title: Increased cerebrospinal fluid interleukin-6 levels in patients with schizophrenia and those with major depressive disorder.
abstract: Elevated peripheral levels of interleukin-6 (IL-6) are common findings in schizophrenia and depression. However, previous studies that measured cerebrospinal fluid (CSF) IL-6 levels in these disorders reported controversial results. The present study examined whether CSF IL-6 levels are altered in patients with schizophrenia and those with depression. Lumbar punctures were performed in 32 patients with schizophrenia, 30 with major depressive disorder (MDD), and 35 healthy controls. Serum samples were simultaneously collected from all subjects in the patient groups and from 32 of the control group. CSF and serum IL-6 levels were determined by enzyme-linked immunosorbent assay. Both the patients with schizophrenia and MDD had significantly higher CSF IL-6 levels compared to the controls (schizophrenia: P = 0.0027; MDD: P = 0.012). IL-6 levels were significantly higher in the CSF than in the serum. No significant correlation was observed between CSF and serum IL-6 levels. The present findings suggest that IL-6 of central origin is associated with the pathophysiology of schizophrenia and MDD, although confounding effect of smoking status can not be entirely excluded.
authors.affiliation: Department of Mental Disorder Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry, 4-1-1, Ogawahigashi, Kodaira, Tokyo 187-8502, Japan; Department of Psychiatry, Shinshu University School of Medicine, Matsumoto 390-8621, Japan.
authors.forename: Daimei
authors.initials: D
authors.lastname: Sasayama
authors.forename: Kotaro
authors.initials: K
authors.lastname: Hattori
authors.forename: Chisato
authors.initials: C
authors.lastname: Wakabayashi
authors.forename: Toshiya
authors.initials: T
authors.lastname: Teraishi
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Hori
authors.forename: Miho
authors.initials: M
authors.lastname: Ota
authors.forename: Sumiko
authors.initials: S
authors.lastname: Yoshida
authors.forename: Kunimasa
authors.initials: K
authors.lastname: Arima
authors.forename: Teruhiko
authors.initials: T
authors.lastname: Higuchi
authors.forename: Naoji
authors.initials: N
authors.lastname: Amano
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kunugi
mesh_terms: D000328:Adult; D003865:Major Depressive Disorder / Q000097:blood / Q000134:cerebrospinal fluid* / Q000150:complications*; D005260:Female; D006801:Humans; D015850:Interleukin-6 / Q000097:blood / Q000134:cerebrospinal fluid*; D008297:Male; D008875:Middle Aged; D012559:Schizophrenia / Q000097:blood / Q000134:cerebrospinal fluid* / Q000150:complications*; D018709:Statistics, Nonparametric
chemical_list: D015850:Interleukin-6