title: Effects of tryptophan depletion on serum levels of brain-derived neurotrophic factor in unmedicated patients with remitted depression and healthy subjects.
abstract: 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.
authors.affiliation: NIMH Mood and Anxiety Disorders Program, Bethesda, MD, USA. alexander.neumeister@yale.edu
authors.forename: Alexander
authors.initials: A
authors.lastname: Neumeister
authors.forename: Peixiong
authors.initials: P
authors.lastname: Yuan
authors.forename: Theresa A
authors.initials: TA
authors.lastname: Young
authors.forename: Omer
authors.initials: O
authors.lastname: Bonne
authors.forename: David A
authors.initials: DA
authors.lastname: Luckenbaugh
authors.forename: Dennis S
authors.initials: DS
authors.lastname: Charney
authors.forename: Husseini
authors.initials: H
authors.lastname: Manji
mesh_terms: 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
chemical_list: D015415:Biomarkers; D019208:Brain-Derived Neurotrophic Factor; D012701:Serotonin; D014364:Tryptophan