RESUMO
OBJECTIVE: To study the protective effect of the total isoflavones from Pueraria lobata (TIP) on secondary osteoporosis induced by dexamethasome (DXM). METHODS: Female SD rats, 4 month aged, were given intramuscularly with 1.5 mg/kg DXM twice once week. The treated groups were orally given TIP 100, 50 or 25 mg.kg-1.d-1 for 6 months. The whole body BMD and BMC were detected at 3 and 6 months. The biodynamics potency, density, ash weight and calcium content of femur were determined at 6 months. RESULTS: (1) At 3 and 6 months, BMDs in TIP 100 mg/kg group were increased by 3.4% and 8.4% than that in model group, BMC were increased by 7.0% and 9.1%, while in TIP 50 mg/kg group by 3.2%, 5.3% and 6.2%, 6.0%. (2) The Fmax and hardness in TIP 100 mg/kg group were enhanced by 10.3% and 10.5%, when in TIP 50 mg/kg group were enhanced by 3.5% and 7.1%. (3) TIP can increase wet and dry weight in slightly extent, but significantly increase wet density and dry density. (4) The ash weight and calcium content in femur were increased by 3.1% and 4.2% in TIP 100 mg/kg group, 4.3% and 6.4% in TIP 50 mg/kg group, while no change in TIP 25 mg/kg group. CONCLUSIONS: TIP can prevent secondary osteoporosis induced by DXM in rats.