BRIEF RESEARCH REPORT article
Front. Physiol.
Sec. Environmental, Aviation and Space Physiology
Volume 16 - 2025 | doi: 10.3389/fphys.2025.1600708
Alterations in CNS-derived Blood Biomarkers During 30 Days Simulated Microgravity
Provisionally accepted
Susanne Viktoria Schmidt1
Alexandru Oudainic1,2
Petra Frings-Meuthen3
Jan Hönemann3
Maria Bohmeier3
Christian Liemersdorf3
Edwin Mulder3
Stefan Möstl3
Karsten Heusser3
Jens Tank3
Jens Jordan3
Laura de Boni3*- 1University Hospital Bonn, Bonn, Nordrhein-Westfalen, Germany
- 2NEC OncoImmunity AS, Oslo, Norway
- 3German Aerospace Center (DLR), Cologne, North Rhine-Westphalia, Germany
Select one of your emails
You have multiple emails registered with Frontiers:
Notify me on publication
Please enter your email address:
If you already have an account, please login
You don't have a Frontiers account ? You can register here
Spaceflight induces physiological adaptations, including headward fluid shifts that may impact the central nervous system (CNS). Ground-based analogs such as 6° head-down tilt bed rest (HDTBR) provide a controlled setting to study these neurophysiological effects and assess CNS biomarkers. We therefore analyzed neurological function and CNS-derived blood biomarkers during four NASAbacked 30-day strict HDTBR campaigns to better understand neurophysiological responses to prolonged fluid redistribution.Forty participants (18 women, 22 men; mean age ~36 years) were assigned to different countermeasure groups: lower body negative pressure (LBNP), cycling in HDT followed by wearing thigh cuffs, upright sitting (positive control), and HDTBR without countermeasures. Neurological exams and blood biomarker analyses (SIMOA Quanterix) were performed to assess NfL, GFAP, Aβ40, Aβ42, and total tau.No clinical neurological impairments were observed. The LBNP group exhibited robust increases in amyloid-related biomarkers during HDTBR, which persisted into the recovery period. Analysis of within-subject changes over time revealed additional effects. In the cycling and cuffs group, NFL levels increased progressively throughout the study. In the control group, GFAP levels rose gradually, indicating mild glial activation. Tau protein also increased in the LBNP group but returned to baseline levels during the recovery phase.These findings highlight subtle but biologically relevant CNS-related changes in response to different countermeasure strategies during 30-day strict HDTBR. LBNP may enhance metabolite clearance, as reflected in increased Aβ washout. These findings support the use of LBNP as a potential countermeasure to protect brain health during spaceflight and analog missions.
Keywords: head down tilt bed rest, CNS, biomarker, Neurons, glia
Received: 26 Mar 2025; Accepted: 03 Jun 2025.
Copyright: © 2025 Schmidt, Oudainic, Frings-Meuthen, Hönemann, Bohmeier, Liemersdorf, Mulder, Möstl, Heusser, Tank, Jordan and de Boni. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
* Correspondence: Laura de Boni, German Aerospace Center (DLR), Cologne, 51147, North Rhine-Westphalia, Germany
Disclaimer: All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article or claim that may be made by its manufacturer is not guaranteed or endorsed by the publisher.