NCX1 is a new rest target gene: role in cerebral ischemia.

Abstract

The Na(+)-Ca(2+) exchanger 1 (NCX1), a bidirectional transporter that mediates the electrogenic exchange of one calcium ion for three sodium ions across the plasma membrane, is known to be involved in brain ischemia. Since the RE1-silencing transcription factor (REST) is a key modulator of neuronal gene expression in several neurological conditions, we studied the possible involvement of REST in regulating NCX1 gene expression and activity in stroke. We found that: (1) REST binds in a sequence specific manner and represses through H4 deacetylation, ncx1 gene in neuronal cells by recruting CoREST, but not mSin3A. (2) In neurons and in SH-SY5Y cells REST silencing by siRNA and site-direct mutagenesis of REST consensus sequence on NCX1 brain promoter determined an increase in NCX1 promoter activity. (3) By contrast, REST overexpression caused a reduction in NCX1 protein expression and activity. (4) Interestingly, in rats subjected to transient middle cerebral artery occlusion (tMCAO) and in organotypic hippocampal slices or SH-SY5Y cells exposed to oxygen and glucose deprivation (OGD) plus reoxygenation (RX), the increase in REST was associated with a decrease in NCX1. However, this reduction was reverted by REST silencing. (5) REST knocking down, along with the deriving NCX1 overexpression in the deep V and VIb cortical layers caused a marked reduction in infarct volume after tMCAO. Double silencing of REST and NCX1 completely abolished neuroprotection induced by siREST administration. Collectively, these results demonstrate that REST, by regulating NCX1 expression, may represent a potential druggable target for the treatment of brain ischemia.

• Authors: Luigi Formisano, Natascia Guida, Valeria Valsecchi, Giuseppe Pignataro, Antonio Vinciguerra, Anna Pannaccione, Agnese Secondo, Francesca Boscia, Pasquale Molinaro, Maria Jose Sisalli, Rossana Sirabella, Antonella Casamassa, Lorella M T Canzoniero, Gianfranco Di Renzo, Lucio Annunziato
• Journal: Neurobiology of disease (Neurobiol Dis) Vol. 50 Pg. 76-85 (Feb 2013) ISSN: 1095-953X [Electronic] United States
• PMID: 23069678 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2012 Elsevier Inc. All rights reserved.

Chemical References

• RE1-silencing transcription factor
• Repressor Proteins
• Sodium-Calcium Exchanger
• sodium-calcium exchanger 1

Topics

• Animals
• Base Sequence
• Blotting, Western
• Brain Ischemia (genetics, metabolism)
• Chromatin Immunoprecipitation
• Electrophoretic Mobility Shift Assay
• Fluorescent Antibody Technique
• Gene Expression Regulation (genetics)
• Hippocampus (metabolism)
• Humans
• Microscopy, Confocal
• Molecular Sequence Data
• Mutagenesis, Site-Directed
• Neurons (metabolism)
• Organ Culture Techniques
• Rats
• Rats, Sprague-Dawley
• Rats, Wistar
• Real-Time Polymerase Chain Reaction
• Repressor Proteins (genetics, metabolism)
• Sodium-Calcium Exchanger (genetics, metabolism)
• Transfection