ArticleNature communications2019
Gut bacterial tyrosine decarboxylases restrict levels of levodopa in the treatment of Parkinson's disease.
Article in Nature communications, 2019. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 275 papers, 4 of them syntheses that pooled it.
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Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
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Who cites it
275 citing papers in PubMed, 4 syntheses or guidelines pooled it, 495 citations in OpenAlex.
- Machine learning-based meta-analysis reveals gut microbiome alterations associated with Parkinson's disease.Nature communications · 2025Pooled it
- Safety and efficacy of fecal microbiota transplantation in the treatment of Parkinson's disease: a systematic review of clinical trials.Frontiers in neuroscience · 2025Pooled it
- Gastrointestinal Issues in Depression, Anxiety, and Neurodegenerative Diseases: A Systematic Review on Pathways and Clinical Targets Implications.CNS & neurological disorders drug targets · 2024Pooled it
- What Are the Key Gut Microbiota Involved in Neurological Diseases? A Systematic Review.International journal of molecular sciences · 2022Pooled it
- Exploring the role of gut microbiota in potential mechanism of ketogenic diet in alleviating Parkinson's disease symptoms.Frontiers in neuroscience · 2026Trial
- An open label, non-randomized study assessing a prebiotic fiber intervention in a small cohort of Parkinson's disease participants.Nature communications · 2023Trial
- Extracellular vesicles and their RNA cargo facilitate bidirectional cross-kingdom communication between human and bacterial cells.Gut microbes · 2026Article
- The microbiota at the interface of environmental toxicants and the brain.Cell metabolism · 2026Review
- Review
- Drug-microbiome-host interactions: antimicrobial effects of non-antibiotic compounds.Nature reviews. Gastroenterology & hepatology · 2026Review
- The microbiome regulates host metabolic health and diseases through microbial enzymes.Nature reviews. Gastroenterology & hepatology · 2026Review
- Oxygen homeostasis: new insight of gut microbiota-host interactions.NPJ biofilms and microbiomes · 2026Review
- Advancing the Treatment of Motor Fluctuations in Parkinson's Disease with a Next-Generation Levodopa/Carbidopa Formulation.Neurology and therapy · 2026Review
- Effects of supplementing concentrates with different energy levels on growth performance, blood indicators, and fecal microbiota of Mongolian horses in late gestation.BMC veterinary research · 2026Article
- Enterococcus hirae QT4713-derived dopamine ameliorates intestinal inflammation and MPTP-induced Parkinson's disease in mice.NPJ Parkinson's disease · 2026Article
- A drug-microbiome-drug interaction impacts co-prescribed medications for Parkinson's disease.Nature microbiology · 2026Article
- Gut-Brain Signaling in Parkinson's Disease: A Narrative Review.International journal of molecular sciences · 2026Review
- Gut microbial metabolic disorder in depression: insights from computational modeling and mediation analysis.BMC microbiology · 2026Article
- Fighting for Chemicals: Pharmacophagy-Induced Contest Behaviour and Its Molecular Signatures in a Sawfly.Molecular ecology · 2026Article
- Evodiamine alleviates MPTP-induced Parkinson's disease in mice by regulating gut microbiota and suppressing TLR4/MyD88/NF-kB pathway.Scientific reports · 2026Article
215 more citing papers are in PubMed but not listed here.
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Authors and funding
7 authors at 3 institutions in 3 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Human gut microbiota senses its environment and responds by releasing metabolites, some of which are key regulators of human health and disease. In this study, we characterize gut-associated bacteria in their ability to decarboxylate levodopa to dopamine via tyrosine decarboxylases. Bacterial tyrosine decarboxylases efficiently convert levodopa to dopamine, even in the presence of tyrosine, a competitive substrate, or inhibitors of human decarboxylase. In situ levels of levodopa are compromised by high abundance of gut bacterial tyrosine decarboxylase in patients with Parkinson's disease. Finally, the higher relative abundance of bacterial tyrosine decarboxylases at the site of levodopa absorption, proximal small intestine, had a significant impact on levels of levodopa in the plasma of rats. Our results highlight the role of microbial metabolism in drug availability, and specifically, that abundance of bacterial tyrosine decarboxylase in the proximal small intestine can explain the increased dosage regimen of levodopa treatment in Parkinson's disease patients.
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Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.