Induction of P-glycoprotein expression and activity by ritonavir in bovine brain microvessel endothelial cells

Extended treatment with human immunodeficiency virus (HIV) protease inhibitors (HPIs) is standard in HIV/AIDS therapy. While these drugs have helped decrease the overall incidence of AIDS defining illnesses, the relative prevalence of HIV/AIDS dementia has increased. HPIs may cause induction of bloo...

Full description

Saved in:
Bibliographic Details
Published in:Journal of pharmacy and pharmacology 2007-07, Vol.59 (7), p.947-953
Main Authors: Perloff, Michael D., von Moltke, Lisa L., Fahey, Jeanne M., Greenblatt, David J.
Format: Article
Language:English
Subjects:
Animals
ATP-Binding Cassette, Sub-Family B, Member 1 - biosynthesis
ATP-Binding Cassette, Sub-Family B, Member 1 - metabolism
Blood-Brain Barrier - metabolism
Blotting, Western
Brain - blood supply
Cattle
Cells, Cultured
Endothelium, Vascular - metabolism
HIV Protease Inhibitors - adverse effects
Human immunodeficiency virus
Ritonavir - adverse effects
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Extended treatment with human immunodeficiency virus (HIV) protease inhibitors (HPIs) is standard in HIV/AIDS therapy. While these drugs have helped decrease the overall incidence of AIDS defining illnesses, the relative prevalence of HIV/AIDS dementia has increased. HPIs may cause induction of blood‐brain barrier (BBB) drug transporters (P‐glycoprotein; P‐gp) and thereby limit entry of HPIs into brain tissue, increasing the probability that the brain could become an HIV sanctuary site. Using bovine brain microvessel endothelial cells (BMEC) as an in‐vitro model of the BBB, the potential for the HIV protease inhibitor ritonavir to cause induction of P‐gp activity and expression was examined. BMEC were isolated from fresh cow brain by enzymatic digest and density centrifugation. Primary culture BMEC were co‐incubated with ritonavir or vehicle control for 120 h. Quantitative drug accumulation of rhodamine 123 (Rh123) and fluorescence microscopy were used as measures of P‐gp activity. P‐gp expression was assessed using quantitative Western blotting. Ritonavir decreased Rh123 cell accumulation and increased P‐gp immunoreactive protein in a concentration‐dependent manner. Fluorescent microscopy mirrored Rh123 quantitative studies. In BMEC pretreated with 30 μM ritonavir, Rh123 accumulation was decreased 40% and immunoreactive P‐gp protein increased 2‐fold. Collectively, a strong correlation between decreased Rh123 BMEC accumulation and increased P‐gp immunoreactive protein was observed (Spearman r2 = 0.77, P < 0.0001). Thus extended exposure of BMEC to ritonavir caused a concentration‐dependent increase in P‐gp activity and expression. Similar findings may occur at the clinical level with prolonged HIV protease inhibitor use, giving insight into the central nervous system as an HIV sanctuary site and eventual development of HIV dementia.
ISSN:0022-3573
2042-7158
DOI:10.1211/jpp.59.7.0006