Sixty days of head-down tilt bed rest with or without artificial gravity do not affect the neuromuscular secretome

Exp Cell Res. 2021 Feb 15;399(2):112463. doi: 10.1016/j.yexcr.2020.112463. Epub 2020 Dec 29.


Artificial gravity is a potential countermeasure to attenuate effects of weightlessness during long-term spaceflight, including losses of muscle mass and function, possibly to some extent attributable to disturbed neuromuscular interaction. The 60-day AGBRESA bed-rest study was conducted with 24 participants (16 men, 8 women; 33 ± 9 years; 175 ± 9 cm; 74 ± 10 kg; 8 control group, 8 continuous (cAG) and 8 intermittent (iAG) centrifugation) to assess the impact of bed rest with or without daily 30-min continuous/intermittent centrifugation with 1G at the centre of mass. Fasting blood samples were collected before and on day 6, 20, 40 and 57 during 6° head-down tilt bed rest. Concentrations of circulating markers of muscle wasting (GDF-8/myostatin; slow skeletal muscle troponin T; prostaglandin E2), neurotrophic factors (BDNF; GDNF) and C-terminal Agrin Fragment (CAF) were determined by ELISAs. Creatine kinase activity was assessed by colorimetric enzyme assay. Repeated-measures ANOVAs were conducted with TIME as within-subject, and INTERVENTION and SEX as between-subject factors. The analyses revealed no significant effect of bed rest or sex on any of the parameters. Continuous or intermittent artificial gravity is a safe intervention that does not have a negative impact of the neuromuscular secretome.

Keywords: Astronaut; BDNF; C-terminal agrin fragment; Disuse; Microgravity; Spaceflight.

Publication types

  • Controlled Clinical Trial
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Adult
  • Bed Rest* / adverse effects
  • Case-Control Studies
  • Female
  • Gravity, Altered* / adverse effects
  • Head-Down Tilt / adverse effects
  • Head-Down Tilt / physiology*
  • Humans
  • Male
  • Middle Aged
  • Muscle, Skeletal / innervation
  • Muscle, Skeletal / metabolism*
  • Muscular Atrophy / etiology
  • Muscular Atrophy / metabolism
  • Nervous System Physiological Phenomena
  • Proteome / metabolism*
  • Secretory Pathway
  • Time Factors
  • Young Adult


  • Proteome