Figure 3. Effect of FBS deprivation on young and senescent HUVECs. yHUVECs and sHUVECs were cultured for 48 (48h) or 72 (72h) hours with or without (w/o) FBS. Annexin V positivity and casp-3 activation were analyzed by flow cytometry. (A) Percentage of annexin V-positive cells (left) and ratio of annexin V-positive apoptotic cells among yHUVECs and sHUVECs w/o FBS to their control (with FBS) (right). (B) Percentage of cells with active casp-3 (left); ratio of yHUVECs or sHUVECs w/o FBS with activated casp-3 to control cells (right). (C) Bcl-xL mRNA fold change in yHUVECs and sHUVECs. (D) Western blot and densitometric analysis of Survivin expression in yHUVECs and sHUVECs. (E) Western blot and densitometric analysis of Bcl-2 in yHUVECs and sHUVECs. (F) Percentage of HUVECs showing mPTP opening. Protein expression values are reported as Bcl-2 and Survivin fold change in sHUVECs vs yHUVECs. Data are normalized to β-actin protein. Data are mean ± SD of three independent experiments. * t -test p < 0.05, ** t-test p < 0.01, *** t-test p < 0.001.