1
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Hariom SK, Nelson EJR. Cardiovascular adaptations in microgravity conditions. LIFE SCIENCES IN SPACE RESEARCH 2024; 42:64-71. [PMID: 39067992 DOI: 10.1016/j.lssr.2024.05.001] [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: 10/29/2023] [Revised: 05/13/2024] [Accepted: 05/14/2024] [Indexed: 07/30/2024]
Abstract
Gravity has had a significant impact on the evolution of life on Earth with organisms developing necessary biological adaptations over billions of years to counter this ever-existing force. There has been an exponential increase in experiments using real and simulated gravity environments in the recent years. Although an understanding followed by discovery of counter measures to negate diminished gravity in space had been the driving force of research initially, there has since been a phenomenal leap wherein a force unearthly as microgravity is beginning to show promising potential. The current review summarizes pathophysiological changes that occur in multiple aspects of the cardiovascular system when exposed to an altered gravity environment leading to cardiovascular deconditioning and orthostatic intolerance. Gravity influences not just the complex multicellular systems but even the survival of organisms at the molecular level by intervening fundamental cellular processes, directly affecting those linked to actin and microtubule organization via mechano-transduction pathways. The reach of gravity ranges from cytoskeletal rearrangement that regulates cell adhesion and migration to intracellular dynamics that dictate cell fate commitment and differentiation. An understanding that microgravity itself is not present on Earth propels the scope of simulated gravity conditions to be a unique and useful environment that could be explored for enhancing the potential of stem cells for a wide range of applications as has been highlighted here.
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Affiliation(s)
- Senthil Kumar Hariom
- Gene Therapy Laboratory, Department of Integrative Biology, School of Bio Sciences and Technology, Vellore Institute of Technology, Vellore 632 014, TN, India
| | - Everette Jacob Remington Nelson
- Gene Therapy Laboratory, Department of Integrative Biology, School of Bio Sciences and Technology, Vellore Institute of Technology, Vellore 632 014, TN, India.
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2
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van Loon JJWA, Berezovska OP, Bervoets TJM, Montufar-Solis D, Semeins CM, Zandieh-Doulabi B, Rodionova PNV, Duke J, Veldhuijzen JP. Growth and mineralization of fetal mouse long bones under microgravity and daily 1 g gravity exposure. NPJ Microgravity 2024; 10:80. [PMID: 39060264 PMCID: PMC11282293 DOI: 10.1038/s41526-024-00421-4] [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: 12/22/2023] [Accepted: 07/17/2024] [Indexed: 07/28/2024] Open
Abstract
In a previous Space Shuttle/Spacelab experiment (STS-42), we observed direct responses of isolated fetal mouse long bones to near weightlessness. This paper aimed to verify those results and study the effects of daily 1×g exposure during microgravity on the growth and mineralization of these bones. Two experiments were conducted: one on an American Space Shuttle mission (IML-2 on STS-65) and another on a Russian Bio-Cosmos flight (Bion-10 on Cosmos-2229). Despite differences in hardware, both used 17-day-old fetal mouse metatarsals cultured for 4 days. Results showed reduced proteoglycan content under microgravity compared to 1×g conditions, with no main differences in other cellular structures. While the overall metatarsal length was unaffected, the length increase of the mineralized diaphysis was significantly reduced under microgravity. Daily 1×g exposure for at least 6 h abolished the microgravity-induced reduction in cartilage mineralization, indicating the need for long-duration exposure to 1×g as an in-flight countermeasure using artificial gravity.
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Affiliation(s)
- Jack J W A van Loon
- Department of Oral Biology, Section Oral Cell Biology, ACTA-Vrije Universiteit, Amsterdam, The Netherlands.
| | - Olga P Berezovska
- Department of Radiobiology and Radioecology, Institute for Nuclear Research of National Academy of Sciences of Ukraine, Kiev, Ukraine
| | - Theodorus J M Bervoets
- Department of Oral Biology, Section Oral Cell Biology, ACTA-Vrije Universiteit, Amsterdam, The Netherlands
| | - Dina Montufar-Solis
- Department of Integrative Biology and Pharmacology, McGovern Medical School, University of Texas Health Science Center, Houston, TX, USA
| | - Cor M Semeins
- Department of Oral Biology, Section Oral Cell Biology, ACTA-Vrije Universiteit, Amsterdam, The Netherlands
| | - Behrouz Zandieh-Doulabi
- Department of Oral Biology, Section Oral Cell Biology, ACTA-Vrije Universiteit, Amsterdam, The Netherlands
| | - P Natalia V Rodionova
- Schmalhausen Institute for Zoology, National Academy of Sciences Ukraine, Kiev, Ukraine
| | - Jackie Duke
- Department of Orthodontics & Dentofacial Orthopedics, University of Texas Health Science Center, Houston, TX, USA
| | - J Paul Veldhuijzen
- Department of Oral Biology, Section Oral Cell Biology, ACTA-Vrije Universiteit, Amsterdam, The Netherlands
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3
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Rutter LA, MacKay MJ, Cope H, Szewczyk NJ, Kim J, Overbey E, Tierney BT, Muratani M, Lamm B, Bezdan D, Paul AM, Schmidt MA, Church GM, Giacomello S, Mason CE. Protective alleles and precision healthcare in crewed spaceflight. Nat Commun 2024; 15:6158. [PMID: 39039045 PMCID: PMC11263583 DOI: 10.1038/s41467-024-49423-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Accepted: 06/05/2024] [Indexed: 07/24/2024] Open
Abstract
Common and rare alleles are now being annotated across millions of human genomes, and omics technologies are increasingly being used to develop health and treatment recommendations. However, these alleles have not yet been systematically characterized relative to aerospace medicine. Here, we review published alleles naturally found in human cohorts that have a likely protective effect, which is linked to decreased cancer risk and improved bone, muscular, and cardiovascular health. Although some technical and ethical challenges remain, research into these protective mechanisms could translate into improved nutrition, exercise, and health recommendations for crew members during deep space missions.
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Affiliation(s)
- Lindsay A Rutter
- Transborder Medical Research Center, University of Tsukuba, Ibaraki, 305-8575, Japan
- Department of Genome Biology, Institute of Medicine, University of Tsukuba, Ibaraki, 305-8575, Japan
- School of Chemistry, University of Glasgow, Glasgow, G12 8QQ, UK
| | - Matthew J MacKay
- Department of Physiology and Biophysics, Weill Cornell Medicine, New York, NY, 10065, USA
- The HRH Prince Alwaleed Bin Talal Bin Abdulaziz Alsaud Institute for Computational Biomedicine, Weill Cornell Medicine, New York, NY, 10021, USA
- The WorldQuant Initiative for Quantitative Prediction, Weill Cornell Medicine, New York, NY, 10065, USA
| | - Henry Cope
- School of Medicine, University of Nottingham, Nottingham, DE22 3DT, UK
| | - Nathaniel J Szewczyk
- School of Medicine, University of Nottingham, Nottingham, DE22 3DT, UK
- Ohio Musculoskeletal and Neurological Institute (OMNI), Heritage College of Osteopathic Medicine, Ohio University, Athens, OH, 45701, USA
| | - JangKeun Kim
- Department of Physiology and Biophysics, Weill Cornell Medicine, New York, NY, 10065, USA
- The HRH Prince Alwaleed Bin Talal Bin Abdulaziz Alsaud Institute for Computational Biomedicine, Weill Cornell Medicine, New York, NY, 10021, USA
| | - Eliah Overbey
- Department of Physiology and Biophysics, Weill Cornell Medicine, New York, NY, 10065, USA
- The HRH Prince Alwaleed Bin Talal Bin Abdulaziz Alsaud Institute for Computational Biomedicine, Weill Cornell Medicine, New York, NY, 10021, USA
| | - Braden T Tierney
- Department of Physiology and Biophysics, Weill Cornell Medicine, New York, NY, 10065, USA
- The HRH Prince Alwaleed Bin Talal Bin Abdulaziz Alsaud Institute for Computational Biomedicine, Weill Cornell Medicine, New York, NY, 10021, USA
| | - Masafumi Muratani
- Transborder Medical Research Center, University of Tsukuba, Ibaraki, 305-8575, Japan
- Department of Genome Biology, Institute of Medicine, University of Tsukuba, Ibaraki, 305-8575, Japan
| | - Ben Lamm
- Colossal Biosciences, 1401 Lavaca St, Unit #155 Austin, Austin, TX, 78701, USA
| | - Daniela Bezdan
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany
- NGS Competence Center Tübingen (NCCT), University of Tübingen, Tübingen, Germany
- Yuri GmbH, Meckenbeuren, Germany
| | - Amber M Paul
- Embry-Riddle Aeronautical University, Department of Human Factors and Behavioral Neurobiology, Daytona Beach, FL, 32114, USA
| | - Michael A Schmidt
- Sovaris Aerospace, Boulder, CO, 80302, USA.
- Advanced Pattern Analysis & Human Performance Group, Boulder, CO, 80302, USA.
| | - George M Church
- GC Therapeutics Inc, Cambridge, MA, 02139, USA.
- Department of Genetics, Harvard Medical School, Boston, MA, 02115, USA.
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Cambridge, MA, 02115, USA.
| | | | - Christopher E Mason
- Department of Physiology and Biophysics, Weill Cornell Medicine, New York, NY, 10065, USA.
- The HRH Prince Alwaleed Bin Talal Bin Abdulaziz Alsaud Institute for Computational Biomedicine, Weill Cornell Medicine, New York, NY, 10021, USA.
- The WorldQuant Initiative for Quantitative Prediction, Weill Cornell Medicine, New York, NY, 10065, USA.
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Cambridge, MA, 02115, USA.
- The Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY, 10065, USA.
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4
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Tölgyesi B, Altbäcker A, Barkaszi I, Stuckenschneider T, Braunsmann L, Takács E, Ehmann B, Balázs L, Abeln V. Effect of artificial gravity on neurocognitive performance during head-down tilt bedrest. NPJ Microgravity 2024; 10:59. [PMID: 38839787 PMCID: PMC11153507 DOI: 10.1038/s41526-024-00405-4] [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: 12/20/2023] [Accepted: 05/16/2024] [Indexed: 06/07/2024] Open
Abstract
This study evaluated the acute and chronic effects of intermittent and continuous Artificial Gravity (AG) on cognitive performance during 60 days of Head-down tilt bedrest (HDTBR), a well-established ground-based spaceflight analogue method. Participants were randomly assigned to three groups: intermittent AG, continuous AG, and HDTBR control group without AG exposure. Task performance and electrophysiological measures of attention and working memory were investigated during Simple and Complex tasks in the Visual and the Auditory modality. Compared to baseline, faster reaction time and better accuracy was present during HDTBR regarding the Complex tasks, however, the practice effect was diminished in the three HDTBR groups compared to an ambulatory control group. Brain potentials showed a modality-specific decrease, as P3a was decreased only in the Auditory, while P3b decreased in the Visual modality. No evidence for acute or chronic AG-related cognitive impairments during HDTBR was found.
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Affiliation(s)
- Borbála Tölgyesi
- Institute of Cognitive Neuroscience and Psychology, HUN-REN Research Centre for Natural Sciences, Budapest, Hungary
- Interaction and Immersion Hub, Innovation Center, Moholy-Nagy University of Art and Design, Budapest, Hungary
| | - Anna Altbäcker
- Institute of Cognitive Neuroscience and Psychology, HUN-REN Research Centre for Natural Sciences, Budapest, Hungary.
| | - Irén Barkaszi
- Institute of Cognitive Neuroscience and Psychology, HUN-REN Research Centre for Natural Sciences, Budapest, Hungary
| | - Tim Stuckenschneider
- Institute of Movement and Neurosciences, Centre for Health and Integrative Physiology in Space (CHIPS), German Sport University Cologne, Cologne, Germany
- Geriatric Medicine, Department for Health, Services Research, School of Medicine and Health Sciences, Carl von Ossietzky University, Oldenburg, Germany
| | - Leonard Braunsmann
- Institute of Movement and Neurosciences, Centre for Health and Integrative Physiology in Space (CHIPS), German Sport University Cologne, Cologne, Germany
| | - Endre Takács
- Institute of Cognitive Neuroscience and Psychology, HUN-REN Research Centre for Natural Sciences, Budapest, Hungary
| | - Bea Ehmann
- Institute of Cognitive Neuroscience and Psychology, HUN-REN Research Centre for Natural Sciences, Budapest, Hungary
| | - László Balázs
- Institute of Cognitive Neuroscience and Psychology, HUN-REN Research Centre for Natural Sciences, Budapest, Hungary
| | - Vera Abeln
- Institute of Movement and Neurosciences, Centre for Health and Integrative Physiology in Space (CHIPS), German Sport University Cologne, Cologne, Germany
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5
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Zhang J, Wang X, Fu Z, Xing C, Wang Z, Yang H, Li J, Liu M, Dong L, Zhang X, Li Y, Wang J, Long J, Liu J, Wang S, Li J, Gao F. Long-term simulated microgravity fosters carotid aging-like changes via Piezo1. Cardiovasc Res 2024; 120:548-559. [PMID: 38271270 DOI: 10.1093/cvr/cvae024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Revised: 09/05/2023] [Accepted: 11/30/2023] [Indexed: 01/27/2024] Open
Abstract
AIMS Elucidating the impacts of long-term spaceflight on cardiovascular health is urgently needed in face of the rapid development of human space exploration. Recent reports including the NASA Twins Study on vascular deconditioning and aging of astronauts in spaceflight are controversial. The aims of this study were to elucidate whether long-term microgravity promotes vascular aging and the underlying mechanisms. METHODS AND RESULTS Hindlimb unloading (HU) by tail suspension was used to simulate microgravity in rats and mice. The dynamic changes of carotid stiffness in rats during 8 weeks of HU were determined. Simulated microgravity led to carotid artery aging-like changes as evidenced by increased stiffness, thickness, fibrosis, and elevated senescence biomarkers in the HU rats. Specific deletion of the mechanotransducer Piezo1 in vascular smooth muscles significantly blunted these aging-like changes in mice. Mechanistically, mechanical stretch-induced activation of Piezo1 elevated microRNA-582-5p in vascular smooth muscle cells, with resultant enhanced synthetic cell phenotype and increased collagen deposition via PTEN/PI3K/Akt signalling. Importantly, inhibition of miRNA-582-5p alleviated carotid fibrosis and stiffness not only in HU rats but also in aged rats. CONCLUSIONS Long-term simulated microgravity induces carotid aging-like changes via the mechanotransducer Piezo1-initiated and miRNA-mediated mechanism.
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MESH Headings
- Animals
- Aging/metabolism
- Aging/pathology
- Carotid Arteries/metabolism
- Carotid Arteries/pathology
- Carotid Arteries/physiopathology
- Cells, Cultured
- Disease Models, Animal
- Fibrosis
- Hindlimb Suspension
- Ion Channels/metabolism
- Ion Channels/genetics
- Mechanotransduction, Cellular/genetics
- Mice, Inbred C57BL
- Mice, Knockout
- MicroRNAs/metabolism
- MicroRNAs/genetics
- Muscle, Smooth, Vascular/metabolism
- Muscle, Smooth, Vascular/pathology
- Muscle, Smooth, Vascular/physiopathology
- Myocytes, Smooth Muscle/metabolism
- Myocytes, Smooth Muscle/pathology
- Phenotype
- Phosphatidylinositol 3-Kinases/metabolism
- Proto-Oncogene Proteins c-akt/metabolism
- PTEN Phosphohydrolase/metabolism
- PTEN Phosphohydrolase/genetics
- Rats, Sprague-Dawley
- Signal Transduction
- Time Factors
- Vascular Remodeling
- Vascular Stiffness
- Weightlessness Simulation
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Affiliation(s)
- Jiaxin Zhang
- Key Laboratory of Aerospace Medicine of Ministry of Education, School of Aerospace Medicine, Fourth Military Medical University, 169 Changlexi Road, Xi'an 710032, China
- Frontiers Science Center for Flexible Electronics, Xi'an Institute of Flexible Electronics (IFE) and Xi'an Institute of Biomedical Materials & Engineering, Northwestern Polytechnical University, Xi'an, China
| | - Xinpei Wang
- Key Laboratory of Aerospace Medicine of Ministry of Education, School of Aerospace Medicine, Fourth Military Medical University, 169 Changlexi Road, Xi'an 710032, China
| | - Zihao Fu
- Key Laboratory of Aerospace Medicine of Ministry of Education, School of Aerospace Medicine, Fourth Military Medical University, 169 Changlexi Road, Xi'an 710032, China
| | - Changyang Xing
- Key Laboratory of Aerospace Medicine of Ministry of Education, School of Aerospace Medicine, Fourth Military Medical University, 169 Changlexi Road, Xi'an 710032, China
- Department of Ultrasound Medicine, Tangdu Hospital, Fourth Military Medical University, Xi'an, China
| | - Zhen Wang
- Key Laboratory of Aerospace Medicine of Ministry of Education, School of Aerospace Medicine, Fourth Military Medical University, 169 Changlexi Road, Xi'an 710032, China
| | - Hongyan Yang
- Key Laboratory of Aerospace Medicine of Ministry of Education, School of Aerospace Medicine, Fourth Military Medical University, 169 Changlexi Road, Xi'an 710032, China
| | - Jiahui Li
- Key Laboratory of Aerospace Medicine of Ministry of Education, School of Aerospace Medicine, Fourth Military Medical University, 169 Changlexi Road, Xi'an 710032, China
| | - Meijie Liu
- Key Laboratory of Aerospace Medicine of Ministry of Education, School of Aerospace Medicine, Fourth Military Medical University, 169 Changlexi Road, Xi'an 710032, China
| | - Ling Dong
- Key Laboratory of Aerospace Medicine of Ministry of Education, School of Aerospace Medicine, Fourth Military Medical University, 169 Changlexi Road, Xi'an 710032, China
| | - Xing Zhang
- Key Laboratory of Aerospace Medicine of Ministry of Education, School of Aerospace Medicine, Fourth Military Medical University, 169 Changlexi Road, Xi'an 710032, China
| | - Yongzhi Li
- State Key Laboratory of Space Medicine, China Astronaut Research and Training Center, Beijing, China
| | - Jiaping Wang
- State Key Laboratory of Space Medicine, China Astronaut Research and Training Center, Beijing, China
| | - Jiangang Long
- Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an, China
| | - Jiankang Liu
- Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an, China
| | - Shengpeng Wang
- Cardiovascular Research Center, School of Basic Medical Sciences, Xi'an Jiaotong University, Xi'an, China
| | - Jia Li
- Key Laboratory of Aerospace Medicine of Ministry of Education, School of Aerospace Medicine, Fourth Military Medical University, 169 Changlexi Road, Xi'an 710032, China
- Key Laboratory of Hazard Assessment and Control in Special Operational Environment of Ministry of Education, School of Public Health, Fourth Military Medical University, 169 Changlexi Road, Xi'an 710032, China
| | - Feng Gao
- Key Laboratory of Aerospace Medicine of Ministry of Education, School of Aerospace Medicine, Fourth Military Medical University, 169 Changlexi Road, Xi'an 710032, China
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6
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Tays GD, Hupfeld KE, McGregor HR, Beltran NE, De Dios YE, Mulder E, Bloomberg JJ, Mulavara AP, Wood SJ, Seidler RD. Daily artificial gravity partially mitigates vestibular processing changes associated with head-down tilt bedrest. NPJ Microgravity 2024; 10:27. [PMID: 38472244 PMCID: PMC10933323 DOI: 10.1038/s41526-024-00367-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Accepted: 02/15/2024] [Indexed: 03/14/2024] Open
Abstract
Microgravity alters vestibular signaling and reduces body loading, driving sensory reweighting. The unloading effects can be modelled using head-down tilt bedrest (HDT). Artificial gravity (AG) has been hypothesized to serve as an integrated countermeasure for the declines associated with HDT and spaceflight. Here, we examined the efficacy of 30 min of daily AG to counteract brain and behavior changes from 60 days of HDT. Two groups received 30 min of AG delivered via short-arm centrifuge daily (n = 8 per condition), either in one continuous bout, or in 6 bouts of 5 min. To improve statistical power, we combined these groups (AG; n = 16). Another group served as controls in HDT with no AG (CTRL; n = 8). We examined how HDT and AG affect vestibular processing by collecting fMRI scans during vestibular stimulation. We collected these data prior to, during, and post-HDT. We assessed brain activation initially in 12 regions of interest (ROIs) and then conducted an exploratory whole brain analysis. The AG group showed no changes in activation during vestibular stimulation in a cerebellar ROI, whereas the CTRL group showed decreased activation specific to HDT. Those that received AG and showed little pre- to post-HDT changes in left vestibular cortex activation had better post-HDT balance performance. Whole brain analyses identified increased pre- to during-HDT activation in CTRLs in the right precentral gyrus and right inferior frontal gyrus, whereas AG maintained pre-HDT activation levels. These results indicate that AG could mitigate activation changes in vestibular processing that is associated with better balance performance.
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Affiliation(s)
- G D Tays
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL, USA
| | - K E Hupfeld
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL, USA
| | - H R McGregor
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL, USA
| | | | | | - E Mulder
- German Aerospace Center (DLR), Cologne, Germany
| | | | | | - S J Wood
- NASA Johnson Space Center, Houston, TX, USA
| | - R D Seidler
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL, USA.
- Norman Fixel Institute for Neurological Diseases, University of Florida, Gainesville, FL, USA.
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7
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Ino Y, Ohira T, Kumagai K, Nakai Y, Akiyama T, Moriyama K, Takeda Y, Saito T, Ryo A, Inaba Y, Hirano H, Kimura Y. Identification of mouse soleus muscle proteins altered in response to changes in gravity loading. Sci Rep 2023; 13:15768. [PMID: 37737267 PMCID: PMC10517164 DOI: 10.1038/s41598-023-42875-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Accepted: 09/15/2023] [Indexed: 09/23/2023] Open
Abstract
Gravity-dependent physical processes strongly affect the ability of elderly people to maintain musculoskeletal health by reducing muscle atrophy and increasing bone mineral density, thereby increasing quality of life. A need therefore exists to identify molecules in the musculoskeletal system that are responsive to gravitational loading and to establish an objective indicator for the maintenance of healthy musculoskeletal systems. Here, we performed an integrated assessment of the results of soleus muscle proteomic analyses in three model mouse experiments under different gravity environments (hypergravity, hindlimb unloading, and spaceflight). Myl6b, Gpd1, Fbp2, Pvalb, and Actn3 were shown to be gravity-responsive muscle proteins, and alterations in the levels of these proteins indicated changes in muscle fiber type to slow-twitch type due to gravity loading. In addition, immunoblotting and enzyme-linked immunosorbent assays revealed that Pvalb levels in the sera of hindlimb-unloaded mice and osteoporosis patients were higher than in control subjects, suggesting that Pvalb levels might be useful to objectively evaluate soleus muscle atrophy and bone loss.
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Affiliation(s)
- Yoko Ino
- Advanced Medical Research Center, Yokohama City University, Fukuura 3-9, Kanazawa-Ku, Yokohama, 236-0004, Japan
| | - Takashi Ohira
- Advanced Medical Research Center, Yokohama City University, Fukuura 3-9, Kanazawa-Ku, Yokohama, 236-0004, Japan.
- Department of Physiology and Regenerative Medicine, Kindai University Faculty of Medicine, Ohno-Higashi 377-2, Osaka-Sayama, Osaka, Japan.
| | - Ken Kumagai
- Department of Orthopaedic Surgery, Yokohama City University School of Medicine, Yokohama, Japan
| | - Yusuke Nakai
- Advanced Medical Research Center, Yokohama City University, Fukuura 3-9, Kanazawa-Ku, Yokohama, 236-0004, Japan
| | - Tomoko Akiyama
- Advanced Medical Research Center, Yokohama City University, Fukuura 3-9, Kanazawa-Ku, Yokohama, 236-0004, Japan
| | - Kayano Moriyama
- Advanced Medical Research Center, Yokohama City University, Fukuura 3-9, Kanazawa-Ku, Yokohama, 236-0004, Japan
| | - Yuriko Takeda
- Department of Biostatistics, Yokohama City University School of Medicine, Yokohama, Japan
| | | | - Akihide Ryo
- Advanced Medical Research Center, Yokohama City University, Fukuura 3-9, Kanazawa-Ku, Yokohama, 236-0004, Japan
| | - Yutaka Inaba
- Department of Orthopaedic Surgery, Yokohama City University School of Medicine, Yokohama, Japan
| | - Hisashi Hirano
- Advanced Medical Research Center, Yokohama City University, Fukuura 3-9, Kanazawa-Ku, Yokohama, 236-0004, Japan
| | - Yayoi Kimura
- Advanced Medical Research Center, Yokohama City University, Fukuura 3-9, Kanazawa-Ku, Yokohama, 236-0004, Japan.
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8
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Seidler R, Tays G, Hupfeld K, McGregor H, Beltran N, de Dios Y, Mulder E, Bloomberg J, Mulavara A, Wood S. Daily Artificial Gravity Partially Mitigates Vestibular Processing Changes Associated with Head-down Tilt Bedrest. RESEARCH SQUARE 2023:rs.3.rs-3157785. [PMID: 37502989 PMCID: PMC10371135 DOI: 10.21203/rs.3.rs-3157785/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/29/2023]
Abstract
Microgravity alters vestibular signaling and reduces body loading, driving sensory reweighting and adaptation. The unloading effects can be modelled using head down tilt bedrest (HDT). Artificial gravity (AG) has been hypothesized to serve as an integrated countermeasure for the physiological declines associated with HDT and spaceflight. Here, we examined the efficacy of 30 minutes of daily AG to counteract brain and behavior changes that arise from 60 days of HDT. One group of participants received 30 minutes of AG daily (AG; n = 16) while in HDT, and another group served as controls, spending 60 days in HDT bedrest with no AG (CTRL; n = 8). We examined how HDT and AG affect vestibular processing by collecting fMRI scans from participants as they received vestibular stimulation. We collected these data prior to, during (2x), and post HDT. We assessed brain activation initially in 10 regions of interest (ROIs) and then conducted an exploratory whole brain analysis. The AG group showed no changes in brain activation during vestibular stimulation in a cerebellar ROI, whereas the CTRL group showed decreased cerebellar activation specific to the HDT phase. Additionally, those that received AG and showed little pre- to post-bed rest changes in left OP2 activation during HDT had better post-HDT balance performance. Exploratory whole brain analyses identified increased pre- to during-HDT activation in the CTRL group in the right precentral gyrus and the right inferior frontal gyrus specific to HDT, where the AG group maintained pre-HDT activation levels. Together, these results indicate that AG could mitigate brain activation changes in vestibular processing in a manner that is associated with better balance performance after HDT.
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9
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Tays GD, Hupfeld KE, McGregor HR, Beltran NE, Kofman IS, De Dios YE, Mulder ER, Bloomberg JJ, Mulavara AP, Wood SJ, Seidler RD. Daily artificial gravity is associated with greater neural efficiency during sensorimotor adaptation. Cereb Cortex 2023; 33:8011-8023. [PMID: 36958815 PMCID: PMC10267627 DOI: 10.1093/cercor/bhad094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Revised: 02/27/2023] [Accepted: 02/28/2023] [Indexed: 03/25/2023] Open
Abstract
Altered vestibular signaling and body unloading in microgravity results in sensory reweighting and adaptation. Microgravity effects are well-replicated in head-down tilt bed rest (HDBR). Artificial gravity (AG) is a potential countermeasure to mitigate the effects of microgravity on human physiology and performance. We examined the effectiveness of daily AG for mitigating brain and/or behavioral changes in 60 days of HDBR. One group received AG for 30 minutes daily (AG; n = 16) and a control group spent the same time in HDBR but received no AG (CTRL; n = 8). All participants performed a sensorimotor adaptation task five times during fMRI scanning: twice prior to HDBR, twice during HDBR, and once following HDBR. The AG group showed similar behavioral adaptation effects compared with the CTRLs. We identified decreased brain activation in the AG group from pre to late HDBR in the cerebellum for the task baseline portion and in the thalamus, calcarine, cuneus, premotor cortices, and superior frontal gyrus in the AG group during the early adaptation phase. The two groups also exhibited differential brain-behavior correlations. Together, these results suggest that AG may result in a reduced recruitment of brain activity for basic motor processes and sensorimotor adaptation. These effects may stem from the somatosensory and vestibular stimulation that occur with AG.
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Affiliation(s)
- Grant D Tays
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL 32603, USA
| | - Kathleen E Hupfeld
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL 32603, USA
| | - Heather R McGregor
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL 32603, USA
| | | | | | | | | | | | | | - Scott J Wood
- NASA Johnson Space Center, Houston, TX 77058, USA
| | - Rachael D Seidler
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL 32603, USA
- Norman Fixel Institute for Neurological Diseases, University of Florida, Gainesville, FL 32603, USA
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10
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Freeborn TJ, Critcher S, Hooper G. Segmental Tissue Resistance of Healthy Young Adults during Four Hours of 6-Degree Head-Down-Tilt Positioning. SENSORS (BASEL, SWITZERLAND) 2023; 23:2793. [PMID: 36904995 PMCID: PMC10006931 DOI: 10.3390/s23052793] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/05/2023] [Revised: 02/27/2023] [Accepted: 03/01/2023] [Indexed: 06/18/2023]
Abstract
(1) Background: One effect of microgravity on the human body is fluid redistribution due to the removal of the hydrostatic gravitational gradient. These fluid shifts are expected to be the source of severe medical risks and it is critical to advance methods to monitor them in real-time. One technique to monitor fluid shifts captures the electrical impedance of segmental tissues, but limited research is available to evaluate if fluid shifts in response to microgravity are symmetrical due to the bilateral symmetry of the body. This study aims to evaluate this fluid shift symmetry. (2) Methods: Segmental tissue resistance at 10 kHz and 100 kHz was collected at 30 min intervals from the left/right arm, leg, and trunk of 12 healthy adults over 4 h of 6° head-down-tilt body positioning. (3) Results: Statistically significant increases were observed in the segmental leg resistances, first observed at 120 min and 90 min for 10 kHz and 100 kHz measurements, respectively. Median increases were approximately 11% to 12% for the 10 kHz resistance and 9% for the 100 kHz resistance. No statistically significant changes in the segmental arm or trunk resistance. Comparing the left and right segmental leg resistance, there were no statistically significant differences in the resistance changes based on the side of the body. (4) Conclusions: The fluid shifts induced by the 6° body position resulted in similar changes in both left and right body segments (that had statistically significant changes in this work). These findings support that future wearable systems to monitor microgravity-induced fluid shifts may only require monitoring of one side of body segments (reducing the hardware needed for the system).
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Affiliation(s)
- Todd J. Freeborn
- Department of Electrical and Computer Engineering, College of Engineering, The University of Alabama, Tuscaloosa, AL 35487, USA
| | - Shelby Critcher
- Department of Electrical and Computer Engineering, College of Engineering, The University of Alabama, Tuscaloosa, AL 35487, USA
| | - Gwendolyn Hooper
- Capstone College of Nursing, The University of Alabama, Tuscaloosa, AL 35487, USA
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11
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Li H, Wei H, Padera TP, Baish JW, Munn LL. Computational simulations of the effects of gravity on lymphatic transport. PNAS NEXUS 2022; 1:pgac237. [PMID: 36712369 PMCID: PMC9802413 DOI: 10.1093/pnasnexus/pgac237] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Accepted: 10/15/2022] [Indexed: 11/07/2022]
Abstract
Physical forces, including mechanical stretch, fluid pressure, and shear forces alter lymphatic vessel contractions and lymph flow. Gravitational forces can affect these forces, resulting in altered lymphatic transport, but the mechanisms involved have not been studied in detail. Here, we combine a lattice Boltzmann-based fluid dynamics computational model with known lymphatic mechanobiological mechanisms to investigate the movement of fluid through a lymphatic vessel under the effects of gravity that may either oppose or assist flow. Regularly spaced, mechanical bi-leaflet valves in the vessel enforce net positive flow as the vessel walls contract autonomously in response to calcium and nitric oxide (NO) levels regulated by vessel stretch and shear stress levels. We find that large gravitational forces opposing flow can stall the contractions, leading to no net flow, but transient mechanical perturbations can re-establish pumping. In the case of gravity strongly assisting flow, the contractions also cease due to high shear stress and NO production, which dilates the vessel to allow gravity-driven flow. In the intermediate range of oppositional gravity forces, the vessel actively contracts to offset nominal gravity levels or to modestly assist the favorable hydrostatic pressure gradients.
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Affiliation(s)
- Huabing Li
- Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
- Department of Material Science and Technology, Guilin University of Electronic Technology, Guilin 541004, China
| | - Huajian Wei
- Department of Material Science and Technology, Guilin University of Electronic Technology, Guilin 541004, China
| | - Timothy P Padera
- Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
| | - James W Baish
- Biomedical Engineering, Bucknell University, Lewisburg, PA 17837, USA
| | - Lance L Munn
- Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
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12
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Rabineau J, Issertine M, Hoffmann F, Gerlach D, Caiani EG, Haut B, van de Borne P, Tank J, Migeotte PF. Cardiovascular deconditioning and impact of artificial gravity during 60-day head-down bed rest—Insights from 4D flow cardiac MRI. Front Physiol 2022; 13:944587. [PMID: 36277205 PMCID: PMC9586290 DOI: 10.3389/fphys.2022.944587] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2022] [Accepted: 09/13/2022] [Indexed: 12/03/2022] Open
Abstract
Microgravity has deleterious effects on the cardiovascular system. We evaluated some parameters of blood flow and vascular stiffness during 60 days of simulated microgravity in head-down tilt (HDT) bed rest. We also tested the hypothesis that daily exposure to 30 min of artificial gravity (1 g) would mitigate these adaptations. 24 healthy subjects (8 women) were evenly distributed in three groups: continuous artificial gravity, intermittent artificial gravity, or control. 4D flow cardiac MRI was acquired in horizontal position before (−9 days), during (5, 21, and 56 days), and after (+4 days) the HDT period. The false discovery rate was set at 0.05. The results are presented as median (first quartile; third quartile). No group or group × time differences were observed so the groups were combined. At the end of the HDT phase, we reported a decrease in the stroke volume allocated to the lower body (−30% [−35%; −22%]) and the upper body (−20% [−30%; +11%]), but in different proportions, reflected by an increased share of blood flow towards the upper body. The aortic pulse wave velocity increased (+16% [+9%; +25%]), and so did other markers of arterial stiffness (CAVI; CAVI0). In males, the time-averaged wall shear stress decreased (−13% [−17%; −5%]) and the relative residence time increased (+14% [+5%; +21%]), while these changes were not observed among females. Most of these parameters tended to or returned to baseline after 4 days of recovery. The effects of the artificial gravity countermeasure were not visible. We recommend increasing the load factor, the time of exposure, or combining it with physical exercise. The changes in blood flow confirmed the different adaptations occurring in the upper and lower body, with a larger share of blood volume dedicated to the upper body during (simulated) microgravity. The aorta appeared stiffer during the HDT phase, however all the changes remained subclinical and probably the sole consequence of reversible functional changes caused by reduced blood flow. Interestingly, some wall shear stress markers were more stable in females than in males. No permanent cardiovascular adaptations following 60 days of HDT bed rest were observed.
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Affiliation(s)
- Jeremy Rabineau
- LPHYS, Département de Cardiologie, Université Libre de Bruxelles, Brussels, Belgium
- TIPs, École Polytechnique de Bruxelles, Université Libre de Bruxelles, Brussels, Belgium
- *Correspondence: Jeremy Rabineau,
| | - Margot Issertine
- LPHYS, Département de Cardiologie, Université Libre de Bruxelles, Brussels, Belgium
| | - Fabian Hoffmann
- Institute of Aerospace Medicine, German Aerospace Center (DLR), Cologne, Germany
| | - Darius Gerlach
- Institute of Aerospace Medicine, German Aerospace Center (DLR), Cologne, Germany
| | - Enrico G. Caiani
- Electronic, Information and Biomedical Engineering Department, Politecnico di Milano, Milan, Italy
| | - Benoit Haut
- TIPs, École Polytechnique de Bruxelles, Université Libre de Bruxelles, Brussels, Belgium
| | | | - Jens Tank
- Institute of Aerospace Medicine, German Aerospace Center (DLR), Cologne, Germany
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13
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Isasi E, Isasi ME, van Loon JJWA. The application of artificial gravity in medicine and space. Front Physiol 2022; 13:952723. [PMID: 36105282 PMCID: PMC9465481 DOI: 10.3389/fphys.2022.952723] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Accepted: 07/18/2022] [Indexed: 11/13/2022] Open
Abstract
Gravity plays a crucial role in physiology. The lack of gravity, like in long duration spaceflight missions, cause pathologies in e.g., the musculoskeletal system, cardiovascular deconditioning, immune system deprivation or brain abnormalities, to just mention a few. The application of artificial gravity through short-arm human centrifugation (SAHC) has been studied as a possible countermeasure to treat spaceflight deconditioning. However, hypergravity protocols applied by using SAHC have also been used to treat different, ground-based pathologies. Such gravitational therapies have been applied in Uruguay for more than four decades now. The aim of this overview is to summarize the most important findings about the effects of gravitational therapy in different, mainly vascular based pathologies according to the experience in the Gravitational Therapy Center and to discuss the current research in the field of hypergravity applications in medicine but also as multisystem countermeasure for near weightlessness pathologies. New insight is needed on the use of hypergravity in medicine and space research and application.
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Affiliation(s)
- Eugenia Isasi
- Centro de Terapia Gravitacional, Montevideo, Uruguay
- Departamento de Histología y Embriología, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay
| | - Maria E. Isasi
- Centro de Terapia Gravitacional, Montevideo, Uruguay
- *Correspondence: Jack J. W. A. van Loon, ; Maria E. Isasi,
| | - Jack J. W. A. van Loon
- Department of Oral and Maxillofacial Surgery/Pathology, Amsterdam Movement Sciences & Amsterdam Bone Center (ABC), Amsterdam UMC location Vrije Universiteit Amsterdam & Academic Center for Dentistry Amsterdam (ACTA), Amsterdam, Netherlands
- Life Support and Physical Sciences Section (TEC-MMG), European Space Agency (ESA), European Space Research and Technology Centre (ESTEC), Noordwijk, Netherlands
- *Correspondence: Jack J. W. A. van Loon, ; Maria E. Isasi,
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14
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Mian A, Aamir Mian M. Space Medicine: Inspiring a new generation of physicians. Postgrad Med J 2022:7150864. [PMID: 37137531 DOI: 10.1136/pmj-2022-141875] [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: 04/27/2022] [Accepted: 06/18/2022] [Indexed: 11/03/2022]
Abstract
Space medicine is critical in enabling safe human exploration of space. The discipline focuses on supporting human survival, health, and performance in the austere environment of space. It is set to grow ever more important as significant transitions in the standard of space operations in the suborbital, low earth orbit (LEO) and beyond LEO domains will take place in the coming years. NASA along with their international and commercial partners have committed to returning to the Moon through the Artemis missions in this decade with the aim of achieving a permanent sustainable human presence on the lunar surface. Additionally, the development of reusable rockets is set to increase the number and frequency of humans going to space by making space travel more accessible. Commercial spaceflight and missions beyond LEO present many new challenges which space medicine physicians and researchers will need to address. Space medicine operates at the frontier of exploration, engineering, science and medicine. Aviation and Space Medicine (ASM) is the latest specialty to be recognised by the Royal College of Physicians and the General Medical Council in the UK. In this paper, we provide an introduction to space medicine, review the effects of spaceflight on human physiology and health along with countermeasures, medical and surgical issues in space, the varied roles of the ASM physician, challenges to UK space medicine practice and related research, and finally we explore the current representation of space medicine within the undergraduate curriculum.
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Affiliation(s)
- Areeb Mian
- Department of Surgery, University of Cambridge, Cambridge, UK
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15
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Mechanical deconditioning of the heart due to long-term bed rest as observed on seismocardiogram morphology. NPJ Microgravity 2022; 8:25. [PMID: 35821029 PMCID: PMC9276739 DOI: 10.1038/s41526-022-00206-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Accepted: 05/13/2022] [Indexed: 11/26/2022] Open
Abstract
During head-down tilt bed rest (HDT) the cardiovascular system is subject to headward fluid shifts. The fluid shift phenomenon is analogous to weightlessness experienced during spaceflight microgravity. The purpose of this study was to investigate the effect of prolonged 60-day bed rest on the mechanical performance of the heart using the morphology of seismocardiography (SCG). Three-lead electrocardiogram (ECG), SCG and blood pressure recordings were collected simultaneously from 20 males in a 60-day HDT study (MEDES, Toulouse, France). The study was divided into two campaigns of ten participants. The first commenced in January, and the second in September. Signals were recorded in the supine position during the baseline data collection (BDC) before bed rest, during 6° HDT bed rest and during recovery (R), post-bed rest. Using SCG and blood pressure at the finger, the following were determined: Pulse Transit Time (PTT); and left-ventricular ejection time (LVET). SCG morphology was analyzed using functional data analysis (FDA). The coefficients of the model were estimated over 20 cycles of SCG recordings of BDC12 and HDT52. SCG fiducial morphology AO (aortic valve opening) and AC (aortic valve closing) amplitudes showed significant decrease between BDC12 and HDT52 (p < 0.03). PTT and LVET were also found to decrease through HDT bed rest (p < 0.01). Furthermore, PTT and LVET magnitude of response to bed rest was found to be different between campaigns (p < 0.001) possibly due to seasonal effects on of the cardiovascular system. Correlations between FDA and cardiac timing intervals PTT and LVET using SCG suggests decreases in mechanical strength of the heart and increased arterial stiffness due to fluid shifts associated with the prolonged bed rest.
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16
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Özelbaykal B, Öğretmenoğlu G, Gedik Ş. The Effects of Space Radiation and Microgravity on Ocular Structures. Turk J Ophthalmol 2022; 52:57-63. [PMID: 35196841 PMCID: PMC8876783 DOI: 10.4274/tjo.galenos.2021.29566] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
Long-term exposure to microgravity and space radiation leads to physiological and pathological changes in human biology. Pathological neuro-ocular changes are collected under the name spaceflight-associated neuro-ocular syndrome. This review examines studies on the effects of microgravity and space radiation on the ocular structures and their results. In addition, we discuss treatment methods and hypotheses to reduce the effects of microgravity and space radiation on biological structures.
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Affiliation(s)
| | - Gökhan Öğretmenoğlu
- Adana City Training and Research Hospital, Clinic of Ophthalmology, Adana, Turkey
| | - Şansal Gedik
- Selçuk University Faculty of Medicine, Department of Ophthalmology, Konya, Turkey
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17
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Liu HY, Zhao CH, Zhang H, Wang W, Liu QJ. Simulation study on the effect of resistance exercise on the hydrodynamic microenvironment of osteocytes in microgravity. Comput Methods Biomech Biomed Engin 2022; 25:1757-1766. [PMID: 35170387 DOI: 10.1080/10255842.2022.2037130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Osteoporosis occurs in astronauts after long-term space flight owing to the lack of gravity. The mechanical microenvironment of osteocytes in load-bearing bone are changed during resistance exercise, which prevents massive bone loss in the human body. A cylindrical fluid-structure coupling finite element model for osteons with a two-stage pore structure (i.e., Haversian canal, lacunar-canalicular system) was established with the software COMSOL. In the Earth's gravity field and in microgravity, considering the effects of pulsating pressure of arterioles, a comparative study was performed on the changes in hydrodynamic microenvironment of osteocytes during human body high-intensity exercise at different frequencies (defined as causing bone to produce 3000 με) and the body is at rest. Positive and negative liquid pressure (with respect to one atmosphere pressure) alternately acted on osteocytes during human exercising, but only positive pressure acted on osteocytes during human resting. The variation range of liquid pressure acted on osteocytes during human exercising was significantly higher than that during resting. The liquid flow velocity around osteocytes during body exercise was about four orders of magnitude higher than that during resting. In microgravity, moderate physical exercise can obviously improve the hydrodynamic microenvironment of osteocytes in load-bearing bone, which could compensate for the lack of mechanical stimulation to osteocytes caused by the lack of gravity, thereby promoting the normal physiological function of osteocytes. To a certain extent, these results revealed the biomechanical mechanism by which exercise has an effect in fighting osteoporosis in astronauts.
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Affiliation(s)
- Hai-Ying Liu
- Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control, School of Mechanical Engineering, Tianjin University of Technology, Tianjin, People's Republic of China.,National Demonstration Center for Experimental Mechanical and Electrical Engineering Education (Tianjin University of Technology), Tianjin, People's Republic of China
| | - Chao-Hui Zhao
- Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control, School of Mechanical Engineering, Tianjin University of Technology, Tianjin, People's Republic of China.,National Demonstration Center for Experimental Mechanical and Electrical Engineering Education (Tianjin University of Technology), Tianjin, People's Republic of China
| | - Hao Zhang
- Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control, School of Mechanical Engineering, Tianjin University of Technology, Tianjin, People's Republic of China.,National Demonstration Center for Experimental Mechanical and Electrical Engineering Education (Tianjin University of Technology), Tianjin, People's Republic of China
| | - Wei Wang
- Department of Mechanics, School of Mechanical Engineering, Tianjin University, Tianjin, People's Republic of China
| | - Qing-Jian Liu
- Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control, School of Mechanical Engineering, Tianjin University of Technology, Tianjin, People's Republic of China.,National Demonstration Center for Experimental Mechanical and Electrical Engineering Education (Tianjin University of Technology), Tianjin, People's Republic of China
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18
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Dello Russo C, Bandiera T, Monici M, Surdo L, Yip VLM, Wotring V, Morbidelli L. Physiological adaptations affecting drug pharmacokinetics in space: what do we really know? A critical review of the literature. Br J Pharmacol 2022; 179:2538-2557. [PMID: 35170019 PMCID: PMC9314132 DOI: 10.1111/bph.15822] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 01/13/2022] [Accepted: 02/10/2022] [Indexed: 12/03/2022] Open
Abstract
As human spaceflight progresses with extended mission durations, the demand for effective and safe drugs will necessarily increase. To date, the accepted medications used during missions (for space motion sickness, sleep disturbances, allergies, pain, and sinus congestion) are administered under the assumption that they act as safely and efficaciously as on Earth. However, physiological changes have been documented in human subjects in spaceflight involving fluid shifts, muscle and bone loss, immune system dysregulation, and adjustments in the gastrointestinal tract and metabolism. These alterations may change the pharmacokinetics (PK) and pharmacodynamics of commonly used medications. Frustratingly, the information gained from bed rest studies and from in‐flight observations is incomplete and also demonstrates a high variability in drug PK. Therefore, the objectives of this review are to report (i) the impact of the space environmental stressors on human physiology in relation to PK; (ii) the state‐of‐the‐art on experimental data in space and/or in ground‐based models; (iii) the validation of ground‐based models for PK studies; and (iv) the identification of research gaps.
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Affiliation(s)
- Cinzia Dello Russo
- Università Cattolica del Sacro Cuore, Dept. of Healthcare Surveillance and Bioethics, Section of Pharmacology, Rome, Italy; Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy.,MRC Centre for Drug Safety Science and Wolfson Centre for Personalised Medicine, Institute of Systems, Molecular and Integrative Biology (ISMIB), University of Liverpool, Liverpool, UK
| | - Tiziano Bandiera
- D3-PharmaChemistry Line, Istituto Italiano di Tecnologia (IIT), Genova, Italy
| | - Monica Monici
- ASAcampus Joint Laboratory, ASA Res. Div. & Dept. of Experimental and Clinical Biomedical Sciences "Mario Serio", University of Florence, Florence, Italy
| | - Leonardo Surdo
- Space Applications Services NV/SA for the European Space Agency, NL-2200AG, Noordwijk, The Netherlands
| | - Vincent Lai Ming Yip
- MRC Centre for Drug Safety Science and Wolfson Centre for Personalised Medicine, Institute of Systems, Molecular and Integrative Biology (ISMIB), University of Liverpool, Liverpool, UK
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19
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Cardiovascular, Lymphatic, and Ocular Health in Space. Life (Basel) 2022; 12:life12020268. [PMID: 35207555 PMCID: PMC8875500 DOI: 10.3390/life12020268] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 01/22/2022] [Accepted: 02/08/2022] [Indexed: 12/01/2022] Open
Abstract
Life on Earth has evolved continuously under Earth’s 1 G force and the protection of the magnetosphere. Thus, astronauts exhibit maladaptive physiological responses during space travel. Exposure to harmful cosmic radiation and weightlessness are unique conditions to the deep-space environment responsible for several spaceflight-associated risks: visual impairment, immune dysfunction, and cancer due to cosmic radiation in astronauts. The evidence thus reviewed indicates that microgravity and cosmic radiation have deleterious effects on the cardiovascular, lymphatic, and vision systems of astronauts on long-duration space missions. The mechanisms responsible for the decline in these systems are potentially due to cytoskeletal filament rearrangement, endothelial dysfunction, and muscular atrophy. These factors may alter fluid hemodynamics within cardiovascular and lymphatic vasculatures such that greater fluid filtration causes facial and intracranial edema. Thus, microgravity induces cephalad fluid shifts contributing to spaceflight-associated neuro-ocular syndrome (SANS). Moreover, visual impairment via retinal ischemia and altered nitric oxide production may alter endothelial function. Based on rodent studies, cosmic radiation may exacerbate the effects of microgravity as observed in impaired endothelium and altered immunity. Relevant findings help understand the extent of these risks associated with spaceflight and suggest relevant countermeasures to protect astronaut health during deep-space missions.
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20
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Shankhwar V, Singh D, Deepak KK. Cardiac-vascular-respiratory coupling analysis during 6-degree head-down tilt microgravity analogue. Biomed Signal Process Control 2022. [DOI: 10.1016/j.bspc.2021.103358] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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21
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Shankhwar V, Singh D, Deepak KK. Effect of countermeasure bodygear on cardiac-vascular-respiratory coupling during 6-degree head-down tilt: An earth-based microgravity study. LIFE SCIENCES IN SPACE RESEARCH 2022; 32:45-53. [PMID: 35065760 DOI: 10.1016/j.lssr.2021.10.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2021] [Revised: 10/22/2021] [Accepted: 10/24/2021] [Indexed: 06/14/2023]
Abstract
Prolonged exposure to microgravity causes physiological deconditioning in humans. Herein, a novel designed countermeasure gravitational load modulation bodygear has been developed to deal with the ill effects of the microgravity environment. The bodygear is designed to provide the wearer an axial loading from the shoulder to the feet that simulate Earth's gravity. The present study aims to evaluate the effect of bodygear on cardiac, vascular and respiratory systems during head-down tilt (HDT) microgravity analogue. In this, 30 healthy male subjects have volunteered and their average age, height and weight were 24.56 ± 3.87 yr, 168.4 ± 9.17 cm and 65.9 ± 10.51 kg respectively. The physiological signals such as electrocardiogram (ECG), blood pressure (BP) and respiration were recorded non-invasively using Biopac MP100. The signals were sampled at 1,000 Hz and processed using MATLAB 2018b. The signals were analysed in linear well as non-linear domains. The ECG and BP were used to derive R-R interval (RRI) and systolic blood pressure (SBP). The respiration time series (RSP) was derived by extracting R-peaks from the ECG signal and using these peaks to find the respiration amplitude. The non-linear domain analysis was used for the detection and quantification of information flow among the recorded signals. Repeated measure analysis of variance with Bonferroni post-hoc paired t-test was used for statistical analysis with the p < 0.05. The experimental results show that the 6-degree HDT activates the parasympathetic system and decreased the RRI effect on SBP (p = 0.005). Interestingly with the bodygear usage, the sympathetic system activated, mean RRI decreased (p = 0.018) and blood pressure increased (p = 0.031) as compared to baseline. Further, it was also observed that the effect of RRI on SBP (p = 0.029) and SBP on RRI (p = 0.012) was increased with bodygear as compared to HDT without bodygear. The conditional entropy technique aided in analyzing the effect of bodygear on information flow variation in the cardiovascular system of the human body.
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Affiliation(s)
- Vishwajeet Shankhwar
- Department of Instrumentation and Control Engineering, Dr. B R Ambedkar National Institute of Technology, Jalandhar, Punjab-144011, India
| | - Dilbag Singh
- Department of Instrumentation and Control Engineering, Dr. B R Ambedkar National Institute of Technology, Jalandhar, Punjab-144011, India
| | - K K Deepak
- Department of Physiology, All India Institute of Medical Science, New Delhi-110029, India.
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22
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ZHANG HAO, LIU HAIYING, ZHANG CHUNQIU, LIU ZHENZHONG, WANG WEI. MULTI-SCALE MECHANICAL BEHAVIOR ANALYSIS ON FLUID–SOLID COUPLING FOR OSTEONS IN VARIOUS GRAVITATIONAL FIELDS. J MECH MED BIOL 2021. [DOI: 10.1142/s0219519421500718] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Background: Compact bone mainly consists of cylindrical osteon structures. In microgravity, the change in the mechanical microenvironment of osteocytes might be the root cause of astronauts’ bone loss during space flights. Methods: A multi-scale three-dimensional (3D) fluid–solid coupling finite element model of osteons with a two-stage pore structure was developed using COMSOL software based on the natural structure of osteocytes. Gradients in gravitational fields of [Formula: see text]1, 0, 1, 2.5, and 3.7[Formula: see text]g were used to investigate the changes in the mechanical microenvironment on osteocyte structure. The difference in arteriole pulsating pressure and static compression stress caused by each gravity gradient was investigated. Results: The mechanical response of osteocytes increased with the value of g, compared with the Earth’s gravitational field. For instance, the fluid pressure of osteocytes and the von Mises stress of bone matrix near lacunae decreased by 31.3% and 99.9%, respectively, in microgravity. Under static loading, only about 16.7% of osteocytes in microgravity and 58.3% of osteocytes in the Earth’s gravitational field could reach the fluid shear stress threshold of biological reactions in cell culture experiments. Compared with the Earth’s gravitational field, the pressure gradient inside osteocytes severely decreased in microgravity. Conclusion: The mechanical microenvironment of osteocytes in microgravity might cause significant changes in the mechanical microenvironment of osteocytes, which may lead to disuse osteoporosis in astronauts.
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Affiliation(s)
- HAO ZHANG
- Tianjin Key Laboratory for Advanced Mechatronic, System Design and Intelligent Control, School of Mechanical Engineering, Tianjin University of Technology, Tianjin 300384, P. R. China
- National Demonstration Center for Experimental, Mechanical and Electrical Engineering Education, Tianjin University of Technology, Tianjin 300384, P. R. China
| | - HAI-YING LIU
- Tianjin Key Laboratory for Advanced Mechatronic, System Design and Intelligent Control, School of Mechanical Engineering, Tianjin University of Technology, Tianjin 300384, P. R. China
- National Demonstration Center for Experimental, Mechanical and Electrical Engineering Education, Tianjin University of Technology, Tianjin 300384, P. R. China
| | - CHUN-QIU ZHANG
- Tianjin Key Laboratory for Advanced Mechatronic, System Design and Intelligent Control, School of Mechanical Engineering, Tianjin University of Technology, Tianjin 300384, P. R. China
- National Demonstration Center for Experimental, Mechanical and Electrical Engineering Education, Tianjin University of Technology, Tianjin 300384, P. R. China
| | - ZHEN-ZHONG LIU
- Tianjin Key Laboratory for Advanced Mechatronic, System Design and Intelligent Control, School of Mechanical Engineering, Tianjin University of Technology, Tianjin 300384, P. R. China
- National Demonstration Center for Experimental, Mechanical and Electrical Engineering Education, Tianjin University of Technology, Tianjin 300384, P. R. China
| | - WEI WANG
- Department of Mechanics, School of Mechanical Engineering, Tianjin University, Tianjin 300354, P. R. China
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23
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Cerri M, Hitrec T, Luppi M, Amici R. Be cool to be far: Exploiting hibernation for space exploration. Neurosci Biobehav Rev 2021; 128:218-232. [PMID: 34144115 DOI: 10.1016/j.neubiorev.2021.03.037] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Revised: 03/23/2021] [Accepted: 03/26/2021] [Indexed: 01/08/2023]
Abstract
In mammals, torpor/hibernation is a state that is characterized by an active reduction in metabolic rate followed by a progressive decrease in body temperature. Torpor was successfully mimicked in non-hibernators by inhibiting the activity of neurons within the brainstem region of the Raphe Pallidus, or by activating the adenosine A1 receptors in the brain. This state, called synthetic torpor, may be exploited for many medical applications, and for space exploration, providing many benefits for biological adaptation to the space environment, among which an enhanced protection from cosmic rays. As regards the use of synthetic torpor in space, to fully evaluate the degree of physiological advantage provided by this state, it is strongly advisable to move from Earth-based experiments to 'in the field' tests, possibly on board the International Space Station.
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Affiliation(s)
- Matteo Cerri
- Department of Biomedical and NeuroMotor Sciences, Alma Mater Studiorum -University of Bologna, Piazza di Porta S.Donato, 2 40126, Bologna, Italy.
| | - Timna Hitrec
- Department of Biomedical and NeuroMotor Sciences, Alma Mater Studiorum -University of Bologna, Piazza di Porta S.Donato, 2 40126, Bologna, Italy.
| | - Marco Luppi
- Department of Biomedical and NeuroMotor Sciences, Alma Mater Studiorum -University of Bologna, Piazza di Porta S.Donato, 2 40126, Bologna, Italy.
| | - Roberto Amici
- Department of Biomedical and NeuroMotor Sciences, Alma Mater Studiorum -University of Bologna, Piazza di Porta S.Donato, 2 40126, Bologna, Italy.
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24
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Abstract
Space travel has grown during the past 2 decades, and is expected to surge in the future with the establishment of an American Space Force, businesses specializing in commercial space travel, and National Aeronautics and Space Administration's planned sustained presence on the moon. Accompanying this rise, treating physicians are bracing for a concomitant increase in space-related medical problems, including back pain. Back pain is highly prevalent in astronauts and space travelers, with most cases being transient and self-limiting (space adaptation back pain). Pathophysiologic changes that affect the spine occur during space travel and may be attributed to microgravity, rapid acceleration and deceleration, and increased radiation. These include a loss of spinal curvature, spinal muscle atrophy, a higher rate of disc herniation, decreased proteoglycan and collagen content in intervertebral discs, and a reduction in bone density that may predispose people to vertebral endplate fractures. In this article, the authors discuss epidemiology, pathophysiology, prevention, treatment, and future research.
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25
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Kourtidou-Papadeli C, Frantzidis CA, Gilou S, Plomariti CE, Nday CM, Karnaras D, Bakas L, Bamidis PD, Vernikos J. Gravity Threshold and Dose Response Relationships: Health Benefits Using a Short Arm Human Centrifuge. Front Physiol 2021; 12:644661. [PMID: 34045973 PMCID: PMC8144521 DOI: 10.3389/fphys.2021.644661] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Accepted: 04/12/2021] [Indexed: 01/09/2023] Open
Abstract
Purpose Increasing the level of gravity passively on a centrifuge, should be equal to or even more beneficial not only to astronauts living in a microgravity environment but also to patients confined to bed. Gravity therapy (GT) may have beneficial effects on numerous conditions, such as immobility due to neuromuscular disorders, balance disorders, stroke, sports injuries. However, the appropriate configuration for administering the Gz load remains to be determined. Methods To address these issues, we studied graded G-loads from 0.5 to 2.0g in 24 young healthy, male and female participants, trained on a short arm human centrifuge (SAHC) combined with mild activity exercise within 40–59% MHR, provided by an onboard bicycle ergometer. Hemodynamic parameters, as cardiac output (CO), stroke volume (SV), mean arterial pressure (MAP), systolic blood pressure (SBP), diastolic blood pressure (DBP), and heart rate (HR) were analyzed, as well as blood gas analysis. A one-way repeated measures ANOVA and pairwise comparisons were conducted with a level of significance p < 0.05. Results Significant changes in heart rate variability (HRV) and its spectral components (Class, Fmax, and VHF) were found in all g loads when compared to standing (p < 0.001), except in 1.7 and 2.0g. There were significant changes in CO, cardiac index (CI), and cardiac power (CP) (p < 0.001), and in MAP (p = 0.003) at different artificial gravity (AG) levels. Dose-response curves were determined based on statistically significant changes in cardiovascular parameters, as well as in identifying the optimal G level for training, as well as the optimal G level for training. There were statistically significant gender differences in Cardiac Output/CO (p = 0.002) and Cardiac Power/CP (p = 0.016) during the AG training as compared to standing. More specifically, these cardiovascular parameters were significantly higher for male than female participants. Also, there was a statistically significant (p = 0.022) gender by experimental condition interaction, since the high-frequency parameter of the heart rate variability was attenuated during AG training as compared to standing but only for the female participants (p = 0.004). Conclusion The comprehensive cardiovascular evaluation of the response to a range of graded AG loads, as compared to standing, in male and female subjects provides the dose-response framework that enables us to explore and validate the usefulness of the centrifuge as a medical device. It further allows its use in precisely selecting personalized gravity therapy (GT) as needed for treatment or rehabilitation of individuals confined to bed.
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Affiliation(s)
- Chrysoula Kourtidou-Papadeli
- Biomedical Engineering & Aerospace Neuroscience, Laboratory of Medical Physics, Faculty of Health Sciences, School of Medicine, Aristotle University of Thessaloniki, Thessaloniki, Greece.,Greek Aerospace Medical Association and Space Research, Thessaloniki, Greece.,Aeromedical Center of Thessaloniki, Thessaloniki, Greece
| | - Christos A Frantzidis
- Biomedical Engineering & Aerospace Neuroscience, Laboratory of Medical Physics, Faculty of Health Sciences, School of Medicine, Aristotle University of Thessaloniki, Thessaloniki, Greece.,Greek Aerospace Medical Association and Space Research, Thessaloniki, Greece
| | - Sotiria Gilou
- Biomedical Engineering & Aerospace Neuroscience, Laboratory of Medical Physics, Faculty of Health Sciences, School of Medicine, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Christina E Plomariti
- Biomedical Engineering & Aerospace Neuroscience, Laboratory of Medical Physics, Faculty of Health Sciences, School of Medicine, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Christiane M Nday
- Biomedical Engineering & Aerospace Neuroscience, Laboratory of Medical Physics, Faculty of Health Sciences, School of Medicine, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | | | - Lefteris Bakas
- Laboratory of Aerospace and Rehabilitation Applications "Joan Vernikos" Arogi Rehabilitation Center, Thessaloniki, Greece
| | - Panagiotis D Bamidis
- Biomedical Engineering & Aerospace Neuroscience, Laboratory of Medical Physics, Faculty of Health Sciences, School of Medicine, Aristotle University of Thessaloniki, Thessaloniki, Greece.,Greek Aerospace Medical Association and Space Research, Thessaloniki, Greece
| | - Joan Vernikos
- Greek Aerospace Medical Association and Space Research, Thessaloniki, Greece.,Thirdage llc, Culpeper, VA, United States
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26
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Sater SH, Sass AM, Seiner A, Natividad GC, Shrestha D, Fu AQ, Oshinski JN, Ethier CR, Martin BA. MRI-based quantification of ophthalmic changes in healthy volunteers during acute 15° head-down tilt as an analogue to microgravity. J R Soc Interface 2021; 18:20200920. [PMID: 33906382 DOI: 10.1098/rsif.2020.0920] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Spaceflight is known to cause ophthalmic changes in a condition known as spaceflight-associated neuro-ocular syndrome (SANS). It is hypothesized that SANS is caused by cephalad fluid shifts and potentially mild elevation of intracranial pressure (ICP) in microgravity. Head-down tilt (HDT) studies are a ground-based spaceflight analogue to create cephalad fluid shifts. Here, we developed non-invasive magnetic resonance imaging (MRI)-based techniques to quantify ophthalmic structural changes under acute 15° HDT. We specifically quantified: (i) change in optic nerve sheath (ONS) and optic nerve (ON) cross-sectional area, (ii) change in ON deviation, an indicator of ON tortuosity, (iii) change in vitreous chamber depth, and (iv) an estimated ONS Young's modulus. Under acute HDT, ONS cross-sectional area increased by 4.04 mm2 (95% CI 2.88-5.21 mm2, p < 0. 000), while ON cross-sectional area remained nearly unchanged (95% CI -0.12 to 0.43 mm2, p = 0.271). ON deviation increased under HDT by 0.20 mm (95% CI 0.08-0.33 mm, p = 0.002). Vitreous chamber depth decreased under HDT by -0.11 mm (95% CI -0.21 to -0.03 mm, p = 0.009). ONS Young's modulus was estimated to be 85.0 kPa. We observed a significant effect of sex and BMI on ONS parameters, of interest since they are known risk factors for idiopathic intracranial hypertension. The tools developed herein will be useful for future analyses of ON changes in various conditions.
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Affiliation(s)
- Stuart H Sater
- Alcyone Therapeutics Inc., Lowell, MA 01852, USA.,Department of Chemical and Biological Engineering, University of Idaho, 875 Perimeter Drive, MC1122, Moscow, ID 83844-1122, USA
| | - Austin M Sass
- Department of Chemical and Biological Engineering, University of Idaho, 875 Perimeter Drive, MC1122, Moscow, ID 83844-1122, USA
| | - Akari Seiner
- Department of Chemical and Biological Engineering, University of Idaho, 875 Perimeter Drive, MC1122, Moscow, ID 83844-1122, USA
| | - Gabryel Conley Natividad
- Department of Chemical and Biological Engineering, University of Idaho, 875 Perimeter Drive, MC1122, Moscow, ID 83844-1122, USA
| | - Dev Shrestha
- Department of Chemical and Biological Engineering, University of Idaho, 875 Perimeter Drive, MC1122, Moscow, ID 83844-1122, USA
| | - Audrey Q Fu
- Department of Mathematics and Statistical Science, Institute of Bioinformatics and Evolutionary Studies, Institute for Modeling Collaboration and Innovation, University of Idaho, 875 Perimeter Drive, MC1122, Moscow, ID 83844-1122, USA
| | - John N Oshinski
- Department of Radiology and Imaging Sciences, Emory University, Atlanta, GA, USA.,Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA
| | - C Ross Ethier
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA
| | - Bryn A Martin
- Alcyone Therapeutics Inc., Lowell, MA 01852, USA.,Department of Chemical and Biological Engineering, University of Idaho, 875 Perimeter Drive, MC1122, Moscow, ID 83844-1122, USA
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27
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Zhang H, Liu HY, Zhang CQ, Liu ZZ, Wang W. Simulation of the mechanical behavior of osteons using artificial gravity devices in microgravity. Comput Methods Biomech Biomed Engin 2021; 24:1578-1587. [PMID: 33724105 DOI: 10.1080/10255842.2021.1901086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Aviation medical research shows that disuse osteoporosis will occur after long-term space flight. Even with countermeasures such as exercise and drug treatments, this outcome cannot be avoided in flight. In recent years, the application of artificial gravity devices that change the mechanical microenvironment of bone in microgravity have shown promise in mitigating the risk of disuse osteoporosis. Considering the existence of osteocytes, a fluid-solid coupling finite element model for osteons with two-stage pore structure (Haversian canal, lacunar-canalicular system) was established. In order to study the changes in the mechanical behavior of osteocytes under the action of various artificial gravity (AG) devices, including long-arm centrifuge (LAC), short-arm centrifuge (SAC), and a lower body negative pressure (LBNP) chamber. In addition, the difference in pulsating pressure and static pressure stress caused by the gravity gradient under the AG devices was examined. The simulation results showed that the AG devices could effectively improve the stress level of osteocytes in microgravity. The mechanical microenvironment of osteocytes that was provided by the LAC was closest to that of the Earth's gravitational field. The mechanical stimulation on osteocytes was not significantly improved by the SAC, but from a practical viewpoint, it occupied less space than the LAC. The LBNP chamber created a higher level of stress for osteocytes. Therefore, the LAC was an ideal device for replacing Earth's gravitational field, except for the practical limitations of its physical size. In contrast, the LBNP device had the greatest application potential in training for its expansibility and convenience.
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Affiliation(s)
- Hao Zhang
- Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control, School of Mechanical Engineering, Tianjin University of Technology, Tianjin, People's Republic of China.,National Demonstration Center for Experimental Mechanical and Electrical Engineering Education, Tianjin University of Technology, Tianjin, People's Republic of China
| | - Hai-Ying Liu
- Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control, School of Mechanical Engineering, Tianjin University of Technology, Tianjin, People's Republic of China.,National Demonstration Center for Experimental Mechanical and Electrical Engineering Education, Tianjin University of Technology, Tianjin, People's Republic of China
| | - Chun-Qiu Zhang
- Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control, School of Mechanical Engineering, Tianjin University of Technology, Tianjin, People's Republic of China.,National Demonstration Center for Experimental Mechanical and Electrical Engineering Education, Tianjin University of Technology, Tianjin, People's Republic of China
| | - Zhen-Zhong Liu
- Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control, School of Mechanical Engineering, Tianjin University of Technology, Tianjin, People's Republic of China.,National Demonstration Center for Experimental Mechanical and Electrical Engineering Education, Tianjin University of Technology, Tianjin, People's Republic of China
| | - Wei Wang
- Department of Mechanics, School of Mechanical Engineering, Tianjin University, Tianjin, People's Republic of China
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28
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Eye changes in space : New insights into clinical aspects, pathogenesis, and prevention. Ophthalmologe 2021; 118:96-101. [PMID: 33258060 DOI: 10.1007/s00347-020-01272-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
BACKGROUND More than ever research into changes in the eye caused by long-term space flight is becoming the focus of the international and national space agencies National Aeronautics and Space Administration (NASA), European Space Agency (ESA) and German Aerospace Center (DLR). In addition to space radiation-induced cataract formation considerable eye changes, summarized under space flight-associated neuro-ocular syndrome (SANS), can occur. OBJECTIVE This article gives an overview of the current state of research and future directions in the field of research concerned with ocular alterations in SANS and presents the relevance for terrestrial ophthalmological research. MATERIAL AND METHODS An analysis of existing publications on SANS in PubMed and reports on the risk of SANS published by the NASA of the USA was carried out. RESULTS The reasons for the development of the eye changes in space have not been clarified. Factors such as the increase in intracranial pressure, fluid shifts, hypercapnia and genetic factors are the subject of intensive research efforts. A terrestrial model for the induction of papilledema could be established (bed rest studies with -6° head-down tilt as a space analogue). Countermeasures for the development of eye changes, such as intermittent artificial gravity, are the subject of current research studies. CONCLUSION Research into SANS as part of bed rest studies will provide further important insights in the future for space research and also for terrestrial research. Clinical research projects can be derived from space research.
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29
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Johnson IRD, Nguyen CT, Wise P, Grimm D. Implications of Altered Endosome and Lysosome Biology in Space Environments. Int J Mol Sci 2020; 21:ijms21218205. [PMID: 33147843 PMCID: PMC7663135 DOI: 10.3390/ijms21218205] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Revised: 10/30/2020] [Accepted: 10/31/2020] [Indexed: 12/17/2022] Open
Abstract
Space exploration poses multiple challenges for mankind, not only on a technical level but also to the entire physiology of the space traveller. The human system must adapt to several environmental stressors, microgravity being one of them. Lysosomes are ubiquitous to every cell and essential for their homeostasis, playing significant roles in the regulation of autophagy, immunity, and adaptation of the organism to changes in their environment, to name a few. Dysfunction of the lysosomal system leads to age-related diseases, for example bone loss, reduced immune response or cancer. As these conditions have been shown to be accelerated following exposure to microgravity, this review elucidates the lysosomal response to real and simulated microgravity. Microgravity activates the endo-lysosomal system, with resulting impacts on bone loss, muscle atrophy and stem cell differentiation. The investigation of lysosomal adaptation to microgravity can be beneficial in the search for new biomarkers or therapeutic approaches to several disease pathologies on earth as well as the potential to mitigate pathophysiology during spaceflight.
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Affiliation(s)
- Ian R. D. Johnson
- Research in Space Environments Group, UniSA Clinical and Health Sciences, University of South Australia, Adelaide, SA 5000, Australia;
- Correspondence:
| | - Catherine T. Nguyen
- Research in Space Environments Group, UniSA Clinical and Health Sciences, University of South Australia, Adelaide, SA 5000, Australia;
| | - Petra Wise
- Department of Hematology and Oncology, Children’s Hospital of Los Angeles, Los Angeles, CA 90027, USA;
| | - Daniela Grimm
- Department of Microgravity and Translational Regenerative Medicine, Clinic for Plastic, Aesthetic and Hand Surgery, Otto-von-Guericke-University Magdeburg, 39106 Magdeburg, Germany;
- Department of Biomedicine, Aarhus University, 8000 Aarhus C, Denmark
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30
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Girardi M, Casolo A, Nuccio S, Gattoni C, Capelli C. Detraining Effects Prevention: A New Rising Challenge for Athletes. Front Physiol 2020; 11:588784. [PMID: 33178050 PMCID: PMC7593778 DOI: 10.3389/fphys.2020.588784] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Accepted: 09/04/2020] [Indexed: 12/25/2022] Open
Affiliation(s)
- Michele Girardi
- Department of Psychology, Center for Brain Science, University of Essex, Colchester, United Kingdom
| | - Andrea Casolo
- Department of Bioengineering, Imperial College London, London, United Kingdom
| | - Stefano Nuccio
- Department of Movement, Human and Health Sciences, University of Rome “Foro Italico”, Rome, Italy
| | - Chiara Gattoni
- Endurance Research Group, School Sport and Exercise Sciences, University of Kent, Chatham, United Kingdom
| | - Carlo Capelli
- Department of Neuroscience, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
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31
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Kramer A, Venegas-Carro M, Mulder E, Lee JK, Moreno-Villanueva M, Bürkle A, Gruber M. Cardiorespiratory and Neuromuscular Demand of Daily Centrifugation: Results From the 60-Day AGBRESA Bed Rest Study. Front Physiol 2020; 11:562377. [PMID: 33041861 PMCID: PMC7518067 DOI: 10.3389/fphys.2020.562377] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Accepted: 08/19/2020] [Indexed: 12/13/2022] Open
Abstract
Purpose Long stays in space require countermeasures for the degrading effects of weightlessness on the human body, and artificial gravity (AG) has been proposed as an integrated countermeasure. The aim of this study was to assess the cardiorespiratory and neuromuscular demand of AG elicited via daily centrifugation during 60 days of bed rest. Methods Twenty four participants (33 ± 9 y, 175 ± 9 cm, 74 ± 10 kg, 8 female) were subjected to 60 days of strict six-degree head-down tilt (HDT) bed rest and were randomly allocated to one of three experimental groups: 30 min of daily centrifugation with an acceleration of 1 g at the center of mass and 2 g at the feet applied continuously (cAG) or intermittently in 6 epochs of 5 min each, separated by 3 min breaks (iAG), or non-centrifuged control (CTRL). Cardiorespiratory demand during centrifugation was assessed at the beginning (HDT3) and end (HDT60) of the bed rest phase via spirometry and heart rate monitoring, leg muscle activation was monitored via electromyography. Results On average, analyses of variance revealed that heart rate during centrifugation increased by 40% (iAG) and 60% (cAG) compared to resting values (p < 0.001), while oxygen uptake did not change significantly (p = 0.96). There was a preference for calf over knee extensor muscle activation (active time soleus 57 ± 27%, gastrocnemius medialis 45 ± 27% and vastus lateralis 27 ± 27%, p < 0.001), with large inter-individual differences in leg muscle active time. AG could not prevent the increase in resting heart rate after bed rest. For most of the recorded parameters, there were little differences between cAG and iAG, with the increase in heart rate during centrifugation being a notable exception (greater increase for cAG, p = 0.01). Conclusion Daily 30 min bouts of artificial gravity elicited by centrifugation put a substantial demand on the heart as a pump without increasing oxygen consumption. If centrifugation is to be used as a countermeasure for the deteriorating effects of microgravity on physical performance, we recommend combining it with strenuous exercise.
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Affiliation(s)
- Andreas Kramer
- Department of Sport Science, University of Konstanz, Konstanz, Germany
| | | | - Edwin Mulder
- Institute of Aerospace Medicine, German Aerospace Center (DLR), Cologne, Germany
| | - Jessica K Lee
- Institute of Aerospace Medicine, German Aerospace Center (DLR), Cologne, Germany
| | | | - Alexander Bürkle
- Department of Biology, University of Konstanz, Konstanz, Germany
| | - Markus Gruber
- Department of Sport Science, University of Konstanz, Konstanz, Germany
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32
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Parganlija D, Gehlert S, Herrera F, Rittweger J, Bloch W, Zange J. Enhanced Blood Supply Through Lower Body Negative Pressure During Slow-Paced, High Load Leg Press Exercise Alters the Response of Muscle AMPK and Circulating Angiogenic Factors. Front Physiol 2020; 11:781. [PMID: 32848814 PMCID: PMC7406804 DOI: 10.3389/fphys.2020.00781] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Accepted: 06/15/2020] [Indexed: 11/30/2022] Open
Abstract
Lower body negative pressure (LBNP) is an established method of simulating the gravitational effects of orthostasis on the cardiovascular system during space flight or at supine body position on Earth. We hypothesized that LBNP added onto leg press exercise would promote leg muscle perfusion, stimulate oxygen consumption, and modify acute molecular responses. Eighteen subjects performed fifteen slow-paced concentric (4 s) and eccentric contractions (4 s) without or with 40 mmHg LBNP. Force corresponding to 6% of the one-repetition maximum (1-RM) at knee flexion gradually increased to 60% 1-RM within the first half of the range of motion, thereafter remaining constant. AMPK and P-AMPK protein expression was determined in biopsies of vastus lateralis. Venous blood samples were used to measure angiogenic factors. Physiological responses to LBNP included an elevated EMG amplitude, higher heart rate and doubling of the cardiac output compared to control (p < 0.001). Muscle total hemoglobin was increased by around 20 μmol/l vs. control (p < 0.001), accompanied by decreasing tissue oxygen saturation and elevated oxygen uptake (p < 0.05). MMP-2 levels were reduced, and the ratio of P-AMPK to AMPK elevated after exercise with LBNP (p < 0.05). MMP-9 similarly increased in both groups, whereas endostatin was only elevated in the control group (p < 0.05). Our results indicate facilitated peripheral blood supply and higher oxygen exploitation leading to activation of the energy sensor AMPK and differential regulation of angiogenic factors involved in muscle tissue remodeling and capillary growth. Simulating orthostasis with LBNP might promote beneficial structural adaptations of skeletal muscles during resistance exercise and contribute to future exercise countermeasures achieving increased muscle strength and endurance during space flight.
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Affiliation(s)
- Dajana Parganlija
- Institute of Aerospace Medicine, German Aerospace Center (DLR), Cologne, Germany.,Department of Molecular and Cellular Sports Medicine, Institute of Cardiovascular Research and Sports Medicine, German Sport University, Cologne, Germany
| | - Sebastian Gehlert
- Department of Molecular and Cellular Sports Medicine, Institute of Cardiovascular Research and Sports Medicine, German Sport University, Cologne, Germany.,Department for Biosciences of Sports, Institute of Sport Science, University of Hildesheim, Hildesheim, Germany
| | - Frankyn Herrera
- Institute of Aerospace Medicine, German Aerospace Center (DLR), Cologne, Germany
| | - Jörn Rittweger
- Institute of Aerospace Medicine, German Aerospace Center (DLR), Cologne, Germany.,Department of Pediatrics and Adolescent Medicine, University of Cologne, Cologne, Germany
| | - Wilhelm Bloch
- Department of Molecular and Cellular Sports Medicine, Institute of Cardiovascular Research and Sports Medicine, German Sport University, Cologne, Germany
| | - Jochen Zange
- Institute of Aerospace Medicine, German Aerospace Center (DLR), Cologne, Germany
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33
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Händel A, Stern C, Jordan J, Dietlein T, Enders P, Cursiefen C. [Eye changes in space : New insights into clinical aspects, pathogenesis and prevention]. Ophthalmologe 2020; 117:721-729. [PMID: 32347333 DOI: 10.1007/s00347-020-01103-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
BACKGROUND More than ever research into changes in the eye caused by long-term space flight is becoming the focus of the international and national space agencies National Aeronautics and Space Administration (NASA), European Space Agency (ESA) and German Aerospace Center (DLR). In addition to space radiation-induced cataract formation considerable eye changes, summarized under space flight-associated neuro-ocular syndrome (SANS), can occur. OBJECTIVE This article gives an overview of the current state of research and future directions in the field of research concerned with ocular alterations in SANS and presents the relevance for terrestrial ophthalmological research. MATERIAL AND METHODS An analysis of existing publications on SANS in PubMed and reports on the risk of SANS published by the NASA of the USA was carried out. RESULTS The reasons for the development of the eye changes in space have not been clarified. Factors such as the increase in intracranial pressure, fluid shifts, hypercapnia and genetic factors are the subject of intensive research efforts. A terrestrial model for the induction of papilledema could be established (bed rest studies with -6° head-down tilt as a space analogue). Countermeasures for the development of eye changes, such as intermittent artificial gravity, are the subject of current research studies. CONCLUSION Research into SANS as part of bed rest studies will provide further important insights in the future for space research and also for terrestrial research. Clinical research projects can be derived from space research.
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Affiliation(s)
- A Händel
- Zentrum für Augenheilkunde, Universitätsklinik Köln, Kerpener Str. 62, 50937, Köln, Deutschland.
| | - C Stern
- Institut für Luft- und Raumfahrtmedizin, Deutsches Zentrum für Luft- und Raumfahrt (DLR), Köln, Deutschland
| | - J Jordan
- Institut für Luft- und Raumfahrtmedizin, Deutsches Zentrum für Luft- und Raumfahrt (DLR), Köln, Deutschland.,Lehrstuhl für Luft- und Raumfahrtmedizin, Universitätsklinik Köln, Köln, Deutschland
| | - T Dietlein
- Zentrum für Augenheilkunde, Universitätsklinik Köln, Kerpener Str. 62, 50937, Köln, Deutschland
| | - P Enders
- Zentrum für Augenheilkunde, Universitätsklinik Köln, Kerpener Str. 62, 50937, Köln, Deutschland
| | - C Cursiefen
- Zentrum für Augenheilkunde, Universitätsklinik Köln, Kerpener Str. 62, 50937, Köln, Deutschland
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34
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Fagoni N, Bruseghini P, Adami A, Capelli C, Lador F, Moia C, Tam E, Bringard A, Ferretti G. Effect of Lower Body Negative Pressure on Phase I Cardiovascular Responses at Exercise Onset. Int J Sports Med 2020; 41:209-218. [PMID: 31958874 PMCID: PMC7286127 DOI: 10.1055/a-1028-7496] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
We hypothesised that vagal withdrawal and increased venous return interact in determining the
rapid cardiac output (CO) response (phase I) at exercise onset. We used lower body negative
pressure (LBNP) to increase blood distribution to the heart by muscle pump action and reduce
resting vagal activity. We expected a larger increase in stroke volume (SV) and smaller for
heart rate (HR) at progressively stronger LBNP levels, therefore CO response would remain
unchanged. To this aim ten young, healthy males performed a 50 W exercise in supine
position at 0 (Control), −15, −30 and −45 mmHg LBNP exposure.
On single beat basis, we measured HR, SV, and CO. Oxygen uptake was measured breath-by-breath.
Phase I response amplitudes were obtained applying an exponential model. LBNP increased SV
response amplitude threefold from Control to −45 mmHg. HR response amplitude
tended to decrease and prevented changes in CO response. The rapid response of CO explained
that of oxygen uptake. The rapid SV kinetics at exercise onset is compatible with an increased
venous return, whereas the vagal withdrawal conjecture cannot be dismissed for HR. The rapid CO
response may indeed be the result of two independent yet parallel mechanisms, one acting on SV,
the other on HR.
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Affiliation(s)
- Nazzareno Fagoni
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
| | - Paolo Bruseghini
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
| | - Alessandra Adami
- Department of Kinesiology, University of Rhode Island, United States
| | - Carlo Capelli
- Department of Physical Performances, Norwegian School of Sport Sciences, Oslo, Norway
| | - Frederic Lador
- Division de Pneumologie, Département des Spécialités de Médecine, Hôpitaux Universitaires de Genève, Geneva, Switzerland
| | - Christian Moia
- Département des Neurosciences Fondamentales, Université de Genève Centre Médical Universitaire, Geneve, Switzerland
| | - Enrico Tam
- Dipartimento di Scienze Neurologiche e della Visione, University of Verona, Verona, Italy
| | | | - Guido Ferretti
- Département des Neurosciences Fondamentales, Université de Genève Centre Médical Universitaire, Geneve, Switzerland
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From international ophthalmology to space ophthalmology: the threats to vision on the way to Moon and Mars colonization. Int Ophthalmol 2019; 40:775-786. [PMID: 31722052 DOI: 10.1007/s10792-019-01212-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Accepted: 10/28/2019] [Indexed: 12/29/2022]
Abstract
PURPOSE To report the ophthalmological risks of space travel. METHODS The literature about the effect of microgravity and cosmic radiation on the human eye has been reviewed, focusing on the so-called "spaceflight related neuro-ocular syndrome (SANS)", and possible remedies. RESULTS The eye is the major candidate to suffer from the adverse space conditions, so much so that SANS is the main concern of the National Aeronautics and Space Administration (NASA). SANS, that affects astronauts engaged in long-duration spaceflights, is characterized by optic nerve head swelling, flattening of the posterior region of the scleral shell, choroidal folds, retinal cotton wool spots, and hyperopic shift. Even if it seems related to an increased volume of the cerebrospinal fluid in the brain and the optic nerve sheaths, its pathogenesis is still unclear. In addition, cataract is related to the effect of galactic cosmic rays on the lens. Centrifuges, pressurizing chambers, and mechanical counter-pressure suits have been advanced to counteract the upward fluid shift responsible for the SANS syndrome. Shields with a high content of hydrogen, magnetic shielding systems, and wearable radiation shielding devices are under study to mitigate the exposure to galactic cosmic rays. CONCLUSIONS Since 1961, the year of the first manned mission outside the Earth, history has shown that the human being may venture in space. Yet, visual impairment is the top health risk for long-duration spaceflight. Effective remediation is mandatory in anticipation of long space missions and Moon and Mars colonization.
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Abstract
During spaceflight, the human cardiovascular system undergoes major changes primarily related to the effects of decreased gravitational force, or microgravity, on the human body. These changes present challenges to human adaptation and operation in space. This article reviews the knowledge gained in human experiments in the past half century of spaceflight, and summarizes our knowledge on the effects of short- and long-duration microgravity exposure on cardiovascular physiology and functioning, including fluid redistribution, autonomic reflexes, cardiac parameters, orthostatic intolerance, arrhythmias, aerobic capacity, and cardiac atrophy. This review also discusses current countermeasures for risk reduction during spaceflight, as well as future directions in cardiovascular research in space.
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Diaz-Artiles A, Navarro Tichell P, Perez F. Cardiopulmonary Responses to Sub-Maximal Ergometer Exercise in a Hypo-Gravity Analog Using Head-Down Tilt and Head-Up Tilt. Front Physiol 2019; 10:720. [PMID: 31263424 PMCID: PMC6590066 DOI: 10.3389/fphys.2019.00720] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2019] [Accepted: 05/23/2019] [Indexed: 12/12/2022] Open
Abstract
After more than 50 years of spaceflight, we still do not know what is the appropriate range of gravity levels that are required to maintain normal physiological function in humans. This research effort aimed to investigate musculoskeletal, cardiovascular, and pulmonary responses between 0 and 1 g. A human experiment was conducted to investigate acute physiological outcomes to simulated altered-gravity with and without ergometer exercise using a head-down tilt (HDT)/head-up tilt (HUT) paradigm. A custom tilting platform was built to simulate multiple gravitational loads in the head-to-toe direction (Gz) by tilting the bed to the appropriate angle. Gravity levels included: Microgravity (-6°HDT), Moon (0.17g-Gz at +9.5°HUT), Mars (0.38g-Gz at +22.3°HUT), and Earth (1g-Gz at +90° upright). Fourteen healthy subjects performed an exercise protocol at each simulated gravity level that consisted of three work rates (50W, 75W, 100W) while maintaining a constant cycling rate of 90 rpm. Multiple cardiopulmonary variables were gathered, including volume of oxygen uptake (VO2), volume of carbon dioxide output (VCO2), pulmonary ventilation (VE), tidal volume (VT), respiratory rate (Rf), blood pressure, and heart rate (HR) using a portable metabolic system and a brachial blood pressure cuff. Foot forces were also measured continuously during the protocol. Exercise data were analyzed with repeated-measures ANOVA with Bonferroni correction for multiple comparisons, and regression models were fitted to the experimental data to generate dose-response curves as a function of simulated AG-levels and exercise intensity. Posture showed a main effect in all variables except for systolic blood pressure. In particular, VO2, VCO2, VE, VT, Rf, and HR showed average changes across exercise conditions between Microgravity and 1 g (i.e., per unit of simulated AG) of -97.88 mL/min/g, -95.10 mL/min/g, -3.95 L/min/g, 0.165 L/g, -5.33 breaths/min/g, and 5.05 bpm/g, respectively. In the case of VO2, further pairwise comparisons did not show significant differences between conditions, which was consistent with previous studies using supine and HDT postures. For all variables (except HR), comparisons between Mars and Earth conditions were not statistically different, suggesting that ergometer exercise at a gravitational stress comparable to Mars gravity (∼3/8 g) could provide similar physiological stimuli as cycling under 1 g on Earth.
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Affiliation(s)
- Ana Diaz-Artiles
- Department of Aerospace Engineering, Texas A&M University, College Station, TX, United States
| | - Patricia Navarro Tichell
- Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, NY, United States
| | - Francisca Perez
- Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, NY, United States
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Dillon EL, Sheffield-Moore M, Durham WJ, Ploutz-Snyder LL, Ryder JW, Danesi CP, Randolph KM, Gilkison CR, Urban RJ. Efficacy of Testosterone plus NASA Exercise Countermeasures during Head-Down Bed Rest. Med Sci Sports Exerc 2019; 50:1929-1939. [PMID: 29924745 DOI: 10.1249/mss.0000000000001616] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
INTRODUCTION Prolonged confinement to head-down bed rest (HDBR) results in musculoskeletal losses similar to those observed during long-duration space flight. Exercise countermeasures by themselves have not completely prevented the deleterious losses in muscle mass or function in HDBR or space flight. PURPOSE The objective was to investigate the safety and efficacy of intermittent, low-dose testosterone treatment in conjunction with NASA exercise (SPRINT) countermeasures during 70 d of 6° HDBR. METHODS Healthy men (35 ± 8 yr) were randomized into one of three groups that remained inactive (CON) or performed exercise 6 d·wk in addition to receiving either placebo (PEX) or testosterone treatment (TEX, 100 mg·wk). Testosterone/placebo injections were administered once a week for 2 wk, followed by 2 wk off and so on, during HDBR. RESULTS Total, leg, and trunk lean body mass (LBM) consistently decreased in CON, increased in TEX, and had little or no changes in PEX. Total, leg, and trunk fat mass consistently increased in CON and PEX and decreased in TEX. Leg strength decreased in CON, whereas PEX and TEX were protected against loss in strength. Changes in leg LBM correlated positively with changes in leg muscle strength. CONCLUSIONS Addition of a testosterone countermeasure enhanced the preventative actions of exercise against body composition changes during long-term HDBR in healthy eugonadal men. This is the first report to demonstrate that cycled, low-dose testosterone treatment increases LBM under conditions of strict exercise control. These results are clinically relevant to the development of safe and effective therapies against muscle atrophy during long-term bed rest, aging, and disease where loss of muscle mass and strength is a risk. The potential space flight applications of such countermeasure combinations deserve further investigations.
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Affiliation(s)
- E Lichar Dillon
- Department of Internal Medicine, University of Texas Medical Branch, Galveston, TX
| | | | - William J Durham
- Department of Internal Medicine, University of Texas Medical Branch, Galveston, TX
| | | | | | - Christopher P Danesi
- Department of Internal Medicine, University of Texas Medical Branch, Galveston, TX
| | - Kathleen M Randolph
- Department of Internal Medicine, University of Texas Medical Branch, Galveston, TX
| | - Charles R Gilkison
- Department of Internal Medicine, University of Texas Medical Branch, Galveston, TX
| | - Randall J Urban
- Department of Internal Medicine, University of Texas Medical Branch, Galveston, TX
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Zou Y, Qin T, Wang N, Li J, Xu M. Passive force control of multimodal astronaut training robot. INT J ADV ROBOT SYST 2019. [DOI: 10.1177/1729881419848261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
For the purpose of solving the problem of astronaut training in weightlessness environment, this article proposes a multimodal astronaut training robot to enable astronauts to perform running, bench press and deep squat training in the weightless environment, so as to help them mitigate the adverse effects brought by the space adaptation syndrome. Taking the modularized wire driving unit as the research object, the dynamic model of the passive force servo system was established; and the passive force control strategy was designed. The experimental results show that the system is of good stability, high steady-state accuracy, and excellent dynamic quality after correction. When the given signal frequency is 10 Hz, the system phase lag is about 9°, and the loading error is about 5%. The passive force servo control strategy can effectively reduce the surplus force. When the speed disturbance frequency of carrying unit is within 3 Hz, the elimination rate of the surplus force can reach 90%.
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Affiliation(s)
- Yupeng Zou
- College of Mechanical and Electronic Engineering, China University of Petroleum, Qingdao, China
| | - Tao Qin
- School of Mechanical Engineering, Hubei University of Arts and Science, Xiangyang, China
| | - Nuo Wang
- College of Mechanical and Electronic Engineering, China University of Petroleum, Qingdao, China
| | - Junqing Li
- College of Mechanical and Electronic Engineering, China University of Petroleum, Qingdao, China
| | - Ming Xu
- College of Mechanical and Electronic Engineering, China University of Petroleum, Qingdao, China
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40
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Parganlija D, Nieberg V, Sauer M, Rittweger J, Bloch W, Zange J. Lower body negative pressure enhances oxygen availability in the knee extensor muscles during intense resistive exercise in supine position. Eur J Appl Physiol 2019; 119:1289-1303. [PMID: 30915538 PMCID: PMC6517352 DOI: 10.1007/s00421-019-04113-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Accepted: 02/26/2019] [Indexed: 12/12/2022]
Abstract
Purpose During exercise in supine posture or under microgravity in space, the gravity-dependent component of local blood pressure in leg muscles at upright posture can be simulated by lower body negative pressure (LBNP). We hypothesized that during resistive exercise LBNP favors oxygen availability in lower extremities, benefiting energy levels and performance of working muscles. Methods In permutated crossover design, nine subjects performed a series of fifteen slow-paced concentric (4 s) and eccentric contractions (4 s) without or with 40 mmHg LBNP and 4 s pause between repetitions. The force at knee flexion was 6% of the one repetition maximum (1-RM) and gradually increased to 60% 1RM in the first half of the individual range of motion, subsequently remaining constant until full extension. Results During the low force periods of continuous exercise, LBNP enhanced the refill of capillary blood measured by near infrared spectroscopy, amplifying the increase of total haemoglobin by about 20 µmol/l (p < 0.01) and oxyhaemoglobin by about 10 µmol/l (p < 0.01). During continuous exercise, LBNP induced a trend towards a lower EMG increment. This LBNP effect was not found when the periods of low forces at knee flexion were extended by 4 s pauses. Increased respiratory oxygen uptake (+ 0.1 l/min, p < 0.05) indicated overall enhanced muscle energy turn-over. Conclusions Our results suggest stimulation of oxidative metabolism through LBNP enables working muscles to meet the energy demands of intense exercise. Further research is needed on the consequences for energy metabolism and the molecular control of growth and differentiation.
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Affiliation(s)
- Dajana Parganlija
- Space Physiology Department, Institute of Aerospace Medicine, German Aerospace Center (DLR), Cologne, Germany. .,Institute of Cardiovascular Research and Sports Medicine, German Sport University, Cologne, Germany. .,IQWiG, Institute for Quality and Efficiency in Health Care, Im Mediapark 8, 50670, Cologne, Germany.
| | - Vita Nieberg
- Space Physiology Department, Institute of Aerospace Medicine, German Aerospace Center (DLR), Cologne, Germany.,Department of Sport and Health Sciences, Technical University of Munich, Munich, Germany
| | - Marc Sauer
- Space Physiology Department, Institute of Aerospace Medicine, German Aerospace Center (DLR), Cologne, Germany.,Institute of Training Science and Sport Informatics, German Sport University Cologne, Cologne, Germany
| | - Jörn Rittweger
- Space Physiology Department, Institute of Aerospace Medicine, German Aerospace Center (DLR), Cologne, Germany.,Department of Pediatrics and Adolescent Medicine, University of Cologne, Cologne, Germany
| | - Wilhelm Bloch
- Institute of Cardiovascular Research and Sports Medicine, German Sport University, Cologne, Germany
| | - Jochen Zange
- Space Physiology Department, Institute of Aerospace Medicine, German Aerospace Center (DLR), Cologne, Germany
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Alessandro C, Sarabadani Tafreshi A, Riener R. Cardiovascular responses to leg muscle loading during head-down tilt at rest and after dynamic exercises. Sci Rep 2019; 9:2804. [PMID: 30808948 PMCID: PMC6391465 DOI: 10.1038/s41598-019-39360-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Accepted: 01/18/2019] [Indexed: 01/09/2023] Open
Abstract
The physiological processes underlying hemodynamic homeostasis can be modulated by muscle activity and gravitational loading. The effects of leg muscle activity on cardiovascular regulation have been observed during orthostatic stress. Here, we evaluated such effects during head-down tilt (HDT). In this posture, the gravitational gradient along the body is different than in upright position, leading to increased central blood volume and reduced venous pooling. We compared the cardiovascular signals obtained with and without leg muscle loading during HDT in healthy human subjects, both at rest and during recovery from leg-press exercises using a robotic device. Further, we compared such cardiovascular responses to those obtained during upright position. Loading leg muscles during HDT at rest led to significantly higher values of arterial blood pressure than without muscle loading, and restored systolic values to those observed during upright posture. Maintaining muscle loading post-exercise altered the short-term cardiovascular responses, but not the values of the signals five minutes after the exercise. These results suggest that leg muscle activity modulates cardiovascular regulation during HDT. This modulation should therefore be considered when interpreting cardiovascular responses to conditions that affect both gravity loading and muscle activity, for example bed rest or microgravity.
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Affiliation(s)
- Cristiano Alessandro
- Northwestern University, Feinberg School of Medicine, Department of Physiology, Chicago, USA.
- ETH Zurich, Sensory-Motor Systems Lab, Institute of Robotics and Intelligent Systems, Department of Health Sciences and Technology, Zurich, Switzerland.
| | - Amirehsan Sarabadani Tafreshi
- ETH Zurich, Sensory-Motor Systems Lab, Institute of Robotics and Intelligent Systems, Department of Health Sciences and Technology, Zurich, Switzerland
| | - Robert Riener
- ETH Zurich, Sensory-Motor Systems Lab, Institute of Robotics and Intelligent Systems, Department of Health Sciences and Technology, Zurich, Switzerland
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Maggioni MA, Castiglioni P, Merati G, Brauns K, Gunga HC, Mendt S, Opatz OS, Rundfeldt LC, Steinach M, Werner A, Stahn AC. High-Intensity Exercise Mitigates Cardiovascular Deconditioning During Long-Duration Bed Rest. Front Physiol 2018; 9:1553. [PMID: 30510516 PMCID: PMC6252355 DOI: 10.3389/fphys.2018.01553] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2018] [Accepted: 10/16/2018] [Indexed: 02/02/2023] Open
Abstract
Head-down-tilt bed rest (HDT) mimics the changes in hemodynamics and autonomic cardiovascular control induced by weightlessness. However, the time course and reciprocal interplay of these adaptations, and the effective exercise protocol as a countermeasure need further clarification. The overarching aim of this work (as part of a European Space Agency sponsored long-term bed rest study) was therefore to evaluate the time course of cardiovascular hemodynamics and autonomic control during prolonged HDT and to assess whether high-intensity, short-duration exercise could mitigate these effects. A total of n = 23 healthy, young, male participants were randomly allocated to two groups: training (TRAIN, n = 12) and non-training (CTRL, n = 11) before undergoing a 60-day HDT. The TRAIN group underwent a resistance training protocol using reactive jumps (5–6 times per week), whereas the CTRL group did not perform countermeasures. Finger blood pressure (BP), heart rate (HR), and stroke volume were collected beat-by-beat for 10 min in both sitting and supine positions 7 days before HDT (BDC−7) and 10 days after HDT (R+10), as well as on the 2nd (HDT2), 28th (HDT28), and 56th (HDT56) day of HDT. We investigated (1) the isolated effects of long-term HDT by comparing all the supine positions (including BDC−7 and R+10 at 0 degrees), and (2) the reactivity of the autonomic response before and after long-term HDT using a specific postural stimulus (i.e., supine vs. sitting). Two-factorial linear mixed models were used to assess the time course of HDT and the effect of the countermeasure. Starting from HDT28 onwards, HR increased (p < 0.02) and parasympathetic tone decreased exclusively in the CTRL group (p < 0.0001). Moreover, after 60-day HDT, CTRL participants showed significant impairments in increasing cardiac sympathovagal balance and controlling BP levels during postural shift (supine to sitting), whereas TRAIN participants did not. Results show that a 10-day recovery did not compensate for the cardiovascular and autonomic deconditioning following 60-day HDT. This has to be considered when designing rehabilitation programs—not only for astronauts but also in general public healthcare. High-intensity, short-duration exercise training effectively minimized these impairments and should therefore deserve consideration as a cardiovascular deconditioning countermeasure for spaceflight.
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Affiliation(s)
- Martina A Maggioni
- Charité-Universitätsmedizin Berlin, Institute of Physiology, Center for Space Medicine and Extreme Environments Berlin, Berlin, Germany.,Department of Biomedical Sciences for Health, Università degli Studi di Milano, Milan, Italy
| | | | - Giampiero Merati
- Department of Biomedical Sciences for Health, Università degli Studi di Milano, Milan, Italy.,IRCCS Fondazione Don Carlo Gnocchi, Milan, Italy
| | - Katharina Brauns
- Charité-Universitätsmedizin Berlin, Institute of Physiology, Center for Space Medicine and Extreme Environments Berlin, Berlin, Germany
| | - Hanns-Christian Gunga
- Charité-Universitätsmedizin Berlin, Institute of Physiology, Center for Space Medicine and Extreme Environments Berlin, Berlin, Germany
| | - Stefan Mendt
- Charité-Universitätsmedizin Berlin, Institute of Physiology, Center for Space Medicine and Extreme Environments Berlin, Berlin, Germany
| | - Oliver S Opatz
- Charité-Universitätsmedizin Berlin, Institute of Physiology, Center for Space Medicine and Extreme Environments Berlin, Berlin, Germany
| | - Lea C Rundfeldt
- Charité-Universitätsmedizin Berlin, Institute of Physiology, Center for Space Medicine and Extreme Environments Berlin, Berlin, Germany
| | - Mathias Steinach
- Charité-Universitätsmedizin Berlin, Institute of Physiology, Center for Space Medicine and Extreme Environments Berlin, Berlin, Germany
| | - Anika Werner
- Charité-Universitätsmedizin Berlin, Institute of Physiology, Center for Space Medicine and Extreme Environments Berlin, Berlin, Germany.,Université de Normandie, INSERM U 1075 COMETE, Caen, France
| | - Alexander C Stahn
- Charité-Universitätsmedizin Berlin, Institute of Physiology, Center for Space Medicine and Extreme Environments Berlin, Berlin, Germany.,Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
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43
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Strollo F, Gentile S, Strollo G, Mambro A, Vernikos J. Recent Progress in Space Physiology and Aging. Front Physiol 2018; 9:1551. [PMID: 30483144 PMCID: PMC6240610 DOI: 10.3389/fphys.2018.01551] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Accepted: 10/16/2018] [Indexed: 12/17/2022] Open
Abstract
Astronauts coming back from long-term space missions present with different health problems potentially affecting mission performance, involving all functional systems and organs and closely resembling those found in the elderly. This review points out the most recent advances in the literature in areas of expertise in which specific research groups were particularly creative, and as they relate to aging and to possible benefits on Earth for disabled people. The update of new findings and approaches in space research refers especially to neuro-immuno-endocrine-metabolic interactions, optic nerve edema, motion sickness and muscle-tendon-bone interplay and aims at providing the curious - and even possibly naïve young researchers – with a source of inspiration and of creative ideas for translational research.
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Affiliation(s)
| | - Sandro Gentile
- Campania University "Luigi Vanvitelli" and Nefrocenter Research Network, Naples, Italy
| | | | - Andrea Mambro
- Anesthesiology and Resuscitation Unit, "Misercordia" Hospital, Grosseto, Italy
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44
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Li WY, Li XY, Tian YH, Chen XR, Zhou J, Zhu BY, Xi HR, Gao YH, Xian CJ, Chen KM. Pulsed electromagnetic fields prevented the decrease of bone formation in hindlimb-suspended rats by activating sAC/cAMP/PKA/CREB signaling pathway. Bioelectromagnetics 2018; 39:569-584. [PMID: 30350869 DOI: 10.1002/bem.22150] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2018] [Accepted: 09/30/2018] [Indexed: 12/21/2022]
Abstract
Microgravity is one of the main threats to the health of astronauts. Pulsed electromagnetic fields (PEMFs) have been considered as one of the potential countermeasures for bone loss induced by space flight. However, the optimal therapeutic parameters of PEMFs have not been obtained and the action mechanism is still largely unknown. In this study, a set of optimal therapeutic parameters for PEMFs (50 Hz, 0.6 mT 50% duty cycle and 90 min/day) selected based on high-throughput screening with cultured osteoblasts was used to prevent bone loss in rats induced by hindlimb suspension, a commonly accepted animal model to simulate the space environment. It was found that hindlimb suspension for 4 weeks led to significant decreases in femoral and vertebral bone mineral density (BMD) and their maximal loads, severe deterioration in bone micro-structure, and decreases in levels of bone formation markers and increases in bone resorption markers. PEMF treatment prevented about 50% of the decreased BMD and maximal loads, preserved the microstructure of cancellous bone and thickness of cortical bone, and inhibited decreases in bone formation markers. Histological analyses revealed that PEMFs significantly alleviated the reduction in osteoblast number and inhibited the increase in adipocyte number in the bone marrow. PEMFs also blocked decreases in serum levels of parathyroid hormone and its downstream signal molecule cAMP, and maintained the phosphorylation levels of protein kinase A (PKA) and cAMP response element-binding protein (CREB). The expression level of soluble adenylyl cyclases (sAC) was also maintained. It therefore can be concluded that PEMFs partially prevented the bone loss induced by weightless environment by maintaining bone formation through signaling of the sAC/cAMP/PKA/CREB pathway. Bioelectromagnetics. 39:569-584, 2018. © 2018 Wiley Periodicals, Inc.
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Affiliation(s)
- Wen-Yuan Li
- School of Life Science and Engineering, Lanzhou University of Technology, Lanzhou, China.,Institute of Orthopaedics, Lanzhou General Hospital of CPLA, Lanzhou, China
| | - Xue-Yan Li
- School of Life Science and Engineering, Lanzhou University of Technology, Lanzhou, China
| | - Yong-Hui Tian
- School of Life Science and Engineering, Lanzhou University of Technology, Lanzhou, China
| | - Xin-Ru Chen
- College of Life Sciences, Northwest A & F University, Yanglin, China
| | - Jian Zhou
- Institute of Orthopaedics, Lanzhou General Hospital of CPLA, Lanzhou, China
| | - Bao-Ying Zhu
- Institute of Orthopaedics, Lanzhou General Hospital of CPLA, Lanzhou, China
| | - Hui-Rong Xi
- Institute of Orthopaedics, Lanzhou General Hospital of CPLA, Lanzhou, China
| | - Yu-Hai Gao
- Institute of Orthopaedics, Lanzhou General Hospital of CPLA, Lanzhou, China
| | - Cory J Xian
- Sansom Institute for Health Research, School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, Australia
| | - Ke-Ming Chen
- Institute of Orthopaedics, Lanzhou General Hospital of CPLA, Lanzhou, China
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Daunis M, Bayers T, Bai L, Vargas L, Symons T, Caruso J. The effect of familiarization on squats done with a robotic exoskeleton. ISOKINET EXERC SCI 2018. [DOI: 10.3233/ies-184129] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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46
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Trudel G, Uhthoff HK, Laneuville O. Hemolysis during and after 21 days of head-down-tilt bed rest. Physiol Rep 2018; 5:5/24/e13469. [PMID: 29263114 PMCID: PMC5742697 DOI: 10.14814/phy2.13469] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Revised: 09/12/2017] [Accepted: 09/14/2017] [Indexed: 12/22/2022] Open
Abstract
Hemoconcentration is observed in bed rest studies, descent from altitude, and exposure to microgravity. Hemoconcentration triggers erythrocyte losses to subsequently normalize erythrocyte concentration. The mechanisms of erythrocyte loss may involve enhanced hemolysis, but has never been measured directly in bed rest studies. Steady‐state hemolysis was evaluated by measuring two heme degradation products, endogenous carbon monoxide concentration [CO] and urobilinogen in feces, in 10 healthy men, before, during, and after two campaigns of 21 days of 6° head‐down‐tilt (HDT) bed rest. The subjects were hemoconcentrated at 10 and 21 days of bed rest: mean concentrations of hemoglobin (15.0 ± 0.2 g/L and 14.6 ± 0.1 g/L, respectively) and erythrocytes (5.18 ± 0.06E6/μL and 5.02 ± 0.06E6/μL, respectively) were increased compared to baseline (all Ps < 0.05). In contrast, mean hemoglobin mass (743 ± 19 g) and number of erythrocytes (2.56 ± 0.07E13) were decreased at 21 days of bed rest (both Ps < 0.05). Indicators of hemolysis mean [CO] (1660 ± 49 ppb and 1624 ± 48 ppb, respectively) and fecal urobilinogen concentration (180 ± 23 mg/day and 199 ± 22 mg/day, respectively) were unchanged at 10 and 21 days of bed rest compared to baseline (both Ps > 0.05). A significant decrease in [CO] (−505 ppb) was measured at day 28 after bed rest. HDT bed rest caused hemoconcentration in parallel with lower hemoglobin mass. Circulating indicators of hemolysis remained unchanged throughout bed rest supporting that enhanced hemolysis did not contribute significantly to erythrocyte loss during the hemoconcentration of bed rest. At day 28 after bed rest, decreased hemolysis accompanied the recovery of erythrocytes, a novel finding.
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Affiliation(s)
- Guy Trudel
- The Ottawa Hospital Rehabilitation Centre, Ottawa, Ontario, Canada .,University of Ottawa, Faculty of Medicine, Department of Medicine, Ottawa, Ontario, Canada.,Ottawa Hospital Research Institute, Clinical Epidemiology Program, Ottawa, Ontario, Canada
| | - Hans K Uhthoff
- Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada
| | - Odette Laneuville
- Department of Biology, Faculty of Science, University of Ottawa, Ottawa, Ontario, Canada
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47
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Evans JM, Knapp CF, Goswami N. Artificial Gravity as a Countermeasure to the Cardiovascular Deconditioning of Spaceflight: Gender Perspectives. Front Physiol 2018; 9:716. [PMID: 30034341 PMCID: PMC6043777 DOI: 10.3389/fphys.2018.00716] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Accepted: 05/24/2018] [Indexed: 12/11/2022] Open
Abstract
Space flight-induced physiological deconditioning resulting from decreased gravitational input, decreased plasma volume, and disruption of regulatory mechanisms is a significant problem in returning astronauts as well as in normal aging. Here we review effects of a promising countermeasure on cardiovascular systems of healthy men and women undergoing Earth-based models of space-flight. This countermeasure is produced by a centrifuge and called artificial gravity (AG). Numerous studies have determined that AG improves orthostatic tolerance (as assessed by various protocols) of healthy ambulatory men, of men deconditioned by bed rest or by immersion (both wet and dry) and, in one case, following spaceflight. Although a few studies of healthy, ambulatory women and one study of women deconditioned by furosemide, have reported improvement of orthostatic tolerance following exposure to AG, studies of bed-rested women exposed to AG have not been conducted. However, in ambulatory, normovolemic subjects, AG training was more effective in men than women and more effective in subjects who exercised during AG than in those who passively rode the centrifuge. Acute exposure to an AG protocol, individualized to provide a common stimulus to each person, also improved orthostatic tolerance of normovolemic men and women and of furosemide-deconditioned men and women. Again, men's tolerance was more improved than women's. In both men and women, exposure to AG increased stroke volume, so greater improvement in men vs. women was due in part to their different vascular responses to AG. Following AG exposure, resting blood pressure (via decreased vascular resistance) decreased in men but not women, indicating an increase in men's vascular reserve. Finally, in addition to counteracting space flight deconditioning, improved orthostatic tolerance through AG-induced improvement of stroke volume could benefit aging men and women on Earth.
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Affiliation(s)
- Joyce M. Evans
- Department of Biomedical Engineering, University of Kentucky, Lexington, KY, United States
| | - Charles F. Knapp
- Department of Biomedical Engineering, University of Kentucky, Lexington, KY, United States
| | - Nandu Goswami
- Physiology, Otto Loewi Research Center for Vascular Biology, Immunology and Inflammation, Medical University of Graz, Graz, Austria
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48
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Verma AK, Xu D, Bruner M, Garg A, Goswami N, Blaber AP, Tavakolian K. Comparison of Autonomic Control of Blood Pressure During Standing and Artificial Gravity Induced via Short-Arm Human Centrifuge. Front Physiol 2018; 9:712. [PMID: 29988521 PMCID: PMC6026653 DOI: 10.3389/fphys.2018.00712] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2018] [Accepted: 05/23/2018] [Indexed: 12/11/2022] Open
Abstract
Autonomic control of blood pressure is essential toward maintenance of cerebral perfusion during standing, failure of which could lead to fainting. Long-term exposure to microgravity deteriorates autonomic control of blood pressure. Consequently, astronauts experience orthostatic intolerance on their return to gravitational environment. Ground-based studies suggest sporadic training in artificial hypergravity can mitigate spaceflight deconditioning. In this regard, short-arm human centrifuge (SAHC), capable of creating artificial hypergravity of different g-loads, provides an auspicious training tool. Here, we compare autonomic control of blood pressure during centrifugation creating 1-g and 2-g at feet with standing in natural gravity. Continuous blood pressure was acquired simultaneously from 13 healthy participants during supine baseline, standing, supine recovery, centrifugation of 1-g, and 2-g, from which heart rate (RR) and systolic blood pressure (SBP) were derived. The autonomic blood pressure regulation was assessed via spectral analysis of RR and SBP, spontaneous baroreflex sensitivity, and non-linear heart rate and blood pressure causality (RR↔SBP). While majority of these blood pressure regulatory indices were significantly different (p < 0.05) during standing and 2-g centrifugation compared to baseline, no change (p > 0.05) was observed in the same indices during 2-g centrifugation compared to standing. The findings of the study highlight the capability of artificial gravity (2-g at feet) created via SAHC toward evoking blood pressure regulatory controls analogous to standing, therefore, a potential utility toward mitigating deleterious effects of microgravity on cardiovascular performance and minimizing post-flight orthostatic intolerance in astronauts.
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Affiliation(s)
- Ajay K. Verma
- Department of Electrical Engineering, University of North Dakota, Grand Forks, ND, United States
| | - Da Xu
- Department of Biomedical Physiology and Kinesiology, Simon Fraser University, Burnaby, BC, Canada
| | - Michelle Bruner
- Department of Biomedical Physiology and Kinesiology, Simon Fraser University, Burnaby, BC, Canada
| | - Amanmeet Garg
- Department of Engineering Science, Simon Fraser University, Burnaby, BC, Canada
| | - Nandu Goswami
- Physiology Division, Otto Loewi Research Center for Vascular Biology, Immunology and Inflammation, Medical University of Graz, Graz, Austria
| | - Andrew P. Blaber
- Department of Electrical Engineering, University of North Dakota, Grand Forks, ND, United States
- Department of Biomedical Physiology and Kinesiology, Simon Fraser University, Burnaby, BC, Canada
| | - Kouhyar Tavakolian
- Department of Electrical Engineering, University of North Dakota, Grand Forks, ND, United States
- Department of Biomedical Physiology and Kinesiology, Simon Fraser University, Burnaby, BC, Canada
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49
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Jiang M, Lyu Q, Bai YG, Liu H, Yang J, Cheng JH, Zheng M, Ma J. Focal adhesions are involved in simulated-microgravity-induced basilar and femoral arterial remodelling in rats. Can J Physiol Pharmacol 2018. [PMID: 29527943 DOI: 10.1139/cjpp-2017-0665] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Recent studies have suggested that microgravity-induced arterial remodelling contributes to post-flight orthostatic intolerance and that multiple mechanisms are involved in arterial remodelling. However, the initial mechanism by which haemodynamic changes induce arterial remodelling is unknown. Focal adhesions (FAs) are dynamic protein complexes that have mechanotransduction properties. This study aimed to investigate the role of FAs in simulated-microgravity-induced basilar and femoral arterial remodelling. A 4-week hindlimb-unweighted (HU) rat model was used to simulate the effects of microgravity, and daily 1-hour intermittent artificial gravity (IAG) was used to prevent arterial remodelling. After 4-week HU, wall thickness, volume of smooth muscle cells (SMCs) and collagen content were increased in basilar artery but decreased in femoral artery (P < 0.05). Additionally, the expression of p-FAK Y397 and p-Src Y418 was increased and reduced in SMCs of basilar and femoral arteries, respectively, by HU (P < 0.05). The number of FAs was increased in basilar artery and reduced in femoral artery by HU (P < 0.05). Furthermore, daily 1-hour IAG prevented HU-induced differential structural adaptations and changes in FAs of basilar and femoral arteries. These results suggest that FAs may act as mechanosensors in arterial remodelling by initiating intracellular signal transduction in response to altered mechanical stress induced by microgravity.
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Affiliation(s)
- Min Jiang
- Department of Aerospace Physiology, Key Laboratory of Aerospace Medicine of Ministry of Education, Fourth Military Medical University, Xi'an 710032, Shaanxi Province, China.,Department of Aerospace Physiology, Key Laboratory of Aerospace Medicine of Ministry of Education, Fourth Military Medical University, Xi'an 710032, Shaanxi Province, China
| | - Qiang Lyu
- Department of Aerospace Physiology, Key Laboratory of Aerospace Medicine of Ministry of Education, Fourth Military Medical University, Xi'an 710032, Shaanxi Province, China.,Department of Aerospace Physiology, Key Laboratory of Aerospace Medicine of Ministry of Education, Fourth Military Medical University, Xi'an 710032, Shaanxi Province, China
| | - Yun-Gang Bai
- Department of Aerospace Physiology, Key Laboratory of Aerospace Medicine of Ministry of Education, Fourth Military Medical University, Xi'an 710032, Shaanxi Province, China.,Department of Aerospace Physiology, Key Laboratory of Aerospace Medicine of Ministry of Education, Fourth Military Medical University, Xi'an 710032, Shaanxi Province, China
| | - Huan Liu
- Department of Aerospace Physiology, Key Laboratory of Aerospace Medicine of Ministry of Education, Fourth Military Medical University, Xi'an 710032, Shaanxi Province, China.,Department of Aerospace Physiology, Key Laboratory of Aerospace Medicine of Ministry of Education, Fourth Military Medical University, Xi'an 710032, Shaanxi Province, China
| | - Jing Yang
- Department of Aerospace Physiology, Key Laboratory of Aerospace Medicine of Ministry of Education, Fourth Military Medical University, Xi'an 710032, Shaanxi Province, China.,Department of Aerospace Physiology, Key Laboratory of Aerospace Medicine of Ministry of Education, Fourth Military Medical University, Xi'an 710032, Shaanxi Province, China
| | - Jiu-Hua Cheng
- Department of Aerospace Physiology, Key Laboratory of Aerospace Medicine of Ministry of Education, Fourth Military Medical University, Xi'an 710032, Shaanxi Province, China.,Department of Aerospace Physiology, Key Laboratory of Aerospace Medicine of Ministry of Education, Fourth Military Medical University, Xi'an 710032, Shaanxi Province, China
| | - Ming Zheng
- Department of Aerospace Physiology, Key Laboratory of Aerospace Medicine of Ministry of Education, Fourth Military Medical University, Xi'an 710032, Shaanxi Province, China.,Department of Aerospace Physiology, Key Laboratory of Aerospace Medicine of Ministry of Education, Fourth Military Medical University, Xi'an 710032, Shaanxi Province, China
| | - Jin Ma
- Department of Aerospace Physiology, Key Laboratory of Aerospace Medicine of Ministry of Education, Fourth Military Medical University, Xi'an 710032, Shaanxi Province, China.,Department of Aerospace Physiology, Key Laboratory of Aerospace Medicine of Ministry of Education, Fourth Military Medical University, Xi'an 710032, Shaanxi Province, China
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50
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Zhang LF, Hargens AR. Spaceflight-Induced Intracranial Hypertension and Visual Impairment: Pathophysiology and Countermeasures. Physiol Rev 2017; 98:59-87. [PMID: 29167331 DOI: 10.1152/physrev.00017.2016] [Citation(s) in RCA: 129] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Revised: 05/25/2017] [Accepted: 05/26/2017] [Indexed: 12/21/2022] Open
Abstract
Visual impairment intracranial pressure (VIIP) syndrome is considered an unexplained major risk for future long-duration spaceflight. NASA recently redefined this syndrome as Spaceflight-Associated Neuro-ocular Syndrome (SANS). Evidence thus reviewed supports that chronic, mildly elevated intracranial pressure (ICP) in space (as opposed to more variable ICP with posture and activity on Earth) is largely accounted for by loss of hydrostatic pressures and altered hemodynamics in the intracranial circulation and the cerebrospinal fluid system. In space, an elevated pressure gradient across the lamina cribrosa, caused by a chronic but mildly elevated ICP, likely elicits adaptations of multiple structures and fluid systems in the eye which manifest themselves as the VIIP syndrome. A chronic mismatch between ICP and intraocular pressure (IOP) in space may acclimate the optic nerve head, lamina cribrosa, and optic nerve subarachnoid space to a condition that is maladaptive to Earth, all contributing to the pathogenesis of space VIIP syndrome. Relevant findings help to evaluate whether artificial gravity is an appropriate countermeasure to prevent this seemingly adverse effect of long-duration spaceflight.
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Affiliation(s)
- Li-Fan Zhang
- Department of Aerospace Physiology, Fourth Military Medical University, Xi'an, China; and Department of Orthopaedic Surgery, University of California, San Diego, California
| | - Alan R Hargens
- Department of Aerospace Physiology, Fourth Military Medical University, Xi'an, China; and Department of Orthopaedic Surgery, University of California, San Diego, California
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