Figure 3

Immunofluorescent (IF) stains of DNA damaged marker (γ-H2AX) and inflammatory cell (CD68+) infiltration in LV myocardium at 72 h after IR procedure. A to E) IF microscopic findings (400×) of γ-H2AX+ cells (white arrows) in non-infarct area of LV myocardium. F) Comparison of number of γ-H2AX+ cells in non-infarct area among the five groups. p < 0.0001, * vs. other groups with different symbols (*, †, ‡). Scale bars in right lower corner represent 20 μm. G to K) IF Microscopic findings (200×) of CD68+ cells (white arrows) in infarct area. L) Comparison of number of CD68+ cells among the five groups. p < 0.0001, * vs. other groups with different symbols (*, †, ‡). Scale bars in right lower corner represent 50 μm. All statistical analyses were performed by one-way ANOVA, followed by Bonferroni multiple comparison post hoc test (n = 8). Symbols (*, †, ‡) indicate significance (at 0.05 level). WT-SC = wide type sham control; WT-IR = wide type + ischemia reperfusion (IR); DDP4^D-SC = dipeptidyl peptidase-IV (DPP4) deficiency sham control; DDP4^D-IR = DDP4^D + IR; WT-IR-Sita = wide type + IR + sitagliptin.