Expression Pattern And Function Of FBXL20 In Epilepsy Patients And Rat Model

Objective:FBXL20, an E3 ubiquitin ligase widely expressed in neurons of the CNS, is very important in metabolism of RIM1( regulating synaptic membrane exocytosis 1), participated in variety of neurodegenerative disease. To investigate the role of FBXL20 in the formation of epilepsy, we detected the expression levels of FBXL20,and its downstream protein RIM1 in brain tissue of patients with epilepsy and SD rat model induced by pilocarpine, also through FBXL20 overexpression lentivirus in rat model.Methods:1.Expression:Epilepsy focus resected from temporal lobe epilepsy patients as the epilepsy group(n=25), cortex resected from brain trauma patients as the control group(n=10);. 40 male, healthy SD rats were injected with pilocarpine(127 mg/kg).Rats induced spontaneous seizures 2 weeks later were selected into epilepsy model group, those did not induce spontaneous seizures until 2 months later were selected into control group. FBXL20, RIM1 in human brain cortex and rat cortex and hippocampus were detected by immunofluorescence staining,western blot and Immunohistochemistry assay. 2.Intervention:(1) Behavior observation of epilepsy animal model after spontaneous epileptic seizures: SD rats injected with pilocarpine were randomly divided into three groups after reaching spontaneous seizure standards, including EP+LV-empty group, EP+LV-FBXL20 group, Sham group. Video monito to record Racine scores and the frequency of epileptic seizures.Results:Immunofluorescence staining showed that FBXL20 mainly located in neurons. Immunohistochemistry assay and Western blot showed that the expression levels of FBXL20 was down-regulated in epilepsy group(P<0.05). Western blot indicated that expression levels of RIM1 was up-regulated in epilepsy group( P < 0.05);after spontaneous seizures induced by pilocarpine, Racine scores and frequence of seizures were reduced in LV-FBXL20 group compared with LV-empty group and sham group(P<0.05), also expression of RIM1 in LV-FBXL20 group were reduced.Conclusion:Altered expression of FBXL20 indicating that FBXL20 might be involved in epileptogenesis through regulating metabolism of RIM1.