No abstract

The aim of the study was to evaluate the effects of long-term confinement on stress-permissive neuroendocrine and immune responses in humans. Two groups of four male subjects were confined 240 days (group 240) or 110 days (group 110) in two space modules of 100 or 200 m3, respectively. During confinement, none of the volunteers developed psychic stress as could be examined and verified by a current stress test. However, in group 240 but not in group 110, the diurnal rhythm of cortisol secretion was slightly depressed and the urine excretion of norepinephrine significantly increased. The innate part of the immune system became activated as seen by a rise in the number of circulating granulocytes and the enhanced expression of beta2-integrins. In contrast, the ratio of T-helper to T-suppressor cells decreased. All these effects, observed during confinement, were even more pronounced in both groups when values of endocrinological and immunological parameters were compared between before and 1 wk after the end of the confinement period. Hence, return to normal life exerts pronounced effects to a much higher degree, irrespective of how long or under which conditions individuals were confined. Because the delayed-type hypersensitivity skin reaction against recall antigens remained unaffected, it is to be presumed that confinement appears to induce distinct sympathoadrenergic activation and immunological changes but no clinically relevant immunosuppression.

No abstract

During the entire time that cosmonauts stay on board the international space station, different extreme space flight factors affect their bodies. In order to find out what physiological changes occur under the influence of spaceflight, different parameters of the human body before and after flights are monitored. Analysis of the urine proteome is one of the most perspective non-invasive methods of condition monitoring. The aim of the study was to perform a comparative semi-quantitative label-free urine proteome analysis of samples collected from 21 cosmonauts before and after long-duration spaceflight at the international space station. For proteomic analysis, urine samples were collected from cosmonauts at three time periods: six months prior to the flight as a background, and on days 1 and 7 of the recovery period after landing. All probes were analyzed by LC-MS/MS, and 256 proteins were identified with more than one unique peptide. The core proteome consists of 50 proteins that are detected in more than 70% of the samples. Label-free semi-quantitative analysis enables us to find 20 proteins which were significantly changed on +1 day and +7 day with respect to background. Most of these proteins participate in the regulation of biological processes, in the regulation of the immune system and in intracellular processes also; some of these proteins are related with stress and response to stimulus. In conclusion, the proteomic analysis of cosmonauts' urine samples provides new data on the human body's adaptation to ground conditions after long-duration spaceflight.

No abstract