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The Correlation of Inflammation, Tryptophan-kynurenine Pathway, and Suicide Risk in Adolescent Depression

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Specialties Pediatrics
Psychiatry
Date 2024 Sep 17
PMID 39287643
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Abstract

Accumulating evidence suggests a role for the tryptophan-kynurenine pathway (TKP) in the psychopathology of major depressive disorder (MDD). Abnormal inflammatory profile and production of TKP neurotoxic metabolites appear more pronounced in MDD with suicidality. Progress in understanding the neurobiology of MDD in adolescents lags significantly behind that in adults due to limited empirical evidence. Aims of this study was to investigate the association between inflammation, TKP, and suicidality in adolescent depression. Seventy-three adolescents with MDD were assessed for serum levels of interleukin (IL)-1β, IL-6, IL-18, IL-10, tumor necrosis factor-α (TNF-α), tryptophan (TRP), kynurenine (KYN), 3-hydroxykynurenine (3-HK), and kynurenine acid (KA). Correlations between cytokines and TKP measures were examined. Patients were divided into high- (n = 42) and non-high-suicide-risk groups (n = 31), and serum levels of cytokines and TKP metabolites were compared. Significant negative correlations were found between TRP and IL-8 (r =  - 0.27, P < 0.05) and IL-10 (r =  - 0.23, P < 0.05), while a significant positive correlation was observed between 3-HK and IL-8 (r = 0.39, P < 0.01) in depressed adolescents. The KYN/TPR (index of indoleamine 2,3-dioxygenase, IDO) was positively correlated with IL-1β (r = 0.34), IL-6 (r = 0.32), IL-10 (r = 0.38) and TNF-α (r = 0.35) levels (P < 0.01); and 3-HK/KYN (index of kynurenine3-monooxidase, KMO) was positively correlated with IL-8 level (r = 0.31, P < 0.01). Depressed adolescents at high suicide risk exhibited significantly higher levels of IL-1β (Z = 2.726, P < 0.05), IL-10 (Z = 2.444, P < 0.05), and TNF-α (Z = 2.167, P < 0.05) and lower levels of 3-HK (Z = 2.126, P < 0.05) compared to their non-high suicide risk counterparts. Our findings indicated that serum inflammatory cytokines were robustly associated with IDO and KMO activity, along with significantly decreased serum level of TRP, increased level of 3-HK, and higher suicide risk in adolescent depression.

References
1.
Barberio B, Zamani M, Black C, Savarino E, Ford A . Prevalence of symptoms of anxiety and depression in patients with inflammatory bowel disease: a systematic review and meta-analysis. Lancet Gastroenterol Hepatol. 2021; 6(5):359-370. DOI: 10.1016/S2468-1253(21)00014-5. View

2.
Maes M, Kubera M, Obuchowiczwa E, Goehler L, Brzeszcz J . Depression's multiple comorbidities explained by (neuro)inflammatory and oxidative & nitrosative stress pathways. Neuro Endocrinol Lett. 2011; 32(1):7-24. View

3.
Dowlati Y, Herrmann N, Swardfager W, Liu H, Sham L, Reim E . A meta-analysis of cytokines in major depression. Biol Psychiatry. 2009; 67(5):446-57. DOI: 10.1016/j.biopsych.2009.09.033. View

4.
Drevets W, Wittenberg G, Bullmore E, Manji H . Immune targets for therapeutic development in depression: towards precision medicine. Nat Rev Drug Discov. 2022; 21(3):224-244. PMC: 8763135. DOI: 10.1038/s41573-021-00368-1. View

5.
Lamers F, Milaneschi Y, Smit J, Schoevers R, Wittenberg G, Penninx B . Longitudinal Association Between Depression and Inflammatory Markers: Results From the Netherlands Study of Depression and Anxiety. Biol Psychiatry. 2019; 85(10):829-837. DOI: 10.1016/j.biopsych.2018.12.020. View