Sonoporation-induced depolarization of plasma membrane potential: analysis of heterogeneous impact.
Disrupting plasma membrane integrity would inevitably promote anomalous ion fluxes across the membrane and thereby upset the trans-membranous potential. In this article, we report new findings on how sonoporation as a physical membrane perforation strategy would lead to different forms of plasma membrane potential disruption. Our investigation was conducted with a customized fluorescence imaging platform that enabled live monitoring of plasma membrane potential in relation to individual sonoporation events triggered on HeLa cervical cancer cells. Sonovue microbubbles were used as sonoporation agents (added at a 4:3 cell-to-bubble ratio), and they were activated by 1-MHz pulsed ultrasound with 0.35-MPa peak negative pressure, 20-cycle pulse duration, 20-Hz pulse repetition frequency and 1-s total exposure duration. Results indicate that the plasma membrane potential response was heterogeneous among sonoporated cells: (i) membrane potential of irreversibly sonoporated cells was permanently depolarized; (ii) reversibly sonoporated cells exhibited either transient or sustained membrane depolarization; (iii) intact cells adjacent to sonoporated ones underwent transitory membrane depolarization. These findings effectively serve to substantiate the causal relationship between sonoporation and plasma membrane potential.
Department of Instrumentation Science and Engineering, Shanghai Jiaotong University, Shanghai, China. Electronic address: pqin@sjtu.edu.cn.
Peng
P
Qin
Shanghai Institute of Biological Sciences, Chinese Academy of Sciences, Shanghai, China.
Lin
L
Xu
Medical Engineering Program, University of Hong Kong, Pokfulam, Hong Kong.
Yaxin
Y
Hu
Medical Engineering Program, University of Hong Kong, Pokfulam, Hong Kong.
Wenjing
W
Zhong
Department of Instrumentation Science and Engineering, Shanghai Jiaotong University, Shanghai, China.
Ping
P
Cai
Department of Ultrasound, Shanghai Jiaotong University Affiliated People's Hospital, Shanghai, China.
Lianfang
L
Du
Department of Ultrasound, Shanghai Jiaotong University Affiliated People's Hospital, Shanghai, China.
Lifang
L
Jin
Medical Engineering Program, University of Hong Kong, Pokfulam, Hong Kong. Electronic address: alfred.yu@hku.hk.
Alfred C H
AC
Yu
D002462:Cell Membrane / Q000502:physiology* / Q000648:ultrastructure; D002463:Cell Membrane Permeability / Q000502:physiology; D005260:Female; D006801:Humans; D008564:Membrane Potentials / Q000502:physiology*; D045423:Microbubbles; D061848:Optical Imaging / Q000379:methods; D010743:Phospholipids; D013010:Sonication / Q000379:methods*; D013459:Sulfur Hexafluoride; D014407:Tumor Cells, Cultured; D014465:Ultrasonics / Q000379:methods*
D010743:Phospholipids; C420843:contrast agent BR1; D013459:Sulfur Hexafluoride
Depolarization; Heterogeneous response; Plasma membrane potential; Sonoporation