title: Altered serotonin transporter availability in patients with multiple sclerosis.
abstract: OBJECTIVE
  Modulation of the immune system by the CNS may involve serotonergic regulation via the brain serotonin transporters (SERT). This regulation may be disturbed in patients with CNS disorders including multiple sclerosis (MS). Central serotonergic mechanisms have not been investigated in MS by in vivo imaging. The objective of the study was to assess the availability of SERT in antidepressant-naive patients with MS by means of PET.
  
  
  METHODS
  Included in this study were 23 patients with MS and 22 matched healthy volunteers who were investigated with PET and the SERT-selective marker [(11)C]DASB, and distribution volume ratios were determined. Clinical assessment of the patients included the expanded disability status scale, the MS fatigue scale Würzburger Erschöpfungsinventar bei MS (WEIMuS) and the Beck Depression Inventory (BDI). The PET data were analysed with both volume-of-interest and voxel-based analyses to determine regional SERT availability.
  
  
  RESULTS
  Patients had lower SERT availability in the cingulate cortex, the thalamus and the insula, and increased availability in the orbitofrontal cortex. Patients with relapsing/remitting MS tended to have lower SERT in the hippocampus, whereas patients with primary progressive disease showed increased SERT availability in prefrontal regions. There was a positive correlation between SERT availability in the insula and both depression and fatigue scores (r = 0.56 vs. BDI, p = 0.02; r = 0.49 vs. WEIMuS, p = 0.05).
  
  
  CONCLUSIONS
  Serotonergic neurotransmission in MS patients is altered in limbic and paralimbic regions as well as in the frontal cortex that this appears to contribute to psychiatric symptoms of MS.
authors.affiliation: Department of Nuclear Medicine, University of Leipzig, Liebigstraße 18, 04103, Leipzig, Germany, swen.hesse@medizin.uni-leipzig.de.
authors.forename: Swen
authors.initials: S
authors.lastname: Hesse
authors.forename: Franziska
authors.initials: F
authors.lastname: Moeller
authors.forename: David
authors.initials: D
authors.lastname: Petroff
authors.forename: Donald
authors.initials: D
authors.lastname: Lobsien
authors.forename: Julia
authors.initials: J
authors.lastname: Luthardt
authors.forename: Ralf
authors.initials: R
authors.lastname: Regenthal
authors.forename: Georg-Alexander
authors.initials: GA
authors.lastname: Becker
authors.forename: Marianne
authors.initials: M
authors.lastname: Patt
authors.forename: Eva
authors.initials: E
authors.lastname: Thomae
authors.forename: Anita
authors.initials: A
authors.lastname: Seese
authors.forename: Philipp M
authors.initials: PM
authors.lastname: Meyer
authors.forename: Florian Then
authors.initials: FT
authors.lastname: Bergh
authors.forename: Osama
authors.initials: O
authors.lastname: Sabri
mesh_terms: D000328:Adult; D000814:Aniline Compounds; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000000981:diagnostic imaging*; D049268:Positron-Emission Tomography; D019275:Radiopharmaceuticals; D050486:Serotonin Plasma Membrane Transport Proteins / Q000378:metabolism*; D013440:Sulfides
chemical_list: C412822:3-amino-4-(2-dimethylaminomethylphenylsulfanyl)benzonitrile; D000814:Aniline Compounds; D019275:Radiopharmaceuticals; C493230:SLC6A4 protein, human; D050486:Serotonin Plasma Membrane Transport Proteins; D013440:Sulfides