Effect of antler extract on corticosteroid-induced avascular necrosis of the femoral head in rats

Ethnopharmacological relevanceDeer antler, traditionally used as a tonic and valuable drug in oriental medicine, has been considered to possess bone-strengthening activity and effectively used in bone diseases therapy.Aim of the studyThe present study was designed to investigate therapeutic effect of antler extract on avascular necrosis of the femoral head (ANFH) induced by corticosteroids in rats.Materials and methodsRats were intragluteally injected with dexamethasone at 50 mg/kg twice per week for 6 weeks to induce ANFH. Then the rats were treated with antler extract by oral gavage at 200 mg/kg, 400 mg/kg and 800 mg/kg once per day for 60 days. The concentration of hydroxyproline and hexosamine in serum was measured and the ultrastructure of femoral head was examined. In vitro, effect of the drug-containing serum of antler extract on proliferation and differentiation of primary osteoblasts were investigated by MIT assay, ALP activity assay and cell cycle analysis.ResultsAfter treatment with antler extract, the degree of necrosis induced by dexamethasone was significantly reduced, hydroxyproline was significantly decreased, and hexosamine and the ratio of hexosamine/hydroxyproline were significantly increased. The drug-containing serum of antler extract promotes osteoblastic proliferation through regulation of cell cycle progression.ConclusionsThe results suggest that antler extract has a positive curative effect on ANFH by promoting osteoblastic proliferation.