All authors declare that they have no potential conflicts of interest relating to the data presented in this report or its publication.
KYNURENINE METABOLITES AND INFLAMMATION MARKERS IN DEPRESSED PATIENTS TREATED WITH FLUOXETINE OR COUNSELLING
Article first published online: 6 NOV 2008
© 2008 The Authors. Journal compilation © 2008 Blackwell Publishing Asia Pty Ltd
Clinical and Experimental Pharmacology and Physiology
Volume 36, Issue 4, pages 425–435, April 2009
How to Cite
Mackay, G. M., Forrest, C. M., Christofides, J., Bridel, M. A., Mitchell, S., Cowlard, R., Stone, T. W. and Darlington, L. G. (2009), KYNURENINE METABOLITES AND INFLAMMATION MARKERS IN DEPRESSED PATIENTS TREATED WITH FLUOXETINE OR COUNSELLING. Clinical and Experimental Pharmacology and Physiology, 36: 425–435. doi: 10.1111/j.1440-1681.2008.05077.x
- Issue published online: 26 MAR 2009
- Article first published online: 6 NOV 2008
- Received 26 June 2008; revision 22 August 2008; accepted 28 August 2008.
- brain-derived neurotrophic factor;
- 1Depression could result from changes in tryptophan availability caused by activation of the kynurenine pathway as a result of inflammation. In the present study, we examined patients newly diagnosed with depression to determine whether kynurenines and related factors change in parallel with improvements in mood.
- 2Concentrations of 5-hydroxytryptamine (5-HT; serotonin), 5-hydroxyindoleacetic acid (5-HIAA), oxidized tryptophan metabolites, brain-derived neurotrophic factor (BDNF) and inflammatory mediators (interleukin (IL)-2, C-reactive protein (CRP), neopterin) were measured in peripheral blood during an 18 week period of treatment with fluoxetine, fluoxetine plus tri-iodothyronine (T3) or psychiatric counselling.
- 3The results showed significant improvements in mood, with reduced 5-HT concentrations in patients given fluoxetine and a rise in plasma tryptophan in patients given counselling or fluoxetine and T3. The addition of T3 to the fluoxetine regimen appeared to slow recovery from depression, although the use of T3 was associated with a fall in thyroxine concentrations. Changes in 5-HT concentrations did not correlate with psychiatric scores and were seen only in drug-treated groups, not those given counselling. There were no associated changes in absolute concentrations of kynurenines, BDNF, CRP, neopterin or IL-2. With fluoxetine treatment, there were correlations between the concentrations of kynurenine metabolites and the psychiatric rating scores, whereas no correlations were found with BDNF or inflammatory markers.
- 4It is concluded that depression scores are largely independent of inflammatory status, but kynurenine metabolism may be related to the degree of depression after fluoxetine treatment.