Effects of tryptophan depletion on serum levels of brain-derived neurotrophic factor in unmedicated patients with remitted depression and healthy subjects.
OBJECTIVE
Data suggest the involvement of serotonergic and neurotrophic systems in major depressive disorder. To investigate their potential interaction, the authors studied changes in serum levels of brain-derived neurotrophic factor (BDNF) during tryptophan depletion and sham depletion in unmedicated patients with remitted major depressive disorder and in a group of healthy comparison subjects.


METHODS
Twenty-seven patients with remitted major depressive disorder and 20 healthy subjects underwent tryptophan depletion and sham depletion in a randomized, placebo-controlled, double-blind crossover study. Serum BDNF concentrations and plasma tryptophan concentrations as well as behavioral assessments were obtained.


RESULTS
During tryptophan depletion, BDNF levels increased in healthy volunteers. By contrast, patients with remitted major depressive disorder were unable to mount this presumed compensatory response, and BDNF levels remained low in these patients.


CONCLUSIONS
The results further substantiate the potential role of BDNF in major depressive disorder.
Neumeister
Alexander
A
NIMH Mood and Anxiety Disorders Program, Bethesda, MD, USA. alexander.neumeister@yale.edu
Yuan
Peixiong
P
Young
Theresa A
TA
Bonne
Omer
O
Luckenbaugh
David A
DA
Charney
Dennis S
DS
Manji
Husseini
H
D015415:Biomarkers / Q000097:blood / Q000134:cerebrospinal fluid / Q000378:metabolism; D019208:Brain-Derived Neurotrophic Factor / Q000097:blood* / Q000378:metabolism; D018592:Cross-Over Studies; D003865:Major Depressive Disorder / Q000097:blood* / Q000175:diagnosis / Q000523:psychology*; D004311:Double-Blind Method; D006801:Humans; D011569:Psychiatric Status Rating Scales; D012701:Serotonin / Q000096:biosynthesis / Q000378:metabolism; D014364:Tryptophan / Q000097:blood* / Q000172:deficiency* / Q000378:metabolism
D015415:Biomarkers; D019208:Brain-Derived Neurotrophic Factor; D012701:Serotonin; D014364:Tryptophan