siRNA-Nrf2 enhances triptolide-induced oxidative stress in HepG2 cells.

<p>HepG2 cells transfected with siRNA-control or siRNA-Nrf2 were treated with triptolide at various concentrations for 6 h. (A) Levels of intracellular GSH were measured. (B) The intracellular ROS levels were measured using the fluorescent probe DCFH-DA.The data are represented as the mean ± SD from three independent experiments. *<i>P</i><0.05, **<i>P</i><0.01 versus vehicle control; ^#<i>P</i><0.05, ^##<i>P</i><0.01 versus si-control cells treated with the same concentration of triptolide. Con: control (0.1% DMSO).