LncRNA作为tPA治疗缺血性脑卒中后出血转化标志物及其调控机制与靶向治疗

缺血性脑卒中（IS）tPA溶栓治疗增加出血转化（HT）风险，HT可导致死亡率增高与不良预后。因此寻找早期分子标志物及阐明其分子机制至关重要。长链非编码RNA（lncRNA）在IS发生发展和血脑屏障（BBB）破坏中起到重要的调控作用。我们前期筛选出tPA溶栓后特别是发生HT的IS患者血清高表达的lncRNA-XR-946182（在此命名为lncRNA-HT1），并证明了其通过星形胶质细胞外泌体参与BBB破坏。本课题关键科学问题为“lncRNA-HT1作为tPA治疗IS后HT标志物及其调控机制与靶向治疗”。拟首先验证lncRNA-HT1与IS溶栓后HT的关系，评估其作为血清标志物的潜能，进一步阐明lncRNA-HT1及星形胶质细胞外泌体调控BBB破坏的分子机制；最后利用铁蛋白纳米颗粒靶向投递lncRNA-HT1小干扰RNA保护BBB减少HT发生。该项目将为IS溶栓后HT提供新靶标和干预策略。

Thrombolytic therapy using tPA in clinical can lead to higher risk of hemorrhage transformation (HT) in patients with ischemic stroke (IS), which is considered to be associated with the disruption of blood brain barrier (BBB) caused by tPA. We previously reported that in addition to thrombolytic and neuroprotective effects, tPA also destroys the integrity of the BBB, and this effect is independent of proteolytic activity. In order to further study its mechanism, we identified a long non-coding RNA (lncRNA)-XR-946182 (named lncRNA-HT1 in this project) by RNA microarray, which is highly expressed in the serum of IS patients treated by tPA and associated with HT. Thus lncRNA-HT1 can serve as a serum biomarker of HT and a promising therapeutic target. In addition, lncRNA-HT1 was also highly expressed in astrocytes and astrocyte derived exosomes after tPA treatment in the condition of ischemic reperfusion. Exosomes derived from astrocytes after ischemic reperfusion and tPA treatment increased BBB permeability in vitro, while this effect could be attenuated by knock-down of lncRNA-HT1. This project focuses on "lncRNA-HT1 act as a marker of HT after tPA treatment in ischemic stroke and its mechanism and targeted therapy". This project will first verify the role of lncRNA-HT1 in regulating HT after tPA treatment and evaluate its potential value of acting as a biomarker of tPA associated HT, further clarify the mechanism of lncRNA-HT1 and astrocyte exosomes in regulating BBB disruption after tPA therapy, and finally assess the effects of the targeted delivery of therapeutic lncRNA-HT1 siRNA ferritin nanoparticles on the protection of BBB and the reduction of HT after tPA treatment. This study can not only further reveal the mechanism of HT caused by tPA treatment, but aslo provide a new target of diagnosis, treatment and prognosis, as well as a useful intervention strategy for clinical use.