Figure 2. Loss or inhibition of DPP4 moderately promotes death of senescent hVSMCs.

(A) Micrographs depicting bright-field images of hVSMCs transfected with siCtrl or siDPP4 and treated with DMSO, CoCl₂, or Doxo for 7 days. Original magnification, ×20. (B) Percentage of viable cells from conditions described in A. (C) Normalized caspase-3 and -7 activity levels for cells and conditions described in A. (D–F) hVSMCs treated simultaneously with DMSO or DPP4i and DMSO, CoCl₂, or Doxo for 7 days were visualized (D) and the percentage of viable cells (E), and normalized caspase-3 and -7 activity levels (F) were calculated. Original magnification, ×20. Data are represented as mean ± SD from n = 3 or indicated biological replicates. Significance was established using Student’s t test with Bonferroni’s correction. *P ≤ 0.05; **P ≤ 0.01; ***P ≤ 0.001.