Inhibition of integrin alphavbeta3 ameliorates focal cerebral ischemic damage in the rat middle cerebral artery occlusion model.
OBJECTIVE
Recent studies have shown that selective inhibition of specific subsets of intercellular adhesion molecules protects the brain during ischemia. We studied selective inhibition of integrin alphavbeta3 with cyclo [Arg-Gly-Asp-D-Phe-Val] (cRGDfV) in the rat middle cerebral artery occlusion model (MCAO).


METHODS
Rats were treated before and after MCAO with cRGDfV. Physiological parameters, expression of integrin alphavbeta3, infarction volume, brain water content, Evans Blue exudation, IgG exudation, histology, immunohistochemistry, and western blotting were studied in 4 groups of animals: sham operation (n=13), untreated (n=18), nonfunctioning peptide treatment (n=19), and cRGDfV treatment (n=27).


RESULTS
Treatment with cRGDfV reduced infarction, reduced brain edema, reduced exudation of Evans blue and IgG, and prevented fibrinogen deposition. Western blotting showed reduction of phosphorylated Flk-1 (a vascular endothelial growth factor [VEGF] receptor), reduction of phosphorylated FAK (an intracellular kinase phosphorylated in the presence of VEGF), reduction of VEGF, and reduction of fibrinogen in the cRGDfV treatment group.


CONCLUSIONS
The selective integrin alphavbeta3 inhibitor cRGDfV improves outcomes in the MCAO model by preserving the blood-brain barrier, which mechanistically may occur in a VEGF- and VEGF-receptor-dependent manner.
Shimamura
Norihito
N
Department of Physiology & Pharmacology, Loma Linda University School of Medicine, Loma Linda, Calif 92350, USA.
Matchett
Gerald
G
Yatsushige
Hiroshi
H
Calvert
John W
JW
Ohkuma
Hiroki
H
Zhang
John
J
D000818:Animals; D001812:Blood-Brain Barrier / Q000187:drug effects; D001929:Brain Edema / Q000209:etiology / Q000473:pathology / Q000517:prevention & control; D002544:Cerebral Infarction / Q000209:etiology / Q000473:pathology / Q000517:prevention & control; D004353:Drug Evaluation, Preclinical; D005070:Evans Blue / Q000493:pharmacokinetics; D005119:Extravasation of Diagnostic and Therapeutic Materials / Q000517:prevention & control; D005340:Fibrinogen / Q000032:analysis; D051417:Focal Adhesion Kinase 1 / Q000378:metabolism; D020244:Infarction, Middle Cerebral Artery / Q000150:complications / Q000188:drug therapy* / Q000473:pathology / Q000503:physiopathology; D039302:Integrin alphaVbeta3 / Q000037:antagonists & inhibitors*; D008297:Male; D023421:Models, Animal; D009419:Nerve Tissue Proteins / Q000037:antagonists & inhibitors*; D018696:Neuroprotective Agents / Q000494:pharmacology / Q000627:therapeutic use*; D010456:Peptides, Cyclic / Q000494:pharmacology / Q000627:therapeutic use*; D010766:Phosphorylation; D011499:Protein Processing, Post-Translational / Q000187:drug effects; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism; D040301:Vascular Endothelial Growth Factor Receptor-2 / Q000378:metabolism
D039302:Integrin alphaVbeta3; D009419:Nerve Tissue Proteins; D018696:Neuroprotective Agents; D010456:Peptides, Cyclic; D042461:Vascular Endothelial Growth Factor A; C092113:cyclo(arginyl-glycyl-aspartyl-phenylalanyl-valyl); C467498:vascular endothelial growth factor A, rat; D005070:Evans Blue; D005340:Fibrinogen; D040301:Vascular Endothelial Growth Factor Receptor-2; D051417:Focal Adhesion Kinase 1; C496052:Ptk2 protein, rat