Vitamin C-induced metabolic alterations in MCF7 cells.
(a) Metabolic alterations in glycolysis and the TCA cycle induced by vitamin C. MCF7 cells were incubated in DMEM without or with vitamin C and metabolites levels were measured using CE-TOSMS. Colors of metabolites on heatmap indicate significant differences (red, upregulated; green, downregulated). Bar graphs indicate fold changes relative to control sample (None). (b) Effects of vitamin C on levels of AMP, ADP, ATP, GMP, GDP, GTP and adenylate energy charge. Bar graphs indicate fold changes relative to control sample (None). Adenylate energy charge calculation: (ATP + 0.5 × ADP)/(ATP + ADP + AMP). (c) Effects of vitamin C on levels of GSH and GSSG and GSH:GSSG ratio. Bar graphs show relative metabolite levels compared to control (None). Data are presented as means ± SD of triplicate experiments, *P < 0.05, **P < 0.01. ND, not detected.