基于miR-23a/GSDME轴探讨绝经后缺血性脑卒中神经元焦亡机制及加味脑泰方的干预作用

Postmenopausal ischemic stroke has seriously endangered women's life and health.Previous studies have found that the estrogen level and the changes of signal pathways after estrogen receptor (ER) are closely related to brain damage in postmenopausal ischemic stroke.The degree of cerebral ischemia of ovariectomized rats with cerebral ischemia was more serious than that of rats with cerebral ischemia,and the numbers of neuronal cell death of ovariectomized rats with cerebral ischemia were more than that of rats with cerebral ischemia,and the expression of Gasdermin E (GSDME) of hippocampus in ovariectomized rats with cerebral ischemia was up-regulated.Jiawei Naotaifang with the effect of nourishing Yin, invigorating Qi and activating blood circulation could can protect brain by up-regulating ER,etc. Recently,pyroptosis has attracted much attention in ischemic brain injury.The microRNA-23a/GSDME axis associated with pyroptosis has a significant correlation with ER.Therefore,this project puts forward hypothesis:Jiawei Naotaifang regulates the microRNA-23a/GSDME axis by up-regulating the expression of ER,and inhibits neuronal pyroptosis,and achieve anti-ischemic brain injury.The objects of this project were the ovariectomized rats with cerebral ischemia and oxygen glucose deprivation（OGD）model hippocampal neurons.The purpose of this project is to explore the relationship between ER regulation of pyroptosis induced by microRNA-23a/GSDME axis and ischemic brain injury,and the intervention effect of Jiawei Naotaifang. The mechanism of Jiawei Naotaifang in preventing postmenopausal ischemic brain injury is elucidated from the perspective of regulating cell pyroptosis by post-ER signal transduction pathway. At the same time, it is elucidate that the method of nourishing Yin, invigorating Qi and activating blood circulation improves postmenopausal ischemic brain injury,which provides a new idea and basis for clinical treatment of postmenopausal cerebral infarction.

绝经后缺血性脑卒中严重危害女性的生命健康。前期研究发现雌激素水平及其受体（ER）后变化与绝经后缺血性脑损伤密切相关；去势后大鼠脑缺血加重，神经元死亡增多，海马Gasdermin E（GSDME）等表达上调；滋阴益气活血功效的加味脑泰方可通过上调ER等发挥脑保护作用。新近细胞焦亡在缺血性脑损伤中备受关注，焦亡相关的miR-23a/GSDME轴与ER具有显著关联性。由此，本课题提出假说：加味脑泰方通过上调ER表达调控miR-23a/GSDME轴，以抑制神经细胞焦亡从而抗缺血性脑损伤作用。拟以去势脑缺血模型大鼠、氧糖剥夺模型海马神经元为研究对象，探讨ER调控miR-23a/GSDME轴诱导焦亡与缺血性脑损伤的关系及加味脑泰方干预作用，从ER后信号传导通路调控细胞焦亡的角度阐明加味脑泰方抗绝经后缺血性脑损伤的作用机制，同时为阐明滋阴益气活血法改善绝经后脑缺血损伤提供新思路和新依据。

我国是世界上脑卒中负担最重的国家之一，缺血性脑卒中是主要的类型，缺血性脑损伤与细胞死亡密切相关，而细胞焦亡是一种新发现的程序性细胞死亡方式。本项目拟研究去势脑缺血（去双侧卵巢脑缺血）大鼠海马神经细胞焦亡及雌激素受体后信号调控的规律，加味脑泰方对去势脑缺血大鼠海马神经细胞焦亡及雌激素受体后信号调控的影响，miR-23a/GSDME轴诱导去势脑缺血大鼠海马神经细胞焦亡与雌激素受体的相关性及加味脑泰方的干预作用。目的是明确去势脑缺血大鼠海马神经细胞焦亡机制，以及加味脑泰方的作用机制。实验结果发现：去势脑缺血大鼠神经功能评分、梗死面积明显增大，电镜观察发现胞质胞膜有不同程度的破裂损伤、内容物降减且呈不均匀分布、大小不等的水泡形成、存在线粒体损伤，PI细胞阳性率增加，血雌激素水平明显下降、FSH明显上升，海马ERa、XIAP mRNA下调，GSDME、GSDME-N、miR-23a mRNA上调。去势脑缺血模型（去双侧卵巢脑缺血）大鼠侧脑室给予雌激素受体抑制剂后干预，海马ERa、XIAP 表达下调，GSDME、GSDME-N、miR-23a 表达上调；给予miR-23a抑制剂、Z-DEVD-FMK、加味脑泰方干预后，可逆转以上基因/蛋白的表达。通过本项目的研究，发现了去势脑缺血大鼠海马神经细胞发生焦亡，同时miR-23a/GSDME轴可介导焦亡的发生，而加味脑泰方可通过雌激素受体调控miR-23a/GSDME轴，进一步抑制神经细胞焦亡，为女性绝经后脑缺血的发病机制及防治思路的研究提供新的策略。