Development of Techniques and Applications for CIL LC-MS Based Sweat Metabolomics

• Author / Creator

  Hooton, Kevin M

• The most often used biofluids in metabolomics and disease biomarker discovery studies in the literature include urine, processed blood (serum or plasma), and cerebral spinal fluid. While investigations using these biofluids have led to numerous innovations in the field of metabolomics, little attention has been given to the possible clinical relevance of sweat. Very few studies have attempted to perform global sweat metabolomics with high sensitivity, coverage, and accurate quantification. The goal of this thesis work was to develop robust, sensitive, and accurate analytical workflows to use sweat in CIL LC-MS global metabolomics. In Chapter 2, we profiled the metabolome of pure liquid sweat collected using an occlusive style sweat patch during 3 time points of moderate to intense exercise. Over 2707 unique metabolites were detected across 54 sweat samples collected from six individuals. We were able to positively identify 83 metabolites using a dansyl standard library, many of them never being reported as a part of the sweat metabolome. We observed significant metabolome differences in early vs. late exercise sweat samples, as well as between genders. This study demonstrated that CIL LC-MS can be used to detect metabolic changes in the sweat metabolome between comparative samples, justifying the use of sweat for future quantitative metabolomics research. Chapter 3 describes an improved sweat metabolomics workflow that uses sweat collected using a non-occlusive patch. After analyzing sweat samples collected from forearm, neck, and lower back areas, a total of 3140 sweat metabolites were detected across 342 LC-MS runs with 84 metabolites positively identified using a dansyl standard library. We see a location dependence characteristic of sweat composition, as well as significant metabolome differences between male and female sweat. This work showed the applicability of non-occlusive sample collection and CIL-LC-MS to study phenotypic differences as well as mapping locations on the skin. Chapter 4 demonstrates the use of non-occlusive sweat collection combined with CIL LC-MS to study lymphedema in a real world clinical application. Sweat was collected from diseased and healthy areas of lymphedema patients, and preliminary data revealed metabolome differences between these collection areas which were not present in the same areas of healthy individuals. This project is currently being expanded to include more lymphedema patients in order to confirm the sweat metabolome trends observed.

• Subjects / Keywords

  • Metabolomics
  • Chemical isotope labeling
  • LC-MS
  • Sweat
  • Sweat patch

• Graduation date

  Fall 2017

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/R31G0JB03

• 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.