Regulation of Thrombin-Induced Lung Endothelial Cell Barrier Disruption by Protein Kinase C Delta.

TitleRegulation of Thrombin-Induced Lung Endothelial Cell Barrier Disruption by Protein Kinase C Delta.
Publication TypeJournal Article
Year of Publication2016
AuthorsXie L, Chiang ET, Wu X, Kelly GT, Kanteti P, Singleton PA, Camp SM, Zhou T, Dudek SM, Natarajan V, Wang T, Black SM, Garcia JGN, Jacobson JR
JournalPLoS One
Date Published2016
ISSN Number1932-6203
KeywordsAcetophenones, Benzopyrans, Endothelial Cells, Enzyme Activation, Gene Silencing, Humans, Lung, Models, Biological, Myosin Light Chains, Phosphoprotein Phosphatases, Phosphorylation, Protein Kinase C, Protein Kinase C-delta, rho GTP-Binding Proteins, Signal Transduction, Stress Fibers, Thrombin

<p>Protein Kinase C (PKC) plays a significant role in thrombin-induced loss of endothelial cell (EC) barrier integrity; however, the existence of more than 10 isozymes of PKC and tissue-specific isoform expression has limited our understanding of this important second messenger in vascular homeostasis. In this study, we show that PKCδ isoform promotes thrombin-induced loss of human pulmonary artery EC barrier integrity, findings substantiated by PKCδ inhibitory studies (rottlerin), dominant negative PKCδ construct and PKCδ silencing (siRNA). In addition, we identified PKCδ as a signaling mediator upstream of both thrombin-induced MLC phosphorylation and Rho GTPase activation affecting stress fiber formation, cell contraction and loss of EC barrier integrity. Our inhibitor-based studies indicate that thrombin-induced PKCδ activation exerts a positive feedback on Rho GTPase activation and contributes to Rac1 GTPase inhibition. Moreover, PKD (or PKCμ) and CPI-17, two known PKCδ targets, were found to be activated by PKCδ in EC and served as modulators of cytoskeleton rearrangement. These studies clarify the role of PKCδ in EC cytoskeleton regulation, and highlight PKCδ as a therapeutic target in inflammatory lung disorders, characterized by the loss of barrier integrity, such as acute lung injury and sepsis.</p>

Alternate JournalPLoS ONE
PubMed ID27442243
PubMed Central IDPMC4956111
Grant ListP01 HL098050 / HL / NHLBI NIH HHS / United States
P01 HL101902 / HL / NHLBI NIH HHS / United States
R01 HL060190 / HL / NHLBI NIH HHS / United States
R01 HL067841 / HL / NHLBI NIH HHS / United States