Figure 2 of Mansoor, Mol Vis 2013; 19:25-38.

Figure 2. The effects of chrysene (Chry) treatment on caspase-3/7 activity in MIO-M1 cells. A: The MIO-M1 cells treated 24 h with 1,000 μM (***p<0.001), 500 μM (***p<0.001), and 300 μM (**p<0.01) chrysene showed significantly increased caspase-3/7 activities compared to dimethyl sulfoxide (DMSO)-equivalent-treated cells. The untreated cells, 100-μM-chrysene-treated cells, and equivalent-DMSO-treated cells showed similar levels of caspase-3/7 activity. B: Analyses of DNA fragmentation patterns for chrysene-treated MIO-M1 cells. After treatment with 100 μM chrysene (lane 2), the MIO-M1 cells showed DNA fragmentation at 200-base pair (bp) intervals compared to the untreated control cultures (lane 1) which is consistent with apoptosis. C: The protective effects of lipoic acid (LA) against chrysene induced caspase-3/7 activity in MIO-M1 cells. The MIO-M1 cells pretreated 6 h with 80 μM LA followed by the addition of 500 μM chrysene (500 μM +LA 80 μM) for 24 h showed lower caspase-3/7 activity levels compared to the cells treated with 500 μM chrysene alone (***p<0.001). The untreated cells, DMSO-equivalent-treated cells (DMSO 500 μM), and cells treated with 80 μM LA alone (LA 80 μM) showed low levels of caspase-3/7 activity. Assays were performed in triplicate and the experiments repeated three times. The DNA fragmentation analyses were repeated twice. Values are mean±standard error mean (SEM). M, marker; bp, base pair.