{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,30]],"date-time":"2026-09-30T21:27:39Z","timestamp":1790803659820,"version":"4.1.0"},"reference-count":105,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2025,12,26]],"date-time":"2025-12-26T00:00:00Z","timestamp":1766707200000},"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>The microbiota\u2013gut\u2013brain axis (MGBA) comprises a complex bidirectional communication network integrating neural, immune, metabolic, and endocrine pathways. Dopamine, traditionally viewed as a central neurotransmitter, also plays essential roles in the gastrointestinal (GI) tract, where it regulates motility, secretion, barrier homeostasis, and mucosal immunity. Growing evidence indicates that the gut microbiota significantly contributes to intestinal dopamine metabolism through specialized enzymatic pathways, particularly tyrosine decarboxylase in Enterococcus species and catechol dehydroxylase in Eggerthella species. These microbial reactions compete with host processes, alter dopaminergic tone, and degrade orally administered levodopa (L-DOPA), providing a mechanistic explanation for the variability in treatment response in Parkinson\u2019s disease (PD). Beyond PD, microbially mediated alterations in dopaminergic signaling have been implicated in mood disorders, neurodevelopmental conditions, metabolic dysfunction, and immune-mediated diseases. This review synthesizes current mechanistic and translational evidence on the dopamine\u2013microbiota interface, outlines microbial pathways shaping dopaminergic activity, and highlights therapeutic opportunities including microbiota modulation, dietary strategies, fecal microbiota transplantation, and targeted inhibitors of microbial dopamine metabolism. Understanding this interface offers a foundation for developing personalized approaches in neurogastroenterology and neuromodulatory therapies.<\/jats:p>","DOI":"10.3390\/ijms27010271","type":"journal-article","created":{"date-parts":[[2025,12,29]],"date-time":"2025-12-29T05:28:19Z","timestamp":1766986099000},"page":"271","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":19,"title":["Dopamine and the Gut Microbiota: Interactions Within the Microbiota\u2013Gut\u2013Brain Axis and Therapeutic Perspectives"],"prefix":"10.3390","volume":"27","author":[{"ORCID":"https:\/\/orcid.org\/0009-0000-2475-3646","authenticated-orcid":false,"given":"Aurelia Cristiana","family":"Barbu","sequence":"first","affiliation":[{"name":"Faculty of Medicine, \u201cCarol Davila\u201d University of Medicine and Pharmacy, 050474 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2874-1674","authenticated-orcid":false,"given":"Smaranda","family":"Stoleru","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, \u201cCarol Davila\u201d University of Medicine and Pharmacy, 050474 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Aurelian","family":"Zugravu","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, \u201cCarol Davila\u201d University of Medicine and Pharmacy, 050474 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6414-0841","authenticated-orcid":false,"given":"Elena","family":"Poenaru","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, \u201cCarol Davila\u201d University of Medicine and Pharmacy, 050474 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Adrian","family":"Dragomir","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, \u201cCarol Davila\u201d University of Medicine and Pharmacy, 050474 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3678-7584","authenticated-orcid":false,"given":"Mihnea","family":"Costescu","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, \u201cCarol Davila\u201d University of Medicine and Pharmacy, 050474 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3215-8892","authenticated-orcid":false,"given":"Sorina Maria","family":"Aurelian","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, \u201cCarol Davila\u201d University of Medicine and Pharmacy, 050474 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yara","family":"Shhab","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, \u201cCarol Davila\u201d University of Medicine and Pharmacy, 050474 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Clara Maria","family":"Stoleru","sequence":"additional","affiliation":[{"name":"Faculty of Medical Engineering, National University of Science and Technology Politehnica Bucharest, 060042 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Oana Andreia","family":"Coman","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, \u201cCarol Davila\u201d University of Medicine and Pharmacy, 050474 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ion","family":"Fulga","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, \u201cCarol Davila\u201d University of Medicine and Pharmacy, 050474 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,12,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Xu, J., and Lu, Y. 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