内皮细胞膜微粒通过LncRNA MIAT调控神经元Beclin-1和Caspase-3 加重脑缺血再灌注损伤的机制

Previous researches have demonstrated that endothelial cells-derived microvesicles (EMVs) involved in the occurrence and development of ischemic stroke, however, the mechanism remains less to be known. Our pilot study found that EMVs expression was so significantly elevated in ischemic stroke that exacerbate cerebral ischemic-reperfusion via modulating neuron autophagy and apoptosis. The present study plan to apply cerebral ischemic-reperfusion model of SD mouse, inanoparticle tracking analysis, transmission electron microscope, RNA fluorescence in situ hybridization, Western blot and RT-PCR, to explore the molecular mechanism underlying the cerebral ischemic-reperfusion mediated by EMVs. We aim to illuminate that elevated EMVs will increase lncRNA MIAT expression so that decrease miR-106b-5p expression via sponge effect after cerebral ischemic-reperfusion, as well as increase Becilin-2 and Caspase-3 expression to promote neuron autophage and apoptosis and exacerbate cerebral ischemic-reperfusion injury. We hope to provide new ideas and theoretical basis for neural protection after acute ischemic stroke.

研究表明内皮细胞膜微粒（EMVs）参与缺血性脑卒中发生发展，但机制不清。我们前期研究发现：循环EMVs在缺血性脑卒中患者表达显著增高，EMVs可调控神经元自噬和凋亡，加重脑缺血再灌注损伤。本项目拟采用SD大鼠脑缺血再灌注损伤模型、纳米颗粒分析仪、透射电子显微镜、RNA荧光原位杂交、Western blot及RT-PCR等技术，探讨EMVs对脑缺血再灌注损伤的影响和分子机制。验证工作假说：脑缺血再灌注损伤后，内皮细胞释放EMVs 增多，增加神经元lncRNA MIAT,通过基因海绵作用吸附miR-106b-5p，导致miR-106b-5p表达下降，从而提高Beclin-1及Caspase-3表达，促进神经元自噬及凋亡,加重脑缺血再灌注损伤。为保护脑缺血再灌注损伤提供新的思路及理论依据。

背景：研究表明内皮细胞膜微粒（EMVs）参与缺血性脑卒中发生发展，但机制不清。我们前期研究发现：循环EMVs在缺血性脑卒中患者表达显著增高，EMVs可调控神经元自噬和凋亡，加重脑缺血再灌注损伤。.方法：本项目拟采用SD大鼠脑缺血再灌注损伤模型、纳米颗粒分析仪、透射电子显微镜、RNA荧光原位杂交、Western blot及RT-PCR等技术，探讨EMVs对脑缺血再灌注损伤的影响和分子机制。.结果：我们发现：1）LncRNA MIAT不仅可作为急性缺血性脑卒中的监测指标，而且可影响神经元的自噬与凋亡从而调控脑缺血再灌注损伤；2）LncRNA MIAT可作为脑缺血再灌注损伤治疗的新靶点，LncRNA MIAT可能作用于靶点miR-106b-5p调节神经元凋亡。脑缺血再灌注后可通过下调LncRNA MIA抑制神经元损伤，缓解神经功能障碍。.结论：我们研究发现LncRNA MIAT参与脑缺血再灌注损伤的调控。在急性缺血性脑梗死中LncRNA MIAT表达升高，下调LncRNA MIAT可通过抑制神经元自噬和凋亡从而减轻脑缺血再灌注损伤，缓解神经功能障碍。LncRNA MIAT可作为脑缺血再灌注治疗的新靶点。