Evidence map›Paper›PMID 41925694›Full record

ArticleInvestigative ophthalmology & visual science2026

Identification of Brimonidine as a Novel Substrate of Organic Cation Transporters OCT2 and MATE1 Expressed in Human Eye.

Charlotte Kölz, Claudia Neul, Ute Hofmann, Julia C Dressler, Daniela Süsskind, Bernd Wissinger, Matthias Schwab, Anne T Nies

Abstract read
In one paragraph

Article in Investigative ophthalmology & visual science, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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1 · What the graph read from it

What it found

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2 · The registry

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3 · Its place in the literature

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0 citing papers in PubMed.

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4 · The record

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5 · Who and what money

Authors and funding

8 authors.

Charlotte KölzDr. Margarete Fischer-Bosch Institute of Clinical Pharmacology, Stuttgart, and University of Tübingen, Tübingen, Germany.
Claudia NeulDr. Margarete Fischer-Bosch Institute of Clinical Pharmacology, Stuttgart, and University of Tübingen, Tübingen, Germany.
Ute HofmannDr. Margarete Fischer-Bosch Institute of Clinical Pharmacology, Stuttgart, and University of Tübingen, Tübingen, Germany.
Julia C DresslerDr. Margarete Fischer-Bosch Institute of Clinical Pharmacology, Stuttgart, and University of Tübingen, Tübingen, Germany.
Daniela SüsskindInstitute for Ophthalmic Research, Center for Ophthalmology, University of Tübingen, Tübingen, Germany.
Bernd WissingerInstitute for Ophthalmic Research, Center for Ophthalmology, University of Tübingen, Tübingen, Germany.
Matthias SchwabDr. Margarete Fischer-Bosch Institute of Clinical Pharmacology, Stuttgart, and University of Tübingen, Tübingen, Germany.
Anne T NiesDr. Margarete Fischer-Bosch Institute of Clinical Pharmacology, Stuttgart, and University of Tübingen, Tübingen, Germany.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

Purpose: Brimonidine, a selective α2-adrenergic agonist, is widely used in topical therapy for ocular hypertension or primary open-angle glaucoma. However, effective delivery is hindered by multiple ocular surface barriers. Because brimonidine is a cationic drug, we hypothesized that organic cation transporters (OCTs) and multidrug and toxin extrusion proteins (MATEs) are involved in brimonidine uptake in the human eye. This study aimed to determine if brimonidine is transported by OCT1, OCT2, OCT3, MATE1, and MATE2K and if the identified transporters are localized in anterior eye structures. Methods: Uptake studies were performed using HEK293 cells stably expressing OCT1, OCT2, OCT3, MATE1, and MATE2K. Intracellular brimonidine accumulation was analyzed by mass spectrometry. Immunohistochemistry of glaucomatous human eyes was used to localize relevant transporters in anterior ocular structures. Results: Brimonidine was transported by OCT2 and MATE1 but not by OCT1, OCT3, or MATE2K. Uptake was time- and concentration-dependent. Both OCT2 and MATE1 were expressed in the cornea, the conjunctiva, and the ciliary body. Conclusions: These results imply that OCT2 and MATE1 may play a role in brimonidine uptake into the human eye and may contribute to the interindividual variability of brimonidine concentrations and effects.

Indexed as

Adrenergic alpha-2 Receptor AgonistsBrimonidine TartrateGlaucoma, Open-AngleOrganic Cation Transport ProteinsHEK293 CellsHumansImmunohistochemistryMass SpectrometryOrganic Cation Transporter 2Adrenergic alpha-2 Receptor AgonistsBrimonidine TartrateOrganic Cation Transporter 2Organic Cation Transport ProteinsSLC22A2 protein, humanSLC47A1 protein, human

Identifiers

PMID41925694
PMCPMC13052447

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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.