Brain cholesterol, which is synthesized locally, is a major component of myelin and cell membranes and participates in neuronal functions, such as membrane trafficking, signal transduction, neurotransmitter release, and synaptogenesis. Here we show that brain cholesterol biosynthesis is reduced in multiple transgenic and knock-in Huntington's disease (HD) rodent models, arguably dependent on deficits in mutant astrocytes. Mice carrying a progressively increased number of CAG repeats show a more evident reduction in cholesterol biosynthesis.
View Article and Find Full Text PDFHuntington's disease (HD) is one of the most common autosomal dominant inherited, neurodegenerative disorders. It is characterized by progressive motor, emotional and cognitive dysfunction. In addition metabolic abnormalities such as wasting and altered energy expenditure are increasingly recognized as clinical hallmarks of the disease.
View Article and Find Full Text PDFOnset of genetically determined neurodegenerative diseases is difficult to specify because of their insidious and slowly progressive nature. This is especially true for spinocerebellar ataxia (SCA) because of varying affection of many parts of the nervous system and huge variability of symptoms. We investigated early symptoms in 287 patients with SCA1, SCA2, SCA3, or SCA6 and calculated the influence of CAG repeat length on age of onset depending on (1) the definition of disease onset, (2) people defining onset, and (3) duration of symptoms.
View Article and Find Full Text PDFFriedreich ataxia (FRDA) is associated with a GAA-trinucleotide-repeat expansion in the first intron of the FXN gene (9q13-21), which encodes a 210-amino-acid protein named frataxin. More than 95% of patients are homozygous for 90-1,300 repeat expansion on both alleles. The remaining patients have been shown to be compound heterozygous for a GAA expansion on one allele and a micromutation on the other.
View Article and Find Full Text PDFAn expanded polyglutamine stretch in the huntingtin protein has been identified as the pathogenetic cause of Huntington's disease (HD). Although the length of the expanded polyglutamine repeat is inversely correlated with the age-at-onset, additional genetic factors are thought to modify the variance in the disease onset. As linkage analysis suggested a modifier locus on chromosome 4p, we investigated the functional relevance of S18Y polymorphism of the ubiquitin carboxy-terminal hydrolase L1 in 946 Caucasian HD patients.
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