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Design of the nanointerface for detection, recovery, and regeneration of abnormal proteins

用于异常蛋白质检测、回收和再生的纳米界面设计

基本信息

批准号：
14380412
负责人：
FUJIMOTO Keiji
金额：
$ 7.1万
依托单位：
Keio University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
2002
资助国家：
日本
起止时间：
2002 至 2004
项目状态：
已结题

项目摘要

Polymeric nanoparicles have been paid to attention as a drug carrier. It is required that carriers are inert and non-toxic and are not accumulated or are degradable in the body. Therefore we selected poly-L-lysine (PLL) that is degradable polypeptide for a backbone of a nanoparticle. Because PLL exhibits structural changes among random, helix, and β-sheet by pH and temperature, we expect the stimuli-sensitive release of drugs from nanoparticles.PLL was allowed to react with poly (ethylene glycol) (PEG) to improve the dispersion-stability and to prolong the lifetime in blood (mPEG-PLL polymer). Then, mPEG-PLL polymer was coupled with phosphatidic acid (PA) that acts as a hydrophobic site (mPEG-PLL-PA nanoparticle). The obtained polymers spontaneously aggregated into a nanoparticulate shape by the hydrophobic association among PA moieties. Whilst mPEG-PLL polymers were assembled to nanoparticles upon the formation of β-sheet structure in high pHs and high temperatures (mPEG-PLL nanoparticle). Both nanoparticles were 10-80nm in size and possessed the positive change. FITC-labeled nanoparticles were internalized into A431 cells. Adriamycin (ADR) that is an anticancer drug was incorporated into mPEG-PLL-PA nanoparticle more than mPEG-PLL nanoparticle because of PA's great hydrophobicity. However, drug release showed an opposite tendency. In pH4, release rate of ADR from mPEG-PLL nanoparticles was faster than that from mPEG-PLL-PA nanoparticles. Thereby survival rate of A431 cells decreased when they were treated with ADR-loaded mPEG-PLL nanoparticles.We applied β-sheet association of the mPEG-PLL polymer to inhibition of protein aggregation. PLL tends to aggregate through β-sheet association by raising pH and temperature. This aggregation could be inhibited by adding the mPEG-PLL polymer. This suggests that the mPEG-PLL polymer is capable of inhibiting aggregation of abnormal proteins that cause conformational diseases.

聚合物纳米颗粒作为药物载体已受到关注。要求载体是惰性的、无毒的，并且在体内不积累或可降解。因此，我们选择聚-L-赖氨酸（PLL）作为纳米颗粒的主链，它是可降解的多肽。由于PLL随着pH和温度的变化而表现出无规、螺旋和β-折叠之间的结构变化，因此我们期望纳米颗粒中药物的刺激敏感释放。PLL可以与聚乙二醇（PEG）反应以提高分散稳定性并延长在血液中的寿命（mPEG-PLL聚合物）。然后，将 mPEG-PLL 聚合物与充当疏水位点的磷脂酸 (PA) 偶联（mPEG-PLL-PA 纳米颗粒）。所得聚合物通过 PA 部分之间的疏水缔合自发聚集成纳米颗粒形状。而 mPEG-PLL 聚合物在高 pH 值和高温下形成 β-折叠结构后组装成纳米颗粒（mPEG-PLL 纳米颗粒）。两种纳米粒子的尺寸均为10-80nm，并具有正向变化。 FITC 标记的纳米颗粒被内化到 A431 细胞中。由于PA具有很强的疏水性，作为抗癌药物的阿霉素(ADR)比mPEG-PLL纳米颗粒更多地掺入到mPEG-PLL-PA纳米颗粒中。然而，药物释放却表现出相反的趋势。在pH4下，mPEG-PLL纳米颗粒的ADR释放速率比mPEG-PLL-PA纳米颗粒的ADR释放速率快。因此，当用负载ADR的mPEG-PLL纳米粒子处理A431细胞时，A431细胞的存活率降低。我们应用mPEG-PLL聚合物的β-折叠缔合来抑制蛋白质聚集。通过提高 pH 值和温度，PLL 往往会通过 β-折叠缔合而聚集。通过添加 mPEG-PLL 聚合物可以抑制这种聚集。这表明mPEG-PLL聚合物能够抑制引起构象疾病的异常蛋白质的聚集。