Involvement of reactive oxygen species in membrane electropermeabilization

Abstract

Cell membrane electropermeabilization results in the creation of structural defects in the membrane. Cell membrane electropermeabilization is a stress for the cell. For its defense, the cells exposed to pulsed electric fields are the site of reactive oxygen species generation. This is observed on all cell systems where it has been investigated. Reactive oxygen species are partly generated by electrochemical reactions at the level of the electrodes and diffuse to the cell surface. But an endogenous oxidative burst is present at the cell surface. The amplitude of the oxidative burst is controlled by the pulsing parameters (field strength, pulse number, and duration). This is directly correlated to the extent of the permeabilized cap on the cell surface. This is indeed a major site of its emission. Different biochemical reactions follow this oxidative burst depending on the cell system that was pulsed. Lipid peroxidation is one of the major effects. The loss of cell viability is directly associated with the amplitude of the oxidative burst and its control by scavengers. It strongly affects electric pulse-mediated gene transfer by its damaging effect on plasmids. This can be controlled by the addition of scavengers. Under stringent electric conditions, reactive oxygen species appear to be present in the cytoplasm, where they affect the organelles such as mitochondria with apoptotic consequences.