Treatment effect of Bushen Huayu extract on postmenopausal osteoporosis in vivo

Bushen Huayu extract (BSHY), a traditional Chinese medicine, has been demonstrated to treat postmenopausal osteoporosis, however, the underlying mechanism remains to be fully elucidated. The aim of the present study was to investigate the therapeutic effect of BSHY and the mechanisms underlying this effect in an in vivo postmenopausal osteoporosis animal model. A total of 1 g BSHY containing 7.12 μg icariin was prepared. Low-dose BSHY (BSHY-L; 11.1 g/kg), medium-dose BSHY (BSHY-M; 22.2 g/kg) and high-dose BSHY (BSHY-H; 44.4 g/kg) was administered to oophorectomized rats using intragastric infusion. Estradiol (E2), interleukin-6 (IL-6) and serum alkaline phosphatase (ALP) levels, as well as bone density, were determined. It was found that the levels of serum ALP in the BSHY-L, BSHY-M and BSHY-H groups (197.75±41.74, 166.63±44.83 and 165.63±44.90 IU/l, respectively) were significantly decreased compared with the model group (299.13±45.79 IU/l; P<0.05), whilst the levels of E2 (16.89±1.71, 17.95±1.40 and 18.34±1.43 pg/ml, respectively) increased compared with the model group (14.54±1.61; P<0.05). In addition, the levels of IL-6 decreased in the BSHY-L, BSHY-M and BSHY-H groups (91.85±14.81, 82.99±15.65 and 80.54±14.61 pg/ml, respectively) compared with the model group (105.93±16.50 pg/ml; P<0.05). Furthermore, it was demonstrated that BSHY increased the bone density in the BSHY-L, BSHY-M and BSHY-H groups (0.20±0.014, 0.22±0.016 and 0.22±0.017 g/cm(2), respectively) compared with the model group (0.19±0.011 g/cm(2); P<0.05). BSHY was also found to increase the number of osteoblasts in the BSHY-L, BSHY-M and BSHY-H groups (25.38±2.17, 29.25±2.12 and 30.00±2.39, respectively), compared with in the model group (14.75±2.38; P<0.05), and decrease the number of osteoclasts in the BSHY-L, BSHY-M and BSHY-H groups (4.00±1.85, 4.25±1.39 and 5.75±1.49, respectively) compared with 9.50±1.60 observed in the model group (P<0.05). These results suggest that BSHY is a potential therapeutic drug for the treatment of osteoporosis in vivo. Furthermore, these results suggest that the mechanism by which BSHY decreases the serum levels of IL-6 may be by regulating E2.