Article

Effects of microgravity and hypergravity on platelet functions

Department of Biological Science and Technology, Beijing University of Aeronautics and Astronautics, 37 Xueyuan Road, Haidian district, Beijing 100083, China.
Thrombosis and Haemostasis (Impact Factor: 5.76). 06/2009; 101(5):902-10. DOI: 10.1160/TH08-11-0750
Source: PubMed

ABSTRACT Many serious thrombotic and haemorrhagic diseases or fatalities have been documented in human being exposed to microgravity or hypergravity environments, such as crewmen in space, roller coaster riders, and aircrew subjected to high-G training. Some possible related organs have been examined to explore the mechanisms underlying these gravity change-related diseases. However, the role of platelets which are the primary players in both thrombosis and haemostasis is unknown. Here we show that platelet aggregation induced by ristocetin or collagen and platelet adhesion to von Willebrand factor (VWF) were significantly decreased after platelets were exposed to simulated microgravity. Conversely, these platelet functions were increased after platelets were exposed to hypergravity. The tail bleeding time in vivo was significantly shortened in mice exposed to high-G force, whereas, was prolonged in hindlimb unloaded mice. Furthermore, three of 23 mice died after 15 minutes of -8 Gx stress. Platelet thrombi disseminated in the heart ventricle and blood vessels in the brain, lung, and heart from the dead mice. Finally, glycoprotein (GP) Ibalpha surface expression and its association with the cytoskeleton were significantly decreased in platelets exposed to simulated microgravity, and obviously increased in hypergravity-exposed platelets. These data indicate that the platelet functions are inhibited in microgravity environments, and activated under high-G conditions, suggesting a novel mechanism for gravity change-related haemorrhagic and thrombotic diseases. This mechanism has important implications for preventing and treating gravity change-related diseases, and also suggests that special attentions should be paid to human actions under different gravity conditions.

0 Bookmarks
 · 
170 Views
  • [Show abstract] [Hide abstract]
    ABSTRACT: Maintaining a good health requires the maintenance of a body homeostasis which largely depends on correct functioning of thyroid gland. The cells of the thyroid tissue are strongly sensitive to hypogravity, as already proven in mice after returning to the earth from long-term space missions. Here we studied whether hypergravity may be used to counteract the physiological deconditioning of long-duration spaceflight. We investigated the influence of hypergravity on key lipids and proteins involved in thyroid tissue function. We quantified cholesterol (CHO) and different species of sphingomyelin (SM) and ceramide, analysed thyrotropin (TSH) related molecules such as thyrotropin-receptor (TSHR), cAMP, Caveolin-1 and molecule signalling such as Signal transducer and activator of transcription-3 (STAT3). The hypergravity treatment resulted in the upregulation of the TSHR and Caveolin-1 and downregulation of STAT3 without changes of cAMP. TSHR lost its specific localization and spread throughout the cell membrane; TSH treatment facilitated the shedding of α subunit of TSHR and its releasing into the extracellular space. No specific variations were observed for each species of SM and ceramide. Importantly, the level of CHO was strongly reduced. In conclusion, hypergravity conditions induce change in CHO and TSHR of thyroid gland. The possibility that lipid rafts are strongly perturbed by hypergravity-induced CHO depletion by influencing TSH-TSHR interaction was discussed.
    PLoS ONE 05/2014; 9(5):e98250. DOI:10.1371/journal.pone.0098250 · 3.53 Impact Factor
    This article is viewable in ResearchGate's enriched format
  • [Show abstract] [Hide abstract]
    ABSTRACT: Gravity supports all the life activities present on earth. Microgravity environments have effect on the biological functions and physiological status of an individual. The present study was undertaken to investigate the effect of simulated microgravity on important regulatory enzymes of carbohydrate metabolism in liver using HLS mice model. Following hind limb unloading of mice for 11 days the animal’s average body weights were found to be not different, while the liver weights were decreased and found to be significantly different (p p p p Keywords: Hexokinase; LDH; PEPCK; PFK-2; Simulated microgravity Document Type: Research Article DOI: http://dx.doi.org/10.1007/s12217-013-9356-7 Affiliations: 1: Department of Biology, Texas Southern University, Houston, TX, 77004, USA 2: Department of Biology, Texas Southern University, Houston, TX, 77004, USA, Email: sharma@bub.ernet.in Publication date: February 1, 2014 $(document).ready(function() { var shortdescription = $(".originaldescription").text().replace(/\\&/g, '&').replace(/\\, '<').replace(/\\>/g, '>').replace(/\\t/g, ' ').replace(/\\n/g, ''); if (shortdescription.length > 350){ shortdescription = "" + shortdescription.substring(0,250) + "... more"; } $(".descriptionitem").prepend(shortdescription); $(".shortdescription a").click(function() { $(".shortdescription").hide(); $(".originaldescription").slideDown(); return false; }); }); Related content In this: publication By this: publisher By this author: Ramirez, Joaquin ; Periyakaruppan, Adaikkappan ; Sarkar, Shubhashish ; Ramesh, Govindarajan ; Sharma, S. GA_googleFillSlot("Horizontal_banner_bottom");
    Microgravity - Science and Technology 02/2014; 25(5). DOI:10.1007/s12217-013-9356-7 · 0.65 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Abstract Rubenstein, David A, and Wei Yin. Hypergravity and hypobaric hypoxic conditions promote endothelial cell and platelet activation. High Alt Med Biol. 15:000-000, 2014.-Cardiovascular disease risk is heightened during exposure to altered gravity and/or altered barometric conditions. Previous work has suggested that this heightened cardiovascular risk is due to enhancements of endothelial cell inflammatory and/or thrombogenic responses. In recent work, the role of platelets on instigating or inhibiting endothelial cell responses associated with cardiovascular disease has been found to be dependent on both biochemical and biophysical factors. In this work, we aimed to determine how two biophysical forces, gravity and atmospheric pressure, alter endothelial cell and platelet functions and their interactions to instigate or inhibit cardiovascular disease responses. To address this aim, endothelial cells and platelets were subjected to a force 8 times greater than the normal gravitational force, for up to 30 minutes. In separate experiments, endothelial cells and platelets were subjected to 50% of normal atmospheric pressure. Endothelial cell and platelet responses, associated with cardiovascular diseases, were measured as a time course during exposure. In general, the exposure of endothelial cells to either hypergravity or hypobaric conditions enhanced cardiovascular disease responses. However, the presence of platelets generally inhibited endothelial cell responses. Platelet activation was, however, somewhat enhanced under both hypergravity and hypobaric conditions. Our data suggest that altered biophysical forces can modulate endothelial cell and platelet responses that are salient for cardiovascular disease progression. However, the interaction of these two cells tends to restrain the progression of the pro-cardiovascular disease responses.
    High Altitude Medicine & Biology 09/2014; 15(3). DOI:10.1089/ham.2013.1139 · 1.82 Impact Factor

Preview

Download
1 Download
Available from