基于阳离子多肽构建的载体及其在小分子药物和基因运输中的应用

发布时间：2018-03-08 14:34

本文选题：穿膜肽　切入点：抗菌肽　出处：《兰州大学》2017年硕士论文　论文类型：学位论文

【摘要】：肿瘤是严重危害人类生命和生活的重大疾病之一。化疗是目前治疗或减缓肿瘤生长的主要方法。然而大多数传统的小分子抗肿瘤药物因选择性差、毒副作用强、易引发多药耐药性等缺点严重影响了临床疗效。另一方面,大分子药物(例如,蛋白质或基因)相比目前的小分子抗癌药物由于其强效和特异性而引起人们巨大的兴趣。但是,这些大分子药物的细胞内递送却是一个巨大的挑战。发展具有高选择性、新的作用机制和作用靶点、不易引起多药耐药性的新型抗肿瘤药物已成为迫切需要解决的问题。在这方面,药物递送系统(DDS)一直在探索之中,以解决这些药物治疗所面临的困境。在过去几十年中,新开发的许多生物材料由于其在各种领域具有的潜在用途而引起了人们极大的兴趣,包括在医学,生物学,化学和组织工程等领域。迄今为止,这些生物材料已经在癌症治疗领域产生了显著的影响。在抗癌药物递送中,以穿膜肽(CPPs)为代表的阳离子多肽因它们独特的作用机制以及在肿瘤治疗中表现出的巨大前景而受到广泛关注。本论文分别以穿膜肽TAT和抗菌肽CAMEL为模板,通过对其结构进行再设计,使其能够更加高效运输小分子药物CPT或基因治疗药物,并对它们在肿瘤治疗中的应用进行了尝试与探索。1.TAT-CPT共轭物的抗肿瘤活性研究。我们将穿膜肽TAT与传统抗肿瘤药物CPT缀合。一方面,与TAT结合后,CPT药物的水溶性得到提升,经修饰后的CPT在体内的稳定性增强;同时,CPT又能增加TAT的疏水性,可以增强TAT的穿膜活性,进而将更多CPT分子携带进入肿瘤细胞中。针对TAT中引入CPT的适合位点,以及连接键筛选,我们对TAT和CPT进行了不同方式的连接,如CPT与TAT不同位点的连接,以及变换不同的连接键(二硫键/酯键),在此基础上设计合成了一系列TAT共轭类似物,并对它们的穿膜活性和抗肿瘤效果进行了检测与评估,以探索TAT-CPT缀合物的最佳构建模式。实验结果表明,共轭物整体疏水性增强后,促使TAT携带较多CPT内化进入肿瘤细胞,药物浓度得到提升,与CPT相比抗肿瘤效果增强;而在连接子的酶解稳定性方面,酯键与二硫键相比更加稳定。2.SP7作为抗肿瘤基因药物递送载体的研究。CAMEL是一种同时具有抗革兰氏阳性和阴性细菌活性的杂合抗菌肽。研究证明CAMEL可以穿透细胞并作用于线粒体导致细胞死亡,表明CAMEL具有作为药物递送载体的潜能。SP,是一种含有11个氨基酸残基的神经肽,能够通过与速激肽-1(NK-1)受体特异性结合而迅速内化。而NK1受体在许多类型的癌症中高表达,比如乳腺癌、星形细胞瘤、胶质母细胞瘤等。因此,在本文中,我们将CAMEL与SP连接在一起而构建一种具有肿瘤靶向的嵌合肽SP7。并通过在其N末端连接十八烷酸,以期构建高效的基因运输载体。实验结果表明:CAMEL与SP7偶联十八烷酸后都能增强质粒的胞内输送能力;与CAMEL相比,18-SP7的穿膜活性对NK1受体高表达的细胞表现出选择性;18-SP7能够选择性的将基因运输到高表达NK1受体的细胞内。
[Abstract]:Tumor is one of the most serious diseases endangering human life and life. Chemotherapy is the main method for the treatment or to slow tumor growth. However, most of the traditional small molecule anti-tumor drugs due to poor selectivity, strong side effects, easy to cause the disadvantages of multi drug resistance has seriously affected the clinical effect. On the other hand, macromolecular drugs (for example, proteins or genes) compared to small molecular current anticancer drugs due to its potent and specific and attracted great interest. However, these large molecules for intracellular delivery is a huge challenge. The development of high selectivity, and the mechanism of the new target, is not easy to cause the new anti-tumor drug multidrug resistance has become an urgent problem to be solved. In this regard, drug delivery system (DDS) has been explored, in order to solve these difficulties facing the drug treatment in the past few. In ten years, many new biological materials developed a great interest due to its potential applications in various fields, including in medicine, biology, chemistry and tissue engineering and other fields. So far, the biological material has produced a significant impact in the field of cancer. Anticancer drug delivery, to membrane penetrating peptide (CPPs) cationic peptides represented has attracted widely attention due to their unique mechanism of action and show great prospects in the treatment of cancer. This study was based on a membrane penetrating peptide TAT and peptide CAMEL as template, and then through the design of its structure, to make it more efficient transportation or CPT gene therapy of small molecule drugs, and their application in tumor therapy of anti tumor activity study and exploration of.1.TAT-CPT conjugate. We will membrane penetrating peptide TAT and traditional anti-cancer drugs with CPT . on the one hand, when combined with TAT, CPT improves the water solubility of drugs, the modified CPT enhanced in vivo stability; at the same time, CPT can increase the hydrophobicity of TAT, TAT can enhance the penetrating activity, then more CPT molecules carry into tumor cells. According to the introduction of CPT TAT the suitable site, and linkage screening, we performed different ways of connecting TAT and CPT, such as CPT and TAT connection of different sites, and the transformation of different connectors (two disulfide / ester bond), based on the design and synthesis of a series of TAT conjugated analogues, and the penetrating activity and their anti-tumor effects were detected and evaluated, in order to build the best model to explore TAT-CPT conjugates. The experimental results show that the overall hydrophobic conjugate enhanced, prompting TAT to carry more CPT internalization into tumor cells, the drug concentration increased, compared with CPT anti tumor effect Guo Zengqiang; and in the linker enzyme stability, compared with two disulfide ester bond of.CAMEL.2.SP7 as a more stable anti-tumor gene drug delivery vector is a kind of both anti gram positive and negative bacteria activity of hybrid antimicrobial peptides. The study shows that CAMEL can penetrate the cell and the role of the mitochondria leads to cell death., show that CAMEL has potential as a drug delivery carrier is.SP, containing a 11 amino acid neuropeptide, can with tachykinin -1 receptor (NK-1) specific binding and internalization of NK1 receptor and cancer rapidly. In many types of high expression, such as breast cancer, astrocytoma, glioblastoma blastomas. Therefore, in this paper, we combine CAMEL and SP together to construct a chimeric peptide SP7. with tumor targeting and in its N terminal connected by eighteen alkyl acid, in order to build an efficient gene. Transport carrier. The experimental results show that the coupling of CAMEL and SP7 eighteen alkyl acid can enhance plasmid intracellular delivery capacity; compared with CAMEL, 18-SP7 transmembrane activity on NK1 receptor expression in the cells exhibit selectivity; 18-SP7 can selectively transport genes to high expression of NK1 receptor in the cell.

【学位授予单位】：兰州大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：R730.5

【相似文献】