Decreased levels of serum brain-derived neurotrophic factor in drug-naïve first-episode schizophrenia: relationship to clinical phenotypes.
OBJECTIVE
There is accumulating evidence that brain-derived neurotrophic factor (BDNF) may be involved in the pathophysiology of patients with schizophrenia. Clinical studies show reductions in BDNF in schizophrenic patients treated with first generation antipsychotics or second generation antipsychotics. However, there have been few systematic studies to examine the relationship between BDNF levels and psychopathology in first-episode and drug-naïve patients with schizophrenia.


METHODS
Serum BDNF levels were determined using enzyme-linked-immunosorbent assay (ELISA) in the serum of 88 never-medicated first-episode and 90 healthy controls subjects matched for age and gender. The schizophrenia symptomatology and the depressive symptoms were assessed by the positive and negative syndrome scale (PANSS) and the Hamilton rating (HAMD) scale for depression.


RESULTS
The results showed that BDNF levels were significantly lower in first-episode patients with schizophrenia than in healthy control subjects (9.0 +/- 4.2 ng/ml vs 12.1 +/- 2.2 ng/ml; F = 37.6; df = 1, 176; p < 0.0001). A significant positive correlation between BDNF levels and PANSS positive subscore was observed (r = 0.29; df = 88; p = 0.008). Furthermore, higher BDNF levels were observed in patients with paranoid subtype of schizophrenia. However, no significant correlation between BDNF and HAMD total score was found.


CONCLUSIONS
Low BDNF levels at the onset of psychosis suggest that it may contribute to the pathogenesis of schizophrenia and perhaps, could be a candidate biological marker for positive symptoms.
Beijing Huilongguan Hospital, Beijing, People's Republic of China.
Da Chun
DC
Chen
Jing
J
Wang
Bo
B
Wang
Sheng Chang
SC
Yang
Chong Xi
CX
Zhang
You Lan
YL
Zheng
Yan Li
YL
Li
Ning
N
Wang
Ke Bing
KB
Yang
Mei Hong
MH
Xiu
Thomas R
TR
Kosten
Xiang Yang
XY
Zhang
D000293:Adolescent; D000328:Adult; D015415:Biomarkers / Q000097:blood; D019208:Brain-Derived Neurotrophic Factor / Q000097:blood*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011569:Psychiatric Status Rating Scales; D012559:Schizophrenia / Q000097:blood* / Q000503:physiopathology; D012565:Schizophrenic Psychology
D015415:Biomarkers; D019208:Brain-Derived Neurotrophic Factor