Institut Charles Sadron, Université de Strasbourg, CNRS-UPR 22, 23 rue du Loess, 67034 Strasbourg Cedex 02, France.
C-Cina, BioEMLab, Biozentrum, Mattenstrasse 26, CH-4058 Basel, Switzerland.
Soft Matter. 2022 May 4;18(17):3318-3322. doi: 10.1039/d2sm00179a.
Health concerns associated with the advent of nanotechnologies have risen sharply when it was found that particles of nanoscopic dimensions reach the cell lumina. Plasma and organelle lipid membranes, which are exposed to both the incoming and the engulfed nanoparticles, are the primary targets of possible disruptions. However, reported adhesion, invagination and embedment of nanoparticles (NPs) do not compromise the membrane integrity, precluding direct bilayer damage as a mechanism for toxicity. Here it is shown that a lipid membrane can be torn by small enough nanoparticles, thus unveiling mechanisms for how lipid membrane can be compromised by tearing from nanoparticles. Surprisingly, visualization by cryo transmission electron microscopy (cryo-TEM) of liposomes exposed to nanoparticles revealed also that liposomal laceration is prevented by particle abundance. Membrane destruction results thus from a subtle particle-membrane interplay that is here elucidated. This brings into a firmer molecular basis the theorized mechanisms of nanoparticle effects on lipid bilayers and paves the way for a better assessment of nanoparticle toxicity.
当发现纳米级颗粒到达细胞腔时，与纳米技术出现相关的健康问题急剧增加。暴露于进入的和被吞噬的纳米颗粒的血浆和细胞器的脂膜是可能发生破坏的主要靶标。然而，据报道，纳米颗粒（NPs）的黏附、内陷和嵌入并不损害膜的完整性，排除了直接双层损伤作为毒性机制。在这里，我们表明，足够小的纳米颗粒可以撕裂脂质膜，从而揭示了脂质膜如何通过从纳米颗粒撕裂而受损的机制。令人惊讶的是，通过冷冻传输电子显微镜（cryo-TEM）对暴露于纳米颗粒的脂质体进行可视化还表明，颗粒丰度可以防止脂质体的撕裂。因此，膜的破坏是由细微的颗粒-膜相互作用引起的，这在本文中得到了阐明。这将理论上的纳米颗粒对脂质双层的作用机制建立在更坚实的分子基础上，并为更好地评估纳米颗粒毒性铺平了道路。
