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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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Raber J, Holden S, Kessler K, Glaeser B, McQuesten C, Chaudhari M, Stenzel F, Lenarczyk M, Leonard SW, Morré J, Choi J, Kronenberg A, Borg A, Kwok A, Stevens JF, Olsen C, Willey JS, Bobe G, Minnier J, Baker JE. Effects of photon irradiation in the presence and absence of hindlimb unloading on the behavioral performance and metabolic pathways in the plasma of Fischer rats. Front Physiol 2024; 14:1316186. [PMID: 38260101 PMCID: PMC10800373 DOI: 10.3389/fphys.2023.1316186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Accepted: 12/11/2023] [Indexed: 01/24/2024] Open
Abstract
Introduction: The space environment astronauts experience during space missions consists of multiple environmental challenges, including microgravity. In this study, we assessed the behavioral and cognitive performances of male Fisher rats 2 months after sham irradiation or total body irradiation with photons in the absence or presence of simulated microgravity. We analyzed the plasma collected 9 months after sham irradiation or total body irradiation for distinct alterations in metabolic pathways and to determine whether changes to metabolic measures were associated with specific behavioral and cognitive measures. Methods: A total of 344 male Fischer rats were irradiated with photons (6 MeV; 3, 8, or 10 Gy) in the absence or presence of simulated weightlessness achieved using hindlimb unloading (HU). To identify potential plasma biomarkers of photon radiation exposure or the HU condition for behavioral or cognitive performance, we performed regression analyses. Results: The behavioral effects of HU on activity levels in an open field, measures of anxiety in an elevated plus maze, and anhedonia in the M&M consumption test were more pronounced than those of photon irradiation. Phenylalanine, tyrosine, and tryptophan metabolism, and phenylalanine metabolism and biosynthesis showed very strong pathway changes, following photon irradiation and HU in animals irradiated with 3 Gy. Here, 29 out of 101 plasma metabolites were associated with 1 out of 13 behavioral measures. In the absence of HU, 22 metabolites were related to behavioral and cognitive measures. In HU animals that were sham-irradiated or irradiated with 8 Gy, one metabolite was related to behavioral and cognitive measures. In HU animals irradiated with 3 Gy, six metabolites were related to behavioral and cognitive measures. Discussion: These data suggest that it will be possible to develop stable plasma biomarkers of behavioral and cognitive performance, following environmental challenges like HU and radiation exposure.
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Affiliation(s)
- Jacob Raber
- Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, OR, United States
- Departments of Neurology, and Radiation Medicine, Division of Neuroscience ONPRC, Oregon Health & Science University, Portland, OR, United States
- College of Pharmacy, Oregon State University, Corvallis, OR, United States
| | - Sarah Holden
- Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, OR, United States
| | - Kat Kessler
- Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, OR, United States
| | - Breanna Glaeser
- Neuroscience Center and Department of Pharmacology and Toxicology, Medical College of Wisconsin, Milwaukee, WI, United States
| | - Chloe McQuesten
- Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, OR, United States
| | - Mitali Chaudhari
- Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, OR, United States
| | - Fiona Stenzel
- Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, OR, United States
| | - Marek Lenarczyk
- Radiation Biosciences Laboratory, Medical College of Wisconsin, Milwaukee, WI, United States
| | - Scott Willem Leonard
- Department of Radiation Oncology, Wake Forest School of Medicine, Winston-Salem, NC, United States
| | - Jeffrey Morré
- Mass Spectrometry Core, Oregon State University, Corvallis, OR, United States
| | - Jaewoo Choi
- Linus Pauling Institute, Oregon State University, Corvallis, OR, United States
| | - Amy Kronenberg
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA, United States
| | - Alexander Borg
- Department of Radiation Oncology, Wake Forest School of Medicine, Winston-Salem, NC, United States
| | - Andy Kwok
- Department of Radiation Oncology, Wake Forest School of Medicine, Winston-Salem, NC, United States
| | - Jan Frederik Stevens
- College of Pharmacy, Oregon State University, Corvallis, OR, United States
- Linus Pauling Institute, Oregon State University, Corvallis, OR, United States
| | - Christopher Olsen
- Neuroscience Center and Department of Pharmacology and Toxicology, Medical College of Wisconsin, Milwaukee, WI, United States
| | - Jeffrey S. Willey
- Department of Radiation Oncology, Wake Forest School of Medicine, Winston-Salem, NC, United States
| | - Gerd Bobe
- Linus Pauling Institute, Oregon State University, Corvallis, OR, United States
- Department of Animal Sciences, Oregon State University, Corvallis, OR, United States
| | - Jessica Minnier
- Oregon Health & Science University-Portland State University School of Public Health, Knight Cancer Institute Biostatistics Shared Resource, The Knight Cardiovascular Institute, OR Health & Science University, Portland, OR, United States
| | - John E. Baker
- Neuroscience Center and Department of Pharmacology and Toxicology, Medical College of Wisconsin, Milwaukee, WI, United States
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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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Rabin BM, Miller MG, Shukitt-Hale B. Effects of preexposure to a subthreshold dose of helium particles on the changes in performance produced by exposure to helium particles. LIFE SCIENCES IN SPACE RESEARCH 2023; 37:88-96. [PMID: 37087183 DOI: 10.1016/j.lssr.2023.03.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Revised: 03/01/2023] [Accepted: 03/15/2023] [Indexed: 05/03/2023]
Abstract
On exploratory class missions, such as a mission to Mars, astronauts will be exposed to doses of particles of high energy and charge and protons up to 30 - 40 cGy. These exposures will most likely occur at random intervals across the estimated 3-yr duration of the mission. As such, the possibility of an interaction between particles must be taken into account: a prior subthreshold exposure to one particle may prevent or minimize the effect of a subsequent exposure (adaptation), or there may be an additive effect such that the prior exposure may sensitize the individual to a subsequent exposure of the same or different radiations. Two identical replications were run in which rats were exposed to a below threshold dose of 4He particles and 2, 24 or 72 h later given either a second below threshold or an above threshold dose of 4He particles and tested for performance on an operant task. The results indicate that preexposure to a subthreshold dose of 4He particles can either sensitize or attenuate the effects of the subsequent dose, depending upon the interval between exposures and the doses. These results suggest that exposure to multiple doses of heavy particles may have implications for astronaut health on exploratory class missions.
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Affiliation(s)
- Bernard M Rabin
- Department of Psychology, UMBC, Baltimore, MD 21250, United States of America.
| | - Marshall G Miller
- Duke Molecular Physiology Institute and Center for the Study of Aging and Human Development, Duke Univ., Durham, NC 27710, United States of America
| | - Barbara Shukitt-Hale
- Human Nutrition Research Center on Aging, USDA, Tufts Univ., Boston, MA 02111, United States of America
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5
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The Effects of Galactic Cosmic Rays on the Central Nervous System: From Negative to Unexpectedly Positive Effects That Astronauts May Encounter. BIOLOGY 2023; 12:biology12030400. [PMID: 36979092 PMCID: PMC10044754 DOI: 10.3390/biology12030400] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2023] [Revised: 02/23/2023] [Accepted: 02/25/2023] [Indexed: 03/06/2023]
Abstract
Galactic cosmic rays (GCR) pose a serious threat to astronauts’ health during deep space missions. The possible functional alterations of the central nervous system (CNS) under GCR exposure can be critical for mission success. Despite the obvious negative effects of ionizing radiation, a number of neutral or even positive effects of GCR irradiation on CNS functions were revealed in ground-based experiments with rodents and primates. This review is focused on the GCR exposure effects on emotional state and cognition, emphasizing positive effects and their potential mechanisms. We integrate these data with GCR effects on adult neurogenesis and pathological protein aggregation, forming a complete picture. We conclude that GCR exposure causes multidirectional effects on cognition, which may be associated with emotional state alterations. However, the irradiation in space-related doses either has no effect or has performance enhancing effects in solving high-level cognition tasks and tasks with a high level of motivation. We suppose the model of neurotransmission changes after irradiation, although the molecular mechanisms of this phenomenon are not fully understood.
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6
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Hirayama J, Hattori A, Takahashi A, Furusawa Y, Tabuchi Y, Shibata M, Nagamatsu A, Yano S, Maruyama Y, Matsubara H, Sekiguchi T, Suzuki N. Physiological consequences of space flight, including abnormal bone metabolism, space radiation injury, and circadian clock dysregulation: Implications of melatonin use and regulation as a countermeasure. J Pineal Res 2023; 74:e12834. [PMID: 36203395 DOI: 10.1111/jpi.12834] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 10/03/2022] [Accepted: 10/04/2022] [Indexed: 12/15/2022]
Abstract
Exposure to the space environment induces a number of pathophysiological outcomes in astronauts, including bone demineralization, sleep disorders, circadian clock dysregulation, cardiovascular and metabolic dysfunction, and reduced immune system function. A recent report describing experiments aboard the Space Shuttle mission, STS-132, showed that the level of melatonin, a hormone that provides the biochemical signal of darkness, was decreased during microgravity in an in vitro culture model. Additionally, abnormal lighting conditions in outer space, such as low light intensity in orbital spacecraft and the altered 24-h light-dark cycles, may result in the dysregulation of melatonin rhythms and the misalignment of the circadian clock from sleep and work schedules in astronauts. Studies on Earth have demonstrated that melatonin regulates various physiological functions including bone metabolism. These data suggest that the abnormal regulation of melatonin in outer space may contribute to pathophysiological conditions of astronauts. In addition, experiments with high-linear energy transfer radiation, a ground-based model of space radiation, showed that melatonin may serve as a protectant against space radiation. Gene expression profiling using an in vitro culture model exposed to space flight during the STS-132 mission, showed that space radiation alters the expression of DNA repair and oxidative stress response genes, indicating that melatonin counteracts the expression of these genes responsive to space radiation to promote cell survival. These findings implicate the use of exogenous melatonin and the regulation of endogenous melatonin as countermeasures for the physiological consequences of space flight.
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Affiliation(s)
- Jun Hirayama
- Department of Clinical Engineering, Faculty of Health Sciences & Division of Health Sciences, Graduate School of Sustainable Systems Science, Komatsu University, Komatsu, Japan
| | - Atsuhiko Hattori
- Department of Biology, College of Liberal Arts and Sciences, Tokyo Medical and Dental University, Ichikawa, Japan
| | | | - Yukihiro Furusawa
- Department of Pharmaceutical Engineering, Faculty of Engineering, Toyama Prefectural University, Toyama, Japan
| | - Yoshiaki Tabuchi
- Life Science Research Center, University of Toyama, Toyama, Japan
| | - Masahiro Shibata
- Department of Biology, College of Liberal Arts and Sciences, Tokyo Medical and Dental University, Ichikawa, Japan
| | | | - Sachiko Yano
- Japan Aerospace Exploration Agency, Tsukuba, Japan
| | - Yusuke Maruyama
- Department of Biology, College of Liberal Arts and Sciences, Tokyo Medical and Dental University, Ichikawa, Japan
| | - Hajime Matsubara
- Noto Center for Fisheries Science and Technology, Kanazawa University, Noto-cho, Ishikawa, Japan
| | - Toshio Sekiguchi
- Noto Marine Laboratory, Institute of Nature and Environmental Technology, Kanazawa University, Noto-cho, Japan
| | - Nobuo Suzuki
- Noto Marine Laboratory, Institute of Nature and Environmental Technology, Kanazawa University, Noto-cho, Japan
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7
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Moulder JE, Cohen EP, Medhora M, Fish BL. Angiotensin converting enzyme (ACE) inhibitors as radiation countermeasures for long-duration space flights. LIFE SCIENCES IN SPACE RESEARCH 2022; 35:60-68. [PMID: 36336371 DOI: 10.1016/j.lssr.2022.04.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Revised: 04/19/2022] [Accepted: 04/20/2022] [Indexed: 06/16/2023]
Abstract
Angiotensin converting enzyme (ACE) inhibitors are effective countermeasures to chronic radiation injuries in rodent models, and there is evidence for similar effects in humans. In rodent models ACE inhibitors are effective mitigators of radiation injury to kidney, lung, central nervous system (CNS) and skin, even when started weeks after irradiation. In humans, the best data for their efficacy as radiation countermeasures comes from retrospective studies of injuries in radiotherapy patients. We propose that ACE inhibitors, at doses approved for human use for other indications, could be used to reduce the risk of chronic radiation injuries from deep-space exploration. Because of the potential interaction of ACE inhibitors and microgravity (due to effects of ACE inhibitors on fluid balance) use might be restricted to post-exposure when/if radiation exposures reached a danger level. A major unresolved issue for this approach is the sparse evidence for the efficacy of ACE inhibitors after low-dose-rate exposure and/or for high-LET radiations (as would occur on long-duration space flights). A second issue is that the lack of a clear mechanism of action of the ACE inhibitors as mitigators makes obtaining an appropriate label under the Food and Drug Administration Animal Rule difficult.
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Affiliation(s)
- John E Moulder
- Radiation Oncology, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226 United States
| | - Eric P Cohen
- Nephrology, New York University School of Medicine, 550 First Ave, New York, NY 10016 United States.
| | - Meetha Medhora
- Radiation Oncology, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226 United States
| | - Brian L Fish
- Radiation Oncology, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226 United States
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8
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McNerlin C, Guan F, Bronk L, Lei K, Grosshans D, Young DW, Gaber MW, Maletic-Savatic M. Targeting hippocampal neurogenesis to protect astronauts' cognition and mood from decline due to space radiation effects. LIFE SCIENCES IN SPACE RESEARCH 2022; 35:170-179. [PMID: 36336363 DOI: 10.1016/j.lssr.2022.07.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Revised: 06/30/2022] [Accepted: 07/26/2022] [Indexed: 06/16/2023]
Abstract
Neurogenesis is an essential, lifelong process during which neural stem cells generate new neurons within the hippocampus, a center for learning, memory, and mood control. Neural stem cells are vulnerable to environmental insults spanning from chronic stress to radiation. These insults reduce their numbers and diminish neurogenesis, leading to memory decline, anxiety, and depression. Preserving neural stem cells could thus help prevent these neurogenesis-associated pathologies, an outcome particularly important for long-term space missions where environmental exposure to radiation is significantly higher than on Earth. Multiple developments, from mechanistic discoveries of radiation injury on hippocampal neurogenesis to new platforms for the development of selective, specific, effective, and safe small molecules as neurogenesis-protective agents hold great promise to minimize radiation damage on neurogenesis. In this review, we summarize the effects of space-like radiation on hippocampal neurogenesis. We then focus on current advances in drug discovery and development and discuss the nuclear receptor TLX/NR2E1 (oleic acid receptor) as an example of a neurogenic target that might rescue neurogenesis following radiation.
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Affiliation(s)
- Clare McNerlin
- Georgetown University School of Medicine, 3900 Reservoir Rd NW, Washington D.C. 20007, United States of America
| | - Fada Guan
- Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, CT, 06510, United States of America
| | - Lawrence Bronk
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, TX 77030, United States of America
| | - Kevin Lei
- Graduate School for Biomedical Sciences, Baylor College of Medicine, Houston, Texas, 77030, United States of America; Jan and Dan Duncan Neurological Research Institute, 1250 Moursund St. Houston, TX 77030, United States of America
| | - David Grosshans
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, TX 77030, United States of America
| | - Damian W Young
- Jan and Dan Duncan Neurological Research Institute, 1250 Moursund St. Houston, TX 77030, United States of America; Center for Drug Discovery, Department of Pathology and Immunology Baylor College of Medicine, Houston, Texas, 77030, United States of America; Department of Pharmacology and Chemical Biology, Baylor College of Medicine, Houston, Texas 77030, United States of America
| | - M Waleed Gaber
- Department of Pediatrics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, United States of America.
| | - Mirjana Maletic-Savatic
- Jan and Dan Duncan Neurological Research Institute, 1250 Moursund St. Houston, TX 77030, United States of America; Department of Pediatrics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, United States of America; Department of Neuroscience, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, United States of America.
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9
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Miller KB, Mi KL, Nelson GA, Norman RB, Patel ZS, Huff JL. Ionizing radiation, cerebrovascular disease, and consequent dementia: A review and proposed framework relevant to space radiation exposure. Front Physiol 2022; 13:1008640. [PMID: 36388106 PMCID: PMC9640983 DOI: 10.3389/fphys.2022.1008640] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Accepted: 09/29/2022] [Indexed: 09/05/2023] Open
Abstract
Space exploration requires the characterization and management or mitigation of a variety of human health risks. Exposure to space radiation is one of the main health concerns because it has the potential to increase the risk of cancer, cardiovascular disease, and both acute and late neurodegeneration. Space radiation-induced decrements to the vascular system may impact the risk for cerebrovascular disease and consequent dementia. These risks may be independent or synergistic with direct damage to central nervous system tissues. The purpose of this work is to review epidemiological and experimental data regarding the impact of low-to-moderate dose ionizing radiation on the central nervous system and the cerebrovascular system. A proposed framework outlines how space radiation-induced effects on the vasculature may increase risk for both cerebrovascular dysfunction and neural and cognitive adverse outcomes. The results of this work suggest that there are multiple processes by which ionizing radiation exposure may impact cerebrovascular function including increases in oxidative stress, neuroinflammation, endothelial cell dysfunction, arterial stiffening, atherosclerosis, and cerebral amyloid angiopathy. Cerebrovascular adverse outcomes may also promote neural and cognitive adverse outcomes. However, there are many gaps in both the human and preclinical evidence base regarding the long-term impact of ionizing radiation exposure on brain health due to heterogeneity in both exposures and outcomes. The unique composition of the space radiation environment makes the translation of the evidence base from terrestrial exposures to space exposures difficult. Additional investigation and understanding of the impact of low-to-moderate doses of ionizing radiation including high (H) atomic number (Z) and energy (E) (HZE) ions on the cerebrovascular system is needed. Furthermore, investigation of how decrements in vascular systems may contribute to development of neurodegenerative diseases in independent or synergistic pathways is important for protecting the long-term health of astronauts.
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Affiliation(s)
| | | | - Gregory A. Nelson
- Department of Basic Sciences, Division of Biomedical Engineering Sciences, Loma Linda University, Loma Linda, CA, United States
- NASA Johnson Space Center, Houston, TX, United States
- KBR Inc., Houston, TX, United States
| | - Ryan B. Norman
- NASA Langley Research Center, Hampton, VA, United States
| | - Zarana S. Patel
- NASA Johnson Space Center, Houston, TX, United States
- KBR Inc., Houston, TX, United States
| | - Janice L. Huff
- NASA Langley Research Center, Hampton, VA, United States
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Wu MY, Zou WJ, Yu P, Yang Y, Li SJ, Liu Q, Xie J, Chen SQ, Lin WJ, Tang Y. Cranial irradiation impairs intrinsic excitability and synaptic plasticity of hippocampal CA1 pyramidal neurons with implications for cognitive function. Neural Regen Res 2022; 17:2253-2259. [PMID: 35259846 PMCID: PMC9083168 DOI: 10.4103/1673-5374.336875] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Radiation therapy is a standard treatment for head and neck tumors. However, patients often exhibit cognitive impairments following radiation therapy. Previous studies have revealed that hippocampal dysfunction, specifically abnormal hippocampal neurogenesis or neuroinflammation, plays a key role in radiation-induced cognitive impairment. However, the long-term effects of radiation with respect to the electrophysiological adaptation of hippocampal neurons remain poorly characterized. We found that mice exhibited cognitive impairment 3 months after undergoing 10 minutes of cranial irradiation at a dose rate of 3 Gy/min. Furthermore, we observed a remarkable reduction in spike firing and excitatory synaptic input, as well as greatly enhanced inhibitory inputs, in hippocampal CA1 pyramidal neurons. Corresponding to the electrophysiological adaptation, we found reduced expression of synaptic plasticity marker VGLUT1 and increased expression of VGAT. Furthermore, in irradiated mice, long-term potentiation in the hippocampus was weakened and GluR1 expression was inhibited. These findings suggest that radiation can impair intrinsic excitability and synaptic plasticity in hippocampal CA1 pyramidal neurons.
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Affiliation(s)
- Min-Yi Wu
- Department of Neurology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong Province, China
| | - Wen-Jun Zou
- State Key Laboratory of Organ Failure Research, Key Laboratory of Mental Health of the Ministry of Education, Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Key Laboratory of Psychiatric Disorders of Guangdong Province, Collaborative Innovation Center for Brain Science, Department of Neurobiology, Southern Medical University, Guangzhou, Guangdong Province, China
| | - Pei Yu
- Department of Neurology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong Province, China
| | - Yuhua Yang
- Department of Neurology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong Province, China
| | - Shao-Jian Li
- Department of Neurology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong Province, China
| | - Qiang Liu
- Department of Neurology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong Province, China
| | - Jiatian Xie
- Department of Neurology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong Province, China
| | - Si-Qi Chen
- Department of Anesthesiology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong Province, China
| | - Wei-Jye Lin
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Guangdong-Hong Kong Joint Laboratory for RNA Medicine; Medical Research Center, Sun Yat-sen Memorial Hospital; Guangdong Province Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong Province, China
| | - Yamei Tang
- Department of Neurology, Sun Yat-sen Memorial Hospital; Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Guangdong-Hong Kong Joint Laboratory for RNA Medicine, Sun Yat-sen Memorial Hospital; Guangdong Province Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong Province, China
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11
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Simmons P, Corley C, Allen AR. Fractionated Proton Irradiation Does Not Impair Hippocampal-Dependent Short-Term or Spatial Memory in Female Mice. TOXICS 2022; 10:toxics10090507. [PMID: 36136472 PMCID: PMC9503909 DOI: 10.3390/toxics10090507] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Revised: 08/24/2022] [Accepted: 08/25/2022] [Indexed: 05/14/2023]
Abstract
The environment outside the Earth's protective magnetosphere is a much more threatening and complex space environment. The dominant causes for radiation exposure, solar particle events and galactic cosmic rays, contain high-energy protons. In space, astronauts need healthy and highly functioning cognitive abilities, of which the hippocampus plays a key role. Therefore, understanding the effects of 1H exposure on hippocampal-dependent cognition is vital for developing mitigative strategies and protective countermeasures for future missions. To investigate these effects, we subjected 6-month-old female CD1 mice to 0.75 Gy fractionated 1H (250 MeV) whole-body irradiation at the NASA Space Radiation Laboratory. The cognitive performance of the mice was tested 3 months after irradiation using Y-maze and Morris water maze tests. Both sham-irradiated and 1H-irradiated mice significantly preferred exploration of the novel arm compared to the familiar and start arms, indicating intact spatial and short-term memory. Both groups statistically spent more time in the target quadrant, indicating spatial memory retention. There were no significant differences in neurogenic and gliogenic cell counts after irradiation. In addition, proteomic analysis revealed no significant upregulation or downregulation of proteins related to behavior, neurological disease, or neural morphology. Our data suggests 1H exposure does not impair hippocampal-dependent spatial or short-term memory in female mice.
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Affiliation(s)
- Pilar Simmons
- Division of Radiation Health, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
- Department of Pharmaceutical Sciences, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
- Department of Neurobiology and Developmental Sciences, University of Arkansas for Medical Sciences, 4301 W Markham, Little Rock, AR 72205, USA
| | - Christa Corley
- Division of Radiation Health, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
- Department of Pharmaceutical Sciences, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
- Department of Neurobiology and Developmental Sciences, University of Arkansas for Medical Sciences, 4301 W Markham, Little Rock, AR 72205, USA
| | - Antiño R. Allen
- Division of Radiation Health, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
- Department of Pharmaceutical Sciences, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
- Department of Neurobiology and Developmental Sciences, University of Arkansas for Medical Sciences, 4301 W Markham, Little Rock, AR 72205, USA
- Correspondence: ; Tel.: +1-501-686-7553
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Long-Term Sex- and Genotype-Specific Effects of 56Fe Irradiation on Wild-Type and APPswe/PS1dE9 Transgenic Mice. Int J Mol Sci 2021; 22:ijms222413305. [PMID: 34948098 PMCID: PMC8703695 DOI: 10.3390/ijms222413305] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Revised: 12/07/2021] [Accepted: 12/07/2021] [Indexed: 12/22/2022] Open
Abstract
Space radiation presents a substantial threat to travel beyond Earth. Relatively low doses of high-energy particle radiation cause physiological and behavioral impairments in rodents and may pose risks to human spaceflight. There is evidence that 56Fe irradiation, a significant component of space radiation, may be more harmful to males than to females and worsen Alzheimer's disease pathology in genetically vulnerable models. Yet, research on the long-term, sex- and genotype-specific effects of 56Fe irradiation is lacking. Here, we irradiated 4-month-old male and female, wild-type and Alzheimer's-like APP/PS1 mice with 0, 0.10, or 0.50 Gy of 56Fe ions (1GeV/u). Mice underwent microPET scans before and 7.5 months after irradiation, a battery of behavioral tests at 11 months of age and were sacrificed for pathological and biochemical analyses at 12 months of age. 56Fe irradiation worsened amyloid-beta (Aβ) pathology, gliosis, neuroinflammation and spatial memory, but improved motor coordination, in male transgenic mice and worsened fear memory in wild-type males. Although sham-irradiated female APP/PS1 mice had more cerebral Aβ and gliosis than sham-irradiated male transgenics, female mice of both genotypes were relatively spared from radiation effects 8 months later. These results provide evidence for sex-specific, long-term CNS effects of space radiation.
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13
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Mhatre SD, Iyer J, Puukila S, Paul AM, Tahimic CGT, Rubinstein L, Lowe M, Alwood JS, Sowa MB, Bhattacharya S, Globus RK, Ronca AE. Neuro-consequences of the spaceflight environment. Neurosci Biobehav Rev 2021; 132:908-935. [PMID: 34767877 DOI: 10.1016/j.neubiorev.2021.09.055] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 08/03/2021] [Accepted: 09/28/2021] [Indexed: 12/17/2022]
Abstract
As human space exploration advances to establish a permanent presence beyond the Low Earth Orbit (LEO) with NASA's Artemis mission, researchers are striving to understand and address the health challenges of living and working in the spaceflight environment. Exposure to ionizing radiation, microgravity, isolation and other spaceflight hazards pose significant risks to astronauts. Determining neurobiological and neurobehavioral responses, understanding physiological responses under Central Nervous System (CNS) control, and identifying putative mechanisms to inform countermeasure development are critically important to ensuring brain and behavioral health of crew on long duration missions. Here we provide a detailed and comprehensive review of the effects of spaceflight and of ground-based spaceflight analogs, including simulated weightlessness, social isolation, and ionizing radiation on humans and animals. Further, we discuss dietary and non-dietary countermeasures including artificial gravity and antioxidants, among others. Significant future work is needed to ensure that neural, sensorimotor, cognitive and other physiological functions are maintained during extended deep space missions to avoid potentially catastrophic health and safety outcomes.
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Affiliation(s)
- Siddhita D Mhatre
- Space Biosciences Division, NASA Ames Research Center, Moffett Field, CA, 94035, USA; KBR, Houston, TX, 77002, USA; COSMIAC Research Center, University of New Mexico, Albuquerque, NM, 87131, USA
| | - Janani Iyer
- Space Biosciences Division, NASA Ames Research Center, Moffett Field, CA, 94035, USA; Universities Space Research Association, Columbia, MD, 21046, USA
| | - Stephanie Puukila
- Space Biosciences Division, NASA Ames Research Center, Moffett Field, CA, 94035, USA; Universities Space Research Association, Columbia, MD, 21046, USA; Flinders University, Adelaide, Australia
| | - Amber M Paul
- Space Biosciences Division, NASA Ames Research Center, Moffett Field, CA, 94035, USA; Universities Space Research Association, Columbia, MD, 21046, USA
| | - Candice G T Tahimic
- Space Biosciences Division, NASA Ames Research Center, Moffett Field, CA, 94035, USA; KBR, Houston, TX, 77002, USA; Department of Biology, University of North Florida, Jacksonville, FL, 32224, USA
| | - Linda Rubinstein
- Space Biosciences Division, NASA Ames Research Center, Moffett Field, CA, 94035, USA; Universities Space Research Association, Columbia, MD, 21046, USA
| | - Moniece Lowe
- Space Biosciences Division, NASA Ames Research Center, Moffett Field, CA, 94035, USA; Blue Marble Space Institute of Science, Seattle, WA, 98154, USA
| | - Joshua S Alwood
- Space Biosciences Division, NASA Ames Research Center, Moffett Field, CA, 94035, USA
| | - Marianne B Sowa
- Space Biosciences Division, NASA Ames Research Center, Moffett Field, CA, 94035, USA
| | - Sharmila Bhattacharya
- Space Biosciences Division, NASA Ames Research Center, Moffett Field, CA, 94035, USA
| | - Ruth K Globus
- Space Biosciences Division, NASA Ames Research Center, Moffett Field, CA, 94035, USA
| | - April E Ronca
- Space Biosciences Division, NASA Ames Research Center, Moffett Field, CA, 94035, USA; Wake Forest Medical School, Winston-Salem, NC, 27101, USA.
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14
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Soler I, Yun S, Reynolds RP, Whoolery CW, Tran FH, Kumar PL, Rong Y, DeSalle MJ, Gibson AD, Stowe AM, Kiffer FC, Eisch AJ. Multi-Domain Touchscreen-Based Cognitive Assessment of C57BL/6J Female Mice Shows Whole-Body Exposure to 56Fe Particle Space Radiation in Maturity Improves Discrimination Learning Yet Impairs Stimulus-Response Rule-Based Habit Learning. Front Behav Neurosci 2021; 15:722780. [PMID: 34707486 PMCID: PMC8543003 DOI: 10.3389/fnbeh.2021.722780] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Accepted: 09/08/2021] [Indexed: 12/23/2022] Open
Abstract
Astronauts during interplanetary missions will be exposed to galactic cosmic radiation, including charged particles like 56Fe. Most preclinical studies with mature, "astronaut-aged" rodents suggest space radiation diminishes performance in classical hippocampal- and prefrontal cortex-dependent tasks. However, a rodent cognitive touchscreen battery unexpectedly revealed 56Fe radiation improves the performance of C57BL/6J male mice in a hippocampal-dependent task (discrimination learning) without changing performance in a striatal-dependent task (rule-based learning). As there are conflicting results on whether the female rodent brain is preferentially injured by or resistant to charged particle exposure, and as the proportion of female vs. male astronauts is increasing, further study on how charged particles influence the touchscreen cognitive performance of female mice is warranted. We hypothesized that, similar to mature male mice, mature female C57BL/6J mice exposed to fractionated whole-body 56Fe irradiation (3 × 6.7cGy 56Fe over 5 days, 600 MeV/n) would improve performance vs. Sham conditions in touchscreen tasks relevant to hippocampal and prefrontal cortical function [e.g., location discrimination reversal (LDR) and extinction, respectively]. In LDR, 56Fe female mice more accurately discriminated two discrete conditioned stimuli relative to Sham mice, suggesting improved hippocampal function. However, 56Fe and Sham female mice acquired a new simple stimulus-response behavior and extinguished this acquired behavior at similar rates, suggesting similar prefrontal cortical function. Based on prior work on multiple memory systems, we next tested whether improved hippocampal-dependent function (discrimination learning) came at the expense of striatal stimulus-response rule-based habit learning (visuomotor conditional learning). Interestingly, 56Fe female mice took more days to reach criteria in this striatal-dependent rule-based test relative to Sham mice. Together, our data support the idea of competition between memory systems, as an 56Fe-induced decrease in striatal-based learning is associated with enhanced hippocampal-based learning. These data emphasize the power of using a touchscreen-based battery to advance our understanding of the effects of space radiation on mission critical cognitive function in females, and underscore the importance of preclinical space radiation risk studies measuring multiple cognitive processes, thereby preventing NASA's risk assessments from being based on a single cognitive domain.
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Affiliation(s)
- Ivan Soler
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Sanghee Yun
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
- Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, TX, United States
- Department of Anesthesiology and Critical Care Medicine, Children’s Hospital of Philadelphia, Philadelphia, PA, United States
| | - Ryan P. Reynolds
- Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, TX, United States
- Department of Anesthesiology and Critical Care Medicine, Children’s Hospital of Philadelphia, Philadelphia, PA, United States
| | - Cody W. Whoolery
- Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - Fionya H. Tran
- Department of Anesthesiology and Critical Care Medicine, Children’s Hospital of Philadelphia, Philadelphia, PA, United States
| | - Priya L. Kumar
- University of Pennsylvania, Philadelphia, PA, United States
| | - Yuying Rong
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Matthew J. DeSalle
- Department of Anesthesiology and Critical Care Medicine, Children’s Hospital of Philadelphia, Philadelphia, PA, United States
| | - Adam D. Gibson
- Department of Anesthesiology and Critical Care Medicine, Children’s Hospital of Philadelphia, Philadelphia, PA, United States
| | - Ann M. Stowe
- Department of Neurology and Neurological Therapeutics, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - Frederico C. Kiffer
- Department of Anesthesiology and Critical Care Medicine, Children’s Hospital of Philadelphia, Philadelphia, PA, United States
| | - Amelia J. Eisch
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
- Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, TX, United States
- Department of Anesthesiology and Critical Care Medicine, Children’s Hospital of Philadelphia, Philadelphia, PA, United States
- Department of Neuroscience, Perelman School of Medicine, Mahoney Institute for Neurosciences, University of Pennsylvania, Philadelphia, PA, United States
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15
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Life-long brain compensatory responses to galactic cosmic radiation exposure. Sci Rep 2021; 11:4292. [PMID: 33619310 PMCID: PMC7900210 DOI: 10.1038/s41598-021-83447-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Accepted: 02/01/2021] [Indexed: 12/02/2022] Open
Abstract
Galactic cosmic radiation (GCR) composed of high-energy, heavy particles (HZE) poses potentially serious hazards to long-duration crewed missions in deep space beyond earth’s magnetosphere, including planned missions to Mars. Chronic effects of GCR exposure on brain structure and cognitive function are poorly understood, thereby limiting risk reduction and mitigation strategies to protect against sequelae from exposure during and after deep-space travel. Given the selective vulnerability of the hippocampus to neurotoxic insult and the importance of this brain region to learning and memory, we hypothesized that GCR-relevant HZE exposure may induce long-term alterations in adult hippocampal neurogenesis, synaptic plasticity, and hippocampal-dependent learning and memory. To test this hypothesis, we irradiated 3-month-old male and female mice with a single, whole-body dose of 10, 50, or 100 cGy 56Fe ions (600 MeV, 181 keV/μm) at Brookhaven National Laboratory. Our data reveal complex, dynamic, time-dependent effects of HZE exposure on the hippocampus. Two months post exposure, neurogenesis, synaptic plasticity and learning were impaired compared to sham-irradiated, age-matched controls. By six months post-exposure, deficits in spatial learning were absent in irradiated mice, and synaptic potentiation was enhanced. Enhanced performance in spatial learning and facilitation of synaptic plasticity in irradiated mice persisted 12 months post-exposure, concomitant with a dramatic rebound in adult-born neurons. Synaptic plasticity and spatial learning remained enhanced 20 months post-exposure, indicating a life-long influence on plasticity and cognition from a single exposure to HZE in young adulthood. These findings suggest that GCR-exposure can persistently alter brain health and cognitive function during and after long-duration travel in deep space.
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Clark LR, Yun S, Acquah NK, Kumar PL, Metheny HE, Paixao RCC, Cohen AS, Eisch AJ. Mild Traumatic Brain Injury Induces Transient, Sequential Increases in Proliferation, Neuroblasts/Immature Neurons, and Cell Survival: A Time Course Study in the Male Mouse Dentate Gyrus. Front Neurosci 2021; 14:612749. [PMID: 33488351 PMCID: PMC7817782 DOI: 10.3389/fnins.2020.612749] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Accepted: 12/02/2020] [Indexed: 12/17/2022] Open
Abstract
Mild traumatic brain injuries (mTBIs) are prevalent worldwide. mTBIs can impair hippocampal-based functions such as memory and cause network hyperexcitability of the dentate gyrus (DG), a key entry point to hippocampal circuitry. One candidate for mediating mTBI-induced hippocampal cognitive and physiological dysfunction is injury-induced changes in the process of DG neurogenesis. There are conflicting results on how TBI impacts the process of DG neurogenesis; this is not surprising given that both the neurogenesis process and the post-injury period are dynamic, and that the quantification of neurogenesis varies widely in the literature. Even within the minority of TBI studies focusing specifically on mild injuries, there is disagreement about if and how mTBI changes the process of DG neurogenesis. Here we utilized a clinically relevant rodent model of mTBI (lateral fluid percussion injury, LFPI), gold-standard markers and quantification of the neurogenesis process, and three time points post-injury to generate a comprehensive picture of how mTBI affects adult hippocampal DG neurogenesis. Male C57BL/6J mice (6-8 weeks old) received either sham surgery or mTBI via LFPI. Proliferating cells, neuroblasts/immature neurons, and surviving cells were quantified via stereology in DG subregions (subgranular zone [SGZ], outer granule cell layer [oGCL], molecular layer, and hilus) at short-term (3 days post-injury, dpi), intermediate (7 dpi), and long-term (31 dpi) time points. The data show this model of mTBI induces transient, sequential increases in ipsilateral SGZ/GCL proliferating cells, neuroblasts/immature neurons, and surviving cells which is suggestive of mTBI-induced neurogenesis. In contrast to these ipsilateral hemisphere findings, measures in the contralateral hemisphere were not increased in key neurogenic DG subregions after LFPI. Our work in this mTBI model is in line with most literature on other and more severe models of TBI in showing TBI stimulates the process of DG neurogenesis. However, as our DG data in mTBI provide temporal, subregional, and neurogenesis-stage resolution, these data are important to consider in regard to the functional importance of TBI-induction of the neurogenesis process and future work assessing the potential of replacing and/or repairing DG neurons in the brain after TBI.
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Affiliation(s)
- Lyles R. Clark
- Department of Anesthesiology and Critical Care Medicine, The Children’s Hospital of Philadelphia (CHOP) Research Institute, Philadelphia, PA, United States
- Mahoney Institute for Neurosciences, Perelman School of Medicine, Philadelphia, PA, United States
| | - Sanghee Yun
- Department of Anesthesiology and Critical Care Medicine, The Children’s Hospital of Philadelphia (CHOP) Research Institute, Philadelphia, PA, United States
- Mahoney Institute for Neurosciences, Perelman School of Medicine, Philadelphia, PA, United States
| | - Nana K. Acquah
- Department of Anesthesiology and Critical Care Medicine, The Children’s Hospital of Philadelphia (CHOP) Research Institute, Philadelphia, PA, United States
- Biological Basis of Behavior Program, University of Pennsylvania, Philadelphia, PA, United States
| | - Priya L. Kumar
- Department of Anesthesiology and Critical Care Medicine, The Children’s Hospital of Philadelphia (CHOP) Research Institute, Philadelphia, PA, United States
- Biomechanical Engineering, University of Pennsylvania, Philadelphia, PA, United States
| | - Hannah E. Metheny
- Department of Anesthesiology and Critical Care Medicine, The Children’s Hospital of Philadelphia (CHOP) Research Institute, Philadelphia, PA, United States
| | - Rikley C. C. Paixao
- Department of Anesthesiology and Critical Care Medicine, The Children’s Hospital of Philadelphia (CHOP) Research Institute, Philadelphia, PA, United States
| | - Akivas S. Cohen
- Department of Anesthesiology and Critical Care Medicine, The Children’s Hospital of Philadelphia (CHOP) Research Institute, Philadelphia, PA, United States
- Mahoney Institute for Neurosciences, Perelman School of Medicine, Philadelphia, PA, United States
| | - Amelia J. Eisch
- Department of Anesthesiology and Critical Care Medicine, The Children’s Hospital of Philadelphia (CHOP) Research Institute, Philadelphia, PA, United States
- Mahoney Institute for Neurosciences, Perelman School of Medicine, Philadelphia, PA, United States
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17
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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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18
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Khaksarighiri S, Guo J, Wimmer-Schweingruber R, Narici L, Lohf H. Calculation of dose distribution in a realistic brain structure and the indication of space radiation influence on human brains. LIFE SCIENCES IN SPACE RESEARCH 2020; 27:33-48. [PMID: 34756228 DOI: 10.1016/j.lssr.2020.07.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Revised: 07/01/2020] [Accepted: 07/02/2020] [Indexed: 06/13/2023]
Abstract
One of the most important steps in the near-future space age will be a crew mission returning to the Moon and even a manned mission to Mars. Unfortunately, such a mission will expose astronauts to unavoidable cosmic radiation in deep space and on the Martian or lunar surface. Thus, a better understanding of the radiation environment for such a mission and the consequent biological impacts on humans, in particular the human brains, is critical. The need for this better understanding is strongly suggested by investigations on animal models and on human patients who were undergoing irradiation for cancer therapy in the head. These have revealed unexpected alterations in the central nervous system behavior and sensitivity of mature neurons in the brain to charged particles. However, such experiments shall not be carried out realistically in space using humans. Therefore, to investigate the impact of cosmic radiation on human brains and the potential influence on the brain functions, we model and study the cosmic particle-induced radiation dose in a realistic head structure. Specifically speaking, 134 slices of computed tomography (CT) images of an actual human head have been used as a 3D phantom in Geant4 (GEometry ANd Tracking), which is a Monte Carlo tool for simulating energetic particles impinging into different parts of the brain and deliver radiation dose therein. As a first step, we compare the influence of different brain structures (e.g., with or without bones, with or without soft tissues) to the resulting dose therein to demonstrate the necessity of using a realistic brain structure for our investigation. Afterward, we calculate energy-dependent functions of dose distribution, for the most important (some of the most abundant and most biologically-relevant) particle types encountered during a deep space mission inside a spacecraft or habitat such as protons, helium ions, neutrons and some major heavier ions like carbon, nitrogen, and iron particles. Furthermore, two different scenarios have been modeled as a comparison: a human head without shielding protection and a human head with an aluminum shielding shell around (of varying thickness). These functions can then be used to fold with energetic cosmic-ray particle spectra of the ambient environment for obtaining the dose rate distribution at different lobes of the human brain. Our calculation of these functions can serve as a ready tool and a baseline for further evaluations of the radiation in the brain encountered during a space mission with different radiation fields, such as on the surface of the Moon or Mars.
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Affiliation(s)
- Salman Khaksarighiri
- Institute of Experimental and Applied Physics, University of Kiel, Kiel, DE24118, Germany
| | - Jingnan Guo
- Institute of Experimental and Applied Physics, University of Kiel, Kiel, DE24118, Germany; School of Earth and Space Sciences, University of Science and Technology of China, Hefei, 230026, China; CAS Center for Excellence in Comparative Planetology, USTC, Hefei, China.
| | | | - Livio Narici
- Departments of Physics, the University of Rome 'Tor Vergata', Rome, Italy; INFN sect Tor Vergata, Rome, Italy
| | - Henning Lohf
- Institute of Experimental and Applied Physics, University of Kiel, Kiel, DE24118, Germany
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Rabin BM, Cahoon DS, Shukitt-Hale B. Response to comments by bevelacqua and mortazavi. LIFE SCIENCES IN SPACE RESEARCH 2020; 27:111-112. [PMID: 34756225 DOI: 10.1016/j.lssr.2020.09.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Accepted: 09/05/2020] [Indexed: 06/13/2023]
Affiliation(s)
| | - Danielle S Cahoon
- USDA-ARS, Human Nutrition Research Center on Aging at Tufts Univ., Boston, MA 02111
| | - Barbara Shukitt-Hale
- USDA-ARS, Human Nutrition Research Center on Aging at Tufts Univ., Boston, MA 02111
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20
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Pariset E, Malkani S, Cekanaviciute E, Costes SV. Ionizing radiation-induced risks to the central nervous system and countermeasures in cellular and rodent models. Int J Radiat Biol 2020; 97:S132-S150. [PMID: 32946305 DOI: 10.1080/09553002.2020.1820598] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
PURPOSE Harmful effects of ionizing radiation on the Central Nervous System (CNS) are a concerning outcome in the field of cancer radiotherapy and form a major risk for deep space exploration. Both acute and chronic CNS irradiation induce a complex network of molecular and cellular alterations including DNA damage, oxidative stress, cell death and systemic inflammation, leading to changes in neuronal structure and synaptic plasticity with behavioral and cognitive consequences in animal models. Due to this complexity, countermeasure or therapeutic approaches to reduce the harmful effects of ionizing radiation include a wide range of protective and mitigative strategies, which merit a thorough comparative analysis. MATERIALS AND METHODS We reviewed current approaches for developing countermeasures to both targeted and non-targeted effects of ionizing radiation on the CNS from the molecular and cellular to the behavioral level. RESULTS We focus on countermeasures that aim to mitigate the four main detrimental actions of radiation on CNS: DNA damage, free radical formation and oxidative stress, cell death, and harmful systemic responses including tissue death and neuroinflammation. We propose a comprehensive review of CNS radiation countermeasures reported for the full range of irradiation types (photons and particles, low and high linear energy transfer) and doses (from a fraction of gray to several tens of gray, fractionated and unfractionated), with a particular interest for exposure conditions relevant to deep-space environment and radiotherapy. Our review reveals the importance of combined strategies that increase DNA protection and repair, reduce free radical formation and increase their elimination, limit inflammation and improve cell viability, limit tissue damage and increase repair and plasticity. CONCLUSIONS The majority of therapeutic approaches to protect the CNS from ionizing radiation have been limited to acute high dose and high dose rate gamma irradiation, and few are translatable from animal models to potential human application due to harmful side effects and lack of blood-brain barrier permeability that precludes peripheral administration. Therefore, a promising research direction would be to focus on practical applicability and effectiveness in a wider range of irradiation paradigms, from fractionated therapeutic to deep space radiation. In addition to discovering novel therapeutics, it would be worth maximizing the benefits and reducing side effects of those that already exist. Finally, we suggest that novel cellular and tissue models for developing and testing countermeasures in the context of other impairments might also be applied to the field of CNS responses to ionizing radiation.
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Affiliation(s)
- Eloise Pariset
- Universities Space Research Association, Columbia, MD, USA.,Space Biosciences Division, NASA Ames Research Center, Moffett Field, CA, USA
| | - Sherina Malkani
- Space Biosciences Division, NASA Ames Research Center, Moffett Field, CA, USA.,Young Scientist Program, Blue Marble Space Institute of Science, Moffett Field, CA, USA
| | - Egle Cekanaviciute
- Space Biosciences Division, NASA Ames Research Center, Moffett Field, CA, USA
| | - Sylvain V Costes
- Space Biosciences Division, NASA Ames Research Center, Moffett Field, CA, USA
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21
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Suman S, Kallakury BVS, Fornace AJ, Datta K. Fractionated and Acute Proton Radiation Show Differential Intestinal Tumorigenesis and DNA Damage and Repair Pathway Response in Apc Min/+ Mice. Int J Radiat Oncol Biol Phys 2019; 105:525-536. [PMID: 31271826 DOI: 10.1016/j.ijrobp.2019.06.2532] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2019] [Revised: 05/08/2019] [Accepted: 06/24/2019] [Indexed: 11/26/2022]
Abstract
PURPOSE Proton radiation is a major component of the radiation field in outer space and is used clinically in radiation therapy of resistant cancers. Although epidemiologic studies in atom bomb survivors and radiologic workers have established radiation as a risk factor for colorectal cancer (CRC), we have yet to determine the risk of CRC posed by proton radiation owing to a lack of sufficient human or animal data. The purpose of the current study was to quantitatively and qualitatively characterize differential effects of acute and fractionated high-energy protons on colorectal carcinogenesis. METHODS AND MATERIALS We used ApcMin/+ mice, a well-studied CRC model, to examine acute versus fractionated proton radiation-induced differences in intestinal tumorigenesis and associated signaling pathways. Mice were exposed to 1.88 Gy of proton radiation delivered in a single fraction or in 4 equal daily fractions (0.47 Gy × 4). Intestinal tumor number and grade were scored 100 to 110 days after irradiation, and tumor and tumor-adjacent normal tissues were harvested to assess proliferative β-catenin/Akt pathways and DNA damage response and repair pathways relevant to colorectal carcinogenesis. RESULTS Significantly higher intestinal tumor number and grade, along with decreased differentiation, were observed after acute radiation relative to fractionated radiation. Acute protons induced upregulation of β-catenin and Akt pathways with increased proliferative marker phospho-histone H3. Increased DNA damage along with decreased DNA repair factors involved in mismatch repair and nonhomologous end joining were also observed after exposure to acute protons. CONCLUSIONS We show increased γH2AX, 53BP1, and 8-oxo-dG, suggesting that increased ongoing DNA damage along with decreased DNA repair factors and increased proliferative responses could be triggering a higher number of intestinal tumors after acute relative to fractionated proton exposures in ApcMin/+ mice. Taken together, our data suggest greater carcinogenic potential of acute relative to fractionated proton radiation.
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Affiliation(s)
- Shubhankar Suman
- Department of Biochemistry and Molecular & Cellular Biology, Georgetown University Medical Center, Washington, DC; Department of Oncology, Georgetown University Medical Center, Washington, DC
| | | | - Albert J Fornace
- Department of Biochemistry and Molecular & Cellular Biology, Georgetown University Medical Center, Washington, DC; Department of Oncology, Georgetown University Medical Center, Washington, DC
| | - Kamal Datta
- Department of Biochemistry and Molecular & Cellular Biology, Georgetown University Medical Center, Washington, DC; Department of Oncology, Georgetown University Medical Center, Washington, DC; Department of Pathology, Georgetown University Medical Center, Washington, DC.
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22
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Liu B, Hinshaw RG, Le KX, Park MA, Wang S, Belanger AP, Dubey S, Frost JL, Shi Q, Holton P, Trojanczyk L, Reiser V, Jones PA, Trigg W, Di Carli MF, Lorello P, Caldarone BJ, Williams JP, O'Banion MK, Lemere CA. Space-like 56Fe irradiation manifests mild, early sex-specific behavioral and neuropathological changes in wildtype and Alzheimer's-like transgenic mice. Sci Rep 2019; 9:12118. [PMID: 31431669 PMCID: PMC6702228 DOI: 10.1038/s41598-019-48615-1] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Accepted: 08/06/2019] [Indexed: 12/19/2022] Open
Abstract
Space travel will expose people to high-energy, heavy particle radiation, and the cognitive deficits induced by this exposure are not well understood. To investigate the short-term effects of space radiation, we irradiated 4-month-old Alzheimer’s disease (AD)-like transgenic (Tg) mice and wildtype (WT) littermates with a single, whole-body dose of 10 or 50 cGy 56Fe ions (1 GeV/u) at Brookhaven National Laboratory. At ~1.5 months post irradiation, behavioural testing showed sex-, genotype-, and dose-dependent changes in locomotor activity, contextual fear conditioning, grip strength, and motor learning, mainly in Tg but not WT mice. There was little change in general health, depression, or anxiety. Two months post irradiation, microPET imaging of the stable binding of a translocator protein ligand suggested no radiation-specific change in neuroinflammation, although initial uptake was reduced in female mice independently of cerebral blood flow. Biochemical and immunohistochemical analyses revealed that radiation reduced cerebral amyloid-β levels and microglia activation in female Tg mice, modestly increased microhemorrhages in 50 cGy irradiated male WT mice, and did not affect synaptic marker levels compared to sham controls. Taken together, we show specific short-term changes in neuropathology and behaviour induced by 56Fe irradiation, possibly having implications for long-term space travel.
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Affiliation(s)
- Bin Liu
- Department of Neurology, Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Boston, MA, 02115, USA.,Harvard Medical School, Boston, MA, 02115, USA
| | - Robert G Hinshaw
- Department of Neurology, Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Boston, MA, 02115, USA.,Harvard Medical School, Boston, MA, 02115, USA.,Harvard-MIT Division of Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Kevin X Le
- Department of Neurology, Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Boston, MA, 02115, USA
| | - Mi-Ae Park
- Harvard Medical School, Boston, MA, 02115, USA.,Department of Radiology, Brigham and Women's Hospital, Boston, MA, 02115, USA
| | - Shuyan Wang
- Department of Radiology, Brigham and Women's Hospital, Boston, MA, 02115, USA
| | - Anthony P Belanger
- Harvard Medical School, Boston, MA, 02115, USA.,Department of Radiology, Brigham and Women's Hospital, Boston, MA, 02115, USA
| | - Shipra Dubey
- Harvard Medical School, Boston, MA, 02115, USA.,Department of Radiology, Brigham and Women's Hospital, Boston, MA, 02115, USA
| | - Jeffrey L Frost
- 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.,Harvard Medical School, Boston, MA, 02115, USA
| | - Peter Holton
- Harvard Medical School, Boston, MA, 02115, USA.,Department of Radiology, Brigham and Women's Hospital, Boston, MA, 02115, USA
| | - Lee Trojanczyk
- Department of Neuroscience, University of Rochester Medical Center, Rochester, NY, 14642, USA
| | | | - Paul A Jones
- GE Healthcare, Chalfont St Giles, HP8 4SP, United Kingdom
| | - William Trigg
- GE Healthcare, Chalfont St Giles, HP8 4SP, United Kingdom
| | - Marcelo F Di Carli
- Harvard Medical School, Boston, MA, 02115, USA.,Department of Radiology, Brigham and Women's Hospital, Boston, MA, 02115, USA
| | - Paul Lorello
- Harvard Medical School Mouse Behavior Core, 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, 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. .,Harvard Medical School, Boston, MA, 02115, USA.
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23
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Cucinotta FA, Cacao E. Risks of cognitive detriments after low dose heavy ion and proton exposures. Int J Radiat Biol 2019; 95:985-998. [PMID: 31120359 PMCID: PMC6606350 DOI: 10.1080/09553002.2019.1623427] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Revised: 04/16/2019] [Accepted: 04/25/2019] [Indexed: 12/15/2022]
Abstract
Purpose: Heavy ion and proton brain irradiations occur during space travel and in Hadron therapy for cancer. Heavy ions produce distinct patterns of energy deposition in neuron cells and brain tissues compared to X-rays leading to large uncertainties in risk estimates. We make a critical review of findings from research studies over the last 25 years for understanding risks at low dose. Conclusions: A large number of mouse and rat cognitive testing measures have been reported for a variety of particle species and energies for acute doses. However, tissue reactions occur above dose thresholds and very few studies were performed at the heavy ion doses to be encountered on space missions (<0.04 Gy/y) or considered dose-rate effects, such that threshold doses are not known in rodent models. Investigations of possible mechanisms for cognitive changes have been limited by experimental design with largely group specific and not subject specific findings reported. Persistent oxidative stress and activated microglia cells are common mechanisms studied, while impairment of neurogenesis, detriments in neuron morphology, and changes to gene and protein expression were each found to be important in specific studies. Future research should focus on estimating threshold doses carried out with experimental designs aimed at understating causative mechanisms, which will be essential for extrapolating rodent findings to humans and chronic radiation scenarios, while establishing if mitigation are needed.
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24
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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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25
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Mineyeva OA, Bezriadnov DV, Kedrov AV, Lazutkin AA, Anokhin KV, Enikolopov GN. Radiation Induces Distinct Changes in Defined Subpopulations of Neural Stem and Progenitor Cells in the Adult Hippocampus. Front Neurosci 2019; 12:1013. [PMID: 30686979 PMCID: PMC6333747 DOI: 10.3389/fnins.2018.01013] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2018] [Accepted: 12/17/2018] [Indexed: 11/13/2022] Open
Abstract
While irradiation can effectively treat brain tumors, this therapy also causes cognitive impairments, some of which may stem from the disruption of hippocampal neurogenesis. To study how radiation affects neurogenesis, we combine phenotyping of subpopulations of hippocampal neural stem and progenitor cells with double- and triple S-phase labeling paradigms. Using this approach, we reveal new features of division, survival, and differentiation of neural stem and progenitor cells after exposure to gamma radiation. We show that dividing neural stem cells, while susceptible to damage induced by gamma rays, are less vulnerable than their rapidly amplifying progeny. We also show that dividing stem and progenitor cells that survive irradiation are suppressed in their ability to replicate 0.5–1 day after the radiation exposure. Suppression of division is also observed for cells that entered the cell cycle after irradiation or were not in the S phase at the time of exposure. Determining the longer term effects of irradiation, we found that 2 months after exposure, radiation-induced suppression of division is partially relieved for both stem and progenitor cells, without evidence for compensatory symmetric divisions as a means to restore the normal level of neurogenesis. By that time, most mature young neurons, born 2–4 weeks after the irradiation, still bear the consequences of radiation exposure, unlike younger neurons undergoing early stages of differentiation without overt signs of deficient maturation. Later, 6 months after an exposure to 5 Gy, cell proliferation and neurogenesis are further impaired, though neural stem cells are still available in the niche, and their pool is preserved. Our results indicate that various subpopulations of stem and progenitor cells in the adult hippocampus have different susceptibility to gamma radiation, and that neurogenesis, even after a temporary restoration, is impaired in the long term after exposure to gamma rays. Our study provides a framework for investigating critical issues of neural stem cell maintenance, aging, interaction with their microenvironment, and post-irradiation therapy.
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Affiliation(s)
- Olga A Mineyeva
- Moscow Institute of Physics and Technology, Dolgoprudny, Russia.,P. K. Anokhin Research Institute of Normal Physiology, Moscow, Russia.,National Research Center "Kurchatov Institute," Moscow, Russia
| | - Dmitri V Bezriadnov
- Moscow Institute of Physics and Technology, Dolgoprudny, Russia.,P. K. Anokhin Research Institute of Normal Physiology, Moscow, Russia
| | - Alexander V Kedrov
- Moscow Institute of Physics and Technology, Dolgoprudny, Russia.,P. K. Anokhin Research Institute of Normal Physiology, Moscow, Russia
| | - Alexander A Lazutkin
- Moscow Institute of Physics and Technology, Dolgoprudny, Russia.,P. K. Anokhin Research Institute of Normal Physiology, Moscow, Russia.,N.N. Burdenko Neurosurgery Institute, Moscow, Russia
| | - Konstantin V Anokhin
- Moscow Institute of Physics and Technology, Dolgoprudny, Russia.,P. K. Anokhin Research Institute of Normal Physiology, Moscow, Russia.,National Research Center "Kurchatov Institute," Moscow, Russia
| | - Grigori N Enikolopov
- Moscow Institute of Physics and Technology, Dolgoprudny, Russia.,Center for Developmental Genetics, Department of Anesthesiology, Stony Brook University, Stony Brook, NY, United States
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26
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Peng S, Yang B, Duan MY, Liu ZW, Wang WF, Zhang XZ, Ren BX, Tang FR. The Disparity of Impairment of Neurogenesis and Cognition After Acute or Fractionated Radiation Exposure in Adolescent BALB/c Mice. Dose Response 2019; 17:1559325818822574. [PMID: 30670940 PMCID: PMC6327339 DOI: 10.1177/1559325818822574] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2018] [Revised: 09/20/2018] [Accepted: 09/25/2018] [Indexed: 12/31/2022] Open
Abstract
The effect of acute X-ray irradiation with 2 Gy or fractionated exposure with 0.2 Gy continuously for 10 days (0.2 Gy × 10 = 2 Gy) was evaluated in the postnatal day 21 (P21) BALB/c mouse model. Both acute and fractionated irradiation induced impairment of cell proliferation and neurogenesis in the subgranular zone of the dentate gyrus labeled by Ki67 and doublecortin, respectively. Parvalbumin immunopositive interneurons in the subgranular zone were also reduced significantly. However, the 2 patterns of irradiation did not affect animal weight gain when measured at ages of P90 and P180 or 69 and 159 days after irradiation. Behavioral tests indicated that neither acute nor fractionated irradiation with a total dose of 2 Gy induced deficits in the contextual fear or spatial memory and memory for novel object recognition. Animal motor activity was also not affected in the open-field test. The disparity of the impairment of neurogenesis and unaffected cognition suggests that the severity of impairment of neurogenesis induced by acute or fractionated irradiation with a total dose of 2 Gy at P21 may not be worse enough to induce the deficit of cognition.
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Affiliation(s)
- Shuang Peng
- Health Center of Yangtze University, Jingzhou, Hubei, China
| | - Bo Yang
- Department of Medical Imaging Center, Renmin Hospital, Hubei University of Medicine, Shiyan, Hubei, People's Republic of China
| | - Meng Yun Duan
- Health Center of Yangtze University, Jingzhou, Hubei, China
| | - Zi Wei Liu
- Health Center of Yangtze University, Jingzhou, Hubei, China
| | - Wei Feng Wang
- Health Center of Yangtze University, Jingzhou, Hubei, China
| | - Xiang Zhi Zhang
- Affiliated Hospital of Yangtze University, Jingzhou, Hubei, People's Republic of China
| | - Bo Xu Ren
- Health Center of Yangtze University, Jingzhou, Hubei, China
| | - Feng Ru Tang
- Radiation Physiology Laboratory, Singapore Nuclear Research and Safety Initiative, National University of Singapore, Singapore
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27
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Cacao E, Kapukotuwa S, Cucinotta FA. Modeling Reveals the Dependence of Hippocampal Neurogenesis Radiosensitivity on Age and Strain of Rats. Front Neurosci 2018; 12:980. [PMID: 30618596 PMCID: PMC6306485 DOI: 10.3389/fnins.2018.00980] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2018] [Accepted: 12/07/2018] [Indexed: 12/13/2022] Open
Abstract
Cognitive dysfunction following radiation treatment for brain cancers in both children and adults have been correlated to impairment of neurogenesis in the hippocampal dentate gyrus. Various species and strains of rodent models have been used to study radiation-induced changes in neurogenesis and these investigations have utilized only a limited number of doses, dose-fractions, age and time after exposures conditions. In this paper, we have extended our previous mathematical model of radiation-induced hippocampal neurogenesis impairment of C57BL/6 mice to delineate the time, age, and dose dependent alterations in neurogenesis of a diverse strain of rats. To the best of our knowledge, this is the first predictive mathematical model to be published about hippocampal neurogenesis impairment for a variety of rat strains after acute or fractionated exposures to low linear energy transfer (low LET) radiation, such as X-rays and γ-rays, which are conventionally used in cancer radiation therapy. We considered four compartments to model hippocampal neurogenesis and its impairment following radiation exposures. Compartments include: (1) neural stem cells (NSCs), (2) neuronal progenitor cells or neuroblasts (NB), (3) immature neurons (ImN), and (4) glioblasts (GB). Additional consideration of dose and time after irradiation dependence of microglial activation and a possible shift of NSC proliferation from neurogenesis to gliogenesis at higher doses is established. Using a system of non-linear ordinary differential equations (ODEs), characterization of rat strain and age-related dynamics of hippocampal neurogenesis for unirradiated and irradiated conditions is developed. The model is augmented with the description of feedback regulation on early and late neuronal proliferation following radiation exposure. Predictions for dose-fraction regimes compared to acute radiation exposures, along with the dependence of neurogenesis sensitivity to radiation on age and strain of rats are discussed. A major result of this work is predictions of the rat strain and age dependent differences in radiation sensitivity and sub-lethal damage repair that can be used for predictions for arbitrary dose and dose-fractionation schedules.
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Affiliation(s)
| | | | - Francis A. Cucinotta
- Department of Health Physics and Diagnostic Sciences, University of Nevada, Las Vegas, NV, United States
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28
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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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29
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Koyama S, Narita E, Shinohara N, Miyakoshi J. Recovery kinetics of micronucleus formation by fractionated X-ray irradiation in various types of human cells. JOURNAL OF RADIATION RESEARCH 2018; 59:547-554. [PMID: 29961812 PMCID: PMC6151641 DOI: 10.1093/jrr/rry051] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/14/2018] [Revised: 04/16/2018] [Indexed: 06/08/2023]
Abstract
High-dose ionizing radiation is sufficient for breaking DNA strands, leading to cell death and mutations. By contrast, the effects of fractionated ionizing radiation on human-derived cells remain unclear. To better understand the genotoxic effects of fractionated ionizing radiation, as well as the cellular recovery rate, we investigated the frequency of micronucleus (MN) formation in various types of human cells. We irradiated cells with fractionated X-ray doses of 2 Gy at a rate of 0.0635 Gy/min, separated into two to eight smaller doses. After irradiation, we investigated the frequency of MN formation. In addition, we investigated the rate of decrease in MN frequency after irradiation with 1 or 2 Gy X-rays at various recovery periods. Fractionated irradiation decreased MN frequency in a dose-dependent manner. When the total dose of X-rays was the same, the MN frequencies were lower after fractionated X-ray irradiation than acute irradiation in every cell type examined. The rate of MN decrease was faster in KMST-6 cells, which were derived from a human embryo, than in the other cells. The rate of MN decrease was higher in cells exposed to fractionated X-rays than in those exposed to acute irradiation. Recovery rates were very similar among cell lines, except in KMST-6 cells, which recovered more rapidly than other cell types.
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Affiliation(s)
- Shin Koyama
- Kyoto University, Laboratory of Applied Radio Engineering for Humanosphere, Research Institute for Sustainable Humanosphere, Gokasho, Uji, Kyoto, Japan
| | - Eijiro Narita
- Kyoto University, Laboratory of Applied Radio Engineering for Humanosphere, Research Institute for Sustainable Humanosphere, Gokasho, Uji, Kyoto, Japan
| | - Naoki Shinohara
- Kyoto University, Laboratory of Applied Radio Engineering for Humanosphere, Research Institute for Sustainable Humanosphere, Gokasho, Uji, Kyoto, Japan
| | - Junji Miyakoshi
- Kyoto University, Laboratory of Applied Radio Engineering for Humanosphere, Research Institute for Sustainable Humanosphere, Gokasho, Uji, Kyoto, Japan
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30
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Begolly S, Olschowka JA, Love T, Williams JP, O'Banion MK. Fractionation enhances acute oligodendrocyte progenitor cell radiation sensitivity and leads to long term depletion. Glia 2017; 66:846-861. [PMID: 29288597 DOI: 10.1002/glia.23288] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Revised: 12/13/2017] [Accepted: 12/13/2017] [Indexed: 12/18/2022]
Abstract
Ionizing radiation (IR) is commonly used to treat central nervous system (CNS) cancers and metastases. While IR promotes remission, frequent side effects including impaired cognition and white matter loss occur following treatment. Fractionation is used to minimize these CNS late side effects, as it reduces IR effects in differentiated normal tissue, but not rapidly proliferating normal or tumor tissue. However, side effects occur even with the use of fractionated paradigms. Oligodendrocyte progenitor cells (OPCs) are a proliferative population within the CNS affected by radiation. We hypothesized that fractionated radiation would lead to OPC loss, which could contribute to the delayed white matter loss seen after radiation exposure. We found that fractionated IR induced a greater early loss of OPCs than an equivalent single dose exposure. Furthermore, OPC recovery was impaired following fractionated IR. Finally, reduced OPC differentiation and mature oligodendrocyte numbers occurred in single dose and fractionated IR paradigms. This work demonstrates that fractionation does not spare normal brain tissue and, importantly, highlights the sensitivity of OPCs to fractionated IR, suggesting that fractionated schedules may promote white matter dysfunction, a point that should be considered in radiotherapy.
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Affiliation(s)
- Sage Begolly
- Departments of Environmental Medicine, University of Rochester School of Medicine & Dentistry, Rochester, New York
| | - John A Olschowka
- Department of Neuroscience and Del Monte Neuroscience Institute, University of Rochester School of Medicine & Dentistry, Rochester, New York
| | - Tanzy Love
- Department of Biostatistics and Computational Biology, University of Rochester School of Medicine & Dentistry, Rochester, New York
| | - Jacqueline P Williams
- Departments of Environmental Medicine, University of Rochester School of Medicine & Dentistry, Rochester, New York.,Department of Radiation Oncology, University of Rochester School of Medicine & Dentistry, Rochester, New York
| | - M Kerry O'Banion
- Department of Neuroscience and Del Monte Neuroscience Institute, University of Rochester School of Medicine & Dentistry, Rochester, New York.,Department of Neurology, University of Rochester School of Medicine & Dentistry, Rochester, New York
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31
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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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Prognosis of Hippocampal Function after Sub-lethal Irradiation Brain Injury in Patients with Nasopharyngeal Carcinoma. Sci Rep 2017; 7:14697. [PMID: 29089622 PMCID: PMC5665929 DOI: 10.1038/s41598-017-13972-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2017] [Accepted: 10/04/2017] [Indexed: 12/21/2022] Open
Abstract
This work emphasizes the value of assessing hippocampal function by making a timely MRI-based prognosis following a minor dose of hippocampal irradiation after nasopharyngeal carcinomas (NPC) radiotherapy. A quasi-experiment with case-control design and functional assessments (e.g., neuroimaging analysis with fMRI) was conducted to assess hippocampal function after radiotherapy. We delivered 70 Gy of irradiation to nasopharyngeal carcinomas by 6MV helical radiotherapy and collected data from twenty NPC patients and 24 healthy age-matched subjects. Inevitably, hippocampi also received an average dose of 6.89 Gy (range, 2.0-14 Gy). Seed-based functional connectivity of the hippocampus was applied to estimate the cognitive alteration by time before, one month, and four months after irradiation. Afterward, longitudinal-and-cross-sessional statistical inference was determined with time-dependent measurement analysis of variance (ANOVA) with controlled covariance. Over time, there were longitudinal changes in the functional connectivity of hippocampal-related cortices, including the right middle frontal lobe, left superior temporal lobe, and left postcentral gyrus. The findings indicate the presence of functional plasticity, demonstrating how minor irradiation affects functional performance during the early delayed phase of irradiation-induced brain injury.
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Patel R, Arakawa H, Radivoyevitch T, Gerson SL, Welford SM. Long-Term Deficits in Behavior Performances Caused by Low- and High-Linear Energy Transfer Radiation. Radiat Res 2017; 188:672-680. [PMID: 28961076 DOI: 10.1667/rr14795.1] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Efforts to protect astronauts from harmful galactic cosmic radiation (GCR) require a better understanding of the effects of GCR on human health. In particular, little is known about the lasting effects of GCR on the central nervous system (CNS), which may lead to behavior performance deficits. Previous studies have shown that high-linear energy transfer (LET) radiation in rodents leads to short-term declines in a variety of behavior tests. However, the lasting impact of low-, medium- and high-LET radiation on behavior are not fully defined. Therefore, in this study C57BL/6 male mice were irradiated with 100 or 250 cGy of γ rays (LET ∼0.3 KeV/μm), 10 or 100 cGy of 1H at 1,000 MeV/n (LET ∼0.2 KeV/μm), 28Si at 300 MeV/n (LET ∼69 KeV/μm) or 56Fe at 600 MeV/n (LET of ∼180 KeV/μm), and behavior metrics were collected at 5 and 9 months postirradiation to analyze differences among radiation qualities and doses. A significant dose effect was observed on recognition memory and activity levels measured 9 months postirradiation, regardless of radiation source. In contrast, we observed that each ion species had a distinct effect on anxiety, motor coordination and spatial memory at extended time points. Although 28Si and 56Fe are both regarded as high-LET particles, they were shown to have different detrimental effects on behavior. In summary, our findings suggest that GCR not only affects the CNS in the short term, but also has lasting damaging effects on the CNS that can cause sustained declines in behavior performance.
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Affiliation(s)
| | | | - Tomas Radivoyevitch
- f Department of Quantitative Health Sciences, Cleveland Clinic, Cleveland, Ohio
| | - Stanton L Gerson
- d Case Comprehensive Cancer Center, Case Western Reserve University, Cleveland, Ohio.,e Seidman Cancer Center, University Hospitals, Cleveland, Ohio; and
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Tang FR, Loke WK, Wong P, Khoo BC. Radioprotective effect of ursolic acid in radiation-induced impairment of neurogenesis, learning and memory in adolescent BALB/c mouse. Physiol Behav 2017; 175:37-46. [PMID: 28341234 DOI: 10.1016/j.physbeh.2017.03.027] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2016] [Revised: 03/13/2017] [Accepted: 03/20/2017] [Indexed: 10/19/2022]
Abstract
The effect of acute irradiation with 5Gy or fractionated exposure with 0.5Gy continuously for 10days (a total dose of 5Gy) was evaluated in an immature BALB/c mouse model. Radioprotective effect of ursolic acid (at 25mg/kg/daily administered 1h after acute or each of fractionated irradiations, and continuously for 30days) was also investigated. We found that both acute and fractionated irradiation at a total dose of 5Gy did not induce any mortality within 30days after exposure to postnatal day 26 (P26) BALB/c mice, but reduced animal weigh gain in the first few weeks. At 90days after irradiation, the weight of animals with acute irradiation was still significantly lower than the control group; no significant difference though was observed for those fractionatedly exposed mice compared to the control group. Behavioral tests indicated that acute irradiation at 5Gy induced deficits in learning and memory in the contextual fear conditioning test. The memory for novel object recognition was also impaired. Similar changes were not observed in mice with fractionated irradiation. Immunohistochemical study demonstrated clearly that acute and fractionated irradiations induced impairment of neurogenesis in the subgranular zone (SGZ) of the dentate gyrus although fractionated exposure induced much lesser loss of newly generated neurons. Ursolic acid administered at 25mg/kg/daily for 30days after irradiation greatly improved acute irradiation-induced deficits in contextual learning and memory and in novel object recognition memory although it exacerbated radiation-induced reduction of neurogenesis in SGZ.
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Affiliation(s)
- Feng Ru Tang
- Radiation Physiology Laboratory, Singapore Nuclear Research and Safety initiative, National University of Singapore, 1 CREATE Way #04-01, CREATE Tower, 138602, Singapore.
| | - Weng Keong Loke
- Defence Medical and Environmental Research Institute, DSO National Laboratories, 11 Stockport Road, 11760, Singapore
| | - Peiyan Wong
- Neuroscience Phenotyping Core, Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, 117456, Singapore
| | - Boo Cheong Khoo
- Temasek Laboratories, National University of Singapore, 5A, Engineering Drive 1, 117411, Singapore
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35
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Cacao E, Cucinotta FA. Modeling Heavy-Ion Impairment of Hippocampal Neurogenesis after Acute and Fractionated Irradiation. Radiat Res 2016; 186:624-637. [PMID: 27925861 PMCID: PMC5545979 DOI: 10.1667/rr14569.1] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Radiation-induced impairment of neurogenesis in the hippocampal dentate gyrus is a concern due to its reported association with cognitive detriments after radiotherapy for brain cancers and the possible risks to astronauts chronically exposed to space radiation. Here, we have extended our recent work in a mouse model of impaired neurogenesis after exposure to low-linear energy transfer (LET) radiation to heavy ion irradiation. To our knowledge, this is the first report of a predictive mathematical model of radiation-induced changes to neurogenesis for a variety of radiation types after acute or fractionated irradiation. We used a system of nonlinear ordinary differential equations (ODEs) to represent age, time after exposure and dose-dependent changes to several cell populations participating in neurogenesis, as reported in mouse experiments. We considered four compartments to model hippocampal neurogenesis and, consequently, the effects of radiation in altering neurogenesis: 1. neural stem cells (NSCs); 2. neuronal progenitor cells or neuroblasts (NB); 3. immature neurons (ImN); and 4. glioblasts (GB), with additional consideration of microglial activation. The model describes the negative feedback regulation on early and late neuronal proliferation after irradiation, and the dynamics of the age dependence of neurogenesis. We compared our model to experimental data for X rays, and protons, carbon and iron particles, including data for fractionated iron-particle irradiation. Heavy-ion irradiation is predicted to lead to poor recovery or no recovery from impaired neurogenesis at doses as low as 0.5 Gy in mice. This is only partially ameliorated by dose fractionation, which suggests important implications for Hardon therapy near the Bragg peak, and possibly for space radiation exposures as well. Predictions of the threshold doses where neurogenesis recovery fails for given radiation types are described, and the role of subthreshold transient impairments are briefly discussed.
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Affiliation(s)
- Eliedonna Cacao
- Department of Health Physics and Diagnostic Sciences, University of Nevada, Las Vegas, Nevada
| | - Francis A. Cucinotta
- Department of Health Physics and Diagnostic Sciences, University of Nevada, Las Vegas, Nevada
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36
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Sweet TB, Hurley SD, Wu MD, Olschowka JA, Williams JP, O'Banion MK. Neurogenic Effects of Low-Dose Whole-Body HZE (Fe) Ion and Gamma Irradiation. Radiat Res 2016; 186:614-623. [PMID: 27905869 DOI: 10.1667/rr14530.1] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Understanding the dose-toxicity profile of radiation is critical when evaluating potential health risks associated with natural and man-made sources in our environment. The purpose of this study was to evaluate the effects of low-dose whole-body high-energy charged (HZE) iron (Fe) ions and low-energy gamma exposure on proliferation and differentiation of adult-born neurons within the dentate gyrus of the hippocampus, cells deemed to play a critical role in memory regulation. To determine the dose-response characteristics of the brain to whole-body Fe-ion vs. gamma-radiation exposure, C57BL/6J mice were irradiated with 1 GeV/n Fe ions or a static 137Cs source (0.662 MeV) at doses ranging from 0 to 300 cGy. The neurogenesis was analyzed at 48 h and one month postirradiation. These experiments revealed that whole-body exposure to either Fe ions or gamma radiation leads to: 1. An acute decrease in cell division within the dentate gyrus of the hippocampus, detected at doses as low as 30 and 100 cGy for Fe ions and gamma radiation, respectively; and 2. A reduction in newly differentiated neurons (DCX immunoreactivity) at one month postirradiation, with significant decreases detected at doses as low as 100 cGy for both Fe ions and gamma rays. The data presented here contribute to our understanding of brain responses to whole-body Fe ions and gamma rays and may help inform health-risk evaluations related to systemic exposure during a medical or radiologic/nuclear event or as a result of prolonged space travel.
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Affiliation(s)
- Tara B Sweet
- aDepartment of Neuroscience, University of Rochester School of Medicine and Dentistry, Rochester, New York 14642
| | - Sean D Hurley
- aDepartment of Neuroscience, University of Rochester School of Medicine and Dentistry, Rochester, New York 14642
| | - Michael D Wu
- aDepartment of Neuroscience, University of Rochester School of Medicine and Dentistry, Rochester, New York 14642
| | - John A Olschowka
- aDepartment of Neuroscience, University of Rochester School of Medicine and Dentistry, Rochester, New York 14642
| | - Jacqueline P Williams
- b Department of Environmental Medicine, University of Rochester School of Medicine and Dentistry, Rochester, New York 14642.,c Department of Radiation Oncology, University of Rochester School of Medicine and Dentistry, Rochester, New York 14642
| | - M Kerry O'Banion
- aDepartment of Neuroscience, University of Rochester School of Medicine and Dentistry, Rochester, New York 14642.,d Neurology, University of Rochester School of Medicine and Dentistry, Rochester, New York 14642
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37
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Zanni G, Di Martino E, Omelyanenko A, Andäng M, Delle U, Elmroth K, Blomgren K. Lithium increases proliferation of hippocampal neural stem/progenitor cells and rescues irradiation-induced cell cycle arrest in vitro. Oncotarget 2016; 6:37083-97. [PMID: 26397227 PMCID: PMC4741917 DOI: 10.18632/oncotarget.5191] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2015] [Accepted: 08/04/2015] [Indexed: 02/06/2023] Open
Abstract
Radiotherapy in children causes debilitating cognitive decline, partly linked to impaired neurogenesis. Irradiation targets primarily cancer cells but also endogenous neural stem/progenitor cells (NSPCs) leading to cell death or cell cycle arrest. Here we evaluated the effects of lithium on proliferation, cell cycle and DNA damage after irradiation of young NSPCs in vitro. NSPCs were treated with 1 or 3 mM LiCl and we investigated proliferation capacity (neurosphere volume and bromodeoxyuridine (BrdU) incorporation). Using flow cytometry, we analysed apoptosis (annexin V), cell cycle (propidium iodide) and DNA damage (γH2AX) after irradiation (3.5 Gy) of lithium-treated NSPCs. Lithium increased BrdU incorporation and, dose-dependently, the number of cells in replicative phase as well as neurosphere growth. Irradiation induced cell cycle arrest in G1 and G2/M phases. Treatment with 3 mM LiCl was sufficient to increase NSPCs in S phase, boost neurosphere growth and reduce DNA damage. Lithium did not affect the levels of apoptosis, suggesting that it does not rescue NSPCs committed to apoptosis due to accumulated DNA damage. Lithium is a very promising candidate for protection of the juvenile brain from radiotherapy and for its potential to thereby improve the quality of life for those children who survive their cancer.
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Affiliation(s)
- Giulia Zanni
- Center for Brain Repair and Rehabilitation, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.,Karolinska Institute, Department of Women's and Children's Health, Stockholm, Sweden
| | - Elena Di Martino
- Center for Brain Repair and Rehabilitation, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.,Karolinska Institute, Department of Women's and Children's Health, Stockholm, Sweden
| | - Anna Omelyanenko
- Karolinska Institute, Department of Physiology and Pharmacology, Stockholm, Sweden
| | - Michael Andäng
- Karolinska Institute, Department of Physiology and Pharmacology, Stockholm, Sweden.,Central European Institute of Technology, Masaryk University, Brno, Czech Republic
| | - Ulla Delle
- Department of Oncology, Institute of Clinical Sciences, Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden
| | - Kecke Elmroth
- Department of Oncology, Institute of Clinical Sciences, Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden
| | - Klas Blomgren
- Karolinska Institute, Department of Women's and Children's Health, Stockholm, Sweden
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Wyrobek AJ, Britten RA. Individual variations in dose response for spatial memory learning among outbred wistar rats exposed from 5 to 20 cGy of (56) Fe particles. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2016; 57:331-340. [PMID: 27237589 DOI: 10.1002/em.22018] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Accepted: 04/13/2016] [Indexed: 06/05/2023]
Abstract
Exposures of brain tissue to ionizing radiation can lead to persistent deficits in cognitive functions and behaviors. However, little is known about the quantitative relationships between exposure dose and neurological risks, especially for lower doses and among genetically diverse individuals. We investigated the dose relationship for spatial memory learning among genetically outbred male Wistar rats exposed to graded doses of (56) Fe particles (sham, 5, 10, 15, and 20 cGy; 1 GeV/n). Spatial memory learning was assessed on a Barnes maze using REL3 ratios measured at three months after exposure. Irradiated animals showed dose-dependent declines in spatial memory learning that were fit by a linear regression (P for slope <0.0002). The irradiated animals showed significantly impaired learning at 10 cGy exposures, no detectable learning between 10 and 15 cGy, and worsened performances between 15 and 20 cGy. The proportions of poor learners and the magnitude of their impairment were fit by linear regressions with doubling doses of ∼10 cGy. In contrast, there were no detectable deficits in learning among the good learners in this dose range. Our findings suggest that genetically diverse individuals can vary substantially in their spatial memory learning, and that exposures at low doses appear to preferentially impact poor learners. This hypothesis invites future investigations of the genetic and physiological mechanisms of inter-individual variations in brain function related to spatial memory learning after low-dose HZE radiation exposures and to determine whether it also applies to physical trauma to brain tissue and exposures to chemical neurotoxicants. Environ. Mol. Mutagen. 57:331-340, 2016. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Andrew J Wyrobek
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, University of California, Berkeley, California
| | - Richard A Britten
- Department of Radiation Oncology, and the Leroy T. Canoles Jr. Cancer Center, Eastern Virginia Medical School, Norfolk, Virginia
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39
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Britten RA, Jewell JS, Miller VD, Davis LK, Hadley MM, Wyrobek AJ. Impaired Spatial Memory Performance in Adult Wistar Rats Exposed to Low (5–20 cGy) Doses of 1 GeV/n56Fe Particles. Radiat Res 2016; 185:332-7. [DOI: 10.1667/rr14120.1] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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40
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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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41
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Ye F, Zhao T, Liu X, Jin X, Liu X, Wang T, Li Q. Long-term Autophagy and Nrf2 Signaling in the Hippocampi of Developing Mice after Carbon Ion Exposure. Sci Rep 2015; 5:18636. [PMID: 26689155 PMCID: PMC4686898 DOI: 10.1038/srep18636] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Accepted: 11/20/2015] [Indexed: 12/29/2022] Open
Abstract
To explore charged particle radiation-induced long-term hippocampus damage, we investigated the expression of autophagy and antioxidant Nrf2 signaling-related proteins in the mouse hippocampus after carbon ion radiation. Heads of immature female Balb/c mice were irradiated with carbon ions of different LETs at various doses. Behavioral tests were performed on the mice after maturation. Acute and chronic expression of LC3-II, p62/SQSTM1, nuclear Nrf2, activated caspase-3 and the Bax/Bcl-2 ratio were measured in the hippocampi. Secondary X-ray insult was adopted to amplify potential damages. Long-term behavioral changes were observed in high-LET carbon ion-irradiated mice. There were no differences in the rates of LC3-II induction and p62/SQSTM1 degradation compared to the control group regardless of whether the mice received the secondary X-ray insult. A high nuclear Nrf2 content and low apoptosis level in hippocampal cells subjected to secondary X-rays were observed for the mice exposed to relatively low-LET carbon ions. Therefore, carbon ion exposure in the immature mouse led to an LET-dependent behavioral change after maturation. Although autophagy was intact, the persistently high nuclear Nrf2 content in the hippocampus might account for the unchanged behavioral pattern in mice exposed to the relatively low-LET carbon ions and the subsequent increased radioresistance of the hippocampus.
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Affiliation(s)
- Fei Ye
- Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China.,Department of Modern Physics, Lanzhou University, Lanzhou 730000, China.,University of Chinese Academy of Sciences, Beijing 100049, China.,Key Laboratory of Heavy Ion Radiation Biology and Medicine of Chinese Academy of Sciences, Lanzhou 730000, China
| | - Ting Zhao
- Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China.,Key Laboratory of Heavy Ion Radiation Biology and Medicine of Chinese Academy of Sciences, Lanzhou 730000, China
| | - Xiongxiong Liu
- Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China.,Key Laboratory of Heavy Ion Radiation Biology and Medicine of Chinese Academy of Sciences, Lanzhou 730000, China
| | - Xiaodong Jin
- Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China.,Key Laboratory of Heavy Ion Radiation Biology and Medicine of Chinese Academy of Sciences, Lanzhou 730000, China
| | - Xinguo Liu
- Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China.,Key Laboratory of Heavy Ion Radiation Biology and Medicine of Chinese Academy of Sciences, Lanzhou 730000, China
| | - Tieshan Wang
- Department of Modern Physics, Lanzhou University, Lanzhou 730000, China
| | - Qiang Li
- Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China.,Key Laboratory of Heavy Ion Radiation Biology and Medicine of Chinese Academy of Sciences, Lanzhou 730000, China
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42
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Son Y, Yang M, Wang H, Moon C. Hippocampal dysfunctions caused by cranial irradiation: a review of the experimental evidence. Brain Behav Immun 2015; 45:287-96. [PMID: 25596174 DOI: 10.1016/j.bbi.2015.01.007] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/22/2014] [Revised: 01/06/2015] [Accepted: 01/08/2015] [Indexed: 12/11/2022] Open
Abstract
Cranial irradiation (IR) is commonly used for the treatment of brain tumors but may cause disastrous brain injury, especially in the hippocampus, which has important cognition and emotional regulation functions. Several preclinical studies have investigated the mechanisms associated with cranial IR-induced hippocampal dysfunction such as memory defects and depression-like behavior. However, current research on hippocampal dysfunction and its associated mechanisms, with the ultimate goal of overcoming the side effects of cranial radiation therapy in the hippocampus, is still very much in progress. This article reviews several in vivo studies on the possible mechanisms of radiation-induced hippocampal dysfunction, which may be associated with hippocampal neurogenesis, neurotrophin and neuroinflammation. Thus, this review may be helpful to gain new mechanistic insights into hippocampal dysfunction following cranial IR and provide effective strategies for potential therapeutic approaches for cancer patients receiving radiation therapy.
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Affiliation(s)
- Yeonghoon Son
- Department of Veterinary Anatomy, College of Veterinary Medicine, Chonnam National University, Gwangju 500-757, South Korea
| | - Miyoung Yang
- Department of Physiology and Neuroscience Program, Michigan State University, East Lansing, MI 48824, USA
| | - Hongbing Wang
- Department of Physiology and Neuroscience Program, Michigan State University, East Lansing, MI 48824, USA
| | - Changjong Moon
- Department of Veterinary Anatomy, College of Veterinary Medicine, Chonnam National University, Gwangju 500-757, South Korea.
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43
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Poulose SM, Bielinski DF, Carrihill-Knoll KL, Rabin BM, Shukitt-Hale B. Protective effects of blueberry- and strawberry diets on neuronal stress following exposure to 56Fe particles. Brain Res 2014; 1593:9-18. [DOI: 10.1016/j.brainres.2014.10.028] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2014] [Revised: 10/14/2014] [Accepted: 10/15/2014] [Indexed: 12/29/2022]
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44
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DeCarolis NA, Rivera PD, Ahn F, Amaral WZ, LeBlanc JA, Malhotra S, Shih HY, Petrik D, Melvin N, Chen BP, Eisch AJ. 56Fe Particle Exposure Results in a Long-Lasting Increase in a Cellular Index of Genomic Instability and Transiently Suppresses Adult Hippocampal Neurogenesis in Vivo. LIFE SCIENCES IN SPACE RESEARCH 2014; 2:70-79. [PMID: 25170435 PMCID: PMC4142527 DOI: 10.1016/j.lssr.2014.06.004] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
The high-LET HZE particles from galactic cosmic radiation pose tremendous health risks to astronauts, as they may incur sub-threshold brain injury or maladaptations that may lead to cognitive impairment. The health effects of HZE particles are difficult to predict and unfeasible to prevent. This underscores the importance of estimating radiation risks to the central nervous system as a whole as well as to specific brain regions like the hippocampus, which is central to learning and memory. Given that neurogenesis in the hippocampus has been linked to learning and memory, we investigated the response and recovery of neurogenesis and neural stem cells in the adult mouse hippocampal dentate gyrus after HZE particle exposure using two nestin transgenic reporter mouse lines to label and track radial glia stem cells (Nestin-GFP and Nestin-CreERT2/R26R:YFP mice, respectively). Mice were subjected to 56Fe particle exposure (0 or 1 Gy, at either 300 or 1000 MeV/n) and brains were harvested at early (24h), intermediate (7d), and/or long time points (2-3mo) post-irradiation. 56Fe particle exposure resulted in a robust increase in 53BP1+ foci at both the intermediate and long time points post-irradiation, suggesting long-term genomic instability in the brain. However, 56Fe particle exposure only produced a transient decrease in immature neuron number at the intermediate time point, with no significant decrease at the long time point post-irradiation. 56Fe particle exposure similarly produced a transient decrease in dividing progenitors, with fewer progenitors labeled at the early time point but equal number labeled at the intermediate time point, suggesting a recovery of neurogenesis. Notably, 56Fe particle exposure did not change the total number of nestin-expressing neural stem cells. These results highlight that despite the persistence of an index of genomic instability, 56Fe particle-induced deficits in adult hippocampal neurogenesis may be transient. These data support the regenerative capacity of the adult SGZ after HZE particle exposure and encourage additional inquiry into the relationship between radial glia stem cells and cognitive function after HZE particle exposure.
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Affiliation(s)
| | | | - Francisca Ahn
- Dept Radiation Oncology, UT Southwestern Medical Center, Dallas, TX, USA
| | | | - Junie A. LeBlanc
- Dept Psychiatry, UT Southwestern Medical Center, Dallas, TX, USA
| | - Shveta Malhotra
- Dept Psychiatry, UT Southwestern Medical Center, Dallas, TX, USA
| | - Hung-Ying Shih
- Dept Radiation Oncology, UT Southwestern Medical Center, Dallas, TX, USA
| | - David Petrik
- Dept Psychiatry, UT Southwestern Medical Center, Dallas, TX, USA
| | - Neal Melvin
- Dept Psychiatry, UT Southwestern Medical Center, Dallas, TX, USA
| | - Benjamin P.C. Chen
- Dept Radiation Oncology, UT Southwestern Medical Center, Dallas, TX, USA
- Co-Corresponding Authors: Amelia J. Eisch, Department of Psychiatry, UT Southwestern Medical Center, Dallas, TX 75390-9070. . Benjamin P. C. Chen, Department of Radiation Oncology, UT Southwestern Medical Center, Dallas, TX 75390-9187.
| | - Amelia J. Eisch
- Dept Psychiatry, UT Southwestern Medical Center, Dallas, TX, USA
- Co-Corresponding Authors: Amelia J. Eisch, Department of Psychiatry, UT Southwestern Medical Center, Dallas, TX 75390-9070. . Benjamin P. C. Chen, Department of Radiation Oncology, UT Southwestern Medical Center, Dallas, TX 75390-9187.
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Latchney SE, Rivera PD, Mao XW, Ferguson VL, Bateman TA, Stodieck LS, Nelson GA, Eisch AJ. The effect of spaceflight on mouse olfactory bulb volume, neurogenesis, and cell death indicates the protective effect of novel environment. J Appl Physiol (1985) 2014; 116:1593-604. [PMID: 24744382 DOI: 10.1152/japplphysiol.01174.2013] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Space missions necessitate physiological and psychological adaptations to environmental factors not present on Earth, some of which present significant risks for the central nervous system (CNS) of crewmembers. One CNS region of interest is the adult olfactory bulb (OB), as OB structure and function are sensitive to environmental- and experience-induced regulation. It is currently unknown how the OB is altered by spaceflight. In this study, we evaluated OB volume and neurogenesis in mice shortly after a 13-day flight on Space Shuttle Atlantis [Space Transport System (STS)-135] relative to two groups of control mice maintained on Earth. Mice housed on Earth in animal enclosure modules that mimicked the conditions onboard STS-135 (AEM-Ground mice) had greater OB volume relative to mice maintained in standard housing on Earth (Vivarium mice), particularly in the granule (GCL) and glomerular (GL) cell layers. AEM-Ground mice also had more OB neuroblasts and fewer apoptotic cells relative to Vivarium mice. However, the AEM-induced increase in OB volume and neurogenesis was not seen in STS-135 mice (AEM-Flight mice), suggesting that spaceflight may have negated the positive effects of the AEM. In fact, when OB volume of AEM-Flight mice was considered, there was a greater density of apoptotic cells relative to AEM-Ground mice. Our findings suggest that factors present during spaceflight have opposing effects on OB size and neurogenesis, and provide insight into potential strategies to preserve OB structure and function during future space missions.
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Affiliation(s)
- Sarah E Latchney
- Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Phillip D Rivera
- Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Xiao W Mao
- Department of Basic Sciences, Division of Radiation Research, Loma Linda University and Medical Center, Loma Linda, California
| | - Virginia L Ferguson
- Department of Mechanical Engineering, University of Colorado at Boulder, Boulder, Colorado; and
| | - Ted A Bateman
- Department of Biomedical Engineering, University of North Carolina, Chapel Hill, North Carolina
| | - Louis S Stodieck
- BioServe Space Technologies, Aerospace Engineering Sciences, University of Colorado at Boulder, Boulder, Colorado
| | - Gregory A Nelson
- Department of Basic Sciences, Division of Radiation Research, Loma Linda University and Medical Center, Loma Linda, California
| | - Amelia J Eisch
- Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, Texas;
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46
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Kennedy AR. Biological Effects of Space Radiation and Development of Effective Countermeasures. LIFE SCIENCES IN SPACE RESEARCH 2014; 1:10-43. [PMID: 25258703 PMCID: PMC4170231 DOI: 10.1016/j.lssr.2014.02.004] [Citation(s) in RCA: 89] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
As part of a program to assess the adverse biological effects expected from astronaut exposure to space radiation, numerous different biological effects relating to astronaut health have been evaluated. There has been major focus recently on the assessment of risks related to exposure to solar particle event (SPE) radiation. The effects related to various types of space radiation exposure that have been evaluated are: gene expression changes (primarily associated with programmed cell death and extracellular matrix (ECM) remodeling), oxidative stress, gastrointestinal tract bacterial translocation and immune system activation, peripheral hematopoietic cell counts, emesis, blood coagulation, skin, behavior/fatigue (including social exploration, submaximal exercise treadmill and spontaneous locomotor activity), heart functions, alterations in biological endpoints related to astronaut vision problems (lumbar puncture/intracranial pressure, ocular ultrasound and histopathology studies), and survival, as well as long-term effects such as cancer and cataract development. A number of different countermeasures have been identified that can potentially mitigate or prevent the adverse biological effects resulting from exposure to space radiation.
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Affiliation(s)
- Ann R Kennedy
- Department of Radiation Oncology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104-6072
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