title: Serum brain-derived neurotrophic factor levels as a novel biological marker for the activities of psychiatric symptoms in systemic lupus erythematosus.
abstract: OBJECTIVE
  Neuropsychiatric systemic lupus erythematosus (NPSLE) is a serious but potentially treatable disease. However, biological markers such as IgG index or IL-6 do not always reflect the severity of the psychotic symptoms of NPSLE. We hypothesized that serum BDNF levels may be a biological marker for reflecting the severity of the psychiatric symptoms of NPSLE.
  
  
  METHODS
  The participants enrolled in this study were 28 healthy volunteers and 54 Japanese SLE inpatients at the University Hospital of Occupational and Environmental Health, all of whom fulfilled the criteria for the classification of SLE. SLE patients were divided into the three groups: NPSLE with psychiatric symptoms including an acute confusional state, anxiety disorder, cognitive dysfunction, mood disorder, and psychosis (NP group); NPSLE without psychiatric symptoms (NN group); and SLE without neuropsychiatric symptoms (S group). The serum BDNF levels were measured by ELISA.
  
  
  RESULTS
  Serum BDNF levels were significantly increased in the NP group (mean +/- SE = 37.0 +/- 5.46 ng/ml) compared with those in the other three groups (NN group; mean +/- SE = 9.1 +/- 2.44 ng/ml, P < 0.0001, S group; mean +/- SE = 10.4 +/- 2.51 ng/ml, P < 0.0001, healthy control; mean +/- SE = 11.44 +/- 0.69, P < 0.0001). Subsequently, serum BDNF levels were decreased in parallel with the improvement of psychiatric symptoms in the NP group.
  
  
  CONCLUSIONS
  These results suggest that serum BDNF is a biological marker for the severity of psychiatric symptoms in NPSLE patients.
authors.affiliation: Department of Psychiatry, University of Occupational and Environmental Health, School of Medicine, Yahatanishi-ku, Kitakyushu, Japan.
authors.forename: Atsuko
authors.initials: A
authors.lastname: Ikenouchi-Sugita
authors.forename: Reiji
authors.initials: R
authors.lastname: Yoshimura
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Okamoto
authors.forename: Wakako
authors.initials: W
authors.lastname: Umene-Nakano
authors.forename: Nobuhisa
authors.initials: N
authors.lastname: Ueda
authors.forename: Hikaru
authors.initials: H
authors.lastname: Hori
authors.forename: Asuka
authors.initials: A
authors.lastname: Katsuki
authors.forename: Kazuyoshi
authors.initials: K
authors.lastname: Saito
authors.forename: Yoshiya
authors.initials: Y
authors.lastname: Tanaka
authors.forename: Jun
authors.initials: J
authors.lastname: Nakamura
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000097:blood*; D019208:Brain-Derived Neurotrophic Factor / Q000097:blood*; D016022:Case-Control Studies; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D008180:Lupus Erythematosus, Systemic / Q000097:blood* / Q000150:complications / Q000523:psychology; D020945:Lupus Vasculitis, Central Nervous System / Q000097:blood / Q000150:complications / Q000523:psychology; D008297:Male; D001523:Mental Disorders / Q000097:blood / Q000175:diagnosis / Q000209:etiology*; D008875:Middle Aged; D055815:Young Adult
chemical_list: D015415:Biomarkers; D019208:Brain-Derived Neurotrophic Factor; D007074:Immunoglobulin G