Integrin Beta 4E Promotes Endothelial Phenotypic Changes and Attenuates Lung Endothelial Cell Inflammatory Responses
AffiliationDepartment of Cellular and Molecular Medicine, University of Arizona
Department of Medicine, University of Arizona Health Sciences
MetadataShow full item record
PublisherFrontiers Media S.A.
CitationChen, W., Gard, J. M. C., Epshtein, Y., Camp, S. M., Garcia, J. G. N., Jacobson, J. R., & Cress, A. E. (2022). Integrin Beta 4E Promotes Endothelial Phenotypic Changes and Attenuates Lung Endothelial Cell Inflammatory Responses. Frontiers in Physiology.
JournalFrontiers in Physiology
RightsCopyright © 2022 Chen, Gard, Epshtein, Camp, Garcia, Jacobson and Cress. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY).
Collection InformationThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at email@example.com.
AbstractWe previously reported integrin beta 4 (ITGB4) is an important mediator of lung vascular protection by simvastatin, a 3-hydroxy-3-methylglutaryl-coenzyme A-reductase inhibitor. In this study, we report increased endothelial cell (EC) expression specifically of ITGB4E, an ITGB4 mRNA splice variant, by simvastatin with effects on EC protein expression and inflammatory responses. In initial experiments, human pulmonary artery ECs were treated using simvastatin (5 μM, 24 h) prior to immunoprecipitation of integrin alpha 6 (ITGA6), which associates with ITGB4, and Western blotting for full-length ITGB4 and ITGB4E, uniquely characterized by a truncated 114 amino acid cytoplasmic domain. These experiments confirmed a significant increase in both full-length ITGB4 and ITGB4E. To investigate the effects of increased ITGB4E expression alone, ECs were transfected with ITGB4E or control vector, and cells were seeded in wells containing Matrigel to assess effects on angiogenesis or used for scratch assay to assess migration. Decreased angiogenesis and migration were observed in ITGB4E transfected ECs compared with controls. In separate experiments, PCR and Western blots from transfected cells demonstrated significant changes in EC protein expression associated with increased ITGB4E, including marked decreases in platelet endothelial cell adhesion molecule-1 (PECAM-1) and vascular endothelial-cadherin (VE-cadherin) as well as increased expression of E-cadherin and N-cadherin along with increased expression of the Slug and Snail transcription factors that promote endothelial-to-mesenchymal transition (EndMT). We, then, investigated the functional effects of ITGB4E overexpression on EC inflammatory responses and observed a significant attenuation of lipopolysaccharide (LPS)-induced mitogen-activated protein kinase (MAPK) activation, including decreased phosphorylation of both extracellular signal-regulated kinase (ERK) and c-Jun N-terminal kinase (JNK), as well as reduced inflammatory cytokines (IL-6 and IL-8), expressed in the media of EC after either LPS or excessive cyclic stretch (CS). Finally, EC expression-increased ITGB4E demonstrated decreased barrier disruption induced by thrombin as measured by transendothelial electrical resistance. Our data support distinct EC phenotypic changes induced by ITGB4E that are also associated with an attenuation of cellular inflammatory responses. These findings implicate ITGB4E upregulation as an important mediator of lung EC protection by statins and may lead to novel therapeutic strategies for patients with or at risk for acute lung injury (ALI). Copyright © 2022 Chen, Gard, Epshtein, Camp, Garcia, Jacobson and Cress.
NoteOpen access journal
VersionFinal published version
Except where otherwise noted, this item's license is described as Copyright © 2022 Chen, Gard, Epshtein, Camp, Garcia, Jacobson and Cress. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY).