Fig. 6.

Glycine-based treatment induces de novo GSH synthesis in macrophages. (A) Schematic representation of labeling de novo synthesized GSH from ¹³C₅-labeled glutamine in BMDMs. BMDMs were treated with glycine-depleted media for 18 h, then incubated for 5 h with glycine-depleted media supplemented with ¹³C₅-labeled glutamine (1 mM) and water control (cont.), glycine (Gly, 1 mM), or DT-109 (1 mM). Isotopologue distribution of indicated cellular metabolites as determined by LC-MS/MS (n = 5–6): (B) glutamine, (C) glutamate, (D) γ-glutamylcysteine, (E) M+5 isotopologue of γ-glutamylcysteine, (F) GSH, and (G) M+5 isotopologue of GSH. Metabolite peak area was normalized to total measurable ions in the sample. Data are presented as mean ± SEM. Statistical differences were compared using one-way ANOVA with Tukey's post hoc analysis.