Intravenous Or Intracoronary Transplantation Of Umbilical Cord Mesenchymal Stem Cells Into Pigs With Acute Myocardial Infarction

Objective:To investigate the effects of umbilical cord mesenchymal stem cells transplantation through vein or coronary on cardiac function, myocardial infarct size, capillary number of acute myocardial infarction (AMI) pigs.Methods:The ainimal study was conducted at Animal Laboratory of TED A international Cardiovascular Hospital from January2011to June2012. AMI was performed by continuous block of anterior blood flow with target diameter of balloon in left ant erior desending coronary artery.23Pigs after myocardial infarction were randomized into three groups:coronary artery group (8Pigs), intravenous (IV) group (8Pigs) and a control group (7Pigs). The stem cells were transplanted via coronary artery and vei n two weeks after acute myocardial infarction in the transplantation group and the saline were jnjected via vein in the control group. LVEDV, LVESV, LVEF and FS were measured two weeks after the LAD ligation and six weeks after the MNCs transplantation, respectively. The myocardial perfusion imaging was examined before tanspla-ntation,6weeks after infusion, to calculate the farct area and the quality of infarct region. Six weeks after infusion, pigs were killed by giving injection of potassium chloride. Capillary number was counted by vWF immunohistochemical staining, and the electron microscopy was used to observe MSCs differentiation.Results:1. Compared with control group, the cardiac function was significantly improved left ventricular end-diastolic volume (LVEDV) decreased, left ventricular systolic volume (LVESV) decreased, left ventricular ejection fraction (LVEF) and fractional shortening (FS) increased in coronary artery transplantation and vein transplantation [coronary artery group:56.86±7.62mm,16.25±6.45mm,71.25±8.94%,39.52±6.85%; intravenous group:59.38±5.55mm,17.63±6.14mm,69.38±6.93%,38.25±6.69%; control group:70.57±8.50mm,25.57±7.55mm,59.71±7.18%,31.29±5.19%;(P<0.05)]. There was no significant difference between coronary artery transplantation group and vein transplantation group (P>0.05).2. Compared with control group, the farct area and the quality of infarct region were smaller in coronary artery transplantation and vein transplantation [coronary artery group:15.13±2.99%,16.13±2.99%; intravenous group:13.13±3.23%,15.00±3.07%; control group:21.43±5.88%,22.86±6.49%;(P<0.05)]. There was no significant difference between coronary artery transplantation group and vein transplantation group (P>0.05).3. Compared with control group, the number of capillaries was increased in coronary artery transplantation and vein transplantation [coronary artery group:14.71±2.99; intravenous group:13.58±2.65; control group:10.24±1.71;(P<0.05)]. There was no significant difference between coronary artery transplantation group and vein transplantation group (P>0.05).4. Umbilical cord-MSCs were mainly located within per infarct and infarct area six weeks after the MSCs transplantation. Vascular endothelial cells and myocardium like cells differentiated by stem cells can be found in the infracted cardiac tissues using electron microscopy.Conclusion:Intravenous or intra-coronary artery transplantations of umbilical cord mesenchymal stem cells can effectively improve cadiac function, increase capillary density and decrease myocardial infarct size of AMI pigs. But there was no significant difference between two transplantation ways.