Figure 2: (a) Cell viability was evaluated in HUVECs upon treatment with 2a, 2b, and 2c at 0.10, 0.50, 1.0, 5.0 and 10 μM, or untreated (control, 0.1% DMSO) using MTS assay. (b) Cell proliferation was assessed by BrdU incorporation assay. Bars represent the percentage of proliferating cells when compared to control group, after incubation with anti-BrdU antibody by ELISA assay. (c) Apoptosis was assessed in HUVECs by TUNEL assay using 2a, 2b, and 2c at 0.1, 0.5, and 1 μM. Bars represent the percentage of apoptotic cells evaluated by the ratio between TUNEL-stained cells and DAPI-stained nuclei in every culture. Results are expressed as mean ± SEM of three independent experiments ( ). * versus control.