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Magnetic labeling of pancreatic β-cells modulates the glucose- and insulin-induced phosphorylation of ERK1/2 and AKT.
- Source :
-
Contrast media & molecular imaging [Contrast Media Mol Imaging] 2013 Jan-Feb; Vol. 8 (1), pp. 20-6. - Publication Year :
- 2013
-
Abstract
- This study was undertaken to investigate the effect of a magnetic resonance imaging (MRI) contrast agent, superparamagnetic iron oxide nanoparticle (SPIO), on signal transduction by glucose and insulin in pancreatic β-cells. INS-1 cells were labeled in culture medium containing clinically approved SPIO for 24 h. Labeled and unlabeled cells were stimulated with glucose (25 mM) or insulin (0.1-1 µM) for 12 h. The phosphorylation of extracellular signal-regulated kinase1/2 (ERK1/2) and protein kinase B (AKT) and intracellular insulin protein levels were assessed by Western blotting. After labeling with increasing amounts of SPIO, cytotoxicity was not observed, yet the intracellular iron concentration increased in a dose-dependent manner. SPIO labeling (200 µg Fe ml(-1)) induced a significant increase in ERK1/2 and AKT phosphorylation (labeled vs unlabeled, p < 0.05), but significantly reduced the glucose-stimulated phosphorylation of ERK1/2 and AKT and insulin-stimulated phosphorylation of AKT (labeled vs unlabeled, p < 0.05). The level of intracellular insulin protein was found to be lower in labeled cells than unlabeled cells (labeled vs unlabeled, p < 0.05). This study demonstrates that SPIO labeling alters some fundamental functional variables, at least in INS-1 cells, through modulation of the glucose- or insulin-induced activation of ERK1/2 and AKT, which leads to insulin biosynthesis.<br /> (Copyright © 2012 John Wiley & Sons, Ltd.)
- Subjects :
- Animals
Cell Line, Tumor
Contrast Media pharmacology
Ferric Compounds pharmacology
Insulin-Secreting Cells pathology
Magnetic Resonance Imaging methods
Phosphorylation drug effects
Proto-Oncogene Proteins c-akt
Rats
Contrast Media adverse effects
Ferric Compounds adverse effects
Glucose metabolism
Insulin biosynthesis
Insulin-Secreting Cells metabolism
MAP Kinase Signaling System drug effects
Magnetite Nanoparticles adverse effects
Mitogen-Activated Protein Kinase 3 metabolism
Subjects
Details
- Language :
- English
- ISSN :
- 1555-4317
- Volume :
- 8
- Issue :
- 1
- Database :
- MEDLINE
- Journal :
- Contrast media & molecular imaging
- Publication Type :
- Academic Journal
- Accession number :
- 23109389
- Full Text :
- https://doi.org/10.1002/cmmi.1490