Decreased ERp57 Expression in WAG/Rij Rats Thalamus and Cortex: Possible Correlation with Absence Epilepsy

Background: The role of intracellular proteins in the pathogenesis of absence epilepsy were mentioned. These proteins are thought to be related to energy generation, signal transduction, inflammation processes and membrane conductance. Objectives: The investigation of protein profile of the genetically epileptic rat brains was the main subject of this study. Methods: For this, a 2D-gel electrophoresis based comparative proteome analysis was performed using thalamus tissue of genetic absence epileptic WAG/Rij and age matched Wistar rats. Regulated spots displaying differences in their abundance were identified using MALDI-TOF/TOF. Among the six spots (DHRS9, BR44, HINT1, CREM, SPRE and PDIA3/ERp57) the highest mascot score was attributed to ERp57 a neuroprotective/neurodegenerative system associated protein. Western Blot analyses were performed to validate changes occurring at ERp57 in thalamus and also identify changes in fronto-parietal cortex. Results: Reductions in the expression levels of ERp57 were detected in the thalamic and the fronto-parietal brain regions of the WAG/Rij rats in comparison to Wistar rats. Conclusion: Such difference might be associated with the pathogenic mechanisms dictating the absence epilepsy. Lower levels of ERp57 may be playing an important role in the development of spontaneous seizures activity seen in the absence epileptic WAG/Rij rats strain.