Fig. (2) Effect of natural antioxidants on intracellular ROS levels in cultured endothelial cells. (A) Measurement of Intracellular ROS generation in cultured human ECs in the absence (CTRL) or presence of 25 µM caffeic acid, coumaric acid, chlorogenic acid and resveratrol. (B) Measurement of Intracellular ROS generation in cultured human ECs in the absence (CTRL) or presence of 25 µM caftaric acid and ferulic acid. Treatment-induced variation of fluorescence was kinetically measured every minute for 120 consecutive minutes as described in materials and methods. (Figure insets): Using as reference untreated cells, the overall anti- and pro-oxidant effect was extrapolate by comparison of the slope obtained from at least five kinetic measurements for each experimental condition. Data are expressed as percentage of control and represent the means ± SE of five different experiments. * significantly different from CTRL at P<0.05.