Fig. 7

ABT-888 inhibits tachypacing-induced oxidative stress in HL-1 cardiomyocytes. HL-1 cardiomyocytes were pretreated with ABT-888 (40 µM) or vehicle DMSO (CTL) 12 h before tachypacing (TP). a, b Representative Western blot of protein carbonyl oxidation levels by DNP antibody staining and quantified data from n = 5 independent experiments for DMSO NP and TP, n = 3 independent experiments for ABT-888 NP and TP. ^*P < 0.05 vs. nonpaced (NP) DMSO. c, d Representative immunofluorescence staining of oxidative DNA damage marker 8-oxoguine (8-OxoG). n = 11 images from over 1000 cardiomyocytes. ^**P < 0.01 vs. NP CTL, ^##P < 0.01 vs. CTL TP. e, f Representative immunofluorescence staining of DNA damage marker γH2Ax and quantified data from n = 19 images for DMSO NP and ABT-888 NP; n = 18 images for DMSO TP, n = 11 for ABT-888 TP from over 200 cardiomyocytes. **P < 0.01 vs NP CTL, ^##P < 0.01 vs CTL TP. Scalebar is 15 µm. Data are all expressed as mean ± s.e.m. Individual group mean differences were evaluated with the two-tailed Student’s t test