoxicity and delays wound healing in bronchial epithelial cells

    Directory of Open Access Journals (Sweden)

    Constantopoulos Andreas G

    2005-10-01

    Full Text Available Abstract Background Human rhinoviruses (RV, the most common triggers of acute asthma exacerbations, are considered not cytotoxic to the bronchial epithelium. Recent observations, however, have questioned this knowledge. The aim of this study was to evaluate the ability of RV to induce epithelial cytotoxicity and affect epithelial repair in-vitro. Methods Monolayers of BEAS-2B bronchial epithelial cells, seeded at different densities were exposed to RV serotypes 1b, 5, 7, 9, 14, 16. Cytotoxicity was assessed chromatometrically. Epithelial monolayers were mechanically wounded, exposed or not to RV and the repopulation of the damaged area was assessed by image analysis. Finally epithelial cell proliferation was assessed by quantitation of proliferating cell nuclear antigen (PCNA by flow cytometry. Results RV1b, RV5, RV7, RV14 and RV16 were able to induce considerable epithelial cytotoxicity, more pronounced in less dense cultures, in a cell-density and dose-dependent manner. RV9 was not cytotoxic. Furthermore, RV infection diminished the self-repair capacity of bronchial epithelial cells and reduced cell proliferation. Conclusion RV-induced epithelial cytotoxicity may become considerable in already compromised epithelium, such as in the case of asthma. The RV-induced impairment on epithelial proliferation and self-repair capacity may contribute to the development of airway remodeling.

  18. Quantification of depletion-induced adhesion of Red Blood Cells

    CERN Document Server

    Steffen, Patrick; Wagner, Christian

    2012-01-01

    Red blood cells (RBC) are known to form aggregates in the forms of rouleaux due to the presence of plasma proteins under physiological conditions. Rouleaux formation can be also induced in vitro by the addition of macromolecules to the RBC solution. Current data on the adhesion strength between red blood cells in their natural discocyte shapes mostly rely on indirect measurements like flow chamber experiments, but on the single cell level data is lacking. Here we present measurements on the dextran induced aggregation of red blood cells by use of atomic force microscopy based single cell force spectroscopy (SCFS). The effects of dextran concentration and molecular weight on the interaction energy of adhering RBCs was determined. The results are in good agreement with a model based on the depletion effect and former experimental studies.

  19. Inducible cell death in plant immunity

    DEFF Research Database (Denmark)

    Hofius, Daniel; Tsitsigiannis, Dimitrios I; Jones, Jonathan D G;

    2006-01-01

    Programmed cell death (PCD) occurs during vegetative and reproductive plant growth, as typified by autumnal leaf senescence and the terminal differentiation of the endosperm of cereals which provide our major source of food. PCD also occurs in response to environmental stress and pathogen attack,...

  20. Manipulating Somatic Cells to Remove Barriers in Induced Pluripotent Stem Cell Reprogramming

    OpenAIRE

    Chung, Julia

    2013-01-01

    Development leads unidirectionally towards a more restricted cell fate that is usually stable. However, it has been proven that developmental systems are reversible by the success of animal cloning of a differentiated somatic genome through somatic cell nuclear transfer (SCNT). Recently, reprogramming of somatic cells to a pluripotent embryonic stem cell (ESC)-like state by introducing defined transcripton factor has been achieved, resulting in the generation of induced pluripotent stem cells...

  1. Borrelia burgdorferi Spirochetes Induce Mast Cell Activation and Cytokine Release

    Science.gov (United States)

    Talkington, Jeffrey; Nickell, Steven P.

    1999-01-01

    The Lyme disease spirochete, Borrelia burgdorferi, is introduced into human hosts via tick bites. Among the cell types present in the skin which may initially contact spirochetes are mast cells. Since spirochetes are known to activate a variety of cell types in vitro, we tested whether B. burgdorferi spirochetes could activate mast cells. We report here that freshly isolated rat peritoneal mast cells or mouse MC/9 mast cells cultured in vitro with live or freeze-thawed B. burgdorferi spirochetes undergo low but detectable degranulation, as measured by [5-3H] hydroxytryptamine release, and they synthesize and secrete the proinflammatory cytokine tumor necrosis factor alpha (TNF-α). In contrast to findings in previous studies, where B. burgdorferi-associated activity was shown to be dependent upon protein lipidation, mast cell TNF-α release was not induced by either lipidated or unlipidated recombinant OspA. This activity was additionally shown to be protease sensitive and surface expressed. Finally, comparisons of TNF-α-inducing activity in known low-, intermediate-, and high-passage B. burgdorferi B31 isolates demonstrated passage-dependent loss of activity, indicating that the activity is probably plasmid encoded. These findings document the presence in low-passage B. burgdorferi spirochetes of a novel lipidation-independent activity capable of inducing cytokine release from host cells. PMID:10024550

  2. Linalool Induces Cell Cycle Arrest and Apoptosis in Leukemia Cells and Cervical Cancer Cells through CDKIs.

    Science.gov (United States)

    Chang, Mei-Yin; Shieh, Den-En; Chen, Chung-Chi; Yeh, Ching-Sheng; Dong, Huei-Ping

    2015-01-01

    Plantaginaceae, a popular traditional Chinese medicine, has long been used for treating various diseases from common cold to cancer. Linalool is one of the biologically active compounds that can be isolated from Plantaginaceae. Most of the commonly used cytotoxic anticancer drugs have been shown to induce apoptosis in susceptible tumor cells. However, the signaling pathway for apoptosis remains undefined. In this study, the cytotoxic effect of linalool on human cancer cell lines was investigated. Water-soluble tetrazolium salts (WST-1) based colorimetric cellular cytotoxicity assay, was used to test the cytotoxic ability of linalool against U937 and HeLa cells, and flow cytometry (FCM) and genechip analysis were used to investigate the possible mechanism of apoptosis. These results demonstrated that linalool exhibited a good cytotoxic effect on U937 and HeLa cells, with the IC50 value of 2.59 and 11.02 μM, respectively, compared with 5-FU with values of 4.86 and 12.31 μM, respectively. After treating U937 cells with linalool for 6 h, we found an increased sub-G1 peak and a dose-dependent phenomenon, whereby these cells were arrested at the G0/G1 phase. Furthermore, by using genechip analysis, we observed that linalool can promote p53, p21, p27, p16, and p18 gene expression. Therefore, this study verified that linalool can arrest the cell cycle of U937 cells at the G0/G1 phase and can arrest the cell cycle of HeLa cells at the G2/M phase. Its mechanism facilitates the expression of the cyclin-dependent kinases inhibitors (CDKIs) p53, p21, p27, p16, and p18, as well as the non-expression of cyclin-dependent kinases (CDKs) activity.

  3. Linalool Induces Cell Cycle Arrest and Apoptosis in Leukemia Cells and Cervical Cancer Cells through CDKIs

    Directory of Open Access Journals (Sweden)

    Mei-Yin Chang

    2015-11-01

    Full Text Available Plantaginaceae, a popular traditional Chinese medicine, has long been used for treating various diseases from common cold to cancer. Linalool is one of the biologically active compounds that can be isolated from Plantaginaceae. Most of the commonly used cytotoxic anticancer drugs have been shown to induce apoptosis in susceptible tumor cells. However, the signaling pathway for apoptosis remains undefined. In this study, the cytotoxic effect of linalool on human cancer cell lines was investigated. Water-soluble tetrazolium salts (WST-1 based colorimetric cellular cytotoxicity assay, was used to test the cytotoxic ability of linalool against U937 and HeLa cells, and flow cytometry (FCM and genechip analysis were used to investigate the possible mechanism of apoptosis. These results demonstrated that linalool exhibited a good cytotoxic effect on U937 and HeLa cells, with the IC50 value of 2.59 and 11.02 μM, respectively, compared with 5-FU with values of 4.86 and 12.31 μM, respectively. After treating U937 cells with linalool for 6 h, we found an increased sub-G1 peak and a dose-dependent phenomenon, whereby these cells were arrested at the G0/G1 phase. Furthermore, by using genechip analysis, we observed that linalool can promote p53, p21, p27, p16, and p18 gene expression. Therefore, this study verified that linalool can arrest the cell cycle of U937 cells at the G0/G1 phase and can arrest the cell cycle of HeLa cells at the G2/M phase. Its mechanism facilitates the expression of the cyclin-dependent kinases inhibitors (CDKIs p53, p21, p27, p16, and p18, as well as the non-expression of cyclin-dependent kinases (CDKs activity.

  4. Current progress and prospects of induced pluripotent stem cells

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Induced pluripotent stem(iPS) cells are derived from somatic cells by ectopic expression of few transcription factors.Like embryonic stem(ES) cells,iPS cells are able to self-renew indefinitely and to differentiate into all types of cells in the body.iPS cells hold great promise for regenerative medicine,because iPS cells circumvent not only immunological rejection but also ethical issues.Since the first report on the derivation of iPS cells in 2006,many laboratories all over the world started research on iPS cells and have made significant progress.This paper reviews recent progress in iPS cell research,including the methods to generate iPS cells,the molecular mechanism of reprogramming in the formation of iPS cells,and the potential applications of iPS cells in cell replacement therapy.Current problems that need to be addressed and the prospects for iPS research are also discussed.

  5. Retinoic acid from retinal pigment epithelium induces T regulatory cells.

    Science.gov (United States)

    Kawazoe, Yuko; Sugita, Sunao; Keino, Hiroshi; Yamada, Yukiko; Imai, Ayano; Horie, Shintaro; Mochizuki, Manabu

    2012-01-01

    Primary cultured retinal pigment epithelial (RPE) cells can convert T cells into T regulatory cells (Tregs) through inhibitory factor(s) including transforming growth factor β (TGFβ) in vitro. Retinoic acid (RA) enhances induction of CD4(+) Tregs in the presence of TGFβ. We investigated whether RA produced by RPE cells can promote generation of Tregs. We found that in vitro, RA-treated T cells expressed high levels of Foxp3 in the presence of recombinant TGFβ. In GeneChip analysis, cultured RPE cells constitutively expressed RA-associated molecules such as RA-binding proteins, enzymes, and receptors. RPE from normal mice, but not vitamin A-deficient mice, contained significant levels of TGFβ. RPE-induced Tregs from vitamin A-deficient mice failed to suppress activation of target T cells. Only a few Foxp3(+) T cells were found in intraocular cells from vitamin A-deficient experimental autoimmune uveitis (EAU) mice, whereas expression was higher in cells from normal EAU mice. RA receptor antagonist-pretreated or RA-binding protein-siRNA-transfected RPE cells failed to convert CD4(+) T cells into Tregs. Our data support the hypothesis that RPE cells produce RA, thereby enabling bystander T cells to be converted into Tregs through TGFβ promotion, which can then participate in the establishment of immune tolerance in the eye.

  6. Santa Barbara Littoral Cell CRSMP Sensitive Habitat Areas 2009

    Data.gov (United States)

    California Department of Resources — Ecological areas as identified and collected by BEACON and submitted to CSMW as part of the Central Coast (from Pt. Conception to Pt. Mugu) Coastal Regional Sediment...

  7. Long-term maintenance of human induced pluripotent stem cells by automated cell culture system.

    Science.gov (United States)

    Konagaya, Shuhei; Ando, Takeshi; Yamauchi, Toshiaki; Suemori, Hirofumi; Iwata, Hiroo

    2015-11-17

    Pluripotent stem cells, such as embryonic stem cells and induced pluripotent stem (iPS) cells, are regarded as new sources for cell replacement therapy. These cells can unlimitedly expand under undifferentiated conditions and be differentiated into multiple cell types. Automated culture systems enable the large-scale production of cells. In addition to reducing the time and effort of researchers, an automated culture system improves the reproducibility of cell cultures. In the present study, we newly designed a fully automated cell culture system for human iPS maintenance. Using an automated culture system, hiPS cells maintained their undifferentiated state for 60 days. Automatically prepared hiPS cells had a potency of differentiation into three germ layer cells including dopaminergic neurons and pancreatic cells.

  8. Dietary squid ink polysaccharide induces goblet cells to protect small intestine from chemotherapy induced injury.

    Science.gov (United States)

    Zuo, Tao; Cao, Lu; Xue, Changhu; Tang, Qing-Juan

    2015-03-01

    Gastrointestinal mucositis induced by chemotherapy is associated with alterations of intestinal barrier function due to the potential damage induced by anti-cancer drugs on the epithelial cells. Goblet cells, an important epithelial lining in the intestine, contribute to innate immunity by secreting mucin glycoproteins. Employing a mouse model of chemotherapy induced intestinal mucosal immunity injury by cyclophosphamide, we demonstrated for the first time that polysaccharide from the ink of Ommastrephes bartramii (OBP) enhanced Cyto18, which is a mucin expression in goblet cells. The up-regulation of mucins by OBP relied on the augmented quantity of goblet cells, but not on the changes in the ultrastructure of endoplasmic reticulum (ER). Our results may have important implications for enhanced immunopotentiation function of functional OBP on intestinal mucosal immunity against intestinal disorders involving inflammation and infection.

  9. Chestnut extract induces apoptosis in AGS human gastric cancer cells.

    Science.gov (United States)

    Lee, Hyun Sook; Kim, Eun Ji; Kim, Sun Hyo

    2011-06-01

    In Korea, chestnut production is increasing each year, but consumption is far below production. We investigated the effect of chestnut extracts on antioxidant activity and anticancer effects. Ethanol extracts of raw chestnut (RCE) or chestnut powder (CPE) had dose-dependent superoxide scavenging activity. Viable numbers of MDA-MD-231 human breast cancer cells, DU145 human prostate cancer cells, and AGS human gastric cancer cells decreased by 18, 31, and 69%, respectively, following treatment with 200 µg/mL CPE for 24 hr. CPE at various concentrations (0-200 µg/mL) markedly decreased AGS cell viability and increased apoptotic cell death dose and time dependently. CPE increased the levels of cleaved caspase-8, -7, -3, and poly (ADP-ribose) polymerase in a dose-dependent manner but not cleaved caspase-9. CPE exerted no effects on Bcl-2 and Bax levels. The level of X-linked inhibitor of apoptosis protein decreased within a narrow range following CPE treatment. The levels of Trail, DR4, and Fas-L increased dose-dependently in CPE-treated AGS cells. These results show that CPE decreases growth and induces apoptosis in AGS gastric cancer cells and that activation of the death receptor pathway contributes to CPE-induced apoptosis in AGS cells. In conclusion, CPE had more of an effect on gastric cancer cells than breast or prostate cancer cells, suggesting that chestnuts would have a positive effect against gastric cancer.

  10. Alterations in cell surface area and deformability of individual human red blood cells in stored blood

    CERN Document Server

    Park, HyunJoo; Lee, SangYun; Kim, Kyoohyun; Sohn, Yong-Hak; Jang, Seongsoo; Park, YongKeun

    2015-01-01

    The functionality and viability of stored human red blood cells (RBCs) is an important clinical issue in transfusion. To systematically investigate changes in stored whole blood, the hematological properties of individual RBCs were quantified in blood samples stored for various periods with and without a preservation solution called CPDA-1. With 3-D quantitative phase imaging techniques, the optical measurements of the 3-D refractive index (RI) distributions and membrane fluctuations were done at the individual cell level. From the optical measurements, the morphological (volume, surface area and sphericity), biochemical (hemoglobin content and concentration), and mechanical parameters (dynamic membrane fluctuation) were simultaneously quantified to investigate the functionalities and their progressive alterations in stored RBCs. Our results show that the stored RBCs without CPDA-1 had a dramatic morphological transformation from discocytes to spherocytes within 2 weeks which was accompanied with significant ...

  11. Large area magnetic micropallet arrays for cell colony sorting.

    Science.gov (United States)

    Cox-Muranami, Wesley A; Nelson, Edward L; Li, G P; Bachman, Mark

    2016-01-01

    A new micropallet array platform for adherent cell colony sorting has been developed. The platform consisted of thousands of square plastic pallets, 270 μm by 270 μm on each side, large enough to hold a single colony of cells. Each pallet included a magnetic core, allowing them to be collected with a magnet after being released using a microscope mounted laser system. The micropallets were patterned from 1002F epoxy resist and were fabricated on translucent, gold coated microscope slides. The gold layer was used as seed for electroplating the ferromagnetic cores within every individual pallet. The gold layer also facilitated the release of each micropallet during laser release. This array allows for individual observation, sorting and collection of isolated cell colonies for biological cell colony research. In addition to consistent release and recovery of individual colonies, we demonstrated stable biocompatibility and minimal loss in imaging quality compared to previously developed micropallet arrays.

  12. Fluorescence lifetime imaging of induced pluripotent stem cells

    Science.gov (United States)

    Uchugonova, Aisada; Batista, Ana; König, Karsten

    2014-02-01

    The multiphoton FLIM tomograph MPTflex with its flexible scan head, articulated arm, and the tunable femtosecond laser source was employed to study cell monolayers and 3D cell clusters. FLIM was performed with 250 ps temporal resolution and submicron special resolution using time-correlated single photon counting. The autofluorescence based on NAD(P)H and flavins/flavoproteins has been measured in mouse embryonic fibroblasts, induced pluripotent stem cells (iPS cells) originated from mouse embryonic fibroblasts and non-proliferative mouse embryonic fibroblasts.

  13. Nonhuman Primate Induced Pluripotent Stem Cells in Regenerative Medicine

    Directory of Open Access Journals (Sweden)

    Yuehong Wu

    2012-01-01

    Full Text Available Among the various species from which induced pluripotent stem cells have been derived, nonhuman primates (NHPs have a unique role as preclinical models. Their relatedness to humans and similar physiology, including central nervous system, make them ideal for translational studies. We review here the progress made in deriving and characterizing iPS cell lines from different NHP species. We focus on iPS cell lines from the marmoset, a small NHP in which several human disease states can be modeled. The marmoset can serve as a model for the implementation of patient-specific autologous cell therapy in regenerative medicine.

  14. Gingerol sensitizes TRAIL-induced apoptotic cell death of glioblastoma cells

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Dae-Hee, E-mail: leedneo@gmail.com [Departments of Surgery and Pharmacology and Cell Biology, School of Medicine, University of Pittsburgh, Pittsburgh, PA (United States); Kim, Dong-Wook [Department of Microbiology, Immunology, and Cancer Biology, University of VA (United States); Jung, Chang-Hwa [Division of Metabolism and Functionality Research, Korea Food Research Institute (Korea, Republic of); Lee, Yong J. [Departments of Surgery and Pharmacology and Cell Biology, School of Medicine, University of Pittsburgh, Pittsburgh, PA (United States); Park, Daeho, E-mail: daehopark@gist.ac.kr [School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju 500-712 (Korea, Republic of)

    2014-09-15

    Glioblastoma multiforme (GBM) is the most lethal and aggressive astrocytoma of primary brain tumors in adults. Although there are many clinical trials to induce the cell death of glioblastoma cells, most glioblastoma cells have been reported to be resistant to TRAIL-induced apoptosis. Here, we showed that gingerol as a major component of ginger can induce TRAIL-mediated apoptosis of glioblastoma. Gingerol increased death receptor (DR) 5 levels in a p53-dependent manner. Furthermore, gingerol decreased the expression level of anti-apoptotic proteins (survivin, c-FLIP, Bcl-2, and XIAP) and increased pro-apoptotic protein, Bax and truncate Bid, by generating reactive oxygen species (ROS). We also found that the sensitizing effects of gingerol in TRAIL-induced cell death were blocked by scavenging ROS or overexpressing anti-apoptotic protein (Bcl-2). Therefore, we showed the functions of gingerol as a sensitizing agent to induce cell death of TRAIL-resistant glioblastoma cells. This study gives rise to the possibility of applying gingerol as an anti-tumor agent that can be used for the purpose of combination treatment with TRAIL in TRAIL-resistant glioblastoma tumor therapy. - Highlights: • Most GBM cells have been reported to be resistant to TRAIL-induced apoptosis. • Gingerol enhances the expression level of anti-apoptotic proteins by ROS. • Gingerol enhances TRAIL-induced apoptosis through actions on the ROS–Bcl2 pathway.

  15. Crocin suppresses tumor necrosis factor-alpha-induced cell death of neuronally differentiated PC-12 cells.

    Science.gov (United States)

    Soeda, S; Ochiai, T; Paopong, L; Tanaka, H; Shoyama, Y; Shimeno, H

    2001-11-01

    Crocus sativus L. is used in Chinese traditional medicine to treat some disorders of the central nervous system. Crocin is an ethanol-extractable component of Crocus sativus L.; it is reported to prevent ethanol-induced impairment of learning and memory in mice. In this study, we demonstrate that crocin suppresses the effect of tumor necrosis factor (TNF)-alpha on neuronally differentiated PC-12 cells. PC-12 cells dead from exposure to TNF-alpha show apoptotic morphological changes and DNA fragmentation. These hallmark features of cell death did not appear in cells treated in the co-presence of 10 microM crocin. Moreover, crocin suppressed the TNF-alpha-induced expression of Bcl-Xs and LICE mRNAs and simultaneously restored the cytokine-induced reduction of Bcl-X(L) mRNA expression. The modulating effects of crocin on the expression of Bcl-2 family proteins led to a marked reduction of a TNF-alpha-induced release of cytochrome c from the mitochondria. Crocin also blocked the cytochrome c-induced activation of caspase-3. To learn how crocin exhibits these anti-apoptotic actions in PC-12 cells, we tested the effect of crocin on PC-12 cell death induced by daunorubicin. We found that crocin inhibited the effect of daunorubicin as well. Our findings suggest that crocin inhibits neuronal cell death induced by both internal and external apoptotic stimuli.

  16. Epigenetic rejuvenation of mesenchymal stromal cells derived from induced pluripotent stem cells

    NARCIS (Netherlands)

    Frobel, Joana; Hemeda, Hatim; Lenz, Michael; Abagnale, Giulio; Joussen, Sylvia; Denecke, Bernd; Sarić, Tomo; Zenke, Martin; Wagner, Wolfgang

    2014-01-01

    Standardization of mesenchymal stromal cells (MSCs) remains a major obstacle in regenerative medicine. Starting material and culture expansion affect cell preparations and render comparison between studies difficult. In contrast, induced pluripotent stem cells (iPSCs) assimilate toward a ground stat

  17. Human induced pluripotent stem cells: A disruptive innovation.

    Science.gov (United States)

    De Vos, J; Bouckenheimer, J; Sansac, C; Lemaître, J-M; Assou, S

    2016-01-01

    This year (2016) will mark the 10th anniversary of the discovery of induced pluripotent stem cells (iPSCs). The finding that the transient expression of four transcription factors can radically remodel the epigenome, transcriptome and metabolome of differentiated cells and reprogram them into pluripotent stem cells has been a major and groundbreaking technological innovation. In this review, we discuss the major applications of this technology that we have grouped in nine categories: a model to study cell fate control; a model to study pluripotency; a model to study human development; a model to study human tissue and organ physiology; a model to study genetic diseases in a dish; a tool for cell rejuvenation; a source of cells for drug screening; a source of cells for regenerative medicine; a tool for the production of human organs in animals.

  18. Apoptosis induced by propolis in human hepatocellular carcinoma cell line.

    Science.gov (United States)

    Choi, Y H; Lee, W Y; Nam, S Y; Choi, K C; Park, Y E

    1999-07-01

    Propolis has been reported to exhibit a wide spectrum of activities including antibiotic, antiviral, anti-inflammatory, immunostimulatory and tumor carcinostatic properties. We showed propolis induced apoptosis in a human hepatoma cell line (SNU449) by FITC-Annexin V/PI staining. We also compared the apoptosis inducing effect between Korean and Commercial (Sigma # p-1010) propolis. There was no difference on apoptosis between them.

  19. Heterogeneity in predisposition of hepatic cells to be induced into pancreatic endocrine cells by PDX-1

    Institute of Scientific and Technical Information of China (English)

    Shun Lu; Wei-Ping Wang; Xiao-Fei Wang; Zong-Mei Zheng; Ping Chen; Kang-Tao Ma; Chun-Yan Zhou

    2005-01-01

    AIM: The role of Pancreatic and Duodenal Homeobox-1(PDX-1) as a major regulator of pancreatic development determines the function and phenotype of β cell. In this study, potential plasticity of liver cells into pancreatic endocrine cells induced by PDX-1 was evaluated.METHODS: Human hepatoma cell line HepG2 was stably transfected with mammalian expression plasmid pcDNA3-PDX encoding human PDX-1 gene. Ectopic expression of PDX-1 and insulin were detected by RT-PCR,Western blot and/or immunostaining. PDX-1+ HepG2 cells were transplanted under renal capsule of STZ-induced diabetic nude mice (n = 16) to examine the inducing effect in vivo.RESULTS: Exogenous PDX-1 transgene was proved to express effectively in HepG2 cell at both mRNA and protein levels. The expression of endogenous insulin and some βcell-specific differentiation markers and transcription factors were not induced in PDX-1+ HepG2 cells. When transplanted under renal capsule of STZ-induced diabetic nude mice, PDX-1+ HepG2 cells did not generate insulinproducing cells. These data indicated that stable transfected PDX-1 could not convert hepatoma cell line HepG2 to pancreatic cells in vitro or in vivo. Mature hepatocytes might need much more complicated or rigorous conditions to be shifted to insulin-producing cells.CONCLUSION: The expression of exogenous PDX-1 is not sufficient to induce relatively mature hepatocytes differentiating into insulin-producing cells.

  20. Mechanisms of rotenone-induced neurotoxicity in PC 12 cells

    Institute of Scientific and Technical Information of China (English)

    Wei Han; Lizhong Sun; Jiafeng Chen; Ming Chang; Hongyan Huo; Linsen Hu

    2008-01-01

    BACKGROUND: Rotenone-induced neurotoxicity in PC 12 cells has been widely used to study the pathogenesis of Parkinson's disease. However, the precise mechanisms underlying rotenone-induced dopaminergic neuronal degeneration in Parkinson's disease remains unclear.OBJECTIVE: To establish rotenone-induced neurotoxicity in PC 12 cells, and to investigate the possible action pathways to rotenone-induced neural cell injury at the protein level.DESIGN, TIME AND SETTING: A controlled proteomics study was performed at the Department of Nearology, First Hospital, Jilin University between March 2006 and March 2007.MATERIALS: PC 12 cells were obtained from Shanghai Cell Bank of Chinese Academy of Sciences, China.Rotenone was provided by Sigma, USA.METHODS: PC 12 cells in logarithmic growth phase were treated under experimental and control conditions, respectively. A total of 0.5 μ mol/L rotenone, or the same amount of Dulbecco's modified eagle's medium (DMEM), was added in the experimental and control conditions, respectively.MAIN OUTCOME MEASURES: Following 72 hours of rotenone treatment, cellular survival rate was determined by methyl thiazolyl tetrazolium assay, and apoptotic changes were detected by Hoechst 33342 staining. Total cellular protein was extracted to acquire differential protein expression data utilizing two-dimensional differential in-gel electrophoresis. To identify differential protein spots, matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF-MS) was used.RESULTS: In the MTT assay, the experimental condition induced significantly less cell survival compared to the control condition (P < 0.01 ). Hoechst 33342 staining revealed a larger number of apoptotic cells under the experimental condition compared to the control condition (P < 0.01 ), as determined by the presence of nuclear condensation, pyknosis, and nuclear fragmentation. Two-dimensional electrophoresis results showed that the differential expression of protein

  1. Therapeutic opportunities: Telomere maintenance in inducible pluripotent stem cells

    Energy Technology Data Exchange (ETDEWEB)

    Gourronc, Francoise A. [Department of Microbiology, University of Iowa (United States); Klingelhutz, Aloysius J., E-mail: al-klingelhutz@uiowa.edu [Department of Microbiology, University of Iowa (United States)

    2012-02-01

    It has been demonstrated that exogenous expression of a combination of transcription factors can reprogram differentiated cells such as fibroblasts and keratinocytes into what have been termed induced pluripotent stem (iPS) cells. These iPS cells are capable of differentiating into all the tissue lineages when placed in the right environment and, in the case of mouse cells, can generate chimeric mice and be transmitted through the germline. Safer and more efficient methods of reprogramming are rapidly being developed. Clearly, iPS cells present a number of exciting possibilities, including disease modeling and therapy. A major question is whether the nuclei of iPS cells are truly rejuvenated or whether they might retain some of the marks of aging from the cells from which they were derived. One measure of cellular aging is the telomere. In this regard, recent studies have demonstrated that telomeres in iPS cells may be rejuvenated. They are not only elongated by reactivated telomerase but they are also epigenetically modified to be similar but not identical to embryonic stem cells. Upon differentiation, the derivative cells turn down telomerase, the telomeres begin to shorten again, and the telomeres and the genome are returned to an epigenetic state that is similar to normal differentiated somatic cells. While these preliminary telomere findings are promising, the overall genomic integrity of reprogrammed cells may still be problematic and further studies are needed to examine the safety and feasibility of using iPS cells in regenerative medicine applications.

  2. Moxonidine and rilmenidine injected into the medial septal area reduces the salivation induced by pilocarpine.

    Science.gov (United States)

    Saad, Wilson Abrão; de Arruda Camargo, Luis Antonio; Simões, Silvio; Saad, William Abrão; Guarda, Renata Saad; Guarda, Ismael Francisco Mota Siqueira

    2004-05-31

    We determined the effects of moxonidine and rilmenidine 20 nmol (alpha(2)-adrenergic and imidazoline receptor agonists) injected into the medial septal area (MSA) on the pilocarpine-induced salivation, when injected intraperitoneally (i.p.), of male Holtzman rats weighing 250-300 g, with stainless-steel cannula implanted into the MSA. The rats were anesthetized with zoletil 50 mg kg(-1) b.wt. (tiletamine chloridrate 125.0 mg and zolazepan chloridrate 125.0 mg) into quadriceps muscle intramuscularly (IM), saliva was collected using pre-weighed small cotton balls inserted in the animal's mouth. The pre-treatment with moxonidine injected into the MSA reduced the salivation induced by pilocarpine (1 mg kg(-1)) injected i.p. (12+/-3 mg min(-1)) vs. control (99+/-9 mg min(-1)). The pre-treatment with rilmenidine 40 nmol also reduced the salivation induce by pilocarpine injected i.p. (20+/-5 mg min(-1)) vs. control (94+/-7 mg min(-1)). Idazoxan 40 nmol (imidazoline receptor antagonist) injected into the MSA previous to moxonidine and rilmenidine partially blocked the effect of moxonidine and totally blocked the rilmenidine effect in pilocarpine-induced salivation injected i.p. (60+/-8 and 95+/-10 mg min(-1), respectively). Yohimbine 40 nmol (alpha(2)-adrenergic receptor antagonist) injected into the MSA previously to moxonidine and rilmenidine partially blocked the moxonidine effect but produced no change on the rilmenidine effect on i.p. pilocarpine-induced salivation (70+/-6 and 24+/-6 mg min(-1), respectively). Injection of these alpha(2)-adrenergic and imidazoline agonists and antagonists agents i.p. produced no change on i.p. pilocarpine-induced salivation. These results show that central, but not peripheral, injection of alpha(2)-adrenergic and imidazoline agonists' agents inhibit pilocarpine-induced salivation. Idazoxan, an imidazoline receptor antagonist, totally inhibits the rilmenidine effect and partially inhibits the moxonidine effect on pilocarpine-induced

  3. Fucoidan inhibits angiogenesis induced by multiple myeloma cells.

    Science.gov (United States)

    Liu, Fen; Luo, Guoping; Xiao, Qing; Chen, Liping; Luo, Xiaohua; Lv, Jinglong; Chen, Lixue

    2016-10-01

    Multiple myeloma (MM) remains an incurable hematological neoplasms. Our previous studies showed that Fucoidan possessed anti-myeloma effect by inducing apoptosis and inhibiting invasion of myeloma cells. In this study, we evaluated the effect of Fucoidan on angiogenesis induced by human myeloma cells and elucidated its possible mechanisms. Multiple myeloma cells were treated with Fucoidan at different concentrations, then the conditioned medium (CM) was collected. The levels of VEGF in the CM were tested by ELISA. The results showed that Fucoidan significantly decreased VEGF secretion by RPMI-8226 and U266 cells. The tube formation assay and migration test on human umbilical vein endothelial cells (HUVECs) were used to examine the effect of Fucoidan on angiogenesis induced by human myeloma cells. The results showed that Fucoidan decreased HUVECs formed tube structures and inhibited HUVECs migration, and suppressed the angiogenic ability of multiple myeloma RPMI-8226 and U266 cells in a dose-dependent manner. The study also showed that Fucoidan downregulated the expression of several kinds of proteins, which may be correlated with the reduction of angiogenesis induced by myeloma cells. Moreover, results were compared from normoxic and hypoxic conditions, they showed that Fucoidan had anti-angiogenic activity. Furthermore, in a multiple myeloma xenograft mouse model, it indicated that Fucoidan negatively affected tumor growth and angiogenesis in vivo. In conclusion, our results demonstrate that Fucoidan was able to interfere with angiogenesis of multiple myeloma cells both in vitro and in vivo and may have a substantial potential in the treatment of MM.

  4. Signaling events in pathogen-induced macrophage foam cell formation.

    Science.gov (United States)

    Shaik-Dasthagirisaheb, Yazdani B; Mekasha, Samrawit; He, Xianbao; Gibson, Frank C; Ingalls, Robin R

    2016-08-01

    Macrophage foam cell formation is a key event in atherosclerosis. Several triggers induce low-density lipoprotein (LDL) uptake by macrophages to create foam cells, including infections with Porphyromonas gingivalis and Chlamydia pneumoniae, two pathogens that have been linked to atherosclerosis. While gene regulation during foam cell formation has been examined, comparative investigations to identify shared and specific pathogen-elicited molecular events relevant to foam cell formation are not well documented. We infected mouse bone marrow-derived macrophages with P. gingivalis or C. pneumoniae in the presence of LDL to induce foam cell formation, and examined gene expression using an atherosclerosis pathway targeted plate array. We found over 30 genes were significantly induced in response to both pathogens, including PPAR family members that are broadly important in atherosclerosis and matrix remodeling genes that may play a role in plaque development and stability. Six genes mainly involved in lipid transport were significantly downregulated. The response overall was remarkably similar and few genes were regulated in a pathogen-specific manner. Despite very divergent lifestyles, P. gingivalis and C. pneumoniae activate similar gene expression profiles during foam cell formation that may ultimately serve as targets for modulating infection-elicited foam cell burden, and progression of atherosclerosis.

  5. Apoptotic pathway induced by noscapine in human myelogenous leukemic cells.

    Science.gov (United States)

    Heidari, Nastaran; Goliaei, Bahram; Moghaddam, Parvaneh Rahimi; Rahbar-Roshandel, Nahid; Mahmoudian, Massoud

    2007-11-01

    It has been shown that noscapine, an opium-derived phthalideisoquinoline alkaloid that is currently being used as an oral antitussive drug, induces apoptosis in myeloid leukemia cells. The molecular mechanism responsible for the anticancer effects of noscapine is poorly understood. In the current study, the apoptotic effects of noscapine on two myeloid cell lines, apoptosis-proficient HL60 cells and apoptosis-resistant K562 cells, were analyzed. An increase in the activity of caspase-2, -3, -6, -8 and -9, poly(ADP ribose) polymerase cleavage, detection of phosphatidylserine on the outer layer of the cell membrane, nucleation of chromatin, and DNA fragmentation suggested the induction of apoptosis. Noscapine increased the Bax/Bcl-2 ratio with a significant decrease of Bcl-2 expression accompanied with Bcl-2 phosphorylation. Using an inhibitory approach, the activation of the caspase cascade involved in the noscapine-induced apoptosis was analyzed. We observed no inhibitory effect of the caspase-8 inhibitor on caspase-9 activity. In view of these results and taking into consideration that K562 cells are Fas-null, we suggested that caspase-8 is activated in a Fas-independent manner downstream of caspase-9. In conclusion, noscapine can induce apoptosis in both apoptosis-proficient and apoptosis-resistant leukemic cells, and it can be a novel candidate in the treatment of hematological malignancies.

  6. Recombinant soluble TRAIL induces apoptosis of cancer cells

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

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

  7. Proteasome inhibitors attenuated cholesterol-induced cardiac hypertrophy in H9c2 cells

    Science.gov (United States)

    Lee, Hyunjung; Park, Jinyoung; Kim, Eunice EunKyeong; Yoo, Young Sook; Song, Eun Joo

    2016-01-01

    The Ubiquitin proteasome system (UPS) plays roles in protein degradation, cell cycle control, and growth and inflammatory cell signaling. Dysfunction of UPS in cardiac diseases has been seen in many studies. Cholesterol acts as an inducer of cardiac hypertrophy. In this study, the effect of proteasome inhibitors on the cholesterol-induced hypertrophic growth in H9c2 cells is examined in order to observe whether UPS is involved in cardiac hypertrophy. The treatment of proteasome inhibitors MG132 and Bortezomib markedly reduced cellular surface area and mRNA expression of β-MHC in cholesterol-induced cardiac hypertrophy. In addition, activated AKT and ERK were significantly attenuated by MG132 and Bortezomib in cholesterol-induced cardiac hypertrophy. We demonstrated that cholesterol-induced cardiac hypertrophy was suppressed by proteasome inhibitors. Thus, regulatory mechanism of cholesterol-induced cardiac hypertrophy by proteasome inhibitors may provide a new therapeutic strategy to prevent the progression of heart failure. [BMB Reports 2016; 49(5): 270-275] PMID:26592933

  8. Statins and voriconazole induce programmed cell death in Acanthamoeba castellanii.

    Science.gov (United States)

    Martín-Navarro, Carmen M; López-Arencibia, Atteneri; Sifaoui, Ines; Reyes-Batlle, María; Valladares, Basilio; Martínez-Carretero, Enrique; Piñero, José E; Maciver, Sutherland K; Lorenzo-Morales, Jacob

    2015-05-01

    Members of the genus Acanthamoeba are facultative pathogens of humans, causing a sight-threatening keratitis and a life-threatening encephalitis. In order to treat those infections properly, it is necessary to target the treatment not only to the trophozoite but also to the cyst. Furthermore, it may be advantageous to avoid parasite killing by necrosis, which may induce local inflammation. We must also avoid toxicity of host tissue. Many drugs which target eukaryotes are known to induce programmed cell death (PCD), but this process is poorly characterized in Acanthamoeba. Here, we study the processes of programmed cell death in Acanthamoeba, induced by several drugs, such as statins and voriconazole. We tested atorvastatin, fluvastatin, simvastatin, and voriconazole at the 50% inhibitory concentrations (IC50s) and IC90s that we have previously established. In order to evaluate this phenomenon, we investigated the DNA fragmentation, one of the main characteristics of PCD, with quantitative and qualitative techniques. Also, the changes related to phosphatidylserine exposure on the external cell membrane and cell permeability were studied. Finally, because caspases are key to PCD pathways, caspase activity was evaluated in Acanthamoeba. All the drugs assayed in this study induced PCD in Acanthamoeba. To the best of our knowledge, this is the first study where PCD induced by drugs is described quantitatively and qualitatively in Acanthamoeba.

  9. Noscapine induces apoptosis in human glioma cells by an apoptosis-inducing factor-dependent pathway.

    Science.gov (United States)

    Newcomb, Elizabeth W; Lukyanov, Yevgeniy; Smirnova, Iva; Schnee, Tona; Zagzag, David

    2008-07-01

    Previously, we identified noscapine as a small molecule inhibitor of the hypoxia-inducible factor-1 pathway in hypoxic human glioma cells and human umbilical vein endothelial cells. Noscapine is a nontoxic ingredient in cough medicine currently used in clinical trials for patients with non-Hodgkin's lymphoma or chronic lymphocytic leukemia to assess antitumor efficacy. Here, we have evaluated the sensitivity of four human glioma cell lines to noscapine-induced apoptosis. Noscapine was a potent inhibitor of proliferation and inducer of apoptosis. Induction of apoptosis was associated with activation of the c-jun N-terminal kinase signaling pathway concomitant with inactivation of the extracellular signal regulated kinase signaling pathway and phosphorylation of the antiapoptotic protein Bcl-2. Noscapine-induced apoptosis was associated with the release of mitochondrial proteins apoptosis-inducing factor (AIF) and/or cytochrome c. In some glioma cell lines, only AIF release occurred without cytochrome c release or poly (ADP-ribose) polymerase cleavage. Knock-down of AIF decreased noscapine-induced apoptosis. Our results suggest the potential importance of noscapine as a novel agent for use in patients with glioblastoma owing to its low toxicity profile and its potent anticancer activity.

  10. The physics of photon induced degradation of perovskite solar cells

    Directory of Open Access Journals (Sweden)

    Pranav H. Joshi

    2016-11-01

    Full Text Available Lead-trihalide perovskite solar cells are an important photovoltaic technology. We investigate the effect of light induced degradation on perovskite solar cells. During exposure, the open-circuit voltage (Voc of the device increases, whereas the short-circuit current (Isc shows a decrease. The degradation can be completely recovered using thermal annealing in dark. We develop a model based on light induced generation of ions and migration of these ions inside the material to explain the changes in Isc, Voc, capacitance and dark current upon light exposure and post-exposure recovery. There was no change in defect density in the material upon exposure.

  11. The physics of photon induced degradation of perovskite solar cells

    Science.gov (United States)

    Joshi, Pranav H.; Zhang, Liang; Hossain, Istiaque M.; Abbas, Hisham A.; Kottokkaran, Ranjith; Nehra, Satyapal P.; Dhaka, Mahendra; Noack, Max; Dalal, Vikram L.

    2016-11-01

    Lead-trihalide perovskite solar cells are an important photovoltaic technology. We investigate the effect of light induced degradation on perovskite solar cells. During exposure, the open-circuit voltage (Voc) of the device increases, whereas the short-circuit current (Isc) shows a decrease. The degradation can be completely recovered using thermal annealing in dark. We develop a model based on light induced generation of ions and migration of these ions inside the material to explain the changes in Isc, Voc, capacitance and dark current upon light exposure and post-exposure recovery. There was no change in defect density in the material upon exposure.

  12. Chromomycin A2 induces autophagy in melanoma cells.

    Science.gov (United States)

    Guimarães, Larissa Alves; Jimenez, Paula Christine; Sousa, Thiciana da Silva; Freitas, Hozana Patrícia S; Rocha, Danilo Damasceno; Wilke, Diego Veras; Martín, Jesús; Reyes, Fernando; Deusdênia Loiola Pessoa, Otília; Costa-Lotufo, Letícia Veras

    2014-12-04

    The present study highlights the biological effects of chromomycin A2 toward metastatic melanoma cells in culture. Besides chromomycin A2, chromomycin A3 and demethylchromomycin A2 were also identified from the extract derived from Streptomyces sp., recovered from Paracuru Beach, located in the northeast region of Brazil. The cytotoxic activity of chromomycin A2 was evaluated across a panel of human tumor cell lines, which found IC50 values in the nM-range for exposures of 48 and 72 h. MALME-3M, a metastatic melanoma cell line, showed the highest sensitivity to chromomycin A2 after 48h incubation, and was chosen as a model to investigate this potent cytotoxic effect. Treatment with chromomycin A2 at 30 nM reduced cell proliferation, but had no significant effect upon cell viability. Additionally, chromomycin A2 induced accumulation of cells in G0/G1 phase of the cell cycle, with consequent reduction of S and G2/M and unbalanced expression of cyclins. Chromomycin A2 treated cells depicted several cellular fragments resembling autophagosomes and increased expression of proteins LC3-A and LC3-B. Moreover, exposure to chromomycin A2 also induced the appearance of acidic vacuolar organelles in treated cells. These features combined are suggestive of the induction of autophagy promoted by chromomycin A2, a feature not previously described for chromomycins.

  13. Chromomycin A2 Induces Autophagy in Melanoma Cells

    Science.gov (United States)

    Guimarães, Larissa Alves; Jimenez, Paula Christine; Sousa, Thiciana da Silva; Freitas, Hozana Patrícia S.; Rocha, Danilo Damasceno; Wilke, Diego Veras; Martín, Jesús; Reyes, Fernando; Pessoa, Otília Deusdênia Loiola; Costa-Lotufo, Letícia Veras

    2014-01-01

    The present study highlights the biological effects of chromomycin A2 toward metastatic melanoma cells in culture. Besides chromomycin A2, chromomycin A3 and demethylchromomycin A2 were also identified from the extract derived from Streptomyces sp., recovered from Paracuru Beach, located in the northeast region of Brazil. The cytotoxic activity of chromomycin A2 was evaluated across a panel of human tumor cell lines, which found IC50 values in the nM-range for exposures of 48 and 72 h. MALME-3M, a metastatic melanoma cell line, showed the highest sensitivity to chromomycin A2 after 48h incubation, and was chosen as a model to investigate this potent cytotoxic effect. Treatment with chromomycin A2 at 30 nM reduced cell proliferation, but had no significant effect upon cell viability. Additionally, chromomycin A2 induced accumulation of cells in G0/G1 phase of the cell cycle, with consequent reduction of S and G2/M and unbalanced expression of cyclins. Chromomycin A2 treated cells depicted several cellular fragments resembling autophagosomes and increased expression of proteins LC3-A and LC3-B. Moreover, exposure to chromomycin A2 also induced the appearance of acidic vacuolar organelles in treated cells. These features combined are suggestive of the induction of autophagy promoted by chromomycin A2, a feature not previously described for chromomycins. PMID:25486109

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

    Directory of Open Access Journals (Sweden)

    Laila Ziko

    2015-01-01

    Full Text Available 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.

  15. Chromomycin A2 Induces Autophagy in Melanoma Cells

    Directory of Open Access Journals (Sweden)

    Larissa Alves Guimarães

    2014-12-01

    Full Text Available The present study highlights the biological effects of chromomycin A2 toward metastatic melanoma cells in culture. Besides chromomycin A2, chromomycin A3 and demethylchromomycin A2 were also identified from the extract derived from Streptomyces sp., recovered from Paracuru Beach, located in the northeast region of Brazil. The cytotoxic activity of chromomycin A2 was evaluated across a panel of human tumor cell lines, which found IC50 values in the nM-range for exposures of 48 and 72 h. MALME-3M, a metastatic melanoma cell line, showed the highest sensitivity to chromomycin A2 after 48h incubation, and was chosen as a model to investigate this potent cytotoxic effect. Treatment with chromomycin A2 at 30 nM reduced cell proliferation, but had no significant effect upon cell viability. Additionally, chromomycin A2 induced accumulation of cells in G0/G1 phase of the cell cycle, with consequent reduction of S and G2/M and unbalanced expression of cyclins. Chromomycin A2 treated cells depicted several cellular fragments resembling autophagosomes and increased expression of proteins LC3-A and LC3-B. Moreover, exposure to chromomycin A2 also induced the appearance of acidic vacuolar organelles in treated cells. These features combined are suggestive of the induction of autophagy promoted by chromomycin A2, a feature not previously described for chromomycins.

  16. Induced pluripotent stem cells, from generation to application: review article

    Directory of Open Access Journals (Sweden)

    Sharif Moradi

    2014-11-01

    Full Text Available Embryonic stem cells are pluripotent stem cells which have the ability to indefinitely self-renew and differentiate into all differentiated cells of the body. Regarding their two main properties (unlimited self-renewal and multi-lineage differentiation, these cells have various biomedical applications in basic research and cell based therapy. Because the transplantation of differentiated cells that are derived from embryonic stem cells is allogenic, they face the problem of immune rejection following the transplantation of embryonic stem cell-derived cells into patients. In 2006, researchers from Japan reported the derivation of a new type of pluripotent stem cells which could overcome the problem of immune rejection that is associated with the application of embryonic stem cells. They designated these cells as induced pluripotent stem (iPS cells, because their production was ‘induced’ from differentiated somatic cells using a combination of four embryonic stem cell-associated transcription factors. Importantly, these pluripotent stem cells exhibit all the key features of embryonic stem cells including unlimited self-renewal and multi-lineage differentiation potential, and can pass the most stringent test of pluripotency which is known as the tetraploid (4n complementation. Hence, in addition to bypassing the problem of immune rejection, iPS cells have all of the potential applications of embryonic stem cells, including in developmental studies, toxicology research, drug discovery and disease modeling. Also, considering that they could be generated from patient’s own cells, iPS cells hold great promise in the future of patient-specific cell replacement therapies using pluripotent stem cells. In this review article, we will present a comprehensive review on the how and why of the generation of iPS cell from somatic cells of the body and discuss how they should be characterized in terms of morphologically, pluripotent stem cell behavior, and

  17. Expression of inducible nitric oxide in human lung epithelial cells.

    Science.gov (United States)

    Robbins, R A; Barnes, P J; Springall, D R; Warren, J B; Kwon, O J; Buttery, L D; Wilson, A J; Geller, D A; Polak, J M

    1994-08-30

    Nitric oxide (NO) is increased in the exhaled air of subjects with several airway disorders. To determine if cytokines could stimulate epithelial cells accounting for the increased NO, the capacity of the proinflammatory cytokines (cytomix: tumor necrosis factor-alpha, interleukin-1 beta, and interferon-gamma) to increase inducible nitric oxide synthase (iNOS) was investigated in A549 and primary cultures of human bronchial epithelial cells. Cytomix induced a time-dependent increase in nitrite levels in culture supernatant fluids (p < 0.05). Increased numbers of cells stained for iNOS and increased iNOS mRNA was detected in the cytokine-stimulated cells compared to control (p < 0.05). Dexamethasone diminished the cytokine-induced increase in nitrite, iNOS by immunocytochemistry, and iNOS mRNA. These data demonstrate that cytokines, such as those released by mononuclear cells, can induce lung epithelial iNOS expression and NO release, and that this is attenuated by dexamethasone.

  18. Bay Area Transit Agencies Propel Fuel Cell Buses Toward Commercialization (Fact Sheet)

    Energy Technology Data Exchange (ETDEWEB)

    2010-07-01

    This fact sheet describes the Zero Emission Bay Area (ZEBA) demonstration of the next generation of fuel cells buses. Several transit agencies in the San Francisco Bay Area are participating in demonstrating the largest single fleet of fuel cell buses in the United States.

  19. Analysis of light intensity dependence of organic photovoltaics: towards efficient large-area solar cells

    NARCIS (Netherlands)

    Galagan, Y.O.; Manor, A.; Andriessen, H.A.J.M.; Katz, E.A.

    2012-01-01

    Large-area organic solar cells are known to suffer from a major efficiency decrease which originates from the combination of a voltage drop across the front electrode and the voltage-dependent photocurrent. In this letter, we demonstrate this efficiency loss on large area, indium tin oxide free cell

  20. Neurospheres from rat adipose-derived stem cells could be induced into functional Schwann cell-like cells in vitro

    Directory of Open Access Journals (Sweden)

    Shan Yanchang

    2008-02-01

    Full Text Available Abstract Background Schwann cells (SC which are myelin-forming cells in peripheral nervous system are very useful for the treatment of diseases of peripheral nervous system and central nervous system. However, it is difficult to obtain sufficient large number of SC for clinical use, so alternative cell systems are desired. Results Using a procedure similar to the one used for propagation of neural stem cells, we could induce rat adipose-derived stem cells (ADSC into floating neurospheres. In addition to being able to differentiate into neuronal- and glial-like cells, neurospheres could be induced to differentiate into SC-like cells. SC-like cells were bi- or tri-polar in shape and immunopositive for nestin and SC markers p75, GFAP and S-100, identical to genuine SC. We also found that SC-like cells could induce the differentiation of SH-SY5Y neuroblastoma cells efficiently, perhaps through secretion of soluble substances. We showed further that SC-like cells could form myelin structures with PC12 cell neurites in vitro. Conclusion These findings indicated that ADSC could differentiate into SC-like cells in terms of morphology, phenotype and functional capacities. SC-like cells induced from ADSC may be useful for the treatment of neurological diseases.

  1. Oxidative Stress, Cell Death, and Other Damage to Alveolar Epithelial Cells Induced by Cigarette Smoke

    Directory of Open Access Journals (Sweden)

    Nagai A

    2003-09-01

    Full Text Available Abstract Cigarette smoking is a major risk factor in the development of various lung diseases, including pulmonary emphysema, pulmonary fibrosis, and lung cancer. The mechanisms of these diseases include alterations in alveolar epithelial cells, which are essential in the maintenance of normal alveolar architecture and function. Following cigarette smoking, alterations in alveolar epithelial cells induce an increase in epithelial permeability, a decrease in surfactant production, the inappropriate production of inflammatory cytokines and growth factors, and an increased risk of lung cancer. However, the most deleterious effect of cigarette smoke on alveolar epithelial cells is cell death, i.e., either apoptosis or necrosis depending on the magnitude of cigarette smoke exposure. Cell death induced by cigarette smoke exposure can largely be accounted for by an enhancement in oxidative stress. In fact, cigarette smoke contains and generates many reactive oxygen species that damage alveolar epithelial cells. Whether apoptosis and/or necrosis in alveolar epithelial cells is enhanced in healthy cigarette smokers is presently unclear. However, recent evidence indicates that the apoptosis of alveolar epithelial cells and alveolar endothelial cells is involved in the pathogenesis of pulmonary emphysema, an important cigarette smoke-induced lung disease characterized by the loss of alveolar structures. This review will discuss oxidative stress, cell death, and other damage to alveolar epithelial cells induced by cigarette smoke.

  2. Sphingosine kinase-1 mediates androgen-induced osteoblast cell growth

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Claire [CNRS, Institut de Pharmacologie et de Biologie Structurale, Toulouse F-31000 (France); Universite de Toulouse, UPS, IPBS, Toulouse F-31000 (France); Lafosse, Jean-Michel [CHU Toulouse, Hopital Rangueil, Service d' orthopedie et Traumatologie, Toulouse F-31000 (France); Malavaud, Bernard [CNRS, Institut de Pharmacologie et de Biologie Structurale, Toulouse F-31000 (France); Universite de Toulouse, UPS, IPBS, Toulouse F-31000 (France); CHU Toulouse, Hopital Rangueil, Service d' Urologie et de Transplantation Renale, Toulouse F-31000 (France); Cuvillier, Olivier, E-mail: olivier.cuvillier@ipbs.fr [CNRS, Institut de Pharmacologie et de Biologie Structurale, Toulouse F-31000 (France); Universite de Toulouse, UPS, IPBS, Toulouse F-31000 (France)

    2010-01-01

    Herein we report that the lipid kinase sphingosine kinase-1 (SphK1) is instrumental in mediating androgen-induced cell proliferation in osteoblasts. Dihydrotestosterone (DHT) triggered cell growth in steroid-deprived MC3T3 cells, which was associated with a rapid stimulation of SphK1 and activation of both Akt and ERK signaling pathways. This mechanism relied on functional androgen receptor/PI3K/Akt nongenotropic signaling as pharmacological antagonists could block SphK1 stimulation by DHT and its consequences. Finally, SphK1 inhibition not only abrogated DHT-induced ERK activation but also blocked cell proliferation, while ERK inhibition had no impact, suggesting that SphK1 was critical for DHT signaling yet independently of the ERK.

  3. Cationic Conjugated Polymers-Induced Quorum Sensing of Bacteria Cells.

    Science.gov (United States)

    Zhang, Pengbo; Lu, Huan; Chen, Hui; Zhang, Jiangyan; Liu, Libing; Lv, Fengting; Wang, Shu

    2016-03-15

    Bacteria quorum sensing (QS) has attracted significant interest for understanding cell-cell communication and regulating biological functions. In this work, we demonstrate that water-soluble cationic conjugated polymers (PFP-G2) can interact with bacteria to form aggregates through electrostatic interactions. With bacteria coated in the aggregate, PFP-G2 can induce the bacteria QS system and prolong the time duration of QS signal molecules (autoinducer-2 (AI-2)) production. The prolonged AI-2 can bind with specific protein and continuously regulate downstream gene expression. Consequently, the bacteria show a higher survival rate against antibiotics, resulting in decreased antimicrobial susceptibility. Also, AI-2 induced by PFP-G2 can stimulate 55.54 ± 12.03% more biofilm in E. coli. This method can be used to understand cell-cell communication and regulate biological functions, such as the production of signaling molecules, antibiotics, other microbial metabolites, and even virulence.

  4. Radiation-induced cisplatin resistance in two human cell lines

    Energy Technology Data Exchange (ETDEWEB)

    Eichholtz-Wirth, H.; Stotzer, O. [GSF-Institute of Radiobiology and Cytometry, Neuherberg (Germany); Marx, K. [Medical Clin. III, University, Munich (Germany)

    1997-03-01

    Cisplatin resistance has been induced in human HT-29 and HeLa cells after low-dose fractionated {gamma}-irradiation. The drug resistance is modest and does not confer cross-resistance to irradiation. Alterations that were recently shown to correlate with radiation-induced cisplatin resistance in murine cells are not involved in the resistant HeLa-C3 cells. Scavengers, such as GSH or metallothioneins are unchanged and there is no alteration of the cGMP transduction pathway. Preliminary results in HeLa-C3 cells indicate that resistance is associated with differences of the apoptotic pathway, with enhancement of the p53 suppressor protein after cisplatin treatment but unchanged bcl-2 protein expression. (authors)

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

    Directory of Open Access Journals (Sweden)

    Ewelina Szliszka

    2009-12-01

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

  6. Mechanism of T-oligo-induced cell cycle arrest in Mia-Paca pancreatic cancer cells

    Science.gov (United States)

    Rankin, Andrew M.; Sarkar, Sibaji; Faller, Douglas V.

    2011-01-01

    DNA oligonucleotides with sequence homology to human telomeric DNA (T-oligo) induce cell cycle arrest, followed by apoptosis, senescence, or autophagy in a human cancer cell type-specific manner. T-oligo has potential as a new therapeutic strategy in oncology because of its ability to target certain types of tumor cells while sparing normal ones. In the present study, we demonstrate the T-oligo-induced S-phase cell cycle arrest in four pancreatic cancer cell lines. To further contribute to the mechanistic understanding of T-oligo, we also identify cyclin dependent kinase 2 (cdk2) as a functional mediator in the T-oligo-induced cell cycle arrest of pancreatic cancer cells. Ectopic expression of a constitutively-active cdk2 mutant abrogates T-oligo-induced cell cycle arrest in these tumor cells while knockdown of cdk2 expression alone recapitulates the T-oligo effect. Finally, we demonstrate the dispensability of T-oligo-induced ATM/ATR-mediated DNA damage response-signaling pathways, which have long been considered functional in the T-oligo signaling mechanism. PMID:21898405

  7. The calcimimetic R-568 induces apoptotic cell death in prostate cancer cells

    Directory of Open Access Journals (Sweden)

    Cheng Guangming

    2009-07-01

    Full Text Available Abstract Background Increased serum level of parathyroid hormone (PTH was found in metastatic prostate cancers. Calcimimetic R-568 was reported to reduce PTH expression, to suppress cell proliferation and to induce apoptosis in parathyroid cells. In this study, we investigated the effect of R-568 on cellular survival of prostate cancer cells. Methods Prostate cancer cell lines LNCaP and PC-3 were used in this study. Cellular survival was determined with MTT, trypan blue exclusion and fluorescent Live/Death assays. Western blot assay was utilized to assess apoptotic events induced by R-568 treatment. JC-1 staining was used to evaluate mitochondrial membrane potential. Results In cultured prostate cancer LNCaP and PC-3 cells, R-568 treatment significantly reduced cellular survival in a dose- and time-dependent manner. R-568-induced cell death was an apoptotic event, as evidenced by caspase-3 processing and PARP cleavage, as well as JC-1 color change in mitochondria. Knocking down calcium sensing receptor (CaSR significantly reduced R-568-induced cytotoxicity. Enforced expression of Bcl-xL gene abolished R-568-induced cell death, while loss of Bcl-xL expression led to increased cell death in R-568-treated LNCaP cells,. Conclusion Taken together, our data demonstrated that calcimimetic R-568 triggers an intrinsic mitochondria-related apoptotic pathway, which is dependent on the CaSR and is modulated by Bcl-xL anti-apoptotic pathway.

  8. Current progress and prospects of induced pluripotent stem cells

    Institute of Scientific and Technical Information of China (English)

    CHEN LingYi; Liu Lin

    2009-01-01

    Induced pluripotent stem (iPS) cells are derived from somatic cells by ectopic expression of few transcription factors. Like embryonic stem (ES) cells, iPS cells are able to self-renew indefinitely and to differentiate into all types of cells in the body. iPS cells hold great promise for regenerative medicine,because iPS ceils circumvent not only immunological rejection but also ethical issues. Since the first report on the derivation of iPS cells in 2006, many laboratories all over the world started research on iPS cells and have made significant progress. This paper reviews recent progress in iPS cell research,Including the methods to generate iPS cells, the molecular mechanism of reprogramming in the formation of iPS ceils, and the potential applications of iPS cells in cell replacement therapy. Current problems that need to be addressed and the prospects for iPS research are also discussed.

  9. Induced pluripotent stem cells:origins, applications, and future perspectives

    Institute of Scientific and Technical Information of China (English)

    Jing ZHAO; Wen-jie JIANG; Chen SUN; Cong-zhe HOU; Xiao-mei YANG; Jian-gang GAO

    2013-01-01

    Embryonic stem (ES) cells are widely used for different purposes, including gene targeting, celltherapy, tissue repair, organ regeneration, and so on. However, studies and applications of ES cells are hindered by ethical issues regarding cellsources. To circumvent ethical disputes, great efforts have been taken to generate ES cel-like cells, which are not derived from the inner cellmass of blastocyst-stage embryos. In 2006, Yamanaka et al. first re-programmed mouse embryonic fibroblasts into ES cell-like cells cal ed induced pluripotent stem (iPS) cells. About one year later, Yamanaka et al. and Thomson et al. independently reprogrammed human somatic cells into iPS cells. Since the first generation of iPS cells, they have now been derived from quite a few different kinds of celltypes. In particular, the use of peripheral blood facilitates research on iPS cells because of safety, easy availability, and plenty of cellsources. Now iPS cells have been used for celltherapy, disease modeling, and drug discovery. In this review, we describe the generations, applications, potential issues, and future perspectives of iPS cells.

  10. The tricyclic antidepressant imipramine induces autophagic cell death in U-87MG glioma cells.

    Science.gov (United States)

    Jeon, Seung-Hyun; Kim, Se Hyun; Kim, Yeni; Kim, Yong Sik; Lim, Yoongho; Lee, Young Han; Shin, Soon Young

    2011-09-23

    In this study, we investigated the antitumor effects of the tricyclic antidepressant 3-(10,11-dihydro-5H-dibenzo[b,f]azepin-5-yl)-N,N-dimethylpropan-1-amine (imipramine) on glioma cells. We found that exposure of U-87MG cells to imipramine resulted in the inhibition of PI3K/Akt/mTOR signaling, reduction of clonogenicity, and induction of cell death. Imipramine stimulated the formation of acidic vesicular organelles, the conversion of LC3-I to LC3-II, and the redistribution of LC3 to autophagosomes, suggesting that it stimulates the progression of autophagy. It did not, however, induce apoptosis. We further showed that knockdown of Beclin-1 using siRNA abrogated imipramine-induced cell death. These results suggest that imipramine exerts antitumor effects on PTEN-null U-87MG human glioma cells by inhibiting PI3K/Akt/mTOR signaling and by inducing autophagic cell death.

  11. [Establishment of hemophilia A patient-specific inducible pluripotent stem cells with urine cells].

    Science.gov (United States)

    Hu, Zhiqing; Hu, Xuyun; Pang, Jialun; Wang, Xiaolin; Lin Peng, Siyuan; Li, Zhuo; Wu, Yong; Wu, Lingqian; Liang, Desheng

    2015-10-01

    OBJECTIVE To generate hemophilia A (HA) patient-specific inducible pluripotent stem cells (iPSCs) and induce endothelial differentiation. METHODS Tubular epithelial cells were isolated and cultured from the urine of HA patients. The iPSCs were generated by forced expression of Yamanaka factors (Oct4, Sox2, c-Myc and Klf4) using retroviruses and characterized by cell morphology, pluripotent marker staining and in vivo differentiation through teratoma formation. Induced endothelial differentiation of the iPSCs was achieved with the OP9 cell co-culture method. RESULTS Patient-specific iPSCs were generated from urine cells of the HA patients, which could be identified by cell morphology, pluripotent stem cell surface marker staining and in vivo differentiation of three germ layers. The teratoma experiment has confirmed that such cells could differentiate into endothelial cells expressing the endothelial-specific markers CD144, CD31 and vWF. CONCLUSION HA patient-specific iPSCs could be generated from urine cells and can differentiate into endothelial cells. This has provided a new HA disease modeling approach and may serve as an applicable autologous cell source for gene correction and cell therapy studies for HA.

  12. Shear stress-induced improvement of red blood cell deformability

    OpenAIRE

    Meram, Ece; Yılmaz, Bahar D.; Bas, Ceren; Atac, Nazlı; Yalçın, Ö.; Başkurt, Oguz K.; Meiselman, Herbert J.

    2013-01-01

    Classically, it is known that red blood cell (RBC) deformability is determined by the geometric and material properties of these cells. Experimental evidence accumulated during the last decade has introduced the concept of active regulation of RBC deformability. This regulation is mainly related to altered associations between membrane skeletal proteins and integral proteins, with the latter serving to anchor the skeleton to the lipid matrix. It has been hypothesized that shear stress induces...

  13. Cathepsin G, a Neutrophil Protease, Induces Compact Cell-Cell Adhesion in MCF-7 Human Breast Cancer Cells

    Directory of Open Access Journals (Sweden)

    Tomoya Kudo

    2009-01-01

    Full Text Available Cathepsin G is a serine protease secreted by activated neutrophils that play a role in the inflammatory response. Because neutrophils are known to be invading leukocytes in various tumors, their products may influence the characteristics of tumor cells such as the growth state, motility, and the adhesiveness between cells or the extracellular matrix. Here, we demonstrate that cathepsin G induces cell-cell adhesion of MCF-7 human breast cancer cells resulting from the contact inhibition of cell movement on fibronectin but not on type IV collagen. Cathepsin G subsequently induced cell condensation, a very compact cell colony, resulting due to the increased strength of E-cadherin-mediated cell-cell adhesion. Cathepsin G action is protease activity-dependent and was inhibited by the presence of serine protease inhibitors. Cathepsin G promotes E-cadherin/catenin complex formation and Rap1 activation in MCF-7 cells, which reportedly regulates E-cadherin-based cell-cell junctions. Cathepsin G also promotes E-cadherin/protein kinase D1 (PKD1 complex formation, and Go6976, the selective PKD1 inhibitor, suppressed the cathepsin G-induced cell condensation. Our findings provide the first evidence that cathepsin G regulates E-cadherin function, suggesting that cathepsin G has a novel modulatory role against tumor cell-cell adhesion.

  14. Generation of Pig Induced Pluripotent Stem Cells with a Drug-Inducible System

    Institute of Scientific and Technical Information of China (English)

    Zhao Wu; Jijun Chen; Jiangtao Ren; Lei Bao; Jing Liao; Chun Cui; Linjun Rao; Hui Li; Yijun Gu; Huiming Dai; Hui Zhu; Xiaokun Teng; Lu Cheng; Lei Xiao

    2009-01-01

    Domesticated ungulate pluripotent embryonic stem (ES) cell lines would be useful for generating precise gene-modified animals. To date, many efforts have been made to establish domesticated ungulate pluripotent ES cells from early embryos without success.Here, we report the generation of porcine-induced pluripotent stem (iPS) cells using drug-inducible expression of defined factors.We showed that porcine iPS cells expressed alkaline phosphatase, SSEA3, SSEA4, Tra-1-60, Tra-1-81, Oct3/4, Nanog, Sox2, Rex1 and CDH1. Pig iPS cells expressed high levels of telomerase activity and showed normal karyotypes. These cells could differentiate into cell types of all three germ layers in vitro and in teratomas. Our study reveals properties of porcine pluripotent stem cells that may facilitate the eventual establishment of porcine ES cells. Moreover, the porcine iPS cells produced may be directly useful for the generation of precise gene-modified pigs.

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

    DEFF Research Database (Denmark)

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

    1998-01-01

    PURPOSE: The immune privilege of the eye has been thought to be dependent on physical barriers and absence of lymphatic vessels. However, the immune privilege may also involve active immunologic processes, as recent studies have indicated. The purpose of the present study was to investigate whether...... human retinal pigment epithelial (RPE) cells can induce apoptosis in activated T cells. METHODS: Fas ligand (FasL) expression was detected by flow cytometry and immunohistochemistry. Cultured RPE cells were cocultured with T-cell lines and peripheral blood lymphocytes for 6 hours to 2 days. Induction...... of apoptosis was detected by 7-amino-actinomycin D and annexin V staining. RESULTS: Retinal pigment epithelial cells expressed FasL and induced apoptosis in activated Fas+ T cells. Blocking of Fas-FasL interaction with antibody strongly inhibited RPE-mediated T-cell apoptosis. Retinal pigment epithelial cells...

  16. Catalase inhibits ionizing radiation-induced apoptosis in hematopoietic stem and progenitor cells.

    Science.gov (United States)

    Xiao, Xia; Luo, Hongmei; Vanek, Kenneth N; LaRue, Amanda C; Schulte, Bradley A; Wang, Gavin Y

    2015-06-01

    Hematologic toxicity is a major cause of mortality in radiation emergency scenarios and a primary side effect concern in patients undergoing chemo-radiotherapy. Therefore, there is a critical need for the development of novel and more effective approaches to manage this side effect. Catalase is a potent antioxidant enzyme that coverts hydrogen peroxide into hydrogen and water. In this study, we evaluated the efficacy of catalase as a protectant against ionizing radiation (IR)-induced toxicity in hematopoietic stem and progenitor cells (HSPCs). The results revealed that catalase treatment markedly inhibits IR-induced apoptosis in murine hematopoietic stem cells and hematopoietic progenitor cells. Subsequent colony-forming cell and cobble-stone area-forming cell assays showed that catalase-treated HSPCs can not only survive irradiation-induced apoptosis but also have higher clonogenic capacity, compared with vehicle-treated cells. Moreover, transplantation of catalase-treated irradiated HSPCs results in high levels of multi-lineage and long-term engraftments, whereas vehicle-treated irradiated HSPCs exhibit very limited hematopoiesis reconstituting capacity. Mechanistically, catalase treatment attenuates IR-induced DNA double-strand breaks and inhibits reactive oxygen species. Unexpectedly, we found that the radioprotective effect of catalase is associated with activation of the signal transducer and activator of transcription 3 (STAT3) signaling pathway and pharmacological inhibition of STAT3 abolishes the protective activity of catalase, suggesting that catalase may protect HSPCs against IR-induced toxicity via promoting STAT3 activation. Collectively, these results demonstrate a previously unrecognized mechanism by which catalase inhibits IR-induced DNA damage and apoptosis in HSPCs.

  17. Lysophosphatidate induces chemo-resistance by releasing breast cancer cells from taxol-induced mitotic arrest.

    Directory of Open Access Journals (Sweden)

    Nasser Samadi

    Full Text Available BACKGROUND: Taxol is a microtubule stabilizing agent that arrests cells in mitosis leading to cell death. Taxol is widely used to treat breast cancer, but resistance occurs in 25-69% of patients and it is vital to understand how Taxol resistance develops to improve chemotherapy. The effects of chemotherapeutic agents are overcome by survival signals that cancer cells receive. We focused our studies on autotaxin, which is a secreted protein that increases tumor growth, aggressiveness, angiogenesis and metastasis. We discovered that autotaxin strongly antagonizes the Taxol-induced killing of breast cancer and melanoma cells by converting the abundant extra-cellular lipid, lysophosphatidylcholine, into lysophosphatidate. This lipid stimulates specific G-protein coupled receptors that activate survival signals. METHODOLOGY/PRINCIPAL FINDINGS: In this study we determined the basis of these antagonistic actions of lysophosphatidate towards Taxol-induced G2/M arrest and cell death using cultured breast cancer cells. Lysophosphatidate does not antagonize Taxol action in MCF-7 cells by increasing Taxol metabolism or its expulsion through multi-drug resistance transporters. Lysophosphatidate does not lower the percentage of cells accumulating in G2/M by decreasing exit from S-phase or selective stimulation of cell death in G2/M. Instead, LPA had an unexpected and remarkable action in enabling MCF-7 and MDA-MB-468 cells, which had been arrested in G2/M by Taxol, to normalize spindle structure and divide, thus avoiding cell death. This action involves displacement of Taxol from the tubulin polymer fraction, which based on inhibitor studies, depends on activation of LPA receptors and phosphatidylinositol 3-kinase. CONCLUSIONS/SIGNIFICANCE: This work demonstrates a previously unknown consequence of lysophosphatidate action that explains why autotaxin and lysophosphatidate protect against Taxol-induced cell death and promote resistance to the action of this

  18. Embryonic stem cell-derived microvesicles induce gene expression changes in Muller cells of the retina.

    Directory of Open Access Journals (Sweden)

    Diana Katsman

    Full Text Available Cell-derived microvesicles (MVs, recognized as important components of cell-cell communication, contain mRNAs, miRNAs, proteins and lipids and transfer their bioactive contents from parent cells to cells of other origins. We have studied the effect that MVs released from embryonic stem cells (ESMVs have on retinal progenitor Müller cells. Cultured human Müller cells were exposed to mouse ESMVs every 48 hours for a total of 9 treatments. Morphological changes were observed by light microscopy in the treated cells, which grew as individual heterogeneous cells, compared to the uniform, spindle-like adherent cellular sheets of untreated cells. ESMVs transferred to Müller cells embryonic stem cell (ESC mRNAs involved in the maintenance of pluripotency, including Oct4 and Sox2, and the miRNAs of the 290 cluster, important regulators of the ESC-specific cell cycle. Moreover, ESMV exposure induced up-regulation of the basal levels of endogenous human Oct4 mRNA in Müller cells. mRNA and miRNA microarrays of ESMV-treated vs. untreated Müller cells revealed the up-regulation of genes and miRNAs involved in the induction of pluripotency, cellular proliferation, early ocular genes and genes important for retinal protection and remodeling, as well as the down-regulation of inhibitory and scar-related genes and miRNAs involved in differentiation and cell cycle arrest. To further characterize the heterogeneous cell population of ESMV-treated Müller cells, their expression of retinal cell markers was compared to that in untreated control cells by immunocytochemistry. Markers for amacrine, ganglion and rod photoreceptors were present in treated but not in control Müller cells. Together, our findings indicate that ESMs induce de-differentiation and pluripotency in their target Müller cells, which may turn on an early retinogenic program of differentiation.

  19. Performance model for large area solid oxide fuel cells

    Science.gov (United States)

    Klotz, Dino; Schmidt, Jan Philipp; Weber, André; Ivers-Tiffée, Ellen

    2014-08-01

    A parameter set obtained from a 1 cm2 size electrode cell is used to develop and calibrate a one-dimensional spatially resolved model. It is demonstrated that this performance model precalculates the evolving operating parameters along the gas channel of a large-sized cell. Input parameters are: (i) number of discretization elements N, accounting for anodic gas conversion, (ii) anodic gas flow rate and composition and (iv) operating voltage. The model calculations based on data from the 1 cm2 cell are scaled to be equivalent to a larger cell with 16 cm2 electrode size which is used to validate the performance model. The current/voltage characteristics can be predicted very accurately, even when anodic gas flow rates vary by as much as a factor of four. The performance model presented herein simulates the total overvoltage and does so in a broad range of operation conditions. This is done with an accuracy of the simulated current better than 6.1% for UOP = 0.85 V, 3.8% for UOP = 0.8 V and 3.7% for UOP = 0.75 V. It is hoped that these equations will form the basis of a greater model, capable of predicting all the conditions found throughout any industrial stack.

  20. Late steps of parvoviral infection induce changes in cell morphology.

    Science.gov (United States)

    Pakkanen, Kirsi; Nykky, Jonna; Vuento, Matti

    2008-11-01

    Previously, virus-induced non-filopodial extensions have not been encountered in connection with viral infections. Here, we report emergence of long extensions protruding from Norden laboratory feline kidney (NLFK) and A72 (canine fibroma) cells infected with canine parvovirus for 72 h. These extensions significantly differ in length and number from those appearing in control cells. The most striking feature in the extensions is the length, reaching up to 130 microm, almost twice the average length of a healthy NLFK cell. In A72 cells, the extensions were even longer, up to 200 microm. The results presented here also suggest that the events leading to the growth of these extensions start earlier in infection and abnormal extension growth is detectable already at 24-h post-infection (p.i.). These extensions may have a vital role in the cell-to-cell transmission of the virus.

  1. Interferon-inducible GTPases in cell autonomous and innate immunity.

    Science.gov (United States)

    Meunier, Etienne; Broz, Petr

    2016-02-01

    Detection and clearance of invading pathogens requires a coordinated response of the adaptive and innate immune system. Host cell, however, also features different mechanisms that restrict pathogen replication in a cell-intrinsic manner, collectively referred to as cell-autonomous immunity. In immune cells, the ability to unleash those mechanisms strongly depends on the activation state of the cell, which is controlled by cytokines or the detection of pathogen-associated molecular patterns by pattern-recognition receptors. The interferon (IFN) class of cytokines is one of the strongest inducers of antimicrobial effector mechanisms and acts against viral, bacterial and parasitic intracellular pathogens. This has been linked to the upregulation of several hundreds of IFN-stimulated genes, among them the so-called IFN-inducible GTPases. Two subfamilies of IFN-inducible GTPases, the immunity-related GTPases (IRGs) and the guanylate-binding proteins (GBPs), have gained attention due to their exceptional ability to specifically target intracellular vacuolar pathogens and restrict their replication by destroying their vacuolar compartment. Their repertoire has recently been expanded to the regulation of inflammasome complexes, which are cytosolic multi-protein complexes that control an inflammatory cell death called pyroptosis and the release of cytokines like interleukin-1β and interleukin-18. Here we discuss recent advances in understanding the function, the targeting and regulation of IRG and GBP proteins during microbial infections.

  2. Resveratrol induces apoptosis in human esophageal carcinoma cells

    Institute of Scientific and Technical Information of China (English)

    Hai-Bo Zhou; Yun Yan; Ya-Ni Sun; Ju-Ren Zhu

    2003-01-01

    AIM: To investigate the apoptosis in esophageal cancer cells induced by resveratrol, and the relation between this apoptosis and expression of Bcl-2 and Bax.METHODS: In in vitro experiments, MTr assay was used to determine the cell growth inhibitory rate. Transmission electron microscope and TUNEL staining method were used to quantitatively and qualitively detect the apoptosis status of esophageal cancer cell line EC-9706 before and after the resveratrol treatment. Immunohistochemical staining was used to detect the expression of apoptosis-regulated gene Bcl-2 and Bax.RESULTS: Resveratrol inhibited the growth of esophageal cancer cell line EC-9706 in a dose-and time-dependent manner. Resveratrol induced EC-9706 cells to undergo apoptosis with typically apoptotic characteristics, including morphological changes of chromatin condensation, chromatin crescent formation, nucleus fragmentation and apoptotic body formation. TUNEL assay showed that after the for 24 to 96 hours, the AIs were apparently increased with treated time (P<0.05). Immunohistochemical staining showed that after the treatment of EC-9706 cells with proteins were apparently reduced with treated time (P<0.05)and the PRs of Bax proteins were apparently increased with treated time (P<0.05).CONCLUSION: Resveratrol is able to induce the apoptosisin esophageal cancer. This apoptosis may be mediated by down-regulating the apoptosis-regulated gene Bcl-2 and upregulating the expression of apoptosis-regulated gene bax.

  3. Bile-acid-induced cell injury and protection

    Institute of Scientific and Technical Information of China (English)

    Maria J Perez; Oscar Briz

    2009-01-01

    Several studies have characterized the cellular and molecular mechanisms of hepatocyte injury caused by the retention of hydrophobic bile acids (BAs) in cholestatic diseases. BAs may disrupt cell membranes through their detergent action on lipid components and can promote the generation of reactive oxygen species that, in turn, oxidatively modify lipids, proteins, and nucleic acids, and eventually cause hepatocyte necrosis and apoptosis. Several pathways are involved in triggering hepatocyte apoptosis. Toxic BAs can activate hepatocyte death receptors directly and induce oxidative damage, thereby causing mitochondrial dysfunction, and induce endoplasmic reticulum stress. When these compounds are taken up and accumulate inside biliary cells, they can also cause apoptosis. Regarding extrahepatic tissues, the accumulation of BAs in the systemic circulation may contribute to endothelial injury in the kidney and lungs. In gastrointestinal cells, BAs may behave as cancer promoters through an indirect mechanism involving oxidative stress and DNA damage, as well as acting as selection agents for apoptosis-resistant cells. The accumulation of BAs may have also deleterious effects on placental and fetal cells. However, other BAs, such as ursodeoxycholic acid, have been shown to modulate BA-induced injury in hepatocytes. The major beneficial effects of treatment with ursodeoxycholic acid are protection against cytotoxicity due to more toxic BAs; the stimulation of hepatobiliary secretion; antioxidant activity, due in part to an enhancement in glutathione levels; and the inhibition of liver cell apoptosis. Other natural BAs or their derivatives, such as cholyl-Nmethylglycine or cholylsarcosine, have also aroused pharmacological interest owing to their protective properties.

  4. Idelalisib induces PUMA-dependent apoptosis in colon cancer cells.

    Science.gov (United States)

    Yang, Shida; Zhu, Zhiyong; Zhang, Xiaobing; Zhang, Ning; Yao, Zhicheng

    2017-01-24

    Idelalisib, a PI3K inhibitor, specifically targeting p110δ, has been approved for the treatment of chronic lymphocytic leukemia/small lymphocytic lymphoma and follicular lymphoma. However, the mechanisms of action of idelalisib in colon cancer cells are not well understood. We investigated how idelalisib suppresses colon cancer cells growth and potentiates effects of other chemotherapeutic drugs. In this study, we found that idelalisib treatment induces PUMA in colon cancer cells irrespective of p53 status through the p65 pathway following AKT inhibition and glycogen synthase kinase 3β (GSK3β) activation. PUMA is necessary for idelalisib-induced apoptosis in colon cancer cells. Idelalisib also synergized with 5-FU or regorafenib to induce marked apoptosis via PUMA in colon cancer cells. Furthermore, PUMA deficiency suppressed apoptosis and antitumor effect of idelalisib in xenograft model. These results demonstrate a critical role of PUMA in mediating the anticancer effects of idelalisib in colon cancer cells and suggest that PUMA induction can be used as an indicator of idelalisib sensitivity, and also have important implications for it clinical applications.

  5. Cytoprotective effects of fisetin against hypoxia-induced cell death in PC12 cells.

    Science.gov (United States)

    Chen, Pei-Yi; Ho, Yi-Ru; Wu, Ming-Jiuan; Huang, Shun-Ping; Chen, Po-Kong; Tai, Mi-Hsueh; Ho, Chi-Tang; Yen, Jui-Hung

    2015-01-01

    Fisetin (3,7,3',4'-tetrahydroxyflavone), a flavonol compound of flavonoids, exhibits a broad spectrum of biological activities including anti-oxidant, anti-inflammatory, anti-cancer and neuroprotective effects. The aim of this study is to investigate the cytoprotective effect of fisetin and the underlying molecular mechanism against hypoxia-induced cell death in PC12 cells. The results of this study showed that fisetin significantly restored the cell viability of PC12 cells under both cobalt chloride (CoCl₂)- and low oxygen-induced hypoxic conditions. Treatment with fisetin successfully reduced the CoCl₂-mediated reactive oxygen species (ROS) production, which was accompanied by an increase in the cell viability of PC12 cells. Furthermore, we found that treatment of PC12 cells with fisetin markedly upregulated hypoxia-inducible factor 1α (HIF-1α), its nuclear accumulation and the hypoxia-response element (HRE)-driven transcriptional activation. The fisetin-mediated cytoprotection during CoCl₂ exposure was significantly attenuated through the administration of HIF-1α siRNA. Moreover, we demonstrated that MAPK/ERK kinase 1/2 (MEK1/2), p38 MAPK and phosphatidylinositol 3-kinase (PI3 K) inhibitors significantly blocked the increase in cell survival that was induced by fisetin treatment under hypoxic conditions. Consistently, increased phosphorylation of ERK, p38 and Akt proteins was observed in PC12 cells treated with fisetin. However, the fisetin-induced HRE-driven transcription was not affected by inhibition of these kinase signaling pathways. Current results reveal for the first time that fisetin promotes cell survival and protects against hypoxia-induced cell death through ROS scavenging and the activation of HIF1α-, MAPK/ERK-, p38 MAPK- and PI3 K/Akt-dependent signaling pathways in PC12 cells.

  6. Generation of colonies of induced trophoblast cells during standard reprogramming of porcine fibroblasts to induced pluripotent stem cells.

    Science.gov (United States)

    Ezashi, Toshihiko; Matsuyama, Haruyo; Telugu, Bhanu Prakash V L; Roberts, R Michael

    2011-10-01

    During reprogramming of porcine mesenchymal cells with a four-factor (POU5F1/SOX2/KLF4/MYC) mixture of vectors, a fraction of the colonies had an atypical phenotype and arose earlier than the recognizable porcine induced pluripotent stem (iPS) cell colonies. Within days after each passage, patches of cells with an epithelial phenotype formed raised domes, particularly under 20% O(2) conditions. Relative to gene expression of the iPS cells, there was up-regulation of genes for transcription factors associated with trophoblast (TR) lineage emergence, e.g., GATA2, PPARG, MSX2, DLX3, HAND1, GCM1, CDX2, ID2, ELF5, TCFAP2C, and TEAD4 and for genes required for synthesis of products more typical of differentiated TR, such as steroids (HSD17B1, CYP11A1, and STAR), pregnancy-associated glycoproteins (PAG6), and select cytokines (IFND, IFNG, and IL1B). Although POU5F1 was down-regulated relative to that in iPS cells, it was not silenced in the induced TR (iTR) cells over continued passage. Like iPS cells, iTR cells did not senesce on extended passage and displayed high telomerase activity. Upon xenografting into immunodeficient mice, iTR cells formed nonhemorrhagic teratomas composed largely of layers of epithelium expressing TR markers. When cultured under conditions that promoted embryoid body formation, iTR cells formed floating spheres consisting of a single epithelial sheet whose cells were tethered laterally by desmosome-like structures. In conclusion, reprogramming of porcine fibroblasts to iPS cells generates, as a by-product, colonies composed of self-renewing populations of TR cells, possibly containing TR stem cells.

  7. Characterization of T-regulatory cells, induced by immature dendritic cells, which inhibit enteroantigen-reactive colitis-inducing T-cell responses in vitro and in vivo

    DEFF Research Database (Denmark)

    Gad, Monika; Kristensen, Nanna N; Kury, Evelyn

    2004-01-01

    -injected into severe combined immunodeficiency (SCID) mice with colitis-inducing CD4(+) CD25(-) T cells. Both unfractionated CD4(+) and purified CD25(+) Treg cells fully protected the recipients against the development of colitis. In contrast, co-transfer of fractionated CD25(-) T cells offered no protection against...

  8. Cell transplantation therapies for spinal cord injury focusing on induced pluripotent stem cells

    Institute of Scientific and Technical Information of China (English)

    Masaya Nakamura; Hideyuki Okano

    2013-01-01

    Stimulated by the 2012 Nobel Prize in Physiology or Medicine awarded for Shinya Yamanaka and Sir John Gurdon,there is an increasing interest in the induced pluripotent stem (iPS) cells and reprograming technologies in medical science.While iPS cells are expected to open a new era providing enormous opportunities in biomedical sciences in terms of cell therapies and regenerative medicine,safety-related concerns for iPS cell-based cell therapy should be resolved prior to the clinical application of iPS cells.In this review,the pre-clinical investigations of cell therapy for spinal cord injury (SCI) using neural stem/progenitor cells derived from iPS cells,and their safety issues in vivo,are outlined.We also wish to discuss the strategy for the first human trails of iPS cell-based cell therapy for SCI patients.

  9. Cell transplantation therapies for spinal cord injury focusing on induced pluripotent stem cells.

    Science.gov (United States)

    Nakamura, Masaya; Okano, Hideyuki

    2013-01-01

    Stimulated by the 2012 Nobel Prize in Physiology or Medicine awarded for Shinya Yamanaka and Sir John Gurdon, there is an increasing interest in the induced pluripotent stem (iPS) cells and reprograming technologies in medical science. While iPS cells are expected to open a new era providing enormous opportunities in biomedical sciences in terms of cell therapies and regenerative medicine, safety-related concerns for iPS cell-based cell therapy should be resolved prior to the clinical application of iPS cells. In this review, the pre-clinical investigations of cell therapy for spinal cord injury (SCI) using neural stem/progenitor cells derived from iPS cells, and their safety issues in vivo, are outlined. We also wish to discuss the strategy for the first human trails of iPS cell-based cell therapy for SCI patients.

  10. Investigation of Hepatoprotective Activity of Induced Pluripotent Stem Cells in the Mouse Model of Liver Injury

    Directory of Open Access Journals (Sweden)

    Chih-Hung Chiang

    2011-01-01

    Full Text Available To date liver transplantation is the only effective treatment for end-stage liver diseases. Considering the potential of pluripotency and differentiation into tridermal lineages, induced pluripotent stem cells (iPSCs may serve as an alternative of cell-based therapy. Herein, we investigated the effect of iPSC transplantation on thioacetamide- (TAA- induced acute/fulminant hepatic failure (AHF in mice. Firstly, we demonstrated that iPSCs had the capacity to differentiate into hepatocyte-like cells (iPSC-Heps that expressed various hepatic markers, including albumin, α-fetoprotein, and hepatocyte nuclear factor-3β, and exhibited biological functions. Intravenous transplantation of iPSCs effectively reduced the hepatic necrotic area, improved liver functions and motor activity, and rescued TAA-treated mice from lethal AHF. 1,1′-dioctadecyl-3,3,3′,3′-tetramethylindocarbocyanine perchlorate cell labeling revealed that iPSCs potentially mobilized to the damaged liver area. Taken together, iPSCs can effectively rescue experimental AHF and represent a potentially favorable cell source of cell-based therapy.

  11. Ecabet sodium alleviates neomycin-induced hair cell damage.

    Science.gov (United States)

    Rah, Yoon Chan; Choi, June; Yoo, Myung Hoon; Yum, Gunhwee; Park, Saemi; Oh, Kyoung Ho; Lee, Seung Hoon; Kwon, Soon Young; Cho, Seung Hyun; Kim, Suhyun; Park, Hae-Chul

    2015-12-01

    Ecabet sodium (ES) is currently applied to some clinical gastrointestinal disease primarily by the inhibition of the ROS production. In this study, the protective role of ES was evaluated against the neomycin-induced hair cell loss using zebrafish experimental animal model. Zebrafish larvae (5-7 dpf), were treated with each of the following concentrations of ES: 5, 10, 20, 40, and 80 μg/mL for 1 h, followed by 125 μM neomycin for 1h. The positive control group was established by 125 μM neomycin-only treatment (1h) and the negative control group with no additional chemicals was also established. Hair cells inside four neuromasts ( SO1, SO2, O1, OC1) were assessed using fluorescence microscopy (n = 10). Hair cell survival was calculated as the mean number of viable hair cells for each group. Apoptosis and mitochondrial damage were investigated using special staining (TUNEL and DASPEI assay, respectively), and compared among groups. Ultrastructural changes were evaluated using scanning electron microscopy. Pre-treatment group with ES increased the mean number of viable hair cells as a dose-dependent manner achieving almost same number of viable hair cells with 40 μM/ml ES treatment (12.98 ± 2.59 cells) comparing to that of the negative control group (14.15 ± 1.39 cells, p = 0.72) and significantly more number of viable hair cells than that of the positive control group (7.45 ± 0.91 cells, p neomycin treatment than the negative control group and significantly decreased down to 105% with the pre-treatment with 40 μM/ml ES (n = 40, p = 0.04). A significantly less number of TUNEL-positive cells (reflecting apoptosis, p neomycin-induced hair cell loss possibly by reducing apoptosis, mitochondrial damages, and the ROS generation.

  12. HIV-1 induces DCIR expression in CD4+ T cells.

    Directory of Open Access Journals (Sweden)

    Alexandra A Lambert

    Full Text Available The C-type lectin receptor DCIR, which has been shown very recently to act as an attachment factor for HIV-1 in dendritic cells, is expressed predominantly on antigen-presenting cells. However, this concept was recently challenged by the discovery that DCIR can also be detected in CD4(+ T cells found in the synovial tissue from rheumatoid arthritis (RA patients. Given that RA and HIV-1 infections share common features such as a chronic inflammatory condition and polyclonal immune hyperactivation status, we hypothesized that HIV-1 could promote DCIR expression in CD4(+ T cells. We report here that HIV-1 drives DCIR expression in human primary CD4(+ T cells isolated from patients (from both aviremic/treated and viremic/treatment naive persons and cells acutely infected in vitro (seen in both virus-infected and uninfected cells. Soluble factors produced by virus-infected cells are responsible for the noticed DCIR up-regulation on uninfected cells. Infection studies with Vpr- or Nef-deleted viruses revealed that these two viral genes are not contributing to the mechanism of DCIR induction that is seen following acute infection of CD4(+ T cells with HIV-1. Moreover, we report that DCIR is linked to caspase-dependent (induced by a mitochondria-mediated generation of free radicals and -independent intrinsic apoptotic pathways (involving the death effector AIF. Finally, we demonstrate that the higher surface expression of DCIR in CD4(+ T cells is accompanied by an enhancement of virus attachment/entry, replication and transfer. This study shows for the first time that HIV-1 induces DCIR membrane expression in CD4(+ T cells, a process that might promote virus dissemination throughout the infected organism.

  13. Potential of cardiac stem/progenitor cells and induced pluripotent stem cells for cardiac repair in ischaemic heart disease

    OpenAIRE

    Wang, Wei Eric; Chen, Xiongwen; Houser, Steven R.; Zeng, Chunyu

    2013-01-01

    Stem cell therapy has emerged as a promising strategy for cardiac and vascular repair. The ultimate goal is to rebuild functional myocardium by transplanting exogenous stem cells or by activating native stem cells to induce endogenous repair. CS/PCs (cardiac stem/progenitor cells) are one type of adult stem cell with the potential to differentiate into cardiac lineages (cardiomyocytes, smooth muscle cells and endothelial cells). iPSCs (induced pluripotent stem cells) also ha...

  14. Quercetin-Induced Cell Death in Human Papillary Thyroid Cancer (B-CPAP Cells

    Directory of Open Access Journals (Sweden)

    Ergül Mutlu Altundağ

    2016-01-01

    Full Text Available In this study, we have investigated the antiproliferative effect of quercetin on human papillary thyroid cancer cells and determined the apoptotic mechanisms underlying its actions. We have used different concentrations of quercetin to induce apoptosis and measured cell viability. Apoptosis and cell cycle analysis was determined by flow cytometry using Annexin V and propidium iodide. Finally, we have measured changes in caspase-3 and cleaved poly(ADP-ribose polymerase (PARP protein expression levels as hallmarks of apoptosis and Hsp90 protein expression level as a marker of proteasome activity in treated and control cells. Quercetin treatment of human papillary thyroid cancer cells resulted in decreased cell proliferation and increased rate of apoptosis by caspase activation. Furthermore, it was demonstrated that quercetin induces cancer cell apoptosis by downregulating the levels of Hsp90. In conclusion, we have shown that quercetin induces downregulation of Hsp90 expression that may be involved in the decrease of chymotrypsin-like proteasome activity which, in order, induces inhibition of growth and causes cell death in thyroid cancer cells. Thus, quercetin appears to be a promising candidate drug for Hsp90 downregulation and apoptosis of thyroid cancer cells.

  15. Generation of human-induced pluripotent stem cells.

    Science.gov (United States)

    Park, In-Hyun; Lerou, Paul H; Zhao, Rui; Huo, Hongguang; Daley, George Q

    2008-01-01

    Pluripotent cells, such as embryonic stem cells, are invaluable tools for research and can potentially serve as a source of cell- and tissue-replacement therapy. Rejection after transplantation of cells and tissue derived from embryonic stem cells is a significant obstacle to their clinical use. Recently, human somatic cells have been reprogrammed directly to pluripotency by ectopic expression of four transcription factors (Oct4, Sox2, Klf4 and Myc) to yield induced pluripotent stem (iPS) cells. Human iPS cells are a potential source of patient-specific pluripotent stem cells that would bypass immune rejection. iPS cells can also be used to study diseases for which there are no adequate human in vitro or animal models. In this protocol, we describe how to establish primary human fibroblasts lines and how to derive iPS cells by retroviral transduction of reprogramming factors. Overall, it takes 2 months to complete reprogramming human primary fibroblasts starting from biopsy.

  16. PTPN2 attenuates T-cell lymphopenia-induced proliferation

    Science.gov (United States)

    Wiede, Florian; La Gruta, Nicole L.; Tiganis, Tony

    2014-01-01

    When the peripheral T-cell pool is depleted, T cells undergo homoeostatic expansion. This expansion is reliant on the recognition of self-antigens and/or cytokines, in particular interleukin-7. The T cell-intrinsic mechanisms that prevent excessive homoeostatic T-cell responses and consequent overt autoreactivity remain poorly defined. Here we show that protein tyrosine phosphatase N2 (PTPN2) is elevated in naive T cells leaving the thymus to restrict homoeostatic T-cell proliferation and prevent excess responses to self-antigens in the periphery. PTPN2-deficient CD8+ T cells undergo rapid lymphopenia-induced proliferation (LIP) when transferred into lymphopenic hosts and acquire the characteristics of antigen-experienced effector T cells. The enhanced LIP is attributed to elevated T-cell receptor-dependent, but not interleukin-7-dependent responses, results in a skewed T-cell receptor repertoire and the development of autoimmunity. Our results identify a major mechanism by which homoeostatic T-cell responses are tuned to prevent the development of autoimmune and inflammatory disorders.

  17. Endothelin-1 induces a histamine-dependent flare in vivo, but does not activate human skin mast cells in vitro.

    OpenAIRE

    Brain, S D; Thomas, G.; Crossman, D.C.; Fuller, R.; Church, M. K.

    1992-01-01

    The role of the mast cell in endothelin-1 induced flare has been investigated by in vivo and in vitro experiments. The intradermal injection of endothelin-1 (10 pmol) into human skin induced a pallor with surrounding axon-reflex flare which is similar to the flare response to histamine (1 nmol). At these doses, chosen to give identical flare areas, blood flow was increased in the area of the endothelin-induced flare over a longer period. A systemic H1-receptor antagonist significantly inhibit...

  18. The fungicide mancozeb induces toxic effects on mammalian granulosa cells

    Energy Technology Data Exchange (ETDEWEB)

    Paro, Rita [Department of Health Sciences, University of L' Aquila, Via Vetoio, L' Aquila (Italy); Tiboni, Gian Mario [Department of Medicine and Aging, Section of Reproductive Sciences, University “G. D' Annunzio”, Chieti-Pescara (Italy); Buccione, Roberto [Tumor Cell Invasion Laboratory, Consorzio Mario Negri Sud, Santa Maria Imbaro, Chieti (Italy); Rossi, Gianna; Cellini, Valerio [Department of Health Sciences, University of L' Aquila, Via Vetoio, L' Aquila (Italy); Canipari, Rita [Department of Anatomy, Histology, Forensic Medicine and Orthopedics, Section of Histology and Embryology, School of Pharmacy and Medicine, “Sapienza” University of Rome, Rome (Italy); Cecconi, Sandra, E-mail: sandra.cecconi@cc.univaq.it [Department of Health Sciences, University of L' Aquila, Via Vetoio, L' Aquila (Italy)

    2012-04-15

    The ethylene-bis-dithiocarbamate mancozeb is a widely used fungicide with low reported toxicity in mammals. In mice, mancozeb induces embryo apoptosis, affects oocyte meiotic spindle morphology and impairs fertilization rate even when used at very low concentrations. We evaluated the toxic effects of mancozeb on the mouse and human ovarian somatic granulosa cells. We examined parameters such as cell morphology, induction of apoptosis, and p53 expression levels. Mouse granulosa cells exposed to mancozeb underwent a time- and dose-dependent modification of their morphology, and acquired the ability to migrate but not to proliferate. The expression level of p53, in terms of mRNA and protein content, decreased significantly in comparison with unexposed cells, but no change in apoptosis was recorded. Toxic effects could be attributed, at least in part, to the presence of ethylenthiourea (ETU), the main mancozeb catabolite, which was found in culture medium. Human granulosa cells also showed dose-dependent morphological changes and reduced p53 expression levels after exposure to mancozeb. Altogether, these results indicate that mancozeb affects the somatic cells of the mammalian ovarian follicles by inducing a premalignant-like status, and that such damage occurs to the same extent in both mouse and human GC. These results further substantiate the concept that mancozeb should be regarded as a reproductive toxicant. Highlights: ► The fungicide mancozeb affects oocyte spindle morphology and fertilization rate. ► We investigated the toxic effects of mancozeb on mouse and human granulosa cells. ► Granulosa cells modify their morphology and expression level of p53. ► Mancozeb induces a premalignant-like status in exposed cells.

  19. Apoptosis of human primary gastric carcinoma cells induced by genistein

    Institute of Scientific and Technical Information of China (English)

    Hai-Bo Zhou; Juan-Juan Chen; Wen-Xia Wang; Jian-Ting Cai; Qin Du

    2004-01-01

    AIM: To investigate the apoptosis in primary gastric cancer cells induced by genistein, and the relationship between this apoptosis and expression of bcl-2 and bax.METHODS: MTT assay was used to determine the cell growth inhibitory rate in vitro. Transmission electron microscope and TUNEL staining were used to quantitatively and qualitatively detect the apoptosis of primary gastric cancer cells before and after genistein treatment. Immunohistochemical staining and RT-PCR were used to detect the expression of apoptosisassociated genes bcl-2 and bax.RESULTS: Genistein inhibited the growth of primary gastric cancer cells in dose-and time-dependent manner. Genistein induced primary gastric cancer cells to undergo apoptosis with typically apoptotic characteristics. TUNEL assay showed that after the treatment of primary gastric cancer cells with genistein for 24 to 96 h, the apoptotic rates of primary gastric cancer cells increased time-dependently. Immunohistochemical staining showed that after the treatment of primary gastric cancer cells with genistein for 24 to 96 h, the positivity rates of Bcl-2 proteins were apparently reduced with time and the positivity rates of Bax proteins were apparently increased with time. After exposed to genistein at 20 μmol/L for 24,48, 72 and 96 respectively, the density of bcl-2 mRNA decreased progressively and the density of bax mRNA increased progressively with elongation of time.CONCLUSION: Genistein is able to induce the apoptosis in primary gastric cancer cells. This apoptosis may be mediated by down-regulating the apoptosis- associated bcl-2 gene and up-regulating the expression of apoptosis-associated bax gene.

  20. Signatures of nonlinearity in single cell noise-induced oscillations

    NARCIS (Netherlands)

    Thomas, P.; Straube, A.V.; Timmer, J.; Fleck, C.; Grima, R.

    2013-01-01

    A class of theoretical models seeks to explain rhythmic single cell data by postulating that they are generated by intrinsic noise in biochemical systems whose deterministic models exhibit only damped oscillations. The main features of such noise-induced oscillations are quantified by the power spec

  1. Mastoparan-Induced Cell Death Signalling in Chlamydomonas Reinhardtii

    NARCIS (Netherlands)

    Yordanova, Z.P.; Kapchina-Toteva, V.M.; Woltering, E.J.; Cristescu, S.M.; Harren, F.J.M.; Yakimova, E.T.

    2009-01-01

    The present study was focused on the elucidation of stress-induced cell death signaling events in the unicellular alga Chlamydomonas reinhardtii exposed to treatment with wasp venom mastoparan. By applying pharmacological approach with specific inhibitors, we have investigated the involvement of eth

  2. Inducible resistance to Fas—mediated apoptosis in B cells

    Institute of Scientific and Technical Information of China (English)

    ROTHSTEINTHOMASL

    2000-01-01

    Apoptosis produced in B cells through Fas(APO-1,CD95) triggering is regulated by signals derived from other surface receptors:CD40 engagement produces upregulation of Fas expression and marked susceptibility to Fas-induced cell death,whereas antigen receptor engagement,or IL-4R engagement,inhibits Fas killing and in so doing induces a state of Fas-resistance,even in otherwise sensitive,CD40-stimulated targets.Surface immunoglobulin and IL-4R utilize at least partially distinct path ways to produce Fas-resistance that differentially depend on PKC and STAT6,respectively.Further,surface immunoglobulin signaling for inducible Fas-resistance bypasses Btk,requires NF-κB,and entails new macromolecular synthesis.Terminal effectors of B cell Fas-resistance include the known anti-apoptotic gene products,Bcl-XL and FLIP,and a novel anti-apoptotic gene that encodes FAIM (Fas Apoptosis Inhibitory Molecule).faim was identified by differential display and exists in two alternatively spliced forms;faim-S is broadly expressed,but faim-L expression is tissue-specific.The FAIM sequence is highly evolu tionarily conserved,suggesting an important role for this molecule throughout phylogeny.Inducible resistance to Fas killing is hypothesized to protect foreign antigen-specific B cells during potentially hazardous interactions with FasL-bearing T cells,whereas autoreactive B cells fail to become Fas-resistant and are deleted via Fas-dependent cytotoxicity.Inadvertent or aberrant acquisition of Fas-resistance may permit autoreactive B cells to escape Fas deletion,and malignant lymphocytes to impede anti-tumor immunity.

  3. Inducible resistance to Fas-mediated apoptosis in B cells

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Apoptosis produced in B cells through Fas (APO-1, CD95) triggering is regulated by signals derived from other surface receptors: CD40 engagement produces upregulation of Fas expression and marked susceptibility to Fas-induced cell death, whereas antigen receptor engagement, or IL-4R engagement, inhibits Fas killing and in so doing induces a state of Fas-resistance, even in otherwise sensitive, CD40-stimulated targets. Surface immunoglobulin and IL-4R utilize at least partially distinct pathways to produce Fas-resistance that differentially depend on PKC and STAT6, respectively. Further, surface immunoglobulin signaling for inducible Fas-resistance bypasses Btk, requires NF-кB, and entails new macromolecular synthesis. Terminal effectors of B cell Fas-resistance include the known anti-apoptotic gene products, Bcl-xL and FLIP, and a novel anti-apoptotic gene that encodes FAIM (Fas Apoptosis Inhibitory Molecule). faim was identified by differential display and exists in two alternatively spliced forms; faim-S is broadly expressed, but faim-L expression is tissue-specific. The FAIM sequence is highly evolutionarily conserved, suggesting an important role for this molecule throughout phylogeny. Inducible resistance to Fas killing is hypothesized to protect foreign antigen-specific B cells during potentially hazardous interactions with FasL-bearing T cells, whereas autoreactive B cells fail to become Fas-resistant and are deleted via Fas-dependent cytotoxicity. Inadvertent or aberrant acquisition of Fas-resistance may permit autoreactive B cells to escape Fas deletion, and malignant lymphocytes to impede anti-tumor immunity.

  4. Mercury induces inflammatory mediator release from human mast cells

    Directory of Open Access Journals (Sweden)

    Peterson Erika

    2010-03-01

    Full Text Available Abstract Background Mercury is known to be neurotoxic, but its effects on the immune system are less well known. Mast cells are involved in allergic reactions, but also in innate and acquired immunity, as well as in inflammation. Many patients with Autism Spectrum Disorders (ASD have "allergic" symptoms; moreover, the prevalence of ASD in patients with mastocytosis, characterized by numerous hyperactive mast cells in most tissues, is 10-fold higher than the general population suggesting mast cell involvement. We, therefore, investigated the effect of mercuric chloride (HgCl2 on human mast cell activation. Methods Human leukemic cultured LAD2 mast cells and normal human umbilical cord blood-derived cultured mast cells (hCBMCs were stimulated by HgCl2 (0.1-10 μM for either 10 min for beta-hexosaminidase release or 24 hr for measuring vascular endothelial growth factor (VEGF and IL-6 release by ELISA. Results HgCl2 induced a 2-fold increase in β-hexosaminidase release, and also significant VEGF release at 0.1 and 1 μM (311 ± 32 pg/106 cells and 443 ± 143 pg/106 cells, respectively from LAD2 mast cells compared to control cells (227 ± 17 pg/106 cells, n = 5, p 2 (0.1 μM to the proinflammatory neuropeptide substance P (SP, 0.1 μM had synergestic action in inducing VEGF from LAD2 mast cells. HgCl2 also stimulated significant VEGF release (360 ± 100 pg/106 cells at 1 μM, n = 5, p 6 cells, and IL-6 release (466 ± 57 pg/106 cells at 0.1 μM compared to untreated cells (13 ± 25 pg/106 cells, n = 5, p 2 (0.1 μM to SP (5 μM further increased IL-6 release. Conclusions HgCl2 stimulates VEGF and IL-6 release from human mast cells. This phenomenon could disrupt the blood-brain-barrier and permit brain inflammation. As a result, the findings of the present study provide a biological mechanism for how low levels of mercury may contribute to ASD pathogenesis.

  5. Cupressus lusitanica (Cupressaceae) leaf extract induces apoptosis in cancer cells.

    Science.gov (United States)

    Lopéz, L; Villavicencio, M A; Albores, A; Martínez, M; de la Garza, J; Meléndez-Zajgla, J; Maldonado, V

    2002-05-01

    A crude ethanolic extract of Cupressus lusitanica Mill. leaves demonstrate cytotoxicity in a panel of cancer cell lines. Cell death was due to apoptosis, as assessed by morphologic features (chromatin condensation and apoptotic bodies formation) and specific DNA fragmentation detected by in situ end-labeling of DNA breaks (TUNEL). The apoptotic cell death was induced timely in a dose-dependent manner. Despite the absence of changes in the expression levels of antiapoptotic protein Bcl-2, proapoptotic Bax protein variants omega and delta were increased. These results warrant further research of possible antitumor compounds in this plant.

  6. Monocyte cell surface glycosaminoglycans positively modulate IL-4-induced differentiation toward dendritic cells.

    NARCIS (Netherlands)

    Dekker, E. den; Grefte, S.; Huijs, T.; Dam, G.B. ten; Versteeg, E.M.M.; Berk, L.C.J. van den; Bladergroen, B.A.; Kuppevelt, A.H.M.S.M. van; Figdor, C.G.; Torensma, R.

    2008-01-01

    IL-4 induces the differentiation of monocytes toward dendritic cells (DCs). The activity of many cytokines is modulated by glycosaminoglycans (GAGs). In this study, we explored the effect of GAGs on the IL-4-induced differentiation of monocytes toward DCs. IL-4 dose-dependently up-regulated the expr

  7. Induced pluripotent stem (iPS) cells from human fetal stem cells.

    Science.gov (United States)

    Guillot, Pascale V

    2016-02-01

    Pluripotency defines the ability of stem cells to differentiate into all the lineages of the three germ layers and self-renew indefinitely. Somatic cells can regain the developmental potential of embryonic stem cells following ectopic expression of a set of transcription factors or, in certain circumstances, via modulation of culture conditions and supplementation with small molecule, that is, induced pluripotent stem (iPS) cells. Here, we discuss the use of fetal tissues for reprogramming, focusing in particular on stem cells derived from human amniotic fluid, and the development of chemical reprogramming. We next address the advantages and disadvantages of deriving pluripotent cells from fetal tissues and the potential clinical applications.

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

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

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

  9. [Ribonuclease binase induces death in T-cell acute lymphoblastic leukemia cells by apoptosis].

    Science.gov (United States)

    Burnysheva, K M; Petrushanko, I Yu; Spirin, P V; Prassolov, V S; Makarov, A A; Mitkevich, V A

    2016-01-01

    Bacterial ribonuclease binase is a potential anticancer agent. In the present study, we have determined the toxic effect of binase towards cell lines of T-cell acute lymphoblastic leukemia Jurkat and CEMss. We have shown that binase induces apoptosis in these cells. At the same time, binase does not cause toxic effects in leukocytes of healthy donors, which suggests that binase activity towards leukemic cells is selective. We have found that the treatment of cancer cells with binase leads to a reduction in reactive oxygen species and transcription factor NFκB levels, and demonstrated that these effects are a common feature of the action of RNases on cancer cells.

  10. Induced pluripotent stem cells: Challenges and opportunities for cancer immunotherapy

    Directory of Open Access Journals (Sweden)

    Patty eSachamitr

    2014-04-01

    Full Text Available Despite recent advances in cancer treatment over the past 30 years, therapeutic options remain limited and do not always offer a cure for malignancy. Given that tumour associated antigens (TAA are, by definition, self-proteins, the need to productively engage autoreactive T cells remains at the heart of strategies for cancer immunotherapy. These have traditionally focussed on the administration of autologous monocyte-derived dendritic cells (moDC pulsed with TAA, or the ex vivo expansion and adoptive transfer of tumour infiltrating lymphocytes (TIL as a source of TAA-specific cytotoxic T cells (CTL. Although such approaches have shown some efficacy, success has been limited by the poor capacity of moDC to cross-present exogenous TAA to the CD8+ T cell repertoire and the potential for exhaustion of CTL expanded ex vivo. Recent advances in induced pluripotency offer opportunities to generate patient-specific stem cell lines with the potential to differentiate in vitro into cell types whose properties may help address these issues. Here we review recent success in the differentiation of NK cells from human induced pluripotent stem (iPS cells as well as minor subsets of DC with therapeutic potential, including CD141+XCR1+ DC, capable of cross-presenting TAA to naïve CD8+ T cells. Furthermore, we review recent progress in the use of TIL as the starting material for the derivation of iPSC lines, thereby capturing their antigen specificity in a self-renewing stem cell line, from which potentially unlimited numbers of naïve TAA-specific T cells may be differentiated, free of the risks of exhaustion.

  11. A large area position-sensitive ionization chamber for heavy-ion-induced reaction studies

    CERN Document Server

    Pant, L M; Dinesh, B V; Thomas, R G; Saxena, A; Sawant, Y S; Choudhury, R K

    2002-01-01

    A large area position-sensitive ionization chamber with a wide dynamic range has been developed to measure the mass, charge and energy of the heavy ions and the fission fragments produced in heavy-ion-induced reactions. The split anode geometry of the detector makes it suitable for both particle identification and energy measurements for heavy ions and fission fragments. The detector has been tested with alpha particles from sup 2 sup 4 sup 1 Am- sup 2 sup 3 sup 9 Pu source, fission fragments from sup 2 sup 5 sup 2 Cf and the heavy-ion beams from the 14UD Mumbai Pelletron accelerator facility. Using this detector, measurements on mass and total kinetic energy distributions in heavy-ion-induced fusion-fission reactions have been carried out for a wide range of excitation energies. Results on deep inelastic collisions and mass-energy correlations on different systems using this detector setup are discussed.

  12. Data on the role of accessible surface area on osmolytes-induced protein stabilization

    Directory of Open Access Journals (Sweden)

    Safikur Rahman

    2017-02-01

    Full Text Available This paper describes data related to the research article “Testing the dependence of stabilizing effect of osmolytes on the fractional increase in the accessible surface area on thermal and chemical denaturations of proteins” [1]. Heat- and guanidinium chloride (GdmCl-induced denaturation of three disulfide free proteins (bovine cytochrome c (b-cyt-c, myoglobin (Mb and barstar in the presence of different concentrations of methylamines (sarcosine, glycine-betaine (GB and trimethylamine-N-oxide (TMAO was monitored by [ϴ]222, the mean residue ellipticity at 222 nm at pH 7.0. Methylamines belong to a class of osmolytes known to protect proteins from deleterious effect of urea. This paper includes comprehensive thermodynamic data obtained from the heat- and GdmCl-induced denaturations of barstar, b-cyt-c and Mb.

  13. A large area position-sensitive ionization chamber for heavy-ion-induced reaction studies

    Energy Technology Data Exchange (ETDEWEB)

    Pant, L.M. E-mail: lalit.pant@exp2.physik.uni-giessen.de; Biswas, D.C.; Dinesh, B.V.; Thomas, R.G.; Saxena, A.; Sawant, Y.S.; Choudhury, R.K

    2002-12-11

    A large area position-sensitive ionization chamber with a wide dynamic range has been developed to measure the mass, charge and energy of the heavy ions and the fission fragments produced in heavy-ion-induced reactions. The split anode geometry of the detector makes it suitable for both particle identification and energy measurements for heavy ions and fission fragments. The detector has been tested with {alpha} particles from {sup 241}Am-{sup 239}Pu source, fission fragments from {sup 252}Cf and the heavy-ion beams from the 14UD Mumbai Pelletron accelerator facility. Using this detector, measurements on mass and total kinetic energy distributions in heavy-ion-induced fusion-fission reactions have been carried out for a wide range of excitation energies. Results on deep inelastic collisions and mass-energy correlations on different systems using this detector setup are discussed.

  14. Cytoplasmic p21 induced by p65 prevents doxorubicin-induced cell death in pancreatic carcinoma cell line

    Directory of Open Access Journals (Sweden)

    Zhou YingQi

    2012-02-01

    Full Text Available Abstract Background Studies have shown the existence of p21 induction in a p53-dependent and -independent pathway. Our previous study indicates that DOX-induced p65 is able to bind the p21 promoter to activate its transactivation in the cells. Methods Over-expression and knock-down experiments were performed in Human Pancreatic Carcinoma (PANC1 cells. Cell cycle and cell death related proteins were assessed by Western Blotting. Cytotoxicity assay was checked by CCK-8 kit. Cell growth was analyzed by flow cytometers. Results Here we showed that over-expression of p65 decreased the cytotoxic effect of DOX on PANC1 cells, correlating with increased induction of cytoplasmic p21. We observed that pro-caspase-3 physically associated with cytoplasmic p21, which may be contribution to prevent p21 translocation into the nucleus. Our data also suggested that no clear elevation of nuclear p21 by p65 provides a survival advantage by progression cell cycle after treatment of DOX. Likewise, down-regulation of p65 expression enhanced the cytotoxic effect of DOX, due to a significant decrease of mRNA levels of anti-apoptotic genes, such as the cellular inhibitor of apoptosis-1 (c-IAP1, and the long isoform of B cell leukemia/lymphoma-2 (Bcl-2, leading to efficient induction of caspase-3 cleavage in the cells. More, we present evidence that over-expression of p53 or p53/p65 in the PANC1 cells were more sensitive to DOX treatment, correlated with activation of caspase-3 and clear elevation of nuclear p21 level. Our previous data suggested that expression of p21 increases Gefitinib-induced cell death by blocking the cell cycle at the G1 and G2 phases. The present findings here reinforced this idea by showing p21's ability of potentiality of DOX-induced cell death correlated with its inhibition of cell cycle progression after over-expression of p53 or p53/p65. Conclusion Our data suggested p65 could increase p53-mediated cell death in response to DOX in PANC1 cells

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

    Science.gov (United States)

    Kwon, Min-Young; Park, Eunhee; Lee, Seon-Jin; Chung, Su Wol

    2015-09-15

    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.

  16. Uranium induces oxidative stress in lung epithelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Periyakaruppan, Adaikkappan; Kumar, Felix; Sarkar, Shubhashish; Sharma, Chidananda S.; Ramesh, Govindarajan T. [Texas Southern University, Molecular Neurotoxicology Laboratory/Proteomics Core, Department of Biology, Houston, TX (United States)

    2007-06-15

    Uranium compounds are widely used in the nuclear fuel cycle, antitank weapons, tank armor, and also as a pigment to color ceramics and glass. Effective management of waste uranium compounds is necessary to prevent exposure to avoid adverse health effects on the population. Health risks associated with uranium exposure includes kidney disease and respiratory disorders. In addition, several published results have shown uranium or depleted uranium causes DNA damage, mutagenicity, cancer and neurological defects. In the current study, uranium toxicity was evaluated in rat lung epithelial cells. The study shows uranium induces significant oxidative stress in rat lung epithelial cells followed by concomitant decrease in the antioxidant potential of the cells. Treatment with uranium to rat lung epithelial cells also decreased cell proliferation after 72 h in culture. The decrease in cell proliferation was attributed to loss of total glutathione and superoxide dismutase in the presence of uranium. Thus the results indicate the ineffectiveness of antioxidant system's response to the oxidative stress induced by uranium in the cells. (orig.)

  17. Human amnion epithelial cells can be induced to differentiate into functional insulin-producing cells

    Institute of Scientific and Technical Information of China (English)

    Yanan Hou; Qin Huang; Tianjin Liu; Lihe Guo

    2008-01-01

    Pancreatic islet transplantation has demonstrated that long-term insulin independence may be achieved in patients suffering from diabetes mellitus type 1. However, limited availability of islet tissue means that new sources of insulinproducing cells that are responsive to glucose are required. Here, we show that human amnion epithelial cells (HAEC) can be induced to differentiate into functional insulinproducing cells in vitro. After induction of differentiation, HAEC expressed multiple pancreatic --cell genes, including insulin, pancreas duodenum homeobox-1, paired box gene 6,NK2 transcription factor-related locus 2, Islet 1, glucokinase,and glucose transporter-2, and released C-peptide in a glucose-regulated manner in response to other extracellular stimulations. The transplantation of induced HAEC into streptozotocin-induced diabetic C57 mice reversed hyperglycemia, restored body weight, and maintained euglycemia for 30 d. These findings indicated that HAEC may be a new source for cell replacement therapy in type 1 diabetes.

  18. Generating a non-integrating human induced pluripotent stem cell bank from urine-derived cells.

    Directory of Open Access Journals (Sweden)

    Yanting Xue

    Full Text Available Induced pluripotent stem cell (iPS cell holds great potential for applications in regenerative medicine, drug discovery, and disease modeling. We describe here a practical method to generate human iPS cells from urine-derived cells (UCs under feeder-free, virus-free, serum-free condition and without oncogene c-MYC. We showed that this approach could be applied in a large population with different genetic backgrounds. UCs are easily accessible and exhibit high reprogramming efficiency, offering advantages over other cell types used for the purpose of iPS generation. Using the approach described in this study, we have generated 93 iPS cell lines from 20 donors with diverse genetic backgrounds. The non-viral iPS cell bank with these cell lines provides a valuable resource for iPS cells research, facilitating future applications of human iPS cells.

  19. Clinical Studies Applying Cytokine-Induced Killer Cells for the Treatment of Renal Cell Carcinoma

    Directory of Open Access Journals (Sweden)

    Clara E. Jäkel

    2012-01-01

    Full Text Available Metastatic renal cell carcinoma (RCC seems to be resistant to conventional chemo- and radiotherapy and the general treatment regimen of cytokine therapy produces only modest responses while inducing severe side effects. Nowadays standard of care is the treatment with VEGF-inhibiting agents or mTOR inhibition; nevertheless, immunotherapy can induce complete remissions and long-term survival in selected patients. Among different adoptive lymphocyte therapies, cytokine-induced killer (CIK cells have a particularly advantageous profile as these cells are easily available, have a high proliferative rate, and exhibit a high antitumor activity. Here, we reviewed clinical studies applying CIK cells, either alone or with standard therapies, for the treatment of RCC. The adverse events in all studies were mild, transient, and easily controllable. In vitro studies revealed an increased antitumor activity of peripheral lymphocytes of participants after CIK cell treatment and CIK cell therapy was able to induce complete clinical responses in RCC patients. The combination of CIK cell therapy and standard therapy was superior to standard therapy alone. These studies suggest that CIK cell immunotherapy is a safe and competent treatment strategy for RCC patients and further studies should investigate different treatment combinations and schedules for optimal application of CIK cells.

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

    Energy Technology Data Exchange (ETDEWEB)

    Marrero, Maria Teresa; Estevez, Sara; Negrin, Gledy; Quintana, Jose [Departamento de Bioquimica, Unidad Asociada al Consejo Superior de Investigaciones Cientificas, Universidad de Las Palmas de Gran Canaria, Plaza Dr. Pasteur s/n, 35016 Las Palmas de Gran Canaria (Spain); Lopez, Mariana; Perez, Francisco J.; Triana, Jorge [Departamento de Quimica, Universidad de Las Palmas de Gran Canaria, Instituto Canario de Investigacion del Cancer, 35017 Las Palmas de Gran Canaria (Spain); Leon, Francisco [Instituto de Productos Naturales y Agrobiologia, Consejo Superior de Investigaciones Cientificas, Avda. Astrofisico F. Sanchez 3, 38206 La Laguna, Tenerife (Spain); Estevez, Francisco, E-mail: festevez@dbbf.ulpgc.es [Departamento de Bioquimica, Unidad Asociada al Consejo Superior de Investigaciones Cientificas, Universidad de Las Palmas de Gran Canaria, Plaza Dr. Pasteur s/n, 35016 Las Palmas de Gran Canaria (Spain)

    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.

  1. Streptococcus induces circulating CLA(+) memory T-cell-dependent epidermal cell activation in psoriasis.

    Science.gov (United States)

    Ferran, Marta; Galván, Ana B; Rincón, Catalina; Romeu, Ester R; Sacrista, Marc; Barboza, Erika; Giménez-Arnau, Ana; Celada, Antonio; Pujol, Ramon M; Santamaria-Babí, Luis F

    2013-04-01

    Streptococcal throat infection is associated with a specific variant of psoriasis and with HLA-Cw6 expression. In this study, activation of circulating psoriatic cutaneous lymphocyte-associated antigen (CLA)(+) memory T cells cultured together with epidermal cells occurred only when streptococcal throat extracts were added. This triggered the production of Th1, Th17, and Th22 cytokines, as well as epidermal cell mediators (CXCL8, CXCL9, CXCL10, and CXCL11). Streptococcal extracts (SEs) did not induce any activation with either CLA(-) cells or memory T cells cultured together with epidermal cells from healthy subjects. Intradermal injection of activated culture supernatants into mouse skin induced epidermal hyperplasia. SEs also induced activation when we used epidermal cells from nonlesional skin of psoriatic patients with CLA(+) memory T cells. Significant correlations were found between SE induced upregulation of mRNA expression for ifn-γ, il-17, il-22, ip-10, and serum level of antistreptolysin O in psoriatic patients. This study demonstrates the direct involvement of streptococcal infection in pathological mechanisms of psoriasis, such as IL-17 production and epidermal cell activation.

  2. Paclitaxel induces apoptosis in human gastric carcinoma cells

    Institute of Scientific and Technical Information of China (English)

    Hai-Bo Zhou; Ju-Ren Zhu

    2003-01-01

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

  3. Two endogenous proteins that induce cell wall extension in plants

    Science.gov (United States)

    McQueen-Mason, S.; Durachko, D. M.; Cosgrove, D. J.

    1992-01-01

    Plant cell enlargement is regulated by wall relaxation and yielding, which is thought to be catalyzed by elusive "wall-loosening" enzymes. By employing a reconstitution approach, we found that a crude protein extract from the cell walls of growing cucumber seedlings possessed the ability to induce the extension of isolated cell walls. This activity was restricted to the growing region of the stem and could induce the extension of isolated cell walls from various dicot stems and the leaves of amaryllidaceous monocots, but was less effective on grass coleoptile walls. Endogenous and reconstituted wall extension activities showed similar sensitivities to pH, metal ions, thiol reducing agents, proteases, and boiling in methanol or water. Sequential HPLC fractionation of the active wall extract revealed two proteins with molecular masses of 29 and 30 kD associated with the activity. Each protein, by itself, could induce wall extension without detectable hydrolytic breakdown of the wall. These proteins appear to mediate "acid growth" responses of isolated walls and may catalyze plant cell wall extension by a novel biochemical mechanism.

  4. Mortalin sensitizes human cancer cells to MKT-077-induced senescence.

    Science.gov (United States)

    Deocaris, Custer C; Widodo, Nashi; Shrestha, Bhupal G; Kaur, Kamaljit; Ohtaka, Manami; Yamasaki, Kazuhiko; Kaul, Sunil C; Wadhwa, Renu

    2007-07-18

    Mortalin is a chaperone protein that functions in many cellular processes such as mitochondrial biogenesis, intracellular trafficking, cell proliferation and signaling. Its upregulation in many human cancers makes it a candidate target for therapeutic intervention by small molecule drugs. In continuation to our earlier studies showing mortalin as a cellular target of MKT-077, a mitochondrion-seeking delocalized cationic dye that causes selective death of cancer cells, in this work, we report that MKT-077 binds to the nucleotide-binding domain of mortalin, causes tertiary structural changes in the protein, inactivates its chaperone function, and induces senescence in human tumor cell lines. Interestingly, in tumor cells with elevated level of mortalin expression, fairly low drug doses were sufficient to induce senescence. Guided by molecular screening for mortalin in tumor cells, our results led to the idea that working at low doses of the drug could be an alternative senescence-inducing cancer therapeutic strategy that could, in theory, avoid renal toxicities responsible for the abortion of MKT-077 clinical trials. Our work may likely translate to a re-appraisal of the therapeutic benefits of low doses of several classes of anti-tumor drugs, even of those that had been discontinued due to adverse effects.

  5. Heat Shock Protein 96 Induces Maturation of Dendritic Cells

    Institute of Scientific and Technical Information of China (English)

    Chunxia Cao; Wei Yang; Yonglie Chu; Qingguang Liu; Liang Yu; Cheng'en Pan

    2006-01-01

    Objective: Heat shock protein (HSP) has the promiscuous abilities to chaperone and present a broad repertoire of tumor antigens to antigen presenting cells including DCs. In this report, we analyzed the modulation of immature DC by HSP 96 (gp96).Method: Murine bone marrow-derived DC was induced by GM-CSF plus IL-4, which aped the immunostimulatory effects of DC.Cocultured DC and gp96-peptide complexes (gp96-PC) or inactivated H22 cells, the expression of MHC class Ⅱ, CD40, CD80 was quantified by flow cytometry. The concentration of IL-12 and TNF- in culture supernatants were determined by ELISA.[51] Cr release assay was used to test specific cytotoxic T cell. Results: Our study demonstrated that the extent of DC maturation induced by gp96-PC, which was reflected in surface density of costimulatory and MHC Ⅱ molecules, was correlated with the secretion of IL-12 and with the T cellactivating potential in vitro. Conclusion: Heat shock protein 96 could be isolated and purified from H22 cells and could induce maturation of dendritic cell. Our findings might be relevance to the use of DC vaccine in therapy of human tumors.

  6. Clostridium perfringens Delta-Toxin Induces Rapid Cell Necrosis.

    Directory of Open Access Journals (Sweden)

    Soshi Seike

    Full Text Available Clostridium perfringens delta-toxin is a β-pore-forming toxin and a putative pathogenic agent of C. perfringens types B and C. However, the mechanism of cytotoxicity of delta-toxin remains unclear. Here, we investigated the mechanisms of cell death induced by delta-toxin in five cell lines (A549, A431, MDCK, Vero, and Caco-2. All cell lines were susceptible to delta-toxin. The toxin caused rapid ATP depletion and swelling of the cells. Delta-toxin bound and formed oligomers predominantly in plasma membrane lipid rafts. Destruction of the lipid rafts with methyl β-cyclodextrin inhibited delta-toxin-induced cytotoxicity and ATP depletion. Delta-toxin caused the release of carboxyfluorescein from sphingomyelin-cholesterol liposomes and formed oligomers; toxin binding to the liposomes declined with decreasing cholesterol content in the liposomes. Flow cytometric assays with annexin V and propidium iodide revealed that delta-toxin treatment induced an elevation in the population of annexin V-negative and propidium iodide-positive cells. Delta-toxin did not cause the fragmentation of DNA or caspase-3 activation. Furthermore, delta-toxin caused damage to mitochondrial membrane permeability and cytochrome c release. In the present study, we demonstrate that delta-toxin produces cytotoxic activity through necrosis.

  7. Two-step differentiation of mast cells from induced pluripotent stem cells.

    Science.gov (United States)

    Yamaguchi, Tomoko; Tashiro, Katsuhisa; Tanaka, Satoshi; Katayama, Sumie; Ishida, Waka; Fukuda, Ken; Fukushima, Atsuki; Araki, Ryoko; Abe, Masumi; Mizuguchi, Hiroyuki; Kawabata, Kenji

    2013-03-01

    Mast cells play important roles in the pathogenesis of allergic diseases. They are generally classified into 2 phenotypically distinct populations: connective tissue-type mast cells (CTMCs) and mucosal-type mast cells (MMCs). The number of mast cells that can be obtained from tissues is limited, making it difficult to study the function of mast cells. Here, we report the generation and characterization of CTMC-like mast cells derived from mouse induced pluripotent stem (iPS) cells. iPS cell-derived mast cells (iPSMCs) were generated by the OP9 coculture method or embryoid body formation method. The number of Safranin O-positive cells, expression levels of CD81 protein and histidine decarboxylase mRNA, and protease activities were elevated in the iPSMCs differentiated by both methods as compared with those in bone marrow-derived mast cells (BMMCs). Electron microscopic analysis revealed that iPSMCs contained more granules than BMMCs. Degranulation was induced in iPSMCs after stimulation with cationic secretagogues or vancomycin. In addition, iPSMCs had the ability to respond to stimulation with the IgE/antigen complex in vitro and in vivo. Moreover, when iPSMCs generated on OP9 cells were cocultured with Swiss 3T3 fibroblasts, protease activities as maturation index were more elevated, demonstrating that mature mast cells were differentiated from iPS cells. iPSMCs can be used as an in vitro model of CTMCs to investigate their functions.

  8. Cholesterol induces proliferation of chicken primordial germ cells.

    Science.gov (United States)

    Chen, Dongyang; Chen, Meijuan; Lu, Zhenping; Yang, Mengmeng; Xie, Long; Zhang, Wenxin; Xu, Huiyan; Lu, Kehuan; Lu, Yangqing

    2016-08-01

    Primordial germ cells (PGCs) are the precursors of sperm and eggs and may serve as suitable cells for use in research in developmental biology and transgenic animals. However, the long-term propagation of PGCs in vitro has so far been plagued by the loss of their germ cell characteristics. This is largely because of the scarcity of knowledge concerning cell division and proliferation in these cells and the poor optimization of the culture medium. The sonic hedgehog (SHH) signaling pathway is involved in proliferation of many types of cells, but little is known about its role in chicken PGCs. The results of the current study indicate that the proliferation of chicken PGCs increases significantly when cholesterol, a molecule that facilitates the trafficking of HH ligands, is supplemented in the culture medium. This effect was attenuated when an SHH antagonist, cyclopamine was added, suggesting the involvement of SHH signaling in this process. The characterization of PGCs treated with cholesterol has shown that these cells express germ-cell-related markers and retain their capability to colonize the embryonic gonad after re-introduction to vasculature of stage-15 HH embryos, indicating that proliferation of PGCs induced by cholesterol does not alter the germ cell characteristics of these cells.

  9. Reprogramming fibroblasts into induced pluripotent stem cells with Bmi

    Institute of Scientific and Technical Information of China (English)

    Jai-Hee Moon; June Seok Heo; Jun Sung Kim; Eun Kyoung Jun; Jung Han Lee; Aeree Kim; Jonggun Kim

    2011-01-01

    Somatic cells can be reprogrammed into induced pluripotent stem (iPS) cells by the transcription factors Oct4,Sox2,and Klf4 in combination with c-Myc.Recently,Sox2 plus Oct4 was shown to reprogram fibroblasts and Oct4 alone was able to reprogram mouse and human neural stem cells (NSCs) into iPS cells.Here,we report that Bmi1 leads to the transdifferentiation of mouse fibroblasts into NSC-like cells,and,in combination with Oct4,can replace Sox2,Klf4 and c-Myc during the reprogramming of fibroblasts into iPS cells.Furthermore,activation of sonic hedgehog signaling (by Shh,purmorphamine,or oxysterol) compensates for the effects of Bmil,and,in combination with Oct4,reprograms mouse embryonic and adult fibroblasts into iPS cells.One- and two-factor iPS cells are similar to mouse embryonic stem cells in their global gene expression profile,epigenetic status,and in vitro and in vivo differentiation into all three germ layers,as well as teratoma formation and germline transmission in vivo.These data support that converting fibroblasts with Bmi1 or activation of the sonic hedgehog pathway to an intermediate cell type that expresses Sox2,KIf4,and N-Myc allows iPS generation via the addition of Oct4.

  10. Generation of human melanocytes from induced pluripotent stem cells.

    Directory of Open Access Journals (Sweden)

    Shigeki Ohta

    Full Text Available Epidermal melanocytes play an important role in protecting the skin from UV rays, and their functional impairment results in pigment disorders. Additionally, melanomas are considered to arise from mutations that accumulate in melanocyte stem cells. The mechanisms underlying melanocyte differentiation and the defining characteristics of melanocyte stem cells in humans are, however, largely unknown. In the present study, we set out to generate melanocytes from human iPS cells in vitro, leading to a preliminary investigation of the mechanisms of human melanocyte differentiation. We generated iPS cell lines from human dermal fibroblasts using the Yamanaka factors (SOX2, OCT3/4, and KLF4, with or without c-MYC. These iPS cell lines were subsequently used to form embryoid bodies (EBs and then differentiated into melanocytes via culture supplementation with Wnt3a, SCF, and ET-3. Seven weeks after inducing differentiation, pigmented cells expressing melanocyte markers such as MITF, tyrosinase, SILV, and TYRP1, were detected. Melanosomes were identified in these pigmented cells by electron microscopy, and global gene expression profiling of the pigmented cells showed a high similarity to that of human primary foreskin-derived melanocytes, suggesting the successful generation of melanocytes from iPS cells. This in vitro differentiation system should prove useful for understanding human melanocyte biology and revealing the mechanism of various pigment cell disorders, including melanoma.

  11. Effects of fracture contact areas on seismic attenuation due to wave-induced fluid flow

    Science.gov (United States)

    Germán Rubino, J.; Müller, Tobias M.; Milani, Marco; Holliger, Klaus

    2014-05-01

    Wave-induced fluid flow (WIFF) between fractures and the embedding matrix is considered to be a predominant seismic attenuation mechanism in fractured rocks. That is, due to the strong compressibility contrast between fractures and embedding matrix, seismic waves induce strong fluid pressure gradients, followed by local fluid flow between such regions, which in turn produces significant energy dissipation. Natural fractures can be conceptualized as two surfaces in partial contact, containing very soft and highly permeable material in the inner region. It is known that the characteristics of the fracture contact areas control the mechanical properties of the rock sample, since as the contact area increases, the fracture becomes stiffer. Correspondingly, the detailed characteristics of the contact area of fractures are expected to play a major role in WIFF-related attenuation. To study this topic, we consider a simple model consisting of a horizontal fracture located at the center of a porous rock sample and represented by a number of rectangular cracks of constant height separated by contact areas. The cracks are modelled as highly compliant, porous, and permeable heterogeneities, which are hydraulically connected to the background material. We include a number of rectangular regions of background material separating the cracks, which represent the presence of contact areas of the fracture. In order to estimate the WIFF effects, we apply numerical oscillatory relaxation tests based on the quasi-static poro-elastic equations. The equivalent undrained, complex plane-wave modulus, which allows to estimate seismic attenuation and velocity dispersion for the vertical direction of propagation, is expressed in terms of the imposed displacement and the resulting average vertical stress at the top boundary. In order to explore the effects of the presence of fracture contact areas on WIFF effects, we perform an exhaustive sensitivity analysis considering different

  12. Pfaffosidic Fraction from Hebanthe paniculata Induces Cell Cycle Arrest and Caspase-3-Induced Apoptosis in HepG2 Cells

    Directory of Open Access Journals (Sweden)

    Tereza Cristina da Silva

    2015-01-01

    Full Text Available Hebanthe paniculata roots (formerly Pfaffia paniculata and popularly known as Brazilian ginseng show antineoplastic, chemopreventive, and antiproliferative properties. Functional properties of these roots and their extracts are usually attributed to the pfaffosidic fraction, which is composed mainly by pfaffosides A–F. However, the therapeutic potential of this fraction in cancer cells is not yet entirely understood. This study aimed to analyze the antitumoral effects of the purified pfaffosidic fraction or saponinic fraction on the human hepatocellular carcinoma HepG2 cell line. Cellular viability, proliferation, and apoptosis were evaluated, respectively, by MTT assay, BrdU incorporation, activated caspase-3 immunocytochemistry, and DNA fragmentation assay. Cell cycle was analyzed by flow cytometry and the cell cycle-related proteins were analyzed by quantitative PCR and Western blot. The cells exposed to pfaffosidic fraction had reduced viability and cellular growth, induced G2/M at 48 h or S at 72 h arrest, and increased sub-G1 cell population via cyclin E downregulation, p27KIP1 overexpression, and caspase-3-induced apoptosis, without affecting the DNA integrity. Antitumoral effects of pfaffosidic fraction from H. paniculata in HepG2 cells originated by multimechanisms of action might be associated with cell cycle arrest in the S phase, by CDK2 and cyclin E downregulation and p27KIP1 overexpression, besides induction of apoptosis through caspase-3 activation.

  13. Induced Accelerated Aging in Induced Pluripotent Stem Cell Lines from Patients with Parkinson’s Disease

    Science.gov (United States)

    2014-07-01

    8 Appendix 1: Generation of stable hNSC cell lines expressing inducible GFP- Progerin by retroviral ...Experimental protocol: Prepare stock solution: Polybrene (Millipore, Cat. No. TR-1003-G) 10 mg/ml, Doxycycline (Clontech, REF 631311)10 mg/ml, Retroviral ...next day when the cell confluency is 80-90%, we start retroviral infection 3. Chang NSC medium containing 4 ug/ml polybrene in each well of 12 well

  14. Neuroprotection by GH against excitotoxic-induced cell death in retinal ganglion cells.

    Science.gov (United States)

    Martínez-Moreno, Carlos G; Ávila-Mendoza, José; Wu, Yilun; Arellanes-Licea, Elvira Del Carmen; Louie, Marcela; Luna, Maricela; Arámburo, Carlos; Harvey, Steve

    2016-08-01

    Retinal growth hormone (GH) has been shown to promote cell survival in retinal ganglion cells (RGCs) during developmental waves of apoptosis during chicken embryonic development. The possibility that it might also against excitotoxicity-induced cell death was therefore examined in the present study, which utilized quail-derived QNR/D cells as an in vitro RGC model. QNR/D cell death was induced by glutamate in the presence of BSO (buthionine sulfoxamide) (an enhancer of oxidative stress), but this was significantly reduced (PGH (rcGH). Similarly, QNR/D cells that had been prior transfected with a GH plasmid to overexpress secreted and non-secreted GH. This treatment reduced the number of TUNEL-labeled cells and blocked their release of lactate dehydrogenase (LDH). In a further experiment with dissected neuroretinal explants from ED (embryonic day) 10 embryos, rcGH treatment of the explants also reduced (PGH-overexpressing QNR/D cells. As rcGH treatment and GH-overexpression cells also increased the content of IGF-1 and IGF-1 mRNA this neuroprotective action of GH is likely to be mediated, at least partially, through an IGF-1 mechanism. This possibility is supported by the fact that the siRNA knockdown of GH or IGF-1 significantly reduced QNR/D cell viability, as did the immunoneutralization of IGF-1. GH is therefore neuroprotective against excitotoxicity-induced RGC cell death by anti-apoptotic actions involving IGF-1 stimulation.

  15. Efficient generation of rat induced pluripotent stem cells using a non-viral inducible vector.

    Directory of Open Access Journals (Sweden)

    Claudia Merkl

    Full Text Available Current methods of generating rat induced pluripotent stem cells are based on viral transduction of pluripotency inducing genes (Oct4, Sox2, c-myc and Klf4 into somatic cells. These activate endogenous pluripotency genes and reprogram the identity of the cell to an undifferentiated state. Epigenetic silencing of exogenous genes has to occur to allow normal iPS cell differentiation. To gain more control over the expression of exogenous reprogramming factors, we used a novel doxycycline-inducible plasmid vector encoding Oct4, Sox2, c-Myc and Klf4. To ensure efficient and controlled generation of iPS cells by plasmid transfection we equipped the reprogramming vector with a bacteriophage φC31 attB site and used a φC31 integrase expression vector to enhance vector integration. A series of doxycycline-independent rat iPS cell lines were established. These were characterized by immunocytochemical detection of Oct4, SSEA1 and SSEA4, alkaline phosphatase staining, methylation analysis of the endogenous Oct4 promoter and RT-PCR analysis of endogenous rat pluripotency genes. We also determined the number of vector integrations and the extent to which reprogramming factor gene expression was controlled. Protocols were developed to generate embryoid bodies and rat iPS cells demonstrated as pluripotent by generating derivatives of all three embryonic germ layers in vitro, and teratoma formation in vivo. All data suggest that our rat iPS cells, generated by plasmid based reprogramming, are similar to rat ES cells. Methods of DNA transfection, protein transduction and feeder-free monolayer culture of rat iPS cells were established to enable future applications.

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

    Science.gov (United States)

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

    2016-03-01

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

  17. Cell entry of Lassa virus induces tyrosine phosphorylation of dystroglycan.

    Science.gov (United States)

    Moraz, Marie-Laurence; Pythoud, Christelle; Turk, Rolf; Rothenberger, Sylvia; Pasquato, Antonella; Campbell, Kevin P; Kunz, Stefan

    2013-05-01

    The extracellular matrix (ECM) receptor dystroglycan (DG) serves as a cellular receptor for the highly pathogenic arenavirus Lassa virus (LASV) that causes a haemorrhagic fever with high mortality in human. In the host cell, DG provides a molecular link between the ECM and the actin cytoskeleton via the adapter proteins utrophin or dystrophin. Here we investigated post-translational modifications of DG in the context of LASV cell entry. Using the tyrosine kinase inhibitor genistein, we found that tyrosine kinases are required for efficient internalization of virus particles, but not virus-receptor binding. Engagement of cellular DG by LASV envelope glycoprotein (LASV GP) in human epithelial cells induced tyrosine phosphorylation of the cytoplasmic domain of DG. LASV GP binding to DG further resulted in dissociation of the adapter protein utrophin from virus-bound DG. This virus-induced dissociation of utrophin was affected by genistein treatment, suggesting a role of receptor tyrosine phosphorylation in the process.

  18. Targeted cancer cell death induced by biofunctionalized magnetic nanowires

    KAUST Repository

    Contreras, Maria F.

    2014-02-01

    Magnetic micro and nanomaterials are increasingly interesting for biomedical applications since they possess many advantageous properties: they can become biocompatible, they can be functionalized to target specific cells and they can be remotely manipulated by magnetic fields. The goal of this study is to use antibody-functionalized nickel nanowires (Ab-NWs) as an alternative method in cancer therapy overcoming the limitations of current treatments that lack specificity and are highly cytotoxic. Ab-NWs have been incubated with cancer cells and a 12% drop on cell viability was observed for a treatment of only 10 minutes and an alternating magnetic field of low intensity and low frequency. It is believed that the Ab-NWs vibrate transmitting a mechanical force to the targeted cells inducing cell death. © 2014 IEEE.

  19. Advances in the study on induced pluripotent stem cells

    Institute of Scientific and Technical Information of China (English)

    LIU Shuang; DUAN EnKui

    2008-01-01

    Recently, the study on "induced pluripotent stem cells" (iPS cells) has made a great breakthrough, and it is considered as a new milestone in the history of life science. This progress has updated our traditional concepts about pluripotency control, and provided people with a brand-new strategy for somatic cell nuclear reprogramming. In virtue of its availability and stability, this method holds great potential in both biological and clinical research. In order to introduce this rising field of study, this paper starts with an overview of the development of iPS cell establishment, describes the key steps in generating iPS cells, elaborates several relevant scientific issues, and evaluates its current restrictions and promises in future research.

  20. Generation of induced pluripotent stem cells from human cord blood.

    Science.gov (United States)

    Haase, Alexandra; Olmer, Ruth; Schwanke, Kristin; Wunderlich, Stephanie; Merkert, Sylvia; Hess, Christian; Zweigerdt, Robert; Gruh, Ina; Meyer, Johann; Wagner, Stefan; Maier, Lars S; Han, Dong Wook; Glage, Silke; Miller, Konstantin; Fischer, Philipp; Schöler, Hans R; Martin, Ulrich

    2009-10-02

    Induced pluripotent stem cells (iPSCs) may represent an ideal cell source for future regenerative therapies. A critical issue concerning the clinical use of patient-specific iPSCs is the accumulation of mutations in somatic (stem) cells over an organism's lifetime. Acquired somatic mutations are passed onto iPSCs during reprogramming and may be associated with loss of cellular functions and cancer formation. Here we report the generation of human iPSCs from cord blood (CB) as a juvenescent cell source. CBiPSCs show characteristics typical of embryonic stem cells and can be differentiated into derivatives of all three germ layers, including functional cardiomyocytes. For future therapeutic production of autologous and allogeneic iPSC derivatives, CB could be routinely harvested for public and commercial CB banks without any donor risk. CB could readily become available for pediatric patients and, in particular, for newborns with genetic diseases or congenital malformations.

  1. Trichodermin induces cell apoptosis through mitochondrial dysfunction and endoplasmic reticulum stress in human chondrosarcoma cells

    Energy Technology Data Exchange (ETDEWEB)

    Su, Chen-Ming [Graduate Institute of Basic Medical Science, China Medical University, Taichung, Taiwan (China); Wang, Shih-Wei [Department of Medicine, Mackay Medical College, New Taipei City, Taiwan (China); Lee, Tzong-Huei [Graduate Institute of Pharmacognosy, Taipei Medical University, Taipei, Taiwan (China); Tzeng, Wen-Pei [Graduate Institute of Sports and Health, National Changhua University of Education, Changhua, Taiwan (China); Hsiao, Che-Jen [School of Respiratory Therapy, College of Medicine, Taipei Medical University, Taipei, Taiwan (China); Liu, Shih-Chia [Department of Orthopaedics, Mackay Memorial Hospital, Taipei, Taiwan (China); Tang, Chih-Hsin, E-mail: chtang@mail.cmu.edu.tw [Graduate Institute of Basic Medical Science, China Medical University, Taichung, Taiwan (China); Department of Pharmacology, School of Medicine, China Medical University, Taichung, Taiwan (China); Department of Biotechnology, College of Health Science, Asia University, Taichung, Taiwan (China)

    2013-10-15

    Chondrosarcoma is the second most common primary bone tumor, and it responds poorly to both chemotherapy and radiation treatment. Nalanthamala psidii was described originally as Myxosporium in 1926. This is the first study to investigate the anti-tumor activity of trichodermin (trichothec-9-en-4-ol, 12,13-epoxy-, acetate), an endophytic fungal metabolite from N. psidii against human chondrosarcoma cells. We demonstrated that trichodermin induced cell apoptosis in human chondrosarcoma cell lines (JJ012 and SW1353 cells) instead of primary chondrocytes. In addition, trichodermin triggered endoplasmic reticulum (ER) stress protein levels of IRE1, p-PERK, GRP78, and GRP94, which were characterized by changes in cytosolic calcium levels. Furthermore, trichodermin induced the upregulation of Bax and Bid, the downregulation of Bcl-2, and the dysfunction of mitochondria, which released cytochrome c and activated caspase-3 in human chondrosarcoma. In addition, animal experiments illustrated reduced tumor volume, which led to an increased number of terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL)-positive cells and an increased level of cleaved PARP protein following trichodermin treatment. Together, this study demonstrates that trichodermin is a novel anti-tumor agent against human chondrosarcoma cells both in vitro and in vivo via mitochondrial dysfunction and ER stress. - Highlights: • Trichodermin induces chondrosarcoma apoptosis. • ER stress is involved in trichodermin-induced cell death. • Trichodermin induces chondrosarcoma death in vivo.

  2. Cyclosporin A inhibits programmed cell death and cytochrome c release induced by fusicoccin in sycamore cells.

    Science.gov (United States)

    Contran, N; Cerana, R; Crosti, P; Malerba, M

    2007-01-01

    Programmed cell death plays a vital role in normal plant development, response to environmental stresses, and defense against pathogen attack. Different types of programmed cell death occur in plants and the involvement of mitochondria is still under investigation. In sycamore (Acer pseudoplatanus L.) cultured cells, the phytotoxin fusicoccin induces cell death that shows apoptotic features, including chromatin condensation, DNA fragmentation, and release of cytochrome c from mitochondria. In this work, we show that cyclosporin A, an inhibitor of the permeability transition pore of animal mitochondria, inhibits the cell death, DNA fragmentation, and cytochrome c release induced by fusicoccin. In addition, we show that fusicoccin induces a change in the shape of mitochondria which is not prevented by cyclosporin A. These results suggest that the release of cytochrome c induced by fusicoccin occurs through a cyclosporin A-sensitive system that is similar to the permeability transition pore of animal mitochondria and they make it tempting to speculate that this release may be involved in the phytotoxin-induced programmed cell death of sycamore cells.

  3. Prostaglandin E2 potentiates mesenchymal stem cell-induced IL-10+IFN-γ+CD4+ regulatory T cells to control transplant arteriosclerosis.

    Science.gov (United States)

    Hsu, Wan-Tseng; Lin, Cheng-Hsin; Chiang, Bor-Luen; Jui, Hsiang-Yiang; Wu, Kenneth Kun-Yu; Lee, Chii-Ming

    2013-03-01

    Mesenchymal stem cells (MSCs) are known for their immunomodulatory functions. We previously demonstrated that bone marrow-derived MSCs effectively control transplant arteriosclerosis (TA) by enhancing IL-10(+) and IFN-γ(+) cells. The objective of this study is to elucidate the mechanism by which MSCs induce IL-10(+)IFN-γ(+)CD4(+) regulatory T type 1 (T(R)1)-like cells. In an MLR system using porcine PBMCs, MSC-induced IL-10(+)IFN-γ(+)CD4(+) cells, which confer resistance to allogeneic proliferation in an IL-10-dependent manner, resemble T(R)1-like cells. Both cyclooxygenase-derived PGE(2) and IDO help to induce T(R)1-like cells by MSCs. MSCs constitutively secrete PGE(2), which is augmented in allogeneic reactions. However, T(R)1-like cells were deficient in PGE(2) and 4-fold less potent than were MSCs in suppressing MLR. PGE(2) mimetic supplements can enhance the immunosuppressive potency of T(R)1-like cells. In a porcine model of allogeneic femoral arterial transplantation, MSC-induced T(R)1-like cells combined with PGE(2), but not either alone, significantly reduced TA at the end of 6 wk (percentage of luminal area stenosis: T(R)1-like cells + PGE(2): 11 ± 10%; PGE(2) alone: 93 ± 8.7%; T(R)1-like cells alone: 88 ± 2.4% versus untreated 94 ± 0.9%, p < 0.001). These findings indicate that PGE(2) helps MSC-induced IL-10(+)IFN-γ(+)CD4(+) T(R)1-like cells inhibit TA. PGE(2) combined with MSC-induced T(R)1-like cells represents a new approach for achieving immune tolerance.

  4. Autophagy inhibitor chloroquine enhanced the cell death inducing effect of the flavonoid luteolin in metastatic squamous cell carcinoma cells.

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    Lien Verschooten

    Full Text Available BACKGROUND: Flavonoids are widely proposed as very interesting compounds with possible chemopreventive and therapeutic capacities. METHODS & RESULTS: In this study, we showed that in vitro treatment with the flavonoid Luteolin induced caspase-dependent cell death in a model of human cutaneous squamous cell carcinoma (SCC derived cells, representing a matched pair of primary tumor and its metastasis. Notably, no cytotoxic effects were observed in normal human keratinocytes when treated with similar doses of Luteolin. Luteolin-induced apoptosis was accompanied by inhibition of AKT signaling, and sensitivity decreased with tumor progression, as the primary MET1 SCC cells were considerably more sensitive to Luteolin than the isogenic metastatic MET4 cells. Extensive intracellular vacuolization was observed in Luteolin-treated MET4 cells, which were characterized as acidic lysosomal vacuoles, suggesting the involvement of autophagy. Transmission electron microscopy, mRFP-GFP-LC3 assay and p62 protein degradation, confirmed that Luteolin stimulated the autophagic process in the metastatic MET4 cells. Blocking autophagy using chloroquine magnified Luteolin-induced apoptosis in the metastatic SCC cells. CONCLUSION: Together, these results suggest that Luteolin has the capacity to induce selectively apoptotic cell death both in primary cutaneous SCC cells and in metastatic SCC cells in combination with chloroquine, an inhibitor of autophagosomal degradation. Hence, Luteolin might be a promising agent for the treatment of cutaneous SCC.

  5. TRICHOSTATIN A INHIBITS PROLIFERATION, INDUCES APOPTOSIS AND CELL CYCLE ARREST IN HELA CELLS

    Institute of Scientific and Technical Information of China (English)

    XU Zhou-min; WANG Yi-qun; MEI Qi; CHEN Jian; DU Jia; WEI Yan; XU Ying-chun

    2006-01-01

    Objective: The histone deacetylase inhibitors (HDACIS) have been shown to inhibit cancer cell proliferation, stimulate apoptosis, an induce cell cycle arrest. Our purpose was to investigate the antiproliferative effects of a HDACI, trichostatin A (TSA), against human cervical cancer cells (HeLa). Methods: HeLa cells were treated in vitro with various concentrations of TSA. The inhibitory effect of TSA on the growth of HeLa cells was measured by MTT assay. To detect the characteristic of apoptosis chromatin condensation, HeLa cells were stained with Hoechst 33258 in the presence of TSA. Induction of cell cycle arrest was studied by flow cytometry. Changes in gene expression of p53, p21Waf1 and p27Kip1 were studied by semiquantitative RT-PCR. Results: TSA inhibited cell growth in a time- and dose-dependent manner. Hoechst 33258 staining assay showed that TSA induced apoptosis. Cell cycle analysis indicated that treatment with TSA decreased the proportion of cells in S phase and increased the proportion of cells in G0/G1 and/or G2/M phases of the cell cycle. This was concomitant with overexpression of genes related to malignant phenotype, including an increase in p53, p21Waf1 and p27Kip1. Conclusion: These results suggest that TSA is effective in inhibiting growth of HeLa cells in vitro. The findings raise the possibility that TSA may prove particularly effective in treatment of cervical cancers.

  6. Lipopolysaccharide-induced multinuclear cells: Increased internalization of polystyrene beads and possible signals for cell fusion

    Energy Technology Data Exchange (ETDEWEB)

    Nakanishi-Matsui, Mayumi, E-mail: nakanim@iwate-med.ac.jp; Yano, Shio; Futai, Masamitsu

    2013-11-01

    Highlights: •LPS induces multinuclear cells from murine macrophage-derived RAW264.7 cells. •Large beads are internalized by cells actively fusing to become multinuclear. •The multinuclear cell formation is inhibited by anti-inflammatory cytokine, IL10. •Signal transduction for cell fusion is different from that for inflammation. -- Abstract: A murine macrophage-derived line, RAW264.7, becomes multinuclear on stimulation with lipopolysaccharide (LPS), an outer membrane component of Gram-negative bacteria. These multinuclear cells internalized more polystyrene beads than mononuclear cells or osteoclasts (Nakanishi-Matsui, M., Yano, S., Matsumoto, N., and Futai, M., 2012). In this study, we analyzed the time courses of cell fusion in the presence of large beads. They were internalized into cells actively fusing to become multinuclear. However, the multinuclear cells once formed showed only low phagocytosis activity. These results suggest that formation of the multinuclear cells and bead internalization took place simultaneously. The formation of multinuclear cells was blocked by inhibitors for phosphoinositide 3-kinase, phospholipase C, calcineurin, and c-Jun N-terminal kinase. In addition, interleukin 6 and 10 also exhibited inhibitory effects. These signaling molecules and cytokines may play a crucial role in the LPS-induced multinuclear cell formation.

  7. Involvement of p53 in cell death following cell cycle arrest and mitotic catastrophe induced by rotenone

    OpenAIRE

    Gonçalves, António Pedro; Máximo, Valdemar; Lima, Jorge; Keshav K Singh; Soares, Paula; Videira, Arnaldo

    2011-01-01

    In order to investigate the cell death-inducing effects of rotenone, a plant extract commonly used as a mitochondrial complex I inhibitor, we studied cancer cell lines with different genetic backgrounds. Rotenone inhibits cell growth through the induction of cell death and cell cycle arrest, associated with the development of mitotic catastrophe. The cell death inducer staurosporine potentiates the inhibition of cell growth by rotenone in a dose-dependent synergistic manner. The tumor suppres...

  8. Human bone marrow mesenchymal stem cells induce collagen production and tongue cancer invasion.

    Directory of Open Access Journals (Sweden)

    Sirpa Salo

    Full Text Available Tumor microenvironment (TME is an active player in carcinogenesis and changes in its composition modify cancer growth. Carcinoma-associated fibroblasts, bone marrow-derived multipotent mesenchymal stem cells (BMMSCs, and inflammatory cells can all affect the composition of TME leading to changes in proliferation, invasion and metastasis formation of carcinoma cells. In this study, we confirmed an interaction between BMMSCs and oral tongue squamous cell carcinoma (OTSCC cells by analyzing the invasion progression and gene expression pattern. In a 3-dimensional myoma organotypic invasion model the presence of BMMSCs inhibited the proliferation but increased the invasion of OTSCC cells. Furthermore, the signals originating from OTSCC cells up-regulated the expression of inflammatory chemokines by BMMSCs, whereas BMMSC products induced the expression of known invasion linked molecules by carcinoma cells. Particularly, after the cell-cell interactions, the chemokine CCL5 was abundantly secreted from BMMSCs and a function blocking antibody against CCL5 inhibited BMMSC enhanced cancer invasion area. However, CCL5 blocking antibody did not inhibit the depth of invasion. Additionally, after exposure to BMMSCs, the expression of type I collagen mRNA in OTSCC cells was markedly up-regulated. Interestingly, also high expression of type I collagen N-terminal propeptide (PINP in vivo correlated with the cancer-specific mortality of OTSCC patients, whereas there was no association between cancer tissue CCL5 levels and the clinical parameters. In conclusion, our results suggest that the interaction between BMMSC and carcinoma cells induce cytokine and matrix molecule expression, of which high level of type I collagen production correlates with the prognosis of OTSCC patients.

  9. Single-walled carbon nanotubes induce cytotoxicity and DNA damage via reactive oxygen species in human hepatocarcinoma cells.

    Science.gov (United States)

    Alarifi, Saud; Ali, Daoud; Verma, Ankit; Almajhdi, Fahad N; Al-Qahtani, Ahmed A

    2014-09-01

    Carbon nanotubes (CNTs) are gradually used in various areas including drug delivery, nanomedicine, biosensors, and electronics. The current study aimed to explore the DNA damage and cytotoxicity due to single-walled carbon nanotubes (SWCNTs) on human hepatocarcinoma cells (HepG2). Cellular proliferative assay showed the SWCNTs to exhibit a significant cell death in a dose- and time-dependent manner. However, SWCNTs induced significant intracellular reactive oxygen species (ROS) production and elevated lipid peroxidation, catalase, and superoxide dismutase in the HepG2 cells. SWCNTs also induced significant decrease in GSH and increase caspase-3 activity in HepG2 cells. DNA fragmentation analysis using the alkaline single-cell gel electrophoresis showed that the SWCNTs cause genotoxicity in a dose- and time-dependent manner. Therefore, the study points towards the capability of the SWCNTs to induce oxidative stress resulting cytotoxicity and genomic instability. This study warrants more careful assessment of SWCNTs before their industrial applications.

  10. Embryonic and induced pluripotent stem cells: understanding, creating, and exploiting the nano-niche for regenerative medicine.

    Science.gov (United States)

    Kingham, Emmajayne; Oreffo, Richard O C

    2013-03-26

    Embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs) have the capacity to differentiate into any specialized cell type of the human body, and therefore, ESC/iPSC-derived cell types offer great potential for regenerative medicine. However, key to realizing this potential requires a strong understanding of stem cell biology, techniques to maintain stem cells, and strategies to manipulate cells to efficiently direct cell differentiation toward a desired cell type. As nanoscale science and engineering continues to produce novel nanotechnology platforms, which inform, infiltrate, and impinge on many aspects of everyday life, it is no surprise that stem cell research is turning toward developments in nanotechnology to answer research questions and to overcome obstacles in regenerative medicine. Here we discuss recent advances in ESC and iPSC manipulation using nanomaterials and highlight future challenges within this area of research.

  11. Derivation, characterization and retinal differentiation of induced pluripotent stem cells

    Indian Academy of Sciences (India)

    Subba Rao Mekala; Vasundhara Vauhini; Usha Nagarajan; Savitri Maddileti; Subhash Gaddipati; Indumathi Mariappan

    2013-03-01

    Millions of people world over suffer visual disability due to retinal dystrophies which can be age-related or a genetic disorder resulting in gradual degeneration of the retinal pigmented epithelial (RPE) cells and photoreceptors. Therefore, cell replacement therapy offers a great promise in treating such diseases. Since the adult retina does not harbour any stem cells, alternative stem cell sources like the embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs) offer a great promise for generating different cell types of the retina. Here, we report the derivation of four iPSC lines from mouse embryonic fibroblasts (MEFs) using a cocktail of recombinant retroviruses carrying the genes for Oct4, Sox2, Klf4 and cMyc. The iPS clone MEF-4F3 was further characterized for stemness marker expression and stable reprogramming by immunocytochemistry, FACS and RT-PCR analysis. Methylation analysis of the nanog promoter confirmed the reprogrammed epigenetic state. Pluripotency was confirmed by embryoid body (EB) formation and lineage-specific marker expression. Also, upon retinal differentiation, patches of pigmented cells with typical cobble-stone phenotype similar to RPE cells are generated within 6 weeks and they expressed ZO-1 (tight junction protein), RPE65 and bestrophin (mature RPE markers) and showed phagocytic activity by the uptake of fluorescent latex beads.

  12. ETOPOSIDE INDUCES CHROMOSOMAL ABNORMALITIES IN SPERMATOCYTES AND SPERMATOGONIAL STEM CELLS

    Energy Technology Data Exchange (ETDEWEB)

    Marchetti, F; Pearson, F S; Bishop, J B; Wyrobek, A J

    2005-07-15

    Etoposide (ET) is a chemotherapeutic agent widely used in the treatment of leukemia, lymphomas and many solid tumors, such as testicular and ovarian cancers, that affect patients in their reproductive years. The purpose of the study was to use sperm FISH analyses to characterize the long-term effects of ET on male germ cells. We used a mouse model to characterize the induction of chromosomal aberrations (partial duplications and deletions) and whole chromosomal aneuploidies in sperm of mice treated with a clinical dose of ET. Semen samples were collected at 25 and 49 days after dosing to investigate the effects of ET on meiotic pachytene cells and spermatogonial stem-cells, respectively. ET treatment resulted in major increases in the frequencies of sperm carrying chromosomal aberrations in both meiotic pachytene (27- to 578-fold) and spermatogonial stem-cells (8- to 16-fold), but aneuploid sperm were induced only after treatment of meiotic cells (27-fold) with no persistent effects in stem cells. These results demonstrate that male meiotic germ cells are considerably more sensitive to ET than spermatogonial stem-cell and that increased frequencies of sperm with structural aberrations persist after spermatogonial stem-cell treatment. These findings predict that patients who undergo chemotherapy with ET may have transient elevations in the frequencies of aneuploid sperm, but more importantly, may have persistent elevations in the frequencies of sperm with chromosomal aberrations, placing them at higher risk for abnormal reproductive outcomes long after the end of their chemotherapy.

  13. Induced pluripotent stem cells and neurological disease models.

    Science.gov (United States)

    Cai, Sa; Chan, Ying-Shing; Shum, Daisy Kwok-Yan

    2014-02-25

    The availability of human stem cells heralds a new era for in vitro cell-based modeling of neurodevelopmental and neurodegenerative diseases. Adding to the excitement is the discovery that somatic cells of patients can be reprogrammed to a pluripotent state from which neural lineage cells that carry the disease genotype can be derived. These in vitro cell-based models of neurological diseases hold promise for monitoring of disease initiation and progression, and for testing of new drug treatments on the patient-derived cells. In this review, we focus on the prospective applications of different stem cell types for disease modeling and drug screening. We also highlight how the availability of patient-specific induced pluripotent stem cells (iPS cells) offers a unique opportunity for studying and modeling human neurodevelopmental and neurodegenerative diseases in vitro and for testing small molecules or other potential therapies for these disorders. Finally, the limitations of this technology from the standpoint of reprogramming efficiency and therapeutic safety are discussed.

  14. Modelling familial dysautonomia in human induced pluripotent stem cells.

    Science.gov (United States)

    Lee, Gabsang; Studer, Lorenz

    2011-08-12

    Induced pluripotent stem (iPS) cells have considerable promise as a novel tool for modelling human disease and for drug discovery. While the generation of disease-specific iPS cells has become routine, realizing the potential of iPS cells in disease modelling poses challenges at multiple fronts. Such challenges include selecting a suitable disease target, directing the fate of iPS cells into symptom-relevant cell populations, identifying disease-related phenotypes and showing reversibility of such phenotypes using genetic or pharmacological approaches. Finally, the system needs to be scalable for use in modern drug discovery. Here, we will discuss these points in the context of modelling familial dysautonomia (FD, Riley-Day syndrome, hereditary sensory and autonomic neuropathy III (HSAN-III)), a rare genetic disorder in the peripheral nervous system. We have demonstrated three disease-specific phenotypes in FD-iPS-derived cells that can be partially rescued by treating cells with the plant hormone kinetin. Here, we will discuss how to use FD-iPS cells further in high throughput drug discovery assays, in modelling disease severity and in performing mechanistic studies aimed at understanding disease pathogenesis. FD is a rare disease but represents an important testing ground for exploring the potential of iPS cell technology in modelling and treating human disease.

  15. Curcumin-induced Histone Acetylation in Malignant Hematologic Cells

    Institute of Scientific and Technical Information of China (English)

    Junbin HU; Yan WANG; Yan CHEN

    2009-01-01

    This study investigated the inhibitory effects of curcumin on proliferation of hemato-logical malignant cells in vitro and the anti-tumor mechanism at histone acetylation/histone deacety-lation levels.The effects of curcumin and histone deacetylase inhibitor trichostatin A (TSA) on the growth of Raji cells were tested by MTT assay.The expression of acetylated histone-3 (H3) in Raji,HL60 and K562 cells,and peripheral blood mononuclear cells (PBMCs) treated with curcumin or TSA was detected by immunohistochemistry and FACS.The results showed curcumin inhibited pro-liferation of Raji cells significantly in a time- and dose-dependent fashion,while exhibited low toxic-ity in PBMCs.Curcumin induced up-regulation of the expression of acetylated H3 dose-dependently in all malignant cell lines tested.In conclusion,curcumin inhibited proliferation of Raji cells selec-tively,enhanced the level of acetylated H3 in Raji,HL60,and K562 cells,which acted as a histone deacetylase inhibitor like TSA.Furthermore,up-regulation of H3 acetylation may play an important role in regulating the proliferation of Raji cells.

  16. Generation of Induced Pluripotent Stem Cells from Hair Follicle Bulge Neural Crest Stem Cells

    NARCIS (Netherlands)

    Ma, Ming-San; Czepiel, Marcin; Krause, Tina; Schaefer, Karl-Herbert; Boddeke, Erik; Copray, Sjef

    2014-01-01

    Induced pluripotent stem cells (iPSCs) are promising candidates for the study of disease models as well as for tissue engineering purposes. Part of a strategy to develop safe reprogramming technique is reducing the number of exogenous reprogramming factors. Some cells types are more prone to reprogr

  17. Protection of Bovine Mammary Epithelial Cells from Hydrogen Peroxide-Induced Oxidative Cell Damage by Resveratrol.

    Science.gov (United States)

    Jin, Xiaolu; Wang, Kai; Liu, Hongyun; Hu, Fuliang; Zhao, Fengqi; Liu, Jianxin

    2016-01-01

    The mammary epithelial cells (MECs) of high-producing dairy cows are likely to be subject to oxidative stress (OS) due to the intensive cell metabolism. The objectives of this study were to investigate the cytoprotective effects of resveratrol against hydrogen peroxide- (H2O2-) induced OS in cultured bovine MECs (MAC-T). Pretreatment of MAC-T cells with resveratrol could rescue the decrease in cell viability and resulted in lower intracellular reactive oxygen species (ROS) accumulation after H2O2 exposure. Resveratrol helped MAC-T cells to prevent H2O2-induced endoplasmic reticulum stress and mitochondria-related cell apoptosis. Moreover, resveratrol induced mRNA expression of multiple antioxidant defense genes in MAC-T cells under normal/oxidative conditions. Nuclear factor erythroid 2-related factor 2 (Nrf2) was required for the cytoprotective effects on MAC-T cells by resveratrol, as knockdown of Nrf2 significantly abolished resveratrol-induced cytoprotective effects against OS. In addition, by using selective inhibitors, we further confirmed that the induction of Nrf2 by resveratrol was mediated through the prolonged activation of PI3K/Akt and ERK/MAPK pathways but negatively regulated by p38/MAPK pathway. Overall, resveratrol has beneficial effects on bovine MECs redox balance and may be potentially used as a therapeutic medicine against oxidative insult in lactating animals.

  18. Human Adipose Derived Stem Cells Induced Cell Apoptosis and S Phase Arrest in Bladder Tumor

    Directory of Open Access Journals (Sweden)

    Xi Yu

    2015-01-01

    Full Text Available The aim of this study was to determine the effect of human adipose derived stem cells (ADSCs on the viability and apoptosis of human bladder cancer cells. EJ and T24 cells were cocultured with ADSCs or cultured with conditioned medium of ADSCs (ADSC-CM, respectively. The cell counting and colony formation assay showed ADSCs inhibited the proliferation of EJ and T24 cells. Cell viability assessment revealed that the secretions of ADSCs, in the form of conditioned medium, were able to decrease cancer cell viability. Wound-healing assay suggested ADSC-CM suppressed migration of T24 and EJ cells. Moreover, the results of the flow cytometry indicated that ADSC-CM was capable of inducing apoptosis of T24 cells and inducing S phase cell cycle arrest. Western blot revealed ADSC-CM increased the expression of cleaved caspase-3 and cleaved PARP, indicating that ADSC-CM induced apoptosis in a caspase-dependent way. PTEN/PI3K/Akt pathway and Bcl-2 family proteins were involved in the mechanism of this reaction. Our study indicated that ADSCs may provide a promising and practicable manner for bladder tumor therapy.

  19. Photodynamic therapy-induced programmed cell death in carcinoma cell lines

    Science.gov (United States)

    He, Xiao-Yan; Sikes, Robert A.; Thomsen, Sharon L.; Chung, L.; Jacques, Steven L.

    1993-06-01

    The mode of cell death following photodynamic therapy (PDT) was investigated from the perspective of programmed cell death (apoptosis). Human prostate carcinoma cells (PC3), human non-small cell lung carcinoma (H322a), and rat mammary carcinoma (MTF7) were treated by PDT following sensitization with dihematoporphyrin ether (DHE). The response of these carcinoma cell lines to PDT was variable. An examination of extracted cellular DNA by gel electrophoresis showed the characteristic DNA ladder pattern indicative of internucleosomal cleavage of DNA during apoptosis. MTF7 and PC3 responded to PDT by inducing apoptosis while H322a had no apoptotic response. The magnitude of the response and the PDT dosage required to induce the effect were different in PC3 and MTF7. MTF7 cells responded with rapid apoptosis at the dose of light and drug that yielded 50% cell death (LD50). In contrast, PC3 showed only marginal apoptosis at the LD50 but had a marked response at the LD85. Furthermore, the onset of apoptosis followed slower kinetics in PC3 (2 hr - 4 hr) than in MTF7 (cells were killed by PDT but failed to exhibit any apoptotic response. This study indicates that apoptosis may occur during PDT induced cell death, but this pathway is not universal for all cancer cell lines.

  20. Generation of functional podocytes from human induced pluripotent stem cells

    Directory of Open Access Journals (Sweden)

    Osele Ciampi

    2016-07-01

    Full Text Available Generating human podocytes in vitro could offer a unique opportunity to study human diseases. Here, we describe a simple and efficient protocol for obtaining functional podocytes in vitro from human induced pluripotent stem cells. Cells were exposed to a three-step protocol, which induced their differentiation into intermediate mesoderm, then into nephron progenitors and, finally, into mature podocytes. After differentiation, cells expressed the main podocyte markers, such as synaptopodin, WT1, α-Actinin-4, P-cadherin and nephrin at the protein and mRNA level, and showed the low proliferation rate typical of mature podocytes. Exposure to Angiotensin II significantly decreased the expression of podocyte genes and cells underwent cytoskeleton rearrangement. Cells were able to internalize albumin and self-assembled into chimeric 3D structures in combination with dissociated embryonic mouse kidney cells. Overall, these findings demonstrate the establishment of a robust protocol that, mimicking developmental stages, makes it possible to derive functional podocytes in vitro.

  1. Hypoxia-induced reactive oxygen species cause chromosomal abnormalities in endothelial cells in the tumor microenvironment.

    Directory of Open Access Journals (Sweden)

    Miyako Kondoh

    Full Text Available There is much evidence that hypoxia in the tumor microenvironment enhances tumor progression. In an earlier study, we reported abnormal phenotypes of tumor-associated endothelial cells such as those resistant to chemotherapy and chromosomal instability. Here we investigated the role of hypoxia in the acquisition of chromosomal abnormalities in endothelial cells. Tumor-associated endothelial cells isolated from human tumor xenografts showed chromosomal abnormalities, >30% of which were aneuploidy. Aneuploidy of the tumor-associated endothelial cells was also shown by simultaneous in-situ hybridization for chromosome 17 and by immunohistochemistry with anti-CD31 antibody for endothelial staining. The aneuploid cells were surrounded by a pimonidazole-positive area, indicating hypoxia. Human microvascular endothelial cells expressed hypoxia-inducible factor 1 and vascular endothelial growth factor A in response to either hypoxia or hypoxia-reoxygenation, and in these conditions, they acquired aneuploidy in 7 days. Induction of aneuploidy was inhibited by either inhibition of vascular endothelial growth factor signaling with vascular endothelial growth factor receptor 2 inhibitor or by inhibition of reactive oxygen species by N-acetyl-L-cysteine. These results indicate that hypoxia induces chromosomal abnormalities in endothelial cells through the induction of reactive oxygen species and excess signaling of vascular endothelial growth factor in the tumor microenvironment.

  2. Hypoxia-Induced Reactive Oxygen Species Cause Chromosomal Abnormalities in Endothelial Cells in the Tumor Microenvironment

    Science.gov (United States)

    Hida, Yasuhiro; Maishi, Nako; Towfik, Alam Mohammad; Inoue, Nobuo; Shindoh, Masanobu; Hida, Kyoko

    2013-01-01

    There is much evidence that hypoxia in the tumor microenvironment enhances tumor progression. In an earlier study, we reported abnormal phenotypes of tumor-associated endothelial cells such as those resistant to chemotherapy and chromosomal instability. Here we investigated the role of hypoxia in the acquisition of chromosomal abnormalities in endothelial cells. Tumor-associated endothelial cells isolated from human tumor xenografts showed chromosomal abnormalities, >30% of which were aneuploidy. Aneuploidy of the tumor-associated endothelial cells was also shown by simultaneous in-situ hybridization for chromosome 17 and by immunohistochemistry with anti-CD31 antibody for endothelial staining. The aneuploid cells were surrounded by a pimonidazole-positive area, indicating hypoxia. Human microvascular endothelial cells expressed hypoxia-inducible factor 1 and vascular endothelial growth factor A in response to either hypoxia or hypoxia-reoxygenation, and in these conditions, they acquired aneuploidy in 7 days. Induction of aneuploidy was inhibited by either inhibition of vascular endothelial growth factor signaling with vascular endothelial growth factor receptor 2 inhibitor or by inhibition of reactive oxygen species by N-acetyl-L-cysteine. These results indicate that hypoxia induces chromosomal abnormalities in endothelial cells through the induction of reactive oxygen species and excess signaling of vascular endothelial growth factor in the tumor microenvironment. PMID:24260373

  3. Deletion of the Mitochondrial Flavoprotein Apoptosis Inducing Factor (AIF) Induces β-Cell Apoptosis and Impairs β-Cell Mass

    Science.gov (United States)

    Schulthess, Fabienne T.; Katz, Sophie; Ardestani, Amin; Kawahira, Hiroshi; Georgia, Senta; Bosco, Domenico; Bhushan, Anil; Maedler, Kathrin

    2009-01-01

    Background Apoptosis is a hallmark of β-cell death in both type 1 and type 2 diabetes mellitus. Understanding how apoptosis contributes to β-cell turnover may lead to strategies to prevent progression of diabetes. A key mediator of apoptosis, mitochondrial function, and cell survival is apoptosis inducing factor (AIF). In the present study, we investigated the role of AIF on β-cell mass and survival using the Harlequin (Hq) mutant mice, which are hypomorphic for AIF. Methodology/Principal Findings Immunohistochemical evaluation of pancreata from Hq mutant mice displayed much smaller islets compared to wild-type mice (WT). Analysis of β-cell mass in these mice revealed a greater than 4-fold reduction in β-cell mass together with an 8-fold increase in β-cell apoptosis. Analysis of cell cycle dynamics, using BrdU pulse as a marker for cells in S-phase, did not detect significant differences in the frequency of β-cells in S-phase. In contrast, double staining for phosphorylated Histone H3 and insulin showed a 3-fold increase in β-cells in the G2 phase in Hq mutant mice, but no differences in M-phase compared to WT mice. This suggests that the β-cells from Hq mutant mice are arrested in the G2 phase and are unlikely to complete the cell cycle. β-cells from Hq mutant mice display increased sensitivity to hydrogen peroxide-induced apoptosis, which was confirmed in human islets in which AIF was depleted by siRNA. AIF deficiency had no effect on glucose stimulated insulin secretion, but the impaired effect of hydrogen peroxide on β-cell function was potentiated. Conclusions/Significance Our results indicate that AIF is essential for maintaining β-cell mass and for oxidative stress response. A decrease in the oxidative phosphorylation capacity may counteract the development of diabetes, despite its deleterious effects on β-cell survival. PMID:19197367

  4. Deletion of the mitochondrial flavoprotein apoptosis inducing factor (AIF induces beta-cell apoptosis and impairs beta-cell mass.

    Directory of Open Access Journals (Sweden)

    Fabienne T Schulthess

    Full Text Available BACKGROUND: Apoptosis is a hallmark of beta-cell death in both type 1 and type 2 diabetes mellitus. Understanding how apoptosis contributes to beta-cell turnover may lead to strategies to prevent progression of diabetes. A key mediator of apoptosis, mitochondrial function, and cell survival is apoptosis inducing factor (AIF. In the present study, we investigated the role of AIF on beta-cell mass and survival using the Harlequin (Hq mutant mice, which are hypomorphic for AIF. METHODOLOGY/PRINCIPAL FINDINGS: Immunohistochemical evaluation of pancreata from Hq mutant mice displayed much smaller islets compared to wild-type mice (WT. Analysis of beta-cell mass in these mice revealed a greater than 4-fold reduction in beta-cell mass together with an 8-fold increase in beta-cell apoptosis. Analysis of cell cycle dynamics, using BrdU pulse as a marker for cells in S-phase, did not detect significant differences in the frequency of beta-cells in S-phase. In contrast, double staining for phosphorylated Histone H3 and insulin showed a 3-fold increase in beta-cells in the G2 phase in Hq mutant mice, but no differences in M-phase compared to WT mice. This suggests that the beta-cells from Hq mutant mice are arrested in the G2 phase and are unlikely to complete the cell cycle. beta-cells from Hq mutant mice display increased sensitivity to hydrogen peroxide-induced apoptosis, which was confirmed in human islets in which AIF was depleted by siRNA. AIF deficiency had no effect on glucose stimulated insulin secretion, but the impaired effect of hydrogen peroxide on beta-cell function was potentiated. CONCLUSIONS/SIGNIFICANCE: Our results indicate that AIF is essential for maintaining beta-cell mass and for oxidative stress response. A decrease in the oxidative phosphorylation capacity may counteract the development of diabetes, despite its deleterious effects on beta-cell survival.

  5. Fibrogenic Lung Injury Induces Non-Cell-Autonomous Fibroblast Invasion.

    Science.gov (United States)

    Ahluwalia, Neil; Grasberger, Paula E; Mugo, Brian M; Feghali-Bostwick, Carol; Pardo, Annie; Selman, Moisés; Lagares, David; Tager, Andrew M

    2016-06-01

    Pathologic accumulation of fibroblasts in pulmonary fibrosis appears to depend on their invasion through basement membranes and extracellular matrices. Fibroblasts from the fibrotic lungs of patients with idiopathic pulmonary fibrosis (IPF) have been demonstrated to acquire a phenotype characterized by increased cell-autonomous invasion. Here, we investigated whether fibroblast invasion is further stimulated by soluble mediators induced by lung injury. We found that bronchoalveolar lavage fluids from bleomycin-challenged mice or patients with IPF contain mediators that dramatically increase the matrix invasion of primary lung fibroblasts. Further characterization of this non-cell-autonomous fibroblast invasion suggested that the mediators driving this process are produced locally after lung injury and are preferentially produced by fibrogenic (e.g., bleomycin-induced) rather than nonfibrogenic (e.g., LPS-induced) lung injury. Comparison of invasion and migration induced by a series of fibroblast-active mediators indicated that these two forms of fibroblast movement are directed by distinct sets of stimuli. Finally, knockdown of multiple different membrane receptors, including platelet-derived growth factor receptor-β, lysophosphatidic acid 1, epidermal growth factor receptor, and fibroblast growth factor receptor 2, mitigated the non-cell-autonomous fibroblast invasion induced by bronchoalveolar lavage from bleomycin-injured mice, suggesting that multiple different mediators drive fibroblast invasion in pulmonary fibrosis. The magnitude of this mediator-driven fibroblast invasion suggests that its inhibition could be a novel therapeutic strategy for pulmonary fibrosis. Further elaboration of the molecular mechanisms that drive non-cell-autonomous fibroblast invasion consequently may provide a rich set of novel drug targets for the treatment of IPF and other fibrotic lung diseases.

  6. Induced Pluripotent Stem Cell as a New Source for Cancer Immunotherapy.

    Science.gov (United States)

    Rami, Farzaneh; Mollainezhad, Halimeh; Salehi, Mansoor

    2016-01-01

    The immune system consists of cells, proteins, and other molecules that beside each other have a protective function for the host against foreign pathogens. One of the most essential features of the immune system is distinguishability between self- and non-self-cells. This function has an important role in limiting development and progression of cancer cells. In this case, the immune system can detect tumor cell as a foreign pathogen; so, it can be effective in elimination of tumors in their early phases of development. This ability of the immune system resulted in the development of a novel therapeutic field for cancer treatment using host immune components which is called cancer immunotherapy. The main purpose of cancer immunotherapy is stimulation of a strong immune response against the tumor cells that can result from expressing either the immune activator cytokines in the tumor area or gene-modified immune cells. Because of the problems of culturing and manipulating immune cells ex vivo, in recent years, embryonic stem cell (ESC) and induced pluripotent stem cell (iPSC) have been used as new sources for generation of modified immune stimulatory cells. In this paper, we reviewed some of the progressions in iPSC technology for cancer immunotherapy.

  7. Induced Pluripotent Stem Cell as a New Source for Cancer Immunotherapy

    Directory of Open Access Journals (Sweden)

    Farzaneh Rami

    2016-01-01

    Full Text Available The immune system consists of cells, proteins, and other molecules that beside each other have a protective function for the host against foreign pathogens. One of the most essential features of the immune system is distinguishability between self- and non-self-cells. This function has an important role in limiting development and progression of cancer cells. In this case, the immune system can detect tumor cell as a foreign pathogen; so, it can be effective in elimination of tumors in their early phases of development. This ability of the immune system resulted in the development of a novel therapeutic field for cancer treatment using host immune components which is called cancer immunotherapy. The main purpose of cancer immunotherapy is stimulation of a strong immune response against the tumor cells that can result from expressing either the immune activator cytokines in the tumor area or gene-modified immune cells. Because of the problems of culturing and manipulating immune cells ex vivo, in recent years, embryonic stem cell (ESC and induced pluripotent stem cell (iPSC have been used as new sources for generation of modified immune stimulatory cells. In this paper, we reviewed some of the progressions in iPSC technology for cancer immunotherapy.

  8. Limited Gene Expression Variation in Human Embryonic Stem Cell and Induced Pluripotent Stem Cell Derived Endothelial Cells

    OpenAIRE

    2013-01-01

    Recent evidence suggests human embryonic stem cell (hESC) and induced pluripotent stem (iPS) cell lines have differences in their epigenetic marks and transcriptomes, yet the impact of these differences on subsequent terminally differentiated cells is less well understood. Comparison of purified, homogeneous populations of somatic cells derived from multiple independent human iPS and ES lines will be required to address this critical question. Here, we report a differentiation protocol based ...

  9. Increased anion channel activity is an unavoidable event in ozone-induced programmed cell death.

    Directory of Open Access Journals (Sweden)

    Takashi Kadono

    Full Text Available BACKGROUND: Ozone is a major secondary air pollutant often reaching high concentrations in urban areas under strong daylight, high temperature and stagnant high-pressure systems. Ozone in the troposphere is a pollutant that is harmful to the plant. PRINCIPAL FINDINGS: By exposing cells to a strong pulse of ozonized air, an acute cell death was observed in suspension cells of Arabidopsis thaliana used as a model. We demonstrated that O(3 treatment induced the activation of a plasma membrane anion channel that is an early prerequisite of O(3-induced cell death in A. thaliana. Our data further suggest interplay of anion channel activation with well known plant responses to O(3, Ca(2+ influx and NADPH-oxidase generated reactive oxygen species (ROS in mediating the oxidative cell death. This interplay might be fuelled by several mechanisms in addition to the direct ROS generation by O(3; namely, H(2O(2 generation by salicylic and abscisic acids. Anion channel activation was also shown to promote the accumulation of transcripts encoding vacuolar processing enzymes, a family of proteases previously reported to contribute to the disruption of vacuole integrity observed during programmed cell death. SIGNIFICANCE: Collectively, our data indicate that anion efflux is an early key component of morphological and biochemical events leading to O(3-induced programmed cell death. Because ion channels and more specifically anion channels assume a crucial position in cells, an understanding about the underlying role(s for ion channels in the signalling pathway leading to programmed cell death is a subject that warrants future investigation.

  10. Oxidative stress induces mitochondrial fragmentation in frataxin-deficient cells

    Energy Technology Data Exchange (ETDEWEB)

    Lefevre, Sophie [Mitochondria, Metals and Oxidative Stress Laboratory, Institut Jacques Monod, CNRS-Universite Paris-Diderot, Sorbonne Paris Cite, 15 rue Helene Brion, 75205 Paris cedex 13 (France); ED515 UPMC, 4 place Jussieu 75005 Paris (France); Sliwa, Dominika [Mitochondria, Metals and Oxidative Stress Laboratory, Institut Jacques Monod, CNRS-Universite Paris-Diderot, Sorbonne Paris Cite, 15 rue Helene Brion, 75205 Paris cedex 13 (France); Rustin, Pierre [Inserm, U676, Physiopathology and Therapy of Mitochondrial Disease Laboratory, 75019 Paris (France); Universite Paris-Diderot, Faculte de Medecine Denis Diderot, IFR02 Paris (France); Camadro, Jean-Michel [Mitochondria, Metals and Oxidative Stress Laboratory, Institut Jacques Monod, CNRS-Universite Paris-Diderot, Sorbonne Paris Cite, 15 rue Helene Brion, 75205 Paris cedex 13 (France); Santos, Renata, E-mail: santos.renata@ijm.univ-paris-diderot.fr [Mitochondria, Metals and Oxidative Stress Laboratory, Institut Jacques Monod, CNRS-Universite Paris-Diderot, Sorbonne Paris Cite, 15 rue Helene Brion, 75205 Paris cedex 13 (France)

    2012-02-10

    Highlights: Black-Right-Pointing-Pointer Yeast frataxin-deficiency leads to increased proportion of fragmented mitochondria. Black-Right-Pointing-Pointer Oxidative stress induces complete mitochondrial fragmentation in {Delta}yfh1 cells. Black-Right-Pointing-Pointer Oxidative stress increases mitochondrial fragmentation in patient fibroblasts. Black-Right-Pointing-Pointer Inhibition of mitochondrial fission in {Delta}yfh1 induces oxidative stress resistance. -- Abstract: Friedreich ataxia (FA) is the most common recessive neurodegenerative disease. It is caused by deficiency in mitochondrial frataxin, which participates in iron-sulfur cluster assembly. Yeast cells lacking frataxin ({Delta}yfh1 mutant) showed an increased proportion of fragmented mitochondria compared to wild-type. In addition, oxidative stress induced complete fragmentation of mitochondria in {Delta}yfh1 cells. Genetically controlled inhibition of mitochondrial fission in these cells led to increased resistance to oxidative stress. Here we present evidence that in yeast frataxin-deficiency interferes with mitochondrial dynamics, which might therefore be relevant for the pathophysiology of FA.

  11. Platelet-Activating Factor Induces Th17 Cell Differentiation

    Directory of Open Access Journals (Sweden)

    Anne-Marie Drolet

    2011-01-01

    Full Text Available Th17 cells have been implicated in a number of inflammatory and autoimmune diseases. The phospholipid mediator platelet-activating factor (PAF is found in increased concentrations in inflammatory lesions and has been shown to induce IL-6 production. We investigated whether PAF could affect the development of Th17 cells. Picomolar concentrations of PAF induced IL-23, IL-6, and IL-1β expression in monocyte-derived Langerhans cells (LCs and in keratinocytes. Moreover, when LC were pretreated with PAF and then cocultured with anti-CD3- and anti-CD28-activated T cells, the latter developed a Th17 phenotype, with a significant increase in the expression of the transcriptional regulator RORγt and enhanced expression of IL-17, IL-21, and IL-22. PAF-induced Th17 development was prevented by the PAF receptor antagonist WEB2086 and by neutralizing antibodies to IL-23 and IL-6R. This may constitute a previously unknown stimulus for the development and persistence of inflammatory processes that could be amenable to pharmacologic intervention.

  12. Salidroside inhibits endogenous hydrogen peroxide induced cytotoxicity of endothelial cells.

    Science.gov (United States)

    Zhao, Xingyu; Jin, Lianhai; Shen, Nan; Xu, Bin; Zhang, Wei; Zhu, Hongli; Luo, Zhengli

    2013-01-01

    Salidroside, a phenylpropanoid glycoside isolated from Rhodiola rosea L., shows potent antioxidant property. Herein, we investigated the protective effects of salidroside against hydrogen peroxide (H2O2)-induced oxidative damage in human endothelial cells (EVC-304). EVC-304 cells were incubated in the presence or absence of low steady states of H2O2 (3-4 µM) generated by glucose oxidase (GOX) with or without salidroside. 3(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), superoxide dismutase (SOD), malondialdehyde (MDA), and glutathione (GSH) assays were performed, together with Hoechst 33258 staining and flow cytometric analysis using Annexin-V and propidium iodide (PI) label. The results indicated that salidroside pretreatment attenuated endogenous H2O2 induced apoptotic cell death in EVC-304 cells in a dose-dependent pattern. Furthermore, Western blot data revealed that salidroside inhibited activation of caspase-3, 9 and cleavage of poly(ADP-ribose) polymerase (PARP) induced by endogenous H2O2. It also decreased the expression of Bax and rescued the balance of pro- and anti-apoptotic proteins. All these results demonstrated that salidroside may present a potential therapy for oxidative stress in cardiovascular and cerebrovascular diseases.

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

    Institute of Scientific and Technical Information of China (English)

    Wenwen Zhong; Yang Liu; Hui Tian

    2009-01-01

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

  14. How Heme Oxygenase-1 Prevents Heme-Induced Cell Death.

    Directory of Open Access Journals (Sweden)

    Lilibeth Lanceta

    Full Text Available Earlier observations indicate that free heme is selectively toxic to cells lacking heme oxygenase-1 (HO-1 but how this enzyme prevents heme toxicity remains unexplained. Here, using A549 (human lung cancer and immortalized human bronchial epithelial cells incubated with exogenous heme, we find knock-down of HO-1 using siRNA does promote the accumulation of cell-associated heme and heme-induced cell death. However, it appears that the toxic effects of heme are exerted by "loose" (probably intralysosomal iron because cytotoxic effects of heme are lessened by pre-incubation of HO-1 deficient cells with desferrioxamine (which localizes preferentially in the lysosomal compartment. Desferrioxamine also decreases lysosomal rupture promoted by intracellularly generated hydrogen peroxide. Supporting the importance of endogenous oxidant production, both chemical and siRNA inhibition of catalase activity predisposes HO-1 deficient cells to heme-mediated killing. Importantly, it appears that HO-1 deficiency somehow blocks the induction of ferritin; control cells exposed to heme show ~10-fold increases in ferritin heavy chain expression whereas in heme-exposed HO-1 deficient cells ferritin expression is unchanged. Finally, overexpression of ferritin H chain in HO-1 deficient cells completely prevents heme-induced cytotoxicity. Although two other products of HO-1 activity--CO and bilirubin--have been invoked to explain HO-1-mediated cytoprotection, we conclude that, at least in this experimental system, HO-1 activity triggers the induction of ferritin and the latter is actually responsible for the cytoprotective effects of HO-1 activity.

  15. Numerical study of cell performance and local transport phenomena in PEM fuel cells with various flow channel area ratios

    Science.gov (United States)

    Wang, Xiao-Dong; Duan, Yuan-Yuan; Yan, Wei-Mon

    Three-dimensional models of proton exchange membrane fuel cells (PEMFCs) with parallel and interdigitated flow channel designs were developed including the effects of liquid water formation on the reactant gas transport. The models were used to investigate the effects of the flow channel area ratio and the cathode flow rate on the cell performance and local transport characteristics. The results reveal that at high operating voltages, the cell performance is independent of the flow channel designs and operating parameters, while at low operating voltages, both significantly affect cell performance. For the parallel flow channel design, as the flow channel area ratio increases the cell performance improves because fuel is transported into the diffusion layer and the catalyst layer mainly by diffusion. A larger flow channel area ratio increases the contact area between the fuel and the diffusion layer, which allows more fuel to directly diffuse into the porous layers to participate in the electrochemical reaction which enhances the reaction rates. For the interdigitated flow channel design, the baffle forces more fuel to enter the cell and participate in the electrochemical reaction, so the flow channel area ratio has less effect. Forced convection not only increases the fuel transport rates but also enhances the liquid water removal, thus interdigitated flow channel design has higher performance than the parallel flow channel design. The optimal performance for the interdigitated flow channel design occurs for a flow channel area ratio of 0.4. The cell performance also improves as the cathode flow rate increases. The effects of the flow channel area ratio and the cathode flow rate on cell performance are analyzed based on the local current densities, oxygen flow rates and liquid water concentrations inside the cell.

  16. Numerical study of cell performance and local transport phenomena in PEM fuel cells with various flow channel area ratios

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xiao-Dong [Department of Thermal Engineering, School of Mechanical Engineering, University of Science and Technology Beijing, Beijing 100083 (China); Duan, Yuan-Yuan [Key Laboratory of Thermal Science and Power Engineering of MOE, Tsinghua University, Beijing 100084 (China); Yan, Wei-Mon [Department of Mechatronic Engineering, Huafan University, Shih-Ting 22305 (China)

    2007-10-11

    Three-dimensional models of proton exchange membrane fuel cells (PEMFCs) with parallel and interdigitated flow channel designs were developed including the effects of liquid water formation on the reactant gas transport. The models were used to investigate the effects of the flow channel area ratio and the cathode flow rate on the cell performance and local transport characteristics. The results reveal that at high operating voltages, the cell performance is independent of the flow channel designs and operating parameters, while at low operating voltages, both significantly affect cell performance. For the parallel flow channel design, as the flow channel area ratio increases the cell performance improves because fuel is transported into the diffusion layer and the catalyst layer mainly by diffusion. A larger flow channel area ratio increases the contact area between the fuel and the diffusion layer, which allows more fuel to directly diffuse into the porous layers to participate in the electrochemical reaction which enhances the reaction rates. For the interdigitated flow channel design, the baffle forces more fuel to enter the cell and participate in the electrochemical reaction, so the flow channel area ratio has less effect. Forced convection not only increases the fuel transport rates but also enhances the liquid water removal, thus interdigitated flow channel design has higher performance than the parallel flow channel design. The optimal performance for the interdigitated flow channel design occurs for a flow channel area ratio of 0.4. The cell performance also improves as the cathode flow rate increases. The effects of the flow channel area ratio and the cathode flow rate on cell performance are analyzed based on the local current densities, oxygen flow rates and liquid water concentrations inside the cell. (author)

  17. Induced Differentiation of Adipose-derived Stromal Cells into Myoblasts

    Institute of Scientific and Technical Information of China (English)

    吴桂珠; 郑秀; 江忠清; 王金华; 宋岩峰

    2010-01-01

    This study aimed to induce the differentiation of isolated and purified adipose-derived stromal cells(ADSCs) into myoblasts,which may provide a new strategy for tissue engineering in patients with stress urinary incontinence(SUI).ADSCs,isolated and cultured ex vivo,were identified by flow cytometry and induced to differentiate into myoblasts in the presence of an induction solution consisting of DMEM supplemented with 5-azacytidine(5-aza),5% FBS,and 5% horse serum.Cellular morphology was observed under an i...

  18. Virus-induced non-specific signals cause cell cycle progression of primed CD8(+) T cells but do not induce cell differentiation

    DEFF Research Database (Denmark)

    Ørding Andreasen, Susanne; Christensen, Jan Pravsgaard; Marker, O;

    1999-01-01

    with known specificity and priming history in an environment also containing a normal heterogeneous CD8(+) population which served as an intrinsic control. Three parameters of T cell activation were analyzed: cell cycle progression, phenotypic conversion and cytolytic activity. Following injection of the IFN......In this report the significance of virus-induced non-specific T cell activation was re-evaluated using transgenic mice in which about half of the CD8(+) T cells expressed a TCR specific for amino acids 33-41 of lymphocytic choriomeningitis virus glycoprotein I. This allowed tracing of cells...... inducer poly(I:C), proliferation of memory (CD44(hi)) CD8(+) T cells but no phenotypic or functional activation was observed. Following injection of an unrelated virus [vesicular stomatitis virus (VSV)], naive TCR transgenic cells did not become significantly activated with respect to any...

  19. Activation of intracellular angiotensin AT₂ receptors induces rapid cell death in human uterine leiomyosarcoma cells.

    Science.gov (United States)

    Zhao, Yi; Lützen, Ulf; Fritsch, Jürgen; Zuhayra, Maaz; Schütze, Stefan; Steckelings, Ulrike M; Recanti, Chiara; Namsoleck, Pawel; Unger, Thomas; Culman, Juraj

    2015-05-01

    The presence of angiotensin type 2 (AT₂) receptors in mitochondria and their role in NO generation and cell aging were recently demonstrated in various human and mouse non-tumour cells. We investigated the intracellular distribution of AT₂ receptors including their presence in mitochondria and their role in the induction of apoptosis and cell death in cultured human uterine leiomyosarcoma (SK-UT-1) cells and control human uterine smooth muscle cells (HutSMC). The intracellular levels of the AT₂ receptor are low in proliferating SK-UT-1 cells but the receptor is substantially up-regulated in quiescent SK-UT-1 cells with high densities in mitochondria. Activation of the cell membrane AT₂ receptors by a concomitant treatment with angiotensin II and the AT₁ receptor antagonist, losartan, induces apoptosis but does not affect the rate of cell death. We demonstrate for the first time that the high-affinity, non-peptide AT₂ receptor agonist, Compound 21 (C21), penetrates the cell membrane of quiescent SK-UT-1 cells, activates intracellular AT₂ receptors and induces rapid cell death; approximately 70% of cells died within 24 h. The cells, which escaped cell death, displayed activation of the mitochondrial apoptotic pathway, i.e. down-regulation of the Bcl-2 protein, induction of the Bax protein and activation of caspase-3. All quiescent SK-UT-1 cells died within 5 days after treatment with a single dose of C21. C21 was devoid of cytotoxic effects in proliferating SK-UT-1 cells and in quiescent HutSMC. Our results point to a new, unique approach enabling the elimination non-cycling uterine leiomyosarcoma cells providing that they over-express the AT₂ receptor.

  20. UVC-induced stress granules in mammalian cells.

    Directory of Open Access Journals (Sweden)

    Mohamed Taha Moutaoufik

    Full Text Available Stress granules (SGs are well characterized cytoplasmic RNA bodies that form under various stress conditions. We have observed that exposure of mammalian cells in culture to low doses of UVC induces the formation of discrete cytoplasmic RNA granules that were detected by immunofluorescence staining using antibodies to RNA-binding proteins. UVC-induced cytoplasmic granules are not Processing Bodies (P-bodies and are bone fide SGs as they contain TIA-1, TIA-1/R, Caprin1, FMRP, G3BP1, PABP1, well known markers, and mRNA. Concomitant with the accumulation of the granules in the cytoplasm, cells enter a quiescent state, as they are arrested in G1 phase of the cell cycle in order to repair DNA damages induced by UVC irradiation. This blockage persists as long as the granules are present. A tight correlation between their decay and re-entry into S-phase was observed. However the kinetics of their formation, their low number per cell, their absence of fusion into larger granules, their persistence over 48 hours and their slow decay, all differ from classical SGs induced by arsenite or heat treatment. The induction of these SGs does not correlate with major translation inhibition nor with phosphorylation of the α subunit of eukaryotic translation initiation factor 2 (eIF2α. We propose that a restricted subset of mRNAs coding for proteins implicated in cell cycling are removed from the translational apparatus and are sequestered in a repressed form in SGs.

  1. Tangeretin induces cell cycle arrest and apoptosis through upregulation of PTEN expression in glioma cells.

    Science.gov (United States)

    Ma, Li-Li; Wang, Da-Wei; Yu, Xu-Dong; Zhou, Yan-Ling

    2016-07-01

    Tangeretin (TANG), present in peel of citrus fruits, has been shown to various medicinal properties such as chemopreventive and neuroprotective. However, the chemopreventive effect of TANG on glioblastoma cells has not been examined. The present study was designed to explore the anticancer potential of TANG in glioblastoma cells and to investigate the related mechanism. Human glioblastoma U-87MG and LN-18 cells were treated with 45μM concentration of TANG and cell growth was measured by MTT assay. The cell cycle distribution and cell death were measured by flow cytometry. The expression of cell cycle and apoptosis related genes were analyzed by quantitative RT-PCR and western blot. The cells treated with TANG were significantly increased cell growth suppression and cell death effects than vehicle treated cells. Further, TANG treatment increases G2/M arrest and apoptosis by modulating PTEN and cell-cycle regulated genes such as cyclin-D and cdc-2 mRNA and protein expressions. Moreover, the ability of TANG to decrease cell growth and to induce cell death was compromised when PTEN was knockdown by siRNA. Taken together, the chemopreventive effect of TANG is associated with regulation of cell-cycle and apoptosis in glioblastoma, thereby attenuating glioblastoma cell growth. Hence, the present findings suggest that TANG may be a therapeutic agent for glioblastoma treatment.

  2. Apigenin induces autophagic cell death in human papillary thyroid carcinoma BCPAP cells.

    Science.gov (United States)

    Zhang, Li; Cheng, Xian; Gao, Yanyan; Zheng, Jie; Xu, Qiang; Sun, Yang; Guan, Haixia; Yu, Huixin; Sun, Zhen

    2015-11-01

    Apigenin, abundantly present in fruits and vegetables, is recognized as a flavonoid with anti-inflammatory, antioxidant and anticancer properties. In this study, we first investigated the anti-neoplastic effects of apigenin on papillary thyroid carcinoma (PTC) cell line BCPAP cells. Our results show that apigenin inhibited the viability of BCPAP cells in a dose-dependent manner. A large body of evidence demonstrates that autophagy contributes to cell death in certain contexts. In the present study, autophagy was induced by apigenin treatment in BCPAP cells, as evidenced by Beclin-1 accumulation, conversion of LC3 protein, p62 degradation as well as the significantly increased formation of acidic vesicular organelles (AVOs) compared to the control group. 3-MA, an autophagy inhibitor, rescued the cells from apigenin-induced cell death. Notably, apigenin enhanced production of reactive oxygen species (ROS), and subsequent induction of significant DNA damage as monitored by the TUNEL assay. In addition, apigenin treatment caused a significant accumulation of cells in the G2/M phase via down-regulation of Cdc25C expression. Our findings reveal that apigenin inhibits papillary thyroid cancer cell viability by the stimulation of reactive oxygen species (ROS) production, induction of DNA damage, leading to G2/M cell cycle arrest followed by autophagic cell death. Thus, our results provide new insights into the molecular mechanisms underlying apigenin-mediated autophagic cell death and suggest apigenin as a potential chemotherapeutic agent which is able to fight against papillary thyroid cancer.

  3. HAIR CELL-LIKE CELL GENERATION INDUCED BY NATURE CULTURE OF ADULT RAT AUDITORY EPITHELIUM

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Hair cells are the mechanosensory cells thatconvert sound and motion signals into electrical i m-pulses in cochlear and vestibular end organs of innerear.Although mature mammals nor mally do notgenerate new hair cells,recentin vivoandin vitrostudies have demonstrated mitotic activity and i m-mature-looking hair cells in mammalian vestibularepithelia after exposure to ototoxic drugs[1-3],sug-gesting that vestibular hair cell regeneration inmammals may be inducible.However,the possibil-ity of auditory hair ce...

  4. Sensing lymphoma cells based on a cell-penetrating/apoptosis-inducing/electron-transfer peptide probe

    Energy Technology Data Exchange (ETDEWEB)

    Sugawara, Kazuharu, E-mail: kzsuga@maebashi-it.ac.jp [Maebashi Institute of Technology, Gunma 371-0816 (Japan); Shinohara, Hiroki; Kadoya, Toshihiko [Maebashi Institute of Technology, Gunma 371-0816 (Japan); Kuramitz, Hideki [Department of Environmental Biology and Chemistry, Graduate School of Science and Engineering for Research, University of Toyama, Toyama 930-8555 (Japan)

    2016-06-14

    To electrochemically sense lymphoma cells (U937), we fabricated a multifunctional peptide probe that consists of cell-penetrating/apoptosis-inducing/electron-transfer peptides. Electron-transfer peptides derive from cysteine residue combined with the C-terminals of four tyrosine residues (Y{sub 4}). A peptide whereby Y{sub 4}C is bound to the C-terminals of protegrin 1 (RGGRLCYCRRRFCVCVGR-NH{sub 2}) is known to be an apoptosis-inducing agent against U937 cells, and is referred to as a peptide-1 probe. An oxidation response of the peptide-1 probe has been observed due to a phenolic hydroxyl group, and this response is decreased by the uptake of the peptide probe into the cells. To improve the cell membrane permeability against U937 cells, the RGGR at the N-terminals of the peptide-1 probe was replaced by RRRR (peptide-2 probe). In contrast, RNRCKGTDVQAWY{sub 4}C (peptide-3 probe), which recognizes ovalbumin, was constructed as a control. Compared with the other probes, the change in the peak current of the peptide-2 probe was the greatest at low concentrations and occurred in a short amount of time. Therefore, the cell membrane permeability of the peptide-2 probe was increased based on the arginine residues and the apoptosis-inducing peptides. The peak current was linear and ranged from 100 to 1000 cells/ml. The relative standard deviation of 600 cells/ml was 5.0% (n = 5). Furthermore, the membrane permeability of the peptide probes was confirmed using fluorescent dye. - Highlights: • We constructed a multifunctional peptide probe for the electrochemical sensing of lymphoma cells. • The peptide probe consists of cell-penetrating/apoptosis-inducing/electron-transfer peptides. • The electrode response of the peptide probe changes due to selective uptake into the cells.

  5. Induction of Skin-Derived Precursor Cells from Human Induced Pluripotent Stem Cells

    Science.gov (United States)

    Sugiyama-Nakagiri, Yoriko; Fujimura, Tsutomu; Moriwaki, Shigeru

    2016-01-01

    The generation of full thickness human skin from dissociated cells is an attractive approach not only for treating skin diseases, but also for treating many systemic disorders. However, it is currently not possible to obtain an unlimited number of skin dermal cells. The goal of this study was to develop a procedure to produce skin dermal stem cells from induced pluripotent stem cells (iPSCs). Skin-derived precursor cells (SKPs) were isolated as adult dermal precursors that could differentiate into both neural and mesodermal progenies and could reconstitute the dermis. Thus, we attempted to generate SKPs from iPSCs that could reconstitute the skin dermis. Human iPSCs were initially cultured with recombinant noggin and SB431542, an inhibitor of activin/nodal and TGFβ signaling, to induce neural crest progenitor cells. Those cells were then treated with SKP medium that included CHIR99021, a WNT signal activator. The induction efficacy from neural crest progenitor cells to SKPs was more than 97%. No other modifiers tested were able to induce those cells. Those human iPSC-derived SKPs (hiPSC-SKPs) showed a similar gene expression signature to SKPs isolated from human skin dermis. Human iPSC-SKPs differentiated into neural and mesodermal progenies, including adipocytes, skeletogenic cell types and Schwann cells. Moreover, they could be induced to follicular type keratinization when co-cultured with human epidermal keratinocytes. We here provide a new efficient protocol to create human skin dermal stem cells from hiPSCs that could contribute to the treatment of various skin disorders. PMID:27992514

  6. Adipose-derived stromal cells inhibit prostate cancer cell proliferation inducing apoptosis

    Energy Technology Data Exchange (ETDEWEB)

    Takahara, Kiyoshi [Department of Urology, Faculty of Medicine, Osaka Medical College, Osaka (Japan); Ii, Masaaki, E-mail: masaii@art.osaka-med.ac.jp [Department of Pharmacology, Faculty of Medicine, Osaka Medical College, Osaka (Japan); Inamoto, Teruo; Komura, Kazumasa; Ibuki, Naokazu; Minami, Koichiro; Uehara, Hirofumi; Hirano, Hajime; Nomi, Hayahito; Kiyama, Satoshi [Department of Urology, Faculty of Medicine, Osaka Medical College, Osaka (Japan); Asahi, Michio [Department of Pharmacology, Faculty of Medicine, Osaka Medical College, Osaka (Japan); Azuma, Haruhito [Department of Urology, Faculty of Medicine, Osaka Medical College, Osaka (Japan)

    2014-04-18

    Highlights: • AdSC transplantation exhibits inhibitory effect on tumor progressions of PCa cells. • AdSC-induced PCa cell apoptosis may occur via the TGF-β signaling pathway. • High expression of the TGF-β1 gene in AdSCs. - Abstract: Mesenchymal stem cells (MSCs) have generated a great deal of interest in the field of regenerative medicine. Adipose-derived stromal cells (AdSCs) are known to exhibit extensive proliferation potential and can undergo multilineage differentiation, sharing similar characteristics to bone marrow-derived MSCs. However, as the effect of AdSCs on tumor growth has not been studied sufficiently, we assessed the degree to which AdSCs affect the proliferation of prostate cancer (PCa) cell. Human AdSCs exerted an inhibitory effect on the proliferation of androgen-responsive (LNCaP) and androgen-nonresponsive (PC3) human PCa cells, while normal human dermal fibroblasts (NHDFs) did not, and in fact promoted PCa cell proliferation to a degree. Moreover, AdSCs induced apoptosis of LNCaP cells and PC3 cells, activating the caspase3/7 signaling pathway. cDNA microarray analysis suggested that AdSC-induced apoptosis in both LNCaP and PC3 cells was related to the TGF-β signaling pathway. Consistent with our in vitro observations, local transplantation of AdSCs delayed the growth of tumors derived from both LNCaP- and PC3-xenografts in immunodeficient mice. This is the first preclinical study to have directly demonstrated that AdSC-induced PCa cell apoptosis may occur via the TGF-β signaling pathway, irrespective of androgen-responsiveness. Since autologous AdSCs can be easily isolated from adipose tissue without any ethical concerns, we suggest that therapy with these cells could be a novel approach for patients with PCa.

  7. Chemical engineering of mesenchymal stem cells to induce a cell rolling response.

    Science.gov (United States)

    Sarkar, Debanjan; Vemula, Praveen Kumar; Teo, Grace S L; Spelke, Dawn; Karnik, Rohit; Wee, Le Y; Karp, Jeffrey M

    2008-11-19

    Covalently conjugated sialyl Lewis X (SLeX) on the mesenchymal stem cell (MSC) surface through a biotin-streptavidin bridge imparts leukocyte-like rolling characteristics without altering the cell phenotype and the multilineage differentiation potential. We demonstrate that the conjugation of SLeX on the MSC surface is stable, versatile, and induces a robust rolling response on P-selectin coated substrates. These results indicate the potential to increase the targeting efficiency of any cell type to specific tissue.

  8. Changes in size and shape of auditory hair cells in vivo during noise-induced temporary threshold shift.

    Science.gov (United States)

    Dew, L A; Owen, R G; Mulroy, M J

    1993-03-01

    In this study we describe changes in the size and shape of auditory hair cells of the alligator lizard in vivo during noise-induced temporary threshold shift. These changes consist of a decrease in cell volume, a decrease in cell length and an increase in cell width. We speculate that these changes are due to relaxation of cytoskeletal contractile elements and osmotic loss of intracellular water. We also describe a decrease in the surface area of the hair cell plasmalemma, and speculate that it is related to the endocytosis and intracellular accumulation of cell membrane during synaptic vesicle recycling. Finally we describe an increase in the endolymphatic surface area of the hair cell, and speculate that this could alter the micromechanics of the stereociliary tuft to attenuate the effective stimulus.

  9. Antibody-targeting of steady state dendritic cells induces tolerance mediated by regulatory T cells

    Directory of Open Access Journals (Sweden)

    Karsten eMahnke

    2016-02-01

    Full Text Available Dendritic cells (DCs are often defined as pivotal inducers of immunity, but these proinflammatory properties only develop after stimulation or ex vivo manipulation of DCs. Under non-inflammatory conditions in vivo, DCs are embedded into a tissue environment and encounter a plethora of self-antigens derived from apoptotic material. This material is transported to secondary lymphoid organs. As DCs maintain their non-activated phenotype in a sterile tissue environment, interaction with T cells will induce rather regulatory T cells (Treg than effector T cells. Thus, DCs are not only inducers of immunity but are also critical for maintenance of peripheral tolerance. Therapeutical intervention for the induction of long lasting tolerance in several autoimmune conditions may therefore be possible by manipulating DC activation and/or targeting of DCs in their natural tissue environment.

  10. Changes induced by sea level rise on network properties of restoration areas

    Science.gov (United States)

    Jiménez, Mirian; Castanedo, Sonia; Zhou, Zeng; Coco, Giovanni; Medina, Raúl

    2015-04-01

    Human actions have been reducing the natural domain of estuarine systems for centuries. In the past, estuaries were perceived as unhealthy areas, source of diseases, which were adapted to human use by drainage and heavy engineering. Our current understanding shows that estuaries are not sources of disease, but rich ecosystems that cover important ecosystem functions. They need to be restored to their natural state. However, restoration actions may induce morphological changes that may change the estuary current behavior. It is thus of the utmost importance to understand the morphodynamic changes induced by restoration actions, more so when the final aim is to predict these changes. Dikes have been the most used mean to enclose and drain areas of estuaries. In this work, we focus our attention on dike removal as a means to restore the areas enclosed by these dikes. Dikes may be removed completely, or only partially (opening one or several breaches), to allow the tidal flow to enter into the area to be restored. Morphodynamic effects of dike removal are simulated numerically using Delft3d. Different dike removal configurations are studied and their effect on the recovery of the estuary quantified. Estuarine tidal networks are characterized by means of a new approach that links network connectivity to the spatial hydrodynamic fields developed in the estuary. The impact of different restorations strategies in the drainage properties of the network has been studied in the short term (5 -10 years) and in the long term (100 years) allowing the connectivity to evolve with time. Results show, for different scenarios, differences not only in the spatial distribution of the tidal network but also in statistical characteristics after different dike removal actions. The new distribution of channels will have implications for the location of the tidal flats, flood patterns and thus biological environments within the tidal networks. These changes in the morphological properties

  11. Solar cell evaluation using electron beam induced current with the large chamber scanning electron microscope

    Science.gov (United States)

    Wink, Tara; Kintzel, Edward; Marienhoff, Peter; Klein, Martin

    2012-02-01

    An initial study using electron beam induced current (EBIC) to evaluate solar cells has been carried out with the large chamber scanning electron microscope (LC-SEM) at the Western Kentucky University Nondestructive Analysis Center. EBIC is a scanning electron microscope technique used for the characterization of semiconductors. To facilitate our studies, we developed a Solar Amplification System (SASY) for analyzing current distribution and defects within a solar cell module. Preliminary qualitative results will be shown for a solar cell module that demonstrates the viability of the technique using the LC-SEM. Quantitative EBIC experiments will be carried out to analyze defects and minority carrier properties. Additionally, a well-focused spot of light from an LED mounted at the side of the SEM column will scan the same area of the solar cell using the LC-SEM positioning system. SASY will then output the solar efficiency to be compared with the minority carrier properties found using EBIC.

  12. Culture supernatants from V. cholerae O1 ElTor strains isolated from different geographic areas induce cell vacuolation and cytotoxicity Cepas de V. cholerae O1 biotipo ElTor aisladas de diferente origen geográfico inducen vacuolización celular y citotoxicidad

    Directory of Open Access Journals (Sweden)

    Jorge E Vidal

    2009-02-01

    Full Text Available OBJECTIVE: To investigate whether the HlyA-induced vacuolating effect is produced by V. cholerae O1 ElTor strains isolated from different geographic origins, including Mexico. MATERIAL AND METHODS: Supernatant-induced haemolysis, vacuolating activity and cytotoxicity in Vero cells were recorded. PCR, RFLP analysis and molecular cloning were performed. RESULTS: All ElTor strains analyzed induced cellular vacuolation. Ribotype 2 strains isolates from the U.S. gulf coast yielded the highest titer of vacuolating activity. Eight of nine strains were haemolytic, while all strains were PCR positive for the hlyA gene. We cloned the hlyA gene from two ElTor strains, a toxigenic (2514-88, ctxAB+ and a non-toxigenic Mexican strain (CM 91-3, ctxAB-. Supernatant from those recombinant E. coli strains induced haemolysis, cell vacuolation and cytotoxicity. RFLP-PCR analysis revealed similarities in the hlyA gene from all strains tested. CONCLUSION: The HlyA-induced vacuolating effect is a widespread phenotype of epidemic V. cholerae O1 ElTor strains.OBJETIVO: Analizar el efecto vacuolizante de cepas de V. cholerae O1 ElTor aisladas de diferente origen geográfico, incluyendo México. MATERIAL Y MÉTODOS: Se realizaron pruebas de hemolisis, vacuolización y citotoxicidad en células Vero, así como PCR, análisis por RFLP y clonación molecular. RESULTADOS: Todas las cepas indujeron el efecto vacuolizante. Las cepas del ribotipo 2, aisladas de las costas del Golfo en Estados Unidos, presentaron títulos altos de vacuolización. El gen hlyA fue amplificado en las nueve cepas mediante PCR, aunque sólo ocho fueron hemolíticas. Se clonó el gen hlyA de una cepa toxigénica (2514-88, ctxAB+ y de una cepa no toxigénica aislada en México (CM 91-3, ctxAB-. El sobrenadante de las clonas recombinantes indujo hemólisis, efecto vacuolizante y citotoxicidad. El RFLP mostró alta similitud del gen hlyA de las cepas estudiadas. CONCLUSIÓN: El efecto vacuolizante es un

  13. Contribution of cells derived from the area pellucida to extraembryonic mesodermal cell lineages in heterospecific quail chick blastodermal chimeras.

    Science.gov (United States)

    Karagenç, Levent; Sandikci, Mustafa

    2013-01-01

    The current study has two main objectives: first, to determine if cells derived from the area pellucida are able to populate extraembryonic membranes, and second, to determine if donor cells have the potential to differentiate to endothelial (EC) and hematopoietic cells (HC) in the yolk sac and allantois, the two extraembryonic membranes functioning as hematopoietic organs in the avian embryo. To this end, quail chick chimeras were constructed by transferring dissociated cells from the areae pellucidae of the stage X-XII (EG&K) quail embryo into the subgerminal cavity of the unincubated chick blastoderm. The distribution of quail cells in the allantois, yolk sac, amnion, and chorion of resulting putative chimeras was examined using quail cell-specific antibody against a perinuclear antigen (QCPN) after 6 days of incubation. The presence of EC, HC, and smooth muscle cells among the QCPN(+) donor cells was examined using QH-1, a quail-specific marker identifying HC and EC and an anti-α-smooth muscle actin antibody. Evidence gathered in the present study demonstrates that quail cells derived from the areae pellucidae are able to populate all of the extraembryonic membranes of resulting heterospecific quail chick chimeras and, most importantly, give rise to HC, EC, and smooth muscle cells, all of the three main mesodermal lineages derived from the posterior mesoderm both in the yolk sac and allantois.

  14. Involvement of ethylene and lipid signalling in cadmium-induced programmed cell death in tomato suspension cells

    NARCIS (Netherlands)

    Iakimova, E.T.; Kapchina-Toteva, V.M.; Laarhoven, L.J.; Harren, F.; Woltering, E.J.

    2006-01-01

    Cadmium-induced cell death was studied in suspension-cultured tomato (Lycopersicon esculentum Mill.) cells (line MsK8) treated with CdSO4. Within 24 h, cadmium treatment induced cell death in a concentration-dependent manner. Cell cultures showed recovery after 2¿3 days which indicates the existence

  15. Involvement of ethylene and lipid signalling in cadmium-induced programmed cell death in tomato suspension cells

    NARCIS (Netherlands)

    Yakimova, E.T.; Kapchina-Toteva, V.M.; Laarhoven, L.J.J.; Harren, F.J.M.; Woltering, E.J.

    2006-01-01

    Cadmium-induced cell death was studied in suspension-cultured tomato (Lycopersicon esculentum Mill.) cells (line MsK8) treated with CdSO4. Within 24 h, cadmium treatment induced cell death in a concentration-dependent manner. Cell cultures showed recovery after 23 days which indicates the existence

  16. Collective cancer cell invasion induced by coordinated contractile stresses.

    Science.gov (United States)

    Jimenez Valencia, Angela M; Wu, Pei-Hsun; Yogurtcu, Osman N; Rao, Pranay; DiGiacomo, Josh; Godet, Inês; He, Lijuan; Lee, Meng-Horng; Gilkes, Daniele; Sun, Sean X; Wirtz, Denis

    2015-12-22

    The physical underpinnings of fibrosarcoma cell dissemination from a tumor in a surrounding collagen-rich matrix are poorly understood. Here we show that a tumor spheroid embedded in a 3D collagen matrix exerts large contractile forces on the matrix before invasion. Cell invasion is accompanied by complex spatially and temporally dependent patterns of cell migration within and at the surface of the spheroids that are fundamentally different from migratory patterns of individual fibrosarcoma cells homogeneously distributed in the same type of matrix. Cells display a continuous transition from a round morphology at the spheroid core, to highly aligned elongated morphology at the spheroid periphery, which depends on both β1-integrin-based cell-matrix adhesion and myosin II/ROCK-based cell contractility. This isotropic-to-anisotropic transition corresponds to a shift in migration, from a slow and unpolarized movement at the core, to a fast, polarized and persistent one at the periphery. Our results also show that the ensuing collective invasion of fibrosarcoma cells is induced by anisotropic contractile stresses exerted on the surrounding matrix.

  17. Hematopoietic development from human induced pluripotent stem cells.

    Science.gov (United States)

    Lengerke, Claudia; Grauer, Matthias; Niebuhr, Nina I; Riedt, Tamara; Kanz, Lothar; Park, In-Hyun; Daley, George Q

    2009-09-01

    A decade of research on human embryonic stem cells (ESC) has paved the way for the discovery of alternative approaches to generating pluripotent stem cells. Combinatorial overexpression of a limited number of proteins linked to pluripotency in ESC was recently found to reprogram differentiated somatic cells back to a pluripotent state, enabling the derivation of isogenic (patient-specific) pluripotent stem cell lines. Current research is focusing on improving reprogramming protocols (e.g., circumventing the use of retroviral technology and oncoproteins), and on methods for differentiation into transplantable tissues of interest. In mouse ESC, we have previously shown that the embryonic morphogens BMP4 and Wnt3a direct blood formation via activation of Cdx and Hox genes. Ectopic expression of Cdx4 and HoxB4 enables the generation of mouse ESC-derived hematopoietic stem cells (HSC) capable of multilineage reconstitution of lethally irradiated adult mice. Here, we explore hematopoietic development from human induced pluripotent stem (iPS) cells generated in our laboratory. Our data show robust differentiation of iPS cells to mesoderm and to blood lineages, as shown by generation of CD34(+)CD45(+) cells, hematopoietic colony activity, and gene expression data, and suggest conservation of blood patterning pathways between mouse and human hematopoietic development.

  18. Characterization of nicardipine hydrochloride-induced cell injury in human vascular endothelial cells.

    Science.gov (United States)

    Ochi, Masanori; Kawai, Yoshiko; Tanaka, Yoshiyuki; Toyoda, Hiromu

    2015-02-01

    Nicardipine hydrochloride (NIC), a dihydropyridine calcium-channel blocking agent, has been widely used for the treatment of hypertension. Especially, nicardipine hydrochloride injection is used as first-line therapy for emergency treatment of abnormally high blood pressure. Although NIC has an attractive pharmacological profile, one of the dose-limiting factors of NIC is severe peripheral vascular injury after intravenous injection. The goal of this study was to better understand and thereby reduce NIC-mediated vascular injury. Here, we investigated the mechanism of NIC-induced vascular injury using human dermal microvascular endothelial cells (HMVECs). NIC decreased cell viability and increased percent of dead cells in a dose-dependent manner (10-30 μg/mL). Although cell membrane injury was not significant over 9 hr exposure, significant changes of cell morphology and increases in vacuoles in HMVECs were observed within 30 min of NIC exposure (30 μg/mL). Autophagosome labeling with monodansylcadaverine revealed increased autophagosomes in the NIC-treated cells, whereas caspase 3/7 activity was not increased in the NIC-treated cells (30 μg/mL). Additionally, NIC-induced reduction of cell viability was inhibited by 3-methyladenine, an inhibitor of autophagosome formation. These findings suggest that NIC causes severe peripheral venous irritation via induction of autophagic cell death and that inhibition of autophagy could contribute to the reduction of NIC-induced vascular injury.

  19. Generation of glycosylphosphatidylinositol anchor protein-deficient blood cells from human induced pluripotent stem cells.

    Science.gov (United States)

    Yuan, Xuan; Braunstein, Evan M; Ye, Zhaohui; Liu, Cyndi F; Chen, Guibin; Zou, Jizhong; Cheng, Linzhao; Brodsky, Robert A

    2013-11-01

    PIG-A is an X-linked gene required for the biosynthesis of glycosylphosphatidylinositol (GPI) anchors; thus, PIG-A mutant cells have a deficiency or absence of all GPI-anchored proteins (GPI-APs). Acquired mutations in hematopoietic stem cells result in the disease paroxysmal nocturnal hemoglobinuria, and hypomorphic germline PIG-A mutations lead to severe developmental abnormalities, seizures, and early death. Human induced pluripotent stem cells (iPSCs) can differentiate into cell types derived from all three germ layers, providing a novel developmental system for modeling human diseases. Using PIG-A gene targeting and an inducible PIG-A expression system, we have established, for the first time, a conditional PIG-A knockout model in human iPSCs that allows for the production of GPI-AP-deficient blood cells. PIG-A-null iPSCs were unable to generate hematopoietic cells or any cells expressing the CD34 marker and were defective in generating mesodermal cells expressing KDR/VEGFR2 (kinase insert domain receptor) and CD56 markers. In addition, PIG-A-null iPSCs had a block in embryonic development prior to mesoderm differentiation that appears to be due to defective signaling through bone morphogenetic protein 4. However, early inducible PIG-A transgene expression allowed for the generation of GPI-AP-deficient blood cells. This conditional PIG-A knockout model should be a valuable tool for studying the importance of GPI-APs in hematopoiesis and human development.

  20. Effect of Induced Pluripotent Stem Cell Technology in Blood Banking.

    Science.gov (United States)

    Focosi, Daniele; Pistello, Mauro

    2016-03-01

    Population aging has imposed cost-effective alternatives to blood donations. Artificial blood is still at the preliminary stages of development, and the need for viable cells seems unsurmountable. Because large numbers of viable cells must be promptly available for clinical use, stem cell technologies, expansion, and banking represent ideal tools to ensure a regular supply. Provided key donors can be identified, induced pluripotent stem cell (iPSC) technology could pave the way to a new era in transfusion medicine, just as it is already doing in many other fields of medicine. The present review summarizes the current state of research on iPSC technology in the field of blood banking, highlighting hurdles, and promises.

  1. IFN-inducible GTPases in host cell defense.

    Science.gov (United States)

    Kim, Bae-Hoon; Shenoy, Avinash R; Kumar, Pradeep; Bradfield, Clinton J; MacMicking, John D

    2012-10-18

    From plants to humans, the ability to control infection at the level of an individual cell-a process termed cell-autonomous immunity-equates firmly with survival of the species. Recent work has begun to unravel this programmed cell-intrinsic response and the central roles played by IFN-inducible GTPases in defending the mammalian cell's interior against a diverse group of invading pathogens. These immune GTPases regulate vesicular traffic and protein complex assembly to stimulate oxidative, autophagic, membranolytic, and inflammasome-related antimicrobial activities within the cytosol, as well as on pathogen-containing vacuoles. Moreover, human genome-wide association studies and disease-related transcriptional profiling have linked mutations in the Immunity-Related GTPase M (IRGM) locus and altered expression of guanylate binding proteins (GBPs) with tuberculosis susceptibility and Crohn's colitis.

  2. Activation-induced cell death in B lymphocytes

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Upon encountering the antigen (Ag), the immune system can either develop a specific immune response or enter a specific state of unresponsiveness, tolerance. The response of B cells to their specific Ag can be activation and proliferation, leading to the immune response, or anergy and activation-induced cell death (AICD), leading to tolerance. AICD in B lymphocytes is a highly regulated event initiated by crosslinking of the B cell receptor (BCR). BCR engagement initiates several signaling events such as activation of PLCγ, Ras, and PI3K, which generally speaking, lead to survival However, in the absence of survival signals (CD40 or IL-4R engagement), BCR crosslinking can also promote apoptotic signal transduction pathways such as activation of effector caspases, expression of pro-apoptotic genes, and inhibition of pro-survival genes. The complex interplay between survival and death signals determines the B cell fate and, consequently, the immune response.

  3. Induced pluripotent stem cells in dermatology: potentials, advances, and limitations.

    Science.gov (United States)

    Bilousova, Ganna; Roop, Dennis R

    2014-11-03

    The discovery of methods for reprogramming adult somatic cells into induced pluripotent stem cells (iPSCs) has raised the possibility of producing truly personalized treatment options for numerous diseases. Similar to embryonic stem cells (ESCs), iPSCs can give rise to any cell type in the body and are amenable to genetic correction by homologous recombination. These ESC properties of iPSCs allow for the development of permanent corrective therapies for many currently incurable disorders, including inherited skin diseases, without using embryonic tissues or oocytes. Here, we review recent progress and limitations of iPSC research with a focus on clinical applications of iPSCs and using iPSCs to model human diseases for drug discovery in the field of dermatology.

  4. Generation of a Drug-inducible Reporter System to Study Cell Reprogramming in Human Cells*

    Science.gov (United States)

    Ruiz, Sergio; Panopoulos, Athanasia D.; Montserrat, Nuria; Multon, Marie-Christine; Daury, Aurélie; Rocher, Corinne; Spanakis, Emmanuel; Batchelder, Erika M.; Orsini, Cécile; Deleuze, Jean-François; Izpisua Belmonte, Juan Carlos

    2012-01-01

    Reprogramming of somatic cells into induced pluripotent stem cells is achieved by the expression of defined transcription factors. In the last few years, reprogramming strategies on the basis of doxycycline-inducible lentiviruses in mouse cells became highly powerful for screening purposes when the expression of a GFP gene, driven by the reactivation of endogenous stem cell specific promoters, was used as a reprogramming reporter signal. However, similar reporter systems in human cells have not been generated. Here, we describe the derivation of drug-inducible human fibroblast-like cell lines that express different subsets of reprogramming factors containing a GFP gene under the expression of the endogenous OCT4 promoter. These cell lines can be used to screen functional substitutes for reprogramming factors or modifiers of reprogramming efficiency. As a proof of principle of this system, we performed a screening of a library of pluripotent-enriched microRNAs and identified hsa-miR-519a as a novel inducer of reprogramming efficiency. PMID:23019325

  5. New castanospermine glycoside analogues inhibit breast cancer cell proliferation and induce apoptosis without affecting normal cells.

    Directory of Open Access Journals (Sweden)

    Ghada Allan

    Full Text Available sp²-Iminosugar-type castanospermine analogues have been shown to exhibit anti-tumor activity. However, their effects on cell proliferation and apoptosis and the molecular mechanism at play are not fully understood. Here, we investigated the effect of two representatives, namely the pseudo-S- and C-octyl glycoside 2-oxa-3-oxocastanospermine derivatives SO-OCS and CO-OCS, on MCF-7 and MDA-MB-231 breast cancer and MCF-10A mammary normal cell lines. We found that SO-OCS and CO-OCS inhibited breast cancer cell viability in a concentration- and time-dependent manner. This effect is specific to breast cancer cells as both molecules had no impact on normal MCF-10A cell proliferation. Both drugs induced a cell cycle arrest. CO-OCS arrested cell cycle at G1 and G2/M in MCF-7 and MDA-MB-231 cells respectively. In MCF-7 cells, the G1 arrest is associated with a reduction of CDK4 (cyclin-dependent kinase 4, cyclin D1 and cyclin E expression, pRb phosphorylation, and an overexpression of p21(Waf1/Cip1. In MDA-MB-231 cells, CO-OCS reduced CDK1 but not cyclin B1 expression. SO-OCS accumulated cells in G2/M in both cell lines and this blockade was accompanied by a decrease of CDK1, but not cyclin B1 expression. Furthermore, both drugs induced apoptosis as demonstrated by the increased percentage of annexin V positive cells and Bax/Bcl-2 ratio. Interestingly, in normal MCF-10A cells the two drugs failed to modify cell proliferation, cell cycle progression, cyclins, or CDKs expression. These results demonstrate that the effect of CO-OCS and SO-OCS is triggered by both cell cycle arrest and apoptosis, suggesting that these castanospermine analogues may constitute potential anti-cancer agents against breast cancer.

  6. DNA damage responses in human induced pluripotent stem cells and embryonic stem cells.

    Directory of Open Access Journals (Sweden)

    Olga Momcilovic

    Full Text Available BACKGROUND: Induced pluripotent stem (iPS cells have the capability to undergo self-renewal and differentiation into all somatic cell types. Since they can be produced through somatic cell reprogramming, which uses a defined set of transcription factors, iPS cells represent important sources of patient-specific cells for clinical applications. However, before these cells can be used in therapeutic designs, it is essential to understand their genetic stability. METHODOLOGY/PRINCIPAL FINDINGS: Here, we describe DNA damage responses in human iPS cells. We observe hypersensitivity to DNA damaging agents resulting in rapid induction of apoptosis after γ-irradiation. Expression of pluripotency factors does not appear to be diminished after irradiation in iPS cells. Following irradiation, iPS cells activate checkpoint signaling, evidenced by phosphorylation of ATM, NBS1, CHEK2, and TP53, localization of ATM to the double strand breaks (DSB, and localization of TP53 to the nucleus of NANOG-positive cells. We demonstrate that iPS cells temporary arrest cell cycle progression in the G(2 phase of the cell cycle, displaying a lack of the G(1/S cell cycle arrest similar to human embryonic stem (ES cells. Furthermore, both cell types remove DSB within six hours of γ-irradiation, form RAD51 foci and exhibit sister chromatid exchanges suggesting homologous recombination repair. Finally, we report elevated expression of genes involved in DNA damage signaling, checkpoint function, and repair of various types of DNA lesions in ES and iPS cells relative to their differentiated counterparts. CONCLUSIONS/SIGNIFICANCE: High degrees of similarity in DNA damage responses between ES and iPS cells were found. Even though reprogramming did not alter checkpoint signaling following DNA damage, dramatic changes in cell cycle structure, including a high percentage of cells in the S phase, increased radiosensitivity and loss of DNA damage-induced G(1/S cell cycle arrest, were

  7. Hydrogen peroxide-induced changes in intracellular pH of guard cells precede stomatal closure

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Epidermal bioassay demonstrated that benzylamine,a membrane-permeable weak base,can mimick hydrogen peroxide (H2O2) to induce stomatal closure,and butyric acid,a membrane-permeable weak acid,can partly abolish the H2O2-induced stomatal closure.Confocal pH mapping with the probe 5-(and-6)-carboxy seminaphthorhodafluor-1-acetoxymethylester (SNARF-1-AM) revealed that H2O2 leads to rapid changes in cytoplasmic and vacuolar pH in guard cells of Vicia faba L,i.e.alkalinization of cytoplasmic areas occur red in parallel with a decrease of the vacuolar pH,and that butyric acid pretreatment can abolish alkalinization of cytoplasmic areas and acidification of vacuolar areas of guard cells challenged with H2O2.These results imply that the alkalinization of cytoplasm via efflux of cytosol protons into the vacuole in guard cells challenged with H2O2 is important at an early stage in the signal cascade leading to stomatal closure.

  8. The future of induced pluripotent stem cells for cardiac therapy and drug development

    OpenAIRE

    Sampaolesi, Maurilio; Thorrez, Lieven

    2011-01-01

    The field of stem cell research was revolutionized with the advent of induced pluripotent stem cells. By reprogramming somatic cells to pluripotent stem cells, most ethical concerns associated with the use of embryonic stem cells are overcome, such that many hopes from the stem cell field now seem a step closer to reality. Several methods and cell sources have been described to create induced pluripotent stem cells and we discuss their characteristics in terms of feasibility and efficiency. F...

  9. Acetaminophen induces human neuroblastoma cell death through NFKB activation.

    Directory of Open Access Journals (Sweden)

    Inmaculada Posadas

    Full Text Available 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-x(L 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.

  10. Induced pluripotent stem cells: from Nobel Prizes to clinical applications.

    Science.gov (United States)

    Rashid, S Tamir; Alexander, Graeme J M

    2013-03-01

    Advances in basic hepatology have been constrained for many years by the inability to culture primary hepatocytes in vitro, until just over five years ago when the scientific playing field was changed beyond recognition with the demonstration that human skin fibroblasts could be reprogrammed to resemble embryonic cells. The reprogrammed cells, known as induced pluripotent stem cells (iPSCs), were then shown to have the capacity to re-differentiate into almost any human cell type, including hepatocytes. The unlimited number and isogenic nature of the cells that can be generated from tiny fragments of tissue have massive implications for the study of human liver diseases in vitro. Of more immediate clinical importance were recent data demonstrating precision gene therapy on patient specific iPSCs, which opens up the real and exciting possibility of autologous hepatocyte transplantation as a substitute for allogeneic whole liver transplantation, which has been an effective approach to end-stage liver disease, but one that has now been outstripped by demand. In this review, we describe the historical development, current technology and potential clinical applications of induced pluripotency, concluding with a perspective on possible future directions in this dynamic field.

  11. Fenofibrate induces ketone body production in melanoma and glioblastoma cells

    Directory of Open Access Journals (Sweden)

    Maja M Grabacka

    2016-02-01

    Full Text Available Ketone bodies (beta-hydroxybutyrate, bHB, acetoacetate are mainly produced in the liver during prolonged fasting or starvation. bHB is a very efficient energy substrate for sustaining ATP production in peripheral tissues; importantly its consumption is preferred over glucose. However, the majority of malignant cells, particularly cancer cells of neuroectodermal origin such as glioblastoma, are not able to use ketone bodies as a source of energy. Here, we report a novel observation that fenofibrate, a synthetic peroxisome proliferator-activated receptor alpha (PPARa agonist, induces bHB production in melanoma and glioblastoma cells, as well as in neurospheres composed of nontransformed cells. Unexpectedly, this effect is not dependent on PPARa activity or its expression level. The fenofibrate-induced ketogenesis is accompanied by growth arrest and down-regulation of transketolase, but the NADP/NADPH and GSH/GSSG ratios remain unaffected. Our results reveal a new, intriguing aspect of cancer cell biology and highlight the benefits of fenofibrate as a supplement to both canonical and dietary (ketogenic therapeutic approaches against glioblastoma.

  12. Semiallogenic fusions of MSI+ tumor cells and activated B cells induce MSI-specific T cell responses

    Directory of Open Access Journals (Sweden)

    Klier Ulrike

    2011-09-01

    Full Text Available Abstract Background Various strategies have been developed to transfer tumor-specific antigens into antigen presenting cells in order to induce cytotoxic T cell responses against tumor cells. One approach uses cellular vaccines based on fusions of autologous antigen presenting cells and allogeneic tumor cells. The fusion cells combine antigenicity of the tumor cell with optimal immunostimulatory capacity of the antigen presenting cells. Microsatellite instability caused by mutational inactivation of DNA mismatch repair genes results in translational frameshifts when affecting coding regions. It has been shown by us and others that these mutant proteins lead to the presentation of immunogenic frameshift peptides that are - in principle - recognized by a multiplicity of effector T cells. Methods We chose microsatellite instability-induced frameshift antigens as ideal to test for induction of tumor specific T cell responses by semiallogenic fusions of microsatellite instable carcinoma cells with CD40-activated B cells. Two fusion clones of HCT116 with activated B cells were selected for stimulation of T cells autologous to the B cell fusion partner. Outgrowing T cells were phenotyped and tested in functional assays. Results The fusion clones expressed frameshift antigens as well as high amounts of MHC and costimulatory molecules. Autologous T cells stimulated with these fusions were predominantly CD4+, activated, and reacted specifically against the fusion clones and also against the tumor cell fusion partner. Interestingly, a response toward 6 frameshift-derived peptides (of 14 tested could be observed. Conclusion Cellular fusions of MSI+ carcinoma cells and activated B cells combine the antigen-presenting capacity of the B cell with the antigenic repertoire of the carcinoma cell. They present frameshift-derived peptides and can induce specific and fully functional T cells recognizing not only fusion cells but also the carcinoma cells. These

  13. Methods of induced pluripotent stem cells for clinicalapplication

    Institute of Scientific and Technical Information of China (English)

    Tomohisa Seki; Keiichi Fukuda

    2015-01-01

    Reprograming somatic cells using exogenetic geneexpression represents a groundbreaking step inregenerative medicine. Induced pluripotent stem cells(iPSCs) are expected to yield novel therapies withthe potential to solve many issues involving incurablediseases. In particular, applying iPSCs clinically holds thepromise of addressing the problems of immune rejectionand ethics that have hampered the clinical applicationsof embryonic stem cells. However, as iPSC research hasprogressed, new problems have emerged that need tobe solved before the routine clinical application of iPSCscan become established. In this review, we discuss thecurrent technologies and future problems of human iPSCgeneration methods for clinical use.

  14. Glutamine enhances glucose-induced mesangial cell proliferation.

    Science.gov (United States)

    Lagranha, Claudia J; Doi, Sonia Q; Pithon-Curi, Tania C; Curi, Rui; Sellitti, Donald F

    2008-05-01

    The proliferation of mesangial cells (MC) in the presence of glutamine (0-20 mM) was determined in both low (5 mM) and high (25 mM) glucose-containing medium. Glutamine in a high glucose (HG) environment increased cell proliferation in a dose-dependent manner. Inhibition of glutamine:fructose 6-phosphate amidotransferase (GFAT) and of phosphodiesterase significantly reduced glutamine-induced proliferation. Supraphysiologic levels of glutamine increase MC proliferation in a HG milieu via GFAT and cAMP-dependent pathways, suggesting that glutamine could pose a risk for diabetic nephropathy.

  15. Facilitated Anion Transport Induces Hyperpolarization of the Cell Membrane That Triggers Differentiation and Cell Death in Cancer Stem Cells.

    Science.gov (United States)

    Soto-Cerrato, Vanessa; Manuel-Manresa, Pilar; Hernando, Elsa; Calabuig-Fariñas, Silvia; Martínez-Romero, Alicia; Fernández-Dueñas, Víctor; Sahlholm, Kristoffer; Knöpfel, Thomas; García-Valverde, María; Rodilla, Ananda M; Jantus-Lewintre, Eloisa; Farràs, Rosa; Ciruela, Francisco; Pérez-Tomás, Ricardo; Quesada, Roberto

    2015-12-23

    Facilitated anion transport potentially represents a powerful tool to modulate various cellular functions. However, research into the biological effects of small molecule anionophores is still at an early stage. Here we have used two potent anionophore molecules inspired in the structure of marine metabolites tambjamines to gain insight into the effect induced by these compounds at the cellular level. We show how active anionophores, capable of facilitating the transmembrane transport of chloride and bicarbonate in model phospholipid liposomes, induce acidification of the cytosol and hyperpolarization of plasma cell membranes. We demonstrate how this combined effect can be used against cancer stem cells (CSCs). Hyperpolarization of cell membrane induces cell differentiation and loss of stemness of CSCs leading to effective elimination of this cancer cell subpopulation.

  16. Stability issues pertaining large area perovskite and dye-sensitized solar cells and modules

    Science.gov (United States)

    Castro-Hermosa, S.; Yadav, S. K.; Vesce, L.; Guidobaldi, A.; Reale, A.; Di Carlo, A.; Brown, T. M.

    2017-01-01

    Perovskite and dye-sensitized solar cells are PV technologies which hold promise for PV application. Arguably, the biggest issue facing these technologies is stability. The vast majority of studies have been limited to small area laboratory cells. Moisture, oxygen, UV light, thermal and electrical stresses are leading the degradation causes. There remains a shortage of stability investigations on large area devices, in particular modules. At the module level there exist particular challenges which can be different from those at the small cell level such as encapsulation (not only of the unit cells but of interconnections and contacts), non-uniformity of the layer stacks and unit cells, reverse bias stresses, which are important to investigate for technologies that aim for industrial acceptance. Herein we present a review of stability investigations published in the literature pertaining large area perovskite and dye-sensitized solar devices fabricated both on rigid (glass) and flexible substrates.

  17. Analysis of shallow landslides and soil erosion induced by rainfall over large areas

    Science.gov (United States)

    Cuomo, Sabatino; Della Sala, Maria

    2014-05-01

    soil initial suction. On the other hand, the source areas for erosion phenomena depend on rainfall characteristics and soil cover, with simulated eroded areas larger in autumn season. In addition, for a past event, the simulated source areas of shallow landslides are smaller than those observed in the field while the simulated eroded areas with thickness greater than 5 cm are comparable with the in-situ evidences if the analysis takes into account high rainfall intensity and a spatially variable soil cover use, thus providing a consistent interpretation of the event. References Acharya, G., Cochrane, T., Davies, T., Bowman, E. (2011). Quantifying and modeling postfailure sediment yields from laboratory-scale soil erosion and shallow landslide experiments with silty loess. Geomorphology 129, 49-58. Cascini L., Cuomo S., Della Sala M. (2011). Spatial and temporal occurrence of rainfall-induced shallow landslides of flow type: A case of Sarno-Quindici, Italy. Geomorphology, 126(1-2), 148-158. Cascini, L., Sorbino, G., Cuomo, S., Ferlisi, S. (2013). Seasonal effects of rainfall on the shallow pyroclastic deposits of the Campania region (southern Italy). Landslides, 1-14, DOI: 10.1007/s10346-013-0395-3. Cuomo S., Della Sala M. (2013). Spatially distributed analysis of shallow landslides and soil erosion induced by rainfall. (submitted to Natural Hazards). Fell, R., Corominas J., Bonnard, C., Cascini, L., Leroi E., Savage, W.Z., on behalf of the JTC-1 Joint Technical Committee on Landslides and Engineered Slopes (2008). Guidelines for landslide susceptibility, hazard and risk zoning for land use planning. Engineering Geolology, 102(3-4):85-98. Merritt, W.S., Latcher, R.A., Jakeman, A.J. (2003). A review of erosion and sediment transport models. Environmental Modelling and Software 18, 761- 799. Sorbino G., Sica C., Cascini L. (2010). Susceptibility analysis of shallow landslides source areas using physically based models. Natural Hazards, 53(2), 313-332.

  18. Breast cancer cells with acquired antiestrogen resistance are sensitized to cisplatin-induced cell death

    DEFF Research Database (Denmark)

    Yde, Christina Westmose; Gyrd-Hansen, Mads; Lykkesfeldt, Anne E

    2007-01-01

    for future breast cancer treatment. In this study, we have investigated the effect of the chemotherapeutic compound cisplatin using a panel of antiestrogen-resistant breast cancer cell lines established from the human breast cancer cell line MCF-7. We show that the antiestrogen-resistant cells...... with parental MCF-7 cells. Our data show that Bcl-2 can protect antiestrogen-resistant breast cancer cells from cisplatin-induced cell death, indicating that the reduced expression of Bcl-2 in the antiestrogen-resistant cells plays a role in sensitizing the cells to cisplatin treatment.......Antiestrogens are currently used for treating breast cancer patients who have estrogen receptor-positive tumors. However, patients with advanced disease will eventually develop resistance to the drugs. Therefore, compounds effective on antiestrogen-resistant tumors will be of great importance...

  19. Radiation-induced spindle cell sarcoma: A rare case report

    Directory of Open Access Journals (Sweden)

    Khan Mubeen

    2009-01-01

    Full Text Available Ionizing radiation has been known to induce malignant transformation in human beings. Radiation-induced sarcomas are a late sequel of radiation therapy. Most sarcomas have been reported to occur after exposure to a radiation dose of 55 Gray (Gy and above, with a dose ranging from 16 to 112 Gys. Spindle cell sarcomas, arising after radiotherapy given to treat the carcinoma of head and neck region is a very uncommon sequel. This is a rare case report of spindle cell sarcoma of left maxilla, in a 24-year-old male, occurring as a late complication of radiotherapy with Cobalt-60 given for the treatment of retinoblastoma of the left eye 21 years back.

  20. Rho1-Wnd signaling regulates loss-of-cell polarity-induced cell invasion in Drosophila.

    Science.gov (United States)

    Ma, X; Chen, Y; Zhang, S; Xu, W; Shao, Y; Yang, Y; Li, W; Li, M; Xue, L

    2016-02-18

    Both cell polarity and c-Jun N-terminal kinase (JNK) activity are essential to the maintenance of tissue homeostasis, and disruption of either is commonly seen in cancer progression. Despite the established connection between loss-of-cell polarity and JNK activation, much less is known about the molecular mechanism by which aberrant cell polarity induces JNK-mediated cell migration and tumor invasion. Here we show results from a genetic screen using an in vivo invasion model via knocking down cell polarity gene in Drosophila wing discs, and identify Rho1-Wnd signaling as an important molecular link that mediates loss-of-cell polarity-triggered JNK activation and cell invasion. We show that Wallenda (Wnd), a protein kinase of the mitogen-activated protein kinase kinase kinase family, by forming a complex with the GTPase Rho1, is both necessary and sufficient for Rho1-induced JNK-dependent cell invasion, MMP1 activation and epithelial-mesenchymal transition. Furthermore, Wnd promotes cell proliferation and tissue growth through wingless production when apoptosis is inhibited by p35. Finally, Wnd shows oncogenic cooperation with Ras(V12) to trigger tumor growth in eye discs and causes invasion into the ventral nerve cord. Together, our data not only provides a novel mechanistic insight on how cell polarity loss contributes to cell invasion, but also highlights the value of the Drosophila model system to explore human cancer biology.

  1. Advances in induced pluripotent stem cells, genomics, biomarkers, and antiplatelet therapy highlights of the year in JCTR 2013.

    Science.gov (United States)

    Barbato, Emanuele; Lara-Pezzi, Enrique; Stolen, Craig; Taylor, Angela; Barton, Paul J; Bartunek, Jozef; Iaizzo, Paul; Judge, Daniel P; Kirshenbaum, Lorrie; Blaxall, Burns C; Terzic, Andre; Hall, Jennifer L

    2014-07-01

    The Journal provides the clinician and scientist with the latest advances in discovery research, emerging technologies, preclinical research design and testing, and clinical trials. We highlight advances in areas of induced pluripotent stem cells, genomics, biomarkers, multimodality imaging, and antiplatelet biology and therapy. The top publications are critically discussed and presented along with anatomical reviews and FDA insight to provide context.

  2. Human-induced pluripotent stem cells from blood cells of healthy donors and patients with acquired blood disorders

    OpenAIRE

    2009-01-01

    Human induced pluripotent stem (iPS) cells derived from somatic cells hold promise to develop novel patient-specific cell therapies and research models for inherited and acquired diseases. We and others previously reprogrammed human adherent cells, such as postnatal fibroblasts to iPS cells, which resemble adherent embryonic stem cells. Here we report derivation of iPS cells from postnatal human blood cells and the potential of these pluripotent cells for disease modeling. Multiple human iPS ...

  3. Inhibition of autophagy induced by proteasome inhibition increases cell death in human SHG-44 glioma cells

    Institute of Scientific and Technical Information of China (English)

    Peng-fei GE; Ji-zhou ZHANG; Xiao-fei WANG; Fan-kai MENG; Wen-chen LI; Yong-xin LUAN; Feng LING; Yi-nan LUO

    2009-01-01

    Aim:The ubiquitin-proteasome system (UPS) and lysosome-dependent macroautophagy (autophagy) are two major intracellular pathways for protein degradation.Recent studies suggest that proteasome inhibitors may reduce tumor growth and activate autophagy.Due to the dual roles of autophagy in tumor cell survival and death,the effect of autophagy on the destiny of glioma cells remains unclear.In this study,we sought to investigate whether inhibition of the proteasome can induce autophagy and the effects of autophagy on the fate of human SHG-44 glioma cells.Methods:The proteasome inhibitor MG-132 was used to induce autophagy in SHG-44 glioma cells,and the effect of autophagy on the survival of SHG-44 glioma cells was investigated using an autophagy inhibitor 3-MA.Cell viability was measured by MTT assay.Apoptosis and cell cycle were detected by flow cytometry.The expression of autophagy related proteins was determined by Western blot.Results:MG-132 inhibited cell proliferation,induced cell death and cell cycle arrest at G~JM phase,and activated autophagy in SHG-44 glioma cells.The expression of autophagy-related Beclin-1 and LC3-1 was significantly up-regulated and part of LC3-1 was converted into LC3-11.However,when SHG-44 glioma cells were co-treated with MG-132 and 3-MA,the cells became less viable,but cell death and cell numbers at G2/M phase increased.Moreover,the accumulation of acidic vesicular organelles was decreased,the expression of Beclin-1 and LC3 was significantly down-regulated and the conversion of LC3-11 from LC3-1 was also inhibited.Conclusion:Inhibition of the proteasome can induce autophagy in human SHG-44 glioma cells,and inhibition of autophagy increases cell death.This discovery may shed new light on the effect of autophagy on modulating the fate of SHG-44 glioma cells.

  4. Efficient generation of lens progenitor cells from cataract patient-specific induced pluripotent stem cells.

    Directory of Open Access Journals (Sweden)

    Xiaodi Qiu

    Full Text Available The development of a technique to induce the transformation of somatic cells to a pluripotent state via the ectopic expression of defined transcription factors was a transformational event in the field of regenerative medicine. The development of this technique also impacted ophthalmology, as patient-specific induced pluripotent stemcells (iPSCs may be useful resources for some ophthalmological diseases. The lens is a key refractive element in the eye that focuses images of the visual world onto the retina. To establish a new model for drug screening to treat lens diseases and investigating lens aging and development, we examined whether human lens epithelial cells (HLECs could be induced into iPSCs and if lens-specific differentiation of these cells could be achieved under defined chemical conditions. We first efficiently reprogrammed HLECs from age-related cataract patients to iPSCs with OCT-4, SOX-2, and KLF-4. The resulting HLEC-derived iPS (HLE-iPS colonies were indistinguishable from human ES cells with respect to morphology, gene expression, pluripotent marker expression and their ability to generate all embryonic germ-cell layers. Next, we performed a 3-step induction procedure: HLE-iPS cells were differentiated into large numbers of lens progenitor-like cells with defined factors (Noggin, BMP and FGF2, and we determined that these cells expressed lens-specific markers (PAX6, SOX2, SIX3, CRYAB, CRYAA, BFSP1, and MIP. In addition, HLE-iPS-derived lens cells exhibited reduced expression of epithelial mesenchymal transition (EMT markers compared with human embryonic stem cells (hESCs and fibroblast-derived iPSCs. Our study describes a highly efficient procedure for generating lens progenitor cells from cataract patient HLEC-derived iPSCs. These patient-derived pluripotent cells provide a valuable model for studying the developmental and molecular biological mechanisms that underlie cell determination in lens development and cataract

  5. Statins induce differentiation and cell death in neurons and astroglia.

    Science.gov (United States)

    März, Pia; Otten, Uwe; Miserez, André R

    2007-01-01

    Statins are potent inhibitors of the hydroxy-methyl-glutaryl-coenzyme A reductase, the rate limiting enzyme for cholesterol biosynthesis. Experimental and clinical studies with statins suggest that they have beneficial effects on neurodegenerative disorders. Thus, it was of interest to characterize the direct effects of statins on CNS neurons and glial cells. We have treated defined cultures of neurons and astrocytes of newborn rats with two lipophilic statins, atorvastatin and simvastatin, and analyzed their effects on morphology and survival. Treatment of astrocytes with statins induced a time- and dose-dependent stellation, followed by apoptosis. Similarly, statins elicited programmed cell death of cerebellar granule neurons but with a higher sensitivity. Analysis of different signaling cascades revealed that statins fail to influence classical pathways such as Akt or MAP kinases, known to be activated in CNS cells. In addition, astrocyte stellation triggered by statins resembled dibutryl-cyclic AMP (db-cAMP) induced morphological differentiation. However, in contrast to db-cAMP, statins induced upregulation of low-density lipoprotein receptors, without affecting GFAP expression, indicating separate underlying mechanisms. Analysis of the cholesterol biosynthetic pathway revealed that lack of mevalonate and of its downstream metabolites, mainly geranylgeranyl-pyrophosphate (GGPP), is responsible for the statin-induced apoptosis of neurons and astrocytes. Moreover, astrocytic stellation triggered by statins was inhibited by mevalonate and GGPP. Interestingly, neuronal cell death was significantly reduced in astrocyte/neuron co-cultures treated with statins. We postulate that under these conditions signals provided by astrocytes, e.g., isoprenoids play a key role in neuronal survival.

  6. Vectorology and Factor Delivery in Induced Pluripotent Stem Cell Reprogramming

    OpenAIRE

    Hu, Kejin

    2014-01-01

    Induced pluripotent stem cell (iPSC) reprogramming requires sustained expression of multiple reprogramming factors for a limited period of time (10–30 days). Conventional iPSC reprogramming was achieved using lentiviral or simple retroviral vectors. Retroviral reprogramming has flaws of insertional mutagenesis, uncontrolled silencing, residual expression and re-activation of transgenes, and immunogenicity. To overcome these issues, various technologies were explored, including adenoviral vect...

  7. Reprogramming human B cells into induced pluripotent stem cells and its enhancement by C/EBPα.

    Science.gov (United States)

    Bueno, C; Sardina, J L; Di Stefano, B; Romero-Moya, D; Muñoz-López, A; Ariza, L; Chillón, M C; Balanzategui, A; Castaño, J; Herreros, A; Fraga, M F; Fernández, A; Granada, I; Quintana-Bustamante, O; Segovia, J C; Nishimura, K; Ohtaka, M; Nakanishi, M; Graf, T; Menendez, P

    2016-03-01

    B cells have been shown to be refractory to reprogramming and B-cell-derived induced pluripotent stem cells (iPSC) have only been generated from murine B cells engineered to carry doxycycline-inducible Oct4, Sox2, Klf4 and Myc (OSKM) cassette in every tissue and from EBV/SV40LT-immortalized lymphoblastoid cell lines. Here, we show for the first time that freshly isolated non-cultured human cord blood (CB)- and peripheral blood (PB)-derived CD19+CD20+ B cells can be reprogrammed to iPSCs carrying complete VDJH immunoglobulin (Ig) gene monoclonal rearrangements using non-integrative tetracistronic, but not monocistronic, OSKM-expressing Sendai Virus. Co-expression of C/EBPα with OSKM facilitates iPSC generation from both CB- and PB-derived B cells. We also demonstrate that myeloid cells are much easier to reprogram than B and T lymphocytes. Differentiation potential back into the cell type of their origin of B-cell-, T-cell-, myeloid- and fibroblast-iPSCs is not skewed, suggesting that their differentiation does not seem influenced by 'epigenetic memory'. Our data reflect the actual cell-autonomous reprogramming capacity of human primary B cells because biased reprogramming was avoided by using freshly isolated primary cells, not exposed to cytokine cocktails favoring proliferation, differentiation or survival. The ability to reprogram CB/PB-derived primary human B cells offers an unprecedented opportunity for studying developmental B lymphopoiesis and modeling B-cell malignancies.

  8. Tumor cell lysate-pulsed dendritic cells induce a T cell response against colon cancer in vitro and in vivo.

    Science.gov (United States)

    Wu, Yu-gang; Wu, Guang-zhou; Wang, Liang; Zhang, Yan-Yun; Li, Zhong; Li, De-Chun

    2010-09-01

    To investigate whether tumor cell lysate-pulsed (TP) dendritic cells (DCs) induce cytotoxic T lymphocyte (CTL) activity against colon cancer in vitro and in vivo. Hematopoietic progenitor cells were magnetically isolated from BALB/c mice bone marrow cells. These cells were cultured with cytokines GM-CSF, IL-4, and TNFalpha to induce their maturation. They were analyzed by morphological observation and phenotype analysis. DCs were pulsed with tumor cell lysate obtained by rapid freezing and thawing at a 1:3 DC:tumor cell ratio. CTL activity and interferon gamma (IFNgamma) secretion was evaluated ex vivo. In order to determine whether or not vaccination with CT26 TP DCs induce the therapeutic potential in the established colon tumor model, CT26 colon tumor cells were implanted subcutaneously (s.c.) in the midflank of naïve BALB/c mice. Tumor-bearing mice were injected with vaccination with CT26 TP DCs on days 3 and 10. Tumor growth was assessed every 2-3 days. Finally, CTL activity and IFNgamma secretion were evaluated in immunized mice. Hematopoietic progenitor cells from mice bone marrow cells cultured with cytokines for 8 days showed the character of typical mature DCs. Morphologically, these cells were large with oval or irregularly shaped nuclei and with many small dendrites. Phenotypically, FACS analysis showed that they expressed high levels of MHC II, CD11b, CD80, and CD86 antigen, and were negative for CD8alpha. However, immature DCs cultured with cytokines for 5 days did not have typical DCs phenotypic markers. Ex vivo primed T cells with CT26 TP DCs were able to induce effective CTL activity against CT26 tumor cells, but not B16 tumor cells (E:T = 100:1, 60.36 +/- 7.11% specific lysis in CT26 group vs. 17.36 +/- 4.10% specific lysis in B16 group), and produced higher levels of IFNgamma when stimulated with CT26 tumor cells but not when stimulated with B16 tumor cells (1210.33 +/- 72.15 pg/ml in CT26 group vs. 182.25 +/- 25.51 pg/ml in B16 group, P models

  9. Autophagy contributes to gefitinib-induced glioma cell growth inhibition

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Cheng-Yi [Department of Surgery, Fong-Yuan Hospital, Taichung 420, Taiwan (China); Graduate Institute of Pharmaceutical Science and Technology, Central Taiwan University of Science and Technology, Taichung 406, Taiwan (China); Kuan, Yu-Hsiang [Department of Pharmacology, School of Medicine, Chung Shan Medical University, Taichung 402, Taiwan (China); Department of Pharmacy, Chung Shan Medical University Hospital, Taichung 402, Taiwan (China); Ou, Yen-Chuan; Li, Jian-Ri [Division of Urology, Taichung Veterans General Hospital, Taichung 407, Taiwan (China); Wu, Chih-Cheng [Department of Anesthesiology, Taichung Veterans General Hospital, Taichung 407, Taiwan (China); Department of Financial and Computational Mathematics, Providence University, Taichung 433, Taiwan (China); Pan, Pin-Ho [Department of Pediatrics, Tungs’ Taichung MetroHarbor Hospital, Taichung 435, Taiwan (China); Chen, Wen-Ying [Department of Veterinary Medicine, National Chung Hsing University, Taichung 402, Taiwan (China); Huang, Hsuan-Yi [Department of Surgery, Fong-Yuan Hospital, Taichung 420, Taiwan (China); Chen, Chun-Jung, E-mail: cjchen@vghtc.gov.tw [Department of Medical Research, Taichung Veterans General Hospital, Taichung 407, Taiwan (China); Institute of Biomedical Sciences, National Chung Hsing University, Taichung 402, Taiwan (China); Rong Hsing Research Center for Translational Medicine, National Chung Hsing University, Taichung 402, Taiwan (China); Center for General Education, Tunghai University, Taichung 407, Taiwan (China); Department of Nursing, HungKuang University, Taichung 433, Taiwan (China)

    2014-09-10

    Epidermal growth factor receptor tyrosine kinase inhibitors, including gefitinib, have been evaluated in patients with malignant gliomas. However, the molecular mechanisms involved in gefitinib-mediated anticancer effects against glioma are incompletely understood. In the present study, the cytostatic potential of gefitinib was demonstrated by the inhibition of glioma cell growth, long-term clonogenic survival, and xenograft tumor growth. The cytostatic consequences were accompanied by autophagy, as evidenced by monodansylcadaverine staining of acidic vesicle formation, conversion of microtubule-associated protein-1 light chain 3-II (LC3-II), degradation of p62, punctate pattern of GFP-LC3, and conversion of GFP-LC3 to cleaved-GFP. Autophagy inhibitor 3-methyladenosine and chloroquine and genetic silencing of LC3 or Beclin 1 attenuated gefitinib-induced growth inhibition. Gefitinib-induced autophagy was not accompanied by the disruption of the Akt/mammalian target of rapamycin signaling. Instead, the activation of liver kinase-B1/AMP-activated protein kinase (AMPK) signaling correlated well with the induction of autophagy and growth inhibition caused by gefitinib. Silencing of AMPK suppressed gefitinib-induced autophagy and growth inhibition. The crucial role of AMPK activation in inducing glioma autophagy and growth inhibition was further supported by the actions of AMP mimetic AICAR. Gefitinib was shown to be capable of reducing the proliferation of glioma cells, presumably by autophagic mechanisms involving AMPK activation. - Highlights: • Gefitinib causes cytotoxic and cytostatic effect on glioma. • Gefitinib induces autophagy. • Gefitinib causes cytostatic effect through autophagy. • Gefitinib induces autophagy involving AMPK.

  10. Demethoxycurcumin Retards Cell Growth and Induces Apoptosis in Human Brain Malignant Glioma GBM 8401 Cells

    Directory of Open Access Journals (Sweden)

    Tzuu-Yuan Huang

    2012-01-01

    Full Text Available Demethoxycurcumin (DMC; a curcumin-related demethoxy compound has been recently shown to display antioxidant and antitumor activities. It has also produced a potent chemopreventive action against cancer. In the present study, the antiproliferation (using the MTT assay, DMC was found to have cytotoxic activities against GBM 8401 cell with IC50 values at 22.71 μM and induced apoptosis effects of DMC have been investigated in human brain malignant glioma GBM 8401 cells. We have studied the mitochondrial membrane potential (MMP, DNA fragmentation, caspase activation, and NF-κB transcriptional factor activity. By these approaches, our results indicated that DMC has produced an inhibition of cell proliferation as well as the activation of apoptosis in GBM 8401 cells. Both effects were observed to increase in proportion with the dosage of DMC treatment, and the apoptosis was induced by DMC in human brain malignant glioma GBM 8401 cells via mitochondria- and caspase-dependent pathways.

  11. Generation of induced pluripotent stem cells with high efficiency from human umbilical cord blood mononuclear cells.

    Science.gov (United States)

    Wang, Juan; Gu, Qi; Hao, Jie; Bai, Donghui; Liu, Lei; Zhao, Xiaoyang; Liu, Zhonghua; Wang, Liu; Zhou, Qi

    2013-10-01

    Human induced pluripotent stem cells (iPSCs) hold great promise for regenerative medicine. Generating iPSCs from immunologically immature newborn umbilical cord blood mononuclear cells (UCBMCs) is of great significance. Here we report generation of human iPSCs with great efficiency from UCBMCs using a dox-inducible lentiviral system carrying four Yamanaka factors. We generated these cells by optimizing the existing iPSC induction protocol. The UCBMC-derived iPSCs (UCB-iPSCs) have characteristics that are identical to pluripotent human embryonic stem cells (hESCs). This study highlights the use of UCBMCs to generate highly functional human iPSCs that could accelerate the development of cell-based regenerative therapy for patients suffering from various diseases.

  12. Cell wall dynamics modulate acetic acid-induced apoptotic cell death of Saccharomyces cerevisiae

    Directory of Open Access Journals (Sweden)

    António Rego

    2014-08-01

    Full Text Available Acetic acid triggers apoptotic cell death in Saccharomyces cerevisiae, similar to mammalian apoptosis. To uncover novel regulators of this process, we analyzed whether impairing MAPK signaling affected acetic acid-induced apoptosis and found the mating-pheromone response and, especially, the cell wall integrity pathways were the major mediators, especially the latter, which we characterized further. Screening downstream effectors of this pathway, namely targets of the transcription factor Rlm1p, highlighted decreased cell wall remodeling as particularly important for acetic acid resistance. Modulation of cell surface dynamics therefore emerges as a powerful strategy to increase acetic acid resistance, with potential application in industrial fermentations using yeast, and in biomedicine to exploit the higher sensitivity of colorectal carcinoma cells to apoptosis induced by acetate produced by intestinal propionibacteria.

  13. Fullerene derivatives protect endothelial cells against NO-induced damage

    Energy Technology Data Exchange (ETDEWEB)

    Lao Fang; Han Dong; Qu Ying; Liu Ying; Zhao Yuliang; Chen Chunying [CAS Key Laboratory for Biological Effects of Nanomaterials and Nanosafety, National Center for Nanoscience and Technology (NCNST), Beijing 100190 (China); Li Wei [CAS Key Laboratory for Nuclear Analytical Techniques, Institute of High Energy Physics (IHEP), Chinese Academy of Sciences, Beijing 100049 (China)], E-mail: chenchy@nanoctr.cn

    2009-06-03

    Functional fullerene derivatives have been demonstrated with potent antioxidation properties. Nitric oxide (NO) is a free radical that plays a part in leading to brain damage when it is accumulated to a high concentration. The possible scavenging activity of NO by the hydroxylated fullerene derivative C{sub 60}(OH){sub 22} and malonic acid derivative C{sub 60}(C(COOH){sub 2}){sub 2} was investigated using primary rat brain cerebral microvessel endothelial cells (CMECs). Results demonstrate that sodium nitroprusside (SNP), used as an NO donor, caused a marked decrease in cell viability and an increase in apoptosis. However, fullerene derivatives can remarkably protect against the apoptosis induced by NO assault. In addition, fullerene derivatives can also prevent NO-induced depolymerization of cytoskeleton and damage of the nucleus and accelerate endothelial cell repair. Further investigation shows that the sudden increase of the intercellular reactive oxygen species (ROS) induced by NO was significantly attenuated by post-treatment with fullerene derivatives. Our results suggest that functional fullerene derivatives are potential applications for NO-related disorders.

  14. Hyperinsulinism induced by targeted suppression of beta cell KATP channels.

    Science.gov (United States)

    Koster, J C; Remedi, M S; Flagg, T P; Johnson, J D; Markova, K P; Marshall, B A; Nichols, C G

    2002-12-24

    ATP-sensitive K+ (K(ATP)) channels couple cell metabolism to electrical activity. To probe the role of K(ATP) in glucose-induced insulin secretion, we have generated transgenic mice expressing a dominant-negative, GFP-tagged K(ATP) channel subunit in which residues 132-134 (Gly-Tyr-Gly) in the selectivity filter were replaced by Ala-Ala-Ala, under control of the insulin promoter. Transgene expression was confirmed by both beta cell-specific green fluorescence and complete suppression of channel activity in those cells ( approximately 70%) that did fluoresce. Transgenic mice developed normally with no increased mortality and displayed normal body weight, blood glucose levels, and islet architecture. However, hyperinsulinism was evident in adult mice as (i) a disproportionately high level of circulating serum insulin for a given glucose concentration ( approximately 2-fold increase in blood insulin), (ii) enhanced glucose-induced insulin release from isolated islets, and (iii) mild yet significant enhancement in glucose tolerance. Enhanced glucose-induced insulin secretion results from both increased glucose sensitivity and increased release at saturating glucose concentration. The results suggest that incomplete suppression of K(ATP) channel activity can give rise to a maintained hyperinsulinism.

  15. Para-toluenesulfonamide induces tongue squamous cell carcinoma cell death through disturbing lysosomal stability.

    Science.gov (United States)

    Liu, Zhe; Liang, Chenyuan; Zhang, Zhuoyuan; Pan, Jian; Xia, Hui; Zhong, Nanshan; Li, Longjiang

    2015-11-01

    Para-toluenesulfonamide (PTS) has been implicated with anticancer effects against a variety of tumors. In the present study, we investigated the inhibitory effects of PTS on tongue squamous cell carcinoma (Tca-8113) and explored the lysosomal and mitochondrial changes after PTS treatment in vitro. High-performance liquid chromatography showed that PTS selectively accumulated in Tca-8113 cells with a relatively low concentration in normal fibroblasts. Next, the effects of PTS on cell viability, invasion, and cell death were determined. PTS significantly inhibited Tca-8113 cells' viability and invasive ability with increased cancer cell death. Flow cytometric analysis and the lactate dehydrogenase release assay showed that PTS induced cancer cell death by activating apoptosis and necrosis simultaneously. Morphological changes, such as cellular shrinkage, nuclear condensation as well as formation of apoptotic body and secondary lysosomes, were observed, indicating that PTS might induce cell death through disturbing lysosomal stability. Lysosomal integrity assay and western blot showed that PTS increased lysosomal membrane permeabilization associated with activation of lysosomal cathepsin B. Finally, PTS was shown to inhibit ATP biosynthesis and induce the release of mitochondrial cytochrome c. Therefore, our findings provide a novel insight into the use of PTS in cancer therapy.

  16. Antibiotic drug tigecycline inhibited cell proliferation and induced autophagy in gastric cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Chunling; Yang, Liqun; Jiang, Xiaolan [State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing 400716 (China); Xu, Chuan [Division of Scientific Research and Training, General Hospital of PLA Chengdu Military Area Command, Chengdu, Sichuan 610083 (China); Wang, Mei; Wang, Qinrui [State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing 400716 (China); Zhou, Zhansong, E-mail: zhouzhans@sina.com [Institute of Urinary Surgery, Southwest Hospital, Third Military Medical University, Chongqing 400038 (China); Xiang, Zhonghuai [State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing 400716 (China); Cui, Hongjuan, E-mail: hcui@swu.edu.cn [State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing 400716 (China)

    2014-03-28

    Highlights: • Tigecycline inhibited cell growth and proliferation in human gastric cancer cells. • Tigecycline induced autophagy not apoptosis in human gastric cancer cells. • AMPK/mTOR/p70S6K pathway was activated after tigecycline treatment. • Tigecycline inhibited tumor growth in xenograft model of human gastric cancer cells. - Abstract: Tigecycline acts as a glycylcycline class bacteriostatic agent, and actively resists a series of bacteria, specifically drug fast bacteria. However, accumulating evidence showed that tetracycline and their derivatives such as doxycycline and minocycline have anti-cancer properties, which are out of their broader antimicrobial activity. We found that tigecycline dramatically inhibited gastric cancer cell proliferation and provided an evidence that tigecycline induced autophagy but not apoptosis in human gastric cancer cells. Further experiments demonstrated that AMPK pathway was activated accompanied with the suppression of its downstream targets including mTOR and p70S6K, and ultimately induced cell autophagy and inhibited cell growth. So our data suggested that tigecycline might act as a candidate agent for pre-clinical evaluation in treatment of patients suffering from gastric cancer.

  17. Vitamin E Modulates Cigarette Smoke Extract-induced Cell Apoptosis in Mouse Embryonic Cells

    Directory of Open Access Journals (Sweden)

    Zhao-Li Chen, Jian Tao, Jie Yang, Zhen-Li Yuan, Xing-Hua Liu, Min Jin, Zhi-Qiang Shen, Lu Wang, Hai-Feng Li, Zhi-Gang Qiu, Jing-Feng Wang, Xin-Wei Wang, Jun-Wen Li

    2011-01-01

    Full Text Available Vitamin E (VE can effectively prevent occurrence of lung cancer caused by passive smoking in mice. However, whether VE prevents smoking-induced cytotoxicity remains unclear. In this study, a primary culture of embryonic lung cells (ELCs was used to observe the cytotoxic effects of cigarette smoke extract (CSE, including its influence on cell survival, cell cycle, apoptosis, and DNA damage, and also to examine the effects of VE intervention on CSE-induced cytotoxicity. Our results showed that CSE could significantly inhibit the survival of ELCs with dose- and time-dependent effects. Furthermore, CSE clearly disturbed the cell cycle of ELCs by decreasing the proportion of cells at the S and G2/M phases and increasing the proportion of cells at the G0/G1 phase. CSE promoted cell apoptosis, with the highest apoptosis rate reaching more than 40%. CSE also significantly caused DNA damage of ELCs. VE supplementation could evidently inhibit or reverse the cytotoxic effects of CSE in a dose- and time-dependent manner. The mechanism of CSE effects on ELCs and that of VE intervention might involve the mitochondrial pathway of cytochrome c-mediated caspase activation. Our study validate that VE plays a clearly protective effect against CSE-induced cytotoxicity in mouse embryonic lung cells.

  18. Autophagy Accompanied with Bisdemethoxycurcumin-induced Apoptosis in Non-small Cell Lung Cancer Cells

    Institute of Scientific and Technical Information of China (English)

    XU Jin Hong; YANG He Ping; ZHOU Xiang Dong; WANG Hai Jing; GONG Liang; TANG Chun Lan

    2015-01-01

    Objective To investigate the effects of bisdemethoxycurcumin (BDMC) on non-small cell lung cancer (NSCLC) cell line, A549, and the highly metastatic lung cancer 95D cells. Methods CCK-8 assay was used to assess the effect of BDMC on cytotoxicity. Flow cytometry was used to evaluate apoptosis. Western blot analysis, electron microscopy, and quantification of GFP-LC3 punctuates were used to test the effect of BDMC on autophagy and apoptosis of lung cancer cells. Results BDMC inhibited the viability of NSCLC cells, but had no cytotoxic effects on lung small airway epithelial cells (SAECs). The apoptotic cell death induced by BDMC was accompanied with the induction of autophagy in NSCLC cells. Blockage of autophagy by the autophagy inhibitor 3-methyladenine (3-MA) repressed the growth inhibitory effects and induction of apoptosis by BDMC. In addition, BDMC treatment significantly decreased smoothened (SMO) and the transcription factor glioma-associated oncogene 1 (Gli1) expression. Furthermore, depletion of Gli1 by siRNA and cyclopamine (a specific SMO inhibitor) induced autophagy. Conclusion Aberrant activation of Hedgehog (Hh) signaling has been implicated in several human cancers, including lung cancers. The present findings provide direct evidence that BDMC-induced autophagy plays a pro-death role in NSCLC, in part, by inhibiting Hedgehog signaling.

  19. Mast Cell Proteases 6 and 7 Stimulate Angiogenesis by Inducing Endothelial Cells to Release Angiogenic Factors.

    Directory of Open Access Journals (Sweden)

    Devandir Antonio de Souza Junior

    Full Text Available Mast cell proteases are thought to be involved with tumor progression and neo-vascularization. However, their exact role is still unclear. The present study was undertaken to further elucidate the function of specific subtypes of recombinant mouse mast cell proteases (rmMCP-6 and 7 in neo-vascularization. SVEC4-10 cells were cultured on Geltrex® with either rmMCP-6 or 7 and tube formation was analyzed by fluorescence microscopy and scanning electron microscopy. Additionally, the capacity of these proteases to induce the release of angiogenic factors and pro and anti-angiogenic proteins was analyzed. Both rmMCP-6 and 7 were able to stimulate tube formation. Scanning electron microscopy showed that incubation with the proteases induced SVEC4-10 cells to invade the gel matrix. However, the expression and activity of metalloproteases were not altered by incubation with the mast cell proteases. Furthermore, rmMCP-6 and rmMCP-7 were able to induce the differential release of angiogenic factors from the SVEC4-10 cells. rmMCP-7 was more efficient in stimulating tube formation and release of angiogenic factors than rmMCP-6. These results suggest that the subtypes of proteases released by mast cells may influence endothelial cells during in vivo neo-vascularization.

  20. Area Expansivity Moduli of Regenerating Plant Protoplast Cell Walls Exposed to Shear Flows

    Science.gov (United States)

    Fujimura, Yuu; Iino, Masaaki; Watanabe, Ugai

    2005-05-01

    To control the elasticity of the plant cell wall, protoplasts isolated from cultured Catharanthus roseus cells were regenerated in shear flows of 115 s-1 (high shear) and 19.2 s-1 (low shear, as a control). The surface area expansivity modulus and the surface breaking strength of these regenerating protoplasts were measured by a micropipette aspiration technique. Cell wall synthesis was also measured using a cell wall-specific fluorescent dye. High shear exposure for 3 h doubled both the surface area modulus and breaking strength observed under low shear, significantly decreased cell wall synthesis, and roughly quadrupled the moduli of the cell wall. Based on the cell wall synthesis data, we estimated the three-dimensional modulus of the cell wall to be 4.1± 1.2 GPa for the high shear, and 0.35± 0.2 GPa for the low shear condition, using the surface area expansivity modulus divided by the cell wall thickness, which is identical with the Young’s modulus divided by 2(1-σ), where σ is Poisson's ratio. We concluded that high shear exposure considerably strengthens the newly synthesized cell wall.

  1. Shear induced diffusion in a red blood cell suspension

    Science.gov (United States)

    Podgorski, Thomas; Grandchamp, Xavier; Srivastav, Aparna; Coupier, Gwennou

    2012-11-01

    In the microcirculation, blood exhibits an inhomogeneous structure which results in the well know Fahraeus-Lindqvist effect : the apparent viscosity decreases when the diameter of the capillary decreases due to the formation of a marginal cell depletion layer (known as plasma skimming). This structure is a consequence of several phenomena, which include i) the migration of cells aways from walls due to lift forces and gradients of shear and ii) shear induced diffusion due to collisions and interactions among cells. We investigated these phenomena through experiments in simple shear and microchannel flows, with dilute suspensions of vesicles and blood cells. Pairwise interactions between suspended objects result in non-linear and flow-dependent diffusion, whose properties have been measured in different experiments for vesicles and blood cells. The injection of a sheet of concentrated blood cell suspension in a microchannel with a rectangular cross-section allows, through the measurement of its widening along the channel, to measure the diffusivity of blood cells, both in the local plane of shear and in the vorticity direction.

  2. Zoledronic acid induces apoptosis and autophagy in cervical cancer cells.

    Science.gov (United States)

    Wang, I-Te; Chou, Shou-Chu; Lin, Ying-Chin

    2014-12-01

    Cervical cancer is one of the most common gynecological cancers in association with high mortality and morbidity. The present study was aimed to investigate the in vitro effects of zoledronic acid (ZA) on viability and induction of apoptosis and autophagy as well as inflammatory effects in three human cervical cancer cell lines (HeLa, SiHa, and CaSki). Cell viability was measured by 3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide (MTT) assay. Induction of apoptosis was determined by quantitation of expression level of B cell lymphoma 2 (Bcl-2) and Bax messenger RNA (mRNA) and identification of the proteolytic cleavage of poly (ADP)-ribose polymerase (PARP) and caspase-3. Autophagic effects were examined by quantitation of mRNA expression of autophagy protein 5 (ATG5) and beclin1 and identifying accumulation of microtubule-associated protein 1 light chain 3 (LC3)-II. Inflammatory effect was determined by measuring expression and production of IL-6 and cyclooxygenase-2 (Cox-2). The results showed ZA significantly inhibited cell viability of cervical cancer cells. ZA-induced cell death displayed features characteristic to both apoptosis and autophagy and was associated with different changes in the levels of Bcl-2 and Bax in the various cervical cancer lines. Expression of metastatic cytokines, IL-6 and Cox-2, was upregulated in the presence of ZA at low concentration. Our data revealed that ZA inhibits cervical cancer cells through the synergistic effect of apoptosis induction and autophagy activation.

  3. Induced pluripotent stem cells and their implication for regenerative medicine.

    Science.gov (United States)

    Csobonyeiova, Maria; Polak, Stefan; Koller, Jan; Danisovic, Lubos

    2015-06-01

    In 2006 Yamanaka's group showed that stem cells with properties similar to embryonic stem cells could be generated from mouse fibroblasts by introducing four genes. These cells were termed induced pluripotent stem cells (iPSCs). Because iPSCs avoid many of ethical concerns associated with the use of embryonic material, they have great potential in cell-based regenerative medicine. They are suitable also for other various purposes, including disease modelling, personalized cell therapy, drug or toxicity screening and basic research. Moreover, in the future, there might become possible to generate organs for human transplantation. Despite these progresses, several studies have raised the concern for genetic and epigenetic abnormalities of iPSCs that could contribute to immunogenicity of some cells differentiated from iPSCs. Recent methodological improvements are increasing the ease and efficacy of reprogramming, and reducing the genomic modification. However, to minimize or eliminate genetic alternations in the derived iPSC line creation, factor-free human iPSCs are necessary. In this review we discuss recent possibilities of using iPSCs for clinical applications and new advances in field of their reprogramming methods. The main goal of present article was to review the current knowledge about iPSCs and to discuss their potential for regenerative medicine.

  4. DJ-1 mediates paraquat-induced dopaminergic neuronal cell death.

    Science.gov (United States)

    Kwon, Hyun Joo; Heo, Jun Young; Shim, Jung Hee; Park, Ji Hoon; Seo, Kang Sik; Ryu, Min Jeong; Han, Jeong Su; Shong, Minho; Son, Jin H; Kweon, Gi Ryang

    2011-04-25

    There are two causes of Parkinson's disease (PD): environmental insults and genetic mutations of PD-associated genes. Environmental insults and genetic mutations lead to mitochondrial dysfunction, and a combination of mitochondrial dysfunction and increased oxidative stress in dopaminergic neurons is thought to contribute to the pathogenesis of PD. Among the PD-associated genes, DJ-1 acts as a redox sensor for oxidative stress and has been also proposed to maintain mitochondrial complex I activity. To understand molecular functions of DJ-1 in the cell, we have generated DJ-1 null cells from the DJ-1(-/-) mouse embryos. Using these null cells, we investigated the susceptibility to an environmental toxin, paraquat, which is known to inhibit mitochondrial complex I. Interestingly, we found that DJ-1 null cells showed a resistance to paraquat-induced apoptosis, including reduced poly (ADP-ribose) polymerase and procaspase-3. Also DJ-1 null cells generated less superoxide than SN4741 cells by paraquat treatment. Consistent with the reduced paraquat sensitivity, DJ-1 null cells showed reduced complex I activity, which was partially rescued by ectopic DJ-I expression. In summary, our results suggest that DJ-1 is critical to maintain mitochondrial complex I and complex I could be a key target in interaction of paraquat toxicity and DJ-1 for giving rise to PD.

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

    Science.gov (United States)

    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.

  6. Simple and sensitive method for monitoring drug-induced cell injury in cultured cells

    Energy Technology Data Exchange (ETDEWEB)

    Shirhatti, V.; Krishna, G.

    1985-06-01

    A simple, sensitive method has been developed for evaluating cell injury noninvasively in monolayer cells in culture. The cell ATP pool was radiolabeled by incubating the cells with (/sup 14/C)adenine. The uptake and incorporation of (/sup 14/C)adenine was shown to proportional to the number of cells. As determined by HPLC, about 65-70% of the incorporated /sup 14/C label was in the ATP pool, 15-20% was in the ADP pool, and the rest was in the 5'-AMP pool. When prelabeled cells were exposed to toxic drugs (acetaminophen, calcium ionophore A-23187, or daunomycin) there was a marked decrease in cell ATP with a concomitant increase in leakage of labeled nucleotides, mainly 5'-AMP and 5'IMP. The authors have shown that leakage of /sup 14/C label into the medium from the prelabeled cells may be employed for quantitation of cell injury. This new measure of toxicity was shown to correlate very well with LDH leakage from the cells, which is a well accepted measure of cell injury. The leakage of 5'-(/sup 14/C)AMP also correlated very well with the reduction of cell ATP in cardiac myocytes. This method has been used for monitoring drug-induced toxicity in liver cells, cardiac myocytes, and LB cells.

  7. Resveratrol Induces Apoptosis in Human Osteosarcoma MG63 Cells

    Institute of Scientific and Technical Information of China (English)

    Yan Liu; Xin Wang; Yuxin Xie; Jingui Zhang; Qingshan Wang; Xianhui Xu

    2008-01-01

    OBJECTIVE To investigate apoptosis in human osteosarcoma MG63 cells induced by resveratrol and the molecular mechanism involved.METHODS MG63 cells were treated with different concentrations of resveratrol and transmission electron microscopy was used to observe morphological changes occurring in apoptosis.The MTT method was used to determine the inhibitory rate and flow cytometry was used to assess apoptosis and to analyze the expression of the p21ciP1/WAF1 and survivin proteins;the expression of p21ciP1/WAF1 and survivin mRNAs was analyzed by the reverse transcriptase polymerase chain reaction (RT-PCR).RESULTS After resveratrol treatment,the growth of the MG63 cells was significantly inhibited in a time- and dose-dependent fashion.By transmission electron microscopy,the cells displayed morphological changes characteristic of apoptosis,including formation of cytoplasmic vacuoles,chromatin condensation and margination.Flow cytometry showed that the growth of the cells was inhibited after resveratrol (10 mg/L and 20 mg/L) treatment.The inhibitory rates were (11.9 ±0.63)% and (19.7 ± 0.88)%respectively.The quantity of treated cells in G0/G1 transition was increased,but the number in the S phase and G2/M transition was decreased.A subdiploid peak was observed.The expression of p21ciP1/WAF1 was up-regulated while survivin was down-regulated.CONCLUSION Resveratrol can inhibit growth and induce apoptosis of MG63 cells.Its molecular mechanism might be related to modulation of survivin and p21ciP1/WAF1 expression.

  8. Induction of human embryonic and induced pluripotent stem cells into urothelium.

    Science.gov (United States)

    Osborn, Stephanie L; Thangappan, Ravikumar; Luria, Ayala; Lee, Justin H; Nolta, Jan; Kurzrock, Eric A

    2014-05-01

    In vitro generation of human urothelium from stem cells would be a major advancement in the regenerative medicine field, providing alternate nonurologic and/or nonautologous tissue sources for bladder grafts. Such a model would also help decipher the mechanisms of urothelial differentiation and would facilitate investigation of deviated differentiation of normal progenitors into urothelial cancer stem cells, perhaps elucidating areas of intervention for improved treatments. Thus far, in vitro derivation of urothelium from human embryonic stem cells (hESCs) or human induced pluripotent stem (hiPS) cells has not been reported. The goal of this work was to develop an efficient in vitro protocol for the induction of hESCs into urothelium through an intermediary definitive endoderm step and free of matrices and cell contact. During directed differentiation in a urothelial-specific medium ("Uromedium"), hESCs produced up to 60% urothelium, as determined by uroplakin expression; subsequent propagation selected for 90% urothelium. Alteration of the epithelial and mesenchymal cell signaling contribution through noncell contact coculture or conditioned media did not enhance the production of urothelium. Temporospatial evaluation of transcription factors known to be involved in urothelial specification showed association of IRF1, GET1, and GATA4 with uroplakin expression. Additional hESC and hiPS cell lines could also be induced into urothelium using this in vitro system. These results demonstrate that derivation and propagation of urothelium from hESCs and hiPS cells can be efficiently accomplished in vitro in the absence of matrices, cell contact, or adult cell signaling and that the induction process appears to mimic normal differentiation.

  9. Galectin-3 induces pulmonary artery endothelial cell morphogenesis and angiogenesis

    Institute of Scientific and Technical Information of China (English)

    ZHANG Li; LI Yu-mei; WANG Xiao-yan; ZHU Da-ling

    2016-01-01

    AIM:Increasing evidence suggests that carbohydrate-binding proteins play an essential role in tumor growth and metastasis .Ga-lectin-3, a multifunctional protein of an expanding family of β-galactoside-binding animal lectins , is the major nonintegrin cellular laminin-binding protein , and is implicated in a variety of biologic events , such as inflammation and angiogenesis .Because galectin-3 expression was shown to participate in mediating tumor angiogenesis and initiate signaling cascades in several diseases .We hypothe-sized that galectin-3 may promote pulmonary vascular endothelial neovascularization .METHODS:Hypoxic and MCT rat model of pul-monary artery remodeling was used .The mRNA and protein levels of galectin-3 in rats were measured by in situ hybrization and West-ern blot analysis.Endothelial cell (EC) proliferation, migration and tube formation were measured using MTT , cell scratch and Matri-gel assays, respectively.Protein expression was quantitated by Western blot analysis .LC 3A/B staining was detected with cellular im-munofluorescence staining .RESULTS:We found that galectin-3 was localized on the intima and adventitial wall .Galectin-3 was in-creased after rat hypoxia and MCT administration .Galectin-3 promoted EC proliferation , migration and tube formation , while its roles were reversed by RNA interference.Galectin-3 induced Atg 5, Beclin-1, LAMP-2, and LC 3A/B expression increases.Galectin-3 al-so increased LC 3A/B staining in ECs.Akt/mTOR and GSK-3βsignaling pathways were activated after galectin-3 treated ECs using its specific phosphorylation antibodies , while blocked it with LY294002 inhibited cell autophagy and EC dynamic alterations induced by galectin-3.CONCLUSION:These findings demonstrate that galectin-3 can induce an Akt signaling cascade leading to cell autoph-agy, and then the differentiation and angiogenesis of pulmonary artery endothelial cells .

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

    LENUS (Irish Health Repository)

    O'Sullivan-Coyne, G

    2009-10-06

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

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

    LENUS (Irish Health Repository)

    O'Sullivan-Coyne, G

    2012-01-31

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

  12. Immunological considerations for embryonic and induced pluripotent stem cell banking.

    Science.gov (United States)

    Taylor, Craig J; Bolton, Eleanor M; Bradley, J Andrew

    2011-08-12

    Recent advances in stem cell technology have generated enthusiasm for their potential to study and treat a diverse range of human disease. Pluripotent human stem cells for therapeutic use may, in principle, be obtained from two sources: embryonic stem cells (hESCs), which are capable of extensive self-renewal and expansion and have the potential to differentiate into any somatic tissue, and induced pluripotent stem cells (iPSCs), which are derived from differentiated tissue such as adult skin fibroblasts and appear to have the same properties and potential, but their generation is not dependent upon a source of embryos. The likelihood that clinical transplantation of hESC- or iPSC-derived tissues from an unrelated (allogeneic) donor that express foreign human leucocyte antigens (HLA) may undergo immunological rejection requires the formulation of strategies to attenuate the host immune response to transplanted tissue. In clinical practice, individualized iPSC tissue derived from the intended recipient offers the possibility of personalized stem cell therapy in which graft rejection would not occur, but the logistics of achieving this on a large scale are problematic owing to relatively inefficient reprogramming techniques and high costs. The creation of stem cell banks comprising HLA-typed hESCs and iPSCs is a strategy that is proposed to overcome the immunological barrier by providing HLA-matched (histocompatible) tissue for the target population. Estimates have shown that a stem cell bank containing around 10 highly selected cell lines with conserved homozygous HLA haplotypes would provide matched tissue for the majority of the UK population. These simulations have practical, financial, political and ethical implications for the establishment and design of stem cell banks incorporating cell lines with HLA types that are compatible with different ethnic populations throughout the world.

  13. Development of an Evaluation Methodology for Loss of Large Area induced from extreme events

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sok Chul; Park, Jong Seuk; Kim, Byung Soon; Jang, Dong Ju; Lee, Seung Woo [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    USNRC announced several regulatory requirements and guidance documents regarding the event of loss of large area including 10CFR 50.54(hh), Regulatory Guide 1.214 and SRP 19.4. In Korea, consideration of loss of large area has been limitedly taken into account for newly constructing NPPs as voluntary based. In general, it is hardly possible to find available information on methodology and key assumptions for the assessment of LOLA due to 'need to know based approach'. Urgent needs exists for developing country specific regulatory requirements, guidance and evaluation methodology by themselves with the consideration of their own geographical and nuclear safety and security environments. Currently, Korea Hydro and Nuclear Power Company (KHNP) has developed an Extended Damage Mitigation Guideline (EDMG) for APR1400 under contract with foreign consulting company. The submittal guidance NEI 06-12 related to B.5.b Phase 2 and 3 focused on unit-wise mitigation strategy instead of site level mitigation or response strategy. Phase 1 mitigating strategy and guideline for LOLA (Loss of Large Area) provides emphasis on site level arrangement including cooperative networking outside organizations and agile command and control system. Korea Institute of Nuclear Safety has carried out a pilot in-house research project to develop the methodology and guideline for evaluation of LOLA since 2014. This paper introduces the summary of major results and outcomes of the aforementioned research project. After Fukushima Dai-Ichi accident, the awareness on countering the event of loss of large area induced from extreme man-made hazards or extreme beyond design basis external event. Urgent need exists to develop regulatory guidance for coping with this undesirable situation, which has been out of consideration at existing nuclear safety regulatory framework due to the expectation of rare possibility of occurrence.

  14. Construction of Larger Area Density-Uniform Plasma with Collisional Inductively Coupled Plasma Cells

    Institute of Scientific and Technical Information of China (English)

    OUYANG Liang; LIU Wandong; BAI Xiaoyan; CHEN Zhipeng; WANG Huihui; LI LUO Chen; JI Liangliang; HU Bei

    2007-01-01

    The plasma density and electron temperature of a multi-source plasma system composed of several collisional inductively coupled plasma (ICP) cells were measured by a double-probe. The discharges of the ICP cells were shown to be independent of each other. Furthermore, the total plasma density at simultaneous multi-cell discharge was observed to be approximately equal to the summation of the plasma density when the cells discharge separately. Based on the linear summation phenomenon, it was shown that a larger area plasma with a uniform density and temperature profile could be constructed with multi-collisional ICP cells.

  15. AM-1 short circuit currents in small area PIN a-SiH(x) solar cells

    Science.gov (United States)

    Weinberger, B. R.; Deckman, H. W.; Wronski, C. R.; Witzke, H.

    The potential pitfalls which may lead to an overestimation of AM-1 short-circuit current densities have been investigated for 0.02 sq cm a-SiH(x) solar cell structures. The investigators have spatially profiled carrier collection in a-Si PIN solar cells, using a scanned 10 micron diameter laser beam. The small beam size yields not only microscopic information about carrier collection efficiency spectra, but permits study of carrier collection at high light intensity without significantly heating the cell. Laser scans at low illumination levels were employed to determine the true active area of PIN solar cells, and these are compared to cell collection efficiency spectra.

  16. Hypermutator Salmonella Heidelberg induces an early cell death in epithelial cells.

    Science.gov (United States)

    Le Gall-David, Sandrine; Zenbaa, Neila; Bouchard, Damien; Lavault, Marie-Thérèse; Bonnaure-Mallet, Martine; Jolivet-Gougeon, Anne; Bousarghin, Latifa

    2015-10-22

    We have previously described that a strain of Salmonella Heidelberg with a hypermutator phenotype, B182, adhered strongly to HeLa cells. In this work, we showed that this hypermutator Salmonella strain invaded HeLa epithelial cells and induced cytoskeleton alteration. Those changes lead to HeLa cell death which was characteristic of apoptosis. For the first time, we showed that this hypermutator strain induced apoptosis associated with the activation of caspases 2, 9 and 3. Complementation of B182 strain showed a decrease in cells death induction. In the presence of other Salmonella Heidelberg with a normomutator phenotype, such as WT and SL486, cell death and caspase 3 were undetectable. These results suggested that early apoptosis and caspase 3 activation were specific to B182. Besides, B182 induced LDH release and caspase 3 activation in CaCo-2 and HCT116 cells. Heat-treated B182 and diffusible products failed to induce this phenotype. Epithelial cells treatment with cytochalasin D caused the inhibition of B182 internalisation and caspase 3 activation. These results showed that this cell death required active S. Heidelberg B182 protein synthesis and bacterial internalisation. However sipB and sopB, usually involved in apoptosis induced by Salmonella were not overexpressed in B182, contrary to fimA and fliC. Comparative genome analysis showed numerous mutations as in rpoS which would be more investigated. The role of the hypermutator phenotype might be suspected to be implicated in these specific features. This result expands our knowledge about strong mutators frequently found in bacterial organisms isolated from clinical specimens.

  17. Trypsin-induced proteome alteration during cell subculture in mammalian cells

    Directory of Open Access Journals (Sweden)

    Lin Cheng-Wen

    2010-05-01

    Full Text Available Abstract Background It is essential to subculture the cells once cultured cells reach confluence. For this, trypsin is frequently applied to dissociate adhesive cells from the substratum. However, due to the proteolytic activity of trypsin, cell surface proteins are often cleaved, which leads to dysregulation of the cell functions. Methods In this study, a triplicate 2D-DIGE strategy has been performed to monitor trypsin-induced proteome alterations. The differentially expressed spots were identified by MALDI-TOF MS and validated by immunoblotting. Results 36 proteins are found to be differentially expressed in cells treated with trypsin, and proteins that are known to regulate cell metabolism, growth regulation, mitochondrial electron transportation and cell adhesion are down-regulated and proteins that regulate cell apoptosis are up-regulated after trypsin treatment. Further study shows that bcl-2 is down-regulated, p53 and p21 are both up-regulated after trypsinization. Conclusions In summary, this is the first report that uses the proteomic approach to thoroughly study trypsin-induced cell physiological changes and provides researchers in carrying out their experimental design.

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

    Directory of Open Access Journals (Sweden)

    Venus Haghshenas

    2014-10-01

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

  19. Calprotectin induces cell death in human prostate cancer cell (LNCaP) through survivin protein alteration.

    Science.gov (United States)

    Sattari, Mina; Pazhang, Yaghub; Imani, Mehdi

    2014-11-01

    Calprotectin (CP), an abundant heterodimeric cytosolic protein of neutrophils, conveys a variety of functions such as tumor cell growth arrest and antimicrobial activity. We investigated CP activity and its possible apoptosis-inducing mechanism of action against an antiandrogen therapy-resistance prostate cancer cell line LNCaP. Cell viability and Annexin V FITC assays were performed in order to investigate its cell death activity and apoptosis, respectively. In order to address cell death inducing mechanism(s), immunocytochemistry and immunobloting analysis, reactive oxygen species (ROS) and nitric oxide (NO) measurements were performed. The effective concentration of CP against LNCaP promoting LNCaP cell death was 200 µg/mL. ROS and NO levels of cells remarkably were enhanced following treatment with 50 and 100 µg/mL of CP, respectively. Protein expression of anti-apoptotic protein survivin was significantly decreased after administration of tumor cells with CP. Our data indicate that CP regulates the LNCaP cells viability via survivin-mediated pathway and ROS and NO enhancement. Thus, inhibition of survivin expression, enhancement of ROS and NO level by CP or other similar pharmaceutical agents might be effective in lowering the malignant proliferation of human prostate cancer cells.

  20. Induced pluripotent stem cell-derived neural stem cell therapies for spinal cord injury

    Institute of Scientific and Technical Information of China (English)

    Corinne A Lee-Kubli; Paul Lu

    2015-01-01

    The greatest challenge to successful treatment of spinal cord injury is the limited regenerative capacity of the central nervous system and its inability to replace lost neurons and severed axons following injury. Neural stem cell grafts derived from fetal central nervous system tissue or embryonic stem cells have shown therapeutic promise by differentiation into neurons and glia that have the potential to form functional neuronal relays across injured spinal cord segments. However, implementation of fetal-derived or embryonic stem cell-derived neural stem cell ther-apies for patients with spinal cord injury raises ethical concerns. Induced pluripotent stem cells can be generated from adult somatic cells and differentiated into neural stem cells suitable for therapeutic use, thereby providing an ethical source of implantable cells that can be made in an autologous fashion to avoid problems of immune rejection. This review discusses the therapeutic potential of human induced pluripotent stem cell-derived neural stem cell transplantation for treatment of spinal cord injury, as well as addressing potential mechanisms, future perspectives and challenges.

  1. Capsaicin-induced cell death in a human gastric adenocarcinoma cell line

    Institute of Scientific and Technical Information of China (English)

    Yi-Ching Lo; Yuan-Chen Yang; I-Chieh Wu; Fu-Chen Kuo; Chi-Ming Liu; Hao-Wei Wang; Chao-Hung Kuo; Jeng-Yi Wu; Deng-Chyang Wu

    2005-01-01

    AIM: Capsaicin, a pungent ingredient found in red pepper,has long been used in spices, food additives, and drugs.Cell death induced by the binding of capsaicin was examined in a human gastric adenocarcinoma cell line (AGS cells).METHODS: By using XTT-based cytotoxicityassay, flow cytometry using the TUNEL method, and quantitation of DNA fragmentation, both cell death and DNA fragmentation were detected in AGS cells treated with capsaicin. By using Western blotting methods, capsaicin reduced the expression of Bcl-2, the antiapoptotic protein, in AGS cells in a concentration-dependent manner.RESULTS: After incubation of AGS cells with capsaicin for 24 h, cell viability decreased significantly in a dose-dependent manner. After incubation of AGS cells with capsaicin for 24 h, apoptotic bodies also significantly increased, and were again correlated with the dose of capsaicin. When the concentration of capsaicin was 1 mmol/L, the amount of DNA fragments also increased. Similar results werealso in the lower traces.CONCLUSION: These results suggest that capsaicininduced cell death might be via a Bcl-2 sensitive apoptotic pathway. Therefore, capsaicin might induce protection from gastric cancer.

  2. In vitro antitumor immune response induced by fusion of dendritic cells and colon cancer cells

    Institute of Scientific and Technical Information of China (English)

    Feng Xu; Ying-Jiang Ye; Shan Wang

    2004-01-01

    AIM: The prevention of recurrence of colon cancer (CC)after operation is very important for improvement of the prognosis of CC patients, especially those with micrometastasis. The generation of fused cells between dendritic cells (DCs) and tumor cells maybe an effective approach for tumor antigen presentation in immunotherapy. In this study,we fused human colon caner SW480 cells and human peripheral blood - derived DCs to induce an antitumor activity against human CC.METHODS: CC SW480 cells and human peripheral blood derived DCs were fused with 500 mL/L polyethylene glycol (PEG).RESULTS: The specific T cell responses activated by fusion cells (FCs), were observed. About 100 mL/L to 160 mL/L of the PEG-treated non-adherent cells with fluorescences were considered to be dendritomas that highly expressed the key molecules for antigen presentation in our five cases. In vitro studies showed that fusions effectively activated CD8+ T lymphocytes to secrete interferon-γ. The early apoptotic ratio of the colon cancer SW480 cells was higher than that of controls, which was affected by cytotoxic T lymphocytes (CTLs) stimulated by dendritomas.CONCLUSION: The data indicate that fusion of tumor cells with DCs is an attractive strategy to induce tumor rejection.

  3. Big Animal Cloning Using Transgenic Induced Pluripotent Stem Cells: A Case Study of Goat Transgenic Induced Pluripotent Stem Cells.

    Science.gov (United States)

    Song, Hui; Li, Hui; Huang, Mingrui; Xu, Dan; Wang, Ziyu; Wang, Feng

    2016-02-01

    Using of embryonic stem cells (ESCs) could improve production traits and disease resistance by improving the efficiency of somatic cell nuclear transfer (SCNT) technology. However, robust ESCs have not been established from domestic ungulates. In the present study, we generated goat induced pluripotent stem cells (giPSCs) and transgenic cloned dairy goat induced pluripotent stem cells (tgiPSCs) from dairy goat fibroblasts (gFs) and transgenic cloned dairy goat fibroblasts (tgFs), respectively, using lentiviruses that contained hOCT4, hSOX2, hMYC, and hKLF4 without chemical compounds. The giPSCs and tgiPSCs expressed endogenous pluripotent markers, including OCT4, SOX2, MYC, KLF4, and NANOG. Moreover, they were able to maintain a normal karyotype and differentiate into derivatives from all three germ layers in vitro and in vivo. Using SCNT, tgFs and tgiPSCs were used as donor cells to produce embryos, which were named tgF-Embryos and tgiPSC-Embryos. The fusion rates and cleavage rates had no significant differences between tgF-Embryos and tgiPSC-Embryos. However, the expression of IGF-2, which is an important gene associated with embryonic development, was significantly lower in tgiPSC-Embryos than in tgF-Embryos and was not significantly different from vivo-Embryos.

  4. Fermi Large Area Telescope Observations of the Cosmic-Ray Induced

    Energy Technology Data Exchange (ETDEWEB)

    Abdo, A.

    2012-02-29

    We report on measurements of the cosmic-ray induced {gamma}-ray emission of Earth's atmosphere by the Large Area Telescope onboard the Fermi Gamma-ray Space Telescope. The LAT has observed the Earth during its commissioning phase and with a dedicated Earth-limb following observation in September 2008. These measurements yielded {approx} 6.4 x 10{sup 6} photons with energies > 100 MeV and {approx} 250 hours total livetime for the highest quality data selection. This allows the study of the spatial and spectral distributions of these photons with unprecedented detail. The spectrum of the emission - often referred to as Earth albedo gamma-ray emission - has a power-law shape up to 500 GeV with spectral index {Lambda} = 2.79 {+-} 0.06.

  5. Very Rapid and Efficient Generation of Induced Pluripotent Stem Cells from Mouse Pre-B Cells.

    Science.gov (United States)

    Di Stefano, Bruno; Graf, Thomas

    2016-01-01

    One of the major obstacles in generating induced pluripotent stem (iPS) cells suitable for therapeutic application is the low efficiency of the process and the long time required, with many iPS lines acquiring genomic aberrations. In this chapter we describe a highly efficient iPS reprogramming system based on the transient expression in pre-B cells of the transcription factor C/EBPα, followed by the induction of the four Yamanaka factors (OSKM). In addition, the process is very rapid, yielding Oct4 positive cells within 2 days and Nanog-positive iPS cell colonies within a week.

  6. Embryonic stem cell and induced pluripotent stem cell: an epigenetic perspective

    Institute of Scientific and Technical Information of China (English)

    Gaoyang Liang; Yi Zhang

    2013-01-01

    Pluripotent stem cells,like embryonic stem cells (ESCs),have specialized epigenetic landscapes,which are important for pluripotency maintenance.Transcription factor-mediated generation of induced pluripotent stem cells (iPSCs)requires global change of somatic cell epigenetic status into an ESC-like state.Accumulating evidence indicates that epigenetic mechanisms not only play important roles in the iPSC generation process,but also affect the properties of reprogrammed iPSCs.Understanding the roles of various epigenetic factors in iPSC generation contributes to our knowledge of the reprogramming mechanisms.

  7. Establishment of Human Neural Progenitor Cells from Human Induced Pluripotent Stem Cells with Diverse Tissue Origins.

    Science.gov (United States)

    Fukusumi, Hayato; Shofuda, Tomoko; Bamba, Yohei; Yamamoto, Atsuyo; Kanematsu, Daisuke; Handa, Yukako; Okita, Keisuke; Nakamura, Masaya; Yamanaka, Shinya; Okano, Hideyuki; Kanemura, Yonehiro

    2016-01-01

    Human neural progenitor cells (hNPCs) have previously been generated from limited numbers of human induced pluripotent stem cell (hiPSC) clones. Here, 21 hiPSC clones derived from human dermal fibroblasts, cord blood cells, and peripheral blood mononuclear cells were differentiated using two neural induction methods, an embryoid body (EB) formation-based method and an EB formation method using dual SMAD inhibitors (dSMADi). Our results showed that expandable hNPCs could be generated from hiPSC clones with diverse somatic tissue origins. The established hNPCs exhibited a mid/hindbrain-type neural identity and uniform expression of neural progenitor genes.

  8. Establishment of Human Neural Progenitor Cells from Human Induced Pluripotent Stem Cells with Diverse Tissue Origins

    Science.gov (United States)

    Fukusumi, Hayato; Shofuda, Tomoko; Bamba, Yohei; Yamamoto, Atsuyo; Kanematsu, Daisuke; Handa, Yukako; Okita, Keisuke; Nakamura, Masaya; Yamanaka, Shinya; Okano, Hideyuki; Kanemura, Yonehiro

    2016-01-01

    Human neural progenitor cells (hNPCs) have previously been generated from limited numbers of human induced pluripotent stem cell (hiPSC) clones. Here, 21 hiPSC clones derived from human dermal fibroblasts, cord blood cells, and peripheral blood mononuclear cells were differentiated using two neural induction methods, an embryoid body (EB) formation-based method and an EB formation method using dual SMAD inhibitors (dSMADi). Our results showed that expandable hNPCs could be generated from hiPSC clones with diverse somatic tissue origins. The established hNPCs exhibited a mid/hindbrain-type neural identity and uniform expression of neural progenitor genes. PMID:27212953

  9. Different Types of Cell Death Induced by Enterotoxins

    Directory of Open Access Journals (Sweden)

    Ming-Yuan Hong

    2010-08-01

    Full Text Available The infection of bacterial organisms generally causes cell death to facilitate microbial invasion and immune escape, both of which are involved in the pathogenesis of infectious diseases. In addition to the intercellular infectious processes, pathogen-produced/secreted enterotoxins (mostly exotoxins are the major weapons that kill host cells and cause diseases by inducing different types of cell death, particularly apoptosis and necrosis. Blocking these enterotoxins with synthetic drugs and vaccines is important for treating patients with infectious diseases. Studies of enterotoxin-induced apoptotic and necrotic mechanisms have helped us to create efficient strategies to use against these well-characterized cytopathic toxins. In this article, we review the induction of the different types of cell death from various bacterial enterotoxins, such as staphylococcal enterotoxin B, staphylococcal alpha-toxin, Panton-Valentine leukocidin, alpha-hemolysin of Escherichia coli, Shiga toxins, cytotoxic necrotizing factor 1, heat-labile enterotoxins, and the cholera toxin, Vibrio cholerae. In addition, necrosis caused by pore-forming toxins, apoptotic signaling through cross-talk pathways involving mitochondrial damage, endoplasmic reticulum stress, and lysosomal injury is discussed.

  10. Globular adiponectin induces differentiation and fusion of skeletal muscle cells

    Institute of Scientific and Technical Information of China (English)

    Tania Fiaschi; Domenico Cirelli; Giuseppina Comito; Stefania Gelmini; Giampietro Ramponi; Maria Serio; Paola Chiarugi

    2009-01-01

    The growing interest in skeletal muscle regeneration is associated with the opening of new therapeutic strategies for muscle injury after trauma, as well as several muscular degenerative pathologies, including dystrophies, muscu-lar atrophy, and cachexia. Studies focused on the ability of extracellular factors to promote myogenesis are therefore highly promising. We now report that an adipocyte-derived factor, globular adiponectin (gAd), is able to induce mus-cle gene expression and cell differentiation, gAd, besides its well-known ability to regulate several metabolic func-tions in muscle, including glucose uptake and consumption and fatty acid catabolism, is able to block cell cycle entry of myoblasts, to induce the expression of specific skeletal muscle markers such as myosin heavy chain or eaveolin-3, as well as to provoke cell fusion into multinucleated syneytia and, finally, muscle fibre formation, gAd exerts its pro-differentiative activity through redox-dependent activation of p38, Akt and 5'-AMP-activated protein kinase path-ways. Interestingly, differentiating myoblasts are autocrine for adiponectiu, and the mimicking of pro-inflammatory settings or exposure to oxidative stress strongly increases the production of the hormone from differentiating cells. These data suggest a novel function of adiponectin, directly coordinating the myogenic differentiation program and serving an autocrine function during skeletal myogenesis.

  11. Bortezomib induces autophagic death in proliferating human endothelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Belloni, Daniela; Veschini, Lorenzo [Myeloma Unit, Department of Oncology, IRCCS H San Raffaele, Milan (Italy); Foglieni, Chiara [Department of Cardiology, IRCCS H San Raffaele, Milan (Italy); Dell' Antonio, Giacomo [Department of Pathology, IRCCS H San Raffaele, Milan (Italy); Caligaris-Cappio, Federico [Myeloma Unit, Department of Oncology, IRCCS H San Raffaele, Milan (Italy); Universita Vita-Salute IRCCS H San Raffaele, Milan (Italy); Ferrarini, Marina [Myeloma Unit, Department of Oncology, IRCCS H San Raffaele, Milan (Italy); Ferrero, Elisabetta, E-mail: elisabetta.ferrero@hsr.it [Myeloma Unit, Department of Oncology, IRCCS H San Raffaele, Milan (Italy)

    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.

  12. Different types of cell death induced by enterotoxins.

    Science.gov (United States)

    Lin, Chiou-Feng; Chen, Chia-Ling; Huang, Wei-Ching; Cheng, Yi-Lin; Hsieh, Chia-Yuan; Wang, Chi-Yun; Hong, Ming-Yuan

    2010-08-01

    The infection of bacterial organisms generally causes cell death to facilitate microbial invasion and immune escape, both of which are involved in the pathogenesis of infectious diseases. In addition to the intercellular infectious processes, pathogen-produced/secreted enterotoxins (mostly exotoxins) are the major weapons that kill host cells and cause diseases by inducing different types of cell death, particularly apoptosis and necrosis. Blocking these enterotoxins with synthetic drugs and vaccines is important for treating patients with infectious diseases. Studies of enterotoxin-induced apoptotic and necrotic mechanisms have helped us to create efficient strategies to use against these well-characterized cytopathic toxins. In this article, we review the induction of the different types of cell death from various bacterial enterotoxins, such as staphylococcal enterotoxin B, staphylococcal alpha-toxin, Panton-Valentine leukocidin, alpha-hemolysin of Escherichia coli, Shiga toxins, cytotoxic necrotizing factor 1, heat-labile enterotoxins, and the cholera toxin, Vibrio cholerae. In addition, necrosis caused by pore-forming toxins, apoptotic signaling through cross-talk pathways involving mitochondrial damage, endoplasmic reticulum stress, and lysosomal injury is discussed.

  13. From cloned frogs to patient matched stem cells: induced pluripotency or somatic cell nuclear transfer?

    Science.gov (United States)

    Yamada, Mitsutoshi; Byrne, James; Egli, Dieter

    2015-10-01

    Nuclear transfer has seen a remarkable comeback in the past few years. Three groups have independently reported the derivation of stem cell lines by somatic cell nuclear transfer, from either adult, neonatal or fetal cells. Though the ability of human oocytes to reprogram somatic cells to stem cells had long been anticipated, success did not arrive on a straightforward path. Little was known about human oocyte biology, and nuclear transfer protocols developed in animals required key changes to become effective with human eggs. By overcoming these challenges, human nuclear transfer research has contributed to a greater understanding of oocyte biology, provided a point of reference for the comparison of induced pluripotent stem cells, and delivered a method for the generation of personalized stem cells with therapeutic potential.

  14. Mesenchymal stem cells and induced pluripotent stem cells as therapies for multiple sclerosis.

    Science.gov (United States)

    Xiao, Juan; Yang, Rongbing; Biswas, Sangita; Qin, Xin; Zhang, Min; Deng, Wenbin

    2015-04-24

    Multiple sclerosis (MS) is a chronic, autoimmune, inflammatory demyelinating disorder of the central nervous system that leads to permanent neurological deficits. Current MS treatment regimens are insufficient to treat the irreversible neurological disabilities. Tremendous progress in the experimental and clinical applications of cell-based therapies has recognized stem cells as potential candidates for regenerative therapy for many neurodegenerative disorders including MS. Mesenchymal stem cells (MSC) and induced pluripotent stem cell (iPSCs) derived precursor cells can modulate the autoimmune response in the central nervous system (CNS) and promote endogenous remyelination and repair process in animal models. This review highlights studies involving the immunomodulatory and regenerative effects of mesenchymal stem cells and iPSCs derived cells in animal models, and their translation into immunomodulatory and neuroregenerative treatment strategies for MS.

  15. Mesenchymal Stem Cells and Induced Pluripotent Stem Cells as Therapies for Multiple Sclerosis

    Directory of Open Access Journals (Sweden)

    Juan Xiao

    2015-04-01

    Full Text Available Multiple sclerosis (MS is a chronic, autoimmune, inflammatory demyelinating disorder of the central nervous system that leads to permanent neurological deficits. Current MS treatment regimens are insufficient to treat the irreversible neurological disabilities. Tremendous progress in the experimental and clinical applications of cell-based therapies has recognized stem cells as potential candidates for regenerative therapy for many neurodegenerative disorders including MS. Mesenchymal stem cells (MSC and induced pluripotent stem cell (iPSCs derived precursor cells can modulate the autoimmune response in the central nervous system (CNS and promote endogenous remyelination and repair process in animal models. This review highlights studies involving the immunomodulatory and regenerative effects of mesenchymal stem cells and iPSCs derived cells in animal models, and their translation into immunomodulatory and neuroregenerative treatment strategies for MS.

  16. Changes of PIG3 Expression and Cell Cycle of AHH-1 Cells Induced by Fast Neutrons

    Institute of Scientific and Technical Information of China (English)

    SUI; Li; MA; Nan-ru; KONG; Fu-quan; WANG; Xiao; ZHANG; Xiao-ling; CHEN; Hong-tao

    2013-01-01

    Biological dosimeter has unique advantages for the detection of human body damage induced by nuclear radiation.PIG3 is DNA damage inducible gene located downstream of the p53(tumor suppressor gene),which appears at the early stage after radiation and is associated with cell apoptosis.PIG3expression can be measured by modern molecular biological technology and is suitable for quick doses

  17. Cytoskeletal changes induced by allosteric modulators of calcium-sensing receptor in esophageal epithelial cells.

    Science.gov (United States)

    Abdulnour-Nakhoul, Solange; Brown, Karen L; Rabon, Edd C; Al-Tawil, Youhanna; Islam, Mohammed T; Schmieg, John J; Nakhoul, Nazih L

    2015-11-01

    The calcium-sensing receptor (CaSR), a G-protein-coupled receptor, plays a role in glandular and fluid secretion in the gastrointestinal tract, and regulates differentiation and proliferation of epithelial cells. We examined the expression of CaSR in normal and pathological conditions of human esophagus and investigated the effect of a CaSR agonist, cinacalcet (CCT), and antagonist, calhex (CHX), on cell growth and cell-cell junctional proteins in primary cultures of porcine stratified squamous esophageal epithelium. We used immunohistochemistry and Western analysis to monitor expression of CaSR and cell-cell adhesion molecules, and MTT assay to monitor cell proliferation in cultured esophageal cells. CCT treatment significantly reduced proliferation, changed the cell shape from polygonal to spindle-like, and caused redistribution of E-cadherin and β-catenin from the cell membrane to the cytoplasm. Furthermore, it reduced expression of β-catenin by 35% (P < 0.02) and increased expression of a proteolysis cleavage fragment of E-cadherin, Ecad/CFT2, by 2.3 folds (P < 0.01). On the other hand, CHX treatment enhanced cell proliferation by 27% (P < 0.01), increased the expression of p120-catenin by 24% (P < 0.04), and of Rho, a GTPase involved in cytoskeleton remodeling, by 18% (P < 0.03). In conclusion, CaSR is expressed in normal esophagus as well as in Barrett's, esophageal adenocarcinoma, squamous cell carcinoma, and eosinophilic esophagitis. Long-term activation of CaSR with CCT disrupted the cadherin-catenin complex, induced cytoskeletal remodeling, actin fiber formation, and redistribution of CaSR to the nuclear area. These changes indicate a significant and complex role of CaSR in epithelial remodeling and barrier function of esophageal cells.

  18. Neural progenitor cells from human induced pluripotent stem cells generated less autogenous immune response.

    Science.gov (United States)

    Huang, Ke; Liu, PengFei; Li, Xiang; Chen, ShuBin; Wang, LiHui; Qin, Li; Su, ZhengHui; Huang, WenHao; Liu, Juli; Jia, Bei; Liu, Jie; Cai, JingLei; Pei, DuanQing; Pan, GuangJin

    2014-02-01

    The breakthrough development of induced pluripotent stem cells (iPSCs) raises the prospect of patient-specific treatment for many diseases through the replacement of affected cells. However, whether iPSC-derived functional cell lineages generate a deleterious immune response upon auto-transplantation remains unclear. In this study, we differentiated five human iPSC lines from skin fibroblasts and urine cells into neural progenitor cells (NPCs) and analyzed their immunogenicity. Through co-culture with autogenous peripheral blood mononuclear cells (PBMCs), we showed that both somatic cells and iPSC-derived NPCs do not stimulate significant autogenous PBMC proliferation. However, a significant immune reaction was detected when these cells were co-cultured with allogenous PBMCs. Furthermore, no significant expression of perforin or granzyme B was detected following stimulation of autogenous immune effector cells (CD3(+)CD8(-) T cells, CD3(+)CD8(+) T cells or CD3(-)CD56(+) NK cells) by NPCs in both PBMC and T cell co-culture systems. These results suggest that human iPSC-derived NPCs may not initiate an immune response in autogenous transplants, and thus set a base for further preclinical evaluation of human iPSCs.

  19. Docosahexaenoic acid induces apoptosis in primary chronic lymphocytic leukemia cells

    Directory of Open Access Journals (Sweden)

    Romain Guièze

    2015-12-01

    Full Text Available Chronic lymphocytic leukemia is an indolent disorder with an increased infectious risk remaining one of the main causes of death. Development of therapies with higher safety profile is thus a challenging issue. Docosahexaenoic acid (DHA, 22:6 is an omega-3 fatty acid, a natural compound of normal cells, and has been shown to display antitumor potency in cancer. We evaluated the potential in vitro effect of DHA in primary CLL cells. DHA induces high level of in vitro apoptosis compared to oleic acid in a dose-dependent and time-dependent manner. Estimation of IC50 was only of 4.813 μM, which appears lower than those reported in solid cancers. DHA is highly active on CLL cells in vitro. This observation provides a rationale for further studies aiming to understand its mechanisms of action and its potent in vivo activity.

  20. Light-induced performance increase of silicon heterojunction solar cells

    KAUST Repository

    Kobayashi, Eiji

    2016-10-11

    Silicon heterojunction solar cells consist of crystalline silicon (c-Si) wafers coated with doped/intrinsic hydrogenated amorphous silicon (a-Si:H) bilayers for passivating-contact formation. Here, we unambiguously demonstrate that carrier injection either due to light soaking or (dark) forward-voltage bias increases the open circuit voltage and fill factor of finished cells, leading to a conversion efficiency gain of up to 0.3% absolute. This phenomenon contrasts markedly with the light-induced degradation known for thin-film a-Si:H solar cells. We associate our performance gain with an increase in surface passivation, which we find is specific to doped a-Si:H/c-Si structures. Our experiments suggest that this improvement originates from a reduced density of recombination-active interface states. To understand the time dependence of the observed phenomena, a kinetic model is presented.

  1. Effects of coil orientation on the electric field induced by TMS over the hand motor area.

    Science.gov (United States)

    Laakso, Ilkka; Hirata, Akimasa; Ugawa, Yoshikazu

    2014-01-01

    Responses elicited by transcranial magnetic stimulation (TMS) over the hand motor area depend on the position and orientation of the stimulating coil. In this work, we computationally investigate the induced electric field for multiple coil orientations and locations in order to determine which parts of the brain are affected and how the sensitivity of motor cortical activation depends on the direction of the electric field. The finite element method is used for calculating the electric field induced by TMS in two individual anatomical models of the head and brain. The orientation of the coil affects both the strength and depth of penetration of the electric field, and the field strongly depends on the direction of the sulcus, where the target neurons are located. The coil position that gives the strongest electric field in the target cortical region may deviate from the closest scalp location by a distance on the order of 1 cm. Together with previous experimental data, the results support the hypothesis that the cortex is most sensitive to fields oriented perpendicular to the cortical layers, while it is relatively insensitive to fields parallel to them. This has important implications for targeting of TMS. To determine the most effective coil position and orientation, it is essential to consider both biological (the direction of the targeted axons) and physical factors (the strength and direction of the electric field).

  2. Hypoxia-induced hypothermia mediated by the glutamatergic transmission in the lateral preoptic area.

    Science.gov (United States)

    Osaka, T

    2012-12-13

    Hypoxia evokes a regulated decrease in the body core temperature, which response is mediated, at least in part, by noradrenaline (NA) and nitric oxide (NO) in the rostromedial preoptic area (POA) of the hypothalamus. In the accompanying paper, it was shown that glutamatergic activation of the lateral POA also evokes hypothermic responses. Here, I tested the hypothesis that the glutamatergic transmission in the lateral POA is critically involved in the neural mechanism of hypoxia-induced hypothermia. Hypoxic ventilation (10% O(2)-90% N(2), 5 min) as well as a single microinjection of NA (50 pmol) or the NO donor sodium nitroprusside (8.4 nmol) into the rostromedial POA evoked an increase in the tail skin temperature and a decrease in the colonic temperature in urethane-chloralose-anesthetized, neuromuscularly blocked, artificially ventilated rats. All of these responses were greatly attenuated by pretreatment with multiple microinjections of kynurenic acid (10 nmol, four locations), a nonselective glutamate receptor antagonist, but not by those with saline solution, in the bilateral rostral and central parts of the lateral POA. These results suggest that the NA- and NO-sensitive structure in the rostromedial POA activated the glutamatergic transmission in the lateral POA to mediate hypoxia-induced hypothermia.

  3. Proteasome inhibition-induces endoplasmic reticulum dysfunction and cell death of human cholangiocarcinoma cells

    Institute of Scientific and Technical Information of China (English)

    Yucel Ustundag; Steven F Bronk; Gregory J Gores

    2007-01-01

    AIM: To determine if proteasome inhibition induces apoptosis in human cholangiocarcinoma cells, and if so, to elucidate the cellular mechanisms.METHODS: Studies were performed in the human KMCH, KMBC, and Mz-ChA-1 cholangiocarcinoma, and normal rat cell lines. MG132, a peptide aldehyde, which inhibits the chymotrypsin-like activity of the proteaosome was employed for this study. Apoptosis was assessed morphologically by 4'-6-Diamidino-2-phenylindole (DAPI) nuclear staining and fluorescence microscopy. Mitochondrial membrane potential was examined using a fluorescent unquenching assay. Ultrastructural changes during cell death were examined using transmission electron microscopy (TEM). Caspase 3/7 activity was assessed using an enzymatic-based fluorescent assay. Cytosolic-free calcium concentrations were measured using Fura-2 and digitized fluorescent microscopy.RESULTS: MG132, a proteasome inhibitor, induced apoptosis in all the cholangiocarcinoma cell lines examined. In contrast, minimal cytotoxicity was observed in normal rat cholangiocytes. Apoptosis was time- and -concentration-dependent. There was no change in the mitochondrial membrane potential between treated and untreated cells. Ultrastructural examination by transmission electron microscopy displayed the classic features of apoptosis, but in addition, there was also dramatic vacuolization of the endoplasmic reticulum (ER). Unexpectedly, no increase in caspase 3/7 activity was observed in MG132 treated cells, nor did the pancaspase inhibitor, Q-VD-OPh prevent cell death. The protein synthesis inhibitor, cycloheximide, blocked apoptosis induced by proteosome inhibitor indicating that ER dysfunction was dependent upon the formation of new proteins.CONCLUSION:Proteosome inhibition induces ER dysfunction and caspase-independent cell death selectively in human cholangiocarcinoma cells. Proteasome inhibitors warrant evaluation as anticancer agents for the treatment of human cholangiocarcinoma.

  4. The Characteristics of Amiodarone-induced Thyrotoxicosis in a Moderate Iodine Deficit Area

    Directory of Open Access Journals (Sweden)

    Ancuța-Elena Cota

    2013-08-01

    Full Text Available Introduction: Amiodarone (AMI, a class III anti-arrhythmic drug, is associated with a number of side effects, including thyroid dysfunction (both hypo- and hyperthyroidism, which is due to amiodarone's high iodine content and its direct toxic effect on the thyroid. Objective: To evaluate the incidence of Amiodarone induced thyrotoxicosis (AIT (type, rate of occurrence and to identify the risk factors involved in its occurrence. Material and method: We examined patients treated with amiodarone, between January 2002 and December 2011, who presented to our Department of Endocrinology Târgu Mures for thyroid dysfunctions. Results: The retrospective study included 87 patients with thyroid dysfunctions; 58 (66.7% patients had AIT and 29 (33.3% had Amiodarone induced hypothyroidism (AIH. In the AIT group: 35 were women (60.3%, 23 were men (39.7%; the average age was 61.60 ± 12.39 years. Risk factors identified for the AIT group were male gender (RR = OR = 3.8; Chi-squer = 5.7, p = 0.004 and pre-existing thyroid abnormalities (RR = 2.5, Chi-square = 4.1, p = 0.005. The thyroid dysfunction occurrence was heterogeneous (0.2-183 months. The patients with previous thyroid abnormalities developed earlier thyroid dysfunction compared to those with an apparently normal thyroid gland (22.25 ± 4.14 months versus 32.09 ± 7.69 months, p = 0.02, T test. Conclusion: In the context of the specific iodine geoclimatic intake and the area of origin, amiodarone - induced thyroid dysfunction spectrum is dominated by thyrotoxicosis. Screening and monitoring of thyroid function for patiens under chronic amiodarone treatment is necessary

  5. An improved protocol that induces human embryonic stem cells to differentiate into neural cells in vitro.

    Science.gov (United States)

    Zhou, Jun-Mei; Chu, Jian-Xin; Chen, Xue-Jin

    2008-01-01

    Human embryonic stem (ES) cells have the capacity for self-renewal and are able to differentiate into any cell type. However, obtaining high-efficient neural differentiation from human ES cells remains a challenge. This study describes an improved 4-stage protocol to induce a human ES cell line derived from a Chinese population to differentiate into neural cells. At the first stage, embryonic bodies (EBs) were formed in a chemically-defined neural inducing medium rather than in traditional serum or serum-replacement medium. At the second stage, rosette-like structures were formed. At the third stage, the rosette-like structures were manually selected rather than enzymatically digested to form floating neurospheres. At the fourth stage, the neurospheres were further differentiated into neurons. The results show that, at the second stage, the rate of the formation of rosette-like structures from EBs induced by noggin was 88+/-6.32%, higher than that of retinoic acid 55+/-5.27%. Immunocytochemistry staining was used to confirm the neural identity of the cells. These results show a major improvement in obtaining efficient neural differentiation of human ES cells.

  6. Pogostemon cablin as ROS Scavenger in Oxidant-Induced Cell Death of Human Neuroglioma Cells

    Directory of Open Access Journals (Sweden)

    Hyung Woo Kim

    2010-01-01

    Full Text Available Reactive oxygen species (ROS have been implicated in the pathogenesis of a wide range of acute and long-term neurodegenerative diseases. This study was undertaken to examine the efficacy of Pogostemon cablin, a well-known herb in Korean traditional medicine, on ROS-induced brain cell injury. Pogostemon cablin effectively protected human neuroglioma cell line A172 against both the necrotic and apoptotic cell death induced by hydrogen peroxide (H2O2. The effect of Pogostemon cablin was dose dependent at concentrations ranging from 0.2 to 5 mg ml−1. Pogostemon cablin significantly prevented depletion of cellular ATP and activation of poly ADP-ribose polymerase induced by H2O2. The preservation of functional integrity of mitochondria upon the treatment of Pogostemon cablin was also confirmed by 3-(4,5-dimethyl-2-thiazyl-2,5-diphenyl-2-H-tetrazolium bromide assay. Furthermore, Pogostemon cablin significantly prevented H2O2-induced release of cytochrome c into cytosol. Determination of intracellular ROS showed that Pogostemon cablin might exert its role as a powerful scavenger of intracellular ROS. The present study suggests the beneficial effect of Pogostemon cablin on ROS-induced neuroglial cell injury. The action of Pogostemon cablin as a ROS-scavenger might underlie the mechanism.

  7. Environmentally induced programmed cell death in leaf protoplasts of Aponogeton madagascariensis.

    Science.gov (United States)

    Lord, Christina E N; Gunawardena, Arunika H L A N

    2011-02-01

    Within plant systems, two main forms of programmed cell death (PCD) exist: developmentally regulated and environmentally induced. The lace plant (Aponogeton madagascariensis) naturally undergoes developmentally regulated PCD to form perforations between longitudinal and transverse veins over its leaf surface. Developmental PCD in the lace plant has been well characterized; however, environmental PCD has never before been studied in this plant species. The results presented here portray heat shock (HS) treatment at 55 °C for 20 min as a promising inducer of environmental PCD within lace plant protoplasts originally isolated from non-PCD areas of the plant. HS treatment produces cells displaying many characteristics of developmental PCD, including blebbing of the plasma membrane, increased number of hydrolytic vesicles and transvacuolar strands, nuclear condensation, terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling positive nuclei, as well as increased Brownian motion within the vacuole. Results presented here for the first time provide evidence of chloroplasts in the vacuole of living protoplasts undergoing environmentally induced PCD. Findings suggest that the mitochondria play a critical role in the cell death process. Changes in mitochondrial dynamics were visualized in HS-treated cells, including loss of mitochondrial mobility, reduction in ΔΨ(m), as well as the proximal association with chloroplasts. The role of the mitochondrial permeability transition pore (PTP) was examined by pre-treatment with the PTP agonist cyclosporine A. Overall, HS is depicted as a reliable method to induce PCD within lace plant protoplasts, and proves to be a reliable technique to enable comparisons between environmentally induced and developmentally regulated PCD within one species of plant.

  8. T-cell reconstitution after thymus xenotransplantation induces hair depigmentation and loss.

    Science.gov (United States)

    Furmanski, Anna L; O'Shaughnessy, Ryan F L; Saldana, Jose Ignacio; Blundell, Michael P; Thrasher, Adrian J; Sebire, Neil J; Davies, E Graham; Crompton, Tessa

    2013-05-01

    Here we present a mouse model for T-cell targeting of hair follicles, linking the pathogenesis of alopecia to that of depigmentation disorders. Clinically, thymus transplantation has been successfully used to treat T-cell immunodeficiency in congenital athymia, but is associated with autoimmunity. We established a mouse model of thymus transplantation by subcutaneously implanting human thymus tissue into athymic C57BL/6 nude mice. These xenografts supported mouse T-cell development. Surprisingly, we did not detect multiorgan autoimmune disease. However, in all transplanted mice, we noted a striking depigmentation and loss of hair follicles. Transfer of T cells from transplanted nudes to syngeneic black-coated RAG(-/-) recipients caused progressive, persistent coat-hair whitening, which preceded patchy hair loss in depigmented areas. Further transfer experiments revealed that these phenomena could be induced by CD4+ T cells alone. Immunofluorescent analysis suggested that Trp2+ melanocyte-lineage cells were decreased in depigmented hair follicles, and pathogenic T cells upregulated activation markers when exposed to C57BL/6 melanocytes in vitro, suggesting that these T cells are not tolerant to self-melanocyte antigens. Our data raise interesting questions about the mechanisms underlying tissue-specific tolerance to skin antigens.

  9. Differences in the microrheology of human embryonic stem cells and human induced pluripotent stem cells.

    Science.gov (United States)

    Daniels, Brian R; Hale, Christopher M; Khatau, Shyam B; Kusuma, Sravanti; Dobrowsky, Terrence M; Gerecht, Sharon; Wirtz, Denis

    2010-12-01

    Embryonic and adult fibroblasts can be returned to pluripotency by the expression of reprogramming genes. Multiple lines of evidence suggest that these human induced pluripotent stem (hiPS) cells and human embryonic stem (hES) cells are behaviorally, karyotypically, and morphologically similar. Here we sought to determine whether the physical properties of hiPS cells, including their micromechanical properties, are different from those of hES cells. To this end, we use the method of particle tracking microrheology to compare the viscoelastic properties of the cytoplasm of hES cells, hiPS cells, and the terminally differentiated parental human fibroblasts from which our hiPS cells are derived. Our results indicate that although the cytoplasm of parental fibroblasts is both viscous and elastic, the cytoplasm of hiPS cells does not exhibit any measurable elasticity and is purely viscous over a wide range of timescales. The viscous phenotype of hiPS cells is recapitulated in parental cells with disassembled actin filament network. The cytoplasm of hES cells is predominantly viscous but contains subcellular regions that are also elastic. This study supports the hypothesis that intracellular elasticity correlates with the degree of cellular differentiation and reveals signif