Influence of HMGB1 and MSCs transplantation on rat cardiac angiogenesis with acute myocardial infarction

ABSTRACT

To observe whether HMGB1could enhance the paracrine effect of MSCs when the Mesenchymal stem cells [Mesenchymal stem cells, MSCs] are pre-proccessed by High Mobility Group Box-1 [High Mobility Group Box-1, HMGB1]. And to observe whether it can further increase the quantity of local angiogenesis in myocardial infarcts on the rat model with acute myocardial infarction, HMGB1 was combined with MSCs transplantation. MSCs in rats were cultivated with adherence and centrifugation method. Receptors of TLR4and RAGE in HMGB1 were tested. The MSCs were interfered by HMGB1 with different concentration gradient respectively, then the expression of VEGF was tested with ELISA method. SD male rats were divided into four groups the model group, the MSCs transplantation group, the HMGB1 injection group, the HMGB1 injection plus MSCs transplantation group [n = 24], preparing rat model with acute myocardial infarction. The serum VEGF concentration levels were detected on the 3[rd] day, 7th and 28th day with ELISA method. On the 28th day after post operation the density of angiogenesis in infarction area was detected by immunohistochemal. [1] MSCs owned the expression of TLR4 and RAGE. [2] the secretion of VEGF increased significantly after the intervention of HMGB1 with concentration of 12.5 ng/mL, 25 ng/mL, 50 ng/mL, 100 ng/mL and 200ng/ml on MSCs compared with the control group. While the concentration was 400ng/ml or 800ng/ml, the secretion of VEGF decreased compared with the control group [P < 0.05]. [3] detection of the serum VEGF on the 3[rd] or7th day after post operation was arranged The results showed that HMGB1 injection plus MSCs transplantation group > MSCs transplantation group >HMGB1 injection group >model group [P < 0.05]. [4] the quantity of CD31 stained angiogenesis in HMGB1 injection plus MSCs transplantation group increased obviously. Combining MSCs transplantation, contributed to new angiogenesis of rats with acute myocardial infarction in myocardial infarction area and its near area in rats with acute myocardial infarction