Figure 7.

Post-dissection, ex vivo liver metabolism changes 13C isotopologue abundances and fractional enrichments. (A) Schematics of the [U–¹³C]-glucose tracing experiment (left) and the ¹³C incorporation into TCA cycle intermediates from glycolytically produced pyruvate (right). Pyruvate oxidation by pyruvate dehydrogenase (PDH) results in m+2 TCA cycle isotopologue enrichments, and pyruvate carboxylation by pyruvate carboxylase (PC) results in m+3 TCA cycle isotopologue enrichments. (B–G) Line graphs showing the isotopologue % enrichments (left y-axis) overlaying the corresponding bar graphs depicting the lactate (B), citrate (C), α-ketoglutarate (D), succinate (E), and fumarate (F), and malate (G) fold changes by delayed freezing time-point compared to time zero. Data are presented as the mean ± SEM. P-values were calculated by one-way ANOVA with the post-hoc Holm-Sidak multiple comparison test (n = 8 biological replicates). ^†p < 0.1, ∗p < 0.05, ∗∗p < 0.01, ∗∗∗p < 0.001 (% Enrichment); ^$$p < 0.01, ^$$$p < 0.001 (Fold change); Related to Table S7.