PDF(Pubmed)
Abstract：
Dysfunction of tight junction proteins-associated damage to the blood-brain barrier (BBB) plays an important role in the pathogenesis of ischemic stroke. Lifibrate, an inhibitor of cholinephosphotransferase (CPT), has been used as an agent for serum lipid lowering. However, the protective effects of Lifibrate in ischemic stroke and the underlying mechanism have not been clearly elucidated. Here, we employed an in vivo mice model of MCAO and an OGD/R model in vitro. In the mice models, neurological deficit scores and infarct volume were assessed. Evans Blue solution was used to detect the BBB permeability. The TEER was examined to determine brain endothelial monolayer permeability. Here, we found that Lifibrate improved neurological dysfunction in stroke. Additionally, increased BBB permeability during stroke was significantly ameliorated by Lifibrate. Correspondingly, the reduced expression of the tight junction protein ZO-1 was restored by Lifibrate at both the mRNA and protein levels. Using an in vitro model, we found that Lifibrate ameliorated OGD/R-induced injury in human bEnd.3 brain microvascular endothelial cells by increasing cell viability but reducing the release of LDH. Importantly, Lifibrate suppressed the increase in endothelial monolayer permeability and the reduction in TEER induced by OGD/R via the rescue of ZO-1 expression. Mechanistically, Lifibrate blocked activation of the MLCK/ p-MLC signaling pathway in OGD/R-stimulated bEnd.3 cells. In contrast, overexpression of MLCK abolished the protective effects of Lifibrate in endothelial monolayer permeability, TEER, as well as the expression of ZO-1. Our results provide a basis for further investigation into the neuroprotective mechanism of Lifibrate during stroke.
摘要：
紧密连接蛋白相关的血脑屏障(BBB)损伤在缺血性卒中的发病机制中起重要作用。利贝特,胆碱磷酸转移酶（CPT）的抑制剂，已被用作降血脂剂。然而,利贝特在缺血性卒中中的保护作用及其潜在机制尚未明确阐明.这里,我们采用了MCAO的体内小鼠模型和体外OGD/R模型。在小鼠模型中，评估神经功能缺损评分和梗死体积.使用伊文思蓝溶液检测BBB通透性。检查TEER以确定脑内皮单层通透性。这里,我们发现,利贝特可改善卒中患者的神经功能障碍.此外,利贝特可显著改善卒中期间BBB通透性的增加。相应地,在mRNA和蛋白质水平上,Liberpate恢复了紧密连接蛋白ZO-1的表达降低.使用体外模型，我们发现，利贝特通过增加细胞活力但减少LDH的释放，改善了OGD/R诱导的人bEnd.3脑微血管内皮细胞损伤。重要的是,通过挽救ZO-1表达，利贝特抑制了OGD/R诱导的内皮单层通透性增加和TEER降低。机械上,在OGD/R刺激的bEnd.3细胞中，利贝特阻断MLCK/p-MLC信号通路的激活。相比之下,MLCK的过度表达消除了Liberate在内皮单层通透性中的保护作用，TEER,以及ZO-1的表达。我们的结果为进一步研究利贝特在卒中的神经保护机制提供了基础。
