The combined effects of simulated microgravity and X-ray radiation on MC3T3-E1 cells and rat femurs

• Published in: NPJ microgravity Vol. 7; no. 1; pp. 3 - 8
• Main Authors: Dong, Jingjing, Wang, Honghui, Li, Gaozhi, Wang, Ke, Tan, Yingjun, Zhang, Lijun, Wang, Yixuan, Hu, Zebing, Cao, Xinsheng, Shi, Fei, Zhang, Shu
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 15.02.2021; Nature Publishing Group; Nature Portfolio
• Subjects: 631/45; 631/80; Apoptosis; Applied Microbiology; Biomedical and Life Sciences; Biotechnology; Bone loss; Caspase-3; Cbfa-1 protein; Classical and Continuum Physics; Collagen; Computed tomography; Flow cytometry; Immunology; Life Sciences; Microgravity; mRNA; Osteopenia; Space Exploration and Astronautics; Space Sciences (including Extraterrestrial Physics; X-rays
• ISSN: 2373-8065; 2373-8065
• DOI: 10.1038/s41526-021-00131-1

Microgravity is well-known to induce Osteopenia. However, the combined effects of microgravity and radiation that commonly exist in space have not been broadly elucidated. This research investigates the combined effects on MC3T3-E1 cells and rat femurs. In MC3T3-E1 cells, simulated microgravity and X-ray radiation, alone or combination, show decreased cell activity, increased apoptosis rates by flow cytometric analysis, and decreased Runx2 and increased Caspase-3 mRNA and protein expressions. In rat femurs, simulated microgravity and X-ray radiation, alone or combination, show increased bone loss by micro-CT test and Masson staining, decreased serum BALP levels and Runx2 mRNA expressions, and increased serum CTX-1 levels and Caspase-3 mRNA expressions. The strongest effect is observed in the combined group in MC3T3-E1 cells and rat femurs. These findings suggest that the combination of microgravity and radiation exacerbates the effects of either treatment alone on MC3T3-E1 cells and rat femurs.