Abstract：
Acanthamoeba castellanii are opportunistic pathogens known to cause infection of the central nervous system termed: granulomatous amoebic encephalitis, that mostly effects immunocompromised individuals, and a sight threatening keratitis, known as Acanthamoeba keratitis, which mostly affects contact lens wearers. The current treatment available is problematic, and is toxic. Herein, an amphiphilic star polymer with AB2 miktoarms [A = hydrophobic poly(ℇ-Caprolacton) and B = hydrophilic poly (ethylene glycol)] was synthesized by ring opening polymerization and CuI catalyzed azide-alkyne cycloaddition. Characterization by 1H and 13C NMR spectroscopy, size-exclusion chromatography and fluorescence spectroscopy was accomplished. The hydrophobic drug itraconazole (ITZ) was incorporated in self-assembled micellar structure of AB2 miktoarms through co-solvent evaporation. The properties of ITZ loaded (ITZ-PCL-PEG2) and blank micelles (PCL-PEG2) were investigated through zeta sizer, scanning electron microscopy and Fourier-transform infrared spectroscopy. Itraconazole alone (ITZ), polymer (DPB-PCL), empty polymeric micelles (PCL-PEG2) alone, and itraconazole loaded in polymeric micelles (ITZ-PCL-PEG2) were tested for anti-amoebic potential against Acanthamoeba, and the cytotoxicity on human cells were determined. The polymer was able to self-assemble in aqueous conditions and exhibited low value for critical micelle concentration (CMC) 0.05-0.06 µg/mL. The maximum entrapment efficiency of ITZ was 68%. Of note, ITZ, DPB, PCL-PEG2 and ITZ-PCL-PEG2 inhibited amoebae trophozoites by 37.34%, 36.30%, 35.77%, and 68.24%, respectively, as compared to controls. Moreover, ITZ-PCL-PEG2 revealed limited cytotoxicity against human keratinocyte cells. These results are indicative that ITZ-PCL-PEG2 micelle show significantly better anti-amoebic effects as compared to ITZ alone and thus should be investigated further in vivo to determine its clinical potential.
摘要：
castellanii棘阿米巴是已知引起中枢神经系统感染的机会病原体，称为肉芽肿性阿米巴脑炎，主要影响免疫功能低下的个体，和视力威胁的角膜炎，被称为棘阿米巴角膜炎，主要影响隐形眼镜佩戴者。目前可用的治疗方法是有问题的，而且有毒.在这里，通过开环聚合和CuI催化的叠氮-炔环加成反应合成了具有AB2miktobarms[A=疏水性聚（聚-丙内酯）和B=亲水性聚（乙二醇）]的两亲性星形聚合物。通过1H和13CNMR光谱表征，完成了尺寸排阻色谱和荧光光谱。通过共溶剂蒸发将疏水性药物伊曲康唑（ITZ）掺入AB2miktoarms的自组装胶束结构中。通过zetasizer研究了负载ITZ（ITZ-PCL-PEG2）和空白胶束（PCL-PEG2）的性质，扫描电子显微镜和傅里叶变换红外光谱。单独伊曲康唑（ITZ），聚合物(DPB-PCL),单独的空聚合物胶束（PCL-PEG2），和负载在聚合物胶束（ITZ-PCL-PEG2）中的伊曲康唑对棘阿米巴的抗阿米巴潜力进行了测试，并测定了对人类细胞的细胞毒性。聚合物能够在水性条件下自组装，并且对于临界胶束浓度（CMC）0.05-0.06µg/mL表现出较低的值。ITZ的最大包封效率为68%。值得注意的是，ITZ,DPB,PCL-PEG2和ITZ-PCL-PEG2对变形虫滋养体的抑制作用达37.34%,36.30%，35.77%,和68.24%，分别,与对照组相比。此外，ITZ-PCL-PEG2显示针对人角质形成细胞的有限细胞毒性。这些结果表明,与单独的ITZ相比,ITZ-PCL-PEG2胶束显示出显著更好的抗阿米巴效应,因此应进一步体内研究以确定其临床潜力。
