title: Early adaption to the antarctic environment at dome C: consequences on stress-sensitive innate immune functions.
abstract: Abstract Feuerecker, Matthias, Brian Crucian, Alex P. Salam, Ales Rybka, Ines Kaufmann, Marjan Moreels, Roel Quintens, Gustav Schelling, Manfred Thiel, Sarah Baatout, Clarence Sams, and Alexander Choukèr. Early adaption in the Antarctic environment at Dome C: Consequences on stress-sensitive innate immune functions. High Alt Med Biol 15:341-348, 2014.-Purpose/Aims: Medical reports of Antarctic expeditions indicate that health is affected under these extreme conditions. The present study at CONCORDIA-Station (Dome C, 3233 m) seeks to investigate the early consequences of confinement and hypobaric hypoxia on the human organism.
  
  
  METHODS
  Nine healthy male participants were included in this study. Data collection occurred before traveling to Antarctica (baseline), and at 1 week and 1 month upon arrival. Investigated parameters included basic physiological variables, psychological stress tests, cell blood count, stress hormones, and markers of innate immune functions in resting and stimulated immune cells. By testing for the hydrogen peroxide (H2O2) production of stimulated polymorphonuclear leukocytes (PMNs), the effects of the hypoxia-adenosine-sensitive immune modulatory pathways were examined.
  
  
  RESULTS
  As compared to baseline data, reduced oxygen saturation, hemoconcentration, and an increase of secreted catecholamines was observed, whereas no psychological stress was seen. Upon stimulation, the activity of PMNs and L-selectin shedding was mitigated after 1 week. Endogenous adenosine concentration was elevated during the early phase. In summary, living conditions at high altitude influence the innate immune system's response. After 1 month, some of the early effects on the human organism were restored.
  
  
  CONCLUSIONS
  As this early adaptation is not related to psychological stress, the changes observed are likely to be induced by environmental stressors, especially hypoxia. As hypoxia is triggering ATP-catabolism, leading to elevated endogenous adenosine concentrations, this and the increased catecholamine concentration might contribute to the early, but reversible downregulation of innate immune functions. This indicates the slope of innate immune adaptation to hypoxia.
authors.affiliation: 1 Department of Anaesthesiology, Klinikum Großhadern, University of Munich , Research Group Stress and Immunity, Munich, Germany .
authors.forename: Matthias
authors.initials: M
authors.lastname: Feuerecker
authors.forename: Brian
authors.initials: B
authors.lastname: Crucian
authors.forename: Alex P
authors.initials: AP
authors.lastname: Salam
authors.forename: Ales
authors.initials: A
authors.lastname: Rybka
authors.forename: Ines
authors.initials: I
authors.lastname: Kaufmann
authors.forename: Marjan
authors.initials: M
authors.lastname: Moreels
authors.forename: Roel
authors.initials: R
authors.lastname: Quintens
authors.forename: Gustav
authors.initials: G
authors.lastname: Schelling
authors.forename: Manfred
authors.initials: M
authors.lastname: Thiel
authors.forename: Sarah
authors.initials: S
authors.lastname: Baatout
authors.forename: Clarence
authors.initials: C
authors.lastname: Sams
authors.forename: Alexander
authors.initials: A
authors.lastname: Choukèr
mesh_terms: D000064:Acclimatization / Q000276:immunology* / Q000502:physiology; D000328:Adult; D000531:Altitude; D000864:Antarctic Regions; D015415:Biomarkers / Q000378:metabolism; D005101:Expeditions; D005500:Follow-Up Studies; D006801:Humans; D006861:Hydrogen Peroxide / Q000378:metabolism; D000860:Hypoxia / Q000209:etiology / Q000276:immunology* / Q000503:physiopathology; D007113:Immunity, Innate; D008297:Male; D008875:Middle Aged; D009504:Neutrophils / Q000378:metabolism; D013312:Stress, Physiological / Q000276:immunology*; D013315:Stress, Psychological / Q000175:diagnosis / Q000209:etiology
chemical_list: D015415:Biomarkers; D006861:Hydrogen Peroxide
keywords: Antarctica; adenosine; hormones; hypobaric hypoxia; polymorphonuclear leukocytes (PMNs)