Figure 3. Metabolic alterations related to GSH metabolism and the γ-glutamyl cycle.

(a) Boxplots showing the altered metabolites. Boxes denote interquartile ranges, lines denote medians and whiskers denote the 10^th and 90^th percentiles. Metabolite relative abundance, expressed as ratio or log-transformed, is calculated by referring metabolite peak intensity to a constant concentration of internal standard per mg of tissue. Green: control (C); blue: oxidative stress (OS); red: phospholipidosis (P); purple: steatosis (S). *, q value < 0.05; **, q value < 0.01; ***, q value < 0.001 calculated using the Mann Whitney test corrected for multiple testing by using FDR. (b) The γ-glutamyl cycle, which accounts for GSH synthesis and recycling. Enzymes are denoted in italics. Square boxes denote transmembrane transporters. Aa: amino acid; Cys: cysteine; Cys-Gly: cysteinyl-glycine; DP: dipeptidase; GCL: glutamate cysteine ligase; γ-Glu-Aa: γ-glutamyl amino acid; GGT: γ-glutamyl transpeptidase; Glu: glutamate; Gly: glycine; GS: glutathione synthetase.