title: Abnormal response to cortical activation in early stages of Huntington disease.
abstract: BACKGROUND
  We wished to identify noninvasive in vivo biomarkers of brain energy deficit in Huntington disease.
  
  
  METHODS
  We studied 15 early affected patients (mean motor United Huntington Disease Rating Scale, 18 ± 9) and 15 age- and sex-matched controls. We coupled (31)phosphorus nuclear magnetic resonance spectroscopy with activation of the occipital cortex in order to measure the relative concentrations of adenosine triphosphate, phosphocreatine, and inorganic phosphate before, during, and after visual stimulation.
  
  
  RESULTS
  In controls, we observed an 11% increase in the inorganic phosphate/phosphocreatine ratio (P = .024) and a 13% increase in the inorganic phosphate/adenosine triphosphate ratio (P = .016) during brain activation, reflecting increased adenosine diphosphate concentrations. Subsequently, controls had a return to baseline levels during recovery (P = .012 and .022, respectively). In contrast, both ratios were unchanged in patients during and after visual stimulation.
  
  
  CONCLUSIONS
  (31)Phosphorus nuclear magnetic resonance spectroscopy could provide functional biomarkers of brain energy deficit to monitor therapeutic efficacy in Huntington disease.
authors.affiliation: INSERM UMR S975, Institut du Cerveau et de la Moelle, Hôpital La Salpêtrière, Paris, France. fanny.mochel@upmc.fr
authors.forename: Fanny
authors.initials: F
authors.lastname: Mochel
authors.forename: Tra-My
authors.initials: TM
authors.lastname: N'Guyen
authors.forename: Dinesh
authors.initials: D
authors.lastname: Deelchand
authors.forename: Daisy
authors.initials: D
authors.lastname: Rinaldi
authors.forename: Romain
authors.initials: R
authors.lastname: Valabregue
authors.forename: Claire
authors.initials: C
authors.lastname: Wary
authors.forename: Pierre G
authors.initials: PG
authors.lastname: Carlier
authors.forename: Alexandra
authors.initials: A
authors.lastname: Durr
authors.forename: Pierre-Gilles
authors.initials: PG
authors.lastname: Henry
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D016022:Case-Control Studies; D002540:Cerebral Cortex / Q000000981:diagnostic imaging / Q000378:metabolism* / Q000503:physiopathology; D005260:Female; D006801:Humans; D006816:Huntington Disease / Q000000981:diagnostic imaging / Q000473:pathology*; D016014:Linear Models; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D010710:Phosphates / Q000378:metabolism; D010725:Phosphocreatine / Q000378:metabolism; D010759:Phosphorus Isotopes / Q000378:metabolism; D011877:Radionuclide Imaging
chemical_list: D010710:Phosphates; D010759:Phosphorus Isotopes; D010725:Phosphocreatine; D000255:Adenosine Triphosphate