Protective effect of low-intensity pulsed ultrasound on hPDLSCs injured by high glucose / 国际生物医学工程杂志

ABSTRACT

Objective:To investigate the protective effect and mechanism of low-intensity pulsed ultrasound on human periodontal ligament stem cells (hPDLSCs) injured by high glucose.Methods:hPDLSCs were cultured in vitro and randomly divided into normal control group, high glucose model group and three low intensity pulsed ultrasound groups (30, 60, 90 mW/cm 2). Cells in the high glucose model group and three low intensity pulsed ultrasound groups were treated with high glucose medium (glucose 40 mmol/L) for 48 h to establish high glucose model. Cells in the normal control group were treated with normal medium (glucose 11 mmol/L). After modeling, three low intensity pulsed ultrasound groups were treated with low-frequency pulse for 20 min each day for 7 days at a dose of 30, 60 and 90 mW/cm 2 respectively. After 7 days, the proliferation ability of each group was determined by MTT assay. The changes of cell cycle and apoptosis were detected by flow cytometry. The level of Caspase-3, Caspase-6, and Caspase-9 was detected by colorimetry. The levels of Wnt1, Wnt10b and β-catenin genes and proteins were detected by reverse transcription PCR and Western Blot respectively. Results:Compared with the hPDLSCs in the normal control group, the hPDLSCs in the high glucose model group have the following changes except for the cell cycles (all P>0.05), i.e. the activity of the cells was decreased and the apoptosis was increased (all P<0.05), the activities of Caspase-3, Caspase-6, and Caspase-9 were increased (all P<0.05), and the expressions of Wnt1, Wnt10b and β-catenin genes and proteins were decreased (all P<0.05). Compared with the hPDLSCs in the high glucose model group, the hPDLSCs in low-intensity pulsed ultrasound groups have the following changes expect for the cell cycles (all P>0.05), i.e. cell viabilities were increased (all P<0.05), proliferation abilities were increased (all P<0.05), apoptosis rates were decreased (all P<0.05), the activities of Caspase-3, Caspase-6, Caspase-9 were decreased (all P<0.05), and the expressions of Wnt1, Wnt10b and β-catenin genes and proteins were up-regulated ( P<0.05). Among the three low-intensity pulsed ultrasound groups, when the ultrasonic intensity is 90 mW/cm 2, the above-mentioned index changes most obviously (all P<0.05). Conclusions:Low-intensity pulsed ultrasound can significantly alleviate the hPDLSCs damage induced by high glucose, which may be achieved by reducing the activities of Caspase-3, Caspase-6 and Caspase-9, and up-regulating the expression of Wnt1, Wnt10b and β-catenin.