Complex alterations in microglial M1/M2 markers during the development of epilepsy in two mouse models
Complex alterations in microglial M1/M2 markers during the development of epilepsy in two mouse models
复制标题
DOI：
10.1111/epi.12960
复制
发表时间：
2015-06-01
期刊：
影响因子：
5.6
通讯作者：
Borges, Karin
中科院分区：
文献类型：
--
作者：
Benson, Melissa J.;Manzanero, Silvia;Borges, Karin
目的研究慢性匹罗卡品致痫小胶质细胞M1和抗炎M2标志物表达的变化。方法M1激活的小胶质细胞表达促炎细胞因子，而M2激活的小胶质细胞更具修复性，促进碎片的吞噬和与细胞稳定和修复相关的蛋白的表达。小胶质细胞标志物表现为急性(癫痫持续状态后3d)、早期慢性(癫痫持续状态后21d)和慢性癫痫晚期(癫痫持续状态后5~12个月)时间点。匹罗卡品SE后，用流式细胞仪检测小胶质细胞标志物的表达。用实时定量聚合酶链式反应(RT-PCR)检测炎症区[FIZZ-1][FIZZ-1][FIZZ-3类蛋白[YM1]，IL-1[FIZZ-1]，甘露糖受体C型[CD206]，白介素4[IL-4]，白介素6[IL-6]，白介素12[IL-12]，Fc受体16，CD86；M_2[精氨酸酶1]，几丁质酶-3样蛋白[Y_1]，甘露糖受体-1[CD206]，[IL-4]，和白介素10(IL-10)标志物)。结果匹罗卡品癫痫模型大鼠SE后3d小胶质细胞表达M1和M2标志物，而海人藻酸诱导的SE后仅M1标志物表达上调。3周后，两种模型大鼠海马区M1/M2标志物的表达均基本消失。在匹罗卡品模型中，CD11b、胶质纤维酸性蛋白(GFAP)和IL-1的mRNA水平略有升高，与IL-1在自发性癫痫发作中的作用一致，而TNF和YM1的mRNA水平降低。在慢性期的晚期，一些M1/M2标记物，IL-1、肿瘤坏死因子、Arg1、YM1和CD206在海人酸组中重新出现，但在匹罗卡品模型中没有，这可能反映和/或导致海人酸样癫痫小鼠高频率的癫痫发作。意义通常的M1在癫痫发作后急剧上调，可能在癫痫发生的早期发出信号，在海人酸样癫痫后中枢神经系统处于更纯粹的炎症状态，可能导致更频繁的癫痫发作的发展。这种差异也可能是由于匹罗卡品注射后的外周炎症所致。总而言之，癫痫发生过程中的小胶质细胞炎症反应是复杂的，在不同的模型中是不同的，并且似乎与慢性癫痫发作频率有关。
ObjectiveTo characterize the changes in microglial proinflammatory M1 and antiinflammatory M2 marker expression during epileptogenesis in the chronic pilocarpine and intrahippocampal kainate models.MethodsM1-activated microglia express proinflammatory cytokines driving infiltration of cells, whereas M2-activated microglia are more reparative, promoting phagocytosis of debris and expression of proteins associated with cellular stability and repair. Microglial markers were characterized as acute (3days after status epilepticus [SE]), early chronic (21days post-SE), and late chronic epileptic (5-12months post-SE) time points. Following pilocarpine-SE, microglial markers were assessed by flow cytometry. Quantitative real-time polymerase chain reaction (RT-PCR) was used to measure messenger RNA (mRNA) levels of selected M1 (interleukin [IL] 1, tumor necrosis factor [TNF] cluster of differentiation [CD],CD16, and CD86), interleukin-6 [IL-6], interleukin-12 [IL-12], Fc receptors 16, and CD86) and M2 (arginase 1 [Arg1], chitinase-3-like protein [Ym1], found in inflammatory zone [FIZZ-1] [FIZZ-1], mannose receptor C type-1 [CD206], interleukin-4 [IL-4], and interleukin-10 (IL-10)) markers in both models. Video-electroencephalography (EEG) recordings were used to quantify late chronic seizure frequency.ResultsThree days post-SE microglia in the pilocarpine model expressed M1 and M2 markers, but only M1 markers were upregulated after kainate-induced SE. After 3weeks, M1/M2 marker expression was largely ablated in the hippocampal formation of both models. Small mRNA level increases of CD11b, glial fibrillary acidic protein (GFAP), and IL-1 were found in the pilocarpine model, consistent with IL-1 contributing to spontaneous seizures, whereas mRNA levels of TNF and Ym1 were decreased. In the late chronic phase, some M1/M2 markers, IL-1, TNF, Arg1, Ym1, and CD206, resurged in the kainate, but not pilocarpine model, which may reflect and/or contribute to highly frequent seizures in kainate-SE mice.SignificanceThe common M1 upregulation acutely post-SE may signal a role early in epileptogenesis, with a more pure inflamed central nervous system state after kainate-SE, potentially contributing to the development of more frequent seizures. The difference may also be due to the contribution of peripheral inflammation after pilocarpine injection. In summary, the microglial inflammatory response during epileptogenesis is complex, varies between models, and appears to correlate with chronic seizure frequency.