title: Effects of brain IKKβ gene silencing by small interfering RNA on P-glycoprotein expression and brain damage in the rat kainic acid-induced seizure model.
abstract: Multidrug resistance mediated by over-expression of P-glycoprotein (P-gp) in brain is an important mechanism accounting for the drug-therapy failure in epilepsy. Over-expression of P-gp in epilepsy rat brain may be regulated by inflammation and nuclear factor-kappa B (NF-κB) activation. Inhibitory κ B kinase subunit β (IKKβ) is an up-stream molecular controlling NF-κB activation. With the small interfering RNA (siRNA) technique and kainic acid (KA)-induced rat epileptic seizure model, the present study was aimed to further evaluate the role of NF-κB inhibition, via blocking IKKβ gene transcription, in the epileptic brain P-gp over-expression, seizure susceptibility, and post-seizure brain damage. siRNA targeting IKKβ was administered to rats via intracerebroventricular injection before seizure induction by KA microinjection; scrambled siRNA was used as control. Brain mRNA and protein levels of IKKβ and P-gp were detected by RT-PCR and immunohistochemistry. NF-κB activity was measured by electrophoretic mobility shift assay. Latency to grade III or V seizure onset was recorded, brain damage was evaluated by neuronal cell counting and epileptiform activity was monitored by electroencephalography. IKKβ siRNA pre-treatment inhibited NF-κB activation and abolished P-gp over-expression in KA-induced epileptic rat brain, accompanied by decreased seizure susceptibility. These findings suggested that epileptogenic-induced P-gp over-expression could be regulated by IKKβ through the NF-κB pathway.
authors.forename: Nian
authors.initials: N
authors.lastname: Yu
authors.forename: Hao
authors.initials: H
authors.lastname: Liu
authors.forename: Yan-Fang
authors.initials: YF
authors.lastname: Zhang
authors.forename: Ling-Ying
authors.initials: LY
authors.lastname: Su
authors.forename: Xin-Hong
authors.initials: XH
authors.lastname: Liu
authors.forename: Le-Chao
authors.initials: LC
authors.lastname: Li
authors.forename: Jin-Bo
authors.initials: JB
authors.lastname: Hao
authors.forename: Xian-Jing
authors.initials: XJ
authors.lastname: Huang
authors.affiliation: Department of Neurology, Nanjing Brain Hospital, Nanjing Medical University, 264 Guangzhou Road, Nanjing, Jiangsu, 210009, China. diqing@medmail.com.cn.
authors.forename: Qing
authors.initials: Q
authors.lastname: Di
mesh_terms: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000378:metabolism*; D000818:Animals; D001921:Brain / Q000378:metabolism* / Q000473:pathology; D004195:Disease Models, Animal; D015870:Gene Expression; D051550:I-kappa B Kinase / Q000235:genetics* / Q000378:metabolism*; D007608:Kainic Acid; D008297:Male; D016328:NF-kappa B / Q000378:metabolism; D009474:Neurons / Q000473:pathology / Q000502:physiology; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000378:metabolism*; D017207:Rats, Sprague-Dawley; D012640:Seizures / Q000378:metabolism* / Q000473:pathology; D014158:Transcription, Genetic
chemical_list: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D016328:NF-kappa B; D034741:RNA, Small Interfering; D051550:I-kappa B Kinase; D007608:Kainic Acid