Figure 2: Effect of piceatannol on the invasion of AH109A hepatoma cells (A), reactive oxygen species- (ROS-) potentiated invasive activity and intracellular peroxide levels (B). (A) Piceatannol was dissolved in ethanol. The piceatannol solution was added to the culture medium at a final ethanol concentration of 0.2%. Piceatannol was suspended in a 0.3% carboxymethyl cellulose sodium salt (CMC) aqueous solution at concentrations of 0.25, 0.5, and 1 mg/mL. Piceatannol suspension or 0.3% CMC alone (vehicle control) (1 mL/100 g body weight) was intubated to male Donryu rats which had been fasted overnight, and blood was collected 2 h after oral administration. The invasive activity was determined by AH109A-M cell coculture method in vitro (A(a)) and ex vivo (A(b)). Each value represents the mean ± SEM of ten areas. Values not sharing a common letter are significantly different at . (B) AH109A cells were cultured for 4 h in the absence or presence of 10 μM piceatannol with or without 25 μM hydrogen peroxide (H2O2). AH109A cells were then washed once with 10% CS/MEM and seeded on the M-cell monolayer in 10% CS/MEM without piceatannol and ROS. After cultured for 24 h, invaded cells and colonies underneath M-cells were counted with a phase-contrast microscope. Each value represents the mean ± SEM of ten areas. Values not sharing a common letter are significantly different at (B(a)). To evaluate the effect of piceatannol on intracellular peroxide levels, AH109A cells were treated with 100 μM H2O2 as ROS source. After ROS treatment for 1 hour, DCFH-DA was added, incubated for 20 minutes, and analyzed with a flow cytometer. Basal and ROS-potentiated intracellular peroxide levels are indicated as solid and dotted lines, respectively. Data are from representative experiment repeated three times with similar results (B(b)).