Inhibition of P-Glycoprotein by HIV Protease Inhibitors Increases Intracellular Accumulation of Berberine in Murine and Human Macrophages

Authors

Weibin Zha, Virginia Commonwealth University, China Pharmaceutical University
Guangji Wang, China Pharmaceutical University
Weiren Xu, Tianjin Institute of Pharmaceutical Research
Xuyuan Liu, Tianjin Institute of Pharmaceutical Research
Yun Wang, Virginia Commonwealth University
Beth S. Zha, Virginia Commonwealth University
Jian Shi, China Pharmaceutical University
Qijin Zhao, China Pharmaceutical University
Phillip M. Gerk, Virginia Commonwealth University
Elaine Studer, Virginia Commonwealth University
Phillip B. Hylemon, Virginia Commonwealth University
William M. Pandak Jr., McGuire Veterans Affairs Medical Center
Huiping Zhou, Virginia Commonwealth University, Wenzhou Medical College

Document Type

Article

Original Publication Date

2013

Journal/Book/Conference Title

PLOS ONE

Volume

8

DOI

10.1371/journal.pone.0054349

Comments

Originally Published at http://dx.doi.org/10.1371/journal.pone.0054349

Date of Submission

November 2014

Abstract

Background

HIV protease inhibitor (PI)-induced inflammatory response in macrophages is a major risk factor for cardiovascular diseases. We have previously reported that berberine (BBR), a traditional herbal medicine, prevents HIV PI-induced inflammatory response through inhibiting endoplasmic reticulum (ER) stress in macrophages. We also found that HIV PIs significantly increased the intracellular concentrations of BBR in macrophages. However, the underlying mechanisms of HIV PI-induced BBR accumulation are unknown. This study examined the role of P-glycoprotein (P-gp) in HIV PI-mediated accumulation of BBR in macrophages.

Methodology and Principal Findings

Cultured mouse RAW264.7 macrophages, human THP-1-derived macrophages, Wild type MDCK (MDCK/WT) and human P-gp transfected (MDCK/P-gp) cells were used in this study. The intracellular concentration of BBR was determined by HPLC. The activity of P-gp was assessed by measuring digoxin and rhodamine 123 (Rh123) efflux. The interaction between P-gp and BBR or HIV PIs was predicated by Glide docking using Schrodinger program. The results indicate that P-gp contributed to the efflux of BBR in macrophages. HIV PIs significantly increased BBR concentrations in macrophages; however, BBR did not alter cellular HIV PI concentrations. Although HIV PIs did not affect P-gp expression, P-gp transport activities were significantly inhibited in HIV PI-treated macrophages. Furthermore, the molecular docking study suggests that both HIV PIs and BBR fit the binding pocket of P-gp, and HIV PIs may compete with BBR to bind P-gp.

Conclusion and Significance

HIV PIs increase the concentration of BBR by modulating the transport activity of P-gp in macrophages. Understanding the cellular mechanisms of potential drug-drug interactions is critical prior to applying successful combinational therapy in the clinic.

Rights

This is an open-access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.

Is Part Of

VCU Microbiology and Immunology Publications