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Maier A, Bailey T, Hinrichs A, Lerchl S, Newman RT, Fournier C, Vandevoorde C. Experimental Setups for In Vitro Studies on Radon Exposure in Mammalian Cells-A Critical Overview. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2023; 20:ijerph20095670. [PMID: 37174189 PMCID: PMC10178159 DOI: 10.3390/ijerph20095670] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Revised: 04/20/2023] [Accepted: 04/24/2023] [Indexed: 05/15/2023]
Abstract
Naturally occurring radon and its short lived progeny are the second leading cause of lung cancer after smoking, and the main risk factor for non-smokers. The radon progeny, mainly Polonium-218 (218Po) and Polonium-214 (214Po), are responsible for the highest dose deposition in the bronchial epithelium via alpha-decay. These alpha-particles release a large amount of energy over a short penetration range, which results in severe and complex DNA damage. In order to unravel the underlying biological mechanisms which are triggered by this complex DNA damage and eventually give rise to carcinogenesis, in vitro radiobiology experiments on mammalian cells have been performed using radon exposure setups, or radon analogues, which mimic alpha-particle exposure. This review provides an overview of the different experimental setups, which have been developed and used over the past decades for in vitro radon experiments. In order to guarantee reliable results, the design and dosimetry of these setups require careful consideration, which will be emphasized in this work. Results of these in vitro experiments, particularly on bronchial epithelial cells, can provide valuable information on biomarkers, which can assist to identify exposures, as well as to study the effects of localized high dose depositions and the heterogeneous dose distribution of radon.
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Affiliation(s)
- Andreas Maier
- Biophysics Department, GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt, Germany
| | - Tarryn Bailey
- Department of Physics, Stellenbosch University, Stellenbosch, Cape Town 7600, South Africa
- Radiation Biophysics Division, Separated Sector Cyclotron Laboratory, NRF-iThemba LABS, Cape Town 7129, South Africa
| | - Annika Hinrichs
- Biophysics Department, GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt, Germany
- Physics Department, Goethe University Frankfurt am Main, 60438 Frankfurt am Main, Germany
| | - Sylvie Lerchl
- Biophysics Department, GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt, Germany
| | - Richard T Newman
- Department of Physics, Stellenbosch University, Stellenbosch, Cape Town 7600, South Africa
| | - Claudia Fournier
- Biophysics Department, GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt, Germany
| | - Charlot Vandevoorde
- Biophysics Department, GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt, Germany
- Radiation Biophysics Division, Separated Sector Cyclotron Laboratory, NRF-iThemba LABS, Cape Town 7129, South Africa
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Moreira HM, Guerra Liberal FD, McMahon SJ, Prise KM. Characterization of a custom-made 241Am alpha-source for radiobiological studies. Appl Radiat Isot 2021; 177:109931. [PMID: 34488046 DOI: 10.1016/j.apradiso.2021.109931] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Revised: 08/15/2021] [Accepted: 08/29/2021] [Indexed: 01/04/2023]
Abstract
A compact in-house alpha particle source has been developed and fully characterized. The irradiation source is a large area, 25 cm2, 5.4 MeV average energy 241Am source, above which a Mylar dish containing a monolayer of target cells can be placed at defined positions. The source uniformity, flux, particle energy and dose rate were determined experimentally. The dose rate to the nucleus at the closest position was 1.57 Gy/min. Furthermore, a 3D printed collimator was tested and found to improve the uniformity of the energy spectra of particles reaching the target. For validation, prostate PC-3 cells were irradiated in our experimental setup with absorbed doses up to 2 Gy and for reference compared with cells irradiated with conventional X-rays with doses up to 8 Gy. The Relative Biological Effectiveness for alpha particles at 10% survival was 3.66± 0.40 agreeing with previously published data. Data presented here show the feasibility of utilising a low-cost alpha-irradiation source for accurate in vitro assays to better understand the radiobiological effects of high LET alpha particles.
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Affiliation(s)
- Hugo Mr Moreira
- The Patrick G Johnston Centre for Cancer Research, Queen's University of Belfast, 97 Lisburn Road, Belfast, BT9 7AE, United Kingdom
| | - Francisco Dc Guerra Liberal
- The Patrick G Johnston Centre for Cancer Research, Queen's University of Belfast, 97 Lisburn Road, Belfast, BT9 7AE, United Kingdom.
| | - Stephen J McMahon
- The Patrick G Johnston Centre for Cancer Research, Queen's University of Belfast, 97 Lisburn Road, Belfast, BT9 7AE, United Kingdom
| | - Kevin M Prise
- The Patrick G Johnston Centre for Cancer Research, Queen's University of Belfast, 97 Lisburn Road, Belfast, BT9 7AE, United Kingdom
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Maier A, Wiedemann J, Adrian JA, Dornhecker M, Zipf A, Kraft-Weyrather W, Kraft G, Richter S, Teuscher N, Fournier C. α-Irradiation setup for primary human cell cultures. Int J Radiat Biol 2019; 96:206-213. [PMID: 31682776 DOI: 10.1080/09553002.2020.1683641] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Purpose: We present an α-irradiation setup for the irradiation of primary human cell cultures under controlled conditions using 241Am α-particles.Materials and Methods: To irradiate samples with α-particles in a valid manner, a reliable dosimetry is a great challenge because of the short α-range and the complex energy spectrum. Therefore, the distance between α-source and sample must be minimal. In the present setup, this is achieved by cells growing on a 2 μm thick biaxially-oriented polyethylene terephthalate (boPET) foil which is only 2.7 mm apart from the source. A precise and reproducible exposure time is realized through a mechanical shutter. The fluence, energy spectra and the corresponding linear energy transfer are determined by the source geometry and the material traversed. They were measured and calculated, yielding a dose rate of 8.2 ± 2.4 Gy/min. To improve cell growth on boPET foils, they were treated with air plasma. This treatment increased the polarity and thus the ability of cells attaching to the surface of the foil. Several tests including cell growth, staining for a marker of DNA double-strand breaks and a colony-forming assay were performed and confirm our dosimetry.Conclusion: With our setup, it is possible to irradiate cell cultures under defined conditions with α-particles. The plasma-treated foil is suitable for primary human cell cultures as shown in cell experiments, confirming also the expected number of particle traversals.
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Affiliation(s)
- Andreas Maier
- GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany
| | - Julia Wiedemann
- GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany
| | - Julia Anna Adrian
- GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany.,Physics Department, Technical University, Darmstadt, Germany
| | - Maximilian Dornhecker
- GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany.,Biophysics Department, Goethe University, Frankfurt, Germany
| | - Andreas Zipf
- GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany.,Physics Department, Technical University, Darmstadt, Germany
| | | | - Gerhard Kraft
- GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany
| | - Sandra Richter
- Fraunhofer-Institut für Mikrostruktur von Werkstoffen und Systemen IMWS, Halle, Germany
| | - Nico Teuscher
- Fraunhofer-Institut für Mikrostruktur von Werkstoffen und Systemen IMWS, Halle, Germany
| | - Claudia Fournier
- GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany
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Sihver L, Ni J, Sun L, Kong D, Ren Y, Gu S. Voxel model of individual cells and its implementation in microdosimetric calculations using GEANT4. RADIATION AND ENVIRONMENTAL BIOPHYSICS 2014; 53:571-579. [PMID: 24878548 DOI: 10.1007/s00411-014-0549-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2013] [Accepted: 05/11/2014] [Indexed: 06/03/2023]
Abstract
Accurate dosimetric calculations at cellular and sub-cellular levels are crucial to obtain an increased understanding of the interactions of ionizing radiation with a cell and its nucleus and cytoplasm. Ion microbeams provide a superior opportunity to irradiate small biological samples, e.g., DNA, cells, and to compare their response to computer simulations. However, the phantoms used to simulate small biological samples at cellular levels are often simplified as simple volumes filled with water. As a first step to improve the situation in comparing measurements of cell response to ionizing radiation with model calculations, a realistic voxel model of a KB cell was constructed and used together with an already constructed geometry and tracking 4 (GEANT4) model of the horizontal microbeam line of the Centre d'Etudes Nucléaires de Bordeaux-Gradignan (CENBG) 3.5 MV Van de Graaf accelerator at the CENBG, France. The microbeam model was then implemented into GEANT4 for simulations of the average number of particles hitting an irradiated cell when a specified number of particles are produced in the beam line. The result shows that when irradiating the developed voxel model of a KB cell with 200 α particles, with a nominal energy of 3 MeV in the beam line and 2.34 MeV at the cell entrance, 100 particles hit the cell on average. The mean specific energy is 0.209 ± 0.019 Gy in the nucleus and 0.044 ± 0.001 Gy in the cytoplasm. These results are in agreement with previously published data, which indicates that this model could act as a reference model for dosimetric calculations of radiobiological experiments, and that the proposed method could be applied to build a cell model database.
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Affiliation(s)
- Lembit Sihver
- School of Radiation Medicine and Protection, Medical College of Soochow University, Suzhou, Jiangsu, China
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Chauhan V, Howland M, Wilkins R. Identification of gene-based responses in human blood cells exposed to alpha particle radiation. BMC Med Genomics 2014; 7:43. [PMID: 25017500 PMCID: PMC4128605 DOI: 10.1186/1755-8794-7-43] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2014] [Accepted: 07/07/2014] [Indexed: 12/20/2022] Open
Abstract
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.
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Affiliation(s)
- Vinita Chauhan
- Consumer and Clinical Radiation Protection Bureau, Healthy Environment and Consumer Safety Branch, Health Canada, 775 Brookfield Road, PL 6303B, Ottawa, ON K1A 1C1, Canada.
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6
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Chauhan V, Howland M. Gene expression responses in human lung fibroblasts exposed to alpha particle radiation. Toxicol In Vitro 2014; 28:1222-9. [PMID: 24945610 DOI: 10.1016/j.tiv.2014.06.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2013] [Revised: 04/14/2014] [Accepted: 06/03/2014] [Indexed: 11/24/2022]
Abstract
This study examined alpha (α-) particle radiation effects on global changes in gene expression for the purposes of identifying potential signaling pathways that may be involved in Radon ((222)Rn) gas exposure and lung carcinogenesis. Human lung fibroblast cells were exposed to α-particle radiation at a dose range of 0-1.5Gy. Twenty-four hours post-exposure, transcript modulations were monitored using microarray technology. A total of 208 genes were shown to be dose-responsive (FDR adjusted p<0.05, Fold change>|2|) of which 32% were upregulated and 68% downregulated. Fourteen of the high expressing genes (>|4| fold) were further validated using alternate technology and among these genes, GDF15 and FGF2 were assessed at the protein level. GDF15, a known marker of lung injury, had expression levels 3-fold higher in exposed cell culture media, 24h post-irradiation as detected by ELISA. Further, pathway analysis of the dose-responsive transcripts showed them to be involved in biological processes related to cell cycle control/mitosis, chromosome instability and cell differentiation. This panel of genes with particular focus on GDF15 may merit further analysis to determine their specific role in mechanisms leading to α-particle induced lung carcinogenesis.
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Affiliation(s)
- Vinita Chauhan
- Consumer and Clinical Radiation Protection Bureau, Healthy Environment and Consumer Safety Branch, Health Canada, Ottawa, Ontario K1A 0K9, Canada.
| | - Matthew Howland
- Consumer and Clinical Radiation Protection Bureau, Healthy Environment and Consumer Safety Branch, Health Canada, Ottawa, Ontario K1A 0K9, Canada
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Jeynes JCG, Merchant MJ, Barazzuol L, Barry M, Guest D, Palitsin VV, Grime GW, Tullis IDC, Barber PR, Vojnovic B, Kirkby KJ. "Broadbeam" irradiation of mammalian cells using a vertical microbeam facility. RADIATION AND ENVIRONMENTAL BIOPHYSICS 2013; 52:513-21. [PMID: 23963461 DOI: 10.1007/s00411-013-0487-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2012] [Accepted: 08/08/2013] [Indexed: 06/02/2023]
Abstract
A "broadbeam" facility is demonstrated for the vertical microbeam at Surrey's Ion Beam Centre, validating the new technique used by Barazzuol et al. (Radiat Res 177:651-662, 2012). Here, droplets with a diameter of about 4 mm of 15,000 mammalian cells in suspension were pipetted onto defined locations on a 42-mm-diameter cell dish with each droplet individually irradiated in "broadbeam" mode with 2 MeV protons and 4 MeV alpha particles and assayed for clonogenicity. This method enables multiple experimental data points to be rapidly collected from the same cell dish. Initially, the Surrey vertical beamline was designed for the targeted irradiation of single cells with single counted ions. Here, the benefits of both targeted single-cell and broadbeam irradiations being available at the same facility are discussed: in particular, high-throughput cell irradiation experiments can be conducted on the same system as time-intensive focused-beam experiments with the added benefits of fluorescent microscopy, cell recognition and time-lapse capabilities. The limitations of the system based on a 2 MV tandem accelerator are also discussed, including the uncertainties associated with particle Poisson counting statistics, spread of linear energy transfer in the nucleus and a timed dose delivery. These uncertainties are calculated with Monte Carlo methods. An analysis of how this uncertainty affects relative biological effect measurements is made and discussed.
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Affiliation(s)
- J C G Jeynes
- Ion Beam Centre, University of Surrey, Guildford, GU2 7XH, UK,
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8
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Riquier H, Wera AC, Heuskin AC, Feron O, Lucas S, Michiels C. Comparison of X-ray and alpha particle effects on a human cancer and endothelial cells: Survival curves and gene expression profiles. Radiother Oncol 2013; 106:397-403. [DOI: 10.1016/j.radonc.2013.02.017] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2011] [Revised: 11/22/2012] [Accepted: 02/15/2013] [Indexed: 01/15/2023]
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Chauhan V, Howland M. Genomic profiling of a human leukemic monocytic cell-line (THP-1) exposed to alpha particle radiation. ScientificWorldJournal 2012; 2012:205038. [PMID: 23097634 PMCID: PMC3477555 DOI: 10.1100/2012/205038] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2012] [Accepted: 09/02/2012] [Indexed: 11/26/2022] Open
Abstract
This study examined alpha (α-) particle radiation effects on global changes in gene expression in human leukemic monocytic cells (THP-1) for the purposes of mining for candidate biomarkers that could be used for the development of a biological assessment tool. THP-1 cells were exposed to α-particle radiation at a dose range of 0 to 1.5 Gy. Twenty-four hours and three days after exposure gene expression was monitored using microarray technology. A total of 16 genes were dose responsive and classified as early onset due to their expression 24 h after exposure. Forty-eight transcripts were dose responsive and classified as late-onset as they were expressed 72 h after exposure. Among these genes, 6 genes were time and dose responsive and validated further using alternate technology. These transcripts were upregulated and associated with biological processes related to immune function, organelle stability and cell signalling/communication. This panel of genes merits further validation to determine if they are strong candidate biomarkers indicative of α-particle exposure.
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Affiliation(s)
- Vinita Chauhan
- Consumer and Clinical Radiation Protection Bureau, Health Canada, Healthy Environment and Consumer Safety Branch, Ottawa, ON, Canada K1A 0K9. vinita
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Chauhan V, Howland M, Mendenhall A, O'Hara S, Stocki TJ, McNamee JP, Wilkins RC. Effects of alpha particle radiation on gene expression in human pulmonary epithelial cells. Int J Hyg Environ Health 2012; 215:522-35. [PMID: 22608759 DOI: 10.1016/j.ijheh.2012.04.004] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2011] [Revised: 03/27/2012] [Accepted: 04/15/2012] [Indexed: 01/11/2023]
Abstract
The general public receives approximately half of its exposure to natural radiation through alpha (α)-particles from radon ((222)Rn) gas and its decay progeny. Epidemiological studies have found a positive correlation between exposure to (222)Rn and lung carcinogenesis. An understanding of the transcriptional responses involved in these effects remains limited. In this study, genomic technology was employed to mine for subtle changes in gene expression that may be representative of an altered physiological state. Human lung epithelial cells were exposed to 0, 0.03, 0.3 and 0.9Gy of α-particle radiation. Microarray analysis was employed to determine transcript expression levels 4h and 24h after exposure. A total of 590 genes were shown to be differentially expressed in the α-particle radiated samples (false discovery rate (FDR)≤0.05). Sub-set of these transcripts were time-responsive, dose-responsive and both time- and dose-responsive. Pathway analysis showed functions related to cell cycle arrest, and DNA replication, recombination and repair (FDR≤0.05). The canonical pathways associated with these genes were in relation to pyrimidine metabolism, G2/M damage checkpoint regulation and p53 signaling (FDR≤0.05). Overall, this gene expression profile suggests that α-particle radiation inhibits DNA synthesis and subsequent mitosis, and causes cell cycle arrest.
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Affiliation(s)
- Vinita Chauhan
- Environmental and Radiation Health Sciences Directorate, Health Canada, Ottawa, Ontario, Canada K1A 0K9. Vinita
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Chauhan V, Howland M, Wilkins R. A comparitive assessement of cytokine expression in human-derived cell lines exposed to alpha particles and X-rays. ScientificWorldJournal 2012; 2012:609295. [PMID: 22619631 PMCID: PMC3347887 DOI: 10.1100/2012/609295] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2011] [Accepted: 12/05/2011] [Indexed: 12/25/2022] Open
Abstract
Alpha- (α-) particle radiation exposure has been linked to the development of lung cancer and has been identified as a radiation type likely to be employed in radiological dispersal devices. Currently, there exists a knowledge gap concerning cytokine modulations associated with exposure to α-particles. Bio-plex technology was employed to investigate changes in proinflammatory cytokines in two human-derived cell lines. Cells were irradiated at a dose of 1.5 Gy to either α-particles or X-rays at equivalent dose rates. The two cell lines exhibited a unique pattern of cytokine expression and the response varied with radiation type. Of the 27 cytokines assessed, only vascular endothelin growth factor (VEGF) was observed to be modulated in both cell lines solely after α-particle exposure, and the expression of VEGF was shown to be dose responsive. These results suggest that certain proinflammatory cytokines may be involved in the biological effects related to α- particle exposure and the responses are cell type and radiation type specific.
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Affiliation(s)
- Vinita Chauhan
- Consumer and Clinical Radiation Protection Bureau, Health Canada, Ottawa, ON, Canada.
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Barberet P, Vianna F, Karamitros M, Brun T, Gordillo N, Moretto P, Incerti S, Seznec H. Monte-Carlo dosimetry on a realistic cell monolayer geometry exposed to alpha particles. Phys Med Biol 2012; 57:2189-207. [DOI: 10.1088/0031-9155/57/8/2189] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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Chauhan V, Howland M, Wilkins R. Effects of α-Particle Radiation on MicroRNA Responses in Human Cell-Lines. Open Biochem J 2012; 6:16-22. [PMID: 22481983 PMCID: PMC3314867 DOI: 10.2174/1874091x01206010016] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2011] [Revised: 01/21/2012] [Accepted: 02/14/2012] [Indexed: 11/22/2022] Open
Abstract
A variety of alpha (α)-particle emitters are found ubiquitously in the environment, in commercial/therapeutic prod-ucts and are a potential threat in the form of a radiological dispersal device. Our understanding of the biological mechanisms and long-term health effects resulting from α-particle exposure is limited. Exposure to radiation induces modulations of gene networks, possibly through microRNAs (miRNAs), which could be targets for studying biological effects. In this study, changes in miRNA expression patterns after 0.5 Gy, 1.0 Gy and 1.5 Gy of α-particle radiation at a low dose-rate of exposure in three human cell-lines (A549, THP-1 and HFL) were investigated. The screening of 1,145 miRNAs across three human cell-lines resulted in unique, cell-specific responses with no overlap in miRNA expression observed in the three cell-lines. Prediction analysis suggests these α-particle induced miRNA mapped to target genes related to ribosomal assembly, lung carcinoma development, cell communication and keratin sulfate biosynthesis. Taken together, these results suggest that exposure to α-particle radiation results in cell-type specific responses in gene network regulatory processes.
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Affiliation(s)
- Vinita Chauhan
- Consumer and Clinical Radiation Protection Bureau, Health Canada, Ottawa, Ontario, K1A 0K9 Canada
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14
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Chauhan V, Howland M, Kutzner B, McNamee JP, Bellier PV, Wilkins RC. Biological effects of alpha particle radiation exposure on human monocytic cells. Int J Hyg Environ Health 2011; 215:339-44. [PMID: 22153871 DOI: 10.1016/j.ijheh.2011.11.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2011] [Revised: 10/06/2011] [Accepted: 11/08/2011] [Indexed: 01/18/2023]
Abstract
Radon ((222)Rn) gas produces decay progeny that emits high energy alpha (α)-particles. Epidemiological studies have shown that exposure to (222)Rn is linked with elevated risk of developing lung cancer, however clear mechanisms leading to such effects have not been delineated. Cytokines play a critical role in inflammation and their dysregulated production often contributes to disease pathogenesis. In this study, Bio-plex multiplex technology was employed to investigate modulations of 27 pro-inflammatory cytokines following exposure of human monocytic cells to 1.5 Gy of α-particle radiation. Concurrently, DNA damage was assessed by examining the formation of phosphorylated H2A histone family X (γ-H2AX) sites. Of the 27 cytokines assessed, 4 cytokines were shown to be statistically downregulated by ∼2 fold relative to the untreated controls and included the interleukin (IL) family of proteins (IL-2, IL-15 and IL-17) and macrophage inflammatory protein 1 beta (MIP-1b). Interferon-inducible protein-12 (IP-12), vascular endothelial growth factor and regulated on activation normal T cell expressed and secreted (RANTES) were shown to be high expressors and upregulated. Cells irradiated with α-particles ranging from 0.27 to 2.14 Gy showed statistically significant, dose-dependant increases in γ-H2AX formation. These data suggest that α-particle radiation causes dysregulation in the production of a number of pro-inflammatory cytokines and results in significant DNA damage.
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Affiliation(s)
- Vinita Chauhan
- Consumer and Clinical Radiation Protection Bureau, Health Canada, ON, Canada K1A 0K9. Vinita
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15
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Chauhan V, Howland M, Chen J, Kutzner B, Wilkins RC. Differential effects of alpha-particle radiation and x-irradiation on genes associated with apoptosis. Radiol Res Pract 2011; 2011:679806. [PMID: 22091383 PMCID: PMC3199915 DOI: 10.1155/2011/679806] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2011] [Accepted: 04/05/2011] [Indexed: 01/13/2023] Open
Abstract
This study examined differential effects of alpha-(α-) particle radiation and X-rays on apoptosis and associated changes in gene expression. Human monocytic cells were exposed to α-particle radiation and X-rays from 0 to 1.5 Gy. Four days postexposure, cell death was measured by flow cytometry and 84 genes related to apoptosis were analyzed using real-time PCR. On average, 33% of the cells were apoptotic at 1.5 Gy of α-particle radiation. Transcript profiling showed statistical expression of 15 genes at all three doses tested. Cells exposed to X-rays were <5% apoptotic at ~1.5 Gy and induced less than a 2-fold expression in 6 apoptotic genes at the higher doses of radiation. Among these 6 genes, Fas and TNF-α were common to the α-irradiated cells. This data suggests that α-particle radiation initiates cell death by TNF-α and Fas activation and through intermediate signalling mediators that are distinct from X-irradiated cells.
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Affiliation(s)
- Vinita Chauhan
- Consumer and Clinical Radiation Protection Bureau, Healthy Environments and Consumer Safety Branch, Health Canada, 775 Brookfield Road, PL 6303B, Ottawa, ON, Canada K1A 0K9
| | - Matthew Howland
- Consumer and Clinical Radiation Protection Bureau, Healthy Environments and Consumer Safety Branch, Health Canada, 775 Brookfield Road, PL 6303B, Ottawa, ON, Canada K1A 0K9
| | - Jeremy Chen
- Consumer and Clinical Radiation Protection Bureau, Healthy Environments and Consumer Safety Branch, Health Canada, 775 Brookfield Road, PL 6303B, Ottawa, ON, Canada K1A 0K9
| | - Barbara Kutzner
- Consumer and Clinical Radiation Protection Bureau, Healthy Environments and Consumer Safety Branch, Health Canada, 775 Brookfield Road, PL 6303B, Ottawa, ON, Canada K1A 0K9
| | - Ruth C. Wilkins
- Consumer and Clinical Radiation Protection Bureau, Healthy Environments and Consumer Safety Branch, Health Canada, 775 Brookfield Road, PL 6303B, Ottawa, ON, Canada K1A 0K9
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