Comparison of Metabolites and Gut Microbes between Patients with Parkinson's Disease and Healthy Individuals-A Pilot Clinical Observational Study (STROBE Compliant).

Introduction: Even if levodopa, dopamine agonists, and others are used for patients with Parkinson's disease, the effect is not sustained, and side effects such as motor fluctuation and dyskinesia are more likely to appear as the dose increases. Thus, new approaches for managing Parkinson's disease are needed. This study aimed to compare the metabolites and gut microbes between patients with Parkinson's disease and healthy individuals.

Methods: This was an observational study with a case-control design. Metabolite and gut microbial analyses were performed using blood and stool samples collected from the subjects.

Results: Among the metabolites, the acetate, citrate, methionine, and trimethylamine levels were significantly different between the two groups. In the gut microbes, abundance of , , , , , and were also significantly different between the two groups.

Discussion: Metabolites are the products of gut microbes. Therefore, when the gut microbes change, the metabolites change accordingly. Metabolites and gut microbes that were significantly different between the two groups were mostly those involved in lipid and glucose metabolism. Our data may be helpful for the development of new drugs targeting metabolites and gut microbes through large-scale studies in the future.