Figure 4 | Scientific Reports

Figure 4

From: LC–MS/MS-based quantification of tryptophan, kynurenine, and kynurenic acid in human placental, fetal membranes, and umbilical cord samples

Figure 4

Kynurenine/tryptophan ratio (A), kynurenic acid/kynurenine ratio (B), and kynurenic acid/tryptophan ratio (C) in maternal placenta (MP), umbilical cord (UC) and fetal membrane (FM). Data are presented as a mean ± SEM, a number of subjects = 9 per group. *p < 0.05, ***p < 0.001 versus UC/FM. FM-fetal membrane, KYN-kynurenine, KYNA-kynurenic acid, MP-maternal placenta, TRP-tryptophan, UC-umbilical cord. A nonparametric Kruskal–Wallis test indicated a statistical difference in KYN/TRP ratio between at least two tissues (p = 0.001). Dunn’s multiple comparisons test showed a higher KYN/TRP ratio in MP versus UC (p < 0.001). Analysis of one-way ANOVA revealed a statistically significant difference in KYNA/KYN ratio between at least two tissues (p = 0.001). Tukey’s multiple comparisons test revealed that the KYNA/KYN ratio was significantly higher in UC versus MP (p < 0.001) and significantly higher in UC versus FM (p < 0.05). A nonparametric Kruskal–Wallis test showed a statistical difference in KYNA/TRP ratio between at least two tissues (p = 0.049). Dunn’s multiple comparisons test evidenced a higher KYNA/TRP ratio in FM (p < 0.05) than in MP.

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