Effect of epimedium on blood rheology and bone density of rats with steroid-induced femoral head necrosis

Objective To observe the effect of epimedium extract on blood rheology and bone density of rats with steroid-induced femoral head necrosis.Methods Thirty-two healthy SD rats were selected,half of female and half of male,and randomly divided into four groups:control group,model group,highdose epimedium group and low-dose epimedium group,8 rats in each group.The steroid-induced femoral head necrosis models were established by gluteal injection of prednisolone acetate injection in last three groups. High-dose epimedium group and low-dose epimedium group were given the concentration of 1.5g/l and 0.9 g/L crude drugs containing epimedium extract 10 ml/kg respectively,and model group and blank group were given the same dose of normal saline,6 weeks.Results After gastric infusion for 6 weeks,the whole blood high shear viscosity in high-dose epimedium group and low-dose epimedium group was (5.55 ±0.60) and (5.85 ±0.66) ms/s,and the plasma viscosity was( 1.88 ±0.10) and (1.93 ±0.17) ms/s,respectively,which were significantly higher than those in control group ( P ＜0.05 ).The whole blood high shear viscosity and plasma viscosity in high-dose epimedium group were lower than those in the model group [(6.66± 0.65 ),(2.11± 0.21 ) ms/s,P ＜ 0.05].The whole blood low shear viscosity and hematocrit in high-dose epimedium group were (9.96 ±0.68 ) and (0.48 ±0.05 ) ms/s respectively,which were lower than those in model group ( P ＜ 0.05 ) and low-dose epimedium group [( 10.97 ±0.67) and (0.57 ±0.05) ms/s,P ＜0.05)].The bone density in high-dose epimedium group and control group was higher than that in low-dose epimedium group and model group ( P ＜ 0.05 ).Conclusion The mechanism of high-dose epimedium extract for the treatment of steroid-induced femoral head necrosis may be related with many factors such as to reduce the blood rheology indicators,ensure the effective perfusion of organization and improve the local microcirculation of femoral head,as well as to inhibit the osteoclast activity,promote the osteoblast differentiation and maturation in vitro and enhance bone density. Key words: Steroid-induced femoral head necrosis; Epimedium; Blood rheology; Bone density