Purpose: There is little information on the relative toxicity of highly charged (Z) high-energy (HZE) radiation in animal models compared to γ or X-rays, and the general assumption based on in vitro studies has been that acute toxicity is substantially greater.
Methods: C57BL/6J mice were irradiated with (56)Fe ions (1 GeV/nucleon), and acute (within 30 d) toxicity compared to that of γ rays or protons (1 GeV). To assess relative hematopoietic and gastrointestinal toxicity, the effects of (56)Fe ions were compared to γ rays using complete blood count (CBC), bone marrow granulocyte-macrophage colony forming unit (GM-CFU), terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay for apoptosis in bone marrow, and intestinal crypt survival.
Results: Although onset was more rapid, (56)Fe ions were only slightly more toxic than γ rays or protons with lethal dose (LD)(50/30) (a radiation dose at which 50% lethality occurs at 30-day) values of 5.8, 7.25, and 6.8 Gy, respectively, with relative biologic effectiveness for (56)Fe ions of 1.25 and 1.06 for protons.
Conclusions: (56)Fe radiation caused accelerated and more severe hematopoietic toxicity. Early mortality correlated with more profound leukopenia and subsequent sepsis. Results indicate that there is selective enhanced toxicity to bone marrow progenitor cells, which are typically resistant to γ rays, and bone marrow stem cells, because intestinal crypt cells did not show increased HZE toxicity.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3580183 | PMC |
| http://dx.doi.org/10.3109/09553002.2012.639434 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Comparative study of a microdosimetric biological weighting function for RBEmodeling in particle therapy with a solid state SOI microdosimeter.
Phys Med Biol
December 2024
Centre for Medical Radiation Physics, University of Wollongong, Northsfield Ave., Wollongong, New South Wales, 2522, AUSTRALIA.
The recently developed V79-RBEbiological weighting function (BWF) model is a simple and robust tool for a fast relative biological effectiveness (RBE) assessment for comparing different exposure conditions in particle therapy. In this study, the RBEderived by this model (through the Particle and Heavy Ion Transport code System (PHITS) simulated d(y) spectra) is compared with values of RBEusing experimentally derived d(y) spectra from a silicon-on-insulator (SOI) microdosimeter. Approach: Experimentally measured d(y) spectra are used to calculate an RBEvalue utilizing the V79-RBEBWF model as well as the modified microdosimetric kinetic model (MKM) to produce an RBE-vs-ytrend for a wide range of ions.
View Article and Find Full Text PDF56Fe-ion Exposure Increases the Incidence of Lung and Brain Tumors at a Similar Rate in Male and Female Mice.
Radiat Res
November 2024
Department of Radiation Oncology, Duke University School of Medicine, Durham, North Carolina.
The main deterrent to long-term space travel is the risk of Radiation Exposure Induced Death (REID). The National Aeronautics and Space Administration (NASA) has adopted Permissible Exposure Levels (PELs) to limit the probability of REID to 3% for the risk of death due to radiation-induced carcinogenesis. The most significant contributor to current REID estimates for astronauts is the risk of lung cancer.
View Article and Find Full Text PDFSpatial distribution of trace metals and associated transport proteins during bacterial infection.
Anal Bioanal Chem
May 2024
The Atomic Medicine Initiative, University of Technology Sydney, Broadway, New South Wales, Australia.
Innate immune systems alter the concentrations of trace elements in host niches in response to invading pathogens during infection. This work reports the interplay between d-block metal ions and their associated biomolecules using hyphenated elemental techniques to spatially quantify both elemental distributions and the abundance of specific transport proteins. Here, lung tissues were collected for analyses from naïve and Streptococcus pneumoniae-infected mice fed on a zinc-restricted or zinc-supplemented diet.
View Article and Find Full Text PDFEffects of HZE-Particle Exposure Location and Energy on Brain Inflammation and Oxidative Stress in Rats.
Radiat Res
November 2023
USDA-ARS, Human Nutrition Research Center on Aging at Tufts University, Boston, Maryland 02111.
Astronauts on exploratory missions will be exposed to particle radiation of high energy and charge (HZE particles), which have been shown to produce neurochemical and performance deficits in animal models. Exposure to HZE particles can produce both targeted effects, resulting from direct ionization of atoms along the particle track, and non-targeted effects (NTEs) in cells that are distant from the track, extending the range of potential damage beyond the site of irradiation. While recent work suggests that NTEs are primarily responsible for changes in cognitive function after HZE exposures, the relative contributions of targeted and non-targeted effects to neurochemical changes after HZE exposures are unclear.
View Article and Find Full Text PDFPostsynaptic density radiation signature following space irradiation.
Front Physiol
June 2023
Department of Behavioral Neuroscience, Oregon Health and Science University, Portland, OR, United States.
The response of the brain to space radiation is an important concern for astronauts during space missions. Therefore, we assessed the response of the brain to Si ion irradiation (600 MeV/n), a heavy ion present in the space environment, on cognitive performance and whether the response is associated with altered DNA methylation in the hippocampus, a brain area important for cognitive performance. We determined the effects of Si ion irradiation on object recognition, 6-month-old mice irradiated with Si ions (600 MeV/n, 0.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!