title: The impact of chronic stress burden of 520-d isolation and confinement on the physiological response to subsequent acute stress challenge.
abstract: Collective evidence indicates that previous exposure to stressful condition might be able to induce changes in brain structure, HPA axis activity and related neurotransmission, and accordingly affect physiological responses to subsequent challenges. During long-term spaceflight, space travelers have to live under the condition of isolation and confinement in the spacecraft for a long period. It is still largely unknown if this kind of chronic stress burden can induce any long-lasting changes. To address this question, following 520-d isolation and confinement simulating a flight to Mars, the participants and a matched control group were exposed to an acute stress challenge called parabolic flight. Brain cortical activity, HPA axis activity, and sympathetic adrenal-medullary system response were monitored by EEG signal, cortisol secretion, and catecholamine production, respectively. We observed enhanced EEG signals, elevated cortisol levels and increased adrenaline productions. A group effect on cortisol output was revealed showing higher cortisol peak levels in the Mars520 group as compared to the control group, suggesting that HPA axis was to a certain extent more activated in the subjects who had chronic stress experience.
authors.affiliation: Department of Anaesthesiology (Research Group Stress and Immunology), Hospital of the University of Munich (LMU), Munich, Germany. Electronic address: buqing.yi@med.uni-muenchen.de.
authors.forename: Buqing
authors.initials: B
authors.lastname: Yi
authors.affiliation: Department of Anaesthesiology (Research Group Stress and Immunology), Hospital of the University of Munich (LMU), Munich, Germany.
authors.forename: Sandra
authors.initials: S
authors.lastname: Matzel
authors.affiliation: Department of Anaesthesiology (Research Group Stress and Immunology), Hospital of the University of Munich (LMU), Munich, Germany.
authors.forename: Matthias
authors.initials: M
authors.lastname: Feuerecker
authors.affiliation: Department of Anaesthesiology (Research Group Stress and Immunology), Hospital of the University of Munich (LMU), Munich, Germany.
authors.forename: Marion
authors.initials: M
authors.lastname: Hörl
authors.affiliation: Department of Anaesthesiology (Research Group Stress and Immunology), Hospital of the University of Munich (LMU), Munich, Germany.
authors.forename: Camilla
authors.initials: C
authors.lastname: Ladinig
authors.affiliation: Institute of Movement and Neurosciences, German Sport University Cologne, Cologne, Germany.
authors.forename: Vera
authors.initials: V
authors.lastname: Abeln
authors.affiliation: Department of Anaesthesiology (Research Group Stress and Immunology), Hospital of the University of Munich (LMU), Munich, Germany. Electronic address: alexander.chouker@med.uni-muenchen.de.
authors.forename: Alexander
authors.initials: A
authors.lastname: Choukèr
authors.affiliation: Institute of Movement and Neurosciences, German Sport University Cologne, Cologne, Germany; Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Maroochydore, Queensland, Australia. Electronic address: Schneider@dshs-koeln.de.
authors.forename: Stefan
authors.initials: S
authors.lastname: Schneider
mesh_terms: D000324:Adrenocorticotropic Hormone / Q000097:blood; D000328:Adult; D001921:Brain / Q000502:physiology*; D016022:Case-Control Studies; D004569:Electroencephalography; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000032:analysis; D007030:Hypothalamo-Hypophyseal System / Q000378:metabolism*; D008297:Male; D009483:Neuropsychological Tests; D010913:Pituitary-Adrenal System / Q000378:metabolism*; D013315:Stress, Psychological / Q000378:metabolism* / Q000523:psychology*; D013997:Time Factors
chemical_list: D000324:Adrenocorticotropic Hormone; D006854:Hydrocortisone
keywords: Chronic stress; Cortisol; EEG; HPA axis activity