Handbook of Vitamin C Research

112Ana I. Haza, Almudena García and Paloma MoralesEffect of Vitamin C on NPIP and NDBA-Induced ROS ProductionFigure 16 shows the effect of vitamin C on NPIP and NDBA-induced ROS production inHepG2 and HL-60 cells, respectively. In our previous work, it was observed a significantincrease in ROS levels after treatment with 25 and 20 mM NPIP in HepG2 and HL-60 cells,respectively, whereas NDBA (2 mM) only induced ROS production in HL-60 cells [44, 45].For that reason we did not examine the effect of vitamin C on NDBA-induced ROSproduction in HepG2 cells. In the present chapter, it was not detected significant difference inintracellular ROS levels in both cell lines pre-treated with only vitamin C (5-50 M) for 1 h(Figure 16). In combined treatments, high ROS levels induced by NPIP were significantlyreduced at all concentration tested of vitamin C (5-50 M, 29-58% of reduction) in HepG2cells (Figure 16 A). Similarly, ROS levels induced by NPIP in HL-60 cells were significantlyreduced at all concentration tested of vitamin C (5-50 M, 51-60% of reduction) (Figure 16B), whereas only 10-50 M vitamin C partially eliminated intracellular ROS levels inducedby NDBA (9-19% of reduction) (Figure 16 C).Figure 16.Figure 16. Effect of vitamin C on ROS production in HepG2 (A) and HL-60 cells (B and C) in theabsence ( ) or presence ( ) of NPIP (25 and 20 mM, respectively) or NDBA (2 mM). DCFfluorescence was measured with a flow cytometer and expressed as % of control. Data are mean ± SD.Asterisks indicate significant difference from control ***p 0.001, ** p 0.01 and *p 0.05.