Icariin promotes early and late stages of fracture healing in rats.

OBJECTIVES This study aims to evaluate the effects of locally applied icariin on bone fracture healing in femur fractured rat model. MATERIALS AND METHODS The study included 64 male Sprague-Dawley rats (mean age 6 months; weighing, 280-490 g) in eight main study groups. Fracture healing process and level were evaluated with radiography, histopathology and dual energy X-ray absorptiometry to investigate the effects of local administration of icariin at varying doses, which is an exogenous osteo-inductive substance. Activities of superoxide dismutase (SOD) and glutathione peroxidase (GPx) were measured in the peripheral blood in addition to glutathione (GSH) and myeloperoxidase (MPO) levels to investigate the effects of icariin on the oxidant-antioxidant systems. RESULTS Radiological bone mineral density measurements and histopathological findings revealed that icariin improved all these parameters in the two healing periods tested. Superoxide dismutase activity decreased in association with local icariin application to the fractured side whereas GPx and GSH increased and MPO remained unchanged. Icariin increased the GPx and GSH levels which are responsible from scavenging hydroxyl radical and hydrogen peroxide. CONCLUSION Locally administered icariin to the fracture accelerated bone healing by reducing the oxidative stress.