The research team of Associate Professor Masanori Inada of Tokyo University of Agriculture and Technology conducted a mouse breeding experiment in a variable gravity environment by utilizing space experiments and ground experiments, and appropriate gravity load and movement are muscles regardless of space or ground. And discovered that it maintains and increases bones.The results of this research are based on international joint research with Oxford University and Japan Aerospace Exploration Agency (JAXA).
This time, in the International Space Station "Kibo", mice were bred for one month in the same 1G gravity environment as on the earth by a micro-gravity environment or a centrifugal breeding device, and comparative analysis was performed. Mice were bred for 1 weeks in a 1G gravity environment with a breeding device for comparative analysis, and the effect on musculoskeletal tissues was analyzed.
As a result, in the bone analysis of long-term space-staying mice under microgravity, the bone mass of the humerus and tibia decreased, but the bone mass did not decrease in the breeding by 1G artificial gravity.In 2G-loaded mice, the bone mass of the parietal bone, humerus bone, femur, and tibia increased, the gene expression of the bone formation system and bone resorption system increased, and the muscles of the lower leg muscles (knee to ankle muscles) became enlarged.In hypertrophy, the expression of muscle control gene group was increased and the expression of myolytic gene group was suppressed at the same time, and the lower leg muscle mass was significantly increased.
From these results, it was found that living movements under different gravity are involved in the quantitative control of muscles and bones.It was also found that the 2G gravity load increases muscle and bone mass and is a gravity load range suitable for maintaining the musculoskeletal system.Appropriate gravitational loads are thought to maintain and increase muscles and bones, both in space and on the ground.
It is expected that the results of this research will lead to the development of preventive and therapeutic methods for locomotive syndrome (a condition in which disorders of the locomotive organs cause problems in daily life), which is a problem to be solved in an aging society.
Paper information:[Scientific Reports] Hypergravity and microgravity exhibited reversal effects on the bone and muscle mass in mice
