Comparative study of the proliferative ability of skeletal muscle satellite cells under microwave irradiation in fractures with titanium alloy internal fixation in rabbits

The aim of the present study was to investigate the proliferation of skeletal muscle satellite cells (MSCs) under different amounts of microwave irradiation in fractures with titanium alloy internal fixation. A total of 45 male New Zealand adult white rabbits were used to establish a femoral shaft fracture and titanium alloy internal fixation model. The rabbits were randomly divided into the control group (group A) and the experimental groups (groups B and C). For 15 days, groups B and C were exposed to microwave treatment (25 or 50 W, respectively) for 10 min per day. The quadriceps femoris muscle was used for the isolation and culture of MSCs in vitro. The cultured cells were identified using cellular immunohistochemical staining. Transmission electron microscopy was used to observe mitochondrial ultrastructure damage, MTT assays were used to detect cell viability and cell cycle phases were analyzed by flow cytometry. The results revealed that, following 48 or 72 h of culture, cell viability was significantly greater in group B compared with group A, and was significantly lower in group C compared with group A (P<0.05). Compared with group A, the percentage of the cell population in the G0/G1 phase in group B was significantly decreased (P<0.05) and the proportion in the S and G2/M phases was increased (P<0.05). These results were reversed in group C; the percentage of cells in the S and G2/M phases was significantly lower (P<0.05) and in the G0/G1 phase was significantly higher (P<0.05) than in group A. These results suggested that in the healing of fractures with titanium, the proliferation of MSCs is significantly affected by microwave radiation in a dose-dependent manner.