Department of Radiology, Xijing Hospital of the Fourth Military Medical University, Xi'an, Shaanxi 710032, P.R. China.
Int J Mol Med. 2014 Jan;33(1):171-7. doi: 10.3892/ijmm.2013.1558. Epub 2013 Nov 19.
PR39 is an angiogenic masterswitch protein, belonging to the second generation of angiogenic growth factors. However, the role of recombinant adeno-associated virus (AAV) carrying the PR39 fusion gene (AAV-PR39) in acute myocardial infarction remains unclear. Therefore, in this study, we investigated the role of AAV-PR39 in an experimental animal model of acute myocardial infarction. The PR39 gene was fused with the transmembrane peptide, TAT, 6xHis‑tag and NT4 signal sequences. AAV-PR39 was then obtained by calcium phosphate co-precipitation. A total of 18 healthy Chinese mini pigs were randomly divided into an experimental groups (the AAV-PR39-treated group) and a control group [phosphated-buffered saline (PBS)-treated group]. Following the induction of myocardial infarction, enhanced 3.0T MR imaging was performed to observe the changes in myocardial signal intensity at 0 h, 1, 2 and 3 weeks. The expression of hypoxia-inducible factor‑1α (HIF-1α) in the myocardial tissues was determined by SABC immunohistochemistry. In addition, in vitro experiments using CRL-1730 endothelial cells transfected with AAV vector containing NT4-TAT-His-PR39 revealed that the AAV-PR39-treated group had a significantly higher expression of HIF-1α compared with the control group. Moreover, PR39 regulated the HIF-1α-induced expression of angiogenic growth factors. Under hypoxic conditions, the anti-apoptotic effects in the AAV-PR39 group were more pronounced than those observed in the control (PBS-treated) group. In vivo, the enforced expression of recombinant PR39 elevated the level of HIF-1α under hypoxic conditions and decreased the size of the infarcted areas by upregulating the expression of HIF-1α in the areas surrounding the infarct area. Taken together, our data demonstrate that the recombinant AAV-PR39-mediated HIF-1α expression attenuates myocardial infarction, indicating that AAV-PR39 may serve as a novel therapeutic agent for the treatment of myocardial infarction.
PR39 是一种血管生成主控开关蛋白，属于第二代血管生成生长因子。然而，携带 PR39 融合基因的重组腺相关病毒（AAV）（AAV-PR39）在急性心肌梗死中的作用尚不清楚。因此，在本研究中，我们研究了 AAV-PR39 在急性心肌梗死实验动物模型中的作用。将 PR39 基因与跨膜肽、TAT、6xHis 标签和 NT4 信号序列融合。然后通过磷酸钙共沉淀获得 AAV-PR39。共纳入 18 只健康的中国小型猪，随机分为实验组（AAV-PR39 治疗组）和对照组[磷酸盐缓冲液（PBS）治疗组]。在诱导心肌梗死后，在 0 h、1 周、2 周和 3 周时使用增强 3.0T MR 成像观察心肌信号强度的变化。通过 SABC 免疫组化法测定心肌组织中缺氧诱导因子-1α（HIF-1α）的表达。此外，用转染含有 NT4-TAT-His-PR39 的 AAV 载体的 CRL-1730 内皮细胞进行体外实验，结果表明 AAV-PR39 治疗组的 HIF-1α 表达明显高于对照组。此外，PR39 调节 HIF-1α 诱导的血管生成生长因子的表达。在缺氧条件下，AAV-PR39 组的抗凋亡作用比对照组（PBS 治疗组）更为明显（P＜0.05）。在体内，重组 PR39 的强制表达在缺氧条件下升高了 HIF-1α 的水平，并通过上调梗死区域周围区域的 HIF-1α 表达减少了梗死区域的大小。综上所述，我们的数据表明，重组 AAV-PR39 介导的 HIF-1α 表达减轻了心肌梗死，表明 AAV-PR39 可能成为治疗心肌梗死的一种新型治疗剂。
