Liver function in Huntington's disease assessed by blood biochemical analyses in a clinical setting

Abstract

Huntington's disease (HD) is a dominantly inherited, progressive neurological disorder caused by a CAG repeat elongation in the huntingtin gene. In addition to motor-, psychiatric- and cognitive dysfunction, peripheral disease manifestations in the form of metabolic changes and cellular dysfunction are seen. Blood levels of a wide range of hormones, metabolites and proteins have been analyzed in HD patients, identifying several changes associated with the disease. However, a comprehensive panel of liver function tests (LFT) has not been performed. We investigated a cohort of manifest and premanifest HD gene-expansion carriers and controls, using a clinically applied panel of LFTs. Here, we demonstrate that the level of alkaline phosphatase is increased in manifest HD gene-expansion carriers compared to premanifest HD gene-expansion carriers and correlate with increased disease severity indicated by the Unified Huntington's disease rating scale-Total Functional Capacity Score (UHDRS-TFC). For gamma-glutamyl transferase, elevated levels were more frequent in the manifest groups than in both the HD gene-expansion negative controls and premanifest HD gene-expansion carriers. Finally, the manifest HD gene-expansion carriers displayed moderate increases in total cholesterol and blood glucose relative to the premanifest HD gene-expansion carriers, as well as increased C-reactive protein relative to HD gene-expansion negative controls. Our results show that LFT values are elevated more frequently in manifest compared to premanifest HD gene-expansion carriers and controls. The majority of the manifest HD gene-expansion carriers receive medication, and it is possible that this can influence the liver function tests performed in this study.