Cross-linked polymeric nanogel formulations of 5'-triphosphates of nucleoside analogues: role of the cellular membrane in drug release.
Cross-linked polymeric nanogel formulations of 5'-triphosphates of nucleoside analogues: role of the cellular membrane in drug release.
复制标题
核苷类似物 5-三磷酸的交联聚合物纳米凝胶制剂：细胞膜在药物释放中的作用。
DOI：
10.1021/mp0500364
复制
发表时间：
2005
影响因子：
4.9
通讯作者：
Zeman,ArinD
中科院分区：
文献类型：
--
作者：
Vinogradov,SergueiV;Kohli,Ekta;Zeman,ArinD
细胞毒性核苷类似物在体内的激活主要依赖于其细胞特异性的磷酸化。使用核苷类似物的抗癌化疗可以通过细胞内给予活性磷酸化药物而显著增强。然而，阴离子化合物的细胞转运是非常无效的，并且受到许多药物外排转运体的限制。最近发展起来的阳离子纳米凝胶载体可以包裹大量的核苷5‘-三磷酸，这些核苷在纳米凝胶的聚乙烯亚胺骨架上与质子化的氨基形成多离子络合物。本文合成了抗病毒核苷类似物3‘-叠氮-2’，3‘-二脱氧胸苷(AZT)的5’-三磷酸，并将其与纳米凝胶形成络合物，评价其作为治疗人乳腺癌细胞的潜在细胞毒药物剂型。用选择性磷酸化试剂三咪唑基磷酸盐一锅法将AZT转化为核苷类似物5‘-三磷酸。3‘-叠氮-2’，3‘-二脱氧胸苷5’-三磷酸(AZTTP)得到高产率(75%)。通过混合载体和药物的溶液，纳米凝胶包裹了高达30%的AZTTP重量。AZTTP/纳米凝胶制剂对两种乳腺癌细胞株MCF-7和MDA-MB-231显示出增强的细胞毒性，IC50值130−比单独使用AZT低200倍。药物从纳米凝胶中释放的确切机制尚不清楚。一种机制可能涉及与带负电荷的反离子相互作用。已经观察到纳米凝胶对分离的细胞膜具有很高的亲和力，特别是对于由两亲性嵌段共聚物Pluronic P85制成的纳米凝胶。以聚乙烯亚胺配位的铜(II)离子为对照，用透射电子显微镜研究了纳米凝胶粒子的细胞输运行为，揭示了纳米凝胶的膜特性。在载药纳米凝胶与细胞膜相互作用后，观察到微囊药物的大量释放。提出了载药纳米凝胶与磷脂双层相互作用的药物释放机制。关键词：纳米凝胶；3‘-叠氮-2’，3‘-二脱氧胸苷5’-三磷酸；合成；细胞毒性；膜；细胞转运；癌症
Activation of cytotoxic nucleoside analogues in vivo depends primarily on their cell-specific phosphorylation. Anticancer chemotherapy using nucleoside analogues may be significantly enhanced by intracellular administration of active phosphorylated drugs. However, the cellular transport of anionic compounds is very ineffective and restricted by many drug efflux transporters. Recently developed cationic nanogel carriers can encapsulate large amounts of nucleoside 5‘-triphosphates that form polyionic complexes with protonated amino groups on the polyethylenimine backbone of the nanogels. In this paper, the 5‘-triphosphate of an antiviral nucleoside analogue, 3‘-azido-2‘,3‘-dideoxythymidine (AZT), was efficiently synthesized and its complexes with nanogels were obtained and evaluated as potential cytotoxic drug formulations for treatment of human breast carcinoma cells. A selective phosphorylating reagent, tris-imidazolylphosphate, was used to convert AZT into the nucleoside analogue 5‘-triphosphate using a one-pot procedure. The corresponding 3‘-azido-2‘,3‘-dideoxythymidine 5‘-triphosphate (AZTTP) was isolated with high yield (75%). Nanogels encapsulated up to 30% of AZTTP by weight by mixing solutions of the carrier and the drug. The AZTTP/nanogel formulation showed enhanced cytotoxicity in two breast cancer cell lines, MCF-7 and MDA-MB-231, demonstrating IC50values 130−200 times lower than those values for AZT alone. The exact mechanism of drug release from nanogels remains unclear. One mechanism could involve interaction with negatively charged counterions. A high affinity of nanogels to isolated cellular membranes has been observed, especially for nanogels made of amphiphilic block copolymer, Pluronic P85. Cellular trafficking of nanogel particles, contrasted by polyethylenimine-coordinated copper(II) ions, was studied by transmission electron microscopy (TEM), which revealed membranotropic properties of nanogels. A substantial release of encapsulated drug was observed following interactions of drug-loaded nanogels with cellular membranes. A drug release mechanism triggered by interaction of the drug-loaded nanogels with phospholipid bilayer is proposed. The results illustrate therapeutic potential of the phosphorylated nucleoside analogues formulated in nanosized cross-linked polymeric carriers for cancer chemotherapy.Keywords: Nanogels; 3‘-azido-2‘,3‘-dideoxythymidine 5‘-triphosphate; synthesis; cytotoxicity; membrane; cellular trafficking; cancer