title: Increased choline-containing compounds in the orbitofrontal cortex and hippocampus in euthymic patients with bipolar disorder: a proton magnetic resonance spectroscopy study.
abstract: The neuronal mechanisms underlying the pathophysiology of bipolar disorder (BD) have not been fully characterized. The aim of this study was to compare metabolite levels in the hippocampus and the orbitofrontal cortex in a homogenous population of 12 euthymic patients with well-established BD and 12 age- and sex-matched healthy comparison subjects. Using a GE Signa, 3-Tesla scanner, we performed proton magnetic resonance spectroscopy (H-MRS) to examine levels of N-acetyl aspartate, glutamate and choline-containing compounds. Choline-containing compounds were significantly increased in the hippocampus and the orbitofrontal cortex in BD patients relative to control subjects. Significant elevations of glycerophosphocholine+phosphocholine (GPC+PCh) were measured in the hippocampus and the orbitofrontal cortex of patients. As choline is a marker of membrane phospholipid metabolism, the elevated choline in patients may indicate increased membrane breakdown in the brain regions examined. Abnormal neuronal loss within the hippocampus and orbitofrontal cortex further supports previous work suggesting that these regions are involved in the pathophysiology of BD.
authors.affiliation: Department of Psychiatry and Behavioural Neurosciences, Faculty of Health Sciences, McMaster University, F130-301 James Street South, Hamilton, Ontario, Canada L8P 3B6. rhandis@gmail.com <rhandis@gmail.com>
authors.forename: Rhandi
authors.initials: R
authors.lastname: Senaratne
authors.forename: Andrea M
authors.initials: AM
authors.lastname: Milne
authors.forename: Glenda M
authors.initials: GM
authors.lastname: MacQueen
authors.forename: Geoffrey B C
authors.initials: GB
authors.lastname: Hall
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D001224:Aspartic Acid / Q000031:analogs & derivatives / Q000378:metabolism; D001714:Bipolar Disorder / Q000175:diagnosis / Q000378:metabolism* / Q000503:physiopathology; D016022:Case-Control Studies; D002794:Choline / Q000378:metabolism*; D005260:Female; D005625:Frontal Lobe / Q000378:metabolism* / Q000503:physiopathology; D007839:Functional Laterality; D018698:Glutamic Acid / Q000378:metabolism; D005973:Glutamine / Q000378:metabolism; D005997:Glycerylphosphorylcholine / Q000378:metabolism; D006624:Hippocampus / Q000378:metabolism* / Q000503:physiopathology; D006801:Humans; D007091:Image Processing, Computer-Assisted; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D008297:Male; D008875:Middle Aged; D010767:Phosphorylcholine / Q000378:metabolism; D011569:Psychiatric Status Rating Scales; D012720:Severity of Illness Index
chemical_list: D005973:Glutamine; D010767:Phosphorylcholine; D001224:Aspartic Acid; D018698:Glutamic Acid; D005997:Glycerylphosphorylcholine; C000179:N-acetylaspartate; D002794:Choline