scholarly journals Mild Hypothermia Reduces Zinc Translocation, Neuronal Cell Death, and Mortality after Transient Global Ischemia in Mice

2002 ◽  
Vol 22 (10) ◽  
pp. 1231-1238 ◽  
Author(s):  
Daisuke Tsuchiya ◽  
Shwuhuey Hong ◽  
Sang Won Suh ◽  
Takamasa Kayama ◽  
S. Scott Panter ◽  
...  
Keyword(s):  
Cell Death ◽  
Hippocampal Neurons ◽  
Mild Hypothermia ◽  
Neuronal Cell Death ◽  
Neuronal Cell ◽  
Global Ischemia ◽  
Doppler Flowmetry ◽  
Transient Global Ischemia ◽  
Hematoxylin Eosin ◽  
Cortical Perfusion

The authors sought to determine whether Zn2+ translocation associated with neuronal cell death occurs after transient global ischemia (TGI) in mice, as has been previously shown in rats, and to determine the effect of mild hypothermia on this reaction. To validate the TGI model, carbon-black injection and laser-Doppler flowmetry were compared in three strains of mice (C57BL/6, SV129, and HSP70 transgenic mice) to assess posterior communicating artery (PcomA) development and cortical perfusion. In C57BL/6 mice, optimal results were obtained when subjected to 20-minute TGI. Brain and rectal temperature measurements were compared to monitor hypothermia. Results of TGI were compared in normothermia (NT; 37°C) and mild hypothermia groups (HT; 33°C) by staining with Zn2+-specific fluorescent dye, N-(6-methoxy-8-quinolyl)-para-toluenesulfonamide (TSQ) and hematoxylin– eosin 72 hours after reperfusion. The Zn2+ translocation observed in hippocampus CA1, CA2, and Hilus 72 hours after 20 minutes of TGI was significantly reduced by mild hypothermia. The number of degenerating neurons in the HT group was significantly less than in the NT group. Mild hypothermia reduced mortality significantly (7.1% in HT, 42.9% in NT). Results suggest that mild hypothermia may reduce presynaptic Zn2+ release in mice, which protects vulnerable hippocampal neurons from ischemic necrosis. Future studies may further elucidate mechanisms of Zn2+-induced ischemic injury.

scholarly journals TNFα-induced AMPA-receptor trafficking in CNS neurons; relevance to excitotoxicity?

2004 ◽  
Vol 1 (3) ◽  
pp. 263-273 ◽  
Author(s):  
DMITRI LEONOUDAKIS ◽  
STEVEN P. BRAITHWAITE ◽  
MICHAEL S. BEATTIE ◽  
ERIC C. BEATTIE
Keyword(s):  
Cell Death ◽  
Inflammatory Response ◽  
Hippocampal Neurons ◽  
Neuronal Damage ◽  
Neuronal Cell Death ◽  
Neuronal Cell ◽  
Cell Types ◽  
Synaptic Function ◽  
Ampar Trafficking ◽  
Novel Target

Injury and disease in the CNS increases the amount of tumor necrosis factor α (TNFα) that neurons are exposed to. This cytokine is central to the inflammatory response that occurs after injury and during prolonged CNS disease, and contributes to the process of neuronal cell death. Previous studies have addressed how long-term apoptotic-signaling pathways that are initiated by TNFα might influence these processes, but the effects of inflammation on neurons and synaptic function in the timescale of minutes after exposure are largely unexplored. Our published studies examining the effect of TNFα on trafficking of AMPA-type glutamate receptors (AMPARs) in hippocampal neurons demonstrate that glial-derived TNFα causes a rapid (<15 minute) increase in the number of neuronal, surface-localized, synaptic AMPARs leading to an increase in synaptic strength. This indicates that TNFα-signal transduction acts to facilitate increased surface localization of AMPARs from internal postsynaptic stores. Importantly, an excess of surface localized AMPARs might predispose the neuron to glutamate-mediated excitotoxicity and excessive intracellular calcium concentrations, leading to cell death. This suggests a new mechanism for excitotoxic TNFα-induced neuronal death that is initiated minutes after neurons are exposed to the products of the inflammatory response.Here we review the importance of AMPAR trafficking in normal neuronal function and how abnormalities that are mediated by glial-derived cytokines such as TNFα can be central in causing neuronal disorders. We have further investigated the effects of TNFα on different neuronal cell types and present new data from cortical and hippocampal neurons in culture. Finally, we have expanded our investigation of the temporal profile of the action of this cytokine relevant to neuronal damage. We conclude that TNFα-mediated effects on AMPAR trafficking are common in diverse neuronal cell types and very rapid in their onset. The abnormal AMPAR trafficking elicited by TNFα might present a novel target to aid the development of new neuroprotective drugs.

scholarly journals Ghrelin attenuates kainic acid-induced neuronal cell death in the mouse hippocampus

2010 ◽  
Vol 205 (3) ◽  
pp. 263-270 ◽  
Author(s):  
Jiyeon Lee ◽  
Eunjin Lim ◽  
Yumi Kim ◽  
Endan Li ◽  
Seungjoon Park
Keyword(s):  
Cell Death ◽  
Kainic Acid ◽  
Hippocampal Neurons ◽  
Therapeutic Potential ◽  
Excitatory Amino Acid ◽  
Neuroprotective Effect ◽  
Neuronal Cell Death ◽  
Neuronal Cell ◽  
Proinflammatory Mediators ◽  
Hippocampal Neurodegeneration

Ghrelin is an endogenous ligand for GH secretagogue receptor type 1a (GHSR1a), and is produced and released mainly from the stomach. It has been recently demonstrated that ghrelin can function as a neuroprotective factor by inhibiting apoptotic pathways. Kainic acid (KA), an excitatory amino acid l-glutamate analog, causes neuronal death in the hippocampus; previous studies suggest that activated microglia and astrocytes actively participate in the pathogenesis of KA-induced hippocampal neurodegeneration. However, it is unclear whether ghrelin has neuroprotective effect in KA-induced hippocampal neurodegeneration. I.p. injection of KA produced typical neuronal cell death in the CA1 and CA3 pyramidal layers of the hippocampus, and the systemic administration of ghrelin significantly attenuated KA-induced neuronal cell death in these regions through the activation of GHSR1a. Ghrelin prevents KA-induced activation of microglia and astrocytes, and the expression of proinflammatory mediators tumor necrosis factor α, interleukin-1β, and cyclooxygenase-2. The inhibitory effect of ghrelin on the activation of microglia and astrocytes appears to be associated with the inhibition of matrix metalloproteinase-3 expression in damaged hippocampal neurons. Our data suggest that ghrelin has a therapeutic potential for suppressing KA-induced pathogenesis in the brain.

scholarly journals Caspase-3-Like Protease Activity-Independent Apoptosis at the Onset of Neuronal Cell Death in the Gerbil Hippocampus after Global Ischemia

2007 ◽  
Vol 30 (10) ◽  
pp. 1950-1953 ◽  
Author(s):  
Hiroki Shimizu ◽  
Makoto Ohgoh ◽  
Masuhiro Ikeda ◽  
Yukio Nishizawa ◽  
Hiroo Ogura
Keyword(s):  
Cell Death ◽  
Protease Activity ◽  
Caspase 3 ◽  
Neuronal Cell Death ◽  
Neuronal Cell ◽  
Global Ischemia

Intraischemic mild hypothermia prevents neuronal cell death and tissue loss after neonatal cerebral hypoxia-ischemia

2006 ◽  
Vol 23 (2) ◽  
pp. 387-393 ◽  
Author(s):  
Changlian Zhu ◽  
Xiaoyang Wang ◽  
Falin Xu ◽  
Lin Qiu ◽  
Xiuyong Cheng ◽  
...  
Keyword(s):  
Cell Death ◽  
Mild Hypothermia ◽  
Neuronal Cell Death ◽  
Neuronal Cell ◽  
Tissue Loss ◽  
Cerebral Hypoxia ◽  
Hypoxia Ischemia

scholarly journals Xenon Neurotoxicity in Rat Hippocampal Slice Cultures Is Similar to Isoflurane and Sevoflurane

2013 ◽  
Vol 119 (2) ◽  
pp. 335-344 ◽  
Author(s):  
Heather Brosnan ◽  
Philip E. Bickler
Keyword(s):  
Cell Death ◽  
Hippocampal Neurons ◽  
Neuronal Cell Death ◽  
Neuronal Cell ◽  
Neuron Death ◽  
Neuroprotective Effects ◽  
Low Concentrations ◽  
Vitro Model ◽  
Developing Neurons

Abstract Background: Anesthetic neurotoxicity in the developing brain of rodents and primates has raised concern. Xenon may be a nonneurotoxic alternative to halogenated anesthetics, but its toxicity has only been studied at low concentrations, where neuroprotective effects predominate in animal models. An equipotent comparison of xenon and halogenated anesthetics with respect to neurotoxicity in developing neurons has not been made. Methods: Organotypic hippocampal cultures from 7-day-old rats were exposed to 0.75, 1, and 2 minimum alveolar concentrations (MAC) partial pressures (60% xenon at 1.2, 2.67, and 3.67 atm; isoflurane at 1.4, 1.9, and 3.8%; and sevoflurane at 3.4 and 6.8%) for 6 h, at atmospheric pressure or in a pressure chamber. Cell death was assessed 24 h later with fluorojade and fluorescent dye exclusion techniques. Results: Xenon caused death of hippocampal neurons in CA1, CA3, and dentate regions after 1 and 2 MAC exposures, but not at 0.75 MAC. At 1 MAC, xenon increased cell death 40% above baseline (P &lt; 0.01; ANOVA with Dunnett test). Both isoflurane and sevoflurane increased neuron death at 1 but not 2 MAC. At 1 MAC, the increase in cell death compared with controls was 63% with isoflurane and 90% with sevoflurane (both P &lt; 0.001). Pretreatment of cultures with isoflurane (0.75 MAC) reduced neuron death after 1 MAC xenon, isoflurane, and sevoflurane. Conclusion: Xenon causes neuronal cell death in an in vitro model of the developing rodent brain at 1 MAC, as does isoflurane and sevoflurane at similarly potent concentrations. Preconditioning with a subtoxic dose of isoflurane eliminates this toxicity.

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