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Raber J, Holden S, Kessler K, Glaeser B, McQuesten C, Chaudhari M, Stenzel F, Lenarczyk M, Leonard SW, Morré J, Choi J, Kronenberg A, Borg A, Kwok A, Stevens JF, Olsen C, Willey JS, Bobe G, Minnier J, Baker JE. Effects of photon irradiation in the presence and absence of hindlimb unloading on the behavioral performance and metabolic pathways in the plasma of Fischer rats. Front Physiol 2024; 14:1316186. [PMID: 38260101 PMCID: PMC10800373 DOI: 10.3389/fphys.2023.1316186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Accepted: 12/11/2023] [Indexed: 01/24/2024] Open
Abstract
Introduction: The space environment astronauts experience during space missions consists of multiple environmental challenges, including microgravity. In this study, we assessed the behavioral and cognitive performances of male Fisher rats 2 months after sham irradiation or total body irradiation with photons in the absence or presence of simulated microgravity. We analyzed the plasma collected 9 months after sham irradiation or total body irradiation for distinct alterations in metabolic pathways and to determine whether changes to metabolic measures were associated with specific behavioral and cognitive measures. Methods: A total of 344 male Fischer rats were irradiated with photons (6 MeV; 3, 8, or 10 Gy) in the absence or presence of simulated weightlessness achieved using hindlimb unloading (HU). To identify potential plasma biomarkers of photon radiation exposure or the HU condition for behavioral or cognitive performance, we performed regression analyses. Results: The behavioral effects of HU on activity levels in an open field, measures of anxiety in an elevated plus maze, and anhedonia in the M&M consumption test were more pronounced than those of photon irradiation. Phenylalanine, tyrosine, and tryptophan metabolism, and phenylalanine metabolism and biosynthesis showed very strong pathway changes, following photon irradiation and HU in animals irradiated with 3 Gy. Here, 29 out of 101 plasma metabolites were associated with 1 out of 13 behavioral measures. In the absence of HU, 22 metabolites were related to behavioral and cognitive measures. In HU animals that were sham-irradiated or irradiated with 8 Gy, one metabolite was related to behavioral and cognitive measures. In HU animals irradiated with 3 Gy, six metabolites were related to behavioral and cognitive measures. Discussion: These data suggest that it will be possible to develop stable plasma biomarkers of behavioral and cognitive performance, following environmental challenges like HU and radiation exposure.
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Affiliation(s)
- Jacob Raber
- Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, OR, United States
- Departments of Neurology, and Radiation Medicine, Division of Neuroscience ONPRC, Oregon Health & Science University, Portland, OR, United States
- College of Pharmacy, Oregon State University, Corvallis, OR, United States
| | - Sarah Holden
- Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, OR, United States
| | - Kat Kessler
- Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, OR, United States
| | - Breanna Glaeser
- Neuroscience Center and Department of Pharmacology and Toxicology, Medical College of Wisconsin, Milwaukee, WI, United States
| | - Chloe McQuesten
- Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, OR, United States
| | - Mitali Chaudhari
- Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, OR, United States
| | - Fiona Stenzel
- Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, OR, United States
| | - Marek Lenarczyk
- Radiation Biosciences Laboratory, Medical College of Wisconsin, Milwaukee, WI, United States
| | - Scott Willem Leonard
- Department of Radiation Oncology, Wake Forest School of Medicine, Winston-Salem, NC, United States
| | - Jeffrey Morré
- Mass Spectrometry Core, Oregon State University, Corvallis, OR, United States
| | - Jaewoo Choi
- Linus Pauling Institute, Oregon State University, Corvallis, OR, United States
| | - Amy Kronenberg
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA, United States
| | - Alexander Borg
- Department of Radiation Oncology, Wake Forest School of Medicine, Winston-Salem, NC, United States
| | - Andy Kwok
- Department of Radiation Oncology, Wake Forest School of Medicine, Winston-Salem, NC, United States
| | - Jan Frederik Stevens
- College of Pharmacy, Oregon State University, Corvallis, OR, United States
- Linus Pauling Institute, Oregon State University, Corvallis, OR, United States
| | - Christopher Olsen
- Neuroscience Center and Department of Pharmacology and Toxicology, Medical College of Wisconsin, Milwaukee, WI, United States
| | - Jeffrey S. Willey
- Department of Radiation Oncology, Wake Forest School of Medicine, Winston-Salem, NC, United States
| | - Gerd Bobe
- Linus Pauling Institute, Oregon State University, Corvallis, OR, United States
- Department of Animal Sciences, Oregon State University, Corvallis, OR, United States
| | - Jessica Minnier
- Oregon Health & Science University-Portland State University School of Public Health, Knight Cancer Institute Biostatistics Shared Resource, The Knight Cardiovascular Institute, OR Health & Science University, Portland, OR, United States
| | - John E. Baker
- Neuroscience Center and Department of Pharmacology and Toxicology, Medical College of Wisconsin, Milwaukee, WI, United States
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Cahill T, Chan S, Overton IM, Hardiman G. Transcriptome Profiling Reveals Enhanced Mitochondrial Activity as a Cold Adaptive Strategy to Hypothermia in Zebrafish Muscle. Cells 2023; 12:1366. [PMID: 37408201 PMCID: PMC10216211 DOI: 10.3390/cells12101366] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Revised: 05/01/2023] [Accepted: 05/07/2023] [Indexed: 07/07/2023] Open
Abstract
The utilisation of synthetic torpor for interplanetary travel once seemed farfetched. However, mounting evidence points to torpor-induced protective benefits from the main hazards of space travel, namely, exposure to radiation and microgravity. To determine the radio-protective effects of an induced torpor-like state we exploited the ectothermic nature of the Danio rerio (zebrafish) in reducing their body temperatures to replicate the hypothermic states seen during natural torpor. We also administered melatonin as a sedative to reduce physical activity. Zebrafish were then exposed to low-dose radiation (0.3 Gy) to simulate radiation exposure on long-term space missions. Transcriptomic analysis found that radiation exposure led to an upregulation of inflammatory and immune signatures and a differentiation and regeneration phenotype driven by STAT3 and MYOD1 transcription factors. In addition, DNA repair processes were downregulated in the muscle two days' post-irradiation. The effects of hypothermia led to an increase in mitochondrial translation including genes involved in oxidative phosphorylation and a downregulation of extracellular matrix and developmental genes. Upon radiation exposure, increases in endoplasmic reticulum stress genes were observed in a torpor+radiation group with downregulation of immune-related and ECM genes. Exposing hypothermic zebrafish to radiation also resulted in a downregulation of ECM and developmental genes however, immune/inflammatory related pathways were downregulated in contrast to that observed in the radiation only group. A cross-species comparison was performed with the muscle of hibernating Ursus arctos horribilis (brown bear) to define shared mechanisms of cold tolerance. Shared responses show an upregulation of protein translation and metabolism of amino acids, as well as a hypoxia response with the shared downregulation of glycolysis, ECM, and developmental genes.
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Affiliation(s)
- Thomas Cahill
- School of Biological Sciences, Institute for Global Food Security, Queen’s University Belfast, Belfast BT9 5DL, UK;
| | - Sherine Chan
- Department of Drug Discovery and Biomedical Sciences, Medical University of South Carolina, Charleston, SC 29425, USA;
- JLABS at the Children’s National Research and Innovation Campus, Washington, DC 20012, USA
| | - Ian M. Overton
- Patrick G Johnston Centre for Cancer Research, Queen’s University Belfast, Belfast BT9 7AE, UK;
| | - Gary Hardiman
- School of Biological Sciences, Institute for Global Food Security, Queen’s University Belfast, Belfast BT9 5DL, UK;
- Department of Drug Discovery and Biomedical Sciences, Medical University of South Carolina, Charleston, SC 29425, USA;
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3
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Wiggs MP, Lee Y, Shimkus KL, O'Reilly CI, Lima F, Macias BR, Shirazi-Fard Y, Greene ES, Hord JM, Braby LA, Carroll CC, Lawler JM, Bloomfield SA, Fluckey JD. Combined effects of heavy ion exposure and simulated Lunar gravity on skeletal muscle. LIFE SCIENCES IN SPACE RESEARCH 2023; 37:39-49. [PMID: 37087178 DOI: 10.1016/j.lssr.2023.02.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Revised: 01/04/2023] [Accepted: 02/19/2023] [Indexed: 05/03/2023]
Abstract
BACKGROUND The limitations to prolonged spaceflight include unloading-induced atrophy of the musculoskeletal system which may be enhanced by exposure to the space radiation environment. Previous results have concluded that partial gravity, comparable to the Lunar surface, may have detrimental effects on skeletal muscle. However, little is known if these outcomes are exacerbated by exposure to low-dose rate, high-energy radiation common to the space environment. Therefore, the present study sought to determine the impact of highly charge, high-energy (HZE) radiation on skeletal muscle when combined with partial weightbearing to simulate Lunar gravity. We hypothesized that partial unloading would compromise skeletal muscle and these effects would be exacerbated by radiation exposure. METHODS For month old female BALB/cByJ mice were -assigned to one of 2 groups; either full weight bearing (Cage Controls, CC) or partial weight bearing equal to 1/6th bodyweight (G/6). Both groups were then divided to receive either a single whole body absorbed dose of 0.5 Gy of 300 MeV 28Si ions (RAD) or a sham treatment (SHAM). Radiation exposure experiments were performed at the NASA Space Radiation Laboratory (NSRL) located at Brookhaven National Laboratory on Day 0, followed by 21 d of CC or G/6 loading. Muscles of the hind limb were used to measure protein synthesis and other histological measures. RESULTS Twenty-one days of Lunar gravity (G/6) resulted in lower soleus, plantaris, and gastrocnemius muscle mass. Radiation exposure did not further impact muscle mass. 28Si exposure in normal ambulatory animals (RAD+CC) did not impact gastrocnemius muscle mass when compared to SHAM+CC (p>0.05), but did affect the soleus, where mass was higher following radiation compared to SHAM (p<0.05). Mixed gastrocnemius muscle protein synthesis was lower in both unloading groups. Fiber type composition transitioned towards a faster isoform with partial unloading and was not further impacted by radiation. The combined effects of partial loading and radiation partially mitigated fiber cross-sectional area when compared to partial loading alone. Radiation and G/6 reduced the total number of myonuclei per fiber while leading to elevated BrdU content of skeletal muscle. Similarly, unloading and radiation resulted in higher collagen content of muscle when compared to controls, but the effects of combined exposure were not additive. CONCLUSIONS The results of this study confirm that partial weightbearing causes muscle atrophy, in part due to reductions of muscle protein synthesis in the soleus and gastrocnemius as well as reduced peripheral nuclei per fiber. Additionally, we present novel data illustrating 28Si exposure reduced nuclei in muscle fibers despite higher satellite cell fusion, but did not exacerbate muscle atrophy, CSA changes, or collagen content. In conclusion, both partial loading and HZE radiation can negatively impact muscle morphology.
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Affiliation(s)
- Michael P Wiggs
- Department of Health & Kinesiology, Texas A&M University, College Station, TX, United States; Department of Health, Human Performance and Recreation, Baylor University, Waco, TX, United States.
| | - Yang Lee
- Department of Health & Kinesiology, Texas A&M University, College Station, TX, United States
| | - Kevin L Shimkus
- Department of Health & Kinesiology, Texas A&M University, College Station, TX, United States
| | - Colleen I O'Reilly
- Department of Health & Kinesiology, Texas A&M University, College Station, TX, United States
| | - Florence Lima
- Department of Health & Kinesiology, Texas A&M University, College Station, TX, United States
| | - Brandon R Macias
- Department of Health & Kinesiology, Texas A&M University, College Station, TX, United States; NASA Johnson Space Center, Houston, Texas, United States
| | - Yasaman Shirazi-Fard
- Department of Health & Kinesiology, Texas A&M University, College Station, TX, United States; NASA Ames Research Center, Moffett Field, CA, United States
| | - Elizabeth S Greene
- Department of Health & Kinesiology, Texas A&M University, College Station, TX, United States
| | - Jeffrey M Hord
- Department of Health & Kinesiology, Texas A&M University, College Station, TX, United States
| | - Leslie A Braby
- Department of Nuclear Engineering, Texas A&M University, College Station, TX, United States
| | - Chad C Carroll
- Department of Physiology, Purdue University, West Lafayette, IN, United States
| | - John M Lawler
- Department of Health & Kinesiology, Texas A&M University, College Station, TX, United States
| | - Susan A Bloomfield
- Department of Health & Kinesiology, Texas A&M University, College Station, TX, United States
| | - James D Fluckey
- Department of Health & Kinesiology, Texas A&M University, College Station, TX, United States
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4
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Wong CP, Branscum AJ, Fichter AR, Sargent J, Iwaniec UT, Turner RT. Cold stress during room temperature housing alters skeletal response to simulated microgravity (hindlimb unloading) in growing female C57BL6 mice. Biochimie 2022:S0300-9084(22)00333-9. [PMID: 36584865 DOI: 10.1016/j.biochi.2022.12.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Revised: 11/29/2022] [Accepted: 12/14/2022] [Indexed: 12/29/2022]
Abstract
Laboratory mice are typically housed at temperatures below the thermoneutral zone for the species, resulting in cold stress and premature cancellous bone loss. Furthermore, mice are more dependent upon non-shivering thermogenesis to maintain body temperature during spaceflight, suggesting that microgravity-induced bone loss may be due, in part, to altered thermogenesis. Consequently, we assessed whether housing mice at room temperature modifies the skeletal response to simulated microgravity. This possibility was tested using the hindlimb unloading (HLU) model to mechanically unload femora. Humeri were also assessed as they remain weight bearing during HLU. Six-week-old female C57BL6 (B6) mice were housed at room temperature (22 °C) or near thermoneutral (32 °C) and HLU for 2 weeks. Compared to baseline, HLU resulted in cortical bone loss in femur, but the magnitude of reduction was greater in mice housed at 22 °C. Cancellous osteopenia in distal femur (metaphysis and epiphysis) was noted in HLU mice housed at both temperatures. However, bone loss occurred at 22 °C, whereas the bone deficit at 32 °C was due to failure to accrue bone. HLU resulted in cortical and cancellous bone deficits (compared to baseline) in humeri of mice housed at 22 °C. In contrast, fewer osteopenic changes were detected in mice housed at 32 °C. These findings support the hypothesis that environmental temperature alters the skeletal response to HLU in growing female mice in a bone compartment-specific manner. Taken together, species differences in thermoregulation should be taken into consideration when interpreting the skeletal response to simulated microgravity.
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Affiliation(s)
- Carmen P Wong
- Skeletal Biology Laboratory, School of Biological and Population Health Sciences, Oregon State University, Corvallis, OR, 97331, USA
| | - Adam J Branscum
- Biostatistics Program, School of Biological and Population Health Sciences, Oregon State University, Corvallis, OR, 97331, USA
| | - Aidan R Fichter
- Skeletal Biology Laboratory, School of Biological and Population Health Sciences, Oregon State University, Corvallis, OR, 97331, USA
| | - Jennifer Sargent
- Carlson College of Veterinary Medicine, Oregon State University, Corvallis, OR, 97331 USA
| | - Urszula T Iwaniec
- Skeletal Biology Laboratory, School of Biological and Population Health Sciences, Oregon State University, Corvallis, OR, 97331, USA; Center for Healthy Aging Research, Oregon State University, Corvallis, OR, 97331, USA
| | - Russell T Turner
- Skeletal Biology Laboratory, School of Biological and Population Health Sciences, Oregon State University, Corvallis, OR, 97331, USA; Center for Healthy Aging Research, Oregon State University, Corvallis, OR, 97331, USA.
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5
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Changes in interstitial fluid flow, mass transport and the bone cell response in microgravity and normogravity. Bone Res 2022; 10:65. [PMID: 36411278 PMCID: PMC9678891 DOI: 10.1038/s41413-022-00234-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Revised: 08/17/2022] [Accepted: 08/29/2022] [Indexed: 11/22/2022] Open
Abstract
In recent years, our scientific interest in spaceflight has grown exponentially and resulted in a thriving area of research, with hundreds of astronauts spending months of their time in space. A recent shift toward pursuing territories farther afield, aiming at near-Earth asteroids, the Moon, and Mars combined with the anticipated availability of commercial flights to space in the near future, warrants continued understanding of the human physiological processes and response mechanisms when in this extreme environment. Acute skeletal loss, more severe than any bone loss seen on Earth, has significant implications for deep space exploration, and it remains elusive as to why there is such a magnitude of difference between bone loss on Earth and loss in microgravity. The removal of gravity eliminates a critical primary mechano-stimulus, and when combined with exposure to both galactic and solar cosmic radiation, healthy human tissue function can be negatively affected. An additional effect found in microgravity, and one with limited insight, involves changes in dynamic fluid flow. Fluids provide the most fundamental way to transport chemical and biochemical elements within our bodies and apply an essential mechano-stimulus to cells. Furthermore, the cell cytoplasm is not a simple liquid, and fluid transport phenomena together with viscoelastic deformation of the cytoskeleton play key roles in cell function. In microgravity, flow behavior changes drastically, and the impact on cells within the porous system of bone and the influence of an expanding level of adiposity are not well understood. This review explores the role of interstitial fluid motion and solute transport in porous bone under two different conditions: normogravity and microgravity.
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6
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Millar-Wilson A, Ward Ó, Duffy E, Hardiman G. Multiscale modeling in the framework of biological systems and its potential for spaceflight biology studies. iScience 2022; 25:105421. [DOI: 10.1016/j.isci.2022.105421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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7
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Lee PHU, Chung M, Ren Z, Mair DB, Kim DH. Factors mediating spaceflight-induced skeletal muscle atrophy. Am J Physiol Cell Physiol 2022; 322:C567-C580. [PMID: 35171699 DOI: 10.1152/ajpcell.00203.2021] [Citation(s) in RCA: 34] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Skeletal muscle atrophy is a well-known consequence of spaceflight. Because of the potential significant impact of muscle atrophy and muscle dysfunction on astronauts and to their mission, a thorough understanding of the mechanisms of this atrophy and the development of effective countermeasures is critical. Spaceflight-induced muscle atrophy is similar to atrophy seen in many terrestrial conditions, and therefore our understanding of this form of atrophy may also contribute to the treatment of atrophy in humans on Earth. The unique environmental features humans encounter in space include the weightlessness of microgravity, space radiation, and the distinctive aspects of living in a spacecraft. The disuse and unloading of muscles in microgravity are likely the most significant factors that mediate spaceflight-induced muscle atrophy, and have been extensively studied and reviewed. However, there are numerous other direct and indirect effects on skeletal muscle that may be contributing factors to the muscle atrophy and dysfunction seen as a result of spaceflight. This review offers a novel perspective on the issue of muscle atrophy in space by providing a comprehensive overview of the unique aspects of the spaceflight environment and the various ways in which they can lead to muscle atrophy. We systematically review the potential contributions of these different mechanisms of spaceflight-induced atrophy and include findings from both actual spaceflight and ground-based models of spaceflight in humans, animals, and in vitro studies.
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Affiliation(s)
- Peter H U Lee
- Department of Cardiothoracic Surgery, Southcoast Health, Fall River, MA, United States.,Department of Pathology and Laboratory Medicine, Brown University, Providence, RI, United States
| | | | - Zhanping Ren
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, United States
| | - Devin B Mair
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, United States
| | - Deok-Ho Kim
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, United States
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8
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Tran KN, Choi JI. Mimic microgravity effect on muscle transcriptome under ionizing radiation. LIFE SCIENCES IN SPACE RESEARCH 2022; 32:96-104. [PMID: 35065767 DOI: 10.1016/j.lssr.2021.12.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Revised: 11/30/2021] [Accepted: 12/08/2021] [Indexed: 06/14/2023]
Abstract
Spaceflight imposes the risk of skeletal muscle atrophy for astronauts. Two main factors of a spaceflight that results in deleterious effects are microgravity and cosmic rays in outer space. To study spaceflight-induced muscle atrophy with ground-based models, we performed two models of microgravity, tail suspension and denervation, in a low dose radiation environment and studied transcriptional changes in rat soleus muscle using microarrays. Soleus muscle from rats in the denervation group had greater expression changes compared to that found in rats from the tail suspension group. However, there was a very similar pattern of expression of differentially expressed genes (DEGs) in both models. In total, we identified 144 differentially expressed genes common in both models. Our study yielded two main findings. First, a large number of genes involved in energy metabolism were transcriptionally suppressed including those involved in fatty acid transport and beta-oxidation, and oxidative phosphorylation. Second, slow-twitch contractile protein encoding genes were down-regulated while there was an up-regulation in the fast-twitch type transcription. These results were consistent with other spaceflight studies on the effects on muscle cells, hence showed the potential of our ground-based models in studying spaceflight effects. The genes that might be involved in spaceflight effects will serve as candidate genes for future studies in understanding the mechanism of spaceflight-induced muscle atrophy and result in the development of effective countermeasures.
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Affiliation(s)
- Kim Ngan Tran
- Department of Biotechnology and Bioengineering, Chonnam National University, Gwangju 61186, Republic of Korea
| | - Jong-Il Choi
- Department of Biotechnology and Bioengineering, Chonnam National University, Gwangju 61186, Republic of Korea.
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9
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Tamaddondoust RN, Wang Y, Jafarnejad SM, Graber TE, Alain T. The highs and lows of ionizing radiation and its effects on protein synthesis. Cell Signal 2021; 89:110169. [PMID: 34662715 DOI: 10.1016/j.cellsig.2021.110169] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 08/19/2021] [Accepted: 10/06/2021] [Indexed: 11/03/2022]
Abstract
Ionizing radiation (IR) is a constant feature of our environment and one that can dramatically affect organismal health and development. Although the impacts of high-doses of IR on mammalian cells and systems have been broadly explored, there are still challenges in accurately quantifying biological responses to IR, especially in the low-dose range to which most individuals are exposed in their lifetime. The resulting uncertainty has led to the entrenchment of conservative radioprotection policies around the world. Thus, uncovering long-sought molecular mechanisms and tissue responses that are targeted by IR could lead to more informed policymaking and propose new therapeutic avenues for a variety of pathologies. One often overlooked target of IR is mRNA translation, a highly regulated cellular process that consumes more than 40% of the cell's energy. In response to environmental stimuli, regulation of mRNA translation allows for precise and rapid changes to the cellular proteome, and unsurprisingly high-dose of IR was shown to trigger a severe reprogramming of global protein synthesis allowing the cell to conserve energy by preventing the synthesis of unneeded proteins. Nonetheless, under these conditions, certain mRNAs encoding specific proteins are translationally favoured to produce the factors essential to repair the cell or send it down the path of no return through programmed cell death. Understanding the mechanisms controlling protein synthesis in response to varying doses of IR could provide novel insights into how this stress-mediated cellular adaptation is regulated and potentially uncover novel targets for radiosensitization or radioprotection. Here, we review the current literature on the effects of IR at both high- and low-dose on the mRNA translation machinery.
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Affiliation(s)
- Rosette Niloufar Tamaddondoust
- Molecular Biomedicine Program, Children's Hospital of Eastern Ontario Research Institute, Ottawa, Ontario, Canada; Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Ontario, Canada; Radiobiology and Health, Canadian Nuclear Laboratories, Chalk River, Ontario, Canada.
| | - Yi Wang
- Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Ontario, Canada; Radiobiology and Health, Canadian Nuclear Laboratories, Chalk River, Ontario, Canada
| | - Seyed Mehdi Jafarnejad
- Patrick G. Johnston Centre for Cancer Research, Queen's University Belfast, Belfast BT9 7AE, UK
| | - Tyson E Graber
- Molecular Biomedicine Program, Children's Hospital of Eastern Ontario Research Institute, Ottawa, Ontario, Canada
| | - Tommy Alain
- Molecular Biomedicine Program, Children's Hospital of Eastern Ontario Research Institute, Ottawa, Ontario, Canada; Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Ontario, Canada.
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10
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Raber J, Holden S, Sudhakar R, Hall R, Glaeser B, Lenarczyk M, Rockwell K, Nawarawong N, Sterrett J, Perez R, Leonard SW, Morré J, Choi J, Kronenberg A, Borg A, Kwok A, Stevens JF, Olsen CM, Willey JS, Bobe G, Baker J. Effects of 5-Ion Beam Irradiation and Hindlimb Unloading on Metabolic Pathways in Plasma and Brain of Behaviorally Tested WAG/Rij Rats. Front Physiol 2021; 12:746509. [PMID: 34646164 PMCID: PMC8503608 DOI: 10.3389/fphys.2021.746509] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Accepted: 08/24/2021] [Indexed: 01/13/2023] Open
Abstract
A limitation of simulated space radiation studies is that radiation exposure is not the only environmental challenge astronauts face during missions. Therefore, we characterized behavioral and cognitive performance of male WAG/Rij rats 3 months after sham-irradiation or total body irradiation with a simplified 5-ion mixed beam exposure in the absence or presence of simulated weightlessness using hindlimb unloading (HU) alone. Six months following behavioral and cognitive testing or 9 months following sham-irradiation or total body irradiation, plasma and brain tissues (hippocampus and cortex) were processed to determine whether the behavioral and cognitive effects were associated with long-term alterations in metabolic pathways in plasma and brain. Sham HU, but not irradiated HU, rats were impaired in spatial habituation learning. Rats irradiated with 1.5 Gy showed increased depressive-like behaviors. This was seen in the absence but not presence of HU. Thus, HU has differential effects in sham-irradiated and irradiated animals and specific behavioral measures are associated with plasma levels of distinct metabolites 6 months later. The combined effects of HU and radiation on metabolic pathways in plasma and brain illustrate the complex interaction of environmental stressors and highlights the importance of assessing these interactions.
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Affiliation(s)
- Jacob Raber
- Department of Behavioral Neuroscience, Oregon Health and Science University, Portland, OR, United States.,Department of Neurology, Psychiatry, and Radiation Medicine, Division of Neuroscience, ONPRC, Oregon Health and Science University, Portland, OR, United States.,College of Pharmacy, Oregon State University, Corvallis, OR, United States
| | - Sarah Holden
- Department of Behavioral Neuroscience, Oregon Health and Science University, Portland, OR, United States
| | - Reetesh Sudhakar
- Department of Behavioral Neuroscience, Oregon Health and Science University, Portland, OR, United States
| | - Reed Hall
- Department of Behavioral Neuroscience, Oregon Health and Science University, Portland, OR, United States
| | - Breanna Glaeser
- Department of Pharmacology and Toxicology, Neuroscience Center, Medical College of Wisconsin, Milwaukee, WI, United States
| | - Marek Lenarczyk
- Radiation Biosciences Laboratory, Medical College of Wisconsin, Milwaukee, WI, United States
| | - Kristen Rockwell
- Department of Pharmacology and Toxicology, Neuroscience Center, Medical College of Wisconsin, Milwaukee, WI, United States
| | - Natalie Nawarawong
- Department of Pharmacology and Toxicology, Neuroscience Center, Medical College of Wisconsin, Milwaukee, WI, United States
| | - Jennifer Sterrett
- Department of Pharmacology and Toxicology, Neuroscience Center, Medical College of Wisconsin, Milwaukee, WI, United States
| | - Ruby Perez
- Department of Behavioral Neuroscience, Oregon Health and Science University, Portland, OR, United States
| | - Scott William Leonard
- Department of Radiation Oncology, Wake Forest School of Medicine, Winston-Salem, NC, United States
| | - Jeffrey Morré
- Mass Spectrometry Core, Oregon State University, Corvallis, OR, United States
| | - Jaewoo Choi
- Linus Pauling Institute, Oregon State University, Corvallis, OR, United States
| | - Amy Kronenberg
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA, United States
| | - Alexander Borg
- Department of Radiation Oncology, Wake Forest School of Medicine, Winston-Salem, NC, United States
| | - Andy Kwok
- Department of Radiation Oncology, Wake Forest School of Medicine, Winston-Salem, NC, United States
| | - Jan Frederik Stevens
- College of Pharmacy, Oregon State University, Corvallis, OR, United States.,Linus Pauling Institute, Oregon State University, Corvallis, OR, United States
| | - Christopher M Olsen
- Department of Pharmacology and Toxicology, Neuroscience Center, Medical College of Wisconsin, Milwaukee, WI, United States
| | - Jeffrey S Willey
- Department of Radiation Oncology, Wake Forest School of Medicine, Winston-Salem, NC, United States
| | - Gerd Bobe
- Linus Pauling Institute, Oregon State University, Corvallis, OR, United States.,Department of Animal Sciences, Oregon State University, Corvallis, OR, United States
| | - John Baker
- Department of Pharmacology and Toxicology, Neuroscience Center, Medical College of Wisconsin, Milwaukee, WI, United States.,Radiation Biosciences Laboratory, Medical College of Wisconsin, Milwaukee, WI, United States
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11
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Genchi GG, Degl’Innocenti A, Martinelli C, Battaglini M, De Pasquale D, Prato M, Marras S, Pugliese G, Drago F, Mariani A, Balsamo M, Zolesi V, Ciofani G. Cerium Oxide Nanoparticle Administration to Skeletal Muscle Cells under Different Gravity and Radiation Conditions. ACS APPLIED MATERIALS & INTERFACES 2021; 13:40200-40213. [PMID: 34410709 PMCID: PMC8414486 DOI: 10.1021/acsami.1c14176] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Accepted: 08/05/2021] [Indexed: 05/28/2023]
Abstract
For their remarkable biomimetic properties implying strong modulation of the intracellular and extracellular redox state, cerium oxide nanoparticles (also termed "nanoceria") were hypothesized to exert a protective role against oxidative stress associated with the harsh environmental conditions of spaceflight, characterized by microgravity and highly energetic radiations. Nanoparticles were supplied to proliferating C2C12 mouse skeletal muscle cells under different gravity and radiation levels. Biological responses were thus investigated at a transcriptional level by RNA next-generation sequencing. Lists of differentially expressed genes (DEGs) were generated and intersected by taking into consideration relevant comparisons, which led to the observation of prevailing effects of the space environment over those induced by nanoceria. In space, upregulation of transcription was slightly preponderant over downregulation, implying involvement of intracellular compartments, with the majority of DEGs consistently over- or under-expressed whenever present. Cosmic radiations regulated a higher number of DEGs than microgravity and seemed to promote increased cellular catabolism. By taking into consideration space physical stressors alone, microgravity and cosmic radiations appeared to have opposite effects at transcriptional levels despite partial sharing of molecular pathways. Interestingly, gene ontology denoted some enrichment in terms related to vision, when only effects of radiations were assessed. The transcriptional regulation of mitochondrial uncoupling protein 2 in space-relevant samples suggests perturbation of the intracellular redox homeostasis, and leaves open opportunities for antioxidant treatment for oxidative stress reduction in harsh environments.
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Affiliation(s)
- Giada Graziana Genchi
- Istituto
Italiano di Tecnologia, Smart Bio-Interfaces, Viale Rinaldo Piaggio 34, 56025 Pontedera (Pisa), Italy
| | - Andrea Degl’Innocenti
- Istituto
Italiano di Tecnologia, Smart Bio-Interfaces, Viale Rinaldo Piaggio 34, 56025 Pontedera (Pisa), Italy
| | - Chiara Martinelli
- Istituto
Italiano di Tecnologia, Smart Bio-Interfaces, Viale Rinaldo Piaggio 34, 56025 Pontedera (Pisa), Italy
| | - Matteo Battaglini
- Istituto
Italiano di Tecnologia, Smart Bio-Interfaces, Viale Rinaldo Piaggio 34, 56025 Pontedera (Pisa), Italy
| | - Daniele De Pasquale
- Istituto
Italiano di Tecnologia, Smart Bio-Interfaces, Viale Rinaldo Piaggio 34, 56025 Pontedera (Pisa), Italy
- Scuola
Superiore Sant’Anna, The BioRobotics
Institute, Viale Rinaldo
Piaggio 34, 56025 Pontedera (Pisa), Italy
| | - Mirko Prato
- Istituto
Italiano di Tecnologia, Materials Characterization, Via Morego 30, 16163 Genova, Italy
| | - Sergio Marras
- Istituto
Italiano di Tecnologia, Materials Characterization, Via Morego 30, 16163 Genova, Italy
| | - Giammarino Pugliese
- Istituto
Italiano di Tecnologia, Nanochemistry, Via Morego 30, 16163 Genova, Italy
| | - Filippo Drago
- Istituto
Italiano di Tecnologia, Nanochemistry, Via Morego 30, 16163 Genova, Italy
| | | | - Michele Balsamo
- Kayser
Italia S.r.l., Via di
Popogna 501, 57128 Livorno, Italy
| | - Valfredo Zolesi
- Kayser
Italia S.r.l., Via di
Popogna 501, 57128 Livorno, Italy
| | - Gianni Ciofani
- Istituto
Italiano di Tecnologia, Smart Bio-Interfaces, Viale Rinaldo Piaggio 34, 56025 Pontedera (Pisa), Italy
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12
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Speacht TL, Lang CH, Donahue HJ. Soluble RANKL exaggerates hindlimb suspension-induced osteopenia but not muscle protein balance. J Orthop Res 2021; 39:1860-1869. [PMID: 33222219 PMCID: PMC8140066 DOI: 10.1002/jor.24917] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Revised: 11/02/2020] [Accepted: 11/19/2020] [Indexed: 02/04/2023]
Abstract
We examined the hypothesis that exaggerating unloading-induced bone loss using a combination of hindlimb suspension (HLS) and exogenous injections of receptor activator of nuclear factor-κB ligand (RANKL) also exaggerates gastrocnemius and quadriceps muscle loss. Forty, male C57Bl/6J mice (16 weeks) were subjected to HLS or normal ambulation (ground control, GC) for 14 days. Mice received three intraperitoneal injections of either human recombinant soluble RANKL or phosphate-buffered saline as control (n = 10/group) at 24 h intervals starting on Day 1 of HLS. GC + RANKL and HLS mice exhibited similar decreases in trabecular bone volume and density in both proximal tibias and distal femurs. However, RANKL affected trabecular number, separation, and connectivity density, while HLS decreased trabecular thickness. The combination of RANKL and HLS exacerbated these changes. Similarly, GC + RANKL and HLS mice saw comparable decreases in cortical bone volume, thickness, and strength in femur midshafts, and combination treatment exacerbated these changes. Plasma concentrations of P1NP were increased in both groups receiving RANKL, while CTX concentrations were unchanged. HLS decreased gastrocnemius weight and was associated with a reduction in global protein synthesis, and no change in proteasome activity. This change was correlated with a decrease in S6K1 and S6 phosphorylation, but no change in 4E-BP1 phosphorylation. Injection of RANKL did not alter gastrocnemius or quadriceps muscle protein metabolism in GC or HLS mice. Our results suggest that injection of soluble RANKL exacerbates unloading-induced bone loss, but not unloading-induced gastrocnemius or quadriceps muscle loss.
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Affiliation(s)
- Toni L. Speacht
- Department of Orthopaedics and Rehabilitation, The Pennsylvania State University, College of Medicine, Hershey, Pennsylvania, USA
| | - Charles H. Lang
- Department of Cellular and Molecular Physiology, The Pennsylvania State University, College of Medicine, Hershey, Pennsylvania, USA
| | - Henry J. Donahue
- Department of Orthopaedics and Rehabilitation, The Pennsylvania State University, College of Medicine, Hershey, Pennsylvania, USA,Department of Biomedical Engineering, Virginia Commonwealth University, Richmond, Virginia, USA
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13
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Zhang S, Ueno D, Ohira T, Kato H, Izawa T, Yamanouchi S, Yoshida Y, Takahashi A, Ohira Y. Depression of Bone Density at the Weight-Bearing Joints in Wistar Hannover Rats by a Simulated Mechanical Stress Associated With Partial Gravity Environment. Front Cell Dev Biol 2021; 9:707470. [PMID: 34381788 PMCID: PMC8352372 DOI: 10.3389/fcell.2021.707470] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Accepted: 06/29/2021] [Indexed: 11/13/2022] Open
Abstract
The partial gravity environment in space can negatively affect bone health. This survey aimed to study the reaction of different parts of the lower limb bones of rats to partial gravity and the effects of different degrees of gravity on these bony parts. We used 15 8-week-old male Wistar Hannover rats were used at the beginning of the experiment. The degree of mechanical stress was modified, but the ankle joint was maintained at ∼30°, ∼120°, or ∼160° with or without plaster fixation during 10-day hindlimb suspension. Computed tomography was performed to measure the bone parameters [bone mineral density (BMD), trabecular BMD, cortical BMD, and cortical thickness] of each studied group of the whole, proximal, middle, and distal femur and distal tibia. BMD, trabecular BMD, and cortical thickness of the distal femur and proximal tibia of the simulated mechanical stress associated with partial gravity groups were significantly lower than those of the control group; the effect of different degrees of gravity on the same area of hindlimb bone had no significant difference. The simulated mechanical stress associated with partial gravity had the most significant effect on the bone close to the knee joint, with the largest weight-bearing response.
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Affiliation(s)
- Shenke Zhang
- Gunma University Heavy Ion Medical Center, Maebashi, Japan
| | - Daishin Ueno
- Graduate School of Science and Technology, Nara Institute of Science and Technology, Ikoma, Japan
| | - Takashi Ohira
- Research Center for Space and Medical Sciences, Doshisha University, Kyotanabe, Japan.,Organization for Research Initiatives and Development, Doshisha University, Kyotanabe, Japan.,Department of Physiology and Regenerative Medicine, Kindai University Faculty of Medicine, Osakasayama, Japan
| | - Hisashi Kato
- Research Center for Space and Medical Sciences, Doshisha University, Kyotanabe, Japan.,Organization for Research Initiatives and Development, Doshisha University, Kyotanabe, Japan
| | - Tetsuya Izawa
- Research Center for Space and Medical Sciences, Doshisha University, Kyotanabe, Japan.,Graduate School of Health and Sports Science, Doshisha University, Kyotanabe, Japan
| | | | - Yukari Yoshida
- Gunma University Heavy Ion Medical Center, Maebashi, Japan
| | | | - Yoshinobu Ohira
- Research Center for Space and Medical Sciences, Doshisha University, Kyotanabe, Japan.,Organization for Research Initiatives and Development, Doshisha University, Kyotanabe, Japan
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14
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Smith K, Mercuri J. Microgravity and Radiation Effects on Astronaut Intervertebral Disc Health. Aerosp Med Hum Perform 2021; 92:342-352. [PMID: 33875067 DOI: 10.3357/amhp.5713.2021] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
INTRODUCTION: The effects of spaceflight on the intervertebral disc (IVD) have not been thoroughly studied, despite the knowledge that spaceflight increases the risk of herniation of IVDs in astronauts upon return to Earth. However, as long duration missions become more common, fully characterizing the mechanisms behind space-induced IVD degeneration becomes increasingly imperative for mission success. This review therefore surveys current literature to outline the results of human, animal, and cell-level studies investigating the effect of microgravity and radiation exposure on IVD health. Overall, recurring study findings include increases in IVD height in microgravity conditions, upregulation of catabolic proteases leading to a weakening extracellular matrix (ECM), and both nucleus pulposus (NP) swelling and loss of annulus fibrosus (AF) fiber alignment which are hypothesized to contribute to the increased risk of herniation when reloading is experienced. However, the limitations of current studies are also discussed. For example, human studies do not allow for invasive measures of the underpinning biochemical mechanisms, correlating animal model results to the human condition may be difficult, and cellular studies lack incorporation of ECM and other complexities that mimic the native IVD microarchitecture and environment. Moving forward, the use of three-dimensional organoid culture models that incorporate IVD-specific human cells, ECM, and signals as well as the development of cell- and ECM-level computational models may further improve our understanding of the impacts that spaceflight has on astronaut IVD health.Smith K, Mercuri J. Microgravity and radiation effects on astronaut intervertebral disc health. Aerosp Med Hum Perform. 2021; 92(5):342352.
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15
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Willey JS, Britten RA, Blaber E, Tahimic CG, Chancellor J, Mortreux M, Sanford LD, Kubik AJ, Delp MD, Mao XW. The individual and combined effects of spaceflight radiation and microgravity on biologic systems and functional outcomes. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART C, TOXICOLOGY AND CARCINOGENESIS 2021; 39:129-179. [PMID: 33902391 PMCID: PMC8274610 DOI: 10.1080/26896583.2021.1885283] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Both microgravity and radiation exposure in the spaceflight environment have been identified as hazards to astronaut health and performance. Substantial study has been focused on understanding the biology and risks associated with prolonged exposure to microgravity, and the hazards presented by radiation from galactic cosmic rays (GCR) and solar particle events (SPEs) outside of low earth orbit (LEO). To date, the majority of the ground-based analogues (e.g., rodent or cell culture studies) that investigate the biology of and risks associated with spaceflight hazards will focus on an individual hazard in isolation. However, astronauts will face these challenges simultaneously Combined hazard studies are necessary for understanding the risks astronauts face as they travel outside of LEO, and are also critical for countermeasure development. The focus of this review is to describe biologic and functional outcomes from ground-based analogue models for microgravity and radiation, specifically highlighting the combined effects of radiation and reduced weight-bearing from rodent ground-based tail suspension via hind limb unloading (HLU) and partial weight-bearing (PWB) models, although in vitro and spaceflight results are discussed as appropriate. The review focuses on the skeletal, ocular, central nervous system (CNS), cardiovascular, and stem cells responses.
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Affiliation(s)
| | | | - Elizabeth Blaber
- Department of Biomedical Engineering, Rensselaer Polytechnic Institute
| | | | | | - Marie Mortreux
- Department of Neurology, Harvard Medical School, Beth Israel Deaconess Medical Center
| | - Larry D. Sanford
- Department of Radiation Oncology, Eastern Virginia Medical School
| | - Angela J. Kubik
- Department of Biomedical Engineering, Rensselaer Polytechnic Institute
| | - Michael D. Delp
- Department of Nutrition, Food and Exercise Sciences, Florida State University
| | - Xiao Wen Mao
- Division of Biomedical Engineering Sciences (BMES), Department of Basic Sciences, Loma Linda University
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16
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Mechanical loading recovers bone but not muscle lost during unloading. NPJ Microgravity 2020; 6:36. [PMID: 33298965 PMCID: PMC7712877 DOI: 10.1038/s41526-020-00126-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Accepted: 10/16/2020] [Indexed: 01/21/2023] Open
Abstract
Space travel and prolonged bed rest are examples of mechanical unloading that induce significant muscle and bone loss. The compromised structure and function of bone and muscle owing to unloading make the reloading period a high risk for injury. To explore interactions between skeletal bone and muscle during reloading, we hypothesized that acute external mechanical loading of bone in combination with re-ambulation facilitates the proportional recovery of bone and muscle lost during hind limb suspension (HLS) unloading. Adult male C57Bl/6J mice were randomly assigned to a HLS or time-matched ground control (GC) group. After 2-weeks of HLS, separate groups of mice were studied at day 14 (no re-ambulation), day 28 (14 days re-ambulation) and day 56 (42 days re-ambulation); throughout the re-ambulation period, one limb received compressive mechanical loading and the contralateral limb served as an internal control. HLS induced loss of trabecular bone volume (BV/TV; -51 ± 2%) and muscle weight (-15 ± 2%) compared to GC at day 14. At day 28, the left tibia (re-ambulation only) of HLS mice had recovered approximately 20% of BV/TV lost during HLS, while the right tibia (re-ambulation and acute external mechanical loading) recovered to GC values of BV/TV (~100% recovery). At day 56, the right tibia continued to recover bone for some outcomes (trabecular BV/TV, trabecular thickness), while the left limb did not. Cortical bone displayed a delayed response to HLS, with a 10% greater decrease in BV/TV at day 28 compared to day 14. In contrast to bone, acute external mechanical loading during the re-ambulation period did not significantly increase muscle mass or protein synthesis in the gastrocnemius, compared to re-ambulation alone. Our results suggest acute external mechanical loading facilitates the recovery of bone during reloading following HLS unloading, but this does not translate to a concomitant recovery of muscle mass.
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17
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Schreurs AS, Torres S, Truong T, Moyer EL, Kumar A, Tahimic CGT, Alwood JS, Globus RK. Skeletal tissue regulation by catalase overexpression in mitochondria. Am J Physiol Cell Physiol 2020; 319:C734-C745. [PMID: 32783660 DOI: 10.1152/ajpcell.00068.2020] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Accumulation of oxidative damage from excess reactive oxygen species (ROS) may contribute to skeletal aging and mediate adverse responses to physiological challenges. Wild-type (WT) mice and transgenic mice (male, 16 wk of age) with human catalase targeted to the mitochondria (mCAT) were analyzed for skeletal responses to the remodeling stimuli of combined hind-limb unloading and exposure to ionizing radiation (137Cs, 2 Gy). Treatment for 2 wk caused lipid peroxidation in the bones WT but not mCAT mice, showing that transgene expression mitigated oxidative stress. Ex vivo osteoblast colony growth rate was 95% greater in mCAT than WT mice and correlated with catalase activity levels (P < 0.005, r = 0.67), although terminal osteoblast and osteoclast differentiation were unaffected. mCAT mice had lower cancellous bone volume and cortical size than WT mice. Ambulatory control mCAT animals also displayed reduced cancellous and cortical structural properties compared with control WT mice. In mCAT but not WT mice, treatment caused an unexpectedly rapid radial expansion (+8% cortical area, +22% moment of inertia), reminiscent of compensatory bone growth during advancing age. In contrast, treatment caused similar structural deficits in cancellous tissue of mCAT and WT mice. In sum, mitochondrial ROS signaling via H2O2 was important for the acquisition of adult bone structure and catalase overexpression failed to protect cancellous tissue from treatment. In contrast, catabolic stimuli caused radial expansion in mCAT not WT mice, suggesting that mitochondrial ROS in skeletal cells act to suppress tissue turnover in response to remodeling challenges.
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Affiliation(s)
- Ann-Sofie Schreurs
- Space Biosciences Division, NASA Ames Research Center, Moffett Field, California.,Universities Space Research Association, Moffett Field, California
| | - Samantha Torres
- Space Biosciences Division, NASA Ames Research Center, Moffett Field, California.,Blue Marble Space Institute of Science, Seattle, Washington
| | - Tiffany Truong
- Space Biosciences Division, NASA Ames Research Center, Moffett Field, California.,Blue Marble Space Institute of Science, Seattle, Washington
| | - Eric L Moyer
- Space Biosciences Division, NASA Ames Research Center, Moffett Field, California.,Blue Marble Space Institute of Science, Seattle, Washington
| | - Akhhilesh Kumar
- Space Biosciences Division, NASA Ames Research Center, Moffett Field, California.,Universities Space Research Association, Moffett Field, California
| | - Candice G T Tahimic
- Space Biosciences Division, NASA Ames Research Center, Moffett Field, California.,KBR, Moffett Field, California
| | - Joshua S Alwood
- Space Biosciences Division, NASA Ames Research Center, Moffett Field, California
| | - Ruth K Globus
- Space Biosciences Division, NASA Ames Research Center, Moffett Field, California
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18
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Farley A, Gnyubkin V, Vanden-Bossche A, Laroche N, Neefs M, Baatout S, Baselet B, Vico L, Mastrandrea C. Unloading-Induced Cortical Bone Loss is Exacerbated by Low-Dose Irradiation During a Simulated Deep Space Exploration Mission. Calcif Tissue Int 2020; 107:170-179. [PMID: 32451574 DOI: 10.1007/s00223-020-00708-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Accepted: 05/14/2020] [Indexed: 01/08/2023]
Abstract
Spaceflight-induced bone losses have been reliably reproduced in Hind-Limb-Unloading (HLU) rodent models. However, a considerable knowledge gap exists regarding the effects of low-dose radiation and microgravity together. Ten-week-old male C57BL/6J mice, randomly allocated to Control (CONT), Hind-Limb Unloading (HLU), and Hind-Limb Unloading plus Irradiation (HLUIR), were acclimatized at 28 °C, close to thermoneutral temperature, for 28 days prior to the 14-day HLU protocol. HLUIR mice received a 25 mGy dose of X-ray irradiation, simulating 14 days of exposure to the deep space radiation environment, on day 7 of the HLU protocol. Trabecular bone mass was similarly reduced in HLU and HLUIR mice when compared to CONT, with losses driven by osteoclastic bone resorption rather than changes to osteoblastic bone formation. Femoral cortical thickness was reduced only in the HLUIR mice (102 μm, 97.5-107) as compared to CONT (108.5 μm, 102.5-120.5). Bone surface area was also reduced only in the HLUIR group, with no difference between HLU and CONT. Cortical losses were driven by osteoclastic resorption on the posterior endosteal surface of the distal femoral diaphysis, with no increase in the numbers of dead osteocytes. In conclusion, we show that low-dose radiation exposure negatively influences bone physiology beyond that induced by microgravity alone.
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Affiliation(s)
- Antoine Farley
- INSERM U1059-SAINBIOSE, Université de Lyon, 10 rue de la Marandière, 42270, Saint-Priest-en-Jarez, France
| | - Vasily Gnyubkin
- INSERM U1059-SAINBIOSE, Université de Lyon, 10 rue de la Marandière, 42270, Saint-Priest-en-Jarez, France
| | - Arnaud Vanden-Bossche
- INSERM U1059-SAINBIOSE, Université de Lyon, 10 rue de la Marandière, 42270, Saint-Priest-en-Jarez, France
| | - Norbert Laroche
- INSERM U1059-SAINBIOSE, Université de Lyon, 10 rue de la Marandière, 42270, Saint-Priest-en-Jarez, France
| | - Mieke Neefs
- SCK CEN, Radiobiology Unit, Boeretang 200, 2400, Mol, Belgium
| | - Sarah Baatout
- SCK CEN, Radiobiology Unit, Boeretang 200, 2400, Mol, Belgium
| | - Bjorn Baselet
- SCK CEN, Radiobiology Unit, Boeretang 200, 2400, Mol, Belgium
| | - Laurence Vico
- INSERM U1059-SAINBIOSE, Université de Lyon, 10 rue de la Marandière, 42270, Saint-Priest-en-Jarez, France.
| | - Carmelo Mastrandrea
- INSERM U1059-SAINBIOSE, Université de Lyon, 10 rue de la Marandière, 42270, Saint-Priest-en-Jarez, France
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19
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Bai J, Wang Y, Wang J, Zhai J, He F, Zhu G. Irradiation-induced senescence of bone marrow mesenchymal stem cells aggravates osteogenic differentiation dysfunction via paracrine signaling. Am J Physiol Cell Physiol 2020; 318:C1005-C1017. [PMID: 32233952 DOI: 10.1152/ajpcell.00520.2019] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The role of cellular senescence induced by radiation in bone loss has attracted much attention. As one of the common complications of anticancer radiotherapy, irradiation-induced bone deterioration is common and clinically significant, but the pathological mechanism has not been elucidated. This study was performed to explore the cellular senescence and senescence-associated secretory phenotype (SASP) induction of bone marrow-derived mesenchymal stem cells (BMSCs) by irradiation and its role in osteogenic differentiation dysfunction. It was observed that irradiated BMSCs lost typical fibroblast-like morphology, exhibited suppressed viability and differentiation potential accompanied with senescence phenotypes, including an increase in senescence-associated β-galactosidase (SA-β-gal) staining-positive cells, and upregulated senescence-related genes p53/p21, whereas no changes happened to p16. Additionally, DNA damage γ-H2AX foci, G0/G1 phase of cell cycle arrest, and cellular and mitochondrial reactive oxygen species (ROS) increased in an irradiation dose-dependent manner. Meanwhile, the JAK1/STAT3 pathway was activated and accompanied by an increase in SASP secretion, such as IL-6, IL-8, and matrix metalloproteinase-9 (MMP9), whereas 0.8 μM JAK1 inhibitor (JAKi) treatment effectively inhibited the JAK pathway and SASP production. Furthermore, conditioned medium (CM) from irradiation-induced senescent (IRIS) BMSCs exhibited a markedly reduced ability in osteogenic differentiation and marker gene expression of osteoblasts, whereas CM with JAKi intervention may effectively improve these deterioration effects. In conclusion, irradiation could provoke BMSC senescence and SASP secretion and further aggravate osteogenic differentiation dysfunction via paracrine signaling, whereas SASP targeting may be a possible intervention strategy for alleviating irradiation-induced bone loss.
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Affiliation(s)
- Jiangtao Bai
- Department of Radiation Health, Institute of Radiation Medicine, Fudan University, Shanghai, China
| | - Yuyang Wang
- Department of Radiation Health, Institute of Radiation Medicine, Fudan University, Shanghai, China
| | - Jianping Wang
- Department of Radiation Health, Institute of Radiation Medicine, Fudan University, Shanghai, China
| | - Jianglong Zhai
- Department of Radiation Health, Institute of Radiation Medicine, Fudan University, Shanghai, China
| | - Feilong He
- Department of Radiation Health, Institute of Radiation Medicine, Fudan University, Shanghai, China
| | - Guoying Zhu
- Department of Radiation Health, Institute of Radiation Medicine, Fudan University, Shanghai, China
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20
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Johnson D, Lawrence SE, Livingston EW, Hienz RD, Davis CM, Lau AG. Modeling Space Radiation Induced Bone Changes in Rat Femurs through Finite Element Analysis. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2019; 2018:1763-1766. [PMID: 30440736 DOI: 10.1109/embc.2018.8512620] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
As the duration of manned missions outside of the Earth's protective shielding increase, astronauts are at risk for exposure to space radiation. Various organ systems may be damaged due to exposure. This study investigates the bone strength changes using finite element modeling of Long Evans rats (n=85) subjected to graded, head-only proton (0, 10, 25, and 100 cGy, 150 MeV/n) and 28silicon (0, 10, 25, and 50 cGy, 300 MeV/n) radiation. The strength of the femoral neck will be examined due its clinical relevance to hip fractures. It has been shown in previous studies that bone mineral density was not reduced at the site of fracture. These findings question whether measurements of bone mineral density may be used to assess risk of hip fracture. The mechanisms leading to the irregular relationship between bone density and strength are still uncertain within literature and investigated to greater extent in clinical applications. Finite element analysis within this study simulated physiological loading of the femoral neck. No significant changes in femoral neck strength were found across doses of proton or 28silicon head-only radiation. Future work includes performing mechanical testing of the bone samples. Moving from mouse to larger animal models may also provide the increased lifespan for assessing the long-term outcomes of radiation exposure.
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21
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Tahimic CGT, Paul AM, Schreurs AS, Torres SM, Rubinstein L, Steczina S, Lowe M, Bhattacharya S, Alwood JS, Ronca AE, Globus RK. Influence of Social Isolation During Prolonged Simulated Weightlessness by Hindlimb Unloading. Front Physiol 2019; 10:1147. [PMID: 31572207 PMCID: PMC6753329 DOI: 10.3389/fphys.2019.01147] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2019] [Accepted: 08/22/2019] [Indexed: 12/15/2022] Open
Abstract
The hindlimb unloading (HU) model has been used extensively to simulate the cephalad fluid shift and musculoskeletal disuse observed in spaceflight with its application expanding to study immune, cardiovascular and central nervous system responses, among others. Most HU studies are performed with singly housed animals, although social isolation also can substantially impact behavior and physiology, and therefore may confound HU experimental results. Other HU variants that allow for paired housing have been developed although no systematic assessment has been made to understand the effects of social isolation on HU outcomes. Hence, we aimed to determine the contribution of social isolation to tissue responses to HU. To accomplish this, we developed a refinement to the traditional NASA Ames single housing HU system to accommodate social housing in pairs, retaining desirable features of the original design. We conducted a 30-day HU experiment with adult, female mice that were either singly or socially housed. HU animals in both single and social housing displayed expected musculoskeletal deficits versus housing matched, normally loaded (NL) controls. However, select immune and hypothalamic-pituitary-adrenal (HPA) axis responses were differentially impacted by the HU social environment relative to matched NL controls. HU led to a reduction in % CD4+ T cells in singly housed, but not in socially housed mice. Unexpectedly, HU increased adrenal gland mass in socially housed but not singly housed mice, while social isolation increased adrenal gland mass in NL controls. HU also led to elevated plasma corticosterone levels at day 30 in both singly and socially housed mice. Thus, musculoskeletal responses to simulated weightlessness are similar regardless of social environment with a few differences in adrenal and immune responses. Our findings show that combined stressors can mask, not only exacerbate, select responses to HU. These findings further expand the utility of the HU model for studying possible combined effects of spaceflight stressors.
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Affiliation(s)
- Candice G T Tahimic
- Space Biosciences Division, NASA Ames Research Center, Moffett Field, CA, United States.,KBR, Houston, TX, United States
| | - Amber M Paul
- Space Biosciences Division, NASA Ames Research Center, Moffett Field, CA, United States.,Universities Space Research Association, Columbia, MD, United States
| | - Ann-Sofie Schreurs
- Space Biosciences Division, NASA Ames Research Center, Moffett Field, CA, United States.,KBR, Houston, TX, United States
| | - Samantha M Torres
- Space Biosciences Division, NASA Ames Research Center, Moffett Field, CA, United States.,Blue Marble Space Institute of Science, Seattle, WA, United States
| | - Linda Rubinstein
- Space Biosciences Division, NASA Ames Research Center, Moffett Field, CA, United States.,Universities Space Research Association, Columbia, MD, United States
| | - Sonette Steczina
- Space Biosciences Division, NASA Ames Research Center, Moffett Field, CA, United States.,Blue Marble Space Institute of Science, Seattle, WA, United States
| | - Moniece Lowe
- Space Biosciences Division, NASA Ames Research Center, Moffett Field, CA, United States.,Blue Marble Space Institute of Science, Seattle, WA, United States
| | - Sharmila Bhattacharya
- Space Biosciences Division, NASA Ames Research Center, Moffett Field, CA, United States
| | - Joshua S Alwood
- Space Biosciences Division, NASA Ames Research Center, Moffett Field, CA, United States
| | - April E Ronca
- Space Biosciences Division, NASA Ames Research Center, Moffett Field, CA, United States.,Department of Obstetrics and Gynecology, Wake Forest School of Medicine, Winston-Salem, NC, United States
| | - Ruth K Globus
- Space Biosciences Division, NASA Ames Research Center, Moffett Field, CA, United States
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22
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Chandra A, Park SS, Pignolo RJ. Potential role of senescence in radiation-induced damage of the aged skeleton. Bone 2019; 120:423-431. [PMID: 30543989 DOI: 10.1016/j.bone.2018.12.006] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Revised: 12/04/2018] [Accepted: 12/08/2018] [Indexed: 12/21/2022]
Abstract
Human aging-related changes are exacerbated in cases of disease and cancer, and conversely aging is a catalyst for the occurrence of disease and multimorbidity. For example, old age is the most significant risk factor for cancer and among people who suffer from cancer, >60% are above the age of 65. Oxidative stress and DNA damage, leading to genomic instability and telomere dysfunction, are prevalent in aging and radiation-induced damage and are major cellular events that lead to senescence. Human exposures from nuclear fallout, cosmic radiation and clinical radiotherapy (RT) are some common sources of irradiation that affect bone tissue. RT has been used to treat malignant tumors for over a century, but the effects of radiation damage on tumor-adjacent normal tissue has largely been overlooked. There is an increase in the percent survivorship among patients post-RT, and it is in older survivors where the deleterious synergy between aging and radiation exposure conspires to promote tissue deterioration and dysfunction which then negatively impacts their quality of life. Thus, an aging skeleton is already pre-disposed to architectural deterioration, which is further worsened by radiation-induced bone damage. Effects of senescence and the senescence associated secretory phenotype (SASP) have been implicated in age-associated bone loss, but their roles in radiation-associated bone damage are still elusive. RT is used in treatment for a variety of cancers and in different anatomical locations, the sequelae of which include long-term morbidity and lifelong discomfort. Therefore, consideration of the growing evidence that implicates the role of senescence in radiation-induced bone damage argues in favor of exploiting current senotherapeutic approaches as a possible prevention or treatment.
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Affiliation(s)
- Abhishek Chandra
- Department of Medicine, Mayo Clinic School of Medicine, Mayo Clinic, Rochester, MN, USA; Department of Physiology and Biomedical Engineering, Mayo Clinic School of Medicine, Mayo Clinic, Rochester, MN, USA.
| | - Sean S Park
- Department of Radiation Oncology, Mayo Clinic School of Medicine, Mayo Clinic, Rochester, MN, USA
| | - Robert J Pignolo
- Department of Medicine, Mayo Clinic School of Medicine, Mayo Clinic, Rochester, MN, USA; Department of Physiology and Biomedical Engineering, Mayo Clinic School of Medicine, Mayo Clinic, Rochester, MN, USA.
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23
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Bevelacqua JJ, Mortazavi SMJ. Comments on "Irradiation effects of MeV protons on dry and hydrated Brassica rapa seeds". LIFE SCIENCES IN SPACE RESEARCH 2018; 19:51. [PMID: 30482281 DOI: 10.1016/j.lssr.2018.09.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Accepted: 09/10/2018] [Indexed: 06/09/2023]
Affiliation(s)
- J J Bevelacqua
- Bevelacqua Resources, 343 Adair Drive, Richland, WA 99352, USA
| | - S M J Mortazavi
- Diagnostic Imaging Department, Fox Chase Cancer Center, 333 Cottman Avenue, Philadelphia, PA 19111, USA; Ionizing and Non-Ionizing Radiation Protection Research Center (INIRPRC), Shiraz University of Medical Sciences, Shiraz, Iran.
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24
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Shanmugarajan S, Zhang Y, Moreno-Villanueva M, Clanton R, Rohde LH, Ramesh GT, Sibonga JD, Wu H. Combined Effects of Simulated Microgravity and Radiation Exposure on Osteoclast Cell Fusion. Int J Mol Sci 2017; 18:ijms18112443. [PMID: 29156538 PMCID: PMC5713410 DOI: 10.3390/ijms18112443] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2017] [Revised: 11/12/2017] [Accepted: 11/15/2017] [Indexed: 12/11/2022] Open
Abstract
The loss of bone mass and alteration in bone physiology during space flight are one of the major health risks for astronauts. Although the lack of weight bearing in microgravity is considered a risk factor for bone loss and possible osteoporosis, organisms living in space are also exposed to cosmic radiation and other environmental stress factors. As such, it is still unclear as to whether and by how much radiation exposure contributes to bone loss during space travel, and whether the effects of microgravity and radiation exposure are additive or synergistic. Bone is continuously renewed through the resorption of old bone by osteoclast cells and the formation of new bone by osteoblast cells. In this study, we investigated the combined effects of microgravity and radiation by evaluating the maturation of a hematopoietic cell line to mature osteoclasts. RAW 264.7 monocyte/macrophage cells were cultured in rotating wall vessels that simulate microgravity on the ground. Cells under static 1g or simulated microgravity were exposed to γ rays of varying doses, and then cultured in receptor activator of nuclear factor-κB ligand (RANKL) for the formation of osteoclast giant multinucleated cells (GMCs) and for gene expression analysis. Results of the study showed that radiation alone at doses as low as 0.1 Gy may stimulate osteoclast cell fusion as assessed by GMCs and the expression of signature genes such as tartrate resistant acid phosphatase (Trap) and dendritic cell-specific transmembrane protein (Dcstamp). However, osteoclast cell fusion decreased for doses greater than 0.5 Gy. In comparison to radiation exposure, simulated microgravity induced higher levels of cell fusion, and the effects of these two environmental factors appeared additive. Interestingly, the microgravity effect on osteoclast stimulatory transmembrane protein (Ocstamp) and Dcstamp expressions was significantly higher than the radiation effect, suggesting that radiation may not increase the synthesis of adhesion molecules as much as microgravity.
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Affiliation(s)
- Srinivasan Shanmugarajan
- NASA Johnson Space Center, Houston, TX 77058, USA.
- Department of Biological and Environmental Sciences, University of Houston Clear Lake, Houston, TX 77058, USA.
| | - Ye Zhang
- NASA Kennedy Space Center, Cape Canaveral, FL 32899, USA.
| | - Maria Moreno-Villanueva
- NASA Johnson Space Center, Houston, TX 77058, USA.
- Department of Biology, University of Konstanz, 78457 Konstanz, Germany.
| | - Ryan Clanton
- Department of Nuclear Engineering, Texas A & M University, College Station, TX 77843, USA.
| | - Larry H Rohde
- Department of Biological and Environmental Sciences, University of Houston Clear Lake, Houston, TX 77058, USA.
| | | | | | - Honglu Wu
- NASA Johnson Space Center, Houston, TX 77058, USA.
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25
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Alwood JS, Tran LH, Schreurs AS, Shirazi-Fard Y, Kumar A, Hilton D, Tahimic CGT, Globus RK. Dose- and Ion-Dependent Effects in the Oxidative Stress Response to Space-Like Radiation Exposure in the Skeletal System. Int J Mol Sci 2017; 18:ijms18102117. [PMID: 28994728 PMCID: PMC5666799 DOI: 10.3390/ijms18102117] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2017] [Revised: 09/29/2017] [Accepted: 09/30/2017] [Indexed: 12/12/2022] Open
Abstract
Space radiation may pose a risk to skeletal health during subsequent aging. Irradiation acutely stimulates bone remodeling in mice, although the long-term influence of space radiation on bone-forming potential (osteoblastogenesis) and possible adaptive mechanisms are not well understood. We hypothesized that ionizing radiation impairs osteoblastogenesis in an ion-type specific manner, with low doses capable of modulating expression of redox-related genes. 16-weeks old, male, C57BL6/J mice were exposed to low linear-energy-transfer (LET) protons (150 MeV/n) or high-LET 56Fe ions (600 MeV/n) using either low (5 or 10 cGy) or high (50 or 200 cGy) doses at NASA's Space Radiation Lab. Five weeks or one year after irradiation, tissues were harvested and analyzed by microcomputed tomography for cancellous microarchitecture and cortical geometry. Marrow-derived, adherent cells were grown under osteoblastogenic culture conditions. Cell lysates were analyzed by RT-PCR during the proliferative or mineralizing phase of growth, and differentiation was analyzed by imaging mineralized nodules. As expected, a high dose (200 cGy), but not lower doses, of either 56Fe or protons caused a loss of cancellous bone volume/total volume. Marrow cells produced mineralized nodules ex vivo regardless of radiation type or dose; 56Fe (200 cGy) inhibited osteoblastogenesis by more than 90% (5 weeks and 1 year post-IR). After 5 weeks, irradiation (protons or 56Fe) caused few changes in gene expression levels during osteoblastogenesis, although a high dose 56Fe (200 cGy) increased Catalase and Gadd45. The addition of exogenous superoxide dismutase (SOD) protected marrow-derived osteoprogenitors from the damaging effects of exposure to low-LET (137Cs γ) when irradiated in vitro, but had limited protective effects on high-LET 56Fe-exposed cells. In sum, either protons or 56Fe at a relatively high dose (200 cGy) caused persistent bone loss, whereas only high-LET 56Fe increased redox-related gene expression, albeit to a limited extent, and inhibited osteoblastogenesis. Doses below 50 cGy did not elicit widespread responses in any parameter measured. We conclude that high-LET irradiation at 200 cGy impaired osteoblastogenesis and regulated steady-state gene expression of select redox-related genes during osteoblastogenesis, which may contribute to persistent bone loss.
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Affiliation(s)
- Joshua S Alwood
- Bone and Signaling Laboratory, Space BioSciences Division, NASA Ames Research Center, Mail-Stop 236-7, Moffett Field, CA 94035, USA.
| | - Luan H Tran
- Bone and Signaling Laboratory, Space BioSciences Division, NASA Ames Research Center, Mail-Stop 236-7, Moffett Field, CA 94035, USA.
| | - Ann-Sofie Schreurs
- Bone and Signaling Laboratory, Space BioSciences Division, NASA Ames Research Center, Mail-Stop 236-7, Moffett Field, CA 94035, USA.
| | - Yasaman Shirazi-Fard
- Bone and Signaling Laboratory, Space BioSciences Division, NASA Ames Research Center, Mail-Stop 236-7, Moffett Field, CA 94035, USA.
| | - Akhilesh Kumar
- Bone and Signaling Laboratory, Space BioSciences Division, NASA Ames Research Center, Mail-Stop 236-7, Moffett Field, CA 94035, USA.
| | - Diane Hilton
- Bone and Signaling Laboratory, Space BioSciences Division, NASA Ames Research Center, Mail-Stop 236-7, Moffett Field, CA 94035, USA.
| | - Candice G T Tahimic
- Bone and Signaling Laboratory, Space BioSciences Division, NASA Ames Research Center, Mail-Stop 236-7, Moffett Field, CA 94035, USA.
- Wyle Laboratories, Mail-Stop 236-7, Moffett Field, CA 94035, USA.
| | - Ruth K Globus
- Bone and Signaling Laboratory, Space BioSciences Division, NASA Ames Research Center, Mail-Stop 236-7, Moffett Field, CA 94035, USA.
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