ArticlePharmaceutical research2009
The antiepileptic drug topiramate is a substrate for human P-glycoprotein but not multidrug resistance proteins.
Article in Pharmaceutical research, 2009. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 10 papers, 1 of them a synthesis that pooled it.
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Who cites it
10 citing papers in PubMed, 1 synthesis or guideline pooled it, 50 citations in OpenAlex.
- New use for an old drug: quinidine in KCNT1-related epilepsy therapy.Neurological sciences : official journal of the Italian Neurological Society and of the Italian Society of Clinical Neurophysiology · 2023Pooled it
- Drug-resistant Epilepsy: Which Drugs are Substrates of P-glycoprotein and Which are Not?Current neuropharmacology · 2026Review
- Pluronic P85 decreases the delivery of phenytoin to the brain in drug-resistant rats with P-glycoprotein overexpressed chronic mesial temporal lobe epilepsy.IBRO neuroscience reports · 2023Article
- Disease-Induced Modulation of Drug Transporters at the Blood-Brain Barrier Level.International journal of molecular sciences · 2021Review
- A face-to-face comparison of claudin-5 transduced human brain endothelial (hCMEC/D3) cells with porcine brain endothelial cells as blood-brain barrier models for drug transport studies.Fluids and barriers of the CNS · 2020Article
- Similar Safety Profile of the Enantiomeric N-Aminoalkyl Derivatives ofMolecules (Basel, Switzerland) · 2019Article
- Drug-Resistant Epilepsy: Multiple Hypotheses, Few Answers.Frontiers in neurology · 2017Review
- Pharmacogenetics of chronic pain and its treatment.Mediators of inflammation · 2013Review
- (R)-[11C]verapamil PET studies to assess changes in P-glycoprotein expression and functionality in rat blood-brain barrier after exposure to kainate-induced status epilepticus.BMC medical imaging · 2011Article
- Differences in the expression of endogenous efflux transporters in MDR1-transfected versus wildtype cell lines affect P-glycoprotein mediated drug transport.British journal of pharmacology · 2010Article
Corrections and comments
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Authors and funding
4 authors at 2 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
purposeResistance to antiepileptic drugs (AEDs) is the major problem in the treatment of epilepsy. One of the candidate mechanisms of pharmacoresistance is the limitation of AED access to the seizure focus by overexpression of efflux transporters, including P-glycoprotein (Pgp) and multidrug resistance proteins (MRPs).In this respect, it is important to know which AEDs are substrates for such drug transporters in humans.
methodsIn the present study, we used polarized kidney cell lines (LLC, MDCK) transfected with human drug transporters (Pgp, MRP1, MRP2 or MRP5) to evaluate whether the AED topiramate is a substrate for any of these transporters. Known Pgp and MRP substrates were used for comparison.
resultsBasolateral-to-apical transport of topiramate, which could be counteracted with the Pgp inhibitor, tariquidar, was determined in Pgp overexpressing LLC cells, whereas topiramate was not transported by any of the MRPs. A comparison with previous experiments in the same transport assay showed that topiramate exhibited the most pronounced Pgp-mediated efflux transport among the AEDS that have been studied as yet.
conclusionsThus, these data indicate that brain levels of topiramate may be affected by overexpression of Pgp as determined in patients with intractable epilepsy.
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