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Yun S, Kiffer FC, Bancroft GL, Guzman CS, Soler I, Haas HA, Shi R, Patel R, Lara-Jiménez J, Kumar PL, Tran FH, Ahn KJ, Rong Y, Luitel K, Shay JW, Eisch AJ. The longitudinal behavioral effects of acute exposure to galactic cosmic radiation in female C57BL/6J mice: implications for deep space missions, female crews, and potential antioxidant countermeasures. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.12.588768. [PMID: 38659963 PMCID: PMC11042186 DOI: 10.1101/2024.04.12.588768] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/26/2024]
Abstract
Galactic cosmic radiation (GCR) is an unavoidable risk to astronauts that may affect mission success. Male rodents exposed to 33-beam-GCR (33-GCR) show short-term cognitive deficits but reports on female rodents and long-term assessment is lacking. Here we asked: What are the longitudinal behavioral effects of 33-GCR on female mice? Also, can an antioxidant/anti-inflammatory compound mitigate the impact of 33-GCR? Mature (6-month-old) C57BL/6J female mice received the antioxidant CDDO-EA (400 µg/g of food) or a control diet (vehicle, Veh) for 5 days and either Sham-irradiation (IRR) or whole-body 33-GCR (0.75Gy) on the 4th day. Three-months post-IRR, mice underwent two touchscreen-platform tests: 1) location discrimination reversal (which tests behavior pattern separation and cognitive flexibility, two abilities reliant on the dentate gyrus) and 2) stimulus-response learning/extinction. Mice then underwent arena-based behavior tests (e.g. open field, 3-chamber social interaction). At the experiment end (14.25-month post-IRR), neurogenesis was assessed (doublecortin-immunoreactive [DCX+] dentate gyrus neurons). Female mice exposed to Veh/Sham vs. Veh/33-GCR had similar pattern separation (% correct to 1st reversal). There were two effects of diet: CDDO-EA/Sham and CDDO-EA/33-GCR mice had better pattern separation vs. their respective control groups (Veh/Sham, Veh/33-GCR), and CDDO-EA/33-GCR mice had better cognitive flexibility (reversal number) vs. Veh/33-GCR mice. Notably, one radiation effect/CDDO-EA countereffect also emerged: Veh/33-GCR mice had worse stimulus-response learning (days to completion) vs. all other groups, including CDDO-EA/33-GCR mice. In general, all mice show normal anxiety-like behavior, exploration, and habituation to novel environments. There was also a change in neurogenesis: Veh/33-GCR mice had fewer DCX+ dentate gyrus immature neurons vs. Veh/Sham mice. Our study implies space radiation is a risk to a female crew's longitudinal mission-relevant cognitive processes and CDDO-EA is a potential dietary countermeasure for space-radiation CNS risks.
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Britten RA, Fesshaye A, Tidmore A, Liu A, Blackwell AA. Loss of Cognitive Flexibility Practice Effects in Female Rats Exposed to Simulated Space Radiation. Radiat Res 2023; 200:256-265. [PMID: 37527363 DOI: 10.1667/rade-22-00196.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Accepted: 06/27/2023] [Indexed: 08/03/2023]
Abstract
During the planned missions to Mars, astronauts will be faced with many potential health hazards including prolonged exposure to space radiation. Ground-based studies have shown that exposure to space radiation impairs the performance of male rats in cognitive flexibility tasks which involve processes that are essential to rapidly and efficiently adapting to different situations. However, there is presently a paucity of information on the effects of space radiation on cognitive flexibility in female rodents. This study has determined the impact that exposure to a low (10 cGy) dose of ions from the simplified 5-ion galactic cosmic ray simulation [https://www.bnl.gov/nsrl/userguide/SimGCRSim.php (07/2023)] (GCRSim) beam or 250 MeV/n 4He ions has on the ability of female Wistar rats to perform in constrained [attentional set shifting (ATSET)] and unconstrained cognitive flexibility (UCFlex) tasks. Female rats exposed to GCRSim exhibited multiple decrements in ATSET performance. Firstly, GCRSim exposure impaired performance in the compound discrimination (CD) stage of the ATSET task. While the ability of rats to identify the rewarded cue was not compromised, the time the rats required to do so significantly increased. Secondly, both 4He and GCRSim exposure reduced the ability of rats to reach criterion in the compound discrimination reversal (CDR) stage. Approximately 20% of the irradiated rats were unable to complete the CDR task; furthermore, the irradiated rats that did reach criterion took more attempts to do so than did the sham-treated animals. Radiation exposure also altered the magnitude and/or nature of practice effects. A comparison of performance metrics from the pre-screen and post-exposure ATSET task revealed that while the sham-treated rats completed the post-exposure CD stage of the ATSET task in 30% less time than for completion of the pre-screen ATSET task, the irradiated rats took 30-50% longer to do so. Similarly, while sham-treated rats completed the CDR stage in ∼10% fewer attempts in the post-exposure task compared to the pre-screen task, in contrast, the 4He- and GCRSim-exposed cohorts took more (∼2-fold) attempts to reach criterion in the post-exposure task than in the pre-screen task. In conclusion, this study demonstrates that female rats are susceptible to radiation-induced loss of performance in the constrained ATSET cognitive flexibility task. Moreover, exposure to radiation leads to multiple performance decrements, including loss of practice effects, an increase in anterograde interference and reduced ability or unwillingness to switch attention. Should similar effects occur in humans, astronauts may have a compromised ability to perform complex tasks.
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Affiliation(s)
- Richard A Britten
- EVMS Radiation Oncology, Eastern Virginia Medical School, Norfolk, Virginia 23507
- EVMS Microbiology and Molecular Cell Biology, Eastern Virginia Medical School, Norfolk, Virginia 23507
- Center for Integrative Neuroscience and Inflammatory diseases, Eastern Virginia Medical School, Norfolk, Virginia 23507
| | - Arriyam Fesshaye
- EVMS Radiation Oncology, Eastern Virginia Medical School, Norfolk, Virginia 23507
| | - Alyssa Tidmore
- EVMS Radiation Oncology, Eastern Virginia Medical School, Norfolk, Virginia 23507
| | - Aiyi Liu
- EVMS Radiation Oncology, Eastern Virginia Medical School, Norfolk, Virginia 23507
| | - Ashley A Blackwell
- EVMS Radiation Oncology, Eastern Virginia Medical School, Norfolk, Virginia 23507
- Center for Integrative Neuroscience and Inflammatory diseases, Eastern Virginia Medical School, Norfolk, Virginia 23507
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Amelchenko EM, Bezriadnov DV, Chekhov OA, Ivanova AA, Kedrov AV, Anokhin KV, Lazutkin AA, Enikolopov G. Cognitive Flexibility Is Selectively Impaired by Radiation and Is Associated with Differential Recruitment of Adult-Born Neurons. J Neurosci 2023; 43:6061-6083. [PMID: 37532464 PMCID: PMC10451007 DOI: 10.1523/jneurosci.0161-22.2023] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Revised: 06/17/2023] [Accepted: 06/23/2023] [Indexed: 08/04/2023] Open
Abstract
Exposure to elevated doses of ionizing radiation, such as those in therapeutic procedures, catastrophic accidents, or space exploration, increases the risk of cognitive dysfunction. The full range of radiation-induced cognitive deficits is unknown, partly because commonly used tests may be insufficiently sensitive or may not be adequately tuned for assessing the fine behavioral features affected by radiation. Here, we asked whether γ-radiation might affect learning, memory, and the overall ability to adapt behavior to cope with a challenging environment (cognitive/behavioral flexibility). We developed a new behavioral assay, the context discrimination Morris water maze (cdMWM) task, which is hippocampus-dependent and requires the integration of various contextual cues and the adjustment of search strategies. We exposed male mice to 1 or 5 Gy of γ rays and, at different time points after irradiation, trained them consecutively in spatial MWM, reversal MWM, and cdMWM tasks, and assessed their learning, navigational search strategies, and memory. Mice exposed to 5 Gy performed successfully in the spatial and reversal MWM tasks; however, in the cdMWM task 6 or 8 weeks (but not 3 weeks) after irradiation, they demonstrated transient learning deficit, decreased use of efficient spatially precise search strategies during learning, and, 6 weeks after irradiation, memory deficit. We also observed impaired neurogenesis after irradiation and selective activation of 12-week-old newborn neurons by specific components of cdMWM training paradigm. Thus, our new behavioral paradigm reveals the effects of γ-radiation on cognitive flexibility and indicates an extended timeframe for the functional maturation of new hippocampal neurons.SIGNIFICANCE STATEMENT Exposure to radiation can affect cognitive performance and cognitive flexibility - the ability to adapt to changed circumstances and demands. The full range of consequences of irradiation on cognitive flexibility is unknown, partly because of a lack of suitable models. Here, we developed a new behavioral task requiring mice to combine various types of cues and strategies to find a correct solution. We show that animals exposed to γ-radiation, despite being able to successfully solve standard problems, show delayed learning, deficient memory, and diminished use of efficient navigation patterns in circumstances requiring adjustments of previously used search strategies. This new task could be applied in other settings for assessing the cognitive changes induced by aging, trauma, or disease.
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Affiliation(s)
- Evgeny M Amelchenko
- Center for Developmental Genetics
- Department of Anesthesiology, Stony Brook University, Stony Brook, New York 11794
| | - Dmitri V Bezriadnov
- P.K. Anokhin Research Institute of Normal Physiology, Moscow, 125315, Russian Federation
| | - Olga A Chekhov
- Center for Developmental Genetics
- Department of Anesthesiology, Stony Brook University, Stony Brook, New York 11794
| | - Anna A Ivanova
- Institute of Higher Nervous Activity and Neurophysiology RAS, Moscow, 117485, Russian Federation
- Institute for Advanced Brain Studies, Lomonosov Moscow State University, Moscow, 119234, Russian Federation
| | - Alexander V Kedrov
- P.K. Anokhin Research Institute of Normal Physiology, Moscow, 125315, Russian Federation
| | - Konstantin V Anokhin
- P.K. Anokhin Research Institute of Normal Physiology, Moscow, 125315, Russian Federation
- Institute for Advanced Brain Studies, Lomonosov Moscow State University, Moscow, 119234, Russian Federation
| | - Alexander A Lazutkin
- Center for Developmental Genetics
- Department of Anesthesiology, Stony Brook University, Stony Brook, New York 11794
- Institute of Higher Nervous Activity and Neurophysiology RAS, Moscow, 117485, Russian Federation
| | - Grigori Enikolopov
- Center for Developmental Genetics
- Department of Anesthesiology, Stony Brook University, Stony Brook, New York 11794
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Britten RA, Limoli CL. New Radiobiological Principles for the CNS Arising from Space Radiation Research. Life (Basel) 2023; 13:1293. [PMID: 37374076 DOI: 10.3390/life13061293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 05/17/2023] [Accepted: 05/29/2023] [Indexed: 06/29/2023] Open
Abstract
Traditionally, the brain has been regarded as a relatively insensitive late-reacting tissue, with radiologically detectable damage not being reported at doses < 60 Gy. When NASA proposed interplanetary exploration missions, it was required to conduct an intensive health and safety evaluation of cancer, cardiovascular, and cognitive risks associated with exposure to deep space radiation (SR). The SR dose that astronauts on a mission to Mars are predicted to receive is ~300 mGy. Even after correcting for the higher RBE of the SR particles, the biologically effective SR dose (<1 Gy) would still be 60-fold lower than the threshold dose for clinically detectable neurological damage. Unexpectedly, the NASA-funded research program has consistently reported that low (<250 mGy) doses of SR induce deficits in multiple cognitive functions. This review will discuss these findings and the radical paradigm shifts in radiobiological principles for the brain that were required in light of these findings. These included a shift from cell killing to loss of function models, an expansion of the critical brain regions for radiation-induced cognitive impediments, and the concept that the neuron may not be the sole critical target for neurocognitive impairment. The accrued information on how SR exposure impacts neurocognitive performance may provide new opportunities to reduce neurocognitive impairment in brain cancer patients.
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Affiliation(s)
- Richard A Britten
- EVMS Radiation Oncology, Eastern Virginia Medical School, Norfolk, VA 23507, USA
| | - Charles L Limoli
- Department Radiation Oncology, University of California-Irvine, Irvine, CA 92697, USA
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Stephenson S, Liu A, Blackwell AA, Britten RA. Multiple decrements in switch task performance in female rats exposed to space radiation. Behav Brain Res 2023; 449:114465. [PMID: 37142163 DOI: 10.1016/j.bbr.2023.114465] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Revised: 04/14/2023] [Accepted: 05/01/2023] [Indexed: 05/06/2023]
Abstract
Astronauts on the Artemis missions to the Moon and Mars will be exposed to unavoidable Galactic Cosmic Radiation (GCR). Studies using male rats suggest that GCR exposure impairs several processes required for cognitive flexibility performance, including attention and task switching. Currently no comparable studies have been conducted with female rats. Given that both males and females will travel into deep space, this study determined whether simulated GCR (GCRsim) exposure impairs task switching performance in female rats. Female Wistar rats exposed to 10cGy GCRsim (n = 12) and shams (n=14) were trained to perform a touchscreen-based switch task that mimics a switch task used to evaluate pilots' response times. In comparison to sham rats, three-fold more GCRsim-exposed rats failed to complete the stimulus response stage of training, a high cognitive loading task. In the switch task, 50% of the GCRsim-exposed rats failed to consistently transition between the repeated and switch blocks of stimuli, which they completed during lower cognitive loading training stages. The GCRsim-exposed rats that completed the switch task only performed at 65% of the accuracy of shams. Female rats exposed to GCRsim thus exhibit multiple decrements in the switch task under high, but not low, cognitive loading conditions. While the operational significance of this performance decrement is unknown, if GCRSim exposure was to induce similar effects in astronauts, our data suggests there may be a reduced ability to execute task switching under high cognitive loading situations.
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Affiliation(s)
- Samuel Stephenson
- School of Medicine, Eastern Virginia Medical School, Norfolk, Virginia 23507 USA
| | - Aiyi Liu
- EVMS Radiation Oncology, Eastern Virginia Medical School, Norfolk, Virginia 23507 USA
| | - Ashley A Blackwell
- EVMS Radiation Oncology, Eastern Virginia Medical School, Norfolk, Virginia 23507 USA; Center for Integrative Neuroscience and Inflammatory Diseases, Eastern Virginia Medical School, Norfolk, Virginia 23507 USA
| | - Richard A Britten
- EVMS Radiation Oncology, Eastern Virginia Medical School, Norfolk, Virginia 23507 USA; Center for Integrative Neuroscience and Inflammatory Diseases, Eastern Virginia Medical School, Norfolk, Virginia 23507 USA.
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Hinshaw RG, Schroeder MK, Ciola J, Varma C, Colletti B, Liu B, Liu GG, Shi Q, Williams JP, O’Banion MK, Caldarone BJ, Lemere CA. High-Energy, Whole-Body Proton Irradiation Differentially Alters Long-Term Brain Pathology and Behavior Dependent on Sex and Alzheimer's Disease Mutations. Int J Mol Sci 2023; 24:ijms24043615. [PMID: 36835027 PMCID: PMC9965515 DOI: 10.3390/ijms24043615] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2023] [Revised: 01/28/2023] [Accepted: 01/31/2023] [Indexed: 02/17/2023] Open
Abstract
Whole-body exposure to high-energy particle radiation remains an unmitigated hazard to human health in space. Ongoing experiments at the NASA Space Radiation Laboratory and elsewhere repeatedly show persistent changes in brain function long after exposure to simulations of this unique radiation environment, although, as is also the case with proton radiotherapy sequelae, how this occurs and especially how it interacts with common comorbidities is not well-understood. Here, we report modest differential changes in behavior and brain pathology between male and female Alzheimer's-like and wildtype littermate mice 7-8 months after exposure to 0, 0.5, or 2 Gy of 1 GeV proton radiation. The mice were examined with a battery of behavior tests and assayed for amyloid beta pathology, synaptic markers, microbleeds, microglial reactivity, and plasma cytokines. In general, the Alzheimer's model mice were more prone than their wildtype littermates to radiation-induced behavior changes, and hippocampal staining for amyloid beta pathology and microglial activation in these mice revealed a dose-dependent reduction in males but not in females. In summary, radiation-induced, long-term changes in behavior and pathology, although modest, appear specific to both sex and the underlying disease state.
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Affiliation(s)
- Robert G. Hinshaw
- Department of Neurology, Ann Romney Center for Neurologic Diseases, Brigham and Women’s Hospital, Boston, MA 02115, USA
- Harvard-MIT Division of Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, MA 02129, USA
| | - Maren K. Schroeder
- Department of Neurology, Ann Romney Center for Neurologic Diseases, Brigham and Women’s Hospital, Boston, MA 02115, USA
| | - Jason Ciola
- Department of Neurology, Ann Romney Center for Neurologic Diseases, Brigham and Women’s Hospital, Boston, MA 02115, USA
| | - Curran Varma
- Department of Neurology, Ann Romney Center for Neurologic Diseases, Brigham and Women’s Hospital, Boston, MA 02115, USA
| | - Brianna Colletti
- Department of Neurology, Ann Romney Center for Neurologic Diseases, Brigham and Women’s Hospital, Boston, MA 02115, USA
| | - Bin Liu
- Department of Neurology, Ann Romney Center for Neurologic Diseases, Brigham and Women’s Hospital, Boston, MA 02115, USA
- Departments of Neurology, Harvard Medical School, Boston, MA 02115, USA
| | - Grace Geyu Liu
- Department of Neurology, Ann Romney Center for Neurologic Diseases, Brigham and Women’s Hospital, Boston, MA 02115, USA
| | - Qiaoqiao Shi
- Department of Neurology, Ann Romney Center for Neurologic Diseases, Brigham and Women’s Hospital, Boston, MA 02115, USA
- Departments of Neurology, Harvard Medical School, Boston, MA 02115, USA
| | - Jacqueline P. Williams
- Department of Environmental Medicine, University of Rochester Medical Center, Rochester, NY 14642, USA
| | - M. Kerry O’Banion
- Department of Neuroscience, Del Monte Institute of Neuroscience, University of Rochester Medical Center, Rochester, NY 14642, USA
| | | | - Cynthia A. Lemere
- Department of Neurology, Ann Romney Center for Neurologic Diseases, Brigham and Women’s Hospital, Boston, MA 02115, USA
- Departments of Neurology, Harvard Medical School, Boston, MA 02115, USA
- Correspondence:
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Comparative Analysis of Behavioral Reactions and Morphological Changes in the Rat Brain After Exposure to Ionizing Radiation with Different Physical Characteristics. Cell Mol Neurobiol 2023; 43:339-353. [PMID: 34982311 DOI: 10.1007/s10571-021-01187-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Accepted: 12/24/2021] [Indexed: 01/11/2023]
Abstract
The aim of this research was to study behavioral reactions and morphological changes in the brain of adult female Sprague Dawley rats after exposure to 170 MeV and 70 MeV protons and gamma radiation (60Co) at a dose of 1 Gy. The analysis of the behavioral reactions in the T-maze showed that exposure to ionizing radiation with different LETs led to an increase in number of repeated entries into the arms of the maze in the spontaneous alternation test. In the Open Field test a decrease in overall motor activity in the group of irradiated animals (70 MeV protons at the Bragg peak) was observed. A decrease in the number of standing positions was seen in all groups of irradiated animals. Morphological analysis showed the development of early amyloidosis, autolysis of the ependymal layer, an increase in the number of neurodegenerative changes in various structures of the brain, and the development of neuronal hypertrophy on the 30th day after irradiation in the cerebellum and hippocampal hilus. Exposure to protons at a dose of 1 Gy leads to the development of structural and functional disorders of the central nervous system of animals on the 30th day after irradiation. These data indicate a damage of short-term memory, a decrease in motor activity and exploratory behavior of animals. With an increase in LET, there is an increase in the number of amyloid plaques in the forebrain of rats, autolysis of the ependymal layer of the ventricles, and the development of dystrophic changes. Investigations of behavioral reactions and morphological changes in various parts of the brain of adult rats on the 30th day after influence of ionizing radiation with different physical characteristics at a dose of 1 Gy. Various negative patho-morphological and cognitive-behavioral changes observed.
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Peter JS, Schuemann J, Held KD, McNamara AL. Nano-scale simulation of neuronal damage by galactic cosmic rays. Phys Med Biol 2022; 67:10.1088/1361-6560/ac95f4. [PMID: 36172820 PMCID: PMC9951267 DOI: 10.1088/1361-6560/ac95f4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Accepted: 09/28/2022] [Indexed: 11/11/2022]
Abstract
The effects of realistic, deep space radiation environments on neuronal function remain largely unexplored.In silicomodeling studies of radiation-induced neuronal damage provide important quantitative information about physico-chemical processes that are not directly accessible through radiobiological experiments. Here, we present the first nano-scale computational analysis of broad-spectrum galactic cosmic ray irradiation in a realistic neuron geometry. We constructed thousands ofin silicorealizations of a CA1 pyramidal neuron, each with over 3500 stochastically generated dendritic spines. We simulated the entire 33 ion-energy beam spectrum currently in use at the NASA Space Radiation Laboratory galactic cosmic ray simulator (GCRSim) using the TOol for PArticle Simulation (TOPAS) and TOPAS-nBio Monte Carlo-based track structure simulation toolkits. We then assessed the resulting nano-scale dosimetry, physics processes, and fluence patterns. Additional comparisons were made to a simplified 6 ion-energy spectrum (SimGCRSim) also used in NASA experiments. For a neuronal absorbed dose of 0.5 Gy GCRSim, we report an average of 250 ± 10 ionizations per micrometer of dendritic length, and an additional 50 ± 10, 7 ± 2, and 4 ± 2 ionizations per mushroom, thin, and stubby spine, respectively. We show that neuronal energy deposition by proton andα-particle tracks declines approximately hyperbolically with increasing primary particle energy at mission-relevant energies. We demonstrate an inverted exponential relationship between dendritic segment irradiation probability and neuronal absorbed dose for each ion-energy beam. We also find that there are no significant differences in the average physical responses between the GCRSim and SimGCRSim spectra. To our knowledge, this is the first nano-scale simulation study of a realistic neuron geometry using the GCRSim and SimGCRSim spectra. These results may be used as inputs to theoretical models, aid in the interpretation of experimental results, and help guide future study designs.
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Affiliation(s)
- Jonah S Peter
- Biophysics Program, Harvard University, Boston, MA 02115, United States of America
- Department of Radiation Oncology, Massachusetts General Hospital & Harvard Medical School, Boston, MA 02114, United States of America
| | - Jan Schuemann
- Department of Radiation Oncology, Massachusetts General Hospital & Harvard Medical School, Boston, MA 02114, United States of America
| | - Kathryn D Held
- Department of Radiation Oncology, Massachusetts General Hospital & Harvard Medical School, Boston, MA 02114, United States of America
| | - Aimee L McNamara
- Department of Radiation Oncology, Massachusetts General Hospital & Harvard Medical School, Boston, MA 02114, United States of America
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Laiakis EC, Pinheiro M, Nguyen T, Nguyen H, Beheshti A, Dutta SM, Russell WK, Emmett MR, Britten RA. Quantitative proteomic analytic approaches to identify metabolic changes in the medial prefrontal cortex of rats exposed to space radiation. Front Physiol 2022; 13:971282. [PMID: 36091373 PMCID: PMC9459391 DOI: 10.3389/fphys.2022.971282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2022] [Accepted: 07/20/2022] [Indexed: 11/13/2022] Open
Abstract
NASA’s planned mission to Mars will result in astronauts being exposed to ∼350 mSv/yr of Galactic Cosmic Radiation (GCR). A growing body of data from ground-based experiments indicates that exposure to space radiation doses (approximating those that astronauts will be exposed to on a mission to Mars) impairs a variety of cognitive processes, including cognitive flexibility tasks. Some studies report that 33% of individuals may experience severe cognitive impairment. Translating the results from ground-based rodent studies into tangible risk estimates for astronauts is an enormous challenge, but it would be germane for NASA to use the vast body of data from the rodent studies to start developing appropriate countermeasures, in the expectation that some level of space radiation (SR) -induced cognitive impairment could occur in astronauts. While some targeted studies have reported radiation-induced changes in the neurotransmission properties and/or increased neuroinflammation within space radiation exposed brains, there remains little information that can be used to start the development of a mechanism-based countermeasure strategy. In this study, we have employed a robust label-free mass spectrometry (MS) -based untargeted quantitative proteomic profiling approach to characterize the composition of the medial prefrontal cortex (mPFC) proteome in rats that have been exposed to 15 cGy of 600 MeV/n28Si ions. A variety of analytical techniques were used to mine the generated expression data, which in such studies is typically hampered by low and variable sample size. We have identified several pathways and proteins whose expression alters as a result of space radiation exposure, including decreased mitochondrial function, and a further subset of proteins differs in rats that have a high level of cognitive performance after SR exposure in comparison with those that have low performance levels. While this study has provided further insight into how SR impacts upon neurophysiology, and what adaptive responses can be invoked to prevent the emergence of SR-induced cognitive impairment, the main objective of this paper is to outline strategies that can be used by others to analyze sub-optimal data sets and to identify new information.
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Affiliation(s)
- Evagelia C. Laiakis
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University, Washington, DC, United States
- Department of Biochemistry and Molecular & Cellular Biology, Georgetown University, Washington, DC, United States
- *Correspondence: Evagelia C. Laiakis,
| | - Maisa Pinheiro
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, Rockville, MD, United States
| | - Tin Nguyen
- Department of Computer Science and Engineering, University of Nevada, Reno, NV, United States
| | - Hung Nguyen
- Department of Computer Science and Engineering, University of Nevada, Reno, NV, United States
| | - Afshin Beheshti
- KBR, Space Biosciences Division, NASA Ames Research Center, Moffett Field, Mountain View, CA, United States
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA, United States
| | - Sucharita M. Dutta
- Department of Obstetrics and Gynecology, Eastern Virginia Medical School, Norfolk, VA, United States
| | - William K. Russell
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX, United States
| | - Mark R. Emmett
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX, United States
- Department of Radiation Oncology, University of Texas Medical Branch, Galveston, TX, United States
| | - Richard A. Britten
- Department of Radiation Oncology, Eastern Virginia Medical School, Norfolk, VA, United States
- Department of Microbiology and Molecular Cell Biology, Eastern Virginia Medical School, Norfolk, VA, United States
- Center for Integrative Neuroinflammatory and Inflammatory Diseases, Eastern Virginia Medical School, Norfolk, VA, United States
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Risk of Developing Non-Cancerous Central Nervous System Diseases Due to Ionizing Radiation Exposure during Adulthood: Systematic Review and Meta-Analyses. Brain Sci 2022; 12:brainsci12080984. [PMID: 35892428 PMCID: PMC9331299 DOI: 10.3390/brainsci12080984] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Revised: 07/20/2022] [Accepted: 07/22/2022] [Indexed: 02/01/2023] Open
Abstract
Background: High-dose ionizing radiation (IR) (>0.5 Gy) is an established risk factor for cognitive impairments, but this cannot be concluded for low-to-moderate IR exposure (<0.5 Gy) in adulthood as study results are inconsistent. The objectives are to summarize relevant epidemiological studies of low-to-moderate IR exposure in adulthood and to assess the risk of non-cancerous CNS diseases. Methods: A systematic literature search of four electronic databases was performed to retrieve relevant epidemiological studies published from 2000 to 2022. Pooled standardized mortality ratios, relative risks, and excess relative risks (ERR) were estimated with a random effect model. Results: Forty-five publications were included in the systematic review, including thirty-three in the quantitative meta-analysis. The following sources of IR-exposure were considered: atomic bomb, occupational, environmental, and medical exposure. Increased dose-risk relationships were found for cerebrovascular diseases incidence and mortality (ERRpooled per 100 mGy = 0.04; 95% CI: 0.03−0.05; ERRpooled at 100 mGy = 0.01; 95% CI: −0.00−0.02, respectively) and for Parkinson’s disease (ERRpooled at 100 mGy = 0.11; 95% CI: 0.06−0.16); Conclusions: Our findings suggest that adult low-to-moderate IR exposure may have effects on non-cancerous CNS diseases. Further research addressing inherent variation issues is encouraged.
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Ton ST, Laghi JR, Tsai SY, Blackwell AA, Adamczyk NS, Oltmanns JRO, Britten RA, Wallace DG, Kartje GL. Exposure to 5 cGy 28Si Particles Induces Long-Term Microglial Activation in the Striatum and Subventricular Zone and Concomitant Neurogenic Suppression. Radiat Res 2022; 198:28-39. [DOI: 10.1667/rade-21-00021.1] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Accepted: 03/17/2022] [Indexed: 11/03/2022]
Abstract
The proposed mission to Mars will expose astronauts to space radiation that is known to adversely affect cognition and tasks that rely on fine sensorimotor function. Space radiation has also been shown to affect the microglial and neurogenic responses in the center nervous system (CNS). We recently reported that a low dose of 5 cGy 600 MeV/n 28Si results in impaired cognition and skilled motor behavior in adult rats. Since these tasks rely at least in part on the proper functioning of the striatum, we examined striatal microglial cells in these same subjects. Using morphometric analysis, we found that 28Si exposure increased activated microglial cells in the striatum. The majority of these striatal Iba1+ microglia were ED1–, indicating that they were in an alternatively activated state, where microglia do not have phagocytic activity but may be releasing cytokines that could negatively impact neuronal function. In the other areas studied, Iba1+ microglial cells were increased in the subventricular zone (SVZ), but not in the dentate gyrus (DG). Additionally, we examined the relationship between the microglial response and neurogenesis. An analysis of new neurons in the DG revealed an increase in doublecortin-positive (DCX+) hilar ectopic granule cells (hEGC) which correlated with Iba1+ cells, suggesting that microglial cells contributed to this aberrant distribution which may adversely affect hippocampal function. Taken together, these results indicate that a single dose of 28Si radiation results in persistent cellular effects in the CNS that may impact astronauts both in the short and long-term following deep space missions.
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Affiliation(s)
- Son T. Ton
- Research Service, Edward Hines Jr. VA Hospital, Hines, Illinois
| | - Julia R. Laghi
- Research Service, Edward Hines Jr. VA Hospital, Hines, Illinois
| | - Shih-Yen Tsai
- Research Service, Edward Hines Jr. VA Hospital, Hines, Illinois
| | | | | | | | - Richard A. Britten
- Department of Radiation Oncology, Eastern Virginia Medical School, Norfolk, Virginia
| | - Douglas G. Wallace
- Department of Psychology, Northern Illinois University, DeKalb, Illinois
| | - Gwendolyn L. Kartje
- Research Service, Edward Hines Jr. VA Hospital, Hines, Illinois
- Department of Molecular Pharmacology and Neuroscience, Loyola University Chicago Health Sciences Division, Maywood, Illinois
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12
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Kiffer FC, Luitel K, Tran FH, Patel RA, Guzman CS, Soler I, Xiao R, Shay JW, Yun S, Eisch AJ. Effects of a 33-ion sequential beam galactic cosmic ray analog on male mouse behavior and evaluation of CDDO-EA as a radiation countermeasure. Behav Brain Res 2022; 419:113677. [PMID: 34818568 PMCID: PMC9755463 DOI: 10.1016/j.bbr.2021.113677] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Revised: 10/28/2021] [Accepted: 11/16/2021] [Indexed: 12/21/2022]
Abstract
In long-term spaceflight, astronauts will face unique cognitive loads and social challenges which will be complicated by communication delays with Earth. It is important to understand the central nervous system (CNS) effects of deep spaceflight and the associated unavoidable exposure to galactic cosmic radiation (GCR). Rodent studies show single- or simple-particle combination exposure alters CNS endpoints, including hippocampal-dependent behavior. An even better Earth-based simulation of GCR is now available, consisting of a 33-beam (33-GCR) exposure. However, the effect of whole-body 33-GCR exposure on rodent behavior is unknown, and no 33-GCR CNS countermeasures have been tested. Here astronaut-age-equivalent (6mo-old) C57BL/6J male mice were exposed to 33-GCR (75cGy, a Mars mission dose). Pre-/during/post-Sham or 33-GCR exposure, mice received a diet containing a 'vehicle' formulation alone or with the antioxidant/anti-inflammatory compound CDDO-EA as a potential countermeasure. Behavioral testing beginning 4mo post-irradiation suggested radiation and diet did not affect measures of exploration/anxiety-like behaviors (open field, elevated plus maze) or recognition of a novel object. However, in 3-Chamber Social Interaction (3-CSI), CDDO-EA/33-GCR mice failed to spend more time exploring a holder containing a novel mouse vs. a novel object (empty holder), suggesting sociability deficits. Also, Vehicle/33-GCR and CDDO-EA/Sham mice failed to discriminate between a novel stranger vs. familiarized stranger mouse, suggesting blunted preference for social novelty. CDDO-EA given pre-/during/post-irradiation did not attenuate the 33-GCR-induced blunting of preference for social novelty. Future elucidation of the mechanisms underlying 33-GCR-induced blunting of preference for social novelty will improve risk analysis for astronauts which may in-turn improve countermeasures.
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Affiliation(s)
- Frederico C Kiffer
- Department of Anesthesiology and Critical Care Medicine, The Children’s Hospital of Philadelphia (CHOP) Research Institute, Philadelphia, PA, USA, 19104
| | - Krishna Luitel
- Department of Cell Biology, University of Texas Southwestern (UTSW) Medical Center, Dallas, TX, USA, 75390
| | - Fionya H Tran
- Department of Anesthesiology and Critical Care Medicine, The Children’s Hospital of Philadelphia (CHOP) Research Institute, Philadelphia, PA, USA, 19104
| | - Riya A Patel
- Department of Anesthesiology and Critical Care Medicine, The Children’s Hospital of Philadelphia (CHOP) Research Institute, Philadelphia, PA, USA, 19104
| | - Catalina S Guzman
- Department of Anesthesiology and Critical Care Medicine, The Children’s Hospital of Philadelphia (CHOP) Research Institute, Philadelphia, PA, USA, 19104
| | - Ivan Soler
- Department of Anesthesiology and Critical Care Medicine, The Children’s Hospital of Philadelphia (CHOP) Research Institute, Philadelphia, PA, USA, 19104
| | - Rui Xiao
- Department of Pediatrics Division of Biostatistics, CHOP Research Institute, Philadelphia, PA, USA, 19104,Department of Biostatistics, Epidemiology & Informatics, University of Pennsylvania, Philadelphia, PA, USA, 19104
| | - Jerry W Shay
- Department of Cell Biology, University of Texas Southwestern (UTSW) Medical Center, Dallas, TX, USA, 75390
| | - Sanghee Yun
- Department of Anesthesiology and Critical Care Medicine, The Children’s Hospital of Philadelphia (CHOP) Research Institute, Philadelphia, PA, USA, 19104,Department of Neuroscience, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA, 19104
| | - Amelia J Eisch
- Department of Anesthesiology and Critical Care Medicine, The Children's Hospital of Philadelphia (CHOP) Research Institute, Philadelphia, PA 19104, USA; Department of Neuroscience, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA.
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13
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Britten RA, Wellman LL, Sanford LD. Progressive increase in the complexity and translatability of rodent testing to assess space-radiation induced cognitive impairment. Neurosci Biobehav Rev 2021; 126:159-174. [PMID: 33766676 DOI: 10.1016/j.neubiorev.2021.01.027] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Revised: 12/15/2020] [Accepted: 01/07/2021] [Indexed: 11/29/2022]
Abstract
Ground-based rodent models have established that space radiation doses (approximately those that astronauts will be exposed to on a mission to Mars) significantly impair performance in a wide range of cognitive tasks. Over the last 40 years there has been a progressive increase in both the complexity and the translatability (to humans) of the cognitive tasks investigated. This review outlines technical and conceptual advances in space radiation rodent testing approaches, along with the advances in analytical approaches, that will make data from ground based studies more amenable to probabilistic risk analysis. While great progress has been made in determining the impact of space radiation on many advanced cognitive processes, challenges remain that need to be addressed prior to commencing deep space missions. A summary of on-going attempts to address existing knowledge gaps and the critical role that rodent studies will have in establishing the impact of space radiation on even more complex (human) cognitive tasks are presented and discussed.
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Affiliation(s)
- Richard A Britten
- Department of Radiation Oncology, Eastern Virginia Medical School, Norfolk, VA, 23507, USA; Department of Microbiology and Molecular Cell Biology, Eastern Virginia Medical School, Norfolk, VA, 23507, USA; Leroy T Canoles Jr. Cancer Center, Eastern Virginia Medical School, Norfolk, VA, 23507, USA; Center for Integrative Neuroscience and Inflammatory Diseases, Eastern Virginia Medical School, Norfolk, VA, 23507, USA.
| | - Laurie L Wellman
- Center for Integrative Neuroscience and Inflammatory Diseases, Eastern Virginia Medical School, Norfolk, VA, 23507, USA; Department of Pathology & Anatomy, Eastern Virginia Medical School, Norfolk, VA, 23507, USA
| | - Larry D Sanford
- Center for Integrative Neuroscience and Inflammatory Diseases, Eastern Virginia Medical School, Norfolk, VA, 23507, USA; Department of Pathology & Anatomy, Eastern Virginia Medical School, Norfolk, VA, 23507, USA
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14
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Davis CM, Allen AR, Bowles DE. Consequences of space radiation on the brain and cardiovascular system. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART C, TOXICOLOGY AND CARCINOGENESIS 2021; 39:180-218. [PMID: 33902387 DOI: 10.1080/26896583.2021.1891825] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Staying longer in outer space will inevitably increase the health risks of astronauts due to the exposures to galactic cosmic rays and solar particle events. Exposure may pose a significant hazard to space flight crews not only during the mission but also later, when slow-developing adverse effects could finally become apparent. The body of literature examining ground-based outcomes in response to high-energy charged-particle radiation suggests differential effects in response to different particles and energies. Numerous animal and cellular models have repeatedly demonstrated the negative effects of high-energy charged-particle on the brain and cognitive function. However, research on the role of space radiation in potentiating cardiovascular dysfunction is still in its early stages. This review summarizes the available data from studies using ground-based animal models to evaluate the response of the brain and heart to the high-energy charged particles of GCR and SPE, addresses potential sex differences in these effects, and aims to highlight gaps in the current literature for future study.
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Affiliation(s)
- Catherine M Davis
- Department of Pharmacology and Molecular Therapeutics, Uniformed Services University of the Health Sciences Bethesda, MD, USA
| | - Antiño R Allen
- Division of Radiation Health, University of Arkansas for Medical Sciences, Little Rock, AR, USA
- Department of Pharmaceutical Sciences, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - Dawn E Bowles
- Division of Surgical Sciences, Department of Surgery, Duke University, Durham, NC, USA
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15
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Willey JS, Britten RA, Blaber E, Tahimic CG, Chancellor J, Mortreux M, Sanford LD, Kubik AJ, Delp MD, Mao XW. The individual and combined effects of spaceflight radiation and microgravity on biologic systems and functional outcomes. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART C, TOXICOLOGY AND CARCINOGENESIS 2021; 39:129-179. [PMID: 33902391 PMCID: PMC8274610 DOI: 10.1080/26896583.2021.1885283] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Both microgravity and radiation exposure in the spaceflight environment have been identified as hazards to astronaut health and performance. Substantial study has been focused on understanding the biology and risks associated with prolonged exposure to microgravity, and the hazards presented by radiation from galactic cosmic rays (GCR) and solar particle events (SPEs) outside of low earth orbit (LEO). To date, the majority of the ground-based analogues (e.g., rodent or cell culture studies) that investigate the biology of and risks associated with spaceflight hazards will focus on an individual hazard in isolation. However, astronauts will face these challenges simultaneously Combined hazard studies are necessary for understanding the risks astronauts face as they travel outside of LEO, and are also critical for countermeasure development. The focus of this review is to describe biologic and functional outcomes from ground-based analogue models for microgravity and radiation, specifically highlighting the combined effects of radiation and reduced weight-bearing from rodent ground-based tail suspension via hind limb unloading (HLU) and partial weight-bearing (PWB) models, although in vitro and spaceflight results are discussed as appropriate. The review focuses on the skeletal, ocular, central nervous system (CNS), cardiovascular, and stem cells responses.
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Affiliation(s)
| | | | - Elizabeth Blaber
- Department of Biomedical Engineering, Rensselaer Polytechnic Institute
| | | | | | - Marie Mortreux
- Department of Neurology, Harvard Medical School, Beth Israel Deaconess Medical Center
| | - Larry D. Sanford
- Department of Radiation Oncology, Eastern Virginia Medical School
| | - Angela J. Kubik
- Department of Biomedical Engineering, Rensselaer Polytechnic Institute
| | - Michael D. Delp
- Department of Nutrition, Food and Exercise Sciences, Florida State University
| | - Xiao Wen Mao
- Division of Biomedical Engineering Sciences (BMES), Department of Basic Sciences, Loma Linda University
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16
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Britten RA, Fesshaye AS, Duncan VD, Wellman LL, Sanford LD. Sleep Fragmentation Exacerbates Executive Function Impairments Induced by Low Doses of Si Ions. Radiat Res 2020; 194:116-123. [PMID: 32845991 DOI: 10.1667/rade-20-00080.1] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Accepted: 05/22/2020] [Indexed: 11/03/2022]
Abstract
Astronauts on deep space missions will be required to work autonomously and thus their ability to perform executive functions could be critical to mission success. Ground-based rodent experiments have shown that low (<25 cGy) doses of several space radiation (SR) ions impair various aspects of executive function. Translating ground-based rodent studies into tangible risk estimates for astronauts remains an enormous challenge, but should similar neurocognitive impairments occur in astronauts exposed to low-SR doses, a Numbers-Needed-to-Harm analysis (of the rodent data) predicts that approximately 30% of the astronauts could develop severe cognitive flexibility decrements. In addition to the health risks associated with SR exposure, astronauts have to contend with other stressors, of which inadequate sleep quantity and quality are considered to be major concerns. We have shown that a single session of fragmented sleep uncovered latent attentional set-shifting (ATSET) performance deficits in rats exposed to protracted neutron radiation that had no obvious defects in performance under rested wakefulness conditions. It is unclear if the exacerbating effect of sleep fragmentation (SF) only occurs in rats receiving protracted low-dose-rate-neutron radiation. In this study, we assessed whether SF also unmasks latent ATSET deficits in rats exposed to 5 cGy 600 MeV/n 28Si ions. Only sham and Si-irradiated rats that had good ATSET performance (passing every stage of the test on their first attempt) were selected for study. Sleep fragmentation selectively impaired performance in the more complex IDR, EDS and EDR stages of the ATSET test in the Si-irradiated rats. Set-shifting performance has rarely been affected by SR exposure in our studies conducted with rats tested under rested wakefulness conditions. The consistent SF-related unmasking of latent set-shifting deficits in both Si- and neutron-irradiated rats suggests that there is a unique interaction between sleep fragmentation and space radiation on the functionality of the brain regions that regulate performance in the IDR, EDS and EDR stages of ATSET. The uncovering of these latent SR-induced ATSET performance deficits in both Si- and neutron-irradiated rats suggests that the true impact of SR-induced cognitive impairment may not be fully evident in normally rested rats, and thus cognitive testing needs to be conducted under both rested wakefulness and sleep fragmentation conditions.
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Affiliation(s)
- Richard A Britten
- Departments of a Radiation Oncology.,Departments of Microbiology and Molecular Cell Biology.,Center for Integrative Neuroscience and Inflammatory Diseases.,Leroy T. Canoles Jr. Cancer Center
| | | | | | - Laurie L Wellman
- Center for Integrative Neuroscience and Inflammatory Diseases.,Department of Pathology and Anatomy, Eastern Virginia Medical School, Norfolk, Virginia 23507
| | - Larry D Sanford
- Center for Integrative Neuroscience and Inflammatory Diseases.,Department of Pathology and Anatomy, Eastern Virginia Medical School, Norfolk, Virginia 23507
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17
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Blackwell AA, Schell BD, Osterlund Oltmanns JR, Whishaw IQ, Ton ST, Adamczyk NS, Kartje GL, Britten RA, Wallace DG. Skilled movement and posture deficits in rat string-pulling behavior following low dose space radiation ( 28Si) exposure. Behav Brain Res 2020; 400:113010. [PMID: 33181183 DOI: 10.1016/j.bbr.2020.113010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2020] [Revised: 10/21/2020] [Accepted: 11/05/2020] [Indexed: 10/23/2022]
Abstract
Deep space flight missions beyond the Van Allen belt have the potential to expose astronauts to space radiation which may damage the central nervous system and impair function. The proposed mission to Mars will be the longest mission-to-date and identifying mission critical tasks that are sensitive to space radiation is important for developing and evaluating the efficacy of counter measures. Fine motor control has been assessed in humans, rats, and many other species using string-pulling behavior. For example, focal cortical damage has been previously shown to disrupt the topographic (i.e., path circuity) and kinematic (i.e., moment-to-moment speed) organization of rat string-pulling behavior count to compromise task accuracy. In the current study, rats were exposed to a ground-based model of simulated space radiation (5 cGy 28Silicon), and string-pulling behavior was used to assess fine motor control. Irradiated rats initially took longer to pull an unweighted string into a cage, exhibited impaired accuracy in grasping the string, and displayed postural deficits. Once rats were switched to a weighted string, some deficits lessened but postural instability remained. These results demonstrate that a single exposure to a low dose of space radiation disrupts skilled hand movements and posture, suggestive of neural impairment. This work establishes a foundation for future studies to investigate the neural structures and circuits involved in fine motor control and to examine the effectiveness of counter measures to attenuate the effects of space radiation on fine motor control.
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Affiliation(s)
- Ashley A Blackwell
- Department of Psychology, Northern Illinois University, DeKalb, IL, 60115, United States.
| | - Brandi D Schell
- Department of Psychology, Northern Illinois University, DeKalb, IL, 60115, United States
| | | | - Ian Q Whishaw
- Canadian Centre for Behavioural Neuroscience, University of Lethbridge, Lethbridge, Alberta, Canada
| | - Son T Ton
- Research Service, Edward Hines Jr. VA Hospital, Hines, IL, 60141, United States; Department of Molecular Pharmacology and Neuroscience, Loyola University Chicago Health Sciences Division, Maywood, IL, 60153, United States
| | - Natalie S Adamczyk
- Research Service, Edward Hines Jr. VA Hospital, Hines, IL, 60141, United States
| | - Gwendolyn L Kartje
- Research Service, Edward Hines Jr. VA Hospital, Hines, IL, 60141, United States; Department of Molecular Pharmacology and Neuroscience, Loyola University Chicago Health Sciences Division, Maywood, IL, 60153, United States
| | - Richard A Britten
- Department of Radiation Oncology, Eastern Virginia Medical School, Norfolk, VA, 23507, United States
| | - Douglas G Wallace
- Department of Psychology, Northern Illinois University, DeKalb, IL, 60115, United States
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18
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Azzam P, Mroueh M, Francis M, Daher AA, Zeidan YH. Radiation-induced neuropathies in head and neck cancer: prevention and treatment modalities. Ecancermedicalscience 2020; 14:1133. [PMID: 33281925 PMCID: PMC7685771 DOI: 10.3332/ecancer.2020.1133] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2020] [Indexed: 12/24/2022] Open
Abstract
Head and neck cancer (HNC) is the sixth most common human malignancy with a global incidence of 650,000 cases per year. Radiotherapy (RT) is commonly used as an effective therapy to treat tumours as a definitive or adjuvant treatment. Despite the substantial advances in RT contouring and dosage delivery, patients suffer from various radiation-induced complications, among which are toxicities to the nervous tissues in the head and neck area. Radiation-mediated neuropathies manifest as a result of increased oxidative stress-mediated apoptosis, neuroinflammation and altered cellular function in the nervous tissues. Eventually, molecular damage results in the formation of fibrotic tissues leading to susceptible loss of function of numerous neuronal substructures. Neuropathic sequelae following irradiation in the head and neck area include sensorineural hearing loss, alterations in taste and smell functions along with brachial plexopathy, and cranial nerves palsies. Numerous management options are available to relieve radiation-associated neurotoxicities notwithstanding treatment alternatives that remain restricted with limited benefits. In the scope of this review, we discuss the use of variable management and therapeutic modalities to palliate common radiation-induced neuropathies in head and neck cancers.
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Affiliation(s)
- Patrick Azzam
- Department of Anatomy, Cell Biology and Physiology, Faculty of Medicine, American University of Beirut, Beirut 1107 2020, Lebanon
| | - Manal Mroueh
- Department of Anatomy, Cell Biology and Physiology, Faculty of Medicine, American University of Beirut, Beirut 1107 2020, Lebanon
| | - Marina Francis
- Department of Anatomy, Cell Biology and Physiology, Faculty of Medicine, American University of Beirut, Beirut 1107 2020, Lebanon
| | - Alaa Abou Daher
- Department of Anatomy, Cell Biology and Physiology, Faculty of Medicine, American University of Beirut, Beirut 1107 2020, Lebanon
| | - Youssef H Zeidan
- Department of Anatomy, Cell Biology and Physiology, Faculty of Medicine, American University of Beirut, Beirut 1107 2020, Lebanon
- Department of Radiation Oncology, American University of Beirut Medical Center, Beirut 1107 2020, Lebanon
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19
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Allen BD, Syage AR, Maroso M, Baddour AAD, Luong V, Minasyan H, Giedzinski E, West BL, Soltesz I, Limoli CL, Baulch JE, Acharya MM. Mitigation of helium irradiation-induced brain injury by microglia depletion. J Neuroinflammation 2020; 17:159. [PMID: 32429943 PMCID: PMC7236926 DOI: 10.1186/s12974-020-01790-9] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Accepted: 03/26/2020] [Indexed: 12/11/2022] Open
Abstract
Background Cosmic radiation exposures have been found to elicit cognitive impairments involving a wide-range of underlying neuropathology including elevated oxidative stress, neural stem cell loss, and compromised neuronal architecture. Cognitive impairments have also been associated with sustained microglia activation following low dose exposure to helium ions. Space-relevant charged particles elicit neuroinflammation that persists long-term post-irradiation. Here, we investigated the potential neurocognitive benefits of microglia depletion following low dose whole body exposure to helium ions. Methods Adult mice were administered a dietary inhibitor (PLX5622) of colony stimulating factor-1 receptor (CSF1R) to deplete microglia 2 weeks after whole body helium irradiation (4He, 30 cGy, 400 MeV/n). Cohorts of mice maintained on a normal and PLX5622 diet were tested for cognitive function using seven independent behavioral tasks, microglial activation, hippocampal neuronal morphology, spine density, and electrophysiology properties 4–6 weeks later. Results PLX5622 treatment caused a rapid and near complete elimination of microglia in the brain within 3 days of treatment. Irradiated animals on normal diet exhibited a range of behavioral deficits involving the medial pre-frontal cortex and hippocampus and increased microglial activation. Animals on PLX5622 diet exhibited no radiation-induced cognitive deficits, and expression of resting and activated microglia were almost completely abolished, without any effects on the oligodendrocyte progenitors, throughout the brain. While PLX5622 treatment was found to attenuate radiation-induced increases in post-synaptic density protein 95 (PSD-95) puncta and to preserve mushroom type spine densities, other morphologic features of neurons and electrophysiologic measures of intrinsic excitability were relatively unaffected. Conclusions Our data suggest that microglia play a critical role in cosmic radiation-induced cognitive deficits in mice and, that approaches targeting microglial function are poised to provide considerable benefit to the brain exposed to charged particles.
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Affiliation(s)
- Barrett D Allen
- Department of Radiation Oncology, University of California, Irvine, CA, USA
| | - Amber R Syage
- Department of Radiation Oncology, University of California, Irvine, CA, USA
| | - Mattia Maroso
- Department of Neurosurgery, Stanford University, Stanford, CA, USA
| | - Al Anoud D Baddour
- Department of Radiation Oncology, University of California, Irvine, CA, USA
| | - Valerie Luong
- Department of Radiation Oncology, University of California, Irvine, CA, USA
| | - Harutyun Minasyan
- Department of Radiation Oncology, University of California, Irvine, CA, USA
| | - Erich Giedzinski
- Department of Radiation Oncology, University of California, Irvine, CA, USA
| | | | - Ivan Soltesz
- Department of Neurosurgery, Stanford University, Stanford, CA, USA
| | - Charles L Limoli
- Department of Radiation Oncology, University of California, Irvine, CA, USA
| | - Janet E Baulch
- Department of Radiation Oncology, University of California, Irvine, CA, USA
| | - Munjal M Acharya
- Department of Radiation Oncology, University of California, Irvine, CA, USA.
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20
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Britten RA, Duncan VD, Fesshaye A, Rudobeck E, Nelson GA, Vlkolinsky R. Altered Cognitive Flexibility and Synaptic Plasticity in the Rat Prefrontal Cortex after Exposure to Low (≤15 cGy) Doses of 28Si Radiation. Radiat Res 2020; 193:223-235. [DOI: 10.1667/rr15458.1] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
| | | | | | - Emil Rudobeck
- Department of Basic Sciences, Loma Linda University, Loma Linda, California, 92354
| | - Gregory A. Nelson
- Department of Basic Sciences, Loma Linda University, Loma Linda, California, 92354
| | - Roman Vlkolinsky
- Department of Basic Sciences, Loma Linda University, Loma Linda, California, 92354
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21
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Poletaeva II, Perepelkina OV, Ogienko NA, Tarassova AY, Lilp IG, Koshlan IV, Pavlova GV, Revishchin AV. Influence of Proton Irradiation on Solution of the Cognitive Puzzle-Box Test in Mice and Adult Neurogenesis. BIOL BULL+ 2019. [DOI: 10.1134/s1062359019120069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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22
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Severyukhin YS, Feldman TB, Ostrovsky MA, Molokanov AG. Effects of Cranial Exposure to 170-MeV Proton Radiation at a Dose of 5 Gy on the Visual Behavior and Optomotor Response of Adults Rats. BIOL BULL+ 2019. [DOI: 10.1134/s1062359019120070] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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23
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Kiffer F, Boerma M, Allen A. Behavioral effects of space radiation: A comprehensive review of animal studies. LIFE SCIENCES IN SPACE RESEARCH 2019; 21:1-21. [PMID: 31101151 PMCID: PMC7150604 DOI: 10.1016/j.lssr.2019.02.004] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Revised: 02/14/2019] [Accepted: 02/17/2019] [Indexed: 05/04/2023]
Abstract
As NASA prepares for the first manned mission to Mars in the next 20 years, close attention has been placed on the cognitive welfare of astronauts, who will likely endure extended durations in confinement and microgravity and be subjected to the radioactive charged particles travelling at relativistic speeds in interplanetary space. The future of long-duration manned spaceflight, thus, depends on understanding the individual hazards associated with the environment beyond Earth's protective magnetosphere. Ground-based single-particle studies of exposed mice and rats have, in the last 30 years, overwhelmingly reported deficits in their cognitive behaviors. However, as particle-accelerator technologies at NASA's Space Radiation Laboratory continue to progress, more realistic representations of space radiation are materializing, including multiple-particle exposures and, eventually, at multiple energy distributions. These advancements help determine how to best mitigate possible hazards due to space radiation. However, risk models will depend on delineating which particles are most responsible for specific behavioral outcomes and whether multiple-particle exposures produce synergistic effects. Here, we review the literature on animal exposures by particle, energy, and behavioral assay to inform future mixed-field radiation studies of possible behavioral outcomes.
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Affiliation(s)
- Frederico Kiffer
- Division of Radiation Health, College of Pharmacy, University of Arkansas for Medical Sciences, Little Rock, AR, United States; Department of Pharmaceutical Sciences, College of Pharmacy, University of Arkansas for Medical Sciences, Little Rock, AR, United States.
| | - Marjan Boerma
- Division of Radiation Health, College of Pharmacy, University of Arkansas for Medical Sciences, Little Rock, AR, United States; Department of Pharmaceutical Sciences, College of Pharmacy, University of Arkansas for Medical Sciences, Little Rock, AR, United States.
| | - Antiño Allen
- Division of Radiation Health, College of Pharmacy, University of Arkansas for Medical Sciences, Little Rock, AR, United States; Department of Pharmaceutical Sciences, College of Pharmacy, University of Arkansas for Medical Sciences, Little Rock, AR, United States; Department of Neurobiology & Developmental Sciences, College of Medicine, University of Arkansas for Medical Sciences, Little Rock, AR, United States.
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Whole-Body 12C Irradiation Transiently Decreases Mouse Hippocampal Dentate Gyrus Proliferation and Immature Neuron Number, but Does Not Change New Neuron Survival Rate. Int J Mol Sci 2018; 19:ijms19103078. [PMID: 30304778 PMCID: PMC6213859 DOI: 10.3390/ijms19103078] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Revised: 09/17/2018] [Accepted: 09/21/2018] [Indexed: 02/08/2023] Open
Abstract
High-charge and -energy (HZE) particles comprise space radiation and they pose a challenge to astronauts on deep space missions. While exposure to most HZE particles decreases neurogenesis in the hippocampus—a brain structure important in memory—prior work suggests that 12C does not. However, much about 12C’s influence on neurogenesis remains unknown, including the time course of its impact on neurogenesis. To address this knowledge gap, male mice (9–11 weeks of age) were exposed to whole-body 12C irradiation 100 cGy (IRR; 1000 MeV/n; 8 kEV/µm) or Sham treatment. To birthdate dividing cells, mice received BrdU i.p. 22 h post-irradiation and brains were harvested 2 h (Short-Term) or three months (Long-Term) later for stereological analysis indices of dentate gyrus neurogenesis. For the Short-Term time point, IRR mice had fewer Ki67, BrdU, and doublecortin (DCX) immunoreactive (+) cells versus Sham mice, indicating decreased proliferation (Ki67, BrdU) and immature neurons (DCX). For the Long-Term time point, IRR and Sham mice had similar Ki67+ and DCX+ cell numbers, suggesting restoration of proliferation and immature neurons 3 months post-12C irradiation. IRR mice had fewer surviving BrdU+ cells versus Sham mice, suggesting decreased cell survival, but there was no difference in BrdU+ cell survival rate when compared within treatment and across time point. These data underscore the ability of neurogenesis in the mouse brain to recover from the detrimental effect of 12C exposure.
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Carr H, Alexander TC, Groves T, Kiffer F, Wang J, Price E, Boerma M, Allen AR. Early effects of 16O radiation on neuronal morphology and cognition in a murine model. LIFE SCIENCES IN SPACE RESEARCH 2018; 17:63-73. [PMID: 29753415 DOI: 10.1016/j.lssr.2018.03.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Revised: 02/23/2018] [Accepted: 03/02/2018] [Indexed: 06/08/2023]
Abstract
Astronauts exposed to high linear energy transfer radiation may experience cognitive injury. The pathogenesis of this injury is unknown but may involve glutamate receptors or modifications to dendritic structure and/or dendritic spine density and morphology. Glutamate is the major excitatory neurotransmitter in the central nervous system, where it acts on ionotropic and metabotropic glutamate receptors located at the presynaptic terminal and in the postsynaptic membrane at synapses in the hippocampus. Dendritic spines are sites of excitatory synaptic transmission, and changes in spine structure and dendrite morphology are thought to be morphological correlates of altered brain function associated with hippocampal-dependent learning and memory. The aim of the current study is to assess whether behavior, glutamate receptor gene expression, and dendritic structure in the hippocampus are altered in mice after early exposure to 16O radiation in mice. Two weeks post-irradiation, animals were tested for hippocampus-dependent cognitive performance in the Y-maze. During Y-maze testing, mice exposed to 0.1 Gy and 0.25 Gy radiation failed to distinguish the novel arm, spending approximately the same amount of time in all 3 arms during the retention trial. Exposure to 16O significantly reduced the expression of Nr1 and GluR1 in the hippocampus and modulated spine morphology in the dentate gyrus and cornu Ammon 1 within the hippocampus. The present data provide evidence that 16O radiation has early deleterious effects on mature neurons that are associated with hippocampal learning and memory.
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Affiliation(s)
- Hannah Carr
- Division of Radiation Health, University of Arkansas for Medical Sciences, Little Rock, AR 72205, United States.
| | - Tyler C Alexander
- Division of Radiation Health, University of Arkansas for Medical Sciences, Little Rock, AR 72205, United States; Department of Pharmaceutical Sciences, University of Arkansas for Medical Sciences, Little Rock, AR 72205, United States.
| | - Thomas Groves
- Division of Radiation Health, University of Arkansas for Medical Sciences, Little Rock, AR 72205, United States; Department of Pharmaceutical Sciences, University of Arkansas for Medical Sciences, Little Rock, AR 72205, United States; Neurobiology & Developmental Sciences, University of Arkansas for Medical Sciences, Little Rock, AR 72205, United States.
| | - Frederico Kiffer
- Division of Radiation Health, University of Arkansas for Medical Sciences, Little Rock, AR 72205, United States; Department of Pharmaceutical Sciences, University of Arkansas for Medical Sciences, Little Rock, AR 72205, United States.
| | - Jing Wang
- Division of Radiation Health, University of Arkansas for Medical Sciences, Little Rock, AR 72205, United States; Department of Pharmaceutical Sciences, University of Arkansas for Medical Sciences, Little Rock, AR 72205, United States.
| | - Elvin Price
- Department of Pharmaceutical Sciences, University of Arkansas for Medical Sciences, Little Rock, AR 72205, United States.
| | - Marjan Boerma
- Division of Radiation Health, University of Arkansas for Medical Sciences, Little Rock, AR 72205, United States; Department of Pharmaceutical Sciences, University of Arkansas for Medical Sciences, Little Rock, AR 72205, United States.
| | - Antiño R Allen
- Division of Radiation Health, University of Arkansas for Medical Sciences, Little Rock, AR 72205, United States; Department of Pharmaceutical Sciences, University of Arkansas for Medical Sciences, Little Rock, AR 72205, United States; Neurobiology & Developmental Sciences, University of Arkansas for Medical Sciences, Little Rock, AR 72205, United States.
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26
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Kiffer F, Howe AK, Carr H, Wang J, Alexander T, Anderson JE, Groves T, Seawright JW, Sridharan V, Carter G, Boerma M, Allen AR. Late effects of 1H irradiation on hippocampal physiology. LIFE SCIENCES IN SPACE RESEARCH 2018; 17:51-62. [PMID: 29753414 PMCID: PMC7063743 DOI: 10.1016/j.lssr.2018.03.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Revised: 03/07/2018] [Accepted: 03/10/2018] [Indexed: 05/21/2023]
Abstract
NASA's Missions to Mars and beyond will expose flight crews to potentially dangerous levels of charged-particle radiation. Of all charged nuclei, 1H is the most abundant charged particle in both the galactic cosmic ray (GCR) and solar particle event (SPE) spectra. There are currently no functional spacecraft shielding materials that are able to mitigate the charged-particle radiation encountered in space. Recent studies have demonstrated cognitive injuries due to high-dose 1H exposures in rodents. Our study investigated the effects of 1H irradiation on neuronal morphology in the hippocampus of adult male mice. 6-month-old mice received whole-body exposure to 1H at 0.5 and 1 Gy (150 MeV/n; 0.35-0.55 Gy/min) at NASA's Space Radiation Laboratory in Upton, NY. At 9-months post-irradiation, we tested each animal's open-field exploratory performance. After sacrifice, we dissected the brains along the midsagittal plane, and then either fixed or dissected further and snap-froze them. Our data showed that exposure to 0.5 Gy or 1 Gy 1H significantly increased animals' anxiety behavior in open-field testing. Our micromorphometric analyses revealed significant decreases in mushroom spine density and dendrite morphology in the Dentate Gyrus, Cornu Ammonis 3 and 1 of the hippocampus, and lowered expression of synaptic markers. Our data suggest 1H radiation significantly increased exploration anxiety and modulated the dendritic spine and dendrite morphology of hippocampal neurons at a dose of 0.5 or 1 Gy.
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Affiliation(s)
- Frederico Kiffer
- Division of Radiation Health at the University of Arkansas for Medical Sciences, 4301 West Markham, Suite 441B-2, Little Rock, AR 72205, United States; Department of Pharmaceutical Sciences, University of Arkansas for Medical Sciences, Little Rock, AR 72205, United States.
| | - Alexis K Howe
- Division of Radiation Health at the University of Arkansas for Medical Sciences, 4301 West Markham, Suite 441B-2, Little Rock, AR 72205, United States; Department of Pharmaceutical Sciences, University of Arkansas for Medical Sciences, Little Rock, AR 72205, United States.
| | - Hannah Carr
- Division of Radiation Health at the University of Arkansas for Medical Sciences, 4301 West Markham, Suite 441B-2, Little Rock, AR 72205, United States; Department of Pharmaceutical Sciences, University of Arkansas for Medical Sciences, Little Rock, AR 72205, United States.
| | - Jing Wang
- Division of Radiation Health at the University of Arkansas for Medical Sciences, 4301 West Markham, Suite 441B-2, Little Rock, AR 72205, United States; Department of Pharmaceutical Sciences, University of Arkansas for Medical Sciences, Little Rock, AR 72205, United States.
| | - Tyler Alexander
- Division of Radiation Health at the University of Arkansas for Medical Sciences, 4301 West Markham, Suite 441B-2, Little Rock, AR 72205, United States; Department of Pharmaceutical Sciences, University of Arkansas for Medical Sciences, Little Rock, AR 72205, United States.
| | - Julie E Anderson
- Division of Radiation Health at the University of Arkansas for Medical Sciences, 4301 West Markham, Suite 441B-2, Little Rock, AR 72205, United States; Department of Pharmaceutical Sciences, University of Arkansas for Medical Sciences, Little Rock, AR 72205, United States.
| | - Thomas Groves
- Division of Radiation Health at the University of Arkansas for Medical Sciences, 4301 West Markham, Suite 441B-2, Little Rock, AR 72205, United States; Department of Pharmaceutical Sciences, University of Arkansas for Medical Sciences, Little Rock, AR 72205, United States; Neurobiology and Developmental Sciences, University of Arkansas for Medical Sciences, Little Rock, AR 72205, United States.
| | - John W Seawright
- Division of Radiation Health at the University of Arkansas for Medical Sciences, 4301 West Markham, Suite 441B-2, Little Rock, AR 72205, United States; Department of Pharmaceutical Sciences, University of Arkansas for Medical Sciences, Little Rock, AR 72205, United States.
| | - Vijayalakshmi Sridharan
- Division of Radiation Health at the University of Arkansas for Medical Sciences, 4301 West Markham, Suite 441B-2, Little Rock, AR 72205, United States; Department of Pharmaceutical Sciences, University of Arkansas for Medical Sciences, Little Rock, AR 72205, United States.
| | - Gwendolyn Carter
- Division of Radiation Health at the University of Arkansas for Medical Sciences, 4301 West Markham, Suite 441B-2, Little Rock, AR 72205, United States; Department of Pharmaceutical Sciences, University of Arkansas for Medical Sciences, Little Rock, AR 72205, United States.
| | - Marjan Boerma
- Division of Radiation Health at the University of Arkansas for Medical Sciences, 4301 West Markham, Suite 441B-2, Little Rock, AR 72205, United States; Department of Pharmaceutical Sciences, University of Arkansas for Medical Sciences, Little Rock, AR 72205, United States.
| | - Antiño R Allen
- Division of Radiation Health at the University of Arkansas for Medical Sciences, 4301 West Markham, Suite 441B-2, Little Rock, AR 72205, United States; Department of Pharmaceutical Sciences, University of Arkansas for Medical Sciences, Little Rock, AR 72205, United States; Neurobiology and Developmental Sciences, University of Arkansas for Medical Sciences, Little Rock, AR 72205, United States.
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Rudobeck E, Bellone JA, Szücs A, Bonnick K, Mehrotra-Carter S, Badaut J, Nelson GA, Hartman RE, Vlkolinský R. Low-dose proton radiation effects in a transgenic mouse model of Alzheimer's disease - Implications for space travel. PLoS One 2017; 12:e0186168. [PMID: 29186131 PMCID: PMC5706673 DOI: 10.1371/journal.pone.0186168] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Accepted: 09/26/2017] [Indexed: 12/13/2022] Open
Abstract
Space radiation represents a significant health risk for astronauts. Ground-based animal studies indicate that space radiation affects neuronal functions such as excitability, synaptic transmission, and plasticity, and it may accelerate the onset of Alzheimer's disease (AD). Although protons represent the main constituent in the space radiation spectrum, their effects on AD-related pathology have not been tested. We irradiated 3 month-old APP/PSEN1 transgenic (TG) and wild type (WT) mice with protons (150 MeV; 0.1-1.0 Gy; whole body) and evaluated functional and biochemical hallmarks of AD. We performed behavioral tests in the water maze (WM) before irradiation and in the WM and Barnes maze at 3 and 6 months post-irradiation to evaluate spatial learning and memory. We also performed electrophysiological recordings in vitro in hippocampal slices prepared 6 and 9 months post-irradiation to evaluate excitatory synaptic transmission and plasticity. Next, we evaluated amyloid β (Aβ) deposition in the contralateral hippocampus and adjacent cortex using immunohistochemistry. In cortical homogenates, we analyzed the levels of the presynaptic marker synaptophysin by Western blotting and measured pro-inflammatory cytokine levels (TNFα, IL-1β, IL-6, CXCL10 and CCL2) by bead-based multiplex assay. TG mice performed significantly worse than WT mice in the WM. Irradiation of TG mice did not affect their behavioral performance, but reduced the amplitudes of population spikes and inhibited paired-pulse facilitation in CA1 neurons. These electrophysiological alterations in the TG mice were qualitatively different from those observed in WT mice, in which irradiation increased excitability and synaptic efficacy. Irradiation increased Aβ deposition in the cortex of TG mice without affecting cytokine levels and increased synaptophysin expression in WT mice (but not in the TG mice). Although irradiation with protons increased Aβ deposition, the complex functional and biochemical results indicate that irradiation effects are not synergistic to AD pathology.
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Affiliation(s)
- Emil Rudobeck
- Department of Basic Sciences, School of Medicine, Loma Linda University, Loma Linda, CA, United States of America
| | - John A. Bellone
- Department of Psychology, School of Behavioral Health, Loma Linda University, Loma Linda, CA, United States of America
| | - Attila Szücs
- BioCircuits Institute, University of California San Diego, La Jolla, CA, United States of America
| | - Kristine Bonnick
- Department of Basic Sciences, School of Medicine, Loma Linda University, Loma Linda, CA, United States of America
| | - Shalini Mehrotra-Carter
- Department of Basic Sciences, School of Medicine, Loma Linda University, Loma Linda, CA, United States of America
| | - Jerome Badaut
- Department of Physiology, School of Medicine, Loma Linda University, Loma Linda, CA, United States of America
| | - Gregory A. Nelson
- Department of Basic Sciences, School of Medicine, Loma Linda University, Loma Linda, CA, United States of America
| | - Richard E. Hartman
- Department of Psychology, School of Behavioral Health, Loma Linda University, Loma Linda, CA, United States of America
| | - Roman Vlkolinský
- Department of Basic Sciences, School of Medicine, Loma Linda University, Loma Linda, CA, United States of America
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28
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Kiffer F, Carr H, Groves T, Anderson JE, Alexander T, Wang J, Seawright JW, Sridharan V, Carter G, Boerma M, Allen AR. Effects of 1H + 16O Charged Particle Irradiation on Short-Term Memory and Hippocampal Physiology in a Murine Model. Radiat Res 2017; 189:53-63. [PMID: 29136391 DOI: 10.1667/rr14843.1] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Radiation from galactic cosmic rays (GCR) poses a significant health risk for deep-space flight crews. GCR are unique in their extremely high-energy particles. With current spacecraft shielding technology, some of the predominant particles astronauts would be exposed to are 1H + 16O. Radiation has been shown to cause cognitive deficits in mice. The hippocampus plays a key role in memory and cognitive tasks; it receives information from the cortex, undergoes dendritic-dependent processing and then relays information back to the cortex. In this study, we investigated the effects of combined 1H + 16O irradiation on cognition and dendritic structures in the hippocampus of adult male mice three months postirradiation. Six-month-old male C57BL/6 mice were irradiated first with 1H (0.5 Gy, 150 MeV/n) and 1 h later with 16O (0.1 Gy, 600 MeV/n) at the NASA Space Radiation Laboratory (Upton, NY). Three months after irradiation, animals were tested for hippocampus-dependent cognitive performance using the Y-maze. Upon sacrifice, molecular and morphological assessments were performed on hippocampal tissues. During Y-maze testing, the irradiated mice failed to distinguish the novel arm, spending approximately the same amount of time in all three arms during the retention trial relative to sham-treated controls. Irradiated animals also showed changes in expression of glutamate receptor subunits and synaptic density-associated proteins. 1H + 16O radiation compromised dendritic morphology in the cornu ammonis 1 and dentate gyrus within the hippocampus. These data indicate cognitive injuries due to 1H + 16O at three months postirradiation.
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Affiliation(s)
- Frederico Kiffer
- a Division of Radiation Health.,b Department of Pharmaceutical Sciences
| | - Hannah Carr
- a Division of Radiation Health.,b Department of Pharmaceutical Sciences
| | - Thomas Groves
- a Division of Radiation Health.,b Department of Pharmaceutical Sciences.,c Center for Translational Neurobiology and Developmental Sciences, University of Arkansas for Medical Sciences, Little Rock, Arkansas 72205
| | - Julie E Anderson
- a Division of Radiation Health.,b Department of Pharmaceutical Sciences
| | - Tyler Alexander
- a Division of Radiation Health.,b Department of Pharmaceutical Sciences
| | - Jing Wang
- a Division of Radiation Health.,b Department of Pharmaceutical Sciences
| | - John W Seawright
- a Division of Radiation Health.,b Department of Pharmaceutical Sciences
| | | | - Gwendolyn Carter
- a Division of Radiation Health.,b Department of Pharmaceutical Sciences
| | - Marjan Boerma
- a Division of Radiation Health.,b Department of Pharmaceutical Sciences
| | - Antiño R Allen
- a Division of Radiation Health.,b Department of Pharmaceutical Sciences.,c Center for Translational Neurobiology and Developmental Sciences, University of Arkansas for Medical Sciences, Little Rock, Arkansas 72205
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Whoolery CW, Walker AK, Richardson DR, Lucero MJ, Reynolds RP, Beddow DH, Clark KL, Shih HY, LeBlanc JA, Cole MG, Amaral WZ, Mukherjee S, Zhang S, Ahn F, Bulin SE, DeCarolis NA, Rivera PD, Chen BPC, Yun S, Eisch AJ. Whole-Body Exposure to 28Si-Radiation Dose-Dependently Disrupts Dentate Gyrus Neurogenesis and Proliferation in the Short Term and New Neuron Survival and Contextual Fear Conditioning in the Long Term. Radiat Res 2017; 188:532-551. [PMID: 28945526 PMCID: PMC5901735 DOI: 10.1667/rr14797.1] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Astronauts traveling to Mars will be exposed to chronic low doses of galactic cosmic space radiation, which contains highly charged, high-energy (HZE) particles. 56Fe-HZE-particle exposure decreases hippocampal dentate gyrus (DG) neurogenesis and disrupts hippocampal function in young adult rodents, raising the possibility of impaired astronaut cognition and risk of mission failure. However, far less is known about how exposure to other HZE particles, such as 28Si, influences hippocampal neurogenesis and function. To compare the influence of 28Si exposure on indices of neurogenesis and hippocampal function with previous studies on 56Fe exposure, 9-week-old C57BL/6J and Nestin-GFP mice (NGFP; made and maintained for 10 or more generations on a C57BL/6J background) received whole-body 28Si-particle-radiation exposure (0, 0.2 and 1 Gy, 300 MeV/n, LET 67 KeV/μ, dose rate 1 Gy/min). For neurogenesis assessment, the NGFP mice were injected with the mitotic marker BrdU at 22 h postirradiation and brains were examined for indices of hippocampal proliferation and neurogenesis, including Ki67+, BrdU+, BrdU+NeuN+ and DCX+ cell numbers at short- and long-term time points (24 h and 3 months postirradiation, respectively). In the short-term group, stereology revealed fewer Ki67+, BrdU+ and DCX+ cells in 1-Gy-irradiated group relative to nonirradiated control mice, fewer Ki67+ and DCX+ cells in 0.2 Gy group relative to control group and fewer BrdU+ and DCX+ cells in 1 Gy group relative to 0.2 Gy group. In contrast to the clearly observed radiation-induced, dose-dependent reductions in the short-term group across all markers, only a few neurogenesis indices were changed in the long-term irradiated groups. Notably, there were fewer surviving BrdU+ cells in the 1 Gy group relative to 0- and 0.2-Gy-irradiated mice in the long-term group. When the short- and long-term groups were analyzed by sex, exposure to radiation had a similar effect on neurogenesis indices in male and female mice, although only male mice showed fewer surviving BrdU+ cells in the long-term group. Fluorescent immunolabeling and confocal phenotypic analysis revealed that most surviving BrdU+ cells in the long-term group expressed the neuronal marker NeuN, definitively confirming that exposure to 1 Gy 28Si radiation decreased the number of surviving adult-generated neurons in male mice relative to both 0- and 0.2-Gy-irradiated mice. For hippocampal function assessment, 9-week-old male C57BL/6J mice received whole-body 28Si-particle exposure and were then assessed long-term for performance on contextual and cued fear conditioning. In the context test the animals that received 0.2 Gy froze less relative to control animals, suggesting decreased hippocampal-dependent function. However, in the cued fear conditioning test, animals that received 1 Gy froze more during the pretone portion of the test, relative to controls and 0.2-Gy-irradiated mice, suggesting enhanced anxiety. Compared to previously reported studies, these data suggest that 28Si-radiation exposure damages neurogenesis, but to a lesser extent than 56Fe radiation and that low-dose 28Si exposure induces abnormalities in hippocampal function, disrupting fear memory but also inducing anxiety-like behavior. Furthermore, exposure to 28Si radiation decreased new neuron survival in long-term male groups but not females suggests that sex may be an important factor when performing brain health risk assessment for astronauts traveling in space.
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Affiliation(s)
- Cody W. Whoolery
- Department of Psychiatry, UT Southwestern Medical Center, Dallas, Texas
| | - Angela K. Walker
- Department of Psychiatry, UT Southwestern Medical Center, Dallas, Texas
| | | | - Melanie J. Lucero
- Department of Psychiatry, UT Southwestern Medical Center, Dallas, Texas
| | - Ryan P. Reynolds
- Department of Psychiatry, UT Southwestern Medical Center, Dallas, Texas
- Mahoney Institute for Neurosciences, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
- Department of Anesthesiology and Critical Care Medicine, Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - David H. Beddow
- Department of Psychiatry, UT Southwestern Medical Center, Dallas, Texas
| | - K. Lyles Clark
- Mahoney Institute for Neurosciences, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Hung-Ying Shih
- Department of Radiation Oncology, UT Southwestern Medical Center, Dallas, Texas
| | - Junie A. LeBlanc
- Department of Psychiatry, UT Southwestern Medical Center, Dallas, Texas
| | - Mara G. Cole
- Department of Psychiatry, UT Southwestern Medical Center, Dallas, Texas
| | | | - Shibani Mukherjee
- Department of Psychiatry, UT Southwestern Medical Center, Dallas, Texas
| | - Shichuan Zhang
- Department of Radiation Oncology, UT Southwestern Medical Center, Dallas, Texas
| | - Francisca Ahn
- Department of Radiation Oncology, UT Southwestern Medical Center, Dallas, Texas
| | - Sarah E. Bulin
- Department of Psychiatry, UT Southwestern Medical Center, Dallas, Texas
| | | | - Phillip D. Rivera
- Department of Psychiatry, UT Southwestern Medical Center, Dallas, Texas
| | - Benjamin P. C. Chen
- Department of Radiation Oncology, UT Southwestern Medical Center, Dallas, Texas
| | - Sanghee Yun
- Mahoney Institute for Neurosciences, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
- Department of Anesthesiology and Critical Care Medicine, Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Amelia J. Eisch
- Department of Psychiatry, UT Southwestern Medical Center, Dallas, Texas
- Mahoney Institute for Neurosciences, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
- Department of Anesthesiology and Critical Care Medicine, Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania
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30
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Risk of defeats in the central nervous system during deep space missions. Neurosci Biobehav Rev 2016; 71:621-632. [DOI: 10.1016/j.neubiorev.2016.10.006] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2016] [Revised: 10/06/2016] [Accepted: 10/11/2016] [Indexed: 02/04/2023]
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Lee SH, Dudok B, Parihar VK, Jung KM, Zöldi M, Kang YJ, Maroso M, Alexander AL, Nelson GA, Piomelli D, Katona I, Limoli CL, Soltesz I. Neurophysiology of space travel: energetic solar particles cause cell type-specific plasticity of neurotransmission. Brain Struct Funct 2016; 222:2345-2357. [PMID: 27905022 PMCID: PMC5504243 DOI: 10.1007/s00429-016-1345-3] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2016] [Accepted: 11/25/2016] [Indexed: 12/03/2022]
Abstract
In the not too distant future, humankind will embark on one of its greatest adventures, the travel to distant planets. However, deep space travel is associated with an inevitable exposure to radiation fields. Space-relevant doses of protons elicit persistent disruptions in cognition and neuronal structure. However, whether space-relevant irradiation alters neurotransmission is unknown. Within the hippocampus, a brain region crucial for cognition, perisomatic inhibitory control of pyramidal cells (PCs) is supplied by two distinct cell types, the cannabinoid type 1 receptor (CB1)-expressing basket cells (CB1BCs) and parvalbumin (PV)-expressing interneurons (PVINs). Mice subjected to low-dose proton irradiation were analyzed using electrophysiological, biochemical and imaging techniques months after exposure. In irradiated mice, GABA release from CB1BCs onto PCs was dramatically increased. This effect was abolished by CB1 blockade, indicating that irradiation decreased CB1-dependent tonic inhibition of GABA release. These alterations in GABA release were accompanied by decreased levels of the major CB1 ligand 2-arachidonoylglycerol. In contrast, GABA release from PVINs was unchanged, and the excitatory connectivity from PCs to the interneurons also underwent cell type-specific alterations. These results demonstrate that energetic charged particles at space-relevant low doses elicit surprisingly selective long-term plasticity of synaptic microcircuits in the hippocampus. The magnitude and persistent nature of these alterations in synaptic function are consistent with the observed perturbations in cognitive performance after irradiation, while the high specificity of these changes indicates that it may be possible to develop targeted therapeutic interventions to decrease the risk of adverse events during interplanetary travel.
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Affiliation(s)
- Sang-Hun Lee
- Department of Anatomy and Neurobiology, University of California, Irvine, CA, 92697, USA. .,Department of Neurology, University of Arkansas for Medical Sciences, Little Rock, AR, 72205, USA.
| | - Barna Dudok
- Momentum Laboratory of Molecular Neurobiology, Institute of Experimental Medicine, Hungarian Academy of Sciences, 1083, Budapest, Hungary.,School of Ph.D. Studies, Semmelweis University, Budapest, Hungary
| | - Vipan K Parihar
- Department of Radiation Oncology, University of California, Irvine, CA, 92697, USA
| | - Kwang-Mook Jung
- Department of Anatomy and Neurobiology, University of California, Irvine, CA, 92697, USA
| | - Miklós Zöldi
- Momentum Laboratory of Molecular Neurobiology, Institute of Experimental Medicine, Hungarian Academy of Sciences, 1083, Budapest, Hungary.,School of Ph.D. Studies, Semmelweis University, Budapest, Hungary
| | - Young-Jin Kang
- Department of Neurology, University of Arkansas for Medical Sciences, Little Rock, AR, 72205, USA
| | - Mattia Maroso
- Department of Anatomy and Neurobiology, University of California, Irvine, CA, 92697, USA.,Department of Neurosurgery, and Neurology and Neurological Sciences, Stanford University, Palo Alto, CA, 94305, USA
| | - Allyson L Alexander
- Department of Neurosurgery, and Neurology and Neurological Sciences, Stanford University, Palo Alto, CA, 94305, USA
| | - Gregory A Nelson
- Division of Radiation Research, Department of Basic Sciences, Loma Linda University, Loma Linda, CA, 92350, USA
| | - Daniele Piomelli
- Department of Anatomy and Neurobiology, University of California, Irvine, CA, 92697, USA
| | - István Katona
- Momentum Laboratory of Molecular Neurobiology, Institute of Experimental Medicine, Hungarian Academy of Sciences, 1083, Budapest, Hungary
| | - Charles L Limoli
- Department of Radiation Oncology, University of California, Irvine, CA, 92697, USA
| | - Ivan Soltesz
- Department of Neurosurgery, and Neurology and Neurological Sciences, Stanford University, Palo Alto, CA, 94305, USA
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32
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Kokhan VS, Matveeva MI, Bazyan AS, Kudrin VS, Mukhametov A, Shtemberg AS. Combined effects of antiorthostatic suspension and ionizing radiation on the behaviour and neurotransmitters changes in different brain structures of rats. Behav Brain Res 2016; 320:473-483. [PMID: 27776994 DOI: 10.1016/j.bbr.2016.10.032] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Revised: 10/16/2016] [Accepted: 10/20/2016] [Indexed: 11/29/2022]
Abstract
Space flight factors (SFF) significantly affect the operating activity of astronauts during deep space missions. In contrast to an orbital flight, leaving the Earth's magnetic field is fraught with the dangers of exposure to ionizing radiation and more specifically, the high-energy nuclei component of galactic cosmic rays. Microgravity, just another critical non-radiation factor, significantly affects the normal functioning of the CNS. Some morphological structures of the brain, such as the prefrontal cortex and the hippocampus, that are rich in monoaminergic and acetylcholinergic neurones, are the most sensitive to the effects of ionizing radiation and non-radiation spaceflight factors (SFF). In this work we have studied the combined effects of microgravity (in antiorthostatic suspension model, AS) and irradiation (γ-ray and protons in spread-out Bragg peak) on the behaviour, cognitive abilities, and metabolism of monoamines and acetylcholine in the key structures of the rat's brain. Irradiation (as independently as combined with AS) resulted in the decrease of thigmotaxis in rats. Learning problems, caused by the malfunctioning of the working memory but not the spatial memory, were observed in response to AS as well as to the SFF in combination. Analysis of monoamines metabolism showed that the serotoninergic system was the most affected by the SFF. Concentration of acetylcholine in the hippocampus significantly increased in the groups of irradiated rats, and in the groups which were exposed to the SFF in combination, compared to the rats exposed only to AS.
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Affiliation(s)
- V S Kokhan
- Laboratory of Extreme Physiology, Institute of Medico-Biological Problems RAS, Moscow, Russia.
| | - M I Matveeva
- Laboratory of Extreme Physiology, Institute of Medico-Biological Problems RAS, Moscow, Russia
| | - A S Bazyan
- Institute of Higher Nervous Activity and Neurophysiology RAS, Moscow, Russia
| | - V S Kudrin
- Zakusov Institute of Pharmacology RAMS, Moscow, Russia
| | - A Mukhametov
- Institute of Physiologically Active Compounds RAS, Chernogolovka, Russia
| | - A S Shtemberg
- Laboratory of Extreme Physiology, Institute of Medico-Biological Problems RAS, Moscow, Russia
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Long-term effects of simulated microgravity and/or chronic exposure to low-dose gamma radiation on behavior and blood-brain barrier integrity. NPJ Microgravity 2016; 2:16019. [PMID: 28725731 PMCID: PMC5516431 DOI: 10.1038/npjmgrav.2016.19] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2016] [Revised: 04/05/2016] [Accepted: 04/22/2016] [Indexed: 12/11/2022] Open
Abstract
Astronauts on lengthy voyages will be exposed to an environment of microgravity and ionizing radiation that may have adverse effects on physical abilities, mood, and cognitive functioning. However, little is known about the long-term effects of combined microgravity and low-dose radiation. We exposed mice to gamma radiation using a cobalt-57 plate (0.01 cGy/h for a total dose of 0.04 Gy), hindlimb unloading to simulate microgravity, or a combination of both for 3 weeks. Mice then underwent a behavioral test battery after 1 week, 1 month, 4 months, and 8 months to assess sensorimotor coordination/balance (rotarod), activity levels (open field), learned helplessness/depression-like behavior (tail suspension test), risk-taking (elevated zero maze), and spatial learning/memory (water maze). Aquaporin-4 (AQP4) expression was assessed in the brain after behavioral testing to determine blood–brain barrier (BBB) integrity. Mice that received unloading spent significantly more time in the exposed portions of the elevated zero maze, were hypoactive in the open field, and spent less time struggling on the tail suspension test than mice that did not receive unloading. Mice in the combination group expressed more AQP4 immunoactivity than controls. Elevated zero maze and AQP4 data were correlated. No differences were seen on the water maze or rotarod, and no radiation-only effects were observed. These results suggest that microgravity may lead to changes in exploratory/risk-taking behaviors in the absence of other sensorimotor or cognitive deficits and that combined microgravity and a chronic, low dose of gamma radiation may lead to BBB dysfunction.
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Cacao E, Cucinotta FA. Modeling Impaired Hippocampal Neurogenesis after Radiation Exposure. Radiat Res 2016; 185:319-31. [DOI: 10.1667/rr14289.s1] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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