1
|
Amelchenko EM, Bezriadnov DV, Chekhov OA, Ivanova AA, Kedrov AV, Anokhin KV, Lazutkin AA, Enikolopov G. Cognitive Flexibility Is Selectively Impaired by Radiation and Is Associated with Differential Recruitment of Adult-Born Neurons. J Neurosci 2023; 43:6061-6083. [PMID: 37532464 PMCID: PMC10451007 DOI: 10.1523/jneurosci.0161-22.2023] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Revised: 06/17/2023] [Accepted: 06/23/2023] [Indexed: 08/04/2023] Open
Abstract
Exposure to elevated doses of ionizing radiation, such as those in therapeutic procedures, catastrophic accidents, or space exploration, increases the risk of cognitive dysfunction. The full range of radiation-induced cognitive deficits is unknown, partly because commonly used tests may be insufficiently sensitive or may not be adequately tuned for assessing the fine behavioral features affected by radiation. Here, we asked whether γ-radiation might affect learning, memory, and the overall ability to adapt behavior to cope with a challenging environment (cognitive/behavioral flexibility). We developed a new behavioral assay, the context discrimination Morris water maze (cdMWM) task, which is hippocampus-dependent and requires the integration of various contextual cues and the adjustment of search strategies. We exposed male mice to 1 or 5 Gy of γ rays and, at different time points after irradiation, trained them consecutively in spatial MWM, reversal MWM, and cdMWM tasks, and assessed their learning, navigational search strategies, and memory. Mice exposed to 5 Gy performed successfully in the spatial and reversal MWM tasks; however, in the cdMWM task 6 or 8 weeks (but not 3 weeks) after irradiation, they demonstrated transient learning deficit, decreased use of efficient spatially precise search strategies during learning, and, 6 weeks after irradiation, memory deficit. We also observed impaired neurogenesis after irradiation and selective activation of 12-week-old newborn neurons by specific components of cdMWM training paradigm. Thus, our new behavioral paradigm reveals the effects of γ-radiation on cognitive flexibility and indicates an extended timeframe for the functional maturation of new hippocampal neurons.SIGNIFICANCE STATEMENT Exposure to radiation can affect cognitive performance and cognitive flexibility - the ability to adapt to changed circumstances and demands. The full range of consequences of irradiation on cognitive flexibility is unknown, partly because of a lack of suitable models. Here, we developed a new behavioral task requiring mice to combine various types of cues and strategies to find a correct solution. We show that animals exposed to γ-radiation, despite being able to successfully solve standard problems, show delayed learning, deficient memory, and diminished use of efficient navigation patterns in circumstances requiring adjustments of previously used search strategies. This new task could be applied in other settings for assessing the cognitive changes induced by aging, trauma, or disease.
Collapse
Affiliation(s)
- Evgeny M Amelchenko
- Center for Developmental Genetics
- Department of Anesthesiology, Stony Brook University, Stony Brook, New York 11794
| | - Dmitri V Bezriadnov
- P.K. Anokhin Research Institute of Normal Physiology, Moscow, 125315, Russian Federation
| | - Olga A Chekhov
- Center for Developmental Genetics
- Department of Anesthesiology, Stony Brook University, Stony Brook, New York 11794
| | - Anna A Ivanova
- Institute of Higher Nervous Activity and Neurophysiology RAS, Moscow, 117485, Russian Federation
- Institute for Advanced Brain Studies, Lomonosov Moscow State University, Moscow, 119234, Russian Federation
| | - Alexander V Kedrov
- P.K. Anokhin Research Institute of Normal Physiology, Moscow, 125315, Russian Federation
| | - Konstantin V Anokhin
- P.K. Anokhin Research Institute of Normal Physiology, Moscow, 125315, Russian Federation
- Institute for Advanced Brain Studies, Lomonosov Moscow State University, Moscow, 119234, Russian Federation
| | - Alexander A Lazutkin
- Center for Developmental Genetics
- Department of Anesthesiology, Stony Brook University, Stony Brook, New York 11794
- Institute of Higher Nervous Activity and Neurophysiology RAS, Moscow, 117485, Russian Federation
| | - Grigori Enikolopov
- Center for Developmental Genetics
- Department of Anesthesiology, Stony Brook University, Stony Brook, New York 11794
| |
Collapse
|
2
|
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.
Collapse
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.
| |
Collapse
|
3
|
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.
Collapse
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
| |
Collapse
|
4
|
Willey JS, Britten RA, Blaber E, Tahimic CG, Chancellor J, Mortreux M, Sanford LD, Kubik AJ, Delp MD, Mao XW. The individual and combined effects of spaceflight radiation and microgravity on biologic systems and functional outcomes. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART C, TOXICOLOGY AND CARCINOGENESIS 2021; 39:129-179. [PMID: 33902391 PMCID: PMC8274610 DOI: 10.1080/26896583.2021.1885283] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Both microgravity and radiation exposure in the spaceflight environment have been identified as hazards to astronaut health and performance. Substantial study has been focused on understanding the biology and risks associated with prolonged exposure to microgravity, and the hazards presented by radiation from galactic cosmic rays (GCR) and solar particle events (SPEs) outside of low earth orbit (LEO). To date, the majority of the ground-based analogues (e.g., rodent or cell culture studies) that investigate the biology of and risks associated with spaceflight hazards will focus on an individual hazard in isolation. However, astronauts will face these challenges simultaneously Combined hazard studies are necessary for understanding the risks astronauts face as they travel outside of LEO, and are also critical for countermeasure development. The focus of this review is to describe biologic and functional outcomes from ground-based analogue models for microgravity and radiation, specifically highlighting the combined effects of radiation and reduced weight-bearing from rodent ground-based tail suspension via hind limb unloading (HLU) and partial weight-bearing (PWB) models, although in vitro and spaceflight results are discussed as appropriate. The review focuses on the skeletal, ocular, central nervous system (CNS), cardiovascular, and stem cells responses.
Collapse
Affiliation(s)
| | | | - Elizabeth Blaber
- Department of Biomedical Engineering, Rensselaer Polytechnic Institute
| | | | | | - Marie Mortreux
- Department of Neurology, Harvard Medical School, Beth Israel Deaconess Medical Center
| | - Larry D. Sanford
- Department of Radiation Oncology, Eastern Virginia Medical School
| | - Angela J. Kubik
- Department of Biomedical Engineering, Rensselaer Polytechnic Institute
| | - Michael D. Delp
- Department of Nutrition, Food and Exercise Sciences, Florida State University
| | - Xiao Wen Mao
- Division of Biomedical Engineering Sciences (BMES), Department of Basic Sciences, Loma Linda University
| |
Collapse
|
5
|
Communication, Cross Talk, and Signal Integration in the Adult Hippocampal Neurogenic Niche. Neuron 2020; 105:220-235. [PMID: 31972145 DOI: 10.1016/j.neuron.2019.11.029] [Citation(s) in RCA: 65] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Revised: 11/21/2019] [Accepted: 11/25/2019] [Indexed: 12/14/2022]
Abstract
Radial glia-like neural stem cells (RGLs) in the dentate gyrus subregion of the hippocampus give rise to dentate granule cells (DGCs) and astrocytes throughout life, a process referred to as adult hippocampal neurogenesis. Adult hippocampal neurogenesis is sensitive to experiences, suggesting that it may represent an adaptive mechanism by which hippocampal circuitry is modified in response to environmental demands. Experiential information is conveyed to RGLs, progenitors, and adult-born DGCs via the neurogenic niche that is composed of diverse cell types, extracellular matrix, and afferents. Understanding how the niche performs its functions may guide strategies to maintain its health span and provide a permissive milieu for neurogenesis. Here, we first discuss representative contributions of niche cell types to regulation of neural stem cell (NSC) homeostasis and maturation of adult-born DGCs. We then consider mechanisms by which the activity of multiple niche cell types may be coordinated to communicate signals to NSCs. Finally, we speculate how NSCs integrate niche-derived signals to govern their regulation.
Collapse
|
6
|
Yokota Y, Wada Y, Funayama T. Distinct modes of death in human neural stem and glioblastoma cells irradiated with carbon-ion radiation and gamma-rays. Int J Radiat Biol 2019; 96:172-178. [PMID: 31633435 DOI: 10.1080/09553002.2020.1683639] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Purpose: Accumulated damage in neural stem cells (NSCs) during brain tumor radiotherapy causes cognitive dysfunction to the patients. Carbon-ion radiotherapy can reduce undesired irradiation of normal tissues more efficiently than conventional photon radiotherapy. This study elucidates the responses of NSCs to carbon-ion radiation.Methods: Human NSCs and glioblastoma A-172 cells were irradiated with carbon-ion radiation and γ-rays, which have different linear-energy-transfer (LET) values of 108 and 0.2 keV/μm, respectively. After irradiation, growth rates were measured, apoptotic cells were detected by flow cytometry, and DNA synthesizing cells were immunocytochemically visualized.Results: Growth rates of NSCs and A-172 cells were decreased after irradiation. The percentages of apoptotic cells were remarkably increased in NSCs but not in A-172 cells. In contrast, the fractions of DNA synthesizing A-172 cells were decreased in a dose-dependent manner. These results indicate that apoptosis induction and DNA synthesis inhibition contribute to the growth inhibition of NSCs and glioblastoma cells, respectively. In addition, high-LET carbon ions induced more profound effects than low-LET γ-rays.Conclusions: Apoptosis is an important clinical target to protect NSCs during brain tumor radiotherapy using carbon-ion radiation as well as conventional X-rays.
Collapse
Affiliation(s)
- Yuichiro Yokota
- Department of Radiation-Applied Biology Research, Takasaki Advanced Radiation Research Institute, National Institutes for Quantum and Radiological Science and Technology, Takasaki, Japan
| | - Yutaka Wada
- Department of Radiation-Applied Biology Research, Takasaki Advanced Radiation Research Institute, National Institutes for Quantum and Radiological Science and Technology, Takasaki, Japan
| | - Tomoo Funayama
- Department of Radiation-Applied Biology Research, Takasaki Advanced Radiation Research Institute, National Institutes for Quantum and Radiological Science and Technology, Takasaki, Japan
| |
Collapse
|
7
|
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: 23] [Impact Index Per Article: 4.6] [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.
Collapse
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
| |
Collapse
|
8
|
Heterogeneity of Stem Cells in the Hippocampus. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1169:31-53. [DOI: 10.1007/978-3-030-24108-7_2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
|
9
|
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.
Collapse
|
10
|
Zonis S, Breunig JJ, Mamelak A, Wawrowsky K, Bresee C, Ginzburg N, Chesnokova V. Inflammation-induced Gro1 triggers senescence in neuronal progenitors: effects of estradiol. J Neuroinflammation 2018; 15:260. [PMID: 30201019 PMCID: PMC6131894 DOI: 10.1186/s12974-018-1298-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Accepted: 08/29/2018] [Indexed: 02/02/2023] Open
Abstract
BACKGROUND Inflammation has been proposed to contribute to the decline in adult hippocampal neurogenesis. Proinflammatory cytokines activate transcription of chemokine growth-regulated oncogene α (Gro1) in human and murine hippocampal neuronal progenitor cells (NPC). The goal of this study was to investigate the effects of Gro1 on hippocampal neurogenesis in the presence of inflammation. METHODS Human hippocampal NPC were transfected with lentivirus expressing Gro1, and murine NPC and hippocampal neuronal HT-22 cells were treated with Gro1 protein. A plasmid expressing mGro1 was electroporated in the hippocampus of newborn mice that were sacrificed 10 days later. Adult male and female mice were injected with lipopolysaccharide (LPS; 1 mg/kg, i.p in five daily injections) or normal saline. Adult male mice were implanted with pellets releasing 17-β estradiol (E2; 2.5 mg/pellet, 41.666 μg/day release) or placebo for 6 weeks and challenged with LPS or normal saline as above. In both experiments, mice were sacrificed 3 h after the last injection. Hippocampal markers of neurogenesis were assessed in vitro and in vivo by Western blot, real-time PCR, and immunohisto/cytochemistry. RESULTS Gro1 induced premature senescence in NPC and HT-22 cells, activating senescence-associated β-galactosidase and the cell cycle inhibitor p16 and suppressing neuroblast proliferation and expression of doublecortin (DCX) and neuron-specific class III beta-tubulin (Tuj-1), both neuroblast markers, while promoting proliferation of neural glial antigen 2 (Ng2)-positive oligodendrocytes. Gro1 overexpression in the hippocampus of newborn mice resulted in decreased neuroblast development, as evidenced by decreased DCX expression and increased expression of platelet-derived growth factor α receptor (PDGFαR), a marker of oligodendrocyte precursors. In adult mice, Gro1 was induced in response to LPS treatment in male but not in female hippocampus, with a subsequent decrease in neurogenesis and activation of oligodendrocyte progenitors. No changes in neurogenesis were observed in females. Treatment with E2 blunted LPS-induced Gro1 in the male hippocampus. CONCLUSIONS Inflammation-induced Gro1 triggers neuroblast senescence, thus suppressing new neuron development in the hippocampus. Sex-dependent differences in Gro1 response are attributed to estradiol, which blunts these changes, protecting the female hippocampus from the deleterious effects of inflammation-induced Gro1 on neurogenesis.
Collapse
Affiliation(s)
- Svetlana Zonis
- Pituitary Center, Department of Medicine, Cedars-Sinai Medical Center, 8700 Beverly Blvd., Los Angeles, CA 90048 USA
| | - Joshua J. Breunig
- Department of Neurosurgery, Cedars-Sinai Medical Center, 8700 Beverly Blvd., Los Angeles, CA 90048 USA
| | - Adam Mamelak
- Pituitary Center, Department of Medicine, Cedars-Sinai Medical Center, 8700 Beverly Blvd., Los Angeles, CA 90048 USA
- Department of Neurosurgery, Cedars-Sinai Medical Center, 8700 Beverly Blvd., Los Angeles, CA 90048 USA
| | - Kolja Wawrowsky
- Department of Biomedical Science, Cedars-Sinai Medical Center, 8700 Beverly Blvd., Los Angeles, CA 90048 USA
| | - Catherine Bresee
- Biostatistics and Bioinformatics Core, Cedars-Sinai Medical Center, 8700 Beverly Blvd., Los Angeles, CA 90048 USA
| | - Nadiya Ginzburg
- Pituitary Center, Department of Medicine, Cedars-Sinai Medical Center, 8700 Beverly Blvd., Los Angeles, CA 90048 USA
| | - Vera Chesnokova
- Pituitary Center, Department of Medicine, Cedars-Sinai Medical Center, 8700 Beverly Blvd., Los Angeles, CA 90048 USA
| |
Collapse
|
11
|
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.
Collapse
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
| |
Collapse
|
12
|
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.
Collapse
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
| |
Collapse
|
13
|
VEGF preconditioning leads to stem cell remodeling and attenuates age-related decay of adult hippocampal neurogenesis. Proc Natl Acad Sci U S A 2016; 113:E7828-E7836. [PMID: 27849577 DOI: 10.1073/pnas.1609592113] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Several factors are known to enhance adult hippocampal neurogenesis but a factor capable of inducing a long-lasting neurogenic enhancement that attenuates age-related neurogenic decay has not been described. Here, we studied hippocampal neurogenesis following conditional VEGF induction in the adult brain and showed that a short episode of VEGF exposure withdrawn shortly after the generation of durable new vessels (but not under conditions where newly made vessels failed to persist) is sufficient for neurogenesis to proceed at a markedly elevated level for many months later. Continual neurogenic increase over several months was not accompanied by accelerated exhaustion of the neuronal stem cell (NSC) reserve, thereby allowing neurogenesis to proceed at a markedly elevated rate also in old mice. Neurogenic enhancement by VEGF preconditioning was, in part, attributed to rescue of age-related NSC quiescence. Remarkably, VEGF caused extensive NSC remodelling manifested in transition of the enigmatic NSC terminal arbor onto long cytoplasmic processes engaging with and spreading over even remote blood vessels, a configuration reminiscent of early postnatal "juvenile" NSCs. Together, these findings suggest that VEGF preconditioning might be harnessed for long-term neurogenic enhancement despite continued exposure to an "aged" systemic milieu.
Collapse
|
14
|
Traumatic Brain Injury Stimulates Neural Stem Cell Proliferation via Mammalian Target of Rapamycin Signaling Pathway Activation. eNeuro 2016; 3:eN-NWR-0162-16. [PMID: 27822507 PMCID: PMC5089538 DOI: 10.1523/eneuro.0162-16.2016] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Revised: 09/07/2016] [Accepted: 09/23/2016] [Indexed: 12/31/2022] Open
Abstract
Neural stem cells in the adult brain possess the ability to remain quiescent until needed in tissue homeostasis or repair. It was previously shown that traumatic brain injury (TBI) stimulated neural stem cell (NSC) proliferation in the adult hippocampus, indicating an innate repair mechanism, but it is unknown how TBI promotes NSC proliferation. In the present study, we observed dramatic activation of mammalian target of rapamycin complex 1 (mTORC1) in the hippocampus of mice with TBI from controlled cortical impact (CCI). The peak of mTORC1 activation in the hippocampal subgranular zone, where NSCs reside, is 24-48 h after trauma, correlating with the peak of TBI-enhanced NSC proliferation. By use of a Nestin-GFP transgenic mouse, in which GFP is ectopically expressed in the NSCs, we found that TBI activated mTORC1 in NSCs. With 5-bromo-2'-deoxyuridine labeling, we observed that TBI increased mTORC1 activation in proliferating NSCs. Furthermore, administration of rapamycin abolished TBI-promoted NSC proliferation. Taken together, these data indicate that mTORC1 activation is required for NSC proliferation postinjury, and thus might serve as a therapeutic target for interventions to augment neurogenesis for brain repair after TBI.
Collapse
|
15
|
Chuang TT. Interplanetary regenerative medicine for mission Mars of SpaceX and NASA. Regen Med 2016; 11:427-9. [PMID: 27344934 DOI: 10.2217/rme-2016-0061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Affiliation(s)
- Tsu Tshen Chuang
- Plasticell Ltd, Stevenage Bioscience Catalyst, Gunnels Wood Road, Stevenage, SG1 2FX, UK
| |
Collapse
|
16
|
The proliferation of amplifying neural progenitor cells is impaired in the aging brain and restored by the mTOR pathway activation. Neurobiol Aging 2015; 36:1716-1726. [PMID: 25655438 DOI: 10.1016/j.neurobiolaging.2015.01.003] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2014] [Revised: 12/10/2014] [Accepted: 01/03/2015] [Indexed: 11/21/2022]
Abstract
A decrease in neurogenesis in the aged brain has been correlated with cognitive decline. The molecular signaling that regulates age-related decline in neurogenesis is still not fully understood. We found that different subtypes of neural stem cells (NSCs) in the hippocampus were differentially impaired by aging. The quiescent NSCs decreased slowly, although the active NSCs exhibited a sharp and dramatic decline from the ages of 6-9 months and became more quiescent at an early stage during the aging process. The activity of the mammalian target of rapamycin (mTOR) signal pathway is compromised in the NSCs of the aged brain. Activating the mTOR signaling pathway increased NSC proliferation and promoted neurogenesis in aged mice. In contrast, inhibiting the mTOR signaling pathway decreased NSCs proliferation. These results indicate that an age-associated decline in neurogenesis is mainly because of the reduction in proliferation of active NSCs, at least partially because of the compromise in the mTOR signaling activity. Stimulating the mTOR signaling revitalizes the NSCs, restores their proliferation, and enhances neurogenesis in the hippocampus of the aged brain.
Collapse
|
17
|
Chen J, Shi R. Current advances in neurotrauma research: diagnosis, neuroprotection, and neurorepair. Neural Regen Res 2014; 9:1093-5. [PMID: 25206764 PMCID: PMC4146094 DOI: 10.4103/1673-5374.135306] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/05/2014] [Indexed: 01/20/2023] Open
Affiliation(s)
- Jinhui Chen
- Department of Neurological Surgery, Stark Neuroscience Research Institute, Department of Anatomy, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Riyi Shi
- Department of Basic Medical Sciences, College of Veterinary Medicine, Purdue University, West Lafayette, IN, USA ; Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, USA
| |
Collapse
|
18
|
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.
Collapse
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.
| |
Collapse
|
19
|
Park JH, Lee H, Makaryus R, Yu M, Smith SD, Sayed K, Feng T, Holland E, Van der Linden A, Bolwig TG, Enikolopov G, Benveniste H. Metabolic profiling of dividing cells in live rodent brain by proton magnetic resonance spectroscopy (1HMRS) and LCModel analysis. PLoS One 2014; 9:e94755. [PMID: 24819091 PMCID: PMC4018321 DOI: 10.1371/journal.pone.0094755] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2013] [Accepted: 03/19/2014] [Indexed: 02/04/2023] Open
Abstract
Rationale Dividing cells can be detected in the live brain by positron emission tomography or optical imaging. Here we apply proton magnetic resonance spectroscopy (1HMRS) and a widely used spectral fitting algorithm to characterize the effect of increased neurogenesis after electroconvulsive shock in the live rodent brain via spectral signatures representing mobile lipids resonating at ∼1.30 ppm. In addition, we also apply the same 1HMRS methodology to metabolically profile glioblastomas with actively dividing cells growing in RCAS-PDGF mice. Methods 1HMRS metabolic profiles were acquired on a 9.4T MRI instrument in combination with LCModel spectral analysis of: 1) rat brains before and after ECS or sham treatments and 2) RCAS-PDGF mice with glioblastomas and wild-type controls. Quantified 1HMRS data were compared to post-mortem histology. Results Dividing cells in the rat hippocampus increased ∼3-fold after ECS compared to sham treatment. Quantification of hippocampal metabolites revealed significant decreases in N-acetyl-aspartate but no evidence of an elevated signal at ∼1.3 ppm (Lip13a+Lip13b) in the ECS compared to the sham group. In RCAS-PDGF mice a high density (22%) of dividing cells characterized glioblastomas. Nile Red staining revealed a small fraction (3%) of dying cells with intracellular lipid droplets in the tumors of RCAS-PDGF mice. Concentrations of NAA were lower, whereas lactate and Lip13a+Lip13b were found to be significantly higher in glioblastomas of RCAS-PDGF mice, when compared to normal brain tissue in the control mice. Conclusions Metabolic profiling using 1HMRS in combination with LCModel analysis did not reveal correlation between Lip13a+Lip13b spectral signatures and an increase in neurogenesis in adult rat hippocampus after ECS. However, increases in Lip13a+Lip13b were evident in glioblastomas suggesting that a higher density of actively dividing cells and/or the presence of lipid droplets is necessary for LCModel to reveal mobile lipids.
Collapse
Affiliation(s)
- June-Hee Park
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, United States of America
| | - Hedok Lee
- Department of Anesthesiology, Stony Brook Medicine, Stony Brook, New York, United States of America
| | - Rany Makaryus
- Department of Anesthesiology, Stony Brook Medicine, Stony Brook, New York, United States of America
| | - Mei Yu
- Department of Anesthesiology, Stony Brook Medicine, Stony Brook, New York, United States of America
| | - S. David Smith
- Department of Anesthesiology, Stony Brook Medicine, Stony Brook, New York, United States of America
| | - Kasim Sayed
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, United States of America
| | - Tian Feng
- Department of Applied Mathematics and Statistics, Stony Brook University, New York, United States of America
| | - Eric Holland
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
| | - Annemie Van der Linden
- Department of Biomedical Sciences, Bio-Imaging Laboratory, University of Antwerp, Belgium
| | - Tom G. Bolwig
- Neuropsychiatry Laboratory, Copenhagen University Hospital, Copenhagen, Denmark
| | - Grigori Enikolopov
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, United States of America
| | - Helene Benveniste
- Department of Anesthesiology, Stony Brook Medicine, Stony Brook, New York, United States of America
- Department of Radiology, Stony Brook Medicine, Stony Brook, New York, United States of America
- * E-mail:
| |
Collapse
|
20
|
Tseng BP, Giedzinski E, Izadi A, Suarez T, Lan ML, Tran KK, Acharya MM, Nelson GA, Raber J, Parihar VK, Limoli CL. Functional consequences of radiation-induced oxidative stress in cultured neural stem cells and the brain exposed to charged particle irradiation. Antioxid Redox Signal 2014; 20:1410-22. [PMID: 23802883 PMCID: PMC3936501 DOI: 10.1089/ars.2012.5134] [Citation(s) in RCA: 100] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
AIMS Redox homeostasis is critical in regulating the fate and function of multipotent cells in the central nervous system (CNS). Here, we investigated whether low dose charged particle irradiation could elicit oxidative stress in neural stem and precursor cells and whether radiation-induced changes in redox metabolism would coincide with cognitive impairment. RESULTS Low doses (<1 Gy) of charged particles caused an acute and persistent oxidative stress. Early after (<1 week) irradiation, increased levels of reactive oxygen and nitrogen species were generally dose responsive, but were less dependent on dose weeks to months thereafter. Exposure to ion fluences resulting in less than one ion traversal per cell was sufficient to elicit radiation-induced oxidative stress. Whole body irradiation triggered a compensatory response in the rodent brain that led to a significant increase in antioxidant capacity 2 weeks following exposure, before returning to background levels at week 4. Low dose irradiation was also found to significantly impair novel object recognition in mice 2 and 12 weeks following irradiation. INNOVATION Data provide evidence that acute exposure of neural stem cells and the CNS to very low doses and fluences of charged particles can elicit a persisting oxidative stress lasting weeks to months that is associated with impaired cognition. CONCLUSIONS Exposure to low doses of charged particles causes a persistent oxidative stress and cognitive impairment over protracted times. Data suggest that astronauts subjected to space radiation may develop a heightened risk for mission critical performance decrements in space, along with a risk of developing long-term neurocognitive sequelae.
Collapse
Affiliation(s)
- Bertrand P Tseng
- 1 Department of Internal Medicine, Duke University Medical Center , Durham, North Carolina
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
21
|
Rivera PD, Shih HY, Leblanc JA, Cole MG, Amaral WZ, Mukherjee S, Zhang S, Lucero MJ, Decarolis NA, Chen BPC, Eisch AJ. Acute and fractionated exposure to high-LET (56)Fe HZE-particle radiation both result in similar long-term deficits in adult hippocampal neurogenesis. Radiat Res 2013; 180:658-67. [PMID: 24320054 DOI: 10.1667/rr13480.1] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Astronauts on multi-year interplanetary missions will be exposed to a low, chronic dose of high-energy, high-charge particles. Studies in rodents show acute, nonfractionated exposure to these particles causes brain changes such as fewer adult-generated hippocampal neurons and stem cells that may be detrimental to cognition and mood regulation and thus compromise mission success. However, the influence of a low, chronic dose of these particles on neurogenesis and stem cells is unknown. To examine the influence of galactic cosmic radiation on neurogenesis, adult-generated stem and progenitor cells in Nestin-CreER(T2)/R26R-YFP transgenic mice were inducibly labeled to allow fate tracking. Mice were then sham exposed or given one acute 100 cGy (56)Fe-particle exposure or five fractionated 20 cGy (56)Fe-particle exposures. Adult-generated hippocampal neurons and stem cells were quantified 24 h or 3 months later. Both acute and fractionated exposure decreased the amount of proliferating cells and immature neurons relative to sham exposure. Unexpectedly, neither acute nor fractionated exposure decreased the number of adult neural stem cells relative to sham expsoure. Our findings show that single and fractionated exposures of (56)Fe-particle irradiation are similarly detrimental to adult-generated neurons. Implications for future missions and ground-based studies in space radiation are discussed.
Collapse
Affiliation(s)
- Phillip D Rivera
- a Department of Psychiatry, UT Southwestern Medical Center, Dallas, Texas 75390-9070; and
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
22
|
Abstract
It is increasingly apparent that treatment with a variety of anticancer agents often is associated with adverse neurological consequences. Clinical studies indicate that exposure even to tamoxifen (TMX), a putatively benign antihormonal agent widely used in breast cancer treatment, causes cognitive dysfunction and changes in CNS metabolism, hippocampal volume, and brain structure. We found that TMX is toxic for a variety of CNS cell populations in vitro and also increased cell death in the corpus callosum and reduced cell division in the mouse subventricular zone, the hippocampal dentate gyrus, and the corpus callosum. We further discovered that MEK1/2 inhibition selectively rescued primary glial progenitors from TMX toxicity in vitro while enhancing TMX effects on MCF7 luminal human breast cancer cells. In vivo, MEK1/2 inhibition prevented TMX-induced cell death in systemically treated mice. Our results demonstrate unexpected cytotoxicity of this putatively benign antihormonal agent and offer a potential strategy for rescuing CNS cells from adverse effects of TMX.
Collapse
|
23
|
Cherry JD, Liu B, Frost JL, Lemere CA, Williams JP, Olschowka JA, O’Banion MK. Galactic cosmic radiation leads to cognitive impairment and increased aβ plaque accumulation in a mouse model of Alzheimer's disease. PLoS One 2012; 7:e53275. [PMID: 23300905 PMCID: PMC3534034 DOI: 10.1371/journal.pone.0053275] [Citation(s) in RCA: 132] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2012] [Accepted: 11/27/2012] [Indexed: 01/11/2023] Open
Abstract
Galactic Cosmic Radiation consisting of high-energy, high-charged (HZE) particles poses a significant threat to future astronauts in deep space. Aside from cancer, concerns have been raised about late degenerative risks, including effects on the brain. In this study we examined the effects of (56)Fe particle irradiation in an APP/PS1 mouse model of Alzheimer's disease (AD). We demonstrated 6 months after exposure to 10 and 100 cGy (56)Fe radiation at 1 GeV/µ, that APP/PS1 mice show decreased cognitive abilities measured by contextual fear conditioning and novel object recognition tests. Furthermore, in male mice we saw acceleration of Aβ plaque pathology using Congo red and 6E10 staining, which was further confirmed by ELISA measures of Aβ isoforms. Increases were not due to higher levels of amyloid precursor protein (APP) or increased cleavage as measured by levels of the β C-terminal fragment of APP. Additionally, we saw no change in microglial activation levels judging by CD68 and Iba-1 immunoreactivities in and around Aβ plaques or insulin degrading enzyme, which has been shown to degrade Aβ. However, immunohistochemical analysis of ICAM-1 showed evidence of endothelial activation after 100 cGy irradiation in male mice, suggesting possible alterations in Aβ trafficking through the blood brain barrier as a possible cause of plaque increase. Overall, our results show for the first time that HZE particle radiation can increase Aβ plaque pathology in an APP/PS1 mouse model of AD.
Collapse
Affiliation(s)
- Jonathan D. Cherry
- Department of Pathology and Laboratory Medicine, University of Rochester School of Medicine and Dentistry, Rochester, New York, United States of America
| | - Bin Liu
- Center for Neurologic Diseases, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Jeffrey L. Frost
- Center for Neurologic Diseases, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Cynthia A. Lemere
- Center for Neurologic Diseases, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Jacqueline P. Williams
- Department of Radiation Oncology, University of Rochester School of Medicine and Dentistry, Rochester, New York, United States of America
| | - John A. Olschowka
- Department of Neurobiology & Anatomy, University of Rochester School of Medicine and Dentistry, Rochester, New York, United States of America
| | - M. Kerry O’Banion
- Department of Neurobiology & Anatomy, University of Rochester School of Medicine and Dentistry, Rochester, New York, United States of America
| |
Collapse
|
24
|
Gao X, Chen J. Moderate traumatic brain injury promotes neural precursor proliferation without increasing neurogenesis in the adult hippocampus. Exp Neurol 2012; 239:38-48. [PMID: 23022454 DOI: 10.1016/j.expneurol.2012.09.012] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2012] [Revised: 09/12/2012] [Accepted: 09/20/2012] [Indexed: 01/22/2023]
Abstract
Traumatic brain injury (TBI) promotes neural stem/progenitor cell (NSC) proliferation in the adult hippocampus; however, it remains inconclusive whether proliferation of these cells results in newly generated mature neurons, leading to increased neurogenesis. When we traced the fates of proliferating cells labeled with bromodeoxyuridine (5-bromo-2-deoxyuridine, BrdU) we found that the number of BrdU-positive cells increased in the hippocampus of TBI mice compared to the sham control. However, double immunostaining to distinguish their cell types showed that most of these cells were glia, and that only a small subpopulation is newborn granular neurons. There was no significant difference with respect to neurogenesis in the adult hippocampus between the injured and the control mice. These results indicate that TBI promotes cell proliferation including astrocyte activation and NSC proliferation. Nevertheless, the majority of the BrdU-positive cells are glia. The neurogenesis is not increased by TBI. These data suggest that TBI activates through promotion of NSC proliferation an innate repair and/or plasticity mechanism in the brain. However, additional intervention is required to increase neurogenesis for successfully repairing the damaged brain following TBI.
Collapse
Affiliation(s)
- Xiang Gao
- Spinal Cord and Brain Injury Research Group, Stark Neuroscience Research Institute, and Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | | |
Collapse
|
25
|
Abstract
Both embryonic and adult neurogenesis involves the self-renewal/proliferation, survival, migration and lineage differentiation of neural stem/progenitor cells. Such dynamic process is tightly regulated by intrinsic and extrinsic factors and complex signaling pathways. Misregulated neurogenesis contributes much to a large range of neurodevelopmental defects and neurodegenerative diseases. The signaling of NFκB regulates many genes important in inflammation, immunity, cell survival and neural plasticity. During neurogenesis, NFκB signaling mediates the effect of numerous niche factors such as cytokines, chemokines, growth factors, extracellular matrix molecules, but also crosstalks with other signaling pathways such as Notch, Shh, Wnt/β-catenin. This review summarizes current progress on the NFκB signaling in all aspects of neurogenesis, focusing on the novel role of NFκB signaling in initiating early neural differentiation of neural stem cells and embryonic stem cells.
Collapse
Affiliation(s)
- Yonggang Zhang
- Department of Neuroscience, Temple University School of Medicine, Philadelphia, PA 19140, USA
| | | |
Collapse
|
26
|
Tan YF, Rosenzweig S, Jaffray D, Wojtowicz JM. Depletion of new neurons by image guided irradiation. Front Neurosci 2011; 5:59. [PMID: 21541259 PMCID: PMC3083759 DOI: 10.3389/fnins.2011.00059] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2011] [Accepted: 04/07/2011] [Indexed: 01/25/2023] Open
Abstract
Ionizing radiation continues to be a relevant tool in both imaging and the treatment of cancer. Experimental uses of focal irradiation have recently been expanded to studies of new neurons in the adult brain. Such studies have shown cognitive deficits following radiation treatment and raised caution as to possible unintentional effects that may occur in humans. Conflicting outcomes of the effects of irradiation on adult neurogenesis suggest that the effects are either transient or permanent. In this study, we used an irradiation apparatus employed in the treatment of human tumors to assess radiation effects on rat neurogenesis. For subjects we used adult male rats (Sprague-Dawley) under anesthesia. The irradiation beam was directed at the hippocampus, a center for learning and memory, and the site of neurogenic activity in adult brain. The irradiation was applied at a dose-rate 0.6 Gy/min for total single-fraction, doses ranging from 0.5 to 10.0 Gy. The animals were returned to home cages and recovered with no sign of any side effects. The neurogenesis was measured either 1 week or 6 weeks after the irradiation. At 1 week, the number of neuronal progenitors was reduced in a dose-dependent manner with the 50% reduction at 0.78 Gy. The dose–response curve was well fitted by a double exponential suggesting two processes. Examination of the tissue with quantitative immunohistochemistry revealed a dominant low-dose effect on neuronal progenitors resulting in 80% suppression of neurogenesis. This effect was partially reversible, possibly due to compensatory proliferation of the remaining precursors. At higher doses (>5 Gy) there was additional, nearly complete block of neurogenesis without compensatory proliferation. We conclude that notwithstanding the usefulness of irradiation for experimental purposes, the exposure of human subjects to doses often used in radiotherapy treatment could be damaging and cause cognitive impairments.
Collapse
Affiliation(s)
- Y-F Tan
- Department of Physiology, Faculty of Medicine, University of Toronto Toronto, ON, Canada
| | | | | | | |
Collapse
|
27
|
Risks and Mechanisms of Oncological Disease Following Stem Cell Transplantation. Stem Cell Rev Rep 2010; 6:411-24. [DOI: 10.1007/s12015-010-9134-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
|
28
|
Gao X, Enikolopov G, Chen J. Moderate traumatic brain injury promotes proliferation of quiescent neural progenitors in the adult hippocampus. Exp Neurol 2009; 219:516-23. [PMID: 19615997 DOI: 10.1016/j.expneurol.2009.07.007] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2009] [Revised: 06/16/2009] [Accepted: 07/06/2009] [Indexed: 12/13/2022]
Abstract
Recent evidence shows that traumatic brain injury (TBI) regulates proliferation of neural stem/progenitor cells in the dentate gyrus (DG) of adult hippocampus. There are distinct classes of neural stem/progenitor cells in the adult DG, including quiescent neural progenitors (QNPs), which carry stem cell properties, and their progeny, amplifying neural progenitors (ANPs). The response of each class of progenitors to TBI is not clear. We here used a transgenic reporter Nestin-GFP mouse line, in which QNP and ANP cells are easily visualized and quantified, to determine the targets of the TBI in the DG. We examined changes in proliferation of QNPs and ANPs in the acute phase following TBI and found that QNPs were induced by TBI insult to enter the cell cycle whereas proliferation of ANPs was not significantly affected. These results indicate that different subtypes of neural stem/progenitor cells respond differently to TBI insult. Stem cell activation by the TBI may reflect the induction of innate repair and plasticity mechanisms by the injured brain.
Collapse
Affiliation(s)
- Xiang Gao
- Spinal Cord and Brain Injury Research Group, Stark Neuroscience Research Institute, and Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | | | | |
Collapse
|
29
|
Abstract
Psychiatric and neurologic disorders take an enormous toll on society. Alleviating the devastating symptoms and consequences of neuropsychiatric disorders such as addiction, depression, epilepsy, and schizophrenia is a main force driving clinical and basic researchers alike. By elucidating these disease neuromechanisms, researchers hope to better define treatments and preventive therapies. Research suggests that regulation of adult hippocampal neurogenesis represents a promising approach to treating and perhaps preventing mental illness. Here we appraise the role of adult hippocampal neurogenesis in major psychiatric and neurologic disorders within the essential framework of recent progress made in understanding "normal" adult neurogenesis. Topics addressed include the following: the life cycle of an adult hippocampal stem cell and the implications for aging; links between learning and hippocampal neurogenesis; the reciprocal relationship between cocaine self-administration and adult hippocampal neurogenesis; the role of adult neurogenesis in an animal model of depression and response to antidepressant exposure; the impact of neonatal seizures on dentate gyrus neurogenesis; and the contribution of a schizophrenia-susceptibility gene to adult hippocampal neurogenesis. These topics are discussed in light of the regulation of adult neurogenesis, the relationship to normal neurogenesis in adulthood and aging, and, importantly, the manipulation of neurogenesis to promote mental health and treat mental illness.
Collapse
|
30
|
Dimitrov BD, Rachkova MI, Atanassova PA. Cyclic patterns of incidence rate for skin malignant melanoma: association with heliogeophysical activity. J Zhejiang Univ Sci B 2008; 9:489-95. [PMID: 18543403 DOI: 10.1631/jzus.b0820076] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
BACKGROUND Our previous studies revealed cyclicity in the incidence rate of skin malignant melanoma (SMM; ICD9, Dx:172) in the Czech Republic (period T=7.50-7.63 years), UK (T=11.00 years) and Bulgaria (T=12.20 years). Incidences compared with the sunspot index Rz (lag-period dT=+2, +4, +6, +10 or +12 years) have indicated that maximal rates are most likely to appear on descending slopes of the 11-year solar cycle, i.e., out of phase. We summarized and explored more deeply these cyclic variations and discussed their possible associations with heliogeophysical activity (HGA) components exhibiting similar cyclicity. METHODS Annual incidences of SMM from 5 countries (Czech Republic, UK, Bulgaria, USA and Canada) over various time spans during the years 1964-1992 were analyzed and their correlations with cyclic Rz (sunspot number) and aa (planetary geomagnetic activity) indices were summarized. Periodogram regression analysis with trigonometric approximation and phase-correlation analysis were applied. RESULTS Previous findings on SMM for the Czech Republic, UK and Bulgaria have been validated, and cyclic patterns have been revealed for USA (T=8.63 years, P<0.05) and Canada (Ontario, T=9.91 years, P<0.10). Also, various 'hypercycles' were established (T=45.5, 42.0, 48.25, 34.5 and 26.5 years, respectively) describing long-term cyclic incidence patterns. The association of SMM for USA and Canada with Rz (dT=+6 and +7 years, respectively) and aa (dT=-10 and +9 years, respectively) was described. Possible interactions of cyclic non-photic influences (UV irradiation, Schumann resonance signal, low-frequency geomagnetic fluctuations) with brain waves absorbance, neuronal calcium dynamics, neuro-endocrine axis modulation, melatonin/serotonin disbalance and skin neuro-immunity impairment as likely causal pathways in melanoma appearance, were also discussed. CONCLUSION The above findings on cyclicity and temporal association of SMM with cyclic environmental factors could not only allow for better forecasting models but also lead to a better understanding of melanoma aetiology.
Collapse
|