Myogenic differentiation requires to be exactly explored for the effective treatment of fracture. The speed of healing is affected by skeletal muscle, linked to activation of specific myogenic transcription factors during the repair process. In previous study, we discovered that psoralen enhanced differentiation of osteoblast in primary mouse. In the current study, we show that psoralen stimulates myogenic differentiation through the secretion of factors to hone the quality of repair in fractured mice. 3-month old mice were treated with corn oil or psoralen followed by a tibial fracture surgery. Fractures were tested 7, 14, and 21 days respectively later by histology and images observation. Skeletal muscles including soleus muscle and posterior tibial muscle around the damaged bone were collected for quantitative real-time PCR, HE staining, as well as western blot. Daily treatment with psoralen at seven, fourteen days or twenty-one days improves protein or mRNA levels responsible for the whole myogenic differentiation process, makes the muscle fibers more tightly aligned, and promotes callus formation and development. This data shows that high levels of myogenic transcription factors in the process of fracture healing in mice foster the repair of damaged muscles, and indicates a pharmacological approach that targets myogenic differentiation to improve fracture repair. This also reflects the academic thought of "paying equal attention to both muscles and bones" in the prevention and treatment of fracture healing.

Keywords: Psoralen, Myogenic differentiation, Tibial fracture surgery, mRNA.

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