Dex injection caused a significant reduction in the levels of factors related to osteoblast differentiation, including ALP, collagen I, OCN, OPN, BMP2 and BMPR2, and in the levels of Ca, Pi and E2 in the peripheral blood of Dex-injected mice with osteoporosis (P <0.05) (Table 1), which were strongly enhanced after 8 weeks’ AU and E2 administration (P <0.05) (Table 1). Here, BMPR2 is linked to osteoporosis.