PT  - JOURNAL ARTICLE
AU  - Johan Söderlund
AU  - Sara K. Olsson
AU  - Martin Samuelsson
AU  - Lilian Walther-Jallow
AU  - Christian Johansson
AU  - Sophie Erhardt
AU  - Mikael Landén
AU  - Göran Engberg
TI  - Elevation of cerebrospinal fluid interleukin-1β in bipolar disorder
AID  - 10.1503/jpn.100080
DP  - 2011 Mar 01
TA  - Journal of Psychiatry and Neuroscience
PG  - 114--118
VI  - 36
IP  - 2
4099  - http://jpn.ca/content/36/2/114.short
4100  - http://jpn.ca/content/36/2/114.full
SO  - J Psychiatry Neurosci2011 Mar 01; 36
AB  - Background: In recent years, a role for the immune system in the pathogenesis of psychiatric diseases has gained increased attention. Although bipolar disorder appears to be associated with altered serum cytokine levels, a putative immunological contribution to its patho-physiology remains to be established. Hitherto, no direct analyses of cerebrospinal fluid (CSF) cytokines in patients with bipolar disorder have been performed.Methods: We analyzed CSF cytokine concentrations in euthymic patients with diagnosed bipolar disorder type I (n = 15) or type II (n = 15) and healthy volunteers (n = 30) using an immunoassay-based protein array multiplex system.Results: The mean interleukin (IL)-1β level (4.2 pg/mL, standard error of the mean [SEM] 0.5) was higher and the IL-6 level (1.5 pg/mL, SEM 0.2) was lower in euthymic bipolar patients than in healthy volunteers (0.8 pg/mL, SEM 0.04, and 2.6 pg/mL, SEM 0.2, respectively). Patients with 1 or more manic/hypomanic episodes during the last year showed significantly higher levels of IL-1β (6.2 pg/mL, SEM 0.8; n = 9) than patients without a recent manic/hypomanic episode (3.1 pg/mL, SEM 1.0; n = 10).Limitations: All patients were in an euthymic state at the time of sampling. Owing to the large variety of drugs prescribed to patients in the present study, influence of medication on the cytokine profile cannot be ruled out.Conclusion: Our findings show an altered brain cytokine profile associated with the manifestation of recent manic/hypomanic episodes in patients with bipolar disorder. Although the causality remains to be established, these findings may suggest a pathophysiological role for IL-1β in bipolar disorder.