The red blood cells carry oxygen throughout the body. Decreased red blood cells, called anemia, may result in physical limitations such as weakness or fatigue and cognitive slowing. On Earth, longstanding anemia is linked to lower quality of life and early mortality. White blood cells defend against infections, among many other functions. Malfunctioning white blood cells may predispose to severe infections and increase sensitivity to radiation.
This investigation will study, for the first time, the accumulation of bone marrow fat after a human subject has lived in microgravity and its impact on red and white blood cells. Using magnetic resonance imaging, blood samples, breath samples and possibly stool samples, bone marrow fat and blood survival and function will be measured. The expectation is that by imaging the marrow of specific bones in astronauts before and after flight, the impact of fat accumulation on blood elements in microgravity will be demonstrated. These results will complement previous results in space analogues; the long term bed rest studies performed in women (WISE 2005) and in men (BBR2-2). Results will also be applicable to people on Earth with decreased mobility or bedridden.
The specific objectives of this investigation are:
1: To measure fat accumulation in the bone marrow on astronauts pre- and post- stay aboard the International Space Station (ISS) using non-invasive magnetic resonance imaging (MRI).
2: To measure the effects of prospective marrow fat accumulation and microgravity on red and white blood cells using markers of erythrocyte degradation in blood, breath (CO) and stool (microbiome), as well as leukocyte function (transcriptome).
3: To analyze the effect of a) individual space flights, and b) cumulative exposure to microgravity on astronauts’ blood cell counts.
Preflight baseline data collection (BDC) is planned to occur between Launch – 90 days (L-90) and L-60. On awakening, the subject will collect ambient and alveolar breath samples into separate canisters for later analysis. Fasting blood samples will be taken. One of the samples will be treated according to a special protocol to include mixing, centrifugation, and freezing. A transcriptome blood sample may also be taken. Intestinal microbiota will be collected via a stool sample. Finally, the subject will undergo an MRI.
Postflight sample collection is similar to preflight. However, there are more collections. Breath samples will be collected on Return to earth + 3-7 days (R+3-7), R+12-15, and R+365 ±30. Blood samples will be taken on R+30 ±7, R+180 ±30, and R+365 ±30. As before, one sample will be handled per the special protocol. Leukocyte transcriptome blood sampling is planned for R+0, R+3-7, and R+12-15. The special handling protocol will be used here as well. Intestinal microbiota will be collected R+3-7 and R+365±30. MRIs will take place on R+30 ±7, R+180 ±30, and R+365 ±30.
Inflight, blood collection is required on Flight day 4-6 (FD4-6), FD8-12, FD 80-90, and FD165-175. Breath samples will also be collected four times on FD 4-6, FD 8-12, FD80-90, and FD 165-175. Hematocrit may be collected. Where possible, collections will be shared with other experiments/activities in order to maximize crew efficiency.
Additional data will be required in order to complete the analysis including medication, exercise, and fitness data. This data will be obtaining through data sharing agreements.
This is an international experiment. NASA does not currently have an agreement with international space partners to archive their data in the LSDA.
|Mission||Launch/Start Date||Landing/End Date||Duration|
|Expedition 46||12/11/2015||03/02/2016||82 days|
|Expedition 47||03/02/2016||06/18/2016||108 days|
|Expedition 48||06/18/2016||09/06/2016||80 days|
|Expedition 49||09/06/2016||10/30/2016||54 days|
|Expedition 50||10/28/2016||04/09/2017||164 days|
|Expedition 51||04/09/2017||06/02/2017||55 days|
|Expedition 52||06/02/2017||09/02/2017||92 days|
|Expedition 53||09/02/2017||12/14/2017||102 days|
|Expedition 54||12/14/2017||02/27/2018||75 days|
|Expedition 55||02/27/2018||06/03/2018||96 days|
|Expedition 56||06/03/2018||10/04/2018||123 days|
|Expedition 57||10/04/2018||12/20/2018||77 days|
|Expedition 58||12/18/2018||03/14/2019||85 days|
|Expedition 59||03/14/2019||In progress|