No detectable effects of acute tryptophan depletion on short-term immune system cytokine levels in healthy adults. (28th May 2019)

• Record Type: Journal Article
• Authors: Hildebrandt, Caroline S.; Helmbold, Katrin; Linden, Maike; Langen, Karl-Josef; Filss, C. P.; Runions, Kevin C.; Stewart, Richard M.; Rao, Pradeep; Moore, Julie K.; Mahfouda, Simone; Morandini, Hugo A. E.; Wong, Janice W. Y.; Rink, Lothar; Zepf, Florian D.
• Is Part Of: World journal of biological psychiatry. Volume 20:Number 5(2019)
• Page Start: 416
• Page End: 423
• Publication Date: 2019-05-28
• Subjects: Acute tryptophan depletion -- serotonin -- immunology -- cytokines -- TNF-α -- IL-1β -- IL-6; Biological psychiatry -- Periodicals; Biological Psychiatry -- Periodicals; 616.89
• DOI: 10.1080/15622975.2018.1428357
• Languages: English
• ISSNs: 1562-2975

Abstract

Abstract: Objectives: Recent research suggested an influence of diminished central nervous serotonin (5-HT) synthesis on the leptin axis via immunological mechanisms in healthy adult females. However, studies assessing immunological parameters in combination with dietary challenge techniques that impact brain 5-HT synthesis in humans are lacking. Methods: In the present trial, a pilot analysis was conducted on data obtained in healthy adult humans receiving either different dietary acute tryptophan depletion (ATD) challenge or tryptophan (TRP)-balanced control conditions (BAL) to study the effects of reduced central nervous 5-HT synthesis on serum tumor necrosis factor α (TNF-α), interleukin-1β (IL-1β) and IL-6 concentrations. The data of N = 35 healthy adults were analysed who were randomly subjected to one of the following two dietary conditions in a double-blind between-subject approach: (1) The Moja-De ATD challenge (ATD), or (2) TRP-balanced control condition for ATD Moja-De (BAL). Serum concentrations for the assessment of relevant parameters (TNF-α, IL-1β and IL-6) and relevant TRP-related characteristics after the respective challenge procedures were assessed at baseline (T0) and in hourly intervals after administration over a period of 6 h (T1–T6). Results: The ATD condition did not result in significant changes to cytokine concentrations for the entire study sample, or in male and female subgroups. Depletion of CNS 5-HT via dietary TRP depletion appears to have no statistically significant short-term impact on cytokine concentrations in healthy adults. Conclusions: Future research on immunological stressors in combination with challenge techniques will be of value in order to further disentangle the complex interplay between brain 5-HT synthesis and immunological pathways.