Wang Heye, Zhang Xiaohan, Liu Yibo, Liu Juewen
Jiangsu Key Laboratory of Food Quality and Safety-State Key Laboratory Cultivation Base of MOST, Institute of Food Safety and Nutrition, Jiangsu Academy of Agricultural Sciences, Nanjing, Jiangsu 210014, China.
Department of Chemistry, Waterloo Institute for Nanotechnology, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada.
ACS Omega. 2018 Nov 30;3(11):15353-15360. doi: 10.1021/acsomega.8b02448. Epub 2018 Nov 13.
Perfluorinated compounds (PFCs) are emerging persistent environmental contaminants that may be toxic to animals and humans. To gain fundamental insights into the mechanism of their toxicity, the interactions of phosphocholine (PC) liposomes as model membranes were studied with three types of PFCs, including perfluorooctanoic acid, perfluorooctane sulfonate, and perfluorohexanesulfonic acid potassium salt, together with three common surfactants: sodium dodecyl sulfate (SDS), cetyltrimethylammonium bromide (CTAB), and sodium 1-heptanesulfonate (SHS). The interactions were systematically characterized by zeta potential measurement, dynamic light scattering, negative-stain transmission electron microscopy, and fluorescence spectroscopy. Unmodified liposomes, calcein-loaded liposomes, and Laurdan dye-embedded liposomes were all tested. By gradually increasing the temperature, the three PFCs and SHS decreased the leakage of calcein-loaded 1,2-dipalmitoyl--glycero-3-phosphocholine liposomes, whereas SDS and CTAB increased the leakage. The PFCs that affected the lipid membranes stronger than SHS were attributable to their perfluoroalkyl carbon chains. Packing of the lipids was further studied using Laurdan dye as a probe. Calcein leakage tests also indicated that PFCs inhibited lipid membrane leakage induced by inorganic nanoparticles such as silica and gold nanoparticles. This study confirmed the similar effect of the PFCs as cholesterol in affecting membrane properties and would be helpful for understanding the interaction mechanism of PFCs and cell membranes.
全氟化合物（PFCs）是新出现的持久性环境污染物，可能对动物和人类有毒。为了深入了解其毒性机制，研究了作为模型膜的磷酸胆碱（PC）脂质体与三种全氟化合物（包括全氟辛酸、全氟辛烷磺酸和全氟己烷磺酸钾盐）以及三种常见表面活性剂（十二烷基硫酸钠（SDS）、十六烷基三甲基溴化铵（CTAB）和1-庚烷磺酸钠（SHS））之间的相互作用。通过zeta电位测量、动态光散射、负染色透射电子显微镜和荧光光谱对这些相互作用进行了系统表征。对未修饰的脂质体、载有钙黄绿素的脂质体和包埋了劳丹染料的脂质体都进行了测试。通过逐渐升高温度，三种全氟化合物和SHS降低了载有钙黄绿素的1,2-二棕榈酰-sn-甘油-3-磷酸胆碱脂质体的渗漏，而SDS和CTAB则增加了渗漏。比SHS对脂质膜影响更强的全氟化合物归因于它们的全氟烷基碳链。使用劳丹染料作为探针进一步研究了脂质的堆积情况。钙黄绿素渗漏试验还表明，全氟化合物抑制了由二氧化硅和金纳米颗粒等无机纳米颗粒诱导的脂质膜渗漏。本研究证实了全氟化合物在影响膜性质方面与胆固醇具有相似的作用，这将有助于理解全氟化合物与细胞膜的相互作用机制。
