[Effect of total flavone of Epimedium on expression of bone OPG, OPGL mRNA in ovariectomized rats].

Objective: To investigate the molecular mechanism of TFE (total flavone of epimedium) in the treatment of osteoporosis, and then provide experimental evidence for modernization and further development of TFE as an traditional Chinese medicine.

Methods: Sixty healthy female SD rats with aged 4 months were randomly divided into three groups (including control group in which rats received sham surgery, OVX group in which ovariectomized rats didn't give any medicine after the removal of ovaries and TFE group in which ovariectomized rats administrated TFE), 20 rats in each group. Compared bone mineral density (BMD) between before operation and at 4th week after operation in order to verify the establishment of osteoporotic model (criteria: BMD decreased more than 20% at 4th week after operation). The rats in TEF group were administrated total flavone of epimedium(concentration 30 mg/ml, 10 ml/kg, qd) orally for 4 weeks. After this, killed rats to harvest the lower part of the femur and detected BMD again. Applying the reverse transcriptase-polymerase chain reaction technique (RT-PCR) to detect expression of OPG, OPGL mRNA in bone tissue.

Results: (1) At 4th week after ovariectomy, the mean BMD of lumbar vertebra in TFE group fell to (0.084 +/- 0.020) g/cm2. Administrated with TFE for 4 weeks,the BMD increased to (0.112 +/- 0.009) g/cm2. There was significant improvement compare with the OVX group (P < 0.05). (2) Compared between OVX group and TFE group, The OPG mRNA expression of TFE group obviously enhanced. There was significant difference in statistics (P < 0.05). However,the promotion for OPGL mRNA expression were detected between OVX group and TFE group,there was no significant difference in statistics (P > 0.05).

Conclusion: This study showed that TFE could inhibit differentiation and maturation of osteoclast through enhancing OPG mRNA expression, accordingly,to treat osteoporosis.