ArticleInternational ophthalmology2021
Glaucoma patients have an increased level of trimethylamine, a toxic product of gut bacteria, in the aqueous humor: a pilot study.
Article in International ophthalmology, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 19 papers, 1 of them a synthesis that pooled it.
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Who cites it
19 citing papers in PubMed, 1 synthesis or guideline pooled it, 27 citations in OpenAlex.
- Metabolomics in Primary Open Angle Glaucoma: A Systematic Review and Meta-Analysis.Frontiers in neuroscience · 2022Pooled it
- An Update and Overview of the Ocular and Extraocular Microbiome and Its Impact on Ophthalmic Care.Advances in therapy · 2026Review
- Transcending genome-wide association studies to create useful multi-omic views of glaucoma.Progress in retinal and eye research · 2026Review
- Ocular immune homeostasis-mechanisms of precise regulation through coordination of the eye, visual system and beyond: a narrative review.Annals of eye science · 2026Article
- The Ocular and Gut Microbiome Axis in Understanding Glaucoma: A Systematic Review.Journal of clinical medicine · 2026Review
- Role of gut microbiomes in different ocular pathologies: A systematic review.World journal of gastrointestinal pathophysiology · 2025Article
- Primary open-angle glaucoma: a perspective from plasma metabolomics.Expert review of molecular diagnostics · 2025Review
- Microbiome-based therapeutics for ocular diseases.Clinical & experimental optometry · 2025Review
- The Ocular Microbiome: Micro-Steps Towards Macro-Shift in Targeted Treatment? A Comprehensive Review.Microorganisms · 2024Review
- The Role of Gut Microbiota in the Pathogenesis of Glaucoma: Evidence from Bibliometric Analysis and Comprehensive Review.Bioengineering (Basel, Switzerland) · 2024Review
- Microbiome as an endocrine organ and its relationship with eye diseases: Effective factors and new targeted approaches.World journal of gastrointestinal pathophysiology · 2024Review
- From Gut to Eye: Exploring the Role of Microbiome Imbalance in Ocular Diseases.Journal of clinical medicine · 2024Review
- The gut-eye axis: the retinal/ocular degenerative diseases and the emergent therapeutic strategies.Frontiers in cellular neuroscience · 2024Review
- The correlation between primary open-angle glaucoma (POAG) and gut microbiota: a pilot study towards predictive, preventive, and personalized medicine.The EPMA journal · 2023Article
- Targeting the Gut-Eye Axis: An Emerging Strategy to Face Ocular Diseases.International journal of molecular sciences · 2023Review
- Mucosal immunology of the ocular surface.Mucosal immunology · 2022Review
- Trimethylamine N-Oxide, a Gut Microbiota-Derived Metabolite, Is Associated with Cardiovascular Risk in Psoriasis: A Cross-Sectional Pilot Study.Dermatology and therapy · 2021Article
- Microbiota and Ocular Diseases.Frontiers in cellular and infection microbiology · 2021Review
- Causal Links between Gut Microbiota, Blood Metabolites, Immune Cells, Inflammatory Proteins, and Myopia: A Mendelian Randomization Study.Ophthalmology scienceArticle
Corrections and comments
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Authors and funding
8 authors at 2 institutions in 1 country.
Funding
Abstract
purposeAnimal studies suggest that gut bacteria metabolites are involved in regulation of intraocular pressure or development of glaucoma. However, clinical data are lacking. Here, we wanted to compare level of trimethylamine (TMA), an uremic toxin produced by gut bacteria, along with betaine and trimethylamine N-oxide (TMAO), a substrate and a product of its metabolism, in the aqueous humor and in plasma of patients with glaucoma and their controls.
methodsTwenty patients were selected for cataract phacoemulsification, and 20 patients selected for phacotrabeculectomy were enrolled in the study. Patients were matched with controls on systemic diseases and estimated glomerular filtration rate. Blood samples were collected in the preoperative suite, whereas aqueous humor samples were collected as the first step of both procedures. Subsequently, level of betaine, TMA and TMAO was analyzed by means of chromatography.
resultsIn the aqueous humor, level of TMA, but not betaine or TMAO, was significantly higher in the phacotrabeculectomy group than in the phacoemulsification group. Plasma level of betaine, TMA and TMAO was similar between groups. In both groups, level of betaine and TMA, but not TMAO, was significantly higher in plasma than in the aqueous humor.
conclusionTMA, but not TMAO or betaine level, is increased in the aqueous humor of patients with glaucoma. TMA might play a role in pathogenesis of glaucoma; however, prospective studies are needed to confirm our findings.
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