Defining the Relation Between Biomarkers of Oxidative and Inflammatory Stress and Atherosclerosis Risk in Astronauts During and After Long-duration Spaceflight (Cardio Ox) - 07.29.14
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The objective of Defining the Relationship Between Biomarkers of Oxidative and Inflammatory Stress and the Risk for Atherosclerosis in Astronauts During and After Long-duration Spaceflight (Cardio Ox) is to determine whether biological markers of oxidative and inflammatory stress are elevated during and after space flight and whether this results in an increased, long-term risk of atherosclerosis in astronauts. Twelve crewmembers will provide blood and urine samples to assess biomarkers before launch, 15 and 60 days after launch, 15 days before returning to Earth, and within days after landing. Ultrasound scans of the carotid and brachial arteries will be obtained at the same time points, as well as through 5 years after landing, as an indicator of cardiovascular health.
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OpNom Cardio Ox
Johnson Space Center, Human Research Program, Houston, TX, United States
Sponsoring Space Agency
National Aeronautics and Space Administration (NASA)
Human Exploration and Operations Mission Directorate (HEOMD)
Scientific Discovery, Earth Benefits, Space Exploration
ISS Expedition Duration
September 2013 - Ongoing
Previous ISS Missions
Future human space travel will primarily consist of long duration missions onboard the International Space Station or exploration class missions to Mars, its moons, or nearby asteroids. These types of missions may increase the risk of increased oxidative damage and inflammation primarily from radiation, but also from psychological stress, reduced physical activity, diminished nutritional standards and, in the case of extravehicular activity, increased oxygen exposure. There is evidence that increased oxidative damage and inflammation can accelerate the development of atherosclerosis. This study will inform Space Medicine about the potential long-term effects of space flight (5 years post-landing) on cardiovascular health.
The investigation intends to provide a greater understanding of space-related cardiovascular disease risk, specifically to identify and validate markers and indices of increased cardiovascular health risk during and after long-duration spaceflight.
- The experiment is designed to determine whether markers of oxidative stress and inflammation in the blood and urine are elevated in astronauts participating in long-duration space flight and whether there are concomitant changes in arterial structure and function. Specifically, this study seeks to clarify the previously conflicting observations regarding oxidative stress and inflammation during and after space flight and relate these to long-term changes in vascular structure and function which might predict future development of atherosclerosis in astronauts.
Future human space travel will primarily consist of long duration missions onboard the International Space Station or exploration class missions to Mars, its moons, or nearby asteroids. These types of missions may increase the risk of oxidative and inflammatory damage primarily from radiation, but also from psychological stress, reduced physical activity, diminished nutritional standards and, in the case of extravehicular activity, hyperoxic/hypoxic exposure. There is evidence that increased oxidative damage and inflammation can accelerate the development of atherosclerosis. The purpose of this study is to identify biomarkers of oxidative stress and inflammation before, during, and after long duration spaceflight and to relate them to indices of atherosclerosis risk. The investigators will measure a number of blood and urine biomarkers, some of which we have previously shown to be elevated with spaceflight. Furthermore, they will track arterial structure and function via ultrasound measures of carotid intima-medial thickness and brachial artery flow-mediated dilation. Carotid intima-medial thickness has been shown to be a better indicator than Framingham Risk scores for prediction of atherosclerosis. Brachial flow-mediated dilation is a good index of endothelium-dependent vasodilation, which is a sensitive predictor of atherosclerotic risk. The investigators hypothesize that these biomarkers of oxidative and inflammatory stress will be increased with spaceflight and will correlate with decreased flow-mediated dilation and increased carotid intima-medial thickness. Furthermore, they hypothesize that measures of oxidative stress will return to baseline after flight, but that biomarkers of inflammatory stress and vascular indices of atherosclerosis risk will remain elevated. This is the first study to propose assessing atherosclerotic risk using biochemical, structural and functional measures during, immediately after, and for up to five years after landing.
Cardio Ox will determine whether biological markers of oxidative and inflammatory stress are elevated during and after space flight, and how those markers correlate with the long-term health changes in astronauts. This will help in defining the cardiovascular health risks associated with long duration space flight and in developing countermeasures, as well as understanding crew health care needs in the years after their return to Earth.
This prospective study of a healthy population exposed to environmental conditions that are expected to result in elevated levels of oxidative and inflammatory stress will improve the overall understanding regarding the factors involved in, and progression of, cardiovascular disease.
A total of twelve subjects are required for this investigation. In-flight sessions are planned on flight day 15 (FD15), FD60 and FD180/R-15 for a mission duration of six months and FD15, 60, 180, 240, 300, and R-15 for a mission duration of one year. Each session includes an ultrasound scan, blood sampling, and a 24-hour urine collection. The blood sample is collected within 24 hours of the start of urine collection and scans are performed within 3 days of the blood collection. Scheduling tolerance for the FD15 session is ±5 days; all other sessions are ±7 days. Subjects will perform self-scans using Remote Guidance, therefore, real-time video downlink is required. Blood and urine samples are returned to Earth for analysis, ideally within a year of the sampling date.
Inflight ultrasound scans using the HRF Ultrasound 2 are performed on FD15, 60 and 180/R-15 (FD15, 60, 180, 240, 300, and R-15 for a mission duration of one year) via real-time Remote Guidance. Each scan is preceded or followed by blood and 24-hour urine sample collections. The blood samples are processed in the refrigerated centrifuge and then stored in the MELFI. Urine is collected void by void for 24 hours and syringe aliquot samples are stored in the MELFI.
Human Adaptation and Countermeasures Division:
Human Adaptation and Countermeasures Division: