Figure 9.

Involvement of ROS-induced apoptosis in CHOP-dependent exacerbation of DSS-induced colitis. DSS was administered to CHOP-null mice (Chop^−/−) and WT mice, as described in the legend of Figure 1. Sections of colonic tissues were prepared and subjected to TUNEL assay and DAPI staining. A: The right panel in each column is a ×3 magnified image of the boxed area defined in the left panel. HCT-15 cells were transfected with siRNA for CHOP (siCHOP) or nonsilencing (ns) siRNA and were incubated with indicated concentrations of menadione for 12 hours. B: Relative mRNA expression of the CHOP was monitored as described in the legend of Figure 2A. C: Cell viability was determined using the MTT method. D: The intracellular antioxidant activity was measured as described in the Materials and Methods. Values shown are mean ± SEM (n = 3). ** or ^##P < 0.01; n.s., not significant.