Biomarkers serve as objective indicators of normal, diseased and therapeutic conditions to aid prediction, diagnosis and staging of diseases as well as monitoring and evaluating clinical responses to interventions. Metabolomics has emerged as a powerful holistic approach to assess physiological status of a biological system, and advances in metabolomics techniques promoted the discovery of biomarkers of wellness and disease. This dissertation presents the development of liquid chromatography-mass spectrometry (LC-MS) based metabolomics approaches to profile endogenous metabolites and monitor research subjects’ consumption of drugs. The analytical approaches were applied to discover potential plasma biomarkers that can help understanding and evaluating pulmonary rehabilitation (PR) exercise and osteopathic manipulative treatment (OMT) to chronic obstructive pulmonary disease (COPD). This dissertation is based on a pilot study, in which COPD patients were participants in a PR program where they performed exercises and either received OMT, sham OMT treatment, or no additional treatment. Prior to profiling endogenous metabolites, the first study described the development and validation of a LC-MS/MS method to screen fourteen non-steroidal anti-inflammatory drugs (NSAIDs) in plasma samples from these COPD patients, and data were compared to self-reported medication use assessed from questionnaires. The results showed that 24 of 26 subjects tested positive for at least one NSAID. However, only 3 participants self-reported NSAID drug use correctly. This work revealed the inaccuracy of self-reported medication information, suggesting that drug use monitoring by analytical approaches should be implemented as a routine practice to support clinical trials.Both untargeted and targeted metabolomics strategies were performed in this dissertation to assess biochemical alterations in levels of metabolites in blood plasma following PR exercise and OMT/sham/no additional treatment on COPD patients. The second study described an untargeted approach combining the power of an advanced LC-TOF-MS platform and both univariate and multivariate statistical analyses to identify potential biomarkers of the effect of exercise on the plasma metabolome. The most discriminating metabolites were identified as lipids, and most were free fatty acids, which can serve as biomarkers of exercise.In the third study, a targeted LC-MS/MS method was developed for quantification of 57 bioactive lipid mediators in human plasma samples drawn from COPD patient participants in PR with, or without extra OMT or sham treatment. Using the targeted approach, which was intended to provide a more comprehensive assessment of lipid mediators than prior publications, the responses of circulating oxylipins, endocannabinoids and polyunsaturated fatty acids (PUFAs) to PR exercise and OMT were assessed. The results demonstrated that PR exercise significantly increased PUFAs levels in the circulatory system of COPD patients and further induced the synthesis of downstream oxylipins including epoxides, diols, monohydroxy, and ketone metabolites within one hour post-exercise, but the impact faded over 72 hour post-exercise. Extra OMT and sham treatments were associated with minor reductions in the biochemical influence of PR exercise.
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