Exposomics to unravel Parkinson’s disease etiology

Parkinson’s disease (PD) is a complex and multifaceted illness possibly linked to many environmental factors. This thesis contributes to the existing knowledge on the role of environmental exposures in PD etiology within a prospective cohort, utilizing blood samples collected prior to PD diagnosis. The findings of this thesis confirm a protective effect of coffee consumption on PD risk, in line with previous studies. This effect is predominantly attributed to caffeine and its primary metabolites. Additionally, chronic systemic inflammation induced by the bacterial product, endotoxin, has been associated with PD, and the metabolic profiles of microbial metabolites show variations influenced by individual characteristics. These results underscore the involvement of the gut in the pathogenesis of PD. However, the roles of metal exposures remain elusive, with no definitive reports from either the existing literature or analyses within this thesis. This thesis emphasizes the characterization of internal exposures through untargeted metabolomics. Leveraging this advanced analytic platform enables the detection of a broad spectrum of exposure biomarkers, encompassing both known and currently unidentified chemicals. The integration of metabolomics into epidemiological research facilitates the identification of body burden of environmental agents and their relevance with biological outcomes.