Figure 5.

P53 is involved in UNC5B induced endothelial cell premature senescence. (a, b) Young control and UNC5B-overexpressing HUVECs or replicative senescent HUVECs transfection with siRNA for three days were subjected to immunofluorescence of γ-H2AX foci (red). Cells with no less than 20 foci were scored as γ-H2AX-positive cells. Approximately 150 cells were analyzed per experiment. Scale bar, 10 μm. (c) Replicative senescent cells were transfected with siRNA for three days. The protein expression levels of UNC5B, P21, and P53 of the cells were analyzed by western blot. (d) After young cells infection with lentiviral vectors, PFTα or DMSO was added and maintained 5 μmol/L in both control and UNC5B-overexpressing cells throughout the experiment. The cells were then lysed for western blot analysis. (e) The proliferative potential of these cells treated with or without PFTα was detected by Edu incorporation assay. Scale bar, 50 μm. Quantitative data are presented as mean ± SEM of three or more independent experiments. ^∗ means P < 0.05, ^∗∗ means P < 0.01.