The osteoprotective effect of Radix Dipsaci extract in ovariectomized rats

Aim: The objective of the present study was to systematically evaluate the effects of Radix Dipsaci extract (RDE) on postmenopausal osteoporosis. Materials and methods: OVX or sham operations were performed on sixty 3-month-old virgin Sprague-Dawley rats that were divided into six groups: sham control group (sham, n = 10): OVX control group (OVX, n = 10): 17 beta-estradiol treatment group (E2, n = 10); three Radix Dipsaci extract treatment groups RDE100 (n = 10), RDE300 (n = 10) and RDE500 (n = 10). The treatment began 4 weeks after the surgery and lasted for 16 weeks. Bone mass, bone turnover and strength were analyzed by DEXA, biochemical markers and three-point bending test. The trabecular bone microarchitecture was evaluated by MicroCT. Results: 16 weeks treatment of RDE slowed down the body weight gain and prevented the loss of bone mass induced by the OVX. The prevention effect on bone loss was due to altering the rate of bone remodeling, which could be inferred from the decreased level of bone turnover markers, such as serum ALP, OC and urinary DPD. The changes of urinary calcium and phosphorus excretion provided the same evidence. The treatment could also enhance the bone strength and prevent the deterioration of trabecular microarchitecture. Conclusions: Our study provides evidence that Radix Dipsaci extract will have potential to be used for treatment of postmenopausal osteoporosis. (C) 2009 Elsevier Ireland Ltd. All rights reserved.