This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Kupatt, C. Articles by Boekstegers, P. Search for Related Content PubMed PubMed Citation Articles by Kupatt, C. Articles by Boekstegers, P. Related Collections Animal models of human disease Ischemic biology - basic studies

(Circulation. 2005;112:I-117 – I-122.)
© 2005 American Heart Association, Inc.

Cell Transplantation and Tissue Engineering

Retroinfusion of Embryonic Endothelial Progenitor Cells Attenuates Ischemia-Reperfusion Injury in Pigs

Role of Phosphatidylinositol 3-Kinase/AKT Kinase

Christian Kupatt, MD; Rabea Hinkel, DVM; Mathias Lamparter, MSc; Marie-Luise von Brühl, DVM; Tilman Pohl, MD; Jan Horstkotte, MD; Heike Beck, DVM; Susanne Müller; Sebastian Delker; Franz-Josef Gildehaus, PhD; Hildegard Büning, PhD; Antonis K. Hatzopoulos, PhD; Peter Boekstegers, MD

From Internal Medicine I (C.K., R.H., M.-L.vB., T.P., J.H., S.M., S.D., P.B.), Klinikum Grosshadern, Munich, Germany; GSF Research Center for Environment and Health (M.L., H.B., A.K.H.), Institute for Clinical Molecular Biology and Tumor Genetics, Munich, and Division of Cardiovascular Medicine (M.L., A.K.H.), Vanderbilt University Medical Center, Nashville, Tenn; Department of Nuclear Medicine (F.-J.G.), Klinikum Grosshadern, Munich, Germany; and Gene Center (H.B.), Ludwig-Maximilians-University, 81377 Munich, Germany.

Correspondence to Christian Kupatt, MD, Internal Medicine I, Klinikum Grosshadern, Marchioninistr. 15, 81377 Munich, Germany. E-mail christian.kupatt{at}med.uni-muenchen.de

Background— Adult endothelial progenitor cells (EPCs) reduce myocardial infarct size and improve postischemic myocardial function. We have recently shown that clonal embryonic EPCs (eEPCs), derived from 7.5-day-old mice, home specifically to hypoxic areas in tumor metastasis mouse models but spare normal organs and do not form carcinomas. Here, we assessed the potential of eEPCs to limit organ dysfunction after ischemia and reperfusion in a preclinical pig model.

Methods and Results— Pigs were subjected to ischemia (60-minute left anterior descending [LAD] artery occlusion) and reperfusion (7 days). At the end of ischemia, we applied medium with or without 5x10⁶ eEPCs by either pressure-regulated retroinfusion or intravenous transfusion. One hour after reperfusion, ⁹⁹Tc-labeled eEPCs engrafted to a 6-fold higher extent in the ischemic myocardium after retroinfusion than after intravenous application. Regional myocardial function (subendocardial segment shortening [SES] at 150/min, given in percent of nonischemic circumflex region) and infarct size (TTC viability and Methylene-blue exclusion) were determined 24 hours and 7 days later. Compared with medium-treated animals, retroinfusion of eEPCs decreased infarct size (35±4% versus 51±6%) and improved regional myocardial reserve of the apical LAD region (SES 31±4% versus 6±8%), whereas intravenous application displayed a less pronounced effect (infarct size 44±4%; SES 12±3%). Retroinfusion of an equal amount of neonatal coronary endothelial cells (rat) did not affect infarct size (49±5%) nor regional myocardial reserve (16±7%). The eEPC-dependent effect was detected at 24 hours of reperfusion (infarct size 34±7% versus 58±6%) and was sensitive to Wortmannin coapplication (50±5%).

Conclusion— Our findings show that eEPCs reduce ischemia-reperfusion injury in a preclinical pig model. The rapid effect (as early as 24 hours) indicates a role for enzyme-mediated cardioprotection, which involves, at least in part, the phosphatidylinositol 3-kinase/AKT pathway.

Key Words: angiogenesis • endothelium-derived factors • ischemia • infarction