{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,28]],"date-time":"2026-08-28T04:02:21Z","timestamp":1787889741669,"version":"build-2784847793"},"reference-count":59,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2025,5,10]],"date-time":"2025-05-10T00:00:00Z","timestamp":1746835200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Parkinson\u2019s disease (PD) progression appears closely tied to gut microbiota alterations, with microbial metabolites potentially influencing neurodegeneration. This pilot study employed GC-MS and LC-MS\/MS to analyze the urinary levels of gut-derived metabolites\u2014including succinic acid, p-hydroxyphenylacetic acid, homovanillic acid (HVA), vanillylmandelic acid (VMA), adipic acid, and trimethylamine N-oxide (TMAO)\u2014in 20 PD patients versus 20 age-matched controls. The key findings revealed that PD patients exhibited significantly elevated succinic acid (p = 0.0018) and HVA (p = 0.0002) levels alongside reduced TMAO (p = 1.65 \u00d7 10\u22125). Notably, succinic acid showed an inverse correlation with disease severity (Hoehn and Yahr scale: r = \u22120.63; p = 0.0028), while TMAO demonstrated a strong positive association (r = 0.81; p = 0.00001). The elevated HVA, a dopamine metabolite, may serve as a potential biomarker for monitoring levodopa treatment efficacy. These results suggest that gut microbiota metabolites contribute to PD pathogenesis, with TMAO and succinic acid emerging as promising biomarkers for tracking disease progression. This study highlights the clinical potential of non-invasive urinary metabolite profiling using GC-MS and LC-MS\/MS techniques. However, further investigation through larger-scale studies is needed to confirm these findings and elucidate the underlying mechanisms connecting gut microbiota dysbiosis to PD neurodegeneration.<\/jats:p>","DOI":"10.3390\/ijms26104575","type":"journal-article","created":{"date-parts":[[2025,5,12]],"date-time":"2025-05-12T10:58:07Z","timestamp":1747047487000},"page":"4575","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["The Determination of Trimethylamine N-Oxide and Organic Acids Connected with Gut Microbiota in the Urine of Parkinson\u2019s Disease Patients: A Pilot Study"],"prefix":"10.3390","volume":"26","author":[{"ORCID":"https:\/\/orcid.org\/0009-0006-3825-522X","authenticated-orcid":false,"given":"Paulina","family":"G\u0105tarek","sequence":"first","affiliation":[{"name":"Institute of General and Ecological Chemistry, Faculty of Chemistry, Lodz University of Technology, 116 Zeromskiego Street, 90-924 Lodz, Poland"},{"name":"CONEM Poland Chemistry and Nutrition Research Group, Lodz University of Technology, 90-924 Lodz, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4540-0932","authenticated-orcid":false,"given":"Ma\u0142gorzata","family":"Pawe\u0142czyk","sequence":"additional","affiliation":[{"name":"Department of Neurology and Stroke, Medical University of Lodz, 90-549 Lodz, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1617-2352","authenticated-orcid":false,"given":"Barbara","family":"Bobrowska-Korczaka","sequence":"additional","affiliation":[{"name":"Department of Toxicology and Food Science, Faculty of Pharmacy, Medical University of Warsaw, Banacha 1 Street, 02-097 Warsaw, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2567-4453","authenticated-orcid":false,"given":"Joanna","family":"Giebu\u0142towicz","sequence":"additional","affiliation":[{"name":"Department of Drug Chemistry, Pharmaceutical and Biomedical Analysis, Faculty of Pharmacy, Medical University of Warsaw, Banacha 1, 02-097 Warsaw, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1305-1494","authenticated-orcid":false,"given":"Andrzej","family":"G\u0142\u0105bi\u0144ski","sequence":"additional","affiliation":[{"name":"Department of Neurology and Stroke, Medical University of Lodz, 90-549 Lodz, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5106-4667","authenticated-orcid":false,"given":"Joanna","family":"Ka\u0142u\u017cna-Czapli\u0144ska","sequence":"additional","affiliation":[{"name":"Institute of General and Ecological Chemistry, Faculty of Chemistry, Lodz University of Technology, 116 Zeromskiego Street, 90-924 Lodz, Poland"},{"name":"CONEM Poland Chemistry and Nutrition Research Group, Lodz University of Technology, 90-924 Lodz, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,5,10]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Voigt, R.M., Wang, Z., Brown, J.M., Engen, P.A., Naqib, A., Goetz, C.G., Hall, D.A., Metman, L.V., Shaikh, M., and Forsyth, C.B. 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