Effects of the combined extracts of Herba Epimedii and Fructus Ligustri Lucidi on bone mineral content and bone turnover in osteoporotic rats

BACKGROUND The decoction combination of Herba Epimedii and Fructus Ligustri Lucidi has been used to treat osteoporosis for almost 50 years by practitioners of traditional Chinese medicine. However, it is unclear what specific effects this combination of herbs has on the skeleton. The aim of this study was to assess the effects of the combined extracts from Herba Epimedii and Fructus Ligustri Lucidi on the bone turnover and bone mineral content in a rat model of osteoporosis induced by retinoic acid. METHODS Fifty male Wistar rats were randomly assigned to the normal control group, osteoporosis model group, or treatment groups in which osteoporosis was induced and then the combined extracts of Herba Epimedii and Fructus Ligustri Lucidi were administered at 50, 100, or 200 mg/kg/day for 3 weeks via oral gavage. The rat osteoporosis model was induced by intragastric administration of 70 mg/kg/day of retinoic acid for 2 weeks. Bone turnover markers, bone biomechanical properties, and the calcium and phosphorus content of the right tibia and serum were measured. RESULTS The retinoic acid administration decreased the bone mass and the contents of calcium and phosphorus in the bone mineral, weakened the biomechanical properties, and increased bone turnover by stimulating bone resorption and collagen metabolism. Treatment with the combined extracts of Herba Epimedii and Fructus Ligustri Lucidi significantly mitigated the effects of osteoporosis on the rats by decreasing bone metabolism, improving the bone mineral content, and increasing the biomechanical properties. CONCLUSIONS The results of this study highlight the anti-osteoporosis effects of the combined extracts of Herba Epimedii and Fructus Ligustri Lucidi. These findings may contribute to the development of natural anti-osteoporosis herbal medicines.