Introduction Metabolic changes have been frequently associated with Huntington's disease (HD). At the same time peripheral blood represents aminimally invasive sampling avenue with little distress... Show moreIntroduction Metabolic changes have been frequently associated with Huntington's disease (HD). At the same time peripheral blood represents aminimally invasive sampling avenue with little distress to Huntington's disease patients especially when brain or other tissue samples are difficult to collect.Objectives We investigated the levels of 163 metabolites in HD patient and control serum samples in order to identify disease related changes. Additionally, we integrated the metabolomics data with our previously published next generation sequencing-based gene expression data from the same patients in order to interconnect the metabolomics changes with transcriptional alterations. Methods This analysis was performed using targeted metabolomics and flow injection electrospray ionization tandem mass spectrometry in 133 serum samples from 97 Huntington's disease patients (29 pre-symptomatic and 68 symptomatic) and 36 controls.Results By comparing HD mutation carriers with controls we identified 3 metabolites significantly changed in HD (serine and threonine and one phosphatidylcholine-PC ae C36:0) and an additional 8 phosphatidylcholines (PC aa C38:6, PC aa C36:0, PC ae C38:0, PC aa C38:0, PC ae C38:6, PC ae C42:0, PC aa C36:5 and PC ae C36:0) that exhibited a significant association with disease severity. Using workflow based exploitation of pathway databases and by integrating our metabolomics data with our gene expression data from the same patients we identified 4 deregulated phosphatidylcholine metabolism related genes (ALDH1B1, MBOAT1, MTRR and PLB1) that showed significant association with the changes in metabolite concentrations.Conclusion Our results support the notion that phosphatidylcholine metabolism is deregulated in HD blood and that these metabolite alterations are associated with specific gene expression changes. Show less
This thesis describes attempts to identify novel pathophysiology based biomarkers for chronic airway disease by applying newer detection techniques. It appears that such an approach may be... Show moreThis thesis describes attempts to identify novel pathophysiology based biomarkers for chronic airway disease by applying newer detection techniques. It appears that such an approach may be worthwhile to pursue. Further, it shows that application of biomarkers allows effective development of new therapies in chronic airway disease. Show less
In this thesis the epidemiology of suicidal ideation and suicide attempts (together referred to as 'suicidality') in Huntington's disease (HD) is investigated and coping styles and support... Show moreIn this thesis the epidemiology of suicidal ideation and suicide attempts (together referred to as 'suicidality') in Huntington's disease (HD) is investigated and coping styles and support strategies that may serve to help suicidal HD mutation carriers are explored. Suicidality frequently occurs in HD, with a 1-month prevalence of up to 20%. Mutation carriers who were most likely to currently experience suicidal ideation or suicidality had a shorter disease duration, were anxious, aggressive, previously attempted suicide, used antidepressants, and had a depressed mood. The presence of a depressed mood and use of benzodiazepines were the only significant independent predictors of incident suicidal ideation or suicidality. Biological parameters, in particular functioning of the immune system and the hypothalamus-pituitary-adrenal axis were not found to be associated with suicidality in HD. In a qualitative study it was shown that suicidal HD mutation carriers generally used four strategies to cope with suicidality: talking about suicidality, employing self-management activities, using medication, and discussing end-of-life wishes. Lastly, in a meta-analysis, we examined whether the expression of suicidal ideation predicted subsequent completed suicide. Effect estimates differed substantially among different populations, but none of the included studies investigated this association in HD. Show less
