孕烷受体X及其下游目的基因编码蛋白在小鼠慢性颞叶癫痫模型的表达  

The expression of Pregnane X receptor and the products of itsdownstream targeted genes in chronic temporal lobe epilepsy mice

作　　者：孙琬冰 王剑虹 洪震 SUN Wanbing;WANG Jianhong;HONG Zhen(Department of Neurology,Huashan Affiliated Hospital of Fudan University,Shanghai (200040),China)

机构地区：[1]复旦大学附属华山医院神经内科,上海200040

出　　处：《癫痫与神经电生理学杂志》2018年第6期321-326,共6页Journal of Epileptology and Electroneurophysiology(China)

基　　金：国家自然科学基金青年项目(NO:81501120,81271443);上海市卫生计生委科研课题(NO:20154Y0135,2017BR003);上海市青年科技启明星计划(NO:16QA1400900).

摘　　要：目的:探究孕烷受体X(pregnane X receptor,PXR)及其下游目的基因编码蛋白P-糖蛋白(P-glycoprotein,P-gp)和细胞色素P450 3A4(cytochrome P450 3A4,CYP3A4)在小鼠慢性颞叶癫痫模型中的表达情况及对脑内卡马西平浓度的影响。方法:雄性C57/BL小鼠(n=30)随机分为模型组(n=20)和对照组(n=10)。模型组使用海人酸(kainic acid,KA)海马原位注射构建海人酸点燃模型,对照组同一位置注射等体积生理盐水。通过行为学及脑电图监测筛选慢性颞叶癫痫模型。Western blot检测PXR、P-gp及CYP3A4在海马内的表达水平。使用免疫荧光技术对P-gp和CYP3A4进行双标,检测其共表达;卡马西平连续给药7d后,通过高效液相色谱法(HPLC)检测脑组织内卡马西平浓度。结果:模型组小鼠中55%出现反复自发性发作行为及脑电图上典型的痫样放电,确认为慢性颞叶癫痫模型。模型组小鼠海马PXR表达水平较对照组显著增高(P<0.0001)。P-gp(P<0.001)和CYP3A4(P<0.001)的表达水平也较对照组显著增高,而且在模型组小鼠脑组织内存在显著共表达。模型组小鼠脑内卡马西平浓度显著低于对照组(P<0.05)。结论:PXR表达上调后可能通过同时激活下游目的基因编码蛋白P-gp和CYP3A4使二者发挥协同作用从而介导癫痫耐药。Objective:To explore the expression of pregnane X receptor (PXR)and the products of its downstream targeted genes in chronic temporal epilepsy mice and the effect on the carbamazepine (CBZ)concentration of brain.Methods:Male C57/BL mice (n=30)were randomly divided into the model group (n=20)and the control group (n=10).Kainic acid (KA)kindled mice were produced by intraeerebral administration of KA.Saline was administrated at the same site instead of KA in the control group.Mice with chronic temporal lobe epilepsy were screened by behavioral manifestations monitoring and EEG recording.The expression of PXR,P-glycoprotein (P-gp)and cytochrome P450 3A4(CYP3A4)were detected by western blot.Immunofluorescence was used to detect the co-expression of P-gp and CYP3A4.The concentration of CBZ was measured by HPLC after continuous administration for 7days.Results:Recurrent spontaneous seizures and epiIeptiform discharge of 55% mice in the model group were detected and confirmed as symptoms of chronic temporal lobe epilepsy.The expression of PXR in hippocampus of mice in the model group increased significantly compared with controls (P<0.0001).The expression of P-gp and CYP3A4 also increased and the co-expression occurred in the brain tissues of the model group.The CBZ concentration of mice in the model group was significantly lower than that of controls (P<0.05).Conclusions:The upregulation of PXR may simultaneously activate the coexpression of both P-gp and CYP3A4 and induce epileptic drug resistance synergistically.

关 键 词：耐药性癫痫 颞叶癫痫 孕烷受体X(PXR) P-糖蛋白(P-gp) 细胞色素P4503A4(CYP3A4) 

分 类 号：R9533[医药卫生—药学] R742.1