Abstracts

Rationale: Glioblastomas show high incidence of epilepsy. The tyrosine kinase family protein, Lyn plays an important role in synaptic excitability mediated neuroinflammation. Accordingly, Lyn could mediate the mechanism between inflammation excitability in acquired epileptogenesis related to glioblastoma. The goal was to examine levels of Lyn in vivo and in vitro of glioma and in synaptosome extract from experimental temporal lobe epilepsy. Methods: Glioblastoma cells (U87MG) was implanted in the right striatum in adult female nude mice. Behavior was monitoring during 6 weeks. Total Lyn and phosphorylated Lyn were analyzed in glioblastoma cell culture in clinical relevant Lyn kinase inhibitor, was administered at different doses during cell growth. Status epilepticus (SE) was induced by intraperitoneal administration of pilocarpine followed by diazepam administration 90 minutes later in adult male C57BL/6 mice. Seizures were monitored using continuous video-local field potential recordings during 7 days and then brain samples were collected for histology and western blot analysis according established protocols. Mice with spontaneous seizures only were selected for the study. Coronal sections of the brain were stained against anti p-Lyn and co-localized with synaptic markers. Dorsal hippocampal regions were analyzed through decovo-immunofluorescence microscopy and imaging software. Synaptosome was extracted from the total hippocampi and homogenized in sucrose solution, then stored for assay in a buffer with a cocktail of various protease inhibitors. Western Blots were performed in glioblastoma and synaptosome samples with the phosphorylated Lyn antibody and detected using chemiluminescence western detection kit. Immunoblot images were acquired using scanner and analyzed with imaging software. Results: Level of phosphorylated Lyn increased in glioblastoma and also in synaptosome extracts from hippocampi of epileptogenic mice. Lyn activation was effectively inhibited by bafetinib. In addition p-Lyn IR like profiles increase in hippocampal layers and co-localized with synaptic markers. Conclusions: Lyn activation could mediate neuronal hyper-excitability during acquired epileptogenesis. Inhibition of Lyn kinase may provide a new therapeutic target as antiepileptogenesis mediated by gliomas.