IL-17在皮质发育障碍难治性癫痫血脑屏障破坏中的作用及其机制

A number of publications have indicated that IL-17 promotes Blood-brain barrier disruption (BBBD) through an IL-17/IL-17 receptor (IL-17R) combination in CNS disorders. BBBD play an important role in the development of refractory epilepsy with malformation of cortical development（MCD). Our previous studies showed the protein levels of IL-17 and IL-17R in refractory epilepsy with MCD positively correlated with the frequency of seizures, and IL-17 and IL-17R were highly expressed in vascular endothelial cells. Thus, we suppose that IL-17 may contribute to the recurrence or exacerbation of seizure activity in refractory epilepsy with MCD through BBBD. However，the specific mechanisms of BBBD of refractory epilepsy with MCD via IL-17 were not determined. In this study, through comprehensive utilization of technologies such as morphology, molecular biology, electrophysiology in surgical specimens of refractory epilepsy with MCD and animal models of refractory epilepsy with MCD, we investigate the role of IL-17 in the BBBD of refractory epilepsy with MCD, and IL-17 induced BBBD of refractory epilepsy with MCD through down-regulation of the tight junction molecule which will be realised with increased MLCK and/or MLCP activity and phosphorylation of myosin light chain (MLC) and/or induced activation of the endothelial machinery. Clarifying above issues will be valuably to elucidate the role of IL-17 in the pathological mechanism of refractory epilepsy with MCD, which will provide experiment evidence for the treatment of refractory epilepsy.

在中枢神经系统疾病中IL-17与其受体（IL-17R）结合可诱导血脑屏障破坏（BBBD）。而BBBD在皮质发育障碍（MCD）所致难治性癫痫的发展中具有重要的作用。我们研究表明：IL-17与其受体在MCD难治性癫痫中的表达水平与癫痫的发作频率呈正相关，并在血管内皮细胞中高表达。据此，我们推测：IL-17有可能通过BBBD来导致或加剧MCD难治性癫痫。但其具体机制尚不清楚。本项目拟用MCD难治性癫痫临床标本、动物模型为研究对象，综合运用形态学、分子生物学和神经电生理等技术研究：①IL-17在MCD难治性癫痫BBB破坏中的作用；②IL-17可能通过调节MLCK和/或MLCP的活性而提高MLC的磷酸化水平，进而下调紧密连接分子（occludin和ZO-1）和激活内皮收缩机制而导致BBB破坏。阐明上述问题，将有助于认识IL-17在MCD难治性癫痫病理机制中的作用，为控制难治性癫痫发作提供实验依据。

在中枢神经系统疾病中IL-17与其受体（IL-17R）结合可诱导血脑屏障破坏（BBBD）。而BBBD在皮质发育障碍（MCD）所致难治性癫痫的发展中具有重要的作用。前期研究表明：IL-17与其受体在MCD难治性癫痫中的表达水平与癫痫的发作频率呈正相关，并在血管内皮细胞中高表达，可能引起了难治性癫痫的发生。我们研究发现：1）从mRNA 和蛋白水平证实IL-17/IL-17R 在MTLE难治性癫痫海马和皮层中表达较正常对照组明显上调，免疫组化和免疫荧光双标发现IL-17/IL-17R高表达于MTLE和MCD中神经元，星形胶质细胞，小胶质细胞，少突胶质前体细胞，血管内皮细胞。2）从蛋白水平研究发现IL-17可上调神经元和胶质细胞TRPV1的表达；同时发现F-MCD小鼠模型的微脑回皮质发育障碍（MCD）组织中TRPV1的表达较sham组明显上调，免疫组化和免疫荧光双标结果表明TRPV1高表达于神经元和星形胶质细胞；进一步采用青霉素诱导小鼠F-MCD癫痫发作模型，结合视频脑电及行为学研究，发现TRPV1-/-组癫痫发作持续的总时间以及放电频率均显著低于WT组，以上结果表明IL-17可通过TRPV1发挥致痫作用。3）从mRNA和蛋白水平证实Rev-Erbα在 MTLE难治性癫痫海马和皮层中表达较正常对照组明显下调，免疫组化和免疫荧光双标发现Rev-Erbα表达于神经元，星形胶质细胞，小胶质细胞；进一步采用普鲁卡因诱导MTLE小鼠模型发现Rev-Erbα在海马和皮层中表达类似临床标本；并且采用SR009（Rev-Erbα激动剂）治疗7天后可减少炎症因子的产生和神经元的凋亡和丢失。以上结果表明Rev-Erbα可通过减少炎症因子的产生和神经元的丢失和凋亡发挥抗癫痫作用。