Induction of thioredoxin in human lymphocytes with low-dose ionizing radiation

Purpose: Ionizing radiation induced foci (IRIF) known also as DNA repair foci represent most sensitive endpoint for assessing DNA double strand breaks (DSB). IRIF are usually visualized and enumerated with the aid of fluorescence microscopy using antibodies to γH2AX and 53BP1. This study analyzed effect of low dose ionizing radiation on residual IRIF in human lymphocytes to the aim of potential biodosimetry and possible extrapolation of high-dose γH2AX/53BP1 effects to low doses and compared kinetics of DSB and IRIF. We also analyzed whether DNaseI, which is used for reducing of clumps, affects the IRIF level. Materials and Methods: The cryopreserved human lymphocytes from umbilical cord blood (UCB) were thawed with/without DNaseI, γ-irradiated at doses of 0, 5, 10, and 50 cGy and γH2AX/53BP1 foci were analyzed 30 min, 2 h, and 22 h post-irradiation using appropriate antibodies. We also analyzed kinetics of DSB using PFGE. Results: No significant difference was observed between data obtained by γH2AX foci evaluation in cells that were irradiated by low doses and data obtained by extrapolation from higher doses. Residual 53BP1 foci induced by low doses significantly outreached the data extrapolated from irradiation by higher doses. 53BP1 foci induced by low dose-radiation remain longer at DSB loci than foci induced by higher doses. There was no significant effect of DNaseI on DNA repair foci. Conclusions: Primary γH2AX, 53BP1 foci and their co-localization represent valuable markers for biodosimetry of low doses, but their usefulness is limited by short time window. Residual γH2AX and 53BP1 foci are more useful markers for biodosimetry in vitro. Effects of low doses can be extrapolated from high dose using γH2AX residual foci while γH2AX/53BP1 foci are valuable markers for evaluation of initial DSB induced by ionizing radiation. Residual IRIF induced by low doses persist longer time than those induced by higher doses.

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Analysis of chromosome loss and chromosome segregation in cytokinesis-blocked human lymphocytes: non-disjunction is the prevalent mistake in chromosome segregation produced by low dose exposure to ionizing radiation

Mutagenesis ◽

10.1093/mutage/15.1.1 ◽

2000 ◽

Vol 15 (1) ◽

pp. 1-7 ◽

Cited By ~ 22

Author(s):

N. Touil

Keyword(s):

Ionizing Radiation ◽

Chromosome Segregation ◽

Low Dose ◽

Human Lymphocytes ◽

Chromosome Loss

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Radioprotective effect of pioglitazone against genotoxicity induced by ionizing radiation in human healthy lymphocytes

Cardiovascular & Hematological Agents in Medicinal Chemistry ◽

10.2174/1871525718666200525005231 ◽

2020 ◽

Vol 18 ◽

Author(s):

Roya Kazemi ◽

Seyed Jalal Hosseinimehr

Keyword(s):

Ionizing Radiation ◽

Human Lymphocytes ◽

Peroxisome Proliferator ◽

Peroxisome Proliferator Activated Receptor ◽

The Mean ◽

Anti Inflammatory ◽

Sensitizing Effect ◽

Binucleated Lymphocytes ◽

Inflammatory Effect

Objective: Pioglitazone (PG) is used to control high blood sugar in patients with type 2 diabetes mellitus. PG acts as a peroxisome proliferator-activated receptor γ agonist. In addition to the insulin-sensitizing effect, PG possesses anti-inflammatory effect. In this study, the protective effect of PG was evaluated against DNA damage induced by ionizing radiation in human healthy lymphocytes. Methods: The microtubes containing human whole blood were treated with PG at various concentrations (1-50 μM) for three hours. Then, the blood samples were irradiated with X-ray. Lymphocytes were cultured for determining the frequency of micronuclei as a genotoxicity biomarker in binucleated lymphocytes. Results: The mean percentage of micronuclei was significantly increased in human lymphocytes when were exposed to IR, while it was decreased in lymphocytes pre-treated with PG. The maximum reduction in the frequency of micronuclei in irradiated lymphocytes was observed at 5 μM of PG treatment (48% decrease). Conclusion: The anti-inflammatory property is suggested the mechanism action of PG for protection human lymphocytes against genotoxicity induced by ionizing radiation.

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A systematic review on the effect of low-dose radiation on hearing

Radiation and Environmental Biophysics ◽

10.1007/s00411-021-00926-6 ◽

2021 ◽

Author(s):

Srikanth Nayak ◽

Arivudai Nambi ◽

Sathish Kumar ◽

P Hariprakash ◽

Pradeep Yuvaraj ◽

...

Keyword(s):

Systematic Review ◽

Ionizing Radiation ◽

Radiation Exposure ◽

Low Dose ◽

Behavioral Symptoms ◽

National Council ◽

Low Dose Radiation ◽

Cochlear Function ◽

High Frequencies ◽

Dose Radiation

AbstractNumerous studies have documented the adverse effects of high-dose radiation on hearing in patients. On the other hand, radiographers are exposed to a low dose of ionizing radiation, and the effect of a low dose of radiation on hearing is quite abstruse. Therefore, the present systematic review aimed to elucidate the effect of low-dose ionizing radiation on hearing. Two authors independently carried out a comprehensive data search in three electronic databases, including PUBMED/MEDLINE, CINAHL, and SCOPUS. Eligible articles were independently assessed for quality by two authors. Cochrane Risk of Bias tool was used assess quality of the included studies. Two articles met the low-dose radiation exposure criteria given by Atomic Energy Regulatory Board (AERB) and National Council on Radiation Protection (NCRP) guidelines. Both studies observed the behavioral symptoms, pure-tone hearing sensitivity at the standard, extended high frequencies, and the middle ear functioning in low-dose radiation-exposed individuals and compared with age and gender-matched controls. One study assessed the cochlear function using transient-evoked otoacoustic emissions (TEOAE). Both studies reported that behavioral symptoms of auditory dysfunction and hearing thresholds at extended high frequencies were higher in radiation-exposed individuals than in the controls. The current systematic review concludes that the low-dose ionizing radiation may affect the hearing adversely. Nevertheless, further studies with robust research design are required to explicate the cause and effect relationship between the occupational low-dose ionizing radiation exposure and hearing.

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Effects of exposure to low-dose ionizing radiation on changing platelets: a prospective cohort study

Environmental Health and Preventive Medicine ◽

10.1186/s12199-021-00939-z ◽

2021 ◽

Vol 26 (1) ◽

Author(s):

Ning Liu ◽

Yang Peng ◽

Xinguang Zhong ◽

Zheng Ma ◽

Suiping He ◽

...

Keyword(s):

Radiation Dose ◽

Ionizing Radiation ◽

Dose Response ◽

Low Dose ◽

Linear Trend ◽

Hematological Parameters ◽

Response Relationship ◽

Dose Response Relationship ◽

Spline Models ◽

Cumulative Radiation Dose

Abstract Background Numerous studies have concentrated on high-dose radiation exposed accidentally or through therapy, and few involve low-dose occupational exposure, to investigate the correlation between low-dose ionizing radiation and changing hematological parameters among medical workers. Methods Using a prospective cohort study design, we collected health examination reports and personal dose monitoring data from medical workers and used Poisson regression and restricted cubic spline models to assess the correlation between changing hematological parameters and cumulative radiation dose and determine the dose-response relationship. Results We observed that changing platelet of 1265 medical workers followed up was statistically different among the cumulative dose groups (P = 0.010). Although the linear trend tested was not statistically significant (Ptrend = 0.258), the non-linear trend tested was statistically significant (Pnon-linear = 0.007). Overall, there was a correlation between changing platelets and cumulative radiation dose (a change of βa 0.008 × 109/L during biennially after adjusting for gender, age at baseline, service at baseline, occupation, medical level, and smoking habits; 95% confidence interval [CI] = 0.003,0.014 × 109/L). Moreover, we also found positive first and then negative dose-response relationships between cumulative radiation dose and changing platelets by restricted cubic spline models, while there were negative patterns of the baseline service not less than 10 years (− 0.015 × 109/L, 95% CI = − 0.024, − 0.007 × 109/L) and radiation nurses(− 0.033 × 109/L, 95% CI = − 0.049, − 0.016 × 109/L). Conclusion We concluded that although the exposure dose was below the limit, medical workers exposed to low-dose ionizing radiation for a short period of time might have increased first and then decreased platelets, and there was a dose-response relationship between the cumulative radiation dose and platelets changing.

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Using a Temperature-Switching Approach to Evaluate Low-Dose-Rate Ionizing Radiation Effects on SET in Linear Bipolar Circuits

IEEE Transactions on Nuclear Science ◽

10.1109/tns.2019.2908959 ◽

2019 ◽

Vol 66 (7) ◽

pp. 1557-1565 ◽

Cited By ~ 1

Author(s):

Shuai Yao ◽

Wu Lu ◽

Xin Yu ◽

Qi Guo ◽

Chengfa He ◽

...

Keyword(s):

Ionizing Radiation ◽

Dose Rate ◽

Radiation Effects ◽

Low Dose ◽

Low Dose Rate

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Ionizing Radiation and Translation Control: A Link to Radiation Hormesis?

International Journal of Molecular Sciences ◽

10.3390/ijms21186650 ◽

2020 ◽

Vol 21 (18) ◽

pp. 6650

Author(s):

Usha Kabilan ◽

Tyson E. Graber ◽

Tommy Alain ◽

Dmitry Klokov

Keyword(s):

Protein Synthesis ◽

Ionizing Radiation ◽

Molecular Mechanisms ◽

Low Dose ◽

Mrna Translation ◽

Cellular Responses ◽

Translation Control ◽

Cis Acting ◽

Radiation Hormesis ◽

Downstream Signaling

Protein synthesis, or mRNA translation, is one of the most energy-consuming functions in cells. Translation of mRNA into proteins is thus highly regulated by and integrated with upstream and downstream signaling pathways, dependent on various transacting proteins and cis-acting elements within the substrate mRNAs. Under conditions of stress, such as exposure to ionizing radiation, regulatory mechanisms reprogram protein synthesis to translate mRNAs encoding proteins that ensure proper cellular responses. Interestingly, beneficial responses to low-dose radiation exposure, known as radiation hormesis, have been described in several models, but the molecular mechanisms behind this phenomenon are largely unknown. In this review, we explore how differences in cellular responses to high- vs. low-dose ionizing radiation are realized through the modulation of molecular pathways with a particular emphasis on the regulation of mRNA translation control.

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