Dexmedetomidine protects against oxygen–glucose deprivation-induced injury through the I2 imidazoline receptor-PI3K/AKT pathway in rat C6 glioma cells
Open Access
- 24 November 2011
- journal article
- Published by Oxford University Press (OUP) in Journal of Pharmacy and Pharmacology
- Vol. 64 (1) , 120-127
Abstract
Objectives: To explore the protection and the mechanism of dexmedetomidine on the oxygen–glucose deprivation (OGD) insults in rat C6 glioma cells. Methods: Cells were subjected to OGD then assessed by viability studies. After dexmedetomidine treatment, p-AKT, hypoxia-inducible factor (HIF)-1α, vascular endothelial growth factor (VEGF) and RTP801 expression were measured. Key findings: Three hours of OGD decreased cell viability to 48.8%, which was reversed to 67.4% by 1 µm dexmedetomidine. Hoechst 33342 and propidium iodide double stains showed that the protection of dexmedetomidine was mainly by an anti-apoptosis effect, which was also strengthened by decreasing caspase-3 expression. Dexmedetomidine protection was mainly blocked by the I2 imidazoline receptor antagonist idazoxan and BU 224, but not by the α1-adrenoceptor antagonist prazosin, the α2-adrenoceptor antagonist yohimbine and RX 821002, or the I1 imidazoline receptor antagonist efaroxan. On the other hand, dexmedetomidine enhanced AKT phosphorylation. Furthermore, the protection of dexmedetomidine was blocked by the PI3K/AKT inhibitor wortmannin. The proteins of HIF-1α, VEGF and RTP801 were significantly increased by dexmedetomidine treatment. Conclusions: Dexmedetomidine activated the I2 imidazoline receptor-PI3K/AKT pathway, and up-regulated HIF-1α, VEGF and RTP801 expression to protect against OGD-induced injury in rat C6 cells.Keywords
This publication has 20 references indexed in Scilit:
- MODULATION OF THE PHOSPHOINOSITIDE 3-KINASE SIGNALING PATHWAY ALTERS HOST RESPONSE TO SEPSIS, INFLAMMATION, AND ISCHEMIA/REPERFUSION INJURYShock, 2006
- Histamine protects against NMDA‐induced necrosis in cultured cortical neurons through H2 receptor/cyclic AMP/protein kinase A and H3 receptor/GABA release pathwaysJournal of Neurochemistry, 2006
- Neuroprotection by Alpha 2-Adrenergic Agonists in Cerebral IschemiaCurrent Neuropharmacology, 2005
- α2-Adrenoceptor agonists: shedding light on neuroprotection?British Medical Bulletin, 2005
- Cellular oxygen sensing need in CNS function: physiological and pathological implicationsJournal of Experimental Biology, 2004
- Identification of a Novel Hypoxia-Inducible Factor 1-Responsive Gene, RTP801 , Involved in ApoptosisMolecular and Cellular Biology, 2002
- Effect of the α2-Agonist Dexmedetomidine on Cerebral Neurotransmitter Concentrations during Cerebral Ischemia in RatsAnesthesiology, 2002
- Concurrent Assessment of Calpain and Caspase-3 Activation after Oxygen–Glucose Deprivation in Primary Septo-Hippocampal CulturesJournal of Cerebral Blood Flow & Metabolism, 2001
- HIF-1 and mechanisms of hypoxia sensingCurrent Opinion in Cell Biology, 2001
- Hypoxia, HIF-1, and the Pathophysiologi of Common Human Diseases2000