Biological relationship between Parkinson's disease and gallstone disease

Compelling evidence indicates a significant connection between dysfunction of the gastrointestinal tract, the gut microbiome, and Parkinson's disease (PD), which aligns with the notion of the "gut-brain axis". While the exact mechanisms involved in gut-brain interactions are still not fully understood, the high incidence of gastrointestinal symptoms during the early stages of PD aids in the development of diagnostic biomarkers and prospective disease-modifying therapies. Importantly, a number of studies have revealed a possible association between gallstone disease (GD) and PD; nevertheless, the exploration of diverse risk factors and the theory suggesting that the onset of PD might be associated with GD requires further investigation. This review aims to explore the evidence that connects alterations in GD with PD, emphasizing mechanisms that promote gut dysbiosis, the gut-brain connection, changes in lipid profiles, genetic and dietary influences, as well as neuroinflammation. Furthermore, we assess the potential implementation of innovative therapeutic strategies, including probiotic treatments and gut microbiota transplantation, in patients with PD. Although the evidence supports an association between PD and GD, causality remains to be established. Prospective cohort studies are needed to determine whether gallstones represent a prodromal marker or a causal risk factor for PD, and to validate these pathways as novel diagnostic and therapeutic targets for PD.