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Thirumal R, Vanchiere C, Bhandari R, Jiwani S, Horswell R, Chu S, Chamaria S, Katikaneni P, Boerma M, Gopinathannair R, Olshansky B, Bailey S, Dominic P. The Inverse Correlation Between the Duration of Lifetime Occupational Radiation Exposure and the Prevalence of Atrial Arrhythmia. Front Cardiovasc Med 2022; 9:863939. [PMID: 35711353 PMCID: PMC9196104 DOI: 10.3389/fcvm.2022.863939] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Accepted: 03/28/2022] [Indexed: 11/13/2022] Open
Abstract
Objective Advancements in fluoroscopy-assisted procedures have increased radiation exposure among cardiologists. Radiation has been linked to cardiovascular complications but its effect on cardiac rhythm, specifically, is underexplored. Methods Demographic, social, occupational, and medical history information was collected from board-certified cardiologists via an electronic survey. Bivariate and multivariable logistic regression analyses were performed to assess the risk of atrial arrhythmias (AA). Results We received 1,478 responses (8.8% response rate) from cardiologists, of whom 85.4% were male, and 66.1% were ≤65 years of age. Approximately 36% were interventional cardiologists and 16% were electrophysiologists. Cardiologists > 50 years of age, with > 10,000 hours (h) of radiation exposure, had a significantly lower prevalence of AA vs. those with ≤10,000 h (11.1% vs. 16.7%, p = 0.019). A multivariable logistic regression was performed and among cardiologists > 50 years of age, exposure to > 10,000 radiation hours was significantly associated with a lower likelihood of AA, after adjusting for age, sex, diabetes mellitus, hypertension, and obstructive sleep apnea (adjusted OR 0.57; 95% CI 0.38-0.85, p = 0.007). The traditional risk factors for AA (age, sex, hypertension, diabetes mellitus, and obstructive sleep apnea) correlated positively with AA in our data set. Cataracts, a well-established complication of radiation exposure, were more prevalent in those exposed to > 10,000 h of radiation vs. those exposed to ≤10,000 h of radiation, validating the dependent (AA) and independent variables (radiation exposure), respectively. Conclusion AA prevalence may be inversely associated with radiation exposure in Cardiologists based on self-reported data on diagnosis and radiation hours. Large-scale prospective studies are needed to validate these findings.
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Affiliation(s)
- Rithika Thirumal
- Department of Internal Medicine, University of Cincinnati, Cincinnati, OH, United States
- School of Medicine, Louisiana State University Health Sciences Center, Shreveport, LA, United States
| | - Catherine Vanchiere
- School of Medicine, Louisiana State University Health Sciences Center, Shreveport, LA, United States
- Department of Internal Medicine, Temple University, Philadelphia, PA, United States
| | - Ruchi Bhandari
- Department of Epidemiology and Biostatistics, West Virginia University, Morgantown, WV, United States
| | - Sania Jiwani
- Department of Internal Medicine, Louisiana State University Health Sciences Center, Shreveport, LA, United States
| | - Ronald Horswell
- Pennington Biomedical Research Center, Louisiana State University, Baton Rouge, LA, United States
| | - San Chu
- Pennington Biomedical Research Center, Louisiana State University, Baton Rouge, LA, United States
| | | | - Pavan Katikaneni
- School of Medicine, Louisiana State University Health Sciences Center, Shreveport, LA, United States
- Center for Cardiovascular Diseases and Sciences, Louisiana State University Health Sciences Center, Shreveport, LA, United States
| | - Marjan Boerma
- Department of Pharmaceutical Sciences, University of Arkansas Medical Center, Little Rock, AK, United States
| | - Rakesh Gopinathannair
- Department of Cardiology, Kansas City Heart Rhythm Institute, Overland Park, KS, United States
| | - Brian Olshansky
- Department of Medicine, University of Iowa Hospitals and Clinics, Iowa City, IA, United States
| | - Steven Bailey
- School of Medicine, Louisiana State University Health Sciences Center, Shreveport, LA, United States
- Department of Internal Medicine, Louisiana State University Health Sciences Center, Shreveport, LA, United States
- Center for Cardiovascular Diseases and Sciences, Louisiana State University Health Sciences Center, Shreveport, LA, United States
| | - Paari Dominic
- School of Medicine, Louisiana State University Health Sciences Center, Shreveport, LA, United States
- Center for Cardiovascular Diseases and Sciences, Louisiana State University Health Sciences Center, Shreveport, LA, United States
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Lypska A, Riabchenko N, Rodionova N, Burdo O. Radiation-induced effects on bone marrow of bank voles inhabiting the Chornobyl exclusion zone. Int J Radiat Biol 2022; 98:1366-1375. [PMID: 35230914 DOI: 10.1080/09553002.2022.2047823] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
PURPOSE To investigate the effects of chronic exposure to low-dose radiation on bone marrow hematopoiesis of bank voles inhabiting the radioactively contaminated territory of the Chornobyl exclusion zone. MATERIALS AND METHODS Animals were collected within the highly radioactive area of the so-called Red Forest located close to the destroyed 4th reactor of the Chornobyl Nuclear Power Plant. Radioecological investigations included evaluation of radiocontamination of soil samples by 90Sr and 137Cs, levels of incorporated radionuclides in animals' bodies and organs, as well as the absorbed dose rates. The study of peripheral blood and bone marrow parameters combined with cytogenetic analysis of bone marrow micronucleated polychromatic erythrocytes and standard metaphase test was carried out. RESULTS The blood system of the exposed animals manifested significant changes in peripheral blood parameters (anaemia and leucocyte formula left shift), ineffective differentiation and maturation of bone marrow cells, particularly relevant to the erythroid and granulocyte pools. Increased yields of bone marrow micronucleated polychromatic erythrocytes and chromosomal aberrations, including dicentrics and Robertsonian fusion-like configurations, were revealed. CONCLUSIONS Observed disturbances in the bone marrow and peripheral blood suggest functional instability and inefficient compensatory and recovery reactions of the blood system of the bank voles from the contaminated areas of the Chornobyl exclusion zone. We assume that they are the consequences both of direct radiation exposure and hereditary pathological changes that have formed in a number of generations inhabiting radioactively contaminated areas.
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Affiliation(s)
- Alla Lypska
- Department of Radiobiology and Radioecology, Institute for Nuclear Research of NAS of Ukraine, Kyiv, Ukraine
| | - Natalia Riabchenko
- Department of Radiobiology and Radioecology, Institute for Nuclear Research of NAS of Ukraine, Kyiv, Ukraine
| | - Natalia Rodionova
- Department of Radiobiology and Radioecology, Institute for Nuclear Research of NAS of Ukraine, Kyiv, Ukraine
| | - Olena Burdo
- Department of Radiobiology and Radioecology, Institute for Nuclear Research of NAS of Ukraine, Kyiv, Ukraine
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Ashoub AH, Abdel-Naby DH, Safar MM, El-Ghazaly MA, Kenawy SA. Ameliorative effect of fractionated low-dose gamma radiation in combination with ellagic acid on nicotine-induced hormonal changes and testicular toxicity in rats. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:23287-23300. [PMID: 33443739 DOI: 10.1007/s11356-020-12334-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2020] [Accepted: 12/30/2020] [Indexed: 06/12/2023]
Abstract
Nicotine is an active pharmacological ingredient in cigarette smoke, which may negatively influence the male reproductive system and fertility. This study aims to investigate the effect of fractionated low-dose radiation (fractionated-LDR) and/or ellagic acid (EA) on nicotine-induced hormonal changes and testicular toxicity in rats. Nicotine was administrated orally (1 mg/kg) for 30 days, afterward, rats were treated with LDR (2 × 0.25 Gy/1-week interval), EA (10 mg/kg, 14 consecutive days p.o.), or a combination of both fractionated-LDR and EA. Rats were sacrificed 24 h after the last dose of treatment, then testes were dissected for histopathology examination, along with some biochemical parameters in serum and testicular tissue were evaluated. Nicotine-induced oxidative stress was evidenced by an increase in testicular thiobarbituric acid reactive substances (TBARS) and a decrease in reduced glutathione (GSH) content. Additionally, the activities of testicular androgenic enzymes were decreased, and the activity of serum lactate dehydrogenase (LDH) was significantly increased. The hormonal changes were verified by a noticeable reduction in follicle-stimulating hormone (FSH), luteinizing hormone (LH), and testosterone serum levels. Histological evaluation revealed that the testicular seminiferous tubules structure was distorted. On the contrary, fractionated-LDR plus EA attenuated the negative changes caused by nicotine observed through biochemical and histological findings. Accordingly, the exposure to fractionated-LDR combined with EA may be a promising candidate for treating hormonal changes and testicular toxicity caused by nicotine.
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Affiliation(s)
- Aliaa H Ashoub
- Department of Drug Radiation Research, National Centre for Radiation Research and Technology (NCRRT), Atomic Energy Authority, 3 Ahmed El-Zomor Street, Nasr City, Cairo, Egypt
| | - Doaa H Abdel-Naby
- Department of Drug Radiation Research, National Centre for Radiation Research and Technology (NCRRT), Atomic Energy Authority, 3 Ahmed El-Zomor Street, Nasr City, Cairo, Egypt
| | - Marwa M Safar
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Cairo University, Kasr El-Aini Street, Cairo, Egypt
- Department of Pharmacology and Biochemistry, Faculty of Pharmacy, The British University in Egypt, Suez Desert Road, El Sherouk City, Egypt
| | - Mona A El-Ghazaly
- Department of Drug Radiation Research, National Centre for Radiation Research and Technology (NCRRT), Atomic Energy Authority, 3 Ahmed El-Zomor Street, Nasr City, Cairo, Egypt
| | - Sanaa A Kenawy
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Cairo University, Kasr El-Aini Street, Cairo, Egypt.
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Huang Q, Chai H, Wang S, Sun Y, Xu W. 0.5‑Gy X‑ray irradiation induces reorganization of cytoskeleton and differentiation of osteoblasts. Mol Med Rep 2021; 23:379. [PMID: 33760136 PMCID: PMC7986016 DOI: 10.3892/mmr.2021.12018] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Accepted: 01/29/2021] [Indexed: 12/02/2022] Open
Abstract
Osteoblasts are sensitive to ionizing radiation. The small GTPase RhoA and its effector Rho-associated protein kinase (ROCK) are critical to several cellular functions, including cytoskeleton reorganization, cell survival, and cell differentiation. However, whether the RhoA/ROCK signaling pathway is involved in the regulation of osteoblast cytoskeleton reorganization and differentiation induced by low-dose X-ray irradiation remains to be determined. The aim of the present study was to investigate the role of the RhoA/ROCK signaling pathway in mediating differentiation of osteoblasts and reorganization of the cytoskeleton under low-dose X-ray irradiation. Osteoblasts were pretreated with the ROCK kinase-specific inhibitor (Y-27632) before exposure to low-dose X-ray irradiation. The changes of F-actin in MC3T3 cells were observed at different time points following X-ray irradiation. Cell Counting Kit-8 assay, alkaline phosphatase activity, Alizarin red staining and western blotting were used to detect the proliferation and differentiation of osteoblasts after 0.5-Gy X-ray irradiation. In the present study, low-dose X-ray irradiation promoted the expression of genes associated with the cytoskeleton reorganization. Indeed, the results showed that, 0.5-Gy X-ray irradiation can induce reorganization of cytoskeleton and promote differentiation of osteoblasts through the RhoA/ROCK signaling pathway. Additionally, inhibiting ROCK activity blocked low-dose X-ray irradiation-induced LIMK2 phosphorylation, stress fiber formation and cell differentiation. Thus, these results demonstrated the excitatory effects of low-dose X-ray irradiation on MC3T3-E1 cells, including reorganization of the cytoskeleton and differentiation of osteoblasts.
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Affiliation(s)
- Qun Huang
- Department of Orthopedics, The Second Affiliated Hospital of Soochow University, Suzhou, Jiangsu 215004, P.R. China
| | - Hao Chai
- Department of Orthopedics, The Second Affiliated Hospital of Soochow University, Suzhou, Jiangsu 215004, P.R. China
| | - Shendong Wang
- Department of Orthopedics, The Second Affiliated Hospital of Soochow University, Suzhou, Jiangsu 215004, P.R. China
| | - Yongming Sun
- Department of Orthopedics, The Second Affiliated Hospital of Soochow University, Suzhou, Jiangsu 215004, P.R. China
| | - Wei Xu
- Department of Orthopedics, The Second Affiliated Hospital of Soochow University, Suzhou, Jiangsu 215004, P.R. China
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Jin S, Jiang H, Cai L. New understanding of the low-dose radiation-induced hormesis. RADIATION MEDICINE AND PROTECTION 2020. [DOI: 10.1016/j.radmp.2020.01.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
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Allison RR. Radiobiological modifiers in clinical radiation oncology: current reality and future potential. Future Oncol 2015; 10:2359-79. [PMID: 25525845 DOI: 10.2217/fon.14.174] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Radiation therapy can successfully ablate tumors. However, the same ionization process that destroys a cancer can also permanently damage surrounding organs resulting in unwanted clinical morbidity. Therefore, modern radiation therapy attempts to minimize dose to normal tissue to prevent side effects. Still, as tumors and normal tissues intercalate, the risk of normal tissue injury often may prevent tumoricidal doses of radiation therapy to be delivered. This paper will review current outcomes and limitations of radiobiological modifiers that may selectively enhance the radiosensitivity of tumors as well as parallel techniques that may protect normal tissues from radiation injury. Future endeavors based in part upon newly elucidated genetic pathways will be highlighted.
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Jin C, Qin L, Shi Y, Candas D, Fan M, Lu CL, Vaughan ATM, Shen R, Wu LS, Liu R, Li RF, Murley JS, Woloschak G, Grdina DJ, Li JJ. CDK4-mediated MnSOD activation and mitochondrial homeostasis in radioadaptive protection. Free Radic Biol Med 2015; 81:77-87. [PMID: 25578653 PMCID: PMC4359946 DOI: 10.1016/j.freeradbiomed.2014.12.026] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/23/2014] [Revised: 12/20/2014] [Accepted: 12/28/2014] [Indexed: 01/08/2023]
Abstract
Mammalian cells are able to sense environmental oxidative and genotoxic conditions such as the environmental low-dose ionizing radiation (LDIR) present naturally on the earth's surface. The stressed cells then can induce a so-called radioadaptive response with an enhanced cellular homeostasis and repair capacity against subsequent similar genotoxic conditions such as a high dose radiation. Manganese superoxide dismutase (MnSOD), a primary mitochondrial antioxidant in mammals, has long been known to play a crucial role in radioadaptive protection by detoxifying O2(•-) generated by mitochondrial oxidative phosphorylation. In contrast to the well-studied mechanisms of SOD2 gene regulation, the mechanisms underlying posttranslational regulation of MnSOD for radioprotection remain to be defined. Herein, we demonstrate that cyclin D1/cyclin-dependent kinase 4 (CDK4) serves as the messenger to deliver the stress signal to mitochondria to boost mitochondrial homeostasis in human skin keratinocytes under LDIR-adaptive radioprotection. Cyclin D1/CDK4 relocates to mitochondria at the same time as MnSOD enzymatic activation peaks without significant changes in total MnSOD protein level. The mitochondrial-localized CDK4 directly phosphorylates MnSOD at serine-106 (S106), causing enhanced MnSOD enzymatic activity and mitochondrial respiration. Expression of mitochondria-targeted dominant negative CDK4 or the MnSOD-S106 mutant reverses LDIR-induced mitochondrial enhancement and adaptive protection. The CDK4-mediated MnSOD activation and mitochondrial metabolism boost are also detected in skin tissues of mice receiving in vivo whole-body LDIR. These results demonstrate a unique CDK4-mediated mitochondrial communication that allows cells to sense environmental genotoxic stress and boost mitochondrial homeostasis by enhancing phosphorylation and activation of MnSOD.
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Affiliation(s)
- Cuihong Jin
- Department of Radiation Oncology, University of California at Davis School of Medicine, Sacramento, CA 95817, USA
| | - Lili Qin
- Department of Radiation Oncology, University of California at Davis School of Medicine, Sacramento, CA 95817, USA
| | - Yan Shi
- Department of Radiation Oncology, University of California at Davis School of Medicine, Sacramento, CA 95817, USA
| | - Demet Candas
- Department of Radiation Oncology, University of California at Davis School of Medicine, Sacramento, CA 95817, USA
| | - Ming Fan
- Department of Radiation Oncology, University of California at Davis School of Medicine, Sacramento, CA 95817, USA
| | - Chung-Ling Lu
- Department of Radiation Oncology, University of California at Davis School of Medicine, Sacramento, CA 95817, USA
| | - Andrew T M Vaughan
- Department of Radiation Oncology, University of California at Davis School of Medicine, Sacramento, CA 95817, USA
| | - Rulong Shen
- Department of Pathology, Ohio State University Medical College, Columbus, OH 43210, USA
| | - Larry S Wu
- Department of Radiation Oncology, University of California at Davis School of Medicine, Sacramento, CA 95817, USA
| | - Rui Liu
- Department of Radiation Oncology, University of California at Davis School of Medicine, Sacramento, CA 95817, USA
| | - Robert F Li
- Department of Radiation Oncology, University of California at Davis School of Medicine, Sacramento, CA 95817, USA
| | - Jeffrey S Murley
- Department of Radiation and Cellular Oncology, University of Chicago, Chicago, IL 60637, USA
| | - Gayle Woloschak
- Department of Radiation Oncology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - David J Grdina
- Department of Radiation and Cellular Oncology, University of Chicago, Chicago, IL 60637, USA
| | - Jian Jian Li
- Department of Radiation Oncology, University of California at Davis School of Medicine, Sacramento, CA 95817, USA; NCI-Designated Comprehensive Cancer Center, University of California at Davis Health System, Sacramento, CA, 95817, USA.
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Zhao Y, Zhong R, Sun L, Jia J, Ma S, Liu X. Ionizing radiation-induced adaptive response in fibroblasts under both monolayer and 3-dimensional conditions. PLoS One 2015; 10:e0121289. [PMID: 25807079 PMCID: PMC4373882 DOI: 10.1371/journal.pone.0121289] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2014] [Accepted: 01/29/2015] [Indexed: 01/01/2023] Open
Abstract
To observe the adaptive response (AR) induced by ionizing radiation in human fibroblasts under monolayer and 3-dimensional (3-D) condition. Three kinds of fibroblasts were cultured under both monolayer and 3-D condition. Immunofluorescent staining was used to detect the γ-H2AX foci and the morphological texture. Trypan blue staining was used to detect the cell death. Western blot was used to detect the expressions of γ-H2AX, p53 and CDKN1A/p21 (p21). We found that DNA damage increased in a dose-dependent and time-dependent manner after high doses of radiation. When cells were pretreated with a priming low dose of radiation followed by high dose radiation, DNA damage was attenuated under both monolayer and 3-D condition, and the adaptive response (AR) was induced. Additionally, the morphology of cells under monolayer and 3-D conditions were different, and radiation also induced AR according to morphological texture analysis. Priming low dose radiation induced AR both under monolayer and 3-D condition. Interestingly, 3-D microenvironment made cells more sensitive to radiation. The expression of p53 and p21 was changed and indicated that they might participate in the regulation of AR.
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Affiliation(s)
- Yinlong Zhao
- Key Laboratory of Radiobiology (Ministry of Health), School of Public Health, Jilin University, Changchun, China
- Dept. Nuclear Medicine, 2nd Hospital Jilin University, Changchun, China
| | - Rui Zhong
- Key Laboratory of Radiobiology (Ministry of Health), School of Public Health, Jilin University, Changchun, China
| | - Liguang Sun
- Dept. Translational Medicine, 1st Hospital Jilin University, Changchun, China
| | - Jie Jia
- Dept. Ultrasound, China-Japan Union Hospital, Changchun, China
| | - Shumei Ma
- Key Laboratory of Radiobiology (Ministry of Health), School of Public Health, Jilin University, Changchun, China
- * E-mail: (SM); (XL)
| | - Xiaodong Liu
- Key Laboratory of Radiobiology (Ministry of Health), School of Public Health, Jilin University, Changchun, China
- * E-mail: (SM); (XL)
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Wang B, Li B, Dai Z, Ren S, Bai M, Wang Z, Li Z, Lin S, Wang Z, Huang N, Yang P, Liu M, Min W, Ma H. Low-dose splenic radiation inhibits liver tumor development of rats through functional changes in CD4+CD25+Treg cells. Int J Biochem Cell Biol 2014; 55:98-108. [PMID: 25168696 DOI: 10.1016/j.biocel.2014.08.014] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2014] [Revised: 07/27/2014] [Accepted: 08/17/2014] [Indexed: 02/07/2023]
Abstract
The increased number of CD4(+)CD25(+)Treg cells in tumor local and peripheral splenic tissues is related to the low immune function as well as to tumor recurrence and metastasis. Our pre-clinical studies showed that low-dose radiation (LDR) of the spleen in liver cancer patients significantly improves immune functions. However, the molecular mechanisms of such radiation remained ill defined. This study explores the role of CD4(+)CD25(+)Treg cells in radiation-induced immunomodulatory effects. Using the diethylnitrosamine (DEN)-induced rat liver tumor model and in vitro cell experiments, the percentage of CD4(+)CD25(+)Treg/CD4(+) cells in the blood and the expressions of Foxp3(+), IL-10, TGF-β, and cytotoxic T lymphocyte-associated antigen-4(CTLA-4) in spleen and liver tumors significantly decreased after LDR of the spleen in rats with liver cancer. The tumors became smaller than those in the non-radiated group, with both showing a parallel relation. Flow cytometry and MTT results revealed that LDR failed to inhibit CD4(+)CD25(+)Treg cell proliferation. Conversely, apoptosis was reduced and proliferation was stimulated. This process also changed CTLA-4 molecule expression on the surfaces of CD4(+)CD25(+)Treg cells and reduced their inhibitory function against CD4(+)CD25(-)T cell proliferation, and the suppression function of CD4(+)CD25(+)Treg cells was further weakened with the introduction of the CTLA-4 inhibitor. Findings demonstrate that the reduction of CTLA-4 expression on the CD4(+)CD25(+)Treg cell surface and the further inhibition of cell function may be considered as important regulators of LDR-induced immunomodulatory effects. This study provides experimental evidence to elucidate the immune enhancement induced by this process and presents a novel method for liver cancer immunotherapy.
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Affiliation(s)
- Baofeng Wang
- Department of Oncology, The Second Affiliated Hospital of School of Medicine, Xi'an Jiaotong University, Xi'an 710004, PR China.
| | - Baohua Li
- Department of Surgery, The Second Affiliated Hospital of School of Medicine, Xi'an Jiaotong University, Xi'an 710004, PR China.
| | - Zhijun Dai
- Department of Oncology, The Second Affiliated Hospital of School of Medicine, Xi'an Jiaotong University, Xi'an 710004, PR China.
| | - Song Ren
- Department of Surgery, The Second Affiliated Hospital of School of Medicine, Xi'an Jiaotong University, Xi'an 710004, PR China.
| | - Minghua Bai
- Department of Oncology, The Second Affiliated Hospital of School of Medicine, Xi'an Jiaotong University, Xi'an 710004, PR China.
| | - Zhongwei Wang
- Department of Oncology, The Second Affiliated Hospital of School of Medicine, Xi'an Jiaotong University, Xi'an 710004, PR China.
| | - Zongfang Li
- Department of Surgery, The Second Affiliated Hospital of School of Medicine, Xi'an Jiaotong University, Xi'an 710004, PR China.
| | - Shuai Lin
- Department of Oncology, The Second Affiliated Hospital of School of Medicine, Xi'an Jiaotong University, Xi'an 710004, PR China.
| | - Zhidong Wang
- Department of Surgery, The Second Affiliated Hospital of School of Medicine, Xi'an Jiaotong University, Xi'an 710004, PR China.
| | - Na Huang
- Department of Surgery, The Second Affiliated Hospital of School of Medicine, Xi'an Jiaotong University, Xi'an 710004, PR China.
| | - Pengtao Yang
- Department of Oncology, The Second Affiliated Hospital of School of Medicine, Xi'an Jiaotong University, Xi'an 710004, PR China.
| | - Mengjie Liu
- Department of Oncology, The First Affiliated Hospital of School of Medicine, Xi'an Jiaotong University, Xi'an 710061, PR China.
| | - Weili Min
- Department of Oncology, The Second Affiliated Hospital of School of Medicine, Xi'an Jiaotong University, Xi'an 710004, PR China.
| | - Hongbing Ma
- Department of Oncology, The Second Affiliated Hospital of School of Medicine, Xi'an Jiaotong University, Xi'an 710004, PR China.
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Joyce M, McEntee M, Brennan PC, O’Leary D. Reducing Dose for Digital Cranial Radiography: The Increased Source to the Image-receptor Distance Approach. J Med Imaging Radiat Sci 2013; 44:180-187. [DOI: 10.1016/j.jmir.2013.07.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2013] [Revised: 07/02/2013] [Accepted: 07/04/2013] [Indexed: 11/16/2022]
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Gridley DS, Mao XW, Cao JD, Bayeta EJM, Pecaut MJ. Protracted low-dose radiation priming and response of liver to acute gamma and proton radiation. Free Radic Res 2013; 47:811-20. [DOI: 10.3109/10715762.2013.826351] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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Abstract
The atomic bomb survivor cancer mortality data have been used in the past to justify the use of the linear no-threshold (LNT) model for estimating the carcinogenic effects of low dose radiation. An analysis of the recently updated atomic bomb survivor cancer mortality dose-response data shows that the data no longer support the LNT model but are consistent with a radiation hormesis model when a correction is applied for a likely bias in the baseline cancer mortality rate. If the validity of the phenomenon of radiation hormesis is confirmed in prospective human pilot studies, and is applied to the wider population, it could result in a considerable reduction in cancers. The idea of using radiation hormesis to prevent cancers was proposed more than three decades ago, but was never investigated in humans to determine its validity because of the dominance of the LNT model and the consequent carcinogenic concerns regarding low dose radiation. Since cancer continues to be a major health problem and the age-adjusted cancer mortality rates have declined by only ∼10% in the past 45 years, it may be prudent to investigate radiation hormesis as an alternative approach to reduce cancers. Prompt action is urged.
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Cohen SA, Rangarajan SS, Chen T, Palazzi KL, Langford JS, Sur RL. Occupational hazard: radiation exposure for the urologist--developing a reference standard. Int Braz J Urol 2013; 39:209-13. [PMID: 23683685 DOI: 10.1590/s1677-5538.ibju.2013.02.09] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2012] [Accepted: 01/30/2013] [Indexed: 11/22/2022] Open
Abstract
INTRODUCTION To date, there is a paucity of literature offering practicing urologists a reference for the amount of radiation exposure received while surgically managing urolithiasis. This study examines the cumulative radiation exposure of an urologist over 9 months. MATERIALS AND METHODS We present a case series of fluoroscopic exposures of an experienced stone surgeon operating at an academic comprehensive stone center between April and December 2011. Radiation exposure measurements were determined by a thermoluminescent dosimeter worn on the outside of the surgeon's thyroid shield. Estimations of radiation exposure (mrem) per month were charted with fluoroscopy times, using scatter plots to estimate Spearman's rank correlation coefficients. RESULTS The total 9-month radiation exposure was 87 mrems for deep dose equivalent (DDE), 293 mrem for lens dose equivalent (LDE), and 282 mrem for shallow dose equivalent (SDE). Total fluoroscopy time was 252.44 minutes for 64 ureteroscopies (URSs), 29 percutaneous nephrolithtomies (PNLs), 20 cystoscopies with ureteral stent placements, 9 shock wave lithotripsies (SWLs), 9 retrograde pyelograms (RPGs), 2 endoureterotomies, and 1 ureteral balloon dilation. Spearman's rank correlation coefficients examining the association between fluoroscopy time and radiation exposure were not significant for DDE (p = 0.6, Spearman's rho = 0.2), LDE (p = 0.6, Spearman's rho = 0.2), or SDE (p = 0.6, Spearman's rho = 0.2). CONCLUSIONS Over a 9-month period, total radiation exposures were well below annual accepted limits (DDE 5000 mrem, LDE 15,000 mrem and SDE 50,000 mrem). Although fluoroscopy time did not correlate with radiation exposure, future prospective studies can account for co-variates such as patient obesity and urologist distance from radiation source.
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Affiliation(s)
- Seth A Cohen
- Department of Surgery and Division of Urology, U C San Diego Health Science System, San Diego, CA, USA
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Franzese O, Tricarico M, Starace G, Pepponi R, Bonmassar L, Cottarelli A, Fuggetta MP. Interferon-Beta combined with interleukin-2 restores human natural cytotoxicity impaired in vitro by ionizing radiations. J Interferon Cytokine Res 2013; 33:308-18. [PMID: 23421371 DOI: 10.1089/jir.2012.0025] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
It is well known that ionizing radiations induce a marked downregulation of antigen-dependent and natural immunity for a prolonged period of time. This is due, at least in part, to radiation-induced apoptosis of different lymphocyte subpopulations, including natural killer (NK) cells. Aim of this study was to investigate the capability of Beta Interferon (β-IFN) and Interleukin-2 (IL2), alone or in combination, to restore the functional activity of the natural immune system. Mononuclear cells (MNCs) obtained from intact or in vitro irradiated human peripheral blood were treated in vitro with β-IFN immediately before or at the end of the 4-day treatment with IL2. Time-course analysis was performed on the NK activity, the total number and the apoptotic fraction of CD16+ and CD56+ cells, the 2 main NK effector cell subpopulations. The results indicate that radiation-induced impairment of natural cytotoxicity of MNC could be successfully antagonized by the β-IFN+IL2 combination, mainly when exposure to β-IFN preceded IL2 treatment. This radioprotective effect is paralleled by lower levels of radiation-induced apoptosis and increased expression of the antiapoptotic Bcl-2 protein. Since natural immunity can play a significant role in antitumor host's resistance, these results could provide the rational basis for a cytokine-based pharmacological strategy able to restore immune responsiveness and to afford possible therapeutic benefits in cancer patients undergoing radiotherapy.
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Affiliation(s)
- Ornella Franzese
- Department of Neuroscience, Chair of Pharmacology, School of Medicine, University of Rome Tor Vergata, Rome, Italy
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15
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Gridley DS, Rizvi A, Makinde AY, Luo-Owen X, Mao XW, Tian J, Slater JM, Pecaut MJ. Space-relevant radiation modifies cytokine profiles, signaling proteins and Foxp3+T cells. Int J Radiat Biol 2012; 89:26-35. [DOI: 10.3109/09553002.2012.715792] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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Abstract
PURPOSE To review the cellular mechanisms of hormetic effects induced by low dose and low dose rate ionising radiation in model systems, and to call attention to the possible role of autophagy in some hormetic effects. RESULTS AND CONCLUSIONS Very low radiation doses stimulate cell proliferation by changing the equilibrium between the phosphorylated and dephosphorylated forms of growth factor receptors. Radioadaptation is induced by various weak stress stimuli and depends on signalling events that ultimately decrease the molecular damage expression at the cellular level upon subsequent exposure to a moderate radiation dose. Ageing and cancer result from oxidative damage under oxidative stress conditions; nevertheless, ROS are also prominent inducers of autophagy, a cellular process that has been shown to be related both to ageing retardation and cancer prevention. A balance between the signalling functions and damaging effects of ROS seems to be the most important factor that decides the fate of the mammalian cell when under oxidative stress conditions, after exposure to ionising radiation. Not enough is yet known on the pre-requirements for maintaining such a balance. Given the present stage of investigation into radiation hormesis, the application of the conclusions from experiments on model systems to the radiation protection regulations would not be justified.
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Affiliation(s)
- Irena Szumiel
- Centre for Radiobiology and Biological Dosimetry, Institute of Nuclear Chemistry and Technology, Warsaw, Poland.
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Koukourakis MI. Radiation damage and radioprotectants: new concepts in the era of molecular medicine. Br J Radiol 2012; 85:313-30. [PMID: 22294702 DOI: 10.1259/bjr/16386034] [Citation(s) in RCA: 91] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Exposure to ionising radiation results in mutagenesis and cell death, and the clinical manifestations depend on the dose and the involved body area. Reducing carcinogenesis in patients treated with radiotherapy, exposed to diagnostic radiation or who are in certain professional groups is mandatory. The prevention or treatment of early and late radiotherapy effects would improve quality of life and increase cancer curability by intensifying therapies. Experimental and clinical data have given rise to new concepts and a large pool of chemical and molecular agents that could be effective in the protection and treatment of radiation damage. To date, amifostine is the only drug recommended as an effective radioprotectant. This review identifies five distinct types of radiation damage (I, cellular depletion; II, reactive gene activation; III, tissue disorganisation; IV, stochastic effects; V, bystander effects) and classifies the radioprotective agents into five relevant categories (A, protectants against all types of radiation effects; B, death pathway modulators; C, blockers of inflammation, chemotaxis and autocrine/paracrine pathways; D, antimutagenic keepers of genomic integrity; E, agents that block bystander effects). The necessity of establishing and funding central committees that guide systematic clinical research into evaluating the novel agents revealed in the era of molecular medicine is stressed.
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Affiliation(s)
- M I Koukourakis
- Department of Radiotherapy and Oncology, Democritus University of Thrace, Alexandroupolis, Greece.
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Mozdarani H. Biological complexities in radiation carcinogenesis and cancer radiotherapy: impact of new biological paradigms. Genes (Basel) 2012; 3:90-114. [PMID: 24704845 PMCID: PMC3899963 DOI: 10.3390/genes3010090] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2011] [Revised: 01/07/2012] [Accepted: 01/13/2012] [Indexed: 12/31/2022] Open
Abstract
Although radiation carcinogenesis has been shown both experimentally and epidemiologically, the use of ionizing radiation is also one of the major modalities in cancer treatment. Various known cellular and molecular events are involved in carcinogenesis. Apart from the known phenomena, there could be implications for carcinogenesis and cancer prevention due to other biological processes such as the bystander effect, the abscopal effect, intrinsic radiosensitivity and radioadaptation. Bystander effects have consequences for mutation initiated cancer paradigms of radiation carcinogenesis, which provide the mechanistic justification for low-dose risk estimates. The abscopal effect is potentially important for tumor control and is mediated through cytokines and/or the immune system (mainly cell-mediated immunity). It results from loss of growth and stimulatory and/or immunosuppressive factors from the tumor. Intrinsic radiosensitivity is a feature of some cancer prone chromosomal breakage syndromes such as ataxia telangectiasia. Radiosensitivity is manifested as higher chromosomal aberrations and DNA repair impairment is now known as a good biomarker for breast cancer screening and prediction of prognosis. However, it is not yet known whether this effect is good or bad for those receiving radiation or radiomimetic agents for treatment. Radiation hormesis is another major concern for carcinogenesis. This process which protects cells from higher doses of radiation or radio mimic chemicals, may lead to the escape of cells from mitotic death or apoptosis and put cells with a lower amount of damage into the process of cancer induction. Therefore, any of these biological phenomena could have impact on another process giving rise to genome instability of cells which are not in the field of radiation but still receiving a lower amount of radiation. For prevention of radiation induced carcinogenesis or risk assessment as well as for successful radiation therapy, all these phenomena should be taken into account.
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Affiliation(s)
- Hossein Mozdarani
- Department of Medical Genetics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran P.O. Box 14115-111, Iran.
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Elhajouji A, Lukamowicz M, Cammerer Z, Kirsch-Volders M. Potential thresholds for genotoxic effects by micronucleus scoring. Mutagenesis 2010; 26:199-204. [DOI: 10.1093/mutage/geq089] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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