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Moussa MS, Goldsmith M, Komarova SV. Craniofacial Bones and Teeth in Spacefarers: Systematic Review and Meta-analysis. JDR Clin Trans Res 2023; 8:113-122. [PMID: 35311413 PMCID: PMC10026165 DOI: 10.1177/23800844221084985] [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: 11/15/2022] Open
Abstract
INTRODUCTION Estimating the risk of dental problems in long-duration space missions to the Moon and Mars is critical for avoiding dental emergencies in an environment that does not support proper treatment. Previous risk estimates were constructed based on the experience in short-duration space missions and isolated environments on Earth. However, previous estimates did not account for potential changes in dental structures due to space travel, even though bone loss is a known problem for long-duration spaceflights. The objective of this study was to systematically analyze the changes in hard tissues of the craniofacial complex during spaceflights. METHODS Comprehensive search of Medline, Embase, Scopus, the NASA Technical Report Server, and other sources identified 1,585 potentially relevant studies. After screening, 32 articles that presented quantitative data for skull in humans (6/32) and for calvariae, mandible, and lower incisors in rats (20/32) and mice (6/32) were selected. RESULTS Skull bone mineral density showed a significant increase in spacefaring humans. In spacefaring rodents, calvariae bone volume to tissue volume (BV/TV) demonstrated a trend toward increasing that did not reach statistical significance, while in mandibles, there was a significant decrease in BV/TV. Dentin thickness and incisor volume of rodent incisors were not significantly different between spaceflight and ground controls. DISCUSSION Our study demonstrates significant knowledge gaps regarding many structures of the craniofacial complex such as the maxilla, molar, premolar, and canine teeth, as well as small sample sizes for the studies of mandible and incisors. Understanding the effects of microgravity on craniofacial structures is important for estimating risks during long-duration spaceflight and for formulating proper protocols to prevent dental emergencies. KNOWLEDGE TRANSFER STATEMENT Avoiding dental emergencies in long-duration spaceflights is critical since this environment does not support proper treatment. Prior risk estimates did not account for changes in dental structures due to space travel. We reviewed and synthesized the literature for changes in craniofacial complex associated with spaceflight. The results of our study will help clinicians and scientists to better prepare to mitigate potential oral health issues in space travelers on long-duration missions.
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Affiliation(s)
- M S Moussa
- Faculty of Dental Medicine and Oral Health Sciences, McGill University, Montreal, Quebec, Canada
- Shriners Hospital for Children-Canada, Montreal, Quebec, Canada
| | - M Goldsmith
- Faculty of Dental Medicine and Oral Health Sciences, McGill University, Montreal, Quebec, Canada
- Shriners Hospital for Children-Canada, Montreal, Quebec, Canada
| | - S V Komarova
- Faculty of Dental Medicine and Oral Health Sciences, McGill University, Montreal, Quebec, Canada
- Shriners Hospital for Children-Canada, Montreal, Quebec, Canada
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Sun H, Zhou Q, Qiao P, Zhu D, Xin B, Wu B, Tang C. Short-term head-down bed rest microgravity simulation alters salivary microbiome in young healthy men. Front Microbiol 2022; 13:1056637. [PMID: 36439790 PMCID: PMC9684331 DOI: 10.3389/fmicb.2022.1056637] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Accepted: 10/27/2022] [Indexed: 01/03/2024] Open
Abstract
Microgravity influences are prevalent during orbital flight and can adversely affect astronaut physiology. Notably, it may affect the physicochemical properties of saliva and the salivary microbial community. Therefore, this study simulates microgravity in space using a ground-based -6° head-down bed rest (HDBR) test to observe the effects of microgravity on oral salivary secretion function and the salivary microbiome. Sixteen healthy young male volunteers were recruited for the 15-day -6° HDBR test. Non-stimulated whole saliva was collected on day 1 (pre-HDBR), on days 5, 10, and 15 of HDBR, and day 6 of recovery. Salivary pH and salivary flow rate were measured, and the V3-V4 region of the 16S rRNA gene was sequenced and analyzed in 80 saliva samples. The results showed that there were no significant differences in salivary pH, salivary flow rate, and alpha diversity between any two time points. However, beta diversity analysis revealed significant differences between pre-HDBR and the other four time points. After HDBR, the relative abundances of Actinomyces, Parvimonas, Peptostreptococcus, Porphyromonas, Oribacterium, and Capnocytophaga increased significantly, whereas the relative abundances of Neisseria and Haemophilus decreased significantly. However, the relative abundances of Oribacterium and Capnocytophaga did not recover to the pre-HDBR level on day 6 of recovery. Network analysis revealed that the number of relationships between genera decreased, and the positive and negative correlations between genera changed in a complex manner after HDBR and did not reach their original levels on day 6 of recovery. PICRUSt analysis demonstrated that some gene functions of the salivary microbiome also changed after HDBR and remained significantly different from those before HDBR on day 6 of recovery. Collectively, 15 days of -6° HDBR had minimal effect on salivary secretion function but resulted in significant changes in the salivary microbiome, mainly manifested as an increase in oral disease-related bacteria and a decrease in oral health-related commensal bacteria. Further research is required to confirm these oral microbial changes and explore the underlying pathological mechanisms to determine the long-term effects on astronauts embarking on long-duration voyages to outer space.
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Affiliation(s)
- Hui Sun
- 306th Clinical College of PLA, The Fifth Clinical College, Anhui Medical University, Beijing, China
- Department of Stomatology, PLA Strategic Support Force Characteristic Medical Center, Beijing, China
| | - Qian Zhou
- 306th Clinical College of PLA, The Fifth Clinical College, Anhui Medical University, Beijing, China
- Department of Stomatology, PLA Strategic Support Force Characteristic Medical Center, Beijing, China
| | - Pengyan Qiao
- Department of Stomatology, PLA Strategic Support Force Characteristic Medical Center, Beijing, China
| | - Di Zhu
- 306th Clinical College of PLA, The Fifth Clinical College, Anhui Medical University, Beijing, China
- Department of Stomatology, PLA Strategic Support Force Characteristic Medical Center, Beijing, China
| | - Bingmu Xin
- Engineering Research Center of Human Circadian Rhythm and Sleep (Shenzhen), Space Science and Technology Institute (Shenzhen), Shenzhen, China
| | - Bin Wu
- China Astronaut Research and Training Center, Beijing, China
| | - Chuhua Tang
- 306th Clinical College of PLA, The Fifth Clinical College, Anhui Medical University, Beijing, China
- Department of Stomatology, PLA Strategic Support Force Characteristic Medical Center, Beijing, China
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Roberts WE, Mangum JE, Schneider PM. Pathophysiology of Demineralization, Part I: Attrition, Erosion, Abfraction, and Noncarious Cervical Lesions. Curr Osteoporos Rep 2022; 20:90-105. [PMID: 35129809 PMCID: PMC8930910 DOI: 10.1007/s11914-022-00722-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 12/15/2021] [Indexed: 12/14/2022]
Abstract
PURPOSE OF THE REVIEW Compare pathophysiology for infectious and noninfectious demineralization disease relative to mineral maintenance, physiologic fluoride levels, and mechanical degradation. RECENT FINDINGS Environmental acidity, biomechanics, and intercrystalline percolation of endemic fluoride regulate resistance to demineralization relative to osteopenia, noncarious cervical lesions, and dental caries. Demineralization is the most prevalent chronic disease in the world: osteoporosis (OP) >10%, dental caries ~100%. OP is severely debilitating while caries is potentially fatal. Mineralized tissues have a common physiology: cell-mediated apposition, protein matrix, fluid logistics (blood, saliva), intercrystalline ion percolation, cyclic demineralization/remineralization, and acid-based degradation (microbes, clastic cells). Etiology of demineralization involves fluid percolation, metabolism, homeostasis, biomechanics, mechanical wear (attrition or abrasion), and biofilm-related infections. Bone mineral density measurement assesses skeletal mass. Attrition, abrasion, erosion, and abfraction are diagnosed visually, but invisible subsurface caries <400μm cannot be detected. Controlling demineralization at all levels is an important horizon for cost-effective wellness worldwide.
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Affiliation(s)
- W. Eugene Roberts
- grid.257413.60000 0001 2287 3919Indiana University & Purdue University at Indianapolis, 8260 Skipjack Drive, Indianapolis, IN 46236 USA
| | - Jonathan E. Mangum
- grid.1008.90000 0001 2179 088XDepartment of Biochemistry and Pharmacology, Dentistry and Health Sciences, University of Melbourne, Corner Grattan Street and Royal Parade, Parkville, Victoria 3010 Australia
| | - Paul M. Schneider
- grid.1008.90000 0001 2179 088XMelbourne Dental School, University of Melbourne, 720 Swanston St, Melbourne, Victoria 3010 Australia
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Abstract
PURPOSE OF REVIEW Osteocytes are considered to be the cells responsible for mastering the remodeling process that follows the exposure to unloading conditions. Given the invasiveness of bone biopsies in humans, both rodents and in vitro culture systems are largely adopted as models for studies in space missions or in simulated microgravity conditions models on Earth. RECENT FINDINGS After a brief recall of the main changes in bone mass and osteoclastic and osteoblastic activities in space-related models, this review focuses on the potential role of osteocytes in directing these changes. The role of the best-known signalling molecules is questioned, in particular in relation to osteocyte apoptosis. The mechanotransduction actors identified in spatial conditions and the problems related to fluid flow and shear stress changes, probably enhanced by the alteration in fluid flow and lack of convection during spaceflight, are recalled and discussed.
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Affiliation(s)
- Donata Iandolo
- U1059 INSERM - SAINBIOSE (SAnté INgéniérie BIOlogie St-Etienne) Campus Santé Innovation, Université Jean Monnet, Saint-Priest-en-Jarez, France
| | - Maura Strigini
- U1059 INSERM - SAINBIOSE (SAnté INgéniérie BIOlogie St-Etienne) Campus Santé Innovation, Université Jean Monnet, Saint-Priest-en-Jarez, France
| | - Alain Guignandon
- U1059 INSERM - SAINBIOSE (SAnté INgéniérie BIOlogie St-Etienne) Campus Santé Innovation, Université Jean Monnet, Saint-Priest-en-Jarez, France
| | - Laurence Vico
- U1059 INSERM - SAINBIOSE (SAnté INgéniérie BIOlogie St-Etienne) Campus Santé Innovation, Université Jean Monnet, Saint-Priest-en-Jarez, France.
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Moosavi D, Wolovsky D, Depompeis A, Uher D, Lennington D, Bodden R, Garber CE. The effects of spaceflight microgravity on the musculoskeletal system of humans and animals, with an emphasis on exercise as a countermeasure: a systematic scoping review. Physiol Res 2021; 70:119-151. [PMID: 33992043 DOI: 10.33549/physiolres.934550] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
The purpose of this systematic review is twofold: 1) to identify, evaluate, and synthesize the heretofore disparate scientific literatures regarding the effects of direct exposure to microgravity on the musculoskeletal system, taking into account for the first time both bone and muscle systems of both humans and animals; and 2) to investigate the efficacy and limitations of exercise countermeasures on the musculoskeletal system under microgravity in humans.The Framework for Scoping Studies (Arksey and O'Malley 2005) and the Cochrane Handbook for Systematic Reviews of Interventions (Higgins JPT 2011) were used to guide this review. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist was utilized in obtaining the combined results (Moher, Liberati et al. 2009). Data sources, PubMed, Embase, Scopus, and Web of Science were searched for published articles through October 2019 using the Mesh terms of microgravity, musculoskeletal system, and exercise countermeasures. A total of 84 references were selected, including 40 animal studies and 44 studies with human participants. The heterogeneity in the study designs, methodologies, and outcomes deemed this review unsuitable for a meta-analysis. Thus, we present a narrative synthesis of the results for the key domains under five categories: 1) Skeletal muscle responses to microgravity in humans 2) Skeletal muscle responses to microgravity in animals 3) Adaptation of the skeletal system to microgravity in humans 4) Adaptation of the skeletal system to microgravity in animals 5) Effectiveness of exercise countermeasures on the human musculoskeletal system in microgravity. Existing studies have produced only limited data on the combined effects on bone and muscle of human spaceflight, despite the likelihood that the effects on these two systems are complicated due to the components of the musculoskeletal system being anatomically and functionally interconnected. Bone is directly affected by muscle atrophy as well as by changes in muscle strength, notably at muscle attachments. Given this interplay, the most effective exercise countermeasure is likely to be robust, individualized, resistive exercise, primarily targeting muscle mass and strength.
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Affiliation(s)
- D Moosavi
- Department of Biobehavioral Sciences, Teachers College, Columbia University. New York City, NY, United States.
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Deymier AC, Schwartz AG, Lim C, Wingender B, Kotiya A, Shen H, Silva MJ, Thomopoulos S. Multiscale effects of spaceflight on murine tendon and bone. Bone 2020; 131:115152. [PMID: 31730829 PMCID: PMC7138367 DOI: 10.1016/j.bone.2019.115152] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Revised: 11/07/2019] [Accepted: 11/09/2019] [Indexed: 12/22/2022]
Abstract
Despite a wealth of data on the effects of spaceflight on tendons and bones, little is known about its effects on the interfacial tissue between these two structures, the enthesis. Mice were sent to space on three separate missions: STS-131, STS-135, and Bion-M1 to determine how spaceflight affects the composition, structure, mechanics, and gene expression of the humerus-supraspinatus and calcaneus-Achilles entheses. At the nanoscale, spaceflight resulted in decreased carbonate levels in the bone, likely due to increased remodeling, as suggested by increased expression of genes related to osteoclastogenesis (CatK, Tnfsf11) and mature osteoblasts (Col1, Osc). Tendons showed a shift in collagen fibril size towards smaller diameters that may have resulted from increased expression of genes related to collagen degradation (Mmp3, Mmp13). These nanoscale changes did not result in micro- and milliscale changes to the structure and mechanics of the enthesis. There were no changes in bone volume, trabecular structure, failure load, or stiffness with spaceflight. This lack of tissue-level change may be anatomy based, as extremities may be less sensitive to spaceflight than central locations such as vertebrae, yet results highlight that the tendon enthesis may be robust against negative effects of spaceflight.
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Affiliation(s)
- Alix C Deymier
- Department of Biomedical Engineering, University of Connecticut, Farmington, CT, United States of America.
| | - Andrea G Schwartz
- Department of Orthopaedic Surgery, Washington University, St. Louis, MO, United States of America
| | - Chanteak Lim
- Department of Orthopaedic Surgery, Washington University, St. Louis, MO, United States of America
| | - Brian Wingender
- Department of Biomedical Engineering, University of Connecticut, Farmington, CT, United States of America
| | - Akhilesh Kotiya
- Department of Orthopaedic Surgery, Washington University, St. Louis, MO, United States of America
| | - Hua Shen
- Department of Orthopaedic Surgery, Washington University, St. Louis, MO, United States of America
| | - Matthew J Silva
- Department of Orthopaedic Surgery, Washington University, St. Louis, MO, United States of America
| | - Stavros Thomopoulos
- Department of Orthopedic Surgery, Columbia University, New York, NY, United States of America; Department of Biomedical Engineering, Columbia University, New York, NY, United States of America.
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Hand AR, Dagdeviren D, Larson NA, Haxhi C, Mednieks MI. Effects of spaceflight on the mouse submandibular gland. Arch Oral Biol 2019; 110:104621. [PMID: 31805482 DOI: 10.1016/j.archoralbio.2019.104621] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Revised: 10/27/2019] [Accepted: 11/18/2019] [Indexed: 02/02/2023]
Abstract
OBJECTIVE This study was conducted to determine if the morphology and biochemistry of the mouse submandibular gland is affected by microgravity and the spaceflight environment. DESIGN Tissues from female mice flown on the US space shuttle missions Space Transportation System (STS)-131 and STS-135 for 15 and 13 d, respectively, and from male mice flown on the 30 d Russian Bion-M1 biosatellite, were examined using transmission electron microscopy and light and electron microscopic immunohistochemistry. RESULTS In contrast to the parotid gland, morphologic changes were not apparent in the submandibular gland. No significant changes in protein expression, as assessed by quantitative immunogold labeling, occurred in female mice flown for 13-15 d. In male mice, however, increased labeling for salivary androgen binding protein alpha (in acinar cell secretory granules), and epidermal growth factor and nerve growth factor (in granular convoluted duct cell granules) was seen after 30 d in space. CONCLUSION These results indicate that spaceflight alters secretory protein expression in the submandibular gland and suggest that the sex of the animals and the length of the flight may affect the response. These findings also show that individual salivary glands respond differently to spaceflight. Saliva contains proteins secreted from salivary glands and is easily collected, therefore is a useful biofluid for general medical analyses and in particular for monitoring the physiology and health of astronauts.
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Affiliation(s)
- Arthur R Hand
- Department of Craniofacial Sciences, School of Dental Medicine, University of Connecticut, Farmington, CT, USA.
| | - Didem Dagdeviren
- Department of Oral Health and Diagnostic Sciences, School of Dental Medicine, University of Connecticut, Farmington, CT, USA
| | - Natasha A Larson
- Department of Craniofacial Sciences, School of Dental Medicine, University of Connecticut, Farmington, CT, USA
| | - Christopher Haxhi
- Department of Craniofacial Sciences, School of Dental Medicine, University of Connecticut, Farmington, CT, USA
| | - Maija I Mednieks
- Department of Oral Health and Diagnostic Sciences, School of Dental Medicine, University of Connecticut, Farmington, CT, USA
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Maupin KA, Childress P, Brinker A, Khan F, Abeysekera I, Aguilar IN, Olivos DJ, Adam G, Savaglio MK, Ganesh V, Gorden R, Mannfeld R, Beckner E, Horan DJ, Robling AG, Chakraborty N, Gautam A, Hammamieh R, Kacena MA. Skeletal adaptations in young male mice after 4 weeks aboard the International Space Station. NPJ Microgravity 2019; 5:21. [PMID: 31583271 PMCID: PMC6760218 DOI: 10.1038/s41526-019-0081-4] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Accepted: 08/22/2019] [Indexed: 02/02/2023] Open
Abstract
Gravity has an important role in both the development and maintenance of bone mass. This is most evident in the rapid and intense bone loss observed in both humans and animals exposed to extended periods of microgravity in spaceflight. Here, cohabitating 9-week-old male C57BL/6 mice resided in spaceflight for ~4 weeks. A skeletal survey of these mice was compared to both habitat matched ground controls to determine the effects of microgravity and baseline samples in order to determine the effects of skeletal maturation on the resulting phenotype. We hypothesized that weight-bearing bones would experience an accelerated loss of bone mass compared to non-weight-bearing bones, and that spaceflight would also inhibit skeletal maturation in male mice. As expected, spaceflight had major negative effects on trabecular bone mass of the following weight-bearing bones: femur, tibia, and vertebrae. Interestingly, as opposed to the bone loss traditionally characterized for most weight-bearing skeletal compartments, the effects of spaceflight on the ribs and sternum resembled a failure to accumulate bone mass. Our study further adds to the insight that gravity has site-specific influences on the skeleton.
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Affiliation(s)
- Kevin A Maupin
- 1Department of Orthopaedic Surgery, Indiana University School of Medicine, Indianapolis, IN USA
| | - Paul Childress
- 1Department of Orthopaedic Surgery, Indiana University School of Medicine, Indianapolis, IN USA.,2Richard L. Roudebush VA Medical Center, Indianapolis, IN USA
| | - Alexander Brinker
- 1Department of Orthopaedic Surgery, Indiana University School of Medicine, Indianapolis, IN USA
| | - Faisal Khan
- 1Department of Orthopaedic Surgery, Indiana University School of Medicine, Indianapolis, IN USA
| | - Irushi Abeysekera
- 1Department of Orthopaedic Surgery, Indiana University School of Medicine, Indianapolis, IN USA
| | - Izath Nizeet Aguilar
- 1Department of Orthopaedic Surgery, Indiana University School of Medicine, Indianapolis, IN USA
| | - David J Olivos
- 1Department of Orthopaedic Surgery, Indiana University School of Medicine, Indianapolis, IN USA.,3Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN USA.,4Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, IN USA
| | - Gremah Adam
- 1Department of Orthopaedic Surgery, Indiana University School of Medicine, Indianapolis, IN USA
| | - Michael K Savaglio
- 1Department of Orthopaedic Surgery, Indiana University School of Medicine, Indianapolis, IN USA
| | - Venkateswaran Ganesh
- 1Department of Orthopaedic Surgery, Indiana University School of Medicine, Indianapolis, IN USA
| | - Riley Gorden
- 1Department of Orthopaedic Surgery, Indiana University School of Medicine, Indianapolis, IN USA
| | - Rachel Mannfeld
- 1Department of Orthopaedic Surgery, Indiana University School of Medicine, Indianapolis, IN USA
| | - Elliott Beckner
- 1Department of Orthopaedic Surgery, Indiana University School of Medicine, Indianapolis, IN USA
| | - Daniel J Horan
- 2Richard L. Roudebush VA Medical Center, Indianapolis, IN USA.,5Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, IN USA
| | - Alexander G Robling
- 2Richard L. Roudebush VA Medical Center, Indianapolis, IN USA.,5Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, IN USA
| | - Nabarun Chakraborty
- 6U.S. Army Center for Environmental Health Research, Fort Detrick, MD USA.,7Geneva Foundation, Fort Detrick, MD USA
| | | | | | - Melissa A Kacena
- 1Department of Orthopaedic Surgery, Indiana University School of Medicine, Indianapolis, IN USA.,2Richard L. Roudebush VA Medical Center, Indianapolis, IN USA.,5Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, IN USA
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Dagdeviren D, Beallias J, Khan I, Mednieks MI, Hand AR. Response of the mouse sublingual gland to spaceflight. Eur J Oral Sci 2018; 126:373-381. [PMID: 29984852 DOI: 10.1111/eos.12541] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/16/2018] [Indexed: 01/06/2023]
Abstract
The ultrastructure and immunohistochemistry of secretory proteins of sublingual glands were studied in mice flown on the US space shuttles Discovery [Space Transportation System (STS)-131] and Atlantis (STS-135). No differences in mucous acinar or serous demilune cell structure were observed between sublingual glands of ground (control) and flight mice. In contrast, previous studies showed autophagy and apoptosis of parotid serous acinar cells in flight mice. The expression of parotid secretory protein (PSP) in sublingual demilune cells of STS-131 flight mice was significantly increased compared with ground (control) mice but decreased in STS-135 flight mice. Similarly, expression of mucin (MUC-19) in acinar cells and expression of the type II regulatory subunit of protein kinase A (PKA-RII) in demilune cells were increased in STS-131 flight mice and decreased in STS-135 flight mice, but not significantly. Demilune cell and parotid protein (DCPP) was slightly decreased in mice from both flights, and nuclear PKA-RII was slightly increased. These results indicate that the response of salivary glands to spaceflight conditions varies among the different glands, cell types, and secretory proteins. Additionally, the spaceflight environment, including the effects of microgravity, modifies protein expression. Determining changes in salivary proteins may lead to development of non-invasive methods to assess the physiological status of astronauts.
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Affiliation(s)
- Didem Dagdeviren
- Division of Oral and Maxillofacial Radiology, School of Dental Medicine, University of Connecticut, Farmington, CT, USA
| | - John Beallias
- Department of Craniofacial Sciences, School of Dental Medicine, University of Connecticut, Farmington, CT, USA
| | - Izaz Khan
- Department of Craniofacial Sciences, School of Dental Medicine, University of Connecticut, Farmington, CT, USA
| | - Maija I Mednieks
- Department of Oral Health and Diagnostic Sciences, School of Dental Medicine, University of Connecticut, Farmington, CT, USA
| | - Arthur R Hand
- Department of Craniofacial Sciences, School of Dental Medicine, University of Connecticut, Farmington, CT, USA
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