Department of Physiology, Hubei Provincial Key Laboratory of Developmentally Originated Disorder, School of Basic Medical Sciences, Wuhan University, Wuhan 430071, China.
Department of Pathology, Zhongnan Hospital, Wuhan University, Wuhan 430071, China.
Brain Behav Immun. 2015 Aug;48:68-77. doi: 10.1016/j.bbi.2015.01.017. Epub 2015 Mar 20.
Febrile seizure (FS) is the most common seizure disorder in children, and children with FS are regarded as a high risk for the eventual development of epilepsy. Brain inflammation may be implicated in the mechanism of FS. Transient receptor potential vanilloid 1 (TRPV1) is believed to act as a monitor and regulator of body temperature. The role of inflammation in synaptic plasticity mediation indicates that TRPV1 is relevant to several nervous system diseases, such as epilepsy. Here, we report a critical role for TRPV1 in a febrile seizure mouse model and reveal increased levels of pro-inflammatory factors in the immature brain. Animals were subjected to hyperthermia for 30 min, which generates seizures lasting approximately 20 min, and then were used for experiments. To invoke frequently repetitive febrile seizures, mice are exposed to hyperthermia for three times daily at an interval of 4h between every time induced seizure, and a total of 4 days to induce. Behavioral testing for febrile seizures revealed that a TRPV1 knock-out mouse model demonstrated a prolonged onset latency and a shortened duration and seizure grade of febrile seizure when compared with wild type (WT) mice. The expression levels of both TRPV1 mRNA and protein increased after a hyperthermia-induced febrile seizure in WT mice. Notably, TRPV1 activation resulted in a significant elevation in the expression of pro-inflammatory cytokines (IL-1β, IL-6, TNF-α and HMGB1) in the hippocampus and cortex. These data indicate that the reduction of TRPV1 expression parallels a decreased susceptibility to febrile seizures. Thus, preventative strategies might be developed for use during febrile seizures.
热性惊厥(FS)是儿童中最常见的癫痫发作疾病,患有 FS 的儿童被认为是最终发展为癫痫的高风险人群。脑炎症可能与 FS 的发病机制有关。瞬时受体电位香草醛 1(TRPV1)被认为是体温的监测和调节者。炎症在突触可塑性调节中的作用表明 TRPV1与几种神经系统疾病有关,如癫痫。在这里,我们报告 TRPV1 在发热性惊厥小鼠模型中的关键作用,并揭示不成熟大脑中促炎因子水平升高。动物接受 30 分钟的高热处理,产生持续约 20 分钟的惊厥,然后进行实验。为了诱发频繁的复发性热性惊厥,每天将小鼠暴露在高热下 3 次,每次诱导惊厥之间间隔 4 小时,总共 4 天。热性惊厥的行为测试表明,与野生型(WT)小鼠相比,TRPV1 敲除小鼠模型表现出热性惊厥发作潜伏期延长、持续时间缩短和发作等级降低。WT 小鼠高热诱导热性惊厥后,TRPV1 mRNA 和蛋白的表达水平均增加。值得注意的是,TRPV1 激活导致海马和皮质中促炎细胞因子(IL-1β、IL-6、TNF-α 和 HMGB1)的表达显著升高。这些数据表明,TRPV1 表达的减少与热性惊厥易感性降低有关。因此,可以开发预防策略,用于热性惊厥期间。