Effects of traditional Chinese medicines on murine bone metabolism in a microgravity environment

We investigated the effects of three traditional Chinese medicine prescriptions on changes of bone metabolism in mice, using a gravity device to produce a microgravity environment. We found that Hochu-ekki-to (TJ-41) and Hachimi-jio-gan (TJ-7) suppress the increase in the ratio of serum Ca/P and the increase of calcium in urine. Moreover, TJ-41 and Shin-bu-to (TJ-30) reversed the increase of alkaline phosphatase activity (ALP), and TJ-41 also reversed the decrease of estradiol in the serum. The mechanism may be that the traditional Chinese medicines increased estradiol, causing the decrease of ALP, which induced the changes of Ca and P in serum, leading to a decreased excretion of Ca in urine. In this study, TJ-41 was effective in every parameter while TJ-7 and TJ-30 was effective on some parameters, showing that traditional Chinese medicines have specificities in the space environment. In conclusion, this study suggests that some traditional Chinese medicines may be beneficial for adaptation to a space environment.