Abstract:

BACKGROUND: Xianzhengubao capsule made from Cnidium, Epimedium and others has a certain protective role in glucocorticoid and retinoic acid-induced osteoporosis.
OBJECTIVE: To study the effect of Xianzhengubao on different bones in prednisone-treated rats by bone histomorphometry and bone biomechanics methods.
METHODS: Thirty-two Sprague-Dawley rats were randomly divided into control, prednisone, high- and low-dose Xianzhengubao groups. Rats in the latter groups were given prednisone at 3.5 mg/kg•d first to establish osteoporosis models. High- and low-dose Xianzhengubao groups were administrated with Xianzhengubao capsule at 0.95 g/kg•d and 0.475 g/kg•d, respectively, after prednisone treatment.
RESULTS AND CONCLUSION: Compared with the control group, bone mineral density and biomechanical properties (elastic load, maximum load, break load) of the femur were significantly decreased in the prednisone group. Percent labeled perimeter, bone formation rate per bone surface and per unit of bone volume of the proximal tibial metaphysis were decreased in the prednisone group, but there was no significant difference both in static parameters of proximal tibial metaphysis and in tibial shaft. Compared with the prednisone group, bone mineral density and biomechanical properties of the femur, percent labeled perimeter and bone formation rate per bone surfaceof the proximal tibial metaphysis were increased, but there was no significant change in tibial shaft in the high-dose Xianzhengubao group. Compared with the prednisone group, there was no significant change in the low-dose Xianzhengubao group. The results demonstrates the Xianzhengubao can promote bone formation and prevent the decrease of bone mineral density and biomechanical properties of the femur in prednisone-treated rats, but has no effect on the cortical bone of the tibial shaft.