Decreased N-acetyl-aspartate/choline ratio and increased lactate in the frontal lobe of patients with Huntington's disease: a proton magnetic resonance spectroscopy study.

Abstract

BACKGROUND: Both the effect of the mutation and the pathogenesis of Huntington's disease are unknown and a lack of biological markers for the natural history of the disease impedes the evaluation of novel therapeutic approaches. METHODS: Proton magnetic resonance spectroscopy was carried out on a frontal region of the cortex in 17 patients with clinically overt Huntington's disease and four asymptomatic gene carriers. RESULTS: Eight of 17 (47%) clinically affected patients with Huntington's disease and each of the asymptomatic carriers had lactate peaks in the frontal cortex which were not present in controls. The N-acetyl-aspartate/choline (NAA/Ch) ratio was significantly reduced in the symptomatic patients indicating the presence of neuronal loss. The reduction was related to the clinical severity of the disease and was absent in the asymptomatic carriers. CONCLUSION: The finding of lactate peaks supports the hypothesis that disturbed cerebral energy metabolism contributes to the pathogenesis of Huntington's disease.