Effect of total flavones of Epimedium leptorrhizum on osteoporosis in ovariectomized rats

OBJECTIVE: To observe the effect of total flavones of Epimedium leptorrhizum (YYH-C) on osteoporosis in ovariectomized rats. METHOD: Ovariectomized female rats were randomly divided into the model group, YYH-C lower, middle and high dose (0.7, 1.4, 2.8 g x kg(-1)) groups, the positive drug Bujiale (0.15 mg x kg(-1)) group, and the sham group. The rats were orally ad-ministrated with drugs for three months. Parathyroid hormone (PTH), procollagen I N-terminal peptide (PINP), alkaline phosphatase (ALP), calcium (Ca) and phosphrous (P) in serum were detected. Femur bones and vertebrae bones of left side were collected to determined bone metrological indexes, including bone mineral density (BMD), bone Ca, and bone ash weight/dry weight percentage. Femur bones of right side were collected to for a morphological observation of bone. RESULT: Compared with the sham group, the model group showed significantly higher PTH and ALP content but obviously lower PINP and Ca content. The three YYH-C 3 groups could resist the decrease of PINP. Specifically, low and middle dose groups could remarkably inhibit the increase of PTH, and the high dose group could increase the Ca content in serum, but without significant effect on the rise in ALP. There was no significant difference in P content in serum in each group. BMD, ash weight/dry weight percentage, Ca and P content of the model group were significantly lower than those in the sham group. The high dose YYH-C group could significantly increase BMD. All of the three YYH-C groups could notably increase ash weight/dry weight percentage and Ca, P content in femur bones and vertebrae bones. YYH-C could significantly increase average thickness, area, area percentage of bony trabeculae, cortical bone area percentage of femoral shaft and the number of osteoblasts on the surface of bony trabeculae, and decrease the number of osteoclasts. CONCLUSION: YYH-C can effectively control the bone mass loss of rats with ovariectomy-induced osteoporosis, prevent the changes in bone microstructure, and inhibit bone absorption, so as to resist high turn-over osteoporosis after ovariectomy. [Key words] total flavones of Epimedium leptorrhizum; ovariectomized rat; osteoporosis