Figure 3: Cardiac Nuclear HMGB1 Prevents Ang II–Induced DNA Damage and the DDR in Mice

(A, B) Representative images and analysis of immunostaining of γ-H2AX (green), α-actinin (red), and DAPI (blue) in saline- or Ang II–treated WT and HMGB1-Tg mice. The number of γ-H2AX–positive CMs per field was counted. Scale bars = 50 μm. n = 6 in WT saline group; n = 6 in WT Ang II group; n = 6 in HMGB1-Tg saline group; n = 4 in HMGB1-Tg Ang II group. (C, D) Representative images and analysis of Western blots of γ-H2AX and β-tubulin from hearts of WT and HMGB1-Tg mice following saline or Ang II infusion (n = 5 per group). (E, F) Representative images and analysis of immunostaining of p-ATM (red), α-actinin (green), and DAPI (blue) in saline- or Ang II–treated WT and HMGB1-Tg mice. The number of p-ATM–positive CMs per field was counted. Scale bars = 50 μm. n = 6 in WT saline group; n = 7 in WT Ang II group; n = 5 in HMGB1-Tg saline group; n = 6 in HMGB1-Tg Ang II group. (G, H) Representative images and analysis of Western blots of p-ATM and total ATM from hearts of WT and HMGB1-Tg mice following saline or Ang II infusion (n = 6 per group). Results are presented as the mean ± SE. ∗p < 0.05; ∗∗p < 0.01; ∗∗∗p < 0.001. DDR = deoxyribonucleic acid damage response; DNA = deoxyribonucleic acid; Other abbreviations as in Figures 1 and 2.