Department of Cardiology, the Affiliated Union Hospital, Fujian Medical University, 29 Xin-Quan Road, Fuzhou, 350001, PR China.
J Mol Cell Cardiol. 2011 Nov;51(5):839-47. doi: 10.1016/j.yjmcc.2011.06.013. Epub 2011 Jun 29.
Ischemic postconditioning (IPC) is cardioprotective against ischemia-reperfusion injury which impairs the myocardial micro-environment and reduces the survival of transplanted cells. We tested the hypothesis that IPC may improve the survival of transplanted cells and enhance their therapeutic effects. In this study, bone marrow-derived mesenchymal stem cells (BMSCs) from Sprague-Dawley rats were infected with lentivirus carrying green fluorescent protein (GFP) gene. The left main coronary arteries of rats were occluded for a 30-min ischemia, followed by a 72 h or 28 d reperfusion. IPC was induced by 3 cycles of 10s reperfusion and 10s ischemia before sustained reperfusion. GFP-BMSCs were intramyocardially injected at 2h reperfusion. At 70 h after transplantation, IPC treatment increased the level of interleukin-10, B-cell leukemia-lymphoma-2 (BCL-2), and vascular endothelial and basic fibroblast growth factor (VEGF and bFGF), and decreased the level of tumor necrosis factor-α, interleukin-1β and BCL-2-associated X protein by ELISA or PCR or western blotting. The BMSCs therapy with IPC produced more surviving GFP-positive cells than the BMSCs therapy alone by fluorescent staining [at 70 h, (90 ± 14)/mm(2) vs. (61 ± 12)/mm(2), and at 28 days, (55 ± 14)/mm(2) vs. (26 ± 8)/mm(2), P<0.01, respectively]. At 28 days, it, when compared with the Control, IPC treatment, and BMSCs therapy, demonstrated higher left ventricular ejection fraction by echocardiography (62%± 8%, 69%± 6%, and 75%± 4% vs. 82%± 4%, P<0.05, respectively), higher expression of VEGF and bFGF by western blotting and PCR, less myocardial fibrosis by Masson's trichrome staining, and higher capillary density by immunohistochemistry. These results suggest that ischemic postconditioning promotes the survival of transplanted cells and enhances their repair of infarcted myocardium through paracrine mechanisms.
缺血后处理（IPC）可对抗缺血再灌注损伤，损伤心肌微环境，降低移植细胞的存活率。我们验证了假设，即 IPC 可能改善移植细胞的存活率，并增强其治疗效果。在这项研究中，来自 Sprague-Dawley 大鼠的骨髓间充质干细胞（BMSC）被感染携带绿色荧光蛋白（GFP）基因的慢病毒。大鼠的左主干冠状动脉闭塞 30 分钟，然后再灌注 72 小时或 28 天。在持续再灌注前，通过 3 个周期的 10s 再灌注和 10s 缺血来诱导 IPC。在再灌注 2 小时时进行 GFP-BMSC 心肌内注射。移植后 70 小时，IPC 处理通过 ELISA、PCR 或 Western blot 增加了白细胞介素-10、B 细胞淋巴瘤-2（BCL-2）、血管内皮和碱性成纤维细胞生长因子（VEGF 和 bFGF）的水平，降低了肿瘤坏死因子-α、白细胞介素-1β 和 BCL-2 相关 X 蛋白的水平。通过荧光染色，IPC 处理的 BMSC 治疗比单独 BMSC 治疗产生更多存活的 GFP 阳性细胞[在 70 小时时，（90±14）/mm(2) 比（61±12）/mm(2)，在 28 天时，（55±14）/mm(2) 比（26±8）/mm(2），P<0.01]。在 28 天，与对照组、IPC 处理组和 BMSC 治疗组相比，通过超声心动图显示左心室射血分数更高（62%±8%、69%±6%和 75%±4%比 82%±4%，P<0.05），Western blot 和 PCR 显示 VEGF 和 bFGF 表达更高，Masson 三色染色显示心肌纤维化减少，免疫组织化学显示毛细血管密度更高。这些结果表明，缺血后处理通过旁分泌机制促进移植细胞的存活，并增强其对梗死心肌的修复。
