Figure 2.

Huh7 cells expressing HCV Core and NS5A are protected against apoptosis induced by oxidative stress. Apoptosis was determined by measuring caspase 3 activity in Huh7 cells expressing (A) empty vector, (B) Core, (C) NS3/4A and (D) NS5A after menadione treatment (50 μmol/L). In some experiments, cells were pre-treated with 5 mmol/L N-acetyl-l-cysteine (NAC) 30 min prior to addition of menadione. Cells were plated in 6-well plates and 24 h post-seeding treated with menadione for 6 h. Caspase 3 activity was determined as described in Materials and Methods and represented as fold change in arbitrary units of fluorescence (AUF). The graphs depict means ± SD of three independent experiments. A t-test was performed to compare the means and the asterisks represent the p value *** <0.0009, ** ˂0.002 and * ˂0.02. n.s = non-significant, (p values > 0.05 are considered not statistically significant).