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Updated: May 9, 2026
09:32
Subject-specific Musculoskeletal Model for Studying Bone Strain During Dynamic Motion
Published on: April 11, 2018
ESA VIVALDI (1 & 2) campaigns: sex-specific bone responses to dry immersion-induced unloading
Peter Fernandez1, Marie-Thérèse Linossier1, Marie Pierre Bareille2
1SAINBIOSE - U1059, Université Jean Monnet Saint-Étienne, Mines Saint Etienne, INSERM, Saint-Etienne, France.
Summary
Sex differences in bone deconditioning during simulated microgravity were investigated. Females exhibited greater bone resorption and persistent reductions in periostin, suggesting a faster progression toward bone loss compared to males.
Area of Science:
- Space physiology
- Bone biology
- Metabolic homeostasis
Background:
- Skeletal unloading from microgravity rapidly disrupts bone and metabolic homeostasis.
- Sex-specific responses to unloading are not well understood.
- Dry immersion (DI) simulates microgravity, allowing study of early bone deconditioning.
Purpose of the Study:
- To assess sex differences in biochemical markers of bone and energy metabolism during DI.
- To investigate early determinants of unloading-induced bone deconditioning.
- To identify potential biomarkers for sex-specific countermeasures.
Main Methods:
- Two 5-day European Space Agency DI campaigns (VIVALDI 1 and 2).
- Involved healthy males (n=19) and females (n=18).
- Assessed biochemical markers of bone remodelling and energy metabolism.
Main Results:
- DI rapidly increased bone resorption in both sexes, with greater TRAP5b increase in females.
- Bone formation markers (PINP, osteocalcin) declined similarly in both sexes.
- Females showed more marked and persistent reductions in periostin compared to males.
- Calcium increased transiently, PTH declined, IGF-1 and visfatin increased in both sexes.
Conclusions:
- Both sexes experience early bone deconditioning during DI.
- Females exhibit greater bone resorption and periostin reduction, indicating faster bone loss progression.
- Early sex-specific responses highlight potential biomarkers for targeted countermeasures against spaceflight- and immobilization-related bone loss.
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