1
|
Watari R, Tamura N, Yoshida S, Kido Y, Matsuzaki T. Minimal involvement of P-gp and BCRP in oral absorption of ensitrelvir, an oral SARS-CoV-2 3C-like protease inhibitor, in a non-clinical investigation. J Pharm Sci 2024:S0022-3549(24)00232-6. [PMID: 38885812 DOI: 10.1016/j.xphs.2024.06.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2024] [Revised: 06/12/2024] [Accepted: 06/12/2024] [Indexed: 06/20/2024]
Abstract
P-glycoprotein (P-gp) and breast cancer resistance protein (BCRP) are important transporters causing drug-drug interaction (DDI). Here, we investigated the involvement of P-gp and BCRP in the oral absorption of ensitrelvir in non-clinical studies and estimated the DDI risk mediated by P-gp and BCRP inhibition in humans. Although ensitrelvir is an in vitro P-gp and BCRP substrate, it demonstrated high bioavailability in rats and monkeys after oral administration. Plasma exposures of ensitrelvir following oral administration were comparable in wild type (WT) and Bcrp (-/-) mice. On the other hand, the area under the plasma concentration-time curve (AUC) ratio of ensitrelvir in the Mdr1a/1b (-/-) mice to the WT mice was 1.92, indicating that P-gp, but not BCRP, was involved in the oral absorption of ensitrelvir. Based on our previous retrospective analyses, such a low AUC ratio (<3) in the Mdr1a/1b (-/-) mice indicates a minimal impact of P-gp on the oral absorption in humans. In conclusion, our studies demonstrate that the involvement of both P-gp and BCRP in the oral absorption of ensitrelvir is minimal, and suggest that ensitrelvir has a low risk for DDIs mediated by P-gp and BCRP inhibition in humans.
Collapse
Affiliation(s)
- Ryosuke Watari
- Laboratory for Drug Discovery and Development, Shionogi & Co., Ltd..
| | - Naomi Tamura
- Laboratory for Drug Discovery and Development, Shionogi & Co., Ltd
| | - Shinpei Yoshida
- Laboratory for Drug Discovery and Development, Shionogi & Co., Ltd
| | - Yasuto Kido
- Laboratory for Drug Discovery and Development, Shionogi & Co., Ltd
| | | |
Collapse
|
2
|
Eltanameli B, Piñeiro-Llanes J, Cristofoletti R. Recent advances in cell-based in vitro models for predicting drug permeability across brain, intestinal, and pulmonary barriers. Expert Opin Drug Metab Toxicol 2024; 20:439-458. [PMID: 38850058 DOI: 10.1080/17425255.2024.2366390] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2024] [Accepted: 06/06/2024] [Indexed: 06/09/2024]
Abstract
INTRODUCTION Recent years have witnessed remarkable progress in the development of cell-based in vitro models aimed at predicting drug permeability, particularly focusing on replicating the barrier properties of the blood-brain barrier (BBB), intestinal epithelium, and lung epithelium. AREA COVERED This review provides an overview of 2D in vitro platforms, including monocultures and co-culture systems, highlighting their respective advantages and limitations. Additionally, it discusses tools and techniques utilized to overcome these limitations, paving the way for more accurate predictions of drug permeability. Furthermore, this review delves into emerging technologies, particularly microphysiological systems (MPS), encompassing static platforms such as organoids and dynamic platforms like microfluidic devices. Literature searches were performed using PubMed and Google Scholar. We focus on key terms such as in vitro permeability models, MPS, organoids, intestine, BBB, and lungs. EXPERT OPINION The potential of these MPS to mimic physiological conditions more closely offers promising avenues for drug permeability assessment. However, transitioning these advanced models from bench to industry requires rigorous validation against regulatory standards. Thus, there is a pressing need to validate MPS to industry and regulatory agency standards to exploit their potential in drug permeability prediction fully. This review underscores the importance of such validation processes to facilitate the translation of these innovative technologies into routine pharmaceutical practice.
Collapse
Affiliation(s)
- Bassma Eltanameli
- Center for Pharmacometrics & Systems Pharmacology, Department of Pharmaceutics, College of Pharmacy, University of Florida, Orlando, FL, USA
- Department of Pharmaceutics, Faculty of Pharmacy, Mansoura University, Mansoura, Egypt
| | - Janny Piñeiro-Llanes
- Center for Pharmacometrics & Systems Pharmacology, Department of Pharmaceutics, College of Pharmacy, University of Florida, Orlando, FL, USA
| | - Rodrigo Cristofoletti
- Center for Pharmacometrics & Systems Pharmacology, Department of Pharmaceutics, College of Pharmacy, University of Florida, Orlando, FL, USA
| |
Collapse
|
3
|
Colclough N, Alluri RV, Tucker JW, Gozalpour E, Li D, Du H, Li W, Harlfinger S, O'Neill DJ, Sproat GG, Chen K, Yan Y, McGinnity DF. Utilizing a Dual Human Transporter MDCKII-MDR1-BCRP Cell Line to Assess Efflux at the Blood Brain Barrier. Drug Metab Dispos 2024; 52:95-105. [PMID: 38071533 DOI: 10.1124/dmd.123.001476] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Revised: 10/24/2023] [Accepted: 11/27/2023] [Indexed: 12/22/2023] Open
Abstract
To facilitate the design of drugs readily able to cross the blood brain barrier (BBB), a Madin-Darby canine kidney (MDCK) cell line was established that over expresses both P-glycoprotein (Pgp) and breast cancer resistance protein (BCRP), the main human efflux transporters of the BBB. Proteomics analyses indicate BCRP is expressed at a higher level than Pgp in this cell line. This cell line shows good activity for both transporters [BCRP substrate dantrolene efflux ratio (ER) 16.3 ± 0.9, Pgp substrate quinidine ER 27.5 ± 1.2], and use of selective transporter inhibitors enables an assessment of the relative contributions to overall ERs. The MDCKII-MDR1-BCRP ER negatively correlates with rat unbound brain/unbound plasma ratio, Kpuu Highly brain penetrant compounds with rat Kpuu ≥ 0.3 show ERs ≤ 2 in the MDCKII-MDR1-BCRP assay while compounds predominantly excluded from the brain, Kpuu ≤ 0.05, demonstrate ERs ≥ 20. A subset of compounds with MDCKII-MDR1-BCRP ER < 2 and rat Kpuu < 0.3 were shown to be substrates of rat Pgp using a rat transfected cell line, MDCKII-rMdr1a. These compounds also showed ERs > 2 in the human National Institutes of Health (NIH) MDCKI-MDR1 (high Pgp expression) cell line, which suggests that they are weak human Pgp substrates. Characterization of 37 drugs targeting the central nervous system in the MDCKII-MDR1-BCRP efflux assay show 36 have ERs < 2. In drug discovery, use of the MDCKII-MDR1-BCRP in parallel with the NIH MDCKI-MDR1 cell line is useful for identification of compounds with high brain penetration. SIGNIFICANCE STATEMENT: A single cell line that includes both the major human efflux transporters of the blood brain barrier (MDCKII-MDR1-BCRP) has been established facilitating the rapid identification of efflux substrates and enabling the design of brain penetrant molecules. Efflux ratios using this cell line demonstrate a clear relationship with brain penetration as defined by rat brain Kpuu.
Collapse
Affiliation(s)
- Nicola Colclough
- DMPK, Oncology R & D, AstraZeneca, Cambridge, United Kingdom (N.C., J.W.T., E.G., S.H., D.F.M.); Clinical Pharmacology and Safety Sciences, BioPharmaceuticals R&D, AstraZeneca, Cambridge, United Kingdom (R.V.A.); DMPK, Pharmaron, Beijing, China (D.L., H.D., W.L.); Discovery Sciences, Biopharmaceuticals R&D, AstraZeneca, Cambridge, United Kingdom (D.J.O., G.G.S.); and DMPK Asia, Oncology R & D, AstraZeneca, Shanghai, China (K.C., Y.Y.)
| | - Ravindra V Alluri
- DMPK, Oncology R & D, AstraZeneca, Cambridge, United Kingdom (N.C., J.W.T., E.G., S.H., D.F.M.); Clinical Pharmacology and Safety Sciences, BioPharmaceuticals R&D, AstraZeneca, Cambridge, United Kingdom (R.V.A.); DMPK, Pharmaron, Beijing, China (D.L., H.D., W.L.); Discovery Sciences, Biopharmaceuticals R&D, AstraZeneca, Cambridge, United Kingdom (D.J.O., G.G.S.); and DMPK Asia, Oncology R & D, AstraZeneca, Shanghai, China (K.C., Y.Y.)
| | - James W Tucker
- DMPK, Oncology R & D, AstraZeneca, Cambridge, United Kingdom (N.C., J.W.T., E.G., S.H., D.F.M.); Clinical Pharmacology and Safety Sciences, BioPharmaceuticals R&D, AstraZeneca, Cambridge, United Kingdom (R.V.A.); DMPK, Pharmaron, Beijing, China (D.L., H.D., W.L.); Discovery Sciences, Biopharmaceuticals R&D, AstraZeneca, Cambridge, United Kingdom (D.J.O., G.G.S.); and DMPK Asia, Oncology R & D, AstraZeneca, Shanghai, China (K.C., Y.Y.)
| | - Elnaz Gozalpour
- DMPK, Oncology R & D, AstraZeneca, Cambridge, United Kingdom (N.C., J.W.T., E.G., S.H., D.F.M.); Clinical Pharmacology and Safety Sciences, BioPharmaceuticals R&D, AstraZeneca, Cambridge, United Kingdom (R.V.A.); DMPK, Pharmaron, Beijing, China (D.L., H.D., W.L.); Discovery Sciences, Biopharmaceuticals R&D, AstraZeneca, Cambridge, United Kingdom (D.J.O., G.G.S.); and DMPK Asia, Oncology R & D, AstraZeneca, Shanghai, China (K.C., Y.Y.)
| | - Danxi Li
- DMPK, Oncology R & D, AstraZeneca, Cambridge, United Kingdom (N.C., J.W.T., E.G., S.H., D.F.M.); Clinical Pharmacology and Safety Sciences, BioPharmaceuticals R&D, AstraZeneca, Cambridge, United Kingdom (R.V.A.); DMPK, Pharmaron, Beijing, China (D.L., H.D., W.L.); Discovery Sciences, Biopharmaceuticals R&D, AstraZeneca, Cambridge, United Kingdom (D.J.O., G.G.S.); and DMPK Asia, Oncology R & D, AstraZeneca, Shanghai, China (K.C., Y.Y.)
| | - Hongwen Du
- DMPK, Oncology R & D, AstraZeneca, Cambridge, United Kingdom (N.C., J.W.T., E.G., S.H., D.F.M.); Clinical Pharmacology and Safety Sciences, BioPharmaceuticals R&D, AstraZeneca, Cambridge, United Kingdom (R.V.A.); DMPK, Pharmaron, Beijing, China (D.L., H.D., W.L.); Discovery Sciences, Biopharmaceuticals R&D, AstraZeneca, Cambridge, United Kingdom (D.J.O., G.G.S.); and DMPK Asia, Oncology R & D, AstraZeneca, Shanghai, China (K.C., Y.Y.)
| | - Wei Li
- DMPK, Oncology R & D, AstraZeneca, Cambridge, United Kingdom (N.C., J.W.T., E.G., S.H., D.F.M.); Clinical Pharmacology and Safety Sciences, BioPharmaceuticals R&D, AstraZeneca, Cambridge, United Kingdom (R.V.A.); DMPK, Pharmaron, Beijing, China (D.L., H.D., W.L.); Discovery Sciences, Biopharmaceuticals R&D, AstraZeneca, Cambridge, United Kingdom (D.J.O., G.G.S.); and DMPK Asia, Oncology R & D, AstraZeneca, Shanghai, China (K.C., Y.Y.)
| | - Stephanie Harlfinger
- DMPK, Oncology R & D, AstraZeneca, Cambridge, United Kingdom (N.C., J.W.T., E.G., S.H., D.F.M.); Clinical Pharmacology and Safety Sciences, BioPharmaceuticals R&D, AstraZeneca, Cambridge, United Kingdom (R.V.A.); DMPK, Pharmaron, Beijing, China (D.L., H.D., W.L.); Discovery Sciences, Biopharmaceuticals R&D, AstraZeneca, Cambridge, United Kingdom (D.J.O., G.G.S.); and DMPK Asia, Oncology R & D, AstraZeneca, Shanghai, China (K.C., Y.Y.)
| | - Daniel J O'Neill
- DMPK, Oncology R & D, AstraZeneca, Cambridge, United Kingdom (N.C., J.W.T., E.G., S.H., D.F.M.); Clinical Pharmacology and Safety Sciences, BioPharmaceuticals R&D, AstraZeneca, Cambridge, United Kingdom (R.V.A.); DMPK, Pharmaron, Beijing, China (D.L., H.D., W.L.); Discovery Sciences, Biopharmaceuticals R&D, AstraZeneca, Cambridge, United Kingdom (D.J.O., G.G.S.); and DMPK Asia, Oncology R & D, AstraZeneca, Shanghai, China (K.C., Y.Y.)
| | - Graham G Sproat
- DMPK, Oncology R & D, AstraZeneca, Cambridge, United Kingdom (N.C., J.W.T., E.G., S.H., D.F.M.); Clinical Pharmacology and Safety Sciences, BioPharmaceuticals R&D, AstraZeneca, Cambridge, United Kingdom (R.V.A.); DMPK, Pharmaron, Beijing, China (D.L., H.D., W.L.); Discovery Sciences, Biopharmaceuticals R&D, AstraZeneca, Cambridge, United Kingdom (D.J.O., G.G.S.); and DMPK Asia, Oncology R & D, AstraZeneca, Shanghai, China (K.C., Y.Y.)
| | - Kan Chen
- DMPK, Oncology R & D, AstraZeneca, Cambridge, United Kingdom (N.C., J.W.T., E.G., S.H., D.F.M.); Clinical Pharmacology and Safety Sciences, BioPharmaceuticals R&D, AstraZeneca, Cambridge, United Kingdom (R.V.A.); DMPK, Pharmaron, Beijing, China (D.L., H.D., W.L.); Discovery Sciences, Biopharmaceuticals R&D, AstraZeneca, Cambridge, United Kingdom (D.J.O., G.G.S.); and DMPK Asia, Oncology R & D, AstraZeneca, Shanghai, China (K.C., Y.Y.)
| | - Yumei Yan
- DMPK, Oncology R & D, AstraZeneca, Cambridge, United Kingdom (N.C., J.W.T., E.G., S.H., D.F.M.); Clinical Pharmacology and Safety Sciences, BioPharmaceuticals R&D, AstraZeneca, Cambridge, United Kingdom (R.V.A.); DMPK, Pharmaron, Beijing, China (D.L., H.D., W.L.); Discovery Sciences, Biopharmaceuticals R&D, AstraZeneca, Cambridge, United Kingdom (D.J.O., G.G.S.); and DMPK Asia, Oncology R & D, AstraZeneca, Shanghai, China (K.C., Y.Y.)
| | - Dermot F McGinnity
- DMPK, Oncology R & D, AstraZeneca, Cambridge, United Kingdom (N.C., J.W.T., E.G., S.H., D.F.M.); Clinical Pharmacology and Safety Sciences, BioPharmaceuticals R&D, AstraZeneca, Cambridge, United Kingdom (R.V.A.); DMPK, Pharmaron, Beijing, China (D.L., H.D., W.L.); Discovery Sciences, Biopharmaceuticals R&D, AstraZeneca, Cambridge, United Kingdom (D.J.O., G.G.S.); and DMPK Asia, Oncology R & D, AstraZeneca, Shanghai, China (K.C., Y.Y.)
| |
Collapse
|
4
|
Keylor MH, Gulati A, Kattar SD, Johnson RE, Chau RW, Margrey KA, Ardolino MJ, Zarate C, Poremba KE, Simov V, Morriello GJ, Acton JJ, Pio B, Yan X, Palte RL, McMinn SE, Nogle L, Lesburg CA, Adpressa D, Lin S, Neelamkavil S, Liu P, Su J, Hegde LG, Woodhouse JD, Faltus R, Xiong T, Ciaccio PJ, Piesvaux J, Otte KM, Wood HB, Kennedy ME, Bennett DJ, DiMauro EF, Fell MJ, Fuller PH. Structure-Guided Discovery of Aminoquinazolines as Brain-Penetrant and Selective LRRK2 Inhibitors. J Med Chem 2021; 65:838-856. [PMID: 34967623 DOI: 10.1021/acs.jmedchem.1c01968] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The leucine-rich repeat kinase 2 (LRRK2) protein has been genetically and functionally linked to Parkinson's disease (PD), a disabling and progressive neurodegenerative disorder whose current therapies are limited in scope and efficacy. In this report, we describe a rigorous hit-to-lead optimization campaign supported by structural enablement, which culminated in the discovery of brain-penetrant, candidate-quality molecules as represented by compounds 22 and 24. These compounds exhibit remarkable selectivity against the kinome and offer good oral bioavailability and low projected human doses. Furthermore, they showcase the implementation of stereochemical design elements that serve to enable a potency- and selectivity-enhancing increase in polarity and hydrogen bond donor (HBD) count while maintaining a central nervous system-friendly profile typified by low levels of transporter-mediated efflux and encouraging brain penetration in preclinical models.
Collapse
Affiliation(s)
- Mitchell H Keylor
- Merck & Co., Inc., 33 Avenue Louis Pasteur, Boston, Massachusetts 02115, United States
| | - Anmol Gulati
- Merck & Co., Inc., 33 Avenue Louis Pasteur, Boston, Massachusetts 02115, United States
| | - Solomon D Kattar
- Merck & Co., Inc., 33 Avenue Louis Pasteur, Boston, Massachusetts 02115, United States
| | - Rebecca E Johnson
- Merck & Co., Inc., 33 Avenue Louis Pasteur, Boston, Massachusetts 02115, United States
| | - Ryan W Chau
- Merck & Co., Inc., 33 Avenue Louis Pasteur, Boston, Massachusetts 02115, United States
| | - Kaila A Margrey
- Merck & Co., Inc., 33 Avenue Louis Pasteur, Boston, Massachusetts 02115, United States
| | - Michael J Ardolino
- Merck & Co., Inc., 33 Avenue Louis Pasteur, Boston, Massachusetts 02115, United States
| | - Cayetana Zarate
- Merck & Co., Inc., 33 Avenue Louis Pasteur, Boston, Massachusetts 02115, United States
| | - Kelsey E Poremba
- Merck & Co., Inc., 33 Avenue Louis Pasteur, Boston, Massachusetts 02115, United States
| | - Vladimir Simov
- Merck & Co., Inc., 33 Avenue Louis Pasteur, Boston, Massachusetts 02115, United States
| | - Gregori J Morriello
- Merck & Co., Inc., 2015 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - John J Acton
- Merck & Co., Inc., 2015 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Barbara Pio
- Merck & Co., Inc., 2015 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Xin Yan
- Merck & Co., Inc., 33 Avenue Louis Pasteur, Boston, Massachusetts 02115, United States
| | - Rachel L Palte
- Merck & Co., Inc., 33 Avenue Louis Pasteur, Boston, Massachusetts 02115, United States
| | - Spencer E McMinn
- Merck & Co., Inc., 33 Avenue Louis Pasteur, Boston, Massachusetts 02115, United States
| | - Lisa Nogle
- Merck & Co., Inc., 33 Avenue Louis Pasteur, Boston, Massachusetts 02115, United States
| | - Charles A Lesburg
- Merck & Co., Inc., 33 Avenue Louis Pasteur, Boston, Massachusetts 02115, United States
| | - Donovon Adpressa
- Merck & Co., Inc., 33 Avenue Louis Pasteur, Boston, Massachusetts 02115, United States
| | - Shishi Lin
- Merck & Co., Inc., 2015 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Santhosh Neelamkavil
- Merck & Co., Inc., 2015 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Ping Liu
- Merck & Co., Inc., 33 Avenue Louis Pasteur, Boston, Massachusetts 02115, United States
| | - Jing Su
- Merck & Co., Inc., 2015 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Laxminarayan G Hegde
- Merck & Co., Inc., 33 Avenue Louis Pasteur, Boston, Massachusetts 02115, United States
| | - Janice D Woodhouse
- Merck & Co., Inc., 33 Avenue Louis Pasteur, Boston, Massachusetts 02115, United States
| | - Robert Faltus
- Merck & Co., Inc., 33 Avenue Louis Pasteur, Boston, Massachusetts 02115, United States
| | - Tina Xiong
- Merck & Co., Inc., 33 Avenue Louis Pasteur, Boston, Massachusetts 02115, United States
| | - Paul J Ciaccio
- Merck & Co., Inc., 33 Avenue Louis Pasteur, Boston, Massachusetts 02115, United States
| | - Jennifer Piesvaux
- Merck & Co., Inc., 33 Avenue Louis Pasteur, Boston, Massachusetts 02115, United States
| | - Karin M Otte
- Merck & Co., Inc., 33 Avenue Louis Pasteur, Boston, Massachusetts 02115, United States
| | - Harold B Wood
- Merck & Co., Inc., 2015 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Matthew E Kennedy
- Merck & Co., Inc., 33 Avenue Louis Pasteur, Boston, Massachusetts 02115, United States
| | | | - Erin F DiMauro
- Merck & Co., Inc., 33 Avenue Louis Pasteur, Boston, Massachusetts 02115, United States
| | - Matthew J Fell
- Merck & Co., Inc., 33 Avenue Louis Pasteur, Boston, Massachusetts 02115, United States
| | - Peter H Fuller
- Merck & Co., Inc., 33 Avenue Louis Pasteur, Boston, Massachusetts 02115, United States
| |
Collapse
|
5
|
Ozgür B, Saaby L, Janfelt C, Langthaler K, Eneberg E, Jacobsen AM, Badolo L, Montanari D, Brodin B. Screening novel CNS drug candidates for P-glycoprotein interactions using the cell line iP-gp: In vitro efflux ratios from iP-gp and MDCK-MDR1 monolayers compared to brain distribution data from mice. Eur J Pharm Biopharm 2021; 169:211-219. [PMID: 34756975 DOI: 10.1016/j.ejpb.2021.10.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Revised: 09/17/2021] [Accepted: 10/14/2021] [Indexed: 01/16/2023]
Abstract
Drug efflux by P-glycoprotein (P-gp, ABCB1) is considered as a major obstacle for brain drug delivery for small molecules. P-gp-expressing cell monolayers are used for screening of new drug candidates during early states of drug development. It is, however, uncertain how well the in vitro studies can predict the in vivo P-gp mediated efflux at the blood-brain barrier (BBB). We previously developed a novel cell line of porcine origin, the iP-gp cell line, with high transepithelial resistance and functional expression of human P-gp. The aim of the present study was to evaluate the applicability of the cell line for screening of P-gp interactions of novel drug candidates. For this purpose, bidirectional fluxes of 14 drug candidates were measured in iP-gp cells and in MDCK-MDR1 cells, and compared with pharmacokinetic data obtained in male C57BL/6 mice. The iP-gp cells formed extremely tight monolayers (>15 000 Ω∙cm2) as compared to the MDCK- MDR1 cells (>250 Ω∙cm2) and displayed lower Papp,a-b values. The efflux ratios obtained with iP-gp and MDCK-MDR1 monolayers correlated with Kp,uu,brain values from the in vivo studies, where compounds with the lowest Kp,uu,brain generally displayed the highest efflux ratios. 12 of the tested compounds displayed a poor BBB penetration in mice as judged by Kp,uu less than 1. Of these compounds, nine compounds were categorized as P-gp substrates in the iP-gp screening, whereas analysis of data estimated in MDCK-MDR1 cells indicated four compounds as potential substrates. The results suggest that the iP-gp cell model may be a sensitive and useful screening tool for drug screening purposes to identify possible substrates of human P-glycoprotein.
Collapse
Affiliation(s)
- Burak Ozgür
- Department of Pharmacy, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | - Lasse Saaby
- Department of Pharmacy, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark; Bioneer-FARMA, Department of Pharmacy, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | - Christian Janfelt
- Department of Pharmacy, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | | | - Elin Eneberg
- H. Lundbeck A/S, Ottiliavej 9, 2500 Valby, Denmark
| | | | | | | | - Birger Brodin
- Department of Pharmacy, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark.
| |
Collapse
|
6
|
A Bidirectional Permeability Assay for beyond Rule of 5 Compounds. Pharmaceutics 2021; 13:pharmaceutics13081146. [PMID: 34452112 PMCID: PMC8400635 DOI: 10.3390/pharmaceutics13081146] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Revised: 07/16/2021] [Accepted: 07/18/2021] [Indexed: 12/02/2022] Open
Abstract
Bidirectional permeability measurement with cellular models grown on Transwell inserts is widely used in pharmaceutical research since it not only provides information about the passive permeability of a drug, but also about transport proteins involved in the active transport of drug substances across physiological barriers. With the increasing number of investigative drugs coming from chemical space beyond Lipinski’s Rule of 5, it becomes more and more challenging to provide meaningful data with the standard permeability assay. This is exemplified here by the difficulties we encountered with the cyclic depsipeptides emodepside and its close analogs with molecular weight beyond 1000 daltons and cLogP beyond 5. The aim of this study is to identify potential reasons for these challenges and modify the permeability assays accordingly. With the modified assay, intrinsic permeability and in vitro efflux of depsipeptides could be measured reliably. The improved correlation to in vivo bioavailability and tissue distribution data indicated the usefulness of the modified permeability assay for the in vitro screening of compounds beyond the Rule of 5.
Collapse
|
7
|
Hinca SB, Salcedo C, Wagner A, Goldeman C, Sadat E, Aibar MMD, Maechler P, Brodin B, Aldana BI, Helms HCC. Brain endothelial cells metabolize glutamate via glutamate dehydrogenase to replenish TCA-intermediates and produce ATP under hypoglycemic conditions. J Neurochem 2020; 157:1861-1875. [PMID: 33025588 DOI: 10.1111/jnc.15207] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Revised: 09/29/2020] [Accepted: 10/01/2020] [Indexed: 12/15/2022]
Abstract
The endothelial cells of the blood-brain barrier participate in the regulation of glutamate concentrations in the brain interstitial fluid by taking up brain glutamate. However, endothelial glutamate metabolism has not been characterized, nor is its role in brain glutamate homeostasis and endothelial energy production known. The aim of this study was to investigate endothelial glutamate dehydrogenase (GDH) expression and glutamate metabolism and probe its functional significance. The primary brain endothelial cells were isolated from bovine and mouse brains, and human brain endothelial cells were derived from induced pluripotent stem cells. GDH expression on the protein level and GDH function were investigated in the model systems using western blotting, confocal microscopy, 13 C-glutamate metabolism, and Seahorse assay. In this study, it was shown that GDH was expressed in murine and bovine brain capillaries and in cultured primary mouse and bovine brain endothelial cells as well as in human-induced pluripotent stem cell-derived endothelial cells. The endothelial GDH expression was confirmed in brain capillaries from mice carrying a central nervous system-specific GDH knockout. Endothelial cells from all tested species metabolized 13 C-glutamate to α-ketoglutarate, which subsequently entered the tricarboxylic acid (TCA)-cycle. Brain endothelial cells maintained mitochondrial oxygen consumption rates, when supplied with glutamate alone, whereas glutamate supplied in addition to glucose did not lead to additional oxygen consumption. In conclusion, brain endothelial cells directly take up and metabolize glutamate and utilize the resulting α-ketoglutarate in the tricarboxylic acid cycle to ultimately yield ATP if glucose is unavailable.
Collapse
Affiliation(s)
- Sven B Hinca
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Claudia Salcedo
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Antonie Wagner
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Charlotte Goldeman
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Edris Sadat
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Marco M D Aibar
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Pierre Maechler
- Department of Cell Physiology and Metabolism, CMU, University of Geneva, Geneva, Switzerland
| | - Birger Brodin
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Blanca I Aldana
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Hans C C Helms
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| |
Collapse
|
8
|
Muscle to Brain Partitioning as Measure of Transporter-Mediated Efflux at the Rat Blood-Brain Barrier and Its Implementation into Compound Optimization in Drug Discovery. Pharmaceutics 2019; 11:pharmaceutics11110595. [PMID: 31718023 PMCID: PMC6920949 DOI: 10.3390/pharmaceutics11110595] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Revised: 10/31/2019] [Accepted: 11/08/2019] [Indexed: 12/27/2022] Open
Abstract
Movement of xenobiotic substances across the blood–brain barrier (BBB) is tightly regulated by various transporter proteins, especially the efflux transporters P-glycoprotein (P-gp/MDR1) and breast cancer resistance protein (BCRP). Avoiding drug efflux at the BBB is a unique challenge for the development of new central nervous system (CNS) drugs. Drug efflux at the BBB is described by the partition coefficient of unbound drug between brain and plasma (Kp,uu,brain) which is typically obtained from in vivo and often additionally in vitro measurements. Here, we describe a new method for the rapid estimation of the in vivo drug efflux at the BBB of rats: the measurement of the partition coefficient of a drug between brain and skeletal muscle (Kp,brain/muscle). Assuming a closely similar distribution of drugs into the brain and muscle and that the efflux transporters are only expressed in the brain, Kp,brain/muscle, similar to Kp,uu,brain, reflects the efflux at the BBB. The new method requires a single in vivo experiment. For 64 compounds from different research programs, we show the comparability to other approaches used to obtain Kp,uu,brain. P-gp- and BCRP-overexpressing cell systems are valuable in vitro tools for prescreening. Drug efflux at the BBB can be most accurately predicted based on a simple algorithm incorporating data from both in vitro assays. In conclusion, the combined use of our new in vivo method and the in vitro tools allows an efficient screening method in drug discovery with respect to efflux at the BBB.
Collapse
|
9
|
Development of Human in vitro Brain-blood Barrier Model from Induced Pluripotent Stem Cell-derived Endothelial Cells to Predict the in vivo Permeability of Drugs. Neurosci Bull 2019; 35:996-1010. [PMID: 31079318 DOI: 10.1007/s12264-019-00384-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Accepted: 02/02/2019] [Indexed: 10/26/2022] Open
Abstract
An in vitro blood-brain barrier (BBB) model is critical for enabling rapid screening of the BBB permeability of the drugs targeting on the central nervous system. Though many models have been developed, their reproducibility and renewability remain a challenge. Furthermore, drug transport data from many of the models do not correlate well with the data for in vivo BBB drug transport. Induced-pluripotent stem cell (iPSC) technology provides reproducible cell resources for in vitro BBB modeling. Here, we generated a human in vitro BBB model by differentiating the human iPSC (hiPSC) line GM25256 into brain endothelial-type cells. The model displayed BBB characteristics including tight junction proteins (ZO-1, claudin-5, and occludin) and endothelial markers (von Willebrand factor and Ulex), as well as high trans-endothelial electrical resistance (TEER) (1560 Ω.cm2 ± 230 Ω.cm2) and γ-GTPase activity. Co-culture with primary rat astrocytes significantly increased the TEER of the model (2970 Ω.cm2 to 4185 Ω.cm2). RNAseq analysis confirmed the expression of key BBB-related genes in the hiPSC-derived endothelial cells in comparison with primary human brain microvascular endothelial cells, including P-glycoprotein (Pgp) and breast cancer resistant protein (BCRP). Drug transport assays for nine CNS compounds showed that the permeability of non-Pgp/BCRP and Pgp/BCRP substrates across the model was strongly correlated with rodent in situ brain perfusion data for these compounds (R2 = 0.982 and R2 = 0.9973, respectively), demonstrating the functionality of the drug transporters in the model. Thus, this model may be used to rapidly screen CNS compounds, to predict the in vivo BBB permeability of these compounds and to study the biology of the BBB.
Collapse
|
10
|
Feng S, Zheng L, Tang S, Gu J, Jiang X, Wang L. In-vitro and in situ assessment of the efflux of five antidepressants by breast cancer resistance protein. J Pharm Pharmacol 2019; 71:1133-1141. [PMID: 31037729 DOI: 10.1111/jphp.13100] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2018] [Accepted: 04/07/2019] [Indexed: 01/08/2023]
Abstract
Abstract
Objectives
Antidepressants need to penetrate the blood–brain barrier (BBB) to exert their functions in the central nervous system. Breast cancer resistance protein (BCRP), an efflux transporter abundantly expressed in the BBB, prevents the accumulation of many drugs in the brain. This study aimed to identify whether five commonly used antidepressants (sertraline, duloxetine, fluoxetine, amitriptyline and mirtazapine) are BCRP substrates.
Methods
A combination of bidirectional transport and intracellular accumulation experiments was conducted on BCRP-overexpressing MDCKII and wild-type (WT) cells, and in situ brain perfusion was conducted in rats.
Key findings
The bidirectional transport study revealed that the net efflux ratio (NER) of sertraline reached 2.08 but decreased to 1.06 when co-incubated with Ko143, a selective BCRP inhibitor. Conversely, the other four antidepressants did not appear to be BCRP substrates, due to their low NER values (<1.5). The accumulation of sertraline in MDCKII-BCRP cells was significantly lower than that in MDCKII-WT cells. The presence of Ko143 significantly increased the sertraline accumulation in MDCKII-BCRP cells but not in MDCKII-WT cells. Brain perfusion showed that the permeability of 1 and 5 μm sertraline was significantly higher in the presence of Ko143.
Conclusions
Taken together, BCRP is involved in sertraline efflux.
Collapse
Affiliation(s)
- Suqin Feng
- Department of Clinical Pharmacy and Pharmacy Administration, West China School of Pharmacy, Sichuan University, Chengdu, China
| | - Liang Zheng
- Department of Clinical Pharmacy and Pharmacy Administration, West China School of Pharmacy, Sichuan University, Chengdu, China
| | - Shiwei Tang
- Department of Pharmacy, People's Hospital of Dujiangyan City, Dujiangyan, China
| | - Juan Gu
- Department of Pharmacy, Affiliated Hospital of Zunyi Medical College, Zunyi, China
| | - Xuehua Jiang
- Department of Clinical Pharmacy and Pharmacy Administration, West China School of Pharmacy, Sichuan University, Chengdu, China
| | - Ling Wang
- Department of Clinical Pharmacy and Pharmacy Administration, West China School of Pharmacy, Sichuan University, Chengdu, China
| |
Collapse
|
11
|
Minimal contribution of P-gp on the low brain distribution of naldemedine, a peripherally acting μ-opioid receptor antagonist. Drug Metab Pharmacokinet 2019; 34:126-133. [DOI: 10.1016/j.dmpk.2018.12.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Revised: 12/14/2018] [Accepted: 12/14/2018] [Indexed: 11/22/2022]
|
12
|
Safar Z, Kis E, Erdo F, Zolnerciks JK, Krajcsi P. ABCG2/BCRP: variants, transporter interaction profile of substrates and inhibitors. Expert Opin Drug Metab Toxicol 2019; 15:313-328. [PMID: 30856014 DOI: 10.1080/17425255.2019.1591373] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
INTRODUCTION ABCG2 has a broad substrate specificity and is one of the most important efflux proteins modulating pharmacokinetics of drugs, nutrients and toxicokinetics of toxicants. ABCG2 is an important player in transporter-mediated drug-drug interactions (tDDI). Areas covered: The aims of the review are i) to cover transporter interaction profile of substrates and inhibitors that can be utilized to test interaction of drug candidates with ABCG2, ii) to highlight main characteristics of in vitro testing and iii) to describe the structural basis of the broad substrate specificity of the protein. Preclinical data utilizing Abcg2/Bcrp1 knockouts and clinical studies showing effect of ABCG2 c.421C>A polymorphism on pharmacokinetics of drugs have provided evidence for a broad array of drug substrates and support drug - ABCG2 interaction testing. A consensus on using rosuvastatin and sulfasalazine as intestinal substrates for clinical studies is in the formation. Other substrates relevant to the therapeutic area can be considered. Monolayer efflux assays and vesicular transport assays have been extensively utilized in vitro. Expert opinion: Clinical substrates display complex pharmacokinetics due to broad interaction profiles with multiple transporters and metabolic enzymes. Substrate-dependent inhibition has been observed for several inhibitors. Harmonization of in vitro and in vivo testing makes sense. However, rosuvastatin and sulfasalazine are not efficiently transported in either MDCKII or LLC-PK1-based monolayers. Caco-2 monolayer assays and vesicular transport assays are potential alternatives.
Collapse
Affiliation(s)
| | - Emese Kis
- a SOLVO Biotechnology , Szeged , Hungary
| | - Franciska Erdo
- b Faculty of Information Technology and Bionics , Pázmány Péter Catholic University , Budapest , Hungary
| | | | - Peter Krajcsi
- a SOLVO Biotechnology , Szeged , Hungary.,d Department of Morphology and Physiology. Faculty of Health Sciences , Semmelweis University , Budapest , Hungary
| |
Collapse
|
13
|
Liu H, Dong K, Zhang W, Summerfield SG, Terstappen GC. Prediction of brain:blood unbound concentration ratios in CNS drug discovery employing in silico and in vitro model systems. Drug Discov Today 2018; 23:1357-1372. [PMID: 29548981 DOI: 10.1016/j.drudis.2018.03.002] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Revised: 02/03/2018] [Accepted: 03/08/2018] [Indexed: 12/15/2022]
Abstract
Recent years have seen a paradigm shift away from optimizing the brain:blood concentration ratio toward the more relevant brain:blood unbound concentration ratio (Kp,uu,br) in CNS drug discovery. Here, we review the recent developments in the in silico and in vitro model systems to predict the Kp,uu,br of discovery compounds with special emphasis on the in-vitro-in-vivo correlation. We also discuss clinical 'translation' of rodent Kp,uu,br and highlight the future directions for improvement in brain penetration prediction. Important in this regard are in silico Kp,uu,br models built on larger datasets of high quality, calibration and deeper understanding of experimental in vitro transporter systems, and better understanding of blood-brain barrier transporters and their in vivo relevance aside from P-gp and BCRP.
Collapse
Affiliation(s)
- Houfu Liu
- Platform Technology and Science, GlaxoSmithKline R&D Center, Shanghai, China.
| | - Kelly Dong
- Platform Technology and Science, GlaxoSmithKline R&D Center, Shanghai, China
| | - Wandong Zhang
- Platform Technology and Science, GlaxoSmithKline R&D Center, Shanghai, China
| | - Scott G Summerfield
- Bioanalysis, Immunogenicity and Biomarker, Platform Technology and Science, GlaxoSmithKline, Ware, UK
| | - Georg C Terstappen
- Platform Technology and Science, GlaxoSmithKline R&D Center, Shanghai, China
| |
Collapse
|
14
|
Liu H, Chen Y, Huang L, Sun X, Fu T, Wu S, Zhu X, Zhen W, Liu J, Lu G, Cai W, Yang T, Zhang W, Yu X, Wan Z, Wang J, Summerfield SG, Dong K, Terstappen GC. Drug Distribution into Peripheral Nerve. J Pharmacol Exp Ther 2018; 365:336-345. [DOI: 10.1124/jpet.117.245613] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Accepted: 03/01/2018] [Indexed: 12/20/2022] Open
|
15
|
Lu H, Yang T, Xu Z, Lin X, Ding Q, Zhang Y, Cai X, Dong K, Gong S, Zhang W, Patel M, Copley RCB, Xiang J, Guan X, Wren P, Ren F. Discovery of Novel 1-Cyclopentenyl-3-phenylureas as Selective, Brain Penetrant, and Orally Bioavailable CXCR2 Antagonists. J Med Chem 2018; 61:2518-2532. [DOI: 10.1021/acs.jmedchem.7b01854] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Hongfu Lu
- Neurosciences Therapeutic Area Unit, GSK Pharmaceuticals R&D, 898 Halei Road, Zhangjiang Hi-Tech Park, Pudong, Shanghai 201203, P. R. China
| | - Ting Yang
- Neurosciences Therapeutic Area Unit, GSK Pharmaceuticals R&D, 898 Halei Road, Zhangjiang Hi-Tech Park, Pudong, Shanghai 201203, P. R. China
| | - Zhongmiao Xu
- Neurosciences Therapeutic Area Unit, GSK Pharmaceuticals R&D, 898 Halei Road, Zhangjiang Hi-Tech Park, Pudong, Shanghai 201203, P. R. China
| | - Xichen Lin
- Neurosciences Therapeutic Area Unit, GSK Pharmaceuticals R&D, 898 Halei Road, Zhangjiang Hi-Tech Park, Pudong, Shanghai 201203, P. R. China
| | - Qian Ding
- Neurosciences Therapeutic Area Unit, GSK Pharmaceuticals R&D, 898 Halei Road, Zhangjiang Hi-Tech Park, Pudong, Shanghai 201203, P. R. China
| | - Yueting Zhang
- R&D Projects Clinical Platforms and Sciences, GSK Pharmaceuticals R&D, 898 Halei Road, Zhangjiang Hi-Tech Park, Pudong, Shanghai 201203, P. R. China
| | - Xin Cai
- Platform Technology Sciences, GSK Pharmaceuticals R&D, 898 Halei Road, Zhangjiang Hi-Tech Park, Pudong, Shanghai 201203, P. R. China
| | - Kelly Dong
- Platform Technology Sciences, GSK Pharmaceuticals R&D, 898 Halei Road, Zhangjiang Hi-Tech Park, Pudong, Shanghai 201203, P. R. China
| | - Sophie Gong
- Platform Technology Sciences, GSK Pharmaceuticals R&D, 898 Halei Road, Zhangjiang Hi-Tech Park, Pudong, Shanghai 201203, P. R. China
| | - Wei Zhang
- Platform Technology Sciences, GSK Pharmaceuticals R&D, 898 Halei Road, Zhangjiang Hi-Tech Park, Pudong, Shanghai 201203, P. R. China
| | - Metul Patel
- Platform Technology Sciences, GSK Pharmaceuticals R&D, Stevenage, Hertfordshire SG1 2NY, U.K
| | - Royston C. B. Copley
- Platform Technology & Science, GSK Medicines Research Centre, Gunnels Wood Road, Stevenage, Hertfordshire SG1 2NY, U.K
| | - Jianing Xiang
- Neurosciences Therapeutic Area Unit, GSK Pharmaceuticals R&D, 898 Halei Road, Zhangjiang Hi-Tech Park, Pudong, Shanghai 201203, P. R. China
| | - Xiaoming Guan
- Neurosciences Therapeutic Area Unit, GSK Pharmaceuticals R&D, 898 Halei Road, Zhangjiang Hi-Tech Park, Pudong, Shanghai 201203, P. R. China
| | - Paul Wren
- Neurosciences Therapeutic Area Unit, GSK Pharmaceuticals R&D, 1250 South Collegeville Road, Collegeville, Pennsylvania 19426, United States
| | - Feng Ren
- Neurosciences Therapeutic Area Unit, GSK Pharmaceuticals R&D, 898 Halei Road, Zhangjiang Hi-Tech Park, Pudong, Shanghai 201203, P. R. China
| |
Collapse
|
16
|
Braun C, Sakamoto A, Fuchs H, Ishiguro N, Suzuki S, Cui Y, Klinder K, Watanabe M, Terasaki T, Sauer A. Quantification of Transporter and Receptor Proteins in Dog Brain Capillaries and Choroid Plexus: Relevance for the Distribution in Brain and CSF of Selected BCRP and P-gp Substrates. Mol Pharm 2017; 14:3436-3447. [PMID: 28880093 DOI: 10.1021/acs.molpharmaceut.7b00449] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Transporters at the blood-brain barrier (BBB) and the blood-cerebrospinal fluid barrier (BCSFB) play a pivotal role as gatekeepers for efflux or uptake of endogenous and exogenous molecules. The protein expression of a number of them has already been determined in the brains of rodents, nonhuman primates, and humans using quantitative targeted absolute proteomics (QTAP). The dog is an important animal model for drug discovery and development, especially for safety evaluations. The purpose of the present study was to clarify the relevance of the transporter protein expression for drug distribution in the dog brain and CSF. We used QTAP to examine the protein expression of 17 selected transporters and receptors at the dog BBB and BCSFB. For the first time, we directly linked the expression of two efflux transporters, P-glycoprotein (P-gp) and breast cancer resistance protein (BCRP), to regional brain and CSF distribution using specific substrates. Two cocktails, each containing one P-gp substrate (quinidine or apafant) and one BCRP substrate (dantrolene or daidzein) were infused intravenously prior to collection of the brain. Transporter expression varied only slightly between the capillaries of different brain regions and did not result in region-specific distribution of the investigated substrates. There were, however, distinct differences between brain capillaries and choroid plexus. Largest differences were observed for BCRP and P-gp: both were highly expressed in brain capillaries, but no BCRP and only low amounts of P-gp were detected in the choroid plexus. Kp,uu,brain and Kp,uu,CSF of both P-gp substrates were indicative of drug efflux. Also, Kp,uu,brain for the BCRP substrates was low. In contrast, Kp,uu,CSF for both BCRP substrates was close to unity, resulting in Kp,uu,CSF/Kp,uu,brain ratios of 7 and 8, respectively. We conclude that the drug transporter expression profiles differ between the BBB and BCSFB in dogs, that there are species differences in the expression profiles, and that CSF is not a suitable surrogate for unbound brain concentrations of BCRP substrates in dogs.
Collapse
Affiliation(s)
- Clemens Braun
- Drug Discovery Sciences, Boehringer Ingelheim Pharma GmbH & Co. KG , 88397 Biberach an der Riss, Germany
| | - Atsushi Sakamoto
- Kobe Pharma Research Institute, Nippon Boehringer Ingelheim Co., Ltd. , Kobe 650-0046, Japan
| | - Holger Fuchs
- Drug Discovery Sciences, Boehringer Ingelheim Pharma GmbH & Co. KG , 88397 Biberach an der Riss, Germany
| | - Naoki Ishiguro
- Kobe Pharma Research Institute, Nippon Boehringer Ingelheim Co., Ltd. , Kobe 650-0046, Japan
| | - Shinobu Suzuki
- Kobe Pharma Research Institute, Nippon Boehringer Ingelheim Co., Ltd. , Kobe 650-0046, Japan
| | - Yunhai Cui
- Drug Discovery Sciences, Boehringer Ingelheim Pharma GmbH & Co. KG , 88397 Biberach an der Riss, Germany
| | - Klaus Klinder
- Drug Discovery Sciences, Boehringer Ingelheim Pharma GmbH & Co. KG , 88397 Biberach an der Riss, Germany
| | - Michitoshi Watanabe
- Proteomedix Frontiers Co., Ltd , T-Biz, 6-6-40 Aoba, Aramaki, Aoba-ku, Sendai 980-8579, Japan.,Division of Membrane Transport and Drug Targeting, Graduate School of Pharmaceutical Sciences, Tohoku University , 6-3 Aoba, Aramaki, Aoba-ku, Sendai 980-8578, Japan
| | - Tetsuya Terasaki
- Division of Membrane Transport and Drug Targeting, Graduate School of Pharmaceutical Sciences, Tohoku University , 6-3 Aoba, Aramaki, Aoba-ku, Sendai 980-8578, Japan
| | - Achim Sauer
- Drug Discovery Sciences, Boehringer Ingelheim Pharma GmbH & Co. KG , 88397 Biberach an der Riss, Germany
| |
Collapse
|