Kynurenic acid and psychotic symptoms and personality traits in twins with psychiatric morbidity.

Abstract

Increased cytokines and kynurenic acid (KYNA) levels in cerebrospinal fluid (CSF) have been reported in patients with schizophrenia and bipolar disorder. The aim of the present study was to investigate cytokines and kynurenines in the CSF of twin pairs discordant for schizophrenia or bipolar disorder and to study these CSF markers in relation to psychotic symptoms and personality traits. CSF levels of tryptophan (TRP), KYNA, quinolinic acid (QUIN), interleukin (IL)-6, IL-8 and tumor necrosis factor-alpha (TNF-α) were analyzed in 23 twins with schizophrenia or bipolar disorder, and in their not affected co-twins. Ratings of psychotic symptoms and personality traits were made using the Scales for Assessment of Negative and Positive symptoms, the Structured Clinical Interview for DSM-IV - Axis II Disorders, and the Schizotypal Personality Questionnaire - Brief. A total score for psychotic symptoms and personality traits was constructed for analysis. CSF KYNA was associated with the score for psychotic symptom and personality traits. TNF-α and IL-8 were associated, and the intra-pair differences scores of TNF-α and IL-8 were highly correlated. Intraclass correlations indicated genetic influences on CSF KYNA, TRP, IL-8 and TNF-α. The association between KYNA and psychotic symptoms further supports a role of KYNA in psychotic disorders.

• Authors: Magdalena E Kegel, Viktoria Johansson, Lennart Wetterberg, Maria Bhat, Lilly Schwieler, Tyrone D Cannon, Ina Schuppe-Koistinen, Göran Engberg, Mikael Landén, Christina M Hultman, Sophie Erhardt
• Journal: Psychiatry research (Psychiatry Res) Vol. 247 Pg. 105-112 (Jan 2017) ISSN: 1872-7123 [Electronic] Ireland
• PMID: 27886578 (Publication Type: Journal Article, Twin Study)
• Copyright: Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Chemical References

• Interleukin-6
• Interleukin-8
• Tumor Necrosis Factor-alpha
• Tryptophan
• Quinolinic Acid
• Kynurenic Acid

Topics

• Bipolar Disorder (cerebrospinal fluid, psychology)
• Female
• Humans
• Interleukin-6 (cerebrospinal fluid)
• Interleukin-8 (cerebrospinal fluid)
• Kynurenic Acid (cerebrospinal fluid)
• Male
• Middle Aged
• Personality
• Psychotic Disorders (complications)
• Quinolinic Acid (cerebrospinal fluid)
• Schizophrenia (cerebrospinal fluid)
• Schizophrenic Psychology
• Tryptophan (cerebrospinal fluid)
• Tumor Necrosis Factor-alpha (cerebrospinal fluid)
• Twins (psychology)