冠心病心梗属中医胸痹之真心痛，病机为瘀血停积、秽浊内阻。前期应用既具活血又有辟秽浊作用之降香，取得较好临床疗效；基础研究显示降香有促血管新生作用。尽管治疗性血管新生已成为治疗缺血性心脏病的新策略，但促血管新生西药如血管内皮生子因子（VEGF）有潜在促肿瘤增殖效应，限制了其临床应用。我们前期研究发现降香提取物B3有促血管新生效应却对肿瘤增殖无作用，提示其相对促血管新生因子的优势。然而，B3促血管新生机制不明。鉴于VEGF/VEGF受体及下游信号通路（PI3K-AKT和Ras-Raf-MEK-ERK）在血管新生中的重要作用，我们设想降香提取物B3可能通过激活VEGF/VEGF受体及其下游信号通路而促血管新生。根据这一设想，本项目拟采用冠脉结扎致大鼠心梗模型和缺氧诱导内皮细胞损伤模型，系统考察B3的促血管新生作用，并深入研究其作用机制，以期为临床应用降香治疗缺血性心脏病提供实验依据和理论支持。

Angina pectoris is regarded as blood arthralgia in Traditional Chinese Medicine, and its pathogenesis was blood stasis and dirty muddy. Traditional Chinese herb Dalbergia odorifera is clinically used to promote blood circulation and remove muddy in China, and experimental studies also show its angiogenic effects. Although therapeutic angiogenesis has emerged as a promising investigational strategy for the treatment of patients with ischemic heart disease, the pro-angiogenic factors such as vascular endothelial growth factor (VEGF), have a potential role in promoting tumor neovascularization, which limits their clinical application. Our previous study found that the extract B3 of Dalbergia odorifera has angiogenic effect without promoting tumor growth, suggesting its advantage over pro-angiogenic factors. However, the underlying molecular mechanisms of angiogenic effects of B3 are still unknown. Given the important roles of VEGF signal transduction in angiogenesis, we hypothesize that B3 may promote angiogenesis by activating VEGF/VEGF receptor downstream signaling pathways, such as PI3K-AKT and Ras-Raf-MEK-ERK. To test the hypothesis, rat myocardial infarction model (in vivo) and endothelial cells damage model induced with hypoxia (in vitro) were used to investigate the promoting effects of B3 on coronary angiogenesis and neovascularization, and endothelial cell viability and apoptosis. Moreover, VEGF/VEGFR signal transduction including PI3K-AKT and Ras-Raf-MEK-ERK were also studied. Finally, specific inhibitors will be used to elucidate the molecular mechanisms of B3s angiogenic effects. This study may provide experimental and theoretical supports for Dalbergia odorifera application to treat ischemic heart diseases.

背景：心肌缺血非常普遍，但是西药促血管新生尚未用于临床。然而，促血管新生中药有一定的应用前景，但是机制还不清楚。目的：豆科植物降香檀Dalbergia odorifera T. Chen 树干和根的干燥心材在中医临床上常被用于各种缺血性疾病的治疗。本研究在前期基础上采用多种化学分离分析手段，利用Tg（fli-1a：EGFP）y1转基因斑马鱼及人脐静脉内皮细胞模型，对降香促血管新生的有效部位（B3、B3-5及B3-6）进行体内外药理学研究。方法：在Tg（fli-1a：EGFP）y1转基因斑马鱼体内研究中，本研究观察降香不同部位提取物对正常斑马鱼肠下血管出芽新生的效果；通过q-PCR实验评价降香提取物对VRI诱导的转基因斑马鱼ISVs区域血管损伤的治疗作用；体外研究中，本研究通过MTT实验及划痕实验测试降香提取物诱导人脐静脉细胞增殖、迁移的能力，以及对VRI诱导的内皮细胞损伤是否有具有修复作用；又通过蛋白芯片筛选出降香提取物促血管新生相关的信号通路，利用Western Blot加以验证并完善信号通路的研究。结果：体内试验中，降香提取物B3、B3-5及B3-6在不同安全浓度下均能显著地促进正常转基因斑马鱼肠下血管的新生出芽；能明显的修复VRI诱导的转基因斑马鱼节间血管损伤。q-PCR实验中VRI模型组可使VEGF相关受体mRNA表达下降，而降香提取物B3、B3-5及B3-6能显著并剂量依赖地提高这些受体的表达；体外实验中，降香提取物B3、B3-6在安全浓度下能显著促进内皮细胞的增殖，B3-6能有效促进内皮细胞迁移，并具一定的剂量依赖性。同时，B3-6还能改善VRI诱导的内皮细胞损伤。此外，Akt信号通路蛋白芯片实验及Western Blot实验证明了降香提取物B3-6对调控增殖、迁移及存活的PI3K/MAPK信号通路的激活作用。结论：降香提取物B3、B3-5及B3-6在转基因斑马鱼模型及人脐静脉内皮细胞模型上均有良好的促血管新生和修复血管损伤的效果。其中B3-6效果较强，其机制可能与其调控血管新生相关受体mRNA表达水平、激活PI3K/MAPK等信号通路有关。科学意义：为心梗和缺血性心肌病提供了一种有效的治疗方法和途径。