Regulation and release of vasoactive endoglin by brain endothelium in response to hypoxia/reoxygenation in stroke

Please always quote using this URN: urn:nbn:de:bvb:20-opus-284361
  • In large vessel occlusion stroke, recanalization to restore cerebral perfusion is essential but not necessarily sufficient for a favorable outcome. Paradoxically, in some patients, reperfusion carries the risk of increased tissue damage and cerebral hemorrhage. Experimental and clinical data suggest that endothelial cells, representing the interface for detrimental platelet and leukocyte responses, likely play a crucial role in the phenomenon referred to as ischemia/reperfusion (I/R)-injury, but the mechanisms are unknown. We aimed to determineIn large vessel occlusion stroke, recanalization to restore cerebral perfusion is essential but not necessarily sufficient for a favorable outcome. Paradoxically, in some patients, reperfusion carries the risk of increased tissue damage and cerebral hemorrhage. Experimental and clinical data suggest that endothelial cells, representing the interface for detrimental platelet and leukocyte responses, likely play a crucial role in the phenomenon referred to as ischemia/reperfusion (I/R)-injury, but the mechanisms are unknown. We aimed to determine the role of endoglin in cerebral I/R-injury; endoglin is a membrane-bound protein abundantly expressed by endothelial cells that has previously been shown to be involved in the maintenance of vascular homeostasis. We investigated the expression of membranous endoglin (using Western blotting and RT-PCR) and the generation of soluble endoglin (using an enzyme-linked immunosorbent assay of cell culture supernatants) after hypoxia and subsequent reoxygenation in human non-immortalized brain endothelial cells. To validate these in vitro data, we additionally examined endoglin expression in an intraluminal monofilament model of permanent and transient middle cerebral artery occlusion in mice. Subsequently, the effects of recombinant human soluble endoglin were assessed by label-free impedance-based measurement of endothelial monolayer integrity (using the xCELLigence DP system) and immunocytochemistry. Endoglin expression is highly inducible by hypoxia in human brain endothelial monolayers in vitro, and subsequent reoxygenation induced its shedding. These findings were corroborated in mice during MCAO; an upregulation of endoglin was displayed in the infarcted hemispheres under occlusion, whereas endoglin expression was significantly diminished after transient MCAO, which is indicative of shedding. Of note is the finding that soluble endoglin induced an inflammatory phenotype in endothelial monolayers. The treatment of HBMEC with endoglin resulted in a decrease in transendothelial resistance and the downregulation of VE-cadherin. Our data establish a novel mechanism in which hypoxia triggers the initial endothelial upregulation of endoglin and subsequent reoxygenation triggers its release as a vasoactive mediator that, when rinsed into adjacent vascular beds after recanalization, can contribute to cerebral reperfusion injury.show moreshow less

Download full text files

Export metadata

Additional Services

Share in Twitter Search Google Scholar Statistics
Metadaten
Author: Axel Haarmann, Lena Zimmermann, Michael Bieber, Christine Silwedel, Guido Stoll, Michael K. Schuhmann
URN:urn:nbn:de:bvb:20-opus-284361
Document Type:Journal article
Faculties:Medizinische Fakultät / Kinderklinik und Poliklinik
Medizinische Fakultät / Neurologische Klinik und Poliklinik
Language:English
Parent Title (English):International Journal of Molecular Sciences
ISSN:1422-0067
Year of Completion:2022
Volume:23
Issue:13
Article Number:7085
Source:International Journal of Molecular Sciences (2022) 23:13, 7085. doi:10.3390/ijms23137085
DOI:https://doi.org/10.3390/ijms23137085
Dewey Decimal Classification:6 Technik, Medizin, angewandte Wissenschaften / 61 Medizin und Gesundheit / 610 Medizin und Gesundheit
Tag:CD105; HBMEC; endoglin; human brain endothelium; hypoxia; ischemia/reperfusion injury; middle cerebral artery occlusion; reoxygenation; soluble endoglin; stroke; vascular homeostasis
Release Date:2023/04/19
Date of first Publication:2022/06/25
Open-Access-Publikationsfonds / Förderzeitraum 2022
Licence (German):License LogoCC BY: Creative-Commons-Lizenz: Namensnennung 4.0 International