Figure 3.

Reactive Oxygen Species Production, DNA Damage, and Iron Uptake

(A-C) Hydrogen peroxide levels measured by ROS-Glo assay (luminescence) in hiPSC-CMs after doxorubicin treatments (24 hours). (D) Representative images for γH2AX immunofluorescent staining in hiPSC-CMs after treatments with doxorubicin (24 hours, 1 and 3 μM). (E) Quantification of DNA damage on the basis of γH2AX staining in hiPSC-CMs using flow cytometry (ISO, n = 5; PRDM2-KO, n = 5; and MLH1-KO, n = 5). (F) Effect of HFE knockout on hiPSC-CM iron uptake (ISO, n = 6; and HFE-KO, n = 6) measured using calcein staining. Error bars represent ±SEM. n = full independent experimental replicates. ∗P < 0.05, ∗∗P ≤ 0.01, ∗∗∗P < 0.001, and ∗∗∗∗P < 0.0001 by Mann-Whitney U test (A-C) and 2-way analysis of variance (E and F). DAPI = 4′,6-diamidino-2-phenylindole; IC₅₀ = half maximal inhibitory concentration; other abbreviations as in Figure 2.