Electropermeabilization does not correlate with plasma membrane lipid oxidation.

Area of Science:

• Cell biology
• Biophysics
• Membrane science

Background:

• Electroporation induces temporary cell membrane permeabilization, lasting minutes.
• The mechanisms behind this prolonged membrane leakiness are not fully understood.
• Previous research suggests lipid peroxidation as a potential cause.

Purpose of the Study:

• To investigate the link between plasma membrane oxidation and electric pulse-induced permeabilization in live cells.
• To determine if lipid peroxidation is responsible for the lasting membrane permeability after electroporation.

Main Methods:

• Developed a ratiometric fluorescence method using BODIPY-C11 dye and total internal reflection fluorescence (TIRF) microscopy.
• Applied micro- and submicrosecond electric pulses to CHO-K1 cells cultured on indium tin oxide (ITO) coated coverslips.
• Varied electric field polarity and medium conductance to observe effects on permeabilization and oxidation.

Main Results:

• Oxidation was not detected when the electric field was directed towards the ITO (cathode), even at high strengths.
• Oxidation was observed with the opposite polarity, but required higher electric field thresholds than permeabilization.
• Decreased medium conductance enhanced permeabilization but suppressed lipid oxidation.

Conclusions:

• Lipid oxidation can occur in the plasma membrane following electric pulses.
• Lipid oxidation is not the primary cause of the sustained membrane permeabilization observed after electroporation.