OBJECTIVETo observe the effect of phytoestrogen (PE) in preventing and treating osteoporosis in ovariectomized rats.

METHODSForty-five Wistar female rats, 3 months old, were randomly divided into the sham-operated group, the model group, low dose and high dose PE groups, and the positive control group, 9 in each group. All rats, except that those in the sham operated group were simutaneously operated, were ovariectomized. The medication started from the 31st days after operation by daily given saline per os to the sham-operated group and the model group, PE per os to the PE groups, and estradiol by intramuscular injection to the positive control group. The animals were sacrificed 90 days later, their sera were collected for determination of biochemical parameters, their right femoral bone was taken to detect the bone mineral density (BMD), left femoral bone to examine pathology of bone trabecula, and whole uterus was weighed to calculate the uterine index.

RESULTSPE could increase the BMD level, serum estradiol and inorganic phosphorus content, and uterine index, lower serum BGP, tartrate-resistant acid phosphatase (TRAP), alkaline phosphatuse (AKP) and interleukin-6 levels. Pathological examination showed that in the model group, the cortex of bone thinned, bone trabecula thinned also, with poor integrity, distorted, broken and decreased in size, while in the PE groups, the above-mentioned changes were significantly alleviated.

CONCLUSIONPE is effective in preventing and treating osteoporosis in ovariectomized rats.