Figure 2

Effects of Exisulind on proliferation or apoptosis of VSMCs and ECs in vitro and in vivo.

(A) Morphologic changes of VSMCs when treated with each concentration of Exisulind for 24 hours. Scale bar = 100 μm. Exi = Exisulind. (B) Tryphan blue assay showed that Exisulind reduced the viability of VSMCs in a dose-dependent manner. *P = 0.04 vs. PDGF-treated group, **P < 0.01 vs. PDGF-treated group. However, Exisulind did not reduce the viability of ECs, even at relatively high concentration (250 μM). (C) Flow cytometry analysis shows that Exisulind increased apoptotic cell fractions in a dose-dependent manner in VSMCs. *P = 0.19 vs. vehicle group, **P < 0.01 vs. vehicle group. However, the apoptotic fraction for EC was not affected by Exisulind treatment. The data are presented as mean + SEM of four to ten independent experiments. (D) Cell cycle analysis shows that Exisulind blocked PDGF-induced cell-cycle progression of VSMCs to S phase in a dose-dependent manner. Black bar = G0/G1 phase, gray bar = G2 phase, white bar = S phase. *P < 0.01 vs. vehicle in terms of G1 phase. (E) Immunohistochemical staining for TUNEL or PCNA expressions in the carotid artery wall in the vehicle-treated group (left panel) and Exisulind-treated group (right panel). Exisulind treatment increased TUNEL-positive cells and decreased PCNA-positive cells in the vessels. Scale bar = 100 μm. Quantification graph of TUNEL- or PCNA- positive cells suggests that Exisulind increased apoptosis and decreased proliferation in VSMCs. *P < 0.01 vs. control group, **P < 0.01 vs. control group, Scale bar = 100 μm. (F) Scratch wound migration assay shows that Exisulind treatment significantly reduced VSMC migration. Scale bar = 100 μm. *P = 0.04 vs. PDGF group, **P = 0.02 vs. PDGF group.