Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2019 Feb 28;17(1):34-42.
doi: 10.9758/cpn.2019.17.1.34.

Values of Cytokines and Tryptophan Metabolites over a 12 Weeks Time Course in Patients with Depression and Somatoform Disorder

Daniela Krause  1 , Verena B Kirnich  2 , Theresa M Stapf  2 , Anika Hennings  3 , Sabine Riemer  3 , Michael Riedel  2 , Ralf Schmidmaier  4 , Francisco Pedrosa Gil  5 , Winfried Rief  3 , Markus J Schwarz  2
Affiliations

Values of Cytokines and Tryptophan Metabolites over a 12 Weeks Time Course in Patients with Depression and Somatoform Disorder

Daniela Krause et al. Clin Psychopharmacol Neurosci. .

Abstract

Objective: Previous studies have suggested alterations in the kynurenine pathway as a major link between cytokine and neurotransmitter abnormalities in psychiatric disorders. Most of these studies used a cross-sectional case-control study design. However, knowledge is still lacking regarding the stability over time of kynurenine pathway metabolites and the functionally related cytokines. Therefore, we studied the stability of cytokines and tryptophan (TRP) parameters over a period of 12 weeks.

Methods: A total of 117 participants-39 with major depression, 27 with somatoform disorder, and 51 healthy controls were enrolled. Four evaluations, including blood withdrawal and psychometric testing, were performed over a period of 12 weeks. We used ELISA to measure interleukin (IL)-6, IL-1 receptor antagonist (RA) and tumor necrosis factor α (TNF α). High-performance liquid chromatography was used to analyze neurotransmitter variables, i.e. TRP, 5-hydroxyindoleacetic acid (5-HIAA), kynurenine (KYN), 3-OH-kynurenine (3-HK), and kynurenic acid (KYNA).

Results: We found no significant fluctuations of TRP, its metabolites (5-HIAA, KYN, KYNA, and 3-HK), or the cytokines (IL-1RA, IL-6, and TNF α) in any of the groups over the 12 weeks.

Conclusion: To our knowledge, this is the first longitudinal study performed in psychiatric patients to verify the stability and consequently the reliability of the biological parameters we investigated. Our data indicate that TRP metabolites and cytokines are reliable biological parameters in psychiatric research because they do not fluctuate significantly over time.

Keywords: Cytokines; Depression; Kynurenic acid; Kynurenine; Somatoform disorders; Tryptophan.

PubMed Disclaimer

References

    1. Dantzer R, Bluthé RM, Castanon N, Kelley KW, Konsman JP, Laye S, et al. Cytokines, sickness behavior, and depression. In: Robert A, editor. Psychoneuroimmunology. 4th ed. Burlington: Academic Press; 2007. pp. 281–318. - DOI
    1. Leonard BE. The concept of depression as a dysfunction of the immune system. Curr Immunol Rev. 2010;6:205–212. doi: 10.2174/157339510791823835. - DOI - PMC - PubMed
    1. Dowlati Y, Herrmann N, Swardfager W, Liu H, Sham L, Reim EK, et al. A meta-analysis of cytokines in major depression. Biol Psychiatry. 2010;67:446–457. doi: 10.1016/j.biopsych.2009.09.033. - DOI - PubMed
    1. Howren MB, Lamkin DM, Suls J. Associations of depression with C-reactive protein, IL-1, and IL-6: a meta-analysis. Psychosom Med. 2009;71:171–186. doi: 10.1097/PSY.0b013e3181907c1b. - DOI - PubMed
    1. Capuron L, Ravaud A, Neveu PJ, Miller AH, Maes M, Dantzer R. Association between decreased serum tryptophan concentrations and depressive symptoms in cancer patients undergoing cytokine therapy. Mol Psychiatry. 2002;7:468–473. doi: 10.1038/sj.mp.4000995. - DOI - PubMed