title: Abnormalities in metabolite concentrations in tourette's disorder and obsessive-compulsive disorder-A proton magnetic resonance spectroscopy study.
abstract: Abnormal glutamatergic transmission in cortico-striato-thalamo-cortical (CSTC) circuits is thought to be involved in the pathophysiology of Tourette's disorder (TD) and obsessive-compulsive disorder (OCD). Using proton magnetic resonance spectroscopy, the current study aimed to investigate regional concentrations of glutamatergic compounds in TD and OCD patients in comparison to healthy control subjects (HC).
  
  
  
  Twenty-three TD patients, 20 OCD patients and 22 HC were included. Short echo-time single-voxel 3T MRS was obtained from dorsal anterior cingulate cortex (dACC) and midline bilateral thalamus.
  
  
  
  The 3-group comparison showed a significant difference in choline concentration in the thalamus. Thalamic choline was highest in OCD patients, showing a significant difference with TD, and a trend compared to HC (post-hoc analyses). Glutamine in dACC correlated negatively with tic severity scores in TD patients, while glutamate in thalamus correlated positively with anxiety severity scores in OCD patients.
  
  
  
  These findings suggest subtle differences in metabolites in CSTC areas between TD and OCD. Alterations of choline concentrations seem to be both regional (only in thalamus, not in dACC) and disease specific in OCD pathology. The findings need replication in larger groups, but encourage further research into glutamatergic metabolites in TD and OCD.
authors.affiliation: Division of Social and Behavioural Science, Utrecht University, Utrecht, The Netherlands; Department of Anatomy and Neurosciences, VU university medical center (VUmc), Amsterdam, The Netherlands; Department of Psychiatry, VUmc, Amsterdam, The Netherlands. Electronic address: s.fan@vumc.nl.
authors.forename: Siyan
authors.initials: S
authors.lastname: Fan
authors.affiliation: Division of Social and Behavioural Science, Utrecht University, Utrecht, The Netherlands; Altrecht Academic Anxiety Center, Utrecht, The Netherlands.
authors.forename: Danielle C
authors.initials: DC
authors.lastname: Cath
authors.affiliation: Department of Anatomy and Neurosciences, VU university medical center (VUmc), Amsterdam, The Netherlands; Department of Psychiatry, VUmc, Amsterdam, The Netherlands; Neuroscience Campus Amsterdam, VU/VUmc, Amsterdam, The Netherlands; The OCD team, Haukeland University Hospital, Bergen, Norway.
authors.forename: Odile A
authors.initials: OA
authors.lastname: van den Heuvel
authors.affiliation: Department of Anatomy and Neurosciences, VU university medical center (VUmc), Amsterdam, The Netherlands; Neuroscience Campus Amsterdam, VU/VUmc, Amsterdam, The Netherlands.
authors.forename: Ysbrand D
authors.initials: YD
authors.lastname: van der Werf
authors.affiliation: Division of Social and Behavioural Science, Utrecht University, Utrecht, The Netherlands; Altrecht Academic Anxiety Center, Utrecht, The Netherlands.
authors.forename: Caroline
authors.initials: C
authors.lastname: Schöls
authors.affiliation: Department of Psychiatry, VUmc, Amsterdam, The Netherlands; Neuroscience Campus Amsterdam, VU/VUmc, Amsterdam, The Netherlands.
authors.forename: Dick J
authors.initials: DJ
authors.lastname: Veltman
authors.affiliation: Neuroscience Campus Amsterdam, VU/VUmc, Amsterdam, The Netherlands; Department of Physics & Medical Technology, VUmc, Amsterdam, The Netherlands.
authors.forename: Petra J W
authors.initials: PJW
authors.lastname: Pouwels
mesh_terms: D000328:Adult; D002794:Choline / Q000378:metabolism*; D005260:Female; D018698:Glutamic Acid / Q000378:metabolism*; D005973:Glutamine / Q000378:metabolism*; D006179:Gyrus Cinguli / Q000000981:diagnostic imaging / Q000378:metabolism*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009771:Obsessive-Compulsive Disorder / Q000000981:diagnostic imaging / Q000378:metabolism*; D066244:Proton Magnetic Resonance Spectroscopy; D013788:Thalamus / Q000000981:diagnostic imaging / Q000378:metabolism*; D005879:Tourette Syndrome / Q000000981:diagnostic imaging / Q000378:metabolism*; D055815:Young Adult
chemical_list: D005973:Glutamine; D018698:Glutamic Acid; D002794:Choline
keywords: Choline; Dorsal cingulate cortex; Magnetic resonance spectroscopy; Obsessive-compulsive disorder; Thalamus; Tourette’s disorder