Academic Unit of Mental Health and Clinical Neuroscience, Clinical Sciences Building, School of Medicine, The University of Nottingham, Hucknall Road, Nottingham, NG5 1PB, UK.
Stem Cell Rev Rep. 2023 Feb;19(2):503-515. doi: 10.1007/s12015-022-10439-4. Epub 2022 Sep 2.
Improved understanding of the key mechanisms underlying cerebral ischemic injury is essential for the discovery of efficacious novel therapeutics for stroke. Through detailed analysis of plasma samples obtained from a large number of healthy volunteers (n = 90) and ischemic stroke patients (n = 81), the current study found significant elevations in the levels of TNF-α at baseline (within the first 48 h of stroke) and on days 7, 30, 90 after ischaemic stroke. It then assessed the impact of this inflammatory cytokine on an in vitro model of human blood-brain barrier (BBB) and revealed dramatic impairments in both barrier integrity and function, the main cause of early death after an ischemic stroke. Co-treatment of BBB models in similar experiments with outgrowth endothelial cell-derived conditioned media (OEC-CM) negated the deleterious effects of TNF-α on BBB. Effective suppression of anti-angiogenic factor endostatin, stress fiber formation, oxidative stress, and apoptosis along with concomitant improvements in extracellular matrix adhesive and tubulogenic properties of brain microvascular endothelial cells and OECs played an important role in OEC-CM-mediated benefits. Significant increases in pro-angiogenic endothelin-1 and monocyte chemoattractant protein-1 in OEC-CM compared to the secretomes of OEC and HBMEC, detected by proteome profiling assay, accentuate the beneficial effects of OEC-CM. In conclusion, this reverse translational study identifies TNF-α as an important mediator of post-ischemic cerebral barrier damage and proposes OEC-CM as a potential vasculoprotective therapeutic strategy by demonstrating its ability to regulate a wide range of mechanisms associated with BBB function. Clinical trial registration NCT02980354.
通过对大量健康志愿者（n=90）和缺血性脑卒中患者（n=81）的血浆样本进行详细分析，本研究发现，在脑卒中发生后第 48 小时内及第 7、30、90 天，TNF-α的基线水平（脑卒中后最初 48 小时内）显著升高。随后，研究评估了这种炎症细胞因子对体外人血脑屏障（BBB）模型的影响，结果显示，TNF-α导致 BBB 的完整性和功能严重受损，这是缺血性脑卒中后早期死亡的主要原因。在类似的实验中，用体外生长的血管内皮细胞衍生条件培养基（OEC-CM）对 BBB 模型进行共处理，可消除 TNF-α对 BBB 的有害影响。在大脑微血管内皮细胞和 OEC 中，抗血管生成因子内皮抑素、应激纤维形成、氧化应激和细胞凋亡的有效抑制，以及细胞外基质黏附性和管状形成特性的同时改善，在 OEC-CM 介导的益处中发挥了重要作用。与 OEC 和 HBMEC 的分泌组相比，OEC-CM 中的促血管生成内皮素-1 和单核细胞趋化蛋白-1 显著增加，通过蛋白质组分析检测到，这突出了 OEC-CM 的有益作用。总之，这项转化研究将 TNF-α确定为缺血后大脑屏障损伤的重要介质，并通过证明其调节与 BBB 功能相关的广泛机制的能力，提出了 OEC-CM 作为一种潜在的血管保护治疗策略。临床试验注册 NCT02980354。
