The potential role of human multidrug resistance protein 1 (MDR1) and multidrug resistance-associated protein 2 (MRP2) in the transport of Huperzine A in vitro

Abstract

1. More than 30% of epilepsy patients suffer pharmacoresistance. Transport of antileptic drugs by P-glycoprotein (P-gp) and MRP2 plays an important role in drug-resistant epilepsy. Huperzine A (Hup-A) is a natural compound, which might have potential in treating neurological disorders including epilepsy and Alzheimer’s disease. In this study, we investigated whether human P-gp and MRP2 transport Hup-A.

2. LLC-PK1 and MDCKII cells transfected with human P-gp or MRP2 were used to establish concentration equilibrium transport assays (CETAs) and determine the transport profile of Hup-A. The expression of P-gp and MRP2 was detected by qPCR and western blotting. The transport function of P-gp and MRP2 was measured by Rho123 and CDFDA cell uptake assay.

3. In CETAs, Hup-A at concentrations of 10 ng/mL or 2 µg/mL was transported by MDR1 and MRP2 from basolateral to apical sides of the cell monolayers. P-gp and MRP2 inhibitors completely blocked the efflux of Hup-A. There was no efflux of Hup-A in LLC-PK1 or MDCKII wild-type (WT) cells.

4. We demonstrate that Hup-A is a substrate of P-gp and MRP2. These results imply the efflux of Hup-A across the blood-brain barrier (BBB) in vivo, suggesting potential drug resistance of Hup-A.

Keywords:

• P-glycoprotein
• Hup-A
• drug-resistant epilepsy
• drug transporter
• cell monolayer

Acknowledgments

Cell lines were kindly provided by Prof. P. Borst, The Netherlands Cancer Institute.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

Financial support was provided by National Natural Science Foundation of China under Grants [NSFC-31771400, NSFC-81728006, NSFC-81501129, NSFC-81860662]; Natural Science Foundation of Jiangxi Province under Grants [20161BAB215200, 20171ACB21001, 20171BCB23029]; Science and Technology Project of Jiangxi Provincial Education Department under Grant [150111]; and Science and Technology Project of Health and Family Planning Commission of Jiangxi Provence under Grant [20175534].