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Sample records for benzopyrene exposed cells

  1. DNA methylation analysis using CpG microarrays is impaired in benzopyrene exposed cells

    SciTech Connect

    Sadikovic, Bekim; Andrews, Joseph; Rodenhiser, David I.

    2007-12-15

    Epigenetic alterations have emerged as a key mechanism involved in tumorigenesis. These disruptions are partly due to environmental factors that change normal DNA methylation patterns necessary for transcriptional regulation and chromatin compaction. Microarray technologies are allowing environmentally susceptible epigenetic patterns to be mapped and the precise targets of environmentally induced alterations to be identified. Previously, we observed BaP-induced epigenetic events and cell cycle disruptions in breast cancer cell lines that included time- and concentration-dependent loss of proliferation as well as sequence-specific hypo- and hypermethylation events. In this present report, we further characterized epigenetic changes in BaP-exposed MCF-7 cells. We analyzed DNA methylation on a CpG island microarray platform with over 5400 unique genomic regions. Depleted and enriched microarray targets, representative of putative DNA methylation changes, were identified across the genome; however, subsequent sodium bisulfite analyses revealed no changes in DNA methylation at a number of these loci. Instead, we found that the identification of DNA methylation changes using this restriction enzyme-based microarray approach corresponded with the regions of DNA bound by the BaP derived DNA adducts. This DNA adduct formation occurs at both methylated and unmethylated CpG dinucleotides and affects PCR amplification during sample preparation. Our data suggest that caution should be exercised when interpreting data from comparative microarray experiments that rely on enzymatic reactions. These results are relevant to genome screening approaches involving environmental exposures in which DNA adduct formation at specific nucleotide sites may bias target acquisition and compromise the correct identification of epigenetically responsive genes.

  2. Benzopyrene and Experimental Stressors Cause Compensatory Differentiation in Placental Trophoblast Stem Cells

    PubMed Central

    Rappolee, Daniel A.; Awonuga, Awoniyi O.; Puscheck, Elizabeth E.; Zhou, Sichang; Xie, Yufen

    2013-01-01

    Stress causes decreased cell accumulation in early periimplantation embryos and the placental trophoblast stem cells derived from them. Benzopyrene and many other stressors activate stress enzymes that lead to suppressed stem cell accumulation through diminished proliferation and increased apoptosis. Trophoblast stem cells proliferate and a subpopulation of early postimplantation trophoblast cells differentiate to produce the first placental hormones that arise in the implanting conceptus. These hormones mediate antiluteolytic effects that enable the continuation of a successful implantation. The normal determination and differentiation of placental trophoblast stem cells is dependent upon a series of transcription factors. But, these transcription factors can also be modulated by stress through the activity of stress enzymes. This review enumerates and analyzes recent reports on the effects of benzopyrene on placental function in terms of the emerging paradigm that placental differentiation from stem cells can be regulated when insufficient production of stem cells is caused by stress. In addition, we review the other effects caused by benzopyrene throughout placental development. PMID:20377314

  3. Benzopyrene exposure disrupts DNA methylation and growth dynamics in breast cancer cells

    SciTech Connect

    Sadikovic, Bekim; Rodenhiser, David I. . E-mail: drodenhi@uwo.ca

    2006-11-01

    Exposures to environmental carcinogens and unhealthy lifestyle choices increase the incidence of breast cancer. One such compound, benzo(a)pyrene (BaP), leads to covalent DNA modifications and the deregulation of gene expression. To date, these mechanisms of BaP-induced carcinogenesis are poorly understood, particularly in the case of breast cancer. We tested the effects of BaP exposure on cellular growth dynamics and DNA methylation in four breast cancer cell lines since disruptions in DNA methylation lead to deregulated gene expression and the loss of genomic integrity. We observed robust time- and concentration-dependent loss of proliferation, S phase and G2M accumulation and apoptosis in p53 positive MCF-7 and T47-D cells. We observed minimal responses in p53 negative HCC-1086 and MDA MB 231 cells. Furthermore, BaP increased p53 levels in both p53 positive cell lines, as well as p21 levels in MCF-7 cells, an effect that was prevented by the p53-specific inhibitor pifithrin-{alpha}. No changes in global levels of DNA methylation levels induced by BaP were detected by the methyl acceptor assay (MAA) in any cell line, however, methylation profiling by AIMS (amplification of intermethylated sites) analysis showed dynamic, sequence-specific hypo- and hypermethylation events in all cell lines. We also identified BaP-induced hypomethylation events at a number of genomic repeats. Our data confirm the p53-specific disruption of the cell cycle as well as the disruption of DNA methylation as a consequence of BaP treatment, thus reinforcing the link between environmental exposures, DNA methylation and breast cancer.

  4. Benzopyrene promotes lung cancer A549 cell migration and invasion through up-regulating cytokine IL8 and chemokines CCL2 and CCL3 expression

    PubMed Central

    Zhang, Jin; Chang, Li; Jin, Hanyu; Xia, Yaoxiong; Wang, Li; He, Wenjie; Chen, Hong

    2016-01-01

    Tobacco-sourced carcinogen including benzopyrene (B[a]P) in lung cancer metastasis has not been fully reported. In this study, lung carcinoma A549 cell line was used to investigate the potential roles of tobacco-sourced B[a]P on cell metastasis and invasion and to assess its underlying mechanism. Effects of tobacco-sourced carcinogen on A549 cell proliferation, metastasis, and invasion were analyzed using MTT assay, Transwell assay, and scratch method, respectively. The effects of tobacco-sourced carcinogen on cytokines and chemokines secretion were detected using enzyme-linked immunosorbent assay. Moreover, correlation between inflammatory factor expression and cancer cell migration and invasion was assessed using siRNA-mediated gene silencing. Data showed that both B[a]P and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone either at high or low dose performed no significant difference on A549 cell proliferation with time increasing. 4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanone performed no significant difference on A549 cell migration and invasion while B[a]P significantly increased A549 cell migration and invasion compared to the control group (P < 0.05). Consequently, except for IL-6, IL-8, CCL-2, and CCL-3, secretions were significantly increased by B[a]P treatment compared to the control (P < 0.05). Furthermore, when CCL-2 and CCL-3 were silenced, the migrated and invasive A549 cells were significantly decreased compared to the control, respectively (P < 0.05), while silenced IL-8 drastically decreased the migrated and invasive cells compared to the control (P < 0.01). Taken together, this study illustrated that there may be significant correlation between smoking and lung cancer metastasis. B[a]P maybe an excellent contributor for lung cancer metastasis through up-regulating IL-8, CCL-2, and CCL-3 expression. PMID:27075927

  5. Macrophages promote benzopyrene-induced tumor transformation of human bronchial epithelial cells by activation of NF-κB and STAT3 signaling in a bionic airway chip culture and in animal models

    PubMed Central

    Sun, Zhao; Wang, Lei; Guo, Zhe; Zhao, Yang; Gao, Zhancheng; Wang, Qi

    2015-01-01

    We investigated the role of macrophages in promoting benzopyrene (BaP)-induced malignant transformation of human bronchial epithelial cells using a BaP-induced tumor transformation model with a bionic airway chip in vitro and in animal models. The bionic airway chip culture data showed that macrophages promoted BaP-induced malignant transformation of human bronchial epithelial cells, which was mediated by nuclear factor (NF)-κB and STAT3 pathways to induce cell proliferation, colony formation in chip culture, and tumorigenicity in nude mice. Blockage of interleukin (IL)-6 or tumor necrosis factor (TNF)-α signaling or inhibition of NF-κB, STAT3, or cyclinD1 expression abrogated the effect of macrophages on malignant transformation in the bionic airway chip culture. In vivo, macrophages promoted lung tumorigenesis in a carcinogen-induced animal model. Similarly, blockage of NF-κB, STAT3, or cyclinD1 using siRNA transfection decreased the carcinogen-induced tumorigenesis in rats. We demonstrated that macrophages are critical in promoting lung tumorigenesis and that the macrophage-initiated TNF-α/NF-κB/cyclinD1 and IL-6/STAT3/cyclinD1 pathways are primarily responsible for promoting lung tumorigenesis. PMID:25823926

  6. Macrophages promote benzopyrene-induced tumor transformation of human bronchial epithelial cells by activation of NF-κB and STAT3 signaling in a bionic airway chip culture and in animal models.

    PubMed

    Li, Encheng; Xu, Zhiyun; Zhao, Hui; Sun, Zhao; Wang, Lei; Guo, Zhe; Zhao, Yang; Gao, Zhancheng; Wang, Qi

    2015-04-20

    We investigated the role of macrophages in promoting benzopyrene (BaP)-induced malignant transformation of human bronchial epithelial cells using a BaP-induced tumor transformation model with a bionic airway chip in vitro and in animal models. The bionic airway chip culture data showed that macrophages promoted BaP-induced malignant transformation of human bronchial epithelial cells, which was mediated by nuclear factor (NF)-κB and STAT3 pathways to induce cell proliferation, colony formation in chip culture, and tumorigenicity in nude mice. Blockage of interleukin (IL)-6 or tumor necrosis factor (TNF)-α signaling or inhibition of NF-κB, STAT3, or cyclinD1 expression abrogated the effect of macrophages on malignant transformation in the bionic airway chip culture. In vivo, macrophages promoted lung tumorigenesis in a carcinogen-induced animal model. Similarly, blockage of NF-κB, STAT3, or cyclinD1 using siRNA transfection decreased the carcinogen-induced tumorigenesis in rats. We demonstrated that macrophages are critical in promoting lung tumorigenesis and that the macrophage-initiated TNF-α/NF-κB/cyclinD1 and IL-6/STAT3/cyclinD1 pathways are primarily responsible for promoting lung tumorigenesis.

  7. Functional role and mechanism of lncRNA LOC728228 in malignant 16HBE cells transformed by anti-benzopyrene-trans-7,8-dihydrodiol-9,10-epoxide.

    PubMed

    Hu, Gongcheng; Yang, Ti; Zheng, Jingli; Dai, Jiabing; Nan, Aruo; Lai, Yandong; Zhang, Yajie; Yang, Chengfeng; Jiang, Yiguo

    2015-06-01

    Lung cancer is a major health problem, and is considered one of the deadliest cancers in humans. It is refractory to current treatments, and the mechanisms of lung cancer are unknown. Long noncoding RNAs (lncRNAs) are involved in various biological processes and human diseases. However, the exact functional roles and mechanisms of lncRNAs are largely unclear. In this study, we attempted to identify lung-cancer-related lncRNAs. We found changes in lncRNA expression in the anti-benzo(a) pyrene-7,8-diol-9,10-epoxide (anti-BPDE)-transformed human bronchial epithelial cell line (16HBE-T cells) using microarrays and qRT-PCR. Of these lncRNAs, LOC728228 was upregulated relative to its expression in control untransformed16HBE (16HBE-N) cells. LOC728228 knockdown inhibited cell proliferation, caused G0/G1-phase cell-cycle arrest, reduced cellular migration, suppressed colony formation in vitro, and inhibited tumor growth in a nude mouse xenograft model. LOC728228 knockdown also suppressed cyclin D1 expression, and the depletion of cyclin D1 induced G0/G1-phase cell-cycle arrest and inhibited cell proliferation, thus influencing the malignant potential of cancer cells. In summary, our results suggest that lncRNA LOC728228 has an oncogene-like function and plays a vital role in human lung cancer. © 2015 Wiley Periodicals, Inc.

  8. [Determination of 3, 4-benzopyrene in spiruline algae produced and treated by various procedures].

    PubMed

    Bories, G; Tulliez, J

    1975-01-01

    Spirulina algae grow in highly salted natural lakes. Artificial cultivation in tanks with addition of carbon dioxide (natural gas, burned gases) has been studied in order to improve the biosynthesis. A possible 3, 4-benzopyrene (BaP) contamination must be then considered. Several BaP determinations have been performed in batches of algae from bath origins, prepared following different processes (filtration, spray, cylinder drying). BaP contents are very low (2 to 3 ppb) and comparable between batches.

  9. Ozone exposed epithelial cells modify cocultured natural killer cells

    PubMed Central

    Müller, Loretta; Brighton, Luisa E.

    2013-01-01

    Ozone (O3) causes significant adverse health effects worldwide. Nasal epithelial cells (NECs) are among the first sites within the respiratory system to be exposed to inhaled air pollutants. They recruit, activate, and interact with immune cells via soluble mediators and direct cell-cell contacts. Based on our recent observation demonstrating the presence of natural killer (NK) cells in nasal lavages, the goal of this study was to establish a coculture model of NECs and NK cells and examine how exposure to O3 modifies this interaction. Flow cytometry analysis was used to assess immunophenotypes of NK cells cocultured with either air- or O3-exposed NECs. Our data show that coculturing NK cells with O3-exposed NECs decreased intracellular interferon-γ (IFN-γ), enhanced, albeit not statistically significant, IL-4, and increased CD16 expression on NK cells compared with air controls. Additionally, the cytotoxicity potential of NK cells was reduced after coculturing with O3-exposed NECs. To determine whether soluble mediators released by O3-exposed NECs caused this shift, apical and basolateral supernatants of air- and O3-exposed NECs were used to stimulate NK cells. While the conditioned media of O3-exposed NECs alone did not reduce intracellular IFN-γ, O3 enhanced the expression of NK cell ligands ULBP3 and MICA/B on NECs. Blocking ULBP3 and MICA/B reversed the effects of O3-exposed NECs on IFN-γ production in NK cells. Taken together, these data showed that interactions between NECs and NK cells in the context of O3 exposure changes NK cell activity via direct cell-cell interactions and is dependent on ULBP3/MICA/B expressed on NECs. PMID:23241529

  10. Optical performance of exposed solar cell covers

    NASA Astrophysics Data System (ADS)

    Allen, Thomas H.; Hichwa, Bryant P.; Selee, Steven R.; Dodds, Jerry; Long, Greg S.

    1992-01-01

    This paper discusses the characterization results of samples flown on the Long Duration Exposure Facility (LDEF). These samples included both coated and uncoated fused silica and ceria glass substrates used in the manufacture of solar cell covers. The coatings comprised a single-layer magnesium fluoride antireflection coating and an all-dielectric high-reflector multilayer coating centered at 350 nm. Samples were mounted on both the leading and trailing surfaces of the LDEF for exposure to the environment of space. The optical properties of the coatings will be compared to control samples which were stored on the ground during the LDEF Mission. Results of Auger Electron Spectroscopy and Rutherford Backscatter Spectroscopy measurements made on several of the coatings will be presented to explain the effects of space on the chemical composition of the coatings.

  11. Optical performance of exposed solar cell covers

    NASA Technical Reports Server (NTRS)

    Hichwa, Bryant P.; Selee, Steven R.; Dodds, Jerry; Long, Greg S.

    1991-01-01

    The characterization results of samples flown on the Long Duration Exposure Facility (LDEF) are discussed. These samples included both coated and uncoated fused silica and ceria glass substrates used in the manufacture of solar cell covers. The coatings comprised a single-layer magnesium fluoride antireflection coating and an all-dielectric high-reflector multilayer coating centered at 350 nm. Samples were mounted on both the leading and trailing surfaces of the LDEF for exposure to the environment of space. The optical properties of the coatings will be compared to control samples which were stored on the ground during the LDEF Mission. Results of Auger Electron Spectroscopy and Rutherford Backscatter Spectroscopy measurements made on several of the coatings are presented to explain the effects of space on the chemical composition of the coatings.

  12. Modeling assemblies of biological cells exposed to electric fields.

    PubMed

    Fear, E C; Stuchly, M A

    1998-10-01

    Gap junctions are channels through the cell membrane that electrically connect the interiors of neighboring cells. Most cells are connected by gap junctions, and gaps play an important role in local intercellular communication by allowing for the exchange of certain substances between cells. Gap communication has been observed to change when cells are exposed to electromagnetic (EM) fields. In this work, we examine the behavior of cells connected by gap junctions when exposed to electric fields, in order to better understand the influence of the presence of gap junctions on cell behavior. This may provide insights into the interactions between biological cells and weak, low-frequency EM fields. Specifically, we model gaps in greater detail than is usually the case, and use the finite element method (FEM) to solve the resulting geometrically complex cell models. The responses of gap-connected cell configurations to both dc and time harmonic fields are investigated and compared with those of similarly shaped (equivalent) cells. To further assess the influence of the gap junctions, properties such as gap size, shape, and conductivity are varied. Our findings indicate that simple models, such as equivalent cells, are sufficient for describing the behavior of small gap-connected cell configurations exposed to dc electric fields. With larger configurations, some adjustments to the simple models are necessary to account for the presence of the gaps. The gap junctions complicate the frequency behavior of gap-connected cell assemblies. An equivalent cell exhibits low-pass behavior. Gaps effectively add a bandstop filter in series with the low-pass behavior, thus lowering the relaxation frequency. The characteristics of this bandstop filter change with changes to gap properties. Comparison of the FEM results to those obtained with simple models indicates that more complex models are required to represent gap-connected cells.

  13. T-cell homeostasis in mice exposed to airborne xenobiotics

    PubMed Central

    Drela, Nadzieja; Bień, Justyna; Kozłowska, Ewa

    2005-01-01

    Many effects of environmental toxic agents contribute to the deregulation of immune system homeostasis. Here we demonstrate that the effect of airborne suspended matter (ASM) on the generation of mouse T cells is reversible. This reversal can be achieved by an active process that returns the T cells to homeostasis and does not result from the simple effect of ASM deprivation. An accelerated development of thymocytes and increased influx of T-cell progenitors to the thymus in mice exposed to environmental xenobiotics has been postulated. This hypothesis has been confirmed by parallel increases in the percentages of single-positive and triple-negative thymocytes. Enhanced expression of thymocyte surface markers related to positive selection has also been observed. The pathway of T-cell progenitor development is favoured in the bone marrow of mice exposed to ASM. PMID:15804284

  14. Functions of TGF-β-exposed plasmacytoid dendritic cells.

    PubMed

    Saas, Philippe; Perruche, Sylvain

    2012-01-01

    Plasmacytoid dendritic cells (pDCs) belong to the family of dendritic cells and possess specific features that distinguish them from conventional dendritic cells. For instance, pDC are the main interferon-alpha-secreting cells. Plasmacytoid dendritic cells exert both proinflammatory and regulatory functions. This is attested by the involvement of pDC through interferon-alpha secretion in several autoimmune diseases, and by the implication of pDC in tolerance. The same is true for TGF-β that plays a dual role in inflammation. In this review, we discuss recent data on pDC and TGF-β interactions. As with many cell types, pDCs are able to respond to TGF-β using the classic Smad signaling pathway. In addition, pDCs are capable to secrete TGF-β, in particular in response to TGF-β exposure. Exposure of pDCs to TGF-β prevents type I interferon secretion in response to TLR7/9 ligands. In contrast, the consequences of TGF-β on the antigen-presenting cell capacities of pDC are less clear, since TGF-β-exposed pDCs may lead to both regulatory T-cell and interleukin-17-secreting cell polarization. Here, we discuss the factors that may influence this polarization. We also discuss how pDCs exposed to TGF-β may participate in tolerance induction and maintenance, or, on the contrary, in autoimmune diseases.

  15. Potassium ion fluxes in corneal epithelial cells exposed to UVB

    PubMed Central

    Ubels, John L.; Van Dyken, Rachel E.; Louters, Julienne R.; Schotanus, Mark P.; Haarsma, Loren D.

    2011-01-01

    The goal of this study was to investigate the efflux of K+ from human corneal limbal epithelial cells (HCLE) exposed to ambient levels of UVB, which is known to cause apoptosis, and to examine the effect of K+ channel blockers on loss of potassium induced by UVB. HCLE cells were exposed to 100–200 mJ/cm2 UVB, followed by incubation in culture media with 5.5 – 100 mM K+, BDS-1, Ba2+ or ouabain. To measure intracellular cations, cells were washed in 280 mM sucrose and lysed in DI water. K+ and Na+ levels in lysates were measured by ion chromatography. HCLE cells showed maximal loss of [K+]i 10 minutes after exposure to UVB and 5.5 mM K+ media, with recovery of normal K+ levels after 90 minutes. Treatment with 1 µM BDS-1 following UVB exposure reduced the loss of [K+]i retained by HCLE cells. Exposure to 0.1–5 mM Ba2+ inhibited UVB-induced K+ loss in a time and dose dependent manner. These results confirm that blocking K+ channels in HCLE cells exposed to UVB prevents efflux of K+, confirming that UVB activates K+ channels in these cells. Electrophysiology data shows that K+ channels remain highly active at least 90 minutes after UVB exposure. HCLE cells exposed to UVB and incubated 0.01–1µM ouabain did not recover from UVB-induced K+ loss. These data suggest that the Na/K pump may act to restore [K+]i to control levels in HCLE cells following UVB exposure and that the pump is not damaged by exposure to UVB. Incubation of HCLE cells exposed to UVB in medium with 25–100mM K+ media prevented K+ efflux at extracellular concentrations as low as 25mM (the concentration in tear fluid), maintaining control levels of [K+]i. In all experiments inward fluxes and intracelluar Na+ levels mirrored K+ changes, albeit at the expected lower concentrations. The prevention of UVB-induced K+i loss by 25 mM K+o is consistent with the possible contribution of the relatively high K+ concentration in tears to protection of the corneal epithelium from ambient UVB. PMID:21377460

  16. Mammalian cells exposed to ionizing radiation: Structural and biochemical aspects.

    PubMed

    Sabanero, Myrna; Azorín-Vega, Juan Carlos; Flores-Villavicencio, Lérida Liss; Castruita-Dominguez, J Pedro; Vallejo, Miguel Angel; Barbosa-Sabanero, Gloria; Cordova-Fraga, Teodoro; Sosa-Aquino, Modesto

    2016-02-01

    Acute or chronic exposure to ionizing radiation is a factor that may be hazardous to health. It has been reported that exposure to low doses of radiation (less than 50 mSv/year) and subsequently exposure to high doses produces greater effects in people. It has been reported that people who have been exposed to low doses of radiation (less than 50 mSv/year) and subsequently are exposed to high doses, have greater effects. However, at a molecular and biochemical level, it is an unknown alteration. This study, analyzes the susceptibility of a biological system (HeLa ATCC CCL-2 human cervix cancer cell line) to ionizing radiation (6 and 60 mSv/90 s). Our research considers multiple variables such as: total protein profile, mitochondrial metabolic activity (XTT assay), cell viability (Trypan blue exclusion assay), cytoskeleton (actin microfilaments), nuclei (DAPI), and genomic DNA. The results indicate, that cells exposed to ionizing radiation show structural alterations in nuclear phenotype and aneuploidy, further disruption in the tight junctions and consequently on the distribution of actin microfilaments. Similar alterations were observed in cells treated with a genotoxic agent (200 μM H2O2/1h). In conclusion, this multi-criteria assessment enables precise comparisons of the effects of radiation between various line cells. However, it is necessary to determine stress markers for integration of the effects of ionizing radiation.

  17. Comparative genomic hybridization study of arsenic-exposed and non-arsenic-exposed urinary transitional cell carcinoma

    SciTech Connect

    Hsu, L.-I; Chiu, Allen W.; Pu, Y.-S.; Wang, Y.-H.; Huan, Steven K.; Hsiao, C.-H.; Hsieh, F.-I; Chen, C.-J.

    2008-03-01

    To compare the differences in DNA aberrations between arsenic-exposed and non-arsenic-exposed transitional cell carcinoma (TCC), we analyzed 19 arsenic-exposed and 29 non-arsenic-exposed urinary TCCs from Chi-Mei Hospital using comparative genomic hybridization. DNA aberrations were detected in 42 TCCs including 19 arsenic-exposed and 23 non-arsenic-exposed TCCs. Arsenic-exposed TCCs had more changes than unexposed TCCs (mean {+-} SD, 6.6 {+-} 2.9 vs. 2.9 {+-} 2.2). Arsenic exposure was significantly associated with the number of DNA aberrations after adjustment for tumor stage, tumor grade and cigarette smoking in multiple regression analysis. The most frequent DNA gains, which were strikingly different between arsenic-exposed and non-arsenic-exposed TCCs, included those at 1p, 4p, 4q and 8q. A much higher frequency of DNA losses in arsenic-exposed TCCs compared with non-arsenic-exposed TCCs was observed in 10q, 11p and 17p. Chromosomal loss in 17p13 was associated not only with arsenic exposure, but also with tumor stage and grade. The p53 immunohistochemistry staining showed that chromosome 17p13 loss was associated with either p53 no expression (25%) or p53 overexpression (75%). The findings suggest that long-term arsenic exposure may increase the chromosome abnormality in TCC, and 17p loss plays an important role in arsenic-induced urinary carcinogenesis.

  18. Chromosome aberrations in ataxia telangiectasia cells exposed to heavy ions

    NASA Astrophysics Data System (ADS)

    Kawata, T.; Cucinotta, F.; George, K.; Wu, H.; Shigematsu, N.; Furusawa, Y.; Uno, T.; Isobe, K.; Ito, H.

    Understanding of biological effects of heavy ions is important to assess healt h risk in space. One of the most important issues may be to take into account individual susceptibility. Ataxia telangiectasia (A-T) cells are known to exhibit abnormal responses to radiations but the mechanism of hyper radiosensitivity of A-T still remains unknown. We report chromosome aberrations in normal human fibroblasts and AT fibroblasts exposed to low- and high-LET radiations. A chemical-induced premature chromosome condensation (PCC) technique combined with chromosome- painting technique was applied to score chromosome aberrations in G2/M-phase cells. Following gamma irradiation, GM02052 cells were approximately 5 times more sensitive to g-rays than AG1522 cells. GM02052 cells had a much higher frequency of deletions and misrejoining than AG1522 cells. When the frequency of complex type aberrations was compared, GM02052 cells showed more than 10 times higher frequency than AG1522 cells. The results will be compared with those obtained from high-LET irradiations.

  19. The efficiency of photovoltaic cells exposed to pulsed laser light

    NASA Technical Reports Server (NTRS)

    Lowe, R. A.; Landis, G. A.; Jenkins, P.

    1993-01-01

    Future space missions may use laser power beaming systems with a free electron laser (FEL) to transmit light to a photovoltaic array receiver. To investigate the efficiency of solar cells with pulsed laser light, several types of GaAs, Si, CuInSe2, and GaSb cells were tested with the simulated pulse format of the induction and radio frequency (RF) FEL. The induction pulse format was simulated with an 800-watt average power copper vapor laser and the RF format with a frequency-doubled mode-locked Nd:YAG laser. Averaged current vs bias voltage measurements for each cell were taken at various optical power levels and the efficiency measured at the maximum power point. Experimental results show that the conversion efficiency for the cells tested is highly dependent on cell minority carrier lifetime, the width and frequency of the pulses, load impedance, and the average incident power. Three main effects were found to decrease the efficiency of solar cells exposed to simulated FEL illumination: cell series resistance, LC 'ringing', and output inductance. Improvements in efficiency were achieved by modifying the frequency response of the cell to match the spectral energy content of the laser pulse with external passive components.

  20. Cloning assay thresholds on cells exposed to ultrafast laser pulses

    NASA Astrophysics Data System (ADS)

    Koenig, Karsten; Riemann, Iris; Fischer, Peter; Becker, Thomas P.; Oehring, Hartmut; Halbhuber, Karl-Juergen

    1999-06-01

    The influence of the peak power, laser wavelength and the pulse duration of near infrared (NIR) ultrashort laser pulses on the reproduction behavior of Chinese hamster ovary (CHO) cells has been studied. In particular we determined the cloning efficiency of single cell pairs after exposure to ultrashort laser pulses with an intensity in the range of GW/cm2 and TW/cm2. A total of more than 3500 non- labeled cells were exposed to a highly focused scanning beam of a multiphoton laser microscope with 60 microsecond pixel dwell time per scan. The beam was provided by a tunable argon ion laser pumped mode-locked 76 MHz Titanium:Sapphire laser as well as by a compact solid-state laser based system (Vitesse) at a fixed wavelength of 800 nm. Pulse duration (tau) was varied in the range of 100 fs to 4 ps by out-of-cavity pulse- stretching units consisting of SF14 prisms and blazed gratings. Within an optical (laser power) window CHO cells could be scanned for hours without severe impact on reproduction behavior, morphology and vitality. Ultrastructural studies reveal that mitochondria are the major targets of intense destructive laser pulses. Above certain laser power P thresholds, CHO cells started to delay or failed to undergo cell division and, in part, to develop uncontrolled cell growth (giant cell formation). The damage followed a P2/(tau) relation which is typical for a two-photon excitation process. Therefore, cell damage was found to be more pronounced at shorter pulses. Due to the same P2/(tau) relation for the efficiency of fluorescence excitation, two- photon microscopy of living cells does not require extremely short femtosecond laser pulses nor pulse compression units. Picosecond as well as femtosecond layers can be used as efficient light sources in safe two photon fluorescence microscopy. Only in three photon fluorescence microscopy, femtosecond laser pulses are advantageous over picosecond pulses.

  1. Cloning assay thresholds on cells exposed to ultrafast laser pulses

    NASA Astrophysics Data System (ADS)

    Koenig, Karsten; Riemann, Iris; Fischer, Peter; Becker, Thomas P.; Oehring, Hartmut; Halbhuber, Karl-Juergen

    1999-06-01

    The influence of the peak power, laser wavelength and the pulse duration of near infrared ultrashort laser pulses on the reproduction behavior of Chinese hamster ovary (CHO) cells has been studied. In particular, we determined the cloning efficiency of single cell pairs after exposure to ultrashort laser pulses with an intensity in the range of GW/cm2 and TW/cm2. A total of more than 3500 non- labeled cells were exposed to a highly focused scanning beam of a multiphoton laser microscope with 60 microsecond(s) pixel dwell time per scan. The beam was provided by a tunable argon ion laser pumped mode-locked 76 MHz Titanium:Sapphire laser as well as by a compact solid-state laser based system (Vitesse) at a fixed wavelength of 800 nm. Pulse duration (tau) was varied in the range of 100 fs to 4 ps by out-of- cavity pulse-stretching units consisting of SF14 prisms and blazed gratings. Within an optical (laser power) window CHO cells could be scanned for hours without severe impact on reproduction behavior, morphology and vitality. Ultrastructural studies reveal that mitochondria are the major targets of intense destructive laser pulses. Above certain laser power P thresholds, CHO cells started to delay or failed to undergo cell division and, in part, to develop uncontrolled cell growth (giant cell formation). The damage followed a P2/(tau) relation which is typical for a two- photon excitation process. Therefore, cell damage was found to be more pronounced at shorter pulses. Due to the same P2/(tau) relation for the efficiency of fluorescence excitation, two-photon microscopy of living cells does not require extremely short femtosecond laser pulses nor pulse compression units. Picosecond as well as femtosecond lasers can be used as efficient light sources in safe two photon fluorescence microscopy. Only in three photon fluorescence microscopy, femtosecond laser pulses are advantageous over picosecond pulses.

  2. Synthesis of protein in intestinal cells exposed to cholera toxin

    SciTech Connect

    Peterson, J.W.; Berg, W.D. Jr.; Coppenhaver, D.H.

    1987-11-01

    The mechanism by which cyclic adenosine monophosphate (AMP), formed by intestinal epithelial cells in response to cholera toxin, ultimately results in alterations in water and electrolyte transport is poorly understood. Several studies have indicated that inhibitors of transcription or translation block much of the transport of ions and water in the intestine and edema formation in tissue elicited by cholera toxin. Data presented in this study confirmed the inhibitory effects of cycloheximide on cholera toxin-induced fluid accumulation in the rabbit intestinal loop model. Neither cycloheximide nor actinomycin D altered the amount of cyclic AMP that accumulated in intestinal cells and Chinese hamster ovary cells exposed to cholera toxin. An increase in (/sup 3/H) leucine incorporation was readily demonstrable in intestinal epithelial cells from rabbits challenged with Vibrio cholerae. Similarly, intestinal epithelial cells incubated with cholera toxin for 4 hr synthesized substantially more protein than controls as determined by relative incorporation of (/sup 35/S) methionine. Most of the new protein synthesized in response to cholera toxin was membrane associated and of high molecular weight. The possible significance of the toxin-induced protein relative to cholera pathogenesis was discussed.

  3. Polyamines and polyamine biosynthesis in cells exposed to hyperthermia

    SciTech Connect

    Gerner, E.W.; Stickney, D.G.; Herman, T.S.; Fuller, D.J.

    1983-02-01

    The issue of how polyamines act to sensitize cultured cells to the lethal effects of hyperthermia was investigated using Chinese hamster cells which were induced to express thermotolerance. Intracellular levels of these naturally occurring polycations were manipulated in certain situations by treating whole cells with methylglyoxal bis-(guanylhydrazone), an inhibitor of the S-adenosyl-L-methionine decarboxylases. Exogenous spermine as low as 100 ..mu..M in the culture media dramatically sensitized cells expressing thermotolerance to the lethal effects of subsequent 42/sup 0/C exposures. When thermotolerance was differentially induced in cultures exposed to 42.4/sup 0/C by varying the rate of heating from 37 to 42.4/sup 0/C, the most resistant cells and the highest levels of intracellular spermidine and spermine. This finding was explainable in part by the observation that the putrescine-dependent S-adenosyl-L-methionine decarboxylase activity was minimally affected in cells expressng the greatest degree of thermotolerance. When this enzyme activity was inhibited by drug, lowered intracellular polyamine levels did not correspond with subsequent survival responses to heat. Interestingly, cultures treated with methylglyoxal bis-(guanylhydrazone) 24 hr previous to heat exposure showed a reduced capacity to express rate of heating-induced thermotolerance. Together, these results demonstrate that the polyamines, especially spermidine and spermine, enhance hyperthermia-induced cell killing by some mechanism involving the plasma membrane. Further, our data suggest that methylglyoxal bis-(guanylhydrazone) can act to affect thermal responses by a mechanism(s) other than modification of intracellular polyamine levels.

  4. Expression of functionally relevant cell surface markers in dibutyltin-exposed human natural killer cells.

    PubMed

    Odman-Ghazi, Sabah O; Hatcher, Frank; Whalen, Margaret M

    2003-07-25

    Butyltin (BT) compounds are known for their worldwide contamination. Dibutyltin (DBT) is used as a stabilizer in plastic products, and as a deworming agent in poultry. Poultry products have been shown to contain measurable levels of DBT. Drinking water has also been reported to contain BTs due to leaching from PVC pipes. We, and others, have found measurable levels of DBT in human blood. BTs appear to increase the risk of cancer and other viral infections in exposed individuals. In previous studies we have shown that the tumor killing function of natural killer (NK) lymphocytes was greatly diminished after as little as a 1 h exposure to DBT and the inhibition continued even after removal of the compound. We also showed that there was a significant decrease in NK cell lysis of K562 target cells after an exposure to 1.5 microM DBT for 24 h. This 24 h exposure also decreased the ability of NK cells to bind to tumor cells. Loss of binding function was not seen when NK cells were exposed to 5-10 microM DBT for 1 h. However, NK cells exposed to 5 microM DBT for 1 h and then incubated in DBT-free media for 24, 48, or 96 h, showed a significant loss of tumor-binding function within 24 h. The effects of DBT exposure on seven cell surface molecules that are involved in NK-cell interactions with target cells were investigated. The results indicated that the exposure of NK cells to 1.5 microM DBT for 24 h decreased the expression of CD2, CD11a, CD16, CD11c. There was no decrease in expression of any of the markers studied when NK cells were exposed to 5 microM DBT for 1 h, consistent with the fact that a 1-h exposure had no effect on the ability of NK cells to bind tumor cells. However, when NK cells were exposed to 5 microM DBT for 1 h followed by 24, 48 or 96 h incubations in DBT-free media there was decreased expression of several of the cells surface molecules with the most dramatic decreases being in CD16 and CD56.

  5. Cell death pathways in directly irradiated cells and cells exposed to medium from irradiated cells.

    PubMed

    Jella, Kishore Kumar; Garcia, Amaya; McClean, Brendan; Byrne, Hugh J; Lyng, Fiona M

    2013-03-01

    The aim of this study was to compare levels of apoptosis, necrosis, mitotic cell death and senescence after treatment with both direct radiation and irradiated cell conditioned medium. Human keratinocytes (HaCaT cell line) were irradiated (0.005, 0.05 and 0.5 Gy) using a cobalt 60 teletherapy unit. For bystander experiments, the medium was harvested from donor HaCaT cells 1 hour after irradiation and transferred to recipient HaCaT cells. Clonogenic assay, apoptosis, necrosis, mitotic cell death, senescence and cell cycle analysis were measured in both directly irradiated cells and bystander cells A reduction in cell survival was observed for both directly irradiated cells and irradiated cell conditioned medium (ICCM)-treated cells. Early apoptosis and necrosis was observed predominantly after direct irradiation. An increase in the number of cells in G2/M phase was observed at 6 and 12 h which led to mitotic cell death after 72 h following direct irradiation and ICCM treatment. No senescence was observed in the HaCaT cell line following either direct irradiation or treatment with ICCM. This study has shown that directly irradiated cells undergo apoptosis, necrosis and mitotic cell death whereas ICCM-treated cells predominantly undergo mitotic cell death.

  6. Impaired NK Cell Activation and Chemotaxis toward Dendritic Cells Exposed to Complement-Opsonized HIV-1.

    PubMed

    Ellegård, Rada; Crisci, Elisa; Andersson, Jonas; Shankar, Esaki M; Nyström, Sofia; Hinkula, Jorma; Larsson, Marie

    2015-08-15

    Mucosa resident dendritic cells (DCs) may represent one of the first immune cells that HIV-1 encounters during sexual transmission. The virions in body fluids can be opsonized with complement factors because of HIV-mediated triggering of the complement cascade, and this appears to influence numerous aspects of the immune defense targeting the virus. One key attribute of host defense is the ability to attract immune cells to the site of infection. In this study, we investigated whether the opsonization of HIV with complement (C-HIV) or a mixture of complement and Abs (CI-HIV) affected the cytokine and chemokine responses generated by DCs, as well as their ability to attract other immune cells. We found that the expression levels of CXCL8, CXCL10, CCL3, and CCL17 were lowered after exposure to either C-HIV or CI-HIV relative to free HIV (F-HIV). DCs exposed to F-HIV induced higher cell migration, consisting mainly of NK cells, compared with opsonized virus, and the chemotaxis of NK cells was dependent on CCL3 and CXCL10. NK cell exposure to supernatants derived from HIV-exposed DCs showed that F-HIV induced phenotypic activation (e.g., increased levels of TIM3, CD69, and CD25) and effector function (e.g., production of IFNγ and killing of target cells) in NK cells, whereas C-HIV and CI-HIV did not. The impairment of NK cell recruitment by DCs exposed to complement-opsonized HIV and the lack of NK activation may contribute to the failure of innate immune responses to control HIV at the site of initial mucosa infection.

  7. Na(+)/K(+)-ATPase immunoreactivity in branchial chloride cells of Oreochromis mossambicus exposed to copper.

    PubMed

    Dang, Z; Lock, R A; Flik, G; Wendelaar Bonga, S E

    2000-01-01

    Chloride cells were identified by Na(+)/K(+)-ATPase immunocytochemistry at the light and electron microscope levels in gills of freshwater tilapia Oreochromis mossambicus. Turnover of chloride cells was enhanced by exposing the fish to waterborne copper (3.2 micromol l(-)(1)) for 14 days, as indicated by a 38 % increase in cells expressing proliferating cell nuclear antigen (PCNA) relative to controls. The expression of PCNA was most marked in the central area of the filamental epithelium, from where the chloride cells are thought to originate and migrate. In control fish, chloride cells were associated exclusively with the filamental epithelium. In both controls and copper-exposed fish, two chloride cell populations were seen after Na(+)/K(+)-ATPase immunostaining. These probably represent subpopulations of newly emerged chloride cells: (1) strongly stained cells (mature chloride cells) in the filamental and lamellar epithelium and (2) weakly stained cells, identified by electron microscopy as apoptotic and necrotic chloride cells, mainly in the filamental epithelium. Absolute numbers of mature chloride cells fell, while necrotic and apoptotic chloride cell numbers increased, in copper-exposed fish. A strong correlation could be established for gill Na(+)/K(+)-ATPase specific activity and the number of strongly stained chloride cells in controls and copper-exposed fish and for Na(+)/K(+)-ATPase specific activity and total numbers of immunoreactive cells in copper-exposed fish owing to an increased incidence of weakly staining cells.

  8. Detection of programmed cell death in cells exposed to genotoxic agents using a caspase activation assay.

    PubMed

    Gupta, Madhu; Santra, Madhumita; Koty, Patrick P

    2014-01-01

    Many toxins that individuals are exposed to cause DNA damage. Cells that have sustained DNA damage may attempt to repair the damage prior to replication. However, if a cell has sustained serious damage it cannot repair, it will commit suicide through a genetically regulated programmed cell death (PCD) pathway. Crucial to the ultimate execution of PCD is a family of cysteine proteases called caspases. Activation of these enzymes occurs late enough in the PCD pathway that a cell can no longer avoid cell death, but still earlier than PCD-associated morphological changes or DNA fragmentation. This protocol details a method for using fluorochrome-conjugated caspase inhibitors for the detection of activated caspases in intact cells. The analysis and documentation is performed using fluorescence microscopy.

  9. Cytoplasmic myosin exposed apoptotic cells appear with caspase-3 activation and enhance CLL cell viability

    PubMed Central

    Cui, Xiaoxuan; Zhang, Lu; Magli, Amanda R.; Catera, Rosa; Yan, Xiao-Jie; Griffin, Daniel O.; Rothstein, Thomas L.; Barrientos, Jacqueline; Kolitz, Jonathan E.; Allen, Steven L.; Rai, Kanti R.; Chiorazzi, Nicholas; Chu, Charles C.

    2015-01-01

    The degree of chronic lymphocytic leukemia (CLL) B-cell antigen receptor (BCR) binding to myosin exposed apoptotic cells (MEACs) correlates with worse patient outcomes, suggesting a link to disease activity. Therefore, we studied MEAC formation and the effects of MEAC binding on CLL cells. In cell line studies, both intrinsic (spontaneous or camptothecin-induced) and extrinsic (FasL- or anti-Fas-induced) apoptosis created a high percent of MEACs over time in a process associated with caspase-3 activation, leading to cytoplasmic myosin cleavage and trafficking to cell membranes. The involvement of common apoptosis pathways suggests that most cells can produce MEACs and indeed CLL cells themselves form MEACs. Consistent with the idea that MEAC formation may be a signal to remove dying cells, we found that natural IgM antibodies bind to MEACs. Functionally, co-culture of MEACs with CLL cells, regardless of immunoglobulin heavy chain variable region gene mutation status, improved leukemic cell viability. Based on inhibitor studies, this improved viability involved BCR signaling molecules. These results support the hypothesis that stimulation of CLL cells with antigen, such as those on MEACs, promotes CLL cell viability, which in turn could lead to progression to worse disease. PMID:26220042

  10. The proliferative effects of asbestos-exposed peripheral blood mononuclear cells on mesothelial cells

    PubMed Central

    MAKI, YUHO; NISHIMURA, YASUMITSU; TOYOOKA, SHINICHI; SOH, JUNICHI; TSUKUDA, KAZUNORI; SHIEN, KAZUHIKO; FURUKAWA, MASASHI; MURAOKA, TAKAYUKI; UENO, TSUYOSHI; TANAKA, NORIMITSU; YAMAMOTO, HIROMASA; ASANO, HIROAKI; MAEDA, MEGUMI; KUMAGAI-TAKEI, NAOKO; LEE, SUNI; MATSUZAKI, HIDENORI; OTSUKI, TAKEMI; MIYOSHI, SHINICHIRO

    2016-01-01

    Malignant mesothelioma (MM) is thought to arise from the direct effect of asbestos on mesothelial cells. However, MM takes a long time to develop following exposure to asbestos, which suggests that the effects of asbestos are complex. The present study examined the effects of asbestos exposure on the cell growth of MeT-5A human mesothelial cells via cytokines produced by immune cells. Peripheral blood mononuclear cells (PBMCs) were stimulated with antibodies against cluster of differentiation (CD)3 and CD28 upon exposure to the asbestos chrysotile A (CA) or crocidolite (CR); the growth of MeT-5A cells in media supplemented with PBMC culture supernatants was subsequently examined. MeT-5A cells exhibited an increase in proliferation when grown in supernatant from the 7-day PBMC culture exposed to CA or CR. Analysis of cytokine production demonstrated increased levels of granulocyte colony-stimulating factor (G-CSF), granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin (IL)-1α, IL-1β, IL-3, IL-5, IL-13 and IL-17A in supernatants. Individual administration of these cytokines, excluding G-CSF and GM-CSF, led to an increase in cell growth of MeT-5A, whereas this effect was not observed following the combined administration of these cytokines. The results indicate that cytokines secreted by immune cells upon exposure to asbestos cause an increase in the growth activity of mesothelial cells, suggesting that alterations in the production of cytokines by immune cells may contribute to tumorigenesis in individuals exposed to asbestos. PMID:27123108

  11. Genomic Variability within an Organism Exposes Its Cell Lineage Tree

    PubMed Central

    Kaplan, Shai; Feige, Uriel; Shapiro, Ehud

    2005-01-01

    What is the lineage relation among the cells of an organism? The answer is sought by developmental biology, immunology, stem cell research, brain research, and cancer research, yet complete cell lineage trees have been reconstructed only for simple organisms such as Caenorhabditis elegans. We discovered that somatic mutations accumulated during normal development of a higher organism implicitly encode its entire cell lineage tree with very high precision. Our mathematical analysis of known mutation rates in microsatellites (MSs) shows that the entire cell lineage tree of a human embryo, or a mouse, in which no cell is a descendent of more than 40 divisions, can be reconstructed from information on somatic MS mutations alone with no errors, with probability greater than 99.95%. Analyzing all ~1.5 million MSs of each cell of an organism may not be practical at present, but we also show that in a genetically unstable organism, analyzing only a few hundred MSs may suffice to reconstruct portions of its cell lineage tree. We demonstrate the utility of the approach by reconstructing cell lineage trees from DNA samples of a human cell line displaying MS instability. Our discovery and its associated procedure, which we have automated, may point the way to a future “Human Cell Lineage Project” that would aim to resolve fundamental open questions in biology and medicine by reconstructing ever larger portions of the human cell lineage tree. PMID:16261192

  12. Mesodesma mactroides Gill Cells Exposed to Copper: Does Hyposmotic Saline Increase Cytotoxicity or Cellular Defenses?

    PubMed

    Anjos, V A; Galvão, J S; Santos, V R S; Souza, M M

    2016-11-01

    Gill cells of filter feeding mollusks have cellular defense mechanisms, such as multixenobiotic resistance (MXR), that allow them to extrude possible contaminants. To analyze the cytotoxicity and cellular defenses of gills in the clam Mesodesma mactroides, gill cells were exposed to copper in both iso- and hyposmotic solutions. Analysis of MXR activity by fluorescence microscopy showed that hyposmotic saline activated defenses, whereas the presence of copper in isosmotic solution inhibited the activation of defenses. Cell viability was decreased in cells exposed to copper in isosmotic saline, but not in cells exposed to hyposmotic saline. We conclude that when cells cannot defend themselves due to decreased MXR, cell death occurs. In addition, gill cells under hyposmotic conditions have a greater capacity for defense and a lower rate of cellular mortality than when they are maintained under isosmotic conditions.

  13. Stochastic models for cells exposed to ionizing radiation

    SciTech Connect

    Yang, G.L.; Swenberg, C.E.

    1986-01-01

    The stochastic model for survivability of cells subjected to ionizing radiation initially formulated by Neyman and Puri is modified to include both the plating time to cell proliferation and dose saturation of potential lethal damage. This necessitates a reformulation of the cell survival and mutation probability. Based on the new model the authors derive the the probability of occurrence for several experimental end points. The predictions of the model compare favorably to data for diploid yeast cells irradiated with 30-MeV electrons.

  14. Changes in morphology, cell wall composition and soluble proteome in Rhodobacter sphaeroides cells exposed to chromate.

    PubMed

    Italiano, Francesca; Rinalducci, Sara; Agostiano, Angela; Zolla, Lello; De Leo, Francesca; Ceci, Luigi R; Trotta, Massimo

    2012-10-01

    The response of the carotenoidless Rhodobacter sphaeroides mutant R26 to chromate stress under photosynthetic conditions is investigated by biochemical and spectroscopic measurements, proteomic analysis and cell imaging. Cell cultures were found able to reduce chromate within 3-4 days. Chromate induces marked changes in the cellular dimension and morphology, as revealed by atomic force microscopy, along with compositional changes in the cell wall revealed by infrared spectroscopy. These effects are accompanied by significant changes in the level of several proteins: 15 proteins were found up-regulated and 15 down-regulated. The protein content found in chromate exposed cells is in good agreement with the biochemical, spectroscopic and microscopic results. Moreover at the present stage no specific chromate-reductase could be found in the soluble proteome, indicating that detoxification of the pollutant proceeds via aspecific reductants.

  15. In vitro action of sho-seiryu-to on allergen-exposed mononuclear cells.

    PubMed

    Tanaka, M; Inoue, K; Kitamura, Y; Shimada, A; Takano, H

    2014-01-01

    Although Sho-seiryu-to (SST), used as a traditional herbal (Kampo) medicine mainly in China and Korea, is shown to have immunomodulating potential, such as an anti-allergic one, its underlying mechanism has not been completely clarified. To partially address the issue, we explored its effects on allergen-exposed mononuclear cells. Male balb/c mice were intraperitoneally administered ovalbumin (OVA: 20 μg) plus alum or vehicle twice (Day 0 and Day 14). At Day 21, mice were sacrificed and splenocytes (mononuclear cells) were isolated and cultured in the presence or absence of OVA with or without SST. Thereafter, helper T-related cytokines in the culture supernatants were evaluated by means of ELISA. Protein level of interferon-γ was lower than 5.0 pg/mL in the supernatants from OVA– non-exposed or -exposed mononuclear cells in the presence or absence of OVA stimulation. On the other hand, SST induced the cytokine from both types of mononuclear cells in the presence (P < 0.05) or absence of OVA stimulation as compared to corresponding control. By contrast, interleukin (IL)-4 level tended to be decreased by SST in OVA-non-exposed mononuclear cells as did IL-13 in both non-exposed and exposed mononuclear cells as compared to vehicle. In conclusion, immunoregulating efficacy by SST on allergy-prone subjects may include, at least in part, restoring helper T balance mainly through hyperproduction of IFN-γ against mononuclear cells such as lymphocytes.

  16. [Apoptosis of pulmonary epithelial cells and endothelial cells in mice exposed to phosgene].

    PubMed

    Li, Wen-li; Hai, Chun-xu; Yang, Chen; Li, Bo; Liu, Rui; Zhang, Xiao-di

    2005-08-01

    To study apoptosis of pulmonary epithelial cells and endothelial cells in mice with pulmonary edema induced by phosgene exposure. Thirty-two mice were divided into normal group and phosgene group with 16 mice in each group. The mice in phosgene group were exposed to phosgene (11.9 mg/L) for 5 min and those in the control group to air. Four hours after exposure, alveolar type II cells were isolated and cultured to observe their apoptosis by electron microscope and flow cytometry. The lung tissues were also taken for DNA gel electrophoresis and TUNEL assay. Apoptotic bodies were observed in alveolar type II cells under electron microscope in phosgene group, which had higher cell apoptosis rate than the control group [(40.26+/-7.74)% vs (1.58+/-1.01)%, P<0.001] as determined by flow cytometry. Ladder-like DNA fragmentation pattern was observed in DNA gel electrophoresis in phosgene group with apoptosis of the pulmonary epithelial and endothelial cells observed by TUNEL. Phosgene can induce pulmonary epithelial and endothelial cell apoptosis in mice, suggesting that the mechanism of phosgene-induced pulmonary edema involves apoptosis of the lung cells.

  17. Reduced activation and proliferation of human lymphocytes exposed to respiratory syncytial virus compared to cells exposed to influenza virus.

    PubMed

    Fleming, Elisa H; Ochoa, Eliana E; Nichols, Joan E; O'Banion, M Kerry; Salkind, Alan R; Roberts, Norbert J

    2017-08-30

    Both respiratory syncytial virus (RSV) and influenza A virus (IAV) may infect human peripheral blood mononuclear leukocytes (PBMC) during the immune response to viral challenge as the cells are recruited to the respiratory tract. The current studies demonstrated differences in PBMC responses to the two viruses very early after exposure, including reduced fos protein and CD69 expression and IL-2 production by RSV-exposed T lymphocytes. Exposure to RSV resulted in reduced lymphocyte proliferation despite evidence of a virus-specific T lymphocyte frequency equivalent to that for influenza virus. Reduced RSV-induced proliferation was not due to apoptosis, which was itself reduced relative to that of influenza virus-exposed T lymphocytes. The data indicate that differential immune responses to RSV and influenza virus are determined early after exposure of human PBMC and support the concept that the anamnestic immune response that might prevent clinically evident reinfection is attenuated very soon after exposure to RSV. Thus, candidate RSV vaccines should be expected to reduce but not prevent clinical illness upon subsequent infection by RSV. Furthermore, effective therapeutic agents for RSV are likely to be needed, especially for high-risk populations, even after vaccine development. © 2017 Wiley Periodicals, Inc.

  18. Mitochondrial DNA damage and oxidative damage in HL-60 cells exposed to 900MHz radiofrequency fields.

    PubMed

    Sun, Yulong; Zong, Lin; Gao, Zhen; Zhu, Shunxing; Tong, Jian; Cao, Yi

    2017-03-01

    HL-60 cells, derived from human promyelocytic leukemia, were exposed to continuous wave 900MHz radiofrequency fields (RF) at 120μW/cm(2) power intensity for 4h/day for 5 consecutive days to examine whether such exposure is capable damaging the mitochondrial DNA (mtDNA) mediated through the production of reactive oxygen species (ROS). In addition, the effect of RF exposure was examined on 8-hydroxy-2'-dexoyguanosine (8-OHdG) which is a biomarker for oxidative damage and on the mitochondrial synthesis of adenosine triphosphate (ATP) which is the energy required for cellular functions. The results indicated a significant increase in ROS and significant decreases in mitochondrial transcription factor A, mtDNA polymerase gamma, mtDNA transcripts and mtDNA copy number in RF-exposed cells compared with those in sham-exposed control cells. In addition, there was a significant increase in 8-OHdG and a significant decrease in ATP in RF-exposed cells. The response in positive control cells exposed to gamma radiation (GR, which is also known to induce ROS) was similar to those in RF-exposed cells. Thus, the overall data indicated that RF exposure was capable of inducing mtDNA damage mediated through ROS pathway which also induced oxidative damage. Prior-treatment of RF- and GR-exposed the cells with melatonin, a well-known free radical scavenger, reversed the effects observed in RF-exposed cells. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Enhanced aggressiveness of benzopyrene-induced squamous carcinomas in transgenic mice overexpressing the proprotein convertase PACE4 (PCSK6)

    PubMed Central

    Bassi, Daniel E.; Cenna, Jonathan; Zhang, Jirong; Cukierman, Edna; Klein-Szanto, Andres J.

    2014-01-01

    PACE4 (PCSK6) is a pro-protein convertase (PC) capable of processing numerous substrates involved in tumor growth, invasion, and metastasis. Because of the human relevancy of the tobacco-associated carcinogen benzo[a]pyrene (B(a)P) we investigated whether transgenic mice in which this PC is targeted to the epidermis (K5-PACE4) may be more susceptible to B(a)P complete carcinogenesis than wild type (WT) mice. In an in vitro experiment, using cell lines derived from skin tumors obtained after B(a)P treatment, we observed that PACE4 overexpression and activity accounts for an increased proliferation rate, exaggerated sensitivity to the PC inhibitor CMK, and interference with IGF-1R autophosphorylation. Squamous cell carcinomas, obtained from K5-PACE4 mice subjected to complete chemical carcinogenesis, were characterized by a 50 % increase in cell proliferation, when compared with similar tumors from WT mice. In addition, tumors from K5-PACE4 mice showed deeper invasion into the underlying dermis. Thus, mice overexpressing PACE4 exhibited tumors of increased growth rate and invasive potential when exposed to the human carcinogen B(a)P, further supporting the significance of PCs in tumor growth and progression. PMID:24845697

  20. Enhanced aggressiveness of benzopyrene-induced squamous carcinomas in transgenic mice overexpressing the proprotein convertase PACE4 (PCSK6).

    PubMed

    Bassi, Daniel E; Cenna, Jonathan; Zhang, Jirong; Cukierman, Edna; Klein-Szanto, Andres J

    2015-10-01

    PACE4 (PCSK6) is a proprotein convertase (PC) capable of processing numerous substrates involved in tumor growth, invasion, and metastasis. Because of the human relevancy of the tobacco-associated carcinogen benzo[a]pyrene (B(a)P) we investigated whether transgenic mice in which this PC is targeted to the epidermis (K5-PACE4) may be more susceptible to B(a)P complete carcinogenesis than wild type (WT) mice. In an in vitro experiment, using cell lines derived from skin tumors obtained after B(a)P treatment, we observed that PACE4 overexpression and activity accounts for an increased proliferation rate, exaggerated sensitivity to the PC inhibitor CMK, and interference with IGF-1R autophosphorylation. Squamous cell carcinomas, obtained from K5-PACE4 mice subjected to complete chemical carcinogenesis, were characterized by a 50% increase in cell proliferation, when compared with similar tumors from WT mice. In addition, tumors from K5-PACE4 mice showed deeper invasion into the underlying dermis. Thus, mice overexpressing PACE4 exhibited tumors of increased growth rate and invasive potential when exposed to the human carcinogen B(a)P, further supporting the significance of PCs in tumor growth and progression.

  1. Viscoelastic properties of vascular endothelial cells exposed to uniaxial stretch

    NASA Astrophysics Data System (ADS)

    Osterday, Kathryn; Chew, Thomas; Loury, Phillip; Haga, Jason; Del Alamo, Juan C.; Chien, Shu

    2011-11-01

    Vascular endothelial cells (VECs) line the interior of blood vessels and regulate a variety of functions in the cardiovascular system. It is widely accepted that VECs will remodel themselves in response to mechanical stimuli, but few studies have analyzed the mechanical properties of these cells under stretch. We hypothesize that uniaxial stretch will cause an anisotropic realignment of actin filaments, and a change in the viscoelastic properties of the cell. To test this hypothesis, VECs were grown on a thin, transparent membrane mounted on a microscope. The membrane was stretched, consequently stretching the cells. Time-lapse sequences of the cells were taken every hour with a time resolution of 10 Hz. The random trajectories of intracellular endogenous particles were tracked using in-house algorithms. These trajectories were analyzed using a novel particle tracking microrheology formulation that takes into account the anisotropy of the cytoplasm of VECs. Supported by NSF CBET-1055697 CAREER Award (JCA) and NIH grants BRP HL064382 (SC), 1R01 HL080518 (SC).

  2. Enhanced cellular respiration in cells exposed to doxorubicin.

    PubMed

    Souid, Abdul-Kader; Penefsky, Harvey S; Sadowitz, Peter D; Toms, Bonnie

    2006-01-01

    Doxorubicin executes topoisomerase II mediated apoptosis, a process known to result in mitochondrial dysfunction, such as the leakage of cytochrome c and the opening of mitochondrial permeability transition pores (PTP). To further define the effects of doxorubicin on cell metabolism, we measured cellular respiration, cellular ATP, DNA fragmentation, and cytochrome c leakage in Jurkat (supersensitive), human leukemia-60 (HL-60, sensitive), and HL-60/MX2 (resistant) cells following exposure to 1.0 microM doxorubicin for 30 min. The measurements were made after 24 h of exposure to the drug. In Jurkat and HL-60 cells, doxorubicin treatment increased cellular mitochondrial oxygen consumption and ATP content by 2-3-fold. The increment in oxygen consumption was blocked by the pan-caspase inhibitor benzyloxycarbonyl-Val-Ala-dl-Asp-fluoromethylketone (zVAD-fmk) and by the PTP inhibitor cyclosporin A. In HL-60/MX2 cells, which are resistant because of a reduced topoisomerase II activity, doxorubicin treatment was without effect on either respiration or ATP content, suggesting that topoisomerase II was essential for induction of apoptosis and stimulation of respiration and ATP content. The conclusion that both of the latter processes were products of oxidations in the mitochondrial respiratory chain was supported by the further observation that rotenone and sodium cyanide inhibited oxygen consumption and substantially lowered ATP content in the treated and untreated cells. Thus, oxidative phosphorylation is enhanced in cells briefly incubated with doxorubicin for as long as 24 h post drug exposure despite apoptosis-associated mitochondrial insults caused by the drug.

  3. Ultrastructural changes in tracheal epithelial cells exposed to oxygen

    NASA Technical Reports Server (NTRS)

    Philpott, D. E.; Harrison, G. A.; Turnbill, C.; Black, S.

    1977-01-01

    White albino rats were sacrificed after 24, 36, 48, 72, and 96 h of exposure to 100% O2 at 1 atm. Tissue was prepared for the scanning electron microscope (SEM) by Critical Point Drying and for the transmission electron microscope (TEM) by plastic embedding. Scanning microscopy showed a loss of microvilli after 48 h of exposure. Cilia appeared relatively normal with SEM, but TEM revealed changes in the outer membrane. In TEM, nonciliated cells appeared swollen and often encroached on the ciliated cells. A heavy mucous blanket remained even after processing. All the changes observed that are induced by oxygen exposure contribute to mucostasis, reducing and/or halting mucociliary clearance.

  4. Ultrastructural changes in tracheal epithelial cells exposed to oxygen

    NASA Technical Reports Server (NTRS)

    Philpott, D. E.; Harrison, G. A.; Turnbill, C.; Black, S.

    1977-01-01

    White albino rats were sacrificed after 24, 36, 48, 72, and 96 h of exposure to 100% O2 at 1 atm. Tissue was prepared for the scanning electron microscope (SEM) by Critical Point Drying and for the transmission electron microscope (TEM) by plastic embedding. Scanning microscopy showed a loss of microvilli after 48 h of exposure. Cilia appeared relatively normal with SEM, but TEM revealed changes in the outer membrane. In TEM, nonciliated cells appeared swollen and often encroached on the ciliated cells. A heavy mucous blanket remained even after processing. All the changes observed that are induced by oxygen exposure contribute to mucostasis, reducing and/or halting mucociliary clearance.

  5. Correlation between dielectric property by dielectrophoretic levitation and growth activity of cells exposed to electric field.

    PubMed

    Hakoda, Masaru; Hirota, Yusuke

    2013-09-01

    The purpose of this study is to develop a system analyzing cell activity by the dielectrophoresis method. Our previous studies revealed a correlation between the growth activity and dielectric property (Re[K(ω)]) of mouse hybridoma 3-2H3 cells using dielectrophoretic levitation. Furthermore, it was clarified that the differentiation activity of many stem cells could be evaluated by the Re[K(ω)] without differentiation induction. In this paper, 3-2H3 cells exposed to an alternating current (AC) electric field or a direct current (DC) electric field were cultivated, and the influence of damage by the electric field on the growth activity of the cells was examined. To evaluate the activity of the cells by measuring the Re[K(ω)], the correlation between the growth activity and the Re[K(ω)] of the cells exposed to the electric field was examined. The relations between the cell viability, growth activity, and Re[K(ω)] in the cells exposed to the AC electric field were obtained. The growth activity of the cells exposed to the AC electric field could be evaluated by the Re[K(ω)]. Furthermore, it was found that the adverse effects of the electric field on the cell viability and the growth activity were smaller in the AC electric field than the DC electric field.

  6. Autosomal mutants of proton-exposed kidney cells display frequent loss of heterozygosity on nonselected chromosomes.

    PubMed

    Grygoryev, Dmytro; Dan, Cristian; Gauny, Stacey; Eckelmann, Bradley; Ohlrich, Anna P; Connolly, Marissa; Lasarev, Michael; Grossi, Gianfranco; Kronenberg, Amy; Turker, Mitchell S

    2014-05-01

    High-energy protons found in the space environment can induce mutations and cancer, which are inextricably linked. We hypothesized that some mutants isolated from proton-exposed kidneys arose through a genome-wide incident that causes loss of heterozygosity (LOH)-generating mutations on multiple chromosomes (termed here genomic LOH). To test this hypothesis, we examined 11 pairs of nonselected chromosomes for LOH events in mutant cells isolated from the kidneys of mice exposed to 4 or 5 Gy of 1 GeV protons. The mutant kidney cells were selected for loss of expression of the chromosome 8-encoded Aprt gene. Genomic LOH events were also assessed in Aprt mutants isolated from isogenic cultured kidney epithelial cells exposed to 5 Gy of protons in vitro. Control groups were spontaneous Aprt mutants and clones isolated without selection from the proton-exposed kidneys or cultures. The in vivo results showed significant increases in genomic LOH events in the Aprt mutants from proton-exposed kidneys when compared with spontaneous Aprt mutants and when compared with nonmutant (i.e., nonselected) clones from the proton-exposed kidneys. A bias for LOH events affecting chromosome 14 was observed in the proton-induced Aprt mutants, though LOH for this chromosome did not confer increased radiation resistance. Genomic LOH events were observed in Aprt mutants isolated from proton-exposed cultured kidney cells; however the incidence was fivefold lower than in Aprt mutants isolated from exposed intact kidneys, suggesting a more permissive environment in the intact organ and/or the evolution of kidney clones prior to their isolation from the tissue. We conclude that proton exposure creates a subset of viable cells with LOH events on multiple chromosomes, that these cells form and persist in vivo, and that they can be isolated from an intact tissue by selection for a mutation on a single chromosome.

  7. Changes observed in erythrocyte cells exposed to an alternating current.

    PubMed

    Jeican, Ionut Isaia; Matei, Horea; Istrate, Alexandru; Mironescu, Eugen; Bâlici, Ştefana

    2017-01-01

    Appliance of electric pulses induces red blood cells (RBCs) membrane poration, membrane aminophospholipid perturbation and alteration of the normal flip-flop process, resulting in various shape changes of the RBCs. We studied morphological and water permeability changes of RBCs bombarded with electrons in an alternating current circuit. We used three venous blood samples of 100 mL and an alternating current device. The harvested blood was divided into four experimental sets to be used for various exposure times: 0 hours (control RBCs), 0.5h, 3h and 6h (electric-stimulated RBCs). Following the electric current each of the four sets were further divided into three samples: one for the assessment of the echinocytes/RBCs ratio, another for the electron microscopy study of ultrastructural changes induced by the alternating electrical current and a larger third one for determining water permeability of RCBs by (1)H-NMR spectroscopy and morphological measurements. There is a small but statistically significant effect of the RBC exposure to alternating electric current on cell diameters. Exposure to electric current is positively and strongly correlated with the percentage of echinocytes in a duration-dependent manner. There is a strong and statistically significant correlation between electric current exposure and permeability to water as measured by (1)H-NMR spectroscopy. Following interactions between electric current and RBC membrane, certain modifications were observed in the erythrocyte structure. We attribute the increased cell size to a higher permeability to water and a decreased tonicity. This leads to the transformation of the RBCs into echinocytes.

  8. Arginase inhibition enhances angiogenesis in endothelial cells exposed to hypoxia.

    PubMed

    Wang, Lin; Bhatta, Anil; Toque, Haroldo A; Rojas, Modesto; Yao, Lin; Xu, Zhimin; Patel, Chintan; Caldwell, Ruth B; Caldwell, R William

    2015-03-01

    Hypoxia-induced arginase elevation plays an essential role in several vascular diseases but influence of arginase on hypoxia-mediated angiogenesis is completely unknown. In this study, in vitro network formation in bovine aortic endothelial cells (BAEC) was examined after exposure to hypoxia for 24h with or without arginase inhibition. Arginase activity, protein levels of the two arginase isoforms, eNOS, and VEGF as well as production of NO and ROS were examined to determine the involvement of arginase in hypoxia-mediated angiogenesis. Hypoxia elevated arginase activity and arginase 2 expression but reduced active p-eNOS(Ser1177) and NO levels in BAEC. In addition, both VEGF protein levels and endothelial elongation and network formation were reduced with continued hypoxia, whereas ROS levels increased and NO levels decreased. Arginase inhibition limited ROS, restored NO formation and VEGF expression, and prevented the reduction of angiogenesis. These results suggest a fundamental role of arginase activity in regulating angiogenic function.

  9. DNA Fragmentation in mammalian cells exposed to various light ions

    NASA Astrophysics Data System (ADS)

    Belli, M.; Cherubini, R.; Dalla Vecchia, M.; Dini, V.; Esposito, G.; Moschini, G.; Sapora, O.; Signoretti, C.; Simone, G.; Sorrentino, E.; Tabocchini, M. A.

    Elucidation of how effects of densely ionizing radiation at cellular level are linked to DNA damage is fundamental for a better understanding of the mechanisms leading to genomic damage (especially chromosome aberrations) and developing biophysical models to predict space radiation effects. We have investigated the DNA fragmentation patterns induced in Chinese hamster V79 cells by 31 keV/μm protons, 123 keV/μm helium-4 ions and γ-rays in the size range 0.023-5.7 Mbp, using calibrated Pulsed Field Gel Electrophoresis (PFGE). The frequency distributions of fragments induced by the charged particles were shifted towards smaller sizes with respct to that induced by comparable doses of γ-rays. The DSB yields, evaluated from the fragments induced in the size range studied, were higher for protons and helium ions than for γ-rays by a factor of about 1.9 and 1.2, respectively. However, these ratios do not adequately reflect the RBE observed on the same cells for inactivation and mutation induced by these beams. This is a further indication for the lack of correlation between the effects exerted at cellular level and the initial yield of DSB. The dependence on radiation quality of the fragmentation pattern suggests that it may have a role in damage reparability. We have analyzed these patterns with a "random breakage" model generalized in order to consider the initial non-random distribution of the DNA molecules. Our results suggest that a random breakage mechanism can describe with a reasonable approximation the DNA fragmentation induced by γ-rays, while the approximation is not so good for light ions, likely due to the interplay between ion tracks and chromatin organization at the loop level.

  10. Changes in the NMR Metabolic Profile of Human Microglial Cells Exposed to Lipopolysaccharide or Morphine

    PubMed Central

    El Ghazi, Issam; Sheng, Wen S.; Hu, Shuxian; Reilly, Brian G.; Lokensgard, James R.; Rock, R. Bryan; Peterson, Phillip K.; Wilcox, George L.

    2014-01-01

    Microglial cells play a major role in host defense of the central nervous system. Once activated, several functional properties are up-regulated including migration, phagocytosis, and secretion of inflammatory mediators such as cytokines and chemokines. Little, if anything, is known about the metabolic changes that occur during the activation process. High-resolution 1H nuclear magnetic resonance spectra obtained from perchloric acid extracts of human microglial cell cultures exposed to lipopolysaccharide (LPS) or morphine were used to both identify and quantify the metabolites. We found that human microglia exposed to LPS had increased concentrations of glutamate and lactate, whereas the cells exposed to morphine had decreased concentrations in creatinine, taurine, and thymine. Glutamate and creatinine were the key metabolites differentiating between the two stimuli. These results are discussed in terms of activation and differences in the inflammatory response of human microglial cells to LPS and morphine. PMID:20333557

  11. 103. DETAIL OF ZINC CLEANER CELL INTERIOR (EXPOSED AT F/45 ...

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

    103. DETAIL OF ZINC CLEANER CELL INTERIOR (EXPOSED AT F/45 FOR DEPTH OF FIELD PURPOSES). NOTE GALIGHER STYLE BAFFLES AND TENDENCY OF ZINC TO BUILD UP ON CELL COMPONENTS. - Shenandoah-Dives Mill, 135 County Road 2, Silverton, San Juan County, CO

  12. Comparing genotoxic signatures in cord blood cells from neonates exposed in utero to zidovudine or tenofovir.

    PubMed

    Vivanti, Alexandre; Soheili, Tayebeh S; Cuccuini, Wendy; Luce, Sonia; Mandelbrot, Laurent; Lechenadec, Jerome; Cordier, Anne-Gael; Azria, Elie; Soulier, Jean; Cavazzana, Marina; Blanche, Stéphane; André-Schmutz, Isabelle

    2015-07-17

    Zidovudine and tenofovir are the two main nucleos(t)ide analogs used to prevent mother-to-child transmission of HIV. In vitro, both drugs bind to and integrate into human DNA and inhibit telomerase. The objective of the present study was to assess the genotoxic effects of either zidovudine or tenofovir-based combination therapies on cord blood cells in newborns exposed in utero. We compared the aneuploid rate and the gene expression profiles in cord blood samples from newborns exposed either to zidovudine or tenofovir-based combination therapies during pregnancy and from unexposed controls (n = 8, 9, and 8, respectively). The aneuploidy rate was measured on the cord blood T-cell karyotype. Gene expression profiles of cord blood T cells and hematopoietic stem and progenitor cells were determined with microarrays, analyzed in a gene set enrichment analysis and confirmed by real-time quantitative PCRs. Aneuploidy was more frequent in the zidovudine-exposed group (26.3%) than in the tenofovir-exposed group (14.2%) or in controls (13.3%; P < 0.05 for both). The transcription of genes involved in DNA repair, telomere maintenance, nucleotide metabolism, DNA/RNA synthesis, and the cell cycle was deregulated in samples from both the zidovudine and the tenofovir-exposed groups. Although tenofovir has a lower clastogenic impact than zidovudine, gene expression profiling showed that both drugs alter the transcription of DNA repair and telomere maintenance genes.

  13. Comparing genotoxic signatures in cord blood cells from neonates exposed in utero to zidovudine or tenofovir

    PubMed Central

    Vivanti, Alexandre; Soheili, Tayebeh S.; Cuccuini, Wendy; Luce, Sonia; Mandelbrot, Laurent; Lechenadec, Jerome; Cordier, Anne-Gael; Azria, Elie; Soulier, Jean; Cavazzana, Marina; Blanche, Stéphane; André-Schmutz, Isabelle

    2015-01-01

    Objectives: Zidovudine and tenofovir are the two main nucleos(t)ide analogs used to prevent mother-to-child transmission of HIV. In vitro, both drugs bind to and integrate into human DNA and inhibit telomerase. The objective of the present study was to assess the genotoxic effects of either zidovudine or tenofovir-based combination therapies on cord blood cells in newborns exposed in utero. Design: We compared the aneuploid rate and the gene expression profiles in cord blood samples from newborns exposed either to zidovudine or tenofovir-based combination therapies during pregnancy and from unexposed controls (n = 8, 9, and 8, respectively). Methods: The aneuploidy rate was measured on the cord blood T-cell karyotype. Gene expression profiles of cord blood T cells and hematopoietic stem and progenitor cells were determined with microarrays, analyzed in a gene set enrichment analysis and confirmed by real-time quantitative PCRs. Results: Aneuploidy was more frequent in the zidovudine-exposed group (26.3%) than in the tenofovir-exposed group (14.2%) or in controls (13.3%; P < 0.05 for both). The transcription of genes involved in DNA repair, telomere maintenance, nucleotide metabolism, DNA/RNA synthesis, and the cell cycle was deregulated in samples from both the zidovudine and the tenofovir-exposed groups. Conclusion: Although tenofovir has a lower clastogenic impact than zidovudine, gene expression profiling showed that both drugs alter the transcription of DNA repair and telomere maintenance genes. PMID:25513819

  14. Leukemia-related chromosomal loss detected in hematopoietic progenitor cells of benzene-exposed workers

    PubMed Central

    Zhang, Luoping; Lan, Qing; Ji, Zhiying; Li, Guilan; Shen, Min; Vermeulen, Roel; Guo, Weihong; Hubbard, Alan E.; McHale, Cliona M.; Rappaport, Stephen M.; Hayes, Richard B.; Linet, Martha S.; Yin, Songnian; Smith, Martyn T.; Rothman, Nathaniel

    2012-01-01

    Benzene exposure causes acute myeloid leukemia, and hematotoxicity, shown as suppression of mature blood and myeloid progenitor cell numbers. As the leukemia-related aneuploidies monosomy 7 and trisomy 8 previously had been detected in the mature peripheral blood cells of exposed workers, we hypothesized that benzene could cause leukemia through the induction of these aneuploidies in hematopoietic stem and progenitor cells. We measured loss and gain of chromosomes 7 and 8 by fluorescence in situ hybridization in interphase colony-forming unit-granulocyte-macrophage (CFU-GM) cells cultured from otherwise healthy benzene-exposed (n=28) and unexposed (n=14) workers. CFU-GM monosomy 7 and 8 levels (but not trisomy) were significantly increased in subjects exposed to benzene overall, compared to levels in the control subjects (p=0.0055 and p=0.0034, respectively). Levels of monosomy 7 and 8 were significantly increased in subjects exposed to <10 ppm (20%, p=0.0419 and 28%, p=0.0056, respectively) and ≥10 ppm (48%, p=0.0045 and 32%, p=0.0354) benzene, compared with controls, and significant exposure-response trends were detected (ptrend=0.0033 and 0.0057). These data show that monosomies 7 and 8 are produced in a dose-dependent fashion in the blood progenitor cells of workers exposed to benzene and may be mechanistically relevant biomarkers of early effect for benzene and other leukemogens. PMID:22643707

  15. B-cell infiltration in the respiratory mucosa of turkeys exposed to subtype C avian metapneumovirus.

    PubMed

    Cha, Ra Mi; Khatri, Mahesh; Sharma, Jagdev M

    2007-09-01

    Turkeys exposed to avian metapneumovirus (aMPV) subtype C showed extensive lymphoid cell infiltrations in the nasal turbinates of the upper respiratory tract. The cellular infiltration occurred after the first virus exposure but not after re-exposure. Quantitation of the relative proportions of mucosal immunoglobulin (Ig)A+, IgG+, and IgM+ cells in controls and virus-exposed turkeys revealed that at 7 days after the first virus exposure, when mucosal infiltration was well pronounced, there was a significant increase (P < 0.05) in the numbers of infiltrating IgA+ but not of IgG+ and IgM+ cells. After the second virus exposure, although the overall numbers of mucosal lymphoid cells were similar in the virus-exposed and control turkeys, the relative proportions of IgA+ and IgG+ cells were significantly higher in the virus-exposed turkeys (P < 0.05) than in controls. Furthermore, elevated levels of aMPV-specific IgA were detected in the nasal secretions and the bile of virus-exposed birds after the second but not after the first virus exposure. These results suggest, for the first time, the possible involvement of local mucosal immunoglobulins in the pathogenesis of aMPV in turkeys.

  16. High frequency of malaria-specific T cells in non-exposed humans.

    PubMed

    Zevering, Y; Amante, F; Smillie, A; Currier, J; Smith, G; Houghten, R A; Good, M F

    1992-03-01

    A major goal of current candidate malaria vaccines is to stimulate the expansion of clones of malaria-specific lymphocytes. We have examined the in vitro T cell responses of a group of malaria exposed and non-exposed adult Caucasian donors to recombinant circumsporozoite (CS) proteins, one of which is undergoing clinical trials, to blood-stage parasites, and to synthetic peptides copying the CS protein and defined blood-stage proteins. In nearly all individuals tested, CD4 T cell proliferation or lymphokine production occurred in response to whole parasite or CS protein stimulation, and T cells from many individuals responded to synthetic peptides. T cell responses were major histocompatibility complex-restricted, and stimulation of T cells with malaria parasites or CS protein did not appear to expand a population of T cell receptor gamma/delta cells. Malaria-specific responses were independent of prior malaria exposure, and in some cases exceeded the magnitude of response to tetanus toxoid. Specific T cells are present in high frequency in the peripheral blood of many donors who have never been exposed to malaria. Although malaria-specific CD4 T cells play an important role in immunity, these data question whether vaccines need to stimulate such cells, and focus attention on other aspects of malaria immunity which may be more critical to a successful vaccine.

  17. NOS expression is increased in endothelial cells exposed to plasma from women with preeclampsia.

    PubMed

    Davidge, S T; Baker, P N; Roberts, J M

    1995-09-01

    Endothelial cell function is proposed to be altered by a factor(s) in the maternal circulation of women with the pregnancy disorder preeclampsia. Our initial hypothesis was that in preeclampsia, such factor(s) would reduce synthesis of nitric oxide (NO) by endothelial cells. However, we previously observed increased NO synthase activity in endothelial cells exposed to plasma from preeclamptic women. This study tested whether exposing cells to plasma from preeclamptic women increased transcription and/or translation of endothelial NO synthase. Cultured bovine coronary microvascular endothelial cells were exposed to 2% plasma from patients with preeclampsia and patients with uncomplicated pregnancies. Nitrite production was greater in endothelial cells exposed to plasma from preeclamptic women (8.97 +/- 0.54 vs. 6.39 +/- 0.59 nmol nitrites.10(6) cells-1 x 24 h-1; P < 0.05). Similarly, endothelial NO synthase mass as measured by Western immunoblotting was significantly increased (20,980 +/- 1,406 vs. 15,047 +/- 1,003 absorbancy units; P < 0.02). There was no detectable difference in mRNA for endothelial NO synthase. However, actinomycin (3 micrograms/ml), a transcription inhibitor, significantly decreased nitrite production only in cells exposed to plasma from preeclamptic women (5.28 +/- 0.52 vs. 3.56 +/- 0.36 nmol.10(6) cells-1 x 24 h-1, P < 0.05). These findings indicate a regulation of the "constitutive" isoform of NO synthase by factor(s) in the blood of preeclamptic women, which may have significance in this pathological condition of pregnancy.

  18. Millimeter wave induced reversible externalization of phosphatidylserine molecules in cells exposed in vitro.

    PubMed

    Szabo, Imre; Kappelmayer, Janos; Alekseev, Stanislav I; Ziskin, Marvin C

    2006-04-01

    In vitro exposure of refrigerated samples (4 degrees C) of anti-coagulated blood with millimeter waves (MMWs) at incident power densities (IPDs) between 0.55 and 1.23 W/cm2 has been found to induce clot formation. We found a small but statistically significant change in clot size with increasing IPD value. MMW exposure of blood samples starting at room temperature (22 degrees C) did not induce blood coagulation; neither did conventional heating at temperatures up to 40 degrees C. Since cell-free plasma did not clot upon MMW exposure, the role of blood cells was particularly analyzed. Experiments on various mixtures of blood cells with plasma revealed an important role of red blood cells (RBC) in the coagulation process. Plasma coagulation also developed within the MMW beam above dense keratinocyte (HaCaT) monolayers suggesting it lacked cell-type specificity. We hypothesized that alteration of the membrane surface in exposed cells might be responsible for the circumscribed coagulation. The thrombogenic role of externalized phosphatidylserine (PS) molecules is well known. Therefore, we carried out experiments for immunolabeling PS molecules with fluorescein isothiocyanate (FITC)-conjugated Annexin V on exposed cells. Fluorescence microscopy of the adherent human keratinocytes (HaCaT) and murine melanoma cells (B16F10) showed that MMW exposure at an IPD of 1.23 W/cm2 is capable of inducing reversible externalization of PS molecules in cells within the beam area without detectable membrane damage. Nonadherent Jurkat cells exposed to MMW at an IPD of 34.5 mW/cm2 also showed reversible PS externalization with flow cytometry, whether the cell temperature was held constant or permitted to rise. These results suggest that certain biological effects induced by MMWs could be initiated by membrane changes in exposed cells.

  19. Increased frequency of micronucleated exfoliated cells among humans exposed in vivo to mobile telephone radiations.

    PubMed

    Yadav, Abhay Singh; Sharma, Manoj Kumar

    2008-02-29

    The health concerns have been raised following the enormous increase in the use of wireless mobile telephones throughout the world. This investigation had been taken, with the motive to find out whether mobile phone radiations cause any in vivo effects on the frequency of micronucleated exfoliated cells in the exposed subjects. A total of 109 subjects including 85 regular mobile phone users (exposed) and 24 non-users (controls) had participated in this study. Exfoliated cells were obtained by swabbing the buccal-mucosa from exposed as well as sex-age-matched controls. One thousand exfoliated cells were screened from each individual for nuclear anomalies including micronuclei (MN), karyolysis (KL), karyorrhexis (KH), broken egg (BE) and binucleated (BN) cells. The average daily duration of exposure to mobile phone radiations is 61.26 min with an overall average duration of exposure in term of years is 2.35 years in exposed subjects along with the 9.84+/-0.745 micronucleated cells (MNCs) and 10.72+/-0.889 total micronuclei (TMN) as compared to zero duration of exposure along with average 3.75+/-0.774 MNC and 4.00+/-0.808 TMN in controls. The means are significantly different in case of MNC and TMN at 0.01% level of significance. The mean of KL in controls is 13.17+/-2.750 and in exposed subjects is 13.06+/-1.793. The value of means of KH in exposed subjects (1.84+/-0.432) is slightly higher than in controls (1.42+/-0.737). Mean frequency of broken egg is found to be more in exposed subjects (0.65+/-0.276) as compared to controls (0.50+/-0.217). Frequency of presence of more than one nucleus in a cell (binucleated) is also higher in exposed (2.72+/-0.374) in comparison to controls (0.67+/-0.231). Although there is a slight increase in mean frequency of KH, BE and BN in exposed subjects but the difference is not found statistically significant. Correlation between 0-1, 1-2, 2-3 and 3-4 years of exposure and the frequency of MNC and TMN has been calculated and found to

  20. Cell cycle synchronization reveals greater G2/M-phase accumulation of lung epithelial cells exposed to titanium dioxide nanoparticles.

    PubMed

    Medina-Reyes, Estefany I; Bucio-López, Laura; Freyre-Fonseca, Verónica; Sánchez-Pérez, Yesennia; García-Cuéllar, Claudia M; Morales-Bárcenas, Rocío; Pedraza-Chaverri, José; Chirino, Yolanda I

    2015-03-01

    Titanium dioxide has been classified in the 2B group as a possible human carcinogen by the International Agency for Research on Cancer, and amid concerns of its exposure, cell cycle alterations are an important one. However, several studies show inconclusive effects, mainly because it is difficult to compare cell cycle effects caused by TiO2 nanoparticle (NP) exposure between different shapes and sizes of NP, cell culture types, and time of exposure. In addition, cell cycle is frequently analyzed without cell cycle synchronization, which may also mask some effects. We hypothesized that synchronization after TiO2 NP exposure could reveal dissimilar cell cycle progression when compared with unsynchronized cell population. To test our hypothesis, we exposed lung epithelial cells to 1 and 10 μg/cm(2) TiO2 NPs for 7 days and one population was synchronized by serum starvation and inhibition of ribonucleotide reductase using hydroxyurea. Another cell population was exposed to TiO2 NPs under the same experimental conditions, but after treatments, cell cycle was analyzed without synchronization. Our results showed that TiO2 NP-exposed cells without synchronization had no changes in cell cycle distribution; however, cell population synchronized after 1 and 10 μg/cm(2) TiO2 NP treatment showed a 1.5-fold and 1.66-fold increase, respectively, in proliferation. Synchronized cells also reveal a faster capability of TiO2 NP-exposed cells to increase cell population in the G2/M phase in the following 9 h after synchronization. We conclude that synchronization discloses a greater percentage of cells in the G2/M phase and higher proliferation than TiO2 NP-synchronized cells.

  1. NK Cell-derived Exosomes From NK Cells Previously Exposed to Neuroblastoma Cells Augment the Antitumor Activity of Cytokine-activated NK Cells.

    PubMed

    Shoae-Hassani, Alireza; Hamidieh, Amir Ali; Behfar, Maryam; Mohseni, Rashin; Mortazavi-Tabatabaei, Seyed A; Asgharzadeh, Shahab

    2017-09-01

    Immune cell-derived exosomes can increase immunity against tumors. In contrast, tumor-derived exosomes can reduce the immunity and can change the tumor microenvironment to further develop and provide metastasis. These effects take place by an alteration in the innate and adaptive immune cell functions. In this experiment, we studied the natural killer (NK) cells' effectiveness on tumor cells after expansion and thereafter incubated it with exosomes. The exosomes were derived from 2 populations of NK cells: (1) naive NK cells and, (2) NK cells previously exposed to neuroblastoma (NB) cells. Moreover, we have studied the NB-derived exosomes on NK cell function. The molecular load of the characterized exosomes (by means of nanoparticle-tracking analysis, flow cytometry, scanning electron microscopy, and western blot) from NK cells exposed to the NB cell revealed their expression of natural killer cell receptors in addition to CD56, NKG2D, and KIR2DL2 receptors. These exosomes were used to treat NK cells and thereafter administered to NB tumor cells both in vitro and in vivo. Our results showed some kind of NK cells' education by the exosomes. This education from NK cells previously exposed to NB cell-derived exosomes caused efficient and greater cytotoxicity against NB tumors, but NB-derived exosomes act as tumor promoters by providing a tumor supporting niche. Hence, this method of preparing the exosomes has a dramatic effect on activation of anti-NK cells against NB cells.

  2. Deficiency of INFgamma producing cells in adenoids of children exposed to passive smoke.

    PubMed

    Avanzini, M A; Ricci, A; Scaramuzza, C; Semino, L; Pagella, F; Castellazzi, A M; Marconi, M; Klersy, C; Pistorio, A; Boner, A L; Marseglia, G L

    2006-01-01

    Exposure to passive smoke is a very common event associated with increased susceptibility to respiratory tract infections. Many related adverse effects result from the ability of cigarette smoke extracts to interfere with the immune system, but the mechanism is not yet completely understood. The aim of the present study is to evaluate the intracellular cytokine profile in adenoids and peripheral blood cells of children exposed to passive smoke. Children undergoing adenoidectomy exposed or not exposed to passive smoke were studied. The intracellular cytokine profile of lymphocyte subsets in adenoids and in peripheral blood were evaluated by flow cytometry analysis. Children exposed to tobacco smoke showed a significantly lower percentage of INF-gamma producing CD4+ and CD8+ cells in adenoids. Moreover a significant correlation was observed between the quantity of exposure and reduction in Th1 (CD4+INFgamma+ and CD8+INFgamma+) cells in adenoids. This reduction may be a contributing factor in the increasing susceptibility to respiratory tract infection in children exposed to tobacco smoke.

  3. Metformin is also effective on lactic acidosis-exposed melanoma cells switched to oxidative phosphorylation.

    PubMed

    Peppicelli, Silvia; Toti, Alessandra; Giannoni, Elisa; Bianchini, Francesca; Margheri, Francesca; Del Rosso, Mario; Calorini, Lido

    2016-07-17

    Low extracellular pH promotes in melanoma cells a malignant phenotype characterized by an epithelial-to-mesenchymal transition (EMT) program, endowed with mesenchymal markers, high invasiveness and pro-metastatic property. Here, we demonstrate that melanoma cells exposed to an acidic extracellular microenvironment, 6.7±0.1, shift to an oxidative phosphorylation (Oxphos) metabolism. Metformin, a biguanide commonly used for type 2 diabetes, inhibited the most relevant features of acid-induced phenotype, including EMT and Oxphos. When we tested effects of lactic acidosis, to verify whether sodium lactate might have additional effects on acidic melanoma cells, we found that EMT and Oxphos also characterized lactic acid-treated cells. An increased level of motility was the only gained property of lactic acidic-exposed melanoma cells. Metformin treatment inhibited both EMT markers and Oxphos and, when its concentration raised to 10 mM, it induced a striking inhibition of proliferation and colony formation of acidic melanoma cells, both grown in protons enriched medium or lactic acidosis. Thus, our study provides the first evidence that metformin may target either proton or lactic acidosis-exposed melanoma cells inhibiting EMT and Oxphox metabolism. These findings disclose a new potential rationale of metformin addition to advanced melanoma therapy, e.g. targeting acidic cell subpopulation.

  4. Dual Functionality of Myeloperoxidase in Rotenone-Exposed Brain-Resident Immune Cells

    PubMed Central

    Chang, Chi Young; Song, Mi Jeon; Jeon, Sae-Bom; Yoon, Hee Jung; Lee, Dae Kee; Kim, In-Hoo; Suk, Kyungho; Choi, Dong-Kug; Park, Eun Jung

    2011-01-01

    Rotenone exposure has emerged as an environmental risk factor for inflammation-associated neurodegenerative diseases. However, the underlying mechanisms responsible for the harmful effects of rotenone in the brain remain poorly understood. Herein, we report that myeloperoxidase (MPO) may have a potential regulatory role in rotenone-exposed brain-resident immune cells. We show that microglia, unlike neurons, do not undergo death; instead, they exhibit distinctive activated properties under rotenone-exposed conditions. Once activated by rotenone, microglia show increased production of reactive oxygen species, particularly HOCl. Notably, MPO, an HOCl-producing enzyme that is undetectable under normal conditions, is significantly increased after exposure to rotenone. MPO-exposed glial cells also display characteristics of activated cells, producing proinflammatory cytokines and increasing their phagocytic activity. Interestingly, our studies with MPO inhibitors and MPO-knockout mice reveal that MPO deficiency potentiates, rather than inhibits, the rotenone-induced activated state of glia and promotes glial cell death. Furthermore, rotenone-triggered neuronal injury was more apparent in co-cultures with glial cells from Mpo−/− mice than in those from wild-type mice. Collectively, our data provide evidence that MPO has dual functionality under rotenone-exposed conditions, playing a critical regulatory role in modulating pathological and protective events in the brain. PMID:21704008

  5. Phenotypic characterisation of peripheral blood lymphoid cells in people exposed to fibrous zeolite.

    PubMed Central

    Ozesmi, M; Karlsson-Parra, A; Hillerdal, G; Forsum, U

    1986-01-01

    Among inhabitants of the village of Karain in Turkey there is an extremely high incidence of malignant mesothelioma, most probably due to exposure to erionite, which is a fibrous zeolite and similar in appearance and properties to asbestos. This mineral may be found in the dust in the village. To characterise possible disturbances in the immune system of people exposed to fibrous zeolite, a phenotypic characterisation of lymphoid cells in the peripheral blood of 74 immigrants to Sweden from Karain was performed. Compared with normal controls, the mean percentages of Leu 4+ cells (Pan-T) and Leu 3a+ cells ("helper/inducer" T cells) were significantly decreased, whereas the mean percentage of Leu 2a+ cells ("suppressor/cytotoxic" T cells) was normal, leading to a significant reduction of the Leu 3a/Leu 2a subset ratio. The percentage of B cells (Leu 12+ cells) was significantly increased, whereas the percentages of both HLA-DR+ and HLA-DQ+ cells were normal. The percentage of natural killer cells (NK) and killer (K) cells as defined by the monoclonal anti-Leu 7 and anti-Leu 11b were also normal. These findings indicate that exposure to fibrous zeolite causes a numerical imbalance between the two phenotypically different T cell subsets similar to that seen in asbestos exposed individuals. PMID:3026434

  6. NF-κB Decoy Oligodeoxynucleotide Enhanced Osteogenesis in Mesenchymal Stem Cells Exposed to Polyethylene Particle

    PubMed Central

    Lin, Tzu-Hua; Sato, Taishi; Barcay, Katherine R.; Waters, Heather; Loi, Florence; Zhang, Ruth; Pajarinen, Jukka; Egashira, Kensuke; Yao, Zhenyu

    2015-01-01

    Excessive generation of wear particles after total joint replacement may lead to local inflammation and periprosthetic osteolysis. Modulation of the key transcription factor NF-κB in immune cells could potentially mitigate the osteolytic process. We previously showed that local delivery of ultrahigh-molecular-weight polyethylene (UHMWPE) particles recruited osteoprogenitor cells and reduced osteolysis. However, the biological effects of modulating the NF-κB signaling pathway on osteoprogenitor/mesenchymal stem cells (MSCs) remain unclear. Here we showed that decoy oligodeoxynucleotide (ODN) increased cell viability when primary murine MSCs were exposed to UHMWPE particles, but had no effects on cellular apoptosis. Decoy ODN increased transforming growth factor-beta 1 (TGF-β1) and osteoprotegerin (OPG) in MSCs exposed to UHMWPE particles. Mechanistic studies showed that decoy ODN upregulated OPG expression through a TGF-β1-dependent pathway. By measuring the alkaline phosphatase activity, osteocalcin levels, Runx2 and osteopontin expression, and performing a bone mineralization assay, we found that decoy ODN increased MSC osteogenic ability when the cells were exposed to UHMWPE particles. Furthermore, the cellular response to decoy ODN and UHMWPE particles with regard to cell phenotype, cell viability, and osteogenic ability was confirmed using primary human MSCs. Our results suggest that modulation of wear particle-induced inflammation by NF-κB decoy ODN had no adverse effects on MSCs and may potentially further mitigate periprosthetic osteolysis by protecting MSC viability and osteogenic ability. PMID:25518013

  7. Neighbor effect: penumbra-dose exposed neighbor cells contribute to the enhanced survival of high-dose targeted cells.

    PubMed

    Lee, Min-Ho; Lee, Ki-Man; Kim, Eun-Hee

    2017-08-16

    In the last decade, new types of 'bystander effect' have been suggested by multiple research groups and have been challenged by others. In this study, we explored a new type of bystander effect, which has been defined in previous studies as the enhancement of the survival of high-dose targeted cells due to the penumbra-dose exposed neighbor cells. Intensity-modulated radiation therapy, which is the most widely used treatment modality, generates local regions of gradient doses between targeted and shielded cells throughout the treatment volume; therefore, we were urged to ascertain whether the new type of effect is real and to suggest a revised treatment planning. Cellular responses under non-uniform beam fields were observed in rat gliosarcoma cells, rat diencephalon cells, and mouse endothelial cells. The cells were irradiated with 200 kVp X-rays in two types: (1) all the cells in the flask were exposed to the X-ray beam (whole-beam exposure) and (2) half of the cells in the flask were exposed to the beam while the other half, or neighbor cells, were shielded from the beam (half-beam exposure). Target cells were exposed to 1, 2, 4, 6, 8, and 10 Gy, and the penumbra dose was approximately 10%-20% of the target dose. Target cells survived high-dose (> 6 Gy) radiation exposures better under half-beam exposure with the low penumbra-dose exposed neighbor cells around than under whole-beam exposure. The survival of the targeted cells from half-beam exposure was reduced when the radiation self-conditioned medium was replaced with a fresh one immediately after irradiation. Survival was further reduced when the targeted cells were harvested immediately after irradiation and incubated in new dishes with fresh culture media until the colony was counted. We have collected data of good statistics by several post-irradiation treatments of targeted cells to ascertain that the new type of bystander effect is real. The low penumbra-dose exposed neighbor cells benefited the

  8. Determining adaptive and adverse oxidative stress responses in human bronical epithelial cells exposed to zinc

    EPA Science Inventory

    Determining adaptive and adverse oxidative stress responses in human bronchial epithelial cells exposed to zincJenna M. Currier1,2, Wan-Yun Cheng1, Rory Conolly1, Brian N. Chorley1Zinc is a ubiquitous contaminant of ambient air that presents an oxidant challenge to the human lung...

  9. SIGNALING MECHANISMS IN HUMAN AIRWAY EPITHELIAL CELLS EXPOSED TO CARBON ULTRAFINE PARTICLES

    EPA Science Inventory

    SIGNALING MECHANISMS IN HUMAN AIRWAY EPITHELIAL CELLS EXPOSED TO CARBON ULTRAFINE PARTICLES
    Y.M. Kim, A.G. Lenz, R. Silbajoris, I. Jaspers and J.M. Samet. Department of Environmental Sciences and Engineering and Center for Environmental Medicine, University of North Carolina, ...

  10. SIGNALING MECHANISMS IN HUMAN AIRWAY EPITHELIAL CELLS EXPOSED TO CARBON ULTRAFINE PARTICLES

    EPA Science Inventory

    SIGNALING MECHANISMS IN HUMAN AIRWAY EPITHELIAL CELLS EXPOSED TO CARBON ULTRAFINE PARTICLES
    Y.M. Kim, A.G. Lenz, R. Silbajoris, I. Jaspers and J.M. Samet. Department of Environmental Sciences and Engineering and Center for Environmental Medicine, University of North Carolina, ...

  11. Determining adaptive and adverse oxidative stress responses in human bronical epithelial cells exposed to zinc

    EPA Science Inventory

    Determining adaptive and adverse oxidative stress responses in human bronchial epithelial cells exposed to zincJenna M. Currier1,2, Wan-Yun Cheng1, Rory Conolly1, Brian N. Chorley1Zinc is a ubiquitous contaminant of ambient air that presents an oxidant challenge to the human lung...

  12. Antioxidant enzyme activities of human peripheral blood mononuclear cells exposed to trace elements.

    PubMed

    Kuppusamy, U R; Dharmani, M; Kanthimathi, M S; Indran, M

    2005-07-01

    The trace elements copper, zinc, and selenium are important immune modulators and essential cofactors of the antioxidant enzymes. In the present study, the proliferative effect of human peripheral mononuclear cells (PBMCs) that have been exposed to copper, zinc, and selenium and the corresponding activities of antioxidant enzymes, namely superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase, were determined. Zinc and copper stimulated the PBMC proliferation in a dose-dependent manner within the dose range 25-200 micromol/L. SOD and GPx activities in PBMCs exposed to zinc were inhibited, whereas catalase activity was unaffected. All the three antioxidant enzymes in the cells exposed to copper were inhibited. Selenium exerted more potent inhibition of the cell proliferation while causing stimulation of the antioxidant enzymes at the lowest dose (25 micromol/L) than at the highest dose (200 micromol/L) tested. A significant negative correlation was observed between proliferation and antioxidant enzyme (SOD and GPx) activities in trace-element-exposed PBMC. The present findings substantiate the importance of trace elements as immune modulators and the involvement of enzymatic antioxidant system in the immune cell regulation.

  13. Ultrastructure of cells of Ulmus americana cultured in vitro and exposed to the culture filtrate of Ceratocystis ulmi

    Treesearch

    Paula M. Pijut; R. Daniel Lineberger; Subhash C. Domir; Jann M. Ichida; Charles R. Krause

    1990-01-01

    Calli of American elm susceptible and resistant to Dutch elm disease were exposed to a culture filtrate of a pathogenic isolate of Ceratocystis ulmi. Cells from untreated tissue exhibited typical internal composition associated with healthy, actively growing cells. All cells exposed to culture filtrate showed appreciable ultrastructural changes....

  14. {sub p}53-Dependent Adaptive Responses in Human Cells Exposed to Space Radiations

    SciTech Connect

    Takahashi, Akihisa; Su Xiaoming; Suzuki, Hiromi; Omori, Katsunori; Seki, Masaya; Hashizume, Toko; Shimazu, Toru; Ishioka, Noriaki; Iwasaki, Toshiyasu; Ohnishi, Takeo

    2010-11-15

    Purpose: It has been reported that priming irradiation or conditioning irradiation with a low dose of X-rays in the range of 0.02-0.1 Gy induces a p53-dependent adaptive response in mammalian cells. The aim of the present study was to clarify the effect of space radiations on the adaptive response. Methods and Materials: Two human lymphoblastoid cell lines were used; one cell line bears a wild-type p53 (wtp53) gene, and another cell line bears a mutated p53 (mp53) gene. The cells were frozen during transportation on the space shuttle and while in orbit in the International Space Station freezer for 133 days between November 15, 2008 and March 29, 2009. After the frozen samples were returned to Earth, the cells were cultured for 6 h and then exposed to a challenging X-ray-irradiation (2 Gy). Cellular sensitivity, apoptosis, and chromosome aberrations were scored using dye-exclusion assays, Hoechst33342 staining assays, and chromosomal banding techniques, respectively. Results: In cells exposed to space radiations, adaptive responses such as the induction of radioresistance and the depression of radiation-induced apoptosis and chromosome aberrations were observed in wtp53 cells but not in mp53 cells. Conclusion: These results have confirmed the hypothesis that p53-dependent adaptive responses are apparently induced by space radiations within a specific range of low doses. The cells exhibited this effect owing to space radiations exposure, even though the doses in space were very low.

  15. Lymphocyte toxicity and T cell receptor excision circles in workers exposed to benzene.

    PubMed

    Lan, Qing; Zhang, Luoping; Hakim, Fran; Shen, Min; Memon, Sarfraz; Li, Guilan; Vermeulen, Roel; Smith, Martyn T; Rappaport, Stephen M; Hayes, Richard; Linet, Martha; Yin, Songnian; Rothman, Nathaniel; Rabkin, Charles S

    2005-05-30

    We have previously reported that benzene decreases peripheral white blood cell and platelet counts and specifically lowers subsets of several blood cell types, including CD4+-T cells, B cells, NK cells, and granulocytes. Diminished thymus function has been implicated as a mechanism for CD4+-T cell loss in other conditions such as AIDS by assays of T cell receptor excision circles (TRECs), a marker of naive T cells that have recently emigrated from the thymus. To evaluate alteration of thymic function as a mechanism for benzene's effects on CD4+-T cell counts, we measured total TREC levels in 45 benzene-exposed workers and 45 unexposed controls. There was no significant difference in TREC levels per 10(6) peripheral blood leukocytes in the benzene-exposed workers compared to the controls. Although our study does not rule out counterbalancing alterations of TREC levels in specific T cell subsets, benzene's lymphotoxicity does not appear to be mediated through diminished thymus function.

  16. Bystander cell proliferation is modulated by the number of adjacent cells that were exposed to ionizing radiation.

    PubMed

    Gerashchenko, Bogdan I; Howell, Roger W

    2005-07-01

    Direct cell-to-cell contact appears to be a prerequisite for the proliferative response of bystander WB-F344 cells co-cultured with irradiated cells; however, neither gap junctional intercellular communication nor long-range factors released into the medium appear to be involved (Cytometry 2003;56A:71-80). The present work investigated whether the proliferative bystander response depends on the number of irradiated cells (cells exposed to external gamma-rays or cells exposed to short-range beta-particles emitted by DNA-incorporated (3)H-thymidine) that are adjacent to unirradiated bystander cells. Subconfluent monolayers of rat liver epithelial cells (WB-F344) were incubated in the presence of (methyl-(3)H)thymidine at a concentration of 5.8 kBq/ml for 18 h. Radiolabeled cells containing 0.7 x 10(-3) Bq/cell (absorbed dose: 0.14 Gy) were plated together with unlabeled cells in proportions of 6% and 94%, 12% and 88%, 25% and 75%, 50% and 50%, and 75% and 25%, respectively, keeping constant the total number of plated cells. In a parallel experiment, cells acutely exposed to 5 Gy of (137)Cs gamma-rays were plated with unirradiated cells in the same proportions. In both experiments, cells were co-cultured for 24 h followed by a flow cytometric study of their proliferation. The two cell populations in the co-cultures were distinguished by staining one population with carboxyfluorescein diacetate, succinimidyl ester, which metabolizes intracellularly. Increasing the fraction of irradiated cells relative to unirradiated bystander cells led to an increase in proliferation of bystander cells. Specifically, in co-cultures in which irradiated cells were initially mixed with unirradiated cells in proportions of 50% and 50% and of 75% and 25%, respectively, bystander cells showed a statistically significant increase of their proliferation compared with the controls. The proliferative response of WB-F344 bystander cells is modulated by the number of adjacent cells that are

  17. Increased radioresistance of tumor cells exposed to metallothionein-inducing agents

    SciTech Connect

    Renan, M.J.; Dowman, P.I. )

    1989-12-01

    In this study, we have determined the radiosensitivity parameters of cells exposed in vitro to metallothionein-inducing agents. Three well-characterized tumor cell lines were chosen for investigation: HeLa, B16, and WHFIB. We have shown that exposure of cells in vitro to a heavy metal (cadmium), followed by irradiation, enhances cell survival for two out of three cell lines studied. As measured by the mean inactivation dose, the radioresistance increases by a factor of 1.6 for HeLa cells, 1.4 for WHFIB, and a negligible factor for B16 cells. An additional effect was noted when different classes of metallothionein inducers (such as serum factors, cadmium, and dexamethasone) were allowed to act together. Also, we found that the increase in radioresistance exhibits a peak at exposure times of approximately 10 h; longer exposure to inducing agents results in a reduction in radioresistance.

  18. In vitro metabolism study of normal and tumor cells when exposed to red LED light

    NASA Astrophysics Data System (ADS)

    Stolbovskaya, Olga V.; Khairullin, Radik M.; Saenko, Yuri V.; Krasnikova, Ekaterina S.; Krasnikov, Aleksandr V.; Fomin, Aleksandr A.; Skaptsov, Aleksandr A.

    2016-04-01

    This work presents the results of studying the mitochondrial membrane potential, intracellular ROS, peculiarities of the cell cycle of cancer cells HCT-116 and the normal line of CHO cells when exposed to the red LED light with a wavelength range of 0.620-0.680 μm. A dose-dependent increase in mitochondrial membrane potential and intracellular ROS concentration in cancer cells HCT-116 was established. In normal CHO cell line a dose-dependent reduction of mitochondrial membrane potential and dose-dependent increase in intracellular ROS occur. It has been shown that the sensitivity of the studied cell lines to the red light depends on the stage of the cell cycle.

  19. Protein C Inhibitor (PCI) Binds to Phosphatidylserine Exposing Cells with Implications in the Phagocytosis of Apoptotic Cells and Activated Platelets

    PubMed Central

    Rieger, Daniela; Assinger, Alice; Einfinger, Katrin; Sokolikova, Barbora; Geiger, Margarethe

    2014-01-01

    Protein C Inhibitor (PCI) is a secreted serine protease inhibitor, belonging to the family of serpins. In addition to activated protein C PCI inactivates several other proteases of the coagulation and fibrinolytic systems, suggesting a regulatory role in hemostasis. Glycosaminoglycans and certain negatively charged phospholipids, like phosphatidylserine, bind to PCI and modulate its activity. Phosphatidylerine (PS) is exposed on the surface of apoptotic cells and known as a phagocytosis marker. We hypothesized that PCI might bind to PS exposed on apoptotic cells and thereby influence their removal by phagocytosis. Using Jurkat T-lymphocytes and U937 myeloid cells, we show here that PCI binds to apoptotic cells to a similar extent at the same sites as Annexin V, but in a different manner as compared to live cells (defined spots on ∼10–30% of cells). PCI dose dependently decreased phagocytosis of apoptotic Jurkat cells by U937 macrophages. Moreover, the phagocytosis of PS exposing, activated platelets by human blood derived monocytes declined in the presence of PCI. In U937 cells the expression of PCI as well as the surface binding of PCI increased with time of phorbol ester treatment/macrophage differentiation. The results of this study suggest a role of PCI not only for the function and/or maturation of macrophages, but also as a negative regulator of apoptotic cell and activated platelets removal. PMID:25000564

  20. Bacterial growth in red blood cell units exposed to uncontrolled temperatures: challenging the 30-minute rule.

    PubMed

    Ramirez-Arcos, S; Perkins, H; Kou, Y; Mastronardi, C; Kumaran, D; Taha, M; Yi, Q-L; McLaughlin, N; Kahwash, E; Lin, Y; Acker, J

    2013-08-01

    The '30-min rule' requires discarding red blood cells (RBCs) exposed to uncontrolled temperatures for >30 min to ensure safe RBC transfusion. This study was aimed at determining whether multiple room temperature (RT) exposures promote bacterial growth. Pooled and split RBC units were inoculated with ~1 CFU/ml of Serratia marcescens, Yersinia enterocolitica, Escherichia coli or Staphylococcus epidermidis. Control units remained in storage, while test units were exposed to RT for six 30-min or three 60-min intervals. Bacterial concentrations and endotoxin levels were determined after each exposure and at 42 days of storage. RBC core temperature and RT were monitored in mock units with Escort iLog temperature loggers. A mixed model was used for statistical analyses. Red blood cell core temperature reached 10.7 ± 0.4°C and 14.2 ± 0.2°C during 30- and 60-min exposures, respectively. Staphylococcus epidermidis and E. coli did not grow in either control or exposed RBCs. Yersinia enterocolitica concentration and endotoxin levels were similar in both control and test units. Serratia marcescens concentration and endotoxin levels were higher in exposed units; however, differences between units exposed for 30 min or 60 min were not observed. There is no added risk to RBC safety by increasing RT exposures to 60 min with each removal from storage for up to a total of 3 h during RBC shelf life. Therefore, extending the 30-min limitation in RBCs exposed to uncontrolled temperatures to 60 min should be considered by regulatory agencies. © 2013 International Society of Blood Transfusion.

  1. Increased Myeloid Cell Production and Lung Bacterial Clearance in Mice Exposed to Cigarette Smoke.

    PubMed

    Basilico, Paola; Cremona, Tiziana P; Oevermann, Anna; Piersigilli, Alessandra; Benarafa, Charaf

    2016-03-01

    Pneumonia is a leading cause of hospitalization in patients with chronic obstructive pulmonary disease (COPD). Although most patients with COPD are smokers, the effects of cigarette smoke exposure on clearance of lung bacterial pathogens and on immune and inflammatory responses are incompletely defined. Here, clearance of Streptococcus pneumoniae and Pseudomonas aeruginosa and associated immune responses were examined in mice exposed to cigarette smoke or after smoking cessation. Mice exposed to cigarette smoke for 6 weeks or 4 months demonstrated decreased lung bacterial burden compared with air-exposed mice when infected 16 to 24 hours after exposure. When infection was performed after smoke cessation, bacterial clearance kinetics of mice previously exposed to smoke reversed to levels comparable to those of control mice, suggesting that the observed defects were not dependent on adaptive immunological memory to bacterial determinants found in smoke. Comparing cytokine levels and myeloid cell production before infection in mice exposed to cigarette smoke with mice never exposed or after smoke cessation revealed that reduced bacterial burden was most strongly associated with higher levels of IL-1β and granulocyte-macrophage colony-stimulating factor in the lungs and with increased neutrophil reserve and monocyte turnover in the bone marrow. Using Serpinb1a-deficient mice with reduced neutrophil numbers and treatment with granulocyte colony-stimulating factor showed that increased neutrophil numbers contribute only in part to the effect of smoke on infection. Our findings indicate that cigarette smoke induces a temporary and reversible increase in clearance of lung pathogens, which correlates with local inflammation and increased myeloid cell output from the bone marrow.

  2. The transcriptome of HIV-1 infected intestinal CD4+ T cells exposed to enteric bacteria.

    PubMed

    Yoder, Alyson C; Guo, Kejun; Dillon, Stephanie M; Phang, Tzu; Lee, Eric J; Harper, Michael S; Helm, Karen; Kappes, John C; Ochsenbauer, Christina; McCarter, Martin D; Wilson, Cara C; Santiago, Mario L

    2017-02-01

    Global transcriptome studies can help pinpoint key cellular pathways exploited by viruses to replicate and cause pathogenesis. Previous data showed that laboratory-adapted HIV-1 triggers significant gene expression changes in CD4+ T cell lines and mitogen-activated CD4+ T cells from peripheral blood. However, HIV-1 primarily targets mucosal compartments during acute infection in vivo. Moreover, early HIV-1 infection causes extensive depletion of CD4+ T cells in the gastrointestinal tract that herald persistent inflammation due to the translocation of enteric microbes to the systemic circulation. Here, we profiled the transcriptome of primary intestinal CD4+ T cells infected ex vivo with transmitted/founder (TF) HIV-1. Infections were performed in the presence or absence of Prevotella stercorea, a gut microbe enriched in the mucosa of HIV-1-infected individuals that enhanced both TF HIV-1 replication and CD4+ T cell death ex vivo. In the absence of bacteria, HIV-1 triggered a cellular shutdown response involving the downregulation of HIV-1 reactome genes, while perturbing genes linked to OX40, PPAR and FOXO3 signaling. However, in the presence of bacteria, HIV-1 did not perturb these gene sets or pathways. Instead, HIV-1 enhanced granzyme expression and Th17 cell function, inhibited G1/S cell cycle checkpoint genes and triggered downstream cell death pathways in microbe-exposed gut CD4+ T cells. To gain insights on these differential effects, we profiled the gene expression landscape of HIV-1-uninfected gut CD4+ T cells exposed to bacteria. Microbial exposure upregulated genes involved in cellular proliferation, MAPK activation, Th17 cell differentiation and type I interferon signaling. Our findings reveal that microbial exposure influenced how HIV-1 altered the gut CD4+ T cell transcriptome, with potential consequences for HIV-1 susceptibility, cell survival and inflammation. The HIV-1- and microbe-altered pathways unraveled here may serve as a molecular blueprint

  3. The transcriptome of HIV-1 infected intestinal CD4+ T cells exposed to enteric bacteria

    PubMed Central

    Dillon, Stephanie M.; Phang, Tzu; Lee, Eric J.; Helm, Karen; Kappes, John C.; McCarter, Martin D.

    2017-01-01

    Global transcriptome studies can help pinpoint key cellular pathways exploited by viruses to replicate and cause pathogenesis. Previous data showed that laboratory-adapted HIV-1 triggers significant gene expression changes in CD4+ T cell lines and mitogen-activated CD4+ T cells from peripheral blood. However, HIV-1 primarily targets mucosal compartments during acute infection in vivo. Moreover, early HIV-1 infection causes extensive depletion of CD4+ T cells in the gastrointestinal tract that herald persistent inflammation due to the translocation of enteric microbes to the systemic circulation. Here, we profiled the transcriptome of primary intestinal CD4+ T cells infected ex vivo with transmitted/founder (TF) HIV-1. Infections were performed in the presence or absence of Prevotella stercorea, a gut microbe enriched in the mucosa of HIV-1-infected individuals that enhanced both TF HIV-1 replication and CD4+ T cell death ex vivo. In the absence of bacteria, HIV-1 triggered a cellular shutdown response involving the downregulation of HIV-1 reactome genes, while perturbing genes linked to OX40, PPAR and FOXO3 signaling. However, in the presence of bacteria, HIV-1 did not perturb these gene sets or pathways. Instead, HIV-1 enhanced granzyme expression and Th17 cell function, inhibited G1/S cell cycle checkpoint genes and triggered downstream cell death pathways in microbe-exposed gut CD4+ T cells. To gain insights on these differential effects, we profiled the gene expression landscape of HIV-1-uninfected gut CD4+ T cells exposed to bacteria. Microbial exposure upregulated genes involved in cellular proliferation, MAPK activation, Th17 cell differentiation and type I interferon signaling. Our findings reveal that microbial exposure influenced how HIV-1 altered the gut CD4+ T cell transcriptome, with potential consequences for HIV-1 susceptibility, cell survival and inflammation. The HIV-1- and microbe-altered pathways unraveled here may serve as a molecular blueprint

  4. α1-Antitrypsin reduces rhinovirus infection in primary human airway epithelial cells exposed to cigarette smoke.

    PubMed

    Berman, Reena; Jiang, Di; Wu, Qun; Chu, Hong Wei

    2016-01-01

    Human rhinovirus (HRV) infections target airway epithelium and are the leading cause of acute exacerbations of COPD. Cigarette smoke (CS) increases the severity of viral infections, but there is no effective therapy for HRV infection. We determined whether α1-antitrypsin (A1AT) reduces HRV-16 infection in CS-exposed primary human airway epithelial cells. Brushed bronchial epithelial cells from normal subjects and patients diagnosed with COPD were cultured at air-liquid interface to induce mucociliary differentiation. These cells were treated with A1AT or bovine serum albumin for 2 hours and then exposed to air or whole cigarette smoke (WCS) with or without HRV-16 (5×10(4) 50% Tissue Culture Infective Dose [TCID50]/transwell) infection for 24 hours. WCS exposure significantly increased viral load by an average of fivefold and decreased the expression of antiviral genes interferon-λ1, OAS1, and MX1. When A1AT was added to WCS-exposed cells, viral load significantly decreased by an average of 29-fold. HRV-16 infection significantly increased HRV-16 receptor intercellular adhesion molecule-1 messenger RNA expression in air-exposed cells, which was decreased by A1AT. A1AT-mediated reduction of viral load was not accompanied by increased epithelial antiviral gene expression or by inhibiting the activity of 3C protease involved in viral replication or maturation. Our findings demonstrate that A1AT treatment prevents a WCS-induced increase in viral load and for the first time suggest a therapeutic effect of A1AT on HRV infection.

  5. BOSS on EXPOSE-R2-Comparative Investigations on Biofilm and Planktonic cells of Deinococcus geothermalis as Mission Preparation Tests

    NASA Astrophysics Data System (ADS)

    Panitz, C.; Rettberg, P.; Frösler, J.; Flemming, H.-C.; Rabbow, E.; Reitz, G.

    2013-09-01

    Biofilms are of interest for Astrobiological investigations since they are one of the oldest clear signs of life on Earth. In the experiment BOSS the hypothesis will be tested if the biofilm form of life with microorganisms embedded and aggregated in their EPS matrix is suited to support long-term survival of microorganisms under the harsh environmental conditions as they exist in space and on Mars and is superior to the same bacteria in the form of planktonic cultures. An additional protective role may be provided by particles associated in biofilms which may shield the organisms against radiation. The experiment will be flown on EXPOSE-R2 attached outside of the ISS on the Russian module. BOSS has participated the Experiment verification tests and will attend the upcoming Science verification test carried out in the Planetary and Space Simulation Facilities at DLR. The launch is scheduled for April 2014.

  6. Dose-Dependent Metabolic Alterations in Human Cells Exposed to Gamma Irradiation

    PubMed Central

    Kwon, Yong-Kook; Ha, In Jin; Bae, Hyun-Whee; Jang, Won Gyo; Yun, Hyun Jin; Kim, So Ra; Lee, Eun Kyeong; Kang, Chang-Mo; Hwang, Geum-Sook

    2014-01-01

    Radiation exposure is a threat to public health because it causes many diseases, such as cancers and birth defects, due to genetic modification of cells. Compared with the past, a greater number of people are more frequently exposed to higher levels of radioactivity today, not least due to the increased use of diagnostic and therapeutic radiation-emitting devices. In this study, ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS)-based metabolic profiling was used to investigate radiation- induced metabolic changes in human fibroblasts. After exposure to 1 and 5 Gy of γ-radiation, the irradiated fibroblasts were harvested at 24, 48, and 72 h and subjected to global metabolite profiling analysis. Mass spectral peaks of cell extracts were analyzed by pattern recognition using principal component analysis (PCA) and partial least squares-discriminant analysis (PLS-DA). The results showed that the cells irradiated with 1 Gy returned to control levels at 72 h post radiation, whereas cells irradiated with 5 Gy were quite unlike the controls; therefore, cells irradiated with 1 Gy had recovered, whereas those irradiated with 5 Gy had not. Lipid and amino acid levels increased after the higher-level radiation, indicating degradation of membranes and proteins. These results suggest that MS-based metabolite profiling of γ-radiation-exposed human cells provides insight into the global metabolic alterations in these cells. PMID:25419661

  7. Static electric fields interfere in the viability of cells exposed to ionising radiation.

    PubMed

    Arruda-Neto, João D T; Friedberg, Errol C; Bittencourt-Oliveira, Maria C; Cavalcante-Silva, Erika; Schenberg, Ana C G; Rodrigues, Tulio E; Garcia, Fermin; Louvison, Monica; Paula, Claudete R; Mesa, Joel; Moron, Michelle M; Maria, Durvanei A; Genofre, Godofredo C

    2009-04-01

    The interference of electric fields (EF) with biological processes is an issue of considerable interest. No studies have as yet been reported on the combined effect of EF plus ionising radiation. Here we report studies on this combined effect using the prokaryote Microcystis panniformis, the eukaryote Candida albicans and human cells. Cultures of Microcystis panniformis (Cyanobacteria) in glass tubes were irradiated with doses in the interval 0.5-5 kGy, using a (60)Co gamma source facility. Samples irradiated with 3 kGy were exposed for 2 h to a 20 V . cm(-1) static electric field and viable cells were enumerated. Cultures of Candida albicans were incubated at 36 degrees C for 20 h, gamma-irradiated with doses from 1-4 kGy, and submitted to an electric field of 180 V . cm(-1). Samples were examined under a fluorescence microscope and the number of unviable (red) and viable (apple green fluorescence) cells was determined. For crossing-check purposes, MRC5 strain of lung cells were irradiated with 2 Gy, exposed to an electric field of 1250 V/cm, incubated overnight with the anti-body anti-phospho-histone H2AX and examined under a fluorescence microscope to quantify nuclei with gamma-H2AX foci. In cells exposed to EF, death increased substantially compared to irradiation alone. In C. albicans we observed suppression of the DNA repair shoulder. The effect of EF in growth of M. panniformis was substantial; the number of surviving cells on day-2 after irradiation was 12 times greater than when an EF was applied. By the action of a static electric field on the irradiated MRC5 cells the number of nuclei with gamma-H2AX foci increased 40%, approximately. Application of an EF following irradiation greatly increases cell death. The observation that the DNA repair shoulder in the survival curve of C. albicans is suppressed when cells are exposed to irradiation + EF suggests that EF likely inactivate cellular recovering processes. The result for the number of nuclei with gamma

  8. DNA DAMAGE IN BUCCAL EPITHELIAL CELLS FROM INDIVIDUALS CHRONICALLY EXPOSED TO ARSENIC VIA DRINKING WATER IN INNER MONGOLIA, CHINA

    EPA Science Inventory

    The purpose of this pilot study was to assess DNA damage in buccal cells from individuals chronically exposed to arsenic via drinking water in Ba Men, Inner Mongolia. Buccal cells were collected from 19 Ba Men residents exposed to arsenic at 527.5 ? 23.7 g/L (mean ? SEM) and ...

  9. DNA DAMAGE IN BUCCAL EPITHELIAL CELLS FROM INDIVIDUALS CHRONICALLY EXPOSED TO ARSENIC VIA DRINKING WATER IN INNER MONGOLIA, CHINA

    EPA Science Inventory

    The purpose of this pilot study was to assess DNA damage in buccal cells from individuals chronically exposed to arsenic via drinking water in Ba Men, Inner Mongolia. Buccal cells were collected from 19 Ba Men residents exposed to arsenic at 527.5 ? 23.7 g/L (mean ? SEM) and ...

  10. Structural and function changes in organelles of liver cells in rats exposed to magnetic fields

    SciTech Connect

    Gorczynska, E. ); Wegrzynowicz, R. )

    1991-08-01

    Exposure of rats to magnetic fields of 10{sup {minus}3} and 10{sup {minus}2} T for 1 hr daily generated structural changes in hepatocytes mitochondria, endoplasmic reticulum, and ribosomes. Simultaneously there was an increase in the activities of the mitochondrial respiratory enzymes: NADH dehydrogenase, succinic dehydrogenase, and cytochrome oxidase. The extent of the changes in liver cell properties following exposure depend on the duration of exposure to and the strength of the applied magnetic fields. Ultrastructural studies did not reveal any changes in external membranes of hepatocytes or in the membranes of cell nuclei. An increase in the amount of glycogen in hepatocytes of rats exposed to both 10{sup {minus}3} and 10{sup {minus}2} T was noted. The high level of cortisol in serum of exposed rats suggests that magnetic field may be a stress generating factor.

  11. Noise induced calcium oscillations in a cell exposed to electromagnetic fields.

    PubMed

    Zhang, Yuhong; Zhao, Yongli; Chen, Yafei; Yuan, Changqing; Zhan, Yong

    2015-01-01

    The effects of noise on the calcium oscillations in a cell exposed to electromagnetic fields are described by a dynamic model. Noise is a very important factor to be considered in the dynamic research on the calcium oscillations in a cell exposed to electromagnetic fields. Some meaningful results have been obtained here based on the discussion. The results show that the pattern of intracellular calcium oscillations exposure to electromagnetic fields can be influenced by noise. Furthermore, the intracellular calcium oscillations exposure to electromagnetic fields can also be induced by noise. And the work has also studied the relationships between the voltage sensitive calcium channel's open probability and electromagnetic field. The result can provide new insights into constructive roles and potential applications of selecting appropriate electromagnetic field frequency during the research of biological effect of electromagnetic field.

  12. DNA methylation changes in human lung epithelia cells exposed to multi-walled carbon nanotubes.

    PubMed

    Sierra, Marta I; Rubio, Laura; Bayón, Gustavo F; Cobo, Isabel; Menendez, Pablo; Morales, Paula; Mangas, Cristina; Urdinguio, Rocio G; Lopez, Virginia; Valdes, Adolfo; Vales, Gerard; Marcos, Ricard; Torrecillas, Ramon; Fernández, Agustin F; Fraga, Mario F

    2017-09-13

    Humans are increasingly exposed to nanoparticles and, although many of their physiological effects have been described, the molecular mechanisms underlying them are still largely unknown. The present study aimed to determine the possible role of certain epigenetic mechanisms in the cellular response of human lung epithelial cells that are triggered by long-term exposure to titanium dioxide nanoparticles (TiO2NPs) and multi-walled carbon nanotubes (MWCNTs). The results showed that exposure to TiO2NPs had only minor effects on genome-wide DNA methylation. However, we identified 755 CpG sites showing consistent DNA hypomethylation in cells exposed to MWCNTs. These sites were mainly located at low density CpG regions and enhancers, and very frequently on the X chromosome. Our results thus suggest that long-term MWCNT exposure may have important effects on the epigenome.

  13. Mutagenicity and genotoxicity in gill erythrocyte cells of Poecilia reticulata exposed to a glyphosate formulation.

    PubMed

    De Souza Filho, José; Sousa, Caio César Neves; Da Silva, Cláudio Carlos; De Sabóia-Morais, Simone Maria Teixeira; Grisolia, Cesar Koppe

    2013-11-01

    Poecilia reticulata were exposed to herbicide Roundup Transorb(®) for micronucleus test, nuclear abnormalities and comet assay. The exposure-concentrations were based on CL50-96 h following 0, 1.41, 2.83, 4.24 and 5.65 μL L(-1) for 24 h. Micronucleus and comets were significantly increased in the gill erythrocyte cells after herbicide exposure compared with the non-exposed group. Results showed a gradual increase in the number of damaged cells, indicating a concentration-dependent effect and that this herbicide was mutagenic and genotoxic to P. reticulata and this effect could be attributed to a combination of compounds contained in the formulation with the active ingredient glyphosate.

  14. DNA damage in leukocytes, buccal cells and nasal epithelial cells of individuals exposed to air pollution in Mexico City

    SciTech Connect

    Valverde, M.; Lopez, M.C.; Ostrosky-Wegman, P.

    1997-10-01

    There is an increased interest in using biological markers to monitor populations for the identification of exposure to environmental toxicants. Test systems which permit the sensitive detection of DNA damage and DNA repair are critically important. The single cell gel electrophoresis assay is a rapid and a sensitive method for the evaluation of DNA damage at the single cell level ant it provides information on the occurrence of DNA single-strand breaks and alkali labile sites using alkaline conditions. In this work, the differences in the basal level of DNA single strand breaks using alkaline single strand breaks using alkaline single cell gel electrophoresis, between young adults from the south (exposed principally to high levels of ozone) and north (exposed principally to hydrocarbons and particles) of Mexico City was investigated using three different cell types (leukocytes, nasal and buccal epithelial cells). We found an increased DNA tail length in blood and nasal cells from individuals who live in the south part of the city compared to the northern part. However, no differences were observed in buccal epithelial cells. These results show the feasibility of using SCGE in different tissues and its great potential for the monitoring of humans exposed to xenobiotics.

  15. Overproduction of free radical species in embryonal cells exposed to low intensity radiofrequency radiation.

    PubMed

    Burlaka, A; Tsybulin, O; Sidorik, E; Lukin, S; Polishuk, V; Tsehmistrenko, S; Yakymenko, I

    2013-09-01

    Long-term exposure of humans to low intensity radiofrequency electromagnetic radiation (RF-EMR) leads to a statistically significant increase in tumor incidence. Mechanisms of such the effects are unclear, but features of oxidative stress in living cells under RF-EMR exposure were previously reported. Our study aims to assess a production of initial free radical species, which lead to oxidative stress in the cell. Embryos of Japanese quails were exposed in ovo to extremely low intensity RF-EMR of GSM 900 MHz (0.25 µW/cm2) during 158-360 h discontinuously (48 c - ON, 12 c - OFF) before and in the initial stages of development. The levels of superoxide (O2·-), nitrogen oxide (NO·), thiobarbituric acid reactive substances (TBARS), 8-oxo-2'-deoxyguanosine (8-oxo-dG) and antioxidant enzymes' activities were assessed in cells/tissues of 38-h, 5- and 10-day RF-EMR exposed and unexposed embryos. The exposure resulted in a significant persistent overproduction of superoxide and nitrogen oxide in embryo cells during all period of analyses. As a result, significantly increased levels of TBARS and 8-oxo-dG followed by significantly decreased levels of superoxide dismutase and catalase activities were developed in the exposed embryo cells. Exposure of developing quail embryos to extremely low intensity RF-EMR of GSM 900 MHz during at least one hundred and fifty-eight hours leads to a significant overproduction of free radicals/reactive oxygen species and oxidative damage of DNA in embryo cells. These oxidative changes may lead to pathologies up to oncogenic transformation of cells.

  16. Phospholipidomic Profile Variation on THP-1 Cells Exposed to Skin or Respiratory Sensitizers and Respiratory Irritant.

    PubMed

    Martins, João D; Maciel, Elisabete A; Silva, Ana; Ferreira, Isabel; Ricardo, Fernando; Domingues, Pedro; Neves, Bruno M; Domingues, Maria Rosário M; Cruz, Maria Teresa

    2016-12-01

    Occupational exposure to low molecular weight reactive chemicals often leads to development of allergic reactions such as allergic contact dermatitis and respiratory allergies. Further insights into the interaction of these chemicals with physiopathological relevant cellular models might provide the foundations for novel non-animal approaches to safety assessment. In this work we used the human THP-1 cell line to determine phospholipidome changes induced by the skin sensitizer 1-fluoro-2,4-dinitrobenzene (DNFB), the respiratory allergen hexamethylene diisocyanate (HDI), and the irritant methyl salicylate (MESA). We detected that these chemicals differently induce lipid peroxidation and modulate THP-1 IL-1β, IL-12B, IL-8, CD86, and HMOX1 transcription. Decreased phosphatidylethanolamine content was detected in cells exposed to MESA, while profound alterations in the relative abundance of cardiolipin species were observed in cells exposed to DNFB. All chemicals tested induced a decrease in the relative abundance of plasmanyl phosphatidylcholine species PC (O-16:0e/18:1) and phosphatidylinositol species PI (34:1), while increasing PI (38:4). An increased abundance of oleic acid was observed in the phospholipids of cells exposed to DNFB while a decreased abundance of palmitic acid was detected in cells treated with MESA or DNFB. We conclude that both specific and common alterations at phospholipidome levels are triggered by the different chemicals, while not allowing a complete distinction between them using a Canonical Analysis of Principal Coordinates (CAP). The common effects observed at phospholipids level with all the chemicals tested might be related to unspecific cell cytotoxic mechanisms that nevertheless may contribute to the elicitation of specific immune responses. J. Cell. Physiol. 231: 2639-2651, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  17. Apoptosis and necroptosis are induced in rainbow trout cell lines exposed to cadmium.

    PubMed

    Krumschnabel, Gerhard; Ebner, Hannes L; Hess, Michael W; Villunger, Andreas

    2010-08-01

    Cadmium is an important environmental toxicant that can kill cells. A number of studies have implicated apoptosis as well as necrosis and, most recently, a form of programmed necrosis termed necroptosis in the process of cadmium-mediated toxicity, but the exact mechanism remains ill-defined and may depend on the affected cell type. This study investigated which mode of cell death may be responsible for cell death induction in cadmium-exposed trout cell lines from gill and liver and if this cell death was sensitive to inhibitors of necroptosis or apoptosis, respectively. It was observed that intermediate levels of cadmium that killed approximately 50% of the cells over 96-120h of exposure caused cell death that morphologically resembled apoptosis and was associated with an increase of apoptotic markers such as the number of cells with diminished DNA content (sub-G1 cells), condensed or fragmented nuclei, and elevation of caspase-3 activity. At the same time, however, cells also lost plasma membrane integrity, as indicated by uptake of propidium iodide, showed a decrease of ATP levels and mitochondrial membrane potential, and displayed cell swelling, signs associated with secondary necrosis, or equally possible, necroptotic cell death. Importantly, many of these alterations were at least partly inhibited by the necroptosis inhibitor necrostatin-1 and were to a lesser extent also sensitive to the pan-caspase inhibitor zVAD-fmk, indicating that multiple modes of cell death are concurrently induced in cadmium-exposed trout cells, including necroptosis and apoptosis. Cell death appeared to lack concurrent radical formation, consistent with genetically regulated necroptotic cell death, but was characterized by the rapid induction of DNA damage markers, and the early onset of disintegration of the Golgi complex. Comparative experiments evaluating copper-toxicity indicated that in comparison to cadmium much higher concentrations of this metal were required to induce cell

  18. BCG vaccination induces HIV target cell activation in HIV-exposed infants in a randomized trial

    PubMed Central

    Gasper, Melanie A.; Hesseling, Anneke C.; Mohar, Isaac; Myer, Landon; Azenkot, Tali; Passmore, Jo-Ann S.; Hanekom, Willem; Cotton, Mark F.; Crispe, I. Nicholas; Sodora, Donald L.; Jaspan, Heather B.

    2017-01-01

    BACKGROUND. Bacillus Calmette-Guérin (BCG) vaccine is administered at birth to protect infants against tuberculosis throughout Africa, where most perinatal HIV-1 transmission occurs. We examined whether BCG vaccination alters the levels of activated HIV target T cells in HIV-exposed South African infants. METHODS. HIV-exposed infants were randomized to receive routine (at birth) or delayed (at 8 weeks) BCG vaccination. Activated and CCR5-expressing peripheral blood CD4+ T cell, monocyte, and NK cell frequencies were evaluated by flow cytometry and immune gene expression via PCR using Biomark (Fluidigm). RESULTS. Of 149 infants randomized, 92% (n = 137) were retained at 6 weeks: 71 in the routine BCG arm and 66 in the delayed arm. Routine BCG vaccination led to a 3-fold increase in systemic activation of HIV target CD4+CCR5+ T cells (HLA-DR+CD38+) at 6 weeks (0.25% at birth versus 0.08% in delayed vaccination groups; P = 0.029), which persisted until 8 weeks of age when the delayed arm was vaccinated. Vaccination of the infants in the delayed arm at 8 weeks resulted in a similar increase in activated CD4+CCR5+ T cells. The increase in activated T cells was associated with increased levels of MHC class II transactivator (CIITA), IL12RB1, and IFN-α1 transcripts within peripheral blood mononuclear cells but minimal changes in innate cells. CONCLUSION. BCG vaccination induces immune changes in HIV-exposed infants, including an increase in the proportion of activated CCR5+CD4+ HIV target cells. These findings provide insight into optimal BCG vaccine timing to minimize the risks of HIV transmissions to exposed infants while preserving potential benefits conferred by BCG vaccination. TRIAL REGISTRATION. ClinicalTrials.gov NCT02062580. FUNDING. This trial was sponsored by the Elizabeth Glaser Pediatric AIDS Foundation (MV-00-9-900-01871-0-00) and the Thrasher Foundation (NR-0095); for details, see Acknowledgments. PMID:28405623

  19. Reduced cytotoxicity in PCB-exposed Chinese Hamster Ovary (CHO) cells pretreated with vitamin E.

    PubMed

    Murati, Teuta; Šimić, Branimir; Pleadin, Jelka; Vukmirović, Maja; Miletić, Marina; Durgo, Ksenija; Kniewald, Jasna; Kmetič, Ivana

    2017-01-01

    The aim of this study was to evaluate protective effects of vitamin E (50 -150 μM) in ovary cells upon cytotoxic effects induced by two structurally distinct PCB congeners - planar "dioxin-like" PCB 77 and non-planar di-ortho-substituted PCB 153 with an emphasis on identifying differences in the mechanism of vitamin E action depending on the structure of congeners. Application of three bioassays confirmed that PCBs decrease ovarian cell proliferation with slightly profound effects of PCB 77. PCB - induced ROS production and lipid peroxidation were significant for both congeners with also more noticeable effect for PCB 77. Vitamin E pre-incubation has improved viability of cells, reduced ROS formation and lipid peroxidation induced by PCBs' treatment. Preincubation with vitamin E was more effective when cells where treated with non-planar PCB 153. Altogether, vitamin E action was protective, congener specific and more effective when ovary cells were exposed to ortho-substituted PCB congener.

  20. Thyroid hormone suppression and cell-mediated immunomodulation in American kestrels (Falco sparverius) exposed to PCBs.

    PubMed

    Smits, J E; Fernie, K J; Bortolotti, G R; Marchant, T A

    2002-10-01

    Exposure to environmental contaminants can induce physiological changes in animals through various mechanisms. One manifestation of subclinical toxicity from polychlorinated biphenyl (PCB) exposure is the disruption of normal immune function described in numerous species, including American kestrels (Falco sparverius). In 1998, 152 mature male and female kestrels were fed either a mixture of Aroclor 1248:1254:1260 (approximately 7 mg/kg kestrel/day) through their food items, or control diets. Offspring produced by 50 breeding pairs (thus, half received in ovo PCB exposure only) were also studied. Total and differential white blood cell counts, the phytohemagglutinin (PHA) skin response, as well as thyroid hormone levels were tested in vivo in nonbreeding adults (1998 only) and nestlings (1998 and 1999). In 1999, nestlings came from three parental groups; adults exposed in 1998, birds produced by PCB-exposed parents, and unexposed birds. In 1998, directly exposed males but not females had increased total white blood cell counts driven by lymphocytosis, plus a decreased heterophil-to-lymphocyte ratio relative to controls. PCB-exposed birds had a significantly greater response to PHA than did controls, with sex as a significant factor and plasma triiodothyonine (T(3)) as a significant covariate. Levels of T(3) were significantly depressed in PCB-exposed birds of both sexes. The 1999 nestlings (F1 generation with respect to PCB exposure) did not show any effect of parental treatment group on the PHA skin response, yet T(3) remained as a significant covariate. Immunological effects are discussed in light of the antibody-mediated immunotoxicity found in the same birds and reported previously.

  1. Mechanisms of mutagenesis in human cells exposed to 55 MeV protons

    NASA Technical Reports Server (NTRS)

    Gauny, S.; Wiese, C.; Kronenberg, A.

    2001-01-01

    Protons represent the major type of charged particle radiation in spaceflight environments. The purpose of this study was to assess mutations arising in human lymphoid cells exposed to protons. Mutations were quantitated at the thymidine kinase (TK1) locus in cell lines derived from the same donor: TK6 cells (wt TP53) and WTK1 cells (mutant TP53). WTK1 cells were much more susceptible to mutagenesis following proton exposure than TK6 cells. Intragenic deletions were observed among early-arising TK1 mutants in TK6 cells, but not in WTK1 cells where all of the mutants arose by LOH. Deletion was the predominant mode of LOH in TK6 cells, while allelic recombination was the major mode of LOH in WTK1 cells. Deletions were of variable lengths, from <1 cM to 64 cM, while mutations that arose by allelic recombination often extended to the telomere. In summary, proton exposures elicited many types of mutations at an autosomal locus in human cells. Most involved large scale loss of genetic information, either through deletion or by recombination.

  2. Adrenal chromaffin cells do not swell when exposed to nanosecond electric pulses.

    PubMed

    Craviso, Gale L; Fisher, Christa; Chatterjee, Indira; Vernier, P Thomas

    2015-06-01

    High intensity, nanosecond duration electric pulses (NEPs) permeabilize plasma membranes causing osmotic cell swelling that can elicit a wide variety of cellular effects. This study examined the possibility that cell swelling is the mechanism by which 5 ns NEPs trigger the release of catecholamines from neuroendocrine adrenal chromaffin cells. Swelling was assessed by comparing measurements of cell area obtained from bright field images of the cells before and at 10s intervals following exposure of the cells to 5 ns pulses at a field intensity of 5-6 MV/m. The results indicated that chromaffin cells do not swell in response to a single pulse or a train of ten pulses delivered at repetition frequencies of 10 Hz and 1 kHz. Swelling was also not observed in response to a train of 50 pulses whereas Jurkat T lymphoblast cell area increased 15% on average under the same NEP exposure conditions. These results demonstrating that chromaffin cells do not undergo swelling when exposed to 5 ns NEPs have important implications regarding the mechanism by which these pulses stimulate the release of catecholamines from these cells, namely that catecholamine secretion is most likely not caused by cell swelling.

  3. Bicalutamide inhibits androgen-mediated adhesion of prostate cancer cells exposed to ionizing radiation

    PubMed Central

    Wang, Tao; Alavian, Michael R.; Goel, Hira Lal; Languino, Lucia R.; FitzGerald, Thomas J.

    2009-01-01

    Background Cell adhesion plays an important role in proliferation, metastasis, and tumor growth and may represent a potential vulnerability in treatment of prostate cancer patients. Bicalutamide (Casodex) has been used as an anti-androgen agent for prostate cancer patients during hormone ablation therapy. This study focuses on the effect of Bicalutamide on cell adhesion to fibronectin in prostate cancer cells. Methods LNCaP prostate cancer cells were stimulated with androgen before being irradiated with doses of 0, 5, 10 or 15 Gy. Cell adhesion to fibronectin was then measured to ascertain androgen's role in integrin mediated prostate cancer cell adhesion. Flow cytometry was used to analyze surface expression of integrin subtypes in LNCaP cells upon androgen stimulation and 15 Gy ionizing radiation. Results LNCaP cell adhesion to fibronectin (FN) was significantly increased by stimulation with androgen when treated with 10 or 15 Gy ionizing radiations but not at 0 or 5 Gy. This increase was inhibited by treatment with Bicalutamide. LNCaP cells exposed to high dose radiation showed an increased expression of αV and β1 integrins in response to androgen treatment while Bicalutamide abolished this effect. Conclusions Our data show that Bicalutamide inhibits the effect of androgen on cell adhesion to FN through changes of integrin subtypes in androgen-dependent prostate cancer cells given high dose radiation. This suggests new molecular targets and possible treatment strategies for prostate cancer patients to improve the outcome during hormone ablation therapy and radiation therapy. PMID:18729104

  4. Mechanisms of mutagenesis in human cells exposed to 55 MeV protons

    NASA Technical Reports Server (NTRS)

    Gauny, S.; Wiese, C.; Kronenberg, A.

    2001-01-01

    Protons represent the major type of charged particle radiation in spaceflight environments. The purpose of this study was to assess mutations arising in human lymphoid cells exposed to protons. Mutations were quantitated at the thymidine kinase (TK1) locus in cell lines derived from the same donor: TK6 cells (wt TP53) and WTK1 cells (mutant TP53). WTK1 cells were much more susceptible to mutagenesis following proton exposure than TK6 cells. Intragenic deletions were observed among early-arising TK1 mutants in TK6 cells, but not in WTK1 cells where all of the mutants arose by LOH. Deletion was the predominant mode of LOH in TK6 cells, while allelic recombination was the major mode of LOH in WTK1 cells. Deletions were of variable lengths, from <1 cM to 64 cM, while mutations that arose by allelic recombination often extended to the telomere. In summary, proton exposures elicited many types of mutations at an autosomal locus in human cells. Most involved large scale loss of genetic information, either through deletion or by recombination.

  5. Immune recognition of exposed xenoantigens on the surface of PEGylated bovine red blood cells.

    PubMed

    Gundersen, Sharon I; Kennedy, Melanie S; Palmer, Andre F

    2008-10-01

    Due to potential problems that can occur during blood transfusion and increasing blood shortages, our group engineered methoxypolyethylene glycol conjugated bovine red blood cells (mPEG-bRBCs) as a potential universal oxygen therapeutic. This current work investigates the immunological properties of mPEG-bRBCs incubated with human plasma (hP) and correlates these properties to exposed Galalpha(1,3)Gal xenoantigens. After mPEG-bRBCs were incubated with hP, the amount of bound IgG and IgM was assessed via flow cytometry. Flow cytometry also assessed the amount of GS-IB4 bound to exposed Galalpha(1,3)Gal xenoantigens. The results of this study demonstrate that most hP samples strongly promote agglutination of mPEG-bRBCs regardless of the extent of mPEG surface coverage or donor blood type. IgG and IgM from hP bound strongly to mPEG-bRBCs. In general, the Galalpha(1,3)Gal xenoantigen remains exposed at all levels of PEG surface coverage. PEGylation did block some of the xenoantigens as the amount of exposed Galalpha (1,3)Gal decreased with increased mPEG surface coverage. However, this was not sufficient to prevent a strong agglutination reaction. Taken together, the results of this study indicate that the current strategy for PEGylating bRBCs is unsatisfactory for the development of immunologically silent oxygen therapeutics.

  6. Ceftaroline modulates the innate immune and host defense responses of immunocompetent cells exposed to cigarette smoke.

    PubMed

    Bruno, A; Cipollina, C; Di Vincenzo, S; Siena, L; Dino, P; Di Gaudio, F; Gjomarkaj, M; Pace, E

    2017-09-05

    Cigarette smoke, the principal risk factor for chronic obstructive pulmonary disease (COPD), negatively influences the effectiveness of the immune system's response to a pathogen. The antibiotic ceftaroline exerts immune-modulatory effects in bronchial epithelial cells exposed to cigarette smoke. The present study aims to assess the effects of ceftaroline on TLR2 and TLR4 expression, LPS binding and TNF-α and human beta defensin (HBD2) release in an undifferentiated and PMA-differentiated human monocyte cell line (THP-1) exposed or not to cigarette smoke extracts (CSE). TLR2, TLR4, and LPS binding were assessed by flow cytometry, TNF-α and HBD2 release were evaluated by ELISA. The constitutive expression of TLR2 and TLR4 and LPS binding were higher in differentiated compared to undifferentiated THP-1 cells. In undifferentiated THP-1 cells, CSE increased TLR2 and TLR4 protein levels, LPS binding and TNF-α release and reduced HBD2 release and ceftaroline counteracted all these effects. In differentiated THP-1, CSE did not significantly affect TLR2 and TLR4 expression and LPS binding but reduced HBD2 release and increased TNF-α release. Ceftaroline counteracted the effects of CSE on HBD2 release in differentiated THP-1. Ceftaroline counteracts the effect of CSE in immune cells by increasing the effectiveness of the innate immune system. This effect may also assist in reducing pathogen activity and recurrent exacerbations in COPD patients. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Identification of gene-based responses in human blood cells exposed to alpha particle radiation

    PubMed Central

    2014-01-01

    Background The threat of a terrorist-precipitated nuclear event places humans at danger for radiological exposures. Isotopes which emit alpha (α)-particle radiation pose the highest risk. Currently, gene expression signatures are being developed for radiation biodosimetry and triage with respect to ionizing photon radiation. This study was designed to determine if similar gene expression profiles are obtained after exposures involving α-particles. Methods Peripheral blood mononuclear cells (PBMCs) were used to identify sensitive and robust gene-based biomarkers of α-particle radiation exposure. Cells were isolated from healthy individuals and were irradiated at doses ranging from 0-1.5 Gy. Microarray technology was employed to identify transcripts that were differentially expressed relative to unirradiated cells 24 hours post-exposure. Statistical analysis identified modulated genes at each of the individual doses. Results Twenty-nine genes were common to all doses with expression levels ranging from 2-10 fold relative to control treatment group. This subset of genes was further assessed in independent complete white blood cell (WBC) populations exposed to either α-particles or X-rays using quantitative real-time PCR. This 29 gene panel was responsive in the α-particle exposed WBCs and was shown to exhibit differential fold-changes compared to X-irradiated cells, though no α-particle specific transcripts were identified. Conclusion Current gene panels for photon radiation may also be applicable for use in α-particle radiation biodosimetry. PMID:25017500

  8. Effects of selenocystine on lead-exposed Chinese hamster ovary (CHO) and PC-12 cells

    SciTech Connect

    Aykin-Burns, Nukhet; Ercal, Nuran . E-mail: nercal@umr.edu

    2006-07-15

    Lead is a pervasive environmental toxin that affects multiple organ systems, including the nervous, renal, reproductive, and hematological systems. Even though it is probably the most studied toxic metal, some of the symptoms of lead toxicity still cannot be explained by known molecular mechanisms. Therefore, lead-induced oxidative stress has recently started to gain attention. This in vitro study confirms the existence of oxidative stress due to lead exposure. Administration of lead acetate (PbA) to cultures of Chinese hamster ovary cells (CHO) had a concentration-dependent inhibitory effect on colony formation and cell proliferation. This inhibition was eliminated by 5 {mu}M selenocystine (SeCys). In order to evaluate the nature of SeCys's effect, we measured glutathione (GSH), its oxidized form glutathione disulfide (GSSG), malondialdehyde (MDA), catalase, and GSH peroxidase (GPx) activities in lead-exposed CHO cells both in the presence and absence of SeCys. Increases in MDA, catalase, and GPx activities were observed in cultures that received only PbA, but supplementation with SeCys returned these measures to pretreatment levels. The ratio of GSH to GSSG increased in lead-exposed cells incubated in SeCys-enhanced media but declined in cultures treated with PbA only. In order to determine whether SeCys also reverses lead-induced neurotoxicity, a neuronal cell line, PC-12 cells, was used. Lead's inhibition on neurite formation was significantly eliminated by SeCys in PC-12 cells. Our results suggest that SeCys can confer protection against lead-induced toxicity in CHO cells and neurotoxicity in PC-12 cells.

  9. Assessment of DNA integrity (COMET assay) in sperm cells of boron-exposed workers.

    PubMed

    Duydu, Yalçin; Başaran, Nurşen; Ustündağ, Aylin; Aydin, Sevtap; Undeğer, Ulkü; Ataman, Osman Yavuz; Aydos, Kaan; Düker, Yalçin; Ickstadt, Katja; Waltrup, Britta Schulze; Golka, Klaus; Bolt, Hermann M

    2012-01-01

    An extension of a male reproductive study conducted in a boric acid/borate production zone at Bandırma, Turkey, is presented. The relation between DNA-strand breaks (COMET assay, neutral and alkaline version) in sperm cells and previously described sperm quality parameters was investigated in boron-exposed males. A correlation between blood boron levels and mean DNA-strand breaks in sperm was weak, and DNA-strand breaks in sperm were statistically not different between control and exposed groups. Therefore, increasing boron exposures had no additional contribution in addition to already pre-existing DNA-strand breaks in the sperm cells. Weak but statistically significant correlations between DNA-strand breaks and motility/morphology parameters of sperm samples were observed in the neutral version of the COMET assay, while correlations between the same variables were statistically not significant in the alkaline version. A likely reason for these negative results, even in highly exposed humans, is that experimental exposures that had led to reproductive toxicity in animals were significantly higher than any boron exposures, which may be reached under realistic human conditions.

  10. Sirolimus Increases T-Cell Abundance in the Sun Exposed Skin of Kidney Transplant Recipients

    PubMed Central

    Burke, Michael Thomas; Sambira Nahum, Lauren C.; Isbel, Nicole M.; Carroll, Robert P.; Soyer, Hans Peter; Francis, Ross; Bridge, Jennifer Anne; Hawley, Carmel; Oliver, Kimberly; Staatz, Christine E.; Wells, James William

    2017-01-01

    Background Kidney transplant recipients (KTRs) receiving the mammalian target of rapamycin inhibitor sirolimus may display a reduced risk of skin cancer development compared to KTRs receiving calcineurin inhibitors. Despite studies investigating the effects of these 2 drug classes on T cells in patient blood, the effect these drugs may have in patient skin is not yet known. Methods Fifteen patients with chronic kidney disease (not recipients of immunosuppressive drugs), and 30 KTRs (15 receiving a calcineurin inhibitor, and 15 receiving sirolimus) provided matched samples of blood, sun exposed (SE) and non-SE skin. The abundance of total CD8+ and CD4+ T cells, memory CD8+ and CD4+ T cells, and regulatory T (Treg) cells in each sample was then assessed by flow cytometry. Results Sirolimus treatment significantly increased absolute numbers of CD4+ T cells, memory CD8+- and CD4+ T cells, and Treg cells in SE skin versus paired samples of non-SE skin. No differences were found in the absolute number of any T cell subset in the blood. Correlation analysis revealed that the percentage of T cell subsets in the blood does not always accurately reflect the percentage of T-cell subsets in the skin of KTRs. Furthermore, sirolimus significantly disrupts the balance of memory CD4+ T cells in the skin after chronic sun exposure. Conclusions This study demonstrated that immunosuppressive drug class and sun exposure modify the abundance of multiple T-cell subsets in the skin of KTRs. Correlation analysis revealed that the prevalence of Treg cells in KTR blood does not accurately reflect the prevalence of Treg cells in KTR skin. PMID:28706974

  11. Dose- and Time-Dependent Transcriptional Response of Ishikawa Cells Exposed to Genistein.

    PubMed

    Naciff, Jorge M; Khambatta, Zubin S; Carr, Gregory J; Tiesman, Jay P; Singleton, David W; Khan, Sohaib A; Daston, George P

    2016-05-01

    To further define the utility of the Ishikawa cells as a reliable in vitro model to determine the potential estrogenic activity of chemicals of interest, transcriptional changes induced by genistein (GES) in Ishikawa cells at various doses (10 pM, 1 nM, 100 nM, and 10 μM) and time points (8, 24, and 48 h) were identified using a comprehensive microarray approach. Trend analysis indicated that the expression of 5342 unique genes was modified by GES in a dose- and time-dependent manner (P ≤ 0.0001). However, the majority of gene expression changes induced in Ishikawa cells were elicited by the highest dose of GES evaluated (10 μM). The GES' estrogenic activity was identified by comparing the Ishikawa cells' response to GES versus 17 α-ethynyl estradiol (EE, at equipotent doses, ie, 10 μM vs 1 μM, respectively) and was defined by changes in the expression of 284 unique genes elicited by GES and EE in the same direction, although the magnitude of the change for some genes was different. Further, comparing the response of the Ishikawa cells exposed to high doses of GES and EE versus the response of the juvenile rat uterus exposed to EE, we identified 66 unique genes which were up- or down regulated in a similar manner in vivo as well as in vitro Genistein elicits changes in multiple molecular pathways affecting various biological processes particularly associated with cell organization and biogenesis, regulation of translation, cell proliferation, and intracellular transport; processes also affected by estrogen exposure in the uterus of the rat. These results indicate that Ishikawa cells are capable of generating a biologically relevant estrogenic response and offer an in vitro model to assess this mode of action.

  12. Chromosomal Aberrations in Normal and AT Cells Exposed to High Dose of Low Dose Rate Irradiation

    NASA Technical Reports Server (NTRS)

    Kawata, T.; Shigematsu, N.; Kawaguchi, O.; Liu, C.; Furusawa, Y.; Hirayama, R.; George, K.; Cucinotta, F.

    2011-01-01

    Ataxia telangiectasia (A-T) is a human autosomally recessive syndrome characterized by cerebellar ataxia, telangiectases, immune dysfunction, and genomic instability, and high rate of cancer incidence. A-T cell lines are abnormally sensitive to agents that induce DNA double strand breaks, including ionizing radiation. The diverse clinical features in individuals affected by A-T and the complex cellular phenotypes are all linked to the functional inactivation of a single gene (AT mutated). It is well known that cells deficient in ATM show increased yields of both simple and complex chromosomal aberrations after high-dose-rate irradiation, but, less is known on how cells respond to low-dose-rate irradiation. It has been shown that AT cells contain a large number of unrejoined breaks after both low-dose-rate irradiation and high-dose-rate irradiation, however sensitivity for chromosomal aberrations at low-dose-rate are less often studied. To study how AT cells respond to low-dose-rate irradiation, we exposed confluent normal and AT fibroblast cells to up to 3 Gy of gamma-irradiation at a dose rate of 0.5 Gy/day and analyzed chromosomal aberrations in G0 using fusion PCC (Premature Chromosomal Condensation) technique. Giemsa staining showed that 1 Gy induces around 0.36 unrejoined fragments per cell in normal cells and around 1.35 fragments in AT cells, whereas 3Gy induces around 0.65 fragments in normal cells and around 3.3 fragments in AT cells. This result indicates that AT cells can rejoin breaks less effectively in G0 phase of the cell cycle? compared to normal cells. We also analyzed chromosomal exchanges in normal and AT cells after exposure to 3 Gy of low-dose-rate rays using a combination of G0 PCC and FISH techniques. Misrejoining was detected in the AT cells only? When cells irradiated with 3 Gy were subcultured and G2 chromosomal aberrations were analyzed using calyculin-A induced PCC technique, the yield of unrejoined breaks decreased in both normal and AT

  13. Endothelial dysfunction and monocyte recruitment in cells exposed to non-uniform shear stress.

    PubMed

    Cicha, Iwona; Goppelt-Struebe, Margarete; Yilmaz, Atilla; Daniel, Werner G; Garlichs, Christoph D

    2008-01-01

    Atherosclerosis results from a combination of local blood flow patterns and systemic risk factors. We investigated whether non-uniform shear stress at bifurcations induces pro-atherogenic endothelial dysfunction and monocyte recruitment. Bifurcating flow-through cell culture slides were used to expose HUVECs to laminar or non-uniform shear stress for 18 h at 10 dyne/cm(2). For the adhesion assay, HUVECs were subsequently perfused with medium containing THP-1 monocytes for 1 h. Protein expression was determined by immunofluorescence. In areas exposed to laminar shear stress, alignment of endothelial cells with the flow was observed, accompanied by upregulation of eNOS and downregulation of connective tissue growth factor (CTGF). In contrast, cells exposed to non-uniform shear stress near the outer walls of bifurcations were characterized by irregular, unaligned shape, induction of endothelin-1 and CTGF, as well as reduced eNOS expression. These atherogenic effects of non-uniform shear stress were prevented when cells were treated with statins (1 mumol/l) during flow. Under non-uniform shear stress, a slight induction of VCAM-1, ICAM-1, and E-/P-selectin was observed. In agreement with this, monocyte recruitment, which was nearly undetectable under laminar shear stress, was moderately induced by non-uniform shear stress (P<0.02). In conclusion, inhibition of antioxidative eNOS and upregulation of atherogenic proteins is the first step in non-uniform shear stress-mediated endothelial dysfunction, which in vivo in the presence of atherogenic risk factors may further enhance monocyte recruitment into the artery wall.

  14. Cytoprotective effect of lacritin on human corneal epithelial cells exposed to benzalkonium chloride in vitro

    PubMed Central

    Feng, Mary M.; Baryla, Julia; Liu, Hong; Laurie, Gordon W.; McKown, Robert L.; Ashki, Negin; Bhayana, Dinesh

    2015-01-01

    Purpose Benzalkonium chloride (BAK) is the most commonly found preservative in eye drops, and has been shown to cause ocular surface inflammation and toxicity. Lacritin is a human tear glycoprotein secreted from the lacrimal glands that has been found to be cytoprotective. This study was designed to determine if the presence of lacritin confers protection to a cultured human corneal epithelial (HCE) cell line, CRL-11515, and primary HCE cells after exposure to the ocular preservative agent BAK. Materials and Methods Recombinant human lacritin was cloned into intein fusion vectors, expressed in E. coli, and purified on chitin beads and DEAE Sepharose. Metabolic curves were established using the MTT assay after exposure of subconfluent CRL-11515 cells to BAK or lacritin. Western blot analysis of lipidated LC3 (LC3-II) provided a measure of autophagy in CRL-11515 cells exposed to lacritin and/or BAK. Results BAK reduced CRL-11515 cellular metabolic activity in a time and dose dependent manner. BAK-induced cellular stress was evident by elevated autophagy that increased with rising concentrations of BAK compared to control (P < 0.05). Lacritin increased HCE cell proliferation at an optimal dose of 1 nM. Preconditioning HCE cells with 1 nM lacritin for 24 hours prior to BAK exposure significantly dampened levels of LC3-II (P < 0.05) and promoted a significant increase in cellular metabolic activity (P < 0.01) compared to BAK alone. Conclusions These results suggest lacritin protects cultured HCE cells stressed with BAK. Lacritin may have the potential to be used as a topical adjunctive therapy in eyes chronically exposed to BAK. PMID:24401093

  15. Dose-rate effect on proliferation suppression in human cell lines continuously exposed to γ rays.

    PubMed

    Magae, Junji; Furukawa, Chiharu; Ogata, Hiromitsu

    2011-10-01

    Irradiation time and dose rate are important factors in the evaluation of radiation risk for human health. We previously proposed a novel dose-rate effect model, the modified exponential (MOE) model, which predicts that radiation risks decline exponentially as the dose rate decreases. Here we show that, during the early phase of exposure, up to 1000 h, the proliferation of cells continuously exposed to γ rays at a constant dose rate is gradually suppressed, even as the total dose increases. This trend holds for a number of cell lines including tumor cells, nontransformed fibroblasts and leukocytes. The accumulation of total dose by longer exposure times does not increase this suppressive effect even in cells with a defective DNA repair system, suggesting that risk is determined solely by dose rate in the later phase. The dose-rate effect in the early phase follows the MOE model in DNA repair-proficient cell lines, while cells with impaired DNA-PK or ATM show no dose-rate effect. In the later phase, however, a certain dose-rate effect is observed even in mutant cell lines, and suppression of cell proliferation no longer follows the MOE model. Our results suggest that a distinct mechanism that can operate in the absence of intact DNA-PK or ATM influences the dose-rate effect in the later phase of continuous radiation exposure.

  16. Cytoskeleton Modifications and Autophagy Induction in TCam-2 Seminoma Cells Exposed to Simulated Microgravity

    PubMed Central

    Ferranti, Francesca; Caruso, Maria; Cammarota, Marcella; Fabrizi, Cinzia; Fumagalli, Lorenzo; Schiraldi, Chiara; Catizone, Angela

    2014-01-01

    The study of how mechanical forces may influence cell behavior via cytoskeleton remodeling is a relevant challenge of nowadays that may allow us to define the relationship between mechanics and biochemistry and to address the larger problem of biological complexity. An increasing amount of literature data reported that microgravity condition alters cell architecture as a consequence of cytoskeleton structure modifications. Herein, we are reporting the morphological, cytoskeletal, and behavioral modifications due to the exposition of a seminoma cell line (TCam-2) to simulated microgravity. Even if no differences in cell proliferation and apoptosis were observed after 24 hours of exposure to simulated microgravity, scanning electron microscopy (SEM) analysis revealed that the change of gravity vector significantly affects TCam-2 cell surface morphological appearance. Consistent with this observation, we found that microtubule orientation is altered by microgravity. Moreover, the confocal analysis of actin microfilaments revealed an increase in the cell width induced by the low gravitational force. Microtubules and microfilaments have been related to autophagy modulation and, interestingly, we found a significant autophagic induction in TCam-2 cells exposed to simulated microgravity. This observation is of relevant interest because it shows, for the first time, TCam-2 cell autophagy as a biological response induced by a mechanical stimulus instead of a biochemical one. PMID:25140323

  17. Single Walled Carbon Nanotubes Exhibit Dual-Phase Regulation to Exposed Arabidopsis Mesophyll Cells

    PubMed Central

    2011-01-01

    Herein we are the first to report that single-walled carbon nanotubes (SWCNTs) exhibit dual-phase regulation to Arabidopsis mesophyll cells exposed to different concentration of SWCNTs. The mesophyll protoplasts were prepared by enzyme digestion, and incubated with 15, 25, 50, 100 μg/ml SWCNTs for 48 h, and then were observed by optical microscopy and transmission electron microscopy, the reactive oxygen species (ROS) generation was measured. Partial protoplasts were stained with propidium iodide and 4'-6- diamidino-2-phenylindole, partial protoplasts were incubated with fluorescein isothiocyanate-labeled SWCNTs, and observed by fluorescence microscopy. Results showed that SWCNTs could traverse both the plant cell wall and cell membrane, with less than or equal to 50 μg/ml in the culture medium, SWCNTs stimulated plant cells to grow out trichome clusters on their surface, with more than 50 μg/ml SWCNTs in the culture medium, SWCNTs exhibited obvious toxic effects to the protoplasts such as increasing generation of ROS, inducing changes of protoplast morphology, changing green leaves into yellow, and inducing protoplast cells' necrosis and apoptosis. In conclusion, single walled carbon nanotubes can get through Arabidopsis mesophyll cell wall and membrane, and exhibit dose-dependent dual-phase regulation to Arabidopsis mesophyll protoplasts such as low dose stimulating cell growth, and high dose inducing cells' ROS generation, necrosis or apoptosis. PMID:27502666

  18. Creatine as a compatible osmolyte in muscle cells exposed to hypertonic stress

    PubMed Central

    Alfieri, Roberta R; Bonelli, Mara A; Cavazzoni, Andrea; Brigotti, Maurizio; Fumarola, Claudia; Sestili, Piero; Mozzoni, Paola; De Palma, Giuseppe; Mutti, Antonio; Carnicelli, Domenica; Vacondio, Federica; Silva, Claudia; Borghetti, Angelo F; Wheeler, Kenneth P; Petronini, Pier Giorgio

    2006-01-01

    Exposure of C2C12 muscle cells to hypertonic stress induced an increase in cell content of creatine transporter mRNA and of creatine transport activity, which peaked after about 24 h incubation at 0.45 osmol (kg H2O)−1. This induction of transport activity was prevented by addition of either cycloheximide, to inhibit protein synthesis, or of actinomycin D, to inhibit RNA synthesis. Creatine uptake by these cells is largely Na+ dependent and kinetic analysis revealed that its increase under hypertonic conditions resulted from an increase in Vmax of the Na+-dependent component, with no significant change in the Km value of about 75 μmol l−1. Quantitative real-time PCR revealed a more than threefold increase in the expression of creatine transporter mRNA in cells exposed to hypertonicity. Creatine supplementation significantly enhanced survival of C2C12 cells incubated under hypertonic conditions and its effect was similar to that obtained with the well known compatible osmolytes, betaine, taurine and myo-inositol. This effect seemed not to be linked to the energy status of the C2C12 cells because hypertonic incubation caused a decrease in their ATP content, with or without the addition of creatine at 20 mmol l−1 to the medium. This induction of creatine transport activity by hypertonicity is not confined to muscle cells: a similar induction was shown in porcine endothelial cells. PMID:16873409

  19. Insights on cryoprotectant toxicity from gene expression profiling of endothelial cells exposed to ethylene glycol.

    PubMed

    Cordeiro, Rui Martins; Stirling, Soren; Fahy, Gregory M; de Magalhães, João Pedro

    2015-12-01

    Cryopreservation consists of preserving living cells or tissues generally at -80 °C or below and has many current applications in cell and tissue banking, and future potential for organ banking. Cryoprotective agents such as ethylene glycol (EG) are required for successful cryopreservation of most living systems, but have toxic side effects whose mechanisms remain largely unknown. In this work, we investigated the mechanisms of toxicity of ethylene glycol in human umbilical vein endothelial cells (HUVECs) as a model of the vascular endothelium in perfused organs. Exposing cells to 60% v/v EG for 2 h at 4 °C resulted in only a slight decrease in subsequent cell growth, suggesting only modest toxicity of EG for this cell type. Gene expression analysis with whole genome microarrays revealed signatures indicative of a generalized stress response at 24 h after EG exposure and a trend toward partial recovery at 72 h. The observed changes involved signalling pathways, glycoproteins, and genes involved in extracellular and transmembrane functions, the latter suggesting potential effects of ethylene glycol on membranes. These results continue to develop a new paradigm for understanding cryoprotectant toxicity and reveal molecular signatures helpful for future experiments in more completely elucidating the toxic effects of ethylene glycol in vascular endothelial cells and other cell types. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. Live-cell imaging study of mitochondrial morphology in mammalian cells exposed to X-rays.

    PubMed

    Noguchi, M; Kanari, Y; Yokoya, A; Narita, A; Fujii, K

    2015-09-01

    Morphological changes in mitochondria induced by X-irradiation in normal murine mammary gland cells were studied with a live-cell microscopic imaging technique. Mitochondria were visualised by staining with a specific fluorescent probe in the cells, which express fluorescent ubiquitination-based cell-cycle indicator 2 (Fucci2) probes to visualise cell cycle. In unirradiated cells, the number of cells with fragmented mitochondria was about 20 % of the total cells through observation period (96 h). In irradiated cells, the population with fragmented mitochondria significantly increased depending on the absorbed dose. Particularly, for 8 Gy irradiation, the accumulation of fragmentation persists even in the cells whose cell cycle came to a stand (80 % in G1 (G0-like) phase). The fraction reached to a maximum at 96 h after irradiation. The kinetics of the fraction with fragmented mitochondria was similar to that for cells in S/G2/M phase (20 %) through the observation period (120 h). The evidences show that, in irradiated cells, some signals are continually released from a nucleus or cytoplasm even in the G0-like cells to operate some sort of protein machineries involved in mitochondrial fission. It is inferred that this delayed mitochondrial fragmentation is strongly related to their dysfunction, and hence might modulate radiobiological effects such as mutation or cell death.

  1. QSAR model for predicting cell viability of human embryonic kidney cells exposed to SiO₂ nanoparticles.

    PubMed

    Manganelli, Serena; Leone, Caterina; Toropov, Andrey A; Toropova, Alla P; Benfenati, Emilio

    2016-02-01

    A predictive model for the viability (%) of cultured human embryonic kidney cells (HEK293) exposed to 20 and 50 nm silica nanoparticles was built using 'optimal descriptors' as mathematical functions of size, concentration and exposure time. The calculation was carried out with CORAL software (http://www.insilico.eu/coral/) on five random splits of combined systems (particle size-particle concentration-cell exposure time) into training, calibration, and validation sets. The R(2) values of the best models were above 0.68. The average statistical quality of the model for the viability (%) of HEK293 exposed to different concentrations of silica nanoparticles measured by MTT assay is satisfactory. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Human neuroblastoma cells exposed to hypoxia: induction of genes associated with growth, survival, and aggressive behavior.

    PubMed

    Jögi, Annika; Vallon-Christersson, Johan; Holmquist, Linda; Axelson, Håkan; Borg, Ake; Påhlman, Sven

    2004-05-01

    We have recently found that cells derived from human neuroblastoma, a sympathetic nervous system (SNS) tumor, dedifferentiate and acquire a neural crest-like phenotype when exposed to hypoxia. In the present study, global analysis of gene expression and quantitative PCR of relevant genes showed that hypoxia provokes a general adaptive response in neuroblastoma cells and confirm loss of the neuronal phenotype and gain of stem-cell characteristics. Of the approximately 17,000 genes and ESTs analyzed, 199 were consistently upregulated and 36 were downregulated more than 2-fold by hypoxia. As anticipated, several genes involved in glucose and iron metabolism and neovascularization were upregulated, the latter group we here show to include the gene encoding chromogranin C and its cleavage product, secretoneurin, a vascular smooth muscle cell mitogen. We also observed upregulation of genes implicated in cell survival and growth, such as vascular endothelial growth factor (VEGF), neuropilin 1, adrenomedullin, and IGF-2. Several metallothioneins, which are linked to tumor drug resistance, were upregulated, whereas the expression of MDR1 decreased. In hypoxic neuroblastoma cells, proneuronal lineage specifying transcription factors, and their dimerization partner E2-2, were downregulated, whereas their inhibitors Id2 and HES-1 were induced, providing a molecular mechanism for the hypoxia-provoked dedifferentiation of neuroblastoma cells.

  3. Fate of D3 mouse embryonic stem cells exposed to X-rays or carbon ions.

    PubMed

    Luft, S; Pignalosa, D; Nasonova, E; Arrizabalaga, O; Helm, A; Durante, M; Ritter, S

    2014-01-15

    The risk of radiation exposure during embryonic development is still a major problem in radiotoxicology. In this study we investigated the response of the murine embryonic stem cell (mESC) line D3 to two radiation qualities: sparsely ionizing X-rays and densely ionizing carbon ions. We analyzed clonogenic cell survival, proliferation, induction of chromosome aberrations as well as the capability of cells to differentiate to beating cardiomyocytes up to 3 days after exposure. Our results show that, for all endpoints investigated, carbon ions are more effective than X-rays at the same radiation dose. Additionally, in long term studies (≥8 days post-irradiation) chromosomal damage and the pluripotency state were investigated. These studies reveal that pluripotency markers are present in the progeny of cells surviving the exposure to both radiation types. However, only in the progeny of X-ray exposed cells the aberration frequency was comparable to that of the control population, while the progeny of carbon ion irradiated cells harbored significantly more aberrations than the control, generally translocations. We conclude that cells surviving the radiation exposure maintain pluripotency but may carry stable chromosomal rearrangements after densely ionizing radiation.

  4. Flow cytometric analysis to evaluate physiological alterations in herbicide-exposed Chlamydomonas moewusii cells.

    PubMed

    Prado, Raquel; Rioboo, Carmen; Herrero, Concepción; Suárez-Bregua, Paula; Cid, Angeles

    2012-03-01

    Investigation of herbicide toxicology in non-target aquatic primary producers such as microalgae is of great importance from an ecological point of view. In order to study the toxicity of the widely used herbicide paraquat on freshwater green microalga Chlamydomonas moewusii, physiological changes associated with 96 h-exposures to this pollutant were monitored using flow cytometry (FCM) technique. Intracellular reactive oxygen species concentration, cytoplasmic membrane potential, metabolic activity and cell protein content were monitored to evaluate the toxicological impact of paraquat on algal physiology. Results showed that herbicide paraquat induced oxidative stress in C. moewusii cells, as it indicated the increase of both superoxide anion and hydrogen peroxide levels observed in non-chlorotic cells of cultures exposed to increasing herbicide concentrations. Furthermore, a progressive increase in the percentage of depolarised cells and a decrease in the metabolic activity level were observed in response to paraquat when non-chlorotic cells were analysed. Chlorotic cells were probably non-viable cells, based on the cytoplasmic membrane depolarisation, its metabolically non-active state and its drastically reduced protein content. In view of the obtained results, we have concluded that a range of significant physiological alterations, detected by flow cytometry, occur when C. moewusii, an ubiquitous microalga in freshwater environments, is challenged with environmentally relevant concentrations of the herbicide paraquat.

  5. Regulation of gene expression in Dictyostelium discoideum cells exposed to immobilized carbohydrates

    PubMed Central

    Bozzaro, Salvatore; Perlo, Carla; Ceccarelli, Adriano; Mangiarotti, Giorgio

    1984-01-01

    When amoebae of Dictyostelium discoideum develop on gels of polyacrylamide that are derivatized with glucosides, they become capable of aggregation at the same time as cells not exposed to glucosides. However, the aggregation centers and streams of adherent cells formed on immobilized glucosides suddenly disintegrate. The cells repeatedly re-aggregate, but never form tight aggregates as they do on other substrata. Tight aggregates formed in the absence of glucosides disperse after their transfer to glucoside gels, and the cells undergo aggregation-disaggregation cycles. The formation of tight aggregates is correlated with the expression of specific post-aggregative poly(A)+ RNAs. These RNAs are not expressed in cells developing on glucoside gels, and the dispersal of tight aggregates on such gels is accompanied by the almost complete loss of these RNAs. A developmentally regulated membrane glycoprotein called contact site A, which is a marker of aggregation-competent cells, is normally expressed on glucoside gels. Cyclic AMP is also produced, indicating that the strong increase of adenylate cyclase activity during the preaggregation phase is not affected. In conclusion, cell contact with immobilized glucosides specifically inhibits postaggregative gene expression and arrests development at the aggregation stage. ImagesFig. 1.Fig. 2.Fig. 3.Fig. 5.Fig. 7. PMID:16453493

  6. Regulation of gene expression in Dictyostelium discoideum cells exposed to immobilized carbohydrates.

    PubMed

    Bozzaro, S; Perlo, C; Ceccarelli, A; Mangiarotti, G

    1984-01-01

    When amoebae of Dictyostelium discoideum develop on gels of polyacrylamide that are derivatized with glucosides, they become capable of aggregation at the same time as cells not exposed to glucosides. However, the aggregation centers and streams of adherent cells formed on immobilized glucosides suddenly disintegrate. The cells repeatedly re-aggregate, but never form tight aggregates as they do on other substrata. Tight aggregates formed in the absence of glucosides disperse after their transfer to glucoside gels, and the cells undergo aggregation-disaggregation cycles. The formation of tight aggregates is correlated with the expression of specific post-aggregative poly(A) RNAs. These RNAs are not expressed in cells developing on glucoside gels, and the dispersal of tight aggregates on such gels is accompanied by the almost complete loss of these RNAs. A developmentally regulated membrane glycoprotein called contact site A, which is a marker of aggregation-competent cells, is normally expressed on glucoside gels. Cyclic AMP is also produced, indicating that the strong increase of adenylate cyclase activity during the preaggregation phase is not affected. In conclusion, cell contact with immobilized glucosides specifically inhibits postaggregative gene expression and arrests development at the aggregation stage.

  7. Microtubule Formation and Activities of Antioxidative Enzymes in PC12 Cells Exposed to Phosphatidylcholine Hydroperoxides

    PubMed Central

    Yamanaka, Yukako; Yoshida-Yamamoto, Shumi; Doi, Hiroshi

    2012-01-01

    Aging increases free radical generation and lipid oxidation and, thereby, mediates neurodegenerative diseases. As the brain is rich in lipids (polyunsaturated fatty acids), the antioxidative system plays an important role in protecting brain tissues from oxidative injury. The changes in microtubule formation and antioxidative enzyme activities have been investigated in rat pheochromocytoma PC12 cells exposed to various concentrations of phosphatidylcholine hydroperoxides (PCOOH). We measured three typical antioxidative enzymes, superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase (CAT). The microtubule assembly system was dependent on the antioxidative enzyme system in cells exposed to oxidative stress. The activities of the three enzymes increased in a PCOOH exposure-dependent manner. In particular, the changes in the activity as a result of PCOOH exposure were similar in the three antioxidative enzymes. This is the first report indicating the compatibility between the tubulin-microtubule and antioxidative enzyme systems in cells that deteriorate as a result of phospholipid hydroperoxide administration from an exterior source. The descending order of sensitivity of the three enzymes to PCOOH is also discussed. PMID:23443078

  8. Cell-free DNA in the urine of rats exposed to ionizing radiation.

    PubMed

    Abdullaev, Serazhutdin A; Minkabirova, Gulchachak M; Bezlepkin, Vladimir G; Gaziev, Azhub I

    2015-08-01

    Investigation of cell-free DNA (cf-DNA) in body fluids, as a potential biomarker for assessing the effect of ionizing radiation on the organism, is of considerable interest. We investigated changes in the contents of cell-free mitochondrial DNA (cf-mtDNA) and cell-free nuclear DNA (cf-nDNA) in the urine of X-ray-exposed rats. Assays of cf-mtDNA and cf-nDNA were performed by a real-time PCR in rat urine collected before and after irradiation of animals with doses of 3 and 5 Gy. We also determined the presence of mutations in urine cf-mtDNA, as recognized by Surveyor nuclease. A sharp increase in cf-mtDNA and cf-nDNA in the urine of irradiated rats was observed within 24 h after exposure, followed by a decrease to normal levels. In all cases, the contents of cf-mtDNA fragment copies (estimated by gene tRNA) were significantly higher than those of cf-nDNA estimated by gene GAPDH. A certain portion of mutant cf-mtDNA fragments was detected in the urine of exposed rats, whereas they were absent in the urine of the same animals before irradiation. These preliminary data also suggest that the increased levels of urine cf-mtDNA and cf-nDNA may be a potential biomarker for noninvasive assessment of how the organism responds to ionizing radiation influence.

  9. Genotoxic signature in cord blood cells of newborns exposed in utero to a Zidovudine-based antiretroviral combination.

    PubMed

    André-Schmutz, Isabelle; Dal-Cortivo, Liliane; Six, Emmanuelle; Kaltenbach, Sophie; Cocchiarella, Fabienne; Le Chenadec, Jerome; Cagnard, Nicolas; Cordier, Anne-Gael; Benachi, Alexandra; Mandelbrot, Laurent; Azria, Elie; Bouallag, Naima; Luce, Sonia; Ternaux, Brigitte; Reimann, Christian; Revy, Patrick; Radford-Weiss, Isabelle; Leschi, Cristina; Recchia, Alessandra; Mavilio, Fulvio; Cavazzana, Marina; Blanche, Stéphane

    2013-07-15

    The genotoxicity of zidovudine has been established in experimental models. The objective of the study was to identify genotoxicity markers in cord blood cells from newborns exposed in utero to antiretroviral (ARV) combinations containing zidovudine. Cells were investigated by karyotyping and gene expression analysis of the CD34(+) hematopoietic stem/progenitor cell (HPC) compartment. Karyotyping of the cord blood cells from 15 ARV-exposed newborns and 12 controls revealed a higher proportion of aneuploid cells in the exposed group (median, 18.8% [interquartile range, 10.0%-26.7%] vs 6.6% [interquartile range, 3.1%-11.7%]; P < .001). All chromosomes were involved, with a random distribution of these alterations. Gene expression profiling of CD34(+) HPCs from 7 ARV-exposed and 6 control newborns revealed that >300 genes were significantly upregulated or downregulated by at least 1.5-fold in the exposed group (P < .05 for all comparisons). Significant alterations of genes involved in cell cycle control, mitotic checkpoints, and DNA repair were identified. Although this study does not allow discrimination between the roles of each of the 3 drugs, both cytogenetic and transcriptional findings are similar to those in cellular experiments that used zidovudine alone. The cord blood cells, including hematopoietic stem cells, from newborns exposed in utero to a zidovudine-based ARV combination present cytogenetic and transcriptional abnormalities compatible with DNA damage.

  10. Chromosome Aberrations in Normal and Ataxia-Telangiectasia Cells Exposed to Heavy Ions

    NASA Technical Reports Server (NTRS)

    Kawata, T.; Ito, H.; Liu, C.; Shigematsu, N.; George, K.; Cucinotta, F. A.

    2007-01-01

    Although cells derived from Ataxia Telangiectasia (AT) patients are known to exhibit abnormal responses to ionizing radiations, its underlying mechanism still remains unclear. Previously, the authors reported that at the same gamma-irradiation dose AT cells show higher frequencies of misrepair and deletions compared to normal human fibroblast cells. In this study, we investigated the effects of heavy ions beams on chromosomal aberrations in normal and AT cells. Normal and AT fibroblast cells arrested at G0/G1 phase were irradiated with 2 Gy of X-rays, 490 MeV/u Silicon (LET 55 keV/m), 500 MeV/u Iron (LET 185 keV/m) and 200 MeV/u Iron (LET 440 keV/m) particles, and then cells were allowed to repair for 24 hours at 37 degrees before subculture. Calyculin-A induced PCC method was employed to collect G2/M chromosomes and whole DNA probes 1 and 3 were used to analyze chromosomal aberrations such as color-junctions, deletions, simple exchanges (incomplete and reciprocal exanges) and complex-type exchanges. The percentages of aberrant cells were higher when normal and AT cells were exposed to heavy ions compared to X-rays, and had a tendency to increase with increasing LET up to 185 keV/m and then decreased at 440 keV/m. When the frequency of color-junctions per cell was compared after X-ray exposure, AT cells had around three times higher frequency of color-junctions (mis-rejoining) than normal cells. However, at 185 keV/m there was no difference in the frequency of color-junctions between two cell lines. It was also found that the frequency of simple exchanges per cell was almost constant in AT cells regardless LET levels, but it was LET dependent for normal cells. Interestingly, the frequency of simple exchanges was higher for AT cells when it was compared at 185 keV/m but AT cells had more complex-type exchanges at the same LET levels. Heavy ions are more efficient in inducing chromosome aberrations in normal and AT cells compared to X-rays, and the aberration types

  11. Radiation-Induced Bystander Effects in A549 Cells Exposed to 6 MV X-rays.

    PubMed

    Yang, Shuning; Xu, Jing; Shao, Weixian; Geng, Chong; Li, Jia; Guo, Feng; Miao, Hui; Shen, Wenbin; Ye, Tao; Liu, Yazhou; Xu, Haiting; Zhang, Xuguang

    2015-07-01

    The aim of the study is to explore the bystander effects in A549 cells that have been exposed to 6MV X-ray. Control group, irradiated group, irradiated conditioned medium (ICM)-received group, and fresh medium group were designed in this study. A549 cells in the logarithmic growth phase were irradiated with 6MV X-ray at 0, 0.5, 1, 1.5, and 2. In ICM-received group, post-irradiation A549 cells were cultured for 3 h and were transferred into non-irradiated A549 cells for further cultivation. Clone forming test was applied to detect the survival fraction of cells. Annexin V-FITC/PI double-staining assay was used to detect the apoptosis of A549 cells 24, 48, 72, and 96 h after 2-Gy 6MV X-ray irradiation, and the curves of apoptosis were drawn. The changes in the cell cycles 4, 48, 72, and 96 h after 2-Gy 6MV X-ray irradiation were detected using PI staining flow cytometry. With the increase of irradiation dose, the survival fraction of A549 cells after the application of 0.5 Gy irradiation was decreasing continuously. In comparison to the control group, the apoptosis rate of the ICM-received group was increased in a time-dependent pattern, with the highest apoptosis rate observed at 72 h (p < 0.05). Cell count in G2/M stages was obviously increased compared with that of the control group (p < 0.05), with the highest count observed at 72 h, after which G2/M stage arrest was diminished. ICM can cause apparent A549 cell damage, indicating that 6MV X-ray irradiation can induce bystander effect on A549 cells, which reaches a peak at 72 h.

  12. Antioxidative capacity and enzyme activity in Haematococcus pluvialis cells exposed to superoxide free radicals

    NASA Astrophysics Data System (ADS)

    Liu, Jianguo; Zhang, Xiaoli; Sun, Yanhong; Lin, Wei

    2010-01-01

    The antioxidative capacity of astaxanthin and enzyme activity of reactive oxygen eliminating enzymes such as superoxide dismutase (SOD), peroxidase (POD), catalase (CAT) and ascorbate peroxidase (APX) were studied in three cell types of Haematococcus pluvialis exposed to high concentrations of a superoxide anion radical (O{2/-}). The results show that defensive enzymes and astaxanthin-related mechanisms were both active in H. pluvialis during exposure to reactive oxygen species (ROS) such as O{2/-}. Astaxanthin reacted with ROS much faster than did the protective enzymes, and had the strongest antioxidative capacity to protect against lipid peroxidation. The defensive mechanisms varied significantly between the three cell types and were related to the level of astaxanthin that had accumulated in those cells. Astaxanthin-enriched red cells had the strongest antioxidative capacity, followed by brown cells, and astaxanthin-deficient green cells. Although there was no significant increase in expression of protective enzymes, the malondialdehyde (MDA) content in red cells was sustained at a low level because of the antioxidative effect of astaxanthin, which quenched O{2/-} before the protective enzymes could act. In green cells, astaxanthin is very low or absent; therefore, scavenging of ROS is inevitably reliant on antioxidative enzymes. Accordingly, in green cells, these enzymes play the leading role in scavenging ROS, and the expression of these enzymes is rapidly increased to reduce excessive ROS. However, because ROS were constantly increased in this study, the enhance enzyme activity in the green cells was not able to repair the ROS damage, leading to elevated MDA content. Of the four defensive enzymes measured in astaxanthin-deficient green cells, SOD eliminates O{2/-}, POD eliminates H2O2, which is a by-product of SOD activity, and APX and CAT are then initiated to scavenge excessive ROS.

  13. Altered Natural Killer Cell Function in HIV-Exposed Uninfected Infants.

    PubMed

    Smith, Christiana; Jalbert, Emilie; de Almeida, Volia; Canniff, Jennifer; Lenz, Laurel L; Mussi-Pinhata, Marisa M; Cohen, Rachel A; Yu, Qilu; Amaral, Fabiana R; Pinto, Jorge; Alarcon, Jorge O; Siberry, George; Weinberg, Adriana

    2017-01-01

    HIV-exposed uninfected (HEU) infants have higher rates of severe and fatal infections compared with HIV-unexposed (HUU) infants, likely due to immune perturbations. We hypothesized that alterations in natural killer (NK) cell activity might occur in HEU infants and predispose them to severe infections. Case-control study using cryopreserved peripheral blood mononuclear cells (PBMCs) at birth and 6 months from HEU infants enrolled from 2002 to 2009 and HUU infants enrolled from 2011 to 2013. NK cell phenotype and function were assessed by flow cytometry after 20-h incubation with and without K562 cells. The proportion of NK cells among PBMCs was lower at birth in 12 HEU vs. 22 HUU (1.68 vs. 10.30%, p < 0.0001) and at 6 months in 52 HEU vs. 72 HUU (3.09 vs. 4.65%, p = 0.0005). At birth, HEU NK cells demonstrated increased killing of K562 target cells (p < 0.0001) and increased expression of CD107a (21.65 vs. 12.70%, p = 0.047), but these differences resolved by 6 months. Stimulated HEU NK cells produced less interferon (IFN)γ at birth (0.77 vs. 2.64%, p = 0.008) and at 6 months (4.12 vs. 8.39%, p = 0.001), and showed reduced perforin staining at 6 months (66.95 vs. 77.30%, p = 0.0008). Analysis of cell culture supernatants indicated that lower NK cell activity in HEU was associated with reduced interleukin (IL)-12, IL-15, and IL-18. Addition of recombinant human IL-12 to stimulated HEU PBMCs restored IFNγ production to that seen in stimulated HUU cultures. NK cell proportion, phenotype, and function are altered in HEU infants. NK cell cytotoxicity and degranulation are increased in HEU at birth, but HEU NK cells have reduced IFNγ and perforin production, suggesting an adequate initial response, but decreased functional reserve. NK cell function improved with addition of exogenous IL-12, implicating impaired production of IL-12 by accessory cells. Alterations in NK cell and accessory cell function may contribute to the

  14. The BIANCA model/code of radiation-induced cell death: application to human cells exposed to different radiation types.

    PubMed

    Ballarini, Francesca; Altieri, Saverio; Bortolussi, Silva; Carante, Mario; Giroletti, Elio; Protti, Nicoletta

    2014-08-01

    This paper presents a biophysical model of radiation-induced cell death, implemented as a Monte Carlo code called BIophysical ANalysis of Cell death and chromosome Aberrations (BIANCA), based on the assumption that some chromosome aberrations (dicentrics, rings, and large deletions, called ‘‘lethal aberrations’’) lead to clonogenic inactivation. In turn, chromosome aberrations are assumed to derive from clustered, and thus severe, DNA lesions (called ‘‘cluster lesions,’’ or CL) interacting at the micrometer scale; the CL yield and the threshold distance governing CL interaction are the only model parameters. After a pilot study on V79 hamster cells exposed to protons and carbon ions, in the present work the model was extended and applied to AG1522 human cells exposed to photons, He ions, and heavier ions including carbon and neon. The agreement with experimental survival data taken from the literature supported the assumptions. In particular, the inactivation of AG1522 cells was explained by lethal aberrations not only for X-rays, as already reported by others, but also for the aforementioned radiation types. Furthermore, the results are consistent with the hypothesis that the critical initial lesions leading to cell death are DNA cluster lesions having yields in the order of *2 CL Gy-1 cell-1 at low LET and*20 CL Gy-1 cell-1 at high LET, and that the processing of these lesions is modulated by proximity effects at the micrometer scale related to interphase chromatin organization. The model was then applied to calculate the fraction of inactivated cells, as well as the yields of lethal aberrations and cluster lesions, as a function of LET; the results showed a maximum around 130 keV/lm, and such maximum was much higher for cluster lesions and lethal aberrations than for cell inactivation.

  15. Colon Stem Cell and Crypt Dynamics Exposed by Cell Lineage Reconstruction

    PubMed Central

    Itzkovitz, Shalev; Elbaz, Judith; Maruvka, Yosef E.; Segev, Elad; Shlush, Liran I.; Dekel, Nava; Shapiro, Ehud

    2011-01-01

    Stem cell dynamics in vivo are often being studied by lineage tracing methods. Our laboratory has previously developed a retrospective method for reconstructing cell lineage trees from somatic mutations accumulated in microsatellites. This method was applied here to explore different aspects of stem cell dynamics in the mouse colon without the use of stem cell markers. We first demonstrated the reliability of our method for the study of stem cells by confirming previously established facts, and then we addressed open questions. Our findings confirmed that colon crypts are monoclonal and that, throughout adulthood, the process of monoclonal conversion plays a major role in the maintenance of crypts. The absence of immortal strand mechanism in crypts stem cells was validated by the age-dependent accumulation of microsatellite mutations. In addition, we confirmed the positive correlation between physical and lineage proximity of crypts, by showing that the colon is separated into small domains that share a common ancestor. We gained new data demonstrating that colon epithelium is clustered separately from hematopoietic and other cell types, indicating that the colon is constituted of few progenitors and ruling out significant renewal of colonic epithelium from hematopoietic cells during adulthood. Overall, our study demonstrates the reliability of cell lineage reconstruction for the study of stem cell dynamics, and it further addresses open questions in colon stem cells. In addition, this method can be applied to study stem cell dynamics in other systems. PMID:21829376

  16. [The intervention of nicotinamide on skin melanocyte's cell proliferation after UVA (365 nm) exposed.].

    PubMed

    Patam, Muhammad; Jin, Xi-peng; Pan, Jian-ying; Shen, Guang-zu; Jin, Tai-Yi

    2005-02-01

    To investigate the interference effect of nicotinamide on UVA-induced cell proliferation in human skin melanocyte. To apply the optimum UVA dose expected to cause cell proliferation: 0.2 cm2, nicotinamide was added after the 0.2 cm2 UVA exposure immediately or 48 h later, then the rate of cell proliferation, calcium concentration and the activities of Na+-K+, Ca2+-ATP enzymes of melanocytes were measured respectively. After treatment with 1.000 mg/ml nicotinamide following UVA exposure, the rate of cell proliferation was decreased significantly 24 hours later. Treatment with 0.125 mg/ml nicotinamide 48 hours after UVA exposure also significantly inhibited the cell proliferation; 1.25 mg/ml nicotinamide increased calcium concentration in cells; 0.250 mg/ml nicotinamide increased the activities of Na+-K+, Ca2+-ATP enzymes in melanocytes (P < 0.05). Nicotinamide has more obvious effect on inhibiting melanocyte's proliferation if added immediately following UVA exposure. Our discovery indicated that nicotinamide may affect the melanocyte through modulating the calcium concentration. It is possible to consider nicotinamide as an efficient and safe sun screen to provide a certain level of protection for UVA exposed skin.

  17. Proteome Analysis of Human Follicular Thyroid Cancer Cells Exposed to the Random Positioning Machine.

    PubMed

    Bauer, Johann; Kopp, Sascha; Schlagberger, Elisabeth Maria; Grosse, Jirka; Sahana, Jayashree; Riwaldt, Stefan; Wehland, Markus; Luetzenberg, Ronald; Infanger, Manfred; Grimm, Daniela

    2017-03-03

    Several years ago, we detected the formation of multicellular spheroids in experiments with human thyroid cancer cells cultured on the Random Positioning Machine (RPM), a ground-based model to simulate microgravity by continuously changing the orientation of samples. Since then, we have studied cellular mechanisms triggering the cells to leave a monolayer and aggregate to spheroids. Our work focused on spheroid-related changes in gene expression patterns, in protein concentrations, and in factors secreted to the culture supernatant during the period when growth is altered. We detected that factors inducing angiogenesis, the composition of integrins, the density of the cell monolayer exposed to microgravity, the enhanced production of caveolin-1, and the nuclear factor kappa B p65 could play a role during spheroid formation in thyroid cancer cells. In this study, we performed a deep proteome analysis on FTC-133 thyroid cancer cells cultured under conditions designed to encourage or discourage spheroid formation. The experiments revealed more than 5900 proteins. Their evaluation confirmed and explained the observations mentioned above. In addition, we learned that FTC-133 cells growing in monolayers or in spheroids after RPM-exposure incorporate vinculin, paxillin, focal adhesion kinase 1, and adenine diphosphate (ADP)-ribosylation factor 6 in different ways into the focal adhesion complex.

  18. The localization of DMPO spin adducts of OH in endothelial cells exposed to hydrogen peroxide.

    PubMed

    Kaneko, M; Kodama, M; Inoue, F

    1995-11-01

    Examination by electron spin resonance (ESR) spectroscopy revealed the localization of 5,5-dimethyl-l-pyrroline-N-oxide (DMPO) spin adducts of hydroxyl radicals (.OH) produced by bovine endothelial cells exposed to hydrogen peroxide. Addition of 10 mM chromium oxalate, a line-broadening agent, to the reaction mixture virtually abolished the signal of DMPO-OH spin adducts. Moreover, the spin adducts were recovered in the filtrated fraction of the cell suspension. We, therefore, concluded that the location of DMPO-OH due to .OH radicals produced by endothelial cells was extracellular. Contrastingly, the site of formation of DMPO-OH was confirmed to be intracellular by the effect of Desferal, an iron chelator, and the effect of poly(ethylene glycol), an extracellular scavenger of OH radicals, as previously reported. The DMPO-OH adducts in the cell suspension mixture were degraded by a cyanide sensitive pathway and they were apparently more unstable than in the extracellular fraction. The initial amount of DMPO-OH adducts formed in endothelial cells could potentially be monitored by the DMPO-OH signals in the extracellular reaction mixture better than those in the cell suspension mixture.

  19. Proteome Analysis of Human Follicular Thyroid Cancer Cells Exposed to the Random Positioning Machine

    PubMed Central

    Bauer, Johann; Kopp, Sascha; Schlagberger, Elisabeth Maria; Grosse, Jirka; Sahana, Jayashree; Riwaldt, Stefan; Wehland, Markus; Luetzenberg, Ronald; Infanger, Manfred; Grimm, Daniela

    2017-01-01

    Several years ago, we detected the formation of multicellular spheroids in experiments with human thyroid cancer cells cultured on the Random Positioning Machine (RPM), a ground-based model to simulate microgravity by continuously changing the orientation of samples. Since then, we have studied cellular mechanisms triggering the cells to leave a monolayer and aggregate to spheroids. Our work focused on spheroid-related changes in gene expression patterns, in protein concentrations, and in factors secreted to the culture supernatant during the period when growth is altered. We detected that factors inducing angiogenesis, the composition of integrins, the density of the cell monolayer exposed to microgravity, the enhanced production of caveolin-1, and the nuclear factor kappa B p65 could play a role during spheroid formation in thyroid cancer cells. In this study, we performed a deep proteome analysis on FTC-133 thyroid cancer cells cultured under conditions designed to encourage or discourage spheroid formation. The experiments revealed more than 5900 proteins. Their evaluation confirmed and explained the observations mentioned above. In addition, we learned that FTC-133 cells growing in monolayers or in spheroids after RPM-exposure incorporate vinculin, paxillin, focal adhesion kinase 1, and adenine diphosphate (ADP)-ribosylation factor 6 in different ways into the focal adhesion complex. PMID:28273809

  20. Transcriptional and Secretomic Profiling of Epidermal Cells Exposed to Alpha Particle Radiation

    PubMed Central

    Chauhan, Vinita; Howland, Matthew; Greene, Hillary Boulay; Wilkins, Ruth C

    2012-01-01

    Alpha (α)-particle emitters are probable isotopes to be used in a terrorist attack. The development of biological assessment tools to identify those who have handled these difficult to detect materials would be an asset to our current forensic capacity. In this study, for the purposes of biomarker discovery, human keratinocytes were exposed to α-particle and X-radiation (0.98 Gy/h at 0, 0.5, 1.0, 1.5 Gy) and assessed for differential gene and protein expression using microarray and Bio-Plex technology, respectively. Secretomic analysis of supernatants showed expression of two pro-inflammatory cytokines (IL-13 and PDGF-bb) to be exclusively affected in α-particle exposed cells. The highest dose of α-particle radiation modulated a total of 67 transcripts (fold change>|1.5|, (False discovery rate) FDR<0.05) in exposed cells. Several genes which responded with high expression levels (>2 fold) included KIF20A, NEFM, C7orf10, HIST1H2BD, BMP6, and HIST1H2AC. Among the high expressing genes, five (CCNB2, BUB1, NEK2, CDC20, AURKA) were also differentially expressed at the medium (1.0 Gy) dose however, these genes were unmodulated following exposure to X-irradiation. Networks of these genes clustered around tumor protein-53 and transforming growth factor-beta signaling. This study has identified some potential gene /protein responses and networks that may be validated further to confirm their specificity and potential to be signature biomarkers of α-particle exposure. PMID:23002402

  1. Innate Lymphoid Cells Mediate Pulmonary Eosinophilic Inflammation, Airway Mucous Cell Metaplasia, and Type 2 Immunity in Mice Exposed to Ozone.

    PubMed

    Kumagai, Kazuyoshi; Lewandowski, Ryan P; Jackson-Humbles, Daven N; Buglak, Nicholas; Li, Ning; White, Kaylin; Van Dyken, Steven J; Wagner, James G; Harkema, Jack R

    2017-01-01

    Exposure to elevated levels of ambient ozone in photochemical smog is associated with eosinophilic airway inflammation and nonatopic asthma in children. In the present study, we determined the role of innate lymphoid cells (ILCs) in the pathogenesis of ozone-induced nonatopic asthma by using lymphoid cell-sufficient C57BL/6 mice, ILC-sufficient Rag2(-/-) mice (devoid of T and B cells), and ILC-deficient Rag2(-/-)Il2rg(-/-) mice (depleted of all lymphoid cells including ILCs). Mice were exposed to 0 or 0.8 parts per million ozone for 1 day or 9 consecutive weekdays (4 hr/day). A single exposure to ozone caused neutrophilic inflammation, airway epithelial injury, and reparative DNA synthesis in all strains of mice, irrespective of the presence or absence of ILCs. In contrast, 9-day exposures induced eosinophilic inflammation and mucous cell metaplasia only in the lungs of ILC-sufficient mice. Repeated ozone exposures also elicited increased messenger RNA expression of transcripts associated with type 2 immunity and airway mucus production in ILC-sufficient mice. ILC-deficient mice repeatedly exposed to ozone had no pulmonary pathology or increased gene expression related to type 2 immunity. These results suggest a new paradigm for the biologic mechanisms underlying the development of a phenotype of childhood nonatopic asthma that has been linked to ambient ozone exposures.

  2. A case of epidermodysplasia verruciformis with squamous cell carcinomas on non-sun-exposed areas of skin.

    PubMed

    Ansarin, Habib; Tajziehchi, Leila; Shaianfar, Nasrin

    2007-04-01

    Epidermodysplasia verruciformis is an inherited disorder, characterized by multiple plane warts, pityriasis versicolor-like lesions, defects of cell-mediated immunity, and tendency to develop skin malignancies, primarily on sun-exposed areas. In this article, we present a case of epidermodysplasia verruciformis with multiple plane warts, pityriasis versicolor-like lesions, and squamous cell carcinomas on non-sun-exposed areas of skin. After acitretin prescription, significant improvement was found in plane warts, but not in pityriasis versicolor-like lesions.

  3. Reduced cell viability and apoptosis induction in human thyroid carcinoma and mesothelioma cells exposed to cidofovir.

    PubMed

    Catalani, Simona; Palma, Francesco; Battistelli, Serafina; Nuvoli, Barbara; Galati, Rossella; Benedetti, Serena

    2017-02-20

    Besides its well-recognized antiviral activity, Cidofovir (CDV) has been shown to exert anticancer properties both within in vitro and in vivo models. The aim of this study was to evaluate the effects of CDV on still unexplored cultured cancer cells from human mesothelioma as well as breast, colon, liver, lung, prostate, and thyroid carcinomas. Overall, a dose- and time-dependent inhibition of cell viability was observed after CDV exposure. To clarify the mechanisms underlying CDV action, apoptotic cell death was investigated in two infected cell lines [Ist-Mes1 and Ist-Mes2 mesothelioma cells (SV40+)] and in two uninfected cell lines (NCI-H2425 mesothelioma cells and FTC-133 thyroid cancer cells), which resulted the most sensitive to CDV treatment. Reduced expression of procaspase-3 and increased expression of PARP p85 fragment were observed in both infected and uninfected mesothelioma cells, indicating apoptosis induction by CDV in a virus-independent manner. Similarly, the increase of the pro-apoptotic proteins p53, cytochrome c and caspase-3, the decrease of the survival protein Bcl-x, and the increment of Bax/Bcl-2 ratio revealed the occurrence of apoptosis in CDV-treated FTC-133. The presence of nuclear DNA fragmentation confirmed apoptotic cell death by CDV. Overall, our findings warrant further investigations to explore the therapeutic potential of CDV for human mesothelioma and follicular thyroid carcinoma.

  4. From the Cover: Exposing Imidacloprid Interferes With Neurogenesis Through Impacting on Chick Neural Tube Cell Survival.

    PubMed

    Liu, Meng; Wang, Guang; Zhang, Shi-Yao; Zhong, Shan; Qi, Guo-Long; Wang, Chao-Jie; Chuai, Manli; Lee, Kenneth Ka Ho; Lu, Da-Xiang; Yang, Xuesong

    2016-09-01

    As a neonicotinoid pesticide, imidacloprid is widely used to control insects in agriculture and fleas on domestic animals. However, it is not known whether imidacloprid exposure negatively affects neurogenesis during embryonic development. In this study, using a chick embryo model, we investigated the effects of imidacloprid exposure on neurogenesis at the earliest stage and during late-stage embryo development. Exposing HH0 chick embryos to imidacloprid in EC culture caused neural tube defects (NTDs) and neuronal differentiation dysplasia as determined by NF/Tuj1 labeling. Furthermore, we found that F-actin accumulation on the apical side of the neural tube was suppressed by exposure to imidacloprid, and the expression of BMP4 and Shh on the dorsal and ventral sides of the neural tubes, respectively, were also reduced, which in turn affects the dorsolateral hinge points during bending of the neural plate. In addition, exposure to imidacloprid reduced cell proliferation and increased cell apoptosis, as determined by pHIS3 labeling and TUNEL staining, respectively, also contributing to the malformation. We obtained similar results in late-stage embryos exposed to imidacloprid. Finally, a bioinformatics analysis was employed to determine which genes identified in this study were involved in NTDs. The experimental evidence and bioinformatics analysis suggested that imidacloprid exposure during chick embryo development could increase the risk of NTDs and neural dysplasia.

  5. Tumor necrosis factor alpha gene expression in human monocytic THP-1 cells exposed to beryllium.

    PubMed

    Galbraith, G M; Pandey, J P; Schmidt, M G; Arnaud, P; Goust, J M

    1996-01-01

    Chronic beryllium disease, which results from occupational exposure to particulate beryllium, is characterized by the development of lung granulomas and progressive pulmonary fibrosis. Increased production of proinflammatory cytokines (e.g., tumor necrosis factor alpha and interleukin-1 beta) by pulmonary alveolar macrophages occurs in many chronic fibrotic lung diseases and is thought to contribute to the disease process. The purpose of the present study was to investigate cytokine production by human monocytic cells exposed to beryllium in vitro. The results indicated that such cells respond to beryllium ions in the presence of fluoride by accumulation of messenger ribonucleic acid for both tumor necrosis factor alpha and interleukin-1 beta. These findings suggest that inhaled beryllium may directly stimulate the production of these cytokines by alveolar macrophages in vitro.

  6. Detection of programmed cell death in cells exposed to genotoxic agents using a caspase activation assay.

    PubMed

    Gehring, Michael E; Koty, Patrick P

    2005-01-01

    Many environmental toxins cause DNA damage. Cells that have sustained significant DNA damage must attempt to repair the damage prior to replication, in which aberrant base incorporation can result in an irreversible mutation. If a cell cannot repair the damage, however, it may commit suicide through a genetically regulated programmed cell death (PCD) pathway. Crucial to the ultimate execution of PCD is a family of cysteine proteases called caspases. Activation of these enzymes occurs late in the PCD pathway, when a cell can no longer avoid cell death, but earlier than other PCD markers, such as morphological changes or DNA fragmentation. This protocol details a method for using fluorochrome-conjugated caspase inhibitors for the detection of activated caspases in intact cells using fluorescent microscopy.

  7. Gene expression profile of Jurkat cells exposed to high power terahertz radiation

    NASA Astrophysics Data System (ADS)

    Grundt, Jessica E.; Roth, Caleb C.; Rivest, Benjamin D.; Doroski, Michael L.; Payne, Jason; Ibey, Bennett L.; Wilmink, Gerald J.

    2011-03-01

    Terahertz (THz) radiation sources are now being used in a host of military, defense, and medical applications. Widespread employment of these applications has prompted concerns regarding the health effects associated with THz radiation. In this study, we examined the gene expression profile of mammalian cells exposed to THz radiation. We hypothesized that if THz radiation couples directly to cellular constituents, then exposed cells may express a specific gene expression profile indicative of ensuing damage. To test this hypothesis, Jurkat cells were irradiated with a molecular gas THz laser (2.52 THz, 636 mWcm-2, durations: 5, 10, 20, 30, 40, or 50 minutes). Viability was assessed 24 h post-exposure using MTT assays, and gene expression profiles were evaluated 4 h post-exposure using mRNA microarrays. Comparable analyses were also performed for hyperthermic positive controls (44°C for 40 minutes). We found that cellular temperatures increased by ~6 °C during THz exposures. We also found that cell death increased with exposure duration, and the median lethal dose (LD50) was calculated to be ~44 minutes. The microarray data showed that THz radiation induced the transcriptional activation of genes associated with cellular proliferation, differentiation, transcriptional activation, chaperone protein stabilization, and apoptosis. For most genes, we found that the magnitude of differential expression was comparable for both the THz and thermal exposure groups; however, several genes were specifically activated by the THz exposure. These results suggest that THz radiation may elicit effects that are not exclusively due to the temperature rise created during THz exposures (i.e. thermal effects). In future work, we plan to verify the results of our microarray experiments using qPCR techniques.

  8. Nasal cell micronuclei, cytology and clinical symptoms in stainless steel production workers exposed to chromium.

    PubMed

    Huvinen, Markku; Mäkitie, Antti; Järventaus, Hilkka; Wolff, Henrik; Stjernvall, Tuula; Hovi, Arja; Hirvonen, Ari; Ranta, Riikka; Nurminen, Markku; Norppa, Hannu

    2002-09-01

    The objective of the present study was to determine whether workers in stainless steel production with low exposure to various forms of chromium show an increase in micronucleated nasal cells or an excess of nasal symptoms or disease. Altogether, 48 workers employed in a stainless steel production chain were studied, 29 of them in the steel melting shop with exposure to hexavalent chromium (Cr(6+)), 14 in the sintering and crushing departments of the ferrochromium plant with exposure to trivalent chromium (Cr(3+)) and five in the mine with exposure to chromite ore (Cr(3+)). Thirty-nine workers from the cold rolling mill, with very low exposure to chromium, served as referents. All the subjects were never smokers with a minimum of 14 years employment in the same department. There were no significant differences between the exposure groups and the referents regarding the mean frequency of centromere-negative or centromere-positive micronuclei (studied by pancentromeric fluorescence in situ hybridization), nasal diseases and symptoms or mucociliary clearance of the nasal cavity. No statistically significant differences in the incidence of cell atypia or inflammatory cells were detected between the exposed workers and the reference group, except for an increase in lymphocytes among the chromite ore workers. Anterior rhinoscopy indicated slight inflammatory changes in nasal mucosa and secretion more often in the Cr(6+) and Cr(3+) groups than in the referents, the Cr(6+)-exposed workers showing more livid or oedemic epithelium. In conclusion, the stainless steel production workers, with low exposure to dusts or fumes containing hexavalent or trivalent chromium, did not show clinical changes in the nasal mucosa or an increase in nasal cell micronuclei or symptoms of nasal diseases, except for slight changes in the nasal epithelium and secretion.

  9. Altered gene expression in HepG2 cells exposed to a methanolic coal dust extract.

    PubMed

    Guerrero-Castilla, Angelica; Olivero-Verbel, Jesus

    2014-11-01

    Exposure to coal dust has been associated with different chronic diseases and mortality risk. This airborne pollutant is produced during coal mining and transport activities, generating environmental and human toxicity. The aim of this study was to determine the effects of a coal dust methanolic extract on HepG2, a human liver hepatocellular carcinoma cell line. Cells were exposed to 5-100ppm methanolic coal extract for 12h, using DMSO as control. MTT and comet assays were used for the evaluation of cytotoxicity and genotoxicity, respectively. Real time PCR was utilized to quantify relative expression of genes related to oxidative stress, xenobiotic metabolism and DNA damage. Coal extract concentrations did not induce significant changes in HepG2 cell viability after 12h exposure; however, 50 and 100ppm of the coal extract produced a significant increase in genetic damage index with respect to negative control. Compared to vehicle control, mRNA CYP1A1 (up to 163-fold), NQO1 (up to 4.7-fold), and GADD45B (up to 4.7-fold) were up regulated, whereas PRDX1, SOD, CAT, GPX1, XPA, ERCC1 and APEX1 remained unaltered. This expression profile suggests that cells exposed to coal dust extract shows aryl hydrocarbon receptor-mediated alterations, changes in cellular oxidative status, and genotoxic effects. These findings share some similarities with those observed in liver of mice captured near coal mining areas, and add evidence that living around these industrial operations may be negatively impacting the biota and human health.

  10. [Biological properties of Caski cell lines induced by exposing to the space environment].

    PubMed

    Yang, Cheng; Li, Guan-cheng; Li, Yue-hui; Hu, Jin-yue; Xiao, Yan; Zhang, Zhi-jie

    2007-06-01

    To investigate the biological properties of Caski cell lines induced by exposing to the space environment. Caski cells were carried in "Shen Zhou IV" airship. After 7 days of spaceflight, cells survived and were monocoloned, and the experimental methods such as cell morphological observation, the cell proliferation assay, flow cytometry cell cycle analysis, the soft agar assay, and tumorigenesis assay were used to analyze cell growth characteristics and malignant phenotypes. Altogether 1440 strains subclonal cell lines were established and 4 strains were screened. Compared with the control group, mutated cells appeared to have multiple cell morphological changes. Strains numbered 44F10 and 17E3 were screened due to their increased cell proliferation and tumorigenesis, and their cell cycles were induced to progress from G(1) to S phase, while strains 48A9 and 31F2 were opposite to 44F10 and 17E3 in cytological events. The average population double time of ground nomal control group, ground simulant control group, strains numbered 44F10, 17E3, 48A9 and 31F2 groups were 56.54, 58.44, 52.96, 51.46, 101.76 and 88.47h, respectively; compared with the control group, the average double time of strains numbered 44F10 and 17E3 was decline, but with no statistical significance. However, compared with the control groups, the average double time of 48A9 and 31F2 was significant increased (P<0.05). The colony formation rates were 9.7%, 9.3%, 14.7%, 12.1%, 0 and 0.1%, respectively, and the difference between the ground control groups and the other groups was significant (P<0.01); 6 groups of above-mentioned Caski cells were inoculated subcutaneously in Babl/c nude mice respectively. Forty-seven days later, the formed tumors in the nude mice were statistically analyzed and tested. The average weight of tumors of the above-mentioned groups was 0.066, 0.066, 0.175, 0.249, 0.011 and 0.018g. The difference between the ground control groups and other groups was significant (P<0

  11. Genotoxic Changes to Rodent Cells Exposed in Vitro to Tungsten, Nickel, Cobalt and Iron

    PubMed Central

    Bardack, Stephanie; Dalgard, Clifton L.; Kalinich, John F.; Kasper, Christine E.

    2014-01-01

    Tungsten-based materials have been proposed as replacements for depleted uranium in armor-penetrating munitions and for lead in small-arms ammunition. A recent report demonstrated that a military-grade composition of tungsten, nickel, and cobalt induced a highly-aggressive, metastatic rhabdomyosarcoma when implanted into the leg muscle of laboratory rats to simulate a shrapnel wound. The early genetic changes occurring in response to embedded metal fragments are not known. In this study, we utilized two cultured rodent myoblast cell lines, exposed to soluble tungsten alloys and the individual metals comprising the alloys, to study the genotoxic effects. By profiling cell transcriptomes using microarray, we found slight, yet distinct and unique, gene expression changes in rat myoblast cells after 24 h metal exposure, and several genes were identified that correlate with impending adverse consequences of ongoing exposure to weapons-grade tungsten alloy. These changes were not as apparent in the mouse myoblast cell line. This indicates a potential species difference in the cellular response to tungsten alloy, a hypothesis supported by current findings with in vivo model systems. Studies examining genotoxic-associated gene expression changes in cells from longer exposure times are warranted. PMID:24619124

  12. Genotoxic changes to rodent cells exposed in vitro to tungsten, nickel, cobalt and iron.

    PubMed

    Bardack, Stephanie; Dalgard, Clifton L; Kalinich, John F; Kasper, Christine E

    2014-03-10

    Tungsten-based materials have been proposed as replacements for depleted uranium in armor-penetrating munitions and for lead in small-arms ammunition. A recent report demonstrated that a military-grade composition of tungsten, nickel, and cobalt induced a highly-aggressive, metastatic rhabdomyosarcoma when implanted into the leg muscle of laboratory rats to simulate a shrapnel wound. The early genetic changes occurring in response to embedded metal fragments are not known. In this study, we utilized two cultured rodent myoblast cell lines, exposed to soluble tungsten alloys and the individual metals comprising the alloys, to study the genotoxic effects. By profiling cell transcriptomes using microarray, we found slight, yet distinct and unique, gene expression changes in rat myoblast cells after 24 h metal exposure, and several genes were identified that correlate with impending adverse consequences of ongoing exposure to weapons-grade tungsten alloy. These changes were not as apparent in the mouse myoblast cell line. This indicates a potential species difference in the cellular response to tungsten alloy, a hypothesis supported by current findings with in vivo model systems. Studies examining genotoxic-associated gene expression changes in cells from longer exposure times are warranted.

  13. Ultrastructure and calcium balance in meristem cells of pea roots exposed to extremely low magnetic fields

    NASA Astrophysics Data System (ADS)

    Belyavskaya, N. A.

    2001-01-01

    Investigations of low magnetic field (LMF) effects on biological systems have attracted attention of biologists due to planned space flights to other planets where the field intensity does not exceed 10 -5 Oe. Pea ( Pisum sativum L.) seeds were grown in an environment of LMF 3 days. In meristem cells of roots exposed to LMF, one could observe such ultrastructural peculiarities as a noticeable accumulation of lipid bodies, development of a lytic compartment (vacuoles, cytosegresomes and paramural bodies), and reduction of phytoferritin in plastids. Mitochondria were the most sensitive organelle to LMF application. Their size and relative volume in cells increased, matrix was electron-transparent, and cristae reduced. Because of the significant role of calcium signalling in plant responses to different environmental factors, calcium participation in LMF effects was investigated using a pyroantimonate method to identify the localization of free calcium ions. The intensity of cytochemical reaction in root cells after LMF application was strong. The Ca 2+ pyroantimonate deposits were observed both in all organelles and in a hyaloplasm of the cells. Data obtained suggest that the observed LMF effects on ultrastructure of root cells were due to disruptions in different metabolic systems including effects on Ca 2+ homeostasis.

  14. Proteomic Analysis of Primary Human Airway Epithelial Cells Exposed to the Respiratory Toxicant Diacetyl.

    PubMed

    Foster, Matthew W; Gwinn, William M; Kelly, Francine L; Brass, David M; Valente, Ashlee M; Moseley, M Arthur; Thompson, J Will; Morgan, Daniel L; Palmer, Scott M

    2017-02-03

    Occupational exposures to the diketone flavoring agent, diacetyl, have been associated with bronchiolitis obliterans, a rare condition of airway fibrosis. Model studies in rodents have suggested that the airway epithelium is a major site of diacetyl toxicity, but the effects of diacetyl exposure upon the human airway epithelium are poorly characterized. Here we performed quantitative LC-MS/MS-based proteomics to study the effects of repeated diacetyl vapor exposures on 3D organotypic cultures of human primary tracheobronchial epithelial cells. Using a label-free approach, we quantified approximately 3400 proteins and 5700 phosphopeptides in cell lysates across four independent donors. Altered expression of proteins and phosphopeptides were suggestive of loss of cilia and increased squamous differentiation in diacetyl-exposed cells. These phenomena were confirmed by immunofluorescence staining of culture cross sections. Hyperphosphorylation and cross-linking of basal cell keratins were also observed in diacetyl-treated cells, and we used parallel reaction monitoring to confidently localize and quantify previously uncharacterized sites of phosphorylation in keratin 6. Collectively, these data identify numerous molecular changes in the epithelium that may be important to the pathogenesis of flavoring-induced bronchiolitis obliterans. More generally, this study highlights the utility of quantitative proteomics for the study of in vitro models of airway injury and disease.

  15. Bacterial cells exposed to nanosecond pulsed electric fields show lethal and sublethal effects.

    PubMed

    Perni, S; Chalise, P R; Shama, G; Kong, M G

    2007-12-15

    Cell suspensions of Escherichia coli K12 and Salmonella typhimurium were exposed to electrical pulses of 32 ns duration at a field intensity of 100 kV/cm and a repetition rate of 30 pulses per second for a total of 300 s. Treated cells were plated onto Tryptone Soya Agar (TSA) and TSA supplemented with NaCl, and cell counts were monitored daily for 3 days. The concentrations of NaCl used were 3 and 4% (w/v) for E. coli and 4 and 5% (w/v) for S. typhimurium. Treatment under these conditions resulted in a 2 log(10) reduction for E. coli and approximately a single log(10) reduction for S. typhimurium. For both species of bacteria it was discovered that the surviving population was composed of only 1% of uninjured cells. Moreover, the proportion of sublethally injured cells increased more rapidly than the total recoverable population suggesting a process of injury accumulation culminating in death rather than an 'all or nothing' mechanism. Sublethal injury manifested itself in a proportion of the injured population of both species by an extended lag phase at longer treatment times. Finally, possible mechanisms by which nanosecond electric pulses inactivate bacteria are discussed.

  16. Endometrial stem cell transplantation in MPTP- exposed primates: an alternative cell source for treatment of Parkinson's disease.

    PubMed

    Wolff, Erin F; Mutlu, Levent; Massasa, Efi E; Elsworth, John D; Eugene Redmond, D; Taylor, Hugh S

    2015-01-01

    Parkinson's disease (PD) is a neurodegenerative disease caused by the loss of dopaminergic neurons in the substantia nigra. Cell-replacement therapies have emerged as a promising strategy to slow down or replace neuronal loss. Compared to other stem cell types, endometrium-derived stem cells (EDSCs) are an attractive source of stem cells for cellular therapies because of their ease of collection and vast differentiation potential. Here we demonstrate that endometrium-derived stem cells may be transplanted into an MPTP exposed monkey model of PD. After injection into the striatum, endometrium-derived stem cells engrafted, exhibited neuron-like morphology, expressed tyrosine hydroxylase (TH) and increased the numbers of TH positive cells on the transplanted side and dopamine metabolite concentrations in vivo. Our results suggest that endometrium-derived stem cells may provide a therapeutic benefit in the primate model of PD and may be used in stem cell based therapies. © 2014 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

  17. Linking NE1545 gene expression with cell volume changes in Nitrosomonas europaea cells exposed to aromatic hydrocarbons.

    PubMed

    Radniecki, Tyler S; Gilroy, Caslin A; Semprini, Lewis

    2011-01-01

    Nitrosomonas europaea, a model ammonia oxidizing bacterium, was exposed to a wide variety of aromatic hydrocarbons in 3 h batch assays. The expression of NE1545, a phenol sentinel gene involved in fatty acid metabolism, was monitored via quantitative real-time polymerase chain reaction (qRT-PCR) and a Coulter Counter technique was used to monitor changes in cell volume. Decreases in cell volume and NE1545 gene expression correlated strongly with exposure to aromatic hydrocarbons that possessed a single polar group substitution (e.g. phenol and aniline). Aromatic hydrocarbons that contain no polar group substitutions (e.g. toluene) or multiple polar group substitutions (e.g. p-hydroquinone) caused negligible changes in NE1545 expression and cell volume. The oxidation of aromatic hydrocarbons by N. europaea from configurations without a single polar group to one with two polar groups (e.g. p-cresol oxidized to 4-hydroxybenzyl alcohol) and from configurations with no polar groups to one with a single polar group (e.g. ethylbenzene oxidized to 4-ethylphenol) greatly influenced NE1545 gene expression and observed changes in cell volume. Nitrification inhibition in N. europaea by the aromatic hydrocarbons was found to be completely reversible; however, the decreases in cell volume were not reversible suggesting a physical change in cell membrane composition. Ammonia monooxygenase blocking studies showed that the chemical exposure that was responsible for the cell volume decrease and up-regulation in gene expression and not the observed inhibition. N. europaea is the first bacterium shown to experience significant changes in cell volume when exposed to μM concentrations of aromatic hydrocarbons, three orders of magnitude lower than previous studies with other bacteria.

  18. [An immunocytochemical study of the C-cell function of the thyroid in rats exposed on the Kosmos-2044 biosatellite].

    PubMed

    Loginov, V I

    1993-01-01

    Immunocytochemical analysis of thyroid gland C-cells of the rats exposed to a 14-day space flight revealed a decrease in the number of C-cells, volume of their nuclei and a declined percentage of active secretory C-cells, which point to a decline of calcitonin proactive and calcitonin secretory hypofunction of the thyroid C-cells system in flown rats. Tail suspension as a microgravity model caused similar changes in C-cells.

  19. Iron-dependent cell death of hepatocellular carcinoma cells exposed to sorafenib.

    PubMed

    Louandre, Christophe; Ezzoukhry, Zakaria; Godin, Corinne; Barbare, Jean-Claude; Mazière, Jean-Claude; Chauffert, Bruno; Galmiche, Antoine

    2013-10-01

    The multikinase inhibitor sorafenib is currently the treatment of reference for advanced hepatocellular carcinoma (HCC). In our report, we examined the cytotoxic effects of sorafenib on HCC cells. We report that the depletion of the intracellular iron stores achieved by using the iron chelator deferoxamine (DFX) strikingly protects HCC cells from the cytotoxic effects of sorafenib. The protective effect of the depletion of intracellular iron stores could not be explained by an interference with conventional forms of programmed cell death, such as apoptosis or autophagic cell death. We also found that DFX did not prevent sorafenib from reaching its intracellular target kinases. Instead, the depletion of intracellular iron stores prevented sorafenib from inducing oxidative stress in HCC cells. We examined the possibility that sorafenib might exert a cytotoxic effect that resembles ferroptosis, a form of cell death in which iron-dependent oxidative mechanisms play a pivotal role. In agreement with this possibility, we found that pharmacological inhibitors (ferrostatin-1) and genetic procedures (RNA interference against IREB-2) previously reported to modulate ferroptosis, readily block the cytotoxic effects of sorafenib in HCC cells. Collectively, our findings identify ferroptosis as an effective mechanism for the induction of cell death in HCC. Ferroptosis could potentially become a goal for the medical treatment of HCC, thus opening new avenues for the optimization of the use of sorafenib in these tumors.

  20. Exosomes are released by bystander cells exposed to radiation-induced biophoton signals: Reconciling the mechanisms mediating the bystander effect.

    PubMed

    Le, Michelle; Fernandez-Palomo, Cristian; McNeill, Fiona E; Seymour, Colin B; Rainbow, Andrew J; Mothersill, Carmel E

    2017-01-01

    The objective of our study was to explore a possible molecular mechanism by which ultraviolet (UV) biophotons could elicit bystander responses in reporter cells and resolve the problem of seemingly mutually exclusive mechanisms of a physical UV signal & a soluble factor-mediated bystander signal. The human colon carcinoma cell line, HCT116 p53 +/+, was directly irradiated with 0.5 Gy tritium beta particles to induce ultraviolet biophoton emission. Bystander cells were not directly irradiated but were exposed to the emitted UV biophotons. Medium was subsequently harvested from UV-exposed bystander cells. The exosomes extracted from this medium were incubated with reporter cell populations. These reporter cells were then assayed for clonogenic survival and mitochondrial membrane potential with and without prior treatment of the exosomes with RNase. Clonogenic cell survival was significantly reduced in reporter cells incubated with exosomes extracted from cells exposed to secondarily-emitted UV. These exosomes also induced significant mitochondrial membrane depolarization in receiving reporter cells. Conversely, exosomes extracted from non-UV-exposed cells did not produce bystander effects in reporter cells. The treatment of exosomes with RNase prior to their incubation with reporter cells effectively abolished bystander effects in reporter cells and this suggests a role for RNA in mediating the bystander response elicited by UV biophotons and their produced exosomes. This study supports a role for exosomes released from UV biophoton-exposed bystander cells in eliciting bystander responses and also indicates a reconciliation between the UV-mediated bystander effect and the bystander effect which has been suggested in the literature to be mediated by soluble factors.

  1. Exosomes are released by bystander cells exposed to radiation-induced biophoton signals: Reconciling the mechanisms mediating the bystander effect

    PubMed Central

    Fernandez-Palomo, Cristian; McNeill, Fiona E.; Seymour, Colin B.; Rainbow, Andrew J.; Mothersill, Carmel E.

    2017-01-01

    Objective The objective of our study was to explore a possible molecular mechanism by which ultraviolet (UV) biophotons could elicit bystander responses in reporter cells and resolve the problem of seemingly mutually exclusive mechanisms of a physical UV signal & a soluble factor-mediated bystander signal. Methods The human colon carcinoma cell line, HCT116 p53 +/+, was directly irradiated with 0.5 Gy tritium beta particles to induce ultraviolet biophoton emission. Bystander cells were not directly irradiated but were exposed to the emitted UV biophotons. Medium was subsequently harvested from UV-exposed bystander cells. The exosomes extracted from this medium were incubated with reporter cell populations. These reporter cells were then assayed for clonogenic survival and mitochondrial membrane potential with and without prior treatment of the exosomes with RNase. Results Clonogenic cell survival was significantly reduced in reporter cells incubated with exosomes extracted from cells exposed to secondarily-emitted UV. These exosomes also induced significant mitochondrial membrane depolarization in receiving reporter cells. Conversely, exosomes extracted from non-UV-exposed cells did not produce bystander effects in reporter cells. The treatment of exosomes with RNase prior to their incubation with reporter cells effectively abolished bystander effects in reporter cells and this suggests a role for RNA in mediating the bystander response elicited by UV biophotons and their produced exosomes. Conclusion This study supports a role for exosomes released from UV biophoton-exposed bystander cells in eliciting bystander responses and also indicates a reconciliation between the UV-mediated bystander effect and the bystander effect which has been suggested in the literature to be mediated by soluble factors. PMID:28278290

  2. PD-L2 induction on dendritic cells exposed to Mycobacterium avium downregulates BCG-specific T cell response.

    PubMed

    Mendoza-Coronel, Elizabeth; Camacho-Sandoval, Rosa; Bonifaz, Laura C; López-Vidal, Yolanda

    2011-01-01

    The exposure to certain species of Nontuberculous Mycobacteria (NTM) can modulate the immune response induced by Mycobacterium bovis BCG. Mycobacterium avium has been postulated as a weak inducer of dendritic cell (DC) maturation. However, how the DC exposure to M. avium could contribute to the modulation of a BCG-specific CD4+ T cell response and the molecules involved remain unknown. Here, we exposed bone marrow-derived DCs (BMDCs) to M. avium either prior to exposure to BCG or as a unique stimulus. We found that M. avium induces high expression of PD-L2 (B7-DC) in BMDCs. This was dependent on IL-10 production through the TLR2-p38 MAPK signaling pathway. Exposure to M. avium prior to BCG results in BMDCs that do not express co-stimulatory molecules and pro-inflammatory cytokines, while the expression of PD-L2 and IL-10 was maintained. BMDCs exposed to M. avium impaired the activation of BCG-specific T cells through the PD-1: PD-L interaction. This suggests that a M. avium-induced phenotype in DCs might be implicated in the induction of mechanisms of tolerance that could impact the T cell response induced by BCG vaccination.

  3. DNA damage and metallothionein synthesis in human hepatoma cells (HepG2) exposed to cadmium.

    PubMed

    Fatur, T; Tusek, M; Falnoga, I; Scancar, J; Lah, T T; Filipic, M

    2002-08-01

    Cadmium is an important heavy metal environmental toxicant, which is classified as a human carcinogen. The comet assay was used to evaluate the levels of DNA damage in a metabolically competent HepG2 cell line after treatment with low, non-cytotoxic and physiologically relevant concentrations of cadmium, alone and in combination with the dietary mutagen 2-amino-3-methyl-imidazo[4,5-f]quinoline (IQ) and with the environmental mutagen benzo[a]pyrene (B(a)P). After exposure of the cells to 10, 100 and 1000 nM CdCl(2), a dose- and time-dependent increase of DNA damage was detected. Maximal damage was found after 12 h of treatment, but declined with further incubation with CdCl(2). The increased synthesis of metallothioneins on exposure to CdCl(2) up to 12 h suggests that they are responsible for the adaptation of HepG2 cells to the DNA damaging effects of CdCl(2). Co-treatment of the cells with CdCl(2) (10-1000 nM) and IQ (300 microM) induced a dose-dependent increase of DNA damage compared to cells treated with IQ alone. Co-genotoxic activity was also observed by increased formation of micronuclei in cells exposed to IQ and 1000 nM CdCl(2); at this concentration, CdCl(2) alone also induced micronuclei in HepG2 cells. Our results support the hypothesis that direct and indirect mechanisms are involved in cadmium-induced DNA damage.

  4. Calcium dependent and independent cytokine synthesis by air pollution particle-exposed human bronchial epithelial cells

    SciTech Connect

    Sakamoto, Noriho; Hayashi, Shizu; Gosselink, John; Ishii, Hiroshi; Ishimatsu, Yuji; Mukae, Hiroshi; Hogg, James C.; Eeden, Stephan F. van

    2007-12-01

    Exposure to ambient air pollution particles with a diameter of < 10 {mu}m (PM{sub 10}) has been associated with increased cardiopulmonary morbidity and mortality. We have shown that human bronchial epithelial cells (HBECs) exposed to PM{sub 10} produce pro-inflammatory mediators that contribute to a local and systemic inflammatory response. Changes in intracellular calcium concentrations ([Ca{sup 2+}]{sub i}) have been demonstrated to regulate several functions of the airway epithelium including the production of pro-inflammatory mediators. The aim of the present study was to determine the nature and mechanism of calcium responses induced by PM{sub 10} in HBECs and its relationship to cytokine synthesis. Methods: Primary HBECs were exposed to urban air pollution particles (EHC-93) and [Ca{sup 2+}]{sub i} responses were measured using the fluoroprobe (Fura-2). Cytokine levels were measured at mRNA and protein levels using real-time PCR and ELISA. Results: PM{sub 10} increased [Ca{sup 2+}]{sub i} in a dose-dependent manner. This calcium response was reduced by blocking the influx of calcium into cells (i.e. calcium-free medium, NiCl{sub 2}, LaCl{sub 3}). PM{sub 10} also decreased the activity of calcium pumps. PM{sub 10} increased the production of IL-1{beta}, IL-8, GM-CSF and LIF. Preincubation with intracellular calcium chelator (BAPTA-AM) attenuated IL-1{beta} and IL-8 production, but not GM-CSF and LIF production. Conclusion: We conclude that exposure to PM{sub 10} induces an increase in cytosolic calcium and cytokine production in bronchial epithelial cells. Our results also suggest that PM{sub 10} induces the production of pro-inflammatory mediators via either intracellular calcium-dependent (IL-1{beta}, IL-8) or -independent (GM-CSF, LIF) pathways.

  5. Global gene expression profiling in human lung cells exposed to cobalt

    PubMed Central

    Malard, Veronique; Berenguer, Frederic; Prat, Odette; Ruat, Sylvie; Steinmetz, Gerard; Quemeneur, Eric

    2007-01-01

    Background It has been estimated that more than 1 million workers in the United States are exposed to cobalt. Occupational exposure to 59 Co occurs mainly via inhalation and leads to various lung diseases. Cobalt is classified by the IARC as a possible human carcinogen (group 2B). Although there is evidence for in vivo and in vitro toxicity, the mechanisms of cobalt-induced lung toxicity are not fully known. The purpose of this work was to identify potential signatures of acute cobalt exposure using a toxicogenomic approach. Data analysis focused on some cellular processes and protein targets that are thought to be relevant for carcinogenesis, transport and biomarker research. Results A time course transcriptome analysis was performed on A549 human pulmonary cells, leading to the identification of 85 genes which are repressed or induced in response to soluble 59 Co. A group of 29 of these genes, representing the main biological functions, was assessed by quantitative RT-PCR. The expression profiles of six of them were then tested by quantitative RT-PCR in a time-dependent manner and three modulations were confirmed by Western blotting. The 85 modulated genes include potential cobalt carriers (FBXL2, ZNT1, SLC12A5), tumor suppressors or transcription factors (MAZ, DLG1, MYC, AXL) and genes linked to the stress response (UBC, HSPCB, BNIP3L). We also identified nine genes coding for secreted proteins as candidates for biomarker research. Of those, TIMP2 was found to be down-regulated and this modulation was confirmed, in a dose-dependent manner, at protein level in the supernatant of exposed cells. Conclusion Most of these genes have never been described as related to cobalt stress and provide original hypotheses for further study of the effects of this metal ion on human lung epithelial cells. A putative biomarker of cobalt toxicity was identified. PMID:17553155

  6. The ADMA/DDAH/NO pathway in human vein endothelial cells exposed to arsenite.

    PubMed

    Osorio-Yáñez, Citlalli; Chin-Chan, Miguel; Sánchez-Peña, Luz C; Atzatzi-Aguilar, Octavio G; Olivares-Reyes, Jesus A; Segovia, José; Del Razo, Luz M

    2017-08-01

    Inorganic arsenic (iAs) exposure is related to cardiovascular disease, which is characterized by endothelial dysfunction and nitric oxide (NO) depletion. The mechanisms underlying NO depletion as related to iAs exposure are not fully understood. The endogenous inhibitor of nitric oxide synthase, asymmetric dimethylarginine (ADMA), might be a molecular target of iAs. ADMA concentrations are regulated by proteins involved in its synthesis (arginine methyl transferase 1 [PRMT-1]) and degradation (dimethylarginine dimethylaminohydrolase [DDAH]). Both, ADMA and NO are susceptible to oxidative stress. We aimed to determine the ADMA/DDAH/NO pathway in human vein endothelial cells (HUVEC-CS) exposed to arsenite. We exposed HUVEC-CS cells to 1, 2.5 and 5μM of arsenite for 24h. We proved that arsenite at 5μM was able to decrease NO levels with an associated increase in ADMA and depletion of l-arginine in HUVEC-CS cells. We also found a decrease in DDAH-1 protein expression with 5μM of arsenite compared to the control group. However, we did not observe significant differences in PRMT-1 protein expression at any of the concentrations of arsenite employed. Finally, arsenite (2.5 and 5μM) increased NADPH oxidase 4 protein levels compared with the control group. We conclude that ADMA, l-arginine and DDAH are involved in NO depletion produced by arsenite, and that the mechanism is related to oxidative stress. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. The protective effect of curcumin in Olfactory Ensheathing Cells exposed to hypoxia.

    PubMed

    Bonfanti, Roberta; Musumeci, Teresa; Russo, Cristina; Pellitteri, Rosalia

    2017-02-05

    Curcumin, a phytochemical component derived from the rhizomes of Curcuma longa, has shown a great variety of pharmacological activities, such as anti-inflammatory, anti-tumor, anti-depression and anti-oxidant activity. Therefore, in the last years it has been used as a therapeutic agent since it confers protection in different neurodegenerative diseases, cerebral ischemia and excitotoxicity. Olfactory Ensheathing Cells (OECs) are glial cells of the olfactory system. They are able to secrete several neurotrophic growth factors, promote axonal growth and support the remyelination of damaged axons. OEC transplantation has emerged as a possible experimental therapy to induce repair of spinal cord injury, even if the functional recovery is still limited. Since hypoxia is a secondary effect in spinal cord injury, this in vitro study investigates the protective effect of curcumin in OECs exposed to hypoxia. Primary OECs were obtained from neonatal rat olfactory bulbs and placed both in normal and hypoxic conditions. Furthermore, some cells were grown with basic Fibroblast Growth Factor (bFGF) and/or curcumin at different concentration and times. The results obtained through immunocytochemical procedures and MTT test show that curcumin stimulates cell viability in OECs grown in normal and hypoxic conditions. Furthermore, the synergistic effect of curcumin and bFGF is the most effective exerting protection on OECs. Since spinal cord injury is often accompanied by secondary insults, such as ischemia or hypoxia, our results suggest that curcumin in combination with bFGF might be considered a possible approach for restoration in injuries.

  8. Expression of potentially lethal damage in Chinese hamster cells exposed to hematoporphyrin derivative photodynamic therapy.

    PubMed

    Gomer, C J; Rucker, N; Ferrario, A; Murphree, A L

    1986-07-01

    Experiments were performed to determine whether the expression and/or repair of potentially lethal damage could be observed in mammalian cells exposed to hemataporphyrin derivative (HPD) photodynamic therapy (PDT). Photodynamic therapy was combined with posttreatment protocols known to inhibit the repair of potentially lethal damage in cells treated with X-rays, ultraviolet radiation, or alkylating agents. Potentiation of lethal damage from photodynamic therapy was induced by hypothermia (4 degrees C) following short (1 h) or extended (16 h) HPD incubation conditions. Caffeine potentiated the lethal effects of PDT only when cells were incubated with HPD for extended time periods. However, 3-aminobenzamide had no effect on the cytotoxic actions of PDT following either short or extended HPD incubations. Recovery from potentially lethal damage expressed by posttreatment hypothermia was complete within 1 h, while recovery from potentially lethal damage expressed by posttreatment caffeine required time periods of up to 24 h. The lack of effect of 3-aminobenzamide on expression of potentially lethal damage following photodynamic therapy may be related to direct inhibition of adenosine diphosphoribose transferase by photodynamic therapy. These results indicate that the expression and repair of potentially lethal damage can be observed in cells treated with PDT and will vary as a function of porphyrin incubation conditions.

  9. Mycobacterium tuberculosis genome-wide screen exposes multiple CD8+ T cell epitopes

    PubMed Central

    Hammond, A S; Klein, M R; Corrah, T; Fox, A; Jaye, A; McAdam, K P; Brookes, R H

    2005-01-01

    Mounting evidence suggests human leucocyte antigen (HLA) class I-restricted CD8+ T cells play a role in protective immunity against tuberculosis yet relatively few epitopes specific for the causative organism, Mycobacterium tuberculosis, are reported. Here a total genome-wide screen of M. tuberculosis was used to identify putative HLA-B*3501 T cell epitopes. Of 479 predicted epitopes, 13 with the highest score were synthesized and used to restimulate lymphocytes from naturally exposed HLA-B*3501 healthy individuals in cultured and ex vivo enzyme-linked immunospot (ELISPOT) assays for interferon (IFN)-γ. All 13 peptides elicited a response that varied considerably between individuals. For three peptides CD8+ T cell lines were expanded and four of the 13 were recognized permissively through the HLA-B7 supertype family. Although further testing is required we show the genome-wide screen to be feasible for the identification of unknown mycobacterial antigens involved in immunity against natural infection. While the mechanisms of protective immunity against M. tuberculosis infection remain unclear, conventional class I-restricted CD8+ T cell responses appear to be widespread throughout the genome. PMID:15762882

  10. Inflammatory Cytokine Gene Expression in THP-1 Cells Exposed to Stachybotrys chartarum and Aspergillus versicolor

    PubMed Central

    Pei, Ruoting; Gunsch, Claudia K.

    2013-01-01

    Very little is known about the mechanisms which occur in human cells upon exposure to fungi as well as their mycotoxins. A better understanding of toxin-regulated gene expression would be helpful to identify safe levels of exposure and could eventually be the basis for establishing guidelines for remediation scenarios following a water intrusion event. In this research, cytokine mRNA expression patterns were investigated in the human monocytic THP-1 cell line exposed to fungal extracts of various fragment sizes obtained from Stachybotrys chartarum RTI 5802 and/or Aspergillus versicolor RTI 3843, two common and well studied mycotoxin producing fungi. Cytokine mRNA expression was generally upregulated 2 to 10 times following a 24-hour exposure to fungal extracts. Expression of the proinflammatory interleukin-1β (IL-1β), Interleukin-8 (IL-8) and tumor necrosis factor-α (TNFα) genes increased while the anti-inflammatory gene Interleukin-10 (IL-10) also increased albeit at very low level, suggesting that negative feedback regulation mechanism of production of pro-inflammatory cytokines initiated upon 24 hours of incubation. In addition, submicron size extracts of A. versicolor caused significant death of THP-1 cells whereas extracts of S. chartarum caused no cell death while the mixture of the two fungi had an intermediate effect. There was no general correlation between gene expression and fragment sizes, which suggests that all submicron fragments may contribute to inflammatory response. PMID:21384497

  11. Inflammatory cytokine gene expression in THP-1 cells exposed to Stachybotrys chartarum and Aspergillus versicolor.

    PubMed

    Pei, Ruoting; Gunsch, Claudia K

    2013-01-01

    Very little is known about the mechanisms that occur in human cells upon exposure to fungi as well as their mycotoxins. A better understanding of toxin-regulated gene expression would be helpful to identify safe levels of exposure and could eventually be the basis for establishing guidelines for remediation scenarios following a water intrusion event. In this research, cytokine mRNA expression patterns were investigated in the human monocytic THP-1 cell line exposed to fungal extracts of various fragment sizes obtained from Stachybotrys chartarum RTI 5802 and/or Aspergillus versicolor RTI 3843, two common and well-studied mycotoxin producing fungi. Cytokine mRNA expression was generally upregulated 2-10 times following a 24 h exposure to fungal extracts. Expression of the proinflammatory interleukin-1β, interleukin-8, and tumor necrosis factor-α genes increased while the anti-inflammatory gene interleukin-10 also increased albeit at very low level, suggesting that negative feedback regulation mechanism of production of proinflammatory cytokines initiated upon 24 h of incubation. In addition, submicron size extracts of A. versicolor caused significant death of THP-1 cells, whereas extracts of S. chartarum caused no cell death while the mixture of the two fungi had an intermediate effect. There was no general correlation between gene expression and fragment sizes, which suggests that all submicron fragments may contribute to inflammatory response. Copyright © 2011 Wiley Periodicals, Inc.

  12. Human epithelial cells exposed to functionalized multiwalled carbon nanotubes: interactions and cell surface modifications.

    PubMed

    Fanizza, C; Casciardi, S; Incoronato, F; Cavallo, D; Ursini, C L; Ciervo, A; Maiello, R; Fresegna, A M; Marcelloni, A M; Lega, D; Alvino, A; Baiguera, S

    2015-09-01

    With the expansion of the production and applications of multiwalled carbon nanotubes (MWCNTs) in several industrial and science branches, the potential adverse effects on human health have attracted attention. Numerous studies have been conducted to evaluate how chemical functionalization may affect MWCNT effects; however, controversial data have been reported, showing either increased or reduced toxicity. In particular, the impact of carboxylation on MWCNT cytotoxicity is far from being completely understood. The aim of this work was the evaluation of the modifications induced by carboxylated-MWCNTs (MWCNTs-COOH) on cell surface and the study of cell-MWCNT-COOH interactions by means of field emission scanning electron microscope (FESEM). Human pulmonary epithelial cells (A549) were incubated with MWCNTs-COOH for different exposure times and concentrations (10 μg/mL for 1, 2, 4 h; 5, 10, 20 μg/mL for 24 h). At short incubation time, MWCNTs-COOH were easily observed associated with plasma membrane and in contact with microvilli. After 24 h exposure, FESEM analysis revealed that MWCNTs-COOH induced evident changes in the cellular surface in comparison to control cells: treated cells showed blebs, holes and a depletion of the microvilli density in association with structure modifications, such as widening and/or lengthening. In particular, an increase of cells showing holes and microvilli structure alterations was observed at 20 μg/mL concentration. FESEM analysis showed nanotube agglomerates, of different sizes, entering into the cell with two different mechanisms: inward bending of the membrane followed by nanotube sinking, and nanotube internalization directly through holes. The observed morphological microvilli modifications, induced by MWCNTs-COOH, could affect epithelial functions, such as the control of surfactant production and secretion, leading to pathological conditions, such as alveolar proteinosis. More detailed studies will be, however, necessary to

  13. Folic acid supplementation affects apoptosis and differentiation of embryonic neural stem cells exposed to high glucose.

    PubMed

    Jia, De-yong; Liu, Hui-juan; Wang, Fu-wu; Liu, Shang-ming; Ling, Eng-Ang; Liu, Kai; Hao, Ai-jun

    2008-07-25

    Folic acid (FA) supplementation has been shown to be extremely effective in reducing the occurrence of neural tube defects (NTDs), one of the most common birth defects associated with diabetic pregnancy. However, the antiteratogenic mechanism of FA in diabetes-induced NTDs is unclear. This study investigated the neuroprotective mechanism of FA in neural stem cells (NSCs) exposed to high glucose in vitro. The undifferentiated or differentiated NSCs were cultured in normal D-glucose concentration (NG) or high D-glucose concentration (HG) with or without FA. FA supplementation significantly decreased apoptosis induced by HG and lowered the expression of p53 in the nucleus of undifferentiated NSCs exposed to HG. Administration of FA in differentiated NSCs did not alter their precocious differentiation induced by HG. The increased mRNA expression levels of the basic helix-loop-helix factors including Neurog1, Neurog2, NeuroD2, Mash1, Id1, Id2, and Hes5 in the presence of HG were not significantly affected by FA. The present results provided a cellular mechanism by which FA supplementation may have a potential role in prevention of NTDs in diabetic pregnancies. On the other hand, FA increased the mRNA expression levels of the above transcription factors and accelerated the differentiation of NSCs in the NG medium, suggesting that it may adversely affect the normal differentiation of NSCs. Therefore, the timing and dose of FA would be critical factors in considering FA supplementation in normal maternal pregnancy.

  14. Computerized morphodensitometric analysis of blood cells from individuals exposed to low-dose radiation

    NASA Astrophysics Data System (ADS)

    Kopylov, Victor F.; Zhukotsky, Alexander V.; Kogan, Emmanuil M.; Putina, Tatiana G.; Marchenko, Oleg V.; Lomakina, Elena B.; Chernysh, Sergei A.

    1994-07-01

    This study was carried out as part of the state program Children Affected by the Chernobyl Accident and used materials and results of the medical examinations of children living in radio-contaminated areas of the Bryansk region. The health status of children and adolescents exposed to low-dose radiation is causing increasing concern. Our attention was focused on assessing chromatin disorders in interphase lymphocyte nuclei and determining diagnostic criteria for lymphocytes and erythrocytes through measurement of their morphodensitometric parameters using a system of our own design called DIAMORF. Blood cells from children and adolescents exposed to low-dose radiation were examined after processing images of DNA- stained lymphocytes and unstained erythrocytes in a computer analyzer. The new method was used to study the fine supromolecular structure of the chromatin network. An optoelectronic image analyzer can differentiate between different areas of the erythrocytes surface and determine their curvatures. Parameters of cellular changes in response to low-dose radiation were evaluated quantitatively by measuring the optical density index and a number of other optical and geometric parameters.

  15. Protein kinase C activity in developing rat brain cells exposed to 2.45 GHz radiation.

    PubMed

    Paulraj, R; Behari, J

    2006-01-01

    There is growing concern by the public regarding the potential human health hazard due to exposure to microwave frequencies. 2.45 GHz radiation widespread use in industry, research, and medicine, and leakage into the environment is possible. In order to quantitate this, experiments were performed on developing rat brain. Male Wistar 35-day-old rats (n = 6) were used for this study. Animals were exposed to 2.45 GHz radiation for 2 h/day for a period of 35 days at a power density of 0.344 mW/cm(2) (SAR 0.11 W/kg). The control group was sham irradiated. After 35 days these rats were sacrificed and whole brain tissue was isolated for protein kinase C (PKC) assay. For morphological study the forebrain was isolated from the whole brain and PKC activity was measured using P(32) labeled ATP. Our study reveals a statistically significant (p < 0.05) decrease in PKC activity in hippocampus as compared to the remaining portion of the whole brain and the control group. A similar experiment conducted on hippocampus and the whole brain gave a similar result. Electron microscopic study shows an increase in the glial cell population in the exposed group as compared to the control group. This present study is indicative of a significant change after exposure to the above-mentioned field intensity. This suggests that chronic exposures may affect brain growth and development.

  16. Shift in FTIR spectrum patterns in methomyl-exposed rat spleen cells.

    PubMed

    Suramana, T; Sindhuphak, R; Dusitsin, N; Posayanonda, T; Sinhaseni, P

    2001-04-10

    Methomyl is a highly toxic carbamate insecticide which is widely used in many agricultural countries. We have applied the Fourier-transformed infrared (FTIR) spectroscopic method to study the toxicity of methomyl on cytoskeletal protein and the nucleic acid of rat spleen cells. Rats were given methomyl by gavage at 2, 6 and 8 mg/kg in single doses. Colchicine, a microtubule-disrupting agent, was given to rats at 2, 4, and 6 mg/kg in single doses and mitomycin C, an alkylating agent which acts as a DNA-cross-linking agent, was given by an intraperitoneal route to rats at 1 mg/kg. It was shown that the wavenumber of FTIR spectra at amide I and amide II in both methomyl- and colchicine-exposed rats shifted in dose response manner when compared with the control (P < 0.05). The amide I and II shifts in these regions have been proposed to be the result of an alpha-helix protein conformational change. Toxic doses of mitomycin C, a DNA-cross-linking agent, did not result in this pattern. Moreover, all exposed rats showed an increase in the absorbance ratios that were related to the vibrational mode of the phosphodiester group in nucleic acid (P < 0.05).

  17. Cytogenetic analysis of nasal mucosa cells and lymphocytes from high-level long-term formaldehyde exposed workers and low-level short-term exposed waiters.

    PubMed

    Ye, Xiaolei; Yan, Wensheng; Xie, Hong; Zhao, Meiying; Ying, Chenjiang

    2005-12-07

    The evidence for genotoxic potential of formaldehyde (FA) in humans is insufficient and conflicting. We previously reported a higher frequency of micronuclei in nasal and oral exfoliative cells from students exposed to formaldehyde vapor for short-term. To further evaluate the genetic effects of long-term occupational exposure to FA and short-term exposure to FA of indoor sources, the frequencies of micronuclei (MN) in nasal mucosa cells, sister chromatid exchanges (SCEs) of peripheral lymphocytes, and the lymphocyte subsets were evaluated in 18 non-smoking workers (mean exposure duration was 8.6 years) in an FA factory and 16 non-smoking waiters exposed to FA for 12 weeks in a ballroom. A non-smoking student group without occupational exposure (n=23) to FA was used as control. The 8h time-weighted average (TWA) concentrations of formaldehyde was 0.985+/-0.286 mg/m3 with the ceiling exposure concentration of 1.694 mg/m3 in the workshop, and 0.107+/-0.067 mg/m3 in the ballroom (5 h TWA). Higher frequencies of micronuclei per thousand cells in nasal mucosa cells of workers versus control (2.70+/-1.50 versus 1.25+/-0.65, p<0.05) and higher frequency of SCEs in peripheral lymphocytes of workers group (8.24+/-0.89 versus 6.38+/-0.41, p<0.05) were observed. Increased frequency of micronuclei in nasal mucosa cells or SCE in peripheral lymphocytes was not found among waiters group. The results suggest that the genotoxic potential of high level FA exposure may have occupational risks in long-term exposure groups.

  18. The Bioeffects Resulting from Prokaryotic Cells and Yeast Being Exposed to an 18 GHz Electromagnetic Field

    PubMed Central

    Pham, Vy T. H.; Nguyen, Song Ha; Baulin, Vladimir; Croft, Rodney J.; Phillips, Brian; Crawford, Russell J.

    2016-01-01

    The mechanisms by which various biological effects are triggered by exposure to an electromagnetic field are not fully understood and have been the subject of debate. Here, the effects of exposing typical representatives of the major microbial taxa to an 18 GHz microwave electromagnetic field (EMF)were studied. It appeared that the EMF exposure induced cell permeabilisation in all of the bacteria and yeast studied, while the cells remained viable (94% throughout the exposure), independent of the differences in cell membrane fatty acid and phospholipid composition. The resulting cell permeabilisation was confirmed by detection of the uptake of propidium iodine and 23 nm fluorescent silica nanospheres using transmission electron microscopy (TEM) and confocal laser scanning microscopy (CLSM). Upon EMF exposure, the bacterial cell membranes are believed to become permeable through quasi-endocytosis processes. The dosimetry analysis revealed that the EMF threshold level required to induce the uptake of the large (46 nm) nanopsheres was between three and six EMF doses, with a specific absorption rate (SAR) of 3 kW/kg and 5 kW/kg per exposure, respectively, depending on the bacterial taxa being studied. It is suggested that the taxonomic affiliation and lipid composition (e.g. the presence of phosphatidyl-glycerol and/or pentadecanoic fatty acid) may affect the extent of uptake of the large nanospheres (46 nm). Multiple 18 GHz EMF exposures over a one-hour period induced periodic anomalous increases in the cell growth behavior of two Staphylococcus aureus strains, namely ATCC 25923 and CIP 65.8T. PMID:27391488

  19. The Bioeffects Resulting from Prokaryotic Cells and Yeast Being Exposed to an 18 GHz Electromagnetic Field.

    PubMed

    Nguyen, The Hong Phong; Pham, Vy T H; Nguyen, Song Ha; Baulin, Vladimir; Croft, Rodney J; Phillips, Brian; Crawford, Russell J; Ivanova, Elena P

    2016-01-01

    The mechanisms by which various biological effects are triggered by exposure to an electromagnetic field are not fully understood and have been the subject of debate. Here, the effects of exposing typical representatives of the major microbial taxa to an 18 GHz microwave electromagnetic field (EMF)were studied. It appeared that the EMF exposure induced cell permeabilisation in all of the bacteria and yeast studied, while the cells remained viable (94% throughout the exposure), independent of the differences in cell membrane fatty acid and phospholipid composition. The resulting cell permeabilisation was confirmed by detection of the uptake of propidium iodine and 23 nm fluorescent silica nanospheres using transmission electron microscopy (TEM) and confocal laser scanning microscopy (CLSM). Upon EMF exposure, the bacterial cell membranes are believed to become permeable through quasi-endocytosis processes. The dosimetry analysis revealed that the EMF threshold level required to induce the uptake of the large (46 nm) nanopsheres was between three and six EMF doses, with a specific absorption rate (SAR) of 3 kW/kg and 5 kW/kg per exposure, respectively, depending on the bacterial taxa being studied. It is suggested that the taxonomic affiliation and lipid composition (e.g. the presence of phosphatidyl-glycerol and/or pentadecanoic fatty acid) may affect the extent of uptake of the large nanospheres (46 nm). Multiple 18 GHz EMF exposures over a one-hour period induced periodic anomalous increases in the cell growth behavior of two Staphylococcus aureus strains, namely ATCC 25923 and CIP 65.8T.

  20. Enhanced histamine release from lung mast cells of guinea pigs exposed to sulfuric acid aerosols

    SciTech Connect

    Fujimaki, Hidekazu ); Katayama, Noboru; Wakamori, Kazuo )

    1992-06-01

    To clarify the relationship between air pollution and mast cell response, the effects of sulfuric acid aerosols on histamine release from lung mast cells of guinea pigs were investigated. Guinea pigs were exposed to 0.3, 1.0 and 3.2 mg/m{sup 3} sulfuric acid (H{sub 2}SO{sub 4}) aerosols or 4 ppm nitrogen dioxide (NO{sub 2}) for 2 and 4 weeks. After the exposure, lung mast cell suspensions were isolated by collagenase treatment and antigen- or A23187-induced histamine release was measured. Antigen-induced histamine release from mast cells was significantly enhanced by the exposure to 1.0 and 3.2 mg/m{sup 3} H{sub 2}SO{sub 4} for 2 weeks, but exposure to H{sub 2}SO{sub 4} for 4 weeks did not show the enhancement of antigen-induced histamine release. A23187-induced histamine release was significantly enhanced by the exposure to 1.0 mg/m{sup 3} H{sub 2}SO{sub 4} or 4 ppm NO{sub 2} for 2 weeks, but suppression of histamine release from lung mast cells stimulated with A23187 was observed by the exposure to 3.2 mg/m{sup 3} H{sub 2}So{sub 4} for 4 weeks. The exposure to 0.3 mg/m{sup 3} H{sub 2}So{sub 4} showed no changes in antigen- and A23187-induced histamine release. The combination of 1.0 mg/m{sup 3} H{sub 2}So{sub 4} with 4 ppm NO{sub 2} for 2 weeks resulted in no changes in antigen- and A23187-induced histamine release. These results suggested that functional properties of lung mast cells may be altered by a low concentration of H{sub 2}So{sub 4} aerosol exposure.

  1. Metallothionein-1 as a biomarker of altered redox metabolism in hepatocellular carcinoma cells exposed to sorafenib.

    PubMed

    Houessinon, Aline; François, Catherine; Sauzay, Chloé; Louandre, Christophe; Mongelard, Gaelle; Godin, Corinne; Bodeau, Sandra; Takahashi, Shinichiro; Saidak, Zuzana; Gutierrez, Laurent; Régimbeau, Jean-Marc; Barget, Nathalie; Barbare, Jean-Claude; Ganne, Nathalie; Chauffert, Bruno; Coriat, Romain; Galmiche, Antoine

    2016-05-16

    Sorafenib, a kinase inhibitor active against various solid tumours, induces oxidative stress and ferroptosis, a new form of oxidative necrosis, in some cancer cells. Clinically-applicable biomarkers that reflect the impact of sorafenib on the redox metabolism of cancer cells are lacking. We used gene expression microarrays, real-time PCR, immunoblot, protein-specific ELISA, and gene reporter constructs encoding the enzyme luciferase to study the response of a panel of cancer cells to sorafenib. Tumour explants prepared from surgical hepatocellular carcinoma (HCC) samples and serum samples obtained from HCC patients receiving sorafenib were also used. We observed that genes of the metallothionein-1 (MT1) family are induced in the HCC cell line Huh7 exposed to sorafenib. Sorafenib increased the expression of MT1G mRNA in a panel of human cancer cells, an effect that was not observed with eight other clinically-approved kinase inhibitors. We identified the minimal region of the MT1G promoter that confers inducibility by sorafenib to a 133 base pair region containing an Anti-oxidant Response Element (ARE) and showed the essential role of the transcription factor NRF2 (Nuclear factor erythroid 2-Related Factor 2). We examined the clinical relevance of our findings by analysing the regulation of MT1G in five tumour explants prepared from surgical HCC samples. Finally, we showed that the protein levels of MT1 increase in the serum of some HCC patients receiving sorafenib, and found an association with reduced overall survival. These findings indicate that MT1 constitute a biomarker adapted for exploring the impact of sorafenib on the redox metabolism of cancer cells.

  2. Differentiation of bovine intramuscular and subcutaneous stromal-vascular cells exposed to dexamethasone and troglitazone.

    PubMed

    Grant, A C; Ortiz-Colón, G; Doumit, M E; Tempelman, R J; Buskirk, D D

    2008-10-01

    The objectives of these experiments were to compare differentiation of bovine stromal-vascular (S-V) cells isolated from i.m. and s.c. adipose tissues in response to a glucocorticoid and a peroxisome proliferator-activated receptor gamma agonist. Stromal-vascular cells were isolated from i.m. and s.c. fat depots of 3 Angus steers and propagated in culture. Cells were exposed to differentiation media containing 0.25 microM dexamethasone (DEX), a glucocorticoid analog, and 40 microM troglitazone (TRO), a peroxisome proliferator-activated receptor gamma agonist, or both. Cells treated with DEX and TRO had greater (P < 0.02) glycerol-3-phosphate dehydrogenase activity than control cells. No interactions between DEX, TRO, and depot (P > 0.59) or depot differences (P = 0.41) in glycerol-3-phosphate dehydrogenase activity were found. Morphological assessment of adipogenic colonies showed that DEX induced a 1.8-fold increase in the percentage of adipogenic colonies (P = 0.03), whereas TRO increased the proportion of adipogenic colonies by 1.9-fold (P = 0.02) compared with those not treated with DEX or TRO, respectively. Depots had a similar percentage of adipogenic colonies (P = 0.18); however, the percentage of differentiated cells within adipogenic colonies was found to be 6.4-fold greater in s.c. isolates compared with i.m. (P < 0.001). Addition of TRO increased the proportion of differentiated cells within colonies by 10-fold compared with those of nontreated colonies (P < 0.001), whereas the percentage of differentiated cells within adipogenic colonies only tended to be increased by DEX (P = 0.10). These data indicate that bovine i.m. and s.c. S-V cells are capable of enhanced differentiation in response to DEX and TRO, and these effects were additive. Most importantly, inherent differences in the capacity to differentiate exist between adipogenic bovine i.m. and s.c. S-V cells.

  3. In vitro effects of Ala16Val manganese superoxide dismutase gene polymorphism on human white blood cells exposed to methylmercury.

    PubMed

    Algarve, T D; Barbisan, F; Ribeiro, E E; Duarte, M M M F; Mânica-Cattani, M F; Mostardeiro, C P; Lenz, A F; da Cruz, I B M

    2013-10-29

    Environmental contamination by methylmercury (MeHg) is an enormous public health problem in world regions such as Amazonia. MeHg toxic effects seem to be influenced by environmental and genetic factors. However, few studies have evaluated the genetic influences of MeHg toxicity in humans. Therefore, the aim of this study was to evaluate the genetic influence of Ala16Val manganese superoxide dismutase gene polymorphism (Ala16Val-MnSOD) on the cytotoxic effects of in vitro human leukocytes exposed to MeHg. Subjects were selected from 100 individuals aged 26.4 ± 7.3 years genotyped to Ala16Val-MnSOD polymorphism (AA = 6, VV = 6, and AV = 12) to perform in vitro testing using white blood cells (WBCs). Reactive oxygen species production was measured using 2',7'-dichlorofluorescein diacetate fluorimetric assay, and cell viability was measured using MTT assay on WBC samples from the same subjects that were both exposed and not exposed to MeHg (2.5 µM for 6 h). The results showed that AA- and VV-WBCs exposed to MeHg did not display increased reactive oxygen species levels compared to those in cells that were not exposed. However, AV-leukocytes exposed to MeHg displayed increased ROS levels. Cellular viability comparison among genotypes exposed to MeHg showed that the viability of AA-WBCs was lower than that of VV-WBC, with mean values of 3.46 ± 0.13 and 3.08 ± 0.77 (standard error), respectively (P = 0.033), whereas heterozygous cells (AV) displayed intermediate values. This difference was likely due to the higher basal H2O2 production of AA-WBCs compared to that of other genotypes. These results suggest that the Ala16Val-MnSOD polymorphism has toxicogenetic effects in human cells exposed to MeHg.

  4. Natural Products Mediated Regulation of Oxidative Stress and DNA Damage in Ultraviolet Exposed Skin Cells.

    PubMed

    Farooqi, Ammad A; Li, Ruei-Nian; Huang, Hurng-Wern; Ismail, Muhammad; Yuan, Shyng-Shiou F; Wang, Hui-Min D; Liu, Jing-Ru; Tang, Jen-Yang; Chang, Hsueh-Wei

    2015-01-01

    Data obtained through high-throughput technologies have gradually revealed that a unique stratified epithelial architecture of human skin along with the antioxidant-response pathways provided vital defensive mechanisms against UV radiation. However, it is noteworthy that skin is a major target for toxic insult by UV radiations that can alter its structure and function. Substantial fraction of information has been added into the existing pool of knowledge related to natural products mediated biological effects in UV exposed skin cells. Accumulating evidence has started to shed light on the potential of these bioactive ingredients as protective natural products in cosmetics against UV photodamage by exerting biological effects mainly through wide ranging intracellular signalling cascades of oxidative stress and modulation of miRNAs. In this review, we have summarized recently emerging scientific evidences addressing underlying mechanisms of UV induced oxidative stress and deregulation of signalling cascades and how natural products can be used tactfully to protect against UV induced harmful effects.

  5. DNA damage and the bystander response in tumor and normal cells exposed to X-rays.

    PubMed

    Subhashree, M; Venkateswarlu, R; Karthik, K; Shangamithra, V; Venkatachalam, P

    2017-09-01

    Monolayer and suspension cultures of tumor (BMG-1, CCRF-CEM), normal (AG1522, HADF, lymphocytes) and ATM-mutant (GM4405) human cells were exposed to X-rays at doses used in radiotherapy (high dose and high dose-rate) or radiological imaging (low dose and low dose-rate). Radiation-induced DNA damage, its persistence, and possible bystander effects were evaluated, based on DNA damage markers (γ-H2AX, p53(ser15)) and cell-cycle-specific cyclins (cyclin B1 and cyclin D1). Dose-dependent DNA damage and a dose-independent bystander response were seen after exposure to high dose and high dose-rate radiation. The level of induced damage (expression of p53(ser15), γ-H2AX) depended on ATM status. However, low dose and dose-rate exposures neither increased expression of marker proteins nor induced a bystander response, except in the CCRF-CEM cells. Bystander effects after high-dose irradiation may contribute to stochastic and deterministic effects. Precautions to protect unexposed regions or to inhibit transmission of DNA damage signaling might reduce radiation risks. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Alterations of protein profile in zebrafish liver cells exposed to methyl parathion: a membrane proteomics approach.

    PubMed

    Huang, Qingyu; Huang, He-Qing

    2012-03-01

    Methyl parathion (MP) is an extensively used organophosphorus pesticide, which has been associated with a wide spectrum of toxic effects on environmental organisms. The aim of this study is to investigate the alterations of membrane protein profiles in zebrafish liver (ZFL) cell line exposed to MP for 24 h using proteomic approaches. Two-dimensional gel electrophoresis revealed a total of 13 protein spots, whose expression levels were significantly altered by MP. These differential proteins were subjected to matrix-assisted laser desorption/ionization tandem time-of-flight mass spectrometry analysis, and nine proteins were identified to be membrane proteins, among which seven were up-regulated, while two were down-regulated. In addition, the mRNA levels corresponding to these differential membrane proteins were further analyzed by quantitative real-time PCR. And the differential expression of arginase-2 was specially validated via Western blotting. Regarding the physiological functions, these proteins are involved in molecular chaperon, cytoskeleton system, cell metabolism, signal transduction, transport and hormone receptor respectively, suggesting the complexity of MP-mediated toxicity to ZFL cell. These data could provide useful insights for better understanding the hepatotoxic mechanisms of MP and develop novel protein biomarkers for effectively monitoring MP contamination level in aquatic environment.

  7. Hemorheological characteristics of red blood cells exposed to surface functionalized graphene quantum dots.

    PubMed

    Kim, Jeongho; Nafiujjaman, Md; Nurunnabi, Md; Lee, Yong-Kyu; Park, Hun-Kuk

    2016-11-01

    Graphene quantum dots (GQDs) are potential candidates for various biomedical applications such as drug delivery, bioimaging, cell labeling, and biosensors. However, toxicological information on their effects on red blood cells (RBCs) and the mechanisms involved remain unexplored. To the best of our knowledge, our study is the first to investigate the toxicity effects of three GQDs with different surface functionalizations on the hemorheological characteristics of human RBCs, including hemolysis, deformability, aggregation, and morphological changes. RBCs were exposed to three different forms of GQDs (non-functionalized, hydroxylated, and carboxylated GQDs) at various concentrations (0, 500, 750, and 1000 μg/mL) and incubation times (0, 1, 2, 3, or 4 h). The rheological characteristics of the RBCs were measured using microfluidic-laser diffractometry and aggregometry. Overall, the hemolysis rate and rheological alterations of the RBCs were insignificant at a concentration less than 500 μg/mL. Carboxylated GQDs were observed to have more substantial hemolytic activity and caused abrupt changes in the deformability and aggregation of the RBCs than the non-functionalized or hydroxylated GQDs at concentrations >750 μg/mL. Our findings indicate that hemorheological assessments could be utilized to estimate the degree of toxicity to cells and to obtain useful information on safety sheets for nanomaterials. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Signaling molecules and cell death in Melissa officinalis plants exposed to ozone.

    PubMed

    Pellegrini, Elisa; Trivellini, Alice; Campanella, Alessandra; Francini, Alessandra; Lorenzini, Giacomo; Nali, Cristina; Vernieri, Paolo

    2013-12-01

    The study focuses on the interaction between reactive oxygen species and hormones that regulate the programmed cell death in plants of Melissa officinalis exposed to ozone. Interaction between hormone and redox signaling pathways has been investigated in ozone-stressed (200 ppb, 5 h) lemon balm to verify if the response resembles the biotic defense reactions. In comparison to controls, plants exhibited foliar injury and the cell death was induced by (1) biphasic production of hydrogen peroxide and superoxide radical; (2) hormonal regulation of ozone-induced lesion formation with a significant production of ethylene, salicylic, jasmonic and abscisic acid; (3) ozone degradation to reactive oxygen species and their detoxification by some enzymatic (such as superoxide dismutase) and non-enzymatic antioxidant systems (such as ascorbic acid, glutathione and carotenoids), that worked in cooperation without providing a defense against free radicals (such as confirmed by the modification of the antioxidant properties of leaf tissue). This integrated view showed that reactive oxygen species interact with hormonal signaling pathway regulating cell death and the sensitivity of lemon balm to ozone.

  9. Noise Removal with Maintained Spatial Resolution in Raman Images of Cells Exposed to Submicron Polystyrene Particles

    PubMed Central

    Ahlinder, Linnea; Wiklund Lindström, Susanne; Lejon, Christian; Geladi, Paul; Österlund, Lars

    2016-01-01

    The biodistribution of 300 nm polystyrene particles in A549 lung epithelial cells has been studied with confocal Raman spectroscopy. This is a label-free method in which particles and cells can be imaged without using dyes or fluorescent labels. The main drawback with Raman imaging is the comparatively low spatial resolution, which is aggravated in heterogeneous systems such as biological samples, which in addition often require long measurement times because of their weak Raman signal. Long measurement times may however induce laser-induced damage. In this study we use a super-resolution algorithm with Tikhonov regularization, intended to improve the image quality without demanding an increased number of collected pixels. Images of cells exposed to polystyrene particles have been acquired with two different step lengths, i.e., the distance between pixels, and compared to each other and to corresponding images treated with the super-resolution algorithm. It is shown that the resolution after application of super-resolution algorithms is not significantly improved compared to the theoretical limit for optical microscopy. However, to reduce noise and artefacts in the hyperspectral Raman images while maintaining the spatial resolution, we show that it is advantageous to use short mapping step lengths and super-resolution algorithms with appropriate regularization. The proposed methodology should be generally applicable for Raman imaging of biological samples and other photo-sensitive samples.

  10. The immunostatus of natural killer cells in people exposed to sulfur mustard.

    PubMed

    Ghotbi, Ladan; Hassan, Zuhair

    2002-06-01

    Sulfur mustard (2,2-dichloroethyl sulfide, SM) has been documented as an alkylating agent. It has been widely used as a chemical weapon during the last two decades. Despite extensive worldwide research, no effective therapy has yet been devised for the treatment of patients exposed to SM. A severe suppression of the immune system still remains as the major cause of opportunistic infections, septicemia and death in such patients. The aim of this study was to determine the possible effect of SM on natural killer (NK) cells in patients suffering from SM injuries. Patients were classified into three groups: mild, moderate and severe. Blood sample obtained from each patient was examined using flowcytometric technique. Results showed that the percentage of NK cells (CD45+/CD56+) is significantly lower in severe patients than that of the control group (P<0.05). It was also observed that the activity of NK cells (CD56+/CD25+) in severe alkylating group is noticeably higher compared with the control group (P<0.1).

  11. Proteomic analysis of cell wall in four pathogenic species of Candida exposed to oxidative stress.

    PubMed

    Ramírez-Quijas, Mayra Denisse; López-Romero, Everardo; Cuéllar-Cruz, Mayra

    2015-10-01

    In order for Candida species to adhere and colonize human host cells they must express cell wall proteins (CWP) and adapt to reactive oxygen species (ROS) generated by phagocytic cells of the human host during the respiratory burst. However, how these pathogens change the expression of CWP in response to oxidative stress (OSR) is not known. Here, fifteen moonlight-like CWP were identified that expressed differentially in four species of Candida after they were exposed to H2O2 or menadione (O2(-)). These proteins included: (i) glycolytic enzymes, such as glyceraldehyde-3-phosphate dehydrogenase (Gapdh), fructose-bisphosphate aldolase (Fba1), phosphoglycerate mutase (Gpm1), phosphoglycerate kinase (Pgk), pyruvate kinase (Pk) and enolase (Eno1); (ii) the heat shock proteins Ssb1 and Ssa2; (iii) OSR proteins such as peroxyredoxin (Tsa1), the stress protein Ddr48 (Ddr48) and glutathione reductase (Glr1); (iv) other metabolic enzymes such as ketol-acid reductoisomerase (Ilv5) and pyruvate decarboxylase (Pdc1); and (v) other proteins such as elongation factor 1-beta (Efb1) and the 14-3-3 protein homolog. RT-PCR revealed that transcription of the genes coding for some of the identified CWP are differentially regulated. To our knowledge this is the first report showing that moonlight-like CWP are the first line of defense of Candida against ROS, and that they are differentially regulated in each of these pathogens. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Cellular processes involved in human epidermal cells exposed to extremely low frequency electric fields.

    PubMed

    Collard, J-F; Hinsenkamp, M

    2015-05-01

    We observed on different tissues and organisms a biological response after exposure to pulsed low frequency and low amplitude electric or electromagnetic fields but the precise mechanism of cell response remains unknown. The aim of this publication is to understand, using bioinformatics, the biological relevance of processes involved in the modification of gene expression. The list of genes analyzed was obtained after microarray protocol realized on cultures of human epidermal explants growing on deepidermized human skin exposed to a pulsed low frequency electric field. The directed acyclic graph on a WebGestalt Gene Ontology module shows six categories under the biological process root: "biological regulation", "cellular process", "cell proliferation", "death", "metabolic process" and "response to stimulus". Enriched derived categories are coherent with the type of in vitro culture, the stimulation protocol or with the previous results showing a decrease of cell proliferation and an increase of differentiation. The Kegg module on WebGestalt has highlighted "cell cycle" and "p53 signaling pathway" as significantly involved. The Kegg website brings out interactions between FoxO, MAPK, JNK, p53, p38, PI3K/Akt, Wnt, mTor or NF-KappaB. Some genes expressed by the stimulation are known to have an exclusive function on these pathways. Analyses performed with Pathway Studio linked cell proliferation, cell differentiation, apoptosis, cell cycle, mitosis, cell death etc. with our microarrays results. Medline citation generated by the software and the fold change variation confirms a diminution of the proliferation, activation of the differentiation and a less well-defined role of apoptosis or wound healing. Wnt and DKK functional classes, DKK1, MACF1, ATF3, MME, TXNRD1, and BMP-2 genes proposed in previous publications after a manual analysis are also highlighted with other genes after Pathway Studio automatic procedure. Finally, an analysis conducted on a list of genes

  13. Lucifer Yellow uptake by CHO cells exposed to magnetic and electric pulses

    PubMed Central

    Towhidi, Leila; Firoozabadi, Seyed Mohammad P; Mozdarani, Hossein; Miklavcic, Damijan

    2012-01-01

    Background The cell membrane acts as a barrier that hinders free entrance of most hydrophilic molecules into the cell. Due to numerous applications in medicine, biology and biotechnology, the introduction of impermeant molecules into biological cells has drawn considerable attention in the past years. One of the most famous methods in this field is electroporation, in which electric pulses with high intensity and short duration are applied to the cells. The aim of our study was to investigate the effect of time-varying magnetic field with different parameters on transmembrane molecular transport. Materials and methods. ‘Moreover, a comparison was made between the uptake results due to magnetic pulse exposure and electroporation mediated uptake.’ at the end of Background part. The Chinese hamster ovary (CHO) cells were exposed to magnetic pulses of 2.2 T peak strength and 250 μs duration delivered by Magstim stimulator and double 70 mm coil. Three different frequencies of 0.25, 1 and 10 Hz pulses with 112, 56 and 28 number of pulses were applied (altogether nine experimental groups) and Lucifer Yellow uptake was measured in each group. Moreover, maximum uptake of Lucifer Yellow obtained by magnetic pulses was compared to the measured uptake due to electroporation with typical parameters of 8 pulses of 100 μs, repetition frequency of 1 Hz and electric field intensities of 200 to 600 V/cm. Results and conclusions. Our results show that time-varying magnetic field exposure increases transmembrane molecular transport and this uptake is greater for lower frequencies and larger number of pulses. Besides, the comparison shows that electroporation is more effective than pulsed magnetic field, but the observed uptake enhancement due to magnetic exposure is still considerable. PMID:23077448

  14. Lucifer Yellow uptake by CHO cells exposed to magnetic and electric pulses.

    PubMed

    Towhidi, Leila; Firoozabadi, Seyed Mohammad P; Mozdarani, Hossein; Miklavcic, Damijan

    2012-06-01

    The cell membrane acts as a barrier that hinders free entrance of most hydrophilic molecules into the cell. Due to numerous applications in medicine, biology and biotechnology, the introduction of impermeant molecules into biological cells has drawn considerable attention in the past years. One of the most famous methods in this field is electroporation, in which electric pulses with high intensity and short duration are applied to the cells. The aim of our study was to investigate the effect of time-varying magnetic field with different parameters on transmembrane molecular transport. 'Moreover, a comparison was made between the uptake results due to magnetic pulse exposure and electroporation mediated uptake.' at the end of Background part. The Chinese hamster ovary (CHO) cells were exposed to magnetic pulses of 2.2 T peak strength and 250 μs duration delivered by Magstim stimulator and double 70 mm coil. Three different frequencies of 0.25, 1 and 10 Hz pulses with 112, 56 and 28 number of pulses were applied (altogether nine experimental groups) and Lucifer Yellow uptake was measured in each group. Moreover, maximum uptake of Lucifer Yellow obtained by magnetic pulses was compared to the measured uptake due to electroporation with typical parameters of 8 pulses of 100 μs, repetition frequency of 1 Hz and electric field intensities of 200 to 600 V/cm. Our results show that time-varying magnetic field exposure increases transmembrane molecular transport and this uptake is greater for lower frequencies and larger number of pulses. Besides, the comparison shows that electroporation is more effective than pulsed magnetic field, but the observed uptake enhancement due to magnetic exposure is still considerable.

  15. Study of damage to red blood cells exposed to different doses of γ-ray irradiation.

    PubMed

    Xu, Deyi; Peng, Mingxi; Zhang, Zhe; Dong, Guofei; Zhang, Yiqin; Yu, Hongwei

    2012-07-01

    The aims of this research were to study alterations in the ultrastructure of red blood cells, the changes in concentrations of plasma electrolytes and the killing effect of lymphocytes in samples of blood exposed to different doses of γ-ray irradiation. Blood samples were treated with different doses of γ-ray irradiation and then preserved for different periods. Specimens were prepared for standard electron microscopy and transmission electron microscopy. At the same time, changes in the concentrations of Na(+), K(+) and Cl(-) and pH values in the plasma as well as Fas and FasL expression of lymphocytes before and after irradiation were determined. The proportions of reversibly and irreversibly transformed cells, for example, echinocytes, sphero-echinocytes, and degenerated forms, increased with increasing doses of irradiation and storage period, while the number of discocyte shaped red blood cells decreased. The change in K(+) concentration was greater than that of Na+ or Cl(-) after irradiation and was dosage-dependent. Plasma pH was influenced by different doses of radiation and storage time. After exposure to (137)Cs γ-irradiation, the expression of both Fas and FasL in lymphocytes differed significantly from that in the control group: the expression was positively correlated with irradiation dose (r=0.95, 0.96), but no significant difference in the Fas/FasL ratio was observed (P>0.05). We conclude that the ultrastructure of red blood cells is not changed obviously by irradiation with some doses of γ-rays and various periods of storage. However, irradiation does have some dose-dependent and time-dependent adverse effects on the erythrocytes.

  16. Ergothioneine products derived by superoxide oxidation in endothelial cells exposed to high-glucose.

    PubMed

    Servillo, Luigi; D'Onofrio, Nunzia; Casale, Rosario; Cautela, Domenico; Giovane, Alfonso; Castaldo, Domenico; Balestrieri, Maria Luisa

    2017-03-12

    Ergothioneine (Egt), 2-mercapto-L-histidine betaine (ESH), is a dietary component acting as antioxidant and cytoprotectant. In vitro studies demonstrated that Egt, a powerful scavenger of hydroxyl radicals, superoxide anion, hypochlorous acid and peroxynitrite, protects vascular function against oxidative damages, thus preventing endothelial dysfunction. In order to delve the peculiar oxidative behavior of Egt, firstly identified in cell free-systems, experiments were designed to identify the Egt oxidation products when endothelial cells (EC) benefit of its protection against high-glucose (hGluc). HPLC-ESI-MS/MS analyses revealed a decrease in the intracellular GSH levels and an increase in the ophthalmic acid (OPH) levels during hGluc treatment. Interestingly, in the presence of Egt, the decrease of the GSH levels was lower than in cells treated with hGluc alone, and this effect was paralleled by lower OPH levels. Egt was also effective in reducing the cytotoxicity of H2O2 and paraquat (PQT), an inducer of superoxide anion production, showing a similar time-dependent pattern of GSH and OPH levels, although with peaks occurring at different times. Importantly, Egt oxidation generated not only hercynine (EH) but also the sulfonic acid derivative (ESO3H) whose amounts were dependent on the oxidative stress employed. Furthermore, cell-free experiments confirmed the formation of both EH and ESO3H when Egt was reacted with superoxide anion. In summary, these data, by identifying the EH and ESO3H formation in EC exposed to hGluc, highlight the cellular antioxidant properties of Egt, whose peculiar redox behavior makes it an attractive candidate for the prevention of oxidative stress-associated endothelial dysfunction during hyperglycemia.

  17. Antioxidant status and selected biochemical parameters of porcine ovarian granulosa cells exposed to lead in vitro.

    PubMed

    Capcarová, Marcela; Kolesárová, Adriana; Lukác, Norbert; Sirotkin, Alexander; Roychoudhury, Shubhadeep

    2009-12-01

    The objective of this study was to determine the activity of superoxide dismutase (SOD), total antioxidant status (TAS) and release of calcium, phosphorus, magnesium, sodium, potassium, total lipids, totals proteins, glucose, cholesterol and triglycerides by porcine ovarian granulosa cells cultured in vitro after lead acetate administration. The parameters were analyzed using semi-automated clinical chemistry analyzer Microlab 300, microprocessor-controlled analyzer EasyLite and spectrophotometer Genesys 10. Cells were cultured with lead acetate trihydrate [Pb(CH(3)COO)(2).3H(2)O] as follows: group Max (5 mg Pb(CH(3)COO)(2).3H(2)O/10 mL), group A (2.5 mg/10 mL), group B (0.83 mg/10 mL), group C (0.625 mg/10 mL), group D (0.455 mg/10 mL) and the control group without lead exposure for 18 hrs. The highest TAS was estimated in the control group without lead treatment in comparison with other groups (MAX, A, B, C, D). Statistical analyses showed significantly lower value (P < 0.05) in group B. The activity of SOD was the lowest in the control group in comparison to those exposed to in vitro lead culture. A significant decrease (P < 0.05) of calcium content in group MAX in comparison with control group was determined. Release of phosphorus by ovarian granulosa cells was significantly lower (P < 0.05; 0.01; 0.001) in all the treated groups in comparison with control group. Lead was found to stimulate the release of magnesium and potassium by granulosa cells, but the increase remained statistically insignificant. The highest concentration of glucose was noted in control group, but the differences were not significant either. No significant differences (P > 0.05) were detected in concentration of other studied parameters among observed groups, too.

  18. Genetic polymorphisms and surface expression of CTLA-4 and PD-1 on T cells of silica-exposed workers.

    PubMed

    Rocha, Michelle C; Santos, Leonilda M B; Bagatin, Ericson; Cohen Tervaert, Jan W; Damoiseaux, Jan G M C; Lido, Alessandro V; Longhini, Ana L; Torello, Cristiane O; Queiroz, Mary L S

    2012-11-01

    Exposure to silica dust has been examined as a possible risk factor for autoimmune diseases, including scleroderma, rheumatoid arthritis and systemic lupus erythematosus. Since CTLA-4 [CD152] and PD-1 [CD279] are important for the maintenance of peripheral tolerance by regulating T cell responsiveness, we evaluated the expression of these molecules on the surface of CD4 and CD8 T cells, as well as single nucleotide polymorphisms (SNP) in CTLA-4 and PDCD1 genes, of 70 silica-exposed workers and 30 non-exposed, age-, ethnically- and sex-matched controls. Expression of CTLA-4 was significantly (P<0.05) reduced in CD4 T cells of exposed individuals [median=0.1% and interquartile range, IQR 0.0-0.1% (exposed), median=0.20%, IQR 0.0-0.4% (control)]. Also the expression of PD-1 was significantly (P<0.0001) reduced in both CD4 [median=0.9%, IQR 0.4-2.3% (exposed), median=5.7%, IQR 1.4-13.3% (control)] and CD8 T cells [median=0.9%, IQR 0.3-1.9% (exposed), median=5.0%, IQR 3.4-8.9% (control)]. The study of polymorphisms demonstrated a lower frequency of the A allele in the analysis of the PD1.3 SNP in the exposed group, which might be associated with the lower expression of PD-1 on the surface of CD4 T cells. Our findings provide evidence for the association of silica exposure and the maintenance of self-tolerance, i.e., the susceptibility to autoimmune disorders.

  19. Profiling transcriptomes of human SH-SY5Y neuroblastoma cells exposed to maleic acid

    PubMed Central

    Wang, Chia-Chi; Lin, Yin-Chi; Cheng, Yin-Hua

    2017-01-01

    Background Maleic acid is a multi-functional chemical widely used in the field of industrial chemistry for producing food additives and food contact materials. As maleic acid may contaminate food by the release from food packages or intentional addition, it raises the concern about the effects of excessive dietary exposure to maleic acid on human health. However, the influence of maleic acid on human health has not been thoroughly studied. In silico toxicogenomics approaches have found the association between maleic acid and nervous system disease in human. The aim of this study is to experimentally explore the effects of maleic acid on human neuronal cells. Methods A microarray-based transcriptome profiling was performed to offer a better understanding of the effects of maleic acid on human health. Gene expression profiles of human neuroblastoma SH-SY5Y cells exposed to three concentrations of maleic acid (10, 50, and 100 μM) for 24 h were analyzed. Genes which were differentially expressed in dose-dependent manners were identified and further analyzed with an enrichment analysis. The expression profile of selected genes related to the inferred functional changes was validated using quantitative polymerase chain reaction (qPCR). Specific fluorescence probes were applied to observe the inferred functional changes in maleic acid-treated neuronal cells. Results A total of 316 differentially expressed genes (141 upregulated and 175 downregulated) were identified in response to the treatment of maleic acid. The enrichment analysis showed that DNA binding and metal ion binding were the significant molecular functions (MFs) of the neuronal cells affected by maleic acid. Maleic acid exposure decreased the expression of genes associated with calcium and thiol levels of the cells in a dose-dependent manner. The levels of intracellular calcium and thiol levels were also affected by maleic acid dose-dependent. Discussion The exposure to maleic acid is found to decrease the

  20. Novel leukocyte agonists are released by endothelial cells exposed to peroxide.

    PubMed

    Patel, K D; Zimmerman, G A; Prescott, S M; McIntyre, T M

    1992-07-25

    Reactive oxygen species do not activate isolated neutrophils, yet in vivo, such oxidants promote their adhesion to, and subsequent migration through, the vascular wall. We show human endothelial cells exposed to t-butylhydroperoxide shed large, sealed membrane vesicles that contained potent neutrophil agonists. This activity migrated on TLC like platelet-activating factor (PAF). Since neutrophils have a receptor for this phospholipid, which recognizes its unique characteristics including the short sn-2 acetyl residue, we examined the effect of PAF receptor antagonists and PAF acetylhydrolase on this activity. Structurally unrelated PAF receptor antagonists blocked neutrophil stimulation by vesicular phospholipids, and digestion with PAF acetylhydrolase, which is specific for short sn-2 residues, destroyed this activity. However, metabolic labeling, inhibition of synthesis, phospholipase A1 digestion, and high performance liquid chromatographic studies demonstrated that the vesicles did not contain PAF. Instead, the bioactivity migrated on high performance liquid chromatography like the phospholipids generated by oxidative fragmentation of synthetic arachidonoyl phosphatidylcholine that we have shown previously (Smiley, P. L., Stremler, K. E., Prescott, S. M., Zimmerman, G. A., and McIntyre, T. M. (1991) J. Biol. Chem. 266, 11104-11110) to stimulate neutrophils through their receptor for PAF. Thus, peroxide treatment of endothelial cells fragments cellular phosphatidylcholines, forming novel PAF-like phospholipids, and induces the shedding of membrane vesicles that contain these bioactive phospholipids.

  1. Multiwalled carbon nanotubes enter broccoli cells enhancing growth and water uptake of plants exposed to salinity.

    PubMed

    Martínez-Ballesta, M Carmen; Zapata, Lavinia; Chalbi, Najla; Carvajal, Micaela

    2016-06-08

    Carbon nanotubes have been shown to improve the germination and growth of some plant species, extending the applicability of the emerging nano-biotechnology field to crop science. In this work, exploitation of commercial multiwalled carbon nanotubes (MWCNTs) in control and 100 mM NaCl-treated broccoli was performed. Transmission electron microscopy demonstrated that MWCNTs can enter the cells in adult plants with higher accumulation under salt stress. Positive effect of MWCNTs on growth in NaCl-treated plants was consequence of increased water uptake, promoted by more-favourable energetic forces driving this process, and enhanced net assimilation of CO2. MWCNTs induced changes in the lipid composition, rigidity and permeability of the root plasma membranes relative to salt-stressed plants. Also, enhanced aquaporin transduction occurred, which improved water uptake and transport, alleviating the negative effects of salt stress. Our work provides new evidences about the effect of MWCNTs on plasma membrane properties of the plant cell. The positive response to MWCNTs in broccoli plants opens novel perspectives for their technological uses in new agricultural practices, especially when 1plants are exposed to saline environments.

  2. DNA damage in blood cells exposed to low-level lasers.

    PubMed

    Sergio, Luiz Philippe da Silva; Silva, Ana Paula Almeida da; Amorim, Philipi Freitas; Campos, Vera Maria Araújo; Magalhães, Luis Alexandre Gonçalves; de Paoli, Flavia; de Souza da Fonseca, Adenilson

    2015-04-01

    In regenerative medicine, there are increasing applications of low-level lasers in therapeutic protocols for treatment of diseases in soft and in bone tissues. However, there are doubts about effects on DNA, and an adequate dosimetry could improve the safety of clinical applications of these lasers. This work aimed to evaluate DNA damage in peripheral blood cells of Wistar rats induced by low-level red and infrared lasers at different fluences, powers, and emission modes according to therapeutic protocols. Peripheral blood samples were exposed to lasers and DNA damage was accessed by comet assay. In other experiments, DNA damage was accessed in blood cells by modified comet assay using formamidopyrimidine DNA glycosylase (Fpg) and endonuclease III enzymes. Data show that exposure to low-level red and infrared lasers induce DNA damage depending on fluence, power and emission mode, which are targeted by Fpg and endonuclease III. Oxidative DNA damage should be considered for therapeutic efficacy and patient safety in clinical applications based on low-level red and infrared lasers. © 2015 Wiley Periodicals, Inc.

  3. Human Invariant Natural Killer T Cells Respond to Antigen-Presenting Cells Exposed to Lipids from Olea europaea Pollen.

    PubMed

    Abos Gracia, Beatriz; López Relaño, Juan; Revilla, Ana; Castro, Lourdes; Villalba, Mayte; Martín Adrados, Beatriz; Regueiro, Jose Ramon; Fernández-Malavé, Edgar; Martínez Naves, Eduardo; Gómez Del Moral, Manuel

    2017-01-01

    Allergic sensitization might be influenced by the lipids present in allergens, which can be recognized by natural killer T (NKT) cells on antigen-presenting cells (APCs). The aim of this study was to analyze the effect of olive pollen lipids in human APCs, including monocytes as well as monocyte-derived macrophages (Mϕ) and dendritic cells (DCs). Lipids were extracted from olive (Olea europaea) pollen grains. Invariant (i)NKT cells, monocytes, Mϕ, and DCs were obtained from buffy coats of healthy blood donors, and their cell phenotype was determined by flow cytometry. iNKT cytotoxicity was measured using a lactate dehydrogenase assay. Gene expression of CD1A and CD1D was performed by RT-PCR, and the production of IL-6, IL-10, IL-12, and TNF-α cytokines by monocytes, Mϕ, and DCs was measured by ELISA. Our results showed that monocytes and monocyte-derived Mϕ treated with olive pollen lipids strongly activate iNKT cells. We observed several phenotypic modifications in the APCs upon exposure to pollen-derived lipids. Both Mϕ and monocytes treated with olive pollen lipids showed an increase in CD1D gene expression, whereas upregulation of cell surface CD1d protein occurred only in Mϕ. Furthermore, DCs differentiated in the presence of human serum enhance their surface CD1d expression when exposed to olive pollen lipids. Finally, olive pollen lipids were able to stimulate the production of IL-6 but downregulated the production of lipopolysaccharide- induced IL-10 by Mϕ. Olive pollen lipids alter the phenotype of monocytes, Mϕ, and DCs, resulting in the activation of NKT cells, which have the potential to influence allergic immune responses. © 2017 S. Karger AG, Basel.

  4. Aortic smooth muscle cell alterations in mice systemically exposed to arsenic.

    PubMed

    Chen, Shih-Chieh; Huang, Shin-Yin; Lin, Wen-Ting; Yang, Rei-Cheng; Yu, Hsin-Su

    2016-05-01

    Previous epidemiological studies showed that chronic arsenic exposure is related to increased cardiovascular disease incidence. The detailed biochemical mechanisms by which arsenic exerts its effects remain unknown. Vascular disease progression is characterized by smooth muscle cell (SMC) phenotypic switching, vessel wall reorganization, and platelet-derived growth factor (PDGF) production. The objective of this study was to examine early biochemical and structural changes in the aortas of ICR mice systemically exposed to arsenic. Animals were fed sodium arsenite (20 mg/kg) via gavage 5 days/week or Milli-Q water only (control) for 8 weeks. Aortic proteins were subjected to two-dimensional (2-D) differential gel electrophoresis and proteomic studies. Two 2-D gel protein spots were identified as the same protein, smooth muscle (SM)22α, using proteomics. SM22α and Rho kinase 2 gene and protein expression were significantly decreased in the aortic tissue of arsenic-exposed mice compared with that of control mice. No atherosclerotic lesion formation or tissue injury was detected in the aortic wall of either the arsenic-fed or the control group. However, the percent (%) SMC area of the aortic wall was significantly decreased in arsenic-fed mice compared with that in control mice. Additionally, the expression levels of PDGF-BB and early growth response-1 (Egr-1) were significantly higher in the arsenic group than that in the control group. These findings reveal biochemical alterations of SM22α, PDGF, and Egr-1 in conjunction with decreased SMC area in the aortic wall of arsenic-fed mice. Arsenic may initiate aortic SMC alterations that subsequently lead to vascular dysfunction.

  5. Threshold radiant exposure for cell death in the endothelium of porcine cornea exposed to ultrashort laser pulses

    NASA Astrophysics Data System (ADS)

    Hussain, S. A.; Kowalczuk, L.; Crotti, C.; Alahyane, F.; Plamann, K.

    2013-06-01

    We have determined the threshold radiant exposure for cell death in the endothelium of porcine cornea exposed to ultrashort laser pulses in the context of keratoplasty and the preparation of endothelial grafts. In this study, by progressively increasing the radiant threshold towards the higher values we have observed a decrease of living corneal endothelial cells. Further study will address the effect of dose and possible mechanism behind cell death.

  6. Survival of mammalian cells exposed to ultrahigh dose rates from a laser-produced plasma x-ray source.

    PubMed

    Tillman, C; Grafström, G; Jonsson, A C; Jönsson, B A; Mercer, I; Mattsson, S; Strand, S E; Svanberg, S

    1999-12-01

    To determine whether intense laser-produced x rays have an increased radiation hazard. Mammalian cells were exposed to x rays from a laser-produced plasma that produced ultrahigh peak absorbed dose rates, up to a factor of 10(10) higher than those produced by conventional x rays used in imaging. The cell survival was studied as a function of the absorbed dose. The survival of mammalian cells exposed to high peak absorbed dose rates with laser-produced x rays was compared with the survival of cells exposed to standard absorbed dose rates with conventional x-ray sources. Comparative survival studies were performed by using a conventional x-ray tube and a cobalt 60 source. The absorbed doses in the irradiation field were measured with thermoluminescent dosimeters. Cell survival following irradiation by filtered, laser-produced x rays with a high dose rate was not markedly different from the survival following irradiation by conventional sources. There was, however, a notable difference between the survival after exposure to filtered, laser-produced x rays and the survival after exposure to unfiltered laser-produced x rays. Exposure to filtered, laser-produced x rays with a high dose rate does not lead to increased harm to mammalian cells exposed in vitro compared with the harm from exposure to x rays from conventional sources, which indicates that the use of high-power laser facilities for medical imaging is justified.

  7. Effects of exposing chicken eggs to a cell phone in "call" position over the entire incubation period.

    PubMed

    Batellier, F; Couty, I; Picard, D; Brillard, J P

    2008-04-01

    The aim of the present study was to assess the effects of exposing fertile chicken eggs to a cell phone repeatedly calling a ten-digit number at 3-min intervals over the entire period of incubation. A pre-experiment was performed first to adjust incubation conditions in an experimental chamber devoid of metallic content and without automatic turning until the overall performance of hatchability was reproducible in the absence of the cell phone. The experimental period consisted of a series of 4 incubations referred to as "replicates". For each replicate, one batch of 60 eggs was exposed to the immediate environment (cell phone in the "call" position (exposed group), while another batch of 60 eggs, 1.5m away from the exposed group and also in the incubation chamber, was exposed to a similar cell phone in the "off" position (sham group). For each replicate, 2 other groups each of 60 eggs were also incubated, one in a standard mini-incubator ("Control I" group) and the second in a standard medium size incubator ("Control II" group). Temperature, relative humidity and electromagnetic fields in the experimental chamber were permanently monitored over the entire experiment. A significantly higher percentage of embryo mortality was observed in the "exposed" compared to the "sham" group in 2 of the 4 replicates (p< .05). In comparison with control groups, additional embryo mortality in the exposed group occurred mainly between Days 9 and 12 of incubation but a causal relationship between the intensity of the electric field and embryo mortality could not be established.

  8. Proteomic responses of human intestinal Caco-2 cells exposed to silver nanoparticles and ionic silver.

    PubMed

    Oberemm, Axel; Hansen, Ulf; Böhmert, Linda; Meckert, Christine; Braeuning, Albert; Thünemann, Andreas F; Lampen, Alfonso

    2016-03-01

    Even although quite a number of studies have been performed so far to demonstrate nanoparticle-specific effects of substances in living systems, clear evidence of these effects is still under debate. The present study was designed as a comparative proteomic analysis of human intestinal cells exposed to a commercial silver nanoparticle reference material and ions from AgNO3. A two-dimensional gel electrophoresis/MALDI mass spectrometry (MS)-based proteomic analysis was conducted after 24-h incubation of differentiated Caco-2 cells with non-cytotoxic and low cytotoxic silver concentrations (2.5 and 25 µg ml(-1) nanosilver, 0.5 and 5 µg ml(-1) AgNO3). Out of an overall number of 316 protein spots differentially expressed at a fold change of ≥ 1.4 or ≤ -1.4 in all treatments, 169 proteins could be identified. In total, 231 spots were specifically deregulated in particle-treated groups compared with 41 spots, which were limited to AgNO3-treatments. Forty-four spots (14 %) were commonly deregulated by both types of treatment. A considerable fraction of the proteins differentially expressed after treatment with nanoparticles is related to protein folding, synthesis or modification of proteins as well as cellular assembly and organization. Overlays of networks obtained for particulate and ionic treatments showed matches, indicating common mechanisms of combined particle and ionic silver exposure and exclusive ionic silver treatment. However, proteomic responses of Caco-2 cells treated with higher concentrations of silver species also showed some differences, for example regarding proteins related to fatty acid and energy metabolism, suggesting an induction of also some different molecular mechanisms for particle exposure and ionic treatment.

  9. Oxidative stress response in neural stem cells exposed to different superparamagnetic iron oxide nanoparticles

    PubMed Central

    Pongrac, Igor M; Pavičić, Ivan; Milić, Mirta; Brkić Ahmed, Lada; Babič, Michal; Horák, Daniel; Vinković Vrček, Ivana; Gajović, Srećko

    2016-01-01

    Biocompatibility, safety, and risk assessments of superparamagnetic iron oxide nanoparticles (SPIONs) are of the highest priority in researching their application in biomedicine. One improvement in the biological properties of SPIONs may be achieved by different functionalization and surface modifications. This study aims to investigate how a different surface functionalization of SPIONs – uncoated, coated with d-mannose, or coated with poly-l-lysine – affects biocompatibility. We sought to investigate murine neural stem cells (NSCs) as important model system for regenerative medicine. To reveal the possible mechanism of toxicity of SPIONs on NSCs, levels of reactive oxygen species, intracellular glutathione, mitochondrial membrane potential, cell-membrane potential, DNA damage, and activities of SOD and GPx were examined. Even in cases where reactive oxygen species levels were significantly lowered in NSCs exposed to SPIONs, we found depleted intracellular glutathione levels, altered activities of SOD and GPx, hyperpolarization of the mitochondrial membrane, dissipated cell-membrane potential, and increased DNA damage, irrespective of the surface coating applied for SPION stabilization. Although surface coating should prevent the toxic effects of SPIONs, our results showed that all of the tested SPION types affected the NSCs similarly, indicating that mitochondrial homeostasis is their major cellular target. Despite the claimed biomedical benefits of SPIONs, the refined determination of their effects on various cellular functions presented in this work highlights the need for further safety evaluations. This investigation helps to fill the knowledge gaps on the criteria that should be considered in evaluating the biocompatibility and safety of novel nanoparticles. PMID:27217748

  10. The influence of medium conductivity on cells exposed to nsPEF

    NASA Astrophysics Data System (ADS)

    Moen, Erick K.; Ibey, Bennett L.; Roth, Caleb C.; Barnes, Ronald A.; Beier, Hope T.; Armani, Andrea M.

    2017-02-01

    Nanosecond pulsed electric fields (nsPEF) have proven useful for transporting cargo across cell membranes and selectively activating cellular pathways. The chemistry and biophysics governing this cellular response, however, are complex and not well understood. Recent studies have shown that the conductivity of the solution cells are exposed in could play a significant role in plasma membrane permeabilization and, thus, the overall cellular response. Unfortunately, the means of detecting this membrane perturbation has traditionally been limited to analyzing one possible consequence of the exposure - diffusion of molecules across the membrane. This method has led to contradictory results with respect to the relationship between permeabilization and conductivity. Diffusion experiments also suffer from "saturation conditions" making multi-pulse experiments difficult. As a result, this method has been identified as a key stumbling block to understanding the effects of nsPEF exposure. To overcome these limitations, we recently developed a nonlinear optical imaging technique based on second harmonic generation (SHG) that allows us to identify nanoporation in live cells during the pulse in a wide array of conditions. As a result, we are able to explore and fully test whether lower conductivity extracellular solutions could induce more efficient nanoporation. This hypothesis is based on membrane charging and the relative difference between the extracellular solution and the cytoplasm. The experiments also allow us to test the noise floor of our methodology against the effects of ion leakage. The results emphasize that the electric field, not ionic phenomenon, are the driving force behind nsPEF-induced membrane nanoporation.

  11. Distribution of Chromosome Breakpoints in Human Epithelial Cells Exposed to Low- and High-LET Radiations

    NASA Technical Reports Server (NTRS)

    Hada, Megumi; Cucinotta, Francis; Wu, Honglu

    2009-01-01

    The advantage of the multicolor banding in situ hybridization (mBAND) technique is not only its ability to identify simultaneously both inter- and intrachromosome exchanges, but also the ability to measure the breakpoint location along the length of the chromosome in a precision that is unmatched with other traditional banding techniques. Breakpoints on specific regions of a chromosome have been known to associate with specific cancers. The breakpoint distribution in cells after low- and high-LET radiation exposures will also provide the data for biophysical modeling of the chromatin structure, as well as the data for the modeling the formation of radiation-induced chromosome aberrations. In a series of experiments, we studied low- and high-LET radiation-induced chromosome aberrations using the mBAND technique with chromosome 3 painted in 23 different colored bands. Human epithelial cells (CH1 84B5F5/M10) were exposed in vitro to Cs- 137 rays at both low and high dose rates, secondary neutrons with a broad energy spectrum at a low dose rate and 600 MeV/u Fe ions at a high dose rate. The data of both inter- and intrachromosome aberrations involving the painted chromosome have been reported previously. Here we present data of the location of the chromosome breaks along the length of chromosome 3 in the cells after exposures to each of the four radiation scenarios. In comparison to the expected breakpoint distribution based on the length of the bands, the observed distribution appeared to be non-random for both the low- and high-LET radiations. In particular, hot spots towards both ends of the chromosome were found after low-LET irradiations of either low or high dose rates. For both high-LET radiation types (Fe ions and neutrons), the breakpoint distributions were similar, and were much smoother than that for low-LET radiation. The dependence of the breakpoint distribution on the radiation quality requires further investigations.

  12. Distribution of Chromosome Breakpoints in Human Epithelial Cells Exposed to Low- and High-LET Radiations

    NASA Technical Reports Server (NTRS)

    Hada, Megumi; Cucinotta, Francis; Wu, Honglu

    2009-01-01

    The advantage of the multicolor banding in situ hybridization (mBAND) technique is not only its ability to identify simultaneously both inter- and intrachromosome exchanges, but also the ability to measure the breakpoint location along the length of the chromosome in a precision that is unmatched with other traditional banding techniques. Breakpoints on specific regions of a chromosome have been known to associate with specific cancers. The breakpoint distribution in cells after low- and high-LET radiation exposures will also provide the data for biophysical modeling of the chromatin structure, as well as the data for the modeling the formation of radiation-induced chromosome aberrations. In a series of experiments, we studied low- and high-LET radiation-induced chromosome aberrations using the mBAND technique with chromosome 3 painted in 23 different colored bands. Human epithelial cells (CH1 84B5F5/M10) were exposed in vitro to Cs- 137 rays at both low and high dose rates, secondary neutrons with a broad energy spectrum at a low dose rate and 600 MeV/u Fe ions at a high dose rate. The data of both inter- and intrachromosome aberrations involving the painted chromosome have been reported previously. Here we present data of the location of the chromosome breaks along the length of chromosome 3 in the cells after exposures to each of the four radiation scenarios. In comparison to the expected breakpoint distribution based on the length of the bands, the observed distribution appeared to be non-random for both the low- and high-LET radiations. In particular, hot spots towards both ends of the chromosome were found after low-LET irradiations of either low or high dose rates. For both high-LET radiation types (Fe ions and neutrons), the breakpoint distributions were similar, and were much smoother than that for low-LET radiation. The dependence of the breakpoint distribution on the radiation quality requires further investigations.

  13. Proliferation assay of mouse embryonic stem (ES) cells exposed to atmospheric-pressure plasmas at room temperature

    NASA Astrophysics Data System (ADS)

    Miura, Taichi; Ando, Ayumi; Hirano, Kazumi; Ogura, Chika; Kanazawa, Tatsuya; Ikeguchi, Masamichi; Seki, Atsushi; Nishihara, Shoko; Hamaguchi, Satoshi

    2014-11-01

    Proliferation assays of mouse embryonic stem (ES) cells have been performed with cell culture media exposed to atmospheric-pressure plasmas (APPs), which generate reactive species in the media at room temperature. It is found that serum in cell culture media functions as a scavenger of highly reactive species and tends to protect cells in the media against cellular damage. On the other hand, if serum is not present in a cell culture medium when it is exposed to APP, the medium becomes cytotoxic and cannot be detoxified by serum added afterwards. Plasma-induced cytotoxic media hinder proliferation of mouse ES cells and may even cause cell death. It is also shown by nuclear magnetic resonance spectroscopy that organic compounds in cell culture media are in general not significantly modified by plasma exposure. These results indicate that if there is no serum in media when they are exposed to APPs, highly reactive species (such as OH radicals) generated in the media by the APP exposure are immediately converted to less reactive species (such as H2O2), which can no longer readily react with serum that is added to the medium after plasma exposure. This study has clearly shown that it is these less reactive species, rather than highly reactive species, that make the medium cytotoxic to mouse ES cells.

  14. Beclin-1 Expression in Normal Bladder and in Cd+2 and As+3 Exposed and Transformed Human Urothelial Cells (UROtsa)

    PubMed Central

    Larson, Jennifer L.; Somji, Seema; Zhou, Xu Dong; Sens, Mary Ann; Garrett, Scott H.; Sens, Donald A.; Dunlevy, Jane R.

    2010-01-01

    The expression of beclin-1 in normal human bladder and in Cd+2 and As+3 exposed and transformed urothelial cells (UROtsa) was examined in this study. It was shown using a combination of real time PCR, western analysis and immunohistochemistry that beclin-1 was expressed in the urothelial cells of the normal bladder. It was also demonstrated that the parental UROtsa cell line expressed beclin-1 mRNA and protein at levels similar to that of the in situ urothelium. The level of beclin-1 expression underwent only modest alterations when the UROtsa cells were malignantly transformed by Cd+2 or As+3 or when the parental cells were exposed acutely to Cd+2 or As+3. While there were instances of significant alterations at individual time points and within cell line-to-cell line comparisons there was no evidence of a dose response relationship or correlations to the phenotypic properties of the cell lines. Similar results were obtained for the expression of the Atg-5, Atg-7, Atg-12 and LC3B autophagy-related proteins. The findings provide initial evidence for beclin-1 expression in normal bladder and that large alterations in the expression of beclin-1 and associated proteins do not occur when human urothelial cells are malignantly transformed with, or exposed to, either Cd+2 or As+3. PMID:20206246

  15. Interaction with cellular CD4 exposes HIV-1 envelope epitopes targeted by antibody-dependent cell-mediated cytotoxicity.

    PubMed

    Veillette, Maxime; Désormeaux, Anik; Medjahed, Halima; Gharsallah, Nour-Elhouda; Coutu, Mathieu; Baalwa, Joshua; Guan, Yongjun; Lewis, George; Ferrari, Guido; Hahn, Beatrice H; Haynes, Barton F; Robinson, James E; Kaufmann, Daniel E; Bonsignori, Mattia; Sodroski, Joseph; Finzi, Andrés

    2014-03-01

    Anti-HIV-1 envelope glycoprotein (Env) antibodies without broadly neutralizing activity correlated with protection in the RV144 clinical trial, stimulating interest in other protective mechanisms involving antibodies, such as antibody-dependent cell-mediated cytotoxicity (ADCC). Env epitopes targeted by many antibodies effective at mediating ADCC are poorly exposed on the unliganded Env trimer. Here we investigated the mechanism of exposure of ADCC epitopes on Env and showed that binding of Env and CD4 within the same HIV-1-infected cell effectively exposes these epitopes. Env capacity to transit to the CD4-bound conformation is required for ADCC epitope exposure. Importantly, cell surface CD4 downregulation by Nef and Vpu accessory proteins and Vpu-mediated BST-2 antagonism modulate exposure of ADCC-mediating epitopes and reduce the susceptibility of infected cells to this effector function in vitro. Significantly, Env conformational changes induced by cell surface CD4 are conserved among Env from HIV-1 and HIV-2/SIVmac lineages. Altogether, our observations describe a highly conserved mechanism required to expose ADCC epitopes that might help explain the evolutionary advantage of downregulation of cell surface CD4 by the HIV-1 Vpu and Nef proteins. HIV-1 envelope epitopes targeted by many antibodies effective at mediating antibody-dependent cell-mediated cytotoxicity (ADCC) are poorly exposed on the unliganded envelope trimer. Here we investigated the mechanism of exposure of these epitopes and found that envelope interaction with the HIV-1 CD4 receptor is required to expose some of these epitopes. Moreover, our results suggest that HIV-1 CD4 downregulation might help avoid the killing of HIV-1-infected cells by this immune mechanism.

  16. Osteoblastic differentiation and stress response of human mesenchymal stem cells exposed to alternating current electric fields.

    PubMed

    Hronik-Tupaj, Marie; Rice, William L; Cronin-Golomb, Mark; Kaplan, David L; Georgakoudi, Irene

    2011-01-26

    Electric fields are integral to many biological events, from maintaining cellular homeostasis to embryonic development to healing. The application of electric fields offers substantial therapeutic potential, while optimal dosing regimens and the underlying mechanisms responsible for the positive clinical impact are poorly understood. The purpose of this study was to track the differentiation profile and stress response of human bone marrow derived mesenchymal stem cells (hMSCs) undergoing osteogenic differentiation during exposure to a 20 mV/cm, 60 kHz electric field. Morphological and biochemical changes were imaged using endogenous two-photon excited fluorescence (TPEF) and quantitatively assessed through eccentricity calculations and extraction of the redox ratio from NADH, FAD and lipofuscin contributions. Real time reverse transcriptase-polymerase chain reactions (RT-PCR) were used to track osteogenic differentiation markers, namely alkaline phosphatase (ALP) and collagen type 1 (col1), and stress response markers, such as heat shock protein 27 (hsp27) and heat shock protein 70 (hsp70). Comparisons of collagen deposition between the stimulated hMSCs and controls were examined through second harmonic generation (SHG) imaging. Quantitative differences in cell morphology, as described through an eccentricity ratio, were found on days 2 and days 5 (p < 0.05) in samples exposed to the electric field. A delayed but two fold increase in ALP and col1 transcript was detected by week 2 (p < 0.05) in differentiating hMSCs exposed to an electric field in comparison to the nonstimulated controls. Upregulation in stress marker, hsp27, and type 1 collagen deposition were correlated with this response. Increases in NADH, FAD, and lipofuscin were traced in the stimulation group during the first week of field exposure with differences statistically significant on day 10 (p < 0.05). Changes in hsp27 expression correlate well with changes in lipofuscin detected in the stimulation

  17. Osteoblastic differentiation and stress response of human mesenchymal stem cells exposed to alternating current electric fields

    PubMed Central

    2011-01-01

    Background Electric fields are integral to many biological events, from maintaining cellular homeostasis to embryonic development to healing. The application of electric fields offers substantial therapeutic potential, while optimal dosing regimens and the underlying mechanisms responsible for the positive clinical impact are poorly understood. Methods The purpose of this study was to track the differentiation profile and stress response of human bone marrow derived mesenchymal stem cells (hMSCs) undergoing osteogenic differentiation during exposure to a 20 mV/cm, 60 kHz electric field. Morphological and biochemical changes were imaged using endogenous two-photon excited fluorescence (TPEF) and quantitatively assessed through eccentricity calculations and extraction of the redox ratio from NADH, FAD and lipofuscin contributions. Real time reverse transcriptase-polymerase chain reactions (RT-PCR) were used to track osteogenic differentiation markers, namely alkaline phosphatase (ALP) and collagen type 1 (col1), and stress response markers, such as heat shock protein 27 (hsp27) and heat shock protein 70 (hsp70). Comparisons of collagen deposition between the stimulated hMSCs and controls were examined through second harmonic generation (SHG) imaging. Results Quantitative differences in cell morphology, as described through an eccentricity ratio, were found on days 2 and days 5 (p < 0.05) in samples exposed to the electric field. A delayed but two fold increase in ALP and col1 transcript was detected by week 2 (p < 0.05) in differentiating hMSCs exposed to an electric field in comparison to the nonstimulated controls. Upregulation in stress marker, hsp27, and type 1 collagen deposition were correlated with this response. Increases in NADH, FAD, and lipofuscin were traced in the stimulation group during the first week of field exposure with differences statistically significant on day 10 (p < 0.05). Changes in hsp27 expression correlate well with changes in lipofuscin

  18. Acute respiratory bronchiolitis: an ultrastructural and autoradiographic study of epithelial cell injury and renewal in Rhesus monkeys exposed to ozone

    SciTech Connect

    Castleman, W.L.; Dungworth, D.L.; Schwartz, L.W.; Tyler, W.S.

    1980-03-01

    The pathogenesis of acute respiratory bronchiolitis was examined in Rhesus monkeys exposed to 0.8 ppM ozone for 4 to 50 hours. Epithelial injury and renewal were qualitatively and quantitatively characterized by correlated techniques of scanning and transmission electron microscopy as well as by light-microscopic autoradiography following labeling with tritiated thymidine. Extensive degeneration and necrosis of Type 1 epithelial cells occurred on the respiratory bronchiolar wall during the initial 4 to 12 hours of exposure. Increased numbers of labeled epithelial cells were present in this region after 18 hours of exposure, and the highest labeling index (18%) was measured after 50 hours of exposure. Most (67 to 80%) of the labeled cells and all the mitotic epithelial cells (22) observed ultrastructurally were cuboidal bronchiolar epithelial cells. Of the labeled epithelial cells, 20 to 33% were Type 2 epithelial cells. After 50 hours of exposure the respiratory bronchiolar epithelium was hyperplastic. The predominant inflammatory cell in respiratory bronchiolar exudate was the alveolar macrophage. Monkeys that were exposed for 50 hours and allowed to recover in unozonized air for 7 days had incomplete resolution of respiratory bronchiolar epithelial hyperplasia. The results indicate that Type 1 epithelial cells lining respiratory bronchioles are the cell types most sensitive to injury and that both cuboidal bronchiolar epithelial cells and Type 2 epithelial cells function as stem cells in epithelial renewal.

  19. Transcriptomic analysis of cultured whale skin cells exposed to hexavalent chromium [Cr(VI)].

    PubMed

    Pabuwal, Vagmita; Boswell, Mikki; Pasquali, Amanda; Wise, Sandra S; Kumar, Suresh; Shen, Yingjia; Garcia, Tzintzuni; Lacerte, Carolyne; Wise, John Pierce; Wise, John Pierce; Warren, Wesley; Walter, Ronald B

    2013-06-15

    Hexavalent chromium Cr(VI) is known to produce cytotoxic effects in humans and is a highly toxic environmental contaminant. Interestingly, it has been shown that free ranging sperm whales (Phyester macrocephalus) may have exceedingly high levels of Cr in their skin. Also, it has been demonstrated that skin cells from whales appear more resistant to both cytotoxicity and clastogenicity upon Cr exposure compared to human cells. However, the molecular genetic mechanisms employed in whale skin cells that might lead to Cr tolerance are unknown. In an effort to understand the underlying mechanisms of Cr(VI) tolerance and to illuminate global gene expression patterns modulated by Cr, we exposed whale skin cells in culture to varying levels of Cr(VI) (i.e., 0.0, 0.5, 1.0 and 5.0 μg/cm²) followed by short read (100 bp) next generation RNA sequencing (RNA-seq). RNA-seq reads from all exposures (≈280 million reads) were pooled to generate a de novo reference transcriptome assembly. The resulting whale reference assembly had 11K contigs and an N50 of 2954 bp. Using the reads from each dose (0.0, 0.5, 1.0 and 5.0 μg/cm²) we performed RNA-seq based gene expression analysis that identified 35 up-regulated genes and 19 down-regulated genes. The experimental results suggest that low dose exposure to Cr (1.0 μg/cm²) serves to induce up-regulation of oxidative stress response genes, DNA repair genes and cell cycle regulator genes. However, at higher doses (5.0 μg/cm²) the DNA repair genes appeared down-regulated while other genes that were induced suggest the initiation of cytotoxicity. The set of genes identified that show regulatory modulation at different Cr doses provide specific candidates for further studies aimed at determination of how whales exhibit resistance to Cr toxicity and what role(s) reactive oxygen species (ROS) may play in this process. Copyright © 2013 Elsevier B.V. All rights reserved.

  20. Study of Oxidative Stress in Human Lens Epithelial Cells Exposed to 1.8 GHz Radiofrequency Fields

    PubMed Central

    Ni, Shuang; Yu, Yibo; Zhang, Yidong; Wu, Wei; Lai, Kairan; Yao, Ke

    2013-01-01

    Objectives The aims of the present study were to determine oxidative stress and to explore possible reasons of reactive oxygen species (ROS) increase in human lens epithelial (HLE) B3 cells exposed to low intensity 1.8 GHz radiofrequency fields (RF). Methods The HLE B3 cells were divided into RF exposure and RF sham-exposure groups. The RF exposure intensity was at specific absorption rate (SAR) of 2, 3, or 4 W/kg. The ROS levels were measured by a fluorescent probe 2′7′-dichlorofluorescin diacetate (DCFH-DA) assay in the HLE B3 cells exposed to 1.8 GHz RF for 0.5, 1, and 1.5 h. Lipid peroxidation and cellular viability were detected by an MDA test and Cell Counting Kit-8 (CCK-8) assays, respectively, in the HLE B3 cells exposed to 1.8 GHz RF for 6, 12, and 24 h, respectively. The mRNA expression of SOD1, SOD2, CAT, and GPx1 genes and the expression of SOD1, SOD2, CAT, and GPx1 proteins was measured by qRT-PCR and Western blot assays in the HLE B3 cells exposed to 1.8 GHz RF for 1 h. Results The ROS and MDA levels significantly increased (P<0.05) in the RF exposure group and that the cellular viability, mRNA expression of four genes, and expression of four proteins significantly decreased (P<0.05) compared with the RF sham-exposure group. Conclusions Oxidative stress is present in HLE B3 cells exposed to 1.8 GHz low-intensity RF and that the increased production of ROS may be related to down-regulation of four antioxidant enzyme genes induced by RF exposure. PMID:23991100

  1. Study of oxidative stress in human lens epithelial cells exposed to 1.8 GHz radiofrequency fields.

    PubMed

    Ni, Shuang; Yu, Yibo; Zhang, Yidong; Wu, Wei; Lai, Kairan; Yao, Ke

    2013-01-01

    The aims of the present study were to determine oxidative stress and to explore possible reasons of reactive oxygen species (ROS) increase in human lens epithelial (HLE) B3 cells exposed to low intensity 1.8 GHz radiofrequency fields (RF). The HLE B3 cells were divided into RF exposure and RF sham-exposure groups. The RF exposure intensity was at specific absorption rate (SAR) of 2, 3, or 4 W/kg. The ROS levels were measured by a fluorescent probe 2'7'-dichlorofluorescin diacetate (DCFH-DA) assay in the HLE B3 cells exposed to 1.8 GHz RF for 0.5, 1, and 1.5 h. Lipid peroxidation and cellular viability were detected by an MDA test and Cell Counting Kit-8 (CCK-8) assays, respectively, in the HLE B3 cells exposed to 1.8 GHz RF for 6, 12, and 24 h, respectively. The mRNA expression of SOD1, SOD2, CAT, and GPx1 genes and the expression of SOD1, SOD2, CAT, and GPx1 proteins was measured by qRT-PCR and Western blot assays in the HLE B3 cells exposed to 1.8 GHz RF for 1 h. The ROS and MDA levels significantly increased (P<0.05) in the RF exposure group and that the cellular viability, mRNA expression of four genes, and expression of four proteins significantly decreased (P<0.05) compared with the RF sham-exposure group. Oxidative stress is present in HLE B3 cells exposed to 1.8 GHz low-intensity RF and that the increased production of ROS may be related to down-regulation of four antioxidant enzyme genes induced by RF exposure.

  2. Apoptosis of peripheral blood mononuclear cells in children exposed to arsenic and fluoride.

    PubMed

    Rocha-Amador, Diana O; Calderón, Jaqueline; Carrizales, Leticia; Costilla-Salazar, Rogelio; Pérez-Maldonado, Iván Nelinho

    2011-11-01

    In this study, we evaluated apoptosis induction in human immune cells in children exposed to arsenic (As) and fluoride (F). Children living in two areas in Mexico (Soledad de Graciano Sanchez (SGS) in San Luis Potosí and Colonia 5 de Febrero in Durango) were studied. Water, urine and blood samples were collected. Approximately 90% of the water samples in 5 de Febrero had As and F levels above the World Health Organization intervention guideline (10 μg/L and 1.5mg/L, respectively). In SGS, 0% of the water samples exceeded Mexican guidelines. Urinary As and F levels in children living in 5 de Febrero were significantly higher than the levels found in children living in SGS. In addition, the level of apoptosis was higher in children from the 5 de Febrero community when compared with the level of apoptosis in children living in SGS. Thus, in a worldwide context, our study demonstrates the health risks to children living in these regions.

  3. A predictor for toxin-like proteins exposes cell modulator candidates within viral genomes

    PubMed Central

    Naamati, Guy; Askenazi, Manor; Linial, Michal

    2010-01-01

    Motivation: Animal toxins operate by binding to receptors and ion channels. These proteins are short and vary in sequence, structure and function. Sporadic discoveries have also revealed endogenous toxin-like proteins in non-venomous organisms. Viral proteins are the largest group of quickly evolving proteomes. We tested the hypothesis that toxin-like proteins exist in viruses and that they act to modulate functions of their hosts. Results: We updated and improved a classifier for compact proteins resembling short animal toxins that is based on a machine-learning method. We applied it in a large-scale setting to identify toxin-like proteins among short viral proteins. Among the ∼26 000 representatives of such short proteins, 510 sequences were positively identified. We focused on the 19 highest scoring proteins. Among them, we identified conotoxin-like proteins, growth factors receptor-like proteins and anti-bacterial peptides. Our predictor was shown to enhance annotation inference for many ‘uncharacterized’ proteins. We conclude that our protocol can expose toxin-like proteins in unexplored niches including metagenomics data and enhance the systematic discovery of novel cell modulators for drug development. Availability: ClanTox is available at http://www.clantox.cs.huji.ac.il Contact: michall@cc.huji.ac.il PMID:20823311

  4. Ion transport into cells exposed to monopolar and bipolar nanosecond pulses

    PubMed Central

    Schoenbach, Karl H.; Pakhomov, Andrei G.; Semenov, Iurii; Xiao, Shu; Pakhomova, Olga N.; Ibey, Bennet L.

    2014-01-01

    Experiments with CHO cells exposed to 60 and 300 ns pulsed electric fields with amplitudes in the range from several kV/cm to tens of kV/cm, showed a decrease of the uptake of calcium ions by more than an order of magnitude when, immediately after a first pulse, a second one of opposite polarity was applied. This effect is assumed to be due to the reversal of the electrophoretic transport of ions through the electroporated membrane during the second phase of the bipolar pulse. This assumption, however, is only valid if electrophoresis is the dominant transport mechanism, rather than diffusion. Comparison of calculated calcium ion currents with experimental results showed that for nanosecond pulses, electrophoresis is at least as important as diffusion. By delaying the second pulse with respect to the first one, the effect of reverse electrophoresis is reduced. Consequently, separating nanosecond pulses of opposite polarity by up to approximately hundred microseconds allows us to vary the uptake of ions from very small values to that obtained with two pulses of the same polarity. The measured calcium ion uptake obtained with bipolar pulses also allowed us to determine the membrane pore recovery time. The calculated recovery time constants are on the order of ten microseconds. PMID:25212701

  5. Knockout of Ccr2 alleviates photoreceptor cell death in rodent retina exposed to chronic blue light.

    PubMed

    Hu, Zizhong; Zhang, Yi; Wang, Junling; Mao, Pingan; Lv, Xuehua; Yuan, Songtao; Huang, Zhengru; Ding, Yuzhi; Xie, Ping; Liu, Qinghuai

    2016-11-10

    Age-related macular degeneration (AMD), the leading cause of visual loss after the age of 60 years, is a degenerative retinal disease involving a variety of environmental and hereditary factors. Although it has been implicated that immune system is involved in the disease progression, the exact role that microglia has is still unclear. Here we demonstrated that knockout of Ccr2 gene could alleviate photoreceptor cell death in mice retinas exposed to chronic blue light. In Ccr2(-/-) mice, a damaged microglia recruitment was shown in retina and this could protect the visual function in electroretinogram and alleviate the photoreceptor apoptosis, which thus helped attenuate the blue light-induced retinopathy. We further found an increased co-location of NLRP3, Iba-1, and IL-1β in fluorescence and a concomitant increased protein expression of NLRP3, caspase-1, and IL-1β in western blotting in chronic blue light-induced retinopathy. Moreover, the activation of microglia and their cellular NLRP3 inflammasomes occurred as an earlier step before the structural and functional damage of the mice retinas, which collectively supported that microglial NLRP3 inflammasome might be the key to the chronic blue light-induced retinopathy.

  6. [Surface markers and functions of human dendritic cells exposed to mobile phone 1800 MHz electromagnetic fields].

    PubMed

    Zhou, Zhi-dong; Zeng, Qun-li; Zheng, Yun; Zhang, Jian-bin; Chen, Hai-yang; Lu, De-qiang; Shao, Chuan-sen; Xia, Da-jing

    2008-01-01

    To investigate the effects of mobile phone 1800 MHz electromagnetic fields (EMF) on the surface markers and the functions of human dendritic cells (DC). Human DCs were exposed to intermittent 5 min on/10 min off EMF with specific absorption rates (SAR) 4 W/kg for 0 h, 1 h, 12 h or 24 h, respectively. FACS analysis was used to detect the positive percentage of DC surface markers including HLA-DR and co-stimulatory molecules such as CD80, CD86, CD40 and CD11c. CCK-8 kit was adopted to examine the function of allo-mixed lymphocyte reaction (allo-MLR) of DC, and enzyme linked immunosorbent assay (ELISA) to identify the levels of IL-12p70 and TNF-alpha secreted by DC. Compared with the sham radiation group, after exposure to the electromagnetic fields for 1 h, 12 h, or 24 h, HLA-DR, CD80,CD86 and CD40 were all declined except CD11c. The ability of DC allo-MLR in each exposure group was decreased significantly (P<0.05), especially in the 24 h exposure group. However, the secreted levels of IL-12p70 and TNF-alpha of DC in each exposure group remained no changed. The study showed that EMF exposure could down-regulate the surface molecules and stimulation ability of human DC.

  7. Susceptibility of oxidative stress on red blood cells exposed to gamma rays: hemorheological evaluation.

    PubMed

    Kim, Yu-Kyung; Kwon, Eun-Hee; Kim, Dong-Hyun; Won, Dong-Il; Shin, Sehyun; Suh, Jang-Soo

    2008-01-01

    Irradiation has been shown to induce biochemical changes in stored red blood cells (RBCs) and to generate reactive oxygen species (ROS). This study evaluated the hemorheological properties, the degree of lipid peroxidation and the oxidative susceptibility of irradiated RBCs. Furthermore, we investigated the radioprotective role of N-t-butyl hydroxylamine (NtBHA) against gamma-ray exposure of RBCs. RBC concentrates were irradiated with a minimum dose of 25 Gy, and were exposed to FeSO4 to examine the oxidative susceptibility. RBC deformability was evaluated by the use of a microfluidic ektacytometer, in relation to the hematological and biochemical properties. The deformability of the irradiated RBCs was significantly lower than that of control. Exposure to gamma rays significantly increased the mean corpuscular volume (MCV) and lipid peroxidation. Changes in RBC deformability were more prominent in irradiated RBCs than in non-irradiated RBCs also under conditions of oxidative stress. The deformability of NtBHA treated RBCs prior to irradiation was not altered as compared with irradiated RBCs not treated with NtBHA. In conclusion, irradiation reduces RBC deformability during storage and the irradiated RBCs seem susceptible to oxidative stress. NtBHA may not have a protective role against the effects of gamma-ray exposure in RBCs but further evaluation of NtBHA or another radioprotective compound is required.

  8. Ion transport into cells exposed to monopolar and bipolar nanosecond pulses.

    PubMed

    Schoenbach, Karl H; Pakhomov, Andrei G; Semenov, Iurii; Xiao, Shu; Pakhomova, Olga N; Ibey, Bennett L

    2015-06-01

    Experiments with CHO cells exposed to 60 and 300 ns pulsed electric fields with amplitudes in the range from several kV/cm to tens of kV/cm showed a decrease of the uptake of calcium ions by more than an order of magnitude when, immediately after a first pulse, a second one of opposite polarity was applied. This effect is assumed to be due to the reversal of the electrophoretic transport of ions through the electroporated membrane during the second phase of the bipolar pulse. This assumption, however, is only valid if electrophoresis is the dominant transport mechanism, rather than diffusion. Comparison of calculated calcium ion currents with experimental results showed that for nanosecond pulses, electrophoresis is at least as important as diffusion. By delaying the second pulse with respect to the first one, the effect of reverse electrophoresis is reduced. Consequently, separating nanosecond pulses of opposite polarity by up to approximately hundred microseconds allows us to vary the uptake of ions from very small values to those obtained with two pulses of the same polarity. The measured calcium ion uptake obtained with bipolar pulses also allowed us to determine the membrane pore recovery time. The calculated recovery time constants are on the order of 10 μs.

  9. Speciation of arsenic in Euglena gracilis cells exposed to As(V).

    PubMed

    Miot, Jennyfer; Morin, Guillaume; Skouri-Panet, Fériel; Férard, Céline; Poitevin, Antonine; Aubry, Emmanuel; Ona-Nguema, Georges; Juillot, Farid; Guyot, François; Brown, Gordon E

    2009-05-01

    Euglena gracilis is a photosynthetic eukaryote ubiquitous in arsenic-polluted acid mine drainages and is locally exposed to As(III) and As(V) concentrations up to 250 and 100 mg L(-1), respectively. Here, arsenic speciation in E. graciliswas determined by X-ray absorption spectroscopy and selected (bio)chemical methods on cells grown at nonlimiting phosphate concentrations. Our results suggest the following detoxification scheme: (1) uptake of As(V) from solution in competition with phosphate, (2) intracellular reduction to As(III), (3) complexation by cytoplasmic proteic thiol ligands of low molecular weight, and (4) As(III) export from the cell. However, at As(V) concentrations >100 mg L(-1), growth rate is markedly lowered and As(V) remains mostly unreduced during the extended lag period. Intracellular As(V) is found to be exclusively concentrated in the membrane + nucleus fraction, suggesting that arsenate could substitute for phosphate groups in membranes or in phosphate-containing macromolecules. Thus, arsenic species are partitioned, with As(III)-thiol compounds concentrated in the cytoplasmic proteic pool and As(V)-compounds associated with the membrane + nucleus fraction. The increasing growth delay observed with increasing initial As(V) concentration in the culture medium is proposed to result from the combination of a higher As(V) uptake and limiting intracellular As(V) reduction rate and As(III) export rate. Under high As(V) exposure conditions (200 mg L(-1)) the reduction step is found to be the most limiting step for detoxification.

  10. Persistent oxidative stress in human neural stem cells exposed to low fluences of charged particles.

    PubMed

    Baulch, Janet E; Craver, Brianna M; Tran, Katherine K; Yu, Liping; Chmielewski, Nicole; Allen, Barrett D; Limoli, Charles L

    2015-08-01

    Exposure to the space radiation environment poses risks for a range of deleterious health effects due to the unique types of radiation encountered. Galactic cosmic rays are comprised of a spectrum of highly energetic nuclei that deposit densely ionizing tracks of damage along the particle trajectory. These tracks are distinct from those generated by the more sparsely ionizing terrestrial radiations, and define the geometric distribution of the complex cellular damage that results when charged particles traverse the tissues of the body. The exquisite radiosensitivity of multipotent neural stem and progenitor cells found within the neurogenic regions of the brain predispose the central nervous system to elevated risks for radiation induced sequelae. Here we show that human neural stem cells (hNSC) exposed to different charged particles at space relevant fluences exhibit significant and persistent oxidative stress. Radiation induced oxidative stress was found to be most dependent on total dose rather than on the linear energy transfer of the incident particle. The use of redox sensitive fluorogenic dyes possessing relative specificity for hydroxyl radicals, peroxynitrite, nitric oxide (NO) and mitochondrial superoxide confirmed that most irradiation paradigms elevated reactive oxygen and nitrogen species (ROS and RNS, respectively) in hNSC over a 1 week interval following exposure. Nitric oxide synthase (NOS) was not the major source of elevated nitric oxides, as the use of NOS inhibitors had little effect on NO dependent fluorescence. Our data provide extensive evidence for the capability of low doses of charged particles to elicit marked changes in the metabolic profile of irradiated hNSC. Radiation induced changes in redox state may render the brain more susceptible to the development of neurocognitive deficits that could affect an astronaut's ability to perform complex tasks during extended missions in deep space. Copyright © 2015 The Authors. Published by

  11. Persistent oxidative stress in human neural stem cells exposed to low fluences of charged particles

    PubMed Central

    Baulch, Janet E.; Craver, Brianna M.; Tran, Katherine K.; Yu, Liping; Chmielewski, Nicole; Allen, Barrett D.; Limoli, Charles L.

    2015-01-01

    Exposure to the space radiation environment poses risks for a range of deleterious health effects due to the unique types of radiation encountered. Galactic cosmic rays are comprised of a spectrum of highly energetic nuclei that deposit densely ionizing tracks of damage along the particle trajectory. These tracks are distinct from those generated by the more sparsely ionizing terrestrial radiations, and define the geometric distribution of the complex cellular damage that results when charged particles traverse the tissues of the body. The exquisite radiosensitivity of multipotent neural stem and progenitor cells found within the neurogenic regions of the brain predispose the central nervous system to elevated risks for radiation induced sequelae. Here we show that human neural stem cells (hNSC) exposed to different charged particles at space relevant fluences exhibit significant and persistent oxidative stress. Radiation induced oxidative stress was found to be most dependent on total dose rather than on the linear energy transfer of the incident particle. The use of redox sensitive fluorogenic dyes possessing relative specificity for hydroxyl radicals, peroxynitrite, nitric oxide (NO) and mitochondrial superoxide confirmed that most irradiation paradigms elevated reactive oxygen and nitrogen species (ROS and RNS, respectively) in hNSC over a 1 week interval following exposure. Nitric oxide synthase (NOS) was not the major source of elevated nitric oxides, as the use of NOS inhibitors had little effect on NO dependent fluorescence. Our data provide extensive evidence for the capability of low doses of charged particles to elicit marked changes in the metabolic profile of irradiated hNSC. Radiation induced changes in redox state may render the brain more susceptible to the development of neurocognitive deficits that could affect an astronaut’s ability to perform complex tasks during extended missions in deep space. PMID:25800120

  12. Fibrogenic response of hepatic stellate cells in ovariectomised rats exposed to ketogenic diet.

    PubMed

    Bobowiec, R; Wojcik, M; Jaworska-Adamu, J; Tusinska, E

    2013-02-01

    The discrepancy about the role of estrogens in hepatic fibrogenesis and lack of studies addressed of ketogenic diet (KD) on hepatic stellate cells (HSC), prompted us to investigate the activity of HSC in control, KD- and thioacetamide (TAA)-administrated rats with different plasma concentration of estradiol (E2). HSC were isolated by the collagenase perfusion methods and separated by the Percoll gradient centrifugation. After the 4(th) and 8(th) day of incubation, lysates of HSC and the media were collected for further analysis. The HSC derived from KD-rats released remarkably more transforming growth factor (TGF)-β1 than cells obtained from animals fed with a standard diet. The ovariectomy of KD-rats markedly intensified the secretion of this fibrogenic cytokine on the 8(th) day of incubation (201.33 ±1 7.15 pg/ml). In HSC of rats exposed to E2, the TGF-β1 concentration did not exceed 157 ± 34.39 pg/ml. In respect to the collagen type I, the HSC obtained from ovariectomised KD-rats released an augmented amount of this ECM protein after the 8(th) day of culture (1.83 ± 0.14 U/ml). In the same time, higher quantities of ASMA appeared in the KD rats (1.41 ± 0.3 pg/mg protein). Exposition of rats to E2 did not markedly decrease the amount of ASMA. In summary, KD was able to induce morphological and functional changes in HSC, especially derived from rats deprived of ovarian estrogens. However, the preservation of E2 in ovariectomised rats didn't substantially alter the activation of HSC.

  13. Host cell reactivation of sunlamp-exposed adenovirus in fibroblasts from patients with Bloom's syndrome, ataxia telangiectasia, and Huntington's disease

    SciTech Connect

    Rainbow, A.J. )

    1991-01-01

    In this study, a sensitive host cell reactivation (HCR) technique was used to examine the repair capacity for DNA damaged by sunlamp exposure in fibroblast strains derived from 5 normal individuals and 8 patients representing three different diseases associated with DNA repair deficiencies. Adenovirus type 2 (Ad 2) was exposed to radiation from a GE 275 W sunlamp and subsequently used to infect fibroblast monolayers. At 48 hr after infection, cells were scored for the presence of viral structural antigens (Vag) using indirect immunofluorescent staining. Previous reports using this technique showed a substantial reduction in the HCR of sunlamp-exposed Ad 2 for infection of excision repair deficient fibroblasts from patients with xeroderma pigmentosum. In contrast, the HCR of Vag synthesis for sunlamp-exposed Ad 2 was in the normal range for the three ataxia telangiectasia, three Bloom's syndrome, and two Huntington's disease fibroblasts strains.

  14. B cells play key roles in th2-type airway immune responses in mice exposed to natural airborne allergens.

    PubMed

    Drake, Li Yin; Iijima, Koji; Hara, Kenichiro; Kobayashi, Takao; Kephart, Gail M; Kita, Hirohito

    2015-01-01

    Humans are frequently exposed to various airborne allergens. In addition to producing antibodies, B cells participate in immune responses via various mechanisms. The roles of B cells in allergic airway inflammation and asthma have been controversial. We examined the functional importance of B cells in a mouse model of asthma, in which mice were exposed repeatedly to common airborne allergens. Naïve wild-type BALB/c mice or B cell-deficient JH-/- mice were exposed intranasally to a cocktail of allergen extracts, including Alternaria, Aspergillus, and house dust mite, every other day for two weeks. Ovalbumin was included in the cocktail to monitor the T cell immune response. Airway inflammation, lung pathology, and airway reactivity were analyzed. The airway exposure of naïve wild type mice to airborne allergens induced robust eosinophilic airway inflammation, increased the levels of Th2 cytokines and chemokines in the lung, and increased the reactivity to inhaled methacholine. These pathological changes and immune responses were attenuated in B cell-deficient JH-/- mice. The allergen-induced expansion of CD4+ T cells was impaired in the lungs and draining lymph nodes of JH-/- mice. Furthermore, lymphocytes from JH-/- mice failed to produce Th2 cytokines in response to ovalbumin re-stimulation in vitro. Our results suggest that B cells are required for the optimal development of Th2-type immune responses and airway inflammation when exposed to common airborne allergens. The therapeutic targeting of B cells may be beneficial to treat asthma in certain patients.

  15. The effect of 50 Hz electromagnetic fields on the formation of micronuclei in rodent cell lines exposed to gamma radiation.

    PubMed

    Lagroye, I; Poncy, J L

    1997-08-01

    Low frequency electromagnetic fields (EMF) do not produce enough energy to damage DNA, in contrast to ionizing radiations. Any relationship between increased incidence of cancer and EMF must therefore be explained by a promoting effect on cellular transformation by ionizing radiation. The aim of this study was to investigate using the cytokinesis-blocked micronucleus assay a possible amplification of the genotoxic effects of ionizing radiations in cells exposed to combined static and power-frequency electromagnetic fields. Rat tracheal epithelial cell lines were first exposed in vitro to 60Co gamma rays (0, 2 and 6 Gy) and cells were then cultured for 24 h in a homogeneous sinusoidal 50 Hz magnetic field (flux density: 100 microTrms) combined with an artificial geomagnetic-like field created by the use of horizontal and vertical pairs of Helmholtz coils. Control cells were cultured in an adjacent incubator where the background EMF was about 0.1 microTrms. Under our in vitro experimental conditions, EMF appeared to have no significant direct effect on micronucleus induction in rat tracheal cell lines. However, an increased frequency of binucleated cells with micronuclei was observed in cells exposed to 6 Gy of gamma rays and EMF, compared with gamma irradiation alone. This could enhance radiation-induced genomic alterations and increase the probability of neoplastic transformation.

  16. Glycophorin A somatic cell mutation frequencies in Finnish reinforced plastics workers exposed to styrene.

    PubMed

    Bigbee, W L; Grant, S G; Langlois, R G; Jensen, R H; Anttila, A; Pfäffli, P; Pekari, K; Norppa, H

    1996-10-01

    We have used the glycophorin A (GPA) in vivo somatic cell mutation assay to assess the genotoxic potential of styrene exposure in 47 reinforced plastics workers occupationally exposed to styrene and 47 unexposed controls matched for age, gender, and active smoking status. GPA variant erythrocyte frequencies (Vf), reflecting GPA allele loss (phi/N) and allele loss and duplication (N/N) somatic mutations arising in vivo in the erythroid progenitor cells of individuals of GPA M/N heterozygous genotype, were flow cytometrically determined in peripheral blood samples from these subjects. Measurements of styrene exposure of the workers at the time of blood sampling showed a mean 8-h time-weighted average (TWA8-h) styrene concentration of 155 mg/m3 (37 ppm) in the breathing zone. Mean urinary concentrations of the styrene metabolites mandelic acid (MA) and mandelic acid plus phenyl glyoxylic acid (MA+PGA) were 4.4 mmol/liter (after workshift) and 2.1 mmol/liter (next morning), respectively. Multivariate analysis of covariance on log-transformed GPA Vf data with models allowing adjustment for age, gender, smoking status, and styrene exposure showed that N/N Vf were nearly significantly increased among all of the exposed workers (adjusted geometric mean, 6.3 per million versus 5.0 in the controls; P = 0.058) and were statistically significantly elevated (adjusted geometric mean, 6.8 versus 5.0 in the controls; P = 0.036) among workers classified into a high-exposure group according to personal TWA8-h concentration of styrene in the breathing zone of > or = 85 mg/m3 (20 ppm; Finnish threshold limit value). Women in this high exposure group showed especially elevated N/N Vf (adjusted geometric mean 8.5 versus 5.3 in control women; P = 0.020); this elevation was also significant if urinary MA+PGA of > or = 1.2 mmol/liter was used as the basis of classification (adjusted geometric mean, 8.3; P = 0.030). The occupational exposure could not be shown to influence phi/N Vf

  17. Cytogenetic biomonitoring of Brazilian workers exposed to pesticides: micronucleus analysis in buccal epithelial cells of soybean growers.

    PubMed

    Bortoli, Giorgia Moura de; Azevedo, Mariana Barbieri de; Silva, Luciano Basso da

    2009-04-30

    Pesticides have been considered potential chemical mutagens and various agrochemical ingredients possess mutagenic properties. Biomonitoring provides a useful tool to estimate the genetic risk from exposure to a complex mixture of chemicals. In general genetic damage associated with pesticides occurs in human populations subject to high exposure levels due to intensive use, misuse or failure of control measures. Few studies have been carried out using the micronucleus (MN) analysis in buccal cells of farm workers and, from the available data, only one has found a positive relationship. Micronuclei were analyzed in 29 Brazilian workers exposed to pesticides in soybean fields and in 37 non-exposed individuals. The results obtained indicate that the mean number of cells with MN in the exposed group (3.55+/-2.13) was significantly higher than in the control group (1.78+/-1.23). The number of cells with MN was not influenced by age, smoking habit, smoking time, number of cigarettes/day, alcohol consumption and years of exposure to pesticides. The genotoxic potential of the pesticides used in soybean fields may explain the detectable increase of cells with MN in exposed workers.

  18. IN VITRO EFFECTS OF PARTICULATE MATTER ON AIRWAY EPITHELIAL CELLS ISOLATED FROM CONCENTRATED AIR PARTICLES-EXPOSED SPONTANEOUS HYPERTENSIVE RATS

    EPA Science Inventory

    In vitro effects of particulate matter on airway epithelial cells isolated from concentrated air particles-exposed spontaneous hypertensive rats

    Ines Pagan, Urmila Kodavanti, Paul Evansky, Daniel L Costa and Janice A Dye. U.S. Environmental Protection Agency, ORD, National...

  19. GENE EXPRESSION PROFILES IN HUMAN AND RAT VASCULAR ENDOTHELIAL CELLS EXPOSED TO RESIDUAL OIL FLY ASH (ROFA) AND VANADIUM (V)

    EPA Science Inventory

    Gene expression profiles in human and rat vascular endothelial cells exposed to residual oil fly ash (ROFA) or vanadium (V).
    Srikanth S. Nadadur, Darrell W. Winsett and Daniel L. Costa, US EPA, ORD, NHEERL (ETD, Pulmonary Toxicology Branch), Research Triangle Park, NC 27711.

  20. IN VITRO EFFECTS OF PARTICULATE MATTER ON AIRWAY EPITHELIAL CELLS ISOLATED FROM CONCENTRATED AIR PARTICLES-EXPOSED SPONTANEOUS HYPERTENSIVE RATS

    EPA Science Inventory

    In vitro effects of particulate matter on airway epithelial cells isolated from concentrated air particles-exposed spontaneous hypertensive rats

    Ines Pagan, Urmila Kodavanti, Paul Evansky, Daniel L Costa and Janice A Dye. U.S. Environmental Protection Agency, ORD, National...

  1. GENE EXPRESSION PROFILES IN HUMAN AND RAT VASCULAR ENDOTHELIAL CELLS EXPOSED TO RESIDUAL OIL FLY ASH (ROFA) AND VANADIUM (V)

    EPA Science Inventory

    Gene expression profiles in human and rat vascular endothelial cells exposed to residual oil fly ash (ROFA) or vanadium (V).
    Srikanth S. Nadadur, Darrell W. Winsett and Daniel L. Costa, US EPA, ORD, NHEERL (ETD, Pulmonary Toxicology Branch), Research Triangle Park, NC 27711.

  2. Effect of angiopoietin-like protein 4 on rat pulmonary microvascular endothelial cells exposed to LPS

    PubMed Central

    WANG, YUXI; CHEN, HAILONG; LI, HAILONG; ZHANG, JINGWEN; GAO, YANYAN

    2013-01-01

    Pulmonary microvascular endothelial cells (PMVECs) possess highly proliferative and angiogenic capacities and are localized at the critical interface between the blood and microvessel wall; they are the primary targets of inflammatory cytokines during lung inflammation. Angiopoietin-like protein 4 (Angptl4) is a circulating protein that has recently been implicated in the regulation of angiogenesis and metastasis. This study aimed to investigate the effect of Angptl4 on rat PMVECs (RPMVECs) exposed to lipopolysaccharide (LPS). The cell culture was stimulated with LPS. Total Angptl4 cDNA was obtained from Source BioScience. The PCR product was cloned into the pcDNA3.1-eGFP or the pcDNA3.1-eGFP-Angptl4 vector, which were then transfected into the RPMVECs using SuperFect transfection reagent. The Angptl4 mRNA levels, protein levels and cell morphology of the RPMVECs in the experimental groups were detected using real time-PCR, western blot analysis, MTT assay, ELISA and confocal microscopy methods, respectively. The Angptl4 expression vector, pcDNA3.1-eGFP-Angptl4, was successfully constructed. The Angptl4 mRNA level in the LPS-pcDNA3.1-eGFP-transfected group (blank control) was slightly increased and was significantly higher in the experimental group compared with the empty vector and blank control group with significant differences. Pro-apoptotic caspase-8, -9 and Bax protein were inhibited, while p-AKT/AKT and p-MEK1/2 protein expression was also decreased. The rosiglitazone group had significantly decreased levels of the inflammatory cytokine, tumor necrosis factor (TNF)-α (P<0.01). The overexpression of Angptl4 inhibited the LPS-induced increase in the permeability of the RPMVECs, which was associated with the depolymerization of central F-actin in the RPMVECs. In conclusion, our study demonstrates that the overexpression of Angptl4 exerts protective, anti-inflammatory and anti-angiogenic effects. It represents a novel therapeutic target gene for the treatment

  3. Responses of well-differentiated nasal epithelial cells exposed to particles: Role of the epithelium in airway inflammation

    SciTech Connect

    Auger, Floriane; Gendron, Marie-Claude; Chamot, Christophe; Marano, Francelyne; Dazy, Anne-Catherine . E-mail: dazy@paris7.jussieu.fr

    2006-09-15

    Numerous epidemiological studies support the contention that ambient air pollution particles can adversely affect human health. To explain the acute inflammatory process in airways exposed to particles, a number of in vitro studies have been performed on cells grown submerged on plastic and poorly differentiated, and on cell lines, the physiology of which is somewhat different from that of well-differentiated cells. In order to obtain results using a model system in which epithelial cells are similar to those of the human airway in vivo, apical membranes of well-differentiated human nasal epithelial (HNE) cells cultured in an air-liquid interface (ALI) were exposed for 24 h to diesel exhaust particles (DEP) and Paris urban air particles (PM{sub 2.5}). DEP and PM{sub 2.5} (10-80 {mu}g/cm{sup 2}) stimulated both IL-8 and amphiregulin (ligand of EGFR) secretion exclusively towards the basal compartment. In contrast, there was no IL-1{beta} secretion and only weak non-reproducible secretion of TNF-{alpha}. IL-6 and GM-CSF were consistently stimulated towards the apical compartment and only when cells were exposed to PM{sub 2.5}. ICAM-1 protein expression on cell surfaces remained low after particle exposure, although it increased after TNF-{alpha} treatment. Internalization of particles, which is believed to initiate oxidative stress and proinflammatory cytokine expression, was restricted to small nanoparticles ({<=} 40 nm). Production of reactive oxygen species (ROS) was detected, and DEP were more efficient than PM{sub 2.5}. Collectively, our results suggest that airway epithelial cells exposed to particles augment the local inflammatory response in the lung but cannot alone initiate a systemic inflammatory response.

  4. [Effect of phosgene on apoptosis of alveolar type II cells and vascular endothelial growth factor in exposed mice].

    PubMed

    Li, Wen-li; Hai, Chun-xu; Qin, Xu-jun; Liang, Xin; Chen, Hong-li

    2004-06-01

    To study the apoptosis of alveolar type II cells, alterations of vascular endothelial growth factor (VEGF), VEGF receptor (Flt1) in serum and lung and expression of VEGF mRNA in lung in pulmonary edema mice induced by phosgene. Twenty-six BALB/C mice were randomly divided into 2 groups: control group, exposed group (13 mice in each group). Mice of exposed group were intoxicated by inhalation of phosgene 11.9 mg/L for 5 minutes. Mice of control group were treated as the same way by inhalation of air. Isolation of mice alveolus type II cells 4 h after intoxication was carried out to observe their apoptosis under electron microscope. Contents of VEGF and Flt1 in lung and serum by ELISA, and expression of VEGF mRNA were determined. Alveolar type II cells were identified by tannic acid staining and electron microscopy. After exposed to 11.9 mg/L of phosgene for 5 minutes, the apoptotic body in alveolus type II cells was found in exposed group. The contents of VEGF in serum and lung and Flt1 in lung of exposed mice [(134.07 +/- 120.26), (477.76 +/- 98.06), (1,2818.48 +/- 2,304.15) pg/ml] were significantly lower than those of control group [(445.57 +/- 173.30), (1,026.87 +/- 474.56), (21,976.51 +/- 7,421.01) pg/ml, P < 0.05] but the content of Flt1 in serum [(2,369.56 +/- 381.70) pg/ml] was higher than that in control group [(1,898.00 +/- 453.69) pg/ml, P < 0.05]. The expression of VEGF mRNA in pulmonary edema mice was decreased. Phosgene can induce apoptosis of alveolar type II cells, and decrease in the content of VEGF and Flt1, and expression of VEGF mRNA in lung.

  5. White blood cell DNA adducts in a cohort of asthmatic children exposed to environmental tobacco smoke.

    PubMed

    Wilson, Stephen E; Talaska, Glenn; Kahn, Robert S; Schumann, Brenda; Khoury, Jane; Leonard, Anthony C; Lanphear, Bruce P

    2011-01-01

    Exposure to environmental tobacco smoke (ETS) leads to molecular damage in the form of DNA adducts. While lung cancer risk is higher among African Americans compared to White Americans, a few studies have tested for racial differences in DNA adducts among children exposed to ETS. The purpose of this study was to test whether African American children have higher DNA adducts levels compared to White children adjusted for ETS exposure. Data and biologic specimens were drawn from an existing cohort of 212 asthmatic children. These subjects participated in a 12-month ETS-reduction trial that employed HEPA air cleaners with active filter cartridges and sham filter cartridges. White blood cell (WBC) DNA was analyzed for DNA adducts using (32)P-postlabeling. We assessed ETS exposure using a validated air nicotine dosimeter. We determined the independent relationship between African American race and DNA adduct levels adjusted for ETS exposure and air cleaner use. The mean age of the subjects was 8.4 years; 55% were African American. There was no difference in DNA adduct levels between African American and White children (11.8 vs. 11.2 adducts per 10(9) nucleotides, p = 0.86), despite slightly higher levels of air nicotine exposure (3.4 vs. 2.2 μg/m(3), p = 0.14). African American children used their air cleaners less often than White children. We found that the best predictor of DNA adduct levels was the duration of air cleaner use (r = -0.133, p = 0.056). This association was independent of cartridge type. We did not see differences in adduct levels by race even after accounting for the level of ETS exposure. However, there was a marginal inverse association between air cleaner use and adducts. Additional research is required to understand this phenomenon.

  6. Relationship of CD86 surface marker expression and cytotoxicity on dendritic cells exposed to chemical allergen

    SciTech Connect

    Hulette, Ben C.; Ryan, Cindy A.; Gildea, Lucy A.; Gerberick, G. Frank . E-mail: gerberick.gf@pg.com

    2005-12-01

    Human peripheral blood-derived dendritic cells (DC) respond to a variety of chemical allergens by up-regulating expression of the co-stimulatory molecule CD86. It has been postulated that this measure might provide the basis for an in vitro alternative approach for the identification of skin sensitizing chemicals. We recently reported that DC, exposed in culture to the highest non-cytotoxic concentrations of various chemical allergens, displayed marginal up-regulation of membrane CD86 expression; the interpretation being that such changes were insufficiently sensitive for the purposes of hazard identification. For the work presented here, immature DC were derived from human monocytes and treated with the chemical allergens 2,4-dinitrobenzenesulfonic acid (DNBS), nickel sulfate (NiSO{sub 4}), p-phenylenediamine (PPD), Bandrowski's base (BB), hydroquinone (HQ) and propyl gallate (PG) for 48 h at concentrations which induced both no to slight to moderate cytotoxicity. For comparison, DC were treated with the irritants sodium dodecyl sulfate (SDS), benzoic acid (BA), and benzalkonium chloride (BZC) at concentrations resulting in comparable levels of cytotoxicity. CD86 expression, as measured by flow cytometry, was consistently up-regulated (ranging from 162 to 386% control) on DC treated with concentrations of chemical allergens that induced approximately 10-15% cytotoxicity. The irritants BA and BZC did not induce up-regulation of CD86 expression when tested at concentrations that induced similar levels of cytotoxicity. SDS, however, up-regulated CD86 expression to 125-138% of control in 2/4 preparations when tested at concentrations which induced similar toxicity. Our results confirm that chemical allergens up-regulate CD86 expression on blood-derived DC and illustrate further that up-regulation of CD86 surface marker expression is more robust when DC are treated with concentrations of chemical allergen that induce slight to moderate cytotoxicity.

  7. White blood cell DNA adducts in a cohort of asthmatic children exposed to environmental tobacco smoke

    PubMed Central

    Talaska, Glenn; Kahn, Robert S.; Schumann, Brenda; Khoury, Jane; Leonard, Anthony C.; Lanphear, Bruce P.

    2010-01-01

    Purpose Exposure to environmental tobacco smoke (ETS) leads to molecular damage in the form of DNA adducts. While lung cancer risk is higher among African Americans compared to White Americans, a few studies have tested for racial differences in DNA adducts among children exposed to ETS. The purpose of this study was to test whether African American children have higher DNA adducts levels compared to White children adjusted for ETS exposure. Methods Data and biologic specimens were drawn from an existing cohort of 212 asthmatic children. These subjects participated in a 12-month ETS-reduction trial that employed HEPA air cleaners with active filter cartridges and sham filter cartridges. White blood cell (WBC) DNA was analyzed for DNA adducts using 32P-postlabeling. We assessed ETS exposure using a validated air nicotine dosimeter. We determined the independent relationship between African American race and DNA adduct levels adjusted for ETS exposure and air cleaner use. Results The mean age of the subjects was 8.4 years; 55% were African American. There was no difference in DNA adduct levels between African American and White children (11.8 vs. 11.2 adducts per 109 nucleotides, p = 0.86), despite slightly higher levels of air nicotine exposure (3.4 vs. 2.2 μg/m3, p = 0.14). African American children used their air cleaners less often than White children. We found that the best predictor of DNA adduct levels was the duration of air cleaner use (r = −0.133, p = 0.056). This association was independent of cartridge type. Conclusions We did not see differences in adduct levels by race even after accounting for the level of ETS exposure. However, there was a marginal inverse association between air cleaner use and adducts. Additional research is required to understand this phenomenon. PMID:20336464

  8. BIGEL analysis of gene expression in HL60 cells exposed to X rays or 60 Hz magnetic fields

    NASA Technical Reports Server (NTRS)

    Balcer-Kubiczek, E. K.; Zhang, X. F.; Han, L. H.; Harrison, G. H.; Davis, C. C.; Zhou, X. J.; Ioffe, V.; McCready, W. A.; Abraham, J. M.; Meltzer, S. J.

    1998-01-01

    We screened a panel of 1,920 randomly selected cDNAs to discover genes that are differentially expressed in HL60 cells exposed to 60 Hz magnetic fields (2 mT) or X rays (5 Gy) compared to unexposed cells. Identification of these clones was accomplished using our two-gel cDNA library screening method (BIGEL). Eighteen cDNAs differentially expressed in X-irradiated compared to control HL60 cells were recovered from a panel of 1,920 clones. Differential expression in experimental compared to control cells was confirmed independently by Northern blotting of paired total RNA samples hybridized to each of the 18 clone-specific cDNA probes. DNA sequencing revealed that 15 of the 18 cDNA clones produced matches with the database for genes related to cell growth, protein synthesis, energy metabolism, oxidative stress or apoptosis (including MYC, neuroleukin, copper zinc-dependent superoxide dismutase, TC4 RAS-like protein, peptide elongation factor 1alpha, BNIP3, GATA3, NF45, cytochrome c oxidase II and triosephosphate isomerase mRNAs). In contrast, BIGEL analysis of the same 1,920 cDNAs revealed no differences greater than 1.5-fold in expression levels in magnetic-field compared to sham-exposed cells. Magnetic-field-exposed and control samples were analyzed further for the presence of mRNA encoding X-ray-responsive genes by hybridization of the 18 specific cDNA probes to RNA from exposed and control HL60 cells. Our results suggest that differential gene expression is induced in approximately 1% of a random pool of cDNAs by ionizing radiation but not by 60 Hz magnetic fields under the present experimental conditions.

  9. BIGEL analysis of gene expression in HL60 cells exposed to X rays or 60 Hz magnetic fields

    NASA Technical Reports Server (NTRS)

    Balcer-Kubiczek, E. K.; Zhang, X. F.; Han, L. H.; Harrison, G. H.; Davis, C. C.; Zhou, X. J.; Ioffe, V.; McCready, W. A.; Abraham, J. M.; Meltzer, S. J.

    1998-01-01

    We screened a panel of 1,920 randomly selected cDNAs to discover genes that are differentially expressed in HL60 cells exposed to 60 Hz magnetic fields (2 mT) or X rays (5 Gy) compared to unexposed cells. Identification of these clones was accomplished using our two-gel cDNA library screening method (BIGEL). Eighteen cDNAs differentially expressed in X-irradiated compared to control HL60 cells were recovered from a panel of 1,920 clones. Differential expression in experimental compared to control cells was confirmed independently by Northern blotting of paired total RNA samples hybridized to each of the 18 clone-specific cDNA probes. DNA sequencing revealed that 15 of the 18 cDNA clones produced matches with the database for genes related to cell growth, protein synthesis, energy metabolism, oxidative stress or apoptosis (including MYC, neuroleukin, copper zinc-dependent superoxide dismutase, TC4 RAS-like protein, peptide elongation factor 1alpha, BNIP3, GATA3, NF45, cytochrome c oxidase II and triosephosphate isomerase mRNAs). In contrast, BIGEL analysis of the same 1,920 cDNAs revealed no differences greater than 1.5-fold in expression levels in magnetic-field compared to sham-exposed cells. Magnetic-field-exposed and control samples were analyzed further for the presence of mRNA encoding X-ray-responsive genes by hybridization of the 18 specific cDNA probes to RNA from exposed and control HL60 cells. Our results suggest that differential gene expression is induced in approximately 1% of a random pool of cDNAs by ionizing radiation but not by 60 Hz magnetic fields under the present experimental conditions.

  10. Study of acetylcholinesterase activity and apoptosis in SH-SY5Y cells and mice exposed to ethanol.

    PubMed

    Sun, Wenjun; Chen, Liangjing; Zheng, Wei; Wei, Xiaoan; Wu, Wenqi; Duysen, Ellen G; Jiang, Wei

    2017-06-01

    Ethanol is one of the most commonly abused psychotropic substances with deleterious effects on the central nervous system. Ethanol exposure during development results in the loss of neurons in brain regions and when exposed to ethanol cultured cells undergo apoptosis. To date no information is available on whether abnormally high AChE activity is characteristic of apoptosis in animals exposed to ethanol. The aims of the present study were to determine whether induction of AChE activity is associated with ethanol-induced apoptosis and to explore the mechanism of enhanced AChE activity induced by ethanol. For this purpose, in vitro and in vivo experiments were performed. AChE activity was quantified by spectrophotometry and apoptosis by flow cytometer in SH-SY5Y cells exposed to ethanol. The results showed that cells treated with 500mM ethanol for 24h had a 9-fold increase in apoptotic cells and a 6-fold increase in AChE activity compared with controls. Mice exposed acutely to 200μl of 20% ethanol daily on days 1-4 had elevated AChE activity in plasma on days 3-7. On day 4, plasma AChE activity was 2.4-fold higher than pretreatment activity. More apoptotic cells were found in the brains of treated mice compared to controls. Cells in brain sections that were positive in the TUNEL assay stained for AChE activity. In conclusion, AChE activity and apoptosis were induced in SH-SY5Y cells and mice treated with ethanol, which may indicate that increased AChE may related to apoptosis induced by ethanol. Unusually high AChE activity may be an effect marker of exposure to ethanol. The relationship between AChE and apoptosis might represent a novel mechanism of ethanol-associated neuronal injury. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. BIGEL analysis of gene expression in HL60 cells exposed to X rays or 60 Hz magnetic fields.

    PubMed

    Balcer-Kubiczek, E K; Zhang, X F; Han, L H; Harrison, G H; Davis, C C; Zhou, X J; Ioffe, V; McCready, W A; Abraham, J M; Meltzer, S J

    1998-12-01

    We screened a panel of 1,920 randomly selected cDNAs to discover genes that are differentially expressed in HL60 cells exposed to 60 Hz magnetic fields (2 mT) or X rays (5 Gy) compared to unexposed cells. Identification of these clones was accomplished using our two-gel cDNA library screening method (BIGEL). Eighteen cDNAs differentially expressed in X-irradiated compared to control HL60 cells were recovered from a panel of 1,920 clones. Differential expression in experimental compared to control cells was confirmed independently by Northern blotting of paired total RNA samples hybridized to each of the 18 clone-specific cDNA probes. DNA sequencing revealed that 15 of the 18 cDNA clones produced matches with the database for genes related to cell growth, protein synthesis, energy metabolism, oxidative stress or apoptosis (including MYC, neuroleukin, copper zinc-dependent superoxide dismutase, TC4 RAS-like protein, peptide elongation factor 1alpha, BNIP3, GATA3, NF45, cytochrome c oxidase II and triosephosphate isomerase mRNAs). In contrast, BIGEL analysis of the same 1,920 cDNAs revealed no differences greater than 1.5-fold in expression levels in magnetic-field compared to sham-exposed cells. Magnetic-field-exposed and control samples were analyzed further for the presence of mRNA encoding X-ray-responsive genes by hybridization of the 18 specific cDNA probes to RNA from exposed and control HL60 cells. Our results suggest that differential gene expression is induced in approximately 1% of a random pool of cDNAs by ionizing radiation but not by 60 Hz magnetic fields under the present experimental conditions.

  12. Differential effects in cells exposed to ultra-short, high intensity electric fields: cell survival, DNA damage, and cell cycle analysis.

    PubMed

    Stacey, M; Stickley, J; Fox, P; Statler, V; Schoenbach, K; Beebe, S J; Buescher, S

    2003-12-09

    High power, nanosecond pulsed electric field (nsPEF) effects have been focused on bacterial decontamination, but the impact on mammalian cells is now being revealed. During nsPEF applications, electrical pulses of 10, 60 or 300 ns durations were applied to cells using electric field amplitudes as high as 300 kV/cm. Because of the ultra-short pulse durations, the energy transferred to cells is negligible, and only non-thermal effects are observed. We investigated the genotoxicity of nsPEF on adherent and non-adherent cell lines including 10 human lines and one mouse cell line with different origin and growth characteristics. We present data examining the effects of nsPEF exposure on cell survival assessed by clonogenic formation or live cell count; DNA damage determined by the comet assay and chromosome aberrations; and cell cycle parameters by measuring the mitotic indices of exposed cells. Using each of these indicators, we observed differential effects among cell types with non-adherent cells being more sensitive to the genotoxic effects of nsPEF exposures than adherent cells. Non-adherent cultures showed a rapid decrease in cell viability (90%), induction of DNA damage, and a decrease in the number of cells reaching mitosis after one 60 ns pulse with an electric field intensity of 60 kV/cm. These effects were not observed in cells grown as adherent cultures, with the exception of the mouse 3T3 cell line, which showed survival characteristics similar to non-adherent cultures. These data suggest that nsPEF genotoxicity may be cell type specific, and therefore have potential applications in the selective removal of one cell type from another, for example, in diseased states.

  13. USING PROTEOMICS TO MONITOR PROTEIN EXPRESSION IN HUMAN CELLS EXPOSED TO CARCINOGENS

    EPA Science Inventory

    People are continuously exposed exogenously to varying amounts of chemicals that have been shown to have carcinogenic properties in experimental systems. It has been estimated that exposure to environmental chemical carcinogens in the environment may contribute significantly to t...

  14. USING PROTEOMICS TO MONITOR PROTEIN EXPRESSION IN HUMAN CELLS EXPOSED TO CARCINOGENS

    EPA Science Inventory

    People are continuously exposed exogenously to varying amounts of chemicals that have been shown to have carcinogenic properties in experimental systems. It has been estimated that exposure to environmental chemical carcinogens in the environment may contribute significantly to t...

  15. Abscisic acid signalling determines susceptibility of bundle sheath cells to photoinhibition in high light-exposed Arabidopsis leaves

    PubMed Central

    Gorecka, Magdalena; Alvarez-Fernandez, Ruben; Slattery, Katie; McAusland, Lorna; Davey, Phillip A.; Karpinski, Stanislaw; Lawson, Tracy; Mullineaux, Philip M.

    2014-01-01

    The rapid induction of the bundle sheath cell (BSC)-specific expression of ASCORBATE PEROXIDASE2 (APX2) in high light (HL)-exposed leaves of Arabidopsis thaliana is, in part, regulated by the hormone abscisic acid (ABA) produced by vascular parenchyma cells. In this study, we provide more details of the ABA signalling that regulates APX2 expression and consider its importance in the photosynthetic responses of BSCs and whole leaves. This was done using a combination of analyses of gene expression and chlorophyll a fluorescence of both leaves and individual BSCs and mesophyll cells. The regulation of APX2 expression occurs by the combination of the protein kinase SnRK2.6 (OST1):protein phosphatase 2C ABI2 and a Gα (GPA1)-regulated signalling pathway. The use of an ost1-1/gpa1-4 mutant established that these signalling pathways are distinct but interact to regulate APX2. In HL-exposed leaves, BSC chloroplasts were more susceptible to photoinhibition than those of mesophyll cells. The activity of the ABA-signalling network determined the degree of susceptibility of BSCs to photoinhibition by influencing non-photochemical quenching. By contrast, in HL-exposed whole leaves, ABA signalling did not have any major influence on their transcriptomes nor on their susceptibility to photoinhibition, except where guard cell responses were observed. PMID:24591719

  16. Increase in DNA damage in lymphocytes and micronucleus frequency in buccal cells in silica-exposed workers.

    PubMed

    Halder, Ajanta; De, Madhusnata

    2012-01-01

    The alkaline single cell gel electrophoresis (comet assay) was applied to study the genotoxic properties of silica in human peripheral blood lymphocytes (PBL). The study was designed to evaluate the DNA damage of lymphocytes and the end points like micronuclei from buccal smears in a group of 45 workers, occupationally exposed to silica, from small mines and stone quarries. The results were compared to 20 sex and age matched normal individuals. There was a statistically significant difference in the damage levels between the exposed group and the control groups. The types of damages (type I -type 1V) were used to measure the DNA damage. The numbers of micronuclei were higher in the silica-exposed population. The present study suggests that the silica exposure can induce lymphocyte DNA damage and produces significant variation of micronuclei in buccal smear.

  17. Human Monocyte-Derived Dendritic Cells Exposed to Microorganisms Involved in Hypersensitivity Pneumonitis Induce a Th1-Polarized Immune Response

    PubMed Central

    Pallandre, Jean-René; Borg, Christophe; Loeffert, Sophie; Gbaguidi-Haore, Houssein; Millon, Laurence

    2013-01-01

    Hypersensitivity pneumonitis (HP) is an immunoallergic disease characterized by a prominent interstitial infiltrate composed predominantly of lymphocytes secreting inflammatory cytokines. Dendritic cells (DCs) are known to play a pivotal role in the lymphocytic response. However, their cross talk with microorganisms that cause HP has yet to be elucidated. This study aimed to investigate the initial interactions between human monocyte-derived DCs (MoDCs) and four microorganisms that are different in nature (Saccharopolyspora rectivirgula [actinomycetes], Mycobacterium immunogenum [mycobacteria], and Wallemia sebi and Eurotium amstelodami [filamentous fungi]) and are involved in HP. Our objectives were to determine the cross talk between MoDCs and HP-causative agents and to determine whether the resulting immune response varied according to the microbial extract tested. The phenotypic activation of MoDCs was measured by the increased expression of costimulatory molecules and levels of cytokines in supernatants. The functional activation of MoDCs was measured by the ability of MoDCs to induce lymphocytic proliferation and differentiation in a mixed lymphocytic reaction (MLR). E. amstelodami-exposed (EA) MoDCs expressed higher percentages of costimulatory molecules than did W. sebi-exposed (WS), S. rectivirgula-exposed (SR), or M. immunogenum-exposed (MI) MoDCs (P < 0.05, Wilcoxon signed-rank test). EA-MoDCs, WS-MoDCs, SR-MoDCs, and MI-MoDCs induced CD4+ T cell proliferation and a Th1-polarized immune response. The present study provides evidence that, although differences were initially observed between MoDCs exposed to filamentous fungi and MoDCs exposed to bacteria, a Th1 response was ultimately promoted by DCs regardless of the microbial extract tested. PMID:23720369

  18. Comparison of hematological alterations and markers of B-cell activation in workers exposed to benzene, formaldehyde and trichloroethylene.

    PubMed

    Bassig, Bryan A; Zhang, Luoping; Vermeulen, Roel; Tang, Xiaojiang; Li, Guilan; Hu, Wei; Guo, Weihong; Purdue, Mark P; Yin, Songnian; Rappaport, Stephen M; Shen, Min; Ji, Zhiying; Qiu, Chuangyi; Ge, Yichen; Hosgood, H Dean; Reiss, Boris; Wu, Banghua; Xie, Yuxuan; Li, Laiyu; Yue, Fei; Freeman, Laura E Beane; Blair, Aaron; Hayes, Richard B; Huang, Hanlin; Smith, Martyn T; Rothman, Nathaniel; Lan, Qing

    2016-07-01

    Benzene, formaldehyde (FA) and trichloroethylene (TCE) are ubiquitous chemicals in workplaces and the general environment. Benzene is an established myeloid leukemogen and probable lymphomagen. FA is classified as a myeloid leukemogen but has not been associated with non-Hodgkin lymphoma (NHL), whereas TCE has been associated with NHL but not myeloid leukemia. Epidemiologic associations between FA and myeloid leukemia, and between benzene, TCE and NHL are, however, still debated. Previously, we showed that these chemicals are associated with hematotoxicity in cross-sectional studies of factory workers in China, which included extensive personal monitoring and biological sample collection. Here, we compare and contrast patterns of hematotoxicity, monosomy 7 in myeloid progenitor cells (MPCs), and B-cell activation biomarkers across these studies to further evaluate possible mechanisms of action and consistency of effects with observed hematologic cancer risks. Workers exposed to benzene or FA, but not TCE, showed declines in cell types derived from MPCs, including granulocytes and platelets. Alterations in lymphoid cell types, including B cells and CD4+ T cells, and B-cell activation markers were apparent in workers exposed to benzene or TCE. Given that alterations in myeloid and lymphoid cell types are associated with hematological malignancies, our data provide biologic insight into the epidemiological evidence linking benzene and FA exposure with myeloid leukemia risk, and TCE and benzene exposure with NHL risk. Published by Oxford University Press 2016.

  19. Micronuclei in peripheral blood and bone marrow cells of mice exposed to 42 GHz electromagnetic millimeter waves.

    PubMed

    Vijayalaxmi; Logani, Mahendra K; Bhanushali, Ashok; Ziskin, Marvin C; Prihoda, Thomas J

    2004-03-01

    The genotoxic potential of 42.2 +/- 0.2 GHz electromagnetic millimeter-wave radiation was investigated in adult male BALB/c mice. The radiation was applied to the nasal region of the mice for 30 min/day for 3 consecutive days. The incident power density used was 31.5 +/- 5.0 mW/cm2. The peak specific absorption rate was calculated as 622 +/- 100 W/kg. Groups of mice that were injected with cyclophosphamide (15 mg/kg body weight), a drug used in the treatment of human malignancies, were also included to determine if millimeter-wave radiation exposure had any influence on drug-induced genotoxicity. Concurrent sham-exposed and untreated mice were used as controls. The extent of genotoxicity was assessed from the incidence of micronuclei in polychromatic erythrocytes of peripheral blood and bone marrow cells collected 24 h after treatment. The results indicated that the incidence of micronuclei in 2000 polychromatic erythrocytes was not significantly different among untreated, millimeter wave-exposed, and sham-exposed mice. The group mean incidences were 6.0 +/- 1.6, 5.1 +/- 1.5 and 5.1 +/- 1.3 in peripheral blood and 9.1 +/- 1.1, 9.3 +/- 1.6 and 9.1 +/- 1.6 in bone marrow cells, respectively. Mice that were injected with cyclophosphamide exhibited significantly increased numbers of micronuclei, 14.6 +/- 2.7 in peripheral blood and 21.3 +/- 3.9 in bone marrow cells (P< 0.0001). The drug-induced micronuclei were not significantly different in millimeter wave-exposed and sham-exposed mice; the mean incidences were 14.3 +/- 2.8 and 15.4 +/- 3.0 in peripheral blood and 23.5 +/- 2.3 and 22.1 +/- 2.5 in bone marrow cells, respectively. Thus there was no evidence for the induction of genotoxicity in the peripheral blood and bone marrow cells of mice exposed to electromagnetic millimeter-wave radiation. Also, millimeter-wave radiation exposure did not influence cyclophosphamide-induced micronuclei in either type of cells.

  20. Acute respiratory bronchiolitis: an ultrastructural and autoradiographic study of epithelial cell injury and renewal in rhesus monkeys exposed to ozone.

    PubMed Central

    Castleman, W. L.; Dungworth, D. L.; Schwartz, L. W.; Tyler, W. S.

    1980-01-01

    The pathogenesis of acute respiratory bronchiolitis was examined in rhesus monkeys exposed to 0.8 ppm ozone fpr 4--50 hours. Epithelial injury and renewal was qualitatively and quantitatively characterized by correlated techniques of scanning and transmission electron microscopy as well as by light-microscopic autoradiography following labeling with tritiated thymidine. Extensive degeneration and necrosis of Type 1 epithelial cells occurred on the respiratory bronchiolar wall during the initial 4--12 hours of exposure. Increased numbers of labeled epithelial cells were present in this region after 18 hours of exposure, and the highest labeling index (18% was measured after 50 hours of exposure. Most (67--80%) of the labeled cells and all the mitotic epithelial cells (22) observed ultrastructurally were cuboidal bronchiolar epithelial cells. Of the labeled epithelial cells, 20--33% were Type 2 epithelial cells. After 50 hours of exposure the respiratory bronchiolar epithelium was hyperplastic. The predominant inflammatory cell in respiratory bronchiolar exudate was the alveolar macrophage. Monkeys that were exposed for 50 hours and allowed to recover in unozonized air for 7 days had incomplete resolution of respiratory bronchiolar epithelial hyperplasia. The results indicate that Type 1 epithelial cells lining respiratory bronchioles are the cell type most sensitive to injury and that both cuboidal bronchiolar epithelial cells and Type 2 epithelial cells function as stem cells in epithelial renewal. Images Figure 16 Figure 17 Figure 18 Figure 19 Figure 20 Figure 21 Figure 22 Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 23 Figure 24 Figure 25 Figure 9 Figure 10 Figure 26 Figure 27 Figure 11 Figure 12 Figure 13 Figure 14 Figure 15 PMID:6767409

  1. Controversial cytogenetic observations in mammalian somatic cells exposed to extremely low frequency electromagnetic radiation: a review and future research recommendations.

    PubMed

    Vijayalaxmi; Obe, Guenter

    2005-07-01

    During the years 1990-2003, a large number of investigations were conducted using animals, cultured rodent and human cells as well as freshly collected human blood lymphocytes to determine the genotoxic potential of exposure to nonionizing radiation emitted from extremely low frequency electromagnetic fields (EMF). Among the 63 peer reviewed scientific reports, the conclusions from 29 studies (46%) did not indicate increased damage to the genetic material, as assessed from DNA strand breaks, incidence of chromosomal aberrations (CA), micronuclei (MN), and sister chromatid exchanges (SCE), in EMF exposed cells as compared with sham exposed and/or unexposed cells, while those from 14 investigations (22%) have suggested an increase in such damage in EMF exposed cells. The observations from 20 other studies (32%) were inconclusive. This study reviews the investigations published in peer reviewed scientific journals during 1990-2003 and attempts to identify probable reason(s) for the conflicting results. Recommendations are made for future research to address some of the controversial observations.

  2. RNA-seq based gene expression analysis of ovarian granulosa cells exposed to zearalenone in vitro: significance to steroidogenesis

    PubMed Central

    Zhang, Guo-Liang; Zhang, Rui-Qian; Sun, Xiao-Feng; Cheng, Shun-Feng; Wang, Yu-Feng; Ji, Chuan-Liang; Feng, Yan-Zhong; Yu, Jie; Ge, Wei; Zhao, Yong; Sun, Shi-Duo; Shen, Wei; Li, Lan

    2017-01-01

    Zearalenone (ZEA) is a natural contaminant of various food and feed products representing a significant problem worldwide. Since the occurrence of ZEA in grains and feeds is frequent, the present study was carried out to evaluate the possible effects of ZEA on steroid production and gene expression of porcine granulosa cells, using RNA-seq analysis. Porcine granulosa cells were administered 10 μM and 30 μM ZEA during 72 h of culture in vitro. Following ZEA treatment the gene expression profile of control and exposed granulosa cells was compared using RNA-seq analysis. The results showed that in the exposed granulosa cells ZEA significantly altered the transcript levels, particularly steroidogenesis associated genes. Compared with the control group, 10 μM and 30 μM ZEA treatment significantly increased the mRNA expression of EDN1, IER3, TGFβ and BDNF genes and significantly reduced the mRNA expression of IGF-1 and SFRP2 genes. In particular, ZEA significantly decreased the expression of genes essential for estrogen synthesis including FSHR, CYP19A1 and HSD17β in granulosa cells. Furthermore, Q-PCR and Western-blot analysis also confirmed reduced expression of these genes in ZEA exposed granulosa cells. These effects were associated with a significant reduction of 17β-estradiol concentrations in the culture medium of granulosa cells. Collectively, these results demonstrated a concretely deleterious effect of ZEA exposure on the mRNA expression of steroidogenesis related genes and the production of steroid hormones in porcine ovarian granulosa cells in vitro. PMID:28969048

  3. Differential Adaptive Response and Survival of Salmonella enterica Serovar Enteritidis Planktonic and Biofilm Cells Exposed to Benzalkonium Chloride▿

    PubMed Central

    Mangalappalli-Illathu, Anil K.; Vidović, Sinisa; Korber, Darren R.

    2008-01-01

    This study examined the adaptive response and survival of planktonic and biofilm phenotypes of Salmonella enterica serovar Enteritidis adapted to benzalkonium chloride (BC). Planktonic cells and biofilms were continuously exposed to 1 μg ml−1 of BC for 144 h. The proportion of BC-adapted biofilm cells able to survive a lethal BC treatment (30 μg ml−1) was significantly higher (4.6-fold) than that of BC-adapted planktonic cells. Similarly, there were 18.3-fold more survivors among the BC-adapted biofilm cells than among their nonadapted (i.e., without prior BC exposure) cell counterparts at the lethal BC concentration, and this value was significantly higher than the value for BC-adapted planktonic cells versus nonadapted cells (3.2-fold). A significantly higher (P < 0.05) proportion of surviving cells was noticed among BC-adapted biofilm cells relative to BC-adapted planktonic cells following a 10-min heat shock at 55°C. Fatty acid composition was significantly influenced by phenotype (planktonic cells or biofilm) and BC adaptation. Cell surface roughness of biofilm cells was also significantly greater (P < 0.05) than that of planktonic cells. Key proteins upregulated in BC-adapted planktonic and biofilm cells included CspA, TrxA, Tsf, YjgF, and a probable peroxidase, STY0440. Nine and 17 unique proteins were upregulated in BC-adapted planktonic and biofilm cells, respectively. These results suggest that enhanced biofilm-specific upregulation of 17 unique proteins, along with the increased expression of CspA, TrxA, Tsf, YjgF, and a probable peroxidase, phenotype-specific alterations in cell surface roughness, and a shift in fatty acid composition conferred enhanced survival to the BC-adapted biofilm cell population relative to their BC-adapted planktonic cell counterparts. PMID:18663028

  4. Phenotypic malignant changes and untargeted lipidomic analysis of long-term exposed prostate cancer cells to endocrine disruptors

    SciTech Connect

    Bedia, Carmen Dalmau, Núria Jaumot, Joaquim Tauler, Romà

    2015-07-15

    Endocrine disruptors (EDs) are a class of environmental toxic molecules able to interfere with the normal hormone metabolism. Numerous studies involve EDs exposure to initiation and development of cancers, including prostate cancer. In this work, three different EDs (aldrin, aroclor 1254 and chlorpyrifos (CPF)) were investigated as potential inducers of a malignant phenotype in DU145 prostate cancer cells after a chronic exposure. Epithelial to mesenchymal transition (EMT) induction, proliferation, migration, colony formation and release of metalloproteinase 2 (MMP-2) were analyzed in 50-day exposed cells to the selected EDs. As a result, aldrin and CPF exposure led to an EMT induction (loss of 16% and 14% of E-cadherin levels, respectively, compared to the unexposed cells). Aroclor and CPF presented an increased migration (134% and 126%, respectively), colony formation (204% and 144%, respectively) and MMP-2 release (137% in both cases) compared to the unexposed cells. An untargeted lipidomic analysis was performed to decipher the lipids involved in the observed transformations. As general results, aldrin exposure showed a global decrease in phospholipids and sphingolipids, and aroclor and CPF showed an increase of certain phospholipids, glycosphingolipids as well as a remarkable increase of some cardiolipin species. Furthermore, the three exposures resulted in an increase of some triglyceride species. In conclusion, some significant changes in lipids were identified and thus we postulate that some lipid compounds and lipid metabolic pathways could be involved in the acquisition of the malignant phenotype in exposed prostate cancer cells to the selected EDs. - Highlights: • Aldrin, aroclor and chlorpyrifos induced an aggressive phenotype in DU145 cells. • An untargeted lipidomic analysis has been performed on chronic exposed cells. • Lipidomic results showed changes in specific lipid species under chronic exposure. • These lipids may have a role in the

  5. Evaluation of cytotoxicity, morphological alterations and oxidative stress in Chinook salmon cells exposed to copper oxide nanoparticles.

    PubMed

    Srikanth, Koigoora; Pereira, Eduarda; Duarte, Armando C; Rao, Janapala Venkateswara

    2016-05-01

    The current study is aimed to study cytotoxicity and oxidative stress mediated changes induced by copper oxide nanoparticles (CuO NPs) in Chinook salmon cells (CHSE-214). To this end, a number of biochemical responses are evaluated in CHSE-214 cells which are as follows [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide] MTT, neutral red uptake (NRU), lactate dehydrogenase (LDH), protein carbonyl (PC), lipid peroxidation (LPO), oxidised glutathione (GSSG), reduced glutathione (GSH), glutathione peroxidase (GPx), glutathione sulfo-transferase (GST), superoxide dismutase (SOD), catalase (CAT), 8-Hydroxy-2'-deoxyguanosine (8-OHdG) and reactive oxygen species (ROS), respectively. The 50% inhibition concentration (IC50) of CuO NPs to CHSE-214 cells after 24 h exposure was found to be 19.026 μg ml(-1). Viability of cells was reduced by CuO NPs, and the decrease was dose dependent as revealed by the MTT and NRU assay. CHSE-214 cells exposed to CuO NPs induced morphological changes. Initially, cells started to detach from the surface (12 h), followed by polyhedric, fusiform appearance (19 h) and finally the cells started to shrink. Later, the cells started losing their cellular contents leading to their death only after 24 h. LDH, PC, LPO, GSH, GPx, GST, SOD, CAT, 8-OHdG and ROS responses were seen significantly increased with the increase in the concentration of CuO NPs when compared to their respective controls. However, significant decrease in GSSG was perceptible in CHSE-214 cells exposed to CuO NPs in a dose-dependent manner. Our data demonstrated that CuO NPs induced cytotoxicity in CHSE-214 cells through the mediation of oxidative stress. The current study provides a baseline for the CuO NPs-mediated cytotoxic assessment in CHSE-214 cells for the future studies.

  6. LASER CAPTURE MICRODISSECTION AND GENE ARRAY ANALYSIS OF PALATAL EPITHELIAL AND MESENCHYMAL CELLS EXPOSED TO TCDD

    EPA Science Inventory

    Palatal shelves from embryos exposed on gestation day (GD) 12 to either retinoic acid (RA) or 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) contact but fail to fuse. It is of interest to know if diverse agents that induce clefting via the same etiology also activate the same biochem...

  7. LASER CAPTURE MICRODISSECTION AND GENE ARRAY ANALYSIS OF PALATAL EPITHELIAL AND MESENCHYMAL CELLS EXPOSED TO TCDD

    EPA Science Inventory

    Palatal shelves from embryos exposed on gestation day (GD) 12 to either retinoic acid (RA) or 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) contact but fail to fuse. It is of interest to know if diverse agents that induce clefting via the same etiology also activate the same biochem...

  8. Cell viability, reactive oxygen species, apoptosis, and necrosis in myoblast cultures exposed to low-level infrared laser.

    PubMed

    Alexsandra da Silva Neto Trajano, Larissa; da Silva, Camila Luna; de Carvalho, Simone Nunes; Cortez, Erika; Mencalha, André Luiz; de Souza da Fonseca, Adenilson; Stumbo, Ana Carolina

    2016-07-01

    Low-level infrared laser is considered safe and effective for treatment of muscle injuries. However, the mechanism involved on beneficial effects of laser therapy are not understood. The aim was to evaluate cell viability, reactive oxygen species, apoptosis, and necrosis in myoblast cultures exposed to low-level infrared laser at therapeutic fluences. C2C12 myoblast cultures at different (2 and 10 %) fetal bovine serum (FBS) concentrations were exposed to low-level infrared laser (808 nm, 100 mW) at different fluences (10, 35, and 70 J/cm(2)) and evaluated after 24, 48, and 72 h. Cell viability was evaluated by WST-1 assay; reactive oxygen species (ROS), apoptosis, and necrosis were evaluated by flow cytometry. Cell viability was decreased atthe lowest FBS concentration. Laser exposure increased the cell viability in myoblast cultures at 2 % FBS after 48 and 72 h, but no significant increase in ROS was observed. Apoptosis was decreased at the higher fluence and necrosis was increased at lower fluence in myoblast cultures after 24 h of laser exposure at 2 % FBS. No laser-induced alterations were obtained at 10 % FBS. Results show that level of reactive oxygen species is not altered, at least to those evaluated in this study, but low-level infrared laser exposure affects cell viability, apoptosis, and necrosis in myoblast cultures depending on laser fluence and physiologic conditions of cells.

  9. Mutagenic adaptive response to high-LET radiation in human lymphoblastoid cells exposed to X-rays.

    PubMed

    Varès, Guillaume; Wang, Bing; Tanaka, Kaoru; Kakimoto, Ayana; Eguchi-Kasai, Kyomi; Nenoi, Mitsuru

    2011-01-10

    The ability of cells to adapt low-dose or low-dose rate radiation is well known. High-LET radiation has unique characteristics, and the data concerning low doses effects and high-LET radiation remain fragmented. In this study, we assessed in vitro the ability of low doses of X-rays to induce an adaptive response (AR) to a subsequent challenging dose of heavy-ion radiation. Lymphoblastoid cells (TK6, AHH-1, NH32) were exposed to priming 0.02-0.1Gy X-rays, followed 6h later by challenging 1Gy heavy-ion radiation (carbon-ion: 20 and 40keV/μm, neon-ion: 150keV/μm). Pre-exposure of p53-competent cells resulted in decreased mutation frequencies at hypoxanthine-guanine phosphoribosyl transferase locus and different H2AX phosphorylation kinetics, as compared to cells exposed to challenging radiation alone. This phenomenon did not seem to be linked with cell cycle effects or radiation-induced apoptosis. Taken together, our results suggested the existence of an AR to mutagenic effects of heavy-ion radiation in lymphoblastoid cells and the involvement of double-strand break repair mechanisms.

  10. SOX9 Regulates Cancer Stem-Like Properties and Metastatic Potential of Single-Walled Carbon Nanotube-Exposed Cells.

    PubMed

    Voronkova, Maria A; Luanpitpong, Sudjit; Rojanasakul, Liying Wang; Castranova, Vincent; Dinu, Cerasela Zoica; Riedel, Heimo; Rojanasakul, Yon

    2017-09-14

    Engineered nanomaterials hold great promise for the future development of innovative products but their adverse health effects are a major concern. Recent studies have indicated that certain nanomaterials, including carbon nanotubes (CNTs), may be carcinogenic. However, the underlying mechanisms behind their potential malignant properties remain unclear. In this study, we linked SOX9, a stem cell associated transcription factor, to the neoplastic-like properties of human lung epithelial cells chronically exposed to a low-dose of single-walled carbon nanotubes (SWCNTs). We found that SOX9 is upregulated in SWCNT-exposed cells, which is consistent with their abilities to induce tumor formation and metastasis in vivo. We therefore hypothesized that SOX9 overexpression may be responsible for the neoplastic-like phenotype observed in our model. Indeed, SOX9 knockdown inhibited anchorage-independent cell growth in vitro and lung colonization in vivo in a mouse xenograft model. SOX9 depletion also suppressed the formation of cancer stem-like cells (CSCs), as determined by tumor sphere formation and aldehyde dehydrogenase (ALDH) activity (Aldefluor) assays. Furthermore, SOX9 knockdown suppressed tumor metastasis and the expression of the stem cell marker ALDH1A1. Taken together, our findings provide a mechanistic insight into SWCNT-induced carcinogenesis and the role of SOX9 in CSC regulation and metastasis.

  11. Global Transcriptomic Analysis of Model Human Cell Lines Exposed to Surface-Modified Gold Nanoparticles: The Effect of Surface Chemistry

    PubMed Central

    Grzincic, E. M.; Yang, J. A.; Drnevich, J.; Falagan-Lotsch, P.; Murphy, C. J.

    2015-01-01

    Gold nanoparticles (Au NPs) are attractive for biomedical applications not only for their remarkable physical properties, but also for the ease of which their surface chemistry can be manipulated. Many applications involve functionalization of the Au NP surface in order to improve biocompatibility, attach targeting ligands or carry drugs. However, changes in cells exposed to Au NPs of different surface chemistries have been observed, and little is known about how Au NPs and their surface coatings may impact cellular gene expression. The gene expression of two model human cell lines, human dermal fibroblasts (HDF) and prostate cancer cells (PC3) was interrogated by microarray analysis of over 14,000 human genes. The cell lines were exposed to four differently functionalized Au NPs: citrate, poly(allylamine hydrochloride) (PAH), and lipid coatings combined with alkanethiols or PAH. Gene functional annotation categories and weighted gene correlation network analysis were used in order to connect gene expression changes to common cellular functions and to elucidate expression patterns between Au NP samples. Coated Au NPs affect genes implicated in proliferation, angiogenesis, and metabolism in HDF cells, and inflammation, angiogenesis, proliferation apoptosis regulation, survival and invasion in PC3 cells. Subtle changes in surface chemistry, such as the initial net charge, lability of the ligand, and underlying layers greatly influence the degree of expression change and the type of cellular pathway affected. PMID:25491924

  12. Early alterations on photosynthesis-related parameters in Chlamydomonas reinhardtii cells exposed to atrazine: A multiple approach study.

    PubMed

    Esperanza, Marta; Seoane, Marta; Rioboo, Carmen; Herrero, Concepción; Cid, Ángeles

    2016-06-01

    Chlamydomonas reinhardtii cells were exposed to a sublethal concentration of the widespread herbicide atrazine for 3h. Physiological cellular parameters, such as chlorophyll a fluorescence and oxidative stress monitored by flow cytometry and pigments levels were altered in microalgal cells exposed to 0.25 μM of atrazine. Furthermore, the effects of this herbicide on C. reinhardtii were explored using "omics" techniques. Transcriptomic analyses, carried out by RNA-Seq technique, displayed 9 differentially expressed genes, related to photosynthesis, between control cultures and atrazine exposed cultures. Proteomic profiles were obtained using iTRAQ tags and MALDI-MS/MS analysis, identifying important changes in the proteome during atrazine stress; 5 proteins related to photosynthesis were downexpressed. The results of these experiments advance the understanding of photosynthetic adjustments that occur during an early herbicide exposure. Inhibition of photosynthesis induced by atrazine toxicity will affect the entire physiological and biochemical states of microalgal cells. Copyright © 2016. Published by Elsevier B.V.

  13. Evaluation of DNA damage in agricultural workers exposed to pesticides using single cell gel electrophoresis (comet) assay.

    PubMed

    Kaur, Raminderjeet; Kaur, Satbir; Lata, Mukesh

    2011-09-01

    Pesticides are used in agriculture to protect crops, but they pose a potential risk to farmers and environment. The aim of the present study is to investigate the relation between the occupational exposure to various pesticides and the presence of DNA damage. Blood samples of 210 exposed workers (after a day of intense spraying) and 50 control subjects belonging to various districts of Punjab (India) were evaluated using Comet assay. Sixty workers who showed DNA damage were selected for follow up at 5-6 months after the first sampling during a low or null spraying period. Significant differences were found in DNA damage between freshly exposed workers and controls and freshly exposed and followed up cases. There was significant increase in the comet parameters viz. mean comet tail length and frequency of cells showing migration in exposed workers as compared to controls (72.22 ± 20.76 vs. 46.92 ± 8.17, P<0.001; 31.79 vs. 5.77, P<0.001). In the second samples, followed up cases showed significant decrease in frequency of damaged cells as compared to freshly exposed workers of first sampling (P<0.05). The confounding factors such as variable duration of pesticide exposure, age, smoking, drinking and dietary habits etc which were expected to modulate the damage, were instead found to have no significant effect on DNA fragmentation. The evidence of a genetic hazard related to exposure resulting from the intensive use of pesticides stresses the need for educational programs for agricultural workers to reduce the use of chemicals in agriculture.

  14. Interleukins 2 and 12 produce significant recovery of cytotoxic function in dibutyltin-exposed human natural killer cells.

    PubMed

    Whalen, Margaret M; Walker, Latarchal; Loganathan, Bommanna G

    2002-02-01

    Cytotoxic function of human natural killer (NK) cells is modulated by a variety of cytokines. Interleukins (IL) 2, 12, 15, and 18 and Interferon gamma (IFNgamma) are potent stimulators of NK cell cytotoxicity. Butyltins (BTs) are used in a variety of consumer products and industrial applications. Dibutyltin (DBT) is found in plastic products, beverages stored in PVC pipes during manufacturing, and poultry products. BTs appear to increase the risk of cancer and viral infections in exposed individuals. Recently, we have demonstrated that the ability of NK cells to kill tumor cells is greatly diminished after a 1-h exposure to dibutyltin. This inhibition of tumor killing function continues even after removal of the compound. There is no significant recovery of NK cytotoxic function even when the cells are allowed to recover for 6 days. In the current study we examine the effects of NK-stimulatory cytokines on the ability of NK cells to recover from the inhibitory effects of a 1-h DBT treatment. Highly purified NK cells (>95% CD16(+)) or a lymphocyte preparation containing both T lymphocytes and NK cells were treated with 5 microM DBT and then allowed to recover for 24 h, 48 h, 4 days, and 6 days in DBT-free medium containing either no cytokine or a maximally stimulatory dose of several NK-stimulatory cytokines. Tumor killing function was tested using a radioactive chromium release assay. As seen in our previous studies there is no recovery of NK cell cytotoxic function even after a 6-day recovery period when no cytokine is present in the medium. However, there is significant recovery of NK cytotoxic function when IL2, IL12, or the combination of IL2 plus IL12 is present in the medium during the recovery period. The other cytokines tested (IL15, IL18, and IFNgamma) were unable to increase the cytotoxicity of DBT-exposed NK cells.

  15. Signs of Müller cell gliotic response found in the retina of newts exposed to real and simulated microgravity

    NASA Astrophysics Data System (ADS)

    Grigoryan, E. N.; Anton, H. J.; Poplinskaya, V. A.; Aleinikova, K. S.; Domaratskaya, E. I.; Novikova, Y. P.; Almeida, E.

    2012-05-01

    The effects of real and simulated microgravity on the eye tissue regeneration of newts were investigated. For the first time changes in Müller glial cells in the retina of eyes regenerating after retinal detachment were detected in newts exposed to clinorotation. The cells divided, were hypertrophied, and their processes were thickened. Such changes suggested reactive gliosis and were more significant in animals exposed to rotation when compared with desk-top controls. Later experiments onboard the Russian biosatellite Bion-11 showed similar changes in the retinas that were regenerating in a two-week spaceflight. In the Bion-11 animals, GFAP, the major structural protein of retinal macroglial cells, was found to be upregulated. In a more recent experiment onboard Foton-M3 (2007), GFAP expression in retinas of space-flown, ground control (kept at 1 g), and basal control (sacrificed on launch day) newts was quantified, using microscopy, immunohistochemistry, and digital image analysis. A low level of immunoreactivity was observed in basal controls. In contrast, retinas of space-flown animals showed greater GFAP immunoreactivity associated with both an increased cell number and a higher thickness of intermediate filaments. This, in turn, was accompanied by up-regulation of stress protein (HSP90) and growth factor (FGF2) expressions. It can be postulated that such a response of Müller cells was to mitigate the retinal stress in newts exposed to microgravity. Taken together, the data suggest that the retinal population of macroglial cells could be sensitive to gravity changes and that in space it can react by enhancing its neuroprotective function.

  16. Gene Expression Changes in Human Lung Cells Exposed to Arsenic, Chromium, Nickel or Vanadium Indicate the First Steps in Cancer

    PubMed Central

    Clancy, Hailey A.; Sun, Hong; Passantino, Lisa; Kluz, Thomas; Muñoz, Alexandra; Zavadil, Jiri; Costa, Max

    2013-01-01

    The complex process of carcinogenesis begins with transformation of a single cell to favor aberrant traits such as loss of contact inhibition and unregulated proliferation – features found in every cancer. Despite cancer’s widespread prevalence, the early events that initiate cancer remain elusive, and without knowledge of these events cancer prevention is difficult. Here we show that exposure to As, Cr, Ni, or Vanadium (V) promotes changes in gene expression that occur in conjunction with aberrant growth. We exposed immortalized human bronchial epithelial cells to one of four metals/metalloid for four to eight weeks and selected transformed clonal populations based upon anchorage independent growth of single cells in soft agar. We detected a metal-specific footprint of cancer-related gene expression that was consistent across multiple transformed clones. These gene expression changes persisted in the absence of the progenitor metal for numerous cell divisions. Our results show that even a brief exposure to a carcinogenic metal may cause many changes in gene expression in the exposed cells, and that from these many changes, the specific change(s) that each metal causes that initiate cancer likely arise. PMID:22714537

  17. NF-κB signaling maintains the survival of cadmium-exposed human renal glomerular endothelial cells.

    PubMed

    Zhang, Hongyan; Li, Liqun; Wang, Yifan; Dong, Fengyun; Chen, Xiaocui; Liu, Fuhong; Xu, Dongmei; Yi, Fan; Kapron, Carolyn M; Liu, Ju

    2016-08-01

    The kidney is one of the primary organs targeted by cadmium (Cd), a widely distributed environmental pollutant. The glomerular endothelium is the major component of the glomerular filtration barrier. However, the effects of Cd on glomerular endothelial cells remain largely unknown. For this purpose, we aimed to determine the effects of low dose Cd on the survival of human renal glomerular endothelial cells (HRGECs). Cultured HRGECs were exposed to 4 µM cadmium chloride (CdCl2) and examined at different time-points. We found that Cd activates the nuclear factor-κB (NF-κB) pathway without inducing the apoptosis of HRGECs. Pre-treating the cells with pyrrolidine dithiocarbamate (PDTC), a potent NF-κB inhibitor, prior to Cd exposure triggered extensive cell death (73.5%). In addition, Cd activates the c-Jun N-terminal kinase (JNK) pathway, and inhibition of the NF-κB pathway significantly elevates Cd-induced JNK phosphorylation in HRGECs (p<0.01). The combination treatment of PDTC and SP600125, a JNK pathway inhibitor, increased the survival of Cd-stimulated HRGECs compared with those cells treated with PDTC alone (p<0.05). Taken together, these findings demonstrate that the NF-κB pathway plays an essential role in maintaining the survival of Cd-exposed HRGECs.

  18. Increased Frequency of Spontaneous Neoplastic Transformation in Progeny of Bystander Cells from Cultures Exposed to Densely Ionizing Radiation

    PubMed Central

    Buonanno, Manuela; de Toledo, Sonia M.; Azzam, Edouard I.

    2011-01-01

    An increased risk of carcinogenesis caused by exposure to space radiation during prolonged space travel is a limiting factor for human space exploration. Typically, astronauts are exposed to low fluences of ionizing particles that target only a few cells in a tissue at any one time. The propagation of stressful effects from irradiated to neighboring bystander cells and their transmission to progeny cells would be of importance in estimates of the health risks of exposure to space radiation. With relevance to the risk of carcinogenesis, we investigated, in model C3H 10T½ mouse embryo fibroblasts (MEFs), modulation of the spontaneous frequency of neoplastic transformation in the progeny of bystander MEFs that had been in co-culture 10 population doublings earlier with MEFs exposed to moderate doses of densely ionizing iron ions (1 GeV/nucleon) or sparsely ionizing protons (1 GeV). An increase (P<0.05) in neoplastic transformation frequency, likely mediated by intercellular communication through gap junctions, was observed in the progeny of bystander cells that had been in co-culture with cells irradiated with iron ions, but not with protons. PMID:21738697

  19. Adaptive response in mouse bone marrow stromal cells exposed to 900MHz radiofrequency fields: Impact of poly (ADP-ribose) polymerase (PARP).

    PubMed

    He, Qina; Zong, Lin; Sun, Yulong; Vijayalaxmi; Prihoda, Thomas J; Tong, Jian; Cao, Yi

    2017-08-01

    This study examined whether non-ionizing radiofrequency fields (RF) exposure is capable of inducing poly (ADP-ribose) polymerase-1 (PARP-1) in bone marrow stromal cells (BMSCs) and whether it plays a role in RF-induced adaptive response (AR). Bone marrow stromal cells (BMSCs) were exposed to 900MHz RF at 120μW/cm(2) power flux density for 3h/day for 5days and then challenged with a genotoxic dose of 1.5Gy gamma-radiation (GR). Some cells were also treated with 3-aminobenzamide (3-AB, 2mM final concentration), a potent inhibitor of PARP-1. Un-exposed and sham (SH)-exposed control cells as well as positive control cells exposed to gamma radiation (GR) were included in the experiments. The expression of PARP-1 mRNA and its protein levels as well as single strand breaks in the DNA and the kinetics of their repair were evaluated at several times after exposures. The results indicated the following. (a) Cells exposed to RF alone showed significantly increased PARP-1 mRNA expression and its protein levels compared with those exposed to SH- and GR alone. (b) Treatment of RF-exposed cells with 3-AB had diminished such increase in PARP-1. (c) Cells exposed to RF+GR showed significantly decreased genetic damage as well as faster kinetics of repair compared with those exposed to GR alone. (d) Cells exposed to RF+3-AB+GR showed no such decrease in genetic damage. Thus, the overall date suggested that non-ionizing RF exposure was capable of inducing PARP-1 which has a role in RF-induced AR. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Synergistic cytotoxicity and DNA strand breaks in cells and plasmid DNA exposed to uranyl acetate and ultraviolet radiation

    PubMed Central

    Wilson, Janice; Zuniga, Mary C.; Yazzie, Filbert; Stearns, Diane M.

    2015-01-01

    Depleted uranium (DU) has a chemical toxicity that is independent of its radioactivity. The purpose of this study was to explore the photoactivation of uranyl ion by ultraviolet (UV) radiation as a chemical mechanism of uranium genotoxicity. The ability of UVB (302 nm) and UVA (368 nm) radiation to photoactivate uranyl ion to produce single strand breaks was measured in pBR322 plasmid DNA, and the presence of adducts and apurinic/apyrimidinic sites that could be converted to single strand breaks by heat and piperidine was analyzed. Results showed that DNA lesions in plasmid DNA exposed to UVB- or UVA-activated DU were only slightly heat reactive, but were piperidine sensitive. The cytotoxicity of UVB-activated uranyl ion was measured in repair-proficient and repair-deficient Chinese hamster ovary cells and human keratinocyte HaCaT cells. The cytotoxicity of co-exposures of uranyl ion and UVB radiation was dependent on the order of exposure and was greater than co-exposures of arsenite and UVB radiation. Uranyl ion and UVB radiation were synergistically cytotoxic in cells, and cells exposed to photoactivated DU required different DNA repair pathways than cells exposed to non-photoactivated DU. This study contributes to our understanding of the DNA lesions formed by DU, as well as their repair. Results suggest that excitation of uranyl ion by UV radiation can provide a pathway for uranyl ion to be chemically genotoxic in populations with dermal exposures to uranium and UV radiation, which would make skin an overlooked target organ for uranium exposures. PMID:24832689

  1. Mitochondrial-mediated apoptosis pathway in alveolar epithelial cells exposed to the metals in combustion-generated particulate matter.

    PubMed

    Visalli, Giuseppa; Baluce, Barbara; Bertuccio, Maria; Picerno, Isa; Di Pietro, Angela

    2015-01-01

    Previously a significant mitochondrial impairment was identified in alveolar epithelial cells exposed to metals adsorbed to combustion-generated particulate matter (PM). Due to the critical role of mitochondria in apoptosis, the aim of this study was to investigate the pro-apoptotic potential of metals present in oil fly ash (OFA). A549 cells were exposed to water-soluble components of an OFA sample, containing vanadium [V(IV)], iron [Fe(III)], and nickel [Ni(II)] (68.8, 110.4, and 18 μM, respectively). Experiments were also performed using individual metal solutions. Apoptosis was detected and the mitochondrial role was assessed by a caspase-9 inhibitor (Z-LEHD-FMK). To determine whether the presence of impaired mitochondria in unexposed daughter cells increased apoptosis, an in vitro model was developed that allowed determination of effects until the third cell generation. To specifically examine the toxicity of vanadium (V), that characterize the airborne pollutant examined in this study, p53involvement and metabolic impairment through changes in HIF-1α and Glut-1 expression were determined. OFA and individual metal solutions produced significant apoptosis in the progeny of exposed cells, triggering the intrinsic apoptosis pathway. In apoptosis induced by poorly genotoxic metal V, p53 did not play a significant role. However, V exposure increased nuclear translocation of HIF-1α and expression of the Glut-1 receptor, indicating metabolic impairment due to metal-induced mitochondrial dysfunction. Overall, these results improve our knowledge of the pathogenic role that airborne metals and in particular V exerted in respiratory epithelium.

  2. Synergistic cytotoxicity and DNA strand breaks in cells and plasmid DNA exposed to uranyl acetate and ultraviolet radiation.

    PubMed

    Wilson, Janice; Zuniga, Mary C; Yazzie, Filbert; Stearns, Diane M

    2015-04-01

    Depleted uranium (DU) has a chemical toxicity that is independent of its radioactivity. The purpose of this study was to explore the photoactivation of uranyl ion by ultraviolet (UV) radiation as a chemical mechanism of uranium genotoxicity. The ability of UVB (302 nm) and UVA (368 nm) radiation to photoactivate uranyl ion to produce single strand breaks was measured in pBR322 plasmid DNA, and the presence of adducts and apurinic/apyrimidinic sites that could be converted to single strand breaks by heat and piperidine was analyzed. Results showed that DNA lesions in plasmid DNA exposed to UVB- or UVA-activated DU were only slightly heat reactive, but were piperidine sensitive. The cytotoxicity of UVB-activated uranyl ion was measured in repair-proficient and repair-deficient Chinese hamster ovary cells and human keratinocyte HaCaT cells. The cytotoxicity of co-exposures of uranyl ion and UVB radiation was dependent on the order of exposure and was greater than co-exposures of arsenite and UVB radiation. Uranyl ion and UVB radiation were synergistically cytotoxic in cells, and cells exposed to photoactivated DU required different DNA repair pathways than cells exposed to non-photoactivated DU. This study contributes to our understanding of the DNA lesions formed by DU, as well as their repair. Results suggest that excitation of uranyl ion by UV radiation can provide a pathway for uranyl ion to be chemically genotoxic in populations with dermal exposures to uranium and UV radiation, which would make skin an overlooked target organ for uranium exposures.

  3. Pulmonary function and symptoms of Nigerian workers exposed to carbon black in dry cell battery and tire factories

    SciTech Connect

    Oleru, U.G.; Elegbeleye, O.O.; Enu, C.C.; Olumide, Y.M.

    1983-02-01

    The pulmonary function and symptoms of 125 workers exposed to carbon black in dry cell battery and tire manufacturing plants were investigated. There was no significant difference in the pulmonary function of the subjects in the two plants. There was good agreement in the symptoms reported in the two different factories: cough with phlegm production, tiredness, chest pain, catarrh, headache, and skin irritation. The symptoms also corroborate those reported in the few studies on the pulmonary effects of carbon black. The suspended particulate levels in the dry cell battery plant ranged from 25 to 34 mg/m/sup 3/ and the subjects with the highest probable exposure level had the most impaired pulmonary function. The pulmonary function of the exposed subjects was significantly lower than that of a control, nonindustrially exposed population. The drop in the lung function from the expected value per year of age was relatively constant for all the study subgroups but the drop per year of duration of employment was more severe in the earlier years of employment. This study has underscored the need for occupational health regulations in the industries of developing countries.

  4. Pulmonary function and symptoms of Nigerian workers exposed to Carbon black in dry cell battery and tire factories.

    PubMed

    Oleru, U G; Elegbeleye, O O; Enu, C C; Olumide, Y M

    1983-02-01

    The pulmonary function and symptoms of 125 workers exposed to carbon black in dry cell battery and tire manufacturing plants were investigated. There was no significant difference in the pulmonary function of the subjects in the two plants. There was good agreement in the symptoms reported in the two different factories: cough with phlegm production, tiredness, chest pain, catarrh, headache, and skin irritation. The symptoms also corroborate those reported in the few studies on the pulmonary effects of carbon black. The suspended particulate levels in the dry cell battery plant ranged from 25 to 34 mg/m3 and the subjects with the highest probable exposure level had the most impaired pulmonary function. The pulmonary function of the exposed subjects was significantly lower than that of a control, nonindustrially exposed population. The drop in the lung function from the expected value per year of age was relatively constant for all the study subgroups but the drop per year of duration of employment was more severe in the earlier years of employment. This study has underscored the need for occupational health regulations in the industries of developing countries.

  5. Differential gene expression in human hepatocyte cell lines exposed to the antiretroviral agent zidovudine.

    PubMed

    Fang, Jia-Long; Han, Tao; Wu, Qiangen; Beland, Frederick A; Chang, Ching-Wei; Guo, Lei; Fuscoe, James C

    2014-03-01

    Zidovudine (3'-azido-3'-deoxythymidine; AZT) is the most widely used nucleoside reverse transcriptase inhibitor for the treatment of AIDS patients and prevention of mother-to-child transmission of HIV-1. Previously, we demonstrated that AZT had significantly greater growth inhibitory effects upon the human liver carcinoma cell line HepG2 as compared to the immortalized human liver cell line THLE2. We have now used gene expression profiling to determine the molecular pathways associated with toxicity in both cell lines. HepG2 cells were incubated with 0, 2, 20, or 100 μM AZT for 2 weeks; THLE2 cells were treated with 0, 50, 500, or 2,500 μM AZT, concentrations that were equi-toxic to those used in the HepG2 cells. After the treatment, total RNA was isolated and subjected to microarray analysis. Global analysis of gene expression, with a false discovery rate ≤0.01 and a fold change ≥1.5, indicated that 6- to 70-fold more genes were differentially expressed in a significant concentration-dependent manner in HepG2 cells when compared to THLE2 cells. Comparative analysis indicated that 7 % of these genes were common to both cell lines. Among the common differentially expressed genes, 70 % changed in the same direction, most of which were associated with cell death and survival, cell cycle, cell growth and proliferation, and DNA replication, recombination, and repair. As determined by the uptake of [methyl-(3)H]AZT, the intracellular levels of total AZT were approximately twofold higher in THLE2 cells than in HepG2 cells. The expression of thymidine kinase 1 (TK1) and UDP-glucuronosyltransferase 2B7 (UGT2B7) genes that regulate the metabolic activation and deactivation of AZT, respectively, was increased in HepG2 cells but decreased in THLE2 cells after treatment with AZT. This differential response in AZT metabolism was confirmed by real-time PCR, western blotting, and/or enzymatic assays. These data indicate that molecular pathways involved with cell death and

  6. Oxidative stress and apoptosis induction in human thyroid carcinoma cells exposed to the essential oil from Pistacia lentiscus aerial parts

    PubMed Central

    Catalani, Simona; Palma, Francesco; Battistelli, Serafina; Benedetti, Serena

    2017-01-01

    Background Essential oils from the aerial parts (leaves, twigs and berries) of Pistacia lentiscus (PLEO) have been well characterized for their antibacterial and anti-inflammatory properties; however, poor information exists on their potential anticancer activity. Methods Increasing concentrations of PLEO (0.01–0.1% v/v, 80–800 μg/ml) were administered to a wide variety of cultured cancer cells from breast, cervix, colon, liver, lung, prostate, and thyroid carcinomas. Fibroblasts were also included as healthy control cells. Cell viability was monitored by WST-8 assay up to 72 hours after PLEO administration. The intracellular formation of reactive oxygen species (ROS), the induction of apoptosis, and the enhancement of chemotherapeutic drug cytotoxicity by PLEO were further investigated in the most responsive cancer cell line. Results A dose-dependent reduction of tumor cell viability was observed upon PLEO exposure; while no cytotoxic effect was revealed in healthy fibroblasts. FTC-133 thyroid cancer cells were found to be the most sensitive cells to PLEO treatment; accordingly, an intracellular accumulation of ROS and an activation of both the extrinsic and intrinsic apoptotic pathways were evidenced in FTC-133 cells after PLEO administration. Furthermore, the cytotoxic effect of the antineoplastic drugs cisplatin, 5-fluorouracil and etoposide was enhanced in PLEO-exposed FTC-133 cells. Conclusion Taking into account its mode of action, PLEO might be considered as a promising source of natural antitumor agents which might have therapeutic potential in integrated oncology. PMID:28196126

  7. Immunostimulatory Activity of the Cytokine-Based Biologic, IRX-2, on Human Papillomavirus-Exposed Langerhans Cells

    PubMed Central

    Da Silva, Diane M.; Woodham, Andrew W.; Naylor, Paul H.; Egan, James E.; Berinstein, Neil L.

    2016-01-01

    Langerhans cells (LCs) are the antigen-presenting cells of the epithelial layer and are responsible for initiating immune responses against skin and mucosa-invading viruses. Human papillomavirus (HPV)-mediated suppression of LC function is a crucial mechanism of HPV immune evasion, which can lead to persistent infection and development of several human cancers, including cervical, anal, and head and neck cancers. The cell-derived cytokine-based biologic, IRX-2, consists of multiple well-defined cytokines and is broadly active on various immune cell subsets. In this study, we investigated primary human LC activation after exposure to HPV16, followed by treatment with IRX-2 in vitro, and evaluated their subsequent ability to induce HPV16-specific T cells. In contrast to its activity on dendritic cells, HPV16 alone is not sufficient to induce phenotypic and functional activation of LCs. However, IRX-2 induces a significant upregulation of antigen presentation and costimulatory molecules, T helper 1 (Th1)-associated cytokine release, and chemokine-directed migration of LCs pre-exposed to HPV16. Furthermore, LCs treated with IRX-2 after HPV16 exposure induced CD8+ T-cell responses against specific HLA-A*0201-binding HPV16 T-cell epitopes. The present study suggests that IRX-2 is an attractive immunomodulator for assisting the immune response in eradication of HPV-infected cells, thereby potentially preventing HPV-induced cancers. PMID:26653678

  8. Oxidative stress and apoptosis induction in human thyroid carcinoma cells exposed to the essential oil from Pistacia lentiscus aerial parts.

    PubMed

    Catalani, Simona; Palma, Francesco; Battistelli, Serafina; Benedetti, Serena

    2017-01-01

    Essential oils from the aerial parts (leaves, twigs and berries) of Pistacia lentiscus (PLEO) have been well characterized for their antibacterial and anti-inflammatory properties; however, poor information exists on their potential anticancer activity. Increasing concentrations of PLEO (0.01-0.1% v/v, 80-800 μg/ml) were administered to a wide variety of cultured cancer cells from breast, cervix, colon, liver, lung, prostate, and thyroid carcinomas. Fibroblasts were also included as healthy control cells. Cell viability was monitored by WST-8 assay up to 72 hours after PLEO administration. The intracellular formation of reactive oxygen species (ROS), the induction of apoptosis, and the enhancement of chemotherapeutic drug cytotoxicity by PLEO were further investigated in the most responsive cancer cell line. A dose-dependent reduction of tumor cell viability was observed upon PLEO exposure; while no cytotoxic effect was revealed in healthy fibroblasts. FTC-133 thyroid cancer cells were found to be the most sensitive cells to PLEO treatment; accordingly, an intracellular accumulation of ROS and an activation of both the extrinsic and intrinsic apoptotic pathways were evidenced in FTC-133 cells after PLEO administration. Furthermore, the cytotoxic effect of the antineoplastic drugs cisplatin, 5-fluorouracil and etoposide was enhanced in PLEO-exposed FTC-133 cells. Taking into account its mode of action, PLEO might be considered as a promising source of natural antitumor agents which might have therapeutic potential in integrated oncology.

  9. Aven and Bcl-xL enhance protection against apoptosis for mammalian cells exposed to various culture conditions.

    PubMed

    Figueroa, Bruno; Chen, Sulin; Oyler, George A; Hardwick, J Marie; Betenbaugh, Michael J

    2004-03-20

    A balance between proliferation and cell death is critical for achieving desirable high cell densities in mammalian cell culture. In this study, we evaluate a recently discovered anti-apoptotic gene, aven, and examine its effectiveness alone and in combination with a member of the Bcl-2 family, bcl-xL. The commercially popular cell line, Chinese hamster ovary (CHO), was genetically modified to constitutively express aven, bcl-xL, and the two genes in combination. Cells were exposed to several model insults that simulate severe bioreactor environments, including serum deprivation, spent medium, and Sindbis virus infection, as well as staurosporine, a known chemical inducer of apoptosis. CHO cells exhibited DNA fragmentation, a hallmark of apoptosis, after exposure to these model insults. After exposure to serum deprivation, 4- and 5-day spent medium, and staurosporine, cells expressing Aven provided limited protection against cell death when compared with the protection afforded by cells expressing Bcl-xL alone. However, the highest survival levels for all insults were achieved when Aven was expressed in combination with Bcl-xL. In fact, Aven appeared to act synergistically to enhance the protective function of Bcl-xL for several insults, because the protective function of the two genes expressed together in one cell line often exceeded the additive protective levels of each anti-apoptosis gene expressed alone. Surprisingly, Aven expression provided a mildly pro-apoptotic response in CHO isolates infected with Sindbis virus. However, CHO cells expressing both Bcl-xL and Aven showed protection against Sindbis virus infection due to the inhibitory properties of the bcl-xL anti-apoptosis gene. This study shows that combinatorial anti-apoptosis cell engineering strategies may be the most effective mechanisms for providing extended protection against cell death in mammalian cell culture. Copyright 2004 Wiley Periodicals, Inc.

  10. Modulation by Ethanol of Cigarette Smoke Clastogenicity in Cells of Adult Mice and of Transplacentally Exposed Fetuses

    PubMed Central

    Balansky, Roumen; La Maestra, Sebastiano; Micale, Rosanna T.; Iltcheva, Marietta; Kirov, Krassimir; De Flora, Silvio

    2016-01-01

    Cigarette smoke (CS) and ethanol (EtOH) are known to synergize in the causation of cancers of the upper aerodigestive tract and of the liver. Little is known about possible interactions between these agents in other organs. These premises prompted us to evaluate the clastogenic effects resulting from the inhalation for 3 weeks of mainstream CS and oral administration of EtOH, which were tested either individually or in combination in cells of adult BDF1 mice and their fetuses. CS exerted clastogenic effects in haematopoietic cells of adult male mice by increasing the frequency of micronucleated erythroid cells both in bone marrow and in peripheral blood as well as the frequency of micronucleated and polynucleated pulmonary alveolar macrophages. Likewise, exposure to CS of pregnant mice resulted in a clastogenic damage in maternal bone marrow cells and in the liver and peripheral blood of their fetuses. Under all experimental conditions, EtOH was consistently devoid of clastogenic effects when given alone. In adult mice, EtOH exhibited a mild stimulating effect on the clastogenicity of CS in haematopoietic cells, while an opposite effect was observed in the respiratory tract, where EtOH attenuated the cytogenetic alterations induced by CS in pulmonary alveolar macrophages. At variance with the mild synergism observed in haematopoietic cells of adult mice, EtOH inhibited the clastogenicity of CS in the liver and peripheral blood cells of transplacentally exposed fetuses. Therefore, the effects of EtOH in CS-exposed mice show different trends depending both on the life stage and on the cells analyzed. PMID:27907070

  11. DNA lesion and Hprt mutant frequency in rat lymphocytes and V79 Chinese hamster lung cells exposed to cadmium.

    PubMed

    Jianhua, Zhou; Lian, Xue; Shuanlai, Zheng; Juan, Du; Shuanxi, Yang

    2006-03-01

    Cadmium is a potential carcinogenic environmental and occupational pollutant. A wide variety of mutagens have been shown to cause DNA damage, but it is not yet clear whether the DNA damage is relative to inducement of mutations. DNA damage and the formation of mutations at the hypoxanthine guanine phosphoribosyl trans ferase (HPRT) induced by cadmium chloride (CdCl(2)) were investigated with rat lymphocytes and V79 Chinese hamster lung cells. The hprt mutant frequency (MF) assay was used as the method to measure gene mutation in the rat lymphocytes and V79 cells exposed to CdCl(2), and comet assay analysis was performed to detect DNA lesion and repair in CdCl(2)-induced V79 cells. The results showed that CdCl(2) treatment caused a strong genotoxic effect and a marginal effect on the frequency of gene mutations. The hprt mutant frequencies in the rat lymphocytes and V79 cells exposed to CdCl(2) were statistically higher than those of the negative control. There was statistical significance in TL, TD and percentage of comet cell with tails. CdCl(2) treatment can induce DNA single-strand breaks. There was a dose-dependent increase between CdCl(2) and DNA lesion. After cells were treated with CdCl(2) and hydrogen peroxide (H(2)O(2)), the TL and TD declined with repair time increasing, which indicated that DNA damages were repaired gradually. However, DNA repair with treatment of CdCl(2) was slower than that of H(2)O(2) in V79 cells, which suggests that CdCl(2) affected DNA repair of damaged cells. The study also showed that the hprt MF and comet assay can be used for genotoxicity testing of heavy metals. DNA damage detected with the comet assay may be relative to mutagenesis.

  12. Uterine tubal cells remain uninfected after culture with in vitro-produced embryos exposed to bovine viral diarrhea virus.

    PubMed

    Givens, M D; Galik, P K; Riddell, K P; Stringfellow, D A

    1999-10-01

    Bovine viral diarrhea virus (BVDV) has been isolated from washed and sonicated, in vitro-produced embryos, but the infectivity of BVDV associated with intact, developing, embryos has not been demonstrated. The objective of this study was to determine if a dose of BVDV infective for co-culture cells was associated with individual, developing embryos, following artificial exposure to the virus and washing. In 5 replicates, zona pellucida-intact, in vitro-produced embryos were assigned to a negative control embryo group, or were incubated in 10(5)-10(6) cell culture infective doses (50%, CCID50) per milliliter of a type I, noncytopathic (strain SD-1) BVDV for 2 h. Unexposed negative control embryos and exposed positive control embryos were washed, sonicated and assayed for BVDV using virus isolation with immunoperoxidase monolayer assay. Immediately or following cryopreservation, remaining virally-exposed, washed embryos were co-cultured individually with BVDV-negative cultures of bovine uterine tubal cells in a medium free of BVDV-neutralizing activity. After two days in culture, uterine tubal cells and embryos (including the zona pellucida) were separated and washed. The culture medium, uterine tubal cells and embryos were then assayed for BVDV. Bovine viral diarrhea virus was not isolated from any negative control embryo group, but was isolated from all positive control embryo groups. Although all uterine tubal cell populations were confirmed to be susceptible to BVDV, virus was never isolated from uterine tubal cells or embryos from post-exposure culture. In conclusion, although BVDV remains associated with washed in vitro-produced embryos, the virus associated with unsonicated embryos was not infective for uterine tubal cells in vitro.

  13. Ornithine decarboxylase activity is affected in primary astrocytes but not in secondary cell lines exposed to 872 MHz RF radiation.

    PubMed

    Höytö, A; Juutilainen, J; Naarala, J

    2007-06-01

    The effects of radiofrequency (RF) radiation on cellular ornithine decarboxylase (ODC) activity were studied in fibroblasts, two neural cell lines and primary astrocytes. Several exposure times and exposure levels were used, and the fields were either unmodulated or modulated according to the characteristics of the Global System for Mobile (GSM) communications. Murine L929 fibroblasts, rat C6 glioblastoma cells, human SH-SY5Y neuroblastoma cells, and rat primary astrocytes were exposed to RF radiation at 872 MHz in a waveguide exposure chamber equipped with water cooling. Cells were exposed for 2, 8, or 24 hours to continuous wave (CW) RF radiation or to a GSM type signal pulse modulated at 217 Hz, at specific absorption rates of 1.5, 2.5, or 6.0 W/kg. Cellular ODC activities of cell samples were assayed. ODC activity in rat primary astrocytes was decreased statistically significantly (p values from 0.003 to <0.001) and consistently in all experiments performed at two exposure levels (1.5 and 6.0 W/kg) and using GSM modulated or CW radiation. In the secondary cell lines, ODC activity was generally not affected. ODC activity was affected by RF radiation in rat primary neural cells, but the secondary cells used in this study showed essentially no response to similar RF radiation. In contrast to some previous studies, no differences between the modulated and continuous wave signals were detected. Further studies with primary astrocytes are warranted to confirm the present findings and to explore the mechanisms of the effects.

  14. Abnormal regulation of DNA replication and increased lethality in ataxia telangiectasia cells exposed to carcinogenic agents

    SciTech Connect

    Jaspers, N.G.; de Wit, J.; Regulski, M.R.; Bootsma, D.

    1982-01-01

    The effect of different carcinogenic agents on the rate of semiconservative DNA replication in normal and ataxia telangiectasis (AT) cells was investigated. The rate of DNA synthesis in all AT cell strains tested was depressed to a significantly lesser extent than in normal cells after exposure to X-rays under oxia or hypoxia or to bleomycin, agents to which AT cells are hypersensitive. In contrast, inhibition of DNA replication in normal human and AT cells was similar after treatment with some DNA-methylating agents or mitomycin C. Colony-forming ability of AT cells treated with these agents was not different from normal cells. Treatment with 4-nitroquinoline 1-oxide elicited a variable response in both AT and normal cell strains. In some strains, including those shown to be hypersensitive to the drug by other workers, the inhibition of DNA synthesis was more pronounced than in other cell strains, but no significant difference between AT and normal cells could be detected. The rejoining of DNA strand breaks induced by X-rays, measured by DNA elution techniques, occurred within l2 hr after treatment and could not be correlated with the difference in DNA synthesis inhibition in AT and normal cells. After low doses of X-rays, AT cells rejoined single-strand breaks slightly more slowly than did normal cells. The rate of DNA replication in X-irradiation AT and normal cells was not affected by nicotinamide, an inhibitor of poly(adenosine diphosphate ribose) synthesis. These data indicate that the diminished inhibition of DNA replication in carcinogen-treated AT cells (a) is a general characteristic of all AT cell strains, (b) correlates with AT cellular hypersensitivity, (c) is not directly caused by the bulk of the DNA strand breaks produced by carcinogenic agents, and (d) is not based on differences in the induction of poly(adenosine diphosphate ribose) synthesis between X-irradiated AT and normal cells.

  15. Olfactory ensheathing cell-conditioned medium protects astrocytes exposed to hydrogen peroxide stress.

    PubMed

    Jinbo, Liu; Zhiyuan, Liu; Zhijian, Zhang; WenGe, Ding

    2013-07-01

    The purpose of this study was to observe the effects of olfactory ensheathing cell conditioned medium (OECCM) on damaged astrocytes after exposure to H2O2 in vitro. OECCM was used to treat astrocytes after injury, which was induced by exposure to 500 μmol/L H2O2 for 20 min. The cell morphology was then observed under a light microscope, cell viability assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, cell ultrastructure observed with transmission electron microscopy (TEM), and apoptosis assessed by Annexin V staining followed by cytometry and Western blot. H2O2 induced severe damage to astrocytes as evidenced by decreased cell number, pathological changes in cell morphology, and significantly elevated cell apoptosis. Cells incubated with OECCM displayed significantly improved cell viability and decreased cell apoptotic rate. Under TEM, H2O2-treated cells showed partially broken plasma membranes, swollen rough endoplasmic reticula, visible vacuoles, and swollen or deformed mitochondria with ruptured cristae. Incubation with OECCM significantly ameliorated these pathological changes in astrocytes. These results suggest that OECCM may protect astrocytes from oxidative damage by promoting cell survival while reducing apoptosis of the damaged cells.

  16. Chromosome aberration and micronucleus frequencies in Allium cepa cells exposed to petroleum polluted water--a case study.

    PubMed

    Leme, Daniela Morais; Marin-Morales, Maria Aparecida

    2008-01-31

    In the present study, we applied Chromosome Aberration (CA) and Micronucleus (MN) tests to Allium cepa root cells, in order to evaluate the water quality of Guaecá river. This river, located in the city of São Sebastião, SP, Brazil, had been affected by an oil pipeline leak. Chemical analyses of Total Petroleum Hydrocarbons (TPHs) and Polycyclic Aromatic Hydrocarbons (PAHs) were also carried out in water samples, collected in July 2005 (dry season) and February 2006 (rainy season) in 4 different river sites. The largest CA and MN incidence in the meristematic cells of A. cepa was observed after exposure to water sample collected during the dry season, at the spring of the river, where the oil leak has arisen. The F(1) cells from roots exposed to such sample (non-merismatic region) were also analyzed for the incidence of MN, showing a larger frequency of irregularities, indicating a possible development of CA into MN. Lastly, our study reveals a direct correlation between water chemical analyses (contamination by TPHs and PAHs) and both genotoxic and mutagenic effects observed in exposed A. cepa cells.

  17. Phenotypically resembling myeloid derived suppressor cells are increased in children with HIV and exposed/infected with Mycobacterium tuberculosis.

    PubMed

    Du Plessis, Nelita; Jacobs, Ruschca; Gutschmidt, Andrea; Fang, Zhuo; van Helden, Paul D; Lutz, Manfred B; Hesseling, Anneke C; Walzl, Gerhard

    2017-01-01

    Increased disease susceptibility during early life has been linked to immune immaturity, regulatory T-cell/TH2 immune biasing and hyporesponsiveness. The contribution of myeloid derived suppressor cells (MDSCs) remains uninvestigated. Here, we assessed peripheral MDSC in HIV-infected and -uninfected children with tuberculosis (TB) disease before, during and after TB treatment, along with matched household contacts (HHCs), HIV-exposed, -infected and -uninfected children without recent TB exposure. Serum analytes and enzymes associated with MDSC accumulation/activation/function were measured by colorimetric- and fluorescence arrays. Peripheral frequencies of cells phenotypically resembling MDSCs were significantly increased in HIV-exposed uninfected (HEU) and M.tb-infected children, but peaked in children with TB disease and remained high following treatment. MDSC in HIV-infected (HI) children were similar to unexposed uninfected controls; however, HAART-mediated MDSC restoration to control levels could not be disregarded. Increased MDSC frequencies in HHC coincided with enhanced indoleamine-pyrrole-2,3-dioxygenase (IDO), whereas increased MDSC in TB cases were linked to heightened IDO and arginase-1. Increased MDSC were paralleled by reduced plasma IP-10 and thrombospondin-2 levels in HEU and significantly increased plasma IL-6 in HI HHC. Current investigations into MDSC-targeted treatment strategies, together with functional analyses of MDSCs, could endorse these cells as novel innate immune regulatory mechanism of infant HIV/TB susceptibility. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Roles of TauT and system A in cytoprotection of rat syncytiotrophoblast cell line exposed to hypertonic stress.

    PubMed

    Nishimura, T; Sai, Y; Fujii, J; Muta, M; Iizasa, H; Tomi, M; Deureh, M; Kose, N; Nakashima, E

    2010-11-01

    The purpose of this study was to clarify the cytoprotective mechanism(s) induced in a conditionally immortalized syncytiotrophoblast cell line (TR-TBT 18d-1) exposed to hypertonic conditions. Hypertonicity-induced apoptosis of TR-TBT 18d-1 cells, but this was blocked by addition of 1 mM taurine to the culture medium. TauT-knockdown using siRNA revealed that TauT is a major contributor to taurine uptake by TR-TBT 18d-1 cells, at least under normal conditions. Cellular uptake of [(3)H]taurine and [(14)C]betaine by TR-TBT 18d-1 cells cultured under hypertonic conditions was increased compared to that under normal conditions. TauT, BGT-1, ATA2 and HSP70 mRNAs were upregulated by hypertonicity, while OCTN2, ENT1 and CNT1 mRNAs were downregulated. [(3)H]Taurine uptake was strongly inhibited by TauT inhibitors such as hypotaurine and β-alanine. MeAIB, a system A specific substrate, inhibited hypertonic stress-induced [(14)C]betaine uptake. These results suggest that TauT and system A play cytoprotective roles in syncytiotrophoblasts exposed to hypertonic stress. Copyright © 2010 Elsevier Ltd. All rights reserved.

  19. Effect of amygdalin on the proliferation of hyperoxia-exposed type II alveolar epithelial cells isolated from premature rat.

    PubMed

    Zhu, Huaping; Chang, Liwen; Li, Wenbin; Liu, Hanchu

    2004-01-01

    The pathogenesis of hyperoxia lung injury and the mechanism of amygdalin on type 2 alveolar epithelial cells (AEC2) isolated from premature rat lungs in vitro were investigated. AEC2 were obtained by primary culture from 20-days fetal rat lung and hyperoxia-exposed cell model was established. Cell proliferating viability was examined by MTT assay after treatment of amygdalin at various concentrations. DNA content and the proliferating cell nuclear antigen (PCNA) protein expression of AEC2 were measured by using flow cytometry and immunocytochemistry respectively after 24 h of hyperoxia exposure or amygdalin treatment. The results showed that hyperoxia inhibited the proliferation and decreased PCNA protein expression in A-EC2 of premature rat in vitro. Amygdalin at the concentration range of 50-200 micromol/L stimulated the proliferation of AEC2 in a dose-dependent manner, however, 400 micromol/L amygdalin inhibited the proliferation of AEC2. Amygdalin at the concentration of 200 micromol/L played its best role in facilitating proliferation of AEC2s in vitro and could partially ameliorated the changes of proliferation in hyperoxia exposed AEC2 of premature rat. It has been suggested that hyperoxia inhibited the proliferation of AEC2s of premature rat, which may contribute to hyperoxia lung injury. Amygdalin may play partial protective role in hyperoxia-induced lung injury.

  20. Global transcriptomic analysis of model human cell lines exposed to surface-modified gold nanoparticles: the effect of surface chemistry

    NASA Astrophysics Data System (ADS)

    Grzincic, E. M.; Yang, J. A.; Drnevich, J.; Falagan-Lotsch, P.; Murphy, C. J.

    2015-01-01

    Gold nanoparticles (Au NPs) are attractive for biomedical applications not only for their remarkable physical properties, but also for the ease of which their surface chemistry can be manipulated. Many applications involve functionalization of the Au NP surface in order to improve biocompatibility, attach targeting ligands or carry drugs. However, changes in cells exposed to Au NPs of different surface chemistries have been observed, and little is known about how Au NPs and their surface coatings may impact cellular gene expression. The gene expression of two model human cell lines, human dermal fibroblasts (HDF) and prostate cancer cells (PC3) was interrogated by microarray analysis of over 14 000 human genes. The cell lines were exposed to four differently functionalized Au NPs: citrate, poly(allylamine hydrochloride) (PAH), and lipid coatings combined with alkanethiols or PAH. Gene functional annotation categories and weighted gene correlation network analysis were used in order to connect gene expression changes to common cellular functions and to elucidate expression patterns between Au NP samples. Coated Au NPs affect genes implicated in proliferation, angiogenesis, and metabolism in HDF cells, and inflammation, angiogenesis, proliferation apoptosis regulation, survival and invasion in PC3 cells. Subtle changes in surface chemistry, such as the initial net charge, lability of the ligand, and underlying layers greatly influence the degree of expression change and the type of cellular pathway affected.Gold nanoparticles (Au NPs) are attractive for biomedical applications not only for their remarkable physical properties, but also for the ease of which their surface chemistry can be manipulated. Many applications involve functionalization of the Au NP surface in order to improve biocompatibility, attach targeting ligands or carry drugs. However, changes in cells exposed to Au NPs of different surface chemistries have been observed, and little is known about how

  1. Gene expression profiling and pathway analysis of human bronchial epithelial cells exposed to airborne particulate matter collected from Saudi Arabia

    SciTech Connect

    Sun, Hong; Shamy, Magdy; Kluz, Thomas; Muñoz, Alexandra B.; Zhong, Mianhua; Laulicht, Freda; Alghamdi, Mansour A.; Khoder, Mamdouh I.; Chen, Lung-Chi; Costa, Max

    2012-12-01

    Epidemiological studies have established a positive correlation between human mortality and increased concentration of airborne particulate matters (PM). However, the mechanisms underlying PM related human diseases, as well as the molecules and pathways mediating the cellular response to PM, are not fully understood. This study aims to investigate the global gene expression changes in human cells exposed to PM{sub 10} and to identify genes and pathways that may contribute to PM related adverse health effects. Human bronchial epithelial cells were exposed to PM{sub 10} collected from Saudi Arabia for 1 or 4 days, and whole transcript expression was profiled using the GeneChip human gene 1.0 ST array. A total of 140 and 230 genes were identified that significantly changed more than 1.5 fold after PM{sub 10} exposure for 1 or 4 days, respectively. Ingenuity Pathway Analysis revealed that different exposure durations triggered distinct pathways. Genes involved in NRF2-mediated response to oxidative stress were up-regulated after 1 day exposure. In contrast, cells exposed for 4 days exhibited significant changes in genes related to cholesterol and lipid synthesis pathways. These observed changes in cellular oxidative stress and lipid synthesis might contribute to PM related respiratory and cardiovascular disease. -- Highlights: ► PM exposure modulated gene expression and associated pathways in BEAS-2B cells. ► One-day exposure to PM induced genes involved in responding to oxidative stress. ► 4-day exposure to PM changed genes associated to cholesterol and lipid synthesis.

  2. Transcriptional expression levels of cell stress marker genes in the Pacific oyster Crassostrea gigas exposed to acute thermal stress

    PubMed Central

    Farcy, Émilie; Voiseux, Claire; Lebel, Jean-Marc

    2008-01-01

    During the annual cycle, oysters are exposed to seasonal slow changes in temperature, but during emersion at low tide on sunny summer days, their internal temperature may rise rapidly, resulting in acute heat stress. We experimentally exposed oysters to a 1-h acute thermal stress and investigated the transcriptional expression level of some genes involved in cell stress defence mechanisms, including chaperone proteins (heat shock proteins Hsp70, Hsp72 and Hsp90 (HSP)), regulation of oxidative stress (Cu-Zn superoxide dismutase, metallothionein (MT)), cell detoxification (glutathione S-transferase sigma, cytochrome P450 and multidrug resistance (MDR1)) and regulation of the cell cycle (p53). Gene mRNA levels were quantified by reverse transcription-quantitative polymerase chain reaction and expressed as their ratio to actin mRNA, used as a reference. Of the nine genes studied, HSP, MT and MDR1 mRNA levels increased in response to thermal stress. We compared the responses of oysters exposed to acute heat shock in summer and winter and observed differences in terms of magnitude and kinetics. A larger increase was observed in September, with recovery within 48 h, whereas in March, the increase was smaller and lasted more than 2 days. The results were also compared with data obtained from the natural environment. Though the functional molecule is the protein and information at the mRNA level only has limitations, the potential use of mRNAs coding for cell stress defence proteins as early sensitive biomarkers is discussed. PMID:19002605

  3. Morphologic, biochemical, and cytogenetic studies of bone marrow and circulating blood cells in painters exposed to ethylene glycol ethers.

    PubMed

    Cullen, M R; Solomon, L R; Pace, P E; Buckley, P; Duffy, T P; McPhedran, P; Kelsey, K T; Redlich, C A

    1992-10-01

    In a previous cross-sectional survey, up to 15% of shipyard painters were found to have mild anemia or granulocytopenia, mostly acquired since employment. Environmental studies had suggested a possible etiologic role for ethylene glycol ethers, solvents to which the men were heavily exposed and which have established myelotoxic potential. To exclude alternative hypotheses, examine possible common patterns of injury, and identify potential risk factors and markers for such an effect, the affected painters were further studied. The painters were matched with two groups of controls: exposed painters without evidence of hematologic abnormality on the previous survey and unexposed controls. Altogether 25 subjects were studied by histopathologic examination of bone marrow, cytogenetic studies of marrow cells, and peripheral lymphocytes and peripheral red cell studies of membrane and metabolic function. Except for an unexpected finding of a race-associated effect on marrow histology, insignificant differences were seen among the groups in terms of marrow morphology and cellularity, stem cell growth kinetics, and marrow or peripheral cytogenetics. Two metabolic abnormalities of peripheral red cells related to exposure or clinical status of the subjects were found. Pyruvate kinase, an established marker of acquired myelodysplasia, was significantly depressed in the subjects with previously abnormal counts. Although reduced glutathione levels and holoenzyme activities of glutathione reductase (GSHR) did not differ among groups, exposed subjects had decreased saturation of GSHR with flavin adenine dinucleotide which could be restored in vitro, suggesting riboflavin deficiency or impaired riboflavin metabolism. Thus, although a unique pattern of bone marrow injury by histologic or genetic assay attributable to ethylene glycol ethers was not defined, biochemical effects of possible mechanistic importance were identified. The relevance of these findings as subclinical disease

  4. Effects of low intensity static electromagnetic radiofrequency fields on leiomyosarcoma and smooth muscle cell lines.

    PubMed

    Karkabounas, Spyridon; Havelas, Konstantinos; Kostoula, Olga K; Vezyraki, Patra; Avdikos, Antonios; Binolis, Jayne; Hatziavazis, George; Metsios, Apostolos; Verginadis, Ioannis; Evangelou, Angelos

    2006-01-01

    In this study we investigated the effects of low intensity static radiofrequency electromagnetic field (EMF) causing no thermal effects, on leiomyosarcoma cells (LSC), isolated from tumors of fifteen Wistar rats induced via a 3,4-benzopyrene injection. Electromagnetic resonance frequencies measurements and exposure of cells to static EMF were performed by a device called multi channel dynamic exciter 100 V1 (MCDE). The LSC were exposed to electromagnetic resonance radiofrequencies (ERF) between 10 kHz to 120 kHz, for 45 min. During a 24h period, after the exposure of the LSC to ERF, there was no inhibition of cells proliferation. In contrast, at the end of a 48 h incubation period, LSC proliferation dramatically decreased by more than 98% (P<0.001). At that time, the survived LSC were only 2% of the total cell population exposed to ERF, and under the same culture conditions showed significant decrease of proliferation. These cells were exposed once again to ERF for 45 min (totally 4 sessions of exposure, of 45 min duration each) and tested using a flow cytometer. Experiments as above were repeated five times. It was found that 45% of these double exposed to ERF, LSC (EMF cells) were apoptotic and only a small percentage 2%, underwent mitosis. In order to determinate their metastatic potential, these EMF cells were also counted and tested by an aggregometer for their ability to aggregate platelets and found to maintain this ability., since they showed no difference in platelet aggregation ability compared to the LSC not exposed to ERF (control cells). In conclusion, exposure of LSC to specific ERF, decreases their proliferation rate and induces cell apoptosis. Also, the LSC that survived after exposed to ERF, had a lower proliferation rate compared to the LSC controls (P<0.05) but did not loose their potential for metastases (platelet aggregation ability). The non-malignant SMC were not affected by the EMF exposure (P<0.4). The specific ERF generated from the MCDE

  5. Friend leukemia virus transformed cells exposed to microgravity in the presence of DMSO (7-IML-1)

    NASA Technical Reports Server (NTRS)

    Cogoli, Augusto

    1992-01-01

    The purpose of this experiment is to study the adaptation of living cells to microgravity. The in vitro transformation of Friend cells by Dimethylsufoxide (DMSO) is a good model for the study of cell differentiation and protein biosynthesis. Cultures of cells will be prepared shortly before launch. Once in space, transformation will be induced by injection of DMSO. One set of cultures will be chemically fixed with glutaraldehyde for electron microscope investigations; another set will be preserved for determining the amount of hemogloben produced and the extent of cell proliferation.

  6. Comparison of photovoltaic cell temperatures in modules operating with exposed and enclosed back surfaces

    NASA Technical Reports Server (NTRS)

    Namkoong, D.; Simon, F. F.

    1981-01-01

    Four different photovoltaic module designs were tested to determine the cell temperature of each design. The cell temperatures were compared to those obtained on identical design, using the same nominal operating cell temperature (NOCT) concept. The results showed that the NOCT procedure does not apply to the enclosed configurations due to continuous transient conditions. The enclosed modules had higher cell temperatures than the open modules, and insulated modules higher than the uninsulated. The severest performance loss - when translated from cell temperatures - 17.5 % for one enclosed, insulated module as a compared to that module mounted openly.

  7. Human Micro- and Macrovascular Endothelial Cells Exposed to Simulated Microgravity Upregulate hsp70

    NASA Astrophysics Data System (ADS)

    Mariotti, M.; Maier, J. A. M.

    2009-01-01

    Microgravity is known to have adverse effects on the eukaryotic cells. Here we report that microgravity affects the behaviour of human micro- and macro-vascular endothelial cells. To simulate microgravity we have utilized a NASA-developed bioreactor, the Rotating Wall Vessel (RWV). Macrovascular cells proliferate faster in the RWV than controls and, accordingly, downregulate p21, which inhibits the transition from the G1 to the S phase. On the contrary, microvascular cells are growth retarded in simulated microgravity and upregulate p21. No apoptosis was detected in both the cell types. In parallel, upregulation of heat shock protein (hsp) 70 was observed in the two cell types. Because it is reported the hsp70 increases endothelial survival, we hypothesize that hsp70 induction might protect against apoptosis. Hsp70 upregulation might therefore represent an important adaptive response of human endothelial cells to simulated microgravity.

  8. Global analysis of fungal morphology exposes mechanisms of host cell escape.

    PubMed

    O'Meara, Teresa R; Veri, Amanda O; Ketela, Troy; Jiang, Bo; Roemer, Terry; Cowen, Leah E

    2015-03-31

    Developmental transitions between single-cell yeast and multicellular filaments underpin virulence of diverse fungal pathogens. For the leading human fungal pathogen Candida albicans, filamentation is thought to be required for immune cell escape via induction of an inflammatory programmed cell death. Here we perform a genome-scale analysis of C. albicans morphogenesis and identify 102 negative morphogenetic regulators and 872 positive regulators, highlighting key roles for ergosterol biosynthesis and N-linked glycosylation. We demonstrate that C. albicans filamentation is not required for escape from host immune cells; instead, macrophage pyroptosis is driven by fungal cell-wall remodelling and exposure of glycosylated proteins in response to the macrophage phagosome. The capacity of killed, previously phagocytized cells to drive macrophage lysis is also observed with the distantly related fungal pathogen Cryptococcus neoformans. This study provides a global view of morphogenetic circuitry governing a key virulence trait, and illuminates a new mechanism by which fungi trigger host cell death.

  9. A nitroimidazole derivative, PR-350, enhances the killing of pancreatic cancer cells exposed to high-dose irradiation under hypoxia.

    PubMed

    Mizumoto, Kazuhiro; Qian, Li-Wu; Zhang, Li; Nagai, Eishi; Kura, Shinobu; Tanaka, Masao

    2002-03-01

    The radiosensitizing effects of PR-350, a nitroimidazole derivative, were examined concerning the cell killing of human pancreatic cancer cell lines exposed to high doses of gamma-ray irradiation in vitro. The percentages of dead cells were analyzed with a multiwell plate reader to measure the fluorescence intensity of propidium iodide before and after a digitonin treatment. The sensitizing effect of PR-350 on cell killing by high-dose irradiation was confirmed by time-course, dose-dependency, and microscopic observations. In five of seven pancreatic cancer cell lines in which the number of dead cells was determined 5 days after 30 Gy irradiation in the presence of PR-350, the number was significantly increased under hypoxic conditions, but not under aerobic conditions. The selective radiosensitive effect of PR-350 on hypoxic cells was also confirmed by flow cytometry. The results indicate that PR-350 can enhance the killing of pancreatic cancer cells by high-dose irradiation under hypoxia, which supports its clinical radiosensitizing effects when administered during intraoperative irradiation to pancreatic cancer.

  10. Morphological alterations of Vero cell exposed to coplanar PCB 126 and noncoplanar PCB 153.

    PubMed

    Shen, Kaili; Shen, Chaofeng; Chen, Lei; Chen, Xincai; Chen, Yingxu

    2012-01-01

    Polychlorinated biphenyls (PCBs) are widespread, persistent environmental contaminants that display a complex spectrum of toxicological properties. Exposure to PCBs has been associated with morphological anomalies in cell cultures. However, most mechanistic studies of PCBs' toxic activity have been focused on coplanar congeners. It is of importance to determine whether PCB treatment would influence cell configuration and whether these changes would depend on the structural characteristics of PCBs. In this study, we investigated cell morphological alteration in Vero cell cultures after exposure to coplanar PCB 126 and noncoplanar PCB 153. The survival of Vero cells was measured through the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) test. Cytotoxicity results suggested that PCB congeners had a toxic, antiproliferative effect on Vero cells. Morphological studies described structural modifications and provided evidence that apoptosis might be the main cell death pathway in PCB 153-treated cells. The comparison between PCB 126 and PCB 153 indicated that the cell death mechanisms involved in coplanar or noncoplanar PCB congener exposure were different in Vero cells.

  11. Metabolomics reveals metabolic changes in male reproductive cells exposed to thirdhand smoke

    SciTech Connect

    Xu, Bo; Chen, Minjian; Yao, Mengmeng; Ji, Xiaoli; Mao, Zhilei; Tang, Wei; Qiao, Shanlei; Schick, Suzaynn F.; Mao, Jian-Hua; Hang, Bo; Xia, Yankai

    2015-10-22

    Thirdhand smoke (THS) is a new term for the toxins in cigarette smoke that linger in the environment long after the cigarettes are extinguished. The effects of THS exposure on male reproduction have not yet been studied. In this study, metabolic changes in male germ cell lines (GC-2 and TM-4) were analyzed after THS treatment for 24 h. THS-loaded chromatography paper samples were generated in a laboratory chamber system and extracted in DMEM. At a paper: DMEM ratio of 50 μg/ml, cell viability in both cell lines was normal, as measured by the MTT assay and markers of cytotoxicity, cell cycle, apoptosis and ROS production were normal as measured by quantitative immunofluorescence. Metabolomic analysis was performed on methanol extracts of GC-2 and TM-4 cells. Furthermore, glutathione metabolism in GC-2 cells, and nucleic acid and ammonia metabolism in TM-4 cells, was changed significantly by THS treatment. RT-PCR analyses of mRNA for enzyme genes Gss and Ggt in GC-2 cells, and TK, SMS and Glna in TM-4 cells reinforced these findings, showing changes in the levels of enzymes involved in the relevant pathways. In conclusion, exposure to THS at very low concentrations caused distinct metabolic changes in two different types of male reproductive cell lines.

  12. Metabolomics reveals metabolic changes in male reproductive cells exposed to thirdhand smoke

    NASA Astrophysics Data System (ADS)

    Xu, Bo; Chen, Minjian; Yao, Mengmeng; Ji, Xiaoli; Mao, Zhilei; Tang, Wei; Qiao, Shanlei; Schick, Suzaynn F.; Mao, Jian-Hua; Hang, Bo; Xia, Yankai

    2015-10-01

    Thirdhand smoke (THS) is a new term for the toxins in cigarette smoke that linger in the environment long after the cigarettes are extinguished. The effects of THS exposure on male reproduction have not yet been studied. In this study, metabolic changes in male germ cell lines (GC-2 and TM-4) were analyzed after THS treatment for 24 h. THS-loaded chromatography paper samples were generated in a laboratory chamber system and extracted in DMEM. At a paper: DMEM ratio of 50 μg/ml, cell viability in both cell lines was normal, as measured by the MTT assay and markers of cytotoxicity, cell cycle, apoptosis and ROS production were normal as measured by quantitative immunofluorescence. Metabolomic analysis was performed on methanol extracts of GC-2 and TM-4 cells. Glutathione metabolism in GC-2 cells, and nucleic acid and ammonia metabolism in TM-4 cells, was changed significantly by THS treatment. RT-PCR analyses of mRNA for enzyme genes Gss and Ggt in GC-2 cells, and TK, SMS and Glna in TM-4 cells reinforced these findings, showing changes in the levels of enzymes involved in the relevant pathways. In conclusion, exposure to THS at very low concentrations caused distinct metabolic changes in two different types of male reproductive cell lines.

  13. Ultrastructural changes in hepatic sinusoidal endothelial cells acutely exposed to colloidal iron.

    PubMed

    Bassett, Mark L; Dahlstrom, Jane E; Taylor, Matthew C; Koina, Mark E; Maxwell, Lesley; Francis, Douglas; Jain, Sanjiv; McLean, Allan J

    2003-07-01

    Hepatic sinusoidal endothelial cells form an important interface between the vascular system, represented by the sinusoids, and the space of Disse that surrounds the hepatocyte microvilli. This study aimed to assess the light microscopic and ultrastructural effects of acute exposure of hepatic sinusoidal endothelial cells to colloidal iron by injection of rats with iron polymaltose. Eight minutes after a single intravenous injection of iron polymaltose sinusoidal endothelial cells showed defenestration, and thickening and layering as assessed by transmission electron microscopy. Kupffer cells and stellate cells appeared activated. These changes were not observed in control animals, experiments using equivalent doses of maltose, or experiments using colloidal carbon except for Kupffer cell activation due to colloidal carbon. No significant light microscopic changes were seen in study or control animals. The findings indicate that acute exposure to colloidal iron causes changes in hepatic sinusoidal endothelial cells, stellate cells and Kupffer cells. This may be the result of a direct toxic effect of iron or increased production of reactive oxygen species. These observations suggest a possible mechanism for defenestration of sinusoidal endothelial cells in ageing and in disease states.

  14. Metabolomics reveals metabolic changes in male reproductive cells exposed to thirdhand smoke

    PubMed Central

    Xu, Bo; Chen, Minjian; Yao, Mengmeng; Ji, Xiaoli; Mao, Zhilei; Tang, Wei; Qiao, Shanlei; Schick, Suzaynn F.; Mao, Jian-Hua; Hang, Bo; Xia, Yankai

    2015-01-01

    Thirdhand smoke (THS) is a new term for the toxins in cigarette smoke that linger in the environment long after the cigarettes are extinguished. The effects of THS exposure on male reproduction have not yet been studied. In this study, metabolic changes in male germ cell lines (GC-2 and TM-4) were analyzed after THS treatment for 24 h. THS-loaded chromatography paper samples were generated in a laboratory chamber system and extracted in DMEM. At a paper: DMEM ratio of 50 μg/ml, cell viability in both cell lines was normal, as measured by the MTT assay and markers of cytotoxicity, cell cycle, apoptosis and ROS production were normal as measured by quantitative immunofluorescence. Metabolomic analysis was performed on methanol extracts of GC-2 and TM-4 cells. Glutathione metabolism in GC-2 cells, and nucleic acid and ammonia metabolism in TM-4 cells, was changed significantly by THS treatment. RT-PCR analyses of mRNA for enzyme genes Gss and Ggt in GC-2 cells, and TK, SMS and Glna in TM-4 cells reinforced these findings, showing changes in the levels of enzymes involved in the relevant pathways. In conclusion, exposure to THS at very low concentrations caused distinct metabolic changes in two different types of male reproductive cell lines. PMID:26489853

  15. Cadmium overkill: autophagy, apoptosis and necrosis signalling in endothelial cells exposed to cadmium.

    PubMed

    Messner, Barbara; Türkcan, Adrian; Ploner, Christian; Laufer, Günther; Bernhard, David

    2016-04-01

    Apoptosis, necrosis, or autophagy-it is the mode of cell demise that defines the response of surrounding cells and organs. In case of one of the most toxic substances known to date, cadmium (Cd), and despite a large number of studies, the mode of cell death induced is still unclear. As there exists conflicting data as to which cell death mode is induced by Cd both across various cell types and within a single one, we chose to analyse Cd-induced cell death in primary human endothelial cells by investigating all possibilities that a cell faces in undergoing cell death. Our results indicate that Cd-induced death signalling starts with the causation of DNA damage and a cytosolic calcium flux. These two events lead to an apoptosis signalling-related mitochondrial membrane depolarisation and a classical DNA damage response. Simultaneously, autophagy signalling such as ER stress and phagosome formation is initiated. Importantly, we also observed lysosomal membrane permeabilization. It is the integration of all signals that results in DNA degradation and a disruption of the plasma membrane. Our data thus suggest that Cd causes the activation of multiple death signals in parallel. The genotype (for example, p53 positive or negative) as well as other factors may determine the initiation and rate of individual death signals. Differences in the signal mix and speed may explain the differing results recorded as to the Cd-induced mode of cell death thus far. In human endothelial cells it is the sum of most if not all of these signals that determine the mode of Cd-induced cell death: programmed necrosis.

  16. Enhancement of B cell and monocyte populations in rats exposed to chlorpheniramine.

    PubMed

    Jung, Kyung-Jin; Choi, Woo-Hyuck; Park, Shin-Young; Lee, Sang-Hoon; Yoo, Jin-San; Koh, Woo Suk

    2012-12-01

    Chlorpheniramine is an anti-histamine agent on IgE-mediated inflammation. In order to investigate the immunomodulatory effects of chlorpheniramine, we assessed the changes of peripheral mononuclear cell populations and other general clinical parameters, including hematology and clinical chemistry, following chlorpheniramine administration in rats. Since prednisolone is commonly co-prescribed with anti-histamine in many hypersensitive reactions, we also examined the changes to compare the results after the prednisolone administration. Chlorpheniramine (50, 100 and 200 μg/kg) and prednisolone (1, 2 and 4 mg/kg) were intramuscularly administered to female Sprague-Dawley (SD) rats 3 times, at intervals of 1 week. Except the clinical signs, such as stiffness and abnormal gait due to the local toxicity at injection sites, no other significant changes in body weights, urinalysis, and macroscopic examination were noted in the animals given chlorpheniramine. On the other hand, white blood cells, especially B cells and monocytes, showed a dose-dependent increase in the chlorpheniramine-treated animals; whereas, the numbers of both B and T cells (helper T and cytotoxic T, NKT cells) were decreased in the prednisolone-treated animals. Taken together, these results suggest that chloropheniramine administration enhances white blood cells in the peripheral blood, mostly due to increases of the B cells and monocytes, but no T cells and NK cells.

  17. ATP Release from Human Airway Epithelial Cells Exposed to Staphylococcus aureus Alpha-Toxin

    PubMed Central

    Baaske, Romina; Richter, Mandy; Möller, Nils; Ziesemer, Sabine; Eiffler, Ina; Müller, Christian; Hildebrandt, Jan-Peter

    2016-01-01

    Airway epithelial cells reduce cytosolic ATP content in response to treatment with S. aureus alpha-toxin (hemolysin A, Hla). This study was undertaken to investigate whether this is due to attenuated ATP generation or to release of ATP from the cytosol and extracellular ATP degradation by ecto-enzymes. Exposure of cells to rHla did result in mitochondrial calcium uptake and a moderate decline in mitochondrial membrane potential, indicating that ATP regeneration may have been attenuated. In addition, ATP may have left the cells through transmembrane pores formed by the toxin or through endogenous release channels (e.g., pannexins) activated by cellular stress imposed on the cells by toxin exposure. Exposure of cells to an alpha-toxin mutant (H35L), which attaches to the host cell membrane but does not form transmembrane pores, did not induce ATP release from the cells. The Hla-mediated ATP-release was completely blocked by IB201, a cyclodextrin-inhibitor of the alpha-toxin pore, but was not at all affected by inhibitors of pannexin channels. These results indicate that, while exposure of cells to rHla may somewhat reduce ATP production and cellular ATP content, a portion of the remaining ATP is released to the extracellular space and degraded by ecto-enzymes. The release of ATP from the cells may occur directly through the transmembrane pores formed by alpha-toxin. PMID:27929417

  18. Chrondrogenesis in micromass cultures of embryonic mouse limb mesenchymal cells exposed to microgravity (7-IML-1)

    NASA Technical Reports Server (NTRS)

    Duke, Jackie

    1992-01-01

    A basic question of space biology is whether changes in gravity are perceived at the cellular level. Previous studies with a variety of cells have shown that this is the case, but to date the response of skeletal cells has not been examined, even though the skeleton is sensitive to gravitational changes. The objective of the CELLS Experiment is to examine the effect of microgravity in vitro on a skeletal cell known to be sensitive to gravitational changes both in vivo and in vitro - the mammalian chondrocyte. Various aspects of the experiment are discussed.

  19. Metabolomics reveals metabolic changes in male reproductive cells exposed to thirdhand smoke

    DOE PAGES

    Xu, Bo; Chen, Minjian; Yao, Mengmeng; ...

    2015-10-22

    Thirdhand smoke (THS) is a new term for the toxins in cigarette smoke that linger in the environment long after the cigarettes are extinguished. The effects of THS exposure on male reproduction have not yet been studied. In this study, metabolic changes in male germ cell lines (GC-2 and TM-4) were analyzed after THS treatment for 24 h. THS-loaded chromatography paper samples were generated in a laboratory chamber system and extracted in DMEM. At a paper: DMEM ratio of 50 μg/ml, cell viability in both cell lines was normal, as measured by the MTT assay and markers of cytotoxicity, cellmore » cycle, apoptosis and ROS production were normal as measured by quantitative immunofluorescence. Metabolomic analysis was performed on methanol extracts of GC-2 and TM-4 cells. Furthermore, glutathione metabolism in GC-2 cells, and nucleic acid and ammonia metabolism in TM-4 cells, was changed significantly by THS treatment. RT-PCR analyses of mRNA for enzyme genes Gss and Ggt in GC-2 cells, and TK, SMS and Glna in TM-4 cells reinforced these findings, showing changes in the levels of enzymes involved in the relevant pathways. In conclusion, exposure to THS at very low concentrations caused distinct metabolic changes in two different types of male reproductive cell lines.« less

  20. Chrondrogenesis in micromass cultures of embryonic mouse limb mesenchymal cells exposed to microgravity (7-IML-1)

    NASA Technical Reports Server (NTRS)

    Duke, Jackie

    1992-01-01

    A basic question of space biology is whether changes in gravity are perceived at the cellular level. Previous studies with a variety of cells have shown that this is the case, but to date the response of skeletal cells has not been examined, even though the skeleton is sensitive to gravitational changes. The objective of the CELLS Experiment is to examine the effect of microgravity in vitro on a skeletal cell known to be sensitive to gravitational changes both in vivo and in vitro - the mammalian chondrocyte. Various aspects of the experiment are discussed.

  1. Cutaneous Human Papillomaviruses Found in Sun-Exposed Skin: Beta-papillomavirus Species 2 Predominates in Squamous Cell Carcinoma

    PubMed Central

    Forslund, Ola; Iftner, Thomas; Andersson, Kristin; Lindelöf, Bernt; Hradil, Eva; Nordin, Peter; Stenquist, Bo; Kirnbauer, Reinhard; Dillner, Joakim; de Villiers, Ethel-Michele

    2013-01-01

    Background A spectrum of cutaneous human papillomaviruses (HPVs) is detectable in nonmelanoma skin cancers, as well as in healthy skin, but the significance that the presence of these types of HPV DNA has for the pathogenesis of skin cancer remains unclear. Methods We studied 349 nonimmunosuppressed patients with skin lesions (82 with squamous cell carcinomas, 126 with basal cell carcinomas, 49 with actinic keratoses, and 92 with benign lesions). After superficial skin had been removed by tape, paired biopsy samples—from the lesion and from healthy skin from the same patient—were tested for HPV DNA. Risk factors for HPV DNA were analyzed in multivariate models. Results Overall, 12% of healthy skin samples were positive for HPV DNA, compared with 26% of benign lesions, 22% of actinic keratoses, 18% of basal cell carcinomas, and 26% of squamous cell carcinomas. HPV DNA was associated with sites extensively exposed to the sun, both for the lesions (odds ratio [OR], 4.45 [95% confidence interval {CI}, 2.44–8.11]) and for the healthy skin samples (OR, 3.65 [95% CI 1.79–7.44]). HPV types of Beta-papillomavirus species 2 predominate in squamous cell carcinomas (OR, 4.40 [95% CI, 1.92–10.06]), whereas HPV types of Beta-papillomavirus species 1 are primarily found in benign lesions (OR, 3.47 [95% CI, 1.72–6.99]). Conclusions Cutaneous HPV types are primarily detected at sites extensively exposed to the sun. HPV types of Beta-papillomavirus species 2, but not of species 1, are associated with squamous cell carcinoma. PMID:17703418

  2. In vitro response of retinal pigment epithelial cells exposed to chitosan materials prepared with different cross-linkers.

    PubMed

    Lai, Jui-Yang; Li, Ya-Ting; Wang, Tsu-Pin

    2010-01-01

    The interaction between cells and biopolymers is the evaluation indicator of the biocompatibility of materials. The purpose of this work was to examine the responses of retinal pigment epithelial (RPE) cells to genipin (GP) or glutaraldehyde (GTA) cross-linked chitosan by means of cell viability assays, cytokine expression analyses, and apoptosis assays. Evaluations of non-cross-linked chitosan were conducted simultaneously for comparison. Both GP and GTA treated samples with the same extent of cross-linking (around 80%) were prepared by varying cross-linking time. Our results showed that GP cross-linking was carried out by either radical polymerization of the monomers or S(N)2 nucleophilic substitution reaction involving the replacement of the ester group on the monomer with a secondary amide linkage. On the other hand, GTA could react with free amino groups of chitosan, leading to the formation of either the Schiff bases or the Michael-type adducts with terminal aldehydes. The biocompatibility of non-cross-linked chitosan membranes was demonstrated by the absence of any signs of toxicity or inflammation reaction. The present study showed that the ARPE-19 cells exposed to GTA cross-linked chitosan membranes had significantly higher cytotoxicity, interleukin-6 levels, and number of TUNEL-positive nuclei than did those exposed to GP treated samples. In addition, the materials modified with GTA trigger apoptosis at an early stage and may induce toxicity in the RPE cells later. The findings suggest that while the chitosan molecules bridged by GP are satisfactorily cytocompatible, the counterparts treated by GTA do not seem to be tolerated. In terms of material safety, the GP cross-linked chitosan may be compatible with human RPE cells and may have a potential application as delivery carriers in the treatment of posterior segment diseases.

  3. An Inactivated Antibiotic-Exposed Whole-Cell Vaccine Enhances Bactericidal Activities Against Multidrug-Resistant Acinetobacter baumannii

    PubMed Central

    Shu, Meng-Hooi; MatRahim, NorAziyah; NorAmdan, NurAsyura; Pang, Sui-Ping; Hashim, Sharina H.; Phoon, Wai-Hong; AbuBakar, Sazaly

    2016-01-01

    Vaccination may be an alternative treatment for infection with multidrug-resistance (MDR) Acinetobacter baumannii. The study reported here evaluated the bactericidal antibody responses following immunization of mice using an inactivated whole-cell vaccine derived from antibiotic-exposed MDR A. baumannii (I-M28-47-114). Mice inoculated with I-M28-47 (non-antibiotic-exposed control) and I-M28-47-114 showed a high IgG antibody response by day 5 post-inoculation. Sera from mice inoculated with I-M28-47-114 collected on day 30 resulted in 80.7 ± 12.0% complement-mediated bacteriolysis in vitro of the test MDR A. baumannii treated with imipenem, which was a higher level of bacteriolysis over sera from mice inoculated with I-M28-47. Macrophage-like U937 cells eliminated 49.3 ± 11.6% of the test MDR A. baumannii treated with imipenem when opsonized with sera from mice inoculated with I-M28-47-114, which was a higher level of elimination than observed for test MDR A. baumannii opsonized with sera from mice inoculated with I-M28-47. These results suggest that vaccination with I-M28-47-114 stimulated antibody responses capable of mounting high bactericidal killing of MDR A. baumannii. Therefore, the inactivated antibiotic-exposed whole-cell vaccine (I-M28-47-114) has potential for development as a candidate vaccine for broad clearance and protection against MDR A. baumannii infections. PMID:26923424

  4. Novel type 1 photosensitizers: viability of leukemia cells exposed to reactive intermediates generated in situ by in vitro photofragmentation

    NASA Astrophysics Data System (ADS)

    Rajagopalan, Raghavan; Karwa, Amol; Lusiak, Przemyslaw M.; Srivastava, Kripa; Poreddy, Amruta R.; Pandurangi, Raghootama S.; Galen, Karen P.; Neumann, William L.; Cantrell, Gary E.; Dorshow, Richard B.

    2009-06-01

    Photodynamic therapy of tumors involving Type 2 photosenstizers has been conspicuously successful, but the Type 1 process, in contrast, has not received much attention despite its considerable potential. Accordingly, several classes of molecules containing fragile bonds such as azido (-N=N=N), azo (-N=N-), sulfenato (-S-O-) and oxaza (-N-O-) functional groups that produce reactive intermediates such as radicals and nitrenes upon photoexcitation were prepared and tested for cell viability using U397 leukemia cell line. The azido photosensitizer was conjugated to leukemia cell binding peptide, SFFWRLS, for targeted cell viability study. The cells were incubated with the photosensitizer at various concentrations, and were illuminated for 5, 10, and 20 minutes. The results show that all the photosensitizers caused cell death compared to the controls when exposed to both the photosensitizers and light. Most importantly, selective cell death was observed with the azido peptide conjugate 6, which clearly demonstrates that these Type 1 sensitizers are useful for phototherapeutic applications.

  5. Anti-Inflammatory Effects of Pomegranate Peel Extract in THP-1 Cells Exposed to Particulate Matter PM10.

    PubMed

    Park, Soojin; Seok, Jin Kyung; Kwak, Jun Yup; Suh, Hwa-Jin; Kim, Young Mi; Boo, Yong Chool

    2016-01-01

    Epidemiological and experimental evidence support health risks associated with the exposure to airborne particulate matter with a diameter of <10 μM (PM10). PM10 stimulates the production of reactive oxygen species (ROS) and inflammatory mediators. Thus, we assumed that natural antioxidants might provide health benefits attenuating hazardous effects of PM10. In the present study, we examined the effects of pomegranate peel extract (PPE) on THP-1 monocytic cells exposed to PM10. PM10 induced cytotoxicity and the production of ROS. It also increased the expression and secretion of inflammatory cytokines, such as tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and monocyte chemoattractant protein-1 (MCP-1), and cell adhesion molecules, such as intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1). PPE at 10-100 μg mL(-1) attenuated the production of ROS and the expression of TNF-α, IL-1β, MCP-1, and ICAM-1, but not VCAM-1, in THP-1 cells stimulated by PM10 (100 μg mL(-1)). PPE also attenuated the adhesion of PM10-stimulated THP-1 cells to EA.hy926 endothelial cells. PPE constituents, punicalagin and ellagic acid, attenuated PM10-induced monocyte adhesion to endothelial cells, and punicalagin was less cytotoxic compared to ellagic acid. The present study suggests that PPE and punicalagin may be useful in alleviating inflammatory reactions due to particulate matter.

  6. Anti-Inflammatory Effects of Pomegranate Peel Extract in THP-1 Cells Exposed to Particulate Matter PM10

    PubMed Central

    Park, Soojin; Seok, Jin Kyung; Kwak, Jun Yup; Suh, Hwa-Jin; Kim, Young Mi; Boo, Yong Chool

    2016-01-01

    Epidemiological and experimental evidence support health risks associated with the exposure to airborne particulate matter with a diameter of <10 μM (PM10). PM10 stimulates the production of reactive oxygen species (ROS) and inflammatory mediators. Thus, we assumed that natural antioxidants might provide health benefits attenuating hazardous effects of PM10. In the present study, we examined the effects of pomegranate peel extract (PPE) on THP-1 monocytic cells exposed to PM10. PM10 induced cytotoxicity and the production of ROS. It also increased the expression and secretion of inflammatory cytokines, such as tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and monocyte chemoattractant protein-1 (MCP-1), and cell adhesion molecules, such as intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1). PPE at 10–100 μg mL−1 attenuated the production of ROS and the expression of TNF-α, IL-1β, MCP-1, and ICAM-1, but not VCAM-1, in THP-1 cells stimulated by PM10 (100 μg mL−1). PPE also attenuated the adhesion of PM10-stimulated THP-1 cells to EA.hy926 endothelial cells. PPE constituents, punicalagin and ellagic acid, attenuated PM10-induced monocyte adhesion to endothelial cells, and punicalagin was less cytotoxic compared to ellagic acid. The present study suggests that PPE and punicalagin may be useful in alleviating inflammatory reactions due to particulate matter. PMID:27247608

  7. Protein thiol oxidation and formation of S-glutathionylated cyclophilin A in cells exposed to chloramines and hypochlorous acid.

    PubMed

    Stacey, Melissa M; Cuddihy, Sarah L; Hampton, Mark B; Winterbourn, Christine C

    2012-11-01

    Neutrophil oxidants, including the myeloperoxidase products, HOCl and chloramines, have been linked to endothelial dysfunction in inflammatory diseases such as atherosclerosis. As they react preferentially with sulfur centers, thiol proteins are likely to be cellular targets. Our objectives were to establish whether there is selective protein oxidation in vascular endothelial cells treated with HOCl or chloramines, and to identify sensitive proteins. Cells were treated with HOCl, glycine chloramine and monochloramine, reversibly oxidized cysteines were labeled and separated by 1D or 2D SDS-PAGE, and proteins were characterized by mass spectrometry. Selective protein oxidation was observed, with chloramines and HOCl causing more changes than H(2)O(2). Cyclophilin A was one of the most sensitive targets, particularly with glycine chloramine. Cyclophilin A was also oxidized in Jurkat T cells where its identity was confirmed using a knockout cell line. The product was a mixed disulfide with glutathione, with glutathionylation at Cys-161. Glyceraldehyde-3-phosphate dehydrogenase, peroxiredoxins and cofilin were also highly sensitive to HOCl/chloramines. Cyclophilins are becoming recognized as redox regulatory proteins, and glutathionylation is an important mechanism for redox regulation. Cells lacking Cyclophilin A showed more glutathionylation of other proteins than wild-type cells, suggesting that cyclophilin-regulated deglutathionylation could contribute to redox changes in HOCl/chloramine-exposed cells. Copyright © 2012 Elsevier Inc. All rights reserved.

  8. Gene expression signatures in CD34+-progenitor-derived dendritic cells exposed to the chemical contact allergen nickel sulfate

    SciTech Connect

    Schoeters, Elke . E-mail: elke.schoeters@vito.be; Nuijten, Jean-Marie; Heuvel, Rosette L. van den; Nelissen, Inge; Witters, Hilda; Schoeters, Greet E.R.; Tendeloo, Vigor F.I. van; Berneman, Zwi N.; Verheyen, Geert R.

    2006-10-01

    The detection of the sensitizing potential of chemicals is of great importance to industry. A promising in vitro alternative to the currently applied animal assays for sensitization testing makes use of dendritic cells (DCs) that have the capability to process and present antigens to naive T cells and induce their proliferation. Here, we studied changes in gene expression profiles after exposing DCs to the contact allergen nickel sulfate. CD34+-progenitor-derived DCs, initiated from 3 different donors, were exposed to 60 {mu}M nickel sulfate, during 0.5, 1, 3, 6, 12 and 24 h. cDNA microarrays were used to assess the transcriptional activity of about 11,000 genes. Significant changes in the expression of 283 genes were observed; 178 genes were up-regulated and 93 down-regulated. These genes were involved in metabolism, cell structure, immune response, transcription, signal transduction, transport, and apoptosis. No functional information was found for 74 genes. Real-time RT-PCR was used to confirm the microarray results of 12 genes. In addition, 3 DC maturation markers not present on the microarrays (DEC205, DC LAMP and CCR7) were analyzed using real-time RT-PCR and found to be up-regulated at several time points. Our data indicate that a broad range of biological processes is influenced by nickel. Some processes are clearly linked to the immune response and DC maturation, others may indicate a toxic effect of nickel.

  9. Apoptotic regulation and mutagenesis in human cells exposes to charged particles of importance for spaceflight

    NASA Astrophysics Data System (ADS)

    Kronenberg, A.; Gauny, S.; Hain, J.; Wu, P.; Wiese, C.

    Exposure to ionizing radiation can elicit two modes of cell death - necrosis or apoptosis. In human lymphoid cells, the predominant mechanism of radiation- induced cell death is apoptosis. The most likely exposure of individual human cells to heavy ions (e.g. Fe or Si) during spaceflight will result from single particle traversals. Here we report the fluence-response for apoptosis in human TK6 B- lymp hoblasts and provide evidence that single Fe ion traversals can stimulate an apoptotic response. The apoptotic response to charged particle exposures includes scrambling of the phospholipid bilayer in the cell membrane, activation of caspase signaling cascades and degradation of DNA into oligonucleosomes. We have also explored the importance of apoptotic regulation on the frequency and spectrum of mutations arising after exposure to charged particles. We used isogenic derivatives of TK6 cells stably transfected with pSFFV-neo-bcl-xL (encoding the anti-apoptotic gene BCL-XL and the neomycin resistance gene) or with pSFFV neo (encoding only- the neomycin resistance gene). TK6-bclxL cells were more susceptible to mutations at the TK1 locus than TK6-neo cells following exposure to protons, silicon ions or Fe ions. Molecular analysis demonstrated that most Fe-ion-induced mutations arose by loss of heterozygosity (LOH). In TK6-bclxL cells, more of the LOH occurred via mitotic recombination than in TK6-neo cells where the predominant mode of LOH was via deletion. We are currently mapping the LOH tracts to further define the biological bases for the differential sensitivity to Fe-ion-induced mutagenesis as a function of the genotype of the cell at risk. Supported by NASA grant T-964W to A. Kronenberg

  10. Anatase TiO2 Nanoparticles with Exposed {001} Facets for Efficient Dye-Sensitized Solar Cells

    PubMed Central

    Chu, Liang; Qin, Zhengfei; Yang, Jianping; Li, Xing’ao

    2015-01-01

    Anatase TiO2 nanoparticles with exposed {001} facets were synthesized from Ti powder via a sequential hydrothermal reaction process. At the first-step hydrothermal reaction, H-titanate nanowires were obtained in NaOH solution with Ti powder, and at second-step hydrothermal reaction, anatase TiO2 nanoparticles with exposed {001} facets were formed in NH4F solution. If the second-step hydrothermal reaction was carried out in pure water, the H-titanate nanowires were decomposed into random shape anatase-TiO2 nanostructures, as well as few impurity of H2Ti8O17 phase and rutile TiO2 phase. Then, the as-prepared TiO2 nanostructures synthesized in NH4F solution and pure water were applied to the photoanodes of dye-sensitized solar cells (DSSCs), which exhibited power conversion efficiency (PCE) of 7.06% (VOC of 0.756 V, JSC of 14.80 mA/cm2, FF of 0.631) and 3.47% (VOC of 0.764 V, JSC of 6.86 mA/cm2, FF of 0.662), respectively. The outstanding performance of DSSCs based on anatase TiO2 nanoparticles with exposed {001} facets was attributed to the high activity and large special surface area for excellent capacity of dye adsorption. PMID:26190140

  11. Anatase TiO2 Nanoparticles with Exposed {001} Facets for Efficient Dye-Sensitized Solar Cells

    NASA Astrophysics Data System (ADS)

    Chu, Liang; Qin, Zhengfei; Yang, Jianping; Li, Xing'Ao

    2015-07-01

    Anatase TiO2 nanoparticles with exposed {001} facets were synthesized from Ti powder via a sequential hydrothermal reaction process. At the first-step hydrothermal reaction, H-titanate nanowires were obtained in NaOH solution with Ti powder, and at second-step hydrothermal reaction, anatase TiO2 nanoparticles with exposed {001} facets were formed in NH4F solution. If the second-step hydrothermal reaction was carried out in pure water, the H-titanate nanowires were decomposed into random shape anatase-TiO2 nanostructures, as well as few impurity of H2Ti8O17 phase and rutile TiO2 phase. Then, the as-prepared TiO2 nanostructures synthesized in NH4F solution and pure water were applied to the photoanodes of dye-sensitized solar cells (DSSCs), which exhibited power conversion efficiency (PCE) of 7.06% (VOC of 0.756 V, JSC of 14.80 mA/cm2, FF of 0.631) and 3.47% (VOC of 0.764 V, JSC of 6.86 mA/cm2, FF of 0.662), respectively. The outstanding performance of DSSCs based on anatase TiO2 nanoparticles with exposed {001} facets was attributed to the high activity and large special surface area for excellent capacity of dye adsorption.

  12. Enhanced proliferation, attachment and osteopontin expression by porcine periodontal cells exposed to Emdogain.

    PubMed

    Rincon, J C; Xiao, Y; Young, W G; Bartold, P M

    2005-12-01

    Emdogain (EMD) is an enamel matrix derivative extracted from developing porcine teeth with demonstrated periodontal regenerative potential. EMD has been shown to influence a number of properties of periodontal ligament cells including proliferation, cell attachment and matrix synthesis. To date, the effect of EMD on the epithelial cell rests of Malassez (ERM) is unknown. In this study, periodontal ligament fibroblasts, ERM, alveolar bone cells and gingival fibroblasts were obtained from porcine periodontal ligament, alveolar bone and gingiva. This study investigated, in vitro, the effect of EMD at three concentrations on proliferation, cell attachment and expression of mRNA for two mineralised tissue-related proteins (osteopontin and bone sialoprotein). As for other periodontal cells, the ERM proliferative response was enhanced by EMD. Attachment assays revealed a highly significant increase for ERM and gingival fibroblasts after EMD treatment at all concentrations. This study has also shown that EMD stimulated expression of osteopontin mRNA by ERM and alveolar bone cells. The results from this study provide evidence that EMD enhanced cellular events related with proliferation, attachment and osteopontin mRNA expression by porcine periodontal cells, in a manner consistent with its role in periodontal regenerative therapy.

  13. Modelling induced currents in biological cells exposed to low-frequency magnetic fields.

    PubMed

    Stuchly, M A; Xi, W

    1994-09-01

    Interactions of low-frequency magnetic fields with biological systems have been a subject of intense scientific inquiry and public concern. Most research has been done at powerline frequencies of 50 Hz or 60 Hz. One of the key questions related to interactions of low-frequency magnetic fields with biological systems is which parameters of the exposure field are responsible for observed effects. Knowledge of the induced electric field and current in various experimental in vitro systems is important for this purpose. The 3D impedance method is used in this research to model spatial patterns of induced electric fields and current in two preparations of cells. A cell monolayer with a random distribution of cells and a confluent monolayer of cells with gap junctions are considered; because of the limitations of the computational method, biological cells are represented by cubes rather than more realistic shapes (e.g. spheres). The random model indicates that for higher cell densities the pattern of the induced current flow has a limited dependence on the size and shape of the container in which the cells are placed, it depends mostly on the actual cell placement. Gap junctions, not surprisingly, are shown to increase the current density, but only if their resistance is sufficiently low. The highest current density occurs in the gaps.

  14. Does tamoxifen therapy affect the hormone receptor expression and cell proliferation indices of endometrial polyps? An immunohistochemical comparison of endometrial polyps from postmenopausal women exposed and not exposed to tamoxifen.

    PubMed

    McGurgan, P; Taylor, L J; Duffy, S R; O'Donovan, P J

    2006-06-20

    This study set out to test the null hypothesis that tamoxifen therapy would not affect the hormone receptor expression (oestrogen and progesterone receptors-ER and PR) or markers of cell proliferation/apoptosis (Ki67 and Bcl-2) of endometrial polyps from postmenopausal women exposed and not exposed to tamoxifen. Endometrial polyps were prospectively obtained from women presenting with abnormal bleeding attending an out-patient hysteroscopy clinic who subsequently underwent endometrial polypectomy (16 from postmenopausal women not exposed to tamoxifen, 9 from women exposed to tamoxifen). Immunohistochemical staining for ER, PR, Ki67 and Bcl-2 was performed on polyps from both groups of women. Non-parametric statistical analysis was used (Mann-Whitney and Spearmans rank correlation). Endometrial polyps from tamoxifen users had significantly lower oestrogen receptor but increased progesterone receptor and Bcl-2 expression. There were no significant differences for proliferation markers (Ki67) between postmenopausal endometrial polyps exposed and not exposed to tamoxifen. Tamoxifen has a significant affect on hormone receptor expression and markers of apoptosis in endometrial polyps. The results support the hypothesis that tamoxifen promotes polyp growth by inhibiting apoptosis. The mechanism for this does not appear to be oestrogen receptor mediated.

  15. Reduced Neurite Density in Neuronal Cell Cultures Exposed to Serum of Patients with Bipolar Disorder

    PubMed Central

    Wollenhaupt-Aguiar, Bianca; Pfaffenseller, Bianca; Chagas, Vinicius de Saraiva; Castro, Mauro A A; Passos, Ives Cavalcante; Kauer-Sant’Anna, Márcia; Kapczinski, Flavio

    2016-01-01

    Background: Increased inflammatory markers and oxidative stress have been reported in serum among patients with bipolar disorder (BD). The aim of this study is to assess whether biochemical changes in the serum of patients induces neurotoxicity in neuronal cell cultures. Methods: We challenged the retinoic acid-differentiated human neuroblastoma SH-SY5Y cells with the serum of BD patients at early and late stages of illness and assessed neurite density and cell viability as neurotoxic endpoints. Results: Decreased neurite density was found in neurons treated with the serum of patients, mostly patients at late stages of illness. Also, neurons challenged with the serum of late-stage patients showed a significant decrease in cell viability. Conclusions: Our findings showed that the serum of patients with bipolar disorder induced a decrease in neurite density and cell viability in neuronal cultures. PMID:27207915

  16. Adhesion of Streptococcus pneumoniae to human airway epithelial cells exposed to urban particulate matter.

    PubMed

    Mushtaq, Naseem; Ezzati, Majid; Hall, Lucinda; Dickson, Iain; Kirwan, Michael; Png, Ken M Y; Mudway, Ian S; Grigg, Jonathan

    2011-05-01

    Epidemiologic studies report an association between pneumonia and urban particulate matter (PM) less than 10 microns (μm) in aerodynamic diameter (PM(10)). Streptococcus pneumoniae is a common cause of bacterial pneumonia worldwide. To date, the mechanism whereby urban PM enhances vulnerability to S pneumoniae infection is unclear. Adhesion of S pneumoniae to host cells is a prerequisite for infection. Host-expressed proteins, including the receptor for platelet-activating factor (PAFR), are co-opted by S pneumoniae to adhere to lower airway epithelial cells. To define whether inhalable urban PM enhances the adhesion of S pneumoniae to airway epithelial cells. A549 cells were cultured with PM(10) from Leicester (United Kingdom [UK]) and PM(10) and PM less than 2.5 μm in aerodynamic diameter (PM(2.5)) from Accra (Ghana), then infected with S pneumoniae strain D39. Pneumococcal adhesion to human primary bronchial epithelial cells was also assessed. Bacterial adhesion was determined by quantitative culture and confocal microscopy. The role of oxidative stress was assessed by N-acetyl cysteine, and the role of PAFR was assessed by mRNA transcript level, receptor expression, and receptor blocking. PM(10) (UK) increased S pneumoniae adhesion to both A549 airway epithelial cells and human primary bronchial epithelial cells. PM(10) (Ghana) and PM(2.5) (Ghana) also increased adhesion. Culture of A549 cells by PM(10) (UK) increased PAFR mRNA transcript level and PAFR expression. PM(10) (UK)-stimulated adhesion to A549 cells was attenuated by a PAFR blocker and N-acetyl cysteine. Urban PM increases adhesion of S pneumoniae to human airway epithelial cells. PM-stimulated adhesion is mediated by oxidative stress and PAFR. Copyright © 2011 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.

  17. Transcriptome analysis of the human T lymphocyte cell line Jurkat and human peripheral blood mononuclear cells exposed to deoxynivalenol (DON): New mechanistic insights

    SciTech Connect

    Katika, Madhumohan R.; Hendriksen, Peter J.M.; Shao, Jia; Loveren, Henk van; Peijnenburg, Ad

    2012-10-01

    Deoxynivalenol (DON) or vomitoxin is a commonly encountered type-B trichothecene mycotoxin, produced by Fusarium species predominantly found in cereals and grains. DON is known to exert toxic effects on the gastrointestinal, reproductive and neuroendocrine systems, and particularly on the immune system. Depending on dose and exposure time, it can either stimulate or suppress immune function. The main objective of this study was to obtain a deeper insight into DON-induced effects on lymphoid cells. For this, we exposed the human T-lymphocyte cell line Jurkat and human peripheral blood mononuclear cells (PBMCs) to various concentrations of DON for various times and examined gene expression changes by DNA microarray analysis. Jurkat cells were exposed to 0.25 and 0.5 μM DON for 3, 6 and 24 h. Biological interpretation of the microarray data indicated that DON affects various processes in these cells: It upregulates genes involved in ribosome structure and function, RNA/protein synthesis and processing, endoplasmic reticulum (ER) stress, calcium-mediated signaling, mitochondrial function, oxidative stress, the NFAT and NF-κB/TNF-α pathways, T cell activation and apoptosis. The effects of DON on the expression of genes involved in ER stress, NFAT activation and apoptosis were confirmed by qRT-PCR. Other biochemical experiments confirmed that DON activates calcium-dependent proteins such as calcineurin and M-calpain that are known to be involved in T cell activation and apoptosis. Induction of T cell activation was also confirmed by demonstrating that DON activates NFATC1 and induces its translocation from the cytoplasm to the nucleus. For the gene expression profiling of PBMCs, cells were exposed to 2 and 4 μM DON for 6 and 24 h. Comparison of the Jurkat microarray data with those obtained with PBMCs showed that most of the processes affected by DON in the Jurkat cell line were also affected in the PBMCs. -- Highlights: ► The human T cell line Jurkat and human

  18. Structural damage of chicken red blood cells exposed to platinum nanoparticles and cisplatin

    NASA Astrophysics Data System (ADS)

    Kutwin, Marta; Sawosz, Ewa; Jaworski, Sławomir; Kurantowicz, Natalia; Strojny, Barbara; Chwalibog, André

    2014-05-01

    Side effects and resistance of cancer cells to cisplatin are major drawbacks to its application, and recently, the possibility of replacing cisplatin with nanocompounds has been considered. Most chemotherapeutic agents are administered intravenously, and comparisons between the interactions of platinum nanoparticles (NP-Pt) and cisplatin with blood compartments are important for future applications. This study investigated structural damage, cell membrane deformation and haemolysis of chicken embryo red blood cells (RBC) after treatment with cisplatin and NP-Pt. Cisplatin (4 μg/ml) and NP-Pt (2,6 μg/ml), when incubated with chicken embryo RBC, were detrimental to cell structure and induced haemolysis. The level of haemolytic injury was increased after cisplatin and NP-Pt treatments compared to the control group. Treatment with cisplatin caused structural damage to cell membranes and the appearance of keratocytes, while NP-Pt caused cell membrane deformations (discoid shape of cells was lost) and the formation of knizocytes and echinocytes. This work demonstrated that NP-Pt have potential applications in anticancer therapy, but potential toxic side effects must be explored in future preclinical research.

  19. Structural damage of chicken red blood cells exposed to platinum nanoparticles and cisplatin.

    PubMed

    Kutwin, Marta; Sawosz, Ewa; Jaworski, Sławomir; Kurantowicz, Natalia; Strojny, Barbara; Chwalibog, André

    2014-01-01

    Side effects and resistance of cancer cells to cisplatin are major drawbacks to its application, and recently, the possibility of replacing cisplatin with nanocompounds has been considered. Most chemotherapeutic agents are administered intravenously, and comparisons between the interactions of platinum nanoparticles (NP-Pt) and cisplatin with blood compartments are important for future applications. This study investigated structural damage, cell membrane deformation and haemolysis of chicken embryo red blood cells (RBC) after treatment with cisplatin and NP-Pt. Cisplatin (4 μg/ml) and NP-Pt (2,6 μg/ml), when incubated with chicken embryo RBC, were detrimental to cell structure and induced haemolysis. The level of haemolytic injury was increased after cisplatin and NP-Pt treatments compared to the control group. Treatment with cisplatin caused structural damage to cell membranes and the appearance of keratocytes, while NP-Pt caused cell membrane deformations (discoid shape of cells was lost) and the formation of knizocytes and echinocytes. This work demonstrated that NP-Pt have potential applications in anticancer therapy, but potential toxic side effects must be explored in future preclinical research.

  20. Modulation of viability and apoptosis of UVB-exposed human keratinocyte HaCaT cells by aqueous methanol extract of laver (Porphyra yezoensis).

    PubMed

    Kim, Saerong; You, Dong Hun; Han, Taejun; Choi, Eun-Mi

    2014-12-01

    We investigated the effect of 80% methanol extract of laver (Porphyra yezoensis) on the UVB-exposed HaCaT cells, human keratinocytes. The laver extract showed absorbance spectrum characteristic of porphyra-334 or shinorine, major mycosporine-like amino acids (MAAs) in red algae, and contained phenolic compounds. UVB exposure decreased cell viability and increased apoptotic cell fractions, and it also decreased the ratio of reduced (GSH) to oxidized glutathione (GSSG) and the total glutathione content. Post-treatment with the laver extract significantly increased the net viability and also the apoptotic cell fractions of UVB-exposed cells. The extract caused increase in GSH/GSSG ratio, yet it exacerbated the decrease in glutathione content in the UVB-exposed cells. These effects of the laver extract were also manifested in the sham-exposed cells, suggesting that those effects might be general phenomena caused by the laver extract. The extract treatment enhanced the UVB-induced phosphorylation of JNK and ERK, affecting more the latter. Our results suggest that the post-treatment with laver extract may protect UVB-exposed skin cells not only by increasing overall cell proliferation but also by enhancing apoptosis of damaged cells, via activating JNK and ERK signaling pathways, in which modulation of the content and redox status of glutathione may take significant parts.

  1. Potentially-lethal damage and radioprotection in human cells exposed to californium-252

    SciTech Connect

    Schroy, C.B.; Goud, S.N.; Magura, C.; Feola, J.M.; Maruyama, Y.

    1986-01-01

    Cultured human T-1E cells were irradiated with californium-252 neutrons and gamma rays. When 2 mm caffeine was present in the medium for 47 h after irradiation cell survival (assayed by colony formation) was decreased significantly. When 2 m dimethylsulfoxide was present during the irradiations radioprotection was observed using the same assay. The caffeine data indicate that potentially-lethal lesions exist in cells after californium exposure and that these lesions can be made lethal when they would otherwise be repaired. The DMSO data indicate that radioprotection from californium exposure can be achieved and that scanvengable free radicals play an important role in Cf-252 lethality.

  2. Effects of laser-exposed gold nanorods on biochemical pathways of neuronal cells

    NASA Astrophysics Data System (ADS)

    Paviolo, Chiara; Haycock, John W.; Stoddart, Paul R.; McArthur, Sally L.

    2013-12-01

    Gold nanorods with citrate termination, poly(4 - styrenesulfonic acid) coating and silica coating were taken up by NG108 - K15 neuronal cells. This process proved to generate reactive oxygen species (ROS) and activate the nuclear factor κ -B (NF - κB). However, subsequent exposure to laser light at the plasmon resonance wavelength showed no long term cell damage or ROS / NF- κB activation. Interestingly, monitoring of intracellular Ca2+ signaling showed evidence of photo - generated transients without alteration of other normal cell functions. These results suggest new opportunities for peripheral nerve regeneration treatments and for infrared neural stimulation.

  3. Rcan1-1L overexpression induces mitochondrial autophagy and improves cell survival in angiotensin II-exposed cardiomyocytes

    SciTech Connect

    Duan, Hongyan; Li, Yongqiang; Yan, Lijie; Yang, Haitao; Wu, Jintao; Qian, Peng; Li, Bing; Wang, Shanling

    2015-07-01

    Mitochondrial autophagy is an important adaptive stress response and can be modulated by various key molecules. A previous study found that the regulator of calcineurin 1-1L (Rcan1-1L) may regulate mitochondrial autophagy and cause mitochondria degradation in neurocytes. However, the effect of Rcan1-1L on cardiomyocytes has not been determined. In the present study, we aimed to investigate the role of Rcan1-1L in angiotensin II (Ang II)-exposed human cardiomyocytes. Above all, Human adult cardiac myocytes (HACMs) were exposed to 200 nmol/L Ang II for 4 days. Enhanced H{sub 2}O{sub 2} production, cytochrome C release and mitochondrial permeability were observed in these cells, which were blocked by valsartan. Consistently, Ang II exposure significantly reduced cardiomyocyte viability. However, transfection of Rcan1-1L vector promoted cell viability and ameliorated the apoptosis caused by Ang II. Rcan1-1L clearly promoted mitochondrial autophagy in HACMs, with elevated autophagy protein (ATG) 5 and light chain 3 (LC3) expression. Transient mitochondrial biogenesis and reduced cytochrome C release was also induced by Rcan1-1L. Additionally, Rcan1-1L significantly inhibited calcineurin/nuclear factor of activated T cells (NFAT) signaling. We thus conclude that Rcan1-1L may play a protective role in Ang II-treated cardiomyocytes through the induction of mitochondrial autophagy, and may be an alternative method of cardiac protection. - Highlights: • Transfection of Rcan1-1L into HACMs promoted cell viability and reduced apoptosis. • Transfection of Rcan1-1L promoted mitochondrial autophagy in HACMs. • Rcan1-1L inhibited the calcineurin/nuclear factor of activated T cells signaling.

  4. Inter- and Intra-Chromosomal Aberrations in Human Cells Exposed in vitro to High and Low LET Radiations

    NASA Technical Reports Server (NTRS)

    Hada, M.; Wilkins, R.; Saganti, P. B.; Gersey, B.; Cucinotta, F. A.; Wu, H.

    2006-01-01

    Energetic heavy ions pose a health risk to astronauts in extended ISS and future Mars missions. High-LET heavy ions are particularly effective in causing various biological effects including cell inactivation, genetic mutations and cancer induction. Most of these biological endpoints are closely related to chromosomal damage, which can be utilized as a biomarker for radiation insults. Previously, we had studied chromosome aberrations in human lymphocytes and fibroblasts induced by both low- and high-LET radiation using FISH and multicolor fluorescence in situ hybridization (mFISH) techniques. In this study, we exposed human epithelial cells in vitro to gamma rays and energetic particles of varying types and energies and dose rates, and analyzed chromosomal damages using the multicolor banding in situ hybridization (mBAND) procedure. Confluent human epithelial cells (CH184B5F5/M10) were exposed to energetic heavy ions at NASA Space Radiation Laboratory (NSRL) at the Brookhaven National Laboratory, high energy neutron at the Los Alamos Nuclear Science Center (LANSCE) or Cs-137-gamma radiation source at the University of Texas, MD Anderson Cancer Center. After colcemid and Calyculin A treatment, cells were fixed and painted with XCyte3 mBAND kit (MetaSystems) and chromosome aberrations were analyzed with mBAND analysis system (MetaSystems). With this technique, individually painted chromosomal bands on one chromosome allowed the identification of interchromosomal aberrations (translocation to unpainted chromosomes) and intrachromosomal aberrations (inversions and deletions within a single painted chromosome). The results of the mBAND study showed a higher ratio of inversion involved with interchromosomal exchange in heavy ions compared to -ray irradiation. Analysis of chromosome aberrations using mBAND has the potential to provide useful information on human cell response to space-like radiation.

  5. Inter- and Intra-Chromosomal Aberrations in Human Cells Exposed in vitro to High and Low LET Radiations

    NASA Technical Reports Server (NTRS)

    Hada, M.; Wilkins, R.; Saganti, P. B.; Gersey, B.; Cucinotta, F. A.; Wu, H.

    2006-01-01

    Energetic heavy ions pose a health risk to astronauts in extended ISS and future Mars missions. High-LET heavy ions are particularly effective in causing various biological effects including cell inactivation, genetic mutations and cancer induction. Most of these biological endpoints are closely related to chromosomal damage, which can be utilized as a biomarker for radiation insults. Previously, we had studied chromosome aberrations in human lymphocytes and fibroblasts induced by both low- and high-LET radiation using FISH and multicolor fluorescence in situ hybridization (mFISH) techniques. In this study, we exposed human epithelial cells in vitro to gamma rays and energetic particles of varying types and energies and dose rates, and analyzed chromosomal damages using the multicolor banding in situ hybridization (mBAND) procedure. Confluent human epithelial cells (CH184B5F5/M10) were exposed to energetic heavy ions at NASA Space Radiation Laboratory (NSRL) at the Brookhaven National Laboratory, high energy neutron at the Los Alamos Nuclear Science Center (LANSCE) or Cs-137-gamma radiation source at the University of Texas, MD Anderson Cancer Center. After colcemid and Calyculin A treatment, cells were fixed and painted with XCyte3 mBAND kit (MetaSystems) and chromosome aberrations were analyzed with mBAND analysis system (MetaSystems). With this technique, individually painted chromosomal bands on one chromosome allowed the identification of interchromosomal aberrations (translocation to unpainted chromosomes) and intrachromosomal aberrations (inversions and deletions within a single painted chromosome). The results of the mBAND study showed a higher ratio of inversion involved with interchromosomal exchange in heavy ions compared to -ray irradiation. Analysis of chromosome aberrations using mBAND has the potential to provide useful information on human cell response to space-like radiation.

  6. DNA damage and apoptosis of endometrial cells cause loss of the early embryo in mice exposed to carbon disulfide

    SciTech Connect

    Zhang, Bingzhen; Shen, Chunzi; Yang, Liu; Li, Chunhui; Yi, Anji; Wang, Zhiping

    2013-12-01

    Carbon disulfide (CS{sub 2}) may lead to spontaneous abortion and very early pregnancy loss in women exposed in the workplace, but the mechanism remains unclear. We designed an animal model in which gestating Kunming strain mice were exposed to CS{sub 2} via i.p. on gestational day 4 (GD4). We found that the number of implanted blastocysts on GD8 was significantly reduced by each dose of 0.1 LD{sub 50} (157.85 mg/kg), 0.2 LD{sub 50} (315.7 mg/kg) and 0.4 LD{sub 50} (631.4 mg/kg). In addition, both the level of DNA damage and apoptosis rates of endometrial cells on GD4.5 were increased, showed definite dose–response relationships, and inversely related to the number of implanted blastocysts. The expressions of mRNA and protein for the Bax and caspase-3 genes in the uterine tissues on GD4.5 were up-regulated, while the expressions of mRNA and protein for the Bcl-2 gene were dose-dependently down-regulated. Our results indicated that DNA damage and apoptosis of endometrial cells were important reasons for the loss of implanted blastocysts induced by CS{sub 2}. - Highlights: • We built an animal model of CS2 exposure during blastocyst implantation. • Endometrial cells were used in the comet assay to detect DNA damage. • CS2 exposure caused DNA damage and endometrial cell apoptosis. • DNA damage and endometrial cell apoptosis were responsible for embryo loss.

  7. Nitric oxide measurements in hTERT-RPE cells and subcellular fractions exposed to low levels of red light

    NASA Astrophysics Data System (ADS)

    Wigle, Jeffrey C.; Castellanos, Cherry C.; Denton, Michael L.; Holwitt, Eric A.

    2014-02-01

    Cells in a tissue culture model for laser eye injury exhibit increased resistance to a lethal pulse of 2.0-μm laser radiation if the cells are first exposed to 2.88 J/cm2 of red light 24 hr prior to the lethal laser exposure. Changes in expression of various genes associated with apoptosis have been observed, but the biochemical link between light absorption and gene expression remains unknown. Cytochome c oxidase (CCOX), in the electron transport chain, is the currentlyhypothesized absorber. Absorption of the red light by CCOX is thought to facilitate displacement of nitric oxide (NO) by O2 in the active site, increasing cellular respiration and intracellular ATP. However, NO is also an important regulator and mediator of numerous physiological processes in a variety of cell and tissue types that is synthesized from l-arginine by NO synthases. In an effort to determine the relative NO contributions from these competing pathways, we measured NO levels in whole cells and subcellular fractions, with and without exposure to red light, using DAF-FM, a fluorescent dye that stoichiometrically reacts with NO. Red light induced a small, but consistently reproducible, increase in fluorescence intensity in whole cells and some subcellular fractions. Whole cells exhibited the highest overall fluorescence intensity followed by (in order) cytosolic proteins, microsomes, then nuclei and mitochondria.

  8. HSP70 expression in human trophoblast cells exposed to different 1.8 Ghz mobile phone signals.

    PubMed

    Franzellitti, Silvia; Valbonesi, Paola; Contin, Andrea; Biondi, Carla; Fabbri, Elena

    2008-10-01

    The heat-shock proteins (HSPs) are important cellular stress markers and have been proposed as candidates to infer biological effects of high-frequency electromagnetic fields (EMFs). In the current study, HSP70 gene and protein expression were evaluated in cells of the human trophoblast cell line HTR-8/SVneo after prolonged exposure (4 to 24 h) to 1.8 GHz continuous-wave (CW) and different GSM signals (GSM-217Hz and GSM-Talk) to assess the possible effects of time and modulation schemes on cell responses. Inducible HSP70 protein expression was not modified by high-frequency EMFs under any condition tested. The inducible HSP70A, HSP70B and the constitutive HSC70 transcripts did not change in cells exposed to high-frequency EMFs with the different modulation schemes. Instead, levels of the inducible HSP70C transcript were significantly enhanced after 24 h exposure to GSM-217Hz signals and reduced after 4 and 16 h exposure to GSM-Talk signals. As in other cell systems, in HTR-8/SVneo cells the response to high-frequency EMFs was detected at the mRNA level after exposure to amplitude-modulated GSM signals. The present results suggest that the expression analysis for multiple transcripts, though encoding the same or similar protein products, can be highly informative and may account for subtle changes not detected at the protein level.

  9. Transcriptomic and metabolomic approaches to investigate the molecular responses of human cell lines exposed to the flame retardant hexabromocyclododecane (HBCD).

    PubMed

    Zhang, Jinkang; Williams, Timothy D; Abdallah, Mohamed Abou-Elwafa; Harrad, Stuart; Chipman, James K; Viant, Mark R

    2015-12-01

    The potential for human exposure to the brominated flame retardant, hexabromocyclododecane (HBCD) has given rise to health concerns, yet there is relatively limited knowledge about its possible toxic effects and the underlying molecular mechanisms that may mediate any impacts on health. In this study, unbiased transcriptomic and metabolomic approaches were employed to investigate the potential molecular changes that could lead to the toxicity of HBCD under concentrations relevant to human exposure conditions using in vitro models. A concentration-dependent cytotoxic effect of HBCD to A549 and HepG2/C3A cells was observed based on MTT assays or CCK-8 assays with EC50 values of 27.4 μM and 63.0 μM, respectively. Microarray-based transcriptomics and mass spectrometry-based metabolomics revealed few molecular changes in A549 cells or HepG2/C3A cells following a 24-hour exposure to several sub-lethal concentrations (2 to 4000 nM) of HBCD. Quantification of the level of HBCD in the HepG2/C3A exposed cells suggested that the flame retardant was present at concentrations several orders of magnitude higher than those reported to occur in human tissues. We conclude that at the concentrations known to be achievable following exposure in humans, HBCD exhibits no detectable acute toxicity in A549 cells, representative of the lung, or in HepG2/C3A cells, that are hepatocytes with some xenobiotic metabolic capacity.

  10. Increased frequency of circulating Tc22/Th22 cells and polyfunctional CD38− T cells in HIV-exposed uninfected subjects

    PubMed Central

    Oliveira, Luanda M. S.; Lima, Josenilson F.; Cervantes, Cesar A. C.; S. Casseb, Jorge; Mendonça, Marcelo; Duarte, Alberto J. S.; Sato, Maria N.

    2015-01-01

    Some individuals are resistant to HIV-1 infection despite repeated exposure to the virus, suggesting the presence of a complex antiviral response. Innate factors like IL-22 exert gut mucosal protection and polyfunctional T cells have been associated with low progression in HIV infection; therefore, we evaluated the frequencies of CD4+ and CD8+ T cell-secreting cytokines, including Tc22/Th22 cells and polyfunctional T cells in HIV-1-exposed uninfected individuals (EUs), their HIV-1-infected partners and healthy controls. EUs exhibited an increased frequency of p15 Gag CD4+ IL-22+ secreting T cells, whereas HIV-infected partners demonstrated a high frequency of CD4+ IL-17+ T cells in response to p24. Similar responses of Th22 and Tc22 cells to Gag peptides and Staphylococcal enterotoxin B (SEB) stimulation were detected in the serodiscordant couples. However, polyfunctionality in HIV subjects was associated with an HIV Gag response of CD38+ T cells, whereas polyfunctionality for EUs was induced upon SEB stimulation by CD38- T cells. EUs demonstrated the presence of Tc22/Th22 cells and polyfunctional CD38- T cells with a low activation profile. These data suggest that SEB-induced polyfunctional CD4+ and CD8+ T cells together with Tc22/Th22 cells in EU individuals can provide an immunological advantage in the response to pathogens such as HIV-1. PMID:26347358

  11. Increased frequency of circulating Tc22/Th22 cells and polyfunctional CD38(-) T cells in HIV-exposed uninfected subjects.

    PubMed

    Oliveira, Luanda M S; Lima, Josenilson F; Cervantes, Cesar A C; Casseb, Jorge S; Mendonça, Marcelo; Duarte, Alberto J S; Sato, Maria N

    2015-09-08

    Some individuals are resistant to HIV-1 infection despite repeated exposure to the virus, suggesting the presence of a complex antiviral response. Innate factors like IL-22 exert gut mucosal protection and polyfunctional T cells have been associated with low progression in HIV infection; therefore, we evaluated the frequencies of CD4+ and CD8+ T cell-secreting cytokines, including Tc22/Th22 cells and polyfunctional T cells in HIV-1-exposed uninfected individuals (EUs), their HIV-1-infected partners and healthy controls. EUs exhibited an increased frequency of p15 Gag CD4+ IL-22+ secreting T cells, whereas HIV-infected partners demonstrated a high frequency of CD4+ IL-17+ T cells in response to p24. Similar responses of Th22 and Tc22 cells to Gag peptides and Staphylococcal enterotoxin B (SEB) stimulation were detected in the serodiscordant couples. However, polyfunctionality in HIV subjects was associated with an HIV Gag response of CD38+ T cells, whereas polyfunctionality for EUs was induced upon SEB stimulation by CD38- T cells. EUs demonstrated the presence of Tc22/Th22 cells and polyfunctional CD38- T cells with a low activation profile. These data suggest that SEB-induced polyfunctional CD4+ and CD8+ T cells together with Tc22/Th22 cells in EU individuals can provide an immunological advantage in the response to pathogens such as HIV-1.

  12. Proliferation and mRNA expression of absorptive villous cell markers and mineral transporters in prolactin-exposed IEC-6 intestinal crypt cells.

    PubMed

    Teerapornpuntakit, Jarinthorn; Wongdee, Kannikar; Thongbunchoo, Jirawan; Krishnamra, Nateetip; Charoenphandhu, Narattaphol

    2012-06-01

    During pregnancy and lactation, prolactin (PRL) enhances intestinal absorption of calcium and other minerals for fetal development and milk production. Although an enhanced absorptive efficiency is believed to mainly result from the upregulation of mineral transporters in the absorptive villous cells, some other possibilities, such as PRL-enhanced crypt cell proliferation and differentiation to increase the absorptive area, have never been ruled out. Here, we investigated cell proliferation and mRNA expression of mineral absorption-related genes in the PRL-exposed IEC-6 crypt cells. As expected, the cell proliferation was not altered by PRL. Inasmuch as the mRNA expressions of villous cell markers, including dipeptidylpeptidase-4, lactase and glucose transporter-5, were not increased, PRL was not likely to enhance crypt cell differentiation into the absorptive villous cells. In contrast to the previous findings in villous cells, PRL was found to downregulate the expression of calbindin-D(9k), claudin-3 and occludin in IEC-6 crypt cells, while having no effect on transient receptor potential vanilloid family channels-5/6, plasma membrane Ca(2+)-ATPase (PMCA)-1b and Na(+)/Ca(2+) exchanger-1 expression. In conclusion, IEC-6 crypt cells did not respond to PRL by increasing proliferation or differentiation into villous cells. The present results thus supported the previous hypothesis that PRL enhanced mineral absorption predominantly by increasing transporter expression and activity in the absorptive villous cells. Copyright © 2012 John Wiley & Sons, Ltd.

  13. Monitoring Intracellular Redox Changes in Ozone-exposed airway epithelial cells

    EPA Science Inventory

    Background: The toxicity of many compounds involves oxidative injury to cells. Direct assessment of mechanistic events involved in xenobiotic-induced oxidative stress is not easily achievable. Development of genetically-encoded probes designed for monitoring intracellular redox s...

  14. Mitochondrial Dysfunction and Ca(2+) Overload in Injured Sertoli Cells Exposed to Bisphenol A.

    PubMed

    Wang, Chengmin; Qi, Suqin; Liu, Changjiang; Yang, Aixia; Fu, Wenjuan; Quan, Chao; Duan, Peng; Yu, Tingting; Yang, Kedi

    2017-03-01

    Bisphenol-A (BPA) is well known as one of endocrine-disrupting chemicals and testicular toxicant. In this present study, we determined whether BPA caused cell injury through mitochondria impairment and ROS overproduction. The cellular ROS production, mitochondrial ATP synthetase activity and Ca(2+) concentration were examined. We have found BPA caused the cellular mitochondria dysfunction and followed by cell death in Sertoli cells. Moreover cytoplasm Ca(2+) overload was also involved. Furthermore, pretreatment with N-acetyl-L-cysteine (NAC) could alleviate the damage by causing a remarkable decrease in ROS production and mitochondrial dysfunction. Collectively, our results showed that BPA exposure induced Sertoli cell apoptosis because of excessive ROS generation and mitochondrial dysfunction. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 823-831, 2017. © 2016 Wiley Periodicals, Inc.

  15. Monitoring Intracellular Redox Changes in Ozone-exposed airway epithelial cells

    EPA Science Inventory

    Background: The toxicity of many compounds involves oxidative injury to cells. Direct assessment of mechanistic events involved in xenobiotic-induced oxidative stress is not easily achievable. Development of genetically-encoded probes designed for monitoring intracellular redox s...

  16. Damage Thresholds for Cultures RPE Cells Exposed to Lasers at 532 nm and 458 nm

    DTIC Science & Technology

    2007-06-01

    in onhuman primate studies. Results of in vivo studies have hown that laser damage in the retina depends upon wave- ength, power level, and duration...laser exposure similarly to RPE cells in nonhuman primate models. Our approach was to determine threshold ED50 radiant exposures for damage over a broad...our n vitro system 160 MP/cell responds in a fundamentally imilar fashion to 532-nm laser irradiation, as does the non- uman primate retina

  17. Antimutagenicity of WR-1065 in L5178Y cells exposed to accelerated (56)Fe ions

    NASA Technical Reports Server (NTRS)

    Evans, H. H.; Evans, T. E.; Horng, M. F.

    2002-01-01

    The ability of the aminothiol WR-1065 [N-(2-mercaptoethyl)-1,3-diaminopropane] to protect L5178Y (LY) cells against the cytotoxic and mutagenic effects of exposure to accelerated (56)Fe ions (1.08 GeV/nucleon) was determined. It was found that while WR-1065 reduced the mutagenicity in both cell lines when it was present during the irradiation, the addition of WR-1065 after the exposure had no effect on the mutagenicity of the radiation in either cell line. No marked protection against the cytotoxic effects of exposure to (56)Fe ions was provided by WR-1065 when added either during or after irradiation in either cell line. We reported previously that WR-1065 protected the LY-S1 and LY-SR1 cell lines against both the cytotoxicity and mutagenicity of X radiation when present during exposure, but that its protection when administered after exposure was limited to the mutagenic effects in the radiation-hypersensitive cell line, LY-S1. The results indicate that the mechanisms involved differ in the protection against cytotoxic compared to mutagenic effects and in the protection against damage caused by accelerated (56)Fe ions compared to X radiation.

  18. Influence of shear stress and size on viability of endothelial cells exposed to gold nanoparticles

    NASA Astrophysics Data System (ADS)

    Fede, C.; Albertin, Giovanna; Petrelli, L.; De Caro, R.; Fortunati, I.; Weber, V.; Ferrante, Camilla

    2017-09-01

    Screening nanoparticle toxicity directly on cell culture can be a fast and cheap technique. Nevertheless, to obtain results in accordance with those observed in live animals, the conditions in which cells are cultivated should resemble the one encountered in live systems. Microfluidic devices offer the possibility to satisfy this requirement, in particular with endothelial cell lines, because they are capable to reproduce the flowing media and shear stress experienced by these cell lines in vivo. In this work, we exploit a microfluidic device to observe how human umbilical vein endothelial cells (HUVEC) viability changes when subject to a continuous flow of culture medium, in which spherical citrate-stabilized gold nanoparticles of different sizes and at varying doses are investigated. For comparison, the same experiments are also run in multiwells where the cells do not experience the shear stress induced by the flowing medium. We discuss the results considering the influence of mode of exposure and nanoparticle size (24 and 13 nm). We observed that gold nanoparticles show a lower toxicity under flow conditions with respect to static and the HUVEC viability decreases as the nanoparticle surface area per unit volume increases, regardless of size.

  19. Distinct gene expression profiles in immortalized human urothelial cells exposed to inorganic arsenite and its methylated trivalent metabolites.

    PubMed

    Su, Pei-Fen; Hu, Yu-Jie; Ho, I-Ching; Cheng, Yang-Ming; Lee, Te-Chang

    2006-03-01

    Inorganic arsenic is an environmental carcinogen. The generation of toxic trivalent methylated metabolites complicates the study of arsenic-mediated carcinogenesis. This study systematically evaluated the effect of chronic treatment with sodium arsenite (iAs(III)), monomethylarsonous acid (MMA(III)), and dimethylarsinous acid (DMA(III)) on immortalized human uroepithelial cells (SV-HUC-1 cells) using cDNA microarray. After exposure for 25 passages to iAs(III) (0.5 microM), MMA(III) (0.05, 0.1, or 0.2 microM), or DMA(III) (0.2 or 0.5 microM), significant compound-specific morphologic changes were observed. A set of 114 genes (5.7% of the examined genes) was differentially expressed in one or more sets of arsenical-treated cells compared with untreated controls. Expression analysis showed that exposure of cells to DMA(III) resulted in a gene profile different from that in cells exposed to iAs(III) or MMA(III), and that the iAs(III)-induced gene profile was closest to that in the tumorigenic HUC-1-derived 3-methylcholanthrene-induced tumorigenic cell line MC-SV-HUC T2, which was derived from SV-HUC-1 cells by methylcholanthrene treatment. Of the genes affected by all three arsenicals, only one, that coding for interleukin-1 receptor, type II, showed enhanced expression, a finding confirmed by the reduced increase in NF-kappaB (nuclear factor kappa B) activity seen in response to interleukin-1beta in iAs(III)-exposed cells. The expression of 11 genes was suppressed by all three arsenicals. 5-Aza-deoxycytidine partially restored the transcription of several suppressed genes, showing that epigenetic DNA methylation was probably involved in arsenical-induced gene repression. Our data demonstrate that chronic exposure to iAs(III), MMA(III), or DMA(III) has different epigenetic effects on urothelial cells and represses NF-kappaB activity.

  20. Beneficial effect of Lisosan G on cultured human microvascular endothelial cells exposed to oxidised low density lipoprotein

    PubMed Central

    Lubrano, Valter; Baldi, Simona; Napoli, Debora; Longo, Vincenzo

    2012-01-01

    Background & objectives: Nutritional compounds which display anti-inflammatory and antioxidant effects have specific applications in preventing oxidative stress and endothelial dysfunction. In this study we evaluated the effect of Lisosan G (powder of Triticum sativum grains) on human microvascular endothelial cells (HMEC-1) exposed to oxidized low density lipoprotein (ox-LDL). Methods: The protective effects of Lisosan G were evaluated on human microvascular endothelial cells exposed to ox-LDL. Intercellular adhesion molecular-1 (ICAM-1), endothelin-1 (ET-1), and interleukin-6 (IL-6) concentrations and the expression of the respective genes were evaluated in response to incubation with ox-LDL, after co-incubation with ox-LDL and Lisosan G or exposed to Lisosan G alone. The analysis of LOX-1 gene was performed with RT-PCR semi quantitative method. The degree of oxidation induced in relation to control, was established by measurement of malondialdehyde (MDA) production. Results: The incubation with ox-LDL induced a significant increase in ICAM-1, IL-6 and ET-1 levels compared to the basal condition (P<0.01, P<0.05, and P<0.01, respectively), while in presence of Lisosan G, ICAM-1 levels showed a significant reduction both compared to the cultures treated with ox-LDL and control (P<0.01). IL-6 levels did not show any difference; ET-1 levels showed a partial reduction after co-treatment with Lisosan G, and also with Lisosan G alone, reduced the concentration below control (P<0.01). The modulation of these markers was confirmed by RT-PCR analysis. An association between MDA formation and the three markers production was observed. Semi-quantitative analysis of LOX-1 gene expression showed a significant up-regulation only after ox-LDL exposure. Interpretation & conclusions: The results demonstrate that Lisosan G may have an important role in the prevention of microcirculatory dysfunction. PMID:22885268

  1. Induction of anchorage-independent growth in primary human cells exposed to protons or HZE ions separately or in dual exposures.

    PubMed

    Sutherland, B M; Cuomo, N C; Bennett, P V

    2005-10-01

    Travelers on space missions will be exposed to a complex radiation environment that includes protons and heavy charged particles. Since protons are present at much higher levels than are heavy ions, the most likely scenario for cellular radiation exposure will be proton exposure followed by a hit by a heavy ion. Although the effects of individual ion species on human cells are being investigated extensively, little is known about the effects of exposure to both radiation types. One useful measure of mammalian cell damage is induction of the ability to grow in a semi-solid agar medium highly inhibitory to the growth of normal human cells, termed neoplastic transformation. Using primary human cells, we evaluated induction of soft-agar growth and survival of cells exposed to protons only or to heavy charged particles (600 MeV/nucleon silicon) only as well as of cells exposed to protons followed after a 4-day interval by silicon ions. Both ions alone efficiently transformed the human cells to anchorage-independent growth. Initial experiments indicate that the dose responses for neoplastic transformation of cells exposed to protons and then after 4 days to silicon ions appear similar to that of cells exposed to silicon ions alone.

  2. Apolipoprotein E4 Suppresses Neuronal-Specific Gene Expression in Maturing Neuronal Progenitor Cells Exposed to HIV.

    PubMed

    Geffin, Rebeca; Martinez, Ricardo; de Las Pozas, Alicia; Issac, Biju; McCarthy, Micheline

    2017-09-01

    The apolipoprotein ε4 gene allele and the apolipoprotein E4 protein (ApoE4) are important host susceptibility factors linked to neurocognitive disorders associated with HIV infection or Alzheimer's disease. Our previous studies showed differential effects of the two most common human ApoE genotypes, APOE3/3 and APOE3/4, on gene expression by differentiating human neuroepithelial progenitor cells continuously exposed to HIV. To investigate the effects of ApoE3 versus ApoE4 isoforms specifically on maturing neurons, we adapted a human neuronal progenitor cell line, hNP1, with ApoE genotype APOE3/3. Differentiating hNP1 cells were exposed for 16 days to HIV- or mock-infected supernatants and to added recombinant ApoE isoforms rApoE3 or rApoE4 to modulate the ApoE phenotype of the cells. Gene expression was investigated using microarray and functional genomics analyses. Added rApoE3 differentially affected 36 genes. Added rApoE4 differentially affected 85 genes; 41 of which were differentially expressed only in HIV or mock-supernatant treated cells, and 80% of which were downregulated. Genes differentially downregulated only by rApoE4 represented multiple neuronal functions related to neurogenesis. Approximately five times more genes were differentially enriched by rApoE4 versus rApoE3 in the Gene Ontology (GO) cellular process analysis, with 4 orders of magnitude greater significance. Half of the top 10 GO processes affected by rApoE4 treatment were neurogenesis-related. The largest differences in gene expression between the two isoforms were observed within the HIV-exposed cultures, suggesting that HIV exposure magnifies ApoE4's suppressive effect on neuronal gene expression. This study provides evidence for neuronal-specific responses to ApoE4 that could affect neurogenesis and neuronal survival.

  3. Lack of Genomic Instability in Bone Marrow Cells of SCID Mice Exposed Whole-Body to Low-Dose Radiation

    PubMed Central

    Rithidech, Kanokporn Noy; Udomtanakunchai, Chatchanok; Honikel, Louise; Whorton, Elbert

    2013-01-01

    It is clear that high-dose radiation is harmful. However, despite extensive research, assessment of potential health-risks associated with exposure to low-dose radiation (at doses below or equal to 0.1 Gy) is still challenging. Recently, we reported that 0.05 Gy of 137Cs gamma rays (the existing limit for radiation-exposure in the workplace) was incapable of inducing significant in vivo genomic instability (measured by the presence of late-occurring chromosomal damage at 6 months post-irradiation) in bone marrow (BM) cells of two mouse strains, one with constitutively high and one with intermediate levels of the repair enzyme DNA-dependent protein-kinase catalytic-subunit (DNA-PKcs). In this study, we present evidence for a lack of genomic instability in BM cells of the severely combined-immunodeficiency (SCID/J) mouse (which has an extremely low-level of DNA-PKcs activity) exposed whole-body to low-dose radiation (0.05 Gy). Together with our previous report, the data indicate that low-dose radiation (0.05 Gy) is incapable of inducing genomic instability in vivo (regardless of the levels of DNA-PKcs activity of the exposed mice), yet higher doses of radiation (0.1 and 1 Gy) do induce genomic instability in mice with intermediate and extremely low-levels of DNA-PKcs activity (indicating an important role of DNA-PKcs in DNA repair). PMID:23549227

  4. DNA damage, cell kinetics and ODC activities studied in CBA mice exposed to electromagnetic fields generated by transmission lines.

    PubMed

    Svedenstål, B M; Johanson, K J; Mattsson, M O; Paulsson, L E

    1999-01-01

    CBA mice were exposed outdoors to 50 Hz electromagnetic fields (EMF), with a flux density of about 8 microT rms (root mean square), generated by a 220 kV transmission line. Assays were performed in order to investigate, the possible genotoxic effects after 11, 20 and 32 days of exposure, as well as the effects on body weight, leukocytes, erythrocytes, and the level of ornithine decarboxylase (ODC) activity in spleen and testis. DNA migration was studied on brain cells by single cell electrophoresis (comet assay). After 32 days of exposure a highly significant change of the tail/head ratio of the comets was observed (p < 0.001), showing DNA-damage. Further, a decreased number of mononuclear leukocytes (0.02 < p < 0.05) was observed in mice EMF-exposed for 20 days. In summary, our data indicate that transmission lines of this type may induce genotoxic effects in mice, seen as changes in the DNA migration. These results might have an important implication for health effects.

  5. Interferon-α curbs production of interleukin-22 by human peripheral blood mononuclear cells exposed to live Borrelia burgdorferi.

    PubMed

    Berner, Anika; Bachmann, Malte; Pfeilschifter, Josef; Kraiczy, Peter; Mühl, Heiko

    2015-10-01

    Cytokine networks initiated by means of innate immunity are regarded as a major determinant of host defence in response to acute infection by bacteria including Borrelia burgdorferi. Herein, we demonstrate that interferon (IFN)-α, either endogenously produced after exposure of cells to toll-like receptor-9-activating CpG oligonucleotides or provided as recombinant cytokine, weakens activation of the anti-bacterial interleukin (IL)-1/IL-22 axis in human peripheral blood mononuclear cells exposed to viable B. burgdorferi. As IFN-α has been related to pathological dissemination of the spirochaete, data suggest an immunoregulatory role of type I IFN in this context that is able to significantly modify cytokine profiles thereby possibly determining early course of B. burgdorferi infection.

  6. UV-specific p53 and PTCH mutations in sporadic basal cell carcinoma of sun-exposed skin.

    PubMed

    Ratner, D; Peacocke, M; Zhang, H; Ping, X L; Tsou, H C

    2001-02-01

    UVB irradiation is known to produce DNA damage at mutation hotspots in the p53 tumor suppressor gene, leading to the development of skin cancers. Mutations in the PTCH tumor suppressor gene, which is known to be responsible for the development of nevoid basal cell carcinoma syndrome, have also been identified in sporadic basal cell carcinomas (BCCs). We describe the case of an 80-year-old welder in whom 3 novel p53 mutations, as well as UV-specific PTCH mutations, were detected in two BCC samples from sun-exposed skin. The simultaneous presence of UV-specific p53 and PTCH mutations in the same BCC sample has not previously been reported.

  7. Nuclear microprobe analysis of iodine and iron distributions in tumor cells exposed to the anthracycline 4'-iodo-4'-deoxydoxorubicin

    NASA Astrophysics Data System (ADS)

    Ortega, R.; Moretto, Ph.; Llabador, Y.; Simonoff, M.

    1997-07-01

    In this study, we performed nuclear microprobe analysis on cultured human ovarian cancer cells exposed to pharmacological concentrations of 4'-iodo-4'-deoxydoxorubicin (IDX), an anthracycline anticancer drug. We observed that iodine and iron cellular distributions were strongly correlated, suggesting intracellular iron chelation by the anthracycline. The average cellular iron concentration did not change during drug exposure, but the cellular distribution of iron was modified following the preferential nuclear localization of iodine, as determined by single cell microanalysis. These results are important for understanding the cellular pharmacology of anthracyclines. They suggest that iron cellular delocalization and its subsequent nuclear accumulation may participate to the overall cytotoxicity of IDX, and more generally to anthracycline antitumor activity.

  8. N-acetyl Glucosamine Distribution and Mitochondrial Activity of Tumor Cell Exposed to Photodynamic Therapy.

    PubMed

    Pinto, G P; Lopes, K A R; Salles, N G; Pacheco-Soares, C

    2016-11-01

    The use of lectins can play an important role for tracking modification on cell surface components, since lectins can be easily complexed with radioisotopes, biotin or fluorescein, facilitating the evaluation of carbohydrates distribution in the cell and mitochondrial activity. The aim of this study was to evaluate photodynamic therapy effects on indirect distribution of N-acetyl-glucosamine terminal glycoproteins, in human laryngeal carcinoma HEp-2 cell line surface, using lectin wheat germ agglutinin (WGA) and on mitochondrial activity, for the same cell line, using MitoTracker. The photosensitizer Aluminum Phthalocyanine Tetrasulfonate (AlPcS4) was administrated at 10 μM/mL, followed by an incubation period for its accumulation in the tumor cells, which were irradiated with laser diode λ = 685 nm and energy density of 4.5 J/cm(2). Our results indicated that, after Photodynamic Therapy (PDT), it was observed N-acetyl glucosamine terminal glycoprotein expression and mitochondrial O2 production, compared to the control group. Based on these results, we suggest that PDT influences the O2 mitochondrial production and the presence of surface glycoproteins N-acetyl glucosamine terminals.

  9. System for exposing cultured cells to intermittent hypoxia utilizing gas permeable cultureware.

    PubMed

    Polak, Jan; Studer-Rabeler, Karen; McHugh, Holly; Hussain, Mehboob A; Shimoda, Larissa A

    2015-07-01

    Tissue intermittent hypoxia (IH) occurs in obstructive sleep apnea, sickle cell anemia, physical exercise and other conditions. Poor gas solubility and slow diffusion through culture media hampers mimicking IH-induced transitions of O(2) in vitro. We aimed to develop a system enabling exposure of cultured cells to IH and to validate such exposure by real-time O(2) measurements and cellular responses. Standard 24-well culture plates and plates with bottoms made from a gas permeable film were placed in a heated cabinet. Desired cycling of O(2) levels was induced using programmable solenoids to purge mixtures of 95% N(2) + 5% CO(2) or 95% O(2) + 5% CO(2). Dissolved oxygen, gas pressure, temperature, and water evaporation were measured during cycling. IH-induced cellular effects were evaluated by hypoxia inducible factor (HIF) and NF-κB luciferase reporters in HEK296 cells and by insulin secretion in rat insulinoma cells. Oxygen cycling in the cabinet was translated into identical changes of O(2) at the well bottom in gas permeable, but not in standard cultureware. Twenty-four hours of IH exposure increased HIF (112%), NF-κB (111%) and insulin secretion (44%). Described system enables reproducible and prolonged IH exposure in cultured cells while controlling for important environmental factors.

  10. Poloxamer 188 reduces normal and phosphatidylserine-exposing erythrocyte adhesion to endothelial cells in dextran solutions.

    PubMed

    Koo, Stephanie; Yang, Yang; Neu, Björn

    2013-12-01

    Abnormal red blood cell (RBC) adhesion to endothelial cells (ECs) has been correlated with vascular complications in diseases such as sickle cell anemia and diabetes. Poloxamer 188 (P188) has been clinically tested to treat vaso-occlusion. However, the underlying mechanism(s) have not been clarified, making a methodical application difficult. In this study, we investigate how and to what extent P188 reduces RBC adhesion to ECs in plasma-like solutions. RBC adhesion to ECs is studied in solutions containing dextran, which is known to induce adhesion via macromolecular depletion interaction. It is demonstrated that P188 itself does not induce adhesion of normal RBCs to ECs but significantly reduces the adhesion in solutions containing high molecular mass-dextran. In addition, it is shown that P188 can reduce the adhesion of RBCs with enhanced exposure of phosphatidylserine (PS). Measurements of the electrophoretic mobility indicate that P188 increases the local viscosity inside the electric double layer of RBCs. Based on these results this study suggests that P188 reduces macromolecular depletion interaction, via penetrating into the depletion layer. Taking into consideration that dextran mimics the effects of pro-adhesive non-adsorbing plasma proteins and macromolecules, our study therefore suggests a mechanism for the adhesion reducing effect of P188 and should thus be of potential value for a detailed understanding of how cell-cell interactions in pathological conditions can be reduced.

  11. Combined genetic and epigenetic interferences with interferon signaling expose prostate cancer cells to viral infection

    PubMed Central

    Sabo, Yosef; Bacharach, Eran; Ehrlich, Marcelo

    2016-01-01

    Interferons (IFNs) induce anti-viral programs, regulate immune responses, and exert anti-proliferative effects. To escape anti-tumorigenic effects of IFNs, malignant cells attenuate JAK/STAT signaling and expression of IFN stimulated genes (ISGs). Such attenuation may enhance the susceptibility of tumor cells to oncolytic virotherapy. Here we studied genetic and epigenetic mechanisms of interference with JAK/STAT signaling and their contribution to susceptibility of prostate cancer cells to viral infection. Bioinformatics analysis of gene-expression in cohorts of prostate cancer patients revealed genetic and epigenetic interference with the IFN program. To correlate lack of IFN signaling and susceptibility to viral infection and oncolysis; we employed LNCaP prostate cancer cells as cellular model, and the human metapneumovirus and the epizootic hemorrhagic disease virus as infectious agents. In LNCaP cells, JAK1 is silenced by bi-allelic inactivating mutations and epigenetic silencing, which also silences ISGs. Chemical inhibition of epigenetic silencing partially restored IFN-sensitivity, induced low levels of expression of selected ISGs and attenuated, but failed to block, viral infection and oncolysis. Since viral infection was not blocked by epigenetic modifiers, and these compounds may independently-induce anti-tumor effects, we propose that epigenetic modifiers and virotherapy are compatible in treatment of prostate tumors defective in JAK1 expression and IFN signaling. PMID:27366948

  12. Oxidative stress and apoptosis are induced in human endothelial cells exposed to urban particulate matter.

    PubMed

    Montiel-Dávalos, Angélica; Ibarra-Sánchez, María de Jesús; Ventura-Gallegos, José Luis; Alfaro-Moreno, Ernesto; López-Marure, Rebeca

    2010-02-01

    Correlations between exposure to particle matter (PM) with an aerodynamic diameter cells seem to play a relevant role in the responses to PM due to their participation in pro-inflammatory events. In this study we determined the effect of PM(2.5) and PM(10) from Mexico City on human endothelial cells by means of evaluating reactive oxygen species (ROS), nitric oxide (NO), NF-kappaB translocation and cell death. For this purpose we used human umbilical vein endothelial cells (HUVEC) as a model. The production of ROS was determined by the reduction of H(2)DCFDA and NO by Griess reagent. The translocation of NF-kappaB was evaluated by Electrophoretic Mobility Shift Assay (EMSA) and the cellular death by the translocation of phosphatidylserine. TNF-alpha was used as a positive control for endothelial cell activation. PM(2.5) and PM(10) induced the production of ROS (77% and 126% increase, respectively, vs. control) and NO (up to 132% and 233% increase, respectively, vs. control). PM(2.5) and PM(10) also induced the nuclear translocation of NF-kappaB. All these events were associated with apoptosis. In conclusion, the activation of HUVEC induced by PM(2.5) and PM(10) is related with an oxidative stress, suggesting that these particles may participate in the development of cardiovascular and inflammatory diseases.

  13. Sulindac Enhances the Killing of Cancer Cells Exposed to Oxidative Stress

    PubMed Central

    Marchetti, Maria; Resnick, Lionel; Gamliel, Edna; Kesaraju, Shailaja; Weissbach, Herbert; Binninger, David

    2009-01-01

    Background Sulindac is an FDA-approved non-steroidal anti-inflammatory drug (NSAID) that affects prostaglandin production by inhibiting cyclooxygenases (COX) 1 and 2. Sulindac has also been of interest for more than decade as a chemopreventive for adenomatous colorectal polyps and colon cancer. Principal Findings Pretreatment of human colon and lung cancer cells with sulindac enhances killing by an oxidizing agent such as tert-butyl hydroperoxide (TBHP) or hydrogen peroxide. This effect does not involve cyclooxygenase (COX) inhibition. However, under the conditions used, there is a significant increase in reactive oxygen species (ROS) within the cancer cells and a loss of mitochondrial membrane potential, suggesting that cell death is due to apoptosis, which was confirmed by Tunel assay. In contrast, this enhanced killing was not observed with normal lung or colon cells. Significance These results indicate that normal and cancer cells handle oxidative stress in different ways and sulindac can enhance this difference. The combination of sulindac and an oxidizing agent could have therapeutic value. PMID:19503837

  14. Detection of hypoxia by measurement of DNA damage in individual cells from spheroids and murine tumours exposed to bioreductive drugs. II. RSU 1069.

    PubMed Central

    Olive, P. L.

    1995-01-01

    The ability of the dual-function bioreductive drug, RSU 1069, to identify hypoxic cells in multicell spheroids and murine SCCVII squamous cell carcinomas was examined using the alkaline comet method. This method applies fluorescence microscopy and image analysis to measure the amount of migration of DNA from individual cells embedded in agarose and exposed to an electric field. Chinese hamster V79 spheroids, exposed for 1 h to RSU 1069, were disaggregated and individual cells were analysed for DNA damage. Following exposure to RSU 1069, aerobic cells exhibited DNA single-strand breaks while DNA interstrand cross-links were produced in hypoxic cells. Spheroids containing 40-50% radiobiologically hypoxic cells exhibited 20-30% cells with cross-links and the remainder showed only strand breaks. Similar patterns of damage were observed in SCCVII tumours growing in C3H mice exposed to 25-200 mg kg-1. Subsequent irradiation of cells in vitro greatly improved the distinction between aerobic and hypoxic cells from spheroids or SCCVII murine tumours exposed to RSU 1069, especially after treatment with low drug doses. The pattern of damage was relatively stable for at least 4 h after drug injection. Results indicate that detection of hypoxic cells in solid tumours may be practical using this agent or a prodrug, PD 144872, selected for phase I clinical testing as a hypoxic cell radiosensitiser and cytotoxin in human tumours. PMID:7880736

  15. Detection of hypoxia by measurement of DNA damage in individual cells from spheroids and murine tumours exposed to bioreductive drugs. II. RSU 1069.

    PubMed

    Olive, P L

    1995-03-01

    The ability of the dual-function bioreductive drug, RSU 1069, to identify hypoxic cells in multicell spheroids and murine SCCVII squamous cell carcinomas was examined using the alkaline comet method. This method applies fluorescence microscopy and image analysis to measure the amount of migration of DNA from individual cells embedded in agarose and exposed to an electric field. Chinese hamster V79 spheroids, exposed for 1 h to RSU 1069, were disaggregated and individual cells were analysed for DNA damage. Following exposure to RSU 1069, aerobic cells exhibited DNA single-strand breaks while DNA interstrand cross-links were produced in hypoxic cells. Spheroids containing 40-50% radiobiologically hypoxic cells exhibited 20-30% cells with cross-links and the remainder showed only strand breaks. Similar patterns of damage were observed in SCCVII tumours growing in C3H mice exposed to 25-200 mg kg-1. Subsequent irradiation of cells in vitro greatly improved the distinction between aerobic and hypoxic cells from spheroids or SCCVII murine tumours exposed to RSU 1069, especially after treatment with low drug doses. The pattern of damage was relatively stable for at least 4 h after drug injection. Results indicate that detection of hypoxic cells in solid tumours may be practical using this agent or a prodrug, PD 144872, selected for phase I clinical testing as a hypoxic cell radiosensitiser and cytotoxin in human tumours.

  16. DNA damage in bone marrow and blood cells of mice exposed to municipal sludge leachates.

    PubMed

    Tewari, Anamika; Dhawan, Alok; Gupta, Shrawan Kumar

    2006-05-01

    Leachates of municipal solid waste from unsecured disposal sites contaminate sources of potable water and affect human health. In the present study, we have used the Comet assay to evaluate the DNA damage in mice exposed to municipal sludge leachates. Ten percent leachates were prepared from municipal sludge obtained from two different disposal drains. Male Swiss albino mice were treated daily with 0.1-0.4 ml of the leachates by oral gavage for 15 days, and the DNA damage was evaluated in bone marrow and blood using Olive tail moment, % tail DNA, and tail length as measures of DNA damage. Physicochemical and metal analysis of the leachates detected the presence of cadmium, chromium, copper, nickel, lead, and zinc, as well as elevated concentrations of sulfate and nitrate. Both of the leachates produced significant dose-responsive increases in DNA damage in both mouse tissues. There were no significant differences in the responses for any of the Comet endpoints between tissues (for the same leachate sample) or between leachate samples (for the same tissue). The results of this study indicate that municipal waste leachates produce DNA damage in vivo.

  17. Inter- and Intra-Chromosomal Aberrations in Human Cells Exposed in vitro to Space-like Radiations

    NASA Technical Reports Server (NTRS)

    Hada, Megumi; Cucinotta, F. A.; Gonda, S. R.; Wu, H.

    2005-01-01

    Energetic heavy ions pose a great health risk to astronauts in extended ISS and future exploration missions. High-LET heavy ions are particularly effective in causing various biological effects, including cell inactivation, genetic mutations and cancer induction. Most of these biological endpoints are closely related to chromosomal damage, which can be utilized as a biomarker for radiation insults. Previously, we had studied chromosome aberrations in human lymphocytes and fibroblasts induced by both low- and high-LET radiation using FISH and multicolor fluorescence in situ hybridization (mFISH) techniques. In this study, we exposed human cells in vitro to gamma rays and energetic particles of varying types and energies and dose rates, and analyzed chromosomal damages using the multicolor banding in situ hybridization (mBAND) procedure. Confluent human epithelial cells and lymphocytes were exposed to energetic heavy ions at NASA Space Radiation Laboratory (NSRL) at the Brookhaven National Laboratory (Upton, NY) or Cs-137 gamma radiation source at the Baylor College (Houston, TX). After colcemid and Calyculin A treatment, cells were fixed and painted with XCyte3 mBAND kit (MetaSystems) and chromosome aberrations were analyzed with mBAND analysis system (MetaSystems). With this technique, individually painted chromosomal bands on one chromosome allowed the identification of interchromosomal aberrations (translocation to unpainted chromosomes) and intrachromosomal aberrations (inversions and deletions within a single painted chromosome). The possible relationship between the frequency of inter- and intra-chromosomal exchanges and the track structure of radiation is discussed. The work was supported by the NASA Space Radiation Health Program.

  18. Inter- and Intra-Chromosomal Aberrations in Human Cells Exposed in vitro to Space-like Radiations

    NASA Technical Reports Server (NTRS)

    Hada, Megumi; Cucinotta, F. A.; Gonda, S. R.; Wu, H.

    2005-01-01

    Energetic heavy ions pose a great health risk to astronauts in extended ISS and future exploration missions. High-LET heavy ions are particularly effective in causing various biological effects, including cell inactivation, genetic mutations and cancer induction. Most of these biological endpoints are closely related to chromosomal damage, which can be utilized as a biomarker for radiation insults. Previously, we had studied chromosome aberrations in human lymphocytes and fibroblasts induced by both low- and high-LET radiation using FISH and multicolor fluorescence in situ hybridization (mFISH) techniques. In this study, we exposed human cells in vitro to gamma rays and energetic particles of varying types and energies and dose rates, and analyzed chromosomal damages using the multicolor banding in situ hybridization (mBAND) procedure. Confluent human epithelial cells and lymphocytes were exposed to energetic heavy ions at NASA Space Radiation Laboratory (NSRL) at the Brookhaven National Laboratory (Upton, NY) or Cs-137 gamma radiation source at the Baylor College (Houston, TX). After colcemid and Calyculin A treatment, cells were fixed and painted with XCyte3 mBAND kit (MetaSystems) and chromosome aberrations were analyzed with mBAND analysis system (MetaSystems). With this technique, individually painted chromosomal bands on one chromosome allowed the identification of interchromosomal aberrations (translocation to unpainted chromosomes) and intrachromosomal aberrations (inversions and deletions within a single painted chromosome). The possible relationship between the frequency of inter- and intra-chromosomal exchanges and the track structure of radiation is discussed. The work was supported by the NASA Space Radiation Health Program.

  19. Comparison of HIV-specific CD8 T-cell responses among uninfected individuals exposed to HIV parenterally and mucosally.

    PubMed

    Makedonas, George; Bruneau, Julie; Alary, Michel; Tsoukas, Christos M; Lowndes, Catherine M; Lamothe, François; Bernard, Nicole F

    2005-02-18

    To assess the influence of route of HIV exposure on the development of HIV-specific CD8 T-cell responses in exposed, uninfected (EU) individuals. Two groups of EU exposed to virus through either sexual or intravenous contact were studied. Group I included subjects (n = 20) who had unprotected sexual contact with known HIV-infected partners and no intravenous HIV exposure; Group II included individuals (n = 27) who had shared needles with HIV-infected partners and had no sexual exposure to this virus. Between-group comparisons were made for the proportion of responders, breadth, magnitude, and specificity of HIV-specific responses. : The interferon-gamma ELISPOT assay was used to detect HIV-specific effector activity. Peripheral blood mononuclear cells (PBMC) from each subject were stimulated with a panel of HIV peptides restricted to the MHC class I alleles expressed by the individual. A similar proportion of EU tested from each group (35.0% Group I versus 22.2% Group II) recognized at least one HIV peptide. Group I and II subjects recognized HIV peptides with a similar cumulative intensity of 130 +/- 67.5 and 182.9 +/- 184.2 spot forming cells/1 x 10 PBMC, respectively, and similar magnitude per stimulatory peptide of 82.7 and 78.4 SFC/1 x 10 PBMC, respectively. The proportion of stimulatory peptides derived from HIV Gag, reverse transcriptase, Env, and Nef was not significantly different between the two EU groups. HLA-A*0201 restricted HIV epitopes immunodominant in infected individuals are rarely stimulatory in EU subjects. Both mucosal and parenteral exposure to HIV can elicit HIV-specific CD8 T-cell responses with similar characteristics.

  20. In vivo outer hair cell length changes expose the active process in the cochlea.

    PubMed

    Zha, Dingjun; Chen, Fangyi; Ramamoorthy, Sripriya; Fridberger, Anders; Choudhury, Niloy; Jacques, Steven L; Wang, Ruikang K; Nuttall, Alfred L

    2012-01-01

    Mammalian hearing is refined by amplification of the sound-evoked vibration of the cochlear partition. This amplification is at least partly due to forces produced by protein motors residing in the cylindrical body of the outer hair cell. To transmit power to the cochlear partition, it is required that the outer hair cells dynamically change their length, in addition to generating force. These length changes, which have not previously been measured in vivo, must be correctly timed with the acoustic stimulus to produce amplification. Using in vivo optical coherence tomography, we demonstrate that outer hair cells in living guinea pigs have length changes with unexpected timing and magnitudes that depend on the stimulus level in the sensitive cochlea. The level-dependent length change is a necessary condition for directly validating that power is expended by the active process presumed to underlie normal hearing.

  1. In Vivo Outer Hair Cell Length Changes Expose the Active Process in the Cochlea

    PubMed Central

    Ramamoorthy, Sripriya; Fridberger, Anders; Choudhury, Niloy; Jacques, Steven L.; Wang, Ruikang K.; Nuttall, Alfred L.

    2012-01-01

    Background Mammalian hearing is refined by amplification of the sound-evoked vibration of the cochlear partition. This amplification is at least partly due to forces produced by protein motors residing in the cylindrical body of the outer hair cell. To transmit power to the cochlear partition, it is required that the outer hair cells dynamically change their length, in addition to generating force. These length changes, which have not previously been measured in vivo, must be correctly timed with the acoustic stimulus to produce amplification. Methodology/Principal Findings Using in vivo optical coherence tomography, we demonstrate that outer hair cells in living guinea pigs have length changes with unexpected timing and magnitudes that depend on the stimulus level in the sensitive cochlea. Conclusions/Significance The level-dependent length change is a necessary condition for directly validating that power is expended by the active process presumed to underlie normal hearing. PMID:22496736

  2. Induction of Poly(ADP-ribose) Polymerase in Mouse Bone Marrow Stromal Cells Exposed to 900 MHz Radiofrequency Fields: Preliminary Observations

    PubMed Central

    He, Qina; Sun, Yulong; Zong, Lin; Tong, Jian; Cao, Yi

    2016-01-01

    Background. Several investigators have reported increased levels of poly(ADP-ribose) polymerase-1 (PARP-1), a nuclear enzyme which plays an important role in the repair of damaged DNA, in cells exposed to extremely low dose ionizing radiation which does not cause measurable DNA damage. Objective. To examine whether exposure of the cells to nonionizing radiofrequency fields (RF) is capable of increasing messenger RNA of PARP-1 and its protein levels in mouse bone marrow stromal cells (BMSCs). Methods. BMSCs were exposed to 900 MHz RF at 120 μW/cm2 power intensity for 3 hours/day for 5 days. PARP-1 mRNA and its protein levels were examined at 0, 0.5, 1, 2, 4, 6, 8, and 10 hours after exposure using RT-PCR and Western blot analyses. Sham-exposed (SH) cells and those exposed to ionizing radiation were used as unexposed and positive control cells. Results. BMSCs exposed to RF showed significantly increased expression of PARP-1 mRNA and its protein levels after exposure to RF while such changes were not observed in SH-exposed cells. Conclusion. Nonionizing RF exposure is capable of inducing PARP-1. PMID:27190989

  3. IFNγ/IL-10 co-producing cells dominate the CD4 response to malaria in highly exposed children.

    PubMed

    Jagannathan, Prasanna; Eccles-James, Ijeoma; Bowen, Katherine; Nankya, Felistas; Auma, Ann; Wamala, Samuel; Ebusu, Charles; Muhindo, Mary K; Arinaitwe, Emmanuel; Briggs, Jessica; Greenhouse, Bryan; Tappero, Jordan W; Kamya, Moses R; Dorsey, Grant; Feeney, Margaret E

    2014-01-01

    exposed children. These CD4(+) T cells may play important modulatory roles in the development of antimalarial immunity.

  4. Linalool prevents oxidative stress activated protein kinases in single UVB-exposed human skin cells.

    PubMed

    Gunaseelan, Srithar; Balupillai, Agilan; Govindasamy, Kanimozhi; Ramasamy, Karthikeyan; Muthusamy, Ganesan; Shanmugam, Mohana; Thangaiyan, Radhiga; Robert, Beaulah Mary; Prasad Nagarajan, Rajendra; Ponniresan, Veeramani Kandan; Rathinaraj, Pierson

    2017-01-01

    Ultraviolet-B radiation (285-320 nm) elicits a number of cellular signaling elements. We investigated the preventive effect of linalool, a natural monoterpene, against UVB-induced oxidative imbalance, activation of mitogen-activated protein kinase (MAPK) and nuclear factor kappa-B (NF-κB) signaling in HDFa cells. We observed that linalool treatment (30 μM) prevented acute UVB-irradiation (20 mJ/cm2) mediated loss of activities of antioxidant enzymes in HDFa cells. The comet assay results illustrate that linalool significantly prevents UVB-mediated 8-deoxy guanosine formation (oxidative DNA damage) rather than UVB-induced cyclobutane pyrimidine (CPD) formation. This might be due to its ability to prevent UVB-induced ROS formation and to restore the oxidative imbalance of cells. This has been reflected in UVB-induced overexpression of MAPK and NF-κB signaling. We observed that linalool inhibited UVB-induced phosphorylation of ERK1, JNK and p38 proteins of MAPK family. Linalool inhibited UVB-induced activation of NF-κB/p65 by activating IκBa. We further observed that UVB-induced expression of TNF-α, IL6, IL-10, MMP-2 and MMP-9 was modulated by linalool treatment in HDFa cells. Thus, linalool protects the human skin cells from the oxidative damages of UVB radiation and modulates MAPK and NF-κB signaling in HDFa cells. The present findings substantiate that linalool may act as a photoprotective agent against UVB-induced skin damages.

  5. Morphological changes among hippocampal dentate granule cells exposed to early kindling-epileptogenesis

    PubMed Central

    Singh, Shatrunjai P.; He, Xiaoping; McNamara, James O.; Danzer, Steve C.

    2013-01-01

    Temporal lobe epilepsy is associated with changes in the morphology of hippocampal dentate granule cells. These changes are evident in numerous models that are associated with substantial neuron loss and spontaneous recurrent seizures. By contrast, previous studies have shown that in the kindling model, it is possible to administer a limited number of stimulations sufficient to produce a lifelong enhanced sensitivity to stimulus evoked seizures without associated spontaneous seizures and minimal neuronal loss. Here we examined whether stimulation of the amygdala sufficient to evoke five convulsive seizures (class IV or greater on Racine’s scale) produce morphological changes similar to those observed in models of epilepsy associated with substantial cell loss. The morphology of GFP-expressing granule cells from Thy-1 GFP mice was examined either one day or one month after the last evoked seizure. Interestingly, significant reductions in dendritic spine density were evident one day after the last seizure, the magnitude of which had diminished by one month. Further, there was an increase in the thickness of the granule cell layer one day after the last evoked seizure, which was absent a month later. We also observed an increase in the area of the proximal axon, which again returned to control levels a month later. No differences in the number of basal dendrites were detected at either time point. These findings demonstrate that the early stages of kindling epileptogenesis produce transient changes in the granule cell body layer thickness, molecular layer spine density and axon proximal area, but do not produce striking rearrangements of granule cell structure. PMID:23893783

  6. Analysis of Cap-binding Proteins in Human Cells Exposed to Physiological Oxygen Conditions.

    PubMed

    Timpano, Sara; Melanson, Gaelan; Evagelou, Sonia L; Guild, Brianna D; Specker, Erin J; Uniacke, James

    2016-12-28

    Translational control is a focal point of gene regulation, especially during periods of cellular stress. Cap-dependent translation via the eIF4F complex is by far the most common pathway to initiate protein synthesis in eukaryotic cells, but stress-specific variations of this complex are now emerging. Purifying cap-binding proteins with an affinity resin composed of Agarose-linked m(7)GTP (a 5' mRNA cap analog) is a useful tool to identify factors involved in the regulation of translation initiation. Hypoxia (low oxygen) is a cellular stress encountered during fetal development and tumor progression, and is highly dependent on translation regulation. Furthermore, it was recently reported that human adult organs have a lower oxygen content (physioxia 1-9% oxygen) that is closer to hypoxia than the ambient air where cells are routinely cultured. With the ongoing characterization of a hypoxic eIF4F complex (eIF4F(H)), there is increasing interest in understanding oxygen-dependent translation initiation through the 5' mRNA cap. We have recently developed a human cell culture method to analyze cap-binding proteins that are regulated by oxygen availability. This protocol emphasizes that cell culture and lysis be performed in a hypoxia workstation to eliminate exposure to oxygen. Cells must be incubated for at least 24 hr for the liquid media to equilibrate with the atmosphere within the workstation. To avoid this limitation, pre-conditioned media (de-oxygenated) can be added to cells if shorter time points are required. Certain cap-binding proteins require interactions with a second base or can hydrolyze the m(7)GTP, therefore some cap interactors may be missed in the purification process. Agarose-linked to enzymatically resistant cap analogs may be substituted in this protocol. This method allows the user to identify novel oxygen-regulated translation factors involved in cap-dependent translation.

  7. A study of sister chromatid exchange and somatic cell mutation in hospital workers exposed to ethylene oxide.

    PubMed

    Tomkins, D J; Haines, T; Lawrence, M; Rosa, N

    1993-10-01

    To investigate the risks of exposure to ethylene oxide (EO) at current permissible levels and at past higher levels, an inception cohort of sterilizer operators and supervisors from the Central Processing Department (CPD), respiratory therapists, and engineers exposed to EO were identified at the McMaster University Medical Centre. A comparison group from Nutrition Services (NUTR) were matched with the CPD workers on the basis of sex, age, and smoking habit. The present report is based on genetic test results for the 94 CPD and matched NUTR workers only. Statistical analysis based on the mean SCE frequency in the top 5, top 10, and all cells (50 cells scored per individual) and high frequency cells (HFC) based on the 95th percentile for nonsmoking control subjects showed a direct association with current smoking but not with EO exposure. Similarly, statistical analysis of the somatic cell mutation (SCMT) variant frequencies did not demonstrate an association with EO exposure, nor with smoking. Regression analysis indicated that sex was the only other covariate that significantly affected SCE. Age was weakly associated with SCMT. A statistically significant interaction between occupational exposure and smoking habits was observed only for the mean SCE frequency of the top 5 and top 10 cells when the 11 current CPD/NUTR pairs were not included. Thus, this interaction should be interpreted with caution.

  8. Mutant quantity and quality in mammalian cells (AL) exposed to cesium-137 gamma radiation: effect of caffeine

    NASA Technical Reports Server (NTRS)

    McGuinness, S. M.; Shibuya, M. L.; Ueno, A. M.; Vannais, D. B.; Waldren, C. A.; Chatterjee, A. (Principal Investigator)

    1995-01-01

    We examined the effect of caffeine (1,3,7-trimethylxanthine) on the quantity and quality of mutations in cultured mammalian AL human-hamster hybrid cells exposed to 137Cs gamma radiation. At a dose (1.5 mg/ml for 16 h) that reduced the plating efficiency (PE) by 20%, caffeine was not itself a significant mutagen, but it increased by approximately twofold the slope of the dose-response curve for induction of S1- mutants by 137Cs gamma radiation. Molecular analysis of 235 S1- mutants using a series of DNA probes mapped to the human chromosome 11 in the AL hybrid cells revealed that 73 to 85% of the mutations in unexposed cells and in cells treated with caffeine alone, 137Cs gamma rays alone or 137Cs gamma rays plus caffeine were large deletions involving millions of base pairs of DNA. Most of these deletions were contiguous with the region of the MIC1 gene at 11p13 that encodes the S1 cell surface antigen. In other mutants that had suffered multiple marker loss, the deletions were intermittent along chromosome 11. These "complex" mutations were rare for 137Cs gamma irradiation (1/63 = 1.5%) but relatively prevalent (23-50%) for other exposure conditions. Thus caffeine appears to alter both the quantity and quality of mutations induced by 137Cs gamma irradiation.

  9. Activation of transcription factors in human bronchial epithelial cells exposed to aqueous extracts of mainstream cigarette smoke in vitro.

    PubMed

    Sekine, Takashi; Hirata, Tadashi; Mine, Toshiki; Fukano, Yasuo

    2016-01-01

    This study aimed to identify the most sensitive transcription factor activated by cigarette smoke extract (CSE) and to explore cigarette smoke components that have high biological activities in a cell-base assay. Previously, we found evidence that implicated 10 different transcription factors as having a high biological activity to CSE in vitro, based on the results of a comprehensive gene expression profile. For this study, luciferase reporter assays for each transcription factor were developed in two types of human bronchial epithelial cells: NCI-H292 and BEAS-2B cells. The results demonstrated that the nuclear factor erythroid 2-related factor 2 (NRF2)/anti-oxidant response element (ARE) pathway was the most sensitive in response to CSE. Consistently, hemo oxygenase-1 (HO-1), a downstream target gene of NRF2, was effectively up-regulated in BEAS-2B cells exposed to CSE. Moreover, among 1395 cigarette smoke components, naphthoquinones including 9,10-phenaotrenquinone, quinones, benzenediols and α, β-unsaturated carbonyls, were identified as major smoke components that contribute to activating the NRF2/ARE pathway, as indicated by the ARE-reporter assay in BEAS-2B cells. Taken together, NRF2 appears to be a key molecule in the CSE-induced cellular response, and the employed methodology is helpful for the analysis of molecular and cellular effects by CSE.

  10. Mutant quantity and quality in mammalian cells (AL) exposed to cesium-137 gamma radiation: effect of caffeine

    NASA Technical Reports Server (NTRS)

    McGuinness, S. M.; Shibuya, M. L.; Ueno, A. M.; Vannais, D. B.; Waldren, C. A.; Chatterjee, A. (Principal Investigator)

    1995-01-01

    We examined the effect of caffeine (1,3,7-trimethylxanthine) on the quantity and quality of mutations in cultured mammalian AL human-hamster hybrid cells exposed to 137Cs gamma radiation. At a dose (1.5 mg/ml for 16 h) that reduced the plating efficiency (PE) by 20%, caffeine was not itself a significant mutagen, but it increased by approximately twofold the slope of the dose-response curve for induction of S1- mutants by 137Cs gamma radiation. Molecular analysis of 235 S1- mutants using a series of DNA probes mapped to the human chromosome 11 in the AL hybrid cells revealed that 73 to 85% of the mutations in unexposed cells and in cells treated with caffeine alone, 137Cs gamma rays alone or 137Cs gamma rays plus caffeine were large deletions involving millions of base pairs of DNA. Most of these deletions were contiguous with the region of the MIC1 gene at 11p13 that encodes the S1 cell surface antigen. In other mutants that had suffered multiple marker loss, the deletions were intermittent along chromosome 11. These "complex" mutations were rare for 137Cs gamma irradiation (1/63 = 1.5%) but relatively prevalent (23-50%) for other exposure conditions. Thus caffeine appears to alter both the quantity and quality of mutations induced by 137Cs gamma irradiation.

  11. Collagen Synthesis in Tenocytes, Ligament Cells and Chondrocytes Exposed to a Combination of Glucosamine HCl and Chondroitin Sulfate

    PubMed Central

    2007-01-01

    Clinical testing of the nutraceuticals glucosamine (glcN) and chondroitin sulfate (CS) has shown efficacy in providing relief from symptoms in osteoarthritic patients. In vitro and in vivo studies support existence of a synergistic relationship upregulating synthetic activity in chondrocytes. A combination of glcN and CS may also be useful as adjunct therapy in sports-related injuries if similar upregulation of collagen synthesis is elicited in accessory ligament and tendon joint tissue. Collagen and non-collagenous protein (NCP) synthesis in cultures of bovine tenocytes, ligament cells and chondrocytes exposed to glcN + CS were assayed by uptake of radiolabeled proline into collagenase-sensitive material. Assay of radiolabel in hydroxyproline (a specific marker for collagen synthesis) following HPLC isolation confirmed the specificity of the metabolic effect. Synthesis of total collagenase-sensitive material was maximally upregulated at physiologically obtainable doses of glcN + CS. Tissue response followed the sequence ligament cells (+69%) > chondrocytes (+56%) > tenocytes (+22%). Labeled hydroxyproline increased by 132% in ligament cells, 27% in tenocytes and 49% in epitendon cells after a 48 h exposure to 5 μg ml−1 glcN + 4 μg ml−1 CS. Low dose combinations of glcN and CS effectively stimulate in vitro collagen and NCP synthesis by ligament cells, tenocytes and chondrocytes. Hence, therapeutic use following accessory joint tissue trauma may help augment repair processes. PMID:17549239

  12. In vitro measurements of oxygen consumption rates in hTERT-RPE cells exposed to low levels of red light

    NASA Astrophysics Data System (ADS)

    Wigle, Jeffrey C.; Castellanos, Cherry C.

    2016-03-01

    Exposure to 2.88 J/cm2 of red light induces an adaptive response against a lethal pulse of 2.0 μm laser radiation in hTERT-RPE cells in vitro, but not in a knockdown mutant for vascular endothelial growth factor c (VEGF-C). The generally accepted initiation sequence for photobiomodulation is that absorption of red light by cytochome c oxidase (CCOX) of the electron transport chain increases the binding affinity of CCOX for O2 vs. nitric oxide (NO). This results in displacement of NO by O2 in the active site of CCOX, thereby increasing cellular respiration and intracellular ATP. We've previously reported that red-light exposure induces a small, but consistently reproducible, increase in NO levels in these cells. But the relative importance of NO and oxidative phosphorylation is unclear because little is known about the relative contributions of NO and ATP to the response. However, if NO dissociation from CCOX actually increases oxidative phosphorylation, one should see a corresponding increase in oxygen consumption. A Seahorse Extracellular Flux Analyzer was used to measure oxygen consumption rates (OCR) in normal and mutant cells as a proxy for oxidative phosphorylation. Both basal respiration and maximum respiration rates in normal cells are significantly higher than in the mutant. The normal cells have a significant amount of "excess capacity," whereas the VEGF-C(KD) have little or none. The OCR in exposed normal cells is lower than in unexposed cells when measured immediately after exposure. The exposures used for these experiments had no effect on the OCR in mutant cells.

  13. ACTIVATION OF THE EGF RECEPTOR SIGNALING PATHWAY IN HUMAN AIRWAY EPITHELIAL CELLS EXPOSED TO METALS

    EPA Science Inventory

    We have previously shown that exposure to combustion-derived metals rapidly (within 20 min) activated mitogen-activated protein kinases (MAPK), including extracellular signal-regulated kinase (ERK), in the human bronchial epithelial cell line BEAS. To study the mechanisms respons...

  14. Nanomimics of host cell membranes block invasion and expose invasive malaria parasites.

    PubMed

    Najer, Adrian; Wu, Dalin; Bieri, Andrej; Brand, Françoise; Palivan, Cornelia G; Beck, Hans-Peter; Meier, Wolfgang

    2014-12-23

    The fight against most infectious diseases, including malaria, is often hampered by the emergence of drug resistance and lack or limited efficacies of vaccines. Therefore, new drugs, vaccines, or other strategies to control these diseases are needed. Here, we present an innovative nanotechnological strategy in which the nanostructure itself represents the active substance with no necessity to release compounds to attain therapeutic effect and which might act in a drug- and vaccine-like dual function. Invasion of Plasmodium falciparum parasites into red blood cells was selected as a biological model for the initial validation of this approach. Stable nanomimics-polymersomes presenting receptors required for parasite attachment to host cells-were designed to efficiently interrupt the life cycle of the parasite by inhibiting invasion. A simple way to build nanomimics without postformation modifications was established. First, a block copolymer of the receptor with a hydrophobic polymer was synthesized and then mixed with a polymersome-forming block copolymer. The resulting nanomimics bound parasite-derived ligands involved in the initial attachment to host cells and they efficiently blocked reinvasion of malaria parasites after their egress from host cells in vitro. They exhibited efficacies of more than 2 orders of magnitude higher than the soluble form of the receptor, which can be explained by multivalent interactions of several receptors on one nanomimic with multiple ligands on the infective parasite. In the future, our strategy might offer interesting treatment options for severe malaria or a way to modulate the immune response.

  15. Testosterone Protects Mitochondrial Function and Regulates Neuroglobin Expression in Astrocytic Cells Exposed to Glucose Deprivation

    PubMed Central

    Toro-Urrego, Nicolas; Garcia-Segura, Luis M.; Echeverria, Valentina; Barreto, George E.

    2016-01-01

    Testosterone is a hormone that has been shown to confer neuroprotection from different insults affecting the central nervous system (CNS). Testosterone induces this protection by different mechanisms that include the activation of anti-apoptotic pathways that are directly implicated in neuronal survival. However, little attention has been devoted to its actions on glial cells. In the present study, we have assessed whether testosterone exerts protection in a human astrocyte cell model, the T98G cells. Our results indicate that testosterone improves cell survival and mitochondrial membrane potential and reduces nuclear fragmentation and reactive oxygen species (ROS) generation. These effects were accompanied by a positive regulation of neuroglobin, an oxygen-binding and sensor protein, which may serve as a regulator of ROS and nitrogen reactive species (NOS), and these protective effects of testosterone may be at least in part mediated by estradiol and DHT. In conclusion, these findings suggest that astroglia may mediate some of the protective actions of testosterone in the brain upon pathological conditions. PMID:27445795

  16. GENE EXPRESSION PROFILING OF NORMAL HUMAN BRONCHIAL EPITHELIAL CELLS EXPOSED TO TRIVALENT ARSENICALS AND DIMETHYLTHIOARSINIC ACID

    EPA Science Inventory

    Lung is a major target for arsenic carcinogenesis in humans. However, the carcinogenic mode of action of arsenicals is unknown. We investigated, in human bronchial epithelial (BEAS2B) cells, the effects of inorganic arsenic (iAsIII), monomethylarsonous acid (MMAIII), dimethylarsi...

  17. GENE EXPRESSION PROFILING OF NORMAL HUMAN BRONCHIAL EPITHELIAL CELLS EXPOSED TO TRIVALENT ARSENICALS AND DIMETHYLTHIOARSINIC ACID

    EPA Science Inventory

    Lung is a major target for arsenic carcinogenesis in humans. However, the carcinogenic mode of action of arsenicals is unknown. We investigated, in human bronchial epithelial (BEAS2B) cells, the effects of inorganic arsenic (iAsIII), monomethylarsonous acid (MMAIII), dimethylarsi...

  18. ACTIVATION OF THE EGF RECEPTOR SIGNALING PATHWAY IN HUMAN AIRWAY EPITHELIAL CELLS EXPOSED TO METALS

    EPA Science Inventory

    We have previously shown that exposure to combustion-derived metals rapidly (within 20 min) activated mitogen-activated protein kinases (MAPK), including extracellular signal-regulated kinase (ERK), in the human bronchial epithelial cell line BEAS. To study the mechanisms respons...

  19. Photobiomodulation Protects and Promotes Differentiation of C2C12 Myoblast Cells Exposed to Snake Venom

    PubMed Central

    da Silva, Aline; Vieira, Rodolfo Paula; Mesquita-Ferrari, Raquel Agnelli; Cogo, José Carlos; Zamuner, Stella Regina

    2016-01-01

    Background Snakebites is a neglected disease and in Brazil is considered a serious health problem, with the majority of the snakebites caused by the genus Bothrops. Antivenom therapy and other first-aid treatments do not reverse local myonecrose which is the main sequel caused by the envenomation. Several studies have shown the effectiveness of low level laser (LLL) therapy in reducing local myonecrosis induced by Bothropic venoms, however the mechanism involved in this effect is unknown. In this in vitro study, we aimed to analyze the effect of LLL irradiation against cytotoxicity induced by Bothrops jararacussu venom on myoblast C2C12 cells. Methodology C2C12 were utilized as a model target and were incubated with B. jararacussu venom (12.5 μg/mL) and immediately irradiated with LLL at wavelength of red 685 nm or infrared 830 nm with energy density of 2.0, 4.6 and 7.0 J/cm2. Effects of LLL on cellular responses of venom-induced cytotoxicity were examined, including cell viability, measurement of cell damage and intra and extracellular ATP levels, expression of myogenic regulatory factors, as well as cellular differentiation. Results In non-irradiated cells, the venom caused a decrease in cell viability and a massive release of LDH and CK levels indicating myonecrosis. Infrared and red laser at all energy densities were able to considerably decrease venom-induced cytotoxicity. Laser irradiation induced myoblasts to differentiate into myotubes and this effect was accompanied by up regulation of MyoD and specially myogenin. Moreover, LLL was able to reduce the extracellular while increased the intracellular ATP content after venom exposure. In addition, no difference in the intensity of cytotoxicity was shown by non-irradiated and irradiated venom. Conclusion LLL irradiation caused a protective effect on C2C12 cells against the cytotoxicity caused by B. jararacussu venom and promotes differentiation of these cells by up regulation of myogenic factors. A modulatory

  20. Effects of 50 Hz magnetic field on cell cycle kinetics and the colony forming ability of budding yeast exposed to ultraviolet radiation.

    PubMed

    Markkanen, A; Juutilainen, J; Lang, S; Pelkonen, J; Rytömaa, T; Naarala, J

    2001-07-01

    To investigate the effects of extremely low frequency magnetic fields on ultraviolet radiation (UV) exposed budding yeast, haploid yeast (Saccharomyces cerevisiae) cells of the strain SEy2101a were exposed to 50 Hz sine wave magnetic field (MF) of 120 microT with simultaneous exposure to UV radiation. Most of the UV energy was in the UVB range (280-320 nm). The biologically weighted (CIE action spectrum) dose level for the UV radiation was 175 J/m2. We examined whether 50 Hz MF affected the ability of UV irradiated yeast cells to form colonies (Colony Forming Units, CFUs). In addition, the effect of coexposure on cell cycle kinetics was investigated. Although the significant effect of MF on the cell cycle phases of UV exposed yeast cells was seen only at one time point, the overall results showed that MF exposure may influence the cell cycle kinetics at the first cycle after UV irradiation. The effect of our particular MF exposure on the colony forming ability of the UV irradiated yeast cells was statistically significant 420 min after UV irradiation. Moreover, at 240, 360, and 420 min after UV irradiation, there were fewer CFUs in every experiment in (UV+MF) exposed populations than in only UV exposed yeast populations. These results could indicate that MF exposure in conjunction with UV may have some effects on yeast cell survival or growth. Copyright 2001 Wiley-Liss, Inc.

  1. Gene expression profile of human lung epithelial cells chronically exposed to single-walled carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Chen, Dongquan; Stueckle, Todd A.; Luanpitpong, Sudjit; Rojanasakul, Yon; Lu, Yongju; Wang, Liying

    2015-01-01

    A rapid increase in utility of engineered nanomaterials, including carbon nanotubes (CNTs), has raised a concern over their safety. Based on recent evidence from animal studies, pulmonary exposure of CNTs may lead to nanoparticle accumulation in the deep lung without effective clearance which could interact with local lung cells for a long period of time. Physicochemical similarities of CNTs to asbestos fibers may contribute to their asbestos-like carcinogenic potential after long-term exposure, which has not been well addressed. More studies are needed to identify and predict the carcinogenic potential and mechanisms for promoting their safe use. Our previous study reported a long-term in vitro exposure model for CNT carcinogenicity and showed that 6-month sub-chronic exposure of single-walled carbon nanotubes (SWCNT) causes malignant transformation of human lung epithelial cells. In addition, the transformed cells induced tumor formation in mice and exhibited an apoptosis resistant phenotype, a key characteristic of cancer cells. Although the potential role of p53 in the transformation process was identified, the underlying mechanisms of oncogenesis remain largely undefined. Here, we further examined the gene expression profile by using genome microarrays to profile molecular mechanisms of SWCNT oncogenesis. Based on differentially expressed genes, possible mechanisms of SWCNT-associated apoptosis resistance and oncogenesis were identified, which included activation of pAkt/p53/Bcl-2 signaling axis, increased gene expression of Ras family for cell cycle control, Dsh-mediated Notch 1, and downregulation of apoptotic genes BAX and Noxa. Activated immune responses were among the major changes of biological function. Our findings shed light on potential molecular mechanisms and signaling pathways involved in SWCNT oncogenic potential.

  2. Hyperosmolaric contrast agents in cartilage tomography may expose cartilage to overload-induced cell death.

    PubMed

    Turunen, M J; Töyräs, J; Lammi, M J; Jurvelin, J S; Korhonen, R K

    2012-02-02

    In clinical arthrographic examination, strong hypertonic contrast agents are injected directly into the joint space. This may reduce the stiffness of articular cartilage, which is further hypothesized to lead to overload-induced cell death. We investigated the cell death in articular cartilage while the tissue was compressed in situ in physiological saline solution and in full strength hypertonic X-ray contrast agent Hexabrix(TM). Samples were prepared from bovine patellae and stored in Dulbecco's Modified Eagle's Medium overnight. Further, impact tests with or without creep were conducted for the samples with contact stresses and creep times changing from 1 MPa to 10 MPa and from 0 min to 15 min, respectively. Finally, depth-dependent cell viability was assessed with a confocal microscope. In order to characterize changes in the biomechanical properties of cartilage as a result of the use of Hexabrix™, stress-relaxation tests were conducted for the samples immersed in Hexabrix™ and phosphate buffered saline (PBS). Both dynamic and equilibrium modulus of the samples immersed in Hexabrix™ were significantly (p<0.05) lower than those of the samples immersed in PBS. Cartilage samples immersed in physiological saline solution showed load-induced cell death primarily in the superficial and middle zones. However, under high 8-10 MPa contact stresses, the samples immersed in full strength Hexabrix™ showed significantly (p<0.05) higher number of dead cells than the samples compressed in physiological saline, especially in the deep zone of cartilage. In conclusion, excessive loading stresses followed by tissue creep might increase the risk for chondrocyte death in articular cartilage when immersed in hypertonic X-ray contrast agent, especially in the deep zone of cartilage.

  3. The Morphological and Molecular Changes of Brain Cells Exposed to Direct Current Electric Field Stimulation

    PubMed Central

    Pelletier, Simon J.; Lagacé, Marie; St-Amour, Isabelle; Arsenault, Dany; Cisbani, Giulia; Chabrat, Audrey; Fecteau, Shirley; Lévesque, Martin

    2015-01-01

    Background: The application of low-intensity direct current electric fields has been experimentally used in the clinic to treat a number of brain disorders, predominantly using transcranial direct current stimulation approaches. However, the cellular and molecular changes induced by such treatment remain largely unknown. Methods: Here, we tested various intensities of direct current electric fields (0, 25, 50, and 100V/m) in a well-controlled in vitro environment in order to investigate the responses of neurons, microglia, and astrocytes to this type of stimulation. This included morphological assessments of the cells, viability, as well as shape and fiber outgrowth relative to the orientation of the direct current electric field. We also undertook enzyme-linked immunosorbent assays and western immunoblotting to identify which molecular pathways were affected by direct current electric fields. Results: In response to direct current electric field, neurons developed an elongated cell body shape with neurite outgrowth that was associated with a significant increase in growth associated protein-43. Fetal midbrain dopaminergic explants grown in a collagen gel matrix also showed a reorientation of their neurites towards the cathode. BV2 microglial cells adopted distinct morphological changes with an increase in cyclooxygenase-2 expression, but these were dependent on whether they had already been activated with lipopolysaccharide. Finally, astrocytes displayed elongated cell bodies with cellular filopodia that were oriented perpendicularly to the direct current electric field. Conclusion: We show that cells of the central nervous system can respond to direct current electric fields both in terms of their morphological shape and molecular expression of certain proteins, and this in turn can help us to begin understand the mechanisms underlying the clinical benefits of direct current electric field. PMID:25522422

  4. The morphological and molecular changes of brain cells exposed to direct current electric field stimulation.

    PubMed

    Pelletier, Simon J; Lagacé, Marie; St-Amour, Isabelle; Arsenault, Dany; Cisbani, Giulia; Chabrat, Audrey; Fecteau, Shirley; Lévesque, Martin; Cicchetti, Francesca

    2014-12-07

    The application of low-intensity direct current electric fields has been experimentally used in the clinic to treat a number of brain disorders, predominantly using transcranial direct current stimulation approaches. However, the cellular and molecular changes induced by such treatment remain largely unknown. Here, we tested various intensities of direct current electric fields (0, 25, 50, and 100V/m) in a well-controlled in vitro environment in order to investigate the responses of neurons, microglia, and astrocytes to this type of stimulation. This included morphological assessments of the cells, viability, as well as shape and fiber outgrowth relative to the orientation of the direct current electric field. We also undertook enzyme-linked immunosorbent assays and western immunoblotting to identify which molecular pathways were affected by direct current electric fields. In response to direct current electric field, neurons developed an elongated cell body shape with neurite outgrowth that was associated with a significant increase in growth associated protein-43. Fetal midbrain dopaminergic explants grown in a collagen gel matrix also showed a reorientation of their neurites towards the cathode. BV2 microglial cells adopted distinct morphological changes with an increase in cyclooxygenase-2 expression, but these were dependent on whether they had already been activated with lipopolysaccharide. Finally, astrocytes displayed elongated cell bodies with cellular filopodia that were oriented perpendicularly to the direct current electric field. We show that cells of the central nervous system can respond to direct current electric fields both in terms of their morphological shape and molecular expression of certain proteins, and this in turn can help us to begin understand the mechanisms underlying the clinical benefits of direct current electric field. © The Author 2015. Published by Oxford University Press on behalf of CINP.

  5. Efficacy of human umbilical cord derived-mesenchymal stem cells in treatment of rat bone marrow exposed to gamma irradiation.

    PubMed

    Mousa, Hanaa S E; Shalaby, Sally M; Gouda, Zienab A; Ahmed, Fayza E; El-Khodary, Aisha A

    2017-03-01

    To assess the therapeutic effects of the human umbilical cord blood (hUCB) derived mesenchymal stem cells (MSCs) on rat bone marrow (BM) exposed to gamma rays, 3 groups (n=15 each) of adult male Wistar albino rats were utilized as follows: the 1st group received PBS (control group), the 2nd group was exposed to gamma rays 1.04Gy/min (R group) and the 3rd group exposed to same dose as RG and injected hUCB-MSCs. The BM of femurs was processed for histological and immunohistochemical staining with proliferating cell nuclear antigen antibody (PCNA), anti human CD105 and anti human CD34. Hb content, leukocytes and platelet counts were analyzed as well as fat cells and megakaryocytic counts. Also, the BM vascular spaces and the optical density of immunostaining for PCNA were analyzed. The leukocytes and platelet counts were significantly lower in the R (2.85±235.8; P=0.000 and 95.27±3.01; P=0.000 respectively) when compared with the control (10.40±443.2; P=0.000 and 430.18±20.28; P=0.000 respectively). The fat cell count was significantly higher in the R (36.55±1.83; P=0.000) than in control (7.64±0.61; P=0.000) and in R injected h-MSCs tissues (18.82±2.03; P=0.000). The megakaryocytic count was significantly higher in the R injected h-MSCs (5.36±0.310; P=0.000) than in control (2.82±0.263; P=0.000) and in the R BM (0.45±0.157; P=0.000). The vascular spaces were dilated and significantly increased in the R injected h-MSCs (50.10±2.40; P=0.000) than in control (33.36±1.01; P=0.000). The optical density of PCNA expression was significantly lower in R (0.18±0.11; P=0.005) than in control (0.41±0.40; P=0.005) and in R injected h-MSCs groups (0.30±0.17; P=0.005). The present study concluded that injection of hUCB-MSCs improves destructive effects of bone marrow induced by gamma radiation. Use of radio-protective agents during exposure is recommended. Copyright © 2016 Elsevier GmbH. All rights reserved.

  6. Müller cell gliotic response in the retina of the newts exposed to real and simulated microgravity

    NASA Astrophysics Data System (ADS)

    Grigoryan, Eleonora N.; Poplinskaya, Valentina; Domaratskaya; Aleinikova, Karina; Novikova, Julia; Anton, Hermann J.; Almeida, Eduardo

    The effects of real and simulated microgravity on the eye tissue regeneration of newts (Pl. waltli) after lens and/or retina removal were investigated. Changes in Müller glial cells in the retina of eyes regenerating after lens extirpation were detected in newts exposed to clinostat-ing. The cells were hypertrophied, and their processes thickened. Such changes were viewed as specific of reactive gliosis [1]. Later experiments onboard the Russian biosatellite Bion-11 showed similar changes in the retinas of newts regenerating after a two-week spaceflight. In the Bion-11 animals, GFAP, the major structural protein of macroglial cells was found to be up-regulated [2]. In more recent experiments onboard Foton-2 (2005) and Foton-M3 (2007), GFAP expression in retinas of space-flown, ground control (kept at 1 g), and basal control (sacrificed on launch day) newts was quantified, using microscopy, immunohistochemistry, and digital image analysis. It was found that Müller cell processes of non-operated animals dis-u played low GFAP immunolabeling. A low level of immunoreactivity was also observed in basal controls. In contrast, retinas of space-flown animals showed greater GFAP immunoreactivity associated with both an increased cell number and a higher density of intermediate filaments [3]. This, in turn, was accompanied by up-regulation of stress protein (HSP90) and growth factor (FGF2) expressions. It can be postulated that such a response of Müller cells was to mitigate the retinal stress in newts exposed to microgravity. Although the exact mechanisms remain unknown, it can be hypothesized that GFAP up-regulation is mediated by HSPs and growth factors, particularly by FGF2. Taken together, these data suggest that the retinal population of macroglial cells is sensitive to gravity changes and that in space it can react by enhancing its neuroprotective function. [1] Grigoryan E.N., Anton H.J., Mitashov V.I. Adv. Space Res. 1998. V. 22. N.2. P. 293-301. [2] Grigoryan E

  7. Renal Cell Carcinomas in Vinylidene Chloride Exposed Male B6C3F1 Mice Are Characterized by Oxidative Stress and TP53 Pathway Dysregulation

    PubMed Central

    Hayes, Schantel A.; Pandiri, Arun R.; Ton, Thai-vu T.; Hong, Hue-Hua L.; Clayton, Natasha P.; Shockley, Keith R.; Peddada, Shyamal D.; Gerrish, Kevin; Wyde, Michael; Sills, Robert C.; Hoenerhoff, Mark J.

    2015-01-01

    Vinylidene Chloride (VDC) has been widely used in the production of plastics and flame retardants. Exposure of B6C3F1 mice to VDC in the 2-year National Toxicology Program carcinogenicity bioassay resulted in a dose-dependent increases in renal cell hyperplasia, adenoma, and carcinoma (RCCs). Among those differentially expressed genes between controls and RCC from VDC-exposed mice, there was an overrepresentation of genes from pathways associated with chronic xenobiotic and oxidative stress, as well as c-Myc overexpression and dysregulation of TP53 cell cycle checkpoint and DNA damage repair pathways in RCC. Trend analysis comparing RCC, VDC-exposed kidney, and chamber control kidney showed a conservation of pathway dysregulation in terms of overrepresentation of xenobiotic and oxidative stress, and DNA damage and cell cycle checkpoint pathways in both VDC-exposed kidney and RCC, suggesting that these mechanisms play a role in the pathogenesis of RCC in VDC-exposed mice. PMID:26682919

  8. DNA Repair in Human Cells Exposed to Combinations of Carcinogenic Agents

    SciTech Connect

    Setlow, R. B.; Ahmed, F. E.

    1980-01-01

    Normal human and XP2 fibroblasts were treated with UV plus UV-mimetic chemicals. The UV dose used was sufficient to saturate the UV excision repair system. Excision repair after combined treatments was estimated by unscheduled DNA synthesis, BrdUrd photolysis, and the loss of sites sensitive to a UV specific endonuclease. Since the repair of damage from UV and its mimetics is coordinately controlled we expected that there would be similar rate-limiting steps in the repair of UV and chemical damage and that after a combined treatment the total amount of repair would be the same as from UV or the chemicals separately. The expectation was not fulfilled. In normal cells repair after a combined treatment was additive whereas in XP cells repair after a combined treatment was usually less than after either agent separately. The chemicals tested were AAAF, DMBA-epoxide, 4NQO, and ICR-170.

  9. Study on cytotoxicity and structure-activity relationship of HL-7702 cell exposed to naphthoquinones.

    PubMed

    Guo, Jing; Song, Wenhua; Ding, Feng; Zhang, Jinyang; Sun, Zengtian

    2012-05-01

    The acute cytotoxicities of six naphthoquinone compounds, including Atovaquone, Buparvaquone, Menadione, 2-acetoxy-1,4-naphthoquinone and 2-ethoxy-1,4-naphthoquinone, to HL-7702 cells were determined. The results showed that the toxicities of these naphthoquinones were characterized by a steep response pattern except for 2-hydroxy-1,4-naphthoquinone. Meanwhile, the cellular injuries were unrecoverable. Several molecular descriptors, such as the octanol-water partition coefficients (LogP), diameter (Dia) and topological index (TIndx), played an important role in the toxicity of naphthoquinones to HL-7702 cell. Our results provide a foundation for further investigation using 3D-QSAR and HQSAR to evaluate the aquatic ecological risk and the possible mechanisms of toxicity of naphthoquinones.

  10. Distribution of Chromosome Breakpoints in Human Epithelial Cells Exposed to Low- and High-LET Radiation

    NASA Technical Reports Server (NTRS)

    Hada, Megumi; Zhang, Ye; Cucinotta, Francis A.; Feiveson, Alan; Wu, Honglu

    2010-01-01

    Low-and high-LET radiations produced distinct breakpoint distributions. The difference of the breakpoint distributions between low-and high-LET only appeared in break ends involved in interchromosome exchanges. The breakpoint distributions for break ends participating in intrachromosome exchanges were similar. Gene-rich regions do not necessarily have more chromosome breaks. High-LET appeared to produce long live (data not shown) or longer live breaks that can migrate a longer distance before rejoining with other breaks. Domains occupied by different segments of the chromosomes may be responsible for the breakpoint distribution. The dose responses for interchromosomal exchanges were linear in all four exposures. However, the dose response for intrachromosomal exchanges were none linear. Increasing dose of high dose rate exposure (Fe-ions or -rays) increase the fraction of cells with intrachromosome aberrations, whereas increasing dose of low dose rate exposure (neutrons or -rays) does not affect the fraction of cells with intrachromosome aberrations.

  11. Analysis of lysosomal membrane proteins exposed to melanin in HeLa cells

    PubMed Central

    2016-01-01

    Objectives There have been developed to use targeting ability for antimicrobial, anticancerous, gene therapy and cosmetics through analysis of various membrane proteins isolated from cell organelles. Methods It was examined about the lysosomal membrane protein extracted from lysosome isolated from HeLa cell treated by 100 ppm melanin for 24 hours in order to find associated with targeting ability to melanin using by 2-dimensional electrophoresis. Results The result showed 14 up-regulated (1.5-fold) and 13 down-regulated (2.0-fold) spots in relation to melanin exposure. Conclusions It has been found that lysosomal membrane proteins are associated with melanin to decolorize and quantity through cellular activation of lysosome. PMID:27158002

  12. Proteomic studies in zebrafish liver cells exposed to the brominated flame retardants HBCD and TBBPA.

    PubMed

    Kling, Peter; Förlin, Lars

    2009-10-01

    Proteomic effect screening in zebrafish liver cells was performed to generate hypotheses regarding single and mixed exposure to the BFRs HBCD and TBBPA. Responses at sublethal exposure were analysed by two-dimensional gel electrophoresis followed by MALDI-TOF and FT-ICR protein identification. Mixing of HBCD and TBBPA at sublethal doses of individual substances seemed to increase toxicity. Proteomic analyses revealed distinct exposure-specific and overlapping responses suggesting novel mechanisms with regard to HBCD and TBBPA exposure. While distinct HBCD responses were related to decreased protein metabolism, TBBPA revealed effects related to protein folding and NADPH production. Overlapping responses suggest increased gluconeogenesis (GAPDH and aldolase) while distinct mixture effects suggest a pronounced NADPH production and changes in proteins related to cell cycle control (prohibitin and crk-like oncogene). We conclude that mixtures containing HBCD and TBBPA may result in unexpected effects highlighting proteomics as a sensitive tool for detecting and hypothesis generation of mixture effects.

  13. Persistent visceral allodynia in rats exposed to colorectal irradiation is reversed by mesenchymal stromal cell treatment.

    PubMed

    Durand, Christelle; Pezet, Sophie; Eutamène, Hélène; Demarquay, Christelle; Mathieu, Noëlle; Moussa, Lara; Daudin, Rachel; Holler, Valérie; Sabourin, Jean-Christophe; Milliat, Fabien; François, Agnès; Theodorou, Vassilia; Tamarat, Radia; Benderitter, Marc; Sémont, Alexandra

    2015-08-01

    Each year, millions of people worldwide are treated for primary or recurrent pelvic malignancies, involving radiotherapy in almost 50% of cases. Delayed development of visceral complications after radiotherapy is recognized in cancer survivors. Therapeutic doses of radiation may lead to the damage of healthy tissue around the tumor and abdominal pain. Because of the lack of experimental models, the underlying mechanisms of radiation-induced long-lasting visceral pain are still unknown. This makes managing radiation-induced pain difficult, and the therapeutic strategies proposed are mostly inefficient. The aim of our study was to develop an animal model of radiation-induced visceral hypersensitivity to (1) analyze some cellular and molecular mechanisms involved and (2) to test a therapeutic strategy using mesenchymal stromal cells (MSCs). Using a single 27-Grays colorectal irradiation in rats, we showed that such exposure induces a persistent visceral allodynia that is associated with an increased spinal sensitization (enhanced p-ERK neurons), colonic neuroplasticity (as increased density of substance P nerve fibers), and colonic mast cell hyperplasia and hypertrophy. Mast cell stabilization by ketotifen provided evidence of their functional involvement in radiation-induced allodynia. Finally, intravenous injection of 1.5 million MSCs, 4 weeks after irradiation, induced a time-dependent reversion of the visceral allodynia and a reduction of the number of anatomical interactions between mast cells and PGP9.5+ nerve fibers. Moreover, unlike ketotifen, MSC treatment has the key advantage to limit radiation-induced colonic ulceration. This work provides new insights into the potential use of MSCs as cellular therapy in the treatment of pelvic radiation disease.

  14. Disruption of cardiogenesis in human embryonic stem cells exposed to trichloroethylene.

    PubMed

    Jiang, Yan; Wang, Dan; Zhang, Guoxing; Wang, Guoqing; Tong, Jian; Chen, Tao

    2016-11-01

    Trichloroethylene (TCE) is ubiquitous in our living environment, and prenatal exposure to TCE is reported to cause congenital heart disease in humans. Although multiple studies have been performed using animal models, they have limited value in predicting effects on humans due to the unknown species-specific toxicological effects. To test whether exposure to low doses of TCE induces developmental toxicity in humans, we investigated the effect of TCE on human embryonic stem cells (hESCs) and cardiomyocytes (derived from the hESCs). In the current study, hESCs cardiac differentiation was achieved by using differentiation medium consisting of StemPro-34. We examined the effects of TCE on cell viability by cell growth assay and cardiac inhibition by analysis of spontaneously beating cluster. The expression levels of genes associated with cardiac differentiation and Ca(2+) channel pathways were measured by immunofluorescence and qPCR. The overall data indicated the following: (1) significant cardiac inhibition, which was characterized by decreased beating clusters and beating rates, following treatment with low doses of TCE; (2) significant up-regulation of the Nkx2.5/Hand1 gene in cardiac progenitors and down regulation of the Mhc-7/cTnT gene in cardiac cells; and (3) significant interference with Ca(2+) channel pathways in cardiomyocytes, which contributes to the adverse effect of TCE on cardiac differentiation during early embryo development. Our results confirmed the involvement of Ca(2+) turnover network in TCE cardiotoxicity as reported in animal models, while the inhibition effect of TCE on the transition of cardiac progenitors to cardiomyocytes is unique to hESCs, indicating a species-specific effect of TCE on heart development. This study provides new insight into TCE biology in humans, which may help explain the development of congenital heart defects after TCE exposure. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1372-1380, 2016. © 2015 Wiley

  15. Extracellular signal-regulated kinases 1 and 2 activation in endothelial cells exposed to cyclic strain

    NASA Technical Reports Server (NTRS)

    Ikeda, M.; Takei, T.; Mills, I.; Kito, H.; Sumpio, B. E.

    1999-01-01

    The aim of this study was to determine whether extracellular signal-regulated kinases 1/2 (ERK1/ERK2) are activated and might play a role in enhanced proliferation and morphological change induced by strain. Bovine aortic endothelial cells (BAEC) were subjected to an average of 6 or 10% strain at a rate of 60 cycles/min for up to 4 h. Cyclic strain caused strain- and time-dependent phosphorylation and activation of ERK1/ERK2. Peak phosphorylation and activation of ERK1/ERK2 induced by 10% strain were at 10 min. A specific ERK1/ERK2 kinase inhibitor, PD-98059, inhibited phosphorylation and activation of ERK1/ERK2 but did not inhibit the increased cell proliferation and cell alignment induced by strain. Treatment of BAEC with 2,5-di-tert-butyl-1, 4-benzohydroquinone, to deplete inositol trisphosphate-sensitive calcium storage, and gadolinium chloride, a Ca2+ channel blocker, did not inhibit the activation of ERK1/ERK2. Strain-induced ERK1/ERK2 activation was partly inhibited by the protein kinase C inhibitor calphostin C and completely inhibited by the tyrosine kinase inhibitor genistein. These data suggest that 1) ERK1/ERK2 are not critically involved in the strain-induced cell proliferation and orientation, 2) strain-dependent activation of ERK1/ERK2 is independent of intracellular and extracellular calcium mobilization, and 3) protein kinase C activation and tyrosine kinase regulate strain-induced activation of ERK1/ERK2.

  16. Differential effects of antipsychotics on the development of rat oligodendrocyte precursor cells exposed to cuprizone.

    PubMed

    Xu, Haiyun; Yang, Hong-Ju; Li, Xin-Min

    2014-03-01

    Cuprizone (CPZ) is a copper-chelating agent and has been shown to induce white matter damage in mice and rats. The compromised white matter and oligodendrocytes (OLs) respond to some antipsychotics in vivo. However, little is known about the effects of antipsychotics on cultured OLs in the presence of CPZ. The aim of this study was to examine effects of some antipsychotics on developing OLs in the presence of CPZ. Oligodendrocyte progenitor cells (OPCs) were prepared from rat embryos; OLs at different developing stages were labeled with specific antibodies; levels of CNP and MBP proteins in mature OLs were assessed by Western-blot analysis; malondialdehyde (MDA) levels and activity of catalase were evaluated as well for an assessment of oxidative stress and antioxidative status. In immunofluorescent staining, CPZ was shown to inhibit the differentiation of cultured OPCs into O4-positive cells, reduce the maturation of O4-positive cells into CNP- and MBP-positive cells, and decrease levels of CNP and MBP in mature OLs. These inhibitory effects of CPZ were ameliorated by clozapine and quetiapine (QUE), but not by haloperidol and olanzapine. Further experiments were performed to explore the mechanism of the protective effects of QUE. QUE attenuated the decreases in CNP and MBP in CPZ-treated OLs, and blocked the CPZ-induced increase in MDA and decrease in catalase activity in cultured OLs. These results are relevant to the pathophysiology and treatment of schizophrenia considering the aberrant white matter development and evidence suggesting the derangement of the oxidant and antioxidant defense system in some of the patients with schizophrenia.

  17. Genotoxic Changes to Rodent Cells Exposed in Vitro to Tungsten, Nickel, Cobalt and Iron

    DTIC Science & Technology

    2014-03-10

    available gene chips. The results obtained were compared to untreated controls and tantalum -treated cells. Tantalum has been shown to be an inert non...serum mutagenicity studies with rats implanted with depleted uranium or tantalum pellets. Mutagenesis 1998, 13, 643–648. 6. McClain, D.E.; Benson, K.A...bone and tantalum , niobium or commercially pure titanium. Biomaterials 1990, 11, 277–280. 32. Fan, J.B.; Gunderson, K.L.; Bibikova, M.; Yeakley, J.M

  18. In vivo sulfhydryl distribution in brown cells of Mercenaria mercenaria exposed to cadmium

    SciTech Connect

    Zaroogian, G.

    1995-12-31

    Brown cells are found in the red glands of Mercenaria mercenaria (Bivalvia) and have a role in detoxification. Brown cell involvement in metal detoxification is due in part to endogenous glutathione (GSH) and protein bound sulfhydryl (PBSH). During treatment of Mercenaria with 0.5 and 1.0 ppm Cd{sup 2+}, brown cells were analyzed for total sulfhydryl (TSH), PBSH, non-protein bound sulfhydryl (NPSH) and GSH after 0.25, 1, 2, 3, 6, 12 and 20 days. Trend analyses indicated that treatment with 0.5 ppm Cd{sup 2+} caused a continuous increase in PBSH/TSH, whereas NPSH/TSH did not appear to change during 20 days treatment. The GSH/NPSH ratio increased significantly (P<0.01) for 6 days, followed by a significant (P<0.01) continuous decrease to day 20. Treatment with 1.0 ppm Cd{sup 2+} caused an increase in NPSH/TSH during the first 3 days, after which the ratio remained fairly constant to day 20, whereas PBSH/TSH decreased today 2, increased to day 3 and remained unchanged to day 20. The GSH/NPSH ratio remained fairly constant for the first 12 days after which it increased significantly (P<0.01). Histopathological examination after treatment with 1.0 ppm Cd 2{sup +} indicated darkening of the lysosomes during the first 2 days, followed by extensive brown cell sloughing into the tubule lumen and the abundance of small lysosomes at day 3. Sloughing and small lysosome formation continued to a lesser extent to day 20 when granulocyte infiltration and necrosis of the intertubular connective tissue occurred. The data indicate that GSH is more resistant to fluctuations than PBSH which suggests a more rapid synthesis or turnover rate for GSH. The ratio of GSH to PBSH has potential for a biomarker of cadmium exposure and health of Mercenaria.

  19. Changes in protein expression of U937 and Jurkat cells exposed to nanosecond pulsed electric fields

    NASA Astrophysics Data System (ADS)

    Moen, Erick K.; Roth, Caleb C.; Cerna, Caesar; Estalck, Larry; Wilmink, Gerald; Ibey, Bennett L.

    2013-02-01

    Application of nanosecond pulsed electric fields (nsPEF) to various biological cell lines has been to shown to cause many diverse effects, including poration of the plasma membrane, depolarization of the mitochondrial membrane, blebbing, apoptosis, and intracellular calcium bursts. The underlying mechanism(s) responsible for these diverse responses are poorly understood. Of specific interest in this paper are the long-term effects of nsPEF on cellular processes, including the regulation of genes and production of proteins. Previous studies have reported transient activation of select signaling pathways involving mitogen-activated protein kinases (MAPKs), protein phosphorylation and downstream gene expression following nsPEF application. We hypothesize that nsPEF represents a unique stimulus that could be used to externally modulate cellular processes. To validate our hypothesis, we performed a series of cuvette-based exposures at 10 and 600ns pulse widths using a custom Blumlien line pulser system. We measured acute changes in the plasma membrane structure using flow cytometry by tracking phosphatidylserine externalization via FITC-Annexin V labeling and poration via propidium iodide uptake. We then compared these results to viability of the cells at 24 hours post exposure using MTT assay and changes in the MAPK family of proteins at 8 hours post-exposure using Luminex assay. By comparing exposures at 10 and 600ns duration, we found that most MAPK family-protein expression increased in Jurkat and U937 cell lines following exposure and compared well with drops in viability and changes in plasma membrane asymmetry. What proved interesting is that some MAPK family proteins (e.g. p53, STAT1), were expressed in one cell line, but not the other. This difference may point to an underlying mechanism for observed difference in cellular sensitivity to nsPEFinduced stresses.

  20. Extracellular signal-regulated kinases 1 and 2 activation in endothelial cells exposed to cyclic strain

    NASA Technical Reports Server (NTRS)

    Ikeda, M.; Takei, T.; Mills, I.; Kito, H.; Sumpio, B. E.

    1999-01-01

    The aim of this study was to determine whether extracellular signal-regulated kinases 1/2 (ERK1/ERK2) are activated and might play a role in enhanced proliferation and morphological change induced by strain. Bovine aortic endothelial cells (BAEC) were subjected to an average of 6 or 10% strain at a rate of 60 cycles/min for up to 4 h. Cyclic strain caused strain- and time-dependent phosphorylation and activation of ERK1/ERK2. Peak phosphorylation and activation of ERK1/ERK2 induced by 10% strain were at 10 min. A specific ERK1/ERK2 kinase inhibitor, PD-98059, inhibited phosphorylation and activation of ERK1/ERK2 but did not inhibit the increased cell proliferation and cell alignment induced by strain. Treatment of BAEC with 2,5-di-tert-butyl-1, 4-benzohydroquinone, to deplete inositol trisphosphate-sensitive calcium storage, and gadolinium chloride, a Ca2+ channel blocker, did not inhibit the activation of ERK1/ERK2. Strain-induced ERK1/ERK2 activation was partly inhibited by the protein kinase C inhibitor calphostin C and completely inhibited by the tyrosine kinase inhibitor genistein. These data suggest that 1) ERK1/ERK2 are not critically involved in the strain-induced cell proliferation and orientation, 2) strain-dependent activation of ERK1/ERK2 is independent of intracellular and extracellular calcium mobilization, and 3) protein kinase C activation and tyrosine kinase regulate strain-induced activation of ERK1/ERK2.

  1. Proteomic analysis of MCF-7 breast cancer cell line exposed to leptin.

    PubMed

    Valle, A; Sastre-Serra, J; Pol, C; Miró, A M; Oliver, J; Roca, P

    2011-01-01

    Obesity is a well-known factor risk for breast cancer in postmenopausal women. Circulating leptin levels are increased in obese and it has been suggested to play an important role in mammary tumor formation and progression. To contribute to the understanding of the molecular mechanisms underlying leptin action in breast cancer, our aim was to identify proteins regulated by leptin in MCF-7 human breast cancer cells. We used two-dimensional gel electrophoresis (2-DE) and matrix assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS) to identify proteins affected by leptin. Thirty proteins were found differentially expressed in MCF-7 cells after 48 h leptin exposure. Proteins regulated by leptin included proteins previously implicated in breast cancer such as catechol-o-methyltransferase, cathepsin D, hsp27, serine/threonine-protein phosphatase and regulatory proteins of the Ras signaling pathway. Proteins involved in other cellular functions such as stress response, cytosqueleton remodeling and proteins belonging to ubiquitin-proteasome system, were also identified. Furthermore, leptin-treated cells showed a substantial uptake of the serum carrier proteins albumin and alpha-2-HS-glycoprotein. This screening reveals that leptin influences the levels of key proteins involved in breast cancer which opens new avenues for the study of the molecular mechanisms linking obesity to breast cancer.

  2. DNA damage, photorepair, and survival in fish and human cells exposed to UV radiation

    SciTech Connect

    Ahmed, F.E.; Setlow, R.B.; Grist, E.; Setlow, N. )

    1993-01-01

    The effect of various wavelengths of UVB radiation on the induction of cyclobutane pyrimidine dimers in fish cells and human fibroblasts and the repair of these lesions were studied using an UV-endonuclease to measure dimers (endonuclease sensitive sites) by sedimentation of radioactive DNA, by gel electrophoresis of unlabeled DNA, and by cell survival. The data show that fish cells have an efficient photoreactivation system at wavelength > 304 nm that reverses cytoxicity and dimer formation after exposure to filtered sunlamp irradiation of a shorter wavelength ([lambda] > 290 nm). Shorter wavelengths in UVB (>304 nm) are more effective in photoreversal than longer ones (>320 nm). As a consequence, 50-85% of dimers induced by these wavelengths in fish are photoreactivated while they are being formed. A major cytotoxicological lesion is the cyclobutane pyrimidine dimers. Cultured human fibroblasts do not possess such a repair system. These results indicate that sunlamp irradiation has wavelengths that both damage and repair DNA. 37 refs., 5 figs., 1 tab.

  3. Ultrastructural study of mitochondrial damage in CHO cells exposed to hyperthermia.

    PubMed

    Cole, A; Armour, E P

    1988-09-01

    A unique direct-view stereo electron microscope technique was used to visualize the structure and three-dimensional distributions of mitochondria in CHO cells in situ following hyperthermic treatments. Aberrations induced by various heating regimens were recorded. The protocol included a trypsin digestion that may have enhanced the expression of the initial heat damage. The developed damage was observed as increasing levels of mitochondrial distortion, swelling, and dissociation. Minimal damage was induced at 42 degrees C for exposures of up to 4 h, while significant damage was induced at 43 degrees C for exposures of more than 30 min and at 45 degrees C for exposures of more than 10 min. For moderate exposures, a partial recovery of mitochondrial integrity was observed when the heat treatment was followed by incubation at 37 degrees C for 24 h. Mitochondrial damage was related to the heat dose in that increasing treatment temperature resulted in greater damage, but when compared to cell survival the damage did not parallel cell killing under all time-temperature conditions.

  4. Cytotoxicity and induction of protective mechanisms in HepG2 cells exposed to cadmium.

    PubMed

    Urani, C; Melchioretto, P; Canevali, C; Crosta, G F

    2005-10-01

    Cadmium is a widespread industrial pollutant. The primary route of exposure occurs via contaminated drinking water or food supplies, and tobacco. Its chronic introduction and ingestion lead to bio-magnification in target organs, as the liver. The aim of this paper is to determine Cd cytotoxic concentrations in the human hepatoma cell line HepG2. Further aims are the study of the activation and involvement of protection mechanisms against Cd hepatotoxicity. Cd was accumulated within the cells, as measured by ICP-AES. Metallothioneins (MT-1 and -2), a family of metal-binding proteins, were induced in a dose-dependent way after treatment with concentrations below the IC(50) value (mean value 22 microM). The over-expression of MT by Zn pre-treatment was able to defend against Cd cytotoxicity. Heat shock protein 70 kDa (hsp70) was induced at high non-cytotoxic concentrations (5, 10 microM) probably as a consequence of proteotoxicity, but its over-expression by a sub-lethal heat shock was not able to protect the cells from Cd cytotoxic concentrations (20, 50, 100 microM).

  5. Cord blood dendritic cell subsets in African newborns exposed to Plasmodium falciparum in utero.

    PubMed

    Breitling, Lutz P; Fendel, Rolf; Mordmueller, Benjamin; Adegnika, Ayola A; Kremsner, Peter G; Luty, Adrian J F

    2006-10-01

    Placent