P2 receptor antagonists prevent synaptic failure and extracellular signal-regulated kinase1/2 activation induced by oxygen and glucose deprivation in rat CA1 hippocampus in vitro

The function and regulation of Na+/H+ exchanger isoform 1 (NHE1) following cerebral ischemia are not well understood. In this study, we demonstrate that extracellular signal-related kinases (ERK1/2) play a role in stimulation of neuronal NHE1 following in vitro ischemia. NHE1 activity was significantly increased during 10-60 min reoxygenation (REOX) after 2-h oxygen and glucose deprivation (OGD). OGD/REOX not only increased the Vmax for NHE1 but also shifted the Km toward decreased [H+]i. These changes in NHE1 kinetics were absent when MAPK/ERK kinase (MEK) was inhibited by the MEK inhibitor U0126. There were no changes in the levels of phosphorylated ERK1/2 (p-ERK1/2) after 2 h OGD. The p-ERK1/2 level was significantly increased during 10-60 min REOX, which was accompanied by nuclear translocation. U0126 abolished REOX-induced elevation and translocation of p-ERK1/2. We further examined the ERK/90-kDa ribosomal S6 kinase (p90RSK) signaling pathways. At 10 min REOX, phosphorylated NHE1 was increased with a concurrent elevation of phosphorylation of p90RSK, a known NHE1 kinase. Inhibition of MEK activity with U0126 abolished phosphorylation of both NHE1 and p90RSK. Moreover, neuroprotection was observed with U0126 or genetic ablation or pharmacological inhibition of NHE1 following OGD/REOX. Taken together, these results suggest that activation of ERK1/2-p90RSK pathways following in vitro ischemia phosphorylates NHE1 and increases its activity, which subsequently contributes to neuronal damage.

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Curcumin protects cortical neurons against oxygen and glucose deprivation/reoxygenation injury through flotillin-1 and extracellular signal-regulated kinase1/2 pathway

Biochemical and Biophysical Research Communications ◽

10.1016/j.bbrc.2018.01.089 ◽

2018 ◽

Vol 496 (2) ◽

pp. 515-522 ◽

Cited By ~ 3

Author(s):

Zhengyu Lu ◽

Yanping Liu ◽

Yang Shi ◽

Xinjie Shi ◽

Xin Wang ◽

...

Keyword(s):

Cortical Neurons ◽

Glucose Deprivation ◽

Oxygen And Glucose Deprivation ◽

Extracellular Signal ◽

Reoxygenation Injury

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Molecular and Pharmacological Modulation of CALHM1 Promote Neuroprotection against Oxygen and Glucose Deprivation in a Model of Hippocampal Slices

Cells ◽

10.3390/cells9030664 ◽

2020 ◽

Vol 9 (3) ◽

pp. 664 ◽

Cited By ~ 4

Author(s):

Javier Garrosa ◽

Iñigo Paredes ◽

Philippe Marambaud ◽

Manuela G. López ◽

María F. Cano-Abad

Keyword(s):

Neuroprotective Effect ◽

Hippocampal Slices ◽

Glucose Deprivation ◽

Point Of View ◽

Oxygen And Glucose Deprivation ◽

Molecular Events ◽

Vitro Model ◽

Species Production ◽

Reperfusion Phase

Calcium homeostasis modulator 1 (CALHM1) is a calcium channel involved in the regulation of cytosolic Ca2+ levels. From a physiological point of view, the open state of CALHM1 depends not only on voltage but also on the extracellular concentration of calcium ([Ca2+]) ions. At low [Ca2+]e or depolarization, the channel is opened, allowing Ca2+ influx; however, high extracellular [Ca2+]e or hyperpolarization promote its resting state. The unique Ca2+ permeation of CALHM1 relates to the molecular events that take place in brain ischemia, such as depolarization and extracellular changes in [Ca2+]e, particularly during the reperfusion phase after the ischemic insult. In this study, we attempted to understand its role in an in vitro model of ischemia, namely oxygen and glucose deprivation, followed by reoxygenation (OGD/Reox). To this end, hippocampal slices from wild-type Calhm1+/+, Calhm1+/−, and Calhm1−/− mice were subjected to OGD/Reox. Our results point out to a neuroprotective effect when CALHM1 is partially or totally absent. Pharmacological manipulation of CALHM1 with CGP37157 reduced cell death in Calhm1+/+ slices but not in that of Calhm1−/− mice after exposure to the OGD/Reox protocol. This ionic protection was also verified by measuring reactive oxygen species production upon OGD/Reox in Calhm1+/+ and Calhm1−/− mice, resulting in a downregulation of ROS production in Calhm1−/− hippocampal slices and increased expression of HIF-1α. Taken together, we can conclude that genetic or pharmacological inhibition of CALHM1 results in a neuroprotective effect against ischemia, due to an attenuation of the neuronal calcium overload and downregulation of oxygen reactive species production.

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Hyperhomocysteinemia increases damage on brain slices exposed to in vitro model of oxygen and glucose deprivation: prevention by folic acid

International Journal of Developmental Neuroscience ◽

10.1016/j.ijdevneu.2006.01.002 ◽

2006 ◽

Vol 24 (4) ◽

pp. 285-291 ◽

Cited By ~ 11

Author(s):

Bárbara Tagliari ◽

Lauren L. Zamin ◽

Christianne G. Salbego ◽

Carlos Alexandre Netto ◽

Angela T.S. Wyse

Keyword(s):

Folic Acid ◽

In Vitro Model ◽

Brain Slices ◽

Glucose Deprivation ◽

Oxygen And Glucose Deprivation ◽

Vitro Model

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Potential Therapeutic Applications of P2 Receptor Antagonists: From Bench to Clinical Trials

Current Drug Targets ◽

10.2174/1389450120666190213095923 ◽

2019 ◽

Vol 20 (9) ◽

pp. 919-937 ◽

Cited By ~ 4

Author(s):

Natiele C. da Silva Ferreira ◽

Luiz A. Alves ◽

Rômulo J. Soares-Bezerra

Keyword(s):

Clinical Trials ◽

P2 Receptors ◽

Experimental Models ◽

New Drugs ◽

Receptor Subtype ◽

P2 Receptor ◽

Receptor Antagonists ◽

Purines And Pyrimidines

Background: Extracellular purines and pyrimidines have important physiological functions in mammals. Purines and pyrimidines act on P1 and P2 purinergic receptors, which are widely expressed in the plasma membrane in various cell types. P2 receptors act as important therapeutic targets and are associated with several disorders, such as pain, neurodegeneration, cancer, inflammation, and thrombosis. However, the use of antagonists for P2 receptors in clinical therapy, with the exception of P2Y12, is a great challenge. Currently, many research groups and pharmaceutical companies are working on the development of specific antagonist molecules for each receptor subtype that could be used as new medicines to treat their respective disorders. Objective: The present review compiles some interesting findings on the application of P2 receptor antagonists in different in vitro and in vivo experimental models as well as the progress of advanced clinical trials with these compounds. Conclusion: Despite all of the exciting results obtained on the bench, few antagonists of P2 receptors advanced to the clinical trials, and once they reach this stage, the effectiveness of the therapy is not guaranteed, as in the example of P2X7 antagonists. Despite this, P2Y12 receptor antagonists have a history of success and have been used in therapy for at least two decades to prevent thrombosis in patients at risk for myocardial infarctions. This breakthrough is the motivation for scientists to develop new drugs with antagonistic activity for the other P2 receptors; thus, in a matter of years, we will have an evolution in the field of purinergic therapy.

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