OBJECTIVE: To investigate the effects of soybean isoflavones (SI) on expression levels of osteoprotegerin (OPG) and osteoprotegerin ligand (OPGL) mRNAs in bone tissues of ovariectomized rats, and to discuss the mechanism of soybean isoflavaones in preventing and treating postmenopausal osteoporosis (PMO).METHODS: Thirty adult SD rats were randomly divided into 3 groups: sham-operation group, untreated group and SI-treated group. The rats in the last two groups were bilaterally ovariectomized. The bone density of L(3) to L(6) vertebrae was detected after 12-week intervention. Total RNA was extracted from femur head and the expression levels of OPG and OPGL mRNAs were examined by real-time quantitative polymerase chain reaction.RESULTS: SI could increase the bone density of lumbar vertebrae in ovariectomized rats, up-regulate the expression level of OPG mRNA and down-regulate the ratio of OPGL mRNA/OPG mRNA, but exert no significant effect on the expression of OPGL mRNA.CONCLUSION: The therapeutic effects of SI on PMO may be related to regulating the expression levels of OPG and OPGL mRNAs, and the ratio of OPGL mRNA/OPG mRNA.
Animals Bone Density