Spectroscopic correlates of antidepressant response to sleep deprivation and light therapy: a 3.0 Tesla study of bipolar depression.
Glutamate is the primary excitatory neurotransmitter of the human brain, and recent findings suggest a role for the glutamatergic system in the pathophysiology and treatment of mood disorders. Single proton magnetic resonance spectroscopy (1H-MRS) was used to study the relative in vivo levels of brain neural metabolites. We evaluated the effect of antidepressant treatments on the relative concentration of unresolved glutamate and glutamine (Glx) with GABA contamination (2.35 ppm peak) using single voxel 1H-MRS at 3.0 Tesla. We studied 19 inpatients (7 males, 12 females) affected by bipolar disorder type I, current depressive episode without psychotic features, before and after 1 week of treatment with repeated total sleep deprivation (TSD) combined with light therapy (LT). Chronobiological treatment caused a significant amelioration in mood levels. Changes in the brain Glx/creatine ratio followed a general trend toward decrease, with individual variability. We observed that the decrease in the Glx/creatine ratio significantly correlated with the improvement of both objective and subjective measures of depression.
Benedetti
Francesco
F
Department of Neuropsychiatric Sciences, Scientific Institute and University Vita-Salute San Raffaele, Milan, Italy. benedetti.francesco@hsr.it
Calabrese
Giovanna
G
Bernasconi
Alessandro
A
Cadioli
Marcello
M
Colombo
Cristina
C
Dallaspezia
Sara
S
Falini
Andrea
A
Radaelli
Daniele
D
Scotti
Giuseppe
G
Smeraldi
Enrico
E
D000328:Adult; D000928:Antidepressive Agents / Q000627:therapeutic use*; D001714:Bipolar Disorder / Q000378:metabolism / Q000473:pathology / Q000628:therapy; D001921:Brain / Q000187:drug effects / Q000378:metabolism / Q000473:pathology*; D003401:Creatine / Q000378:metabolism; D005260:Female; D018698:Glutamic Acid / Q000378:metabolism; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D008297:Male; D008875:Middle Aged; D010789:Phototherapy / Q000379:methods*; D011522:Protons; D012892:Sleep Deprivation / Q000139:chemically induced*
D000928:Antidepressive Agents; D011522:Protons; D018698:Glutamic Acid; D003401:Creatine