人脐带间充质干细胞移植对AMI大鼠心肌血管内皮生长因子和IL-6的影响

Effects of human umbilical cord mesenchymal stem cells on vascular endothelial growth factor and IL-6 expression in tissue of AMI rats

目的探讨人脐带间充质干细胞（UC-MSCs）移植治疗对急性心肌梗死（AMI）大鼠心肌组织血管内皮生长因子（VEGF）及白细胞介素-6（IL-6）的影响。方法获取人UC-MSCs并培养至第4代用于实验。将60只雄性SD大鼠按随机数字表法分为假手术组、AMI模型组、UC-MSCs治疗组，每组20只。以结扎冠状动脉（冠脉）前降支制备AMI动物模型；假手术组于冠脉前降支下穿线、不进行结扎。UC-MSCs治疗组于制模成功后24 h经尾静脉输注UC-MSCs 2×106个。于制模后7 d处死动物，取结扎线以下心肌组织及冠脉，用反转录-聚合酶链反应（RT-PCR）和蛋白质免疫印迹试验（Western Blot）分别检测心肌组织IL-6的mRNA和蛋白表达；用免疫组化法观察冠脉VEGF阳性表达。结果AMI模型组心肌组织IL-6 mRNA和蛋白表达均明显高于假手术组（灰度值：0.732±0.131比0.321±0.080，0.678±0.191比0.286±0.061，均P〈0.05）；UC-MSCs治疗组心肌组织IL-6 mRNA和蛋白表达明显低于AMI模型组（灰度值：0.300±0.104比0.732±0.131，0.312±0.101比0.678±0.191，均P〈0.05）。光镜下观察显示，AMI模型组冠脉VEGF阳性细胞较假手术组明显增多（个/HP：21.1±2.2比7.6±1.3，P〈0.05），且UC-MSCs治疗组VEGF阳性细胞较AMI模型组进一步增多（个/HP：41.5±3.1比21.1±2.2，P〈0.05）。结论人UC-MSCs移植治疗可有效提高AMI大鼠冠脉内VEGF表达，以改善损伤区域血管重建，并通过降低IL-6表达有效抑制炎症进展。

To investigate the effects of human umbilical cord mesenchymal stem cells （UC-MSCs） on vascular endothelial growth factor （VEGF） and interleukin-6 （IL-6） expression in acute myocardium infarction （AMI） rats.MethodsThe human UC-MSCs were cultured to the 4th generation for experiment. Sixty male Sprague-Dawley （SD） rats were randomly divided into sham group, AMI model group and UC-MSCs group, with 20 in each group. AMI animal model was produced by ligation of anterior descending coronary artery; in the sham group, the threading vein was gone below without ligation. In UC-MSCs group 2×106 UC-MSCs were infused through the caudal vein at 24 hours after successful model production. The animals were sacrificed after 7 days; the myocardial tissue and coronary artery below the ligation line were harvested. The mRNA and protein expressions of IL-6 in myocardium were detected by reverse transcription-polymerase chain reaction （RT-PCR） and Western Blot. The positive expression of VEGF in coronary artery was observed by immunohistochemisty.ResultsCompared with the sham group, the mRNA and protein expressions of IL-6 in myocardium in AMI model group were increased significantly （gray value： 0.732±0.131 vs. 0.321±0.080, 0.678±0.191 vs. 0.286±0.061, both P 〈 0.05）. Compared with the AMI model group, the mRNA and protein expressions of IL-6 in myocardium in UC-MSCs group were decreased significantly （gray value： 0.300±0.104 vs. 0.732±0.131, 0.312±0.101 vs. 0.678±0.191, both P 〈 0.05）. Observation under light microscope, the VEGF positive cells in AMI model group was increased significantly compared with the sham group （cells/HP： 21.1±2.2 vs. 7.6±1.3, P 〈 0.05）, the VEGF positive cells in UC-MSCs group were increased significantly compared with the AMI model group （cells/HP： 41.5±3.1 vs. 21.1±2.2, P 〈 0.05）.ConclusionHuman UC-MSCs could promote angiogenesis by the improvement of VEGF in coronary artery and inhibit the inflammation by the reduction of IL-6 in rats with AMI.