BLOOD AND OXIDATIVE STRESS (BOS)
Research Area: Integrated Physiology and Nutrition
Expedition(s): 10, 11
Principal Investigator(s): ● Angela Maria Rizzo, PhD, Berra University of Milan, Italy
● Laura Adorni, Berra University of Milan, Italy
● Gigliola Montorfano, Berra University of Milan, Italy
● Manuela Negroni, Berra University of Milan, Italy
● Stefania Zava, Berra University of Milan, Italy
RESEARCH OBJECTIVES
Loss of red blood cell mass, volume of blood plasma, and hemoglobin (space anemia) has been
continuously observed in space explorers. Blood and Oxidative Stress (BOS) aims to determine
the degree of stress that the red blood cells have undergone to bring about cell damage, the
quantity of substances in blood serum that would prevent this damage (antioxidants), the
damage to red blood cell membranes, and the time it takes to recover. BOS aims to find
methods to reduce the current effects of oxidative space anemia by integrating appropriate
dietary elements and natural compounds that act as antioxidants. These results also impact
medical planning for future longer duration space missions beyond low-Earth orbit.
RESULTS
To determine the effects of spaceflight on the erythrocyte antioxidant potential, an assay of the
glutathione content and the enzyme connected with Reactive Oxygen Species (ROS)
detoxification was made. Spaceflight reduced glutathione content and also the activity of
glutathione peroxidase. Both these parameters were recovered 15 days postflight with an
increase of peroxidases activity. It was possible to observe that all the activities were
significantly reduced in other enzymes involved in ROS detoxification after flight, in particular
the activity of glutathione reductase. All the enzymes were increased at 15 days postflight. Also
erythrocyte cell membrane was affected by spaceflight with a reduction of the cholesterol and
phospholipid contents indicating that the phospholipids/cholesterol ratio was maintained
constant. At 15 days postflight, there was an increase of phospholipids and consequently of the
phospholipid/cholesterol ratio. All together these data indicated that a short time spaceflight
might induce “space anemia” with a reduction in hemoglobin content of red blood cells.
Over the past 15 years, space medicine has become increasingly concerned with the effects of
spaceflight on hematological processes; astronauts have consistently returned from spaceflight
with a decreased red blood cell mass spaceflight anemia and plasma volume. Although plasma
volume is known to be labile, current theories for the control of erythropoiesis cannot account
for a decrease in red blood cell mass of 10% in <10 days. Experimental data confirmed these
observations and point out: a decrease of antioxidant defenses in red blood and a modification
of cell membrane composition. These might be the consequences of increased cell aging due to
exposure during flight to increased oxidative stress. The data on enzyme activities could be the
first reported in literature, even though they need further investigation to confirm their
importance. If these observations are confirmed, they might be utilized to integrate astronaut’s
diet with appropriate antioxidant aliment or supplements.