DOCSLIB.ORG

Is the Linear No-Threshold Dose-Response Paradigm Still Necessary for the Assessment of Health Effects of Low Dose Radiation?

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Is the Linear No-Threshold Dose-Response Paradigm Still Necessary for the Assessment of Health Effects of Low Dose Radiation? SPECIAL ARTICLE http://dx.doi.org/10.3346/jkms.2016.31.S1.S10 • J Korean Med Sci 2016; 31: S10-23 Is the Linear No-Threshold Dose-Response Paradigm Still Necessary for the Assessment of Health Effects of Low Dose Radiation? Ki Moon Seong,* Songwon Seo,* Inevitable human exposure to ionizing radiation from man-made sources has been Dalnim Lee, Min-Jeong Kim, increased with the proceeding of human civilization and consequently public concerns Seung-Sook Lee, Sunhoo Park, focus on the possible risk to human health. Moreover, Fukushima nuclear power plant and Young Woo Jin accidents after the 2011 East-Japan earthquake and tsunami has brought the great fear and anxiety for the exposure of radiation at low levels, even much lower levels similar to Laboratory of Radiation Exposure & Therapeutics, natural background. Health effects of low dose radiation less than 100 mSv have been National Radiation Emergency Medical Center, Korea Institute of Radiological & Medical Sciences, debated whether they are beneficial or detrimental because sample sizes were not large Seoul, Korea enough to allow epidemiological detection of excess effects and there was lack of consistency among the available experimental data. We have reviewed an extensive * Ki Moon Seong and Songwon Seo equally literature on the low dose radiation effects in both radiation biology and epidemiology, contributed to this work. and highlighted some of the controversies therein. This article could provide a reasonable Received: 22 June 2015 view of utilizing radiation for human life and responding to the public questions about Accepted: 17 September 2015 radiation risk. In addition, it suggests the necessity of integrated studies of radiobiology and epidemiology at the national level in order to collect more systematic and profound Address for Correspondence: Young Woo Jin, MD information about health effects of low dose radiation. National Radiation Emergency Medical Center, Korea Institute of Radiological & Medical Sciences, 75 Nowon-ro, Nowon-gu, Seoul 01812, Korea Keywords: Low Dose Radiation; Health Effects; Radiobiology; Epidemiology; LNT Model E-mail: [email protected] Funding: This work was supported by the Nuclear Safety Research Program through the Korea Radiation Safety Foundation, granted financial resource from the Nuclear Safety and Security Commission (NSSC) (No. 1303028), and the Ministry of Science, ICT and Future Planning (MSIP) (No. 50586-2015), Republic of Korea. INTRODUCTION RADIATION EXPOSURE AND BIOLOGICAL RESPONSE Since the discoveries of X-ray by Roentgen, W.C. in 1895 and radioactivity by Becquerel, H. in 1896 (1), radiation has been Challenge to the target theory in low dose radiation used in diverse fields for the improvement of human life, in- response cluding medical diagnosis and treatment for diseases, industri- Despite the uncertainty of the Muller’s data due to insufficient al application, scientific and educational uses (2). In the early analysis and lack of overall consistent findings for low dose days after finding radiation, it was prevalent all over the indus- range, his achievement is one of the critical contributing factors trial fields without recognizing that exposure to large radiation consolidating linear-no-threshold (LNT) model as a standard dose could cause serious harmful effects on human health, for concept for regulation of the human radiation exposure (5,6). example, “Radiothor” (a popular and expensive radium con- In the LNT model, any low dose of radiation can dose-propor- taining water) and “Fluoroscope” (a shoe-fitting X-ray unit) (3). tionally cause detrimental effects such as cancer and heritable Owing to the scientific research such as Herman J. Muller’s pio- genetic mutation without a threshold dose. This model is now neering works on the mutagenic X-ray and the radiation disas- accepted to adopt policy for radiation protection in the world ter by two atomic bombs in 1945 in Japan, the view of the public (7). However, the LNT model neglects the important facts that for the radiation had been changed, and finally the protection all living beings on the earth have been evolved and adapted to standards for exposure to radiation was constructed by several harsher natural radiation environments for billions of years. expert authorities (4). Moreover, there is a growing body of experimental and epide- miological evidence that does not support the LNT model for © 2016 The Korean Academy of Medical Sciences. pISSN 1011-8934 This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. eISSN 1598-6357 Seong KM, et al. • Linear No-Threshold Dose-Response in Low Dose Radiation estimating cancer risks at low doses (8). In addition, the tradi- is not absolute. Deterministic effects can occur as a result from tional concept that radiation hits a defined target in cells and the loss of normally functioning large number of critical cells genes has been changed into that there are also non-targeted caused by stochastic killing of irradiated individual cells. DNA mechanisms in low dose radiation response. They are very complex to investigate, and the prediction for their occurrence RISK ASSESSMENT OF RADIATION EXPOSURE is more difficult due to the presence of several agonistic or an- tagonistic confounding factors such as pollutants, ages and life Proposed models for risk assessment of radiation styles. Recent reports issued by international authorities of radi- exposure and ongoing debate ation such as the National Academy of Sciences (NAS), the Unit- During the early decades of the 20th century, consensus of the ed Nations Scientific Committee on the Effects of Atomic Radi- public had been achieved that the most fundamental radiation ation (UNSCEAR), the International Commission on Radiologi- dose-response relationships have a threshold (16). Protection cal Protection (ICRP), the French Academy of Sciences (FAS) agencies recommended dose limits for workers and the public analyzed a great number of experimental data related to low following linear model with a threshold dose. They believed the dose radiation (9-12). They commonly announced that biologi- presence of tolerance levels against radiation exposure. In this cal responses of low dose radiation were different from those of model, there is no radiation risk at less than a threshold dose. high dose radiation with various dose-response relationships However, this concept was rapidly changed after atomic bomb and therefore, low dose effects cannot be concluded to be harm- disaster. The atomic bomb survivor data and several evidence ful to human health (9,12). They also recommended holistic from various medical exposure groups had successively re- approaches combining biological system-based methods with duced the recommended dose limit over the years (13). For the epidemiological data to develop more sophisticated dose-re- protection against radiation exposure, the dose-response mod- sponse models at low dose levels, considering a dose and dose- el was finally replaced with a conservative model with the LNT rate effectiveness factor (DDREF) (7). hypothesis that there is no threshold to induce radiation re- sponse (17). This model was accepted for human protection of Complexity of biological effects of radiation exposure radiation exposure and published as a guideline of radiation Radiation may damage various cellular components including policy by ICRP (18). The LNT hypothesis was very useful to esti- DNA, directly (molecule ionization) or indirectly (reactive oxy- mate the risk of radiation exposure at high doses based on the gen species production). Irradiated cells protect themselves by solid scientific evidence, but not at low doses since the data at many innate defense mechanisms such as removal of oxidative low doses are imprecise and often conflicting. A great deal of stress and damaged cells, and DNA repair. Remained damages research has been performed to establish dose-response rela- of cells may cause tissue/organ dysfunction and malignant dis- tionships, especially, in low dose range using data including eases. For radiation protection, the biological effects of radia- Japanese atomic bomb survivors, cancer and life-shortening in tion are conventionally categorized into two broad classes: sto- animals, chromosome aberrations in somatic cells, and then chastic and deterministic effects (or recently termed tissue re- other risk assessment models has been proposed to estimate actions) (13). the radiation toxicity in low levels (19). Nowadays, five risk as- Stochastic effects have probability of occurrence depending sessment models has been discussed (Fig. 1). These models fo- on the irradiated doses without threshold. These effects can -oc cus on primarily cancer risk. Regarding heritable risk, its nomi- cur by chance and consist primarily of cancer and genetic ef- nal risk coefficient in the whole population was estimated as fects such as inherited mutations. Stochastic effects often show 0.2% per Sv in ICRP 103, which was substantially reduced by a up years after exposure. In addition, because they can occur in factor of 6-8 compared to the estimates from the former ICRP individuals under background radiation levels without expo- 60, becoming less of a concern about health risks of low dose sure, it can never be determined
Load more

Recommended publications
  • Eroticism As a Hormetic Stimulus in Health and Ageing
    Central JSM Sexual Medicine Bringing Excellence in Open Access Review Article *Corresponding author Marios Kyriazis, National Gerontology Centre, 35 Karaoli & Demetriou Street, Larnaca 6021, Cyprus, Email: Eroticism as a Hormetic Submitted: 13 December 2018 Accepted: 27 December 2018 Stimulus in Health and Ageing Published: 31 December 2018 Marios Kyriazis* ISSN: 2578-3718 Copyright National Gerontology Centre, Cyprus © 2018 Kyriazis Abstract OPEN ACCESS Eroticism in later life is, on the whole, a taboo subject, and the stigma attached to expressions Keywords of sexual intent by older people is widespread in most cultures. However, sexuality and eroticism • Sexuality have an important role to play in maintaining healthy ageing. Sexuality is an essential aspect • Eroticism of our biology and its effects have repercussions in systems and organs other than the sexual. • Hormesis In this paper I review the importance of developing a sexual-erotic element in later life, an • Biological amplification element that is intimately coupled with the phenomenon of hormesis. In hormesis, there is biological • Cognition benefit following exposure to a mild stimulus or challenge, whereas exposure to a higher dose of • Healthy human ageing the same stimulus becomes detrimental. Innovative sexual stimulation can be seen as a hormetic opportunity to initiate beneficial effects on the entire ageing human organism. The intention is to show that, health benefits may be obtained not only through physical (exercise), nutritional, mental or pharmacological challenges, but also through sexual stimulation of the appropriate magnitude and quality. By enhancing erotic stimulation it may be possible to experience many other benefits spanning several domains such as the endocrine, immune, circulatory and neurological.
    [Show full text]
  • The Overestimation of Medical Consequences of Low-Dose Exposure to Ionizing Radiation
    The Overestimation of Medical Consequences of Low-Dose Exposure to Ionizing Radiation The Overestimation of Medical Consequences of Low-Dose Exposure to Ionizing Radiation By Sergei V. Jargin The Overestimation of Medical Consequences of Low-Dose Exposure to Ionizing Radiation By Sergei V. Jargin This book first published 2019 Cambridge Scholars Publishing Lady Stephenson Library, Newcastle upon Tyne, NE6 2PA, UK British Library Cataloguing in Publication Data A catalogue record for this book is available from the British Library Copyright © 2019 by Sergei V. Jargin All rights for this book reserved. No part of this book may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, without the prior permission of the copyright owner. ISBN (10): 1-5275-2672-0 ISBN (13): 978-1-5275-2672-3 In memory of my father Vadim S. Yargin (1923-2012), co-author of the “Handbook of Physical Properties of Liquids and Gases” edited by Begell House. TABLE OF CONTENTS Introduction ................................................................................................ 1 Chapter One ................................................................................................ 3 Hormesis and Radiation Safety Norms Chapter Two ............................................................................................. 23 Dose and Dose Rate Effectiveness Factor (DDREF) Chapter Three ..........................................................................................
    [Show full text]
  • NUCLEAR ENERGY and HEALTH and the Benefits of Low-Dose Radiation Hormesis Jerry M Cuttler Cuttler & Associates Inc., Mississauga, ON, Canada
    Dose-Response: An International Journal Volume 7 | Issue 1 Article 3 3-2009 NUCLEAR ENERGY AND HEALTH And the Benefits of Low-Dose Radiation Hormesis Jerry M Cuttler Cuttler & Associates Inc., Mississauga, ON, Canada Myron Pollycove University of California San Francisco, San Francisco, CA Follow this and additional works at: https://scholarworks.umass.edu/dose_response Recommended Citation Cuttler, Jerry M and Pollycove, Myron (2009) "NUCLEAR ENERGY AND HEALTH And the Benefits of Low-Dose Radiation Hormesis," Dose-Response: An International Journal: Vol. 7 : Iss. 1 , Article 3. Available at: https://scholarworks.umass.edu/dose_response/vol7/iss1/3 This Article is brought to you for free and open access by ScholarWorks@UMass Amherst. It has been accepted for inclusion in Dose-Response: An International Journal by an authorized editor of ScholarWorks@UMass Amherst. For more information, please contact [email protected]. Cuttler and Pollycove: Nuclear energy and health Dose-Response, 7:52–89, 2009 InternationalDOSE-RESPONSESociety Formerly Nonlinearity in Biology, Toxicology, and Medicine www.Dose-Response.org Copyright © 2009 University of Massachusetts ISSN: 1559-3258 DOI: 10.2203/dose-response.08-024.Cuttler NUCLEAR ENERGY AND HEALTH And the Benefits of Low-Dose Radiation Hormesis Jerry M. Cuttler ᮀ Cuttler & Associates Inc., Mississauga, ON, Canada Myron Pollycove ᮀ School of Medicine, University of California San Francisco, San Francisco, CA ᮀ Energy needs worldwide are expected to increase for the foreseeable future, but fuel supplies are limited. Nuclear reactors could supply much of the energy demand in a safe, sustainable manner were it not for fear of potential releases of radioactivity.
    [Show full text]
  • Overview of Biological, Epidemiological, and Clinical Evidence of Radiation Hormesis
    Review Overview of Biological, Epidemiological, and Clinical Evidence of Radiation Hormesis Yuta Shibamoto 1,* and Hironobu Nakamura 2,3 1 Department of Radiology, Nagoya City University Graduate School of Medical Sciences, Nagoya 467-8601, Japan 2 Department of Radiology, Osaka University Graduate School of Medicine, Osaka 565-0871, Japan; [email protected] 3 Department of Radiology, Saito Yukokai Hospital, Osaka 567-0085, Japan * Correspondence: [email protected]; Tel.: +81-52-853-8274 Received: 2 July 2018; Accepted: 9 August 2018; Published: 13 August 2018 Abstract: The effects of low-dose radiation are being increasingly investigated in biological, epidemiological, and clinical studies. Many recent studies have indicated the beneficial effects of low doses of radiation, whereas some studies have suggested harmful effects even at low doses. This review article introduces various studies reporting both the beneficial and harmful effects of low-dose radiation, with a critique on the extent to which respective studies are reliable. Epidemiological studies are inherently associated with large biases, and it should be evaluated whether the observed differences are due to radiation or other confounding factors. On the other hand, well-controlled laboratory studies may be more appropriate to evaluate the effects of low-dose radiation. Since the number of such laboratory studies is steadily increasing, it will be concluded in the near future whether low-dose radiation is harmful or beneficial and whether the linear-no-threshold (LNT) theory is appropriate. Many recent biological studies have suggested the induction of biopositive responses such as increases in immunity and antioxidants by low-dose radiation.
    [Show full text]
  • Cuttler – Risk Vs Hormesis
    Proceedings of the 25th Annual Conference of the Canadian Nuclear Society, Toronto, June 6-9, 2004 What Becomes of Nuclear Risk Assessment in Light of Radiation Hormesis? Jerry M. Cuttler Cuttler & Associates Inc. [email protected] Abstract – A nuclear probabilistic risk or safety assessment (PRA or PSA) is a scientific calculation that uses assumptions and models to determine the likelihood of plant or fuel repository failures and the corresponding releases of radioactivity. Estimated radiation doses to the surrounding population are linked inappropriately to risks of cancer death and congenital malformations. Even though PRAs use very pessimistic assumptions, they demonstrate that nuclear power plants and fuel repositories are very safe compared with the health risks of other generating options or other risks that people readily accept. Because of the frightening negative images and the exaggerated safety and health concerns that are communicated, many people judge nuclear risks to be unacceptable and do not favour nuclear plants. Large-scale tests and experience with nuclear accidents demonstrate that even severe accidents expose the public to only low doses of radiation, and a century of research has demonstrated that such exposures are beneficial to health. A scientific basis for this phenomenon now exists. PRAs are valuable tools for improving plant designs, but if nuclear power is to play a significant role in meeting future energy needs, we must communicate its many real benefits and dispel the negative images formed by unscientific extrapolations of harmful effects at high doses. 1. NUCLEAR RISK ASSESSMENT Nuclear engineers calculate the likelihood of all possible accidents at a nuclear power plant and the resulting probability that people nearby might be harmed by such accidents.
    [Show full text]
  • It's Time for a New Low-Dose-Radiation Risk Assessment Paradigm—One That Acknowledges Hormesis
    View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by ScholarWorks@UMass Amherst Dose-Response: An International Journal Volume 6 | Issue 4 Article 4 12-2008 IT’S TIME FOR A NEW LOW-DOSE- RADIATION RISK ASSESSMENT PARADIGM—ONE THAT ACKNOWLEDGES HORMESIS Bobby R Scott Lovelace Respiratory Research Institute, Albuquerque, NM Follow this and additional works at: https://scholarworks.umass.edu/dose_response Recommended Citation Scott, Bobby R (2008) "IT’S TIME FOR A NEW LOW-DOSE-RADIATION RISK ASSESSMENT PARADIGM—ONE THAT ACKNOWLEDGES HORMESIS," Dose-Response: An International Journal: Vol. 6 : Iss. 4 , Article 4. Available at: https://scholarworks.umass.edu/dose_response/vol6/iss4/4 This Article is brought to you for free and open access by ScholarWorks@UMass Amherst. It has been accepted for inclusion in Dose-Response: An International Journal by an authorized editor of ScholarWorks@UMass Amherst. For more information, please contact [email protected]. Scott: New low-dose-radiation risk assessment paradigm Dose-Response, 6:333–351, 2008 InternationalDOSE-RESPONSESociety Formerly Nonlinearity in Biology, Toxicology, and Medicine www.Dose-Response.org Copyright © 2007 University of Massachusetts ISSN: 1559-3258 DOI: 10.2203/dose-response.07-005.Scott IT’S TIME FOR A NEW LOW-DOSE-RADIATION RISK ASSESSMENT PARADIGM—ONE THAT ACKNOWLEDGES HORMESIS Bobby R. Scott, PhD h Lovelace Respiratory Research Institute h The current system of radiation protection for humans is based on the linear-no- threshold (LNT) risk-assessment paradigm. Perceived harm to irradiated nuclear workers and the public is mainly reflected through calculated hypothetical increased cancers.
    [Show full text]
  • Low Dose and Low Dose-Rate Radiation Effects and Models
    Forty-Fourth Annual Meeting Program Low Dose and Low Dose-Rate Radiation Effects and Models April 14–15, 2008 Bethesda North Marriott Hotel & Conference Center 5701 Marinelli Road North Bethesda, MD 20852 On the cover: • top: Two nuclei have each been “hit” by three alpha particles from a microbeam and show activated γH2AX foci at the site of the traversal. • center: Chromosome painting technology makes it possible to identify each human chromosome and characterize the number, location and types of aberrations produced by ionizing radiation. • bottom: Measuring the frequency of micronuclei provides a rapid measure of cytogenetic damage, which increases as a function of radiation dose. Introduction Low Dose and Low Dose-Rate Radiation Effects and Models Forty-Fourth Annual Meeting of the National Council on Radiation Protection and Measurements (NCRP) Potential human health effects of low doses of ionizing models of the biological responses and human health radiation such as those experienced in occupational impacts of exposure to low doses of radiation. The and medical exposures are of great contemporary meeting will feature presentations by international interest. Considerable debate exists over the applica- experts on the topics of (1) molecular, cellular, tissue, bility of a linear-nonthreshold model for characterizing and laboratory animal studies on the effects of expo- the biological responses and health effects of expo- sure to low dose and low dose-rate radiation, (2) sure to low radiation doses, and alternative models results of epidemiological studies on human health have been proposed. A related subject of interest and effects of low radiation doses in occupational, medical debate is the effect of the rate of delivery of radiation and other exposure scenarios, (3) potential impacts of doses on the biological and health outcomes of expo- these findings on future regulatory guidance and pub- sure.
    [Show full text]
  • Modelling Exposure-Response Relationships for Ionizing and Non-Ionizing Radiation
    Modelling Exposure-response Relationships for Ionizing and Non-ionizing Radiation Daniel Krewski, PhD, MHA Professor and Director McLaughlin Centre for Population Heath Risk Assessment & Risk Sciences International American Association of Physicists in Medicine (AAPM) Denver, Colorado August 2, 2017 Outline • A New Framework for Risk Science • Key Characteristics of Human Carcinogens • Ionizing Radiation – Sources of exposure – Medical uses of radiation – Occupational and environmental radiation exposures – Radiation hormesis: what do the data Indicate? • Non-ionizing Radiation – Sources of exposure – Epidemiological studies of RF fields • Risk Communication, Risk Perception and Risk Decision Making McLaughlin Centre for Population Health Risk Assessment The Next Generation Risk Science McLaughlin Centre for Population Health Risk Assessment Next Generation Risk Assessment McLaughlin Centre for Population Health Risk Assessment Three Cornerstones • New paradigm for toxicity testing (TT21C), based on perturbation of toxicity pathways • Advanced risk assessment methodologies, including those addressed in Science and Decisions • Population health approach: multiple health determinants and multiple interventions McLaughlin Centre for Population Health Risk Assessment Key Characteristics of Human Carcinogens McLaughlin Centre for Population Health Risk Assessment What can we learn about human cancer based on 50 years of cancer research? McLaughlin Centre for Population Health Risk Assessment IARC Scientific Publication No. 165 • Twenty chapters
    [Show full text]
  • Radioresistance of Brain Tumors
    cancers Review Radioresistance of Brain Tumors Kevin Kelley 1, Jonathan Knisely 1, Marc Symons 2,* and Rosamaria Ruggieri 1,2,* 1 Radiation Medicine Department, Hofstra Northwell School of Medicine, Northwell Health, Manhasset, NY 11030, USA; [email protected] (K.K.); [email protected] (J.K.) 2 The Feinstein Institute for Molecular Medicine, Hofstra Northwell School of Medicine, Northwell Health, Manhasset, NY 11030, USA * Correspondence: [email protected] (M.S.); [email protected] (R.R.); Tel.: +1-516-562-1193 (M.S.); +1-516-562-3410 (R.R.) Academic Editor: Zhe-Sheng (Jason) Chen Received: 17 January 2016; Accepted: 24 March 2016; Published: 30 March 2016 Abstract: Radiation therapy (RT) is frequently used as part of the standard of care treatment of the majority of brain tumors. The efficacy of RT is limited by radioresistance and by normal tissue radiation tolerance. This is highlighted in pediatric brain tumors where the use of radiation is limited by the excessive toxicity to the developing brain. For these reasons, radiosensitization of tumor cells would be beneficial. In this review, we focus on radioresistance mechanisms intrinsic to tumor cells. We also evaluate existing approaches to induce radiosensitization and explore future avenues of investigation. Keywords: radiation therapy; radioresistance; brain tumors 1. Introduction 1.1. Radiotherapy and Radioresistance of Brain Tumors Radiation therapy is a mainstay in the treatment of the majority of primary tumors of the central nervous system (CNS). However, the efficacy of this therapeutic approach is significantly limited by resistance to tumor cell killing after exposure to ionizing radiation. This phenomenon, termed radioresistance, can be mediated by factors intrinsic to the cell or by the microenvironment.
    [Show full text]
  • Radiation Hormesis
    JAERI-Conf 2005-001 JP0550169 33 Evidence for beneficial low level radiation effects and radiation hormesis L.E. Feinendegen Heinrich-Heine-University Dtisseldorf, Germany; Brookhaven National Laboratory, Upton, NY, USA Abstract Low doses in the mGy range cause a dual effect on cellular DNA. One effect concerns a relatively low probability of DNA damage per energy deposition event and it increases proportional with dose, with possible bystander effects operating. This damage at background radiation exposure is orders of magnitudes lower than that from endogenous sources, such as ROS. The other effect at comparable doses brings an easily observable adaptive protection against DNA damage from any, mainly endogenous sources, depending on cell type, species, and metabolism. Protective responses express adaptive responses to metabolic perturbations and also mimic oxygen stress responses. Adaptive protection operates in terms of DNA damage prevention and repair, and of immune stimulation. It develops with a delay of hours, may last for days to months, and increasingly disappears at doses beyond about 100 to 200 mGy. Radiation-induced apoptosis and terminal cell differentiation occurs also at higher doses and adds to protection by reducing genomic instability and the number of mutated cells in tissues. At low doses, damage reduction by adaptive protection against damage from endogenous sources predictably outweighs radiogenic damage induction. The analysis of the consequences of the particular low-dose scenario shows that the linear-no-threshold (LNT) hypothesis for cancer risk is scientifically unfounded and appears to be invalid in favor of a threshold or hormesis. This is consistent with data both from animal studies and human epidemiological observations on low-dose induced cancer.
    [Show full text]
  • The Power of Stress: the Telo-Hormesis Hypothesis
    cells Review The Power of Stress: The Telo-Hormesis Hypothesis Maria Sol Jacome Burbano 1 and Eric Gilson 1,2,* 1 Institut for Research on Cancer and Aging, Université Côte d’Azur, CNRS, Inserm, Nice (IRCAN), 06107 Nice, France; [email protected] 2 Department of Medical Genetics, Archet 2 Hospital, FHU Oncoage, CHU of Nice, 06107 Nice, France * Correspondence: [email protected] Abstract: Adaptative response to stress is a strategy conserved across evolution to promote survival. In this context, the groundbreaking findings of Miroslav Radman on the adaptative value of changing mutation rates opened new avenues in our understanding of stress response. Inspired by this work, we explore here the putative beneficial effects of changing the ends of eukaryotic chromosomes, the telomeres, in response to stress. We first summarize basic principles in telomere biology and then describe how various types of stress can alter telomere structure and functions. Finally, we discuss the hypothesis of stress-induced telomere signaling with hormetic effects. Keywords: telomeres; hormesis; stress response; adaptation 1. Introduction To survive and reproduce, living organisms must maintain homeostasis both in un- challenged (normal) and challenged (stressful) contexts. This requires the evolution of powerful stress response mechanisms adapted to a particular ecosystem and to regular Citation: Jacome Burbano, M.S.; environmental fluctuations. Thus, these mechanisms may be very diverse within the Gilson, E. The Power of Stress: The tree of life. The pioneering work of Miroslav Radman on the stress response in bacteria Telo-Hormesis Hypothesis. Cells 2021, demonstrated the rapid and adaptive value of changing mutation rates for rapid evolution 10, 1156.
    [Show full text]
  • Human Radiosensitivity and Radiosusceptibility: What Are the Differences?
    International Journal of Molecular Sciences Review Human Radiosensitivity and Radiosusceptibility: What Are the Differences? Laura El-Nachef 1, Joelle Al-Choboq 1, Juliette Restier-Verlet 1, Adeline Granzotto 1, Elise Berthel 1,2, Laurène Sonzogni 1,Mélanie L. Ferlazzo 1, Audrey Bouchet 1 , Pierre Leblond 3, Patrick Combemale 3, Stéphane Pinson 4, Michel Bourguignon 1,5 and Nicolas Foray 1,* 1 Inserm, U1296 unit, Radiation: Defense, Health and Environment, Centre Léon-Bérard, 28, rue Laennec, 69008 Lyon, France; [email protected] (L.E.-N.); [email protected] (J.A.-C.); Juliette.Restier–[email protected] (J.R.-V.); [email protected] (A.G.); [email protected] (E.B.); [email protected] (L.S.); [email protected] (M.L.F.); [email protected] (A.B.); [email protected] (M.B.) 2 Neolys Diagnostics, 67960 Entzheim, France 3 Centre Léon-Bérard, 28, rue Laennec, 69008 Lyon, France; [email protected] (P.L.); [email protected] (P.C.) 4 Hospices Civils de Lyon, Quai des Célestins, 69002 Lyon, France; [email protected] 5 Université Paris Saclay Versailles St Quentin en Yvelines, 78035 Versailles, France * Correspondence: [email protected]; Tel.: +33-4-78-78-28-28 Abstract: The individual response to ionizing radiation (IR) raises a number of medical, scientific, and societal issues. While the term “radiosensitivity” was used by the pioneers at the beginning Citation: El-Nachef, L.; Al-Choboq, of the 20st century to describe only the radiation-induced adverse tissue reactions related to cell J.; Restier-Verlet, J.; Granzotto, A.; death, a confusion emerged in the literature from the 1930s, as “radiosensitivity” was indifferently Berthel, E.; Sonzogni, L.; Ferlazzo, used to describe the toxic, cancerous, or aging effect of IR.
    [Show full text]