Abstract |
Tebipenem pivoxil (TBPM-PI) is an oral carbapenem antibiotic for treating otolaryngologic and respiratory infections in pediatric patients. This agent is a prodrug to improve intestinal absorption of TBPM, an active form, and an absorption rate of TBPM-PI is higher than those of other prodrug-type β- lactam antibiotics. In the present study, we hypothesized that a certain mechanism other than simple diffusion is involved in the process of improved intestinal absorption of TBPM-PI and examined the mechanism. TBPM-PI uptake by Caco-2 cells was decreased by ATP-depletion and lowering the temperature to 4 °C, suggesting the contribution of carrier-mediated transport mechanisms. This uptake was partially decreased by ACE inhibitors, and the reduction of the absorption by captopril was observed by in vivo study and in situ single-pass intestinal perfusion study in rat, supporting the contribution of influx transporters. Since some ACE inhibitors and β- lactam antibiotics are reported to be substrates of PEPT and OATP families, we measured transporting activity of TBPM-PI by intestinally expressed transporters, PEPT1, OATP1A2, and OATP2B1. As a result, significant transport activities were observed by both OATP1A2 and OATP2B1 but not by PEPT1. Interestingly, pH dependence of TBPM-PI transports was different between OATP1A2 and OATP2B1, showing highest activity by OATP1A2 at pH 6.5, while OATP2B1-mediated uptake was higher at neutral and weak alkaline pH. OATP1A2 exhibited higher affinity for TBPM-PI (K(m) = 41.1 μM) than OATP2B1 (K(m) > 1 mM) for this agent. These results suggested that TBPM-PI has high intestinal apical membrane permeability due to plural intestinal transport routes, including the uptake transporters such as OATP1A2 and OATP2B1 as well as simple diffusion.
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Authors | Kazuhiko Kato, Yoshiyuki Shirasaka, Erika Kuraoka, Akihiro Kikuchi, Maki Iguchi, Hisashi Suzuki, Shigeki Shibasaki, Tohru Kurosawa, Ikumi Tamai |
Journal | Molecular pharmaceutics
(Mol Pharm)
Vol. 7
Issue 5
Pg. 1747-56
(Oct 04 2010)
ISSN: 1543-8392 [Electronic] United States |
PMID | 20735088
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
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Chemical References |
- Anti-Bacterial Agents
- Carbapenems
- Organic Anion Transporters
- Peptide Transporter 1
- SLC15A1 protein, human
- SLCO1A2 protein, human
- SLCO2B1 protein, human
- Symporters
- Captopril
- tebipenem
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Topics |
- Administration, Oral
- Animals
- Anti-Bacterial Agents
(administration & dosage, pharmacokinetics)
- Biological Transport, Active
- Caco-2 Cells
- Captopril
(pharmacology)
- Carbapenems
(administration & dosage, pharmacokinetics)
- Female
- Humans
- Hydrogen-Ion Concentration
- Intestinal Absorption
(drug effects, physiology)
- Kinetics
- Male
- Oocytes
(metabolism)
- Organic Anion Transporters
(metabolism)
- Peptide Transporter 1
- Rats
- Rats, Sprague-Dawley
- Symporters
(metabolism)
- Xenopus
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