1
|
Etlin S, Rose J, Bielski L, Walter C, Kleinman AS, Mason CE. The human microbiome in space: parallels between Earth-based dysbiosis, implications for long-duration spaceflight, and possible mitigation strategies. Clin Microbiol Rev 2024; 37:e0016322. [PMID: 39136453 PMCID: PMC11391694 DOI: 10.1128/cmr.00163-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/13/2024] Open
Abstract
SUMMARYThe human microbiota encompasses the diverse communities of microorganisms that reside in, on, and around various parts of the human body, such as the skin, nasal passages, and gastrointestinal tract. Although research is ongoing, it is well established that the microbiota exert a substantial influence on the body through the production and modification of metabolites and small molecules. Disruptions in the composition of the microbiota-dysbiosis-have also been linked to various negative health outcomes. As humans embark upon longer-duration space missions, it is important to understand how the conditions of space travel impact the microbiota and, consequently, astronaut health. This article will first characterize the main taxa of the human gut microbiota and their associated metabolites, before discussing potential dysbiosis and negative health consequences. It will also detail the microbial changes observed in astronauts during spaceflight, focusing on gut microbiota composition and pathogenic virulence and survival. Analysis will then turn to how astronaut health may be protected from adverse microbial changes via diet, exercise, and antibiotics before concluding with a discussion of the microbiota of spacecraft and microbial culturing methods in space. The implications of this review are critical, particularly with NASA's ongoing implementation of the Moon to Mars Architecture, which will include weeks or months of living in space and new habitats.
Collapse
Affiliation(s)
- Sofia Etlin
- Department of Physiology and Biophysics, Weill Cornell Medicine, New York, New York, USA
- Department of Biology, Cornell University, Ithaca, New York, USA
- BioAstra Inc., New York, New York, USA
| | - Julianna Rose
- Department of Physiology and Biophysics, Weill Cornell Medicine, New York, New York, USA
- Department of Biology, Cornell University, Ithaca, New York, USA
- BioAstra Inc., New York, New York, USA
| | - Luca Bielski
- Department of Physiology and Biophysics, Weill Cornell Medicine, New York, New York, USA
- Department of Biology, Cornell University, Ithaca, New York, USA
| | - Claire Walter
- Department of Physiology and Biophysics, Weill Cornell Medicine, New York, New York, USA
- Department of Biology, Cornell University, Ithaca, New York, USA
- BioAstra Inc., New York, New York, USA
| | - Ashley S Kleinman
- Department of Physiology and Biophysics, Weill Cornell Medicine, New York, New York, USA
- The HRH Prince Alwaleed Bin Talal Bin Abdulaziz Alsaud Institute for Computational Biomedicine, Weill Cornell Medicine, New York, New York, USA
| | - Christopher E Mason
- Department of Physiology and Biophysics, Weill Cornell Medicine, New York, New York, USA
- BioAstra Inc., New York, New York, USA
- The HRH Prince Alwaleed Bin Talal Bin Abdulaziz Alsaud Institute for Computational Biomedicine, Weill Cornell Medicine, New York, New York, USA
- The Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, New York, USA
- Tri-Institutional Biology and Medicine program, Weill Cornell Medicine, New York, New York, USA
- WorldQuant Initiative for Quantitative Prediction, Weill Cornell Medicine, New York, New York, USA
| |
Collapse
|
2
|
Casula M, Fais G, Manis C, Scano P, Verseux C, Concas A, Cao G, Caboni P. Cultivation and nutritional characteristics of Chlorella vulgaris cultivated using Martian regolith and synthetic urine. LIFE SCIENCES IN SPACE RESEARCH 2024; 42:108-116. [PMID: 39067982 DOI: 10.1016/j.lssr.2024.06.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2024] [Revised: 06/18/2024] [Accepted: 06/21/2024] [Indexed: 07/30/2024]
Abstract
Long-term spatial missions will require sustainable methods for biomass production using locally available resources. This study investigates the feasibility of cultivating Chlorella vulgaris, a high value microalgal specie, using a leachate of Martian regolith and synthetic human urine as nutrient sources. The microalga was grown in a standard medium (BBM) mixed with 0, 20, 40, 60, or 100 % Martian medium (MM). MM did not significantly affect final biomass concentrations. Total carbohydrate and protein contents decreased with increasing MM fractions between 0 % and 60 %, but biomass in the 100% MM showed the highest levels of carbohydrates and proteins (25.2 ± 0.9 % and 37.1 ± 1.4 % of the dry weight, respectively, against 19.0 ± 1.7 % and 32.0 ± 2.7 % in the absence of MM). In all MM-containing media, the fraction of the biomass represented by total lipids was lower (by 3.2 to 4.5%) when compared to BBM. Conversely, total carotenoids increased, with the highest value (97.3 ± 1.5 mg/100 g) measured with 20% MM. In a three-dimensional principal component analysis of triacylglycerols, samples clustered according to growth media; a strong impact of growth media on triacylglycerol profiles was observed. Overall, our findings suggest that microalgal biomass produced using regolith and urine can be used as a valuable component of astronauts' diet during missions to Mars.
Collapse
Affiliation(s)
- Mattia Casula
- Interdepartmental Center of Environmental Science and Engineering (CINSA), University of Cagliari, Via San Giorgio 12, 09124 Cagliari, Italy
| | - Giacomo Fais
- Interdepartmental Center of Environmental Science and Engineering (CINSA), University of Cagliari, Via San Giorgio 12, 09124 Cagliari, Italy; Department of Mechanical, Chemical and Materials Engineering, University of Cagliari, Piazza d'Armi, 09123 Cagliari, Italy
| | - Cristina Manis
- Department of Life and Environmental Sciences, University of Cagliari, Cittadella Universitaria, Blocco A, SP8 Km 0.700, 09042 Monserrato, Italy
| | - Paola Scano
- Department of Life and Environmental Sciences, University of Cagliari, Cittadella Universitaria, Blocco A, SP8 Km 0.700, 09042 Monserrato, Italy
| | - Cyprien Verseux
- Center of Applied Space Technology and Microgravity (ZARM), University of Bremen, Am Fallturm 2, 28359 Bremen, Germany
| | - Alessandro Concas
- Interdepartmental Center of Environmental Science and Engineering (CINSA), University of Cagliari, Via San Giorgio 12, 09124 Cagliari, Italy; Department of Mechanical, Chemical and Materials Engineering, University of Cagliari, Piazza d'Armi, 09123 Cagliari, Italy
| | - Giacomo Cao
- Interdepartmental Center of Environmental Science and Engineering (CINSA), University of Cagliari, Via San Giorgio 12, 09124 Cagliari, Italy; Department of Mechanical, Chemical and Materials Engineering, University of Cagliari, Piazza d'Armi, 09123 Cagliari, Italy
| | - Pierluigi Caboni
- Department of Life and Environmental Sciences, University of Cagliari, Cittadella Universitaria, Blocco A, SP8 Km 0.700, 09042 Monserrato, Italy.
| |
Collapse
|
3
|
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.
Collapse
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.
| |
Collapse
|
4
|
Gonzalez Viejo C, Harris N, Fuentes S. Assessment of changes in sensory perception, biometrics and emotional response for spaceexploration by simulating microgravity positions. Food Res Int 2024; 175:113827. [PMID: 38129014 DOI: 10.1016/j.foodres.2023.113827] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2023] [Revised: 11/28/2023] [Accepted: 12/02/2023] [Indexed: 12/23/2023]
Abstract
Long-term space exploration endeavors, encompassing journeys from the Earth to the Moon by 2030 and subsequent voyages from the Moon to Mars by 2040, necessitate the utilization of plant-based materials not solely for sustenance and refreshments but also the production of pharmaceuticals and repair compounds, such as plastics, among others. Nevertheless, the vital aspects of research in this domain pertain to the nutritional value and sensory perception associated with plant-based food. Prior investigations have shown altered sensory perception in space, manifested as diminished olfactory sensations and heightened taste perception (saltiness and sweetness). Nonetheless, studies concerning changes in aroma, basic tastes, and mouthfeel have been limited due to the logistical challenges associated with conducting experiments in the unique environment of space. To address this limitation, the present study employed sensory trials and biometrics from video using simulated microgravity chairs to simulate alterations in sensory perception akin to those encountered in space conditions. The findings of this study align with previous reports of changes in aroma and taste perception and contribute to the understanding of changes in the mouthfeel, heart rate, blood pressure, and emotional response that could be experienced in space environments. These experimental endeavors are critical to facilitate the advancement and development of novel plants and food materials tailored to the requirements of long-term space exploration.
Collapse
Affiliation(s)
- Claudia Gonzalez Viejo
- Digital Agriculture, Food and Wine Research Group, Faculty of Science, The University of Melbourne, VIC 3010, Australia; ARC Centre of Excellence for Plants in Space, The University of Melbourne, Australia
| | - Natalie Harris
- Digital Agriculture, Food and Wine Research Group, Faculty of Science, The University of Melbourne, VIC 3010, Australia
| | - Sigfredo Fuentes
- Digital Agriculture, Food and Wine Research Group, Faculty of Science, The University of Melbourne, VIC 3010, Australia; ARC Centre of Excellence for Plants in Space, The University of Melbourne, Australia; Tecnologico de Monterrey, School of Engineering and Science, Ave. Eugenio Garza Sada 2501, Monterrey, N.L. 64849, Mexico.
| |
Collapse
|
5
|
Izzo LG, El Nakhel C, Rouphael Y, Proietti S, Paglialunga G, Moscatello S, Battistelli A, Iovane M, Romano LE, De Pascale S, Aronne G. Applying productivity and phytonutrient profile criteria in modelling species selection of microgreens as Space crops for astronaut consumption. FRONTIERS IN PLANT SCIENCE 2023; 14:1210566. [PMID: 37636122 PMCID: PMC10450622 DOI: 10.3389/fpls.2023.1210566] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/22/2023] [Accepted: 07/06/2023] [Indexed: 08/29/2023]
Abstract
Introduction Long-duration missions in outer Space will require technologies to regenerate environmental resources such as air and water and to produce food while recycling consumables and waste. Plants are considered the most promising biological regenerators to accomplish these functions, due to their complementary relationship with humans. Plant cultivation for Space starts with small plant growth units to produce fresh food to supplement stowed food for astronauts' onboard spacecrafts and orbital platforms. The choice of crops must be based on limiting factors such as time, energy, and volume. Consequently, small, fast-growing crops are needed to grow in microgravity and to provide astronauts with fresh food rich in functional compounds. Microgreens are functional food crops recently valued for their color and flavor enhancing properties, their rich phytonutrient content and short production cycle. Candidate species of microgreens to be harvested and eaten fresh by crew members, belong to the families Brassicaceae, Asteraceae, Chenopodiaceae, Lamiaceae, Apiaceae, Amarillydaceae, Amaranthaceae, and Cucurbitaceae. Methods In this study we developed and applied an algorithm to objectively compare numerous genotypes of microgreens intending to select those with the best productivity and phytonutrient profile for cultivation in Space. The selection process consisted of two subsequent phases. The first selection was based on literature data including 39 genotypes and 25 parameters related to growth, phytonutrients (e.g., tocopherol, phylloquinone, ascorbic acid, polyphenols, lutein, carotenoids, violaxanthin), and mineral elements. Parameters were implemented in a mathematical model with prioritization criteria to generate a ranking list of microgreens. The second phase was based on germination and cultivation tests specifically designed for this study and performed on the six top species resulting from the first ranking list. For the second selection, experimental data on phytonutrients were expressed as metabolite production per day per square meter. Results and discussion In the final ranking list radish and savoy cabbage resulted with the highest scores based on their productivity and phytonutrient profile. Overall, the algorithm with prioritization criteria allowed us to objectively compare candidate species and obtain a ranking list based on the combination of numerous parameters measured in the different species. This method can be also adapted to new species, parameters, or re-prioritizing the parameters for specific selection purposes.
Collapse
Affiliation(s)
- Luigi Gennaro Izzo
- Department of Agricultural Sciences, University of Naples Federico II, Portici, Italy
| | - Christophe El Nakhel
- Department of Agricultural Sciences, University of Naples Federico II, Portici, Italy
| | - Youssef Rouphael
- Department of Agricultural Sciences, University of Naples Federico II, Portici, Italy
| | - Simona Proietti
- National Research Council of Italy, Research Institute on Terrestrial Ecosystems, Porano, Italy
| | - Gabriele Paglialunga
- National Research Council of Italy, Research Institute on Terrestrial Ecosystems, Porano, Italy
| | - Stefano Moscatello
- National Research Council of Italy, Research Institute on Terrestrial Ecosystems, Porano, Italy
| | - Alberto Battistelli
- National Research Council of Italy, Research Institute on Terrestrial Ecosystems, Porano, Italy
| | - Maurizio Iovane
- Department of Agricultural Sciences, University of Naples Federico II, Portici, Italy
| | - Leone Ermes Romano
- Department of Agricultural Sciences, University of Naples Federico II, Portici, Italy
| | - Stefania De Pascale
- Department of Agricultural Sciences, University of Naples Federico II, Portici, Italy
| | - Giovanna Aronne
- Department of Agricultural Sciences, University of Naples Federico II, Portici, Italy
| |
Collapse
|
6
|
Ross C, Sablani S, Tang J. Preserving Ready-to-Eat Meals Using Microwave Technologies for Future Space Programs. Foods 2023; 12:foods12061322. [PMID: 36981248 PMCID: PMC10048495 DOI: 10.3390/foods12061322] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2023] [Revised: 02/20/2023] [Accepted: 03/16/2023] [Indexed: 03/22/2023] Open
Abstract
The crewed suborbital and space flights launched by private companies over the past three years have rejuvenated public interest in space travel, including space tourism. Ready-to-eat meals (MREs) are the main source of nutrients and energy for space travelers. It is critical that those meals are free of bacterial and viral pathogens and have adequate shelf life. The participation of private companies in space programs will create new opportunities and demand for high-quality and microbiologically safe MREs for future space travels. In this article, we provide a brief review of nutrition and energy requirements for human activities in space. We discuss the general thermal processing requirements for control of bacterial and viral pathogens in MREs and introduce advanced thermal preservation technologies based on microwaves for production of MREs with different shelf-lives under various storage conditions. We also present the latest advancements in the development of polymer packaging materials for quality preservation of thermally stabilized MREs over extended storage. Finally, we recommend future research on issues related to the sensory quality of specially formulated MREs, microbial safety of dried foods that complement high moisture MREs, and food package waste management in future space missions.
Collapse
Affiliation(s)
- Carolyn Ross
- School of Food Science, Washington State University, Pullman, WA 99164, USA
| | - Shyam Sablani
- Department of Biological Systems Engineering, Washington State University, Pullman, WA 99164, USA
| | - Juming Tang
- Department of Biological Systems Engineering, Washington State University, Pullman, WA 99164, USA
- Correspondence:
| |
Collapse
|
7
|
Pramanik J, Kumar A, Panchal L, Prajapati B. Countermeasures for Maintaining Cardiovascular Health in Space Missions. Curr Cardiol Rev 2023; 19:57-67. [PMID: 37005513 PMCID: PMC10518885 DOI: 10.2174/1573403x19666230330083225] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 01/21/2023] [Accepted: 02/06/2023] [Indexed: 04/04/2023] Open
Abstract
During space exploration, the human body is subjected to altered atmospheric environments and gravity, exposure to radiation, sleep disturbance, and mental pressures; all these factors are responsible for cardiovascular diseases. Under microgravity, the physiological changes related to cardiovascular diseases are the cephalic fluid shift, dramatic reduction in central venous pressure, changes in blood rheology and endothelial function, cerebrovascular abnormalities, headaches, optic disc edema, intracranial hypertension, congestion of the jugular vein, facial swelling, and loss of taste. Generally, five countermeasures are used to maintain cardiovascular health (during and after space missions), including shielding, nutritional, medicinal, exercise, and artificial gravity. This article concludes with how to reduce space missions' impact on cardiovascular health with the help of various countermeasures.
Collapse
Affiliation(s)
- Jhilam Pramanik
- Department of Food Technology, ITM University, Gwalior, Madhya Pradesh, India
| | - Akash Kumar
- Department of Food Technology, SRM University, Sonipat, Haryana, India
| | - Lakshay Panchal
- Maharishi Markandeshwar Institute of Physiotherapy and Rehabilitation, Maharishi Markandeshwar University, Mullana, Haryana, India
| | - Bhupendra Prajapati
- Shree S.K. Patel College of Pharmaceutical Education and Research, Ganpat University, India
| |
Collapse
|
8
|
Bone metabolism during strict head-down tilt bed rest and exposure to elevated levels of ambient CO 2. NPJ Microgravity 2022; 8:57. [PMID: 36526672 PMCID: PMC9758179 DOI: 10.1038/s41526-022-00245-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Accepted: 11/03/2022] [Indexed: 12/23/2022] Open
Abstract
Astronauts on the International Space Station are exposed to levels of atmospheric carbon dioxide (CO2) above typical terrestrial levels. We explored the possibility that increased levels of ambient CO2 further stimulate bone resorption during bed rest. We report here data from 2 ground-based spaceflight analog studies in which 12 male and 7 female subjects were placed in a strict 6° head-down tilt (HDT) position for either 30 days at 0.5% ambient CO2 or 60 days with nominal environmental exposure to CO2. Bone mineral density (BMD) and bone mineral content (BMC) were determined using dual-energy X-ray absorptiometry (DXA). Blood and urine were collected before and after HDT for biochemical analysis. No change was detected in either BMD or BMC, as expected given the study duration. Bone resorption markers increased after bed rest as expected; however, elevated CO2 had no additive effect. Elevated CO2 did not affect concentrations of minerals in serum and urine. Serum parathyroid hormone and 1,25-dihydroxyvitamin D were both reduced after bed rest, likely secondary to calcium efflux from bone. In summary, exposure to 0.5% CO2 for 30 days did not exacerbate the typical bone resorption response observed after HDT bed rest. Furthermore, results from these strict HDT studies were similar to data from previous bed rest studies, confirming that strict 30-60 days of HDT can be used to evaluate changes in bone metabolism. This is valuable in the continuing effort to develop and refine efficacious countermeasure protocols to mitigate bone loss during spaceflight in low-Earth orbit and beyond.
Collapse
|
9
|
Seoane-Viaño I, Ong JJ, Basit AW, Goyanes A. To infinity and beyond: Strategies for fabricating medicines in outer space. Int J Pharm X 2022; 4:100121. [PMID: 35782363 PMCID: PMC9240807 DOI: 10.1016/j.ijpx.2022.100121] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Revised: 06/08/2022] [Accepted: 06/09/2022] [Indexed: 02/06/2023] Open
Abstract
Recent advancements in next generation spacecrafts have reignited public excitement over life beyond Earth. However, to safeguard the health and safety of humans in the hostile environment of space, innovation in pharmaceutical manufacturing and drug delivery deserves urgent attention. In this review/commentary, the current state of medicines provision in space is explored, accompanied by a forward look on the future of pharmaceutical manufacturing in outer space. The hazards associated with spaceflight, and their corresponding medical problems, are first briefly discussed. Subsequently, the infeasibility of present-day medicines provision systems for supporting deep space exploration is examined. The existing knowledge gaps on the altered clinical effects of medicines in space are evaluated, and suggestions are provided on how clinical trials in space might be conducted. An envisioned model of on-site production and delivery of medicines in space is proposed, referencing emerging technologies (e.g. Chemputing, synthetic biology, and 3D printing) being developed on Earth that may be adapted for extra-terrestrial use. This review concludes with a critical analysis on the regulatory considerations necessary to facilitate the adoption of these technologies and proposes a framework by which these may be enforced. In doing so, this commentary aims to instigate discussions on the pharmaceutical needs of deep space exploration, and strategies on how these may be met. Space is a hostile environment that threatens human health and drug stability. Data on the behaviour of medicines in space is critical but lacking. Novel drug manufacturing and delivery strategies are needed to safeguard crewmembers’ safety. Chemputing, synthetic biology, and 3D printing are examples of such emerging technologies. A regulatory framework for space medicines must be implemented to assure quality.
Collapse
Affiliation(s)
- Iria Seoane-Viaño
- Department of Pharmaceutics, UCL School of Pharmacy, University College London, 29-39 Brunswick Square, London WC1N 1AX, UK
- Department of Pharmacology, Pharmacy and Pharmaceutical Technology, Paraquasil Group (GI-2109), Faculty of Pharmacy, Health Research Institute of Santiago de Compostela (IDIS), University of Santiago de Compostela (USC), Santiago de Compostela 15782, Spain
| | - Jun Jie Ong
- Department of Pharmaceutics, UCL School of Pharmacy, University College London, 29-39 Brunswick Square, London WC1N 1AX, UK
| | - Abdul W. Basit
- Department of Pharmaceutics, UCL School of Pharmacy, University College London, 29-39 Brunswick Square, London WC1N 1AX, UK
- FabRx Ltd., 3 Romney Road, Ashford, Kent TN24 0RW, UK
- Corresponding authors at: Department of Pharmaceutics, UCL School of Pharmacy, University College London, 29-39 Brunswick Square, London WC1N 1AX, UK.
| | - Alvaro Goyanes
- Department of Pharmaceutics, UCL School of Pharmacy, University College London, 29-39 Brunswick Square, London WC1N 1AX, UK
- FabRx Ltd., 3 Romney Road, Ashford, Kent TN24 0RW, UK
- Departamento de Farmacología, Farmacia y Tecnología Farmacéutica, I+D Farma Group (GI-1645), Facultad de Farmacia, The Institute of Materials (iMATUS) and Health Research Institute of Santiago de Compostela (IDIS), Universidade de Santiago de Compostela (USC), Santiago de Compostela, 15782, Spain
- Corresponding authors at: Department of Pharmaceutics, UCL School of Pharmacy, University College London, 29-39 Brunswick Square, London WC1N 1AX, UK.
| |
Collapse
|
10
|
Thamer S, Buckey JC. First Void Urinary Calcium for Tracking Bone Loss and Kidney Stone Risk in Space. Aerosp Med Hum Perform 2022; 93:546-550. [DOI: 10.3357/amhp.5979.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
INTRODUCTION: Microgravity exposure unloads the skeleton. This increases urinary calcium excretion, which reflects both increased bone loss and kidney stone formation risk. We studied the probability that first morning void (FMV) urinary calcium (Uca) measurements would capture
the highest Uca concentration in a day.METHODS: For 8 wk, three men and three women collected void-by-void 24-h urine samples weekly. Uca concentration was analyzed using a calcein-based system. Uca concentrations were ranked among all samples from each person. FMV and non-FMV (nFMV)
Uca concentrations were compared with a Mann Whitney U-test. The probability that an FMV would capture the highest Uca concentration in a day was assessed.RESULTS: Among 377 voids collected, 46 were FMV and 331 were nFMV. Among all samples, the Uca concentration for FMV was
significantly higher than nFMV (P < 0.0001). Out of the 46 FMVs, 24 were highest in Uca concentration for the corresponding 24-h period, giving a 52.2% probability that any given FMV would capture the highest Uca concentration in a day. The probability of measuring the highest Uca
concentration from at least 1 d increased to 77.1%, and 89.1% when two or three FMVs were collected respectively.DISCUSSION: Acquiring 2–3 repeated FMVs provides a high likelihood of capturing the highest Uca from a day. This suggests repeated first morning void Uca concentrations
could assess the risk of bone loss and kidney stone formation, which may provide ability for real-time implementation of countermeasure programs to prevent bone and renal complications in prolonged spaceflight.Thamer S, Buckey JC. First void urinary calcium for tracking bone loss
and kidney stone risk in space. Aerosp Med Hum Perform. 2022; 93(7):546–550.
Collapse
|
11
|
Dissociation of Bone Resorption and Formation in Spaceflight and Simulated Microgravity: Potential Role of Myokines and Osteokines? Biomedicines 2022; 10:biomedicines10020342. [PMID: 35203551 PMCID: PMC8961781 DOI: 10.3390/biomedicines10020342] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 01/27/2022] [Accepted: 01/28/2022] [Indexed: 11/16/2022] Open
Abstract
The dissociation of bone formation and resorption is an important physiological process during spaceflight. It also occurs during local skeletal unloading or immobilization, such as in people with neuromuscular disorders or those who are on bed rest. Under these conditions, the physiological systems of the human body are perturbed down to the cellular level. Through the absence of mechanical stimuli, the musculoskeletal system and, predominantly, the postural skeletal muscles are largely affected. Despite in-flight exercise countermeasures, muscle wasting and bone loss occur, which are associated with spaceflight duration. Nevertheless, countermeasures can be effective, especially by preventing muscle wasting to rescue both postural and dynamic as well as muscle performance. Thus far, it is largely unknown how changes in bone microarchitecture evolve over the long term in the absence of a gravity vector and whether bone loss incurred in space or following the return to the Earth fully recovers or partly persists. In this review, we highlight the different mechanisms and factors that regulate the humoral crosstalk between the muscle and the bone. Further we focus on the interplay between currently known myokines and osteokines and their mutual regulation.
Collapse
|
12
|
Pavez Loriè E, Baatout S, Choukér A, Buchheim JI, Baselet B, Dello Russo C, Wotring V, Monici M, Morbidelli L, Gagliardi D, Stingl JC, Surdo L, Yip VLM. The Future of Personalized Medicine in Space: From Observations to Countermeasures. Front Bioeng Biotechnol 2021; 9:739747. [PMID: 34966726 PMCID: PMC8710508 DOI: 10.3389/fbioe.2021.739747] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2021] [Accepted: 11/19/2021] [Indexed: 12/12/2022] Open
Abstract
The aim of personalized medicine is to detach from a “one-size fits all approach” and improve patient health by individualization to achieve the best outcomes in disease prevention, diagnosis and treatment. Technological advances in sequencing, improved knowledge of omics, integration with bioinformatics and new in vitro testing formats, have enabled personalized medicine to become a reality. Individual variation in response to environmental factors can affect susceptibility to disease and response to treatments. Space travel exposes humans to environmental stressors that lead to physiological adaptations, from altered cell behavior to abnormal tissue responses, including immune system impairment. In the context of human space flight research, human health studies have shown a significant inter-individual variability in response to space analogue conditions. A substantial degree of variability has been noticed in response to medications (from both an efficacy and toxicity perspective) as well as in susceptibility to damage from radiation exposure and in physiological changes such as loss of bone mineral density and muscle mass in response to deconditioning. At present, personalized medicine for astronauts is limited. With the advent of longer duration missions beyond low Earth orbit, it is imperative that space agencies adopt a personalized strategy for each astronaut, starting from pre-emptive personalized pre-clinical approaches through to individualized countermeasures to minimize harmful physiological changes and find targeted treatment for disease. Advances in space medicine can also be translated to terrestrial applications, and vice versa. This review places the astronaut at the center of personalized medicine, will appraise existing evidence and future preclinical tools as well as clinical, ethical and legal considerations for future space travel.
Collapse
Affiliation(s)
| | - Sarah Baatout
- Radiobiology Unit, Belgian Nuclear Research Centre (SCK CEN), Mol, Belgium.,Department of Biotechnology, Ghent University, Ghent, Belgium
| | - Alexander Choukér
- Laboratory of Translational Research "Stress and Immunity", Department of Anesthesiology, Hospital of the Ludwig-Maximilians-University, Munich, Germany
| | - Judith-Irina Buchheim
- Laboratory of Translational Research "Stress and Immunity", Department of Anesthesiology, Hospital of the Ludwig-Maximilians-University, Munich, Germany
| | - Bjorn Baselet
- Radiobiology Unit, Belgian Nuclear Research Centre (SCK CEN), Mol, Belgium
| | - Cinzia Dello Russo
- Department of Healthcare Surveillance and Bioethics, Section of Pharmacology, Università Cattolica Del Sacro Cuore, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy.,MRC Centre for Drug Safety Science and Wolfson Centre for Personalized Medicine, Institute of Systems, Molecular and Integrative Biology (ISMIB), University of Liverpool, Liverpool, United Kingdom
| | | | - Monica Monici
- ASA Campus Joint Laboratory, ASA Research Division, Department of Experimental and Clinical Biomedical Sciences, University of Florence, Florence, Italy
| | | | - Dimitri Gagliardi
- Manchester Institute of Innovation Research, Alliance Manchester Business School, The University of Manchester, Manchester, United Kingdom
| | - Julia Caroline Stingl
- Institute of Clinical Pharmacology, University Hospital of the RWTH Aachen, Aachen, Germany
| | - Leonardo Surdo
- Space Applications Services NV/SA for the European Space Agency, Noordwijk, Netherlands
| | - Vincent Lai Ming Yip
- MRC Centre for Drug Safety Science and Wolfson Centre for Personalized Medicine, Institute of Systems, Molecular and Integrative Biology (ISMIB), University of Liverpool, Liverpool, United Kingdom
| |
Collapse
|
13
|
Tang H, Rising HH, Majji M, Brown RD. Long-Term Space Nutrition: A Scoping Review. Nutrients 2021; 14:nu14010194. [PMID: 35011072 PMCID: PMC8747021 DOI: 10.3390/nu14010194] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Revised: 12/23/2021] [Accepted: 12/28/2021] [Indexed: 01/30/2023] Open
Abstract
This scoping review aimed to identify current evidence and gaps in the field of long-term space nutrition. Specifically, the review targeted critical nutritional needs during long-term manned missions in outer space in addition to the essential components of a sustainable space nutrition system for meeting these needs. The search phrase "space food and the survival of astronauts in long-term missions" was used to collect the initial 5432 articles from seven Chinese and seven English databases. From these articles, two independent reviewers screened titles and abstracts to identify 218 articles for full-text reviews based on three themes and 18 keyword combinations as eligibility criteria. The results suggest that it is possible to address short-term adverse environmental factors and nutritional deficiencies by adopting effective dietary measures, selecting the right types of foods and supplements, and engaging in specific sustainable food production and eating practices. However, to support self-sufficiency during long-term space exploration, the most optimal and sustainable space nutrition systems are likely to be supported primarily by fresh food production, natural unprocessed foods as diets, nutrient recycling of food scraps and cultivation systems, and the establishment of closed-loop biospheres or landscape-based space habitats as long-term life support systems.
Collapse
Affiliation(s)
- Hong Tang
- College of Landscape and Tourism, Gansu Agricultural University, Lanzhou 730070, China;
| | - Hope Hui Rising
- Department of Landscape Architecture and Urban Planning, Texas A&M University, College Station, TX 77843, USA;
- Correspondence:
| | - Manoranjan Majji
- Department of Aerospace Engineering, Texas A&M University, College Station, TX 77843, USA;
| | - Robert D. Brown
- Department of Landscape Architecture and Urban Planning, Texas A&M University, College Station, TX 77843, USA;
| |
Collapse
|
14
|
Bychkov A, Reshetnikova P, Bychkova E, Podgorbunskikh E, Koptev V. The current state and future trends of space nutrition from a perspective of astronauts' physiology. Int J Gastron Food Sci 2021. [DOI: 10.1016/j.ijgfs.2021.100324] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
|
15
|
Yang F, Liu Y, Chen S, Dai Z, Yang D, Gao D, Shao J, Wang Y, Wang T, Zhang Z, Zhang L, Lu WW, Li Y, Wang L. A GABAergic neural circuit in the ventromedial hypothalamus mediates chronic stress-induced bone loss. J Clin Invest 2021; 130:6539-6554. [PMID: 32910804 DOI: 10.1172/jci136105] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2020] [Accepted: 08/26/2020] [Indexed: 12/25/2022] Open
Abstract
Homeostasis of bone metabolism is regulated by the central nervous system, and mood disorders such as anxiety are associated with bone metabolism abnormalities, yet our understanding of the central neural circuits regulating bone metabolism is limited. Here, we demonstrate that chronic stress in crewmembers resulted in decreased bone density and elevated anxiety in an isolated habitat mimicking a space station. We then used a mouse model to demonstrate that GABAergic neural circuitry in the ventromedial hypothalamus (VMH) mediates chronic stress-induced bone loss. We show that GABAergic inputs in the dorsomedial VMH arise from a specific group of somatostatin neurons in the posterior region of the bed nucleus of the stria terminalis, which is indispensable for stress-induced bone loss and is able to trigger bone loss in the absence of stressors. In addition, the sympathetic system and glutamatergic neurons in the nucleus tractus solitarius were employed to regulate stress-induced bone loss. Our study has therefore identified the central neural mechanism by which chronic stress-induced mood disorders, such as anxiety, influence bone metabolism.
Collapse
Affiliation(s)
- Fan Yang
- Brain Cognition and Brain Disease Institute, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences (CAS).,CAS Key Laboratory of Brain Connectome and Manipulation.,Guangdong Provincial Key Laboratory of Brain Connectome and Behavior.,Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Yunhui Liu
- Brain Cognition and Brain Disease Institute, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences (CAS).,CAS Key Laboratory of Brain Connectome and Manipulation.,Guangdong Provincial Key Laboratory of Brain Connectome and Behavior.,Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Shanping Chen
- Brain Cognition and Brain Disease Institute, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences (CAS).,CAS Key Laboratory of Brain Connectome and Manipulation.,Guangdong Provincial Key Laboratory of Brain Connectome and Behavior.,Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Zhongquan Dai
- State Key Laboratory of Space Medicine Fundamentals and Application, China Astronaut Research and Training Center, Beijing, China
| | - Dazhi Yang
- Department of Orthopedics, Union Shenzhen Hospital, Huazhong University of Science and Technology, Shenzhen, China
| | - Dashuang Gao
- Brain Cognition and Brain Disease Institute, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences (CAS).,CAS Key Laboratory of Brain Connectome and Manipulation.,Guangdong Provincial Key Laboratory of Brain Connectome and Behavior.,Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Jie Shao
- Brain Cognition and Brain Disease Institute, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences (CAS).,CAS Key Laboratory of Brain Connectome and Manipulation.,Guangdong Provincial Key Laboratory of Brain Connectome and Behavior.,Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Yuyao Wang
- Brain Cognition and Brain Disease Institute, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences (CAS).,CAS Key Laboratory of Brain Connectome and Manipulation.,Guangdong Provincial Key Laboratory of Brain Connectome and Behavior.,Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen, China
| | - Ting Wang
- Brain Cognition and Brain Disease Institute, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences (CAS).,CAS Key Laboratory of Brain Connectome and Manipulation.,Guangdong Provincial Key Laboratory of Brain Connectome and Behavior.,Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen, China
| | - Zhijian Zhang
- Center for Brain Science, Key Laboratory of Magnetic Resonance in Biological Systems and State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, CAS, Wuhan, China.,Center for Excellence in Brain Science and Intelligence Technology, CAS, Shanghai, China
| | - Lu Zhang
- Department of Orthopaedics and Traumatology, The University of Hong Kong, Hong Kong, China
| | - William W Lu
- Department of Orthopaedics and Traumatology, The University of Hong Kong, Hong Kong, China
| | - Yinghui Li
- State Key Laboratory of Space Medicine Fundamentals and Application, China Astronaut Research and Training Center, Beijing, China
| | - Liping Wang
- Brain Cognition and Brain Disease Institute, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences (CAS).,CAS Key Laboratory of Brain Connectome and Manipulation.,Guangdong Provincial Key Laboratory of Brain Connectome and Behavior.,Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen, China.,University of Chinese Academy of Sciences, Beijing, China
| |
Collapse
|
16
|
Scott JPR, Kramer A, Petersen N, Green DA. The Role of Long-Term Head-Down Bed Rest in Understanding Inter-Individual Variation in Response to the Spaceflight Environment: A Perspective Review. Front Physiol 2021; 12:614619. [PMID: 33643065 PMCID: PMC7904881 DOI: 10.3389/fphys.2021.614619] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Accepted: 01/04/2021] [Indexed: 12/12/2022] Open
Abstract
Exposure to the spaceflight environment results in profound multi-system physiological adaptations in which there appears to be substantial inter-individual variability (IV) between crewmembers. However, performance of countermeasure exercise renders it impossible to separate the effects of the spaceflight environment alone from those associated with exercise, whilst differences in exercise programs, spaceflight operations constraints, and environmental factors further complicate the interpretation of IV. In contrast, long-term head-down bed rest (HDBR) studies isolate (by means of a control group) the effects of mechanical unloading from those associated with countermeasures and control many of the factors that may contribute to IV. In this perspective, we review the available evidence of IV in response to the spaceflight environment and discuss factors that complicate its interpretation. We present individual data from two 60-d HDBR studies that demonstrate that, despite the highly standardized experimental conditions, marked quantitative differences still exist in the response of the cardiorespiratory and musculoskeletal systems between individuals. We also discuss the statistical concept of “true” and “false” individual differences and its potential application to HDBR data. We contend that it is currently not possible to evaluate IV in response to the spaceflight environment and countermeasure exercise. However, with highly standardized experimental conditions and the presence of a control group, HDBR is suitable for the investigation of IV in the physiological responses to gravitational unloading and countermeasures. Such investigations may provide valuable insights into the potential role of IV in adaptations to the spaceflight environment and the effectiveness of current and future countermeasures.
Collapse
Affiliation(s)
- Jonathan P R Scott
- Space Medicine Team, ISS Operations and Astronaut Group, Directorate of Human and Robotic Exploration, European Space Agency, Cologne, Germany.,KBR GmbH, Cologne, Germany
| | - Andreas Kramer
- Department of Sport Science, University of Konstanz, Konstanz, Germany
| | - Nora Petersen
- Space Medicine Team, ISS Operations and Astronaut Group, Directorate of Human and Robotic Exploration, European Space Agency, Cologne, Germany.,KBR GmbH, Cologne, Germany
| | - David A Green
- Space Medicine Team, ISS Operations and Astronaut Group, Directorate of Human and Robotic Exploration, European Space Agency, Cologne, Germany.,KBR GmbH, Cologne, Germany.,Centre of Human and Applied Physiology, King's College London, London, United Kingdom
| |
Collapse
|
17
|
Palacios S, Caiani EG, Landreani F, Martínez JP, Pueyo E. Long-Term Microgravity Exposure Increases ECG Repolarization Instability Manifested by Low-Frequency Oscillations of T-Wave Vector. Front Physiol 2019; 10:1510. [PMID: 31920714 PMCID: PMC6928004 DOI: 10.3389/fphys.2019.01510] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Accepted: 11/29/2019] [Indexed: 11/13/2022] Open
Abstract
Ventricular arrhythmias and sudden cardiac death during long-term space missions are a major concern for space agencies. Long-duration spaceflight and its ground-based analog head-down bed rest (HDBR) have been reported to markedly alter autonomic and cardiac functioning, particularly affecting ventricular repolarization of the electrocardiogram (ECG). In this study, novel methods are developed, departing from previously published methodologies, to quantify the index of Periodic Repolarization Dynamics (PRD), an arrhythmic risk marker that characterizes sympathetically-mediated low-frequency oscillations in the T-wave vector. PRD is evaluated in ECGs from 42 volunteers at rest and during an orthostatic tilt table test recorded before and after 60-day –6° HDBR. Our results indicate that tilt test, on top of enhancing sympathetic regulation of heart rate, notably increases PRD, both before and after HDBR, thus supporting previous evidence on PRD being an indicator of sympathetic modulation of ventricular repolarization. Importantly, long-term microgravity exposure is shown to lead to significant increases in PRD, both when evaluated at rest and, even more notably, in response to tilt test. The extent of microgravity-induced changes in PRD has been associated with arrhythmic risk in prior studies. An exercise-based, but not a nutrition-based, countermeasure is able to partially reverse microgravity-induced effects on PRD. In conclusion, long-term exposure to microgravity conditions leads to elevated low-frequency oscillations of ventricular repolarization, which are potentiated following sympathetic stimulation and are related to increased risk for repolarization instabilities and arrhythmias. Tested countermeasures are only partially effective in counteracting microgravity effects.
Collapse
Affiliation(s)
- Saúl Palacios
- BSICoS Group, Aragón Institute of Engineering Research, IIS Aragón, Universidad de Zaragoza, Zaragoza, Spain
| | - Enrico G Caiani
- Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, Milan, Italy
| | - Federica Landreani
- Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, Milan, Italy
| | - Juan Pablo Martínez
- BSICoS Group, Aragón Institute of Engineering Research, IIS Aragón, Universidad de Zaragoza, Zaragoza, Spain.,CIBER en Bioingeniería, Biomateriales y Nanomedicina, Madrid, Spain
| | - Esther Pueyo
- BSICoS Group, Aragón Institute of Engineering Research, IIS Aragón, Universidad de Zaragoza, Zaragoza, Spain.,CIBER en Bioingeniería, Biomateriales y Nanomedicina, Madrid, Spain
| |
Collapse
|
18
|
McDonnell AC, Eiken O, Frings-Meuthen P, Rittweger J, Mekjavic IB. The LunHab project: Muscle and bone alterations in male participants following a 10 day lunar habitat simulation. Exp Physiol 2019; 104:1250-1261. [PMID: 31273869 DOI: 10.1113/ep087482] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Accepted: 05/07/2019] [Indexed: 12/24/2022]
Abstract
NEW FINDINGS What is the central question of this study? It is well established that muscle and bone atrophy in conditions of inactivity or unloading, but there is little information regarding the effect of a hypoxic environment on the time course of these deconditioning physiological systems. What is the main finding and its importance? The main finding is that a horizontal 10 day bed rest in normoxia results in typical muscle atrophy, which is not aggravated by hypoxia. Changes in bone mineral content or in metabolism were not detected after either normoxic or hypoxic bed rest. ABSTRACT Musculoskeletal atrophy constitutes a typical adaptation to inactivity and unloading of weightbearing bones. The reduced-gravity environment in future Moon and Mars habitats is likely to be hypobaric hypoxic, and there is an urgent need to understand the effect of hypoxia on the process of inactivity-induced musculoskeletal atrophy. This was the principal aim of the present study. Eleven males participated in three 10 day interventions: (i) hypoxic ambulatory confinement; (ii) hypoxic bed rest; and (iii) normoxic bed rest. Before and after the interventions, the muscle strength (isometric maximal voluntary contraction), mass (lean mass, by dual-energy X-ray absorptiometry), cross-sectional area and total bone mineral content (determined with peripheral quantitative computed tomography) of the participants were measured. Blood and urine samples were collected before and on the 1st, 4th and 10th day of the intervention and analysed for biomarkers of bone resorption and formation. There was a significant reduction in thigh and lower leg muscle mass and volume after both normoxic and hypoxic bed rests. Muscle strength loss was proportionately greater than the loss in muscle mass for both thigh and lower leg. There was no indication of bone loss. Furthermore, the biomarkers of resorption and formation were not affected by any of the interventions. There was no significant effect of hypoxia on the musculoskeletal variables. Short-term normoxic (10 day) bed rest resulted in muscular deconditioning, but not in the loss of bone mineral content or changes in bone metabolism. Hypoxia did not modify these results.
Collapse
Affiliation(s)
- Adam C McDonnell
- Department of Automation, Biocybernetics and Robotics, Institute Jozef Stefan, Ljubljana, Slovenia
| | - Ola Eiken
- Department of Environmental Physiology, School of Technology and Health, Royal Institute of Technology, Solna, Sweden
| | - Petra Frings-Meuthen
- Institute for Aerospace Medicine, German Aerospace Centre (DLR), Cologne, Germany
| | - Joern Rittweger
- Institute for Aerospace Medicine, German Aerospace Centre (DLR), Cologne, Germany.,Department of Paediatrics and Adolescent Medicine, University of Cologne, Cologne, Germany
| | - Igor B Mekjavic
- Department of Automation, Biocybernetics and Robotics, Institute Jozef Stefan, Ljubljana, Slovenia.,Department of Biomedical Sciences and Kinesiology, Simon Fraser University, Burnaby, British Columbia, Canada
| |
Collapse
|
19
|
Laurens C, Simon C, Vernikos J, Gauquelin-Koch G, Blanc S, Bergouignan A. Revisiting the Role of Exercise Countermeasure on the Regulation of Energy Balance During Space Flight. Front Physiol 2019; 10:321. [PMID: 30984019 PMCID: PMC6449861 DOI: 10.3389/fphys.2019.00321] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Accepted: 03/11/2019] [Indexed: 01/24/2023] Open
Abstract
A body mass loss has been consistently observed in astronauts. This loss is of medical concern since energy deficit can exacerbate some of the deleterious physiological changes observed during space flight including cardiovascular deconditioning, bone density, muscle mass and strength losses, impaired exercise capacity, and immune deficiency among others. These may jeopardize crew health and performance, a healthy return to Earth and mission’s overall success. In the context of planning for planetary exploration, achieving energy balance during long-term space flights becomes a research and operational priority. The regulation of energy balance and its components in current longer duration missions in space must be re-examined and fully understood. The purpose of this review is to summarize current understanding of how energy intake, energy expenditure, and hence energy balance are regulated in space compared to Earth. Data obtained in both actual and simulated microgravity thus far suggest that the obligatory exercise countermeasures program, rather than the microgravity per se, may be partly responsible for the chronic weight loss in space. Little is known of the energy intake, expenditure, and balance during the intense extravehicular activities which will become increasingly more frequent and difficult. The study of the impact of exercise on energy balance in space also provides further insights on lifestyle modalities such as intensity and frequency of exercise, metabolism, and the regulation of body weight on Earth, which is currently a topic of animated debate in the field of energy and obesity research. While not dismissing the significance of exercise as a countermeasure during space flight, data now challenge the current exercise countermeasure program promoted and adopted for many years by all the International Space Agencies. An alternative exercise approach that has a minimum impact on total energy expenditure in space, while preventing muscle mass loss and other physiological changes, is needed in order to better understand the in-flight regulation of energy balance and estimate daily energy requirements. A large body of data generated on Earth suggests that alternate approaches, such as high intensity interval training (HIIT), in combination or not with sessions of resistive exercise, might fulfill such needs.
Collapse
Affiliation(s)
- Claire Laurens
- Université de Strasbourg, Centre National de la Recherche Scientifique, Institut Pluridisciplinaire Hubert Curien UMR 7178, Strasbourg, France.,Centre National d'Etudes Spatiales, Paris, France
| | - Chantal Simon
- Carmen INSERM U1060, Laboratoire de Recherche en Cardiovasculaire, Métabolisme, Diabétologie et Nutrition, Université de Lyon, Lyon, France.,Human Nutrition Research Centre of Rhône-Alpes, Hospices Civils de Lyon, Lyon, France
| | | | | | - Stéphane Blanc
- Université de Strasbourg, Centre National de la Recherche Scientifique, Institut Pluridisciplinaire Hubert Curien UMR 7178, Strasbourg, France
| | - Audrey Bergouignan
- Université de Strasbourg, Centre National de la Recherche Scientifique, Institut Pluridisciplinaire Hubert Curien UMR 7178, Strasbourg, France.,Anschutz Health and Wellness Center, Anschutz Medical Campus, Aurora, CO, United States.,Division of Endocrinology, Metabolism and Diabetes, University of Colorado, Anschutz Medical Campus, Aurora, CO, United States
| |
Collapse
|
20
|
Hip load capacity cut-points for Astronaut Skeletal Health NASA Finite Element Strength Task Group Recommendations. NPJ Microgravity 2019; 5:6. [PMID: 30886891 PMCID: PMC6418107 DOI: 10.1038/s41526-019-0066-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Accepted: 02/06/2019] [Indexed: 11/09/2022] Open
Abstract
Concerns raised at a 2010 Bone Summit held for National Aeronautics and Space Administration Johnson Space Center led experts in finite element (FE) modeling for hip fracture prediction to propose including hip load capacity in the standards for astronaut skeletal health. The current standards for bone are based upon areal bone mineral density (aBMD) measurements by dual X-ray absorptiometry (DXA) and an adaptation of aBMD cut-points for fragility fractures. Task Group members recommended (i) a minimum permissible outcome limit (POL) for post-mission hip bone load capacity, (ii) use of FE hip load capacity to further screen applicants to astronaut corps, (iii) a minimum pre-flight standard for a second long-duration mission, and (iv) a method for assessing which post-mission physical activities might increase an astronaut’s risk for fracture after return. QCT-FE models of eight astronaut were analyzed using nonlinear single-limb stance (NLS) and posterolateral fall (NLF) loading configurations. QCT data from the Age Gene/Environment Susceptibility (AGES) Reykjavik cohort and the Rochester Epidemiology Project were analyzed using identical modeling procedures. The 75th percentile of NLS hip load capacity for fractured elderly males of the AGES cohort (9537N) was selected as a post-mission POL. The NLF model, in combination with a Probabilistic Risk Assessment tool, was used to assess the likelihood of exceeding the hip load capacity during post-flight activities. There was no recommendation to replace the current DXA-based standards. However, FE estimation of hip load capacity appeared more meaningful for younger, physically active astronauts and was recommended to supplement aBMD cut-points.
Collapse
|
21
|
Yang J, Zhang G, Dong D, Shang P. Effects of Iron Overload and Oxidative Damage on the Musculoskeletal System in the Space Environment: Data from Spaceflights and Ground-Based Simulation Models. Int J Mol Sci 2018; 19:E2608. [PMID: 30177626 PMCID: PMC6163331 DOI: 10.3390/ijms19092608] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Revised: 08/29/2018] [Accepted: 09/01/2018] [Indexed: 12/15/2022] Open
Abstract
The space environment chiefly includes microgravity and radiation, which seriously threatens the health of astronauts. Bone loss and muscle atrophy are the two most significant changes in mammals after long-term residency in space. In this review, we summarized current understanding of the effects of microgravity and radiation on the musculoskeletal system and discussed the corresponding mechanisms that are related to iron overload and oxidative damage. Furthermore, we enumerated some countermeasures that have a therapeutic potential for bone loss and muscle atrophy through using iron chelators and antioxidants. Future studies for better understanding the mechanism of iron and redox homeostasis imbalance induced by the space environment and developing the countermeasures against iron overload and oxidative damage consequently may facilitate human to travel more safely in space.
Collapse
Affiliation(s)
- Jiancheng Yang
- School of Life Sciences, Northwestern Polytechnical University, Xi'an 710072, China.
- Key Laboratory for Space Bioscience and Biotechnology, Institute of Special Environment Biophysics, Northwestern Polytechnical University, Xi'an 710072, China.
| | - Gejing Zhang
- School of Life Sciences, Northwestern Polytechnical University, Xi'an 710072, China.
- Key Laboratory for Space Bioscience and Biotechnology, Institute of Special Environment Biophysics, Northwestern Polytechnical University, Xi'an 710072, China.
| | - Dandan Dong
- School of Life Sciences, Northwestern Polytechnical University, Xi'an 710072, China.
- Key Laboratory for Space Bioscience and Biotechnology, Institute of Special Environment Biophysics, Northwestern Polytechnical University, Xi'an 710072, China.
| | - Peng Shang
- Key Laboratory for Space Bioscience and Biotechnology, Institute of Special Environment Biophysics, Northwestern Polytechnical University, Xi'an 710072, China.
- Research & Development Institute in Shenzhen, Northwestern Polytechnical University, Shenzhen 518057, China.
| |
Collapse
|
22
|
Crucian BE, Choukèr A, Simpson RJ, Mehta S, Marshall G, Smith SM, Zwart SR, Heer M, Ponomarev S, Whitmire A, Frippiat JP, Douglas GL, Lorenzi H, Buchheim JI, Makedonas G, Ginsburg GS, Ott CM, Pierson DL, Krieger SS, Baecker N, Sams C. Immune System Dysregulation During Spaceflight: Potential Countermeasures for Deep Space Exploration Missions. Front Immunol 2018; 9:1437. [PMID: 30018614 PMCID: PMC6038331 DOI: 10.3389/fimmu.2018.01437] [Citation(s) in RCA: 195] [Impact Index Per Article: 32.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Accepted: 06/11/2018] [Indexed: 12/11/2022] Open
Abstract
Recent studies have established that dysregulation of the human immune system and the reactivation of latent herpesviruses persists for the duration of a 6-month orbital spaceflight. It appears certain aspects of adaptive immunity are dysregulated during flight, yet some aspects of innate immunity are heightened. Interaction between adaptive and innate immunity also seems to be altered. Some crews experience persistent hypersensitivity reactions during flight. This phenomenon may, in synergy with extended duration and galactic radiation exposure, increase specific crew clinical risks during deep space exploration missions. The clinical challenge is based upon both the frequency of these phenomena in multiple crewmembers during low earth orbit missions and the inability to predict which specific individual crewmembers will experience these changes. Thus, a general countermeasure approach that offers the broadest possible coverage is needed. The vehicles, architecture, and mission profiles to enable such voyages are now under development. These include deployment and use of a cis-Lunar station (mid 2020s) with possible Moon surface operations, to be followed by multiple Mars flyby missions, and eventual human Mars surface exploration. Current ISS studies will continue to characterize physiological dysregulation associated with prolonged orbital spaceflight. However, sufficient information exists to begin consideration of both the need for, and nature of, specific immune countermeasures to ensure astronaut health. This article will review relevant in-place operational countermeasures onboard ISS and discuss a myriad of potential immune countermeasures for exploration missions. Discussion points include nutritional supplementation and functional foods, exercise and immunity, pharmacological options, the relationship between bone and immune countermeasures, and vaccination to mitigate herpes (and possibly other) virus risks. As the immune system has sentinel connectivity within every other physiological system, translational effects must be considered for all potential immune countermeasures. Finally, we shall discuss immune countermeasures in the context of their individualized implementation or precision medicine, based on crewmember specific immunological biases.
Collapse
Affiliation(s)
- Brian E. Crucian
- Biomedical Research and Environmental Sciences Division, NASA Johnson Space Center, Houston, TX, United States
| | - Alexander Choukèr
- Laboratory of Translational Research “Stress and Immunity”, Department of Anesthesiology, Hospital of the Ludwig-Maximilians-University, Munich, Germany
| | - Richard J. Simpson
- Department of Nutritional Sciences, The University of Arizona, Tucson, AZ, United States
- Department of Pediatrics, The University of Arizona, Tucson, AZ, United States
- Department of Immunobiology, The University of Arizona, Tucson, AZ, United States
| | | | - Gailen Marshall
- University of Mississippi Medical Center, Jackson, MS, United States
| | - Scott M. Smith
- Biomedical Research and Environmental Sciences Division, NASA Johnson Space Center, Houston, TX, United States
| | - Sara R. Zwart
- University of Texas Medical Branch, Galveston, TX, United States
| | - Martina Heer
- Institute of Nutritional and Food Sciences, University of Bonn, Bonn, Germany
| | | | | | - Jean P. Frippiat
- Stress Immunity Pathogens Laboratory, EA7300, Lorraine University, Nancy, France
| | - Grace L. Douglas
- Human Systems Engineering and Development Division, NASA Johnson Space Center, Houston, TX, United States
| | | | - Judith-Irina Buchheim
- Laboratory of Translational Research “Stress and Immunity”, Department of Anesthesiology, Hospital of the Ludwig-Maximilians-University, Munich, Germany
| | | | - Geoffrey S. Ginsburg
- Duke Center for Applied Genomics and Precision Medicine, Durham, NC, United States
| | - C. Mark Ott
- Biomedical Research and Environmental Sciences Division, NASA Johnson Space Center, Houston, TX, United States
| | - Duane L. Pierson
- Biomedical Research and Environmental Sciences Division, NASA Johnson Space Center, Houston, TX, United States
| | | | - Natalie Baecker
- Institute of Nutritional and Food Sciences, University of Bonn, Bonn, Germany
| | - Clarence Sams
- Biomedical Research and Environmental Sciences Division, NASA Johnson Space Center, Houston, TX, United States
| |
Collapse
|
23
|
Cromer WE, Zawieja DC. Acute exposure to space flight results in evidence of reduced lymph Transport, tissue fluid Shifts, and immune alterations in the rat gastrointestinal system. LIFE SCIENCES IN SPACE RESEARCH 2018; 17:74-82. [PMID: 29753416 DOI: 10.1016/j.lssr.2018.03.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Revised: 03/09/2018] [Accepted: 03/19/2018] [Indexed: 06/08/2023]
Abstract
Space flight causes a number of alterations in physiological systems, changes in the immunological status of subjects, and altered interactions of the host to environmental stimuli. We studied the effect of space flight on the lymphatic system of the gastrointestinal tract which is responsible for lipid transport and immune surveillance which includes the host interaction with the gut microbiome. We found that there were signs of tissue damage present in the space flown animals that was lacking in ground controls (epithelial damage, crypt morphological changes, etc.). Additionally, morphology of the lymphatic vessels in the tissue suggested a collapsed state at time of harvest and there was a profound change in the retention of lipid in the villi of the ileum. Contrary to our assumptions there was a reduction in tissue fluid volume likely associated with other fluid shifts described. The reduction of tissue fluid volume in the colon and ileum is a likely contributing factor to the state of the lymphatic vessels and lipid transport issues observed. There were also associated changes in the number of MHC-II+ immune cells in the colon tissue, which along with reduced lymphatic competence would favor immune dysfunction in the tissue. These findings help expand our understanding of the effects of space flight on various organ systems. It also points out potential issues that have not been closely examined and have to potential for the need of countermeasure development.
Collapse
Affiliation(s)
- W E Cromer
- Department of Medical Physiology, Texas A&M University Health Science Center, United States.
| | - D C Zawieja
- Department of Medical Physiology, Texas A&M University Health Science Center, United States
| |
Collapse
|
24
|
Tanaka K, Nishimura N, Kawai Y. Adaptation to microgravity, deconditioning, and countermeasures. J Physiol Sci 2017; 67:271-281. [PMID: 28000175 PMCID: PMC10717636 DOI: 10.1007/s12576-016-0514-8] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Accepted: 12/07/2016] [Indexed: 02/01/2023]
Abstract
Humans are generally in standing or sitting positions on Earth during the day. The musculoskeletal system supports these positions and also allows motion. Gravity acting in the longitudinal direction of the body generates a hydrostatic pressure difference and induces footward fluid shift. The vestibular system senses the gravity of the body and reflexively controls the organs. During spaceflight or exposure to microgravity, the load on the musculoskeletal system and hydrostatic pressure difference is diminished. Thus, the skeletal muscle, particularly in the lower limbs, is atrophied, and bone minerals are lost via urinary excretion. In addition, the heart is atrophied, and the plasma volume is decreased, which may induce orthostatic intolerance. Vestibular-related control also declines; in particular, the otolith organs are more susceptible to exposure to microgravity than the semicircular canals. Using an advanced resistive exercise device with administration of bisphosphonate is an effective countermeasure against bone deconditioning. However, atrophy of skeletal muscle and the heart has not been completely prevented. Further ingenuity is needed in designing countermeasures for muscular, cardiovascular, and vestibular dysfunctions.
Collapse
Affiliation(s)
- Kunihiko Tanaka
- Graduate School of Health and Medicine, Gifu University of Medical Science, 795-1 Nagamine Ichihiraga, Seki, Gifu, 501-3892, Japan.
| | - Naoki Nishimura
- Department of Physiology, Faculty of Medicine, Aichi Medical School, 1-1 Yazakokarimata, Nagakute, Aichi, 480-1103, Japan
| | - Yasuaki Kawai
- Division of Adaptation Physiology, Faculty of Medicine, Tottori University, 86 Nishi-machi, Yonago, Tottori, 683-8503, Japan
| |
Collapse
|
25
|
Debevec T, Simpson EJ, Mekjavic IB, Eiken O, Macdonald IA. Effects of prolonged hypoxia and bed rest on appetite and appetite-related hormones. Appetite 2016; 107:28-37. [PMID: 27395413 DOI: 10.1016/j.appet.2016.07.005] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Revised: 06/02/2016] [Accepted: 07/04/2016] [Indexed: 12/25/2022]
Abstract
Environmental hypoxia and inactivity have both been shown to modulate appetite. To elucidate the independent and combined effects of hypoxia and bed rest-induced inactivity on appetite-related hormones and subjective appetite, eleven healthy, non-obese males underwent three experimental interventions in a cross-over and randomized fashion: 1) Hypoxic confinement combined with daily moderate-intensity exercise (HAMB, FiO2 = 0.141 ± 0.004; PiO2 = 90.0 ± 0.4 mmHg) 2) Bed rest in normoxia (NBR, FiO2 = 0.209; PiO2 = 133.1 ± 0.3 mmHg) and 3) Bed rest in hypoxia (HBR, FiO2 = 0.141 ± 0.004; PiO2 = 90.0 ± 0.4 mmHg). A mixed-meal tolerance test (MTT), followed by an ad libitum meal were performed before (Pre) and after 16-days (Post) of each intervention. Composite satiety scores (CSS) during the MTT were calculated from visual analogue scores, while fasting and postprandial concentrations of total ghrelin, peptide YY (PYY), glucagon-like peptide-1 (GLP-1) and leptin were quantified from arterialized-venous samples. Postprandial CSS were significantly lower at Post compared to Pre in NBR only (P < 0.05) with no differences observed in ad libitum meal intakes. Postprandial concentrations and incremental area under the curve (AUC) for total ghrelin and PYY were unchanged following all interventions. Postprandial GLP-1 concentrations were only reduced at Post following HBR (P < 0.05) with resulting AUC changes being significantly lower compared to HAMB (P < 0.01). Fasting leptin was reduced following HAMB (P < 0.05) with no changes observed following NBR and HBR. These findings suggest that independently, 16-day of simulated altitude exposure (∼4000 m) and bed rest-induced inactivity do not significantly alter subjective appetite or ad libitum intakes. The measured appetite-related hormones following both HAMB and HBR point to a situation of hypoxia-induced appetite stimulation, although this did not reflect in higher ad libitum intakes. CLINICAL TRIAL REGISTRATION NUMBER NCT02293772.
Collapse
Affiliation(s)
- Tadej Debevec
- Department of Automation, Biocybernetics and Robotics, Jozef Stefan Institute, Ljubljana, Slovenia.
| | - Elizabeth J Simpson
- MRC/Arthritis Research UK Centre for Musculoskeletal Ageing Research, University of Nottingham Medical School, School of Life Sciences, Queen's Medical Centre, Nottingham, United Kingdom
| | - Igor B Mekjavic
- Department of Automation, Biocybernetics and Robotics, Jozef Stefan Institute, Ljubljana, Slovenia
| | - Ola Eiken
- Department of Environmental Physiology, Swedish Aerospace Physiology Centre, Royal Institute of Technology, Stockholm, Sweden
| | - Ian A Macdonald
- MRC/Arthritis Research UK Centre for Musculoskeletal Ageing Research, University of Nottingham Medical School, School of Life Sciences, Queen's Medical Centre, Nottingham, United Kingdom
| |
Collapse
|
26
|
Hackney KJ, Scott JM, Hanson AM, English KL, Downs ME, Ploutz-Snyder LL. The Astronaut-Athlete. J Strength Cond Res 2015; 29:3531-45. [DOI: 10.1519/jsc.0000000000001191] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
|
27
|
Prakash M, Fried R, Götze O, May F, Frings-Meuthen P, Mulder E, Valentini J, Fox M, Fried M, Schwizer W, Misselwitz B. Microgravity Simulated by the 6° Head-Down Tilt Bed Rest Test Increases Intestinal Motility but Fails to Induce Gastrointestinal Symptoms of Space Motion Sickness. Dig Dis Sci 2015; 60:3053-61. [PMID: 26055239 DOI: 10.1007/s10620-015-3738-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/09/2015] [Accepted: 05/28/2015] [Indexed: 12/09/2022]
Abstract
BACKGROUND Space motion sickness (SMS) is the most relevant medical problem during the first days in microgravity. Studies addressing pathophysiology in space face severe technical challenges and microgravity is frequently simulated using the 6° head-down tilt bed rest test (HDT). AIM We were aiming to test whether SMS could be simulated by HDT, identify related changes in gastrointestinal physiology and test for beneficial effects of exercise interventions. METHODS HDT was performed in ten healthy individuals. Each individual was tested in three study campaigns varying by a 30-min daily exercise intervention of either standing, an upright exercise regimen, or no intervention. Gastrointestinal symptoms, stool characteristics, gastric emptying time, and small intestinal transit were assessed using standardized questionnaires, (13)C octanoate breath test, and H2 lactulose breath test, respectively, before and at day 2 and 5 of HDT. RESULTS Individuals described no or minimal gastrointestinal symptoms during HDT. Gastric emptying remained unchanged relative to baseline data collection (BDC). At day 2 of HDT the H₂ peak of the lactulose test appeared earlier (mean ± standard error for BDC-1, HDT2, HDT5: 198 ± 7, 139 ± 18, 183 ± 10 min; p: 0.040), indicating accelerated small intestinal transit. Furthermore, during HDT, stool was softer and stool mass increased (BDC: 47 ± 6, HDT: 91 ± 12, recovery: 53 ± 8 g/day; p: 0.014), indicating accelerated colonic transit. Exercise interventions had no effect. CONCLUSION HDT did not induce symptoms of SMS. During HDT, gastric emptying remained unchanged, but small and large intestinal transit was accelerated.
Collapse
Affiliation(s)
- Meher Prakash
- Division of Gastroenterology and Hepatology, University Hospital Zurich and Zurich University, Rämistr. 100, 8091, Zurich, Switzerland
| | - Ron Fried
- Division of Gastroenterology and Hepatology, University Hospital Zurich and Zurich University, Rämistr. 100, 8091, Zurich, Switzerland
| | - Oliver Götze
- Division of Hepatology, Department of Medicine II, University Hospital Würzburg, Würzburg, Germany
| | - Francisca May
- Institute of Aerospace Medicine, German Aerospace Center (DLR), Cologne, Germany
| | - Petra Frings-Meuthen
- Institute of Aerospace Medicine, German Aerospace Center (DLR), Cologne, Germany
| | - Edwin Mulder
- Institute of Aerospace Medicine, German Aerospace Center (DLR), Cologne, Germany
| | - Judit Valentini
- Swiss Center of Excellence for Agricultural Research (Agroscope), Bern, Switzerland
| | - Mark Fox
- Division of Gastroenterology and Hepatology, University Hospital Zurich and Zurich University, Rämistr. 100, 8091, Zurich, Switzerland.,Zurich Integrative Human Physiology Group, University of Zurich, Zurich, Switzerland
| | - Michael Fried
- Division of Gastroenterology and Hepatology, University Hospital Zurich and Zurich University, Rämistr. 100, 8091, Zurich, Switzerland.,Zurich Integrative Human Physiology Group, University of Zurich, Zurich, Switzerland
| | - Werner Schwizer
- Division of Gastroenterology and Hepatology, University Hospital Zurich and Zurich University, Rämistr. 100, 8091, Zurich, Switzerland.,Zurich Integrative Human Physiology Group, University of Zurich, Zurich, Switzerland
| | - Benjamin Misselwitz
- Division of Gastroenterology and Hepatology, University Hospital Zurich and Zurich University, Rämistr. 100, 8091, Zurich, Switzerland.
| |
Collapse
|
28
|
|
29
|
Morgan JLL, Heer M, Hargens AR, Macias BR, Hudson EK, Shackelford LC, Zwart SR, Smith SM. Sex-specific responses of bone metabolism and renal stone risk during bed rest. Physiol Rep 2014; 2:2/8/e12119. [PMID: 25107989 PMCID: PMC4246590 DOI: 10.14814/phy2.12119] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
The purpose of this study was to directly assess sex differences in bone loss, bone biochemistry, and renal stone risk in bed rest. Bed rest simulates some spaceflight effects on human physiology and can be used to address the potential existence of sex‐specific effects on bone metabolism and renal stone risk in space. We combined data from the control subjects in five head‐down‐tilt bed rest studies (combined n = 50 men, 24 women) of differing durations (14–90 days). All subjects were healthy volunteers. Mean age was 35 ± 9 years for women and 33 ± 8 years for men. The main outcome measures were bone density and biochemistry, and renal stone risk chemistry. Before bed rest began, men had higher bone mineral density and content (P < 0.001), and excreted more biomarkers of bone resorption and calcium per day than did women (P < 0.05). These differences remained during bed rest. A number of urine chemistry analytes increased (e.g., calcium) or decreased (e.g., sodium, citrate, and urine volume) significantly for men and women during bed rest. These changes may predispose men to higher stone risk. Men and women do not have substantially different responses to the skeletal unloading of bed rest. We report here that bed rest‐induced bone loss, bone biochemistry, and renal stone risk in humans does not depend on sex. These data are a compilation and analysis of original data from our multiple (published) studies; none of those were adequately powered to assess sex differences. Thus, the resulting findings provide an important new look at the data.
Collapse
Affiliation(s)
- Jennifer L L Morgan
- Oak Ridge Associated Universities/NASA, NASA Johnson Space Center, Houston, Texas, USA
| | - Martina Heer
- Institute of Nutritional Physiology, University of Bonn, Bonn, Germany
| | - Alan R Hargens
- University of California San Diego, San Diego, California, USA
| | | | - Edgar K Hudson
- JES Tech, NASA Johnson Space Center, Houston, Texas, USA
| | | | - Sara R Zwart
- Universities Space Research Association, Houston, Texas, USA
| | - Scott M Smith
- NASA, NASA Johnson Space Center, Houston, Texas, USA
| |
Collapse
|
30
|
Debevec T, Bali TC, Simpson EJ, Macdonald IA, Eiken O, Mekjavic IB. Separate and combined effects of 21-day bed rest and hypoxic confinement on body composition. Eur J Appl Physiol 2014; 114:2411-25. [PMID: 25091855 DOI: 10.1007/s00421-014-2963-1] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Accepted: 07/18/2014] [Indexed: 10/24/2022]
Abstract
PURPOSE This study tested the hypothesis that hypoxia exacerbates reductions in body mass observed during unloading. METHODS To discern the separate and combined effects of simulated microgravity and hypoxia, 11 healthy males underwent three 21-day campaigns in a counterbalanced fashion: (1) normoxic bed rest (NBR; FiO₂ = 0.209; PiO₂ = 133.1 ± 0.3); (2) hypoxic ambulatory confinement (HAMB; FiO₂ = 0.141 ± 0.004; PiO₂ = 90.0 ± 0.4; ~4,000 m); and (3) hypoxic bed rest (HBR; FiO₂ = 0.141 ± 0.004; PiO₂ = 90.0 ± 0.4). The same dietary menu was applied in all campaigns. Targeted energy intakes were estimated individually using the Harris-Benedict equation taking into account whether the subjects were bedridden or ambulatory. Body mass and water balance were assessed throughout the campaigns. Whole body and regional body composition was determined before and after the campaigns using dual-energy X-ray absorptiometry. Before and during the campaigns, indirect calorimetry and visual analogue scores were employed to assess the resting energy expenditure (REE) and perceived appetite sensations, respectively. RESULTS Energy intakes were lower than targeted in all campaigns (NBR: -5%; HAMB: -14%; HBR: -6%; P < 0.01). Body mass significantly decreased following all campaigns (NBR: -3%; HAMB: -4%; HBR: -5%; P < 0.01). While fat mass was not significantly altered, the whole body fat free mass was reduced (NBR: -4%; HAMB: -5%; HBR: -5%; P < 0.01), secondary to lower limb fat-free mass reduction. Water balance was comparable between the campaigns. No changes were observed in REE and perceived appetite. CONCLUSIONS Exposure to simulated altitude of ~4,000 m does not seem to worsen the whole body mass and fat-free mass reductions or alter resting energy expenditure and appetite during a 21-day simulated microgravity.
Collapse
Affiliation(s)
- Tadej Debevec
- Department of Automation, Biocybernetics and Robotics, Jozef Stefan Institute, Jamova 39, 1000, Ljubljana, Slovenia,
| | | | | | | | | | | |
Collapse
|
31
|
Kouhnavard M, Nasli Esfahani E, Montazeri M, Hashemian SJ, Mehrazma M, Larijani B, Nezami Asl A, Khoshvaghti A, Falsafi A, Lalehfar K, Malekpour K, Vosugh M. Effects of Vitamin D and Calcium Supplementation on Micro-architectural and Densitometric Changes of Rat Femur in a Microgravity Simulator Model. IRANIAN RED CRESCENT MEDICAL JOURNAL 2014; 16:e18026. [PMID: 25068054 PMCID: PMC4102987 DOI: 10.5812/ircmj.18026] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/04/2014] [Revised: 03/06/2014] [Accepted: 04/07/2014] [Indexed: 11/22/2022]
Abstract
Background: Revealing data on the role of vitamin D and calcium supplementation in bone health has led some to suggest that vitamin D and calcium treatment could also play a role in protecting bone against microgravity-induced mineral loss. Objectives: The aim of the present study was to investigate the effects of vitamin D and calcium administration on microscopic and densitometric changes of rat femur in a Microgravity Simulator Model. Materials and Methods: After designing a Microgravity Simulator Model, 14 rats were placed in the cages as follows: seven rats as osteoporosis group and seven rats received oral supplement of calcium/vitamin D as the treatment group. Animals were sacrificed after eight weeks and then both femurs were removed. Bone mineral density was measured for one femur from each animal, and morphologic studies were evaluated for the contralateral femur. Results: Bone mineral density of the whole femur in the treatment group was significantly higher than the osteoporosis group (0.168 ± 0.005 vs. 0.153 ± 0.006, P = 0.003). Also, bone mineral content of the whole femur was significantly higher in treatment group (0.415 ± 0.016 vs. 0.372 ± 0.019, P = 0.003). However, resorption eroded surface percentage was higher in the osteoporosis group (18.86 ± 3.71% vs. 9.71 ± 1.61%, P = 0.002). Conclusions: According to the results of this study, vitamin D and calcium administration might have protective effects against microgravity-induced mineral loss in a Rat Microgravity Simulator Model.
Collapse
Affiliation(s)
- Marjan Kouhnavard
- Diabetes Research Center, Endocrinology and Metabolism Clinical Sciences Institute, Tehran University of Medical Sciences , Tehran, IR Iran
- Endocrinology and Metabolism Research Center, Endocrinology and Metabolism Research Institute, Tehran University of Medical Sciences, Tehran , IR Iran
| | - Ensieh Nasli Esfahani
- Diabetes Research Center, Endocrinology and Metabolism Clinical Sciences Institute, Tehran University of Medical Sciences , Tehran, IR Iran
- Endocrinology and Metabolism Research Center, Endocrinology and Metabolism Research Institute, Tehran University of Medical Sciences, Tehran , IR Iran
| | | | - Seyed Jafar Hashemian
- Diabetes Research Center, Endocrinology and Metabolism Clinical Sciences Institute, Tehran University of Medical Sciences , Tehran, IR Iran
- Endocrinology and Metabolism Research Center, Endocrinology and Metabolism Research Institute, Tehran University of Medical Sciences, Tehran , IR Iran
- Corresponding Author: Seyed Jafar Hashemian, Diabetes Research Center, Endocrinology and Metabolism Clinical Sciences Institute, Tehran University of Medical Sciences , Tehran, IR Iran. Tel: +98-2188220037, Fax: +98-2188220052, E-mail:
| | - Mitra Mehrazma
- Oncopathology Research Center, Iran University of Medical Sciences, Tehran, IR Iran
| | - Bagher Larijani
- Endocrinology and Metabolism Research Center, Endocrinology and Metabolism Research Institute, Tehran University of Medical Sciences, Tehran , IR Iran
| | - Amir Nezami Asl
- Aerospace and Subaquatic Medicine Faculty, AJA University of Medical Sciences, Tehran, IR Iran
| | - Amir Khoshvaghti
- Aerospace and Subaquatic Medicine Faculty, AJA University of Medical Sciences, Tehran, IR Iran
| | - Ammar Falsafi
- Diabetes Research Center, Endocrinology and Metabolism Clinical Sciences Institute, Tehran University of Medical Sciences , Tehran, IR Iran
| | - Komeil Lalehfar
- Diabetes Research Center, Endocrinology and Metabolism Clinical Sciences Institute, Tehran University of Medical Sciences , Tehran, IR Iran
| | - Keyvan Malekpour
- Diabetes Research Center, Endocrinology and Metabolism Clinical Sciences Institute, Tehran University of Medical Sciences , Tehran, IR Iran
| | - Mehran Vosugh
- Diabetes Research Center, Endocrinology and Metabolism Clinical Sciences Institute, Tehran University of Medical Sciences , Tehran, IR Iran
| |
Collapse
|
32
|
Hackney KJ, English KL. Protein and Essential Amino Acids to Protect Musculoskeletal Health during Spaceflight: Evidence of a Paradox? Life (Basel) 2014; 4:295-317. [PMID: 25370374 PMCID: PMC4206848 DOI: 10.3390/life4030295] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2014] [Revised: 06/19/2014] [Accepted: 06/23/2014] [Indexed: 11/17/2022] Open
Abstract
Long-duration spaceflight results in muscle atrophy and a loss of bone mineral density. In skeletal muscle tissue, acute exercise and protein (e.g., essential amino acids) stimulate anabolic pathways (e.g., muscle protein synthesis) both independently and synergistically to maintain neutral or positive net muscle protein balance. Protein intake in space is recommended to be 12%-15% of total energy intake (≤1.4 g∙kg-1∙day-1) and spaceflight is associated with reduced energy intake (~20%), which enhances muscle catabolism. Increasing protein intake to 1.5-2.0 g∙kg-1∙day-1 may be beneficial for skeletal muscle tissue and could be accomplished with essential amino acid supplementation. However, increased consumption of sulfur-containing amino acids is associated with increased bone resorption, which creates a dilemma for musculoskeletal countermeasures, whereby optimizing skeletal muscle parameters via essential amino acid supplementation may worsen bone outcomes. To protect both muscle and bone health, future unloading studies should evaluate increased protein intake via non-sulfur containing essential amino acids or leucine in combination with exercise countermeasures and the concomitant influence of reduced energy intake.
Collapse
Affiliation(s)
- Kyle J Hackney
- Department of Health, Nutrition, and Exercise Sciences, North Dakota State University, Fargo, ND 58102, USA.
| | - Kirk L English
- Exercise Physiology and Countermeasures Laboratory, JES Tech, Houston, TX 77058, USA.
| |
Collapse
|
33
|
Smith SM, Zwart SR, Heer M, Hudson EK, Shackelford L, Morgan JL. Men and women in space: bone loss and kidney stone risk after long-duration spaceflight. J Bone Miner Res 2014; 29:1639-45. [PMID: 24470067 DOI: 10.1002/jbmr.2185] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/21/2013] [Revised: 01/14/2014] [Accepted: 01/20/2014] [Indexed: 11/08/2022]
Abstract
Bone loss, a key concern for long-duration space travelers, is typically considered a female issue. The number of women who have flown long-duration space missions is now great enough to allow a quantitative comparison of changes in bone and renal stone risk by sex. Participants were 42 astronauts (33 men and 9 women) on long-duration missions to the International Space Station. Bone mineral density (by dual-energy X-ray absorptiometry) and biochemical markers of bone metabolism (from blood and urine samples) were evaluated before and after flight. Data were analyzed in two groups, based on available resistance exercise equipment. Missions were 49 to 215 days in duration, flown between 2000 and 2012. The bone density response to spaceflight was the same for men and women in both exercise groups. The bone mineral density response to flight was the same for men and women, and the typical decrease in bone mineral density (whole body and/or regional) after flight was not observed for either sex for those using an advanced resistive exercise device. Biochemical markers of bone formation and resorption responded similarly in male and female astronauts. The response of urinary supersaturation risk to spaceflight was not significantly different between men and women, although risks were typically increased after flight in both groups, and risks were greater in men than in women before and after flight. The responses of men and women to spaceflight with respect to these measures of bone health were not different.
Collapse
Affiliation(s)
- Scott M Smith
- Human Health and Performance Directorate, NASA Lyndon B. Johnson Space Center, Houston, TX, USA
| | | | | | | | | | | |
Collapse
|
34
|
Debevec T, McDonnell AC, Macdonald IA, Eiken O, Mekjavic IB. Whole body and regional body composition changes following 10-day hypoxic confinement and unloading–inactivity. Appl Physiol Nutr Metab 2014; 39:386-95. [DOI: 10.1139/apnm-2013-0278] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Future planetary habitats will expose inhabitants to both reduced gravity and hypoxia. This study investigated the effects of short-term unloading and normobaric hypoxia on whole body and regional body composition (BC). Eleven healthy, recreationally active, male participants with a mean (SD) age of 24 (2) years and body mass index of 22.4 (3.2) kg·m−2 completed the following 3 10-day campaigns in a randomised, cross-over designed protocol: (i) hypoxic ambulatory confinement (HAMB; FIO2 = 0.147 (0.008); PIO2 = 93.8 (0.9) mm Hg), (ii) hypoxic bed rest (HBR; FIO2 = 0.147 (0.008); PIO2 = 93.8 (0.9) mm Hg), and (iii) normoxic bed rest (NBR; FIO2 = 0.209; PIO2 = 133.5 (0.7) mm Hg). Nutritional requirements were individually precalculated and the actual intake was monitored throughout the study protocol. Body mass, whole body, and regional BC were assessed before and after the campaigns using dual-energy X-ray absorptiometry. The calculated daily targeted energy intake values were 2071 (170) kcal for HBR and NBR and 2417 (200) kcal for HAMB. In both HBR and NBR campaigns the actual energy intake was within the targeted level, whereas in the HAMB the intake was lower than targeted (–8%, p < 0.05). Body mass significantly decreased in all 3 campaigns (–2.1%, –2.8%, and –2.0% for HAMB, HBR, and NBR, respectively; p < 0.05), secondary to a significant decrease in lean mass (–3.8%, –3.8%, –4.3% for HAMB, HBR, and NBR, respectively; p < 0.05) along with a slight, albeit not significant, increase in fat mass. The same trend was observed in the regional BC regardless of the region and the campaign. These results demonstrate that, hypoxia per se, does not seem to alter whole body and regional BC during short-term bed rest.
Collapse
Affiliation(s)
- Tadej Debevec
- Department of Automation, Biocybernetics and Robotics, Jozef Stefan Institute, Jamova 39, SI-1000 Ljubljana, Slovenia
| | - Adam C. McDonnell
- Department of Automation, Biocybernetics and Robotics, Jozef Stefan Institute, Jamova 39, SI-1000 Ljubljana, Slovenia
- Jozef Stefan International Postgraduate School, Jamova 39, Ljubljana, Slovenia
| | - Ian A. Macdonald
- MRC/Arthritis Research UK Centre for Musculoskeletal Ageing Research, University of Nottingham Medical School, School of Life Sciences, Queen’s Medical Centre, Nottingham NG7 2UH, United Kingdom
| | - Ola Eiken
- Department of Environmental Physiology, School of Technology and Health, KTH Royal Institute of Technology, Berzelius v. 13, Stockholm, Sweden
| | - Igor B. Mekjavic
- Department of Automation, Biocybernetics and Robotics, Jozef Stefan Institute, Jamova 39, SI-1000 Ljubljana, Slovenia
| |
Collapse
|
35
|
Orwoll ES, Adler RA, Amin S, Binkley N, Lewiecki EM, Petak SM, Shapses SA, Sinaki M, Watts NB, Sibonga JD. Skeletal health in long-duration astronauts: nature, assessment, and management recommendations from the NASA Bone Summit. J Bone Miner Res 2013; 28:1243-55. [PMID: 23553962 DOI: 10.1002/jbmr.1948] [Citation(s) in RCA: 106] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2012] [Revised: 03/04/2013] [Accepted: 03/20/2013] [Indexed: 11/09/2022]
Abstract
Concern about the risk of bone loss in astronauts as a result of prolonged exposure to microgravity prompted the National Aeronautics and Space Administration to convene a Bone Summit with a panel of experts at the Johnson Space Center to review the medical data and research evidence from astronauts who have had prolonged exposure to spaceflight. Data were reviewed from 35 astronauts who had served on spaceflight missions lasting between 120 and 180 days with attention focused on astronauts who (1) were repeat fliers on long-duration missions, (2) were users of an advanced resistive exercise device (ARED), (3) were scanned by quantitative computed tomography (QCT) at the hip, (4) had hip bone strength estimated by finite element modeling, or (5) had lost >10% of areal bone mineral density (aBMD) at the hip or lumbar spine as measured by dual-energy X-ray absorptiometry (DXA). Because of the limitations of DXA in describing the effects of spaceflight on bone strength, the panel recommended that the U.S. space program use QCT and finite element modeling to further study the unique effects of spaceflight (and recovery) on bone health in order to better inform clinical decisions.
Collapse
Affiliation(s)
- Eric S Orwoll
- Bone and Mineral Unit, Oregon Health and Science University, Portland, OR, USA
| | | | | | | | | | | | | | | | | | | |
Collapse
|
36
|
Roda A, Mirasoli M, Guardigli M, Simoni P, Festi D, Afonin B, Vasilyeva G. Non-invasive panel tests for gastrointestinal motility monitoring within the MARS-500 Project. World J Gastroenterol 2013; 19:2208-2216. [PMID: 23599647 PMCID: PMC3627885 DOI: 10.3748/wjg.v19.i14.2208] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/12/2012] [Revised: 01/11/2013] [Accepted: 01/24/2013] [Indexed: 02/06/2023] Open
Abstract
AIM: To develop an integrated approach for monitoring gastrointestinal motility and inflammation state suitable for application in long-term spaceflights.
METHODS: Breath tests based on the oral administration of 13C-labeled or hydrogen-producing substrates followed by the detection of their metabolites (13CO2 or H2) in breath were used to measure gastrointestinal motility parameters during the 520-d spaceflight ground simulation within the MARS-500 Project. In particular, the gastric emptying rates of solid and liquid contents were evaluated by 13C-octanoic acid and 13C-acetate breath tests, respectively, whereas the orocecal transit time was assessed by an inulin H2-breath test, which was performed simultaneously with the 13C-octanoic acid breath test. A ready-to-eat, standardized pre-packaged muffin containing 100 mg of 13C-octanoic acid was used in the 13C-octanoic acid breath test to avoid the extemporaneous preparation of solid meals. In addition, a cassette-type lateral flow immunoassay was employed to detect fecal calprotectin, a biomarker of intestinal inflammation. Because no items could be introduced into the simulator during the experiment, all materials and instrumentation required for test performance during the entire mission simulation had to be provided at the beginning of the experiment.
RESULTS: The experiments planned during the simulation of a manned flight to Mars could be successfully performed by the crewmembers without any external assistance. No evident alterations (i.e., increasing or decreasing trends) in the gastric emptying rates were detected using the 13C-breath tests during the mission simulation, as the gastric emptying half-times were in the range of those reported for healthy subjects. In contrast to the 13C-breath tests, the results of the inulin H2-breath test were difficult to interpret because of the high variability of the H2 concentration in the breath samples, even within the same subject. This variability suggested that the H2-breath test was strongly affected by external factors, which may have been related to the diet of the crewmembers or to environmental conditions (e.g., the accumulation of hydrogen in the simulator microenvironment). At least in closed microenvironments such as the MARS-500 simulator, 13C-breath tests should therefore be preferred to H2-breath tests. Finally, the fecal calprotectin test showed significant alterations during the mission simulation: all of the crewmembers were negative for the test at the beginning of the simulation but showed various degrees of positivity in at least one of the subsequent tests, thus indicating the onset of an intestinal inflammation.
CONCLUSION: Breath tests, especially those 13C-based, proved suitable for monitoring gastrointestinal motility in the 520-d isolation experiment within MARS-500 project and can be applied in long-term spaceflights.
Collapse
|
37
|
The Effect of Microgravity on Ocular Structures and Visual Function: A Review. Surv Ophthalmol 2013; 58:155-63. [DOI: 10.1016/j.survophthal.2012.04.002] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2011] [Revised: 04/08/2012] [Accepted: 04/10/2012] [Indexed: 11/17/2022]
|
38
|
Smith S, Rice B, Dlouhy H, Zwart S. Assessment of Nutritional Intake During Space Flight and Space Flight Analogs. ACTA ACUST UNITED AC 2013. [DOI: 10.1016/j.profoo.2013.04.006] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
|
39
|
Smith SM, McCoy T, Gazda D, Morgan JLL, Heer M, Zwart SR. Space flight calcium: implications for astronaut health, spacecraft operations, and Earth. Nutrients 2012; 4:2047-68. [PMID: 23250146 PMCID: PMC3546622 DOI: 10.3390/nu4122047] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2012] [Revised: 11/13/2012] [Accepted: 12/10/2012] [Indexed: 11/21/2022] Open
Abstract
The space flight environment is known to induce bone loss and, subsequently, calcium loss. The longer the mission, generally the more bone and calcium are lost. This review provides a history of bone and calcium studies related to space flight and highlights issues related to calcium excretion that the space program must consider so that urine can be recycled. It also discusses a novel technique using natural stable isotopes of calcium that will be helpful in the future to determine calcium and bone balance during space flight.
Collapse
Affiliation(s)
- Scott M. Smith
- Human Health and Performance Directorate, NASA Lyndon B. Johnson Space Center, Houston, TX 77058, USA; E-Mail:
| | - Torin McCoy
- Human Health and Performance Directorate, NASA Lyndon B. Johnson Space Center, Houston, TX 77058, USA; E-Mail:
| | - Daniel Gazda
- Wyle Science, Technology & Engineering Group, Houston, TX 77058, USA; E-Mail:
| | - Jennifer L. L. Morgan
- Oak Ridge Associated Universities/NASA Post-Doctoral Fellow, NASA Lyndon B. Johnson Space Center, Houston, TX 77058, USA; E-Mail:
| | - Martina Heer
- Profil, 41460 Neuss, Germany; E-Mail:
- University of Bonn, 53115 Bonn, Germany
| | - Sara R. Zwart
- Division of Space Life Sciences, Universities Space Research Association, Houston, TX 77058, USA; E-Mail:
| |
Collapse
|
40
|
Morgan JLL, Zwart SR, Heer M, Ploutz-Snyder R, Ericson K, Smith SM. Bone metabolism and nutritional status during 30-day head-down-tilt bed rest. J Appl Physiol (1985) 2012. [DOI: 10.115210.1152/japplphysiol.01064.2012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
Bed rest studies provide an important tool for modeling physiological changes that occur during spaceflight. Markers of bone metabolism and nutritional status were evaluated in 12 subjects (8 men, 4 women; ages 25–49 yr) who participated in a 30-day −6° head-down-tilt diet-controlled bed rest study. Blood and urine samples were collected twice before, once a week during, and twice after bed rest. Data were analyzed using a mixed-effects linear regression with a priori contrasts comparing all days to the second week of the pre-bed rest acclimation period. During bed rest, all urinary markers of bone resorption increased ∼20% ( P < 0.001), and serum parathyroid hormone decreased ∼25% ( P < 0.001). Unlike longer (>60 days) bed rest studies, neither markers of oxidative damage nor iron status indexes changed over the 30 days of bed rest. Urinary oxalate excretion decreased ∼20% during bed rest ( P < 0.001) and correlated inversely with urinary calcium ( R = −0.18, P < 0.02). These data provide a broad overview of the biochemistry associated with short-duration bed rest studies and provide an impetus for using shorter studies to save time and costs wherever possible. For some effects related to bone biochemistry, short-duration bed rest will fulfill the scientific requirements to simulate spaceflight, but other effects (antioxidants/oxidative damage, iron status) do not manifest until subjects are in bed longer, in which case longer studies or other analogs may be needed. Regardless, maximizing research funding and opportunities will be critical to enable the next steps in space exploration.
Collapse
Affiliation(s)
- Jennifer L. L. Morgan
- Oak Ridge Associated Universities/NASA Post-Doctoral Fellow, NASA Johnson Space Center, Houston, Texas
| | - Sara R. Zwart
- Universities Space Research Association and NASA, NASA Johnson Space Center, Houston, Texas
| | - Martina Heer
- Department of Nutrition and Food Science, Nutritional Physiology, University of Bonn, Bonn, Germany
- Profil Institute for Metabolic Research, Neuss, Germany
| | - Robert Ploutz-Snyder
- Universities Space Research Association and NASA, NASA Johnson Space Center, Houston, Texas
| | - Karen Ericson
- Department of Chemistry, Indiana University-Purdue University Fort Wayne, Fort Wayne, Indiana; and
| | | |
Collapse
|
41
|
Morgan JLL, Zwart SR, Heer M, Ploutz-Snyder R, Ericson K, Smith SM. Bone metabolism and nutritional status during 30-day head-down-tilt bed rest. J Appl Physiol (1985) 2012; 113:1519-29. [PMID: 22995395 PMCID: PMC3524659 DOI: 10.1152/japplphysiol.01064.2012] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2012] [Accepted: 09/18/2012] [Indexed: 11/22/2022] Open
Abstract
Bed rest studies provide an important tool for modeling physiological changes that occur during spaceflight. Markers of bone metabolism and nutritional status were evaluated in 12 subjects (8 men, 4 women; ages 25-49 yr) who participated in a 30-day -6° head-down-tilt diet-controlled bed rest study. Blood and urine samples were collected twice before, once a week during, and twice after bed rest. Data were analyzed using a mixed-effects linear regression with a priori contrasts comparing all days to the second week of the pre-bed rest acclimation period. During bed rest, all urinary markers of bone resorption increased ~20% (P < 0.001), and serum parathyroid hormone decreased ~25% (P < 0.001). Unlike longer (>60 days) bed rest studies, neither markers of oxidative damage nor iron status indexes changed over the 30 days of bed rest. Urinary oxalate excretion decreased ~20% during bed rest (P < 0.001) and correlated inversely with urinary calcium (R = -0.18, P < 0.02). These data provide a broad overview of the biochemistry associated with short-duration bed rest studies and provide an impetus for using shorter studies to save time and costs wherever possible. For some effects related to bone biochemistry, short-duration bed rest will fulfill the scientific requirements to simulate spaceflight, but other effects (antioxidants/oxidative damage, iron status) do not manifest until subjects are in bed longer, in which case longer studies or other analogs may be needed. Regardless, maximizing research funding and opportunities will be critical to enable the next steps in space exploration.
Collapse
Affiliation(s)
- Jennifer L L Morgan
- Oak Ridge Associated Universities, NASA Johnson Space Center, 2101 NASA Parkway, Houston, TX 77030, USA
| | | | | | | | | | | |
Collapse
|
42
|
Smith SM, Heer MA, Shackelford LC, Sibonga JD, Ploutz-Snyder L, Zwart SR. Benefits for bone from resistance exercise and nutrition in long-duration spaceflight: Evidence from biochemistry and densitometry. J Bone Miner Res 2012; 27:1896-906. [PMID: 22549960 DOI: 10.1002/jbmr.1647] [Citation(s) in RCA: 182] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Exercise has shown little success in mitigating bone loss from long-duration spaceflight. The first crews of the International Space Station (ISS) used the "interim resistive exercise device" (iRED), which allowed loads of up to 297 lb(f) (or 1337 N) but provided little protection of bone or no greater protection than aerobic exercise. In 2008, the Advanced Resistive Exercise Device (ARED), which allowed absolute loads of up to 600 lb(f) (1675 N), was launched to the ISS. We report dietary intake, bone densitometry, and biochemical markers in 13 crewmembers on ISS missions from 2006 to 2009. Of these 13, 8 had access to the iRED and 5 had access to the ARED. In both groups, bone-specific alkaline phosphatase tended to increase during flight toward the end of the mission (p = 0.06) and increased 30 days after landing (p < 0.001). Most markers of bone resorption were also increased in both groups during flight and 30 days after landing (p < 0.05). Bone densitometry revealed significant interactions (time and exercise device) for pelvis bone mineral density (BMD) and bone mineral content (p < 0.01), hip femoral neck BMD (p < 0.05), trochanter BMD (p < 0.05), and total hip BMD (p < 0.05). These variables were unchanged from preflight only for ARED crewmembers, who also returned from flight with higher percent lean mass and lower percent fat mass. Body mass was unchanged after flight in both groups. All crewmembers had nominal vitamin D status (75 ± 17 nmol/L) before and during flight. These data document that resistance exercise, coupled with adequate energy intake (shown by maintenance of body mass determined by dual-energy X-ray absorptiometry [DXA]) and vitamin D, can maintain bone in most regions during 4- to 6-month missions in microgravity. This is the first evidence that improving nutrition and resistance exercise during spaceflight can attenuate the expected BMD deficits previously observed after prolonged missions.
Collapse
Affiliation(s)
- Scott M Smith
- Human Adaptation and Countermeasures Division, National Aeronautics and Space Administration, Lyndon B. Johnson Space Center, 2101 NASA Parkway, Houston, TX 77058, USA.
| | | | | | | | | | | |
Collapse
|
43
|
Fitts RH, Trappe SW, Costill DL, Gallagher PM, Creer AC, Colloton PA, Peters JR, Romatowski JG, Bain JL, Riley DA. Prolonged space flight-induced alterations in the structure and function of human skeletal muscle fibres. J Physiol 2010; 588:3567-92. [PMID: 20660569 DOI: 10.1113/jphysiol.2010.188508] [Citation(s) in RCA: 218] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
The primary goal of this study was to determine the effects of prolonged space flight (180 days) on the structure and function of slow and fast fibres in human skeletal muscle. Biopsies were obtained from the gastrocnemius and soleus muscles of nine International Space Station crew members 45 days pre- and on landing day (R+0) post-flight. The main findings were that prolonged weightlessness produced substantial loss of fibre mass, force and power with the hierarchy of the effects being soleus type I > soleus type II > gastrocnemius type I > gastrocnemius type II. Structurally, the quantitatively most important adaptation was fibre atrophy, which averaged 20% in the soleus type I fibres (98 to 79 μm diameter). Atrophy was the main contributor to the loss of peak force (P(0)), which for the soleus type I fibre declined 35% from 0.86 to 0.56 mN. The percentage decrease in fibre diameter was correlated with the initial pre-flight fibre size (r = 0.87), inversely with the amount of treadmill running (r = 0.68), and was associated with an increase in thin filament density (r = 0.92). The latter correlated with reduced maximal velocity (V(0)) (r = 0.51), and is likely to have contributed to the 21 and 18% decline in V(0) in the soleus and gastrocnemius type I fibres. Peak power was depressed in all fibre types with the greatest loss (55%) in the soleus. An obvious conclusion is that the exercise countermeasures employed were incapable of providing the high intensity needed to adequately protect fibre and muscle mass, and that the crew's ability to perform strenuous exercise might be seriously compromised. Our results highlight the need to study new exercise programmes on the ISS that employ high resistance and contractions over a wide range of motion to mimic the range occurring in Earth's 1 g environment.
Collapse
Affiliation(s)
- R H Fitts
- Marquette University, Department of Biological Sciences, PO Box 1881, Milwaukee, WI 53201-1881, USA.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
44
|
Zwart SR, Crawford GE, Gillman PL, Kala G, Rodgers AS, Rogers A, Inniss AM, Rice BL, Ericson K, Coburn S, Bourbeau Y, Hudson E, Mathew G, DeKerlegand DE, Sams CF, Heer MA, Paloski WH, Smith SM. Effects of 21 days of bed rest, with or without artificial gravity, on nutritional status of humans. J Appl Physiol (1985) 2009; 107:54-62. [PMID: 19074571 PMCID: PMC4073965 DOI: 10.1152/japplphysiol.91136.2008] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2008] [Accepted: 12/01/2008] [Indexed: 11/22/2022] Open
Abstract
Spaceflight and bed rest models of microgravity have profound effects on physiological systems, including the cardiovascular, musculoskeletal, and immune systems. These effects can be exacerbated by suboptimal nutrient status, and therefore it is critical to monitor nutritional status when evaluating countermeasures to mitigate negative effects of spaceflight. As part of a larger study to investigate the usefulness of artificial gravity as a countermeasure for musculoskeletal and cardiovascular deficits during bed rest, we tested the hypothesis that artificial gravity would have an effect on some aspects of nutritional status. Dietary intake was recorded daily before, during, and after 21 days of bed rest with artificial gravity (n = 8) or bed rest alone (n = 7). We examined body composition, hematology, general blood chemistry, markers of oxidative damage, and blood levels of selected vitamins and minerals before, during, and after the bed rest period. Several indicators of vitamin status changed in response to diet changes: serum alpha- and gamma-tocopherol and urinary 4-pyridoxic acid decreased (P < 0.001) and plasma beta-carotene increased (P < 0.001) in both groups during bed rest compared with before bed rest. A decrease in hematocrit (P < 0.001) after bed rest was accompanied by a decrease in transferrin (P < 0.001), but transferrin receptors were not changed. These data provide evidence that artificial gravity itself does not negatively affect nutritional status during bed rest. Likewise, artificial gravity has no protective effect on nutritional status during bed rest.
Collapse
Affiliation(s)
- S. R. Zwart
- Universities Space Research Association, Houston; Enterprise Advisory Services, Inc., Houston; University of Texas Medical Branch, Galveston, Texas; Department of Chemistry, Indiana University-Purdue University Fort Wayne, Fort Wayne, Indiana; JES Tech, Houston; Human Adaptation and Countermeasures Division, National Aeronautics and Space Administration Johnson Space Center, Houston, Texas; and German Aerospace Center-Institute of Aerospace Medicine, Linder Hoehe, Cologne, Germany
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
45
|
Trappe S, Costill D, Gallagher P, Creer A, Peters JR, Evans H, Riley DA, Fitts RH. Exercise in space: human skeletal muscle after 6 months aboard the International Space Station. J Appl Physiol (1985) 2009; 106:1159-68. [PMID: 19150852 DOI: 10.1152/japplphysiol.91578.2008] [Citation(s) in RCA: 235] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The aim of this investigation was to document the exercise program used by crewmembers (n = 9; 45 +/- 2 yr) while aboard the International Space Station (ISS) for 6 mo and examine its effectiveness for preserving calf muscle characteristics. Before and after spaceflight, we assessed calf muscle volume (MRI), static and dynamic calf muscle performance, and muscle fiber types (gastrocnemius and soleus). While on the ISS, crewmembers had access to a running treadmill, cycle ergometer, and resistance exercise device. The exercise regimen varied among the crewmembers with aerobic exercise performed approximately 5 h/wk at a moderate intensity and resistance exercise performed 3-6 days/wk incorporating multiple lower leg exercises. Calf muscle volume decreased (P < 0.05) 13 +/- 2% with greater (P < 0.05) atrophy of the soleus (-15 +/- 2%) compared with the gastrocnemius (-10 +/- 2%). Peak power was 32% lower (P < 0.05) after spaceflight. Force-velocity characteristics were reduced (P < 0.05) -20 to -29% across the velocity spectrum. There was a 12-17% shift in myosin heavy chain (MHC) phenotype of the gastrocnemius and soleus with a decrease (P < 0.05) in MHC I fibers and a redistribution among the faster phenotypes. These data show a reduction in calf muscle mass and performance along with a slow-to-fast fiber type transition in the gastrocnemius and soleus muscles, which are all qualities associated with unloading in humans. Future long-duration space missions should modify the current ISS exercise prescription and/or hardware to better preserve human skeletal muscle mass and function, thereby reducing the risk imposed to crewmembers.
Collapse
Affiliation(s)
- Scott Trappe
- Human Performance Laboratory, Ball State University, Muncie, IN 47306, USA.
| | | | | | | | | | | | | | | |
Collapse
|