Back to Search
Start Over
Kynurenine pathway metabolites are associated with hippocampal activity during autobiographical memory recall in patients with depression
- Source :
- Brain, Behavior, and Immunity. 56:335-342
- Publication Year :
- 2016
- Publisher :
- Elsevier BV, 2016.
-
Abstract
- Inflammation-related changes in the concentrations of inflammatory mediators such as c-reactive protein (CRP), interleukin 1β (IL-1), and IL-6 as well as kynurenine metabolites are associated with major depressive disorder (MDD) and affect depressive behavior, cognition, and hippocampal plasticity in animal models. We previously reported that the ratios of kynurenic acid (KynA) to the neurotoxic metabolites, 3-hydroxykynurenine (3HK) and quinolinic acid (QA), were positively correlated with hippocampal volume in depression. The hippocampus is critical for autobiographical memory (AM) recall which is impaired in MDD. Here we tested whether the ratios, KynA/3HK and KynA/QA were associated with AM recall performance as well as hippocampal activity during AM recall. Thirty-five unmedicated depressed participants and 25 healthy controls (HCs) underwent fMRI scanning while recalling emotionally-valenced AMs and provided serum samples for the quantification of kynurenine metabolites, CRP, and cytokines (IL-1 receptor antagonist - IL-1RA; IL-6, tumor necrosis factor alpha - TNF, interferon gamma -IFN-γ, IL-10). KynA/3HK and KynA/QA were lower in the MDD group relative to the HCs. The concentrations of the CRP and the cytokines did not differ significantly between the HCs and the MDD group. Depressed individuals recalled fewer specific AMs and displayed increased left hippocampal activity during the recall of positive and negative memories. KynA/3HK was inversely associated with left hippocampal activity during specific AM recall in the MDD group. Further, KynA/QA was positively correlated with percent negative specific memories recalled in the MDD group and showed a non-significant trend toward a positive correlation with percent positive specific memories recalled in HCs. In contrast, neither CRP nor the cytokines were significantly associated with AM recall or activity of the hippocampus during AM recall. Conceivably, an imbalance in levels of KynA versus QA-pathway metabolites may adversely impact the function of the hippocampus and AM recall, raising the possibility that kynurenine pathway may affect emotion-dependent memory within the context of depression.
- Subjects :
- Adult
Male
0301 basic medicine
medicine.medical_specialty
Kynurenine pathway
Memory, Episodic
Immunology
Hippocampus
Context (language use)
Hippocampal formation
Kynurenic Acid
Article
Young Adult
03 medical and health sciences
Behavioral Neuroscience
chemistry.chemical_compound
0302 clinical medicine
Internal medicine
mental disorders
medicine
Humans
Psychiatry
Kynurenine
Depressive Disorder, Major
Recall
Endocrine and Autonomic Systems
Middle Aged
Quinolinic Acid
medicine.disease
Magnetic Resonance Imaging
030104 developmental biology
Endocrinology
chemistry
Mental Recall
Major depressive disorder
Female
Psychology
030217 neurology & neurosurgery
Quinolinic acid
Subjects
Details
- ISSN :
- 08891591
- Volume :
- 56
- Database :
- OpenAIRE
- Journal :
- Brain, Behavior, and Immunity
- Accession number :
- edsair.doi.dedup.....7f43e28db843eca5cfdb9647088ec423