Details

Autor(en) / Beteiligte

• McInerney, Mitchell P.
• Volitakis, Irene
• Bush, Ashley I.
• Banks, William A.
• Short, Jennifer L.
• Nicolazzo, Joseph A.

Titel

Ionophore and Biometal Modulation of P-glycoprotein Expression and Function in Human Brain Microvascular Endothelial Cells

Ist Teil von

• Pharmaceutical research, 2018-04, Vol.35 (4), p.83-12, Article 83

Ort / Verlag

New York: Springer US

Erscheinungsjahr

2018

Quelle

SpringerLink

Beschreibungen/Notizen

• Purpose Biometals such as zinc and copper have been shown to affect tight junction expression and subsequently blood-brain barrier (BBB) integrity. Whether these biometals also influence the expression and function of BBB transporters such as P-glycoprotein (P-gp) however is currently unknown. Methods Using the immortalised human cerebral microvascular endothelial (hCMEC/D3) cell line, an in-cell western assay (alongside western blotting) assessed relative P-gp expression after treatment with the metal ionophore clioquinol and biometals zinc and copper. The fluorescent P-gp substrate rhodamine-123 was employed to observe functional modulation, and inductively coupled plasma mass spectrometry (ICP-MS) provided information on biometal trafficking. Results A 24-h treatment with clioquinol, zinc and copper (0.5, 0.5 and 0.1 μM) induced a significant upregulation of P-gp (1.7-fold) assessed by in-cell western and this was confirmed with western blotting (1.8-fold increase). This same treatment resulted in a 23% decrease in rhodamine-123 accumulation over a 1 h incubation. ICP-MS demonstrated that while t8his combination treatment had no effect on intracellular zinc concentrations, the treatment significantly enhanced bioavailable copper (4.6-fold). Conclusions Enhanced delivery of copper to human brain microvascular endothelial cells is associated with enhanced expression and function of the important efflux pump P-gp, which may provide therapeutic opportunities for P-gp modulation.