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Zhao HW, Zhao J, Hu LN, Liang JN, Shi YY, Nie C, Qiu CY, Nan XS, Li YX, Gao FL, Liu Y, Dong Y, Luo L. Effect of long-term weightlessness on retina and optic nerve in tail-suspension rats. Int J Ophthalmol 2016; 9:825-30. [PMID: 27366682 DOI: 10.18240/ijo.2016.06.06] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Accepted: 04/29/2016] [Indexed: 11/23/2022] Open
Abstract
AIM To evaluate the effect of long-term weightlessness on retina and optic nerve in tail-suspension (TS) rats. METHODS A stimulated weightlessness model was established by suspending rats' tail. After 12wk, the ultrastructure and the number of optic nerve axons were observed by transmission electron microscope. The number of survival retinal ganglion cells (RGCs) was calculated by fluorescent gold retrograde labeling. Retina cells apoptosis was detected by TUNEL staining. The function of optic nerve and retina was evaluated by the visual evoked potential (VEP) and oscillatory potentials (Ops). RESULTS The optic nerve axons were swollen and sparsely aligned, and the lamellar separation and myelin disintegration occurred after 12wk in TS rats. The density of optic nerve axons was 32.23±3.92 (vs 37.43±4.13, P=0.0145), the RGCs density was 1645±46 cells/mm(2) (vs 1867±54 cells/mm(2) P=0.0000), the incidence rate of retinal cells apoptosis was 5.38%±0.53% (vs 4.75%±0.54%, P=0.0238), the amplitude of VEP-P100 was 15.43±2.14 µV (vs 17.67±2.17 µV, P=0.0424), the latency of VEP-P100 was 69.05±5.34ms (vs 62.43±4.87ms P=0.0143) and the sum amplitude of Ops was 81.05±8.34 µV (vs 91.67±10.21 µV, P=0.0280) in TS group and the control group, respectively. CONCLUSION Long-term weightlessness can induce the ultrastructural changes and functional depress of the optic nerve, as well as retinal cell damages in TS rats.
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Affiliation(s)
- Hong-Wei Zhao
- Chinese PLA General Hospital, Beijing 100039, China; Department of Ophthalmology, the 306th Hospital of PLA, Beijing 100101, China
| | - Jun Zhao
- Department of Ophthalmology, the 306th Hospital of PLA, Beijing 100101, China
| | - Lian-Na Hu
- Department of Ophthalmology, the 306th Hospital of PLA, Beijing 100101, China
| | - Jing-Nan Liang
- Institute of Microbiology, Chinese Academy of Science, Beijing 100101, China
| | - Yuan-Yuan Shi
- Department of Ophthalmology, the 306th Hospital of PLA, Beijing 100101, China
| | - Chuang Nie
- Department of Ophthalmology, the 306th Hospital of PLA, Beijing 100101, China
| | - Chang-Yu Qiu
- Department of Ophthalmology, the 306th Hospital of PLA, Beijing 100101, China
| | - Xin-Shuai Nan
- Anhui Medical University, Hefei 230000, Anhui Province, China
| | - Yu-Xin Li
- Department of Ophthalmology, the 306th Hospital of PLA, Beijing 100101, China; Third Military Medical University, Chongqing 400038, China
| | - Fu-Lin Gao
- Department of Ophthalmology, the 306th Hospital of PLA, Beijing 100101, China
| | - Yi Liu
- Department of Ophthalmology, the 306th Hospital of PLA, Beijing 100101, China
| | - Yu Dong
- The First hospital of Jilin University, Changchun 130021, Jilin Province, China
| | - Ling Luo
- Department of Ophthalmology, the 306th Hospital of PLA, Beijing 100101, China
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Sridharan DM, Asaithamby A, Blattnig SR, Costes SV, Doetsch PW, Dynan WS, Hahnfeldt P, Hlatky L, Kidane Y, Kronenberg A, Naidu MD, Peterson LE, Plante I, Ponomarev AL, Saha J, Snijders AM, Srinivasan K, Tang J, Werner E, Pluth JM. Evaluating biomarkers to model cancer risk post cosmic ray exposure. LIFE SCIENCES IN SPACE RESEARCH 2016; 9:19-47. [PMID: 27345199 PMCID: PMC5613937 DOI: 10.1016/j.lssr.2016.05.004] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Accepted: 05/11/2016] [Indexed: 06/06/2023]
Abstract
Robust predictive models are essential to manage the risk of radiation-induced carcinogenesis. Chronic exposure to cosmic rays in the context of the complex deep space environment may place astronauts at high cancer risk. To estimate this risk, it is critical to understand how radiation-induced cellular stress impacts cell fate decisions and how this in turn alters the risk of carcinogenesis. Exposure to the heavy ion component of cosmic rays triggers a multitude of cellular changes, depending on the rate of exposure, the type of damage incurred and individual susceptibility. Heterogeneity in dose, dose rate, radiation quality, energy and particle flux contribute to the complexity of risk assessment. To unravel the impact of each of these factors, it is critical to identify sensitive biomarkers that can serve as inputs for robust modeling of individual risk of cancer or other long-term health consequences of exposure. Limitations in sensitivity of biomarkers to dose and dose rate, and the complexity of longitudinal monitoring, are some of the factors that increase uncertainties in the output from risk prediction models. Here, we critically evaluate candidate early and late biomarkers of radiation exposure and discuss their usefulness in predicting cell fate decisions. Some of the biomarkers we have reviewed include complex clustered DNA damage, persistent DNA repair foci, reactive oxygen species, chromosome aberrations and inflammation. Other biomarkers discussed, often assayed for at longer points post exposure, include mutations, chromosome aberrations, reactive oxygen species and telomere length changes. We discuss the relationship of biomarkers to different potential cell fates, including proliferation, apoptosis, senescence, and loss of stemness, which can propagate genomic instability and alter tissue composition and the underlying mRNA signatures that contribute to cell fate decisions. Our goal is to highlight factors that are important in choosing biomarkers and to evaluate the potential for biomarkers to inform models of post exposure cancer risk. Because cellular stress response pathways to space radiation and environmental carcinogens share common nodes, biomarker-driven risk models may be broadly applicable for estimating risks for other carcinogens.
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Affiliation(s)
| | | | - Steve R Blattnig
- Langley Research Center, Langley Research Center (LaRC), VA, United States
| | - Sylvain V Costes
- Lawrence Berkeley National Laboratory, Berkeley, CA, United States
| | | | | | | | - Lynn Hlatky
- CCSB-Tufts School of Medicine, Boston, MA, United States
| | - Yared Kidane
- Wyle Science, Technology & Engineering Group, Houston, TX, United States
| | - Amy Kronenberg
- Lawrence Berkeley National Laboratory, Berkeley, CA, United States
| | - Mamta D Naidu
- CCSB-Tufts School of Medicine, Boston, MA, United States
| | - Leif E Peterson
- Houston Methodist Research Institute, Houston, TX, United States
| | - Ianik Plante
- Wyle Science, Technology & Engineering Group, Houston, TX, United States
| | - Artem L Ponomarev
- Wyle Science, Technology & Engineering Group, Houston, TX, United States
| | - Janapriya Saha
- UT Southwestern Medical Center, Dallas, TX, United States
| | | | | | - Jonathan Tang
- Exogen Biotechnology, Inc., Berkeley, CA, United States
| | | | - Janice M Pluth
- Lawrence Berkeley National Laboratory, Berkeley, CA, United States.
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53
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Chang H, Sheng JJ, Zhang L, Yue ZJ, Jiao B, Li JS, Yu ZB. ROS-Induced Nuclear Translocation of Calpain-2 Facilitates Cardiomyocyte Apoptosis in Tail-Suspended Rats. J Cell Biochem 2016; 116:2258-69. [PMID: 25820554 DOI: 10.1002/jcb.25176] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2015] [Accepted: 03/24/2015] [Indexed: 12/21/2022]
Abstract
Isoproterenol (ISO) induced nuclear translocation of calpain-2 which further increased susceptibility of cardiomyocyte apoptosis in tail-suspended rats. The underlying mechanisms remain elusive. In the present study, the results showed that ISO (10 nM) significantly elevated NADPH oxidases (NOXs) activity and NOXs-derived ROS productions which induced nuclear translocation of calpain-2 in cardiomyocytes of tail-suspended rats. In contrast, the inhibition of NADPH oxidase or cleavage of ROS not only reduced ROS productions, but also resisted nuclear translocation of calpain-2 and decreased ISO-induced apoptosis of cardiomyocyte in tail-suspended rats. ISO also increased the constitutive binding between calpain-2 and Ca(2+)/calmodulin-dependent protein kinase II δB (CaMK II δB) in nuclei, concomitant with the promotion of CaMK II δB degradation and subsequent down-regulation of Bcl-2 mRNA expression and the ratio of Bcl-2 to Bax protein in tail-suspended rat cardiomyocytes. These effects of ISO on cardiomyocytes were abolished by a calpain inhibitor PD150606. Inhibition of calpain significantly reduced ISO-induced loss of the mitochondrial membrane potential, cytochrome c release into the cytoplasm, as well as the activation of caspase-3 and caspase-9 in mitochondrial apoptotic pathway. In summary, the above results suggest that ISO increased NOXs-derived ROS which activated nuclear translocation of calpain-2, subsequently nuclear calpain-2 degraded CaMK II δB which reduced the ratio of Bcl-2 to Bax, and finally the mitochondria apoptosis pathway was triggered in tail-suspended rat cardiomyocytes. Therefore, calpain-2 may represent a potentially therapeutic target for prevention of oxidative stress-associated cardiomyocyte apoptosis.
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Affiliation(s)
- Hui Chang
- Department of Aerospace Physiology, Fourth Military Medical University, 169 Changlexi Road, Xi'an, 710032,, China
| | - Juan-Juan Sheng
- Department of Aerospace Physiology, Fourth Military Medical University, 169 Changlexi Road, Xi'an, 710032,, China
| | | | - Zhi-Jie Yue
- Department of Aerospace Physiology, Fourth Military Medical University, 169 Changlexi Road, Xi'an, 710032,, China
| | | | - Jin-Sheng Li
- Department of Aerospace Physiology, Fourth Military Medical University, 169 Changlexi Road, Xi'an, 710032,, China
| | - Zhi-Bin Yu
- Department of Aerospace Physiology, Fourth Military Medical University, 169 Changlexi Road, Xi'an, 710032,, China
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Etheridge T, Szewczyk NJ, Zuo L, Chuang CC, Liu Z, Ward AT, Dier NL, Rotarius TR, Lalande S, Zhang X, Zhang M, Li G, Dong L, Gao F. Commentaries on Viewpoint: A call for research to assess and promote functional resilience in astronaut crews. J Appl Physiol (1985) 2016; 120:473-4. [PMID: 26879659 DOI: 10.1152/japplphysiol.01036.2015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Affiliation(s)
- Timothy Etheridge
- University of ExeterUniversity of NottinghamAssistant ProfessorThe Ohio State University College of MedicineDepartment of Kinesiology University of Toledo, OhioDept. of Aerospace Medicine Fourth Military Medical University
| | - Nathaniel J Szewczyk
- University of ExeterUniversity of NottinghamAssistant ProfessorThe Ohio State University College of MedicineDepartment of Kinesiology University of Toledo, OhioDept. of Aerospace Medicine Fourth Military Medical University
| | - Li Zuo
- University of ExeterUniversity of NottinghamAssistant ProfessorThe Ohio State University College of MedicineDepartment of Kinesiology University of Toledo, OhioDept. of Aerospace Medicine Fourth Military Medical University
| | - Chia-Chen Chuang
- University of ExeterUniversity of NottinghamAssistant ProfessorThe Ohio State University College of MedicineDepartment of Kinesiology University of Toledo, OhioDept. of Aerospace Medicine Fourth Military Medical University
| | - Zewen Liu
- University of ExeterUniversity of NottinghamAssistant ProfessorThe Ohio State University College of MedicineDepartment of Kinesiology University of Toledo, OhioDept. of Aerospace Medicine Fourth Military Medical University
| | - A T Ward
- University of ExeterUniversity of NottinghamAssistant ProfessorThe Ohio State University College of MedicineDepartment of Kinesiology University of Toledo, OhioDept. of Aerospace Medicine Fourth Military Medical University
| | - N L Dier
- University of ExeterUniversity of NottinghamAssistant ProfessorThe Ohio State University College of MedicineDepartment of Kinesiology University of Toledo, OhioDept. of Aerospace Medicine Fourth Military Medical University
| | - T R Rotarius
- University of ExeterUniversity of NottinghamAssistant ProfessorThe Ohio State University College of MedicineDepartment of Kinesiology University of Toledo, OhioDept. of Aerospace Medicine Fourth Military Medical University
| | - S Lalande
- University of ExeterUniversity of NottinghamAssistant ProfessorThe Ohio State University College of MedicineDepartment of Kinesiology University of Toledo, OhioDept. of Aerospace Medicine Fourth Military Medical University
| | - Xing Zhang
- University of ExeterUniversity of NottinghamAssistant ProfessorThe Ohio State University College of MedicineDepartment of Kinesiology University of Toledo, OhioDept. of Aerospace Medicine Fourth Military Medical University
| | - Min Zhang
- University of ExeterUniversity of NottinghamAssistant ProfessorThe Ohio State University College of MedicineDepartment of Kinesiology University of Toledo, OhioDept. of Aerospace Medicine Fourth Military Medical University
| | - Guohua Li
- University of ExeterUniversity of NottinghamAssistant ProfessorThe Ohio State University College of MedicineDepartment of Kinesiology University of Toledo, OhioDept. of Aerospace Medicine Fourth Military Medical University
| | - Ling Dong
- University of ExeterUniversity of NottinghamAssistant ProfessorThe Ohio State University College of MedicineDepartment of Kinesiology University of Toledo, OhioDept. of Aerospace Medicine Fourth Military Medical University
| | - Feng Gao
- University of ExeterUniversity of NottinghamAssistant ProfessorThe Ohio State University College of MedicineDepartment of Kinesiology University of Toledo, OhioDept. of Aerospace Medicine Fourth Military Medical University
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55
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Globus RK, Morey-Holton E. Hindlimb unloading: rodent analog for microgravity. J Appl Physiol (1985) 2016; 120:1196-206. [PMID: 26869711 DOI: 10.1152/japplphysiol.00997.2015] [Citation(s) in RCA: 142] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2015] [Accepted: 02/02/2016] [Indexed: 11/22/2022] Open
Abstract
The rodent hindlimb unloading (HU) model was developed in the 1980s to make it possible to study mechanisms, responses, and treatments for the adverse consequences of spaceflight. Decades before development of the HU model, weightlessness was predicted to yield deficits in the principal tissues responsible for structure and movement on Earth, primarily muscle and bone. Indeed, results from early spaceflight and HU experiments confirmed the expected sensitivity of the musculoskeletal system to gravity loading. Results from human and animal spaceflight and HU experiments show that nearly all organ systems and tissues studied display some measurable changes, albeit sometimes minor and of uncertain relevance to astronaut health. The focus of this review is to examine key HU results for various organ systems including those related to stress; the immune, cardiovascular, and nervous systems; vision changes; and wound healing. Analysis of the validity of the HU model is important given its potential value for both hypothesis testing and countermeasure development.
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Affiliation(s)
- Ruth K Globus
- Space Biosciences Division, NASA-Ames Research Center, Moffett Field, California
| | - Emily Morey-Holton
- Space Biosciences Division, NASA-Ames Research Center, Moffett Field, California
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56
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Wang Y, Javed I, Liu Y, Lu S, Peng G, Zhang Y, Qing H, Deng Y. Effect of Prolonged Simulated Microgravity on Metabolic Proteins in Rat Hippocampus: Steps toward Safe Space Travel. J Proteome Res 2015; 15:29-37. [PMID: 26523826 DOI: 10.1021/acs.jproteome.5b00777] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Mitochondria are not only the main source of energy in cells but also produce reactive oxygen species (ROS), which result in oxidative stress when in space. This oxidative stress is responsible for energy imbalances and cellular damage. In this study, a rat tail suspension model was used in individual experiments for 7 and 21 days to explore the effect of simulated microgravity (SM) on metabolic proteins in the hippocampus, a vital brain region involved in learning, memory, and navigation. A comparative (18)O-labeled quantitative proteomic strategy was used to observe the differential expression of metabolic proteins. Forty-two and sixty-seven mitochondrial metabolic proteins were differentially expressed after 21 and 7 days of SM, respectively. Mitochondrial Complex I, III, and IV, isocitrate dehydrogenase and malate dehydrogenase were down-regulated. Moreover, DJ-1 and peroxiredoxin 6, which defend against oxidative damage, were up-regulated in the hippocampus. Western blot analysis of proteins DJ-1 and COX 5A confirmed the mass spectrometry results. Despite these changes in mitochondrial protein expression, no obvious cell apoptosis was observed after 21 days of SM. The results of this study indicate that the oxidative stress induced by SM has profound effects on metabolic proteins.
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Affiliation(s)
- Yun Wang
- School of Life Sciences, Beijing Institute of Technology , No. 5 Zhongguancun South Street, Beijing 100081, P.R. China
| | - Iqbal Javed
- School of Life Sciences, Beijing Institute of Technology , No. 5 Zhongguancun South Street, Beijing 100081, P.R. China
| | - Yahui Liu
- School of Life Sciences, Beijing Institute of Technology , No. 5 Zhongguancun South Street, Beijing 100081, P.R. China
| | - Song Lu
- School of Life Sciences, Beijing Institute of Technology , No. 5 Zhongguancun South Street, Beijing 100081, P.R. China
| | - Guang Peng
- School of Life Sciences, Beijing Institute of Technology , No. 5 Zhongguancun South Street, Beijing 100081, P.R. China
| | - Yongqian Zhang
- School of Life Sciences, Beijing Institute of Technology , No. 5 Zhongguancun South Street, Beijing 100081, P.R. China
| | - Hong Qing
- School of Life Sciences, Beijing Institute of Technology , No. 5 Zhongguancun South Street, Beijing 100081, P.R. China
| | - Yulin Deng
- School of Life Sciences, Beijing Institute of Technology , No. 5 Zhongguancun South Street, Beijing 100081, P.R. China
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Gao Y, Li S, Xu D, Wang J, Sun Y. Changes in apoptotic microRNA and mRNA expression profiling in Caenorhabditis elegans during the Shenzhou-8 mission. JOURNAL OF RADIATION RESEARCH 2015; 56:872-82. [PMID: 26286471 PMCID: PMC4628221 DOI: 10.1093/jrr/rrv050] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2015] [Accepted: 07/21/2015] [Indexed: 05/07/2023]
Abstract
Radiation and microgravity exposure have been proven to induce abnormal apoptosis in microRNA (miRNA) and mRNA expression, but whether space conditions, including radiation and microgravity, activate miRNAs to regulate the apoptosis is undetermined. For that purpose, we investigated miRNome and mRNA expression in the ced-1 Caenorhabditis elegans mutant vs the wild-type, both of which underwent spaceflight, spaceflight 1g-centrifuge control and ground control conditions during the Shenzhou-8 mission. Results showed that no morphological changes in the worms were detected, but differential miRNA expression increased from 43 (ground control condition) to 57 and 91 in spaceflight and spaceflight control conditions, respectively. Microgravity altered miRNA expression profiling by decreasing the number and significance of differentially expressed miRNA compared with 1 g incubation during spaceflight. Alterations in the miRNAs were involved in alterations in apoptosis, neurogenesis larval development, ATP metabolism and GTPase-mediated signal transduction. Among these, 17 altered miRNAs potentially involved in apoptosis were screened and showed obviously different expression signatures between space conditions. By integrated analysis of miRNA and mRNA, miR-797 and miR-81 may be involved in apoptosis by targeting the genes ced-10 and both drp-1 and hsp-1, respectively. Compared with ground condition, space conditions regulated apoptosis though a different manner on transcription, by altering expression of seven core apoptotic genes in spaceflight condition, and eight in spaceflight control condition. Results indicate that, miRNA of Caenorhabditis elegans probably regulates apoptotic gene expression in response to space environmental stress, and shows different behavior under microgravity condition compared with 1 g condition in the presence of space radiation.
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Affiliation(s)
- Ying Gao
- Institute of Environmental Systems Biology, College of Environmental Science and Engineering, Dalian Maritime University, Linghai Road 1, Dalian 116026, China
| | - Shuai Li
- Institute of Environmental Systems Biology, College of Environmental Science and Engineering, Dalian Maritime University, Linghai Road 1, Dalian 116026, China
| | - Dan Xu
- Institute of Environmental Systems Biology, College of Environmental Science and Engineering, Dalian Maritime University, Linghai Road 1, Dalian 116026, China
| | - Junjun Wang
- Institute of Environmental Systems Biology, College of Environmental Science and Engineering, Dalian Maritime University, Linghai Road 1, Dalian 116026, China
| | - Yeqing Sun
- Institute of Environmental Systems Biology, College of Environmental Science and Engineering, Dalian Maritime University, Linghai Road 1, Dalian 116026, China
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Murata Y, Yasuda T, Watanabe-Asaka T, Oda S, Mantoku A, Takeyama K, Chatani M, Kudo A, Uchida S, Suzuki H, Tanigaki F, Shirakawa M, Fujisawa K, Hamamoto Y, Terai S, Mitani H. Histological and Transcriptomic Analysis of Adult Japanese Medaka Sampled Onboard the International Space Station. PLoS One 2015; 10:e0138799. [PMID: 26427061 PMCID: PMC4591011 DOI: 10.1371/journal.pone.0138799] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Accepted: 09/03/2015] [Indexed: 11/20/2022] Open
Abstract
To understand how humans adapt to the space environment, many experiments can be conducted on astronauts as they work aboard the Space Shuttle or the International Space Station (ISS). We also need animal experiments that can apply to human models and help prevent or solve the health issues we face in space travel. The Japanese medaka (Oryzias latipes) is a suitable model fish for studying space adaptation as evidenced by adults of the species having mated successfully in space during 15 days of flight during the second International Microgravity Laboratory mission in 1994. The eggs laid by the fish developed normally and hatched as juveniles in space. In 2012, another space experiment (“Medaka Osteoclast”) was conducted. Six-week-old male and female Japanese medaka (Cab strain osteoblast transgenic fish) were maintained in the Aquatic Habitat system for two months in the ISS. Fish of the same strain and age were used as the ground controls. Six fish were fixed with paraformaldehyde or kept in RNA stabilization reagent (n = 4) and dissected for tissue sampling after being returned to the ground, so that several principal investigators working on the project could share samples. Histology indicated no significant changes except in the ovary. However, the RNA-seq analysis of 5345 genes from six tissues revealed highly tissue-specific space responsiveness after a two-month stay in the ISS. Similar responsiveness was observed among the brain and eye, ovary and testis, and the liver and intestine. Among these six tissues, the intestine showed the highest space response with 10 genes categorized as oxidation–reduction processes (gene ontogeny term GO:0055114), and the expression levels of choriogenin precursor genes were suppressed in the ovary. Eleven genes including klf9, klf13, odc1, hsp70 and hif3a were upregulated in more than four of the tissues examined, thus suggesting common immunoregulatory and stress responses during space adaptation.
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Affiliation(s)
- Yasuhiko Murata
- Department of Radiation Biology, Graduate School of Medicine, Tohoku University, Miyagi, Japan
| | - Takako Yasuda
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Chiba, Japan
| | - Tomomi Watanabe-Asaka
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Chiba, Japan
| | - Shoji Oda
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Chiba, Japan
| | - Akiko Mantoku
- Department of Biological Information, Graduated School of Bioscience and Biotechnology, Tokyo Institute of Technology, Kanagawa, Japan
| | - Kazuhiro Takeyama
- Department of Biological Information, Graduated School of Bioscience and Biotechnology, Tokyo Institute of Technology, Kanagawa, Japan
| | - Masahiro Chatani
- Department of Biological Information, Graduated School of Bioscience and Biotechnology, Tokyo Institute of Technology, Kanagawa, Japan
| | - Akira Kudo
- Department of Biological Information, Graduated School of Bioscience and Biotechnology, Tokyo Institute of Technology, Kanagawa, Japan
| | | | | | | | | | - Koichi Fujisawa
- Department of Gastroenterology and Hepatology, Yamaguchi University Graduate School of Medicine, Yamaguchi, Japan
| | - Yoshihiko Hamamoto
- Department of Biomolecular Engineering, Graduate School of Medicine, Yamaguchi University, Yamaguchi, Japan
| | - Shuji Terai
- Division of Gastroenterology and Hepatology, Graduate School of Medical and Dental Sciences, Niigata University, Niigata, Japan
- * E-mail: (HM); (ST)
| | - Hiroshi Mitani
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Chiba, Japan
- * E-mail: (HM); (ST)
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Ishihara A, Nagatomo F, Terada M, Fujino H, Kondo H, Ishioka N. Effects of microgravity on the mouse triceps brachii muscle. Muscle Nerve 2015; 52:63-8. [PMID: 25307981 DOI: 10.1002/mus.24491] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2014] [Revised: 09/28/2014] [Accepted: 10/10/2014] [Indexed: 12/13/2022]
Abstract
INTRODUCTION In this study we investigated the effects of microgravity on the fiber properties of the mouse triceps brachii, a forelimb muscle that has no antigravity function. METHODS Mice (n = 7) were exposed to microgravity for 13 days on the space shuttle Atlantis (Space Transportation System-135). The fiber cross-sectional area (CSA) and succinate dehydrogenase (SDH) staining intensity of the triceps brachii muscle were compared with those of controls (n = 7). SDH activity in this muscle was also estimated. RESULTS Microgravity did not affect the body weight, muscle weight, or fiber CSA, but there was reduced SDH staining intensity of all types of fibers, irrespective of the muscle region (P < 0.05). Microgravity also reduced muscle SDH activity (P < 0.05). CONCLUSIONS Short-term exposure to microgravity induced a decrease in oxidative capacity, but not atrophy, in the triceps brachii muscle of mice.
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Affiliation(s)
- Akihiko Ishihara
- Laboratory of Cell Biology and Life Science, Graduate School of Human and Environmental Studies, Kyoto University, Kyoto, 606-8501, Japan
| | - Fumiko Nagatomo
- Laboratory of Cell Biology and Life Science, Graduate School of Human and Environmental Studies, Kyoto University, Kyoto, 606-8501, Japan
| | - Masahiro Terada
- Department of Cell Biology, Jikei University School of Medicine, Tokyo, Japan
| | - Hidemi Fujino
- Department of Rehabilitation Science, Kobe University Graduate School of Health Sciences, Kobe, Japan
| | - Hiroyo Kondo
- Department of Food Sciences and Nutrition, Nagoya Women's University, Nagoya, Japan
| | - Noriaki Ishioka
- Department of Interdisciplinary Science, Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Japan
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Chen L, Zong R, Zhou J, Ge L, Zhou T, Ma JX, Liu Z, Zhou Y. The oxidant role of 4-hydroxynonenal in corneal epithelium. Sci Rep 2015; 5:10630. [PMID: 26023743 PMCID: PMC4448499 DOI: 10.1038/srep10630] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2014] [Accepted: 04/22/2015] [Indexed: 11/12/2022] Open
Abstract
4-Hydroxynonenal (4-HNE or HNE) is a main endogenous product of cellular lipid peroxidation in tissues and is reported to play pathogenic roles in eye diseases. Here we investigated the association between 4-HNE and oxidative stress in the corneal epithelium. 4-HNE suppressed the cell viability of human corneal epithelial cells (HCE) in a concentration dependent manner. 4-HNE significantly increased the level of 3-Nitrotyrosine (3-NT), a marker of oxidative stress, in HCE cells and corneal epithelium of rats by immunofluorescent staining and Western blot analysis. To its underlying mechanistic on ROS system, 4-HNE elevated the ROS generation enzyme NADPH oxidase 4 (NOX4) and induced the activation of NF-E2–related factor-2 (NRF2) and its downstream effectors: NAD(P)H dehydrogenase (quinone 1) (NQO1) and glutathione S-transferase P (GSTP). Furthermore, N-acetylcysteine (NAC), an antioxidant and ROS scavenger, antagonized the inhibitory and oxidant effects of 4-HNE on the corneal epithelial cells. In conclusion, 4-HNE plays an oxidant role in the corneal epithelium and this work provides a new strategy for the pathogenesis and treatment of corneal diseases.
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Affiliation(s)
- Longlong Chen
- Eye Institute and affiliated Xiamen Eye Center of Xiamen University, Fujian Provincial Key Laboratory of Ophthalmology and Visual Science, Xiamen, Fujian, 361005, PR China
| | - Rongrong Zong
- Eye Institute and affiliated Xiamen Eye Center of Xiamen University, Fujian Provincial Key Laboratory of Ophthalmology and Visual Science, Xiamen, Fujian, 361005, PR China
| | - Jing Zhou
- Eye Institute and affiliated Xiamen Eye Center of Xiamen University, Fujian Provincial Key Laboratory of Ophthalmology and Visual Science, Xiamen, Fujian, 361005, PR China
| | - Lianping Ge
- Eye Institute and affiliated Xiamen Eye Center of Xiamen University, Fujian Provincial Key Laboratory of Ophthalmology and Visual Science, Xiamen, Fujian, 361005, PR China
| | - Tong Zhou
- Eye Institute and affiliated Xiamen Eye Center of Xiamen University, Fujian Provincial Key Laboratory of Ophthalmology and Visual Science, Xiamen, Fujian, 361005, PR China
| | - Jian-xing Ma
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104, USA
| | - Zuguo Liu
- Eye Institute and affiliated Xiamen Eye Center of Xiamen University, Fujian Provincial Key Laboratory of Ophthalmology and Visual Science, Xiamen, Fujian, 361005, PR China
| | - Yueping Zhou
- Eye Institute and affiliated Xiamen Eye Center of Xiamen University, Fujian Provincial Key Laboratory of Ophthalmology and Visual Science, Xiamen, Fujian, 361005, PR China
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Post-Spaceflight (STS-135) Mouse Splenocytes Demonstrate Altered Activation Properties and Surface Molecule Expression. PLoS One 2015; 10:e0124380. [PMID: 25970640 PMCID: PMC4430214 DOI: 10.1371/journal.pone.0124380] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2015] [Accepted: 03/02/2015] [Indexed: 11/19/2022] Open
Abstract
Alterations in immune function have been documented during or post-spaceflight and in ground based models of microgravity. Identification of immune parameters that are dysregulated during spaceflight is an important step in mitigating crew health risks during deep space missions. The in vitro analysis of leukocyte activity post-spaceflight in both human and animal species is primarily focused on lymphocytic function. This report completes a broader spectrum analysis of mouse lymphocyte and monocyte changes post 13 days orbital flight (mission STS-135). Analysis includes an examination in surface markers for cell activation, and antigen presentation and co-stimulatory molecules. Cytokine production was measured after stimulation with T-cell mitogen or TLR-2, TLR-4, or TLR-5 agonists. Splenocyte surface marker analysis immediate post-spaceflight and after in vitro culture demonstrated unique changes in phenotypic populations between the flight mice and matched treatment ground controls. Post-spaceflight splenocytes (flight splenocytes) had lower expression intensity of CD4+CD25+ and CD8+CD25+ cells, lower percentage of CD11c+MHC II+ cells, and higher percentage of CD11c+MHC I+ populations compared to ground controls. The flight splenocytes demonstrated an increase in phagocytic activity. Stimulation with ConA led to decrease in CD4+ population but increased CD4+CD25+ cells compared to ground controls. Culturing with TLR agonists led to a decrease in CD11c+ population in splenocytes isolated from flight mice compared to ground controls. Consequently, flight splenocytes with or without TLR-agonist stimulation showed a decrease in CD11c+MHC I+, CD11c+MHC II+, and CD11c+CD86+ cells compared to ground controls. Production of IFN-γ was decreased and IL-2 was increased from ConA stimulated flight splenocytes. This study demonstrated that expression of surface molecules can be affected by conditions of spaceflight and impaired responsiveness persists under culture conditions in vitro.
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Carozzo S, Ball SL, Narici L, Schardt D, Sannita WG. Interaction of (12)C ions with the mouse retinal response to light. Neurosci Lett 2015; 598:36-40. [PMID: 25956035 DOI: 10.1016/j.neulet.2015.04.048] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2014] [Revised: 04/01/2015] [Accepted: 04/29/2015] [Indexed: 10/23/2022]
Abstract
Astronauts in orbit reported phosphenes varying in shape and orientation across the visual field; incidence was correlated with the radiation flux. Patients with skull tumors treated by (12)C ions and volunteers whose posterior portion of the eye was exposed to highly ionizing particles in early studies reported comparable percepts. An origin in radiation activating the visual system is suggested. Bursts (∼ 4 ms) of (12)C ions evoked electrophysiological mass responses comparable to those to light in the retina of anesthetized wild-type mice at threshold flux intensities consistent with the incidence observed in humans. The retinal response amplitude increased in mice with ion intensity to a maximum at ∼ 2000 ions/burst, to decline at higher intensities; the inverted-U relationship suggests complex effects on retinal structures. Here, we show that bursts of (12)C ions presented simultaneously to white light stimuli reduced the presynaptic mass response to light in the mouse retina, while increasing the postsynaptic retinal and cortical responses amplitude and the phase-locking to stimulus of cortical low frequency and gamma (∼ 25-45 Hz) responses. These findings suggest (12)C ions to interfere with, rather than mimicking the light action on photoreceptors; a parallel action on other retinal structures/mechanisms resulting in cortical activation is conceivable. Electrophysiological visual testing appears applicable to monitor the radiation effects and in designing countermeasures to prevent functional visual impairment during operations in space.
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Affiliation(s)
- Simone Carozzo
- Department of Neuroscience, Ophthalmology and Genetics, University, Genova, Italy
| | - Sherry L Ball
- Cleveland VA Medical Center, Cole Eye Institute, Cleveland Clinic Foundation, Cleveland, OH, USA
| | - Livio Narici
- Department of Physics, University Tor Vergata, and INFN, Roma2, Roma, Italy
| | - Dieter Schardt
- Biophysik, GSI Helmholtzzentrum für Schwerionenforschung GmbH, Darmstadt, FRG Germany
| | - Walter G Sannita
- Department of Neuroscience, Ophthalmology and Genetics, University, Genova, Italy; Department of Psychiatry, State University of New York, Stony Brook, NY, USA.
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63
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Christofidou-Solomidou M, Pietrofesa RA, Arguiri E, Schweitzer KS, Berdyshev EV, McCarthy M, Corbitt A, Alwood JS, Yu Y, Globus RK, Solomides CC, Ullrich RL, Petrache I. Space radiation-associated lung injury in a murine model. Am J Physiol Lung Cell Mol Physiol 2014; 308:L416-28. [PMID: 25526737 DOI: 10.1152/ajplung.00260.2014] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Despite considerable progress in identifying health risks to crewmembers related to exposure to galactic/cosmic rays and solar particle events (SPE) during space travel, its long-term effects on the pulmonary system are unknown. We used a murine risk projection model to investigate the impact of exposure to space-relevant radiation (SR) on the lung. C3H mice were exposed to (137)Cs gamma rays, protons (acute, low-dose exposure mimicking the 1972 SPE), 600 MeV/u (56)Fe ions, or 350 MeV/u (28)Si ions at the NASA Space Radiation Laboratory at Brookhaven National Laboratory. Animals were irradiated at the age of 2.5 mo and evaluated 23.5 mo postirradiation, at 26 mo of age. Compared with age-matched nonirradiated mice, SR exposures led to significant air space enlargement and dose-dependent decreased systemic oxygenation levels. These were associated with late mild lung inflammation and prominent cellular injury, with significant oxidative stress and apoptosis (caspase-3 activation) in the lung parenchyma. SR, especially high-energy (56)Fe or (28)Si ions markedly decreased sphingosine-1-phosphate levels and Akt- and p38 MAPK phosphorylation, depleted anti-senescence sirtuin-1 and increased biochemical markers of autophagy. Exposure to SR caused dose-dependent, pronounced late lung pathological sequelae consistent with alveolar simplification and cellular signaling of increased injury and decreased repair. The associated systemic hypoxemia suggested that this previously uncharacterized space radiation-associated lung injury was functionally significant, indicating that further studies are needed to define the risk and to develop appropriate lung-protective countermeasures for manned deep space missions.
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Affiliation(s)
- Melpo Christofidou-Solomidou
- Department of Medicine, Pulmonary Allergy and Critical Care Division, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania;
| | - Ralph A Pietrofesa
- Department of Medicine, Pulmonary Allergy and Critical Care Division, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania
| | - Evguenia Arguiri
- Department of Medicine, Pulmonary Allergy and Critical Care Division, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania
| | - Kelly S Schweitzer
- Department of Medicine, Pulmonary and Critical Care Division, Indiana University School of Medicine, Indianapolis, Indiana
| | - Evgeny V Berdyshev
- Department of Medicine University of Illinois at Chicago, Chicago, Illinois
| | | | - Astrid Corbitt
- University of Texas Medical Branch (UTMB), Galveston, Texas
| | - Joshua S Alwood
- Oak Ridge Associated Universities, NASA Postdoctoral Program, Moffett Field, California
| | - Yongjia Yu
- University of Texas Medical Branch (UTMB), Galveston, Texas
| | - Ruth K Globus
- NASA Ames Research Center, Moffett Field, California
| | | | | | - Irina Petrache
- Department of Medicine, Pulmonary and Critical Care Division, Indiana University School of Medicine, Indianapolis, Indiana; Richard L. Roudebush VA Medical Center, Indianapolis, Indiana
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64
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Wheeler KT, Payne V, D'Agostino RB, Walb MC, Munley MT, Metheny-Barlow LJ, Robbins ME. Impact of breathing 100% oxygen on radiation-induced cognitive impairment. Radiat Res 2014; 182:580-5. [PMID: 25338095 DOI: 10.1667/rr13643.1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Future space missions are expected to include increased extravehicular activities (EVAs) during which astronauts are exposed to high-energy space radiation while breathing 100% oxygen. Given that brain irradiation can lead to cognitive impairment, and that oxygen is a potent radiosensitizer, there is a concern that astronauts may be at greater risk of developing cognitive impairment when exposed to space radiation while breathing 100% O(2) during an EVA. To address this concern, unanesthetized, unrestrained, young adult male Fischer 344 × Brown Norway rats were allowed to breathe 100% O(2) for 30 min prior to, during and 2 h after whole-body irradiation with 0, 1, 3, 5 or 7 Gy doses of 18 MV X rays delivered from a medical linear accelerator at a dose rate of ~425 mGy/min. Irradiated and unirradiated rats breathing air (~21% O(2)) served as controls. Cognitive function was assessed 9 months postirradiation using the perirhinal cortex-dependent novel object recognition task. Cognitive function was not impaired until the rats breathing either air or 100% O(2) received a whole-body dose of 7 Gy. However, at all doses, cognitive function of the irradiated rats breathing 100% O(2) was improved over that of the irradiated rats breathing air. These data suggest that astronauts are not at greater risk of developing cognitive impairment when exposed to space radiation while breathing 100% O(2) during an EVA.
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Affiliation(s)
- Kenneth T Wheeler
- a Department of Radiation Oncology, Wake Forest School of Medicine, Winston-Salem, North Carolina 27157
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Abstract
UNLABELLED Creation of lethal and synthetic lethal mutations in an experimental organism is a cornerstone of genetic dissection of gene function, and is related to the concept of an essential gene. Common inbred mouse strains carry background mutations, which can act as genetic modifiers, interfering with the assignment of gene essentiality. The inbred strain C57BL/6J, commonly known as "Black Six", stands out, as it carries a spontaneous homozygous deletion in the nicotinamide nucleotide transhydrogenase (Nnt) gene [GenBank: AH009385.2], resulting in impairment of steroidogenic mitochondria of the adrenal gland, and a multitude of indirect modifier effects, coming from alteration of glucocorticoid-regulated processes. Over time, the popular strain has been used, by means of gene targeting technology, to assign "essential" and "redundant" qualifiers to numerous genes, thus creating an internally consistent "parallel universe" of knowledge. It is unrealistic to suggest phasing-out of this strain, given the scope of shared resources built around it, however, continuing on the road of "strain-unawareness" will result in profound waste of effort, particularly where translational research is concerned. The review analyzes the historical roots of this phenomenon and proposes that building of "parallel universes" should be urgently made visible to a critical reader by obligatory use of unambiguous and persistent tags in publications and databases, such as hypertext links, pointing to a vendor's strain description web page, or to a digital object identifier (d.o.i.) of the original publication, so that any research done exclusively in C57BL/6J, could be easily identified. REVIEWERS This article was reviewed by Dr. Neil Smalheiser and Dr. Miguel Andrade-Navarro.
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Affiliation(s)
- Alexander Kraev
- Charles H, Best Institute, Banting and Best Department of Medical Research, University of Toronto, Toronto, Ontario M5G 1L6, Canada.
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Latchney SE, Rivera PD, Mao XW, Ferguson VL, Bateman TA, Stodieck LS, Nelson GA, Eisch AJ. The effect of spaceflight on mouse olfactory bulb volume, neurogenesis, and cell death indicates the protective effect of novel environment. J Appl Physiol (1985) 2014; 116:1593-604. [PMID: 24744382 DOI: 10.1152/japplphysiol.01174.2013] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Space missions necessitate physiological and psychological adaptations to environmental factors not present on Earth, some of which present significant risks for the central nervous system (CNS) of crewmembers. One CNS region of interest is the adult olfactory bulb (OB), as OB structure and function are sensitive to environmental- and experience-induced regulation. It is currently unknown how the OB is altered by spaceflight. In this study, we evaluated OB volume and neurogenesis in mice shortly after a 13-day flight on Space Shuttle Atlantis [Space Transport System (STS)-135] relative to two groups of control mice maintained on Earth. Mice housed on Earth in animal enclosure modules that mimicked the conditions onboard STS-135 (AEM-Ground mice) had greater OB volume relative to mice maintained in standard housing on Earth (Vivarium mice), particularly in the granule (GCL) and glomerular (GL) cell layers. AEM-Ground mice also had more OB neuroblasts and fewer apoptotic cells relative to Vivarium mice. However, the AEM-induced increase in OB volume and neurogenesis was not seen in STS-135 mice (AEM-Flight mice), suggesting that spaceflight may have negated the positive effects of the AEM. In fact, when OB volume of AEM-Flight mice was considered, there was a greater density of apoptotic cells relative to AEM-Ground mice. Our findings suggest that factors present during spaceflight have opposing effects on OB size and neurogenesis, and provide insight into potential strategies to preserve OB structure and function during future space missions.
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Affiliation(s)
- Sarah E Latchney
- Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Phillip D Rivera
- Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Xiao W Mao
- Department of Basic Sciences, Division of Radiation Research, Loma Linda University and Medical Center, Loma Linda, California
| | - Virginia L Ferguson
- Department of Mechanical Engineering, University of Colorado at Boulder, Boulder, Colorado; and
| | - Ted A Bateman
- Department of Biomedical Engineering, University of North Carolina, Chapel Hill, North Carolina
| | - Louis S Stodieck
- BioServe Space Technologies, Aerospace Engineering Sciences, University of Colorado at Boulder, Boulder, Colorado
| | - Gregory A Nelson
- Department of Basic Sciences, Division of Radiation Research, Loma Linda University and Medical Center, Loma Linda, California
| | - Amelia J Eisch
- Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, Texas;
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Pietrofesa RA, Solomides CC, Christofidou-Solomidou M. Flaxseed Mitigates Acute Oxidative Lung Damage in a Mouse Model of Repeated Radiation and Hyperoxia Exposure Associated with Space Exploration. ACTA ACUST UNITED AC 2014; 4. [PMID: 25705570 DOI: 10.4172/2161-105x.1000215] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
BACKGROUND Spaceflight missions may require crewmembers to conduct extravehicular activities (EVA). Pre-breathe protocols in preparation for an EVA entail 100% hyperoxia exposure that may last for a few hours and be repeated 2-3 times weekly. Each EVA is associated with additional challenges such as low levels of total body cosmic/galactic radiation exposure that may present a threat to crewmember health. We have developed a mouse model of total body radiation and hyperoxia exposure and identified acute damage of lung tissues. In the current study we evaluated the usefulness of dietary flaxseed (FS) as a countermeasure agent for such double-hit exposures. METHODS We evaluated lung tissue changes 2 weeks post-initiation of exposure challenges. Mouse cohorts (n=5/group) were pre-fed diets containing either 0% FS or 10% FS for 3 weeks and exposed to: a) normoxia (Untreated); b) >95% O2 (O2); c) 0.25Gy single fraction gamma radiation (IR); or d) a combination of O2 and IR (O2+IR) 3 times per week for 2 consecutive weeks, where 8-hour hyperoxia treatments were spanned by normoxic intervals. RESULTS At 2 weeks post challenge, while control-diet fed mice developed significant lung injury and inflammation across all challenges, FS protected lung tissues by decreasing bronchoalveolar lavage fluid (BALF) neutrophils (p<0.003) and protein levels, oxidative tissue damage, as determined by levels of malondialdehyde (MDA) (p<0.008) and nitrosative stress as determined by nitrite levels. Lung hydroxyproline levels, a measure of lung fibrosis, were significantly elevated in mice fed 0% FS (p<0.01) and exposed to hyperoxia/radiation or the combination treatment, but not in FS-fed mice. FS also decreased levels of a pro-inflammatory, pro-fibrogenic cytokine (TGF-β1) gene expression levels in lung. CONCLUSION Flaxseed mitigated adverse effects in lung of repeat exposures to radiation/hyperoxia. This data will provide useful information in the design of countermeasures to early tissue oxidative damage associated with space exploration.
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Affiliation(s)
- Ralph A Pietrofesa
- Department of Medicine, Pulmonary Allergy and Critical Care Division, University of Pennsylvania, Philadelphia, PA 19104, USA
| | | | - Melpo Christofidou-Solomidou
- Department of Medicine, Pulmonary Allergy and Critical Care Division, University of Pennsylvania, Philadelphia, PA 19104, USA
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