Department of Chemical Engineering, Delft University of Technology, van der Maasweg 9, 2629 HZ Delft, the Netherlands.
Department of Applied Physics, Science for Life Laboratory, KTH Royal Institute of Technology, 171 65 Solna, Sweden; Faculty of Electrical Engineering, University of Ljubljana, Trzaska 25, 1000 Ljubljana, Slovenia.
Biochim Biophys Acta Biomembr. 2021 Jan 1;1863(1):183468. doi: 10.1016/j.bbamem.2020.183468. Epub 2020 Aug 31.
Transient physical disruption of cell membranes by electric pulses (or electroporation) has significance in biomedical and biological applications requiring the delivery of exogenous (bio)molecules to living cells. We demonstrate that actin networks regulate the cell membrane permeability during electroporation. Disruption of actin networks increases the uptake of membrane-impermeable molecules such as propidium iodide during electroporation. Our experiments at different temperatures ranging from 11 °C to 37 °C show that molecular uptake during electroporation increases with temperature. Furthermore, by examining the temperature-dependent kinetics of propidium iodide uptake, we infer that the activation energy barrier of electroporation is lowered when the actin networks are disrupted. Our numerical calculations of transmembrane voltage show that the reduced activation energy barrier for the cells with disrupted actin is not a consequence of the changes in transmembrane voltage associated with changes in the cell shape due to the disruption of actin, indicating that this could be due to changes in membrane mechanical properties. Our results suggest that the current theoretical models of electroporation should be advanced further by including the contributions of the cytoskeletal networks on the cell membrane permeability during the delivery of exogenous materials.
电脉冲（或电穿孔）短暂地破坏细胞膜的物理完整性，在需要将外源（生物）分子递送到活细胞的生物医学和生物学应用中具有重要意义。我们证明，肌动蛋白网络在电穿孔过程中调节细胞膜通透性。破坏肌动蛋白网络会增加电穿孔过程中外源分子（如碘化丙啶）的摄取。我们在 11°C 至 37°C 之间的不同温度下进行的实验表明，电穿孔过程中的分子摄取随温度升高而增加。此外，通过研究碘化丙啶摄取的温度依赖性动力学，我们推断，当肌动蛋白网络被破坏时，电穿孔的活化能势垒降低。我们对跨膜电压的数值计算表明，由于肌动蛋白的破坏导致细胞形状发生变化，与跨膜电压相关的变化会导致跨膜电压发生变化，而破坏肌动蛋白的细胞的降低的活化能势垒并不是这种情况的结果，这表明这可能是由于细胞膜机械性能的变化所致。我们的研究结果表明，在递外源性物质时，当前的电穿孔理论模型应进一步考虑细胞骨架网络对细胞膜通透性的贡献。
