Alkyl Chain Length in Poly(2-oxazoline)-Based Amphiphilic Gradient Copolymers Regulates the Delivery of Hydrophobic Molecules: A Case of the Biodistribution and the Photodynamic Activity of the Photosensitizer Hypericin
作者:Veronika Huntošová、Shubhashis Datta、Lenka Lenkavská、Mariana Máčajová、Boris Bilčík、Barbora Kundeková、Ivan Čavarga、Juraj Kronek、Annamária Jutková、Pavol Miškovský、Daniel Jancura
DOI:10.1021/acs.biomac.1c00768
日期:2021.10.11
Self-assembled nanostructures of amphiphilic gradient copoly(2-oxazoline)s have recently attracted attention as promising delivery systems for the effective delivery of hydrophobic anticancer drugs. In this study, we have investigated the effects of increasing hydrophobic side chain length on the self-assembly of gradient copolymers composed of 2-ethyl-2-oxazoline as the hydrophilic comonomer and various 2-(4-alkyloxyphenyl)-2-oxazolines as hydrophobic comonomers. We show that the size of the formed polymeric nanoparticles depends on the structure of the copolymers. Moreover, the stability and properties of the polymeric assembly can be affected by the loading of hypericin, a promising compound for photodiagnostics and photodynamic therapy (PDT). We have found the limitation that allows rapid or late release of hypericin from polymeric nanoparticles. The nanoparticles entering the cells by endocytosis decreased the hypericin-induced PDT, and the contribution of the passive process (diffusion) increased the probability of a stronger photoeffect. A study of fluorescence pharmacokinetics and biodistribution revealed differences in the release of hypericin from nanoparticles toward the quail chorioallantoic membrane, a preclinical model for in vivo studies, depending on the composition of polymeric nanoparticles. Photodamage induced by PDT in vivo well correlated with the in vitro results. All formulations studied succeeded in targeting hypericin at cancer cells. In conclusion, we demonstrated the promising potential of poly(2-oxazoline)-based gradient copolymers for effective drug delivery and sequential drug release needed for successful photodiagnostics and PDT in cancer therapy.
自组装的两亲梯度共聚(2-噁唑啉)纳米结构最近因其作为有效传递疏水性抗癌药物的潜在传递系统而受到关注。在本研究中,我们调查了增加疏水侧链长度对由2-乙基-2-噁唑啉作为亲水共聚单体和各种2-(4-烷基氧基苯基)-2-噁唑啉作为疏水共聚单体构成的梯度共聚物自组装的影响。我们表明,形成的聚合物纳米粒子的大小取决于共聚物的结构。此外,聚合物组装的稳定性和特性会受到负载的超敏素的影响,超敏素是用于光诊断和光动力疗法(PDT)的前景化合物。我们发现了一个限制,使超敏素能够从聚合物纳米粒子中快速或延迟释放。通过内吞作用进入细胞的纳米粒子降低了超敏素诱导的PDT效果,而被动过程(扩散)的贡献则增加了更强光效应的概率。荧光药代动力学和生物分布的研究揭示了超敏素从纳米粒子释放到鹌鹑卵黄膜(一个用于体内研究的临床前模型)中存在差异,这取决于聚合物纳米粒子的成分。体内PDT诱导的光损伤与体外结果良好相关。所有研究的制剂在靶向癌细胞方面均成功实现了超敏素的传递。总之,我们展示了基于聚(2-噁唑啉)的梯度共聚物在有效药物传递和顺序药物释放方面的前景潜力,这些都是成功实施癌症治疗中光诊断和PDT所需的。