Periodic Reporting for period 1 - EPmIC (Controlling the susceptibility of biological cells to pulsed electric field treatment by using ion channel modulators)
Periodo di rendicontazione: 2021-03-01 al 2023-01-31
The project addressed the issue of understanding the effects of ion channels and ion channel modulators on the response of biological cells to pulsed electric field treatment. This is important, as it contributes to the advancement of knowledge in the field of electroporation, which has implications for various medical applications including cancer treatment, cardiac ablation, and gene delivery. The scientific objectives of the project were to identify ion channels contributing to changes in transmembrane voltage following electroporation of cells in vitro, develop computational models describing the cells’ electrophysiological response to electroporation, and explore the potential use of ion channel modulators to influence cell susceptibility to electroporation. The training objectives were linked to acquiring new transferable skills, new experimental/technical skills, and extending the modeling skills of the researcher.
The experimental results guided the development of computational models describing the effects of electroporation on changes in transmembrane voltage in non-excitable and excitable cells. The models revealed that even a small increase in nonselective ionic current associated with electroporation can lead to complete depolarization of the membrane. We found that under typical electroporation conditions, the nonselective leak current is sufficiently high to render the transmembrane voltage unaffected by ion channel modulators. However, during the membrane resealing phase, activation of ion channels was observed to contribute to changes in transmembrane voltage. Additionally, experiments were conducted to assess the potential use of ion channel modulators in influencing cell susceptibility to electroporation treatment. The original plan was to test ion channel modulators that influence the extent and longevity of membrane depolarization following electroporation; however, we found that optical measurements of transmembrane voltage became unreliable when approaching conditions of irreversible electroporation and cell death. We instead tested the sodium channel inhibitor lidocaine, which is generally used for local anesthesia in electroporation treatments. The results indicate that lidocaine potentiated cell death, but this effect was primarily attributed to the cytotoxicity of lidocaine itself, with minimal synergistic effects with electroporation. In addition to the scientific work, the researcher gained new expertise in experimental and theoretical methodologies, acquired new teaching experience and experience in independent supervision of BSc, MSc, and PhD students, and secured an ERC Starting Grant that will continue and expands the research initiated during the project. Consequently, the project significantly contributed to the researcher’s academic career development as an independent principal investigator.
The project contributed to the state of the art of electroporation research through enhancing the knowledge of molecular mechanisms of electroporation and their effects on the cells electrophysiological response – phenomena that are still very much understudied but are becoming increasingly important with the development of new electroporation-based treatments of excitable tissues. The development of novel computational models at the molecular level of the cell membrane, the cellular level, and the level of cell monolayer, will help explain and predict the changes in transmembrane voltage, including changes in action potential generation and propagation in excitable cells and prolonged membrane depolarization in both excitable and non-excitable cells. This is important for developing digital (simulation) tools that can help improve the efficacy of electroporation treatments, such as ablation of arrhythmogenic cardiac tissue using irreversible electroporation. Overall, the main socio-economic impacts are linked with advances in healthcare technologies. In addition, the project contributed to society through training of undergraduate and graduate students, as well as through promoting science and technology among primary and secondary school pupils and the general public.