BACKGROUND: Low dose of puerarin combined with estradiol shows similar effects to high dose of puerarin or estradiol on treatment of osteoporosis in rats.
OBJECTIVE: To search the optimal doses for estradiol and puerarin for treatment of typeⅠosteoporosis.
METHODS: Sixty-four healthy female rats were randomly divided into eight experimental groups (n = 8): sham-operated, ovariectomized, puerarin-50, estradiol-200, puerarin+estradiol-5, 50, 10, 150. All rats were subjected to ovariectomy except those in the sham-operated group. Rats in the puerarin-50 group were subcutaneously injected with 50 mk/kg puerarin, once a day. Rats in the estradiol-200 group were subcutaneously injected with 200 μg/kg estradiol, twice a week. Rats in the puerarin+ estradiol-5, 50, 10, 150 groups were subcutaneously injected with 25 mg/kg puerarin, once a day and simultaneously injected with 5, 50, 10, 150 μg/kg estradiol, twice a week.
RESULTS AND CONCLUSION: Compared with sham-operated group, bone mineral density, bone calcium, and bone phosphorous of rats were significantly lower in the ovariectomized group (P < 0.05), and bone tissue presented with the pathological change of osteoporosis. After treatment with puerarin and/or estradiol for 10 and 20 weeks, bone mineral density, bone calcium, and bone phosphorous levels were significantly increased (P < 0.05), and puerarin+estradiol-100 group acquired the most obvious curative effects on osteoporosis. The results showed that 25 mg/kg puerarin (once a day) and 100 μg/kg estradiol (twice a day) is the best dose for treatment of osteoporosis in ovariectomized rats.