title: A positive correlation between serum levels of mature brain-derived neurotrophic factor and negative symptoms in schizophrenia.
abstract: A meta-analysis study reported serum brain-derived neurotrophic factor (BDNF) levels as a potential biomarker for schizophrenia. However, at the time, commercially available human ELISA kits were unable to distinguish between pro-BDNF (precursor BDNF) and mature BDNF, because of limited antibody specificity. Here, we used new ELISA kits, to examine serum levels of mature BDNF and matrix metalloproteinase-9 (MMP-9), which converts pro-BDNF to mature BDNF in schizophrenia. Sixty-three patients with chronic schizophrenia and 52 age- and sex-matched healthy controls were enrolled. Patients were evaluated using the Brief Psychiatry Rating Scale, the Scale for the Assessment of Negative Symptoms (SANS) and neuropsychological tests. Neither serum mature BDNF nor MMP-9 levels differed between patients and controls. In male subgroups, serum MMP-9 levels of smoking patients were higher than those of non-smoking patients, but this was not observed in male controls or the female subgroup. In patients, serum mature BDNF levels were associated with SANS total scores and the Information subtest scores of the Wechsler Adult Intelligence Scale Revised (WAIS-R), while serum MMP-9 levels were associated with smoking and category fluency scores. These findings suggest that neither mature BDNF nor MMP-9 is a suitable biomarker for schizophrenia, although further studies using large samples are needed.
authors.affiliation: Research Center for Child Mental Development, Chiba University Graduate School of Medicine, Chiba, Japan. Electronic address: niitsu@chiba-u.jp.
authors.forename: Tomihisa
authors.initials: T
authors.lastname: Niitsu
authors.affiliation: Division of Clinical Neuroscience, Chiba University Center for Forensic Mental Health, Chiba, Japan.
authors.forename: Tamaki
authors.initials: T
authors.lastname: Ishima
authors.affiliation: Department of Psychiatry, Chiba University Graduate School of Medicine, Chiba, Japan.
authors.forename: Taisuke
authors.initials: T
authors.lastname: Yoshida
authors.affiliation: Department of Psychiatry, Chiba University Graduate School of Medicine, Chiba, Japan.
authors.forename: Tasuku
authors.initials: T
authors.lastname: Hashimoto
authors.affiliation: Research Center for Child Mental Development, Chiba University Graduate School of Medicine, Chiba, Japan; Department of Cognitive Behavioral Physiology, Chiba University Graduate School of Medicine, Chiba, Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Matsuzawa
authors.affiliation: Department of Psychiatry, Teikyo University Chiba Medical Center, Ichihara, Japan.
authors.forename: Yukihiko
authors.initials: Y
authors.lastname: Shirayama
authors.affiliation: Research Center for Child Mental Development, Chiba University Graduate School of Medicine, Chiba, Japan.
authors.forename: Michiko
authors.initials: M
authors.lastname: Nakazato
authors.affiliation: Research Center for Child Mental Development, Chiba University Graduate School of Medicine, Chiba, Japan; Department of Cognitive Behavioral Physiology, Chiba University Graduate School of Medicine, Chiba, Japan.
authors.forename: Eiji
authors.initials: E
authors.lastname: Shimizu
authors.affiliation: Division of Clinical Neuroscience, Chiba University Center for Forensic Mental Health, Chiba, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Hashimoto
authors.affiliation: Division of Clinical Neuroscience, Chiba University Center for Forensic Mental Health, Chiba, Japan; Department of Psychiatry, Chiba University Graduate School of Medicine, Chiba, Japan.
authors.forename: Masaomi
authors.initials: M
authors.lastname: Iyo
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000097:blood; D019208:Brain-Derived Neurotrophic Factor / Q000097:blood*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D008297:Male; D020780:Matrix Metalloproteinase 9 / Q000097:blood; D009483:Neuropsychological Tests; D012559:Schizophrenia / Q000097:blood*; D012565:Schizophrenic Psychology; D012737:Sex Factors
chemical_list: D015415:Biomarkers; D019208:Brain-Derived Neurotrophic Factor; D020780:Matrix Metalloproteinase 9
keywords: Biomarker; ELISA; Gender; MMP-9; Mature BDNF; SANS; Smoking