BACKGROUND: Spaceflight is associated with increased glucocorticoids and catecholamines, both well-known for their immunosuppressive effects. The objective of this study was to develop a model of spaceflight by using a human centrifuge to reproduce launch and landing G forces along with bed rest to simulate microgravity. HYPOTHESIS: Acute changes in G forces are causal factors in neuroendocrine and immune changes. METHODS: Ten subjects underwent realistic launch G-force profiles followed by 16 d of 60 head-down tilt bed rest. At the end of the bed rest, subjects were subjected to realistic landing G-force profiles. Stress hormones and changes in leukocyte and lymphocyte subsets were measured in blood and urine samples over the course of the study. RESULTS: Similar to shorter Shuttle missions (i.e., < or = 9 d), plasma cortisol was significantly decreased at simulated landing while urinary epinephrine was significantly increased. Urinary cortisol was significantly increased after simulated launch. The pattern of leukocyte and lymphocyte changes also mirrored the changes found in shorter 9-d spaceflights. CONCLUSIONS: These data suggest a role for both catecholamines and glucocorticoids in mediating changes in leukocyte and lymphocyte subsets during simulated microgravity coupled with hypergravity. Our results were also strikingly similar to those from actual Shuttle missions and support our conclusion that we have developed a model of spaceflight.
BACKGROUND: Spaceflight is associated with increased glucocorticoids and catecholamines, both well-known for their immunosuppressive effects. The objective of this study was to develop a model of spaceflight by using a human centrifuge to reproduce launch and landing G forces along with bed rest to simulate microgravity. HYPOTHESIS: Acute changes in G forces are causal factors in neuroendocrine and immune changes. METHODS: Ten subjects underwent realistic launch G-force profiles followed by 16 d of 60 head-down tilt bed rest. At the end of the bed rest, subjects were subjected to realistic landing G-force profiles. Stress hormones and changes in leukocyte and lymphocyte subsets were measured in blood and urine samples over the course of the study. RESULTS: Similar to shorter Shuttle missions (i.e., < or = 9 d), plasma cortisol was significantly decreased at simulated landing while urinary epinephrine was significantly increased. Urinary cortisol was significantly increased after simulated launch. The pattern of leukocyte and lymphocyte changes also mirrored the changes found in shorter 9-d spaceflights. CONCLUSIONS: These data suggest a role for both catecholamines and glucocorticoids in mediating changes in leukocyte and lymphocyte subsets during simulated microgravity coupled with hypergravity. Our results were also strikingly similar to those from actual Shuttle missions and support our conclusion that we have developed a model of spaceflight.
Authors: Paula Hoff; Daniel L Belavý; Dörte Huscher; Annemarie Lang; Martin Hahne; Anne-Kathrin Kuhlmey; Patrick Maschmeyer; Gabriele Armbrecht; Rudolf Fitzner; Frank H Perschel; Timo Gaber; Gerd-Rüdiger Burmester; Rainer H Straub; Dieter Felsenberg; Frank Buttgereit Journal: Cell Mol Immunol Date: 2014-11-10 Impact factor: 11.530
Authors: A Choukèr; B Feuerecker; S Matzel; I Kaufmann; C Strewe; M Hoerl; G Schelling; M Feuerecker Journal: Eur J Appl Physiol Date: 2013-04-12 Impact factor: 3.078
Authors: Satish K Mehta; Stephen K Tyring; Randall J Cohrs; Don Gilden; Alan H Feiveson; Kayla J Lechler; Duane L Pierson Journal: J Virol Methods Date: 2013-06-05 Impact factor: 2.014
Authors: Naomi E Brooks; Samuel M Cadena; Gregory Cloutier; Sonia Vega-López; Ronenn Roubenoff; Carmen Castaneda-Sceppa Journal: Int J Med Sci Date: 2014-09-21 Impact factor: 3.738