Objective: To study the influence of Tanshinone II A on the proliferation and migration of rabbit vascular smooth muscle cell in vitro and to primarily probe into the mechanism of how Tanshinone II A works.
Methods: Rabbit aortic artery was chosen for primary culture of vascular smooth muscle cells (VSMC), which were used and divided into control and Tanshinone II A groups with different drug concentrations. After cells, according to the protocol, incubated with drug for 24 h, 48 h or 72 h respectively, MTT assay was used to study the effect of Tanshinone II A on the VSMC proliferation; sterile scraper and contrast phase microscope were used to measure the distance of VSMC migration; analyses of cell cycle and DNA content were performed by flow cytometry. Then after TRITC-phalloidin labeling for cytoskeleton filament (F-actin), the influence of Tanshinone II A on the cytoskeleton was revealed by laser confocal microscope.
Results: (1) At the same time point, Tanshinone II A inhibited the proliferation and migration of rabbit VSMCs in vitro significantly in a dose-dependent manner; (2) After 24 h, compared with control group Tanshinone II A increased the ratio of rabbit VSMCs in G0/G1 phase, and decreased DNA content significantly in a dose-dependent manner; (3) Tanshinone II A influenced rabbit VSMCs cytoskeleton filament, including relatively short filaments arranged within nonpolarized cells and no lamellipodial protrusions, while in control group formation of lamellipodial protrusions and actin filaments parallel to long axis were seen. CONCLUSION; Tanshinone II A can significantly inhibit the proliferation and migration of rabbit VSMCs in vitro, which may result from arresting rabbit VSMCs through the check point of cell cycle, accumulating them in G0/G1 phase, inducing cell apoptosis and influencing the cytoskeleton filament.