Although stroke is the fourth leading cause of death in the U.S., the current treatment strategy of thrombolysis for the majority of strokes due to a blood clot (ischemic) has mixed results. Thus, there is an urgent need for new and better stroke therapies. We have previously demonstrated that the domain V protein fragment of the brain extracellular matrix component perlecan is both neuroprotective and neuroreparative after ischemic stroke by interaction with the brain endothelial cell receptor ?5?1 integrin. Intriguingy, preliminary results now suggest that mice with an endothelial selective deletion of ?5?1 integrin are profoundly resistant to experimental ischemic stroke; they show little to no signs of brain injury. Furthermore, inhibition of the ?5?1 integrin with ATN-161 or its more potent isoform Ac-PhScN-NH2 conveys nearly identical resistance to stroke injury in wild type mice. This may occur via stabilization of the blood-brain barrier through increased function of the brain endothelial cell tight junction protein claudin-5, which in turn minimizes vasogenic edema, inflammation, and injury. Therefore, we hypothesize that endothelial cell ?5?1 integrin could be a particularly effective therapeutic target for stroke. In this application, we propose the followig specific aims: 1. Determine the effect of endothelial cell selective ?5?1 integrin deletion on experimental ischemic stroke, 2. Determine the potential of the ?5?1 integrin as a therapeutic target in experimental ischemic stroke and 3. Determine, in mechanistic detail, the role of ?5?1 integrin in modulating blood-brain barrier integrity and subsequent resistance to ischemic stroke. We will use several novel genetically modified mice (?5 integrin endothelial cell specific knockdown mice, claudin5 eGFP tagged mice) and newly characterized ?5?1 integrin inhibitors in experimental stroke models and in vitro endothelial cell barrier assays. We expect to demonstrate that suppression or inhibition of ?5?1 integrin in endothelial cells affords significnt blood-brain barrier-mediated resistance to experimental ischemic stroke, supporting our long-term goal of developing ?5?1 integrin as a novel human stroke therapeutic target.

Public Health Relevance

Although stroke is the fourth leading cause of death in the U.S., current treatment options are limited in their application and efficacy. Towards that end, we have identified a novel component of the brain's injury response derived from the brain's extracellular matrix which appears to protect cells from injury and help the brain to repair itself We further showed that this component, termed perlecan domain V, exerted its beneficial effects through interaction with the ?5?1 integrin receptor on brain vascular (endothelial) cells Preliminary results now suggest that inhibition of this receptor profoundly protects the brain from stroke injury, and may do so by preventing breakdown of the blood-brain barrier. Therefore, we propose to determine the therapeutic efficacy and mechanism(s) of action of targeting the ?5?1 integrin in experimental ischemic stroke with the long term goal of developing better stroke therapies.

Agency
National Institute of Health (NIH)
Institute
National Institute of Neurological Disorders and Stroke (NINDS)
Type
Research Project (R01)
Project #
5R01NS065842-10
Application #
9233200
Study Section
Brain Injury and Neurovascular Pathologies Study Section (BINP)
Program Officer
Koenig, James I
Project Start
2010-04-01
Project End
2020-03-31
Budget Start
2017-04-01
Budget End
2018-03-31
Support Year
10
Fiscal Year
2017
Total Cost
Indirect Cost
Name
University of Kentucky
Department
Anatomy/Cell Biology
Type
Schools of Medicine
DUNS #
939017877
City
Lexington
State
KY
Country
United States
Zip Code
40526
Maniskas, Michael E; Roberts, Jill M; Trueman, Rebecca et al. (2018) Intra-arterial nitroglycerin as directed acute treatment in experimental ischemic stroke. J Neurointerv Surg 10:29-33
Roberts, Jill; de Hoog, Leon; Bix, Gregory J (2017) Mice deficient in endothelial ?5 integrin are profoundly resistant to experimental ischemic stroke. J Cereb Blood Flow Metab 37:85-96
Jullienne, Amandine; Roberts, Jill M; Pop, Viorela et al. (2014) Juvenile traumatic brain injury induces long-term perivascular matrix changes alongside amyloid-beta accumulation. J Cereb Blood Flow Metab 34:1637-45
Parham, Christi; Auckland, Lisa; Rachwal, Jessica et al. (2014) Perlecan domain V inhibits amyloid-? induced brain endothelial cell toxicity and restores angiogenic function. J Alzheimers Dis 38:415-23
Bix, Gregory J; Gowing, Emma K; Clarkson, Andrew N (2013) Perlecan domain V is neuroprotective and affords functional improvement in a photothrombotic stroke model in young and aged mice. Transl Stroke Res 4:515-23
Kahle, Michael P; Bix, Gregory J (2012) Successfully Climbing the ""STAIRs"": Surmounting Failed Translation of Experimental Ischemic Stroke Treatments. Stroke Res Treat 2012:374098
Roberts, Jill; Kahle, Michael P; Bix, Gregory J (2012) Perlecan and the blood-brain barrier: beneficial proteolysis? Front Pharmacol 3:155
Clarke, Douglas N; Al Ahmad, Abraham; Lee, Boyeon et al. (2012) Perlecan Domain V induces VEGf secretion in brain endothelial cells through integrin ?5?1 and ERK-dependent signaling pathways. PLoS One 7:e45257
Saini, Maxim G; Bix, Gregory J (2012) Oxygen-glucose deprivation (OGD) and interleukin-1 (IL-1) differentially modulate cathepsin B/L mediated generation of neuroprotective perlecan LG3 by neurons. Brain Res 1438:65-74
Kahle, Michael P; Lee, Boyeon; Pourmohamad, Tony et al. (2012) Perlecan domain V is upregulated in human brain arteriovenous malformation and could mediate the vascular endothelial growth factor effect in lesional tissue. Neuroreport 23:627-30

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