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PURPOSE: Childhood cancer survivors, in particular those treated with radiation therapy, are at high risk of long-term iatrogenic events. The prediction of risk of such events is mainly based on the knowledge of the radiation dose received to healthy organs and tissues during treatment of childhood cancer diagnosed decades ago. We aimed to set up a standardized organ dose table to help former patients and clinicians in charge of long-term follow-up clinics. METHODS AND MATERIALS: We performed whole body dosimetric reconstruction for 2646 patients from 12 European countries treated between 1941 and 2006 (median, 1976). Most plannings were 2- or 3-dimensional. A total of 46% of patients were treated using Cobalt 60, and 41%, using a linear accelerator. The median prescribed dose was 27.2 Gy (IQ1-IQ3, 17.6-40.0 Gy). A patient-specific voxel-based anthropomorphic phantom with more than 200 anatomic structures or substructures delineated as a surrogate of each subject's anatomy was used. The radiation therapy was simulated with a treatment planning system based on available treatment information. The radiation dose received by any organ of the body was estimated by extending the treatment planning system dose calculation to the whole body, by type and localization of childhood cancer. RESULTS: The integral dose and normal tissue doses to most of the 23 considered organs increased between the 1950s and 1970s and decreased or plateaued thereafter. Whatever the organ considered, the type of childhood cancer explained most of the variability in organ dose. The country of treatment explained only a small part of the variability. CONCLUSIONS: The detailed dose estimates provide very useful information for former patients or clinicians who have only limited knowledge about radiation therapy protocols or techniques, but who know the type and site of childhood cancer, sex, age, and year of treatment. This will allow better prediction of the long-term risk of iatrogenic events and better referral to long-term follow-up clinics.
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Recent epidemiologic studies support an association between chronic low-dose radiation exposure and the development of cardiovascular disease (CVD). The molecular mechanisms underlying the adverse effect of chronic low dose exposure are not fully understood. To address this issue, we have investigated changes in the heart proteome of ApoE deficient (ApoE-/-) C57Bl/6 female mice chronically irradiated for 300 days at a very low dose rate (1 mGy/day) or at a low dose rate (20 mGy/day), resulting in cumulative whole-body doses of 0.3 Gy or 6.0 Gy, respectively. The heart proteomes were compared to those of age-matched sham-irradiated ApoE-/- mice using label-free quantitative proteomics. Radiation-induced proteome changes were further validated using immunoblotting, enzyme activity assays, immunohistochemistry or targeted transcriptomics. The analyses showed persistent alterations in the cardiac proteome at both dose rates; however, the effect was more pronounced following higher dose rates. The altered proteins were involved in cardiac energy metabolism, ECM remodelling, oxidative stress, and ageing signalling pathways. The changes in PPARα, SIRT, AMPK, and mTOR signalling pathways were found at both dose rates and in a dose-dependent manner, whereas more changes in glycolysis and ECM remodelling were detected at the lower dose rate. These data provide strong evidence for the possible risk of cardiac injury following chronic low dose irradiation and show that several affected pathways following chronic irradiation overlap with those of ageing-associated heart pathology.
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Extracellular vesicles (EVs), through their cargo, are important mediators of bystander responses in the irradiated bone marrow (BM). MiRNAs carried by EVs can potentially alter cellular pathways in EV-recipient cells by regulating their protein content. Using the CBA/Ca mouse model, we characterised the miRNA content of BM-derived EVs from mice irradiated with 0.1 Gy or 3 Gy using an nCounter analysis system. We also analysed proteomic changes in BM cells either directly irradiated or treated with EVs derived from the BM of irradiated mice. Our aim was to identify key cellular processes in the EV-acceptor cells regulated by miRNAs. The irradiation of BM cells with 0.1 Gy led to protein alterations involved in oxidative stress and immune and inflammatory processes. Oxidative stress-related pathways were also present in BM cells treated with EVs isolated from 0.1 Gy-irradiated mice, indicating the propagation of oxidative stress in a bystander manner. The irradiation of BM cells with 3 Gy led to protein pathway alterations involved in the DNA damage response, metabolism, cell death and immune and inflammatory processes. The majority of these pathways were also altered in BM cells treated with EVs from mice irradiated with 3 Gy. Certain pathways (cell cycle, acute and chronic myeloid leukaemia) regulated by miRNAs differentially expressed in EVs isolated from mice irradiated with 3 Gy overlapped with protein pathway alterations in BM cells treated with 3 Gy EVs. Six miRNAs were involved in these common pathways interacting with 11 proteins, suggesting the involvement of miRNAs in the EV-mediated bystander processes. In conclusion, we characterised proteomic changes in directly irradiated and EV-treated BM cells, identified processes transmitted in a bystander manner and suggested miRNA and protein candidates potentially involved in the regulation of these bystander processes.
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Vesículas Extracelulares , MicroRNAs , Camundongos , Animais , MicroRNAs/genética , MicroRNAs/metabolismo , Medula Óssea/metabolismo , Proteômica , Camundongos Endogâmicos CBA , Vesículas Extracelulares/metabolismo , Radiação IonizanteRESUMO
OBJECTIVE: To systematically review and perform a meta-analysis of radiation associated risks of cardiovascular disease in all groups exposed to radiation with individual radiation dose estimates. DESIGN: Systematic review and meta-analysis. MAIN OUTCOME MEASURES: Excess relative risk per unit dose (Gy), estimated by restricted maximum likelihood methods. DATA SOURCES: PubMed and Medline, Embase, Scopus, Web of Science Core collection databases. ELIGIBILITY CRITERIA FOR SELECTING STUDIES: Databases were searched on 6 October 2022, with no limits on date of publication or language. Animal studies and studies without an abstract were excluded. RESULTS: The meta-analysis yielded 93 relevant studies. Relative risk per Gy increased for all cardiovascular disease (excess relative risk per Gy of 0.11 (95% confidence interval 0.08 to 0.14)) and for the four major subtypes of cardiovascular disease (ischaemic heart disease, other heart disease, cerebrovascular disease, all other cardiovascular disease). However, interstudy heterogeneity was noted (P<0.05 for all endpoints except for other heart disease), possibly resulting from interstudy variation in unmeasured confounders or effect modifiers, which is markedly reduced if attention is restricted to higher quality studies or those at moderate doses (<0.5 Gy) or low dose rates (<5 mGy/h). For ischaemic heart disease and all cardiovascular disease, risks were larger per unit dose for lower dose (inverse dose effect) and for fractionated exposures (inverse dose fractionation effect). Population based excess absolute risks are estimated for a number of national populations (Canada, England and Wales, France, Germany, Japan, USA) and range from 2.33% per Gy (95% confidence interval 1.69% to 2.98%) for England and Wales to 3.66% per Gy (2.65% to 4.68%) for Germany, largely reflecting the underlying rates of cardiovascular disease mortality in these populations. Estimated risk of mortality from cardiovascular disease are generally dominated by cerebrovascular disease (around 0.94-1.26% per Gy), with the next largest contribution from ischaemic heart disease (around 0.30-1.20% per Gy). CONCLUSIONS: Results provide evidence supporting a causal association between radiation exposure and cardiovascular disease at high dose, and to a lesser extent at low dose, with some indications of differences in risk between acute and chronic exposures, which require further investigation. The observed heterogeneity complicates a causal interpretation of these findings, although this heterogeneity is much reduced if only higher quality studies or those at moderate doses or low dose rates are considered. Studies are needed to assess in more detail modifications of radiation effect by lifestyle and medical risk factors. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42020202036.
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Doenças Cardiovasculares , Doença da Artéria Coronariana , Isquemia Miocárdica , Humanos , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Isquemia Miocárdica/epidemiologia , Isquemia Miocárdica/etiologia , Fatores de Risco , França , Radiação Ionizante , Doença da Artéria Coronariana/complicaçõesRESUMO
Recent reports have shown a link between radiation exposure and non-cancer diseases such as radiation-induced heart disease (RIHD). Radiation exposures are often inhomogeneous, and out-of-target effects have been studied in terms of cancer risk, but very few studies have been carried out for non-cancer diseases. Here, the role of miRNAs in the pathogenesis of RIHD was investigated. C57Bl/6J female mice were whole- (WBI) or partial-body-irradiated (PBI) with 2 Gy of X-rays or sham-irradiated (SI). In PBI exposure, the lower third of the mouse body was irradiated, while the upper two-thirds were shielded. From all groups, hearts were collected 15 days or 6 months post-irradiation. The MiRNome analysis at 15 days post-irradiation showed that miRNAs, belonging to the myomiR family, were highly differentially expressed in WBI and PBI mouse hearts compared with SI hearts. Raman spectral data collected 15 days and 6 months post-irradiation showed biochemical differences among SI, WBI and PBI mouse hearts. Fibrosis in WBI and PBI mouse hearts, indicated by the increased deposition of collagen and the overexpression of genes involved in myofibroblast activation, was found 6 months post-irradiation. Using an in vitro co-culture system, involving directly irradiated skeletal muscle and unirradiated ventricular cardiac human cells, we propose the role of miR-1/133a as mediators of the abscopal response, suggesting that miRNA-based strategies could be relevant for limiting tissue-dependent reactions in non-directly irradiated tissues.
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PURPOSE: The aim of this study was to explore the effects of chronic low-dose-rate gamma-radiation at a multi-scale level. The specific objective was to obtain an overall view of the endothelial cell response, by integrating previously published data on different cellular endpoints and highlighting possible different mechanisms underpinning radiation-induced senescence. MATERIALS AND METHODS: Different datasets were collected regarding experiments on human umbilical vein endothelial cells (HUVECs) which were chronically exposed to low dose rates (0, 1.4, 2.1 and 4.1 mGy/h) of gamma-rays until cell replication was arrested. Such exposed cells were analyzed for different complementary endpoints at distinct time points (up to several weeks), investigating cellular functions such as proliferation, senescence and angiogenic properties, as well as using transcriptomics and proteomics profiling. A mathematical model was proposed to describe proliferation and senescence. RESULTS: Simultaneous ceasing of cell proliferation and senescence onset as a function of time were well reproduced by the logistic growth curve, conveying shared equilibria between the two endpoints. The combination of all the different endpoints investigated highlighted a dose-dependence for prematurely induced senescence. However, the underpinning molecular mechanisms appeared to be dissimilar for the different dose rates, thus suggesting a more complex scenario. CONCLUSIONS: This study was conducted integrating different datasets, focusing on their temporal dynamics, and using a systems biology approach. Results of our analysis highlight that different dose rates have different effects in inducing premature senescence, and that the total cumulative absorbed dose also plays an important role in accelerating endothelial cell senescence.
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Senescência Celular , Biologia de Sistemas , Células Cultivadas , Raios gama/efeitos adversos , Células Endoteliais da Veia Umbilical Humana , Humanos , RadiobiologiaRESUMO
Cell communication via exosomes is capable of influencing cell fate in stress situations such as exposure to ionizing radiation. In vitro and in vivo studies have shown that exosomes might play a role in out-of-target radiation effects by carrying molecular signaling mediators of radiation damage, as well as opposite protective functions resulting in resistance to radiotherapy. However, a global understanding of exosomes and their radiation-induced regulation, especially within the context of an intact mammalian organism, has been lacking. In this in vivo study, we demonstrate that, compared to sham-irradiated (SI) mice, a distinct pattern of proteins and miRNAs is found packaged into circulating plasma exosomes after whole-body and partial-body irradiation (WBI and PBI) with 2 Gy X-rays. A high number of deregulated proteins (59% of WBI and 67% of PBI) was found in the exosomes of irradiated mice. In total, 57 and 13 miRNAs were deregulated in WBI and PBI groups, respectively, suggesting that the miRNA cargo is influenced by the tissue volume exposed to radiation. In addition, five miRNAs (miR-99b-3p, miR-200a-3p, miR-200a, miR-182-5p, miR-182) were commonly overexpressed in the exosomes from the WBI and PBI groups. In this study, particular emphasis was also given to the determination of the in vivo effect of exosome transfer by intracranial injection in the highly radiosensitive neonatal cerebellum at postnatal day 3. In accordance with a major overall anti-apoptotic function of the commonly deregulated miRNAs, here, we report that exosomes from the plasma of irradiated mice, especially in the case of WBI, prevent radiation-induced apoptosis, thus holding promise for exosome-based future therapeutic applications against radiation injury.
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Exossomos , MicroRNAs , Lesões por Radiação , Animais , Apoptose , Cerebelo/metabolismo , Exossomos/metabolismo , Mamíferos/metabolismo , Camundongos , MicroRNAs/genética , MicroRNAs/metabolismo , Proteômica , Lesões por Radiação/metabolismoRESUMO
PURPOSE: The aim of this article is to describe the technical development in proteomics during the last two decades with the focus on its use in radiation biology. It is written from a subjective point of view and aims not to be a scientific review of the subject. CONCLUSION: Proteomics is a fast developing technique and it has already contributed greatly to our understanding of biological mechanisms following radiation exposure. Novel proteomics approaches can be used in adequately designed cellular and animal experiments and above all in big clinical trials to investigate effects of ionizing radiation in the future.
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Proteômica , Radiação Ionizante , Animais , Proteômica/métodos , RadiobiologiaRESUMO
Background and Purpose: Cardiotoxicity is a well-known adverse effect of radiation therapy. Measurable abnormalities in the heart function indicate advanced and often irreversible heart damage. Therefore, early detection of cardiac toxicity is necessary to delay and alleviate the development of the disease. The present study investigated long-term serum proteome alterations following local heart irradiation using a mouse model with the aim to detect biomarkers of radiation-induced cardiac toxicity. Materials and Methods: Serum samples from C57BL/6J mice were collected 20 weeks after local heart irradiation with 8 or 16 Gy X-ray; the controls were sham-irradiated. The samples were analyzed by quantitative proteomics based on data-independent acquisition mass spectrometry. The proteomics data were further investigated using bioinformatics and ELISA. Results: The analysis showed radiation-induced changes in the level of several serum proteins involved in the acute phase response, inflammation, and cholesterol metabolism. We found significantly enhanced expression of proinflammatory cytokines (TNF-α, TGF-ß, IL-1, and IL-6) in the serum of the irradiated mice. The level of free fatty acids, total cholesterol, low-density lipoprotein (LDL), and oxidized LDL was increased, whereas that of high-density lipoprotein was decreased by irradiation. Conclusions: This study provides information on systemic effects of heart irradiation. It elucidates a radiation fingerprint in the serum that may be used to elucidate adverse cardiac effects after radiation therapy.
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Coração , Proteômica , Animais , Biomarcadores/sangue , Coração/efeitos da radiação , Camundongos , Camundongos Endogâmicos C57BL , ProteomaRESUMO
The brain undergoes ionizing radiation exposure in many clinical situations, particularly during radiotherapy for brain tumors. The critical role of the hippocampus in the pathogenesis of radiation-induced neurocognitive dysfunction is well recognized. The goal of this study is to test the potential contribution of non-targeted effects in the detrimental response of the hippocampus to irradiation and to elucidate the mechanisms involved. C57Bl/6 mice were whole body (WBI) or partial body (PBI) irradiated with 0.1 or 2.0 Gy of X-rays or sham irradiated. PBI consisted of the exposure of the lower third of the mouse body, whilst the upper two thirds were shielded. Hippocampi were collected 15 days or 6 months post-irradiation and a multi-omics approach was adopted to assess the molecular changes in non-coding RNAs, proteins and metabolic levels, as well as histological changes in the rate of hippocampal neurogenesis. Notably, at 2.0 Gy the pattern of early molecular and histopathological changes induced in the hippocampus at 15 days following PBI were similar in quality and quantity to the effects induced by WBI, thus providing a proof of principle of the existence of out-of-target radiation response in the hippocampus of conventional mice. We detected major alterations in DAG/IP3 and TGF-ß signaling pathways as well as in the expression of proteins involved in the regulation of long-term neuronal synaptic plasticity and synapse organization, coupled with defects in neural stem cells self-renewal in the hippocampal dentate gyrus. However, compared to the persistence of the WBI effects, most of the PBI effects were only transient and tended to decrease at 6 months post-irradiation, indicating important mechanistic difference. On the contrary, at low dose we identified a progressive accumulation of molecular defects that tended to manifest at later post-irradiation times. These data, indicating that both targeted and non-targeted radiation effects might contribute to the pathogenesis of hippocampal radiation-damage, have general implications for human health.
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Irradiação Craniana , Hipocampo/metabolismo , Hipocampo/efeitos da radiação , Metaboloma , Neurogênese/genética , Neurogênese/efeitos da radiação , Proteoma , Transcriptoma , Animais , Biologia Computacional/métodos , Irradiação Craniana/efeitos adversos , Feminino , Regulação da Expressão Gênica , Imuno-Histoquímica , Camundongos , Doses de Radiação , Transdução de SinaisRESUMO
PURPOSE: The long-term effect of low and moderate doses of ionizing radiation on the lens is still a matter of debate and needs to be evaluated in more detail. MATERIAL AND METHODS: We conducted a detailed histological analysis of eyes from B6C3F1 mice cohorts after acute gamma irradiation (60Co source; 0.063 Gy/min) at young adult age of 10 weeks with doses of 0.063, 0.125, and 0.5 Gy. Sham irradiated (0 Gy) mice were used as controls. To test for genetic susceptibility heterozygous Ercc2 mutant mice were used and compared to wild-type mice of the same strain background. Mice of both sexes were included in all cohorts. Eyes were collected 4 h, 12, 18 and 24 months after irradiation. For a better understanding of the underlying mechanisms, metabolomics analyses were performed in lenses and plasma samples of the same mouse cohorts at 4 and 12 h as well as 12, 18 and 24 months after irradiation. For this purpose, a targeted analysis was chosen. RESULTS: This analysis revealed histological changes particularly in the posterior part of the lens that rarely can be observed by using Scheimpflug imaging, as we reported previously. We detected a significant increase of posterior subcapsular cataracts (PSCs) 18 and 24 months after irradiation with 0.5 Gy (odds ratio 9.3; 95% confidence interval 2.1-41.3) independent of sex and genotype. Doses below 0.5 Gy (i.e. 0.063 and 0.125 Gy) did not significantly increase the frequency of PSCs at any time point. In lenses, we observed a clear effect of sex and aging but not of irradiation or genotype. While metabolomics analyses of plasma from the same mice showed only a sex effect. CONCLUSIONS: This article demonstrates a significant radiation-induced increase in the incidence of PSCs, which could not be identified using Scheimpflug imaging as the only diagnostic tool.
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Catarata/etiologia , Lesões por Radiação/etiologia , Animais , Catarata/genética , Relação Dose-Resposta à Radiação , Feminino , Heterozigoto , Cristalino/efeitos da radiação , Masculino , Camundongos , Lesões por Radiação/genéticaRESUMO
Extracellular vesicles (EVs) are freely circulating nano/micrometer-sized membrane-bound vesicles released by various cell types. Their cargo consists of proteins, lipids, metabolites, and different types of RNA molecules reflecting the origin of the secreting cell type or tissue. Since the EV cargo is constantly changing in response to pathological status or different environmental stressors, it has been extensively studied in the quest for biomarkers, especially in the cancer research. Mass spectrometry (MS)-based proteome analysis is a powerful tool to elucidate the protein cargo in EVs. This chapter describes and characterizes three MS-compatible lysis methods, namely by using urea, guanidium hydrochloride, and radioimmunoprecipitation buffer for isolating proteins from EVs.
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Métodos Analíticos de Preparação de Amostras , Exossomos/metabolismo , Espectrometria de Massas , Proteínas/isolamento & purificação , Proteômica , Animais , Células Cultivadas , Guanidina/química , Humanos , Imunoprecipitação , Ureia/químicaRESUMO
Risks to health are the prime consideration in all human situations of ionizing radiation exposure and therefore of relevance to radiation protection in all occupational, medical, and public exposure situations. Over the past few decades, advances in therapeutic strategies have led to significant improvements in cancer survival rates. However, a wide range of long-term complications have been reported in cancer survivors, in particular circulatory diseases and their major risk factors, metabolic diseases. However, at lower levels of exposure, the evidence is less clear. Under real-life exposure scenarios, including radiotherapy, radiation effects in the whole organism will be determined mainly by the response of normal tissues receiving relatively low doses, and will be mediated and moderated by systemic effects. Therefore, there is an urgent need for further research on the impact of low-dose radiation. In this article, we review radiation-associated risks of circulatory and metabolic diseases in clinical, occupational or environmental exposure situations, addressing epidemiological, biological, risk modelling, and systems biology aspects, highlight the gaps in knowledge and discuss future directions to address these gaps.
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Doenças Cardiovasculares , Doenças Metabólicas , Exposição Ocupacional , Lesões por Radiação , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Exposição Ambiental , Humanos , Doenças Metabólicas/etiologia , Lesões por Radiação/epidemiologia , Lesões por Radiação/etiologia , Radiação IonizanteRESUMO
PURPOSE: The MSc Radiation Biology course is a highly interdisciplinary degree program placing radiation biology at the interface between biology, medicine, and physics, as well as their associated technologies. The goal was to establish an internationally acknowledged program with diverse and heterogeneous student cohorts, who benefit from each other academically as well as culturally. We have completed a Five-Year evaluation of the program to assess our qualification profile and the further direction we want to take. MATERIALS AND METHODS: We evaluated the student cohort's data from the last 5 years regarding gender, age, and nationality as well as the highest degree before applying and career path after graduation. RESULTS: Data shows a great diversity regarding nationalty as well as undergraduate background. Cohort sizes could be increased and future prospects mainly aimed to a PhD. Measures after regular quality meetings and students' feedback led to improving the curriculum and workload, teacher's training, and changes to examination regulations. CONCLUSIONS: After 5 years, statistics show that our expectations have been met exceedingly. All graduates had excellent career opportunities reflecting the necessity of this MSc and its topics. We are continuously working on improving the program and adapting the curriculum to the requirements in radiation sciences. The future vision includes an expansion of the program as well as undergraduate education opportunities in this field.
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Radiobiologia/educação , Adulto , Currículo , Feminino , Humanos , MasculinoRESUMO
Molecular communication between irradiated and unirradiated neighbouring cells initiates radiation-induced bystander effects (RIBE) and out-of-field (abscopal) effects which are both an example of the non-targeted effects (NTE) of ionising radiation (IR). Exosomes are small membrane vesicles of endosomal origin and newly identified mediators of NTE. Although exosome-mediated changes are well documented in radiation therapy and oncology, there is a lack of knowledge regarding the role of exosomes derived from inside and outside the radiation field in the early and delayed induction of NTE following IR. Therefore, here we investigated the changes in exosome profile and the role of exosomes as possible molecular signalling mediators of radiation damage. Exosomes derived from organs of whole body irradiated (WBI) or partial body irradiated (PBI) mice after 24 h and 15 days post-irradiation were transferred to recipient mouse embryonic fibroblast (MEF) cells and changes in cellular viability, DNA damage and calcium, reactive oxygen species and nitric oxide signalling were evaluated compared to that of MEF cells treated with exosomes derived from unirradiated mice. Taken together, our results show that whole and partial-body irradiation increases the number of exosomes, instigating changes in exosome-treated MEF cells, depending on the source organ and time after exposure.
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Exossomos/efeitos da radiação , Lesões por Radiação/patologia , Animais , Efeito Espectador/efeitos da radiação , Cálcio/metabolismo , Sobrevivência Celular/efeitos da radiação , Células Cultivadas , Dano ao DNA/efeitos da radiação , Exossomos/metabolismo , Feminino , Fibroblastos/metabolismo , Fibroblastos/efeitos da radiação , Camundongos , Camundongos Endogâmicos C57BL , Óxido Nítrico/metabolismo , Lesões por Radiação/metabolismo , Radiação Ionizante , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos da radiaçãoRESUMO
Radiation-induced inflammation leading to the permeability of the endothelial barrier may increase the risk of cardiovascular disease. The aim of this study was to investigate potential mechanisms in vitro at the level of the proteome in human coronary artery endothelial cells (HCECest2) that were exposed to radiation doses of 0, 0.25, 0.5, 2.0 and 10 Gy (60Co-γ). Proteomics analysis was performed using mass spectrometry in a label-free data-independent acquisition mode. The data were validated using bioinformatics and immunoblotting. The low- and moderate-dose-irradiated samples (0.25 Gy, 0.5 Gy) showed only scarce proteome changes. In contrast, an activation of DNA-damage repair, inflammation, and oxidative stress pathways was seen after the high-dose treatments (2 and 10 Gy). The level of the DNA damage response protein DDB2 was enhanced early at the 10 Gy dose. The expression of proteins belonging to the inflammatory response or cGAS-STING pathway (STING, STAT1, ICAM1, ISG15) increased in a dose-dependent manner, showing the strongest effects at 10 Gy after one week. This study suggests a connection between the radiation-induced DNA damage and the induction of inflammation which supports the inhibition of the cGAS-STING pathway in the prevention of radiation-induced cardiovascular disease.
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Epidemiological studies on workers employed at the Mayak plutonium enrichment plant have demonstrated an association between external gamma ray exposure and an elevated risk of ischemic heart disease (IHD). In a previous study using fresh-frozen post mortem samples of the cardiac left ventricle of Mayak workers and non-irradiated controls, we observed radiation-induced alterations in the heart proteome, mainly downregulation of mitochondrial and structural proteins. As the control group available at that time was younger than the irradiated group, we could not exclude age as a confounding factor. To address this issue, we have now expanded our study to investigate additional samples using archival formalin-fixed paraffin-embedded (FFPE) tissue. Importantly, the control group studied here is older than the occupationally exposed (>500 mGy) group. Label-free quantitative proteomics analysis showed that proteins involved in the lipid metabolism, sirtuin signaling, mitochondrial function, cytoskeletal organization, and antioxidant defense were the most affected. A histopathological analysis elucidated large foci of fibrotic tissue, myocardial lipomatosis and lymphocytic infiltrations in the irradiated samples. These data highlight the suitability of FFPE material for proteomics analysis. The study confirms the previous results emphasizing the role of adverse metabolic changes in the radiation-associated IHD. Most importantly, it excludes age at the time of death as a confounding factor.
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Isquemia Miocárdica/metabolismo , Plutônio/efeitos adversos , Proteoma/metabolismo , Proteoma/efeitos da radiação , Cromatografia Líquida , Citoesqueleto/metabolismo , Citoesqueleto/efeitos da radiação , Formaldeído/química , Humanos , Metabolismo dos Lipídeos/efeitos da radiação , Masculino , Mitocôndrias/metabolismo , Mitocôndrias/efeitos da radiação , Isquemia Miocárdica/epidemiologia , Isquemia Miocárdica/etiologia , Isquemia Miocárdica/patologia , Exposição Ocupacional , Inclusão em Parafina , Análise de Componente Principal , Mapas de Interação de Proteínas , Proteômica/métodos , Radiação Ionizante , Transdução de Sinais/efeitos da radiação , Sirtuínas/metabolismo , Espectrometria de Massas em Tandem , Fixação de TecidosRESUMO
In the current dismal situation of the COVID-19 pandemic, effective management of patients with pneumonia and acute respiratory distress syndrome is of vital importance. Due to the current lack of effective pharmacological concepts, this situation has caused interest in (re)considering historical reports on the treatment of patients with low-dose radiation therapy for pneumonia. Although these historical reports are of low-level evidence per se, hampering recommendations for decision-making in the clinical setting, they indicate effectiveness in the dose range between 0.3 and 1â¯Gy, similar to more recent dose concepts in the treatment of acute and chronic inflammatory/degenerative benign diseases with, e.g., a single dose per fraction of 0.5â¯Gy. This concise review aims to critically review the evidence for low-dose radiation treatment of COVID-19 pneumopathy and discuss whether it is worth investigating in the present clinical situation.
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Infecções por Coronavirus/radioterapia , Pneumonia Viral/radioterapia , Síndrome Respiratória Aguda Grave/radioterapia , COVID-19 , Medicina Baseada em Evidências , Humanos , Pandemias , Dosagem Radioterapêutica , Resultado do TratamentoRESUMO
Normal tissue toxicity is a dose-limiting factor in radiation therapy. Therefore, a detailed understanding of the normal tissue response to radiation is necessary to predict the risk of normal tissue toxicity and to development strategies for tissue protection. One component of normal tissue that is continuously exposed during therapeutic irradiation is the circulating population of peripheral blood mononuclear cells (PBMC). PBMCs are highly sensitive to ionizing radiation (IR); however, little is known about how IR affects the PBMC response on a systemic level. It was the aim of this study to investigate whether IR was capable to induce changes in the composition and function of extracellular vesicles (EVs) secreted from PBMCs after radiation exposure to different doses. Therefore, whole blood samples from healthy donors were exposed to X-ray radiation in the clinically relevant doses of 0, 0.1, 2 or 6 Gy and PBMC-secreted EVs were isolated 72 h later. Proteome and miRNome analysis of EVs as well as functional studies were performed. Secreted EVs showed a dose-dependent increase in the number of significantly deregulated proteins and microRNAs. For both, proteome and microRNA data, principal component analysis showed a dose-dependent separation of control and exposed groups. Integrated pathway analysis of the radiation-regulated EV proteins and microRNAs consistently predicted an association of deregulated molecules with apoptosis, cell death and survival. Functional studies identified endothelial cells as an efficient EV recipient system, in which irradiation of recipient cells further increased the uptake. Furthermore an apoptosis suppressive effect of EVs from irradiated PBMCs in endothelial recipient cells was detected. In summary, this study demonstrates that IR modifies the communication between PBMCs and endothelial cells. EVs from irradiated PBMC donors were identified as transmitters of protective signals to irradiated endothelial cells. Thus, these data may lead to the discovery of biomarker candidates for radiation dosimetry and even more importantly, they suggest EVs as a novel systemic communication pathway between irradiated normal, non-cancer tissues.
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Vesículas Extracelulares/metabolismo , Leucócitos Mononucleares/metabolismo , Leucócitos Mononucleares/efeitos da radiação , Exposição à Radiação , Vesículas Secretórias/metabolismo , Apoptose/efeitos da radiação , Células Endoteliais/metabolismo , Células Endoteliais/efeitos da radiação , Humanos , MicroRNAs/genética , Proteoma/metabolismo , Radiação Ionizante , Radioterapia/métodosRESUMO
Purpose: Pulmonary inflammation is an adverse consequence of radiation therapy in breast cancer. The aim of this study was to elucidate biological pathways leading to this pathology.Materials and methods: Lung endothelial cells were isolated 24 h after thorax-irradiation (sham or 10 Gy X-ray) from female C57Bl/6 mice and cultivated for 6 days.Results: Quantitative proteomic analysis of lung endothelial cells was done using data independent acquisition (DIA) mass spectrometry. The data were analyzed using Ingenuity Pathway Analysis and STRINGdb. In total, 4220 proteins were identified using DIA of which 60 were dysregulated in the irradiated samples (fold change ≥2.00 or ≤0.50; q-value <0.05). Several (12/40) upregulated proteins formed a cluster of inflammatory proteins with STAT1 and IRF3 as predicted upstream regulators. The several-fold increased expression of STAT1 and STAT-associated ISG15 was confirmed by immunoblotting. The expression of antioxidant proteins SOD1 and PRXD5 was downregulated suggesting radiation-induced oxidative stress. Similarly, the phosphorylated (active) forms of STING and IRF3, both members of the cGAS/STING pathway, were downregulated.Conclusions: These data suggest the involvement of JAK/STAT and cGas/STING pathways in the genesis of radiation-induced lung inflammation. These pathways may be used as novel targets for the prevention of radiation-induced lung damage.