Chemical characterization of wound ointment (WO) and its effects on fracture repair: a rabbit model

Background Wound ointment (WO), a kind of Chinese medicine, can significantly promote fracture healing. The study aimed at analyzing the chemical composition and the effects of WO on fracture of rabbits and tried to explore the corresponding molecular mechanism in cytokine. Methods The qualitative and quantitative analysis of WO was conducted by liquid chromatography-mass spectrometry (LC-MS). Fifty-four Zealand mature male rabbits were randomly divided into 3 groups: Control group, Yunnan Baiyao (YB) group and WO group. All the rabbits suffered a fracture of right radius and were then stabilized with an external fixator. Treated with different methods, fracture healing was observed. The bone specimens were subjected to radiograph, immunohistochemistry (IHC) analysis, hematoxylin-eosin staining (HE), western blot and enzyme linked immunosorbent assay (ELISA). Results A total of 12 active compositions were detected by LC-MS. Radiographs showed a considerably better bone healing and remodeling of the fracture in WO group. HE experiments showed that a large number of osteoclasts appeared in the early stage when treated with WO. In immunohistochemistry (IHC), western blot and ELISA test, significant increases in vascular endothelial growth factor (VEGF) expression were observed in WO group compared with other two groups. Conclusions Wound ointment contained active compositions which efficiently promoted fracture healing through increasing the expression of VEGF. Trial Registration Not applicable.