Increasing Intracellular Levels of Iron with Ferric Ammonium Citrate Leads to Reduced P-glycoprotein Expression in Human Immortalised Brain Microvascular Endothelial Cells
Autor: | Yijun Pan, Stephanie A. Newman, Joseph A. Nicolazzo, Jennifer L. Short |
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Rok vydání: | 2021 |
Předmět: |
ATP Binding Cassette Transporter
Subfamily B Iron Pharmaceutical Science 02 engineering and technology Blood–brain barrier Ferric Compounds 030226 pharmacology & pharmacy Cell Line 03 medical and health sciences chemistry.chemical_compound 0302 clinical medicine Downregulation and upregulation Alzheimer Disease medicine Humans Pharmacology (medical) P-glycoprotein Pharmacology chemistry.chemical_classification Reactive oxygen species Amyloid beta-Peptides biology Organic Chemistry Endothelial Cells 021001 nanoscience & nanotechnology Molecular biology Quaternary Ammonium Compounds Blot Neuroprotective Agents medicine.anatomical_structure chemistry Blood-Brain Barrier Microvessels biology.protein Molecular Medicine Ferric Endothelium Vascular Reactive Oxygen Species 0210 nano-technology Deferiprone Intracellular Biotechnology medicine.drug |
Zdroj: | Pharmaceutical Research. 38:97-111 |
ISSN: | 1573-904X 0724-8741 |
Popis: | P-glycoprotein (P-gp) at the blood-brain barrier (BBB) precludes the brain penetration of many xenobiotics and mediates brain-to-blood clearance of β-amyloid, which accumulates in the Alzheimer’s disease (AD) brain. Zinc and copper are reported to modulate BBB expression and function of P-gp; however, the impact of exogenous iron, which accumulates in AD, on P-gp dynamics remains unknown. P-gp protein and MDR1 transcript levels were assessed in immortalised human cerebral microvascular endothelial (hCMEC/D3) cells treated with ferric ammonium citrate (FAC; 250 μM, 72 h), by Western blotting and RT-qPCR, respectively. P-gp function was assessed using rhodamine-123 and [3H]-digoxin accumulation. Intracellular reactive oxygen species (ROS) levels were determined using 2′,7′-dichlorofluorescin diacetate and intracellular iron levels quantified using a ferrozine assay. FAC treatment significantly reduced P-gp protein (36%) and MDR1 mRNA (16%) levels, with no significant change in rhodamine-123 or [3H]-digoxin accumulation. While P-gp/MDR1 downregulation was associated with elevated ROS and intracellular iron, MDR1 downregulation was not attenuated with the antioxidant N-acetylcysteine nor the iron chelators desferrioxamine and deferiprone, suggesting the involvement of a ROS-independent mechanism or incomplete iron chelation. These studies demonstrate that iron negatively regulates P-gp expression at the BBB, potentially impacting CNS drug delivery and brain β-amyloid clearance. |
Databáze: | OpenAIRE |
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