Department of Pharmacy, Affiliated Hospital of Nantong University, 226001 Nantong, Jiangsu, China.
Department of Pathology, Affiliated Hospital of Nantong University, 226001 Nantong, Jiangsu, China.
J Integr Neurosci. 2024 Jul 5;23(7):124. doi: 10.31083/j.jin2307124.
Endothelial-to-mesenchymal transition (EndoMT) is a significant biological phenomenon wherein endothelial cells undergo a loss of their endothelial traits and progressively acquire mesenchymal characteristics. Consequently, this transformation leads to both a compromised ability to maintain lumen permeability and alterations in vascular structure, which hampers the preservation of blood-brain barrier integrity. This study aimed to investigate inflammation-induced EndoMT and its etiology, with the goal of impeding the infiltration of peripheral inflammation into the central nervous system.
Lipolysaccharide (LPS) was administered intraperitoneally to mice several times to establish a chronic inflammatory model. A cellular inflammatory model was established by LPS in human brain microvascular endothelial cells (HBMECs). The mRNA expressions of inflammatory cytokines interleukin-1β () and were detected by real-time polymerase chain reaction (PCR). Immunofluorescence staining of platelet endothelial cell adhesion molecule-1 (CD31) and alpha smooth muscle actin (α-SMA) was conducted to assess the level of EndoMT. The expression levels of Occludin, zona occludens protein 1 (ZO-1), Sestrin2, microtubule-associated protein1 light chain 3 (LC3) and inducible nitric oxide synthase (iNOS) were detected by western blotting.
LPS treatment induced the downregulation of ZO-1 and Occludin, which was accompanied by the elevated expressions of iNOS, α-SMA, Sestrin2 and LC3-II in the mouse cortex and HBMECs. Mechanistically, the knockdown of in HBMECs exacerbated the EndoMT induced by LPS treatment, while the overexpression of inhibited this process. Moreover, the induction of autophagy by rapamycin rescued the EndoMT induced by knockdown.
This study revealed that Sestrin2 inhibited endothelial inflammation and EndoMT via enhanced autophagy, which may provide a potential drug target for cerebrovascular inflammatory injury.
内皮细胞向间充质转化（EndoMT）是一种重要的生物学现象，在此过程中内皮细胞丧失内皮特性，并逐渐获得间充质特征。因此，这种转化导致内皮细胞维持管腔通透性的能力受损，并改变血管结构，从而破坏血脑屏障的完整性。本研究旨在探讨炎症诱导的 EndoMT 及其病因，以期阻止外周炎症渗透到中枢神经系统。
多次腹腔内给予脂多糖（LPS）建立慢性炎症模型。LPS 建立人脑微血管内皮细胞（HBMEC）的细胞炎症模型。实时聚合酶链反应（PCR）检测炎症细胞因子白细胞介素 1β（）和 的 mRNA 表达。血小板内皮细胞黏附分子 1（CD31）和α平滑肌肌动蛋白（α-SMA）的免疫荧光染色评估 EndoMT 水平。Western blot 检测紧密连接蛋白 Occludin、封闭蛋白 1（ZO-1）、Sesnrin2、微管相关蛋白 1 轻链 3（LC3）和诱导型一氧化氮合酶（iNOS）的表达水平。
LPS 处理诱导小鼠皮质和 HBMECs 中 ZO-1 和 Occludin 下调，同时 iNOS、α-SMA、Sesnrin2 和 LC3-II 表达上调。机制上，HBMECs 中 敲低加剧了 LPS 诱导的 EndoMT，而过表达 则抑制了这一过程。此外，雷帕霉素诱导的自噬挽救了 敲低诱导的 EndoMT。
本研究表明，Sesnrin2 通过增强自噬抑制内皮炎症和 EndoMT，这可能为脑血管炎症损伤提供潜在的药物靶点。
