Fig. 4: PCK2-derived glycolytic intermediates shuttle into serine/glycine biosynthesis and glyceroneogenesis.

a, b Incorporation of [U¹³C]-glutamine and [U¹³C]-lactate carbon into total intracellular serine pool (a; n = 3) and glycine pool (b; n = 6) in ECs in 5.5 versus 0 mM glucose. c, d Incorporation of [U¹³C]-glutamine and [U¹³C]-lactate carbon into total intracellular serine pool (c; n = 5) and glycine pool (d; n = 3) in control and PCK2^KD1 glucose-deprived ECs. e Intracellular NADPH levels and NADP⁺/NADPH ratio in control and PCK2^KD1 glucose-deprived ECs (n = 6). f Quantification of cellular ROS levels (measured as median CM-H₂DCF fluorescence levels) in control and PCK2^KD1 glucose-deprived ECs (n = 3). g Incorporation of [U¹³C]-glutamine and [U¹³C]-lactate carbon into total intracellular glycerol-3-phosphate pool in ECs in 5.5 versus 0 mM glucose (n = 3). h Incorporation of [U¹³C]-glutamine and [U¹³C]-lactate carbon into total intracellular glycerol-3-phosphate pool in control and PCK2^KD1 glucose-deprived ECs (n = 3). i, j Incorporation of [U¹³C]-glutamine and [U¹³C]-lactate carbon into fractional m + 3 intracellular glycerol-phosphatidylcholine pool (i) and glycerol-phosphatidylethanolamine pool (j) in control and PCK2^KD1 ECs in 5.5 versus 0 mM glucose (n = 3). k Phospholipidomic profile analysis showing the log₂ abundance of saturated, mono-, di- and poly-unsaturated glycerol-phosphatidylcholine (PC) phospholipid species in PCK2^KD1 glucose-deprived ECs (n = 4–5 HUVEC donors) relative to their respective wild type control glucose-deprived ECs. The numbers under the axes indicate the carbon length of the fatty acid within each group of unsaturation degree (zero to ≥ 4). Data are mean ± s.e.m. Statistics: two-tailed t-test with Welch’s correction (a–h); ANOVA (i, j); one-sample t and Wilcoxon test (k) *P < 0.05; **P < 0.01; ***P < 0.001; ****P < 0.0001. AU arbitrary units.