Using 1H-NMR based metabolomics to investigate the pathological consequences of mitochondrial disease and human rabies infection

  • Author / Creator
    Reinke, Stacey N
  • Mitochondrial diseases encompass a wide range of clinical phenotypes. The etiology of these disorders is extremely complex; mitochondria are central to energy metabolism and dysfunction can have a profound effect on global metabolism. The original objective of this thesis was to use 1H-NMR based metabolomics to investigate the metabolic mechanisms of mitochondrial disease. Metabolomics is the systematic study of metabolites and is a powerful approach to understanding disease. In the clinical realm, metabolomics is useful for identifying biomarkers of disease and for understanding disease mechanisms. The metabolome is extremely sensitive to a number of factors, such as genetic background, age, diet, gender and stress; it is therefore difficult to meaningfully interpret results from human metabolomic data. For this reason, we chose to employ two common laboratory models of mitochondrial disease: the nematode Caenorhabditis elegans and the yeast Saccharomyces cerevisiae. These model systems provide the opportunity to study mitochondrial disease in a well-defined genetic background under controlled environmental conditions. Our findings revealed that even in a highly-controlled experiment, an appreciable amount of biological variability still exists. In the laboratory, C. elegans can be fed two different strains of E. coli: OP50 for regular maintenance and HT115 for RNAi-mediated gene suppression. We discovered that the nematode metabotype, mtDNA copy number, brood size and lifespan are significantly altered by diet. We also investigated the metabolic consequences of Complex II dysfunction in yeast, as reflected in the extracellular metabolome or exometabolome. Metabolomic studies are frequently used to identify a small number of key biomarkers that discriminate individuals of different phenotypes. Our exometabolome data revealed that the entire metabolome contributes to discrimination between phenotypic classes. Amino acid metabolism, which is closely linked to energy metabolism, was profoundly affected by mitochondrial dysfunction in both model systems. I also investigated the pathogenic, molecular and metabolic consequences of a human rabies infection following an aggressive and controversial neuro-therapeutic treatment protocol, revealing a possible adverse and fatal consequence of this procedure.

  • Subjects / Keywords
  • Graduation date
    Spring 2012
  • Type of Item
  • Degree
    Doctor of Philosophy
  • DOI
  • License
    This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.