Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2022 Aug 3;23(15):8650.
doi: 10.3390/ijms23158650.

Microgravity-Related Changes in Bone Density and Treatment Options: A Systematic Review

Ronni Baran  1 , Markus Wehland  2   3 , Herbert Schulz  2   3 , Martina Heer  4   5 , Manfred Infanger  2   3 , Daniela Grimm  1   2   3
Affiliations

Microgravity-Related Changes in Bone Density and Treatment Options: A Systematic Review

Ronni Baran et al. Int J Mol Sci. .

Abstract

Space travelers are exposed to microgravity (µg), which induces enhanced bone loss compared to the age-related bone loss on Earth. Microgravity promotes an increased bone turnover, and this obstructs space exploration. This bone loss can be slowed down by exercise on treadmills or resistive apparatus. The objective of this systematic review is to provide a current overview of the state of the art of the field of bone loss in space and possible treatment options thereof. A total of 482 unique studies were searched through PubMed and Scopus, and 37 studies met the eligibility criteria. The studies showed that, despite increased bone formation during µg, the increase in bone resorption was greater. Different types of exercise and pharmacological treatments with bisphosphonates, RANKL antibody (receptor activator of nuclear factor κβ ligand antibody), proteasome inhibitor, pan-caspase inhibitor, and interleukin-6 monoclonal antibody decrease bone resorption and promote bone formation. Additionally, recombinant irisin, cell-free fat extract, cyclic mechanical stretch-treated bone mesenchymal stem cell-derived exosomes, and strontium-containing hydroxyapatite nanoparticles also show some positive effects on bone loss.

Keywords: animals; astronauts; bone loss; cells; countermeasures; microgravity; pharmacology; signaling pathways; spaceflight.

PubMed Disclaimer

Conflict of interest statement

The authors declare no conflict of interest.

Figures

Figure 1
Figure 1
The treatment of menopausal osteoporosis. Abbreviations: RANKL, receptor activator of nuclear factor κβ ligand; SERMS, selective estrogen receptor modulator; Scl-Ab, antisclerostin antibody [10,16,19]. The insert shows the Scl-Ab’s dual mode of action in more detail. Created with BioRender.com (accessed on 27 July 2022).
Figure 2
Figure 2
Mechanisms of microgravity (µg)-induced bone loss: µg releases calcium from bone, which suppresses the parathyroid hormone (PTH). Afterward, the suppressed PTH then lowers the circulating 1,25-dihydroxyvitamin D. This leads to decreased calcium absorption [24,26,27,28]. Additionally, osteoblast function is impaired, and osteocyte apoptosis is increased [5,32]. This results in unchanged or decreased bone formation and increased bone resorption, which leads to bone loss [22,23,24]. Created with BioRender.com (accessed on 27 July 2022).
Figure 3
Figure 3
Search terms in PubMed.
Figure 4
Figure 4
Flowchart of study selection.
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

References

    1. Morphew M.E. Psychological and human factors in long duration spaceflight. McGill J. Med. 2001;6:74–80. doi: 10.26443/mjm.v6i1.555. - DOI
    1. Furukawa S., Nagamatsu A., Nenoi M., Fujimori A., Kakinuma S., Katsube T., Wang B., Tsuruoka C., Shirai T., Nakamura A.J., et al. Space Radiation Biology for “Living in Space”. Biomed. Res. Int. 2020;2020:4703286. doi: 10.1155/2020/4703286. - DOI - PMC - PubMed
    1. Shen M., Frishman W.H. Effects of Spaceflight on Cardiovascular Physiology and Health. Cardiol Rev. 2019;27:122–126. doi: 10.1097/CRD.0000000000000236. - DOI - PubMed
    1. Hughes-Fulford M. To infinity … and beyond! Human spaceflight and life science. FASEB J. 2011;25:2858–2864. doi: 10.1096/fj.11-0902ufm. - DOI - PMC - PubMed
    1. Juhl O.J.T., Buettmann E.G., Friedman M.A., DeNapoli R.C., Hoppock G.A., Donahue H.J. Update on the effects of microgravity on the musculoskeletal system. NPJ Microgravity. 2021;7:28. doi: 10.1038/s41526-021-00158-4. - DOI - PMC - PubMed

Publication types

Substances

LinkOut - more resources