抑制新生血管多肽ZY9优化及作用机制研究

Our previous studies have selected a novel 21-amino acid peptide from human placenta growth factor, named ZY1. ZY1 inhibited VEGF-induced choroid-retina endothelial cell proliferation, migration and tube formation in vitro. It also inhibited ocular neovascularization when applied to the corneal micropocket angiogenesis assays and OIR assays in mice. Recently, we optimized ZY1 peptide by conformation analysis, and found a smaller 9-amino acid peptide, named ZY9. ZY9 peptide could inhibit angiogenesis as effective as ZY1, but the molecular weight of ZY9 is smaller than ZY1. The amino acid composition of ZY9 is more reasonable. Based on these previous researches, this study will further optimize ZY9 peptide with chemistry, molecular biology, and computer aided technology, in order to increase the affinity to its receptor, and enhance its anti-angiogenic activities. The anti-angiogenic effect and safety study of optimized-ZY peptide will be verified by multiple in vitro and in vivo studies. The molecular mechanism of optimized-ZY peptide in inhibiting ocular neovascularization will be further elucidated. Small peptides, owing to their potential efficacy, sufficient penetration capability, less toxicity, and controllable production, are ideal alternatives for ocular application. This study will develop a new peptide with highly activity in inhibiting ocular neovascular-ization, and clear molecular mechanism. Our research will provide great foundation for the transformation of these anti-angiogenic peptides into clinically applicable drugs in treating ocular neovascular diseases.

课题组前期从胎盘生长因子中筛选出新型多肽ZY1，该多肽在体外能够抑制VEGF诱导的血管内皮细胞增殖、迁移及管腔形成，在体内能够有效抑制小鼠角膜及视网膜新生血管。近来，课题组通过分子结构分析对ZY1多肽进行了初步优化，在保持其活性不变的情况下，获得了分子量更小、结构稳定的多肽ZY9。本课题将在上述研究基础上，进一步运用化学、分子生物学及计算机模拟方法对ZY9多肽进行再优化，增加其与受体的亲和力，进而增强生物学活性；通过多种体内外细胞及新生血管动物模型证实优化后ZY多肽（optimized-ZY）具有更好的抑制新生血管效果及其安全性；探讨optimized-ZY多肽抑制眼部新生血管的作用机制。通过本项目研究将有望找到一种有效抑制新生血管、制备简单、成本较低的潜在小分子多肽类抗新生血管药物，为其向临床转化奠定基础。

本课题组前期筛选及验证具有抑制新生血管作用的多肽ZY9，在此基础上探究ZY9多肽在细胞表面的受体，根据其与受体的相互作用，应用生物信息学计算机模拟技术对ZY9多肽进行优化，得到与受体亲和力更佳，生物活性更强的优化多肽optimized-ZY9；通过体外细胞增殖、迁移、管腔形成等试验，体内鸡胚尿囊膜模型、高氧诱导小鼠视网膜新生血管等模型，探讨optimized-ZY9对体内外新生血管的作用；在证实优化多肽可有效抑制新生血管的基础上，通过组织形态学及功能学方法验证其眼部安全性；对VEGF相关信号通路检测阐明optimized-ZY9多肽抑制眼部新生血管的作用机制。旨在从有效性、安全性及细胞分子机理等多方面阐释该优化多肽抑制新生血管的效果及机制。研究证实optimized-ZY9能够安全有效抑制眼部新生血管，并显著降低VEGFR-1，ERK及AKT关键信号分子的表达。本课题成果可望发现一种更加适于眼组织的安全有效的新型新生血管抑制剂，并为其向临床成果转化奠定基础。