Low-intensity ultrasound to induce proliferation and collagen Ι expression of adipose-derived mesenchymal stem cells and fibroblast cells in co-culture

Abstract In tissue engineering, mechanical stimulates are required for creating the condition suitable for cell proliferation. This study examined low-intensity ultrasound to improve cells by effective mechanical interaction. A 40 kHz frequency ultrasound system was designed with an intensity of 0.12-0.35 W/cm2. Cells were sonicated with an optimum mechanical index. Mesenchymal stem cells and fibroblast cells were isolated from the subcutaneous adipose of guinea pigs. The proliferation of cells was measured with MTT assay in co-culture. Collagen I expression was quantified with a real-time polymerase chain reaction. The proliferation rate of mesenchymal stem cells increased in the 0.20 mechanical index by 0.64 ± 0.05 compared to the control group (0.26± 0.04). The expression level of collagen I was achieved as 4.74 ± 0.05 in mesenchymal stem cells and 11.01 ± 0.05 in fibroblast cells. These results indicate that the mechanical index parameter 0.20 has promoted collagen I expression and cell proliferation.