Fig. 5: Isoniazid (INH) and copper (Cu) induce apoptosis in HepG2 cells.
From: Synergistic toxicity with copper contributes to NAT2-associated isoniazid toxicity
a-d Examples of FACS dot plots constructed for HepG2 cells treated with INH (1000 µM) or Cu (500 µM) for 24 h or 48 h are shown in a and c, respectively. Summarized results of multiple experiments are presented in b and d (n = 3). Treatment with INH-Cu for 24 h strongly increased the percentage of annexin V-positive ATP7B KO cells, and a longer period of INH and Cu incubation (48 h) produced annexin V and 7-AAD double-positive cells. e Western blot analysis of apoptosis markers in HepG2 cells treated with INH or Cu for 24 h. Summarized results of multiple experiments are presented in the lower panels (n = 3). f Results of an apoptotic DNA fragmentation assay. Increased DNA fragmentation was noted in ATP7B KO cells treated with Cu alone or INH-Cu. Identical results were obtained in four independent experiments. Bar graph data are shown as the mean ± SEM. *P < 0.05, **P < 0.01, ***P < 0.001 by multiple t tests with FDR correction. FCCP (25 µM) and cisplatin (40 µM) were used as positive controls.
