Table 2

Geometric means with 95% confidence intervals for kynurenine pathway metabolites and gene expression of associated enzymes in the VLPFC of controls and depressed individuals

Metabolite/enzyme	Control		Depressed		ANCOVA^*

	n	Mean (95% CI)	n	Mean (95% CI)	Statistic	p value^†	Adjusted p value^‡
TRP	35	914.8 (764.18–1095.1)	45	1050.67 (900.77–1225.53)	t₇₄ = 1.22	0.23	0.45
Kynurenine	35	40.91 (33.47–50.0)	45	39.7 (33.44–47.14)	t₇₄ = 0.24	0.81	0.89
Kynurenine:TRP	35	0.045 (0.04–0.05)	45	0.038 (0.034–0.042)	t₇₄ = 2.41	0.019	0.044
KYNA	36	1.73 (1.28–2.34)	45	1.45 (1.12–1.89)	t₇₅ = 0.9	0.37	0.50
3-HK	36	1.88 (1.45–2.44)	45	1.61 (1.28–2.02)	t₇₅ = 0.95	0.35	0.50
QUIN	35	1.59 (1.26–2.0)	45	1.11 (0.91–1.35)	t₇₄ = 2.46	0.016	0.044
IDO1	32	0.96 (0.7–1.32)	43	0.4 (0.31–0.52)	t₆₈ = 4.39	0.001	0.001
IDO2	30	0.84 (0.56–1.24)	26	0.4 (0.28–0.56)	t₅₉ = 2.95	0.005	0.018
TDO2	32	0.92 (0.66–1.30)	43	0.37 (0.28–0.49)	t₆₈ = 4.39	0.001	0.001
KAT II	32	0.95 (0.77–1.18)	42	0.85 (0.71–1.02)	t₆₇ = 0.84	0.41	0.50
KMO	32	0.97 (0.77–1.22)	43	0.86 (0.72–1.04)	t₆₈ = 0.82	0.41	0.50

3-HK = 3-hydroxykynurenine; ANCOVA = analysis of covariance; CI = confidence interval; IDO = indoleamine 2,3-dioxygenase; KAT II = kynurenine aminotransderase II; KMO = kynurenine 3-monooxygenase; KP = kynurenine pathway; KYNA = kynurenic acid; QUIN = quinolinic acid; TDO = tryptophan-2,3-dioxygenase; TRP = tryptophan; VLPFC = ventrolateral prefrontal cortex.
↵* Adjusted means were estimated by ANCOVA on log-transformed KP metabolites to test control v. depressed differences, adjusting for age, sex and postmortem interval.
↵† Significant levels for unadjusted values for multiple comparisons.
↵‡ Significant levesl for adjusted values for multiple comparisons using the Benjamini–Hochberg modification of the Bonferroni method.