Uptake characteristics of pinocembrin and its effect on p-glycoprotein at the blood-brain barrier in in vitro cell experiments

J Asian Nat Prod Res. 2012;14(1):14-21. doi: 10.1080/10286020.2011.620393.

Abstract

One purpose of the present study was to investigate the uptake characteristics of pinocembrin (PCB) and its effect on p-glycoprotein (P-gp) at the blood-brain barrier (BBB). Cultured rat brain microvascular endothelial cells (rBMECs) were used as an in vitro BBB model. Experiments were conducted to examine time-, concentration-, and temperature-dependent elements of PCB uptake, and the effect of classical P-gp inhibitors, cyclosporin A (CsA) and verapamil (Ver), on the steady-state uptake of PCB. Uptake of rhodamine 123 (Rho123), the typical P-gp substance, was measured with or without PCB. Meanwhile, the protein level of P-gp after incubation with PCB was detected by Western blot assay. The results demonstrated that PCB uptake by rBMECs was in a time- and concentration-dependent manner. CsA and Ver slightly increased PCB steady-state uptake by less than 10% (p>0.05). Similar results were observed in Rho123 uptake by co-administration of PCB. Further results were obtained by Western blot assay. PCB might not affect P-gp expression in rBMECs. Overall, the findings demonstrate that the passive transport process may be the main process for PCB to pass through the BBB, and P-gp is likely to have a little effect on the PCB transport process. Furthermore, PCB may not affect the functional activity and the protein expression of the P-gp transporter at the BBB.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • ATP Binding Cassette Transporter, Subfamily B, Member 1 / metabolism*
  • Animals
  • Biological Transport
  • Blood-Brain Barrier / drug effects*
  • Brain / drug effects
  • Cyclosporine / pharmacology
  • Dose-Response Relationship, Drug
  • Flavanones / chemistry
  • Flavanones / pharmacology*
  • Neuroprotective Agents / chemistry
  • Neuroprotective Agents / pharmacology*
  • Rats
  • Rhodamine 123 / pharmacology*
  • Verapamil / pharmacology

Substances

  • ATP Binding Cassette Transporter, Subfamily B, Member 1
  • Flavanones
  • Neuroprotective Agents
  • Rhodamine 123
  • Cyclosporine
  • pinocembrin
  • Verapamil