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Yun S, Soler I, Tran FH, Haas HA, Shi R, Bancroft GL, Suarez M, de Santis CR, Reynolds RP, Eisch AJ. Behavioral pattern separation and cognitive flexibility are enhanced in a mouse model of increased lateral entorhinal cortex-dentate gyrus circuit activity. Front Behav Neurosci 2023; 17:1151877. [PMID: 37324519 PMCID: PMC10267474 DOI: 10.3389/fnbeh.2023.1151877] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Accepted: 04/26/2023] [Indexed: 06/17/2023] Open
Abstract
Behavioral pattern separation and cognitive flexibility are essential cognitive abilities that are disrupted in many brain disorders. A better understanding of the neural circuitry involved in these abilities will open paths to treatment. In humans and mice, discrimination and adaptation rely on the integrity of the hippocampal dentate gyrus (DG) which receives glutamatergic input from the entorhinal cortex (EC), including the lateral EC (LEC). An inducible increase of EC-DG circuit activity improves simple hippocampal-dependent associative learning and increases DG neurogenesis. Here, we asked if the activity of LEC fan cells that directly project to the DG (LEC → DG neurons) regulates the relatively more complex hippocampal-dependent abilities of behavioral pattern separation or cognitive flexibility. C57BL/6J male mice received bilateral LEC infusions of a virus expressing shRNA TRIP8b, an auxiliary protein of an HCN channel or a control virus (SCR shRNA). Prior work shows that 4 weeks post-surgery, TRIP8b mice have more DG neurogenesis and greater activity of LEC → DG neurons compared to SCR shRNA mice. Here, 4 weeks post-surgery, the mice underwent testing for behavioral pattern separation and reversal learning (touchscreen-based location discrimination reversal [LDR]) and innate fear of open spaces (elevated plus maze [EPM]) followed by quantification of new DG neurons (doublecortin-immunoreactive cells [DCX+] cells). There was no effect of treatment (SCR shRNA vs. TRIP8b) on performance during general touchscreen training, LDR training, or the 1st days of LDR testing. However, in the last days of LDR testing, the TRIP8b shRNA mice had improved pattern separation (reached the first reversal more quickly and had more accurate discrimination) compared to the SCR shRNA mice, specifically when the load on pattern separation was high (lit squares close together or "small separation"). The TRIP8b shRNA mice were also more cognitively flexible (achieved more reversals) compared to the SCR shRNA mice in the last days of LDR testing. Supporting a specific influence on cognitive behavior, the SCR shRNA and TRIP8b shRNA mice did not differ in total distance traveled or in time spent in the closed arms of the EPM. Supporting an inducible increase in LEC-DG activity, DG neurogenesis was increased. These data indicate that the TRIP8b shRNA mice had better pattern separation and reversal learning and more neurogenesis compared to the SCR shRNA mice. This study advances fundamental and translational neuroscience knowledge relevant to two cognitive functions critical for adaptation and survival-behavioral pattern separation and cognitive flexibility-and suggests that the activity of LEC → DG neurons merits exploration as a therapeutic target to normalize dysfunctional DG behavioral output.
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Affiliation(s)
- Sanghee Yun
- Department of Anesthesiology and Critical Care Medicine, Children's Hospital of Philadelphia, Philadelphia, PA, United States
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Ivan Soler
- Department of Anesthesiology and Critical Care Medicine, Children's Hospital of Philadelphia, Philadelphia, PA, United States
- University of Pennsylvania, Philadelphia, PA, United States
| | - Fionya H. Tran
- Department of Anesthesiology and Critical Care Medicine, Children's Hospital of Philadelphia, Philadelphia, PA, United States
| | - Harley A. Haas
- University of Pennsylvania, Philadelphia, PA, United States
| | - Raymon Shi
- University of Pennsylvania, Philadelphia, PA, United States
| | | | - Maiko Suarez
- Department of Anesthesiology and Critical Care Medicine, Children's Hospital of Philadelphia, Philadelphia, PA, United States
| | - Christopher R. de Santis
- Department of Anesthesiology and Critical Care Medicine, Children's Hospital of Philadelphia, Philadelphia, PA, United States
| | - Ryan P. Reynolds
- Department of Anesthesiology and Critical Care Medicine, Children's Hospital of Philadelphia, Philadelphia, PA, United States
| | - Amelia J. Eisch
- Department of Anesthesiology and Critical Care Medicine, Children's Hospital of Philadelphia, Philadelphia, PA, United States
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
- Department of Neuroscience and Mahoney Institute for Neurosciences, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
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Yun S, Soler I, Tran F, Haas HA, Shi R, Bancroft GL, Suarez M, de Santis CR, Reynolds RP, Eisch AJ. Behavioral pattern separation and cognitive flexibility are enhanced in a mouse model of increased lateral entorhinal cortex-dentate gyrus circuit activity. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.26.525756. [PMID: 36747871 PMCID: PMC9900985 DOI: 10.1101/2023.01.26.525756] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Behavioral pattern separation and cognitive flexibility are essential cognitive abilities which are disrupted in many brain disorders. Better understanding of the neural circuitry involved in these abilities will open paths to treatment. In humans and mice, discrimination and adaptation rely on integrity of the hippocampal dentate gyrus (DG) which both receive glutamatergic input from the entorhinal cortex (EC), including the lateral EC (LEC). Inducible increase of EC-DG circuit activity improves simple hippocampal-dependent associative learning and increases DG neurogenesis. Here we asked if the activity of LEC fan cells that directly project to the DG (LEC➔DG neurons) regulates behavioral pattern separation or cognitive flexibility. C57BL6/J male mice received bilateral LEC infusions of a virus expressing shRNA TRIP8b, an auxiliary protein of an HCN channel or a control virus (SCR shRNA); this approach increases the activity of LEC➔DG neurons. Four weeks later, mice underwent testing for behavioral pattern separation and reversal learning (touchscreen-based Location Discrimination Reversal [LDR] task) and innate fear of open spaces (elevated plus maze [EPM]) followed by counting of new DG neurons (doublecortin-immunoreactive cells [DCX+] cells). TRIP8b and SCR shRNA mice performed similarly in general touchscreen training and LDR training. However, in late LDR testing, TRIP8b shRNA mice reached the first reversal more quickly and had more accurate discrimination vs. SCR shRNA mice, specifically when pattern separation was challenging (lit squares close together or "small separation"). Also, TRIP8b shRNA mice achieved more reversals in late LDR testing vs. SCR shRNA mice. Supporting a specific influence on cognitive behavior, SCR shRNA and TRIP8b shRNA mice did not differ in total distance traveled or in time spent in the closed arms of the EPM. Supporting an inducible increase in LEC-DG activity, DG neurogenesis was increased. These data indicate TRIP8b shRNA mice had better pattern separation and reversal learning and more neurogenesis vs. SCR shRNA mice. This work advances fundamental and translational neuroscience knowledge relevant to two cognitive functions critical for adaptation and survival - behavioral pattern separation and cognitive flexibility - and suggests the activity of LEC➔DG neurons merits exploration as a therapeutic target to normalize dysfunctional DG behavioral output.
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Risk of Developing Non-Cancerous Central Nervous System Diseases Due to Ionizing Radiation Exposure during Adulthood: Systematic Review and Meta-Analyses. Brain Sci 2022; 12:brainsci12080984. [PMID: 35892428 PMCID: PMC9331299 DOI: 10.3390/brainsci12080984] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Revised: 07/20/2022] [Accepted: 07/22/2022] [Indexed: 02/01/2023] Open
Abstract
Background: High-dose ionizing radiation (IR) (>0.5 Gy) is an established risk factor for cognitive impairments, but this cannot be concluded for low-to-moderate IR exposure (<0.5 Gy) in adulthood as study results are inconsistent. The objectives are to summarize relevant epidemiological studies of low-to-moderate IR exposure in adulthood and to assess the risk of non-cancerous CNS diseases. Methods: A systematic literature search of four electronic databases was performed to retrieve relevant epidemiological studies published from 2000 to 2022. Pooled standardized mortality ratios, relative risks, and excess relative risks (ERR) were estimated with a random effect model. Results: Forty-five publications were included in the systematic review, including thirty-three in the quantitative meta-analysis. The following sources of IR-exposure were considered: atomic bomb, occupational, environmental, and medical exposure. Increased dose-risk relationships were found for cerebrovascular diseases incidence and mortality (ERRpooled per 100 mGy = 0.04; 95% CI: 0.03−0.05; ERRpooled at 100 mGy = 0.01; 95% CI: −0.00−0.02, respectively) and for Parkinson’s disease (ERRpooled at 100 mGy = 0.11; 95% CI: 0.06−0.16); Conclusions: Our findings suggest that adult low-to-moderate IR exposure may have effects on non-cancerous CNS diseases. Further research addressing inherent variation issues is encouraged.
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Shaler T, Lin H, Bakke J, Chen S, Grover A, Chang P. Particle radiation-induced dysregulation of protein homeostasis in primary human and mouse neuronal cells. LIFE SCIENCES IN SPACE RESEARCH 2020; 25:9-17. [PMID: 32414496 DOI: 10.1016/j.lssr.2020.02.003] [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: 10/28/2019] [Revised: 02/12/2020] [Accepted: 02/16/2020] [Indexed: 06/11/2023]
Abstract
Space particle radiations may cause significant damage to proteins and oxidative stress in the cells within the central nervous system and pose a potential health hazard to humans in long-term manned space explorations. Dysregulation of the ubiquitin-proteasome system as evidenced by abnormal accumulation of polyubiquitin (pUb) chain linkages has been implicated in several age-related neurodegenerative disorders by mechanisms that may involve the inter-neuronal spread of toxic misfolded proteins, the induction of chronic neuroinflammation, or the inappropriate inhibition or activation of key enzymes, which could lead to dysfunction in, for example, proteolysis, or the accumulation of post-translationally-modified substrates.In this study, we employed a quantitative proteomics method to evaluate the impact of particle-radiation induced alterations in three major pUb-linked chains at lysine residues Lys-48 (K-48), Lys-63 (K-63), and Lys-11 (K-11), and probed for global proteomic changes in mouse and human neural cells that were irradiated with low doses of 250 MeV proton, 260 MeV/u silicon or 1 GeV/u iron ions. We found significant accumulation in K-48 linkage after 1 Gy protons and K-63 linkage after 0.5 Gy iron ions in human neural cells. Cells derived from different regions of the mouse brain (cortex, striatum and mesencephalon) showed differential sensitivity to particle radiation exposure. Although none of the linkages were altered after proton exposure, both K-48 and K-63 linkages in mouse striatal neuronal cells were elevated after 0.5 Gy of silicon or iron ions. Changes were also seen in proteins commonly used as markers of neural progenitor and stem cells, in DNA binding/damage repair and cellular redox pathways. In contrast, no significant changes were observed at the same time point after proton irradiation. These results suggest that the quality of the particle radiation plays a key role in the level, linkage and cell type specificity of protein homeostasis in key populations of neuronal cells.
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Affiliation(s)
- Tom Shaler
- SRI International, 333 Ravenswood Ave, Menlo Park, CA 94025 United States
| | - Hua Lin
- SRI International, 333 Ravenswood Ave, Menlo Park, CA 94025 United States
| | - James Bakke
- SRI International, 333 Ravenswood Ave, Menlo Park, CA 94025 United States
| | - Sophia Chen
- SRI International, 333 Ravenswood Ave, Menlo Park, CA 94025 United States
| | - Amber Grover
- SRI International, 333 Ravenswood Ave, Menlo Park, CA 94025 United States
| | - Polly Chang
- SRI International, 333 Ravenswood Ave, Menlo Park, CA 94025 United States.
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Kiffer F, Boerma M, Allen A. Behavioral effects of space radiation: A comprehensive review of animal studies. LIFE SCIENCES IN SPACE RESEARCH 2019; 21:1-21. [PMID: 31101151 PMCID: PMC7150604 DOI: 10.1016/j.lssr.2019.02.004] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Revised: 02/14/2019] [Accepted: 02/17/2019] [Indexed: 05/04/2023]
Abstract
As NASA prepares for the first manned mission to Mars in the next 20 years, close attention has been placed on the cognitive welfare of astronauts, who will likely endure extended durations in confinement and microgravity and be subjected to the radioactive charged particles travelling at relativistic speeds in interplanetary space. The future of long-duration manned spaceflight, thus, depends on understanding the individual hazards associated with the environment beyond Earth's protective magnetosphere. Ground-based single-particle studies of exposed mice and rats have, in the last 30 years, overwhelmingly reported deficits in their cognitive behaviors. However, as particle-accelerator technologies at NASA's Space Radiation Laboratory continue to progress, more realistic representations of space radiation are materializing, including multiple-particle exposures and, eventually, at multiple energy distributions. These advancements help determine how to best mitigate possible hazards due to space radiation. However, risk models will depend on delineating which particles are most responsible for specific behavioral outcomes and whether multiple-particle exposures produce synergistic effects. Here, we review the literature on animal exposures by particle, energy, and behavioral assay to inform future mixed-field radiation studies of possible behavioral outcomes.
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Affiliation(s)
- Frederico Kiffer
- Division of Radiation Health, College of Pharmacy, University of Arkansas for Medical Sciences, Little Rock, AR, United States; Department of Pharmaceutical Sciences, College of Pharmacy, University of Arkansas for Medical Sciences, Little Rock, AR, United States.
| | - Marjan Boerma
- Division of Radiation Health, College of Pharmacy, University of Arkansas for Medical Sciences, Little Rock, AR, United States; Department of Pharmaceutical Sciences, College of Pharmacy, University of Arkansas for Medical Sciences, Little Rock, AR, United States.
| | - Antiño Allen
- Division of Radiation Health, College of Pharmacy, University of Arkansas for Medical Sciences, Little Rock, AR, United States; Department of Pharmaceutical Sciences, College of Pharmacy, University of Arkansas for Medical Sciences, Little Rock, AR, United States; Department of Neurobiology & Developmental Sciences, College of Medicine, University of Arkansas for Medical Sciences, Little Rock, AR, United States.
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Whole-Body 12C Irradiation Transiently Decreases Mouse Hippocampal Dentate Gyrus Proliferation and Immature Neuron Number, but Does Not Change New Neuron Survival Rate. Int J Mol Sci 2018; 19:ijms19103078. [PMID: 30304778 PMCID: PMC6213859 DOI: 10.3390/ijms19103078] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Revised: 09/17/2018] [Accepted: 09/21/2018] [Indexed: 02/08/2023] Open
Abstract
High-charge and -energy (HZE) particles comprise space radiation and they pose a challenge to astronauts on deep space missions. While exposure to most HZE particles decreases neurogenesis in the hippocampus—a brain structure important in memory—prior work suggests that 12C does not. However, much about 12C’s influence on neurogenesis remains unknown, including the time course of its impact on neurogenesis. To address this knowledge gap, male mice (9–11 weeks of age) were exposed to whole-body 12C irradiation 100 cGy (IRR; 1000 MeV/n; 8 kEV/µm) or Sham treatment. To birthdate dividing cells, mice received BrdU i.p. 22 h post-irradiation and brains were harvested 2 h (Short-Term) or three months (Long-Term) later for stereological analysis indices of dentate gyrus neurogenesis. For the Short-Term time point, IRR mice had fewer Ki67, BrdU, and doublecortin (DCX) immunoreactive (+) cells versus Sham mice, indicating decreased proliferation (Ki67, BrdU) and immature neurons (DCX). For the Long-Term time point, IRR and Sham mice had similar Ki67+ and DCX+ cell numbers, suggesting restoration of proliferation and immature neurons 3 months post-12C irradiation. IRR mice had fewer surviving BrdU+ cells versus Sham mice, suggesting decreased cell survival, but there was no difference in BrdU+ cell survival rate when compared within treatment and across time point. These data underscore the ability of neurogenesis in the mouse brain to recover from the detrimental effect of 12C exposure.
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Impey S, Jopson T, Pelz C, Tafessu A, Fareh F, Zuloaga D, Marzulla T, Riparip LK, Stewart B, Rosi S, Turker MS, Raber J. Bi-directional and shared epigenomic signatures following proton and 56Fe irradiation. Sci Rep 2017; 7:10227. [PMID: 28860502 PMCID: PMC5579159 DOI: 10.1038/s41598-017-09191-4] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2017] [Accepted: 07/24/2017] [Indexed: 12/04/2022] Open
Abstract
The brain’s response to radiation exposure is an important concern for patients undergoing cancer therapy and astronauts on long missions in deep space. We assessed whether this response is specific and prolonged and is linked to epigenetic mechanisms. We focused on the response of the hippocampus at early (2-weeks) and late (20-week) time points following whole body proton irradiation. We examined two forms of DNA methylation, cytosine methylation (5mC) and hydroxymethylation (5hmC). Impairments in object recognition, spatial memory retention, and network stability following proton irradiation were observed at the two-week time point and correlated with altered gene expression and 5hmC profiles that mapped to specific gene ontology pathways. Significant overlap was observed between DNA methylation changes at the 2 and 20-week time points demonstrating specificity and retention of changes in response to radiation. Moreover, a novel class of DNA methylation change was observed following an environmental challenge (i.e. space irradiation), characterized by both increased and decreased 5hmC levels along the entire gene body. These changes were mapped to genes encoding neuronal functions including postsynaptic gene ontology categories. Thus, the brain’s response to proton irradiation is both specific and prolonged and involves novel remodeling of non-random regions of the epigenome.
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Affiliation(s)
- Soren Impey
- Oregon Stem Cell Center and Department of Pediatrics, Oregon Health and Science University, Portland, OR, 97239, USA. .,Department of Cell and Developmental Biology, Oregon Health and Science University, Portland, OR, 97239, USA.
| | - Timothy Jopson
- Brain and Spinal Injury Center, Departments of Neurological Surgery and Physical Therapy and Rehabilitation Science, University of California, San Francisco, San Francisco, CA, 94110, USA
| | - Carl Pelz
- Oregon Stem Cell Center and Department of Pediatrics, Oregon Health and Science University, Portland, OR, 97239, USA
| | - Amanuel Tafessu
- Oregon Stem Cell Center and Department of Pediatrics, Oregon Health and Science University, Portland, OR, 97239, USA
| | - Fatema Fareh
- Oregon Stem Cell Center and Department of Pediatrics, Oregon Health and Science University, Portland, OR, 97239, USA
| | - Damian Zuloaga
- Department of Behavioral Neuroscience, Oregon Health and Science University, Portland, OR, 97239, USA
| | - Tessa Marzulla
- Department of Behavioral Neuroscience, Oregon Health and Science University, Portland, OR, 97239, USA
| | - Lara-Kirstie Riparip
- Brain and Spinal Injury Center, Departments of Neurological Surgery and Physical Therapy and Rehabilitation Science, University of California, San Francisco, San Francisco, CA, 94110, USA
| | - Blair Stewart
- Department of Behavioral Neuroscience, Oregon Health and Science University, Portland, OR, 97239, USA
| | - Susanna Rosi
- Brain and Spinal Injury Center, Departments of Neurological Surgery and Physical Therapy and Rehabilitation Science, University of California, San Francisco, San Francisco, CA, 94110, USA
| | - Mitchell S Turker
- Oregon Institute of Occupational Health Sciences and Department of Molecular and Medical Genetics, Oregon Health and Science University, Portland, OR, 97239, USA
| | - Jacob Raber
- Department of Behavioral Neuroscience, Oregon Health and Science University, Portland, OR, 97239, USA. .,Departments of Neurology and Radiation Medicine, Division of Neuroscience ONPRC, Oregon Health and Science University, Portland, OR, 97239, USA.
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Impey S, Jopson T, Pelz C, Tafessu A, Fareh F, Zuloaga D, Marzulla T, Riparip LK, Stewart B, Rosi S, Turker MS, Raber J. Short- and long-term effects of 56Fe irradiation on cognition and hippocampal DNA methylation and gene expression. BMC Genomics 2016; 17:825. [PMID: 27776477 PMCID: PMC5078898 DOI: 10.1186/s12864-016-3110-7] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2016] [Accepted: 09/22/2016] [Indexed: 12/21/2022] Open
Abstract
Background Astronauts are exposed to 56Fe ions that may pose a significant health hazard during and following prolonged missions in deep space. We showed previously that object recognition requiring the hippocampus, a structure critical for cognitive function, is affected in 2-month-old mice irradiated with 56Fe ions. Here we examined object recognition in 6-month-old mice irradiated with 56Fe ions, a biological age more relevant to the typical ages of astronauts. Moreover, because the mechanisms mediating the detrimental effects of 56Fe ions on hippocampal function are unclear, we examined changes in hippocampal networks involved in synaptic plasticity and memory, gene expression, and epigenetic changes in cytosine methylation (5mC) and hydroxymethylation (5hmC) that could accompany changes in gene expression. We assessed the effects of whole body 56Fe ion irradiation at early (2 weeks) and late (20 weeks) time points on hippocampus-dependent memory and hippocampal network stability, and whether these effects are associated with epigenetic changes in hippocampal DNA methylation (both 5mC and 5hmC) and gene expression. Results At the two-week time point, object recognition and network stability were impaired following irradiation at the 0.1 and 0.4 Gy dose, but not following irradiation at the 0.2 Gy dose. No impairments in object recognition or network stability were seen at the 20-week time point at any irradiation dose used. Consistent with this pattern, the significance of pathways for gene categories for 5hmC was lower, though not eliminated, at the 20-week time point compared to the 2-week time point. Similarly, significant changes were observed for 5mC gene pathways at the 2-week time point, but no significant gene categories were observed at the 20-week time point. Only the 5hmC changes tracked with gene expression changes. Conclusions Dose- and time-dependent epigenomic remodeling in the hippocampus following 56Fe ion exposure correlates with behavioral changes. Electronic supplementary material The online version of this article (doi:10.1186/s12864-016-3110-7) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Soren Impey
- Oregon Stem Cell Center and Department of Pediatrics, Oregon Health and Science University, Portland, OR, 97239, USA. .,Department of Cell, Developmental Biology, and Cancer Biology, Oregon Health and Science University, Portland, OR, 97239, USA.
| | - Timothy Jopson
- Brain and Spinal Injury Center, University of California, San Francisco, San Francisco, CA, 94110, USA.,Departments of Physical Therapy Rehabilitation Science, University of California, San Francisco, San Francisco, CA, 94110, USA.,Neurological Surgery, University of California San Francisco, Zuckerberg San Francisco General Hospital, San Francisco, CA, 94110, USA
| | - Carl Pelz
- Oregon Stem Cell Center and Department of Pediatrics, Oregon Health and Science University, Portland, OR, 97239, USA
| | - Amanuel Tafessu
- Oregon Stem Cell Center and Department of Pediatrics, Oregon Health and Science University, Portland, OR, 97239, USA
| | - Fatema Fareh
- Oregon Stem Cell Center and Department of Pediatrics, Oregon Health and Science University, Portland, OR, 97239, USA
| | - Damian Zuloaga
- Department of Behavioral Neuroscience, Oregon Health and Science University, Portland, OR, 97239, USA
| | - Tessa Marzulla
- Department of Behavioral Neuroscience, Oregon Health and Science University, Portland, OR, 97239, USA
| | - Lara-Kirstie Riparip
- Brain and Spinal Injury Center, University of California, San Francisco, San Francisco, CA, 94110, USA.,Departments of Physical Therapy Rehabilitation Science, University of California, San Francisco, San Francisco, CA, 94110, USA.,Neurological Surgery, University of California San Francisco, Zuckerberg San Francisco General Hospital, San Francisco, CA, 94110, USA
| | - Blair Stewart
- Department of Behavioral Neuroscience, Oregon Health and Science University, Portland, OR, 97239, USA
| | - Susanna Rosi
- Brain and Spinal Injury Center, University of California, San Francisco, San Francisco, CA, 94110, USA.,Departments of Physical Therapy Rehabilitation Science, University of California, San Francisco, San Francisco, CA, 94110, USA.,Neurological Surgery, University of California San Francisco, Zuckerberg San Francisco General Hospital, San Francisco, CA, 94110, USA
| | - Mitchell S Turker
- Oregon Institute of Occupational Health Sciences and Department of Molecular and Medical Genetics, Oregon Health and Science University, Portland, OR, 97239, USA
| | - Jacob Raber
- Department of Behavioral Neuroscience, Oregon Health and Science University, Portland, OR, 97239, USA. .,Departments of Neurology and Radiation Medicine, Oregon Health and Science University, Portland, OR, 97239, USA. .,Division of Neuroscience ONPRC, Oregon Health and Science University, Portland, OR, 97239, USA.
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Possible involvement of hippocampal immediate–early genes in contextual fear memory deficit induced by cranial irradiation. Neurobiol Learn Mem 2016; 133:19-29. [DOI: 10.1016/j.nlm.2016.05.012] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2015] [Revised: 05/23/2016] [Accepted: 05/28/2016] [Indexed: 12/20/2022]
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10
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Huang L, Wickramasekara SI, Akinyeke T, Stewart BS, Jiang Y, Raber J, Maier CS. Ion mobility-enhanced MS(E)-based label-free analysis reveals effects of low-dose radiation post contextual fear conditioning training on the mouse hippocampal proteome. J Proteomics 2016; 140:24-36. [PMID: 27020882 PMCID: PMC5029422 DOI: 10.1016/j.jprot.2016.03.032] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2015] [Revised: 03/16/2016] [Accepted: 03/17/2016] [Indexed: 11/15/2022]
Abstract
UNLABELLED Recent advances in the field of biodosimetry have shown that the response of biological systems to ionizing radiation is complex and depends on the type and dose of radiation, the tissue(s) exposed, and the time lapsed after exposure. The biological effects of low dose radiation on learning and memory are not well understood. An ion mobility-enhanced data-independent acquisition (MS(E)) approach in conjunction with the ISOQuant software tool was utilized for label-free quantification of hippocampal proteins with the goal of determining protein alteration associated with low-dose whole body ionizing radiation (X-rays, 1Gy) of 5.5-month-old male C57BL/6J mice post contextual fear conditioning training. Global proteome analysis revealed deregulation of 73 proteins (out of 399 proteins). Deregulated proteins indicated adverse effects of irradiation on myelination and perturbation of energy metabolism pathways involving a shift from the TCA cycle to glutamate oxidation. Our findings also indicate that proteins associated with synaptic activity, including vesicle recycling and neurotransmission, were altered in the irradiated mice. The elevated LTP and decreased LTD suggest improved synaptic transmission and enhanced efficiency of neurotransmitter release which would be consistent with the observed comparable contextual fear memory performance of the mice following post-training whole body or sham-irradiation. SIGNIFICANCE This study is significant because the biological consequences of low dose radiation on learning and memory are complex and not yet well understood. We conducted a IMS-enhanced MS(E)-based label-free quantitative proteomic analysis of hippocampal tissue with the goal of determining protein alteration associated with low-dose whole body ionizing radiation (X-ray, 1Gy) of 5.5-month-old male C57BL/6J mice post contextual fear conditioning training. The IMS-enhanced MS(E) approach in conjunction with ISOQuant software was robust and accurate with low median CV values of 0.99% for the technical replicates of samples from both the sham and irradiated group. The biological variance was as low as 1.61% for the sham group and 1.31% for the irradiated group. The applied data generation and processing workflow allowed the quantitative evaluation of 399 proteins. The current proteomic analysis indicates that myelination is sensitive to low dose radiation. The observed protein level changes imply modulation of energy metabolism pathways in the radiation exposed group, specifically changes in protein abundance levels suggest a shift from TCA cycle to glutamate oxidation to satisfy energy demands. Most significantly, our study reveals deregulation of proteins involved in processes that govern synaptic activity including enhanced synaptic vesicle cycling, and altered long-term potentiation (LTP) and depression (LTD). An elevated LTP and decreased LTD suggest improved synaptic transmission and enhanced efficiency of neurotransmitter release which is consistent with the observed comparable contextual fear memory performance of the mice following post-training whole body or sham-irradiation. Overall, our results underscore the importance of low dose radiation experiments for illuminating the sensitivity of biochemical pathways to radiation, and the modulation of potential repair and compensatory response mechanisms. This kind of studies and associated findings may ultimately lead to the design of strategies for ameliorating hippocampal and CNS injury following radiation exposure as part of medical therapies or as a consequence of occupational hazards.
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Affiliation(s)
- Lin Huang
- Department of Chemistry, Oregon State University, Corvallis, Oregon 97331, United States
| | | | - Tunde Akinyeke
- Department of Behavioral Neuroscience, Division of Neuroscience, ONPRC, Oregon Health and Science University, Portland, Oregon 97239, United States
| | - Blair S Stewart
- Department of Behavioral Neuroscience, Division of Neuroscience, ONPRC, Oregon Health and Science University, Portland, Oregon 97239, United States
| | - Yuan Jiang
- Department of Statistics, Oregon State University, Corvallis, Oregon 97331, United States
| | - Jacob Raber
- Department of Behavioral Neuroscience, Division of Neuroscience, ONPRC, Oregon Health and Science University, Portland, Oregon 97239, United States; Departments of Neurology and Radiation Medicine, Division of Neuroscience, ONPRC, Oregon Health and Science University, Portland, Oregon 97239, United States
| | - Claudia S Maier
- Department of Chemistry, Oregon State University, Corvallis, Oregon 97331, United States.
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Raber J, Allen AR, Weber S, Chakraborti A, Sharma S, Fike JR. Effect of behavioral testing on spine density of basal dendrites in the CA1 region of the hippocampus modulated by (56)Fe irradiation. Behav Brain Res 2016; 302:263-8. [PMID: 26801826 DOI: 10.1016/j.bbr.2016.01.035] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Revised: 01/13/2016] [Accepted: 01/16/2016] [Indexed: 01/11/2023]
Abstract
A unique feature of the space radiation environment is the presence of high-energy charged particles, including (56)Fe ions, which can present a significant hazard to space flight crews during and following a mission. (56)Fe irradiation-induced cognitive changes often involve alterations in hippocampal function. These alterations might involve changes in spine morphology and density. In addition to irradiation, performing a cognitive task can also affect spine morphology. Therefore, it is often hard to determine whether changes in spine morphology and density are due to an environmental challenge or group differences in performance on cognitive tests. In this study, we tested the hypothesis that the ability of exploratory behavior to increase specific measures of hippocampal spine morphology and density is affected by (56)Fe irradiation. In sham-irradiated mice, exploratory behavior increased basal spine density in the CA1 region of the hippocampus and the enclosed blade of the dentate gyrus. These effects were not seen in irradiated mice. In addition, following exploratory behavior, there was a trend toward a decrease in the percent stubby spines on apical dendrites in the CA3 region of the hippocampus in (56)Fe-irradiated, but not sham-irradiated, mice. Other hippocampal regions and spine measures affected by (56)Fe irradiation showed comparable radiation effects in behaviorally naïve and cognitively tested mice. Thus, the ability of exploratory behavior to alter spine density and morphology in specific hippocampal regions is affected by (56)Fe irradiation.
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Affiliation(s)
- Jacob Raber
- Department of Behavioral Neuroscience, ONPRC, Oregon Health and Science University, Portland, OR 97239, United States; Departments of Neurology, Radiation Medicine and Division of Neuroscience, ONPRC, Oregon Health and Science University, Portland, OR 97239, United States.
| | - Antiño R Allen
- Division of Radiation Health, Department of Pharmaceutical Sciences, University of Arkansas for Medical Sciences, Little Rock, AR 72205, United States
| | - Sydney Weber
- Department of Behavioral Neuroscience, ONPRC, Oregon Health and Science University, Portland, OR 97239, United States
| | - Ayanabha Chakraborti
- Brain and Spinal Injury Center, Department of Neurological Surgery, University of California, San Francisco, CA 94110, United States; The Brain Research Institute at Monash Sunway, Selangor Darul Ehsan, Malaysia
| | - Sourabh Sharma
- Departments of Neurology, Radiation Medicine and Division of Neuroscience, ONPRC, Oregon Health and Science University, Portland, OR 97239, United States
| | - John R Fike
- Departments of Neurology, Radiation Medicine and Division of Neuroscience, ONPRC, Oregon Health and Science University, Portland, OR 97239, United States; Department of Radiation Oncology, University of California, San Francisco, CA 94110, United States
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Raber J, Allen AR, Sharma S, Allen B, Rosi S, Olsen RHJ, Davis MJ, Eiwaz M, Fike JR, Nelson GA. Effects of Proton and Combined Proton and 56Fe Radiation on the Hippocampus. Radiat Res 2015; 185:20-30. [DOI: 10.1667/rr14222.1] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
| | - Antiño R. Allen
- Brain and Spinal Injury Center, Department of Neurological Surgery,
| | - Sourabh Sharma
- Brain and Spinal Injury Center, Department of Neurological Surgery,
| | - Barrett Allen
- Brain and Spinal Injury Center, Department of Neurological Surgery,
| | - Susanna Rosi
- Brain and Spinal Injury Center, Department of Neurological Surgery,
| | | | | | | | - John R. Fike
- Brain and Spinal Injury Center, Department of Neurological Surgery,
| | - Gregory A. Nelson
- Department of Basic Sciences, Division of Radiation Research, Loma Linda University, Loma Linda, California, 92350
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Allen AR, Raber J, Chakraborti A, Sharma S, Fike JR. 56Fe Irradiation Alters Spine Density and Dendritic Complexity in the Mouse Hippocampus. Radiat Res 2015; 184:586-94. [DOI: 10.1667/rr14103.1] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Tomé WA, Gökhan Ş, Gulinello ME, Brodin NP, Heard J, Mehler MF, Guha C. Hippocampal-dependent neurocognitive impairment following cranial irradiation observed in pre-clinical models: current knowledge and possible future directions. Br J Radiol 2015; 89:20150762. [PMID: 26514377 DOI: 10.1259/bjr.20150762] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
We reviewed the literature for studies pertaining to impaired adult neurogenesis leading to neurocognitive impairment following cranial irradiation in rodent models. This compendium was compared with respect to radiation dose, converted to equivalent dose in 2 Gy fractions (EQD2) to allow for direct comparison between studies. The effects of differences between animal species and the dependence on animal age as well as for time after irradiation were also considered. One of the major sites of de novo adult neurogenesis is the hippocampus, and as such, this review also focuses on assessing evidence related to the expression and potential effects of inflammatory cytokines on neural stem cells in the subgranular zone of the dentate gyrus and whether this correlates with neurocognitive impairment. This review also discusses potential strategies to mitigate the detrimental effects on neurogenesis and neurocognition resulting from cranial irradiation, and how the rationale for these strategies compares with the current outcome of pre-clinical studies.
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Affiliation(s)
- Wolfgang A Tomé
- 1 Institute for Onco-Physics, Department of Radiation Oncology, Albert Einstein College of Medicine, Bronx, NY, USA.,2 Department of Radiation Oncology, Montefiore Medical Center, Bronx, NY, USA.,3 Department of Neurology, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Şölen Gökhan
- 3 Department of Neurology, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Maria E Gulinello
- 4 Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY, USA
| | - N Patrik Brodin
- 1 Institute for Onco-Physics, Department of Radiation Oncology, Albert Einstein College of Medicine, Bronx, NY, USA.,2 Department of Radiation Oncology, Montefiore Medical Center, Bronx, NY, USA
| | - John Heard
- 2 Department of Radiation Oncology, Montefiore Medical Center, Bronx, NY, USA
| | - Mark F Mehler
- 3 Department of Neurology, Albert Einstein College of Medicine, Bronx, NY, USA.,4 Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY, USA.,5 Department of Psychiatry and Behavioral Sciences, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Chandan Guha
- 1 Institute for Onco-Physics, Department of Radiation Oncology, Albert Einstein College of Medicine, Bronx, NY, USA.,2 Department of Radiation Oncology, Montefiore Medical Center, Bronx, NY, USA
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Marty VN, Vlkolinsky R, Minassian N, Cohen T, Nelson GA, Spigelman I. Radiation-Induced Alterations in Synaptic Neurotransmission of Dentate Granule Cells Depend on the Dose and Species of Charged Particles. Radiat Res 2014; 182:653-65. [DOI: 10.1667/rr13647.1] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Olsen RHJ, Marzulla T, Raber J. Impairment in extinction of contextual and cued fear following post-training whole-body irradiation. Front Behav Neurosci 2014; 8:231. [PMID: 25071488 PMCID: PMC4078460 DOI: 10.3389/fnbeh.2014.00231] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2014] [Accepted: 06/07/2014] [Indexed: 12/30/2022] Open
Abstract
Because of the use of radiation in cancer therapy, the risk of nuclear contamination from power plants, military conflicts, and terrorism, there is a compelling scientific and public health interest in the effects of environmental radiation exposure on brain function, in particular hippocampal function and learning and memory. Previous studies have emphasized changes in learning and memory following radiation exposure. These approaches have ignored the question of how radiation exposure might impact recently acquired memories, which might be acquired under traumatic circumstances (cancer treatment, nuclear disaster, etc.). To address the question of how radiation exposure might affect the processing and recall of recently acquired memories, we employed a fear conditioning paradigm wherein animals were trained, and subsequently irradiated (whole-body X-ray irradiation) 24 h later. Animals were given 2 weeks to recover, and were tested for retention and extinction of hippocampus-dependent contextual fear conditioning or hippocampus-independent cued fear conditioning. Exposure to irradiation following training was associated with reduced daily increases in body weights over the 22-days of the study and resulted in greater freezing levels and aberrant extinction 2 weeks later. This was also observed when the intensity of the training protocol was increased. Cued freezing levels and measures of anxiety 2 weeks after training were also higher in irradiated than sham-irradiated mice. In contrast to contextual freezing levels, cued freezing levels were even higher in irradiated mice receiving 5 shocks during training than sham-irradiated mice receiving 10 shocks during training. In addition, the effects of radiation on extinction of contextual fear were more profound than those on the extinction of cued fear. Thus, whole-body irradiation elevates contextual and cued fear memory recall.
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Affiliation(s)
- Reid H J Olsen
- Department of Behavioral Neuroscience, Oregon Health and Science University , Portland, OR , USA
| | - Tessa Marzulla
- Department of Behavioral Neuroscience, Oregon Health and Science University , Portland, OR , USA
| | - Jacob Raber
- Department of Behavioral Neuroscience, Oregon Health and Science University , Portland, OR , USA ; Division of Neuroscience, Oregon National Primate Research Center, Oregon Health and Science University , Portland, OR , USA ; Department of Neurology, Oregon Health and Science University , Portland, OR , USA ; Department of Radiation Medicine, Oregon Health and Science University , Portland, OR , USA
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Sweet TB, Panda N, Hein AM, Das SL, Hurley SD, Olschowka JA, Williams JP, O'Banion MK. Central Nervous System Effects of Whole-Body Proton Irradiation. Radiat Res 2014; 182:18-34. [DOI: 10.1667/rr13699.1] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Tara Beth Sweet
- Department of Neurobiology and Anatomy, University of Rochester School of Medicine and Dentistry, Rochester, New York 14642
| | - Nirlipta Panda
- Department of Neurobiology and Anatomy, University of Rochester School of Medicine and Dentistry, Rochester, New York 14642
| | - Amy M. Hein
- Department of Neurobiology and Anatomy, University of Rochester School of Medicine and Dentistry, Rochester, New York 14642
| | - Shoshana L. Das
- Department of Neurobiology and Anatomy, University of Rochester School of Medicine and Dentistry, Rochester, New York 14642
| | - Sean D. Hurley
- Department of Neurobiology and Anatomy, University of Rochester School of Medicine and Dentistry, Rochester, New York 14642
| | - John A. Olschowka
- Department of Neurobiology and Anatomy, University of Rochester School of Medicine and Dentistry, Rochester, New York 14642
| | - Jacqueline P. Williams
- Department of Environmental Medicine, University of Rochester School of Medicine and Dentistry, Rochester, New York 14642
| | - M. Kerry O'Banion
- Department of Neurobiology and Anatomy, University of Rochester School of Medicine and Dentistry, Rochester, New York 14642
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Rabin BM, Shukitt-Hale B, Carrihill-Knoll KL, Gomes SM. Comparison of the Effects of Partial- or Whole-Body Exposures to16O Particles on Cognitive Performance in Rats. Radiat Res 2014; 181:251-7. [DOI: 10.1667/rr13469.1] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Rabin BM, Shukitt-Hale B, Carrihill-Knoll KL. Effects of Age on the Disruption of Cognitive Performance by Exposure to Space Radiation. ACTA ACUST UNITED AC 2014. [DOI: 10.4236/jbbs.2014.47031] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Villasana L, Dayger C, Raber J. Dose- and ApoE Isoform-Dependent Cognitive Injury after Cranial56Fe Irradiation in Female Mice. Radiat Res 2013; 179:493-500. [DOI: 10.1667/rr3210.1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Abstract
The complex charged particle environments in space pose considerable challenges with regard to potential health consequences that can impact mission design and crew selection. The lack of knowledge of the biological effects of different ions in isolation and in combination is a particular concern because the risk uncertainties are very high for both cancer and non-cancer late effects. Reducing the uncertainties is of high priority. Two principal components of space radiation each raise different concerns. Solar particle events (SPE) occur sporadically and are comprised primarily of low- to moderate-energy protons. Galactic cosmic radiation (GCR) is isotropic and relatively invariant in dose rate. GCR is also dominated by protons, but the energy range is wider than in SPE. In addition, the contribution of other light and heavy ions to the health risks from GCR must be addressed. This paper will introduce the principal issues under consideration for space radiation protection.
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Affiliation(s)
- Amy Kronenberg
- Life Sciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720, USA.
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Haley GE, Villasana L, Dayger C, Davis MJ, Raber J. Apolipoprotein e genotype-dependent paradoxical short-term effects of (56)fe irradiation on the brain. Int J Radiat Oncol Biol Phys 2012; 84:793-9. [PMID: 22401921 DOI: 10.1016/j.ijrobp.2011.12.049] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2011] [Revised: 12/07/2011] [Accepted: 12/12/2011] [Indexed: 10/28/2022]
Abstract
PURPOSE In humans, apolipoprotein E (apoE) is encoded by three major alleles (ε2, ε3, and ε4) and, compared to apoE3, apoE4 increases the risk of developing Alzheimer disease and cognitive impairments following various environmental challenges. Exposure to irradiation, including that of (56)Fe, during space missions poses a significant risk to the central nervous system, and apoE isoform might modulate this risk. METHODS AND MATERIALS We investigated whether apoE isoform modulates hippocampus-dependent cognitive performance starting 2 weeks after (56)Fe irradiation. Changes in reactive oxygen species (ROS) can affect cognition and are induced by irradiation. Therefore, after cognitive testing, we assessed hippocampal ROS levels in ex vivo brain slices, using the ROS-sensitive fluorescent probe, dihydroethidium (DHE). Brain levels of 3-nitrotyrosine (3-NT), CuZn superoxide dismutase (CuZnSOD), extracellular SOD, and apoE were assessed using Western blotting analysis. RESULTS In the water maze, spatial memory retention was impaired by irradiation in apoE2 and apoE4 mice but enhanced by irradiation in apoE3 mice. Irradiation reduced DHE-oxidation levels in the enclosed blade of the dentate gyrus and levels of 3-NT and CuZnSOD in apoE2 but not apoE3 or apoE4 mice. Finally, irradiation increased apoE levels in apoE3 but not apoE2 or apoE4 mice. CONCLUSIONS The short-term effects of (56)Fe irradiation on hippocampal ROS levels and hippocampus-dependent spatial memory retention are apoE isoform-dependent.
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Affiliation(s)
- Gwendolen E Haley
- Department of Behavioral Neuroscience, Oregon Health and Science University, Portland, OR 97239, USA
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