全世界有超过七千万人患有癫痫,大多数经历癫痫发作在儿童时期。尽管有20多种抗癫痫药物,约30%的癫痫患者继续经历不令人满意的治疗结果.这种情况给患者的家庭和社会带来了沉重的负担。儿童癫痫是一种重要的慢性神经系统疾病,与遗传学密切相关。Col4a2,编码IV型胶原α2链的基因,已知由于错义突变而与多种疾病相关。胶原IV型的Col4a2变体与各种表型有关,包括产前和新生儿颅内出血,头颅后,患有白内障的头畸形,局灶性皮质发育不良,脑裂,童年和青春期的中风,和偶发性迟发性出血性中风.尽管癫痫被认为是头颅后畸形的临床表现,Col4a2相关癫痫表型的具体机制尚不清楚.对8例2岁2个月至18岁诊断为Col4a2相关性小儿癫痫痉挛综合征的患者进行分析。癫痫发作年龄3~10个月。最初的EEG结果显示心律失常或多焦点和多焦点尖锐波,尖峰波,尖锐的慢波,或尖峰慢波。在这些患者的脑脊液中检测到细胞因子IL-1β(32.23±12.58pg/ml)和IL-6(45.12±16.03pg/ml)的水平升高,没有任何感染迹象。抗癫痫治疗后,当癫痫发作得到控制时,脑脊液中IL-1β和IL-6水平降低。此外,我们旨在研究Col4a2突变在癫痫发生中的作用.通过使用免疫荧光测定,ELISA,和西方印迹,我们检查了星形胶质细胞活性和炎症细胞因子如IL-1β的表达,在CTX-TNA细胞和原代星形胶质细胞中过表达未报道的Col4a2(c.1838G>T)突变体后的IL-6和TNF-α。我们发现炎症因子IL-1β的水平,IL-6和TNF-α在CTX-TNA细胞(ELISA:分别为p=0.0087,p<0.001,p<0.001)和原代星形胶质细胞(ELISA:分别为p=0.0275,p<0.001,p<0.001)中均增加。此外,我们对JAK/STAT通路在Col4a2突变相关癫痫中的作用进行了初步研究.Col4a2突变刺激星形胶质细胞激活,增加iNOS,COX-2,IL-1β,CTX-TNA细胞和原代星形胶质细胞中IL-6和TNF-α水平。这种突变也激活了JAK/STAT信号通路,导致JAK2和STAT3磷酸化增加。用JAK/STAT抑制剂WP1066处理有效地抵消了原代星形胶质细胞和CTX-TNA细胞中的这种作用。迄今为止,已知突变会导致发育性和癫痫性脑病(DEE)的基因根据功能主要分为6种亚型.我们的研究表明,一个未报告的突变位点Col4a2Mut(c.1838G>T)可以引起神经炎症,可能是VII型DEE基因。
There are more than 70 million people worldwide living with epilepsy, with most experiencing the onset of epilepsy in childhood. Despite the availability of more than 20 anti-seizure medications, approximately 30% of epilepsy patients continue to experience unsatisfactory treatment outcomes. This situation places a heavy burden on patients\' families and society. Childhood epilepsy is a significant chronic neurological disease that is closely related to genetics.
Col4a2, the gene encoding the α2 chain of type IV collagen, is known to be associated with multiple diseases due to missense mutations. The
Col4a2 variant of collagen type IV is associated with various phenotypes, including prenatal and neonatal intracranial hemorrhage, porencephaly, porencephaly with cataracts, focal cortical dysplasia, schizencephaly, strokes in childhood and adolescence, and sporadic delayed hemorrhagic stroke. Although epilepsy is recognized as a clinical manifestation of porencephaly, the specific mechanism of Col4a2-related epileptic phenotypes remains unclear. A total of 8 patients aged 2 years and 2 months to 18 years who were diagnosed with Col4a2-related infantile epileptic spasm syndrome were analyzed. The seizure onset age ranged from 3 to 10 months. Initial EEG results revealed hypsarrhythmia or multiple and multifocal sharp waves, spike waves, sharp slow waves, or spike slow waves. Elevated levels of the cytokines IL-1β (32.23±12.58 pg/ml) and IL-6 (45.12±16.03 pg/ml) were detected in the cerebrospinal fluid of these patients without any signs of infection. Following antiseizure treatment, decreased IL-1β and IL-6 levels in the cerebrospinal fluid were noted when seizures were under control. Furthermore, we aimed to investigate the role of
Col4a2 mutations in the development of epilepsy. Through the use of immunofluorescence assays, ELISA, and Western blotting, we examined astrocyte activity and the expression of inflammatory cytokines such as IL-1β, IL-6, and TNF-α after overexpressing an unreported Col4a2 (c.1838G>T) mutant in CTX-TNA cells and primary astrocytes. We found that the levels of the inflammatory factors IL-1β, IL-6, and TNF-α were increased in both CTX-TNA cells (ELISA: p = 0.0087, p<0.001, p<0.001, respectively) and primary astrocytes (ELISA: p = 0.0275, p<0.001, p<0.001, respectively). Additionally, we conducted a preliminary investigation of the role of the JAK/STAT pathway in
Col4a2 mutation-associated epilepsy.
Col4a2 mutation stimulated astrocyte activation, increasing iNOS, COX-2, IL-1β, IL-6, and TNF-α levels in both CTX-TNA cells and primary astrocytes. This mutation also activated the JAK/STAT signaling pathway, leading to increased phosphorylation of JAK2 and STAT3. Treatment with the JAK/STAT inhibitor WP1066 effectively counteracted this effect in primary astrocytes and CTX-TNA cells. To date, the genes who mutations are known to cause developmental and epileptic encephalopathies (DEEs) are predominantly grouped into six subtypes according to function. Our study revealed that an unreported mutation site Col4a2Mut (c.1838G>T) of which can cause neuroinflammation, may be a type VII DEE-causing gene.