Researchers have identified early biomarkers of Huntington's disease (HD) during examinations of HD sheep still at a pre-symptomatic stage of the disease. Up until this point, the five-year-old HD sheep displayed no signs of the illness, but this comprehensive study identified clear metabolic changes in the affected animals. These new findings reveal that Huntington's disease affects important metabolic processes in the body prior to the appearance of physical symptoms.
During this study, blood samples were taken from normal and HD animals every two hours over a 24-hour period and their metabolic profiles assessed using a targeted metabolomics approach. Unlike previous research in this area, which was affected by external environmental factors that impacted upon metabolic profiling, sheep in this study were monitored in a well-controlled setting, negating any outside influences.
Blood measurements found startling differences in the biochemistry of the sheep carrying the HD gene, compared to the normal sheep. Significant changes were observed in 89 of the 130 metabolites measured in their blood, with increased levels of the amino acids, arginine and citrulline, and decreases in sphingolipids and fatty acids that are commonly found in brain and nervous tissue. The alterations in these metabolites, which include key components of the urea cycle and nitric oxide pathways (both vital body processes), suggest that both of these processes are dysregulated in the early stages of Huntington's disease, and that the illness affects the body long before physical symptoms appear.
The identification of these biomarkers may help to track disease in pre-symptomatic patients, and could help researchers develop strategies to remedy the biochemical abnormalities.
Paper: “Metabolic profiling of presymptomatic Huntington’s disease sheep reveals novel biomarkers”
Reprinted from materials provided by University of Surrey.