title: Differential neurometabolite alterations in brains of medication-free individuals with bipolar disorder and those with unipolar depression: a two-dimensional proton magnetic resonance spectroscopy study.
abstract: Bipolar disorder (BD) is a mental disorder characterized by periods of elevated mood and depression. Many individuals with BD are initially misdiagnosed and treated for unipolar depression (UD). In this study, we report direct comparisons between medication-free individuals with BD and those with UD in terms of the neurometabolites in the anterior cingulate cortex (ACC), medial prefrontal cortex (mPFC), parietal cortex (PC), and posterior cingulate cortex (PCC) of the brain.
  
  
  
  Participants included medication-free patients with BD or UD, and matched healthy controls. All patients were in the depressive state and had similar symptoms. All subjects were subjected to a multi-voxel proton magnetic resonance spectroscopy procedure with a 3.0 T GE Signa MR scanner. After post-processing, the absolute concentrations of glycerophosphocholine + phosphocholine (GPC + PC), phosphocreatine + creatine (PCr + Cr), Glx (glutamate + glutamine), myo-inositol (MI), and N-acetyl aspartate (NAA) from the above brain regions were compared across the three groups.
  
  
  
  Patients with BD showed significantly higher levels of Glx in their ACC, lower GPC + PC, PCr + Cr, MI, and NAA in their PC, and lower NAA in their mPFC, compared to healthy controls; patients with UD presented significantly lower levels of GPC + PC, PCr + Cr, and NAA in their PCC, and lower Glx in their mPFC. All analyzed brain metabolites, except Glx, were significantly lower in the PC of patients with BD, whereas levels of GPC + PC, PCr + Cr, and NAA were significantly reduced in the PCC of patients with UD.
  
  
  
  These results add to the evidence of brain metabolite differences in brains of patients with UD and BD which may be of help in differentiating these two mood disorders.
authors.affiliation: Mental Health Center, Shantou University Medical College, Shantou, China.|Department of Medical Imaging, The 2nd Affiliated Hospital, Shantou University Medical College, Shantou, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Li
authors.affiliation: Mental Health Center, Shantou University Medical College, Shantou, China.
authors.forename: Haiyun
authors.initials: H
authors.lastname: Xu
authors.affiliation: Mental Health Center, Shantou University Medical College, Shantou, China.
authors.forename: Yinnan
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Department of Medical Imaging, The 2nd Affiliated Hospital, Shantou University Medical College, Shantou, China.
authors.forename: Jitian
authors.initials: J
authors.lastname: Guan
authors.affiliation: Mental Health Center, Shantou University Medical College, Shantou, China.
authors.forename: Jie
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Mental Health Center, Shantou University Medical College, Shantou, China.
authors.forename: Chongtao
authors.initials: C
authors.lastname: Xu
authors.affiliation: Department of Medical Imaging, The 2nd Affiliated Hospital, Shantou University Medical College, Shantou, China.
authors.forename: Zhiwei
authors.initials: Z
authors.lastname: Shen
authors.affiliation: Mental Health Center, Shantou University Medical College, Shantou, China.
authors.forename: Bo
authors.initials: B
authors.lastname: Xiao
authors.affiliation: Mental Health Center, Shantou University Medical College, Shantou, China.
authors.forename: Chunlian
authors.initials: C
authors.lastname: Liang
authors.affiliation: Mental Health Center, Shantou University Medical College, Shantou, China.
authors.forename: Kaiyuan
authors.initials: K
authors.lastname: Chen
authors.affiliation: Mental Health Center, Shantou University Medical College, Shantou, China.
authors.forename: Jinling
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Department of Medical Imaging, The 2nd Affiliated Hospital, Shantou University Medical College, Shantou, China.|The Provincial Key Laboratory of Medical Molecular Imaging, Shantou, China.
authors.forename: Renhua
authors.initials: R
authors.lastname: Wu
mesh_terms: D000328:Adult; D001224:Aspartic Acid / Q000031:analogs & derivatives / Q000378:metabolism; D001714:Bipolar Disorder / Q000175:diagnosis / Q000378:metabolism; D002794:Choline / Q000378:metabolism; D003401:Creatine / Q000378:metabolism; D003866:Depressive Disorder / Q000175:diagnosis / Q000378:metabolism; D005260:Female; D006179:Gyrus Cinguli / Q000000981:diagnostic imaging / Q000378:metabolism; D006801:Humans; D007294:Inositol / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D010296:Parietal Lobe / Q000000981:diagnostic imaging; D017397:Prefrontal Cortex / Q000000981:diagnostic imaging / Q000378:metabolism; D066244:Proton Magnetic Resonance Spectroscopy / Q000379:methods*; D013223:Statistics as Topic
chemical_list: D001224:Aspartic Acid; D007294:Inositol; C000179:N-acetylaspartate; D003401:Creatine; D002794:Choline
keywords: bipolar disorder; magnetic resonance spectroscopy; unipolar depression