title: Simultaneous monitoring of cerebral metal accumulation in an experimental model of Wilson's disease by laser ablation inductively coupled plasma mass spectrometry.
abstract: BACKGROUND
  Neuropsychiatric affection involving extrapyramidal symptoms is a frequent component of Wilson's disease (WD). WD is caused by a genetic defect of the copper (Cu) efflux pump ATPase7B. Mouse strains with natural or engineered transgenic defects of the Atp7b gene have served as model of WD. These show a gradual accumulation and concentration of Cu in liver, kidneys, and brain. However, still little is known about the regional distribution of Cu inside the brain, its influence on other metals and subsequent pathophysiological mechanisms. We have applied laser ablation inductively coupled plasma mass spectrometry and performed comparative metal bio-imaging in brain sections of wild type and Atp7b null mice in the age range of 11-24 months. Messenger RNA and protein expression of a panel of inflammatory markers were assessed using RT-PCR and Western blots of brain homogenates.
  
  
  RESULTS
  We could confirm Cu accumulation in brain parenchyma by a factor of two in WD (5.5 μg g(-1) in the cortex) vs. controls (2.7 μg g(-1)) that was already fully established at 11 months. In the periventricular regions (PVR) known as structures of prominent Cu content, Cu was reduced in turn by a factor of 3. This corroborates the view of the PVR as efflux compartments with active transport of Cu into the cerebrospinal fluid. Furthermore, the gradient of Cu increasing downstream the PVR was relieved. Otherwise the architecture of Cu distribution was essentially maintained. Zinc (Zn) was increased by up to 40% especially in regions of high Cu but not in typical Zn accumulator regions, a side effect due to the fact that Zn is to some degree a substrate of Cu-ATPases. The concentrations of iron (Fe) and manganese (Mn) were constant throughout all regions assessed. Inflammatory markers TNF-α, TIMP-1 and the capillary proliferation marker α-SMA were increased by a factor of 2-3 in WD.
  
  
  CONCLUSIONS
  This study confirmed stable cerebral Cu accumulation in parenchyma and discovered reduced Cu in cerebrospinal fluid in Atp7b null mice underlining the diagnostic value of micro-local analytical techniques.
authors.forename: Sorina Georgiana
authors.initials: SG
authors.lastname: Boaru
authors.forename: Uta
authors.initials: U
authors.lastname: Merle
authors.forename: Ricarda
authors.initials: R
authors.lastname: Uerlings
authors.forename: Astrid
authors.initials: A
authors.lastname: Zimmermann
authors.forename: Sabine
authors.initials: S
authors.lastname: Weiskirchen
authors.forename: Andreas
authors.initials: A
authors.lastname: Matusch
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Stremmel
authors.affiliation: Institute of Clinical Chemistry and Pathobiochemistry, RWTH Aachen University Hospital Aachen, Pauwelsstr, 30, D-52074 Aachen, Germany. rweiskirchen@ukaachen.de.
authors.forename: Ralf
authors.initials: R
authors.lastname: Weiskirchen
mesh_terms: D000199:Actins / Q000378:metabolism; D000251:Adenosine Triphosphatases / Q000235:genetics / Q000378:metabolism; D000375:Aging / Q000378:metabolism; D000818:Animals; D015153:Blotting, Western; D001921:Brain / Q000378:metabolism*; D027682:Cation Transport Proteins / Q000235:genetics / Q000378:metabolism; D003300:Copper / Q000134:cerebrospinal fluid / Q000378:metabolism*; D000073840:Copper-Transporting ATPases; D004195:Disease Models, Animal; D018450:Disease Progression; D006527:Hepatolenticular Degeneration / Q000134:cerebrospinal fluid / Q000378:metabolism*; D007501:Iron / Q000378:metabolism*; D053685:Laser Therapy / Q000379:methods; D008345:Manganese / Q000378:metabolism*; D013058:Mass Spectrometry / Q000379:methods; D057507:Mice, 129 Strain; D018345:Mice, Knockout; D012333:RNA, Messenger / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D019715:Tissue Inhibitor of Metalloproteinase-1 / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism; D015032:Zinc / Q000378:metabolism*
chemical_list: D000199:Actins; C486201:Atp7a protein, mouse; D027682:Cation Transport Proteins; D012333:RNA, Messenger; C560825:Timp1 protein, mouse; D019715:Tissue Inhibitor of Metalloproteinase-1; D014409:Tumor Necrosis Factor-alpha; C544013:alpha-smooth muscle actin, mouse; D008345:Manganese; D003300:Copper; D007501:Iron; D000251:Adenosine Triphosphatases; D000073840:Copper-Transporting ATPases; D015032:Zinc