Abstract
Mesial temporal sclerosis (MTS) is the most frequent cause of drug resistant symptomatic
partial epilepsy. The mechanism and genetic background of this unique pathology are
not well understood. Aquaporins (AQP) are regulators of water homeostasis in the brain
and are expressed in the human hippocampus. We explored the role of AQP genes in the
pathogenetic mechanisms of MTS through an evaluation of gene expression in surgically
removed human brain tissue. We analyzed AQP1 and 4 mRNA levels by quantitative real-time polymerase chain reaction and normalized to
ABL and cyclophilin genes, followed by immunohistochemistry for AQP4. Relative expressions were calculated according to the delta Ct method and the results
were compared using the Mann-Whitney U test. Brain specimens of 23 patients with epilepsy
who had undergone surgery for MTS and seven control autopsy specimens were investigated.
Clinical findings were concordant with previous studies and 61% of the patients were
seizure-free in the postoperative period. AQP1 and 4 gene expression levels did not differ between MTS patients and control groups. Immunofluorescence
analysis of AQP4 supported the expression results, showing no difference. Previous studies have reported
contradictory results about the expression levels of AQP in MTS. To our knowledge, only one study has suggested upregulation whereas the other
indicated downregulation of perivascular AQP4. Our study did not support these findings and may rule out the involvement of AQP
in human MTS.
Keywords
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Article info
Publication history
Accepted:
December 2,
2012
Received:
July 2,
2012
Identification
Copyright
© 2013 Elsevier Ltd. Published by Elsevier Inc. All rights reserved.
